The effect of leaf extract P.harmala on streptozotocin-induced apoptosis in pancreatic tissue of rats

Abstract Background and Purpose: Decreased beta-cell mass has a role in the pathogenesis of human type 2 diabetes and in rodent diabetes models. The study of plant extracts is important as they possibly inhibit the reduction of beta cell mass and the islets of Langerhans. The effect of the methanolic extract of P. harmala leaves on pancreatic tissue was investigated in this research. Method: A total of 32 male rats (250 ± 10 g) were acquired from the Pasteur Institute of Iran and randomly divided into four groups (n = 8), including control, diabetic, diabetic and experimental treated with P. harmala leaf extract. Diabetic groups were given 60 mg/kg streptozotocin. After the induction of diabetes on day 10, the methanolic leaf extract (150 mg/kg), extracted by the Soxhlet method, was administered by gavage to groups treated with the extract for 28 days. The extracted content of the P. harmala leaf was then analyzed by HPLC. Subsequently, rats’ serum glucose level was assessed, and the pancreatic tissue was removed. Following H&E and AgNOR staining, the number of beta cells and the diameter of the islets were measured. Finally, the collected data were analyzed by SPSS software. Data: Our results showed that the P. harmala leaf extract is rich in flavonoid compounds. A significant difference was observed in the serum glucose concentrations on days 10, 14, and 28 between the diabetic and control groups (p ≤ 0.001), but there was no meaningful difference between the diabetic group treated with the leaf extract and the diabetic group. The mean islet diameter reduced significantly in the diabetic group relative to the control group (p ≤ 0.01), while the difference was insignificant between the diabetic group treated with the leaf extract and the diabetic group. Besides, the experimental groups under treatment did not show any meaningful difference with the control group. Discussion and Conclusion: In spite of the fact that the P. harmala leaf extract contains flavonoids and phenolic compounds, unlike previous studies, it could not improve the side effects of streptozotocin in the diabetic group.