Antidiabetic Effect of Hydro-Ethanolic Leaf Extract of Sclerocarya Birrea (A. Rich.) Hochst in Wistar Rats

Diabetes mellitus, characterized by chronic hyperglycaemia, remains a major global health burden. Limitations of conventional therapies have led to growing interest in medicinal plants like Sclerocarya birrea (A. Rich.) Hochst. widely used in African ethnomedicine. Though prior research has focused more on the stem bark, studies on the leaves, considered more sustainable and traditionally relevant, are still lacking in vivo data. This study assessed the antidiabetic potential of a hydroethanolic leaf extract of Sclerocarya birrea in Wistar rats.

The extract was tested at 25-200 mg/kg in an oral glucose tolerance test (OGTT), and at 100-400 mg/kg in normoglycemic and high fructose-fed, streptozotocin (STZ)-induced type 2 diabetic rats over 21 and 28 days, respectively. Fasting blood glucose, insulin, glycated haemoglobin (HbA1c), glucose transporter type 4 (GLUT4), haematological and biochemical parameters, and histopathological changes in key organs were evaluated.

In the OGTT, the extract significantly reduced postprandial blood glucose at 100 and 200 mg/kg starting from 60 minutes post-glucose load (p < 0.05). In normoglycemic rats, repeated administration over 21 days led to a dose-dependent and statistically significant reduction in fasting blood glucose beginning on day 14 and sustained through day 21 (p < 0.01). In diabetic rats, fasting blood glucose levels were significantly reduced from day 7 onward, with 400 mg/kg producing effects comparable to glibenclamide by day 28 (p < 0.01). Insulin, GLUT4, and HbA1c levels were not significantly altered (p > 0.05). Haematological and biochemical parameters remained within normal ranges, and histopathological examination showed preservation of pancreatic and renal tissues in treated groups.

Sclerocarya birrea leaf extract significantly lowers blood glucose in both normoglycemic and diabetic rats without adverse effects, supporting its potential as a safe plant-based option for diabetes management. Further research is warranted to clarify its mechanisms and long-term impact.