Chemical Profile and Study of the Antidiabetic Effect of Annona squamosa L. Peel

Type 2 Diabetes Mellitus (T2DM) is a public health problem worldwide. The natural products could be a therapeutic alternative because of their bioactive compounds. The objective of this research was to investigate the chemical profile and antidiabetic effect of the peel of Annona squamosa L. (sugar apple) and evaluate a possible mechanism of action. We analyzed the content of secondary metabolites finding the following in 100 g of freeze-dried peel: 5000.13 ± 30.44 mg gallic acid equivalent, 82.04 ± 1.12 mg quercetin equivalent, 3023.07 ± 75.83 mg ascorbic acid, 13,919.07 ± 492.11 mg citric acid, 16,099.56 ± 492.11 mg L-malic acid, 21,346.73 ± 1134.01 mg D-malic acid, 5261.92 ± 34.59 mg tartaric acid, 2920.15 ± 290.13 mg glucose, and 5271.59 ± 562.07 mg fructose. The antihyperglycemic effect of the freeze-dried peel of sugar apple was demonstrated using an oral glucose tolerance test (OGTT) in healthy Wistar rats, discovering an effect at doses of 100 and 200 mg/kg, which was reversed by administering Wortmannin at 1 mg/kg. Regarding the antidiabetic effect in a T2DM model after 14-days of treatment, we found a decrease in non-fasting glucose, and capillary glucose levels during an OGTT, as well as an improvement in insulin response. These results allow us to conclude that sugar apple peel has a beneficial effect on the regulation of glucose levels in both healthy and diabetic rats, seemingly to be related to the insulin signaling pathway; therefore, this could be an alternative therapy for glucose control in prediabetes and T2DM. Graphical Abstract