Developmental eye abnormalities in mouse fetuses induced by retinoic acid

Area of Science:

• Developmental biology
• Ophthalmology
• Teratology

Background:

• Neural crest cells are crucial for craniofacial and ocular development.
• Retinoic acid is a known teratogen that can interfere with embryonic development.

Purpose of the Study:

• To investigate the impact of retinoic acid on neural crest cell migration and subsequent eye development.
• To characterize the spectrum of ocular malformations induced by retinoic acid exposure.

Main Methods:

• Pregnant mice received retinoic acid (RA) or corn oil (control) via intraperitoneal injection on day 7 of gestation.
• Fetal outcomes were assessed on day 18, including mortality, gross malformations, and detailed histological examination of the eyes.

Main Results:

• Retinoic acid exposure led to a 46.3% fetal mortality rate compared to 2.2% in controls.
• High incidences of microphthalmos (95.5%), cleft lip/palate (36.4%), and CNS anomalies (31.8%) were observed in the RA group.
• Histological analysis revealed various eye abnormalities in the RA group, such as anophthalmos (38.6%), faulty embryonic fissure closure (36.4%), and vitreous abnormalities (34.1%), all linked to abnormal neural crest cell migration.

Conclusions:

• Retinoic acid exposure during critical developmental periods disrupts neural crest cell migration, leading to severe ocular and craniofacial malformations.
• The study highlights the teratogenic potential of retinoic acid and its specific impact on eye development through neural crest cell pathways.