[Modified Chaihu Shugan Powder alleviates cholesterol gallstones in mice with liver depression syndrome by regulating gut microbiota and bile acid metabolism].

OBJECTIVESTo investigate the therapeutic effect of modified Chaihu Shugan San (CHSGS) in mice with cholesterol gallstones (CS) and liver depression syndrome and its potential mechanism.

METHODSSixty male C57BL/6 mice were randomly divided into blank group (n=9) and model group (n=51) with CS induced by high-lithogenic diet feeding. After verification of successful modeling in 3 mice, the remaining 48 mouse models were divided into CS group, CS-liver depression (CS-LD) group, CHSGS group, and ursodeoxycholic acid (UDCA) group, and the latter 3 groups were subjected to CS-LD modeling by chronic unpredictable mild stress (CUMS) and solitary raising and treated with saline, CHSGS or UDCA gavage for 3 weeks. The mice were assessed for general state, body weight, depressive behavior, ileal pathologies, biliary total cholesterol (TC) and total bile acid (TBA) levels, and ileal mRNA expressions of TGR5, GLP-1, and GLP-2 using q-PCR. 16S rDNA sequencing and metabolomics studies were used to analyze fecal microbiota and bile acids of the mice.

RESULTSCompared to the blank control and CS mice, the CS-LD mouse models showed decreased body weight, depressive behaviors, enlarged gallbladder with crystals, intestinal villi damage, increased biliary TC, decreased TBA, and increased ileal GLP-1/2 and TGR5 mRNA expressions, which were obviously improved by CHSGS treatment. Microbiota analysis revealed decreased alpha diversity in CS and CS-LD groups, with altered abundances of Verrucomicrobiota, Akkermansia, Bacteroidota, and Muribaculaceae. Bile acid profiling revealed significant upregulation of TDCA, DCA, and GDCA in CS group and increased CA and 3-ketodeoxycholic acid levels in CS-LD group. Correlation analysis suggested positive correlations between pro-lithogenic bile acids and the harmful gut bacteria.

CONCLUSIONSModified CHSGS alleviates liver depression and cholesterol gallstones in mice likely by ameliorating gut microbiota dysbiosis and bile acid metabolism disorders.