Involvement of mitogen-activated protein kinase homologues in the regulation of lipopolysaccharide-mediated induction of cyclo-oxygenase-2 but not nitric oxide synthase in RAW 264.7 macrophages.
In RAW 264.7 macrophages lipopolysaccharide (LPS) stimulated the activation of p42 and p44 MAP kinases and their upstream activator mitogen-activated protein (MAP) kinase kinase (MAPKK), and induced the 69-kDa isoform of cyclo-oxygenase-2 (COX-2) and the 130-kDa isoform of nitric oxide synthase (iNOS). PD 098059, a specific inhibitor of the activation of MAPKK, prevented LPS-mediated activation of MAPKK (IC50 = 3.0 +/- 0.1 microM, n = 3) and p42/44 MAP kinases and substantially reduced the induction of COX-2 by approximately 40%-70%, but was without effect upon the induction of iNOS. In parallel, LPS also stimulated the activation of p38 MAP kinase and the MAPKAP kinase-2, a downstream target of p38 MAP kinase. SB 203580, a specific inhibitor of p38 MAP kinase prevented the activation of p38 MAP kinase (IC50 = 3.3 +/- 1.4 microM, n = 3) and MAPKAP kinase-2 by LPS and reduced the induction of COX-2 by approximately 50-90%, with no significant effect upon iNOS expression. These studies indicate the involvement of both the classical p42/44 MAP kinases and p38 MAP kinase in the regulation of COX-2 but not iNOS induction following exposure to LPS.
Department of Physiology & Pharmacology, University of Strathclyde, Strathclyde Institute for Biomedical Sciences, Glasgow, UK. a.paul@strath.ac.uk
A
A
Paul
A
A
Cuenda
C E
CE
Bryant
J
J
Murray
E R
ER
Chilvers
P
P
Cohen
G W
GW
Gould
R
R
Plevin
D000818:Animals; D017871:Calcium-Calmodulin-Dependent Protein Kinases / Q000737:chemistry / Q000378:metabolism*; D002460:Cell Line; D051546:Cyclooxygenase 2; D004789:Enzyme Activation; D004790:Enzyme Induction; D047908:Intracellular Signaling Peptides and Proteins; D007527:Isoenzymes / Q000096:biosynthesis*; D008070:Lipopolysaccharides / Q000378:metabolism / Q000494:pharmacology; D008264:Macrophages / Q000187:drug effects / Q000201:enzymology*; D051379:Mice; D019950:Mitogen-Activated Protein Kinase 1 / Q000378:metabolism; D048052:Mitogen-Activated Protein Kinase 3; D020929:Mitogen-Activated Protein Kinase Kinases; D020928:Mitogen-Activated Protein Kinases; D019001:Nitric Oxide Synthase / Q000096:biosynthesis*; D052247:Nitric Oxide Synthase Type II; D011451:Prostaglandin-Endoperoxide Synthases / Q000096:biosynthesis*; D011494:Protein Kinases / Q000378:metabolism; D017346:Protein Serine-Threonine Kinases / Q000378:metabolism; D048051:p38 Mitogen-Activated Protein Kinases; D000099190:MAP-Kinase-Activated Kinase 2
D017871:Calcium-Calmodulin-Dependent Protein Kinases; D051546:Cyclooxygenase 2; D047908:Intracellular Signaling Peptides and Proteins; D007527:Isoenzymes; D008070:Lipopolysaccharides; D019950:Mitogen-Activated Protein Kinase 1; D048052:Mitogen-Activated Protein Kinase 3; D020929:Mitogen-Activated Protein Kinase Kinases; D020928:Mitogen-Activated Protein Kinases; D019001:Nitric Oxide Synthase; D052247:Nitric Oxide Synthase Type II; D011451:Prostaglandin-Endoperoxide Synthases; D011494:Protein Kinases; D017346:Protein Serine-Threonine Kinases; D048051:p38 Mitogen-Activated Protein Kinases; D000099190:MAP-Kinase-Activated Kinase 2; C496317:Nos2 protein, mouse