Medical cannabis is the subject of much debate. There is still much we don’t know about cannabis, but researchers in the Department of Neuroscience of the Faculty of Health and Medical Sciences have made a new discovery that could prove critical to future medical cannabis research and treatment.
Cannabinoids are compounds found in cannabis and in the central nervous system. Using a mouse model, the researchers showed that a specific synthetic cannabinoid (cannabinoid WIN55,212-2) reduced essential tremor by activating the supporting cells of the spinal cord and brain known as astrocytes. Previous research on medical cannabis has focused on the nerve cells called neurons.
‘We focused on the essential tremors of the disease. It causes involuntary shaking, which can be extremely debilitating and seriously affect the patient’s quality of life. However, the cannabinoid could also have a positive effect on sclerosis and spinal cord injuries, which also lead to involuntary shaking, ”says Associate Professor Jean-François Perrier from the Institute of Neuroscience, who led the research project.
“We found that an injection of the cannabinoid WIN55,212-2 into the spinal cord turns on the astrocytes in the spinal cord, causing them to release the substance adenosine, which then reduces nerve activity and thus unwanted shaking.”
Targeted treatment with no problematic side effects
The fact that astrocytes are part of the explanation for the effects of cannabis is a completely new approach to understanding the medicinal effects of cannabis and can help improve the management of patients with involuntary shaking.
The spinal cord is responsible for most of our movements. Both voluntary and spontaneous movements are triggered when the motor neurons of the spinal cord are activated. The motor neurons connect the spinal cord to the muscles, and every time a motor neuron sends impulses to the muscles, it causes contraction, and therefore movement. Involuntary shaking occurs when the motor neurons are sending conflicting signals at the same time. And that’s why the researchers focused on the spinal cord.
“One could envision a new approach to shaking medical cannabis where – during the development of cannabis-based medicines – you target treatment to either the spinal cord or the astrocytes – or at best the astrocytes of the spinal cord.” says postdoc Eva Carlsen, who performed most of the tests during her doctoral and postdoc projects.
“This approach avoids affecting the neurons in the brain that are responsible for our memory and cognitive abilities, and we could offer effective treatment to patients suffering from involuntary shaking without experiencing one of the most problematic medical side effects Exposing cannabis. “
The next step is to conduct clinical tests on patients suffering from essential tremor to see if the new approach has the same effects on humans.
University of Copenhagen – Faculty of Health and Medical Sciences
Carlsen, EMM, et al. (2021) Spinal astroglial cannabinoid receptors control pathological tremor. Natural neurosciences. doi.org/10.1038/s41593-021-00818-4.