Objective: Telomeres are nucleoprotein structures consisted of repeats of the DNA sequence TTAGGG that are located at the termini of chromosomes, and protect the chromosomes from fusion and degradation. Telomeres are progressively shortened with each mitotic cycle and also by environmental factors. We hypothesized that antepartum stress can lead to accelerated telomeres shortening in placental trophoblasts, which affects placental functioning and plays a role in intrauterine growth restriction (IUGR).
Methods: Placental biopsies derived from 16 pregnancies complicated with IUGR and from 13 gestational age matched placentas from uncomplicated pregnancies as control. Slides from the placental biopsies were subjected to a fluorescence-in-situ protocol (DAKO) to determine telomere fluorescence intensity and number. To rule out aneuploidity as a reason for shortened telomeres we used fluorescence-in-situ-hybridization for chromosomes 16, 18, X and y.
Results: We found that the number and intensity of telomeres staining was significantly lower in the IUGR placentas compared to the controls as shown in the attached table. No aneuploidity was detected for the chromosomes checked in either of the placental biopsies.
Conclusions: Telomeres are shorter in trophoblasts of IUGR placentas. Our findings implicate short telomeres as a mechanism of early senescence in IUGR placentas regardless the ploidity of the cells.
Mean number of cells in the different categories of signal intensity
(low, high) /telomere number (≤10, ≥10)
Authors
Tal Biron-Shentala,d, Rebeka Sukenik Halevi, Lilach Goldberg-Bittmanb,c, Devora Kidron, Moshe D. Fejginb,d, Alisa Amielb,c
aOBGYN ward bGenetic Institute, Meir Hospital, Kfar-Saba, cFaculty of Life Science, Bar-Ilan University, Ramat Gan, dSackler School of Medicine, Tel Aviv University, Tel Aviv
Mean number of cells in the different categories of signal intensity
(low, high) /telomere number (≤10, ≥10)