Protective Effect of Royal Jelly against Renal Damage in Streptozotocin Induced Diabetic Rats

Royal jelly has been shown to have antioxidant and antidiabetic effects. The objective of this study was to evaluate the protective effect of RJ against kidney damage in streptozotocin induced diabetic rats. Thirty two male Wistar rats were divided randomly into four groups (n=8 per group). Normal control and diabetic control groups received 1cc/day distilled water, normal RJ-treated and diabetic RJ-treated groups received 100mg RJ/kg body weight daily. Diabetes was induced by intraperitoneal injection of streptozotocin. At the end of the experiment, urine and kidney samples were collected for biochemical and histopathological analysis. The results showed that diabetes could increase levels of urine urea, total protein and albumin significantly, and could decrease the levels of creatinine and uric acid in urine. In the kidney tissue homogenates, catalase activity and antioxidant power were significantly lower, whereas malondialdehyde levels were significantly higher in diabetic group when compared with control group. Diabetic rats showed severe histological changes in kidney tissues. Treatment of diabetic rats with RJ improved significantly all of these parameters. The present study revealed that treatment with RJ resulted in significant improvement in histopathological alterations in kidney tissue and urine parameters of diabetic rats. This could be due to its antioxidant activity and the ability of RJ for scavenging the free radicals released in diabetes. These findings suggest that RJ has protective effects on kidneys affected by diabetes mellitus.