The Spicy Story of Cannabimimetic Indoles

Cannabinoids and General Anesthetics: Revisiting Molecular Mechanisms of Their Pharmacological Interactions

Cannabis has been used for recreation and medical purposes for more than a millennium across the world; however, its use's consequences remain poorly understood. Although a growing number of surgical patients are regular cannabis consumers, little is known regarding the pharmacological interactions between cannabis and general anesthetics; consequently, there is not a solid consensus among anesthesiologists on the perioperative management of these patients. The existing evidence about the molecular mechanisms underlying pharmacological interactions between cannabinoids and anesthetic agents, both in animal models and in humans, shows divergent results. While some animal studies have demonstrated that phytocannabinoids (tetrahydrocannabinol [THC], cannabidiol [CBD], and cannabinol [CBN]) potentiate the anesthetic effects of inhalation and intravenous anesthetics, while others have found effects comparable with what has been described in humans so far. Clinical studies and case reports have consistently shown increased requirements of GABAergic anesthetic drugs (isoflurane, sevoflurane, propofol, midazolam) to achieve adequate levels of clinical anesthesia. Several potential molecular mechanisms have been proposed to explain the effects of these interactions. However, it is interesting to mention that in humans, it has been observed that the ingestion of THC enhances the hypnotic effect of ketamine. Animal studies have reported that cannabinoids enhance the analgesic effect of opioids due to a synergistic interaction of the endogenous cannabinoid system (ECS) with the endogenous opioid system (EOS) at the spinal cord level and in the central nervous system. However, human data reveals that cannabis users show higher scores of postoperative pain intensity as well as increased requirements of opioid medication for analgesia. This review aims to improve understanding of the molecular mechanisms and pharmacological interactions between cannabis and anesthetic drugs and the clinical outcomes that occur when these substances are used together.

Effects of Δ9-Tetrahydrocannabinol and the Aminoalkylindole K2/Spice Constituent JWH-073 on Cardiac Tissue and Mesenteric Vascular Reactivity

Background: Although use of Cannabis sativa is not associated with serious adverse effects, recreational use of aminoalkylindole (AAI) cannabinoid receptor agonists found in K2/Spice herbal blends has been reported to cause adverse cardiovascular events, including angina, arrhythmia, changes in blood pressure, ischemic stroke, and myocardial infarction. Δ9-Tetrahydrocannabinol (Δ9-THC) is the primary CB1 agonist found in cannabis and JWH-073 is one of the AAI CB1 agonists found in K2/Spice brands sold to the public. Methods: This study used in vitro, in vivo, and ex vivo approaches to investigate potential differences on cardiac tissue and vascular effects betweenJWH-073 and Δ9-THC. Male C57BL/6 mice were treated with JWH-073 or Δ9-THC and cardiac injury was assessed by histology. Effects of JWH-073 and Δ9-THC on H9C2 cell viability and ex vivo mesenteric vascular reactivity were also determined. Results: JWH-073 or Δ9-THC induced typical cannabinoid effects of antinociception and hypothermia but did not promote death of cardiac myocytes. No differences in cell viability were observed in cultured H9C2 cardiac myocytes after 24 h of treatment. In isolated mesenteric arteries from drug-naive animals, JWH-073 produced significantly greater maximal relaxation (96%±2% vs. 73%±5%, p<0.05) and significantly greater inhibition of phenylephrine-mediated maximal contraction (Control 174%±11%KMAX) compared with Δ9-THC (50%±17% vs. 119%±16%KMAX, p<0.05). Discussion: These findings suggest that neither cannabinoid at the concentrations/dose studied caused cardiac cell death, but JWH-073 has the potential for greater vascular adverse events than Δ9-THC through an increased vasodilatory effect.

Correction: Howlett et al. The Spicy Story of Cannabimimetic Indoles. Molecules 2021, 26, 6190

Missing Conflicts of Interest [...].

Exploring the versatile roles of the endocannabinoid system and phytocannabinoids in modulating bacterial infections

The endocannabinoid system (ECS), initially identified for its role in maintaining homeostasis, particularly in regulating brain function, has evolved into a complex orchestrator influencing various physiological processes beyond its original association with the nervous system. Notably, an expanding body of evidence emphasizes the ECS's crucial involvement in regulating immune responses. While the specific role of the ECS in bacterial infections remains under ongoing investigation, compelling indications suggest its active participation in host-pathogen interactions. Incorporating the ECS into the framework of bacterial pathogen infections introduces a layer of complexity to our understanding of its functions. While some studies propose the potential of cannabinoids to modulate bacterial function and immune responses, the outcomes inherently hinge on the specific infection and cannabinoid under consideration. Moreover, the bidirectional relationship between the ECS and the gut microbiota underscores the intricate interplay among diverse physiological processes. The ECS extends its influence far beyond its initial discovery, emerging as a promising therapeutic target across a spectrum of medical conditions, encompassing bacterial infections, dysbiosis, and sepsis. This review comprehensively explores the complex roles of the ECS in the modulation of bacteria, the host's response to bacterial infections, and the dynamics of the microbiome. Special emphasis is placed on the roles of cannabinoid receptor types 1 and 2, whose signaling intricately influences immune cell function in microbe-host interactions.

Synthesis of novel indol-3-acetamido analogues as potent anticancer agents, biological evaluation and molecular modeling studies

Cannabinoids bind to cannabinoid receptors CB1 and CB2 and their antitumoral activity has been reported against some various cancer cell lines. Some synthetic cannabinoids possessing indole rings such as JWH-015 and JWH-133 particularly bind to the cannabinoid CB2 receptor and it was reported that they inhibit the proliferation and growth of various cancer cells without their psychoactive effects. However, the pharmacological action mechanisms of the cannabinoids are completely unknown. In this study, we report the synthesis of some new cannabinoidic novel indoles and evaluate their anticancer activity on various cancerous and normal cell lines (U87, RPMI 8226, HL60 and L929) using several cellular and molecular assays including MTT assay, real-time q-PCR, scratch assay, DAPI assay, Annexin V-PE/7AAD staining, caspase3/7 activity tests. Our findings indicated that compounds 7, 10, 13, 16, and 17 could reduce cell viability effectively. Compound 17 markedly increased proapoptotic genes (BAX, BAD, and BIM), tumor suppressor gene (p53) expression levels as well as the BAX/BCL-2 ratio in U87 cells. In addition, 17 inhibited cell migration. Based on these results, 17 was chosen for determining the mechanism of cell death in U87 cells. DAPI and Annexin V-7AAD staining results showed that 17 induced apoptosis, moreover activated caspase 3/7 significantly. Hence, compound 17, was selected as a lead compound for further pharmacomodulation. To rationalize the observed biological activities of 17, our study also included a comprehensive analysis using molecular docking and MD simulations. This integrative approach revealed that 17 fits tightly into the active site of the CB2 receptor and is involved in key interactions that may be responsible for its anti-proliferative effects.

Synthetic cannabinoids in hair-Prevalence of use in abstinence control programs for driver's license regranting in Germany

Although the use, structural variety, and prevalence of synthetic cannabinoids (SCs) have steadily increased on the drug market, they are rarely analyzed in abstinence control programs for driver's license regranting. The aim of this study was to determine the SC prevalence in these programs by analyzing hair samples collected between March 2020 and March 2021 from various regions in Germany, mainly Bavaria (40%). Specimens were analyzed quantitatively for drugs of abuse and qualitatively for 107 SCs. Hair samples were screened by liquid chromatography-tandem mass spectrometry (LC-MS/MS), and to search for unknown SC analogs, positive samples were additionally screened by liquid chromatography-high resolution time of flight mass spectrometry (LC-qTOF/MS). The analysis of 5097 hair samples resulted in 181 SC detections (3.6%), showing a wide range of 44 SCs, with up to 13 different compounds found in a single sample. The most prevalent compounds were 5F-MDMB-PICA and MDMB-4en-PINACA; furthermore, 10 new substances not initially covered by LC-MS/MS analysis were detected by LC-qTOF/MS. The SC positivity rate was comparable to cocaine (5.4%) and amphetamine (2.6%). Only in 35 cases (0.7%), SC analysis was requested by the clients, highlighting the insufficient coverage of SC consumption in the studied collective. In summary, hair sample analysis proved to be a valuable tool to monitor the use of SCs. In order to keep pace with newly emerging SC analogs, an up-to-date analytical method is essential. Prospectively, SCs should be more routinely screened in hair analysis for abstinence control to avoid cannabis substitution by SCs.

The Basic Science of Cannabinoids

The cannabis plant has been used for centuries to manage the symptoms of various ailments including pain. Hundreds of chemical compounds have been identified and isolated from the plant and elicit a variety of physiological responses by binding to specific receptors and interacting with numerous other proteins. In addition, the body makes its own cannabinoid-like compounds that are integrally involved in modulating normal and pathophysiological processes. As the legal cannabis landscape continues to evolve within the United States and throughout the world, it is important to understand the rich science behind the effects of the plant and the implications for providers and patients. This narrative review aims to provide an overview of the basic science of the cannabinoids by describing the discovery and function of the endocannabinoid system, pharmacology of cannabinoids, and areas for future research and therapeutic development as they relate to perioperative and chronic pain medicine.

Synthetic Pathways to Non-Psychotropic Phytocannabinoids as Promising Molecules to Develop Novel Antibiotics: A Review

Due to the rapid emergence of multi drug resistant (MDR) pathogens against which current antibiotics are no longer functioning, severe infections are becoming practically untreatable. Consequently, the discovery of new classes of effective antimicrobial agents with novel mechanism of action is becoming increasingly urgent. The bioactivity of Cannabis sativa, an herbaceous plant used for millennia for medicinal and recreational purposes, is mainly due to its content in phytocannabinoids (PCs). Among the 180 PCs detected, cannabidiol (CBD), Δ⁸ and Δ⁹-tetrahydrocannabinols (Δ⁸-THC and Δ⁹-THC), cannabichromene (CBC), cannabigerol (CBG), cannabinol (CBN) and some of their acidic precursors have demonstrated from moderate to potent antibacterial effects against Gram-positive bacteria (MICs 0.5-8 µg/mL), including methicillin-resistant Staphylococcus aureus (MRSA), epidemic MRSA (EMRSA), as well as fluoroquinolone and tetracycline-resistant strains. Particularly, the non-psychotropic CBG was also capable to inhibit MRSA biofilm formation, to eradicate even mature biofilms, and to rapidly eliminate MRSA persiter cells. In this scenario, CBG, as well as other minor non-psychotropic PCs, such as CBD, and CBC could represent promising compounds for developing novel antibiotics with high therapeutic potential. Anyway, further studies are necessary, needing abundant quantities of such PCs, scarcely provided naturally by Cannabis plants. Here, after an extensive overture on cannabinoids including their reported antimicrobial effects, aiming at easing the synthetic production of the necessary amounts of CBG, CBC and CBD for further studies, we have, for the first time, systematically reviewed the synthetic pathways utilized for their synthesis, reporting both reaction schemes and experimental details.

Benzydamine-An Affordable Over-the-Counter Drug with Psychoactive Properties-From Chemical Structure to Possible Pharmacological Properties

Benzydamine is a non-steroidal anti-inflammatory drug with distinct pharmacological properties from other compounds in the same therapeutic class. The differences are structural and pharmacological in nature; the anti-inflammatory mechanism is not strictly explained by the ability to interfere with the synthesis of prostaglandins. The compound is used strictly in local inflammatory diseases (inflammation in the oral and vaginal mucosa). In addition to the therapeutic indications found in the summary of product characteristics (SPC), the compound is used, in high doses, as a psychotropic substance for oral administration, having similar properties to lysergic acid diethylamide (LSD). As an over-the-counter (OTC) compound, it is easy to obtain, and the consequences of using it for purposes other than those assumed by the manufacturer raise various concerns. The reasons are related to the pharmacodynamic and pharmaco-toxicological properties, since neither the mechanism of action nor the possible side effects that would result from systemic consumption, in high doses, even occasionally, have been fully elucidated. The present review aims to analyze the pharmacodynamic properties of benzydamine, starting from the chemical structure, by comparison with structurally similar compounds registered in therapy (as an anti-inflammatory or analgesic) or used for recreational purposes.

Base-mediated chalcogenoaminative annulation of 2-alkynylanilines for direct access to 3-sulfenyl/selenyl-1H-indoles

An efficient and transition metal-free synthesis of 3-sulfenyl/selenyl-1H-indoles via a base-assisted chalcogenoaminative annulation of 2-alkynyl aniline with disulfides/diselenides is described. A series of 2-alkynylanilines were found compatible with dichalcogenides in this transformation providing 3-sulfenyl/selenyl-1H-indoles in good to excellent yields. The presented methodology has the advantages of easily available raw materials, functional group tolerance, and a wide range of substrates that provide access to 3-sulfenylindoles and 3-selenylindoles.

Cytotoxicity associated with acute and chronic administration of synthetic cannabinoids “Strox” in the brain, liver, heart, and testes of male albino rats: histological and immunohistochemical study

Background

Synthetic cannabinoids are one of the largest groups of new psychoactive substances that invaded Egypt’s drug abuse market over the past few years.

Aim

Randomized controlled trial study to demonstrate the effects of acute and chronic toxicity by synthetic cannabinoid (Strox) on the brain, liver, heart, and testes in adult male albino rats through histopathological examination by light microscope and immunohistochemistry.

Methods

Total number of fifty male albino rats were divided into five different groups, two control and three treated groups. Negative and positive control groups received distilled water and dimethyl sulfoxide, respectively, acute group received LD50 (lethal dose 50) once and observed for 14 days, chronic group received 1/10 LD50 for 3 months, and finally chronic withdrawal groups received 1/10 LD50 for 3 months and then left 2 weeks without the substance to observe the withdrawal manifestations.

Results

The current study revealed various histopathological changes in all organs with increased expression of cannabinoid receptor 1. The most important findings observed by light microscope examination were shrinkage and degenerative changes in Purkinje cells in brain sections, abnormalities in blood sinusoids and architecture in liver section, disruption in cardiac muscle fiber in heart sections, and finally testes showed irregularities in seminiferous tubules and germinal cells. Immunohistochemical staining for caspase-3 in the brain, liver, and heart showed weak-positive reaction in acute group and a strong reaction with chronic groups. Additionally, increase in collagen fiber was observed in sections of the liver and heart of chronic group.

Conclusions

Synthetic cannabinoid sample (Strox) toxicity caused adverse effects on the brain, liver, heart, and testes as shown by increasing cannabinoid receptor 1 and caspase-3 expression.

Effects of cannabinoids on ligand-gated ion channels

Phytocannabinoids such as Δ⁹-tetrahydrocannabinol and cannabidiol, endocannabinoids such as N-arachidonoylethanolamine (anandamide) and 2-arachidonoylglycerol, and synthetic cannabinoids such as CP47,497 and JWH-018 constitute major groups of structurally diverse cannabinoids. Along with these cannabinoids, CB1 and CB2 cannabinoid receptors and enzymes involved in synthesis and degradation of endocannabinoids comprise the major components of the cannabinoid system. Although, cannabinoid receptors are known to be involved in anti-convulsant, anti-nociceptive, anti-psychotic, anti-emetic, and anti-oxidant effects of cannabinoids, in recent years, an increasing number of studies suggest that, at pharmacologically relevant concentrations, these compounds interact with several molecular targets including G-protein coupled receptors, ion channels, and enzymes in a cannabinoid-receptor independent manner. In this report, the direct actions of endo-, phyto-, and synthetic cannabinoids on the functional properties of ligand-gated ion channels and the plausible mechanisms mediating these effects were reviewed and discussed.

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.

Tribute to Professor Raphael Mechoulam, The Founder of Cannabinoid and Endocannabinoid Research

During the last 60 years the relevance for human health and disease of cannabis (Cannabis sativa or Cannabis indica) ingredients, like the psychoactive compound Δ9-tetrahydrocannabinol (THC), cannabidiol, 120+ cannabinoids and 440+ non-cannabinoid compounds, has become apparent [...].