Novel Insights into Cannabinoid Receptors, Molecular Targets, and Therapeutic Potentials

A topical collection in Cells (ISSN 2073-4409). This collection belongs to the section "Cell Signaling".

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Editor


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Collection Editor
Department of Pharmacology and Toxicology, University of Louisville School of Medicine, Louisville, KY 40292, USA
Interests: cannabinoid receptors; novel cannabinoid targets; cannabinoid signaling; cannabinoid therapeutic potentials

Topical Collection Information

Dear Colleagues,

Cannabis has been used as a remedy for illness for centuries in various cultures. Recently, there has been a renewed interest in the uses of cannabis and cannabinoids for medicinal purposes, due to improved legal status in medical cannabis and the advances in cannabinoid research. Cannabinoids are composed of three categories, including phytocannabinoids (the active chemical components of cannabis), endocannabinoids (the cannabinoid-like substances in our body), and synthetic cannabinoids (the cannabinoids prepared in the laboratory). Cannabinoids exert their effects through multiple receptors, targets and signaling pathways. In addition to CB1 and CB2, two well-established cannabinoid receptors, there are numerous molecular targets for cannabinoids, e.g., G-protein-coupled receptors (GPR55, GPR18, GPR3/GPR6/GPR12), transient receptor potential (TRPV) channels, and peroxisome proliferator-activated (PPAR) receptors. These cannabinoid receptors and molecular targets play essential roles for the effects of cannabinoids in health and disease. In addition, they are underscoring the mechanisms of actions for the potential therapeutic effects of a variety of cannabinoids. Recently, there have been tremendous advances in our understanding of these receptors and molecular targets, as well as their implications in the therapeutic potentials of cannabinoids.

The emphasis of this Topical Collection is on the recent advances in our knowledge of cannabinoid receptors, molecular targets, and signaling pathways in the context of physiological/pathological conditions, and cannabinoid therapeutic potentials. Review articles summarizing recent discoveries, and original research articles of both basic and clinical studies are welcome.

We look forward to your important contributions.

Dr. Zhao-Hui Song
Collection Editor

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Keywords

  • Cannabinoid receptor
  • Molecular target
  • Signal transduction
  • Therapeutic potentials

Published Papers (17 papers)

2024

Jump to: 2023, 2022

22 pages, 9581 KiB  
Article
Functional Selectivity of Cannabinoid Type 1 G Protein-Coupled Receptor Agonists in Transactivating Glycosylated Receptors on Cancer Cells to Induce Epithelial–Mesenchymal Transition Metastatic Phenotype
by David A. Bunsick, Jenna Matsukubo, Rashelle Aldbai, Leili Baghaie and Myron R. Szewczuk
Cells 2024, 13(6), 480; https://doi.org/10.3390/cells13060480 - 08 Mar 2024
Viewed by 727
Abstract
Understanding the role of biased G protein-coupled receptor (GPCR) agonism in receptor signaling may provide novel insights into the opposing effects mediated by cannabinoids, particularly in cancer and cancer metastasis. GPCRs can have more than one active state, a phenomenon called either ‘biased [...] Read more.
Understanding the role of biased G protein-coupled receptor (GPCR) agonism in receptor signaling may provide novel insights into the opposing effects mediated by cannabinoids, particularly in cancer and cancer metastasis. GPCRs can have more than one active state, a phenomenon called either ‘biased agonism’, ‘functional selectivity’, or ‘ligand-directed signaling’. However, there are increasing arrays of cannabinoid allosteric ligands with different degrees of modulation, called ‘biased modulation’, that can vary dramatically in a probe- and pathway-specific manner, not from simple differences in orthosteric ligand efficacy or stimulus-response coupling. Here, emerging evidence proposes the involvement of CB1 GPCRs in a novel biased GPCR signaling paradigm involving the crosstalk between neuraminidase-1 (Neu-1) and matrix metalloproteinase-9 (MMP-9) in the activation of glycosylated receptors through the modification of the receptor glycosylation state. The study findings highlighted the role of CB1 agonists AM-404, Aravnil, and Olvanil in significantly inducing Neu-1 sialidase activity in a dose-dependent fashion in RAW-Blue, PANC-1, and SW-620 cells. This approach was further substantiated by findings that the neuromedin B receptor inhibitor, BIM-23127, MMP-9 inhibitor, MMP9i, and Neu-1 inhibitor, oseltamivir phosphate, could specifically block CB1 agonist-induced Neu-1 sialidase activity. Additionally, we found that CB1 receptors exist in a multimeric receptor complex with Neu-1 in naïve, unstimulated RAW-Blue, PANC-1, and SW-620 cells. This complex implies a molecular link that regulates the interaction and signaling mechanism among these molecules present on the cell surface. Moreover, the study results demonstrate that CB1 agonists induce NFκB-dependent secretory alkaline phosphatase (SEAP) activity in influencing the expression of epithelial–mesenchymal markers, E-cadherin, and vimentin in SW-620 cells, albeit the impact on E-cadherin expression is less pronounced compared to vimentin. In essence, this innovative research begins to elucidate an entirely new molecular mechanism involving a GPCR signaling paradigm in which cannabinoids, as epigenetic stimuli, may traverse to influence gene expression and contribute to cancer and cancer metastasis. Full article
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17 pages, 2329 KiB  
Article
Evaluating the Mechanism of Cell Death in Melanoma Induced by the Cannabis Extract PHEC-66
by Ava Bachari, Nazim Nassar, Srinivasareddy Telukutla, Roby Zomer, Terrence J. Piva and Nitin Mantri
Cells 2024, 13(3), 268; https://doi.org/10.3390/cells13030268 - 31 Jan 2024
Viewed by 10346
Abstract
Research suggests the potential of using cannabinoid-derived compounds to function as anticancer agents against melanoma cells. Our recent study highlighted the remarkable in vitro anticancer effects of PHEC-66, an extract from Cannabis sativa, on the MM418-C1, MM329, and MM96L melanoma cell lines. [...] Read more.
Research suggests the potential of using cannabinoid-derived compounds to function as anticancer agents against melanoma cells. Our recent study highlighted the remarkable in vitro anticancer effects of PHEC-66, an extract from Cannabis sativa, on the MM418-C1, MM329, and MM96L melanoma cell lines. However, the complete molecular mechanism behind this action remains to be elucidated. This study aims to unravel how PHEC-66 brings about its antiproliferative impact on these cell lines, utilising diverse techniques such as real-time polymerase chain reaction (qPCR), assays to assess the inhibition of CB1 and CB2 receptors, measurement of reactive oxygen species (ROS), apoptosis assays, and fluorescence-activated cell sorting (FACS) for apoptosis and cell cycle analysis. The outcomes obtained from this study suggest that PHEC-66 triggers apoptosis in these melanoma cell lines by increasing the expression of pro-apoptotic markers (BAX mRNA) while concurrently reducing the expression of anti-apoptotic markers (Bcl-2 mRNA). Additionally, PHEC-66 induces DNA fragmentation, halting cell progression at the G1 cell cycle checkpoint and substantially elevating intracellular ROS levels. These findings imply that PHEC-66 might have potential as an adjuvant therapy in the treatment of malignant melanoma. However, it is essential to conduct further preclinical investigations to delve deeper into its potential and efficacy. Full article
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2023

Jump to: 2024, 2022

26 pages, 7248 KiB  
Article
Elucidation of GPR55-Associated Signaling behind THC and LPI Reducing Effects on Ki67-Immunoreactive Nuclei in Patient-Derived Glioblastoma Cells
by Marc Richard Kolbe, Tim Hohmann, Urszula Hohmann, Erik Maronde, Ralph Golbik, Julian Prell, Jörg Illert, Christian Strauss and Faramarz Dehghani
Cells 2023, 12(22), 2646; https://doi.org/10.3390/cells12222646 - 17 Nov 2023
Viewed by 997
Abstract
GPR55 is involved in many physiological and pathological processes. In cancer, GPR55 has been described to show accelerating and decelerating effects in tumor progression resulting from distinct intracellular signaling pathways. GPR55 becomes activated by LPI and various plant-derived, endogenous, and synthetic cannabinoids. Cannabinoids [...] Read more.
GPR55 is involved in many physiological and pathological processes. In cancer, GPR55 has been described to show accelerating and decelerating effects in tumor progression resulting from distinct intracellular signaling pathways. GPR55 becomes activated by LPI and various plant-derived, endogenous, and synthetic cannabinoids. Cannabinoids such as THC exerted antitumor effects by inhibiting tumor cell proliferation or inducing apoptosis. Besides its effects through CB1 and CB2 receptors, THC modulates cellular responses among others via GPR55. Previously, we reported a reduction in Ki67-immunoreactive nuclei of human glioblastoma cells after GPR55 activation in general by THC and in particular by LPI. In the present study, we investigated intracellular mechanisms leading to an altered number of Ki67+ nuclei after stimulation of GPR55 by LPI and THC. Pharmacological analyses revealed a strongly involved PLC-IP3 signaling and cell-type-specific differences in Gα-, Gβγ-, RhoA-ROCK, and calcineurin signaling. Furthermore, immunochemical visualization of the calcineurin-dependent transcription factor NFAT revealed an unchanged subcellular localization after THC or LPI treatment. The data underline the cell-type-specific diversity of GPR55-associated signaling pathways in coupling to intracellular G proteins. Furthermore, this diversity might determine the outcome and the individual responsiveness of tumor cells to GPR55 stimulation by cannabin oids. Full article
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17 pages, 3036 KiB  
Article
In Vitro Antiproliferative Effect of Cannabis Extract PHEC-66 on Melanoma Cell Lines
by Ava Bachari, Nazim Nassar, Srinivasareddy Telukutla, Roby Zomer, Chaitali Dekiwadia, Terrence J. Piva and Nitin Mantri
Cells 2023, 12(20), 2450; https://doi.org/10.3390/cells12202450 - 13 Oct 2023
Cited by 2 | Viewed by 1619
Abstract
Melanoma, an aggressive form of skin cancer, can be fatal if not diagnosed and treated early. Melanoma is widely recognized to resist advanced cancer treatments, including immune checkpoint inhibitors, kinase inhibitors, and chemotherapy. Numerous studies have shown that various Cannabis sativa extracts exhibit [...] Read more.
Melanoma, an aggressive form of skin cancer, can be fatal if not diagnosed and treated early. Melanoma is widely recognized to resist advanced cancer treatments, including immune checkpoint inhibitors, kinase inhibitors, and chemotherapy. Numerous studies have shown that various Cannabis sativa extracts exhibit potential anticancer effects against different types of tumours both in vitro and in vivo. This study is the first to report that PHEC-66, a Cannabis sativa extract, displays antiproliferative effects against MM418-C1, MM329 and MM96L melanoma cells. Although these findings suggest that PHEC-66 has promising potential as a pharmacotherapeutic agent for melanoma treatment, further research is necessary to evaluate its safety, efficacy, and clinical applications. Full article
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25 pages, 4722 KiB  
Article
Early Administration of the Phytocannabinoid Cannabidivarin Prevents the Neurobehavioral Abnormalities Associated with the Fmr1-KO Mouse Model of Fragile X Syndrome
by Marika Premoli, William Fyke, Luigi Bellocchio, Valerie Lemaire, Marie Wolley-Roberts, Bruno Bontempi and Susanna Pietropaolo
Cells 2023, 12(15), 1927; https://doi.org/10.3390/cells12151927 - 25 Jul 2023
Viewed by 1170
Abstract
Phytocannabinoids, including the non-addictive cannabis component cannabidivarin (CBDV), have been reported to hold therapeutic potential in several neurodevelopmental disorders (NDDs). Nonetheless, the therapeutic value of phytocannabinoids for treating Fragile X syndrome (FXS), a major NDD, remains unexplored. Here, we characterized the neurobehavioral effects [...] Read more.
Phytocannabinoids, including the non-addictive cannabis component cannabidivarin (CBDV), have been reported to hold therapeutic potential in several neurodevelopmental disorders (NDDs). Nonetheless, the therapeutic value of phytocannabinoids for treating Fragile X syndrome (FXS), a major NDD, remains unexplored. Here, we characterized the neurobehavioral effects of CBDV at doses of 20 or 100 mg/kg in the Fmr1-knockout (Fmr1-KO) mouse model of FXS using two temporally different intraperitoneal regimens: subchronic 10-day delivery during adulthood (Study 1: rescue treatment) or chronic 5-week delivery at adolescence (Study 2: preventive treatment). Behavioral tests assessing FXS-like abnormalities included anxiety, locomotor, cognitive, social and sensory alterations. Expression of inflammatory and plasticity markers was investigated in the hippocampus and prefrontal cortex. When administered during adulthood (Study 1), the effects of CBDV were marginal, rescuing at the lower dose only the acoustic hyper-responsiveness of Fmr1-KO mice and at both doses their altered hippocampal expression of neurotrophins. When administered during adolescence (Study 2), CBDV at both doses prevented the cognitive, social and acoustic alterations of adult Fmr1-KO mice and modified the expression of several inflammatory brain markers in both wild-type littermates and mutants. These findings warrant the therapeutic potential of CBDV for preventing neurobehavioral alterations associated with FXS, highlighting the relevance of its early administration. Full article
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28 pages, 793 KiB  
Article
Effects of Oral Cannabinoids on Systemic Inflammation and Viral Reservoir Markers in People with HIV on Antiretroviral Therapy: Results of the CTN PT028 Pilot Clinical Trial
by Ralph-Sydney Mboumba Bouassa, Eve Comeau, Yulia Alexandrova, Amélie Pagliuzza, Alexis Yero, Suzanne Samarani, Judy Needham, Joel Singer, Terry Lee, Florian Bobeuf, Claude Vertzagias, Giada Sebastiani, Shari Margolese, Enrico Mandarino, Marina B. Klein, Bertrand Lebouché, Jean-Pierre Routy, Nicolas Chomont, Cecilia T. Costiniuk and Mohammad-Ali Jenabian
Cells 2023, 12(14), 1811; https://doi.org/10.3390/cells12141811 - 08 Jul 2023
Cited by 4 | Viewed by 2066
Abstract
Chronic HIV infection is characterized by persistent inflammation despite antiretroviral therapy (ART). Cannabinoids may help reduce systemic inflammation in people with HIV (PWH). To assess the effects of oral cannabinoids during HIV, ten PWH on ART were randomized (n = 5/group) to [...] Read more.
Chronic HIV infection is characterized by persistent inflammation despite antiretroviral therapy (ART). Cannabinoids may help reduce systemic inflammation in people with HIV (PWH). To assess the effects of oral cannabinoids during HIV, ten PWH on ART were randomized (n = 5/group) to increasing doses of oral Δ9-tetrahydrocannabinol (THC): cannabidiol (CBD) combination (2.5:2.5–15:15 mg/day) capsules or CBD-only (200–800 mg/day) capsules for 12 weeks. Blood specimens were collected prospectively 7–21 days prior to treatment initiation and at weeks 0 to 14. Plasma cytokine levels were determined via Luminex and ELISA. Immune cell subsets were characterized by flow cytometry. HIV DNA/RNA were measured in circulating CD4 T-cells and sperm by ultra-sensitive qPCR. Results from both arms were combined for statistical analysis. Plasma levels of IFN-γ, IL-1β, sTNFRII, and REG-3α were significantly reduced at the end of treatment (p ˂ 0.05). A significant decrease in frequencies of PD1+ memory CD4 T-cells, CD73+ regulatory CD4 T-cells, and M-DC8+ intermediate monocytes was also observed (p ˂ 0.05), along with a transient decrease in CD28–CD57+ senescent CD4 and CD8 T-cells. Ki-67+ CD4 T-cells, CCR2+ non-classical monocytes, and myeloid dendritic cells increased over time (p ˂ 0.05). There were no significant changes in other inflammatory markers or HIV DNA/RNA levels. These findings can guide future large clinical trials investigating cannabinoid anti-inflammatory properties. Full article
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21 pages, 4423 KiB  
Article
Inhibition of Monoacylglycerol Lipase Decreases Angiogenic Features of Endothelial Cells via Release of Tissue Inhibitor of Metalloproteinase-1 from Lung Cancer Cells
by Felix Wittig, Lino Henkel, Jan Lukas Prüser, Jutta Merkord, Robert Ramer and Burkhard Hinz
Cells 2023, 12(13), 1757; https://doi.org/10.3390/cells12131757 - 30 Jun 2023
Cited by 3 | Viewed by 1319
Abstract
Despite the well-described anticarcinogenic effects of endocannabinoids, the influence of the endocannabinoid system on tumor angiogenesis is still debated. In the present study, conditioned medium (CM) from A549 and H358 lung cancer cells treated with ascending concentrations of the monoacylglycerol lipase (MAGL) inhibitor [...] Read more.
Despite the well-described anticarcinogenic effects of endocannabinoids, the influence of the endocannabinoid system on tumor angiogenesis is still debated. In the present study, conditioned medium (CM) from A549 and H358 lung cancer cells treated with ascending concentrations of the monoacylglycerol lipase (MAGL) inhibitor JZL184 and 2-arachidonoylglycerol (2-AG), a prominent MAGL substrate, caused a concentration-dependent reduction in human umbilical vein endothelial cell (HUVEC) migration and tube formation compared with CM from vehicle-treated cancer cells. Comparative experiments with MAGL inhibitors JW651 and MJN110 showed the same results. On the other hand, the angiogenic properties of HUVECs were not significantly altered by direct stimulation with JZL184 or 2-AG or by exposure to CM of JZL184- or 2-AG-treated non-cancerous bronchial epithelial cells (BEAS-2B). Inhibition of HUVEC migration and tube formation by CM of JZL184- and 2-AG-treated A549 cells was abolished in the presence of the CB1 antagonist AM-251. Increased release of tissue inhibitor of metalloproteinase-1 (TIMP-1) from JZL184- or 2-AG-stimulated A549 or H358 cells was shown to exert an antiangiogenic effect on HUVECs, as confirmed by siRNA experiments. In addition, JZL184 caused a dose-dependent regression of A549 tumor xenografts in athymic nude mice, which was associated with a decreased number of CD31-positive cells and upregulation of TIMP-1-positive cells in xenograft tissue. In conclusion, our data suggest that elevation of 2-AG by MAGL inhibition leads to increased release of TIMP-1 from lung cancer cells, which mediates an antiangiogenic effect on endothelial cells. Full article
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20 pages, 2475 KiB  
Review
Cannabinoid Signaling in Kidney Disease
by Liana Arceri, Thanh Khoa Nguyen, Shannon Gibson, Sophia Baker and Rebecca A. Wingert
Cells 2023, 12(10), 1419; https://doi.org/10.3390/cells12101419 - 18 May 2023
Cited by 1 | Viewed by 2131
Abstract
Endocannabinoid signaling plays crucial roles in human physiology in the function of multiple systems. The two cannabinoid receptors, CB1 and CB2, are cell membrane proteins that interact with both exogenous and endogenous bioactive lipid ligands, or endocannabinoids. Recent evidence has established that endocannabinoid [...] Read more.
Endocannabinoid signaling plays crucial roles in human physiology in the function of multiple systems. The two cannabinoid receptors, CB1 and CB2, are cell membrane proteins that interact with both exogenous and endogenous bioactive lipid ligands, or endocannabinoids. Recent evidence has established that endocannabinoid signaling operates within the human kidney, as well as suggests the important role it plays in multiple renal pathologies. CB1, specifically, has been identified as the more prominent ECS receptor within the kidney, allowing us to place emphasis on this receptor. The activity of CB1 has been repeatedly shown to contribute to both diabetic and non-diabetic chronic kidney disease (CKD). Interestingly, recent reports of acute kidney injury (AKI) have been attributed to synthetic cannabinoid use. Therefore, the exploration of the ECS, its receptors, and its ligands can help provide better insight into new methods of treatment for a range of renal diseases. This review explores the endocannabinoid system, with a focus on its impacts within the healthy and diseased kidney. Full article
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2022

Jump to: 2024, 2023

58 pages, 1912 KiB  
Review
Cannabinoid Compounds as a Pharmacotherapeutic Option for the Treatment of Non-Cancer Skin Diseases
by Robert Ramer and Burkhard Hinz
Cells 2022, 11(24), 4102; https://doi.org/10.3390/cells11244102 - 16 Dec 2022
Cited by 4 | Viewed by 3448
Abstract
The endocannabinoid system has been shown to be involved in various skin functions, such as melanogenesis and the maintenance of redox balance in skin cells exposed to UV radiation, as well as barrier functions, sebaceous gland activity, wound healing and the skin’s immune [...] Read more.
The endocannabinoid system has been shown to be involved in various skin functions, such as melanogenesis and the maintenance of redox balance in skin cells exposed to UV radiation, as well as barrier functions, sebaceous gland activity, wound healing and the skin’s immune response. In addition to the potential use of cannabinoids in the treatment and prevention of skin cancer, cannabinoid compounds and derivatives are of interest as potential systemic and topical applications for the treatment of various inflammatory, fibrotic and pruritic skin conditions. In this context, cannabinoid compounds have been successfully tested as a therapeutic option for the treatment of androgenetic alopecia, atopic and seborrhoeic dermatitis, dermatomyositis, asteatotic and atopic eczema, uraemic pruritis, scalp psoriasis, systemic sclerosis and venous leg ulcers. This review provides an insight into the current literature on cannabinoid compounds as potential medicines for the treatment of skin diseases. Full article
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21 pages, 2062 KiB  
Review
Neutral CB1 Receptor Antagonists as Pharmacotherapies for Substance Use Disorders: Rationale, Evidence, and Challenge
by Omar Soler-Cedeno and Zheng-Xiong Xi
Cells 2022, 11(20), 3262; https://doi.org/10.3390/cells11203262 - 17 Oct 2022
Cited by 8 | Viewed by 3819
Abstract
Cannabinoid receptor 1 (CB1R) has been one of the major targets in medication development for treating substance use disorders (SUDs). Early studies indicated that rimonabant, a selective CB1R antagonist with an inverse agonist profile, was highly promising as a therapeutic for SUDs. However, [...] Read more.
Cannabinoid receptor 1 (CB1R) has been one of the major targets in medication development for treating substance use disorders (SUDs). Early studies indicated that rimonabant, a selective CB1R antagonist with an inverse agonist profile, was highly promising as a therapeutic for SUDs. However, its adverse side effects, such as depression and suicidality, led to its withdrawal from clinical trials worldwide in 2008. Consequently, much research interest shifted to developing neutral CB1R antagonists based on the recognition that rimonabant’s side effects may be related to its inverse agonist profile. In this article, we first review rimonabant’s research background as a potential pharmacotherapy for SUDs. Then, we discuss the possible mechanisms underlying its therapeutic anti-addictive effects versus its adverse effects. Lastly, we discuss the rationale for developing neutral CB1R antagonists as potential treatments for SUDs, the supporting evidence in recent research, and the challenges of this strategy. We conclude that developing neutral CB1R antagonists without inverse agonist profile may represent attractive strategies for the treatment of SUDs. Full article
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10 pages, 1279 KiB  
Article
The Effects of Cannabidiol on Aqueous Humor Outflow and Trabecular Meshwork Cell Signaling
by Alyssa S. Aebersold and Zhao-Hui Song
Cells 2022, 11(19), 3006; https://doi.org/10.3390/cells11193006 - 27 Sep 2022
Cited by 3 | Viewed by 1742
Abstract
Intraocular pressure (IOP) is regulated primarily through aqueous humor production by ciliary body and drainage through uveoscleral and trabecular meshwork (TM) tissues. The goal of this study was to measure the effect of non-psychotropic cannabidiol (CBD) on aqueous humor outflow through TM and [...] Read more.
Intraocular pressure (IOP) is regulated primarily through aqueous humor production by ciliary body and drainage through uveoscleral and trabecular meshwork (TM) tissues. The goal of this study was to measure the effect of non-psychotropic cannabidiol (CBD) on aqueous humor outflow through TM and assess the effect of CBD on the TM cell signaling pathways that are important for regulating outflow. Perfused porcine eye anterior segment explants were used to investigate the effects of CBD on aqueous humor outflow. Cultured porcine TM cells were used to study the effects of CBD on TM cell contractility, myosin light chain (MLC) and myosin phosphatase targeting subunit 1 (MYPT1) phosphorylation, and RhoA activation. In the anterior segment perfusion experiments, aqueous humor outflow was increased significantly within 1 h after adding 1 µM CBD and the effect was sustained over the 5 h of measurement. Treatment of TM cells with 1 µM CBD significantly decreased TM cell-mediated collagen contraction, inhibited phosphorylation of MLC and MYPT1, and reduced RhoA activation. Our data demonstrate, for the first time, that as a potential therapeutic agent for lowering intraocular pressure, CBD can enhance aqueous humor outflow and modify TM cell signaling. Full article
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11 pages, 2128 KiB  
Article
WIN55212-2 Modulates Intracellular Calcium via CB1 Receptor-Dependent and Independent Mechanisms in Neuroblastoma Cells
by Victor M. Pulgar, Allyn C. Howlett and Khalil Eldeeb
Cells 2022, 11(19), 2947; https://doi.org/10.3390/cells11192947 - 21 Sep 2022
Cited by 2 | Viewed by 1594
Abstract
The CB1 cannabinoid receptor (CB1R) and extracellular calcium (eCa2+)-stimulated Calcium Sensing receptor (CaSR) can exert cellular signaling by modulating levels of intracellular calcium ([Ca2+]i). We investigated the mechanisms involved in the ([Ca2+] [...] Read more.
The CB1 cannabinoid receptor (CB1R) and extracellular calcium (eCa2+)-stimulated Calcium Sensing receptor (CaSR) can exert cellular signaling by modulating levels of intracellular calcium ([Ca2+]i). We investigated the mechanisms involved in the ([Ca2+]i) increase in N18TG2 neuroblastoma cells, which endogenously express both receptors. Changes in [Ca2+]i were measured in cells exposed to 0.25 or 2.5 mM eCa2+ by a ratiometric method (Fura-2 fluorescence) and expressed as the difference between baseline and peak responses (ΔF340/380). The increased ([Ca2+]i) in cells exposed to 2.5 mM eCa2+ was blocked by the CaSR antagonist, NPS2143, this inhibition was abrogated upon stimulation with WIN55212-2. WIN55212-2 increased [Ca2+]i at 0.25 and 2.5 mM eCa2+ by 700% and 350%, respectively, but this increase was not replicated by CP55940 or methyl-anandamide. The store-operated calcium entry (SOCE) blocker, MRS1845, attenuated the WIN55212-2-stimulated increase in [Ca2+]i at both levels of eCa2+. Simultaneous perfusion with the CB1 antagonist, SR141716 or NPS2143 decreased the response to WIN55212-2 at 0.25 mM but not 2.5 mM eCa2+. Co-perfusion with the non-CB1/CB2 antagonist O-1918 attenuated the WIN55212-2-stimulated [Ca2+]i increase at both eCa2+ levels. These results are consistent with WIN55212-2-mediated intracellular Ca2+ mobilization from store-operated calcium channel-filled sources that could occur via either the CB1R or an O-1918-sensitive non-CB1R in coordination with the CaSR. Intracellular pathway crosstalk or signaling protein complexes may explain the observed effects. Full article
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17 pages, 3536 KiB  
Article
Cross-Talk between CB1, AT1, AT2 and Mas Receptors Responsible for Blood Pressure Control in the Paraventricular Nucleus of Hypothalamus in Conscious Spontaneously Hypertensive Rats and Their Normotensive Controls
by Krzysztof Mińczuk, Eberhard Schlicker and Barbara Malinowska
Cells 2022, 11(9), 1542; https://doi.org/10.3390/cells11091542 - 04 May 2022
Cited by 4 | Viewed by 2098
Abstract
We have previously shown that in urethane-anaesthetized rats, intravenous injection of the angiotensin II (Ang II) AT1 receptor antagonist losartan reversed the pressor effect of the cannabinoid CB1 receptor agonist CP55940 given in the paraventricular nucleus of hypothalamus (PVN). The aim [...] Read more.
We have previously shown that in urethane-anaesthetized rats, intravenous injection of the angiotensin II (Ang II) AT1 receptor antagonist losartan reversed the pressor effect of the cannabinoid CB1 receptor agonist CP55940 given in the paraventricular nucleus of hypothalamus (PVN). The aim of our study was to determine the potential interactions in the PVN between CB1 receptors and AT1 and AT2 receptors for Ang II and Mas receptors for Ang 1–7 in blood pressure regulation in conscious spontaneously hypertensive (SHR) and normotensive Wistar Kyoto (WKY) rats. The pressor effects of Ang II, Ang 1–7 and CP55940 microinjected into the PVN were stronger in SHRs than in WKYs. Increases in blood pressure in response to Ang II were strongly inhibited by antagonists of AT1 (losartan), AT2 (PD123319) and CB1 (AM251) receptors, to Ang 1–7 by a Mas antagonist (A-779) and AM251 and to CP55940 by losartan, PD123319 and A-779. Higher (AT1 and CB1) and lower (AT2 and Mas) receptor expression in the PVN of SHR compared to WKY may partially explain the above differences. In conclusion, blood pressure control in the PVN depends on the mutual interaction of CB1, AT1, AT2 and Mas receptors in conscious spontaneously hypertensive rats and their normotensive controls. Full article
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20 pages, 2737 KiB  
Article
Cannabinoids Alleviate the LPS-Induced Cytokine Storm via Attenuating NLRP3 Inflammasome Signaling and TYK2-Mediated STAT3 Signaling Pathways In Vitro
by Santosh V. Suryavanshi, Mariia Zaiachuk, Nazar Pryimak, Igor Kovalchuk and Olga Kovalchuk
Cells 2022, 11(9), 1391; https://doi.org/10.3390/cells11091391 - 20 Apr 2022
Cited by 27 | Viewed by 4375
Abstract
Cannabinoids, mainly cannabidiol (CBD) and Δ9-tetrahydrocannabinol (THC), are the most studied group of compounds obtained from Cannabis sativa because of their several pharmaceutical properties. Current evidence suggests a crucial role of cannabinoids as potent anti-inflammatory agents for the treatment of chronic [...] Read more.
Cannabinoids, mainly cannabidiol (CBD) and Δ9-tetrahydrocannabinol (THC), are the most studied group of compounds obtained from Cannabis sativa because of their several pharmaceutical properties. Current evidence suggests a crucial role of cannabinoids as potent anti-inflammatory agents for the treatment of chronic inflammatory diseases; however, the mechanisms remain largely unclear. Cytokine storm, a dysregulated severe inflammatory response by our immune system, is involved in the pathogenesis of numerous chronic inflammatory disorders, including coronavirus disease 2019 (COVID-19), which results in the accumulation of pro-inflammatory cytokines. Therefore, we hypothesized that CBD and THC reduce the levels of pro-inflammatory cytokines by inhibiting key inflammatory signaling pathways. The nucleotide-binding and oligomerization domain (NOD)-like receptor family pyrin domain-containing 3 (NLRP3) inflammasome signaling has been implicated in a variety of chronic inflammatory diseases, which results in the release of pyroptotic cytokines, interleukin-1β (IL-1β) and IL-18. Likewise, the activation of the signal transducer and activator of transcription-3 (STAT3) causes increased expression of pro-inflammatory cytokines. We studied the effects of CBD and THC on lipopolysaccharide (LPS)-induced inflammatory response in human THP-1 macrophages and primary human bronchial epithelial cells (HBECs). Our results revealed that CBD and, for the first time, THC significantly inhibited NLRP3 inflammasome activation following LPS + ATP stimulation, leading to a reduction in the levels of IL-1β in THP-1 macrophages and HBECs. CBD attenuated the phosphorylation of nuclear factor-κB (NF-κB), and both cannabinoids inhibited the generation of oxidative stress post-LPS. Our multiplex ELISA data revealed that CBD and THC significantly diminished the levels of IL-6, IL-8, and tumor necrosis factor-α (TNF-α) after LPS treatment in THP-1 macrophages and HBECs. In addition, the phosphorylation of STAT3 was significantly downregulated by CBD and THC in THP-1 macrophages and HBECs, which was in turn attributed to the reduced phosphorylation of tyrosine kinase-2 (TYK2) by CBD and THC after LPS stimulation in these cells. Overall, CBD and THC were found to be effective in alleviating the LPS-induced cytokine storm in human macrophages and primary HBECs, at least via modulation of NLRP3 inflammasome and STAT3 signaling pathways. The encouraging results from this study warrant further investigation of these cannabinoids in vivo. Full article
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22 pages, 943 KiB  
Review
Microglial Endocannabinoid Signalling in AD
by Lucia Scipioni, Francesca Ciaramellano, Veronica Carnicelli, Alessandro Leuti, Anna Rita Lizzi, Noemi De Dominicis, Sergio Oddi and Mauro Maccarrone
Cells 2022, 11(7), 1237; https://doi.org/10.3390/cells11071237 - 06 Apr 2022
Cited by 9 | Viewed by 2625
Abstract
Chronic inflammation in Alzheimer’s disease (AD) has been recently identified as a major contributor to disease pathogenesis. Once activated, microglial cells, which are brain-resident immune cells, exert several key actions, including phagocytosis, chemotaxis, and the release of pro- or anti-inflammatory mediators, which could [...] Read more.
Chronic inflammation in Alzheimer’s disease (AD) has been recently identified as a major contributor to disease pathogenesis. Once activated, microglial cells, which are brain-resident immune cells, exert several key actions, including phagocytosis, chemotaxis, and the release of pro- or anti-inflammatory mediators, which could have opposite effects on brain homeostasis, depending on the stage of disease and the particular phenotype of microglial cells. The endocannabinoids (eCBs) are pleiotropic bioactive lipids increasingly recognized for their essential roles in regulating microglial activity both under normal and AD-driven pathological conditions. Here, we review the current literature regarding the involvement of this signalling system in modulating microglial phenotypes and activity in the context of homeostasis and AD-related neurodegeneration. Full article
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38 pages, 1720 KiB  
Review
Why Do Marijuana and Synthetic Cannabimimetics Induce Acute Myocardial Infarction in Healthy Young People?
by Jolanta Weresa, Anna Pędzińska-Betiuk, Krzysztof Mińczuk, Barbara Malinowska and Eberhard Schlicker
Cells 2022, 11(7), 1142; https://doi.org/10.3390/cells11071142 - 28 Mar 2022
Cited by 12 | Viewed by 5364
Abstract
The use of cannabis preparations has steadily increased. Although cannabis was traditionally assumed to only have mild vegetative side effects, it has become evident in recent years that severe cardiovascular complications can occur. Cannabis use has recently even been added to the risk [...] Read more.
The use of cannabis preparations has steadily increased. Although cannabis was traditionally assumed to only have mild vegetative side effects, it has become evident in recent years that severe cardiovascular complications can occur. Cannabis use has recently even been added to the risk factors for myocardial infarction. This review is dedicated to pathogenetic factors contributing to cannabis-related myocardial infarction. Tachycardia is highly important in this respect, and we provide evidence that activation of CB1 receptors in brain regions important for cardiovascular regulation and of presynaptic CB1 receptors on sympathetic and/or parasympathetic nerve fibers are involved. The prototypical factors for myocardial infarction, i.e., thrombus formation and coronary constriction, have also been considered, but there is little evidence that they play a decisive role. On the other hand, an increase in the formation of carboxyhemoglobin, impaired mitochondrial respiration, cardiotoxic reactions and tachyarrhythmias associated with the increased sympathetic tone are factors possibly intensifying myocardial infarction. A particularly important factor is that cannabis use is frequently accompanied by tobacco smoking. In conclusion, additional research is warranted to decipher the mechanisms involved, since cannabis use is being legalized increasingly and Δ9-tetrahydrocannabinol and its synthetic analogue nabilone are indicated for the treatment of various disease states. Full article
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21 pages, 37660 KiB  
Article
Artificial Intelligent Deep Learning Molecular Generative Modeling of Scaffold-Focused and Cannabinoid CB2 Target-Specific Small-Molecule Sublibraries
by Yuemin Bian and Xiang-Qun Xie
Cells 2022, 11(5), 915; https://doi.org/10.3390/cells11050915 - 07 Mar 2022
Cited by 6 | Viewed by 4209
Abstract
Design and generation of high-quality target- and scaffold-specific small molecules is an important strategy for the discovery of unique and potent bioactive drug molecules. To achieve this goal, authors have developed the deep-learning molecule generation model (DeepMGM) and applied it for the de [...] Read more.
Design and generation of high-quality target- and scaffold-specific small molecules is an important strategy for the discovery of unique and potent bioactive drug molecules. To achieve this goal, authors have developed the deep-learning molecule generation model (DeepMGM) and applied it for the de novo molecular generation of scaffold-focused small-molecule libraries. In this study, a recurrent neural network (RNN) using long short-term memory (LSTM) units was trained with drug-like molecules to result in a general model (g-DeepMGM). Sampling practices on indole and purine scaffolds illustrate the feasibility of creating scaffold-focused chemical libraries based on machine intelligence. Subsequently, a target-specific model (t-DeepMGM) for cannabinoid receptor 2 (CB2) was constructed following the transfer learning process of known CB2 ligands. Sampling outcomes can present similar properties to the reported active molecules. Finally, a discriminator was trained and attached to the DeepMGM to result in an in silico molecular design-test circle. Medicinal chemistry synthesis and biological validation was performed to further investigate the generation outcome, showing that XIE9137 was identified as a potential allosteric modulator of CB2. This study demonstrates how recent progress in deep learning intelligence can benefit drug discovery, especially in de novo molecular design and chemical library generation. Full article
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