Conversion of Cannabidiol (CBD) Into Psychotropic Cannabinoids Including Tetrahydrocannabinol (THC): A Controversy in the Scientific Literature

PubMed Overview “Cannabidiol (CBD) is a naturally occurring, non-psychotropic cannabinoid of the hemp plant Cannabis sativa L. and has been known to induce several physiological and pharmacological effects. While CBD is approved as a medicinal product subject to prescription, it is also widely sold over the counter (OTC) in the form of food supplements, cosmetics and electronic cigarette liquids. However, regulatory difficulties arise from its origin being a narcotic plant or its status as an unapproved novel food ingredient.

Regarding the consumer safety of these OTC products, the question whether or not CBD might be degraded into psychotropic cannabinoids, most prominently tetrahydrocannabinol (THC), under in vivo conditions initiated an ongoing scientific debate. This feature review aims to summarize the current knowledge of CBD degradation processes, specifically the results of in vitro and in vivo studies. Additionally, the literature on psychotropic effects of cannabinoids was carefully studied with a focus on the degradants and metabolites of CBD, but data were found to be sparse.

While the literature is contradictory, most studies suggest that CBD is not converted to psychotropic THC under in vivo conditions. Nevertheless, it is certain that CBD degrades to psychotropic products in acidic environments. Hence, the storage stability of commercial formulations requires more attention in the future.”

https://pubmed.ncbi.nlm.nih.gov/32503116/

 

Evaluation of Repeated or Acute Treatment With Cannabidiol (CBD), Cannabidiolic Acid (CBDA) or CBDA Methyl Ester (HU-580) on Nausea and/or Vomiting in Rats and Shrews

 SpringerLink“Rationale: When acutely administered intraperitoneally, the non-psychoactive cannabinoid cannabidiol (CBD), its acidic precursor cannabidiolic acid (CBDA) and a stable methyl ester of CBDA (HU-580) reduce lithium chloride (LiCl)-induced conditioned gaping in male rats (a selective preclinical model of acute nausea) via activation of the serotonin 1A (5-HT1A) receptor.

Objectives: To utilise these compounds to manage nausea in the clinic, we must determine if their effectiveness is maintained when injected subcutaneously (s.c) and when repeatedly administered. First, we compared the effectiveness of each of these compounds to reduce conditioned gaping following repeated (7-day) and acute (1-day) pretreatments and whether these anti-nausea effects were mediated by the 5-HT1A receptor. Next, we assessed whether the effectiveness of these compounds can be maintained when administered prior to each of 4 conditioning trials (once per week). We also evaluated the ability of repeated CBD (7 days) to reduce LiCl-induced vomiting in Suncus murinus. Finally, we examined whether acute CBD was equally effective in male and female rats.

Results: Both acute and repeated (7 day) s.c. administrations of CBD (5 mg/kg), CBDA (1 μg/kg) and HU-580 (1 μg/kg) similarly reduced LiCl-induced conditioned gaping, and these effects were blocked by 5HT1A receptor antagonism. When administered over 4 weekly conditioning trials, the anti-nausea effectiveness of each of these compounds was also maintained. Repeated CBD (5 mg/kg, s.c.) maintained its anti-emetic efficacy in S. murinus. Acute CBD (5 and 20 mg/kg, s.c.) administration reduced LiCl-induced conditioned gaping similarly in male and female rats.

Conclusion: When administered repeatedly (7 days), CBD, CBDA and HU-580 did not lose efficacy in reducing nausea and continued to act via agonism of the 5-HT1A receptor. When administered across 4 weekly conditioning trials, they maintained their effectiveness in reducing LiCl-induced nausea. Repeated CBD also reduced vomiting in shrews. Finally, CBD’s anti-nausea effects were similar in male and female rats. This suggests that these cannabinoids may be useful anti-nausea and anti-emetic treatments for chronic conditions, without the development of tolerance.”

https://pubmed.ncbi.nlm.nih.gov/32488349/

https://link.springer.com/article/10.1007%2Fs00213-020-05559-z

Cannabidiol Disrupts Conditioned Fear Expression and Cannabidiolic Acid Reduces Trauma-Induced Anxiety-Related Behaviour in Mice

Behavioural Pharmacology (journal) - Wikipedia“The major phytocannabinoid cannabidiol (CBD) has anxiolytic properties and lacks tetrahydrocannabinol-like psychoactivity. Cannabidiolic acid (CBDA) is the acidic precursor to CBD, and this compound appears more potent than CBD in animal models of emesis, pain and epilepsy. In this short report, we aimed to examine whether CBDA is more potent than CBD in disrupting expression of conditioned fear and generalised anxiety-related behaviour induced by Pavlovian fear conditioning. Mice underwent fear conditioning and 24 h later were administered CBD and CBDA before testing for fear expression and generalized anxiety-like behaviour. We found that CBD and CBDA had dissociable effects; while CBD but not CBDA disrupted cued fear memory expression, CBDA but not CBD normalized trauma-induced generalized anxiety-related behaviour. Neither phytocannabinoid affected contextual fear expression. Our findings form the basis for future experiments examining whether phytocannabinoids, alone and in combination, are effective in these mouse models of fear and anxiety.”

https://pubmed.ncbi.nlm.nih.gov/32483052/

https://journals.lww.com/behaviouralpharm/Abstract/9000/Cannabidiol_disrupts_conditioned_fear_expression.99176.aspx

A Pilot Randomised Placebo-Controlled Trial of Cannabidiol to Reduce Severe Behavioural Problems in Children and Adolescents With Intellectual Disability

 British Journal of Clinical Pharmacology“Introduction: Severe Behavioural Problems (SBP) are a major contributor to morbidity in children with Intellectual Disability (ID). Medications used to treat SBP in ID are associated with a high risk of side effects. Cannabidiol has potential therapeutic effects in SBP. This pilot study aimed to investigate the feasibility of conducting a randomized placebo-controlled trial of cannabidiol to reduce SBP in children with ID.

Methods: Double-blind, placebo-controlled, two-armed, parallel-design, randomised controlled trial of cannabidiol in children aged 8 – 16 years with ID and SBP. Participants were randomized 1:1 to receive either 98% cannabidiol in oil (Tilray, Canada) or placebo orally for 8 weeks. The dose was up-titrated over 9 days to 20mg/kg/day in two divided doses, with a maximum dose of 500mg twice/day. The feasibility and acceptability of all study components were assessed.

Results: Eight children were randomised, and all completed the full study protocol. There were no Serious Adverse Events or drop-outs. Protocol adherence for key study components was excellent: study visits 100%, medication adherence 100%, blood tests 92%, and questionnaire completion 88%. Parents reported a high degree of acceptability with the study design. All parents reported they would recommend the study to other families with children with similar problems. There was an efficacy signal in favour of active drug.

Conclusions: The findings suggest that the study protocol is feasible and acceptable to patients with ID and SBP and their families.”

https://pubmed.ncbi.nlm.nih.gov/32478863/

https://bpspubs.onlinelibrary.wiley.com/doi/abs/10.1111/bcp.14399

High Expression of Cannabinoid Receptor 2 on Cytokine-Induced Killer Cells and Multiple Myeloma Cells

ijms-logo“Multiple myeloma (MM) is characterized by aberrant bone marrow plasma cell (PC) proliferation and is one of the most common hematological malignancies. The potential effect of cannabinoids on the immune system and hematological malignancies has been poorly characterized.

Cannabidiol (CBD) may be used to treat various diseases. CBD is known to exert immunomodulatory effects through the activation of cannabinoid receptor 2 (CB2), which is expressed in high levels in the hematopoietic system.

Cytokine-induced killer (CIK) cells are a heterogeneous population of polyclonal T lymphocytes obtained via ex vivo sequential incubation of peripheral blood mononuclear cells (PBMCs) with interferon-γ (IFN-γ), anti CD3 monoclonal antibody, and IL-2. They are characterized by the expression of CD3+ and CD56+, which are surface markers common to T lymphocytes and natural killer (NK) cells. CIK cells are mainly used in hematological patients who suffer relapse after allogeneic transplantation.

Here, we investigated their antitumor effect in combination with pure cannabidiol in KMS-12 MM cells by lactate dehydrogenase LDH cytotoxicity assay, CCK-8 assay, and flow cytometry analysis. The surface and intracellular CB2 expressions on CIK cells and on KMS-12 and U-266 MM cell lines were also detected by flow cytometry.

Our findings confirm that the CB2 receptor is highly expressed on CIK cells as well as on MM cells. CBD was able to decrease the viability of tumor cells and can have a protective role for CIK cells. It also inhibits the cytotoxic activity of CIKs against MM at high concentrations, so in view of a clinical perspective, it has to be considered that the lower concentration of 1 µM can be used in combination with CIK cells. Further studies will be required to address the mechanism of CBD modulation of CIK cells in more detail.”

https://pubmed.ncbi.nlm.nih.gov/32471216/

https://www.mdpi.com/1422-0067/21/11/3800

Pharmacological Data of Cannabidiol- And Cannabigerol-Type Phytocannabinoids Acting on Cannabinoid CB 1, CB 2 and CB 1/CB 2 Heteromer Receptors

Pharmacological Research“Background: Recent approved medicines whose active principles are Δ9Tetrahidrocannabinol (Δ9-THC) and/or cannabidiol (CBD) open novel perspectives for other phytocannabinoids also present in Cannabis sativa L. varieties. Furthermore, solid data on the potential benefits of acidic and varinic phytocannabinoids in a variety of diseases are already available. Mode of action of cannabigerol (CBG), cannabidiolic acid (CBDA), cannabigerolic acid (CBGA), cannabidivarin (CBDV) and cannabigerivarin (CBGV) is, to the very least, partial.

Hypothesis/purpose: Cannabinoid CB1 or CB2 receptors, which belong to the G-protein-coupled receptor (GPCR) family, are important mediators of the action of those cannabinoids. Pure CBG, CBDA, CBGA, CBDV and CBGV from Cannabis sativa L. are differentially acting on CB1 or CB2 cannabinoid receptors.

Study design: Determination of the affinity of phytocannabinoids for cannabinoid receptors and functional assessment of effects promoted by these compounds when interacting with cannabinoid receptors.

Methods: A heterologous system expressing the human versions of CB1 and/or CB2 receptors was used. Binding to membranes was measured using radioligands and binding to living cells using a homogenous time resolved fluorescence resonance energy transfer (HTRF) assay. Four different functional outputs were assayed: determination of cAMP levels and of extracellular-signal-related-kinase phosphorylation, label-free dynamic mass redistribution (DMR) and ß-arrestin recruitment.

Results: Affinity of cannabinoids depend on the ligand of reference and may be different in membranes and in living cells. All tested phytocannabinoids have agonist-like behavior but behaved as inverse-agonists in the presence of selective receptor agonists. CBGV displayed enhanced potency in many of the functional outputs. However the most interesting result was a biased signaling that correlated with differential affinity, i.e. the overall results suggest that the binding mode of each ligand leads to specific receptor conformations underlying biased signaling outputs.

Conclusion: Results here reported and the recent elucidation of the three-dimensional structure of CB1 and CB2 receptors help understanding the mechanism of action that might be protective and the molecular drug-receptor interactions underlying biased signaling.”

https://pubmed.ncbi.nlm.nih.gov/32470563/

https://www.sciencedirect.com/science/article/abs/pii/S1043661820312482?via%3Dihub

Acute Inflammation and Pathogenesis of SARS-CoV-2 Infection: Cannabidiol as a Potential Anti-Inflammatory Treatment?

Cytokine & Growth Factor Reviews

“Cannabidiol to decrease SARS-CoV-2 associated inflammation.

Cannabidiol (CBD) is a phytocannabinoid with various clinical applications and has proven efficacy for certain medical conditions, along with a favorable safety and tolerability profile.

Cannabinoids can suppress immune activation and inflammatory cytokine production, suggesting their potential for tempering excessive inflammation.

Therefore, as SARS-CoV2 induces significant damage through pro-inflammatory cytokine storm mediated by macrophages and other immune cells and based on the fact that CBD has broad anti-inflammatory properties, CBD might represent as a potential anti-inflammatory therapeutic approach against SARS-CoV2-induced inflammation.

As CBD is already a therapeutic agent used in clinical medicine and has a favorable safety profile, the results of in vitro and animal model proof-of-concept studies would provide the necessary supporting evidence required before embarking on costly and labor-intensive clinical trials.”

https://pubmed.ncbi.nlm.nih.gov/32467020/

https://www.sciencedirect.com/science/article/pii/S1359610120301040?via%3Dihub

Cannabinomics: Application of Metabolomics in Cannabis ( Cannabis sativa L.) Research and Development

frontiers in plant science – Retraction Watch “Cannabis (Cannabis sativa L.) is a complex, polymorphic plant species, which produces a vast array of bioactive metabolites, the two major chemical groups being cannabinoids and terpenoids. Nonetheless, the psychoactive cannabinoid tetrahydrocannabinol (Δ 9 -THC) and the non-psychoactive cannabidiol (CBD), are the two major cannabinoids that have monopolized the research interest.

Currently, more than 600 Cannabis varieties are commercially available, providing access to a multitude of potent extracts with complex compositions, whose genetics are largely inconclusive. Recently introduced legislation on Cannabis cultivation in many countries represents a great opportunity, but at the same time, a great challenge for Cannabis research and development (R&D) toward applications in the pharmaceutical, food, cosmetics, and agrochemical industries.

Based on its versatility and unique capabilities in the deconvolution of the metabolite composition of complex matrices, metabolomics represents an ideal bioanalytical tool that could greatly assist and accelerate Cannabis R&D. Among others, Cannabis metabolomics or cannabinomics can be applied in the taxonomy of Cannabis varieties in chemovars, the research on the discovery and assessment of new Cannabis-based sources of bioactivity in medicine, the development of new food products, and the optimization of its cultivation, aiming for improvements in yield and potency.

Although Cannabis research is still in its infancy, it is highly foreseen that the employment of advanced metabolomics will provide insights that could assist the sector to face the aforementioned challenges. Within this context, here, the current state-of-the-art and conceptual aspects of cannabinomics are presented.”

https://pubmed.ncbi.nlm.nih.gov/32457786/

https://www.frontiersin.org/articles/10.3389/fpls.2020.00554/full

www.frontiersin.org

Effects of Chronic Cannabidiol Treatment in the Rat Chronic Unpredictable Mild Stress Model of Depression

biomolecules-logo“Several neuropharmacological actions of cannabidiol (CBD) due to the modulation of the endocannabinoid system as well as direct serotonergic and gamma-aminobutyric acidergic actions have recently been identified.

The current study aimed to reveal the effect of a long-term CBD treatment in the chronic unpredictable mild stress (CUMS) model of depression.

Adult male Wistar rats (n = 24) were exposed to various stressors on a daily basis in order to induce anhedonia and anxiety-like behaviors. CBD (10 mg/kg body weight) was administered by daily intraperitoneal injections for 28 days (n = 12). The effects of the treatment were assessed on body weight, sucrose preference, and exploratory and anxiety-related behavior in the open field (OF) and elevated plus maze (EPM) tests. Hair corticosterone was also assayed by liquid chromatography-mass spectrometry.

At the end of the experiment, CBD-treated rats showed a higher rate of body weight gain (5.94% vs. 0.67%) and sucrose preference compared to controls. A significant increase in vertical exploration and a trend of increase in distance traveled in the OF test were observed in the CBD-treated group compared to the vehicle-treated group. The EPM test did not reveal any differences between the groups. Hair corticosterone levels increased in the CBD-treated group, while they decreased in controls compared to baseline (+36.01% vs. -45.91%). In conclusion, CBD exerted a prohedonic effect in rats subjected to CUMS, demonstrated by the increased sucrose preference after three weeks of treatment.

The reversal of the effect of CUMS on hair corticosterone concentrations might also point toward an anxiolytic or antidepressant-like effect of CBD, but this needs further confirmation.”

https://pubmed.ncbi.nlm.nih.gov/32455953/

https://www.mdpi.com/2218-273X/10/5/801

Does Cannabidiol Have Antiseizure Activity Independent of Its Interactions With Clobazam? An Appraisal of the Evidence From Randomized Controlled Trials

 Epilepsia“Four pivotal randomized placebo-controlled trials have demonstrated that adjunctive therapy with cannabidiol (CBD) improves seizure control in patients with Dravet syndrome (DS) and Lennox-Gastaut syndrome (LGS).

Between 47% and 68% of patients allocated to CBD treatment in these trials were receiving clobazam (CLB), which shows complex interactions with CBD resulting, in particular, in a 3.4- to 5-fold increase in plasma concentration of the active metabolite norclobazam. This raises concern as to the role played by these interactions in determining the reduction in seizure frequency in CBD-treated patients, and the question of whether CBD per se has clinically evident antiseizure effects.

We appraised available evidence on the clinical consequences of the CBD-CLB interaction, focusing on subgroup analyses of seizure outcomes in patients on and off CLB comedication in the pivotal CBD trials, as provided by the European Medicines Agency Public Assessment Report.

Evaluation of the results of individual trials clearly showed that improvement in seizure control over placebo was greater when CBD was added on to CLB than when it was added on to other medications. However, seizure control was also improved in patients off CLB, and despite the small sample size the difference vs placebo was statistically significant for the 10 mg/kg/d dose in one of the two LGS trials.

Stronger evidence for an antiseizure effect of CBD independent of an interaction with CLB emerges from meta-analyses of seizure outcomes in the pooled population of LGS and DS patients not receiving CLB comedication.

Although these results need to be interpreted taking into account methodological limitations, they provide the best clinical evidence to date that CBD exerts therapeutic effects in patients with epilepsy that are independent of its interaction with CLB. Greater antiseizure effects, and a greater burden of adverse effects, are observed when CBD is combined with CLB.”

https://pubmed.ncbi.nlm.nih.gov/32452568/

https://onlinelibrary.wiley.com/doi/abs/10.1111/epi.16542