Neuroprotection by the steroids pregnenolone and dehydroepiandrosterone is mediated by the enzyme aromatase.

@article{Veiga2003NeuroprotectionBT,
  title={Neuroprotection by the steroids pregnenolone and dehydroepiandrosterone is mediated by the enzyme aromatase.},
  author={Sergio J. Veiga and Luis Miguel Garcia-Segura and {\'I}{\~n}igo Azcoitia},
  journal={Journal of neurobiology},
  year={2003},
  volume={56 4},
  pages={
          398-406
        }
}
Pregnenolone and dehydroepiandrosterone (DHEA) are sex hormone precursors and neuroprotective steroids. Effects of pregnenolone and DHEA may be in part mediated by their conversion to testosterone and by the consecutive conversion of testosterone to estradiol by the enzyme aromatase. This enzyme is induced in reactive astrocytes after different forms of neurodegenerative lesions and the resultant local production of estradiol in the brain has been shown to be neuroprotective. The participation… 
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