Glucosamine inhibits LPS-induced COX-2 and iNOS expression in mouse macrophage cells (RAW 264.7) by inhibition of p38-MAP kinase and transcription factor NF-kappaB.
Glucosamine supplements are very promising nonsteroidal anti-inflammatory agents widely used for the treatment of arthritis in animals and humans. In this study, we have proposed the molecular mechanism underlying the anti-inflammatory properties of glucosamine hydrochloride (GLN) using mouse macrophage cell line (RAW 264.7). Treatment with GLN inhibited LPS-stimulated nitric oxide (NO) production. Western blotting and RT-PCR analysis showed that GLN treatment decreased LPS-induced inducible nitric-oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) protein and mRNA expression in RAW 264.7 cells, respectively. To further elucidate the mechanism of inhibitory effect of GLN, we studied the LPS-induced phosphorylation of mitogen-activated protein kinases (pp44/42 and pp38). Our results clearly indicated that GLN treatment resulted in a reduction of pp38, whereas activation of p44/42 was not affected. In addition, LPS-induced activation of nuclear factor-kappaB (NF-kappaB) DNA binding suggests an inhibitory effect of GLN. These results indicate that GLN suppresses the LPS-induced production of NO, expression of iNOS and COX-2 by inhibiting NF-kappaB activation and phosphorylation of p38 MAP kinase.
Rafi
Mohamed M
MM
Department of Food Science, Cook College, Rutgers, The State University of New Jersey, New Brunswick, New Jersey 08901, USA. rafi@rci.rutgers.edu
Yadav
Prem N
PN
Rossi
Andrea O
AO
D000818:Animals; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000494:pharmacology; D002460:Cell Line; D051546:Cyclooxygenase 2 / Q000235:genetics / Q000378:metabolism*; D052246:Cyclooxygenase 2 Inhibitors / Q000494:pharmacology; D004791:Enzyme Inhibitors / Q000494:pharmacology; D015870:Gene Expression / Q000187:drug effects; D005944:Glucosamine / Q000494:pharmacology*; D008070:Lipopolysaccharides / Q000494:pharmacology*; D008264:Macrophages / Q000201:enzymology; D051379:Mice; D016328:NF-kappa B / Q000037:antagonists & inhibitors*; D009569:Nitric Oxide / Q000378:metabolism; D052247:Nitric Oxide Synthase Type II / Q000037:antagonists & inhibitors* / Q000235:genetics; D010766:Phosphorylation / Q000187:drug effects; D012333:RNA, Messenger / Q000032:analysis; D048051:p38 Mitogen-Activated Protein Kinases / Q000037:antagonists & inhibitors*
D000894:Anti-Inflammatory Agents, Non-Steroidal; D052246:Cyclooxygenase 2 Inhibitors; D004791:Enzyme Inhibitors; D008070:Lipopolysaccharides; D016328:NF-kappa B; D012333:RNA, Messenger; D009569:Nitric Oxide; D052247:Nitric Oxide Synthase Type II; D051546:Cyclooxygenase 2; D048051:p38 Mitogen-Activated Protein Kinases; D005944:Glucosamine