A new lectin from <i>Amanita vaginata</i> mushroom with potent anti-inflammatory activity

This study used 80% ammonium sulphate fractional precipitation, followed by affinity chromatography to purify a new lectin (AVL) from the crude extract of the <i>Amanita vaginata</i> mushroom. The purification procedure achieved a 20% yield, a specific activity of 5120 HU/mg protein, and a 16-fold increase in purity. SDS-PAGE analysis showed a single band of 45 kDa. We assessed AVL’s anti-inflammatory effect by measuring levels of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2), induced by lipopolysaccharide (LPS), in RAW 264.7 macrophages. Western blot analysis showed that iNOS and COX-2 protein levels were barely detectable in the control groups, but markedly elevated in the LPS-treated groups. However, AVL treatment significantly inhibited the expression of both iNOS and COX-2 in LPS-stimulated cells. This effect was dose-dependent. These findings suggest that AVL’s anti-inflammatory effects are mediated through the suppression of iNOS and COX-2 expression.