Canada has recently passed new legislation legalizing cannabis throughout the country. Lineups at government-regulated stores were seen all over the country, with people eagerly awaiting legally sold marijuana for the first time ever in Canada. The demand is high, with many shops around Canada quickly selling out of many popular products on day 1. As the market is set to explode, the Canadian government has begun to invest heavily in cannabis research, with the Canadian Institutes of Health Research funding around $20 million worth of projects within the last 5 years and ready to dole out another $3 million to cannabis research in the next few months.
Currently, the Canadian government has set tight restrictions and regulations on the sale of cannabis. There is an age limit, a carrying limit of 30 grams per person, and restrictions on promoting the use of cannabis, particularly to those under 18 years of age. To sell cannabis, you must be licensed by the government; however, there are currently 129 producers allowed to distribute the plant, making it highly accessible. You can buy from in-person or online stores, where cannabis products are classified into two strains: indica, which gives a typically calming high, and sativa, which has more invigorating effects. Each strain can be purchased individually, as a hybrid, or as a blend in either flower, ground, pre-rolled, oil, spray, or pill form.
The cannabis plant is renowned for its trichomes, small structures on the epidermis of the cannabis plant that release compounds with strong odors that deter animals from eating them. The two chemicals that cannabis primarily secretes are tetrahydrocannabinol (THC), which is responsible for its mind-altering effects, and cannabidiol (CBD), which has anti-inflammatory and anti-anxiety properties. These compounds exert their effects by binding to endogenous cannabinoid G protein-coupled receptors (GPCRs) and activating downstream mitogen-activated protein kinase (MAPK) signaling. The two most characterized receptors are cannabinoid receptor type 1 (CB1) and cannabinoid receptor type 2 (CB2), which are distributed throughout the body, including in the brain, peripheral nervous system, gut, immune system (in macrophages, lymphatic tissues, and the spleen), arteries, heart, lungs, and endocrine glands. Because of this, ingestion of cannabis can have widespread physiological effects, ranging from increased appetite to cytokine release and dampening of pain.1,2
While the main attraction of legalizing cannabis lies in its recreational use, marijuana plants have also been studied extensively for both their therapeutic potential, giving rise to a global medical marijuana industry. Though cannabis itself is still not approved by the FDA for any specific use, CBD was approved this year for patients who suffer from two rare forms of epilepsy, Lennox-Gastaut syndrome and Dravet syndrome, that can cause frequent and severe seizures. Two other synthetic cannabinols, dronabinol and nabilone, were approved many years ago for the treatment of nausea and vomiting related to chemotherapy in patients with cancer (dronabinol is also approved to treat anorexia in patients with HIV). With cannabinoid receptors found in the digestive system (one of the reasons people get the munchies after smoking cannabis), much current research has gone into monitoring the effects of cannabinols on gut-associated diseases, like Crohn’s disease, irritable bowel syndrome, and gastric ulcers. These compounds have also been studied as therapeutics for chronic pain and inflammation, ocular pathologies (e.g. glaucoma, retinitis pigmentosa, and diabetic retinopathy), and neurodegenerative diseases.1
Unfortunately for scientists, the Canadian government has yet to rescind its regulations on using cannabis for research purposes. An exemption must still be requested prior to performing any study on the plant, though several prominent researchers are asking the government to ease the current restrictions, with the hopes that more data can be gleaned from cannabis’ legalization that would address both the risks and potential benefits of the plant and the compounds it produces.
- Maurya N, Velmurugan BK. Therapeutic applications of cannabinoids. Chem Biol Interact. 2018;293:77-88.
- Vadivelu N, Kai AM, Kodumudi G, Sramcik J, Kaye AD. Medical Marijuana: Current Concepts, Pharmacological Actions of Cannabinoid Receptor Mediated Activation, and Societal Implications. Curr Pain Headache Rep. 2018;22(3):1-10.