Mechanism of Qifu Lizhong Decoction in Repairing Intestinal Mucosal Barrier and Improving Ulcerative Colitis via Myosin Light Chain Kinase （MLCK）/ Phosphorylated Myosin Light Chain （p-MLC） Signaling Pathway
10.13422/j.cnki.syfjx.20260439
- VernacularTitle:基于MLCK/p-MLC信号通路探讨芪附理中汤修复肠黏膜屏障改善溃疡性结肠炎的作用机制
- Author:
Junmei TANG
1
;
Zhengwu QU
1
;
Chunrun LI
1
;
Lingling YUAN
1
;
Xuli YANG
1
;
Yanwei HAO
1
;
Yi ZHANG
1
Author Information
1. Hospital of Chengdu University of Traditional Chinese Medicine， Chengdu 610072，China
- Publication Type:Journal Article
- Keywords:
ulcerative colitis;
Qifu Lizhong decoction;
intestinal barrier;
tight junction;
myosin light chain kinase （MLCK）/phosphorylated myosin light chain （p-MLC） signaling pathway
- From:
Chinese Journal of Experimental Traditional Medical Formulae
2026;32(19):174-184
- CountryChina
- Language:Chinese
-
Abstract:
ObjectiveTo explore the mechanism by which Qifu Lizhong decoction restores intestinal mucosal barrier function in ulcerative colitis （UC） by regulating the myosin light chain kinase （MLCK）/phosphorylated myosin light chain （p-MLC） signaling pathway. MethodsA rat model of UC with spleen-kidney Yang deficiency syndrome and an in vitro intestinal barrier injury model were established. In vivo experiments were conducted to evaluate the body weight， disease activity index （DAI） scores， and changes in colonic pathological morphology in each group of rats. Enzyme-linked immunosorbent assay （ELISA） was used to measure the levels of tumor necrosis factor-α （TNF-α）， interleukin-1β （IL-1β）， and myeloperoxidase （MPO）. Transmission electron microscopy （TEM） was employed to observe the morphology and structure of tight junctions （TJ） in rat colonic epithelium. In vitro experiments were conducted to observe the morphology of F-actin in human colon adenocarcinoma cell line-2（Caco-2） cells by phalloidin staining. Combining both in vivo and in vitro approaches， immunohistochemistry （IHC）， immunofluorescence （IF）， and Western blot were applied to detect the expression and phosphorylation levels of TJ proteins ［zonula occludens-1 （ZO-1）， Occludin， Claudin-1］ as well as key proteins in the MLCK/p-MLC signaling pathway. ResultsIn vivo experiments demonstrated that， compared with the normal group， the model group exhibited significant body weight loss， elevated DAI scores and histopathological scores （P<0.01）， increased colonic TNF-α， IL-1β， and MPO levels （P<0.01）. TJ structures were disrupted， and the expression of ZO-1， Occludin， and Claudin-1 was significantly reduced （P<0.05， P<0.01）. The protein expression levels of myosin light chain （MLC）， MLCK， phosphorylated （p）-MLC， and p-MLCK significantly increased （P<0.01）. Compared with the model group， all Qifu Lizhong decoction dose groups exhibited increased body weight， as well as significantly decreased DAI scores and histopathological scores （P<0.05， P<0.01）. The colonic levels of MPO， TNF-α， and IL-1β were significantly reduced （P<0.05， P<0.01）. In the Qifu Lizhong decoction + inhibitor group， the expression of TJ proteins ZO-1， Occludin， and Claudin-1 significantly increased （P<0.01）， while the protein expression levels of MLC， MLCK， p-MLC， and p-MLCK were significantly reduced （P<0.01）. In vitro experiment results showed that， compared with the normal group， the TNF-α group exhibited disordered cytoskeletal architecture， weakened fluorescence signals of ZO-1， Occludin， and Claudin-1， and significantly elevated protein expression levels of MLC， MLCK， p-MLC， and p-MLCK （P<0.01）. Compared with the TNF-α group， the Qifu Lizhong decoction + inhibitor group restored the ordered arrangement of the F-actin cytoskeleton， normalized the expression and localization of TJ proteins ZO-1， Occludin， and Claudin-1， and significantly decreased the protein expression levels of MLC， MLCK， p-MLC， and p-MLCK （P<0.01）. ConclusionQifu Lizhong decoction may exert its therapeutic effects on UC by inhibiting the MLCK/p-MLC signaling pathway， thereby stabilizing TJ structure and repairing intestinal barrier integrity.
