Jenny Wilkerson, University of Florida and Lance McMahon, University of Florida
Cannabidiol or CBD has become a household name. On many social media sites people suggest, "But have you tried CBD oil?" In posts that relate to health-related issues.
CBD, a minor component of marijuana, is widely referred to as a miracle of nature by CBD enthusiasts. Unlike the major constituent of delta-9-tetrahydrocannabinol (THC), it is not high. However, given the recent increase in its popularity, you would think that the molecule is magical.
We are scientists of Behavioral Pharmacology and investigate how drugs affect the body. In particular, we have an interest in the development of new drugs for the treatment of pain with reduced drug abuse potential and therapeutic interventions for drug abuse. Although there is a scientific interest in using CBD for pain and drug addiction as well as many other medical indications, there is much that we do not yet know about CBD.
CBD and THC: How do they work?
Medications affect the body by binding to and acting on different protein molecules, usually on the surface of the body cells called receptors. These receptors then send out signals that can affect body functions.
Marijuana has an effect on the body because many animals have receptors called "cannabinoid receptors". There are two known cannabinoid receptors responsible for the effects of marijuana. Only one of them, the cannabinoid type 1
CBD does not bring people to the highest level because CBD does not bind or participate in CB1R. CBD also does not bind to the other cannabinoid receptor, the cannabinoid type 2 receptor (CB2R), which occurs mainly on immune cells. In contrast, THC binds and activates these two receptors.
Studies suggest that CBD affects several other receptor types. These include the serotonin 5-HT1A receptor, which helps to regulate sleep, mood, anxiety and pain. CBD can also indirectly alter the body's own cannabinoid receptor activity.
However, scientists do not yet know exactly how CBD affects the body. Similarly, many health-related anecdotes that relate to CBD are not based on sound scientific evidence and may be based on well-documented placebo effects. However, there is strong evidence that CBD has sustained health benefits stubborn epilepsy.
It's been nearly six years since the history of the Charlotte web strain marijuana has invaded national and international media. This marijuana variety was named after Charlotte Figi, who fought with persistent pediatric epilepsy until she received oil of the type containing a higher CBD to THC level.
Charlotte's father saw an online video of a California child with seizures that were successfully treated with marijuana. As it turned out, the drug that helped Charlotte was not THC, but CBD.
Based on clinical evidence, GW Pharmaceuticals developed and licensed its own CBD extract, a drug now called Epidiolex. Clinical trials of Epidiolex for the indication of Dravet syndrome and Lennox-Gastaut syndrome, two forms of pediatric epilepsy, have been consistently positive.
In June 2018, the Food and Drug Administration Epidiolex approved for the treatment of these two forms of childhood epilepsy on other treatments not addressed.
While clinical trials of epidiolex were ongoing, a seminal Indiana University study showed a possible mechanism for CBDs to have amazing effects on Dravet and Lennox-Gastaut syndromes. These two syndromes are associated with genetic mutations in two genes that are important for the regulation of sodium ions.
A Special Understanding
Nerve cells regulate the way they send signals, through ions or molecules with either a total positive or negative electrical charge, into and out of their cells. The most common ions that regulate nerve cell signals are sodium, potassium, calcium and chloride. These ions move into and out of the cell through pores called ion channels.
However, in many forms of epilepsy, the movement of ions is not properly controlled. This leads to deviant firing of the nerve cells of the brain and seizure activity.
In both forms of epilepsy, for which CBD is effective, there are changes in the channels that control the flow of sodium into the nerve cells and out of them is referred to as "sodium channelopathy".
The Indiana University study found that CBD can directly inhibit the aberrant flow of sodium ions into nerve cells with sodium channelopathies. It is important that CBD does not seem to affect the flow of sodium in healthy nerve cells.
Although CBD has a marked effect on these sodium channelopathies, this does not mean that CBD brings significant benefits to other types of epilepsy.
Other forms of epilepsy are associated with regulatory problems associated with the flow of potassium ions into cells. This type of pediatric epilepsy is resistant to all known therapeutics, including CBD.
A potential pain therapist?
CBD can also be used to relieve pain. In fact, increasing evidence in preclinical laboratory studies indicates that CBD may be useful in the treatment and prevention of neuropathic pain or an increased response due to nerve cell damage. In a mouse model of this type of pain, CBD injections prevented the development of a typical sign of neuropathic pain, the so-called mechanical allodynia. This is the pain sensation due to a non-harmful stimulus, eg. For example, the feeling that clothes are on a skin area that has sunburned. A recent study by McGill University in Montreal, Canada, shows that oral administration of CBD causes the same effects in rats with similar pain.
In both studies, scientists discovered that these effects are likely due to effects on serotonin receptors. A study by scientists from the University of Kentucky suggested that CBD applied to the skin, or transdermal CBD, may reduce inflammation in a rat model of arthritis.
However, further studies from the Temple University laboratory show that CBD does not work for all types of pain when tested on animals.
An important caveat in these findings is that not all compounds that produce effects in rodent studies are effective in humans. In addition, most of these studies examined the effects of CBD injections. So far, there is little evidence of therapeutic effects of either edible or transmucosal substance, administration of a drug via the mucosa, CBD for pain. There is limited evidence for the use of transdermal CBD. Until more scientific studies are conducted, the hype with which CBD can successfully treat various forms of pain in humans is premature.
CBD: Beyond the Lab
Still curious about the hype? Before you go to the local supermarket to buy CBD to run your own trial at home, there are a few more things to keep in mind.
Most CBD products sold in grocery stores are called "hemp-derived." That is, they come from a cannabis plant that is said to contain extremely little THC. Normally, hemp-derived products are made from the stems and roots of the plant. This is in contrast to marijuana, which can contain varying amounts of THC and comes from the flowers of the cannabis plant. Recently, hemp-derived products were removed from the Controlled Substances Act.
However, it remains unclear whether CBD from hemp works in the same way as CBD from marijuana. In addition, the FDA does not approve CBD products as a dietary supplement or the commercialization of health claims. In addition, the Agency prohibits the addition of THC or CBD to foods sold for human or animal consumption in international trade.
As long as there are no medical claims, the FDA allows the use of hemp oil and seeds in cosmetics. However, the usefulness of hemp products in cosmetics still needs to be determined.
Since many of the items on the supermarket shelf are not FDA approved, there is a limited overview of their production and the amount of CBD. If anything, these products are often wrong or misleading. So it's too early to say if CBD is really a rising star or just a fad that burns out and falls to earth.
Editor's note: This article has been updated to correct the company's name, GW Pharmaceuticals, which developed Epidiolex.
Jenny Wilkerson, Assistant Professor of Pharmacodynamics, University of Florida and Lance McMahon, Professor and Chair of Pharmacodynamics, [Florida]
This article has been republished by The Conversation under a Creative Commons license. Read the original article.