Parkinson's Disease

In Parkinson's disease (PD), the protein α-synuclein misfolds and then assembles into fibrils. These fibrils coalesce to form Lewy bodies inside of neurons. As Lewy bodies accumulate in dopamine neurons, patients have increasing difficulty with movements. To counter these symptoms, PD patients receive L-dopa to enhance the function of their dopamine neurons. Eventually, so many α-synuclein prions accumulate that PD patients become refractory to L-dopa therapy.