Antihyperglycaemic Effect of Ethanol Extract of Trichosanthes cucumerina Leaf in Streptozotocin-induced Diabetes

Diabetes mellitus is a chronic metabolic disorder characterised by persistent hyperglycaemia and impaired glucose metabolism, necessitating the investigation of affordable and naturally derived therapeutic agents. This study evaluated the antihyperglycaemic potential of ethanol extract of Trichosanthes cucumerina (snake gourd) in streptozotocin (STZ)-induced diabetic Wistar rats. Diabetes was experimentally induced using STZ, after which the animals received graded doses of the ethanol extract for 28 days. We assessed treatment effects using fasting blood glucose (FBG), glycated haemoglobin (HbA1c), serum insulin, and the Homeostatic Model Assessment of Insulin Resistance (HOMA-IR) as indicators of glycaemic control and insulin sensitivity. Administration of T. cucumerina extract significantly improved hyperglycaemic indices compared with the untreated diabetic control group (p < 0.05). The highest dose of 400 mg/kg body weight produced the most pronounced effect, reducing FBG to 130.82 ± 4.55 mg/dL and HbA1c to 6.35 ± 0.26%. The treatment also increased serum insulin concentration to 12.62 ± 1.10 µIU/mL and reduced HOMA-IR to 4.32 ± 0.30, indicating improved insulin sensitivity and glucose regulation. The observed antihyperglycaemic activity may be associated with the bioactive phytochemicals present in T. cucumerina, particularly flavonoids and tannins, which may enhance insulin action, reduce oxidative stress, and improve glucose utilisation. Histopathological findings further indicated restoration of pancreatic islet architecture in treated diabetic rats, supporting the biochemical evidence of improved glycaemic control. The findings demonstrate that ethanol extract of T. cucumerina possesses significant antihyperglycaemic activity in STZ-induced diabetic Wistar rats, supporting further investigation of its antihyperglycaemic properties within experimental models.