Cannabinoid actions at TRPV channels: effects on TRPV3 and TRPV4 and their potential relevance to gastrointestinal inflammation.

“Plant cannabinoids, like Δ(9)-tetrahydrocannabinol (THC) and cannabidiol (CBD), activate/desensitize thermosensitive transient receptor potential (TRP) channels of vanilloid type-1 or -2 (TRPV1 or TRPV2). We investigated whether cannabinoids also activate/desensitize two other ‘thermo-TRP’s’, the TRP channels of vanilloid type-3 or -4 (TRPV3 or TRPV4), and if the TRPV-inactive cannabichromene (CBC) modifies the expression of TRPV1-4 channels in the gastrointestinal tract…

CONCLUSIONS:

Cannabinoids can affect both the activity and the expression of TRPV1-4 channels, with various potential therapeutic applications, including in the gastrointestinal tract.”

http://www.ncbi.nlm.nih.gov/pubmed/21726418

(+)-Cannabidiol analogues which bind cannabinoid receptors but exert peripheral activity only.

“We have tested a series of (+)-cannabidiol derivatives… for central and peripheral (intestinal, antiinflammatory and peripheral pain) effects in mice…

We conclude that centrally inactive (+)-cannabidiol analogues should be further developed as antidiarrheal, antiinflammatory and analgesic drugs for gastrointestinal and other peripheral conditions.”

http://www.ncbi.nlm.nih.gov/pubmed/15588739

Pro-resolution, protective and anti-nociceptive effects of a cannabis extract in the rat gastrointestinal tract.

“Cannabis is widely used for treating a number of gastrointestinal ailments…

In the present study, we tested the effects (in rats) of a simple extract of medicinal cannabis (called “MFF”) for its ability to promote resolution of colitis…

These results demonstrate that a simple extract of medicinal cannabis can significantly enhance resolution of inflammation and injury, as well as prevent injury, in the gastrointestinal tract. Interestingly, different cannabinoid receptors were involved in some of the effects. MFF may serve as the basis for a simple preparation of cannabis that would produce beneficial effects in the GI tract with reduced systemic toxicity.”

http://www.ncbi.nlm.nih.gov/pubmed/23756391

Selective inhibition of FAAH produces antidiarrheal and antinociceptive effect mediated by endocannabinoids and cannabinoid-like fatty acid amides.

“The endogenous cannabinoid system (ECS) plays a crucial role in multiple physiological processes in the central nervous system and in the periphery. The discovery that selective cannabinoid (CB) receptor agonists exert a potent inhibitory action on gastrointestinal (GI) motility and pain has placed the ECS in the center of attention as a possible target for the treatment of functional GI diseases…

These data expand our understanding of the ECS function and provide a novel framework for the development of future potential treatments of functional GI disorders.”

http://www.ncbi.nlm.nih.gov/pubmed/24460851

Therapeutic potential of cannabinoid medicines.

Drug Testing and Analysis

“Cannabis was extensively used as a medicine throughout the developed world in the nineteenth century but went into decline early in the twentieth century ahead of its emergence as the most widely used illicit recreational drug later that century. Recent advances in cannabinoid pharmacology alongside the discovery of the endocannabinoid system (ECS) have re-ignited interest in cannabis-based medicines.

The ECS has emerged as an important physiological system and plausible target for new medicines. Its receptors and endogenous ligands play a vital modulatory role in diverse functions including immune response, food intake, cognition, emotion, perception, behavioural reinforcement, motor co-ordination, body temperature, wake/sleep cycle, bone formation and resorption, and various aspects of hormonal control. In disease it may act as part of the physiological response or as a component of the underlying pathology.

In the forefront of clinical research are the cannabinoids delta-9-tetrahydrocannabinol and cannabidiol, and their contrasting pharmacology will be briefly outlined. The therapeutic potential and possible risks of drugs that inhibit the ECS will also be considered. This paper will then go on to review clinical research exploring the potential of cannabinoid medicines in the following indications: symptomatic relief in multiple sclerosis, chronic neuropathic pain, intractable nausea and vomiting, loss of appetite and weight in the context of cancer or AIDS, psychosis, epilepsy, addiction, and metabolic disorders.”

http://www.ncbi.nlm.nih.gov/pubmed/24006213

http://onlinelibrary.wiley.com/doi/10.1002/dta.1529/abstract

Acute Δ9-tetrahydrocannabinol blocks gastric hemorrhages induced by the nonsteroidal anti-inflammatory drug diclofenac sodium in mice.

“Nonsteroidal anti-inflammatory drugs (NSAIDs), which are among the most widely used analgesics in the world, cause gastrointestinal inflammation that is potentially life-threatening.

Although inhibitors of endocannabinoid catabolic enzymes protect against gastropathy in fasted NSAID-treated mice, the gastroprotective effects of Δ9-tetrahydrocannabinol (THC), the primary psychoactive component of marijuana, have yet to be investigated…

 These data indicate that the phytocannabinoid Δ9-THC protects against diclofenac-induced gastric inflammatory tissue damage at doses insufficient to cause common cannabinoid side effects.”

http://www.ncbi.nlm.nih.gov/pubmed/23769745

Intractable nausea and vomiting due to gastrointestinal mucosal metastases relieved by tetrahydrocannabinol (dronabinol).

“Four years following resection of a Clark’s level IV malignant melanoma, a 50-year-old man developed widespred metastatic disease involving the liver, bones, brain, gastrointestinal mucosa, and lungs. One week after whole brain radiation therapy, he was admitted to the hospital for nausea, vomiting, and pain.

He was treated with several antiemetic drugs, but it was not until dronabinol was added that the nausea and vomiting stopped.

Dronabinol was an effective antiemetic used in combination with prochlorperazine in nausea and vomiting unresponsive to conventional antiemetics.”

http://www.ncbi.nlm.nih.gov/pubmed/9392925

Psychoactive cannabinoids reduce gastrointestinal propulsion and motility in rodents.

“Marijuana has been reported to be an effective antinauseant and antiemetic in patients receiving cancer chemotherapy.

Whether this is due to psychological changes, central antiemetic properties and/or direct effects on gastrointestinal (GI) function is not known. The purpose of these investigations was to determine whether the major constituents of marijuana and the synthetic cannabinoid nabilone have any effects on GI function which can be detected in rodent models of GI transit and motility. Intravenous delta 9-tetrahydrocannabinol (delta 9-THC) slowed the rate of gastric emptying and small intestinal transit in mice and in rats. Delta 9,11-THC, cannabinol and nabilone given i.v. also inhibited small intestinal transit in mice, but were less effective in reducing gastric emptying. Cannabidiol given i.v. had no effect on gastric emptying or intestinal transit. Those cannabinoids which inhibited GI transit did so at doses equal to, or lower, than those reported to produce central nervous system activity. In rats, delta 9-THC produced greater inhibition of gastric emptying and small intestinal transit than large bowel transit, indicating a selectivity for the more proximal sections of the gut. In addition, i.v. delta 9-THC decreased the frequency of both gastric and intestinal contractions without altering intraluminal pressure. Such changes probably reflect a decrease in propulsive activity, without change in basal tone.

These data indicate that delta 9-THC, delta 9,11-THC, cannabinol and nabilone (but not cannabidiol) exert an inhibitory effect on GI transit and motility in rats.”

http://www.ncbi.nlm.nih.gov/pubmed/2542532

Pharmacological synergism between cannabinoids and paclitaxel in gastric cancer cell lines.

“Orally applicable Delta9-tetrahydrocannabinol and its synthetic derivatives have been used as antiemetic drugs during chemotherapy in cancer patients.

 However, it is not well known how cannabinoids influence the effects of chemotherapeutic agents on malignant tumors. In this study, we investigated how the endogenous cannabinoid anandamide (AEA) changes the effect of paclitaxel on gastric cancer cell lines.

 In the human gastric cancer cell line, HGC-27, which express cannabinoid receptor 1 (CB1), AEA stimulated proliferation at concentrations under 1 microM, while it strongly suppressed proliferation through the induction of apoptosis at 10 microM. This bimodal effect was reproduced by a selective CB1 agonist, arachidonyl-2-chloroethylamide, although the effects were less marked. When AEA was used with paclitaxel, AEA at 10 microM synergistically enhanced the cytotoxic effect of paclitaxel, whereas it showed no significant effect at lower concentrations. Flow cytometric analysis revealed that addition of 10 microM AEA synergistically enhanced paclitaxel-induced apoptosis, possibly through the activation of caspase-3, -8, and -9.

Our results suggest that cannabinoids could be a good palliative agent for cancer patients receiving paclitaxel.”

http://www.ncbi.nlm.nih.gov/pubmed/19394652

Effect of a synthetic cannabinoid agonist on the proliferation and invasion of gastric cancer cells.

“Although cannabinoids are associated with antineoplastic activity in a number of cancer cell types, the effect in gastric cancer cells has not been clarified. In the present study, we investigated the effects of a cannabinoid agonist on gastric cancer cell proliferation and invasion.

The cannabinoid agonist WIN 55,212-2 inhibited the proliferation of human gastric cancer cells in a dose-dependent manner and that this effect was mediated partially by the CB(1) receptor. We also found that WIN 55,212-2 induced apoptosis and down-regulation of the phospho-AKT expression in human gastric cancer cells. Furthermore, WIN 55,212-2 treatment inhibited the invasion of gastric cancer cells, and down-regulated the expression of MMP-2 and VEGF-A through the cannabinoid receptors.

Our results open the possibilities in using cannabinoids as a new gastric cancer therapy.”

http://www.ncbi.nlm.nih.gov/pubmed/20336665