Abstract 90: Diabetes Impairs Post-stroke Cerebrovascular Plasticity And Long-term Functional Recovery.

Background: Stroke associated with pre-existing diabetes worsens ischemic injury and impairs recovery. We have previously shown that type-2-diabetic rats subjected to cerebral ischemic reperfusion injury develop hemorrhagic transformation (HT) and greater neurological deficits. These diabetic rats also exhibit enhanced dysfunctional cerebral neovascularization that increases the risk of bleeding post-stroke. However, our knowledge of vascular and functional plasticity during the recovery phase of diabetic stroke is limited. This study tested the hypothesis that post-stroke neovascularization is impaired in diabetes and this is associated with poor sensorimotor and cognitive outcomes. Methods: Reparative neovascularization was assessed in the lesional and non-lesional areas in diabetic rats after 14 days of ischemic reperfusion injury. 3-dimensional reconstruction of the FITC stained vasculature were obtained by confocal microscopy and stereological parameters including vascular volume and surface area were measured. Astrogliosis was also determined by GFAP staining. The relative rates of sensorimotor recovery, cognitive decline and spontaneous activity were assessed. Results: Diabetes impairs reparative neovascularization in the lesional areas compared to control rats. Astroglial swelling and reactivity was pronounced in diabetic stroke compared to control stroke. Rate of sensorimotor recovery was significantly slower in diabetic stroke compared to the controls. Diabetes also exacerbated anxiety-like symptoms and cognitive decline post-stroke relative to control. Conclusion: Diabetes impairs post-stroke reparative neovascularization and impedes functional recovery. The impact of glycemic control on poor recovery in this critical period needs to be tested. N=6-8 * p≤ 0.05, ** p≤ 0.005