IMMEDIATE-EARLY GENE-EXPRESSION IN RESPONSE TO CEREBRAL-ISCHEMIA - FRIEND OR FOE

Background Cerebral ischemia is a potent modulator of gene expression. Immediate early genes undergo rapid induction after both, global and focal cerebral ischemia. Many immediate early genes code for transcrip tion factors. Additional genes, including those encoding for neurotrop hic factors and neurotransmitter systems, are induced in a delayed fas hion after cerebral ischemia. The functional significance of early and late gene regulation after cerebral ischemia requires futher investig ation. These changes may be beneficial (friend) or detrimental (foe). Many of the genes are likely neuroprotective and important for recover y, but others may be involved in ischemic cell death mediated by apopt osis. Summary of Review We review evidence that supports the hypothesi s that cell death after cerebral ischemia occurs through the dual path ways of ischemic necrosis and apoptosis. Conclusions Gene regulation, including immediate early genes, is required for programmed neuronal d eath after trophic factor deprivation and is predicted to be involved in apoptosis triggered by cerebral ischemia. Novel therapies following cerebral ischemia may be directed at genes mediating either recovery or apoptosis.