Analysis of Inhibitory Effects of Scutellariae Radix and Baicalein on Prostaglandin E2Production in Rat C6 Glioma Cells

Abstract

Inhibitory mechanism of the water extract of Scutellariae Radix on prostaglandin E2(PGE2) release was examined in C6 rat glioma cells. Scutellariae Radix reduced a Ca2+ionophore A23l87-induced PGE2release by inhibition of arachidonic acid (AA) liberation. Sho-saiko-to and San'o-shashin-to, which contain Scutellariae Radix, also inhibited PGE2release. A23l87 caused phospho-rylation of mitogen-activated protein kinase (MAPK), resulting in activation of cytosolic phospholipase A2(cPLA2). Scutellariae Radix and baicalein inhibited the phosphorylation of MAPK. Baicalein, but not baicalin, inhibited A23l87-induced PGE2release. These results suggest that baicalein in Scutellariae Radix reduces AA liberation through the inhibition of the MAPK-cPLA2pathway.