According to new research at Western University, marijuana is the ultimate contradiction; at least when it comes to schizophrenia.
This first-of-its-kind study, published in the Journal of Neuroscience, demonstrates that a chemical found in marijuana called cannabidiol, or CBD, affects the brain in a way that makes it an ideal treatment option for schizophrenia. This research comes just months after the same lab found that adolescent exposure to THC, the other major compound found in marijuana, may lead to the onset of schizophrenia in adulthood.
“CBD is acting in a way that is the exact opposite to what THC is doing,” said Steven Laviolette, PhD, associate professor at Western University’s Schulich School of Medicine & Dentistry. “Within the same plant, you’ve got two different chemicals that are producing opposite effects in terms of psychiatric effects, molecular signaling and effects on the dopamine pathway.”
Using pre-clinical models in rodents, Laviolette and his team, led by postdoctoral fellow Justine Renard, PhD, showed that CBD can normalize schizophrenia-like disturbances in the brain’s dopamine system. By doing so, CBD alleviates schizophrenia-related symptoms linked to abnormal dopamine activity such as psychosis and cognitive problems. The researchers also demonstrated that the chemical is bypassing the molecular pathway in the brain that causes the negative side-effects typically seen in traditional antipsychotic medications.
“One of the biggest problems in treating schizophrenia is that there hasn’t been an effective new treatment on the market in a very long time,” said Laviolette. “The drugs on the market today have limited efficacy and horrible side effects; there is a desperate need for safer alternative medications.”
While CBD has shown promise as a treatment for schizophrenia in previous studies, this research is the first to show exactly how it acts on the brain to have positive results in mitigating psychiatric symptoms without causing the fatigue, lack of motivation and other side-effects associated with traditional medications.
“When we measured the molecular changes that happened in the brain, we found that the effects of CBD were bypassing traditional molecular pathways that are activated by antipsychotic drugs. We think that’s one of the reasons that it has better tolerability and fewer side-effects,” he said.
Source of text: Schulich School of Medicine & Dentistry, Western University
Original research article: Renard J, Loureiro M, Rosen LG, Zunder J, de Oliveira C, Schmid S, Rushlow WJ, Laviolette SR. Cannabidiol Counteracts Amphetamine-Induced Neuronal and Behavioral Sensitization of the Mesolimbic Dopamine Pathway through a Novel mTOR/p70S6 Kinase Signaling Pathway. J Neurosci. 2016 May 4;36(18):5160-9. doi: 10.1523/JNEUROSCI.3387-15.2016.