How Does Cannabis Work in Parkinson's Disease?
Cannabis possesses compounds such as cannabinoids that have been shown to improve the symptoms of various neurological pathologies, including Parkinson's disease.
Parkinson's disease is a neurodegenerative disorder associated with mutations in genes that affect the transmission of nerve impulses at the level of subcortical structures of the motor system, causing symptoms such as tremors at rest, difficulty walking, speaking and writing, and difficulty initiating or completing voluntary movements.
This disease is more frequent in people over 50 and its progression is slow. In addition, it affects approximately 10 million people and the male-to-female ratio is 1.5:1.
At the physiological level, there is damage to dopaminergic neurons in a structure of the basal ganglia called the substantia nigra that alters the signals between these subcortical nuclei and the cerebral cortex.
So how can cannabis work on Parkinson's? Cannabinoid receptors, especially CB1, are distributed in the central nervous system at the level of the frontal cortex, cerebellum, hypothalamus, and basal ganglia. Molecular studies demonstrated that this receptor can mediate the regulation of dopaminergic neurons and their signaling, and has effects on noradrenergic neurons that modulate these structures; as a result, it improves transmission between the structures involved in the disease.
Parkinson's patients using medical cannabis reported improvements in signs such as tremors, akinesias (inability to initiate movement), muscle spasms, and muscle rigidity.
In addition, there are non-motor symptoms related to this disease including fatigue, insomnia, depression, and pain. In these cases, CBD has been primarily useful in improving the quality of life of these patients, relieving both motor and non-motor signs.
It is because of these properties, and other effects under investigation, that cannabis represents a potential therapeutic agent in Parkinson's disease, especially to improve the quality of life of these patients and to diminish the affectation caused by this pathology.
Sources:
Cannabis and Neuropsychiatric Disorders: An Updated Review [pubmed.ncbi.nlm.nih.gov/31867704/]
Cannabis in Parkinson's Disease: The Patients' View [pubmed.ncbi.nlm.nih.gov/33216043/]
