Scientists today hailed a “major breakthrough” after discovering a major potential treatment for postpartum depression.
Until now, experts were unsure what exactly triggers the condition, even though one in ten women is affected before or after giving birth.
But researchers in the US and UK have discovered that those affected may lack genes that allow the body to produce the hormone oxytocin.
Oxytocin, known as the “cuddle hormone,” is released during childbirth, breastfeeding, and in response to hugs, helping to stimulate feelings of attachment.
Without enough, new mothers can struggle to bond with their baby, leading to low mood. Now, experts suggest that the development of new oxytocin drugs may be a way to help combat these symptoms.
Until now, experts were unsure of what exactly triggers postpartum depression. But researchers in the US and UK have discovered that some women may lack the gene that helps them produce oxytocin, often called the “cuddle hormone.”
Professor Sadaf Farooqi, from the Institute of Metabolic Sciences at the University of Cambridge: ‘We have made a major breakthrough in understanding postnatal depression, a serious health problem about which very little is known despite many decades of research.
‘More importantly, it may indicate that oxytocin is a possible treatment for some mothers with this condition.
‘This research reminds us that many behaviors we assume are entirely under our control have a solid biological basis.’
The researchers, led by scientists at the University of Cambridge and Baylor College of Medicine in Texas, made their discovery while looking at the genes of two children from different families.
Both were severely obese and also suffered from anxiety, autism and behavioral problems.
They found that each of them was missing a single gene known as TRPC5.
Their mothers also lacked the gene. Both were obese and had suffered from postpartum depression.
When examining the missing gene in mouse studies, scientists found that male mice with a defective form of the gene had the same problems as boys.
These included weight gain, anxiety, aversion to social interactions, and aggressive behavior.
Female mice showed similar behaviors.
And when they became mothers, they also displayed depressive behavior and “poor child care,” the experts said.
Writing in the diary CellThe researchers said they found that TRPC5 acts on nerve cells that produce the hormone oxytocin.
Deleting the TRPC5 gene from these oxytocin neurons caused otherwise healthy mice to show signs of anxiety, overeating, impaired social skills and, in the mothers, symptoms similar to postpartum depression.
By making changes to the TRPC5 gene to produce more oxytocin, the scientists “reversed” these symptoms: the mice began to behave normally and lost weight.
Experts suggest that treatments that help increase oxytocin in the body could produce similar results in humans, although more research is needed.
Oxytocin is produced in the hypothalamus, part of the brain, and secreted into the bloodstream by the pituitary gland.
Studies have shown that oxytocin may also have anxiolytic properties, meaning it can help reduce anxiety.
Previous researchers had also found that when oxytocin is given to people with autism via a nasal spray, it makes them more sociable.
Causes of postpartum depression intense feelings of sadness, anxiety and exhaustion that usually begin two to three days after delivery and can last for months.
Other symptoms include insomnia, loss of appetite, intense irritability, and difficulty bonding with the baby.
In rare cases, an extreme disorder called postpartum psychosis can develop.
Existing treatment includes talk therapy or traditional antidepressants, but these can take weeks to take effect.
The latest NHS data shows that 26 per cent of adults in England are obese and a further 38 per cent are overweight but not obese.
Experts have pointed to a lack of exercise and poor diets high in ultra-processed foods as the main drivers of the UK’s obesity epidemic.
Dr. Yong Xu, a molecular and cellular biology expert at Baylor College of Medicine, said: “What we saw in those mice was quite remarkable.
“They showed behaviors very similar to those observed in people who lacked the TRPC5 gene, which in mothers included symptoms of depression and difficulty caring for their babies. This shows us that this gene is the one that causes these behaviors.”
Professor Farooqi added: ‘There is a reason why people who lack TRPC5 develop all these conditions.
‘Our work shows that TRPC5 acts on oxytocin neurons in the hypothalamus and plays a key role in regulating our instincts.’