Updated in 3/17/2010 6:41:09 PM      Viewed: 161 times      (Journal Article)
The Journal of biological chemistry 276 (33): 30724-8 (2001)

Bid is cleaved by calpain to an active fragment in vitro and during myocardial ischemia/reperfusion.

M Chen , H He , S Zhan , S Krajewski , J C Reed , R A Gottlieb
ABSTRACT
Reperfusion after myocardial ischemia is associated with a rapid influx of calcium, leading to activation of various enzymes including calpain. Isolated perfused adult rabbit hearts subjected to global ischemia and reperfusion were studied. Calpain or a calpain-like activity was activated within 15 min after reperfusion, and preconditioning suppressed calpain activation. In contrast, caspase activation was not detected although cytochrome c was released after ischemia and reperfusion. The pro-apoptotic BH3-only Bcl-2 family member, Bid, was cleaved during ischemia/reperfusion in the adult rabbit heart. Recombinant Bid was cleaved by calpain to a fragment that was able to mediate cytochrome c release. The calpain cleavage site was mapped to a region within Bid that is extremely susceptible to proteolysis. These findings suggest that there is cross-talk between apoptotic and necrotic pathways in myocardial ischemia/reperfusion injury.
DOI: 10.1074/jbc.M103701200      ISSN: 0021-9258