Compound oolong tea ameliorates lipid accumulation through AMPK-PPAR pathway of hepatic lipid metabolism and modulates gut microbiota in HFD induced mice.

Based on the modified traditional Chinese formula, Compound Oolong tea (WLT) is composed of six herbal medicines which have beneficial effects. The present study aimed to assess the effects of WLT on lipid metabolism and gut microbiota in the mouse obesity model.Totally 32 mice were randomized into 4 groups including normal control (NC), high-fat diet model (HFD), positive control (PC) receiving atorvastatin 10 mg/kg/d, and WLT group with WLT water extra 300 mg/kg/d. The HFD, PC, WLT groups were fed a High-fat Diet. The results show that body weight, Lee's index, liver index and fat index were reduced in WLT. Moreover, the accumulation of TC, TG, and LDL-C were lower, and the level of serum HDL-C in WLT was higher than HFD. The activities of ALT and AST were reduced, and the glucose tolerance was improved in WLT. Furthermore, the relative gene expression of hepatic such as Pparγ, Lxr, Srebp-1c, Srebp-2, Scd-1, Acc-1, Fas were upregulated, and Hmgcr was downregulated in WLT compared to HFD. The relative protein expression of PPARγ, SREBP-1, FAS, and SCD-1 were decreased, and p-AMPK/AMPK and p-ACC-1/ACC-1 were increased in WLT compared with HFD. In addition, the diversity of gut microbiota was increased in mice, with an increase in Bacteroidota and a decrease in Firmicutes and Desulfovibrionales were decreased in WLT, compared with HFD. Briefly, WLT improves hepatic lipid metabolism through the AMPK-PPAR pathway and regulates the gut microbiome. These findings suggest that WLT could potentially be used as a functional food ingredients for preventing obesity.