
Exposure to high levels of the body’s primary stress hormone – cortisol – in preterm fetuses can disrupt normal heart development, potentially increasing the risk of cardiovascular disease in later life.
That’s the finding from a new study led by the University of South Australia (UniSA), showing that elevated cortisol levels in preterm lambs significantly alters molecules that control proper heart development.
The findings, published in Experimental Physiology, offer vital insights into how early life stress may influence heart health in later life and could help inform how corticosteroids are used in pregnancy.
Lead author Professor Janna Morrison, Head of the Early Origins of Adult Health Research Group at UniSA, says preterm birth is a leading cause of neonatal mortality and is associated with an increased risk of cardiovascular disease in adults.
Pregnancy complications such as gestational diabetes, preeclampsia, obesity and placental insufficiency can lead to a premature increase in cortisol concentrations earlier in gestation that impacts the developing fetus.
To mimic the cortisol levels that are normal in late gestation, researchers administered cortisol to preterm sheep fetuses over seven days and then studied the impact on signalling molecules in the heart.
The results showed significant changes in the heart’s molecular structure.
Co-lead on the project, Dr Mitchell Lock, says that while antenatal corticosteroids remain critical for improving survival, our research highlights the importance of closely monitoring their use in pregnancy.
“We hope these findings will also help refine the clinical care of preterm babies to support better long-term outcomes.”
Reference
1) https://physoc.onlinelibrary.wiley.com/doi/10.1113/EP092506
(Newswise/HB)