Published online Sep 7, 2020. doi: 10.3748/wjg.v26.i33.4945
Peer-review started: May 17, 2020
First decision: June 18, 2020
Revised: June 27, 2020
Accepted: August 12, 2020
Article in press: August 12, 2020
Published online: September 7, 2020
Processing time: 109 Days and 22 Hours
Intestinal mucosal barrier disorder plays a very important role in the pathogenesis of ulcerative colitis (UC). Recent studies have revealed that impaired autophagy is associated with intestinal mucosal dysfunction in the mucosa of colitis mice.
Resveratrol can regulate autophagy in the treatment of a few inflammatory diseases. Recently, few studies have indicated that resveratrol can alleviate clinical colitis activity in patients with active UC, while the mechanism for its anti-inflammatory effect remains elusive.
The aim of the study was to explore the effect and mechanism of resveratrol on protecting the integrity of the intestinal mucosal barrier and anti-inflammation in dextran sulfate sodium (DSS)-induced ulcerative colitis.
DSS-induced ulcerative colitis was induced by DSS, then the disease activity index was used to assess the severity of colitis. Inflammatory cytokines were detected by enzyme-linked immunosorbent assay. Tissue sections were stained with haematoxylin and eosin, and mucosal damage was evaluated by mean histological score. The expression of occludin and ZO-1 was detected by immunohistochemical analysis. Reverse transcription-polymerase chain reaction and Western-blot were used to analyze autophagy-related gene expression, and morphology of autophagy was observed by transmission electron microscopy.
The resveratrol treatment group showed a 1.72-fold decrease in disease activity index scores and 1.42-, 3.81-, and 1.65-fold decrease in the production of the inflammatory cytokines tumor necrosis factor-α, interleukin-6 and interleukin-1β, respectively, in DSS-induced colitis mice compared with DSS group (P < 0.05). The expression of the tight junction proteins occludin and ZO-1 in DSS model group was reduced, while in resveratrol-treated colitis group was increased. Resveratrol also increased the levels of LC3B (1.39-fold compared with DSS group) and Beclin-1 (1.49-fold compared with DSS group) (P < 0.05), as well as the number of autophagosomes, which implies that the resveratrol may alleviate intestinal mucosal barrier dysfunction in DSS-induced UC mice by enhancing autophagy.
Resveratrol treatment reduces the expression of inflammatory factors, increases the expression of tight junction proteins and alleviates UC intestinal mucosal barrier dysfunction; this effect is achieved via the regulation of autophagy in intestinal epithelial cells.
This work suggests that resveratrol may be useful as a new approach to treat UC by enhancing autophagy. Further study of the functionary mechanism will help us to understand the role of resveratrol in colitis and provide a theoretical basis for future clinical application.