Source
School of Public Health, Fudan University, Shanghai 200032, China.
Abstract
OBJECTIVE:
To investigate the effect of environmental contaminants on development rate and DNA methyltransferase activity of preimplantation embryos.
METHODS:
1-cell embryos were collected from oviduct, in vitro cultured to blastocyst stage in media with or without environmental contaminants. The development rate and DNA methyltransferase activity were determined.
RESULTS:
The development rates of preimplantation embryos from 1-cell stage to blastocyst stage were not affected by the exposed compounds. However, 2, 3, 7, 8-tetrachlorodibenzo-p-dioxin (TCDD) significantly increased the DNA methyltransferase activity, 2, 2', 3, 3' 4, 4'-polychlorinated biphenyl (PCB153) and diethylstilbestrol (DES) significantly decreased the DNA methyltransferase activity, while p, p'- dichlorodiphenel ethylene (DDE) and dibutyl phthalate (DBP) did not change the DNA methyltransferase activity significantly.
CONCLUSION:
Exposure to TCDD, DES, and PCB 153 alters the DNA methyltransferase activity in early development stage, which may induce the change of methylation status of genes and affect the development in the later stage.