Mild Postischemic Hypothermia Prolongs the Time Window for Gene Therapy by Inhibiting Cytochrome c Release

H Zhao, MA Yenari, RM Sapolsky, GK Steinberg - Stroke, 2004 - Am Heart Assoc
H Zhao, MA Yenari, RM Sapolsky, GK Steinberg
Stroke, 2004Am Heart Assoc
Background and Purpose—We showed previously that Bcl-2 overexpression with the use of
herpes simplex viral (HSV) vectors improved striatal neuron survival when delivered 1.5
hours after stroke but not when delivered 5 hours after stroke onset. Here we determine
whether hypothermia prolongs the therapeutic window for gene therapy. Methods—Rats
were subjected to focal ischemia for 1 hour. Hypothermia (33° C) was induced 2 hours after
insult and maintained for 3 hours. Five hours after ischemia onset, HSV vectors expressing …
Background and Purpose— We showed previously that Bcl-2 overexpression with the use of herpes simplex viral (HSV) vectors improved striatal neuron survival when delivered 1.5 hours after stroke but not when delivered 5 hours after stroke onset. Here we determine whether hypothermia prolongs the therapeutic window for gene therapy.
Methods— Rats were subjected to focal ischemia for 1 hour. Hypothermia (33°C) was induced 2 hours after insult and maintained for 3 hours. Five hours after ischemia onset, HSV vectors expressing Bcl-2 plus β-gal or β-gal alone were injected into each striatum. Rats were killed 2 days later.
Results— Striatal neuron survival of Bcl-2–treated, hypothermic animals was improved 2- to 3-fold over control-treated, hypothermic animals and Bcl-2–treated, normothermic animals. Neuron survival among normothermic, Bcl-2–treated animals was not different from control normothermics or control hypothermics. Double immunostaining of cytochrome c and β-gal demonstrated that Bcl-2 plus hypothermia significantly reduced cytochrome c release.
Conclusions— Postischemic mild hypothermia extended the time window for gene therapy neuroprotection using Bcl-2 and reduced cytochrome c release.
Am Heart Assoc