Electroacupuncture repairs intestinal mucosal barrier in rats with diarrhea-predominant irritable bowel syndrome by regulating adherens junctions through mast cells and microRNAs.

Abstract

OBJECTIVE: To assess whether electroacupuncture (EA) can facilitate the restoration of the intestinal mucosal barrier in rats with diarrhea-predominant irritable bowel syndrome (IBS-D) by regulating adherens junctions through mast cells (MCs) and microRNAs. METHODS: Forty Sprague-Dawley rats were divided into control group and IBS-D group. Rats were given Senna solution via gavage and subjected to a 14-day chronic unpredictable mild stress procedure. Subsequently, rats in the IBS-D group were assigned to a model group, an EA group, and an EA + MC agonist group. Visceral pain threshold and diarrhea index (DI) were measured. Transmission electron microscopy was used to observe the ultrastructure of MCs. Enzyme-linked immunosorbent assay (ELISA) was used to measure tryptase and diamine oxidase (DAO) levels. Western blotting and quantitative polymerase chain reaction (qPCR) techniques were used to evaluate the quantities of E-cadherin and α-catenin. Immunohistochemistry and ELISA were used to assess the levels of F-actin and vinculin. microRNAs from the colon were sequenced, and qPCR was used to validate the sequencing results. In vitro, Caco-2 cells were used to establish the intestinal epithelium model. After transfection with miR-494-3p mimics, qPCR was performed to measure the expression of microRNAs, E-cadherin and α-catenin; the transmittance of fluorescein isothiocyanate-dextran was detected to measure permeability of the cell layer. RESULTS: In the model group, DI, and tryptase and DAO concentration increased; body weight, visceral pain threshold and the expression of E-cadherin, α-catenin, F-actin and vinculin were significantly decreased compared to the control group. This pattern was reversed in the EA group. No significant difference was found between the EA + MC agonist group and the model group. Sequencing revealed that the expression of miR-541-5p and miR-494-3p was significantly higher in the model group and lower in the EA group. Enrichment analyses revealed that the majority of enrichments were associated with adherens junctions. Spearman's correlation tests indicated that the expression of miR-541-5p and miR-494-3p had a positive correlation with serum DAO and colonic tryptase levels, while showing a negative correlation with E-cadherin level. After microRNA mimic transfection, the expression of miR-494-3p and the barrier permeability were significantly increased, and the expression of E-cadherin was significantly decreased. CONCLUSION: In rats with IBS-D, EA may help repair the intestinal barrier function by modulating adherens junctions and cytoskeletal components through the inhibition of MCs; miR-494-3p may play pivotal roles in this process. Please cite this article as: Hou YJ, Zheng HB, Wang K, Jiang HL, Chen Y, Wang L, Zheng QH, Li Y, Zhou SY. Electroacupuncture repairs intestinal mucosal barrier in rats with diarrhea-predominant irritable bowel syndrome by regulating adherens junctions through mast cells and microRNAs. J Integr Med. 2026; 24(1):125-136.