Apoptosis in cerebellar granule neurones: involvement of interleukin-1 beta converting enzyme-like proteases.
Proteases of the interleukin-1 beta converting enzyme (ICE) family have been implicated as mediators of apoptosis in several cell types. Here we report the ability of peptide inhibitors of ICE-like proteases to inhibit apoptosis of cultured cerebellar granule neurones caused by reduction of extracellular K+ levels and by the broad-spectrum protein kinase inhibitor staurosporine. Unlike apoptosis induced by K+ deprivation, staurosporine-induced neuronal death does not require new protein synthesis. The ICE-like protease inhibitor benzyloxycarbonyl-Val-Ala-Asp (O-methyl)fluoromethyl ketone (zVAD-fmk) was found to be extremely effective at preventing staurosporine-induced death of cerebellar granule neurones and yet was completely ineffective in preventing K+ deprivation-induced death. Staurosporine induced cleavage of the 116-kDa poly (ADP-ribose) polymerase enzyme, a substrate of ICE-like proteases, to the 85-kDa product, and this cleavage was also blocked by zVAD. By comparison, K+ deprivation led to the disappearance of the 116-kDa protein, with no detectable increase in level of the 85-kDa cleavage product. Taken together, these results imply the existence of divergent ICE-like protease pathways in a CNS model of neuronal apoptosis.
Taylor
J
J
Eisai London Research Laboratories Ltd, University College London, England.
Gatchalian
C L
CL
Keen
G
G
Rubin
L L
LL
D000590:Amino Acid Chloromethyl Ketones / Q000494:pharmacology; D000818:Animals; D017209:Apoptosis / Q000502:physiology*; D020170:Caspase 1; D002478:Cells, Cultured / Q000166:cytology; D002531:Cerebellum / Q000166:cytology; D003546:Cysteine Endopeptidases / Q000378:metabolism*; D015853:Cysteine Proteinase Inhibitors / Q000494:pharmacology; D004791:Enzyme Inhibitors / Q000494:pharmacology; D007375:Interleukin-1 / Q000378:metabolism; D009474:Neurons / Q000166:cytology* / Q000201:enzymology*; D011065:Poly(ADP-ribose) Polymerases / Q000378:metabolism; D011188:Potassium / Q000494:pharmacology; D051381:Rats; D017207:Rats, Sprague-Dawley; D019311:Staurosporine / Q000494:pharmacology
D000590:Amino Acid Chloromethyl Ketones; D015853:Cysteine Proteinase Inhibitors; D004791:Enzyme Inhibitors; D007375:Interleukin-1; C096713:benzyloxycarbonylvalyl-alanyl-aspartyl fluoromethyl ketone; D011065:Poly(ADP-ribose) Polymerases; D003546:Cysteine Endopeptidases; D020170:Caspase 1; D019311:Staurosporine; D011188:Potassium