Investigation of Antidiabetic and Antioxidant Potential of Annona Squamosa Extract: In Vitro and In Vivo Evaluation with Phytochemical Profiling

Abstract

Background: Diabetes mellitus affects over 537 million adults worldwide, with type 2 diabetes characterized by insulin resistance and β-cell dysfunction. Current therapies have limitations, necessitating safer natural alternatives. Annona squamosa, a medicinal plant with traditional antidiabetic use, requires systematic evaluation.
Objective: To investigate the antidiabetic and antioxidant potential of A. squamosa hydroalcoholic extract through integrated in vitro and in vivo approaches.
Methods: The extract was prepared by Soxhlet extraction (70% ethanol) and characterized by HPTLC. Antioxidant activity was evaluated via DPPH and nitric oxide scavenging assays, while antidiabetic potential was assessed through α-amylase and α-glucosidase inhibition. Type 2 diabetes was induced in Sprague-Dawley rats using high-fat diet followed by low-dose streptozotocin (35 mg/kg). Diabetic rats received A. squamosa extract (100, 200, 400 mg/kg) or glibenclamide (5 mg/kg) orally for 4 weeks. Fasting blood glucose, glucose tolerance, insulin sensitivity, lipid profile, serum insulin, and pancreatic histopathology were evaluated.
Results: HPTLC profiling indicated the presence of rutin, quercetin, kaempferol and minor peak corresponding to gallic acid. The extract showed potent antioxidant (DPPH IC₅₀: 50.40 µg/mL; NO IC₅₀: 34.38 µg/mL) and enzyme inhibitory activities (α-amylase IC₅₀: 240.89 µg/mL; α-glucosidase IC₅₀: 218.27 µg/mL). At 400 mg/kg, the extract significantly reduced fasting blood glucose (26.3%), improved glucose-lowering response to exogenous insulin (27.7% AUC reduction), increased serum insulin (9.8%), improved dyslipidemia (50.1% LDL reduction; 88.9% HDL increase), and improved pancreatic architecture.
Conclusion: A. squamosa extract exhibits significant antihyperglycemic and antioxidant activities, supporting its traditional use and potential as a promising natural candidate for further investigation in type 2 diabetes.