Parkinson’s disease (PD) is a neurodegenerative disorder characterised by impaired or slowed motor function known as bradykinesia. Patients with PD exhibit progressive damage to dopaminergic neurons in the substantia nigra region of the brain. Patients with PD may present with a multitude of symptoms including tremors, muscle rigidity, impaired speech, poor sleep as well as anxiety and depression.
Cannabinoids are potent antioxidants and possess neuroprotective properties with preclinical evidence suggesting they may be helpful in reducing the progression of PD. Up-regulation of the endocannabinoid system is well documented to attenuate anxiety, depression and poor sleep, all symptoms experienced by PD suffers.
This image is a simplification for website aesthetics only. For more information please refer to the clinical studies referenced below.
Possible Benefits of Endocannabinoid Activation with Cannabidiol
The endocannabinoid system has been implicated in many scientific studies as a mediator of anxiety and depression as well as sleep through its interaction with the neurotransmitter serotonin. Cannabidiol is known to mimic natural serotonin by binding to the 5HT1Areceptor, a property that has been suggested to explain the reduction in anxiety, depression and improved sleep experienced by patients. Patients with PD may experience REM sleep behavior disorder (RBD) causing irregular movement or “acting out” of dreams. In a recent study, Chagas et al. (2014) found four patients treated with CBD had prompt, substantial and persistent reduction in the frequency of RBD-related events.
Antioxidant and Neuroprotection
Dopamine is an essential neurotransmitter responsible for relaying movement signals in the brain. Patients with PD experience a degeneration of dopaminergic neurons in the motor center of the brain, which ultimately leads to a movement disorder.
Dopamine synthesis in the brain is a complicated process governed by environmental and genetic factors. Dopamine metabolites formed by irregularities in its synthesis are often toxic, reactive and create an oxidative environment. Oxidative stress has been suggested as a possible cause and has been implicated in the progression of PD.
Cannabidiol possesses potent antioxidant properties, which enable it to neutralise reactive oxidative species, a quality that in turn facilitates the protection of dopaminergic neurons. While there is promising preclinical and animal models to suggest CBD may be able to attenuate the progression of PD, human data is lacking. Cannabinoid medication is an exciting development in the treatment of many neurodegenerative disorders.
Chagas, M. H. N., Eckeli, A. L., Zuardi, A. W., Pena, Pereira, M. A., Sobreira, Neto, M. A., Sobreira, E. T., … & Crippa, J. A. S. (2014). Cannabidiol can improve complex sleep-related behaviours associated with rapid eye movement sleep behaviour disorder in Parkinson’s disease patients: a case series. Journal of clinical pharmacy and therapeutics, 39(5), 564-566.
Chagas, M. H. N., Zuardi, A. W., Tumas, V., Pena-Pereira, M. A., Sobreira, E. T., Bergamaschi, M. M., … & Crippa, J. A. S. (2014). Effects of cannabidiol in the treatment of patients with Parkinson’s disease: An exploratory double-blind trial. Journal of Psychopharmacology, 28(11), 1088-1098.
Fernandez-Ruiz, J., Sagredo, O., Pazos, M. R., Garcia, C., Pertwee, R., Mechoulam, R., & Martinez-Orgado, J. (2013). Cannabidiol for neurodegenerative disorders: important new clinical applications for this phytocannabinoid. British journal of clinical pharmacology, 75(2), 323-333.
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Kluger, B., Triolo, P., Jones, W., & Jankovic, J. (2015). The therapeutic potential of cannabinoids for movement disorders. Movement Disorders, 30(3), 313-327.