IACM-Bulletin of May 22, 2011

Science — THC effective in trichotillomania symptoms in a pilot study

An open clinical study with patients suffering from trichotillomania, who received oral dronabinol (THC), was conducted at the Department of Psychiatry of the University of Minnesota in Minneapolis, USA. Trichotillomania is an impulse control disorder and characterized by the compulsive urge to pull out one's own hair leading to noticeable hair loss, distress, and social or functional impairment. It is often chronic and difficult to treat. Fourteen female subjects with a mean age of 33 years with trichotillomania were enrolled in the 12-week study. Doses ranged from 2.5-15 mg THC daily. The primary outcome measure was change from baseline to study endpoint on the so-called MGH-HP Scale, which measures the intensity of symptoms in trichotillomania. In order to evaluate effects on cognition, subjects underwent pre- and post-treatment assessments using objective computerized neurocognitive tests.

Twelve of the 14 subjects completed the whole study. MGH-HPS scores decreased statistically significant from a mean of 16.5 at baseline to 8.7 at study endpoint. Nine (64.3 per cent) subjects responded to the treatment with a reduction of more than 35 per cent on the MGH-HPS and "much or very much improved" on a scale for the global impression. The mean effective dose was 11.6 mg per day. The medication was well-tolerated, with no significant deleterious effects on cognition. Authors concluded that "pharmacological modulation of the cannabinoid system may prove useful in controlling a range of compulsive behaviors."

(Source: Grant JE, Odlaug BL, Chamberlain SR, Kim SW. Dronabinol, a cannabinoid agonist, reduces hair pulling in trichotillomania: a pilot study. Psychopharmacology (Berl). 2011 May 19. [in press])

USA — Delaware becomes the 16th state to legalize the medical use of cannabis

On 13 May Governor Jack Markell signed legislation authorizing cannabis growing, distribution and use for limited medical purposes making Delaware the 16th state of the USA to allow the medical use of cannabis. It is expected that qualified patients will be able to get cannabis within one year. The law initiates a one-year regulatory and licensing process for three not-for-profit dispensaries that will be authorized to sell cannabis to patients.

Under the new law, physicians could recommend cannabis for patients suffering from cancer, HIV/AIDS, multiple sclerosis, amyotrophic lateral sclerosis (ALS), Alzheimer’s disease and post-traumatic stress disorder. People with other chronic disease or debilitating medical conditions could qualify if other medicines or surgical procedures have failed to relieve their pain, reduced seizures, severe or persistent muscle spasms and nausea. Physicians and patients would have to have a “bona fide physician-patient relationship” and other medical treatments would have to be exhausted before cannabis is recommended, according to the legislation. Qualified patients who get a doctor's recommendation and a state-issued identification card will be able to purchase up to 6 ounces (about 170 grams) of cannabis at one of the dispensaries.

More at:

- http://www.delawareonline.com/apps/pbcs.dll/article?AID=2011110513020

- http://www.delawareonline.com/apps/pbcs.dll/article?AID=2011110511044

(Sources: Delaware Online of 11 and 13 May 2011)

News in brief

USA — Maryland

On 10 May Maryland adopted a law that attempts to improve the current law, which allows for a "medical necessity" defence before the courts but can still result in a misdemeanour conviction and a 100 Dollar fine. The new law is aimed at removing the misdemeanour conviction, but patients, who use cannabis for medical purposes, can still be forced to pay a punitive fine. "The patient community welcomes improvements to Maryland's medical marijuana law," said Kristen Ford of Americans for Safe Access. "But, because patients are still forced to undergo arrest and criminal prosecution and may sustain punitive fines, the law falls short of the basic protections offered in all other medical marijuana states." (Source: Americans for Safe Access of 11 May 2011)

Science — Epilepsy

According to research at the Radboud University in Nijmegen, The Netherlands, the endocannabinoid system protects against spontaneous seizures. The scientists blocked this system with the cannabinoid receptor antagonist rimonabant in 13 rats for three weeks. In three rats convulsive seizures where observed in the limbic region of the brain after 5 to 8 days. (Source: van Rijn CM, et al. Pharmacol Rep 2011;63(1):165-8.)

Science — Pain

Researchers at Huazhong University of Science and Technology in Wuhan, China, investigated the inhibitory effects of cannabinoids on vanilloid 1 receptors. They used the synthetic cannabinoid WIN 55,212-2 to study the mechanisms of action of peripheral cannabinoids in pain relieving actions on trigeminal ganglion nerve cells. (Source: Wang W, et al. Neurol Sci. 2011 May 17. [in press])

Science — Breast cancer

According to research at the Beth Israel Deaconess Medical Center in Boston, USA, the non-psychotropic cannabinoid cannabidiol (CBD) induces programmed cell death in breast cancer cells by coordinating the crosstalk between apoptosis and autophagy. CBD increased the generation of reactive oxygen species. (Source: Shrivastava A, et al. Mol Cancer Ther. 2011 May 12. [in press])

Science — Aging

Restriction of food intake is a robust means of extending lifespan and postponing age-related disease in many species, including yeast, nematode worms, flies and rodents. Researchers at Buck Institute for Research on Aging in Novato, USA, demonstrated that N-acylethanolamines, which includes the endocannabinoid anandamide, are involved in the process of lifespan extension in a nematode worm (C. elegans). (Source: Lucanic M, et al. Nature 2011;473(7346):226-9.)

Science — Inflammation of the bowel

According to a research group in Brussels, Belgium, increasing the levels of the endocannabinoid 2-AG (2-arachidonoylglycerol) reduced colitis and related systemic inflammation in mice. 2-AG levels were increased by inhibiting monoacylglycerol lipase (MAGL), the primary enzyme responsible for the degradation of 2-AG. (Source: Alhouayek M, et al. FASEB J. 2011 May 6. [in press])

Science — Neuropathic pain

According to research at the University of Georgia in Athens, USA, rats self-administer a synthetic CB2 receptor agonist (AM1241) to reduce neuropathic pain. Neuropathic pain was produced by nerve injury and rats could self-administer the cannabinoid by pressing down a lever. (Source: Gutierrez T, et al. Pain. 2011 May 6. [in press])

Science — Depression

According to research at the University of Maharastra, India, the endocannabinoid system is involved in the antidepressant effects of fluoxetine, a broadly used antidepressant. A CB1 receptor antagonist blocked the effects of fluoxetine. Scientists concluded that "the study indicates an interaction between endocannabinoid and serotonergic system in regulation of depressive and compulsive-like behavior." (Source: Umathe SN, et al. Behav Brain Res. 2011 Apr 28. [in press])

Science — Alzheimer's disease

According to research at the University of California in Irvine, USA, certain brain regions (mid frontal and temporal cortex) of subjects with Alzheimer's disease contain lower levels of the endocannabinoid anandamide than control subjects. Scientists concluded from their study that an impairment in brain anandamide mobilization caused by the amyloid-beta peptide, which is toxic for nerve cells, contributes to cognitive dysfunction in Alzheimer's disease. (Source: Jung KM, et al. Neurobiol Aging. 2011 May 3. [in press])