Taurine chloramine inhibits prostaglandin E2 production in activated RAW 264.7 cells by post-transcriptional effects on inducible cyclooxygenase expression.
Taurine chloramine (Tau-Cl) was recently demonstrated to inhibit production of nitric oxide and tumor necrosis factor-alpha (TNF-alpha) by activated macrophages. Since increased production of prostaglandin E2 (PGE2), a reaction catalyzed by induction of cyclooxygenase-2 (COX-2), is also associated with the inflammatory response, we determined the effects of Tau-Cl on PGE2 production and on expression of COX-2 protein and COX-2 mRNA in activated RAW 264.7 cells, a murine macrophage-like cell line. Tau-Cl inhibited production of PGE2 in a concentration dependent manner with an IC50 of 0.4 mM. The decrease in PGE2 production was largely accounted for by decreased expression of COX-2 protein. Although the kinetics of COX-2 mRNA expression was altered in Tau-Cl treated cells, mRNA expression appeared to be quantitatively unimpaired. These results suggest that Tau-Cl affects the post-transcriptional regulation of COX-2 expression and support the idea that Tau-Cl may function as an inhibitory modulator of the inflammatory response.
Quinn
M R
MR
Department of Developmental Biochemistry, N.Y.S. Institute for Basic Research in Developmental Disabilities, Staten Island 10314, USA.
Park
E
E
Schuller-Levis
G
G
D000818:Animals; D002460:Cell Line; D051546:Cyclooxygenase 2; D015232:Dinoprostone / Q000096:biosynthesis*; D015971:Gene Expression Regulation, Enzymologic / Q000187:drug effects*; D007527:Isoenzymes / Q000235:genetics*; D008262:Macrophage Activation / Q000187:drug effects; D008264:Macrophages / Q000502:physiology*; D051379:Mice; D011451:Prostaglandin-Endoperoxide Synthases / Q000235:genetics*; D012333:RNA, Messenger / Q000235:genetics; D013654:Taurine / Q000031:analogs & derivatives* / Q000494:pharmacology
D007527:Isoenzymes; D012333:RNA, Messenger; D013654:Taurine; C043410:N-chlorotaurine; D051546:Cyclooxygenase 2; D011451:Prostaglandin-Endoperoxide Synthases; D015232:Dinoprostone