N-Acetyl Cysteine Improves Symptoms of Parkinson’s Disease

by | Nov 3, 2020 | 2019, Amino Acids, Brain Health, NAC (N-Acetyl Cysteine), Parkinson's

Written Chrystal Moulton, Staff Writer. Three months administration of N-acetyl-cysteine (NAC) in participants with Parkinson’s disease significantly increased dopamine binding as well as motor and non-motor symptoms of Parkinson’s disease.

elderly man gripping ballParkinson’s disease is a chronic disease affecting more than 1 million Americans and with no existing interventions that can slow the progression of the disease. Parkinson’s disease is characterized by the gradual degeneration of dopaminergic neurons in the brain 1. Research suggests that damage by reactive oxygen species (ROS) could play a significant role in the progression of Parkinson’s disease 2,3. NAC has been clinically shown to reduce oxidative stress and increase glutathione levels in the brain 4.

In an open label trial 5, 42 individuals (40-80 years old) clinically diagnosed with Parkinson’s disease were randomly assigned to either NAC or control in a 2: 1 randomization technique (n=28 NAC, n=14 control). Study duration was 3 months. At the beginning and end of the trial period, participants received DaTscan SPECT imaging and assessment of Parkinson’s symptoms was conducted using UPDRS (Unified Parkinson’s Disease Rating Scale). The NAC group took 1200mg NAC daily (600mg capsule twice a day with meals) and had intravenous infusions (50mg NAC/kg body weight) once a week. On days when IV infusions were scheduled, participants did not take NAC capsules. Participants maintained prescribed regimens during the course of the study. Individuals assigned to the NAC intervention were given NAC in addition to existing treatment regimen. The purpose of the study was to assess the effects of NAC supplementation on Parkinson’s disease symptoms and DAT (dopamine transporter) binding (observed in the caudate and putamen).

Changes in DAT binding results from baseline to end of 3months showed significant improvement in the NAC group (caudate: 0.092, p = 0.023; putamen: 0.135, p = 0.001). No significant difference observed in the control. Mean difference in DAT binding from baseline to end of trial between NAC and control were statistically significant (NAC vs Control- caudate: 0.151, p = 0.030; putamen: 0.245, p = 0.001). UPDRS scores from baseline to the end of trial were significantly improved in the NAC group (Total mean difference pre to post: -4.29, p < 0.001). Significant decrease in UPDRS scores were observed for motor symptoms (-2.88, p = 0.003) and non-motor symptoms (-1.41, p = 0.010). A positive trend in total UPDRS score among participants of the control group was observed, however, this trend was not significant (2.36, p = 0.071). The difference in UPDRS results between NAC and control was significant (6.64, p < 0.001). Researchers found that age and gender were significant predictors of serotonin uptake. Women had higher UPDRS scores compared to their male counterparts (8.67, p = 0.009) and an average increase of 0.44 in total UPDRS score was observed for each year of age (p = 0.025). Serotonin binding was significantly improved in the NAC group (0.14, p = 0.001) and significantly decreased in the control group (-0.11, p = 0.037). Age was a significant predictor of serotonin binding with an average decrease of 0.009 per each year of age (p = 0.005).

Overall, administration of NAC (IV and oral combined) significantly improved symptoms of Parkinson’s disease and dopamine transporter binding in patients with Parkinson’s. The study suggests that NAC in addition to current therapies could help manage and further improve symptoms of Parkinson’s disease. Additional studies will be needed to explore effective treatment modalities and dosage for NAC in the management of Parkinson’s symptoms.

Source: Source: Monti, Daniel A., George Zabrecky, Daniel Kremens, Tsao‐Wei Liang, Nancy A. Wintering, Anthony J. Bazzan, Li Zhong et al. “N‐Acetyl Cysteine Is Associated With Dopaminergic Improvement in Parkinson’s Disease.” Clinical Pharmacology & Therapeutics 106, no. 4 (2019): 884-890.

© 2019 The Authors Clinical Pharmacology & Therapeutics © 2019 American Society for Clinical Pharmacology and Therapeutics

Posted November 2, 2020.

Chrystal Moulton BA, PMP, is a 2008 graduate of the University of Illinois at Chicago. She graduated with a bachelor’s in psychology with a focus on premedical studies and is a licensed project manager. She currently resides in Indianapolis, IN.

Reference

  1. Pfeiffer RF, Wszolek, Z. K., Ebadi, M. Parkinson’s Disease. pp. 62-79. CRC Press; 2012.
  2. Sies H, Cadenas E. Oxidative stress: damage to intact cells and organs. Philosophical transactions of the Royal Society of London Series B, Biological sciences. 1985;311(1152):617-631.
  3. Chinta SJ, Andersen JK. Redox imbalance in Parkinson’s disease. Biochimica et biophysica acta. 2008;1780(11):1362-1367.
  4. Holmay MJ, Terpstra M, Coles LD, et al. N-Acetylcysteine boosts brain and blood glutathione in Gaucher and Parkinson diseases. Clin Neuropharmacol. 2013;36(4):103-106.
  5. Monti DA, Zabrecky G, Kremens D, et al. N-Acetyl Cysteine Is Associated With Dopaminergic Improvement in Parkinson’s Disease. Clinical pharmacology and therapeutics. 2019;106(4):884-890.