Research[Therapeutic effect comparison and mechanisms of Hedysari Radix, Astragali Radix, and Hedysari Radix polysaccharides in improving non-alcoholic fatty liver via regulating mitophagy].
This study aims to compare the therapeutic effects of Hedysari Radix, Astragali Radix, and Hedysari Radix polysaccharide(HPS) in non-alcoholic fatty liver disease(NAFLD) and to investigate the mechanisms of action by which these TCMs improve NAFLD through the regulation of mitophagy. NAFLD mouse models were established by feeding C57BL/6J mice a high-fat diet for 12 weeks. The mice were then randomly divided into a model group, a metformin group, a Hedysari Radix decoction group, an Astragali Radix decoction group, and an HPS group. The mice in the treatment groups received intragastric administration for four consecutive weeks. C57BL/6J mice fed a normal diet served as the control group. The mice in the control and model groups were administered an equal volume of distilled water by gavage. General conditions of the mice were observed, and at week 16, serum and liver tissues were collected. Serum biochemical indices were measured to evaluate liver function. The pathological changes in the liver were observed by hematoxylin-eosin(HE) and oil red O stainings. Mitochondrial morphological changes in the liver were observed by using a transmission electron microscope. The contents of reactive oxygen species(ROS), malondialdehyde(MDA), and superoxide dismutase(SOD) were measured using kits. Fasting insulin(FINS) levels were measured by enzyme-linked immunosorbent assay(ELISA). The mRNA and protein expression levels of PTEN-induced putative kinase 1(PINK1), parkin, microtubule-associated protein 1 light chain 3(LC3), and sequestosome 1(P62) were detected by real-time quantitative polymerase chain reaction(RT-qPCR) and Western blot. The results show that, compared with those in the control group, mice in the model group exhibit significantly increased body weight, liver weight, liver index, fasting blood glucose, insulin, alanine aminotransferase(ALT), aspartate aminotransferase(AST), total cholesterol(TC), triglyceride(TG), low-density lipoprotein(LDL), and triglyceride-glucose index(TyG), while high-density lipoprotein(HDL) levels are significantly decreased. Marked hepatocellular steatosis was observed, accompanied by mitochondrial structural damage and morphological abnormalities. ROS and MDA levels in liver tissue were significantly increased, whereas SOD activity was significantly decreased. RT-qPCR and Western blot results show that the expression levels of PINK1, parkin, and LC3 are decreased in the model group, whereas the expression level of ubiquitin-binding protein P62 is increased. Compared with those in the model group, after treatment with Hedysari Radix, Astragali Radix, and HPS, the mice in these groups exhibited significantly reduced body weight, liver weight, liver index, fasting blood glucose, insulin, ALT, AST, TC, TG, LDL, and TyG levels and significantly increased HDL levels. Hepatic tissue steatosis was markedly alleviated; mitochondrial morphology tended to normalize; ROS and MDA contents were significantly decreased; SOD activity was significantly increased. RT-qPCR results show that the mRNA expression levels of PINK1, parkin, and LC3 are increased in the Hedysari Radix and Astragali Radix decoction groups, while the mRNA expression level of P62 is decreased. In the HPS group, the mRNA expression of LC3 was increased, whereas that of P62 was decreased. Western blot results show that protein expression levels of PINK1, parkin, and LC3 were significantly increased in the Hedysari Radix and Astragali Radix decoction groups, whereas the expression level of P62 was significantly decreased. In the HPS group, the expression level of LC3 was increased, while that of P62 was decreased. In conclusion, Hedysari Radix and Astragali Radix can improve oxidative stress and liver injury of NAFLD mice by regulating mitophagy through the PINK1/Parkin pathway, with Hedysari radix showing superior efficacy. Although HPS can increase LC3 expression and decrease P62 expression, it does not exert a significant regulatory effect on the core proteins of the PINK1/Parkin pathway, and its specific mechanism requires further investigation.
