Ping-Ting Xiao,Zhi-Shen Xie,Yu-Jia Kuang,Shi-Yu Liu,Chun Zeng,Ping Li,E-Hu Liu
The mammalian target of rapamycin (mTOR)-sterol regulatory element-binding proteins (SREBPs) signaling promotes lipogenesis. However, mTOR inhibitors also displayed a significant side effect of hyperlipidemia. Thus, it is essential to develop mTOR-specific inhibitors to inhibit lipogenesis. Here, we screened the endogenous inhibitors of mTOR, and identified that FKBP38 as a vital regulator of lipid metabolism. FKBP38 decreased the lipid content in vitro and in vivo via suppression of the mTOR/P70S6K/SREBPs pathway. 3,5,6,7,8,3ʹ,4ʹ-Heptamethoxyflavone (HMF), a citrus flavonoid, was found to target FKBP38 to suppress the mTOR/P70S6K/SREBPs pathway, reduce lipid level, and potently ameliorate hyperlipidemia and insulin resistance in high fat diet (HFD)-fed mice. Our findings suggest that pharmacological intervention by targeting FKBP38 to suppress mTOR/P70S6K/SREBPs pathway is a potential therapeutic strategy for hyperlipidemia, and HMF could be a leading compound for development of anti-hyperlipidemia drugs.
Ethnopharmacological relevance Zexie Tang (ZXT), only two consists with Alismatis Rhizoma (AR) and Atractylodes macrocephala Rhizoma (AM), a classical Chinese medicine formula from Synopsis of the Golden Chamber with a history of 2000 years. Clinical observation in recent years has found that ZXT has excellent lipid-lowering effect. Aim of the study : To explore the potential mechanism of ZXT ameliorates hyperlipidemia based on FKBP38/mTOR/SREBPs pathway. Materials and methods WD-induced hyperlipidemia mice and oleic acid induced cell lipid accumulation model were used to investigate pharmacodynamic . The effect of ZXT on the transcriptional activity of SREBPs was detected by reporter gene assay. Proteins and downstream genes of mTOR/SREBPs pathway were detected in vivo and in vitro . Combined with network pharmacology and HPLC-Q-TOF/MS, the active ingredients were screened and identified. The interaction between active compounds of ZXT and FKBP38 protein were analyzed by docking analysis. Results ZXT decreased TC, TG and LDL-c levels in blood of WD-induced hyperlipidemia mouse model, and improved insulin resistance in vivo . ZXT also reduced TC, TG and lipid accumulation in cells line, and inhibited SREBPs luciferase activity, protein and its target genes expression such as FASN , HMGCR , etc. Meanwhile, ZXT inhibited protein expression levels of p-mTOR, p-S6K, etc in vitro and in vivo . Combined with network pharmacology and HPLC-Q-TOF/MS, 16 active ingredients were screened and identified. Docking results showed that active compounds of ZXT binding to FKBP38 and formed hydrogen bond . Conclusion Our findings highlighted that ZXT ameliorates hyperlipidemia, in which FKBP/mTOR/SREBPs pathway might be the potential regulatory mechanism.
危险品化学品经营许可证（带存储）