title: Loss of Thrombomodulin in Placental Dysfunction in Preeclampsia.
abstract: OBJECTIVE
  Preeclampsia is a pregnancy-specific syndrome characterized by placental dysfunction and an angiogenic imbalance. Systemically, levels of thrombomodulin, an endothelium- and syncytiotrophoblast-bound protein that regulates coagulation, inflammation, apoptosis, and tissue remodeling, are increased. We aimed to investigate placental thrombomodulin dysregulation and consequent downstream effects in the pathogenesis of preeclampsia.
  
  
  RESULTS
  Placentas from 28 preeclampsia pregnancies, 30 uncomplicated pregnancies, and 21 pregnancies complicated by growth restriction as extra controls were included. Immunohistochemical staining of thrombomodulin, caspase-3, and fibrin was performed. Placental mRNA expression of thrombomodulin, inflammatory markers, matrix metalloproteinases 2 and 9, and soluble Flt-1 were measured with quantitative polymerase chain reaction. Thrombomodulin mRNA expression was determined in vascular endothelial growth factor-transfected trophoblast cell lines. Thrombomodulin protein and mRNA expression were decreased in preeclampsia as compared with both control groups (P=0.001). Thrombomodulin mRNA expression correlated with maternal body mass index (P<0.01) and diastolic blood pressure (P<0.05) in preeclampsia. An increase in placental apoptotic cells was associated with preeclampsia (P<0.001). Thrombomodulin expression correlated positively with matrix metalloproteinase expression (P<0.01) in preeclampsia, but not with fibrin deposits or inflammatory markers. Placental soluble Flt-1 expression correlated with decreased thrombomodulin expression. Vascular endothelial growth factor induced upregulation of thrombomodulin expression in trophoblast cells.
  
  
  CONCLUSIONS
  Decreased thrombomodulin expression in preeclampsia may play a role in placental dysfunction in preeclampsia and is possibly caused by an angiogenic imbalance. Hypertension and obesity are associated with thrombomodulin downregulation. These results set the stage for further basic and clinical research on thrombomodulin in the pathogenesis of preeclampsia and other syndromes characterized by endothelial dysfunction.
authors.affiliation: From the Departments of Pathology (R.J.T., J.A.B., H.J.B.) and Obstetrics (K.W.M.B.), Leiden University Medical Centre, Leiden, the Netherlands; and Department of Obstetrics, Birth Centre, Wilhelmina Children Hospital, Division Woman and Baby, University Medical Centre Utrecht, Utrecht, the Netherlands (K.W.M.B.). r.j.turner@lumc.nl.
authors.forename: Rosanne J
authors.initials: RJ
authors.lastname: Turner
authors.affiliation: From the Departments of Pathology (R.J.T., J.A.B., H.J.B.) and Obstetrics (K.W.M.B.), Leiden University Medical Centre, Leiden, the Netherlands; and Department of Obstetrics, Birth Centre, Wilhelmina Children Hospital, Division Woman and Baby, University Medical Centre Utrecht, Utrecht, the Netherlands (K.W.M.B.).
authors.forename: Kitty W M
authors.initials: KW
authors.lastname: Bloemenkamp
authors.affiliation: From the Departments of Pathology (R.J.T., J.A.B., H.J.B.) and Obstetrics (K.W.M.B.), Leiden University Medical Centre, Leiden, the Netherlands; and Department of Obstetrics, Birth Centre, Wilhelmina Children Hospital, Division Woman and Baby, University Medical Centre Utrecht, Utrecht, the Netherlands (K.W.M.B.).
authors.forename: Jan A
authors.initials: JA
authors.lastname: Bruijn
authors.affiliation: From the Departments of Pathology (R.J.T., J.A.B., H.J.B.) and Obstetrics (K.W.M.B.), Leiden University Medical Centre, Leiden, the Netherlands; and Department of Obstetrics, Birth Centre, Wilhelmina Children Hospital, Division Woman and Baby, University Medical Centre Utrecht, Utrecht, the Netherlands (K.W.M.B.).
authors.forename: Hans J
authors.initials: HJ
authors.lastname: Baelde
mesh_terms: D000328:Adult; D017209:Apoptosis; D053148:Caspase 3 / Q000378:metabolism; D002460:Cell Line; D015536:Down-Regulation; D005260:Female; D005337:Fibrin / Q000378:metabolism; D006801:Humans; D018836:Inflammation Mediators / Q000378:metabolism; D020782:Matrix Metalloproteinases / Q000378:metabolism; D010920:Placenta / Q000378:metabolism* / Q000473:pathology / Q000503:physiopathology; D011225:Pre-Eclampsia / Q000175:diagnosis / Q000235:genetics / Q000378:metabolism* / Q000503:physiopathology; D011247:Pregnancy; D012333:RNA, Messenger / Q000378:metabolism; D015398:Signal Transduction; D018180:Thrombomodulin / Q000235:genetics / Q000378:metabolism*; D014162:Transfection; D014327:Trophoblasts / Q000378:metabolism / Q000473:pathology; D042461:Vascular Endothelial Growth Factor A / Q000235:genetics / Q000378:metabolism; D040281:Vascular Endothelial Growth Factor Receptor-1 / Q000378:metabolism
chemical_list: D018836:Inflammation Mediators; D012333:RNA, Messenger; C546931:THBD protein, human; D018180:Thrombomodulin; D042461:Vascular Endothelial Growth Factor A; D005337:Fibrin; C501162:FLT1 protein, human; D040281:Vascular Endothelial Growth Factor Receptor-1; C505407:CASP3 protein, human; D053148:Caspase 3; D020782:Matrix Metalloproteinases
keywords: angiogenesis; coagulation; hypertension; preeclampsia/pregnancy; thrombomodulin