Photobiomodulation for Parkinson's Disease
Parkinson's disease, the second most common neurodegenerative disease after Alzheimer's [1,2], casts a long shadow on millions of lives worldwide.
Characterized by a progressive loss of dopaminergic neurons and a cascade of cellular dysfunction, Parkinson's presents a significant challenge for both patients and healthcare providers. While current treatment strategies focus on managing symptoms, the search for therapies that can slow or halt disease progression remains paramount.
This article explores the potential of photobiomodulation (PBM) as a novel approach to Parkinson's disease.
Understanding Parkinson's Disease: A Delicate Balance Lost
Parkinson's disease disrupts the delicate balance within the brain, particularly in the substantia nigra, a region responsible for dopamine production.
This vital neurotransmitter governs movement, and its decline leads to the hallmark motor symptoms – bradykinesia (slowness of movement), rigidity, resting tremor, and postural instability.
However, Parkinson's extends beyond movement issues, encompassing a spectrum of non-motor symptoms like fatigue, pain, sleep disturbances, cognitive decline, and mood disorders [1,2].
Ayaz, Z., Naz, S., Khan, N., Razzak, I., & Imran, M. (2022) [3]
The disease unfolds through a complex interplay of factors. Mitochondrial dysfunction, the powerhouse of the cell, disrupts energy production. Alpha-synuclein, a protein, accumulates abnormally, forming Lewy bodies, toxic deposits that disrupt neuronal function. Neuroinflammation, a state of chronic low-grade inflammation in the brain, further exacerbates the damage [1,2].
Current Treatment Landscape: Managing Symptoms, and Seeking Solutions
The mainstay of Parkinson's treatment is dopamine replacement therapy, often with levodopa, to replenish depleted dopamine stores. While initially effective, this approach can lead to motor fluctuations ("on" and "off" periods) and dose-related side effects like dyskinesia (involuntary movements).
Other medications target specific symptoms, but none can halt the disease progression [1,2]. According to studies, levodop improves slowness in movement, stiffness, and continuous walking over 3 months, but the response of tremors varies in different individuals and may be short-lived. Speech disorders, swallowing, and instability improve at the beginning of treatment, but the central symptoms generally do not respond to the drug. Other side effects of this drug include marked tremors [2].
Deep brain stimulation (DBS), a surgical procedure, offers some motor symptom relief in advanced stages. However, its invasive nature and potential side effects limit its application. The urgent need for disease-modifying therapies that address the underlying causes of Parkinson's disease has become increasingly clear.
Introducing Photobiomodulation for Parkinson’s Disease
Photobiomodulation (PBM) emerges as a promising, non-invasive approach with the potential to improve the lives of people with Parkinson's disease. PBM utilizes low-level laser or light-emitting diode (LED) therapy to deliver specific wavelengths of light that interact with cellular components. This approach uses light therapy to potentially improve brain function and manage Parkinson's symptoms.
The primary target of PBM in Parkinson's disease is the mitochondria. By absorbing specific wavelengths of light (red and near-infrared), PBM stimulates cytochrome-c-oxidase, a key enzyme within the mitochondrial electron transport chain. This stimulation enhances mitochondrial function, leading to increased ATP production – the cell's energy currency [2].
Early research, particularly in animal models, shows promise with PBM reducing movement problems, increasing dopamine-producing cells, and improving balance and coordination [2].
While human trials on PBM for Parkinson's disease remain limited, early findings are positive. Studies have demonstrated improvements in motor function, mobility, gait, balance, cognition, and quality of life, with a good safety profile. Further research is needed to optimize treatment parameters, identify the most responsive patient subgroups, and elucidate the underlying mechanisms of action [1,2,4].
A home-based brain photobiomodulation treatment study by Hamilton et al. (2019) on Parkinson's disease patients also showed promising results. Among participants, 55% reported improvements in symptoms like tremor, stiffness, gait, swallowing, speech, facial expressions, fine motor skills, smell, and social confidence. Notably, these improvements were sustained for up to 24 months, with assessments reported by patients themselves, their spouses, and their doctors [5].
Finally, a key finding across all the studies reviewed in Bicknell, B. et al. (2024) [1] is the observed neuroprotective effect of PBM. According to this source, photobiomodulation PBM applied to the brain has also been shown to:
- Reduced scarring: The treatment appeared to lessen the formation of scar tissue in the brain, a common feature of Parkinson's;
- Lowered cell stress: Photobiomodulation seemed to reduce the damaging effects of stress on brain cells;
- Calmed inflammation: The treatment indicated a potential ability to reduce inflammation in the brain, another factor linked to Parkinson's;.
- Reduced protein toxicity: The application of photobiomodulation may help lessen the harmful effects of a protein called alpha-synuclein, which is involved in Parkinson's disease;
- Improved blood flow: Photobiomodulation administration potentially reduced leakage from blood vessels in the brain, which is important for healthy brain function;
- Enhanced activity: Animals treated showed signs of improved movement and overall behavior.
Looking Forward: Illuminating the Future of Parkinson's Treatment
Photobiomodulation (PBM) offers a safe, non-invasive, and potentially disease-modifying approach for Parkinson's disease. Its ability to target multiple aspects of the disease process, including mitochondrial dysfunction, neuroinflammation, and alpha-synuclein clearance, holds immense promise. As research progresses, PBM has the potential to become a valuable tool in the fight against Parkinson's disease, offering not just symptom management but a chance to slow or halt disease progression and improve the quality of life for patients.
The best approach for each individual will likely depend on factors like light wavelength, intensity, and dose. As research continues, PBM could become a valuable tool in managing Parkinson's disease and improving quality of life for those affected.
References
1. Bicknell, B., Liebert, A., & Herkes, G. (2024). Parkinson's Disease and Photobiomodulation: Potential for Treatment. Journal of personalized medicine, 14(1), 112. https://doi.org/10.3390/jpm14010112
2. Ahrabi, B., Tabatabaei Mirakabad, F. S., Niknazar, S., Payvandi, A. A., Ahmady Roozbahany, N., Ahrabi, M., Torkamani, S. D., & Abbaszadeh, H. A. (2022). Photobiomodulation Therapy and Cell Therapy Improved Parkinson's Diseases by Neuro-regeneration and Tremor Inhibition. Journal of lasers in medical sciences, 13, e28. https://doi.org/10.34172/jlms.2022.28
3. Ayaz, Z., Naz, S., Khan, N., Razzak, I., & Imran, M. (2022). Automated methods for diagnosis of Parkinson's disease and predicting severity level. Neural Computing and Applications, 35, 1-36. https://doi.org/10.1007/s00521-021-06626-y
4. Liebert, A., Bicknell, B., Laakso, EL. et al. Improvements in clinical signs of Parkinson’s disease using photobiomodulation: a prospective proof-of-concept study. BMC Neurol 21, 256 (2021). https://doi.org/10.1186/s12883-021-02248-y
5. Hamilton, C. L., El Khoury, H., Hamilton, D., Nicklason, F., & Mitrofanis, J. (2019). "Buckets": Early Observations on the Use of Red and Infrared Light Helmets in Parkinson's Disease Patients. Photobiomodulation, photomedicine, and laser surgery, 37(10), 615–622. https://doi.org/10.1089/photob.2019.4663