Excessive brain cell growth post injury may cause seizures

New York: The excessive burst of new brain cells after a traumatic head injury, which is believed to help in recovery, may lead to epileptic seizures and long- term cognitive decline, scientists including one of India origin warn.

"There is an initial increase in birth of new neurons after a brain injury but within weeks, there is a dramatic decrease in the normal rate at which neurons are born," said Viji Santhakumar, associate professor at Rutgers University in the US.

"This depletes brain cells that under normal circumstances should be there to replace damaged cells and repair the brain's network," she added.

Researchers found that that within a month after experimental brain injury, the number of new brain cells declined dramatically, below the numbers of new neurons that would have been detected if an injury had not occurred in rats.

They were able to prevent the excessive neurogenesis which occurs within days of the injury with a drug similar to one under trial for chemotherapy treatments.

The rate of birth of new brain cells went back to normal levels and risk for seizures was also reduced.

"That is why we believe that limiting this process might be beneficial to stopping seizures after brain injury," she said.

While the regenerative capability of brain cells, in the hippocampus - the part of the brain responsible for learning and memory - slows down as part of the ageing process, the process that occurred after a head injury was related to injury and not age, researchers said.

"It is normal for the birth of new neurons to decline as we age. But what we found in our study was that after a head injury the decline seems to be more rapid," said Santhakumar.

The study was published in the journal Stem Cell Reports.