Histopathological, immunohistochemical and biochemical investigation of antidiabetic effect of juniper (juniperus communis l.) oil in diabetic rats

In this study, antidiabetic effect of juniper (Juniper berry; JB) oil in streptozotocin (STZ) induced diabetic rat model was investigated histopathologically, immunohistochemically and biochemically. For this purpose, 40 male Wistar albino rats were divided into five group, namely, control, diabetes mellitus (DM), DM + acarbose, DM + JB and JB groups. Experimental diabetes was established by injecting the rats with a single dose (55 mg/kg) of STZ intraperitoneally. The rats in the DM + JB and JB groups received 50 ml JB oil/kg diet. After 28 days, the rats were sacrificed and blood and tissue samples were obtained. Tissue samples were stained with Hematoxylin & Eosin (H&E) and histopathological examination was performed. Immunohistochemically, insulin immuno-expression was studied in pancreatic tissue. ALT, AST, ALP, LDH, total cholesterol, triglyceride, creatinine, and urea levels were investigated in serum. Histopathologically, degeneration of hepatocytes in liver, degeneration and necrosis of tubular cells and deterioration of glomerular structure in kidneys were seen in DM group rats. The normal appearance of islets of the langerhans were impaired as a result of significant cell loss. These histopathological changes were significantly reduced in DM + JB group. Immunohistochemically, there was a decrease in the number of insulin immunoreactive cells in the DM group due to the STZ-induced degenerative changes in beta (β) cells. A significant increase in the number of immunoreactive β cells was determined by treatment with JB oil. Biochemical results showed significant improvement in ALT, AST, urea and creatinine levels as a result of JB oil treatment, while significant decrease in blood glucose level was determined. These results indicate that JB oil has protective effect against STZ-induced diabetes in rats.