title: Evidence for activation of caspase-3-like protease in excitotoxin- and hypoxia/hypoglycemia-injured neurons.
abstract: Caspase activation has been shown to be a critical step in several models of neuronal apoptosis such as staurosporine treatment of human neuroblastoma SH-SY5Y cells and potassium deprivation of rat cerebellar granule neurons. One common event is the appearance of caspase-mediated 120-kDa nonerythroid alpha-spectrin breakdown product (SBDP120). Second, inhibitors of the caspase family are effective blockers of such neuronal death. In this study, we report the appearance of caspase-mediated SBDP120 in excitotoxin-challenged fetal rat cerebrocortical neurons [N-methyl-D-aspartate (NMDA), alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid, and kainate] and rat cerebellar granule neurons (NMDA and kainate). A general caspase inhibitor, carbobenzoxy-Asp-CH2OC(O)-2,6-dichlorobenzene (Z-D-DCB), blocked the formation of SBDP120 under these conditions and attenuated the observed NMDA-induced lactate dehydrogenase (LDH) release in both cell types. Furthermore, hydrolytic activity toward a caspase-3-preferred synthetic peptide substrate, acetyl-DEVD-7-amido-4-methylcoumarin, was significantly elevated in NMDA-treated granule neurons. Lastly, oxygen-glucose deprivation (OGD)-challenged cerebrocortical cultures also showed the appearance of SBDP120. Again, Z-D-DCB blocked the SBDP120 formation as well as attenuated the LDH release from the OGD-challenged neurons. Taken together, the presence of caspase-specific SBDP120 and the neuroprotective effects of Z-D-DCB strongly suggest that caspase activation contributes at least in part to excitotoxin- and OGD-induced neuronal death.
authors.affiliation: Department of Neuroscience Therapeutics, Parke-Davis Pharmaceutical Research, Warner-Lambert Company, Ann Arbor, Michigan 48105, USA.
authors.forename: R
authors.initials: R
authors.lastname: Nath
authors.forename: A
authors.initials: A
authors.lastname: Probert
authors.forename: K M
authors.initials: KM
authors.lastname: McGinnis
authors.forename: K K
authors.initials: KK
authors.lastname: Wang
mesh_terms: D000818:Animals; D053148:Caspase 3; D020169:Caspases; D016923:Cell Death / Q000187:drug effects / Q000502:physiology; D015687:Cell Hypoxia / Q000502:physiology; D002478:Cells, Cultured; D002531:Cerebellum / Q000166:cytology; D002540:Cerebral Cortex / Q000166:cytology; D003546:Cysteine Endopeptidases / Q000378:metabolism*; D004792:Enzyme Precursors / Q000378:metabolism; D018690:Excitatory Amino Acid Agonists / Q000494:pharmacology; D005333:Fetus / Q000166:cytology; D005947:Glucose / Q000494:pharmacology; D007003:Hypoglycemia / Q000378:metabolism; D007608:Kainic Acid / Q000494:pharmacology; D016202:N-Methylaspartate / Q000494:pharmacology; D009474:Neurons / Q000166:cytology / Q000187:drug effects / Q000201:enzymology*; D009498:Neurotoxins / Q000494:pharmacology*; D009842:Oligopeptides / Q000494:pharmacology; D010446:Peptide Fragments / Q000032:analysis; D011480:Protease Inhibitors / Q000494:pharmacology; D051381:Rats; D017207:Rats, Sprague-Dawley; D013049:Spectrin / Q000378:metabolism
chemical_list: D004792:Enzyme Precursors; D018690:Excitatory Amino Acid Agonists; D009498:Neurotoxins; D009842:Oligopeptides; D010446:Peptide Fragments; D011480:Protease Inhibitors; C105042:benzyloxycarbonyl-Glu-Val-Asp-CH2OC(O)-2,6-dichlorobenzene; D013049:Spectrin; D016202:N-Methylaspartate; C505407:CASP3 protein, human; C505410:Casp3 protein, rat; D053148:Caspase 3; D020169:Caspases; D003546:Cysteine Endopeptidases; D005947:Glucose; D007608:Kainic Acid