Background:Peritoneal fibrosis is the primary reason that patients with end-stage renal disease (ESRD) have to cease peritoneal dialysis.Peritonitis caused by Gram-negative bacteria such as Escherichia coli (E.coli) were on the rise.We had previously shown that matrine inhibited the formation of biofilm by E.coli.However,the role of matrine on the epithelial-mesenchymal transition (EMT) in peritoneal mesothelial cells under chronic inflammatory conditions is still unknown.Methods:We cultured human peritoneal mesothelial cells (HPMCs) with lipopolysaccharide (LPS) to induce an environment that mimicked peritonitis and investigated whether matrine could inhibit LPS-induced EMT in these cells.In addition,we investigated the change in expression levels of the miR-29b and miR-129-5p.Results:We found that 10 μg/ml of LPS induced EMT in HPMCs.Matrine inhibited LPS-induced EMT in HPMCs in a dose-dependent manner.We observed that treatment with matrine increased the expression of E-cadherin (F=50.993,P ＜ 0.01),and decreased the expression of alpha-smooth muscle actin (F=32.913,P ＜ 0.01).Furthermore,we found that LPS reduced the expression levels of miR-29b and miR-129-5P in HPMCs,while matrine promoted the expression levels of miR-29b and miR-129-5P.Conclusions:Matrine could inhibit LPS-induced EMT in HPMCs and reverse LPS inhibited expressions of miR-29 b and miR-129-5P in HPMCs,ultimately reduce peritoneal fibrosis.These findings provide a potential theoretical basis for using matrine in the prevention and treatment of peritoneal fibrosis.