Human fetal testis: source of estrogen and target of estrogen action.
BACKGROUND
Estrogens are involved in masculine fertility and spermatogenesis. However, little is known about estrogen involvement in human testicular organogenesis. Therefore the aim of this study was to investigate the cellular sources and targets of estrogens and their variations in the human testis during fetal development. Expression profiles of aromatase (CYP19) and estrogen receptors (ER) alpha and beta were analysed in human fetal testes at various gestational stages by immunohistochemistry and quantitative RT-PCR.


METHODS
Fifty-four archival paraffin-embedded and four frozen fetal testes were studied by immunohistochemistry and real-time PCR. Tissue quality was confirmed by histology and expression of specific functional markers: androgenic enzymes for Leydig cells, anti-Müllerian hormone for Sertoli cells and Steel factor receptor for germ cells.


RESULTS
We demonstrate that the human fetal testes express aromatase and ERbeta simultaneously in Sertoli, Leydig and germ cells but are devoid of ERalpha. Quantification of positive cells indicates a window of protein expression, especially between 13 and 22-24 weeks. Quantitative RT-PCR confirmed that the human fetal testis expresses CYP19 and ERbeta but not ERalpha mRNA.


CONCLUSIONS
Our findings suggest that locally produced estrogens influence human testicular development through autocrine and paracrine mechanisms, most notably during the period of maximal testicular susceptibility to endocrine disruptors.
Boukari
Kahina
K
University Paris-Sud, UMR-S 693 Le kremlin Bicêtre Cedex F-94276, France.
Ciampi
Maria Luisa
ML
Guiochon-Mantel
Anne
A
Young
Jacques
J
Lombès
Marc
M
Meduri
Geri
G
D001141:Aromatase / Q000378:metabolism; D004967:Estrogens / Q000378:metabolism*; D006801:Humans; D007150:Immunohistochemistry; D007985:Leydig Cells / Q000378:metabolism; D008297:Male; D008954:Models, Biological; D012333:RNA, Messenger / Q000378:metabolism; D011960:Receptors, Estrogen / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012708:Sertoli Cells / Q000378:metabolism; D013090:Spermatocytes / Q000378:metabolism; D013091:Spermatogenesis; D013737:Testis / Q000196:embryology*
D004967:Estrogens; D012333:RNA, Messenger; D011960:Receptors, Estrogen; D001141:Aromatase