Introduction: Diabetes mellitus (DM), one of the major metabolic disorders, is characterized by high blood glucose levels due to the inability of body cells to utilize glucose properly. Diabetes is recognized for severe complications such as diabetic nephropathy, neuropathy, and retinopathy. The aim of the present study was to evaluate the protective role of the angiotensin receptor blocker; losartan potassium and the antioxidant; vitamin E against streptozotocin-induced diabetic nephropathy.
Material and Methods: forty male albino rats were divided into 5 groups each of 8. The 1st group acts as a healthy sham group and received citrate buffer. The 2nd group acts as an untreated diabetic group. The 3rd group acts as a diabetic group, treated with losartan potassium at dose 1mg/kg/day. The 4th group acts as a diabetic group received vitamin E at dose of 1gm/kg/day. The 5th group acts as a diabetic and received both losartan and vitamin E at the same doses used for 3rd and 4th groups respectively. Diabetes was induced by single intraperitoneal injection of streptozotocin (STZ) at 40mg/kg, and the treatment continued for 8 weeks. Serum glucose, triglycerides and total cholesterol as well as creatinine were measured at the end of the 8th week. Histochemical study, using H&E and PAS stains and immunohistochemical study of glomerular Cu,Zn-SOD were carried out.
Results:The rats of the diabetic non-treated group showed high serum glucose, triglycerides and cholesterol as well as creatinine levels and their kidney showed class II glomerulosclerosis with high score of the glomerular Cu,Zn SOD indicating oxidative renal damage. Treatments with losartan and/or vitamin E tend to normalize the studied parameters.
Conclusion: The pathogenesis of the diabetic nephropathy is mediated even partially through oxidative stress. Losartan potassium and vitamin E have a renoprotective effect against diabetic nephropathy. However, vitamin E had more protective effect than losartan and both had no additive renoprotective effects