The effects of cannabidiol on the antigen-induced contraction of airways smooth muscle in the guinea-pig

The Role of Cannabinoid-1 Receptor Ligands in the Ovalbumin-Induced Mouse Model of Allergic Asthma: Is It Related to Transient Receptor Potential Vanilloid-1 Channels?

Objectives: The aim of this study was to investigate the role of cannabinoid (CB1) receptors on airway inflammation and hypersensitivity in allergic asthma and the potential interactions with TRPV1 channels. Materials and Methods: BALB/c mice were sensitized and provoked with ovalbumin to create a model of allergic asthma. CB1 selective agonist arachidonoyl 2'-chloroethylamide (ACEA) was administered intraperitoneally at doses of 0.5, 3, and 5 mg/kg. Receptor antagonism studies were performed utilizing selective CB1 antagonists AM251 at a dose of 3 mg/kg. TRPV1 channel was selectively blocked by capsazepine at a dose of 2.5 mg/kg. Penh values were recorded in vivo by a whole-body plethysmograph under methacholine challenge. Inflammatory cell count was performed in bronchoalveolar lavage fluid (BALF). Serum levels of proinflammatory cytokines were measured by Enzyme-Linked ImmunoSorbent Assay (ELISA). Inflammation in the lung tissue was scored histopathologically. Statistical significance was determined using one-way analysis of variance or Kruskal-Wallis test and expressed as p<0.05. Results: In sensitized animals, provocation with inhaled ovalbumin increased Penh values, serum interleukin (IL)-4, IL-5, IL-13 levels, eosinophil, neutrophil, lymphocyte, macrophage counts in BALF, and inflammation in the lung tissue. ACEA applications did not significantly alter Penh values, BALF inflammatory cell levels, and histological changes related to inflammation in the lung tissue according to the disease group; however, only at a dose of 5 mg/kg, it reduced the levels of the inflammatory cytokine IL-4. AM251 decreased Penh values, eosinophil and neutrophil migration in BALF, and inflammation score of lung tissue compared with the disease group. Although BALF inflammatory cell levels and Penh values were higher in the AM251+ACEA group than in the AM251 group, the differences were insignificant. In the CPZ+ACEA group, Penh values were significantly higher, and serum IL-4 and IL-13 levels and BALF eosinophil counts were lower than that in the CPZ group. Conclusions: This study demonstrated an important role of the CB1 receptors in allergic asthma. CB1 antagonism reduced airway hyperresponsiveness and inflammation and showed immunomodulatory effects. The effect of the CB1 agonist ACEA on asthma does not appear to be related to TRPV1 channels.

A Delightful Trip Along the Pathway of Cannabinoid and Endocannabinoid Chemistry and Pharmacology

After a traumatic childhood in Europe during the Second World War, I found that scientific research in Israel was a pleasure beyond my expectations. Over the last 65 year, I have worked on the chemistry and pharmacology of natural products. During the last few decades, most of my research has been on plant cannabinoids, the endogenous cannabinoids arachidonoyl ethanolamide (anandamide) and 2-arachidonoyl glycerol, and endogenous anandamide-like compounds, all of which are involved in a wide spectrum of physiological reactions. Two plant cannabinoids, Δ⁹-tetrahydrocannabinol and cannabidiol, are approved drugs. However, the endogenous cannabinoids and the anandamide-like constituents have not yet been well investigated in humans. For me, intellectual freedom-the ability to do research based on my own scientific interests-has been the most satisfying part of my working life. Looking back over the 91 years of my long life, I conclude that I have been lucky, very lucky, both personally and scientifically.

The endocannabinoid system and breathing

Recent changes in cannabis accessibility have provided adjunct therapies for patients across numerous disease states and highlights the urgency in understanding how cannabinoids and the endocannabinoid (EC) system interact with other physiological structures. The EC system plays a critical and modulatory role in respiratory homeostasis and pulmonary functionality. Respiratory control begins in the brainstem without peripheral input, and coordinates the preBötzinger complex, a component of the ventral respiratory group that interacts with the dorsal respiratory group to synchronize burstlet activity and drive inspiration. An additional rhythm generator: the retrotrapezoid nucleus/parafacial respiratory group drives active expiration during conditions of exercise or high CO₂. Combined with the feedback information from the periphery: through chemo- and baroreceptors including the carotid bodies, the cranial nerves, stretch of the diaphragm and intercostal muscles, lung tissue, and immune cells, and the cranial nerves, our respiratory system can fine tune motor outputs that ensure we have the oxygen necessary to survive and can expel the CO₂ waste we produce, and every aspect of this process can be influenced by the EC system. The expansion in cannabis access and potential therapeutic benefits, it is essential that investigations continue to uncover the underpinnings and mechanistic workings of the EC system. It is imperative to understand the impact cannabis, and exogenous cannabinoids have on these physiological systems, and how some of these compounds can mitigate respiratory depression when combined with opioids or other medicinal therapies. This review highlights the respiratory system from the perspective of central versus peripheral respiratory functionality and how these behaviors can be influenced by the EC system. This review will summarize the literature available on organic and synthetic cannabinoids in breathing and how that has shaped our understanding of the role of the EC system in respiratory homeostasis. Finally, we look at some potential future therapeutic applications the EC system has to offer for the treatment of respiratory diseases and a possible role in expanding the safety profile of opioid therapies while preventing future opioid overdose fatalities that result from respiratory arrest or persistent apnea.

Cannabidiol (CBD) Protects Adipose-Derived Mesenchymal Stem Cells (ASCs) against Endoplasmic Reticulum Stress Development and Its Complications

BACKGROUND

Recent studies suggested that individuals with metabolic disorders have altered function of adipocytes and adipose stem cell subpopulations, which impairs tissue homeostasis, promoting insulin resistance and diabetes development. The non-psychoactive phytocannabinoid CBD was found to modulate adipose tissue metabolism, however, its exact role in controlling ASCs' fate is still poorly understood.

OBJECTIVES

This investigation aimed to elucidate whether pretreatment of ASCs with CBD can protect against ER stress development and maintain the cytophysiological properties of cells.

METHODS

Human ASCs were cultured under control and adipogenic conditions. Prior to the experiments, cells in the experimental group were pretreated with CBD following the addition of an ER stress inducer-tunicamycin. After the experiments, the cells were subsequently tested for expression of the apoptotic, ER stress, and anti-inflammatory-related genes using RT-qPCR. Oxidative stress was analysed with flow cytometric assays.

RESULTS

Cells pretreated with CBD displayed decreased apoptosis and enhanced proliferation rate. Additionally, the expression of pro-inflammatory cytokines and miRNAs was significantly reduced. The obtained results also demonstrated an obvious reduction in intracellular accumulated ROS and NO, as well as mitigated ER stress through the down-regulation of IRE-1, PERK, CHOP, and ATF6 transcripts upon CBD treatment.

CONCLUSION

The presented data provide the evidence that CBD protects ASCs against ER stress development and its complications and, thus, offers new insights for the management of obesity through the regulation of adipose tissue dynamics.

Endocannabinoid metabolism inhibition ameliorates ovalbumin-induced allergic airway inflammation and hyperreactivity in Guinea pigs

AIMS

Endocannabinoids are biologically active cannabinoid-related substances endogenously synthesized in many mammalian tissues. Mainly two enzymes carry out their degradation; Fatty Acid Amide Hydrolase (FAAH) and Monoacylglycerol Lipase (MAGL). Endocannabinoids are shown to affect the modulation of inflammatory processes and airway responsiveness. In the present study, we investigated the effects of FAAH and MAGL inhibitor treatments in experimental allergic airway inflammation in guinea pigs.

MATERIALS AND METHODS

Guinea pigs were sensitized and challenged by ovalbumin to induce an allergic asthma model. Then, the effects of FAAH inhibitor URB597, MAGL inhibitor JZL184, and dual (FAAH/MAGL) inhibitor JZL195 on airway inflammation and hyperreactivity were evaluated.

KEY FINDINGS

Ovalbumin challenge increased airway reactivity, IgE in serum, IL-4, and IL-13, and the percentage of eosinophils in bronchoalveolar lavage (BAL). In addition, inhibition of FAAH or MAGL enzymes leads to an increase in endocannabinoid levels. The selective inhibition of the FAAH enzyme prevented inflammation indicators such as cytokine production and inflammatory cell infiltration but had a negligible effect on airway hyperreactivity. However, the inhibition of the MAGL enzyme or dual inhibition of both FAAH and MAGL enzymes tent to moderate both pulmonary inflammation and airway hyperreactivity.

SIGNIFICANCE

We have previously demonstrated that modulation of endocannabinoid levels in the airways by FAAH or MAGL inhibition can be useful in preventing acute lung inflammation. The results of the present study further suggest that FAAH and MAGL inhibitor treatment can also be a promising strategy for bronchial hyperreactivity and airway inflammation in allergic asthma.

Potential Neuroprotective Effect of Cannabinoids in Covid-19 Patients

The global pandemic caused by the SARS-CoV-2 virus began in early 2020 and is still present. The respiratory symptoms caused by COVID-19 are well established, however, neurological manifestations that may result from direct or indirect neurological damage after SARS-CoV-2 infection have been reported frequently. The main proposed pathophysiological processes leading to neurological damage in COVID-19 are cerebrovascular disease, and indirect mechanisms of inflammatory / autoimmune origin. A growing number of studies confirm that neuroprotective measures should be maintained in COVID-19 patients. On the other hand, cannabinoids have been the subject of various studies that propose them as potential promising drugs in chronic neurodegenerative diseases due to their powerful neuroprotective potential. In this review we address the possible mechanism of action of cannabinoids as a neuroprotective treatment in patients infected by SARS-CoV-2. The endocannabinoid system is found in multiple systems within the body, including the immune system. Its activation can lead to beneficial results, such as a decrease in viral entry, a decrease in viral replication, and a decrease in pro-inflammatory cytokines such as IL-2, IL-4, IL-6, IL-12, TNF-α or IFN-c through CB2R expression induced during inflammation by SARS-CoV-2 infection in the central nervous system.

The anti-inflammatory effects of cannabidiol and cannabigerol alone, and in combination

INTRODUCTION/BACKGROUND AND PURPOSE

Studies with Cannabis Sativa plant extracts and endogenous agonists of cannabinoid receptors have demonstrated anti-inflammatory, bronchodilator, and antitussive properties in the airways of allergic and non-allergic animals. However, the potential therapeutic use of cannabis and cannabinoids for the treatment of respiratory diseases has not been widely investigated, in part because of local irritation of airways by needing to smoke the cannabis, poor bioavailability when administered orally due to the lipophilic nature of cannabinoids, and the psychoactive effects of Δ9-Tetrahydrocannabinol (Δ9-THC) found in cannabis. The primary purpose of this study was to investigate the anti-inflammatory effects of two of the non-psychotropic cannabinoids, cannabidiol (CBD) and cannabigerol (CBG) alone and in combination, in a model of pulmonary inflammation induced by bacterial lipopolysaccharide (LPS). The second purpose was to explore the effects of two different cannabinoid formulations administered orally (PO) and intraperitoneally (IP). Medium-chain triglyceride (MCT) oil was used as the sole solvent for one formulation, whereas the second formulation consisted of a Cremophor® EL (polyoxyl 35 castor oil, CrEL)-based micellar solution.

RESULTS

Exposure of guinea pigs to LPS induced a 97 ± 7% and 98 ± 3% increase in neutrophils found in bronchoalveolar lavage fluid (BAL) at 4 h and 24 h, respectively. Administration of CBD and CBG formulated with MCT oil did not show any significant effects on the LPS-induced neutrophilia measured in the BAL fluid when compared with the vehicle-treated groups. Conversely, the administration of either cannabinoid formulated with CrEL induced a significant attenuation of the LPS induced recruitment of neutrophils into the lung following both intraperitoneal (IP) and oral (PO) administration routes, with a 55-65% and 50-55% decrease in neutrophil cell recruitment with the highest doses of CBD and CBG respectively. A combination of CBD and CBG (CBD:CBG = 1:1) formulated in CrEL and administered orally was also tested to determine possible interactions between the cannabinoids. However, a mixture of CBD and CBG did not show a significant change in LPS-induced neutrophilia. Surfactants, such as CrEL, improves the dissolution of lipophilic drugs in an aqueous medium by forming micelles and entrapping the drug molecules within them, consequently increasing the drug dissolution rate. Additionally, surfactants increase permeability and absorption by disrupting the structural organisation of the cellular lipid bilayer.

CONCLUSION

In conclusion, this study has provided evidence that CBD and CBG formulated appropriately exhibit anti-inflammatory activity. Our observations suggest that these non-psychoactive cannabinoids may have beneficial effects in treating diseases characterised by airway inflammation.

Immunomodulation by cannabinoids: Current uses, mechanisms, and identification of data gaps to be addressed for additional therapeutic application

The endocannabinoid system plays a critical role in immunity and therefore its components, including cannabinoid receptors 1 and 2 (CB₁ and CB₂), are putative druggable targets for immune-mediated diseases. Whether modulating endogenous cannabinoid levels or interacting with CB₁ or CB₂ receptors directly, cannabinoids or cannabinoid-based therapeutics (CBTs) show promise as anti-inflammatory or immune suppressive agents. Herein we provide an overview of cannabinoid effects in animals and humans that provide support for the use of CBTs in immune-mediated disease such as multiple sclerosis (MS), inflammatory bowel disease (IBD), asthma, arthritis, diabetes, human immunodeficiency virus (HIV), and HIV-associated neurocognitive disorder (HAND). This is not an exhaustive review of cannabinoid effects on immune responses, but rather provides: (1) key studies in which initial and/or novel observations were made in animal studies; (2) critical human studies including meta-analyses and randomized clinical trials (RCTs) in which CBTs have been assessed; and (3) evidence for the role of CB₁ or CB₂ receptors in immune-mediated diseases through genetic analyses of single nucleotide polymorphisms (SNPs) in the CNR1 and CNR2 genes that encode CB₁ or CB₂ receptors, respectively. Perhaps most importantly, we provide our view of data gaps that exist, which if addressed, would allow for more rigorous evaluation of the efficacy and risk to benefit ratio of the use of cannabinoids and/or CBTs for immune-mediated diseases.

Opportunities, Challenges and Pitfalls of Using Cannabidiol as an Adjuvant Drug in COVID-19

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection may lead to coronavirus disease 2019 (COVID-19) which, in turn, may be associated with multiple organ dysfunction. In this review, we present advantages and disadvantages of cannabidiol (CBD), a non-intoxicating phytocannabinoid from the cannabis plant, as a potential agent for the treatment of COVID-19. CBD has been shown to downregulate proteins responsible for viral entry and to inhibit SARS-CoV-2 replication. Preclinical studies have demonstrated its effectiveness against diseases of the respiratory system as well as its cardioprotective, nephroprotective, hepatoprotective, neuroprotective and anti-convulsant properties, that is, effects that may be beneficial for COVID-19. Only the latter two properties have been demonstrated in clinical studies, which also revealed anxiolytic and antinociceptive effects of CBD (given alone or together with Δ9-tetrahydrocannabinol), which may be important for an adjuvant treatment to improve the quality of life in patients with COVID-19 and to limit post-traumatic stress symptoms. However, one should be aware of side effects of CBD (which are rarely serious), drug interactions (also extending to drugs acting against COVID-19) and the proper route of its administration (vaping may be dangerous). Clearly, further clinical studies are necessary to prove the suitability of CBD for the treatment of COVID-19.

Endocannabinoid System in the Airways

Cannabinoids and the mammalian endocannabinoid system is an important research area of interest and attracted many researchers because of their widespread biological effects. The significant immune-modulatory role of cannabinoids has suggested their therapeutic use in several inflammatory conditions. Airways are prone to environmental irritants and stimulants, and increased inflammation is an important process in most of the respiratory diseases. Therefore, the main strategies for treating airway diseases are suppression of inflammation and producing bronchodilation. The ability of cannabinoids to induce bronchodilation and modify inflammation indicates their importance for airway physiology and pathologies. In this review, the contribution of cannabinoids and the endocannabinoid system in the airways are discussed, and the existing data for their therapeutic use in airway diseases are presented.

Cannabidiol reduces lung injury induced by hypoxic-ischemic brain damage in newborn piglets

BackgroundBrain hypoxic-ischemic (HI) damage induces distant inflammatory lung damage in newborn pigs. We aimed to investigate the effects of cannabidiol (CBD) on lung damage in this scenario.MethodsNewborn piglets received intravenous vehicle, CBD, or CBD+WAY100635 (5-HT_1A receptor antagonist) after HI brain damage (carotid flow interruption and FiO₂ 0.10 for 30 min). Total lung compliance (TLC), oxygenation index (OI), and extravascular lung water content (EVLW) were monitored for 6 h. Histological damage, interleukin (IL)-1β concentration, and oxidative stress were assessed in brain and lung tissue. Total protein content was determined in bronchoalveolar lavage fluid (BALF).ResultsCBD prevented HI-induced deleterious effects on TLC and OI and reduced lung histological damage, modulating inflammation (decreased leukocyte infiltration and IL-1 concentration) and reducing protein content in BALF and EVLW. These effects were related to CBD-induced anti-inflammatory changes in the brain. HI did not increase oxidative stress in the lungs. In the lungs, WAY100635 blunted the beneficial effects of CBD on histological damage, IL-1 concentration, and EVLW.ConclusionsCBD reduced brain HI-induced distant lung damage, with 5-HT_1A receptor involvement in these effects. Whether the effects of CBD on the lungs were due to the anti-inflammatory effects on the brain or due to the direct effects on the lungs remains to be elucidated.

Self-medication of achalasia with cannabis, complicated by a cannabis use disorder

Achalasia is a rare esophagus motility disorder. Medical, endoscopic and surgical treatments are available, but all endorse high relapse rates. No data has been published to date reporting a therapeutic effect of cannabis use neither in achalasia nor on its influence on manometric measurements. We report the case of a patient diagnosed with achalasia. He could benefit from a large panel of therapeutic interventions, but none of them was effective over the time. He first used cannabis at age 20 and identified benefits regarding achalasia symptoms. He maintained regular moderate cannabis use for 9 years, with minimal digestive inconvenience. A manometry performed without cannabis premedication was realized at age 26 and still found a cardiospasm. Cannabis use could explain the gap between functional symptoms assessment and manometry measurement. Further investigations are warranted to explore a therapeutic effect of cannabis in achalasia and possible influence on outcome measurements.

Cannabis smoking and respiratory health: consideration of the literature

The respiratory health effects from tobacco smoking are well described. Cannabis smoke contains a similar profile of carcinogenic chemicals as tobacco smoke but is inhaled more deeply. Although cannabis smoke is known to contain similar harmful and carcinogenic substances to tobacco smoke, relatively little is understood regarding the respiratory health effects from cannabis smoking. There is a need to integrate research on cannabis and respiratory health effects so that gaps in the literature can be identified and the more consistent findings can be consolidated with the purpose of educating smokers and health service providers. This review focuses on several aspects of respiratory health and cannabis use (as well as concurrent cannabis and tobacco use) and provides an update to (i) the pathophysiology; (ii) general respiratory health including symptoms of chronic bronchitis; and (iii) lung cancer.

Cannabidiol enhances xenobiotic permeability through the human placental barrier by direct inhibition of breast cancer resistance protein: an ex vivo study

OBJECTIVE

Drugs of abuse affect pregnancy outcomes, however, the mechanisms in which cannabis exerts its effects are not well understood. The aim of this study was to examine the influence of short-term (1-2 hours) exposure to cannabidiol, a major phytocannabinoid, on human placental breast cancer resistance protein function.

STUDY DESIGN

The in vitro effect of short-term exposure to cannabidoil on breast cancer resistance protein in BeWo and Jar cells (MCF7/P-gp cells were used for comparison) was tested with mitoxantrone uptake, and nicardipine was used as positive control. The ex vivo perfused cotyledon system was used for testing the effect of cannabidoil on glyburide transport across the placenta. Glyburide (200 ng/mL) was introduced to maternal and fetal compartments through a recirculating 2 hour perfusion, and its transplacental transport was tested with (n = 8) or without (n = 8) cannabidoil.

RESULTS

(1) Cannabidoil inhibition of breast cancer resistance protein-dependent mitoxantrone efflux was concentration dependent and of a noncell type specific nature (P < .0001); (2) In the cotyledon perfusion assay, the administration of cannabidoil to the maternal perfusion media increased the female/male ratio of glyburide concentrations (1.3 ± 0.1 vs 0.8 ± 0.1 at 120 minutes of perfusion, P < .001).

CONCLUSION

(1) Placental breast cancer resistance protein function is inhibited following even a short-term exposure to cannabidoil; (2) the ex vivo perfusion assay emphasize this effect by increased placental penetration of glyburide to the fetal compartment; and (3) these findings suggest that marijuana consumption enhances placental barrier permeability to xenobiotics and could endanger the developing fetus. Thus, the safety of drugs that are breast cancer resistance protein substrates is questionable during cannabis consumption by pregnant women.

Cannabidiol changes P-gp and BCRP expression in trophoblast cell lines

Objectives. Marijuana is the most commonly used illicit drug during pregnancy. Due to high lipophilicity, cannabinoids can easily penetrate physiological barriers like the human placenta and jeopardize the developing fetus. We evaluated the impact of cannabidiol (CBD), a major non-psychoactive cannabinoid, on P-glycoprotein (P-gp) and Breast Cancer Resistance Protein (BCRP) expression, and P-gp function in a placental model, BeWo and Jar choriocarcinoma cell lines (using P-gp induced MCF7 cells (MCF7/P-gp) for comparison). Study design. Following the establishment of the basal expression of these transporters in the membrane fraction of all three cell lines, P-gp and BCRP protein and mRNA levels were determined following chronic (24-72 h) exposure to CBD, by Western Blot and qPCR. CBD impact on P-gp efflux function was examined by uptake of specific P-gp fluorescent substrates (calcein-AM, DiOC2(3) and rhodamine123(rh123)). Cyclosporine A (CsA) served as a positive control. Results. Chronic exposure to CBD resulted in significant changes in the protein and mRNA levels of both transporters. While P-gp was down-regulated, BCRP levels were up-regulated in the choriocarcinoma cell lines. CBD had a remarkably different influence on P-gp and BCRP expression in MCF7/P-gp cells, demonstrating that these are cell type specific effects. P-gp dependent efflux (of calcein, DiOC2(3) and rh123) was inhibited upon short-term exposure to CBD. Conclusions. Our study shows that CBD might alter P-gp and BCRP expression in the human placenta, and inhibit P-gp efflux function. We conclude that marijuana use during pregnancy may reduce placental protective functions and change its morphological and physiological characteristics.