Kaempferol Ameliorates Non-Alcoholic Fatty Liver Disease by Targeting TRIM56 to Regulate Lipid Metabolism.

Non-alcoholic fatty liver disease (NAFLD) is characterized by excessive hepatic lipid accumulation and can progress to severe liver injury. Kaempferol (KPF), a plant-derived flavonoid, exhibits lipid-regulatory properties. Tripartite motif-containing protein 56 (TRIM56), an E3 ubiquitin ligase, has been reported to interact with fatty acid synthase (FASN) and limit hepatic lipogenesis. This study investigated whether KPF alleviates NAFLD through modulation of TRIM56-associated lipid metabolic pathways. Molecular docking, molecular dynamics simulations, and cellular thermal shift assays (CETSA) were employed to evaluate the interaction between KPF and TRIM56. High-fat diet-induced NAFLD mice and fatty acid-treated HepG2 cells were used to assess the effects of KPF on hepatic lipid accumulation. Histological analysis, lipid profiling, Oil Red O staining, Western blotting, immunofluorescence, and quantitative PCR were performed. Endogenous co-immunoprecipitation examined the association between TRIM56 and FASN, and siRNA-mediated knockdown of TRIM56 evaluated its functional contribution. KPF significantly reduced serum triglyceride, total cholesterol, and low-density lipoprotein cholesterol levels, ameliorated hepatic steatosis in vivo, and decreased intracellular lipid accumulation in vitro. In silico and CETSA analyses supported the engagement of TRIM56 by KPF. KPF restored TRIM56 expression under steatotic conditions, whereas TRIM56 silencing attenuated its lipid-lowering effects. TRIM56 was confirmed to associate with FASN, and KPF treatment suppressed multiple lipogenic enzymes. These findings indicate that KPF alleviates hepatic steatosis, at least in part, through modulation of TRIM56-associated lipogenic pathways, highlighting TRIM56 as a potential therapeutic target in NAFLD.