Synergetic activation of p38 mitogen-activated protein kinase and caspase-3-like proteases for execution of calyculin A-induced apoptosis but not N-methyl-d-aspartate-induced necrosis in mouse cortical neurons.
We examined the possibility that p38 mitogen-activated protein kinase and caspase-3 would be activated for execution of apoptosis and excitotoxicity, the two major types of neuronal death underlying hypoxicischemic and neurodegenerative diseases. Mouse cortical cell cultures underwent widespread neuronal apoptosis 24 h following exposure to 10-30 nM calyculin A, a selective inhibitor of Ser/Thr phosphatase I and IIA. Activity of p38 was increased 2-4 h following exposure to 30 nM calyculin A. Addition of 3-10 microM PD169316, a selective p38 inhibitor, partially attenuated calyculin A neurotoxicity. Activity of caspase-3-like proteases was increased in cortical cell cultures exposed to 30 nM calyculin A for 8-16 h as shown by cleavage of DEVD-p-nitroanilide and phosphorylated tau. Proteolysis of tau was completely blocked by addition of 100 microM N-benzyloxycarbonyl-Val-Ala-Asp-fluoromethyl ketone (z-VAD-fmk), a broad-spectrum inhibitor of caspases, but incompletely by 10 microM PD169316. Calyculin A neurotoxicity was partially sensitive to 100 microM z-VAD-fmk. Cotreatment with 10 microM PD169316 and 100 microM z-VAD-fmk showed additive neuroprotection against calyculin A. Neither PD169316 nor z-VAD-fmk showed a beneficial effect against excitotoxic neuronal necrosis induced by exposure to 20 microM NMDA. Thus, caspase-3-like proteases and p38 likely contribute to calyculin A-induced neuronal apoptosis but not NMDA-induced neuronal necrosis.
Ko
H W
HW
Department of Pharmacology Ajou University School of Medicine, Suwon, Kyungkido, Korea.
Han
K S
KS
Kim
E Y
EY
Ryu
B R
BR
Yoon
W J
WJ
Jung
Y K
YK
Kim
S U
SU
Gwag
B J
BJ
D000590:Amino Acid Chloromethyl Ketones / Q000494:pharmacology; D000818:Animals; D017209:Apoptosis / Q000187:drug effects / Q000502:physiology*; D053148:Caspase 3; D020169:Caspases / Q000378:metabolism*; D002478:Cells, Cultured; D002540:Cerebral Cortex / Q000166:cytology; D015853:Cysteine Proteinase Inhibitors / Q000494:pharmacology; D004357:Drug Synergism; D004791:Enzyme Inhibitors / Q000494:pharmacology; D018690:Excitatory Amino Acid Agonists / Q000494:pharmacology*; D005333:Fetus / Q000166:cytology; D007093:Imidazoles / Q000494:pharmacology; D008387:Marine Toxins; D051379:Mice; D020928:Mitogen-Activated Protein Kinases / Q000037:antagonists & inhibitors / Q000378:metabolism*; D016202:N-Methylaspartate / Q000494:pharmacology*; D009336:Necrosis; D009474:Neurons / Q000737:chemistry / Q000201:enzymology* / Q000473:pathology; D009498:Neurotoxins / Q000494:pharmacology; D010080:Oxazoles / Q000494:pharmacology*; D016194:Receptors, N-Methyl-D-Aspartate / Q000502:physiology; D048051:p38 Mitogen-Activated Protein Kinases; D016875:tau Proteins / Q000378:metabolism
D000590:Amino Acid Chloromethyl Ketones; D015853:Cysteine Proteinase Inhibitors; D004791:Enzyme Inhibitors; D018690:Excitatory Amino Acid Agonists; D007093:Imidazoles; D008387:Marine Toxins; D009498:Neurotoxins; D010080:Oxazoles; D016194:Receptors, N-Methyl-D-Aspartate; C096713:benzyloxycarbonylvalyl-alanyl-aspartyl fluoromethyl ketone; D016875:tau Proteins; D016202:N-Methylaspartate; C059041:calyculin A; D020928:Mitogen-Activated Protein Kinases; D048051:p38 Mitogen-Activated Protein Kinases; C505409:Casp3 protein, mouse; D053148:Caspase 3; D020169:Caspases; C408604:2-(4-nitrophenyl)-4-(4-fluorophenyl)-5-(4-pyridinyl)-1H-imidazole