Pathogens linked to Parkinson's

Paralysis in hands of a Parkinson's patientIMAGE: NATIONAL LIBRARY OF MEDICINE

Although pathogens have long been suspected to play a role in the neurodegeneration of Parkinson's and related diseases (see our December 2010 feature), very little is understood about the mechanics of the process. Specifically, scientists have been at a loss to explain what kills the dopamine-producing neurons in a region in the mid-brain that's important for movement -- resulting in motor problems such as tremors and paralysis. But last Sunday, researchers working with mice reported in Nature Neuroscience that high levels of interferon, a pro-inflammatory cytokine secreted as part of the body's normal response to infection, can selectively damage this region of the brain. The results provide strong evidence that infections or other factors that result in chronic brain inflammation, and thus high levels of interferon, "can predispose one to Parkinsonism or even cause it outright," said last...