title: Involvement of caspases in sympathetic neuron apoptosis.
abstract: In order to study the involvement of caspases in neuronal cell death, we have examined the effects of the viral caspase inhibitor p35 and peptide caspase inhibitors on sympathetic neurons isolated from the superior cervical ganglion (SCG). In these neurons, apoptosis can be induced by the withdrawal of nerve growth factor (NGF) and also by the addition of the kinase inhibitor staurosporine. p35 has been shown to be a broad spectrum inhibitor of the caspase family and promotes the survival of SCG neurons withdrawn from NGF. We show that p35 is also protective when apoptosis is induced by staurosporine. In addition, p35 inhibits a number of the morphological features associated with apoptosis, such as nuclear condensation, TUNEL labelling, and externalisation of phosphatidylserine. The tri-peptide caspase inhibitor benzyloxycarbonyl-Val-Ala-Asp (O-methyl)-fluoromethylketone (zVAD-fmk) was effective at inhibiting NGF withdrawal-induced and staurosporine-induced apoptosis of SCG neurons. Two other peptide inhibitors, acetyl-Tyr-Val-Ala-Asp-aldehyde (Ac-YVAD-CHO) and acetyl-Asp-Glu-Ala-Asp-aldehyde (Ac-DEVD-CHO), also inhibited apoptosis induced by both means when microinjected into SCG neurons but peptides derived from the caspase cleavage site in p35 were not protective. We present data to suggest that apoptosis induced by separate death stimuli can result either in the activation of distinct caspases or in differences in the time of activation of the family members.
authors.affiliation: Eisai London Research Laboratories Ltd., University College London, London WC1E 6BT, UK.
authors.forename: M J
authors.initials: MJ
authors.lastname: McCarthy
authors.forename: L L
authors.initials: LL
authors.lastname: Rubin
authors.forename: K L
authors.initials: KL
authors.lastname: Philpott
mesh_terms: D000818:Animals; D017304:Annexin A5 / Q000032:analysis; D017209:Apoptosis / Q000187:drug effects / Q000502:physiology*; D001710:Biotin; D029742:Caenorhabditis elegans Proteins; D020169:Caspases; D002462:Cell Membrane / Q000737:chemistry / Q000187:drug effects / Q000502:physiology; D002478:Cells, Cultured; D003546:Cysteine Endopeptidases / Q000378:metabolism*; D015853:Cysteine Proteinase Inhibitors / Q000494:pharmacology; D053938:DNA Fragmentation; D004791:Enzyme Inhibitors / Q000494:pharmacology; D009414:Nerve Growth Factors / Q000494:pharmacology; D009474:Neurons / Q000737:chemistry / Q000166:cytology* / Q000201:enzymology*; D010446:Peptide Fragments / Q000032:analysis; D051381:Rats; D013194:Staining and Labeling; D019311:Staurosporine / Q000494:pharmacology; D017783:Superior Cervical Ganglion / Q000166:cytology*; D014500:Uracil Nucleotides
chemical_list: D017304:Annexin A5; D029742:Caenorhabditis elegans Proteins; D015853:Cysteine Proteinase Inhibitors; D004791:Enzyme Inhibitors; D009414:Nerve Growth Factors; D010446:Peptide Fragments; D014500:Uracil Nucleotides; D001710:Biotin; D020169:Caspases; D003546:Cysteine Endopeptidases; C089223:ced-3 protein, C elegans; D019311:Staurosporine