Protective and therapeutic effects of Phoenix dactylifera leaf extract on pancreatic β-cells and diabetic parameters in streptozotocin-induced diabetic rats

The present study is designed to assess the impact of Phoenix dactylifera (P.d) leaf extract on plasma glucose concentration, diabetic parameters, and the number of β-cells in streptozotocin (STZ)-induced diabetic rats. In this study, diabetes was induced in male Wistar rats via intraperitoneal administration of STZ (55 mg/kg). In this study, 49 rats were divided into seven groups randomly (n = 7 per group). Our three treatment groups for 42 days were given 250 mg/kg of P.d extract, 500 mg/kg of P.d extract, and 5 mg/kg glibenclamide orally, respectively. Then, the animals were anesthetized and blood samples were obtained from puncturing the retro-orbital sinus at the initial and end of the experiment and finally sacrificed. Fasting blood glucose (FBG) levels and serum biochemical parameters including malondialdehyde (MDA), glycosylated hemoglobin (HbA1c) and insulin level were measured. Pancreatic tissue was identified by immunohistochemistry and morphometric analysis which was used to evaluate β-cells. Statistical analysis was done by applying SPSS statistical software; ANOVA and Tukey’s test were used to assess data in the control and treatment groups. Blood glucose significantly decreased after daily oral administration of P.d in diabetic rats (P < 0.05). HbA1c and MDA also declined in P.d extract- and glibenclamide-treated animals compared with those in the control group (P < 0.05). Plasma insulin level also rose in treatment groups compared with that in the control group (P < 0.05). The β-cell number increased significantly in the P.d-treated diabetic rats. According to the results of this study, P.d extract might decrease hyperglycemia and improve complications of diabetes in diabetic patients. © 2020, Springer-Verlag London Ltd., part of Springer Nature.