Asian Journal of Advances in Medical Science

Diabetes-associated hyperglycaemia and dyslipidaemia are metabolic disturbances for which plant-derived materials are being investigated. This study compared the hypoglycaemic and hypolipidaemic effects of methanolic rind extracts of Cucumis sativus and Citrullus lanatus, administered separately and together, in alloxan-induced diabetic Wistar rats. Thirty male Wistar rats were used. Diabetes was induced with alloxan monohydrate (150 mg/kg). The treatment regimens comprised C. sativus rind extract (200 mg/kg), C. lanatus rind extract (200 mg/kg), a combined preparation (100 mg/kg of each extract) and metformin, alongside control groups. Treatments were administered orally for 21 days. Fasting blood glucose, serum total cholesterol, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol and triglycerides were assessed; qualitative phytochemical screening was also undertaken. Both extracts contained alkaloids, flavonoids, tannins, saponins, phenols and terpenoids. By day 21, fasting blood glucose was 6.22 mmol/L with C. sativus, 6.61 mmol/L with C. lanatus, 5.44 mmol/L with the combined preparation and 5.00 mmol/L with metformin, compared with 15.67 mmol/L in the diabetic control group. The combined preparation also showed lower total cholesterol, low-density lipoprotein cholesterol and triglycerides, and higher high-density lipoprotein cholesterol, than either individual extract. The combined rind extracts were associated with greater improvements in the measured metabolic indices than individual extracts under the experimental conditions. Additional studies are needed to characterise active constituents, mechanisms and longer-term safety.