By Nancy Deutsch
NEW YORK, May 17 (Reuters Health) - Scientists have discovered a form of communication in the brain previously undetected, and their finding may lead to more information about certain diseases, such as multiple sclerosis (MS).
It has long been known that the brain's nerve cells communicate with one another across synapses, a gap that is the point of contact between two cells.
But while conducting research on rats, researchers at Oregon Health Sciences University in Portland and the Medical Research Council in Oxford, UK, have discovered that synapses form between nerve cells and another type of cell found in the brain, an immature form of the oligodendrocyte.
The function of oligodendrocytes is to myelinate (wrap around) nerve fibers. This myelination allows information to pass quickly along nerve fibers, speeding communication between nerve cells. In patients with demyelinating diseases--such as multiple sclerosis--the wrapping deteriorates, so important messages are communicated slowly, if at all.
If more research can determine how nerve cells communicate with immature oligodendrocytes, it may be possible to spur the cells to step up and form myelin sheaths that have been destroyed, according to the report in the May 11th issue of Nature.
Before birth, the human brain produces oligodendrocyte precursor cells (OPCs), study co-author Dr. Craig E. Jahr, a senior scientist at the Oregon Health Sciences University, told Reuters Health. Some of these OPCs mature into oligodendrocytes, but other OPCs remain in this seemingly immature state, even in adult brains.
The function of OPCs in adults is unknown, but they could serve as a reservoir for mature oligodendrocytes, Jahr explained.
If researchers can figure out a way to block the synaptic connection to OPCs, the cells may go on to develop into mature oligodendrocytes--and potentially rewrap previously demyelinated nerve fibers, he said. This could restore rapid communication in patients who have had their brain-to-body communication slowed.
"This is very speculative," he cautioned, "but a better understanding of the functions of OPCs could lead, some day, to treatments of demyelinating diseases such as multiple sclerosis."
The newly discovered synapses on OPCs may not function in this way at all, he noted. It is possible that they could cause the OPCs to release other chemicals that could change the activity surrounding nerve and other brain cells, Jahr stated.
"We would be overjoyed if our results led to effective treatments for diseases like MS," he said, but he added that his team's basic research was not directed towards clinical treatments, and that any therapies based on their results will likely not be available for years.
SOURCE: Nature 2000;405:187-191.