The endogenous cannabinoid system protects against colonic inflammation

“Excessive inflammatory responses can emerge as a potential danger for organisms’ health.

Our results indicate that the endogenous cannabinoid system represents a promising therapeutic target for the treatment of intestinal disease conditions characterized by excessive inflammatory responses.

The major active constituent of the plant Cannabis sativa (marijuana), Δ9-tetrahydrocannabinol, and a variety of natural and synthetic cannabinoids have been shown to possess antinociceptive and anti-inflammatory activities.

For millennia, Cannabis preparations have been used in folk medicine for the treatment of a wide variety of disorders, including those affecting the gastrointestinal tract. A century ago, extracts of Cannabis were used in the US to treat gastrointestinal pain of different origins, gastroenteritis, and diarrhea. There are also anecdotal reports suggesting that marijuana may be effective in alleviating symptoms of Crohn disease.

In conclusion, this study shows that the endogenous cannabinoid system is physiologically involved in the protection against excessive inflammation in the colon, both by dampening smooth muscular irritation caused by inflammation and by controlling cellular pathways leading to inflammatory responses.

These results strongly suggest that modulation of the physiological activity of the endogenous cannabinoid system during colonic inflammation might be a promising therapeutic tool for the treatment of several diseases characterized by inflammation of the gastrointestinal tract.”

https://www.jci.org/articles/view/19465

“A mouse study demonstrated that endogenous cannabinoid system signaling is likely to provide intrinsic protection against colonic inflammation. As a result, a hypothesis that phytocannabinoids and endocannabinoids may be useful in the risk reduction and treatment of colorectal cancer has been developed.” http://www.cancer.gov/about-cancer/treatment/cam/hp/cannabis-pdq#section/_7

Therapeutic potential of cannabinoids in trigeminal neuralgia.

“Trigeminal neuralgia is a disorder of paroxysmal and severely disabling facial pain and continues to be a real therapeutic challenge to the clinicians. While the exact cause and pathology of this disorder is uncertain, it is thought that trigeminal neuralgia caused by irritation of the trigeminal nerve. This irritation results from damage due to the change in the blood vessels, the presence of a tumor or other lesions that cause the compression of the trigeminal root.

The pain of trigeminal neuralgia is characterized by unilateral pain attacks that start abruptly and last for varying periods of time from minutes to hours. The quality of pain is usually sharp, stabbing, lancinating, and burning. The attacks are initiated by mild stimuli such as light touch of the skin, eating, chewing, washing the face, brushing the teeth, and exposure to wind.

Although antiepileptic drug therapy may be beneficial in the treatment of trigeminal neuralgia, up to one-half of the patients become refractory or intolerant to these medications. At present there are few other effective drugs. In cases of lacking effect after pharmacotherapy, surgical options may be considered.

Currently there is growing amount of evidence to suggest that the psychoactive ingredient in cannabis and individual cannabinoids may be effective in alleviating neuropathic pain and hyperalgesia. Evidence suggests that cannabinoids may prove useful in pain modulation by inhibiting neuronal transmission in pain pathways.

Considering the pronounced antinociceptive effects produced by cannabinoids, they may be a promising therapeutic approach for the clinical management of trigeminal neuralgia.”

http://www.ncbi.nlm.nih.gov/pubmed/15578967

PnPP-19, a spider toxin analogue, induces peripheral antinociception through opioid and cannabinoid receptors and inhibition of Neutral endopeptidase.

“The synthetic peptide PnPP-19 has been studied as a new drug candidate to treat erectile dysfunction. However, PnTx2-6, the spider toxin from which the peptide was designed, induces hyperalgesia. Therefore, we intended to investigate the role of PnPP-19 in the nociceptive pathway.

Antinociception induced by PnPP-19 might involve the inhibition of NEP and activation of CB1 , μ- and δ-opioid receptors. Our data provide a comprehension of the antinociceptive effect induced by PnPP-19 and it should be useful as a new antinociceptive drug candidate.”

http://www.ncbi.nlm.nih.gov/pubmed/26947933

Combined treatment with morphine and Δ9-tetrahydrocannibinol (THC) in rhesus monkeys: antinociceptive tolerance and withdrawal.

“Opioid receptor agonists are effective for treating pain; however, tolerance and dependence can develop with repeated treatment. Combining opioids with cannabinoids can enhance their analgesic potency…

These results demonstrate that antinociceptive tolerance is greater during treatment with the mixture, and although treatment conditions were sufficient for dependence to development on morphine, withdrawal was not markedly altered by concurrent treatment with THC.

Thus, THC can enhance some (antinociception, tolerance) but not all (dependence) effects of morphine.”

http://www.ncbi.nlm.nih.gov/pubmed/26937020

The selective monoacylglycerol lipase inhibitor MJN110 produces opioid sparing effects in a mouse neuropathic pain model.

“Serious clinical liabilities associated with the prescription of opiates for pain control include constipation, respiratory depression, pruritus, tolerance, abuse, and addiction.

A recognized strategy to circumvent these side effects is to combine opioids with other antinociceptive agents.

The combination of opiates with the primary active constituent of cannabis, Δ9-tetrahydrocannabinol, produces enhanced antinociceptive actions, suggesting that cannabinoid receptor agonists can be opioid sparing…

Here, we tested whether elevating the endogenous cannabinoid 2-arachidonylglycerol (2-AG) through the inhibition of its primary hydrolytic enzyme monoacylglycerol lipase (MAGL), will produce opioid sparing effects…

These findings, taken together, suggest that MAGL inhibition produces opiate sparing events with diminished tolerance, constipation, and cannabimemetic side effects.”

http://www.ncbi.nlm.nih.gov/pubmed/26791602

http://www.thctotalhealthcare.com/category/pain-2/

Beneficial effects of a Cannabis sativa extract treatment on diabetes-induced neuropathy and oxidative stress.

“Neuropathy is the most common complication of diabetes and it is still considered to be relatively refractory to most of the analgesics. The aim of the present study was to explore the antinociceptive effect of a controlled cannabis extract (eCBD) in attenuating diabetic neuropathic pain.

These findings highlighted the beneficial effects of cannabis extract treatment in attenuating diabetic neuropathic pain, possibly through a strong antioxidant activity and a specific action upon nerve growth factor.”

http://www.ncbi.nlm.nih.gov/pubmed/19441010

Microinjection of orexin-A into the rat locus coeruleus nucleus induces analgesia via cannabinoid type-1 receptors.

“Locus coeruleus (LC) nucleus is involved in noradrenergic descending pain modulation.

LC receives dense orexinergic projections from the lateral hypothalamus. Orexin-A and -B are hypothalamic peptides which modulate a variety of brain functions via orexin type-1 (OX1) and orexin type-2 (OX2) receptors.

Previous studies have shown that activation of OX1 receptors induces endocannabinoid synthesis and alters synaptic neurotransmission by retrograde signaling via affecting cannabinoid type-1 (CB1) receptors.

In the present study the interaction of orexin-A and endocannabinoids was examined at the LC level in a rat model of inflammatory pain…

This data show that, activation of OX1 receptors in the LC can induce analgesia and also the blockade of OX1 or CB1 receptors is associated with hyperalgesia during formalin test.

Our findings also suggest that CB1 receptors may modulate the analgesic effect of orexin-A.

These results outline a new mechanism by which orexin-A modulates the nociceptive processing in the LC nucleus.”

http://www.ncbi.nlm.nih.gov/pubmed/26254729

Cannabinoids blocks tactile allodynia in diabetic mice without attenuation of its antinociceptive effect.

“Diabetic neuropathic pain is one of the most commonly encountered neuropathic pain syndromes.

It is well known that diabetic animals are less sensitive to the analgesic effect of morphine, and opioids are found to be ineffective in the treatment of diabetic neuropathic pain.

Cannabinoids are promising drugs and they share a similar pharmacological properties with opioids.

It has been reported that cannabinoid analgesia remained intact and to be effective in some models of nerve injury.

Thus, we investigated antinociceptive efficacy and the effects of cannabinoids on behavioral sign of diabetic neuropathic pain in diabetic mice by using WIN 55, 212-2, a cannabinoid receptor agonist.

This study suggests that cannabinoids have a potential beneficial effect on experimental diabetic neuropathic pain.”

http://www.ncbi.nlm.nih.gov/pubmed/15342139

Cross-tolerance to cannabinoids in morphine-tolerant rhesus monkeys.

“Opioids remain the drugs of choice for treating moderate to severe pain, although adverse effects limit their use. Therapeutic utility might be improved by combining opioids with other drugs to enhance analgesic effects, but only if adverse effects are not similarly changed.

Cannabinoids have been shown to enhance the antinociceptive potency of opioids without increasing other effects; this study examined whether the effectiveness of cannabinoids is altered in morphine-dependent monkeys.

Tolerance developed to the antinociceptive effects of morphine and cross-tolerance developed to cannabinoids under conditions that produced modest physical dependence.

Compared with the doses examined in this study, much smaller doses of opioids have antinociceptive effects when given with cannabinoids; it is possible that tolerance will not develop to chronic treatment with opioid/cannabinoid mixtures.”

http://www.ncbi.nlm.nih.gov/pubmed/26202613

Coadministration of indomethacin and minocycline attenuates established paclitaxel-induced neuropathic thermal hyperalgesia: Involvement of cannabinoid CB1 receptors.

“Taxanes such as paclitaxel, which are chemotherapeutic drugs, cause dose-dependent painful neuropathy in some patients.

We investigated whether coadministration of minocycline and indomethacin produces antinociceptive effects in mice with paclitaxel-induced neuropathic thermal hyperalgesia and if the cannabinoid system is involved…

In conclusion our results indicate that coadministration of minocycline and indomethacin abrogates established paclitaxel-induced neuropathic thermal hyperalgesia in mice, and the potentiation of the antinociceptive effects of this combination involves the cannabinoid system.”