How prenatal environmental factors affect rat molar enamel formation?

Area of Science:

• Developmental Biology
• Oral Biology
• Toxicology

Background:

• Amelogenin (AMELX) and ameloblastin (AMBN) are essential enamel matrix proteins.
• Disruptions in AMELX and AMBN production can lead to enamel defects.
• Prenatal environmental factors are potential disruptors of normal tooth development.

Purpose of the Study:

• To investigate the impact of prenatal exposure to chronic stress, bisphenol A (BPA), amoxicillin, and lipopolysaccharide (LPS) on AMELX and AMBN production in ameloblasts.
• To evaluate the effects of these environmental factors on enamel matrix formation and morphology.

Main Methods:

• Pregnant Sprague-Dawley rats were exposed to chronic stress, BPA, amoxicillin, or LPS during gestation.
• Ameloblasts from offspring were analyzed for AMELX and AMBN protein expression using immunohistochemistry.
• Enamel matrix formation and morphology were assessed using H&E and Gomori's trichrome staining, and stereomicroscopy.

Main Results:

• All experimental groups showed significantly reduced AMELX and AMBN staining intensity compared to the control group across secretory, transitional, and maturation stages.
• Abnormal enamel matrix formation was observed in all experimental groups.
• The amoxicillin group exhibited yellowish coloration in morphologic evaluation.

Conclusions:

• Prenatal exposure to chronic stress, BPA, amoxicillin, and LPS adversely affects ameloblast function and enamel matrix production.
• These environmental factors can lead to developmental enamel defects.
• Further research is warranted to understand the long-term implications and mechanisms of these prenatal exposures on dental health.