Evaluation of the Antioxidant, Antihyperglycemic and Hypolipidemic Potential of Alstonia scholaris Leaves Extracts in Streptozotocin-Induced Diabetic Rats

The evergreen tree Alstonia scholaris (L) R. Br. (Family: Apocynaceae) is native to Australasia, southern China and the tropics of Asia. Despite its importance as a medicinal plant, little is known about its potential role in complementing standard methods of treating diabetes and its associated consequences. Therefore, the present study scientifically investigated extracts from the leaves of A. scholaris for their antioxidant (in vitro), anti-diabetic, and hypolipidemic effects in rats with type 2 diabetes mellitus. Male Wistar rats were administered streptozotocin (45 mg/kg, i.p.) and fed a high-fat diet to induce type 2 diabetes mellitus. They were treated with 400 mg/kg of an ethyl acetate (EAEAS) and ethanolic (EAAS) extract of A. scholaris leaves after complications persisted. Typical drugs were metformin (200 mg/kg) and canagliflozin (10 mg/kg). In the end, blood was drawn to determine various biochemical parameters such as fasting blood sugar, lipid profile and markers of heart, liver and kidney damage. In addition, the rat’s weight, urinary glucose concentration, urine volume, blood pressure, Electrocardiogram (ECG), and antioxidant potential of EEAS were measured. The pancreas, heart, kidneys, and liver were all subjected to histopathological analysis. A wide range of biochemical and physiological markers, including blood and urine glucose, lipid profile, markers of heart, kidney and liver damage, antioxidant levels and blood pressure, showed significant improvement in response to EEAS. Histopathology illustrates the reverse modulation in heart, kidney, and liver tissue compared to disease control. Based on the data obtained, the EAEAS achieved is far inferior to that required to treat diabetes mellitus. In summary, this present study demonstrates that EEAS (400 mg/kg) can lower blood sugar levels, fight free radicals, and lower bad cholesterol levels in rats with diabetes and complications. Further investigations can be undertaken to explore its mechanism of action at the molecular level.