Researchers have unveiled some of the mechanisms that play a major role in the sudden onset of anxiety and depression in adulthood.
Exposure to stress while in the womb is a known factor that increases risks of anxiety and depression in the offspring. In most cases, the placenta protects babies against being exposed to their mother's stress hormones.
However, according to Professor Jonathan Seckl and colleagues from the Weizmann Institute of Science in Israel, the basic component of placenta that executes the role is sometimes damaged, hence passing on the stress from the mother to the baby, The Telegraph reported.
The stress hormone that reaches the baby's brain alterations some genes in the fetus, placing it at higher risks of developing depression, anxiety or conditions like attention deficit hyperactivity disorder (ADHD), after birth.
"There is an enzyme found in high levels in the placenta and the baby's brain. It seems to be a natural barrier to stress hormones and it deactivates them," Professor Seckl, an endocrinologist at the Queen's Medical Research Institute at the University of Edinburgh, told The Telegraph. "If you inhibit this barrier then you start to get children with a low birth weight who have altered stress responses and depression. This may be what underpins the variation you get from one individual to another."
While trying to identify the reasons, researchers found two main factors playing major roles- excess intake of liquorice in pregnancy and absence of the protective enzyme in the mother. According to them, eating a bag of liquorice daily is enough to increase the risks of giving birth early and having children with ADHD or other anxiety disorders.
The scientists reached their conclusion by conducting experiments on pregnant rats. Apart from that, researchers also found that exposure to mother's stress during final stages of pregnancy left a negative impact on a child's stress response system.
Concerned with their findings, Seckl and his team are currently trying to develop tests that can help identify children that are more vulnerable to the mother's stress exposure.
