CB1 Affinity Research Articles

Robust congregation influences of AB-PINACA and MDMB-4en-PINACA inhalation on neurobehavioral and cardiac disorders in mice

BackgroundA novel category of unusual cannabinoid substances was created to serve as marijuana alternatives due to its widespread availability, low price, pleasurable effects, and difficulty to be detected in regular urine testing for drugs, although more potential for abuse, toxicity, and behavioral alterations can result. It is more hazardous to multiple organ systems and has higher CB1 and CB2 receptor affinities than natural cannabinoids. So, the abuse potential, toxicity, and cardiac and nervous systems health hazards of two popular street herbs (AB-PINACA and MDMB-4en-PINACA) have been evaluated in mice.MethodsThirty male mice were separated into three equally sized groups indiscriminately: the control group: received no treatments, the AB-PINACA-treated group, and the MDMB-4en-PINACA-treated group. Treated groups were exposed to the two herbs for two consecutive days via inhalation to simulate natural human exposure. Cannabinoid tetrad tests and anxiety-like behavior were performed. Serum samples were obtained for cardiac enzymes measurement. Heart and brain tissue samples were harvested for the determination of oxidative stress markers, brain neurotransmitters, and histopathological findings.ResultsNociception and hypothermia were significantly influenced by both treatments. The locomotor activity decreased significantly with AB-PINACA inhalation, while the cataleptic effect increased significantly with MDMB-4en-PINACA inhalation. In addition, both treatments induced anxiety-like behavior. Both treatments induced alterations in brain neurotransmitter levels (glutamate, dopamine, and serotonin) and cardiac enzyme levels (CK-MB, troponin I). Histological changes showed neurodegenerative, necrotic, and infracted heart myocytes and degenerated muscle fibers, particularly with MDMB-4en-PINACA inhalation.ConclusionsAcute inhalation of street herbs containing AB-PINACA and MDMB-4en-PINACA induced neurobehavioral and cardiac disturbances, which were evident by changes in behavior, brain neurotransmitters, and heart enzymes, in addition to the degenerative histopathological changes in the brain and heart.

Insight into the mechanism of action of ORG27569 at the cannabinoid type one receptor utilising a unified mathematical model

Allosteric modulation of CB1 is therapeutically advantageous compared to orthosteric activation as it potentially offers reduced on-target adverse effects. ORG27569 is an allosteric modulator that increases orthosteric agonist binding to CB1 but decreases functional signalling. ORG27569 is characterised by a delay in disinhibition of agonist-induced cAMP inhibition (lag); however, the mechanism behind this kinetic lag is yet to be identified. We aimed to utilise a mathematical model to predict data and design in vitro experiments to elucidate mechanisms behind the unique signalling profile of ORG27569. The established kinetic ternary complex model includes the existence of a transitional state of CB1 bound to ORG27569 and CP55940 and was used to simulate kinetic cAMP data using NONMEM 7.4 and Matlab R2020b. These data were compared with empirical cAMP BRET data in HEK293 cells stably expressing hCB1. The pharmacometric model suggested that the kinetic lag in cAMP disinhibition by ORG27569 is caused by signal amplification in the cAMP assay and can be reduced by decreasing receptor number. This was confirmed experimentally, as reducing receptor number through agonist-induced internalisation resulted in a decreased kinetic lag by ORG27569. ORG27569 was found to have a similar interaction with CP55940 and the high efficacy agonist WIN55,212-2, and was suggested to have lower affinity for CB1 bound by the partial agonist THC compared to CP55940. Allosteric modulators have unique signalling profiles that are often difficult to interrogate exclusively in vitro. We have used a combined mathematical and in vitro approach to prove that ORG27569 causes a delay in disinhibition of agonist-induced cAMP inhibition due to large receptor reserve in this pathway. We also used the pharmacometric model to investigate the common phenomenon of probe dependence, to propose that ORG27569 binds with higher affinity to CB1 bound by high efficacy orthosteric agonists.

Hexahydrocannabinol Pharmacology, Toxicology, and Analysis: The First Evidence for a Recent New Psychoactive Substance.

During the last two years, hexahydrocannabinol (HHC), the hydrogenated derivative of tetrahydrocannabinol has been freely sold by internet websites as a "legal" replacement to THC and cannabis in a range of highly attractive branded and unbranded products, some of which are sold as "legal highs". Potentially, there could be a large demand for HHC products by individuals in Europe and internationally. Studies reporting HHC pharmacology, toxicology and analysis were identified from Pubmed and Scopus databases, and official international organizations' websites were considered. HHC showed the effects of the typical cannabinoid on the central nervous system, with lower potency than Δ9-THC. A few studies highlighted that 9(R)-HHC is more potent than 9(S)-HHC. This molecule showed an affinity for cannabinoid receptor CB1 both in vitro and in vivo, suggesting a possible therapeutic effect in several pathologies. However, the affinity for the CB1 receptor suggests a possible addiction potential, inducing the users to misuse it. Since actual intoxication cases have not yet been reported, the HHC harmful potential was not described, probably due to the lack of effective analytical methods to detect HHC in biological matrices. Conversely, different analytical assays were developed and validated to separate HHC epimers in natural and non-natural sources. Similarly to other NPS, the HHC represents a cheaper alternative to the controlled Δ9-THC. Its monitoring is a crucial challenge for toxicological and forensic purposes. To this concern, it is essential to further investigate HHC to support health providers in the identification of related intoxications.

MAM-2201 acute administration impairs motor, sensorimotor, prepulse inhibition, and memory functions in mice: a comparison with its analogue AM-2201

Rationale1-[(5-fluoropentyl)-1H-indol-3-yl](4-methyl-1-naphthalenyl) methanone (MAM-2201) is a potent synthetic cannabinoid receptor agonist illegally marketed in “spice” products and as “synthacaine” for its psychoactive effects. It is a naphthoyl-indole derivative which differs from its analogue 1-[(5-Fluoropentyl)-1H-indol-3-yl](1-naphthylenyl) methanone (AM-2201) by the presence of a methyl substituent on carbon 4 (C-4) of the naphthoyl moiety. Multiple cases of intoxication and impaired driving have been linked to AM-2201 and MAM-2201 consumption.ObjectivesThis study aims to investigate the in vitro (murine and human cannabinoid receptors) and in vivo (CD-1 male mice) pharmacodynamic activity of MAM-2201 and compare its effects with those induced by its desmethylated analogue, AM-2201.ResultsIn vitro competition binding studies confirmed that MAM-2201 and AM-2201 possess nanomolar affinity for both CD-1 murine and human CB1 and CB2 receptors, with preference for the CB1 receptor. In agreement with the in vitro binding data, in vivo studies showed that MAM-2201 induces visual, acoustic, and tactile impairments that were fully prevented by pretreatment with CB1 receptor antagonist/partial agonist AM-251, indicating a CB1 receptor mediated mechanism of action. Administration of MAM-2201 also altered locomotor activity and PPI responses of mice, pointing out its detrimental effect on motor and sensory gating functions and confirming its potential use liability. MAM-2201 and AM-2201 also caused deficits in short- and long-term working memory.ConclusionThese findings point to the potential public health burden that these synthetic cannabinoids may pose, with particular emphasis on impaired driving and workplace performance.

In vitro and in vivo pharmacology of nine novel synthetic cannabinoid receptor agonists

Synthetic cannabinoid receptor agonists (SCRAs) are novel psychoactive substances that bind to and activate CB1 receptors in the brain. The structural manipulations observed in newer SCRAs suggest that manufacturers have incorporated modern drug development techniques into their repertoire, often producing higher CB1 receptor affinity than Δ9-tetrahydrocannabinol (Δ9-THC). This study examined nine SCRAs recently detected by forensic surveillance, some of which caused fatalities: 5F-MDMB-PICA, FUB-144, 5F-MMB-PICA, MMB-4en-PICA, MMB-FUBICA, 5F-EDMB-PINACA, APP-BINACA, MDMB-4en-PINACA, and FUB-AKB48. Compounds were evaluated for CB1 and CB2 receptor binding affinity and functional activation and for their effects on body temperature, time course, and pharmacological equivalence with Δ9-THC in Δ9-THC drug discrimination in mice. All SCRAs bound to and activated CB1 and CB2 receptors with high affinity, with similar or greater affinity for CB2 than CB1 receptors and stimulated [35S]GTPγS binding in CB1 and CB2 expressing cell membranes. All compounds produced hypothermia, with shorter latency to peak effects for SCRAs than Δ9-THC. All SCRAs fully substituted for Δ9-THC in drug discrimination at one or more doses. Rank order potency in producing in vivo effects mostly aligned with rank order CB1 receptor affinities. Potencies for Δ9-THC-like discriminative stimulus effects were similar across sex except Δ9-THC was more potent in females and 5F-MMB-PICA was more potent in males. In summary, 5F-EMDB-PINACA, 5F-MDMB-PICA, MDMB-4en-PINACA, FUB-144, FUB-AKB48, 5F-MMB-PICA, MMB-4en-PICA, and MMB-FUBICA are potent and efficacious SCRAs with pharmacology like that of past SCRAs that have been abused in humans. In contrast, APP-BINACA was efficacious, but had lower potency than most past SCRAs.

Treatment with Cannabidiol Results in an Antioxidant and Cardioprotective Effect in Several Pathophysiologies.

Cannabis sativa has chemically active compounds called cannabinoids, where Δ9- tetrahydrocannabinol (THC) and Cannabidiol (CBD) are the major ones responsible for the various pharmacological effects. The endocannabinoid system is an endogenous system considered a unique and widespread homeostatic physiological regulator. It is made up of type 1 (CB1) and type 2 (CB2) cannabinoid receptors. CBD, in turn, has a low affinity for CB1 and CB2 receptors, and regulates the effects arising from THC as a CB1 partial agonist, which are tachycardia, anxiety, and sedation. It also acts as a CB2 inverse agonist, resulting in anti-inflammatory effects. Furthermore, its anticonvulsant, neuroprotective, antipsychotic, antiemetic, anxiolytic, anticancer, and antioxidant effects seem to be linked to other discovered receptors such as GRP55, 5TH1a, TRPV I, TRPV II and the regulation of the intracellular concentration of Ca2+. Regarding oxidative stress, O2- can act as an oxidizing agent, being reduced to hydrogen peroxide (H2O2), or as a reducing agent, donating its extra electron to NO to form peroxynitrite (ONOO-). The ONOO- formed is capable of oxidizing proteins, lipids, and nucleic acids, causing several cell damages. In this sense, CBD can prevent cardiac oxidative damage in many conditions, such as hypertension, diabetes, or even through the cardiotoxic effects induced by chemotherapy, which makes it a potential target for future clinical use to minimize the deleterious effects of many pathophysiologies.

Cannabis sativa L. Bioactive Compounds and Their Protective Role in Oxidative Stress and Inflammation.

Cannabis (Cannabis sativa L.) plants from the family Cannabidaceae have been used since ancient times, to produce fibers, oil, and for medicinal purposes. Psychoactive delta-9-tetrahydrocannabinol (THC) and nonpsychoactive cannabidiol (CBD) are the main pharmacologically active compounds of Cannabis sativa. These compounds have, for a long time, been under extensive investigation, and their potent antioxidant and inflammatory properties have been reported, although the detailed mechanisms of their actions have not been fully clarified. CB1 receptors are suggested to be responsible for the analgesic effect of THC, while CB2 receptors may account for its immunomodulatory properties. Unlike THC, CBD has a very low affinity for both CB1 and CB2 receptors, and behaves as their negative allosteric modulator. CBD activity, as a CB2 receptor inverse agonist, could be important for CBD anti-inflammatory properties. In this review, we discuss the chemical properties and bioavailability of THC and CBD, their main mechanisms of action, and their role in oxidative stress and inflammation.

Identification of AD-18, 5F-MDA-19, and pentyl MDA-19 in seized materials after the class-wide ban of synthetic cannabinoids in China.

To curb the manufacturing, trafficking, and abuse of synthetic cannabinoids, China implemented a class-wide regulation on synthetic cannabinoids in July 2021. Recently, three different types of synthetic cannabinoid analogs that were not covered by the generic definitions were detected in seized powdered and e-liquid materials. These derivatives included 2-(2-(1-(4-fluorobenzyl)-1H-indol-3-yl)acetamido)-3,3-dimethylbutanamide (AD-18), N'-(1-(5-fluoropentyl)-2-oxoindolin-3-ylidene)benzohydrazide (5F-MDA-19), and N'-(2-oxo-1-pentylindolin-3-ylidene)benzohydrazide (pentyl MDA-19). Identification was based on ultra-high-performance liquid chromatography-quadrupole time-of-flight-mass spectrometry (UHPLC-QTOF-MS), gas chromatography-mass spectrometry (GC-MS), nuclear magnetic resonance spectroscopy (NMR), and Fourier transform infrared spectroscopy (FT-IR). AD-18 is a methylene analog of ADB-FUBICA. No chemical or pharmacological data about AD-18 and 5F-MDA-19 have appeared until now, making this the first report on these two compounds. Pentyl MDA-19 has previously been reported to have high affinity for cannabinoid CB1 and CB2 receptors, but this is the first report of its presence in the recreational drug market. Moreover, the collision-induced dissociation (CID) and electron ionization (EI) characteristic fragmentation routes of AD-18 and the other two MDA-19 derivatives were also discussed to facilitate forensic laboratories in their identification of other substances with a similar structure in their case work.

Structure-activity relationships for 5F-MDMB-PICA and its 5F-pentylindole analogs to induce cannabinoid-like effects in mice.

Synthetic cannabinoid receptor agonists (SCRAs) are an evolving class of new psychoactive substances found on recreational drug markets worldwide. The indole-containing compound, 5F-MDMB-PICA, is a popular SCRA associated with serious medical consequences, including overdose and hospitalizations. In vitro studies reveal that 5F-MDMB-PICA is a potent agonist at cannabinoid type 1 receptors (CB1), but little information exists regarding in vivo pharmacology of the drug. To this end, we examined the in vitro and in vivo cannabinoid-like effects produced by 5F-MDMB-PICA and related 5F-pentylindole analogs with differing composition of the head group moiety (i.e., 5F-NNEI, 5F-SDB-006, 5F-CUMYL-PICA, 5F-MMB-PICA). In mouse brain membranes, 5F-MDMB-PICA and its analogs inhibited binding to [3H]rimonabant-labeled CB1 and displayed agonist actions in [35S]GTPγS functional assays. 5F-MDMB-PICA exhibited the highest CB1 affinity (Ki = 1.24 nM) and functional potency (EC50 = 1.46 nM), but head group composition markedly influenced activity in both assays. For example, the 3,3-dimethylbutanoate (5F-MDMB-PICA) and cumyl (5F-CUMYL-PICA) head groups engendered high CB1 affinity and potency, whereas a benzyl (5F-SDB-006) head group did not. In C57BL/6J mice, all 5F-pentylindole SCRAs produced dose- and time-dependent hypothermia, catalepsy, and analgesia that were reversed by rimonabant, indicating CB1 involvement. In vitro Ki and EC50 values were positively correlated with in vivo ED50 potency estimates. Our findings demonstrate that 5F-MDMB-PICA is a potent SCRA, and subtle alterations to head group composition can have profound influence on pharmacological effects at CB1. Importantly, measures of CB1 binding and efficacy in mouse brain tissue seem to accurately predict in vivo drug potency in this species.

NNL-3: A Synthetic Intermediate or a New Class of Hydroxybenzotriazole Esters with Cannabinoid Receptor Activity?

Synthetic cannabinoid receptor agonists (SCRAs) remain a prolific class of new psychoactive substances (NPS) and continue to expand rapidly. Despite the recent identification of hydroxybenzotriazole (HOBt) containing SCRAs in synthetic cannabis samples, there is currently no information regarding the pharmacological profile of these NPS with respect to human CB1 and CB2 receptors. In the current study, a series consisting of seven HOBt indole-, indazole-, and 7-azaindole-carboxylates bearing a range of N-alkyl substituents were synthesized and pharmacologically evaluated. Competitive binding assays at CB1 and CB2 demonstrated that all analogues except a 2-methyl-substituted derivative had low affinity for CB1 (Ki = 3.80-43.7 μM) and CB2 (Ki = 2.75-18.2 μM). A fluorometric functional assay revealed that 2-methylindole- and indole-derived HOBt carboxylates were potent and efficacious agonists of CB1 (EC50 = 12.0 and 63.7 nM; Emax = 118 and 120%) and CB2 (EC50 = 10.9 and 321 nM; Emax = 91 and 126%). All other analogues incorporating indazole and 7-azaindole cores and bearing a range of N1-substituents showed relatively low potency for CB1 and CB2. Additionally, a reporter assay monitoring β-arrestin 2 (βarr2) recruitment to the receptor revealed that the 2-methylindole example was the most potent and efficacious at CB1 (EC50 = 131 nM; Emax = 724%) and the most potent at CB2 (EC50 = 38.2 nM; Emax = 51%). As with the membrane potential assay, the indazole and other indole HOBt carboxylates were considerably less potent at both receptors, and analogues comprising a 7-azaindole core showed little activity. Taken together, these data suggest that NNL-3 demonstrates little CB1 receptor activity and is unlikely to be psychoactive in humans. NNL-3 is likely an unintended SCRA manufacturing byproduct. However, the synthesis of NNL-3 analogues proved simple and general, and some of these showed potent cannabimetic profiles in vitro, indicating that HOBt esters of this type may represent an emerging class of SCRA NPS.

Carbon-silicon switch led to the discovery of novel synthetic cannabinoids with therapeutic effects in a mouse model of multiple sclerosis

Cannabinoids are widely studied as therapeutic agents for the treatment of various diseases. Among them, THC and CBD are two important phytocannabinoids which have served as structural templates for the design of synthetic analogs. In this study, we designed and synthesized a variety of novel cannabinoids based on the structural backbones of THC and CBD using the carbon-silicon switch strategy. A dimethyl silyl group was introduced as the tail group and two series of novel compounds were designed and synthesized, which showed a wide range of binding affinity for CB1 and CB2 receptors. Among them, compound 15b was identified as a non-selective CB1 and CB2 agonist and 38b as a selective agonist for the CB2 receptor. Preliminary screening showed that both compounds have improved metabolic stability than their carbon analogs and good in vivo pharmacokinetic profiles. Furthermore, both 15b and 38b significantly alleviated the phenotype of experimental autoimmune encephalomyelitis (EAE) in mice.

Characterization of cannabinoid receptors expressed in Ewing sarcoma TC-71 and A-673 cells as potential targets for anti-cancer drug development

AimsCharacterizing cannabinoid receptors (CBRs) expressed in Ewing sarcoma (EWS) cell lines as potential targets for anti-cancer drug development. Main methodsCBR affinity and function were examined by competitive binding and G-protein activation, respectively. Cannabinoid-mediated cytotoxicity and cell viability were evaluated by LDH, and trypan blue assays, respectively. Key findingsqRT-PCR detected CB1 (CB1R) and CB2 receptor (CB2R) mRNA in TC-71 cells. However, binding screens revealed that CBRs expressed exhibit atypical properties relative to canonical receptors, because specific binding in TC-71 could only be demonstrated by the established non-selective CB1/CB2R radioligand [3H]WIN-55,212-2, but not CB1/CB2R radioligand [3H]CP-55,940. Homologous receptor binding demonstrated that [3H]WIN-55,212-2 binds to a single site with nanomolar affinity, expressed at high density. Further support for non-canonical CBRs expression is provided by subsequent binding screens, revealing that only 9 out of 28 well-characterized cannabinoids with high affinity for canonical CB1 and/or CB2Rs were able to displace [3H]WIN-55,212-2, whereas two ligands enhanced [3H]WIN-55,212-2 binding. Five cannabinoids producing the greatest [3H]WIN-55,212-2 displacement exhibited high nanomolar affinity (Ki) for expressed receptors. G-protein modulation and adenylyl cyclase assays further indicate that these CBRs exhibit distinct signaling/functional profiles compared to canonical CBRs. Importantly, cannabinoids with the highest affinity for non-canonical CBRs reduced TC-71 viability and induced cytotoxicity in a time-dependent manner. Studies in a second EWS cell line (A-673) showed similar atypical binding properties of expressed CBRs, and cannabinoid treatment produced cytotoxicity. SignificanceCannabinoids induce cytotoxicity in EWS cell lines via non-canonical CBRs, which might be a potential therapeutic target to treat EWS.

Pharmacokinetics and pharmacodynamics of the synthetic cannabinoid, 5F-MDMB-PICA, in male rats

5F-MDMB-PICA is a popular synthetic cannabinoid associated with analytically confirmed intoxications. In vitro studies show 5F-MDMB-PICA is a potent cannabinoid-1 receptor (CB1) agonist, but little information is available about in vivo pharmacokinetics and pharmacodynamics. To this end, the present study had three aims: 1) to develop a validated method for detection of 5F-MDMB-PICA and its metabolites in rat plasma, 2) to utilize the method for investigating pharmacokinetics of 5F-MDMB-PICA in rats, and 3) to relate 5F-MDMB-PICA pharmacokinetics to pharmacodynamic effects. 5F-MDMB-PICA and its metabolites were quantified using liquid chromatography tandem mass spectrometry (LC-MS/MS) and method validation followed forensic standards. Male Sprague-Dawley rats bearing surgically implanted jugular catheters and subcutaneous (s.c.) temperature transponders received 5F-MDMB-PICA (50, 100, or 200 μg/kg, s.c.) or its vehicle. Blood samples were drawn at 15, 30, 60, 120, 240, and 480 min post-injection, and plasma was assayed using LC-MS/MS. At each blood draw, body temperature, and catalepsy scores were recorded. Maximum plasma concentrations (Cmax) of 5F-MDMB-PICA rose linearly with increasing dose (1.72–6.20 ng/mL), and plasma half-life (t1/2) ranged from 400 to 1000 min 5F-MDMB-PICA-3,3-dimethylbutanoic acid and 5OH-MDMB-PICA were the only metabolites detected, and plasma concentrations were much lower than the parent drug. 5F-MDMB-PICA induced robust hypothermia and catalepsy-like symptoms that were significantly correlated with concentrations of 5F-MDMB-PICA. Radioligand binding in rat brain membranes revealed 5F-MDMB-PICA displays high affinity for CB1 (IC50 = 2 nM) while metabolites do not. In summary, 5F-MDMB-PICA is a potent CB1 agonist in rats whose pharmacodynamic effects are related to circulating concentrations of the parent drug and not its metabolites.

Tricyclic Pyrazole-Based Compounds as Useful Scaffolds for Cannabinoid CB1/CB2 Receptor Interaction.

Cannabinoids comprise different classes of compounds, which aroused interest in recent years because of their several pharmacological properties. Such properties include analgesic activity, bodyweight reduction, the antiemetic effect, the reduction of intraocular pressure and many others, which appear correlated to the affinity of cannabinoids towards CB1 and/or CB2 receptors. Within the search aiming to identify novel chemical scaffolds for cannabinoid receptor interaction, the CB1 antagonist/inverse agonist pyrazole-based derivative rimonabant has been modified, giving rise to several tricyclic pyrazole-based compounds, most of which endowed of high affinity and selectivity for CB1 or CB2 receptors. The aim of this review is to present the synthesis and summarize the SAR study of such tricyclic pyrazole-based compounds, evidencing, for some derivatives, their potential in the treatment of neuropathic pain, obesity or in the management of glaucoma.

Cannabidiol and the Canonical WNT/β-Catenin Pathway in Glaucoma.

Glaucoma is a progressive neurodegenerative disease which constitutes the main frequent cause of irreversible blindness. Recent findings have shown that oxidative stress, inflammation and glutamatergic pathway play key roles in the causes of glaucoma. Recent studies have shown a down regulation of the WNT/β-catenin pathway in glaucoma, associated with overactivation of the GSK-3β signaling. WNT/β-catenin pathway is mainly associated with oxidative stress, inflammation and glutamatergic pathway. Cannabidiol (CBD) is a non-psychotomimetic phytocannabinoid derived from Cannabis sativa plant which possesses many therapeutic properties across a range of neuropsychiatric disorders. Since few years, CBD presents an increased interest as a possible drug in anxiolytic disorders. CBD administration is associated with increase of the WNT/β-catenin pathway and decrease of the GSK-3β activity. CBD has a lower affinity for CB1 but can act through other signaling in glaucoma, including the WNT/β-catenin pathway. CBD downregulates GSK3-β activity, an inhibitor of WNT/β-catenin pathway. Moreover, CBD was reported to suppress pro-inflammatory signaling and neuroinflammation, oxidative stress and glutamatergic pathway. Thus, this review focuses on the potential effects of cannabidiol, as a potential therapeutic strategy, on glaucoma and some of the presumed mechanisms by which this phytocannabinoid provides its possible benefit properties through the WNT/β-catenin pathway.

Bioactive Chemical Composition of Cannabis Extracts and Cannabinoid Receptors.

Cannabis is widely used as a therapeutic drug, especially by patients suffering from psychiatric and neurodegenerative diseases. However, the complex interplay between phytocannabinoids and their targets in the human receptome remains largely a mystery, and there have been few investigations into the relationship between the chemical composition of medical cannabis and the corresponding biological activity. In this study, we investigated 59 cannabis samples used by patients for medical reasons. The samples were subjected to extraction (microwave and supercritical carbon dioxide) and chemical analyses, and the resulting extracts were assayed in vitro using the CB1 and CB2 receptors. Using a partial least squares regression analysis, the chemical compositions of the extracts were then correlated to their corresponding cannabinoid receptor activities, thus generating predictive models that describe the receptor potency as a function of major phytocannabinoid content. Using the current dataset, meaningful models for CB1 and CB2 receptor agonism were obtained, and these reveal the insignificant relationships between the major phytocannabinoid content and receptor affinity for CB1 but good correlations between the two at CB2 receptors. These results also explain the anomalies between the receptor activities of pure phytocannabinoids and cannabis extracts. Furthermore, the models for CB1 and CB2 agonism in cannabis extracts predict the cannabinoid receptor activities of individual phytocannabinoids with reasonable accuracy. Here for the first time, we disclose a method to predict the relationship between the chemical composition, including phytocannabinoids, of cannabis extracts and cannabinoid receptor responses.

English

Cannabis sp. has important pharmacological activities, so it has been the focus of attention of the scientific community. Through the search for new drugs, it was found that cannabinoids present in the plant can modulate transient potential receptors (TPR). Cannabidiol (CBD), also known as “medical marijuana”, represents the second most abundant phytocannabinoid of the Cannabis plant and it is widely used in the management of pain, nausea and migraine in cancer patients. In fact, CBD exhibits various therapeutic effects and constitutes up to 40% of Cannabis extracts and it is devoid of the typical psychological effects of Cannabis used in social use as a psychoactive drug, and has low affinity for endocannabinoid receptors CB1 and CB2. Thus, this article aims to conduct an integrative review of CBD and its potential benefits for human health. The results of this research confirmed CBD therapeutic actions in diseases such as schizophrenia, anxiety, epilepsy and motor disorders such as Parkinson's disease, Alzheimer's disease, multiple sclerosis, neuropathic pain, childhood convulsive disorders, Lennox-Gastaut and Dravet syndromes. Thus, cannabidiol has an important relevance for medical applications and also has anti-inflammatory, antioxidant, anticonvulsant, anxiolytic, neuroprotective, antipsychotic, antiemetic, analgesic and antibiotic activities. Key words: Medical marijuana, cannabinoids, Cannabidiol (CBD), medicinal use. &nbsp

Isolation of a High-Affinity Cannabinoid for the Human CB1 Receptor from a Medicinal Cannabis sativa Variety: Δ9-Tetrahydrocannabutol, the Butyl Homologue of Δ9-Tetrahydrocannabinol.

The butyl homologues of Δ9-tetrahydrocannabinol, Δ9-tetrahydrocannabutol (Δ9-THCB), and cannabidiol, cannabidibutol (CBDB), were isolated from a medicinal Cannabis sativa variety (FM2) inflorescence. Appropriate spectroscopic and spectrometric characterization, including NMR, UV, IR, ECD, and HRMS, was carried out on both cannabinoids. The chemical structures and absolute configurations of the isolated cannabinoids were confirmed by comparison with the spectroscopic data of the respective compounds obtained by stereoselective synthesis. The butyl homologue of Δ9-THC, Δ9-THCB, showed an affinity for the human CB1 (Ki = 15 nM) and CB2 receptors (Ki = 51 nM) comparable to that of (-)-trans-Δ9-THC. Docking studies suggested the key bonds responsible for THC-like binding affinity for the CB1 receptor. The formalin test in vivo was performed on Δ9-THCB in order to reveal possible analgesic and anti-inflammatory properties. The tetrad test in mice showed a partial agonistic activity of Δ9-THCB toward the CB1 receptor.

Cannabinoid Antagonist Drug Discrimination in Nonhuman Primates.

Despite a growing acceptance that withdrawal symptoms can emerge following discontinuation of cannabis products, especially in high-intake chronic users, there are no Food and Drug Administration (FDA)-approved treatment options. Drug development has been hampered by difficulties studying cannabis withdrawal in laboratory animals. One preclinical approach that has been effective in studying withdrawal from drugs in several pharmacological classes is antagonist drug discrimination. The present studies were designed to examine this paradigm in squirrel monkeys treated daily with the long-acting CB1 agonist AM2389 (0.01 mg/kg) and trained to discriminate the CB1 inverse agonist/antagonist rimonabant (0.3 mg/kg) from saline. The discriminative-stimulus effects of rimonabant were both dose and time dependent and, importantly, could be reproduced by discontinuation of agonist treatment. Antagonist substitution tests with the CB1 neutral antagonists AM4113 (0.03-0.3 mg/kg), AM6527 (0.03-1.0 mg/kg), and AM6545 (0.03-1.0 mg/kg) confirmed that the rimonabant discriminative stimulus also could be reproduced by CB1 antagonists lacking inverse agonist action. Agonist substitution tests with the phytocannabinoid ∆9-tetrahydrocannabinol (0.1-1.0 mg/kg), synthetic CB1 agonists nabilone (0.01-0.1 mg/kg), AM4054 (0.01-0.03 mg/kg), K2/Spice compound JWH-018 (0.03-0.3 mg/kg), FAAH-selective inhibitors AM3506 (0.3-5.6 mg/kg), URB597 (3.0-5.6 mg/kg), and nonselective FAAH/MGL inhibitor AM4302 (3.0-10.0 mg/kg) revealed that only agonists with CB1 affinity were able to reduce the rimonabant-like discriminative stimulus effects of withholding daily agonist treatment. Although the present studies did not document physiologic disturbances associated with withdrawal, the results are consistent with the view that the cannabinoid antagonist drug discrimination paradigm provides a useful screening procedure for examining the ability of candidate medications to attenuate the interoceptive stimuli provoked by cannabis discontinuation. SIGNIFICANCE STATEMENT: Despite a growing acceptance that withdrawal symptoms can emerge following the discontinuation of cannabis products, especially in high-intake chronic users, there are no FDA-approved pharmacotherapies to assist those seeking treatment. The present studies systematically examined cannabinoid antagonist drug discrimination, a preclinical animal model that is designed to appraise the ability of candidate medications to attenuate the interoceptive effects that accompany abrupt cannabis abstinence.

The chemistry and pharmacology of putative synthetic cannabinoid receptor agonist (SCRA) new psychoactive substances (NPS) 5F-PY-PICA, 5F-PY-PINACA, and their analogs.

5F-PY-PICA and 5F-PY-PINACA are pyrrolidinyl 1-(5-fluoropentyl)ind (az)ole-3-carboxamides identified in 2015 as putative synthetic cannabinoid receptor agonist (SCRA) new psychoactive substances (NPS). 5F-PY-PICA, 5F-PY-PINACA, and analogs featuring variation of the 1-alkyl substituent or contraction, expansion, or scission of the pyrrolidine ring were synthesized and characterized by nuclear magnetic resonance (NMR) spectroscopy and liquid chromatography-quadrupole time-of-flight-mass spectrometry (LC-QTOF-MS). In competitive binding experiments against HEK293 cells expressing human cannabinoid receptor type 1 (hCB1 ) or type 2 (hCB2 ), all analogs showed minimal affinity for CB1 (pKi <5), although several demonstrated moderate CB2 binding (pKi 5.45-6.99). In fluorescence-based membrane potential assays using AtT20-hCB1 or -hCB2 cells, none of the compounds (at 10μM) produced an effect >50% of the classical cannabinoid agonist CP55,940 (at 1μM) at hCB1 , although several showed slightly higher relative efficacy at hCB2 . Expansion of the pyrrolidine ring of 5F-PY-PICA to an azepane (8) conferred the greatest hCB2 affinity (pKi 6.99) and activity (pEC50 7.54, Emax 72%) within the series. Unlike other SCRA NPS evaluated in vivo using radio biotelemetry, 5F-PY-PICA and 5F-PY-PINACA did not produce cannabimimetic effects (hypothermia, bradycardia) in mice at doses up to 10mg/kg.