Curcumin inhibits the proteinase-activated receptor-2-triggered prostaglandin E2 production by suppressing cyclooxygenase-2 upregulation and Akt-dependent activation of nuclear factor-κB in human lung epithelial cells

We performed this study to determine if curcumin affects pro-inflammatory responses to activation of proteinase-activated receptor-2 (par2) in human pulmonary adenocarcinoma a549 cells. curcumin completely inhibited the par2-triggered prostaglandin e2 (pge2) production,but notably not interleukin-8 release. cyclooxygenase-2 (cox-2) upregulation,but not its upstream activation of mitogen-activated protein kinases,caused by par2 stimulation was partially inhibited by curcumin. curcumin inhibited the par2-triggered phosphorylation of i-κb,an indicator for nuclear factor-κb (nf-κb) activation,and also its upstream signal akt,which is known to contribute to par2-triggered pge2 formation,but not cox-2 upregulation. collectively,curcumin inhibits the par2-triggered pge2 production by suppressing cox-2 upregulation and akt/nf-κb signals in a549 cells. © 2010 the japanese pharmacological society.