Tag Archives: Cannabinoids

Cannabis constituent synergy in a mouse neuropathic pain model.

Posted on by
Reply

logo

“Cannabis and its psychoactive constituent Δ9-tetrahydrocannabinol (THC) have efficacy against neuropathic pain however, this is hampered by their side-effects. It has been suggested that co-administration with another major constituent cannabidiol (CBD) might enhance the analgesic actions of THC and minimise its deleterious side-effects.

We examined the basis for this phytocannabinoid interaction in a mouse chronic constriction injury (CCI) model of neuropathic pain. Acute systemic administration of THC dose-dependently reduced CCI-induced mechanical and cold allodynia, but also produced motor incoordination, catalepsy and sedation. CBD produced a lesser dose-dependent reduction in allodynia, but did not produce the cannabinoid side-effects. When co-administered in a fixed ratio, THC and CBD produced a biphasic dose-dependent reduction in allodynia. At low doses, the THC:CBD combination displayed a 200-fold increase in anti-allodynic potency, but had lower efficacy compared to that predicted for an additive drug interaction. By contrast, high THC:CBD doses had lower potency, but greater anti-allodynic efficacy compared to that predicted for an additive interaction. Only the high dose THC:CBD anti-allodynia was associated with cannabinoid side-effects and these were similar to those of THC alone. Unlike THC, the low dose THC:CBD anti-allodynia was not cannabinoid receptor mediated.

These findings demonstrate that CBD synergistically enhances the pain relieving actions of THC in an animal neuropathic pain model, but has little impact on the THC-induced side-effects. This suggests that low dose THC:CBD combination treatment has potential in the treatment of neuropathic pain.”

https://www.ncbi.nlm.nih.gov/pubmed/28885457
https://insights.ovid.com/crossref?an=00006396-900000000-99155

Anti-nociceptive interactions between opioids and a cannabinoid receptor 2 agonist in inflammatory pain.

Posted on by
Reply

SAGE Journals

“The cannabinoid 1 receptor and cannabinoid 2 receptor can both be targeted in the treatment of pain; yet, they have some important differences. Cannabinoid 1 receptor is expressed at high levels in the central nervous system, whereas cannabinoid 2 receptor is found predominantly, although not exclusively, outside the central nervous system. The objective of this study was to investigate potential interactions between cannabinoid 2 receptor and the mu-opioid receptor in pathological pain. The low level of adverse side effects and lack of tolerance for cannabinoid 2 receptor agonists are attractive pharmacotherapeutic traits. This study assessed the anti-nociceptive effects of a selective cannabinoid 2 receptor agonist (JWH-133) in pathological pain using mice subjected to inflammatory pain using the formalin test. Furthermore, we examined several ways in which JWH-133 may interact with morphine. JWH-133 produces dose-dependent anti-nociception during both the acute and inflammatory phases of the formalin test. This was observed in both male and female mice. However, a maximally efficacious dose of JWH-133 (1 mg/kg) was not associated with somatic withdrawal symptoms, motor impairment, or hypothermia. After eleven once-daily injections of 1 mg/JWH-133, no tolerance was observed in the formalin test. Cross-tolerance for the anti-nociceptive effects of JWH-133 and morphine were assessed to gain insight into physiologically relevant cannabinoid 2 receptor and mu-opioid receptor interaction. Mice made tolerant to the effects of morphine exhibited a lower JWH-133 response in both phases of the formalin test compared to vehicle-treated morphine-naïve animals. However, repeated daily JWH-133 administration did not cause cross-tolerance for morphine, suggesting opioid and cannabinoid 2 receptor cross-tolerance is unidirectional. However, preliminary data suggest co-administration of JWH-133 with morphine modestly attenuates morphine tolerance. Isobolographic analysis revealed that co-administration of JWH-133 and morphine has an additive effect on anti-nociception in the formalin test. Overall these findings show that cannabinoid 2 receptor may functionally interact with mu-opioid receptor to modulate anti-nociception in the formalin test.”

https://www.ncbi.nlm.nih.gov/pubmed/28879802

http://journals.sagepub.com/doi/10.1177/1744806917728227

 

Intra-cerebral cannabidiol infusion-induced neuroprotection is partly associated with the TNF-α/TNFR1/NF-кB pathway in transient focal cerebral ischaemia.

Posted on by
Reply

Publication Cover

“Stroke is a neurological disease, which, in addition to high mortality, imposes many financial and mental burdens on families and the society.

The main objective of this study was to investigate the effect of cannabidiol (CBD) on one of the major inflammatory pathways in cerebral ischaemia.

RESULTS:

Administration of CBD (100 and 200 ng/rat) caused a significant reduction in infarction, brain oedema, and BBB permeability compared with the vehicle-received group. Down-regulation of TNF-α, TNFR1, and NF-кB expression was also observed by CBD.

CONCLUSION:

The results achieved in this study support the idea that CBD has a cerebroprotective effect (partly through suppression of TNF-α, TNFR1, and NF-кB) on ischaemic injury.”

https://www.ncbi.nlm.nih.gov/pubmed/28872345

http://www.tandfonline.com/doi/abs/10.1080/02699052.2017.1358397?journalCode=ibij20

Clinical and Pre-Clinical Evidence for Functional Interactions of Cannabidiol and Δ9-Tetrahydrocannabinol.

Posted on by
Reply

Image result for neuropsychopharmacology

“The plant Cannabis sativa, commonly called cannabis or marijuana, has been used for its psychotropic and mind-altering side effects for millennia. There has been growing attention in recent years on its potential therapeutic efficacy as municipalities and legislative bodies in the United States, Canada, and other countries grapple with enacting policy to facilitate the use of cannabis or its constituents for medical purposes. There are over 550 chemical compounds and over 100 phytocannabinoids isolated from cannabis, including Δ9-tetrahydrocannabinol (THC) and Cannabidiol (CBD). THC is thought to produce the main psychoactive effects of cannabis, while CBD does not appear to have similar effects. Studies conflict as to whether CBD attenuates or exacerbates the behavioral and cognitive effects of THC. This includes effects of CBD on THC induced anxiety, psychosis and cognitive deficits. In this article, we review the available evidence on the pharmacology and behavioral interactions of THC and CBD from pre-clinical and human studies particularly with reference to anxiety and psychosis like symptoms. Both THC and CBD, as well as other cannabinoid molecules, are currently being evaluated for medicinal purposes, separately and in combination. Future cannabis-related policy decisions should include consideration of scientific findings including the individual and interactive effects of CBD and THC.”

https://www.ncbi.nlm.nih.gov/pubmed/28875990

https://www.nature.com/npp/journal/vaop/naam/abs/npp2017209a.html

Managing neuropathic pain in multiple sclerosis: Pharmacological interventions.

Posted on by
Reply

Image result for University of New South Wales

“Multiple sclerosis (MS) is a chronic inflammatory demyelinating disease of the central nervous system (CNS). Of the plethora of motor and sensory disturbances experienced by sufferers, neuropathic pain is a highly prevalent and debilitating symptom, and at present remains extremely difficult to treat. Common forms of neuropathic pain seen in MS patients include central neuropathic pain, Lhermitte’s phenomenon and trigeminal neuralgia, which are all speculated to arise from specific patterns of lesion formation.

OBJECTIVE:

Efficacious pharmacological interventions for the treatment of neuropathic pain associated with MS are lacking, and have been largely informed by drug trials in peripheral neuropathies and spinal cord injury.

METHOD/RESULTS:

Neuropathic pain in MS is inadequately relieved by conventional analgesics, and first-line therapies are generally comprised of anti-depressive and anti-convulsive drugs. A range of alternatives have been proposed and tested with variable success, including cannabinoids and certain opioid analgesics. Animals with experimental autoimmune encephalomyelitis (EAE), an autoimmune model of MS, also exhibit neuropathic pain symptoms.

CONCLUSION:

Studies aimed at understanding the mechanisms underlying EAE-induced neuropathic pain and investigating the efficacy of novel pharmacological interventions at the animal level offer an exciting area of future research, and may inform future therapeutic options for MS-associated neuropathic pain.”

https://www.ncbi.nlm.nih.gov/pubmed/28875858

 

Topical cannabinoids in dermatology.

Posted on by
Reply

Image result for cutis journal

“Topical cannabinoids are increasingly utilized by dermatology patients for a range of disorders; however, the acceptance of these over-the-counter products has far outpaced scientific investigation into their safety and efficacy. Here, we review the studies of topical cannabinoids in skin conditions and assess their current place in dermatology practice.”

https://www.ncbi.nlm.nih.gov/pubmed/28873100

“The endocannabinoid system of the skin in health and disease: novel perspectives and therapeutic opportunities” https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2757311/

“Cannabinoid system in the skin – a possible target for future therapies in dermatology.” https://www.ncbi.nlm.nih.gov/pubmed/19664006

“Anti-inflammatory cannabinoids for skin diseases”  https://www.endoca.com/blog/discovery/anti-inflammatory-cannabinoids-skin-diseases/

“Topical cannabinoids may help to treat skin diseases”  http://www.medicalnewstoday.com/articles/316968.php

A selective review of medical cannabis in cancer pain management.

Posted on by
Reply

“Insufficient management of cancer-associated chronic and neuropathic pain adversely affects patient quality of life. Patients who do not respond well to opioid analgesics, or have severe side effects from the use of traditional analgesics are in need of alternative therapeutic op-tions.

Anecdotal evidence suggests that medical cannabis has potential to effectively manage pain in this patient population.

This review presents a selection of representative clinical studies, from small pilot studies conducted in 1975, to double-blind placebo-controlled trials conducted in 2014 that evaluated the efficacy of cannabinoid-based therapies containing tetrahydrocannabinol (THC) and cannabidiol (CBD) for reducing cancer-associated pain. A review of literature published on Medline between 1975 and 2017 identified five clinical studies that evaluated the effect of THC or CBD on controlling cancer pain, which have been reviewed and summarised.

Five studies that evaluated THC oil capsules, THC:CBD oromucosal spray (nabiximols), or THC oromucosal sprays found some evidence of cancer pain reduction associated with these therapies. A variety of doses ranging from 2.7-43.2 mg/day THC and 0-40 mg/day CBD were administered. Higher doses of THC were correlated with increased pain relief in some studies. One study found that significant pain relief was achieved in doses as low as 2.7-10.8 mg THC in combination with 2.5-10.0 mg CBD, but there was conflicting evidence on whether higher doses provide superior pain relief. Some reported side effects include drowsiness, hypotension, mental clouding, and nausea and vomiting.

There is evidence suggesting that medical cannabis reduces chronic or neu-ropathic pain in advanced cancer patients.

However, the results of many studies lacked statistical power, in some cases due to limited number of study subjects. Therefore, there is a need for the conduct of further double-blind, placebo-controlled clinical trials with large sample sizes in order to establish the optimal dosage and efficacy of different cannabis-based therapies.”

https://www.ncbi.nlm.nih.gov/pubmed/28866904

http://apm.amegroups.com/article/view/16199

 

Parent use of cannabis for intractable pediatric epilepsy: Everyday empiricism and the boundaries of scientific medicine.

Posted on by
Reply

Social Science & Medicine

“Cannabis is an increasingly sought-after remedy for US children with intractable (biomedically uncontrollable) epilepsy. However, like other complementary-alternative medicine (CAM) modalities, and particularly as a federally illegal, stigmatized substance, it is unsanctioned by mainstream medicine. Parents are largely on their own when it comes to learning about, procuring, dispensing, and monitoring treatments. Exploring how they manage is crucial to better assist them. Moreover, it can illuminate how ‘research’ done on the ground by laypeople variously disrupts and reinforces lay-expert and science-non-science divides. To those ends, in 2016, 25 Southern California parents who used, had used, or sought to use cannabis pediatrically for epilepsy/seizures were interviewed regarding their evidentiary standards, research methods, and aims when trying the drug. Parents generally described their work as experimentation; they saw their efforts as adhering to authorized scientific practices and standards, and as contributing to the authorized medical cannabis knowledge base. Findings subverted assumptions, based on an outdated stereotype of CAM, that cannabis-using parents do not believe in biomedicine. Indeed, parents’ desire for their children’s biomedical demarginalization, combined with biomedical dependency and a high caregiver burden, fueled a collaborative stance. Implications for understanding the boundaries of science are explored, as are norms for parent agency as ill children’s care managers, radicalization among people affected by contested illnesses, and the future of ‘medical marijuana.'”

https://www.ncbi.nlm.nih.gov/pubmed/28865255

http://www.sciencedirect.com/science/article/pii/S0277953617304756?via%3Dihub

 

CHANGES IN THE CANNABINOIDS RECEPTORS IN RATS FOLLOWING TREATMENT WITH ANTIDEPRESSANTS.

Posted on by
Reply

Cover image

“The endocannabinoid (eCB) system plays a significant role in the pathophysiology of depression. The potential participation of this system in the mechanism of action of antidepressants has been highlighted in recent years.

The aim of this study was to investigate the expression of cannabinoid (CB) receptors using Western blot and CB1 receptor density using autoradiography after acute or chronic administration of antidepressant drugs [imipramine (IMI, 15mg/kg), escitalopram (ESC, 10mg/kg) and tianeptine (TIA, 10mg/kg)].

Antidepressants given chronically elevated CB1 receptor density in the cortical structures and hippocampal areas, while a decrease of CB1 receptor density was observed in the striatum after IMI and ESC treatment. The CB1 receptor expression decreases in the dorsal striatum after chronic administration of IMI and ESC or the receptor rise in the hippocampus after chronic ESC and TIA treatment were confirmed using Western blot analyses. An increase in the CB2 receptor expression was observed in the cortical structures and hippocampus after chronic administration of ESC and TIA, while a decrease in this expression was noted in the striatum and cerebellum after chronic IMI treatment.

Our results provide clear evidence that the antidepressant exposures provoke some modulations within the eCB system through CB receptors.”

https://www.ncbi.nlm.nih.gov/pubmed/28866072

http://www.sciencedirect.com/science/article/pii/S0161813X17301717

CB1 Receptors Signaling in the Brain: Extracting Specificity from Ubiquity.

Posted on by
Reply

Related image

“Endocannabinoids (eCBs) are amongst the most ubiquitous signaling molecules in the nervous system. Over the past few decades, observations based on a large volume of work, first examining the pharmacological effects of exogenous cannabinoids, and then the physiological functions of eCBs, have directly challenged long-held and dogmatic views about communication, plasticity and behavior in the Central Nervous System (CNS). The eCBs and their cognate cannabinoid receptors exhibit a number of unique properties that distinguish them from the widely studied classical amino acid transmitters, neuropeptides and catecholamines. Although we now have a loose set of mechanistic rules based on experimental findings, new studies continue to reveal that our understanding of the endocannabinoid system (ECS) is continuously evolving and challenging long-held conventions. Here, we will briefly summarize findings on the current canonical view of the ‘endocannabinoid system’ and will address novel aspects that reveal how a nearly ubiquitous system can determine highly specific functions in the brain. In particular, we will focus on findings that push for an expansion of our ideas around long-held beliefs about eCB signaling that, whilst clearly true, may be contributing to an oversimplified perspective on how cannabinoid signaling at the microscopic level impacts behavior at the macroscopic level.”

https://www.ncbi.nlm.nih.gov/pubmed/28862250

https://www.nature.com/npp/journal/vaop/naam/abs/npp2017206a.html