Pawpaw (Asimina triloba) Seed Extract Suppresses High-Fat Diet-Induced Obesity in Mice

Asimina triloba (pawpaw), a member of the Annonaceae family, contains various bioactive phytochemicals, including alkaloids, polyphenols, and acetogenins. In this study, the effects of pawpaw seed extract (PSE) on obesity and plasma lipid concentrations were investigated in mice with high-fat diet (HFD)-induced obesity. Male C57BL/6J mice were fed a normal diet (ND) or an HFD for two weeks. The mice in the latter group were then divided into three groups: HFD, L-PSE, and H-PSE. Following a two-week adaptive period, the L-PSE and H-PSE groups were fed an experimental diet containing 250 mg and 500 mg PSE/kg of HFD, respectively, for two weeks. Mice in the HFD group exhibited significantly higher body weights than that of mice in the ND group. A significant decrease in body weight was observed in the H-PSE group compared with that in the HFD group. The perirenal, testicular, and total visceral fat masses of the mice in the H-PSE group were consistently lower than those of the mice in the HFD group. Administration of high-dose PSE decreased the expression of Fasn (encoding fatty acid synthase) and Dgat2 (encoding diglyceride acyltransferase 2) in testicular fat tissues. However, PSE administration did not decrease blood glucose and plasma cholesterol levels compared with that in the HFD group. These findings suggest that the administration of PSE suppresses HFD-induced obesity in mice, while its hypoglycemic or cholesterol-lowering actions are less pronounced.