Estrogen can protect neurons: modes of action.

The female sex hormone estrogen is a steroid that activates estrogen receptors which may act as nuclear transcription factors. In addition to its well-known functions in reproductive tissue, estrogen and its receptors may also act in various regions throughout the body including the brain. Recently, the neuroprotective functions of estrogen have been investigated in greater detail. Besides acting as a powerful neuroprotective antioxidant molecule estrogen may activate the transcription of neuroprotective genes directly and may cross-talk with various intracellular signaling processes. The various modes of action of estrogen via receptor activation and in a non-receptor fashion are currently under intensive investigation.