title: Telomere shortening in intra uterine growth restriction placentas.
abstract: BACKGROUND
  Placentas from pregnancies complicated with IUGR (intrauterine growth restriction) express altered telomere homeostasis. In the current study, we examined mechanisms of telomere shortening in these placentas.
  
  
  METHODS
  Placental biopsies from 15 IUGR and 15 healthy control pregnancies were examined. The percentage of trophoblasts with fragmented nuclei: senescence-associated heterochromatin foci (SAHF), was calculated using DAPI staining. The amount of human telomerase reverse transcriptase (hTERT) mRNA was evaluated using RtPCR levels of telomere capture using FISH in those samples were estimated.
  
  
  RESULTS
  The percentage of trophoblasts with SAHF was higher in IUGR compared to control samples, (25±13.4% vs. 1.6±1.6%, P<0.0001), hTERT mRNA was decreased (0.5±0.2 vs. 0.9±0.1, P<0.0001) and telomere capture was increased (13.2±9.7% vs.1.3±2.5%, P<0.001).
  
  
  CONCLUSIONS
  We suggest that IUGR placentas express increased signs of senescence as part of the impaired telomere homeostasis. One factor that mediates telomere shortening in these placentas is decreased hTERT mRNA, leading to decreased protein expression and therefore, reduced telomere elongation. Telomere capture, which is a healing process, is increased in IUGR trophoblasts as a compensatory mechanism.
authors.affiliation: Department of Obstetrics and Gynecology, Meir Medical Center, Kfar Saba, Israel; Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel. Electronic address: shentalt@inter.net.il.
authors.forename: Tal
authors.initials: T
authors.lastname: Biron-Shental
authors.affiliation: Department of Obstetrics and Gynecology, Meir Medical Center, Kfar Saba, Israel; Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel; Genetic Institute, Meir Medical Center, Kfar Saba, Israel.
authors.forename: Rivka
authors.initials: R
authors.lastname: Sukenik-Halevy
authors.affiliation: Genetic Institute, Meir Medical Center, Kfar Saba, Israel; Faculty of Life Science, Bar Ilan University, Ramat Gan, Israel.
authors.forename: Yudith
authors.initials: Y
authors.lastname: Sharon
authors.affiliation: Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel.
authors.forename: Ido
authors.initials: I
authors.lastname: Laish
authors.affiliation: Department of Obstetrics and Gynecology, Meir Medical Center, Kfar Saba, Israel; Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel; Genetic Institute, Meir Medical Center, Kfar Saba, Israel.
authors.forename: Moshe D
authors.initials: MD
authors.lastname: Fejgin
authors.affiliation: Genetic Institute, Meir Medical Center, Kfar Saba, Israel; Faculty of Life Science, Bar Ilan University, Ramat Gan, Israel.
authors.forename: Aliza
authors.initials: A
authors.lastname: Amiel
mesh_terms: D016022:Case-Control Studies; D005260:Female; D005317:Fetal Growth Retardation / Q000235:genetics* / Q000473:pathology; D006706:Homeostasis; D006801:Humans; D017404:In Situ Hybridization, Fluorescence; D020133:Reverse Transcriptase Polymerase Chain Reaction; D059506:Telomere Shortening
keywords: IUGR; Placenta; Senescence; Telomere; Telomere capture; Trophoblasts; hTERT