LOS ANGELES, March 26 (Xinhua) -- Brain stem cells in the human body with the most severe form of multiple sclerosis (MS) look much older than they actually are, according to a study led by researchers of the University of Connecticut.

The prematurely old cells act differently in the brain than normal ones, and could be the key to new treatments for the disease, according to the study published in the Proceedings of the National Academy of Sciences.

Stephen Crocker, a health neuroscientist at the University of Connecticut, and his colleagues found that brain stem cells from primary progressive MS patients look decades older than otherwise similar cells from healthy people of the same age.

MS disrupts the nerves' ability to transmit signals around the body. For example, MS can make it hard to walk or hold a pen.

The problem is caused by inflamed and degenerating insulation around the nerves, called myelin. Nerves with damaged myelin can short out or pick up stray signals, according to the study.

Most people with MS have long periods of remission, when they recover and can walk and live as they did before developing the disease, but MS is a progressive disease.

Currently, there is only one drug for the disease, and it slows the progression but does not halt it, said the study.

Not only do the brain stem cells from primary progressive MS patients look older, they also act older, the team found.

"Primary progressive MS is a devastating disease for which we are still missing effective treatments, and regenerating myelin is a major need that current therapeutics have not met," said Valentina Fossati of the New York Stem Cell Foundation.

"We are excited that the study of human stem cells in a dish led to the discovery of a new disease mechanism that could be targeted in much-needed therapeutics for progressive MS patients," Fossati said.

Anna Williams, a neurologist at the University of Edinburgh, said understanding the differences between brain stem cells from people with MS and those from healthy people will hold vital clues to developing much-needed treatments.