ObjectiveTo explore the mechanism of action of Wendantang on ApoE^-/- hyperlipidemic mice using non-targeted metabolomics technology.MethodsMale C57BL/6J mice served as the normal control group （n=6）， and they were fed with regular chow， while male ApoE^-/- mice constituted the high-fat group （n=30）， and they were fed with a 60% high-fat diet. After 11 weeks of model establishment， the mice in the high-fat group were randomly divided into the model group， simvastatin group （3.3 mg·kg^-1）， and high-dose， medium-dose， and low-dose groups of Wendantang （26， 13， 6.5 g·kg^-1， respectively， in terms of crude drug amount）， with six mice in each group. The normal control group and the model group were gavaged with an equivalent volume of normal saline， and all groups continued to be fed their respective diets， receiving daily medication for 10 weeks with weekly body weight measurements. Serum levels of total cholesterol （TC）， triglycerides （TG）， high-density lipoprotein cholesterol （HDL-C）， low-density lipoprotein cholesterol （LDL-C）， free fatty acids （NEFA）， blood glucose （GLU）， alanine aminotransferase （ALT）， and aspartate aminotransferase （AST） were detected in the mice. Pathological changes in liver tissue were observed using hematoxylin-eosin （HE） staining， and ultra-performance liquid chromatography-quadrupole time-of-flight mass spectrometry （UPLC-Q-TOF-MS/MS） was employed for metabolomic analysis of mouse liver tissue.ResultsCompared to the normal control group， the model group exhibited significantly increased body weight， blood lipid levels， and liver function （P<0.05， P<0.01）， with disordered liver tissue structure， swollen hepatocytes， and accompanying vacuolar fatty degeneration and inflammatory cell infiltration. Compared to the model group， the simvastatin group and Wendantang groups showed significantly reduced body weight， TG， NEFA， GLU， ALT， and AST levels （P<0.05， P<0.01）， with a significant increase in HDL-C levels （P<0.05， P<0.01）， demonstrating a dose-dependent effect. The lesion of the liver tissue section was obviously improved after administration， tending towards a normal liver tissue morphology. Analysis of liver metabolites revealed 86 differential metabolites between the normal control group and the model group， with the high-dose group of Wendantang able to regulate 56 of these metabolites. Twenty-two differential metabolites associated with hyperlipidemia were identified， mainly including chenodeoxycholic acid， hyocholic acid， taurine， glycocholic acid， dihydroceramide， hydroxy sphingomyelin C14∶1， arachidonic acid， and linoleic acid， enriching 22 metabolic pathways， with 4 being the most significant （P<0.05）， namely primary bile acid biosynthesis， sphingolipid metabolism， unsaturated fatty acid biosynthesis， and linoleic acid metabolism pathways.ConclusionWendantang can improve blood lipid levels and liver function in ApoE^-/- hyperlipidemic mice， which may be related to the regulation of primary bile acid biosynthesis， sphingolipid metabolism， unsaturated fatty acid biosynthesis， and linoleic acid metabolism pathways.

Wendantang;hyperlipidemia;liver;ApoE^-/- mice;metabolomics