(Ivanhoe Newswire) -- A place some refer to as "second brain" of the body
may not lie where you expect it to. Most of us who associate serotonin with
brain neurology are surprised to learn more than 95 percent of the body's
serotonin occurs in the gastrointestinal tract, which has a complex neuronal
circuit, much like the brain.
Now a Mayo Clinic research team has identified a number of genetic variants in
serotonin genes that they believe are key players in irritable bowel syndrome
(IBS).
IBS is one of the most common chronic disorders of the digestive tract. It can
cause years of discomfort or pain, limit a person personally and professionally,
and cost millions nationally in medical costs and lost time.
"It's been known that some drugs that alter serotonin levels in the body also
have an effect on motility, thus prompting IBS-like symptoms, but the genetic
and molecular mechanism for IBS was unclear," study presenter Yuri Saito, M.D.,
a Mayo Clinic gastroenterologist, was quoted as saying.
Using a familiar analogy, Dr. Saito explained, "Rather than sending out a few
patrol cars to look for culprits by rounding up 'the usual suspects,' we
launched a genetic dragnet that took an objective, unbiased look at a broader
range of possibilities."
The researchers found a number of previously unknown IBS associations. They
concluded that many more serotonin-related genes were implicated in IBS than
first thought. The implicated genes relate to serotonin synthesis, metabolism
and receptors. The researchers also found IBS may be caused by multiple genes,
and there may be distinct as well as overlapping molecular mechanisms that cause
the diarrhea and constipation that are the two major symptoms of IBS.
The findings offer future researchers specific targets for drug development or
other therapies to combat IBS.
SOURCE: Presented at Digestive Disease Week, New Orleans, May 4, 2010
