Vaccarin improves insulin sensitivity and glucose uptake in diet-induced obese mice via activation of GPR120-PI3K/AKT/GLUT4 pathway

Insulin resistance is a risk factor for type 2 diabetes and is often associated with obesity. Vaccarin, a flavonoid found in vaccaria seeds, is commonly used in traditional Chinese medicine for activating blood circulation. Here, we showed that vaccarin ameliorates high-fat diet-induced obesity and insulin resistance in mice by reducing fat accumulation and improving insulin sensitivity in white adipose tissue. Further hyperinsulinemic-euglycemic clamp test revealed enhanced glucose uptake in vaccarin-treated WAT and skeletal muscle, consistent with activated insulin signaling pathway in these tissues. Mechanistically, vaccarin activates adipose tissue GPR120 and subsequently activating the PI3K/AKT/GLUT4 signaling pathway in 3T3-L1 cells. Together, these results reveal an undiscovered function of vaccarin in preventing obesity-related insulin resistance and advocates that vaccarin holds promise for further development as an innovative agent for the prevention of metabolic disorders.