Sex steroid hormone metabolism takes place in human ocular cells

Department of Ophthalmology and Visual Science, Yale University School of Medicine, 330 Cedar Street, New Haven, CT 06510, USA.
The Journal of Steroid Biochemistry and Molecular Biology (Impact Factor: 3.63). 08/2003; 86(2):207-16. DOI: 10.1016/j.jsbmb.2003.08.001
Source: PubMed


Steroids are potentially important mediators in the pathophysiology of ocular diseases. In this study, we report on the gene expression in the human eye of a group of enzymes, the 17beta-hydroxysteroid dehydrogenases (17HSDs), involved in the biosynthesis and inactivation of sex steroid hormones. In the eye, the ciliary epithelium, a neuroendocrine secretory epithelium, co-expresses the highest levels of 17HSD2 and 5 mRNAs, and in lesser level 17HSD7 mRNA. The regulation of gene expression of these enzymes was investigated in vitro in cell lines, ODM-C4 and chronic open glaucoma (GCE), used as cell models of the human ciliary epithelium. The estrogen, 17beta-estradiol (10(-7) M) and androgen agonist, R1881 (10(-8) M) elicited in ODM-C4 and GCE cells over a 24 h time course a robust up-regulation of 17HSD7 mRNA expression. 17HSD2 was up-regulated by estradiol in ODM-C4 cells, but not in GCE cells. Under steady-state conditions, ODM-C4 cells exhibited a predominant 17HSD2 oxidative enzymatic activity. In contrast, 17HSD2 activity was low or absent in GCE cells. Our collective data suggest that cultured human ciliary epithelial cells are able to metabolize estrogen, androgen and progesterone, and that 17HSD2 and 7 in these cells are sex steroid hormone-responsive genes and 17HSD7 is responsible to keep on intra/paracrine estrogenic milieu.

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Available from: Julio Escribano
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    • "ERs have also been detected in the neuroendocrine secretory and metabolic ciliary epithelium. 17β-hydroxysteroid dehydrogenases (17HSDs), involved in the biosynthesis and inactivation for sex steroids, were shown to be under direct paracrine influence of 17β-estradiol, evidence of estrogen modulating its own fate within the eye [28]. The presence of estrogen receptors and metabolic machinery within the eye suggest that estrogens play more than a passive role in the retina. "
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