Role of colony stimulating factor-1 in brain damage caused by ischemia

A marked effect of colony stimulating factor-1(CSF-1) on microglial response and neuron survival in cerebral cortex ischemic damage was observed. In osteopetrotic op/op mice, which lack systemically functional CSF-1 microglia do not respond to ischemic damage to the cerebral cortex, and the infarcts are considerably larger than in CSF-1 producing mice with similar vascular impairment. Delivery of extraneous CSF-1 to op/op mice alleviates the functional deficiency of the microglia and potentiates neuron survival in ischemic lesion. Delivery of extraneous recombinant CSF-1 to normal CSF-1 producing mice does not increase either the number or degree of activation of microglia, but does further potentiate neuronal survival. We found that neurons in the cerebral cortex have active CSF-1 receptors, and we therefore propose that neuronal rescue in cerebral cortex ischemic damage is linked to activation of the CSF-1 receptor on neurons.