Does N-Acetylcysteine Decrease Spontaneous Oxidation of Central Neural Dopamine in Parkinson's Disease?

Summary

Background: Parkinsons disease (PD) causes slow movement, stiffness, and poor balance. Many symptoms are due to the loss of brain cells that make the brain chemical dopamine. The cells may be damaged by the breakdown of dopamine by a process called oxidation. The drug N-acetylcysteine (NAC) can act as an antioxidant. Researchers want to test if NAC can decrease the oxidation of brain dopamine in people with PD. Objective: To look at the effect of NAC on brain chemistry in people with PD. Eligibility: People ages 18 and older with PD that were diagnosed within the past 5 years. They must be taking a monoamine oxidase inhibitor. Healthy volunteer participants ages 18 and older. Design: Participants will be screened with: Medical history Physical exam Blood and urine tests Participants will be hospitalized for 4 to 8 days. On day 1, participants will have blood and urine tests. For several hours, they cannot eat or drink anything but water and their medications. Late in the morning they will have a meal. About 2 hours later they will have a spinal tap (lumbar puncture). For this, a numbing medicine is injected into the back. A needle is inserted between the bones in the back to remove a small amount of fluid. The spinal tap may use x-rays to see inside the body. After the spinal tap, they will start taking NAC by mouth. They will take NAC twice a day for 2 more days. On the next day, they will not eat until a meal in the late morning. They will take a final NAC dose. About 2 hours later they will have a second spinal tap. Healthy Volunteer (HV) participants will receive a spinal tap on day one, followed by a second spinal tap 48 hours after the first spinal tap. HV participants will not receive NAC.

Timeline

Start

2017-09-25

Primary completion

2020-02-27

Completion

2020-02-27

Publications

• Background Goldstein DS, Holmes C, Sullivan P, Jinsmaa Y, Kopin IJ, Sharabi Y. Elevated cerebrospinal fluid ratios of cysteinyl-dopamine/3,4-dihydroxyphenylacetic acid in parkinsonian synucleinopathies. Parkinsonism Relat Disord. 2016 Oct;31:79-86. doi: 10.1016/j.parkreldis.2016.07.009. Epub 2016 Jul 20.
• Background Goldstein DS, Kopin IJ, Sharabi Y. Catecholamine autotoxicity. Implications for pharmacology and therapeutics of Parkinson disease and related disorders. Pharmacol Ther. 2014 Dec;144(3):268-82. doi: 10.1016/j.pharmthera.2014.06.006. Epub 2014 Jun 16.
• Background Goldstein DS, Jinsmaa Y, Sullivan P, Holmes C, Kopin IJ, Sharabi Y. Comparison of Monoamine Oxidase Inhibitors in Decreasing Production of the Autotoxic Dopamine Metabolite 3,4-Dihydroxyphenylacetaldehyde in PC12 Cells. J Pharmacol Exp Ther. 2016 Feb;356(2):483-92. doi: 10.1124/jpet.115.230201. Epub 2015 Nov 16.

Drugs

Indications