Basic Study
Copyright ©The Author(s) 2020. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastroenterol. Oct 21, 2020; 26(39): 5997-6014
Published online Oct 21, 2020. doi: 10.3748/wjg.v26.i39.5997
Herbal cake-partitioned moxibustion inhibits colonic autophagy in Crohn’s disease via signaling involving distinct classes of phosphatidylinositol 3-kinases
Shi-Yuan Wang, Ji-Meng Zhao, Ci-Li Zhou, Han-Dan Zheng, Yan Huang, Min Zhao, Zhi-Ying Zhang, Lu-Yi Wu, Huan-Gan Wu, Hui-Rong Liu
Shi-Yuan Wang, Ji-Meng Zhao, Ci-Li Zhou, Han-Dan Zheng, Yan Huang, Min Zhao, Zhi-Ying Zhang, Lu-Yi Wu, Huan-Gan Wu, Hui-Rong Liu, Key Laboratory of Acupuncture-Moxibustion and Immunology, Shanghai University of Traditional Chinese Medicine, Shanghai 201203, China
Shi-Yuan Wang, Ji-Meng Zhao, Ci-Li Zhou, Han-Dan Zheng, Yan Huang, Min Zhao, Zhi-Ying Zhang, Huan-Gan Wu, Hui-Rong Liu, Shanghai Research Institute of Acupuncture and Meridian, Shanghai 200030, China
Author contributions: Wang SY, Huang Y, Wu HG, and Liu HR designed the research; Wang SY, Zhao JM, Zhou CL, and Zheng HD performed the experiments; Wang SY, Zhao M, Zhang ZY, and Wu LY collected and analyzed the data; Wang SY wrote the manuscript; all authors reviewed the manuscript prior to its submission, and read and approved the final manuscript.
Supported by the Program of Shanghai Academic Research Leader, No. 17XD1403400; National Natural Sciences Foundation of China, No. 81574079 and No. 81873374; Three-year Action Plan Project of Shanghai Traditional Chinese Medicine Development, No. ZY(2018-2020)-CCCX-2004-01; Chinese Medicine Inheritance and Innovation "100 Million" Talent Project, Qi Huang Scholar; and Shanghai Rising-Star Program, No. 16QA1403400.
Institutional review board statement: This study did not involve human subjects.
Institutional animal care and use committee statement: All animal experiments in this study were performed under guidelines approved by the Animal Ethics Committee of the Shanghai University of Traditional Chinese Medicine (No. PZSHUTCM200403009).
Conflict-of-interest statement: The authors declare no conflicts of interest.
Data sharing statement: No additional data are available.
ARRIVE guidelines statement: The authors have read the ARRIVE guidelines, and the manuscript was prepared and revised according to the ARRIVE guidelines.
Open-Access: This article is an open-access article that was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution NonCommercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/
Corresponding author: Hui-Rong Liu, MD, PhD, Doctor, Professor, Research Fellow, Key Laboratory of Acupuncture-Moxibustion and Immunology, Shanghai University of Traditional Chinese Medicine, No. 650 South Wanping Road, Xuhui District, Shanghai 201203, China. lhr_tcm@139.com
Received: April 16, 2020
Peer-review started: April 16, 2020
First decision: May 1, 2020
Revised: July 14, 2020
Accepted: September 4, 2020
Article in press: September 4, 2020
Published online: October 21, 2020
ARTICLE HIGHLIGHTS
Research background

Recent studies have shown that autophagy dysfunction plays an important role in the pathogenesis of Crohn's disease (CD). Our previous studies have indicated that herbal cake-partitioned moxibustion (HM) can attenuate inflammation and ameliorate pathological changes in colon tissue in CD. However, it is unclear whether HM can regulate colonic autophagy in CD.

Research motivation

The mechanism of HM in the treatment of CD has remained unclear. We sought to elucidate the relevant mechanism by which HM alleviates CD from the perspective of autophagy.

Research objectives

To observe the effect of HM on colonic autophagy in CD rats and further explore the underlying mechanism.

Research methods

2,4,6-trinitrobenzene sulfonic acid (TNBS) was used to establish a rat CD model. The morphology of the colonic mucosa, formation of autophagosomes, and expression of microtubule-associated protein 1 Light chain 3 beta (LC3B) were observed by hematoxylin-eosin staining, electron microscopy, and immunofluorescence staining, respectively. Insulin and rapamycin were used to inhibit and activate colonic autophagy, respectively. The mRNA expression levels of phosphatidylinositol 3-kinase class I (PI3KC1), Akt1, LC3B, sequestosome 1 (p62), and mammalian target of rapamycin (mTOR) and the protein expression levels of interleukin-18 (IL-18), tumor necrosis factor-α (TNF-α), nuclear factor κB/p65 (NF-κB p65), LC3B, p62, coiled-coil myosin-like BCL2-interacting protein (Beclin-1), p-mTOR, PI3KC1, class III phosphatidylinositol 3-kinase (PI3KC3/Vps34), and p-Akt1 were evaluated by RT-qPCR and Western blot analysis, respectively.

Research results

Our experiments revealed that TNBS-induced inflammation activated autophagy in rat colon tissues. HM at the Qihai (CV6) and bilateral Tianshu (ST25) acupoints reversed the expression changes in the autophagy proteins LC3B, p62, Beclin-1, and p-mTOR in colon tissues while ameliorating colonic inflammation (indicated by IL-18, TNF-α, and NF-κB p65 levels) and damage. Furthermore, HM facilitated the repair of colonic epithelial cells. We hypothesized that the mechanisms by which HM alleviates CD may involve the PI3KC1/Akt1/mTOR pathway and the PI3KC3 (VPS34)-Beclin-1 protein complex and confirmed this hypothesis through our experiments.

Research conclusions

HM can activate the PI3KC1/Akt1/mTOR signaling pathway while inhibiting the PI3KC3 (VPS34)-Beclin-1 protein complex, thereby inhibiting overactivated colonic autophagy in CD rats.

Research perspectives

Our findings provide insights into the molecular mechanism of HM and shed new light on a cost-effective and safe therapy for CD.