Effects of <italic>Celastrus orbiculatus</italic> on Epithelial Mesenchymal Transition in Gastric Mucosal Epithelial Cells by Inhibiting <italic>Lgr</italic>5 Expression from Rats with Gastric Precancerous Lesions.

The extract of Celastrus orbiculatus (COE) has been shown to possess anti-Helicobacter pylori (H. pylori) activity and anticancer effects in vitro and in vivo. However, the molecular mechanism by which COE on precancerous lesions of gastric cancer (PLGC) has not been fully elucidated so far. The purpose of this study is to evaluate the effect and mechanism of COE in the rat model of PLGC, after the rat model of PLGC was successfully constructed. The effects of COE in gastric mucosa of rats with PLGC were tested using routine pathology and a transmission electron microscope (TEM) analysis. The protein and mRNA expression levels of epithelial mesenchymal transition (EMT) markers (E-cadherin, N-cadherin and Vimentin) and leucine-rich repeat-containing G-protein-coupled receptor 5 (Lgr5) were detected adopting techniques of immunohistochemistry (IHC), real-time PCR (RT-PCR) and western blot assays. The body weight of PLGC rats was significantly higher in the COE group than that in the untreated group. The process of PLGC was significantly reversed after COE treatment, shown by observing the changes of histopathological morphology and ultrastructure. Gastric mucosal epithelial cells in COE high dose (COE-H) group showed significantly higher expression levels of E-cadherin, and lower expression levels of N-cadherin, Vimentin and Lgr5 than those of the untreated group. COE could suppress the spatial distribution of Lgr5 + cell changes in PLGC rats. These findings suggested that the therapeutic mechanisms of COE in treating PLGC might be related with its effects on reversing the EMT process and inhibiting Lgr5 expression. [ABSTRACT FROM AUTHOR]