TY - JOUR
T1 - Proapoptotic BCL-2 family members and mitochondrial dysfunction during ischemia/reperfusion injury, a study employing cardiac HL-1 cells and GFP biosensors
AU - Brady, Nathan R.
AU - Hamacher-Brady, Anne
AU - Gottlieb, Roberta A.
N1 - Funding Information:
HL-1 cells were kindly provided by Dr. William Claycomb (LSU Health Sciences Center, Louisiana). We would like to thank Dr. Richard Youle (National Institutes of Health, Maryland) for providing pEGFP-Bax, Dr. Roger Tsien (University of California, San Diego) for pRSET-mCherry, Professor Atsushi Miyawaki (Brain Science Institute, RIKEN, Japan), for Venus fluorescent protein, and Dr. David Piston (Vanderbilt University Medical Center, Tennessee ) for Cerulean CFP variant. We also thank Dr. Shixing Zhan (formerly of the Gottlieb lab) for the generation of BidΔcasp8 and are grateful to Dr. Chengqun Huang (Gottlieb lab) for helpful discussion of the p38 data. This work was supported by the NIH grants R01-AG21568 and R01-HL60590 (to R.A.G.) and the Stein endowment fund. This is MS #17963-MEM of The Scripps Research Institute.
PY - 2006/5
Y1 - 2006/5
N2 - The objective of this study was to evaluate mitochondrial alterations in a cell-based model of myocardial ischemia/reperfusion (I/R) injury. Using GFP-biosensors and fluorescence deconvolution microscopy, we investigated mitochondrial morphology in relation to Bax and Bid activation in the HL-1 cardiac cell line. Mitochondria underwent extensive fragmentation during ischemia. Bax translocation from cytosol to mitochondria was initiated during ischemia and proceeded during reperfusion. However, Bax translocation was not sufficient to induce cell death or mitochondrial dysfunction. Bid processing was caspase-8 dependent, and Bid translocation to mitochondria occurred after Bax translocation and clustering, and minutes before cell death. Clustering of Bax into distinct regions on mitochondria could be prevented by CsA, an inhibitor of the mitochondrial permeability transition pore, and also by SB203580, an inhibitor of p38 MAPK. Surprisingly, mitochondrial fragmentation which occurred during ischemia and before Bax translocation could be reversed by the addition of the p38 inhibitor SB203580 at reperfusion. Taken together, these results implicate p38 MAPK in the mitochondrial remodeling response to I/R that facilitates Bax recruitment to mitochondria.
AB - The objective of this study was to evaluate mitochondrial alterations in a cell-based model of myocardial ischemia/reperfusion (I/R) injury. Using GFP-biosensors and fluorescence deconvolution microscopy, we investigated mitochondrial morphology in relation to Bax and Bid activation in the HL-1 cardiac cell line. Mitochondria underwent extensive fragmentation during ischemia. Bax translocation from cytosol to mitochondria was initiated during ischemia and proceeded during reperfusion. However, Bax translocation was not sufficient to induce cell death or mitochondrial dysfunction. Bid processing was caspase-8 dependent, and Bid translocation to mitochondria occurred after Bax translocation and clustering, and minutes before cell death. Clustering of Bax into distinct regions on mitochondria could be prevented by CsA, an inhibitor of the mitochondrial permeability transition pore, and also by SB203580, an inhibitor of p38 MAPK. Surprisingly, mitochondrial fragmentation which occurred during ischemia and before Bax translocation could be reversed by the addition of the p38 inhibitor SB203580 at reperfusion. Taken together, these results implicate p38 MAPK in the mitochondrial remodeling response to I/R that facilitates Bax recruitment to mitochondria.
KW - Bax
KW - Bid
KW - Cell death
KW - Ischemia
KW - Mitochondria
KW - Reperfusion
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U2 - 10.1016/j.bbabio.2006.04.011
DO - 10.1016/j.bbabio.2006.04.011
M3 - Article
C2 - 16730326
AN - SCOPUS:33745628317
SN - 0005-2728
VL - 1757
SP - 667
EP - 678
JO - Biochimica et Biophysica Acta - Bioenergetics
JF - Biochimica et Biophysica Acta - Bioenergetics
IS - 5-6
ER -