Endogenous Cannabinoid-Like Arachidonoyl Serine Protects Against LPS-Induced Endothelial Apoptosis.

Abstract The endocannabinoid system is involved in several physiological processes, and has been reported to have neuroprotective and vasoprotective effects. N-Arachidonoyl Serine (ARA-S), a recently identified endocannabinoid, possesses vasodilatory properties and shows protective effects on the endothelium. ARA-S does not bind to the CB1, CB2, or vanilloid TRPV1 receptors, and most likely binds to an endothelial-specific cannabinoid receptor. This receptor has not yet been identified. We previously found that ARA-S can enhance endothelial wound healing in vitro. Now, we demonstrate that ARA-S can protect endothelial cells from lipopolysaccharide (LPS)-mediated apoptosis, a pathological process which commonly occurs during infection and inflammation. Human primary dermal microvascular endothelial cells (HMVEC) expressing both CB1 and CB2 receptors were used in our functional and biochemical assays. Upon pretreatment of HMVEC with ARA-S (1 μM), LPS-induced apoptosis was significantly diminished by 25–30% compared to treatment with the vehicle control, as shown by in situ TUNEL staining and Annexin V/Propidium Iodide (PI) co-staining assays in live cells. This ARA-S-mediated protection was dose-dependent and could be partially blocked by specific CB1 and CB2 antagonists (AM251 and AM630), either individually or in combination. Other receptors besides CB1 and CB2 appeared to be involved in this process, since O-1918, a blocker of the putative third cannabinoid receptor, also inhibited the activity of ARA-S by 80%. To decipher how ARA-S changes the fate of these cells, we compared LPS-induced signaling cascades in HMVEC in the presence or absence of ARA-S. ARA-S activated both Akt and eNOS in the LPS-treated HMVEC, two important molecules for endothelial survival. In contrast, ARA-S inhibited the activities of Caspase 9 and Cytochrome C, which were induced by LPS and cause cell apoptosis. Our findings support a role for novel endocannabinoids like ARA-S that may interact with putative cannabinoid receptors in protecting the cardiovascular system from toxic stimuli like LPS.

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Therapeutic Attributes of Endocannabinoid System against Neuro-Inflammatory Autoimmune Disorders

Molecules ◽

10.3390/molecules26113389 ◽

2021 ◽

Vol 26 (11) ◽

pp. 3389

Author(s):

Ishtiaq Ahmed ◽

Saif Ur Rehman ◽

Shiva Shahmohamadnejad ◽

Muhammad Anjum Zia ◽

Muhammad Ahmad ◽

...

Keyword(s):

Cannabinoid Receptors ◽

Cannabinoid Receptor ◽

Therapeutic Potential ◽

Endocannabinoid System ◽

Cell Types ◽

Autoimmune Disorders ◽

Specific Receptors ◽

Different Cell Types

In humans, various sites like cannabinoid receptors (CBR) having a binding affinity with cannabinoids are distributed on the surface of different cell types, where endocannabinoids (ECs) and derivatives of fatty acid can bind. The binding of these substance(s) triggers the activation of specific receptors required for various physiological functions, including pain sensation, memory, and appetite. The ECs and CBR perform multiple functions via the cannabinoid receptor 1 (CB1); cannabinoid receptor 2 (CB2), having a key effect in restraining neurotransmitters and the arrangement of cytokines. The role of cannabinoids in the immune system is illustrated because of their immunosuppressive characteristics. These characteristics include inhibition of leucocyte proliferation, T cells apoptosis, and induction of macrophages along with reduced pro-inflammatory cytokines secretion. The review seeks to discuss the functional relationship between the endocannabinoid system (ECS) and anti-tumor characteristics of cannabinoids in various cancers. The therapeutic potential of cannabinoids for cancer—both in vivo and in vitro clinical trials—has also been highlighted and reported to be effective in mice models in arthritis for the inflammation reduction, neuropathic pain, positive effect in multiple sclerosis and type-1 diabetes mellitus, and found beneficial for treating in various cancers. In human models, such studies are limited; thereby, further research is indispensable in this field to get a conclusive outcome. Therefore, in autoimmune disorders, therapeutic cannabinoids can serve as promising immunosuppressive and anti-fibrotic agents.

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Pregnancy success in mice requires appropriate cannabinoid receptor signaling for primary decidua formation

eLife ◽

10.7554/elife.61762 ◽

2020 ◽

Vol 9 ◽

Author(s):

Yingju Li ◽

Amanda Dewar ◽

Yeon Sun Kim ◽

Sudhansu K Dey ◽

Xiaofei Sun

Keyword(s):

Endothelial Cells ◽

Stromal Cells ◽

Cannabinoid Receptors ◽

Cannabinoid Receptor ◽

Angiogenic Factors ◽

Permeable Barrier ◽

Size Dependent ◽

Decidual Cells ◽

Avascular Zone

With implantation, mouse stromal cells begin to transform into epithelial-like cells surrounding the implantation chamber forming an avascular zone called the primary decidual zone (PDZ). In the mouse, the PDZ forms a transient, size-dependent permeable barrier to protect the embryo from maternal circulating harmful agents. The process of decidualization is critical for pregnancy maintenance in mice and humans. Mice deficient in cannabinoid receptors, CB1 and CB2, show compromised PDZ with dysregulated angiogenic factors, resulting in the retention of blood vessels and macrophages. This phenotype is replicated in Cnr1-/- but not in Cnr2-/-mice. In vitro decidualization models suggest that Cnr1 levels substantially increase in mouse and human decidualizing stromal cells, and that neutralization of CB1 signaling suppresses decidualization and misregulates angiogenic factors. Taken together, we propose that implantation quality depends on appropriate angiogenic events driven by the integration of CB2 in endothelial cells and CB1 in decidual cells.

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Discovery of Orexant and Anorexant Agents with Indazole Scaffold Endowed with Peripheral Antiedema Activity

Biomolecules ◽

10.3390/biom9090492 ◽

2019 ◽

Vol 9 (9) ◽

pp. 492 ◽

Cited By ~ 5

Author(s):

Dimmito ◽

Stefanucci ◽

Pieretti ◽

Minosi ◽

Dvorácskó ◽

...

Keyword(s):

Feeding Behavior ◽

Cannabinoid Receptors ◽

Cannabinoid Receptor ◽

Methyl Esters ◽

Endocannabinoid System ◽

Tail Flick ◽

Binding Assays ◽

Tail Flick Test

The endocannabinoid system represents an integrated neuronal network involved in the control of several organisms’ functions, such as feeding behavior. A series of hybrids of 5-(4-chlorophenyl)-1-(2,4-dichloro-phenyl)-4-methyl-N-(piperidin-1-yl)-1H-pyrazole-3-carboxamide (mimonabant), a well-known inverse agonist of the type-1 cannabinoid receptor (CB1), once used as an antiobesity drug, and the N-(2S)-substitutes of 1-[(4-fluorophenyl)methyl]indazole-3-carboxamide with 1-amino-3-methyl-1-oxobutane (AB-Fubinaca), 1-amino-3,3-dimethyl-1-oxobutane (ADB-Fubinaca), and 3-methylbutanoate (AMB-Fubinaca), endowed with potent agonistic activity towards cannabinoid receptors CB1 and CB2 were in solution as C-terminal amides, acids, methyl esters and N-methyl amides. These compounds have been studied by binding assays to cannabinoid receptors and by functional receptor assays, using rat brain membranes in vitro. The most active among them as an agonist, (S)-1-(2,4-dichlorobenzyl)-N-(3,3-dimethyl-1-(methylamino)-1-oxobutan-2-yl)-1H-indazole-3-carboxamide (LONI11), and an antagonist, (S)-2-(1-(2,4-dichlorobenzyl)-1H-indazole-3-carboxamido)-3-methylbutanoic acid (LONI4), were tested in vivo in mic, to evaluate their ability to stimulate or suppress feeding behavior after intraperitoneal (i.p.) administration. For a LONI11 formalin test and a tail flick test after an administration by the subcutaneous (s.c.) and intracerebroventricular (i.c.v.) routes, respectively, were also carried out in vivo in mice to investigate the antinociceptive property at the central and peripheral levesl. We observed a significant orexant effect for LONI11 and an intense anorexant effect for (S)-methyl 2-(1-(2,4-dichlorobenzyl)-1H-indazole-3-carboxamido)-3,3-dimethylbutanoate (LONI2) and LONI4. In zymosan-induced edema and hyperalgesia, LONI11 reduced the percent of paw volume increase and paw latency after s.c. administration, also suggesting a possible peripheral anti-inflammatory activity.

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P4140Myeloid but not endothelial expression of the CB2 receptor promotes atherogenesis in the context of elevated levels of the endocannabinoid 2-arachidonoylglycerol

European Heart Journal ◽

10.1093/eurheartj/ehz745.0712 ◽

2019 ◽

Vol 40 (Supplement_1) ◽

Author(s):

J Jehle ◽

E Avraamidou ◽

M Danisch ◽

S Bagheri ◽

B Schoene ◽

...

Keyword(s):

Endothelial Cells ◽

Mouse Models ◽

Plasma Levels ◽

Cannabinoid Receptors ◽

Endocannabinoid System ◽

Receptor Expression ◽

Mrna Levels ◽

Cb2 Receptor ◽

Deficient Mice

Abstract Background The endocannabinoid 2-arachidonoylglycerol (2-AG) is an inflammatory mediator and ligand to the cannabinoid receptors CB1 and CB2, which are expressed on myeloid and endothelial cells. 2-AG has recently been described to promote atherogenesis in ApoE-deficient mice. While the CB2 receptor has previously been considered to solely exert anti-inflammatory and atheroprotective effects, newer data have raised the notion, that CB2 might exert atherogenic effects in the context of elevated 2-AG plasma levels. In the present study, we investigated the atherogenic mechanisms of 2-AG and the role of the CB2 receptor on myeloid and endothelial cells in atherogenesis using cell-specific knockout mouse models. Methods Two mouse models with atherogenic background and distinct cell-specific knockouts of the CB2 receptor on myeloid (ApoE−/−LysMcreCB2fl/fl) or endothelial cells (ApoE−/−Tie2creCB2fl/fl) were created. Mice were treated with JZL184, which inhibits 2-AG-degrading enzyme monoacylglycerol lipase, and thereby elevates 2-AG plasma levels, or with vehicle (DMSO), while being fed a high-fat diet for four weeks. Plaque volume and plaque composition were analyzed. In vitro, macrophages were treated with 2-AG and mRNA levels of adhesion molecules, scavenger receptors and chemokines, the production of reactive oxygen species (ROS) and the release of myeloperoxidase (MPO) were determined using qPCR, fluorometric assays and ELISA respectively. Results Elevated levels of 2-AG promote atherogenesis in ApoE-deficient mice (JZL184 vs. DMSO: 39.6±2.1% vs. 32.6±2.4%; n=14; p<0.05). The atherogenic effect of 2-AG is abrogated in mice lacking myeloid CB2 receptor expression (35.0±2.0% vs. 34.0±2.5%; n=14–16; p>0.05) but not in mice lacking endothelial CB2 receptor expression (37.1±3.1% vs. 20.9±2.6%; n=10–12; p<0.01). In vitro, 2-AG significantly increases transcription of adhesion molecule ICAM-1 (2.09±0.42 –fold; n=5–6; p<0.05), chemokine receptor CCR-1 (2.04±0.46 -fold; n=10–11; p<0.05) and scavenger receptor CD36 (8.02±1.89-fold; n=3; p<0.05) in 2-AG-treated macrophages. These effects are mitigated by pharmacological inhibition of CB2. Furthermore, 2-AG significantly increases myeloperoxidase (MPO) release in monocytes in a CB receptor-dependent fashion (451±23 pg/ml vs. 151±8.3 pg/ml; n=3–4; p<0.01) and promotes ROS production (2698±24 pdu vs. 1981±27 pdu; n=8; p<0.01). Conclusion Elevated 2-AG levels show an atherogenic effect in vivo which is dependent on the presence of the CB2 receptor on myeloid cells. Our in vitro data reveal 2-AG to promote pro-inflammatory signaling in macrophages and elucidate a previously unrecognized link between the endocannabinoid system and MPO in monocytes. In summary, cell-specific effects of the endocannabinoid system will have to be taken into account to facilitate its exploitation as an anti-atherosclerotic drug target. Acknowledgement/Funding This work was supported by the Bonfor program of the University of Bonn [grant number O-109.0057 to JJ].

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Endocannabinoid system acts as a regulator of immune homeostasis in the gut

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1612177114 ◽

2017 ◽

Vol 114 (19) ◽

pp. 5005-5010 ◽

Cited By ~ 47

Author(s):

Nandini Acharya ◽

Sasi Penukonda ◽

Tatiana Shcheglova ◽

Adam T. Hagymasi ◽

Sreyashi Basu ◽

...

Keyword(s):

Cannabinoid Receptors ◽

Cannabinoid Receptor ◽

Endocannabinoid System ◽

Nod Mice ◽

Immune Homeostasis ◽

Dependent Manner ◽

Mice Model ◽

Nonobese Diabetic

Endogenous cannabinoids (endocannabinoids) are small molecules biosynthesized from membrane glycerophospholipid. Anandamide (AEA) is an endogenous intestinal cannabinoid that controls appetite and energy balance by engagement of the enteric nervous system through cannabinoid receptors. Here, we uncover a role for AEA and its receptor, cannabinoid receptor 2 (CB2), in the regulation of immune tolerance in the gut and the pancreas. This work demonstrates a major immunological role for an endocannabinoid. The pungent molecule capsaicin (CP) has a similar effect as AEA; however, CP acts by engagement of the vanilloid receptor TRPV1, causing local production of AEA, which acts through CB2. We show that the engagement of the cannabinoid/vanilloid receptors augments the number and immune suppressive function of the regulatory CX3CR1hi macrophages (Mϕ), which express the highest levels of such receptors among the gut immune cells. Additionally, TRPV1−/− or CB2−/− mice have fewer CX3CR1hi Mϕ in the gut. Treatment of mice with CP also leads to differentiation of a regulatory subset of CD4+ cells, the Tr1 cells, in an IL-27–dependent manner in vitro and in vivo. In a functional demonstration, tolerance elicited by engagement of TRPV1 can be transferred to naïve nonobese diabetic (NOD) mice [model of type 1 diabetes (T1D)] by transfer of CD4+ T cells. Further, oral administration of AEA to NOD mice provides protection from T1D. Our study unveils a role for the endocannabinoid system in maintaining immune homeostasis in the gut/pancreas and reveals a conversation between the nervous and immune systems using distinct receptors.

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Epidermal Endocannabinoid System (EES) and its Cosmetic Application

Cosmetics ◽

10.3390/cosmetics6020033 ◽

2019 ◽

Vol 6 (2) ◽

pp. 33

Author(s):

Sekyoo Jeong ◽

Min Kim ◽

Sin Lee ◽

Byeong Park

Keyword(s):

Cannabinoid Receptors ◽

Cannabinoid Receptor ◽

Inflammatory Responses ◽

Endocannabinoid System ◽

Major Constituent ◽

Health Improvement ◽

Hemp Seed ◽

Therapeutic Benefits

Recently, cannabis, or its major constituent cannabidiol (CBD), has emerged as an attractive cosmetic ingredient. Initiated as a basic investigation of the physiological roles of cannabinoid receptors and their endogenous ligands, endocannabinoids’ diverse potential benefits have been proposed for using cannabinoid receptor modulating compounds in skin health. Improvement in skin barrier functions, alleviating inflammatory responses, and the relief of itching sensations are some commonly expected therapeutic benefits, which have been supported by many in vitro, in vivo, and clinical studies. While hemp seed oils or hemp extracts might be used for the cosmetic formulation, the potential for contamination with a psychoactive cannabinoid, such as 9-THC, should be carefully checked. Instead of using hemp-derived ingredients, the use of cannabinomimetics, synthetic ligands on cannabinoid receptors, or entourage compounds (which modulate intracellular synthesis and the degradation of endocannabinoids), have been tried. In this review, a brief introduction of the epidermal endocannabinoid system (EES) and its physiological roles will be followed by a review of the cosmetic and dermatologic application of cannabinomimetics and entourage compounds. The practical application of newly developed endocannabinomimetics will be discussed as well.

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Alpha-Asarone Protects Endothelial Cells from Injury by Angiotensin II

Evidence-based Complementary and Alternative Medicine ◽

10.1155/2014/682041 ◽

2014 ◽

Vol 2014 ◽

pp. 1-7 ◽

Cited By ~ 3

Author(s):

Hai-Xia Shi ◽

Jiajun Yang ◽

Tao Yang ◽

Yong-Liang Xue ◽

Jun Liu ◽

...

Keyword(s):

Nitric Oxide ◽

Endothelial Cells ◽

Angiotensin Ii ◽

Cell Injury ◽

Fluorescent Dyes ◽

Umbilical Vein ◽

Protective Effects ◽

Ang Ii ◽

Versus Model

α-Asarone is the major therapeutical constituent ofAcorus tatarinowiiSchott. In this study, the potential protective effects ofα-asarone against endothelial cell injury induced by angiotensin II were investigatedin vitro. The EA.hy926 cell line derived from human umbilical vein endothelial cells was pretreated withα-asarone (10, 50, 100 µmol/L) for 1 h, followed by coincubation with Ang II (0.1 µmol/L) for 24 h. Intracellular nitric oxide (NO) and reactive oxygen species (ROS) were detected by fluorescent dyes, and phosphorylation of endothelial nitric oxide synthase (eNOS) atSer1177was determined by Western blotting.α-Asarone dose-dependently mitigated the Ang II-induced intracellular NO reduction (P<0.01versus model) and ROS production (P<0.01versus model). Furthermore, eNOS phosphorylation (Ser1177) by acetylcholine was significantly inhibited by Ang II, while pretreatment for 1 h withα-asarone partially prevented this effect (P<0.05versus model). Additionally, cell viability determined by the MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] assay (105~114.5% versus control,P>0.05) was not affected after 24 h of incubation withα-asarone at 1–100 µmol/L. Therefore,α-asarone protects against Ang II-mediated damage of endothelial cells and may be developed to prevent injury to cardiovascular tissues.

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Vaspin Alleviates Osteoarthritis by Inhibiting NLRP3-mediated Inflammation

10.21203/rs.3.rs-285169/v1 ◽

2021 ◽

Author(s):

Xianjie Zhu ◽

Shiyou Dai ◽

Baohua Xia ◽

Jianbao Gong ◽

Bingzheng Ma

Keyword(s):

Nlrp3 Inflammasome ◽

Wistar Rat ◽

Cartilage Degradation ◽

Pathological Process ◽

Inflammasome Activation ◽

Protective Effects ◽

Collagen Formation ◽

Nlrp3 Inflammasome Activation

Abstract Background:Osteoarthritis (OA) is a chronic degenerative joint bone disease characterized by cartilage degradation. Visceral adipose tissue-derived serine protease inhibitor (vaspin) is associated with the inflammatory and metabolic responses to OA. However, the underlying mechanisms of the pathological process of OA are not clear. The aim of the present study was to examine the protective effects of vaspin both in vitro and in vivo.Methods:Monosodium iodoacetate (MIA)-induced Wistar rat model of OA was used to assess the in vivo effects of vaspin administered for 12 weeks. The characteristics of OA were evaluated by haematoxylin and eosin (H&E) and safranin O/fast green staining. The anti-inflammatory effect of vaspin was assessed using immunohistochemical, qRT-PCR, and western blotting analysis. Parallel experiments to detect the molecular mechanism through which vaspin prevents OA were performed using LPS-treated chondrocytes.Results:Our results showed that the degeneration of cartilage and upregulated expression of matrix metalloproteinase (MMP)-1 and MMP-13 were ameliorated by vaspin. Additionally, vaspin suppressed the activation of TXNIP/NLRP3 and secretion of tumor necrosis factor ɑ and interleukin-1β in vivo. It was further confirmed that vaspin could also suppress LPS-induced NLRP3 inflammasome activation and reduce collagen formation in chondrocytes. Moreover, vaspin inhibited NLRP3 inflammasome activation by suppressing the ROS/TXNIP pathway.Conclusions: Vaspin inhibited OA by repressing TXNIP/NLRP3 activation in in vitro and in vivo models of OA, thus providing a novel therapeutic strategy for OA.

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GPR18, GPR55 and GPR119 (version 2019.4) in the IUPHAR/BPS Guide to Pharmacology Database

IUPHAR/BPS Guide to Pharmacology CITE ◽

10.2218/gtopdb/f114/2019.4 ◽

2019 ◽

Vol 2019 (4) ◽

Author(s):

Stephen P.H. Alexander ◽

Andrew J. Irving

Keyword(s):

Cannabinoid Receptors ◽

Cannabinoid Receptor ◽

Structural Similarity ◽

Synthetic Cannabinoid ◽

Receptor Ligands ◽

Orphan Status ◽

Endogenous Cannabinoid

GPR18, GPR55 and GPR119 (provisional nomenclature), although showing little structural similarity to CB1 and CB2 cannabinoid receptors, respond to endogenous agents analogous to the endogenous cannabinoid ligands, as well as some natural/synthetic cannabinoid receptor ligands [98]. Although there are multiple reports to indicate that GPR18, GPR55 and GPR119 can be activated in vitro by N-arachidonoylglycine, lysophosphatidylinositol and N-oleoylethanolamide, respectively, there is a lack of evidence for activation by these lipid messengers in vivo. As such, therefore, these receptors retain their orphan status.

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Distribution of the Cannabinoid Receptor Type 1 in the Brain of the Genetically Audiogenic Seizure-Prone Hamster GASH/Sal

Frontiers in Behavioral Neuroscience ◽

10.3389/fnbeh.2021.613798 ◽

2021 ◽

Vol 15 ◽

Author(s):

Alejando Fuerte-Hortigón ◽

Jaime Gonçalves ◽

Laura Zeballos ◽

Rubén Masa ◽

Ricardo Gómez-Nieto ◽

...

Keyword(s):

Cannabinoid Receptors ◽

Cannabinoid Receptor ◽

Endocannabinoid System ◽

Brain Regions ◽

Audiogenic Seizure ◽

Type I ◽

Sound Stimulation ◽

Differential Distribution ◽

Central Type ◽

Anatomical Basis

The endocannabinoid system modulates epileptic seizures by regulating neuronal excitability. It has become clear that agonist activation of central type I cannabinoid receptors (CB1R) reduces epileptogenesis in pre-clinical animal models of epilepsy. The audiogenic seizure-prone hamster GASH/Sal is a reliable experimental model of generalized tonic-clonic seizures in response to intense sound stimulation. However, no studies hitherto had investigated CB1R in the GASH/Sal. Although the distribution of CB1R has been extensively studied in mammalian brains, their distribution in the Syrian golden hamster brain also remains unknown. The objective of this research is to determine by immunohistochemistry the differential distribution of CB1R in the brains of GASH/Sal animals under seizure-free conditions, by comparing the results with wild-type Syrian hamsters as controls. CB1R in the GASH/Sal showed a wide distribution in many nuclei of the central nervous system. These patterns of CB1R-immunolabeling are practically identical between the GASH/Sal model and control animals, varying in the intensity of immunostaining in certain regions, being slightly weaker in the GASH/Sal than in the control, mainly in brain regions associated with epileptic networks. The RT-qPCR analysis confirms these results. In summary, our study provides an anatomical basis for further investigating CB1R in acute and kindling audiogenic seizure protocols in the GASH/Sal model as well as exploring CB1R activation via exogenously administered cannabinoid compounds.

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