Abstract
Diabetic nephropathy (DN) is one of the most common chronic complications of diabetes, which is associated with an increased oxidative stress induced by hyperglycemia and alterations in DJ-1/NF-E2-related factor-2 (Nrf2) pathway. In the present study, we investigated the role and the proper time nodes of DJ-1/Nrf2 pathway in the pathogenesis of DN. Diabetes mellitus (DM) model of rats was induced by intraperitoneal injection of streptozotocin (STZ) on male Sprague-Dawley (SD) rats. Then, the diabetic rats were divided into 4, 8 and 12 weeks groups. As early at 4 weeks of diabetes, renal histologic evaluation score, cystatin C (Cys C), β2-microglobulin (β2-MG) and malondialdehyde (MDA) levels were increased, and total antioxidative capacity (T-AOC) level was decreased as compared with that in the control group. The protein expressions of DJ-1, NF-E2-related factor-2 (Nrf2) and heme oxygenase-1 (HO-1) were upregulated compared with the control group from 4 weeks and further increased with the progression of DM. The protein expressions of DJ-1, Nrf2 and HO-1 in renal tissues have good line correlations with renal histologic evaluation score, respectively. Taken together, these results suggested that the activation of DJ-1/Nrf2 pathway was involved in the pathogenesis of diabetic nephropathy in rats.