1. Bcl-2 overexpression protects against neuron loss within the ischemic margin following experimental stroke and inhibits cytochrome c translocation and caspase-3 activity
- Author
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Midori A. Yenari, Danye Cheng, Robert M. Sapolsky, Heng Zhao, and Gary K. Steinberg
- Subjects
Pathology ,medicine.medical_specialty ,Programmed cell death ,Necrosis ,biology ,business.industry ,Penumbra ,Cytochrome c ,Ischemia ,Caspase 3 ,medicine.disease ,Biochemistry ,Cellular and Molecular Neuroscience ,Bcl-2-associated X protein ,Apoptosis ,Cancer research ,biology.protein ,Medicine ,cardiovascular diseases ,medicine.symptom ,business - Abstract
Bcl-2 protects against both apoptotic and necrotic death induced by several cerebral insults. We and others have previously demonstrated that defective herpes simplex virus vectors expressing Bcl-2 protect against various insults in vitro and in vivo, including cerebral ischemia. Because the infarct margin may be a region that is most amenable to treatment, we first determined whether gene transfer to the infarct margin is possible using a focal ischemia model. Since ischemic injury with and without reperfusion may occur by different mechanisms, we also determined whether Bcl-2 protects against focal cerebral ischemic injury either with or without reperfusion in rats. Bax expression, cytochrome c translocation and activated caspase-3 expression were also assessed. Viral vectors overexpressing Bcl-2 were delivered to the infarct margin. Reperfusion resulted in larger infarcts than permanent occlusion. Bcl-2 overexpression significantly improved neuron survival in both ischemia models. Bcl-2 overexpression did not alter overall Bax expression, but inhibited cytosolic accumulation of cytochrome c and caspase-3 activation. Thus, we provide the first evidence that gene transfer to the infarct margin is feasible, that overexpression of Bcl-2 protects against damage to the infarct margin induced by ischemia with and without reperfusion, and that Bcl-2 overexpression using gene therapy attenuates apoptosis-related proteins. This suggests a potential therapeutic strategy for stroke.
- Published
- 2003
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