Flurbiprofen enantiomers inhibit inducible nitric oxide synthase expression in RAW 264.7 macrophages.
OBJECTIVE
Using RAW 264.7 macrophages, the present study investigates the influence of optically pure enantiomers of the nonsteroidal anti-inflammatory drug flurbiprofen on lipopolysaccharide (LPS)-induced inducible nitric oxide synthase (iNOS) expression.


METHODS
iNOS and cyclooxygenase-2 (COX-2) mRNA levels were measured by quantitative real-time reverse-transcription polymerase chain reaction (RT-PCR). Concentrations of nitrite (index of cellular NO production) and prostaglandin E2 (index of COX-2 activity) in cell culture supernatants were determined by Griess assay and enzyme immunoassay, respectively.


RESULTS
R(-)- and S(+)-flurbiprofen decreased LPS-induced iNOS mRNA and nitrite levels in an equipotent and concentration-dependent manner. Suppression of iNOS mRNA expression by R(-)- and S(+)-flurbiprofen was gene-specific in that both substances failed to inhibit LPS-induced COX-2 mRNA expression. By contrast, flurbiprofen enantiomers suppressed LPS-induced prostaglandin E2 formation enantioselectively with S(+)-flurbiprofen being considerably more potent than its R(-)-antipode.


CONCLUSIONS
Our results show that R(-)- and S(+)-flurbiprofen, albeit differing in their potency as inhibitors of COX-2 activity, equipotently suppress iNOS expression. Because sustained high NO levels are associated with pain and tissue injury under various pathological conditions, a suppression of the inducible NO pathway may contribute to the pharmacological action of both R(-)- and S(+)-flurbiprofen.
Hinz
B
B
Department of Experimental and Clinical Pharmacology and Toxicology, Friedrich Alexander University Erlangen-Nürnberg, Germany. hinz@pharmakologie.uni-erlangen.de
Brune
K
K
Rau
T
T
Pahl
A
A
D000818:Animals; D002460:Cell Line; D002470:Cell Survival / Q000187:drug effects; D016861:Cyclooxygenase Inhibitors / Q000737:chemistry / Q000494:pharmacology; D005480:Flurbiprofen / Q000737:chemistry / Q000494:pharmacology*; D015870:Gene Expression / Q000187:drug effects*; D008264:Macrophages / Q000187:drug effects* / Q000201:enzymology; D051379:Mice; D008968:Molecular Conformation; D019001:Nitric Oxide Synthase / Q000037:antagonists & inhibitors / Q000096:biosynthesis*; D052247:Nitric Oxide Synthase Type II
D016861:Cyclooxygenase Inhibitors; D005480:Flurbiprofen; D019001:Nitric Oxide Synthase; D052247:Nitric Oxide Synthase Type II; C496317:Nos2 protein, mouse