Role of cannabinoids in gastrointestinal mucosal defense and inflammation.

“Modulating the activity of the endocannabinoid system influences various gastrointestinal physiological and pathophysiological processes, and cannabinoid receptors as well as regulatory enzymes responsible for the synthesis or degradation of endocannabinoids represent potential targets to reduce the development of gastrointestinal mucosal lesions, hemorrhage and inflammation.

Direct activation of CB1 receptors by plant-derived, endogenous or synthetic cannabinoids effectively reduces both gastric acid secretion and gastric motor activity, and decreases the formation of gastric mucosal lesions induced by stress, pylorus ligation, nonsteroidal anti-inflammatory drugs (NSAIDs) or alcohol, partly by peripheral, partly by central mechanisms.

Similarly, indirect activation of cannabinoid receptors through elevation of endocannabinoid levels by globally acting or peripherally restricted inhibitors of their metabolizing enzymes (FAAH, MAGL) or by inhibitors of their cellular uptake reduced the gastric mucosal lesions induced by NSAIDs in a CB1 receptor-dependent fashion.

Dual inhibition of FAAH and cyclooxygenase induced protection against both NSAID-induced gastrointestinal damage and intestinal inflammation.

Moreover, in intestinal inflammation direct or indirect activation of CB1 and CB2 receptors exerts also multiple beneficial effects.

Namely, activation of both CB receptors was shown to ameliorate intestinal inflammation in various murine colitis models, to decrease visceral hypersensitivity and abdominal pain, as well as to reduce colitis-associated hypermotility and diarrhea.

In addition, CB1 receptors suppress secretory processes and also modulate intestinal epithelial barrier functions. Thus, experimental data suggest that the endocannabinoid system represents a promising target in the treatment of inflammatory bowel diseases, and this assumption is also confirmed by preliminary clinical studies.”

http://www.ncbi.nlm.nih.gov/pubmed/26935536

A Single Intrathecal or Intraperitoneal Injection of CB2 Receptor Agonist Attenuates Bone Cancer Pain and Induces a Time-Dependent Modification of GRK2.

“The objective of this study was to explore the potential role of G-protein-coupled receptor kinase 2 (GRK2) in the progression of cannabinoid 2 receptor (CB2) agonist-induced analgesic effects of bone cancer pain.

The results affirmed CB2 receptor agonists might serve as new treatment targets for bone cancer pain.

Moreover, spinal GRK2 was an important regulator of CB2 receptor agonist-analgesia pathway.”

http://www.ncbi.nlm.nih.gov/pubmed/26935064

Nabilone for the Management of Pain.

“Nabilone, a synthetic cannabinoid, is approved in many countries including, but not limited to, Canada, the United States, Mexico, and the United Kingdom for the treatment of severe nausea and vomiting associated with chemotherapy. Clinical evidence is emerging for its use in managing pain conditions with different etiologies. We review the efficacy and safety of nabilone for various types of pain as well as its abuse potential, precautions and contraindications, and drug interactions; summarize pertinent clinical practice guidelines; and provide recommendations for dosing, monitoring, and patient education.

Nabilone was most commonly used as adjunctive therapy and led to small but significant reductions in pain. The most common adverse drug reactions included euphoria, drowsiness, and dizziness. Nabilone was rarely associated with severe adverse drug reactions requiring drug discontinuation, and the likelihood of abuse was thought to be low. Although the optimal role of nabilone in the management of pain is yet to be determined, certain clinical practice guidelines consider nabilone as a third-line agent.”

http://www.ncbi.nlm.nih.gov/pubmed/26923810

Cannabinoid CB2 receptors are involved in the regulation of fibrogenesis during skin wound repair in mice.

“Studies have shown that cannabinoid CB2 receptors are involved in wound repair, however, its physiological roles in fibrogenesis remain to be elucidated.

In the present study, the capacity of cannabinoid CB2 receptors in the regulation of skin fibrogenesis during skin wound healing was investigated.

These results indicated that cannabinoid CB2 receptors modulate fibrogenesis and the TGF‑β/Smad profibrotic signaling pathway during skin wound repair in the mouse.”

http://www.ncbi.nlm.nih.gov/pubmed/26935001