Chaihu Shugan Powder inhibits interstitial cells of cajal mitophagy through USP30 in the treatment of functional dyspepsia

Ethnopharmacological relevance: Chaihu Shugan Powder (CHSGP) has significant clinical efficacy in the treatment of functional dyspepsia (FD), but the specific mechanism requires further study. Aim of study: The aim of this study was to investigate the therapeutic effect of CHSGP on FD rats and the underlying mechanism of the effect on interstitial cells of cajal (ICC) mitophagy. Materials and methods: The tail-clamping stimulation method was utilized to establish an FD rat model in vivo. Gastric emptying rate and small intestinal propulsion rate test, H&E staining, and Immunohistochemistry were conducted to evaluate the therapeutic effects of CHSGP on FD rats. In vitro, the regulatory effect of CHSGP on CCCP-mediated ICC mitophagy was further investigated by CCK8, Transmission electron microscope, immunofluorescence co-staining, Quantitative polymerase chain reaction and Western blot to reveal the potential mechanisms of CHSGP inhibited ICC mitophagy. Results: Animal experiments provided evidence that CHSGP promoted gastric motility, increased ICC numbers, reduced Parkin expression, and elevated USP30 expression in FD rats. In vitro, further mechanism research demonstrated that CHSGP decreased LC3II/LC3I,PINK1,Parkin,PHB2 protein expression and increased USP30 protein expression. Furthermore, CHSGP increased Mfn2 protein expression by suppressing activation of the PINK1/Parkin pathway when USP30 is knocked down, consequently reducing CCCP-induced ICC mitophagy. Conclusions: These results suggest that CHSGP may treat FD against CCCP-induced ICC mitophagy by the upregulation of via PINK1/Parkin pathway.