Parkinson's and Exercise

We had a pretty lively discussion yesterday afternoon about Alzheimer’s disease and cardiovascular fitness. Interestingly, Parkinson’s disease is greatly affected by the level of exercise of the individual patient. This was a fact that first came to me while watching the PBS program Frontline in February of 2009. They had a report entitled: “My Father, My Brother, and Me,” in which a journalist documents his attempts to understand Parkinson’s. His father and brother had both been diagnosed, and he had recently found out that he was next. The entire program is available for online viewing on PBS.org, as is a transcript.

About this same time, I had heard that my father-in-law had been diagnosed with the early-onset version of the disease. I told him and my mother-in-law about the program but I doubt they ever watched it since he still rarely exercises. The central theme of the program is that Parkinson’s is a slow-moving, unstoppable force. What I found interesting is the fact that it was uniquely susceptible to a patient-oriented, no-cost intervention – exercise. The researchers interviewed in the program had been working specifically on how exercise affects Parkinson’s outcomes. It seems to slow the progression of the disease to a significant degree in most patients. They believed that dopamine-producing neurons rely on certain growth factors for their continued health after early development. Exercise either elicits or enhances these factors which may provide a protective effect when these neurons receive some type of insult later on (Glial cell-derived neurotropic growth factors.)

To demonstrate, they had two sets of monkeys. One was a control group that remained sedentary; the other was a group that was routinely exercised on a treadmill for three months. Both groups were subjected to an MPTP insult (Remember that drug that we were discussing that caused “instant” Parkinson’s?) The control group developed gross motor symptoms while the exercised group developed almost none. Although not mentioned as prominently in this program, another benefit is probably achieved by the increased direct release of dopamine and pre-dopamine molecules in response to strenuous exercise which can, to a degree, replace or supplement the missing neurotransmitter.

This has, obviously, become a point of interest for Parkinson’s researchers. If one goes to PubMed and searches for “Parkinson’s” and “Exercise,” the search will return no less than 70 papers on the subject from this year alone. Of course, this is not a panacea; indeed, nearly all patients will eventually overcome the beneficial effects of exercise and progress to later stages of the disease. Despite this, it might put a little power to control one’s own destiny back in the hands of the patient.