Effects of Oleuropein on renal antioxidant status and serum inflammatory factors in Streptozotocin-induced diabetic male rat

Intrarenal oxidative stress plays a critical role in the initiation and progression of diabetic kidney disease. Therefore, the aim of this study was to determine the effect of oleuropein on the activity of antioxidant enzymes of kidney tissue and anti-inflammatory factors in diabetic induced Streptozotocin male rats.

In this study, 28 adult male, Wistar rats, with a weight range of 190±30 gr, were randomly divided into 4 equal groups (n=7): control group, diabetic animals, treatment group and oleuropein group. Diabetes were induced in rats by a single injection of 60 mg / kg streptozotocin. Rats in the oleuropein and treatment groups received oleuropein at a daily dose of 60 mg / kg by gastric gavage for 30 days. At the end of the treatment, serum concentration of blood glucose, urea, Creatinine, IL-1, IL-6 and kidney tissue antioxidant including superoxide dismutase (SOD) glutathione peroxidase (GPX) enzymes activity, total antioxidant capacity (TAC) and Malondialdehyde level were measured.

The results revealed that serum level of blood glucose, urea, Creatinine, IL-1and IL-6 increased significantly in diabetic group compared with the control group (p˂0.001). In addition, TAC, SOD and GPX activity of kidney tissue increased and MDA level of kidney tissue decreased significantly in the treatment group compared with the diabetic group (p˂0.001).

The present study indicated that oral oleuropein can reduce blood glucose, oxidative stress and IL-1 and IL-6. These effects may be due to its ability in strengthening the antioxidant defense system.