Early processing of Bid and caspase-6, -8, -10, -14 in the canine brain during cardiac arrest and resuscitation.
A clinically relevant model of transient global brain ischemia involving cardiac arrest followed by resuscitation in dogs was utilized to study the expression and proteolytic processing of apoptosis-regulatory proteins. In the hippocampus, an increase in pro-apoptotic Bcl-2 family proteins Bcl-XS and Bak was detected, concomitant with proteolysis of Bcl-XL and Bcl-2, following ischemia-reperfusion injury. Also, biphasic cleavage of Bid was found in this region of the brain, with early generation of tBid-p11 within 10 min of cardiac arrest, followed by generation of tBid-p15 within 30-min reperfusion, consistent with activation of this pro-apoptotic protein. In addition, cardiac arrest and resuscitation induced early, reperfusion-dependent proteolytic processing of pro-caspase-6, -8, -10, and -14, which preceded caspase-3 activation. Immunohistochemical analysis using antibodies, which preferentially recognize processed caspase-3, -6, -8, and -10, provided evidence of time-dependent activation of these proteases in both neurons and glia in ischemia-sensitive regions of the brain. In conclusion, extremely rapid, cell-selective processing of apoptosis-regulatory proteins occurs in a clinically relevant model of ischemic brain injury caused by cardiac arrest and resuscitation. The early cleavage of Bid and rapid depletion of 32-kDa pro-caspase-14 from the canine hippocampus after induction of ischemia suggests the involvement of calpains in the processing of these proteins. Demonstration of in vitro cleavage of recombinant mouse caspase-14 by calpain I in the present study lends support to this hypothesis, further implicating cross-talk between different protease families in the pathophysiology of ischemic neural cell death.
Krajewska
Maryla
M
The Burnham Institute, La Jolla, CA 92037, USA.
Rosenthal
Robert E
RE
Mikolajczyk
Jowita
J
Stennicke
Henning R
HR
Wiesenthal
Thomas
T
Mai
Juergen
J
Naito
Mikihiko
M
Salvesen
Guy S
GS
Reed
John C
JC
Fiskum
Gary
G
Krajewski
Stan
S
D000818:Animals; D017209:Apoptosis / Q000502:physiology*; D051023:BH3 Interacting Domain Death Agonist Protein; D002545:Brain Ischemia / Q000201:enzymology* / Q000503:physiopathology; D002154:Calpain / Q000378:metabolism; D002352:Carrier Proteins / Q000378:metabolism*; D053456:Caspase 14; D020169:Caspases / Q000378:metabolism*; D004195:Disease Models, Animal; D004285:Dogs; D005260:Female; D006324:Heart Arrest, Induced; D006624:Hippocampus / Q000201:enzymology* / Q000503:physiopathology; D008565:Membrane Proteins / Q000378:metabolism; D009410:Nerve Degeneration / Q000201:enzymology / Q000503:physiopathology; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000378:metabolism; D011930:Reaction Time / Q000502:physiology; D015427:Reperfusion Injury / Q000201:enzymology* / Q000503:physiopathology; D012151:Resuscitation; D050998:bcl-2 Homologous Antagonist-Killer Protein; D051020:bcl-X Protein
D051023:BH3 Interacting Domain Death Agonist Protein; D002352:Carrier Proteins; D008565:Membrane Proteins; D019253:Proto-Oncogene Proteins c-bcl-2; D050998:bcl-2 Homologous Antagonist-Killer Protein; D051020:bcl-X Protein; D002154:Calpain; C506449:Casp14 protein, mouse; D053456:Caspase 14; D020169:Caspases