Curcumin Attenuates Intestinal Mucosal Barrier Dysfunction in Rats with Lactose-Induced Diarrhea via the RhoA/ROCK1 Pathway

Abstract

Background: Diarrhea is a common complication of enteral nutrition affecting the gastrointestinal tract. Curcumin has been shown to prevent a wide range of gastrointestinal maladies by improving the intestinal mucosal barrier function via inhibition of the RhoA (Ras homologyA)/Rho-associated kinase (RhoA/ROCK1) pathway. Objective: To explore the effect of curcumin on intestinal mucosal barrier dysfunction in lactose-induced diarrheal rats and identify its related mechanisms. Methods: Rat fecal parameters, growth and intestinal absorption functions were scored after curcumin treatment. Intestinal mucosal injury and intestinal permeability were evaluated by hematoxylin and eosin (H&E) staining and serum concentrations of FITC (Fluorescein Isothiocyanate)-labeled dextran (FD4). Immunohistochemistry and western blotting were used to measure intestinal epithelial tight junction proteins. The RhoA/ROCK1 pathway was investigated by using western blotting and qRT-PCR (quantificational Real-Time Polymerase Chain Reaction) methods. The findings demonstrated that rat feces abnormalities, growth and intestinal absorption function were corrected by a high dose of curcumin. Results: Curcumin alleviated intestinal mucosal barrier dysfunction and increased intestinal permeability and expression of tight junction proteins by inhibiting RhoA/ROCK1 signaling in diarrheal rats. Conclusions: Our findings indicated that curcumin attenuated intestinal mucosal barrier dysfunction in lactose-induced diarrheal rats via the RhoA/ROCK1 signaling pathway.