Arginine-supplemented diets improve survival in gutderived sepsis and peritonitis by modulating bacterial clearance: the role of nitric oxide Gianotti L, Alexander J W, Pyle T, and Fukushima R. Ann Surg 1993; 217: 644-654.
The effects of arginine on survival rates and host defence mechanisms were studied using two models of infection that included allogeneic transfusion-induced immunosuppression. Mice were fed for 10 days with chow, or a semi-purified commercial diet (AIN-76A), which was either unsupplemented or supplemented with arginine (2%; test diet) or glycine. After allogeneic blood transfusions and feeding for a further 5 days, the mice were subjected to caecal ligation and puncture (CLP), or 20% burn injury plus gavage with 10(10), (14)C-radiolabelled E. coli. Survival rate after CLP (AIN-76A diets) was 56% in the arginine supplemented group (AIN-76A) versus 28% in the AIN-76A unsupplemented group and 20% in the animals fed chow (P 0.02). After burn injury and gavage survival was 100% in the arginine-supplemented group versus 50% in both the chow and AIN-76A glycine supplemented group, and 35% in the AIN-76A unsupplemented group (P 0.01). Quantitative colony counts and % viable bacteria remaining in mesenteric lymph nodes, liver, and spleen suggested that the ability to kill translocated bacteria was significantly enhanced in animals receiving arginine. Treatment with the nitric oxide inhibitor, Nw-Nitro-L-arginine, reversed the beneficial effects or arginine. It is concluded that the benefit of arginine appears to be mediated by improved bactericidal mechanisms via the arginine nitric-oxide pathway.
Elia
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MRC Dunn Clinical Nutrition Centre, Hills Road, Cambridge, CB2 1QL, UK.