Basic Study
Copyright ©The Author(s) 2018. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastroenterol. Sep 21, 2018; 24(35): 4036-4053
Published online Sep 21, 2018. doi: 10.3748/wjg.v24.i35.4036
Daikenchuto (Da-Jian-Zhong-Tang) ameliorates intestinal fibrosis by activating myofibroblast transient receptor potential ankyrin 1 channel
Keizo Hiraishi, Lin-Hai Kurahara, Miho Sumiyoshi, Yao-Peng Hu, Kaori Koga, Miki Onitsuka, Daibo Kojima, Lixia Yue, Hidetoshi Takedatsu, Yu-Wen Jian, Ryuji Inoue
Keizo Hiraishi, Lin-Hai Kurahara, Miho Sumiyoshi, Yao-Peng Hu, Ryuji Inoue, Department of Physiology, Graduate School of Medical Sciences, Fukuoka University, Fukuoka 8140180, Japan
Kaori Koga, Miki Onitsuka, Department of Pathology, Faculty of Medicine, Fukuoka University, Fukuoka 8140180, Japan
Daibo Kojima, Department of Gastroenterological Surgery, Faculty of Medicine, Fukuoka University, Fukuoka 8140180, Japan
Lixia Yue, Department of Cell Biology, University of Connecticut Health Center, Farmington, CT 06030, United States
Hidetoshi Takedatsu, Department of Gastroenterology and Medicine, Faculty of Medicine, Fukuoka University, Fukuoka 8140180, Japan
Yu-Wen Jian, College of Letters and Science, University of California, Davis, CA 95616, United States
Author contributions: Kurahara LH designed the experiments and wrote the paper, Hiraishi K, Kurahara LH and Sumiyoshi M performed most of the experiments and analyzed the data; Hu YP conducted patch-clamp experiments and analyzed the obtained data; Koga K and Onitsuka M performed the pathological analysis; Yue L provided comments; Kojima D and Takedatsu H gave clinical advice, recruited study participants, and performed the biopsies and surgical resections of tissue; Jian YW created the graphical abstract; and Inoue R supervised the study and assisted in the preparation of the manuscript.
Supported by MEXT, KAKENHI, No. 15K08978, No. 22790677 and No. 25860571; a MEXT-Supported Program supporting research activities of female researchers; the Clinical Research Foundation; and the Central Research Institute of Fukuoka University, No. 151045 and No. 147104.
Institutional review board statement: The study was reviewed and approved by the Clinical Research Ethics Committee of Fukuoka University, No. 15-10-04.
Institutional animal care and use committee statement: All procedures involving animals were reviewed and approved by the Animal experiment ethics committee of Fukuoka University, No. 1709099; and the Genetic Modification Experiment Safety Commission of Fukuoka University approved experiments on genetically modified animals, No. 167.
Conflict-of-interest statement: The authors declare that they have no competing interests.
Data sharing statement: Readers can request the data of this paper by contacting us via hailin@fukuoka-u.ac.jp.
ARRIVE guidelines statement: The authors have read the ARRIVE guidelines, and the manuscript was prepared and revised according to the ARRIVE guidelines.
Correspondence to: Lin-Hai Kurahara, PhD, Lecturer, Department of Physiology, Fukuoka University School of Medicine, Fukuoka 8140180, Japan. hailin@fukuoka-u.ac.jp
Telephone: +81-92-8011011-3236 Fax: +81-92-8656032
Received: May 16, 2018
Peer-review started: May 16, 2018
First decision: June 13, 2018
Revised: July 6, 2018
Accepted: July 22, 2018
Article in press: July 22, 2018
Published online: September 21, 2018
Processing time: 126 Days and 23.9 Hours
Abstract
AIM

To investigate the anti-fibrotic effects of the traditional oriental herbal medicine Daikenchuto (DKT) associated with transient receptor potential ankyrin 1 (TRPA1) channels in intestinal myofibroblasts.

METHODS

Inflammatory and fibrotic changes were detected in a 2,4,6-trinitrobenzenesulfonic acid (TNBS) chronic colitis model of wild-type and TRPA1-knockout (TRPA1-KO) mice via pathological staining and immunoblotting analysis. Ca2+ imaging experiments examined the effects of DKT and its components/ingredients on intestinal myofibroblast (InMyoFib) cell TRPA1 channel function. Pro-fibrotic factors and transforming growth factor (TGF)-β1-associated signaling were tested in an InMyoFib cell line by qPCR and immunoblotting experiments. Samples from non-stenotic and stenotic regions of the intestines of patients with Crohn’s disease (CD) were used for pathological analysis.

RESULTS

Chronic treatment with TNBS caused more severe inflammation and fibrotic changes in TRPA1-KO than in wild-type mice. A one-week enema administration of DKT reduced fibrotic lesions in wild-type but not in TRPA1-KO mice. The active ingredients of DKT, i.e., hydroxy α-sanshool and 6-shogaol, induced Ca2+ influxes in InMyoFib, and this was antagonized by co-treatment with a selective TRPA1 channel blocker, HC-030031. DKT counteracted TGF-β1-induced expression of Type I collagen and α-smooth muscle actin (α-SMA), which were accompanied by a reduction in the phosphorylation of Smad-2 and p38-mitogen-activated protein kinase (p38-MAPK) and the expression of myocardin. Importantly, 24-h incubation with a DKT active component Japanese Pepper increased the mRNA and protein expression levels of TRPA1 in InMyoFibs, which in turn negatively regulated collagen synthesis. In the stenotic regions of the intestines of CD patients, TRPA1 expression was significantly enhanced.

CONCLUSION

The effects of DKT on the expression and activation of the TRPA1 channel could be advantageous for suppressing intestinal fibrosis, and benefit inflammatory bowel disease treatment.

Keywords: Intestinal fibrosis; Myofibroblast; Transient receptor potential ankyrin 1; Crohn’s disease; Collagen; α-smooth muscle actin

Core tip: Active ingredients of the famous Chinese medicine Da-Jian-Zhong-Tang (Daikenchuto; DKT), i.e., hydroxy α-sanshool and 6-shogaol, induced Ca2+ influxes in intestinal myofibroblast (InMyoFib), which were antagonized by co-treatment with a selective transient receptor potential ankyrin 1 (TRPA1) channel blocker HC-030031. DKT counteracted the transforming growth factor (TGF)-β1-induced expression of Type I collagen, α-smooth muscle actin (α-SMA), and this was accompanied by a reduction in fibrosis signaling downstream of the TGF-β1 receptor. Importantly, a 24-h incubation with another DKT active ingredient of Japanese Pepper increased mRNA and protein expression in TRPA1, which in turn negatively regulated collagen synthesis in InMyoFibs. In stenotic regions of the intestines of patients with Crohn’s disease, TRPA1 expression was significantly increased.