A study carried out by researchers from Inserm and the University of Grenoble Alpes has highlighted the vulnerability of the placenta to air pollution.
Air pollution represents a “major risk for the smooth progress of pregnancy”. This is what researchers from Inserm and the University of Grenoble Alpes say in a new study published this Tuesday, May 7 in the journal The Lancet Planetary Health.
According to them, exposure to outdoor air pollution is “suspected of being the cause of cardio-metabolic, respiratory or even neuropsychological pathologies in the unborn child”, they wrote in a communicated.
The placenta seen as an “archive”
The study was based on data obtained from nearly 1,500 pregnant women in France. Scientists then became interested in epigenetic modifications – which induce changes in gene expression – of the placenta, seen as an “archive” of a child’s prenatal environment because it is “particularly vulnerable to many chemical compounds”.
According to the study, a third of placental changes are associated with indicators of child development such as birth weight and height, head circumference or duration of pregnancy.
“Other placental modifications concerned genes involved in the development of the nervous system, the immune system and metabolism – including genes involved in the occurrence of neonatal diabetes or obesity,” added Inserm.
Gender disparities
In addition to these visible changes for both sexes, researchers have highlighted more vulnerable gestation periods depending on the gender of the child: the first trimester in boys and the third trimester in girls.
For boys, air pollution can alter genes involved in the development of the nervous system and intellect. While for girls, the affected genes are involved in fetal development and the regulation of oxidative stress.
Inserm then explained: “They could thus be associated with developmental defects likely to increase the risks of developing chronic metabolic diseases (hypertension, diabetes, obesity, etc.) later in life, but also with the occurrence of miscarriage or pre-eclampsia in the mother.”
Now, researchers are trying to understand the molecular mechanisms behind these modifications. They also hope that new studies will analyze the influence of these placental epigenetic changes after childbirth and their development during childhood.
