Nitric oxide (NO) synthase inhibition increases hypertension and causes renal injury. Ferula gummosa is used in Iranian traditional medicine for treatment of several diseases and has been reported to exert a potent anti-inflammatory and antioxidant action. The aim of this investigation was to evaluate the renoprotective effects of hydroalcoholic extract of Ferula gummosa (HEG) on Nω-nitro-L-arginine methyl ester (L-NAME)-induced oxidative stress and inflammation and explore the mechanisms that link NO deficiency with altered renal heat shock protein (HSP70). Rats were injected intraperitoneally with L-NAME (10 mg/kg) to induce renal injury. Simultaneously, HEG (90 mg/kg) was administered by gastric gavage to L-NAME-treated rats for 6 days/week during an 8-week period. Renal thiobarbituric acid reactive substances (TBARS), superoxide dismutase (SOD), interleukin-6 (IL-6), tumor necrosis factor alpha (TNF-α), HSP70, plasma NO and total antioxidant capacity (TAC) were evaluated. The administration of L-NAME significantly increased renal TBARS, TNF-α, IL-6, HSP70 levels and decreased renal SOD activity, that these changes were accompanied by the reduced plasma NO and TAC levels. HEG administration decreased TBARS, HSP70, TNF-α and IL-6 levels and increased SOD activity in the kidney tissues of L-NAME treated rats (p<0.05). Also, plasma TAC level and NO bioavailability have been elevated after administration of HEG (p<0.05). These findings support that NO deficiency induces renal stress oxidative and inflammation, which markedly increased renal HSP70 and HEG could protect kidney against these damaging effects via its anti-oxidative, anti-inflammatory action and modulate renal HSP70.
Keywords: Antioxidant; nitric oxide; pro-inflammatory cytokines; stress protein.