A selective inhibitor of p38 MAP kinase, SB202190, induced apoptotic cell death of a lipopolysaccharide-treated macrophage-like cell line, J774.1.
A selective p38 MAP kinase (p38 MAPK) inhibitor, SB202190, induced apoptotic cell death of a macrophage-like cell line, J774.1, in the presence of lipopolysaccharide (LPS), as judged by DNA nicks revealed by terminal deoxy transferase (TdT)-mediated dUTP nick end labeling (TUNEL), activation of caspase-3, and subsequent release of lactate dehydrogenase. This cytotoxicity was dependent on both LPS and SB202190, and such inhibitors of the upstream LPS-signaling cascade as polymyxin B and TPCK blocked this macrophage cell death. SB202190 suppressed the kinase activity of p38, leading to inhibition of activation of MAPKAPK2 and then the subsequent phosphorylation of hsp27 in LPS-treated macrophages both in vitro and in vivo, but an inactive analog of SB202190, SB202474, did not. There was a threshold of the time of addition of SB202190 to LPS-treated macrophages to induce apoptosis, which was before full transmission of p38 activity to a direct downstream kinase, MAPKAPK2. Besides, localization of phosphorylated hsp27 in Golgi area of the LPS-treated macrophages was suppressed by SB202190, while it was not by SB202474. These results suggest that selective inhibition of p38 MAPK activity in LPS-induced MAP kinase cascade leads to apoptosis of macrophages.
Karahashi
H
H
Department of Biochemistry and Cell Biology, National Institute of Infectious Diseases, Tokyo, Japan.
Nagata
K
K
Ishii
K
K
Amano
F
F
D000595:Amino Acid Sequence; D000818:Animals; D017209:Apoptosis / Q000187:drug effects*; D053148:Caspase 3; D020169:Caspases / Q000378:metabolism; D002460:Cell Line; D004789:Enzyme Activation / Q000187:drug effects; D004791:Enzyme Inhibitors / Q000494:pharmacology*; D006360:Heat-Shock Proteins; D007093:Imidazoles / Q000494:pharmacology*; D020287:In Situ Nick-End Labeling; D008070:Lipopolysaccharides / Q000494:pharmacology; D008264:Macrophages / Q000166:cytology / Q000187:drug effects / Q000201:enzymology; D051379:Mice; D020928:Mitogen-Activated Protein Kinases / Q000037:antagonists & inhibitors* / Q000378:metabolism; D018832:Molecular Chaperones; D009363:Neoplasm Proteins / Q000737:chemistry / Q000378:metabolism; D010766:Phosphorylation; D011725:Pyridines / Q000494:pharmacology*; D015398:Signal Transduction; D048051:p38 Mitogen-Activated Protein Kinases
D004791:Enzyme Inhibitors; D006360:Heat-Shock Proteins; C486113:Hsbp1 protein, mouse; D007093:Imidazoles; D008070:Lipopolysaccharides; D018832:Molecular Chaperones; D009363:Neoplasm Proteins; D011725:Pyridines; D020928:Mitogen-Activated Protein Kinases; D048051:p38 Mitogen-Activated Protein Kinases; C505409:Casp3 protein, mouse; D053148:Caspase 3; D020169:Caspases; C090942:4-(4-fluorophenyl)-2-(4-hydroxyphenyl)-5-(4-pyridyl)imidazole