Cannabinoid Analogues Research Articles

Novel fluorinated cannabinoid analogs modulate cytokine expression in human C20 microglial cells.

Phytochemicals derived from the plant Cannabis sativa hold promise in terms of medicinal value. Cannabinoids such as Δ9-tetrahydrocannabinol (THC), cannabidiol (CBD), and cannabinol (CBN) are arguably the best characterized and known to possess wide-ranging therapeutic benefits. The mechanism of action for these therapeutic effects remains to be fully elucidated, however, the anti-inflammatory actions are of particular interest. Maximizing therapeutic effects while limiting adverse effects is crucial in pharmaceutical development. Fluorination of natural products often yields molecules with enhanced biological properties and provides opportunities for intellectual property protection not available to the natural product. Herein, we describe four novel cannabinoids (a deoxy trifluoroCBN analog (F3CBN), the racemic cis-deoxy-trifluoro-THC (F3THC), and truncated pyridine analogs of an intermediate in route to the THC and CBN, SG126 and SG154. Importantly, we provide the initial assessment of the biologic activity of these molecules, by investigating the in vitro effects on metabolic activity (via 3-[4,5-dimethylthiazol-2-yl]-2,5,-diphenyltetrazolium bromide, MTT assay) and cytokine expression (via enzyme linked immunosorbent assay, ELISA) in human C20 microglial cells. The cannabinoids examined had minimal to no effect on metabolic activity up to 10µM. Notably, F3CBN and F3THC potentiated interleukin-1 β (IL-1β)-induced expression of interferon-γ inducible protein 10 (CXCL10) and IL-6 expression whereas, SG126 and SG154 were inhibitory. These findings are foundational for new lines of investigation into the therapeutic potential of four novel fluorinated cannabinoids.

A Novel tetrahydrocannabinol (THC) analog, 3,10,10-Trimethyl-1,2,3,4,4a,6,7,8,10,10a-decahydro-9-oxa-5-phenanthrenone (TDP), mitigates the decrease in cell viability in oxidatively-stressed osteosarcoma bone-like cell cultures, UMR 106-01 BSP (UMR cells)

Cannabinoids have been extensively studied in the field of cancer research. Tetrahydrocannabinol (THC) has shown promising results in influencing cellular proliferation and viability when used in association with other cannabinoids. However, not many studies have been done to explore the effect of THC analogs on osteosarcoma cells when used in concert with oxidative stressors like camptothecin (CPT). In this study, it was hypothesized that TDP would mitigate the oxidative effect of CPT on UMR cells. Briefly, synthesis of the novel THC analog, TDP, was attempted via a Knoevenagel condensation and a Diels-Alder reaction, using 1,3-cyclohexanediol dissolved in methanol and citronellal with ethylenediamine diacetic acid (EDDA) at a temperature of 60°C. UMR cells were routinely passaged, counted, plated in six-well culture plates at 480,000 cells/mL, then treated with 10-fold dilutions of TDP. The plates were incubated for 72 hours in a humidified incubator at 37 degrees Celsius with 5% carbon dioxide infusion. At the end of the experiment, the cells were routinely washed with HANKS buffered saline solution (HBSS), then counted using the Luna II Automated Cell Counter. In another experiment, designated cells were treated with different concentrations of CPT alone, while others were co-treated with different concentrations of TDP+CPT, following the protocol above. F test ANOVA was used to compare variances and all values in the results were expressed as means ± SD. The results from the attempted cannabinoid analog synthesis yielded an active novel THC analog, TDP. Serial dilutions treatment of the UMR cells with TDP alone showed its ability to decrease cell viability in a concentration-dependent manner. The treatment of the UMR cells with different concentrations of CPT alone resulted in a decrease in cell viability in a concentration-dependent manner. Co-treatment of the UMR cells with different concentrations of CPT+TDP showed that TDP was able to mitigate the effect of the oxidative stressor (CPT) on the UMR cell cultures. Moreover, the F Test ANOVA showed robust statistical significance (p values <0.05) regarding TDP’s ability to decrease the oxidative effect of CPT on UMR cells. Overall, the outcomes of this study suggest that active forms of THC analogs can be synthesized and tested in concert with oxidative stressors like CPT. This study opens the door to explore the mechanisms by which TDP exerts its effect on oxidatively-stressed cells and how it can possibly be used to prevent or mitigate the effect of oxidative stress on a variety of cells in culture. Moreover, the hopes of suggesting therapeutic uses of THC analogs, upon future mechanistic experimentations, is a goal. La Sierra University Title V Grant. This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

LC-MS/MS analysis of 11-nor-9-carboxy-hexahydrocannabinol (HHC-COOH) and 11-hydroxy-hexahydrocannabinol (HHC-OH) for verification of hexahydrocannabinol (HHC) intake

Natural and semi-synthetic cannabinoid analogs are getting increasing media attention for their recreative use as an alternative to traditional cannabis, in Sweden as well as internationally. To investigate an increasing number of urine samples incoming to our clinical laboratory that were screening positive, using a CEDIA THC-COOH immunoassay from ThermoFisher Scientific, but then testing negative using GC-MS based verification analysis, we developed an LC-MS/MS-method for verification of hexahydrocannabinol (HHC) and Δ8-tetrahydrocannabinol. Assessment of HHC intake was based on identification of the following four metabolites: 11-nor-9(R)-carboxy-hexahydrocannabinol (R-HHC-COOH), 11-nor-9(S)-carboxy-hexahydrocannabinol (S-HHC-COOH), 11-hydroxy-9(R)-hexahydrocannabinol (R-HHC-OH) and 11-hydroxy-9(S)-hexahydrocannabinol (S-HHC-OH). Out of 46 urine samples analysed in this study, 44 showed presence of HHC-metabolites, which indicate HHC as the main explanation for an increased number of negative verifications for THC-COOH. In these samples, the HHC-OH metabolites occurred at a higher concentration than R-HHC-COOH while S-HHC-COOH was only detected in few samples at low concentrations. R-HHC-COOH and S-HHC-COOH can easily be added to a pre-existing verification method for THC-COOH, and still show acceptable results, while HHC-OH requires an enzyme capable of hydrolysing the ether glucuronide bond.

Saturated Cannabinoids: Update on Synthesis Strategies and Biological Studies of These Emerging Cannabinoid Analogs.

Natural and non-natural hexahydrocannabinols (HHC) were first described in 1940 by Adam and in late 2021 arose on the drug market in the United States and in some European countries. A background on the discovery, synthesis, and pharmacology studies of hydrogenated and saturated cannabinoids is described. This is harmonized with a summary and comparison of the cannabinoid receptor affinities of various classical, hybrid, and non-classical saturated cannabinoids. A discussion of structure-activity relationships with the four different pharmacophores found in the cannabinoid scaffold is added to this review. According to laboratory studies in vitro, and in several animal species in vivo, HHC is reported to have broadly similar effects to Δ9-tetrahydrocannabinol (Δ9-THC), the main psychoactive substance in cannabis, as demonstrated both in vitro and in several animal species in vivo. However, the effects of HHC treatment have not been studied in humans, and thus a biological profile has not been established.

The Preanalytical Stability of Emerging Cannabinoid Analogs (Delta-8 THC and its Metabolites, Delta-10 THC, and Carboxy-HHC) in Urine.

There has been a surge in the presence and use of cannabinoids since the federal legalization of hemp (Agricultural Improvement Act of 2018). This increase is attributed not only to the use of ∆9-tetrahydrocannabinol (∆9-THC) and cannabidiol (CBD), the most abundant phytocannabinoid components of cannabis and hemp, respectively, but with the use of many other emerging THC analogs. Structurally, these analogs are similar to ∆9-THC. Urine specimens for drug analysis are often collected offsite and transported to a laboratory for analysis. Screening assays are usually the first step in urine drug testing. These assays are usually qualitative and automated, which for negative specimens, reduces cost and reporting time. The stability of ∆9-THC and its metabolites has been known for some time, however the stability of emerging analogs has not been elucidated, therefore assuming equivalent storage stability can be erroneous. Previous work assessed the cross-reactivity of ∆8-THC and its major metabolites, the ∆1°-THC chiral analogs, and the chiral 11-COOH-HHC analogs. Stability was assessed for each analyte at a concentration two times greater than the analytes determined decision point. Samples were prepared in drug-free urine at three different pHs (4.5, 7, and 9) and stored at three different temperatures (4°C, 20°C, and 45°C) in triplicate. Samples were analyzed utilizing the LZI Cannabinoids (cTHC) Enzyme Immunoassay cannabinoid screening kit calibrated at the 25 ng/mL cutoff. Overall, the cannabinoid analogs produced diminishing instrument responses depending on pH and temperature. The parent analogs were not detected after a single day at 45°C regardless of pH. In general, carboxylic acid analogs at the acidic pH (4.5) produced diminished instrument responses when compared to their counterparts stored at neutral (7) and basic (9) pH. The time, storage temperature, and pH of urine specimens may affect the screening results of specimens collected for cannabinoid drug screening.

The Cross Reactivity of Cannabinoid Analogs (Delta-8-THC, Delta-10-THC and CBD), their metabolites, and Chiral Carboxy HHC metabolites in Urine of Six Commercially Available Homogeneous Immunoassays.

There has been an exponential surge in the presence and use of cannabinoids since the federal legalization of hemp (Agricultural Improvement Act of 2018). This growth is attributed to Delta-9-tetrahydrocannabinol (Delta-9-THC) and cannabidiol (CBD), the most abundant phytocannabinoid components of cannabis and hemp, respectively, but with many other emerging THC analogs. Structurally, these analogs are similar to Delta-9-THC, yet very little information is available about their potency and even less information is available regarding their detectability using commercially available cannabinoid screening kits. Due to their structural similarity, current cannabinoid homogeneous immunoassay screening methods may be able to detect these emerging cannabinoid analogs and their metabolites. Six urine immunoassay kits (Abbott Cannabinoids - Abbott Diagnostics, LZI Cannabinoids (cTHC) Enzyme Immunoassay - Lin-Zhi International, DRI® Cannabinoid Assay and CEDIA™ THC - Thermo Fisher Scientific, ONLINE DAT Cannabinoid II - Roche Diagnostics, and Syva EMIT®II Plus - Siemens Healthineers) were evaluated at two different cutoff concentrations: 50ng/mL and 20 or 25ng/mL, assay dependent. The analysis was performed on an Abbott Architect Plus c4000 (Abbott Diagnostics). Delta-8-THC, CBD, olivetol and their major metabolites, and Delta-10-THC and HHC carboxylic acid chiral analogs were evaluated. The cross reactivity was evaluated by preparing each analyte at 20, 50, 100, and 1000ng/mL in urine. Analytes that did not cross react at 1000ng/mL for a cutoff were considered not detectable. If detected, the lowest concentration was used as the decision point to determine the precision at the immunoassay's cutoff. The six commercially available urine cannabinoid homogeneous immunoassay screening kits cross reacted with the following analogs: Delta-8-THC, 11-OH-Delta-8-THC, 11-COOH-Delta-8-THC, 6-OH-CBD, 7-OH-CBD, all Delta-10-THC and HHC carboxylic acid chiral analogs, and olivetol with varying selectivity depending on the screening kit and cutoff concentration. The kits did not cross react with the following analogs: CBD, 7-COOH-CBD, Abnormal CBD, CBDA-A, and olivetolic acid.

A comprehensive analytical strategy based on characteristic fragments to detect synthetic cannabinoid analogs in seized products and hair samples

Synthetic cannabinoids, one of the most widely abused new psychoactive substances (NPS), are now placed under national control generally in China. Due to continuous modification of synthetic cannabinoid structure, an ongoing dilemma in the forensic laboratory is that newly emerging substances cannot be detected by established methods. Thus, the screening methods for simultaneous detection of known or unknown substances have become research hotspots. In this study, the ultra high performance liquid chromatography tandem triple quadrupole mass spectrometry (UPLC-QqQ-MS) with precursor ion scan (PIS) as acquisition mode was used for prescreening purposes of all possible synthetic cannabinoids-related substances. In detail, four common characteristic fragments, m/z of 144.0, 145.0, 135.1, and 109.0 corresponding to acylium-indole, acylium-indazole, adamantyl, and fluorobenzyl cation respectively, were selected for PIS mode, and their collision energies were optimized by 97 available synthetic cannabinoids standards with relevant structures. Those suspicious signals observed in the screening experiment were confirmed by ultra high performance liquid chromatography tandem quadrupole time-of-flight mass spectrometry (UPLC-QTOF-MS) via high-resolution MS and MS2 data obtained by full scan (TOF MS) and product ion scan mode. After methodological validation, the integrated strategy established above was applied to the screening and identification of the seized e-liquids, herbal blends and hair samples, confirming the presence of multiple synthetic cannabinoids in these samples. In particular, a novel synthetic cannabinoid was identified as 4 F-ABUTINACA, for which no relevant high-resolution mass spectrometry (HRMS) data has been retrieved until now, making this study the first to report the cleavage pattern of this compound in electrospray ionization (ESI) mass spectrometry. In addition, four other suspected by-products of the synthetic cannabinoids were found in the herbal blends and e-liquids, and their possible structures were also deduced via the information from high-resolution mass spectra.

Enantioselective Total Synthesis of Cannabinoids via a Tandem Conjugate Addition/Enolate Alkylation Annulation with Ambiphilic Organoboronates

Cannabinoid research depends on synthesizing derivatives for structure-activity relationship studies. (-)-Δ9-Tetrahydrocannabinol and cannabidiol were synthesized via a tandem enantioselective conjugate addition/enolate alkylation annulation with a novel ambiphilic trifluoroborate in seven steps. A new class of alkenyl and aryl ambiphilic trifluoroborates were synthesized and showed great compatibility with various functional groups, high yields, and excellent enantio- and diastereoselectivity. A novel benzo-fused cannabinoid analogue and tandem quaternary stereocenter-containing reaction products were synthesized with good to excellent enantioselectivity.

Identification of a novel bromoindazole synthetic cannabinoid analogue in seized e-cigarette liquid: ADB-BRINACA

A wide variety of new synthetic cannabinoids have emerged around the world in recent years, and because of this rapid emergence, the detection and monitoring of this class of abused drugs remain a challenge. In this study, a new cannabimimetic indazole-3-carboxamide derivative, N-(1-amino-3,3-dimethyl-1-oxobutan-2-yl)− 5-bromo-1 H-indazole-3-carboxamide, was identified from seized e-cigarette liquid samples and newly named as ADB-BRINACA by referring to the names of other known indazole-class synthetic cannabinoids. Structure identification was accomplished based on gas chromatography-mass spectrometry (GC-MS), high-performance liquid chromatography-high resolution quadrupole mass spectrometry (HPLC-QTOF-MS/MS), and nuclear magnetic resonance spectrometry (NMR). The concentration range of ADB-BRINACA in six e-cigarette liquid samples was found to be 2228–4203 mg/L using ERETIC 2, a quantitative NMR method, which is advantageous in the absence of a reference material. As there have been no chemical or pharmaceutical reports on ADB-BRINACA until now, this is the first report presenting a comprehensive analytical characterization of ADB-BRINACA.

Synthesis of A Tetrahydrocannabinol (THC) Analog For Analyzing Cellular Proliferation in Concert With Epigallocatechin Gallate (EGCG) on A Bone‐like Cancer Cell Line (UMR 106‐01 BSP)

Cannabinoids have been extensively studied in the field of cancer research. Tetrahydrocannabinol (THC) has shown promising results in influencing cellular proliferation when in association with other cannabinoids. This traditional entourage effect solely focuses on the study of THC with other cannabinoids. However, not many studies have been done to explore the synergistic effect of THC analogs when used with non‐cannabinoid compounds. THC in its isolate form for experimentation is very strictly regulated. Therefore, this study was conducted in the pursuit of synthesizing and experimenting with analogs of THC to observe a potential entourage effect with epigallocatechin gallate (EGCG), a compound known for its efficacy to reduce proliferation at higher concentrations in UMR cells. It was hypothesized that active analogs of THC can be synthesized and used in concert with EGCG to potentiate decreased proliferation in the bone‐like cancer cell line UMR 106‐01 BSP (UMR cells). Briefly, a Knoevenagel condensation and a Diels‐Alder reaction using 1,3‐cyclohexanediol dissolved in methanol (MeOH) and citronellal with ethylenediamine diacetic acid (EDDA) at a temperature of 60℃ was used to synthesize a novel THC analog, 3,10,10‐Trimethyl‐1,2,3,4,4a,6,7,8,10,10a‐decahydro‐9‐oxa‐5‐phenanthrenone (TDP). UMR cells were routinely passaged, counted, plated in six‐well culture plates at 480,00 cells/mL, then treated with 10‐fold dilutions of TDP. The plates were incubated for 72 hours in a humidified incubator at 37 degrees Celsius with 5% carbon dioxide infusion. At the end of the experiment, the cells were routinely washed with HANKS buffered saline solution (HBSS), then routinely counted using the Luna Automated Cell Counter. In another experiment, designated cells were co‐treated with TDP+EGCG, following the protocol above. F test ANOVA was used to compare variances and all values in the results were expressed as means ± SD. The results from the attempted cannabinoid analog synthesis yielded a novel active THC analog, TDP. Serial dilutions treatment of the UMR cells with TDP alone showed its ability to decrease cell count in a concentration dependent manner. However, when coupled with higher concentrations of EGCG, the co‐treatment increased cell count rather than potentiating the effect of decreasing cellular proliferation. The F Test ANOVA showed robust statistical significance (p values <0.05) with regard to TDP’s effect of decreasing cell proliferation in UMR cells in a concentration‐dependent manner. Overall, the outcomes of this study suggest that active forms of THC analogs can be synthesized and tested in concert with other non‐cannabinoid compounds like EGCG. This study opens the door to explore the entourage effect of TDP with other non‐cannabinoid compounds that may provide another tool in the therapeutic treatment of bone cancer cells.

Roles of the Cannabinoid System in the Basal Ganglia in Parkinson's Disease.

Parkinson’s disease (PD) is a neurodegenerative disease usually caused by neuroinflammation, oxidative stress and other etiologies. Recent studies have found that the cannabinoid system present in the basal ganglia has a strong influence on the progression of PD. Altering the cannabinoid receptor activation status by modulating endogenous cannabinoid (eCB) levels can exert an anti-movement disorder effect. Therefore, the development of drugs that modulate the endocannabinoid system may be a novel strategy for the treatment of PD. However, eCB regulation is complex, with diverse cannabinoid receptor functions and the presence of dopaminergic, glutamatergic, and γ-aminobutyric signals interacting with cannabinoid signaling in the basal ganglia region. Therefore, the study of eCB is challenging. Here, we have described the function of the cannabinoid system in the basal ganglia and its association with PD in three parts (eCBs, cannabinoid receptors, and factors regulating the cannabinoid metabolism) and summarized the mechanisms of action related to the cannabinoid analogs currently aimed at treating PD. The shortcomings identified from previous studies and the directions that should be explored in the future will provide insights into new approaches and ideas for the future development of cannabinoid-based drugs and the treatment of PD.

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.

Virtual screening using docking and molecular dynamics of cannabinoid analogs against CB1 and CB2 receptors

BackgroundCannabis sativa has been attributed to different pharmacological properties. A number of secondary metabolites such as tetrahydrocannabinol (THC), cannabinol (CBD), and different analogs, with highly promising biological activity on CB1 and CB2 receptors, have been identified. MethodsThus, this study aimed was to evaluate the activity of THC, CBD, and their analogs using molecular docking and molecular dynamics simulations (MD) methods. Initially, the molecules (ligands) were selected by bioinformatics searches in databases. Subsequently, CB1 and CB2 receptors were retrieved from the protein data bank database. Afterward, each receptor and its ligands were optimized to perform molecular docking. Then, MD Simulation was performed with the most stable ligand-receptor complexes. Finally, the Molecular Mechanics-Generalized Born Surface Area (MM-PBSA) method was applied to analyze the binding free energy between ligands and cannabinoid receptors. ResultsThe results obtained showed that ligand LS-61176 presented the best affinity in the molecular docking analysis. Also, this analog could be a CB1 negative allosteric modulator like CBD and probably an agonist in CB2 like THC and CBD according to their dynamic behavior in silico. The possibility of having a THC and a CBD analog (LS-61176) as a promising molecule for experimental evaluation since it could have no central side-effects on CB1 and have effects of CB2 useful in pain, inflammation, and some immunological disorders. Docking results were validate using ROC curve for both cannabinoids receptor where AUC for CB1 receptor was 0.894±0.024, and for CB2 receptor AUC was 0.832±0032, indicating good affinity prediction.

The CB2 Receptor as a Novel Therapeutic Target for Epilepsy Treatment.

Epilepsy is characterized by repeated spontaneous bursts of neuronal hyperactivity and high synchronization in the central nervous system. It seriously affects the quality of life of epileptic patients, and nearly 30% of individuals are refractory to treatment of antiseizure drugs. Therefore, there is an urgent need to develop new drugs to manage and control refractory epilepsy. Cannabinoid ligands, including selective cannabinoid receptor subtype (CB1 or CB2 receptor) ligands and non-selective cannabinoid (synthetic and endogenous) ligands, may serve as novel candidates for this need. Cannabinoid appears to regulate seizure activity in the brain through the activation of CB1 and CB2 cannabinoid receptors (CB1R and CB2R). An abundant series of cannabinoid analogues have been tested in various animal models, including the rat pilocarpine model of acquired epilepsy, a pentylenetetrazol model of myoclonic seizures in mice, and a penicillin-induced model of epileptiform activity in the rats. The accumulating lines of evidence show that cannabinoid ligands exhibit significant benefits to control seizure activity in different epileptic models. In this review, we summarize the relationship between brain CB2 receptors and seizures and emphasize the potential mechanisms of their therapeutic effects involving the influences of neurons, astrocytes, and microglia cells. The unique features of CB2Rs, such as lower expression levels under physiological conditions and high inducibility under epileptic conditions, make it an important target for future research on drug-resistant epilepsy.

Cannabinoid WIN 55,212-2 Inhibits Human Glioma Cell Growth by Triggering ROS-Mediated Signal Pathways.

Glioblastoma is a highly invasive primary malignant tumor of the central nervous system. Cannabinoid analogue WIN 55,212-2 (WIN) exhibited a novel anticancer effect against human tumors. However, the anticancer potential and underlying mechanism of WIN against human glioma remain unclear. Herein, the anticancer efficiency and mechanism of WIN in U251 human glioma cells were investigated. The results showed that WIN dose-dependently inhibited U251 cell proliferation, migration, and invasion in vitro. WIN treatment also effectively suppressed U251 tumor spheroids growth ex vivo. Further studies found that WIN induced significant apoptosis as convinced by the caspase-3 activation and release of cytochrome C. Mechanism investigation revealed that WIN triggered ROS-mediated DNA damage and caused dysfunction of VEGF-AKT/FAK signal axis. However, ROS inhibition effectively attenuated WIN-induced DNA damage and dysfunction of VEGF-AKT/FAK signal axis and eventually improved U251 cell proliferation, migration, and invasion. Taken together, our findings validated that WIN had the potential to inhibit U251 cell proliferation, migration, and invasion and induce apoptosis by triggering ROS-dependent DNA damage and dysfunction of VEGF-AKT/FAK signal axis.

Spinal astroglial cannabinoid receptors control pathological tremor.

Cannabinoids reduce tremor associated with motor disorders induced by injuries and neurodegenerative disease. Here we show that this effect is mediated by cannabinoid receptors on astrocytes in the ventral horn of the spinal cord, where alternating limb movements are initiated. We first demonstrate that tremor is reduced in a mouse model of essential tremor after intrathecal injection of the cannabinoid analog WIN55,212-2. We investigate the underlying mechanism using electrophysiological recordings in spinal cord slices and show that endocannabinoids released from depolarized interneurons activate astrocytic cannabinoid receptors, causing an increase in intracellular Ca2+, subsequent release of purines, and inhibition of excitatory neurotransmission. Finally, we show that the anti-tremor action of WIN55,212-2 in the spinal cords of mice is suppressed after knocking out CB1 receptors in astrocytes. Our data suggest that cannabinoids reduce tremor via their action on spinal astrocytes.

Analogues of cannabinoids as multitarget drugs in the treatment of Alzheimer's disease

Given that neuronal degeneration in Alzheimer's disease (AD) is caused by the combination of multiple neurotoxic insults, current directions in the research of novel therapies to treat this disease attempts to design multitarget strategies that could be more effective than the simply use of acetylcholinesterase inhibitors; currently, the most used therapy for AD. One option, explored recently, is the synthesis of new analogues of cannabinoids that could competitively inhibit the acetylcholinesterase (AChE) enzyme and showing the classic neuroprotective profile of cannabinoid compounds. In this work, molecular docking has been used to design some cannabinoid analogues with such multitarget properties, based on the similarities of donepezil and Δ9-tetrahydrocannabinol. The analogues synthesized, compounds 1 and 2, demonstrated to have two interesting characteristics in different in vitro assays: competitive inhibition of AChE and competitive antagonism at the CB1/CB2 receptors. They are highly lipophilic, highlighting that they could easily reach the CNS, and apparently presented a low toxicity. These results open the door to the synthesis of new compounds for a more effective treatment of AD.

Molecular Mechanisms for the Inflammation-Resolving Actions of Lenabasum

A first-in-class cannabinoid analog called lenabasum that is a CB2 agonist is being developed as an inflammation-resolving drug candidate. Thus far, specific therapeutic targets include scleroderma, cystic fibrosis, dermatomyositis, and lupus, all of which represent unmet medical needs. Two somewhat-independent molecular mechanisms for this type of action are here proposed. Both pathways initially involve the release of free arachidonic acid after activation of the CB2 receptor and phospholipase A2 by lenabasum. The pathways then diverge into a cyclooxygenase 2-mediated and a lipoxygenase-mediated route. The former leads to increased levels of the cyclopentenone prostaglandin 15-deoxy-Δ12,14-prostaglandin-J2 that can activate the NLPR3 inflammasome, which in turn releases caspase-3, leading to apoptosis and the resolution of chronic inflammation. The lipoxygenase-mediated pathway stimulates the production of lipoxin A4 as well as other signaling molecules called specialized proresolving mediators. These also have inflammation-resolving actions. It is not well understood under which conditions each of these mechanisms operates and whether there is crosstalk between them. Thus, much remains to be learned about the mechanisms describing the actions of lenabasum. SIGNIFICANCE STATEMENT: The resolution of chronic inflammation is a major unmet medical need. The synthetic nonpsychoactive cannabinoid lenabasum could provide a safe and effective drug for this purpose. Two putative molecular mechanisms are suggested to better understand how lenabasum produces this action. In both, different metabolites of arachidonic acid act as mediators.

Cannabinoid as Potential Aromatase Inhibitor Through Molecular Modeling and Screening for Anti-Cancer Activity

Inhibition of aromatase (CYTP450), a key enzyme in the estrogen biosynthesis, could result in regression of estrogen-dependent tumors and even prevent the promotion of breast cancer. The present research has been designed for searching a potent chemical moiety from natural sources to inhibit aromatase enzyme, the overfunctionality of which causes the breast cancer. Cannabis sativa contains a very much promising group of cannabinoids with more than 66 compounds with reported anticancer property and for the search of a target specific potent aromatase inhibitor, 61 cannabinoids from C. sativa were selected. The Structures Data File (SDF) of these ligand molecules were subjected to docking studies at the binding site of aromatase X-ray crystallographic structure based on lower resolution of the protein crystal structure and higher docking accuracy, predicted by calculating the correlation between experimental activities and Glide dock scores and compared with the standard aromatase ligand androstenedione and aromatase inhibitor fadrozole with existing drug for breast cancer treatment. The best docked pose of each ligand was selected on the basis of the highest dock score related to the binding free energies of the internal dataset compounds as compared to their observed activities. Apart from the hydrogen bond formation with the oxygen present on the aromatic ring system, the other parts of the molecules are stabilized by hydrophobic interactions with non-polar amino acid residues (Ile133, Phe134, Phe221, Trp224, Ile305, Ala306, Ala307, Val369, Val370, Leu372, Val373, Met374 and Leu477). From the screening results of the cannabinoid analogs, 21 out of 61 were found to have an acceptable docking score in comparison to the standards, androstenedione and fadrozole. The pharmacokinetic filters like absorption, distribution, metabolism and excretion and toxicity (ADMET) property determination were applied to select drug-like compounds. Among them three compounds were found to reveal the most promising drug like activity, which were cannabidiorcol (CN 17, CBD-C1), cannabitriol (CN 43, CBT) and cannabiripsol (CN 55, CBR). The ani-cancer activity of the target compounds was performed against brine shrimp lethality biassay, where cannabidiorcol exhibited significant LC50 value of 0.348 ±0.002 μg/ml (R² = 0.9853) which is almost similar to vincristine sulfate (LC50 = 0.316±0.003 μg/ml, R² = 0.9882). Compound cannabitriol also showed promisimg cytotoxicity 0.650±0.004 μg/ml (R² = 0.9882) in comparison to the reference standard. But cannabiripsol demostrated relatively weaker activity 12.95±1.234 μg/ml (R²=0.9897). It can be concluded that the lead compounds may be developed as potent aromatase inhibitor performing their further biological evaluation.
 Dhaka Univ. J. Pharm. Sci. 19(1): 47-58, 2020 (June)

Insight of druggable cannabinoids against estrogen receptor β in breast cancer

Breast cancer (BC) is the second most prevalent cancer worldwide. Estrogen receptor beta (ERβ) is an essential protein of breast cells to suppress estrogen-induced uncontrolled proliferation. Thus, small molecules that can modulate and enhance ERβ expression would be an effective agent to suppress BC development. Studies showed that cannabinoid (CB), specifically delta-9-tetrahydrocannabinol (Del9THC), can increase the expression of ERβ and inhibits BC cell proliferation. In this study, less psychoactive and structurally similar analogs of Del9THC were chosen as drug candidates and ERβ was targeted as a therapeutic receptor. Delta-8-tetrahydrocannabinol (Del8THC) and delta-4-isotetrahydrocannabinol (Del4isoTHC) were the drug candidates selected on the basis of literature reports, absorption, distribution, metabolism, excretion, and toxicity (ADMET) properties, medicinal chemistry profile, and physicochemical features. Molecular docking simulations were carried out to determine ligand receptor interactions and binding affinity based on free binding energy. To get a better drug, the structural modification was done on Del8THC and generated a new CB analog called Cannabinoid A. Finally, molecular interaction analysis revealed that two CBs and one of their analog interact with the active site residues of ERβ. Therefore, this study revealed a new way to discover novel drug(s) for BC patients. Communicated by Ramaswamy H. Sarma