Are Estrogens Protective or Risk Factors in the Brain? Insights Derived From Animal Models

  • Phyllis M. Wise
  • Dena B. Dubal
Part of the Research and Perspectives in Endocrine Interactions book series (RPEI)

Summary

We now understand that estrogens are pleiotropic gonadal steroids that influence plasticity and cell survival of the adult brain. Over the past century, the life span of women has increased from approximately 50 to 80 years of age, but the timing of the menopause remains constant and occurs at approximately 50 years of age. This means that women may now live over one-third of their lives in a hypo-estrogenic, postmenopausal state. The impact of prolonged hypoestrogenicity on the the well-being of women and, in particular, on their brains is a critical health concern since it appears that these older women may suffer an increased risk of cognitive dysfunction and neurodegeneration due to a variety of diseases. Accumulating evidence from both clinical and basic science studies indicates that estrogens may exert critical protective actions against neurodegenerative conditions such as Alzheimer’s disease (AD) and stroke. However, new evidence purports to suggest that, under some circumstances, hormone replacement may not decrease the risk of neurodegenerative diseases and may, in fact, increase risk of cerebrovascular stroke. Here, we review the discoveries that comprise our current understanding of estrogen action against neurodegeneration. These findings carry far-reaching implications for improving the health and quality of life of aging women.

Keywords

Ischemia Estrogen Androgen Estradiol Activin 

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Copyright information

© Springer-Verlag Berlin Heidelberg 2004

Authors and Affiliations

  • Phyllis M. Wise
  • Dena B. Dubal

There are no affiliations available

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