Iridoids of Valeriana fauriei contribute to alleviating hepatic steatosis in obese mice by lipophagy

Publication date: May 2020Source: Biomedicine & Pharmacotherapy, Volume 125Author(s): Da-Hye Lee, So-Hyun Park, Yang Hoon Huh, Min Jung Kim, Hyo-Deok Seo, Tae-Youl Ha, Jiyun Ahn, Young-Jin Jang, Chang Hwa JungAbstractNonalcoholic fatty liver disease (NAFLD) is a common risk factor for metabolic syndrome that increases the risk of future cardiovascular disease, stroke, and diabetes. Recently, autophagy has been proposed as a means to prevent NAFLD. We investigated whether substances with autophagy-inducing activity alleviate NAFLD. The Valeriana fauriei (V. fauriei) was selected as a potential autophagy inducer among various natural materials using a Cyto-ID autophagy detection kit. V. fauriei 70 % ethanol extract (VFE) increased LC3II levels in the presence of the lysosomal inhibitor and reduced the GFP/mCherry puncta ratio, suggesting that VFE enhanced autophagy. VFE reduced oleic acid (OA)-induced lipid accumulation and increased the number of autophagosome in hepatocytes. Autophagy induction by VFE is due to inhibition of mTORC1 activity. VFE supplementation reduced fatty liver by downregulating lipogenesis-related genes and increased the autophagy, as revealed by TEM and IHC analysis in the fatty liver. We identified iridoids as main compounds of VFE; didrovaltrate (DI), valeriotriate B (VAL B), valeriotetrate C (VAL C), valtrate (VAL), and valechlorine (VC) were shown to enhance autophagy. These compounds also reduced OA-induced lipid accumulation in an Atg5-dependent ma...
Source: Biomedicine and Pharmacotherapy - Category: Drugs & Pharmacology Source Type: research