PTGS2 and colitis: It is reported that the andrographolide derivative AL-1 (andrographolide-lipoic acid conjugate) (5, 15 and 45 mg/kg) treatment can attenuate the expression levels of p-IκBα, p-p65 and cyclooxygenase-2 (COX2), and increase the expression of PPAR-γ, which contributes to reduction of colonic damage in TNBS-induced mice colitis [79].