1a,1b-dihomo Prostaglandin E2 (PGE2) is a rare polyunsaturated fatty acid first identified in extracts of sheep vesicular gland microsomes, known to contain COX, incubated with adrenic acid . 1a,1b-dihomo PGE2 has also been identified in conditioned media of RAW 264.7 macrophages stimulated with endotoxin and arachidonic acid . This product is thought to be produced by elongation of AA to adrenic acid, which is then metabolized sequentially by COX and PGEsynthase.
AF3442 is a potent and selective mPGES-1 inhibitor (microsomal prostaglandin (PG) E synthase-1). AF3442 caused a concentration-dependent inhibition of PGE(2) in human recombinant mPGES-1 with an IC(50) of 0.06microM. AF3442 is a selective mPGES-1 inhibitor which reduced monocyte PGE(2) generation also in the presence of plasma proteins. Pharmacological inhibition of mPGES-1 did not translate into redirection of PGH(2) metabolism towards other terminal PG synthases in monocytes. The functional relevance of this observation deserves to be investigated in vivo.