Related Experiment Videos
Embryotoxicity of 5-azacytidine in mice. Phase- and dose-specificity studies
Abstract:
The agent 5-azacytidine, which directly affects nucleic acid metabolism, is a potent teratogen in NMRI mice. The establishment of general teratological data revealed clear-cut dose-response relationships after administration of this agent on either day 12 or day 14 of gestation. Inspection of skeletal abnormalities revealed a clear-cut phase specificity of this drug when administered on days 10 or 11 of pregnancy. Additional histological studies showed that central nervous system anomalies were induced mainly after administration of azacytidine on days 10, 11, 12, or 13 of pregnancy. A most conspicuous finding was the formation of anomalous glioblast islets within the ventricular zone covering the basal ganglia. The latter malformation mainly occurred after treatment on day 11 or 12 of pregnancy. Another important malformation syndrome was the appearance of capillary ectasias and hind paw hematomas, together with an intense necrotic cardiomyopathy after treatment on either day 11 or 12 of gestation.
Insights
The drug 5-azacytidine is a potent teratogen in mice, causing dose-dependent birth defects. Specific developmental stages are vulnerable to its effects, leading to central nervous system and skeletal abnormalities.
Area of Science:
- Developmental toxicology
- Teratology
- Pharmacology
Background:
- 5-azacytidine affects nucleic acid metabolism.
- It is a known potent teratogen in NMRI mice.
Purpose of the Study:
- To establish general teratological data for 5-azacytidine.
- To determine dose-response relationships and phase specificity of teratogenic effects.
- To investigate specific malformations induced by 5-azacytidine.
Main Methods:
- Administration of 5-azacytidine to pregnant NMRI mice on specific gestation days (10, 11, 12, 14).
- Evaluation of skeletal abnormalities.
- Histological examination of central nervous system anomalies.
- Assessment of cardiovascular and limb malformations.
Main Results:
- Clear dose-response relationships observed for administration on days 12 and 14.
- Phase-specific skeletal abnormalities occurred with administration on days 10 and 11.
- Central nervous system anomalies were induced by administration on days 10-13.
- Anomalous glioblast islets formed after treatment on days 11 and 12.
- Capillary ectasias, hind paw hematomas, and necrotic cardiomyopathy observed after treatment on days 11 and 12.
Conclusions:
- 5-azacytidine exhibits clear dose-response and phase-specific teratogenic effects in mice.
- Specific developmental windows (days 10-13) are critical for CNS anomaly induction.
- Distinct malformation syndromes, including CNS and cardiovascular defects, are associated with 5-azacytidine exposure.