title: Progesterone inhibits in vitro fetal membrane weakening.
abstract: OBJECTIVE
  Inflammation/infection and abruption are leading causes of preterm premature rupture of the membranes. Recently, we identified granulocyte-macrophage colony-stimulating factor (GM-CSF) as a critical mediator of both tumor necrosis factor-α- (TNF; modeling inflammation) and thrombin-induced (modeling abruption) weakening of the fetal membranes. We found that (1) TNF and thrombin both induced GM-CSF in the choriodecidua, (2) blockade of GM-CSF action with neutralizing antibodies inhibited both TNF- and thrombin-induced fetal membrane weakening, and (3) GM-CSF alone induced fetal membrane weakening. GM-CSF is thus part of an overlap of the inflammation and abruption-induced fetal membrane weakening pathways. The effects of progesterone analogs on the pathways by which fetal membranes are weakened have not been investigated. We examined the effects of progesterone, medroxyprogesterone acetate (MPA) and 17α-hydroxyprogesterone (HP) on TNF- and thrombin-induced fetal membrane weakening.
  
  
  METHODS
  Full-thickness fetal membranes from uncomplicated term repeat cesarean deliveries were mounted in Transwell inserts in Minimum Essential Medium alpha and incubated at 37°C in 5% CO2. The choriodecidua side of the fetal membrane fragments were preincubated with progesterone, MPA, HP, or vehicle for 24 hours. Fetal membranes were then exposed to TNF, thrombin, or GM-CSF on the choriodecidua side for an additional 48 hours. The fetal membrane tissues were then strength tested, and medium from the choriodecidua and amnion compartments was assayed for GM-CSF content.
  
  
  RESULTS
  TNF and thrombin both weakened fetal membranes and elevated media GM-CSF levels on the choriodecidua side of the fetal membrane. Pretreatment with progesterone, MPA, or HP inhibited both TNF- and thrombin-induced fetal membrane weakening and also inhibited the induced increase in GM-CSF. GM-CSF decreased fetal membrane rupture strength by 68%, which was inhibited by progestogen pretreatment with a potency order: progesterone <MPA <HP.
  
  
  CONCLUSIONS
  Progestogen pretreatment blocks TNF- and thrombin-induced fetal membrane weakening by inhibiting both the production and action of GM-CSF. These findings are consistent with the administration of progestogens in the prevention of preterm premature rupture of the membranes.
authors.affiliation: Department of Pediatrics, Case Western Reserve University, Cleveland, OH.
authors.forename: Deepak
authors.initials: D
authors.lastname: Kumar
authors.affiliation: Department of Reproductive Biology, Case Western Reserve University, Cleveland, OH.
authors.forename: Edward
authors.initials: E
authors.lastname: Springel
authors.affiliation: Department of Pediatrics, Case Western Reserve University, Cleveland, OH.
authors.forename: Robert M
authors.initials: RM
authors.lastname: Moore
authors.affiliation: Department of Reproductive Biology, Case Western Reserve University, Cleveland, OH.
authors.forename: Brian M
authors.initials: BM
authors.lastname: Mercer
authors.affiliation: Women's Health Institute, Cleveland Clinic, Cleveland, OH.
authors.forename: Elliot
authors.initials: E
authors.lastname: Philipson
authors.affiliation: Department of Mechanical and Aerospace Engineering, Case Western Reserve University, Cleveland, OH.
authors.forename: Joseph M
authors.initials: JM
authors.lastname: Mansour
authors.affiliation: Department of Reproductive Biology, Case Western Reserve University, Cleveland, OH.
authors.forename: Sam
authors.initials: S
authors.lastname: Mesiano
authors.affiliation: Department of Obstetrics and Gynecology, University of South Florida College of Medicine, Tampa, FL.
authors.forename: Fredrick
authors.initials: F
authors.lastname: Schatz
authors.affiliation: Department of Obstetrics and Gynecology, University of South Florida College of Medicine, Tampa, FL.
authors.forename: Charles J
authors.initials: CJ
authors.lastname: Lockwood
authors.affiliation: Department of Pediatrics, Case Western Reserve University, Cleveland, OH; Department of Reproductive Biology, Case Western Reserve University, Cleveland, OH. Electronic address: jmoore@metrohealth.org.
authors.forename: John J
authors.initials: JJ
authors.lastname: Moore
mesh_terms: D019326:17-alpha-Hydroxyprogesterone / Q000494:pharmacology; D002823:Chorion / Q000187:drug effects*; D003656:Decidua / Q000187:drug effects*; D005321:Extraembryonic Membranes / Q000187:drug effects; D005260:Female; D005322:Premature Rupture of Fetal Membranes; D016178:Granulocyte-Macrophage Colony-Stimulating Factor / Q000494:pharmacology*; D006490:Hemostatics / Q000494:pharmacology*; D006801:Humans; D066298:In Vitro Techniques; D017258:Medroxyprogesterone Acetate / Q000494:pharmacology; D011247:Pregnancy; D011374:Progesterone / Q000494:pharmacology*; D011372:Progestins / Q000494:pharmacology*; D013917:Thrombin / Q000494:pharmacology*; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology*
chemical_list: D006490:Hemostatics; D011372:Progestins; D014409:Tumor Necrosis Factor-alpha; D011374:Progesterone; D019326:17-alpha-Hydroxyprogesterone; D016178:Granulocyte-Macrophage Colony-Stimulating Factor; D017258:Medroxyprogesterone Acetate; D013917:Thrombin
keywords: GM-CSF; PPROM; TNF; fetal membrane; medroxyprogesterone acetate; progesterone; thrombin; weakening