The acai flavonoid velutin is a potent anti-inflammatory agent: blockade of LPS-mediated TNF-α and IL-6 production through inhibiting NF-κB activation and MAPK pathway

Recent studies have shown that some flavonoids are modulators of proinflammatory cytokine production. In this study, velutin, a unique flavone isolated from the pulp of acai fruit (Euterpe oleracea Mart.), was examined for its effects in reducing lipopolysaccharide-induced proinflammatory cytokine tumor necrosis factor (TNF)-alpha and interleukin (IL)-6 production in RAW 264.7 peripheral macrophages and mice peritoneal macrophages. Three other structurally similar and well-studied flavones, luteolin, apigenin and chrysoeriol, were included as controls and for comparative purposes. Velutin exhibited the greatest potency among all flavones in reducing TNF-alpha and IL-6 production. Velutin also showed the strongest inhibitory effect in nuclear factor (NF)-kappa B activation (as assessed by secreted alkaline phosphatase reporter assay) and exhibited the greatest effects in blocking the degradation of inhibitor of NF-kappa B as well as in inhibiting mitogen-activated protein kinase p38 and JNK phosphorylation; all of these are important signaling pathways involved in production of INF-a and IL-6. The present study led to the discovery of a strong anti-inflammatory flavone, velutin. This compound effectively inhibited the expression of proinflammatory cytokines TNF-alpha and IL-6 in low micromole levels by inhibiting NF-kappa B activation and p38 and JNK phosphorylation. (C) 2012 Elsevier Inc. All rights reserved.