Objective: This study is to test whether N-acetylcysteine (NAC) inhibits the spontaneous oxidation of central neural dopamine as indicated by the cerebrospinal fluid (CSF) concentration of 5-S-cysteinyl-dopamine (Cys-DA) in patients with Parkinsons disease (PD). Study population: The study population comprises up to 35 participants with early (less than or equal to 5 years from diagnosis), mild, levodopa-untreated PD and up to 6 healthy volunteer participants. The PD participants will be on an inhibitor of monoamine oxidase (MAO) that is prescribed for their disease. Design: The study has a two groups employing a pretest-posttest design. Each participant undergoes a lumbar puncture (LP) as an inpatient at the NIH Clinical Center to obtain cerebrospinal fluid (CSF) for assays of Cys-DA, 3,4-dihydroxyphenylacetic acid (DOPAC), and related biochemicals. For PD participants, the second LP is done after the participant has taken at least 5 doses of NAC (2 grams orally twice per day). The LP takes place about 2 hours after the last NAC dose. For HV participants the second LP takes place approximately 48 hours after the first LP. Outcome measures: The main outcome measure is the CSF concentration of Cys-DA. Other outcome measures are levels of other catecholamine-related neurochemicals or of indices of oxidative stress. Depending on the results, an exploratory study may be done involving NAC at 1 gram orally twice per day.
- INCLUSION CRITERIA: - PD diagnosed within the past 5 years - Taking a monoamine oxidase (MAO) inhibitor - Able to provide consent - At least18 years old EXCLUSION CRITERIA: - Taking levodopa in any form - Known allergy to NAC - Already taking an anti-oxidant dietary supplement (e.g., Olive Leaf Extract, MitoQ) - A condition that would increase risk from a lumbar puncture (e.g., symptomatic spinal stenosis or myoclonus) - History of a post-spinal headache that required treatment with a blood patch - On a prescribed anti-coagulant (e.g., Coumadin, Plavix) - Pregnant or breast-feeding - History of alcohol or drug abuse - Any medical condition thatcould put subjects at increased risk. Potential participants are excluded who have evidence of bone marrow, liver, or kidney failure based on abnormal screening lab results. - On a medication that could interfere with the scientific results. An example of an exclusionary drug is the catechol-O-methyltransferase inhibitor entacapone. Tricyclic anti-depressants are another type of exclusionary drug