Thwarting Metabolic Dysfunction-Associated Fatty Liver Disease (MAFLD) with Common Bean: Dose- and Sex-Dependent Protection against Hepatic Steatosis

Hepatic steatosis signifies onset of metabolic dysfunction-associated fatty liver disease (MAFLD) caused by disrupted metabolic homeostasis compromising liver function. Regular consumption of common beans reduces the risk of metabolic impairment, but its effective dose, the impact of biological sex, and underlying mechanisms of action are unknown. We fed female and male C57BL6/J mice with obesogenic yet isocaloric diets containing 0%, 17.5%, 35%, and 70% of total dietary protein derived from cooked whole common beans. Liver tissue was collected for histopathology, lipid quantification, and RNA-seq analyses. Beans qualitatively and quantitatively diminished hepatic fat deposition at the 35% dose in female and 70% dose in male mice. Bean-induced differentially expressed genes (DEGs) most significantly mapped to hepatic steatosis and revealed dose-responsive inhibition of de novo lipogenesis markers (Acly, Acaca, Fasn, Elovl6, Scd1, etc.) and triacylglycerol biosynthesis, activation of triacylglycerol degradation, and downregulation of sterol regulatory element-binding transcription factor 1 (SREBF1) signaling. Upregulated fatty acid β-oxidation was more prominent in females, while suppression of Cd36-mediated fatty acid uptake—in males. Sex-dependent bean effects also involved DEGs patterns downstream of peroxisome proliferator-activated receptor α (PPARα) and MLX-interacting protein-like (MLXIPL). Therefore, biological sex determines amount of common bean in the diet required to prevent hepatic lipid accumulation.