|
1
|
Cheng Q, Feng X, Meng Q, Li Y, Chen S, Wang G, Nie K. [6]-Gingerol Ameliorates Cisplatin-Induced Pica by Regulating the TPH/MAO-A/SERT/5-HT/5-HT 3 Receptor System in Rats. Drug Des Devel Ther 2020; 14:4085-4099. [PMID: 33061309 PMCID: PMC7538004 DOI: 10.2147/dddt.s270185] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2020] [Accepted: 09/01/2020] [Indexed: 11/23/2022] Open
Abstract
PURPOSE [6]-gingerol is a bioactive compound extracted from ginger, a traditional anti-emetic herb in Chinese medicine. Previous studies have demonstrated that [6]-gingerol can ameliorate chemotherapy-induced pica in rats, although the underlying mechanism has not been elucidated. This study is designed to investigate [6]-gingerol's antiemetic mechanism focusing on the 5-hydroxytryptamine (serotonin, 5-HT) system by evaluating the synthesis, metabolism and reuptake of 5-HT, as well as the mechanism of 5-hydroxytryptamine type 3 receptor (5-HT3 receptor), in a cisplatin-induced pica model of rats. METHODS Rats were randomly divided into control group (vehicle + saline, Con), [6]-gingerol control group (50 mg/kg [6]-gingerol + saline, G-con), ondansetron control group (2.6 mg/kg ondansetron + saline, O-con), cisplatin model group (vehicle + cisplatin, Model), ondansetron-treated group (2.6 mg/kg ondansetron + cisplatin, O-treated), high dosage of [6]-gingerol-treated group (100 mg/kg [6]-gingerol + cisplatin, GH-treated), and low dosage of [6]-gingerol-treated group (50 mg/kg [6]-gingerol + cisplatin, GL-treated). The rats were administered with [6]-gingerol, ondansetron, and vehicle (3% Tween-80) by gavage twice (7:00 AM and 7:00 PM). One hour after the first treatment (8:00 AM), rats in groups Model, O-treated, GH-treated and GL-treated were injected intraperitoneally (i.p.) with 6 mg/kg cisplatin, and the other groups were injected i.p. with saline of equal volume. The consumption of kaolin of the rats were measured. All the rats were anesthetized by i.p. injection of pentobarbital sodium at 24 h post-cisplatin. After blood samples were taken, medulla oblongata and ileum were removed. The levels of 5-HT and its metabolite 5-HIAA in ileum, medulla oblongata and serum were determined using high-performance liquid chromatography with electrochemical detection (HPLC-ECD). The mRNA expression levels of 5-HT3 receptor, tryptophan hydroxylase (TPH), monoamine oxidase A (MAO-A) and serotonin reuptake transporter (SERT) were detected by real-time PCR. The protein expression levels and distribution of 5-HT3 receptor, TPH and MAO-A in the medulla oblongata and ileum were measured by Western blotting and immunohistochemistry, respectively. RESULTS [6]-gingerol treatment significantly reduced the kaolin ingestion and the increase in 5-HT concentration in rats induced by cisplatin. TPH, MAO-A, SERT, and 5-HT3 receptor are important in 5-HT metabolism, and cisplatin-induced alterations in the associated protein/mRNA levels were restored when treated with [6]-gingerol. CONCLUSION This suggests that the antiemetic effect of [6]-gingerol against cisplatin-induced emesis may be due to 5-HT attenuation via modulating the TPH/MAO-A/SERT/5-HT/5-HT3 receptor system.
Collapse
MESH Headings
- Animals
- Antiemetics/administration & dosage
- Antiemetics/chemistry
- Antiemetics/pharmacology
- Catechols/administration & dosage
- Catechols/chemistry
- Catechols/pharmacology
- Cisplatin/administration & dosage
- Cisplatin/antagonists & inhibitors
- Fatty Alcohols/administration & dosage
- Fatty Alcohols/chemistry
- Fatty Alcohols/pharmacology
- Injections, Intraperitoneal
- Male
- Molecular Conformation
- Monoamine Oxidase/analysis
- Monoamine Oxidase/genetics
- Monoamine Oxidase/metabolism
- Pica/chemically induced
- Pica/drug therapy
- Pica/metabolism
- RNA, Messenger/analysis
- RNA, Messenger/genetics
- RNA, Messenger/metabolism
- Rats
- Rats, Sprague-Dawley
- Receptors, Serotonin/analysis
- Receptors, Serotonin/genetics
- Receptors, Serotonin/metabolism
- Receptors, Serotonin, 5-HT3/analysis
- Receptors, Serotonin, 5-HT3/genetics
- Receptors, Serotonin, 5-HT3/metabolism
- Tryptophan Hydroxylase/analysis
- Tryptophan Hydroxylase/genetics
- Tryptophan Hydroxylase/metabolism
Collapse
Affiliation(s)
- Qianqian Cheng
- School of Chinese Materia Medica, Guangdong Pharmaceutical University, Guangzhou, Guangdong Province 510006, People's Republic of China
| | - Xiaodi Feng
- School of Chinese Materia Medica, Guangdong Pharmaceutical University, Guangzhou, Guangdong Province 510006, People's Republic of China
| | - Qi Meng
- School of Chinese Materia Medica, Guangdong Pharmaceutical University, Guangzhou, Guangdong Province 510006, People's Republic of China
- School of Chinese Medicine, Shandong University of Traditional Chinese Medicine, Jinan, Shandong Province 250355, People's Republic of China
| | - Yaqi Li
- School of Chinese Materia Medica, Guangdong Pharmaceutical University, Guangzhou, Guangdong Province 510006, People's Republic of China
| | - Siqi Chen
- School of Chinese Materia Medica, Guangdong Pharmaceutical University, Guangzhou, Guangdong Province 510006, People's Republic of China
| | - Guoen Wang
- School of Chinese Materia Medica, Guangdong Pharmaceutical University, Guangzhou, Guangdong Province 510006, People's Republic of China
| | - Ke Nie
- School of Chinese Materia Medica, Guangdong Pharmaceutical University, Guangzhou, Guangdong Province 510006, People's Republic of China
| |
Collapse
|
|
2
|
Decker AM, Blough BE. Development of serotonin transporter reuptake inhibition assays using JAR cells. J Pharmacol Toxicol Methods 2018; 92:52-56. [PMID: 29555537 DOI: 10.1016/j.vascn.2018.03.003] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2017] [Revised: 02/13/2018] [Accepted: 03/14/2018] [Indexed: 11/17/2022]
Abstract
INTRODUCTION The development and validation of serotonin transporter reuptake inhibition assays in 96-well format using commercially available human placental choriocarcinoma JAR cells is described. METHODS JAR cells were first shown to uptake [3H]serotonin in a saturable fashion with a KM value of 1 μM as determined by a Michaelis-Menten kinetic analysis. The cells were then utilized to determine the reuptake inhibition potencies of known ligands and the results were compared with results previously generated in the two most commonly used transporter assays (rat brain synaptosomes and transfected HEK293 cells). RESULTS Examination of a variety of ligands including selective serotonin reuptake inhibitors, tricyclic antidepressants, piperazine derivatives, and phenyltropane derivatives demonstrated that JAR cells are capable of detecting reuptake inhibition activity of a variety of ligands with potencies that correlate with one or both of the other assays. DISCUSSION This study demonstrates a novel pharmacological method of assessing human serotonin transporter reuptake inhibition activity using commercially available JAR cells. Our results show that JAR cells provide an easily available and good alternative to using rat brain tissue and HEK293 cells, with the advantage of studying serotonin transporter reuptake inhibition in a human background.
Collapse
Affiliation(s)
- Ann M Decker
- Center for Drug Discovery, RTI International, Research Triangle Park, NC 27709, USA.
| | - Bruce E Blough
- Center for Drug Discovery, RTI International, Research Triangle Park, NC 27709, USA.
| |
Collapse
|
|
3
|
Electroacupuncture Restores 5-HT System Deficit in Chronic Mild Stress-Induced Depressed Rats. EVIDENCE-BASED COMPLEMENTARY AND ALTERNATIVE MEDICINE 2016; 2016:7950635. [PMID: 27994633 PMCID: PMC5141535 DOI: 10.1155/2016/7950635] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/01/2016] [Revised: 08/21/2016] [Accepted: 09/14/2016] [Indexed: 01/08/2023]
Abstract
Objective. The current study is designed to investigate the antidepressant efficacy of electroacupuncture (EA) treatment by evaluating its effect on the synthesis, metabolism, reuptake, and receptors of 5-hydroxytryptamine (5-HT), so as to clarify the molecular mechanisms of EA for antidepression. Materials and Methods. Solitary combined with the chronic unpredictable mild stress (CUMS) was used to establish the rat model with depression. The depressed rats were supplied with EA treatment for 4 weeks, and the behavior change and the following indices including 5-HT, 5-hydroxyindoleacetic acid (5-HIAA), monoamine oxidase A (MAO-A), tryptophan hydroxylase (TPH), 5-HT transporter (SERT), 5-HT1A, and 5-HT2A in hippocampus and prefrontal cortex were examined. Results. EA treatment significantly improved the behavior of rats and increased 5-HT level in hippocampus of depressed rats. Similarly, EA treatment could significantly increase protein and mRNA expression of TPH and 5-HT1A during 5-HT synthesis process in hippocampus of depressed rats. However, EA treatment had no effect on the activity of MAO-A and the expression of SERT protein and mRNA. Conclusion. Antidepressant efficacy of EA treatment can be accomplished through enhancing 5-HT synthesis, upregulating 5-HT1A level, and improving 5-HT content in brain and synaptic gaps.
Collapse
|
|
4
|
Manzetti S, Zhang J, van der Spoel D. Thiamin Function, Metabolism, Uptake, and Transport. Biochemistry 2014; 53:821-35. [DOI: 10.1021/bi401618y] [Citation(s) in RCA: 195] [Impact Index Per Article: 17.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Affiliation(s)
- Sergio Manzetti
- Uppsala
Center for Computational Chemistry, Science for Life Laboratory, Department
for Cell and Molecular Biology, University of Uppsala, Box 596, 751
24 Uppsala, Sweden
- Fjordforsk A.S., Fresvik 6896, Norway
| | - Jin Zhang
- Uppsala
Center for Computational Chemistry, Science for Life Laboratory, Department
for Cell and Molecular Biology, University of Uppsala, Box 596, 751
24 Uppsala, Sweden
- Department
of Chemistry, Zhejiang University, Hangzhou 310027, China
| | - David van der Spoel
- Uppsala
Center for Computational Chemistry, Science for Life Laboratory, Department
for Cell and Molecular Biology, University of Uppsala, Box 596, 751
24 Uppsala, Sweden
| |
Collapse
|
|
5
|
Rong JM, Ji HZ, Wu XW, Sun Q, Guo MX, Xu XB, Wang FY. Increased expression of chymase in inflammatory polyps in elderly patients with functional bowel disorder. Exp Ther Med 2014; 7:371-374. [PMID: 24396407 PMCID: PMC3881056 DOI: 10.3892/etm.2013.1444] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2013] [Accepted: 10/18/2013] [Indexed: 12/05/2022] Open
Abstract
Chymase, a chymotrypsin-like protease, is a non-angiotensin-converting enzyme (ACE) angiotensin II (Ang II)-generating enzyme. The aim of the present study was to investigate whether chymase activity was increased in inflammatory polyps of elderly patients with functional bowel disorder (FBD). This study enrolled 45 elderly patients with FBD and 44 healthy control individuals. Expression of chymase in intestinal mucosa was assessed using fluorescence quantitative polymerase chain reaction and immunohistochemistry (IHC). IHC showed an increased number of chymase-positive mast cells in inflammatory polyps than in healthy intestinal mucosa (P<0.05). Compared with healthy mucosa, expression of chymase at the mRNA and protein level was significantly higher in inflammatory polyps. The frequencies of the chymase GG genotype and the G allele type were higher in the intestinal mucosa of patients with FBD compared with healthy controls (66.67 versus 40.91%, 81.11 versus 63.63%, both P<0.05). The frequency of the G allele type in the intestinal mucosa of the C4 subgroup of FBD was higher than that in the control group. However, in other FBD subgroups, there was no difference between patients and controls. Based on the fact that enhanced chymase expression was observed in inflammatory polyps of elderly patients with FBD relative to those in healthy controls, it was concluded that chymase has a significant role in the pathogenesis of inflammatory polyps in elderly patients with FBD.
Collapse
Affiliation(s)
- Jian-Ming Rong
- Department of Geratology, No.454 Hospital of PLA, Nanjing, Jiangsu 210002, P.R. China
| | - Hong-Zan Ji
- Department of Gastroenterology, Nanjing Jin Ling Hospital, Nanjing, Jiangsu 210002, P.R. China
| | - Xiao-Wei Wu
- Department of Gastroenterology, Nanjing Jin Ling Hospital, Nanjing, Jiangsu 210002, P.R. China
| | - Quan Sun
- Department of Gastroenterology, Nanjing Jin Ling Hospital, Nanjing, Jiangsu 210002, P.R. China
| | - Mei-Xia Guo
- Department of Gastroenterology, Nanjing Jin Ling Hospital, Nanjing, Jiangsu 210002, P.R. China
| | - Xiao-Bing Xu
- Department of Gastroenterology, Nanjing Jin Ling Hospital, Nanjing, Jiangsu 210002, P.R. China
| | - Fang-Yu Wang
- Department of Gastroenterology, Nanjing Jin Ling Hospital, Nanjing, Jiangsu 210002, P.R. China
| |
Collapse
|
|
6
|
Dong XZ, Li ZL, Zheng XL, Mu LH, Zhang GQ, Liu P. A representative prescription for emotional disease, Ding-Zhi-Xiao-Wan restores 5-HT system deficit through interfering the synthesis and transshipment in chronic mild stress-induced depressive rats. JOURNAL OF ETHNOPHARMACOLOGY 2013; 150:1053-1061. [PMID: 24184266 DOI: 10.1016/j.jep.2013.10.018] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/20/2013] [Revised: 08/06/2013] [Accepted: 10/07/2013] [Indexed: 06/02/2023]
Abstract
ETHNOPHARMACOLOGICAL RELEVANCE Ding-Zhi-Xiao-Wan (DZ, also known as Kai-Xin-San) is a famous traditional Chinese medicine used for the treatment of emotional disease. Previously, we have found that in a variety of animal models of depression (such as tail suspension model, model of chronic fatigue and forced swimming model) DZ demonstrated significant antidepressant behavior and promoted the production of 5-hydroxytryptamine (5-HT). However, the mechanisms of 5-HT regulation are still unclear. Therefore, the current study is designed to further investigate the antidepressant effect of DZ by observing its influence on 5-HT synthesis, metabolism, transport and other key links, so as to clarify the molecular mechanism of its 5-HT regulation. MATERIALS AND METHODS Solitary rising combined with the chronic unpredictable mild stress (CMS) was used to establish the rat model of depression. The rats were given DZ for 3 weeks, the behavior change and the following items in hippocampus and prefrontal cortex were detected simultaneously: 5-HT, 5-hydroxyindoleacetic acid (5-HIAA), tryptophan hydroxylase (TPH), aromatic amino acid decarboxylase (AADC), monoamine oxidase (MAO) and 5-HT transporter (5-HTT) were observed. RESULTS Our results showed that treatment with the DZ significantly improved the behavior and simultaneously increased the 5-HT level in the hippocampus, prefrontal cortex tissues and hippocampus extracellular of depressive rats. In future studies revealed that DZ could significantly increase the protein and mRNA expression of the key enzymes TPH during the 5-HT synthesis process in the hippocampus and prefrontal cortex of the depressed rats, and suppress the expression of 5-HTT protein and mRNA at the same time. But it had no effects on MAO-A and MAO-B activities. CONCLUSION We believe that antidepressant effect of DZ is caused by the increase of 5-HT synthesis and reduction of 5-HT re-uptake, and eventually increase the content of 5-HT in the brain and the synaptic gaps.
Collapse
Affiliation(s)
- Xian-Zhe Dong
- Department of Clinical Pharmacology, General Hospital of Chinese PLA, 28# Fuxing Road, Haidian District, Beijing 100853, China
| | | | | | | | | | | |
Collapse
|
|
7
|
Yu XZ, Liu HF, Sun ZX. Investigation of the effect of military stress on the prevalence of functional bowel disorders. World J Gastroenterol 2012; 18:3004-7. [PMID: 22736925 PMCID: PMC3380329 DOI: 10.3748/wjg.v18.i23.3004] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/21/2011] [Revised: 03/01/2012] [Accepted: 04/02/2012] [Indexed: 02/06/2023] Open
Abstract
AIM: To investigate the morbidity of functional bowel disorders (FBD) under military stress conditions in order to lay foundations for the prevention and treatment of this disease.
METHODS: Four hundred and fifty-seven soldiers who were assigned to specified services and 471 soldiers who were assigned to routine services were enrolled using cluster sampling, with the latter as a control group. They were surveyed using the Rome III FBD standard questionnaire. The FBD symptom questionnaire included FBD-related symptoms, severity, duration or attack time, and accompanying symptoms.
RESULTS: The morbidity of the military stress group (14.6%) was significantly higher than in the control group (9.98%) (χ2 = 4.585, P < 0.05). The incidence of smoking, abdominal pain and acid regurgitation (χ2 = 4.761, P < 0.05) as well as the ZUNG anxiety/depression scores (χ2 = 7.982, P < 0.01) were also significantly higher in the military stress group compared with the control group. ZUNG anxiety (χ2 = 11.523, P < 0.01) and depression (χ2 = 5.149, P < 0.05) scores were higher in the FBD group compared with the non-FBD group. The differences in the ZUNG self-rated anxiety and depression scales between the 2 groups were statistically significant (χ2 = 14.482, P < 0.01 and χ2 = 6.176, P < 0.05).
CONCLUSION: The morbidity of FBD was higher under military stress conditions.
Collapse
|
|
8
|
Lemos C, Faria A, Meireles M, Martel F, Monteiro R, Calhau C. Thiamine is a substrate of organic cation transporters in Caco-2 cells. Eur J Pharmacol 2012; 682:37-42. [PMID: 22387857 DOI: 10.1016/j.ejphar.2012.02.028] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2011] [Revised: 02/07/2012] [Accepted: 02/15/2012] [Indexed: 01/11/2023]
Abstract
The aim of this study was to characterize the intestinal absorption of thiamine, by investigating the hypothesis of an involvement of Organic Cation Transporter (OCT) family members in this process. [(3)H]-T(+) uptake was found to be: 1) time-dependent, 2) Na(+)- and Cl(-)-dependent, 3) pH-dependent, with uptake increasing with a decrease in extracellular pH and decreasing with a decrease in intracellular pH, 4) inhibited by amiloride, 5) inhibited by the thiamine structural analogues oxythiamine and amprolium, 6) inhibited by the unrelated organic cations MPP(+), clonidine, dopamine, serotonin, 7) inhibited by the OCT inhibitors decynium22 and progesterone. Moreover, the dependence of [(3)H]-T(+) uptake on phosphorylation/dephosphorylation mechanisms was also investigated and [(3)H]-T(+) uptake was found to be reduced by PKA activation and protein tyrosine phosphatase and alkaline phosphatase inhibition. In conclusion, our results are compatible with the possibility of thiamine being transported not only by ThTr1 and/or ThTr2, but also by members of the OCT family of transporters (most probably OCT1 and/or OCT3), thus sharing the same transporters with several other organic cations at the small intestinal level.
Collapse
Affiliation(s)
- Clara Lemos
- Department of Biochemistry (U38-FCT), Faculty of Medicine, University of Porto, 4200-319 Porto, Portugal
| | | | | | | | | | | |
Collapse
|
|
9
|
Vasiliou SA, Ali FR, Haddley K, Cardoso MC, Bubb VJ, Quinn JP. The SLC6A4 VNTR genotype determines transcription factor binding and epigenetic variation of this gene in response to cocaine in vitro. Addict Biol 2012; 17:156-70. [PMID: 21309950 DOI: 10.1111/j.1369-1600.2010.00288.x] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
We demonstrated that the genotype of the variable number tandem repeats (VNTRs) in the linked polymorphic region (LPR) of the 5' promoter and in the intron 2 (Stin2) transcriptional regulatory domains of the serotonin transporter SLC6A4 gene determined its promoter interactions with transcription factors and co-activators in response to cocaine in the JAr cell line. The LPR variants contain 14 (short, s) or 16 (long, l) copies of a 22-23 bp repeat element, whereas the Stin2 VNTR exists as three variants containing 9, 10 or 12 copies of a 16-17 bp repeat. We observed a differential effect of cocaine on the association of the promoter with the transcription factor CTCF, which bound to both LPR alleles prior to cocaine exposure but only to the l-allele following exposure. Significantly, this differential effect of cocaine was correlated with the binding of the transcriptional regulator MeCP2 specifically to the s-allele and recruiting the histone deacetylase complex (HDAC). Concurrently, cocaine increased the association of positive histone marks over the SLC6A4 gene locus. At the Stin2 domain, we lost binding of the transcription factor YB-1, while CTCF remained bound. Our biochemical data are consistent with differential reporter gene activity directed by the individual or dual domains in response to cocaine in an Epstein-Barr virus-based episome model of stable transfections. These observations suggest that exposure of JAr cells to cocaine may result in differential binding of transcription factors and activators based on a specific genotype that might alter epigenetic parameters affecting gene expression after the initial challenge.
Collapse
|
|
10
|
Ki HA, Naoghare PK, Oh BK, Choi JW, Song JM. Nondestructive quantum dot-based intracellular serotonin imaging in intact cells. Anal Biochem 2009; 388:23-7. [DOI: 10.1016/j.ab.2009.01.041] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2008] [Revised: 01/19/2009] [Accepted: 01/28/2009] [Indexed: 10/21/2022]
|
|
11
|
Fischer W, Metzner L, Hoffmann K, Neubert RHH, Brandsch M. Substrate specificity and mechanism of the intestinal clonidine uptake by Caco-2 cells. Pharm Res 2006; 23:131-7. [PMID: 16333714 DOI: 10.1007/s11095-005-8925-x] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2005] [Accepted: 10/03/2005] [Indexed: 10/25/2022]
Abstract
PURPOSE This study was performed to characterize the substrate specificity and mechanism of the intestinal clonidine transport. METHODS Uptake of [3H]clonidine into Caco-2 cells was investigated. Interaction with drugs was studied in competition assays. RESULTS Uptake of [3H]clonidine was linear for up to 2 min, Na+-independent, and insensitive to changes in membrane potential, but strongly H+-dependent. The uptake rate of clonidine was saturable with kinetic parameters of 0.5+/-0.1 mM (Kt) and 16.6+/-1.8 nmol/2 min per mg of protein (Vmax) at an outside pH of 7.5. Many drugs such as clonidine, guanabenz, methamphetamine, imipramine, clomipramine, nortriptyline, quinine, xylazine, ephedrine, and diphenhydramine strongly inhibited the [3H]clonidine uptake with Ki values between 0.15 and 1 mM. CONCLUSIONS Clonidine is transported by a carrier-mediated process. Substrate specificity and mechanism are very similar to the transport described in blood-brain barrier endothelial cells. The transport characteristics do not correspond to carriers for organic cations of the SLC22 family or the choline transporters CHT1 and CLT1. The system might be identical to the H+/tertiary amine antiporter. It interacts with a large number of both hydrophilic and lipophilic cationic drugs, and also, interestingly, with opiates.
Collapse
Affiliation(s)
- Wiebke Fischer
- Membrane Transport Group, Biozentrum, Martin Luther University Halle-Wittenberg, Weinbergweg 22, D-06120, Halle, Germany
| | | | | | | | | |
Collapse
|
|
12
|
Keating E, Lemos C, Azevedo I, Martel F. Characteristics of thiamine uptake by the BeWo human trophoblast cell line. BMB Rep 2006; 39:383-93. [PMID: 16889681 DOI: 10.5483/bmbrep.2006.39.4.383] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
Little is known concerning the mechanisms responsible for the transplacental transfer of thiamine. So, the aim of this work was to characterize the placental uptake of thiamine from the maternal circulation, by determining the characteristics of 3H-thiamine uptake by a human trophoblast cell line (BeWo). Uptake of (3)H-thiamine (50-100 nM) by BeWo cells was: 1) temperature-dependent and energy-independent; 2) pH-dependent (uptake increased as the extracellular medium pH decreased); 3) Na(+)-dependent and Cl(-)-independent; 4) not inhibited by the thiamine structural analogs amprolium, oxythiamine and thiamine pyrophosphate; 5) inhibited by the unrelated organic cations guanidine, N-methylnicotinamide, tetraethylammonium, clonidine and cimetidine; 6) inhibited by the organic cation serotonin, and by two selective inhibitors of the serotonin plasmalemmal transporter (hSERT), fluoxetine and desipramine. We conclude that (3)H-thiamine uptake by BeWo cells seems to occur through a process distinct from thiamine transporter-1 (hThTr-1) and thiamine transporter-2 (hThTr-2). Rather, it seems to involve hSERT. Moreover, chronic (48 h) exposure of cells to caffeine (1 microM) stimulated and chronic exposure to xanthohumol and iso-xanthohumol (1 and 0.1 microM, respectively) inhibited (3)H-thiamine uptake, these effects being not mediated through modulation of the expression levels of either hThTr-1 or hSERT mRNA.
Collapse
Affiliation(s)
- Elisa Keating
- Department of Biochemistry (U38-FCT), Faculty of Medicine, University of Porto, 4200-319 Porto, Portugal
| | | | | | | |
Collapse
|
|
13
|
Zhang XM, Lin ZH. Relationship between serotonin transporter gene polymorphism and irritable bowel syndrome. Shijie Huaren Xiaohua Zazhi 2006; 14:1790-1794. [DOI: 10.11569/wcjd.v14.i18.1790] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
AIM: To investigate the relationship between serotonin transporter gene polymorphism and irritable bowel syndrome (IBS).
METHODS: Polymerase chain reaction (PCR) was used to comparatively analyze the polymorphisms of serotonin transporter gene 5-HTTLPR and VNTRs within intron 2 in patients with diarrhea-predominant IBS (D-IBS, n = 51), constipation-predominant IBS (C-IBS, n = 58), and alternating diarrhea and constipation IBC (A-IBS, n = 38) and healthy controls (n = 48).
RESULTS: The frequencies of L/L genotype and L allele in C-IBS patients were significantly higher than those in the controls (31.0% vs 8.3%, χ2 = 8.229, P < 0.05; 47.4% vs 29.2%, χ2 = 7.342, P < 0.05). The frequencies of S/S genotype and S allele in D-IBS patients were significantly higher than those in C-IBS and A-IBS patients (S/S: 56.9% vs 36.2%, 36.8%, P < 0.05; S: 71.6% vs 52.6%, 56.6%, P < 0.05), but the frequency of L/L genotype was markedly lower (9.8% vs 31.0%, 23.7%, P < 0.05). However, no significant difference was found in VNTRs polymorphism between the subgroups of IBS and controls (P > 0.05).
CONCLUSION: The presence of L/L genotype and L allele probably increases the susceptibility of individuals to C-IBS, while S/S genotype and S allele probably increases that to D-IBS. L/L genotype may be a protective factor against D-IBS.
Collapse
|
|
14
|
Thomson AD, Marshall EJ. The natural history and pathophysiology of Wernicke's Encephalopathy and Korsakoff's Psychosis. Alcohol Alcohol 2005; 41:151-8. [PMID: 16384871 DOI: 10.1093/alcalc/agh249] [Citation(s) in RCA: 132] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
AIMS To identify the early clinical indications of thiamine deficiency and to understand the factors involved in the development of the amnesic state in alcohol-dependent individuals with thiamine deficiency. It is hoped that this will highlight the need for clinicians to treat alcohol-dependent patients prophylactically with parenteral thiamine and thus prevent the development of Korsakoff's Psychosis (KP). METHOD We have reviewed the natural history and pathophysiology of Wernicke's Encephalopathy (WE) in both human and animal studies together with any contributory factors that may predispose the individual to thiamine deficiency. A further understanding of these problems is provided by recent studies into the metabolic consequences of thiamine deficiency and alcohol misuse. CONCLUSIONS Where WE is due to thiamine deficiency alone (i.e. in the absence of alcohol misuse) KP rarely supervenes following thiamine replacement therapy. Successful treatment or prophylaxis of WE in alcohol dependence probably depends on a number of inter-related issues and is not simply a matter of early and adequate thiamine treatment. If sufficient alcohol-related neurotoxicity has occurred by the time of diagnosis, then this may be the more important or limiting factor with respect to the long-term outcome. This possible obstacle to complete recovery should not prevent every attempt being made to provide the patient with optimum brain thiamine replacement.
Collapse
Affiliation(s)
- Allan D Thomson
- Molecular Psychiatry Laboratory, Windeyer Institute of Medical Sciences, Department of Mental Health Sciences, Royal Free and University College, London Medical School, London UK
| | | |
Collapse
|