Anti-inflammatory and renal protective effect of gingerol in high-fat diet/streptozotocin-induced diabetic rats via inflammatory mechanism.

P38 mitogen-activated protein kinase (p38 MAPK), a tissue inflammatory factor can be activated under oxidative stress and in conditions associated with hyperglycemia. Gingerol containing various natural herbs has been extensively studied for its pharmacological actions both in reducing the inflammation and as immunity booster. The aim of the current investigation was to examine the renal protective effect of gingerol in high-fat diet/streptozotocin-induced type II diabetes mellitus in a rat model.NRK 52E cells were divided into normal and high glucose group treated with gingerol. The methylthiazotetrazolium assay was used to establish the cell proliferation progress. Streptozotocin-inducted diabetes in rats was treated with gingerol for 16 weeks. The blood glucose, serum creatinine, body weight, food intake, biochemical, antioxidant and haematological parameters were assayed to establish the correlation. Pro-inflammatory cytokines including Il-1β, IL-6, TNF-α; inflammatory mediator COX-2, PGE₂, NF-kB, p38MAPK, and TGF-β, were also determined to assess the molecular mechanism. Gingerol exhibited the protective effect on the high glucose level induced NRK 52E cells and did not show any effect on the normal cells. Gingerol significantly (P < 0.001) down-regulated the blood glucose level, creatinine and BUN level in a dose-dependent manner with further significantly (P < 0.001) alteration in pro-inflammatory cytokines, nuclear factor kappa B (N-κB) activation, renal p38MAPK, and TGF-β. From these studies it is possible to predict that gingerol plays a significant role in improving the condition of renal tissue by alteration in p38MAPK and NF-κB activity, and control inflammatory reaction and oxidative stress. Our investigation supports the clinical use of gingerol in future as an effective renal protective agent.