![]() |
|
|
JC Corton, C Bocos, ES Moreno, A Merritt, DS Marsman, PJ Sausen, RC Cattley and JA Gustafsson
Chemical Industry Institute of Toxicology, Research Triangle Park, North Carolina 27709, USA. corton@ciit.org
To better understand the molecular mechanisms of the pleiotropic responses induced by exposure to peroxisome proliferator chemicals (PPCs), we conducted a systematic search for genes whose mRNA levels are modulated by the PPC WY-14,643 (WY) in rat liver. The sequence of one up-regulated cDNA (2480 bp) was predicted to encode a protein of 735 aa with 82% identity to the porcine 17 beta-hydroxysteroid dehydrogenase type IV (HSD IV). Like the porcine enzyme, the rat HSD IV contains' a region homologous to yeast hydratase-dehydrogenase- epimerases and to sterol carrier proteins, indicating that the rat HSD IV has broad substrate specificity and contributes to cholesterol metabolism. The rat HSD IV was regulated by diverse PPCs via two distinct mechanisms. Induction of HSD IV and acyl-CoA oxidase (ACO) proteins in rat liver at different treatment times and concentrations of gemfibrozil and di-n-butyl phthalate were almost identical, indicating that HSD IV mRNA induction involves the peroxisome proliferator-activated receptor alpha, a regulator of ACO. In contrast, HSD IV protein levels were only weakly induced by WY, a strong inducer of ACO protein, even though the levels of HSD IV and ACO mRNA were strongly stimulated by WY and gemfibrozil. Thus, HSD IV protein levels were uniquely regulated pretranslationally by WY via a novel mechanism. Increased conversion of estradiol to the less-active estrone by HSD IV induction may explain how phthalate exposure leads to decreases in serum estradiol levels and suppression of ovulation.
This article has been cited by other articles:
![]() |
Y. Nagayoshi, T. Ohba, H. Yamamoto, Y. Miyahara, H. Tashiro, H. Katabuchi, and H. Okamura Characterization of 17{beta}-hydroxysteroid dehydrogenase type 4 in human ovarian surface epithelial cells Mol. Hum. Reprod., September 1, 2005; 11(9): 615 - 621. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. C. Corton and P. J. Lapinskas Peroxisome Proliferator-Activated Receptors: Mediators of Phthalate Ester-Induced Effects in the Male Reproductive Tract? Toxicol. Sci., January 1, 2005; 83(1): 4 - 17. [Abstract] [Full Text] [PDF] |
||||
![]() |
K. A. Brown, D. Boerboom, N. Bouchard, M. Dore, J. G. Lussier, and J. Sirois Human Chorionic Gonadotropin-Dependent Regulation of 17{beta}-Hydroxysteroid Dehydrogenase Type 4 in Preovulatory Follicles and Its Potential Role in Follicular Luteinization Endocrinology, April 1, 2004; 145(4): 1906 - 1915. [Abstract] [Full Text] [PDF] |
||||
![]() |
K. Toda, T. Okada, C. Miyaura, and T. Saibara Fenofibrate, a ligand for PPAR{alpha}, inhibits aromatase cytochrome P450 expression in the ovary of mouse J. Lipid Res., February 1, 2003; 44(2): 265 - 270. [Abstract] [Full Text] [PDF] |
||||
![]() |
R.-S. Ge and M. P. Hardy Variation in the End Products of Androgen Biosynthesis and Metabolism during Postnatal Differentiation of Rat Leydig Cells Endocrinology, September 1, 1998; 139(9): 3787 - 3795. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. C. Corton, L.-Q. Fan, S. Brown, S. P. Anderson, C. Bocos, R. C. Cattley, A. Mode, and J.-A. Gustafsson Down-Regulation of Cytochrome P450 2C Family Members and Positive Acute-Phase Response Gene Expression by Peroxisome Proliferator Chemicals Mol. Pharmacol., September 1, 1998; 54(3): 463 - 473. [Abstract] [Full Text] |
||||
![]() |
P. Nokelainen, H. Peltoketo, R. Vihko, and P. Vihko Expression Cloning of a Novel Estrogenic Mouse 17{beta}-Hydroxysteroid Dehydrogenase/ 17-Ketosteroid Reductase (m17HSD7), Previously Described as a Prolactin Receptor-Associated Protein (PRAP) in Rat Mol. Endocrinol., July 1, 1998; 12(7): 1048 - 1059. [Abstract] [Full Text] |
||||