Background: Our study investigated the therapeutic role and potential mechanisms of pterostilbene (PS) in diabetic nephropathy (DN) rats. Methods: DN models were established by high-fat diet after streptozotocin injection. A total of 50 Sprague-Dawley rats were randomly divided into control, DN, PS-treated groups (PS-H, PS-M, PS-L). PS was administered to rats by gavage for 8 weeks at 3 different doses (25, 10, and 5 mg/kg/day). The levels of oxidative stress activity (superoxide dismutase [SOD], malondialdehyde [MDA], glutathione peroxidase [GSH-PX]) and inflammatory factors (tumor necrosis factor [TNF]-α, interleukin (IL)-6, IL-1β, monocyte chemoattractant factor [MCP]-1) were detected by ELISA. TGF-β, Smad1, and fibronectin (FN) were measured through immunohistochemistry. The relative expressions of phospho-IκBα/IκBα, phospho-IκB kinases (IKK)β/IKKβ, phospho-nuclear factor-κB (NF-κB) p65/NF-κB p65 were detected by western blot. Results: Compared with DN group, the levels of TNF-α, IL-6, IL-1β, and MCP-1 were decreased in the PS-H group (p < 0.05). Meanwhile, the levels of SOD, MDA, GSH-PX improved in kidney and serum in PS-H groups (p< 0.05). PS also significantly decreased the level of phospho-NF-κB p65 and increased the levels of phospho- IKKβ and phospho-Iκ-Bα (p < 0.05). The results showed that PS treatment decreased TGF-β, Smad1, and FN expressions. Conclusion: PS had potential therapeutic effects on DN, which may be related to the regulation of NF-κB pathway.
