Poor Mental Health in Adulthood Triggered in the Womb
Hormonal imbalances in the placenta has been linked to anxiety, vulnerability and poor mental health in mice.
The latest findings suggest that adults could be at greater risk of becoming anxious and vulnerable if they are deprived of certain hormones while developing in the womb.
The study is the first to link changes in adult behavior to alterations in placental function. Researchers at Cardiff and Cambridge universities also showed the role of the placenta in long-term programming of emotional behavior.
Insulin-like growth factor-2 plays a major role in fetal and placental development in mammals, and changes in expression of this hormone in the placenta and fetus are implicated in growth restriction in the womb.
"The growth of a baby is a very complex process and there are lots of control mechanisms which make sure that the nutrients required by the baby to grow can be supplied by the mother," lead researcher Professor Lawrence Wilkinson, a behavioral neuroscientist from Cardiff University's School of Psychology, said in a news release. "We were interested in how disrupting this balance could influence emotional behaviors a long time after being born, as an adult."
Researchers said they examined how a mismatch between supply and demand of certain nutrients might affect humans by examining the behavior of adult mice with a malfunctioned supply of Insulin-like growth factor-2.
"We achieved this by damaging a hormone called Insulin-like growth factor-2, important for controlling growth in the womb. What we found when we did this was an imbalance in the supply of nutrients controlled by the placenta, and that this imbalance had major effects on how subjects were during adulthood - namely, that subject became more anxious later in life," Humby added,
"These symptoms were accompanied by specific changes in brain gene expression related to this type of behavior. This is the first example of what we have termed 'placental-programming' of adult behavior. We do not know exactly how these very early life events can cause long-range effects on our emotional predispositions, but we suspect that our research findings may indicate that the seeds of our behavior, and possibly vulnerability to brain and mental health disorders, are sown much earlier than previously thought," he concluded.
Researchers said the latest mouse study might have wider implications for human development. Humby saud the next step us to study the brain mechanisms linking early life events, placental dysfunction and the emotional state of adults.