Immunohistochemical and biochemical study of the effect of Rheum ribes on the pancreas of diabetic rats

Background and objective: Reports indicate that Rheum ribes has antihyperglycemic effects. This study aimed to find out the hypoglycemic effects of aqueous extract of Rheum ribes on the pancreatic tissue of diabetic male rats and compare the results of both histological and biochemical findings with that of metformin. Methods: Thirty-two albino male rats were divided into four groups with eight animals for each group; 1st group as normal control, 2nd group as alloxan induced diabetics, 3rd group as diabetic treated with Rheum ribes, and 4th groups as diabetic treated with Metformin. The body weight and fasting blood glucose levels of all the rats were recorded at weekly intervals during the experimental period. Biochemical, histochemical, and immunohistochemical investigations were used. Results: Diabetic rats showed a decrease in serum amylase with marked elevation in blood glucose level. Histological examination of the pancreas from diabetic rats revealed an increase in the thickness of the basement membrane of the blood vessels and capillaries in islets of Langerhans, as well as decreased activity of Beta-cells and increase the activity of Alpha and Delta cells using both Periodic Acid Schiff stain and immunohistochemistry techniques. Administration of aqueous extract of Rheum ribes caused significant and dramatic changes in most of the parameters measured in this study, including an increase in serum amylase, and lowering the level of blood glucose, in comparison to the diabetic group. Conclusion: Daily administration of Rheum ribes significantly reduced blood glucose and caused a marked increase in the activity of Beta-cells, followed by a decrease in the activity of Alpha-cells. The results of tissue structures and serum biochemical estimation indicated that the plant extract has regeneration and repair effects.