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Larsen BD, Skodborg Villadsen J, Skarbaliene J, Melander C, Russell W, Petersen YM, Horn Møller E. Creating Glepaglutide, the First Long-Acting GLP-2 Analogue to Enable a Ready-to-Use Injection. J Med Chem 2025; 68:3134-3145. [PMID: 39851172 DOI: 10.1021/acs.jmedchem.4c02361] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2025]
Abstract
Human glucagon-like peptide-2 (hGLP-2) receptor agonists have a benefit for the treatment of short bowel syndrome (SBS) and potentially other intestinal diseases (e.g., IBD). Native hGLP-2, a 33-amino acid gastrointestinal hormone, has a short half-life and is chemically and physically unstable, rendering it unsuitable for clinical use. In this paper, we describe the design of novel hGLP-2 peptide analogues with significantly improved chemical and physical properties, high in vitro hGLP-2 receptor potencies, and extended half-lives. Furthermore, synthesis yields were significantly improved by the addition of a C-terminal (lysine)6 tail (Structure Inducing Probe technology, SIP). One hGLP-2 analogue described herein is glepaglutide ([Gly2Glu3Thr5Ser8Leu10Ala11,16,24,28] hGLP-2[1-33]-NH-[Lys]6-NH2), the first long-acting analogue with excellent physicochemical stability, making it suitable for liquid formulation. Glepaglutide is currently in phase 3 clinical trials as a potential new therapy for SBS and is the only hGLP-2 analogue in clinical testing that is dosed subcutaneously from a ready-to-use formulation in an autoinjector.
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Affiliation(s)
| | | | | | | | - Wayne Russell
- Aqilion AB, Kullagatan 8, 252 20 Helsingborg, Sweden
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2
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Voudren CD, Mayhue EJ, Riehm MD, Jugan MC. Evaluation of the relationship between plasma glucagon-like peptide-2 and gastrointestinal dysbiosis in canine chronic enteropathies. PLoS One 2024; 19:e0305711. [PMID: 38935795 PMCID: PMC11210855 DOI: 10.1371/journal.pone.0305711] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2024] [Accepted: 06/04/2024] [Indexed: 06/29/2024] Open
Abstract
Chronic enteropathies are a common cause of morbidity in dogs and are associated with disruption of the normal gastrointestinal mucosal barrier. The objective of this prospective study was to determine the association between measures of gastrointestinal dysbiosis and plasma concentrations of glucagon-like peptide-2, a hormone responsible for normal mucosal structure, in dogs with chronic enteropathies. Fecal 16S V4 rRNA gene sequencing and quantitative PCR via the dysbiosis index was performed on 16 healthy controls and 18 dogs with chronic enteropathy prior to and 1 month after initiation of individualized therapy. Fasting and post-prandial plasma GLP-2 concentrations were measured via ELISA in healthy dogs and chronic enteropathy dogs at both time points. Alpha and beta diversity indices, as well as bacterial population abundances were compared between groups and time-points. Principal component analysis combined with least squares regression was used to identify taxa contributing to glucagon-like peptide-2 variance among groups. While the dysbiosis index did not differ between healthy dogs and dogs with chronic enteropathy, 16S V4 genomic sequencing identified 47 operational taxonomic units that differed between the groups, all but 2 of which resolved following chronic enteropathy treatment. Principal component analysis identified 6 families and 19 genera that contributed to differences in glucagon-like peptide-2 concentrations between groups. Dysbiosis associated with chronic enteropathies in dogs may contribute to the observed lower plasma glucagon-like peptide-2 concentrations. Further research into mechanisms of microbiota impact on the enteroendocrine system is needed. Association between glucagon-like peptide-2 secretion and microbiome indices may help to guide research into future treatment strategies for dogs with chronic enteropathy.
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Affiliation(s)
- Caylie D. Voudren
- Department of Clinical Sciences, College of Veterinary Medicine, Kansas State University, Manhattan, KS, United States of America
| | - Erin J. Mayhue
- Department of Clinical Sciences, College of Veterinary Medicine, Kansas State University, Manhattan, KS, United States of America
| | - Michelle D. Riehm
- Department of Clinical Sciences, College of Veterinary Medicine, Kansas State University, Manhattan, KS, United States of America
| | - Maria C. Jugan
- Department of Clinical Sciences, College of Veterinary Medicine, Kansas State University, Manhattan, KS, United States of America
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3
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Hassan HM, Salama MM. Editorial: Implication of oxidative, inflammatory, apoptotic and autophagy pathways in colitis. Front Pharmacol 2023; 14:1326176. [PMID: 38161704 PMCID: PMC10755908 DOI: 10.3389/fphar.2023.1326176] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2023] [Accepted: 12/05/2023] [Indexed: 01/03/2024] Open
Affiliation(s)
- Hanan M. Hassan
- Department of Pharmacology and Biochemistry, Faculty of Pharmacy, Delta University for Science and Technology, Gamasa, Egypt
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4
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Rim DS, Shin JH, Jacoba I, Sharma K, Kim DW. Case report: Exploring teduglutide as a therapeutic option for refractory microscopic colitis: insights and implications. Front Med (Lausanne) 2023; 10:1231565. [PMID: 37649980 PMCID: PMC10462905 DOI: 10.3389/fmed.2023.1231565] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2023] [Accepted: 07/28/2023] [Indexed: 09/01/2023] Open
Abstract
Microscopic colitis is a chronic inflammatory condition of the colon characterized by chronic watery diarrhea, generally with endoscopically normal or nonspecific findings, and can be diagnosed by histopathological examination of colon mucosal biopsies. Some patients experience severe symptoms that do not respond to conventional medical treatment. A glucagon-like peptide-2 (GLP-2) analog, teduglutide, is used in patients with short bowel syndrome (SBS) dependent on parenteral support. In this case report, we describe a patient with microscopic colitis who demonstrated significant symptom improvement following teduglutide treatment.
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Affiliation(s)
- Daniel Sungku Rim
- Department of Medicine, Section of Endocrinology, Diabetes, Nutrition and Weight Management, Boston University Chobanian and Avedisian School of Medicine, Boston, MA, United States
| | - Jeong-Hun Shin
- Department of Medicine, Section of Endocrinology, Diabetes, Nutrition and Weight Management, Boston University Chobanian and Avedisian School of Medicine, Boston, MA, United States
- Department of Internal Medicine, Hanyang University College of Medicine, Seoul, Republic of Korea
| | - Isa Jacoba
- Department of Pathology and Laboratory Medicine, Boston University Chobanian and Avedisian School of Medicine, Boston, MA, United States
| | - Kavita Sharma
- Department of Medicine, Section of Endocrinology, Diabetes, Nutrition and Weight Management, Boston University Chobanian and Avedisian School of Medicine, Boston, MA, United States
| | - Dong Wook Kim
- Department of Medicine, Section of Endocrinology, Diabetes, Nutrition and Weight Management, Boston University Chobanian and Avedisian School of Medicine, Boston, MA, United States
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Skarbaliene J, Mathiesen JM, Larsen BD, Thorkildsen C, Petersen YM. Glepaglutide, a novel glucagon-like peptide-2 agonist, has anti-inflammatory and mucosal regenerative effects in an experimental model of inflammatory bowel disease in rats. BMC Gastroenterol 2023; 23:79. [PMID: 36944922 PMCID: PMC10029296 DOI: 10.1186/s12876-023-02716-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/11/2022] [Accepted: 03/10/2023] [Indexed: 03/23/2023] Open
Abstract
BACKGROUND Glucagon-like peptide-2 (GLP-2) enhances intestinal repair and attenuates inflammation in preclinical inflammatory bowel disease (IBD) models, making GLP-2 analogues attractive candidates for IBD therapy. Glepaglutide is a long-acting GLP-2 receptor agonist in clinical development for treatment of short bowel syndrome. Here, we investigated if glepaglutide is therapeutically beneficial in rats with small intestinal inflammation. METHODS Small intestinal inflammation was induced with indomethacin in naive Wistar rats, followed by glepaglutide administration at different disease stages. Glepaglutide was administered in co-treatment and post-treatment regimens. Small intestinal length and concentrations of inflammatory markers α-1-acid glycoprotein and myeloperoxidase were used to assess anti-inflammatory effects. Small intestinal mass was evaluated to determine intestinotrophic effects. RESULTS Glepaglutide co- and post-treatment significantly reduced severity of small intestinal inflammation, evidenced by reversed small intestinal shortening and decreased α-1-acid glycoprotein and/or myeloperoxidase concentration(s). Co- and post-treatment with glepaglutide also significantly increased small intestinal mass, indicating intestinal regenerative effects. Similar effects were observed in naive rats after glepaglutide treatment. CONCLUSION Glepaglutide has anti-inflammatory and intestinotrophic effects without the need for pre-treatment in a rat model of small intestinal inflammation. Thus, glepaglutide is of potential clinical interest for patients with IBD.
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Affiliation(s)
- Jolanta Skarbaliene
- Research and Development, Zealand Pharma A/S, Sydmarken 11, 2860, Søborg, Denmark
- Pharvaris GmbH, 6300, Grafenauweg 8, Zug, Switzerland
| | | | - Bjarne Due Larsen
- Research and Development, Zealand Pharma A/S, Sydmarken 11, 2860, Søborg, Denmark
| | | | - Yvette Miata Petersen
- Research and Development, Zealand Pharma A/S, Sydmarken 11, 2860, Søborg, Denmark
- Hoffmann-La Roche, Grenzacherstrasse 124, 4070, Basel, Switzerland
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6
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Vambhurkar G, Amulya E, Sikder A, Shah S, Famta P, Khatri DK, Singh SB, Srivastava S. Nanomedicine based potentially transformative strategies for colon targeting of peptides: State-of-the-art. Colloids Surf B Biointerfaces 2022; 219:112816. [PMID: 36108367 DOI: 10.1016/j.colsurfb.2022.112816] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2022] [Revised: 08/23/2022] [Accepted: 08/27/2022] [Indexed: 12/11/2022]
Abstract
Recently, peptides have attracted tremendous attention among researchers attributed to their high target specificity and efficacy compared to conventional therapeutics. The ease of self-administration and non-invasiveness confers oral as the most desirable route. However, numerous challenges associated with peptide delivery through the oral route like harsh gastrointestinal environment, enzymatic degradation, and absorption barriers hinder its clinical translation. Protease activity is more pronounced in the proximal segments of the gastrointestinal tract (GIT). Distal segments like the colon possess lower proteolytic activity, enhanced retention time, etc. which could facilitate easy absorption. However, traversing of the upper segments to reach the colon requires the circumvention of the pitfalls of the GIT. The advent of nanomedicine strategies could help in overcoming the said challenges associated with oral delivery, colon-specific targeting, and improving stability and bioavailability at the active site. Furthermore, the classification of peptides and various nanomedicine strategies for oral delivery of peptides to the colon has been conveyed. Regulatory hurdles and ways to accomplish clinical translation have been addressed.
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Affiliation(s)
- Ganesh Vambhurkar
- Department of Pharmaceutics, National Institute of Pharmaceutical Education and Research (NIPER), Hyderabad, India
| | - Etikala Amulya
- Department of Pharmaceutics, National Institute of Pharmaceutical Education and Research (NIPER), Hyderabad, India
| | - Anupama Sikder
- Department of Pharmaceutics, National Institute of Pharmaceutical Education and Research (NIPER), Hyderabad, India
| | - Saurabh Shah
- Department of Pharmaceutics, National Institute of Pharmaceutical Education and Research (NIPER), Hyderabad, India
| | - Paras Famta
- Department of Pharmaceutics, National Institute of Pharmaceutical Education and Research (NIPER), Hyderabad, India
| | - Dharmendra Kumar Khatri
- Department of Biological Sciences, National Institute of Pharmaceutical Education and Research (NIPER), Hyderabad, India
| | - Shashi Bala Singh
- Department of Biological Sciences, National Institute of Pharmaceutical Education and Research (NIPER), Hyderabad, India
| | - Saurabh Srivastava
- Department of Pharmaceutics, National Institute of Pharmaceutical Education and Research (NIPER), Hyderabad, India.
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7
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Villablanca EJ, Selin K, Hedin CRH. Mechanisms of mucosal healing: treating inflammatory bowel disease without immunosuppression? NATURE REVIEWS. GASTROENTEROLOGY & HEPATOLOGY 2022. [PMID: 35440774] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 12/08/2022]
Abstract
Almost all currently available treatments for inflammatory bowel disease (IBD) act by inhibiting inflammation, often blocking specific inflammatory molecules. However, given the infectious and neoplastic disease burden associated with chronic immunosuppressive therapy, the goal of attaining mucosal healing without immunosuppression is attractive. The absence of treatments that directly promote mucosal healing and regeneration in IBD could be linked to the lack of understanding of the underlying pathways. The range of potential strategies to achieve mucosal healing is diverse. However, the targeting of regenerative mechanisms has not yet been achieved for IBD. Stem cells provide hope as a regenerative treatment and are used in limited clinical situations. Growth factors are available for the treatment of short bowel syndrome but have not yet been applied in IBD. The therapeutic application of organoid culture and stem cell therapy to generate new intestinal tissue could provide a novel mechanism to restore barrier function in IBD. Furthermore, blocking key effectors of barrier dysfunction (such as MLCK or damage-associated molecular pattern molecules) has shown promise in experimental IBD. Here, we review the diversity of molecular targets available to directly promote mucosal healing, experimental models to identify new potential pathways and some of the anticipated potential therapies for IBD.
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Affiliation(s)
- Eduardo J Villablanca
- Division of Immunology and Allergy, Department of Medicine Solna, Karolinska Institutet and University Hospital, Stockholm, Sweden.
| | - Katja Selin
- Gastroenterology unit, Department of Gastroenterology, Dermatovenereology and Rheumatology, Karolinska University Hospital, Stockholm, Sweden.,Department of Medicine Solna, Karolinska Institutet, Stockholm, Sweden
| | - Charlotte R H Hedin
- Gastroenterology unit, Department of Gastroenterology, Dermatovenereology and Rheumatology, Karolinska University Hospital, Stockholm, Sweden. .,Department of Medicine Solna, Karolinska Institutet, Stockholm, Sweden.
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8
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Villablanca EJ, Selin K, Hedin CRH. Mechanisms of mucosal healing: treating inflammatory bowel disease without immunosuppression? Nat Rev Gastroenterol Hepatol 2022; 19:493-507. [PMID: 35440774 DOI: 10.1038/s41575-022-00604-y] [Citation(s) in RCA: 96] [Impact Index Per Article: 32.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 03/08/2022] [Indexed: 12/12/2022]
Abstract
Almost all currently available treatments for inflammatory bowel disease (IBD) act by inhibiting inflammation, often blocking specific inflammatory molecules. However, given the infectious and neoplastic disease burden associated with chronic immunosuppressive therapy, the goal of attaining mucosal healing without immunosuppression is attractive. The absence of treatments that directly promote mucosal healing and regeneration in IBD could be linked to the lack of understanding of the underlying pathways. The range of potential strategies to achieve mucosal healing is diverse. However, the targeting of regenerative mechanisms has not yet been achieved for IBD. Stem cells provide hope as a regenerative treatment and are used in limited clinical situations. Growth factors are available for the treatment of short bowel syndrome but have not yet been applied in IBD. The therapeutic application of organoid culture and stem cell therapy to generate new intestinal tissue could provide a novel mechanism to restore barrier function in IBD. Furthermore, blocking key effectors of barrier dysfunction (such as MLCK or damage-associated molecular pattern molecules) has shown promise in experimental IBD. Here, we review the diversity of molecular targets available to directly promote mucosal healing, experimental models to identify new potential pathways and some of the anticipated potential therapies for IBD.
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Affiliation(s)
- Eduardo J Villablanca
- Division of Immunology and Allergy, Department of Medicine Solna, Karolinska Institutet and University Hospital, Stockholm, Sweden.
| | - Katja Selin
- Gastroenterology unit, Department of Gastroenterology, Dermatovenereology and Rheumatology, Karolinska University Hospital, Stockholm, Sweden.,Department of Medicine Solna, Karolinska Institutet, Stockholm, Sweden
| | - Charlotte R H Hedin
- Gastroenterology unit, Department of Gastroenterology, Dermatovenereology and Rheumatology, Karolinska University Hospital, Stockholm, Sweden. .,Department of Medicine Solna, Karolinska Institutet, Stockholm, Sweden.
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9
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Xie X, Geng C, Li X, Liao J, Li Y, Guo Y, Wang C. Roles of gastrointestinal polypeptides in intestinal barrier regulation. Peptides 2022; 151:170753. [PMID: 35114316 DOI: 10.1016/j.peptides.2022.170753] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/17/2021] [Revised: 01/29/2022] [Accepted: 01/30/2022] [Indexed: 12/17/2022]
Abstract
The intestinal barrier is a dynamic entity that is organized as a multilayer system and includes various intracellular and extracellular elements. The gut barrier functions in a coordinated manner to impede the passage of antigens, toxins, and microbiome components and simultaneously preserves the balanced development of the epithelial barrier and the immune system and the acquisition of tolerance to dietary antigens and intestinal pathogens.Numerous scientific studies have shown a significant association between gut barrier damage and gastrointestinal and extraintestinal diseases such as inflammatory bowel disease, celiac disease and hepatic fibrosis. Various internal and external factors regulate the intestinal barrier. Gastrointestinal peptides originate from enteroendocrine cells in the luminal digestive tract and are critical gut barrier regulators. Recent studies have demonstrated that gastrointestinal peptides have a therapeutic effect on digestive tract diseases, enhancing epithelial barrier activity and restoring the gut barrier. This review demonstrates the roles and mechanisms of gastrointestinal polypeptides, especially somatostatin (SST) and vasoactive intestinal peptide (VIP), in intestinal barrier regulation.
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Affiliation(s)
- Xiaoxi Xie
- Department of Gastroenterology, West China Hospital of Sichuan University, Chengdu, China
| | - Chong Geng
- Department of Gastroenterology, West China Hospital of Sichuan University, Chengdu, China
| | - Xiao Li
- Department of Gastroenterology, West China Hospital of Sichuan University, Chengdu, China; Division of Digestive Diseases, West China Hospital of Sichuan University, Chengdu, China
| | - Juan Liao
- Non-communicable Diseases Research Center, West China-PUMC C.C. Chen Institute of Health, Sichuan University, Chengdu, China
| | - Yanni Li
- Department of Gastroenterology, West China Hospital of Sichuan University, Chengdu, China
| | - Yaoyu Guo
- Department of Gastroenterology, West China Hospital of Sichuan University, Chengdu, China
| | - Chunhui Wang
- Department of Gastroenterology, West China Hospital of Sichuan University, Chengdu, China.
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10
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Lucotti P, Lovati E, Lenti MV, Valvo B, Sprio E, Aronico N, Giuffrida P, Dell'Aera D, Pasini A, Ubezio C, Delliponti M, Tinelli C, Corazza GR, Di Sabatino A. Abnormal post-prandial glucagon-like peptide release in patients with Crohn's disease. Clin Res Hepatol Gastroenterol 2021; 45:101533. [PMID: 33036955 DOI: 10.1016/j.clinre.2020.08.011] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/19/2020] [Revised: 07/31/2020] [Accepted: 08/26/2020] [Indexed: 02/04/2023]
Abstract
BACKGROUND AND AIMS Glucagon-like peptide GLP-1 and -2 have been shown to regulate immune responses in immune-mediated disorders, including Crohn's disease (CD). Our aim was to investigate post-prandial GLP release and its potential link to chronic inflammation, insulin secretion/sensitivity and body composition changes in CD patients. METHODS Fifteen patients with CD, 15 healthy controls (HC) and 15 patients with metabolic syndrome (MS) were recruited. All patients underwent assessment of body composition by means of bio-impedance followed by a meal tolerance test (MTT). Only one CD patient did not tolerate the MTT and was excluded. RESULTS Basal GLP-1 levels were up-regulated in CD, however, as compared to HC, stimulated GLP-1 secretion was significantly reduced in CD (-31 %, p < 0.05) as in MS (-52 %, p < 0.003). Similarly, basal GLP-2 levels were comparable to that of HC, while response to MTT in CD was virtually absent (p < 0.05). Similar fasting insulin sensitivity, estimated 1st and 2nd phase insulin secretion and insulinogenic index were found in CD and in HC. Post-prandial GLP secretion was positively correlated to insulin secretion indices, both in CD and MS. In CD, high-sensitive C reactive protein levels (hsCRP) and extra-cellular to intra-cellular water ratio (ECW/ICW), an index of cellular inflammation, were inversely correlated with stimulated GLP-1 (p < 0.05 and p < 0.01, respectively) levels. CONCLUSION CD is characterized by abnormal fasting and post-prandial GLP levels. Circulating GLP influences subclinical inflammation and glucose metabolism in CD patients, but not their body composition parameters.
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Affiliation(s)
- Pietro Lucotti
- First Department of Internal Medicine, San Matteo Hospital Foundation, University of Pavia, Pavia, Italy
| | - Elisabetta Lovati
- First Department of Internal Medicine, San Matteo Hospital Foundation, University of Pavia, Pavia, Italy
| | - Marco Vincenzo Lenti
- First Department of Internal Medicine, San Matteo Hospital Foundation, University of Pavia, Pavia, Italy
| | - Beatrice Valvo
- First Department of Internal Medicine, San Matteo Hospital Foundation, University of Pavia, Pavia, Italy
| | - Elisa Sprio
- First Department of Internal Medicine, San Matteo Hospital Foundation, University of Pavia, Pavia, Italy
| | - Nicola Aronico
- First Department of Internal Medicine, San Matteo Hospital Foundation, University of Pavia, Pavia, Italy
| | - Paolo Giuffrida
- First Department of Internal Medicine, San Matteo Hospital Foundation, University of Pavia, Pavia, Italy
| | - Dominica Dell'Aera
- First Department of Internal Medicine, San Matteo Hospital Foundation, University of Pavia, Pavia, Italy
| | - Alessandra Pasini
- First Department of Internal Medicine, San Matteo Hospital Foundation, University of Pavia, Pavia, Italy
| | - Cristina Ubezio
- First Department of Internal Medicine, San Matteo Hospital Foundation, University of Pavia, Pavia, Italy
| | - Mariangela Delliponti
- First Department of Internal Medicine, San Matteo Hospital Foundation, University of Pavia, Pavia, Italy
| | - Carmine Tinelli
- Clinical Epidemiology and Biometric Unit, San Matteo Hospital Foundation, Pavia, Italy
| | - Gino Roberto Corazza
- First Department of Internal Medicine, San Matteo Hospital Foundation, University of Pavia, Pavia, Italy
| | - Antonio Di Sabatino
- First Department of Internal Medicine, San Matteo Hospital Foundation, University of Pavia, Pavia, Italy.
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11
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Melo FJ, Pinto-Lopes P, Estevinho MM, Magro F. The Role of Dipeptidyl Peptidase 4 as a Therapeutic Target and Serum Biomarker in Inflammatory Bowel Disease: A Systematic Review. Inflamm Bowel Dis 2021; 27:1153-1165. [PMID: 33295607 DOI: 10.1093/ibd/izaa324] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/10/2020] [Indexed: 12/12/2022]
Abstract
BACKGROUND The roles dipeptidyl peptidase 4 (DPP4), aminopeptidase N (APN), and their substrates in autoimmune diseases are being increasingly recognized. However, their significance in inflammatory bowel diseases (IBD) is not entirely understood. This systematic review aims to discuss the pathophysiological processes related to these ectopeptidases while comparing findings from preclinical and clinical settings. METHODS This review was conducted according to the PRISMA guidelines. We performed a literature search in PubMed, SCOPUS, and Web of Science to identify all reports from inception until February 2020. The search included validated animal models of intestinal inflammation and studies in IBD patients. Quality assessment was performed using SYRCLE's risk of bias tool and CASP qualitative and cohort checklists. RESULTS From the 45 included studies, 36 were performed in animal models and 12 in humans (3 reports included both). Overall, the methodological quality of preclinical studies was acceptable. In animal models, DPP4 and APN inhibition significantly improved intestinal inflammation.Glucagon-like peptide (GLP)-1 and GLP-2 analogs and GLP-2-relase-inducing drugs also showed significant benefits in recovery from inflammatory damage. A nonsignificant trend toward disease remission with the GLP-2 analog teduglutide was observed in the sole interventional human study. All human studies reported an inverse correlation between soluble DPP4/CD26 levels and disease severity, in accordance with the proposal of DPP4 as a biomarker for IBD. CONCLUSIONS The use of DPP4 inhibitors and analogs of its substrates has clear benefits in the treatment of experimentally induced intestinal inflammation. Further research is warranted to validate their potential diagnostic and therapeutic applications in IBD patients.
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Affiliation(s)
- Francisco Jorge Melo
- Department of Biomedicine, Unity of Pharmacology and Therapeutics, Faculty of Medicine of the University of Porto, Porto, Portugal
| | - Pedro Pinto-Lopes
- Department of Biomedicine, Unity of Pharmacology and Therapeutics, Faculty of Medicine of the University of Porto, Porto, Portugal.,Department of Internal Medicine, Tâmega e Sousa Hospital Center, Padre Américo Hospital, Penafiel, Portugal
| | - Maria Manuela Estevinho
- Department of Biomedicine, Unity of Pharmacology and Therapeutics, Faculty of Medicine of the University of Porto, Porto, Portugal.,Department of Gastroenterology, Vila Nova de Gaia/Espinho Hospital Center, Vila Nova de Gaia, Portugal
| | - Fernando Magro
- Department of Biomedicine, Unity of Pharmacology and Therapeutics, Faculty of Medicine of the University of Porto, Porto, Portugal.,Unit of Clinical Pharmacology, São João Hospital Center, Porto, Portugal
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12
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Acute Low-Intensity Treadmill Running Upregulates the Expression of Intestinal Glucose Transporters via GLP-2 in Mice. Nutrients 2021; 13:nu13051735. [PMID: 34065342 PMCID: PMC8160680 DOI: 10.3390/nu13051735] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2021] [Revised: 05/11/2021] [Accepted: 05/18/2021] [Indexed: 01/08/2023] Open
Abstract
The effects of exercise on nutrient digestion and absorption in the intestinal tract are not well understood. A few studies have reported that exercise training increases the expression of molecules involved in carbohydrate digestion and absorption. Exercise was also shown to increase the blood concentration of glucagon-like peptide-2 (GLP-2), which regulates carbohydrate digestion and absorption in the small intestine. Therefore, we investigated the effects of exercise on the expression of molecules involved in intestinal digestion and absorption, including GLP-2. Six-week-old male mice were divided into a sedentary (SED) and low-intensity exercise (LEx) group. LEx mice were required to run on a treadmill (12.5 m/min, 1 h), whereas SED mice rested. All mice were euthanized 1 h after exercise or rest, and plasma, jejunum, ileum, and colon samples were collected, followed by analysis via IHC, EIA, and immunoblotting. The levels of plasma GLP-2 and the jejunum expression of the GLP-2 receptor, sucrase-isomaltase (SI), and glucose transporter 2 (GLUT2) were higher in LEx mice. Thus, we showed that acute low-intensity exercise affects the expression of molecules involved in intestinal carbohydrate digestion and absorption via GLP-2. Our results suggest that exercise might be beneficial for small intestine function in individuals with intestinal frailty.
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13
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Chang Y, Deng Q, Zhang Z, Zhao H, Tang J, Chen X, Liu G, Tian G, Cai J, Jia G. Glucagon-like peptide 2 attenuates intestinal mucosal barrier injury through the MLCK/pMLC signaling pathway in a piglet model. J Cell Physiol 2020; 236:3015-3032. [PMID: 32960454 DOI: 10.1002/jcp.30068] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2020] [Revised: 09/03/2020] [Accepted: 09/08/2020] [Indexed: 12/17/2022]
Abstract
Glucagon-like peptide-2 (GLP-2), an intestinotrophic hormone, has drawn considerable attention worldwide due to its potential to promote intestinal development. We investigated the effects and mechanisms of GLP-2 against lipopolysaccharide (LPS)-induced intestinal inflammation and injury both in vitro and in vivo. Forty healthy piglets weaned at the age of 28 days with similar body weight (BW) were assigned to four in vivo treatments with ten piglets each: (i) nonchallenged control; (ii) LPS-challenged control; (iii) LPS + low dose GLP-2; and (iv) LPS + high dose GLP-2. Piglets were subcutaneously injected with phosphate-buffered saline supplemented with GLP-2 at doses of 0, 0, 2, and 10 nmol/kg BW per day for seven consecutive days. The piglets were challenged with an intraperitoneal injection with 100 μg/kg LPS on day 14 to induce intestinal damage. After that, the gene and protein expression levels of representative tight junction proteins and myosin light-chain kinase (MLCK)/phosphorylated myosin light chain (pMLC), as well as proinflammatory cytokine levels were determined using quantitative reverse transcription polymerase chain reaction, western blot, and enzyme-linked immunosorbent assay methods. A high dose of GLP-2 pretreatment increased intestinal permeability by downregulating and redistributing tight junction proteins (p < .05), for example, zona occluden-1 (ZO-1) and occludin. GLP-2 decreased the transcription of proinflammatory cytokines genes including interleukin-1β (IL-1β), IL-6, IL-8, and tumor necrosis factor-α in small intestines (p < .05). GLP-2 prevented the LPS-induced increase in the expression of MLCK dose-dependently and the increase in pMLC levels in the duodenum, jejunum, and ileum. To assess further the protective effect of GLP-2 on LPS-induced intestinal barrier injury after weaning and its possible mechanism, an in vitro intestinal epithelial barrier model was established with IPEC-J2 monolayers and treated with 100 μg/ml LPS with or without 1 × 10-8 mol/L GLP-2 pretreatment. The in vitro analysis included control, LPS, and GLP-2 + LPS treatments. GLP-2 treatment alleviated the destructive effect of LPS on barrier permeability by restoring the expression and ultrastructure of ZO-1 and occludin (p < .05). In addition, GLP-2 reversed the LPS-induced MLCK hyperexpression and pMLC hyperphosphorylation (p < .05). Taken together, our findings revealed a mechanism by which GLP-2 alleviated LPS-challenged intestinal barrier injury and inflammation in weaned piglets and IPEC-J2 cells via the MLCK/pMLC signaling pathway.
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Affiliation(s)
- Yaqi Chang
- Institute of Animal Nutrition, Sichuan Agricultural University, Chengdu, Sichuan, China.,Key Laboratory of Animal Disease-resistant Nutrition, Chengdu, China
| | - Qiuhong Deng
- Institute of Animal Nutrition, Sichuan Agricultural University, Chengdu, Sichuan, China.,Key Laboratory of Animal Disease-resistant Nutrition, Chengdu, China
| | - Zhenyu Zhang
- Institute of Animal Nutrition, Sichuan Agricultural University, Chengdu, Sichuan, China.,Key Laboratory of Animal Disease-resistant Nutrition, Chengdu, China.,Meishan Vocational Technical College, Meishan, China
| | - Hua Zhao
- Institute of Animal Nutrition, Sichuan Agricultural University, Chengdu, Sichuan, China.,Key Laboratory of Animal Disease-resistant Nutrition, Chengdu, China
| | - Jiayong Tang
- Institute of Animal Nutrition, Sichuan Agricultural University, Chengdu, Sichuan, China.,Key Laboratory of Animal Disease-resistant Nutrition, Chengdu, China
| | - Xiaoling Chen
- Institute of Animal Nutrition, Sichuan Agricultural University, Chengdu, Sichuan, China.,Key Laboratory of Animal Disease-resistant Nutrition, Chengdu, China
| | - Guangmang Liu
- Institute of Animal Nutrition, Sichuan Agricultural University, Chengdu, Sichuan, China.,Key Laboratory of Animal Disease-resistant Nutrition, Chengdu, China
| | - Gang Tian
- Institute of Animal Nutrition, Sichuan Agricultural University, Chengdu, Sichuan, China.,Key Laboratory of Animal Disease-resistant Nutrition, Chengdu, China
| | - Jingyi Cai
- Institute of Animal Nutrition, Sichuan Agricultural University, Chengdu, Sichuan, China.,Key Laboratory of Animal Disease-resistant Nutrition, Chengdu, China
| | - Gang Jia
- Institute of Animal Nutrition, Sichuan Agricultural University, Chengdu, Sichuan, China.,Key Laboratory of Animal Disease-resistant Nutrition, Chengdu, China
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Hargrove DM, Alagarsamy S, Croston G, Laporte R, Qi S, Srinivasan K, Sueiras-Diaz J, Wiśniewski K, Hartwig J, Lu M, Posch AP, Wiśniewska H, Schteingart CD, Rivière PJM, Dimitriadou V. Pharmacological Characterization of Apraglutide, a Novel Long-Acting Peptidic Glucagon-Like Peptide-2 Agonist, for the Treatment of Short Bowel Syndrome. J Pharmacol Exp Ther 2020; 373:193-203. [PMID: 32075870 DOI: 10.1124/jpet.119.262238] [Citation(s) in RCA: 40] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2019] [Accepted: 02/18/2020] [Indexed: 12/15/2022] Open
Abstract
Glucagon-like peptide-2 (GLP-2) agonists have therapeutic potential in clinical indications in which the integrity or absorptive function of the intestinal mucosa is compromised, such as in short bowel syndrome (SBS). Native hGLP-2, a 33-amino acid peptide secreted from the small intestine, contributes to nutritional absorption but has a very short half-life because of enzymatic cleavage and renal clearance and thus is of limited therapeutic value. The GLP-2 analog teduglutide (Revestive/Gattex; Shire Inc.) has been approved for use in SBS since 2012 but has a once-daily injection regimen. Pharmacokinetic (PK) and pharmacodynamic studies confirm that apraglutide, a novel GLP-2 analog, has very low clearance, long elimination half-life, and high plasma protein binding compared with GLP-2 analogs teduglutide and glepaglutide. Apraglutide and teduglutide retain potency and selectivity at the GLP-2 receptor comparable to native hGLP-2, whereas glepaglutide was less potent and less selective. In rat intravenous PK studies, hGLP-2, teduglutide, glepaglutide, and apraglutide had clearances of 25, 9.9, 2.8, and 0.27 ml/kg per minute, respectively, and elimination half-lives of 6.4, 19, 16, and 159 minutes, respectively. The unique PK profile of apraglutide administered via intravenous and subcutaneous routes was confirmed in monkey and minipig and translated into significantly greater in vivo pharmacodynamic activity, measured as small intestinal growth in rats. Apraglutide showed greater intestinotrophic activity than the other peptides when administered at less-frequent dosing intervals because of its prolonged half-life. We postulate that apraglutide offers several advantages over existing GLP-2 analogs and is an excellent candidate for the treatment of gastrointestinal diseases, such as SBS. SIGNIFICANCE STATEMENT: Apraglutide is a potent and selective GLP-2 agonist with an extremely low clearance and prolonged elimination half-life, which differentiates it from teduglutide (the only approved GLP-2 agonist). The enhanced pharmacokinetics of apraglutide will benefit patients by enabling a reduced dosing frequency and removing the need for daily injections.
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Affiliation(s)
- Diane M Hargrove
- Ferring Research Institute, Inc., Ferring Pharmaceuticals, San Diego, California (D.M.H., S.A., G.C., R.L., S.Q., K.S., J.S.-D., K.W., J.H., M.L., A.P.P., H.W., C.D.S., P.J.-M.R.) and VectivBio AG, Basel, Switzerland (V.D.)
| | - Sudarkodi Alagarsamy
- Ferring Research Institute, Inc., Ferring Pharmaceuticals, San Diego, California (D.M.H., S.A., G.C., R.L., S.Q., K.S., J.S.-D., K.W., J.H., M.L., A.P.P., H.W., C.D.S., P.J.-M.R.) and VectivBio AG, Basel, Switzerland (V.D.)
| | - Glenn Croston
- Ferring Research Institute, Inc., Ferring Pharmaceuticals, San Diego, California (D.M.H., S.A., G.C., R.L., S.Q., K.S., J.S.-D., K.W., J.H., M.L., A.P.P., H.W., C.D.S., P.J.-M.R.) and VectivBio AG, Basel, Switzerland (V.D.)
| | - Régent Laporte
- Ferring Research Institute, Inc., Ferring Pharmaceuticals, San Diego, California (D.M.H., S.A., G.C., R.L., S.Q., K.S., J.S.-D., K.W., J.H., M.L., A.P.P., H.W., C.D.S., P.J.-M.R.) and VectivBio AG, Basel, Switzerland (V.D.)
| | - Steve Qi
- Ferring Research Institute, Inc., Ferring Pharmaceuticals, San Diego, California (D.M.H., S.A., G.C., R.L., S.Q., K.S., J.S.-D., K.W., J.H., M.L., A.P.P., H.W., C.D.S., P.J.-M.R.) and VectivBio AG, Basel, Switzerland (V.D.)
| | - Karthik Srinivasan
- Ferring Research Institute, Inc., Ferring Pharmaceuticals, San Diego, California (D.M.H., S.A., G.C., R.L., S.Q., K.S., J.S.-D., K.W., J.H., M.L., A.P.P., H.W., C.D.S., P.J.-M.R.) and VectivBio AG, Basel, Switzerland (V.D.)
| | - Javier Sueiras-Diaz
- Ferring Research Institute, Inc., Ferring Pharmaceuticals, San Diego, California (D.M.H., S.A., G.C., R.L., S.Q., K.S., J.S.-D., K.W., J.H., M.L., A.P.P., H.W., C.D.S., P.J.-M.R.) and VectivBio AG, Basel, Switzerland (V.D.)
| | - Kazimierz Wiśniewski
- Ferring Research Institute, Inc., Ferring Pharmaceuticals, San Diego, California (D.M.H., S.A., G.C., R.L., S.Q., K.S., J.S.-D., K.W., J.H., M.L., A.P.P., H.W., C.D.S., P.J.-M.R.) and VectivBio AG, Basel, Switzerland (V.D.)
| | - Jennifer Hartwig
- Ferring Research Institute, Inc., Ferring Pharmaceuticals, San Diego, California (D.M.H., S.A., G.C., R.L., S.Q., K.S., J.S.-D., K.W., J.H., M.L., A.P.P., H.W., C.D.S., P.J.-M.R.) and VectivBio AG, Basel, Switzerland (V.D.)
| | - Mark Lu
- Ferring Research Institute, Inc., Ferring Pharmaceuticals, San Diego, California (D.M.H., S.A., G.C., R.L., S.Q., K.S., J.S.-D., K.W., J.H., M.L., A.P.P., H.W., C.D.S., P.J.-M.R.) and VectivBio AG, Basel, Switzerland (V.D.)
| | - Alexander P Posch
- Ferring Research Institute, Inc., Ferring Pharmaceuticals, San Diego, California (D.M.H., S.A., G.C., R.L., S.Q., K.S., J.S.-D., K.W., J.H., M.L., A.P.P., H.W., C.D.S., P.J.-M.R.) and VectivBio AG, Basel, Switzerland (V.D.)
| | - Halina Wiśniewska
- Ferring Research Institute, Inc., Ferring Pharmaceuticals, San Diego, California (D.M.H., S.A., G.C., R.L., S.Q., K.S., J.S.-D., K.W., J.H., M.L., A.P.P., H.W., C.D.S., P.J.-M.R.) and VectivBio AG, Basel, Switzerland (V.D.)
| | - Claudio D Schteingart
- Ferring Research Institute, Inc., Ferring Pharmaceuticals, San Diego, California (D.M.H., S.A., G.C., R.L., S.Q., K.S., J.S.-D., K.W., J.H., M.L., A.P.P., H.W., C.D.S., P.J.-M.R.) and VectivBio AG, Basel, Switzerland (V.D.)
| | - Pierre J-M Rivière
- Ferring Research Institute, Inc., Ferring Pharmaceuticals, San Diego, California (D.M.H., S.A., G.C., R.L., S.Q., K.S., J.S.-D., K.W., J.H., M.L., A.P.P., H.W., C.D.S., P.J.-M.R.) and VectivBio AG, Basel, Switzerland (V.D.)
| | - Violetta Dimitriadou
- Ferring Research Institute, Inc., Ferring Pharmaceuticals, San Diego, California (D.M.H., S.A., G.C., R.L., S.Q., K.S., J.S.-D., K.W., J.H., M.L., A.P.P., H.W., C.D.S., P.J.-M.R.) and VectivBio AG, Basel, Switzerland (V.D.)
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15
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Fukumori R, Oba M, Izumi K, Otsuka M, Suzuki K, Gondaira S, Higuchi H, Oikawa S. Effects of butyrate supplementation on blood glucagon-like peptide-2 concentration and gastrointestinal functions of lactating dairy cows fed diets differing in starch content. J Dairy Sci 2020; 103:3656-3667. [PMID: 32089297 DOI: 10.3168/jds.2019-17677] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2019] [Accepted: 12/18/2019] [Indexed: 01/09/2023]
Abstract
The objective of this study was to evaluate effects of butyrate supplementation on plasma concentration of glucagon-like peptide-2 (GLP-2), apparent total-tract digestibility, and responses to a grain challenge of lactating dairy cows fed diets differing in starch content. Eight Holstein cows averaging 58.6 ± 9.96 d in milk (4 primiparous cows fitted with rumen cannula and 4 multiparous intact cows) were blocked by parity and assigned to one of two 4 × 4 Latin squares balanced for carryover effects with a 2 × 2 factorial arrangement of treatments. Treatments were dietary starch content [20.6 vs. 27.5%, respectively, for low starch (LS) and high starch (HS)] and butyrate supplementation (butyrate vs. control) with 21-d periods. Butyrate was provided as Gustor BP70 WS (Norel, S.A., Madrid, Spain), containing 70% sodium butyrate and 30% fatty acid mixture, at 2% of dietary dry matter (providing butyrate at 1.1% of dietary dry matter), and control premix contained 70% wheat bran and 30% fatty acid mixture. Feeds, orts, and fecal samples were collected from d 17 to 19 to determine apparent total-tract nutrient digestibility. Blood and rumen fluid samples were collected on d 19. The baseline of dry matter intake (DMI) was determined as average DMI from d 17 to 19 for each cow, and cows were feed-restricted at 60% of the baseline DMI on d 20, and a grain challenge was conducted by providing steam-flaked corn grain at 0.6% of body weight, on an as-fed basis, in addition to each treatment diet on d 21, and blood and ruminal fluid samples were collected. The interaction of dietary starch content by butyrate supplementation was significant for plasma GLP-2 concentration, being greater for cows fed butyrate with the HS diet than those fed the other 3 diets. Cows fed butyrate increased n-butyrate concentration in the ruminal fluid and tended to increase dry matter and organic matter digestibility compared with the control. During the grain challenge, rumen endotoxin concentration increased over time and was higher for cows fed the HS diets compared with those fed LS diets. However, response variables related to inflammation were not affected by the grain challenge. However, serum haptoglobin, lipopolysaccharide-binding protein, and serum amyloid-A concentrations were greater for cows fed butyrate with the LS diet, but not for those fed the HS diet. These results indicate that butyrate supplementation may increase plasma GLP-2 concentration for cows fed HS diets, and total-tract digestibility regardless of dietary starch content. However, butyrate supplementation did not mitigate inflammation in this study.
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Affiliation(s)
- R Fukumori
- Department of Veterinary Medicine, School of Veterinary Medicine, Rakuno Gakuen University, Ebetsu, Japan 069-8501
| | - M Oba
- Department of Agricultural, Food and Nutritional Science, University of Alberta, Edmonton, AB, Canada T6G 2P5.
| | - K Izumi
- Department of Sustainable Agriculture, College of Agriculture, Food and Environment Sciences, Rakuno Gakuen University, Ebetsu, Japan 069-8501
| | - M Otsuka
- Department of Veterinary Medicine, School of Veterinary Medicine, Rakuno Gakuen University, Ebetsu, Japan 069-8501
| | - K Suzuki
- Department of Veterinary Medicine, School of Veterinary Medicine, Rakuno Gakuen University, Ebetsu, Japan 069-8501
| | - S Gondaira
- Department of Veterinary Medicine, School of Veterinary Medicine, Rakuno Gakuen University, Ebetsu, Japan 069-8501
| | - H Higuchi
- Department of Veterinary Medicine, School of Veterinary Medicine, Rakuno Gakuen University, Ebetsu, Japan 069-8501
| | - S Oikawa
- Department of Veterinary Medicine, School of Veterinary Medicine, Rakuno Gakuen University, Ebetsu, Japan 069-8501
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16
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Role of glucagon-like peptides in inflammatory bowel diseases-current knowledge and future perspectives. Naunyn Schmiedebergs Arch Pharmacol 2019; 392:1321-1330. [PMID: 31359088 DOI: 10.1007/s00210-019-01698-z] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2019] [Accepted: 07/15/2019] [Indexed: 12/14/2022]
Abstract
Inflammatory bowel diseases (IBD), including Crohn's disease (CD) and ulcerative colitis (UC), are chronic, relapsing, intestinal inflammatory disorders with complex and yet unrevealed pathogenesis in which genetic, immunological, and environmental factors play a role. Nowadays, a higher proportion of elderly IBD patients with coexisting conditions, such as cardiovascular disease and/or diabetes is recorded, who require more complex treatment and became a great challenge for gastroenterologists. Furthermore, some patients do not respond to anti-IBD therapy. These facts, together with increasing comorbidities in patients with IBD, imply that urgent, more complex, novel therapeutic strategies in the treatment are needed. Glucagon-like peptides (GLPs) possess numerous functions in the human body such as lowering blood glucose level, controlling body weight, inhibiting gastric emptying, reducing food ingestion, increasing crypt cell proliferation, and improving intestinal growth and nutrient absorption. Thus, GLPs and dipeptidyl peptidase IV (DPP-IV) inhibitors have recently gained attention in IBD research. Several animal models showed that treatment with GLPs may lead to improvement of colitis. This review presents data on the multitude effects of GLPs in the inflammatory intestinal diseases and summarizes the current knowledge on GLPs, which have the potential to become a novel therapeutic option in IBD therapy.
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17
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Shelby RD, Cromeens B, Rager TM, Besner GE. Influence of Growth Factors on the Development of Necrotizing Enterocolitis. Clin Perinatol 2019; 46:51-64. [PMID: 30771819 PMCID: PMC6380490 DOI: 10.1016/j.clp.2018.10.005] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Growth factors have important roles in gastrointestinal tract development, maintenance, and response to injury. Various experiments have been used to demonstrate growth factor influence in multiple disease processes. These studies demonstrated enhancement of mucosal proliferation, intestinal motility, immune modulation, and many other beneficial effects. Select growth factors, including epidermal growth factor and heparin-binding epidermal growth factor like growth factor, demonstrate some beneficial effects in experimental and clinical intestinal injury demonstrated in necrotizing enterocolitis. The roles of glucagon-like peptide 2, insulin-like growth factor 1, erythropoietin, growth hormone, and hepatocyte growth factor in necrotizing enterocolitis are summarized in this article.
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Affiliation(s)
- Rita D. Shelby
- Surgical Research Fellow, Department of Pediatric Surgery, Nationwide Children’s Hospital, Center for Perinatal Research, the Research Institute at Nationwide Children’s Hospital, The Ohio State University College of Medicine, Columbus, OH
| | - Barrett Cromeens
- Surgical Research Fellow, Department of Pediatric Surgery, Nationwide Children’s Hospital, Center for Perinatal Research, the Research Institute at Nationwide Children’s Hospital, The Ohio State University College of Medicine, Columbus, OH
| | - Terrance M Rager
- Surgical Research Fellow, Department of Pediatric Surgery, Nationwide Children’s Hospital, Center for Perinatal Research, the Research Institute at Nationwide Children’s Hospital, The Ohio State University College of Medicine, Columbus, OH
| | - Gail E. Besner
- Chief, Department of Pediatric Surgery, H. William Clatworthy, Jr. Professor of Surgery, Department of Pediatric Surgery, Nationwide Children’s Hospital, Center for Perinatal Research, the Research Institute at Nationwide Children’s Hospital, The Ohio State University College of Medicine, Columbus, OH
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18
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Zhang T, Shi L, Xu Y, Li Y, Li S, Guan B, Qi Z, Zhang Y, Liu L. Purified PEGylated human glucagon-like peptide-2 reduces the severity of irradiation-induced acute radiation enteritis in rats. JOURNAL OF RADIATION RESEARCH 2019; 60:7-16. [PMID: 30247656 PMCID: PMC6373673 DOI: 10.1093/jrr/rry076] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/02/2018] [Revised: 05/08/2018] [Indexed: 06/08/2023]
Abstract
Radiation-induced acute intestinal injury after abdominal and pelvic irradiation is a common and serious problem in the clinical setting. Glucagon-like peptide-2 (GLP-2), a 33-amino acid peptide, exerts diverse effects related to the regulation of gastrointestinal growth and function. However, GLP-2 is relatively unstable in vivo. The aim of the present study was to improve GLP-2 stability in vivo and to evaluate its therapeutic effect on acute radiation enteritis. We generated long-lasting intestinal protection peptides by conjugating human GLP-2 (hGLP-2) peptides to polyethyleneglycol (PEG) to produce mPEGylation hGLP-2 (Mono-PEG-hGLP-2) through an enzymatic site-specific transglutamination reaction. Mono-PEG-hGLP-2 synthesized under optimal reaction conditions and separated by one-step ion-exchange chromatography was found to be resistant to degradation in vitro. Pretreatment with Mono-PEG-hGLP-2 reduced the severity of radiation-induced intestinal injury, oxidative stress, and the expression of NF-κB in rats with irradiation-induced acute radiation enteritis. The enhanced biological potency of Mono-PEG-hGLP-2 highlights its potential as a therapeutic agent for intestinal diseases.
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Affiliation(s)
- Tian Zhang
- Department of Pharmacy, Tangdu Hospital, Fourth Military Medical University, Xi’an, PR China
| | - Lei Shi
- Department of Pharmacy, Tangdu Hospital, Fourth Military Medical University, Xi’an, PR China
| | - Yuan Xu
- Department of Pharmacy, Tangdu Hospital, Fourth Military Medical University, Xi’an, PR China
| | - Yang Li
- Department of Pharmacy, Tangdu Hospital, Fourth Military Medical University, Xi’an, PR China
| | - Shicao Li
- Department of Pharmacy, Tangdu Hospital, Fourth Military Medical University, Xi’an, PR China
| | - Bo Guan
- Department of Pharmacy, Tangdu Hospital, Fourth Military Medical University, Xi’an, PR China
| | - Zhihua Qi
- Department of Pharmacy, Tangdu Hospital, Fourth Military Medical University, Xi’an, PR China
| | - Ye Zhang
- Department of Infectious Diseases, Tangdu Hospital, Fourth Military Medical University, Xi’an, PR China
| | - Linna Liu
- Department of Pharmacy, Tangdu Hospital, Fourth Military Medical University, Xi’an, PR China
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Wismann P, Pedersen SL, Hansen G, Mannerstedt K, Pedersen PJ, Jeppesen PB, Vrang N, Fosgerau K, Jelsing J. Novel GLP-1/GLP-2 co-agonists display marked effects on gut volume and improves glycemic control in mice. Physiol Behav 2018. [PMID: 29540315 DOI: 10.1016/j.physbeh.2018.03.004] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
AIM Analogues of several gastrointestinal peptide hormones have been developed into effective medicines for treatment of diseases such as type 2 diabetes mellitus (T2DM), obesity and short bowel syndrome (SBS). In this study, we aimed to explore whether the combination of glucagon-like peptide-1 (GLP-1) and glucagon-like peptide-2 (GLP-2) into a potent co-agonist could provide additional benefits compared to existing monotherapies. METHODS A short-acting (GUB09-123) and a half-life extended (GUB09-145) GLP-1/GLP-2 co-agonist were generated using solid-phase peptide synthesis and tested for effects on food intake, body weight, glucose homeostasis, and gut proliferation in lean mice and in diabetic db/db mice. RESULTS Sub-chronic administration of GUB09-123 to lean mice significantly reduced food intake, improved glucose tolerance, and increased gut volume, superior to monotherapy with the GLP-2 analogue teduglutide. Chronic administration of GUB09-123 to diabetic mice significantly improved glycemic control and showed persistent effects on gastric emptying, superior to monotherapy with the GLP-1 analogue liraglutide. Due to the short-acting nature of the molecule, no effects on body weight were observed, whereas a marked and robust intestinotrophic effect on mainly the small intestine volume and surface area was obtained. In contrast to GUB09-123, sub-chronic administration of a half-life extended GUB09-145 to lean mice caused marked dose-dependent effects on body weight while maintaining its potent intestinotrophic effect. CONCLUSION Our data demonstrate that the GLP-1/GLP-2 co-agonists have effects on gut morphometry, showing a marked increase in intestinal volume and mucosal surface area. Furthermore, effects on glucose tolerance and long-term glycemic control are evident. Effects on body weight and gastric emptying are also observed depending on the pharmacokinetic properties of the molecule. We suggest that this novel co-agonistic approach could exemplify a novel concept for treatment of T2DM or SBS.
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Affiliation(s)
| | | | - Gitte Hansen
- Gubra ApS, Hørsholm Kongevej 11B, Hørsholm, DK-2970, Denmark
| | | | | | - Palle B Jeppesen
- Rigshospitalet CA-2121, Blegdamsvej 9, Copenhagen DK-2100, Denmark
| | - Niels Vrang
- Gubra ApS, Hørsholm Kongevej 11B, Hørsholm, DK-2970, Denmark
| | - Keld Fosgerau
- Gubra ApS, Hørsholm Kongevej 11B, Hørsholm, DK-2970, Denmark
| | - Jacob Jelsing
- Gubra ApS, Hørsholm Kongevej 11B, Hørsholm, DK-2970, Denmark
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20
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Worthington JJ, Reimann F, Gribble FM. Enteroendocrine cells-sensory sentinels of the intestinal environment and orchestrators of mucosal immunity. Mucosal Immunol 2018; 11:3-20. [PMID: 28853441 DOI: 10.1038/mi.2017.73] [Citation(s) in RCA: 162] [Impact Index Per Article: 23.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2017] [Accepted: 07/14/2017] [Indexed: 02/06/2023]
Abstract
The intestinal epithelium must balance efficient absorption of nutrients with partitioning commensals and pathogens from the bodies' largest immune system. If this crucial barrier fails, inappropriate immune responses can result in inflammatory bowel disease or chronic infection. Enteroendocrine cells represent 1% of this epithelium and have classically been studied for their detection of nutrients and release of peptide hormones to mediate digestion. Intriguingly, enteroendocrine cells are the key sensors of microbial metabolites, can release cytokines in response to pathogen associated molecules and peptide hormone receptors are expressed on numerous intestinal immune cells; thus enteroendocrine cells are uniquely equipped to be crucial and novel orchestrators of intestinal inflammation. In this review, we introduce enteroendocrine chemosensory roles, summarize studies correlating enteroendocrine perturbations with intestinal inflammation and describe the mechanistic interactions by which enteroendocrine and mucosal immune cells interact during disease; highlighting this immunoendocrine axis as a key aspect of innate immunity.
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Affiliation(s)
- J J Worthington
- Lancaster University, Faculty of Health and Medicine, Division of Biomedical and Life Sciences, Lancaster, Lancashire, UK
| | - F Reimann
- University of Cambridge, Metabolic Research Laboratories, Wellcome Trust/MRC Institute of Metabolic Science & MRC Metabolic Diseases Unit, Addenbrooke's Hospital, Cambridge, UK
| | - F M Gribble
- University of Cambridge, Metabolic Research Laboratories, Wellcome Trust/MRC Institute of Metabolic Science & MRC Metabolic Diseases Unit, Addenbrooke's Hospital, Cambridge, UK
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Wang S, Qin C. Interleukin 35 Rescues Regulatory B Cell Function, but the Effect Is Dysregulated in Ulcerative Colitis. DNA Cell Biol 2017; 36:413-421. [PMID: 28398870 DOI: 10.1089/dna.2016.3570] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Affiliation(s)
- Shaoxuan Wang
- Department of Gastroenterology, Shandong Provincial Hospital Affiliated to Shandong University, Jinan, China
- Department of Gastroenterology, The First People's Hospital of Jining, Jining, China
| | - Chengyong Qin
- Department of Gastroenterology, Shandong Provincial Hospital Affiliated to Shandong University, Jinan, China
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22
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Karrasch T, Schaeffler A. Adipokines and the role of visceral adipose tissue in inflammatory bowel disease. Ann Gastroenterol 2016; 29:424-438. [PMID: 27708507 PMCID: PMC5049548 DOI: 10.20524/aog.2016.0077] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/19/2016] [Accepted: 07/22/2016] [Indexed: 12/20/2022] Open
Abstract
Recently, adipocytes have been recognized as actively participating in local and systemic immune responses via the secretion of peptides detectable in relevant levels in the systemic circulation, the so-called "adipo(cyto)kines". Multiple studies appearing within the last 10-15 years have focused on the possible impact of adipose tissue depots on inflammatory bowel disease (IBD). Consequently, various hypotheses regarding the role of different adipokines in inflammatory diseases in general and in intestinal inflammatory processes in particular have been developed and have been further refined in recent years. After a focused summary of the data reported concerning the impact of visceral adipose tissue on IBD, such as Crohn's disease and ulcerative colitis, our review focuses on recent developments indicating that adipocytes as part of the innate immune system actively participate in antimicrobial host defenses in the context of intestinal bacterial translocation, which are of utmost importance for the homeostasis of the whole organism. Modulators of adipose tissue function and regulators of adipokine secretion, as well as modifiers of adipocytic pattern recognition molecules, might represent future potential drug targets in IBD.
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Affiliation(s)
- Thomas Karrasch
- Department of Internal Medicine III, Giessen University Hospital, Germany
| | - Andreas Schaeffler
- Department of Internal Medicine III, Giessen University Hospital, Germany
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Zietek T, Rath E. Inflammation Meets Metabolic Disease: Gut Feeling Mediated by GLP-1. Front Immunol 2016; 7:154. [PMID: 27148273 PMCID: PMC4840214 DOI: 10.3389/fimmu.2016.00154] [Citation(s) in RCA: 90] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2016] [Accepted: 04/08/2016] [Indexed: 12/14/2022] Open
Abstract
Chronic diseases, such as obesity and diabetes, cardiovascular, and inflammatory bowel diseases (IBD) share common features in their pathology. Metabolic disorders exhibit strong inflammatory underpinnings and vice versa, inflammation is associated with metabolic alterations. Next to cytokines and cellular stress pathways, such as the unfolded protein response (UPR), alterations in the enteroendocrine system are intersections of various pathologies. Enteroendocrine cells (EEC) have been studied extensively for their ability to regulate gastrointestinal motility, secretion, and insulin release by release of peptide hormones. In particular, the L-cell-derived incretin hormone glucagon-like peptide 1 (GLP-1) has gained enormous attention due to its insulinotropic action and relevance in the treatment of type 2 diabetes (T2D). Yet, accumulating data indicate a critical role for EEC and in particular for GLP-1 in metabolic adaptation and in orchestrating immune responses beyond blood glucose control. EEC sense the lamina propria and luminal environment, including the microbiota via receptors and transporters. Subsequently, mediating signals by secreting hormones and cytokines, EEC can be considered as integrators of metabolic and inflammatory signaling. This review focuses on L cell and GLP-1 functions in the context of metabolic and inflammatory diseases. The effects of incretin-based therapies on metabolism and immune system are discussed and the interrelation and common features of metabolic and immune-mediated disorders are highlighted. Moreover, it presents data on the impact of inflammation, in particular of IBD on EEC and discusses the potential role of the microbiota as link between nutrients, metabolism, immunity, and disease.
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Affiliation(s)
- Tamara Zietek
- Department of Nutritional Physiology, Technische Universität München , Freising , Germany
| | - Eva Rath
- Chair of Nutrition and Immunology, Technische Universität München , Freising , Germany
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Wiśniewski K, Sueiras-Diaz J, Jiang G, Galyean R, Lu M, Thompson D, Wang YC, Croston G, Posch A, Hargrove DM, Wiśniewska H, Laporte R, Dwyer JJ, Qi S, Srinivasan K, Hartwig J, Ferdyan N, Mares M, Kraus J, Alagarsamy S, Rivière PJM, Schteingart CD. Synthesis and Pharmacological Characterization of Novel Glucagon-like Peptide-2 (GLP-2) Analogues with Low Systemic Clearance. J Med Chem 2016; 59:3129-39. [DOI: 10.1021/acs.jmedchem.5b01909] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Affiliation(s)
- Kazimierz Wiśniewski
- Ferring
Research Institute Inc., 4245 Sorrento
Valley Boulevard, San Diego, California 92121, United States
| | - Javier Sueiras-Diaz
- Ferring
Research Institute Inc., 4245 Sorrento
Valley Boulevard, San Diego, California 92121, United States
| | - Guangcheng Jiang
- Ferring
Research Institute Inc., 4245 Sorrento
Valley Boulevard, San Diego, California 92121, United States
| | - Robert Galyean
- Ferring
Research Institute Inc., 4245 Sorrento
Valley Boulevard, San Diego, California 92121, United States
| | - Mark Lu
- Ferring
Research Institute Inc., 4245 Sorrento
Valley Boulevard, San Diego, California 92121, United States
| | - Dorain Thompson
- Ferring
Research Institute Inc., 4245 Sorrento
Valley Boulevard, San Diego, California 92121, United States
| | - Yung-Chih Wang
- Ferring
Research Institute Inc., 4245 Sorrento
Valley Boulevard, San Diego, California 92121, United States
| | - Glenn Croston
- Ferring
Research Institute Inc., 4245 Sorrento
Valley Boulevard, San Diego, California 92121, United States
| | - Alexander Posch
- Ferring
Research Institute Inc., 4245 Sorrento
Valley Boulevard, San Diego, California 92121, United States
| | - Diane M. Hargrove
- Ferring
Research Institute Inc., 4245 Sorrento
Valley Boulevard, San Diego, California 92121, United States
| | - Halina Wiśniewska
- Ferring
Research Institute Inc., 4245 Sorrento
Valley Boulevard, San Diego, California 92121, United States
| | - Régent Laporte
- Ferring
Research Institute Inc., 4245 Sorrento
Valley Boulevard, San Diego, California 92121, United States
| | - John J. Dwyer
- Ferring
Research Institute Inc., 4245 Sorrento
Valley Boulevard, San Diego, California 92121, United States
| | - Steve Qi
- Ferring
Research Institute Inc., 4245 Sorrento
Valley Boulevard, San Diego, California 92121, United States
| | - Karthik Srinivasan
- Ferring
Research Institute Inc., 4245 Sorrento
Valley Boulevard, San Diego, California 92121, United States
| | - Jennifer Hartwig
- Ferring
Research Institute Inc., 4245 Sorrento
Valley Boulevard, San Diego, California 92121, United States
| | - Nicky Ferdyan
- Ferring
Research Institute Inc., 4245 Sorrento
Valley Boulevard, San Diego, California 92121, United States
| | - Monica Mares
- Ferring
Research Institute Inc., 4245 Sorrento
Valley Boulevard, San Diego, California 92121, United States
| | - John Kraus
- Ferring
Research Institute Inc., 4245 Sorrento
Valley Boulevard, San Diego, California 92121, United States
| | - Sudarkodi Alagarsamy
- Ferring
Research Institute Inc., 4245 Sorrento
Valley Boulevard, San Diego, California 92121, United States
| | - Pierre J. M. Rivière
- Ferring
Research Institute Inc., 4245 Sorrento
Valley Boulevard, San Diego, California 92121, United States
| | - Claudio D. Schteingart
- Ferring
Research Institute Inc., 4245 Sorrento
Valley Boulevard, San Diego, California 92121, United States
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Nakame K, Kaji T, Mukai M, Shinyama S, Matsufuji H. The protective and anti-inflammatory effects of glucagon-like peptide-2 in an experimental rat model of necrotizing enterocolitis. Peptides 2016; 75:1-7. [PMID: 26551873 DOI: 10.1016/j.peptides.2015.07.025] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/21/2015] [Revised: 07/21/2015] [Accepted: 07/21/2015] [Indexed: 12/12/2022]
Abstract
Necrotizing enterocolitis (NEC) is a devastating gastrointestinal disease, that affects premature infants. Glucagon-like peptide-2 (GLP-2) is an intestinotrophic hormone and reduces the inflammation. We suspected that GLP-2 would have protective and anti-inflammatory effects in an experimental rat model of NEC. NEC was induced in newborn rats by enteral feeding with hyperosmolar formula, asphyxial stress and enteral administration of lipopolysaccharide (LPS). Rats were randomly divided into the following four groups: dam-fed, NEC, NEC+GLP-2(L) given 80 μg/kg/day of GLP-2, and NEC+GLP-2(H) given 800 μg/kg/day of GLP-2. GLP-2 was administered subcutaneously every 6 h before stress. All animals surviving beyond 96 h or any that developed signs of distress were euthanized. The clinical sickness score in the NEC+GLP-2(H) group was significantly lower than that in the NEC group. The NEC score and the survival rate in the NEC+GLP-2(H) group was significantly improved compared with those in the NEC and the NEC+GLP-2(L) groups. Villous height and crypt depth in both the GLP-2 treatment groups were significantly increased compared with those in the NEC group. There were no significant differences in the crypt cell proliferation indices among the groups. Ileal interstitial TNF-α and IL-6 level in the NEC+GLP-2(H) group was decreased to the same levels in the dam-fed group. High dose GLP-2 administration improved the incidence and survival rate for NEC. It also decreased mucosal inflammatory cytokine production. These results support a potential therapeutic role for GLP-2 in the treatment of NEC.
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Affiliation(s)
- Kazuhiko Nakame
- Department of Pediatric Surgery, Kagoshima University Graduate, School of Medical and Dental Sciences 8-35-1, Kagoshima shi, Kagoshima 890-8520, Japan.
| | - Tatsuru Kaji
- Department of Pediatric Surgery, Kagoshima University Graduate, School of Medical and Dental Sciences 8-35-1, Kagoshima shi, Kagoshima 890-8520, Japan
| | - Motoi Mukai
- Department of Pediatric Surgery, Kagoshima University Graduate, School of Medical and Dental Sciences 8-35-1, Kagoshima shi, Kagoshima 890-8520, Japan
| | - Shin Shinyama
- Department of Pediatric Surgery, Kagoshima University Graduate, School of Medical and Dental Sciences 8-35-1, Kagoshima shi, Kagoshima 890-8520, Japan
| | - Hiroshi Matsufuji
- Department of Pediatric Surgery, St Luke's International Hospital 9-1, Akashi-cho, Chuo-ku, Tokyo 104-8560, Japan
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26
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Gulec Suyen G, Isbil-Buyukcoskun N, Cam B, Ozluk K. Effects of centrally injected glucagon-like peptide-2 on gastric mucosal blood flow in rats: possible mechanisms. Peptides 2015; 64:62-6. [PMID: 25596156 DOI: 10.1016/j.peptides.2014.12.008] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/27/2014] [Revised: 10/30/2014] [Accepted: 12/01/2014] [Indexed: 01/02/2023]
Abstract
"Glucagon-like peptide-2" (GLP-2) is a peptide that is released from the enteroendocrine L cells in response to food in the gastrointestinal tract. Peripheral injection of GLP-2 has been shown to increase gastrointestinal blood flow, but effects of central GLP-2 on any vascular bed has not been studied yet. The aim of this study is to investigate the effects of various doses of intracerebroventricularly (i.c.v.)-injected GLP-2 on gastric mucosal blood flow (GMBF) and contribution of calcitonin gene related peptide (CGRP), nitric oxide synthase-nitric oxide (NOS-NO) and cyclooxygenase-prostaglandin (COX-PG) systems to the possible effect. The gastric chamber technique was used to determine GMBF. Urethane anesthesia was used throughout the recording procedure. Male Wistar rats were treated with GLP-2 (100, 150 ve 200ng/10μl; i.c.v.) or saline (10μl; i.c.v.) in order to find out the effective dose of i.c.v. GLP-2 on GMBF. Then, CGRP receptor antagonist CGRP-(8-37) (10μg/kg; s.c.), NOS inhibitor NG-nitro-l-arginine methyl ester (l-NAME; 30mg/kg; s.c.) or COX inhibitor indomethacin (5mg/kg; i.p.) was injected before the effective dose of i.c.v. GLP-2. GMBF was measured continuously for 35min following GLP-2 and recorded every fifth minute. Non-parametric Kruskal-Wallis test was used for statistical analysis. Differences were considered to be significant at p<0.05. GMBF increased rapidly following 100ng GLP-2 injection and did not fall to the basal levels during 35min. Other doses of i.c.v. GLP-2 did not produce any significant difference in GMBF. CGRP receptor antagonist, CGRP-(8-37) (10μg/kg; s.c.) and COX inhibitor indomethacin (5mg/kg; i.p.) significantly prevented the increase in GMBF due to GLP-2 (100ng; i.c.v.), while l-NAME (30mg/kg; s.c.) was ineffective. None of the drugs produced a significant change in GMBF when administered alone. Thus we suggest that, i.c.v. GLP-2 increases GMBF and CGRP and endogenous prostaglandins but not NO, contribute to this effect.
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Affiliation(s)
- Guldal Gulec Suyen
- Acibadem University, School of Medicine, Department of Physiology, Istanbul, Turkey.
| | | | - Betul Cam
- Uludağ University, School of Medicine, Department of Physiology, Bursa, Turkey
| | - Kasim Ozluk
- Uludağ University, School of Medicine, Department of Physiology, Bursa, Turkey
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27
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Qi KK, Wu J, Xu ZW. Effects of PEGylated porcine glucagon-like peptide-2 therapy in weaning piglets challenged with lipopolysaccharide. Peptides 2014; 58:7-13. [PMID: 24874708 DOI: 10.1016/j.peptides.2014.05.007] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/18/2014] [Revised: 05/16/2014] [Accepted: 05/16/2014] [Indexed: 11/21/2022]
Abstract
This study aims to evaluate the therapeutic effect of polyethylene glycosylated porcine glucagon-like peptide-2 (pGLP-2), a long-acting form of pGLP-2, in lipopolysaccharide (LPS)-challenged piglets. Eighteen 21-day-old weaning piglets were randomly assigned into three groups: control (saline solution), LPS (100 μg/kg LPS), and PEG-pGLP-2 (10 nmol/kg PEG-pGLP-2+100 μg/kg LPS). All treatments were administered intraperitoneally. Compared with the control treatment, LPS treatment significantly decreased (P<0.05) the villus heights of the duodenum and jejunum, as well as the villus height/crypt depth ratio of the jejunum. However, PEG-pGLP-2 therapy reduced these effects (P>0.05). Specifically, PEG-pGLP-2 infusion significantly increased the villus height/crypt depth ratio of the duodenum (P<0.05) compared with LPS treatment. Compared with the control treatment, LPS treatment significantly increased (P<0.05) the mRNA expression levels of interferon-γ (IFN-γ) and tumor necrosis factor-α (TNF-α) in the jejunum. However, PEG-pGLP-2 therapy reduced these effects (P<0.05). Specifically, PEG-pGLP-2 infusion significantly decreased (P<0.05) the mRNA expression levels of interleukin (IL)-8 and TNF-α in the duodenum and jejunum, IL-10 in the duodenum, and IFN-γ in the jejunum compared with the LPS treatment. LPS treatment increased the caspase-3 activity of the ileum mucosal (P<0.05), and this effect was significantly reduced by PEG-pGLP-2 treatment. These results indicate that PEG-pGLP-2 infusion alleviates the severity of intestinal injury in weaning piglets by reducing the secretion of inflammatory cytokines and the caspase-3 activity, and increasing the villus height/crypt depth ratio.
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Affiliation(s)
- Ke-ke Qi
- Institute of Animal Science, Zhejiang Academy of Agricultural Sciences, Hangzhou 310021, People's Republic of China
| | - Jie Wu
- Institute of Animal Science, Zhejiang Academy of Agricultural Sciences, Hangzhou 310021, People's Republic of China
| | - Zi-wei Xu
- Institute of Animal Science, Zhejiang Academy of Agricultural Sciences, Hangzhou 310021, People's Republic of China.
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28
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Qi KK, Wu J, Wan J, Men XM, Xu ZW. Purified PEGylated porcine glucagon-like peptide-2 reduces the severity of colonic injury in a murine model of experimental colitis. Peptides 2014; 52:11-8. [PMID: 24274971 DOI: 10.1016/j.peptides.2013.11.012] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/09/2013] [Revised: 11/14/2013] [Accepted: 11/14/2013] [Indexed: 10/26/2022]
Abstract
The rapid degradation of porcine glucagon-like peptide-2 (pGLP-2) by the enzyme dipeptidyl peptidase-IV (DPP-IV) is the main impediment in the development of pGLP-2 as a potential therapeutic agent for intestinal dysfunction and damage. In this study, one mono-modified Lys(30)-polyethylene glycol (PEG)-pGLP-2 was prepared using mPEG-succinimidyl propionate. To determine the optimized condition for PEGylation, the reactions were monitored by RP-HPLC and MALDI-TOF-MS. Stability was tested in purified DPP-IV in vitro. In vivo, the protective effects for colonic injury were measured in dextran sulfate sodium (DSS)-induced colitis in mice. The monoPEGylated products reached the maximum yield at 4:1 ratio of mPEG5k-SPA to pGLP-2. An effective method of successfully separating PEGylated pGLP-2 from mPEG-SPA5kD using CM Sepharose Fast Flow resin was established. The half-life of Lys(30)-PEG-pGLP-2 was 16-fold longer than that of pGLP-2 in DPP-IV. The DSS mice exhibited marked weight loss), which was significantly reduced by Lys(30)-PEG-pGLP-2 therapy. DSS treatment significantly increased colonic damage score, which was significantly reduced by administration of Lys(30)-PEG-pGLP-2 in DSS-mice. DSS-induced colitis clearly induced Myeloperoxidase activity in the colon, which was significantly reduced by treatments with 3% DSS-pGLP-2 or 3% DSS-PEG-pGLP-2. These results showed that site-specific Lys(30)-PEG-GLP-2 was resistant to degradation and reduced the severity of colonic injury in murine colitis. The enhanced biological potency of this product highlighted its potential as a therapeutic agent for intestinal diseases.
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Affiliation(s)
- Ke-ke Qi
- Institute of Animal Science, Zhejiang Academy of Agricultural Sciences, Hangzhou 310021, China
| | - Jie Wu
- Institute of Animal Science, Zhejiang Academy of Agricultural Sciences, Hangzhou 310021, China
| | - Jing Wan
- Institute of Animal Science, Zhejiang Academy of Agricultural Sciences, Hangzhou 310021, China
| | - Xiao-ming Men
- Institute of Animal Science, Zhejiang Academy of Agricultural Sciences, Hangzhou 310021, China
| | - Zi-wei Xu
- Institute of Animal Science, Zhejiang Academy of Agricultural Sciences, Hangzhou 310021, China.
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Abstract
BACKGROUND Glucagon-like peptide-2 (GLP-2) has been suggested for the treatment of mucositis, but the peptide has also been shown to accentuate colonic dysplasia in carcinogen-treated mice. Recently, an effect on intestinal growth was discovered for glucagon-like peptide-1 (GLP-1), OBJECTIVE: To determine whether endogenous GLP-1 contributes to the healing processes and if exogenous GLP-1 has a potential role in treating mucositis. METHODS Mice were injected with 5-fluorouracil (5-FU) or saline to induce mucositis and were then treated with GLP-1, GLP-2, GLP-2 (3-33), exendin (9-39) or vehicle. The mice were sacrificed 48 or 96 h after the 5-FU injections. The end points were intestinal weight, villus height, proliferation and histological scoring of mucositis severity. Rats were injected with 5-FU or saline, and after 48 h, blood was drawn and analysed for GLP-1 and GLP-2 concentration. RESULTS GLP-1 and GLP-2 significantly prevented the loss of mucosal mass and villus height and significantly decreased the mucositis severity score in the duodenum and jejunum 48 h after chemotherapy. The effect was equivalent. Exendin (9-39) reduced the intestinal weight 96 h after chemotherapy. The GLP-1 levels in blood were increased more than 10-fold, and GLP-2 levels were increased sevenfold. CONCLUSIONS GLP-1 and GLP-2 were secreted after intestinal injury, and recovery was delayed after treatment with exendin (9-39), indicating an important role for the peptides in the protection of the intestine from injury. GLP-1 treatment ameliorated mucositis, which suggests that mucositis and other acute intestinal disorders might benefit from treatment with GLP-1 analogues.
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Affiliation(s)
- Hannelouise Kissow
- Department of Biomedical Sciences and the Novo Nordisk Foundation Center for Basic Metabolic Research, University of Copenhagen, Copenhagen, Denmark
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Abstract
OBJECTIVES Necrotizing enterocolitis (NEC) is complex disease thought to occur as a result of an immaturity of the gastrointestinal tract of preterm infants. Intestinal dysfunction induced by total parental nutrition (TPN) may increase the risk for NEC upon introduction of enteral feeding. We hypothesized that the intestinal trophic and anti-inflammatory actions previously ascribed to the gut hormone, glucagon-like peptide-2 (GLP-2), would reduce the incidence of NEC when given in combination with TPN in preterm piglets. METHODS Preterm, newborn piglets were nourished by TPN and infused continuously with either human GLP-2 (100 μg · kg⁻¹ · day⁻¹) or control saline for 2 days (n = 12/group). On day 3, TPN was discontinued and pigs were given orogastric formula feeding every 3 hours, and continued GLP-2 or control treatment until the onset of clinical signs of NEC for an additional 96 hours and tissue was collected for molecular and histological endpoints. RESULTS GLP-2 treatment delayed the onset of NEC but was unable to prevent a high NEC incidence (~70%) and severity that occurred in both groups. GLP-2-treated pigs had less histological injury and increased proximal intestinal weight and mucosal villus height, but not crypt depth or Ki-67-positive cells. Inflammatory markers of intestinal myeloperoxidase were unchanged and serum amyloid A levels were higher in GLP-2-treated pigs. CONCLUSIONS GLP-2 did not prevent NEC and a proinflammatory response despite some reduction in mucosal injury and increased trophic effect.
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31
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Liu Y, Ipharraguerre IR, Pettigrew JE. Digestive physiology of the pig symposium: potential applications of knowledge of gut chemosensing in pig production. J Anim Sci 2013; 91:1982-90. [PMID: 23408810 DOI: 10.2527/jas.2012-6193] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Pig production is a commodity business, which makes it a cost-driven business. Pig producers and their advisors are appropriately reluctant to adopt technologies without confidence that improved production will more than pay for the cost of the technology. Physiological effects of technologies targeting gut sensory pathways must translate to demonstrably improved health and/or productive performance if they are to be adopted. The types and degrees of stressors experienced by pigs in commercial production vary widely and often differ from those in research herds, and those variations influence their productive responses to nutritional and health technologies. Pigs are most vulnerable to disease soon after weaning, and the diets fed to pigs at that time are more expensive and offered in much smaller amounts than those fed later in life. Those factors make it easier to justify expensive dietary technologies for young pigs than for older ones. New developments in gut chemosensing appear important, but their practical application is not yet clear. We suggest investigation of the potential to connect chemical detection by the gut to pig productivity and/or efficiency through these mechanisms: 1) trophic effects on the intestines, which lead to improved enteric health or enhanced nutrient digestion and absorption, 2) enhanced barrier function in the intestinal mucosa, 3) increased feed intake, 4) enhanced insulin secretion and sensitivity, which may be especially useful in lactating sows to improve subsequent reproduction, and 5) other signals triggered by products of enteric fermentation, possibly short-chain fatty acids, that may influence gut integrity, feed intake, and reproductive function. Each of these mechanisms relates to a practical issue in pig production. Practical application would likely be achieved through dietary changes, but separate management factors, drugs, or other interventions may also be developed.
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Affiliation(s)
- Y Liu
- Department of Animal Sciences, University of Illinois, Urbana, IL 60801, USA
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32
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Katz MS, Thatch KA, Schwartz MZ. Gene alterations and intestinal mucosal changes following growth factor and omega-3 exposure in a rat model of inflammatory bowel disease. J Pediatr Surg 2013; 48:345-52. [PMID: 23414863 DOI: 10.1016/j.jpedsurg.2012.11.013] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/07/2012] [Accepted: 11/12/2012] [Indexed: 01/25/2023]
Abstract
BACKGROUND We have previously shown that there is synergism between Hepatocyte Growth Factor (HGF) and Omega-3 (OM-3) enriched feeds using an immunologic model of inflammatory bowel disease (IBD). This combination decreased inflammation and cytokine levels and increased microvascular density and mucosal mass. This study evaluates the gene alterations that occurred using this same model. METHODS Twenty adult female transgenic HLA-B27 rats were divided into four groups: Group 1: (Regular feeds, IV saline); Group 2: (OM-3 feeds, IV saline); Group 3: (Regular feeds, IV HGF 150 μg/kg/day); Group 4: (OM-3 feeds, IV HGF 150 μg/kg/day). Rats were sacrificed 14 days after pump placement. Bowel was harvested and RNA extracted. Microarray gene chips were used. Statistical analysis was done by analysis of variance using Partek Genomics Suite. Results were significant if fold change was more than 2 or less than -2, with P<0.05. RESULTS In the ileum, HGF up- or down-regulated 34 genes, while OM-3 affected 60 genes. Together 68 genes were affected. Families with a synergistic effect included Solute Carrier Proteins, ATP Binding Cassette Proteins, and Matrix Metalloproteinases. In the colon, 23 genes were affected by HGF, while 66 genes were affected with OM-3. Combined exposure affected 32 genes, including a synergistic effect on solute carrier proteins, aquaporins, and immunologic factors. CONCLUSIONS There is a synergistic gene alteration effect of exposure of two (HGF and Omega-3 enriched feeds) agents on bowel mucosa. Of most interest was the synergistic effect on the solute carrier protein family, a previously identified gene family up-regulated in response to intestinal failure.
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Affiliation(s)
- Michael S Katz
- Department of Pediatric General, Thoracic and Minimally Invasive Surgery, St. Christopher's Hospital for Children and Drexel University College of Medicine, Philadelphia, PA, USA
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33
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Wilke VL, Nettleton D, Wymore MJ, Gallup JM, Demirkale CY, Ackermann MR, Tuggle CK, Ramer-Tait AE, Wannemuehler MJ, Jergens AE. Gene expression in intestinal mucosal biopsy specimens obtained from dogs with chronic enteropathy. Am J Vet Res 2012; 73:1219-29. [PMID: 22849683 DOI: 10.2460/ajvr.73.8.1219] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
OBJECTIVE To characterize mucosal gene expression in dogs with chronic enteropathy (CE). ANIMALS 18 dogs with CE and 6 healthy control dogs. PROCEDURES Small intestinal mucosal biopsy specimens were endoscopically obtained from dogs. Disease severity in dogs with CE was determined via inflammatory bowel index scores and histologic grading of biopsy specimens. Total RNA was extracted from biopsy specimens and microchip array analysis (approx 43,000 probe sets) and quantitative reverse transcriptase PCR assays were performed. RESULTS 1,875 genes were differentially expressed between dogs with CE and healthy control dogs; 1,582 (85%) genes were downregulated in dogs with CE, including neurotensin, fatty acid-binding protein 6, fatty acid synthase, aldehyde dehydrogenase 1 family member B1, metallothionein, and claudin 8, whereas few genes were upregulated in dogs with CE, including genes encoding products involved in extracellular matrix degradation (matrix metallopeptidases 1, 3, and 13), inflammation (tumor necrosis factor, interleukin-8, peroxisome proliferator-activated receptor γ, and S100 calcium-binding protein G), iron transport (solute carrier family 40 member 1), and immunity (CD96 and carcinoembryonic antigen-related cell adhesion molecule [CEACAM] 18). Dogs with CE and protein-losing enteropathy had the greatest number of differentially expressed genes. Results of quantitative reverse transcriptase PCR assay for select genes were similar to those for microchip array analysis. CONCLUSIONS AND CLINICAL RELEVANCE Expression of genes encoding products regulating mucosal inflammation was altered in dogs with CE and varied with disease severity. Impact for Human Medicine-Molecular pathogenesis of CE in dogs may be similar to that in humans with inflammatory bowel disease.
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Affiliation(s)
- Vicki L Wilke
- Department of Veterinary Clinical Sciences, College of Veterinary Medicine, University of Minnesota, Saint Paul, MN 55108, USA
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Abstract
OBJECTIVES Glucagon-like peptide 2 (GLP2) is an intestinal growth factor that has been shown to stimulate intestinal growth and reduce disease severity in preclinical models of short bowel syndrome and inflammatory bowel disease. Teduglutide, a recombinant human GLP2 variant (GLP2-2G), has increased half-life and stability as compared to the native GLP2 peptide, but still requires twice daily dosing in preclinical models and daily dosing in the clinic. The goal of this study was to produce and characterize the preclinical pharmacokinetic and therapeutic properties of GLP2-2G-XTEN, a novel, long-acting form of GLP2-2G. METHODOLOGY AND RESULTS A GLP2-2G-XTEN fusion protein with extended exposure profile was produced by genetic fusion of GLP2-2G peptide to XTEN, a long, unstructured, non-repetitive, hydrophilic sequence of amino acids. The serum half-life of GLP2-2G-XTEN in mice, rats and monkeys was 34, 38 and 120 hours, respectively. Intestinotrophic effects were demonstrated in normal rats, where GLP2-2G-XTEN administration resulted in a significant increase in both small intestine weight and length. Efficacy of the GLP2-2G-XTEN protein was compared to that of GLP2-2G peptide in a rat Crohn's disease model, indomethacin-induced inflammation. Prophylactic administration of GLP2-2G-XTEN significantly increased the length, reduced the number of trans-ulcerations and adhesions, and reduced the TNFα content of the small intestine. GLP2-2G-XTEN demonstrated greater in vivo potency as compared to GLP2-2G peptide, and improvement in histopathology supported the GLP2-2G-XTEN treatment effects. CONCLUSIONS AND SIGNIFICANCE GLP2-2G-XTEN is intestinotrophic and demonstrates efficacy in a rat Crohn's disease model requiring a lower molar dose and less frequent dosing relative to GLP2-2G peptide. Allometric scaling based on pharmacokinetics from mouse, rat and monkey projects a human half-life of 240 hours. These improvements in preclinical pharmacokinetics and dosing indicate that GLP2-2G-XTEN may offer a superior therapeutic benefit for treatment of gastrointestinal diseases including Crohn's disease.
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Körner M, Rehmann R, Reubi JC. GLP-2 receptors in human disease: high expression in gastrointestinal stromal tumors and Crohn's disease. Mol Cell Endocrinol 2012; 364:46-53. [PMID: 22951144 DOI: 10.1016/j.mce.2012.08.008] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/18/2012] [Revised: 08/13/2012] [Accepted: 08/13/2012] [Indexed: 12/22/2022]
Abstract
Peptide hormones of the glucagon-like peptide (GLP) family play an increasing clinical role, as reported for GLP-1 in diabetes therapy and insulinoma diagnostics. GLP-2, despite its known trophic and anti-inflammatory intestinal actions translated into preliminary clinical studies using the GLP-2 analogue teduglutide for treatment of short bowel syndrome and Crohn's disease, remains poorly characterized in terms of expression of its receptor in tissues of interest. Therefore, the GLP-2 receptor expression was assessed in 237 tumor and 148 non-neoplastic tissue samples with in vitro receptor autoradiography. A GLP-2 receptor expression was present in 68% of gastrointestinal stromal tumors (GIST). Furthermore, GLP-2 receptors were identified in the intestinal myenteric plexus, with significant up-regulation in active Crohn's disease. The GLP-2 receptors in GIST may be used for clinical applications like in vivo targeting with radiolabelled GLP-2 analogues for imaging and therapy. Moreover, the over-expressed GLP-2 receptor in the myenteric plexus may represent the morphological correlate of the clinical target of teduglutide in Crohn's disease.
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Affiliation(s)
- Meike Körner
- Division of Cell Biology and Experimental Cancer Research, Institute of Pathology, University of Berne, Berne, Switzerland.
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Voortman T, Hendriks HFJ, Witkamp RF, Wortelboer HM. Effects of long- and short-chain fatty acids on the release of gastrointestinal hormones using an ex vivo porcine intestinal tissue model. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2012; 60:9035-9042. [PMID: 22757966 DOI: 10.1021/jf2045697] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Gastrointestinal (GI) peptide hormones play an important role in short-term regulation of food intake and blood glucose levels. Modulating their release is of potential relevance for weight management and possibly diabetes. As currently available models are hard to extrapolate to the human situation, the use of porcine intestinal tissue, collected from slaughter pigs, was investigated for this purpose. Intestinal tissue disks showed a predicted regional release pattern of GI peptides. Various long-chain fatty acids differentially stimulated release of glucagon-like peptide 1 (GLP-1) (up to 500%) and glucagon-like peptide 2 (GLP-2) (up to 200%) from ileal tissue disks, but effects on peptide YY (PYY) did not reach significance. Short-chain fatty acids had no effects on the release of GLP-1, GLP-2, and PYY in either the ileum or colon. In conclusion, this porcine tissue model shows to be of advantageous use in a tiered approach to study the potential of satiety-inducing compounds to be selected for studies in humans.
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Moran GW, O'Neill C, McLaughlin JT. GLP-2 enhances barrier formation and attenuates TNFα-induced changes in a Caco-2 cell model of the intestinal barrier. ACTA ACUST UNITED AC 2012; 178:95-101. [PMID: 22809889 DOI: 10.1016/j.regpep.2012.07.002] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2011] [Revised: 01/30/2012] [Accepted: 07/05/2012] [Indexed: 11/29/2022]
Abstract
INTRODUCTION Tight junctions are intercellular permeability seals that regulate paracellular transport across epithelia. Tight junction function, expression and localisation of constituent proteins are significantly altered by cytokines such as TNFα. Glucagon-like peptide-2 (GLP-2) is an intestinotrophic enteroendocrine peptide. It is not known whether GLP-2 regulates the barrier or tight junctions. The aim of this study was to investigate whether GLP-2 has an effect on tight junction function or protein expression, alone or in response to TNFα exposure. METHODS Caco-2 cells were grown to confluence on filters in the presence or absence of GLP-2. The time course of transepithelial electrical resistance developing across the monolayer was measured; tight junction protein expression was quantified by immunoblotting. At day 20, TNFα in the presence or absence of GLP-2 was added. Changes in TEER and tight junction proteins expression were quantified. Both TNFα and GLP-2 were added on the basolateral side. RESULTS GLP-2 exposed Caco-2 cell monolayers showed a significant increase in transepithelial electrical resistance compared to that in untreated control cells. At the same time, expression of the tight junction proteins occludin and zona occludens-1 (ZO-1) was increased at day 17 post-seeding (1.6-fold; p=0.037 and 4.7 fold; p=0.039 respectively). Subsequent TNFα exposure induced a significant 9.3-fold (p<0.001) decrease in transepithelial electrical resistance and a corresponding reduction in the expression of ZO-1 (5.3 fold; p<0.01). However, the TNFα-induced reduction in transepithelial electrical resistance in GLP-2-exposed cells was highly attenuated to 1.8-fold (p<0.01). No change in tight junction protein expression was noted in GLP-2 exposed cells after cytokine exposure. CONCLUSION GLP-2 enhances formation of the epithelial barrier and its constituent proteins in Caco-2 cells, and diminishes the effects of TNFα. If these effects are replicated in vivo the GLP-2 receptor may present a therapeutic target in intestinal inflammation.
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Affiliation(s)
- G W Moran
- Inflammation Sciences Research Group, University of Manchester, Manchester, M13 9PL, UK.
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Kissow H, Viby NE, Hartmann B, Holst JJ, Timm M, Thim L, Poulsen SS. Exogenous glucagon-like peptide-2 (GLP-2) prevents chemotherapy-induced mucositis in rat small intestine. Cancer Chemother Pharmacol 2012; 70:39-48. [PMID: 22729158 DOI: 10.1007/s00280-012-1882-2] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2012] [Accepted: 05/01/2012] [Indexed: 12/17/2022]
Abstract
PURPOSE Gastrointestinal mucositis is an unwanted and often dose-limiting side effect to most cancer treatments. Glucagon-like peptide-2 (GLP-2) is a peptide secreted from intestinal L-cells in response to nutrient intake. The peptide is involved in the regulation of apoptosis and proliferation in the intestine. We aimed to investigate the role of GLP-2 in experimental chemotherapy-induced mucositis. METHODS STUDY 1: Rats were given a single injection with 5-fluorouracil (5-FU) and killed in groups of five each day for 5 days. Blood samples were analysed for GLP-2 concentrations. The intestine was analysed for weight loss, morphometric estimates and proliferation. STUDY 2: Rats were treated with GLP-2 or control vehicle 2 days before a single injection of 5-FU or saline. The treatments continued until kill 2 days after. The intestine was investigated for influx of myeloperoxidase (MPO)-positive cells and morphometric estimates, such as villus height, as a marker of mucositis. RESULTS STUDY 1: Two days after chemotherapy, there was a rise in endogenous GLP-2, followed by a marked increase in proliferation. STUDY 2: Exogenous GLP-2 was able to protect the intestine from severe weight loss and completely prevented the reduction in villus height in the control rats. Furthermore, there was a significant decrease in influx of MPO-positive cells in the GLP-2-treated rats. CONCLUSION GLP-2 is secreted from the intestine in response to intestinal injury, probably explaining the compensatory hyperproliferation after chemotherapy. Exogenous GLP-2 can protect the mucosa from chemotherapy-induced mucositis in rats.
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Affiliation(s)
- Hannelouise Kissow
- Department of Biomedical Sciences, Faculty of Health Science, University of Copenhagen, Blegdamsvej 3, 2200 Copenhagen, Denmark.
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Moran GW, O'Neill C, Padfield P, McLaughlin JT. Dipeptidyl peptidase-4 expression is reduced in Crohn's disease. ACTA ACUST UNITED AC 2012; 177:40-5. [PMID: 22561447 DOI: 10.1016/j.regpep.2012.04.006] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2012] [Revised: 03/30/2012] [Accepted: 04/25/2012] [Indexed: 12/25/2022]
Abstract
BACKGROUND Dipeptidyl peptidase 4 (DP4) is a serine protease that preferentially cleaves N-terminal dipeptides from polypeptides containing proline or alanine as the penultimate amino acid. DP4 inactivates glucagon like peptide-2 (GLP-2), a trophic peptide with cytoprotective and reparative properties in the injured gut; therefore DP4 potentially inhibits repair processes. DP4 also modulates the activity of GLP-1 and polypeptide YY (PYY) which regulate appetite and motility. No data are yet available on the tissue and plasma expression of DP4 in inflammatory bowel disease (IBD). METHODS Tissue and plasma were studied from active CD and healthy controls for DP4 quantification. Experiments were also carried out in a reductionist Caco-2 cell line model of intestinal inflammation with TNFα incubation. DP4 expression was studied by tissue Western blotting and plasma enzymelinked immunosorbent assay (ELISA), in addition to quantitative polymerase chain reaction (qPCR). RESULTS There was a ~2.7-fold decrease in DP4 protein in CD tissue (p=0.05). Plasma DP4 in CD was also significantly lower than the control group. A negative correlation between plasma DP4 levels and inflammatory activity as measured by C-reactive protein was observed. In Caco-2 cells an ~18-fold increase (p<0.0001) in DP4 protein expression was seen after incubation with TNFα at a concentration of 25 ng/μl for 48 hours paralleled by a 2-fold increase in DP4 mRNA. DISCUSSION DP4 is reduced in tissue and plasma in active Crohn's disease. This is unlikely to represent simple downregulation induced by inflammation since the key proinflammatory cytokine strongly upregulated DP4 expression in Caco-2 cells. Clearly a more complex situation exists in vivo. We propose that reduced DP4 activity limits the cleavage of regulatory peptides, for example potentiating the trophic signal from GLP-2. Pharmacological DP4 inhibition may present an additional therapeutic target in IBD.
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Affiliation(s)
- G W Moran
- Inflammation Sciences Research Group, Manchester Academic Health Science Centre, University of Manchester, Manchester, M13 9PL, UK
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Brubaker PL, Drucker DJ. Structure-Function of the Glucagon Receptor Family of G Protein-Coupled Receptors: The Glucagon, GIP, GLP-1, and GLP-2 Receptors. ACTA ACUST UNITED AC 2011. [DOI: 10.3109/10606820213687] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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Shi X, Li X, Wang Y, Zhang K, Zhou F, Chan L, Li D, Guan X. Glucagon-like peptide-2-stimulated protein synthesis through the PI 3-kinase-dependent Akt-mTOR signaling pathway. Am J Physiol Endocrinol Metab 2011; 300:E554-63. [PMID: 21177288 PMCID: PMC3279303 DOI: 10.1152/ajpendo.00620.2010] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Glucagon-like peptide-2 (GLP-2) is a nutrient-responsive neuropeptide that exerts diverse actions in the gastrointestinal tract, including enhancing mucosal cell survival and proliferation. GLP-2 stimulates mucosal growth in vivo with an increased rate of protein synthesis. However, it was unclear whether GLP-2 can directly stimulate protein synthesis. The objective was to test critically whether GLP-2 receptor (GLP-2R) activation directly stimulates protein synthesis through a PI 3-kinase-dependent Akt-mTOR signaling pathway. HEK 293 cells (transfected with human GLP-2R cDNA) were treated with human GLP-2 with/without pretreatment of PI 3-kinase inhibitor (LY-294002) or mTOR inhibitor (rapamycin). Results show that 1) GLP-2 specifically bound to GLP-2R overexpressed in the HEK cells with K(a) = 0.22 nM and B(max) = 321 fmol/μg protein; 2) GLP-2-stimulated protein synthesis was dependent on the amount of GLP-2R cDNA and the dosage of GLP-2 and reached the plateau among 0.2-2 nM GLP-2; 3) GLP-2-stimulated protein synthesis was abolished by the PI 3-kinase inhibitor and mTOR inhibitor; and 4) GLP-2-mediated stimulation of phosphorylation on Akt and mTOR was dependent on the amount of GLP-2R cDNA transfected and the dosage of GLP-2. In addition, GLP-2-mediated action and signaling in regulation of protein synthesis were confirmed in mouse hippocampal neurons (expressing native GLP-2R). GLP-2 directly stimulated protein synthesis of primary cultured neurons in dosage-dependent, PI 3-kinase-dependent, and rapamycin-sensitive manners, which linked with activation of Akt-mTOR signaling pathway as well. We conclude that GLP-2R activation directly stimulates protein synthesis by activating the PI 3-kinase-dependent Akt-mTOR signaling pathway. GLP-2-stimulated protein synthesis may be physiologically relevant to maintaining neuronal long-term potentiation and providing secondary mediators (namely neuropeptides or growth factors).
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Affiliation(s)
- Xuemei Shi
- USDA/ARS Children's Nutrition Research Center, Dept. of Pediatrics, Baylor College of Medicine, 1100 Bates St., Houston, TX 77030, USA
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Enteric nervous system in the small intestine: pathophysiology and clinical implications. Curr Gastroenterol Rep 2011; 12:358-65. [PMID: 20725870 DOI: 10.1007/s11894-010-0129-9] [Citation(s) in RCA: 98] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
The digestive system is endowed with its own, local nervous system, referred to as the enteric nervous system (ENS). Given the varied functions of small intestine, its ENS has developed individualized characteristics relating to motility, secretion, digestion, and inflammation. The ENS regulates the major enteric processes such as immune response, detecting nutrients, motility, microvascular circulation, intestinal barrier function, and epithelial secretion of fluids, ions, and bioactive peptides. Remarkable progress has been made in understanding the signaling pathways in this complex system and how they work. In this article, we focus on recent advances that have led to new insights into small intestinal ENS function and the development of new therapies.
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The role of glucagon-like peptide-2 on apoptosis, cell proliferation, and oxidant-antioxidant system at a mouse model of intestinal injury induced by tumor necrosis factor-alpha/actinomycin D. Mol Cell Biochem 2010; 350:13-27. [PMID: 21153865 DOI: 10.1007/s11010-010-0678-0] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2010] [Accepted: 12/02/2010] [Indexed: 12/18/2022]
Abstract
Tumor necrosis factor-alpha (TNF-α) is a multifunctional cytokine, which has the ability to produce cytotoxicity via induction of cell death and cell cycle arrest. Blocking the synthesis of protective proteins through a transcriptional inhibitor such as actinomycin D (Act D) sensitizes many cell types to TNF-α toxicity. Teduglutide, h[Gly(2)]GLP-2, is a protease-resistant synthetic analog of glucagon-like peptide-2 (GLP-2) which is an intestinotrophic peptide. In this study, we evaluated this potential of GLP-2 on apoptosis, cell proliferation, and oxidant-antioxidant system on a mouse model of intestinal injury induced by TNF-α/Act D. The intestinal injury was induced by intraperitoneal administration of 15 μg/kg TNF-α and 800 μg/kg Act D per mouse. Animals were injected subcutaneously 200 μg/kg h[Gly(2)]GLP-2 every 12 h for 10 consecutive days prior to the administration of TNF-α and Act D. The model of intestinal injury induced by TNF-α/Act D, which is the new animal model for the intestinal disorders, was characterized by the degeneration of intestinal mucosa, an increase in apoptotic index, expression of active caspase-3, lipid peroxidation and glutathione (GSH) levels, glutathione peroxidase (GPx) and superoxide dismutase (SOD) activities; a decrease in cell proliferation and catalase (CAT) activity. h[Gly(2)]GLP-2 pretreatment prevented the TNF-α/Act D-induced oxidative injury by a significant reduction in the intestinal injury, apoptotic index, expression of active caspase-3, lipid peroxidation and GSH levels, GPx and SOD activities; a markedly increase in cell proliferation, and CAT activity. These results demonstrate that GLP-2 has a protective, antiapoptotic, proliferative, and antioxidant effects against to TNF-α/Act D-induced intestinal injury. It is suggested that GLP-2 may potentially be useful as a therapeutic agent in TNF-α-mediated intestinal disorders.
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Can we protect the gut in critical illness? The role of growth factors and other novel approaches. Crit Care Clin 2010; 26:549-65, x. [PMID: 20643306 DOI: 10.1016/j.ccc.2010.04.005] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
The intestine plays a central role in the pathophysiology of critical illness and is frequently called the "motor" of the systemic inflammatory response. Perturbations to the intestinal barrier can lead to distant organ damage and multiple organ failure. Therefore, identifying ways to preserve intestinal integrity may be of paramount importance. Growth factors and other peptides have emerged as potential tools for modulation of intestinal inflammation and repair due to their roles in cellular proliferation, differentiation, migration, and survival. This review examines the involvement of growth factors and other peptides in intestinal epithelial repair during critical illness and their potential use as therapeutic targets.
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Yazbeck R, Sulda ML, Howarth GS, Bleich A, Raber K, von Hörsten S, Holst JJ, Abbott CA. Dipeptidyl peptidase expression during experimental colitis in mice. Inflamm Bowel Dis 2010; 16:1340-51. [PMID: 20186930 DOI: 10.1002/ibd.21241] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
BACKGROUND We have previously demonstrated that inhibition of dipeptidyl peptidase (DP) activity partially attenuates dextran sulfate sodium (DSS) colitis in mice. The aim of this study was to further investigate the mechanisms of this protection. MATERIALS AND METHODS Wildtype (WT) and DPIV(-/-) mice consumed 2% DSS in drinking water for 6 days to induce colitis. Mice were treated with saline or the DP inhibitors Ile-Pyrr-(2-CN)*TFA or Ile-Thia. DP mRNA and enzyme levels were measured in the colon. Glucagon-like peptide (GLP)-2 and GLP-1 concentrations were determined by radioimmunoassay, regulatory T-cells (Tregs) by fluorescence activated cell sorting (FACS) on FOXp3+T cells in blood, and neutrophil infiltration assessed by myeloperoxidase (MPO) assay. RESULTS DP8 and DP2 mRNA levels were increased (P < 0.05) in WT+saline mice compared to untreated WT mice with colitis. Cytoplasmic DP enzyme activity was increased (P < 0.05) in DPIV(-/-) mice at day 6 of DSS, while DP2 activity was increased (P < 0.05) in WT mice with colitis. GLP-1 (63%) and GLP-2 (50%) concentrations increased in WT+Ile-Pyrr-(2-CN)*TFA mice compared to day-0 controls. MPO activity was lower in WT+Ile-Thia and WT+Ile-Pyrr-(2-CN)*TFA treated mice compared to WT+saline (P < 0.001) at day 6 colitis. CONCLUSIONS DP expression and activity are differentially regulated during DSS colitis, suggesting a pathophysiological role for these enzymes in human inflammatory bowel disease (IBD). DP inhibitors impaired neutrophil recruitment and maintenance of the Treg population during DSS-colitis, providing further preclinical evidence for the potential therapeutic use of these inhibitors in IBD. Finally, DPIV appears to play a critical role in mediating the protective effect of DP inhibitors.
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Affiliation(s)
- Roger Yazbeck
- School of Biological Sciences, Flinders University, Adelaide, South Australia, Australia
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Buchman AL, Katz S, Fang JC, Bernstein CN, Abou-Assi SG. Teduglutide, a novel mucosally active analog of glucagon-like peptide-2 (GLP-2) for the treatment of moderate to severe Crohn's disease. Inflamm Bowel Dis 2010; 16:962-73. [PMID: 19821509 DOI: 10.1002/ibd.21117] [Citation(s) in RCA: 95] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
BACKGROUND Teduglutide, an analog of glucagon-like peptide-2 (GLP-2), is associated with trophic effects on gut mucosa. Its role in the treatment of active Crohn's disease (CD) was assessed in a pilot, randomized, placebo-controlled, double-blinded, dose-ranging study. METHODS Subjects with moderate-to-severe CD were randomized 1:1:1:1 to placebo or 1 of 3 doses of teduglutide (0.05, 0.10, or 0.20 mg/kg daily) delivered as a daily subcutaneous injection for 8 weeks. The primary outcome measure was the percentage of subjects in each group that responded to treatment, defined as a decrease in Crohn's Disease Activity Index (CDAI) score to <150 or a decrease of > 100 points. At week 8 there was an optional 12-week open-label period of treatment with teduglutide 0.10 mg/kg/d. RESULTS One hundred subjects were enrolled and 71 completed the study. The mean baseline CDAI score was 290.8 +/- 57.6 and was similar across groups. There were numerically higher response and remission rates in all teduglutide-treated groups as compared with placebo, although the percentage of subjects who achieved a clinical response or remission was more substantial, and seen as early as week 2 of treatment in the highest dose (0.2 mg/kg/d) group (44% response and 32% remission versus 32% response and 20% remission in the placebo group). Of subjects who had not achieved remission during the 8-week placebo-controlled phase in the higher-dose group, 50% achieved remission during the more prolonged, open-label treatment phase. Plasma citrulline was similar across groups at baseline, but increased substantially over time in all teduglutide groups when compared with placebo at week 8. Adverse events were not different between placebo and active treatment groups. CONCLUSIONS Teduglutide is a novel and potentially effective therapy for inducing remission and mucosal healing in patients with active moderate-to-severe CD. Further clinical investigation of this growth factor is warranted.
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Affiliation(s)
- Alan L Buchman
- Division of Gastroenterology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois 60611, USA.
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Yazbeck R, Howarth GS, Abbott CA. Growth factor based therapies and intestinal disease: is glucagon-like peptide-2 the new way forward? Cytokine Growth Factor Rev 2009; 20:175-84. [PMID: 19324585 DOI: 10.1016/j.cytogfr.2009.02.008] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Inflammatory bowel disease (IBD) is a chronic, debilitating disease associated with severe damage to the intestinal mucosa. Glucagon-like peptide-2 (GLP-2) is a potent and specific gastrointestinal growth factor that is demonstrating therapeutic potential for the prevention or treatment of an expanding number of intestinal diseases, including short bowel syndrome (SBS), small bowel enteritis and IBD. The biological activity of GLP-2 is limited due to proteolytic inactivation by the protease dipeptidyl peptidase (DP)IV. Inhibitors of DPIV activity may represent a novel strategy to prolong the growth promoting actions of GLP-2. This review outlines evidence for the clinical application of GLP-2, its degradation resistant analogue, Teduglutide, and novel DPIV inhibitors in efficacy studies utilizing pre-clinical models of intestinal damage, in particular IBD.
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Affiliation(s)
- Roger Yazbeck
- School of Biological Sciences, Flinders University, Adelaide, South Australia, Australia.
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Zhang W, Zhu W, Zhang J, Li N, Li J. Protective effects of glucagon-like peptide 2 on intestinal ischemia-reperfusion rats. Microsurgery 2008; 28:285-90. [DOI: 10.1002/micr.20491] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Wallis K, Walters JRF, Forbes A. Review article: glucagon-like peptide 2--current applications and future directions. Aliment Pharmacol Ther 2007; 25:365-72. [PMID: 17217448 DOI: 10.1111/j.1365-2036.2006.03193.x] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
BACKGROUND Glucagon-like peptide 2 (GLP-2) is an important peptide growth factor secreted from the human intestine. The trophic properties of GLP-2 are very specific to the gut where it is pivotal in the regulation of mucosal morphology, function and integrity. AIMS This review details the current understanding of the molecular biology of GLP-2, its mechanisms of action and physiological properties. A major focus is the discussion of recent clinical data evaluating the use of GLP-2 as a therapeutic agent. METHODS Relevant articles were identified using Medline searches and from the reference lists of key papers. RESULTS AND CONCLUSIONS In the treatment of short bowel syndrome, GLP-2 has been shown to be highly effective in improving fluid absorption. In Crohn's disease, GLP-2 is superior to placebo in the induction of remission. Early data also suggest that the effects of GLP-2 on bone metabolism can provide a new treatment approach for patients with osteoporosis. In the future, the positive effects of GLP-2 on intestinal barrier function, splanchnic perfusion and mucosal healing could be utilized to expand its therapeutic application to other causes of intestinal injury. However, important safety aspects need to be considered when using this potent growth-promoting agent for a long term.
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Affiliation(s)
- K Wallis
- Division of Medicine, Imperial College, Hammersmith Hospital, London, UK
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Deniz M, Bozkurt A, Kurtel H. Mediators of glucagon-like peptide 2-induced blood flow: responses in different vascular sites. ACTA ACUST UNITED AC 2007; 142:7-15. [PMID: 17346812 DOI: 10.1016/j.regpep.2007.01.002] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2006] [Revised: 01/05/2007] [Accepted: 01/07/2007] [Indexed: 11/19/2022]
Abstract
The aims of the present study were: to characterize the mechanisms of hemodynamic alterations induced by GLP-2, and, to compare the responses elicited in the superior mesenteric artery (SMA) to other vascular beds. Anesthetized rats were infused at the doses of 0.9, 2.3, 4.6 and 9.3 nmol/kg into the jugular vein for 60 min. Blood flow in the various arteries was measured by the ultrasonic transit time technique. Some animals were pretreated with indomethacin (5 mg/kg, ip), L-NAME (9, 18, 36 and 72 micromol/kg, iv), atropine sulfate (1-2 mg/kg, iv), CCK-1 and CCK-2 receptor antagonists (L-364,718 and L-365,260, 1 mg/kg, iv), exendin (9-39) amide (35 nmol/kg, iv) and lidocaine (74 micromol/kg, iv) prior to the infusion of GLP-2 (4.6 nmol/kg). In another group, capsaicin was applied either systematically (125 mg/kg, sc) or vagally (1 mg/rat). GLP-2 administration at all doses significantly increased the SMA blood flow throughout the experiments. GLP-2 (4.6 nmol/kg) infusion significantly increased blood flow of inferior mesenteric artery and carotid artery but not in any other vessel measured. Only the pretreatments with L-NAME and lidocaine were ineffective in preventing the GLP-2-induced responses. These results implicate that GLP-2-induced blood flow alterations are most significant in the SMA and are not mediated by prostaglandins, muscarinic, GLP-1 or CCK receptors. Our results also suggest that the stimulatory effect of GLP-2 on SMA blood flow is NO-dependent and mediated via intrinsic, non-cholinergic enteric neurons.
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Affiliation(s)
- Mustafa Deniz
- Marmara University School of Medicine, Department of Physiology, 34668 Haydarpaşa, Istanbul, Turkey.
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