Estrogens, apoptosis and cells of neural origin.

In mammals, estrogens have a multiplicity of effects in all known neural cells. We review here some of the mechanisms enabling estrogens to differentiate their influence on neural targets. In view of the potential interest in the use of estrogens in the therapy of several pathologies of the nervous system, we have proposed the use of a reductionist approach for the systematic understanding of estrogen activities in each specific type of target cell. We have therefore generated a model system in which to study the activation of one of the known estrogen receptors: estrogen receptor alpha. This system allowed us to identify a number of novel genes, the expression of which may be influenced following the activation of this receptor subtype by estradiol. We here report on preliminary data obtained by the study of one of these target genes, nip2, which encodes a proapoptotic protein product. We hypothesize that Nip2 might be an important molecular determinant for estrogen anti-apoptotic activity in cells of neural origin.