Abstract T P79: Rapamycin Improves Outcome Post Stroke Injury by Enhancing Autophagy in Neuronal Cells
Background and Purpose: Previous literature and studies from our laboratory indicate that pharmacological inhibition and enhancement of autophagy are both effective in reducing infarct volume after stroke injury.
Methods: Mice were treated with rapamycin to enhance, and chloroquine to suppress autophagy in mice immediately after stroke injury and again 24 hours post stroke injury in a murine stroke model. Survival data and neurological score were taken before sacrifice at 48 hours and lesion size was determined by TTC. HT22 neuronal mouse hippocampal cells were treated for one hour with H2O2 to mimic an oxidative stress injury and treated concurrently with rapamycin to enhance autophagy, chloroquine to inhibit autophagy or ZVAD to inhibit apoptosis. The treatment with pharmacological agents continued for 24 hours. Cells were counted with trypan blue on a hemocytometer. Western blot analysis was used to monitor protein changes. shRNA to Atg5 was used to genetically inhibit autophagy.
Results: Both pharmacological agents showed decreased lesion size, though enhancement of autophagy with rapamycin exhibited a greater reduction in lesion size as well as increased survival and an improved neurological score. Rapamycin improved survival of neurons after oxidative injury and genetic inhibition of autophagy abrogated rapamycin's positive effect.
Conclusions: Rapamycin improves stroke outcome by enhancing autophagy in neuronal cells.
Author Disclosures: K.M. Buckley: None. M.N. Hoda: None. G. Kondrikova: None. I.Y. Sazonova: None. D.C. Hess: None. P.V. Schoenlein: None. W.D. Hill: None.
- © 2015 by American Heart Association, Inc.