Early post-conception maternal cortisol, children's HPAA activity and DNA methylation profiles

Area of Science:

• Endocrinology
• Developmental Biology
• Epigenetics

Background:

• The hypothalamic-pituitary-adrenal axis (HPAA) is crucial for biological system regulation.
• Understanding environmental influences on HPAA development is key for health and disease origins.
• The early post-conception (EPC) period is critical as early exposures can affect all cell lineages.

Purpose of the Study:

• To investigate the relationship between maternal cortisol levels in the early post-conception period and children's pre-pubertal HPAA activity.
• To explore potential mediating roles of DNA methylation in this relationship.

Main Methods:

• Collected maternal first-morning urinary (FMU) cortisol every-other-day during the first 8 weeks post-conception (n=22 dyads).
• Assessed children's FMU cortisol and salivary cortisol responses to a challenge.
• Analyzed DNA methylation in children's buccal epithelial cells and its association with maternal EPC cortisol and children's HPAA activity.

Main Results:

• Maternal EPC FMU cortisol was associated with children's FMU cortisol and salivary cortisol responses.
• Children's HPAA activity was linked to five specific CpG sites.
• No CpG sites were associated with both maternal EPC cortisol and children's HPAA activity, indicating no mediation by these epigenetic changes.

Conclusions:

• Maternal cortisol during the early post-conception period is statistically linked to children's HPAA activity.
• The studied epigenetic modifications did not statistically mediate these observed physiological links.
• Larger prospective studies are needed to confirm findings and elucidate underlying biological mechanisms.