The placental transcriptome serves as a mechanistic link between prenatal phthalate exposure and placental efficiency

Area of Science:

• Environmental Health
• Genomics
• Reproductive Biology

Background:

• Phthalates are endocrine-disrupting chemicals linked to adverse child health outcomes like prematurity.
• Placental transcriptomics offers insights into how environmental toxicants affect placental and fetal development.
• Understanding these mechanisms is crucial for mitigating prenatal exposure risks.

Purpose of the Study:

• To investigate the placental transcriptome's role in mediating the association between maternal urinary phthalate metabolites and placental efficiency.
• To identify specific genes and gene modules involved in this mediation pathway.
• To elucidate the biological processes affected by phthalate exposure during pregnancy.

Main Methods:

• Analysis of maternal urinary phthalate metabolite concentrations.
• Utilized placental transcriptomics data to identify gene and gene module expression.
• Modeled placental efficiency using birthweight to placental weight ratio (BW:PW) and adjusted birthweight (BWadj).
• Employed mediation analysis to assess the role of the placental transcriptome.

Main Results:

• Significant associations were found between maternal phthalate metabolites and 132 genes/27 gene modules in the placenta.
• Placental efficiency measures were significantly associated with 460 genes/11 gene modules.
• Four genes and nine gene modules significantly mediated the relationship between phthalates and placental efficiency.
• Mediating genes are involved in critical placental functions like syncytialization, metabolism, and steroid biosynthesis.

Conclusions:

• The placental transcriptome plays a key mediating role in how phthalates disrupt fetal growth.
• These findings highlight specific molecular pathways affected by prenatal phthalate exposure.
• This research provides a mechanistic link between environmental toxicants and adverse birth outcomes.