Potential of FGF21 in type 2 diabetes mellitus treatment based on untargeted metabolomics

Fibroblast growth factor 21 (FGF21) has promise for treating diabetes and its associated comorbidities. It has been found to reduce blood glucose in mice and humans; however, its underlying mechanism is not known. Here, the metabolic function of FGF21 in diabetes was investigated. Diabetic db/db mice received intraperitoneal injections of FGF21 for 28 days, the serum of each mouse was collected, and their metabolites were analyzed by untargeted metabolomics using UHPLC-MS/MS. It was found that FGF21 reduced blood glucose and oral glucose tolerance without causing hypoglycemia. Moreover, administration of FGF21 reduced the levels of TG and LDL levels while increasing those of HDL and adiponectin. Importantly, the levels of 45 metabolites, including amino acids and lipids, were significantly altered, suggesting their potential as biomarkers. We speculated that FGF21 may treat T2DM through the regulation of fatty acid biosynthesis, the TCA cycle, and vitamin digestion and absorption. These findings provide insight into the mechanism of FGF21 in diabetes and suggest its potential for treating diabetes.