title: Withdrawal of ovarian steroids stimulates prostaglandin F2alpha production through nuclear factor-kappaB activation via oxygen radicals in human endometrial stromal cells: potential relevance to menstruation.
abstract: The present study was undertaken to investigate whether withdrawal of estrogen and progesterone (EP-withdrawal) stimulates prostaglandin F2alpha (PGF2alpha) production through oxygen radical (ROS)-induced NF-kappaB activation in human endometrial stromal cells (ESC). To study the EP-withdrawal, ESC that had been treated with estradiol (E, 10(-8) M) and medroxyprogesterone acetate (MPA, 10(-6) M) for 12 days were then incubated with or without E+MPA for a further 11 days. PGF2alpha concentrations in the medium and cyclooxygenase-2 (COX-2) mRNA levels were significantly increased after EP-withdrawal, while they were unchanged by the continuous treatment with E+MPA. When ESC were incubated with N-acetyl-L-cysteine (Nac, 50 mM), an antioxidant, during EP-withdrawal, Nac blocked the increases in PGF2alpha production and COX-2 mRNA expression caused by EP-withdrawal. Next, we examined whether ROS generated in response to EP-withdrawal acted through NF-kappaB activation. Electrophoretic mobility shift assay revealed that EP-withdrawal caused marked increases in NF-kappaB DNA binding activity, which was completely suppressed by Nac. Furthermore, when ESC were incubated with MG132 (3 microM), which inhibits NF-kappaB activation, during EP-withdrawal, MG132 blocked the increases in PGF2alpha production and COX-2 mRNA expression caused by EP-withdrawal. In conclusion, EP-withdrawal stimulates COX-2 expression and PGF2alpha production through ROS-induced NF-kappaB activation, suggesting a possible mechanism for menstruation.
authors.affiliation: Division of Obstetrics and Gynecology, Department of Reproductive, Pediatric and Infectious Science, Yamaguchi University School of Medicine, Ube, Japan. sugino@yamaguchi-u.a.cjp
authors.forename: Norihiro
authors.initials: N
authors.lastname: Sugino
authors.forename: Ayako
authors.initials: A
authors.lastname: Karube-Harada
authors.forename: Toshiaki
authors.initials: T
authors.lastname: Taketani
authors.forename: Aki
authors.initials: A
authors.lastname: Sakata
authors.forename: Yasuhiko
authors.initials: Y
authors.lastname: Nakamura
mesh_terms: D000111:Acetylcysteine / Q000378:metabolism / Q000494:pharmacology; D000328:Adult; D000975:Antioxidants / Q000494:pharmacology; D002478:Cells, Cultured; D051546:Cyclooxygenase 2; D003546:Cysteine Endopeptidases; D015237:Dinoprost / Q000378:metabolism*; D004717:Endometrium / Q000473:pathology; D004789:Enzyme Activation; D004958:Estradiol / Q000378:metabolism; D005260:Female; D005609:Free Radicals; D006801:Humans; D007527:Isoenzymes / Q000378:metabolism; D007976:Leupeptins / Q000494:pharmacology; D017258:Medroxyprogesterone Acetate / Q000378:metabolism; D008565:Membrane Proteins; D008598:Menstruation; D009097:Multienzyme Complexes / Q000037:antagonists & inhibitors; D016328:NF-kappa B / Q000378:metabolism*; D010053:Ovary / Q000166:cytology / Q000378:metabolism*; D010100:Oxygen / Q000378:metabolism*; D011374:Progesterone / Q000378:metabolism; D011451:Prostaglandin-Endoperoxide Synthases / Q000378:metabolism; D046988:Proteasome Endopeptidase Complex; D012313:RNA / Q000378:metabolism; D012333:RNA, Messenger / Q000378:metabolism; D017382:Reactive Oxygen Species; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013256:Steroids / Q000502:physiology*; D017154:Stromal Cells / Q000166:cytology*; D013482:Superoxide Dismutase / Q000378:metabolism; D013481:Superoxides / Q000378:metabolism; D013997:Time Factors
chemical_list: D000975:Antioxidants; D005609:Free Radicals; D007527:Isoenzymes; D007976:Leupeptins; D008565:Membrane Proteins; D009097:Multienzyme Complexes; D016328:NF-kappa B; D012333:RNA, Messenger; D017382:Reactive Oxygen Species; D013256:Steroids; D013481:Superoxides; D011374:Progesterone; D004958:Estradiol; D012313:RNA; D015237:Dinoprost; D017258:Medroxyprogesterone Acetate; D051546:Cyclooxygenase 2; C496540:PTGS2 protein, human; D011451:Prostaglandin-Endoperoxide Synthases; D013482:Superoxide Dismutase; D003546:Cysteine Endopeptidases; D046988:Proteasome Endopeptidase Complex; C072553:benzyloxycarbonylleucyl-leucyl-leucine aldehyde; D010100:Oxygen; D000111:Acetylcysteine