The endocannabinoid signaling system in cancer

Image result for trends in pharmacological sciences“Changes in lipid metabolism are intimately related to cancer. Several classes of bioactive lipids play roles in the regulation of signaling pathways involved in neoplastic transformation and tumor growth and progression.

The endocannabinoid system, comprising lipid-derived endocannabinoids, their G-protein-coupled receptors (GPCRs), and the enzymes for their metabolism, is emerging as a promising therapeutic target in cancer.

This report highlights the main signaling pathways for the antitumor effects of the endocannabinoid system in cancer and its basic role in cancer pathogenesis, and discusses the alternative view of cannabinoid receptors as tumor promoters.

We focus on new players in the antitumor action of the endocannabinoid system and on emerging crosstalk among cannabinoid receptors and other membrane or nuclear receptors involved in cancer. We also discuss the enzyme MAGL, a key player in endocannabinoid metabolism that was recently recognized as a marker of tumor lipogenic phenotype.”

https://www.cell.com/trends/pharmacological-sciences/fulltext/S0165-6147(13)00044-8?_returnURL=https%3A%2F%2Flinkinghub.elsevier.com%2Fretrieve%2Fpii%2FS0165614713000448%3Fshowall%3Dtrue

Cannabinoid receptor agonists reduce the short-term mitochondrial dysfunction and oxidative stress linked to excitotoxicity in the rat brain.

Neuroscience

“The endocannabinoid system (ECS) is involved in a considerable number of physiological processes in the Central Nervous System.

Recently, a modulatory role of cannabinoid receptors (CBr) and CBr agonists on the reduction of the N-methyl-d-aspartate receptor (NMDAr) activation has been demonstrated. Quinolinic acid (QUIN), an endogenous analog of glutamate and excitotoxic metabolite produced in the kynurenine pathway (KP), selectively activates NMDAr and has been shown to participate in different neurodegenerative disorders.

Since the early pattern of toxicity exerted by this metabolite is relevant to explain the extent of damage that it can produce in the brain, in this work we investigated the effects of the synthetic CBr agonist WIN 55,212-2 (WIN) and other agonists (anandamide or AEA, and CP 55,940 or CP) on early markers of QUIN-induced toxicity in rat striatal cultured cells and rat brain synaptosomes.

WIN, AEA and CP exerted protective effects on the QUIN-induced loss of cell viability. WIN also preserved the immunofluorescent signals for neurons and CBr labeling that were decreased by QUIN. The QUIN-induced early mitochondrial dysfunction, lipid peroxidation and reactive oxygen species (ROS) formation were also partially or completely prevented by WIN pretreatment, but not when this CBr agonist was added simultaneously with QUIN to brain synaptosomes.

These findings support a neuroprotective and modulatory role of cannabinoids in the early toxic events elicited by agents inducing excitotoxic processes.”

https://www.ncbi.nlm.nih.gov/pubmed/25446347

https://www.sciencedirect.com/science/article/abs/pii/S0306452214009737?via%3Dihub

The Endocannabinoid System and Oligodendrocytes in Health and Disease.

 Image result for frontiers in neuroscience“Cannabinoid-based interventions are being explored for central nervous system (CNS) pathologies such as neurodegeneration, demyelination, epilepsy, stroke, and trauma. As these disease states involve dysregulation of myelin integrity and/or remyelination, it is important to consider effects of the endocannabinoid system on oligodendrocytes and their precursors. In this review, we examine research reports on the effects of the endocannabinoid system (ECS) components on oligodendrocytes and their precursors, with a focus on therapeutic implications. Cannabinoid ligands and modulators of the endocannabinoid system promote cell signaling in oligodendrocyte precursor survival, proliferation, migration and differentiation, and mature oligodendrocyte survival and myelination. Agonist stimulation of oligodendrocyte precursor cells (OPCs) at both CB1 and CB2 receptors counter apoptotic processes via Akt/PI3K, and promote proliferation via Akt/mTOR and ERK pathways. CB1 receptors in radial glia promote proliferation and conversion to progenitors fated to become oligodendroglia, whereas CB2 receptors promote OPC migration in neonatal development. OPCs produce 2-arachidonoylglycerol (2-AG), stimulating cannabinoid receptor-mediated ERK pathways responsible for differentiation to arborized, myelin basic protein (MBP)-producing oligodendrocytes. In cell culture models of excitotoxicity, increased reactive oxygen species, and depolarization-dependent calcium influx, CB1 agonists improved viability of oligodendrocytes. In transient and permanent middle cerebral artery occlusion models of anoxic stroke, WIN55212-2 increased OPC proliferation and maturation to oligodendroglia, thereby reducing cerebral tissue damage. In several models of rodent encephalomyelitis, chronic treatment with cannabinoid agonists ameliorated the damage by promoting OPC survival and oligodendrocyte function. Pharmacotherapeutic strategies based upon ECS and oligodendrocyte production and survival should be considered.”

https://www.ncbi.nlm.nih.gov/pubmed/30416422

https://www.frontiersin.org/articles/10.3389/fnins.2018.00733/full

Cannabigerol Action at Cannabinoid CB1 and CB2 Receptors and at CB1-CB2 Heteroreceptor Complexes.

Image result for frontiers in pharmacology

“Cannabigerol (CBG) is one of the major phytocannabinoids present in Cannabis sativa L. that is attracting pharmacological interest because it is non-psychotropic and is abundant in some industrial hemp varieties.

The aim of this work was to investigate in parallel the binding properties of CBG to cannabinoid CB1 (CB1R) and CB2 (CB2R) receptors and the effects of the compound on agonist activation of those receptors and of CB1-CB2 heteroreceptor complexes.

The results indicate that CBG is indeed effective as regulator of endocannabinoid signaling.”

https://www.ncbi.nlm.nih.gov/pubmed/29977202

https://www.frontiersin.org/articles/10.3389/fphar.2018.00632/full

Anti-inflammatory Properties of Cannabidiol, a Nonpsychotropic Cannabinoid, in Experimental Allergic Contact Dermatitis.

Journal of Pharmacology and Experimental Therapeutics

“Phytocannabinoids modulate inflammatory responses by regulating the production of cytokines in several experimental models of inflammation.

Cannabinoid type-2 (CB2) receptor activation was shown to reduce the production of the monocyte chemotactic protein-2 (MCP-2) chemokine in polyinosinic-polycytidylic acid [poly-(I:C)]-stimulated human keratinocyte (HaCaT) cells, an in vitro model of allergic contact dermatitis (ACD).

We investigated if nonpsychotropic cannabinoids, such as cannabidiol (CBD), produced similar effects in this experimental model of ACD.

We show that in poly-(I:C)-stimulated HaCaT cells, CBD elevates the levels of AEA and dose-dependently inhibits poly-(I:C)-induced release of MCP-2, interleukin-6 (IL-6), IL-8, and tumor necrosis factor-α in a manner reversed by CB2 and TRPV1 antagonists 6-iodopravadoline (AM630) and 5′-iodio-resiniferatoxin (I-RTX), respectively, with no cytotoxic effect.

This is the first demonstration of the anti-inflammatory properties of CBD in an experimental model of ACD.”

https://www.ncbi.nlm.nih.gov/pubmed/29632236

http://jpet.aspetjournals.org/content/365/3/652.long

New insights on atherosclerosis: A cross-talk between endocannabinoid systems with gut microbiota.

Logo of jctr

“The incidence of atherosclerosis is increasing rapidly all over the world. Inflammatory processes have outstanding role in coronary artery disease (CAD) etiology and other atherosclerosis manifestations. Recently attentions have been increased about gut microbiota in many fields of medicine especially in inflammatory diseases like atherosclerosis. Ineffectiveness in gut barrier functions and subsequent metabolic endotoxemia (caused by rise in plasma lipopolysaccharide levels) is associated with low-grade chronic inflammation i.e. a recognized feature of atherosclerosis. Furthermore, the role of trimethylamine-N-oxide (TMAO), a gut bacterial metabolite has been suggested in atherosclerosis development. On the other hand, the effectiveness of gut microbiota modulation that results in TMAO reduction has been investigated. Moreover, considerable evidence supports a role for the endocannabinoid system (ECS) in atherosclerosis pathology which affects gut microbiota, but their effects on atherosclerosis are controversial. Therefore, we presented some evidence about the relationship between gut microbiota and ECS in atherosclerosis. We also presented evidences that gut microbiota modulation by pre/probiotics can have significant influence on the ECS.

Even though there are many questions which have been unanswered, studies demonstrated that mucosal barrier function disruption and subsequent gut microbiota-derived endotoxemia could contribute to cardiometabolic diseases pathogenesis. As well, number of studies revealed that TMAO in systemic circulation can activate macrophages which lead to cholesterol accumulation and subsequent foam cells formation in atherosclerotic lesions. On the other hand, accumulating evidence proposes that ECS involved in many physiological processes that are related to maintenance of gut-barrier function and inflammation regulation. Hence, although present literature review provides beneficial evidence in support of crosstalk between ECS and gut microbiota, additional studies are needed to clarify whether gut microbiota modulation can alter ECS tone and inflammation levels or not.”

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6203867/

Efficacy and Safety of Cannabidiol in Epilepsy: A Systematic Review and Meta-Analysis.

 Image result for drugs journal“Approximately one-third of patients with epilepsy presents seizures despite adequate treatment. Hence, there is the need to search for new therapeutic options. Cannabidiol (CBD) is a major chemical component of the resin of Cannabis sativa plant, most commonly known as marijuana. The anti-seizure properties of CBD do not relate to the direct action on cannabinoid receptors, but are mediated by a multitude of mechanisms that include the agonist and antagonist effects on ionic channels, neurotransmitter transporters, and multiple 7-transmembrane receptors. In contrast to tetra-hydrocannabinol, CBD lacks psychoactive properties, does not produce euphoric or intrusive side effects, and is largely devoid of abuse liability.

OBJECTIVE:

The aim of the study was to estimate the efficacy and safety of CBD as adjunctive treatment in patients with epilepsy using meta-analytical techniques.

METHODS:

Randomized, placebo-controlled, single- or double-blinded add-on trials of oral CBD in patients with uncontrolled epilepsy were identified. Main outcomes included the percentage change and the proportion of patients with ≥ 50% reduction in monthly seizure frequency during the treatment period and the incidence of treatment withdrawal and adverse events (AEs).

RESULTS:

Four trials involving 550 patients with Lennox-Gastaut syndrome (LGS) and Dravet syndrome (DS) were included. The pooled average difference in change in seizure frequency during the treatment period resulted 19.5 [95% confidence interval (CI) 8.1-31.0; p = 0.001] percentage points between the CBD 10 mg and placebo groups and 19.9 (95% CI 11.8-28.1; p < 0.001) percentage points between the CBD 20 mg and placebo arms, in favor of CBD. The reduction in all-types seizure frequency by at least 50% occurred in 37.2% of the patients in the CBD 20 mg group and 21.2% of the placebo-treated participants [risk ratio (RR) 1.76, 95% CI 1.07-2.88; p = 0.025]. Across the trials, drug withdrawal for any reason occurred in 11.1% and 2.6% of participants receiving CBD and placebo, respectively (RR 3.54, 95% CI 1.55-8.12; p = 0.003) [Chi squared = 2.53, degrees of freedom (df) = 3, p = 0.506; I2 = 0.0%]. The RRs to discontinue treatment were 1.45 (95% CI 0.28-7.41; p = 0.657) and 4.20 (95% CI 1.82-9.68; p = 0.001) for CBD at the doses of 10 and 20 mg/kg/day, respectively, in comparison to placebo. Treatment was discontinued due to AEs in 8.9% and 1.8% of patients in the active and control arms, respectively (RR 5.59, 95% CI 1.87-16.73; p = 0.002). The corresponding RRs for CBD at the doses of 10 and 20 mg/kg/day were 1.66 (95% CI 0.22-12.86; p = 0.626) and 6.89 (95% CI 2.28-20.80; p = 0.001). AEs occurred in 87.9% and 72.2% of patients treated with CBD and placebo (RR 1.22, 95% CI 1.11-1.33; p < 0.001). AEs significantly associated with CBD were somnolence, decreased appetite, diarrhea, and increased serum aminotransferases.

CONCLUSIONS:

Adjunctive CBD in patients with LGS or DS experiencing seizures uncontrolled by concomitant anti-epileptic treatment regimens is associated with a greater reduction in seizure frequency and a higher rate of AEs than placebo.”

https://www.ncbi.nlm.nih.gov/pubmed/30390221

Medical Use of Cannabinoids.

“Cannabinoid receptors, endocannabinoids and the enzymes responsible for their biosynthesis and degradation constitute the endocannabinoid system. In recent decades, the endocannabinoid system has attracted considerable interest as a potential therapeutic target in numerous pathological conditions. Its involvement in several physiological processes is well known, such as in energy balance, appetite stimulation, blood pressure, pain modulation, embryogenesis, nausea and vomiting control, memory, learning and immune response, among others, as well as in pathological conditions where it exerts a protective role in the development of certain disorders. As a result, it has been reported that changes in endocannabinoid levels may be related to neurological diseases such as Parkinson’s disease, Huntington’s disease, Alzheimer’s disease and multiple sclerosis, as well as anorexia and irritable bowel syndrome. Alterations in the endocannabinoid system have also been associated with cancer, affecting the growth, migration and invasion of some tumours. Cannabinoids have been tested in several cancer types, including brain, breast and prostate cancers. Cannabinoids have shown promise as analgesics for the treatment of both inflammatory and neuropathic pain. There is also evidence for a role of the endocannabinoid system in the control of emotional states, and cannabinoids could prove useful in decreasing and palliating post-traumatic stress disorder symptoms and anxiolytic disorders. The role of the endocannabinoid system in addictions has also been examined, and cannabinoids have been postulated as alternative and co-adjuvant treatments in some abuse syndromes, mainly in ethanol and opioid abuses. The expression of the endocannabinoid system in the eye suggests that it could be a potential therapeutic target for eye diseases. Considering the importance of the endocannabinoid system and the therapeutic potential of cannabinoids in this vast number of medical conditions, several clinical studies with cannabinoid-based medications are ongoing. In addition, some cannabinoid-based medications have already been approved in various countries, including nabilone and dronabinol capsules for the treatment of nausea and vomiting associated with chemotherapy, dronabinol capsules for anorexia, an oral solution of dronabinol for both vomiting associated with chemotherapy and anorexia, a Δ9-tetrahydrocannabinol/cannabidiol oromucosal spray for pain related to cancer and for spasticity and pain associated with multiple sclerosis, and an oral solution of cannabidiol for Dravet and Lennox-Gastaut syndromes. Here, we review the available efficacy, safety and tolerability data for cannabinoids in a range of medical conditions.”

https://www.ncbi.nlm.nih.gov/pubmed/30374797

https://link.springer.com/article/10.1007%2Fs40265-018-0996-1

Acute administration of beta-caryophyllene prevents endocannabinoid system activation during transient common carotid artery occlusion and reperfusion.

Image result for lipids in health and disease

“The transient global cerebral hypoperfusion/reperfusion achieved by induction of Bilateral Common Carotid Artery Occlusion followed by Reperfusion (BCCAO/R) has been shown to stimulate early molecular changes that can be easily traced in brain tissue and plasma, and that are indicative of the tissue physiological response to the reperfusion-induced oxidative stress and inflammation.

The aim of the present study is to probe the possibility to prevent the molecular changes induced by the BCCAO/R with dietary natural compounds known to possess anti-inflammatory activity, such as the phytocannabinoid beta-caryophyllene (BCP).

CONCLUSIONS:

Collectively, the pre-treatment with BCP, likely acting as agonist for CB2 and PPAR-alpha receptors, modulates in a beneficial way the ECS activation and the lipoperoxidation, taken as indicative of oxidative stress. Furthermore, our results support the evidence that BCP may be used as a dietary supplement to control the physiological response to the hypoperfusion/reperfusion-induced oxidative stress.”

“beta-caryophyllene (BCP), a sesquiterpene found as a common constituent of the essential oils of numerous food plants and primary component in Cannabis sativa L., is a dietary phytocannabinoid acting as selective agonist for CB2 receptor and peroxisome-proliferator activating receptor alpha (PPAR-alpha)”
“β-caryophyllene (BCP) is a common constitute of the essential oils of numerous spice, food plants and major component in Cannabis.”   http://www.ncbi.nlm.nih.gov/pubmed/23138934

Beta-caryophyllene protects diet-induced dyslipidemia and vascular inflammation in rats: Involvement of CB2 and PPAR-γ receptors.

Chemico-Biological Interactions

“Beta-caryophyllene (BCP) is a phytocannabinoid possessing selective agonistic activity to cannabinoid type-2 receptors (CB2R) and peroxisome proliferator-activated receptors-α (PPAR-α). However, few studies reported the contribution of PPAR-γ receptors in BCP effects.

The aim of this study was to investigate the BCP effects on diet-induced dyslipidemia and vascular inflammation as well as the involvement of CB2R and PPAR-γ receptors.

BCP treatment was superior to pioglitazone in anti-inflammatory and anti-atherosclerotic measures. BCP may represent a more potent alternate to pioglitazone avoiding its side effects in the treatment of insulin resistance and vascular inflammation.”

https://www.ncbi.nlm.nih.gov/pubmed/30343038

https://www.sciencedirect.com/science/article/pii/S0009279718309347?via%3Dihub

“β-caryophyllene (BCP) is a common constitute of the essential oils of numerous spice, food plants and major component in Cannabis.”   http://www.ncbi.nlm.nih.gov/pubmed/23138934