Glutathione and related enzymes in Parkinson's Disease Dr. Joseph C. Maroon is a neurosurgeon and a professor at the University of Pittsburgh Medical Center. His research on Alzheimers and Parkinsons disease focuses on the role of oxidative stress and Amazon.com: Immunocal Glutathione Precursor Supports Natural Glutathione Production Immune & Antioxidant Support, Cellular Health Sugar Free, Lactose Free 30 Servings : Health & Household Randomized, double'blind, pilot evaluation of intravenous glutathione in Parkinson's disease