Aqueous Extracts and Flavonoids Obtained from Annona cherimola Miller as Antidiabetic Treatments Alone and in Combination with Antidiabetic Drugs: In Vivo and In Silico Studies

Background: Annona cherimola Miller (A. cherimola) is traditionally used in Mexico to treat diabetes. Objectives: this study aimed to evaluate the antihyperglycemic activity of the aqueous leaf extracts (AEAcL) and stem (AEAcS) of A. cherimola alone and combined with oral antidiabetic drugs (OADs), as well as to determine their effect on % HbA1c, lipid parameters and toxicity. As well, the study aimed to isolate and identify some of its compounds to propose findings about its mode of action. Methods: Antihyperglycemic activity was evaluated using in vivo models with streptozotocin-induced experimental diabetes in Balb/c mice. Computer tools were used to obtain the pharmacokinetic and toxicological properties of the identified flavonoids; to obtain findings on their potential as α-glucosidase and SGLT1 inhibitors, in vivo and in silico studies were carried out using oral sucrose tolerance (OSTT) and glucose (OGTT) tests and molecular coupling studies. Results: ÇAEs and aSAAcS administered alone at 200 mg/kg showed a significant reduction in hyperglycemia. The best combination was AEAcL + Met (100/500 mg/kg), which significantly reduced hyperglycemic values and the % of HbA1c, TG, and LDL. The flavonoids isolated from AEAcL were identified as rutin, nicotiflorin, and narcissin. The molecular coupling assay and OSTT and OGTT tests showed that the flavonoids could inhibit α-glucosidase and SGLT1. Conclusions: AEAcL shows significant antihyperglycemic and antihyperlipidemic activity in murine models of diabetes, both alone (100 mg/kg) and in combination with metformin (100/500 mg/kg). Isolated flavonoids (rutin, nicotiflorin, and narcissine) appear to be partly responsible for these effects, although they have pharmacokinetic limitations. In silico and in vivo studies suggest a possible mechanism of action by inhibition of α-glucosidase and SGLT1.