Estrogen as a neuroprotective agent in the treatment of spinal cord injury.

The following review is a brief discussion about spinal cord injury and the possibility of using estrogen as a neuroprotective agent. There are several pathways by which secondary cell death can occur following spinal cord injury, including infiltration of inflammatory cells, generation of reactive oxygen species, decreases in spinal cord blood flow, and increases in intracellular Ca(2+) levels. This secondary damage leads to apoptotic cell death, and the neuroprotective effects of pharmacologic agents have been investigated using experimentally induced spinal cord injury in animals. Currently, only high-dose methylprednisolone is advocated for the treatment of patients following spinal cord injury. Estrogen has been shown to be neuroprotective in both in vitro and in vivo studies. There are several possible mechanisms of action by which estrogen may attenuate damage following spinal cord injury and improve functional outcome. Estrogen has been shown to have anti-inflammatory properties. Estrogen levels are correlated with an increase in post-traumatic blood flow to injured tissue. Estrogen may also upregulate protein levels of anti-apoptotic Bcl-2 and may attenuate the post-traumatic influx of Ca(2+).