Ischemic brain injuries: the need for new neuroprotective strategies

Ischemic injury occurs when the blood supply to the tissue is cut off. The length of time a tissue can survive under ischemic insults varies, but eventually all ischemic tissues become apoptotic and/or necrotic (Lipton, 1999). The major pathophysiological effects are caused by the reduction in the oxygen and glucose levels, followed by the renewal of blood supply, responsible for the oxidative damage to the tissue (Mehta et al., 2007). brain tissue has a complex differential sensitivity towards ischemic insult. Astrocytes can survive from energy deprivation for a prolonged period and are most sensitive to the burst of reactive oxygen species, on the other hand neurons are highly sensitive to oxygen and glucose deprivation (Hertz, 2008). Therefore, global brain ischemia triggers a complex series of biochemical and molecular mechanisms that impairs the neuNeuroprotection by human umbilical cord bloodderived progenitors in ischemic brain injuries