(University of Pittsburgh Schools of the Health Sciences) Researchers at the University of Pittsburgh School of Medicine have uncovered a major reason why the Parkinson's-related protein alpha-synuclein, a major constituent of the Lewy bodies that are the pathological hallmark of Parkinson's disease (PD), is toxic to neurons in the brain. The finding has the potential to lead to new therapies that could slow or stop progression of the devastating illness. The new research appears online today in Science Translational Medicine.