Stroke is the leading cause of long term-morbidity in aged people, but effective therapies still need to be developed. Stroke treatment design should cover all stages of the ischemic cascade, starting with the primary injury until the tissue regeneration and repair stage. Cerebral ischemia occur when the blood supply is decreased or interupted in the brain. Primary insult of the brain tissue is caused by deprivation of oxygen and glucose that are essential for neuronal cells to work and survive, and then continue with excitotoxicity phenomenon caused by glutamate release and calcium-dependent mitochondrial disfunction followed by DNA degradation and neuronal cell death.
Free radicals are other molecules that contribute to tissue destruction. Irreversible cell death occurs rapidly in the “core” of lesioned aria and progress faster in the adjacent area in the absence of a rapid intervention. This stage decides the fate of viable neurovascular unit cells to death or neurorepair and also, the fate of grafted stem cells. However, the only approved FDA drug, aimed to restore the blood flow, is tissue plasminogen activator (rt-PA). rt-PA wich has a limited time window (first 6 hours) and an increased risk of hemorrhagic complication.