| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Testis |
a Institute for Hormone and Fertility Research, University of Hamburg, D-22529 Hamburg, Germany
b Department of Cell Biology and Biochemistry, Texas Tech University Health Sciences Center, Lubbock, Texas 79430
The steroidogenic acute regulatory protein (StAR), by virtue of its ability to facilitate the intramitochondrial transport of cholesterol, plays an important role in regulating steroid hormone biosynthesis in steroidogenic cells. In agreement with published data, both StAR expression and progesterone production in MA-10 mouse Leydig tumor cells could be stimulated with hCG and 8Br-cAMP. Addition of aminoglutethimide, an inhibitor of cholesterol side chain cleavage (P450scc) enzyme, not only resulted in a drastic inhibition of progesterone production but also in an attenuation of StAR expression in response to either hCG or 8-Br-cAMP. Therefore, we addressed the question of whether progesterone, the end product of the steroidogenic cascade in these cells, could be in a position to regulate the StAR gene expression. In MA-10 cells, we report here that progesterone in microgram amounts can induce StAR gene expression in a time- and dose-dependent manner. StAR expression in response to a maximally effective concentration of progesterone of 10 µg/ml was highest at 6 h and started decreasing thereafter. The effect of progesterone on StAR protein and StAR mRNA induction was mimicked by its synthetic analog, progestin R5020, but not by other steroids, including dexamethasone, estradiol, testosterone, and dihydrotestosterone. Dexamethasone, in contrast, was able to inhibit StAR expression in MA-10 cells. Surprisingly, RU486, a potent antagonist of progesterone and glucocorticoid action, had a stimulatory effect on StAR mRNA levels. Reverse transcription-polymerase chain reaction analysis demonstrated the absence of the classical form of progesterone receptor in MA-10 cells. Thus, for the first time, a direct stimulatory effect of a steroid on StAR gene expression has been demonstrated. Furthermore, these results provide a new insight, indicating that progesterone mediates the activation of StAR expression exerted presumably through a novel, nonclassical progesterone receptor in mouse Leydig cells.
2 Correspondence: Amal K. Mukhopadhyay, Institute for Hormone and Fertility Research, Grandweg 64, D-22529 Hamburg, Germany. FAX: 49 40 56 19 08 64; e-mail: amal{at}ihf.de
This article has been cited by other articles:
|
|
 |
|
  L. J Martin and J. J Tremblay Glucocorticoids antagonize cAMP-induced Star transcription in Leydig cells through the orphan nuclear receptor NR4A1 J. Mol. Endocrinol., September 1, 2008; 41(3): 165 - 175. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 D. Seto-Young, D. Avtanski, M. Strizhevsky, G. Parikh, P. Patel, J. Kaplun, K. Holcomb, Z. Rosenwaks, and L. Poretsky Interactions among Peroxisome Proliferator Activated Receptor-{gamma}, Insulin Signaling Pathways, and Steroidogenic Acute Regulatory Protein in Human Ovarian Cells J. Clin. Endocrinol. Metab., June 1, 2007; 92(6): 2232 - 2239. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 Q. Li, F. Jimenez-Krassel, A. Bettegowda, J. J Ireland, and G. W Smith Evidence that the preovulatory rise in intrafollicular progesterone may not be required for ovulation in cattle J. Endocrinol., March 1, 2007; 192(3): 473 - 483. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 Z. Zhang and J. Hu Development and Validation of Endogenous Reference Genes for Expression Profiling of Medaka (Oryzias latipes) Exposed to Endocrine Disrupting Chemicals by Quantitative Real-Time RT-PCR Toxicol. Sci., February 1, 2007; 95(2): 356 - 368. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
P. R Manna, S. P Chandrala, Y. Jo, and D. M Stocco cAMP-independent signaling regulates steroidogenesis in mouse Leydig cells in the absence of StAR phosphorylation. J. Mol. Endocrinol., August 1, 2006; 37(1): 81 - 95. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 J. J. Peluso, A. Pappalardo, R. Losel, and M. Wehling Progesterone Membrane Receptor Component 1 Expression in the Immature Rat Ovary and Its Role in Mediating Progesterone's Antiapoptotic Action Endocrinology, June 1, 2006; 147(6): 3133 - 3140. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
D. Muller, L. Cortes-Dericks, L. T. Budnik, B. Brunswig-Spickenheier, M. Pancratius, R. C. Speth, A. K. Mukhopadhyay, and R. Middendorff Homologous and Lysophosphatidic Acid-Induced Desensitization of the Atrial Natriuretic Peptide Receptor, Guanylyl Cyclase-A, in MA-10 Leydig Cells Endocrinology, June 1, 2006; 147(6): 2974 - 2985. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 H. Wang, L. Zhou, A. Gupta, R. R. Vethanayagam, Y. Zhang, J. D. Unadkat, and Q. Mao Regulation of BCRP/ABCG2 expression by progesterone and 17beta-estradiol in human placental BeWo cells Am J Physiol Endocrinol Metab, May 1, 2006; 290(5): E798 - E807. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
R.-S. Ge, Q. Dong, E.-m. Niu, C. M. Sottas, D. O. Hardy, J. F. Catterall, S. A. Latif, D. J. Morris, and M. P. Hardy 11{beta}-Hydroxysteroid Dehydrogenase 2 in Rat Leydig Cells: Its Role in Blunting Glucocorticoid Action at Physiological Levels of Substrate Endocrinology, June 1, 2005; 146(6): 2657 - 2664. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
C. Shah, D. Modi, G. Sachdeva, S. Gadkar, and C. Puri Coexistence of Intracellular and Membrane-Bound Progesterone Receptors in Human Testis J. Clin. Endocrinol. Metab., January 1, 2005; 90(1): 474 - 483. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
C. P. Houk, E. J. Pearson, N. Martinelle, P. K. Donahoe, and J. Teixeira Feedback Inhibition of Steroidogenic Acute Regulatory Protein Expression in Vitro and in Vivo by Androgens Endocrinology, March 1, 2004; 145(3): 1269 - 1275. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 H. Schwarzenbach, G. Chakrabarti, H. J. Paust, and A. K. Mukhopadhyay Gonadotropin-Mediated Regulation of the Murine VEGF Expression in MA-10 Leydig Cells J Androl, January 1, 2004; 25(1): 128 - 139. [Abstract] [Full Text] [PDF]
|
|
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
