Upstream control of apoptosis by caspase-2 in serum-deprived primary neurons.
During development as well as in pathological situations, neurons that fail to find appropriate targets or neurotrophic factors undergo cell death. Using primary cortical neurons subjected to acute serum-deprivation (SD), we have examined caspases activation, mitochondrial dysfunction and cell death parameters. Among a panel of metabolic, signaling and caspases inhibitors only those able to interfere with caspase-2 like activity protect primary neurons against SD-induced cell death. In situ detection and subcellular fractionation demonstrate a very early activation of cytosolic caspase-2, which controls Bax cleavage, relocalization and mitochondrial membrane permeabilization (MMP). Both z-VDVAD-fmk and a siRNA specific for caspase-2 abolish Bax changes, mitochondrial membranes permeabilization, as well as cytochrome c release-dependent activation of caspase-9/caspase-3, nuclear alterations, phosphatidylserine exposure, neurites dismantling and neuronal death. Hence, caspase-2 is an early checkpoint for apoptosis initiation in primary neurons subjected to serum deprivation.
Chauvier
D
D
Theraptosis Research Laboratory, Theraptosis S.A., Pasteur Biotop, Institut Pasteur, 25-28 Rue du Docteur Roux, 75015 Paris, France. dchauvier@theraptosis.com
Lecoeur
H
H
Langonné
A
A
Borgne-Sanchez
A
A
Mariani
J
J
Martinou
J-C
JC
Rebouillat
D
D
Jacotot
E
E
D000818:Animals; D017209:Apoptosis / Q000187:drug effects; D053143:Caspase 2 / Q000172:deficiency / Q000378:metabolism*; D002470:Cell Survival / Q000187:drug effects; D002478:Cells, Cultured; D045304:Cytochromes c / Q000378:metabolism; D004789:Enzyme Activation / Q000187:drug effects; D004791:Enzyme Inhibitors / Q000494:pharmacology; D006801:Humans; D051379:Mice; D008928:Mitochondria / Q000187:drug effects / Q000201:enzymology / Q000378:metabolism; D008954:Models, Biological; D009474:Neurons / Q000166:cytology* / Q000187:drug effects / Q000201:enzymology*; D010455:Peptides / Q000494:pharmacology; D021381:Protein Transport / Q000187:drug effects; D034622:RNA Interference; D044967:Serum; D051028:bcl-2-Associated X Protein / Q000378:metabolism
D004791:Enzyme Inhibitors; D010455:Peptides; D051028:bcl-2-Associated X Protein; D045304:Cytochromes c; D053143:Caspase 2