Telomerase activity and apoptosis as indicators of ageing in placenta with and without intrauterine growth retardation.

Telomerase activity (TA) and apoptosis were analysed in placenta with and without intrauterine growth retardation (IUGR). Thirty-one specimens were taken from chorionic villi in the first trimester (Group A), 32 placenta specimens were obtained from cases without IUGR in second and third trimester (Group B) and 12 specimens of placenta tissue were obtained from cases of asymmetric IUGR between 26 and 39 weeks of gestation (Group C). TA was analysed by the Telomeric Repeat Amplification Protocol (TRAP) and in situ TRAP assay. Apoptotic changes were assessed by immunohistochemical staining using Bcl-2 monoclonal antibody and by terminal transferase-mediated in situ end-labelling (TUNEL). TA was detected in 29 of the 31 (93.5 per cent) chorionic villi (Group A) and in 20 of the 32 (62.5 per cent) placenta without IUGR (Group B), whereas weak TA was observed in the placenta of all 12 asymmetric IUGR cases (Group C). Significantly higher Bcl-2 immunoreactivity was observed in trophoblastic cells of Group A (85.9+/-4.2 per cent) and Group B (72.8+/-7.2 per cent) than Group C (54.84+/-4.83 per cent), while TUNEL positive cells were identified at a significantly higher frequency in the trophoblastic cells of Group C (9.7+/-7.4 per cent) than Group A (1.1+/-1.9 per cent) or Group B (2.9+/-3.7 per cent). Copyright 2000 Harcourt Publishers Ltd.