title: Human GnRH-secreting cultured neurons express activin betaA subunit mRNA and secrete dimeric activin A.
abstract: OBJECTIVE
  To evaluate the expression of activin betaA-subunit mRNA and the secretion of activin A in/from cultured GnRH-secreting neuronal cells cloned from human olfactory epithelium (FNC-B4), which showed biochemical and antigenic properties of GnRH-secreting neurons.
  
  
  METHODS
  FNC-B4 cells were cultured in basal and conditioned media.
  
  
  METHODS
  Reverse transcription-polymerase chain reaction (RTR-PCR) evaluated the expression of activin betaA-subunit mRNA. By using a specific ELISA, dimeric activin A concentrations were measured in culture media, in the absence or presence of carvone or forskolin and with different doses of progesterone, GnRH, and estradiol.
  
  
  RESULTS
  RT-PCR experiments performed on total RNA isolated from FNC-B4 cells, using specific primers for the activin betaA gene, showed a 787bp DNA band corresponding to the betaA gene. FNC-B4 cells secreted activin A, and the highest accumulation in conditioned medium was achieved after 3h culture: the addition of forskolin, but not of carvone, was able to stimulate the release of activin A from cultured neuronal cells (P<0.01). When progesterone or GnRH was added, a significant accumulation of activin A was observed (P<0.01), while estradiol administration did not significantly affect activin A secretion.
  
  
  CONCLUSIONS
  To date, this is the only study, in an in vitro human model reporting, that GnRH-secreting neuronal cells expressed activin betaA-subunit mRNA, and released dimeric activin A in culture medium. The expression and secretion of activin suggests that in these cells activin A might exert its action by autocrine/paracrine mechanisms.
authors.affiliation: Department of Reproductive Medicine and Child Development, Division of Obstetrics and Gynecology, University of Pisa, Pisa, Italy.
authors.forename: P
authors.initials: P
authors.lastname: Florio
authors.forename: G B
authors.initials: GB
authors.lastname: Vannelli
authors.forename: S
authors.initials: S
authors.lastname: Luisi
authors.forename: T
authors.initials: T
authors.lastname: Barni
authors.forename: R
authors.initials: R
authors.lastname: Zonefrati
authors.forename: C
authors.initials: C
authors.lastname: Falaschi
authors.forename: G
authors.initials: G
authors.lastname: Bifulco
authors.forename: A R
authors.initials: AR
authors.lastname: Genazzani
authors.forename: F
authors.initials: F
authors.lastname: Petraglia
mesh_terms: D028341:Activins; D002478:Cells, Cultured; D005576:Colforsin / Q000494:pharmacology; D000081005:Cyclohexane Monoterpenes; D019281:Dimerization; D004622:Embryo, Mammalian; D004958:Estradiol / Q000494:pharmacology; D015870:Gene Expression; D007987:Gonadotropin-Releasing Hormone / Q000378:metabolism* / Q000494:pharmacology; D006801:Humans; D007265:Inhibins / Q000235:genetics* / Q000378:metabolism*; D039821:Monoterpenes; D009474:Neurons / Q000378:metabolism*; D009831:Olfactory Mucosa; D011374:Progesterone / Q000494:pharmacology; D012333:RNA, Messenger / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013729:Terpenes / Q000494:pharmacology
chemical_list: D000081005:Cyclohexane Monoterpenes; D039821:Monoterpenes; D012333:RNA, Messenger; D013729:Terpenes; D028341:Activins; D005576:Colforsin; D007987:Gonadotropin-Releasing Hormone; D011374:Progesterone; D004958:Estradiol; D007265:Inhibins; C006923:carvone