title: A transcriptome-wide screen for mRNAs enriched in fetal Leydig cells: CRHR1 agonism stimulates rat and mouse fetal testis steroidogenesis.
abstract: Fetal testis steroidogenesis plays an important role in the reproductive development of the male fetus. While regulators of certain aspects of steroidogenesis are known, the initial driver of steroidogenesis in the human and rodent fetal testis is unclear. Through comparative analysis of rodent fetal testis microarray datasets, 54 candidate fetal Leydig cell-specific genes were identified. Fetal mouse testis interstitial expression of a subset of these genes with unknown expression (Crhr1, Gramd1b, Itih5, Vgll3, and Vsnl1) was verified by whole-mount in situ hybridization. Among the candidate fetal Leydig cell-specific factors, three receptors (CRHR1, PRLR, and PROKR2) were tested for a steroidogenic function using ex vivo fetal testes treated with receptor agonists (CRH, PRL, and PROK2). While PRL and PROK2 had no effect, CRH, at low (approximately 1 to 10) nM concentration, increased expression of the steroidogenic genes Cyp11a1, Cyp17a1, Scarb1, and Star in GD15 mouse and GD17 rat testes, and in conjunction, testosterone production was increased. Exposure of GD15 fetal mouse testis to a specific CRHR1 antagonist blunted the CRH-induced steroidogenic gene expression and testosterone responses. Similar to ex vivo rodent fetal testes, ≥ 10 nM CRH exposure of MA-10 Leydig cells increased steroidogenic pathway mRNA and progesterone levels, showing CRH can enhance steroidogenesis by directly targeting Leydig cells. Crh mRNA expression was observed in rodent fetal hypothalamus, and CRH peptide was detected in rodent amniotic fluid. Together, these data provide a resource for discovering factors controlling fetal Leydig cell biology and suggest that CRHR1 activation by CRH stimulates rat and mouse fetal Leydig cell steroidogenesis in vivo.
authors.affiliation: Nemours Biomedical Research, Alfred I. DuPont Hospital for Children, Wilmington, Delaware, United States of America.
authors.forename: Erin N
authors.initials: EN
authors.lastname: McDowell
authors.forename: Anne E
authors.initials: AE
authors.lastname: Kisielewski
authors.forename: Jack W
authors.initials: JW
authors.lastname: Pike
authors.forename: Heather L
authors.initials: HL
authors.lastname: Franco
authors.forename: Humphrey H-C
authors.initials: HH
authors.lastname: Yao
authors.forename: Kamin J
authors.initials: KJ
authors.lastname: Johnson
mesh_terms: D000653:Amniotic Fluid / Q000378:metabolism; D000818:Animals; D002097:C-Reactive Protein / Q000378:metabolism; D005768:Gastrointestinal Hormones / Q000378:metabolism; D018507:Gene Expression Regulation, Developmental; D023281:Genomics; D007150:Immunohistochemistry / Q000379:methods; D007985:Leydig Cells / Q000378:metabolism*; D008297:Male; D051379:Mice; D009479:Neuropeptides / Q000378:metabolism; D020411:Oligonucleotide Array Sequence Analysis; D011388:Prolactin / Q000096:biosynthesis; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D018019:Receptors, Corticotropin-Releasing Hormone / Q000819:agonists* / Q000502:physiology*; D013256:Steroids / Q000378:metabolism; D013737:Testis / Q000196:embryology*; D013739:Testosterone / Q000378:metabolism; D013997:Time Factors; D054832:Urocortins / Q000378:metabolism; D000099052:CRF Receptor, Type 1
chemical_list: D005768:Gastrointestinal Hormones; D009479:Neuropeptides; C486586:Prok2 protein, mouse; D012333:RNA, Messenger; D018019:Receptors, Corticotropin-Releasing Hormone; D013256:Steroids; C549377:Ucn1 protein, mouse; D054832:Urocortins; D013739:Testosterone; D000099052:CRF Receptor, Type 1; D011388:Prolactin; D002097:C-Reactive Protein