Summary
Maternal administration of 5-azacytidine to pregnant mice caused exencephaly in offspring. This developmental abnormality is linked to 5-azacytidine
Area of Science:
- Developmental biology
- Teratology
- Molecular toxicology
Background:
- Neural tube defects are a significant concern in human development.
- Understanding the molecular mechanisms underlying teratogen-induced birth defects is crucial.
Purpose of the Study:
- To investigate the teratogenic effects of 5-azacytidine on neural tube closure in mouse embryos.
- To elucidate the cellular mechanisms responsible for 5-azacytidine-induced exencephaly.
Main Methods:
- Maternal intraperitoneal administration of 5-azacytidine to pregnant S1c:ICR mice on gestational Day 7.5.
- Histological examination of mouse embryos at various developmental stages post-administration.
Main Results:
- A high incidence of exencephaly was observed in offspring exposed to 5-azacytidine.
- 5-azacytidine induced significant cell death (pyknotic cells) in the neurectoderm and mesoderm.
- Failure of head fold closure and neural tube closure was evident in treated embryos.
Conclusions:
- 5-azacytidine exposure during early gestation causes exencephaly in mice.
- The teratogenic effect is primarily attributed to the potent cell-killing action of 5-azacytidine on germinal cells.
- The exact molecular pathways leading to failed neural tube closure remain to be fully elucidated.
