Phytocannabinoids in Neurological Diseases: Could They Restore a Physiological GABAergic Transmission?

Posted on January 29, 2020 by David

“γ-Aminobutyric acid type A receptors (GABA_ARs) are the main inhibitory mediators in the central nervous system (CNS). GABA_ARs are pentameric ligand gated ion channels, and the main subunit composition is usually 2α2βγ, with various isotypes assembled within a set of 19 different subunits. The inhibitory function is mediated by chloride ion movement across the GABA_ARs, activated by synaptic GABA release, reducing neuronal excitability in the adult CNS. Several studies highlighted the importance of GABA-mediated transmission during neuro-development, and its involvement in different neurological and neurodevelopmental diseases, from anxiety to epilepsy. However, while it is well known how different classes of drugs are able to modulate the GABA_ARs function (benzodiazepines, barbiturates, neurosteroids, alcohol), up to now little is known about GABA_ARs and cannabinoids interaction in the CNS. Endocannabinoids and phytocannabinoids are lately emerging as a new class of promising drugs for a wide range of neurological conditions, but their safety as medication, and their mechanisms of action are still to be fully elucidated. In this review, we will focus our attention on two of the most promising molecules (Δ9-tetrahydrocannabinol; Δ9-THC and cannabidiol; CBD) of this new class of drugs and their possible mechanism of action on GABA_ARs.”

https://www.ncbi.nlm.nih.gov/pubmed/31979108

https://www.mdpi.com/1422-0067/21/3/723

The Endocannabinoid System: A Target for Cancer Treatment.

Posted on January 26, 2020 by David

“In recent years, the endocannabinoid system has received great interest as a potential therapeutic target in numerous pathological conditions.

Cannabinoids have shown an anticancer potential by modulating several pathways involved in cell growth, differentiation, migration, and angiogenesis.

However, the therapeutic efficacy of cannabinoids is limited to the treatment of chemotherapy-induced symptoms or cancer pain, but their use as anticancer drugs in chemotherapeutic protocols requires further investigation.

In this paper, we reviewed the role of cannabinoids in the modulation of signaling mechanisms implicated in tumor progression.”

https://www.ncbi.nlm.nih.gov/pubmed/31979368

https://www.mdpi.com/1422-0067/21/3/747

“In addition to the symptomatic therapy of cancer patients, the antitumor effects of cannabinoids (whether in monotherapy or in combination with other cancer therapies) have promising potential in the treatment of cancer patients.” https://www.ncbi.nlm.nih.gov/pubmed/31950844
“In addition to the well-known palliative effects of cannabinoids on some cancer-associated symptoms, a large body of evidence shows that these molecules can decrease tumour growth in animal models of cancer. In addition, cannabinoids inhibit angiogenesis and decrease metastasis in various tumour types in laboratory animals. Thus, numerous studies have provided evidence that thc and other cannabinoids exhibit antitumour effects in a wide array of animal models of cancer.” https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4791144/

“Antitumour actions of cannabinoids.” https://www.ncbi.nlm.nih.gov/pubmed/30019449

“The endocannabinoid system as a target for the development of new drugs for cancer therapy” https://www.ncbi.nlm.nih.gov/pubmed/12723496

“Cannabinoids as Anticancer Drugs.” https://www.ncbi.nlm.nih.gov/pubmed/28826542

http://www.thctotalhealthcare.com/category/cancer/

Allosteric Cannabinoid Receptor 1 (CB1) Ligands Reduce Ocular Pain and Inflammation.

Posted on January 25, 2020 by David

“Cannabinoid receptor 1 (CB1) activation has been reported to reduce transient receptor potential cation channel subfamily V member 1 (TRPV1)-induced inflammatory responses and is anti-nociceptive and anti-inflammatory in corneal injury.

We examined whether allosteric ligands, can modulate CB1 signaling to reduce pain and inflammation in corneal hyperalgesia.

Corneal hyperalgesia was generated by chemical cauterization of cornea in wildtype and CB2 knockout (CB2^-/-) mice. The novel racemic CB1 allosteric ligand GAT211 and its enantiomers GAT228 and GAT229 were examined alone or in combination with the orthosteric CB1 agonist Δ⁸-tetrahydrocannabinol (Δ⁸-THC). Pain responses were assessed following capsaicin (1 µM) stimulation of injured corneas at 6 h post-cauterization. Corneal neutrophil infiltration was also analyzed. GAT228, but not GAT229 or GAT211, reduced pain scores in response to capsaicin stimulation.

Combination treatments of 0.5% GAT229 or 1% GAT211 with subthreshold Δ⁸-THC (0.4%) significantly reduced pain scores following capsaicin stimulation. The anti-nociceptive effects of both GAT229 and GAT228 were blocked with CB1 antagonist AM251, but remained unaffected in CB2^-/- mice. Two percent GAT228, or the combination of 0.2% Δ⁸-THC with 0.5% GAT229 also significantly reduced corneal inflammation.

CB1 allosteric ligands could offer a novel approach for treating corneal pain and inflammation.”

https://www.ncbi.nlm.nih.gov/pubmed/31968549

https://www.mdpi.com/1420-3049/25/2/417

Microglial Phenotypes and Their Relationship to the Cannabinoid System: Therapeutic Implications for Parkinson’s Disease.

Posted on January 25, 2020 by David

Image result for molecules journal “Parkinson’s disease is a neurodegenerative disorder, the motor symptoms of which are associated classically with Lewy body formation and nigrostriatal degeneration.

Neuroinflammation has been implicated in the progression of this disease, by which microglia become chronically activated in response to α-synuclein pathology and dying neurons, thereby acquiring dishomeostatic phenotypes that are cytotoxic and can cause further neuronal death.

Microglia have a functional endocannabinoid signaling system, expressing the cannabinoid receptors in addition to being capable of synthesizing and degrading endocannabinoids. Alterations in the cannabinoid system-particularly an upregulation in the immunomodulatory CB₂ receptor-have been demonstrated to be related to the microglial activation state and hence the microglial phenotype.

This paper will review studies that examine the relationship between the cannabinoid system and microglial activation, and how this association could be manipulated for therapeutic benefit in Parkinson’s disease.”

https://www.ncbi.nlm.nih.gov/pubmed/31973235

“Microglia activation states and cannabinoid system: Therapeutic implications. There is accumulating evidence indicating that cannabinoids (CBs) might serve as a promising tool to modify the outcome of inflammation, especially by influencing microglial activity. Microglia has a functional endocannabinoid (eCB) signaling system, composed of cannabinoid receptors and the complete machinery for the synthesis and degradation of eCBs. These actions make CBs a promising therapeutic tool to avoid the detrimental effects of inflammation and possibly paving the way to target microglia in order to generate a reparative milieu in neurodegenerative diseases.” https://www.ncbi.nlm.nih.gov/pubmed/27373505

“These findings imply that a hypofunction or a dysregulation of the endocannabinoid system may be responsible for some of the symptoms of these diseases. Scientific evidence shows that cannabis can provide symptomatic relief in several neurodegenerative diseases.” https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4070159/

“Cannabinoids can have neuroprotective effects, and this can be exploited for therapeutic strategies against neurodegenerative diseases” http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3243800/

The effect of orally administered dronabinol on optic nerve head blood flow in healthy subjects- a randomized clinical trial.

Posted on January 25, 2020 by David

Publication cover image “It has been hypothesized that besides its intraocular pressure (IOP) lowering potential, tetrahydrocannabinol (THC) may also improve ocular hemodynamics.

The aim of the present study was to investigate whether single oral administration of dronabinol, a synthetic THC, alters optic nerve head blood flow (ONHBF) and its regulation in healthy subjects.

The study was carried out in a randomized, placebo-controlled, double-masked, two-way crossover design in twenty-four healthy subjects. For each study participant, two study days were scheduled, on which they either received capsules containing 5mg dronabinol or placebo. ONHBF was measured with laser Doppler flowmetry at rest and while the study participants performed isometric exercise for six minutes to increase mean arterial blood pressure (MAP). This was repeated one hour after drug intake. Ocular perfusion pressure (OPP) was calculated as 2/3MAP-IOP.

Dronabinol was well tolerated and no cannabinoid-related psychoactive effects were reported.

Neither administration of dronabinol nor placebo had an effect on IOP, MAP or OPP. In contrast, dronabinol significantly increased ONHBF at rest by 9.5±8.1% whereas placebo did not show a change in ONHBF (0.3±7.4% vs. baseline, p<0.001 between study days). Dronabinol did not alter the autoregulatory response of ONHBF to isometric exercise.

In conclusion, the present data indicate that low dose dronabinol increases ONHBF in healthy subjects without affecting IOP, OPP or inducing psychoactive side effects. In addition, dronabinol does not alter the autoregulatory response of ONHBF to an experimental increase in OPP. Further studies are needed to investigate whether this effect can also be observed in glaucoma patients.”

https://www.ncbi.nlm.nih.gov/pubmed/31977076

https://ascpt.onlinelibrary.wiley.com/doi/abs/10.1002/cpt.1797

Crosstalk between the M1 muscarinic acetylcholine receptor and the endocannabinoid system: A relevance for Alzheimer’s disease?

Posted on January 25, 2020 by David

Cellular Signalling “Alzheimer’s disease (AD) is a neurodegenerative disorder which accounts for 60-70% of the 50 million worldwide cases of dementia and is characterised by cognitive impairments, many of which have long been associated with dysfunction of the cholinergic system.

Although the M₁ muscarinic acetylcholine receptor (mAChR) is considered a promising drug target for AD, ligands targeting this receptor have so far been unsuccessful in clinical trials.

As modulatory receptors to cholinergic transmission, the endocannabinoid system may be a promising drug target to allow fine tuning of the cholinergic system. Furthermore, disease-related changes have been found in the endocannabinoid system during AD progression and indeed targeting the endocannabinoid system at specific disease stages alleviates cognitive symptoms in numerous mouse models of AD.

Here we review the role of the endocannabinoid system in AD, and its crosstalk with mAChRs as a potential drug target for cholinergic dysfunction.”

https://www.ncbi.nlm.nih.gov/pubmed/31978506

“Targeting the endocannabinoid system could fine tune the cholinergic system”

https://www.sciencedirect.com/science/article/abs/pii/S089865682030022X?via%3Dihub

Cannabis use and outcomes after aneurysmal subarachnoid hemorrhage: A nationwide retrospective cohort study.

Posted on January 25, 2020 by David

Journal of Clinical Neuroscience Home “Cannabis is the most consumed recreational drug in the world.

It is possible that cannabis has an association with an increased risk of vasospasm-related strokes and delayed cerebral ischemia (DCI), which are major causes of morbidity and mortality in aneurysmal subarachnoid hemorrhage (aSAH). Hence, this study aimed to explore the independent relationship between cannabis use and outcomes after aSAH using the 2016 United States Nationwide Inpatient Sample.

RESULTS:

There were 42,394 patients identified with aSAH, of whom 925 were identified as cannabis users.

Cannabis users and non-users were similar in terms of severity of aSAH.

Although the unadjusted mortality rate was lower among cannabis users (16%) than non-users (22%), (p = 0.04), both the age-adjusted odds ratio (OR) (0.83, 95% confidence interval (CI): 0.56; 1.24) and the multivariate-adjusted OR (0.87, 95% CI: 0.54; 1.42) did not reach statistical significance.

Secondary outcomes did not reach statistical significance.

CONCLUSION:

In this nationwide cohort, cannabis users with aSAH had similar outcomes compared to nonusers. However, these results are likely limited by underreporting of cannabis use. Future prospective studies are needed to elucidate the pathophysiology and association between cannabis and outcomes following aSAH.”

https://www.ncbi.nlm.nih.gov/pubmed/31973920

https://www.jocn-journal.com/article/S0967-5868(19)31930-7/fulltext

The nephrologist’s guide to cannabis and cannabinoids.

Posted on January 25, 2020 by David

“Cannabis (marijuana, weed, pot, ganja, Mary Jane) is the most commonly used federally illicit drug in the United States.

The present review provides an overview of cannabis and cannabinoids with relevance to the practice of nephrology so that clinicians can best take care of patients.

RECENT FINDINGS:

Cannabis may have medicinal benefits for treating symptoms of advanced chronic kidney disease (CKD) and end-stage renal disease including as a pain adjuvant potentially reducing the need for opioids.

Cannabis does not seem to affect kidney function in healthy individuals. However, renal function should be closely monitored in those with CKD, the lowest effective dose should be used, and smoking should be avoided. Cannabis use may delay transplant candidate listing or contribute to ineligibility.

Cannabidiol (CBD) has recently exploded in popularity. Although generally well tolerated, safe without significant side effects, and effective for a variety of neurological and psychiatric conditions, consumers have easy access to a wide range of unregulated CBD products, some with inaccurate labeling and false health claims. Importantly, CBD may raise tacrolimus levels.

SUMMARY:

Patients and healthcare professionals have little guidance or evidence regarding the impact of cannabis use on people with kidney disease. This knowledge gap will remain as long as federal regulations remain prohibitively restrictive towards prospective research.”

https://www.ncbi.nlm.nih.gov/pubmed/31972598

https://journals.lww.com/co-nephrolhypertens/Abstract/publishahead/The_nephrologist_s_guide_to_cannabis_and.99088.aspx

A Review on Studies of Marijuana for Alzheimer’s Disease – Focusing on CBD, THC.

Posted on January 25, 2020 by David

book “This study was to discuss the research trend of dementia treatment using cannabis for the purpose of providing the basis of cannabis use for medical purposes in the future.

RESULTS:

These results implied that the CBD components of cannabis might be useful to treat and prevent AD because CBD components could suppress the main causal factors of AD.

Moreover, it was suggested that using CBD and THC together could be more useful than using CBD or THC alone.

CONCLUSION:

We hope that there will be a solid foundation to use cannabis for medical use by continuously evaluating the possibility of using cannabis for clinical purposes as a dementia treatment substance and cannabis can be used as a positive tool.”

https://www.ncbi.nlm.nih.gov/pubmed/31970019

“The ideal treatment for Alzheimer’s disease (AD) should be able to modulate the disease through multiple mechanisms rather than targeting a single dysregulated pathway.” http://www.ncbi.nlm.nih.gov/pubmed/25147120

“THC could be a potential therapeutic treatment option for Alzheimer’s disease through multiple functions and pathways.” http://www.ncbi.nlm.nih.gov/pubmed/25024327

“CBD treatment would be in line with preventative, multimodal drug strategies targeting a combination of pathological symptoms, which might be ideal for AD #therapy.” http://www.ncbi.nlm.nih.gov/pubmed/27471947

“Combination of THC and CBD exhibits a better therapeutic profile than each cannabis component alone and support the consideration of a cannabis-based medicine as potential therapy against AD.” http://www.ncbi.nlm.nih.gov/pubmed/25125475

http://www.thctotalhealthcare.com/category/alzheimers-disease-ad/

Cannabis use in pediatric cancer patients: what are they reading? A review of the online literature.

Posted on January 22, 2020 by David

“Recent changes to the legal status of marijuana in Canada warrant a review of the information that patients and families are accessing online regarding the role of cannabis in cancer.

The aims of the current research were to identify the quality of literature available online as well as the themes, and opinion (i.e., pro-, neutral, or anti-cannabis) of online articles.

RESULTS:

We found most articles were authored by journalists (39.4%) and MDs (14.1%) and published as news (35.2%) or web articles (28.2%). The content of articles focused on four themes: the reasons for and against cannabis use; the opinions of health care providers; the restrictions placed by governing bodies and the need for additional research, education, and standardization. Article opinions were neutral-pro-cannabis.

CONCLUSIONS:

Health care providers should be aware that the overall quality of information found online is considered “satisfactory.” The majority of articles present a pro-cannabis opinion.”

https://www.ncbi.nlm.nih.gov/pubmed/31960125

https://link.springer.com/article/10.1007%2Fs00520-020-05306-2