Mom's dietary fat rewires male and female brains differently

According to statistics, it is said that more than half of all women are overweight or obese when they become pregnant. While being or becoming overweight during pregnancy can have potential health risks for moms, there are also hints that it may tip the scales for their kids to develop psychiatric disorders like autism or depression, which often affects one gender more than the other.

In findings in the journal Nature Metabolism, the researchers have found that mom's high-fat diet triggers immune cells in the developing brains of males to overconsume the mood-influencing brain chemical serotonin, leading to depressed-like behavior.

People with mood disorders like depression often lose interest in pleasurable activities. For mice, one innately pleasurable activity is drinking sugar water. Since mice preferentially sip sugar water over plain tap when given the choice, researchers measured their drink preference as an estimate for depression.

Males, but not females, born by moms on a high-fat diet lacked a preference for simple syrup over tap water. This rodent-like depression suggested to researchers that mom's nutrition while pregnant must have changed their male offspring's brain during development.

One immediate suspect was serotonin. Often called the "happy" chemical, serotonin is a molecular brain messenger that's typically reduced in people with depression.

Researchers found that depressed-like male mice from high-fat diet moms had less serotonin in their brain both in the womb and as adults, suggesting these early impacts have lifelong consequences.

This research highlights that not all placentas are created equally. This work may one day help guide clinicians and parents in better understanding and possible treatment or prevention of the origins of some mood disorders by considering early environmental factors, like fat accumulation during gestation.

Reference:

Mom's dietary fat rewires male and female brains differently; Nature Metabolism, DOI:10.1038/s42255-022-00693-8.