IL6 and serum lipopolysaccharide activity: LPS-stimulated endotoxemia is mediated by Toll-like receptor-4 (TLR-4), which causes overwhelming production of tissue-damaging cytokines tumor necrosis factor-α (TNF-α), interleukin-1 (IL-1), and interleukin-6 (IL-6) and free radicals (Salomao et al., 2012; Van Amersfoort et al., 2003).