[Oestrogens and neurogenesis: new functions for an old hormone. Lessons from the zebrafish].
In contrast to other vertebrates, in which the adult brain shows limited adult neurogenesis, teleost fish exhibit an unparalleled capacity to generate new neurons as adults, suggesting that their brains present a highly permissive environment for the maintenance and proliferation of adult progenitors. Here, we examine the hypothesis that one of the factors permitting establishment of this favourable environment is estradiol. Indeed, recent data showed that radial glial cells strongly expressed one of two aromatase duplicated genes. Aromatase is the estrogen-synthesizing enzyme and this observation is of great interest, given that radial glial cells are progenitor cells capable of generating new neurons. Given the well documented roles of estrogens on cell fate, and notably on cell proliferation, these data suggest that estradiol could be involved in maintaining and/or activating these progenitors. Examination of recent data in birds and mammals suggests that the situation in fish could well be an exaggeration of a more general mechanism implicating estrogens in neurogenesis. Indeed, there is accumulating evidence that estrogens are involved in embryonic, adult or reparative neurogenesis in other vertebrates, notably in mammals.
Neurogenèse, Aromatase et OEstrogènes, Université de Rennes 1, UMR CNRS 6026, Campus de Beaulieu, 35042 Rennes Cedex, France. olivier.kah@univ-rennes1.fr
Olivier
O
Kah
Elisabeth
E
Pellegrini
Karen
K
Mouriec
Nicolas
N
Diotel
Isabelle
I
Anglade
Colette
C
Vaillant
Marie-Lise
ML
Thieulant
Sok-Keng
SK
Tong
François
F
Brion
Bon-Chu
BC
Chung
Farzad
F
Pakdel
D000818:Animals; D001141:Aromatase / Q000502:physiology; D001717:Birds / Q000502:physiology; D001921:Brain / Q000166:cytology / Q000201:enzymology; D002455:Cell Division; D004967:Estrogens / Q000096:biosynthesis / Q000502:physiology*; D008322:Mammals / Q000502:physiology; D009419:Nerve Tissue Proteins / Q000502:physiology; D055495:Neurogenesis / Q000502:physiology*; D009457:Neuroglia / Q000201:enzymology; D009474:Neurons / Q000166:cytology / Q000201:enzymology; D012038:Regeneration; D013045:Species Specificity; D013234:Stem Cells / Q000166:cytology / Q000201:enzymology; D015027:Zebrafish / Q000235:genetics / Q000502:physiology*; D029961:Zebrafish Proteins / Q000502:physiology
D004967:Estrogens; D009419:Nerve Tissue Proteins; D029961:Zebrafish Proteins; D001141:Aromatase; C440729:Cyp19a1a protein, zebrafish; C440728:Cyp19a1b protein, zebrafish