L-Arginine and L-glutamine as immunonutrients and modulating agents for oxidative stress and toxicity induced by sodium nitrite in rats

Sodium nitrite (NaNO2) is a flavoring, coloring and preservative agent in meat and fish products. The study aimed to evaluate the efficacy of L-arginine and L-glutamine supplementation as a potentially novel and useful strategy for the modulation of oxidative stress and toxicity induced by NaNO2 in male rats. Rats were divided into six groups each of 10 rats and treated for 6 weeks: group 1 as normal control; group 2 fed standard diet containing 0.2% NaNO2; group 3 and 4 fed the previous diet supplemented with 1% and 2% arginine, respectively; group 5 and 6 fed NaNO2 diet supplemented with 1% and 2% glutamine, respectively. NaNO2 treatment induced a significant increase in serum malondialdehyde, nitric oxide, arginase, glutathione-S-transferase activities, urea and creatinine as well as differential leucocytes%. However, a significant decrease was recorded in reduced glutathione, catalase activity, total protein, albumin and some hematological parameters as well as immunoglobulin G. On the other hand, arginine or glutamine showed a remarkable modulation of these abnormalities as indicated by reduction of malondialdehyde and improvement of the investigated antioxidant and hematological parameters. It can be concluded that arginine or glutamine supplementation may reduce oxidative stress and improve the hazard effects of NaNO2. (C) 2010 Elsevier Ltd. All rights reserved.