Inhibitory effect of baicalin, baicalein and wogonin on secretory group IIA phospholipase A2.

Abstract

It is well known that the expression level of secretory group IIA phospholipase A2 (sPLA2-IIA) is elevated in inflammatory diseases and lipopolysaccharide (LPS) up-regulates the expression of sPLA2-IIA in human umbilical vein endothelial cells (HUVECs). Here, three structurally related polyphenols found in the Chinese herb Huang Qui, namely baicalin, baicalein, and wogonin, were examined for its effects on the expression and activity of sPLA2-IIA in HUVECs and mouse. Prior treatment of cells or mouse with baicalin, baicalein, and wogonin inhibited LPS-induced expression and activity of sPLA2-IIA. And each compound suppressed the activation of cytosolic phospholipase A2 (cPLA2) and extracellular signal-regulated kinase (ERK) 1/2 by LPS. Therefore, these results suggest that baicalin, baicalein, and wogonin inhibited LPS mediated expression of sPLA2-IIA by suppression of cPLA2 and ERK 1/2.