Shenling Baizhu powder alleviates non-alcoholic fatty liver disease by modulating autophagy and energy metabolism in high-fat diet-induced rats

Nonalcoholic fatty liver disease (NAFLD) has emerged as a burgeoning health problem worldwide, but no specific drug has been approved for its treatment. Shenling Baizhu powder (SL) is extensively used to treat NAFLD in Chinese clinical practice. However, the therapeutic components and pharmacological mechanisms of SL against NAFLD have not been thoroughly investigated. This study aims to investigate the pharmacological impact and molecular mechanism of SL on NAFLD. First, we established an animal model of NAFLD by high-fat diet (HFD) feeding, and evaluated the therapeutic efficacy of SL on NAFLD by physiological, biochemical, pathological, and body composition analysis. Next, the effect of SL on autophagic flow in NAFLD rats was evaluated by ultrastructure, immunofluorescence staining, and western blotting. Moreover, an integrated strategy of targeted energy metabolomics and network pharmacology was performed to characterize autophagy-related genes and explore the synergistic effects of SL active compounds. UPLC-MS/MS, molecular docking combined with in vivo and in vitro experiments were conducted to verify the key compounds and genes. Finally, a network was established among SL-herb-compound-genes-energy metabolites-NAFLD, which explains the complicated regulating mechanism of SL on NAFLD. We discovered that SL decreased hepatic lipid accumulation, hepatic steatosis, and insulin resistance, and improved systemic metabolic disorders and pathological abnormalities. Subsequently, an integrated strategy of targeted energy metabolomics and network pharmacology identified quercetin, ellagic acid, kaempferol, formononetin, stigmasterol, isorhamnetin and luteolin as key compounds; catalase (CAT), AKT serine/threonine kinase 1 (AKT), nitric oxide synthase 3 (eNOS), NAD(P)H quinone dehydrogenase 1 (NQO1), heme oxygenase 1 (HO-1) and hypoxia-inducible factor 1 subunit alpha (HIF-1α) were identified as key genes; while nicotinamide adenine dinucleotide phosphate (NADP) and succinate emerged as key energy metabolites. Mechanistically, we revealed that SL may exert its anti-NAFLD effect by inducing autophagy activation and forming a comprehensive regulatory network involving key compounds, key genes, and key energy metabolites, ultimately alleviating oxidative stress, endoplasmic reticulum stress, and mitochondrial dysfunction. Our study demonstrated the therapeutic effect of SL in NAFLD models, and establishes a basis for the development of potential products from SL plant materials for the treatment of NAFLD.