November 18, 2008

Steroids can cause infant brain cell death

Some drugs used in premature babies and in pregnant women at risk for preterm deliveries can kill infant brain cells, research by U.S. scientists shows.

The study indicated the class of steroid drugs, glucocorticoids, often used to help underdeveloped lungs in premature infants, irreversibly damaged baby mice's brain cells in the cerebellum, the area responsible for coordination and balance, USA Today reported.

In the study, brain cells in mice died after treatments administered four to 10 days after birth, said study author Kevin Noguchi, a post-doctoral fellow at Washington University School of Medicine. In human babies, the period would be from about 20 weeks in the womb to six weeks after birth, he said.

Noguchi said other studies indicate a synthetic steroid -- dexamethasone -- causes motor and cognitive problems in children.

The authors said the toxic effects don't seem to affect the brains of older babies, children and adults, USA Today reported.

Our studies in mice suggest that once a human infant is a few months old, these drugs -- which are used for other medical conditions, too -- don't appear to have this type of toxic effect, co-author Nuri Farber said.