Another step on the way to curing Parkinson’s disease has been taken by an ISU researcher, and the results of his research could have a major impact on the way pesticides are handled in the Midwest.

Anumantha Kanthasamy, associate professor of biomedical sciences, has been researching Parkinson’s disease for 10 years and recently published work linking pesticide exposure to the development of Parkinson’s. Kanthasamy was triggered to work on a cure for the disease after his grandfather was diagnosed with it.

Kanthasamy came upon the link between pesticides and Parkinson’s in recent epidemiological studies and decided to study the process by which the pesticides kill basal ganglia – cells that produce dopamine in the brain, a lack of which causes Parkinson’s.

“Once we know how [the chemicals] kill the cells, then we can intervene in that process,” he said.

To research the effects of pesticides on basal ganglia cells, the cells – taken from rodents – are cultured in a petri dish and small concentrations of a toxin are added, he said.

“If they kill the cells, we look for what genes are involved in the process,” he said.

“Up until now . people believed that mental and genetic factors were responsible” for the cause of Parkinson’s, he said.

Robert Rodnitzky, professor of neurology at the University of Iowa, is also working on the relationship between Parkinson’s and pesticide exposure.

“There’s a relationship between rural living and Parkinson’s and also a relationship between well water and Parkinson’s,” he said.

Rodnitzky has been looking into epidemiological surveys and finding out what the exposures of Parkinson’s patients have been, he said.

“Rotenone has been studied the best . another called periquat has a close relationship to Parkinson’s. But as far as we know, any of the pesticides could do it,” he said.

Pesticide exposure, however, is not the only possible cause.

“[A person with] the right genetic makeup and right experiences in life will have a greater chance of having Parkinson’s,” he said.

“We’re evaluating sibling pairs that have Parkinson’s disease, and then we survey their genetic makeup to see what genes are responsible for susceptibility to environmental toxins.”

Research into causes for Parkinson’s is making progress, Kanthasamy said, but it’s hard to say how close a cure is.

“The research, in my opinion, is going in the right direction,” he said.

Fast Facts

Parkinson’s disease

Affects between 1 million and 1.5 million Americans

Appears at any age, but risk increases with age

Primary symptoms include: stiffness in the muscles; tremors that sometimes involve the head, neck, face and jaw; bradykinesiam, or slowness of movement; poor balance; difficulty walking, including decreased or nonexistent arm swing with very short, shuffling steps.

Other symptoms include: depression, sleep disturbances, dizziness, stooped posture, constipation, dementia, and problems with speech, breathing, swallowing and sexual functions.

The cause of Parkinson’s disease is not known. Although a defective gene was recently found in a few families with extraordinarily high incidences of the disease, most researchers believe that in the vast majority of cases, genetic factors alone are not responsible for causing the disease. Instead, it is suspected that Parkinson’s usually results from the combination of a genetic predisposition and an as yet unidentified environmental trigger.

Treatments highly involve the patients. Regular exercise and/or physical therapy are essential for maintaining and improving mobility, flexibility, balance and a range of motion and for warding off many of the secondary symptoms. Exercise is as important as medication.The disease seems to advance more slowly in people who remain involved in their pre-Parkinson’s activities or who find new activities to amuse them and engage their interest.

– Source: Parkinson’s Disease Foundation Web site, www.pdf.org