The endocannabinoid system as a target for addiction treatment: Trials and tribulations.

“Addiction remains a major public health concern, and while pharmacotherapies can be effective, clinicians are limited by the paucity of existing interventions. Endocannabinoid signaling is involved in reward and addiction, which raises the possibility that drugs targeting this system could be used to treat substance use disorders. This review discusses findings from randomized controlled trials evaluating cannabinergic medications for addiction. Current evidence suggests that pharmacotherapies containing delta-9-tetrahydrocannabinol, such as dronabinol and nabiximols, are effective for cannabis withdrawal. Dronabinol may also reduce symptoms of opioid withdrawal. The cannabinoid receptor 1 (CB1) inverse agonist rimonabant showed promising effects for smoking cessation but also caused psychiatric side effects and currently lacks regulatory approval. Few trials have investigated cannabinergic medications for alcohol use disorder. Overall, the endocannabinoid system remains a promising target for addiction treatment. Development of novel medications such as fatty acid amide hydrolase inhibitors and neutral CB1 antagonists promises to extend the range of available interventions.” https://www.ncbi.nlm.nih.gov/pubmed/28564576 http://www.sciencedirect.com/science/article/pii/S0028390817302563]]>

Cannabinoid CB1/CB2 receptor agonists attenuate hyperactivity and body weight loss in a rat model of activity-based anorexia.

“Anorexia nervosa (AN) is a serious psychiatric condition characterized by excessive body weight loss and disturbed perceptions of body shape and size, often associated with excessive physical activity. There is currently no effective drug-related therapy of this disease and this leads to high relapse rate. Clinical data suggest that a promising therapy to treat and reduce reoccurrence of AN may be based on the use of drugs that target the endocannabinoid (EC) system, which appears dysregulated in AN patients.

Our data show that subchronic treatment with both the CB1/CB2 receptor natural agonist Δ9-tetrahydrocannabinol and the synthetic CB1/CB2 receptor agonist CP-55,940 significantly reduced body weight loss and running wheel activity in ABA rats. These behavioral effects were accompanied by an increase in leptin signaling and a decrease in plasma levels of corticosterone.

Taken together, our results further demonstrate EC system involvement in AN pathophysiology and that strategies which modulate EC signaling are useful to treat this disorder, specifically in patients where physical hyperactivity plays a central role in its progression and maintenance.” https://www.ncbi.nlm.nih.gov/pubmed/28561272 http://onlinelibrary.wiley.com/doi/10.1111/bph.13892/abstract]]>

Nonopioid placebo analgesia is mediated by CB1 cannabinoid receptors.

Image result for nature journal “Placebo analgesia is mediated by both opioid and nonopioid mechanisms, but so far nothing is known about the nonopioid component. Here we show that the specific CB1 cannabinoid receptor antagonist 5-(4-chlorophenyl)-1-(2,4-dichloro-phenyl)-4-methyl-N-(piperidin-1-yl)-1H-pyrazole-3-carboxamide (rimonabant or SR141716) blocks nonopioid placebo analgesic responses but has no effect on opioid placebo responses. These findings suggest that the endocannabinoid system has a pivotal role in placebo analgesia in some circumstances when the opioid system is not involved.”
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