Chemical trigger of Parkinson's discovered

Last Updated: 2007-11-15 13:52:38 -0400 (Reuters Health)

NEW YORK (Reuters Health) - A team of scientists may have figured out how Parkinson's disease is triggered, a discovery that could lead to better treatments for the disease, which is marked by debilitating and uncontrollable tremors and twitches.

Parkinson's disease occurs when a protein in the brain, called alpha-synuclein, or AS, clumps together. This causes brain cells that produce dopamine to die or stop working properly, which in turn triggers the symptoms of Parkinson's disease.

What causes AS to clump together was a mystery, until now.

Dr. William J. Burke from the Saint Louis VA Medical Center and Saint Louis University Health Sciences Center, Missouri and associates have found in rats that dopamine itself plays a role in destroying the neurons that produce it. The mediating factor, it seems is a chemical by-product of dopamine known as 3,4-dihydroxyphenylacetaldehyde, or DOPAL.

In cell cultures, DOPAL causes AS to clump together, the researchers found, while in rats they observed that injection of DOPAL causes dopamine neurons to die and AS clumps to form.

"Taken together, our results are consistent with the view that DOPAL may account for the selective loss of dopamine neurons" mediated by toxic AS clumps, the scientists report.

Burke added in a statement from Saint Louis University: "For the first time, we've identified the chemical that triggers the events in the brain that cause this disorder. We believe these findings can be used to develop therapies that can actually stop or slow this process."

SOURCE: Acta Neuropathologica, October 27, 2007.