Smoking during pregnancy affects myelin genes in offspring
Smoking during pregnancy may interfere with brain development. New animal research shows maternal smoking affects genes important in the formation and action of a fatty brain substance called myelin that insulates brain cell connections.
The research was presented at Neuroscience 2010, the annual meeting of the Society for Neuroscience, held in San Diego.
The finding may explain why the children of mothers who smoked during pregnancy are more likely to develop attention deficit hyperactivity disorder, depression, autism, drug abuse, and other psychiatric disorders. ‘Myelin deficits have been previously observed in adults with various psychiatric disorders,’ said Ming Li, PhD, of the University of Virginia, who directed the study. ‘Our findings suggest that abnormal myelination may also contribute to the psychiatric disorders associated with maternal smoking,’ Li said.
The study found that when rats were given nicotine during pregnancy, their offspring showed changes in myelin genes in specific regions of their brain’s limbic system — structures involved with emotion. The effect was strongest in the prefrontal cortex, a brain region important for decision-making.
The researchers also identified sex differences in nicotine’s effects. Myelin-related genes increased in the prefrontal cortex of the male offspring, but decreased in the females. The opposite was observed in the hypothalamic paraventricular nucleus, a brain region involved in the regulation of stress and appetite, among other functions.
‘These findings suggest that maternal smoking may affect daughters and sons differently,’ Li said. Research was supported by the National Institute on Drug Abuse.
Society for Neuroscience. (2010, November 15). Smoking during pregnancy affects myelin genes in offspring.