CBD or cannabidiol is one of the most prominent compounds found in cannabis plant that belong to the class of cannabinoids. Although the use of cannabis even for medical purposes is still a complicated and politically charged issue, CBD is now a hot topic among scientists and physicians. The secret behind the booming popularity of this chemical is that CBD stands out from other cannabinoids due to its therapeutic potential as well as low toxicity and low rate of reported side effects.
Unlike THC (tetrahydrocannabinol), the most prevalent and well-known compound of cannabis, CBD is a non-psychoactive chemical which doesn’t produce any mind-altering effect and doesn’t make people feel “stoned”. In fact, it offers a large number of health benefits becoming a valuable therapeutic agent for the treatment of certain health conditions.
The difference between CBD and other cannabinoids comes down to the way CBD interacts with the Endocannabinoid System (ECS), a network of cannabinoid receptors in the brain and throughout the nervous system. The receptors in ECS are responsible for different functions including coordination, emotion, memory, cognition, immune and endocrine systems, etc. The two main cannabinoid receptors in the brain are CB1 and CB2 discovered in 1990 and 1993, respectively. CB1 receptors are found mainly in the central nervous system as well as in liver, kidneys and lungs in a smaller amount, while CB2 is part of the immune system. These receptors are not only sensitive to neurotransmitters produced naturally inside the brain, like serotonin or dopamine, but also external chemicals, in this case cannabinoids.
- CB1 and CB2 receptors
Research has shown that CBD has no binding affinity for certain cannabinoid receptors. Unlike its psychoactive sibling THC which stimulates these receptors affecting behavior, reaction, coordination, emotion, short-term memory and other functions, CBD doesn’t directly interact with the CB1 and CB2 receptors, which partly explains why CBD is not psychoactive. Even more interesting, CBD activates a number of non-cannabinoid receptors in the brain reducing the negative effects of THC and producing a number of health benefits.
Researchers categorize CBD as an antagonist of CB1 agonists, including THC. It counteracts the psychoactive effect of THC by suppressing its ability to stimulate cannabinoid receptors in the brain. While THC directly activates the cannabinoid receptors causing a high or euphoria, CBD modulates its influence on the cognitive function and effectively mutes its psychoactive effect. That’s why scientists often call THC the “bad cannabinoid” and CBD “the good cannabinoid”.
- The Serotonin receptor and depression alleviation
A joint research in animal models conducted by the University of Sao Paolo and King’s College in London has shown that CBD is able to stimulate the 5-HT1A serotonin receptor producing antidepressant effect. 5-HT1A receptor is involved in a number of processes including anxiety, pain perception, sleep, appetite, etc. CBD acts similar to pharmaceutical antidepressants reducing serotonin absorption into the brain cells and hence leaving more active serotonin floating in the spaces between the neurons. In this way CBD can help reduce stress, anxiety and other symptoms of depression including sleep and appetite disorders. The major advantage of CBD is that it’s a natural, non-toxic antidepressant without any serious side-effects reported up till now.
- The “vanilloid receptor” and pain modulation
CBD directly interacts with several ion channels, including the TPVR1 receptor. The function of TPVR1 is the regulation of body temperature as well as the sensation of heat and pain. It also mediates the curative effect of medicinal herbs. In fact, scientists refer to the TPVR1 as the “vanilloid receptor”, as vanilla bean is historically known as a folk cure for headache. Being an agonist of TPRV1, CBD is also an effective means to modulate body temperature, pain and inflammation. A 2012 research has shown that targeting TPVR1 along with α3 glycine receptors, CBD significantly suppresses inflammatory and neuropathic pain without generating analgesic tolerance in animal models. Researchers suggest that CBD has the potential to become a valuable therapeutic agent for the treatment of chronic pain.
- The “orphan receptor” and cancer cell proliferation
Finally, CBD is known for the ability to block the GPR55 which has been nicknamed as an “orphan receptor” since scientists are not yet sure which larger group of receptors it belongs to. Among other physiological processes, GPR55 is responsible for blood pressure modulation and bone density. When activated, GPR55 generates cancer cell proliferation and speeds up the process of bone reabsorption. With the potential to block GPR55 signaling, CBD reduces both the risk of cancer and inhibition of metastasis.
Although a lot of research still need to be done to discover the complete therapeutic value of CBD, there’s enough scientific evidence to prove that CBD has the potential to become a valuable therapeutic agent in the treatment of a number of health conditions.