Protective mechanism of mung bean coat against hyperlipidemia in mice fed with a high-fat diet: insight from hepatic transcriptome analysis

Mung bean coat (MBC) is a good source of dietary fibre and phenolic compounds with medical properties, and can alleviate metabolic diseases. In the present study, the effects of MBC on high fat diet (HFD)-induced hyperlipidemia mice were evaluated, and the underlying mechanisms of MBC against hyperlipidemia from hepatic transcriptional analysis were explored. Four groups of mice were fed a normal control diet or a HFD with or without MBC supplementation (6%, w/w) for 12 weeks. The results demonstrated that MBC supplementation could effectively alleviate HFD-induced obese symptoms, such as body weight gain and white adipose tissue accumulation. Notably, the serum lipid profiles, including total triglyceride, total cholesterol, and low-density lipoprotein cholesterol, were significantly lowered, accompanied by a significant improvement in hepatic steatosis. RNA-sequencing analysis indicated 1126 differential expression genes responding to MBC supplementation, and the PPAR signaling pathway was significantly enriched. Furthermore, MBC supplementation could significantly upregulate the transcriptional expression of lipid transformation (lipidolysis)-related genes (Cpt1b, Cyp7a1, and PPAR-α) and downregulate the transcriptional expression of lipid synthesis-related genes (Scd1, Cd36, and PPAR-γ) to protect against the HFD-induced hyperlipidemia, and they were confirmed by qRCR and western blotting validation. Taken together, the present study provides valuable information for understanding the curative effects and action mechanism of MBC in alleviating hyperlipidemia, and thus may contribute to the development and application of MBC as functional foods or dietary supplement to protect against hyperlipidemia.