U.S.: Marijuana Cannabinoids Could Point The Way To First Effective Medication For PTSD
By Steve Elliott
In a first-of-its-kind study on the biochemical impact of psychological trauma, researchers have discovered a connection between the amount of cannabinoid receptors in the human brain and the chronic, disabling condition post-traumatic stress disorder (PTSD).
The findings, from New York University Langone Medical Center, appeared online Tuesday in the journal Molecular Psychiatry, reports Science Daily. They will also be presented this week at the annual meeting of the Society of Biological Psychiatry in San Francisco.
There are a number of treatments using psychotherapy and cognitive behavioral therapy for PTSD patients, but these methods aren't always available, reports Loren Grush at Fox News.
No pharmaceutical treatments have yet been developed to specifically target PTSD.
The NYU Langone Center researchers utilized brain imaging technology to highlight the connection between the number of cannabinoid receptors in the brain and PTSD. The cannabinoid receptors, known as CB1 receptors, are activated in the brain when a person uses marijuana, which can lead to impaired short-term memory and reduced anxiety.
CB1 receptors are part of the body's natural endocannabinoid system, a network of chemicals and signaling pathways in the body which plays a role in memory formation, appetite, pain tolerance and mood. Animal studies have shown that cannabis, along with natural neurotransmitters produced in the brain, can impair memory and reduce anxiety when the activate CB1 receptors in the brain.
The new study is the first to show, through brain imaging, that people with PTSD have remarkably lower concentrations of at least one of these endocannabinoids -- anandamide -- than people without PTSD.
The findings pave the way for development of the first-ever medication designed specifically to treat PTSD, something that researchers say is desperately needed.
"The first line of treatment (for PTSD patients) is selective serotonin re-uptake inhibitors, which is a class of medication generally used with good effects in people with depression," said Dr. Alexander Neumeister, lead author of the study and director of the molecular imaging program in the departments of psychiatry and radiology at NYU School of Medicine.
"These medications do not really do the job for people with PTSD, so clinicians use anything else that is legally available on the market," Dr. Neumeister said. "They often use different classes of medications developed for things like depression, schizophrenia, or bipolar disorder, and overall there's a consensus that these do not work."
"There's not a single pharmacological treatment out there that has been developed specifically for PTSD," Dr. Neumeister said. "That's a problem.
"In fact, we know very well that people with PTSD who use marijuana -- a potent cannabinoid -- often experience more relief from their symptoms than they do from antidepressants and other psychiatric medications," Dr. Neumeister said. "Clearly, there's a very urgent need to develop novel evidence-based treatments for PTSD."
"About eight years ago, the first animal study was published showing that everybody has endogenous cannabinoids, or endocannabinoids, in the brain -- meaning this substance is in the brain of every person," Dr. Neumeister said. "Animal studies have suggested that increasing cannabinoids in the brain helps them to forget painful events and form new memories, so they start to learn to digest what they went through and get over it. We thought this may be relevant to PTSD."
The study divided 60 participants into three groups: those with PTSD; those with a history of trauma but no PTSD; and those with no history or either trauma or PTSD. Participants in all three groups received a radioactive tracer that illuminates CB1 receptors when exposed to PET scans.
Results showed that participants with PTSD, especially women, had more CB1 receptors in brain regions associated with fear and anxiety than volunteers without PTSD. The PTSD group also had less of the neurotransmitter anandamide, an endocannabinoid that binds to the CB1 receptor.
When anandamide levels are low, Dr. Neumeister explained, the brain compensates by increasing the number of CB1 receptors. "This helps the brain utilize the remaining endocannabinoids," he said.
"What is PTSD? It's an illness where people cannot forget what they have experienced," Dr. Neumeister said. "Our findings offer a possible explanation for this phenomenon."
Biological markers of PTSD -- such as these tests for CB1 receptors and anandamide levels -- could dramatically improve diagnosis and treatment for trauma victims, especially since current diagnostics for PTSD rely on subjective measures and patient recall, making it difficult to accurately diagnose the condition or distinguish it from depression and anxiety.
An estimated 20 percent of the 1.7 million men and women who have served in the wars in Iraq and Afghanistan have PTSD, but it is not limited to soldiers. Trauma from sexual and physical abuse, car accidents, natural disasters, and life-threatening medical diagnoses can lead to PTSD; it affects nearly 8 million Americans annually.
"We want to increase the concentration of these endocannabinoids," Dr. Neumeister said. "So we are currently working on the methods to do this, and we have developed a compound that is able to increase the concentration of endocannabinoids without attacking the receptors."
The thing is, we already have a safe, natural and organic way to increase the concentration of cannabinoids in the brain -- it's called smoking pot, and you don't have to pay a big pharmaceutical corporation to do so, at least yet, anyway.
But Neumeister said the compound he's investigating is "very safe" and does not come with the "added health problems" of marijuana use. Without detailing what "health problems" those would those be, exactly (studies have shown that not only does marijuana not harm the lungs or pulmonary system; it actually appears to increase lung health.)