Benefits of the soluble and insoluble fractions of bitter gourd in mice fed a high-fat diet

Background Bitter gourd (BG) fruit powder was previously showed to prevent high-fat diet (HFD)-induced metabolic disorders in mice. In current study, we investigated the beneficial difference of the water soluble (S-BG) and insoluble fractions (IS-BG) of bitter gourd. Results Compared to normal chow diet, the HFD induced greater body weight gain and increased fat mass accompanied by impaired insulin sensitivity, elevated serum lipids and inflammation. Supplementation of BG, S-BG, and IS-BG showed similar beneficial effects and restored the metabolic changes in mice. Interestingly, BG showed no effect on fat mass, which was decreased by both S-BG and IS-BG. Additionally, S-BG and IS-BG inhibited the SREBP-1/FAS pathway, thereby decreasing liver cholesterol accumulation, while only BG showed improvement on mitochondrial activity. Conclusion These results further support the position that bitter gourd has multiple active ingredients and that both fractions have beneficial effects on metabolic disorders.