Evidence for the protective anti-inflammatory effects of IL-6 is derived from studies that show that endogenous IL-6 in endotoxin-induced ALI controls the level of pro-inflammatory cytokines and neutrophilic inflammation [24]; also, the administration of IL-6 induces SOD production and reduces LPS-induced neutrophilic infiltration in liver in a model of endotoxemia in rats [21]. This evidence concerns the gene SOD1 and serum lipopolysaccharide activity.