Clinical trial NCT03104725: Does N-Acetylcysteine Decrease Spontaneous Oxidation of Central Neural Dopamine in Parkinson's Disease?
Official title: Does N-Acetylcysteine Decrease Spontaneous Oxidation of Central Neural Dopamine in Parkinson's Disease?
Study type: INTERVENTIONAL
Overall status: TERMINATED
Phase: PHASE1
Conditions: Parkinson Disease
Cerebrospinal Fluid
Keywords: 5-S-Cysteinyldopamine
Cerebrospinal Fluid
PARKINSONS DISEASE
MONOAMINE OXIDASE INHIBITOR
Lead sponsor: National Institutes of Health Clinical Center (CC)
Sponsor class: NIH
First posted: 2017-04-07
Enrollment: 6
Sex: ALL
Minimum age (years): 18
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: yes
Allocation: NON_RANDOMIZED
Intervention model: PARALLEL
Primary purpose: BASIC_SCIENCE

Brief 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.

Detailed description: 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.

Eligibility criteria: * 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

Primary outcomes:
measure: The Mean Percent Change in Cerebrospinal Fluid (CSF) Concentration of 5-S-cysteinyl-dopamine (Cys-DA) Pre and Post-N-acetylcysteine (NAC) Treatment
timeFrame: All participants underwent a baseline LP. For PD participants, the second LP occurred approximately 2 hours after the participant had taken NAC the last NAC dose. For HV participants the second LP takes place approximately 48 hours after the first LP.
Secondary outcomes:
measure: Mean Ratio of Cys-DA/DOPAC Pre and Post-treatment Lumbar Puncture With and Without N-acetylcysteine (NAC)
timeFrame: All participants underwent a baseline LP. For PD participants, the second LP occurred approximately 2 hours after the participant had taken NAC the last NAC dose. For HV participants the second LP takes place approximately 48 hours after the first LP.
measure: Mean Percent Change in Cys-DA/DOPAC Between Pre and Post-treatment Lumbar Puncture With and Without N-acetylcysteine (NAC)
timeFrame: All participants underwent a baseline LP. For PD participants, the second LP occurred approximately 2 hours after the participant had taken NAC the last NAC dose. For HV participants the second LP takes place approximately 48 hours after the first LP.
Other outcomes:
Locations:
city: Bethesda
country: United States
facility: National Institutes of Health Clinical Center
state: Maryland
Study officials:
affiliation: National Institute of Neurological Disorders and Stroke (NINDS)
name: David S Goldstein, M.D.
role: PRINCIPAL_INVESTIGATOR
References:
citation: 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.
citation: 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.
citation: 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.