Cannabinoid Drugs Research Articles

Effects of repeated long-term psychosocial stress and acute cannabinoid exposure on mouse corticostriatal circuitries: Implications for neuropsychiatric disorders.

SummaryIntroductionVulnerability to psychiatric manifestations is achieved by the influence of genetic and environment including stress and cannabis consumption. Here, we used a psychosocial stress model based on resident‐intruder confrontations to study the brain corticostriatal‐function, since deregulation of corticostriatal circuitries has been reported in many psychiatric disorders. CB 1 receptors are widely expressed in the central nervous system and particularly, in both cortex and striatum brain structures.Aims and methodsThe investigation presented here is addressed to assess the impact of repeated stress following acute cannabinoid exposure on behavior and corticostriatal brain physiology by assessing mice behavior, the concentration of endocannabinoid and endocannabinoid‐like molecules and changes in the transcriptome.ResultsStressed animals urinated frequently; showed exacerbated scratching activity, lower striatal N‐arachidonylethanolamine (AEA) levels and higher cortical expression of cholinergic receptor nicotinic alpha 6. The cannabinoid agonist WIN55212.2 diminished locomotor activity while the inverse agonist increased the distance travelled in the center of the open field. Upon CB 1 activation, N‐oleoylethanolamide and N‐palmitoylethanolamide, two AEA congeners that do not interact directly with cannabinoid receptors, were enhanced in the striatum. The co‐administration with both cannabinoids induced an up‐regulation of striatal FK506 binding protein 5. The inverse agonist in controls reversed the effects of WIN55212.2 on motor activity. When Rimonabant was injected under stress, the cortical levels of 2‐arachidonoylglycerol were maximum. The agonist and the antagonist influenced the cortical expression of cholinergic receptor nicotinic alpha 6 and serotonin transporter neurotransmitter type 4 in opposite directions, while their co‐administration tended to produce a null effect under stress.ConclusionsThe endocannabinoid system had a direct effect on serotoninergic neurotransmission and glucocorticoid signaling. Cholinergic receptor nicotinic alpha‐6 was shown to be deregulated in response to stress and following synthetic cannabinoid drugs thus could confer vulnerability to cannabis addiction and psychosis. Targeting the receptors of endocannabinoids and endocannabinoid‐like mediators might be a valuable option for treating stress‐related neuropsychiatric symptoms.

Finding order in chemical chaos - Continuing characterization of synthetic cannabinoid receptor agonists

Diversion of synthetic cannabinoids from the lab to drugs of abuse has become increasingly prevalent in recent years. Moreover, as earlier synthetic cannabinoids were banned, manufacturers introduced a new supply of novel compounds to serve as replacements. Hence, the chemical diversity of synthetic cannabinoid analogs has also rapidly increased. The present study examined 8 new synthetic cannabinoids: AM-1220, AM-2232, AM-2233, AM-679, EAM-2201, JWH-210, JHW-251, and MAM-2201. Each compound was assessed for binding affinity and functional activation of CB1 and CB2 receptors, and pharmacological equivalence with Δ9-tetrahydrocannabinol (THC) in THC drug discrimination. All compounds bound to and activated CB1 and CB2 receptors, although efficacy at the CB2 receptor was reduced compared to that for the CB1 receptor. Similarly, all compounds stimulated [35S]GTPγS binding through the CB1 receptor, and all compounds except AM-1220 and AM-2233 stimulated [35S]GTPγS binding through the CB2 receptor. Furthermore, these compounds, along with CP55,940, substituted for THC in THC drug discrimination. Rank order of potency in drug discrimination was correlated with CB1 receptor binding affinity. Together, these results suggest that all test compounds share the THC-like subjective effects of marijuana. Interestingly, the most potent compounds in CB1 binding in the present study were also the compounds that have been found recently in the U.S., MAM-2201, EAM-2201, JWH-210, AM-2233, and AM-1220. These results indicate that the evolution of the synthetic cannabinoid drug market may be focused toward compounds with increased potency.This article is part of the Special Issue entitled ‘Designer Drugs and Legal Highs.’

Cannabidiol and palmitoylethanolamide are anti-inflammatory in the acutely inflamed human colon.

We sought to quantify the anti-inflammatory effects of two cannabinoid drugs, cannabidiol (CBD) and palmitoylethanolamide (PEA), in cultured cell lines and compared this effect with experimentally inflamed explant human colonic tissue. These effects were explored in acutely and chronically inflamed colon, using inflammatory bowel disease and appendicitis explants. Caco-2 cells and human colonic explants collected from elective bowel cancer, inflammatory bowel disease (IBD) or acute appendicitis resections, and were treated with the following drug treatments: vehicle, an inflammatory protocol of interferon γ (IFNγ) and tumour necrosis factor α (TNFα; 10 ng/ml), inflammation and PEA (10 µM), inflammation and CBD (10 µM), and PEA or CBD alone, CBD or vehicle were added simultaneously with IFNγ. Nine intracellular signalling phosphoproteins were determined by multiplex. Inflammatory cytokine secretion was determined using ELISA. Receptor mechanisms were investigated using antagonists for CB1, CB2, PPARα, PPARγ, TRPV1 and GPR55. IFNγ and TNFα treatment increased phosphoprotein and cytokine levels in Caco-2 cultures and colonic explants. Phosphoprotein levels were significantly reduced by PEA or CBD in Caco-2 cultures and colonic explants. CBD and PEA prevented increases in cytokine production in explant colon, but not in Caco-2 cells. CBD effects were blocked by the CB2 antagonist AM630 and TRPV1 antagonist SB366791. PEA effects were blocked by the PPARα antagonist GW6471. PEA and CBD were anti-inflammatory in IBD and appendicitis explants. PEA and CBD are anti-inflammatory in the human colon. This effect is not seen in cultured epithelial cells. Appropriately sized clinical trials should assess their efficacy.

Cannabinoids Modulate Neuronal Activity and Cancer by CB1 and CB2 Receptor-Independent Mechanisms.

Cannabinoids include the active constituents of Cannabis or are molecules that mimic the structure and/or function of these Cannabis-derived molecules. Cannabinoids produce many of their cellular and organ system effects by interacting with the well-characterized CB1 and CB2 receptors. However, it has become clear that not all effects of cannabinoid drugs are attributable to their interaction with CB1 and CB2 receptors. Evidence now demonstrates that cannabinoid agents produce effects by modulating activity of the entire array of cellular macromolecules targeted by other drug classes, including: other receptor types; ion channels; transporters; enzymes, and protein- and non-protein cellular structures. This review summarizes evidence for these interactions in the CNS and in cancer, and is organized according to the cellular targets involved. The CNS represents a well-studied area and cancer is emerging in terms of understanding mechanisms by which cannabinoids modulate their activity. Considering the CNS and cancer together allow identification of non-cannabinoid receptor targets that are shared and divergent in both systems. This comparative approach allows the identified targets to be compared and contrasted, suggesting potential new areas of investigation. It also provides insight into the diverse sources of efficacy employed by this interesting class of drugs. Obtaining a comprehensive understanding of the diverse mechanisms of cannabinoid action may lead to the design and development of therapeutic agents with greater efficacy and specificity for their cellular targets.

Human serum albumin: A modulator of cannabinoid drugs.

The endocannabinoid system is a unique neuromodulatory system that affects a wide range of biological processes and maintains the homeostasis in all mammal body systems. In recent years, several pharmacological tools to target endocannabinoid neurotransmission have been developed, including direct and indirect cannabinoid agonists and cannabinoid antagonists. Due to their hydrophobic nature, cannabinoid agonists and antagonists need to bind specific transporters to allow their distribution in body fluids. Human serum albumin (HSA), the most abundant plasma protein, is a key determinant of drug pharmacokinetics. As HSA binds both the endocannabinoid anandamide and the active ingredient of Cannabis sativa, Δ-9-tetrahydrocannabinol, we hypothesize that HSA can be the most important carrier of cannabinoid drugs. In silico docking observations strongly indicate that HSA avidly binds the indirect cannabinoid agonists URB597, AM5206, JZL184, JZL195, and AM404, the direct cannabinoid agonists WIN55,212-2 and CP55,940, and the prototypical cannabinoid antagonist/inverse agonist SR141716. Values of the free energy for cannabinoid drugs binding to HSA range between -5.4 kcal mol-1 and -10.9 kcal mol-1 . Accounting for the HSA concentration in vivo (∼ 7.5 × 10-4 M), values of the free energy here determined suggest that the formation of the HSA:cannabinoid drug complexes may occur in vivo. Therefore, HSA appears to be an important determinant for cannabinoid efficacy and may guide the choice of the drug dose regimen to optimize drug efficacy and to avoid drug-related toxicity. © 2017 IUBMB Life, 69(11):834-840, 2017.

Cannabinoid CB1 receptor inverse agonist MJ08 stimulates glucose production via hepatic sympathetic innervation in rats

As a key insulin target tissue for maintaining systemic glucose homeostasis, the liver plays important roles in improving obesity-associated insulin intolerance via selective cannabinoid CB1 receptor antagonism/inverse agonism. However, it is unclear whether this receptor inverse agonism affects hepatic glucose metabolism. MJ08 is a novel cannabinoid CB1 receptor antagonist/inverse agonist that has superior inverse agonism over the well-known antagonist/inverse agonist, SR141716 (rimonabant). MJ08 remarkably elevates fasting blood glucose independent of inhibition of insulin release in mice. In the current study, MJ08 was used to investigate the mechanism by which liver cannabinoid CB1 receptor inverse activation regulates hepatic glucose metabolism. MJ08 stimulated hepatic glucose production (HGP) in a dose-dependent manner and promoted gluconeogenic gene expression in perfused rat liver. SR141716 exhibited similar but weaker effects. The cannabinoid CB1 receptor agonist (WIN 55,212-2), Gs protein-cyclic AMP (cAMP)-dependent pathway inhibitors (NF449 and H89), β-adrenoceptor antagonist (propranolol), and peripheral sympathetic inhibitor (reserpine) could antagonize MJ08-induced HGP. Furthermore, MJ08 and SR141716 induced monoamine neurotransmitter (noradrenaline) release and increased cAMP content significantly in perfused liver, although only a slight increase was observed in primary cultured hepatocytes. These results indicate that local liver cannabinoid CB1 receptor inverse agonism via hepatic sympathetic innervation is responsible for the HGP induced by MJ08. Thus, high inverse agonistic activity could increase fasting blood glucose levels and should be avoided in the development of peripheral cannabinoid CB1 receptor-targeted weight-loss drugs.

Synthetic Cathinone and Cannabinoid Designer Drugs Pose a Major Risk for Public Health.

As part of an increasing worldwide use of designer drugs, recent use of compounds containing cathinones and synthetic cannabinoids is especially prevalent. Here, we reviewed current literature on the prevalence, epidemiology, bio-behavioral effects, and detection of these compounds. Gender differences and clinical effects will also be examined. Chronic use of synthetic cathinone compounds can have major effects on the central nervous system and can induce acute psychosis, hypomania, paranoid ideation, and delusions, similar to the effects of other better-known amphetamine-type stimulants. Synthetic cannabinoid products have effects that are somewhat similar to those of natural cannabis but more potent and long-lasting than THC. Some of these compounds are potent and dangerous, having been linked to psychosis, mania, and suicidal ideation. Novel compounds are developed rapidly and new screening techniques are needed to detect them as well as a rigorous regulation and legislation reinforcement to prevent their distribution and use. Given the rapid increase in the use of synthetic cathinones and cannabinoid designer drugs, their potential for dependence and abuse, and harmful medical and psychiatric effects, there is a need for research and education in the areas of prevention and treatment.

The great divide: Separation between in vitro and in vivo effects of PSNCBAM-based CB1 receptor allosteric modulators

While allosteric modulators of the cannabinoid type-1 receptor (CB1) continue to be developed and characterized, the gap between the in vitro and in vivo data is widening, raising questions regarding translatability of their effects and biological relevance. Among the CB1 allosteric modulators, PSNCBAM-1 has received little attention regarding its effects in vivo. Recently, pregnenolone was reported to act as an allosteric modulator of CB1, blocking THC's effects in vitro and in vivo, highlighting the potential of CB1 allosteric modulators for treatment of cannabis intoxication. We investigated the pharmacological effects of PSNCBAM-1 and two structural analogs, RTICBM-15 and -28, as well as pregnenolone, in both signaling and behavioral assays including [35S]GTPγS binding, the cannabinoid tetrad and drug discrimination. While the CB1 allosteric modulator PSNCBAM-1 attenuated THC-induced anti-nociception and its structural analog RTICBM-28 reduced THC's potency in drug discrimination, most cannabinoid effects in mice were unaffected. In contrast to the mouse studies, PSNCBAM-1 and analogs insurmountably antagonized CP55,940- and THC-stimulated [35S]GTPγS binding and exhibited negative binding cooperativity with [3H]SR141716 with similar apparent affinities. Notably, RTICBM-28, which contains a cyano substitution at the 4-chlorophenyl position of PSNCBAM-1, exhibited enhanced binding cooperativity with CP55,940. In contrast to previous findings, pregnenolone did not block THC's effects in drug discrimination or [35S]GTPγS. These data further highlight the difficulty in translating pharmacological effects of CB1 allosteric modulators in vivo but confirm the established pharmacology of PSNCBAM-1 and analogs in molecular assays of CB1 receptor function.

Advancing the Use of Emergency Department Syndromic Surveillance Data, New York City, 2012-2016.

The use of syndromic surveillance has expanded from its initial purpose of bioterrorism detection. We present 6 use cases from New York City that demonstrate the value of syndromic surveillance for public health response and decision making across a broad range of health outcomes: synthetic cannabinoid drug use, heat-related illness, suspected meningococcal disease, medical needs after severe weather, asthma exacerbation after a building collapse, and Ebola-like illness in travelers returning from West Africa. The New York City syndromic surveillance system receives data on patient visits from all emergency departments (EDs) in the city. The data are used to assign syndrome categories based on the chief complaint and discharge diagnosis, and analytic methods are used to monitor geographic and temporal trends and detect clusters. For all 6 use cases, syndromic surveillance using ED data provided actionable information. Syndromic surveillance helped detect a rise in synthetic cannabinoid-related ED visits, prompting a public health investigation and action. Surveillance of heat-related illness indicated increasing health effects of severe weather and led to more urgent public health messaging. Surveillance of meningitis-related ED visits helped identify unreported cases of culture-negative meningococcal disease. Syndromic surveillance also proved useful for assessing a surge of methadone-related ED visits after Superstorm Sandy, provided reassurance of no localized increases in asthma after a building collapse, and augmented traditional disease reporting during the West African Ebola outbreak. Sharing syndromic surveillance use cases can foster new ideas and build capacity for public health preparedness and response.

Endocannabinoid Regulation of Reward and Reinforcement through Interaction with Dopamine and Endogenous Opioid Signaling.

The endocannabinoid system (eCB) is implicated in the mediation of both reward and reinforcement. This is evidenced by the ability of exogenous cannabinoid drugs to produce hedonia and maintain self-administration in both human and animal subjects. eCBs similarly facilitate behaviors motivated by reward through interaction with the mesolimbic dopamine (DA) and endogenous opioid systems. Indeed, eCB signaling in the ventral tegmental area stimulates activation of midbrain DA cells and promotes DA release in terminal regions such as the nucleus accumbens (NAc). DA transmission mediates several aspects of reinforced behavior, such as motivation, incentive salience, and cost-benefit calculations. However, much research suggests that endogenous opioid signaling underlies the hedonic aspects of reward. eCBs and their receptors functionally interact with opioid systems within the NAc to support reward, most likely through augmenting DA release. This review explores the interaction of these systems as it relates to reward and reinforcement and examines current literature regarding their role in food reward.

Therapeutic properties of cannabinoid drugs and marijuana in several disorders: A narrative review

Background. Anti-inflammatory, analgesic, anticonvulsant, and other effects have been attributed to cannabis, and so it has been widely used to treat several diseases. Objective. To assess the use and therapeutic effects of cannabinoid drugs and the cannabis plant in several diseases. Method. We carried out a narrative review of the literature that has reported the use of the cannabis plant (marijuana) and cannabinoid drugs (nabilone, cannabinol and dronabinol, among others). We conducted a search in Medline, Cochrane, SciELO and other web sites. Clinical, controlled, double-blind and randomized studies were included. The route of administration and the cannabinoid drugs used were assessed too. Results. Thirty-four studies were included. Nabilone was the cannabinoid drug more commonly used (12 studies), followed by delta-9-tetrahydrocannabinol (THC) (11 studies). It was also found that the marijuana plant and cannabinoid drugs were used to treat many symptoms or diseases. Two studies were reported for Gilles de la Tourette’s syndrome. Discussion and conclusion. Many scientific studies on the marijuana plant and cannabinoid drugs conclude that these are not as effective as conventional medications and thus their benefits should be taken with caution.

Synthesis and Pharmacological Profiling of the Metabolites of Synthetic Cannabinoid Drugs APICA, STS-135, ADB-PINACA, and 5F-ADB-PINACA.

Synthetic cannabinoids (SCs) containing a 1-pentyl-1-H substituted indole or indazole are abused around the world and are associated with an array of serious side effects. These compounds undergo extensive phase 1 metabolism after ingestion with little understanding whether these metabolites are contributing to the cannabimimetic activity of the drugs. This work presents the synthesis and pharmacological characterization of the major metabolites of two high concern SCs; APICA and ADB-PINACA. In a fluorometric assay of membrane potential, all metabolites that did not contain a carboxylic acid functionality retained potent activity at both the CB1 (EC50 = 14-787 nM) and CB2 (EC50 = 5.5-291 nM) receptors regardless of heterocyclic core or 3-carboxamide substituent. Of note were the 5-hydroxypentyl and 4-pentanone metabolites which showed significant increases in CB2 functional selectivity. These results suggest that the metabolites of SCs potentially contribute to the overall pharmacological profile of these drugs.

Pharmacogenetics of Cannabinoids.

Although the application of medical marijuana and cannabinoid drugs is controversial, it is a part of modern-day medicine. The list of diseases in which cannabinoids are promoted as a treatment is constantly expanding. Cases of significant improvement in patients with a very poor prognosis of glioma or epilepsy have already been described. However, the occurrence of side effects is still difficult to estimate, and the current knowledge of the therapeutic effects of cannabinoids is still insufficient. In our opinion, the answers to many questions and concerns regarding the medical use of cannabis can be provided by pharmacogenetics. Knowledge based on proteins and molecules involved in the transport, action, and metabolism of cannabinoids in the human organism leads us to predict candidate genes which variations are responsible for the presence of the therapeutic and side effects of medical marijuana and cannabinoid-based drugs. We can divide them into: receptor genes—CNR1, CNR2, TRPV1, and GPR55, transporters—ABCB1, ABCG2, SLC6A, biotransformation, biosynthesis, and bioactivation proteins encoded by CYP3A4, CYP2C19, CYP2C9, CYP2A6, CYP1A1, COMT, FAAH, COX2, ABHD6, ABHD12 genes, and also MAPK14. This review organizes the current knowledge in the context of cannabinoids pharmacogenetics according to individualized medicine and cannabinoid drugs therapy.

Identification of Novel Variants of the CB1 Cannabinoid Receptor in Cancer Cells

Cannabinoid receptors (CBRs) are G‐protein coupled receptors (GPCRs) that are activated by the binding of cannabinoid ligands. It has recently been shown that CB1, found mostly in the brain, and CB2, found mostly in white blood cells and the spleen, have been found to be overexpressed in different cancer models. It has been found that besides the wild‐type CB1, different, shorter versions of the CB1 protein, called CB1 splice variants, are also found in the human brain. However, their function is unknown and requires further investigation. Currently, there is no information available on the expression of these CB1 variants in cancer. Preliminary results using semi‐quantitative reverse transcription polymerase chain reaction (RTPCR) utilizing primers corresponding to CB1 brain variants was used to demonstrate that in several cancer lines of brain, pancreatic, and breast tissue, there were CB1 transcripts of varying sizes were, in fact, being expressed. High, inter‐cancer variations were observed; some cancer lines did not possess any of the constructs while others expressed brain specific variants, and some lines even expressed other potential variants of differing lengths. Based upon our analysis of the results, we hypothesize that in these cancer cells, variants identical to those observed in the brain were being expressed, and that different, cancer‐specific CB1 variants were also being expressed. Currently, we are identifying numerous PCR products obtained by cloning and sequencing. Eventually, the isolated novel variant CBR1 genes will be overexpressed in mammalian cells, and functional analysis of each variant receptor conducted. If successful, the physiological significance of these splice variants and their use as potential novel targets for cannabinoid anti‐cancer drug developments will be determined.Support or Funding Information[DoD‐W81XWH1110795, UAMS TRI ABCRP to AR‐P, P20 RR‐16460 INBRE, NIH/NIDA DA039143 to ARP and PLP]

Effects of JWH015 in cytokine secretion in primary human keratinocytes and fibroblasts and its suitability for topical/transdermal delivery.

BackgroundJWH015 is a cannabinoid (CB) receptor type 2 agonist that produces immunomodulatory effects. Since skin cells play a key role in inflammatory conditions and tissue repair, we investigated the ability of JWH015 to promote an anti-inflammatory and pro-wound healing phenotype in human primary skin cells.MethodsHuman primary keratinocytes and fibroblasts were stimulated with lipopolysaccharide. The mRNA expression of cannabinoid receptors was determined using RT-PCR. The effects of JWH015 (0.05, 0.1, 0.5, and 1 µM) in pro- and anti-inflammatory factors were tested in lipopolysaccharide-stimulated cells. A scratch assay, using a co-culture of keratinocytes and fibroblasts, was used to test the effects of JWH015 in wound healing. In addition, the topical and transdermal penetration of JWH015 was studied in Franz diffusion cells using porcine skin and LC-MS.ResultsThe expression of CB1 and CB2 receptors (mRNA) and the production of pro- and anti-inflammatory factors enhanced in keratinocytes and fibroblasts following lipopolysaccharide stimulation. JWH015 reduced the concentration of major pro-inflammatory factors (IL-6 and MCP-1) and increased the concentration of a major anti-inflammatory factor (TGF-β) in lipopolysaccharide-stimulated cells. JWH015 induced a faster scratch gap closure. These JWH015’seffects were mainly modulated through both CB1 and CB2 receptors. Topically administered JWH015 was mostly retained in the skin and displayed a sustained and low level of transdermal permeation.ConclusionsOur findings suggest that targeting keratinocytes and fibroblasts with cannabinoid drugs could represent a therapeutic strategy to resolve peripheral inflammation and promote tissue repair.

Selective Estrogen Receptor Modulators: Cannabinoid Receptor Inverse Agonists with Differential CB1 and CB2 Selectivity.

Selective estrogen receptor modulators (SERMs) are used to treat estrogen receptor (ER)-positive breast cancer and osteoporosis. Interestingly, tamoxifen and newer classes of SERMs also exhibit cytotoxic effects in cancers devoid of ERs, indicating a non-estrogenic mechanism of action. Indicative of a potential ER-independent target, reports demonstrate that tamoxifen binds to cannabinoid receptors (CBRs) with affinity in the low μM range and acts as an inverse agonist. To identify cannabinoids with improved pharmacological properties relative to tamoxifen, and further investigate the use of different SERM scaffolds for future cannabinoid drug development, this study characterized the affinity and activity of SERMs in newer structural classes at CBRs. Fourteen SERMs from five structurally distinct classes were screened for binding to human CBRs. Compounds from four of five SERM classes examined bound to CBRs. Subsequent studies fully characterized CBR affinity and activity of one compound from each class. Ospemifine (a triphenylethylene) selectively bound to CB1Rs, while bazedoxifine (an indole) bound to CB2Rs with highest affinity. Nafoxidine (a tetrahydronaphthalene) and raloxifene (RAL; a benzothiaphene) bound to CB1 and CB2Rs non-selectively. All four compounds acted as inverse agonists at CB1 and CB2Rs, reducing basal G-protein activity with IC50 values in the nM to low μM range. Ospemifine, bazedoxifene and RAL also acted as inverse agonists to elevate basal intracellular cAMP levels in intact CHO-hCB2 cells. The four SERMs examined also acted as CB1 and CB2R antagonists in the cAMP assay, producing rightward shifts in the concentration-effect curve of the CBR agonist CP-55,940. In conclusion, newer classes of SERMs exhibit improved pharmacological characteristics (e.g., in CBR affinity and selectivity) relative to initial studies with tamoxifen, and thus suggest that different SERM scaffolds may be useful for development of safe and selective drugs acting via CBRs.

Hemopressin Peptides as Modulators of the Endocannabinoid System and their Potential Applications as Therapeutic Tools.

The endocannabinoid system (ECS) is activated when natural arachidonic acid derivatives (endogenous cannabinoids or endocannabinoids) bind as lipophilic messengers to cannabinoid receptors CB1 and CB2. The ECS comprises many hydrolytic enzymes responsible for the endocannabinoids cleavage. These hydrolases, such as fatty acid amide hydrolase (FAAH) and monoacylglyceride lipase (MAGL), are possible therapeutic targets for the development of new drugs as indirect cannabinoid agonists. Recently, a new family of endocannabinoid modulators was discovered; the lead structure of this family is the nonapeptide hemopressin produced from enzymatic cleavage of the α-chain of hemoglobin and acting as negative allosteric modulator of CB1. Hemopressin shows several physiological effects, e.g., antinociception, hypophagy, and hypotension. However, it is still a matter of debate whether this peptide, isolated from the brain of rats, is a real neuromodulator of the ECS. Recent evidence indicates that hemopressin could be a by-product formed by chemical degradation of a longer peptide RVD-hemopressin during the extraction from the brain homolysate. Indeed, RVD-hemopressin is more active than hemopressin in certain biological tests and may bind to the same subsite as Rimonabant, which is an inverse agonist of CB1 and a μ-opioid receptor antagonist. These findings have stimulated several studies to verify this hypothesis and to evaluate possible therapeutic applications of hemopressin, its peptidic derivatives, and synthetic analogues, opening new perspectives to the development of novel cannabinoid drugs.

Cannabinoid signalling inhibits sarcoplasmic Ca2+ release and regulates excitation-contraction coupling in mammalian skeletal muscle.

Marijuana was found to cause muscle weakness, although the exact regulatory role of its receptors (CB1 cannabinoid receptor; CB1R) in the excitation-contraction coupling (ECC) of mammalian skeletal muscle remains unknown. We found that CB1R activation or its knockout did not affect muscle force directly, whereas its activation decreased the Ca2+ -sensitivity of the contractile apparatus and made the muscle fibres more prone to fatigue. We demonstrate that CB1Rs are not connected to the inositol 1,4,5-trisphosphate pathway either in myotubes or in adult muscle fibres. By contrast, CB1Rs constitutively inhibit sarcoplasmic Ca2+ release and sarcoplasmic reticulum Ca2+ ATPase during ECC in a Gi/o protein-mediated way in adult skeletal muscle fibres but not in myotubes. These results help with our understanding of the physiological effects and pathological consequences of CB1R activation in skeletal muscle and may be useful in the development of new cannabinoid drugs. Marijuana was found to cause muscle weakness, although it is unknown whether it affects the muscles directly or modulates only the motor control of the central nervous system. Although the presence of CB1 cannabinoid receptors (CB1R), which are responsible for the psychoactive effects of the drug in the brain, have recently been demonstrated in skeletal muscle, it is unclear how CB1R-mediated signalling affects the contraction and Ca²⁺ homeostasis of mammalian skeletal muscle. In the present study, we demonstrate that in vitro CB1R activation increased muscle fatigability and decreased the Ca2+ -sensitivity of the contractile apparatus, whereas it did not alter the amplitude of single twitch contractions. In myotubes, CB1R agonists neither evoked, nor influenced inositol 1,4,5-trisphosphate (IP3 )-mediated Ca2+ transients, nor did they alter excitation-contraction coupling. By contrast, in isolated muscle fibres of wild-type mice, although CB1R agonists did not evoke IP3 -mediated Ca2+ transients too, they significantly reduced the amplitude of the depolarization-evoked transients in a pertussis-toxin sensitive manner, indicating a Gi/o protein-dependent mechanism. Concurrently, on skeletal muscle fibres isolated from CB1R-knockout animals, depolarization-evoked Ca2+ transients, as well qas Ca2+ release flux via ryanodine receptors (RyRs), and the total amount of released Ca2+ was significantly greater than that from wild-type mice. Our results show that CB1R-mediated signalling exerts both a constitutive and an agonist-mediated inhibition on the Ca2+ transients via RyR, regulates the activity of the sarcoplasmic reticulum Ca2+ ATPase and enhances muscle fatigability, which might decrease exercise performance, thus playing a role in myopathies, and therefore should be considered during the development of new cannabinoid drugs.

Rapid and sensitive screening and confirmation of thirty-four aminocarbonyl/carboxamide (NACA) and arylindole synthetic cannabinoid drugs in human whole blood.

We describe the development and validation of a method for the screening and confirmation of a range of chemically diverse synthetic cannabinoid drugs in human whole blood. The method targets the better known arylindole compounds as well as the emerging aminocarbonyl/ carboxamide (NACA) compounds. The approach consists of two separate extraction procedures designed to optimize recovery of each of these two classes, followed by analysis by liquid chromatography-tandem mass spectrometry (LC-MS/MS). The most significant novel compounds added were AB-FUBINACA, ADBICA, 5 F-ADBICA, ADB-PINACA, ADB-FUBINACA, ADB-FUBINACA, 5 F-ADB-PINACA, 5 F-ADB-PINACA, AB-PINACA, AB-CHMINACA, and ADB-CHMINACA. A third procedure is described for the quantitative confirmation of those compounds for which deuterated internal standards permitted quantitative analysis, including JWH-018, JWH-122, JWH-081, JWH-210, AM-2201, XLR-11, and UR-144. The methods were successfully validated according to Scientific Working Group in Forensic Toxicology (SWGTOX) protocol for 34 compounds in common use in the United States in the period of 2014 and 2015, although other substances, unknown at the time may have been introduced to the market over the same time period. The method was determined to be free from carry-over between samples, and no interference was found from other common therapeutic abused or novel psychoactive drugs. The methods were applied to the analysis of 1142 blood samples from forensic investigations, including post-mortem examinations and driving impairment cases. The drugs most frequently detected were AB-CHMINACA (18.6%), ADB-CHMINACA (15%), XLR-11 (5.5%), AB-FUBINACA (4.5%), AB-PINACA (3.9%), and ADB-FUBINACA (2.3%). Copyright © 2016 John Wiley & Sons, Ltd.

Synthetic Cannabinoid Use in a Transitional Housing Shelter: A Survey to Characterize Awareness of Risks and Reasons for Use

Synthetic Cannabinoid Use in a Transitional Housing Shelter: A Survey to Characterize Awareness of Risks and Reasons for Use