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Sample records for cannabinoid receptor agonist

  1. Emerging strategies for exploiting cannabinoid receptor agonists as medicines.

    Science.gov (United States)

    Pertwee, Roger G

    2009-02-01

    Medicines that activate cannabinoid CB(1) and CB(2) receptor are already in the clinic. These are Cesamet (nabilone), Marinol (dronabinol; Delta(9)-tetrahydrocannabinol) and Sativex (Delta(9)-tetrahydrocannabinol with cannabidiol). The first two of these medicines can be prescribed to reduce chemotherapy-induced nausea and vomiting. Marinol can also be prescribed to stimulate appetite, while Sativex is prescribed for the symptomatic relief of neuropathic pain in adults with multiple sclerosis and as an adjunctive analgesic treatment for adult patients with advanced cancer. One challenge now is to identify additional therapeutic targets for cannabinoid receptor agonists, and a number of potential clinical applications for such agonists are mentioned in this review. A second challenge is to develop strategies that will improve the efficacy and/or the benefit-to-risk ratio of a cannabinoid receptor agonist. This review focuses on five strategies that have the potential to meet either or both of these objectives. These are strategies that involve: (i) targeting cannabinoid receptors located outside the blood-brain barrier; (ii) targeting cannabinoid receptors expressed by a particular tissue; (iii) targeting up-regulated cannabinoid receptors; (iv) targeting cannabinoid CB(2) receptors; or (v) 'multi-targeting'. Preclinical data that justify additional research directed at evaluating the clinical importance of each of these strategies are also discussed. PMID:19226257

  2. Targeting the endocannabinoid system with cannabinoid receptor agonists: pharmacological strategies and therapeutic possibilities.

    Science.gov (United States)

    Pertwee, Roger G

    2012-12-01

    Human tissues express cannabinoid CB(1) and CB(2) receptors that can be activated by endogenously released 'endocannabinoids' or exogenously administered compounds in a manner that reduces the symptoms or opposes the underlying causes of several disorders in need of effective therapy. Three medicines that activate cannabinoid CB(1)/CB(2) receptors are now in the clinic: Cesamet (nabilone), Marinol (dronabinol; Δ(9)-tetrahydrocannabinol (Δ(9)-THC)) and Sativex (Δ(9)-THC with cannabidiol). These can be prescribed for the amelioration of chemotherapy-induced nausea and vomiting (Cesamet and Marinol), stimulation of appetite (Marinol) and symptomatic relief of cancer pain and/or management of neuropathic pain and spasticity in adults with multiple sclerosis (Sativex). This review mentions several possible additional therapeutic targets for cannabinoid receptor agonists. These include other kinds of pain, epilepsy, anxiety, depression, Parkinson's and Huntington's diseases, amyotrophic lateral sclerosis, stroke, cancer, drug dependence, glaucoma, autoimmune uveitis, osteoporosis, sepsis, and hepatic, renal, intestinal and cardiovascular disorders. It also describes potential strategies for improving the efficacy and/or benefit-to-risk ratio of these agonists in the clinic. These are strategies that involve (i) targeting cannabinoid receptors located outside the blood-brain barrier, (ii) targeting cannabinoid receptors expressed by a particular tissue, (iii) targeting upregulated cannabinoid receptors, (iv) selectively targeting cannabinoid CB(2) receptors, and/or (v) adjunctive 'multi-targeting'. PMID:23108552

  3. Human metabolites of synthetic cannabinoids JWH-018 and JWH-073 bind with high affinity and act as potent agonists at cannabinoid type-2 receptors

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    Rajasekaran, Maheswari; Brents, Lisa K.; Franks, Lirit N. [Department of Pharmacology and Toxicology, University of Arkansas for Medical Sciences, Little Rock, AR 72205 (United States); Moran, Jeffery H. [Department of Pharmacology and Toxicology, University of Arkansas for Medical Sciences, Little Rock, AR 72205 (United States); Arkansas Department of Public Health, Public Health Laboratory, Little Rock, AR 72205 (United States); Prather, Paul L., E-mail: pratherpaull@uams.edu [Department of Pharmacology and Toxicology, University of Arkansas for Medical Sciences, Little Rock, AR 72205 (United States)

    2013-06-01

    K2 or Spice is an emerging drug of abuse that contains synthetic cannabinoids, including JWH-018 and JWH-073. Recent reports indicate that monohydroxylated metabolites of JWH-018 and JWH-073 retain high affinity and activity at cannabinoid type-1 receptors (CB{sub 1}Rs), potentially contributing to the enhanced toxicity of K2 compared to marijuana. Since the parent compounds also bind to cannabinoid type-2 receptors (CB{sub 2}Rs), this study investigated the affinity and intrinsic activity of JWH-018, JWH-073 and several monohydroxylated metabolites at human CB{sub 2}Rs (hCB{sub 2}Rs). The affinity of cannabinoids for hCB{sub 2}Rs was determined by competition binding studies employing CHO-hCB{sub 2} membranes. Intrinsic activity of compounds was assessed by G-protein activation and adenylyl cyclase (AC)-inhibition in CHO-hCB{sub 2} cells. JWH-073, JWH-018 and several of their human metabolites exhibit nanomolar affinity and act as potent agonists at hCB{sub 2}Rs. Furthermore, a major omega hydroxyl metabolite of JWH-073 (JWH-073-M5) binds to CB{sub 2}Rs with 10-fold less affinity than the parent molecule, but unexpectedly, is equipotent in regulating AC-activity when compared to the parent molecule. Finally, when compared to CP-55,940 and Δ{sup 9}-tetrahydrocannabinol (Δ{sup 9}-THC), JWH-018, JWH-018-M5 and JWH-073-M5 require significantly less CB{sub 2}R occupancy to produce similar levels of AC-inhibition, indicating that these compounds may more efficiently couple CB{sub 2}Rs to AC than the well characterized cannabinoid agonists examined. These results indicate that JWH-018, JWH-073 and several major human metabolites of these compounds exhibit high affinity and demonstrate distinctive signaling properties at CB{sub 2}Rs. Therefore, future studies examining pharmacological and toxicological properties of synthetic cannabinoids present in K2 products should consider potential actions of these drugs at both CB{sub 1} and CB{sub 2}Rs. - Highlights: • JWH-018

  4. Human metabolites of synthetic cannabinoids JWH-018 and JWH-073 bind with high affinity and act as potent agonists at cannabinoid type-2 receptors

    International Nuclear Information System (INIS)

    K2 or Spice is an emerging drug of abuse that contains synthetic cannabinoids, including JWH-018 and JWH-073. Recent reports indicate that monohydroxylated metabolites of JWH-018 and JWH-073 retain high affinity and activity at cannabinoid type-1 receptors (CB1Rs), potentially contributing to the enhanced toxicity of K2 compared to marijuana. Since the parent compounds also bind to cannabinoid type-2 receptors (CB2Rs), this study investigated the affinity and intrinsic activity of JWH-018, JWH-073 and several monohydroxylated metabolites at human CB2Rs (hCB2Rs). The affinity of cannabinoids for hCB2Rs was determined by competition binding studies employing CHO-hCB2 membranes. Intrinsic activity of compounds was assessed by G-protein activation and adenylyl cyclase (AC)-inhibition in CHO-hCB2 cells. JWH-073, JWH-018 and several of their human metabolites exhibit nanomolar affinity and act as potent agonists at hCB2Rs. Furthermore, a major omega hydroxyl metabolite of JWH-073 (JWH-073-M5) binds to CB2Rs with 10-fold less affinity than the parent molecule, but unexpectedly, is equipotent in regulating AC-activity when compared to the parent molecule. Finally, when compared to CP-55,940 and Δ9-tetrahydrocannabinol (Δ9-THC), JWH-018, JWH-018-M5 and JWH-073-M5 require significantly less CB2R occupancy to produce similar levels of AC-inhibition, indicating that these compounds may more efficiently couple CB2Rs to AC than the well characterized cannabinoid agonists examined. These results indicate that JWH-018, JWH-073 and several major human metabolites of these compounds exhibit high affinity and demonstrate distinctive signaling properties at CB2Rs. Therefore, future studies examining pharmacological and toxicological properties of synthetic cannabinoids present in K2 products should consider potential actions of these drugs at both CB1 and CB2Rs. - Highlights: • JWH-018 and JWH-073 are synthetic cannabinoids present in abused K2 products. • JWH-018, JWH-073 and

  5. Mead ethanolamide, a novel eicosanoid, is an agonist for the central (CB1) and peripheral (CB2) cannabinoid receptors.

    Science.gov (United States)

    Priller, J; Briley, E M; Mansouri, J; Devane, W A; Mackie, K; Felder, C C

    1995-08-01

    The recently discovered endogenous agonist for the cannabinoid receptor, anandamide (arachidonylethanolamide), can be formed enzymatically by the condensation of arachidonic acid with ethanolamine. 5Z,8Z,11Z-Eicosatrienoic acid (mead acid) has been found to substitute for arachidonic acid in the sn-2 position of phospholipids and accumulate during periods of dietary fatty acid deprivation in rats. In the present study, the chemically synthesized ethanolamide of mead acid was evaluated as a potential agonist at the two known subtypes of cannabinoid receptor: CB1 (central) and CB2 (peripheral). This compound was equipotent to anandamide in competing with [3H]CP55,940 binding to plasma membranes prepared from L cells expressing the human CB1 receptor and from ATt-20 cells expressing the human CB2 receptor. Mead ethanolamide was also equipotent to anandamide in inhibiting forskolin-stimulated cAMP accumulation in cells expressing the CB1 receptor. It inhibited N-type calcium currents with a lower potency than anandamide. Mead and arachidonic acid were equally efficacious as substrates for the enzymatic synthesis of their respective ethanolamides in rat and adult human hippocampal P2 membranes. Palmitic acid was not an effective substrate for the enzymatic synthesis of palmitoyl ethanolamide. Mead ethanolamide exhibits several characteristics of a novel agonist to CB1 and CB2 receptors and may represent another candidate endogenous ligand for the CB1 receptor. Due to the anticonvulsant properties of GABA and the positional similarity of L-serine to ethanolamine in membrane phospholipids, these compounds were synthetically coupled to arachidonic acid, and their resulting arachidonamides were tested as potential cannabinoid agonists. The arachidonamides of GABA and L-serine were inactive in both binding and functional assays at the CB1 receptor. PMID:7651362

  6. The discovery of taranabant, a selective cannabinoid-1 receptor inverse agonist for the treatment of obesity.

    Science.gov (United States)

    Hagmann, William K

    2008-07-01

    The cannabinoid-1 receptor (CB1R) has emerged as one of the most important targets for the treatment of obesity. Pioneering studies with rimonabant helped to validate animal models of food intake reduction and weight loss and made the connection to weight loss in the clinic. A novel, acyclic amide was identified from a high throughput screen (HTS) of the Merck sample collection and found to be a potent and selective CB1R inhibitor. Further optimization led to more potent compounds that were orally active in reducing food intake and weight loss in diet-induced obese (DIO) rats. However, many of these analogues exhibited a high potential for bioactivation and the formation of reactive intermediates and covalent protein binding. Identification of the products of oxidative metabolism guided medicinal chemistry efforts to minimize the formation of these unwanted products. These efforts resulted in the identification of the CB1R inverse agonist, taranabant, which is currently in Phase-III clinical studies for the treatment of obesity. This mini-review will describe some of the medicinal chemistry strategies that were followed from the original high throughput screen hit to the discovery of taranabant. PMID:18574849

  7. Blockade of Nicotine and Cannabinoid Reinforcement and Relapse by a Cannabinoid CB1-Receptor Neutral Antagonist AM4113 and Inverse Agonist Rimonabant in Squirrel Monkeys.

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    Schindler, Charles W; Redhi, Godfrey H; Vemuri, Kiran; Makriyannis, Alexandros; Le Foll, Bernard; Bergman, Jack; Goldberg, Steven R; Justinova, Zuzana

    2016-08-01

    Nicotine, the main psychoactive component of tobacco, and (-)-Δ(9)-tetrahydrocannabinol (THC), the main psychoactive ingredient in cannabis, play major roles in tobacco and marijuana dependence as reinforcers of drug-seeking and drug-taking behavior. Drugs that act as inverse agonists of cannabinoid CB1 receptors in the brain can attenuate the rewarding and abuse-related effects of nicotine and THC, but their clinical use is hindered by potentially serious side effects. The recently developed CB1-receptor neutral antagonists may provide an alternative therapeutic approach to nicotine and cannabinoid dependence. Here we compare attenuation of nicotine and THC reinforcement and reinstatement in squirrel monkeys by the CB1-receptor inverse agonist rimonabant and by the recently developed CB1-receptor neutral antagonist AM4113. Both rimonabant and AM4113 reduced two effects of nicotine and THC that play major roles in tobacco and marijuana dependence: (1) maintenance of high rates of drug-taking behavior, and (2) priming- or cue-induced reinstatement of drug-seeking behavior in abstinent subjects (models of relapse). In contrast, neither rimonabant nor AM4113 modified cocaine-reinforced or food-reinforced operant behavior under similar experimental conditions. However, both rimonabant and AM4113 reduced cue-induced reinstatement in monkeys trained to self-administer cocaine, suggesting the involvement of a common cannabinoid-mediated mechanism in the cue-induced reinstatement for different drugs of abuse. These findings point to CB1-receptor neutral antagonists as a new class of medications for treatment of both tobacco dependence and cannabis dependence. PMID:26888056

  8. Peripherally Selective Cannabinoid 1 Receptor (CB1R) Agonists for the Treatment of Neuropathic Pain.

    Science.gov (United States)

    Seltzman, Herbert H; Shiner, Craig; Hirt, Erin E; Gilliam, Anne F; Thomas, Brian F; Maitra, Rangan; Snyder, Rod; Black, Sherry L; Patel, Purvi R; Mulpuri, Yatendra; Spigelman, Igor

    2016-08-25

    Alleviation of neuropathic pain by cannabinoids is limited by their central nervous system (CNS) side effects. Indole and indene compounds were engineered for high hCB1R affinity, peripheral selectivity, metabolic stability, and in vivo efficacy. An epithelial cell line assay identified candidates with <1% blood-brain barrier penetration for testing in a rat neuropathy induced by unilateral sciatic nerve entrapment (SNE). The SNE-induced mechanical allodynia was reversibly suppressed, partially or completely, after intraperitoneal or oral administration of several indenes. At doses that relieve neuropathy symptoms, the indenes completely lacked, while the brain-permeant CB1R agonist HU-210 (1) exhibited strong CNS side effects, in catalepsy, hypothermia, and motor incoordination assays. Pharmacokinetic findings of ∼0.001 cerebrospinal fluid:plasma ratio further supported limited CNS penetration. Pretreatment with selective CB1R or CB2R blockers suggested mainly CB1R contribution to an indene's antiallodynic effects. Therefore, this class of CB1R agonists holds promise as a viable treatment for neuropathic pain. PMID:27482723

  9. The Neuroprotective Effect of Cannabinoid Receptor Agonist (WIN55,212-2 in Paraoxon Induced Neurotoxicity in PC12 Cells and N-methyl-D-aspartate Receptor Interaction

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    Hedayat Sahraei

    2010-01-01

    Full Text Available Objective: Considering that cannabinoids protect neurons against neurodegeneration, inthis study, the neuroprotective effect of WIN55,212-2 in paraoxon induced neurotoxicity inPC12 cells and the role of the N-methyl-D-aspartate (NMDA receptor were evaluated.Materials and Methods: In this study PC12 cells were maintained in Dulbecco's modifiedeagle’s medium (DMEM+F12 culture medium supplemented with 10% fetal bovineserum. The cells were treated with paraoxon (200 μM in the presence or absence ofWIN55,212-2 (0.1 μM, NMDA receptor agonist NMDA (100 μM, cannabinoid receptorantagonist AM251 and NMDA receptor antagonist MK801 (1 μM at 15 minutes intervals.After 48 hours of exposure, cellular viability and protein expression of the CB1 receptorwere evaluated in PC12 cells.Results: Following the exposure of PC12 cells to paraoxon (200 μM, a reduction in cellsurvival and protein level of the CB1 receptor was observed (p<0.01. Treatment of thecells with WIN55,212-2 (0.1 μM and NMDA (100 μM prior to paraoxon exposure significantlyelevated cell survival and protein level of the CB1 receptor (p<0.01. Also, AM251(1μM did not inhibit the cell survival and protein level of the CB1 receptor increase inducedby WIN55,212-2 (p<0.001. However, MK801 (1 μM did inhibit cell survival andprotein expression of the CB1 receptor increase induced by NMDA (p<0.001.Conclusion: The results indicate that WIN55,212-2 and NMDA protect PC12 cellsagainst paraoxon induced toxicity. In addition, the neuroprotective effect of WIN55,212-2and NMDA was cannabinoid receptor-independent and NMDA receptor dependent, respectively.

  10. Lipid Bilayer Molecular Dynamics Study of Lipid-Derived Agonists of the Putative Cannabinoid Receptor, GPR55

    OpenAIRE

    Kotsikorou, Evangelia; Lynch, Diane L.; Abood, Mary E.; Reggio, Patricia H.

    2010-01-01

    Both L-α-lysophosphatidylinositol (LPI) and 2-arachidonoyl-sn-glycero-3-phosphoinositol (2-AGPI) have been reported to activate the putative cannabinoid receptor, GPR55. Recent microsecond time-scale molecular dynamics (MD) simulations and isothiocyanate covalent labeling studies have suggested that a transmembrane helix 6/7 (TMH6/7) lipid pathway for ligand entry may be necessary for interaction with cannabinoid receptors. Because LPI and 2-AGPI are lipid-derived ligands, conformations that ...

  11. Cannabinoid receptor agonist protects cultured dopaminergic neurons from the death by the proteasomal dysfunction

    OpenAIRE

    Jeon, Posung; Yang, Sungjun; Jeong, Hojoong; Kim, Hyun

    2011-01-01

    Cannabinoids have been proposed to possess neuroprotective properties; though their mechanism of action remains contentious, they are posited to prevent neurodegenerative disorders, including Parkinson's disease, the pathogenesis of which has not been established. Recent studies have demonstrated that induction of proteasomal dysfunction in animal models results in a phenotype similar to Parkinson's disease. Here, we investigated the neuroprotective function of a synthetic cannabinoid-recepto...

  12. Adolescent exposure to nicotine and/or the cannabinoid agonist CP 55,940 induces gender-dependent long-lasting memory impairments and changes in brain nicotinic and CB(1) cannabinoid receptors.

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    Mateos, B; Borcel, E; Loriga, R; Luesu, W; Bini, V; Llorente, R; Castelli, M P; Viveros, M-P

    2011-12-01

    We have analysed the long-term effects of adolescent (postnatal day 28-43) exposure of male and female rats to nicotine (NIC, 1.4 mg/kg/day) and/or the cannabinoid agonist CP 55,940 (CP, 0.4 mg/kg/day) on the following parameters measured in the adulthood: (1) the memory ability evaluated in the object location task (OL) and in the novel object test (NOT); (2) the anxiety-like behaviour in the elevated plus maze; and (3) nicotinic and CB(1) cannabinoid receptors in cingulated cortex and hippocampus. In the OL, all pharmacological treatments induced significant decreases in the DI of females, whereas no significant effects were found among males. In the NOT, NIC-treated females showed a significantly reduced DI, whereas the effect of the cannabinoid agonist (a decrease in the DI) was only significant in males. The anxiety-related behaviour was not changed by any drug. Both, nicotine and cannabinoid treatments induced a long-lasting increase in CB(1) receptor activity (CP-stimulated GTPγS binding) in male rats, and the nicotine treatment also induced a decrease in nicotinic receptor density in the prefrontal cortex of females. The results show gender-dependent harmful effects of both drugs and long-lasting changes in CB(1) and nicotinic receptors.

  13. Cannabinoid receptor subtype 2 (CB2R) agonist, GW405833 reduces agonist-induced Ca2+ oscillations in mouse pancreatic acinar cells

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    Huang, Zebing; Wang, Haiyan; Wang, Jingke; Zhao, Mengqin; Sun, Nana; Sun, Fangfang; Shen, Jianxin; Zhang, Haiying; Xia, Kunkun; Chen, Dejie; Gao, Ming; Hammer, Ronald P.; Liu, Qingrong; Xi, Zhengxiong; Fan, Xuegong; Wu, Jie

    2016-01-01

    Emerging evidence demonstrates that the blockade of intracellular Ca2+ signals may protect pancreatic acinar cells against Ca2+ overload, intracellular protease activation, and necrosis. The activation of cannabinoid receptor subtype 2 (CB2R) prevents acinar cell pathogenesis in animal models of acute pancreatitis. However, whether CB2Rs modulate intracellular Ca2+ signals in pancreatic acinar cells is largely unknown. We evaluated the roles of CB2R agonist, GW405833 (GW) in agonist-induced Ca2+ oscillations in pancreatic acinar cells using multiple experimental approaches with acute dissociated pancreatic acinar cells prepared from wild type, CB1R-knockout (KO), and CB2R-KO mice. Immunohistochemical labeling revealed that CB2R protein was expressed in mouse pancreatic acinar cells. Electrophysiological experiments showed that activation of CB2Rs by GW reduced acetylcholine (ACh)-, but not cholecystokinin (CCK)-induced Ca2+ oscillations in a concentration-dependent manner; this inhibition was prevented by a selective CB2R antagonist, AM630, or was absent in CB2R-KO but not CB1R-KO mice. In addition, GW eliminated L-arginine-induced enhancement of Ca2+ oscillations, pancreatic amylase, and pulmonary myeloperoxidase. Collectively, we provide novel evidence that activation of CB2Rs eliminates ACh-induced Ca2+ oscillations and L-arginine-induced enhancement of Ca2+ signaling in mouse pancreatic acinar cells, which suggests a potential cellular mechanism of CB2R-mediated protection in acute pancreatitis. PMID:27432473

  14. Cannabinoid receptor subtype 2 (CB2R) agonist, GW405833 reduces agonist-induced Ca(2+) oscillations in mouse pancreatic acinar cells.

    Science.gov (United States)

    Huang, Zebing; Wang, Haiyan; Wang, Jingke; Zhao, Mengqin; Sun, Nana; Sun, Fangfang; Shen, Jianxin; Zhang, Haiying; Xia, Kunkun; Chen, Dejie; Gao, Ming; Hammer, Ronald P; Liu, Qingrong; Xi, Zhengxiong; Fan, Xuegong; Wu, Jie

    2016-01-01

    Emerging evidence demonstrates that the blockade of intracellular Ca(2+) signals may protect pancreatic acinar cells against Ca(2+) overload, intracellular protease activation, and necrosis. The activation of cannabinoid receptor subtype 2 (CB2R) prevents acinar cell pathogenesis in animal models of acute pancreatitis. However, whether CB2Rs modulate intracellular Ca(2+) signals in pancreatic acinar cells is largely unknown. We evaluated the roles of CB2R agonist, GW405833 (GW) in agonist-induced Ca(2+) oscillations in pancreatic acinar cells using multiple experimental approaches with acute dissociated pancreatic acinar cells prepared from wild type, CB1R-knockout (KO), and CB2R-KO mice. Immunohistochemical labeling revealed that CB2R protein was expressed in mouse pancreatic acinar cells. Electrophysiological experiments showed that activation of CB2Rs by GW reduced acetylcholine (ACh)-, but not cholecystokinin (CCK)-induced Ca(2+) oscillations in a concentration-dependent manner; this inhibition was prevented by a selective CB2R antagonist, AM630, or was absent in CB2R-KO but not CB1R-KO mice. In addition, GW eliminated L-arginine-induced enhancement of Ca(2+) oscillations, pancreatic amylase, and pulmonary myeloperoxidase. Collectively, we provide novel evidence that activation of CB2Rs eliminates ACh-induced Ca(2+) oscillations and L-arginine-induced enhancement of Ca(2+) signaling in mouse pancreatic acinar cells, which suggests a potential cellular mechanism of CB2R-mediated protection in acute pancreatitis. PMID:27432473

  15. Novel selective cannabinoid CB1 receptor antagonist MJ08 with potent in vivo bioactivity and inverse agonistic effects

    Institute of Scientific and Technical Information of China (English)

    Wei CHEN; Cheng XU; Hong-ying LIU; Long LONG; Wei ZHANG; Zhi-bing ZHENG; Yun-de XIE; Li-li WANG; Song LI

    2011-01-01

    To characterize the biological profiles of M J08,a novel selective CB1 receptor antagonist.Methods:Radioligand binding assays were performed using rat brain and spleen membrane preparations.CB1 and CB2 receptor redistribution and intracellular Ca2+ ([Ca2+]1) assays were performed with IN CELL Analyzer.Inverse agonism was studied using intracellular cAMP assays,and in guinea-pig ileum and mouse vas deferens smooth muscle preparations.In vivo pharmacologic profile was assessed in diet-induced obesity (DIO) mice.Results:In radioligand binding assay,M J08 selectively antagonized CB1 receptor (IC50=99.9 nmol/L).In EGFP-CB1_U20S cells,its IC50 value against CB1 receptor activation was 30.23 nmol/L (SR141716A:32.16 nmol/L).WIN 55,212-2 (1 μmol/L) increased [Ca2+]1 in the primary cultured hippocampal neuronal cells and decreased cAMP accumulation in CHO-hCB1 cells.M J08 (10 nmol/L-1O μmol/L)blocked both the WIN 55,212-2-induced effects.Furthermore,M J08 reversed the inhibition of electrically evoked twitches of mouse vas deferens by WIN 55,212-2 (pA2=10.29±1.05).M J08 and SR141716A both showed an inverse agonism activity by markedly promoting the contraction force and frequency of guinea pig ileum muscle.M J08 significantly increased the cAMP level in CHO-hCB1 cells with an EC50 value of 78.6 nmol/L,which was lower than the EC50 value for SR141716A (159.2 nmol/L).Besides the more potent pharmacological effects of cannabinoid CB1 receptor antagonism in DIO mice,such as reducing food intake,decreasing body weight,and ameliorating dyslipidemia,M J08 (10 mg/kg) unexpectedly raised the fasted blood glucose in vivo.Conclusion:M J08 is a novel,potent and selective CB1 receptor antagonist/inverse agonist with potent bioactive responses in vitro and in vivo that may be useful for disclosure the versatile nature of CB1 receptors.

  16. ACEA (a highly selective cannabinoid CB1 receptor agonist) stimulates hippocampal neurogenesis in mice treated with antiepileptic drugs.

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    Andres-Mach, Marta; Haratym-Maj, Agnieszka; Zagaja, Miroslaw; Rola, Radoslaw; Maj, Maciej; Chrościńska-Krawczyk, Magdalena; Luszczki, Jarogniew J

    2015-10-22

    Hippocampal neurogenesis plays a very important role in learning and memory functions. In a search for best neurological drugs that protect neuronal cells and stimulate neurogenesis with no side effects, cannabinoids proved to be a strong group of substances having many beneficial properties. The aim of this study was to evaluate the impact of ACEA (arachidonyl-2'-chloroethylamide--a highly selective cannabinoid CB1 receptor agonist) combined with a classical antiepileptic drug sodium valproate (VPA) on neural precursor cells' proliferation and differentiation in the mouse brain. All experiments were performed on adolescent CB57/BL male mice injected i.p. with VPA (10mg/kg), ACEA (10mg/kg) and PMSF (30 mg/kg) (phenylmethylsulfonyl fluoride--a substance protecting ACEA against degradation by the fatty-acid amidohydrolase) for 10 days. Next an acute response of proliferating neural precursor cells to ACEA and VPA administration was evaluated with Ki-67 staining (Time point 1). Next, in order to determine whether acute changes translated into long-term alterations in neurogenesis, proliferating cells were labeled with 5-bromo-2deoxyuridine (BrdU) followed by confocal microscopy used to determine the percentage of BrdU-labeled cells that showed mature cell phenotypes (Time point 2). Results indicate that ACEA with PMSF significantly increase the total number of Ki-67-positive cells when compared to the control group. Moreover, ACEA in combination with VPA increased the number of Ki-67-positive cells, whereas VPA administered alone had no impact on proliferating cells' population. Accordingly, neurogenesis study results indicate that the combination of ACEA+PMSF administered alone and in combination with VPA considerably increases the total number of BrdU-positive cells in comparison to the control group while ACEA+PMSF alone and in combination with VPA increased total numbers of BrdU-positive cells, newly born neurons and astrocytes as compared to VPA group but not to

  17. Contribution of hypothermia and CB1 receptor activation to protective effects of TAK-937, a cannabinoid receptor agonist, in rat transient MCAO model.

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    Noriko Suzuki

    Full Text Available BACKGROUND: Cannabinoid (CB receptor agonists are expected to alleviate ischemic brain damage by modulating neurotransmission and neuroinflammatory responses via CB(1 and CB(2 receptors, respectively. In a previous study, TAK-937, a novel potent and selective CB(1 and CB(2 receptor agonist, was shown to exert significant cerebroprotective effects accompanied by hypothermia after transient middle cerebral artery occlusion (MCAO in rats. Sustained hypothermia itself induces significant neuroprotective effects. In the present studies, we examined the relative contribution of hypothermia and CB(1 receptor activation to the cerebroprotective effects of TAK-937. METHODOLOGY/PRINCIPAL FINDINGS: Using a multichannel brain temperature controlling system we developed, the brain temperature of freely moving rats was telemetrically monitored and maintained between 37 and 38°C during intravenous infusion of TAK-937 (100 µg/kg/h or vehicle for 24 h after 2 h MCAO. AM251, a selective CB(1 receptor antagonist, was administered intraperitoneally at 30 mg/kg 30 min before starting intravenous infusion of TAK-937 (100 µg/kg/h for 24 h. Rats were sacrificed and their brains were isolated 26 h after MCAO in both experiments. When the hypothermic effect of TAK-937 was completely reversed by a brain temperature controlling system, the infarct-reducing effect of TAK-937 was attenuated in part, but remained significant. On the other hand, concomitant AM251 treatment with TAK-937 completely abolished the hypothermic and infarct-reducing effects of TAK-937. CONCLUSIONS/SIGNIFICANCE: We conclude that the cerebroprotective effects of TAK-937 were at least in part mediated by induction of hypothermia, and mainly mediated by CB(1 receptor activation.

  18. Interaction between orexin A and cannabinoid system in the lateral hypothalamus of rats and effects of subchronic intraperitoneal administration of cannabinoid receptor inverse agonist on food intake and the nutritive utilization of protein.

    Science.gov (United States)

    Merroun, I; El Mlili, N; Martinez, R; Porres, J M; Llopis, J; Ahabrach, H; Aranda, P; Sanchez Gonzalez, C; Errami, M; Lopez-Jurado, M

    2015-04-01

    Crosstalk may occur between cannabinoids and other systems controlling appetite, since cannabinoid receptors are present in hypothalamic circuits involved in feeding regulation, and likely to interact with orexin. In this study, an immunohistochemical approach was used to examine the effect of the intracerebroventricular administration of cannabinoid receptor inverse agonist AM 251 on orexin neuropeptide in the hypothalamic system. AM-activated neurons were identified using c-Fos as a marker of neuronal activity. The results obtained show that AM 251 decreases orexin A immunoreactivity, and that it increases c-Fos-immunoreactive neurons within the hypothalamus when compared with the vehicle-injected control group. We also studied the effects of subchronic intraperitoneal administration of AM 251 on food intake, body weight, and protein utilization. The administration of AM 251 at 1, 2, or 5 mg/kg led to a significant reduction in food intake, along with a significant decrease in the digestive utilization of protein in the groups injected with 1 and 2 mg/kg. There was a dose-related slowdown in weight gain, especially at the doses of 2 and 5 mg/kg, during the initial days of the trial. The absence of this effect in the pair-fed group reveals that any impairment to digestibility was the result of administering AM 251. These data support our conclusion that hypothalamic orexigenic neuropeptides are involved in the reduction of appetite and mediated by the cannabinoid receptor inverse agonist. Furthermore, the subchronic administration of AM 251, in addition to its effect on food intake, has significant effects on the digestive utilization of protein. PMID:25903949

  19. Cannabinoid receptor-2 (CB2) agonist ameliorates colitis in IL-10{sup −/−} mice by attenuating the activation of T cells and promoting their apoptosis

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    Singh, Udai P.; Singh, Narendra P. [Pathology, Microbiology and Immunology, School of Medicine, University of South Carolina, Columbia, SC 29208 (United States); Singh, Balwan [National Primate Research Center, Emory University, Atlanta GA 30329 (United States); Price, Robert L. [Department of Cell and Developmental Biology, University of South Carolina, Columbia, SC 29208 (United States); Nagarkatti, Mitzi [Pathology, Microbiology and Immunology, School of Medicine, University of South Carolina, Columbia, SC 29208 (United States); Nagarkatti, Prakash S., E-mail: Prakash.Nagarkatti@uscmed.sc.edu [Pathology, Microbiology and Immunology, School of Medicine, University of South Carolina, Columbia, SC 29208 (United States)

    2012-01-15

    Inflammatory bowel disease (IBD) is a chronic intestinal inflammation caused by hyperactivated effector immune cells that produce pro-inflammatory cytokines. Recent studies have shown that the cannabinoid system may play a critical role in mediating protection against intestinal inflammation. However, the effect of cannabinoid receptor induction after chronic colitis progression has not been investigated. Here, we investigate the effect of cannabinoid receptor-2 (CB2) agonist, JWH-133, after chronic colitis in IL-10{sup −/−} mice. JWH-133 effectively attenuated the overall clinical score, and reversed colitis-associated pathogenesis and decrease in body weight in IL-10{sup −/−} mice. After JWH-133 treatment, the percentage of CD4{sup +} T cells, neutrophils, mast cells, natural killer (NK1.1) cells, and activated T cells declined in the intestinal lamina propria (LP) and mesenteric lymph nodes (MLN) of mice with chronic colitis. JWH-133 was also effective in ameliorating dextran sodium sulfate (DSS)-induced colitis. In this model, JWH-133 reduced the number and percentage of macrophages and IFN-γ expressing cells that were induced during colitis progression. Treatment with aminoalkylindole 6-iodo-pravadoline (AM630), a CB2 receptor antagonist, reversed the colitis protection provided by JWH-133 treatment. Also, activated T cells were found to undergo apoptosis following JWH-133 treatment both in-vivo and in-vitro. These findings suggest that JWH-133 mediates its effect through CB2 receptors, and ameliorates chronic colitis by inducing apoptosis in activated T cells, reducing the numbers of activated T cells, and suppressing induction of mast cells, NK cells, and neutrophils at sites of inflammation in the LP. These results support the idea that the CB2 receptor agonists may serve as a therapeutic modality against IBD. -- Highlights: ► JWH-133, a cannnabinoid receptor-2 agonist ameliorates experimental colitis. ► JWH-133 suppressed inflammation and

  20. Molecular-Interaction and Signaling Profiles of AM3677, a Novel Covalent Agonist Selective for the Cannabinoid 1 Receptor

    OpenAIRE

    David R Janero; Yaddanapudi, Suma; Zvonok, Nikolai; Subramanian, Kumar V.; Shukla, Vidyanand G.; Stahl, Edward; Zhou, Lei; Hurst, Dow; Wager-Miller, James; Bohn, Laura M.; Reggio, Patricia H.; Mackie, Ken; Makriyannis, Alexandros

    2015-01-01

    The cannabinoid 1 receptor (CB1R) is one of the most abundant G protein-coupled receptors (GPCRs) in the central nervous system. CB1R involvement in multiple physiological processes, especially neurotransmitter release and synaptic function, has made this GPCR a prime drug discovery target, and pharmacological CB1R activation has been demonstrated to be a tenable therapeutic modality. Accordingly, the design and profiling of novel, drug-like CB1R modulators to inform the receptor’s ligand-int...

  1. The CB1 cannabinoid receptor agonist reduces L-DOPA-induced motor fluctuation and ERK1/2 phosphorylation in 6-OHDA-lesioned rats.

    Science.gov (United States)

    Song, Lu; Yang, Xinxin; Ma, Yaping; Wu, Na; Liu, Zhenguo

    2014-01-01

    The dopamine precursor L-3,4-dihydroxyphenylalanine (L-DOPA) has been used as an effective drug for treating dopamine depletion-induced Parkinson's disease (PD). However, long-term administration of L-DOPA produces motor complications. L-DOPA has also been found to modify the two key signaling cascades, protein kinase A/dopamine- and cAMP-regulated phosphoprotein of 32 kDa (DARPP-32) and extracellular signal-regulated kinases 1 and 2 (ERK1/2), in striatal neurons, which are thought to play a pivotal role in forming motor complications. In the present study, we tested the possible effect of a CB1 cannabinoid receptor agonist on L-DOPA-stimulated abnormal behavioral and signaling responses in vivo. Intermittent L-DOPA administration for 3 weeks induced motor fluctuation in a rat model of PD induced by intrastriatal infusion of dopamine-depleting neurotoxin 6-hydroxydopamine (6-OHDA). A single injection of a CB1 cannabinoid receptor agonist WIN-55,212-2 had no effect on L-DOPA-induced motor fluctuation. However, chronic injections of WIN-55,212-2 significantly attenuated abnormal behavioral responses to L-DOPA in 6-OHDA-lesioned rats. Similarly, chronic injections of WIN-55,212-2 influence the L-DOPA-induced alteration of DARPP-32 and ERK1/2 phosphorylation status in striatal neurons. These data provide evidence for the active involvement of CB1 cannabinoid receptors in the regulation of L-DOPA action during PD therapy.

  2. Unconditioned and conditioned anxiogenic effects of the cannabinoid receptor agonist CP 55,940 in the social interaction test.

    Science.gov (United States)

    Genn, Rachel F; Tucci, Sonia; Marco, Eva M; Viveros, M Paz; File, Sandra E

    2004-03-01

    In spite of the addictive properties of cannabinoids, under certain circumstances, they can evoke strong anxiogenic and aversive responses in humans and in animal tests of anxiety. Effects of different doses of CP 55,940 (10, 20, and 40 microg/kg) were tested in the low-light, familiar (LF) apparatus test condition of the social interaction test. The 40-microg/kg dose of CP 55,940 significantly decreased the time spent in social interaction, indicating an anxiogenic effect. This dose also had an independent effect of reducing locomotor activity. In rats tested undrugged 24 h after testing with 40 microg/kg, there was a significant anxiogenic effect, indicating conditioned anxiety. The group of rats injected with 40 microg/kg immediately after the social interaction test showed an unexpected significant anxiolytic effect when tested undrugged 24 h later. In an additional experiment, rats were tested in the high-light, familiar (HF) apparatus test condition after 10 or 40 microg/kg, and only those that were tested after 40 microg/kg showed an anxiogenic effect on the test day and a conditioned anxiogenic effect when tested undrugged 24 h later. Once again, those injected with 40 microg/kg after the social interaction test displayed an anxiolytic effect when tested undrugged 24 h later. We provide the first evidence for unconditioned and conditioned anxiogenic-like responses to a cannabinoid agonist in the social interaction test.

  3. Effects of cannabinoid receptor agonist and antagonist ligands on production of inflammatory cytokines and anti-inflammatory interleukin-10 in endotoxemic mice.

    Science.gov (United States)

    Smith, S R; Terminelli, C; Denhardt, G

    2000-04-01

    Previous studies have shown that mice primed with Corynebacterium parvum produce higher levels of inflammatory cytokines than unprimed mice upon challenge with lipopolysaccharide (LPS). Herein, we describe experiments in which two cannabinoid (CB) agonists, WIN 55212-2 [(R)-(+)-[2, 3-dihydro-5-methyl-3-[(4-morpholinyl)methyl]pyrrolo[1,2,3-de]1, 4-benzoxazin-6-yl](1-naphthyl)methanone) and HU-210 [(-)-11-hydroxy-delta(8) tetrahydrocannabinol-dimethylheptyl], were examined for their effects on LPS-induced cytokines in C. parvum-primed and unprimed mice. These agonists have been reported to bind selectively to the CB2 and CB1 receptor subtypes, respectively. WIN 55212-2 (3.1-50 mg/kg i.p.) and HU-210 (0.05-0.4 mg/kg i.p.) decreased serum tumor necrosis factor-alpha and interleukin-12 (IL-12) and increased IL-10 when administered to mice before LPS. The drugs also protected C. parvum mice (but not unprimed mice) against the lethal effects of LPS. The protection afforded to C. parvum mice could not be attributed to the higher levels of IL-10 present in these mice after agonist treatment. The WIN 55212-2- and HU-210-mediated changes in the responsiveness of mice to LPS were antagonized by SR141716A [N-(piperdin-1-yl)-5-(4-chloropheny)-1-(2, 4-dichloropheny)-4-methyl-1H-pyrazole-3-carboxamide hydrochloride], a selective CB1 receptor antagonist, but not by SR144528 [N-[(1S)-endo-1,3,3-trimethylbicyclo[2.2. 1]heptan-2-yl]5-(4-choro-3-methylphenyl)-1-(4-methylbenzyl)p yrazole-3 -carboxamide], a selective antagonist at the CB2 receptor. Therefore, both CB agonists modulated LPS responses through the CB1 receptor. Surprisingly, SR141716A itself modulated cytokine responses in a manner identical with that of WIN 55212-2 and HU-210 when administered alone to mice. The agonist-like effects of SR141716A, which were more striking in unprimed than in primed mice, suggested that the antagonist also could function as a partial agonist at the CB1 receptor. Our findings indicate a role

  4. Effects of glucagon-like peptide-1 receptor stimulation and blockade on food consumption and body weight in rats treated with a cannabinoid CB1 receptor agonist WIN 55,212-2

    Science.gov (United States)

    Radziszewska, Elżbieta; Bojanowska, Ewa

    2013-01-01

    Background Glucagon-like peptide-1 (GLP-1) and endocannabinoids are involved in appetite control. Recently we have demonstrated that cannabinoid (CB)1 receptor antagonist and GLP-1 receptor agonist synergistically suppress food intake in the rat. The aim of the present study was to determine the effects of GLP-1 receptor stimulation or blockade on feeding behavior in rats treated with WIN 55,212-2, a CB1 receptor agonist. Material/Methods Experiments were performed on adult male Wistar rats. In the first experiment the effects of increasing doses (0.5–4.0 mg/kg) of WIN 55,212-2 injected intraperitoneally on 24-hour food consumption were tested. In further experiments a GLP-1 receptor antagonist, exendin (9-39), and WIN 55,212-2 or a GLP-1 receptor agonist, exendin-4, and WIN 55,212-2 were injected intraperitoneally at subthreshold doses (that alone did not change food intake and body weight) to investigate whether these agents may interact to affect food intake in rats. Results WIN 55,212-2 administered at low doses (0.5–2 mg/kg) did not markedly change 24-hour food consumption; however, at the highest dose, daily food intake was inhibited. Combined administration of WIN 55,212-2 and exendin (9-39) did not change the amount of food consumed compared to either the control group or to each agent injected alone. Combined injection of WIN 55,212-2 and exendin-4 at subthreshold doses resulted in a significant decrease in food intake and body weight in rats. Conclusions Stimulation of the peripheral CB1 receptor by its agonist WIN 55,212-2 can induce anorexigenic effects or potentiate, even at a subthreshold dose, the effects of exendin-4, a known anorectic agent. Hence, this dual action of the cannabinoid system should be considered in the medical use of CB1 agonists. PMID:23291632

  5. Therapeutic Potentials and uses of Cannabinoid Agonists in Health and Disease Conditions

    Directory of Open Access Journals (Sweden)

    A.O. Ibegbu

    2012-04-01

    Full Text Available Cannabis and its derivatives have great therapeutic potential and have been used for centuries for medicinal purposes. The side effects of cannabinoids include euphoric mood changes, acute psychotic episodes, initiation and exacerbation of schizophrenic psychosis in predisposed persons, impaired cognitive and psychomotor performance, tachycardia and hypotension. The production of complex behavioural effects by cannabinoids are mediated by cannabinoid receptors (CB1 and CB2 and by interactions with other neurochemical systems. It has been shown that the therapeutic and physiological effects of cannabinoids are dependent upon whether the administration is acute or chronic and on the route of administration. The physiological effects of cannabis and its derivatives include: reduction in psychomotor coordination and performance, alterations in thermoregulation, endocrine and reproductive functions and gut motility. There is also evidence of agonist selectivity for CB1 receptors coupled to different subtypes of Gi proteins or to Gi versus Go proteins. Cannabinoid-activated receptors distinct from CB1 or CB2 exist in the central nervous system. Cannabinoids are known to inhibit GABA-mediated inhibitory postsynaptic currents in the hippocampus via a presynaptic action at CB1 receptors located on GABAergic terminals. CB1 receptors have also been implicated in the inhibition of glutamatergic excitatory postsynaptic currents. The synthetic cannabinoid, Win 55,212-2, a mixed CB1-CB2 cannabinoid receptor agonist, was found to attenuate hyperalgesia in a rat model of neuropathic pain and suppress opioid-induced emesis in ferrets.

  6. Cannabinoid receptor localization in brain

    Energy Technology Data Exchange (ETDEWEB)

    Herkenham, M.; Lynn, A.B.; Little, M.D.; Johnson, M.R.; Melvin, L.S.; de Costa, B.R.; Rice, K.C. (National Institute of Mental Health, Bethesda, MD (USA))

    1990-03-01

    (3H)CP 55,940, a radiolabeled synthetic cannabinoid, which is 10-100 times more potent in vivo than delta 9-tetrahydrocannabinol, was used to characterize and localize a specific cannabinoid receptor in brain sections. The potencies of a series of natural and synthetic cannabinoids as competitors of (3H)CP 55,940 binding correlated closely with their relative potencies in several biological assays, suggesting that the receptor characterized in our in vitro assay is the same receptor that mediates behavioral and pharmacological effects of cannabinoids, including human subjective experience. Autoradiography of cannabinoid receptors in brain sections from several mammalian species, including human, reveals a unique and conserved distribution; binding is most dense in outflow nuclei of the basal ganglia--the substantia nigra pars reticulata and globus pallidus--and in the hippocampus and cerebellum. Generally high densities in forebrain and cerebellum implicate roles for cannabinoids in cognition and movement. Sparse densities in lower brainstem areas controlling cardiovascular and respiratory functions may explain why high doses of delta 9-tetrahydrocannabinol are not lethal.

  7. Cannabinoid CB1 receptor agonists do not decrease, but may increase, acoustic trauma-induced tinnitus in rats

    Directory of Open Access Journals (Sweden)

    Yiwen eZheng

    2015-03-01

    Full Text Available Tinnitus has been suggested to arise from neuronal hyperactivity in auditory areas of the brain and anti-epileptic drugs are sometimes used to provide relief from tinnitus. Recently, the anti-epileptic properties of the cannabinoid drugs have gained increasing interest; however, the use of cannabinoids as a form of treatment for tinnitus is controversial. In the present study, we tested whether a combination of delta-9-tetrahydrocannabinol (delta-9-THC and cannabidiol (CBD, delivered in a 1:1 ratio, could affect tinnitus perception in a rat model of acoustic trauma-induced tinnitus. Following sham treatment or acoustic trauma, the animals were divided into the following groups: 1 sham (i.e. no acoustic trauma with vehicle treatment; 2 sham with drug treatment (i.e. delta-9-THC + CBD; 3 acoustic trauma-exposed exhibiting tinnitus, with drug treatment; and 4 acoustic trauma-exposed exhibiting no tinnitus, with drug treatment. The animals received either the vehicle or the cannabinoid drugs every day, 30 min before the tinnitus behavioural testing. Acoustic trauma caused a significant increase in the auditory brainstem response (ABR thresholds in the exposed animals, indicating hearing loss; however, there was a partial recovery over 6 months. Acoustic trauma did not always result in tinnitus; however among those that did exhibit tinnitus, some of them had tinnitus at multiple frequencies while others had it only at a single frequency. The cannabinoids significantly increased the number of tinnitus animals in the exposed-tinnitus group, but not in the sham group. The results suggest that cannabinoids may promote the development of tinnitus, especially when there is pre-existing hearing damage.

  8. (4-(Bis(4-fluorophenyl)methyl)piperazin-1-yl)(cyclohexyl)methanone hydrochloride (LDK1229): a new cannabinoid CB1 receptor inverse agonist from the class of benzhydryl piperazine analogs.

    Science.gov (United States)

    Mahmoud, Mariam M; Olszewska, Teresa; Liu, Hui; Shore, Derek M; Hurst, Dow P; Reggio, Patricia H; Lu, Dai; Kendall, Debra A

    2015-02-01

    Some inverse agonists of cannabinoid receptor type 1 (CB1) have been demonstrated to be anorectic antiobesity drug candidates. However, the first generation of CB1 inverse agonists, represented by rimonabant (SR141716A), otenabant, and taranabant, are centrally active, with a high level of psychiatric side effects. Hence, the discovery of CB1 inverse agonists with a chemical scaffold distinct from these holds promise for developing peripherally active CB1 inverse agonists with fewer side effects. We generated a new CB1 inverse agonist, (4-(bis(4-fluorophenyl)methyl)piperazin-1-yl)(cyclohexyl)methanone hydrochloride (LDK1229), from the class of benzhydryl piperazine analogs. This compound binds to CB1 more selectively than cannabinoid receptor type 2, with a Ki value of 220 nM. Comparable CB1 binding was also observed by analogs 1-[bis(4-fluorophenyl)methyl]-4-cinnamylpiperazine dihydrochloride (LDK1203) and 1-[bis(4-fluorophenyl)methyl]-4-tosylpiperazine hydrochloride (LDK1222), which differed by the substitution on the piperazine ring where the piperazine of LDK1203 and LDK1222 are substituted by an alkyl group and a tosyl group, respectively. LDK1229 exhibits efficacy comparable with SR141716A in antagonizing the basal G protein coupling activity of CB1, as indicated by a reduction in guanosine 5'-O-(3-thio)triphosphate binding. Consistent with inverse agonist behavior, increased cell surface localization of CB1 upon treatment with LDK1229 was also observed. Although docking and mutational analysis showed that LDK1229 forms similar interactions with the receptor as SR141716A does, the benzhydryl piperazine scaffold is structurally distinct from the first-generation CB1 inverse agonists. It offers new opportunities for developing novel CB1 inverse agonists through the optimization of molecular properties, such as the polar surface area and hydrophilicity, to reduce the central activity observed with SR141716A.

  9. Effect of Cannabinoid Receptor Activation on Spreading Depression

    OpenAIRE

    Kazemi, Hadi; Rahgozar, Mehdi; Speckmann, Erwin-Josef; Gorji, Ali

    2012-01-01

    Objective(s):The objective of this study was to evaluate the effect of cannabinoid on cortical spreading depression (CSD) in rat brain. Cannabis has been used for centuries for both symptomatic and prophylactic treatment of different types of headaches including migraine. CSD is believed to be a putative neuronal mechanism underlying migraine aura and subsequent pain. Materials and Methods:The effects of Delta9-tetrahydrocannabinol (THC), as well as, cannabinoid CB1 and CB2 receptor agonists ...

  10. Effects of WIN 55,212-2 (a non-selective cannabinoid CB1 and CB2 receptor agonist) on the protective action of various classical antiepileptic drugs in the mouse 6 Hz psychomotor seizure model

    OpenAIRE

    Florek-Luszczki, Magdalena; Wlaz, Aleksandra; Kondrat-Wrobel, Maria W.; Tutka, Piotr; Jarogniew J Luszczki

    2014-01-01

    The aim of this study was to characterize the influence of WIN 55,212-2 (WIN—a non-selective cannabinoid CB1 and CB2 receptor agonist) on the anticonvulsant effects of various classical antiepileptic drugs (clobazam, clonazepam, phenobarbital and valproate) in the mouse 6 Hz-induced psychomotor seizure model. Limbic (psychomotor) seizure activity was evoked in albino Swiss mice by a current (32 mA, 6 Hz, 3 s stimulus duration) delivered via ocular electrodes. Drug-related adverse effects were...

  11. CHROMENOPYRAZOLES: NON-PSYCHOACTIVE AND SELECTIVE CB1 CANNABINOID AGONISTS WITH PERIPHERAL ANTINOCICEPTIVE PROPERTIES

    Science.gov (United States)

    Cumella, Jose; Hernández-Folgado, Laura; Girón, Rocio; Sánchez, Eva; Morales, Paula; Hurst, Dow P.; Gómez-Cañas, Maria; Gómez-Ruiz, Maria; Pinto, Diana C. G. A.; Goya, Pilar; Reggio, Patricia H.; Martin, María Isabel; Fernández-Ruiz, Javier; Silva, Artur M. S.; Jagerovic, Nadine

    2014-01-01

    The unwanted psychoactive effects of cannabinoid receptor agonists have limited their development as medicines. These CB1 mediated side effects are due to the fact that CB1 receptors are largely expressed in the Central Nervous System (CNS). Since it is known that CB1 receptors are also located peripherally, there is a growing interest in targeting cannabinoid receptors located outside the brain. A library of chromenopyrazoles designed in analogy to the classical cannabinoid cannabinol were synthesized, characterized and tested for cannabinoid activity. Radiolabeled binding assays were used to determine their affinities at CB1 and CB2 receptors. Structural features required for CB1/CB2 affinity and selectivity were explored using molecular modeling. Within the chromenopyrazoles series, some of them showed to be selective CB1 ligands. These modeling studies suggest that CB1 full selectivity over CB2 can be accounted for the presence of a pyrazole ring in the structure. The functional activities of selected chromenopyrazoles were evaluated in isolated tissues. Behavioral tests, in vivo, were then carried on the most effective CB1 cannabinoid agonist (13a). Chromenopyrazole 13a did not induce modifications in any of the tested parameters on the mouse cannabinoid tetrad, discarding CNS-mediated effects. This lack of agonistic activity in the CNS suggests that it does not readily cross the blood-brain barrier. Moreover, compound 13a can induce antinociception in a peripheral model of orofacial pain in rat. Taking into account the negative results obtained in the hot plate test, it could be suggested that the antinociception induced by 13a in the orofacial test may be mediated through peripheral mechanisms. PMID:22302767

  12. Glutamate receptor agonists

    DEFF Research Database (Denmark)

    Vogensen, Stine Byskov; Greenwood, Jeremy R; Bunch, Lennart;

    2011-01-01

    The neurotransmitter (S)-glutamate [(S)-Glu] is responsible for most of the excitatory neurotransmission in the central nervous system. The effect of (S)-Glu is mediated by both ionotropic and metabotropic receptors. Glutamate receptor agonists are generally a-amino acids with one or more...... stereogenic centers due to strict requirements in the agonist binding pocket of the activated state of the receptor. By contrast, there are many examples of achiral competitive antagonists. The present review addresses how stereochemistry affects the activity of glutamate receptor ligands. The review focuses...

  13. The Study of Destructive Effects of Exposure to WIN 55212-2, an Agonist of Cannabinoid Receptor, during Pregnancy on CNS Function of Rats’ Offspring

    Directory of Open Access Journals (Sweden)

    Mohammad Shabani

    2011-08-01

    Full Text Available Introduction: Cannabinoid consumption including hashish and WIN55212-2 during pregnancy has destructive affect on the development of fetus and the performance of CNS. Method: WIN treated group received daily 0.5 or 1mg/kg WIN suspended in 1% tween 80 saline (s.c. at a volume of 1 ml/kg from days 5 to 20 of pregnancy. Third, fifth and seventh weeks after birth, the effects of maternal WIN consumption on infants body weight, mortality, histological changes, motor performance and memory function were assessed. Results: Prenatal WIN consumption associated with atrophy of cerebellum cortex in granular and Purkinje cells layers. WIN treatment of pregnant rats produced a significant decrease in the rearing frequency of the offspring, but significantly increased the grooming frequency at 22, 36 and 50 days of age. During the acquisition trials, approach latencies were not significantly different between all groups of rats (50 days old.When the trial was repeated 24 hours and seven days later (retention trial, the avoidance latencies of the WIN-exposed group were significantly shorter than those of control and sham animals. The mortality percent was increased significantly and litter size was decreased significantly in WIN (1mg/kg treated rats compared to the control, sham and WIN (0/5 mg/kg treatment groups. Conclusion: These findings suggest that prenatal exposure to WIN, cannabinoid agonist, induces possibly a long-term alteration on histological, motor performance and learning and memory parameters.

  14. Effect of delta(9)-tetrahydrocannabinol, a cannabinoid receptor agonist, on the triggering of transient lower oesophageal sphincter relaxations in dogs and humans

    NARCIS (Netherlands)

    H. Beaumont; J. Jensen; A. Carlsson; M. Ruth; A. Lehmann; G.E. Boeckxstaens

    2009-01-01

    Background and purpose: Transient lower oesophageal sphincter relaxations (TLESRs) are the main mechanism underlying gastro-oesophageal reflux and are a potential pharmacological treatment target. We evaluated the effect of the CB(1)/CB(2) receptor agonist Delta(9)-tetrahydrocannabinol (Delta(9)-THC

  15. Cannabinoid-receptor expression in human leukocytes.

    Science.gov (United States)

    Bouaboula, M; Rinaldi, M; Carayon, P; Carillon, C; Delpech, B; Shire, D; Le Fur, G; Casellas, P

    1993-05-15

    Marijuana and many of its constituent cannabinoids influence the central nervous system (CNS), probably through the cannabinoid receptor, which has recently been cloned in rat and human. While numerous reports have also described effects of cannabinoids on the immune system, the observation of both mRNA and cannabinoid receptor has hitherto been exclusively confined to the brain, a reported detection in the testis being the sole example of its presence at the periphery. Here we report the expression of the cannabinoid receptor on human immune tissues using a highly sensitive polymerase-chain-reaction-based method for mRNA quantification. We show that, although present in a much lower abundance than in brain, cannabinoid receptor transcripts are found in human spleen, tonsils and peripheral blood leukocytes. The distribution pattern displays important variations of the mRNA level for the cannabinoid receptor among the main human blood cell subpopulations. The rank order of mRNA levels in these cells is B cells > natural killer cells > or = polymorphonuclear neutrophils > or = T8 cells > monocytes > T4 cells. Cannabinoid-receptor mRNA, which is also found in monocytic, as well as T and B leukemia cell lines but not in Jurkat cells, presents a great diversity of expression on these cells as well, B-cell lines expressing a much higher level than T-cell lines. The cannabinoid receptor PCR products from leukocytes and brain are identical both in size and sequence suggesting a strong similarity between central and peripheral cannabinoid receptors. The expression of this receptor was demonstrated on membranes of the myelomonocytic U937 cells using the synthetic cannabinoid [3H]CP-55940 as ligand. The Kd determined from Scatchard analysis was 0.1 nM and the Bmax for membranes was 525 fmol/mg protein. The demonstration of cannabinoid-receptor expression at both mRNA and protein levels on human leukocytes provides a molecular basis for cannabinoid action on these cells. PMID

  16. Antagonistic and inverse agonistic effect of M J15 on cannabinoid receptors Ⅰ%MJ15对大麻素Ⅰ型受体的阻滞及反相激动作用的研究

    Institute of Scientific and Technical Information of China (English)

    曹宁; 杨洋; 周晓棉; 徐成; 王莉莉

    2011-01-01

    Objective: To observe the antagonistic and inverse agonistic effect of MJ15 on cannabinoid receptors Ⅰ (CB1). Methods: The samples of the ileum smooth muscle isolated from guinea pigs and vas deferens isolated from mice were put into the Magnus' bath, and the contractive activities were investigated. Results: The CB1 receptor agonist WIN55212-2 ( 10 - 10 ~ 10 - 6 mol · L - 1 ) inhibited electrically induced contraction of mouse vas deferens; the concentration-dependency was significant. The concentration-response curse was completely inhibited by SR141716A and MJ15(l0-7 mol· L-1). WIN55212-2 inhibited contraction of mouse vas deferens and guinea pig ileum smooth muscle; while SR141716A and MJ15 accelerated the contraction. Conclusion: MJ15 is an antagonist of CB1 receptor with inverse agonistic activity.%目的:观察MJ15对大麻素Ⅰ型(cannabinoid receptors Ⅰ,CB1)受体的阻滞及反相激动作用.方法:制备小鼠输精管和豚鼠回肠平滑肌的离体标本,观察CB1受体激动剂WIN55212-2以及阻滞剂利莫那班(SR141716A)和MJ15对其收缩特性的影响.结果:CB1受体激动剂WIN55212-2(10-10~10-6 mol·L-1)可抑制电刺激所引起小鼠输精管的收缩作用,呈现明显的剂量依赖性,而SR141716A和MJ15(10-7mol·L-1)能阻滞WIN55212-2的抑制作用;CB1受体激动剂WIN55212-2可抑制豚鼠回肠和小鼠输精管平滑肌的收缩,而SR141716A和MJ15能促进豚鼠回肠和小鼠输精管平滑肌的收缩.结论:MJ15是CB1受体的阻滞剂,同时具有反相激动作用.

  17. Biodistribution and dosimetry in humans of two inverse agonists to image cannabinoid CB{sub 1} receptors using positron emission tomography

    Energy Technology Data Exchange (ETDEWEB)

    Terry, Garth E. [National Institute of Mental Health, Molecular Imaging Branch, Bethesda, MD (United States); Karolinska Institutet, Department of Clinical Neuroscience, Psychiatry Section, Stockholm (Sweden); Hirvonen, Jussi; Liow, Jeih-San; Seneca, Nicholas; Morse, Cheryl L.; Pike, Victor W.; Innis, Robert B. [National Institute of Mental Health, Molecular Imaging Branch, Bethesda, MD (United States); Tauscher, Johannes T.; Schaus, John M.; Phebus, Lee; Felder, Christian C. [Lilly Research Laboratories, Lilly Corporate Center, Indianapolis, IN (United States); Halldin, Christer [Karolinska Institutet, Department of Clinical Neuroscience, Psychiatry Section, Stockholm (Sweden)

    2010-08-15

    Cannabinoid subtype 1 (CB{sub 1}) receptors are found in nearly every organ in the body, may be involved in several neuropsychiatric and metabolic disorders, and are therefore an active target for pharmacotherapy and biomarker development. We recently reported brain imaging of CB{sub 1} receptors with two PET radioligands: {sup 11}C-MePPEP and {sup 18}F-FMPEP-d{sub 2}. Here we describe the biodistribution and dosimetry estimates for these two radioligands. Seven healthy subjects (four men and three women) underwent whole-body PET scans for 120 min after injection with {sup 11}C-MePPEP. Another seven healthy subjects (two men and five women) underwent whole-body PET scans for 300 min after injection with {sup 18}F-FMPEP-d{sub 2}. Residence times were acquired from regions of interest drawn on tomographic images of visually identifiable organs for both radioligands and from radioactivity excreted in urine for {sup 18}F-FMPEP-d{sub 2}. The effective doses of {sup 11}C-MePPEP and {sup 18}F-FMPEP-d{sub 2} are 4.6 and 19.7 {mu}Sv/MBq, respectively. Both radioligands demonstrated high uptake of radioactivity in liver, lung, and brain shortly after injection and accumulated radioactivity in bone marrow towards the end of the scan. After injection of {sup 11}C-MePPEP, radioactivity apparently underwent hepatobiliary excretion only, while radioactivity from {sup 18}F-FMPEP-d{sub 2} showed both hepatobiliary and urinary excretion. {sup 11}C-MePPEP and {sup 18}F-FMPEP-d{sub 2} yield an effective dose similar to other PET radioligands labeled with either {sup 11}C or {sup 18}F. The high uptake in brain confirms the utility of these two radioligands to image CB{sub 1} receptors in brain, and both may also be useful to image CB{sub 1} receptors in the periphery. (orig.)

  18. Cannabinoid receptor activation shifts temporally engendered patterns of dopamine release.

    Science.gov (United States)

    Oleson, Erik B; Cachope, Roger; Fitoussi, Aurelie; Tsutsui, Kimberly; Wu, Sharon; Gallegos, Jacqueline A; Cheer, Joseph F

    2014-05-01

    The ability to discern temporally pertinent environmental events is essential for the generation of adaptive behavior in conventional tasks, and our overall survival. Cannabinoids are thought to disrupt temporally controlled behaviors by interfering with dedicated brain timing networks. Cannabinoids also increase dopamine release within the mesolimbic system, a neural pathway generally implicated in timing behavior. Timing can be assessed using fixed-interval (FI) schedules, which reinforce behavior on the basis of time. To date, it remains unknown how cannabinoids modulate dopamine release when responding under FI conditions, and for that matter, how subsecond dopamine release is related to time in these tasks. In the present study, we hypothesized that cannabinoids would accelerate timing behavior in an FI task while concurrently augmenting a temporally relevant pattern of dopamine release. To assess this possibility, we measured subsecond dopamine concentrations in the nucleus accumbens while mice responded for food under the influence of the cannabinoid agonist WIN 55,212-2 in an FI task. Our data reveal that accumbal dopamine concentrations decrease proportionally to interval duration--suggesting that dopamine encodes time in FI tasks. We further demonstrate that WIN 55,212-2 dose-dependently increases dopamine release and accelerates a temporal behavioral response pattern in a CB1 receptor-dependent manner--suggesting that cannabinoid receptor activation modifies timing behavior, in part, by augmenting time-engendered patterns of dopamine release. Additional investigation uncovered a specific role for endogenous cannabinoid tone in timing behavior, as elevations in 2-arachidonoylglycerol, but not anandamide, significantly accelerated the temporal response pattern in a manner akin to WIN 55,212-2. PMID:24345819

  19. Stimulation of cannabinoid receptor 2 (CB2 suppresses microglial activation

    Directory of Open Access Journals (Sweden)

    Fernandez Francisco

    2005-12-01

    Full Text Available Abstract Background Activated microglial cells have been implicated in a number of neurodegenerative disorders, including Alzheimer's disease (AD, multiple sclerosis (MS, and HIV dementia. It is well known that inflammatory mediators such as nitric oxide (NO, cytokines, and chemokines play an important role in microglial cell-associated neuron cell damage. Our previous studies have shown that CD40 signaling is involved in pathological activation of microglial cells. Many data reveal that cannabinoids mediate suppression of inflammation in vitro and in vivo through stimulation of cannabinoid receptor 2 (CB2. Methods In this study, we investigated the effects of a cannabinoid agonist on CD40 expression and function by cultured microglial cells activated by IFN-γ using RT-PCR, Western immunoblotting, flow cytometry, and anti-CB2 small interfering RNA (siRNA analyses. Furthermore, we examined if the stimulation of CB2 could modulate the capacity of microglial cells to phagocytise Aβ1–42 peptide using a phagocytosis assay. Results We found that the selective stimulation of cannabinoid receptor CB2 by JWH-015 suppressed IFN-γ-induced CD40 expression. In addition, this CB2 agonist markedly inhibited IFN-γ-induced phosphorylation of JAK/STAT1. Further, this stimulation was also able to suppress microglial TNF-α and nitric oxide production induced either by IFN-γ or Aβ peptide challenge in the presence of CD40 ligation. Finally, we showed that CB2 activation by JWH-015 markedly attenuated CD40-mediated inhibition of microglial phagocytosis of Aβ1–42 peptide. Taken together, these results provide mechanistic insight into beneficial effects provided by cannabinoid receptor CB2 modulation in neurodegenerative diseases, particularly AD.

  20. Cannabinoid receptor 2 as a potential therapeutic target in rheumatoid arthritis

    OpenAIRE

    Fukuda, Shin; Kohsaka, Hitoshi; Takayasu, Aiko; Yokoyama, Waka; Miyabe, Chie; Miyabe, Yoshishige; Harigai, Masayoshi; Miyasaka, Nobuyuki; Nanki, Toshihiro

    2014-01-01

    Background Some of cannabinoids, which are chemical compounds contained in marijuana, are immunosuppressive. One of the receptors, CB receptor 1 (CB1), is expressed predominantly by the cells in the central nervous system, whereas CB receptor 2 (CB2) is expressed primarily by immune cells. Theoretically, selective CB2 agonists should be devoid of psychoactive effects. In this study, we investigated therapeutic effects of a selective CB2 agonist on arthritis. Methods The expression of CB2 was ...

  1. Derivados de cromenopirazoles como ligandos de receptores de cannabinoides

    OpenAIRE

    Jagerovic, Nadine; Cumella Montánchez, José María; Goya, Pilar; Fernández, Javier; Gómez, María; Rodríguez, Patricia

    2009-01-01

    Derivados de cromenopirazoles como ligandos de receptores de cannabinoides. Compuestos derivados de cromenopirazoles que son ligandos de receptores de cannabinoides, su uso para la fabricación de un medicamento, uso de este medicamento para el tratamiento y/o la prevención de trastornos asociados a los receptores de cannabinoides, uso de dicho compuesto como reactivo en ensayos biológicos relacionados con receptores de cannabinoides y procedimiento de obtención de l...

  2. Peripheral cannabinoid receptor, CB2, regulates bone mass

    Science.gov (United States)

    Ofek, Orr; Karsak, Meliha; Leclerc, Nathalie; Fogel, Meirav; Frenkel, Baruch; Wright, Karen; Tam, Joseph; Attar-Namdar, Malka; Kram, Vardit; Shohami, Esther; Mechoulam, Raphael; Zimmer, Andreas; Bab, Itai

    2006-01-01

    The endogenous cannabinoids bind to and activate two G protein-coupled receptors, the predominantly central cannabinoid receptor type 1 (CB1) and peripheral cannabinoid receptor type 2 (CB2). Whereas CB1 mediates the cannabinoid psychotropic, analgesic, and orectic effects, CB2 has been implicated recently in the regulation of liver fibrosis and atherosclerosis. Here we show that CB2-deficient mice have a markedly accelerated age-related trabecular bone loss and cortical expansion, although cortical thickness remains unaltered. These changes are reminiscent of human osteoporosis and may result from differential regulation of trabecular and cortical bone remodeling. The CB2–/– phenotype is also characterized by increased activity of trabecular osteoblasts (bone-forming cells), increased osteoclast (the bone-resorbing cell) number, and a markedly decreased number of diaphyseal osteoblast precursors. CB2 is expressed in osteoblasts, osteocytes, and osteoclasts. A CB2-specific agonist that does not have any psychotropic effects enhances endocortical osteoblast number and activity and restrains trabecular osteoclastogenesis, apparently by inhibiting proliferation of osteoclast precursors and receptor activator of NF-κB ligand expression in bone marrow-derived osteoblasts/stromal cells. The same agonist attenuates ovariectomy-induced bone loss and markedly stimulates cortical thickness through the respective suppression of osteoclast number and stimulation of endocortical bone formation. These results demonstrate that the endocannabinoid system is essential for the maintenance of normal bone mass by osteoblastic and osteoclastic CB2 signaling. Hence, CB2 offers a molecular target for the diagnosis and treatment of osteoporosis, the most prevalent degenerative disease in developed countries. PMID:16407142

  3. Dual intracellular signaling pathways mediated by the human cannabinoid CB1 receptor.

    Science.gov (United States)

    Calandra, B; Portier, M; Kernéis, A; Delpech, M; Carillon, C; Le Fur, G; Ferrara, P; Shire, D

    1999-06-25

    It has long been established that the cannabinoid CB1 receptor transduces signals through a pertussis toxin-sensitive Gi/Go inhibitory pathway. Although there have been reports that the cannabinoid CB1 receptor can also mediate an increase in cyclic AMP levels, in most cases the presence of an adenylyl cyclase costimulant or the use of very high amounts of agonist was necessary. Here, we present evidence for dual coupling of the cannabinoid CB receptor to the classical pathway and to a pertussis toxin-insensitive adenylyl cyclase stimulatory pathway initiated with low quantities of agonist in the absence of any costimulant. Treatment of Chinese hamster ovary (CHO) cells expressing the cannabinoid CB1 receptor with the cannabinoid CP 55,940, {(-)-cis-3-[2-hydroxy-4-(1,1-dimethylheptyl)phenyl]-trans-4-(3-hyd roxypropyl) cyclohexan-1-ol} resulted in cyclic AMP accumulation in a dose-response manner, an accumulation blocked by the cannabinoid CB1 receptor-specific antagonist SR 141716A, {N-(piperidin-1-yl)-5-(4-chlorophenyl)-1-(2,4-dichlorophenyl)-4-me thyl-1H-pyrazole-3-carboxamide hydrochloride}. In CHO cells coexpressing the cannabinoid CB1 receptor and a cyclic AMP response element (CRE)-luciferase reporter gene system, CP 55,940 induced luciferase expression by a pathway blocked by the protein kinase A inhibitor N-[2-(p-bromocinnamylamino)ethyl]-5-isoquinolinesulfonamide hydrochloride (H-89). Under the same conditions the peripheral cannabinoid CB2 receptor proved to be incapable of inducing cAMP accumulation or luciferase activity. This incapacity allowed us to study the luciferase activation mediated by CB /CB2 chimeric constructs, from which we determined that the first and second internal loop regions of the cannabinoid CB1 receptor were involved in transducing the pathway leading to luciferase gene expression. PMID:10422789

  4. WIN 55,212-2, agonist of cannabinoid receptors, prevents amyloid β1-42 effects on astrocytes in primary culture.

    Directory of Open Access Journals (Sweden)

    Diana Aguirre-Rueda

    Full Text Available Alzheimer's disease (AD, a neurodegenerative illness involving synaptic dysfunction with extracellular accumulation of Aβ1-42 toxic peptide, glial activation, inflammatory response and oxidative stress, can lead to neuronal death. Endogenous cannabinoid system is implicated in physiological and physiopathological events in central nervous system (CNS, and changes in this system are related to many human diseases, including AD. However, studies on the effects of cannabinoids on astrocytes functions are scarce. In primary cultured astrocytes we studied cellular viability using MTT assay. Inflammatory and oxidative stress mediators were determined by ELISA and Western-blot techniques both in the presence and absence of Aβ1-42 peptide. Effects of WIN 55,212-2 (a synthetic cannabinoid on cell viability, inflammatory mediators and oxidative stress were also determined. Aβ1-42 diminished astrocytes viability, increased TNF-α and IL-1β levels and p-65, COX-2 and iNOS protein expression while decreased PPAR-γ and antioxidant enzyme Cu/Zn SOD. WIN 55,212-2 pretreatment prevents all effects elicited by Aβ1-42. Furthermore, cannabinoid WIN 55,212-2 also increased cell viability and PPAR-γ expression in control astrocytes. In conclusion cannabinoid WIN 55,212-2 increases cell viability and anti-inflammatory response in cultured astrocytes. Moreover, WIN 55,212-2 increases expression of anti-oxidant Cu/Zn SOD and is able to prevent inflammation induced by Aβ1-42 in cultured astrocytes. Further studies would be needed to assess the possible beneficial effects of cannabinoids in Alzheimer's disease patients.

  5. Metabolites of 5F-AKB-48, a synthetic cannabinoid receptor agonist, identified in human urine and liver microsomal preparations using liquid chromatography high-resolution mass spectrometry

    DEFF Research Database (Denmark)

    Holm, Niels Bjerre; Pedersen, Anders Just; Dalsgaard, Petur Weihe;

    2015-01-01

    -fluoropentylindazole moiety, dealkylation of the N-fluoropentyl side chain, and oxidative loss of fluorine as well as combinations thereof. The results were compared to human liver microsomal (HLM) incubations, which predominantly showed time-dependent formation of mono-, di-, and trihydroxylated metabolites having....... This compound deviates from earlier JHW-type synthetic cannabinoids by having an indazole ring connected to an adamantyl group via a carboxamide linkage. Synthetic cannabinoids are completely metabolized, and identification of the metabolites is thus crucial when using urine as the sample matrix. Using...

  6. Chronic co-administration of the cannabinoid receptor agonist WIN55,212-2 during puberty or adulthood reverses 3,4 methylenedioxymetamphetamine (MDMA)-induced deficits in recognition memory but not in effort-based decision making.

    Science.gov (United States)

    Schulz, Sybille; Becker, Thorsten; Nagel, Ulrich; von Ameln-Mayerhofer, Andreas; Koch, Michael

    2013-05-01

    Cannabis and 3,4 methylenedioxymetamphetamine (MDMA, "ecstasy") are the most frequently combined illegal drugs among young adults in western societies. This study examined the effects of chronic co-administration of the cannabinoid receptor agonist WIN55,212-2 (WIN) and MDMA on working memory and effort-based decision making in rats. Treatment consisted of MDMA (7.5 mg/kg), WIN (1.2 mg/kg), a combination of these substances (MDMA+WIN) or vehicle over a period of 25 days during puberty (PD40-65) or adulthood (PD80-105). Ten days after the last treatment, WIN reversed MDMA-induced working memory deficits in the object recognition test in animals treated during adulthood or puberty, but had no influence on impairment of adult rats in the effort-based T-maze task. No differences were observed between groups of pubertally treated rats in the decision making task. During a subsequent acute drug challenge MDMA and MDMA+WIN decreased high reward choices in both age groups, indicating MDMA-induced cost-aversive choice. Differential long-term interactions on the neuronal level in the hippocampus and MDMA-induced disturbances in cortico-limbic connections are suggested. PMID:23541493

  7. [Plants' materials and synthetic agonists of cannabinoid receptors use as a substitute of Marihuana, appearing in a current forensic toxicology practice of evidence materials].

    Science.gov (United States)

    Geppert, Bogna; Tezyk, Artur; Florek, Ewa; Zaba, Czesław

    2010-01-01

    Cannabis sativa species Indica (Marihuana) is nowadays one of the most common plant drug, with psychoactive activity, presently appearing on the illegal market in Poland. It is reported that frequency of securing evidential materials so called substitute of Marihuana, is growing rapidly during the last few years. The substitutes of Marihuana occurring on the market are of natural or synthetic origins, for example different species of raw plants' materials having action similar to Cannabis or raw plants' materials with no psychoactive properities but with an addition of components so called synthetic cannabinoids. The review presents recent developments in drug market and current problems of forensic toxicology on the example of Marihuana.

  8. Cannabinoid CB2 receptor-mediated anti-nociception in models of acute and chronic pain.

    Science.gov (United States)

    Jhaveri, Maulik D; Sagar, Devi R; Elmes, Steven J R; Kendall, David A; Chapman, Victoria

    2007-08-01

    The endocannabinoid system consists of cannabinoid CB(1) and CB(2) receptors, endogenous ligands and their synthesising/metabolising enzymes. Cannabinoid receptors are present at key sites involved in the relay and modulation of nociceptive information. The analgesic effects of cannabinoids have been well documented. The usefulness of nonselective cannabinoid agonists can, however, be limited by psychoactive side effects associated with activation of CB(1) receptors. Following the recent evidence for CB(2) receptors existing in the nervous system and reports of their up-regulation in chronic pain states and neurodegenerative diseases, much research is now aimed at shedding light on the role of the CB(2) receptor in human disease. Recent studies have demonstrated anti-nociceptive effects of selective CB(2) receptor agonists in animal models of pain in the absence of CNS side effects. This review focuses on the analgesic potential of CB(2) receptor agonists for inflammatory, post-operative and neuropathic pain states and discusses their possible sites and mechanisms of action.

  9. MicroRNA let-7d is a target of cannabinoid CB1 receptor and controls cannabinoid signaling.

    Science.gov (United States)

    Chiarlone, Anna; Börner, Christine; Martín-Gómez, Laura; Jiménez-González, Ada; García-Concejo, Adrián; García-Bermejo, María L; Lorente, Mar; Blázquez, Cristina; García-Taboada, Elena; de Haro, Amador; Martella, Elisa; Höllt, Volker; Rodríguez, Raquel; Galve-Roperh, Ismael; Kraus, Jürgen; Guzmán, Manuel

    2016-09-01

    Cannabinoid CB1 receptor, the molecular target of endocannabinoids and cannabis active components, is one of the most abundant metabotropic receptors in the brain. Cannabis is widely used for both recreational and medicinal purposes. Despite the ever-growing fundamental roles of microRNAs in the brain, the possible molecular connections between the CB1 receptor and microRNAs are surprisingly unknown. Here, by using reporter gene constructs that express interaction sequences for microRNAs in human SH-SY5Y neuroblastoma cells, we show that CB1 receptor activation enhances the expression of several microRNAs, including let-7d. This was confirmed by measuring hsa-let-7d expression levels. Accordingly, knocking-down CB1 receptor in zebrafish reduced dre-let-7d levels, and knocking-out CB1 receptor in mice decreased mmu-let-7d levels in the cortex, striatum and hippocampus. Conversely, knocking-down let-7d increased CB1 receptor mRNA expression in zebrafish, SH-SY5Y cells and primary striatal neurons. Likewise, in primary striatal neurons chronically exposed to a cannabinoid or opioid agonist, a let-7d-inhibiting sequence facilitated not only cannabinoid or opioid signaling but also cannabinoid/opioid cross-signaling. Taken together, these findings provide the first evidence for a bidirectional link between the CB1 receptor and a microRNA, namely let-7d, and thus unveil a new player in the complex process of cannabinoid action.

  10. MicroRNA let-7d is a target of cannabinoid CB1 receptor and controls cannabinoid signaling.

    Science.gov (United States)

    Chiarlone, Anna; Börner, Christine; Martín-Gómez, Laura; Jiménez-González, Ada; García-Concejo, Adrián; García-Bermejo, María L; Lorente, Mar; Blázquez, Cristina; García-Taboada, Elena; de Haro, Amador; Martella, Elisa; Höllt, Volker; Rodríguez, Raquel; Galve-Roperh, Ismael; Kraus, Jürgen; Guzmán, Manuel

    2016-09-01

    Cannabinoid CB1 receptor, the molecular target of endocannabinoids and cannabis active components, is one of the most abundant metabotropic receptors in the brain. Cannabis is widely used for both recreational and medicinal purposes. Despite the ever-growing fundamental roles of microRNAs in the brain, the possible molecular connections between the CB1 receptor and microRNAs are surprisingly unknown. Here, by using reporter gene constructs that express interaction sequences for microRNAs in human SH-SY5Y neuroblastoma cells, we show that CB1 receptor activation enhances the expression of several microRNAs, including let-7d. This was confirmed by measuring hsa-let-7d expression levels. Accordingly, knocking-down CB1 receptor in zebrafish reduced dre-let-7d levels, and knocking-out CB1 receptor in mice decreased mmu-let-7d levels in the cortex, striatum and hippocampus. Conversely, knocking-down let-7d increased CB1 receptor mRNA expression in zebrafish, SH-SY5Y cells and primary striatal neurons. Likewise, in primary striatal neurons chronically exposed to a cannabinoid or opioid agonist, a let-7d-inhibiting sequence facilitated not only cannabinoid or opioid signaling but also cannabinoid/opioid cross-signaling. Taken together, these findings provide the first evidence for a bidirectional link between the CB1 receptor and a microRNA, namely let-7d, and thus unveil a new player in the complex process of cannabinoid action. PMID:27179908

  11. Derivados de cromenopirazoles como ligandos de receptores de cannabinoides.

    OpenAIRE

    Jagerovic, Nadine; Cumella Montánchez, José María; Goya, Pilar; Fernández, Javier; Gómez, María; Rodríguez, Patricia

    2009-01-01

    [ES] Compuestos derivados de cromenopirazoles que son ligandos de receptores de cannabinoides, su uso para la fabricación de un medicamento, uso de este medicamento para el tratamiento y/o la prevención de trastornos asociados a los receptores de cannabinoides, uso de dicho compuesto como reactivo en ensayos biológicos relacionados con receptores de cannabinoides y procedimiento de obtención de los mismos.

  12. Cannabinoid receptor CB2 modulates axon guidance

    DEFF Research Database (Denmark)

    Duff, Gabriel; Argaw, Anteneh; Cecyre, Bruno;

    2013-01-01

    Navigation of retinal projections towards their targets is regulated by guidance molecules and growth cone transduction mechanisms. Here, we present in vitro and in vivo evidences that the cannabinoid receptor 2 (CB2R) is expressed along the retino-thalamic pathway and exerts a modulatory action ...... CB2R's implication in retinothalamic development. Overall, this study demonstrates that the contribution of endocannabinoids to brain development is not solely mediated by CB1R, but also involves CB2R....

  13. Emerging GLP-1 receptor agonists

    DEFF Research Database (Denmark)

    Lund, Asger; Knop, Filip K; Vilsbøll, Tina

    2011-01-01

    Introduction: Recently, glucagon-like peptide-1 receptor (GLP-1R) agonists have become available for the treatment of type 2 diabetes. These agents exploit the physiological effects of GLP-1, which is able to address several of the pathophysiological features of type 2 diabetes. GLP-1R agonists...... presently available are administered once or twice daily, but several once-weekly GLP-1R agonists are in late clinical development. Areas covered: The present review aims to give an overview of the clinical data on the currently available GLP-1R agonists used for treatment of type 2 diabetes, exenatide and...... liraglutide, as well as the emerging GLP-1R agonists including the long-acting compounds. Expert opinion: An emerging therapeutic trend toward initial or early combination therapy with metformin- and incretin-based therapy is anticipated for patients with type 2 diabetes. GLP-1-based therapy has so far proven...

  14. Emerging GLP-1 receptor agonists

    DEFF Research Database (Denmark)

    Lund, Asger; Knop, Filip K; Vilsbøll, Tina

    2011-01-01

    Introduction: Recently, glucagon-like peptide-1 receptor (GLP-1R) agonists have become available for the treatment of type 2 diabetes. These agents exploit the physiological effects of GLP-1, which is able to address several of the pathophysiological features of type 2 diabetes. GLP-1R agonists...... presently available are administered once or twice daily, but several once-weekly GLP-1R agonists are in late clinical development. Areas covered: The present review aims to give an overview of the clinical data on the currently available GLP-1R agonists used for treatment of type 2 diabetes, exenatide...... and liraglutide, as well as the emerging GLP-1R agonists including the long-acting compounds. Expert opinion: An emerging therapeutic trend toward initial or early combination therapy with metformin- and incretin-based therapy is anticipated for patients with type 2 diabetes. GLP-1-based therapy has so far proven...

  15. Cannabinoid receptor-interacting protein 1a modulates CB1 receptor signaling and regulation.

    Science.gov (United States)

    Smith, Tricia H; Blume, Lawrence C; Straiker, Alex; Cox, Jordan O; David, Bethany G; McVoy, Julie R Secor; Sayers, Katherine W; Poklis, Justin L; Abdullah, Rehab A; Egertová, Michaela; Chen, Ching-Kang; Mackie, Ken; Elphick, Maurice R; Howlett, Allyn C; Selley, Dana E

    2015-04-01

    Cannabinoid CB1 receptors (CB1Rs) mediate the presynaptic effects of endocannabinoids in the central nervous system (CNS) and most behavioral effects of exogenous cannabinoids. Cannabinoid receptor-interacting protein 1a (CRIP1a) binds to the CB1R C-terminus and can attenuate constitutive CB1R-mediated inhibition of Ca(2+) channel activity. We now demonstrate cellular colocalization of CRIP1a at neuronal elements in the CNS and show that CRIP1a inhibits both constitutive and agonist-stimulated CB1R-mediated guanine nucleotide-binding regulatory protein (G-protein) activity. Stable overexpression of CRIP1a in human embryonic kidney (HEK)-293 cells stably expressing CB1Rs (CB1-HEK), or in N18TG2 cells endogenously expressing CB1Rs, decreased CB1R-mediated G-protein activation (measured by agonist-stimulated [(35)S]GTPγS (guanylyl-5'-[O-thio]-triphosphate) binding) in both cell lines and attenuated inverse agonism by rimonabant in CB1-HEK cells. Conversely, small-interfering RNA-mediated knockdown of CRIP1a in N18TG2 cells enhanced CB1R-mediated G-protein activation. These effects were not attributable to differences in CB1R expression or endocannabinoid tone because CB1R levels did not differ between cell lines varying in CRIP1a expression, and endocannabinoid levels were undetectable (CB1-HEK) or unchanged (N18TG2) by CRIP1a overexpression. In CB1-HEK cells, 4-hour pretreatment with cannabinoid agonists downregulated CB1Rs and desensitized agonist-stimulated [(35)S]GTPγS binding. CRIP1a overexpression attenuated CB1R downregulation without altering CB1R desensitization. Finally, in cultured autaptic hippocampal neurons, CRIP1a overexpression attenuated both depolarization-induced suppression of excitation and inhibition of excitatory synaptic activity induced by exogenous application of cannabinoid but not by adenosine A1 agonists. These results confirm that CRIP1a inhibits constitutive CB1R activity and demonstrate that CRIP1a can also inhibit agonist

  16. Effects of cannabinoids and their receptors on viral infections.

    Science.gov (United States)

    Tahamtan, Alireza; Tavakoli-Yaraki, Masoumeh; Rygiel, Tomasz P; Mokhtari-Azad, Talat; Salimi, Vahid

    2016-01-01

    Cannabinoids, the active ingredient in marijuana, and their derivatives have received remarkable attention in the last two decades because they can affect tumor growth and metastasis. There is a large body of evidence from in vivo and in vitro models showing that cannabinoids and their receptors influence the immune system, viral pathogenesis, and viral replication. The present study reviews current insights into the role of cannabinoids and their receptors on viral infections. The results reported here indicate that cannabinoids and their receptors have different sequels for viral infection. Although activation or inhibition of cannabinoid receptors in the majority of viral infections are proper targets for development of safe and effective treatments, caution is required before using pharmaceutical cannabinoids as a treatment agent for patients with viral infections. PMID:26059175

  17. Rational design, synthesis, and pharmacological properties of new 1,8-naphthyridin-2(1H)-on-3-carboxamide derivatives as highly selective cannabinoid-2 receptor agonists

    DEFF Research Database (Denmark)

    Manera, Clementina; Saccomanni, Giuseppe; Adinolfi, Barbara;

    2009-01-01

    The CB(2) receptor activation can be exploited for the treatment of diseases such as chronic pain and tumors of immune origin, devoid of psychotropic activity. On the basis of our already reported 1,8-naphthyridin-4(1H)-on-3-carboxamide derivatives, new 1,8-naphthyridin-2(1H)-on-3-carboxamide der...

  18. Functional responses to the cannabinoid agonist WIN 55,212-2 in neonatal rats of both genders: influence of weaning.

    Science.gov (United States)

    Borcel, Erika; Pérez-Alvarez, Laura; de Ceballos, María L; Ramirez, Belén G; Marco, Eva Maria; Fernández, Beatriz; Rubio, Marina; Guaza, Carmen; Viveros, Ma-Paz

    2004-07-01

    We have studied behavioural, biochemical and endocrine responses to the cannabinoid agonist WIN 55,212-2 (WIN) in neonatal rats, as well as the effects of weaning on such responses. We used preweanling rats (20 days of age), 25-day-old weaned rats (weaning at Day 22) and 25-day-old nonweaned rats of both sexes. The behavioural effects of WIN were assessed in the nociceptive tail immersion test and in the open field. We also analysed the effect of weaning on corticosterone responses to WIN (radioimmunoassay) as well as on WIN-stimulated [35S] GTPgammaS binding in periaqueductal grey (PAG) and striatum. The cannabinoid agonist induced a modest increase in pain thresholds, whereas the effect of the drug on open-field activity, particularly on vertical activity, was much more marked. The weaning process appeared to reduce the baseline nociceptive latencies of the female rats. No significant effect of weaning on the behavioural responses to WIN was found. However, the group of weaned females (but not males) showed a significantly reduced WIN-stimulated [35S] GTPgammaS binding in the striatum. The cannabinoid agonist significantly increased the corticosterone levels of 25-day-old rats with the effect being more marked in weaned than in nonweaned animals. The results suggest that the weaning process might produce some sexually dimorphic developmental changes in CB1 receptor function.

  19. Detecting constitutive activity and protean agonism at cannabinoid-2 receptor.

    Science.gov (United States)

    Beltramo, Massimiliano; Brusa, Rossella; Mancini, Isabella; Scandroglio, Paola

    2010-01-01

    Since the cannabinoid system is involved in regulating several physiological functions such as locomotor activity, cognition, nociception, food intake, and inflammatory reaction, it has been the subject of intense study. Research on the pharmacology of this system has enormously progressed in the last 20years. One intriguing aspect that emerged from this research is that cannabinoid receptors (CBs) express a high level of constitutive activity. Investigation on this particular aspect of receptor pharmacology has largely focused on CB1, the CB subtype highly expressed in several brain regions. More recently, research on constitutive activity on the other CB subtype, CB2, was stimulated by the increasing interest on its potential as target for the treatment of various pathologies (e.g., pain and inflammation). There are several possible implications of constitutive activity on the therapeutic action of both agonists and antagonists, and consequently, it is important to have valuable methods to study this aspect of CB2 pharmacology. In the present chapter, we describe three methods to study constitutive activity at CB2: two classical methods relying on the detection of changes in cAMP level and GTPγS binding and a new one based on cell impedance measurement. In addition, we also included a section on detection of protean agonism, which is an interesting pharmacological phenomenon strictly linked to constitutive activity. PMID:21036225

  20. The discovery of a cannabinoid receptor

    Energy Technology Data Exchange (ETDEWEB)

    Devane, W.A.

    1989-01-01

    A tritiated form of CP-55,940, a Pfizer cannabinoid analog that is 20- to 100-fold more potent than {Delta}{sup 9}-tetrahydrocannabinol in various in vivo and in vitro models of cannabimimetric activity, was used as the tool with which to probe for a cannabinoid receptor in rat cortical membranes. The bound and free ligand were successfully separated using a centrifugation assay. Specific binding was saturable, rapidly attained, and completely reversible. The K{sub D}'s derived from kinetic analysis of binding agreed well with the K{sub D}'s derived from saturation and displacement analysis. The ({sup 3}H)CP-55,940 binding site exhibited high affinity with a K{sub D} of 68 pM as determined by LIGAND analysis of homologous displacement studies. The ability of other cannabinoid drugs to displace ({sup 3}H)CP-55,940 binding correlated well with the potency of these drugs in in vivo and in vitro models of cannabimimetic activity. The K{sub i} of {Delta}{sup 9}-THC was 1.6 nM. Cannabidiol and cannabigerol, which both lack psychoactivity in man, displaced specific binding by less than 50% at 1 {mu}M.

  1. Regulation of MMP-9 by a WIN-binding site in the monocyte-macrophage system independent from cannabinoid receptors.

    Directory of Open Access Journals (Sweden)

    Svantje Tauber

    Full Text Available The cannabinoid system is known to be involved in the regulation of inflammatory processes. Therefore, drugs targeting cannabinoid receptors are considered as candidates for anti-inflammatory and tissue protective therapy. We demonstrated that the prototypical cannabinoid agonist R(+WIN55,212-2 (WIN reduced the secretion of matrix metalloproteinase-9 (MMP-9 in a murine model of cigarette-smoke induced lung inflammation. In experiments using primary cells and cell lines of the monocyte-macrophage-system we found that binding of the cannabinoid-receptor agonist WIN to a stereo-selective, specific binding site in cells of the monocyte-macrophage-system induced a significant down-regulation of MMP-9 secretion and disturbance of intracellular processing, which subsequently down-regulated MMP-9 mRNA expression via a ERK1/2-phosphorylation-dependent pathway. Surprisingly, the anti-inflammatory effect was independent from classical cannabinoid receptors. Our experiments supposed an involvement of TRPV1, but other yet unidentified sites are also possible. We conclude that cannabinoid-induced control of MMP-9 in the monocyte-macrophage system via a cannabinoid-receptor independent pathway represents a general option for tissue protection during inflammation, such as during lung inflammation and other diseases associated with inflammatory tissue damage.

  2. Activation of Cannabinoid CB2 receptors Reduces Hyperalgesia in an Experimental Autoimmune Encephalomyelitis Mouse Model of Multiple Sclerosis

    OpenAIRE

    Fu, Weisi; Taylor, Bradley K.

    2015-01-01

    Clinical trials investigating the analgesic efficacy of cannabinoids in multiple sclerosis have yielded mixed results, possibly due to psychotropic side effects mediated by cannabinoid CB1 receptors. We hypothesized that a CB2-specific agonist (JWH-133) would decrease hyperalgesia in an experimental autoimmune encephalomyelitis mouse model of multiple sclerosis. 4 weeks after induction of experimental autoimmune encephalomyelitis, we found that intrathecal administration of JWH-133 (10–100 μg...

  3. Type-2 cannabinoid receptors in neurodegeneration.

    Science.gov (United States)

    Bisogno, Tiziana; Oddi, Sergio; Piccoli, Alessandra; Fazio, Domenico; Maccarrone, Mauro

    2016-09-01

    Based on its wide expression in immune cells, type-2 cannabinoid (CB2) receptors were traditionally thought to act as "peripheral receptors" with an almost exclusively immunomodulatory function. However, their recent identification in mammalian brain areas, as well as in distinct neuronal cells, has opened the way to a re-consideration of CB2 signaling in the context of brain pathophysiology, synaptic plasticity and neuroprotection. To date, accumulated evidence from several independent preclinical studies has offered new perspectives on the possible involvement of CB2 signaling in brain and spinal cord traumatic injury, as well as in the most relevant neurodegenerative disorders like Alzheimer's disease, Parkinson's disease and Huntington's chorea. Here, we will review available information on CB2 in these disease conditions, along with data that support also its therapeutic potential to treat them. PMID:27450295

  4. Cannabinoid receptor stimulation increases motivation for nicotine and nicotine seeking.

    Science.gov (United States)

    Gamaleddin, Islam; Wertheim, Carrie; Zhu, Andy Z X; Coen, Kathleen M; Vemuri, Kiran; Makryannis, Alex; Goldberg, Steven R; Le Foll, Bernard

    2012-01-01

    The cannabinoid system appears to play a critical facilitative role in mediating the reinforcing effects of nicotine and relapse to nicotine-seeking behaviour in abstinent subjects based on the actions of cannabinoid (CB) receptor antagonists. However, the effects of CB receptor stimulation on nicotine self-administration and reinstatement have not been systematically studied. Here, we studied the effects of WIN 55,212-2, a CB1/2 agonist, on intravenous nicotine self-administration under fixed-ratio (FR) and progressive-ratio (PR) schedules of reinforcement in rats. The effects of WIN 55,212-2 on responding for food under similar schedules were also studied. In addition, the effects of WIN 55,212-2 on nicotine- and cue-induced reinstatement of nicotine seeking were also studied, as well as the effects of WIN 55,212-2 on nicotine discrimination. WIN 55,212-2 decreased nicotine self-administration under the FR schedule. However, co-administration of WIN 55,212-2 with nicotine decreased responding for food, which suggests that this effect was non-selective. In contrast, WIN 55,212-2 increased both nicotine self-administration and responding for food under the PR schedule, produced dose-dependent reinstatement of nicotine seeking, and enhanced the reinstatement effects of nicotine-associated cues. Some of these effects were reversed by the CB1 antagonist rimonabant, but not by the CB2 antagonist AM630. In the drug discrimination tests between saline and 0.4 mg/kg nicotine, WIN 55,212-2 produced no nicotine-like discriminative effects but significantly potentiated discriminative stimulus effects of nicotine at the low dose through a CB1-receptor-dependent mechanism. These findings indicate that cannabinoid CB1-receptor stimulation increases the reinforcing effects of nicotine and precipitates relapse to nicotine-seeking behaviour in abstinent subjects. Thus, modulating CB1-receptor signalling might have therapeutic value for treating nicotine dependence. PMID:21521420

  5. Constitutive cannabinoid 1 and mu opioid receptor activity in the ventral tegmental area: occurrence, function and therapeutic relevance

    NARCIS (Netherlands)

    Meye, F.J.

    2012-01-01

    Cannabinoid 1 receptors (CB1Rs) play a crucial role in regulating systems dedicated to processing rewards and emotions. It was known that in artificial systems, CB1Rs can exhibit activity that is independent of the typical agonist-driven form. However, it remained largely unclear whether this consti

  6. Synthetic Cannabinoids.

    Science.gov (United States)

    Mills, Brooke; Yepes, Andres; Nugent, Kenneth

    2015-07-01

    Synthetic cannabinoids (SCBs), also known under the brand names of "Spice," "K2," "herbal incense," "Cloud 9," "Mojo" and many others, are becoming a large public health concern due not only to their increasing use but also to their unpredictable toxicity and abuse potential. There are many types of SCBs, each having a unique binding affinity for cannabinoid receptors. Although both Δ-tetrahydrocannabinol (THC) and SCBs stimulate the same receptors, cannabinoid receptor 1 (CB1) and cannabinoid receptor 2 (CB2), studies have shown that SCBs are associated with higher rates of toxicity and hospital admissions than is natural cannabis. This is likely due to SCBs being direct agonists of the cannabinoid receptors, whereas THC is a partial agonist. Furthermore, the different chemical structures of SCBs found in Spice or K2 may interact in unpredictable ways to elicit previously unknown, and the commercial products may have unknown contaminants. The largest group of users is men in their 20s who participate in polydrug use. The most common reported toxicities with SCB use based on studies using Texas Poison Control records are tachycardia, agitation and irritability, drowsiness, hallucinations, delusions, hypertension, nausea, confusion, dizziness, vertigo and chest pain. Acute kidney injury has also been strongly associated with SCB use. Treatment mostly involves symptom management and supportive care. More research is needed to identify which contaminants are typically found in synthetic marijuana and to understand the interactions between different SBCs to better predict adverse health outcomes.

  7. Basolateral amygdala CB1 cannabinoid receptors mediate nicotine-induced place preference.

    Science.gov (United States)

    Hashemizadeh, Shiva; Sardari, Maryam; Rezayof, Ameneh

    2014-06-01

    In the present study, the effects of bilateral microinjections of cannabinoid CB1 receptor agonist and antagonist into the basolateral amygdala (intra-BLA) on nicotine-induced place preference were examined in rats. A conditioned place preference (CPP) apparatus was used for the assessment of rewarding effects of the drugs in adult male Wistar rats. Subcutaneous (s.c.) administration of nicotine (0.2mg/kg) induced a significant CPP, without any effect on the locomotor activity during the testing phase. Intra-BLA microinjection of a non-selective cannabinoid CB1/CB2 receptor agonist, WIN 55,212-2 (0.1-0.5 μg/rat) with an ineffective dose of nicotine (0.1mg/kg, s.c.) induced a significant place preference. On the other hand, intra-BLA administration of AM251 (20-60 ng/rat), a selective cannabinoid CB1 receptor antagonist inhibited the acquisition of nicotine-induced place preference. It should be considered that the microinjection of the same doses of WIN 55,212-2 or AM251 into the BLA, by itself had no effect on the CPP score. The administration of a higher dose of AM251 (60 ng/rat) during the acquisition decreased the locomotor activity of animals on the testing phase. Interestingly, the microinjection of AM251 (20 and 40 ng/rat), but not WIN55,212-2 (0.1-0.5 μg/rat), into the BLA inhibited the expression of nicotine-induced place preference without any effect on the locomotor activity. Taken together, these findings support the possible role of endogenous cannabinoid system of the BLA in the acquisition and the expression of nicotine-induced place preference. Furthermore, it seems that there is a functional interaction between the BLA cannabinoid receptors and nicotine in producing the rewarding effects.

  8. Pharmacology of cannabinoids.

    Science.gov (United States)

    Grotenhermen, Franjo

    2004-01-01

    Dronabinol (Delta 9-tetrahydocannabinol, THC), the main source of the pharmacological effects caused by the use of cannabis, is an agonist to both the CB1 and the CB2 subtype of cannabinoid receptors. It is available on prescription in several countries. The non-psychotropic cannabidiol (CBD), some analogues of natural cannabinoids and their metabolites, antagonists at the cannabinoid receptors and modulators of the endogenous cannabinoid system are also promising candidates for clinical research and therapeutic uses. Cannabinoid receptors are distributed in the central nervous system and many peripheral tissues including spleen, leukocytes; reproductive, urinary and gastrointestinal tracts; endocrine glands, arteries and heart. Five endogenous cannabinoids have been detected so far, of whom anandamide and 2-arachidonylglycerol are best characterized. There is evidence that besides the two cannabinoid receptor subtypes cloned so far additional cannabinoid receptor subtypes and vanilloid receptors are involved in the complex physiological functions of the cannabinoid system that include motor coordination, memory procession, control of appetite, pain modulation and neuroprotection. Strategies to modulate their activity include inhibition of re-uptake into cells and inhibition of their degradation to increase concentration and duration of action. Properties of cannabinoids that might be of therapeutic use include analgesia, muscle relaxation, immunosuppression, anti-inflammation, anti-allergic effects, sedation, improvement of mood, stimulation of appetite, anti-emesis, lowering of intraocular pressure, bronchodilation, neuroprotection and antineoplastic effects. PMID:15159677

  9. Impaired Excitatory Neurotransmission in the Urinary Bladder from the Obese Zucker Rat: Role of Cannabinoid Receptors

    Science.gov (United States)

    Blaha, Igor; Recio, Paz; Martínez, María Pilar; López-Oliva, María Elvira; Ribeiro, Ana S. F.; Agis-Torres, Ángel; Martínez, Ana Cristina; Benedito, Sara; García-Sacristán, Albino; Fernandes, Vítor S.; Hernández, Medardo

    2016-01-01

    Metabolic syndrome (MS) is a known risk factor for lower urinary tract symptoms. This study investigates whether functional and expression changes of cannabinoid CB1 and CB2 receptors are involved in the bladder dysfunction in an obese rat model with insulin resistance. Bladder samples from obese Zucker rat (OZR) and their respective controls lean Zucker rat (LZR) were processed for immunohistochemistry and western blot for studying the cannabinoid receptors expression. Detrusor smooth muscle (DSM) strips from LZR and OZR were also mounted in myographs for isometric force recordings. Neuronal and smooth muscle CB1 and CB2 receptor expression and the nerve fiber density was diminished in the OZR bladder. Electrical field stimulation (EFS) and acetylcholine (ACh) induced frequency- and concentration-dependent contractions of LZR and OZR DSM. ACh contractile responses were similar in LZR and OZR. EFS-elicited contractions, however, were reduced in OZR bladder. Cannabinoid receptor agonists and antagonists failed to modify the DSM basal tension in LZR and OZR In LZR bladder, EFS responses were inhibited by ACEA and SER-601, CB1 and CB2 receptor agonists, respectively, these effects being reversed by ACEA plus the CB1 antagonist, AM-251 or SER-601 plus the CB2 antagonist, AM-630. In OZR bladder, the inhibitory action of ACEA on nerve-evoked contractions was diminished, whereas that SER-601 did not change EFS responses. These results suggest that a diminished function and expression of neuronal cannabinoid CB1 and CB2 receptors, as well as a lower nerve fiber density is involved in the impaired excitatory neurotransmission of the urinary bladder from the OZR. PMID:27285468

  10. Early maternal deprivation and neonatal single administration with a cannabinoid agonist induce long-term sex-dependent psychoimmunoendocrine effects in adolescent rats.

    Science.gov (United States)

    Llorente, Ricardo; Arranz, Lorena; Marco, Eva-María; Moreno, Enrique; Puerto, Marta; Guaza, Carmen; De la Fuente, Mónica; Viveros, Maria-Paz

    2007-07-01

    Maternal deprivation [24h on postnatal day 9] might represent an animal model of schizophrenia and behavioural and neurochemical alterations observed in adulthood may be mediated by hippocampal impairments induced by abnormally increased glucocorticoids due to neonatal stress. We aimed to provide new data for psychoimmunoendocrine characterization of this animal model by evaluating its effects in adolescent rats of both genders. In previous studies we found that cannabinoid compounds counteracted the enhanced impulsivity of maternally deprived animals and that the cannabinoid receptor agonist WIN 55,212-2 showed neuroprotective properties in neonatal rats. So, we hypothesised that this compound could counteract at least some of the detrimental effects that we expected to find in maternally deprived animals. Accordingly, the drug was administered immediately after the maternal deprivation period. Maternally deprived males showed significantly decreased motor activity in the holeboard and the plus-maze. The cannabinoid agonist induced, exclusively in males, a significant anxiogenic-like effect, which was reversed by maternal deprivation. In the forced swimming test, both treatments independently induced depressive-like responses. Maternal deprivation reduced immunological function whereas the drug exerted tissue-dependent effects on the immune parameters analysed. Maternally deprived females showed reduced corticosterone levels whereas the cannabinoid agonist increased hormone concentration in all groups. In general, the results show detrimental effects of both treatments as well as intriguing interactions, notably in relation to emotional behaviour and certain immunological responses.

  11. Estradiol decreases cortical reactive astrogliosis after brain injury by a mechanism involving cannabinoid receptors.

    Science.gov (United States)

    López Rodríguez, Ana Belén; Mateos Vicente, Beatriz; Romero-Zerbo, Silvana Y; Rodriguez-Rodriguez, Noé; Bellini, María José; Rodriguez de Fonseca, Fernando; Bermudez-Silva, Francisco Javier; Azcoitia, Iñigo; Garcia-Segura, Luis M; Viveros, María-Paz

    2011-09-01

    The neuroactive steroid estradiol reduces reactive astroglia after brain injury by mechanisms similar to those involved in the regulation of reactive gliosis by endocannabinoids. In this study, we have explored whether cannabinoid receptors are involved in the effects of estradiol on reactive astroglia. To test this hypothesis, the effects of estradiol, the cannabinoid CB1 antagonist/inverse agonist AM251, and the cannabinoid CB2 antagonist/inverse agonist AM630 were assessed in the cerebral cortex of male rats after a stab wound brain injury. Estradiol reduced the number of vimentin immunoreactive astrocytes and the number of glial fibrillary acidic protein immunoreactive astrocytes in the proximity of the wound. The effect of estradiol was significantly inhibited by the administration of either CB1 or CB2 receptor antagonists. The effect of estradiol may be in part mediated by alterations in endocannabinoid signaling because the hormone increased in the injured cerebral cortex the messenger RNA levels of CB2 receptors and of some of the enzymes involved in the synthesis and metabolism of endocannabinoids. These findings suggest that estradiol may decrease reactive astroglia in the injured brain by regulating the activity of the endocannabinoid system.

  12. Self-medication of a cannabinoid CB2 agonist in an animal model of neuropathic pain

    OpenAIRE

    Gutierrez, Tannia; Crystal, Jonathon D.; Zvonok, Alexander M.; Makriyannis, Alexandros; Hohmann, Andrea G.

    2011-01-01

    Drug self-administration methods were used to test the hypothesis that rats would self-medicate with a cannabinoid CB2 agonist to attenuate a neuropathic pain state. Self-medication of the CB2 agonist (R,S)-AM1241, but not vehicle, attenuated mechanical hypersensitivity produced by spared nerve injury. Switching rats from (R,S)-AM1241 to vehicle self-administration also decreased lever responding in an extinction paradigm. (R,S)-AM1241 self-administration did not alter paw withdrawal threshol...

  13. Modulation of Network Oscillatory Activity and GABAergic Synaptic Transmission by CB1 Cannabinoid Receptors in the Rat Medial Entorhinal Cortex

    Directory of Open Access Journals (Sweden)

    Nicola H. Morgan

    2008-01-01

    Full Text Available Cannabinoids modulate inhibitory GABAergic neurotransmission in many brain regions. Within the temporal lobe, cannabinoid receptors are highly expressed, and are located presynaptically at inhibitory terminals. Here, we have explored the role of type-1 cannabinoid receptors (CB1Rs at the level of inhibitory synaptic currents and field-recorded network oscillations. We report that arachidonylcyclopropylamide (ACPA; 10 M, an agonist at CB1R, inhibits GABAergic synaptic transmission onto both superficial and deep medial entorhinal (mEC neurones, but this has little effect on network oscillations in beta/gamma frequency bands. By contrast, the CB1R antagonist/inverse agonist LY320135 (500 nM, increased GABAergic synaptic activity and beta/gamma oscillatory activity in superficial mEC, was suppressed, whilst that in deep mEC was enhanced. These data indicate that cannabinoid-mediated effects on inhibitory synaptic activity may be constitutively active in vitro, and that modulation of CB1R activation using inverse agonists unmasks complex effects of CBR function on network activity.

  14. Control of Inhibition by the Direct Action of Cannabinoids on GABAA Receptors

    NARCIS (Netherlands)

    Golovko, Tatiana; Min, R.; Lozovaya, Natalia; Falconer, Caroline; Yatsenko, Natalia; Tsintsadze, Timur; Tsintsadze, Vera; Ledent, Catherine; Harvey, Robert J; Belelli, Delia; Lambert, Jeremy J; Rozov, Andrei; Burnashev, Nail

    2015-01-01

    Cannabinoids are known to regulate inhibitory synaptic transmission via activation of presynaptic G protein-coupled cannabinoid CB1 receptors (CB1Rs). Additionally, recent studies suggest that cannabinoids can also directly interact with recombinant GABAA receptors (GABAARs), potentiating currents a

  15. Neurophysiological evidence for the presence of cannabinoid CB1 receptors in the laterodorsal tegmental nucleus

    DEFF Research Database (Denmark)

    Soni, Neeraj; Satpathy, Shankha; Kohlmeier, Kristi Anne

    2014-01-01

    Marijuana, which acts within the endocannabinoid (eCB) system as an agonist of the cannabinoid type 1 receptor (CB1R), exhibits addictive properties and has powerful actions on the state of arousal of an organism. The laterodorsal tegmental nucleus (LDT), as a component of the reticular activating...... the firing frequency and synaptic activity of neurons in this nucleus. Therefore, endogenous eCB transmission could play a role in processes involving the LDT, such as cortical activation and motivated behaviours and, further, behavioural actions of marijuana are probably mediated, in part, via cellular...

  16. Signaling Mechanism of Cannabinoid Receptor-2 Activation-Induced β-Endorphin Release.

    Science.gov (United States)

    Gao, Fang; Zhang, Ling-Hong; Su, Tang-Feng; Li, Lin; Zhou, Rui; Peng, Miao; Wu, Cai-Hua; Yuan, Xiao-Cui; Sun, Ning; Meng, Xian-Fang; Tian, Bo; Shi, Jing; Pan, Hui-Lin; Li, Man

    2016-08-01

    Activation of cannabinoid receptor-2 (CB2) results in β-endorphin release from keratinocytes, which then acts on primary afferent neurons to inhibit nociception. However, the underlying mechanism is still unknown. The CB2 receptor is generally thought to couple to Gi/o to inhibit cAMP production, which cannot explain the peripheral stimulatory effects of CB2 receptor activation. In this study, we found that in a keratinocyte cell line, the Gβγ subunits from Gi/o, but not Gαs, were involved in CB2 receptor activation-induced β-endorphin release. Inhibition of MAPK kinase, but not PLC, abolished CB2 receptor activation-induced β-endorphin release. Also, CB2 receptor activation significantly increased intracellular Ca(2+). Treatment with BAPTA-AM or thapsigargin blocked CB2 receptor activation-induced β-endorphin release. Using a rat model of inflammatory pain, we showed that the MAPK kinase inhibitor PD98059 abolished the peripheral effect of the CB2 receptor agonist on nociception. We thus present a novel mechanism of CB2 receptor activation-induced β-endorphin release through Gi/o-Gβγ-MAPK-Ca(2+) signaling pathway. Our data also suggest that stimulation of MAPK contributes to the peripheral analgesic effect of CB2 receptor agonists. PMID:26108183

  17. Functional Selectivity of CB2 Cannabinoid Receptor Ligands at a Canonical and Noncanonical Pathway.

    Science.gov (United States)

    Dhopeshwarkar, Amey; Mackie, Ken

    2016-08-01

    The CB2 cannabinoid receptor (CB2) remains a tantalizing, but unrealized therapeutic target. CB2 receptor ligands belong to varied structural classes and display extreme functional selectivity. Here, we have screened diverse CB2 receptor ligands at canonical (inhibition of adenylyl cyclase) and noncanonical (arrestin recruitment) pathways. The nonclassic cannabinoid (-)-cis-3-[2-hydroxy-4-(1,1-dimethylheptyl)phenyl]-trans-4-(3-hydroxypropyl)cyclohexanol (CP55940) was the most potent agonist for both pathways, while the classic cannabinoid ligand (6aR,10aR)-3-(1,1-Dimethylbutyl)-6a,7,10,10a-tetrahydro-6,6,9-trimethyl-6H-dibenzo[b,d]pyran JWH133) was the most efficacious agonist among all the ligands profiled in cyclase assays. In the cyclase assay, other classic cannabinoids showed little [(-)-trans-Δ(9)-tetrahydrocannabinol and (-)-(6aR,7,10,10aR)-tetrahydro-6,6,9-trimethyl-3-(1-methyl-1-phenylethyl)-6H-dibenzo[b,d]pyran-1-ol] (KM233) to no efficacy [(6aR,10aR)-1-methoxy-6,6,9-trimethyl-3-(2-methyloctan-2-yl)-6a,7,10,10a-tetrahydrobenzo[c]chromene(L759633) and (6aR,10aR)-3-(1,1-dimethylheptyl)-6a,7,8,9,10,10a-hexahydro-1-methoxy-6,6-dimethyl-9-methylene-6H-dibenzo[b,d]pyran]L759656. Most aminoalkylindoles, including [(3R)-​2,​3-​dihydro-​5-​methyl-​3-​(4-​morpholinylmethyl)pyrrolo[1,​2,​3-​de]-​1,​4-​benzoxazin-​6-​yl]-​1-​naphthalenyl-​methanone,​ monomethanesulfonate (WIN55212-2), were moderate efficacy agonists. The cannabilactone 3-(1,1-dimethyl-heptyl)-1-hydroxy-9-methoxy-benzo(c)chromen-6-one (AM1710) was equiefficacious to CP55940 to inhibit adenylyl cyclase, albeit with lower potency. In the arrestin recruitment assays, all classic cannabinoid ligands failed to recruit arrestins, indicating a bias toward G-protein coupling for this class of compound. All aminoalkylindoles tested, except for WIN55212-2 and (1-​pentyl-​1H-​indol-​3-​yl)(2,​2,​3,​3-​tetramethylcyclopropyl)-​methanone (UR144), failed

  18. Biphasic Effects of Cannabinoids in Anxiety Responses: CB1 and GABAB Receptors in the Balance of GABAergic and Glutamatergic Neurotransmission

    Science.gov (United States)

    Rey, Alejandro Aparisi; Purrio, Martin; Viveros, Maria-Paz; Lutz, Beat

    2012-01-01

    Biphasic effects of cannabinoids have been shown in processes such as feeding behavior, motor activity, motivational processes and anxiety responses. Using two different tests for the characterization of anxiety-related behavior (elevated plus-maze and holeboard), we first identified in wild-type C57BL/6N mice, two doses of the synthetic CB1 cannabinoid receptor agonist CP-55,940 with anxiolytic (1 μg/kg) and anxiogenic properties (50 μg/kg), respectively. To clarify the role of CB1 receptors in this biphasic effect, both doses were applied to two different conditional CB1 receptor knockout (KO) mouse lines, GABA-CB1-KO (CB1 receptor inactivation in forebrain GABAergic neurons) and Glu-CB1-KO (CB1 receptor inactivation in cortical glutamatergic neurons). We found that the anxiolytic-like effects of the low dose of cannabinoids are mediated via the CB1 receptor on cortical glutamatergic terminals, because this anxiolytic-like response was abrogated only in Glu-CB1-KO mice. On the contrary, the CB1 receptor on the GABAergic terminals is required to induce an anxiogenic-like effect under a high-dose treatment because of the fact that this effect was abolished specifically in GABA-CB1-KO mice. These experiments were carried out in both sexes, and no differences occurred with the doses tested in the mutant mice. Interestingly, the positive allosteric modulation of GABAB receptor with GS-39783 was found to largely abrogate the anxiogenic-like effect of the high dose of CP-55,940. Our results shed new light in further understanding the biphasic effects of cannabinoids at the molecular level and, importantly, pave the way for the development of novel anxiolytic cannabinoid drugs, which may have favorable effect profiles targeting the CB1 receptor on glutamatergic terminals. PMID:22850737

  19. Targeting Cannabinoid CB2 Receptors in the Central Nervous System. Medicinal Chemistry Approaches with Focus on Neurodegenerative Disorders

    Science.gov (United States)

    Navarro, Gemma; Morales, Paula; Rodríguez-Cueto, Carmen; Fernández-Ruiz, Javier; Jagerovic, Nadine; Franco, Rafael

    2016-01-01

    Endocannabinoids activate two types of specific G-protein-coupled receptors (GPCRs), namely cannabinoid CB1 and CB2. Contrary to the psychotropic actions of agonists of CB1 receptors, and serious side effects of the selective antagonists of this receptor, drugs acting on CB2 receptors appear as promising drugs to combat CNS diseases (Parkinson's disease, Huntington's chorea, cerebellar ataxia, amyotrohic lateral sclerosis). Differential localization of CB2 receptors in neural cell types and upregulation in neuroinflammation are keys to understand the therapeutic potential in inter alia diseases that imply progressive neurodegeneration. Medicinal chemistry approaches are now engaged to develop imaging tools to map receptors in the living human brain, to develop more efficacious agonists, and to investigate the possibility to develop allosteric modulators. PMID:27679556

  20. Self-medication of a cannabinoid CB2 agonist in an animal model of neuropathic pain.

    Science.gov (United States)

    Gutierrez, Tannia; Crystal, Jonathon D; Zvonok, Alexander M; Makriyannis, Alexandros; Hohmann, Andrea G

    2011-09-01

    Drug self-administration methods were used to test the hypothesis that rats would self-medicate with a cannabinoid CB(2) agonist to attenuate a neuropathic pain state. Self-medication of the CB(2) agonist (R,S)-AM1241, but not vehicle, attenuated mechanical hypersensitivity produced by spared nerve injury. Switching rats from (R,S)-AM1241 to vehicle self-administration also decreased lever responding in an extinction paradigm. (R,S)-AM1241 self-administration did not alter paw withdrawal thresholds in sham-operated or naive animals. The percentage of active lever responding was similar in naive groups self-administering vehicle or (R,S)-AM1241. The CB(2) antagonist SR144528 blocked both antiallodynic effects of (R,S)-AM1241 self-medication and the percentage of active lever responding in neuropathic (but not naive) rats. Neuropathic and sham groups exhibited similar percentages of active lever responding for (R,S)-AM1241 on a fixed ratio 1 (FR1) schedule. However, neuropathic animals worked harder than shams to obtain (R,S)-AM1241 when the schedule of reinforcement was increased (to FR6). (R,S)-AM1241 self-medication on FR1, FR3, or FR6 schedules attenuated nerve injury-induced mechanical allodynia. (R,S)-AM1241 (900μg intravenously) failed to produce motor ataxia observed after administration of the mixed CB(1)/CB(2) agonist WIN55,212-2 (0.5mg/kg intravenously). Our results suggest that cannabinoid CB(2) agonists may be exploited to treat neuropathic pain with limited drug abuse liability and central nervous system side effects. These studies validate the use of drug self-administration methods for identifying nonpsychotropic analgesics possessing limited abuse potential. These methods offer potential to elucidate novel analgesics that suppress spontaneous neuropathic pain that is not measured by traditional assessments of evoked pain. PMID:21550725

  1. Converging action of alcohol consumption and cannabinoid receptor activation on adult hippocampal neurogenesis.

    Science.gov (United States)

    Alén, Francisco; Mouret, Aurélie; Viveros, Maria-Paz; Llorente, Ricardo; Lepousez, Gabriel; Lledo, Pierre-Marie; López-Moreno, José Antonio

    2010-03-01

    Alcoholism is characterized by successive periods of abstinence and relapse, resulting from long-lasting changes in various circuits of the central nervous system. Accumulating evidence points to the endocannabinoid system as one of the most relevant biochemical systems mediating alcohol addiction. The endocannabinoid system regulates adult neurogenesis, a form of long-lasting adult plasticity that occurs in a few areas of the brain, including the dentate gyrus. Because exposure to psychotropic drugs regulates adult neurogenesis, it is possible that neurogenesis might be implicated in the pathophysiology, and hence treatment, of neurobiological illnesses related to drugs of abuse. Here, we investigated the sensitivity of adult hippocampal neurogenesis to alcohol and the cannabinoid receptor agonist WIN 55,212-2 (WIN). Specifically, we analysed the potential link between alcohol relapse, cannabinoid receptor activation, and adult neurogenesis. Adult rats were exposed to subchronic alcohol binge intoxication and received the cannabinoid receptor agonist WIN. Another group of rats were subjected to an alcohol operant self-administration task. Half of these latter animals had continuous access to alcohol, while the other half were subjected to alcohol deprivation, with or without WIN administration. WIN treatment, when administered during alcohol deprivation, resulted in the greatest increase in alcohol consumption during relapse. Together, forced alcohol binge intoxication and WIN administration dramatically reduced hippocampal neurogenesis. Furthermore, adult neurogenesis inversely correlated with voluntary consumption of alcohol. These findings suggest that adult hippocampal neurogenesis is a key factor involved in drug abuse and that it may provide a new strategy for the treatment of alcohol addiction and dependence.

  2. Frequency-Dependent Cannabinoid Receptor-Independent Modulation of Glycine Receptors by Endocannabinoid 2-AG

    OpenAIRE

    Natalia eLozovaya; Marat eMukhtarov; Timur eTsintsadze; Catherine eLedent; Nail eBurnashev; Piotr eBregestovski

    2011-01-01

    Endocannabinoids are known as retrograde messengers, being released from the postsynaptic neuron and acting on specific presynaptic G-protein-coupled cannabinoid (CB) receptors to decrease neurotransmitter release. Also, at physiologically relevant concentrations cannabinoids can directly modulate the function of voltage-gated and receptor-operated ion channels. Using patch-clamp recording we analyzed the consequences of the direct action of an endocannabinoid, 2-arachidonoylglycerol (2-AG), ...

  3. Cannabinoid receptor 1 signaling in cardiovascular regulating nuclei in the brainstem: A review

    OpenAIRE

    Badr M. Ibrahim; Abdel-Rahman, Abdel A.

    2013-01-01

    Cannabinoids elicit complex hemodynamic responses in experimental animals that involve both peripheral and central sites. Centrally administered cannabinoids have been shown to predominantly cause pressor response. However, very little is known about the mechanism of the cannabinoid receptor 1 (CB1R)-centrally evoked pressor response. In this review, we provided an overview of the contemporary knowledge regarding the cannabinoids centrally elicited cardiovascular responses and the possible un...

  4. Vascular Dysfunction in a Transgenic Model of Alzheimer's Disease: Effects of CB1R and CB2R Cannabinoid Agonists

    Science.gov (United States)

    Navarro-Dorado, Jorge; Villalba, Nuria; Prieto, Dolores; Brera, Begoña; Martín-Moreno, Ana M.; Tejerina, Teresa; de Ceballos, María L.

    2016-01-01

    There is evidence of altered vascular function, including cerebrovascular, in Alzheimer's disease (AD) and transgenic models of the disease. Indeed vasoconstrictor responses are increased, while vasodilation is reduced in both conditions. β-Amyloid (Aβ) appears to be responsible, at least in part, of alterations in vascular function. Cannabinoids, neuroprotective and anti-inflammatory agents, induce vasodilation both in vivo and in vitro. We have demonstrated a beneficial effect of cannabinoids in models of AD by preventing glial activation. In this work we have studied the effects of these compounds on vessel density in amyloid precursor protein (APP) transgenic mice, line 2576, and on altered vascular responses in aortae isolated ring. First we showed increased collagen IV positive vessels in AD brain compared to control subjects, with a similar increase in TgAPP mice, which was normalized by prolonged oral treatment with the CB1/CB2 mixed agonist WIN 55,212-2 (WIN) and the CB2 selective agonist JWH-133 (JWH). In Tg APP mice the vasoconstriction induced by phenylephrine and the thromboxane agonist U46619 was significantly increased, and no change in the vasodilation to acetylcholine (ACh) was observed. Tg APP displayed decreased vasodilation to both cannabinoid agonists, which were able to prevent decreased ACh relaxation in the presence of Aβ. In summary, we have confirmed and extended the existence of altered vascular responses in Tg APP mice. Moreover, our results suggest that treatment with cannabinoids may ameliorate the vascular responses in AD-type pathology. PMID:27695396

  5. 大麻素受体激动剂WIN55,212-2预处理对大鼠脊髓缺血再灌注损伤的保护作用研究%Protective effects of cannabinoid receptor agonist WIN55,212-2 preconditioning on spinal cord ischemia reperfusion injury in rats

    Institute of Scientific and Technical Information of China (English)

    荆娜; 马虹

    2015-01-01

    目的 探讨大麻素受体激动剂WIN55,212-2预处理对大鼠脊髓缺血再灌注损伤的保护作用.方法 32只SD大鼠按随机数字表法分为4组(n=8),分别为Sham组(假手术组)、Control组(单纯缺血对照组)、二甲基亚砜(DMSO)组(溶剂组)、WIN组(WIN55,212-2预处理组).Control组在诱导脊髓缺血前30 min腹腔内注射生理盐水0.3ml,DMSO组在诱导脊髓缺血前30 min腹腔内注射DMSO 0.3 ml,WIN组在诱导脊髓缺血前30 min腹腔内注射WIN55,212-2 1 mg/kg.分别于再灌注24、48 h采用Tarlov评分标准对后肢运动功能进行评价,之后取L4~L6脊髓组织行病理学检查.结果 再灌注24h和48 h,缺血组Tarlov评分均低于Sham组(P<0.05),WIN组Tarlov评分明显高于Control组和DMSO组(P<0.05).缺血组前角正常神经元数量少于Sham组(P<0.05),WIN组明显多于Control组和DMSO组(P<0.05).结论 大麻素受体激动剂WIN55,212-2预处理能够减轻大鼠脊髓缺血再灌注损伤.%Objective To explore the effects of cannabinoid receptor agonist WIN55,212-2 preconditioning on spinal cord ischemia reperfusion injury in rats.Methods A total of 32 male Sprague-Dawley rats was randomly divided into four groups (n =8):sham group,control group,dimethyl sulfoxide(DMSO) group which was given intraperitoneally DMSO 0.3 ml 30 min before ischemia reperfusion,and WIN group which was given intraperitoneally WIN55,212-2 1 mg/kg 30 min before ischemia reperfusion.Each rat was neurologically assessed at 24 h and 48 h after reperfusion by Tarlov scale,and the number of normal motor neurons at anterior horn of the spinal cord was recorded.Res uits The Tarlov scale of WIN group was significantly higher than that control and DMSO groups (P < 0.05).There were more normal motor neurons at anterior horn of the spinal cord in WIN group than those in control and DMSO groups (P < 0.05).Conclusions Cannabinoid receptor agonist WIN55,212-2 preconditioning might attenuate spinal cord ischemia

  6. Phase I hydroxylated metabolites of the K2 synthetic cannabinoid JWH-018 retain in vitro and in vivo cannabinoid 1 receptor affinity and activity.

    Directory of Open Access Journals (Sweden)

    Lisa K Brents

    Full Text Available BACKGROUND: K2 products are synthetic cannabinoid-laced, marijuana-like drugs of abuse, use of which is often associated with clinical symptoms atypical of marijuana use, including hypertension, agitation, hallucinations, psychosis, seizures and panic attacks. JWH-018, a prevalent K2 synthetic cannabinoid, is structurally distinct from Δ(9-THC, the main psychoactive ingredient in marijuana. Since even subtle structural differences can lead to differential metabolism, formation of novel, biologically active metabolites may be responsible for the distinct effects associated with K2 use. The present study proposes that K2's high adverse effect occurrence is due, at least in part, to distinct JWH-018 metabolite activity at the cannabinoid 1 receptor (CB1R. METHODS/PRINCIPAL FINDINGS: JWH-018, five potential monohydroxylated metabolites (M1-M5, and one carboxy metabolite (M6 were examined in mouse brain homogenates containing CB1Rs, first for CB1R affinity using a competition binding assay employing the cannabinoid receptor radioligand [(3H]CP-55,940, and then for CB1R intrinsic efficacy using an [(35S]GTPγS binding assay. JWH-018 and M1-M5 bound CB1Rs with high affinity, exhibiting K(i values that were lower than or equivalent to Δ(9-THC. These molecules also stimulated G-proteins with equal or greater efficacy relative to Δ(9-THC, a CB1R partial agonist. Most importantly, JWH-018, M2, M3, and M5 produced full CB1R agonist levels of activation. CB1R-mediated activation was demonstrated by blockade with O-2050, a CB1R-selective neutral antagonist. Similar to Δ(9-THC, JWH-018 and M1 produced a marked depression of locomotor activity and core body temperature in mice that were both blocked by the CB1R-preferring antagonist/inverse agonist AM251. CONCLUSIONS/SIGNIFICANCE: Unlike metabolites of most drugs, the studied JWH-018 monohydroxylated compounds, but not the carboxy metabolite, retain in vitro and in vivo activity at CB1Rs. These observations

  7. Expresión de receptores cannabinoides en el desarrollo embrionario del pez cebra

    OpenAIRE

    Florido García, Virginia

    2009-01-01

    [ES]Este trabajo trata sobre la expresión de receptores cannabinoides en el desarrollo embrionario del pez cebra [EN]This paper deals with the expression of cannabinoid receptors in the embryonic development of zebrafish Trabajo de Fin de Máster del Máster en Neurociencias, curso 2008-2009.

  8. GPR55 regulates cannabinoid 2 receptor-mediated responses in human neutrophils

    Institute of Scientific and Technical Information of China (English)

    Nariman A B Balenga; Maria Waldhoer; Elma Aflaki; Julia Kargl; Wolfgang Platzer; Ralf Schr(o)der; Stefanie Bl(a)ttermann; Evi Kostenis; Andrew J Brown; Akos Heinemann

    2011-01-01

    The directional migration of neutrophils towards inflammatory mediators,such as chemokines and cannabinoids,occurs via the activation of seven transmembrane G protein coupled receptors (7TM/GPCRs) and is a highly organized process.A crucial role for controlling neutrophil migration has been ascribed to the cannabinoid CB2 receptor (CB2R),but additional modulatory sites distinct from CB2R have recently been suggested to impact CB2R-mediated effector functions in neutrophils.Here,we provide evidence that the recently de-orphanized 7TM/GPCR GPR55potently modulates CB2R-mediated responses.We show that GPR55 is expressed in human blood neutrophils and its activation augments the migratory response towards the CB2R agonist 2-arachidonoylglycerol (2-AG),while inhibiting neutrophil degranulation and reactive oxygen species (ROS) production.Using HEK293 and HL60 cell lines,along with primary neutrophils,we show that GPR55 and CB2R interfere with each other's signaling pathways at the level of small GTPases,such as Rac2 and Cdc42.This ultimately leads to cellular polarization and efficient migration as well as abrogation of degranulation and ROS formation in neutrophils.Therefore,GPR55 limits the tissueinjuring inflammatory responses mediated by CB2R,while it synergizes with CB2R in recruiting neutrophils to sites of inflammation.

  9. Bi-directional CB1 receptor-mediated cardiovascular effects of cannabinoids in anaesthetized rats: role of the paraventricular nucleus.

    Science.gov (United States)

    Grzeda, E; Schlicker, E; Luczaj, W; Harasim, E; Baranowska-Kuczko, M; Malinowska, B

    2015-06-01

    The activation of cannabinoid CB1 receptors decreases and increases blood pressure (BP) in anaesthetized and conscious rats, respectively. The aim of our study was to check the possible involvement of CB1 receptors in the paraventricular nucleus of the hypothalamus (PVN) in the cardiovascular effects of cannabinoids in rats. Methanandamide (metabolically stable analogue of the endocannabinoid anandamide) and the synthetic cannabinoid receptor agonist CP55940 were microinjected into the PVN of urethane-anaesthetized rats twice (S1 and S2, 20 min apart). Receptor antagonists were administered intravenously (i.v.) 5 min before S1. Methanandamide and CP55940 decreased blood pressure by 15 - 20%. The CB1 receptor antagonist AM251 reversed the depressor effect into a pressor response of 20 - 30%. The pressor effect of CP55940 observed in the presence of AM251 i.v. was reduced by AM251 given additionally into the PVN but not by the i.v. injection of the CB2 antagonist SR144528 or the vanilloid TRPV1 antagonist ruthenium red. In the presence of the peripherally restricted CB1 receptor antagonist AM6545, CP55940 given into the PVN increased BP by 40%. AM6545 reversed the decrease in BP induced by CP55940 i.v. into a marked increase. Bilateral chemical lesion of the PVN by kainic acid abolished all cardiovascular effects of CP55940 i.v. In conclusion, the cannabinoid CP55940 administered to the PVN of urethane-anaesthetized rats can induce depressor and pressor effects. The direction of the response probably depends on the sympathetic tone. The centrally induced hypertensive response of CP55940 can, in addition, be masked by peripheral CB1 receptors.

  10. Cannabinoids and their medicinal potential

    Directory of Open Access Journals (Sweden)

    Deepika Tikoo

    2012-04-01

    Full Text Available Cannabis sativa L preparations have been used therapeutically since many years. Inspite of their medicinal value, the danger of its abusive potential led to the ban on its use in clinical practice in many countries. The recent research and in depth knowledge about the cannabinoid system which throw a light on their disease management potential has paved way for the cannabinoids to become a new therapeutic focus of attention. Cannabinoids are a group of compounds that mediate their effects through cannabinoid receptors which include CB1, predominantly expressed in the brain and CB2 which is primarily found in the cells of the immune system. Despite the addictive properties of cannabis, the therapeutic value of cannabinoids is too high to be put aside. Numerous diseases such as anorexia, pain, inflammation, obesity, cardiovascular disorders, neurodegenerative diseases, cancer, gastrointestinal diseases, hepatic disorders, skin related diseases, respiratory disorders like asthma and eye diseases like glaucoma have suggested cannabinoid agonists/ antagonists/ cannabinoids related compounds as potential treatment options. Developments of new specific ligands for the cannabinoid receptors are now underway and it needs to be seen, if in future, they can prove to be a boon for the medical world. The paper reviews the current understanding of the cannabinoid receptors, their ligands and their possible role in various diseases supported by preclinical and clinical studies. [Int J Basic Clin Pharmacol 2012; 1(2.000: 48-59

  11. Cannabinoid agonists rearrange synaptic vesicles at excitatory synapses and depress motoneuron activity in vivo.

    Science.gov (United States)

    García-Morales, Victoria; Montero, Fernando; Moreno-López, Bernardo

    2015-05-01

    Impairment of motor skills is one of the most common acute adverse effects of cannabis. Related studies have focused mainly on psychomotor alterations, and little is known about the direct impact of cannabinoids (CBs) on motoneuron physiology. As key modulators of synaptic function, CBs regulate multiple neuronal functions and behaviors. Presynaptic CB1 mediates synaptic strength depression by inhibiting neurotransmitter release, via a poorly understood mechanism. The present study examined the effect of CB agonists on excitatory synaptic inputs incoming to hypoglossal motoneurons (HMNs) in vitro and in vivo. The endocannabinoid anandamide (AEA) and the synthetic CB agonist WIN 55,212-2 rapidly and reversibly induced short-term depression (STD) of glutamatergic synapses on motoneurons by a presynaptic mechanism. Presynaptic effects were fully reversed by the CB1-selective antagonist AM281. Electrophysiological and electron microscopy analysis showed that WIN 55,212-2 reduced the number of synaptic vesicles (SVs) docked to active zones in excitatory boutons. Given that AM281 fully abolished depolarization-induced depression of excitation, motoneurons can be feasible sources of CBs, which in turn act as retrograde messengers regulating synaptic function. Finally, microiontophoretic application of the CB agonist O-2545 reversibly depressed, presumably via CB1, glutamatergic inspiratory-related activity of HMNs in vivo. Therefore, evidence support that CBs, via presynaptic CB1, induce excitatory STD by reducing the readily releasable pool of SVs at excitatory synapses, then attenuating motoneuron activity. These outcomes contribute a possible mechanistic basis for cannabis-associated motor performance disturbances such as ataxia, dysarthria and dyscoordination. PMID:25595101

  12. Cannabinoid CB1 receptor signaling dichotomously modulates inhibitory and excitatory synaptic transmission in rat inner retina.

    Science.gov (United States)

    Wang, Xiao-Han; Wu, Yi; Yang, Xiao-Fang; Miao, Yanying; Zhang, Chuan-Qiang; Dong, Ling-Dan; Yang, Xiong-Li; Wang, Zhongfeng

    2016-01-01

    In the inner retina, ganglion cells (RGCs) integrate and process excitatory signal from bipolar cells (BCs) and inhibitory signal from amacrine cells (ACs). Using multiple labeling immunohistochemistry, we first revealed the expression of the cannabinoid CB1 receptor (CB1R) at the terminals of ACs and BCs in rat retina. By patch-clamp techniques, we then showed how the activation of this receptor dichotomously regulated miniature inhibitory postsynaptic currents (mIPSCs), mediated by GABAA receptors and glycine receptors, and miniature excitatory postsynaptic currents (mEPSCs), mediated by AMPA receptors, of RGCs in rat retinal slices. WIN55212-2 (WIN), a CB1R agonist, reduced the mIPSC frequency due to an inhibition of L-type Ca(2+) channels no matter whether AMPA receptors were blocked. In contrast, WIN reduced the mEPSC frequency by suppressing T-type Ca(2+) channels only when inhibitory inputs to RGCs were present, which could be in part due to less T-type Ca(2+) channels of cone BCs, presynaptic to RGCs, being in an inactivation state under such condition. This unique feature of CB1R-mediated retrograde regulation provides a novel mechanism for modulating excitatory synaptic transmission in the inner retina. Moreover, depolarization of RGCs suppressed mIPSCs of these cells, an effect that was eliminated by the CB1R antagonist SR141716, suggesting that endocannabinoid is indeed released from RGCs.

  13. Controlled downregulation of the cannabinoid CB1 receptor provides a promising approach for the treatment of obesity and obesity-derived type 2 diabetes.

    Science.gov (United States)

    Lu, Dai; Dopart, Rachel; Kendall, Debra A

    2016-01-01

    Increased activity of the endocannabinoid system has emerged as a pathogenic factor in visceral obesity, which is a risk factor for type 2 diabetes mellitus (T2DM). The endocannabinoid system is composed of at least two Gprotein-coupled receptors (GPCRs), the cannabinoid receptor type 1 (CB1), and the cannabinoid receptor type 2 (CB2). Downregulation of CB1 activity in rodents and humans has proven efficacious to reduce food intake, abdominal adiposity, fasting glucose levels, and cardiometabolic risk factors. Unfortunately, downregulation of CB1 activity by universally active CB1 inverse agonists has been found to elicit psychiatric side effects, which led to the termination of using globally active CB1 inverse agonists to treat diet-induced obesity. Interestingly, preclinical studies have shown that downregulation of CB1 activity by CB1 neutral antagonists or peripherally restricted CB1 inverse agonists provided similar anorectic effects and metabolic benefits without psychiatric side effects seen in globally active CB1 inverse agonists. Furthermore, downregulation of CB1 activity may ease endoplasmic reticulum and mitochondrial stress which are contributors to obesity-induced insulin resistance and type 2 diabetes. This suggests new approaches for cannabinoid-based therapy in the management of obesity and obesity-related metabolic disorders including type 2 diabetes.

  14. Cannabinoid receptor 1 signaling in embryo neurodevelopment.

    Science.gov (United States)

    Psychoyos, Delphine; Vinod, K Yaragudri; Cao, Jin; Xie, Shan; Hyson, Richard L; Wlodarczyk, Bogdan; He, Weimin; Cooper, Thomas B; Hungund, Basalingappa L; Finnell, Richard H

    2012-04-01

    In utero exposure to tetrahydrocannabinol, the psychoactive component of marijuana, is associated with an increased risk for neurodevelopmental defects in the offspring by interfering with the functioning of the endocannabinoid (eCB) system. At the present time, it is not clearly known whether the eCB system is present before neurogenesis. Using an array of biochemical techniques, we analyzed the levels of CB1 receptors, eCBs (AEA and 2-AG), and the enzymes (NAPE-PLD, DAGLα, DAGLβ, MAGL, and FAAH) involved in the metabolism of the eCBs in chick and mouse models during development. The findings demonstrate the presence of eCB system in early embryo before neurogenesis. The eCB system might play a critical role in early embryogenesis and there might be adverse developmental consequences of in utero exposure to marijuana and other drugs of abuse during this period.

  15. Activation of cannabinoid CB1 receptors in the ventral hippocampus improved stress-induced amnesia in rat.

    Science.gov (United States)

    Mohammadmirzaei, Negin; Rezayof, Ameneh; Ghasemzadeh, Zahra

    2016-09-01

    The ventral hippocampus (VH) has a high distribution of cannabinoid CB1 receptors which are important in modulating stress responses. Stress exposure activates the hypothalamic-pituitary-adrenal axis (HPA) which can impact hippocampal formation to change hippocampus-based memories. The purpose of the present study was to determine the possible role of the VH cannabinoid CB1 receptors in stress-induced amnesia using a step-through passive avoidance procedure in male Wistar rats. In order to induce acute stress, the animals were placed on an elevated platform for different time periods (10, 20 and 30min). Our results indicated that post-training 20 and 30min exposure to stress, but not 10min, induced amnesia. Post-training microinjection of a cannabinoid CB1 receptor agonist, arachydonilcyclopropylamide (ACPA; 2.5-7.5ng/rat) into the VH (intra-VH) induced amnesia. Interestingly, post-training intra-VH microinjection of the same doses of ACPA improved stress-induced amnesia. On the other hand, post-training intra-VH microinjection of a selective CB1 receptor antagonist, AM-251 (20-50ng/rat) with exposure to an ineffective stress (10min) potentiated the effect of stress on memory consolidation and induced amnesia. It should be noted that post-training intra-VH microinjection of the same doses of AM-251 alone had no effect on memory consolidation. Our results revealed that post-training intra-VH microinjection of AM-251, prior to ACPA microinjection, inhibited the reversal effect of ACPA on acute elevated platform stress. Taken together, it can be concluded that exposure to post-training inescapable stress impaired memory consolidation. The impairing effects of stress on memory retrieval may be mediated by the VH cannabinoid CB1 receptors.

  16. Constitutive cannabinoid 1 and mu opioid receptor activity in the ventral tegmental area: occurrence, function and therapeutic relevance

    OpenAIRE

    Meye, F J

    2012-01-01

    Cannabinoid 1 receptors (CB1Rs) play a crucial role in regulating systems dedicated to processing rewards and emotions. It was known that in artificial systems, CB1Rs can exhibit activity that is independent of the typical agonist-driven form. However, it remained largely unclear whether this constitutive activity also occurred in native tissue (e.g. the brain), and if so, what role it plays in neurotransmission and behavior. In this thesis we have taken a multi-disciplinary approach to show ...

  17. Cannabinoid receptor 1 signaling in cardiovascular regulating nuclei in the brainstem: A review

    Directory of Open Access Journals (Sweden)

    Badr M. Ibrahim

    2014-03-01

    Full Text Available Cannabinoids elicit complex hemodynamic responses in experimental animals that involve both peripheral and central sites. Centrally administered cannabinoids have been shown to predominantly cause pressor response. However, very little is known about the mechanism of the cannabinoid receptor 1 (CB1R-centrally evoked pressor response. In this review, we provided an overview of the contemporary knowledge regarding the cannabinoids centrally elicited cardiovascular responses and the possible underlying signaling mechanisms. The current review focuses on the rostral ventrolateral medulla (RVLM as the primary brainstem nucleus implicated in CB1R-evoked pressor response.

  18. Structure of a cannabinoid receptor and functional expression of the cloned cDNA.

    Science.gov (United States)

    Matsuda, L A; Lolait, S J; Brownstein, M J; Young, A C; Bonner, T I

    1990-08-01

    Marijuana and many of its constituent cannabinoids influence the central nervous system (CNS) in a complex and dose-dependent manner. Although CNS depression and analgesia are well documented effects of the cannabinoids, the mechanisms responsible for these and other cannabinoid-induced effects are not so far known. The hydrophobic nature of these substances has suggested that cannabinoids resemble anaesthetic agents in their action, that is, they nonspecifically disrupt cellular membranes. Recent evidence, however, has supported a mechanism involving a G protein-coupled receptor found in brain and neural cell lines, and which inhibits adenylate cyclase activity in a dose-dependent, stereoselective and pertussis toxin-sensitive manner. Also, the receptor is more responsive to psychoactive cannabinoids than to non-psychoactive cannabinoids. Here we report the cloning and expression of a complementary DNA that encodes a G protein-coupled receptor with all of these properties. Its messenger RNA is found in cell lines and regions of the brain that have cannabinoid receptors. These findings suggest that this protein is involved in cannabinoid-induced CNS effects (including alterations in mood and cognition) experienced by users of marijuana. PMID:2165569

  19. Behavioral effects of D3 receptor inhibition and 5-HT4 receptor activation on animals undergoing chronic cannabinoid exposure during adolescence.

    Science.gov (United States)

    Abboussi, Oualid; Said, Nadia; Fifel, Karim; Lakehayli, Sara; Tazi, Abdelouahhab; El Ganouni, Soumaya

    2016-04-01

    Chronic exposure to cannabinoids during adolescence results in long-lasting behavioral deficits that match some symptomatologic aspects of schizophrenia. The aim of this study was to investigate the reversibility of the emotional and the cognitive effects of chronic exposure to cannabinoids during adolescence, via subsequent modulation of the serotoninergic 5-HT4 and dopaminergic D3 receptors. RS67333 as a 5-HT4 agonist and U-99194A as a D3 antagonist were administered separately at 1 mg/kg and 20 mg/kg, and in combination at 0.5 mg/kg and 10 mg/kg to adult animals undergoing chronic treatment with the synthetic cannabinoid receptor agonist WIN55,212-2 (1 mg/kg) during adolescence. Animals were tested for anxiety-like behavior and episodic-like memory in the open field and novel object recognition tests respectively 30 minutes after the last drug administration. Chronic WIN55,212-2 treated animals exhibited a lasting disruption of episodic memory and increased anxiety levels. The effect on episodic-like memory were partially restored by acute administration of RS67333 and U-99194A and completely by administration of both drugs in combination at lower doses. However, only RS67333 (20 mg/kg) improved the anxiogenic-like effect of WIN55,212-2. These findings give further support that chronic exposure to cannabinoids during adolescence may be used as an animal model for schizophrenia, and highlight D3 and 5-HT4 receptors as potential targets for an enhanced treatment of the cognitive aspect of this disease. PMID:26497809

  20. Negative cooperativity in binding of muscarinic receptor agonists and GDP as a measure of agonist efficacy

    OpenAIRE

    Jakubík, J; Janíčková, H; El-Fakahany, EE; Doležal, V

    2011-01-01

    BACKGROUND AND PURPOSE Conventional determination of agonist efficacy at G-protein coupled receptors is measured by stimulation of guanosine-5′-γ−thiotriphosphate (GTPγS) binding. We analysed the role of guanosine diphosphate (GDP) in the process of activation of the M2 muscarinic acetylcholine receptor and provide evidence that negative cooperativity between agonist and GDP binding is an alternative measure of agonist efficacy. EXPERIMENTAL APPROACH Filtration and scintillation proximity ass...

  1. CB1大麻素受体激动剂抑制基质金属蛋白酶参与脊髓损伤后血-脊髓屏障通透性调节%Involvement of CB1 cannabinoid receptor agonist in the permeability of blood spinal cord barrier after acute spinal cord in-jury in rat model

    Institute of Scientific and Technical Information of China (English)

    董宝铁; 李泓; 费良健; 王岩峰

    2015-01-01

    目的:探讨CB1大麻素受体激动剂在大鼠脊髓损伤后对血-脊髓屏障通透性调节的作用。方法将150只雌性SD大鼠随机分为假手术组( Sham组)、脊髓损伤组( SCI组)和CB1激动剂处理组( ACEA组)。采用改良Allen法建立T9脊髓损伤实验动物模型。 Sham组仅行T9椎板切除术,SCI组和ACEA组以30 g·cm致伤力制作模型。 ACEA组建模成功后,每日腹腔给药ACEA 3mg/(kg·d);Sham组和SCI组以生理盐水代替。建模术后12、24、72 h分时段处死动物,取T8~T10脊髓节段,Evans蓝含量测定法检测SCI后血-脊髓屏障通透性变化,定量RT-PCR法检测脊髓组织基质金属蛋白酶9(MMP9)表达水平。结果 Sham组脊髓通透性无改变,脊髓组织中无Evans蓝渗入,ACEA组Evans蓝通过血-脊髓屏障渗漏至脊髓,但渗漏量明显低于SCI组。 ACEA组MMP9表达水平显著低于Sci组。结论 CB1受体激动剂ACEA能降低Allen′s大鼠脊髓损伤模型血-脊髓屏障的破坏,其作用机制可能与MMP9的表达下调相关。%Objective To investigate whether the CB1 cannabinoid receptor agonist has regulating effect on permeability of blood spi-nal cord barrier( BSCB) after spinal cord injury( SCI) in rat model. Methods Totally 150 female SD rats were randomly divided into three groups,including sham operation group(Sham group),spinal cord injury group(SCI group)and ACEA treatment group(ACEA group). Modified Allen′s method was carried out at T9 level spinal segment for SCI group and ACEA group to induce acute SCI. While Sham group only underwent laminectomy. Rats in ACEA group were treated with ACEA 3 mg/( kg·d) after surgery until killed. After modeling,the animals were sacrificed at 12,24 and 72 hours,and the level of permeability for BSC was detected by Evans blue assay at T8-T10. The expression level of MMP9 was detected by quantitative RT-PCR method. Results There was no change in the permeabil-ity of BSCB for the Sham group,no Evans blue in the

  2. Computational Prediction and Biochemical Analyses of New Inverse Agonists for the CB1 Receptor.

    Science.gov (United States)

    Scott, Caitlin E; Ahn, Kwang H; Graf, Steven T; Goddard, William A; Kendall, Debra A; Abrol, Ravinder

    2016-01-25

    Human cannabinoid type 1 (CB1) G-protein coupled receptor is a potential therapeutic target for obesity. The previously predicted and experimentally validated ensemble of ligand-free conformations of CB1 [Scott, C. E. et al. Protein Sci. 2013 , 22 , 101 - 113 ; Ahn, K. H. et al. Proteins 2013 , 81 , 1304 - 1317] are used here to predict the binding sites for known CB1-selective inverse agonists including rimonabant and its seven known derivatives. This binding pocket, which differs significantly from previously published models, is used to identify 16 novel compounds expected to be CB1 inverse agonists by exploiting potential new interactions. We show experimentally that two of these compounds exhibit inverse agonist properties including inhibition of basal and agonist-induced G-protein coupling activity, as well as an enhanced level of CB1 cell surface localization. This demonstrates the utility of using the predicted binding sites for an ensemble of CB1 receptor structures for designing new CB1 inverse agonists.

  3. Induction of proteinuria by cannabinoid receptors 1 signaling activation in CB1 transgenic mice.

    Science.gov (United States)

    Hsu, Yung-Chien; Lei, Chen-Chou; Shih, Ya-Hsueh; Ho, Cheng; Lin, Chun-Liang

    2015-02-01

    Proteinuria is not only a sign of kidney damage but is also involved in the progression of renal disease as an independent pathologic factor. Although patients with mutated type 1 cannabinoid receptors (CB1) polymorphism are associated with renal microvascular damage, the biologic role of CB1 signaling in proteinuria remains uncharacterized till now. Herein, we investigate whether CB1 participates in glomerular proteinuria in CB1 transgenic mice and treatment with CB1 agonist WIN55212-2 rat, neither of which are diabetic models. The CB1 transgenic mice and rats treated with CB1 agonist WIN55212-2 had higher kidney weight and urinary protein concentrations but not blood glucose levels compared with the wild-type group. A combination of laser-capture microsdissection, quantitative reverse transcription-polymerase chain reaction, immunoblotting and immunohistochemical validation revealed that CB1 transgenic mice and rats treated with CB1 agonist WIN55212-2 had higher vascular endothelial growth factor (VEGF) expression in renal glomeruli than that of the wild-type group. Geneticorpharmacological activation of CB1 by transgenic CB1 mice or treatment with WIN55212-2 reduced nephrin expression in the renal glomeruli compared with that of the wild-type group in the glomerular mesanglium. Taken together, CB1 transgenic mice and rats treated with CB1 agonist WIN55212-2 induced proteinuria with upregulation of CB1 resulting in impaired nephrin expression, by inducing excess VEGF reaction in the renal glomeruli. Genetic and pharmacological manipulation of CB1 signaling revealed VEGF-dependent nephrin depression of glomerulopathy. Controlling CB1 activity can be used an alternative strategy for sustaining renal function in the presence of CB1 activation.

  4. Biphasic effects of cannabinoids in anxiety responses: CB1 and GABA(B) receptors in the balance of GABAergic and glutamatergic neurotransmission.

    Science.gov (United States)

    Rey, Alejandro Aparisi; Purrio, Martin; Viveros, Maria-Paz; Lutz, Beat

    2012-11-01

    Biphasic effects of cannabinoids have been shown in processes such as feeding behavior, motor activity, motivational processes and anxiety responses. Using two different tests for the characterization of anxiety-related behavior (elevated plus-maze and holeboard), we first identified in wild-type C57BL/6N mice, two doses of the synthetic CB1 cannabinoid receptor agonist CP-55,940 with anxiolytic (1 μg/kg) and anxiogenic properties (50 μg/kg), respectively. To clarify the role of CB1 receptors in this biphasic effect, both doses were applied to two different conditional CB1 receptor knockout (KO) mouse lines, GABA-CB1-KO (CB1 receptor inactivation in forebrain GABAergic neurons) and Glu-CB1-KO (CB1 receptor inactivation in cortical glutamatergic neurons). We found that the anxiolytic-like effects of the low dose of cannabinoids are mediated via the CB1 receptor on cortical glutamatergic terminals, because this anxiolytic-like response was abrogated only in Glu-CB1-KO mice. On the contrary, the CB1 receptor on the GABAergic terminals is required to induce an anxiogenic-like effect under a high-dose treatment because of the fact that this effect was abolished specifically in GABA-CB1-KO mice. These experiments were carried out in both sexes, and no differences occurred with the doses tested in the mutant mice. Interestingly, the positive allosteric modulation of GABA(B) receptor with GS-39783 was found to largely abrogate the anxiogenic-like effect of the high dose of CP-55,940. Our results shed new light in further understanding the biphasic effects of cannabinoids at the molecular level and, importantly, pave the way for the development of novel anxiolytic cannabinoid drugs, which may have favorable effect profiles targeting the CB1 receptor on glutamatergic terminals.

  5. Synthetic Ligands of Cannabinoid Receptors Affect Dauer Formation in the Nematode Caenorhabditis elegans

    Science.gov (United States)

    Reis Rodrigues, Pedro; Kaul, Tiffany K.; Ho, Jo-Hao; Lucanic, Mark; Burkewitz, Kristopher; Mair, William B.; Held, Jason M.; Bohn, Laura M.; Gill, Matthew S.

    2016-01-01

    Under adverse environmental conditions the nematode Caenorhabditis elegans can enter an alternate developmental stage called the dauer larva. To identify lipophilic signaling molecules that influence this process, we screened a library of bioactive lipids and found that AM251, an antagonist of the human cannabinoid (CB) receptor, suppresses dauer entry in daf-2 insulin receptor mutants. AM251 acted synergistically with glucose supplementation indicating that the metabolic status of the animal influenced the activity of this compound. Similarly, loss of function mutations in the energy-sensing AMP-activated kinase subunit, aak-2, enhanced the dauer-suppressing effects of AM251, while constitutive activation of aak-2 in neurons was sufficient to inhibit AM251 activity. Chemical epistasis experiments indicated that AM251 acts via G-protein signaling and requires the TGF-β ligand DAF-7, the insulin peptides DAF-28 and INS-6, and a functional ASI neuron to promote reproductive growth. AM251 also required the presence of the SER-5 serotonin receptor, but in vitro experiments suggest that this may not be via a direct interaction. Interestingly, we found that other antagonists of mammalian CB receptors also suppress dauer entry, while the nonselective CB receptor agonist, O-2545, not only inhibited the activity of AM251, but also was able to promote dauer entry when administered alone. Since worms do not have obvious orthologs of CB receptors, the effects of synthetic CBs on neuroendocrine signaling in C. elegans are likely to be mediated via another, as yet unknown, receptor mechanism. However, we cannot exclude the existence of a noncanonical CB receptor in C. elegans. PMID:27172180

  6. Neuroprotection by the cannabinoid agonist WIN-55212 in an in vivo newborn rat model of acute severe asphyxia.

    Science.gov (United States)

    Martínez-Orgado, José; Fernández-Frutos, Beatriz; González, Rita; Romero, Eva; Urigüen, Leire; Romero, Julián; Viveros, M Paz

    2003-06-10

    This study was designed to evaluate the neuroprotective effect of the cannabinoid agonist WIN-55212 after inducing acute severe asphyxia in newborn rats. The left common carotid artery was ligated in anaesthetised 7-day-old Wistar rats, which were then asphyxiated by inhaling 100% nitrogen for 10 min. Pups recovering from asphyxia were s.c. administered vehicle (n=23), WIN-55212 (0.1 mg/kg, n=18), or WIN-55212 plus the CB1 receptor antagonist SR141716 (3 mg/kg, n=10). Pups undergoing a sham operation served as controls (n=12). Coronal sections of the brain were obtained on the 14th day after surgery and observed under light microscope after Nissl or Fluoro-Jade B (FJB) staining, to respectively quantify surviving or degenerating neurones in the CA1 area of the hippocampus and parietal cortex. Acute asphyxia led to early neurone loss amounting to 19% in the hippocampus and 29% in the cortex (both ANOVA P<0.05 vs. control). Delayed neurone loss occurred in the proportions 13% in the hippocampus and 20% in the cortex (both ANOVA P<0.05 vs. control). Neuronal loss was fully prevented by WIN-55212 administration. Co-administration of SR141716 failed to modify the protective effect of WIN-55212 on early neuronal death, but abolished the WIN-55212-induced prevention of delayed neuronal death. We conclude that when administered after acute severe asphyxia in newborn rats, WIN-55212 shows a neuroprotective effect, reducing both early and delayed neurone loss. This effect is achieved through two parallel CB1-dependent and -independent mechanisms.

  7. Prevention of Paclitaxel-Induced Neuropathy Through Activation of the Central Cannabinoid Type 2 Receptor System

    Science.gov (United States)

    Naguib, Mohamed; Xu, Jijun J.; Diaz, Philippe; Brown, David L.; Cogdell, David; Bie, Bihua; Hu, Jianhua; Craig, Suzanne; Hittelman, Walter N.

    2012-01-01

    Background Peripheral neuropathy is a major dose-limiting toxicity of chemotherapy, especially after multiple courses of paclitaxel. The development of paclitaxel-induced neuropathy is associated with the activation of microglia followed by the activation and proliferation of astrocytes, and the expression and release of proinflammatory cytokines in the spinal dorsal horn. Cannabinoid type 2 (CB2) receptors are expressed in the microglia in neurodegenerative disease models. Methods To explore the potential of CB2 agonists for preventing paclitaxel-induced neuropathy, we designed and synthesized a novel CB2-selective agonist, namely MDA7. The effect of MDA7 in preventing paclitaxel-induced allodynia was assessed in rats and in CB2+/+ and CB2–/– mice. We hypothesize that the CB2 receptor functions in a negative-feedback loop and that early MDA7 administration can blunt the neuroinflammatory response to paclitaxel and prevent mechanical allodynia through interference with specific signaling pathways. Results We found that MDA7 prevents paclitaxel-induced mechanical allodynia in rats and mice in a dose- and time-dependent manner without compromising paclitaxel's antineoplastic effect. MDA7's neuroprotective effect was absent in CB2-/- mice and was blocked by CB2 antagonists, suggesting that MDA7's action directly involves CB2 receptor activation. MDA7 treatment was found to interfere with early events in the paclitaxel-induced neuroinflammatory response as evidenced by relatively reduced Toll-like receptor and CB2 expression in the lumbar spinal cord, reduced levels of extracellular signal regulated kinase 1/2 activity, reduced numbers of activated microglia and astrocytes, and reduced secretion of proinflammatory mediators in vivo and in in vitro models. Conclusions Our findings suggest an innovative therapeutic approach to prevent chemotherapy-induced neuropathy and may permit more aggressive use of active chemotherapeutic regimens with reduced long-term sequelae

  8. CB1 and CB2 cannabinoid receptor expression during development and in epileptogenic developmental pathologies

    NARCIS (Netherlands)

    E. Zurolo; A.M. Iyer; W.G.M. Spliet; P.C. van Rijen; D. Troost; J.A. Gorter; E. Aronica

    2010-01-01

    Recent data support the involvement of the endocannabinoid signaling in early brain development, as well as a key role of cannabinoid receptors (CBR) in pathological conditions associated with unbalanced neuronal excitability and inflammation. Using immunocytochemistry, we explored the expression an

  9. The neuronal distribution of cannabinoid receptor type 1 in the trigeminal ganglion of the rat.

    Science.gov (United States)

    Price, T J; Helesic, G; Parghi, D; Hargreaves, K M; Flores, C M

    2003-01-01

    Cannabinoid compounds have been shown to produce antinociception and antihyperalgesia by acting upon cannabinoid receptors located in both the CNS and the periphery. A potential mechanism by which cannabinoids could inhibit nociception in the periphery is the activation of cannabinoid receptors located on one or more classes of primary nociceptive neurons. To address this hypothesis, we evaluated the neuronal distribution of cannabinoid receptor type 1 (CB1) in the trigeminal ganglion (TG) of the adult rat through combined in situ hybridization (ISH) and immunohistochemistry (IHC). CB1 receptor mRNA was localized mainly to medium and large diameter neurons of the maxillary and mandibular branches of the TG. Consistent with this distribution, in a de facto nociceptive sensory neuron population that exhibited vanilloid receptor type 1 immunoreactivity, colocalization with CB1 mRNA was also sparse (CB1 mRNA. In contrast, and consistent with the neuron-size distribution for CB1, nearly 75% of CB1-positive neurons exhibited N52-immunoreactivity, a marker of myelinated axons. These results indicate that in the rat TG, CB1 receptors are expressed predominantly in neurons that are not thought to subserve nociceptive neurotransmission in the noninjured animal. Taken together with the absence of an above background in situ signal for CB2 mRNA in TG neurons, these findings suggest that the peripherally mediated antinociceptive effects of cannabinoids may involve either as yet unidentified receptors or interaction with afferent neuron populations that normally subserve non-nociceptive functions.

  10. Interaction between Cannabinoid System and Toll-Like Receptors Controls Inflammation.

    Science.gov (United States)

    McCoy, Kathleen L

    2016-01-01

    Since the discovery of the endocannabinoid system consisting of cannabinoid receptors, endogenous ligands, and biosynthetic and metabolizing enzymes, interest has been renewed in investigating the promise of cannabinoids as therapeutic agents. Abundant evidence indicates that cannabinoids modulate immune responses. An inflammatory response is triggered when innate immune cells receive a danger signal provided by pathogen- or damage-associated molecular patterns engaging pattern-recognition receptors. Toll-like receptor family members are prominent pattern-recognition receptors expressed on innate immune cells. Cannabinoids suppress Toll-like receptor-mediated inflammatory responses. However, the relationship between the endocannabinoid system and innate immune system may not be one-sided. Innate immune cells express cannabinoid receptors and produce endogenous cannabinoids. Hence, innate immune cells may play a role in regulating endocannabinoid homeostasis, and, in turn, the endocannabinoid system modulates local inflammatory responses. Studies designed to probe the interaction between the innate immune system and the endocannabinoid system may identify new potential molecular targets in developing therapeutic strategies for chronic inflammatory diseases. This review discusses the endocannabinoid system and Toll-like receptor family and evaluates the interaction between them. PMID:27597805

  11. CB1 cannabinoid receptor-mediated modulation of food intake in mice

    OpenAIRE

    Wiley, Jenny L; Burston, James J.; Leggett, Darnica C; Alekseeva, Olga O; Razdan, Raj K.; Mahadevan, Anu; Martin, Billy R

    2005-01-01

    Marijuana's appetite-increasing effects have long been known. Recent research suggests that the CB1 cannabinoid receptor antagonist SR141716A may suppress appetite. This study represents a further, systematic investigation of the role of CB1 cannabinoid receptors in the pharmacological effects of cannabinoids on food intake.Mice were food-restricted for 24 h and then allowed access to their regular rodent chow for 1 h. Whereas the CB1 antagonist SR141716A dose-dependently decreased food consu...

  12. Comparative effects of chlorpyrifos in wild type and cannabinoid Cb1 receptor knockout mice

    Energy Technology Data Exchange (ETDEWEB)

    Baireddy, Praveena; Liu, Jing; Hinsdale, Myron; Pope, Carey, E-mail: carey.pope@okstate.edu

    2011-11-15

    Endocannabinoids (eCBs) modulate neurotransmission by inhibiting the release of a variety of neurotransmitters. The cannabinoid receptor agonist WIN 55.212-2 (WIN) can modulate organophosphorus (OP) anticholinesterase toxicity in rats, presumably by inhibiting acetylcholine (ACh) release. Some OP anticholinesterases also inhibit eCB-degrading enzymes. We studied the effects of the OP insecticide chlorpyrifos (CPF) on cholinergic signs of toxicity, cholinesterase activity and ACh release in tissues from wild type (+/+) and cannabinoid CB1 receptor knockout (-/-) mice. Mice of both genotypes (n = 5-6/treatment group) were challenged with CPF (300 mg/kg, 2 ml/kg in peanut oil, sc) and evaluated for functional and neurochemical changes. Both genotypes exhibited similar cholinergic signs and cholinesterase inhibition (82-95% at 48 h after dosing) in cortex, cerebellum and heart. WIN reduced depolarization-induced ACh release in vitro in hippocampal slices from wild type mice, but had no effect in hippocampal slices from knockouts or in striatal slices from either genotype. Chlorpyrifos oxon (CPO, 100 {mu}M) reduced release in hippocampal slices from both genotypes in vitro, but with a greater reduction in tissues from wild types (21% vs 12%). CPO had no significant in vitro effect on ACh release in striatum. CPF reduced ACh release in hippocampus from both genotypes ex vivo, but reduction was again significantly greater in tissues from wild types (52% vs 36%). In striatum, CPF led to a similar reduction (20-23%) in tissues from both genotypes. Thus, while CB1 deletion in mice had little influence on the expression of acute toxicity following CPF, CPF- or CPO-induced changes in ACh release appeared sensitive to modulation by CB1-mediated eCB signaling in a brain-regional manner. -- Highlights: Black-Right-Pointing-Pointer C57Bl/6 mice showed dose-related cholinergic toxicity following subcutaneous chlorpyrifos exposure. Black-Right-Pointing-Pointer Wild type and

  13. Type 2 cannabinoid receptor contributes to the physiological regulation of spermatogenesis.

    Science.gov (United States)

    Di Giacomo, Daniele; De Domenico, Emanuela; Sette, Claudio; Geremia, Raffaele; Grimaldi, Paola

    2016-04-01

    Type 2 cannabinoid receptor (CB2) has been proposed to play a pivotal role in meiotic entry of male germ cells, similar to retinoic acid (RA). In this study, we showed that activation of CB2with the specific agonist JWH133 [3-(1',1'-dimethylbutyl)-1-deoxy-8-THC] (IC5010(-6)M) mimics epigenetic events induced by RA (IC5010(-7)M) in spermatogonia. Both JWH133 and RA treatments stimulate the expression of the meiotic genes c-KitandStra8, by up-regulating H3K4me3 and down-regulating H3K9me2 levels in genomic regions flanking the transcription start site. Moreover, both agents increase the expression ofPrdm9, the gene encoding a meiosis-specific histone, H3K4me3 methyltransferase, which marks hotspots of recombination in prophase I, thus resulting in a global increase in H3K4me3. Notably, prolonged administration of JWH133 to immature 7 dpp CD-1 mice induced an acceleration of the onset of spermatogenesis, whereas the specific CB2antagonist delayed germ cell differentiation. Thus, both hyper- and hypostimulation of CB2disrupted the temporal dynamics of the spermatogenic cycle. These findings highlight the importance of proper CB2signaling for the maintenance of a correct temporal progression of spermatogenesis and suggest a possible adverse effect of cannabis in deregulating this process.-Di Giacomo, D., De Domenico, E., Sette, C., Geremia, R., Grimaldi, P. Type 2 cannabinoid receptor contributes to the physiological regulation of spermatogenesis. PMID:26671998

  14. Global Fold of Human Cannabinoid Type 2 Receptor Probed by Solid-State 13C-, 15N-MAS NMR and Molecular Dynamics Simulations

    OpenAIRE

    Kimura, Tomohiro; Vukoti, Krishna; Lynch, Diane L.; Hurst, Dow P.; Grossfield, Alan; Pitman, Michael C.; Reggio, Patricia H.; Yeliseev, Alexei A.; Gawrisch, Klaus

    2013-01-01

    The global fold of human cannabinoid type 2 (CB2) receptor in the agonist-bound active state in lipid bilayers was investigated by solid-state 13C- and 15N magic-angle spinning (MAS) NMR, in combination with chemical-shift prediction from a structural model of the receptor obtained by microsecond-long molecular dynamics (MD) simulations. Uniformly 13C-, and 15N-labeled CB2 receptor was expressed in milligram quantities by bacterial fermentation, purified, and functionally reconstituted into l...

  15. Combining GLP-1 receptor agonists with insulin

    DEFF Research Database (Denmark)

    Holst, Jens Juul; Vilsbøll, T

    2013-01-01

    physicians and patients regarding the initiation and intensification of insulin therapy, in part due to concerns about the associated weight gain and increased risk of hypoglycaemia. Glucagon-like peptide-1 receptor agonists (GLP-1RAs) increase insulin release and suppress glucagon secretion in a glucose......Due to the increasing prevalence of type 2 diabetes mellitus (T2DM), the emergent trend towards diagnosis in younger patients and the progressive nature of this disease, many more patients than before now require insulin to maintain glycaemic control. However, there is a degree of inertia among......, compared with insulin, the antihyperglycaemic efficacy of GLP-1RAs is limited. The combination of a GLP-1RA and insulin might thus be highly effective for optimal glucose control, ameliorating the adverse effects typically associated with insulin. Data from clinical studies support the therapeutic...

  16. Differential effects of repeated low dose treatment with the cannabinoid agonist WIN 55,212-2 in experimental models of bone cancer pain and neuropathic pain

    DEFF Research Database (Denmark)

    Hald, Andreas; Ding, Ming; Egerod, Kristoffer Lihme;

    2008-01-01

    Pain due to bone malignancies is one of the most difficult types of cancer pain to fully control and may further decrease the patients' quality of life. Animal models of chronic pain conditions resulting from peripheral inflammatory reactions or nerve injuries are responsive to treatment....... Furthermore, this treatment strategy was not found to induce measurable CNS related side effects or tolerance. Cancer cell viability assays and bone volume fraction assessed by micro computed tomography (microCT) demonstrated that these effects were not due to changes in cancer progression. The difference...... with cannabinoid agonists. However, the use of cannabinoid agonists in humans may be hampered by CNS related side effects and development of tolerance. In the present study, we investigated the effect of repeated low dose administration of the synthetic cannabinoid agonist WIN 55,212-2 on bone cancer pain...

  17. Distribution of cannabinoid receptor 1 in the CNS of zebrafish.

    Science.gov (United States)

    Lam, C S; Rastegar, S; Strähle, U

    2006-01-01

    The cannabinoid receptor 1 (Cb1) mediates the psychoactive effect of marijuana. In mammals, there is abundant evidence advocating the importance of cannabinoid signaling; activation of Cb1 exerts diverse functions, chiefly by its ability to modulate neurotransmission. Thus, much attention has been devoted to understand its role in health and disease and to evaluate its therapeutic potential. Here, we have cloned zebrafish cb1 and investigated its expression in developing and adult zebrafish brain. Sequence analysis showed that there is a high degree of conservation, especially in residues demonstrated to be critical for function in mammals. In situ hybridization revealed that zebrafish cb1 appears first in the preoptic area at 24 hours post-fertilization. Subsequently, transcripts are detected in the dorsal telencephalon, hypothalamus, pretectum and torus longitudinalis. A similar pattern of expression is recapitulated in the adult brain. While cb1 is intensively stained in the medial zone of the dorsal telencephalon, expression elsewhere is weak by comparison. In particular, localization of cb1 in the telencephalic periventricular matrix is suggestive of the involvement of Cb1 in neurogenesis, bearing strong resemblance in terms of expression and function to the proliferative mammalian hippocampal formation. In addition, a gradient-like expression of cb1 is detected in the torus longitudinalis, a teleost specific neural tissue. In relation to dopaminergic neurons in the diencephalic posterior tuberculum (considered to be the teleostean homologue of the mammalian midbrain dopaminergic system), both cb1 and tyrosine hydroxylase-expressing cells occupy non-overlapping domains. However there is evidence that they are co-localized in the caudal zone of the hypothalamus, implying a direct modulation of dopamine release in this particular region. Collectively, our data indicate the propensity of zebrafish cb1 to participate in multiple neurological processes.

  18. The Role of Cannabinoid Receptors in the Descending Modulation of Pain

    Directory of Open Access Journals (Sweden)

    Francesco Rossi

    2010-08-01

    Full Text Available The endogenous antinociceptive descending pathway represents a circuitry of the supraspinal central nervous system whose task is to counteract pain. It includes the periaqueductal grey (PAG-rostral ventromedial medulla (RVM-dorsal horn (DH axis, which is the best characterized pain modulation system through which pain is endogenously inhibited. Thus, an alternative rational strategy for silencing pain is the activation of this anatomical substrate. Evidence of the involvement of cannabinoid receptors (CB in the supraspinal modulation of pain can be found in several studies in which intra-cerebral microinjections of cannabinoid ligands or positive modulators have proved to be analgesic in different pain models, whereas cannabinoid receptor antagonists or antisense nucleotides towards CB1 receptors have facilitated pain. Like opioids, cannabinoids produce centrally-mediated analgesia by activating a descending pathway which includes PAG and its projection to downstream RVM neurons, which in turn send inhibitory projections to the dorsal horn of the spinal cord. Indeed, several studies underline a supraspinal regulation of cannabinoids on g-aminobutyric acid (GABA and glutamate release which inhibit and enhance the antinociceptive descending pathway, respectively. Cannabinoid receptor activation expressed on presynaptic GABAergic terminals reduces the probability of neurotransmitter release thus dis-inhibiting the PAG-RVM-dorsal horn antinociceptive pathway. Cannabinoids seem to increase glutamate release (maybe as consequence of GABA decrease and to require glutamate receptor activation to induce antinociception. The consequent outcome is behavioral analgesia, which is reproduced in several pain conditions, from acute to chronic pain models such as inflammatory and neuropathic pain. Taken together these findings would suggest that supraspinal cannabinoid receptors have broad applications, from pain control to closely related central nervous system

  19. 大麻素受体2激动剂JWH015对瑞芬太尼诱发痛觉过敏的影响%The effect of cannabinoid receptor 2 agonist JWH015 on the hyperalgesia induced by remifentanil

    Institute of Scientific and Technical Information of China (English)

    张威; 张伟; 刘晓杰; 张娟; 蒋明; 马正良; 顾小萍

    2012-01-01

    目的 探讨大麻素受体2( cannabinoid receptor 2,CB2R)激动剂JWH015对瑞芬太尼诱发的切口痛模型大鼠痛觉过敏的影响.方法 60只雄性SD大鼠采用随机数字表法随机分成2大组:鞘内给药组和腹腔给药组.每大组又随机分为5小组:鞘内给药组分为对照组1(C1组)、切口痛组1(I1组)、瑞芬太尼组1(R1组)、切口痛+JWH015组(QI组)、切口痛+瑞芬太尼+JWH015组(QR组);腹腔给药组分为对照组2(C2组)、切口痛组2(I2组)、瑞芬太尼组2(R2组)、切口痛+JWH015组(FI组),切口痛+瑞芬太尼+ JWH015组(FR组),每组6只.QI组与QR组在造模前30 min鞘内注射10μg JWH015,C1、I1、R1组均鞘内给予20%的二甲基亚砜(DMSO)溶液,容积均为10μl;而FI组与FR组在造模前30 min腹腔注射100 μg JWH015,C2、I2、R2组均腹腔给予4%的DMSO溶液,容积均为0.5ml.除C1/C2组外,其余各组均制作切口痛模型,R1/R2组、QR组和FR组在造模的同时皮下泵注瑞芬太尼0.04 mg/kg,其余组皮下泵注生理盐水,容积均为0.4ml,30 min泵完.测量术前24h及术后2,6,24,48 h大鼠手术切口同侧后爪的机械缩足反射阈值(PWMT)及热缩足潜伏期(PWTL).结果 与C1/C2组和基础值比较,I1/I2组术后PWMT和PWTL均降低(P<0.01);与I1/I2组比较,R1/R2组术后PWMT和PWTL均明显降低(P<0.05);与R1/R2组相比,QR组从术后6h的PWMT[ (7.78±1.09)g]和PWTL[( 17.28±1.58)s]开始明显升高(P<0.05),与FR组在术后6h、24h和48 h的PWMT[ (7.79 ±0.72)g,(9.50±1.17)g,(7.86±1.16)g]和PWTL[ (16.23±1.50)s,(19.53±1.63)s,(18.10 ±0.93)s]升高的结果一致.结论 鞘内及腹腔注射JW H015均可以有效缓解由瑞芬太尼诱发的切口周围组织痛觉过敏.%Objective To investigate the effects of cannabinoid receptor 2 (cannabinoid receptor 2,CB2R) agonist JWHO15 on the hyperalgesia induced by remifentanil in a rat model of postoperative pain.Methods Sixty SD rats were randomly divided into 10 groups ( n =6 each

  20. Brain neuronal CB2 cannabinoid receptors in drug abuse and depression: from mice to human subjects.

    Directory of Open Access Journals (Sweden)

    Emmanuel S Onaivi

    Full Text Available BACKGROUND: Addiction and major depression are mental health problems associated with stressful events in life with high relapse and reoccurrence even after treatment. Many laboratories were not able to detect the presence of cannabinoid CB2 receptors (CB2-Rs in healthy brains, but there has been demonstration of CB2-R expression in rat microglial cells and other brain associated cells during inflammation. Therefore, neuronal expression of CB2-Rs had been ambiguous and controversial and its role in depression and substance abuse is unknown. METHODOLOGY/PRINCIPAL FINDINGS: In this study we tested the hypothesis that genetic variants of CB2 gene might be associated with depression in a human population and that alteration in CB2 gene expression may be involved in the effects of abused substances including opiates, cocaine and ethanol in rodents. Here we demonstrate that a high incidence of (Q63R but not (H316Y polymorphism in the CB2 gene was found in Japanese depressed subjects. CB2-Rs and their gene transcripts are expressed in the brains of naïve mice and are modulated following exposure to stressors and administration of abused drugs. Mice that developed alcohol preference had reduced CB2 gene expression and chronic treatment with JWH015 a putative CB2-R agonist, enhanced alcohol consumption in stressed but not in control mice. The direct intracerebroventricular microinjection of CB2 anti-sense oligonucleotide into the mouse brain reduced mouse aversions in the plus-maze test, indicating the functional presence of CB2-Rs in the brain that modifies behavior. We report for the using electron microscopy the sub cellular localization of CB2-Rs that are mainly on post-synaptic elements in rodent brain. CONCLUSIONS/SIGNIFICANCE: Our data demonstrate the functional expression of CB2-Rs in brain that may provide novel targets for the effects of cannabinoids in depression and substance abuse disorders beyond neuro-immunocannabinoid activity.

  1. Cannabinoid Receptors Are Overexpressed in CLL but of Limited Potential for Therapeutic Exploitation.

    Science.gov (United States)

    Freund, Patricia; Porpaczy, Edit A; Le, Trang; Gruber, Michaela; Pausz, Clemens; Staber, Philipp; Jäger, Ulrich; Vanura, Katrina

    2016-01-01

    The cannabinoid receptors 1 and 2 (CNR1&2) are overexpressed in a variety of malignant diseases and cannabinoids can have noteworthy impact on tumor cell viability and tumor growth. Patients diagnosed with chronic lymphocytic leukemia (CLL) present with very heterogeneous disease characteristics translating into highly differential risk properties. To meet the urgent need for refinement in risk stratification at diagnosis and the search for novel therapies we studied CNR expression and response to cannabinoid treatment in CLL. Expression levels of CNR1&2 were determined in 107 CLL patients by real-time PCR and analyzed with regard to prognostic markers and survival. Cell viability of primary CLL cells was determined in suspension and co-culture after incubation in increasing cannabinoid concentrations under normal and reduced serum conditions and in combination with fludarabine. Impact of cannabinoids on migration of CLL cells towards CXCL12 was determined in transwell plates. We found CNR1&2 to be overexpressed in CLL compared to healthy B-cells. Discriminating between high and low expressing subgroups, only high CNR1 expression was associated with two established high risk markers and conferred significantly shorter overall and treatment free survival. Viability of CLL primary cells was reduced in a dose dependent fashion upon incubation with cannabinoids, however, healthy cells were similarly affected. Under serum reduced conditions, no significant differences were observed within suspension and co-culture, respectively, however, the feeder layer contributed significantly to the survival of CLL cells compared to suspension culture conditions. No significant differences were observed when treating CLL cells with cannabinoids in combination with fludarabine. Interestingly, biologic activity of cannabinoids was independent of both CNR1&2 expression. Finally, we did not observe an inhibition of CXCL12-induced migration by cannabinoids. In contrast to other tumor

  2. Design, synthesis and evaluation of fluorescent CB2 cannabinoid receptor ligands

    OpenAIRE

    Holt, Christopher James

    2009-01-01

    Cannabis has been used as a medicinal and natural product for thousands of years. Whether it has been used to make rope or paper, or been used to treat pain or depression, cannabis has always had a place in human civilisation. With the isolation of the psychoactive compounds responsible for cannabis’ effects, the discovery of two human cannabinoid receptors and an expanding knowledge of the therapeutic uses of cannabis, interest in the development of novel cannabinoids grew. The CB2 cann...

  3. The endocannabinoid N-arachidonoyldopamine (NADA) exerts neuroprotective effects after excitotoxic neuronal damage via cannabinoid receptor 1 (CB(1)).

    Science.gov (United States)

    Grabiec, Urszula; Koch, Marco; Kallendrusch, Sonja; Kraft, Robert; Hill, Kerstin; Merkwitz, Claudia; Ghadban, Chalid; Lutz, Beat; Straiker, Alex; Dehghani, Faramarz

    2012-03-01

    Endocannabinoids exert numerous effects in the CNS under physiological and pathological conditions. The aim of the present study was to examine whether the endocannabinoid N-arachidonoyldopamine (NADA) may protect neurons in excitotoxically lesioned organotypic hippocampal slice cultures (OHSC). OHSC were excitotoxically lesioned by application of N-methyl-d-aspartate (NMDA, 50 μM) for 4 h and subsequently treated with different NADA concentrations (0.1 pM-50 μM) alone or in combination with cannabinoid receptor antagonists. NADA protected dentate gyrus granule cells and caused a slight reduction in the number of microglial cells. The number of degenerated neurons significantly decreased between 100 pM and 10 μM NADA (p NADA mediated neuroprotection, we applied the cannabinoid (CB) receptor 1 (CB(1)) inverse agonist/antagonist AM251, CB(2) inverse agonist/antagonist AM630, abnormal-cannabidiol (abn-CBD)-sensitive receptor antagonist O-1918, transient receptor potential channel V1 (TRPV1) antagonist 6-iodonordihydrocapsaicin and A1 (TRPA1) antagonist HC-030031. Neuroprotective properties of low (1 nM) but not high (10 μM) NADA concentrations were solely blocked by AM251 and were absent in CB(1)(-/-) mice. AM630, O-1918, 6-iodonordihydrocapsaicin and HC-030031 showed no effects at all NADA concentrations applied. Our findings demonstrate that NADA protects dentate gyrus granule cells by acting via CB(1). NADA reduced the number of microglial cells at distinct concentrations. TRPV1 and TRPA1 were not involved in NADA mediated neuroprotection. Thus, our data implicate that NADA mediated activation of neuronal CB(1) may serve as a novel pharmacological target to mitigate symptoms of neuronal damage.

  4. Unique interaction pattern for a functionally biased ghrelin receptor agonist

    DEFF Research Database (Denmark)

    Sivertsen, Bjørn Behrens; Lang, Manja; Frimurer, Thomas M.;

    2011-01-01

    Based on the conformationally constrained D-Trp-Phe-D-Trp (wFw) core of the prototype inverse agonist [D-Arg(1),D-Phe(5),D-Trp(7,9),Leu(11)]substance P, a series of novel, small, peptide-mimetic agonists for the ghrelin receptor were generated. By using various simple, ring-constrained spacers co...

  5. GABAA receptor partial agonists and antagonists

    DEFF Research Database (Denmark)

    Krall, Jacob; Balle, Thomas; Krogsgaard-Larsen, Niels;

    2015-01-01

    antagonists and describes the development of potent antagonists from partial agonists originally derived from the potent GABAAR agonist muscimol. In this process, several heterocyclic aromatic systems have been used in combination with structural models in order to map the orthosteric binding site...... and to reveal structural details to be used for obtaining potency and subtype selectivity. The challenges connected to functional characterization of orthosteric GABAAR partial agonists and antagonists, especially with regard to GABAAR stoichiometry and alternative binding sites are discussed. GABAAR...

  6. Frequency-dependent cannabinoid receptor-independent modulation of glycine receptors by endocannabinoid 2-AG

    Directory of Open Access Journals (Sweden)

    Natalia eLozovaya

    2011-07-01

    Full Text Available Endocannabinoids are known as retrograde messengers, being released from the postsynaptic neuron and acting on specific presynaptic G-protein-coupled cannabinoid (CB receptors to decrease neurotransmitter release. Also, at physiologically relevant concentrations cannabinoids can directly modulate the function of voltage-gated and receptor-operated ion channels. Using patch-clamp recording we analyzed the consequences of the direct action of an endocannabinoid, 2-arachidonoylglycerol (2-AG, on the functional properties of glycine receptor channels (GlyRs and ionic currents in glycinergic synapses. At physiologically relevant concentrations (0.1-1 µM, 2-AG directly affected the functions of recombinant homomeric alpha1H GlyR: it inhibited peak amplitude and dramatically enhanced desensitization. The action of 2-AG on GlyR-mediated currents developed rapidly, within ~300 milliseconds. Addition of 1 µM 2-AG strongly facilitated the depression of glycine-induced currents during repetitive (4-10 Hz application of short (2-ms duration pulses of glycine to outside-out patches. In brainstem slices from CB1 receptor-knockout mice, 2-AG significantly decreased the extent of facilitation of synaptic currents in hypoglossal motoneurons during repetitive (10-20 Hz stimulation. These observations suggest that endocannabinoids can modulate postsynaptic metaplasticity of glycinergic synaptic currents in a CB1 receptor-independent manner.

  7. Experimental Cannabinoid 2 Receptor-Mediated Immune Modulation in Sepsis

    Directory of Open Access Journals (Sweden)

    J. Sardinha

    2014-01-01

    Full Text Available Sepsis is a complex condition that results from a dysregulated immune system in response to a systemic infection. Current treatments lack effectiveness in reducing the incidence and mortality associated with this disease. The endocannabinoid system offers great promise in managing sepsis pathogenesis due to its unique characteristics. The present study explored the effect of modulating the CB2 receptor pathway in an acute sepsis mouse model. Endotoxemia was induced by intravenous injection of lipopolysaccharide (LPS in mice and intestinal microcirculation was assessed through intravital microscopy. We found that HU308 (CB2 receptor agonist reduced the number of adherent leukocytes in submucosal venules but did not restore muscular and mucosal villi FCD in endotoxemic mice. AM630 (CB2 receptor antagonist maintained the level of adherent leukocytes induced by LPS but further reduced muscular and mucosal villi FCD. URB597 (FAAH inhibitor and JZL184 (MAGL inhibitor both reduced the number of adherent leukocytes in submucosal venules but did not restore the mucosal villi FCD. Using various compounds we have shown different mechanisms of activating CB2 receptors to reduce leukocyte endothelial interactions in order to prevent further inflammatory damage during sepsis.

  8. Synthetic and endogenous cannabinoids protect retinal neurons from AMPA excitotoxicity in vivo, via activation of CB1 receptors: Involvement of PI3K/Akt and MEK/ERK signaling pathways.

    Science.gov (United States)

    Kokona, Despina; Thermos, Kyriaki

    2015-07-01

    Cannabinoids have been suggested to protect retinal ganglion cells in different models of toxicity, but their effects on other retinal neurons are poorly known. We investigated the neuroprotective actions of the endocannabinoid N-arachidonoyl ethanolamine (Anandamide/AEA) and the synthetic cannabinoids R1-Methanandamide (MethAEA) and HU-210, in an in vivo retinal model of AMPA excitotoxicity, and the mechanisms involved in the neuroprotection. Sprague-Dawley rats were intravitreally injected with PBS or AMPA in the absence or presence of the cannabinoid agonists. Brain nitric oxide synthase (bNOS) and choline acetyltransferase (ChAT) immunoreactivity (IR), as well as TUNEL staining, assessed the AMPA-induced retinal amacrine cell loss and the dose-dependent neuroprotection afforded by cannabinoids. The CB1 receptor selective antagonist AM251 and the PI3K/Akt inhibitor wortmannin reversed the cannabinoid-induced neuroprotection, suggesting the involvement of CB1 receptors and the PI3K/Akt pathway in cannabinoids' actions. Experiments with the CB2 agonist JWH015 and [(3)H]CP55940 radioligand binding suggested that the CB2 receptor is not involved in the neuroprotection. AEA and HU-210 induced phosphorylation of Akt but only AEA induced phosphorylation of ERK1/2 kinases, as revealed by western blot analysis. To investigate the role of caspase-3 in the AMPA-induced cell death, the caspase-3 inhibitor Z-DEVD-FMK was co-injected with AMPA. Z-DEVD-FMK had no effect on AMPA excitotoxicity. Moreover, no difference was observed in the phosphorylation of SAPK/JNK kinases between PBS- and AMPA-treated retinas. These results suggest that endogenous and synthetic cannabinoids protect retinal amacrine neurons from AMPA excitotoxicity in vivo via a mechanism involving the CB1 receptors, and the PI3K/Akt and/or MEK/ERK1/2 signaling pathways.

  9. Synthetic cannabinoids: In silico prediction of the cannabinoid receptor 1 affinity by a quantitative structure-activity relationship model.

    Science.gov (United States)

    Paulke, Alexander; Proschak, Ewgenij; Sommer, Kai; Achenbach, Janosch; Wunder, Cora; Toennes, Stefan W

    2016-03-14

    The number of new synthetic psychoactive compounds increase steadily. Among the group of these psychoactive compounds, the synthetic cannabinoids (SCBs) are most popular and serve as a substitute of herbal cannabis. More than 600 of these substances already exist. For some SCBs the in vitro cannabinoid receptor 1 (CB1) affinity is known, but for the majority it is unknown. A quantitative structure-activity relationship (QSAR) model was developed, which allows the determination of the SCBs affinity to CB1 (expressed as binding constant (Ki)) without reference substances. The chemically advance template search descriptor was used for vector representation of the compound structures. The similarity between two molecules was calculated using the Feature-Pair Distribution Similarity. The Ki values were calculated using the Inverse Distance Weighting method. The prediction model was validated using a cross validation procedure. The predicted Ki values of some new SCBs were in a range between 20 (considerably higher affinity to CB1 than THC) to 468 (considerably lower affinity to CB1 than THC). The present QSAR model can serve as a simple, fast and cheap tool to get a first hint of the biological activity of new synthetic cannabinoids or of other new psychoactive compounds. PMID:26795018

  10. Evaluation of the specificity of antibodies raised against cannabinoid receptor type 2 in the mouse retina

    DEFF Research Database (Denmark)

    Cécyre, Bruno; Thomas, Sébastien; Ptito, Maurice;

    2014-01-01

    Cannabinoid receptors (CB1R and CB2R) are among the most abundant G protein-coupled receptors in the central nervous system. The endocannabinoid system is an attractive therapeutic target for immune system modulation and peripheral pain management. While CB1R is distributed in the nervous system...

  11. Cannabinoid- and lysophosphatidylinositol-sensitive receptor GPR55 boosts neurotransmitter release at central synapses.

    Science.gov (United States)

    Sylantyev, Sergiy; Jensen, Thomas P; Ross, Ruth A; Rusakov, Dmitri A

    2013-03-26

    G protein-coupled receptor (GPR) 55 is sensitive to certain cannabinoids, it is expressed in the brain and, in cell cultures, it triggers mobilization of intracellular Ca(2+). However, the adaptive neurobiological significance of GPR55 remains unknown. Here, we use acute hippocampal slices and combine two-photon excitation Ca(2+) imaging in presynaptic axonal boutons with optical quantal analysis in postsynaptic dendritic spines to find that GPR55 activation transiently increases release probability at individual CA3-CA1 synapses. The underlying mechanism involves Ca(2+) release from presynaptic Ca(2+) stores, whereas postsynaptic stores (activated by spot-uncaging of inositol 1,4,5-trisphosphate) remain unaffected by GPR55 agonists. These effects are abolished by genetic deletion of GPR55 or by the GPR55 antagonist cannabidiol, a constituent of Cannabis sativa. GPR55 shows colocalization with synaptic vesicle protein vesicular glutamate transporter 1 in stratum radiatum. Short-term potentiation of CA3-CA1 transmission after a short train of stimuli reveals a presynaptic, Ca(2+) store-dependent component sensitive to cannabidiol. The underlying cascade involves synthesis of phospholipids, likely in the presynaptic cell, but not the endocannabinoids 2-arachidonoylglycerol or anandamide. Our results thus unveil a signaling role for GPR55 in synaptic circuits of the brain.

  12. Cannabinoid Receptor Activation Shifts Temporally Engendered Patterns of Dopamine Release

    OpenAIRE

    Oleson, Erik B.; Cachope, Roger; Fitoussi, Aurelie; Tsutsui, Kimberly; Wu, Sharon; Gallegos, Jacqueline A; Cheer, Joseph F.

    2014-01-01

    The ability to discern temporally pertinent environmental events is essential for the generation of adaptive behavior in conventional tasks, and our overall survival. Cannabinoids are thought to disrupt temporally controlled behaviors by interfering with dedicated brain timing networks. Cannabinoids also increase dopamine release within the mesolimbic system, a neural pathway generally implicated in timing behavior. Timing can be assessed using fixed-interval (FI) schedules, which reinforce b...

  13. Cannabinoid receptor agonism suppresses tremor, cognition disturbances and anxiety-like behaviors in a rat model of essential tremor.

    Science.gov (United States)

    Abbassian, Hassan; Esmaeili, Parisa; Tahamtan, Mahshid; Aghaei, Iraj; Vaziri, Zohreh; Sheibani, Vahid; Whalley, Benjamin J; Shabani, Mohammad

    2016-10-01

    Cognitive and motor disturbances are serious consequences of tremor induced by motor disorders. Despite a lack of effective clinical treatment, some potential therapeutic agents have been used to alleviate the cognitive symptoms in the animal models of tremor. In the current study, the effects of WIN55, 212-2 (WIN), a cannabinoid receptor (CBR) agonist, on harmaline-induced motor and cognitive impairments were studied. Adult rats were treated with WIN (0.5mg/kg; i.p.) 15min before harmaline administration (10mg/kg; ip) after which exploratory and anxiety related behaviors, and cognitive function were assessed using open-field behavior and shuttle box tests. Rats that received harmaline only exhibited a markedly reduced number of central square entries when compared to harmaline vehicle-treated controls, whereas those treated with WIN and harmaline showed a significant increase in central square entries, compared to harmaline only treated. The passive avoidance memory impairments observed in harmaline treated rats, was reversed somewhat by administration of WIN. The neuroprotective and anxiolytic effects of WIN demonstrated in the current study can be offered cannabinoid receptor (CBR) agonism as a potential neuroprotective agent in the treatment of patients with tremor that manifest mental dysfunctions. PMID:27317835

  14. Residues accessible in the binding-site crevice of transmembrane helix 6 of the CB2 cannabinoid receptor.

    Science.gov (United States)

    Nebane, Ntsang M; Hurst, Dow P; Carrasquer, Carl A; Qiao, Zhuanhong; Reggio, Patricia H; Song, Zhao-Hui

    2008-12-30

    We have used the substituted-cysteine accessibility method (SCAM) to map the residues in the sixth membrane-spanning segment of the CB2 cannabinoid receptor that contribute to the surface of the water-accessible binding-site crevice. Using a background of the mutant C2.59S which is relatively insensitive to the methanethiosulfonate (MTS) reagents, we mutated to cysteine, one at a time, 34 consecutive residues in TMH6 of the CB2 receptor. These mutant receptors were then expressed in HEK293 cells. By incubating HEK293 cells stably transfected with CB2 receptors with the small, charged, hydrophilic, thiol-specific reagent methanethiosulfonate ethylammonium (MTSEA), [(3)H]CP55940 binding was significantly inhibited for six mutant receptors. All six of the mutants that reacted with MTSEA were protected from the reaction when pretreated with the cannabinoid agonist WIN55212-2, suggesting that MTSEA modification occurred within the binding crevice. Therefore, the side chains of the residues at these reactive loci (V6.51, L6.52, L6.54, M6.55, L6.59, and T6.62) are on the water-accessible surface of the binding-site crevice. These residues are extracellular to the TMH6 CWXP hinge motif. The pattern of accessibility is consistent with a alpha-helical conformation for this segment of TMH6. Molecular modeling studies performed in the context of the CB2 model show that V6.51, L6.52, L6.54, M6.55, L6.59, and T6.62 face into the CB2 binding pocket, further confirming our SCAM results. These results are similar to the accessibility patterns determined by SCAM studies of TMH6 in the opioid and dopamine D2 receptors. PMID:19053233

  15. The role of cannabinoids in modulating emotional and non-emotional memory processes in the hippocampus

    Directory of Open Access Journals (Sweden)

    Irit eAkirav

    2011-06-01

    Full Text Available Cannabinoid agonists generally have a disruptive effect on memory, learning, and operant behavior that is considered to be hippocampus-dependent. Nevertheless, under certain conditions, cannabinoid receptor activation may facilitate neuronal learning processes. For example, CB1 receptors are essential for the extinction of conditioned fear associations, indicating an important role for this receptor in neuronal emotional learning and memory. This review examines the diverse effects of cannabinoids on hippocampal memory and plasticity. It shows how the effects of cannabinoid receptor activation may vary depending on the route of administration, the nature of the task (aversive or not, and whether it involves emotional memory formation (e.g. conditioned fear and extinction learning or non-emotional memory formation (e.g. spatial learning. It also examines the memory stage under investigation (acquisition, consolidation, retrieval, extinction, and the brain areas involved. Differences between the effects of exogenous and endogenous agonists are also discussed. The apparently biphasic effects of cannabinoids on anxiety is noted as this implies that the effects of cannabinoid receptor agonists on hippocampal learning and memory may be attributable to a general modulation of anxiety or stress levels and not to memory per se. The review concludes that cannabinoids have diverse effects on hippocampal memory and plasticity that cannot be categorized simply into an impairing or an enhancing effect. A better understanding of the involvement of cannabinoids in memory processes will help determine whether the benefits of the clinical use of cannabinoids outweigh the risks of possible memory impairments.

  16. Capsaicin and N-arachidonoyl-dopamine (NADA) decrease tension by activating both cannabinoid and vanilloid receptors in fast skeletal muscle fibers of the frog.

    Science.gov (United States)

    Trujillo, Xóchitl; Ortiz-Mesina, Mónica; Uribe, Tannia; Castro, Elena; Montoya-Pérez, Rocío; Urzúa, Zorayda; Feria-Velasco, Alfredo; Huerta, Miguel

    2015-02-01

    Previous studies have indicated that vanilloid receptor (VR1) mRNA is expressed in muscle fibers. In this study, we evaluated the functional effects of VR1 activation. We measured caffeine-induced contractions in bundles of the extensor digitorum longus muscle of Rana pipiens. Isometric tension measurements showed that two VR1 agonists, capsaicin (CAP) and N-arachidonoyl-dopamine (NADA), reduced muscle peak tension to 57 ± 4 % and 71 ± 3% of control, respectively. The effect of CAP was partially blocked by a VR1 blocker, capsazepine (CPZ), but the effect of NADA was not changed by CPZ. Because NADA is able to act on cannabinoid receptors, which are also present in muscle fibers, we tested the cannabinoid antagonist AM281. We found that AM281 antagonized both CAP and NADA effects. AM281 alone reduced peak tension to 80 ± 6 % of control. With both antagonists, the CAP effect was completely blocked, and the NADA effect was partially blocked. These results provide pharmacological evidence of the functional presence of the VR1 receptor in fast skeletal muscle fibers of the frog and suggest that capsaicin and NADA reduce tension by activating both cannabinoid and vanilloid receptors.

  17. [Progress in study on endocannabinoids and cannabinoid receptors in the treatment for neuropathic pain].

    Science.gov (United States)

    Liu, Peng; Zhang, Wei; Zhang, Shaobo; Zhang, Yibao; Wang, Jing

    2016-08-01

    Endocannabinoids and cannabinoid receptors are expressed in various central pain modulation regions. They maintain in dynamic changes in the expression level and distribution under different pathological and physiological conditions. These changes possess advantage as well as disadvantage. Exogenous administration of endocannabinoids exerts analgesic effect in different pain models, which is mainly mediated by the cannabinoid CB1 and CB2 receptors. Inhibition of enzymes for degrading endocannabinoids in different pain models also shows analgesic effect due to the increased local levels of endocannabinoids. PMID:27600019

  18. Exercise reduces adipose tissue via cannabinoid receptor type 1 which is regulated by peroxisome proliferator-activated receptor-delta

    DEFF Research Database (Denmark)

    Yan, Zhen Cheng; Liu, Dao Yan; Zhang, Li Li;

    2007-01-01

    Obesity is one major cardiovascular risk factor. We tested effects of endurance exercise on cannabinoid receptor type 1 (CB1) and peroxisome proliferator-activated receptor-delta (PPAR-delta)-dependent pathways in adipose tissue. Male Wistar rats were randomly assigned to standard laboratory chow...

  19. Cannabinoid receptors in brain: pharmacogenetics, neuropharmacology, neurotoxicology, and potential therapeutic applications.

    Science.gov (United States)

    Onaivi, Emmanuel S

    2009-01-01

    Much progress has been achieved in cannabinoid research. A major breakthrough in marijuana-cannabinoid research has been the discovery of a previously unknown but elaborate endogenous endocannabinoid system (ECS), complete with endocannabinoids and enzymes for their biosynthesis and degradation with genes encoding two distinct cannabinoid (CB1 and CB2) receptors (CBRs) that are activated by endocannabinoids, cannabinoids, and marijuana use. Physical and genetic localization of the CBR genes CNR1 and CNR2 have been mapped to chromosome 6 and 1, respectively. A number of variations in CBR genes have been associated with human disorders including osteoporosis, attention deficit hyperactivity disorder (ADHD), posttraumatic stress disorder (PTSD), drug dependency, obesity, and depression. Other family of lipid receptors including vanilloid (VR1) and lysophosphatidic acid (LPA) receptors appear to be related to the CBRs at the phylogenetic level. The ubiquitous abundance and differential distribution of the ECS in the human body and brain along with the coupling to many signal transduction pathways may explain the effects in most biological system and the myriad behavioral effects associated with smoking marijuana. The neuropharmacological and neuroprotective features of phytocannabinoids and endocannabinoid associated neurogenesis have revealed roles for the use of cannabinoids in neurodegenerative pathologies with less neurotoxicity. The remarkable progress in understanding the biological actions of marijuana and cannabinoids have provided much richer results than previously appreciated cannabinoid genomics and raised a number of critical issues on the molecular mechanisms of cannabinoid induced behavioral and biochemical alterations. These advances will allow specific therapeutic targeting of the different components of the ECS in health and disease. This review focuses on these recent advances in cannabinoid genomics and the surprising new fundamental roles that the

  20. Difference and Influence of Inactive and Active States of Cannabinoid Receptor Subtype CB2: From Conformation to Drug Discovery.

    Science.gov (United States)

    Hu, Jianping; Feng, Zhiwei; Ma, Shifan; Zhang, Yu; Tong, Qin; Alqarni, Mohammed Hamed; Gou, Xiaojun; Xie, Xiang-Qun

    2016-06-27

    Cannabinoid receptor 2 (CB2), a G protein-coupled receptor (GPCR), is a promising target for the treatment of neuropathic pain, osteoporosis, immune system, cancer, and drug abuse. The lack of an experimental three-dimensional CB2 structure has hindered not only the development of studies of conformational differences between the inactive and active CB2 but also the rational discovery of novel functional compounds targeting CB2. In this work, we constructed models of both inactive and active CB2 by homology modeling. Then we conducted two comparative 100 ns molecular dynamics (MD) simulations on the two systems-the active CB2 bound with both the agonist and G protein and the inactive CB2 bound with inverse agonist-to analyze the conformational difference of CB2 proteins and the key residues involved in molecular recognition. Our results showed that the inactive CB2 and the inverse agonist remained stable during the MD simulation. However, during the MD simulations, we observed dynamical details about the breakdown of the "ionic lock" between R131(3.50) and D240(6.30) as well as the outward/inward movements of transmembrane domains of the active CB2 that bind with G proteins and agonist (TM5, TM6, and TM7). All of these results are congruent with the experimental data and recent reports. Moreover, our results indicate that W258(6.48) in TM6 and residues in TM4 (V164(4.56)-L169(4.61)) contribute greatly to the binding of the agonist on the basis of the binding energy decomposition, while residues S180-F183 in extracellular loop 2 (ECL2) may be of importance in recognition of the inverse agonist. Furthermore, pharmacophore modeling and virtual screening were carried out for the inactive and active CB2 models in parallel. Among all 10 hits, two compounds exhibited novel scaffolds and can be used as novel chemical probes for future studies of CB2. Importantly, our studies show that the hits obtained from the inactive CB2 model mainly act as inverse agonist(s) or neutral

  1. Difference and Influence of Inactive and Active States of Cannabinoid Receptor Subtype CB2: From Conformation to Drug Discovery.

    Science.gov (United States)

    Hu, Jianping; Feng, Zhiwei; Ma, Shifan; Zhang, Yu; Tong, Qin; Alqarni, Mohammed Hamed; Gou, Xiaojun; Xie, Xiang-Qun

    2016-06-27

    Cannabinoid receptor 2 (CB2), a G protein-coupled receptor (GPCR), is a promising target for the treatment of neuropathic pain, osteoporosis, immune system, cancer, and drug abuse. The lack of an experimental three-dimensional CB2 structure has hindered not only the development of studies of conformational differences between the inactive and active CB2 but also the rational discovery of novel functional compounds targeting CB2. In this work, we constructed models of both inactive and active CB2 by homology modeling. Then we conducted two comparative 100 ns molecular dynamics (MD) simulations on the two systems-the active CB2 bound with both the agonist and G protein and the inactive CB2 bound with inverse agonist-to analyze the conformational difference of CB2 proteins and the key residues involved in molecular recognition. Our results showed that the inactive CB2 and the inverse agonist remained stable during the MD simulation. However, during the MD simulations, we observed dynamical details about the breakdown of the "ionic lock" between R131(3.50) and D240(6.30) as well as the outward/inward movements of transmembrane domains of the active CB2 that bind with G proteins and agonist (TM5, TM6, and TM7). All of these results are congruent with the experimental data and recent reports. Moreover, our results indicate that W258(6.48) in TM6 and residues in TM4 (V164(4.56)-L169(4.61)) contribute greatly to the binding of the agonist on the basis of the binding energy decomposition, while residues S180-F183 in extracellular loop 2 (ECL2) may be of importance in recognition of the inverse agonist. Furthermore, pharmacophore modeling and virtual screening were carried out for the inactive and active CB2 models in parallel. Among all 10 hits, two compounds exhibited novel scaffolds and can be used as novel chemical probes for future studies of CB2. Importantly, our studies show that the hits obtained from the inactive CB2 model mainly act as inverse agonist(s) or neutral

  2. Maternal deprivation and adolescent cannabinoid exposure impact hippocampal astrocytes, CB1 receptors and brain-derived neurotrophic factor in a sexually dimorphic fashion.

    Science.gov (United States)

    López-Gallardo, M; López-Rodríguez, A B; Llorente-Berzal, Á; Rotllant, D; Mackie, K; Armario, A; Nadal, R; Viveros, M-P

    2012-03-01

    We have recently reported that early maternal deprivation (MD) for 24 h [postnatal day (PND) 9-10] and/or an adolescent chronic treatment with the cannabinoid agonist CP-55,940 (CP) [0.4 mg/kg, PND 28-42] in Wistar rats induced, in adulthood, diverse sex-dependent long-term behavioral and physiological modifications. Here we show the results obtained from investigating the immunohistochemical analysis of CB1 cannabinoid receptors, glial fibrillary acidic protein (GFAP) positive (+) cells and brain-derived neurotrophic factor (BDNF) expression in the hippocampus of the same animals. MD induced, in males, a significant increase in the number of GFAP+ cells in CA1 and CA3 areas and in the polymorphic layer of the dentate gyrus (DG), an effect that was attenuated by CP in the two latter regions. Adolescent cannabinoid exposure induced, in control non-deprived males, a significant increase in the number of GFAP+ cells in the polymorphic layer of the DG. MD induced a decrease in CB1 expression in both sexes, and this effect was reversed in males by the cannabinoid treatment. In turn, the drug "per se" induced, in males, a general decrease in CB1 immunoreactivity, and the opposite effect was observed in females. Cannabinoid exposure tended to reduce BDNF expression in CA1 and CA3 of females, whereas MD counteracted this trend and induced an increase of BDNF in females. As a whole, the present results show sex-dependent long-term effects of both MD and juvenile cannabinoid exposure as well as functional interactions between the two treatments.

  3. Pharmacological activation of cannabinoid 2 receptor attenuates inflammation, fibrogenesis, and promotes re-epithelialization during skin wound healing.

    Science.gov (United States)

    Wang, Lin-Lin; Zhao, Rui; Li, Jiao-Yong; Li, Shan-Shan; Liu, Min; Wang, Meng; Zhang, Meng-Zhou; Dong, Wen-Wen; Jiang, Shu-Kun; Zhang, Miao; Tian, Zhi-Ling; Liu, Chang-Sheng; Guan, Da-Wei

    2016-09-01

    Previous studies showed that cannabinoid 2 (CB2) receptor is expressed in multiple effector cells during skin wound healing. Meanwhile, its functional involvement in inflammation, fibrosis, and cell proliferation in other organs and skin diseases implied CB2 receptor might also regulate skin wound healing. To verify this hypothesis, mice excisional wounds were created and treated with highly selective CB2 receptor agonist GP1a (1-(2,4-dichlorophenyl)-6-methyl- N-piperidin-1-yl-4H-indeno[1,2-c]pyrazole-3-carboxamide) and antagonist AM630 ([6-iodo-2- methyl-1-(2-morpholin-4-ylethyl)indol-3-yl]-(4-methoxyphenyl)methanone) respectively. The inflammatory infiltration, cytokine expression, fibrogenesis, and wound re-epithelialization were analyzed. After CB2 receptor activation, neutrophil and macrophage infiltrations were reduced, and expressions of monocyte chemotactic protein (MCP)-1, stromal cell-derived factor (SDF)-1, Interleukin (IL)-6, IL-1β, tumor necrosis factor (TNF)-α, transforming growth factor (TGF)-β1 and vascular endothelial growth factor (VEGF)-A were decreased. Keratinocyte proliferation and migration were enhanced. Wound re-epithelialization was accelerated. Fibroblast accumulation and fibroblast-to-myofibroblast transformation were attenuated, and expression of pro-collagen I was decreased. Furthermore, HaCaT cells in vitro were treated with GP1a or AM630, which revealed that CB2 receptor activation promoted keratinocyte migration by inducing the epithelial to mesenchymal transition. These results, taken together, indicate that activating CB2 receptor could ameliorate wound healing by reducing inflammation, accelerating re-epithelialization, and attenuating scar formation. Thus, CB2 receptor agonist might be a novel perspective for skin wound therapy. PMID:27268717

  4. Systemic cancer immunotherapy with Toll-like receptor 7 agonists

    Science.gov (United States)

    Hotz, Christian; Bourquin, Carole

    2012-01-01

    Toll-like receptor (TLR) 7 agonists represent a promising strategy for the immunotherapy of cancer. We have recently investigated the influence of TLR tolerance on the efficacy of systemic tumor treatment with TLR7 ligands. We propose that considering the kinetics of receptor sensitivity highly improves the outcome of cancer immunotherapy. PMID:22720251

  5. (+)-Cannabidiol analogues which bind cannabinoid receptors but exert peripheral activity only.

    Science.gov (United States)

    Fride, Ester; Feigin, Cfir; Ponde, Datta E; Breuer, Aviva; Hanus, Lumír; Arshavsky, Nina; Mechoulam, Raphael

    2004-12-15

    Delta9-Tetrahydrocannabinol (Delta9-THC) and (-)-cannabidiol are major constituents of the Cannabis sativa plant with different pharmacological profiles: (-)-Delta9-tetrahydrocannabinol, but not (-)-cannabidiol, activates cannabinoid CB1 and CB2 receptors and induces psychoactive and peripheral effects. We have tested a series of (+)-cannabidiol derivatives, namely, (+)-cannabidiol-DMH (DMH-1,1-dimethylheptyl-), (+)-7-OH-cannabidiol-DMH, (+)-7-OH- cannabidiol, (+)-7-COOH- cannabidiol and (+)-7-COOH-cannabidiol-DMH, for central and peripheral (intestinal, antiinflammatory and peripheral pain) effects in mice. Although all (+)-cannabidiols bind to cannabinoid CB1 and CB2 receptors, only (+)-7-OH-cannabidiol-DMH was centrally active, while all (+)-cannabidiol analogues completely arrested defecation. The effects of (+)-cannabidiol-DMH and (+)-7-OH-cannabidiol-DMH were partially antagonized by the cannabinoid CB1 receptor antagonist N-(piperidiny-1-yl)-5-(4-chlorophenyl)-1-(2,4-dichlorophenyl)-4-methyl-1H-pyrazole-3-carboxamide (SR141716), but not by the cannabinoid CB2 receptor antagonist N-[-(1S)-endo-1,3,3-trimethil bicyclo [2.2.1] heptan-2-yl-5-(4-chloro-3-methylphenyl)-1-(4-methylbenzyl)-pyrazole-3-carboxamide (SR144528), and had no effect on CB1(-/-) receptor knockout mice. (+)-Cannabidiol-DMH inhibited the peripheral pain response and arachidonic-acid-induced inflammation of the ear. We conclude that centrally inactive (+)-cannabidiol analogues should be further developed as antidiarrheal, antiinflammatory and analgesic drugs for gastrointestinal and other peripheral conditions. PMID:15588739

  6. Neuroprotective effects of the cannabinoid agonist HU210 on retinal degeneration.

    Science.gov (United States)

    Lax, Pedro; Esquiva, Gema; Altavilla, Cesare; Cuenca, Nicolás

    2014-03-01

    Cannabinoids have been demonstrated to exert neuroprotective effects on different types of neuronal insults. Here we have addressed the therapeutic potential of the synthetic cannabinoid HU210 on photoreceptor degeneration, synaptic connectivity and functional activity of the retina in the transgenic P23H rat, an animal model for autosomal dominant retinitis pigmentosa (RP). In P23H rats administered with HU210 (100 μg/kg, i.p.) from P24 to P90, ERG recordings showed an amelioration of vision loss, as compared to vehicle-administered animals. Under scotopic conditions, the maximum a-wave amplitudes recorded at P60 and P90 were higher in HU210-treated animals, as compared to the values obtained in untreated animals. The scotopic b-waves were significantly higher in treated animals than in untreated rats at P30, P60 and P90. This attenuation of visual deterioration correlated with a delay in photoreceptor degeneration and the preservation of retinal cytoarchitecture. HU210-treated animals had 40% more photoreceptors than untreated animals. Presynaptic and postsynaptic elements, as well as the synaptic contacts between photoreceptors and bipolar or horizontal cells, were also preserved in HU210-treated P23H rats. These results indicate that HU210 preserves cone and rod structure and function, together with their contacts with postsynaptic neurons, in P23H rats. These data suggest that cannabinoids are potentially useful to delay retinal degeneration in RP patients.

  7. Minocycline Attenuates Neonatal Germinal-Matrix-Hemorrhage-Induced Neuroinflammation and Brain Edema by Activating Cannabinoid Receptor 2.

    Science.gov (United States)

    Tang, Jun; Chen, Qianwei; Guo, Jing; Yang, Liming; Tao, Yihao; Li, Lin; Miao, Hongping; Feng, Hua; Chen, Zhi; Zhu, Gang

    2016-04-01

    Germinal matrix hemorrhage (GMH) is the most common neurological disease of premature newborns leading to detrimental neurological sequelae. Minocycline has been reported to play a key role in neurological inflammatory diseases by controlling some mechanisms that involve cannabinoid receptor 2 (CB2R). The current study investigated whether minocycline reduces neuroinflammation and protects the brain from injury in a rat model of collagenase-induced GMH by regulating CB2R activity. To test this hypothesis, the effects of minocycline and a CB2R antagonist (AM630) were evaluated in male rat pups that were post-natal day 7 (P7) after GMH. We found that minocycline can lead to increased CB2R mRNA expression and protein expression in microglia. Minocycline significantly reduced GMH-induced brain edema, microglial activation, and lateral ventricular volume. Additionally, minocycline enhanced cortical thickness after injury. All of these neuroprotective effects of minocycline were prevented by AM630. A cannabinoid CB2 agonist (JWH133) was used to strengthen the hypothesis, which showed the identical neuroprotective effects of minocycline. Our study demonstrates, for the first time, that minocycline attenuates neuroinflammation and brain injury in a rat model of GMH, and activation of CBR2 was partially involved in these processes. PMID:25833102

  8. Possible Therapeutic Doses of Cannabinoid Type 1 Receptor Antagonist Reverses Key Alterations in Fragile X Syndrome Mouse Model.

    Science.gov (United States)

    Gomis-González, Maria; Matute, Carlos; Maldonado, Rafael; Mato, Susana; Ozaita, Andrés

    2016-01-01

    Fragile X syndrome (FXS) is the most common monogenetic cause of intellectual disability. The cognitive deficits in the mouse model for this disorder, the Fragile X Mental Retardation 1 (Fmr1) knockout (KO) mouse, have been restored by different pharmacological approaches, among those the blockade of cannabinoid type 1 (CB1) receptor. In this regard, our previous study showed that the CB1 receptor antagonist/inverse agonist rimonabant normalized a number of core features in the Fmr1 knockout mouse. Rimonabant was commercialized at high doses for its anti-obesity properties, and withdrawn from the market on the bases of mood-related adverse effects. In this study we show, by using electrophysiological approaches, that low dosages of rimonabant (0.1 mg/kg) manage to normalize metabotropic glutamate receptor dependent long-term depression (mGluR-LTD). In addition, low doses of rimonabant (from 0.01 mg/kg) equally normalized the cognitive deficit in the mouse model of FXS. These doses of rimonabant were from 30 to 300 times lower than those required to reduce body weight in rodents and to presumably produce adverse effects in humans. Furthermore, NESS0327, a CB1 receptor neutral antagonist, was also effective in preventing the novel object-recognition memory deficit in Fmr1 KO mice. These data further support targeting CB1 receptors as a relevant therapy for FXS. PMID:27589806

  9. Possible Therapeutic Doses of Cannabinoid Type 1 Receptor Antagonist Reverses Key Alterations in Fragile X Syndrome Mouse Model

    Science.gov (United States)

    Gomis-González, Maria; Busquets-Garcia, Arnau; Matute, Carlos; Maldonado, Rafael; Mato, Susana; Ozaita, Andrés

    2016-01-01

    Fragile X syndrome (FXS) is the most common monogenetic cause of intellectual disability. The cognitive deficits in the mouse model for this disorder, the Fragile X Mental Retardation 1 (Fmr1) knockout (KO) mouse, have been restored by different pharmacological approaches, among those the blockade of cannabinoid type 1 (CB1) receptor. In this regard, our previous study showed that the CB1 receptor antagonist/inverse agonist rimonabant normalized a number of core features in the Fmr1 knockout mouse. Rimonabant was commercialized at high doses for its anti-obesity properties, and withdrawn from the market on the bases of mood-related adverse effects. In this study we show, by using electrophysiological approaches, that low dosages of rimonabant (0.1 mg/kg) manage to normalize metabotropic glutamate receptor dependent long-term depression (mGluR-LTD). In addition, low doses of rimonabant (from 0.01 mg/kg) equally normalized the cognitive deficit in the mouse model of FXS. These doses of rimonabant were from 30 to 300 times lower than those required to reduce body weight in rodents and to presumably produce adverse effects in humans. Furthermore, NESS0327, a CB1 receptor neutral antagonist, was also effective in preventing the novel object-recognition memory deficit in Fmr1 KO mice. These data further support targeting CB1 receptors as a relevant therapy for FXS. PMID:27589806

  10. Loss of cannabinoid receptor CB1 induces preterm birth.

    Directory of Open Access Journals (Sweden)

    Haibin Wang

    Full Text Available BACKGROUND: Preterm birth accounting approximate 10% of pregnancies in women is a tremendous social, clinical and economic burden. However, its underlying causes remain largely unknown. Emerging evidence suggests that endocannabinoid signaling via cannabinoid receptor CB1 play critical roles in multiple early pregnancy events in both animals and humans. Since our previous studies demonstrated that loss of CB1 defers the normal implantation window in mice, we surmised that CB1 deficiency would influence parturition events. METHODS AND FINDINGS: Exploiting mouse models with targeted deletion of Cnr1, Cnr2 and Ptgs1 encoding CB1, CB2 and cyclooxygenase-1, respectively, we examined consequences of CB1 or CB2 silencing on the onset of parturition. We observed that genetic or pharmacological inactivation of CB1, but not CB2, induced preterm labor in mice. Radioimmunoassay analysis of circulating levels of ovarian steroid hormones revealed that premature birth resulting from CB1 inactivation is correlated with altered progesterone/estrogen ratios prior to parturition. More strikingly, the phenotypic defects of prolonged pregnancy length and parturition failure in mice missing Ptgs1 were corrected by introducing CB1 deficiency into Ptgs1 null mice. In addition, loss of CB1 resulted in aberrant secretions of corticotrophin-releasing hormone and corticosterone during late gestation. The pathophysiological significance of this altered corticotrophin-releasing hormone-driven endocrine activity in the absence of CB1 was evident from our subsequent findings that a selective corticotrophin-releasing hormone antagonist was able to restore the normal parturition timing in Cnr1 deficient mice. In contrast, wild-type females receiving excessive levels of corticosterone induced preterm birth. CONCLUSIONS: CB1 deficiency altering normal progesterone and estrogen levels induces preterm birth in mice. This defect is independent of prostaglandins produced by

  11. Inhibition of leukocyte function and interleukin-2 gene expression by 2-methylarachidonyl-(2'-fluoroethyl)amide, a stable congener of the endogenous cannabinoid receptor ligand anandamide

    International Nuclear Information System (INIS)

    Arachidonylethanolamide (anandamide, AEA) has been identified as an endogenous ligand for cannabinoid receptors CB1 and CB2. Characterization of the direct cannabimimetic actions of anandamide has been hampered by its short duration of action and rapid degradation in in vivo and in vitro systems to arachidonic acid, a precursor in the biosynthesis of a broad range of biologically active molecules. In the present studies, we utilized 2-methylarachidonyl-(2'-fluoroethyl)amide (F-Me-AEA), an analog of anandamide resistant to enzymatic degradation, to determine whether F-Me-AEA modulated T cell function similar to that of plant-derived cannabinoids. Indeed, F-Me-AEA at low micromolar concentrations exhibited a marked inhibition of phorbol ester plus calcium ionophore (PMA/Io)-induced IL-2 protein secretion and steady state mRNA expression. Likewise, a modest suppression of the mixed lymphocyte response was observed in the presence of F-Me-AEA indicating an alteration in T cell responsiveness to allogeneic MHC class II antigens. F-Me-AEA was also found to modestly inhibit forskolin-stimulated adenylate cyclase activity in thymocytes and splenocytes, a hallmark of cannabinoid receptor agonists. Further characterization of the influence of F-Me-AEA on the cAMP signaling cascade revealed an inhibition of CREB-1/ATF-1 phosphorylation and subsequently, an inhibition of CRE DNA binding activity. Characterization of nuclear binding proteins further revealed that NF-AT and, to a lesser extent, NF-κB DNA binding activities were also suppressed. These studies demonstrate that F-Me-AEA modulates T cell function in a similar manner to plant-derived and endogenous cannabinoids and therefore can be utilized as an amidase- and hydrolysis-resistant endogenous cannabinoid

  12. Evaluation of the In Vivo and Ex Vivo Binding of Novel BC1 Cannabinoid Receptor Radiotracers

    Energy Technology Data Exchange (ETDEWEB)

    Miller, A.; Gatley, J.; Gifford, A.

    2002-01-01

    The primary active ingredient of marijuana, 9-tetrahydrocannabinol, exerts its psychoactive effects by binding to cannabinoid CB1 receptors. These receptors are found throughout the brain with high concentrations in the hippocampus and cerebellum. The current study was conducted to evaluate the binding of a newly developed putative cannabinoid antagonist, AM630, and a classical cannabinoid 8-tetrahydrocannabinol as potential PET and/or SPECT imaging agents for brain CB1 receptors. For both of these ligands in vivo and ex vivo studies in mice were conducted. AM630 showed good overall brain uptake (as measure by %IA/g) and a moderately rapid clearance from the brain with a half-clearance time of approximately 30 minutes. However, AM630 did not show selective binding to CB1 cannabinoid receptors. Ex vivo autoradiography supported the lack of selective binding seen in the in vivo study. Similar to AM630, 8-tetrahydrocanibol also failed to show selective binding to CB1 receptor rich brain areas. The 8-tetrahydrocanibol showed moderate overall brain uptake and relatively slow brain clearance as compared to AM630. Further studies were done with AM2233, a cannabinoid ligand with a similar structure as AM630. These studies were done to develop an ex vivo binding assay to quantify the displacement of [131I]AM2233 binding by other ligands in Swiss-Webster and CB1 receptor knockout mice. By developing this assay we hoped to determine the identity of an unknown binding site for AM2233 present in the hippocampus of CB1 knockout mice. Using an approach based on incubation of brain slices prepared from mice given intravenous [131I]AM2233 in either the presence or absence of AM2233 (unlabelled) it was possible to demonstrate a significant AM2233-displacable binding in the Swiss-Webster mice. Future studies will determine if this assay is appropriate for identifying the unknown binding site for AM2233 in the CB1 knockout mice.

  13. CB1 Cannabinoid Receptors Modulate Kinase and Phosphatase Activity during Extinction of Conditioned Fear in Mice

    Science.gov (United States)

    Kamprath, Kornelia; Hermann, Heike; Lutz, Beat; Marsicano, Giovanni; Cannich, Astrid; Wotjak, Carsten T.

    2004-01-01

    Cannabinoid receptors type 1 (CB1) play a central role in both short-term and long-term extinction of auditory-cued fear memory. The molecular mechanisms underlying this function remain to be clarified. Several studies indicated extracellular signal-regulated kinases (ERKs), the phosphatidylinositol 3-kinase with its downstream effector AKT, and…

  14. Deficits in Sensory-Specific Devaluation Task Performance Following Genetic Deletions of Cannabinoid (CB1) Receptor

    Science.gov (United States)

    Crombag, Hans S.; Johnson, Alexander W.; Zimmer, Anne M.; Zimmer, Andreas; Holland, Peter C.

    2010-01-01

    Cannabinoid CB1 receptor is abundantly expressed throughout the CNS and is implicated in numerous physiological and behavioral functions, including appetite and feeding. In the present study, wild-type and CB1 heterozygous and homozygous knockout mice were tested on an instrumental outcome-selective devaluation task to assess changes in acquired…

  15. Motivational effects of cannabinoids are mediated by ??-opioid and k-opioid receptor

    OpenAIRE

    Ghozland, Sandy; Matthes, Hans W.D.; Simonin, Frederic; Filliol, Dominique; Kieffer, Brigitte L.; Maldonado, Rafael

    2002-01-01

    Repeated THC administration produces motivational and somatic adaptive changes leading to dependence in rodents. To investigate the molecular basis for cannabinoid dependence and its possible relationship with the endogenous opioid system, we explored ??9-tetrahydrocannabinol (THC) activity in mice lacking ??-, ??- or ??-opioid receptor genes. Acute THCinduced hypothermia, antinociception, and ypolocomotion remained unaffected in these mice, whereas THC tolerance and withdrawal...

  16. Effect of the cannabinoid receptor-1 antagonist rimonabant on lipolysis in rats

    DEFF Research Database (Denmark)

    Mølhøj, Signe; Hansen, Harald S; Schweiger, Martina;

    2010-01-01

    The cannabinoid receptor 1 antagonist, rimonabant, reduces food intake and body weight, but contradictory findings have been reported as to whether the weight-reducing effect is fully accounted for by the reduced food intake or if rimonabant also mediates a lipolytic effect. In the present study...

  17. Principles of agonist recognition in Cys-loop receptors

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    Timothy eLynagh

    2014-04-01

    Full Text Available Cys-loop receptors are ligand-gated ion channels that are activated by a structurally diverse array of neurotransmitters, including acetylcholine, serotonin, glycine and GABA. After the term chemoreceptor emerged over 100 years ago, there was some wait until affinity labeling, molecular cloning, functional studies and X-ray crystallography experiments identified the extracellular interface of adjacent subunits as the principal site of agonist binding. The question of how subtle differences at and around agonist-binding sites of different Cys-loop receptors can accommodate transmitters as chemically diverse as glycine and serotonin has been subject to intense research over the last three decades. This review outlines the functional diversity and current structural understanding of agonist-binding sites, including those of invertebrate Cys-loop receptors. Together, this provides a framework to understand the atomic determinants involved in how these valuable therapeutic targets recognize and bind their ligands.

  18. Subtype selective kainic acid receptor agonists

    DEFF Research Database (Denmark)

    Bunch, Lennart; Krogsgaard-Larsen, Povl

    2009-01-01

    (S)-Glutamic acid (Glu) is the major excitatory neurotransmitter in the mammalian central nervous system, activating the plethora of glutamate receptors (GluRs). In broad lines, the GluRs are divided into two major classes: the ionotropic Glu receptors (iGluRs) and the metabotropic Glu receptors ...

  19. Cannabinoid receptor type-1: breaking the dogmas [version 1; referees: 3 approved

    Directory of Open Access Journals (Sweden)

    Arnau Busquets Garcia

    2016-05-01

    Full Text Available The endocannabinoid system (ECS is abundantly expressed in the brain. This system regulates a plethora of physiological functions and is composed of cannabinoid receptors, their endogenous ligands (endocannabinoids, and the enzymes involved in the metabolism of endocannabinoids. In this review, we highlight the new advances in cannabinoid signaling, focusing on a key component of the ECS, the type-1 cannabinoid receptor (CB1. In recent years, the development of new imaging and molecular tools has demonstrated that this receptor can be distributed in many cell types (e.g., neuronal or glial cells and intracellular compartments (e.g., mitochondria. Interestingly, cellular and molecular effects are differentially mediated by CB1 receptors according to their specific localization (e.g., glutamatergic or GABAergic neurons. Moreover, this receptor is expressed in the periphery, where it can modulate periphery-brain connections. Finally, the better understanding of the CB1 receptor structure led researchers to propose interesting and new allosteric modulators. Thus, the advances and the new directions of the CB1 receptor field will provide new insights and better approaches to profit from its interesting therapeutic profile.

  20. Genetic variations in the human cannabinoid receptor gene are associated with happiness.

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    Masahiro Matsunaga

    Full Text Available Happiness has been viewed as a temporary emotional state (e.g., pleasure and a relatively stable state of being happy (subjective happiness level. As previous studies demonstrated that individuals with high subjective happiness level rated their current affective states more positively when they experience positive events, these two aspects of happiness are interrelated. According to a recent neuroimaging study, the cytosine to thymine single-nucleotide polymorphism of the human cannabinoid receptor 1 gene is associated with sensitivity to positive emotional stimuli. Thus, we hypothesized that our genetic traits, such as the human cannabinoid receptor 1 genotypes, are closely related to the two aspects of happiness. In Experiment 1, 198 healthy volunteers were used to compare the subjective happiness level between cytosine allele carriers and thymine-thymine carriers of the human cannabinoid receptor 1 gene. In Experiment 2, we used positron emission tomography with 20 healthy participants to compare the brain responses to positive emotional stimuli of cytosine allele carriers to that of thymine-thymine carriers. Compared to thymine-thymine carriers, cytosine allele carriers have a higher subjective happiness level. Regression analysis indicated that the cytosine allele is significantly associated with subjective happiness level. The positive mood after watching a positive film was significantly higher for the cytosine allele carriers compared to the thymine-thymine carriers. Positive emotion-related brain region such as the medial prefrontal cortex was significantly activated when the cytosine allele carriers watched the positive film compared to the thymine-thymine carriers. Thus, the human cannabinoid receptor 1 genotypes are closely related to two aspects of happiness. Compared to thymine-thymine carriers, the cytosine allele carriers of the human cannabinoid receptor 1 gene, who are sensitive to positive emotional stimuli, exhibited greater

  1. Genetic variations in the human cannabinoid receptor gene are associated with happiness.

    Science.gov (United States)

    Matsunaga, Masahiro; Isowa, Tokiko; Yamakawa, Kaori; Fukuyama, Seisuke; Shinoda, Jun; Yamada, Jitsuhiro; Ohira, Hideki

    2014-01-01

    Happiness has been viewed as a temporary emotional state (e.g., pleasure) and a relatively stable state of being happy (subjective happiness level). As previous studies demonstrated that individuals with high subjective happiness level rated their current affective states more positively when they experience positive events, these two aspects of happiness are interrelated. According to a recent neuroimaging study, the cytosine to thymine single-nucleotide polymorphism of the human cannabinoid receptor 1 gene is associated with sensitivity to positive emotional stimuli. Thus, we hypothesized that our genetic traits, such as the human cannabinoid receptor 1 genotypes, are closely related to the two aspects of happiness. In Experiment 1, 198 healthy volunteers were used to compare the subjective happiness level between cytosine allele carriers and thymine-thymine carriers of the human cannabinoid receptor 1 gene. In Experiment 2, we used positron emission tomography with 20 healthy participants to compare the brain responses to positive emotional stimuli of cytosine allele carriers to that of thymine-thymine carriers. Compared to thymine-thymine carriers, cytosine allele carriers have a higher subjective happiness level. Regression analysis indicated that the cytosine allele is significantly associated with subjective happiness level. The positive mood after watching a positive film was significantly higher for the cytosine allele carriers compared to the thymine-thymine carriers. Positive emotion-related brain region such as the medial prefrontal cortex was significantly activated when the cytosine allele carriers watched the positive film compared to the thymine-thymine carriers. Thus, the human cannabinoid receptor 1 genotypes are closely related to two aspects of happiness. Compared to thymine-thymine carriers, the cytosine allele carriers of the human cannabinoid receptor 1 gene, who are sensitive to positive emotional stimuli, exhibited greater magnitude

  2. Cannabinoid CB2 receptors regulate central sensitization and pain responses associated with osteoarthritis of the knee joint.

    Science.gov (United States)

    Burston, James J; Sagar, Devi Rani; Shao, Pin; Bai, Mingfeng; King, Emma; Brailsford, Louis; Turner, Jenna M; Hathway, Gareth J; Bennett, Andrew J; Walsh, David A; Kendall, David A; Lichtman, Aron; Chapman, Victoria

    2013-01-01

    Osteoarthritis (OA) of the joint is a prevalent disease accompanied by chronic, debilitating pain. Recent clinical evidence has demonstrated that central sensitization contributes to OA pain. An improved understanding of how OA joint pathology impacts upon the central processing of pain is crucial for the identification of novel analgesic targets/new therapeutic strategies. Inhibitory cannabinoid 2 (CB2) receptors attenuate peripheral immune cell function and modulate central neuro-immune responses in models of neurodegeneration. Systemic administration of the CB2 receptor agonist JWH133 attenuated OA-induced pain behaviour, and the changes in circulating pro- and anti-inflammatory cytokines exhibited in this model. Electrophysiological studies revealed that spinal administration of JWH133 inhibited noxious-evoked responses of spinal neurones in the model of OA pain, but not in control rats, indicating a novel spinal role of this target. We further demonstrate dynamic changes in spinal CB2 receptor mRNA and protein expression in an OA pain model. The expression of CB2 receptor protein by both neurones and microglia in the spinal cord was significantly increased in the model of OA. Hallmarks of central sensitization, significant spinal astrogliosis and increases in activity of metalloproteases MMP-2 and MMP-9 in the spinal cord were evident in the model of OA pain. Systemic administration of JWH133 attenuated these markers of central sensitization, providing a neurobiological basis for analgesic effects of the CB2 receptor in this model of OA pain. Analysis of human spinal cord revealed a negative correlation between spinal cord CB2 receptor mRNA and macroscopic knee chondropathy. These data provide new clinically relevant evidence that joint damage and spinal CB2 receptor expression are correlated combined with converging pre-clinical evidence that activation of CB2 receptors inhibits central sensitization and its contribution to the manifestation of chronic OA

  3. Cannabinoid CB2 receptors regulate central sensitization and pain responses associated with osteoarthritis of the knee joint.

    Directory of Open Access Journals (Sweden)

    James J Burston

    Full Text Available Osteoarthritis (OA of the joint is a prevalent disease accompanied by chronic, debilitating pain. Recent clinical evidence has demonstrated that central sensitization contributes to OA pain. An improved understanding of how OA joint pathology impacts upon the central processing of pain is crucial for the identification of novel analgesic targets/new therapeutic strategies. Inhibitory cannabinoid 2 (CB2 receptors attenuate peripheral immune cell function and modulate central neuro-immune responses in models of neurodegeneration. Systemic administration of the CB2 receptor agonist JWH133 attenuated OA-induced pain behaviour, and the changes in circulating pro- and anti-inflammatory cytokines exhibited in this model. Electrophysiological studies revealed that spinal administration of JWH133 inhibited noxious-evoked responses of spinal neurones in the model of OA pain, but not in control rats, indicating a novel spinal role of this target. We further demonstrate dynamic changes in spinal CB2 receptor mRNA and protein expression in an OA pain model. The expression of CB2 receptor protein by both neurones and microglia in the spinal cord was significantly increased in the model of OA. Hallmarks of central sensitization, significant spinal astrogliosis and increases in activity of metalloproteases MMP-2 and MMP-9 in the spinal cord were evident in the model of OA pain. Systemic administration of JWH133 attenuated these markers of central sensitization, providing a neurobiological basis for analgesic effects of the CB2 receptor in this model of OA pain. Analysis of human spinal cord revealed a negative correlation between spinal cord CB2 receptor mRNA and macroscopic knee chondropathy. These data provide new clinically relevant evidence that joint damage and spinal CB2 receptor expression are correlated combined with converging pre-clinical evidence that activation of CB2 receptors inhibits central sensitization and its contribution to the manifestation

  4. Behavioral phenotypes of mice lacking cannabinoid CB1 receptors in different neuronal subpopulations

    OpenAIRE

    Bernardes Terzian, Ana Luisa

    2014-01-01

    Abnormalities in social behavior are found in almost all psychiatric disorders, such as anxiety, depression, autism and schizophrenia. Thus, comprehension of the neurobiological basis of social interaction is important to better understand numerous pathologies and improve treatments. Several evidences suggest that an alteration of cannabinoid CB1 receptor function could be involved in the pathophysiology of such disorders. However, the role of CB1 receptor is still unclear and its localizatio...

  5. Adenosine A1 receptor agonists inhibit trigeminovascular nociceptive transmission

    DEFF Research Database (Denmark)

    Goadsby, P J; Hoskin, K L; Storer, R J;

    2002-01-01

    There is a considerable literature to suggest that adenosine A1 receptor agonists may have anti-nociceptive effects, and we sought to explore the role of adenosine A1 receptors in a model of trigeminovascular nociceptive transmission. Cats were anaesthetized (alpha-chloralose 60 mg/kg, intraperit......There is a considerable literature to suggest that adenosine A1 receptor agonists may have anti-nociceptive effects, and we sought to explore the role of adenosine A1 receptors in a model of trigeminovascular nociceptive transmission. Cats were anaesthetized (alpha-chloralose 60 mg...... from the external jugular vein to determine levels of calcitonin gene-related peptide (CGRP) release before and after drug administration. Intravenous administration of the highly selective adenosine A1 receptor agonist, GR79236 (3-100 microg/kg) had a dose-dependent inhibitory effect on SSS...... 33 +/- 2 pmol/l (n = 6) to 64 +/- 3 pmol/l, an effect substantially reduced by pre-treatment with GR79236 (30 microg/kg; P agonist, GR190178 (30-1000 microg/kg i.v.), also inhibited SSS-evoked neuronal activity in a dose-dependent fashion...

  6. The effect of spinally administered WIN 55,212-2, a cannabinoid agonist, on thermal pain sensitivity in diabetic rats

    Directory of Open Access Journals (Sweden)

    Samane Jahanabadi

    2016-04-01

    Conclusion: These data show that cannabinoids have potent antinociceptive effects through direct actions in the spinal dorsal horn of nociceptive pathway. This suggests that intrathecally administered cannabinoids may offer hopeful strategies for the treatment of diabetic neuropathic pain.

  7. Toll-like receptor 2 agonists inhibit human fibrocyte differentiation

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    Maharjan Anu S

    2010-11-01

    Full Text Available Abstract Background In healing wounds, some monocytes enter the wound and differentiate into fibroblast-like cells called fibrocytes. Since Toll-like receptors (TLRs are present on monocytes, and pathogens that can infect a wound have and/or release TLR agonists, we examined whether TLR agonists affect fibrocyte differentiation. Results When human peripheral blood mononuclear cells (PBMCs were cultured with TLR3, TLR4, TLR5, TLR7, TLR8 or TLR9 agonists, there was no significant effect on fibrocyte differentiation, even though enhanced extracellular tumor necrosis factor (TNF-α accumulation and/or increased cell surface CD86 or major histocompatibility complex (MHC class II levels were observed. However, all TLR2 agonists tested inhibited fibrocyte differentiation without any significant effect on cell survival. Adding TLR2 agonists to purified monocytes had no effect on fibrocyte differentiation. However, some TLR2 agonists caused PBMCs to secrete a factor that inhibits the differentiation of purified monocytes into fibrocytes. This factor is not interferon (IFN-α, IFN-γ, interleukin (IL-12, aggregated immunoglobulin G (IgG or serum amyloid P (SAP, factors known to inhibit fibrocyte differentiation. TLR2 agonist-treated PBMCs secrete low levels of IL-6, TNF-α, IFN-γ, granulocyte colony-stimulating factor and tumor growth factor β1, but combinations of these factors had no effect on fibrocyte differentiation from purified monocytes. Conclusions Our results indicate that TLR2 agonists indirectly inhibit fibrocyte differentiation and that, for some TLR2 agonists, this inhibition involves other cell types in the PBMC population secreting an unknown factor that inhibits fibrocyte differentiation. Together, these data suggest that the presence of some bacterial signals can inhibit fibrocyte differentiation and may thus slow wound closure.

  8. MAM-2201, a synthetic cannabinoid drug of abuse, suppresses the synaptic input to cerebellar Purkinje cells via activation of presynaptic CB1 receptors.

    Science.gov (United States)

    Irie, Tomohiko; Kikura-Hanajiri, Ruri; Usami, Makoto; Uchiyama, Nahoko; Goda, Yukihiro; Sekino, Yuko

    2015-08-01

    Herbal products containing synthetic cannabinoids-initially sold as legal alternatives to marijuana-have become major drugs of abuse. Among the synthetic cannabinoids, [1-(5-fluoropentyl)-1H-indol-3-yl](4-methyl-1-naphthalenyl)-methanone (MAM-2201) has been recently detected in herbal products and has psychoactive and intoxicating effects in humans, suggesting that MAM-2201 alters brain function. Nevertheless, the pharmacological actions of MAM-2201 on cannabinoid receptor type 1 (CB1R) and neuronal functions have not been elucidated. We found that MAM-2201 acted as an agonist of human CB1Rs expressed in AtT-20 cells. In whole-cell patch-clamp recordings made from Purkinje cells (PCs) in slice preparations of the mouse cerebellum, we also found that MAM-2201 inhibited glutamate release at parallel fiber-PC synapses via activation of presynaptic CB1Rs. MAM-2201 inhibited neurotransmitter release with an inhibitory concentration 50% of 0.36 μM. MAM-2201 caused greater inhibition of neurotransmitter release than Δ(9)-tetrahydrocannabinol within the range of 0.1-30 μM and JWH-018, one of the most popular and potent synthetic cannabinoids detected in the herbal products, within the range of 0.03-3 μM. MAM-2201 caused a concentration-dependent suppression of GABA release onto PCs. Furthermore, MAM-2201 induced suppression of glutamate release at climbing fiber-PC synapses, leading to reduced dendritic Ca(2+) transients in PCs. These results suggest that MAM-2201 is likely to suppress neurotransmitter release at CB1R-expressing synapses in humans. The reduction of neurotransmitter release from CB1R-containing synapses could contribute to some of the symptoms of synthetic cannabinoid intoxication including impairments in cerebellum-dependent motor coordination and motor learning. PMID:25747605

  9. International Union of Basic and Clinical Pharmacology. LXXIX. Cannabinoid receptors and their ligands

    DEFF Research Database (Denmark)

    Pertwee, R G; Howlett, A C; Abood, M E;

    2010-01-01

    or channel. However, it does identify certain pharmacological targets that should be investigated further as potential CB(3) receptors or channels. These include TRP vanilloid 1, which possibly functions as an ionotropic cannabinoid receptor under physiological and/or pathological conditions, and some...... deorphanized GPCRs. Also discussed are 1) the ability of CB(1) receptors to form heteromeric complexes with certain other GPCRs, 2) phylogenetic relationships that exist between CB(1)/CB(2) receptors and other GPCRs, 3) evidence for the existence of several as-yet-uncharacterized non-CB(1), non-CB(2...

  10. Glucagon-like peptide 1 receptor agonist (GLP-1 RA)

    DEFF Research Database (Denmark)

    von Scholten, Bernt Johan; Hansen, Tine Willum; Goetze, Jens Peter;

    2015-01-01

    AIMS: In a short-term study including 31 patients with type 2 diabetes, glucagon-like peptide 1 receptor agonist (GLP-1 RA) treatment was associated with a significant reversible decline in GFR. Twenty-three patients re-initiated GLP-1 RA treatment after the primary study, and the aim...

  11. Nicotine reinforcement is reduced by cannabinoid CB1 receptor blockade in the ventral tegmental area.

    Science.gov (United States)

    Simonnet, Amelie; Cador, Martine; Caille, Stephanie

    2013-11-01

    Cannabinoid type 1 (CB1) receptors control the motivational properties and reinforcing effects of nicotine. Indeed, peripheral administration of a CB1 receptor antagonist dramatically decreases both nicotine taking and seeking. However, the neural substrates through which the cannabinoid CB1 receptors regulate the voluntary intake of nicotine remain to be elucidated. In the present study, we sought to determine whether central injections of a CB1 receptor antagonist delivered either into the ventral tegmental area (VTA) or the nucleus accumbens (NAC) may alter nicotine intravenous self-administration (IVSA). Rats were first trained to self-administer nicotine (30 μg/kg/0.1 ml). The effect of central infusions of the CB1 antagonist AM 251 (0, 1 and 10 μg/0.5 μl/side) on nicotine-taking behavior was then tested. Intra-VTA infusions of AM 251 dose dependently reduced IVSA with a significant decrease for the dose 10 μg/0.5 μl/side. Moreover, operant responding for water was unaltered by intra-VTA AM 251 at the same dose. Surprisingly, intra-NAC delivery of AM 251 did not alter nicotine behavior at all. These data suggest that in rats chronically exposed to nicotine IVSA, the cannabinoid CB1 receptors located in the VTA rather than in the NAC specifically control nicotine reinforcement and, subsequently, nicotine-taking behavior. PMID:22784230

  12. Small Molecules from Nature Targeting G-Protein Coupled Cannabinoid Receptors: Potential Leads for Drug Discovery and Development

    Directory of Open Access Journals (Sweden)

    Charu Sharma

    2015-01-01

    Full Text Available The cannabinoid molecules are derived from Cannabis sativa plant which acts on the cannabinoid receptors types 1 and 2 (CB1 and CB2 which have been explored as potential therapeutic targets for drug discovery and development. Currently, there are numerous cannabinoid based synthetic drugs used in clinical practice like the popular ones such as nabilone, dronabinol, and Δ9-tetrahydrocannabinol mediates its action through CB1/CB2 receptors. However, these synthetic based Cannabis derived compounds are known to exert adverse psychiatric effect and have also been exploited for drug abuse. This encourages us to find out an alternative and safe drug with the least psychiatric adverse effects. In recent years, many phytocannabinoids have been isolated from plants other than Cannabis. Several studies have shown that these phytocannabinoids show affinity, potency, selectivity, and efficacy towards cannabinoid receptors and inhibit endocannabinoid metabolizing enzymes, thus reducing hyperactivity of endocannabinoid systems. Also, these naturally derived molecules possess the least adverse effects opposed to the synthetically derived cannabinoids. Therefore, the plant based cannabinoid molecules proved to be promising and emerging therapeutic alternative. The present review provides an overview of therapeutic potential of ligands and plants modulating cannabinoid receptors that may be of interest to pharmaceutical industry in search of new and safer drug discovery and development for future therapeutics.

  13. Cannabinoid 2 (CB2) receptor agonism reduces lithium chloride-induced vomiting in Suncus murinus and nausea-induced conditioned gaping in rats.

    Science.gov (United States)

    Rock, Erin M; Boulet, Nathalie; Limebeer, Cheryl L; Mechoulam, Raphael; Parker, Linda A

    2016-09-01

    We aimed to investigate the potential anti-emetic and anti-nausea properties of targeting the cannabinoid 2 (CB2) receptor. We investigated the effect of the selective CB2 agonist, HU-308, on lithium chloride- (LiCl) induced vomiting in Suncus murinus (S. murinus) and conditioned gaping (nausea-induced behaviour) in rats. Additionally, we determined whether these effects could be prevented by pretreatment with AM630 (a selective CB2 receptor antagonist/inverse agonist). In S. murinus, HU-308 (2.5, 5mg/kg, i.p.) reduced, but did not completely block, LiCl-induced vomiting; an effect that was prevented with AM630. In rats, HU-308 (5mg/kg, i.p.) suppressed, but did not completely block, LiCl-induced conditioned gaping to a flavour; an effect that was prevented by AM630. These findings are the first to demonstrate the ability of a selective CB2 receptor agonist to reduce nausea in animal models, indicating that targeting the CB2 receptor may be an effective strategy, devoid of psychoactive effects, for managing toxin-induced nausea and vomiting. PMID:27263826

  14. The cannabinoid receptor type 2 promotes cardiac myocyte and fibroblast survival and protects against ischemia/reperfusion-induced cardiomyopathy.

    Science.gov (United States)

    Defer, Nicole; Wan, Jinghong; Souktani, Richard; Escoubet, Brigitte; Perier, Magali; Caramelle, Philippe; Manin, Sylvie; Deveaux, Vanessa; Bourin, Marie-Claude; Zimmer, Andreas; Lotersztajn, Sophie; Pecker, Françoise; Pavoine, Catherine

    2009-07-01

    Post-myocardial infarction (MI) heart failure is a major public health problem in Western countries and results from ischemia/reperfusion (IR)-induced cell death, remodeling, and contractile dysfunction. Ex vivo studies have demonstrated the cardioprotective anti-inflammatory effect of the cannabinoid type 2 (CB2) receptor agonists within hours after IR. Herein, we evaluated the in vivo effect of CB2 receptors on IR-induced cell death, fibrosis, and cardiac dysfunction and investigated the target role of cardiac myocytes and fibroblasts. The infarct size was increased 24 h after IR in CB2(-/-) vs. wild-type (WT) hearts and decreased when WT hearts were injected with the CB2 agonist JWH133 (3 mg/kg) at reperfusion. Compared with WT hearts, CB2(-/-) hearts showed widespread injury 3 d after IR, with enhanced apoptosis and remodeling affecting the remote myocardium. Finally, CB2(-/-) hearts exhibited exacerbated fibrosis, associated with left ventricular dysfunction 4 wk after IR, whereas their WT counterparts recovered normal function. Cardiac myocytes and fibroblasts isolated from CB2(-/-) hearts displayed a higher H(2)O(2)-induced death than WT cells, whereas 1 microM JWH133 triggered survival effects. Furthermore, H(2)O(2)-induced myofibroblast activation was increased in CB2(-/-) fibroblasts but decreased in 1 microM JWH133-treated WT fibroblasts, compared with that in WT cells. Therefore, CB2 receptor activation may protect against post-IR heart failure through direct inhibition of cardiac myocyte and fibroblast death and prevention of myofibroblast activation.

  15. The Cannabinoid Receptor CB1 Interacts with the WAVE1 Complex and Plays a Role in Actin Dynamics and Structural Plasticity in Neurons.

    Science.gov (United States)

    Njoo, Christian; Agarwal, Nitin; Lutz, Beat; Kuner, Rohini

    2015-10-01

    The molecular composition of the cannabinoid type 1 (CB1) receptor complex beyond the classical G-protein signaling components is not known. Using proteomics on mouse cortex in vivo, we pulled down proteins interacting with CB1 in neurons and show that the CB1 receptor assembles with multiple members of the WAVE1 complex and the RhoGTPase Rac1 and modulates their activity. Activation levels of CB1 receptor directly impacted on actin polymerization and stability via WAVE1 in growth cones of developing neurons, leading to their collapse, as well as in synaptic spines of mature neurons, leading to their retraction. In adult mice, CB1 receptor agonists attenuated activity-dependent remodeling of dendritic spines in spinal cord neurons in vivo and suppressed inflammatory pain by regulating the WAVE1 complex. This study reports novel signaling mechanisms for cannabinoidergic modulation of the nervous system and demonstrates a previously unreported role for the WAVE1 complex in therapeutic applications of cannabinoids.

  16. HindIII identifies a two allele DNA polymorphism of the human cannabinoid receptor gene (CNR)

    Energy Technology Data Exchange (ETDEWEB)

    Caenazzo, L.; Hoehe, M.R.; Hsieh, W.T.; Berrettini, W.H.; Bonner, T.I.; Gershon, E.S. (National Inst. of Health, Bethesda, MD (United States))

    1991-09-11

    HCNR p5, a 0.9 kb BamHI/EcoRI fragment from the human cannabinoid receptor gene inserted into pUC19, was used as probe. The fragment is located in an intron approximately 14 kb 5{prime} of the initiation codon. This fragment is a clean single copy sequence by genomic blotting. Hybridization of human genomic DNA digested with HindIII identified a two allele RFLP with bands at 5.5 (A1) and 3.3 kb (A2). The human cannabinoid receptor gene has been genetically mapped in CEPH reference pedigrees to the centromeric/q region of chromosome 6. In situ hybridization localizes it to 6q14-q15. Codominant segregation has been observed in 26 informative two- and three-generation CEPH pedigrees and in 14 medium-sized disease families.

  17. Cannabinoid 1 and transient receptor potential vanilloid 1 receptors discretely modulate evoked glutamate separately from spontaneous glutamate transmission.

    Science.gov (United States)

    Fawley, Jessica A; Hofmann, Mackenzie E; Andresen, Michael C

    2014-06-11

    Action potentials trigger synaptic terminals to synchronously release vesicles, but some vesicles release spontaneously. G-protein-coupled receptors (GPCRs) can modulate both of these processes. At cranial primary afferent terminals, the GPCR cannabinoid 1 (CB1) is often coexpressed with transient receptor potential vanilloid 1 (TRPV1), a nonselective cation channel present on most afferents. Here we tested whether CB1 activation modulates synchronous, action potential-evoked (eEPSCs) and/or spontaneous (sEPSCs) EPSCs at solitary tract nucleus neurons. In rat horizontal brainstem slices, activation of solitary tract (ST) primary afferents generated ST-eEPSCs that were rapidly and reversibly inhibited from most afferents by activation of CB1 with arachidonyl-2'-chloroethylamide (ACEA) or WIN 55,212-2 [R-(+)-(2,3-dihydro-5-methyl-3-[(4-morpholinyl)methyl]pyrrolo[1,2,3-de]-1,4-benzoxazin-6-yl)(1-naphthalenyl) methanone monomethanesulfonate]. The CB1 antagonist/inverse agonist AM251 [N-1-(2,4-dichlorophenyl)-5-(4-iodophenyl)-4-methyl-N-1-piperidinyl-1H-pyrazole-3-carboxamide] blocked these responses. Despite profound depression of ST-eEPSCs during CB1 activation, sEPSCs in these same neurons were unaltered. Changes in temperature changed sEPSC frequency only from TRPV1(+) afferents (i.e., thermal sEPSC responses only occurred in TRPV1(+) afferents). CB1 activation failed to alter these thermal sEPSC responses. However, the endogenous arachidonate metabolite N-arachidonyldopamine (NADA) promiscuously activated both CB1 and TRPV1 receptors. NADA inhibited ST-eEPSCs while simultaneously increasing sEPSC frequency, and thermally triggered sEPSC increases in neurons with TRPV1(+) afferents. We found no evidence for CB1/TRPV1 interactions suggesting independent regulation of two separate vesicle pools. Together, these data demonstrate that action potential-evoked synchronous glutamate release is modulated separately from TRPV1-mediated glutamate release despite coexistence

  18. The cannabinoid receptor 1 associates with NMDA receptors to produce glutamatergic hypofunction: implications in psychosis and schizophrenia.

    Directory of Open Access Journals (Sweden)

    Pilar eSánchez-Blázquez

    2014-01-01

    Full Text Available The endocannabinoid system is widespread throughout the central nervous system and its type 1 receptor (CB1 plays a crucial role in preventing the neurotoxicity caused by activation of glutamate N-methyl-D-aspartate receptors (NMDARs. Indeed, it is the activity of NMDARs themselves that provides the demands on the endogenous cannabinoids in order to control their calcium currents. Therefore, a physiological role of this system is to maintain NMDAR activity within safe limits, thereby protecting neural cells from excitotoxicity. Thus, cannabinoids may be able to control NMDAR overactivation-related neural dysfunctions; however the major obstacles to the therapeutic utilization of these compounds are their psychotropic effects and negative influence on cognitive performance. Studies in humans have indicated that abuse of smoked cannabis can promote psychosis and even circumstantially precipitate symptoms of schizophrenia, although the latter appears to require a prior vulnerability in the individual. It is possible that cannabinoids provoke psychosis/schizophrenia reflecting a mechanism common to neuroprotection the reduction of NMDAR activity. Cannabinoids are proposed to produce such effect by reducing the pre-synaptic release of glutamate or interfering with postsynaptic NMDAR-regulated signaling pathways. The efficacy of such control requires the endocannabinoid system to apply its negative influence in a manner that is proportional to the strength of NMDAR signaling. Thus, cannabinoids acting at the wrong time or exerting an inappropriate influence on their receptors may cause NMDAR hypofunction. The purpose of the present review is to draw the attention of the reader to the newly described functional and physical CB1-NMDAR association, which may elucidate the scenario required for the rapid and efficacious control of NMDAR activity. Whether alterations in these mechanisms may increase NMDAR hypofunction leading to vulnerability to

  19. Identification of human dopamine receptors agonists from Chinese herbs

    Institute of Scientific and Technical Information of China (English)

    Yi-lin ZHANG; Hai-qing ZHANG; Xiao-yu LIU; Shi-neng HUA; Lu-bing ZHOU; Jun YU; Xue-hai TAN

    2007-01-01

    Aim: To find human dopamine receptors, especially D1-like receptor specific ago-nists from Chinese herbs as potential antihypertension drug leads. Methods: Two D1-like receptor cell lines carrying a β-lactamase reporter gene, and a D2 receptor cell line coexpressing a promiscuous G protein G15 were constructed using HEK293 cells. A natural compound library made from fractionated samples of herbal ex-tracts was used for high-throughput screening (HTS) against one of the cell lines,HEK/D5R/CRE-blax. The interested hits were evaluated for their activities against various dopamine receptors. Results: Fourteen hits were identified from primary screening, of which 2 of the better hit samples, HD0522 and HD0059, were selected for further material and activity analysis, and to obtain 2 compounds that ap-peared as 2 single peaks in HPLC, HD0522H01 and HD0059H01. HD0059H01 could activate D1, D2, and D5 receptors, with EC50 values of 2.28 μg/mL, 0.85 μg/mL, and 1.41 μg/mL, respectively. HD0522H01 could only activate D1R and D5R with EC50 values of 2.95 μg/mL and 8.38 μg/mL. Conclusion: We established cell-based assays for 3 different human dopamine receptors and identified specific agonists HD0522H01 and HD0059H01 through HTS. The specific agonist to D1-like receptors, HD0522H01, may become a new natural product-based drug lead for antihypertension treatment.

  20. Agonist discrimination between AMPA receptor subtypes

    DEFF Research Database (Denmark)

    Coquelle, T; Christensen, J K; Banke, T G;

    2000-01-01

    The lack of subtype-selective compounds for AMPA receptors (AMPA-R) led us to search for compounds with such selectivity. Homoibotenic acid analogues were investigated at recombinant GluR1o, GluR2o(R), GluR3o and GluR1o + 3o receptors expressed in Sf9 insect cells and affinities determined in [3H......]AMPA radioligand binding experiments. (S)-4-bromohomoibotenic acid (BrHIBO) exhibited a 126-fold selectivity for GluR1o compared to GluR3o. Xenopus laevis oocytes were used to express functional homomeric and heteromeric recombinant AMPA-R and to determine BrHIBO potency (EC50) at these channels. (R......,S)-BrHIBO exhibited a 37-fold selectivity range amongst the AMPA-R. It is hoped that BrHIBO can be used as a lead structure for the development of other subtype-selective compounds....

  1. A study of cannabinoid-1 receptors during the early phase of excitotoxic damage to rat spinal locomotor networks in vitro.

    Science.gov (United States)

    Veeraraghavan, Priyadharishini; Dekanic, Ana; Nistri, Andrea

    2016-10-01

    Endocannabinoids acting on cannabinoid-1 receptors (CB1Rs) are proposed to protect brain and spinal neurons from excitotoxic damage. The ability to recover from spinal cord injury (SCI), in which excitotoxicity is a major player, is usually investigated at late times after modulation of CB1Rs whose role in the early phases of SCI remains unclear. Using the rat spinal cord in vitro as a model for studying SCI initial pathophysiology, we investigated if agonists or antagonists of CB1Rs might affect SCI induced by the excitotoxic agent kainate (KA) within 24h from a transient (1h) application of this glutamate agonist. The CB1 agonist anandamide (AEA or pharmacological block of its degradation) did not limit excitotoxic depolarization of spinal networks: cyclic adenosine monophosphate (cAMP) assay demonstrated that CB1Rs remained functional 24h later and similarly expressed among dead or survived cells. Locomotor-like network activity recorded from ventral roots could not recover with such treatments and was associated with persistent depression of synaptic transmission. Motoneurons, that are particularly vulnerable to KA, were not protected by AEA. Application of 2-arachidonoylglycerol also did not attenuate the electrophysiological and histological damage. The intensification of damage by the CB1 antagonist AM251 suggested that endocannabinoids were operative after excitotoxic stimulation, yet insufficient to contrast it efficiently. The present data indicate that the early phases of excitotoxic SCI could not be arrested by pharmacologically exploiting the endocannabinoid system, consistent with the notion that AEA and its derivatives are more useful to treat late SCI phases. PMID:27450568

  2. Cannabinoid Receptors CB1 and CB2 Modulate the Electroretinographic Waves in Vervet Monkeys

    Directory of Open Access Journals (Sweden)

    Joseph Bouskila

    2016-01-01

    Full Text Available The expression patterns of the cannabinoid receptor type 1 (CB1R and the cannabinoid receptor type 2 (CB2R are well documented in rodents and primates. In vervet monkeys, CB1R is present in the retinal neurons (photoreceptors, horizontal cells, bipolar cells, amacrine cells, and ganglion cells and CB2R is exclusively found in the retinal glia (Müller cells. However, the role of these cannabinoid receptors in normal primate retinal function remains elusive. Using full-field electroretinography in adult vervet monkeys, we recorded changes in neural activity following the blockade of CB1R and CB2R by the intravitreal administration of their antagonists (AM251 and AM630, resp. in photopic and scotopic conditions. Our results show that AM251 increases the photopic a-wave amplitude at high flash intensities, whereas AM630 increases the amplitude of both the photopic a- and b-waves. In scotopic conditions, both blockers increased the b-wave amplitude but did not change the a-wave amplitude. These findings suggest an important role of CB1R and CB2R in primate retinal function.

  3. Cannabinoid receptors in submandibular acinar cells: functional coupling between saliva fluid and electrolytes secretion and Ca2+ signalling.

    Science.gov (United States)

    Kopach, Olga; Vats, Juliana; Netsyk, Olga; Voitenko, Nana; Irving, Andrew; Fedirko, Nataliya

    2012-04-15

    Cannabinoid receptors (CBRs) belong to the G protein-coupled receptor superfamily, and activation of CBRs in salivary cells inhibits agonist-stimulated salivation and modifies saliva content. However, the role of different CBR subtypes in acinar cell physiology and in intracellular signalling remains unclear. Here, we uncover functional CB(1)Rs and CB(2)Rs in acinar cells of rat submandibular gland and their essential role in saliva secretion. Pharmacological activation of CB(1)Rs and CB(2)Rs in the submandibular gland suppressed saliva outflow and modified saliva content produced by the submandibular gland in vivo. Using Na(+)-selective microelectrodes to record secretory Na(+) responses in the lumen of acini, we observed a reduction in Na(+) transport following the activation of CBRs, which was counteracted by the selective CB(1)R antagonist AM251. In addition, activation of CB(1)Rs or CB Rs caused inhibition of Na(+)-K(+) 2 -ATPase activity in microsomes derived from the gland tissue as well as in isolated acinar cells. Using a Ca(2+) imaging technique, we showed that activation of CB(1)Rs and CB(2)Rs alters [Ca(2+)](cyt) signalling in acinar cells by distinct pathways, involving Ca(2+) release from the endoplasmic reticulum (ER) and store-operated Ca(2+) entry (SOCE), respectively. Our data demonstrate the expression of CB(1)Rs and CB(2)Rs in acinar cells, and their involvement in the regulation of salivary gland functioning.

  4. Cannabinoid, melanocortin and opioid receptor expression on DRD1 and DRD2 subpopulations in rat striatum

    Directory of Open Access Journals (Sweden)

    Ralph J Oude-Ophuis

    2014-03-01

    Full Text Available The striatum harbors two neuronal populations that enable action selection. One population represents the striatonigral pathway, expresses the dopamine receptor D1 (DRD1 and promotes the execution of motor programs, while the other population represents the striatopallidal pathway, expresses the dopamine receptor D2 (DRD2 and suppresses voluntary activity. The two populations integrate distinct sensorimotor, cognitive and emotional information streams and their combined activity enables the selection of adaptive behaviors. Characterization of these populations is critical to the understanding of their role in action selection, because it aids the identification of the molecular mechanisms that separate them. To that end, we used fluorescent in-situ hybridization to quantify the percentage of striatal cells that (coexpress dopaminergic receptors and receptors of the cannabinoid, melanocortin or opioid neurotransmitters systems. Our main findings are that the cannabinoid 1 receptor is equally expressed on both populations with a gradient from dorsal to ventral striatum, that the opioid receptors have a preference for expression with either the DRD1 or DRD2 and that the melanocortin 4 receptor (MC4R is predominantly expressed in ventral parts of the striatum. In addition, we find that the level of MC4R expression determines its localization to either the DRD1 or the DRD2 population. Thereby, we provide insight into the sensitivity of the two dopaminoceptive populations to these neurotransmitters and progress the understanding of the mechanisms that enable action selection.

  5. Δ9-Tetrahydrocannabinol enhances MCF-7 cell proliferation via cannabinoid receptor-independent signaling

    International Nuclear Information System (INIS)

    We recently reported that Δ9-tetrahydrocannabinol (Δ9-THC) has the ability to stimulate the proliferation of human breast carcinoma MCF-7 cells. However, the mechanism of action remains to be clarified. The present study focused on the relationship between receptor expression and the effects of Δ9-THC on cell proliferation. RT-PCR analysis demonstrated that there was no detectable expression of CB receptors in MCF-7 cells. In accordance with this, no effects of cannabinoid 1/2 (CB1/2) receptor antagonists and pertussis toxin on cell proliferation were observed. Although MCF-7 cell proliferation is suggested to be suppressed by Δ9-THC in the presence of CB receptors, it was revealed that Δ9-THC could exert upregulation of living cells in the absence of the receptors. Interestingly, Δ9-THC upregulated human epithelial growth factor receptor type 2 (HER2) expression, which is known to be a predictive factor of human breast cancer and is able to stimulate cancer cells as well as MCF-7 cells. Actinomycin D-treatment interfered with the upregulation of HER2 and cell proliferation by cannabinoid. Taken together, these studies suggest that, in the absence of CB receptors, Δ9-THC can stimulate the proliferation of MCF-7 cells by modulating, at least in part, HER2 transcription

  6. Stabilization of functional recombinant cannabinoid receptor CB(2 in detergent micelles and lipid bilayers.

    Directory of Open Access Journals (Sweden)

    Krishna Vukoti

    Full Text Available Elucidation of the molecular mechanisms of activation of G protein-coupled receptors (GPCRs is among the most challenging tasks for modern membrane biology. For studies by high resolution analytical methods, these integral membrane receptors have to be expressed in large quantities, solubilized from cell membranes and purified in detergent micelles, which may result in a severe destabilization and a loss of function. Here, we report insights into differential effects of detergents, lipids and cannabinoid ligands on stability of the recombinant cannabinoid receptor CB(2, and provide guidelines for preparation and handling of the fully functional receptor suitable for a wide array of downstream applications. While we previously described the expression in Escherichia coli, purification and liposome-reconstitution of multi-milligram quantities of CB(2, here we report an efficient stabilization of the recombinant receptor in micelles - crucial for functional and structural characterization. The effects of detergents, lipids and specific ligands on structural stability of CB(2 were assessed by studying activation of G proteins by the purified receptor reconstituted into liposomes. Functional structure of the ligand binding pocket of the receptor was confirmed by binding of (2H-labeled ligand measured by solid-state NMR. We demonstrate that a concerted action of an anionic cholesterol derivative, cholesteryl hemisuccinate (CHS and high affinity cannabinoid ligands CP-55,940 or SR-144,528 are required for efficient stabilization of the functional fold of CB(2 in dodecyl maltoside (DDM/CHAPS detergent solutions. Similar to CHS, the negatively charged phospholipids with the serine headgroup (PS exerted significant stabilizing effects in micelles while uncharged phospholipids were not effective. The purified CB(2 reconstituted into lipid bilayers retained functionality for up to several weeks enabling high resolution structural studies of this GPCR at

  7. Mice Expressing a "Hyper-Sensitive" Form of the Cannabinoid Receptor 1 (CB1) Are Neither Obese Nor Diabetic.

    Science.gov (United States)

    Marcus, David J; Zee, Michael L; Davis, Brian J; Haskins, Chris P; Andrews, Mary-Jeanette; Amin, Randa; Henderson-Redmond, Angela N; Mackie, Ken; Czyzyk, Traci A; Morgan, Daniel J

    2016-01-01

    Multiple lines of evidence implicate the endocannabinoid signaling system in the modulation of metabolic disease. Genetic or pharmacological inactivation of CB1 in rodents leads to reduced body weight, resistance to diet-induced obesity, decreased intake of highly palatable food, and increased energy expenditure. Cannabinoid agonists stimulate feeding in rodents and increased levels of endocannabinoids can disrupt lipid metabolism. Therefore, the hypothesis that sustained endocannabinoid signaling can lead to obesity and diabetes was examined in this study using S426A/S430A mutant mice expressing a desensitization-resistant CB1 receptor. These mice display exaggerated and prolonged responses to acute administration of phytocannabinoids, synthetic cannabinoids, and endocannabinoids. As a consequence these mice represent a novel model for determining the effect of enhanced endocannabinoid signaling on metabolic disease. S426A/S430A mutants consumed equivalent amounts of both high fat (45%) and low fat (10%) chow control diet compared to wild-type littermate controls. S426A/S430A mutants and wild-type mice fed either high or low fat control diet displayed similar fasting blood glucose levels and normal glucose clearance following a 2 g/kg glucose challenge. Furthermore, S426A/S430A mutants and wild-type mice consumed similar amounts of chow following an overnight fast. While both THC and JZL195 significantly increased food intake two hours after injection, this increase was similar between the S426A/S430A mutant and wildtype control mice Our results indicate that S426A/S430A mutant mice expressing the desensitization-resistant form of CB1 do not exhibit differences in body weight, food intake, glucose homeostasis, or re-feeding following a fast. PMID:27501235

  8. Effects of cannabinoid CB(1) receptor agonism and antagonism on SKF81297-induced dyskinesia and haloperidol-induced dystonia in Cebus apella monkeys

    DEFF Research Database (Denmark)

    Madsen, Morten V; Peacock, Linda P; Werge, Thomas;

    2011-01-01

    . Endocannabinoids modulate striatal dopamine activity via type 1 cannabinoid (CB(1)) receptors, and studies in rats and humans suggest beneficial effects of CB(1) ligands on EPS. The present study explored the effects of CB(1) receptor ligands on oral dyskinesia induced by the dopamine D(1) receptor agonist SKF......81297 (SKF) and acute dystonia induced by the dopamine D(2) receptor antagonist haloperidol in Cebus apella monkeys. The monkeys were sensitised to EPS by prior exposure to D(2) receptor antagonists. SKF (0.3 mg/kg) was administered alone and in combination with the CB(1) agonist CP55,940 (0.......0025-0.01 mg/kg) or the CB(1) antagonist SR141716A (0.25-0.75 mg/kg). Haloperidol (individual doses at 0.01-0.02 mg/kg) was administered alone and in combination with CP55,940 (0.005 or 0.01 mg/kg) or SR141716A (0.5 or 0.75 mg/kg). Subsequently, the monkeys were videotaped, and the recordings were rated...

  9. Narrow SAR in odorant sensing Orco receptor agonists.

    Science.gov (United States)

    Romaine, Ian M; Taylor, Robert W; Saidu, Samsudeen P; Kim, Kwangho; Sulikowski, Gary A; Zwiebel, Laurence J; Waterson, Alex G

    2014-06-15

    The systematic exploration of a series of triazole-based agonists of the cation channel insect odorant receptor is reported. The structure-activity relationships of independent sections of the molecules are examined. Very small changes to the compound structure were found to exert a large impact on compound activity. Optimal substitutions were combined using a 'mix-and-match' strategy to produce best-in-class compounds that are capable of potently agonizing odorant receptor activity and may form the basis for the identification of a new mode of insect behavior modification. PMID:24813736

  10. The combined inhibitory effect of the adenosine A1 and cannabinoid CB1 receptors on cAMP accumulation in the hippocampus is additive and independent of A1 receptor desensitization.

    Science.gov (United States)

    Serpa, André; Correia, Sara; Ribeiro, Joaquim A; Sebastião, Ana M; Cascalheira, José F

    2015-01-01

    Adenosine A1 and cannabinoid CB1 receptors are highly expressed in hippocampus where they trigger similar transduction pathways. We investigated how the combined acute activation of A1 and CB1 receptors modulates cAMP accumulation in rat hippocampal slices. The CB1 agonist WIN55212-2 (0.3-30 μM) decreased forskolin-stimulated cAMP accumulation with an EC50 of 6.6±2.7 μM and an Emax of 31%±2%, whereas for the A1 agonist, N6-cyclopentyladenosine (CPA, 10-150 nM), an EC50 of 35±19 nM, and an Emax of 29%±5 were obtained. The combined inhibitory effect of WIN55212-2 (30 μM) and CPA (100 nM) on cAMP accumulation was 41%±6% (n=4), which did not differ (P>0.7) from the sum of the individual effects of each agonist (43%±8%) but was different (PCB1 and A1 receptors on cAMP formation is additive and CB1 receptor activity is not affected by short-term A1 receptor desensitization.

  11. Evidence for association between polymorphisms in the Cannabinoid Receptor 1 (CNR1) gene and cannabis dependence

    OpenAIRE

    Agrawal, Arpana; Wetherill, Leah; Dick, Danielle M; Xuei, Xiaoling; Hinrichs, Anthony; Hesselbrock, Victor; Kramer, John; Nurnberger, John I.; Schuckit, Marc; Laura J Bierut; Edenberg, Howard J.; Foroud, Tatiana

    2009-01-01

    Genomic studies of cannabis use disorders have been limited. The cannabinoid receptor 1 gene (CNR1) on chromosome 6q14–15 is an excellent candidate gene for cannabis dependence due to the important role of the G-protein coupled receptor encoded by this gene in the rewarding effects of Δ9-tetrahydrocannabinol. Previous studies have found equivocal evidence for an association between SNPs in CNR1 and a general vulnerability to substance use disorders. We investigate the association between 9 SN...

  12. Astroglial CB1 cannabinoid receptors regulate leptin signaling in mouse brain astrocytes.

    Science.gov (United States)

    Bosier, Barbara; Bellocchio, Luigi; Metna-Laurent, Mathilde; Soria-Gomez, Edgar; Matias, Isabelle; Hebert-Chatelain, Etienne; Cannich, Astrid; Maitre, Marlène; Leste-Lasserre, Thierry; Cardinal, Pierre; Mendizabal-Zubiaga, Juan; Canduela, Miren Josune; Reguero, Leire; Hermans, Emmanuel; Grandes, Pedro; Cota, Daniela; Marsicano, Giovanni

    2013-01-01

    Type-1 cannabinoid (CB1) and leptin (ObR) receptors regulate metabolic and astroglial functions, but the potential links between the two systems in astrocytes were not investigated so far. Genetic and pharmacological manipulations of CB1 receptor expression and activity in cultured cortical and hypothalamic astrocytes demonstrated that cannabinoid signaling controls the levels of ObR expression. Lack of CB1 receptors also markedly impaired leptin-mediated activation of signal transducers and activators of transcription 3 and 5 (STAT3 and STAT5) in astrocytes. In particular, CB1 deletion determined a basal overactivation of STAT5, thereby leading to the downregulation of ObR expression, and leptin failed to regulate STAT5-dependent glycogen storage in the absence of CB1 receptors. These results show that CB1 receptors directly interfere with leptin signaling and its ability to regulate glycogen storage, thereby representing a novel mechanism linking endocannabinoid and leptin signaling in the regulation of brain energy storage and neuronal functions.

  13. Effects of Intra-Amygdala Infusion of CB1 Receptor Agonists on the Reconsolidation of Fear-Potentiated Startle

    Science.gov (United States)

    Lin, Hui-Ching; Mao, Sheng-Chun; Gean, Po-Wu

    2006-01-01

    The cannabinoid CB1 receptor has been shown to be critically involved in the extinction of fear memory. Systemic injection of a CB1 receptor antagonist prior to extinction training blocked extinction. Conversely, administration of the cannabinoid uptake inhibitor AM404 facilitated extinction in a dose-dependent manner. Here we show that bilateral…

  14. Cryptochinones from Cryptocarya chinensis act as farnesoid X receptor agonists.

    Science.gov (United States)

    Lin, Hsiang-Ru; Chou, Tsung-Hsien; Huang, Din-Wen; Chen, Ih-Sheng

    2014-09-01

    Cryptochinones A-D are tetrahydroflavanones isolated from the leaves of Cryptocarya chinensis, an evergreen tree whose extracts are believed to have a variety of health benefits. The origin of their possible bioactivity is unclear. The farnesoid X receptor (FXR) is a member of nuclear receptor superfamily that has been widely targeted for developing treatments for chronic liver disease and for hyperglycemia. We studied whether cryptochinones A-D, which are structurally similar to known FXR ligands, may act at this target. Indeed, in mammalian one-hybrid and transient transfection reporter assays, cryptochinones A-D transactivated FXR to modulate promoter action including GAL4, SHP, CYP7A1, and PLTP promoters in dose-dependent manner, while they exhibited similar agonistic activity as chenodeoxycholic acid (CDCA), an endogenous FXR agonist. Through molecular modeling docking studies we evaluated their ability to bind to the FXR ligand binding pocket. Our results indicate that cryptochinones A-D can behave as FXR agonists. PMID:25127166

  15. Peripheral Cannabinoid-1 Receptor Inverse Agonism Reduces Obesity by Reversing Leptin Resistance

    OpenAIRE

    Tam, Joseph; Cinar, Resat; Liu, Jie; Godlewski, Grzegorz; Wesley, Daniel; Jourdan, Tony; Szanda, Gergö; Mukhopadhyay, Bani; Chedester, Lee; Liow, Jeih-San; Innis, Robert B.; Cheng, Kejun; Rice, Kenner C.; Deschamps, Jeffrey R.; Chorvat, Robert J.

    2012-01-01

    Obesity-related leptin resistance manifests in loss of leptin’s ability to reduce appetite and increase energy expenditure. Obesity is also associated with increased activity of the endocannabinoid system, and CB1 receptor (CB1R) inverse agonists reduce body weight and the associated metabolic complications, although adverse neuropsychiatric effects halted their therapeutic development. Here we show that in mice with diet-induced obesity (DIO), the peripherally restricted CB1R inverse agonist...

  16. Synthesis and structure-activity relationships of novel indazolyl glucocorticoid receptor partial agonists.

    Science.gov (United States)

    Gilmore, John L; Sheppeck, James E; Wang, Jim; Dhar, T G Murali; Cavallaro, Cullen; Doweyko, Arthur M; Mckay, Lorraine; Cunningham, Mark D; Habte, Sium F; Nadler, Steven G; Dodd, John H; Somerville, John E; Barrish, Joel C

    2013-10-01

    SAR was used to further develop an indazole class of non-steroidal glucocorticoid receptor agonists aided by a GR LBD (ligand-binding domain)-agonist co-crystal structure described in the accompanying paper. Progress towards discovering a dissociated GR agonist guided by human in vitro assays biased the optimization of this compound series towards partial agonists that possessed excellent selectivity against other nuclear hormone receptors. PMID:23916594

  17. Resistance to diet-induced adiposity in cannabinoid receptor-1 deficient mice is not due to impaired adipocyte function

    NARCIS (Netherlands)

    Oosterveer, Maaike H.; Koolman, Anniek H.; de Boer, Pieter T.; Bos, Trijnie; Bleeker, Aycha; Bloks, Vincent W.; Kuipers, Folkert; Sauer, Pieter J. J.; van Dijk, Gertjan

    2011-01-01

    Background: Overactivity and/or dysregulation of the endocannabinoid system (ECS) contribute to development of obesity. In vitro studies indicate a regulatory role for the cannabinoid receptor 1 (CB1) in adipocyte function and CB1-receptor deficient (CB1-/-) mice are resistant to high fat diet-induc

  18. Blockade of cannabinoid CB receptor function protects against in vivo disseminating brain damage following NMDA-induced excitotoxicity

    DEFF Research Database (Denmark)

    Hansen, H.H.; Ramos, J.A.; Fernández-Ruiz, J.;

    2002-01-01

    The ability of cannabinoid CB, receptors to influence glutamatergic excitatory neurotransmission has fueled interest in how these receptors and their endogenous ligands may interact in conditions of excitotoxic insults. The present study characterized the impact of stimulated and inhibited CB rec...

  19. Celastrol Attenuates Inflammatory and Neuropathic Pain Mediated by Cannabinoid Receptor Type 2

    Directory of Open Access Journals (Sweden)

    Longhe Yang

    2014-08-01

    Full Text Available Celastrol, a major active ingredient of Chinese herb Tripterygium wilfordii Hook. f. (thunder god vine, has exhibited a broad spectrum of pharmacological activities, including anti-inflammation, anti-cancer and immunosuppression. In the present study, we used animal models of inflammatory pain and neuropathic pain, generated by carrageenan injection and spared nerve injury (SNI, respectively, to evaluate the effect of celastrol and to address the mechanisms underlying pain processing. Intraperitoneal (i.p. injection of celastrol produced a dose-dependent inhibition of carrageenan-induced edema and allodynia. Real-time PCR analysis showed that celastrol (0.3 mg/kg, i.p. significantly reduced mRNA expressions of inflammatory cytokines, TNF-α, IL-6, IL-1β, in carrageenan-injected mice. In SNI mice, pain behavior studies showed that celastrol (1 mg/kg, i.p. effectively prevented the hypersensitivity of mechanical nociceptive response on the third day post-surgery and the seventh day post-surgery. Furthermore, the anti-hyperalgesic effects of celastrol in carrageenan-injected mice and SNI mice were reversed by SR144528 (1 mg/kg, i.p., a specific cannabinoid receptor-2 (CB2 receptor antagonist, but not by SR141716 (1 mg/kg, i.p., a specific cannabinoid receptor-1 (CB1 receptor antagonist. Taken together, our results demonstrate the analgesia effects of celastrol through CB2 signaling and propose the potential of exploiting celastrol as a novel candidate for pain relief.

  20. Distinct conformational changes in activated agonist-bound and agonist-free glycine receptor subunits

    DEFF Research Database (Denmark)

    Pless, Stephan Alexander; Lynch, Joseph W

    2009-01-01

    glycine-free or a glycine-bound subunit. Agonist-free subunits were created by incorporating T204A and R65K mutations, which disrupted glycine binding to both (+) and (-) subunit interfaces. In heteromeric receptors comprising wild-type and R65K,T204A,R271C triple-mutant subunits, the fluorescence...... response exhibited a drastically reduced glycine sensitivity relative to the current response. Two conclusions can be drawn from this. First, because the labeled glycine-free subunits were activated by glycine binding to neighboring wild-type subunits, our results provide evidence for a cooperative...... activation mechanism. However, because the fluorescent label on glycine-free subunits does not reflect movements at the channel gate, we conclude that glycine binding also produces a local non-concerted conformational change that is not essential for receptor activation....

  1. Chronic Cannabinoid Administration in Vivo Compromises Extinction of Fear Memory

    Science.gov (United States)

    Lin, Hui-Ching; Mao, Sheng-Chun; Chen, Po-See; Gean, Po-Wu

    2008-01-01

    Endocannabinoids are critically involved in the extinction of fear memory. Here we examined the effects of repeated cannabinoid administration on the extinction of fear memory in rats and on inhibitory synaptic transmission in medial prefrontal cortex (mPFC) slices. Rats were treated with the CB1 receptor agonist WIN55212-2 (WIN 10 mg/kg, i.p.)…

  2. N-methyl-D-aspartic acid receptor agonists

    DEFF Research Database (Denmark)

    Madsen, U; Frydenvang, Karla Andrea; Ebert, B;

    1996-01-01

    (R,S)-2-Amino-2-(3-hydroxy-5-methyl-4-isoxazolyl)acetic acid [(R,S)-AMAA, 4] is a potent and selective agonist at the N-methyl-D-aspartic acid (NMDA) subtype of excitatory amino acid receptors. Using the Ugi "four-component condensation" method, the two diastereomers (2R)- and (2S)-2-[3-(benzyloxy......) showed peak affinity for [3H]AMPA receptor sites (IC50 = 72 +/- 13 microM) and was shown to be a more potent inhibitor of [3H]CPP binding (IC50 = 3.7 +/- 1.5 microM) than (S)-AMAA (9) (IC50 = 61 +/- 6.4 microM). Neither enantiomer of AMAA affected [3H]kainic acid receptor binding significantly...

  3. Radiolabeled somatostatin receptor antagonists are preferable to agonists for in vivo peptide receptor targeting of tumors

    OpenAIRE

    Ginj, Mihaela; Zhang, Hanwen; Waser, Beatrice; Cescato, Renzo; Wild, Damian; Wang, Xuejuan; Erchegyi, Judit; Rivier, Jean; Mäcke, Helmut R.; Reubi, Jean Claude

    2006-01-01

    Targeting neuroendocrine tumors expressing somatostatin receptor subtypes (sst) with radiolabeled somatostatin agonists is an established diagnostic and therapeutic approach in oncology. While agonists readily internalize into tumor cells, permitting accumulation of radioactivity, radiolabeled antagonists do not, and they have not been considered for tumor targeting. The macrocyclic chelator 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA) was coupled to two potent somatostatin...

  4. Cognitive Impairment Induced by Delta9-tetrahydrocannabinol Occurs through Heteromers between Cannabinoid CB1 and Serotonin 5-HT2A Receptors.

    Directory of Open Access Journals (Sweden)

    Xavier Viñals

    2015-07-01

    Full Text Available Activation of cannabinoid CB1 receptors (CB1R by delta9-tetrahydrocannabinol (THC produces a variety of negative effects with major consequences in cannabis users that constitute important drawbacks for the use of cannabinoids as therapeutic agents. For this reason, there is a tremendous medical interest in harnessing the beneficial effects of THC. Behavioral studies carried out in mice lacking 5-HT2A receptors (5-HT2AR revealed a remarkable 5-HT2AR-dependent dissociation in the beneficial antinociceptive effects of THC and its detrimental amnesic properties. We found that specific effects of THC such as memory deficits, anxiolytic-like effects, and social interaction are under the control of 5-HT2AR, but its acute hypolocomotor, hypothermic, anxiogenic, and antinociceptive effects are not. In biochemical studies, we show that CB1R and 5-HT2AR form heteromers that are expressed and functionally active in specific brain regions involved in memory impairment. Remarkably, our functional data shows that costimulation of both receptors by agonists reduces cell signaling, antagonist binding to one receptor blocks signaling of the interacting receptor, and heteromer formation leads to a switch in G-protein coupling for 5-HT2AR from Gq to Gi proteins. Synthetic peptides with the sequence of transmembrane helices 5 and 6 of CB1R, fused to a cell-penetrating peptide, were able to disrupt receptor heteromerization in vivo, leading to a selective abrogation of memory impairments caused by exposure to THC. These data reveal a novel molecular mechanism for the functional interaction between CB1R and 5-HT2AR mediating cognitive impairment. CB1R-5-HT2AR heteromers are thus good targets to dissociate the cognitive deficits induced by THC from its beneficial antinociceptive properties.

  5. Negative Regulation of Leptin-induced Reactive Oxygen Species (ROS) Formation by Cannabinoid CB1 Receptor Activation in Hypothalamic Neurons.

    Science.gov (United States)

    Palomba, Letizia; Silvestri, Cristoforo; Imperatore, Roberta; Morello, Giovanna; Piscitelli, Fabiana; Martella, Andrea; Cristino, Luigia; Di Marzo, Vincenzo

    2015-05-29

    The adipocyte-derived, anorectic hormone leptin was recently shown to owe part of its regulatory effects on appetite-regulating hypothalamic neuropeptides to the elevation of reactive oxygen species (ROS) levels in arcuate nucleus (ARC) neurons. Leptin is also known to exert a negative regulation on hypothalamic endocannabinoid levels and hence on cannabinoid CB1 receptor activity. Here we investigated the possibility of a negative regulation by CB1 receptors of leptin-mediated ROS formation in the ARC. Through pharmacological and molecular biology experiments we report data showing that leptin-induced ROS accumulation is 1) blunted by arachidonyl-2'-chloroethylamide (ACEA) in a CB1-dependent manner in both the mouse hypothalamic cell line mHypoE-N41 and ARC neuron primary cultures, 2) likewise blocked by a peroxisome proliferator-activated receptor-γ (PPAR-γ) agonist, troglitazone, in a manner inhibited by T0070907, a PPAR-γ antagonist that also inhibited the ACEA effect on leptin, 3) blunted under conditions of increased endocannabinoid tone due to either pharmacological or genetic inhibition of endocannabinoid degradation in mHypoE-N41 and primary ARC neuronal cultures from MAGL(-/-) mice, respectively, and 4) associated with reduction of both PPAR-γ and catalase activity, which are reversed by both ACEA and troglitazone. We conclude that CB1 activation reverses leptin-induced ROS formation and hence possibly some of the ROS-mediated effects of the hormone by preventing PPAR-γ inhibition by leptin, with subsequent increase of catalase activity. This mechanism might underlie in part CB1 orexigenic actions under physiopathological conditions accompanied by elevated hypothalamic endocannabinoid levels.

  6. Regulation of transient receptor potential channels of melastatin type 8 (TRPM8): effect of cAMP, cannabinoid CB(1) receptors and endovanilloids.

    Science.gov (United States)

    De Petrocellis, Luciano; Starowicz, Katarzyna; Moriello, Aniello Schiano; Vivese, Marta; Orlando, Pierangelo; Di Marzo, Vincenzo

    2007-05-15

    The transient receptor potential channel of melastatin type 8 (TRPM8), which is gated by low (<25 degrees C) temperature and chemical compounds, is regulated by protein kinase C-mediated phosphorylation in a way opposite to that observed with the transient receptor potential channel of vanilloid type 1 (TRPV1), i.e. by being desensitized and not sensitized. As TRPV1 is sensitized also by protein kinase A (PKA)-mediated phosphorylation, we investigated the effect of two activators of the PKA pathway, 8-Br-cAMP and forskolin, on the activity of menthol and icilin at TRPM8 in HEK-293 cells stably overexpressing the channel (TRPM8-HEK-293 cells). We also studied the effect on TRPM8 of: (1) a series of compounds previously shown to activate or antagonize TRPV1, and (2) co-stimulation of transiently co-expressed cannabinoid CB(1) receptors. Both 8-Br-cAMP (100 microM) and forskolin (10 microM) right-shifted the dose-response curves for the TRPM8-mediated effect of icilin and menthol on intracellular Ca(2+). The inhibitory effects of 8-Br-cAMP and forskolin were attenuated by the selective PKA inhibitor Rp-cAMP-S. Stimulation of human CB(1) receptors transiently co-expressed in TRPM8-HEK-293 cells also inhibited TRPM8 response to icilin. Finally, some TRPV1 agonists and antagonists, but not iodinated antagonists, antagonized icilin- and much less so menthol-, induced TRPM8 activation. Importantly, the endovanilloids/endocannabinoids, anandamide and NADA, also antagonized TRPM8 at submicromolar concentrations. Although these findings need to be confirmed by experiments directly measuring TRPM8 activity in natively TRPM8-expressing cells, they support the notion that the same regulatory events have opposing actions on TRPM8 and TRPV1 receptors and identify anandamide and NADA as the first potential endogenous functional antagonists of TRPM8 channels.

  7. Participation of cannabinoid receptors in peripheral nociception induced by some NSAIDs

    Energy Technology Data Exchange (ETDEWEB)

    Silva, L.C.R.; Romero, T.R.L.; Guzzo, L.S.; Duarte, I.D.G. [Departamento de Farmacologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, MG (Brazil)

    2012-09-21

    Nonsteroidal anti-inflammatory drugs (NSAIDs) have been used extensively to control inflammatory pain. Several peripheral antinociceptive mechanisms have been described, such as opioid system and NO/cGMP/KATP pathway activation. There is evidence that the cannabinoid system can also contribute to the in vivo pharmacological effects of ibuprofen and indomethacin. However, there is no evidence of the involvement of the endocannabinoid system in the peripheral antinociception induced by NSAIDs. Thus, the aim of this study was to investigate the participation of the endocannabinoid system in the peripheral antinociceptive effect of NSAIDs. All experiments were performed on male Wistar rats (160-200 g; N = 4 per group). Hyperalgesia was induced by a subcutaneous intraplantar (ipl) injection of prostaglandin E{sub 2} (PGE{sub 2}, 2 µg/paw) in the rat's hindpaw and measured by the paw pressure test 3 h after injection. The weight in grams required to elicit a nociceptive response, paw flexion, was determined as the nociceptive threshold. The hyperalgesia was calculated as the difference between the measurements made before and after PGE{sub 2}, which induced hyperalgesia (mean = 83.3 ± 4.505 g). AM-251 (80 µg/paw) and AM-630 (100 µg/paw) were used as CB{sub 1} and CB{sub 2} cannabinoid receptor antagonists, respectively. Ipl injection of 40 µg dipyrone (mean = 5.825 ± 2.842 g), 20 µg diclofenac (mean = 4.825 ± 3.850 g) and 40 µg indomethacin (mean = 6.650 ± 3.611 g) elicited a local peripheral antinociceptive effect. This effect was not antagonized by ipl CB{sub 1} cannabinoid antagonist to dipyrone (mean = 5.00 ± 0.9815 g), diclofenac (mean = 2.50 ± 0.8337 g) and indomethacin (mean = 6.650 ± 4.069 g) or CB{sub 2} cannabinoid antagonist to dipyrone (mean = 1.050 ± 6.436 g), diclofenac (mean = 6.675 ± 1.368 g) and indomethacin (mean = 2.85 ± 5.01 g). Thus, cannabinoid receptors do not seem to be involved in the peripheral antinociceptive mechanism of

  8. Participation of cannabinoid receptors in peripheral nociception induced by some NSAIDs

    Directory of Open Access Journals (Sweden)

    L.C.R. Silva

    2012-12-01

    Full Text Available Nonsteroidal anti-inflammatory drugs (NSAIDs have been used extensively to control inflammatory pain. Several peripheral antinociceptive mechanisms have been described, such as opioid system and NO/cGMP/KATP pathway activation. There is evidence that the cannabinoid system can also contribute to the in vivo pharmacological effects of ibuprofen and indomethacin. However, there is no evidence of the involvement of the endocannabinoid system in the peripheral antinociception induced by NSAIDs. Thus, the aim of this study was to investigate the participation of the endocannabinoid system in the peripheral antinociceptive effect of NSAIDs. All experiments were performed on male Wistar rats (160-200 g; N = 4 per group. Hyperalgesia was induced by a subcutaneous intraplantar (ipl injection of prostaglandin E2 (PGE2, 2 μg/paw in the rat’s hindpaw and measured by the paw pressure test 3 h after injection. The weight in grams required to elicit a nociceptive response, paw flexion, was determined as the nociceptive threshold. The hyperalgesia was calculated as the difference between the measurements made before and after PGE2, which induced hyperalgesia (mean = 83.3 ± 4.505 g. AM-251 (80 μg/paw and AM-630 (100 μg/paw were used as CB1 and CB2 cannabinoid receptor antagonists, respectively. Ipl injection of 40 μg dipyrone (mean = 5.825 ± 2.842 g, 20 μg diclofenac (mean = 4.825 ± 3.850 g and 40 μg indomethacin (mean = 6.650 ± 3.611 g elicited a local peripheral antinociceptive effect. This effect was not antagonized by ipl CB1 cannabinoid antagonist to dipyrone (mean = 5.00 ± 0.9815 g, diclofenac (mean = 2.50 ± 0.8337 g and indomethacin (mean = 6.650 ± 4.069 g or CB2 cannabinoid antagonist to dipyrone (mean = 1.050 ± 6.436 g, diclofenac (mean = 6.675 ± 1.368 g and indomethacin (mean = 2.85 ± 5.01 g. Thus, cannabinoid receptors do not seem to be involved in the peripheral antinociceptive mechanism of the NSAIDs dipyrone, diclofenac and

  9. Cannabinoid receptor 2 expression modulates Gβ(1)γ(2) protein interaction with the activator of G protein signalling 2/dynein light chain protein Tctex-1.

    Science.gov (United States)

    Nagler, Marina; Palkowitsch, Lysann; Rading, Sebastian; Moepps, Barbara; Karsak, Meliha

    2016-01-01

    The activator of G protein signalling AGS2 (Tctex-1) forms protein complexes with Gβγ, and controls cell proliferation by regulating cell cycle progression. A direct interaction of Tctex-1 with various G protein-coupled receptors has been reported. Since the carboxyl terminal portion of CB2 carries a putative Tctex-1 binding motif, we investigated the potential interplay of CB2 and Tctex-1 in the absence and presence of Gβγ. The supposed interaction of cannabinoid receptor CB2 with Tctex-1 and the influence of CB2 on the formation of Tctex-1-Gβγ-complexes were studied by co- and/or immunoprecipitation experiments in transiently transfected HEK293 cells. The analysis on Tctex-1 protein was performed in the absence and presence of the ligands JWH 133, 2-AG, and AM 630, the protein biosynthesis inhibitor cycloheximide or the protein degradation blockers MG132, NH4Cl/leupeptin or bafilomycin. Our results show that CB2 neither directly nor indirectly via Gβγ interacts with Tctex-1, but competes with Tctex-1 in binding to Gβγ. The Tctex-1-Gβγ protein interaction was disrupted by CB2 receptor expression resulting in a release of Tctex-1 from the complex, and its degradation by the proteasome and partly by lysosomes. The decrease in Tctex-1 protein levels is induced by CB2 expression "dose-dependently" and is independent of stimulation by agonist or blocking by an inverse agonist treatment. The results suggest that CB2 receptor expression independent of its activation by agonists is sufficient to competitively disrupt Gβγ-Tctex-1 complexes, and to initiate Tctex-1 degradation. These findings implicate that CB2 receptor expression modifies the stability of intracellular protein complexes by a non-canonical pathway.

  10. Activation of type 2 cannabinoid receptors (CB2R) promotes fatty acid oxidation through the SIRT1/PGC-1α pathway

    Energy Technology Data Exchange (ETDEWEB)

    Zheng, Xuqin [Department of Endocrinology, First Affiliated Hospital, Nanjing Medical University, Nanjing, Jiangsu Province 210029 (China); Sun, Tao [Department of Neurology, Jinling Hospital, Nanjing University School of Medicine, Nanjing, Jiangsu Province 210002 (China); Wang, Xiaodong, E-mail: xdwang666@hotmail.com [Department of Endocrinology, First Affiliated Hospital, Nanjing Medical University, Nanjing, Jiangsu Province 210029 (China)

    2013-07-05

    Highlights: •TC, a CB2R specific agonist, stimulates SIRT1 activity by PKA/CREB pathway. •TC promotes PGC-1α transcriptional activity by increasing its deacetylation. •TC increases the expression of genes linked to FAO and promotes the rate of FAO. •The effects of TC in FAO are dependent on CB2R. •Suggesting CB2R as a target to treat diseases with lipid dysregulation. -- Abstract: Abnormal fatty acid oxidation has been associated with obesity and type 2 diabetes. At the transcriptional level, peroxisome proliferator-activated receptor-gamma coactivator 1α (PGC-1α) has been reported to strongly increase the ability of hormone nuclear receptors PPARα and ERRα to drive transcription of fatty acid oxidation enzymes. In this study, we report that a specific agonist of the type 2 cannabinoid receptor (CB2R) can lead to fatty acid oxidation through the PGC-1α pathway. We have found that CB2R is expressed in differentiated C2C12 myotubes, and that use of the specific agonist trans-caryophyllene (TC) stimulates sirtuin 1 (SIRT1) deacetylase activity by increasing the phosphorylation of cAMP response element-binding protein (CREB), thus leading to increased levels of PGC-1α deacetylation. This use of TC treatment increases the expression of genes linked to the fatty acid oxidation pathway in a SIRT1/PGC-1α-dependent mechanism and also drastically accelerates the rate of complete fatty acid oxidation in C2C12 myotubes, neither of which occur when CB2R mRNA is knocked down using siRNA. These results reveal that activation of CB2R by a selective agonist promotes lipid oxidation through a signaling/transcriptional pathway. Our findings imply that pharmacological manipulation of CB2R may provide therapeutic possibilities to treat metabolic diseases associated with lipid dysregulation.

  11. Novel Method for Synthesis of Diarylpyrazole Derivatives as Cannabinoid CB1 Receptor Antagonists

    Institute of Scientific and Technical Information of China (English)

    WU Ying-qiu; ZHENG Guo-jun; WANG Ya-ping; WANG Xiang-jing; XIANG Wen-sheng

    2011-01-01

    A novel and efficient method was developed for the synthesis of diarylpyrazole derivatives as cannabinoid CB1 receptor antagonist via four step reactions. The key step was the synthesis of a diarylpyrazole skeleton, which involved initial condensation of the sodium salt of compound 12 with diazonium compounds, and further cyclization by heating at reflux in acetic acid. Eight diarylpyrazole derivatives and nine new synthesized compounds were cha racterized by 1H NMRy IR, MS, and elemental analysis. The reaction conditions were mild and the overall yields of the target compounds ranged from 26% to 44%.

  12. CB1 cannabinoid receptor enrichment in the ependymal region of the adult human spinal cord.

    Science.gov (United States)

    Paniagua-Torija, Beatriz; Arevalo-Martin, Angel; Ferrer, Isidro; Molina-Holgado, Eduardo; Garcia-Ovejero, Daniel

    2015-12-04

    Cannabinoids are involved in the regulation of neural stem cell biology and their receptors are expressed in the neurogenic niches of adult rodents. In the spinal cord of rats and mice, neural stem cells can be found in the ependymal region, surrounding the central canal, but there is evidence that this region is largely different in adult humans: lacks a patent canal and presents perivascular pseudorosettes, typically found in low grade ependymomas. Using Laser Capture Microdissection, Taqman gene expression assays and immunohistochemistry, we have studied the expression of endocannabinoid system components (receptors and enzymes) at the human spinal cord ependymal region. We observe that ependymal region is enriched in CB1 cannabinoid receptor, due to high CB1 expression in GFAP+ astrocytic domains. However, in human spinal cord levels that retain central canal patency we found ependymal cells with high CB1 expression, equivalent to the CB1(HIGH) cell subpopulation described in rodents. Our results support the existence of ependymal CB1(HIGH) cells across species, and may encourage further studies on this subpopulation, although only in cases when central canal is patent. In the adult human ependyma, which usually shows central canal absence, CB1 may play a different role by modulating astrocyte functions.

  13. Targeting cannabinoid receptor CB(2) in cardiovascular disorders: promises and controversies.

    Science.gov (United States)

    Steffens, Sabine; Pacher, Pál

    2012-09-01

    Cardiovascular disease is the leading cause of death and disability worldwide, which can be largely attributed to atherosclerosis, a chronic inflammation of the arteries characterized by lesions containing immune and smooth muscle cells, lipids and extracellular matrix. In recent years, the lipid endocannabinoid system has emerged as a new therapeutic target in variety of disorders associated with inflammation and tissue injury, including those of the cardiovascular system. The discovery that Δ-9-tetrahydrocannabinol (Δ9-THC), the main active constituent of marijuana, inhibited atherosclerotic plaque progression via a cannabinoid 2 (CB(2) ) receptor-dependent anti-inflammatory mechanism, and that certain natural and synthetic cannabinoid ligands could modulate the myocardial or cerebral ischaemia-reperfusion-induced tissue damage, have stimulated impetus for a growing number of studies investigating the implication of CB(2) receptors in atherosclerosis, restenosis, stroke, myocardial infarction and heart failure. The aim of this review is to update on recent findings and controversies on the role of CB(2) receptors in cardiovascular disease. Particular emphasis will be placed on novel insights in the potential cellular targets of CB(2) stimulation in cardiovascular system (e.g. endothelial and vascular smooth muscle cells, cardiomyocytes, infiltrating and/or resident monocytes/macrophages and leukocytes, etc.), their interplay and intracellular signalling mechanisms identified, as well as on experimental and clinical studies. PMID:22612332

  14. Cannabinoids on the Brain

    Directory of Open Access Journals (Sweden)

    Andrew J. Irving

    2002-01-01

    Full Text Available Cannabis has a long history of consumption both for recreational and medicinal uses. Recently there have been significant advances in our understanding of how cannabis and related compounds (cannabinoids affect the brain and this review addresses the current state of knowledge of these effects. Cannabinoids act primarily via two types of receptor, CB1 and CB2, with CB1 receptors mediating most of the central actions of cannabinoids. The presence of a new type of brain cannabinoid receptor is also indicated. Important advances have been made in our understanding of cannabinoid receptor signaling pathways, their modulation of synaptic transmission and plasticity, the cellular targets of cannabinoids in different central nervous system (CNS regions and, in particular, the role of the endogenous brain cannabinoid (endocannabinoid system. Cannabinoids have widespread actions in the brain: in the hippocampus they influence learning and memory; in the basal ganglia they modulate locomotor activity and reward pathways; in the hypothalamus they have a role in the control of appetite. Cannabinoids may also be protective against neurodegeneration and brain damage and exhibit anticonvulsant activity. Some of the analgesic effects of cannabinoids also appear to involve sites within the brain. These advances in our understanding of the actions of cannabinoids and the brain endocannabinoid system have led to important new insights into neuronal function which are likely to result in the development of new therapeutic strategies for the treatment of a number of key CNS disorders.

  15. Upregulation of Cannabinoid Type 1 Receptors in Dopamine D2 Receptor Knockout Mice Is Reversed by Chronic Forced Ethanol Consumption

    Energy Technology Data Exchange (ETDEWEB)

    Thanos, P.K.; Wang, G.; Thanos, P.K.; Gopez, V.; Delis, F.; Michaelides, M.; Grand, D.K.; Wang, G.-J.; Kunos, G.; Volkow, N.D.

    2011-01-01

    The anatomical proximity of the cannabinoid type 1 (CNR1/CB1R) and the dopamine D2 receptors (DRD2), their ability to form CB1R-DRD2 heteromers, their opposing roles in locomotion, and their involvement in ethanol's reinforcing and addictive properties prompted us to study the levels and distribution of CB1R after chronic ethanol intake, in the presence and absence of DRD2. We monitored the drinking patterns and locomotor activity of Drd2+/+ and Drd2-/- mice consuming either water or a 20% (v/v) ethanol solution (forced ethanol intake) for 6 months and used the selective CB1 receptor antagonist [{sup 3}H]SR141716A to quantify CB1R levels in different brain regions with in vitro receptor autoradiography. We found that the lack of DRD2 leads to a marked upregulation (approximately 2-fold increase) of CB1R in the cerebral cortex, the caudate-putamen, and the nucleus accumbens, which was reversed by chronic ethanol intake. The results suggest that DRD2-mediated dopaminergic neurotransmission and chronic ethanol intake exert an inhibitory effect on cannabinoid receptor expression in cortical and striatal regions implicated in the reinforcing and addictive properties of ethanol.

  16. Identification of naphthoylindoles acting on cannabinoid receptors based on their fragmentation patterns under ESI-QTOFMS.

    Science.gov (United States)

    Sekuła, Karolina; Zuba, Dariusz; Stanaszek, Roman

    2012-05-01

    'Herbal highs' have been advertised as legal and natural substitutes to cannabis, but a detailed examination of these products has revealed that the herbal matrix is laced with synthetic substances that mimic the effects of marijuana. Producers select the ingredients based on the results of scientific studies on the affinities of different chemicals to cannabinoid receptors. Naphthoylindoles have turned out to be the most popular class of substances identified in the products. Legal actions taken in order to tackle the problem of uncontrolled access to one substance have usually resulted in the marketing of derivatives or analogues. In the study, the mass spectral behavior of twelve synthetic cannabinoids from the naphthoylindole family under electrospray ionization (ESI) was investigated. LC-QTOFMS experiments were performed in three modes (low fragmentor voltage, high fragmentor voltage with/without collision energy), and they enabled the identification of protonated molecules and main ions. A general fragmentation pattern under this ionization method was proposed, and mechanisms of ion formation were discussed. The developed procedure allowed the determination of substituent groups of the core naphthoylindole structure and distinction between positional isomers. The obtained results were used for the prediction of the ESI-MS spectra for many naphthoylindoles with a high affinity to cannabinoid receptors. Similarities and differences between ESI-MS and electron impact-MS spectra of naphthoylindoles were discussed. The developed identification process was presented on an example of an analysis of an unknown herbal material, in which JWH-007 was finally identified. Knowledge of the fragmentation mechanisms of naphthoylindoles could also be used by other researchers for identification of unknown substances in this chemical family. PMID:22576877

  17. Evaluation of the abuse potential of AM281, a new synthetic cannabinoid CB1 receptor antagonist.

    Science.gov (United States)

    Botanas, Chrislean Jun; de la Peña, June Bryan; Dela Pena, Irene Joy; Tampus, Reinholdgher; Kim, Hee Jin; Yoon, Seong Shoon; Seo, Joung-Wook; Jeong, Eun Ju; Cheong, Jae Hoon

    2015-11-01

    AM281 (1-(2,4-dichlorophenyl)-5-(4-iodophenyl)-4-methyl-N-4-morpholinyl-1H-pyrazole-3-carboxamide) is a new synthetic cannabinoid CB1 receptor antagonist. Similar to other cannabinoid antagonists, AM281 has been suggested to have therapeutic indications. However, recent reports have suggested that cannabinoid CB1 receptor antagonists may share similar behavioral effects with other drugs of abuse such as cocaine and amphetamine. These reports cast doubts on the safety profile of AM281. Thus, in the present study we evaluated the abuse potential (rewarding and reinforcing effects) of AM281 through two of the most widely used animal models for assessing the abuse potential of drugs: the conditioned place preference (CPP) and self-administration (SA) tests. Experiments were performed in Sprague-Dawley rats in various dosages [CPP (0.1, 0.5 or 2.5mg/kg), SA (0.005, 0.025 or 0.1mg/kg/infusion)]. We also delved into the consequences of repeated drug exposure on the subsequent response to the drug. Thus, parallel experiments were carried out in rats pretreated with AM281 for 7 or 14 days. Our findings indicated that AM281, at any dose, did not induce CPP and SA in drug-naïve rats. Interestingly, significant CPP (0.5mg/kg of AM281), but not SA, was observed in 14 days pretreated rats. These observations suggest that AM281 per se has no or minimal rewarding and reinforcing properties, but alterations in neuronal functions and behavior due to repeated AM281 exposure may contribute in part to the abuse potential of this drug. In view of this finding, we advocate the careful use, monitoring, and dispensation of AM281.

  18. Endocannabinoids Anandamide and Its Cannabinoid Receptors in Liver Fibrosis after Murine Schistosomiasis

    Institute of Scientific and Technical Information of China (English)

    Hongyan LIU; Xiao GAO; Ruixian DUAN; Qiao YANG; Yaowen ZHANG; Yongwei CHENG; Yan GUO; Wangxian TANG

    2009-01-01

    This study examined endogenous cannabinoid (ECB)-anandamide (AEA) and its can-nabinoid receptors (CBR) in mice liver with the development of schistosomajaponicum.Mice were infected with schistosoma by means of pasting the cercaria onto their abdomens.Liver fibrosis was pathologically confirmed nine weeks after the infection.High performance liquid chromatography (HPLC) was employed to determine the concentration of AEA in the plasma of mice.Immunofluorescence was used to detect the expression of CBR 1 and CBR2 in liver tissue.Morphological examination showed typical pathological changes,with worm tubercles of schistosoma deposited in the liver tissue,fibrosis around the worm tubercles and infiltration or soakage ofinfiammatory cells.Also,CBRI and CBR2 were present in hepatocytes and hepatic sinusoids of the two groups,but they were obviously enhanced in the schistosoma-infected mice.However,the average optical density of CBR1 in the negative control and fibrosis group was 13.28±7.32 and 30.55±7.78,and CBR2 were 28.13±6.42 and 52.29±4.24 (P<0.05).The levels of AEA in the fibrosis group were significantly increased as compared with those of the control group.The concentrations of AEA were (0.37±0.07) and (5.67±1.34) ng/mL (P<0.05).It is concluded that the expression of endocannabinoids AEA and its cannabinoid receptor CBR were significantly increased in schistosoma-infected mice.Endogenous endocannabinoids may be involved in the development of schistosoma-induced liver fibrosis.

  19. Cannabinoid-1 receptor antagonists in type-2 diabetes.

    Science.gov (United States)

    Scheen, André J

    2007-12-01

    Type-2 diabetes is closely related to abdominal obesity and is generally associated with other cardiometabolic risk factors, resulting in a risk of major cardiovascular disease. Several animal and human observations suggest that the endocannabinoid system is over-active in the presence of abdominal obesity and/or diabetes. Both central and peripheral endocannabinoid actions, via the activation of CB1 receptors, promote weight gain and associated metabolic changes. Rimonabant, the first selective CB(1) receptor blocker in clinical use, has been shown to reduce body weight, waist circumference, triglycerides, blood pressure, insulin resistance index and C-reactive protein levels, and to increase high-density lipoprotein (HDL) cholesterol and adiponectin concentrations in both non-diabetic and diabetic overweight/obese patients. In addition, a 0.5-0.7% reduction in HbA1c levels was observed in metformin- or sulphonylurea-treated patients with type-2 diabetes and in drug-naïve diabetic patients. Almost half of the metabolic changes, including HbA1c reduction, could not be explained by weight loss, suggesting that there are direct peripheral effects. Rimonabant was generally well-tolerated, and the safety profile was similar in diabetic and non-diabetic patients, with a higher incidence of depressed mood disorders, nausea and dizziness. In conclusion, the potential role of rimonabant in overweight/obese patients with type-2 diabetes and at high risk of cardiovascular disease deserves much consideration.

  20. Binding Mode of Insulin Receptor and Agonist Peptide

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Insulin is a protein hormone secreted by pancreatic β cells. One of its main functions is to keep the balance of glucose inside the body by regulating the absorption and metabolism of glucose in the periphery tissue, as well as the production and storage of hepatic glycogen. The insulin receptor is a transmembrane glycoprotein in which two α subunits with a molecular weight of 135 kD and twoβ subunits with a molecular weight of 95 kD are joined by a disulfide bond to form a β-α-α-β structure. The extracellular α subunit, especially, its three domains near the N-terminal are partially responsible for signal transduction or ligand-binding, as indicated by the experiments. The extracellular α subunits are involved in binding the ligands. The experimental results indicate that the three domains of the N-terminal of the α subunits are the main determinative parts of the insulin receptor to bind the insulin or mimetic peptide.We employed the extracellular domain (PDBID: 1IGR) of the insulin-like growth factor-1 receptor (IGF-1 R ) as the template to simulate and optimize the spatial structures of the three domains in the extracellular domain of the insulin receptor, which includes 468 residues. The work was accomplished by making use of the homology program in the Insight Ⅱ package on an Origin3800 server. The docking calculations of the insulin receptor obtained by homology with hexapeptides were carried out by means of the program Affinity. The analysis indicated that there were hydrogen bonding, and electrostatic and hydrophobic effects in the docking complex of the insulin receptor with hexapeptides.Moreover, we described the spatial orientation of a mimetic peptide with agonist activity in the docking complex. We obtained a rough model of binding of DLAPSQ or STIVYS with the insulin receptor, which provides the powerful theoretical support for designing the minimal insulin mimetic peptide with agonist activity, making it possible to develop oral small

  1. Cannabinoid Type-1 Receptor Gene Polymorphisms Are Associated with Central Obesity in a Southern Brazilian Population

    Directory of Open Access Journals (Sweden)

    Janaína P. Jaeger

    2008-01-01

    Full Text Available The CB1 cannabinoid receptor and its endogenous ligands, the endocannabinoids, are involved in energy balance control, stimulating appetite and increasing body weight in wasting syndromes. Different studies have investigated the relationship between polymorphisms of the cannabinoid receptor 1 (CNR1 gene and obesity with conflicting results. In the present study, we investigated the 1359G/A (rs1049353, 3813A/G (rs12720071 and 4895A/G (rs806368 polymorphisms in the CNR1 gene in a Brazilian population of European descent. To verify the association between these variants and obesity-related traits in this population, 756 individuals were genotyped by PCR-RFLP methods. The 4895G allele was associated with waist to hip ratio (WHR (P = 0.014; P = 0.042 after Bonferroni correction. An additive effect with the GAA haplotype was associated with WHR (P = 0.028, although this statistical significance disappeared after Bonferroni correction (P = 0.084. No significant association was observed between the genotypes of the 1359G/A and 3813A/G polymorphisms and any of the quantitative variables investigated. Our findings suggest that CNR1 gene polymorphism is associated with central obesity in this Brazilian population of European ancestry.

  2. Blockade of cannabinoid 1 receptor improves GLP-1R mediated insulin secretion in mice.

    Science.gov (United States)

    González-Mariscal, Isabel; Krzysik-Walker, Susan M; Kim, Wook; Rouse, Michael; Egan, Josephine M

    2016-03-01

    The cannabinoid 1 receptor (CB1) is an important regulator of energy metabolism. Reports of in vivo and in vitro studies give conflicting results regarding its role in insulin secretion, possibly due to circulatory factors, such as incretins. We hypothesized that this receptor may be a regulator of the entero-insular axis. We found that despite lower food consumption and lower body weight postprandial GLP-1 plasma concentrations were increased in CB1(-/-) mice compared to CB1(+/+) mice administered a standard diet or high fat/sugar diet. Upon exogenous GLP-1 treatment, CB1(-/-) mice had increased glucose-stimulated insulin secretion. In mouse insulinoma cells, cannabinoids reduced GLP-1R-mediated intracellular cAMP accumulation and subsequent insulin secretion. Importantly, such effects were also evident in human islets, and were prevented by pharmacologic blockade of CB1. Collectively, these findings suggest a novel mechanism in which endocannabinoids are negative modulators of incretin-mediated insulin secretion. PMID:26724516

  3. Peripheral and central CB1 cannabinoid receptors control stress-induced impairment of memory consolidation.

    Science.gov (United States)

    Busquets-Garcia, Arnau; Gomis-González, Maria; Srivastava, Raj Kamal; Cutando, Laura; Ortega-Alvaro, Antonio; Ruehle, Sabine; Remmers, Floortje; Bindila, Laura; Bellocchio, Luigi; Marsicano, Giovanni; Lutz, Beat; Maldonado, Rafael; Ozaita, Andrés

    2016-08-30

    Stressful events can generate emotional memories linked to the traumatic incident, but they also can impair the formation of nonemotional memories. Although the impact of stress on emotional memories is well studied, much less is known about the influence of the emotional state on the formation of nonemotional memories. We used the novel object-recognition task as a model of nonemotional memory in mice to investigate the underlying mechanism of the deleterious effect of stress on memory consolidation. Systemic, hippocampal, and peripheral blockade of cannabinoid type-1 (CB1) receptors abolished the stress-induced memory impairment. Genetic deletion and rescue of CB1 receptors in specific cell types revealed that the CB1 receptor population specifically in dopamine β-hydroxylase (DBH)-expressing cells is both necessary and sufficient for stress-induced impairment of memory consolidation, but CB1 receptors present in other neuronal populations are not involved. Strikingly, pharmacological manipulations in mice expressing CB1 receptors exclusively in DBH(+) cells revealed that both hippocampal and peripheral receptors mediate the impact of stress on memory consolidation. Thus, CB1 receptors on adrenergic and noradrenergic cells provide previously unrecognized cross-talk between central and peripheral mechanisms in the stress-dependent regulation of nonemotional memory consolidation, suggesting new potential avenues for the treatment of cognitive aspects on stress-related disorders. PMID:27528659

  4. Therapeutic applications of TRAIL receptor agonists in cancer and beyond.

    Science.gov (United States)

    Amarante-Mendes, Gustavo P; Griffith, Thomas S

    2015-11-01

    TRAIL/Apo-2L is a member of the TNF superfamily first described as an apoptosis-inducing cytokine in 1995. Similar to TNF and Fas ligand, TRAIL induces apoptosis in caspase-dependent manner following TRAIL death receptor trimerization. Because tumor cells were shown to be particularly sensitive to this cytokine while normal cells/tissues proved to be resistant along with being able to synthesize and release TRAIL, it was rapidly appreciated that TRAIL likely served as one of our major physiologic weapons against cancer. In line with this, a number of research laboratories and pharmaceutical companies have attempted to exploit the ability of TRAIL to kill cancer cells by developing recombinant forms of TRAIL or TRAIL receptor agonists (e.g., receptor-specific mAb) for therapeutic purposes. In this review article we will describe the biochemical pathways used by TRAIL to induce different cell death programs. We will also summarize the clinical trials related to this pathway and discuss possible novel uses of TRAIL-related therapies. In recent years, the physiological importance of TRAIL has expanded beyond being a tumoricidal molecule to one critical for a number of clinical settings - ranging from infectious disease and autoimmunity to cardiovascular anomalies. We will also highlight some of these conditions where modulation of the TRAIL/TRAIL receptor system may be targeted in the future. PMID:26343199

  5. Human orexin/hypocretin receptors form constitutive homo- and heteromeric complexes with each other and with human CB1 cannabinoid receptors

    International Nuclear Information System (INIS)

    Highlights: • OX1 and OX2 orexin and CB1 cannabinoid receptor dimerization was investigated. • Bioluminescence resonance energy transfer method was used. • All receptors readily formed constitutive homo- and heteromeric complexes. - Abstract: Human OX1 orexin receptors have been shown to homodimerize and they have also been suggested to heterodimerize with CB1 cannabinoid receptors. The latter has been suggested to be important for orexin receptor responses and trafficking. In this study, we wanted to assess the ability of the other combinations of receptors to also form similar complexes. Vectors for expression of human OX1, OX2 and CB1 receptors, C-terminally fused with either Renilla luciferase or GFP2 green fluorescent protein variant, were generated. The constructs were transiently expressed in Chinese hamster ovary cells, and constitutive dimerization between the receptors was assessed by bioluminescence energy transfer (BRET). Orexin receptor subtypes readily formed homo- and hetero(di)mers, as suggested by significant BRET signals. CB1 receptors formed homodimers, and they also heterodimerized with both orexin receptors. Interestingly, BRET efficiency was higher for homodimers than for almost all heterodimers. This is likely to be due to the geometry of the interaction; the putatively symmetric dimers may place the C-termini in a more suitable orientation in homomers. Fusion of luciferase to an orexin receptor and GFP2 to CB1 produced more effective BRET than the opposite fusions, also suggesting differences in geometry. Similar was seen for the OX1–OX2 interaction. In conclusion, orexin receptors have a significant propensity to make homo- and heterodi-/oligomeric complexes. However, it is unclear whether this affects their signaling. As orexin receptors efficiently signal via endocannabinoid production to CB1 receptors, dimerization could be an effective way of forming signal complexes with optimal cannabinoid concentrations available for

  6. Müller cells express the cannabinoid CB2 receptor in the vervet monkey retina

    DEFF Research Database (Denmark)

    Bouskila, Joseph; Javadi, Pasha; Casanova, Christian;

    2013-01-01

    The presence of the cannabinoid receptor type 1 (CB1R) has been largely documented in the rodent and primate retinae in recent years. There is, however, some controversy concerning the presence of the CB2 receptor (CB2R) within the central nervous system. Only recently, CB2R has been found...... in the rodent retina, but its presence in the primate retina has not yet been demonstrated. The aim of this study was twofold: 1) to characterize the distribution patterns of CB2R in the monkey retina and compare this distribution with that previously reported for CB1R and 2) to resolve the controversy...... on the presence of CB2R in the neural component of the retina. We therefore thoroughly examined the cellular localization of CB2R in the vervet monkey (Chlorocebus sabeus) retina, using confocal microscopy. Our results demonstrate that CB2R, like CB1R, is present throughout the retinal layers, but with striking...

  7. Feeding Induced by Cannabinoids Is Mediated Independently of the Melanocortin System

    OpenAIRE

    Sinnayah, Puspha; Jobst, Erin E.; Rathner, Joseph A.; Caldera-Siu, Angela D.; Tonelli-Lemos, Luciana; Eusterbrock, Aaron J.; Enriori, Pablo J.; Pothos, Emmanuel N.; Grove, Kevin L.; Cowley, Michael A.

    2008-01-01

    Background Cannabinoids, the active components of marijuana, stimulate appetite, and cannabinoid receptor-1 (CB1-R) antagonists suppress appetite and promote weight loss. Little is known about how CB1-R antagonists affect the central neurocircuitry, specifically the melanocortin system that regulates energy balance. Methodology/Principal Findings Here, we show that peripherally administered CB1-R antagonist (AM251) or agonist equally suppressed or stimulated feeding respectively in Ay , which...

  8. The cannabinoid CB₂ receptor-selective phytocannabinoid beta-caryophyllene exerts analgesic effects in mouse models of inflammatory and neuropathic pain.

    Science.gov (United States)

    Klauke, A-L; Racz, I; Pradier, B; Markert, A; Zimmer, A M; Gertsch, J; Zimmer, A

    2014-04-01

    The widespread plant volatile beta-caryophyllene (BCP) was recently identified as a natural selective agonist of the peripherally expressed cannabinoid receptor 2 (CB₂). It is found in relatively high concentrations in many spices and food plants. A number of studies have shown that CB₂ is critically involved in the modulation of inflammatory and neuropathic pain responses. In this study, we have investigated the analgesic effects of BCP in animal models of inflammatory and neuropathic pain. We demonstrate that orally administered BCP reduced inflammatory (late phase) pain responses in the formalin test in a CB₂ receptor-dependent manner, while it had no effect on acute (early phase) responses. In a neuropathic pain model the chronic oral administration of BCP attenuated thermal hyperalgesia and mechanical allodynia, and reduced spinal neuroinflammation. Importantly, we found no signs of tolerance to the anti-hyperalgesic effects of BCP after prolonged treatment. Oral BCP was more effective than the subcutaneously injected synthetic CB₂ agonist JWH-133. Thus, the natural plant product BCP may be highly effective in the treatment of long lasting, debilitating pain states. Our results have important implications for the role of dietary factors in the development and modulation of chronic pain conditions.

  9. Effect of the cannabinoid receptor-1 antagonist rimonabant on inflammation in mice with diet-induced obesity

    Science.gov (United States)

    We studied whether cannabinoid receptor (CB1) blockade with rimonabant has an anti-inflammatory effect in obese mice, and whether this effect depends on weight loss and/or diet consumption. High-fat diet (HFD)-induced obese mice were treated orally with rimonabant (HFD-R) or vehicle (HFD-V) for 4 we...

  10. The GABAA receptor agonist THIP is neuroprotective in organotypic hippocampal slice cultures

    DEFF Research Database (Denmark)

    Kristensen, Bjarne Winther; Noraberg, Jens; Zimmer, Jens

    2003-01-01

    The potential neuroprotective effects of the GABA(A) receptor agonists THIP (4,5,6,7-tetrahydroisoxazolo[5,4-c]pyridin-3-ol) and muscimol, and the selective GluR5 kainate receptor agonist ATPA ((RS)-2-amino-3-(3-hydroxy-5-tert-butylisoxazol-4-yl)propanoic acid), which activates GABAergic interneu...

  11. Synthesis and Biological Evaluation of Thiophene-Based Cannabinoid Receptor Type 2 Radiotracers for PET Imaging

    Directory of Open Access Journals (Sweden)

    Ahmed Haider

    2016-07-01

    Full Text Available Over the past two decades, our understanding of the endocannabinoid system has greatly improved due to the wealth of results obtained from exploratory studies. Currently, two cannabinoid receptor subtypes have been well characterized. The cannabinoid receptor type 1 (CB1 is widely expressed in the central nervous system, while the levels of the cannabinoid receptor type 2 (CB2 in the brain and spinal cord of healthy individuals are relatively low. However, recent studies demonstrated a CB2 upregulation on activated microglia upon neuroinflammation, an indicator of neurodegeneration. Our research group aims to develop a suitable positron emission tomography (PET tracer to visualize the CB2 receptor in patients suffering from neurodegenerative diseases. Herein we report two novel thiophene-based 11C-labeled PET ligands designated [11C]AAT-015 and [11C]AAT-778. The reference compounds were synthesized using Gewald reaction conditions to obtain the aminothiophene intermediates, followed by amide formation. Saponification of the esters provided their corresponding precursors. Binding affinity studies revealed Ki values of 3.3 ± 0.5 nM (CB2 and 1.0 ± 0.2 µM (CB1 for AAT-015. AAT-778 showed similar Ki values of 4.3 ± 0.7 nM (CB2 and 1.1 ± 0.1 µM (CB1. Radiosynthesis was carried out under basic conditions using [11C]iodomethane as methylating agent. After semi-preparative HPLC purification both radiolabeled compounds were obtained in 99% radiochemical purity and the radiochemical yields ranged from 12 to 37%. Specific activity was between 96 - 449 GBq/µmol for both tracers. In order to demonstrate CB2 specificity of [11C]AAT-015 and [11C]AAT-778, we carried out autoradiography studies using CB2-positive mouse/rat spleen tissues. The obtained results revealed unspecific binding in spleen tissue that was not blocked by an excess of CB2-specific ligand GW402833. For in vivo analysis, [11C]AAT-015 was administered to healthy rats via tail

  12. Synthesis and Biological Evaluation of Thiophene-Based Cannabinoid Receptor Type 2 Radiotracers for PET Imaging

    Science.gov (United States)

    Haider, Ahmed; Müller Herde, Adrienne; Slavik, Roger; Weber, Markus; Mugnaini, Claudia; Ligresti, Alessia; Schibli, Roger; Mu, Linjing; Mensah Ametamey, Simon

    2016-01-01

    Over the past two decades, our understanding of the endocannabinoid system has greatly improved due to the wealth of results obtained from exploratory studies. Currently, two cannabinoid receptor subtypes have been well-characterized. The cannabinoid receptor type 1 (CB1) is widely expressed in the central nervous system, while the levels of the cannabinoid receptor type 2 (CB2) in the brain and spinal cord of healthy individuals are relatively low. However, recent studies demonstrated a CB2 upregulation on activated microglia upon neuroinflammation, an indicator of neurodegeneration. Our research group aims to develop a suitable positron emission tomography (PET) tracer to visualize the CB2 receptor in patients suffering from neurodegenerative diseases. Herein we report two novel thiophene-based 11C-labeled PET ligands designated [11C]AAT-015 and [11C]AAT-778. The reference compounds were synthesized using Gewald reaction conditions to obtain the aminothiophene intermediates, followed by amide formation. Saponification of the esters provided their corresponding precursors. Binding affinity studies revealed Ki-values of 3.3 ± 0.5 nM (CB2) and 1.0 ± 0.2 μM (CB1) for AAT-015. AAT-778 showed similar Ki-values of 4.3 ± 0.7 nM (CB2) and 1.1 ± 0.1 μM (CB1). Radiosynthesis was carried out under basic conditions using [11C]iodomethane as methylating agent. After semi-preparative HPLC purification both radiolabeled compounds were obtained in 99% radiochemical purity and the radiochemical yields ranged from 12 to 37%. Specific activity was between 96 and 449 GBq/μmol for both tracers. In order to demonstrate CB2 specificity of [11C]AAT-015 and [11C]AAT-778, we carried out autoradiography studies using CB2-positive mouse/rat spleen tissues. The obtained results revealed unspecific binding in spleen tissue that was not blocked by an excess of CB2-specific ligand GW402833. For in vivo analysis, [11C]AAT-015 was administered to healthy rats via tail-vein injection

  13. Autophagy activation by novel inducers prevents BECN2-mediated drug tolerance to cannabinoids.

    Science.gov (United States)

    Kuramoto, Kenta; Wang, Nan; Fan, Yuying; Zhang, Weiran; Schoenen, Frank J; Frankowski, Kevin J; Marugan, Juan; Zhou, Yifa; Huang, Sui; He, Congcong

    2016-09-01

    Cannabinoids and related drugs generate profound behavioral effects (such as analgesic effects) through activating CNR1 (cannabinoid receptor 1 [brain]). However, repeated cannabinoid administration triggers lysosomal degradation of the receptor and rapid development of drug tolerance, limiting the medical use of marijuana in chronic diseases. The pathogenic mechanisms of cannabinoid tolerance are not fully understood, and little is known about its prevention. Here we show that a protein involved in macroautophagy/autophagy (a conserved lysosomal degradation pathway), BECN2 (beclin 2), mediates cannabinoid tolerance by preventing CNR1 recycling and resensitization after prolonged agonist exposure, and deletion of Becn2 rescues CNR1 activity in mouse brain and conveys resistance to analgesic tolerance to chronic cannabinoids. To target BECN2 therapeutically, we established a competitive recruitment model of BECN2 and identified novel synthetic, natural or physiological stimuli of autophagy that sequester BECN2 from its binding with GPRASP1, a receptor protein for CNR1 degradation. Co-administration of these autophagy inducers effectively restores the level and signaling of brain CNR1 and protects mice from developing tolerance to repeated cannabinoid usage. Overall, our findings demonstrate the functional link among autophagy, receptor signaling and animal behavior regulated by psychoactive drugs, and develop a new strategy to prevent tolerance and improve medical efficacy of cannabinoids by modulating the BECN2 interactome and autophagy activity. PMID:27305347

  14. Toll-Like Receptor 9 Agonists for Cancer Therapy

    Directory of Open Access Journals (Sweden)

    Davide Melisi

    2014-08-01

    Full Text Available The immune system has acquired increasing importance as a key player in cancer maintenance and growth. Thus, modulating anti-tumor immune mediators has become an attractive strategy for cancer treatment. Toll-like receptors (TLRs have gradually emerged as potential targets of newer immunotherapies. TLR-9 is preferentially expressed on endosome membranes of B-cells and plasmacytoid dendritic cells (pDC and is known for its ability to stimulate specific immune reactions through the activation of inflammation-like innate responses. Several synthetic CpG oligonucleotides (ODNs have been developed as TLR-9 agonists with the aim of enhancing cancer immune surveillance. In many preclinical models, CpG ODNs were found to suppress tumor growth and proliferation both in monotherapy and in addition to chemotherapies or target therapies. TLR-9 agonists have been also tested in several clinical trials in patients with solid tumors. These agents showed good tolerability and usually met activity endpoints in early phase trials. However, they have not yet been demonstrated to significantly impact survival, neither as single agent treatments, nor in combination with chemotherapies or cancer vaccines. Further investigations in larger prospective studies are required.

  15. Nicotinic acetylcholine receptor agonist attenuates ILC2-dependent airway hyperreactivity

    Science.gov (United States)

    Galle-Treger, Lauriane; Suzuki, Yuzo; Patel, Nisheel; Sankaranarayanan, Ishwarya; Aron, Jennifer L.; Maazi, Hadi; Chen, Lin; Akbari, Omid

    2016-01-01

    Allergic asthma is a complex and chronic inflammatory disorder that is associated with airway hyperreactivity (AHR) and driven by Th2 cytokine secretion. Type 2 innate lymphoid cells (ILC2s) produce large amounts of Th2 cytokines and contribute to the development of AHR. Here, we show that ILC2s express the α7-nicotinic acetylcholine receptor (α7nAChR), which is thought to have an anti-inflammatory role in several inflammatory diseases. We show that engagement of a specific agonist with α7nAChR on ILC2s reduces ILC2 effector function and represses ILC2-dependent AHR, while decreasing expression of ILC2 key transcription factor GATA-3 and critical inflammatory modulator NF-κB, and reducing phosphorylation of upstream kinase IKKα/β. Additionally, the specific α7nAChR agonist reduces cytokine production and AHR in a humanized ILC2 mouse model. Collectively, our data suggest that α7nAChR expressed by ILC2s is a potential therapeutic target for the treatment of ILC2-mediated asthma. PMID:27752043

  16. Benzyl-1,2,4-triazoles as CB1 Cannabinoid Receptor Ligands: Preparation and In Vitro Pharmacological Evaluation

    Science.gov (United States)

    Hernandez-Folgado, Laura; Decara, Juan; Rodríguez de Fonseca, Fernando; Goya, Pilar; Jagerovic, Nadine

    2016-01-01

    In a previous study, we have identified 3-alkyl-1,5-diaryl-1H-1,2,4-triazoles to be a novel class of cannabinoid type 1 receptor (CB1R) antagonists. In order to expand the number of cannabinoid ligands with a central 1,2,4-triazole scaffold, we have synthesized a novel series of 1-benzyl-1H-1,2,4-triazoles, and some of them were evaluated by CB1R radioligand binding assays. Compound 12a showed the most interesting pharmacological properties, possessing a CB1R affinity in the nanomolar range. PMID:27127651

  17. Use of thrombopoietin receptor agonists in childhood immune thrombocytopenia

    Directory of Open Access Journals (Sweden)

    Angelica Maria Garzon

    2015-08-01

    Full Text Available Most children with immune thrombocytopenia (ITP will have spontaneous remission regardless of therapy, while about 20% will go on to have chronic ITP. In those children with chronic ITP who need treatment, standard therapies for acute ITP may have adverse effects that complicate their long term use. Thus, alternative treatment options are needed for children with chronic ITP. Thrombopoietin receptor agonists (TPO-RA have been shown to be safe and efficacious in adults with ITP, and represent a new treatment option for children with chronic ITP. One TPO-RA, eltrombopag, is now approved for children. Clinical trials in children are ongoing and data is emerging on safety and efficacy. This review will focus on the physiology of TPO-RA, their clinical use in children, as well as the long term safety issues that need to be considered when using these agents

  18. Recent advances in the development of farnesoid X receptor agonists.

    Science.gov (United States)

    Ali, Ahmad H; Carey, Elizabeth J; Lindor, Keith D

    2015-01-01

    Farnesoid X receptors (FXRs) are nuclear hormone receptors expressed in high amounts in body tissues that participate in bilirubin metabolism including the liver, intestines, and kidneys. Bile acids (BAs) are the natural ligands of the FXRs. FXRs regulate the expression of the gene encoding for cholesterol 7 alpha-hydroxylase, which is the rate-limiting enzyme in BA synthesis. In addition, FXRs play a critical role in carbohydrate and lipid metabolism and regulation of insulin sensitivity. FXRs also modulate live growth and regeneration during liver injury. Preclinical studies have shown that FXR activation protects against cholestasis-induced liver injury. Moreover, FXR activation protects against fatty liver injury in animal models of nonalcoholic fatty liver disease (NAFLD) and nonalcoholic steatohepatitis (NASH), and improved hyperlipidemia, glucose intolerance, and insulin sensitivity. Obeticholic acid (OCA), a 6α-ethyl derivative of the natural human BA chenodeoxycholic acid (CDCA) is the first-in-class selective FXR agonist that is ~100-fold more potent than CDCA. Preliminary human clinical trials have shown that OCA is safe and effective. In a phase II clinical trial, administration of OCA was well-tolerated, increased insulin sensitivity and reduced markers of liver inflammation and fibrosis in patients with type II diabetes mellitus and NAFLD. In two clinical trials of OCA in patients with primary biliary cirrhosis (PBC), a progressive cholestatic liver disease, OCA significantly reduced serum alkaline phosphatase (ALP) levels, an important disease marker that correlates well with clinical outcomes of patients with PBC. Together, these studies suggest that FXR agonists could potentially be used as therapeutic tools in patients suffering from nonalcoholic fatty and cholestatic liver diseases. Larger and Longer-term studies are currently ongoing. PMID:25705637

  19. The dopamine D1 receptor agonist SKF-82958 effectively increases eye blinking count in common marmosets.

    Science.gov (United States)

    Kotani, Manato; Kiyoshi, Akihiko; Murai, Takeshi; Nakako, Tomokazu; Matsumoto, Kenji; Matsumoto, Atsushi; Ikejiri, Masaru; Ogi, Yuji; Ikeda, Kazuhito

    2016-03-01

    Eye blinking is a spontaneous behavior observed in all mammals, and has been used as a well-established clinical indicator for dopamine production in neuropsychiatric disorders, including Parkinson's disease and Tourette syndrome [1,2]. Pharmacological studies in humans and non-human primates have shown that dopamine agonists/antagonists increase/decrease eye blinking rate. Common marmosets (Callithrix jacchus) have recently attracted a great deal of attention as suitable experimental animals in the psychoneurological field due to their more developed prefrontal cortex than rodents, easy handling compare to other non-human primates, and requirement for small amounts of test drugs. In this study, we evaluated the effects of dopamine D1-4 receptors agonists on eye blinking in common marmosets. Our results show that the dopamine D1 receptor agonist SKF-82958 and the non-selective dopamine receptor agonist apomorphine significantly increased common marmosets eye blinking count, whereas the dopamine D2 agonist (+)-PHNO and the dopamine D3 receptor agonist (+)-PD-128907 produced somnolence in common marmosets resulting in a decrease in eye blinking count. The dopamine D4 receptor agonists PD-168077 and A-41297 had no effect on common marmosets' eye blinking count. Finally, the dopamine D1 receptor antagonist SCH 39166 completely blocked apomorphine-induced increase in eye blinking count. These results indicate that eye blinking in common marmosets may be a useful tool for in vivo screening of novel dopamine D1 receptor agonists as antipsychotics. PMID:26675887

  20. Resistance to diet-induced adiposity in cannabinoid receptor-1 deficient mice is not due to impaired adipocyte function

    OpenAIRE

    Oosterveer, Maaike H.; Koolman, Anniek H; de Boer, Pieter T; Bos, Trijnie; Bleeker, Aycha; Bloks, Vincent W.; Kuipers, Folkert; Sauer, Pieter J. J.; van Dijk, Gertjan

    2011-01-01

    Background: Overactivity and/or dysregulation of the endocannabinoid system (ECS) contribute to development of obesity. In vitro studies indicate a regulatory role for the cannabinoid receptor 1 (CB1) in adipocyte function and CB1-receptor deficient (CB1-/-) mice are resistant to high fat diet-induced obesity. Whether this phenotype of CB1-/- mice is related to altered fat metabolism in adipose tissue is unknown. Methods: We evaluated adipose tissue differentiation/proliferation markers and q...

  1. Basolateral amygdala CB1 cannabinoid receptors are involved in cross state-dependent memory retrieval between morphine and ethanol.

    Science.gov (United States)

    Ofogh, Sattar Norouzi; Rezayof, Ameneh; Sardari, Maryam; Ghasemzadeh, Zahra

    2016-09-01

    Ethanol and morphine are largely co-abused and affect memory formation. The present study intended to investigate the involvement of cannabinoid CB1 receptors of the basolateral amygdala (BLA) in cross state-dependent memory retrieval between morphine and ethanol. Adult male Wistar rats received bilateral cannulation of the BLA, and memory retrieval was measured in step-through type passive avoidance apparatus. Our results showed that post-training intraperitoneal (i.p.) administration of morphine (6mg/kg) induced amnesia. Pre-test administration of ethanol (0.5g/kg, i.p.) significantly improved morphine-induced memory impairment, suggesting that there is cross state-dependent memory retrieval between morphine and ethanol. It should be considered that pre-test administration of ethanol (0.1 and 0.5g/kg, i.p.) by itself had no effect on memory retrieval in the passive avoidance task. Interestingly, pre-test intra-BLA microinjection of different doses of WIN55,212-2 (0.1, 0.2 and 0.3μg/rat), a non-selective CB1/CB2 receptor agonist, plus an ineffective dose of ethanol (0.1g/kg, i.p.) improved morphine-induced memory impairment. Intra-BLA microinjection of AM251 (0.4-0.6ng/rat), a selective CB1 receptor antagonist, inhibited the improved effect of ethanol (0.5g/kg, i.p.) on morphine response. Pre-test intra-BLA microinjection of WIN55,212-2 or AM251 had no effect on memory retrieval or morphine-induced amnesia. Taken together, it can be concluded that morphine and ethanol can induce state-dependent memory retrieval. In addition, the BLA endocannabinoid system mediates via CB1 receptors the functional interaction of morphine and ethanol state-dependent memory retrieval which may depend on the rewarding effects of the drugs. PMID:27327764

  2. Discovery of benzamide analogues as a novel class of 5-HT3 receptor agonists

    DEFF Research Database (Denmark)

    Jørgensen, Charlotte Grube; Frølund, Bente Flensborg; Kehler, Jan;

    2011-01-01

    A 5-HT(3) receptor agonist based on a benzamide scaffold was identified in a screening of a small commercial compound library, and an elaborate SAR study originating from this hit was performed. The design, synthesis, and functional characterisation of benzamide analogues at the 5-HT(3) A receptor...... yielded substantial information concerning the analogues as 5-HT(3) receptor agonists. However, the potencies of the derived analogues were not significantly improved over that of the initial hit. The benzamide scaffold constitutes a novel type of 5-HT(3) receptor agonist, as it does not possess...

  3. Activation of Cannabinoid Receptor 2 Ameliorates DSS-Induced Colitis through Inhibiting NLRP3 Inflammasome in Macrophages.

    Science.gov (United States)

    Ke, Ping; Shao, Bo-Zong; Xu, Zhe-Qi; Wei, Wei; Han, Bin-Ze; Chen, Xiong-Wen; Su, Ding-Feng; Liu, Chong

    2016-01-01

    Activation of cannabinoid receptor 2 (CB2R) ameliorates inflammation, but the underlying mechanism remains unclear. In the present study, we examined whether activation of CB2R could suppress the nucleotide-binding domain and leucine-rich repeat protein 3 (NLRP3) inflammasome. In peritoneal macrophages isolated from C57BL/6 mice, LPS/DSS challenge for 24 h increased the expression of the components of NLRP3 inflammasome NLRP3, Casp-1 p20/Casp-1 p45 ratio, proIL-1β and IL-1β and also enhanced autophagy (LC3-II/LC3-I ratio, Beclin-1 and SQSTM1). Pretreatment of peritoneal macrophages with HU 308, a selective CB2R agonist, attenuated LPS/DSS-induced NLRP3 inflammasome activation, but further enhanced autophagy. In comparison with wild-type (WT) control, peritoneal macrophages from CB2R knockout (KO) mice had more robust NLRP3 inflammasome activation and attenuated autophagy upon LPS/DSS challenge. Knockdown autophagy-related gene 5 (Atg5) with a siRNA in peritoneal macrophages attenuated the inhibitory effects of HU 308 on LPS/DSS-induced NLRP3 inflammasome activation in vitro. In vivo, HU308 treatment attenuated DSS-induced colitis mice associated with reduced colon inflammation and inhibited NLRP3 inflammasome activation in wild-type mice. In CB2R KO mice, DSS-induced inflammation and NLRP3 inflammasome activation were more pronounced than those in WT control. Finally, we demonstrated that AMPK-mTOR-P70S6K signaling pathway was involved in this CB2R-mediated process. We conclude that activation of CB2R ameliorates DSS-induced colitis through enhancing autophagy that may inhibit NLRP3 inflammasome activation in macrophages.

  4. Modulatory effects by CB1 receptors on rat spinal locomotor networks after sustained application of agonists or antagonists.

    Science.gov (United States)

    Veeraraghavan, P; Nistri, A

    2015-09-10

    Sustained administration of cannabinoid agonists acting on neuronal CB1 receptors (CB1Rs) are proposed for treating spasticity and chronic pain. The impact of CB1Rs on mammalian locomotor networks remains, however, incompletely understood. To clarify how CB1Rs may control synaptic activity and locomotor network function, we used the rat spinal cord in vitro which is an advantageous model to investigate locomotor circuit mechanisms produced by the local central pattern generator. Neither the CB1 agonist anandamide (AEA) nor the CB1R antagonist AM-251 evoked early (3-24h largely impaired locomotor network activity induced by DR stimuli or neurochemicals, and depressed disinhibited bursting without changing reflex amplitude or inducing neurotoxicity even if CB1R immunoreactivity was lowered in the central region. Since CB1R activation usually inhibits cyclic adenosine monophosphate (cAMP) synthesis, we investigated how a 24-h application of AEA or AM-251 affected basal or forskolin-stimulated cAMP levels. While AEA decreased them in an AM-251-sensitive manner, AM-251 per se did not change resting or stimulated cAMP. Our data suggest that CB1Rs may control the circuit gateway regulating the inflow of sensory afferent inputs into the locomotor circuits, indicating a potential site of action for restricting peripheral signals disruptive for locomotor activity.

  5. Anandamide, a natural ligand for the peripheral cannabinoid receptor is a novel synergistic growth factor for hematopoietic cells.

    Science.gov (United States)

    Valk, P; Verbakel, S; Vankan, Y; Hol, S; Mancham, S; Ploemacher, R; Mayen, A; Löwenberg, B; Delwel, R

    1997-08-15

    We recently demonstrated that the gene encoding the peripheral cannabinoid receptor (Cb2) may be a proto-oncogene involved in murine myeloid leukemias. We show here that Cb2 may have a role in hematopoietic development. RNAse protection analysis showed that Cb2 is normally expressed in spleen and thymus. Cb2 mRNA is also expressed in 45 of 51 cell lines of distinct hematopoietic lineages, ie, myeloid, macrophage, mast, B-lymphoid, T-lymphoid, and erythroid cells. The effect of the fatty acid anandamide, an endogenous ligand for cannabinoid receptors, on primary murine marrow cells and hematopoietic growth factor (HGF)-dependent cell lines was then investigated. In vitro colony cultures of normal mouse bone marrow cells showed anandamide to potentiate interleukin-3 (IL-3)-induced colony growth markedly. Whereas HGFs alone stimulate proliferation of the various cell lines in serum-free culture only weakly, anandamide enhances the proliferative response of the cell lines to HGFs profoundly. This was apparent for responses induced by IL-3, granulocyte-macrophage colony-stimulating factor, granulocyte colony-stimulating factor, and erythropoietin. Anandamide was already effective at concentrations as low as 0.1 to 0.3 micromol/L and plateau effects were reached at 0.3 to 3 micromol/L. The addition of anandamide as single growth factor had no effect. The costimulatory effect of anandamide was not evident when cells were cultured with fetal calf serum (FCS), suggesting that FCS contains anandamide or another ligand capable of activating the peripheral cannabinoid receptor. Other cannabinoid ligands did not enhance the proliferative responsiveness of hematopoietic cells to HGFs. Transfection experiments of Cb2 in myeloid 32D cells showed that anandamide specifically activates proliferation through activation of the peripheral cannabinoid receptor. Anandamide appears to be a novel and synergistic growth stimulator for hematopoietic cells. PMID:9269762

  6. The Combined Inhibitory Effect of the Adenosine A1 and Cannabinoid CB1 Receptors on cAMP Accumulation in the Hippocampus Is Additive and Independent of A1 Receptor Desensitization

    Directory of Open Access Journals (Sweden)

    André Serpa

    2015-01-01

    Full Text Available Adenosine A1 and cannabinoid CB1 receptors are highly expressed in hippocampus where they trigger similar transduction pathways. We investigated how the combined acute activation of A1 and CB1 receptors modulates cAMP accumulation in rat hippocampal slices. The CB1 agonist WIN55212-2 (0.3–30 μM decreased forskolin-stimulated cAMP accumulation with an EC50 of 6.6 ± 2.7 μM and an Emax⁡ of 31% ± 2%, whereas for the A1 agonist, N6-cyclopentyladenosine (CPA, 10–150 nM, an EC50 of 35 ± 19 nM, and an Emax⁡ of 29% ± 5 were obtained. The combined inhibitory effect of WIN55212-2 (30 μM and CPA (100 nM on cAMP accumulation was 41% ± 6% (n=4, which did not differ (P>0.7 from the sum of the individual effects of each agonist (43% ± 8% but was different (P<0.05 from the effects of CPA or WIN55212-2 alone. Preincubation with CPA (100 nM for 95 min caused desensitization of adenosine A1 activity, which did not modify the effect of WIN55212-2 (30 μM on cAMP accumulation. In conclusion, the combined effect of CB1 and A1 receptors on cAMP formation is additive and CB1 receptor activity is not affected by short-term A1 receptor desensitization.

  7. Cannabinoids as pharmacotherapies for neuropathic pain: from the bench to the bedside.

    Science.gov (United States)

    Rahn, Elizabeth J; Hohmann, Andrea G

    2009-10-01

    Neuropathic pain is a debilitating form of chronic pain resulting from nerve injury, disease states, or toxic insults. Neuropathic pain is often refractory to conventional pharmacotherapies, necessitating validation of novel analgesics. Cannabinoids, drugs that share the same target as Delta(9)-tetrahydrocannabinol (Delta(9)-THC), the psychoactive ingredient in cannabis, have the potential to address this unmet need. Here, we review studies evaluating cannabinoids for neuropathic pain management in the clinical and preclinical literature. Neuropathic pain associated with nerve injury, diabetes, chemotherapeutic treatment, human immunodeficiency virus, multiple sclerosis, and herpes zoster infection is considered. In animals, cannabinoids attenuate neuropathic nociception produced by traumatic nerve injury, disease, and toxic insults. Effects of mixed cannabinoid CB(1)/CB(2) agonists, CB(2) selective agonists, and modulators of the endocannabinoid system (i.e., inhibitors of transport or degradation) are compared. Effects of genetic disruption of cannabinoid receptors or enzymes controlling endocannabinoid degradation on neuropathic nociception are described. Specific forms of allodynia and hyperalgesia modulated by cannabinoids are also considered. In humans, effects of smoked marijuana, synthetic Delta(9)-THC analogs (e.g., Marinol, Cesamet) and medicinal cannabis preparations containing both Delta(9)-THC and cannabidiol (e.g., Sativex, Cannador) in neuropathic pain states are reviewed. Clinical studies largely affirm that neuropathic pain patients derive benefits from cannabinoid treatment. Subjective (i.e., rating scales) and objective (i.e., stimulus-evoked) measures of pain and quality of life are considered. Finally, limitations of cannabinoid pharmacotherapies are discussed together with directions for future research. PMID:19789075

  8. Dihydromorphine-peptide hybrids with delta receptor agonistic and mu receptor antagonistic actions

    Energy Technology Data Exchange (ETDEWEB)

    Smith, C.B.; Medzihradsky, F.; Woods, J.H.

    1986-03-05

    The actions of two morphine derivatives with short peptide side chains were evaluated upon the contraction of the isolated mouse vas deferens and upon displacement of /sup 3/H-etorphine from rat brain membranes. NIH-9833 (N-(6,14-endoetheno-7,8-dihydromorphine-7-alpha-carbonyl)-L-phenylalanyl-L-leucine ethyl ester HCl) was a potent agonist upon the vas deferens. Its EC50 for inhibition of the twitch was 1.2 +/- 0.1 nM. Both naltrexone (10/sup -7/ M) a relatively nonselective opioid antagonist, and ICI-174864 (10/sup -/' M) a highly selective delta receptor antagonist, blocked the actions of NIH-9833 which indicates that this drug is a delta receptor agonist. In contrast, NIH-9835 (N-(6,14-endoetheno-7,8-dihydromorphine-7-alpha-carbonyl)-L-glycyl-L-phenylalanyl-L-leucine ethyl ester HCl), which differs from NIH-9835 by the presence of a single amino acid residue, was devoid of opioid agonistic activity but was a potent antagonist of the inhibitory actions on the vas deferens of morphine and sufentanil. NIH-9833 and NIH-9835 were potent displacers of /sup 3/H-etorphine from rat cerebral membranes with EC50's of 0.58 nM and 1.7 nM, respectively. The observation that addition of a single glycyl group changes a dihydromorphine-peptide analog from a potent delta receptor agonist to an equally potent mu receptor antagonist suggests that the two receptor sites might be structurally quite similar.

  9. The cannabinoid type-1 receptor carboxyl-terminus, more than just a tail.

    Science.gov (United States)

    Stadel, Rebecca; Ahn, Kwang H; Kendall, Debra A

    2011-04-01

    The cannabinoid type-1 (CB(1)) receptor is a G protein-coupled receptor that binds the main active ingredient of marijuana, Δ(9)-tetrahydrocannabinol, and has been implicated in several disease states, including drug addiction, anxiety, depression, obesity, and chronic pain. In the two decades since the discovery of CB(1), studies at the molecular level have centered on the transmembrane core. This interest has now expanded as we discover that other regions of CB(1), including the CB(1) carboxyl-terminus, have critical structures that are important for CB(1) activity and regulation. Following the recent description of the three dimensional structure of the full-length CB(1) carboxyl-terminal tail [Biopolymers (2009) vol. 91, pp. 565-573], several residues and structural motifs including two α-helices (termed H8 and H9) have been postulated to interact with common G protein-coupled receptor accessory proteins, such as G-proteins and β-arrestins. This discourse will focus on the CB(1) carboxyl-terminus; our current understanding of the structural features of this region, evidence for its interaction with proteins, and the impact of structure on the binding and regulatory function of CB(1) accessory proteins. The involvement of the carboxyl-terminus in the receptor life cycle including activation, desensitization, and internalization will be highlighted.

  10. Regulative effect of anandamide-mediated cannabinoid receptor in rats with visceral hypersensitivity

    Directory of Open Access Journals (Sweden)

    Yu-qin HE

    2012-11-01

    Full Text Available Objective  To investigate the role of anandamide(ANA-mediated cannabinoid receptor 1(CB1 on the acquisition of visceral hypersensitivity in rats, and explore its underlying mechanism. Methods  The visceral hypersensitivity non-noxious/noxious colorectal distension (NNCRD/NCRD model of rat was reproduced by ovalbumin (OVA sensitization combined with NNCRD/NCRD. Fifty-four rats were randomly divided into control group (n=7, saline+CRD group (n=7, OVA+CRD+dimethyl sulfoxide (DMSO group (n=8, OVA+CRD+different concentrations of ANA (0.5, 5.0, 10.0mg/kg groups (8 each, and OVA+CRD+ANA+AM251 group (n=8. The expression and quantitative assessment of CB1 were monitored by immunoflurorescence and laser scanning confocal analysis. The visceral sensitivity was evaluated by the area under curve (AUC of myoelectrical activity of abdominal wall muscle. Results  By NCRD at 80mmHg, the density of CB1 immunofluorescence intensity was significantly higher in L4–L6 of the spinal cord of the rats in saline+CRD group compared with that in control group (P 0.05. By NCRD at 80mmHg, the VMR-AUC increased obviously in OVA+CRD+DMSO group as compared with that of saline+CRD group, but it decreased significantly in OVA+CRD+high concentration ANA group (P < 0.05. When AM251 was intravenously given, VMR-AUC increased significantly in OVA+CRD+ANA+AM251 group compared with that in OVA+CRD+different concentrations of ANA groups (P < 0.05. Conclusions Intravenous administration of ANA may mitigate the visceral nociception induced by basic OVAsensitization combined with NCRD stimulation in CB1-mediated manner. It indicated that anandamide-mediated CB1 cannabinoid receptor may regulate the development and maintenance of visceral hypersensitivity.

  11. Diacylglycerol lipase a knockout mice demonstrate metabolic and behavioral phenotypes similar to those of cannabinoid receptor 1 knockout mice

    Directory of Open Access Journals (Sweden)

    David R Powell

    2015-06-01

    Full Text Available After creating >4650 knockouts (KOs of independent mouse genes, we screened them by high-throughput phenotyping and found that cannabinoid receptor 1 (Cnr1 KO mice had the same lean phenotype published by others. We asked if our KOs of DAG lipase a or b (Dagla or Daglb, which catalyze biosynthesis of the endocannabinoid (EC 2-Arachidonoylglycerol (2-AG, or Napepld, which catalyzes biosynthesis of the EC anandamide, shared the lean phenotype of Cnr1 KO mice. We found that Dagla KO mice, but not Daglb or Napepld KO mice, were among the leanest of 3651 chow-fed KO lines screened. In confirmatory studies, chow- or high fat diet-fed Dagla and Cnr1 KO mice were leaner than wild type (WT littermates; when data from multiple cohorts of adult mice were combined, body fat was 47% and 45% lower in Dagla and Cnr1 KO mice, respectively, relative to WT values. In contrast, neither Daglb nor Napepld KO mice were lean. Weanling Dagla KO mice ate less than WT mice and had body weight similar to pair-fed WT mice, and adult Dagla KO mice had normal activity and VO2 levels, similar to Cnr1 KO mice. Our Dagla and Cnr1 KO mice also had low fasting insulin, triglyceride and total cholesterol levels, and after a glucose challenge had normal glucose but very low insulin levels. Dagla and Cnr1 KO mice also showed similar responses to a battery of behavioral tests. These data suggest: 1 the lean phenotype of young Dagla and Cnr1 KO mice is mainly due to hypophagia; 2 in pathways where ECs signal through Cnr1 to regulate food intake and other metabolic and behavioral phenotypes observed in Cnr1 KO mice, Dagla alone provides the 2-AG that serves as the EC signal; and 3 small molecule Dagla inhibitors with a pharmacokinetic profile similar to that of Cnr1 inverse agonists are likely to mirror the ability of these Cnr1 inverse agonists to lower body weight and improve glycemic control in obese patients with type 2 diabetes, but may also induce undesirable neuropsychiatric

  12. Cannabinoid CB1 receptor calibrates excitatory synaptic balance in the mouse hippocampus.

    Science.gov (United States)

    Monory, Krisztina; Polack, Martin; Remus, Anita; Lutz, Beat; Korte, Martin

    2015-03-01

    The endocannabinoid system negatively regulates the release of various neurotransmitters in an activity-dependent manner, thereby influencing the excitability of neuronal circuits. In the hippocampus, cannabinoid type 1 (CB1) receptor is present on both GABAergic and glutamatergic axon terminals. CB1 receptor-deficient mice were previously shown to have increased hippocampal long-term potentiation (LTP). In this study, we have investigated the consequences of cell-type-specific deletion of the CB1 receptor on the induction of hippocampal LTP and on CA1 pyramidal cell morphology. Deletion of CB1 receptor in GABAergic neurons in GABA-CB1-KO mice leads to a significantly decreased hippocampal LTP compared with WT controls. Concomitantly, CA1 pyramidal neurons have a significantly reduced dendritic branching both on the apical and on the basal dendrites. Moreover, the average spine density on the apical dendrites of CA1 pyramidal neurons is significantly diminished. In contrast, in mice lacking CB1 receptor in glutamatergic cells (Glu-CB1-KO), hippocampal LTP is significantly enhanced and CA1 pyramidal neurons show an increased branching and an increased spine density in the apical dendritic region. Together, these results indicate that the CB1 receptor signaling system both on inhibitory and excitatory neurons controls functional and structural synaptic plasticity of pyramidal neurons in the hippocampal CA1 region to maintain an appropriate homeostatic state upon neuronal activation. Consequently, if the CB1 receptor is lost in either neuronal population, an allostatic shift will occur leading to a long-term dysregulation of neuronal functions.

  13. CB1 Cannabinoid Receptor-Dependent and -Independent Inhibition of Depolarization-Induced Calcium Influx in Oiigodendrocytes

    Institute of Scientific and Technical Information of China (English)

    SUSANA MATO; ELENA ALBERDI; CATHERINE LEDENT; MASAHIKO WATANABE; AND CARLOS MATUTE

    2009-01-01

    Regulation of Ca2+ homeostasis plays a critical role in oligodendrocyte function and survival. Canna-binoid CB2 and CB2 receptors have been shown to regulate Ca2+ levels and/or K+ currents in a variety of cell types. In this study we investigated the effect of cannabinoid compounds on the Ca2+ influx elicited in cultured oligodendro-cytes by transient membrane depolarization with an elevated extracellular K+ concentration (50 mM). The CB2 re-ceptor agonist arachidonoyl-chloro-ethanolamide (ACEA) elicited a concentration-dependent inhibition of depolariza-tion-evoked Ca2+ transients in oligodendroglial somata with a maximal effect (94 ± 3)% and an EC50 of 1.3 ±0.03 μM. This activity was mimicked by the CB2/CB2 agonist CP55,940, as well as by the endocannabinoids N-arachidonoyl-ethanolamine (anandamide, AEA) and 2-arachidonoylglycerol (2-AG), whereas the CB2 receptor se-lective agonist JWH133 was ineffective. The CB2 receptor antagonist AM251 (1 μM) also reduced the Ca2+ response evoked by high extracellular K+ and did not prevent the inhibition elicited by ACEA (3 μM). Nevertheless, the a-bility of ACEA and AEA to reduce depolarization-evoked Ca2+ transients was significantly reduced in oligodendro-cytes from CB2 receptor knockout mice, as well as by pretreatment with pertussis toxin. Bath application of the in-wardly rectifying K+ channels (Kir channels) blockers BaCl2 (300 μM) and CsCl2 (1 mM) reduced the size of volt-age-induced Ca2+ influx and partially prevented the inhibitory effect of ACEA. Our results indicate that eannabinoids inhibit depolarization-evoked Ca2+ transients in oligodendrocytes via CB2 receptor-independent and -dependent mech-anisms that involve the activation of PTX-sensitive Gi/o proteins and the blockade of Kir channels. C 2008 Wiley-Liss, Inc.%Ca2+稳态平衡的调节在少突胶质细胞功能和存活中起重要作用.大麻素CB1和CB2受体在许多细胞中调节Ca2+水平和/或K+电流.本文利用培养的少突胶质细

  14. Development of novel silicon-containing inverse agonists of retinoic acid receptor-related orphan receptors.

    Science.gov (United States)

    Toyama, Hirozumi; Nakamura, Masaharu; Nakamura, Masahiko; Matsumoto, Yotaro; Nakagomi, Madoka; Hashimoto, Yuichi

    2014-03-15

    Retinoic acid receptor (RAR)-related orphan receptors (RORs) regulate a variety of physiological processes, including hepatic gluconeogenesis, lipid metabolism, circadian rhythm and immune function. The RAR agonist: all-trans retinoic acid was reported to be an RORβ inverse agonist, but no information is available regarding ROR activity of its synthetic analogue Am580. Therefore, we screened Am580 and some related tetramethyltetrahydronaphthalene derivatives and carried out structural development studies, including substitution of carbon atoms with silicon, with the aim of creating a potent ROR transcriptional inhibitor. The phenyl amide disila compound 22 showed the most potent ROR-inhibitory activity among the compounds examined. Its activity towards RORα, RORβ and RORγ was increased compared to that of Am580. The IC₅₀ values for RORα, RORβ and RORγ are 1.3, >10 and 4.5 μM, respectively.

  15. Involvement of a non-CB1/CB2 cannabinoid receptor in the aqueous humor outflow-enhancing effects of abnormal-cannabidiol

    Science.gov (United States)

    Qiao, Zhuanhong; Kumar, Akhilesh; Kumar, Pritesh; Song, Zhao-Hui

    2016-01-01

    The purpose of this study was to investigate the effects of abnormal-cannabidiol (abn-cbd), a non-psychoactive cannabinoid agonist, on aqueous humor outflow via the trabecular meshwork (TM) of porcine eye, and to examine the involvement of a non-CB1/CB2 cannabinoid receptor and the p42/44 mitogen-activated protein kinase (p42/44 MAPK) pathway. The effects of abn-cbd on aqueous humor outflow were measured using a porcine anterior segment perfused organ culture model. The activation of p42/44 MAPK by abn-cbd was determined in cultured TM cells with western blot analysis using an anti-phospho-p42/44 MAPK antibody. Administration of abn-cbd caused a concentration-dependent enhancement of aqueous humor outflow facility with a maximum effect (155.0 ± 11.7% of basal outflow facility) after administration of 30 nM abn-cbd. Pretreatment with 1 μM of O-1918, a cannabidiol analog that acts as a selective antagonist at the non-CB1/CB2 receptor, produced a full antagonism of 30 nM abn-cbd induced increase of aqueous humor outflow facility. Pretreatment with 1 μM of CB1 antagonist SR141716A partially blocked, whereas pretreatment with either 1 μM of CB1 antagonist AM251 or 1 μM of CB2 antagonist SR144528 had no effect on abn-cbd induced enhancement of outflow facility. Treatment of TM cells with 30 nM of abn-cbd activated p42/44 MAPK, which was blocked completely by pretreatment with O-1918, and partially by pretreatment with SR141716A, but not by either AM251 or SR144528. In addition, PD98059, an inhibitor of p42/44 MAPK pathway, blocked completely the abn-cbd induced p42/44 MAPK activation and blocked partially the abn-cbd induced enhancement of outflow facility. In conclusion, the results from this study demonstrate that abn-cbd increases aqueous humor outflow through the TM pathway of the eye, and this effect is mediated by a non-CB1/CB2 cannabinoid receptor, with an involvement of p42/44 MAPK signaling pathway. PMID:22580290

  16. Cannabinoid CB1 receptors in the dorsal hippocampus and prelimbic medial prefrontal cortex modulate anxiety-like behavior in rats: additional evidence.

    Science.gov (United States)

    Lisboa, Sabrina F; Borges, Anna A; Nejo, Priscila; Fassini, Aline; Guimarães, Francisco S; Resstel, Leonardo B

    2015-06-01

    Endocannabinoids (ECBs) such as anandamide (AEA) act by activating cannabinoid type 1 (CB1) or 2 (CB2) receptors. The anxiolytic effect of drugs that facilitate ECB effects is associated with increase in AEA levels in several encephalic areas, including the prefrontal cortex (PFC). Activation of CB1 receptors by CB1 agonists injected directly into these areas is usually anxiolytic. However, depending on the encephalic region being investigated and on the stressful experiences, opposite effects were observed, as reported in the ventral HIP. In addition, contradictory results have been reported after CB1 activation in the dorsal HIP (dHIP). Therefore, in the present paper we have attempted to verify if directly interfering with ECB metabolism/reuptake in the prelimbic (PL) portion of the medial PFC (MPFC) and dHIP would produce different effects in two conceptually distinct animal models: the elevated plus maze (EPM) and the Vogel conflict test (VCT). We observed that drugs which interfere with ECB reuptake/metabolism in both the PL and in the dentate gyrus of the dHIP induced anxiolytic-like effect, in both the EPM and in the VCT via CB1 receptors, suggesting that CB1 signaling in these brain regions modulates defensive responses to both innate and learned threatening stimuli. This data further strengthens previous results indicating modulation of hippocampal and MPFC activity via CB1 by ECBs, which could be therapeutically targeted to treat anxiety disorders.

  17. Native CB1 receptor affinity, intrinsic activity and accumbens shell dopamine stimulant properties of third generation SPICE/K2 cannabinoids: BB-22, 5F-PB-22, 5F-AKB-48 and STS-135.

    Science.gov (United States)

    De Luca, Maria Antonietta; Castelli, M Paola; Loi, Barbara; Porcu, Alessandra; Martorelli, Mariella; Miliano, Cristina; Kellett, Kathryn; Davidson, Colin; Stair, Jacqueline L; Schifano, Fabrizio; Di Chiara, Gaetano

    2016-06-01

    In order to investigate the in vivo dopamine (DA) stimulant properties of selected 3rd generation Spice/K2 cannabinoids, BB-22, 5F-PB-22, 5F-AKB-48 and STS-135, their in vitro affinity and agonist potency at native rat and mice CB1 receptors was studied. The compounds bind with high affinity to CB1 receptors in rat cerebral cortex homogenates and stimulate CB1-induced [(35)S]GTPγS binding with high potency and efficacy. BB-22 and 5F-PB-22 showed the lowest Ki of binding to CB1 receptors (0.11 and 0.13 nM), i.e., 30 and 26 times lower respectively than that of JWH-018 (3.38 nM), and a potency (EC50, 2.9 and 3.7 nM, respectively) and efficacy (Emax, 217% and 203%, respectively) as CB1 agonists higher than JWH-018 (EC50, 20.2 nM; Emax, 163%). 5F-AKB-48 and STS-135 had higher Ki for CB1 binding, higher EC50 and lower Emax as CB1 agonists than BB-22 and 5F-PB-22 but still comparatively more favourable than JWH-018. The agonist properties of all the compounds were abolished or drastically reduced by the CB1 antagonist/inverse agonist AM251 (0.1 μM). No activation of G-protein was observed in CB1-KO mice. BB-22 (0.003-0.01 mg/kg i.v.) increased dialysate DA in the accumbens shell but not in the core or in the medial prefrontal cortex, with a bell shaped dose-response curve and an effect at 0.01 mg/kg and a biphasic time-course. Systemic AM251 (1.0 mg/kg i.p.) completely prevented the stimulant effect of BB-22 on dialysate DA in the NAc shell. All the other compounds increased dialysate DA in the NAc shell at doses consistent with their in vitro affinity for CB1 receptors (5F-PB-22, 0.01 mg/kg; 5F-AKB-48, 0.1 mg/kg; STS-135, 0.15 mg/kg i.v.). 3rd generation cannabinoids can be even more potent and super-high CB1 receptor agonists compared to JWH-018. Future research will try to establish if these properties can explain the high toxicity and lethality associated with these compounds.

  18. Structural dynamics and energetics underlying allosteric inactivation of the cannabinoid receptor CB1.

    Science.gov (United States)

    Fay, Jonathan F; Farrens, David L

    2015-07-01

    G protein-coupled receptors (GPCRs) are surprisingly flexible molecules that can do much more than simply turn on G proteins. Some even exhibit biased signaling, wherein the same receptor preferentially activates different G-protein or arrestin signaling pathways depending on the type of ligand bound. Why this behavior occurs is still unclear, but it can happen with both traditional ligands and ligands that bind allosterically outside the orthosteric receptor binding pocket. Here, we looked for structural mechanisms underlying these phenomena in the marijuana receptor CB1. Our work focused on the allosteric ligand Org 27569, which has an unusual effect on CB1-it simultaneously increases agonist binding, decreases G--protein activation, and induces biased signaling. Using classical pharmacological binding studies, we find that Org 27569 binds to a unique allosteric site on CB1 and show that it can act alone (without need for agonist cobinding). Through mutagenesis studies, we find that the ability of Org 27569 to bind is related to how much receptor is in an active conformation that can couple with G protein. Using these data, we estimated the energy differences between the inactive and active states. Finally, site-directed fluorescence labeling studies show the CB1 structure stabilized by Org 27569 is different and unique from that stabilized by antagonist or agonist. Specifically, transmembrane helix 6 (TM6) movements associated with G-protein activation are blocked, but at the same time, helix 8/TM7 movements are enhanced, suggesting a possible mechanism for the ability of Org 27569 to induce biased signaling.

  19. Discovery of potent and selective nonsteroidal indazolyl amide glucocorticoid receptor agonists.

    Science.gov (United States)

    Sheppeck, James E; Gilmore, John L; Xiao, Hai-Yun; Dhar, T G Murali; Nirschl, David; Doweyko, Arthur M; Sack, Jack S; Corbett, Martin J; Malley, Mary F; Gougoutas, Jack Z; Mckay, Lorraine; Cunningham, Mark D; Habte, Sium F; Dodd, John H; Nadler, Steven G; Somerville, John E; Barrish, Joel C

    2013-10-01

    Modification of a phenolic lead structure based on lessons learned from increasing the potency of steroidal glucocorticoid agonists lead to the discovery of exceptionally potent, nonsteroidal, indazole GR agonists. SAR was developed to achieve good selectivity against other nuclear hormone receptors with the ultimate goal of achieving a dissociated GR agonist as measured by human in vitro assays. The specific interactions by which this class of compounds inhibits GR was elucidated by solving an X-ray co-crystal structure. PMID:23953070

  20. Neuron to astrocyte communication via cannabinoid receptors is necessary for sustained epileptiform activity in rat hippocampus.

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    Guyllaume Coiret

    Full Text Available Astrocytes are integral functional components of synapses, regulating transmission and plasticity. They have also been implicated in the pathogenesis of epilepsy, although their precise roles have not been comprehensively characterized. Astrocytes integrate activity from neighboring synapses by responding to neuronally released neurotransmitters such as glutamate and ATP. Strong activation of astrocytes mediated by these neurotransmitters can promote seizure-like activity by initiating a positive feedback loop that induces excessive neuronal discharge. Recent work has demonstrated that astrocytes express cannabinoid 1 (CB1 receptors, which are sensitive to endocannabinoids released by nearby pyramidal cells. In this study, we tested whether this mechanism also contributes to epileptiform activity. In a model of 4-aminopyridine induced epileptic-like activity in hippocampal slice cultures, we show that pharmacological blockade of astrocyte CB1 receptors did not modify the initiation, but significantly reduced the maintenance of epileptiform discharge. When communication in astrocytic networks was disrupted by chelating astrocytic calcium, this CB1 receptor-mediated modulation of epileptiform activity was no longer observed. Thus, endocannabinoid signaling from neurons to astrocytes represents an additional significant factor in the maintenance of epileptiform activity in the hippocampus.

  1. Electroacupuncture Inhibition of Hyperalgesia in Rats with Adjuvant Arthritis: Involvement of Cannabinoid Receptor 1 and Dopamine Receptor Subtypes in Striatum

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    Yin Shou

    2013-01-01

    Full Text Available Electroacupuncture (EA has been regarded as an alternative treatment for inflammatory pain for several decades. However, the molecular mechanisms underlying the antinociceptive effect of EA have not been thoroughly clarified. Previous studies have shown that cannabinoid CB1 receptors are related to pain relief. Accumulating evidence has shown that the CB1 and dopamine systems sometimes interact and may operate synergistically in rat striatum. To our knowledge, dopamine D1/D2 receptors are involved in EA analgesia. In this study, we found that repeated EA at Zusanli (ST36 and Kunlun (BL60 acupoints resulted in marked improvements in thermal hyperalgesia. Both western blot assays and FQ-PCR analysis results showed that the levels of CB1 expression in the repeated-EA group were much higher than those in any other group (P=0.001. The CB1-selective antagonist AM251 inhibited the effects of repeated EA by attenuating the increases in CB1 expression. The two kinds of dopamine receptors imparted different actions on the EA-induced CB1 upregulation in AA rat model. These results suggested that the strong activation of the CB1 receptor after repeated EA resulted in the concomitant phenomenon of the upregulation of D1 and D2 levels of gene expression.

  2. Stereostructure-activity studies on agonists at the AMPA and kainate subtypes of ionotropic glutamate receptors

    DEFF Research Database (Denmark)

    Johansen, Tommy N; Greenwood, Jeremy R; Frydenvang, Karla Andrea;

    2003-01-01

    -methyl-4-isoxazolyl)propionic acid (AMPA) receptor subtype of ionotropic Glu receptors in the presence or absence of an agonist has provided important information about ligand-receptor interaction mechanisms. The availability of these binding domain crystal structures has formed the basis for rational...... design of ligands, especially for the AMPA and kainate subtypes of ionotropic Glu receptors. This mini-review will focus on structure-activity relationships on AMPA and kainate receptor agonists with special emphasis on stereochemical and three-dimensional aspects....

  3. Identification of Ecdysone Hormone Receptor Agonists as a Therapeutic Approach for Treating Filarial Infections

    Science.gov (United States)

    Mhashilkar, Amruta S.; Vankayala, Sai L.; Liu, Canhui; Kearns, Fiona; Mehrotra, Priyanka; Tzertzinis, George; Palli, Subba R.; Woodcock, H. Lee; Unnasch, Thomas R.

    2016-01-01

    Background A homologue of the ecdysone receptor has previously been identified in human filarial parasites. As the ecdysone receptor is not found in vertebrates, it and the regulatory pathways it controls represent attractive potential chemotherapeutic targets. Methodology/ Principal Findings Administration of 20-hydroxyecdysone to gerbils infected with B. malayi infective larvae disrupted their development to adult stage parasites. A stable mammalian cell line was created incorporating the B. malayi ecdysone receptor ligand-binding domain, its heterodimer partner and a secreted luciferase reporter in HEK293 cells. This was employed to screen a series of ecdysone agonist, identifying seven agonists active at sub-micromolar concentrations. A B. malayi ecdysone receptor ligand-binding domain was developed and used to study the ligand-receptor interactions of these agonists. An excellent correlation between the virtual screening results and the screening assay was observed. Based on both of these approaches, steroidal ecdysone agonists and the diacylhydrazine family of compounds were identified as a fruitful source of potential receptor agonists. In further confirmation of the modeling and screening results, Ponasterone A and Muristerone A, two compounds predicted to be strong ecdysone agonists stimulated expulsion of microfilaria and immature stages from adult parasites. Conclusions The studies validate the potential of the B. malayi ecdysone receptor as a drug target and provide a means to rapidly evaluate compounds for development of a new class of drugs against the human filarial parasites. PMID:27300294

  4. Delta(9)-tetrahydrocannabinol prolongs the immobility time in the mouse forced swim test: involvement of cannabinoid CB(1) receptor and serotonergic system.

    Science.gov (United States)

    Egashira, Nobuaki; Matsuda, Tomomi; Koushi, Emi; Higashihara, Fuminori; Mishima, Kenichi; Chidori, Shozo; Hasebe, Nobuyoshi; Iwasaki, Katsunori; Nishimura, Ryoji; Oishi, Ryozo; Fujiwara, Michihiro

    2008-07-28

    In the present study, we investigated the effect of Delta(9)-tetrahydrocannabinol (THC), the principal psychoactive component of marijuana, on immobility time during the forced swim test. THC (2 and 6 mg/kg, i.p.) significantly prolonged the immobility time. In addition, THC at the same doses did not significantly affect locomotor activity in the open-field test. The selective cannabinoid CB(1) receptor antagonist rimonabant (3 mg/kg, i.p.) significantly reduced the enhancement of immobility by THC (6 mg/kg). Similarly, the selective serotonin (5-HT) reuptake inhibitor (SSRI) citalopram (10 mg/kg, i.p.) and 5-HT(1A/7) receptor agonist 8-hydroxy-2-(di-n-propylamino) tetralin (8-OH-DPAT, 0.3 mg/kg, i.p.) significantly reduced this THC-induced effect. Moreover, the selective 5-HT(1A) receptor antagonist N-[2-[4-(2-methoxyphenyl)-1-piperazinyl]ethyl]-N-(2-pyridinyl) cyclohexane carboxamide dihydrochloride (WAY100635, 1 mg/kg, i.p.) and the postsynaptic 5-HT(1A) receptor antagonist MM-77 (0.1 mg/kg, i.p.) reversed this reduction effect of 8-OH-DPAT (0.3 mg/kg). In contrast, the selective 5-HT(7) receptor antagonist (R)-3-[2-[2-(4-methylpiperidin-1-yl)ethyl]pyrrolidine-1-sulfonyl]phenol hydrochloride (SB269970) had no effect on this reduction effect of 8-OH-DPAT. WAY100635 (1 mg/kg) also reversed the reduction effect of citalopram (10 mg/kg). These findings suggest that the 5-HT(1A) receptors are involved in THC-induced enhancement of immobility.

  5. Effect of the CB1 cannabinoid agonist WIN 55212-2 on the acquisition and reinstatement of MDMA-induced conditioned place preference in mice

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    Miñarro José

    2010-03-01

    Full Text Available Abstract Background Numerous reports indicate that MDMA users consume other psychoactive drugs, among which cannabis is one of the most common. The aim of the present study was to evaluate, using the conditioned place preference, the effect of the cannabinoid agonist WIN 55,212-2 on the rewarding effects of MDMA in mice. Methods In the first experiment adolescent mice were initially conditioned with 1.25, 2.5 or 5 mg/kg of MDMA or 0.1 or 0.5 mg/kg of WIN and subsequently with both drugs. Reinstatement of the extinguished preference by priming doses was performed in the groups that showed CPP. In the second experiment, animals were conditioned with 2.5 or 5 mg/kg of MDMA and, after extinction, reinstatement of the preference was induced by 0.5 or 0.1 mg/kg of WIN. Results A low dose of WIN 55212-2 (0.1 mg/kg increased the rewarding effects of low doses of MDMA (1.25 mg/kg, although a decrease in the preference induced by MDMA (5 and 2.5 mg/kg was observed when the dose of WIN 55212-2 was raised (0.5 mg/kg. The CB1 antagonist SR 141716 also increased the rewarding effects of the lowest MDMA dose and did not block the effects of WIN. Animals treated with the highest WIN dose plus a non-neurotoxic dose of MDMA exhibited decreases of striatal DA and serotonin in the cortex. On the other hand, WIN 55212-2-induced CPP was reinstated by priming injections of MDMA, although WIN did not reinstate the MDMA-induced CPP. Conclusions These results confirm that the cannabinoid system plays a role in the rewarding effects of MDMA and highlights the risks that sporadic drug use can pose in terms of relapse to dependence. Finally, the potential neuroprotective action of cannabinoids is not supported by our data; on the contrary, they are evidence of the potential neurotoxic effect of said drugs when administered with MDMA.

  6. Rational design of orally-active, pyrrolidine-based progesterone receptor partial agonists

    Energy Technology Data Exchange (ETDEWEB)

    Thompson, Scott K.; Washburn, David G.; Frazee, James S.; Madauss, Kevin P.; Hoang, Tram H.; Lapinski, Leahann; Grygielko, Eugene T.; Glace, Lindsay E.; Trizna, Walter; Williams, Shawn P.; Duraiswami, Chaya; Bray, Jeffrey D.; Laping, Nicholas J.; (GSKNC); (GSKPA)

    2010-09-03

    Using the X-ray crystal structure of an amide-based progesterone receptor (PR) partial agonist bound to the PR ligand binding domain, a novel PR partial agonist class containing a pyrrolidine ring was designed. Members of this class of N-alkylpyrrolidines demonstrate potent and highly selective partial agonism of the progesterone receptor, and one of these analogs was shown to be efficacious upon oral dosing in the OVX rat model of estrogen opposition.

  7. The influence of cannabinoids on learning and memory processes of the dorsal striatum.

    Science.gov (United States)

    Goodman, Jarid; Packard, Mark G

    2015-11-01

    Extensive evidence indicates that the mammalian endocannabinoid system plays an integral role in learning and memory. Our understanding of how cannabinoids influence memory comes predominantly from studies examining cognitive and emotional memory systems mediated by the hippocampus and amygdala, respectively. However, recent evidence suggests that cannabinoids also affect habit or stimulus-response (S-R) memory mediated by the dorsal striatum. Studies implementing a variety of maze tasks in rats indicate that systemic or intra-dorsolateral striatum infusions of cannabinoid receptor agonists or antagonists impair habit memory. In mice, cannabinoid 1 (CB1) receptor knockdown can enhance or impair habit formation, whereas Δ(9)THC tolerance enhances habit formation. Studies in human cannabis users also suggest an enhancement of S-R/habit memory. A tentative conclusion based on the available data is that acute disruption of the endocannabinoid system with either agonists or antagonists impairs, whereas chronic cannabinoid exposure enhances, dorsal striatum-dependent S-R/habit memory. CB1 receptors are required for multiple forms of striatal synaptic plasticity implicated in memory, including short-term and long-term depression. Interactions with the hippocampus-dependent memory system may also have a role in some of the observed effects of cannabinoids on habit memory. The impairing effect often observed with acute cannabinoid administration argues for cannabinoid-based treatments for human psychopathologies associated with a dysfunctional habit memory system (e.g. post-traumatic stress disorder and drug addiction/relapse). In addition, the enhancing effect of repeated cannabinoid exposure on habit memory suggests a novel neurobehavioral mechanism for marijuana addiction involving the dorsal striatum-dependent memory system. PMID:26092091

  8. Prolonging survival of corneal transplantation by selective sphingosine-1-phosphate receptor 1 agonist.

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    Min Gao

    Full Text Available Corneal transplantation is the most used therapy for eye disorders. Although the cornea is somewhat an immune privileged organ, immune rejection is still the major problem that reduces the success rate. Therefore, effective chemical drugs that regulate immunoreactions are needed to improve the outcome of corneal transplantations. Here, a sphingosine-1-phosphate receptor 1 (S1P1 selective agonist was systematically evaluated in mouse allogeneic corneal transplantation and compared with the commonly used immunosuppressive agents. Compared with CsA and the non-selective sphingosine 1-phosphate (S1P receptor agonist FTY720, the S1P1 selective agonist can prolong the survival corneal transplantation for more than 30 days with a low immune response. More importantly, the optimal dose of the S1P1 selective agonist was much less than non-selective S1P receptor agonist FTY720, which would reduce the dose-dependent toxicity in drug application. Then we analyzed the mechanisms of the selected S1P1 selective agonist on the immunosuppression. The results shown that the S1P1 selective agonist could regulate the distribution of the immune cells with less CD4+ T cells and enhanced Treg cells in the allograft, moreover the expression of anti-inflammatory cytokines TGF-β1 and IL-10 unregulated which can reduce the immunoreactions. These findings suggest that S1P1 selective agonist may be a more appropriate immunosuppressive compound to effectively prolong mouse allogeneic corneal grafts survival.

  9. Human orexin/hypocretin receptors form constitutive homo- and heteromeric complexes with each other and with human CB{sub 1} cannabinoid receptors

    Energy Technology Data Exchange (ETDEWEB)

    Jäntti, Maria H., E-mail: maria.jantti@helsinki.fi [Department of Veterinary Biosciences, POB 66, FIN-00014 University of Helsinki (Finland); Mandrika, Ilona, E-mail: ilona@biomed.lu.lv [Latvian Biomedical Research and Study Centre, Ratsupites Str. 1, Riga LV 1067 (Latvia); Kukkonen, Jyrki P., E-mail: jyrki.kukkonen@helsinki.fi [Department of Veterinary Biosciences, POB 66, FIN-00014 University of Helsinki (Finland)

    2014-03-07

    Highlights: • OX{sub 1} and OX{sub 2} orexin and CB{sub 1} cannabinoid receptor dimerization was investigated. • Bioluminescence resonance energy transfer method was used. • All receptors readily formed constitutive homo- and heteromeric complexes. - Abstract: Human OX{sub 1} orexin receptors have been shown to homodimerize and they have also been suggested to heterodimerize with CB{sub 1} cannabinoid receptors. The latter has been suggested to be important for orexin receptor responses and trafficking. In this study, we wanted to assess the ability of the other combinations of receptors to also form similar complexes. Vectors for expression of human OX{sub 1}, OX{sub 2} and CB{sub 1} receptors, C-terminally fused with either Renilla luciferase or GFP{sup 2} green fluorescent protein variant, were generated. The constructs were transiently expressed in Chinese hamster ovary cells, and constitutive dimerization between the receptors was assessed by bioluminescence energy transfer (BRET). Orexin receptor subtypes readily formed homo- and hetero(di)mers, as suggested by significant BRET signals. CB{sub 1} receptors formed homodimers, and they also heterodimerized with both orexin receptors. Interestingly, BRET efficiency was higher for homodimers than for almost all heterodimers. This is likely to be due to the geometry of the interaction; the putatively symmetric dimers may place the C-termini in a more suitable orientation in homomers. Fusion of luciferase to an orexin receptor and GFP{sup 2} to CB{sub 1} produced more effective BRET than the opposite fusions, also suggesting differences in geometry. Similar was seen for the OX{sub 1}–OX{sub 2} interaction. In conclusion, orexin receptors have a significant propensity to make homo- and heterodi-/oligomeric complexes. However, it is unclear whether this affects their signaling. As orexin receptors efficiently signal via endocannabinoid production to CB{sub 1} receptors, dimerization could be an effective way

  10. O-2050 facilitates noradrenaline release and increases the CB1 receptor inverse agonistic effect of rimonabant in the guinea pig hippocampus.

    Science.gov (United States)

    Jergas, Bernd; Schulte, Kirsten; Bindila, Laura; Lutz, Beat; Schlicker, Eberhard

    2014-07-01

    The cannabinoid CB1 receptors on the noradrenergic neurons in guinea pig hippocampal slices show an endogenous endocannabinoid tone. This conclusion is based on rimonabant, the facilitatory effect of which on noradrenaline release might be due to its inverse CB1 receptor agonism and/or the interruption of a tonic inhibition elicited by endocannabinoids. To examine the latter mechanism, a neutral antagonist would be suitable. Therefore, we studied whether O-2050 is a neutral CB1 receptor antagonist in the guinea pig hippocampus and whether it mimics the facilitatory effect of rimonabant. CB1 receptor affinity of O-2050 was quantified in cerebrocortical membranes, using (3)H-rimonabant binding. Its CB1 receptor potency and effect on (3)H-noradrenaline release were determined in superfused hippocampal slices. Its intrinsic activity at CB1 receptors was studied in hippocampal membranes, using (35)S-GTPγS binding. Endocannabinoid levels in hippocampus were determined by liquid chromatography-multiple reaction monitoring. O-2050 was about ten times less potent than rimonabant in its CB1 receptor affinity, potency and facilitatory effect on noradrenaline release. Although not affecting (35)S-GTPγS binding by itself, O-2050 shifted the concentration-response curve of a CB1 receptor agonist to the right but that of rimonabant to the left. Levels of anandamide and 2-arachidonoyl glycerol in guinea pig hippocampus closely resembled those in mouse hippocampus. In conclusion, our results with O-2050 confirm that the CB1 receptors on noradrenergic neurons of the guinea pig hippocampus show an endogenous tone. To differentiate between the two mechanisms leading to an endogenous tone, O-2050 is not superior to rimonabant since O-2050 may increase the inverse agonistic effect of endocannabinoids.

  11. In vivo delta opioid receptor internalization controls behavioral effects of agonists.

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    Amynah A A Pradhan

    Full Text Available BACKGROUND: GPCRs regulate a remarkable diversity of biological functions, and are thus often targeted for drug therapies. Stimulation of a GPCR by an extracellular ligand triggers receptor signaling via G proteins, and this process is highly regulated. Receptor activation is typically accompanied by desensitization of receptor signaling, a complex feedback regulatory process of which receptor internalization is postulated as a key event. The in vivo significance of GPCR internalization is poorly understood. In fact, the majority of studies have been performed in transfected cell systems, which do not adequately model physiological environments and the complexity of integrated responses observed in the whole animal. METHODS AND FINDINGS: In this study, we used knock-in mice expressing functional fluorescent delta opioid receptors (DOR-eGFP in place of the native receptor to correlate receptor localization in neurons with behavioral responses. We analyzed the pain-relieving effects of two delta receptor agonists with similar signaling potencies and efficacies, but distinct internalizing properties. An initial treatment with the high (SNC80 or low (AR-M100390 internalizing agonist equally reduced CFA-induced inflammatory pain. However, subsequent drug treatment produced highly distinct responses. Animals initially treated with SNC80 showed no analgesic response to a second dose of either delta receptor agonist. Concomitant receptor internalization and G-protein uncoupling were observed throughout the nervous system. This loss of function was temporary, since full DOR-eGFP receptor responses were restored 24 hours after SNC80 administration. In contrast, treatment with AR-M100390 resulted in retained analgesic response to a subsequent agonist injection, and ex vivo analysis showed that DOR-eGFP receptor remained G protein-coupled on the cell surface. Finally SNC80 but not AR-M100390 produced DOR-eGFP phosphorylation, suggesting that the two

  12. Preclinical evaluation and quantification of [18F]MK-9470 as a radioligand for PET imaging of the type 1 cannabinoid receptor in rat brain

    International Nuclear Information System (INIS)

    [18F]MK-9470 is an inverse agonist for the type 1 cannabinoid (CB1) receptor allowing its use in PET imaging. We characterized the kinetics of [18F]MK-9470 and evaluated its ability to quantify CB1 receptor availability in the rat brain. Dynamic small-animal PET scans with [18F]MK-9470 were performed in Wistar rats on a FOCUS-220 system for up to 10 h. Both plasma and perfused brain homogenates were analysed using HPLC to quantify radiometabolites. Displacement and blocking experiments were done using cold MK-9470 and another inverse agonist, SR141716A. The distribution volume (VT) of [18F]MK-9470 was used as a quantitative measure and compared to the use of brain uptake, expressed as SUV, a simplified method of quantification. The percentage of intact [18F]MK-9470 in arterial plasma samples was 80 ± 23 % at 10 min, 38 ± 30 % at 40 min and 13 ± 14 % at 210 min. A polar radiometabolite fraction was detected in plasma and brain tissue. The brain radiometabolite concentration was uniform across the whole brain. Displacement and pretreatment studies showed that 56 % of the tracer binding was specific and reversible. VT values obtained with a one-tissue compartment model plus constrained radiometabolite input had good identifiability (≤10 %). Ignoring the radiometabolite contribution using a one-tissue compartment model alone, i.e. without constrained radiometabolite input, overestimated the [18F]MK-9470 VT, but was correlated. A correlation between [18F]MK-9470 VT and SUV in the brain was also found (R 2 = 0.26-0.33; p ≤ 0.03). While the presence of a brain-penetrating radiometabolite fraction complicates the quantification of [18F]MK-9470 in the rat brain, its tracer kinetics can be modelled using a one-tissue compartment model with and without constrained radiometabolite input. (orig.)

  13. EFFECTS OF SYNTETIC CANNABINOID RECEPTOR LIGANDS WIN 55.212-2 AND ANANDAMID UPON IN VITRO ACTIVITY OF IMMUNOCOMPETENT CELLS

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    E. G. Lobanova

    2009-01-01

    Full Text Available Abstract. Ability of cannabinoid receptor ligands WIN 55.212-2 and anandamid to inhibit synthesis of TNFα and IL-8 was studied in healthy donors and men with allergic disorders. To establish mechanism of action for investigated substances, the selective antagonists of the СВ1-receptor (SR141716A and for СВ2 - receptor (SR144528 were applied. Studies with whole blood dilutions allowed of approximating in vivo conditions when investigating biological properties of WIN-55.212-2 and anandamid. The synthetic cannabinoids WIN - 55.212-2 and anandamid at a concentration of 3-10 μМ were capable of reducing synthesis of TNFα and IL-8 in lipopolysaccharide-stimulated blood leukocytes, both from healthy donors and subjects with allergic disorders. It was revealed that the antagonist of СВ1-receptor (SR141716A did not exert a receptor-mediated effect for WIN-55.212-2 and anandamid. Meanwhile, a СВ2-receptor antagonist (SR144528 entirely eliminated completely the blocking effect of anandamid and WIN-55.212-2.

  14. CB1 cannabinoid receptors are involved in neuroleptic-induced enhancement of brain neurotensin

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    Parichehr Hassanzadeh

    2014-03-01

    Full Text Available Objective(s: Targeting the neuropeptide systems has been shown to be useful for the development of more effective antipsychotic drugs. Neurotensin, an endogenous neuropeptide, appears to be involved in the mechanism of action of antipsychotics. However, the available data provide conflicting results and the mechanism(s by which antipsychotics affect brain neurotensin neurotransmission have not been identified. Therefore, we aimed to investigate the effects of fluphenazine and amisulpride on brain regional contents of neurotensin considering the role of cannabinoid CB1 receptors which interact with neurotensin neurotransmission. Materials and Methods:Fluphenazine (0.5, 1, and 3 mg/kg or amisulpride (3, 5, and 10 mg/kg were administered intraperitoneally to male Wistar rats either for one day or 28 consecutive days.Twenty four hours after the last injection of drug or vehicle, neurotensin contents were determined in the mesocorticolimbic and nigrostriatal dopamine regions by radioimmunoassay. In the case of any significant change, the effect of pre-treatment with CB1 receptor antagonist, AM251 was investigated. Results:Chronic, but not acute, treatment with the highest dose of fluphenazine or amisulpride resulted in significant enhancement of neurotensin contents in the prefronatal cortex and nucleus accumbens. Fluphenazine also elevated neurotensin levels in the anterior and posterior caudate nuclei and substantia nigra. Neither amisulpride nor fluphenazine affected neurotensin contents in the amygdala or hippocampus. Pre-treatment with AM251 (3 mg/kg prevented the neuroleptic-induced elevation of neurotensin. AM251 showed no effect by itself. Conclusion:The brain neurotensin under the regulatory action of CB1 receptors is involved in[T1]  the effects of amisulpride and fluphenazine.

  15. Differential Control of Cocaine Self-Administration by GABAergic and Glutamatergic CB1 Cannabinoid Receptors.

    Science.gov (United States)

    Martín-García, Elena; Bourgoin, Lucie; Cathala, Adeline; Kasanetz, Fernando; Mondesir, Miguel; Gutiérrez-Rodriguez, Ana; Reguero, Leire; Fiancette, Jean-François; Grandes, Pedro; Spampinato, Umberto; Maldonado, Rafael; Piazza, Pier Vincenzo; Marsicano, Giovanni; Deroche-Gamonet, Véronique

    2016-08-01

    The type 1 cannabinoid receptor (CB1) modulates numerous neurobehavioral processes and is therefore explored as a target for the treatment of several mental and neurological diseases. However, previous studies have investigated CB1 by targeting it globally, regardless of its two main neuronal localizations on glutamatergic and GABAergic neurons. In the context of cocaine addiction this lack of selectivity is critical since glutamatergic and GABAergic neuronal transmission is involved in different aspects of the disease. To determine whether CB1 exerts different control on cocaine seeking according to its two main neuronal localizations, we used mutant mice with deleted CB1 in cortical glutamatergic neurons (Glu-CB1) or in forebrain GABAergic neurons (GABA-CB1). In Glu-CB1, gene deletion concerns the dorsal telencephalon, including neocortex, paleocortex, archicortex, hippocampal formation and the cortical portions of the amygdala. In GABA-CB1, it concerns several cortical and non-cortical areas including the dorsal striatum, nucleus accumbens, thalamic, and hypothalamic nuclei. We tested complementary components of cocaine self-administration, separating the influence of primary and conditioned effects. Mechanisms underlying each phenotype were explored using in vivo microdialysis and ex vivo electrophysiology. We show that CB1 expression in forebrain GABAergic neurons controls mouse sensitivity to cocaine, while CB1 expression in cortical glutamatergic neurons controls associative learning processes. In accordance, in the nucleus accumbens, GABA-CB1 receptors control cocaine-induced dopamine release and Glu-CB1 receptors control AMPAR/NMDAR ratio; a marker of synaptic plasticity. Our findings demonstrate a critical distinction of the altered balance of Glu-CB1 and GABA-CB1 activity that could participate in the vulnerability to cocaine abuse and addiction. Moreover, these novel insights advance our understanding of CB1 neuropathophysiology.

  16. Differential Control of Cocaine Self-Administration by GABAergic and Glutamatergic CB1 Cannabinoid Receptors.

    Science.gov (United States)

    Martín-García, Elena; Bourgoin, Lucie; Cathala, Adeline; Kasanetz, Fernando; Mondesir, Miguel; Gutiérrez-Rodriguez, Ana; Reguero, Leire; Fiancette, Jean-François; Grandes, Pedro; Spampinato, Umberto; Maldonado, Rafael; Piazza, Pier Vincenzo; Marsicano, Giovanni; Deroche-Gamonet, Véronique

    2016-08-01

    The type 1 cannabinoid receptor (CB1) modulates numerous neurobehavioral processes and is therefore explored as a target for the treatment of several mental and neurological diseases. However, previous studies have investigated CB1 by targeting it globally, regardless of its two main neuronal localizations on glutamatergic and GABAergic neurons. In the context of cocaine addiction this lack of selectivity is critical since glutamatergic and GABAergic neuronal transmission is involved in different aspects of the disease. To determine whether CB1 exerts different control on cocaine seeking according to its two main neuronal localizations, we used mutant mice with deleted CB1 in cortical glutamatergic neurons (Glu-CB1) or in forebrain GABAergic neurons (GABA-CB1). In Glu-CB1, gene deletion concerns the dorsal telencephalon, including neocortex, paleocortex, archicortex, hippocampal formation and the cortical portions of the amygdala. In GABA-CB1, it concerns several cortical and non-cortical areas including the dorsal striatum, nucleus accumbens, thalamic, and hypothalamic nuclei. We tested complementary components of cocaine self-administration, separating the influence of primary and conditioned effects. Mechanisms underlying each phenotype were explored using in vivo microdialysis and ex vivo electrophysiology. We show that CB1 expression in forebrain GABAergic neurons controls mouse sensitivity to cocaine, while CB1 expression in cortical glutamatergic neurons controls associative learning processes. In accordance, in the nucleus accumbens, GABA-CB1 receptors control cocaine-induced dopamine release and Glu-CB1 receptors control AMPAR/NMDAR ratio; a marker of synaptic plasticity. Our findings demonstrate a critical distinction of the altered balance of Glu-CB1 and GABA-CB1 activity that could participate in the vulnerability to cocaine abuse and addiction. Moreover, these novel insights advance our understanding of CB1 neuropathophysiology. PMID:26612422

  17. Exercise reduces adipose tissue via cannabinoid receptor type 1 which is regulated by peroxisome proliferator-activated receptor

    International Nuclear Information System (INIS)

    Obesity is one major cardiovascular risk factor. We tested effects of endurance exercise on cannabinoid receptor type 1 (CB1) and peroxisome proliferator-activated receptor-δ (PPAR-δ)-dependent pathways in adipose tissue. Male Wistar rats were randomly assigned to standard laboratory chow or a high-fat diet without and with regular endurance exercise. Exercise in rats on high-fat diet significantly reduced visceral fat mass, blood pressure, and adipocyte size (each p < 0.05). Adipocyte hypertrophy induced by high-fat diet was accompanied by increased CB1 expression in adipose tissue, whereas exercise significantly reduced CB1 expression (each p < 0.05). CB1 receptor expression and adipocyte differentiation were directly regulated by PPAR-δ. Adipocyte hypertrophy induced by high-fat diet was accompanied by reduced PPAR-δ. Furthermore, selective silencing of PPAR-δ by RNA interference in 3T3-L1-preadipocyte cells significantly increased CB1 expression from 1.00 ± 0.06 (n = 3) to 1.91 ± 0.06 (n = 3; p < 0.01) and increased adipocyte differentiation, whereas adenovirus-mediated overexpression of PPAR-δ significantly reduced CB1 expression to 0.39 ± 0.03 (n = 3; p < 0.01) and reduced adipocyte differentiation. In the presence of the CB1 antagonist rimonabant adipocyte differentiation in stimulated 3T3 L1 preadipocyte cells was significantly reduced. The study indicates that high-fat diet-induced hypertrophy of adipocytes is associated with increased CB1 receptor expression which is directly regulated by PPAR-δ. Both CB1 and PPAR-δ are intimately involved in therapeutic interventions against a most important cardiovascular risk factor

  18. Dissociated sterol-based liver X receptor agonists as therapeutics for chronic inflammatory diseases.

    Science.gov (United States)

    Yu, Shan; Li, Sijia; Henke, Adam; Muse, Evan D; Cheng, Bo; Welzel, Gustav; Chatterjee, Arnab K; Wang, Danling; Roland, Jason; Glass, Christopher K; Tremblay, Matthew

    2016-07-01

    Liver X receptor (LXR), a nuclear hormone receptor, is an essential regulator of immune responses. Activation of LXR-mediated transcription by synthetic agonists, such as T0901317 and GW3965, attenuates progression of inflammatory disease in animal models. However, the adverse effects of these conventional LXR agonists in elevating liver lipids have impeded exploitation of this intriguing mechanism for chronic therapy. Here, we explore the ability of a series of sterol-based LXR agonists to alleviate inflammatory conditions in mice without hepatotoxicity. We show that oral treatment with sterol-based LXR agonists in mice significantly reduces dextran sulfate sodium colitis-induced body weight loss, which is accompanied by reduced expression of inflammatory markers in the large intestine. The anti-inflammatory property of these agonists is recapitulated in vitro in mouse lamina propria mononuclear cells, human colonic epithelial cells, and human peripheral blood mononuclear cells. In addition, treatment with LXR agonists dramatically suppresses inflammatory cytokine expression in a model of traumatic brain injury. Importantly, in both disease models, the sterol-based agonists do not affect the liver, and the conventional agonist T0901317 results in significant liver lipid accumulation and injury. Overall, these results provide evidence for the development of sterol-based LXR agonists as novel therapeutics for chronic inflammatory diseases.-Yu, S., Li, S., Henke, A., Muse, E. D., Cheng, B., Welzel, G., Chatterjee, A. K., Wang, D., Roland, J., Glass, C. K., Tremblay, M. Dissociated sterol-based liver X receptor agonists as therapeutics for chronic inflammatory diseases. PMID:27025962

  19. Cannabinoid type-1 receptors in the paraventricular nucleus of the hypothalamus inhibit stimulated food intake.

    Science.gov (United States)

    Soria-Gómez, E; Massa, F; Bellocchio, L; Rueda-Orozco, P E; Ciofi, P; Cota, D; Oliet, S H R; Prospéro-García, O; Marsicano, G

    2014-03-28

    Cannabinoid receptor type 1 (CB1)-dependent signaling in the brain is known to modulate food intake. Recent evidence has actually shown that CB1 can both inhibit and stimulate food intake in fasting/refeeding conditions, depending on the specific neuronal circuits involved. However, the exact brain sites where this bimodal control is exerted and the underlying neurobiological mechanisms are not fully understood yet. Using pharmacological and electrophysiological approaches, we show that local CB1 blockade in the paraventricular nucleus of the hypothalamus (PVN) increases fasting-induced hyperphagia in rats. Furthermore, local CB1 blockade in the PVN also increases the orexigenic effect of the gut hormone ghrelin in animals fed ad libitum. At the electrophysiological level, CB1 blockade in slices containing the PVN potentiates the decrease of the activity of PVN neurons induced by long-term application of ghrelin. Hence, the PVN is (one of) the site(s) where signals associated with the body's energy status determine the direction of the effects of endocannabinoid signaling on food intake.

  20. Hybrid inhibitor of peripheral cannabinoid-1 receptors and inducible nitric oxide synthase mitigates liver fibrosis

    Science.gov (United States)

    Liu, Ziyi; Cao, Zongxian; Jourdan, Tony; Erdelyi, Katalin; Godlewski, Grzegorz; Szanda, Gergő; Liu, Jie; Park, Joshua K.; Mukhopadhyay, Bani; Rosenberg, Avi Z.; Liow, Jeih-San; Lorenz, Robin G.; Pacher, Pal; Innis, Robert B.; Kunos, George

    2016-01-01

    Liver fibrosis, a consequence of chronic liver injury and a way station to cirrhosis and hepatocellular carcinoma, lacks effective treatment. Endocannabinoids acting via cannabinoid-1 receptors (CB1R) induce profibrotic gene expression and promote pathologies that predispose to liver fibrosis. CB1R antagonists produce opposite effects, but their therapeutic development was halted due to neuropsychiatric side effects. Inducible nitric oxide synthase (iNOS) also promotes liver fibrosis and its underlying pathologies, but iNOS inhibitors tested to date showed limited therapeutic efficacy in inflammatory diseases. Here, we introduce a peripherally restricted, orally bioavailable CB1R antagonist, which accumulates in liver to release an iNOS inhibitory leaving group. In mouse models of fibrosis induced by CCl4 or bile duct ligation, the hybrid CB1R/iNOS antagonist surpassed the antifibrotic efficacy of the CB1R antagonist rimonabant or the iNOS inhibitor 1400W, without inducing anxiety-like behaviors or CB1R occupancy in the CNS. The hybrid inhibitor also targeted CB1R-independent, iNOS-mediated profibrotic pathways, including increased PDGF, Nlrp3/Asc3, and integrin αvβ6 signaling, as judged by its ability to inhibit these pathways in cnr1−/− but not in nos2−/− mice. Additionally, it was able to slow fibrosis progression and to attenuate established fibrosis. Thus, dual-target peripheral CB1R/iNOS antagonists have therapeutic potential in liver fibrosis.

  1. Blockade of Cocaine or σ Receptor Agonist Self Administration by Subtype-Selective σ Receptor Antagonists.

    Science.gov (United States)

    Katz, Jonathan L; Hiranita, Takato; Kopajtic, Theresa A; Rice, Kenner C; Mesangeau, Christophe; Narayanan, Sanju; Abdelazeem, Ahmed H; McCurdy, Christopher R

    2016-07-01

    The identification of sigma receptor (σR) subtypes has been based on radioligand binding and, despite progress with σ1R cellular function, less is known about σR subtype functions in vivo. Recent findings that cocaine self administration experience will trigger σR agonist self administration was used in this study to assess the in vivo receptor subtype specificity of the agonists (+)-pentazocine, PRE-084 [2-(4-morpholinethyl) 1-phenylcyclohexanecarboxylate hydrochloride], and 1,3-di-o-tolylguanidine (DTG) and several novel putative σR antagonists. Radioligand binding studies determined in vitro σR selectivity of the novel compounds, which were subsequently studied for self administration and antagonism of cocaine, (+)-pentazocine, PRE-084, or DTG self administration. Across the dose ranges studied, none of the novel compounds were self administered, nor did they alter cocaine self administration. All compounds blocked DTG self administration, with a subset also blocking (+)-pentazocine and PRE-084 self administration. The most selective of the compounds in binding σ1Rs blocked cocaine self administration when combined with a dopamine transport inhibitor, either methylphenidate or nomifensine. These drug combinations did not decrease rates of responding maintained by food reinforcement. In contrast, the most selective of the compounds in binding σ2Rs had no effect on cocaine self administration in combination with either dopamine transport inhibitor. Thus, these results identify subtype-specific in vivo antagonists, and the utility of σR agonist substitution for cocaine self administration as an assay capable of distinguishing σR subtype selectivity in vivo. These results further suggest that effectiveness of dual σR antagonism and dopamine transport inhibition in blocking cocaine self administration is specific for σ1Rs and further support this dual targeting approach to development of cocaine antagonists. PMID:27189970

  2. Excitotoxic effects of non-NMDA receptor agonists in organotypic corticostriatal slice cultures

    DEFF Research Database (Denmark)

    Kristensen, B W; Noraberg, J; Jakobsen, B;

    1999-01-01

    The excitotoxic effects of the glutamate receptor agonists kainic acid (KA) and 2-amino-3-hydroxy-5-methyl-4-isoxazole propionate (AMPA) and the corresponding neuroprotective effects of the AMPA/KA receptor antagonist 2,3-dihydroxy-6-nitro-7-sulfamoyl-benzo(F)quinoxaline (NBQX) were examined...

  3. Systemic cancer immunotherapy with Toll-like receptor 7 agonists: Timing is everything.

    Science.gov (United States)

    Hotz, Christian; Bourquin, Carole

    2012-03-01

    Toll-like receptor (TLR) 7 agonists represent a promising strategy for the immunotherapy of cancer. We have recently investigated the influence of TLR tolerance on the efficacy of systemic tumor treatment with TLR7 ligands. We propose that considering the kinetics of receptor sensitivity highly improves the outcome of cancer immunotherapy. PMID:22720251

  4. Optimisation of in silico derived 2-aminobenzimidazole hits as unprecedented selective kappa opioid receptor agonists

    DEFF Research Database (Denmark)

    Sasmal, Pradip K; Krishna, C Vamsee; Sudheerkumar Adabala, S;

    2015-01-01

    Kappa opioid receptor (KOR) is an important mediator of pain signaling and it is targeted for the treatment of various pains. Pharmacophore based mining of databases led to the identification of 2-aminobenzimidazole derivative as KOR agonists with selectivity over the other opioid receptors DOR...

  5. In vivo and in vitro evaluation of novel μ-opioid receptor agonist compounds.

    Science.gov (United States)

    Nikaido, Yoshiaki; Kurosawa, Aya; Saikawa, Hitomi; Kuroiwa, Satoshi; Suzuki, Chiharu; Kuwabara, Nobuo; Hoshino, Hazime; Obata, Hideaki; Saito, Shigeru; Saito, Tamio; Osada, Hiroyuki; Kobayashi, Isao; Sezutsu, Hideki; Takeda, Shigeki

    2015-11-15

    Opioids are the most effective and widely used drugs for pain treatment. Morphine is an archetypal opioid and is an opioid receptor agonist. Unfortunately, the clinical usefulness of morphine is limited by adverse effects such as analgesic tolerance and addiction. Therefore, it is important to study the development of novel opioid agonists as part of pain control. The analgesic effects of opioids are mediated by three opioid receptors, namely opioid μ-, δ-, and κ-receptors. They belong to the G protein-coupled receptor superfamily and are coupled to Gi proteins. In the present study, we developed a ligand screening system to identify novel opioid μ-receptor agonists that measures [(35)S]GTPγS binding to cell membrane fractions prepared from the fat body of transgenic silkworms expressing μ-receptor-Gi1α fusion protein. We screened the RIKEN Natural Products Depository (NPDepo) chemical library, which contains 5848 compounds, and analogs of hit compounds. We successfully identified a novel, structurally unique compound, that we named GUM1, with agonist activity for the opioid μ-receptor (EC50 of 1.2 µM). The Plantar Test (Hargreaves' Method) demonstrated that subcutaneous injection of 3mg/kg of GUM1 into wild-type rats significantly extended latency time. This extension was also observed in a rat model of morphine tolerance and was inhibited by pre-treatment of naloxone. The unique molecular skeleton of GUM1 makes it an attractive molecule for further ligand-opioid receptor binding studies.

  6. Unraveling the high- and low-sensitivity agonist responses of nicotinic acetylcholine receptors

    DEFF Research Database (Denmark)

    Harpsøe, Kasper; Ahring, Philip K; Christensen, Jeppe K;

    2011-01-01

    The neuronal a4ß2 nicotinic acetylcholine receptors exist as two distinct subtypes, (a4)(2)(ß2)(3) and (a4)(3)(ß2)(2), and biphasic responses to acetylcholine and other agonists have been ascribed previously to coexistence of these two receptor subtypes. We offer a novel and radical explanation...

  7. Review of head-to-head comparisons of glucagon-like peptide-1 receptor agonists

    DEFF Research Database (Denmark)

    Madsbad, Sten

    2016-01-01

    Currently, six glucagon-like peptide-1 receptor agonists (GLP-1RAs) are approved for treating type 2 diabetes. These fall into two classes based on their receptor activation: short-acting exenatide twice daily and lixisenatide once daily; and longer-acting liraglutide once daily, exenatide once...

  8. Novel angiotensin type 2 (AT2) receptor agonists and uses thereof

    NARCIS (Netherlands)

    de Vries, L.; Nelemans, S.A.; Rink, R.; Roks, A.J.M.; Moll, G.N.

    2012-01-01

    The invention relates to novel pharmaceutically-useful peptides, in particular cyclic peptides that are agonists of the AngII type 2 receptor (AT2 receptor). The invention further relates to the use of such peptides as mecicaments, to pharmaceutical compositions containing them, and to their product

  9. γ-Hydroxybutyric acid (GHB is not an agonist of extrasynaptic GABAA receptors.

    Directory of Open Access Journals (Sweden)

    William M Connelly

    Full Text Available γ-Hydroxybutyric acid (GHB is an endogenous compound and a drug used clinically to treat the symptoms of narcolepsy. GHB is known to be an agonist of GABAB receptors with millimolar affinity, but also binds with much higher affinity to another site, known as the GHB receptor. While a body of evidence has shown that GHB does not bind to GABAA receptors widely, recent evidence has suggested that the GHB receptor is in fact on extrasynaptic α4β1δ GABAA receptors, where GHB acts as an agonist with an EC50 of 140 nM. We investigated three neuronal cell types that express a tonic GABAA receptor current mediated by extrasynaptic receptors: ventrobasal (VB thalamic neurons, dentate gyrus granule cells and striatal medium spiny neurons. Using whole-cell voltage clamp in brain slices, we found no evidence that GHB (10 µM induced any GABAA receptor mediated current in these cell types, nor that it modulated inhibitory synaptic currents. Furthermore, a high concentration of GHB (3 mM was able to produce a GABAB receptor mediated current, but did not induce any other currents. These results suggest either that GHB is not a high affinity agonist at native α4β1δ receptors, or that these receptors do not exist in classical areas associated with extrasynaptic currents.

  10. γ-Hydroxybutyric acid (GHB) is not an agonist of extrasynaptic GABAA receptors.

    Science.gov (United States)

    Connelly, William M; Errington, Adam C; Crunelli, Vincenzo

    2013-01-01

    γ-Hydroxybutyric acid (GHB) is an endogenous compound and a drug used clinically to treat the symptoms of narcolepsy. GHB is known to be an agonist of GABAB receptors with millimolar affinity, but also binds with much higher affinity to another site, known as the GHB receptor. While a body of evidence has shown that GHB does not bind to GABAA receptors widely, recent evidence has suggested that the GHB receptor is in fact on extrasynaptic α4β1δ GABAA receptors, where GHB acts as an agonist with an EC50 of 140 nM. We investigated three neuronal cell types that express a tonic GABAA receptor current mediated by extrasynaptic receptors: ventrobasal (VB) thalamic neurons, dentate gyrus granule cells and striatal medium spiny neurons. Using whole-cell voltage clamp in brain slices, we found no evidence that GHB (10 µM) induced any GABAA receptor mediated current in these cell types, nor that it modulated inhibitory synaptic currents. Furthermore, a high concentration of GHB (3 mM) was able to produce a GABAB receptor mediated current, but did not induce any other currents. These results suggest either that GHB is not a high affinity agonist at native α4β1δ receptors, or that these receptors do not exist in classical areas associated with extrasynaptic currents.

  11. Inhibition of monoacylglycerol lipase mediates a cannabinoid 1-receptor dependent delay of kindling progression in mice.

    Science.gov (United States)

    von Rüden, E L; Bogdanovic, R M; Wotjak, C T; Potschka, H

    2015-05-01

    Endocannabinoids, including 2-arachidonoylglycerol (2-AG), activate presynaptic cannabinoid type 1 receptors (CB1R) on inhibitory and excitatory neurons, resulting in a decreased release of neurotransmitters. The event-specific activation of the endocannabinoid system by inhibition of the endocannabinoid degrading enzymes may offer a promising strategy to selectively activate CB1Rs at the site of excessive neuronal activation with the overall goal to prevent the development epilepsy. The aim of this study was to investigate the impact of monoacylglycerol lipase (MAGL) inhibition on the development and progression of epileptic seizures in the kindling model of temporal lobe epilepsy. Therefore, we selectively blocked MAGL by JZL184 (8mg/kg, i.p.) in mice to analyze the effects of increased 2-AG levels on kindling acquisition and to exclude an anticonvulsive potential. Our results showed that JZL184 treatment significantly delayed the development of generalized seizures (p=0.0066) and decreased seizure (pkindling model of temporal lobe epilepsy, but caused only modest effects in fully kindled mice. Moreover, we proved that JZL184 treatment had no effects in conditional CB1R knockout mice lacking expression of the receptor in principle neurons of the forebrain. In conclusion, the data demonstrate that indirect CB1R agonism delays the development of generalized epileptic seizures but has no relevant acute anticonvulsive effects. Furthermore, we confirmed that the effects of JZL184 on kindling progression are CB1R mediated. Thus, the data indicate that the endocannabinoid 2-AG might be a promising target for an anti-epileptogenic approach.

  12. Pharmacological benefits of selective modulation of cannabinoid receptor type 2 (CB2) in experimental Alzheimer's disease.

    Science.gov (United States)

    Jayant, Shalini; Sharma, Brij Mohan; Bansal, Rani; Sharma, Bhupesh

    2016-01-01

    Alzheimer's disease (AD) is a progressive neurodegenerative disorder that pervasively affects the population across the world. Currently, there is no effective treatment available for this and existing drugs merely slow the progression of cognitive function decline. Thus, massive effort is required to find an intended therapeutic target to overcome this condition. The present study has been framed to investigate the ameliorative role of selective modulator of cannabinoid receptor type 2 (CB2), 1-phenylisatin in experimental AD condition. We have induced experimental AD in mice by using two induction models viz., intracerebroventricular (i.c.v.) administration of streptozotocin (STZ) and aluminum trichloride (AlCl3)+d-galactose. Morris water maze (MWM) and attentional set shifting test (ASST) were used to assess learning and memory. Hematoxylin-eosin and Congo red staining were used to examine the structural variation in brain. Brain oxidative stress (thiobarbituric acid reactive substance and glutathione), nitric oxide levels (nitrites/nitrates), acetyl cholinesterase activity, myeloperoxidase and calcium levels were also estimated. i.c.v. STZ as well as AlCl3+d-galactose have impaired spatial and reversal learning with executive functioning, increased brain oxidative and nitrosative stress, cholinergic activity, inflammation and calcium levels. Furthermore, these agents have also enhanced the burden of Aβ plaque in the brain. Treatment with 1-phenylisatin and donepezil attenuated i.c.v. STZ as well as AlCl3+d-galactose induced impairment of learning-memory, brain biochemistry and brain damage. Hence, this study concludes that CB2 receptor modulation can be a potential therapeutic target for the management of AD. PMID:26577751

  13. Exercise reduces adipose tissue via cannabinoid receptor type 1 which is regulated by peroxisome proliferator-activated receptor-delta.

    Science.gov (United States)

    Yan, Zhen Cheng; Liu, Dao Yan; Zhang, Li Li; Shen, Chen Yi; Ma, Qun Li; Cao, Ting Bing; Wang, Li Juan; Nie, Hai; Zidek, Walter; Tepel, Martin; Zhu, Zhi Ming

    2007-03-01

    Obesity is one major cardiovascular risk factor. We tested effects of endurance exercise on cannabinoid receptor type 1 (CB1) and peroxisome proliferator-activated receptor-delta (PPAR-delta)-dependent pathways in adipose tissue. Male Wistar rats were randomly assigned to standard laboratory chow or a high-fat diet without and with regular endurance exercise. Exercise in rats on high-fat diet significantly reduced visceral fat mass, blood pressure, and adipocyte size (each pAdipocyte hypertrophy induced by high-fat diet was accompanied by increased CB1 expression in adipose tissue, whereas exercise significantly reduced CB1 expression (each padipocyte differentiation were directly regulated by PPAR-delta. Adipocyte hypertrophy induced by high-fat diet was accompanied by reduced PPAR-delta. Furthermore, selective silencing of PPAR-delta by RNA interference in 3T3-L1-preadipocyte cells significantly increased CB1 expression from 1.00+/-0.06 (n=3) to 1.91+/-0.06 (n=3; padipocyte differentiation, whereas adenovirus-mediated overexpression of PPAR-delta significantly reduced CB1 expression to 0.39+/-0.03 (n=3; padipocyte differentiation. In the presence of the CB1 antagonist rimonabant adipocyte differentiation in stimulated 3T3 L1 preadipocyte cells was significantly reduced. The study indicates that high-fat diet-induced hypertrophy of adipocytes is associated with increased CB1 receptor expression which is directly regulated by PPAR-delta. Both CB1 and PPAR-delta are intimately involved in therapeutic interventions against a most important cardiovascular risk factor. PMID:17223076

  14. Lepidozenolide from the liverwort Lepidozia fauriana acts as a farnesoid X receptor agonist.

    Science.gov (United States)

    Lin, Hsiang-Ru

    2015-01-01

    Lepidozenolide is a sesquiterpenoid isolated from the liverwort Lepidozia fauriana and its possible bioactivity is unclear. The farnesoid X receptor (FXR) is a member of nuclear receptor superfamily that has been widely targeted for developing treatments for chronic liver disease and hyperglycemia. In this study, whether lepidozenolide may act as a FXR agonist was determined. Indeed, in mammalian one-hybrid and transient transfection reporter assays, lepidozenolide transactivated FXR to modulate promoter action including GAL4, CYP7A1, and PLTP promoters in a dose-dependent manner, while it exhibited slightly less agonistic activity than chenodeoxycholic acid, an endogenous FXR agonist. Through the molecular modeling docking studies lepidozenolide was shown to bind to FXR ligand binding pocket fairly well. All these results indicate that lepidozenolide acts as a FXR agonist. PMID:25315435

  15. PEROXISOME PROLIFERATOR-ACTIVATED RECEPTOR (PPAR) AGONISTS AS PROMISING NEW MEDICATIONS FOR DRUG ADDICTION: PRECLINICAL EVIDENCE

    Science.gov (United States)

    Foll, Bernard Le; Ciano, Patricia Di; Panlilio, Leigh V.; Goldberg, Steven R.; Ciccocioppo, Roberto

    2013-01-01

    This review examines the growing literature on the role of peroxisome proliferator-activated receptors (PPARs) in addiction. There are two subtypes of PPAR receptors that have been studied in addiction: PPAR-α and PPAR-γ. The role of each PPAR subtype in common models of addictive behavior, mainly pre-clinical models, is summarized. In particular, studies are reviewed that investigated the effects of PPAR-α agonists on relapse, sensitization, conditioned place preference, withdrawal and drug intake, and effects of PPAR-γ agonists on relapse, withdrawal and drug intake. Finally, studies that investigated the effects of PPAR agonists on neural pathways of addiction are reviewed. Taken together this preclinical data indicates that PPAR agonists are promising new medications for drug addiction treatment. PMID:23614675

  16. An amino-terminal variant of the central cannabinoid receptor resulting from alternative splicing.

    Science.gov (United States)

    Shire, D; Carillon, C; Kaghad, M; Calandra, B; Rinaldi-Carmona, M; Le Fur, G; Caput, D; Ferrara, P

    1995-02-24

    The cDNA sequences encoding the central cannabinoid receptor, CB1, are known for two species, rat and human. However, little information concerning the flanking, noncoding regions is presently available. We have isolated two overlapping clones from a human lung cDNA library with CB1 cDNA inserts. One of these, cann7, contains a short stretch of the CB1 coding region and 4 kilobase pairs (kb) of the 3'-untranslated region (UTR), including two polyadenylation signals. The other, cann6, is identical to cann7 upstream from the first polyadenylation signal, and in addition, it contains the whole coding region and extends for 1.8 kb into the 5'-UTR. Comparison of cann6 with the published sequence (Gérard, C. M., Mollereau, C., Vassart, G., and Parmentier, M. (1991) Biochem. J. 279, 129-134) shows the coding regions to be identical, but reveals important differences in the flanking regions. Notably, the cann6 sequence appears to be that of an immature transcript, containing 1.8 kb of an intronic sequence in the 5'-UTR. In addition, polymerase chain reaction amplification of the CB1 coding region in the IM-9 cell line cDNA resulted in two fragments, one containing the whole CB1 coding region and the second lacking a 167-base pair intron within the sequence encoding the amino-terminal tail of the receptor. This alternatively spliced form would translate to an NH2-terminal modified isoform (CB1A) of the receptor, shorter than CB1 by 61 amino acids. In addition, the first 28 amino acids of the putative truncated receptor are completely different from those of CB1, containing more hydrophobic residues. Rat CB1 mRNA is similarly alternatively spliced. A study of the distribution of the human CB1 and CB1A mRNAs by reverse transcription-polymerase chain reaction analysis showed the presence of both CB1 and CB1A throughout the brain and in all the peripheral tissues examined, with CB1A being present in amounts of up to 20% of CB1. PMID:7876112

  17. Effects of glucagon-like peptide-1 receptor agonists on renal function

    Institute of Scientific and Technical Information of China (English)

    Theodosios; D; Filippatos; Moses; S; Elisaf

    2013-01-01

    Glucagon-like peptide-1(GLP-1)receptor agonists result in greater improvements in glycemic control than placebo and promote weight loss with minimal hypoglycemia in patients with type 2 diabetes mellitus.A number of case reports show an association of GLP-1receptor agonists,mainly exenatide,with the development of acute kidney injury.The present review aims to present the available data regarding the effects of GLP-1 receptor agonists on renal function,their use in subjects with chronic renal failure and their possible association with acute kidney injury.Based on the current evidence,exenatide is eliminated by renal mechanisms and should not be given in patients with severe renal impairment or end stage renal disease.Liraglutide is not eliminated by renal or hepatic mechanisms,but it should be used with caution since there are only limited data in patients with renal or hepatic impairment.There is evidence from animal studies that GLP-1 receptor agonists exert protective role in diabetic nephropathy with mechanisms that seem to be independent of their glucose-lowering effect.Additionally,there is evidence that GLP-1 receptor agonists influence water and electrolyte balance.These effects may represent new ways to improve or even prevent diabetic nephropathy.

  18. Synthesis of Selective A3 and M1 Receptor Agonists

    OpenAIRE

    Snee, Stephen

    2011-01-01

    Detailed within this thesis is the synthesis of three A1 agonists which were designed by Muscagen using computational studies. The agonists are derived from condensation of the modified adenosine: (4S,6R)-6-(6-chloro-9H-purin-9-yl)-N,2,2-trimethyltetrahydrofuro[3,4-d][1,3]dioxole-4-carboxamide with novel heterocyclic primary amines.The amines 5-(aminomethyl)-N,N-diethyl-7-methyloxazolo[4,5-b]pyridin-2-amine, 5-(1-aminoethyl)-N,N,7-trimethyloxazolo[4,5-b]pyridin-2-amine and 5-(1-aminoethyl)-N,...

  19. Lack of Cocaine-Like Discriminative-Stimulus Effects of σ Receptor Agonists in Rats

    OpenAIRE

    Hiranita, Takato; Soto, Paul L; Tanda, Gianluigi; Katz, Jonathan L.

    2011-01-01

    Previous studies demonstrated effectiveness of selective sigma-receptor (σR) agonists (DTG, PRE-084) as reinforcers in rats trained to self-administer cocaine. Like cocaine, these drugs increased nucleus accumbens shell dopamine levels, and effects of DTG, but not PRE-084, on dopamine appeared to be mediated by σRs. Additionally, σR antagonists blocked self-administration of σR agonists, but were inactive against reinforcing and neurochemical effects of cocaine. Thus pharmacologically distinc...

  20. It's All in the Rhythm: The Role of Cannabinoids in Neural Oscillations and Psychosis.

    Science.gov (United States)

    Skosnik, Patrick D; Cortes-Briones, Jose A; Hajós, Mihály

    2016-04-01

    Evidence has accumulated over the past several decades suggesting that both exocannabinoids and endocannabinoids play a role in the pathophysiology of schizophrenia. The current article presents evidence suggesting that one of the mechanisms whereby cannabinoids induce psychosis is through the alteration in synchronized neural oscillations. Neural oscillations, particularly in the gamma (30-80 Hz) and theta (4-7 Hz) ranges, are disrupted in schizophrenia and are involved in various areas of perceptual and cognitive function. Regarding cannabinoids, preclinical evidence from slice and local field potential recordings has shown that central cannabinoid receptor (cannabinoid receptor type 1) agonists decrease the power of neural oscillations, particularly in the gamma and theta bands. Further, the administration of cannabinoids during critical stages of neural development has been shown to disrupt the brain's ability to generate synchronized neural oscillations in adulthood. In humans, studies examining the effects of chronic cannabis use (utilizing electroencephalography) have shown abnormalities in neural oscillations in a pattern similar to those observed in schizophrenia. Finally, recent studies in humans have also shown disruptions in neural oscillations after the acute administration of delta-9-tetrahydrocannabinol, the primary psychoactive constituent in cannabis. Taken together, these data suggest that both acute and chronic cannabinoids can disrupt the ability of the brain to generate synchronized oscillations at functionally relevant frequencies. Hence, this may represent one of the primary mechanisms whereby cannabinoids induce disruptions in attention, working memory, sensory-motor integration, and many other psychosis-related behavioral effects. PMID:26850792

  1. The cannabinoid quinol VCE-004.8 alleviates bleomycin-induced scleroderma and exerts potent antifibrotic effects through peroxisome proliferator-activated receptor-γ and CB2 pathways.

    Science.gov (United States)

    del Río, Carmen; Navarrete, Carmen; Collado, Juan A; Bellido, M Luz; Gómez-Cañas, María; Pazos, M Ruth; Fernández-Ruiz, Javier; Pollastro, Federica; Appendino, Giovanni; Calzado, Marco A; Cantarero, Irene; Muñoz, Eduardo

    2016-02-18

    Scleroderma is a group of rare diseases associated with early and transient inflammation and vascular injury, followed by fibrosis affecting the skin and multiple internal organs. Fibroblast activation is the hallmark of scleroderma, and disrupting the intracellular TGFβ signaling may provide a novel approach to controlling fibrosis. Because of its potential role in modulating inflammatory and fibrotic responses, both PPARγ and CB2 receptors represent attractive targets for the development of cannabinoid-based therapies. We have developed a non-thiophilic and chemically stable derivative of the CBD quinol (VCE-004.8) that behaves as a dual agonist of PPARγ and CB2 receptors, VCE-004.8 inhibited TGFβ-induced Col1A2 gene transcription and collagen synthesis. Moreover, VCE-004.8 inhibited TGFβ-mediated myofibroblast differentiation and impaired wound-healing activity. The anti-fibrotic efficacy in vivo was investigated in a murine model of dermal fibrosis induced by bleomycin. VCE-004.8 reduced dermal thickness, blood vessels collagen accumulation and prevented mast cell degranulation and macrophage infiltration in the skin. These effects were impaired by the PPARγ antagonist T0070907 and the CB2 antagonist AM630. In addition, VCE-004.8 downregulated the expression of several key genes associated with fibrosis, qualifying this semi-synthetic cannabinoid as a novel compound for the management of scleroderma and, potentially, other fibrotic diseases.

  2. Subchronic nicotine exposure in adolescence induces long-term effects on hippocampal and striatal cannabinoid-CB1 and mu-opioid receptors in rats.

    Science.gov (United States)

    Marco, Eva M; Granstrem, Oleg; Moreno, Enrique; Llorente, Ricardo; Adriani, Walter; Laviola, Giovanni; Viveros, Maria-Paz

    2007-02-14

    There is evidence for the existence of functional interactions between nicotine and cannabinoids and opioid compounds in adult experimental animals. However, there is scarce information about these relationships in young animals. In the present study we evaluated short and long-term effects of a subchronic nicotine treatment [0.4 mg/kg daily i.p. injections from postnatal day (PND) 34 to PND 43], upon hippocampal and striatal cannabinoid-CB(1) and mu-opioid receptors in Wistar rats of both genders. Rats were sacrificed 2 h after the last nicotine injection (short-term effects, PND 43) or one month later (long-term effects, PND 75). Hippocampal and striatal cannabinoid CB(1) and mu-opioid receptors were quantified by Western blotting. The subchronic nicotine treatment induced a region-dependent long-lasting effect in cannabinoid CB(1) receptor: a significant increase in hippocampal cannabinoid CB(1) receptors and a significant decrease in striatal cannabinoid CB(1) receptors, with these effects being similar in males and females. With respect to mu-opioid receptors, subchronic nicotine induced a significant down-regulation in hippocampal and striatal mu-opioid receptors in the long-term, and within the striatum the effects were more marked in adult males than in females. The present results indicate that juvenile nicotine taking may have implications for the endocannabinoid and endogenous opioid function and for the behaviors served by those systems, this includes possible modification of the response of adults to different psychotropic drugs, i.e. cannabis and morphine/heroin when taken later in life.

  3. Ligand-based receptor tyrosine kinase partial agonists: New paradigm for cancer drug discovery?

    Science.gov (United States)

    Riese, David J.

    2010-01-01

    Introduction Receptor tyrosine kinases (RTKs) are validated targets for oncology drug discovery and several RTK antagonists have been approved for the treatment of human malignancies. Nonetheless, the discovery and development of RTK antagonists has lagged behind the discovery and development of agents that target G-protein coupled receptors. In part, this is because it has been difficult to discover analogs of naturally-occurring RTK agonists that function as antagonists. Areas covered Here we describe ligands of ErbB receptors that function as partial agonists for these receptors, thereby enabling these ligands to antagonize the activity of full agonists for these receptors. We provide insights into the mechanisms by which these ligands function as antagonists. We discuss how information concerning these mechanisms can be translated into screens for novel small molecule- and antibody-based antagonists of ErbB receptors and how such antagonists hold great potential as targeted cancer chemotherapeutics. Expert opinion While there have been a number of important key findings into this field, the identification of the structural basis of ligand functional specificity is still of the greatest importance. While it is true that, with some notable exceptions, peptide hormones and growth factors have not proven to be good platforms for oncology drug discovery; addressing the fundamental issues of antagonistic partial agonists for receptor tyrosine kinases has the potential to steer oncology drug discovery in new directions. Mechanism based approaches are now emerging to enable the discovery of RTK partial agonists that may antagonize both agonist-dependent and –independent RTK signaling and may hold tremendous promise as targeted cancer chemotherapeutics. PMID:21532939

  4. The cannabinoid receptor agonist WIN55.212 reduces consequences of status epilepticus in rats

    NARCIS (Netherlands)

    Suleymanova, E.M.; Shangaraeva, V.A.; Rijn, C.M. van; Vinogradova, L.V.

    2016-01-01

    An acute brain insult can cause a spectrum of primary and secondary pathologies including increased risk for epilepsy, mortality and neurodegeneration. The endocannabinoid system, involved in protecting the brain against network hyperexcitability and excitotoxicity, is profoundly dysregulated by acu

  5. Alpha1 receptor coupling events initiated by methoxy-substituted tolazoline partial agonists

    International Nuclear Information System (INIS)

    A series of mono- and dimethyoxy substituted tolazoline derivatives, known to be partial agonists at the alpha1 receptor, were compared with the α1 selective full agonist phenylephrine (PE) on isolated strips of rabbit aorta Agonist activity was evaluated in contraction, 45Ca influx, 45Ca efflux, and 32P-Phospholipid labelling studies. Maximum contractile responses for the 2-, 3-, and 3, 5- methoxy substituted tolazoline derivatives (10-5M) were 53.8, 67.6 and 99.7% of the PE (10-5M) response respectively. These same partial agonists caused a stimulation of 45Ca influx to the extent of 64, 86, and 95% of the PE response respectively. In 45Ca efflux studies, (a measure of the intracellular Ca+2 release) the tolazolines caused: 30%, 63%, and 78% of the PE stimulated level. 32P-Phosphatidic acid (PA) labelling was measured as an index of PI turnover after α1 receptor stimulation. Compared to PE, the 2-, 3-, and 3,5- methoxy substituted tolazoline derivatives caused 22, 46, and 72% PA labelling. The above values are all in reasonable accord with the rank order or agonist activity shown in maximum contractile responses. The results of this investigation suggest that partial agonists stimulate α receptor coupling events at a level which is quantitatively comparable to their potencies in causing contraction of arterial smooth muscle

  6. Alpha/sub 1/ receptor coupling events initiated by methoxy-substituted tolazoline partial agonists

    Energy Technology Data Exchange (ETDEWEB)

    Wick, P.; Keung, A.; Deth, R.

    1986-03-01

    A series of mono- and dimethyoxy substituted tolazoline derivatives, known to be partial agonists at the alpha/sub 1/ receptor, were compared with the ..cap alpha../sub 1/ selective full agonist phenylephrine (PE) on isolated strips of rabbit aorta Agonist activity was evaluated in contraction, /sup 45/Ca influx, /sup 45/Ca efflux, and /sup 32/P-Phospholipid labelling studies. Maximum contractile responses for the 2-, 3-, and 3, 5- methoxy substituted tolazoline derivatives (10/sup -5/M) were 53.8, 67.6 and 99.7% of the PE (10/sup -5/M) response respectively. These same partial agonists caused a stimulation of /sup 45/Ca influx to the extent of 64, 86, and 95% of the PE response respectively. In /sup 45/Ca efflux studies, (a measure of the intracellular Ca/sup +2/ release) the tolazolines caused: 30%, 63%, and 78% of the PE stimulated level. /sup 32/P-Phosphatidic acid (PA) labelling was measured as an index of PI turnover after ..cap alpha../sub 1/ receptor stimulation. Compared to PE, the 2-, 3-, and 3,5- methoxy substituted tolazoline derivatives caused 22, 46, and 72% PA labelling. The above values are all in reasonable accord with the rank order or agonist activity shown in maximum contractile responses. The results of this investigation suggest that partial agonists stimulate ..cap alpha.. receptor coupling events at a level which is quantitatively comparable to their potencies in causing contraction of arterial smooth muscle.

  7. GLP-1 receptor agonists or DPP-4 inhibitors: how to guide the clinician?

    Science.gov (United States)

    Scheen, André J

    2013-12-01

    Pharmacological treatment of type 2 diabetes has been enriched during recent years, with the launch of incretin therapies targeting glucagon-like peptide-1 (GLP-1). Such medications comprise either GLP-1 receptor agonists, with short (one or two daily injections: exenatide, liraglutide, lixisenatide) or long duration (one injection once weekly: extended-released exenatide, albiglutide, dulaglutide, taspoglutide); or oral compounds inhibiting dipeptidyl peptidase-4 (DPP-4), the enzyme that inactives GLP-1, also called gliptins (sitagliptin, vildagliptin, saxagliptin, linagliptin, alogliptin). Although both pharmacological approaches target GLP-1, important differences exist concerning the mode of administration (subcutaneous injection versus oral ingestion), the efficacy (better with GLP-1 agonists), the effects on body weight and systolic blood pressure (diminution with agonists versus neutrality with gliptins), the tolerance profile (nausea and possibly vomiting with agonists) and the cost (higher with GLP-1 receptor agonists). Both agents may exert favourable cardiovascular effects. Gliptins may represent a valuable alternative to a sulfonylurea or a glitazone after failure of monotherapy with metformin while GLP-1 receptor agonists may be considered as a good alternative to insulin (especially in obese patients) after failure of a dual oral therapy. However, this scheme is probably too restrictive and modalities of using incretins are numerous, in almost all stages of type 2 diabetes. Physicians may guide the pharmacological choice based on clinical characteristics, therapeutic goals and patient's preference.

  8. Spatial Distribution of the Cannabinoid Type 1 and Capsaicin Receptors May Contribute to the Complexity of Their Crosstalk

    Science.gov (United States)

    Chen, Jie; Varga, Angelika; Selvarajah, Srikumaran; Jenes, Agnes; Dienes, Beatrix; Sousa-Valente, Joao; Kulik, Akos; Veress, Gabor; Brain, Susan D.; Baker, David; Urban, Laszlo; Mackie, Ken; Nagy, Istvan

    2016-01-01

    The cannabinoid type 1 (CB1) receptor and the capsaicin receptor (TRPV1) exhibit co-expression and complex, but largely unknown, functional interactions in a sub-population of primary sensory neurons (PSN). We report that PSN co-expressing CB1 receptor and TRPV1 form two distinct sub-populations based on their pharmacological properties, which could be due to the distribution pattern of the two receptors. Pharmacologically, neurons respond either only to capsaicin (COR neurons) or to both capsaicin and the endogenous TRPV1 and CB1 receptor ligand anandamide (ACR neurons). Blocking or deleting the CB1 receptor only reduces both anandamide- and capsaicin-evoked responses in ACR neurons. Deleting the CB1 receptor also reduces the proportion of ACR neurons without any effect on the overall number of capsaicin-responding cells. Regarding the distribution pattern of the two receptors, neurons express CB1 and TRPV1 receptors either isolated in low densities or in close proximity with medium/high densities. We suggest that spatial distribution of the CB1 receptor and TRPV1 contributes to the complexity of their functional interaction. PMID:27653550

  9. Free Fatty Acid Receptor 1 (FFA1/GPR40) Agonists

    DEFF Research Database (Denmark)

    Christiansen, Elisabeth; Due-Hansen, Maria E; Urban, Christian;

    2012-01-01

    FFA1 (GPR40) is a new target for treatment of type 2 diabetes. We recently identified the potent FFA1 agonist TUG-469 (5). Inspired by the structurally related TAK-875, we explored the effects of a mesylpropoxy appendage on 5. The appendage significantly lowers lipophilicity and improves metaboli...

  10. Beta-caryophyllene is a dietary cannabinoid

    Science.gov (United States)

    Gertsch, Jürg; Leonti, Marco; Raduner, Stefan; Racz, Ildiko; Chen, Jian-Zhong; Xie, Xiang-Qun; Altmann, Karl-Heinz; Karsak, Meliha; Zimmer, Andreas

    2008-01-01

    The psychoactive cannabinoids from Cannabis sativa L. and the arachidonic acid-derived endocannabinoids are nonselective natural ligands for cannabinoid receptor type 1 (CB1) and CB2 receptors. Although the CB1 receptor is responsible for the psychomodulatory effects, activation of the CB2 receptor is a potential therapeutic strategy for the treatment of inflammation, pain, atherosclerosis, and osteoporosis. Here, we report that the widespread plant volatile (E)-β-caryophyllene [(E)-BCP] selectively binds to the CB2 receptor (Ki = 155 ± 4 nM) and that it is a functional CB2 agonist. Intriguingly, (E)-BCP is a common constituent of the essential oils of numerous spice and food plants and a major component in Cannabis. Molecular docking simulations have identified a putative binding site of (E)-BCP in the CB2 receptor, showing ligand π–π stacking interactions with residues F117 and W258. Upon binding to the CB2 receptor, (E)-BCP inhibits adenylate cylcase, leads to intracellular calcium transients and weakly activates the mitogen-activated kinases Erk1/2 and p38 in primary human monocytes. (E)-BCP (500 nM) inhibits lipopolysaccharide (LPS)-induced proinflammatory cytokine expression in peripheral blood and attenuates LPS-stimulated Erk1/2 and JNK1/2 phosphorylation in monocytes. Furthermore, peroral (E)-BCP at 5 mg/kg strongly reduces the carrageenan-induced inflammatory response in wild-type mice but not in mice lacking CB2 receptors, providing evidence that this natural product exerts cannabimimetic effects in vivo. These results identify (E)-BCP as a functional nonpsychoactive CB2 receptor ligand in foodstuff and as a macrocyclic antiinflammatory cannabinoid in Cannabis. PMID:18574142

  11. Cannabinoid and Cholinergic Systems Interact during Performance of a Short-Term Memory Task in the Rat

    Science.gov (United States)

    Goonawardena, Anushka V.; Robinson, Lianne; Hampson, Robert E.; Riedel, Gernot

    2010-01-01

    It is now well established that cannabinoid agonists such as [delta][superscript 9]-tetrahydrocannabinol (THC), anandamide, and WIN 55,212-2 (WIN-2) produce potent and specific deficits in working memory (WM)/short-term memory (STM) tasks in rodents. Although mediated through activation of CB1 receptors located in memory-related brain regions such…

  12. Cannabinoid receptor-2 selective antagonist negatively regulates receptor activator of nuclear factor kappa B ligand mediated osteoclastogenesis

    Institute of Scientific and Technical Information of China (English)

    GENG De-chun; XU Yao-zeng; YANG Hui-lin; ZHU Guang-ming; WANG Xian-bin; ZHU Xue-song

    2011-01-01

    Background The cannabinoid receptor-2 (CB2) is important for bone remodeling. In this study, we investigated the effects of CB2 selective antagonist (AM630) on receptor activator of nuclear factor kappa B (RANK) ligand (RANKL)induced osteoclast differentiation and the underlying signaling pathway using a monocyte-macrophage cell line-RAW264.7.Methods RAW264.7 was cultured with RANKL for 6 days and then treated with AM630 for 24 hours. Mature osteoclasts were measured by tartrate-resistant acid phosphatase (TRAP) staining using a commercial kit. Total ribonucleic acid (RNA)was isolated and real-time reverse transcriptase-polymerase chain reaction (RT-PCR) was done to examine the expression of RANK, cathepsin K (CPK) and nuclear factor kappa B (NF-κB). The extracellular signal-regulated kinase (ERK),phosphorylation of ERK (P-ERK) and NF-κB production were tested by Western blotting. The effect of AM630 on RAW264.7 viability was determined using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazoliumbromide (MTT) assay.Results AM630 did not affect the viability of RAW264.7. However, this CB2 selective antagonist markedly inhibited osteoclast formation and the inhibition rate was dose-dependent. The dose of >100 nmol/L could reduce TRAP positive cells to the levels that were significantly lower than the control. AM630 suppressed the expression of genes associated with osteoclast differentiation and activation, such as RANK and CPK. An analysis of a signaling pathway showed that AM630 inhibited the RANKL-induced activation of ERK, but not NF-κB.Conclusion AM630 could inhibit the osteoclastogenesis from RAW264.7 induced with RANKL.

  13. The role of the cannabinoid receptor in adolescents' processing of facial expressions.

    Science.gov (United States)

    Ewald, Anais; Becker, Susanne; Heinrich, Angela; Banaschewski, Tobias; Poustka, Luise; Bokde, Arun; Büchel, Christian; Bromberg, Uli; Cattrell, Anna; Conrod, Patricia; Desrivières, Sylvane; Frouin, Vincent; Papadopoulos-Orfanos, Dimitri; Gallinat, Jürgen; Garavan, Hugh; Heinz, Andreas; Walter, Henrik; Ittermann, Bernd; Gowland, Penny; Paus, Tomáš; Martinot, Jean-Luc; Paillère Martinot, Marie-Laure; Smolka, Michael N; Vetter, Nora; Whelan, Rob; Schumann, Gunter; Flor, Herta; Nees, Frauke

    2016-01-01

    The processing of emotional faces is an important prerequisite for adequate social interactions in daily life, and might thus specifically be altered in adolescence, a period marked by significant changes in social emotional processing. Previous research has shown that the cannabinoid receptor CB1R is associated with longer gaze duration and increased brain responses in the striatum to happy faces in adults, yet, for adolescents, it is not clear whether an association between CBR1 and face processing exists. In the present study we investigated genetic effects of the two CB1R polymorphisms, rs1049353 and rs806377, on the processing of emotional faces in healthy adolescents. They participated in functional magnetic resonance imaging during a Faces Task, watching blocks of video clips with angry and neutral facial expressions, and completed a Morphed Faces Task in the laboratory where they looked at different facial expressions that switched from anger to fear or sadness or from happiness to fear or sadness, and labelled them according to these four emotional expressions. A-allele versus GG-carriers in rs1049353 displayed earlier recognition of facial expressions changing from anger to sadness or fear, but not for expressions changing from happiness to sadness or fear, and higher brain responses to angry, but not neutral, faces in the amygdala and insula. For rs806377 no significant effects emerged. This suggests that rs1049353 is involved in the processing of negative facial expressions with relation to anger in adolescence. These findings add to our understanding of social emotion-related mechanisms in this life period. PMID:26527537

  14. Variation in the human cannabinoid receptor CNR1 gene modulates gaze duration for happy faces

    Directory of Open Access Journals (Sweden)

    Chakrabarti Bhismadev

    2011-06-01

    Full Text Available Abstract Background From an early age, humans look longer at preferred stimuli and also typically look longer at facial expressions of emotion, particularly happy faces. Atypical gaze patterns towards social stimuli are common in autism spectrum conditions (ASC. However, it is unknown whether gaze fixation patterns have any genetic basis. In this study, we tested whether variations in the cannabinoid receptor 1 (CNR1 gene are associated with gaze duration towards happy faces. This gene was selected because CNR1 is a key component of the endocannabinoid system, which is involved in processing reward, and in our previous functional magnetic resonance imaging (fMRI study, we found that variations in CNR1 modulate the striatal response to happy (but not disgust faces. The striatum is involved in guiding gaze to rewarding aspects of a visual scene. We aimed to validate and extend this result in another sample using a different technique (gaze tracking. Methods A total of 30 volunteers (13 males and 17 females from the general population observed dynamic emotional expressions on a screen while their eye movements were recorded. They were genotyped for the identical four single-nucleotide polymorphisms (SNPs in the CNR1 gene tested in our earlier fMRI study. Results Two SNPs (rs806377 and rs806380 were associated with differential gaze duration for happy (but not disgust faces. Importantly, the allelic groups associated with a greater striatal response to happy faces in the fMRI study were associated with longer gaze duration at happy faces. Conclusions These results suggest that CNR1 variations modulate the striatal function that underlies the perception of signals of social reward, such as happy faces. This suggests that CNR1 is a key element in the molecular architecture of perception of certain basic emotions. This may have implications for understanding neurodevelopmental conditions marked by atypical eye contact and facial emotion processing

  15. Identification of adiponectin receptor agonist utilizing a fluorescence polarization based high throughput assay.

    Science.gov (United States)

    Sun, Yiyi; Zang, Zhihe; Zhong, Ling; Wu, Min; Su, Qing; Gao, Xiurong; Zan, Wang; Lin, Dong; Zhao, Yan; Zhang, Zhonglin

    2013-01-01

    Adiponectin, the adipose-derived hormone, plays an important role in the suppression of metabolic disorders that can result in type 2 diabetes, obesity, and atherosclerosis. It has been shown that up-regulation of adiponectin or adiponectin receptor has a number of therapeutic benefits. Given that it is hard to convert the full size adiponectin protein into a viable drug, adiponectin receptor agonists could be designed or identified using high-throughput screening. Here, we report on the development of a two-step screening process to identify adiponectin agonists. First step, we developed a high throughput screening assay based on fluorescence polarization to identify adiponectin ligands. The fluorescence polarization assay reported here could be adapted to screening against larger small molecular compound libraries. A natural product library containing 10,000 compounds was screened and 9 hits were selected for validation. These compounds have been taken for the second-step in vitro tests to confirm their agonistic activity. The most active adiponectin receptor 1 agonists are matairesinol, arctiin, (-)-arctigenin and gramine. The most active adiponectin receptor 2 agonists are parthenolide, taxifoliol, deoxyschizandrin, and syringin. These compounds may be useful drug candidates for hypoadiponectin related diseases. PMID:23691032

  16. Identification of adiponectin receptor agonist utilizing a fluorescence polarization based high throughput assay.

    Directory of Open Access Journals (Sweden)

    Yiyi Sun

    Full Text Available Adiponectin, the adipose-derived hormone, plays an important role in the suppression of metabolic disorders that can result in type 2 diabetes, obesity, and atherosclerosis. It has been shown that up-regulation of adiponectin or adiponectin receptor has a number of therapeutic benefits. Given that it is hard to convert the full size adiponectin protein into a viable drug, adiponectin receptor agonists could be designed or identified using high-throughput screening. Here, we report on the development of a two-step screening process to identify adiponectin agonists. First step, we developed a high throughput screening assay based on fluorescence polarization to identify adiponectin ligands. The fluorescence polarization assay reported here could be adapted to screening against larger small molecular compound libraries. A natural product library containing 10,000 compounds was screened and 9 hits were selected for validation. These compounds have been taken for the second-step in vitro tests to confirm their agonistic activity. The most active adiponectin receptor 1 agonists are matairesinol, arctiin, (--arctigenin and gramine. The most active adiponectin receptor 2 agonists are parthenolide, taxifoliol, deoxyschizandrin, and syringin. These compounds may be useful drug candidates for hypoadiponectin related diseases.

  17. Activation of CB1 and CB2 receptors attenuates the induction and maintenance of inflammatory pain in the rat.

    Science.gov (United States)

    Elmes, Steven J R; Winyard, Lisa A; Medhurst, Stephen J; Clayton, Nick M; Wilson, Alex W; Kendall, David A; Chapman, Victoria

    2005-12-01

    The aim of the present study was to investigate the effects of cannabinoid agonists on established inflammatory hyperalgesia. We have compared the effects of pre-administration versus post-administration of a potent non-selective cannabinoid agonist HU210 and a selective CB2 receptor agonist JWH-133 on hindpaw weight bearing and paw oedema in the carrageenan model of inflammatory hyperalgesia. For comparative purposes we also determined the effects of the mu-opioid receptor agonist morphine and the COX2 inhibitor rofecoxib in this model. At 3 h following intraplantar injection of carrageenan (2%, 100 microl) there was a significant (P pain responses.

  18. Kaempferol is an estrogen-related receptor alpha and gamma inverse agonist.

    Science.gov (United States)

    Wang, Junjian; Fang, Fang; Huang, Zhiyan; Wang, Yanfei; Wong, Chiwai

    2009-02-18

    Kaempferol is a dietary flavonoid that is thought to function as a selective estrogen receptor modulator. In this study, we established that kaempferol also functions as an inverse agonist for estrogen-related receptors alpha and gamma (ERRalpha and ERRgamma). We demonstrated that kaempferol binds to ERRalpha and ERRgamma and blocks their interaction with coactivator peroxisome proliferator-activated receptor gamma coactivator-1alpha (PGC-1alpha). Kaempferol also suppressed the expressions of ERR-target genes pyruvate dehydrogenase kinase 2 and 4 (PDK2 and PDK4). This evidence suggests that kaempferol may exert some of its biological effect through both estrogen receptors and estrogen-related receptors. PMID:19171140

  19. Preparation of iodine-123 labeled AM251: a potential SPECT radioligand for the brain cannabinoid CB1 receptor

    Energy Technology Data Exchange (ETDEWEB)

    Lan, Ruoxi; Makriyannis, Alexandros [Connecticut Univ., Molecular and Cell Biology Dept., Storrs, CT (United States); Gatley, S.J. [Brookhaven National Lab., Medical Dept., Upton, NY (United States)

    1996-10-01

    We report the synthesis and labeling with iodine-123 of N-(piperidin-1-yl)-5-(4-iodophenyl)-1-(2, 4-dichlorophenyl)-4-methyl-1H-pyrazole-3-carboxamide (AM251). This compound is an analog of the recently described cannabinoid receptor antagonist, SR141716A, in which a 4-chlorophenyl group is replaced by 4-iodophenyl. Labeling in good yield (62%) and radiochemical purity (> 95%), and high specific activity (> 2500 Ci/mmol) was achieved by an iododestannylation reaction using the tributyltin precursor, no carrier added I-123 iodide, and chloramine-T. (author).

  20. Preparation of iodine-123 labeled AM251: a potential SPECT radioligand for the brain cannabinoid CB1 receptor

    International Nuclear Information System (INIS)

    We report the synthesis and labeling with iodine-123 of N-(piperidin-1-yl)-5-(4-iodophenyl)-1-(2, 4-dichlorophenyl)-4-methyl-1H-pyrazole-3-carboxamide (AM251). This compound is an analog of the recently described cannabinoid receptor antagonist, SR141716A, in which a 4-chlorophenyl group is replaced by 4-iodophenyl. Labeling in good yield (62%) and radiochemical purity (> 95%), and high specific activity (> 2500 Ci/mmol) was achieved by an iododestannylation reaction using the tributyltin precursor, no carrier added I-123 iodide, and chloramine-T. (author)

  1. Bombesin receptor subtype-3 agonists stimulate the growth of lung cancer cells and increase EGF receptor tyrosine phosphorylation

    OpenAIRE

    Moody, Terry W.; Sancho, Veronica; Florio, Alessia di; Nuche-Berenguer, Bernardo; Mantey, Samuel; Jensen, Robert T.

    2011-01-01

    The effects of bombesin receptor subtype-3 (BRS-3) agonists were investigated on lung cancer cells. The BRS-3 agonist (DTyr6, βAla11, Phe13, Nle14)bombesin6-14 (BA1), but not gastrin releasing peptide (GRP) or neuromedin B (NMB) increased significantly the clonal growth of NCI-H1299 cells stably transfected with BRS-3 (NCI-H1299-BRS-3). Also, BA1 addition to NCI-H727 or NCI-H1299-BRS-3 cells caused Tyr1068 phosphorylation of the epidermal growth factor receptor (EGFR). Similarly, (DTyr6, R-Ap...

  2. Enhanced self-administration of the CB1 receptor agonist WIN55,212-2 in olfactory bulbectomized rats: evaluation of possible serotonergic and dopaminergic underlying mechanisms

    Directory of Open Access Journals (Sweden)

    Petra eAmchova

    2014-03-01

    Full Text Available Depression has been associated with drug consumption, including heavy or problematic cannabis use. According to an animal model of depression and substance use disorder comorbidity, we combined the olfactory bulbectomy model of depression with intravenous drug self-administration procedure to verify whether depressive-like rats displayed higher voluntary intake of the CB1 receptor agonist WIN55,212-2 (WIN, 12.5 µg/kg/infusion. To this aim, olfactory-bulbectomized (OBX and sham-operated (SHAM Lister Hooded rats were allowed to self-administer WIN by lever-pressing under a continuous (FR-1 schedule of reinforcement in 2h daily sessions. Data showed that both OBX and SHAM rats developed stable WIN intake; yet, responses in OBX were constantly higher than in SHAM rats soon after the first week of training. In addition, OBX rats took significantly longer to extinguish the drug-seeking behaviour after vehicle substitution. Acute pre-treatment with serotonin 5HT1B receptor agonist, CGS-12066B (2.5-10 mg/kg, did not significantly modify WIN intake in OBX and SHAM Lister Hooded rats. Furthermore, acute pre-treatment with CGS-12066B (10 and 15 mg/kg did not alter responses in parallel groups of OBX and SHAM Sprague Dawley rats self-administering methamphetamine under higher (FR-2 reinforcement schedule with nose-poking as operandum. Finally, dopamine levels in the nucleus accumbens of OBX rats did not increase in response to a WIN challenge, as in SHAM rats, indicating a dopaminergic dysfunction in bulbectomized rats. Altogether, our findings suggest that a depressive state may alter cannabinoid CB1 receptor agonist-induced brain reward function and that a dopaminergic rather than a 5-HT1B mechanism is likely to underlie enhanced WIN self-administration in OBX rats.

  3. CB1 cannabinoid receptor in SF1-expressing neurons of the ventromedial hypothalamus determines metabolic responses to diet and leptin.

    Science.gov (United States)

    Cardinal, Pierre; André, Caroline; Quarta, Carmelo; Bellocchio, Luigi; Clark, Samantha; Elie, Melissa; Leste-Lasserre, Thierry; Maitre, Marlene; Gonzales, Delphine; Cannich, Astrid; Pagotto, Uberto; Marsicano, Giovanni; Cota, Daniela

    2014-10-01

    Metabolic flexibility allows rapid adaptation to dietary change, however, little is known about the CNS mechanisms regulating this process. Neurons in the hypothalamic ventromedial nucleus (VMN) participate in energy balance and are the target of the metabolically relevant hormone leptin. Cannabinoid type-1 (CB1) receptors are expressed in VMN neurons, but the specific contribution of endocannabinoid signaling in this neuronal population to energy balance regulation is unknown. Here we demonstrate that VMN CB1 receptors regulate metabolic flexibility and actions of leptin. In chow-fed mice, conditional deletion of CB1 in VMN neurons (expressing the steroidogenic factor 1, SF1) decreases adiposity by increasing sympathetic activity and lipolysis, and facilitates metabolic effects of leptin. Conversely, under high-fat diet, lack of CB1 in VMN neurons produces leptin resistance, blunts peripheral use of lipid substrates and increases adiposity. Thus, CB1 receptors in VMN neurons provide a molecular switch adapting the organism to dietary change.

  4. Identification of human dopamine D1-like receptor agonist using a cell-based functional assay

    Institute of Scientific and Technical Information of China (English)

    Nan JIANG; Ke-qing OU-YANG; Shao-xi CAI; Ying-he HU; Zhi-liang XU

    2005-01-01

    Aim: To establish a cell-based assay to screen human dopamine D1 and D5 receptor agonists against compounds from a natural product compound library.Methods: Synthetic responsive elements 6×cAMP response elements (CRE) and a mini promoter containing a TATA box were inserted into the pGL3 basic vector to generate the reporter gene construct pCRE/TA/Luci. CHO cells were co-transfected with the reporter gene construct and human D1 or D5 receptor cDNA in mammalian expression vectors. Stable cell lines were established for agonist screening. A natural product compound library from over 300 herbs has been established. The extracts from these herbs were used for human D1 and D5 receptor agonist screenings. Results: A number of extracts were identified that activated both D1 and D5 receptors. One of the herb extracts, SBG492, demonstrated distinct pharmacological characteristics with human D1 and D5 receptors.The EC50 values of SBG492 were 342.7 μg/mL for the D1 receptor and 31.7 μg/mL for the D5 receptor. Conclusion: We have established a cell-based assay for high-throughput drug screening to identify D 1-like receptor agonists from natural products. Several extracts that can active D1-like receptors were discovered.These compounds could be useful tools for studies on the functions of these receptors in the brain and could potentially be developed into therapeutic drugs for the treatment of central nervous system diseases.

  5. Cannabinoid receptor CB1 mediates baseline and activity-induced survival of new neurons in adult hippocampal neurogenesis

    Directory of Open Access Journals (Sweden)

    Müller Anke

    2010-06-01

    Full Text Available Abstract Background Adult neurogenesis is a particular example of brain plasticity that is partially modulated by the endocannabinoid system. Whereas the impact of synthetic cannabinoids on the neuronal progenitor cells has been described, there has been lack of information about the action of plant-derived extracts on neurogenesis. Therefore we here focused on the effects of Δ9-tetrahydrocannabinol (THC and Cannabidiol (CBD fed to female C57Bl/6 and Nestin-GFP-reporter mice on proliferation and maturation of neuronal progenitor cells and spatial learning performance. In addition we used cannabinoid receptor 1 (CB1 deficient mice and treatment with CB1 antagonist AM251 in Nestin-GFP-reporter mice to investigate the role of the CB1 receptor in adult neurogenesis in detail. Results THC and CBD differed in their effects on spatial learning and adult neurogenesis. CBD did not impair learning but increased adult neurogenesis, whereas THC reduced learning without affecting adult neurogenesis. We found the neurogenic effect of CBD to be dependent on the CB1 receptor, which is expressed over the whole dentate gyrus. Similarly, the neurogenic effect of environmental enrichment and voluntary wheel running depends on the presence of the CB1 receptor. We found that in the absence of CB1 receptors, cell proliferation was increased and neuronal differentiation reduced, which could be related to CB1 receptor mediated signaling in Doublecortin (DCX-expressing intermediate progenitor cells. Conclusion CB1 affected the stages of adult neurogenesis that involve intermediate highly proliferative progenitor cells and the survival and maturation of new neurons. The pro-neurogenic effects of CBD might explain some of the positive therapeutic features of CBD-based compounds.

  6. Candidate PET radioligands for cannabinoid CB{sub 1} receptors: [{sup 18}F]AM5144 and related pyrazole compounds

    Energy Technology Data Exchange (ETDEWEB)

    Li Zizhong [Center for Translational Neuroimaging, Brookhaven National Laboratory, Upton, NY 11973 (United States); Gifford, Andrew [Center for Translational Neuroimaging, Brookhaven National Laboratory, Upton, NY 11973 (United States); Liu Qian [Center for Drug Discovery, Northeastern University, Boston, MA 02115 (United States); Thotapally, Rajesh [Center for Drug Discovery, Northeastern University, Boston, MA 02115 (United States); Ding Yushin [Center for Translational Neuroimaging, Brookhaven National Laboratory, Upton, NY 11973 (United States); Makriyannis, Alexandros [Center for Drug Discovery, Northeastern University, Boston, MA 02115 (United States); Gatley, S. John [Center for Translational Neuroimaging, Brookhaven National Laboratory, Upton, NY 11973 (United States) and Center for Drug Discovery, Northeastern University, Boston, MA 02115 (United States)]. E-mail: s.gatley@neu.edu

    2005-05-01

    Introduction: The mammalian brain contains abundant G protein-coupled cannabinoid CB{sub 1} receptors that respond to {delta}{sup 9}-tetrahydrocannabinol, the active ingredient of cannabis. The availability of a positron emission tomography (PET) radioligand would facilitate studies of the addictive and medicinal properties of compounds that bind to this receptor. Among the known classes of ligands for CB{sub 1} receptors, the pyrazoles are attractive targets for radiopharmaceutical development because they are antagonists and are generally less lipophilic than the other classes. Methods: A convenient high-yield synthesis of N-(4-[{sup 18}F]fluorophenyl)-5-(4-bromophenyl)-1-(2,4-dichlorophenyl)- 1H-pyrazole-3-carboxamide (AM5144) was devised by coupling the appropriate pyrazole-3-carboxyl chloride compound with 4-[{sup 18}F]fluoroaniline. The labeled precursor was synthesized from 1-[{sup 18}F]fluoro-4-nitrobenzene in 60% radiochemical yield for 10 min using an improved procedure involving sodium borohydride reduction with cobalt chloride catalysis. The product was purified by HPLC to give a specific activity >400 mCi/{mu}mol and a radiochemical purity >95%, and a PET study was conducted in a baboon. Results: Although the regional uptake of AM5144 in baboon brain was consistent with binding to cannabinoid CB{sub 1} receptors, absolute uptake at <0.003% injected radioactivity per cubic centimeter was lower than the previously reported uptake of the radioiodinated pyrazole AM281. Conclusions: The relatively poor brain uptake of AM5144 and other pyrazole CB{sub 1} receptor ligands is not surprising because of their high lipophilicity as compared with most brain PET radiotracers. However, for nine pyrazole compounds for which rodent data are available, brain uptake and calculated logP values are not correlated. Thus, high logP values should not preclude evaluation of radiotracers for targets such as the CB{sub 1} receptor that may require very lipophilic ligands.

  7. Pharmacological blockade of either cannabinoid CB1 or CB2 receptors prevents both cocaine-induced conditioned locomotion and cocaine-induced reduction of cell proliferation in the hippocampus of adult male rat

    OpenAIRE

    Blanco-Calvo, Eduardo; Rivera, Patricia; Arrabal, Sergio; Vargas, Antonio; Pavón, Francisco Javier; Serrano, Antonia; Castilla-Ortega, Estela; Galeano, Pablo; Rubio, Leticia; Suárez, Juan; Rodriguez de Fonseca, Fernando

    2014-01-01

    Addiction to major drugs of abuse, such as cocaine, has recently been linked to alterations in adult neurogenesis in the hippocampus. The endogenous cannabinoid system modulates this proliferative response as demonstrated by the finding that pharmacological activation/blockade of cannabinoid CB1 and CB2 receptors not only modulates neurogenesis but also modulates cell death in the brain. In the present study, we evaluated whether the endogenous cannabinoid system affects cocaine-induced alter...

  8. Pharmacological blockade of either, cannabinoid CB1 or CB2 receptors, prevents both cocaine-induced conditioned locomotion and cocaine-induced reduction of cell proliferation in the hippocampus of adult male rats.

    OpenAIRE

    EDUARDO eBLANCO-CALVO; PATRICIA eRIVERA; SERGIO eARRABAL; ANTONIO eVARGAS; FRANCISCO JAVIER ePAVON; ANTONIA eSERRANO; PABLO eGALEANO; LETICIA eRUBIO; JUAN eSUAREZ; FERNANDO eRODRIGUEZ DE FONSECA

    2014-01-01

    Addiction to major drugs of abuse such as cocaine has been recently linked to alterations on adult neurogenesis in the hippocampus. The endogenous cannabinoid system modulated this proliferative response since pharmacological activation/blockade of cannabinoid CB1 and CB2 receptors by modulating not only neurogenesis but also cell death in the brain. In the present study, we evaluated whether the endogenous cannabinoid system affects cocaine-induced alterations in cell proliferation . To this...

  9. A cation-π interaction at a phenylalanine residue in the glycine receptor binding site is conserved for different agonists

    DEFF Research Database (Denmark)

    Pless, Stephan Alexander; Hanek, Ariele P; Price, Kerry L;

    2011-01-01

    Cation-π interactions have been demonstrated to play a major role in agonist-binding in Cys-loop receptors. However, neither the aromatic amino acid contributing to this interaction nor its location is conserved among Cys-loop receptors. Likewise, it is not clear how many different agonists of a ...

  10. Structural complexes of the agonist, inverse agonist and antagonist bound C5a receptor: insights into pharmacology and signaling.

    Science.gov (United States)

    Rana, Soumendra; Sahoo, Amita Rani; Majhi, Bharat Kumar

    2016-04-26

    The C5a receptor (C5aR) is a pharmacologically important G-protein coupled receptor (GPCR) that interacts with (h)C5a, by recruiting both the "orthosteric" sites (site1 at the N-terminus and site2 at the ECS, extra cellular surface) on C5aR in a two site-binding model. However, the complex pharmacological landscape and the distinguishing chemistry operating either at the "orthosteric" site1 or at the functionally important "orthosteric" site2 of C5aR are still not clear, which greatly limits the understanding of C5aR pharmacology. One of the major bottlenecks is the lack of an experimental structure or a refined model structure of C5aR with appropriately defined active sites. The study attempts to understand the pharmacology at the "orthosteric" site2 of C5aR rationally by generating a highly refined full-blown model structure of C5aR through advanced molecular modeling techniques, and further subjecting it to automated docking and molecular dynamics (MD) studies in the POPC bilayer. The first series of structural complexes of C5aR respectively bound to a linear native peptide agonist ((h)C5a-CT), a small molecule inverse agonist (NDT) and a cyclic peptide antagonist (PMX53) are reported, apparently establishing the unique pharmacological landscape of the "orthosteric" site2, which also illustrates an energetically distinct but coherent competitive chemistry ("cation-π" vs. "π-π" interactions) involved in distinguishing the established ligands known for targeting the "orthosteric" site2 of C5aR. Over a total of 1 μs molecular dynamics (MD) simulation in the POPC bilayer, it is evidenced that while the agonist prefers a "cation-π" interaction, the inverse agonist prefers a "cogwheel/L-shaped" interaction in contrast to the "edge-to-face/T-shaped" type π-π interactions demonstrated by the antagonist by engaging the F275(7.28) of the C5aR. In the absence of a NMR or crystallographically guided model structure of C5aR, the computational model complexes not only

  11. Ascorbic acid enables reversible dopamine receptor /sup 3/H-agonist binding

    Energy Technology Data Exchange (ETDEWEB)

    Leff, S.; Sibley, D.R.; Hamblin, M.; Creese, I.

    1981-11-16

    The effects of ascorbic acid on dopaminergic /sup 3/H-agonist receptor binding were studied in membrane homogenates of bovine anterior pituitary and caudate, and rat striatum. In all tissues virtually no stereospecific binding (defined using 1uM (+)butaclamol) of the /sup 3/H-agonists N-propylnorapomorphine (NPA), apomorphine, or dopamine could be demonstrated in the absence of ascorbic acid. Although levels of total /sup 3/H-agonist binding were three to five times greater in the absence than in the presence of 0.1% ascorbic acid, the increased binding was entirely non-stereospecific. Greater amounts of dopamine-inhibitable /sup 3/H-NPA binding could be demonstrated in the absence of 0.1% ascorbic acid, but this measure of ''specific binding'' was demonstrated not to represent dopamine receptor binding since several other catecholamines and catechol were equipotent with dopamine and more potent than the dopamine agonist (+/-)amino-6,7-dihydroxy-1,2,3,4-tetrahydronapthalene (ADTN) in inhibiting this binding. High levels of dopamine-displaceable /sup 3/H-agonist binding were detected in fresh and boiled homogenates of cerebellum, an area of brain which receives no dopaminergic innervation, further demonstrating the non-specific nature of /sup 3/H-agonist binding in the absence of ascorbic acid. These studies emphasize that under typical assay conditions ascorbic acid is required in order to demonstrate reversible and specific /sup 3/H-agonist binding to dopamine receptors.

  12. Molecular basis of cannabinoid CB1 receptor coupling to the G protein heterotrimer Gαiβγ: identification of key CB1 contacts with the C-terminal helix α5 of Gαi.

    Science.gov (United States)

    Shim, Joong-Youn; Ahn, Kwang H; Kendall, Debra A

    2013-11-01

    The cannabinoid (CB1) receptor is a member of the rhodopsin-like G protein-coupled receptor superfamily. The human CB1 receptor, which is among the most expressed receptors in the brain, has been implicated in several disease states, including drug addiction, anxiety, depression, obesity, and chronic pain. Different classes of CB1 agonists evoke signaling pathways through the activation of specific subtypes of G proteins. The molecular basis of CB1 receptor coupling to its cognate G protein is unknown. As a first step toward understanding CB1 receptor-mediated G protein signaling, we have constructed a ternary complex structural model of the CB1 receptor and Gi heterotrimer (CB1-Gi), guided by the x-ray structure of β2-adrenergic receptor (β2AR) in complex with Gs (β2AR-Gs), through 824-ns duration molecular dynamics simulations in a fully hydrated 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine bilayer environment. We identified a group of residues at the juxtamembrane regions of the intracellular loops 2 and 3 (IC2 and IC3) of the CB1 receptor, including Ile-218(3.54), Tyr-224(IC2), Asp-338(6.30), Arg-340(6.32), Leu-341(6.33), and Thr-344(6.36), as potential key contacts with the extreme C-terminal helix α5 of Gαi. Ala mutations of these residues at the receptor-Gi interface resulted in little G protein coupling activity, consistent with the present model of the CB1-Gi complex, which suggests tight interactions between CB1 and the extreme C-terminal helix α5 of Gαi. The model also suggests that unique conformational changes in the extreme C-terminal helix α5 of Gα play a crucial role in the receptor-mediated G protein activation.

  13. Cannabinoids and haemostasis.

    Science.gov (United States)

    Zakrzeska, Agnieszka; Grędziński, Tomasz; Kisiel, Wioleta; Chabielska, Ewa

    2016-01-01

    Elements of the endocannabinoid system (cannabinoid receptors CB1, CB2, CBPT and CBED, endocannabinoids, enzymes involved in the synthesis and metabolism of endocannabinoids) are located on the structures involved in the process of hemostasis. An increasing level of endocannabinoids was also observed in some pathological conditions, which may occur in disorders of hemostasis. At the same time, disconcertingly, there is an increased number of reports about incidents of cardiovascular events in smokers of marijuana. Experimental and clinical studies demonstrated multidirectional, often contradictory, effects of cannabinoids on hemostasis, including effects of the compounds on platelets, vascular endothelium, fibrinolysis and plasma coagulation systems. The mechanisms of action of cannabinoids on homeostasis depend on the cannabinoid receptors CB1, CB2, CBPT and CBED, receptors of other systems stimulated by endocannabinoids, as well as metabolites of endocannabinoids and nitrogen oxide. The range of biological functions of endo- and plant cannabinoids, expanded to include the process of hemostasis, may constitute a condition for their recognition as a new factor responsible for thromboembolism in smokers of marijuana, in pathological disorders with increased levels of endocannabinoids and in individuals with polymorphisms of FAAH C385A and A385A. On the other hand, there are compelling reasons for anti‑hemostatic action of cannabinoids. PMID:27383573

  14. Farnesoid X receptor agonists attenuate colonic epithelial secretory function and prevent experimental diarrhoea in vivo.

    OpenAIRE

    FALLON, PADRAIC

    2014-01-01

    OBJECTIVE: Bile acids are important regulators of intestinal physiology, and the nuclear bile acid receptor, farnesoid X receptor (FXR), is emerging as a promising therapeutic target for several intestinal disorders. Here, we investigated a role for FXR in regulating intestinal fluid and electrolyte transport and the potential for FXR agonists in treating diarrhoeal diseases. DESIGN: Electrogenic ion transport was measured as changes in short-circuit current across voltage-clamped ...

  15. Identification of Adiponectin Receptor Agonist Utilizing a Fluorescence Polarization Based High Throughput Assay

    OpenAIRE

    Yiyi Sun; Zhihe Zang; Ling Zhong; Min Wu; Qing Su; Xiurong Gao; Wang Zan; Dong Lin; Yan Zhao; Zhonglin Zhang

    2013-01-01

    Adiponectin, the adipose-derived hormone, plays an important role in the suppression of metabolic disorders that can result in type 2 diabetes, obesity, and atherosclerosis. It has been shown that up-regulation of adiponectin or adiponectin receptor has a number of therapeutic benefits. Given that it is hard to convert the full size adiponectin protein into a viable drug, adiponectin receptor agonists could be designed or identified using high-throughput screening. Here, we report on the deve...

  16. A new agonist of the erythropoietin receptor, Epobis, induces neurite outgrowth and promotes neuronal survival

    DEFF Research Database (Denmark)

    Pankratova, Stanislava; Gu, Bing; Kiryushko, Darya;

    2012-01-01

    Apart from its hematopoietic activity, erythropoietin (EPO) is also known as a tissue-protective cytokine. In the brain, EPO and its receptor are up-regulated in response to insult and exert pro-survival effects. EPO binds to its receptor (EPOR) via high- and low-affinity binding sites (Sites 1....... Thus, we identified a new functional agonist of EPOR with the potential to promote neuroregeneration and neuroprotection....

  17. PEROXISOME PROLIFERATOR-ACTIVATED RECEPTOR (PPAR) AGONISTS AS PROMISING NEW MEDICATIONS FOR DRUG ADDICTION: PRECLINICAL EVIDENCE

    OpenAIRE

    Foll, Bernard Le; Ciano, Patricia Di; Panlilio, Leigh V; Goldberg, Steven R.; Ciccocioppo, Roberto

    2013-01-01

    This review examines the growing literature on the role of peroxisome proliferator-activated receptors (PPARs) in addiction. There are two subtypes of PPAR receptors that have been studied in addiction: PPAR-α and PPAR-γ. The role of each PPAR subtype in common models of addictive behavior, mainly pre-clinical models, is summarized. In particular, studies are reviewed that investigated the effects of PPAR-α agonists on relapse, sensitization, conditioned place preference, withdrawal and drug ...

  18. Lixisenatide, a novel GLP-1 receptor agonist for the treatment of type 2 diabetes mellitus

    DEFF Research Database (Denmark)

    Christensen, Mikkel; Knop, Filip K; Holst, Jens Juul;

    2009-01-01

    Lixisenatide, under development by sanofi-aventis, is a novel human glucagon-like peptide-1 receptor (GLP-1R) agonist for the treatment of type 2 diabetes mellitus (T2DM; non-insulin dependent diabetes). The structure of lixisenatide, based on exendin-4(1-39) modified C-terminally with six Lys...

  19. Identification of the first surrogate agonists for the G protein-coupled receptor GPR132

    DEFF Research Database (Denmark)

    Shehata, Mohamed A.; Christensen, Hanna Belcik; Isberg, Vignir;

    2015-01-01

    -arrestin recruitment assay, and thereby identified the first disclosed surrogate GPR132 agonist 1 with a potency of 3.4 μM. This constitutes the first available pharmacological tool for the in vitro characterization of the orphan receptor GPR132. The testing of 32 analogs furthermore identified a number of compounds...

  20. Interaction of a non-peptide agonist with angiotensin II AT1 receptor mutants

    DEFF Research Database (Denmark)

    Costa-Neto, Claudio M; Miyakawa, Ayumi A; Pesquero, João B;

    2002-01-01

    To identify residues of the rat AT1A angiotensin II receptor involved with signal transduction and binding of the non-peptide agonist L-162,313 (5,7-dimethyl-2-ethyl-3-[[4-[2(n-butyloxycarbonylsulfonamido)-5-isobutyl-3-thienyl]phenyl]methyl]imidazol[4,5,6]-pyridine) we have performed ligand bindi...

  1. Glucagon-like peptide-1 receptor agonist treatment reduces beta cell mass in normoglycaemic mice

    NARCIS (Netherlands)

    Ellenbroek, J.H.; Tons, H.A.; Westerouen van Meeteren, M.J.; de Graaf, N.; Hanegraaf, M.A.; Rabelink, T.J.; Carlotti, F.; de Koning, E.J.

    2013-01-01

    AIMS/HYPOTHESIS: Incretin-based therapies improve glycaemic control in patients with type 2 diabetes. In animal models of diabetes, glucagon-like peptide-1 receptor agonists (GLP-1RAs) increase beta cell mass. GLP-1RAs are also evaluated in non-diabetic individuals with obesity and cardiovascular di

  2. Small-molecule agonists for the glucagon-like peptide 1 receptor

    DEFF Research Database (Denmark)

    Knudsen, Lotte Bjerre; Kiel, Dan; Teng, Min;

    2007-01-01

    The peptide hormone glucagon-like peptide (GLP)-1 has important actions resulting in glucose lowering along with weight loss in patients with type 2 diabetes. As a peptide hormone, GLP-1 has to be administered by injection. Only a few small-molecule agonists to peptide hormone receptors have been...

  3. Treatment potential of the GLP-1 receptor agonists in type 2 diabetes mellitus

    DEFF Research Database (Denmark)

    Østergaard, L; Frandsen, Christian S; Madsbad, S

    2016-01-01

    Over the last decade, the discovery of glucagon-like peptide 1 receptor agonists (GLP-1 RAs) has increased the treatment options for patients with type 2 diabetes mellitus (T2DM). GLP-1 RAs mimic the effects of native GLP-1, which increases insulin secretion, inhibits glucagon secretion, increases...

  4. [Cardiovascular effects of GLP-1 receptor agonist treatment: focus on liraglutide].

    Science.gov (United States)

    Haluzík, Martin; Trachta, Pavel; Mráz, Miloš

    2015-01-01

    Cardiovascular risk reduction is the major aim of type 2 diabetes mellitus treatment. The effects of various antidiabetics on the cardiovascular complications are currently under careful scrutiny. Incretin-based therapy that utilizes the effects of glucagon-like peptide 1 (GLP-1) or stimulation of its receptor by GLP-1 receptor agonists represents one of the most promising approaches from the potential cardiovascular risk reduction point of view. Experimental studies have shown that the GLP-1 and GLP-1 agonists treatment improves endothelial function, decrease blood pressure and protects myocardium during experimentally-induced ischemia. Clinical studies with GLP-1 receptor agonists consistently show that, in addition to good antidiabetic efficacy, its long-term administration decreases blood pressure, body weight and improves circulating lipid levels while slightly increasing heart rate. In this paper, we focus on the cardiovascular effects of GLP-1 receptor agonist liraglutide. Preliminary analyses of cardiovascular complications in phase III trials with liraglutide indicate its good cardiovascular safety. A possibility of cardioprotective effects of liraglutide remains still open and is currently studied within a prospective cardiovascular trial LEADER.

  5. Biostructural and pharmacological studies of bicyclic analogues of the 3-isoxazolol glutamate receptor agonist ibotenic acid

    DEFF Research Database (Denmark)

    Frydenvang, Karla Andrea; Pickering, Darryl S; Greenwood, Jeremy R;

    2010-01-01

    We describe an improved synthesis and detailed pharmacological characterization of the conformationally restricted analogue of the naturally occurring nonselective glutamate receptor agonist ibotenic acid (RS)-3-hydroxy-4,5,6,7-tetrahydroisoxazolo[5,4-c]pyridine-7-carboxylic acid (7-HPCA, 5) at A...

  6. The preclinical properties of a novel group II metabotropic glutamate receptor agonist LY379268

    NARCIS (Netherlands)

    Imre, Gabor

    2007-01-01

    Activation of group II metabotropic glutamate (mGlu2/3) receptors reduces excessive glutamate release that is often associated with neurodegenerative and psychiatric disorders. This finding encouraged the search for potent and selective agonists as potential therapeutic agents. The search led to the

  7. Therapeutic efficacy of the adenosine A1 receptor agonist N6-cyclopentyladenosine (CPA) against organophosphate intoxication

    NARCIS (Netherlands)

    Bueters, T.J.H.; Groen, B.; Danhof, M.; IJzerman, A.P.; Helden, H.P.M. van

    2002-01-01

    The objective of the present study was to investigate whether reduction of central acetylcholine (ACh) accumulation by adenosine receptor agonists could serve as a generic treatment against organophosphate (OP) poisoning. The OPs studied were tabun (O-ethyl-N-dimethylphosphoramidocyanidate), sarin (

  8. Non-Acidic Free Fatty Acid Receptor 4 Agonists with Antidiabetic Activity

    DEFF Research Database (Denmark)

    Azevedo, Carlos M G; Watterson, Kenneth R; Wargent, Ed T;

    2016-01-01

    The free fatty acid receptor 4 (FFA4 or GPR120) has appeared as an interesting potential target for the treatment of metabolic disorders. At present, most FFA4 ligands are carboxylic acids that are assumed to mimic the endogenous long-chain fatty acid agonists. Here, we report preliminary structure...

  9. Novel non-indolic melatonin receptor agonists differentially entrain endogenous melatonin rhythm and increase its amplitude

    NARCIS (Netherlands)

    Drijfhout, W.J; de Vries, J.B; Homan, E.J; Brons, H.F; Copinga, S; Gruppen, G; Beresford, I.J M; Hagan, R.M; Grol, Cor; Westerink, B.H.C.

    1999-01-01

    In this study we have examined the ability of melatonin and four synthetic melatonin receptor agonists to entrain endogenous melatonin secretion in rats, free running in constant darkness. The circadian melatonin profile was measured by trans-pineal microdialysis, which not only reveals the time of

  10. Neuritogenic and neuroprotective properties of peptide agonists of the fibroblast growth factor receptor

    DEFF Research Database (Denmark)

    Li, Shizhong; Bock, Elisabeth Marianne; Berezin, Vladimir

    2010-01-01

    Fibroblast growth factor receptors (FGFRs) interact with their cognate ligands, FGFs, and with a number of cell adhesion molecules (CAMs), such as the neural cell adhesion molecule (NCAM), mediating a wide range of events during the development and maintenance of the nervous system. Determination...... developed functional peptide agonists of FGFR with possible therapeutic potential....

  11. Sigma-1 receptor agonists directly inhibit Nav1.2/1.4 channels.

    Directory of Open Access Journals (Sweden)

    Xiao-Fei Gao

    Full Text Available (+-SKF 10047 (N-allyl-normetazocine is a prototypic and specific sigma-1 receptor agonist that has been used extensively to study the function of sigma-1 receptors. (+-SKF 10047 inhibits K(+, Na(+ and Ca2+ channels via sigma-1 receptor activation. We found that (+-SKF 10047 inhibited Na(V1.2 and Na(V1.4 channels independently of sigma-1 receptor activation. (+-SKF 10047 equally inhibited Na(V1.2/1.4 channel currents in HEK293T cells with abundant sigma-1 receptor expression and in COS-7 cells, which barely express sigma-1 receptors. The sigma-1 receptor antagonists BD 1063,BD 1047 and NE-100 did not block the inhibitory effects of (+-SKF-10047. Blocking of the PKA, PKC and G-protein pathways did not affect (+-SKF 10047 inhibition of Na(V1.2 channel currents. The sigma-1 receptor agonists Dextromethorphan (DM and 1,3-di-o-tolyl-guanidine (DTG also inhibited Na(V1.2 currents through a sigma-1 receptor-independent pathway. The (+-SKF 10047 inhibition of Na(V1.2 currents was use- and frequency-dependent. Point mutations demonstrated the importance of Phe(1764 and Tyr(1771 in the IV-segment 6 domain of the Na(V1.2 channel and Phe(1579 in the Na(V1.4 channel for (+-SKF 10047 inhibition. In conclusion, our results suggest that sigma-1 receptor agonists directly inhibit Na(V1.2/1.4 channels and that these interactions should be given special attention for future sigma-1 receptor function studies.

  12. Cannabinoid CB2 receptor activation inhibits mechanically evoked responses of wide dynamic range dorsal horn neurons in naïve rats and in rat models of inflammatory and neuropathic pain.

    Science.gov (United States)

    Elmes, Steven J R; Jhaveri, Maulik D; Smart, Darren; Kendall, David A; Chapman, Victoria

    2004-11-01

    Peripheral cannabinoid 2 receptors (CB2 receptors) modulate immune responses and attenuate nociceptive behaviour in models of acute and persistent pain. The aim of the present study was to investigate whether peripheral CB2 receptors modulate spinal processing of innocuous and noxious responses and to determine whether there are altered roles of CB2 receptors in models of persistent pain. Effects of local administration of the CB2 receptor agonist JWH-133 (5 and 15 microg/50 microL) on mechanically evoked responses of spinal wide dynamic range (WDR) neurons in noninflamed rats, rats with carrageenan-induced hindpaw inflammation, sham operated rats and spinal nerve-ligated (SNL) rats were determined in anaesthetized rats in vivo. Mechanical stimulation (von Frey filaments, 6-80 g) of the peripheral receptive field evoked firing of WDR neurons. Mechanically evoked responses of WDR neurons were similar in noninflamed, carrageenan-inflamed, sham-operated and SNL rats. Intraplantar injection of JWH-133 (15 microg), but not vehicle, significantly (P pain.

  13. Cannabinoids in the management of difficult to treat pain.

    Science.gov (United States)

    Russo, Ethan B

    2008-02-01

    This article reviews recent research on cannabinoid analgesia via the endocannabinoid system and non-receptor mechanisms, as well as randomized clinical trials employing cannabinoids in pain treatment. Tetrahydrocannabinol (THC, Marinol((R))) and nabilone (Cesamet((R))) are currently approved in the United States and other countries, but not for pain indications. Other synthetic cannabinoids, such as ajulemic acid, are in development. Crude herbal cannabis remains illegal in most jurisdictions but is also under investigation. Sativex((R)), a cannabis derived oromucosal spray containing equal proportions of THC (partial CB(1) receptor agonist ) and cannabidiol (CBD, a non-euphoriant, anti-inflammatory analgesic with CB(1) receptor antagonist and endocannabinoid modulating effects) was approved in Canada in 2005 for treatment of central neuropathic pain in multiple sclerosis, and in 2007 for intractable cancer pain. Numerous randomized clinical trials have demonstrated safety and efficacy for Sativex in central and peripheral neuropathic pain, rheumatoid arthritis and cancer pain. An Investigational New Drug application to conduct advanced clinical trials for cancer pain was approved by the US FDA in January 2006. Cannabinoid analgesics have generally been well tolerated in clinical trials with acceptable adverse event profiles. Their adjunctive addition to the pharmacological armamentarium for treatment of pain shows great promise. PMID:18728714

  14. Dimerization of the D1 dopamine receptors is related with agonist and inverse agonist-induced receptor internalization

    Institute of Scientific and Technical Information of China (English)

    Yi-minTAO; Xue-junXU; Min-huaHONG; JieCHEN; Zhi-qiangCHI; Jing-genLIU

    2004-01-01

    AIM: To examine the relationship between D1 dopamine receptor dimer formation and ligand-induced receptor internalization. METHODS: FLAG-tagged D 1 dopamine receptor was transiently expressed in Sf9 cells. The cells were treated with SKF38393 or (+)butaclamol 1 μmol/L for different periods timeor at different doses for 30 min respectively. Western blot assaywas performed to assess dimer formation and flow evtomv.tv.r

  15. CB1 cannabinoid receptor participates in the vascular hyporeactivity resulting from hemorrhagic shock in rats

    Institute of Scientific and Technical Information of China (English)

    HOU Li-chao; LI Nan; ZHENG Li-na; LU Yan; XIE Ke-liang; WANG Yue-min; JI Gen-lin; XIONG Li-ze

    2009-01-01

    Background Vascular hyporeactivity, which occurs in the terminal stage of hemorrhagic shock, is believed to be critical for treating hemorrhagic shock. The present study was designed to examine whether the CB1 cannabinoid receptor (CB1R) was involved in the development of vascular hyporeactivity in rats suffering from hemorrhagic shock.Methods Sixteen animals were randomly divided into two groups (n=8 in each group): sham-operated (Sham) and hemorrhagic shock (HS) groups. Hemorrhagic shock was induced by bleeding. The mean arterial pressure (MAP) was reduced to and stabilized at (25±5) mmHg for 2 hours. The vascular reactivity was determined by the response of MAP to norepinephrine (NE). In later experiments another twelve animals were used in which the changes of CB1R mRNA and protein in aorta and superior mesenteric artery (SMA) were analyzed by RT-PCR and Western blotting. In addition, we investigated the effects of a CB1R antagonist on the vascular hyporeactivity and survival rates in rats with hemorrhagic shock. Survival rates were analyzed by the Fisher's exact probability test. The MAP response was analyzed by one-way analysis of variance (ANOVA).Results Vascular hyporeactivity developed in all animals suffering from hemorrhagic shock. The expression of CB1R mRNA and protein in aorta and 2-3 branches of the SMA were significantly increased in the HS group after the development of vascular hyporeactivity when compared to those in Sham group. When SR141716A or AM251 was administered, the MAP response to NE was (41.75±4.08) mmHg or (44.78±1.80) mmHg respectively, which was higher than that in saline groups with (4.31±0.36) mmHg (P<0.01). We also showed an increased 4-hour survival rate in the SR141716A or AM251-treated group with 20% or 30%, but with a statistically significant difference present between the AM251-treated and saline groups (P<0.05).Conclusions CB1R is involved in vascular hyporeactivity resulting from hemorrhagic shock in rats, and CB1R

  16. The CB₁ cannabinoid receptor signals striatal neuroprotection via a PI3K/Akt/mTORC1/BDNF pathway.

    Science.gov (United States)

    Blázquez, C; Chiarlone, A; Bellocchio, L; Resel, E; Pruunsild, P; García-Rincón, D; Sendtner, M; Timmusk, T; Lutz, B; Galve-Roperh, I; Guzmán, M

    2015-10-01

    The CB1 cannabinoid receptor, the main molecular target of endocannabinoids and cannabis active components, is the most abundant G protein-coupled receptor in the mammalian brain. In particular, the CB1 receptor is highly expressed in the basal ganglia, mostly on terminals of medium-sized spiny neurons, where it plays a key neuromodulatory function. The CB1 receptor also confers neuroprotection in various experimental models of striatal damage. However, the assessment of the physiological relevance and therapeutic potential of the CB1 receptor in basal ganglia-related diseases is hampered, at least in part, by the lack of knowledge of the precise mechanism of CB1 receptor neuroprotective activity. Here, by using an array of pharmacological, genetic and pharmacogenetic (designer receptor exclusively activated by designer drug) approaches, we show that (1) CB1 receptor engagement protects striatal cells from excitotoxic death via the phosphatidylinositol 3-kinase/Akt/mammalian target of rapamycin complex 1 pathway, which, in turn, (2) induces brain-derived neurotrophic factor (BDNF) expression through the selective activation of BDNF gene promoter IV, an effect that is mediated by multiple transcription factors. To assess the possible functional impact of the CB1/BDNF axis in a neurodegenerative-disease context in vivo, we conducted experiments in the R6/2 mouse, a well-established model of Huntington's disease, in which the CB1 receptor and BDNF are known to be severely downregulated in the dorsolateral striatum. Adeno-associated viral vector-enforced re-expression of the CB1 receptor in the dorsolateral striatum of R6/2 mice allowed the re-expression of BDNF and the concerted rescue of the neuropathological deficits in these animals. Collectively, these findings unravel a molecular link between CB1 receptor activation and BDNF expression, and support the relevance of the CB1/BDNF axis in promoting striatal neuron survival. PMID:25698444

  17. Recent advances in the development of farnesoid X receptor agonists

    OpenAIRE

    Ali, Ahmad H; Carey, Elizabeth J.; Lindor, Keith D

    2015-01-01

    Farnesoid X receptors (FXRs) are nuclear hormone receptors expressed in high amounts in body tissues that participate in bilirubin metabolism including the liver, intestines, and kidneys. Bile acids (BAs) are the natural ligands of the FXRs. FXRs regulate the expression of the gene encoding for cholesterol 7 alpha-hydroxylase, which is the rate-limiting enzyme in BA synthesis. In addition, FXRs play a critical role in carbohydrate and lipid metabolism and regulation of insulin sensitivity. FX...

  18. Arachidonic acid mediates non-capacitative calcium entry evoked by CB1-cannabinoid receptor activation in DDT1 MF-2 smooth muscle cells

    NARCIS (Netherlands)

    Demuth, D.G.; Gkoumassi, Effimia; Droge, M.J.; Dekkers, B.G.J.; Esselink, H.J.; van Ree, Rutger; Parsons, M.E.; Zaagsma, Hans; Molleman, A; Nelemans, Herman

    2005-01-01

    Cannabinoid CB1-receptor stimulation in DDT1 MF-2 smooth muscle cells induces a rise in [Ca2+](i), which is dependent on extracellular Ca2+ and modulated by thapsigargin-sensitive stores, suggesting capacitative Ca2+ entry (CCE), and by MAP kinase. Non-capacitative Ca2+ entry (NCCE) stimulated by ar

  19. Oxygenated metabolites of anandamide and 2-arachidonoylglycerol : conformational analysis and interaction with cannabinoid receptors, membrane transporter, and fatty acid amide hydrolase

    NARCIS (Netherlands)

    Vliegenthart, J.F.G.; Stelt, M. van der; Kuik, J.A. van; Zadelhoff, G. van; Leeflang, B.R.; Veldink, G.A.; Finazzi Agrò, A.; Maccarrone, M.

    2002-01-01

    This study was aimed at finding structural requirements for the interaction of the acyl chain of endocannabinoids with cannabinoid receptors, membrane transporter protein, and fatty acid amide hydrolase (FAAH). To this end, the flexibility of the acyl chain was restricted by introduction of an 1-hyd

  20. 5-HT2 Receptor Regulation of Mitochondrial Genes: Unexpected Pharmacological Effects of Agonists and Antagonists.

    Science.gov (United States)

    Harmon, Jennifer L; Wills, Lauren P; McOmish, Caitlin E; Demireva, Elena Y; Gingrich, Jay A; Beeson, Craig C; Schnellmann, Rick G

    2016-04-01

    In acute organ injuries, mitochondria are often dysfunctional, and recent research has revealed that recovery of mitochondrial and renal functions is accelerated by induction of mitochondrial biogenesis (MB). We previously reported that the nonselective 5-HT2 receptor agonist DOI [1-(4-iodo-2,5-dimethoxyphenyl)propan-2-amine] induced MB in renal proximal tubular cells (RPTCs). The goal of this study was to determine the role of 5-HT2 receptors in the regulation of mitochondrial genes and oxidative metabolism in the kidney. The 5-HT2C receptor agonist CP-809,101 [2-[(3-chlorophenyl)methoxy]-6-(1-piperazinyl)pyrazine] and antagonist SB-242,084 [6-chloro-2,3-dihydro-5-methyl-N-[6-[(2-methyl-3-pyridinyl)oxy]-3-pyridinyl]-1H-indole-1-carboxyamide dihydrochloride] were used to examine the induction of renal mitochondrial genes and oxidative metabolism in RPTCs and in mouse kidneys in the presence and absence of the 5-HT2C receptor. Unexpectedly, both CP-809,101 and SB-242,084 increased RPTC respiration and peroxisome proliferator-activated receptor γ coactivator-1α (PGC-1α) mRNA expression in RPTCs at 1-10 nM. In addition, CP-809,101 and SB-242,084 increased mRNA expression of PGC-1α and the mitochondrial proteins NADH dehydrogenase subunit 1 and NADH dehydrogenase (ubiquinone) β subcomplex 8 in mice. These compounds increased mitochondrial genes in RPTCs in which the 5-HT2C receptor was downregulated with small interfering RNA and in the renal cortex of mice lacking the 5-HT2C receptor. By contrast, the ability of these compounds to increase PGC-1α mRNA and respiration was blocked in RPTCs treated with 5-HT2A receptor small interfering RNA or the 5-HT2A receptor antagonist eplivanserin. In addition, the 5-HT2A receptor agonist NBOH-2C-CN [4-[2-[[(2-hydroxyphenyl)methyl]amino]ethyl]-2,5-dimethoxybenzonitrile] increased RPTC respiration at 1-100 nM. These results suggest that agonism of the 5-HT2A receptor induces MB and that the classic 5-HT2C receptor agonist CP

  1. Involvement of tyrosine residues located in the carboxyl tail of the human beta 2-adrenergic receptor in agonist-induced down-regulation of the receptor.

    OpenAIRE

    Valiquette, M; Bonin, H.; Hnatowich, M; Caron, M G; Lefkowitz, R J; Bouvier, M

    1990-01-01

    Chronic exposure of various cell types to adrenergic agonists leads to a decrease in cell surface beta 2-adrenergic receptor (beta 2AR) number. Sequestration of the receptor away from the cell surface as well as a down-regulation of the total number of cellular receptors are believed to contribute to this agonist-mediated regulation of receptor number. However, the molecular mechanisms underlying these phenomena are not well characterized. Recently, tyrosine residues located in the cytoplasmi...

  2. Localization and function of the cannabinoid CB1 receptor in the anterolateral bed nucleus of the stria terminalis.

    Directory of Open Access Journals (Sweden)

    Nagore Puente

    Full Text Available BACKGROUND: The bed nucleus of the stria terminalis (BNST is involved in behaviors related to natural reward, drug addiction and stress. In spite of the emerging role of the endogenous cannabinoid (eCB system in these behaviors, little is known about the anatomy and function of this system in the anterolateral BNST (alBNST. The aim of this study was to provide a detailed morphological characterization of the localization of the cannabinoid 1 (CB1 receptor a necessary step toward a better understanding of the physiological roles of the eCB system in this region of the brain. METHODOLOGY/PRINCIPAL FINDINGS: We have combined anatomical approaches at the confocal and electron microscopy level to ex-vivo electrophysiological techniques. Here, we report that CB1 is localized on presynaptic membranes of about 55% of immunopositive synaptic terminals for the vesicular glutamate transporter 1 (vGluT1, which contain abundant spherical, clear synaptic vesicles and make asymmetrical synapses with alBNST neurons. About 64% of vGluT1 immunonegative synaptic terminals show CB1 immunolabeling. Furthermore, 30% and 35% of presynaptic boutons localize CB1 in alBNST of conditional mutant mice lacking CB1 mainly from GABAergic neurons (GABA-CB1-KO mice and mainly from cortical glutamatergic neurons (Glu-CB1-KO mice, respectively. Extracellular field recordings and whole cell patch clamp in the alBNST rat brain slice preparation revealed that activation of CB1 strongly inhibits excitatory and inhibitory synaptic transmission. CONCLUSIONS/SIGNIFICANCE: This study supports the anterolateral BNST as a potential neuronal substrate of the effects of cannabinoids on stress-related behaviors.

  3. Antimitogenic effect of bitter taste receptor agonists on airway smooth muscle cells.

    Science.gov (United States)

    Sharma, Pawan; Panebra, Alfredo; Pera, Tonio; Tiegs, Brian C; Hershfeld, Alena; Kenyon, Lawrence C; Deshpande, Deepak A

    2016-02-15

    Airway remodeling is a hallmark feature of asthma and chronic obstructive pulmonary disease. Clinical studies and animal models have demonstrated increased airway smooth muscle (ASM) mass, and ASM thickness is correlated with severity of the disease. Current medications control inflammation and reverse airway obstruction effectively but have limited effect on remodeling. Recently we identified the expression of bitter taste receptors (TAS2R) on ASM cells, and activation with known TAS2R agonists resulted in ASM relaxation and bronchodilation. These studies suggest that TAS2R can be used as new therapeutic targets in the treatment of obstructive lung diseases. To further establish their effectiveness, in this study we aimed to determine the effects of TAS2R agonists on ASM growth and promitogenic signaling. Pretreatment of healthy and asthmatic human ASM cells with TAS2R agonists resulted in a dose-dependent inhibition of ASM proliferation. The antimitogenic effect of TAS2R ligands was not dependent on activation of protein kinase A, protein kinase C, or high/intermediate-conductance calcium-activated K(+) channels. Immunoblot analyses revealed that TAS2R agonists inhibit growth factor-activated protein kinase B phosphorylation without affecting the availability of phosphatidylinositol 3,4,5-trisphosphate, suggesting TAS2R agonists block signaling downstream of phosphatidylinositol 3-kinase. Furthermore, the antimitogenic effect of TAS2R agonists involved inhibition of induced transcription factors (activator protein-1, signal transducer and activator of transcription-3, E2 factor, nuclear factor of activated T cells) and inhibition of expression of multiple cell cycle regulatory genes, suggesting a direct inhibition of cell cycle progression. Collectively, these findings establish the antimitogenic effect of TAS2R agonists and identify a novel class of receptors and signaling pathways that can be targeted to reduce or prevent airway remodeling as well as

  4. Comparative pharmacology of bombesin receptor subtype-3, nonpeptide agonist MK-5046, a universal peptide agonist, and peptide antagonist Bantag-1 for human bombesin receptors.

    Science.gov (United States)

    Moreno, Paola; Mantey, Samuel A; Nuche-Berenguer, Bernardo; Reitman, Marc L; González, Nieves; Coy, David H; Jensen, Robert T

    2013-10-01

    Bombesin-receptor-subtype-3 (BRS-3) is an orphan G-protein-coupled receptor of the bombesin (Bn) family whose natural ligand is unknown and which does not bind any natural Bn-peptide with high affinity. It is present in the central nervous system, peripheral tissues, and tumors; however, its role in normal physiology/pathophysiology is largely unknown because of the lack of selective ligands. Recently, MK-5046 [(2S)-1,1,1-trifluoro-2-[4-(1H-pyrazol-1-yl)phenyl]-3-(4-{[1-(trifluoromethyl)cyclopropyl]methyl}-1H-imidazol-2-yl)propan-2-ol] and Bantag-1 [Boc-Phe-His-4-amino-5-cyclohexyl-2,4,5-trideoxypentonyl-Leu-(3-dimethylamino) benzylamide N-methylammonium trifluoroacetate], a nonpeptide agonist and a peptide antagonist, respectively, for BRS-3 have been described, but there have been limited studies on their pharmacology. We studied MK-5046 and Bantag-1 interactions with human Bn-receptors-human bombesin receptor subtype-3 (hBRS-3), gastrin-releasing peptide receptor (GRP-R), and neuromedin B receptor (NMB-R)-and compared them with the nonselective, peptide-agonist [d-Tyr6,βAla11,Phe13,Nle14]Bn-(6-14) (peptide #1). Receptor activation was detected by activation of phospholipase C (PLC), mitogen-activated protein kinase (MAPK), focal adhesion kinase (FAK), paxillin, and Akt. In hBRS-3 cells, the relative affinities were Bantag-1 (1.3 nM) > peptide #1 (2 nM) > MK-5046 (37-160 nM) > GRP, NMB (>10 μM), and the binding-dose-inhibition curves were broad (>4 logs), with Hill coefficients differing significantly from unity. Curve-fitting demonstrated high-affinity (MK-5046, Ki = 0.08 nM) and low-affinity (MK-5046, Ki = 11-29 nM) binding sites. For PLC activation in hBRS-3 cells, the relative potencies were MK-5046 (0.02 nM) > peptide #1 (6 nM) > GRP, NMB, Bantag-1 (>10 μM), and MK-5046 had a biphasic dose response, whereas peptide #1 was monophasic. Bantag-1 was a specific hBRS-3-antagonist. In hBRS-3 cells, MK-5046 was a full agonist for activation of MAPK, FAK, Akt

  5. Preclinical evaluation and quantification of [{sup 18}F]MK-9470 as a radioligand for PET imaging of the type 1 cannabinoid receptor in rat brain

    Energy Technology Data Exchange (ETDEWEB)

    Casteels, Cindy [K.U. Leuven, University Hospital Leuven, Division of Nuclear Medicine, Leuven (Belgium); K.U. Leuven, MoSAIC, Molecular Small Animal Imaging Center, Leuven (Belgium); University Hospital Gasthuisberg, Division of Nuclear Medicine, Leuven (Belgium); Koole, Michel; Laere, Koen van [K.U. Leuven, University Hospital Leuven, Division of Nuclear Medicine, Leuven (Belgium); K.U. Leuven, MoSAIC, Molecular Small Animal Imaging Center, Leuven (Belgium); Celen, Sofie; Bormans, Guy [K.U. Leuven, MoSAIC, Molecular Small Animal Imaging Center, Leuven (Belgium); K.U. Leuven, Laboratory for Radiopharmacy, Leuven (Belgium)

    2012-09-15

    [{sup 18}F]MK-9470 is an inverse agonist for the type 1 cannabinoid (CB1) receptor allowing its use in PET imaging. We characterized the kinetics of [{sup 18}F]MK-9470 and evaluated its ability to quantify CB1 receptor availability in the rat brain. Dynamic small-animal PET scans with [{sup 18}F]MK-9470 were performed in Wistar rats on a FOCUS-220 system for up to 10 h. Both plasma and perfused brain homogenates were analysed using HPLC to quantify radiometabolites. Displacement and blocking experiments were done using cold MK-9470 and another inverse agonist, SR141716A. The distribution volume (V{sub T}) of [{sup 18}F]MK-9470 was used as a quantitative measure and compared to the use of brain uptake, expressed as SUV, a simplified method of quantification. The percentage of intact [{sup 18}F]MK-9470 in arterial plasma samples was 80 {+-} 23 % at 10 min, 38 {+-} 30 % at 40 min and 13 {+-} 14 % at 210 min. A polar radiometabolite fraction was detected in plasma and brain tissue. The brain radiometabolite concentration was uniform across the whole brain. Displacement and pretreatment studies showed that 56 % of the tracer binding was specific and reversible. V{sub T} values obtained with a one-tissue compartment model plus constrained radiometabolite input had good identifiability ({<=}10 %). Ignoring the radiometabolite contribution using a one-tissue compartment model alone, i.e. without constrained radiometabolite input, overestimated the [{sup 18}F]MK-9470 V{sub T}, but was correlated. A correlation between [{sup 18}F]MK-9470 V{sub T} and SUV in the brain was also found (R {sup 2} = 0.26-0.33; p {<=} 0.03). While the presence of a brain-penetrating radiometabolite fraction complicates the quantification of [{sup 18}F]MK-9470 in the rat brain, its tracer kinetics can be modelled using a one-tissue compartment model with and without constrained radiometabolite input. (orig.)

  6. The use of anchored agonists of phagocytic receptors for cancer immunotherapy: B16-F10 murine melanoma model.

    Directory of Open Access Journals (Sweden)

    Tereza Janotová

    Full Text Available The application of the phagocytic receptor agonists in cancer immunotherapy was studied. Agonists (laminarin, molecules with terminal mannose, N-Formyl-methioninyl-leucyl-phenylalanine were firmly anchored to the tumor cell surface. When particular agonists of phagocytic receptors were used together with LPS (Toll-like receptor agonist, high synergy causing tumour shrinkage and a temporary or permanent disappearance was observed. Methods of anchoring phagocytic receptor agonists (charge interactions, anchoring based on hydrophobic chains, covalent bonds and various regimes of phagocytic agonist/LPS mixture applications were tested to achieve maximum therapeutic effect. Combinations of mannan/LPS and f-MLF/LPS (hydrophobic anchors in appropriate (pulse regimes resulted in an 80% and 60% recovery for mice, respectively. We propose that substantial synergy between agonists of phagocytic and Toll-like receptors (TLR is based on two events. The TLR ligand induces early and massive inflammatory infiltration of tumors. The effect of this cell infiltrate is directed towards tumor cells, bearing agonists of phagocytic receptors on their surface. The result of these processes was effective killing of tumor cells. This novel approach represents exploitation of innate immunity mechanisms for treating cancer.

  7. [18F]MK-9470 PET measurement of cannabinoid CB1 receptor availability in chronic cannabis users.

    Science.gov (United States)

    Ceccarini, Jenny; Kuepper, Rebecca; Kemels, Dieter; van Os, Jim; Henquet, Cécile; Van Laere, Koen

    2015-03-01

    Δ(9) -Tetrahydrocannabinol, the main psychoactive component of cannabis, exerts its central effects through activation of the cerebral type 1 cannabinoid (CB1 ) receptor. Pre-clinical studies have provided evidence that chronic cannabis exposure is linked to decreased CB1 receptor expression and this is thought to be a component underlying drug tolerance and dependence. In this study, we make first use of the selective high-affinity positron emission tomography (PET) ligand [(18) F]MK-9470 to obtain in vivo measurements of cerebral CB1 receptor availability in 10 chronic cannabis users (age = 26.0 ± 4.1 years). Each patient underwent [(18) F]MK-9470 PET within the first week following the last cannabis consumption. A population of 10 age-matched healthy subjects (age = 23.0 ± 2.9 years) was used as control group. Parametric modified standardized uptake value images, reflecting CB1 receptor availability, were calculated. Statistical parametric mapping and volume-of-interest (VOI) analyses of CB1 receptor availability were performed. Compared with controls, cannabis users showed a global decrease in CB1 receptor availability (-11.7 percent). VOI-based analysis demonstrated that the CB1 receptor decrease was significant in the temporal lobe (-12.7 percent), anterior (-12.6 percent) and posterior cingulate cortex (-13.5 percent) and nucleus accumbens (-11.2 percent). Voxel-based analysis confirmed this decrease and regional pattern in CB1 receptor availability in cannabis users. These findings revealed that chronic cannabis use may alter specific regional CB1 receptor expression through neuroadaptive changes in CB1 receptor availability, opening the way for the examination of specific CB1 -cannabis addiction interactions which may predict future cannabis-related treatment outcome.

  8. Potential antidepressant-like properties of the TC G-1008, a GPR39 (zinc receptor) agonist.

    Science.gov (United States)

    Młyniec, Katarzyna; Starowicz, Gabriela; Gaweł, Magdalena; Frąckiewicz, Ewelina; Nowak, Gabriel

    2016-09-01

    Some forms of depression appear to be more related to the glutamatergic system. G-coupled protein receptor 39 (GPR39) is the metabotropic zinc receptor, which may be involved in the pathophysiology of depression and in the antidepressant response. Its deficiency abolishes the antidepressant response, which means that GPR39 is required to obtain a therapeutic effect in depression. This raises the possibility that agonists of the zinc receptor may have a role in antidepressant treatment. To explore this possibility we investigated animal behaviour in the forced swim test, the tail suspension test (to assess antidepressant-like properties), the light/dark test and the elevated plus maze test (to assess anxiolytic-like properties), following acute administration of a GPR39 agonist (TC G-1008). We found an antidepressant response (as measured by the forced swim test but not by the tail suspension test) in mice following the GPR39 agonist treatment. Additionally, we observed the opposite results in the light/dark box (decreased overall distance; increased time spent in the lit compartment; decreased time spent in the dark compartment; increased freezing time) and elevated plus maze (no significant changes), which may be a consequence of the sedative effect of TC G-1008. We also found hippocampal GPR39 and brain-derived neurotrophic factor (BDNF) up-regulation following administration of the GPR39 agonist, which may be undiscovered so far as a possible novel agent in the treatment of mood disorders. PMID:27235821

  9. Biological characterization of PM226, a chromenoisoxazole, as a selective CB2 receptor agonist with neuroprotective profile.

    Science.gov (United States)

    Gómez-Cañas, M; Morales, P; García-Toscano, L; Navarrete, C; Muñoz, E; Jagerovic, N; Fernández-Ruiz, J; García-Arencibia, M; Pazos, M R

    2016-08-01

    Cannabinoids have emerged as promising neuroprotective agents due to their capability to activate specific targets, which are involved in the control of neuronal homeostasis and survival. Specifically, those ligands that selectively target and activate the CB2 receptor may be useful for their anti-inflammatory and neuroprotective properties in various neurological disorders, with the advantage of being devoid of psychotropic effects associated with the activation of CB1 receptors. The aim of this work has been to investigate the neuroprotective properties of 7-(1,1-dimethylheptyl)-4,4-dimethyl-9-methoxychromeno[3,4-d]isoxazole (PM226), a compound derived from a series of chromeno-isoxazoles and -pyrazoles, which seems to have a promising profile related to the CB2 receptor. The compound binds selectively to this receptor with an affinity in the nanomolar range (Ki=12.8±2.4nM). It has negligible affinity for the CB1 receptor (Ki>40000nM) and no activity at the GPR55. PM226 was also evaluated in GTPγS binding assays specific to the CB2 receptor showing agonist activity (EC50=38.67±6.70nM). In silico analysis of PM226 indicated that it has a good pharmacokinetic profile and a predicted ability to cross the blood-brain barrier. Next, PM226 was investigated in an in vitro model to explore its anti-inflammatory/neuroprotective properties. Conditioned media were collected from LPS-stimulated cultures of BV2 microglial cell line in the absence or presence of different doses of PM226, and then media were added to cultured M213-2O neuronal cells to record their influence on cell viability evaluated using MTT assays. As expected, cell viability was significantly reduced by the exposure to these conditioned media, while the addition of PM226 attenuated this reduction in a dose-dependent manner. This effect was reversed by co-incubating with the CB2 antagonist SR144528, thus confirming the involvement of CB2 receptors, whereas the addition of PM226 to neuronal cultures

  10. Guanine nucleotide regulation of dopamine receptor agonist affinity states in rat estradiol-induced pituitary tumors

    Energy Technology Data Exchange (ETDEWEB)

    Di Paolo, T.; Falardeau, P.

    1987-08-31

    The authors have investigated dopamine (DA) receptor agonist high- and low-affinity states in female rate estradiol-induced prolactin (PRL)-secreting pituitary tumors and intact pituitary tissue. Estradiol treatment increased the anterior pituitary weight 9-fold and plasma prolactin levels 74-fold and these measures are correlated (R = 0.745, n = 73, p < 0.001). Competition for (/sup 3/H)-spiperone binding to the DA receptor by apomorphine was compared in normal and adenomatous pituitary tissue. The inhibition constants (Ki) and the proportions of the two apomorphine sites are unchanged in tumors compared to intact pituitary tissue. Guanosine 5'-(..beta..-..gamma..-imino)triphosphate (Gpp(NH)p) causes complete conversion of the high into low affinity dopaminergic agonist site in normal pituitary and in tumors. These results suggest that rats with primary estradiol-induced pituitary tumors have normal and functional DA receptors. 9 references, 2 tables.

  11. Highly selective and potent agonists of sphingosine-1-phosphate 1 (S1P1) receptor.

    Science.gov (United States)

    Vachal, Petr; Toth, Leslie M; Hale, Jeffrey J; Yan, Lin; Mills, Sander G; Chrebet, Gary L; Koehane, Carol A; Hajdu, Richard; Milligan, James A; Rosenbach, Mark J; Mandala, Suzanne

    2006-07-15

    Novel series of sphingosine-1-phosphate (S1P) receptor agonists were developed through a systematic SAR aimed to achieve high selectivity for a single member of the S1P family of receptors, S1P1. The optimized structure represents a highly S1P1-selective and efficacious agonist: S1P1/S1P2, S1P1/S1P3, S1P1/S1P4>10,000-fold, S1P1/S1P5>600-fold, while EC50 (S1P1) <0.2 nM. In vivo experiments are consistent with S1P1 receptor agonism alone being sufficient for achieving desired lymphocyte-lowering effect.

  12. Dimethyl-diphenyl-propanamide derivatives as nonsteroidal dissociated glucocorticoid receptor agonists.

    Science.gov (United States)

    Yang, Bingwei V; Weinstein, David S; Doweyko, Lidia M; Gong, Hua; Vaccaro, Wayne; Huynh, Tram; Xiao, Hai-Yun; Doweyko, Arthur M; McKay, Lorraine; Holloway, Deborah A; Somerville, John E; Habte, Sium; Cunningham, Mark; McMahon, Michele; Townsend, Robert; Shuster, David; Dodd, John H; Nadler, Steven G; Barrish, Joel C

    2010-12-01

    A series of 2,2-dimethyl-3,3-diphenyl-propanamides as novel glucocorticoid receptor modulators is reported. SAR exploration led to the identification of 4-hydroxyphenyl propanamide derivatives displaying good agonist activity in GR-mediated transrepression assays and reduced agonist activity in GR-mediated transactivation assays. Compounds 17 and 30 showed anti-inflammatory activity comparable to prednisolone in the rat carrageenan-induced paw edema model, with markedly decreased side effects with regard to increases in blood glucose and expression of hepatic tyrosine aminotransferase. A hypothetical binding mode accounting for the induction of the functional activity by a 4-hydroxyl group is proposed. PMID:21073190

  13. High specific activity tritium labelling of some sigma-1 receptor agonists

    International Nuclear Information System (INIS)

    The high specific activity tritiation of (+)-SKF-10,047 (1) and N,N-dimethyltryptamine (4) is described. [N-allyl-3H] (+)-SKF-10,047 (3) was prepared by Lindlar catalyst tritiation of (+)-N-propargylnormetazocine (2) and [N-methyl-3H] N,N-dimethyltryptamine (6) was synthesized by the alkylation of N-methyltryptamine (5) with [3H] methyl iodide. Both sigma-1 synthetic agonist 3 and endogenous agonist 6 have been useful in studying this receptor. (author)

  14. Angiotensin AT2 receptor agonist prevents salt-sensitive hypertension in obese Zucker rats

    OpenAIRE

    Ali, Quaisar; Patel, Sanket; Hussain, Tahir

    2015-01-01

    High-sodium intake is a risk factor for the pathogenesis of hypertension, especially in obesity. The present study is designed to investigate whether angiotensin type 2 receptor (AT2R) activation with selective agonist C21 prevents high-sodium diet (HSD)-induced hypertension in obese animals. Male obese rats were treated with AT2R agonist C21 (1 mg·kg−1·day−1, oral) while maintained on either normal-sodium diet (NSD; 0.4%) or HSD (4%) for 2 wk. Radiotelemetric recording showed a time-dependen...

  15. Intersubunit bridge formation governs agonist efficacy at nicotinic acetylcholine alpha4beta2 receptors

    DEFF Research Database (Denmark)

    Rohde, Line Aagot Hede; Ahring, Philip Kiær; Jensen, Marianne Lerbech;

    2012-01-01

    The a4ß2 subtype of the nicotinic acetylcholine receptor (nAChR) has been pursued as a drug target for treatment of psychiatric and neurodegenerative disorders and smoking cessation aids for decades. Still, a thorough understanding of structure-function relationships of a4ß2 agonists is lacking....... Using binding experiments, electrophysiology and X-ray crystallography we have investigated a consecutive series of five prototypical pyridine-containing agonists derived from 1-(pyridin-3-yl)-1,4-diazepane. A correlation between binding affinities at a4ß2 and the acetylcholine binding protein from...

  16. Agonists of fibroblast growth factor receptor induce neurite outgrowth and survival of cerebellar granule neurons

    DEFF Research Database (Denmark)

    Li, Shizhong; Christensen, Claus; Køhler, Lene B;

    2009-01-01

    Fibroblast growth factor receptor (FGFR) signaling is pivotal in the regulation of neurogenesis, neuronal differentiation and survival, and synaptic plasticity both during development and in adulthood. In order to develop low molecular weight agonists of FGFR, seven peptides, termed hexafins...... phosphorylation, indicating that hexafins act as partial agonists. Hexafin2, 3, 8, 10, and 17 (but not 1 or 9) induced neurite outgrowth from cerebellar granule neurons (CGNs), an effect that was abolished by two inhibitors of FGFR, SU5402 and inositol hexaphosphate (IP6) and a diacylglycerol lipase inhibitor...

  17. Beta-arrestin-mediated activation of MAPK by inverse agonists reveals distinct active conformations for G protein-coupled receptors.

    OpenAIRE

    Azzi, Mounia; Pascale G. Charest; Angers, Stéphane; Rousseau, Guy; Kohout, Trudy; Bouvier, Michel; Piñeyro, Graciela

    2003-01-01

    It is becoming increasingly clear that signaling via G protein-coupled receptors is a diverse phenomenon involving receptor interaction with a variety of signaling partners. Despite this diversity, receptor ligands are commonly classified only according to their ability to modify G protein-dependent signaling. Here we show that beta2AR ligands like ICI118551 and propranolol, which are inverse agonists for Gs-stimulated adenylyl cyclase, induce partial agonist responses for the mitogen-activat...

  18. Spontaneous Cannabinoid Receptor 2 (CB2) Expression in the Cochlea of Adult Albino Rat and Its Up-Regulation after Cisplatin Treatment.

    Science.gov (United States)

    Martín-Saldaña, Sergio; Trinidad, Almudena; Ramil, Elvira; Sánchez-López, Antonio J; Coronado, Maria José; Martínez-Martínez, Esther; García, José Miguel; García-Berrocal, José Ramón; Ramírez-Camacho, Rafael

    2016-01-01

    We provide evidence for the presence of cannabinoid CB2 receptors in some cellular types of the cochlea of the adult albino rat. Cannabinoids and their receptors are increasingly being studied because of their high potential for clinical use. As a hyperspecialized portion of the peripheral nervous system, study of the expression and function of cannabinoid receptors in the hearing organ is of high interest. Stria vascularis and inner hair cells express CB2 receptor, as well as neurites and cell bodies of the spiral ganglion. Cellular types such as supporting cells and outer hair cells, in which the expression of other types of functional receptors has been reported, do not significantly express CB2 receptors in this study. An up-regulation of CB2 gene expression was detected after an ototoxic event such as cisplatin treatment, probably due to pro-inflammatory events triggered by the drug. That fact suggests promising potential of CB2 receptor as a therapeutic target for new treatments to palliate cisplatin-induced hearing loss and other ototoxic events which triggers inflammatory pathways. PMID:27564061

  19. Partial agonists and subunit selectivity at NMDA receptors

    DEFF Research Database (Denmark)

    Risgaard, Rune; Hansen, Kasper Bø; Clausen, Rasmus Prætorius

    2010-01-01

    Subunit-selective ligands for glutamate receptors remains an area of interest as glutamate is the major excitatory neurotransmitter in the brain and involved in a number of diseased states in the central nervous system (CNS). Few subtype-selective ligands are known, especially among the N-methyl-...

  20. Principles of agonist recognition in Cys-loop receptors

    DEFF Research Database (Denmark)

    Lynagh, Timothy Peter; Pless, Stephan Alexander

    2014-01-01

    Cys-loop receptors are ligand-gated ion channels that are activated by a structurally diverse array of neurotransmitters, including acetylcholine, serotonin, glycine, and GABA. After the term "chemoreceptor" emerged over 100 years ago, there was some wait until affinity labeling, molecular cloning...

  1. Synthesis and enantiopharmacology of new AMPA-kainate receptor agonists

    DEFF Research Database (Denmark)

    Conti, P; De Amici, M; De Sarro, G;

    1999-01-01

    , and the rat cortical wedge preparation. CIP-A showed a good affinity for both 2-amino-3-(3-hydroxy-5-methylisoxazol-4-yl)propionic acid (AMPA) and kainic acid (KAIN) receptors. These results were confirmed in the cortical slice model where CIP-A displayed an EC(50) value very close to that of AMPA...

  2. Ah receptor agonist activity in frequently consumed food items

    NARCIS (Netherlands)

    Waard, de W.J.; Aarts, J.M.M.J.G.; Peijnenburg, A.A.C.M.; Kok, de T.M.C.M.; Schooten, van F.J.; Hoogenboom, L.A.P.

    2008-01-01

    The aryl hydrocarbon receptor (AhR) receives much attention for its role in the toxicity of dioxins and dioxin-like polychlorinated biphenyls. However, many other compounds have also been reported to bind and activate AhR, of which natural food components are of special interest from a human health

  3. Pharmacological characterization of a selective agonist for Bombesin Receptor Subtype - 3

    OpenAIRE

    Zhang, Li; Nothacker, Hans-Peter; Wang, Zhiwei; Bohn, Laura M.; Civelli, Olivier

    2009-01-01

    Bombesin receptor subtype-3 (BRS-3) is an orphan G protein-coupled receptor in the bombesin receptor family that still awaits identification of its natural ligand. BRS-3 deficient mice develop a mild late-onset obesity with metabolic defects, implicating BRS-3 plays a role in feeding and metabolism. We describe here the pharmacological characterization of a synthetic compound, 16a, which serves as a potent agonist for BRS-3. This compound is selective for BRS-3 as it does not activate neurome...

  4. Full and partial agonists of thromboxane prostanoid receptor unveil fine tuning of receptor superactive conformation and G protein activation.

    Directory of Open Access Journals (Sweden)

    Valérie Capra

    Full Text Available The intrahelical salt bridge between E/D(3.49 and R(3.50 within the E/DRY motif on helix 3 (H3 and the interhelical hydrogen bonding between the E/DRY and residues on H6 are thought to be critical in stabilizing the class A G protein-coupled receptors in their inactive state. Removal of these interactions is expected to generate constitutively active receptors. This study examines how neutralization of E(3.49/6.30 in the thromboxane prostanoid (TP receptor alters ligand binding, basal, and agonist-induced activity and investigates the molecular mechanisms of G protein activation. We demonstrate here that a panel of full and partial agonists showed an increase in affinity and potency for E129V and E240V mutants. Yet, even augmenting the sensitivity to detect constitutive activity (CA with overexpression of the receptor or the G protein revealed resistance to an increase in basal activity, while retaining fully the ability to cause agonist-induced signaling. However, direct G protein activation measured through bioluminescence resonance energy transfer (BRET indicates that these mutants more efficiently communicate and/or activate their cognate G proteins. These results suggest the existence of additional constrains governing the shift of TP receptor to its active state, together with an increase propensity of these mutants to agonist-induced signaling, corroborating their definition as superactive mutants. The particular nature of the TP receptor as somehow "resistant" to CA should be examined in the context of its pathophysiological role in the cardiovascular system. Evolutionary forces may have favored regulation mechanisms leading to low basal activity and selected against more highly active phenotypes.

  5. Human Laboratory Studies on Cannabinoids and Psychosis.

    Science.gov (United States)

    Sherif, Mohamed; Radhakrishnan, Rajiv; D'Souza, Deepak Cyril; Ranganathan, Mohini

    2016-04-01

    Some of the most compelling evidence supporting an association between cannabinoid agonists and psychosis comes from controlled laboratory studies in humans. Randomized, double-blind, placebo-controlled, crossover laboratory studies demonstrate that cannabinoid agonists, including phytocannabinoids and synthetic cannabinoids, produce a wide range of positive, negative, and cognitive symptoms and psychophysiologic deficits in healthy human subjects that resemble the phenomenology of schizophrenia. These effects are time locked to drug administration, are dose related, and are transient and rarely necessitate intervention. The magnitude of effects is similar to the effects of ketamine but qualitatively distinct from other psychotomimetic drugs, including ketamine, amphetamine, and salvinorin A. Cannabinoid agonists have also been shown to transiently exacerbate symptoms in individuals with schizophrenia in laboratory studies. Patients with schizophrenia are more vulnerable than healthy control subjects to the acute behavioral and cognitive effects of cannabinoid agonists and experience transient exacerbation of symptoms despite treatment with antipsychotic medications. Furthermore, laboratory studies have failed to demonstrate any "beneficial" effects of cannabinoid agonists in individuals with schizophrenia-challenging the cannabis self-medication hypothesis. Emerging evidence suggests that polymorphisms of several genes related to dopamine metabolism (e.g., COMT, DAT1, and AKT1) may moderate the effects of cannabinoid agonists in laboratory studies. Cannabinoid agonists induce dopamine release, although the magnitude of release does not appear to be commensurate to the magnitude and spectrum of their acute psychotomimetic effects. Interactions between the endocannabinoid, gamma-aminobutyric acid, and glutamate systems and their individual and interactive effects on neural oscillations provide a plausible mechanism underlying the psychotomimetic effects of

  6. Metabotropic glutamate receptor agonists potentiate a slow afterdepolarization in CNS neurons

    Science.gov (United States)

    Zheng, F.; Gallagher, J. P.

    1992-01-01

    We have previously reported that, in the rat dorsolateral septal nucleus (DLSN), metabotropic glutamate receptor (met-GluR) agonists evoked a slow depolarization accompanied by an increase in membrane conductance and burst firing. We have speculated that the burst firing elicited by met-GluR agonists may be due to activation or enhancement of a non-specific cation current, which exists in some DLSN neurons. Now we report that a slow afterdepolarization (sADP) mediated by a non-specific cation current was potentiated by both 1S,3R-ACPD and quisqualate. In addition, met-GluR agonists unmask a sADP in DLSN neurons which did not show a sADP under control conditions. Our data suggest that a non-specific cation current can be potentiated by activation of the met-GluR.

  7. Diverging mechanisms of activation of chemokine receptors revealed by novel chemokine agonists.

    Directory of Open Access Journals (Sweden)

    Jose Sarmiento

    Full Text Available CXCL8/interleukin-8 is a pro-inflammatory chemokine that triggers pleiotropic responses, including inflammation, angiogenesis, wound healing and tumorigenesis. We engineered the first selective CXCR1 agonists on the basis of residue substitutions in the conserved ELR triad and CXC motif of CXCL8. Our data reveal that the molecular mechanisms of activation of CXCR1 and CXCR2 are distinct: the N-loop of CXCL8 is the major determinant for CXCR1 activation, whereas the N-terminus of CXCL8 (ELR and CXC is essential for CXCR2 activation. We also found that activation of CXCR1 cross-desensitized CXCR2 responses in human neutrophils co-expressing both receptors, indicating that these novel CXCR1 agonists represent a new class of anti-inflammatory agents. Further, these selective CXCR1 agonists will aid at elucidating the functional significance of CXCR1 in vivo under pathophysiological conditions.

  8. Endurance training in Wistar rats decreases receptor sensitivity to a serotonin agonist.

    Science.gov (United States)

    Dwyer, D; Browning, J

    2000-11-01

    There is mounting evidence that increased brain serotonin during exercise is associated with the onset of CNS-mediated fatigue. Serotonin receptor sensitivity is likely to be an important determinant of this fatigue. Alterations in brain serotonin receptor sensitivity were examined in Wistar rats throughout 6 weeks of endurance training, running on a treadmill four times a week with two exercise tests per week to exhaustion. Receptor sensitivity was determined indirectly as the reduction in exercise time in response to a dose of a serotonin (1A) agonist, m-chlorophenylpiperazine (m-CPP). The two groups of controls were used to examine (i) the effect of the injection per se on exercise performance and (ii) changes in serotonin receptor sensitivity associated with maturation. In the test group, undrugged exercise performance significantly improved by 47% after 6 weeks of training (4518 +/- 729 to 6640 +/- 903 s, P=0.01). Drugged exercise performance also increased significantly from week 1 to week 6 (306 +/- 69-712 +/- 192 s, P = 0.04). Control group results indicated that the dose of m-CPP alone caused fatigue during exercise tests and that maturation was not responsible for any decrease in receptor sensitivity. Improved resistance to the fatiguing effects of the serotonin agonist suggests desensitization of central serotonin receptors, probably the 5-HT1A receptors. Endurance training appears to stimulate an adaptive response to the fatiguing effects of increased brain serotonin, which may enhance endurance exercise performance. PMID:11167306

  9. Cannabinoids enhance gastric X/A-like cells activity.

    Directory of Open Access Journals (Sweden)

    Bogusław Sawicki

    2008-06-01

    Full Text Available It has been reported that cannabinoids may cause overeating in humans and in laboratory animals. Although, endogenous cannabinoids and their receptors (CB1 have been found in the hypothalamus, and recently also in gastrointestinal tract, the precise mechanism of appetite control by cannabinoids remains unknown. Recently, ghrelin--a hormone secreted mainly from the stomach X/A-like cells was proposed to be an appetite stimulating agent. The aim of this study was the evaluation of the influence of a single ip injection of a stable analogue of endogenous cannabinoid--anandamide, R-(+-methanandamide (2.5 mg/kg and CP 55,940 (0.25 mg/kg, an exogenous agonist of CB1 receptors, on ghrelin plasma concentration and on ghrelin immunoreactivity in the gastric mucosa of male Wistar rats. Four hours after a single injection of both cannabinoids or vehicle, the animals were anaesthetized and blood was taken from the abdominal aorta to determinate plasma ghrelin concentration by RIA. Subsequently, the animals underwent resection of distal part of stomach. Immunohistochemical study of gastric mucosa, using the EnVision method and specific monoclonal antibodies against ghrelin was performed. The intensity of ghrelin immunoreactivity in X/A-like cells was analyzed using Olympus Cell D image analysis system. The attenuation of ghrelin-immunoreactivity of gastric mucosa, after a single injection of R-(+-methanandamide and CP 55,940 was accompanied by a significant increase of ghrelin plasma concentration. These results indicate that stimulation of appetite exerted by cannabinoids may be connected with an increase of ghrelin secretion from gastric X/A-like cells.

  10. The role of cannabinoids and leptin in neurological diseases.

    Science.gov (United States)

    Agar, E

    2015-12-01

    Cannabinoids exert a neuroprotective influence on some neurological diseases, including Alzheimer's, Parkinson's, Huntington's, multiple sclerosis and epilepsy. Synthetic cannabinoid receptor agonists/antagonists or compounds can provide symptom relief or control the progression of neurological diseases. However, the molecular mechanism and the effectiveness of these agents in controlling the progression of most of these diseases remain unclear. Cannabinoids may exert effects via a number of mechanisms and interactions with neurotransmitters, neurotropic factors and neuropeptides. Leptin is a peptide hormone involved in the regulation of food intake and energy balance via its actions on specific hypothalamic nuclei. Leptin receptors are widely expressed throughout the brain, especially in the hippocampus, basal ganglia, cortex and cerebellum. Leptin has also shown neuroprotective properties in a number of neurological disorders, such as Parkinson's and Alzheimer's. Therefore, cannabinoid and leptin hold therapeutic potential for neurological diseases. Further elucidation of the molecular mechanisms underlying the effects on these agents may lead to the development of new therapeutic strategies for the treatment of neurological disorders. PMID:25880465

  11. Classification of 5-HT1A receptor agonists and antagonists using GA-SVM method

    Institute of Scientific and Technical Information of China (English)

    Xue-lian ZHU; Hai-yan CAI; Zhi-jian XU; Yong WANG; He-yao WANG; Ao ZHANG; Wei-liang ZHU

    2011-01-01

    Aim:To construct a reliable computational model for the classification of agonists and antagonists of 5-HT1A receptor.Methods:Support vector machine (SVM),a well-known machine learning method,was employed to build a prediction model,and genetic algorithm (GA) was used to select the most relevant descriptors and to optimize two important parameters,C and r of the SVM model.The overall dataset used in this study comprised 284 ligands of the 5-HT1A receptor with diverse structures reported in the literatures.Results:A SVM model was successfully developed that could be used to predict the probability of a ligand being an agonist or antagonist of the 5-HT1A receptor.The predictive accuracy for training and test sets was 0.942 and 0.865,respectively.For compounds with probability estimate higher than 0.7,the predictive accuracy of the model for training and test sets was 0.954 and 0.927,respectively.To further validate our model,the receiver operating characteristic (ROC) curve was plotted,and the Area-Under-the-ROC-Curve (AUC) value was calculated to be 0.883 for training set and 0.906 for test set.Conclusion:A reliable SVM model was successfully developed that could effectively distinguish agonists and antagonists among the ligands of the 5-HT1A receptor.To our knowledge,this is the first effort for the classification of 5-HT1A receptor agonists and antagonists based on a diverse dataset.This method may be used to classify the ligands of other members of the GPCR family.

  12. Antitussive activity of sigma-1 receptor agonists in the guinea-pig

    Science.gov (United States)

    Brown, Claire; Fezoui, Malika; Selig, William M; Schwartz, Carl E; Ellis, James L

    2003-01-01

    Current antitussive medications have limited efficacy and often contain the opiate-like agent dextromethorphan (DEX). The mechanism whereby DEX inhibits cough is ill defined. DEX displays affinity at both NMDA and sigma receptors, suggesting that the antitussive activity may involve central or peripheral activity at either of these receptors. This study examined and compared the antitussive activity of DEX and various putative sigma receptor agonists in the guinea-pig citric-acid cough model. Intraperitoneal (i.p.) administration of DEX (30 mg kg−1) and the sigma-1 agonists SKF-10,047 (1–5 mg kg−1), Pre-084 (5 mg kg−1), and carbetapentane (1–5 mg kg−1) inhibited citric-acid-induced cough in guinea-pigs. Intraperitoneal administration of a sigma-1 antagonist, BD 1047 (1–5 mg kg−1), reversed the inhibition of cough elicited by SKF-10,047. In addition, two structurally dissimilar sigma agonists SKF-10,047 (1 mg ml−1) and Pre-084 (1 mg ml−1) inhibited cough when administered by aerosol. Aerosolized BD 1047 (1 mg ml−1, 30 min) prevented the antitussive action of SKF-10,047 (5 mg kg−1) or DEX (30 mg kg−1) given by i.p. administration and, likewise, i.p. administration of BD 1047 (5 mg kg−1) prevented the antitussive action of SKF-10,047 given by aerosol (1 mg ml−1). These results therefore support the argument that antitussive effects of DEX may be mediated via sigma receptors, since both systemic and aerosol administration of sigma-1 receptor agonists inhibit citric-acid-induced cough in guinea-pigs. While significant systemic exposure is possible with aerosol administration, the very low doses administered (estimated <0.3 mg kg−1) suggest that there may be a peripheral component to the antitussive effect. PMID:14691051

  13. Distinct Signaling Cascades Elicited by Different Formyl Peptide Receptor 2 (FPR2 Agonists

    Directory of Open Access Journals (Sweden)

    Fabio Cattaneo

    2013-04-01

    Full Text Available The formyl peptide receptor 2 (FPR2 is a remarkably versatile transmembrane protein belonging to the G-protein coupled receptor (GPCR family. FPR2 is activated by an array of ligands, which include structurally unrelated lipids and peptide/proteins agonists, resulting in different intracellular responses in a ligand-specific fashion. In addition to the anti-inflammatory lipid, lipoxin A4, several other endogenous agonists also bind FPR2, including serum amyloid A, glucocorticoid-induced annexin 1, urokinase and its receptor, suggesting that the activation of FPR2 may result in potent pro- or anti-inflammatory responses. Other endogenous ligands, also present in biological samples, include resolvins, amyloidogenic proteins, such as beta amyloid (Aβ-42 and prion protein (Prp106–126, the neuroprotective peptide, humanin, antibacterial peptides, annexin 1-derived peptides, chemokine variants, the neuropeptides, vasoactive intestinal peptide (VIP and pituitary adenylate cyclase activating polypeptide (PACAP-27, and mitochondrial peptides. Upon activation, intracellular domains of FPR2 mediate signaling to G-proteins, which trigger several agonist-dependent signal transduction pathways, including activation of phospholipase C (PLC, protein kinase C (PKC isoforms, the phosphoinositide 3-kinase (PI3K/protein kinase B (Akt pathway, the mitogen-activated protein kinase (MAPK pathway, p38MAPK, as well as the phosphorylation of cytosolic tyrosine kinases, tyrosine kinase receptor transactivation, phosphorylation and nuclear translocation of regulatory transcriptional factors, release of calcium and production of oxidants. FPR2 is an attractive therapeutic target, because of its involvement in a range of normal physiological processes and pathological diseases. Here, we review and discuss the most significant findings on the intracellular pathways and on the cross-communication between FPR2 and tyrosine kinase receptors triggered by different FPR2

  14. Functional potencies of dopamine agonists and antagonists at human dopamine D₂ and D₃ receptors.

    Science.gov (United States)

    Tadori, Yoshihiro; Forbes, Robert A; McQuade, Robert D; Kikuchi, Tetsuro

    2011-09-01

    We measured the functional agonist potencies of dopamine agonists including antiparkinson drugs, and functional antagonist potencies of antipsychotics at human dopamine D(2) and D(3) receptors. In vitro pharmacological assessment included inhibition of forskolin-stimulated cAMP accumulation and the reversal of dopamine-induced inhibition in clonal Chinese hamster ovary cells expressing low and high densities of human dopamine D(2L) and D(2S) receptors (hD(2L)-Low, hD(2L)-High, hD(2S)-Low and hD(2S)-High, respectively) and human dopamine D(3) Ser-9 and D(3) Gly-9 receptors (hD(3)-Ser-9 and hD(3)-Gly-9, respectively). Cabergoline, bromocriptine, pergolide, (±)-7-hydroxy-N,N-di-n-propyl-2-aminotetralin (7-OH-DPAT), talipexole, pramipexole, R-(+)-trans-3,4,4a,10b-tetrahydro-4-propyl-2H,5H-[1]benzopyrano[4,3-b]-1,4-oxazin-9-olhydrochloride (PD128907) and ropinirole behaved as dopamine D(2) and D(3) receptor full agonists and showed higher potencies in hD(2L)-High and hD(2S)-High compared to hD(2L)-Low and hD(2S)-Low. In hD(3)-Ser-9 and hD(3)-Gly-9 compared to hD(2L)-Low and hD(2S)-Low, dopamine, ropinirole, PD128907, and pramipexole potencies were clearly higher; talipexole and 7-OH-DPAT showed slightly higher potencies; pergolide showed slightly lower potency; and, cabergoline and bromocriptine potencies were lower. Aripiprazole acted as an antagonist in hD(2L)-Low; a low intrinsic activity partial agonist in hD(2S)-Low; a moderate partial agonist in hD(3)-Ser-9 and hD(3)-Gly-9; a robust partial agonist in hD(2L)-High; and a full agonist in hD(2S)-High. Amisulpride, sulpiride and perphenazine behaved as preferential antagonists; and chlorpromazine and asenapine behaved as modest preferential antagonists; whereas fluphenazine, haloperidol, and blonanserin behaved as non-preferential antagonists in hD(2S)-Low and hD(2S)-High compared to hD(3)-Ser-9 and hD(3)-Gly-9. These findings may help to elucidate the basis of therapeutic benefit observed with these drugs, with

  15. Metabotropic glutamate receptor agonists modify the pyloric output of the crustacean stomatogastric ganglion.

    Science.gov (United States)

    Pérez-Acevedo, Nivia L; Krenz, Wulf D

    2005-11-16

    We have studied the effects of groups I, II, and III metabotropic glutamate receptor (mGluR) agonists and antagonists on pyloric activity in the stomatogastric ganglion (STG) of the Caribbean spiny lobster Panulirus argus. We have found that agonists for all three groups of mGluRs modify the pyloric output. The group I agonist, l-quisqualic acid (l-QA), activated the pyloric central pattern generator (CPG). When the pyloric rhythm was partially suppressed by sucrose-block of input fibers in the stomatogastric nerve (stn), l-QA accelerated the rhythmic activity. In addition, the number of spike discharges was increased in pyloric motoneurons: pyloric (PY), and lateral pyloric (LP). In completely blocked preparations, a slow pyloric rhythm was initiated by l-QA. Groups II and III agonists exerted an inhibitory effect on pyloric activity. The group II agonist, (2S,1'S,2'S)-2-(Carboxycyclopropyl)glycine (L-CCG-I), decreased both the frequency of the pyloric rhythm and the number of spike discharges in the motoneurons: ventricular dilator (VD), PY, and LP. The effects of L-CCG-I were dose-dependent. The group III agonist, l-(+)-2-Amino-4-phosphonobutyric acid (l-AP4), slightly decreased the frequency of the pyloric rhythm and suppressed spike discharges in the VD neuron. All effects of mGluR agonists were reversible. The effect of l-QA was blocked by the broad spectrum mGluR antagonist (S)-Methyl-4-carboxyphenylglycine (MCPG). The inhibitory effect of L-CCG-I was prevented by MCPG and by the group II/III mGluR antagonist (RS)-alpha-Methyl-4-phosphonophenylglycine (MPPG), and was partially blocked by the group II mGluR antagonist (RS)-1-amino-5-phosphonoindan-1-carboxylic acid (APICA). The inhibitory effect of l-AP4 was blocked by MPPG and partially blocked by APICA. PMID:16256086

  16. Dissociated nonsteroidal glucocorticoid receptor modulators; discovery of the agonist trigger in a tetrahydronaphthalene-benzoxazine series.

    Science.gov (United States)

    Barker, Mike; Clackers, Margaret; Copley, Royston; Demaine, Derek A; Humphreys, Davina; Inglis, Graham G A; Johnston, Michael J; Jones, Haydn T; Haase, Michael V; House, David; Loiseau, Richard; Nisbet, Lesley; Pacquet, Francois; Skone, Philip A; Shanahan, Stephen E; Tape, Dan; Vinader, Victoria M; Washington, Melanie; Uings, Iain; Upton, Richard; McLay, Iain M; Macdonald, Simon J F

    2006-07-13

    The tetrahydronaphthalene-benzoxazine glucocorticoid receptor (GR) partial agonist 4b was optimized to produce potent full agonists of GR. Aromatic ring substitution of the tetrahydronaphthalene leads to weak GR antagonists. Discovery of an "agonist trigger" substituent on the saturated ring of the tetrahydronaphthalene leads to increased potency and efficacious GR agonism. These compounds are efficacy selective in an NFkB GR agonist assay (representing transrepression effects) over an MMTV GR agonist assay (representing transactivation effects). 52 and 60 have NFkB pIC(50) = 8.92 (105%) and 8.69 (92%) and MMTV pEC(50) = 8.20 (47%) and 7.75 (39%), respectively. The impact of the trigger substituent on agonism is modeled within GR and discussed. 36, 52, and 60 have anti-inflammatory activity in a mouse model of inflammation after topical dosing with 52 and 60, having an effect similar to that of dexamethasone. The original lead was discovered by a manual agreement docking method, and automation of this method is also described. PMID:16821781

  17. Modulation Effect of Peroxisome Proliferator-Activated Receptor Agonists on Lipid Droplet Proteins in Liver.

    Science.gov (United States)

    Zhu, Yun-Xia; Zhang, Ming-Liang; Zhong, Yuan; Wang, Chen; Jia, Wei-Ping

    2016-01-01

    Peroxisome proliferator-activated receptor (PPAR) agonists are used for treating hyperglycemia and type 2 diabetes. However, the mechanism of action of these agonists is still under investigation. The lipid droplet-associated proteins FSP27/CIDEC and LSDP5, regulated directly by PPARγ and PPARα, are associated with hepatic steatosis and insulin sensitivity. Here, we evaluated the expression levels of FSP27/CIDEC and LSDP5 and the regulation of these proteins by consumption of a high-fat diet (HFD) or administration of PPAR agonists. Mice with diet-induced obesity were treated with the PPARγ or PPARα agonist, pioglitazone or fenofibrate, respectively. Liver tissues from db/db diabetic mice and human were also collected. Interestingly, FSP27/CIEDC was expressed in mouse and human livers and was upregulated in obese C57BL/6J mice. Fenofibrate treatment decreased hepatic triglyceride (TG) content and FSP27/CIDEC protein expression in mice fed an HFD diet. In mice, LSDP5 was not detected, even in the context of insulin resistance or treatment with PPAR agonists. However, LSDP5 was highly expressed in humans, with elevated expression observed in the fatty liver. We concluded that fenofibrate greatly decreased hepatic TG content and FSP27/CIDEC protein expression in mice fed an HFD, suggesting a potential regulatory role for fenofibrate in the amelioration of hepatic steatosis.

  18. Systemic administration of the neurotensin NTS1 receptor agonist PD149163 improves performance on a memory task in naturally deficient male Brown Norway rats

    OpenAIRE

    Keiser, Ashley A.; Matazel, Katelin S.; Esser, Melissa K.; Feifel, David; Prus, Adam J.

    2014-01-01

    Agonists for neurotensin NTS1 receptor consistently exhibit antipsychotic effects in animal models without producing catalepsy, suggesting that NTS1 receptor agonists may be a novel class of drugs to treat schizophrenia. Moreover, studies utilizing NTS1 agonists have reported improvements in some aspects of cognitive functioning, including prepulse inhibition and learning procedures, that suggest an ability of NTS1 receptor agonists to diminish neurocognitive deficits. The present study sough...

  19. Synthesis and Preliminary Evaluation of a 2-Oxoquinoline Carboxylic Acid Derivative for PET Imaging the Cannabinoid Type 2 Receptor

    Directory of Open Access Journals (Sweden)

    Linjing Mu

    2014-03-01

    Full Text Available Cannabinoid receptor subtype 2 (CB2 has been shown to be up-regulated in activated microglia and therefore plays an important role in neuroinflammatory and neurodegenerative diseases such as multiple sclerosis, amyotrophic lateral sclerosis and Alzheimer’s disease. The CB2 receptor is therefore considered as a very promising target for therapeutic approaches as well as for imaging. A promising 2-oxoquinoline derivative designated KP23 was synthesized and radiolabeled and its potential as a ligand for PET imaging the CB2 receptor was evaluated. [11C]KP23 was obtained in 10%–25% radiochemical yield (decay corrected and 99% radiochemical purity. It showed high stability in phosphate buffer, rat and mouse plasma. In vitro autoradiography of rat and mouse spleen slices, as spleen expresses a high physiological expression of CB2 receptors, demonstrated that [11C]KP23 exhibits specific binding towards CB2. High spleen uptake of [11C]KP23 was observed in dynamic in vivo PET studies with Wistar rats. In conclusion, [11C]KP23 showed promising in vitro and in vivo characteristics. Further evaluation with diseased animal model which has higher CB2 expression levels in the brain is warranted.

  20. Cannabinoid-Induced Hyperemesis: A Conundrum—From Clinical Recognition to Basic Science Mechanisms

    Directory of Open Access Journals (Sweden)

    Nissar A. Darmani

    2010-07-01

    Full Text Available Cannabinoids are used clinically on a subacute basis as prophylactic agonist antiemetics for the prevention of nausea and vomiting caused by chemotherapeutics. Cannabinoids prevent vomiting by inhibition of release of emetic neurotransmitters via stimulation of presynaptic cannabinoid CB1 receptors. Cannabis-induced hyperemesis is a recently recognized syndrome associated with chronic cannabis use. It is characterized by repeated cyclical vomiting and learned compulsive hot water bathing behavior. Although considered rare, recent international publications of numerous case reports suggest the contrary. The syndrome appears to be a paradox and the pathophysiological mechanism(s underlying the induced vomiting remains unknown. Although some traditional hypotheses have already been proposed, the present review critically explores the basic science of these explanations in the clinical setting and provides more current mechanisms for the induced hyperemesis. These encompass: (1 pharmacokinetic factors such as long half-life, chronic exposure, lipid solubility, individual variation in metabolism/excretion leading to accumulation of emetogenic cannabinoid metabolites, and/or cannabinoid withdrawal; and (2 pharmacodynamic factors including switching of the efficacy of Δ9-THC from partial agonist to antagonist, differential interaction of Δ9-THC with Gs and Gi signal transduction proteins, CB1 receptor desensitization or downregulation, alterations in tissue concentrations of endocannabinoid agonists/inverse agonists, Δ9-THC-induced mobilization of emetogenic metabolites of the arachidonic acid cascade, brainstem versus enteric actions of Δ9-THC, and/or hypothermic versus hyperthermic actions of Δ9-THC. In addition, human and animal findings suggest that chronic exposure to cannabis may not be a prerequisite for the induction of vomiting but is required for the intensity of emesis.

  1. The maintenance of cisplatin- and paclitaxel-induced mechanical and cold allodynia is suppressed by cannabinoid CB2 receptor activation and independent of CXCR4 signaling in models of chemotherapy-induced peripheral neuropathy

    Directory of Open Access Journals (Sweden)

    Deng Liting

    2012-09-01

    Full Text Available Abstract Background Chemotherapeutic agents produce dose-limiting peripheral neuropathy through mechanisms that remain poorly understood. We previously showed that AM1710, a cannabilactone CB2 agonist, produces antinociception without producing central nervous system (CNS-associated side effects. The present study was conducted to examine the antinociceptive effect of AM1710 in rodent models of neuropathic pain evoked by diverse chemotherapeutic agents (cisplatin and paclitaxel. A secondary objective was to investigate the potential contribution of alpha-chemokine receptor (CXCR4 signaling to both chemotherapy-induced neuropathy and CB2 agonist efficacy. Results AM1710 (0.1, 1 or 5 mg/kg i.p. suppressed the maintenance of mechanical and cold allodynia in the cisplatin and paclitaxel models. Anti-allodynic effects of AM1710 were blocked by the CB2 antagonist AM630 (3 mg/kg i.p., but not the CB1 antagonist AM251 (3 mg/kg i.p., consistent with a CB2-mediated effect. By contrast, blockade of CXCR4 signaling with its receptor antagonist AMD3100 (10 mg/kg i.p. failed to attenuate mechanical or cold hypersensitivity induced by either cisplatin or paclitaxel. Moreover, blockade of CXCR4 signaling failed to alter the anti-allodynic effects of AM1710 in the paclitaxel model, further suggesting distinct mechanisms of action. Conclusions Our results indicate that activation of cannabinoid CB2 receptors by AM1710 suppresses both mechanical and cold allodynia in two distinct models of chemotherapy-induced neuropathic pain. By contrast, CXCR4 signaling does not contribute to the maintenance of chemotherapy-induced established neuropathy or efficacy of AM1710. Our studies suggest that CB2 receptors represent a promising therapeutic target for the treatment of toxic neuropathies produced by cisplatin and paclitaxel chemotherapeutic agents.

  2. Discovery of selective hexapeptide agonists to human neuromedin U receptors types 1 and 2.

    Science.gov (United States)

    Takayama, Kentaro; Mori, Kenji; Taketa, Koji; Taguchi, Akihiro; Yakushiji, Fumika; Minamino, Naoto; Miyazato, Mikiya; Kangawa, Kenji; Hayashi, Yoshio

    2014-08-14

    Neuromedin U (NMU) are bioactive peptides with a common C-terminal heptapeptide sequence (FLFRPRN-amide, 1a) among mammals, which is responsible for receptor activation, namely NMU receptor types 1 (NMUR1) and 2 (NMUR2). Among the various physiological actions of NMU, the anorexigenic effect has recently attracted attention in drug discovery efforts for treating obesity. Although several structure-activity relationship (SAR) studies have been reported, receptor-selective small peptide agonists have yet to be disclosed. Herein a SAR study of 1a-derived peptide derivatives is described. We initially screened both human NMUR1- and NMUR2-selective peptides in calcium-mobilization assays with cells transiently expressing receptors. Then we performed a precise assay with a stable expression system of receptors and consequently discovered hexapeptides 8d and 6b possessing selective agonist activity toward each respective receptor. Hexapeptide 6b, which selectively activates NMUR2 without significant NMUR1 activation, should aid in the development of anorexigenic drugs as well as advance NMU-related endocrinological research. PMID:24999562

  3. Differential Rho-kinase dependency of full and partial muscarinic receptor agonists in airway smooth muscle contraction

    NARCIS (Netherlands)

    Schaafsma, D; Boterman, M; de Jong, AM; Hovens, Iris; Penninks, JM; Nelemans, SA; Meurs, H; Zaagsma, J

    2006-01-01

    1 In airway smooth muscle (ASM), full and partial muscarinic receptor agonists have been described to have large differences in their ability to induce signal transduction, including Ca2+-mobilization. Despite these differences, partial agonists are capable of inducing a submaximal to maximal ASM co

  4. Pharmacological Blockade of Cannabinoid CB1 Receptors in Diet-Induced Obesity Regulates Mitochondrial Dihydrolipoamide Dehydrogenase in Muscle.

    Directory of Open Access Journals (Sweden)

    Sergio Arrabal

    Full Text Available Cannabinoid CB1 receptors peripherally modulate energy metabolism. Here, we investigated the role of CB1 receptors in the expression of glucose/pyruvate/tricarboxylic acid (TCA metabolism in rat abdominal muscle. Dihydrolipoamide dehydrogenase (DLD, a flavoprotein component (E3 of α-ketoacid dehydrogenase complexes with diaphorase activity in mitochondria, was specifically analyzed. After assessing the effectiveness of the CB1 receptor antagonist AM251 (3 mg kg(-1, 14 days on food intake and body weight, we could identified seven key enzymes from either glycolytic pathway or TCA cycle--regulated by both diet and CB1 receptor activity--through comprehensive proteomic approaches involving two-dimensional electrophoresis and MALDI-TOF/LC-ESI trap mass spectrometry. These enzymes were glucose 6-phosphate isomerase (GPI, triosephosphate isomerase (TPI, enolase (Eno3, lactate dehydrogenase (LDHa, glyoxalase-1 (Glo1 and the mitochondrial DLD, whose expressions were modified by AM251 in hypercaloric diet-induced obesity. Specifically, AM251 blocked high-carbohydrate diet (HCD-induced expression of GPI, TPI, Eno3 and LDHa, suggesting a down-regulation of glucose/pyruvate/lactate pathways under glucose availability. AM251 reversed the HCD-inhibited expression of Glo1 and DLD in the muscle, and the DLD and CB1 receptor expression in the mitochondrial fraction. Interestingly, we identified the presence of CB1 receptors at the membrane of striate muscle mitochondria. DLD over-expression was confirmed in muscle of CB1-/- mice. AM251 increased the pyruvate dehydrogenase and glutathione reductase activity in C2C12 myotubes, and the diaphorase/oxidative activity in the mitochondria fraction. These results indicated an up-regulation of methylglyoxal and TCA cycle activity. Findings suggest that CB1 receptors in muscle modulate glucose/pyruvate/lactate pathways and mitochondrial oxidative activity by targeting DLD.

  5. Pharmacological Blockade of Cannabinoid CB1 Receptors in Diet-Induced Obesity Regulates Mitochondrial Dihydrolipoamide Dehydrogenase in Muscle.

    Science.gov (United States)

    Arrabal, Sergio; Lucena, Miguel Angel; Canduela, Miren Josune; Ramos-Uriarte, Almudena; Rivera, Patricia; Serrano, Antonia; Pavón, Francisco Javier; Decara, Juan; Vargas, Antonio; Baixeras, Elena; Martín-Rufián, Mercedes; Márquez, Javier; Fernández-Llébrez, Pedro; De Roos, Baukje; Grandes, Pedro; Rodríguez de Fonseca, Fernando; Suárez, Juan

    2015-01-01

    Cannabinoid CB1 receptors peripherally modulate energy metabolism. Here, we investigated the role of CB1 receptors in the expression of glucose/pyruvate/tricarboxylic acid (TCA) metabolism in rat abdominal muscle. Dihydrolipoamide dehydrogenase (DLD), a flavoprotein component (E3) of α-ketoacid dehydrogenase complexes with diaphorase activity in mitochondria, was specifically analyzed. After assessing the effectiveness of the CB1 receptor antagonist AM251 (3 mg kg(-1), 14 days) on food intake and body weight, we could identified seven key enzymes from either glycolytic pathway or TCA cycle--regulated by both diet and CB1 receptor activity--through comprehensive proteomic approaches involving two-dimensional electrophoresis and MALDI-TOF/LC-ESI trap mass spectrometry. These enzymes were glucose 6-phosphate isomerase (GPI), triosephosphate isomerase (TPI), enolase (Eno3), lactate dehydrogenase (LDHa), glyoxalase-1 (Glo1) and the mitochondrial DLD, whose expressions were modified by AM251 in hypercaloric diet-induced obesity. Specifically, AM251 blocked high-carbohydrate diet (HCD)-induced expression of GPI, TPI, Eno3 and LDHa, suggesting a down-regulation of glucose/pyruvate/lactate pathways under glucose availability. AM251 reversed the HCD-inhibited expression of Glo1 and DLD in the muscle, and the DLD and CB1 receptor expression in the mitochondrial fraction. Interestingly, we identified the presence of CB1 receptors at the membrane of striate muscle mitochondria. DLD over-expression was confirmed in muscle of CB1-/- mice. AM251 increased the pyruvate dehydrogenase and glutathione reductase activity in C2C12 myotubes, and the diaphorase/oxidative activity in the mitochondria fraction. These results indicated an up-regulation of methylglyoxal and TCA cycle activity. Findings suggest that CB1 receptors in muscle modulate glucose/pyruvate/lactate pathways and mitochondrial oxidative activity by targeting DLD.

  6. Therapeutic Effects of Melatonin Receptor Agonists on Sleep and Comorbid Disorders

    Directory of Open Access Journals (Sweden)

    Moshe Laudon

    2014-09-01

    Full Text Available Several melatonin receptors agonists (ramelteon, prolonged-release melatonin, agomelatine and tasimelteon have recently become available for the treatment of insomnia, depression and circadian rhythms sleep-wake disorders. The efficacy and safety profiles of these compounds in the treatment of the indicated disorders are reviewed. Accumulating evidence indicates that sleep-wake disorders and co-existing medical conditions are mutually exacerbating. This understanding has now been incorporated into the new Diagnostic and Statistical Manual of Mental Disorders, 5th Edition (DSM-5. Therefore, when evaluating the risk/benefit ratio of sleep drugs, it is pertinent to also evaluate their effects on wake and comorbid condition. Beneficial effects of melatonin receptor agonists on comorbid neurological, psychiatric, cardiovascular and metabolic symptomatology beyond sleep regulation are also described. The review underlines the beneficial value of enhancing physiological sleep in comorbid conditions.

  7. Glucagon-like peptide receptor agonists and dipeptidyl peptidase-4 inhibitors in the treatment of diabetes

    DEFF Research Database (Denmark)

    Madsbad, Sten; Krarup, Thure; Deacon, Carolyn F;

    2008-01-01

    PURPOSE OF REVIEW: To discuss the virtues and shortcomings of the glucagon-like peptide-1 receptor agonists and the dipeptidyl peptidase-4 inhibitors in the treatment of type 2 diabetes. RECENT FINDINGS: The injectable glucagon-like peptide-1 receptor agonists exenatide significantly improves...... glycaemic control, with average reductions in haemoglobin A1c of about 1.0%, fasting plasma glucose of about 1.4 mmol/l, and causes a weight loss of approximately 2-3 kg after 30 weeks of treatment in patients with type 2 diabetes. The adverse effects are transient nausea and vomiting. The long.......5-1.0%, are weight neutral and without gastrointestinal side-effects. SUMMARY: The benefits and position of the glucagon-like peptide-1 analogues and the dipeptidyl peptidase-4 inhibitors in the diabetes treatment algorithm will be clarified when we have long-term trials with hard cardiovascular endpoints and data...

  8. Trafficking of α1B-adrenergic receptor mediated by inverse agonist in living cells

    Institute of Scientific and Technical Information of China (English)

    MingXU; Ying-huaGUAN; NingXU; Zhang-yiLIANG; Shu-yiWang; YaoSONG; Chi-deHAN; Xin-shengZHAO; You-yiZHANG

    2005-01-01

    AIM The project is aimed at understanding the action of inverse agonist at single molecule level and capturing the real time picture of molecular behavior of α1B-adrenergic receptor (AR) mediated by inverse agonist in living cells by single molecule detection (SMD). METHODS The location and distribution of α1B-AR was detected by laser confocal and whole cell 3H-prazosin binding assay. Dynamic imaging of BODIPY-FL-labeled prazosin (Praz), specific antagonist of (1-AR, was observed in α1B-AR stably expressed human embryonic kidney 293 (HEK293) living cells. The detection of real-time dynamic behaviors of AR was achieved by using fluorescence-labeled AR and its ligand combined with SMD techniques. RESULTS α1B-AR was predominantly distributed on the cell surface and 8.2% of the total receptors were located in cytosol.

  9. Feeding induced by cannabinoids is mediated independently of the melanocortin system.

    Directory of Open Access Journals (Sweden)

    Puspha Sinnayah

    Full Text Available BACKGROUND: Cannabinoids, the active components of marijuana, stimulate appetite, and cannabinoid receptor-1 (CB1-R antagonists suppress appetite and promote weight loss. Little is known about how CB1-R antagonists affect the central neurocircuitry, specifically the melanocortin system that regulates energy balance. METHODOLOGY/PRINCIPAL FINDINGS: Here, we show that peripherally administered CB1-R antagonist (AM251 or agonist equally suppressed or stimulated feeding respectively in A(y , which lack a functional melanocortin system, and wildtype mice, demonstrating that cannabinoid effects on feeding do not require melanocortin circuitry. CB1-R antagonist or agonist administered into the ventral tegmental area (VTA equally suppressed or stimulated feeding respectively, in both genotypes. In addition, peripheral and central cannabinoid administration similarly induced c-Fos activation in brain sites suggesting mediation via motivational dopaminergic circuitry. Amperometry-detected increases in evoked dopamine (DA release by the CB1-R antagonist in nucleus accumbens slices indicates that AM251 modulates DA release from VTA terminals. CONCLUSIONS/SIGNIFICANCE: Our results demonstrate that the effects of cannabinoids on energy balance are independent of hypothalamic melanocortin circuitry and is primarily driven by the reward system.

  10. The liver X receptor agonist T0901317 acts as androgen receptor antagonist in human prostate cancer cells

    International Nuclear Information System (INIS)

    T0901317 is a potent non-steroidal synthetic liver X receptor (LXR) agonist. T0901317 blocked androgenic stimulation of the proliferation of androgen-dependent LNCaP 104-S cells and androgenic suppression of the proliferation of androgen-independent LNCaP 104-R2 cells, inhibited the transcriptional activation of an androgen-dependent reporter gene by androgen, and suppressed gene and protein expression of prostate specific antigen (PSA), a target gene of androgen receptor (AR) without affecting gene and protein expression of AR. T0901317 also inhibited binding of a radiolabeled androgen to AR, but inhibition was much weaker compared to the effect of the antiandrogens, bicalutamide and hydroxyflutamide. The LXR agonist T0901317, therefore, acts as an antiandrogen in human prostate cancer cells

  11. Pharmacophore-directed Homology Modeling and Molecular Dynamics Simulation of G Protein-coupled Receptor: Study of Possible Binding Modes of 5-HT2C Receptor Agonists

    Institute of Scientific and Technical Information of China (English)

    Zhili ZUO; Gang CHEN; Xiaomin LUO; Chummok PUAH; Weiliang ZHU; Kaixian CHEN; Hualiang JIANG

    2007-01-01

    A new pharmacophore-based modeling procedure, including homology modeling, pharmacophore study, flexible molecular docking, and long-time molecular dynamics (MD) simulations, was employed to construct the structure of the human 5-HT2C receptor and determine the characteristics of binding modes of 5-HT2C receptor agonists. An agonist-receptor complex has been constructed based on homology modeling and a pharmacophore hypothesis model based on some high active compounds. Then MD simulations of the ligand-receptor complex in an explicit membrane environment were carried out. The conformation of the 5-HT2C receptor during MD simulation was explored, and the stable binding modes of the studied agonist were determined. Flexible molecular docking of several structurally diverse agonists of the human 5-HT2C receptor was carried out, and the general binding modes of these agonists were investigated. According to the models presented in this work and the results of Flexi-Dock, the involvement of the amino acid residues Asp134,Ser138, Asn210, Asn331, Tyr358, Ile131, Ser 132, Val135, Thr139, Ile189, Va1202, Va1208, Leu209, Phe214,Va1215, Gly218, Ser219, Phe223, Trp324, Phe327, and Phe328 in agonist recognition was studied. The obtained binding modes of the human 5-HT2C receptor agonists have good agreement with the site-directed mutagenesis data and other studies.

  12. Liver X Receptor Agonists Inhibit the Phospholipid Regulatory Gene CTP: Phosphoethanolamine Cytidylyltransferase-Pcyt2

    OpenAIRE

    Lin Zhu; Marica Bakovic

    2008-01-01

    Metabolic pulse-chase experiments demonstrated that 25-hydroxycholesterol (25-OH), the endogenous activator of the liver X receptor (LXR), significantly reduced the biosynthesis of phosphatidylethanolamine via CDP-ethanolamine (Kennedy) pathway at the step catalyzed by CTP: phosphoethanolamine cytidylyltransferase (Pcyt2). In the mouse embryonic fibroblasts C3H10T1/2, the LXR synthetic agonist TO901317 lowered Pcyt2 promoter-luciferase activity in a concentration-dependent manner. Furthermore...

  13. Novel heterocyclic scaffolds of GW4064 as farnesoid X receptor agonists.

    Science.gov (United States)

    Smalley, Terrence L; Boggs, Sharon; Caravella, Justin A; Chen, Lihong; Creech, Katrina L; Deaton, David N; Kaldor, Istvan; Parks, Derek J

    2015-01-15

    The farnesoid X receptor (FXR) may play a crucial role in a number of metabolic diseases and, as such, could potentially serve as a target for the development of therapeutics as a treatment for those diseases. Previous work has described GW4064 as an FXR agonist with an interesting activity profile. This manuscript will describe the synthesis of novel analogs of GW4064 and the activity profile of those analogs. PMID:25499883

  14. Preventing or attenuating amphotericin B nephrotoxicity with dopamine receptor agonists: a literature review

    OpenAIRE

    Iman Karimzadeh; Hossein Khalili; Mohammad Mahdi Sagheb

    2016-01-01

    Nephrotoxicity is generally considered as the most clinically significant and dose-limiting adverse reaction of amphotericin B. Currently, only the clinical effectiveness of salt loading and administering lipid formulations of amphotericin B have been clearly demonstrated to prevent its nephrotoxicity. In this review, we collected the published data related to dopamine receptor agonists in preventing amphotericin B nephrotoxicity. A literature search was conducted by the relevant keywords lik...

  15. Effects of dopamine D2-like receptor agonists in mice trained to discriminate cocaine from saline: influence of feeding condition

    Science.gov (United States)

    Collins, Gregory T.; Jackson, Jonathan A.; Koek, Wouter; France, Charles P.

    2014-01-01

    In rats, the discriminative stimulus effects of direct- and indirect-acting dopamine receptor agonists are mediated by multiple dopamine receptor subtypes and the relative contribution of dopamine D2 and D3 receptors to these effects varies as a function of feeding condition. In these studies, free-fed and food-restricted mice were trained to discriminate 10.0 mg/kg cocaine using a two-lever discrimination procedure in which responding was maintained by food. Both groups of mice acquired the discrimination; however, free-fed mice responded at lower rates than food-restricted mice. Dopamine D3 receptor agonists, pramipexole and quinpirole, increased cocaine-appropriate responding (>85%) in food-restricted, but not in free-fed mice. The dopamine D2 receptor agonist, sumanirole, and the nonselective dopamine receptor agonist, apomorphine, failed to increase cocaine-appropriate responding in either group. Free-fed mice were more sensitive than food-restricted mice to the rate-decreasing effects of dopamine receptor agonists and these effects could not be overcome by increasing the magnitude of reinforcement. Because feeding condition did not alter quinpirole-induced hypothermia, it is unlikely that differences in the discriminative stimulus or rate-decreasing effects of dopamine D2-like receptor agonists were due to differences in the pharmacokinetic properties of the drugs. Although these results suggest that the discriminative stimulus effects of cocaine are mediated by both dopamine D2 and D3 receptors in food-restricted mice, the increased sensitivity of free-fed mice to the rate-decreasing effects of dopamine D2-like receptor agonists limited conclusions about the impact of feeding conditions on the relative contribution of dopamine D2 and D3 receptors to the discriminative stimulus effects of cocaine. PMID:24561049

  16. Radiosynthesis and evaluation of 11C-CIMBI-5 as a 5-HT2A receptor agonist radioligand for PET

    DEFF Research Database (Denmark)

    Ettrup, Anders; Palner, Mikael; Gillings, Nicolas;

    2010-01-01

    PET tracers would, however, enable imaging of the active, high-affinity state of receptors, which may provide a more meaningful assessment of membrane-bound receptors. In this study, we radiolabel the high-affinity 5-HT(2A) receptor agonist 2-(4-iodo-2,5-dimethoxyphenyl)-N-(2-[(11)C-OCH(3...

  17. The role of Arg(78) in the metabotropic glutamate receptor mGlu(1) for agonist binding and selectivity

    DEFF Research Database (Denmark)

    Jensen, Anders A.; Sheppard, P O; O'Hara, P J;

    2000-01-01

    The metabotropic glutamate receptors belong to family C of the G-protein coupled receptor superfamily. These receptors all possess large extracellular amino terminal domains, where agonist binding takes place. We have previously constructed a molecular model of the amino terminal domain of the mG...

  18. Selective Human Estrogen Receptor Partial Agonists (ShERPAs) for Tamoxifen-Resistant Breast Cancer.

    Science.gov (United States)

    Xiong, Rui; Patel, Hitisha K; Gutgesell, Lauren M; Zhao, Jiong; Delgado-Rivera, Loruhama; Pham, Thao N D; Zhao, Huiping; Carlson, Kathryn; Martin, Teresa; Katzenellenbogen, John A; Moore, Terry W; Tonetti, Debra A; Thatcher, Gregory R J

    2016-01-14

    Almost 70% of breast cancers are estrogen receptor α (ERα) positive. Tamoxifen, a selective estrogen receptor modulator (SERM), represents the standard of care for many patients; however, 30-50% develop resistance, underlining the need for alternative therapeutics. Paradoxically, agonists at ERα such as estradiol (E2) have demonstrated clinical efficacy in patients with heavily treated breast cancer, although side effects in gynecological tissues are unacceptable. A drug that selectively mimics the actions of E2 in breast cancer therapy but minimizes estrogenic effects in other tissues is a novel, therapeutic alternative. We hypothesized that a selective human estrogen receptor partial agonist (ShERPA) at ERα would provide such an agent. Novel benzothiophene derivatives with nanomolar potency in breast cancer cell cultures were designed. Several showed partial agonist activity, with potency of 0.8-76 nM, mimicking E2 in inhibiting growth of tamoxifen-resistant breast cancer cell lines. Three ShERPAs were tested and validated in xenograft models of endocrine-independent and tamoxifen-resistant breast cancer, and in contrast to E2, ShERPAs did not cause significant uterine growth.

  19. Selective Human Estrogen Receptor Partial Agonists (ShERPAs) for Tamoxifen-Resistant Breast Cancer.

    Science.gov (United States)

    Xiong, Rui; Patel, Hitisha K; Gutgesell, Lauren M; Zhao, Jiong; Delgado-Rivera, Loruhama; Pham, Thao N D; Zhao, Huiping; Carlson, Kathryn; Martin, Teresa; Katzenellenbogen, John A; Moore, Terry W; Tonetti, Debra A; Thatcher, Gregory R J

    2016-01-14

    Almost 70% of breast cancers are estrogen receptor α (ERα) positive. Tamoxifen, a selective estrogen receptor modulator (SERM), represents the standard of care for many patients; however, 30-50% develop resistance, underlining the need for alternative therapeutics. Paradoxically, agonists at ERα such as estradiol (E2) have demonstrated clinical efficacy in patients with heavily treated breast cancer, although side effects in gynecological tissues are unacceptable. A drug that selectively mimics the actions of E2 in breast cancer therapy but minimizes estrogenic effects in other tissues is a novel, therapeutic alternative. We hypothesized that a selective human estrogen receptor partial agonist (ShERPA) at ERα would provide such an agent. Novel benzothiophene derivatives with nanomolar potency in breast cancer cell cultures were designed. Several showed partial agonist activity, with potency of 0.8-76 nM, mimicking E2 in inhibiting growth of tamoxifen-resistant breast cancer cell lines. Three ShERPAs were tested and validated in xenograft models of endocrine-independent and tamoxifen-resistant breast cancer, and in contrast to E2, ShERPAs did not cause significant uterine growth. PMID:26681208

  20. The identification of GPR3 inverse agonist AF64394; the first small molecule inhibitor of GPR3 receptor function.

    Science.gov (United States)

    Jensen, Thomas; Elster, Lisbeth; Nielsen, Søren Møller; Poda, Suresh Babu; Loechel, Frosty; Volbracht, Christiane; Klewe, Ib Vestergaard; David, Laurent; Watson, Stephen P

    2014-11-15

    The identification of the novel and selective GPR3 inverse agonist AF64394, the first small molecule inhibitor of GPR3 receptor function, is described. Structure activity relationships and syntheses based around AF64394 are reported.

  1. Conversion of agonist site to metal-ion chelator site in the β2-adrenergic receptor

    OpenAIRE

    Elling, Christian E.; Thirstrup, Kenneth; Holst, Birgitte; Thue W. Schwartz

    1999-01-01

    Previously metal-ion sites have been used as structural and functional probes in seven transmembrane receptors (7TM), but as yet all the engineered sites have been inactivating. Based on presumed agonist interaction points in transmembrane III (TM-III) and -VII of the β2-adrenergic receptor, in this paper we construct an activating metal-ion site between the amine-binding Asp-113 in TM-III—or a His residue introduced at this position—and a Cys residue substituted for Asn-312 in TM-VII. No inc...

  2. Chronic Administration of 5-HT1A Receptor Agonist Relieves Depression and Depression-Induced Hypoalgesia

    OpenAIRE

    Zhao-Cai Jiang; Wei-Jing Qi; Jin-Yan Wang; Fei Luo

    2014-01-01

    Previous studies have shown that depressed patients as well as animal models of depression exhibit decreased sensitivity to evoked pain stimuli, and serotonin is indicated to be involved in depression-induced hypoalgesia. The purpose of this study was to investigate the potential role of 5-HT1A receptor in the depression-induced hypoalgesia. Acute or chronic administration of 5-HT1A receptor agonist, 8-OH-DPAT, was performed in olfactory bulbectomy (OB) and sham-operated rats. The depression-...

  3. A Cannabinoid CB1 Receptor-Positive Allosteric Modulator Reduces Neuropathic Pain in the Mouse with No Psychoactive Effects.

    Science.gov (United States)

    Ignatowska-Jankowska, Bogna M; Baillie, Gemma L; Kinsey, Steven; Crowe, Molly; Ghosh, Sudeshna; Owens, Robert A; Damaj, Imad M; Poklis, Justin; Wiley, Jenny L; Zanda, Matteo; Zanato, Chiara; Greig, Iain R; Lichtman, Aron H; Ross, Ruth A

    2015-12-01

    The CB1 receptor represents a promising target for the treatment of several disorders including pain-related disease states. However, therapeutic applications of Δ(9)-tetrahydrocannabinol and other CB1 orthosteric receptor agonists remain limited because of psychoactive side effects. Positive allosteric modulators (PAMs) offer an alternative approach to enhance CB1 receptor function for therapeutic gain with the promise of reduced side effects. Here we describe the development of the novel synthetic CB1 PAM, 6-methyl-3-(2-nitro-1-(thiophen-2-yl)ethyl)-2-phenyl-1H-indole (ZCZ011), which augments the in vitro and in vivo pharmacological actions of the CB1 orthosteric agonists CP55,940 and N-arachidonoylethanolamine (AEA). ZCZ011 potentiated binding of [(3)H]CP55,940 to the CB1 receptor as well as enhancing AEA-stimulated [(35)S]GTPγS binding in mouse brain membranes and β-arrestin recruitment and ERK phosphorylation in hCB1 cells. In the whole animal, ZCZ011 is brain penetrant, increased the potency of these orthosteric agonists in mouse behavioral assays indicative of cannabimimetic activity, including antinociception, hypothermia, catalepsy, locomotor activity, and in the drug discrimination paradigm. Administration of ZCZ011 alone was devoid of activity in these assays and did not produce a conditioned place preference or aversion, but elicited CB1 receptor-mediated antinociceptive effects in the chronic constriction nerve injury model of neuropathic pain and carrageenan model of inflammatory pain. These data suggest that ZCZ011 acts as a CB1 PAM and provide the first proof of principle that CB1 PAMs offer a promising strategy to treat neuropathic and inflammatory pain with minimal or no cannabimimetic side effects.

  4. Estrogen Receptor β Agonists Differentially Affect the Growth of Human Melanoma Cell Lines.

    Directory of Open Access Journals (Sweden)

    Monica Marzagalli

    Full Text Available Cutaneous melanoma is an aggressive malignancy; its incidence is increasing worldwide and its prognosis remains poor. Clinical observations indicate that estrogen receptor β (ERβ is expressed in melanoma tissues and its expression decreases with tumor progression, suggesting its tumor suppressive function. These experiments were performed to investigate the effects of ERβ activation on melanoma cell growth.Protein expression was analyzed by Western blot and immunofluorescence assays. Cell proliferation was assessed by counting the cells by hemocytometer. ERβ transcriptional activity was evaluated by gene reporter assay. Global DNA methylation was analyzed by restriction enzyme assay and ERβ isoforms were identified by qRT-PCR. We demonstrated that ERβ is expressed in a panel of human melanoma cell lines (BLM, WM115, A375, WM1552. In BLM (NRAS-mutant cells, ERβ agonists significantly and specifically inhibited cell proliferation. ERβ activation triggered its cytoplasmic-to-nuclear translocation and transcriptional activity. Moreover, the antiproliferative activity of ERβ agonists was associated with an altered expression of G1-S transition-related proteins. In these cells, global DNA was found to be hypomethylated when compared to normal melanocytes; this DNA hypomethylation status was reverted by ERβ activation. ERβ agonists also decreased the proliferation of WM115 (BRAF V600D-mutant cells, while they failed to reduce the growth of A375 and WM1552 (BRAF V600E-mutant cells. Finally, we could observe that ERβ isoforms are expressed at different levels in the various cell lines. Specific oncogenic mutations or differential expression of receptor isoforms might be responsible for the different responses of cell lines to ERβ agonists.Our results demonstrate that ERβ is expressed in melanoma cell lines and that ERβ agonists differentially regulate the proliferation of these cells. These data confirm the notion that melanoma is a

  5. A Selective V1A Receptor Agonist, Selepressin, Is Superior to Arginine Vasopressin and to Norepinephrine in Ovine Septic Shock*

    OpenAIRE

    He, Xinrong; Su, Fuhong; Taccone, Fabio Silvio; Laporte, Régent; Kjølbye, Anne Louise; Zhang, Jing; Xie, Keliang; Moussa, Mouhamed Djahoum; Reinheimer, Torsten Michael; Vincent, Jean-Louis

    2015-01-01

    Objective: Selective vasopressin V1A receptor agonists may have advantages over arginine vasopressin in the treatment of septic shock. We compared the effects of selepressin, a selective V1A receptor agonist, arginine vasopressin, and norepinephrine on hemodynamics, organ function, and survival in an ovine septic shock model. Design: Randomized animal study. Setting: University hospital animal research laboratory. Subjects: Forty-six adult female sheep. Interventions: Fecal peritonitis was in...

  6. Anamorelin HCl (ONO-7643), a novel ghrelin receptor agonist, for the treatment of cancer anorexia-cachexia syndrome: preclinical profile

    OpenAIRE

    Pietra, Claudio; Takeda, Yasuhiro; Tazawa-Ogata, Naoko; Minami, Masashi; Yuanfeng, Xia; Duus, Elizabeth Manning; Northrup, Robert

    2014-01-01

    Background Anamorelin HCl (ANAM) is a novel, orally active, ghrelin receptor agonist in clinical development for the treatment of cancer cachexia. We report in vitro and in vivo studies evaluating the preclinical pharmacologic profile of ANAM. Methods Fluorescent imaging plate reader and binding assays in HEK293 and baby hamster kidney cells determined the agonist and antagonist activity of ANAM, and its affinity for the ghrelin receptor. Rat pituitary cells were incubated with ANAM to evalua...

  7. Development of a homogeneous calcium mobilization assay for high throughput screening of mas-related gene receptor agonists

    Institute of Scientific and Technical Information of China (English)

    Rui ZHANG; Pang-ke YAN; Cai-hong ZHOU; Jia-yu LIAO; Ming-wei WANG

    2007-01-01

    Aim: To develop homogeneous calcium mobilization assay for high-throughput screening (HTS) of mas-related gene (Mrg) receptor agonists. Methods: CHO-K1 cells stably expressing the full-length MrgD receptor and a calcium-sensitive dye were used to develop an HTS assay based on intracellular calcium influx. This method was applied to large-scale screening of a library containing 8000 synthetic compounds and natural product extracts, cAMP measurements were camed out to verify the bioactivities of the hits found by the calcium mobilization assay. Similar approaches were also employed in the identification of the MrgA1 recep-tor agonists following HTS of 16 000 samples. Results: EC50 values of the positive control compounds (β-alanine for MrgD receptor and dynorphin A for MrgA1 receptor) determined by the calcium mobilization assay were consistent with those reported in the literature, and the Z' factors were 0.65 and 0.50 for MrgD and MrgA1 receptor assay, respectively. About 31 compounds for the MrgD receptor and 48 compounds for the MrgA1 receptor showing ≥20% of the maximal agonist activities found in the controls were initially identified as hits. Secondary screen- ing confirmed that 2 compounds for each receptor possessed specific agonist activities. Intracellular cAMP level measurements indicated that the 2 confirmed hits displayed the functionality of the MrgD receptor agonists. Conclusion: A series of validation studies demonstrated that the homogeneous calcium mobili-zation assay developed was highly efficient, amenable to automation and a robust tool to screen potential MrgD and MrgA1 receptor agonists. Its application may be expanded to other G-protein coupled receptors that mobilize calcium influx upon activation.

  8. Comparative receptor surface analysis of agonists for tyramine receptor which inhibit sex-pheromone production in Plodia interpunctella.

    Science.gov (United States)

    Hirashima, A; Eiraku, T; Kuwano, E; Eto, M

    2004-03-01

    The quantitative structure-activity relationship (QSAR) of a set of 29 agonists for tyramine (TA) receptor responsible for the inhibition of sex-pheromone production in Plodia interpunctella, was analyzed using comparative receptor surface analysis (CoRSA). Using the common steric and electrostatic features of the most active members of a series of compounds, CoRSA generated a virtual receptor model, represented as points on a surface complementary to the van der Waals or Wyvill steric surface of the aligned compounds. Three-dimensional energetics descriptors were calculated from receptor surface model (RSM)/ligand interaction and these three-dimensional descriptors were used in genetic partial least squares data analysis to generate a QSAR model, giving a 3D QSAR with r(2)=0.969 for calibration and CV- r(2)=0.635 for the leave-one-out cross validation.

  9. Collybolide is a novel biased agonist of κ-opioid receptors with potent antipruritic activity.

    Science.gov (United States)

    Gupta, Achla; Gomes, Ivone; Bobeck, Erin N; Fakira, Amanda K; Massaro, Nicholas P; Sharma, Indrajeet; Cavé, Adrien; Hamm, Heidi E; Parello, Joseph; Devi, Lakshmi A

    2016-05-24

    Among the opioid receptors, the κ-opioid receptor (κOR) has been gaining considerable attention as a potential therapeutic target for the treatment of complex CNS disorders including depression, visceral pain, and cocaine addiction. With an interest in discovering novel ligands targeting κOR, we searched natural products for unusual scaffolds and identified collybolide (Colly), a nonnitrogenous sesquiterpene from the mushroom Collybia maculata. This compound has a furyl-δ-lactone core similar to that of Salvinorin A (Sal A), another natural product from the plant Salvia divinorum Characterization of the molecular pharmacological properties reveals that Colly, like Sal A, is a highly potent and selective κOR agonist. However, the two compounds differ in certain signaling and behavioral properties. Colly exhibits 10- to 50-fold higher potency in activating the mitogen-activated protein kinase pathway compared with Sal A. Taken with the fact that the two compounds are equipotent for inhibiting adenylyl cyclase activity, these results suggest that Colly behaves as a biased agonist of κOR. Behavioral studies also support the biased agonistic activity of Colly in that it exhibits ∼10-fold higher potency in blocking non-histamine-mediated itch compared with Sal A, and this difference is not seen in pain attenuation by these two compounds. These results represent a rare example of functional selectivity by two natural products that act on the same receptor. The biased agonistic activity, along with an easily modifiable structure compared with Sal A, makes Colly an ideal candidate for the development of novel therapeutics targeting κOR with reduced side effects. PMID:27162327

  10. Nigramide J is a novel potent inverse agonist of the human constitutive androstane receptor.

    Science.gov (United States)

    Kanno, Yuichiro; Tanuma, Nobuaki; Yatsu, Tomofumi; Li, Wei; Koike, Kazuo; Inouye, Yoshio

    2014-02-01

    The constitutive androstane receptor (CAR, NR1I3) is very important for drug development and for understanding pharmacokinetic drug-drug interactions. We screened by mammalian one hybrid assay among natural compounds to discover novel ligands of human constitutive androstane receptor (hCAR). hCAR transcriptional activity was measured by luciferase assay and mRNA levels of CYP2B6 and CYP3A4 in HepTR-hCAR cells and human primary hepatocytes were measured by real-time RT-PCR. Nigramide J (NJ) whose efficacy is comparable to those of hitherto known inverse agonists such as clotrimazole, PK11195, and ethinylestradiol. NJ is a naturally occurring cyclohexane-type amide alkaloid that was isolated from the roots of Piper nigrum. The suppressive effect of NJ on the CAR-dependent transcriptional activity was found to be species specific, in the descending order of hCAR, rat CAR, and mouse CAR. The unliganded hCAR-dependent transactivation of reporter and endogenous genes was suppressed by NJ at concentrations higher than 5 μmol/L. The ligand-binding cavity of hCAR was shared by NJ and CITCO, because they were competitive in the binding to hCAR. NJ interfered with the interaction of hCAR with coactivator SRC-1, but not with its interaction with the corepressor NCoR1. Furthermore, NJ is agonist of human pregnane X receptor (hPXR). NJ is a dual ligand of hCAR and hPXR, being an agonist of hPXR and an inverse agonist of hCAR. PMID:25505573

  11. Agonist action of taurine on glycine receptors in rat supraoptic magnocellular neurones: possible role in osmoregulation.

    Science.gov (United States)

    Hussy, N; Deleuze, C; Pantaloni, A; Desarménien, M G; Moos, F

    1997-08-01

    1. To evaluate the implication of taurine in the physiology of supraoptic neurones, we (i) investigated the agonist properties of taurine on glycine and GABAA receptors of supraoptic magnocellular neurones acutely dissociated from adult rats, using whole-cell voltage clamp, (ii) studied the effects of taurine and strychnine in vivo by extracellular recordings of supraoptic vasopressin neurones in anaesthetized rats, and (iii) measured the osmolarity-dependent release of endogenous taurine from isolated supraoptic nuclei by HPLC. 2. GABA, glycine and taurine evoked rapidly activating currents that all reversed close to the equilibrium potential for Cl-, indicating activation of Cl(-)-selective channels. Glycine-activated currents were reversibly blocked by strychnine (IC50 of 35 nM with 100 microM glycine), but were unaffected by the GABAA antagonist gabazine (1-3 microM). GABA-activated currents were reversibly antagonized by 3 microM gabazine, but not by strychnine (up to 1 microM). 3. Responses to 1 mM taurine were blocked by strychnine but not by gabazine and showed no additivity with glycine-induced currents, indicating selective activation of glycine receptors. Responses to 10 mM taurine were partially antagonized by gabazine, the residual current being blocked by strychnine. Thus, taurine is also a weak agonist of GABAA receptors. 4. In the presence of gabazine, taurine activated glycine receptors with an EC50 of 406 microM. Taurine activated at most 70% of maximal glycine currents, suggesting that it is a partial agonist of glycine receptors. 5. In vivo, locally applied strychnine (300 nM) increased and taurine (1 mM) decreased the basal electrical activity of vasopressin neurones in normally hydrated rats. The effect of strychnine was markedly more pronounced in water-loaded rats. 6. Taurine, which is concentrated in supraoptic glial cells, could be released from isolated supraoptic nuclei upon hyposmotic stimulation. Decreases in osmolarity of 15 and 30

  12. Therapeutic potential of vanilloid receptor TRPV1 agonists and antagonists as analgesics: Recent advances and setbacks.

    Science.gov (United States)

    Wong, Gilbert Y; Gavva, Narender R

    2009-04-01

    The vanilloid receptor TRPV1 is a homotetrameric, non-selective cation channel abundantly expressed in the nociceptors (c-fibers). TRPV1 is considered as a highly validated pain target because, i) its agonists such as capsaicin cause desensitization of TRPV1 channels that relieves pain behaviors in preclinical species, and ii) its antagonists relieve pain behaviors in rodent models of inflammation, osteoarthritis, and cancer. Hence, both agonists and antagonists of TRPV1 are being evaluated as potential analgesics in clinical trials. Clinical trial results of TRPV1 agonists such as resiniferatoxin in interstitial cystitis, NGX 4010 in post-herpetic neuralgia, and 4975 (Adlea) in osteoarthritis, bunionectomy, and Morton's neuroma have been reported. Similarly, clinical trial results of TRPV1 antagonists such as SB-705498 and AMG 517 have also been published recently. Overall, some molecules (e.g., capsaicin) demonstrated potential analgesia in certain conditions (postsurgical pain, postherpetic neuralgia, pain in diabetic neuropathy, osteoarthritis, bunionectomy, and Morton's neuroma), whereas others fell out of the clinic due to on-target liabilities or failed to demonstrate efficacy. This review summarizes recent advances and setbacks of TRPV1 agonists and antagonists in the clinic and predicts future directions. PMID:19150372

  13. Divergent teratogenicity of agonists of retinoid X receptors in embryos of zebrafish (Danio rerio).

    Science.gov (United States)

    Shi, Huahong; Zhu, Pan; Sun, Zhi; Yang, Bo; Zheng, Liang

    2012-07-01

    Zebrafish (Danio rerio) embryos were comparably exposed to seven known agonists of retinoid X receptors (RXRs) including two endogenous compounds (9-cis-retinoic acid and docosahexaenoic acid), four man-made selective ligands (LGD1069, SR11237, fluorobexarotene and CD3254), and a biocide (triphenyltin). The dominant phenotypes of malformation were sharp mouths and small caudal fins in 1 mg/L SR11237-treated group after 5 days exposure. 9-cis-retinoic acid and LGD1069 induced multiple malformations including small eyes, bent notochords, reduced brain, enlarged proctodaems, absence of fins, short tails and edema after 5 days exposure. Fluorobexarotene and CD3254 induced similar phenotypes of malformations after 5 days exposure at low concentration (20 μg/L) to those after the 1st d exposure at high concentrations (50 and 100 μg/L). Triphenlytin induced multiple malformations including deformed eyes, bent notochords, bent tails, and edema in hearts after 5 days exposure at concentrations of 1-10 μg Sn/L. In contrast, no discernible malformations were observed in triphenlytin-treated groups after each separate day exposure. These agonists not only showed different ability of teratogenicity but also induced different phenotypes of malformation in zebrafish embryos. In addition, the sensitive stages of zebrafish embryos were different in response to these agonists. Therefore, our results suggest that the agonists of RXRs had divergent teratogenicity in zebrafish embryos. PMID:22526925

  14. Melanocortin 1 receptor agonist protects podocytes through catalase and RhoA activation.

    Science.gov (United States)

    Elvin, Johannes; Buvall, Lisa; Lindskog Jonsson, Annika; Granqvist, Anna; Lassén, Emelie; Bergwall, Lovisa; Nyström, Jenny; Haraldsson, Börje

    2016-05-01

    Drugs containing adrenocorticotropic hormone have been used as therapy for patients with nephrotic syndrome. We have previously shown that adrenocorticotropic hormone and a selective agonist for the melanocortin 1 receptor (MC1R) exert beneficial actions in experimental membranous nephropathy with reduced proteinuria, reduced oxidative stress, and improved glomerular morphology and function. Our hypothesis is that MC1R activation in podocytes elicits beneficial effects by promoting stress fibers and maintaining podocyte viability. To test the hypothesis, we cultured podocytes and used highly specific agonists for MC1R. Podocytes were subjected to the nephrotic-inducing agent puromycin aminonucleoside, and downstream effects of MC1R activation on podocyte survival, antioxidant defense, and cytoskeleton dynamics were studied. To increase the response and enhance intracellular signals, podocytes were transduced to overexpress MC1R. We showed that puromycin promotes MC1R expression in podocytes and that activation of MC1R promotes an increase of catalase activity and reduces oxidative stress, which results in the dephosphorylation of p190RhoGAP and formation of stress fibers through RhoA. In addition, MC1R agonists protect against apoptosis. Together, these mechanisms protect the podocyte against puromycin. Our findings strongly support the hypothesis that selective MC1R-activating agonists protect podocytes and may therefore be useful to treat patients with nephrotic syndromes commonly considered as podocytopathies. PMID:26887829

  15. Identification of higenamine in Radix Aconiti Lateralis Preparata as a beta2-adrenergic receptor agonist

    Institute of Scientific and Technical Information of China (English)

    Gang BAI; Yang YANG; Qian SHI; Ze LIU; Qi ZHANG; Yuan-yuan ZHU

    2008-01-01

    Aim:To screen beta2-adrenergic receptor (β+-AR) agonists from Radix Aconiti Lateralis Preparata (RALP) as potential drug leads for asthma using a sensi-tive cell-based agonist assay.Methods:The β+-AR gene was stably expressed by Chinese hamster ovary (CHO) cells also stably expressing a cyclic adenosine monophosphate (AMP) response element-linked enhanced green fluorescent pro-tein reporter gene.The cells were used to screen agonists from high-performance liquid chromatographic fractions of an extract of RALE The fraction with the highest activity was selected for further compound isolation and the study of the structure-activity relationship.Its active compound was further identified by chromatography and mass spectrometry.Results:Bioactivity-directed fraction-ation of the crude extract of RALP led to the isolation and characterization of the effective compound,namely hignamine.It could dose-dependently relax the iso-lated guinea pig trachea strip precontraction with acetylcholine with EC50 value of (2.60±0.36)x 10-5 mol/L.Further in vivo studies also displayed that higuamine could protect experimental asthma model induced by histamine in guinea pigs to prolong the latent periods of asthma.Conclusion:Hignamine,as a β2-AR ago-nist existing in the extract of RALE is the key compound contributing to the suc-cessful relief of the bronchoconstriction.

  16. Hydroxytyrosol Inhibits Cannabinoid CB1 Receptor Gene Expression in 3T3-L1 Preadipocyte Cell Line.

    Science.gov (United States)

    Tutino, Valeria; Orlando, Antonella; Russo, Francesco; Notarnicola, Maria

    2016-02-01

    The 3T3-L1 preadipocyte cell line is a well characterized cell model for studying the adipocyte status and the molecular mechanisms involved in differentiation of these cells. 3T3-L1 preadipocytes have the ability to synthesize and degrade endocannabinoid anandamide (AEA) and their differentiation into adipocytes increases the expression of cannabinoid (CB1) and PPAR-γ receptors. Clinically, the blocking stimulation of the endocannabinoid pathway has been one of the first approaches proposed to counteract the obesity and obesity-associated diseases (such as diabetes, metabolic syndrome and cancer). In this connection, here we studied in cultured 3T3-L1 pre-adipocytes the effects of n-3-PUFA, α-Linolenic acid (OM-3), n-6-PUFA, Linoleic acid (OM-6), and hydroxytyrosol (HT) on the expression of CB1 receptor gene and the adipogenesis-related genes PPAR-γ, Fatty Acid Synthase (FAS) and Lipoprotein Lipase (LPL). HT was able to inhibit 3T3-L1 cell differentiation by down-regulating cell proliferation and CB1 receptor gene expression. HT exhibited anti-adipogenic effects, whereas OM-3 and OM-6 exerted an inhibitory action on cell proliferation associated with an induction of the preadipocytes differentiation and CB1 receptor gene expression. Moreover, the expression of FAS and LPL genes resulted increased after treatment with both HT and OM-3 and OM-6. The present study points out that the intake of molecules such as HT, contained in extra virgin olive oil, may be considered also in view of antiobesity and antineoplastic properties by acting directly on the adipose tissue and modulating CB1 receptor gene transcription.

  17. Cannabinoid type 1 (CB1) receptors on Sim1-expressing neurons regulate energy expenditure in male mice.

    Science.gov (United States)

    Cardinal, Pierre; Bellocchio, Luigi; Guzmán-Quevedo, Omar; André, Caroline; Clark, Samantha; Elie, Melissa; Leste-Lasserre, Thierry; Gonzales, Delphine; Cannich, Astrid; Marsicano, Giovanni; Cota, Daniela

    2015-02-01

    The paraventricular nucleus of the hypothalamus (PVN) regulates energy balance by modulating not only food intake, but also energy expenditure (EE) and brown adipose tissue thermogenesis. To test the hypothesis that cannabinoid type 1 (CB1) receptor in PVN neurons might control these processes, we used the Cre/loxP system to delete CB1 from single-minded 1 (Sim1) neurons, which account for the majority of PVN neurons. On standard chow, mice lacking CB1 receptor in Sim1 neurons (Sim1-CB1-knockout [KO]) had food intake, body weight, adiposity, glucose metabolism, and EE comparable with wild-type (WT) (Sim1-CB1-WT) littermates. However, maintenance on a high-fat diet revealed a gene-by-diet interaction whereby Sim1-CB1-KO mice had decreased adiposity, improved insulin sensitivity, and increased EE, whereas feeding behavior was similar to Sim1-CB1-WT mice. Additionally, high-fat diet-fed Sim1-CB1-KO mice had increased mRNA expression of the β3-adrenergic receptor, as well as of uncoupling protein-1, cytochrome-c oxidase subunit IV and mitochondrial transcription factor A in the brown adipose tissue, all molecular changes suggestive of increased thermogenesis. Pharmacological studies using β-blockers suggested that modulation of β-adrenergic transmission play an important role in determining EE changes observed in Sim1-CB1-KO. Finally, chemical sympathectomy abolished the obesity-resistant phenotype of Sim1-CB1-KO mice. Altogether, these findings reveal a diet-dependent dissociation in the CB1 receptor control of food intake and EE, likely mediated by the PVN, where CB1 receptors on Sim1-positive neurons do not impact food intake but hinder EE during dietary environmental challenges that promote body weight gain.

  18. Striatal but not frontal cortical up-regulation of the epidermal growth factor receptor in rats exposed to immune activation in utero and cannabinoid treatment in adolescence.

    Science.gov (United States)

    Idrizi, Rejhan; Malcolm, Peter; Weickert, Cynthia Shannon; Zavitsanou, Katerina; Suresh Sundram

    2016-06-30

    In utero maternal immune activation (MIA) and cannabinoid exposure during adolescence constitute environmental risk factors for schizophrenia. We investigated these risk factors alone and in combination ("two-hit") on epidermal growth factor receptor (EGFR) and neuregulin-1 receptor (ErbB4) levels in the rat brain. EGFR but not ErbB4 receptor protein levels were significantly increased in the nucleus accumbens and striatum of "two-hit" rats only, with no changes seen at the mRNA level. These findings support region specific EGF-system dysregulation as a plausible mechanism in this animal model of schizophrenia pathogenesis. PMID:27138815

  19. Quantitative phosphoproteomics unravels biased phosphorylation of serotonin 2A receptor at Ser280 by hallucinogenic versus nonhallucinogenic agonists.

    Science.gov (United States)

    Karaki, Samah; Becamel, Carine; Murat, Samy; Mannoury la Cour, Clotilde; Millan, Mark J; Prézeau, Laurent; Bockaert, Joël; Marin, Philippe; Vandermoere, Franck

    2014-05-01

    The serotonin 5-HT(2A) receptor is a primary target of psychedelic hallucinogens such as lysergic acid diethylamine, mescaline, and psilocybin, which reproduce some of the core symptoms of schizophrenia. An incompletely resolved paradox is that only some 5-HT(2A) receptor agonists exhibit hallucinogenic activity, whereas structurally related agonists with comparable affinity and activity lack such a psychoactive activity. Using a strategy combining stable isotope labeling by amino acids in cell culture with enrichment in phosphorylated peptides by means of hydrophilic interaction liquid chromatography followed by immobilized metal affinity chromatography, we compared the phosphoproteome in HEK-293 cells transiently expressing the 5-HT(2A) receptor and exposed to either vehicle or the synthetic hallucinogen 1-[2,5-dimethoxy-4-iodophenyl]-2-aminopropane (DOI) or the nonhallucinogenic 5-HT(2A) agonist lisuride. Among the 5995 identified phosphorylated peptides, 16 sites were differentially phosphorylated upon exposure of cells to DOI versus lisuride. These include a serine (Ser(280)) located in the third intracellular loop of the 5-HT(2A) receptor, a region important for its desensitization. The specific phosphorylation of Ser(280) by hallucinogens was further validated by quantitative mass spectrometry analysis of immunopurified receptor digests and by Western blotting using a phosphosite specific antibody. The administration of DOI, but not of lisuride, to mice, enhanced the phosphorylation of 5-HT(2A) receptors at Ser(280) in the prefrontal cortex. Moreover, hallucinogens induced a less pronounced desensitization of receptor-operated signaling in HEK-293 cells and neurons than did nonhallucinogenic agonists. The mutation of Ser(280) to aspartic acid (to mimic phosphorylation) reduced receptor desensitization by nonhallucinogenic agonists, whereas its mutation to alanine increased the ability of hallucinogens to desensitize the receptor. This study reveals a biased

  20. Quantitative Phosphoproteomics Unravels Biased Phosphorylation of Serotonin 2A Receptor at Ser280 by Hallucinogenic versus Nonhallucinogenic Agonists*

    Science.gov (United States)

    Karaki, Samah; Becamel, Carine; Murat, Samy; Mannoury la Cour, Clotilde; Millan, Mark J.; Prézeau, Laurent; Bockaert, Joël; Marin, Philippe; Vandermoere, Franck

    2014-01-01

    The serotonin 5-HT2A receptor is a primary target of psychedelic hallucinogens such as lysergic acid diethylamine, mescaline, and psilocybin, which reproduce some of the core symptoms of schizophrenia. An incompletely resolved paradox is that only some 5-HT2A receptor agonists exhibit hallucinogenic activity, whereas structurally related agonists with comparable affinity and activity lack such a psychoactive activity. Using a strategy combining stable isotope labeling by amino acids in cell culture with enrichment in phosphorylated peptides by means of hydrophilic interaction liquid chromatography followed by immobilized metal affinity chromatography, we compared the phosphoproteome in HEK-293 cells transiently expressing the 5-HT2A receptor and exposed to either vehicle or the synthetic hallucinogen 1-[2,5-dimethoxy-4-iodophenyl]-2-aminopropane (DOI) or the nonhallucinogenic 5-HT2A agonist lisuride. Among the 5995 identified phosphorylated peptides, 16 sites were differentially phosphorylated upon exposure of cells to DOI versus lisuride. These include a serine (Ser280) located in the third intracellular loop of the 5-HT2A receptor, a region important for its desensitization. The specific phosphorylation of Ser280 by hallucinogens was further validated by quantitative mass spectrometry analysis of immunopurified receptor digests and by Western blotting using a phosphosite specific antibody. The administration of DOI, but not of lisuride, to mice, enhanced the phosphorylation of 5-HT2A receptors at Ser280 in the prefrontal cortex. Moreover, hallucinogens induced a less pronounced desensitization of receptor-operated signaling in HEK-293 cells and neurons than did nonhallucinogenic agonists. The mutation of Ser280 to aspartic acid (to mimic phosphorylation) reduced receptor desensitization by nonhallucinogenic agonists, whereas its mutation to alanine increased the ability of hallucinogens to desensitize the receptor. This study reveals a biased phosphorylation of

  1. Muscarinic receptor agonists stimulate matrix metalloproteinase 1-dependent invasion of human colon cancer cells

    Energy Technology Data Exchange (ETDEWEB)

    Raufman, Jean-Pierre, E-mail: jraufman@medicine.umaryland.edu [Division of Gastroenterology and Hepatology, University of Maryland School of Medicine, Baltimore, MD (United States); Cheng, Kunrong; Saxena, Neeraj; Chahdi, Ahmed; Belo, Angelica; Khurana, Sandeep; Xie, Guofeng [Division of Gastroenterology and Hepatology, University of Maryland School of Medicine, Baltimore, MD (United States)

    2011-11-18

    Highlights: Black-Right-Pointing-Pointer Muscarinic receptor agonists stimulated robust human colon cancer cell invasion. Black-Right-Pointing-Pointer Anti-matrix metalloproteinase1 antibody pre-treatment blocks cell invasion. Black-Right-Pointing-Pointer Bile acids stimulate MMP1 expression, cell migration and MMP1-dependent invasion. -- Abstract: Mammalian matrix metalloproteinases (MMPs) which degrade extracellular matrix facilitate colon cancer cell invasion into the bloodstream and extra-colonic tissues; in particular, MMP1 expression correlates strongly with advanced colon cancer stage, hematogenous metastasis and poor prognosis. Likewise, muscarinic receptor signaling plays an important role in colon cancer; muscarinic receptors are over-expressed in colon cancer compared to normal colon epithelial cells. Muscarinic receptor activation stimulates proliferation, migration and invasion of human colon cancer cells. In mouse intestinal neoplasia models genetic ablation of muscarinic receptors attenuates carcinogenesis. In the present work, we sought to link these observations by showing that MMP1 expression and activation plays a mechanistic role in muscarinic receptor agonist-induced colon cancer cell invasion. We show that acetylcholine, which robustly increases MMP1 expression, stimulates invasion of HT29 and H508 human colon cancer cells into human umbilical vein endothelial cell monolayers - this was abolished by pre-incubation with atropine, a non-selective muscarinic receptor inhibitor, and by pre-incubation with anti-MMP1 neutralizing antibody. Similar results were obtained using a Matrigel chamber assay and deoxycholyltaurine (DCT), an amidated dihydroxy bile acid associated with colon neoplasia in animal models and humans, and previously shown to interact functionally with muscarinic receptors. DCT treatment of human colon cancer cells resulted in time-dependent, 10-fold increased MMP1 expression, and DCT-induced cell invasion was also blocked by pre

  2. Muscarinic receptor agonists stimulate matrix metalloproteinase 1-dependent invasion of human colon cancer cells

    International Nuclear Information System (INIS)

    Highlights: ► Muscarinic receptor agonists stimulated robust human colon cancer cell invasion. ► Anti-matrix metalloproteinase1 antibody pre-treatment blocks cell invasion. ► Bile acids stimulate MMP1 expression, cell migration and MMP1-dependent invasion. -- Abstract: Mammalian matrix metalloproteinases (MMPs) which degrade extracellular matrix facilitate colon cancer cell invasion into the bloodstream and extra-colonic tissues; in particular, MMP1 expression correlates strongly with advanced colon cancer stage, hematogenous metastasis and poor prognosis. Likewise, muscarinic receptor signaling plays an important role in colon cancer; muscarinic receptors are over-expressed in colon cancer compared to normal colon epithelial cells. Muscarinic receptor activation stimulates proliferation, migration and invasion of human colon cancer cells. In mouse intestinal neoplasia models genetic ablation of muscarinic receptors attenuates carcinogenesis. In the present work, we sought to link these observations by showing that MMP1 expression and activation plays a mechanistic role in muscarinic receptor agonist-induced colon cancer cell invasion. We show that acetylcholine, which robustly increases MMP1 expression, stimulates invasion of HT29 and H508 human colon cancer cells into human umbilical vein endothelial cell monolayers – this was abolished by pre-incubation with atropine, a non-selective muscarinic receptor inhibitor, and by pre-incubation with anti-MMP1 neutralizing antibody. Similar results were obtained using a Matrigel chamber assay and deoxycholyltaurine (DCT), an amidated dihydroxy bile acid associated with colon neoplasia in animal models and humans, and previously shown to interact functionally with muscarinic receptors. DCT treatment of human colon cancer cells resulted in time-dependent, 10-fold increased MMP1 expression, and DCT-induced cell invasion was also blocked by pre-treatment with anti-MMP1 antibody. This study contributes to understanding

  3. A Novel Role of Serotonin Receptor 2B Agonist as an Anti-Melanogenesis Agent.

    Science.gov (United States)

    Oh, Eun Ju; Park, Jong Il; Lee, Ji Eun; Myung, Cheol Hwan; Kim, Su Yeon; Chang, Sung Eun; Hwang, Jae Sung

    2016-01-01

    BW723C86, a serotonin receptor 2B agonist, has been investigated as a potential therapeutic for various conditions such as anxiety, hyperphagia and hypertension. However, the functional role of BW723C86 against melanogenesis remains unclear. In this study, we investigate the effect of serotonin receptor 2B (5-HTR2B) agonist on melanogenesis and elucidate the mechanism involved. BW723C86 reduced melanin synthesis and intracellular tyrosinase activity in melan-A cells and normal human melanocytes. The expression of melanogenesis-related proteins (tyrosinase, TRP-1 and TRP-2) and microphthalmia-associated transcription factor (MITF) in melan-A cells decreased after BW723C86 treatment. The promoter activity of MITF was also reduced by BW723C86 treatment. The reduced level of MITF was associated with inhibition of protein kinase A (PKA) and cAMP response element-binding protein (CREB) activation by BW723C86 treatment. These results suggest that the serotonin agonist BW723C86 could be a potential therapeutic agent for skin hyperpigmentation disorders. PMID:27077852

  4. β2-Adrenergic receptor agonists activate CFTR in intestinal organoids and subjects with cystic fibrosis.

    Science.gov (United States)

    Vijftigschild, Lodewijk A W; Berkers, Gitte; Dekkers, Johanna F; Zomer-van Ommen, Domenique D; Matthes, Elizabeth; Kruisselbrink, Evelien; Vonk, Annelotte; Hensen, Chantal E; Heida-Michel, Sabine; Geerdink, Margot; Janssens, Hettie M; van de Graaf, Eduard A; Bronsveld, Inez; de Winter-de Groot, Karin M; Majoor, Christof J; Heijerman, Harry G M; de Jonge, Hugo R; Hanrahan, John W; van der Ent, Cornelis K; Beekman, Jeffrey M

    2016-09-01

    We hypothesized that people with cystic fibrosis (CF) who express CFTR (cystic fibrosis transmembrane conductance regulator) gene mutations associated with residual function may benefit from G-protein coupled receptor (GPCR)-targeting drugs that can activate and enhance CFTR function.We used intestinal organoids to screen a GPCR-modulating compound library and identified β2-adrenergic receptor agonists as the most potent inducers of CFTR function.β2-Agonist-induced organoid swelling correlated with the CFTR genotype, and could be induced in homozygous CFTR-F508del organoids and highly differentiated primary CF airway epithelial cells after rescue of CFTR trafficking by small molecules. The in vivo response to treatment with an oral or inhaled β2-agonist (salbutamol) in CF patients with residual CFTR function was evaluated in a pilot study. 10 subjects with a R117H or A455E mutation were included and showed changes in the nasal potential difference measurement after treatment with oral salbutamol, including a significant improvement of the baseline potential difference of the nasal mucosa (+6.35 mV, pCFTR activation when administered ex vivo to organoids.This proof-of-concept study suggests that organoids can be used to identify drugs that activate CFTR function in vivo and to select route of administration. PMID:27471203

  5. A Novel Role of Serotonin Receptor 2B Agonist as an Anti-Melanogenesis Agent

    Directory of Open Access Journals (Sweden)

    Eun Ju Oh

    2016-04-01

    Full Text Available BW723C86, a serotonin receptor 2B agonist, has been investigated as a potential therapeutic for various conditions such as anxiety, hyperphagia and hypertension. However, the functional role of BW723C86 against melanogenesis remains unclear. In this study, we investigate the effect of serotonin receptor 2B (5-HTR2B agonist on melanogenesis and elucidate the mechanism involved. BW723C86 reduced melanin synthesis and intracellular tyrosinase activity in melan-A cells and normal human melanocytes. The expression of melanogenesis-related proteins (tyrosinase, TRP-1 and TRP-2 and microphthalmia-associated transcription factor (MITF in melan-A cells decreased after BW723C86 treatment. The promoter activity of MITF was also reduced by BW723C86 treatment. The reduced level of MITF was associated with inhibition of protein kinase A (PKA and cAMP response element-binding protein (CREB activation by BW723C86 treatment. These results suggest that the serotonin agonist BW723C86 could be a potential therapeutic agent for skin hyperpigmentation disorders.

  6. Dopamine D3 receptor-preferring agonists induce neurotrophic effects on mesencephalic dopamine neurons.

    Science.gov (United States)

    Du, Fang; Li, Rui; Huang, Yuangui; Li, Xuping; Le, Weidong

    2005-11-01

    Anti-parkinsonian agents, pramipexole (PPX) and ropinirole (ROP), have been reported to possess neuroprotective properties, both in vitro and in vivo. The mechanisms underlying neuroprotection afforded by the D3-preferring receptor agonists remain poorly understood. The present study demonstrates that incubation of primary mesencephalic cultures with PPX and ROP or the conditioned medium from PPX- or ROP-treated primary cultures induced a marked increase in the number of dopamine (DA) neurons in the cultures. Similar effects can be observed after incubating with the conditioned medium derived from PPX- and ROP-treated substantia nigra astroglia. Meanwhile, PPX and ROP can protect the primary cells from insult of 1-methyl-4-phenylpyridinium (MPP+), the active metabolite of the neurotoxin 1-methyl-4-phenyl-1,2,5,6-tetrahydropyridine (MPTP). Furthermore, the neurotrophic effects of PPX and ROP on mesencephalic dopamine neurons could be significantly blocked by D3 receptor antagonist, but not by D2 receptor antagonist. Moreover, we found that the levels of glial cell line-derived neurotrophic factor (GDNF) and brain-derived neurotrophic factor (BDNF) in the conditioned medium of mesencephalic cultures treated with PPX and ROP were significantly increased. Blocking GDNF and BDNF with the neutralizing antibodies, the neurotrophic effects of PPX and ROP were greatly diminished. These results suggest that D3 dopamine receptor-preferring agonists, PPX and ROP, exert neurotrophic effects on cultured DA neurons by modulating the production of endogenous GDNF and BDNF, which may participate in their neuroprotection. PMID:16307585

  7. Selective agonists of retinoic acid receptors: comparative toxicokinetics and embryonic exposure.

    Science.gov (United States)

    Arafa, H M; Elmazar, M M; Hamada, F M; Reichert, U; Shroot, B; Nau, H

    2000-01-01

    Three biologically active synthetic retinoids were investigated that bind selectively to retinoic acid receptors RARs (alpha, beta and gamma). The retinoids were previously demonstrated to have different teratogenic effects in the mouse in terms of potency and regioselectivity. The teratogenic potency rank order (alpha >beta >gamma) was found to be more or less compatible with the receptor binding affinities and transactivation potencies of the retinoid ligands to their respective receptors. The RARalpha agonist (Am580; CD336) induced a wide spectrum of malformations; CD2019 (RARbeta agonist) and especially CD437 (RARgamma agonist) produced more restricted defects. In the current study we tried to address whether the differences in teratogenic effects are solely related to binding affinity and transactivation differences or also due to differences in embryonic exposure. Therefore, transplacental kinetics of the ligands were assessed following administration of a single oral dose of 15 mg/kg of either retinoid given to NMRI mice on day 11 of gestation. Am580 was rapidly transferred to the embryo resulting in the highest embryonic exposure [embryo to maternal plasma area under the time vs concentration curve (AUC)(0-24 h )ratio (E/M) was 1.7], in accordance with its highest teratogenic potency. The low placental transfer of CD2019 (E/M of 0.3) was compatible with its lower teratogenic potential. Of major interest was the finding that the CD437, though being least teratogenic, exhibited considerable embryonic exposure (E/M of 0.6). These findings suggest that both the embryonic exposure and receptor binding transactivation selectivity are crucial determinants of the teratogenicity of these retinoid ligands.

  8. Estradiol and Estrogen Receptor Agonists Oppose Oncogenic Actions of Leptin in HepG2 Cells.

    Science.gov (United States)

    Shen, Minqian; Shi, Haifei

    2016-01-01

    Obesity is a significant risk factor for certain cancers, including hepatocellular carcinoma (HCC). Leptin, a hormone secreted by white adipose tissue, precipitates HCC development. Epidemiology data show that men have a much higher incidence of HCC than women, suggesting that estrogens and its receptors may inhibit HCC development and progression. Whether estrogens antagonize oncogenic action of leptin is uncertain. To investigate potential inhibitory effects of estrogens on leptin-induced HCC development, HCC cell line HepG2 cells were treated with leptin in combination with 17 β-estradiol (E2), estrogen receptor-α (ER-α) selective agonist PPT, ER-β selective agonist DPN, or G protein-coupled ER (GPER) selective agonist G-1. Cell number, proliferation, and apoptosis were determined, and leptin- and estrogen-related intracellular signaling pathways were analyzed. HepG2 cells expressed a low level of ER-β mRNA, and leptin treatment increased ER-β expression. E2 suppressed leptin-induced HepG2 cell proliferation and promoted cell apoptosis in a dose-dependent manner. Additionally E2 reversed leptin-induced STAT3 and leptin-suppressed SOCS3, which was mainly achieved by activation of ER-β. E2 also enhanced ERK via activating ER-α and GPER and activated p38/MAPK via activating ER-β. To conclude, E2 and its receptors antagonize the oncogenic actions of leptin in HepG2 cells by inhibiting cell proliferation and stimulating cell apoptosis, which was associated with reversing leptin-induced changes in SOCS3/STAT3 and increasing p38/MAPK by activating ER-β, and increasing ERK by activating ER-α and GPER. Identifying roles of different estrogen receptors would provide comprehensive understanding of estrogenic mechanisms in HCC development and shed light on potential treatment for HCC patients. PMID:26982332

  9. A peroxisome proliferator-activated receptor-gamma agonist and other constituents from Chromolaena odorata.

    Science.gov (United States)

    Dat, Nguyen Tien; Lee, Kyeong; Hong, Young-Soo; Kim, Young Ho; Minh, Chau Van; Lee, Jung Joon

    2009-06-01

    Peroxisome proliferator-activated receptors (PPARs) are key regulators of lipid and glucose metabolism and have become important therapeutic targets for various diseases. The phytochemical investigation of the chloroform-soluble extract of Chromolaena odorata led to the isolation of a PPAR-gamma agonist, (9 S,13 R)-12-oxo-phytodienoic acid (1), together with 12 other compounds. The structures of chromomoric acid G (2), a new dehydrogenated derivative of 1, and chromolanone (3) were elucidated based on spectroscopic methods. Compound 1 showed a significant effect on PPAR-gamma activation in comparison with rosiglitazone. However, compound 2 was inactive, suggesting that the dehydrogenation of the prostaglandin-like structure in 1 abrogates its PPAR-gamma agonistic activity. PMID:19242902

  10. Liver X Receptor Agonists Inhibit the Phospholipid Regulatory Gene CTP: Phosphoethanolamine Cytidylyltransferase-Pcyt2

    Directory of Open Access Journals (Sweden)

    Lin Zhu

    2008-01-01

    Full Text Available Metabolic pulse-chase experiments demonstrated that 25-hydroxycholesterol (25-OH, the endogenous activator of the liver X receptor (LXR, significantly reduced the biosynthesis of phosphatidylethanolamine via CDP-ethanolamine (Kennedy pathway at the step catalyzed by CTP: phosphoethanolamine cytidylyltransferase (Pcyt2. In the mouse embryonic fibroblasts C3H10T1/2, the LXR synthetic agonist TO901317 lowered Pcyt2 promoter-luciferase activity in a concentration-dependent manner. Furthermore, 25-OH and TO901317 reduced mouse Pcyt2 mRNA and protein levels by 35–60%. The inhibitory effects of oxysterols and TO901317 on the Pcyt2 promoter function, mRNA and protein expression were conserved in the human breast cancer cells MCF-7. These studies identify the Pcyt2 gene as a novel target whereby LXR agonists may indirectly modulate inflammatory responses and atherosclerosis.

  11. CPG-7909 (PF-3512676, ProMune): toll-like receptor-9 agonist in cancer therapy.

    Science.gov (United States)

    Murad, Yanal M; Clay, Timothy M; Lyerly, H Kim; Morse, Michael A

    2007-08-01

    Stimulation of toll-like receptor (TLR)9 activates human plasmacytoid dendritic cells and B cells, and induces potent innate immune responses in preclinical tumor models and in patients. CpG oligodeoxynucleotides (ODNs) are TLR9 agonists that show promising results as vaccine adjuvants and in the treatment of cancers, infections, asthma and allergy. PF-3512676 (ProMune) was developed as a TLR9 agonist for the treatment of cancer as monotherapy and as an adjuvant in combination with chemo- and immunotherapy. Phase I and II trials have tested this drug in several hematopoietic and solid tumors. Pfizer has initiated Phase III trials to test PF-3512676 in combination with standard chemotherapy for non-small-cell lung cancer. PMID:17696823

  12. Design, synthesis and biological activity of flavonoid derivatives as selective agonists for neuromedin U 2 receptor.

    Science.gov (United States)

    Ma, Ming-Liang; Li, Ming; Gou, Jiao-Jiao; Ruan, Tian-Yu; Jin, Hai-Shan; Zhang, Ling-Hong; Wu, Liang-Chun; Li, Xiao-Yan; Hu, Ying-He; Wen, Ke; Zhao, Zheng

    2014-11-01

    Central neuromedin U 2 receptor (NMU2R) plays important roles in the regulation of food intake and body weight. Identification of NMU2R agonists may lead to the development of pharmaceutical agents to treat obesity. Based on the structure of rutin, a typical flavonoid and one of the NMU2R agonists we previously identified from an in-house made natural product library, 30 flavonoid derivatives have been synthesized and screened on a cell-based reporter gene assay. A number of compounds were found to be selective and highly potent to NMU2R. For example, the EC50 value of compound NRA 4 is very close to that of NMU, the endogenous peptide ligand of NMU2R. Structure-activity relationship analysis revealed that a 3-hydroxyl group in ring C and a 2'-fluoride group in ring B were essential for this class of compounds to be active against NMU2R. PMID:25262941

  13. Misoprostol, an anti-ulcer agent and PGE2 receptor agonist, protects against cerebral ischemia

    Science.gov (United States)

    Li, Jun; Liang, Xibin; Wang, Qian; Breyer, Richard M.; McCullough, Louise; Andreasson, Katrin

    2008-01-01

    Induction of COX-2 activity in cerebral ischemia results in increased neuronal injury and infarct size. Recent studies investigating neurotoxic mechanisms of COX-2 demonstrate both toxic and paradoxically protective effects of downstream prostaglandin receptor signaling pathways. We tested whether misoprostol, a PGE2 receptor agonist that is utilized clinically as an anti-ulcer agent and signals through the protective PGE2 EP2, EP3, and EP4 receptors, would reduce brain injury in the murine middle cerebral artery occlusion–reperfusion (MCAO-RP) model. Administration of misoprostol, at the time of MCAO or 2 h after MCAO, resulted in significant rescue of infarct volume at 24 and 72 h. Immunocytochemistry demonstrated dynamic regulation of the EP2 and EP4 receptors during reperfusion in neurons and endothelial cells of cerebral cortex and striatum, with limited expression of EP3 receptor. EP3−/− mice had no significant changes in infarct volume compared to control littermates. Moreover, administration of misoprostol to EP3+/+ and EP3−/− mice showed similar levels of infarct rescue, indicating that misoprostol protection was not mediated through the EP3 receptor. Taken together, these findings suggest a novel function for misoprostol as a protective agent in cerebral ischemia acting via the PGE2 EP2 and/or EP4 receptors. PMID:18472336

  14. Identification and optimization of small-molecule agonists of the human relaxin hormone receptor RXFP1.

    Science.gov (United States)

    Xiao, Jingbo; Huang, Zaohua; Chen, Catherine Z; Agoulnik, Irina U; Southall, Noel; Hu, Xin; Jones, Raisa E; Ferrer, Marc; Zheng, Wei; Agoulnik, Alexander I; Marugan, Juan J

    2013-01-01

    The anti-fibrotic, vasodilatory and pro-angiogenic therapeutic properties of recombinant relaxin peptide hormone have been investigated in several diseases, and recent clinical trial data has shown benefit in treating acute heart failure. However, the remodelling capacity of these peptide hormones is difficult to study in chronic settings because of their short half-life and the need for intravenous administration. Here we present the first small-molecule series of human relaxin/insulin-like family peptide receptor 1 agonists. These molecules display similar efficacy as the natural hormone in several functional assays. Mutagenesis studies indicate that the small molecules activate relaxin receptor through an allosteric site. These compounds have excellent physical and in vivo pharmacokinetic properties to support further investigation of relaxin biology and animal efficacy studies of the therapeutic benefits of relaxin/insulin-like family peptide receptor 1 activation. PMID:23764525

  15. Conversion of agonist site to metal-ion chelator site in the beta(2)-adrenergic receptor

    DEFF Research Database (Denmark)

    Elling, C E; Thirstrup, K; Holst, Birgitte;

    1999-01-01

    in the mutant receptors not by normal catecholamine ligands but instead either by free zinc ions or by zinc or copper ions in complex with small hydrophobic metal-ion chelators. Chelation of the metal ions by small hydrophobic chelators such as phenanthroline or bipyridine protected the cells from the toxic...... effect of, for example Cu(2+), and in several cases increased the affinity of the ions for the agonistic site. Wash-out experiments and structure-activity analysis indicated, that the high-affinity chelators and the metal ions bind and activate the mutant receptor as metal ion guided ligand complexes....... Because of the well-understood binding geometry of the small metal ions, an important distance constraint has here been imposed between TM-III and -VII in the active, signaling conformation of 7TM receptors. It is suggested that atoxic metal-ion chelator complexes could possibly in the future be used...

  16. Revealing a steroid receptor ligand as a unique PPARγagonist

    Institute of Scientific and Technical Information of China (English)

    Shengchen Lin; Ying Han; Yuzhe Shi; Hui Rong; Songyang Zheng; Shikan Jin; Shu-Yong Lin; Sheng-Cai Lin; Yong Li

    2012-01-01

    Peroxisome proliferator-activated receptor gamma (PPARγ) regulates metabolic homeostasis and is a molecular target for anti-diabetic drugs.We report here the identification of a steroid receptor ligand,RU-486,as an unexpected PPARγ agonist,thereby uncovering a novel signaling route for this steroid drug.Similar to rosiglitazone,RU486 modulates the expression of key PPARγ target genes and promotes adipocyte differentiation,but with a lower adipogenic activity.Structural and functional studies of receptor-ligand interactions reveal the molecular basis for a unique binding mode for RU-486 in the PPARγ ligand-binding pocket with distinctive properties and epitopes,providing the molecular mechanisms for the discrimination of RU-486 from thiazolidinediones (TZDs) drugs.Our findings together indicate that steroid compounds may represent an alternative approach for designing non-TZD PPARγligands in the treatment of insulin resistance.

  17. Revealing a steroid receptor ligand as a unique PPAR[gamma] agonist

    Energy Technology Data Exchange (ETDEWEB)

    Lin, Shengchen; Han, Ying; Shi, Yuzhe; Rong, Hui; Zheng, Songyang; Jin, Shikan; Lin, Shu-Yong; Lin, Sheng-Cai; Li, Yong (Pitt); (Xiamen)

    2012-06-28

    Peroxisome proliferator-activated receptor gamma (PPAR{gamma}) regulates metabolic homeostasis and is a molecular target for anti-diabetic drugs. We report here the identification of a steroid receptor ligand, RU-486, as an unexpected PPAR{gamma} agonist, thereby uncovering a novel signaling route for this steroid drug. Similar to rosiglitazone, RU-486 modulates the expression of key PPAR{gamma} target genes and promotes adipocyte differentiation, but with a lower adipogenic activity. Structural and functional studies of receptor-ligand interactions reveal the molecular basis for a unique binding mode for RU-486 in the PPAR{gamma} ligand-binding pocket with distinctive properties and epitopes, providing the molecular mechanisms for the discrimination of RU-486 from thiazolidinediones (TZDs) drugs. Our findings together indicate that steroid compounds may represent an alternative approach for designing non-TZD PPAR{gamma} ligands in the treatment of insulin resistance.

  18. Evidence that the angiotensin at 2-receptor agonist compound 21 is also a low affinity thromboxane TXA2-receptor antagonist

    DEFF Research Database (Denmark)

    Fredgart, M.; Leurgans, T.; Stenelo, M.;

    2015-01-01

    Objective: The objective of this study was to test whether Compound 21 (C21), a high-affinity, non-peptide angiotensinAT2-receptor agonist, is also an antagonist of thromboxane A2 (TXA2) receptors thus reducing both vasoconstriction and platelet aggregation. Design and method: Binding of C21 to the...... TXA2 receptor was determined by TBXA2R Arrestin Biosensor Assay. Mouse mesenteric arteries were mounted in wire myographs, and responses to increasing concentrations of C21 (1nM- 10muM) were recorded during submaximal contractions with 0.1muM U46619 (TXA2 analogue) or 1muMphenylephrine. To control for...

  19. Apparent Inverse Relationship between Cannabinoid Agonist Efficacy and Tolerance/Cross-Tolerance Produced by Δ9-Tetrahydrocannabinol Treatment in Rhesus Monkeys

    OpenAIRE

    Hruba, Lenka; Ginsburg, Brett C.; McMahon, Lance R.

    2012-01-01

    Synthetic cannabinoids (CBs) [naphthalen-1-yl-(1-pentylindol-3-yl) methanone (JWH-018) and naphthalen-1-yl-(1-butylindol-3-yl) methanone (JWH-073)] are marketed, sold, and used as alternatives to cannabis. Synthetic CBs appear to have effects similar to those of Δ9-tetrahydrocannabinol (Δ9-THC), the drug primarily responsible for the behavioral effects of cannabis. However, synthetic CB products produce atypical effects (e.g., hypertension, seizures, and panic attacks). One potential explanat...

  20. Structural Determinants for the Binding of Morphinan Agonists to the μ-Opioid Receptor.

    Directory of Open Access Journals (Sweden)

    Xiaojing Cong

    Full Text Available Atomistic descriptions of the μ-opioid receptor (μOR noncovalently binding with two of its prototypical morphinan agonists, morphine (MOP and hydromorphone (HMP, are investigated using molecular dynamics (MD simulations. Subtle differences between the binding modes and hydration properties of MOP and HMP emerge from the calculations. Alchemical free energy perturbation calculations show qualitative agreement with in vitro experiments performed in this work: indeed, the binding free energy difference between MOP and HMP computed by forward and backward alchemical transformation is 1.2±1.1 and 0.8±0.8 kcal/mol, respectively, to be compared with 0.4±0.3 kcal/mol from experiment. Comparison with an MD simulation of μOR covalently bound with the antagonist β-funaltrexamine hints to agonist-induced conformational changes associated with an early event of the receptor's activation: a shift of the transmembrane helix 6 relative to the transmembrane helix 3 and a consequent loss of the key R165-T279 interhelical hydrogen bond. This finding is consistent with a previous proposal suggesting that the R165-T279 hydrogen bond between these two helices indicates an inactive receptor conformation.

  1. Effects of the neurotensin NTS₁ receptor agonist PD149163 on visual signal detection in rats.

    Science.gov (United States)

    Hillhouse, Todd M; Prus, Adam J

    2013-12-01

    Antipsychotic drugs provide limited efficacy for cognitive impairment in schizophrenia. Recent studies have found that the neurotensin NTS1 receptor agonist and putative atypical antipsychotic drug PD149163 reverses deficits in sensory-gating and novel object recognition, suggesting that this compound may have the potential to improve cognitive functioning in schizophrenia. The present study sought to extend these investigations by evaluating the effects of PD149163 on sustained attention using a visual signal detection operant task in rats. PD149163, the atypical antipsychotic drug clozapine, and the dopamine D2/3 receptor antagonist raclopride all significantly decreased percent "hit" accuracy, while none of these compounds altered "correct rejections" (compared to vehicle control). Clozapine and raclopride significantly increased response latency, while high doses of PD149163 and raclopride significantly increased trial omissions. Nicotine, which was tested as a positive control, significantly improved overall performance in this task and did not affect response latency or trial omissions. The present findings suggest that neurotensin NTS1 receptor agonists, like antipsychotic drugs, may inhibit sustained attention in this task despite having different pharmacological mechanisms of action.

  2. Effects of the 5-HT(4) receptor agonist RS67333 and paroxetine on hippocampal extracellular 5-HT levels

    DEFF Research Database (Denmark)

    Licht, Cecilie Löe; Knudsen, Gitte Moos; Sharp, Trevor

    2010-01-01

    The 5-HT(4) receptor modulates activity of serotonergic neurons and is a new potential target for antidepressant treatment. This microdialysis study evaluated the effect of the 5-HT(4) receptor agonist, RS67333, on extracellular serotonin (5-hydroxytryptamine, 5-HT) and 5-HIAA levels in rat ventr...

  3. Antipsychotic-like effect of the muscarinic acetylcholine receptor agonist BuTAC in non-human primates

    DEFF Research Database (Denmark)

    Andersen, Maibritt B; Croy, Carrie Hughes; Dencker, Ditte;

    2015-01-01

    Cholinergic, muscarinic receptor agonists exhibit functional dopamine antagonism and muscarinic receptors have been suggested as possible future targets for the treatment of schizophrenia and drug abuse. The muscarinic ligand (5R,6R)-6-(3-butylthio-1,2,5-thiadiazol-4-yl)-1-azabicyclo[3.2.1]octane...

  4. GR43175, a selective agonist for the 5-HT1-like receptor in dog isolated saphenous vein.

    OpenAIRE

    Humphrey, P. P.; Feniuk, W.; Perren, M. J.; Connor, H. E.; Oxford, A. W.; Coates, L. H.; Butina, D.

    1988-01-01

    1. We describe the actions of a novel and selective 5-HT1-like receptor agonist, GR43175, in a range of isolated tissue preparations containing different 5-hydroxytryptamine (5-HT) receptor types. 2. GR43175 was a potent agonist at 5-HT1-like receptors mediating contraction of the dog isolated saphenous vein and also at those inhibiting neuronally mediated contractions in the same preparations. For both actions, GR43175 was approximately four times weaker than 5-HT. 3. GR43175 was devoid of a...

  5. Preventing or attenuating amphotericin B nephrotoxicity with dopamine receptor agonists: a literature review

    Directory of Open Access Journals (Sweden)

    Iman Karimzadeh

    2016-09-01

    Full Text Available Nephrotoxicity is generally considered as the most clinically significant and dose-limiting adverse reaction of amphotericin B. Currently, only the clinical effectiveness of salt loading and administering lipid formulations of amphotericin B have been clearly demonstrated to prevent its nephrotoxicity. In this review, we collected the published data related to dopamine receptor agonists in preventing amphotericin B nephrotoxicity. A literature search was conducted by the relevant keywords like ‘‘amphotericin B”, “nephrotoxicity’’, and ‘‘dopamine’’in databases such as Scopus, Medline, Embase and ISI Web of Knowledge. Four relevant articles were considered. Results of all the 3 experimental studies demonstrated that co-administration of dopamine (0.5-10 μg/kg/min as continuous intravenous infusion, SK&F R-105058, a prodrug of fenoldopam (10 mg/kg twice daily, orally or fenoldopam, a relatively selective dopamine receptor type 1 agonist, (0.5 or 1 μg/kg/min as continuous intravenous infusion can at least significantly mitigate the decrease in creatinine clearance caused by amphotericin B. Furthermore, fenoldopam and SK&F R-105058 can also protect against or delay amphotericin B-induced tubular damage. In contrast, the only clinical trial published until now found that simultaneous continuous intravenous infusion of low dose dopamine (3 μg/kg/min had no beneficial effect on the incidence, severity and time onset of developing amphotericin B-induced nephrotoxicity in autologous bone marrow transplant and leukemia patients. Considering the lack of beneficial effects in different settings such as acute kidney injury of any cause, negative results of the only clinical trial, and risk of significant adverse reactions, continuous intravenous infusion of low dose dopamine (1-3 μg/kg/min or selective dopamine receptor type 1 agonists (e.g., fenoldopam currently appears to have no promising clinical role in preventing or attenuating

  6. Synthetic partial agonists reveal key steps in IP3 receptor activation

    OpenAIRE

    Rossi, Ana M.; Riley, Andrew M.; Stephen C Tovey; Taufiq-Ur-Rahman,; Dellis, Olivier; Taylor, Emily J A; Veresov, Valery G.; Potter, Barry V L; Taylor, Colin W.

    2009-01-01

    Inositol 1,4,5-trisphosphate receptors (IP3R) are ubiquitous intracellular Ca2+ channels. IP3binding to the IP3-binding core (IBC) near the N-terminal initiates conformational changes that lead to opening of a pore. The mechanisms are unresolved. We synthesized 2-O-modified IP3 analogues that are partial agonists of IP3R. These are like IP3 in their interactions with the IBC, but they are less effective than IP3 in rearranging the relationship between the IBC and N-terminal suppressor domain ...

  7. Characterization of Natural Aryl Hydrocarbon Receptor Agonists from Cassia Seed and Rosemary

    OpenAIRE

    Yoshiaki Amakura; Morio Yoshimura; Masashi Takaoka; Haruka Toda; Tomoaki Tsutsumi; Rieko Matsuda; Reiko Teshima; Masafumi Nakamura; Hiroshi Handa; Takashi Yoshida

    2014-01-01

    Many recent studies have suggested that activation of the aryl hydrocarbon receptor (AhR) reduces immune responses, thus suppressing allergies and autoimmune diseases. In our continuing study on natural AhR agonists in foods, we examined the influence of 37 health food materials on the AhR using a reporter gene assay, and found that aqueous ethanol extracts of cassia seed and rosemary had particularly high AhR activity. To characterize the AhR-activating substances in these samples, the chemi...

  8. Impact of the AT(2) receptor agonist C21 on blood pressure and beyond

    DEFF Research Database (Denmark)

    Foulquier, Sébastien; Steckelings, Ulrike Muscha; Unger, Thomas

    2012-01-01

    It is now widely accepted that the angiotensin AT(2) receptor (AT(2)R) plays an important protective role during pathophysiologic conditions, acting as a repair system. The development of the first selective nonpeptide AT(2)R agonist C21 accelerated our understanding of AT(2)R-mediated protective...... signaling and actions. This article reviews the impact of C21 on blood pressure in normotensive and hypertensive animal models. Although C21 does not act as a classical antihypertensive drug, it could be useful in preventing hypertension-induced vascular and other end organ damages via anti-apoptotic, anti...

  9. Discovery of acylurea isosteres of 2-acylaminothiadiazole in the azaxanthene series of glucocorticoid receptor agonists.

    Science.gov (United States)

    Gong, Hua; Yang, Michael; Xiao, Zili; Doweyko, Arthur M; Cunningham, Mark; Wang, Jinhong; Habte, Sium; Holloway, Deborah; Burke, Christine; Shuster, David; Gao, Ling; Carman, Julie; Somerville, John E; Nadler, Steven G; Salter-Cid, Luisa; Barrish, Joel C; Weinstein, David S

    2014-08-01

    Acylureas and acyclic imides are found to be excellent isosteres for 2-acylamino-1,3,4-thiadiazole in the azaxanthene-based series of glucocorticoid receptor (GR) agonists. The results reported herein show that primary acylureas maintain high affinity and selectivity for GR while providing improved CYP450 inhibition and pharmacokinetic profile over 2-acylamino-1,3,4-thiadiazoles. General methods for synthesis of a variety of acylureas and acyclic imides from a carboxylic acid were utilized and are described. PMID:24980053

  10. The angiotensin type 2 receptor agonist Compound 21 elicits cerebroprotection in endothelin-1 induced ischemic stroke

    DEFF Research Database (Denmark)

    Joseph, Jason P; Mecca, Adam P; Regenhardt, Robert W;

    2014-01-01

    Evidence indicates that angiotensin II type 2 receptors (AT2R) exert cerebroprotective actions during stroke. A selective non-peptide AT2R agonist, Compound 21 (C21), has been shown to exert beneficial effects in models of cardiac and renal disease, as well as hemorrhagic stroke. Here, we...... artery occlusion (MCAO), a model of cerebral ischemia. Rats infused centrally (intracerebroventricular) with C21 before endothelin-1 induced MCAO exhibited significant reductions in cerebral infarct size and the neurological deficits produced by cerebral ischemia. Similar cerebroprotection was obtained...

  11. Improvement in psoriasis after treatment with the glucagon-like peptide-1 receptor agonist liraglutide

    DEFF Research Database (Denmark)

    Faurschou, A; Knop, F K; Thyssen, J P;

    2011-01-01

    A 59-year old man with moderate and stable psoriasis through 15 years was admitted to our Department with inadequately controlled type 2 diabetes. Treatment was initiated with the glucagon-like peptide-1 receptor (GLP-1R) agonist liraglutide. The patient experienced marked improvement in his...... psoriasis immediately after the start of liraglutide treatment. Itching stopped within days, scaling was reduced and spots of normal skin emerged. After 3 months, psoriasis was still improving. Excellent glycaemic control and a weight loss of approximately 8 kg over 3 months were moreover obtained...

  12. Conformational variability of the glycine receptor M2 domain in response to activation by different agonists

    DEFF Research Database (Denmark)

    Pless, Stephan Alexander; Dibas, Mohammed I; Lester, Henry A;

    2007-01-01

    change. Although taurine and beta-alanine were weak partial agonists at the alpha1R19'C glycine receptor, they induced large fluorescence changes. Propofol, which drastically enhanced these currents, did not induce a glycine-like blue shift in the spectral emission peak. The inhibitors strychnine...... and picrotoxin elicited fluorescence and current changes as expected for a competitive antagonist and an open channel blocker, respectively. Glycine and taurine (or beta-alanine) also produced an increase and a decrease, respectively, in the fluorescence of a label attached to the nearby L22'C residue. Thus...

  13. Treatment of type 2 diabetes with glucagon-like peptide-1 receptor agonists

    DEFF Research Database (Denmark)

    Hansen, K B; Knop, F K; Holst, Jens Juul;

    2009-01-01

    The incretin system is an area of great interest for the development of new therapies for the management of type 2 diabetes. Existing antidiabetic drugs are often insufficient at getting patients to glycaemic goals. Furthermore, current treatment modalities are not able to prevent the continued...... of hypoglycaemia with GLP-1 receptor agonists is low, the compounds have clinically relevant effects on body weight, and data are suggesting beneficial effects on cardiovascular risk factors. Exenatide was released in 2005 for the treatment of type 2 diabetes and liraglutide is expected to be approved by the Food...

  14. CANNABINOID AND OPIOID MODULATION OF SOCIAL PLAY BEHAVIOR IN ADOLESCENT RATS: DIFFERENTIAL BEHAVIORAL MECHANISMS

    OpenAIRE

    Trezza, Viviana; Vanderschuren, Louk J. M. J.

    2008-01-01

    We have recently shown that the pharmacological mechanisms through which cannabinoid and opioid drugs influence social play behavior in adolescent rats can be partially dissociated. Here, we characterize the effects of the direct cannabinoid agonist WIN55,212-2, the indirect cannabinoid agonist URB597 and the opioid agonist morphine on social play at the behavioral level. By treating either one or both partners of the test dyad, we show that these drugs differentially affect play solicitation...

  15. The cannabinoid CB1 receptor and mTORC1 signalling pathways interact to modulate glucose homeostasis in mice.

    Science.gov (United States)

    Bermudez-Silva, Francisco J; Romero-Zerbo, Silvana Y; Haissaguerre, Magalie; Ruz-Maldonado, Inmaculada; Lhamyani, Said; El Bekay, Rajaa; Tabarin, Antoine; Marsicano, Giovanni; Cota, Daniela

    2016-01-01

    The endocannabinoid system (ECS) is an intercellular signalling mechanism that is present in the islets of Langerhans and plays a role in the modulation of insulin secretion and expansion of the β-cell mass. The downstream signalling pathways mediating these effects are poorly understood. Mammalian target of rapamycin complex 1 (mTORC1) signalling is a key intracellular pathway involved in energy homeostasis and is known to importantly affect the physiology of pancreatic islets. We investigated the possible relationship between cannabinoid type 1 (CB1) receptor signalling and the mTORC1 pathway in the endocrine pancreas of mice by using pharmacological analysis as well as mice genetically lacking the CB1 receptor or the downstream target of mTORC1, the kinase p70S6K1. In vitro static secretion experiments on islets, western blotting, and in vivo glucose and insulin tolerance tests were performed. The CB1 receptor antagonist rimonabant decreased glucose-stimulated insulin secretion (GSIS) at 0.1 µM while increasing phosphorylation of p70S6K1 and ribosomal protein S6 (rpS6) within the islets. Specific pharmacological blockade of mTORC1 by 3 nM rapamycin, as well as genetic deletion of p70S6K1, impaired the CB1-antagonist-mediated decrease in GSIS. In vivo experiments showed that 3 mg/kg body weight rimonabant decreased insulin levels and induced glucose intolerance in lean mice without altering peripheral insulin sensitivity; this effect was prevented by peripheral administration of low doses of rapamycin (0.1 mg/kg body weight), which increased insulin sensitivity. These findings suggest a functional interaction between the ECS and the mTORC1 pathway within the endocrine pancreas and at the whole-organism level, which could have implications for the development of new therapeutic approaches for pancreatic β-cell diseases.

  16. Clinical Significance of Cannabinoid Receptors CB1 and CB2 Expression in Human Malignant and Benign Thyroid Lesions.

    Science.gov (United States)

    Lakiotaki, Eleftheria; Giaginis, Constantinos; Tolia, Maria; Alexandrou, Paraskevi; Delladetsima, Ioanna; Giannopoulou, Ioanna; Kyrgias, George; Patsouris, Efstratios; Theocharis, Stamatios

    2015-01-01

    The endocannabinoid system is comprised of cannabinoid receptors (CB1 and CB2), their endogenous ligands (endocannabinoids), and proteins responsible for their metabolism participate in many different functions indispensable to homeostatic regulation in several tissues, exerting also antitumorigenic effects. The present study aimed to evaluate the clinical significance of CB1 and CB2 expression in human benign and malignant thyroid lesions. CB1 and CB2 proteins' expression was assessed immunohistochemically on paraffin-embedded thyroid tissues obtained from 87 patients with benign (n = 43) and malignant (n = 44) lesions and was statistically analyzed with clinicopathological parameters, follicular cells' proliferative capacity, and risk of recurrence rate estimated according to the American Thyroid Association (ATA) staging system. Enhanced CB1 and CB2 expression was significantly more frequently observed in malignant compared to benign thyroid lesions (p = 0.0010 and p = 0.0005, resp.). Enhanced CB1 and CB2 expression was also significantly more frequently observed in papillary carcinomas compared to hyperplastic nodules (p = 0.0097 and p = 0.0110, resp.). In malignant thyroid lesions, elevated CB2 expression was significantly associated with the presence of lymph node metastases (p = 0.0301). Enhanced CB2 expression was also more frequently observed in malignant thyroid cases with presence of capsular (p = 0.1165), lymphatic (p = 0.1989), and vascular invasion (p = 0.0555), as well as in those with increased risk of recurrence rate (p = 0.1165), at a nonsignificant level though, whereas CB1 expression was not associated with any of the clinicopathological parameters examined. Our data suggest that CB receptors may be involved in malignant thyroid transformation and especially CB2 receptor could serve as useful biomarker and potential therapeutic target in thyroid neoplasia.

  17. Clinical Significance of Cannabinoid Receptors CB1 and CB2 Expression in Human Malignant and Benign Thyroid Lesions

    Directory of Open Access Journals (Sweden)

    Eleftheria Lakiotaki

    2015-01-01

    Full Text Available The endocannabinoid system is comprised of cannabinoid receptors (CB1 and CB2, their endogenous ligands (endocannabinoids, and proteins responsible for their metabolism participate in many different functions indispensable to homeostatic regulation in several tissues, exerting also antitumorigenic effects. The present study aimed to evaluate the clinical significance of CB1 and CB2 expression in human benign and malignant thyroid lesions. CB1 and CB2 proteins’ expression was assessed immunohistochemically on paraffin-embedded thyroid tissues obtained from 87 patients with benign (n=43 and malignant (n=44 lesions and was statistically analyzed with clinicopathological parameters, follicular cells’ proliferative capacity, and risk of recurrence rate estimated according to the American Thyroid Association (ATA staging system. Enhanced CB1 and CB2 expression was significantly more frequently observed in malignant compared to benign thyroid lesions (p=0.0010 and p=0.0005, resp.. Enhanced CB1 and CB2 expression was also significantly more frequently observed in papillary carcinomas compared to hyperplastic nodules (p=0.0097 and p=0.0110, resp.. In malignant thyroid lesions, elevated CB2 expression was significantly associated with the presence of lymph node metastases (p=0.0301. Enhanced CB2 expression was also more frequently observed in malignant thyroid cases with presence of capsular (p=0.1165, lymphatic (p=0.1989, and vascular invasion (p=0.0555, as well as in those with increased risk of recurrence rate (p=0.1165, at a nonsignificant level though, whereas CB1 expression was not associated with any of the clinicopathological parameters examined. Our data suggest that CB receptors may be involved in malignant thyroid transformation and especially CB2 receptor could serve as useful biomarker and potential therapeutic target in thyroid neoplasia.

  18. Agonists of the tissue-protective erythropoietin receptor in the treatment of Parkinson's disease.

    Science.gov (United States)

    Punnonen, Juha; Miller, James L; Collier, Timothy J; Spencer, Jeffrey R

    2015-01-01

    Parkinson's disease (PD) is a neurodegenerative disease affecting more than a million people in the USA alone. While there are effective symptomatic treatments for PD, there is an urgent need for new therapies that slow or halt the progressive death of dopaminergic neurons. Significant progress has been made in understanding the pathophysiology of PD, which has substantially facilitated the discovery efforts to identify novel drugs. The tissue-protective erythropoietin (EPO) receptor, EPOR/CD131, has emerged as one promising target for disease-modifying therapies. Recombinant human EPO (rhEPO), several variants of EPO, EPO-mimetic peptides, cell-based therapies using cells incubated with or expressing EPO, gene therapy vectors encoding EPO, and small molecule EPO mimetic compounds all show potential as therapeutic candidates. Agonists of the EPOR/CD131 receptor demonstrate potent anti-apoptotic, antioxidant, and anti-inflammatory effects and protect neurons, including dopaminergic neurons, from diverse insults in vitro and in vivo. When delivered directly to the striatum, rhEPO protects dopaminergic neurons in animal models of PD. Early-stage clinical trials testing systemic rhEPO have provided encouraging results, while additional controlled studies are required to fully assess the potential of the treatment. Poor CNS availability of proteins and challenges related to invasive delivery limit delivery of EPO protein. Several variants of EPO and small molecule agonists of the EPO receptors are making progress in preclinical studies and may offer solutions to these challenges. While EPO was initially discovered as the primary modulator of erythropoiesis, the discovery and characterization of the tissue-protective EPOR/CD131 receptor offer an opportunity to selectively target the neuroprotective receptor as an approach to identify disease-modifying treatments for PD. PMID:25832721

  19. Predicting novel binding modes of agonists to β adrenergic receptors using all-atom molecular dynamics simulations.

    Directory of Open Access Journals (Sweden)

    Stefano Vanni

    Full Text Available Understanding the binding mode of agonists to adrenergic receptors is crucial to enabling improved rational design of new therapeutic agents. However, so far the high conformational flexibility of G protein-coupled receptors has been an obstacle to obtaining structural information on agonist binding at atomic resolution. In this study, we report microsecond classical molecular dynamics simulations of β(1 and β(2 adrenergic receptors bound to the full agonist isoprenaline and in their unliganded form. These simulations show a novel agonist binding mode that differs from the one found for antagonists in the crystal structures and from the docking poses reported by in silico docking studies performed on rigid receptors. Internal water molecules contribute to the stabilization of novel interactions between ligand and receptor, both at the interface of helices V and VI with the catechol group of isoprenaline as well as at the interface of helices III and VII with the ethanolamine moiety of the ligand. Despite the fact that the characteristic N-C-C-OH motif is identical in the co-crystallized ligands and in the full agonist isoprenaline, the interaction network between this group and the anchor site formed by Asp(3.32 and Asn(7.39 is substantially different between agonists and inverse agonists/antagonists due to two water molecules that enter the cavity and contribute to the stabilization of a novel network of interactions. These new binding poses, together with observed conformational changes in the extracellular loops, suggest possible determinants of receptor specificity.

  20. Cannabinoids reduce ErbB2-driven breast cancer progression through Akt inhibition

    Directory of Open Access Journals (Sweden)

    Flores Juana M

    2010-07-01

    Full Text Available Abstract Background ErbB2-positive breast cancer is characterized by highly aggressive phenotypes and reduced responsiveness to standard therapies. Although specific ErbB2-targeted therapies have been designed, only a small percentage of patients respond to these treatments and most of them eventually relapse. The existence of this population of particularly aggressive and non-responding or relapsing patients urges the search for novel therapies. The purpose of this study was to determine whether cannabinoids might constitute a new therapeutic tool for the treatment of ErbB2-positive breast tumors. We analyzed their antitumor potential in a well established and clinically relevant model of ErbB2-driven metastatic breast cancer: the MMTV-neu mouse. We also analyzed the expression of cannabinoid targets in a series of 87 human breast tumors. Results Our results show that both Δ9-tetrahydrocannabinol, the most abundant and potent cannabinoid in marijuana, and JWH-133, a non-psychotropic CB2 receptor-selective agonist, reduce tumor growth, t