title: Activation of GPER-1 estradiol receptor downregulates production of testosterone in isolated rat Leydig cells and adult human testis.
abstract: OBJECTIVE
  Estradiol (E2) modulates testicular functions including steroidogenesis, but the mechanisms of E2 signaling in human testis are poorly understood. GPER-1 (GPR30), a G protein-coupled membrane receptor, mediates rapid genomic and non-genomic response to estrogens. The aim of this study was to evaluate GPER-1 expression in the testis, and its role in estradiol dependent regulation of steroidogenesis in isolated rat Leydig cells and human testis.
  
  
  METHODS
  Isolated Leydig cells (LC) from adult rats and human testicular tissue were used in this study. Expression and localization studies of GPER-1 were performed with qRT-PCR, immunofluorescence, immunohistochemistry and Western Blot. Luteinizing Hormone (LH) -stimulated, isolated LC were incubated with estradiol, G-1 (GPER-1-selective agonist), and estrogen receptor antagonist ICI 182,780. Testosterone production was measured with radioimmunoassay. LC viability after incubation with G-1 was measured using 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium, inner salt (MTS) assay.
  
  
  RESULTS
  GPER-1 mRNA is abundantly expressed in rat LC and human testis. Co-localization experiments showed high expression levels of GPER-1 protein in LC. E2-dependent activation of GPER-1 lowers testosterone production in isolated rats LCs and in human testis, with statistically and clinically significant drops in testosterone production by 20-30% as compared to estradiol-naïve LC. The exposure to G-1 does not affect viability of isolated LCs.
  
  
  CONCLUSIONS
  Our results indicate that activation of GPER-1 lowers testosterone levels in the rat and human testis. The expression of GPER-1 in human testis, which lack ERα, makes it an exciting target for developing new agents affecting testosterone production in men.
authors.affiliation: Department of Urology and Reproductive Medicine, Weill Cornell Medical College, New York, New York, United States of America; Population Council, Center for Biomedical Research, New York, New York, United States of America; Department of Urology, Centre Hospitalier Universitaire Vaudois, Lausanne, Switzerland.
authors.forename: Laurent
authors.initials: L
authors.lastname: Vaucher
authors.affiliation: Department of Urology and Reproductive Medicine, Weill Cornell Medical College, New York, New York, United States of America.
authors.forename: Michael G
authors.initials: MG
authors.lastname: Funaro
authors.affiliation: Department of Urology and Reproductive Medicine, Weill Cornell Medical College, New York, New York, United States of America.
authors.forename: Akanksha
authors.initials: A
authors.lastname: Mehta
authors.affiliation: Department of Urology and Reproductive Medicine, Weill Cornell Medical College, New York, New York, United States of America.
authors.forename: Anna
authors.initials: A
authors.lastname: Mielnik
authors.affiliation: Department of Urology and Reproductive Medicine, Weill Cornell Medical College, New York, New York, United States of America; Population Council, Center for Biomedical Research, New York, New York, United States of America.
authors.forename: Alexander
authors.initials: A
authors.lastname: Bolyakov
authors.affiliation: Department of Cell Biology and Physiology, University of New Mexico, Albuquerque, New Mexico, United States of America.
authors.forename: Eric R
authors.initials: ER
authors.lastname: Prossnitz
authors.affiliation: Department of Urology and Reproductive Medicine, Weill Cornell Medical College, New York, New York, United States of America; Population Council, Center for Biomedical Research, New York, New York, United States of America.
authors.forename: Peter N
authors.initials: PN
authors.lastname: Schlegel
authors.affiliation: Department of Urology and Reproductive Medicine, Weill Cornell Medical College, New York, New York, United States of America; Population Council, Center for Biomedical Research, New York, New York, United States of America.
authors.forename: Darius A
authors.initials: DA
authors.lastname: Paduch
mesh_terms: D000818:Animals; D002470:Cell Survival / Q000187:drug effects; D004958:Estradiol / Q000031:analogs & derivatives / Q000494:pharmacology; D000077267:Fulvestrant; D015870:Gene Expression; D006801:Humans; D007985:Leydig Cells / Q000187:drug effects / Q000378:metabolism*; D008297:Male; D021381:Protein Transport; D051381:Rats; D011960:Receptors, Estrogen / Q000235:genetics / Q000378:metabolism*; D043562:Receptors, G-Protein-Coupled / Q000235:genetics / Q000378:metabolism*; D013737:Testis / Q000378:metabolism*; D013739:Testosterone / Q000096:biosynthesis*
chemical_list: D011960:Receptors, Estrogen; D043562:Receptors, G-Protein-Coupled; D000077267:Fulvestrant; D013739:Testosterone; D004958:Estradiol
references.citation: J Androl. 2002 Nov-Dec;23(6):870-81
references.pmid: 12399534
references.citation: Endocrinology. 2008 Oct;149(10):5043-51
references.pmid: 18566133
references.citation: Endocrinology. 2003 Jan;144(1):84-93
references.pmid: 12488333
references.citation: J Androl. 2001 Jul-Aug;22(4):665-71
references.pmid: 11451364
references.citation: Endocrinology. 2005 May;146(5):2454-61
references.pmid: 15661855
references.citation: Trends Endocrinol Metab. 2005 Jul;16(5):222-7
references.pmid: 15936211
references.citation: Steroids. 2006 Apr;71(4):310-6
references.pmid: 16289637
references.citation: J Endocrinol. 2000 May;165(2):359-70
references.pmid: 10810300
references.citation: J Clin Endocrinol Metab. 1980 May;50(5):938-48
references.pmid: 7372780
references.citation: Mol Endocrinol. 2008 Mar;22(3):636-48
references.pmid: 18063692
references.citation: Steroids. 1999 Sep;64(9):610-7
references.pmid: 10503717
references.citation: Endocrinology. 2008 Oct;149(10):4846-56
references.pmid: 18566127
references.citation: Endocrinology. 2004 Oct;145(10):4441-6
references.pmid: 15231695
references.citation: J Clin Endocrinol Metab. 2002 Jun;87(6):2706-15
references.pmid: 12050238
references.citation: Nature. 1997 Dec 4;390(6659):509-12
references.pmid: 9393999
references.citation: Mol Endocrinol. 2000 Oct;14(10):1649-60
references.pmid: 11043579
references.citation: Reprod Biol Endocrinol. 2005 Sep 27;3:51
references.pmid: 16188042
references.citation: ACS Chem Biol. 2007 Aug 17;2(8):536-44
references.pmid: 17655271
references.citation: Endocrinology. 1978 Oct;103(4):1096-102
references.pmid: 217666
references.citation: Cancer Res. 2007 Feb 15;67(4):1859-66
references.pmid: 17308128
references.citation: Crit Rev Oncol Hematol. 2013 Sep;87(3):224-38
references.pmid: 23484454
references.citation: Reproduction. 2013 Mar 07;145(3):255-63
references.pmid: 23319664
references.citation: Eur J Endocrinol. 1997 Jun;136(6):633-9
references.pmid: 9225728
references.citation: Reprod Biol Endocrinol. 2003 Jul 09;1:52
references.pmid: 12904263
references.citation: Annu Rev Physiol. 2008;70:165-90
references.pmid: 18271749
references.citation: Andrologia. 2013 Jun;45(3):187-94
references.pmid: 22734680
references.citation: PLoS One. 2013 Aug 15;8(8):e71722
references.pmid: 23967237
references.citation: N Engl J Med. 2013 Dec 19;369(25):2456
references.pmid: 24350957
references.citation: Nat Chem Biol. 2006 Apr;2(4):207-12
references.pmid: 16520733
references.citation: Invest Urol. 1981 Nov;19(3):142-7
references.pmid: 6170603
references.citation: Mol Endocrinol. 2002 Jan;16(1):70-84
references.pmid: 11773440
references.citation: Science. 2005 Mar 11;307(5715):1625-30
references.pmid: 15705806