WorldWideScience

Sample records for cannabinoid receptor agonists

  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. Novel endogenous peptide agonists of cannabinoid receptors

    OpenAIRE

    Gomes, Ivone; Grushko, Julia S.; Golebiewska, Urszula; Hoogendoorn, Sascha; Gupta, Achla; Heimann, Andrea S.; Ferro, Emer S.; Scarlata, Suzanne; Fricker, Lloyd D.; Devi, Lakshmi A.

    2009-01-01

    Hemopressin (Hp), a 9-residue α-hemoglobin-derived peptide, was previously reported to function as a CB1 cannabinoid receptor antagonist (1). In this study, we report that mass spectrometry (MS) data from peptidomics analyses of mouse brain extracts identified N-terminally extended forms of Hp containing either three (RVD-Hpα) or two (VD-Hpα) additional amino acids, as well as a β-hemoglobin-derived peptide with sequence similarity to that of hemopressin (VD-Hpβ). Characterization of the α-he...

  3. Inhibition of the production of endothelium-derived hyperpolarizing factor by cannabinoid receptor agonists

    OpenAIRE

    Fleming, I.; Schermer, B; Popp, R; Busse, R.

    1999-01-01

    The endogenous cannabinoid, anandamide, has been reported to induce an 'endothelium-derived hyperpolarizing factor (EDHF)-like' relaxation in vitro. We therefore investigated the effects of cannabinoid CB1 receptor agonists; HU 210, Δ9-tetrahydrocannabinol (Δ9-THC) and anandamide, and a CB1 antagonist/inverse agonist, SR 141716A, on nitric oxide (NO) and EDHF-mediated relaxation in precontracted rings of porcine coronary, rabbit carotid and mesenteric arteries.In rings of mesenteric artery HU...

  4. 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

  5. Differential Effects of Cannabinoid Receptor Agonist on Social Discrimination and Contextual Fear in Amygdala and Hippocampus

    Science.gov (United States)

    Segev, Amir; Akirav, Irit

    2011-01-01

    We examined whether the cannabinoid receptor agonist WIN55,212-2 (WIN; 5 [mu]g/side) microinjected into the hippocampus or the amygdala would differentially affect memory processes in a neutral vs. an aversive task. In the aversive contextual fear task, WIN into the basolateral amygdala impaired fear acquisition/consolidation, but not retrieval.…

  6. Intrathecal cannabinoid-1 receptor agonist prevents referred hyperalgesia in acute acrolein-induced cystitis in rats

    OpenAIRE

    Jones, Marsha Ritter; Wang, Zun-Yi; Bjorling, Dale E

    2015-01-01

    We investigated the capacity of intrathecal arachidonyl-2’-chloroethylamide (ACEA), a cannabinoid-1 receptor (CB1R) agonist, to inhibit referred hyperalgesia and increased bladder contractility resulting from acute acrolein-induced cystitis in rats. 24 female rats were divided into 4 groups: 1) intrathecal vehicle/intravesical saline; 2) intrathecal vehicle/intravesical acrolein; 3) intrathecal ACEA/intravesical saline; and 4) intrathecal ACEA/intravesical acrolein. Bladder catheters were pla...

  7. Intracerebroventricular injections of dronabinol, a cannabinoid receptor agonist, does not attenuate serotonin-induced apnea in Sprague-Dawley rats

    OpenAIRE

    Calik, Michael W.; Carley, David W

    2016-01-01

    Background Evidence suggests that vagal nerve activity may play a role in sleep apnea induction. In anesthetized rats, dronabinol, a cannabinoid (CB) receptor agonist, injected into the nodose ganglia attenuates reflex apnea and increases genioglossus activity, and reflex apnea attenuation is blocked by systemic pre-treatment with cannabinoid type 1 and/or type 2 receptor antagonists. However, it is unclear whether dronabinol has similar effects in the central nervous system; CB receptors are...

  8. Oleamide is a selective endogenous agonist of rat and human CB1 cannabinoid receptors

    OpenAIRE

    Leggett, James D; Aspley, S; Beckett, S R G; D'Antona, A M; Kendall, D A

    2004-01-01

    The ability of the endogenous fatty acid amide, cis-oleamide (ODA), to bind to and activate cannabinoid CB1 and CB2 receptors was investigated.ODA competitively inhibited binding of the nonselective cannabinoid agonist [3H]CP55,940 and the selective CB1 antagonist [3H]SR141716A to rat whole-brain membranes with Ki values of 1.14 μM (0.52–2.53 μM, Hill slope=0.80, n=6) and 2.63 μM (0.62–11.20 μM, Hill slope=0.92, n=4), respectively. AEA inhibited [3H]CP55,940 binding in rat whole-brain membran...

  9. Central effects of the cannabinoid receptor agonist WIN55212-2 on respiratory and cardiovascular regulation in anaesthetised rats

    OpenAIRE

    Pfitzer, Torsten; Niederhoffer, Nathalie; Szabo, Bela

    2004-01-01

    The primary aim was to study the central respiratory effects of cannabinoids (CB). To this end, the cannabinoid receptor agonist WIN55212-2 was injected into the cisterna magna of urethane-anaesthetised rats and changes in respiratory parameters were observed. The secondary aim was to observe the centrally elicited cardiovascular actions of WIN55212-2. Involvement of opioid mechanisms in the central effects of WIN55212-2 was also studied.Intracisternal (i.c.) application of WIN55212-2 (1, 3, ...

  10. Modulation of breast cancer cell viability by a cannabinoid receptor 2 agonist, JWH-015, is calcium dependent

    Science.gov (United States)

    Hanlon, Katherine E; Lozano-Ondoua, Alysia N; Umaretiya, Puja J; Symons-Liguori, Ashley M; Chandramouli, Anupama; Moy, Jamie K; Kwass, William K; Mantyh, Patrick W; Nelson, Mark A; Vanderah, Todd W

    2016-01-01

    Introduction Cannabinoid compounds, both nonspecific as well as agonists selective for either cannabinoid receptor 1 (CB1) or cannabinoid receptor 2 (CB2), have been shown to modulate the tumor microenvironment by inducing apoptosis in tumor cells in several model systems. The mechanism of this modulation remains only partially delineated, and activity induced via the CB1 and CB2 receptors may be distinct despite significant sequence homology and structural similarity of ligands. Methods The CB2-selective agonist JWH-015 was used to investigate mechanisms downstream of CB2 activation in mouse and human breast cancer cell lines in vitro and in a murine mammary tumor model. Results JWH-015 treatment significantly reduced primary tumor burden and metastasis of luciferase-tagged murine mammary carcinoma 4T1 cells in immunocompetent mice in vivo. Furthermore, JWH-015 reduced the viability of murine 4T1 and human MCF7 mammary carcinoma cells in vitro by inducing apoptosis. JWH-015-mediated reduction of breast cancer cell viability was not dependent on Gαi signaling in vitro or modified by classical pharmacological blockade of CB1, GPR55, TRPV1, or TRPA1 receptors. JWH-015 effects were calcium dependent and induced changes in MAPK/ERK signaling. Conclusion The results of this work characterize the actions of a CB2-selective agonist on breast cancer cells in a syngeneic murine model representing how a clinical presentation of cancer progression and metastasis may be significantly modulated by a G-protein-coupled receptor. PMID:27186076

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

    OpenAIRE

    Pertwee, Roger G.

    2012-01-01

    Human tissues express cannabinoid CB1 and CB2 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 CB1/CB2 receptors are now in the clinic: Cesamet (nabilone), Marinol (dronabinol; Δ9-tetrahydrocannabinol (Δ9-THC)) and Sativex (Δ9-THC with cannabidiol). These can be presc...

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

    Energy Technology Data Exchange (ETDEWEB)

    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

  13. 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

  14. Cannabinoid CB1 receptor inverse agonists and neutral antagonists: Effects on food intake, food-reinforced behavior and food aversions

    OpenAIRE

    Salamone, John D.; McLaughlin, Peter J; Sink, Kelly; Makriyannis, Alexandros; Parker, Linda A

    2007-01-01

    Drugs that interfere with cannabinoid CB1 receptor transmission suppress a number of food-related behaviors, and these compounds are currently being assessed for their potential utility as appetite suppressants. In addition to rimonabant (SR141716A), several other compounds have been evaluated, including AM251 and AM1387. Biochemical studies indicate that most of the drugs assessed thus far have been CB1 inverse agonists, and these drugs all act to suppress food intake and disrupt food-reinfo...

  15. 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

  16. Involvement of PPAR receptors in the anticonvulsant effects of a cannabinoid agonist, WIN 55,212-2.

    Science.gov (United States)

    Payandemehr, Borna; Ebrahimi, Ali; Gholizadeh, Ramtin; Rahimian, Reza; Varastehmoradi, Bardia; Gooshe, Maziar; Aghaei, Hossein Nayeb; Mousavizadeh, Kazem; Dehpour, Ahmad Reza

    2015-03-01

    Cannabinoid and PPAR receptors show well established interactions in a set of physiological effects. Regarding the seizure-modulating properties of both classes of receptors, the present study aimed to evaluate the roles of the PPAR-gamma, PPAR-alpha and CB1 receptors on the anticonvulsant effects of WIN 55,212-2 (WIN, a non selective cannabinoid agonist). The clonic seizure thresholds after intravenous administration of pentylenetetrazole (PTZ) were assessed in mice weighing 23-30 g. WIN increased the seizure threshold dose dependently. Pretreatment with pioglitazone, as a PPARγ agonist, potentiated the anticonvulsant effects of WIN, while PPARγ antagonist inhibited these anticonvulsant effects partially. On the other hand PPARα antagonist reduced the anticonvulsant effects of WIN significantly. Finally the combination of CB1 antagonist and PPARα antagonist could completely block the anticonvulsant properties of WIN. Taken together, these results show for the first time that a functional interaction exists between cannabinoid and PPAR receptors in the modulation of seizure susceptibility. PMID:25448777

  17. 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

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

    Science.gov (United States)

    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

  19. Modulation of breast cancer cell viability by a cannabinoid receptor 2 agonist, JWH-015, is calcium dependent

    Directory of Open Access Journals (Sweden)

    Hanlon KE

    2016-04-01

    Full Text Available Katherine E Hanlon,1,2 Alysia N Lozano-Ondoua,1 Puja J Umaretiya,1 Ashley M Symons-Liguori,1 Anupama Chandramouli,1 Jamie K Moy,1 William K Kwass,1 Patrick W Mantyh,1 Mark A Nelson,3 Todd W Vanderah,11Department of Pharmacology, University of Arizona College of Medicine, Tucson, AZ, USA; 2Department of Biomedical Sciences, University of New England College of Osteopathic Medicine, Biddeford, ME, USA; 3Department of Pathology, University of Arizona College of Medicine, Tucson, AZ, USA Introduction: Cannabinoid compounds, both nonspecific as well as agonists selective for either cannabinoid receptor 1 (CB1 or cannabinoid receptor 2 (CB2, have been shown to modulate the tumor microenvironment by inducing apoptosis in tumor cells in several model systems. The mechanism of this modulation remains only partially delineated, and activity induced via the CB1 and CB2 receptors may be distinct despite significant sequence homology and structural similarity of ligands. Methods: The CB2-selective agonist JWH-015 was used to investigate mechanisms downstream of CB2 activation in mouse and human breast cancer cell lines in vitro and in a murine mammary tumor model. Results: JWH-015 treatment significantly reduced primary tumor burden and metastasis of luciferase-tagged murine mammary carcinoma 4T1 cells in immunocompetent mice in vivo. Furthermore, JWH-015 reduced the viability of murine 4T1 and human MCF7 mammary carcinoma cells in vitro by inducing apoptosis. JWH-015-mediated reduction of breast cancer cell viability was not dependent on Gαi signaling in vitro or modified by classical pharmacological blockade of CB1, GPR55, TRPV1, or TRPA1 receptors. JWH-015 effects were calcium dependent and induced changes in MAPK/ERK signaling. Conclusion: The results of this work characterize the actions of a CB2-selective agonist on breast cancer cells in a syngeneic murine model representing how a clinical presentation of cancer progression and metastasis may be

  20. 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

  1. Novel cannabinoid receptors

    OpenAIRE

    Brown, A J

    2007-01-01

    Cannabinoids have numerous physiological effects. In the years since the molecular identification of the G protein-coupled receptors CB1 and CB2, the ion channel TRPV1, and their corresponding endogenous ligand systems, many cannabinoid-evoked actions have been shown conclusively to be mediated by one of these specific receptor targets. However, there remain several examples where these classical cannabinoid receptors do not explain observed pharmacology. Studies using mice genetically delete...

  2. Effects of cannabinoid receptor agonists on neuronally-evoked contractions of urinary bladder tissues isolated from rat, mouse, pig, dog, monkey and human

    OpenAIRE

    Martin, R S; Luong, L A; Welsh, N. J.; Eglen, R. M.; Martin, G R; MacLennan, S J

    2000-01-01

    This study investigated the cannabinoid receptor, known to inhibit neuronally-evoked contractions of the mouse isolated urinary bladder, in bladder sections isolated from mouse, rat, dog, pig non-human primate or human.The CB1-like pharmacology of the cannabinoid receptor in mouse isolated bladder observed previously was confirmed in this study by the rank order of agonist potencies: CP 55940⩾WIN 55212-2>HU 210>JWH 015>anandamide, the high affinity of the CB1 selective antagonist, SR 141716A ...

  3. 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 ...

  4. 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...

  5. Cannabinoid receptor subtype 2 (CB2R) agonist, GW405833 reduces agonist-induced Ca2+ 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 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

  6. 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

  7. 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.

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

    OpenAIRE

    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; Artur M. S. Silva; Jagerovic, Nadine

    2012-01-01

    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 s...

  9. Cannabinoid Receptor Type 2 Agonist Attenuates Apoptosis by Activation of Phosphorylated CREB-Bcl-2 Pathway After Subarachnoid Hemorrhage in Rats

    OpenAIRE

    Fujii, Mutsumi; Sherchan, Prativa; Soejima, Yoshiteru; Hasegawa, Yu; Flores, Jerry; Doycheva, Desislava; Zhang, John H.

    2014-01-01

    Early brain injury (EBI) which comprises of vasogenic edema and apoptotic cell death is an important component of subarachnoid hemorrhage (SAH) pathophysiology. This study evaluated whether Cannabinoid receptor type 2 (CB2R) agonist, JWH133, attenuates EBI after SAH and whether CB2R stimulation reduces pro-apoptotic caspase-3 via up-regulation of cAMP response element-binding protein (CREB)-Bcl-2 signaling pathway. Male Sprague Dawley rats (n=123) were subjected to SAH by endovascular perfora...

  10. 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...

  11. Effects of CP 55,940 — agonist of CB1 cannabinoid receptors on ghrelin and somatostatin producing cells in the rat pancreas

    Directory of Open Access Journals (Sweden)

    Alicja Lewandowska

    2012-04-01

    Full Text Available Cannabinoids participate in the modulation of numerous functions in the human organism, increasing the sense of hunger, affecting carbohydrate and lipid metabolism, and controlling systemic energy balance mechanisms. Moreover, they influence the endocrine system functions, acting via two types of receptors, CB1 and CB2. The aim of the present study was to examine the number, distribution and activity of ghrelin and somatostatin producing endocrine cells in the pancreas of rats after a single administration of selective CP 55,940 agonist of CB1 receptor. The study was performed on 20 rats. Neuroendocrine cells were identified by immunohistochemical reactions, involving specific antibodies against ghrelin and somatostatin. The distribution and number of ghrelin- and somatostatin-immunoreactive cells were separately studied in five pancreas islets of each section. A performed analysis showed a decreased number of somatostatin-immunoreactive cells and a weak immunoreactivity of ghrelin and somatostatin containing neuroendocrine cells in the pancreatic islets of experimental rats, compared to control animals. The obtained results suggest that a single administration of a selective CP 55,940 agonist of CB1 receptor influences the immunoreactivity of endocrine cells with ghrelin and somatostatin expression in the pancreas islets.

  12. Similar anxiolytic effects of agonists targeting serotonin 5-HT1A or cannabinoid CB receptors on zebrafish behavior in novel environments.

    Science.gov (United States)

    Connors, Kristin A; Valenti, Theodore W; Lawless, Kelly; Sackerman, James; Onaivi, Emmanuel S; Brooks, Bryan W; Gould, Georgianna G

    2014-06-01

    The discovery that selective serotonin reuptake inhibitors (SSRIs) such as fluoxetine are present and bioaccumulate in aquatic ecosystems have spurred studies of fish serotonin transporters (SERTs) and changes in SSRI-sensitive behaviors as adverse outcomes relevant for risk assessment. Many SSRIs also act at serotonin 5-HT1A receptors. Since capitalizing on this action may improve treatments of clinical depression and other psychiatric disorders, novel multimodal drugs that agonize 5-HT1A and block SERT were introduced. In mammals both 5-HT1A and CB agonists, such as buspirone and WIN55,212-2, reduce anxious behaviors. Immunological and behavioral evidence suggests that 5-HT1A-like receptors may function similarly in zebrafish (Danio rerio), yet their pharmacological properties are not well characterized. Herein we compared the density of [(3)H] 8-hydroxy-2-di-n-propylamino tetralin (8-OH-DPAT) binding to 5-HT1A-like sites in the zebrafish brain, to that of similarly Gαi/o-coupled cannabinoid receptors. [(3)H] 8-OH-DPAT specific binding was 176±8, 275±32, and 230±36fmol/mg protein in the hypothalamus, optic tectum, and telencephalon. [(3)H] WIN55,212-2 binding density was higher in those same brain regions at 6±0.3, 5.5±0.4 and 7.3±0.3pm/mg protein. The aquatic light-dark plus maze was used to examine behavioral effects of 5-HT1A and CB receptor agonists on zebrafish novelty-based anxiety. With acute exposure to the 5-HT1A partial-agonist buspirone (50mg/L), or dietary exposure to WIN55,212-2 (7μg/week) zebrafish spent more time in and/or entered white arms more often than controls (pecological risks of azapirones and multimodal antidepressants in the future. PMID:24411165

  13. 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.

  14. 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.

  15. 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.

  16. 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 ...

  17. G-protein coupling of cannabinoid receptors

    International Nuclear Information System (INIS)

    Full text: Since the cloning of the cannabinoid CB1 and CB2 receptors in the early 1990's extensive research has focused on understanding their signal transduction pathways. While it has been known for sometime that both receptors can couple to intracellular signalling via pertussis toxin sensitive G-proteins (Gi/Go), the specificity and kinetics of these interactions have only recently been elucidated. We have developed an in situ reconstitution approach to investigating receptor-G-protein interactions. This approach involves chaotropic extraction of receptor containing membranes in order to inactivate or remove endogenous G-proteins. Recombinant or isolated brain G-proteins can then be added back to the receptors, and their activation monitored through the binding of [35S]-GTPγS. This technique has been utilised for an extensive study of cannabinoid receptor mediated activation of G-proteins. In these studies we have established that CB1 couples with high affinity to both Gi and Go type G-proteins. In contrast, CB2 couples strongly to Gi, but has a very low affinity for Go. This finding correlated well with the previous findings that while CB1 and CB2 both couple to the inhibition of adenylate cyclase, CB1 but not CB2 could also inhibit calcium channels. We then examined the ability of a range of cannabinoid agonists to activate the Gi and Go via CB1. Conventional receptor theory suggests that a receptor is either active or inactive with regard to a G-protein and that the active receptor activates all relevant G-proteins equally. However, in this study we found that agonists could produce different degrees of activation, depending on which G-protein was present. Further studies have compared the ability of the two endocannabinoids to drive the activation of Gi or Go. These studies show that agonists can induce multiple forms of activated receptor that differ in their ability to catalyse the activation of Gi or Go. The ability of an agonist to drive a receptor

  18. 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...

  19. 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.

  20. Cannabinoid-induced mesenteric vasodilation through an endothelial site distinct from CB1 or CB2 receptors

    OpenAIRE

    Járai, Zoltán; Wagner, Jens A.; Varga, Károly; Lake, Kristy D.; Compton, David R.; Martin, Billy R.; Zimmer, Anne M.; Bonner, Tom I.; Buckley, Nancy E.; Mezey, Eva; Razdan, Raj K; Zimmer, Andreas; Kunos, George

    1999-01-01

    Cannabinoids, including the endogenous ligand arachidonyl ethanolamide (anandamide), elicit not only neurobehavioral but also cardiovascular effects. Two cannabinoid receptors, CB1 and CB2, have been cloned, and studies with the selective CB1 receptor antagonist SR141716A have implicated peripherally located CB1 receptors in the hypotensive action of cannabinoids. In rat mesenteric arteries, anandamide-induced vasodilation is inhibited by SR141716A, but other potent CB1 receptor agonists, suc...

  1. 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

  2. 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

  3. Identification of Essential Cannabinoid-binding Domains: STRUCTURAL INSIGHTS INTO EARLY DYNAMIC EVENTS IN RECEPTOR ACTIVATION*

    OpenAIRE

    Shim, Joong-Youn; Bertalovitz, Alexander C.; Kendall, Debra A.

    2011-01-01

    The classical cannabinoid agonist HU210, a structural analog of (−)-Δ9-tetrahydrocannabinol, binds to brain cannabinoid (CB1) receptors and activates signal transduction pathways. To date, an exact molecular description of the CB1 receptor is not yet available. Utilizing the minor binding pocket of the CB1 receptor as the primary ligand interaction site, we explored HU210 binding using lipid bilayer molecular dynamics (MD) simulations. Among the potential ligand contact residues, we identifie...

  4. The cannabinoid agonist WIN55,212-2 increases intracellular calcium via CB1 receptor coupling to Gq/11 G proteins

    OpenAIRE

    Lauckner, Jane E.; Hille, Bertil; Mackie, Ken

    2005-01-01

    Central nervous system responses to cannabis are primarily mediated by CB1 receptors, which couple preferentially to Gi/o G proteins. Here, we used calcium photometry to monitor the effect of CB1 activation on intracellular calcium concentration. Perfusion with 5 μM CB1 aminoalkylindole agonist, WIN55,212-2 (WIN), increased intracellular calcium by several hundred nanomolar in human embryonic kidney 293 cells stably expressing CB1 and in cultured hippocampal neurons. The increase was blocked ...

  5. 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.

  6. 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 ...

  7. 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

  8. 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

  9. Functional role of cannabinoid receptors in urinary bladder

    OpenAIRE

    Tyagi, Pradeep; Tyagi, Vikas; Yoshimura, Naoki; Chancellor, Michael

    2010-01-01

    Cannabinoids, the active components of Cannabis sativa (maijuana), and their derivatives produce a wide spectrum of central and peripheral effects, some of which may have clinical applications. The discovery of specific cannabinoid receptors and a family of endogenous ligands of those receptors has attracted much attention to the general cannabinoid pharmacology. In recent years, studies on the functional role of cannabinoid receptors in bladder have been motivated by the therapeutic effects ...

  10. Cannabinoid receptor 2: potential role in immunomodulation and neuroinflammation.

    Science.gov (United States)

    Rom, Slava; Persidsky, Yuri

    2013-06-01

    An accumulating body of evidence suggests that endocannabinoids and cannabinoid receptors type 1 and 2 (CB(1), CB(2)) play a significant role in physiologic and pathologic processes, including cognitive and immune functions. While the addictive properties of marijuana, an extract from the Cannabis plant, are well recognized, there is growing appreciation of the therapeutic potential of cannabinoids in multiple pathologic conditions involving chronic inflammation (inflammatory bowel disease, arthritis, autoimmune disorders, multiple sclerosis, HIV-1 infection, stroke, Alzheimer's disease to name a few), mainly mediated by CB(2) activation. Development of CB(2) agonists as therapeutic agents has been hampered by the complexity of their intracellular signaling, relative paucity of highly selective compounds and insufficient data regarding end effects in the target cells and organs. This review attempts to summarize recent advances in studies of CB(2) activation in the setting of neuroinflammation, immunomodulation and HIV-1 infection. PMID:23471521

  11. 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

    New types of synthetic cannabinoid designer drugs are constantly introduced to the illicit drug market to circumvent legislation. Recently, N-​(1-Adamant​yl)-​1-​(5-​fluoropentyl)-​1H-​indazole-​3-​carboxamide (5F-AKB-48), also known as 5F-APINACA, was identified as an adulterant in herbal products...

  12. Distribution of CB1 Cannabinoid Receptors and Their Relationship with Mu-Opioid Receptors in the Rat Periaqueductal Gray

    OpenAIRE

    Wilson-Poe, A R; Morgan, M.M.; Aicher, S.A.; Hegarty, D.M.

    2012-01-01

    The periaqueductal gray (PAG) is part of a descending pain modulatory system that, when activated, produces widespread and profound antinociception. Microinjection of either opioids or cannabinoids into the PAG elicits antinociception. Moreover, microinjection of the cannabinoid 1 (CB1) receptor agonist HU-210 into the PAG enhances the antinociceptive effect of subsequent morphine injections, indicating a direct relationship between these two systems. The objective of this study was to charac...

  13. Cannabinoid receptor CB2 modulates axon guidance

    DEFF Research Database (Denmark)

    Duff, Gabriel; Argaw, Anteneh; Cecyre, Bruno; Cherif, Hosni; Tea, Nicolas; Zabouri, Nawal; Casanova, Christian; Ptito, Maurice; Bouchard, Jean-François

    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 ...

  14. 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

  15. Cannabinoids promote oligodendrocyte progenitor survival: Involvement of cannabinoid receptors and phosphatidylinositol-3 kinase/Akt signaling

    OpenAIRE

    Molina-Holgado, E; Vela, J.M. (José Miguel); Arévalo, Maria Ángeles; Almazán, G.; Molina-Holgado, F.; Borrell, Jose; Guaza, Carmen

    2002-01-01

    Cannabinoids exert pleiotropic actions in the CNS, including the inhibition of inflammatory responses and the enhancement of neuronal survival after injury. Although cannabinoid receptors are distributed widely in brain, their presence has not been investigated previously in oligodendrocytes. This study examined the expression of cannabinoid type 1 (CB1) receptors in rat oligodendrocytes in vivo and in culture and explored their biological function. Expression of CB1 receptors by oligodendroc...

  16. Cannabinoid receptor type-1: breaking the dogmas

    Science.gov (United States)

    Busquets Garcia, Arnau; Soria-Gomez, Edgar; Bellocchio, Luigi; Marsicano, Giovanni

    2016-01-01

    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 (CB 1). 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 CB 1 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 CB 1 receptor structure led researchers to propose interesting and new allosteric modulators. Thus, the advances and the new directions of the CB 1 receptor field will provide new insights and better approaches to profit from its interesting therapeutic profile.

  17. Cannabinoid receptor 1 is a potential drug target for treatment of translocation-positive rhabdomyosarcoma.

    Science.gov (United States)

    Oesch, Susanne; Walter, Dagmar; Wachtel, Marco; Pretre, Kathya; Salazar, Maria; Guzmán, Manuel; Velasco, Guillermo; Schäfer, Beat W

    2009-07-01

    Gene expression profiling has revealed that the gene coding for cannabinoid receptor 1 (CB1) is highly up-regulated in rhabdomyosarcoma biopsies bearing the typical chromosomal translocations PAX3/FKHR or PAX7/FKHR. Because cannabinoid receptor agonists are capable of reducing proliferation and inducing apoptosis in diverse cancer cells such as glioma, breast cancer, and melanoma, we evaluated whether CB1 is a potential drug target in rhabdomyosarcoma. Our study shows that treatment with the cannabinoid receptor agonists HU210 and Delta(9)-tetrahydrocannabinol lowers the viability of translocation-positive rhabdomyosarcoma cells through the induction of apoptosis. This effect relies on inhibition of AKT signaling and induction of the stress-associated transcription factor p8 because small interfering RNA-mediated down-regulation of p8 rescued cell viability upon cannabinoid treatment. Finally, treatment of xenografts with HU210 led to a significant suppression of tumor growth in vivo. These results support the notion that cannabinoid receptor agonists could represent a novel targeted approach for treatment of translocation-positive rhabdomyosarcoma. PMID:19509271

  18. CB2 Cannabinoid Receptor As Potential Target against Alzheimer's Disease

    Science.gov (United States)

    Aso, Ester; Ferrer, Isidro

    2016-01-01

    The CB2 receptor is one of the components of the endogenous cannabinoid system, a complex network of signaling molecules and receptors involved in the homeostatic control of several physiological functions. Accumulated evidence suggests a role for CB2 receptors in Alzheimer's disease (AD) and indicates their potential as a therapeutic target against this neurodegenerative disease. Levels of CB2 receptors are significantly increased in post-mortem AD brains, mainly in microglia surrounding senile plaques, and their expression levels correlate with the amounts of Aβ42 and β-amyloid plaque deposition. Moreover, several studies on animal models of AD have demonstrated that specific CB2 receptor agonists, which are devoid of psychoactive effects, reduce AD-like pathology, resulting in attenuation of the inflammation associated with the disease but also modulating Aβ and tau aberrant processing, among other effects. CB2 receptor activation also improves cognitive impairment in animal models of AD. This review discusses available data regarding the role of CB2 receptors in AD and the potential usefulness of specific agonists of these receptors against AD. PMID:27303261

  19. 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

  20. GPR55: a new member of the cannabinoid receptor clan?

    OpenAIRE

    Pertwee, R. G.

    2007-01-01

    In this issue of the British Journal of Pharmacology, Ryberg et al. present convincing in vitro evidence that the orphan GPCR, GPR55, is a cannabinoid receptor. GPR55 was activated by a range of plant, synthetic and endogenous cannabinoids and blocked by the non-psychoactive phytocannabinoid, cannabidiol. Their experiments have revealed several differences between the pharmacology of GPR55 and the established cannabinoid CB1 and CB2 receptors. For example, the CB1 receptor antagonist, AM251, ...

  1. Involvement of cannabinoid-1 and cannabinoid-2 receptors in septic ileus.

    Science.gov (United States)

    Li, Y-Y; Li, Y-N; Ni, J-B; Chen, C-J; Lv, S; Chai, S-Y; Wu, R-H; Yüce, B; Storr, M

    2010-03-01

    BACKGROUND Cannabinoid (CB) receptors are involved in the regulation of gastrointestinal (GI) motility under physiological and pathophysiological conditions. We aimed to characterize the possible influence of CB(1) and CB(2) receptors on motility impairment in a model of septic ileus. METHODS Lipopolysaccharide (LPS) injections were used to mimic pathophysiological features of septic ileus. Spontaneous jejunal myoelectrical activity was measured in rats in vivo, and upper GI transit was measured in vivo by gavaging of a charcoal marker into the stomach of mice, in absence or presence of LPS, and CB(1) and CB(2) receptor agonists and antagonists. Tumour necrosis factor (TNF)-alpha and interleukin (IL)-6 levels were measured using enzyme-linked immunosorbent assay. Histology was performed with haematoxylin-eosin staining. KEY RESULTS Lipopolysaccharide treatment significantly reduced amplitude and frequency of myoelectric spiking activity and GI transit in vivo in a dose-dependent manner. TNF-alpha and IL-6 were increased in LPS-treated animals and histology showed oedema and cell infiltration. Both, the CB(1) agonist HU210 and the CB(2) agonist JWH133 reduced myoelectrical activity whereas the CB(1) antagonist AM251 caused an increase of myoelectrical activity. Pretreatment with AM251 or AM630 prevented against LPS-induced reduction of myoelectrical activity, and also against the delay of GI transit during septic ileus in vivo. CONCLUSIONS & INFERENCES The LPS model of septic ileus impairs jejunal myoelectrical activity and delays GI transit in vivo. Antagonists at the CB(1) receptor or the CB(2) receptor prevent the delay of GI transit and thus may be powerful tools in the future treatment of septic ileus. PMID:19840270

  2. 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; Benetti, Veronica; Ligresti, Alessia; Cascio, Maria Grazia; Tuccinardi, Tiziano; Lucchesi, Valentina; Martinelli, Adriano; Nieri, Paola; Masini, Emanuela; Di Marzo, Vincenzo; Ferrarini, Pier Luigi

    2009-01-01

    revealed that compound 12, which presented benzyl and carboxy-4-methylcyclohexylamide substituents bound in the 1 and 3 positions, exerted a CB(2)-mediated inhibitory action on immunological human basophil activation. On the human T cell leukemia line Jurkat the same derivative induced a concentration......-dependent decrease of cell viability. The obtained results suggest that 1,8-naphthyridin-2(1H)-on-3-carboxamides represent a new scaffold very suitable for the development of new promising CB(2) agonists....

  3. CB1 cannabinoid receptor stimulation modulates transient receptor potential vanilloid receptor 1 activities in calcium influx and substande P release in cultured rat dorsal root ganglion cells

    OpenAIRE

    Ohshita, Kyoko

    2005-01-01

    Cannabinoids have been reported to have analgesic properties in animals of acute nociception or of inflammatory and neuropathic pain models, but the mechanisms by which they exert such alleviative effects are not yet fully understood. We investigated whether the CB1- cannabinoid-receptor agonist HU210 modulates the capsaicin-induced 45Ca2+ influx and substance P like-immunoreactivity (SPLI) release in cultured rat dorsal root ganglion (DRG) cells. HU210 attenuated the capsaicin-induced 45Ca2+...

  4. 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

  5. Local activation of cannabinoid CB1 receptors in the urinary bladder reduces the inflammation-induced sensitization of bladder afferents

    Directory of Open Access Journals (Sweden)

    Cervero Fernando

    2011-05-01

    Full Text Available Abstract Background Systemic administration of cannabinoid agonists is known to reduce pain induced by bladder inflammation and to modulate cystometric parameters in vivo. We have previously reported that intravesical administration of a cannabinoid agonist reduces the electrical activity of bladder afferents under normal conditions. However, the effects of local activation of bladder cannabinoid receptors on afferent activity during inflammation are unknown. This study was aimed to assess the effects of intravesical administration of a cannabinoid agonist on the discharges of afferent fibers in inflamed bladders ex vivo. We also characterized the expression of CB1 receptors in the bladder and their localization and co-expression with TRPV1, a marker of nociceptive afferents. Results Compared to untreated animals, afferent fiber activity in inflamed bladders was increased for intravesical pressures between 10 and 40 mmHg. Local treatment with a non selective cannabinoid agonist (AZ12646915 significantly reduced the afferent activity at intravesical pressures above 20 mmHg. This effect was blocked by AM251 but not by AM630 (selective for CB1 and CB2 respectively. Finally, CB1 was co-expressed with TRPV1 in control and inflamed bladders. Conclusion These results demonstrate that sensitization of bladder afferents induced by inflammation is partly suppressed by intravesical activation of cannabinoid receptors, an effect that appears to be mediated by CB1 receptors. Also, TRPV1 positive fibers were found to co-express CB1, supporting the hypothesis of a direct action of the cannabinoid agonist on nociceptive afferents. Taken together, these results indicate a peripheral modulation by the cannabinoid system of bladder hypersensitivity during inflammation.

  6. 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.

  7. 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

  8. Identification of essential cannabinoid-binding domains: structural insights into early dynamic events in receptor activation.

    Science.gov (United States)

    Shim, Joong-Youn; Bertalovitz, Alexander C; Kendall, Debra A

    2011-09-23

    The classical cannabinoid agonist HU210, a structural analog of (-)-Δ(9)-tetrahydrocannabinol, binds to brain cannabinoid (CB1) receptors and activates signal transduction pathways. To date, an exact molecular description of the CB1 receptor is not yet available. Utilizing the minor binding pocket of the CB1 receptor as the primary ligand interaction site, we explored HU210 binding using lipid bilayer molecular dynamics (MD) simulations. Among the potential ligand contact residues, we identified residues Phe-174(2.61), Phe-177(2.64), Leu-193(3.29), and Met-363(6.55) as being critical for HU210 binding by mutational analysis. Using these residues to guide the simulations, we determined essential cannabinoid-binding domains in the CB1 receptor, including the highly sought after hydrophobic pocket important for the binding of the C3 alkyl chain of classical and nonclassical cannabinoids. Analyzing the simulations of the HU210-CB1 receptor complex, the CP55940-CB1 receptor complex, and the (-)-Δ(9)-tetrahydrocannabinol-CB1 receptor complex, we found that the positioning of the C3 alkyl chain and the aromatic stacking between Trp-356(6.48) and Trp-279(5.43) is crucial for the Trp-356(6.48) rotamer change toward receptor activation through the rigid-body movement of H6. The functional data for the mutant receptors demonstrated reductions in potency for G protein activation similar to the reductions seen in ligand binding affinity for HU210. PMID:21795705

  9. 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...

  10. A synthetic cannabinoid agonist promotes oligodendrogliogenesis during viral encephalitis in rats

    OpenAIRE

    Solbrig, Marylou V.; Fan, Yijun; Hermanowicz, Neal; Morgese, Maria Grazia; Giuffrida, Andrea

    2010-01-01

    Chronic CNS infection by several families of viruses can produce deficits in prefrontal cortex (PFC) and striatal function. Cannabinoid drugs have been long known for their anti-inflammatory properties and their ability to modulate adult neuro and gliogenesis. Therefore, we explored the effects of systemic administration of the cannabinoid agonist WIN55,212-2(WIN) on prefrontal cortex(PFC) and striatal cytogenesis in a viral model of CNS injury and inflammation based on Borna Disease (BD) vir...

  11. 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...

  12. The cannabinoid agonist HU-210: pseudo-irreversible discriminative stimulus effects in rhesus monkeys

    OpenAIRE

    Hruba, Lenka; McMahon, Lance R.

    2014-01-01

    Synthetic cannabinoid abuse and case reports of adverse effects have raised concerns about the pharmacologic mechanisms underlying in vivo effects. Here, a synthetic cannabinoid identified in abused products (HU-210) was compared to the effects of Δ9-THC and two other synthetic cannabinoid agonists used extensively in pre-clinical studies (CP 55,940 and WIN 55,212-2). One group of monkeys discriminated Δ9-THC (0.1 mg/kg i.v.); a separate group received chronic Δ9-THC (1 mg/kg/12 h s.c.) and d...

  13. Ligand Binding Sensitivity of the Extracellular Loop Two of the Cannabinoid Receptor 1

    OpenAIRE

    Bertalovitz, Alexander C.; Ahn, Kwang H.; Kendall, Debra A.

    2010-01-01

    The cannabinoid receptor one (CB1) is a class A G-protein-coupled receptor thought to bind ligands primarily within its helical bundle. Evidence suggests, however, that the extracellular domain may also play a role. We have previously shown that the C-terminus of the extracellular loop 2 of CB1 is important in binding some compounds; receptors with mutations in this region (F268W, P269A, H270A, and I271A) bound some agonists with severely reduced affinity relative to the wild-type receptor. I...

  14. Contrasting effects of different cannabinoid receptor ligands on mouse ingestive behaviour.

    Science.gov (United States)

    Grey, Jonathan; Terry, Phil; Higgs, Suzanne

    2012-09-01

    This study characterized the effects of seven diverse cannabinoid receptor agonists (and one antagonist) on ingestive behaviour in nondeprived adult, male CD1 mice. Microstructural analysis of licking for a range of concentrations of condensed milk (10, 15 and 20%) was carried out following administration of vehicle or: Δ⁹-tetrahydrocannabinol (Δ⁹-THC) at 1, 3 or 6 mg/kg; CP55,940 at 10, 30 or 50 µg/kg; Win 55,212-2 at 0.5, 1 or 3 mg/kg; HU-210 at 0.01, 0.03 or 0.1 mg/kg; methanandamide at 1, 3 or 6 mg/kg; arachidonyl-2'-chloroethylamide at 1, 3 or 6 mg/kg and JWH133 at 1, 3 or 6 mg/kg. The cannabinoid receptor antagonist/inverse agonist rimonabant was also tested at 0.3, 1 or 3 mg/kg. Test sessions comprised three 30 s presentations of the milk concentrations separated by 10 s interpresentation intervals. The nonselective CB1 receptor agonists Δ⁹-THC, CP55,940 and Win 55,212-2 increased the number of licks for condensed milk, primarily by a significant increase in bout number. The potent and nonselective CB1 receptor agonist HU-210 and the selective CB1 receptor agonists methanandamide and arachidonyl-2'-chloroethylamide did not significantly affect licking behaviour but did significantly increase the latency to start licking. The CB1 receptor antagonist rimonabant produced effects that were opposite in direction to those produced by Δ⁹-THC, CP55,940 and Win 55,212-2. Finally, the selective CB2 receptor agonist JWH133 had no significant effects on behaviour. These data add to reports that cannabinoid agonists can enhance the appetitive aspects of feeding, but they also demonstrate that not all CB1 receptor agonists do this, and therefore the relationship between action at CB1 receptors and appetitive feeding effects is not straightforward. PMID:22772336

  15. 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

  16. Cannabinoid receptor activation reverses kainate-induced synchronized population burst firing in rat hippocampus

    Directory of Open Access Journals (Sweden)

    Rob Mason

    2009-06-01

    Full Text Available Cannabinoids have been shown to possess anticonvulsant properties in whole animal models of epilepsy. The present investigation sought to examine the effects of cannabinoid receptor activation on kainic acid (KA-induced epileptiform neuronal excitability. Under urethane anesthesia, acute KA treatment (10 mg/kg, i.p. entrained the spiking mode of simultaneously recorded neurons from random firing to synchronous bursting (% change in burst rate. Injection of the high-affinity cannabinoid agonist (--11-hydroxy-8-tetrahydrocannabinol-dimethyl-heptyl (HU210, 100 µg/kg, i.p. following KA markedly reduced the burst frequency (% decrease in burst frequency and reversed synchronized firing patterns back to baseline levels. Pre-treatment with the central cannabinoid receptor (CB1 antagonist N-piperidino-5-(4-clorophenyl-1-(2,4-dichlorophenyl-4-methyl-3-pyrazole-carboxamide (rimonabant, SR141716A 3 mg/kg, i.p. completely prevented the actions of HU210. The present results indicate that cannabinoids exert their antiepileptic effects by impeding pathological synchronization of neuronal networks in the hippocampus.

  17. Cannabinoid receptor activation reverses kainate-induced synchronized population burst firing in rat hippocampus.

    Science.gov (United States)

    Mason, Rob; Cheer, Joseph F

    2009-01-01

    Cannabinoids have been shown to possess anticonvulsant properties in whole animal models of epilepsy. The present investigation sought to examine the effects of cannabinoid receptor activation on kainic acid (KA)-induced epileptiform neuronal excitability. Under urethane anesthesia, acute KA treatment (10 mg kg(-1), i.p.) entrained the spiking mode of simultaneously recorded neurons from random firing to synchronous bursting (% change in burst rate). Injection of the high-affinity cannabinoid agonist (-)-11-hydroxy-8-tetrahydrocannabinol-dimethyl-heptyl (HU210, 100 mug kg(-1), i.p.) following KA markedly reduced the burst frequency (% decrease in burst frequency) and reversed synchronized firing patterns back to baseline levels. Pre-treatment with the central cannabinoid receptor (CB1) antagonist N-piperidino-5-(4-clorophenyl)-1-(2,4-dichlorophenyl)-4-methyl-3-pyrazole-carboxamide (rimonabant, SR141716A 3 mg kg(-1), i.p.) completely prevented the actions of HU210. The present results indicate that cannabinoids exert their antiepileptic effects by impeding pathological synchronization of neuronal networks in the hippocampus. PMID:19562087

  18. 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

  19. 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

  20. Cannabinoid receptor type 1 protects nigrostriatal dopaminergic neurons against MPTP neurotoxicity by inhibiting microglial activation.

    Science.gov (United States)

    Chung, Young C; Bok, Eugene; Huh, Sue H; Park, Ju-Young; Yoon, Sung-Hwa; Kim, Sang R; Kim, Yoon-Seong; Maeng, Sungho; Park, Sung Hyun; Jin, Byung K

    2011-12-15

    This study examined whether the cannabinoid receptor type 1 (CB(1)) receptor contributes to the survival of nigrostriatal dopaminergic (DA) neurons in the 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) mouse model of Parkinson's disease. MPTP induced significant loss of nigrostriatal DA neurons and microglial activation in the substantia nigra (SN), visualized with tyrosine hydroxylase or macrophage Ag complex-1 immunohistochemistry. Real-time PCR, ELISA, Western blotting, and immunohistochemistry disclosed upregulation of proinflammatory cytokines, activation of microglial NADPH oxidase, and subsequent reactive oxygen species production and oxidative damage of DNA and proteins in MPTP-treated SN, resulting in degeneration of DA neurons. Conversely, treatment with nonselective cannabinoid receptor agonists (WIN55,212-2 and HU210) led to increased survival of DA neurons in the SN, their fibers and dopamine levels in the striatum, and improved motor function. This neuroprotection by cannabinoids was accompanied by suppression of NADPH oxidase reactive oxygen species production and reduced expression of proinflammatory cytokines from activated microglia. Interestingly, cannabinoids protected DA neurons against 1-methyl-4-phenyl-pyridinium neurotoxicity in cocultures of mesencephalic neurons and microglia, but not in neuron-enriched mesencephalic cultures devoid of microglia. The observed neuroprotection and inhibition of microglial activation were reversed upon treatment with CB(1) receptor selective antagonists AM251 and/or SR14,716A, confirming the involvement of the CB(1) receptor. The present in vivo and in vitro findings clearly indicate that the CB(1) receptor possesses anti-inflammatory properties and inhibits microglia-mediated oxidative stress. Our results collectively suggest that the cannabinoid system is beneficial for the treatment of Parkinson's disease and other disorders associated with neuroinflammation and microglia-derived oxidative damage

  1. A runner's high depends on cannabinoid receptors in mice.

    Science.gov (United States)

    Fuss, Johannes; Steinle, Jörg; Bindila, Laura; Auer, Matthias K; Kirchherr, Hartmut; Lutz, Beat; Gass, Peter

    2015-10-20

    Exercise is rewarding, and long-distance runners have described a runner's high as a sudden pleasant feeling of euphoria, anxiolysis, sedation, and analgesia. A popular belief has been that endogenous endorphins mediate these beneficial effects. However, running exercise increases blood levels of both β-endorphin (an opioid) and anandamide (an endocannabinoid). Using a combination of pharmacologic, molecular genetic, and behavioral studies in mice, we demonstrate that cannabinoid receptors mediate acute anxiolysis and analgesia after running. We show that anxiolysis depends on intact cannabinoid receptor 1 (CB1) receptors on forebrain GABAergic neurons and pain reduction on activation of peripheral CB1 and CB2 receptors. We thus demonstrate that the endocannabinoid system is crucial for two main aspects of a runner's high. Sedation, in contrast, was not influenced by cannabinoid or opioid receptor blockage, and euphoria cannot be studied in mouse models. PMID:26438875

  2. Cannabinoid receptor 2: Potential role in immunomodulation and neuroinflammation Review

    OpenAIRE

    Rom, Slava; Persidsky, Yuri

    2013-01-01

    An accumulating body of evidence suggests that endocannabinoids and cannabinoid receptors type 1 and 2 (CB1, CB2) play a significant role in physiologic and pathologic processes, including cognitive and immune functions. While the addictive properties of marijuana, an extract from the Cannabis plant, are well recognized, there is growing appreciation of the therapeutic potential of cannabinoids in multiple pathologic conditions involving chronic inflammation (inflammatory bowel disease, arthr...

  3. 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...

  4. Gastric antisecretory role and immunohistochemical localization of cannabinoid receptors in the rat stomach

    OpenAIRE

    Adami, Maristella; Frati, Paolo; Bertini, Simone; Kulkarni-Narla, Anjali; Brown, David R; Caro, Giuseppe de; Coruzzi, Gabriella; Soldani, Giulio

    2002-01-01

    The role of cannabinoid (CB) receptors in the regulation of gastric acid secretion was investigated in the rat by means of functional experiments and by immunohistochemistry.In anaesthetized rats with lumen-perfused stomach, the non selective CB-receptor agonist WIN 55,212-2 (0.30 – 4.00 μmol kg−1, i.v.) and the selective CB1-receptor agonist HU-210 (0.03 – 1.50 μmol kg−1, i.v.), dose-dependently decreased the acid secretion induced by both pentagastrin (30 nmol kg−1 h−1) and 2-deoxy-D-glucos...

  5. Identification of a Functionally Relevant Cannabinoid Receptor on Mouse Spleen Cells that Is Involved in Cannabinoid-Mediated Immune Modulation

    OpenAIRE

    Kaminski, Norbert E.; Abood, Mary E.; Kessler, Fay K.; Martin, Billy R.; Schatz, Anthony R.

    1992-01-01

    Extensive behavioral and biochemical characterization of cannabinoid-mediated effects on the central nervous system has revealed at least three lines of evidence supporting the role of a putative guanine nucleotide-binding protein-coupled cannabinoid receptor for cannabimimetic effects, (i) stereoselectivity, (ii) inhibition of the adenylate cyclase/cAMP second messenger system, and (iii) radioligand-binding studies with the synthetic cannabinoid [3H]CP-55,940 indicating a high degree of spec...

  6. Thrombopoietin Receptor Agonists in Primary ITP

    OpenAIRE

    Siegal, Deborah; Crowther, Mark; Cuker, Adam

    2013-01-01

    Thrombopoietin (TPO) regulates thrombopoiesis through activation of TPO receptors on the megakaryocyte cell surface, resulting in increased platelet production. The TPO receptor agonists are novel treatments for patients with chronic ITP aimed at increasing platelet production through interactions with the TPO receptor on megakaryocytes. Two TPO receptor agonists, romiplostim and eltrombopag, have received regulatory approval. In patients with chronic ITP who remain at risk of bleeding follow...

  7. HU210-induced downregulation in cannabinoid CB1 receptor binding strongly correlates with body weight loss in the adult rat.

    Science.gov (United States)

    Dalton, Victoria S; Wang, Hongqin; Zavitsanou, Katerina

    2009-07-01

    In vitro autoradiography was used to examine changes in cannabinoid CB1 receptors (targeted with [(3)H] CP55,940) in rats treated with the potent cannabinoid agonist HU210. Animals were administered with HU210 (25, 50, 100 microg/kg) for 4 or 14 days or received a single 100 microg/kg injection of HU210 and sacrificed 24 h later. The acute dose resulted in a decrease in binding in the caudate putamen and hippocampus. A dose dependent, region-specific reduction (P HU210. PMID:19169813

  8. Cannabinoids go nuclear: evidence for activation of peroxisome proliferator-activated receptors

    OpenAIRE

    O'Sullivan, S E

    2007-01-01

    Cannabinoids act at two classical cannabinoid receptors (CB1 and CB2), a 7TM orphan receptor and the transmitter-gated channel transient receptor potential vanilloid type-1 receptor. Recent evidence also points to cannabinoids acting at members of the nuclear receptor family, peroxisome proliferator-activated receptors (PPARs, with three subtypes α, β (δ) and γ), which regulate cell differentiation and lipid metabolism. Much evidence now suggests that endocannabinoids are natural activators o...

  9. 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

  10. 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

  11. 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

  12. 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

  13. 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), ...

  14. Emerging GLP-1 receptor agonists

    DEFF Research Database (Denmark)

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

    2011-01-01

    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 system and cyclooxygenases inhibitors

    OpenAIRE

    Păunescu, H; Coman, OA; Coman, L.; Ghiţă, I; Georgescu, SR; Drăia, F; Fulga, I

    2011-01-01

    Rationale. The cannabinoid system consists of a complex array of receptors, substances with agonist/antagonist properties for those receptors, biosynthetic machineries and mechanisms for cellular uptake and degradation for endocannabinoids. This system is in interrelation with other systems that comprise lipid mediators like prostaglandins/leukotrienes systems. A clear antagonist, additive or synergic effect of nonsteroidal anti–inflammatory drugs (NSAIDs)–cannabinoid associations was not yet...

  16. CB1 cannabinoid receptor antagonism promotes remodeling and cannabinoid treatment prevents endothelial dysfunction and hypotension in rats with myocardial infarction

    OpenAIRE

    Wagner, Jens A.; Hu, Kai; Karcher, Jan; Bauersachs, Johann; Schäfer, Andreas; Laser, Martin; Han, Hong; Ertl, Georg

    2003-01-01

    To study the long-term effects of altered cannabinoid receptor activity on myocardial and vascular function, Wistar rats were treated with the selective CB1 antagonist AM-251 (0.5 mg kg−1 d−1), the potent synthetic cannabinoid HU-210 (50 μg kg−1 d−1) or vehicle for 12 weeks after coronary artery ligation or sham operation.AM-251 further reduced the pressure-generating capacity, shifted the pressure volume curve to the right (P

  17. Cytotoxicity of synthetic cannabinoids on primary neuronal cells of the forebrain: the involvement of cannabinoid CB{sub 1} receptors and apoptotic cell death

    Energy Technology Data Exchange (ETDEWEB)

    Tomiyama, Ken-ichi; Funada, Masahiko, E-mail: mfunada@ncnp.go.jp

    2014-01-01

    The abuse of herbal products containing synthetic cannabinoids has become an issue of public concern. The purpose of this paper was to evaluate the acute cytotoxicity of synthetic cannabinoids on mouse brain neuronal cells. Cytotoxicity induced by synthetic cannabinoid (CP-55,940, CP-47,497, CP-47,497-C8, HU-210, JWH-018, JWH-210, AM-2201, and MAM-2201) was examined using forebrain neuronal cultures. These synthetic cannabinoids induced cytotoxicity in the forebrain cultures in a concentration-dependent manner. The cytotoxicity was suppressed by preincubation with the selective CB{sub 1} receptor antagonist AM251, but not with the selective CB{sub 2} receptor antagonist AM630. Furthermore, annexin-V-positive cells were found among the treated forebrain cells. Synthetic cannabinoid treatment induced the activation of caspase-3, and preincubation with a caspase-3 inhibitor significantly suppressed the cytotoxicity. These synthetic cannabinoids induced apoptosis through a caspase-3-dependent mechanism in the forebrain cultures. Our results indicate that the cytotoxicity of synthetic cannabinoids towards primary neuronal cells is mediated by the CB{sub 1} receptor, but not by the CB{sub 2} receptor, and further suggest that caspase cascades may play an important role in the apoptosis induced by these synthetic cannabinoids. In conclusion, excessive synthetic cannabinoid abuse may present a serious acute health concern due to neuronal damage or deficits in the brain. - Highlights: • Synthetic cannabinoids (classical cannabinoids, non-classical cannabinoids, and aminoalkylindole derivatives) induce cytotoxicity in mouse forebrain cultures. • Synthetic cannabinoid-induced cytotoxicity towards forebrain cultures is mediated by the CB{sub 1} receptor, but not by the CB{sub 2} receptor, and involves caspase-dependent apoptosis. • A high concentration of synthetic cannabinoids may be toxic to neuronal cells that express CB{sub 1} receptors.

  18. Cytotoxicity of synthetic cannabinoids on primary neuronal cells of the forebrain: the involvement of cannabinoid CB1 receptors and apoptotic cell death

    International Nuclear Information System (INIS)

    The abuse of herbal products containing synthetic cannabinoids has become an issue of public concern. The purpose of this paper was to evaluate the acute cytotoxicity of synthetic cannabinoids on mouse brain neuronal cells. Cytotoxicity induced by synthetic cannabinoid (CP-55,940, CP-47,497, CP-47,497-C8, HU-210, JWH-018, JWH-210, AM-2201, and MAM-2201) was examined using forebrain neuronal cultures. These synthetic cannabinoids induced cytotoxicity in the forebrain cultures in a concentration-dependent manner. The cytotoxicity was suppressed by preincubation with the selective CB1 receptor antagonist AM251, but not with the selective CB2 receptor antagonist AM630. Furthermore, annexin-V-positive cells were found among the treated forebrain cells. Synthetic cannabinoid treatment induced the activation of caspase-3, and preincubation with a caspase-3 inhibitor significantly suppressed the cytotoxicity. These synthetic cannabinoids induced apoptosis through a caspase-3-dependent mechanism in the forebrain cultures. Our results indicate that the cytotoxicity of synthetic cannabinoids towards primary neuronal cells is mediated by the CB1 receptor, but not by the CB2 receptor, and further suggest that caspase cascades may play an important role in the apoptosis induced by these synthetic cannabinoids. In conclusion, excessive synthetic cannabinoid abuse may present a serious acute health concern due to neuronal damage or deficits in the brain. - Highlights: • Synthetic cannabinoids (classical cannabinoids, non-classical cannabinoids, and aminoalkylindole derivatives) induce cytotoxicity in mouse forebrain cultures. • Synthetic cannabinoid-induced cytotoxicity towards forebrain cultures is mediated by the CB1 receptor, but not by the CB2 receptor, and involves caspase-dependent apoptosis. • A high concentration of synthetic cannabinoids may be toxic to neuronal cells that express CB1 receptors

  19. 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

  20. 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.

  1. Cannabinoid inhibition of the capsaicin-induced calcium response in rat dorsal root ganglion neurones

    OpenAIRE

    Millns, Paul J; Chapman, Victoria; Kendall, David A.

    2001-01-01

    Cannabinoids have marked inhibitory effects on somatosensory processing, which may arise from actions at both peripheral and central cannabinoid receptors. Here, the effect of a synthetic cannabinoid agonist HU210 on capsaicin-evoked responses in adult rat dorsal root ganglion (DRG) neurones was studied. The vanilloid capsaicin produced a concentration-related increase in intracellular calcium in DRG neurones, which was significantly inhibited by HU210 (1 μM). The cannabinoid CB1 receptor ant...

  2. 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

  3. 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.

  4. 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 ....... In total, over 100 compounds are described by means of chemical structure and available pharmacological data. With this perspective review, it is our intention to ignite and stimulate inspiration for future design and synthesis of novel subtype selective KA receptor agonists....

  5. Attenuation of morphine antinociceptive tolerance by cannabinoid CB1 and CB2 receptor antagonists.

    Science.gov (United States)

    Altun, Ahmet; Yildirim, Kemal; Ozdemir, Ercan; Bagcivan, Ihsan; Gursoy, Sinan; Durmus, Nedim

    2015-09-01

    Cannabinoid CB1 and CB2 receptor antagonists may be useful for their potential to increase or prolong opioid analgesia while attenuating the development of opioid tolerance. The aim of this study was to investigate the effects of AM251 (a selective CB1 antagonist) and JTE907 (a selective CB2 antagonist) on morphine analgesia and tolerance in rats. Adult male Wistar albino rats weighing 205-225 g were used in these experiments. To constitute morphine tolerance, we used a 3 day cumulative dosing regimen. After the last dose of morphine was injected on day 4, morphine tolerance was evaluated by analgesia tests. The analgesic effects of morphine (5 mg/kg), ACEA (a CB1 receptor agonist, 5 mg/kg), JWH-015 (a CB2 receptor agonist, 5 mg/kg), AM251 (1 mg/kg) and JTE907 (5 mg/kg) were considered at 30-min intervals (0, 30, 60, 90, and 120 min) by tail-flick and hot-plate analgesia tests. Our findings indicate that ACEA and JWH907 significantly increased morphine analgesia and morphine antinociceptive tolerance in the analgesia tests. In contrast, the data suggested that AM251 and JTE907 significantly attenuated the expression of morphine tolerance. In conclusion, we observed that co-injection of AM251 and JTE907 with morphine attenuated expression of tolerance to morphine analgesic effects and decreased the morphine analgesia. PMID:25894754

  6. 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...... system, is involved in cortical activation and is important in the development of drug addiction-associated behaviours. Therefore, eCBs might exert behavioural effects by actions on the LDT; however, it is unknown whether eCBs have actions on neurons in this nucleus. Accordingly, whole-cell voltage- and...... changes 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...

  7. Cannabinoid receptor activation reverses kainate-induced synchronized population burst firing in rat hippocampus

    OpenAIRE

    Rob Mason; Cheer, Joseph F

    2009-01-01

    Cannabinoids have been shown to possess anticonvulsant properties in whole animal models of epilepsy. The present investigation sought to examine the effects of cannabinoid receptor activation on kainic acid (KA)-induced epileptiform neuronal excitability. Under urethane anesthesia, acute KA treatment (10 mg/kg, i.p.) entrained the spiking mode of simultaneously recorded neurons from random firing to synchronous bursting (% change in burst rate). Injection of the high-affinity cannabinoid a...

  8. Cannabinoid Receptor Activation Reverses Kainate-Induced Synchronized Population Burst Firing in Rat Hippocampus

    OpenAIRE

    Mason, Rob; Cheer, Joseph F

    2009-01-01

    Cannabinoids have been shown to possess anticonvulsant properties in whole animal models of epilepsy. The present investigation sought to examine the effects of cannabinoid receptor activation on kainic acid (KA)-induced epileptiform neuronal excitability. Under urethane anesthesia, acute KA treatment (10 mg kg−1, i.p.) entrained the spiking mode of simultaneously recorded neurons from random firing to synchronous bursting (% change in burst rate). Injection of the high-affinity cannabinoid a...

  9. 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

  10. 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 ...

  11. 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

  12. Cannabinoid Type 1 Receptors Transiently Silence Glutamatergic Nerve Terminals of Cultured Cerebellar Granule Cells

    OpenAIRE

    Ramírez-Franco, Jorge; Bartolomé-Martín, David; Alonso, Beatris; Torres, Magdalena; Sánchez-Prieto, José

    2014-01-01

    Cannabinoid receptors are the most abundant G protein-coupled receptors in the brain and they mediate retrograde short-term inhibition of neurotransmitter release, as well as long-term depression of synaptic transmission at many excitatory synapses. The induction of presynaptically silent synapses is a means of modulating synaptic strength, which is important for synaptic plasticity. Persistent activation of cannabinoid type 1 receptors (CB1Rs) mutes GABAergic terminals, although it is unclea...

  13. Functional residues essential for the activation of the CB1 cannabinoid receptor.

    Science.gov (United States)

    Shim, Joong-Youn; Padgett, Lea

    2013-01-01

    Recently developed X-ray crystal structures of active state G-protein-coupled receptors have opened the way for detailed examination of the movement of the transmembrane (TM) helices and the specific residues involved in the receptor activation upon ligand binding. Previous modeling studies have indicated that the brain cannabinoid (CB1) receptor binds with a ligand at least in part through a hydrophobic tail on the ligand. This interaction is believed to be similar to the rotameric toggle switch proposed for the β2 adrenergic receptor (β2AR). In the present study, an active state model for the CB1 receptor, guided by the X-ray structure of the active state for β2AR, was constructed with HU210 bound as a ligand. Molecular dynamics (MD) simulations were employed to provide a smooth progression between inactive and active states of the receptor. This model was compared with our previously published CB1 receptor model to identify the functional residues that play key roles in triggering receptor conformational changes upon agonist binding. Movements in TM helices and functional residues are discussed. W279(5.43), contributing to an inward movement of the fifth TM helix (TM5) to the helical core, could serve as another rotameric switch for receptor activation. V282(5.46), interacting with the ligand's hydrophobic C3 alkyl chain, appears to play a key role in TM5 inward movement centered at L286(5.50) and subsequent coupling to V204(3.40). V204(3.40), closely interacting with the TM5 and TM6 hydrophobic patch residues in the middle of the receptor, particularly I290(5.54) and L352(6.44), appears to facilitate helical rearrangements, leading to the breakage of the ionic lock and the rotameric change of Y397(7.53), which are key features of the active state. PMID:23332708

  14. 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

  15. Cannabinoid effects on CB1 receptor density in the adolescent brain: an autoradiographic study using the synthetic cannabinoid HU210.

    Science.gov (United States)

    Dalton, Victoria S; Zavitsanou, Katerina

    2010-11-01

    The short- and long-term behavioral effects of cannabinoids differ in adolescent and adult rodents. Few studies though have examined the underlying neurochemical changes that occur in the brain following adolescent cannabinoid exposure. In this study, we examined the effect of treatment with the synthetic cannabinoid, HU210, on CB1 receptor density in the brain and on body weight in adolescent male rats. Rats were treated daily with 25, 50, or 100 μg/kg HU210 for 4 or 14 days, or received a single dose of 100 μg/kg HU210 and sacrificed 24 h later. Receptor density was investigated using in vitro autoradiography with the CB1 receptor ligand [(3)H] CP55,940. In contrast to adult animals treated under the same paradigm in a previous study, adolescents continued on average, to gain weight over the course of the study. Weight gain was slowest in the 100 μg/kg group and improved dose dependently with controls gaining the most weight. Following the acute dose of HU210, a trend for a reduction in [(3)H] CP55,940 binding and a significant effect of treatment was observed. Statistically significant, dose-dependent, region-specific decreases in binding were observed in all brain regions examined following 4 and 14 days treatment. The pattern of CB1 receptor downregulation was similar to that observed in adults treated with cannabinoids in previous studies; however, its magnitude was smaller in adolescents. This reduced compensatory response may contribute to some acute behavioral effects, the pharmacological cross-tolerance and the long-lasting, adverse psychological consequences of cannabinoid exposure during adolescence. PMID:20842718

  16. Cannabinoid receptor 1 suppresses transient receptor potential vanilloid 1-induced inflammatory responses to corneal injury

    OpenAIRE

    Yang, Y.; Yang, H.; Wang, Z; Varadaraj, K; Kumari, S.S.; Mergler, S; Okada, Y.; Saika, S.; Kingsley, P J; Marnett, L J; Reinach, P.S.

    2012-01-01

    Cannabinoid receptor type 1 (CB1)-induced suppression of transient receptor potential vanilloid type 1 (TRPV1) activation provides a therapeutic option to reduce inflammation and pain in different animal disease models through mechanisms involving dampening of TRPV1 activation and signaling events. As we found in both mouse corneal epithelium and human corneal epithelial cells (HCEC) that there is CB1 and TRPV1 expression colocalization based on overlap of coimmunostaining, we determined in m...

  17. 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

  18. 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

  19. Inhibition of platelet aggregation by vanilloid-like agents is not mediated by transient receptor potential vanilloid-1 channels or cannabinoid receptors.

    Science.gov (United States)

    Almaghrabi, Safa; Geraghty, Dominic; Ahuja, Kiran; Adams, Murray

    2016-06-01

    Vanilloid-like agents, including capsaicin, N-arachidonoyl-dopamine and N-oleoyldopamine inhibit platelet aggregation, however little is known about the precise mechanism(s) of action. The authors have previously shown that blocking of the capsaicin receptor, transient receptor potential vanilloid-1 (TRPV1), does not interfere with capsaicin action during adenosine diphosphate (ADP)-induced aggregation. This research is extended to investigate the effect of these vanilloid-like-agents on platelet count, and to test whether the effect of these agents is mediated through TRPV1 and/or cannabinoid (CB1 and CB2) receptors in the presence of other agonists, including collagen and arachidonic acid. Incubation of platelets with each of the individual vanilloids, or with receptor antagonists of TRPV1 (SB452533), CB1 (AM251) and CB2 (AM630), for up to 2 h did not significantly affect the platelet count. Similarly, the effect of individual vanilloids on the inhibition of platelet aggregation was not significantly different in the presence of receptor agonists compared to control, irrespective of the agonist used, suggesting that the inhibitory effect of vanilloids on platelet aggregation is independent of TRPV1, CB1 and CB2 receptors. Further research on the antiplatelet activity of vanilloids should focus on mechanisms other than those associated with vanilloid receptors. PMID:26991025

  20. Cannabinoid receptor activation in the rostral ventrolateral medulla oblongata evokes cardiorespiratory effects in anaesthetised rats

    OpenAIRE

    Padley, James R; Li, Qun; Pilowsky, Paul M.; Goodchild, Ann K

    2003-01-01

    The nature of the cardiorespiratory effects mediated by cannabinoids in the hindbrain is poorly understood. In the present study we investigated whether cannabinoid receptor activation in the rostral ventrolateral medulla oblongata (RVLM) affects cardiovascular and/or respiratory function.Initially, we looked for evidence of CB1 receptor gene expression in rostral and caudal sections of the rat ventrolateral medulla (VLM) using reverse transcription–polymerase chain reaction. Second, the pote...

  1. 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

  2. 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...

  3. 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

    Antipsychotic drugs may cause extrapyramidal symptoms (EPS), such as dyskinesia and dystonia. These effects are believed to involve dysfunctional striatal dopamine transmission. Patients with schizophrenia show increased prevalence of cannabis abuse and this has been linked to severity of EPS....... 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...

  4. 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...

  5. Lack of positive allosteric modulation of mutated alpha(1)S267I glycine receptors by cannabinoids.

    Science.gov (United States)

    Foadi, Nilufar; Leuwer, Martin; Demir, Reyhan; Dengler, Reinhard; Buchholz, Vanessa; de la Roche, Jeanne; Karst, Matthias; Haeseler, Gertrud; Ahrens, Jörg

    2010-05-01

    Loss of inhibitory synaptic transmission within the dorsal horn of the spinal cord plays a key role in the development of chronic pain following inflammation or nerve injury. Inhibitory postsynaptic transmission in the adult spinal cord involves mainly glycine. Ajulemic acid and HU210 are non-psychotropic, synthetic cannabinoids. Cannabidiol is a non-psychotropic plant constituent of cannabis sativa. There are hints that non-cannabinoid receptor mechanisms of these cannabinoids might be mediated via glycine receptors. In this study, we investigated the impact of the amino acid residue serine at position 267 on the glycine-modulatory effects of ajulemic acid, cannabidiol and HU210. Mutated alpha(1)S267I glycine receptors transiently expressed in HEK293 cells were studied by utilising the whole-cell clamp technique. The mutation of the alpha(1) subunit TM2 serine residue to isoleucine abolished the co-activation and the direct activation of the glycine receptor by the investigated cannabinoids. The nature of the TM2 (267) residue of the glycine alpha(1) subunit is crucial for the glycine-modulatory effect of ajulemic acid, cannabidiol and HU210. An investigation of the impact of such mutations on the in vivo interaction of cannabinoids with glycine receptors should permit a better understanding of the molecular determinants of action of cannabinoids. PMID:20339834

  6. 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

  7. 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 with....... 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 in...... 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 and...

  8. 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.

  9. A runner’s high depends on cannabinoid receptors in mice

    Science.gov (United States)

    Fuss, Johannes; Steinle, Jörg; Bindila, Laura; Auer, Matthias K.; Kirchherr, Hartmut; Lutz, Beat; Gass, Peter

    2015-01-01

    Exercise is rewarding, and long-distance runners have described a runner’s high as a sudden pleasant feeling of euphoria, anxiolysis, sedation, and analgesia. A popular belief has been that endogenous endorphins mediate these beneficial effects. However, running exercise increases blood levels of both β-endorphin (an opioid) and anandamide (an endocannabinoid). Using a combination of pharmacologic, molecular genetic, and behavioral studies in mice, we demonstrate that cannabinoid receptors mediate acute anxiolysis and analgesia after running. We show that anxiolysis depends on intact cannabinoid receptor 1 (CB1) receptors on forebrain GABAergic neurons and pain reduction on activation of peripheral CB1 and CB2 receptors. We thus demonstrate that the endocannabinoid system is crucial for two main aspects of a runner's high. Sedation, in contrast, was not influenced by cannabinoid or opioid receptor blockage, and euphoria cannot be studied in mouse models. PMID:26438875

  10. Quantifying Agonist Activity at G Protein-coupled Receptors

    OpenAIRE

    Ehlert, Frederick J.; Suga, Hinako; Griffin, Michael T.

    2011-01-01

    When an agonist activates a population of G protein-coupled receptors (GPCRs), it elicits a signaling pathway that culminates in the response of the cell or tissue. This process can be analyzed at the level of a single receptor, a population of receptors, or a downstream response. Here we describe how to analyze the downstream response to obtain an estimate of the agonist affinity constant for the active state of single receptors.

  11. Cannabinoid receptor-interacting protein Crip1a modulates CB1 receptor signaling in mouse hippocampus.

    Science.gov (United States)

    Guggenhuber, Stephan; Alpar, Alan; Chen, Rongqing; Schmitz, Nina; Wickert, Melanie; Mattheus, Tobias; Harasta, Anne E; Purrio, Martin; Kaiser, Nadine; Elphick, Maurice R; Monory, Krisztina; Kilb, Werner; Luhmann, Heiko J; Harkany, Tibor; Lutz, Beat; Klugmann, Matthias

    2016-05-01

    The cannabinoid type 1 receptor (Cnr1, CB1R) mediates a plethora of physiological functions in the central nervous system as a presynaptic modulator of neurotransmitter release. The recently identified cannabinoid receptor-interacting protein 1a (Cnrip1a, CRIP1a) binds to the C-terminal domain of CB1R, a region known to be important for receptor desensitization and internalization. Evidence that CRIP1a and CB1R interact in vivo has been reported, but the neuroanatomical distribution of CRIP1a is unknown. Moreover, while alterations of hippocampal CRIP1a levels following limbic seizures indicate a role in controlling excessive neuronal activity, the physiological function of CRIP1a in vivo has not been investigated. In this study, we analyzed the spatial distribution of CRIP1a in the hippocampus and examined CRIP1a as a potential modulator of CB1R signaling. We found that Cnrip1a mRNA is co-expressed with Cnr1 mRNA in pyramidal neurons and interneurons of the hippocampal formation. CRIP1a protein profiles were largely segregated from CB1R profiles in mossy cell terminals but not in hippocampal CA1 region. CB1R activation induced relocalization to close proximity with CRIP1a. Adeno-associated virus-mediated overexpression of CRIP1a specifically in the hippocampus revealed that CRIP1a modulates CB1R activity by enhancing cannabinoid-induced G protein activation. CRIP1a overexpression extended the depression of excitatory currents by cannabinoids in pyramidal neurons of the hippocampus and diminished the severity of chemically induced acute epileptiform seizures. Collectively, our data indicate that CRIP1a enhances hippocampal CB1R signaling in vivo. PMID:25772509

  12. Ghrelin and cannabinoids require the ghrelin receptor to affect cellular energy metabolism

    OpenAIRE

    Lim, Chung Thong; Kola, Blerina; Feltrin, Daniel; Perez-Tilve, Diego; Tschöp, Matthias H.; Grossman, Ashley B; Korbonits, Márta

    2013-01-01

    Introduction Ghrelin is a potent orexigenic brain-gut peptide with lipogenic and diabetogenic effects, possibly mediated by growth hormone secretagogue receptor (GHS-R1a). Cannabinoids also have orexigenic and lipogenic effects. AMPK is a regulator of energy homeostasis and we have previously shown that ghrelin and cannabinoids stimulate hypothalamic AMPK activity while inhibiting it in the liver and adipose tissue, suggesting that AMPK mediates both the central appetite-inducing and peripher...

  13. 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...

  14. CB2 receptor agonists protect human dopaminergic neurons against damage from HIV-1 gp120.

    Directory of Open Access Journals (Sweden)

    Shuxian Hu

    Full Text Available Despite the therapeutic impact of anti-retroviral therapy, HIV-1-associated neurocognitive disorder (HAND remains a serious threat to AIDS patients, and there currently remains no specific therapy for the neurological manifestations of HIV-1. Recent work suggests that the nigrostriatal dopaminergic area is a critical brain region for the neuronal dysfunction and death seen in HAND and that human dopaminergic neurons have a particular sensitivity to gp120-induced damage, manifested as reduced function (decreased dopamine uptake, morphological changes, and reduced viability. Synthetic cannabinoids inhibit HIV-1 expression in human microglia, suppress production of inflammatory mediators in human astrocytes, and there is substantial literature demonstrating the neuroprotective properties of cannabinoids in other neuropathogenic processes. Based on these data, experiments were designed to test the hypothesis that synthetic cannabinoids will protect dopaminergic neurons against the toxic effects of the HIV-1 protein gp120. Using a human mesencephalic neuronal/glial culture model, which contains dopaminergic neurons, microglia, and astrocytes, we were able to show that the CB1/CB2 agonist WIN55,212-2 blunts gp120-induced neuronal damage as measured by dopamine transporter function, apoptosis and lipid peroxidation; these actions were mediated principally by the CB2 receptor. Adding supplementary human microglia to our cultures enhances gp120-induced damage; WIN55,212-2 is able to alleviate this enhanced damage. Additionally, WIN55,212-2 inhibits gp120-induced superoxide production by purified human microglial cells, inhibits migration of human microglia towards supernatants generated from gp120-stimulated human mesencephalic neuronal/glial cultures and reduces chemokine and cytokine production from the human mesencephalic neuronal/glial cultures. These data suggest that synthetic cannabinoids are capable of protecting human dopaminergic neurons from

  15. [18F]MK-9470, a positron emission tomography (PET) tracer for in vivo human PET brain imaging of the cannabinoid-1 receptor

    OpenAIRE

    Burns, H. Donald; Van Laere, Koen; Sanabria-Bohórquez, Sandra; Hamill, Terence G.; Bormans, Guy; Eng, Wai-si; Gibson, Ray; Ryan, Christine; Connolly, Brett; Patel, Shil; Krause, Stephen; Vanko, Amy; Van Hecken, Anne; DUPONT, Patrick; De Lepeleire, Inge

    2007-01-01

    [(18)F]MK-9470 is a selective, high-affinity, inverse agonist (human IC(50), 0.7 nM) for the cannabinoid CB1 receptor (CB1R) that has been developed for use in human brain imaging. Autoradiographic studies in rhesus monkey brain showed that [(18)F]MK-9470 binding is aligned with the reported distribution of CB1 receptors with high specific binding in the cerebral cortex, cerebellum, caudate/putamen, globus pallidus, substantia nigra, and hippocampus. Positron emission tomography (PET) imaging...

  16. 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.

  17. 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

  18. 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

  19. A study of functional selectivity at the cannabinoid type 1 receptor

    OpenAIRE

    Priestley, Richard

    2015-01-01

    The cannabinoid CB1 receptor is a G protein-coupled receptor (GPCR) which is important in the regulation of neuronal function, predominately via coupling to heterotrimeric Gi/o proteins. The receptor has also been shown to interact with a variety of other intracellular signalling mediators, including other G proteins, several members of the mitogen activated kinase (MAP) superfamily and β-arrestins. The CB1 receptor is recognised by an array of structurally distinct endogenous and exogenous l...

  20. 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

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

    OpenAIRE

    Lax Zapata, Pedro; Esquiva Sobrino, Gema; Altavilla, Cesare; Cuenca Navarro, Nicolás

    2014-01-01

    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...

  2. Octopaminergic agonists for the cockroach neuronal octopamine receptor

    Directory of Open Access Journals (Sweden)

    Akinori Hirashima

    2003-04-01

    Full Text Available The compounds 1-(2,6-diethylphenylimidazolidine-2-thione and 2-(2,6-diethylphenylimidazolidine showed the almost same activity as octopamine in stimulating adenylate cyclase of cockroach thoracic nervous system among 70 octopamine agonists, suggesting that only these compounds are full octopamine agonists and other compounds are partial octopamine agonists. The quantitative structure-activity relationship of a set of 22 octopamine agonists against receptor 2 in cockroach nervous tissue, was analyzed using receptor surface modeling. Three-dimensional energetics descriptors were calculated from receptor surface model/ligand interaction and these three-dimensional descriptors were used in quantitative structure-activity relationship analysis. A receptor surface model was generated using some subset of the most active structures and the results provided useful information in the characterization and differentiation of octopaminergic receptor.

  3. Activation of cannabinoid receptor 2 reduces inflammation in acute experimental pancreatitis via intra-acinar activation of p38 and MK2-dependent mechanisms.

    Science.gov (United States)

    Michler, Thomas; Storr, Martin; Kramer, Johannes; Ochs, Stefanie; Malo, Antje; Reu, Simone; Göke, Burkhard; Schäfer, Claus

    2013-01-15

    The endocannabinoid system has been shown to mediate beneficial effects on gastrointestinal inflammation via cannabinoid receptors 1 (CB(1)) and 2 (CB(2)). These receptors have also been reported to activate the MAP kinases p38 and c-Jun NH(2)-terminal kinase (JNK), which are involved in early acinar events leading to acute pancreatitis and induction of proinflammatory cytokines. Our aim was to examine the role of cannabinoid receptor activation in an experimental model of acute pancreatitis and the potential involvement of MAP kinases. Cerulein pancreatitis was induced in wild-type, CB(1)-/-, and MK2-/- mice pretreated with selective cannabinoid receptor agonists or antagonists. Severity of pancreatitis was determined by serum amylase and IL-6 levels, intracellular activation of pancreatic trypsinogen, lung myeloperoxidase activity, pancreatic edema, and histological examinations. Pancreatic lysates were investigated by Western blotting using phospho-specific antibodies against p38 and JNK. Quantitative PCR data, Western blotting experiments, and immunohistochemistry clearly show that CB(1) and CB(2) are expressed in mouse pancreatic acini. During acute pancreatitis, an upregulation especially of CB(2) on apoptotic cells occurred. The unselective CB(1)/CB(2) agonist HU210 ameliorated pancreatitis in wild-type and CB(1)-/- mice, indicating that this effect is mediated by CB(2). Furthermore, blockade of CB(2), not CB(1), with selective antagonists engraved pathology. Stimulation with a selective CB(2) agonist attenuated acute pancreatitis and an increased activation of p38 was observed in the acini. With use of MK2-/- mice, it could be demonstrated that this attenuation is dependent on MK2. Hence, using the MK2-/- mouse model we reveal a novel CB(2)-activated and MAP kinase-dependent pathway that modulates cytokine expression and reduces pancreatic injury and affiliated complications. PMID:23139224

  4. Species differences in cannabinoid receptor 2 and receptor responses to cocaine self-administration in mice and rats.

    Science.gov (United States)

    Zhang, Hai-Ying; Bi, Guo-Hua; Li, Xia; Li, Jie; Qu, Hong; Zhang, Shi-Jian; Li, Chuan-Yun; Onaivi, Emmanuel S; Gardner, Eliot L; Xi, Zheng-Xiong; Liu, Qing-Rong

    2015-03-01

    The discovery of functional cannabinoid receptors 2 (CB2Rs) in brain suggests a potential new therapeutic target for neurological and psychiatric disorders. However, recent findings in experimental animals appear controversial. Here we report that there are significant species differences in CB2R mRNA splicing and expression, protein sequences, and receptor responses to CB2R ligands in mice and rats. Systemic administration of JWH133, a highly selective CB2R agonist, significantly and dose-dependently inhibited intravenous cocaine self-administration under a fixed ratio (FR) schedule of reinforcement in mice, but not in rats. However, under a progressive ratio (PR) schedule of reinforcement, JWH133 significantly increased breakpoint for cocaine self-administration in rats, but decreased it in mice. To explore the possible reasons for these conflicting findings, we examined CB2R gene expression and receptor structure in the brain. We found novel rat-specific CB2C and CB2D mRNA isoforms in addition to CB2A and CB2B mRNA isoforms. In situ hybridization RNAscope assays found higher levels of CB2R mRNA in different brain regions and cell types in mice than in rats. By comparing CB2R-encoding regions, we observed a premature stop codon in the mouse CB2R gene that truncated 13 amino-acid residues including a functional autophosphorylation site in the intracellular C-terminus. These findings suggest that species differences in the splicing and expression of CB2R genes and receptor structures may in part explain the different effects of CB2R-selective ligands on cocaine self-administration in mice and rats. PMID:25374096

  5. 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.; Azcoitia, I.; Hansen, Harald S.; Pons, S.; García-Segura, L.M.; Romero, 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...

  6. [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

  7. 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...

  8. IMIDAZOLINE RECEPTOR AGONISTS: DO WE KNOW EVERYTHING ABOUT THEIR CAPABILITIES?

    Directory of Open Access Journals (Sweden)

    D. V. Nebieridze

    2015-12-01

    Full Text Available The role of selective I1 imidazoline receptor agonists and moxonidine in particular , in modern antihypertensive therapy is discussed. Moxonidine advantages, namely positive effects on insulin resistance, endothelial dysfunction, lipid profile, and plasma fibrinolytic activity are considered.

  9. On the Role of Cannabinoid CB1- and μ-Opioid Receptors in Motor Impulsivity

    OpenAIRE

    Wiskerke, Joost; van Mourik, Yvar; Schetters, Dustin; Schoffelmeer, Anton N. M.; Pattij, Tommy

    2012-01-01

    Previous studies using a rat 5-choice serial reaction time task have established a critical role for dopamine D2 receptors in regulating increments in motor impulsivity induced by acute administration of the psychostimulant drugs amphetamine and nicotine. Here we investigated whether cannabinoid CB1 and/or μ-opioid receptors are involved in nicotine-induced impulsivity, given recent findings indicating that both receptor systems mediate amphetamine-induced motor impulsivity. Results showed th...

  10. 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

  11. Cannabinoid activation of peroxisome proliferator-activated receptors: potential for modulation of inflammatory disease.

    Science.gov (United States)

    O'Sullivan, S E; Kendall, D A

    2010-08-01

    Cannabinoids act via cell surface G protein-coupled receptors (CB(1) and CB(2)) and the ion channel receptor TRPV1. Evidence has now emerged suggesting that an additional target is the peroxisome proliferator-activated receptor (PPAR) family of nuclear receptors. There are three PPAR subtypes alpha, delta (also known as beta) and gamma, which regulate cell differentiation, metabolism and immune function. The major endocannabinoids, anandamide and 2-arachidonoylglycerol, and ajulemic acid, a structural analogue of the phytocannabinoid Delta(9)-tetrahydrocannabinol (THC), have anti-inflammatory properties mediated by PPARgamma. Other cannabinoids which activate PPARgamma include N-arachidonoyl-dopamine, THC, cannabidiol, HU210, WIN55212-2 and CP55940. The endogenous acylethanolamines, oleoylethanolamide and palmitoylethanolamide regulate feeding and body weight, stimulate fat utilization and have neuroprotective effects mediated through PPARalpha. Other endocannabinoids that activate PPARalpha include anandamide, virodhamine and noladin ether. There is, as yet, little direct evidence for interactions of cannabinoids with PPARdelta. There is a convergence of effects of cannabinoids, acting via cell surface and nuclear receptors, on immune cell function which provides promise for the targeted therapy of a variety of immune, particularly neuroinflammatory, diseases. PMID:19833407

  12. (+)-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

  13. 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

  14. 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

  15. 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...

  16. 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

  17. 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

  18. 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

  19. 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. PMID:24495949

  20. 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.

  1. 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…

  2. 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...

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

    Directory of Open Access Journals (Sweden)

    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

  4. LiCABEDS II. Modeling of ligand selectivity for G-protein-coupled cannabinoid receptors.

    Science.gov (United States)

    Ma, Chao; Wang, Lirong; Yang, Peng; Myint, Kyaw Z; Xie, Xiang-Qun

    2013-01-28

    The cannabinoid receptor subtype 2 (CB2) is a promising therapeutic target for blood cancer, pain relief, osteoporosis, and immune system disease. The recent withdrawal of Rimonabant, which targets another closely related cannabinoid receptor (CB1), accentuates the importance of selectivity for the development of CB2 ligands in order to minimize their effects on the CB1 receptor. In our previous study, LiCABEDS (Ligand Classifier of Adaptively Boosting Ensemble Decision Stumps) was reported as a generic ligand classification algorithm for the prediction of categorical molecular properties. Here, we report extension of the application of LiCABEDS to the modeling of cannabinoid ligand selectivity with molecular fingerprints as descriptors. The performance of LiCABEDS was systematically compared with another popular classification algorithm, support vector machine (SVM), according to prediction precision and recall rate. In addition, the examination of LiCABEDS models revealed the difference in structure diversity of CB1 and CB2 selective ligands. The structure determination from data mining could be useful for the design of novel cannabinoid lead compounds. More importantly, the potential of LiCABEDS was demonstrated through successful identification of newly synthesized CB2 selective compounds. PMID:23278450

  5. 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...

  6. Cannabinoids in health and disease

    OpenAIRE

    Kogan, Natalya M.; Mechoulam, Raphael

    2007-01-01

    Cannabis sativa L. preparations have been used in medicine for millenia. However, concern over the dangers of abuse led to the banning of the medicinal use of marijuana in most countries in the 1930s. Only recently, marijuana and individual natural and synthetic cannabinoid receptor agonists and antagonists, as well as chemically related compounds, whose mechanism of action is still obscure, have come back to being considered of therapeutic value. However, their use is highly restricted. Desp...

  7. Type 1 cannabinoid receptor modulates water deprivation-induced homeostatic responses.

    Science.gov (United States)

    Ruginsk, Silvia G; Vechiato, Fernanda M V; Uchoa, Ernane T; Elias, Lucila L K; Antunes-Rodrigues, Jose

    2015-12-01

    The present study investigated the type 1 cannabinoid receptor (CB1R) as a potential candidate to mediate the homeostatic responses triggered by 24 h of water deprivation, which constitutes primarily a hydroelectrolytic challenge and also significantly impacts energy homeostasis. The present results demonstrated for the first time that CB1R mRNA expression is increased in the hypothalamus of water-deprived (WD) rats. Furthermore, the administration of ACEA, a CB1R selective agonist, potentiated WD-induced dipsogenic effect, whereas AM251, a CB1R antagonist, attenuated not only water but also salt intake in response to WD. In parallel with the modulation of thirst and salt appetite, we confirmed that CB1Rs are essential for the development of appropriated neuroendocrine responses. Although the administration of ACEA or AM251 did not produce any effects on WD-induced arginine vasopressin (AVP) secretion, oxytocin (OXT) plasma concentrations were significantly decreased in WD rats treated with ACEA. At the genomic level, ACEA significantly decreased AVP and OXT mRNA expression in the hypothalamus of WD rats, whereas AM251 potentiated both basal and WD-induced stimulatory effects on the transcription of AVP and OXT genes. In addition, we showed that water deprivation alone upregulated proopiomelanocortin, Agouti-related peptide, melanin-concentrating hormone, and orexin A mRNA levels in the hypothalamus, and that CB1Rs regulate main central peptidergic pathways controlling food intake, being that most of these effects were also significantly influenced by the hydration status. In conclusion, the present study demonstrated that CB1Rs participate in the homeostatic responses regulating fluid balance and energy homeostasis during water deprivation. PMID:26468265

  8. Antagonism of Dopamine Receptor 2 Long Affects Cannabinoid Receptor 1 Signaling in a Cell Culture Model of Striatal Medium Spiny Projection Neurons.

    Science.gov (United States)

    Bagher, Amina M; Laprairie, Robert B; Kelly, Melanie E M; Denovan-Wright, Eileen M

    2016-06-01

    Activation of dopamine receptor 2 long (D2L) switches the signaling of type 1 cannabinoid receptor (CB1) from Gαi to Gαs, a process thought to be mediated through CB1-D2L heteromerization. Given the clinical importance of D2 antagonists, the goal of this study was to determine if D2 antagonists could modulate CB1 signaling. Interactions between CB1 and D2L, Gαi, Gαs, and β-arrestin1 were studied using bioluminescence resonance energy transfer 2 (BRET(2)) in STHdh(Q7/Q7) cells. CB1-dependent extracellular regulated kinase (ERK)1/2, CREB phosphorylation, and CB1 internalization following cotreatment of CB1 agonist and D2 antagonist were quantified. Preassembled CB1-Gαi complexes were detected by BRET(2) Arachidonyl-2'-chloroethylamide (ACEA), a selective CB1 agonist, caused a rapid and transient increase in BRET efficiency (BRETEff) between Gαi-Rluc and CB1-green fluorescent protein 2 (GFP(2)), and a Gαi-dependent increase in ERK phosphorylation. Physical interactions between CB1 and D2L were observed using BRET(2) Cotreatment of STHdh(Q7/Q7) cells with ACEA and haloperidol, a D2 antagonist, inhibited BRETEff signals between Gαi-Rluc and CB1-GFP(2) and reduced the EMax and pEC50 of ACEA-mediated Gαi-dependent ERK phosphorylation. ACEA and haloperidol cotreatments produced a delayed and sustained increase in BRETEff between Gαs-Rluc and CB1-GFP(2) and increased the EMax and pEC50 of ACEA-induced Gαs-dependent cAMP response element-binding protein phosphorylation. In cells expressing CB1 and D2L treated with ACEA, binding of haloperidol to D2 receptors switched CB1 coupling from Gαi to Gαs In addition, haloperidol treatment reduced ACEA-induced β-arrestin1 recruitment to CB1 and CB1 internalization. D2 antagonists allosterically modulate cannabinoid-induced CB1 coupling, signaling, and β-arrestin1 recruitment through binding to CB1-D2L heteromers. These findings indicate that D2 antagonism, like D2 agonists, change agonist-mediated CB1 coupling and

  9. In silico discovery of novel Retinoic Acid Receptor agonist structures

    OpenAIRE

    Samuels Herbert H; Schapira Matthieu; Raaka Bruce M; Abagyan Ruben

    2001-01-01

    Abstract Background Several Retinoic Acid Receptors (RAR) agonists have therapeutic activity against a variety of cancer types; however, unacceptable toxicity profiles have hindered the development of drugs. RAR agonists presenting novel structural and chemical features could therefore open new avenues for the discovery of leads against breast, lung and prostate cancer or leukemia. Results We have analysed the induced fit of the active site residues upon binding of a known ligand. The derived...

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

    Science.gov (United States)

    Sharma, Charu; Sadek, Bassem; Goyal, Sameer N; Sinha, Satyesh; Kamal, Mohammad Amjad; Ojha, Shreesh

    2015-01-01

    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 Δ(9)-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. PMID:26664449

  11. 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.

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

    Science.gov (United States)

    Sharma, Charu; Sadek, Bassem; Goyal, Sameer N.; Sinha, Satyesh; Ojha, Shreesh

    2015-01-01

    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. PMID:26664449

  13. 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

  14. Principles of agonist recognition in Cys-loop receptors

    Directory of Open Access Journals (Sweden)

    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.

  15. In silico discovery of novel Retinoic Acid Receptor agonist structures

    Directory of Open Access Journals (Sweden)

    Samuels Herbert H

    2001-06-01

    Full Text Available Abstract Background Several Retinoic Acid Receptors (RAR agonists have therapeutic activity against a variety of cancer types; however, unacceptable toxicity profiles have hindered the development of drugs. RAR agonists presenting novel structural and chemical features could therefore open new avenues for the discovery of leads against breast, lung and prostate cancer or leukemia. Results We have analysed the induced fit of the active site residues upon binding of a known ligand. The derived binding site models were used to dock over 150,000 molecules in silico (or virtually to the structure of the receptor with the Internal Coordinates Mechanics (ICM program. Thirty ligand candidates were tested in vitro. Conclusions Two novel agonists resulting from the predicted receptor model were active at 50 nM. One of them displays novel structural features which may translate into the development of new ligands for cancer therapy.

  16. 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...... 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...

  17. The extracellular regulated kinases (ERK) 1/2 mediate cannabinoid-induced inhibition of gap junctional communication in endothelial cells

    OpenAIRE

    Brandes, R P; Popp, R; G. Ott; Bredenkötter, D; Wallner, C.; Busse, R.; Fleming, I.

    2002-01-01

    Cannabinoids are potent inhibitors of endothelium-derived hyperpolarizing factor (EDHF)-mediated relaxations. We set out to study the mechanism underlying this effect and the possible role of cannabinoid-induced changes in intercellular gap junction communication.In cultured endothelial cells, Δ9-tetrahydrocannabinol (Δ9-THC) and the cannabinoid receptor agonist HU210, increased the phosphorylation of extracellular regulated kinases 1/2 (ERK1/2) and inhibited gap junctional communication, as ...

  18. 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

  19. Cannabinoid CB1 receptor inhibition decreases vascular smooth muscle migration and proliferation

    International Nuclear Information System (INIS)

    Vascular smooth muscle proliferation and migration triggered by inflammatory stimuli and chemoattractants such as platelet-derived growth factor (PDGF) are key events in the development and progression of atherosclerosis and restenosis. Cannabinoids may modulate cell proliferation and migration in various cell types through cannabinoid receptors. Here we investigated the effects of CB1 receptor antagonist rimonabant (SR141716A), which has recently been shown to have anti-atherosclerotic effects both in mice and humans, on PDGF-induced proliferation, migration, and signal transduction of human coronary artery smooth muscle cells (HCASMCs). PDGF induced Ras and ERK 1/2 activation, while increasing proliferation and migration of HCASMCs, which were dose dependently attenuated by CB1 antagonist, rimonabant. These findings suggest that in addition to improving plasma lipid alterations and decreasing inflammatory cell migration and inflammatory response, CB1 antagonists may exert beneficial effects in atherosclerosis and restenosis by decreasing vascular smooth muscle proliferation and migration.

  20. 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.

  1. 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

  2. The actions of some cannabinoid receptor ligands in the rat isolated mesenteric artery

    OpenAIRE

    White, Richard; Robin Hiley, C

    1998-01-01

    The actions of a number of cannabinoid receptor ligands were investigated using the myograph-mounted rat isolated mesenteric artery. Anandamide, CP 55,940, HU-210, palmitoylethanolamide and WIN 55,212-2 all caused concentration-dependent relaxations of methoxamine-precontracted vessels which were not affected by removal of the endothelium.Precontracting vessels with 60 mM KCl instead of methoxamine greatly reduced the vasorelaxant effects of anandamide and palmitoylethanolamide. High K+ solut...

  3. Elevated Brain Cannabinoid CB1 Receptor Availability in Posttraumatic Stress Disorder: A Positron Emission Tomography Study

    OpenAIRE

    Neumeister, Alexander; Normandin, Marc D.; Pietrzak, Robert H.; Piomelli, Daniele; Zheng, Ming-Qiang; Gujarro-Anton, Ana; Potenza, Marc N.; Bailey, Christopher R.; Lin, Shu-fei; Najafzadeh, Soheila; Ropchan, Jim; Henry, Shannan; Corsi-Travali, Stefani; Carson, Richard E; Huang, Yiyun

    2013-01-01

    Endocannabinoids and their attending cannabinoid type 1 receptor (CB1) have been implicated in animal models of posttraumatic stress disorder (PTSD). However, their specific role has not been studied in people with PTSD. Herein, we present an in vivo imaging study using positron emission tomography (PET) and the CB1-selective radioligand [11C]OMAR in individuals with PTSD, and healthy controls with lifetime histories of trauma (trauma controls [TC]) and those without such histories (healthy c...

  4. Cannabis reinforcement and dependence: role of the cannabinoid CB1 receptor

    OpenAIRE

    Cooper, Ziva D; Haney, Margaret

    2008-01-01

    Awareness of cannabis dependence as a clinically relevant issue has grown in recent years. Clinical and laboratory studies demonstrate that chronic marijuana smokers can experience withdrawal symptoms upon cessation of marijuana smoking and have difficulty abstaining from marijuana use. This paper will review data implicating the cannabinoid CB1 receptor in regulating the behavioral effects of Δ9-tetrahydrocannobinol (THC), the primary psycho-active component of cannabis, across a range of sp...

  5. 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

  6. 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.

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

    Science.gov (United States)

    Bouskila, Joseph; Harrar, Vanessa; Javadi, Pasha; Beierschmitt, Amy; Palmour, Roberta; Casanova, Christian; Bouchard, Jean-François; Ptito, Maurice

    2016-01-01

    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. PMID:27069692

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

    Directory of Open Access Journals (Sweden)

    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.

  9. 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

  10. 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-(benzylox...

  11. 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 was to...

  12. 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.

  13. 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

  14. 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

  15. 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

  16. Failure to extinguish fear and genetic variability in the human cannabinoid receptor 1.

    Science.gov (United States)

    Heitland, I; Klumpers, F; Oosting, R S; Evers, D J J; Leon Kenemans, J; Baas, J M P

    2012-01-01

    Failure to extinguish fear can lead to persevering anxiety and has been postulated as an important mechanism in the pathogenesis of human anxiety disorders. In animals, it is well documented that the endogenous cannabinoid system has a pivotal role in the successful extinction of fear, most importantly through the cannabinoid receptor 1. However, no human studies have reported a translation of this preclinical evidence yet. Healthy medication-free human subjects (N=150) underwent a fear conditioning and extinction procedure in a virtual reality environment. Fear potentiation of the eyeblink startle reflex was measured to assess fear-conditioned responding, and subjective fear ratings were collected. Participants were genotyped for two polymorphisms located within the promoter region (rs2180619) and the coding region (rs1049353) of cannabinoid receptor 1. As predicted from the preclinical literature, acquisition and expression of conditioned fear did not differ between genotypes. Crucially, whereas both homozygote (G/G, N=23) and heterozygote (A/G, N=68) G-allele carriers of rs2180619 displayed robust extinction of fear, extinction of fear-potentiated startle was absent in A/A homozygotes (N=51). Additionally, this resistance to extinguish fear left A/A carriers of rs2180619 with significantly higher levels of fear-potentiated startle at the end of the extinction training. No effects of rs1049353 genotype were observed regarding fear acquisition and extinction. These results suggest for the first time involvement of the human endocannabinoid system in fear extinction. Implications are that genetic variability in this system may underlie individual differences in anxiety, rendering cannabinoid receptor 1 a potential target for novel pharmacological treatments of anxiety disorders. PMID:23010766

  17. GABAA receptor partial agonists and antagonists

    DEFF Research Database (Denmark)

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

    2015-01-01

    A high degree of structural heterogeneity of the GABAA receptors (GABAARs) has been revealed and is reflected in multiple receptor subtypes. The subunit composition of GABAAR subtypes is believed to determine their localization relative to the synapses and adapt their functional properties to the...... antagonists have been essential in defining the tonic current but both remaining issues concerning the GABAARs involved and the therapeutic possibilities of modulating tonic inhibition underline the need for GABAAR antagonists with improved selectivity....

  18. Cannabinoids and Dementia: A Review of Clinical and Preclinical Data

    Directory of Open Access Journals (Sweden)

    Michael Halpern

    2010-08-01

    Full Text Available The endocannabinoid system has been shown to be associated with neurodegenerative diseases and dementia. We review the preclinical and clinical data on cannabinoids and four neurodegenerative diseases: Alzheimer’s disease (AD, Huntington’s disease (HD, Parkinson’s disease (PD and vascular dementia (VD. Numerous studies have demonstrated an involvement of the cannabinoid system in neurotransmission, neuropathology and neurobiology of dementias. In addition, several candidate compounds have demonstrated efficacy in vitro. However, some of the substances produced inconclusive results in vivo. Therefore, only few trials have aimed to replicate the effects seen in animal studies in patients. Indeed, the literature on cannabinoid administration in patients is scarce. While preclinical findings suggest causal treatment strategies involving cannabinoids, clinical trials have only assessed the suitability of cannabinoid receptor agonists, antagonists and cannabidiol for the symptomatic treatment of dementia. Further research is needed, including in vivo models of dementia and human studies.

  19. Cannabinoid CB1 receptor and endothelium-dependent hyperpolarization in guinea-pig carotid, rat mesenteric and porcine coronary arteries

    OpenAIRE

    Chataigneau, T; Félétou, M; Thollon, C; N. Villeneuve; Vilaine, J- P; Duhault, J; Vanhoutte, P M

    1998-01-01

    The purpose of these experiments was to determine whether or not the endothelium-dependent hyperpolarizations of the vascular smooth muscle cells (observed in the presence of inhibitors of nitric oxide synthase and cyclo-oxygenase) can be attributed to the production of an endogenous cannabinoid.Membrane potential was recorded in the guinea-pig carotid, rat mesenteric and porcine coronary arteries by intracellular microelectrodes.In the rat mesenteric artery, the cannabinoid receptor antagoni...

  20. 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...

  1. Mapping the Structural Requirements in the CB1 Cannabinoid Receptor Transmembrane Helix II for Signal Transduction

    OpenAIRE

    Kapur, Ankur; Samaniego, Patrick; Thakur, Ganesh A.; Makriyannis, Alexandros; Abood, Mary E.

    2008-01-01

    Amino acid residues in the transmembrane domains of the CB1 receptor are important for ligand recognition and signal transduction. We used site-directed mutagenesis to identify the role of two novel and adjacent residues in the transmembrane helix II domain, Ile2.62 and Asp2.63. We investigated the role of the conserved, negatively charged aspartate at position 2.63 in cannabinoid receptor (CB1) function by substituting it with asparagine (D2.63N) and glutamate (D2.63E). In addition, the effe...

  2. Cannabinoid CB1 receptors fail to cause relaxation, but couple via Gi/Go to the inhibition of adenylyl cyclase in carotid artery smooth muscle

    OpenAIRE

    Holland, Michael; Challiss, R. A. John; Standen, Nicholas B.; Boyle, John P

    1999-01-01

    The aim of the current study was to characterize which cannabinoid receptors, if any, are present on rat carotid artery smooth muscle. Additionally, the effects of cannabinoids on carotid artery tone, on cyclic AMP accumulation and on forskolin-induced relaxation were examined in the same tissue.Stimulation of carotid arteries with forskolin (10 μM) significantly increased cyclic AMP accumulation, an effect that was inhibited in a concentration-dependent manner by the cannabinoid receptor ago...

  3. 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....

  4. On the role of cannabinoid CB1- and µ-opioid receptors in nicotine-induced motor impulsivity

    Directory of Open Access Journals (Sweden)

    TommyPattij

    2012-06-01

    Full Text Available Previous studies using a rat 5-choice serial reaction time task (5-CSRTT have established a critical role for dopamine D2 receptors in regulating increments in motor impulsivity induced by acute administration of the psychostimulant drugs amphetamine and nicotine. Here we investigated whether cannabinoid CB1 and/or µ-opioid receptors are involved in nicotine-induced impulsivity, given recent findings indicating that both receptor systems mediate amphetamine-induced motor impulsivity. Results showed that the cannabinoid CB1 receptor antagonist SR141716A, but not the opioid receptor antagonist naloxone, reduced nicotine-induced premature responding. In contrast, SR141716A did not affect impulsivity following a challenge with the dopamine transporter inhibitor GBR 12909, a form of drug-induced impulsivity that was previously found to be dependent on µ-opioid receptor activation. Finally, unlike SR141716A and the dopamine D2 receptor antagonist eticlopride, naloxone did not affect impulsivity when the intertrial interval was lengthened from 5 to 7s, i.e. under conditions of heightened cognitive load resulting in higher levels of premature responding. Together, these findings indicate that nicotine-induced motor impulsivity is cannabinoid, but not opioid receptor-dependent. These data confirm that the endogenous cannabinoid, dopamine, and opioid systems each play important, but distinct roles in regulating motor impulsivity. The rather complex interplay between these neurotransmitter systems modulating impulsivity will be discussed in terms of the differential involvement of mesocortical and mesolimbic neurocircuitry.

  5. Normal aging in rats and pathological aging in human Alzheimer's disease decrease FAAH activity: modulation by cannabinoid agonists.

    Science.gov (United States)

    Pascual, A C; Martín-Moreno, A M; Giusto, N M; de Ceballos, M L; Pasquaré, S J

    2014-12-01

    Anandamide is an endocannabinoid involved in several physiological functions including neuroprotection. Anandamide is synthesized on demand and its endogenous level is regulated through its degradation, where fatty acid amide hydrolase plays a major role. The aim of this study was to characterize anandamide breakdown in physiological and pathological aging and its regulation by CB1 and CB2 receptor agonists. Fatty acid amide hydrolase activity was analyzed in an independent cohort of human cortical membrane samples from control and Alzheimer's disease patients, and in membrane and synaptosomes from adult and aged rat cerebral cortex. Our results demonstrate that fatty acid amide hydrolase activity decreases in the frontal cortex from human patients with Alzheimer's disease and this effect is mimicked by Aβ(1-40) peptide. This activity increases and decreases in aged rat cerebrocortical membranes and synaptosomes, respectively. Also, while the presence of JWH-133, a CB2 selective agonist, slightly increases anandamide hydrolysis in human controls, it decreases this activity in adults and aged rat cerebrocortical membranes and synaptosomes. In the presence of WIN55,212-2, a mixed CB1/CB2 agonist, anandamide hydrolysis increases in Alzheimer's disease patients but decreases in human controls as well as in adult and aged rat cerebrocortical membranes and synaptosomes. Although a similar profile is observed in fatty acid amide hydrolase activity between aged rat synaptic endings and human Alzheimer's disease brains, it is differently modulated by CB1/CB2 agonists. This modulation leads to a reduced availability of anandamide in Alzheimer's disease and to an increased availability of this endocannabinoid in aging. PMID:25456842

  6. 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.

  7. 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...

  8. Improving the developability profile of pyrrolidine progesterone receptor partial agonists

    Energy Technology Data Exchange (ETDEWEB)

    Kallander, Lara S.; Washburn, David G.; Hoang, Tram H.; Frazee, James S.; Stoy, Patrick; Johnson, Latisha; Lu, Qing; Hammond, Marlys; Barton, Linda S.; Patterson, Jaclyn R.; Azzarano, Leonard M.; Nagilla, Rakesh; Madauss, Kevin P.; Williams, Shawn P.; Stewart, Eugene L.; Duraiswami, Chaya; Grygielko, Eugene T.; Xu, Xiaoping; Laping, Nicholas J.; Bray, Jeffrey D.; Thompson, Scott K. (GSKPA)

    2010-09-17

    The previously reported pyrrolidine class of progesterone receptor partial agonists demonstrated excellent potency but suffered from serious liabilities including hERG blockade and high volume of distribution in the rat. The basic pyrrolidine amine was intentionally converted to a sulfonamide, carbamate, or amide to address these liabilities. The evaluation of the degree of partial agonism for these non-basic pyrrolidine derivatives and demonstration of their efficacy in an in vivo model of endometriosis is disclosed herein.

  9. Synthesis of fluorinated agonist of sphingosine-1-phosphate receptor 1.

    Science.gov (United States)

    Aliouane, Lucie; Chao, Sovy; Brizuela, Leyre; Pfund, Emmanuel; Cuvillier, Olivier; Jean, Ludovic; Renard, Pierre-Yves; Lequeux, Thierry

    2014-09-01

    The bioactive metabolite sphingosine-1-phosphate (S1P), a product of sphingosine kinases (SphKs), mediates diverse biological processes such as cell differentiation, proliferation, survival and angiogenesis. A fluorinated analogue of S1P receptor agonist has been synthesized by utilizing a ring opening reaction of oxacycles by a lithiated difluoromethylphosphonate anion as the key reaction. In vitro activity of this S1P analogue is also reported. PMID:25047939

  10. 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.

  11. 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

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

    International Nuclear Information System (INIS)

    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

  13. 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

  14. Ramelteon: A melatonin receptor agonist for the treatment of insomnia

    Directory of Open Access Journals (Sweden)

    Devi V

    2008-01-01

    Full Text Available Ramelteon is a novel MT1 and MT2 melatonin receptor selective agonist recently approved for the treatment of insomnia characterized by difficulty in sleep onset. It is a nonscheduled drug since it lacks the potential for abuse and does not interact with neurotransmitter receptors most associated with these phenomena. Although the effects of ramelteon use> 5 weeks are unknown, the available data confirms its safety and efficacy for short-term use. Clinical use and future research should uncover more information about ramelteon′s properties.

  15. Principles of agonist recognition in Cys-loop receptors

    DEFF Research Database (Denmark)

    Lynagh, Timothy Peter; Pless, Stephan Alexander

    2014-01-01

    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......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...

  16. SGIP1 alters internalization and modulates signaling of activated cannabinoid receptor 1 in a biased manner.

    Science.gov (United States)

    Hájková, Alena; Techlovská, Šárka; Dvořáková, Michaela; Chambers, Jayne Nicole; Kumpošt, Jiří; Hubálková, Pavla; Prezeau, Laurent; Blahos, Jaroslav

    2016-08-01

    Many diseases of the nervous system are accompanied by alterations in synaptic functions. Synaptic plasticity mediated by the endogenous cannabinoid system involves the activation of the cannabinoid receptor 1 (CB1R). The principles of CB1R signaling must be understood in detail for its therapeutic exploration. We detected the Src homology 3-domain growth factor receptor-bound 2-like (endophilin) interacting protein 1 (SGIP1) as a novel CB1R partner. SGIP1 is functionally linked to clathrin-mediated endocytosis and its overexpression in animals leads to an energy regulation imbalance resulting in obesity. We report that SGIP1 prevents the endocytosis of activated CB1R and that it alters signaling via the CB1R in a biased manner. CB1R mediated G-protein activation is selectively influenced by SGIP1, β-arrestin associated signaling is changed profoundly, most likely as a consequence of the prevention of the receptor's internalization elicited by SGIP1. PMID:26970018

  17. Distribution of CB1 cannabinoid receptors in the rat amygdaloid complex

    Directory of Open Access Journals (Sweden)

    Puškaš Laslo A.

    2004-01-01

    Full Text Available The amygdaloid complex (AK has a very important role in the modulation of endocrine and visceral functions, in complex behavioral mechanisms such as defense, feeding, aggression, affects, reproduction, memory and learning. The aim of this study was to determine the precise distribution of cannabinoid CB1 receptors in the rat AK, using the immunohistochemical (ABC method. According to our results, CB1-immunoreactivity in the rat AK was highest in the medial nucleus. Slightly lower immunoreactivity was found in the basolateral nucleus. Moderate density of CB1 receptors occurred in the central, basomedial, lateral and posterior nuclei of the AK. CB1-immunoreactivity in all of these nuclei was present in the form of discrete spot-like precipitates of unequal size and appearance. These precipitates exhibited three different patterns: 1. elongated columns or lines, 2. complete or incomplete rings and 3. in a small number of AK regions CB1-immunoreactivity was separately dispersed in the form of single spot-like precipitates between more complex columns and rings of precipitates. Considering the functional importance of amygdala and the distribution of CB1 receptors in the AK we could conclude that our findings suggest a role for cannabinoids in modulating responses of the AK to stress and fear as well as to pain.

  18. 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. PMID:26410677

  19. 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.

  20. The Antitumor Activity of Plant-Derived Non-Psychoactive Cannabinoids.

    Science.gov (United States)

    McAllister, Sean D; Soroceanu, Liliana; Desprez, Pierre-Yves

    2015-06-01

    As a therapeutic agent, most people are familiar with the palliative effects of the primary psychoactive constituent of Cannabis sativa (CS), Δ(9)-tetrahydrocannabinol (THC), a molecule active at both the cannabinoid 1 (CB1) and cannabinoid 2 (CB2) receptor subtypes. Through the activation primarily of CB1 receptors in the central nervous system, THC can reduce nausea, emesis and pain in cancer patients undergoing chemotherapy. During the last decade, however, several studies have now shown that CB1 and CB2 receptor agonists can act as direct antitumor agents in a variety of aggressive cancers. In addition to THC, there are many other cannabinoids found in CS, and a majority produces little to no psychoactivity due to the inability to activate cannabinoid receptors. For example, the second most abundant cannabinoid in CS is the non-psychoactive cannabidiol (CBD). Using animal models, CBD has been shown to inhibit the progression of many types of cancer including glioblastoma (GBM), breast, lung, prostate and colon cancer. This review will center on mechanisms by which CBD, and other plant-derived cannabinoids inefficient at activating cannabinoid receptors, inhibit tumor cell viability, invasion, metastasis, angiogenesis, and the stem-like potential of cancer cells. We will also discuss the ability of non-psychoactive cannabinoids to induce autophagy and apoptotic-mediated cancer cell death, and enhance the activity of first-line agents commonly used in cancer treatment. PMID:25916739

  1. 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.

  2. 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

  3. 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

  4. 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.

  5. 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

  6. Characterisation of the cannabinoid receptor system in synovial tissue and fluid in patients with osteoarthritis and rheumatoid arthritis

    OpenAIRE

    Richardson, Denise; Pearson, Richard G; Kurian, Nisha; Latif, M. Liaque; Garle, Michael J; Barrett, David A; Kendall, David A; Scammell, Brigitte E; Reeve, Alison J; Chapman, Victoria

    2008-01-01

    Introduction Cannabis-based medicines have a number of therapeutic indications, including anti-inflammatory and analgesic effects. The endocannabinoid receptor system, including the cannabinoid receptor 1 (CB1) and receptor 2 (CB2) and the endocannabinoids, are implicated in a wide range of physiological and pathophysiological processes. Pre-clinical and clinical studies have demonstrated that cannabis-based drugs have therapeutic potential in inflammatory diseases, including rheumatoid arthr...

  7. On the role of cannabinoid CB1- and µ-opioid receptors in nicotine-induced motor impulsivity

    OpenAIRE

    TommyPattij

    2012-01-01

    Previous studies using a rat 5-choice serial reaction time task (5-CSRTT) have established a critical role for dopamine D2 receptors in regulating increments in motor impulsivity induced by acute administration of the psychostimulant drugs amphetamine and nicotine. Here we investigated whether cannabinoid CB1 and/or µ-opioid receptors are involved in nicotine-induced impulsivity, given recent findings indicating that both receptor systems mediate amphetamine-induced motor impulsivity. Re...

  8. GABA(A) receptors in the central amygdala are involved in memory retention deficits induced by cannabinoids in rats.

    Science.gov (United States)

    Hasanein, Parisa; Sharifi, Maryam

    2015-11-01

    The central nucleus of the amygdala (CeA) as the main output of amygdala plays an important role in memory processes. In this study we first evaluated the effects of intra-CeA administrations of different doses of a cannabinoid CB1 agonist, WIN55, 212-2, GABA(A) receptor agonist and antagonist, muscimol and bicuculline, alone on memory retention using passive avoidance learning (PAL) test in rats. Then we examined the effects of GABA(A) receptor agents on the responses induced by intra-CeA microinjection of different doses of WIN55, 212-2. We found that administration of WIN55, 212-2 (0.05, 0.1, 0.2 and 0.4μg/rat) immediately after training impaired memory retrieval in a dose-dependent fashion. Although pre-test intra-CeA administration of muscimol (125, 250 and 500ng/rat) alone had no effect on the step-through latency, its co-administration (125ng/rat) with different doses of WIN55, 212-2 potentiated the amnesic effects of any doses of WIN55, 212-2. The results also showed that pre-test intra-CeA administration of bicuculline (200, 400 and 800ng/rat) alone had no significant effect, but at dose of 200ng/rat disrupted post-training WIN55, 212-2-induced amnesia in the retention test. Furthermore, the additional effect of muscimol (125ng/rat) on memory impairment induced by WIN55, 212-2 (0.1μg/rat) was prevented by intra-CeA co-injection of bicuculline (200ng/rat). We indicated that stimulating or blocking GAGA(A) receptors in the CeA by muscimol and bicuculline interfere with WIN55, 212-2-induced deficits in memory retention in a PAL task and therefore suggests an interaction between cannabinergic and GABAergic systems of the CeA in memory process. PMID:26368844

  9. 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....

  10. 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

  11. 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...

  12. 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

  13. 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...

  14. The periaqueductal gray contributes to bidirectional enhancement of antinociception between morphine and cannabinoids

    OpenAIRE

    Wilson-Poe, Adrianne R.; Pocius, Edvinas; Herschbach, Melissa; Morgan, Michael M

    2012-01-01

    Co-administration of opioids and cannabinoids can enhance pain relief even when administered on different days. Repeated systemic administration of morphine has been shown to enhance the antinociceptive effect of tetrahydrocannbinol (THC) administered 12 hours later, and repeated microinjection of the cannabinoid receptor agonist HU-210 into the ventrolateral periaqueductal gray (PAG) has been shown to enhance the antinociceptive effect of morphine administered one day later. The primary obje...

  15. Antinociceptive properties of selective MT(2) melatonin receptor partial agonists.

    Science.gov (United States)

    López-Canul, Martha; Comai, Stefano; Domínguez-López, Sergio; Granados-Soto, Vinicio; Gobbi, Gabriella

    2015-10-01

    Melatonin is a neurohormone involved in the regulation of both acute and chronic pain whose mechanism is still not completely understood. We have recently demonstrated that selective MT2 melatonin receptor partial agonists have antiallodynic properties in animal models of chronic neuropathic pain by modulating ON/OFF cells of the descending antinociceptive system. Here, we examined the antinociceptive properties of the selective MT2 melatonin receptor partial agonists N-{2-[(3-methoxyphenyl)phenylamino]ethyl}acetamide (UCM765) and N-{2-[(3-bromophenyl)-(4-fluorophenyl)amino]ethyl}acetamide (UCM924) in two animal models of acute and inflammatory pain: the hot-plate and formalin tests. UCM765 and UCM924 (5-40 mg/kg, s.c.) dose-dependently increased the temperature of the first hind paw lick in the hot-plate test, and decreased the total time spent licking the injected hind paw in the formalin test. Antinociceptive effects of UCM765 and UCM924 were maximal at the dose of 20mg/kg. At this dose, the effects of UCM765 and UCM924 were similar to those produced by 200 mg/kg acetaminophen in the hot-plate test, and by 3 mg/kg ketorolac or 150 mg/kg MLT in the formalin test. Notably, antinociceptive effects of the two MT2 partial agonists were blocked by the pre-treatment with the MT2 antagonist 4-phenyl-2-propionamidotetralin (4P-PDOT, 10 mg/kg) in both paradigms. These results demonstrate the antinociceptive properties of UCM765 and UCM924 in acute and inflammatory pain models and corroborate the concept that MT2 melatonin receptor may be a novel target for analgesic drug development. PMID:26162699

  16. 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

  17. Antidepressant-like effects of the cannabinoid receptor ligands in the forced swimming test in mice: mechanism of action and possible interactions with cholinergic system.

    Science.gov (United States)

    Kruk-Slomka, Marta; Michalak, Agnieszka; Biala, Grazyna

    2015-05-01

    The purpose of the experiments was to explore the role of the endocannabinoid system, through cannabinoid (CB) receptor ligands, nicotine and scopolamine, in the depression-related responses using the forced swimming test (FST) in mice. Our results revealed that acute injection of oleamide (10 and 20 mg/kg), a CB1 receptor agonist, caused antidepressant-like effect in the FST, while AM 251 (0.25-3 mg/kg), a CB1 receptor antagonist, did not provoke any effect in this test. Moreover, acute administration of both CB2 receptor agonist, JWH 133 (0.5 and 1 mg/kg) and CB2 receptor antagonist, AM 630 (0.5 mg/kg), exhibited antidepressant action. Antidepressant effects of oleamide and JWH 133 were attenuated by acute injection of both non-effective dose of AM 251, as well as AM 630. Among the all CB compounds used, only the combination of non-effective dose of oleamide (2.5 mg/kg) with non-effective dose of nicotine (0.5 mg/kg) caused an antidepressant effect. However, none of the CB receptor ligands, had influence on the antidepressant effects provoked by nicotine (0.2 mg/kg) injection. In turn, the combination of non-effective dose of oleamide (2.5 mg/kg); JWH (2 mg/kg) or AM 630 (2 mg/kg), but not of AM 251 (0.25 mg/kg), with non-effective dose of scopolamine (0.1 mg/kg), exhibited antidepressant properties. Indeed, all of the CB compounds used, intensified the antidepressant-like effects induced by an acute injection of scopolamine (0.3 mg/kg). Our results provide clear evidence that the endocannabinoid system participates in the depression-related behavior and through interactions with cholinergic system modulate these kind of responses. PMID:25660201

  18. 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

  19. 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

  20. GABA(A) receptor density is altered by cannabinoid treatment in the hippocampus of adult but not adolescent rats.

    Science.gov (United States)

    Verdurand, Mathieu; Dalton, Victoria Stephanie; Zavitsanou, Katerina

    2010-09-10

    Cannabinoids are known to induce transient psychotic symptoms and cognitive dysfunction in healthy individuals and contribute to trigger schizophrenia in vulnerable individuals, particularly during adolescence. Converging preclinical evidence suggests important interactions between cannabinoid and GABAergic systems. In the present study, we compared the effects of cannabinoid treatment on GABA(A) receptor binding in the brain of adolescent and adult rats. Adolescent (5 weeks old) and adult (10 weeks old) rats were treated with the synthetic cannabinoid HU210 (25, 50 or 100 microg/kg/day) or vehicle for 1, 4 or 14 days. Rats were sacrificed 24 h after the last injection and GABA(A) receptor density was measured in several brain regions using [(35)S]TBPS and in vitro autoradiography. Adolescent rats had higher numbers of GABA(A) receptors compared to adults. A 24% increase of binding in adult rats treated with 100 microg/kg HU210 for 14 days compared to controls was observed in the CA1 region of the hippocampus (16.1 versus 12.9 fmol/mg tissue equivalent, t=2.720, pHU210 did not affect GABA(A) receptors in adolescent rats in any treatment regimen and in adult rats treated with HU210 for 1 or 4 days. These data suggest that long-term, high-dose treatment with HU210 increases GABA(A) receptors in the hippocampus of adult rats, changes that may interfere with associated hippocampal cognitive functions such as learning and memory. In addition, our results suggest that the adolescent brain does not display the same compensatory mechanisms that are activated in the adult brain following cannabinoid treatment. PMID:20599838

  1. 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...

  2. The CB1 cannabinoid receptor drives corticospinal motor neuron differentiation through the Ctip2/Satb2 transcriptional regulation axis

    OpenAIRE

    Díaz-Alonso, Javier; Aguado, Tania; Wu, Chia-Shan; Palazuelos, Javier; Hofmann, Clementine; Garcez, Patricia; Guillemot, Francois; Lu, Hui-Chen; Lutz, Beat; Guzmán, Manuel; Galve-Roperh, Ismael

    2012-01-01

    The generation and specification of pyramidal neuron subpopulations during development relies on a complex network of transcription factors. The CB1 cannabinoid receptor is the major molecular target of endocannabinoids and marijuana active compounds. This receptor has been shown to influence neural progenitor proliferation and axonal growth, but its involvement in neuronal differentiation and the functional impact in the adulthood caused by altering its signaling during brain development are...

  3. 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

  4. 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

  5. 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

  6. 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

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

    Science.gov (United States)

    Cécyre, Bruno; Thomas, Sébastien; Ptito, Maurice; Casanova, Christian; Bouchard, Jean-François

    2014-02-01

    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, CB2R has traditionally been associated to the immune system. This dogma is currently a subject of debate since the discovery of CB2R expression in neurons using antibody-based methods. The localization of CB2R in the central nervous system (CNS) could have a significant impact on drug development because it would mean that in addition to its effects on the peripheral pain pathway, CB2R could also mediate some central effects of cannabinoids. In an attempt to clarify the debate over CB2R expression in the CNS, we tested several commercially or academically produced CB2R antibodies using Western blot and immunohistochemistry on retinal tissue obtained from wild-type mice and mice lacking CB2R (cnr2 (-/-) ). One of the antibodies tested exhibited a valuable specificity as it marked a single band near the predicted molecular weight in Western blot and produced no staining in cnr2 (-/-) mice retina sections. The other antibodies tested detected multiple bands in Western blot and labeled unidentified proteins when used with their immunizing peptide or on cnr2 (-/-) retinal sections. We conclude that many commonly used antibodies raised against CB2R are not specific for use in immunohistochemistry, at least in the context of the mouse retina. Moreover, some of them tested presented significant lot-to-lot variability. Hence, caution should be used when interpreting prior and future studies using CB2R antibodies. PMID:24185999

  8. Cannabinoid receptor-specific mechanisms to alleviate pain in sickle cell anemia via inhibition of mast cell activation and neurogenic inflammation.

    Science.gov (United States)

    Vincent, Lucile; Vang, Derek; Nguyen, Julia; Benson, Barbara; Lei, Jianxun; Gupta, Kalpna

    2016-05-01

    Sickle cell anemia is a manifestation of a single point mutation in hemoglobin, but inflammation and pain are the insignia of this disease which can start in infancy and continue throughout life. Earlier studies showed that mast cell activation contributes to neurogenic inflammation and pain in sickle mice. Morphine is the common analgesic treatment but also remains a major challenge due to its side effects and ability to activate mast cells. We, therefore, examined cannabinoid receptor-specific mechanisms to mitigate mast cell activation, neurogenic inflammation and hyperalgesia, using HbSS-BERK sickle and cannabinoid receptor-2-deleted sickle mice. We show that cannabinoids mitigate mast cell activation, inflammation and neurogenic inflammation in sickle mice via both cannabinoid receptors 1 and 2. Thus, cannabinoids influence systemic and neural mechanisms, ameliorating the disease pathobiology and hyperalgesia in sickle mice. This study provides 'proof of principle' for the potential of cannabinoid/cannabinoid receptor-based therapeutics to treat several manifestations of sickle cell anemia. PMID:26703965

  9. 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...

  10. Proteasome involvement in agonist-induced down-regulation of mu and delta opioid receptors.

    Science.gov (United States)

    Chaturvedi, K; Bandari, P; Chinen, N; Howells, R D

    2001-04-13

    This study investigated the mechanism of agonist-induced opioid receptor down-regulation. Incubation of HEK 293 cells expressing FLAG-tagged delta and mu receptors with agonists caused a time-dependent decrease in opioid receptor levels assayed by immunoblotting. Pulse-chase experiments using [(35)S]methionine metabolic labeling indicated that the turnover rate of delta receptors was accelerated 5-fold following agonist stimulation. Inactivation of functional G(i) and G(o) proteins by pertussis toxin-attenuated down-regulation of the mu opioid receptor, while down-regulation of the delta opioid receptor was unaffected. Pretreatment of cells with inhibitors of lysosomal proteases, calpain, and caspases had little effect on mu and delta opioid receptor down-regulation. In marked contrast, pretreatment with proteasome inhibitors attenuated agonist-induced mu and delta receptor down-regulation. In addition, incubation of cells with proteasome inhibitors in the absence of agonists increased steady-state mu and delta opioid receptor levels. Immunoprecipitation of mu and delta opioid receptors followed by immunoblotting with ubiquitin antibodies suggested that preincubation with proteasome inhibitors promoted accumulation of polyubiquitinated receptors. These data provide evidence that the ubiquitin/proteasome pathway plays a role in agonist-induced down-regulation and basal turnover of opioid receptors. PMID:11152677

  11. 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.

  12. Thrombopoietin-receptor agonists in haematological disorders: The Danish experience

    DEFF Research Database (Denmark)

    Gudbrandsdottir, Sif; Frederiksen, Henrik; Hasselbalch, Hans

    2011-01-01

    received TPO-ra from 2009 to 1 May 2011 were available for data collection and included in the study. Of these patients, 15 received TPO-ra for refractory primary ITP, 7 for secondary ITP (chronic lymphatic leukaemia, systemic lupus erythematosus, Evans syndrome, human immunodeficiency virus and celiac......The objective of this study was to investigate the use of thrombopoietin-receptor agonists (TPO-ra) in patients with refractory primary immune thrombocytopenia (ITP) as well as off-label use of TPO-ra in Danish haematology departments. Hospital medical records from 32 of the 39 patients having...... primary ITP patients, 57% of patients with secondary ITP and 40% of patients with non-ITP. There were four deaths in the cohort, three of which were related to pre-existing medical conditions. Otherwise adverse effects were in general mild. This Danish retrospective registration study has demonstrated...

  13. Pharmacophore Pattern Identification of Tachykinin Receptor Selective Peptide Agonists: Implications in Receptor Selectivity

    Directory of Open Access Journals (Sweden)

    Anjali Dike

    2007-01-01

    Full Text Available The mammalian tachykinin (TK peptides and their three Neurokinin (NK1, NK2 and NK3 receptors represent an effector system with wide-ranging actions on neuronal, airway smooth muscle, mucosal, endothelial, immune, inflammatory and remodeling cell function. Recent clinical and preclinical data suggests the pathophysiological role of TKs in various diseases including asthma, emesis and depression. The TK-NK receptor interactions and overlapping functions mediated by each NK receptor indicate added therapeutic benefit of using multiple NK receptor blockade. In the absence of structural data on neurokinin receptors, the membrane-induced structure of tachykinins play an important role as a first step towards understanding structure-activity relationship. A comparison of the conformational features of different NK1, NK2 and NK3 receptor agonists highlights several features which might be responsible for determining selectivity for the particular receptor subtype. An attempt has been made to correlate the observed conformational differences to the binding ability and biological activity of various NK1, NK2 and NK3 receptor agonists. The membrane bound conformations of tachykinins have been used as a starting point, leading to useful pharmacophore patterns that can be used for identifying lead structures with novel scaffolds.

  14. 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

  15. 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

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

    Directory of Open Access Journals (Sweden)

    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.

  17. Role of the Cannabinoid System in Pain Control and Therapeutic Implications for the Management of Acute and Chronic Pain Episodes

    OpenAIRE

    Manzanares, J.; Julian, MD; Carrascosa, A

    2006-01-01

    Cannabis extracts and synthetic cannabinoids are still widely considered illegal substances. Preclinical and clinical studies have suggested that they may result useful to treat diverse diseases, including those related with acute or chronic pain. The discovery of cannabinoid receptors, their endogenous ligands, and the machinery for the synthesis, transport, and degradation of these retrograde messengers, has equipped us with neurochemical tools for novel drug design. Agonist-activated canna...

  18. 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

  19. Mastering tricyclic ring systems for desirable functional cannabinoid activity

    Science.gov (United States)

    Petrov, Ravil R.; Knight, Lindsay; Chen, Shao-Rui; Wager-Miller, Jim; McDaniel, Steven W.; Diaz, Fanny; Barth, Francis; Pan, Hui-Lin; Mackie, Ken; Cavasotto, Claudio N.; Diaz, Philippe

    2013-01-01

    There is growing interest in using cannabinoid receptor 2 (CB2) agonists for the treatment of neuropathic pain and other indications. In continuation of our ongoing program aiming for the development of new small molecule cannabinoid ligands, we have synthesized a novel series of carbazole and γ-carboline derivatives. The affinities of the newly synthesized compounds were determined by a competitive radioligand displacement assay for human CB2 cannabinoid receptor and rat CB1 cannabinoid receptor. Functional activity and selectivity at human CB1 and CB2 receptors were characterized using receptor internalization and [35S]GTP-γ-S assays. The structure-activity relationship and optimization studies of the carbazole series have led to the discovery of a non-selective CB1 and CB2 agonist, compound 4. Our subsequent research efforts to increase CB2 selectivity of this lead compound have led to the discovery of CB2 selective compound 64, which robustly internalized CB2 receptors. Compound 64 had potent inhibitory effects on pain hypersensitivity in a rat model of neuropathic pain. Other potent and CB2 receptor–selective compounds, including compounds 63 and 68, and a selective CB1 agonist, compound 74 were also discovered. In addition, we identified the CB2 ligand 35 which failed to promote CB2 receptor internalization and inhibited compound CP55,940-induced CB2 internalization despite a high CB2 receptor affinity. The present study provides novel tricyclic series as a starting point for further investigations of CB2 pharmacology and pain treatment. PMID:24125850

  20. Agonists, antagonists and modulators of excitatory amino acid receptors in the guinea-pig myenteric plexus.

    OpenAIRE

    Luzzi, S; Zilletti, L.; S.Franchi-Micheli; Gori, A M; Moroni, F

    1988-01-01

    1. The receptors for glutamic acid (L-Glu) present in the guinea-pig myenteric plexus-ileal longitudinal muscle preparation have been studied by measuring the muscle contraction induced by numerous putative endogenous agonists acting at these receptors. Furthermore, the actions of different concentrations of antagonists, glycine, Mg2+ and Ca2+ on the ileal contractions induced by L-Glu have been evaluated. 2. The EC50 values of the most common putative endogenous agonists of these receptors w...

  1. Bisdemethoxycurcumin Induces Apoptosis in Activated Hepatic Stellate Cells via Cannabinoid Receptor 2

    Directory of Open Access Journals (Sweden)

    Phil Jun Lee

    2015-01-01

    Full Text Available Activated Hepatic Stellate Cells (HSCs, major fibrogenic cells in the liver, undergo apoptosis when liver injuries cease, which may contribute to the resolution of fibrosis. Bisdemethoxycurcumin (BDMC is a natural derivative of curcumin with anti-inflammatory and anti-cancer activities. The therapeutic potential of BDMC in hepatic fibrosis has not been studied thus far in the context of the apoptosis in activated HSCs. In the current study, we compared the activities of BDMC and curcumin in the HSC-T6 cell line and demonstrated that BDMC relatively induced a potent apoptosis. BDMC-induced apoptosis was mediated by a combinatory inhibition of cytoprotective proteins, such as Bcl2 and heme oxygenase-1 and increased generation of reactive oxygen species. Intriguingly, BDMC-induced apoptosis was reversed with co-treatment of sr144528, a cannabinoid receptor (CBR 2 antagonist, which was confirmed with genetic downregulation of the receptor using siCBR2. Additionally, incubation with BDMC increased the formation of death-induced signaling complex in HSC-T6 cells. Treatment with BDMC significantly diminished total intracellular ATP levels and upregulated ATP inhibitory factor-1. Collectively, the results demonstrate that BDMC induces apoptosis in activated HSCs, but not in hepatocytes, by impairing cellular energetics and causing a downregulation of cytoprotective proteins, likely through a mechanism that involves CBR2.

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

    Directory of Open Access Journals (Sweden)

    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.

  3. Cannabinoid CB1 receptor inhibition blunts adolescent-typical increased binge alcohol and sucrose consumption in male C57BL/6J mice

    Science.gov (United States)

    Agoglia, Abigail E.; Holstein, Sarah E.; Eastman, Vallari R.; Hodge, Clyde W.

    2016-01-01

    Increased binge alcohol consumption has been reported among adolescents as compared to adults in both humans and rodent models, and has been associated with serious long-term health consequences. However, the neurochemical mechanism for age differences in binge drinking between adolescents and adults has not been established. The present study was designed to evaluate the mechanistic role of the cannabinoid CB1 receptor in adolescent and adult binge drinking. Binge consumption was established in adolescent and adult male C57BL/6J mice by providing access to 20% alcohol or 1% sucrose for 4 h every other day. Pretreatment with the CB1 antagonist/inverse agonist AM-251 (0, 1, 3, and 10 mg/kg) in a Latin square design dose-dependently reduced adolescent alcohol consumption to adult levels without altering adult intake. AM-251 (3 mg/kg) also reduced adolescent but not adult sucrose consumption. Adolescent reductions in alcohol and sucrose were not associated with alterations in open-field locomotor activity or thigmotaxis. These findings point to age differences in CB1 receptor activity as a functional mediator of adolescent-typical increased binge drinking as compared to adults. Developmental alterations in endocannabinoid signaling in the adolescent brain may therefore be responsible for the drinking phenotype seen in this age group. PMID:26800788

  4. 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

  5. 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

  6. Sustained wash-resistant receptor activation responses of GPR119 agonists.

    Science.gov (United States)

    Hothersall, J Daniel; Bussey, Charlotte E; Brown, Alastair J; Scott, James S; Dale, Ian; Rawlins, Philip

    2015-09-01

    G protein-coupled receptor 119 (GPR119) is involved in regulating metabolic homoeostasis, with GPR119 agonists targeted for the treatment of type-2 diabetes and obesity. Using the endogenous agonist oleoylethanolamide and a number of small molecule synthetic agonists we have investigated the temporal dynamics of receptor signalling. Using both a dynamic luminescence biosensor-based assay and an endpoint cAMP accumulation assay we show that agonist-driven desensitization is not a major regulatory mechanism for GPR119 despite robust activation responses, regardless of the agonist used. Temporal analysis of the cAMP responses demonstrated sustained signalling resistant to washout for some, but not all of the agonists tested. Further analysis indicated that the sustained effects of one synthetic agonist AR-231,453 were consistent with a role for slow dissociation kinetics. In contrast, the sustained responses to MBX-2982 and AZ1 appeared to involve membrane deposition. We also detect wash-resistant responses to AR-231,453 at the level of physiologically relevant responses in an endogenous expression system (GLP-1 secretion in GLUTag cells). In conclusion, our findings indicate that in a recombinant expression system GPR119 activation is sustained, with little evidence of pronounced receptor desensitization, and for some ligands persistent agonist responses continue despite removal of excess agonist. This provides novel understanding of the temporal responses profiles of potential drug candidates targetting GPR119, and highlights the importance of carefully examining the the mechanisms through which GPCRs generate sustained responses. PMID:26101059

  7. 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.)

  8. 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

  9. Interactions of dopamine agonists with brain D1 receptors labeled by 3H-antagonists. Evidence for the presence of high and low affinity agonist-binding states

    International Nuclear Information System (INIS)

    The interactions of dopaminergic agonists and antagonists with 3H-antagonist labeled D1 dopamine receptors of rat striatum have been characterized. [3H]Flupentixol has been found to selectively label D1 dopamine receptors when its binding to D2 dopamine receptors is blocked by the inclusion of D2 selective concentrations of unlabeled spiroperidol or domperidone. Antagonist/3H-antagonist competition curves are of uniformly steep slope (nH . 1.0) suggesting the presence of a single D1 dopamine receptor. Agonist/3H-antagonist competition curves are extremely shallow (nH less than or equal to 0.5) for agonists of high relative efficacy, suggesting the presence of heterogeneous populations of agonist-binding states of the D1 dopamine receptor. Computer-modeling techniques were used to estimate affinities and relative site densities for these heterogeneous binding states. This analysis indicates that the ratio of agonist affinities for low and high affinity agonist-binding states is correlated with agonist relative efficacies in activating adenylate cyclase in membrane homogenates. Under the assay conditions employed, the addition of saturating concentrations of guanine nucleotides reduced, but did not abolish, the relative density of high affinity agonist-binding sites. These binding data can, at least in part, be explained by postulating two states of the D1 dopamine receptor, inducible by agonists but not by antagonists and modulated by guanine nucleotides

  10. Cardiovascular Effects of Glucagon-Like Peptide-1 Receptor Agonists.

    Science.gov (United States)

    Kang, Yu Mi; Jung, Chang Hee

    2016-06-01

    Glucagon-like peptide-1 (GLP-1) is a member of the proglucagon incretin family, and GLP-1 receptor agonists (RAs) have been introduced as a new class of antidiabetic medications in the past decade. The benefits of GLP-1 RAs are derived from their pleiotropic effects, which include glucose-dependent insulin secretion, suppressed glucagon secretion, and reduced appetite. Moreover, GLP-1 RAs also exert beneficial roles on multiple organ systems in which the GLP-1 receptors exist, including the cardiovascular system. Cardiovascular effects of GLP-1 RAs have been of great interest since the burden from cardiovascular diseases (CVD) has been unbearably increasing in a diabetic population worldwide, despite strict glycemic control and advanced therapeutic techniques to treat CVD. Preclinical studies have already demonstrated the beneficial effects of GLP-1 on myocardium and vascular endothelium, and many clinical studies evaluating changes in surrogate markers of CVD have suggested potential benefits from the use of GLP-1 RAs. Data from numerous clinical trials primarily evaluating the antihyperglycemic effects of multiple GLP-1 RAs have also revealed that changes in most CVD risk markers reported as secondary outcomes have been in favor of GLP-1 RAs treatment. However, to date, there is only one randomized clinical trial of GLP-1 RAs (the ELIXA study) evaluating major cardiovascular events as their primary outcomes, and in this study, a neutral cardiovascular effect of lixisenatide was observed in high-risk diabetic subjects. Therefore, the results of ongoing CVD outcome trials with the use of GLP-1 RAs should be awaited to elucidate the translation of benefits previously seen in CVD risk marker studies into large clinical trials with primary cardiovascular outcomes. PMID:27118277

  11. 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

  12. 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.

  13. Association Study of Two Cannabinoid Receptor Genes, CNR1 and CNR2, with Methamphetamine Dependence

    Science.gov (United States)

    Okahisa, Y; Kodama, M; Takaki, M; Inada, T; Uchimura, N; Yamada, M; Iwata, N; Iyo, M; Sora, I; Ozaki, N; Ujike, H

    2011-01-01

    Several studies have suggested that the endocannabinoid system plays significant roles in the vulnerability to psychiatric disorders including drug abuse. To examine the possible association of the CNR1 and CNR2 genes, which encode cannabinoid receptors CB1 and CB2, with methamphetamine dependence, we investigated three single nucleotide polymorphisms (SNPs) (rs806379, rs1535255, rs2023239) in intron 2 of the CNR1 gene and a nonsynonymous SNP, Q63R, in the CNR2 gene. The study samples consisted of 223 patients with methamphetamine dependence and 292 age- and sex- matched controls. There were no significant differences between the patients and controls in genotypic or allelic distribution of any SNP of the CNR1 and CNR2 genes. We also analyzed the clinical features of methamphetamine dependence. Rs806379 of the CNR1 gene showed a significant association with the phenotype of latency of psychosis after the first consumption of methamphetamine. Patients with the T allele or T-positive genotypes (T/T or A/T) may develop a rapid onset of psychosis after methamphetamine abuse. The present study suggests a possibility that genetic variants of the CNR1 gene may produce a liability to the complication of psychotic state after abuse of methamphetamine; however, our findings need to be confirmed by future replications. PMID:21886587

  14. Preclinical evaluation of [11C]NE40, a type 2 cannabinoid receptor PET tracer

    International Nuclear Information System (INIS)

    Introduction: Up-regulation of the type 2 cannabinoid receptor (CB2R) has been reported in (neuro)inflammatory diseases. In this study, we report the preclinical evaluation of [11C]NE40 as positron emission tomography (PET) radioligand for visualization of the CB2R. Methods: The selectivity of NE40 for CB2R and its toxicity and mutagenicity were determined. [11C]NE40 was evaluated by biodistribution and autoradiography studies in normal rats and a microPET study in normal mice, rats and a rhesus monkey. Specific in vivo binding of [11C]NE40 to human CB2R (hCB2R) was studied in a rat model with hCB2R overexpression. Results: [11C]NE40 shows specific CB2R binding in the spleen and blood of normal rats and high brain uptake in rhesus monkey. [11C]NE40 showed specific and reversible binding to hCB2R in vivo in a rat model with local hCB2R overexpression. Conclusions: [11C]NE40 shows favorable characteristics as radioligand for in vivo visualization of the CB2R and is a promising candidate for hCB2R PET imaging.

  15. Effects of deleting cannabinoid receptor-2 on mechanical and material properties of cortical and trabecular bone

    Directory of Open Access Journals (Sweden)

    Aysha B. Khalid

    2015-12-01

    Full Text Available Cnr2 is one of two cannabinoid receptors known to regulate bone metabolism. Here, we compared the whole bone properties of femora and tibiae from three-month-old Cnr2−/- mice with wild-type controls using a C57BL/6 background. Bending stiffness was measured by three-point bending. The elastic modulus, density and mineral content were measured using ultrasound, Archimedes’ principle and ashing. Micro-CT was used to measure the second moment of area, inner and outer perimeters of the cortical shaft and trabecular parameters. Deleting Cnr2 increased the bending stiffness by increasing the second moment of area. Bone from affected male mice had a greater modulus than controls, although no difference was observed in females. The fractional volume of trabecular bone was greater in Cnr2−/- females than controls, while no difference was seen in males. These data indicate that inactivating Cnr2 increases the amount of cortical bone in both males and females at 3 months of age, but the effect on trabecular bone is different in the two sexes. These findings extend previous studies looking only at trabecular bone and provide further support for the possible use of Cnr2 antagonists for improving bone properties that may be of value in the treatment of bone disorders.

  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; Kiselyov, Vladislav V; Berezin, Vladimir; Bock, Elisabeth

    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...

  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. Positive cooperativity of acetylcholine and other agonists with allosteric ligands on muscarinic acetylcholine receptors.

    Science.gov (United States)

    Jakubík, J; Bacáková, L; El-Fakahany, E E; Tucek, S

    1997-07-01

    It is well known that allosteric modulators of muscarinic acetylcholine receptors can both diminish and increase the affinity of receptors for their antagonists. We investigated whether the allosteric modulators can also increase the affinity of receptors for their agonists. Twelve agonists and five allosteric modulators were tested in experiments on membranes of CHO cells that had been stably transfected with genes for the M1-M4 receptor subtypes. Allosterically induced changes in the affinities for agonists were computed from changes in the ability of a fixed concentration of each agonist to compete with [3H]N-methylscopolamine for the binding to the receptors in the absence and the presence of varying concentrations of allosteric modulators. The effects of allosteric modulators varied greatly depending on the agonists and the subtypes of receptors. The affinity for acetylcholine was augmented by (-)-eburnamonine on the M2 and M4 receptors and by brucine on the M1 and M3 receptors. Brucine also enhanced the affinities for carbachol, bethanechol, furmethide, methylfurmethide, pilocarpine, 3-(3-pentylthio-1,2,5-thiadiazol-4-yl)-1,2,5,6-tetrahydro-1- methylpyridine (pentylthio-TZTP), oxotremorine-M, and McN-A-343 on the M1, M3, and M4 receptors, for pentylthio-TZTP on the M2 receptors, and for arecoline on the M3 receptors. (-)-Eburnamonine enhanced the affinities for carbachol, bethanechol, furmethide, methylfurmethide, pentylthio-TZTP, pilocarpine, oxotremorine and oxotremorine-M on the M2 receptors and for pilocarpine on the M4 receptors. Vincamine, strychnine, and alcuronium displayed fewer positive allosteric interactions with the agonists, but each allosteric modulator displayed positive cooperativity with at least one agonist on at least one muscarinic receptor subtype. The highest degrees of positive cooperativity were observed between (-)-eburnamonine and pilocarpine and (-)-eburnamonine and oxotremorine-M on the M2 receptors (25- and 7-fold increases in

  19. 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

  20. Mapping Cannabinoid 1 Receptor Allosteric Site(s): Critical Molecular Determinant and Signaling Profile of GAT100, a Novel, Potent, and Irreversibly Binding Probe.

    Science.gov (United States)

    Laprairie, Robert B; Kulkarni, Abhijit R; Kulkarni, Pushkar M; Hurst, Dow P; Lynch, Diane; Reggio, Patricia H; Janero, David R; Pertwee, Roger G; Stevenson, Lesley A; Kelly, Melanie E M; Denovan-Wright, Eileen M; Thakur, Ganesh A

    2016-06-15

    One of the most abundant G-protein coupled receptors (GPCRs) in brain, the cannabinoid 1 receptor (CB1R), is a tractable therapeutic target for treating diverse psychobehavioral and somatic disorders. Adverse on-target effects associated with small-molecule CB1R orthosteric agonists and inverse agonists/antagonists have plagued their translational potential. Allosteric CB1R modulators offer a potentially safer modality through which CB1R signaling may be directed for therapeutic benefit. Rational design of candidate, druglike CB1R allosteric modulators requires greater understanding of the architecture of the CB1R allosteric endodomain(s) and the capacity of CB1R allosteric ligands to tune the receptor's information output. We have recently reported the synthesis of a focused library of rationally designed, covalent analogues of Org27569 and PSNCBAM-1, two prototypic CB1R negative allosteric modulators (NAMs). Among the novel, pharmacologically active CB1R NAMs reported, the isothiocyanate GAT100 emerged as the lead by virtue of its exceptional potency in the [(35)S]GTPγS and β-arrestin signaling assays and its ability to label CB1R as a covalent allosteric probe with significantly reduced inverse agonism in the [(35)S]GTPγS assay as compared to Org27569. We report here a comprehensive functional profiling of GAT100 across an array of important downstream cell-signaling pathways and analysis of its potential orthosteric probe-dependence and signaling bias. The results demonstrate that GAT100 is a NAM of the orthosteric CB1R agonist CP55,940 and the endocannabinoids 2-arachidonoylglycerol and anandamide for β-arrestin1 recruitment, PLCβ3 and ERK1/2 phosphorylation, cAMP accumulation, and CB1R internalization in HEK293A cells overexpressing CB1R and in Neuro2a and STHdh(Q7/Q7) cells endogenously expressing CB1R. Distinctively, GAT100 was a more potent and efficacious CB1R NAM than Org27569 and PSNCBAM-1 in all signaling assays and did not exhibit the inverse

  1. 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

  2. Opposite function of dopamine D1 and NMDA receptors in striatal cannabinoid-mediated signaling

    OpenAIRE

    Daigle, Tanya L.; Wetsel, William C.; Caron, Marc G.

    2011-01-01

    It is well established that the cannabinoid and dopamine systems interact at various levels to regulate basal ganglia function. While it is well known that acute administration of cannabinoids to mice can modify dopamine-dependent behaviors, an understanding of the intraneuronal signaling pathways employed by these agents in the striatum is not well understood. Here we use knockout (KO) mouse models to examine the regulation of striatal ERK1/2 signaling by behaviorally relevant doses of canna...

  3. 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

  4. 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

  5. Cannabinoid receptor activation prevents the effects of chronic mild stress on emotional learning and LTP in a rat model of depression.

    Science.gov (United States)

    Segev, Amir; Rubin, Adva S; Abush, Hila; Richter-Levin, Gal; Akirav, Irit

    2014-03-01

    Most psychiatric disorders are characterized by emotional memory or learning disturbances. Chronic mild stress (CMS) is a common animal model for stress-induced depression. Here we examined whether 3 days of treatment using the CB1/2 receptor agonist WIN55,212-2 could ameliorate the effects of CMS on emotional learning (ie, conditioned avoidance and extinction), long-term potentiation (LTP) in the hippocampal-accumbens pathway, and depression-like symptoms (ie, coping with stress behavior, anhedonia, and weight changes). We also examined whether the ameliorating effects of WIN55,212-2 on behavior and physiology after CMS are mediated by CB1 and glucocorticoid receptors (GRs). Rats were exposed to CMS or handled on days 1-21. The agonist WIN55,212-2 or vehicle were administered on days 19-21 (IP; 0.5 mg/kg) and behavioral and electrophysiological measures were taken on days 23 and 28. The CB1 receptor antagonist AM251 (IP; 0.3 mg/kg) or the GR antagonist RU-38486 (IP; 10 mg/kg) were co-administered with WIN55,212-2. Our results show that CMS significantly modified physiological and behavioral reactions, as observed by the impairment in avoidance extinction and LTP in the hippocampal-accumbens pathway, and the alterations in depression-like symptoms, such as coping with stress behavior, weight gain, and sucrose consumption. The most significant effect observed in this study was that 3 days of WIN55,212-2 administration prevented the CMS-induced alterations in emotional memory (ie, extinction) and plasticity. This effect was mediated by CB1 receptors as the CB1 receptor antagonist AM251 prevented the ameliorating effects of WIN55,212-2 on extinction and LTP. The GR antagonist RU-38486 also prevented the CMS-induced alterations in extinction and plasticity, and when co-administered with WIN55,212-2, the preventive effects after CMS were maintained. The findings suggest that enhancing cannabinoid signaling could represent a novel approach to the treatment of cognitive

  6. 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

  7. 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

  8. 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

  9. 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)

  10. 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).

  11. 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

    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 beta(2)-adrenergic receptor,...

  12. 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

  13. Structure-guided development of dual β2 adrenergic/dopamine D2 receptor agonists.

    Science.gov (United States)

    Weichert, Dietmar; Stanek, Markus; Hübner, Harald; Gmeiner, Peter

    2016-06-15

    Aiming to discover dual-acting β2 adrenergic/dopamine D2 receptor ligands, a structure-guided approach for the evolution of GPCR agonists that address multiple targets was elaborated. Starting from GPCR crystal structures, we describe the design, synthesis and biological investigation of a defined set of compounds leading to the identification of the benzoxazinone (R)-3, which shows agonist properties at the adrenergic β2 receptor and substantial G protein-promoted activation at the D2 receptor. This directed approach yielded molecular probes with tuned dual activity. The congener desOH-3 devoid of the benzylic hydroxyl function was shown to be a β2 adrenergic antagonist/D2 receptor agonist with Ki values in the low nanomolar range. The compounds may serve as a promising starting point for the investigation and treatment of neurological disorders. PMID:27132867

  14. The Roles of Opioid Receptors and agonists in health and disease Conditions

    Directory of Open Access Journals (Sweden)

    A.O. Ibegbu

    Full Text Available Opioid receptors are found in the central nervous system (CNS and are classified as mu (µ, kappa (κ, delta (δ and sigma (σ opioid receptors. Opioid receptors belong to the large family of G protein coupled receptors (GPCRs, and have diverse and important physiological roles. Opioid receptors are not uniformly distributed in the CNS and are found in areas concerned with pain, with the highest concentration in the cerebral cortex, followed by the amygdala, septum, thalamus, hypothalamus, midbrain and spinal cord. Activated delta opioid receptors are coupled to Gi1 while activated mu opioid receptors are coupled to Gi3 in neuroblastoma cells. Mu opioid receptors are activated by mu receptor agonists and are coupled through the Gαi1 and GαoA. Both mu and kappa opioid receptors are coupled via both Gi and Gz and opioid receptors are important targets for thousands of pharmacological agents. GPCRs typically require activation by agonists for their signalling activity to be initiated but some of the GPCRs may display basal or spontaneous signalling activity in the absence of an agonist. The stimulation of these receptors triggers analgesic effects and affects the function of the nervous system, gastrointestinal tract and other body systems. Hundreds of analogs of opioid peptides have been synthesized in an effort to make the compounds more active, selective, and resistant to biodegradation than the endogenous ligands. All these modifications resulted in obtaining very selective agonists and antagonists with high affinity at mu-, delta-, and kappa-opioid receptors, which are useful in further studies on the pharmacology of opioid receptors in a mammalian organism.

  15. 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...

  16. 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...

  17. 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.

  18. 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.

  19. Candidate PET radioligands for cannabinoid CB1 receptors: [18F]AM5144 and related pyrazole compounds

    International Nuclear Information System (INIS)

    Introduction: The mammalian brain contains abundant G protein-coupled cannabinoid CB1 receptors that respond to Δ9-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 CB1 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-[18F]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-[18F]fluoroaniline. The labeled precursor was synthesized from 1-[18F]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/μmol 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 CB1 receptors, absolute uptake at 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 CB1 receptor that may require very lipophilic ligands

  20. 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

  1. 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

  2. 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.

  3. 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...

  4. Serotonin(4) (5-HT(4)) receptor agonists are putative antidepressants with a rapid onset of action

    DEFF Research Database (Denmark)

    Lucas, Guillaume; Rymar, Vladimir V; Du, Jenny;

    2007-01-01

    Current antidepressants are clinically effective only after several weeks of administration. Here, we show that serotonin(4) (5-HT(4)) agonists reduce immobility in the forced swimming test, displaying an antidepressant potential. Moreover, a 3 day regimen with such compounds modifies rat brain p...... intake consecutive to a chronic mild stress. These findings point out 5-HT(4) receptor agonists as a putative class of antidepressants with a rapid onset of action. Udgivelsesdato: 2007-Sep-6...

  5. 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,...

  6. Triphasic blood pressure responses to cannabinoids: do we understand the mechanism?

    Science.gov (United States)

    Malinowska, Barbara; Baranowska-Kuczko, Marta; Schlicker, Eberhard

    2012-04-01

    The cannabinoids comprise three major classes of substances, including compounds derived from the cannabis plant (e.g. Δ(9) -tetrahydrocannabinol and the chemically related substances CP55940 and HU210), endogenously formed (e.g. anandamide) and synthetic compounds (e.g. WIN55212-2). Beyond their psychotropic effects, cannabinoids have complex effects on blood pressure, including biphasic changes of Δ(9) -tetrahydrocannabinol and WIN55212-2 and an even triphasic effect of anandamide. The differing pattern of blood pressure changes displayed by the three types of compounds is not really surprising since, although they share an agonistic effect at cannabinoid CB(1) and CB(2) receptors, some compounds have additional effects. In particular, anandamide is known for its pleiotropic effects, and there is overwhelming evidence that anandamide influences blood pressure via (i) CB(1) receptors, (ii) TRPV1 receptors, (iii) endothelial cannabinoid receptors and (iv) degradation products. This review is dedicated to the description of the effects of externally added cannabinoids on cardiovascular parameters in vivo. First, the cardiovascular effects of cannabinoids in anaesthetized animals will be highlighted since most data have been generated in experiments of that type. The text will follow the three phases of anandamide on blood pressure, and we will check to which extent cardiovascular changes elicited by other cannabinoids show overlap with those effects or differ. The second part will be dedicated to the cardiovascular effects of the cannabinoids in conscious animals. In the third part, cardiovascular effects in humans will be discussed, and similarities and differences with respect to the data from animals will be examined. PMID:22022923

  7. 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

  8. 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.

  9. 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

  10. Opposite control of frontocortical 2-arachidonoylglycerol turnover rate by cannabinoid type-1 receptors located on glutamatergic neurons and on astrocytes.

    Science.gov (United States)

    Belluomo, Ilaria; Matias, Isabelle; Pernègre, Camille; Marsicano, Giovanni; Chaouloff, Francis

    2015-04-01

    This study examined the respective influences of cannabinoid type-1 (CB1) receptors expressed either in forebrain GABAergic neurons, in cortical glutamatergic neurons, or in astrocytes on the turnover rates of the endocannabinoids N-arachidonoylethanolamide (AEA) and 2-arachidonoylglycerol (2-AG), and the non-cannabinoid N-acylethanolamides, palmitoylethanolamide (PEA), and oleoylethanolamide (OEA), in mouse forebrain regions. To this end, conditional mutant mice lacking CB1 receptors from either of these cell types were pre-treated systemically with JZL195, a dual inhibitor of fatty acid amide hydrolase, the enzyme degrading AEA, PEA, and OEA, and of monoacylglycerol lipase, the main 2-AG-degrading enzyme. The analyses of frontocortical, hippocampal, and striatal AEA, 2-AG, PEA, and OEA concentrations revealed that their respective baseline concentrations were not influenced by the mouse genotype. On the other hand, the accumulation of frontocortical and/or hippocampal 2-AG levels in JZL195-pre-treated mice was dependent on the mouse genotype. Thus, JZL195-induced 2-AG accumulation rates were diminished in the frontal cortex of mice lacking CB1 receptors in glutamatergic neurons while their respective values were increased in the frontal cortex and hippocampus of mice lacking these receptors in astrocytes. These genotypic differences occurred with parallel and proportionate changes in the fractional rate constants for degradation of 2-AG, thus providing a mechanism whereby the baseline levels of 2-AG remained constant between genotypes. Besides suggesting a cell-type-specific control of frontocortical and/or hippocampal 2-AG synthesis and degradation rates by CB1 receptors, this study highlights the interest of assessing endocannabinoid turnover rates when questioning the status of the endocannabinoid system. PMID:25626460

  11. 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 metabolic...

  12. 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.

  13. 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

  14. 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.

  15. 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

  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. 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.

  18. 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...

  19. 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.

  20. Structural Requirements of N-Substituted Spiropiperidine Analogues as Agonists of Nociceptin/Orphanin FQ Receptor

    Directory of Open Access Journals (Sweden)

    Ling Yang

    2011-12-01

    Full Text Available The nociceptin/orphanin FQ (NOP receptor is involved in a wide range of biological functions, including pain, anxiety, depression and drug abuse. Especially, its agonists have great potential to be developed into anxiolytics. In this work, both the ligand- and receptor-based three-dimensional quantitative structure–activity relationship (3D-QSAR studies were carried out using comparative molecular field analysis (CoMFA and comparative molecular similarity indices analysis (CoMSIA techniques on 103 N-substituted spiropiperidine analogues as NOP agonists. The resultant optimal ligand-based CoMSIA model exhibited Q2 of 0.501, R2ncv of 0.912 and its predictive ability was validated by using an independent test set of 26 compounds which gave R2pred value of 0.818. In addition, docking analysis and molecular dynamics simulation (MD were also applied to elucidate the probable binding modes of these agonists. Interpretation of the 3D contour maps, in the context of the topology of the active site of NOP, provided insight into the NOP-agonist interactions. The information obtained from this work can be used to accurately predict the binding affinity of related agonists and also facilitate the future rational design of novel agonists with improved activity.

  1. 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

  2. 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

  3. Cannabinoids alter spontaneous firing, bursting and cell synchrony of hippocampal principal cells

    OpenAIRE

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

    2011-01-01

    Both natural and synthetic cannabinoid receptor (e.g. CB1) agonists such as Δ9-THC, WIN 55,212-2 (WIN-2) and HU-210 disrupt spatial cognition presumably through the inhibition of synchrony of hippocampal ensemble firing to task-related events (Hampson and Deadwyler, J. of Neuroscience, 2000; 20:8932-8942; Robinson et al., Brit. J. Pharmacology, 2007; 151:688-700). And although the CB1 receptor agonist CP 55,940 also disrupts the synchronous firing of hippocampal neurons, it does not seem to a...

  4. 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.

  5. 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

  6. 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.

  7. 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 ...

  8. 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 ...

  9. 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...

  10. 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. PMID:26476280

  11. Cannabinoid receptors are involved in the protective effect of a novel curcumin derivative C66 against CCl4-induced liver fibrosis.

    Science.gov (United States)

    Huang, Si-Si; Chen, Da-Zhi; Wu, He; Chen, Rui-Cong; Du, Shan-Jie; Dong, Jia-Jia; Liang, Guang; Xu, Lan-Man; Wang, Xiao-Dong; Yang, Yong-Ping; Yu, Zhen-Ping; Feng, Wen-Ke; Chen, Yong-Ping

    2016-05-15

    Liver fibrosis is one of the major causes of morbidity and mortality worldwide and lacks efficient therapy. Recent studies suggest the curcumin protects liver from fibrosis. However, curcumin itself is in low bioavailable concentration when administered orally, and the protective mechanism remains poorly understood. The current study aimed to investigate whether a more stable derivative of curcumin, C66, protects against CCl4-inudced liver fibrosis and examine the underlying mechanism involving cannabinoid receptor (CB receptor). At a dose lower than curcumin itself, C66 displayed a superior anti-fibrotic effect. C66 significantly reduced collagen deposition, pro-inflammatory cytokine expression, and liver enzyme activities. Mechanistic study revealed that C66 treatment decreased CCl4-induced cannabinoid receptor 1 (CB1 receptor) expression and increased cannabinoid receptor 2 (CB2 receptor) expression, along with an inhibition of JNK/NF-κB-mediated inflammatory signaling. In conclusion, this curcumin derivative attenuates liver fibrosis likely involving a CB/JNK/NF-κB-mediated pathway. PMID:26945822

  12. 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

    and MOR. A short SAR exploration with the objective of identifying more polar and hence less brain penetrant agonists is described herewith. Modeling studies of the recently published structures of KOR, DOR and MOR are used to explain the receptor selectivity. The synthesis, biological evaluation and SAR...

  13. Contradictory effects of GABA-B receptor agonists on cortical epileptic afterdischarges in immature rats

    Czech Academy of Sciences Publication Activity Database

    Mareš, Pavel; Tabashidze, Nana

    2008-01-01

    Roč. 75, č. 1 (2008), s. 173-178. ISSN 0361-9230 R&D Projects: GA ČR(CZ) GA305/05/2581 Institutional research plan: CEZ:AV0Z50110509 Keywords : GABA -B receptor agonists * epileptic afterdischarges * cortex Subject RIV: FH - Neurology Impact factor: 2.281, year: 2008

  14. Effect of GABAB receptor agonist SKF97541 on cortical and hippocampal epileptic afterdischarges

    Czech Academy of Sciences Publication Activity Database

    Fábera, Petr; Mareš, Pavel

    2014-01-01

    Roč. 63, č. 4 (2014), s. 529-534. ISSN 0862-8408 R&D Projects: GA ČR(CZ) GBP304/12/G069; GA ČR(CZ) GAP304/10/1274 Institutional support: RVO:67985823 Keywords : GABAB receptor * agonist * hippocampus * cortex * epileptic afterdischarges * rat Subject RIV: FH - Neurology Impact factor: 1.293, year: 2014

  15. 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...

  16. 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

  17. 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...

  18. 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...

  19. 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.

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

    Czech Academy of Sciences Publication Activity Database

    Jakubík, Jan; Janíčková, Helena; El-Fakahany, E. E.; Doležal, Vladimír

    2011-01-01

    Roč. 162, č. 5 (2011), s. 1029-1044. ISSN 0007-1188 R&D Projects: GA ČR(CZ) GA305/09/0681; GA AV ČR(CZ) IAA500110703; GA MŠk(CZ) LC554 Institutional research plan: CEZ:AV0Z50110509 Keywords : acetylcholine * muscarinic receptor * GDP Subject RIV: FH - Neurology Impact factor: 4.409, year: 2011

  1. Feeding induced by cannabinoids is mediated independently of the melanocortin system.

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    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.

  2. Cannabinoid-Induced Hyperemesis: A Conundrum—From Clinical Recognition to Basic Science Mechanisms

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    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.

  3. 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...

  4. 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

  5. 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...

  6. 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.

  7. Inhibitory effects of sigma-2 receptor agonists on T lymphocyte activation

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    MANUELFRESNO

    2013-03-01

    Full Text Available Sigma (σ receptor ligands are essentially known for their effects on the nervous system although recent studies have shown their potential effects modulating some other pathophysiological processes as cell proliferation, cancer and the immune response. Here, we have analyzed the actions of σ-1 and σ-2 receptors ligands on T cell activation. Our results show that treatment of Jurkat T cells with σ-2 agonists decreased the induction of the expression of Interleukin (IL-2, Tumor necrosis factor (TNF-α and Cyclooxygenase (COX-2 by activated T cells in a dose–dependent manner. These effects take place at the transcriptional level since σ-2 agonists BD-737 and CB-184 diminished the activity of the promoters of those genes. Those immunosuppressive effects could be attributable to interference with transcription factor activation. Induced transcription mediated by Nuclear factor (NF-κB or Nuclear Factor of Activated T cells (NFAT was inhibited by σ-2 agonists. These effects seem to be specific for σ-2 agonists as no significant effects on T cell activation by σ-1 ligands PRE-084 and BD-1063 were found. Our results provide new insights into the immunomodulatory actions of σ ligands and describe a new property of σ-2 agonists, through inhibition of activation of transcription factors as NFAT by which these compounds are regulating gene expression. This may have important consequences on the possible therapeutic use of those compounds.

  8. 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

  9. 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

  10. 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

  11. 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

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    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.

  12. 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

  13. 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.

  14. Guanine nucleotide regulation of dopamine receptor agonist affinity states in rat estradiol-induced pituitary tumors

    International Nuclear Information System (INIS)

    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 3H]-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'-[β-γ-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

  15. Synthesis and enantiopharmacology of new AMPA-kainate receptor agonists

    DEFF Research Database (Denmark)

    Conti, P; De Amici, M; De Sarro, G;

    1999-01-01

    Regioisomeric 3-carboxyisoxazolinyl prolines [CIP-A (+/-)-6 and CIP-B (+/-)-7] and 3-hydroxyisoxazolinyl prolines [(+/-)-8 and (+/-)-9] were synthesized and assayed for glutamate receptor activity. The tests were carried out in vitro by means of receptor binding techniques, second messenger assays......, 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...... in mice at doses as low as 3.2 nmol/mouse. On the basis of the above-reported results we prepared and tested the enantiomers of CIP-A and CIP-B, obtained by reacting (S)-3,4-didehydroproline and (R)-3,4-didehydroproline, respectively, with ethoxycarbonylformonitrile oxide. In all the tests the S...

  16. 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)

  17. 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

  18. 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...

  19. 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...

  20. A novel control of human keratin expression: cannabinoid receptor 1-mediated signaling down-regulates the expression of keratins K6 and K16 in human keratinocytes in vitro and in situ

    Directory of Open Access Journals (Sweden)

    Yuval Ramot

    2013-02-01

    Full Text Available Cannabinoid receptors (CB are expressed throughout human skin epithelium. CB1 activation inhibits human hair growth and decreases proliferation of epidermal keratinocytes. Since psoriasis is a chronic hyperproliferative, inflammatory skin disease, it is conceivable that the therapeutic modulation of CB signaling, which can inhibit both proliferation and inflammation, could win a place in future psoriasis management. Given that psoriasis is characterized by up-regulation of keratins K6 and K16, we have investigated whether CB1 stimulation modulates their expression in human epidermis. Treatment of organ-cultured human skin with the CB1-specific agonist, arachidonoyl-chloro-ethanolamide (ACEA, decreased K6 and K16 staining intensity in situ. At the gene and protein levels, ACEA also decreased K6 expression of cultured HaCaT keratinocytes, which show some similarities to psoriatic keratinocytes. These effects were partly antagonized by the CB1-specific antagonist, AM251. While CB1-mediated signaling also significantly inhibited human epidermal keratinocyte proliferation in situ, as shown by K6/Ki-67-double immunofluorescence, the inhibitory effect of ACEA on K6 expression in situ was independent of its anti-proliferative effect. Given recent appreciation of the role of K6 as a functionally important protein that regulates epithelial wound healing in mice, it is conceivable that the novel CB1-mediated regulation of keratin 6/16 revealed here also is relevant to wound healing. Taken together, our results suggest that cannabinoids and their receptors constitute a novel, clinically relevant control element of human K6 and K16 expression.

  1. Agouti signalling protein is an inverse agonist to the wildtype and agonist to the melanic variant of the melanocortin-1 receptor in the grey squirrel (Sciurus carolinensis).

    Science.gov (United States)

    McRobie, Helen R; King, Linda M; Fanutti, Cristina; Symmons, Martyn F; Coussons, Peter J

    2014-06-27

    The melanocortin-1 receptor (MC1R) is a key regulator of mammalian pigmentation. Melanism in the grey squirrel is associated with an eight amino acid deletion in the mutant melanocortin-1 receptor with 24 base pair deletion (MC1RΔ24) variant. We demonstrate that the MC1RΔ24 exhibits a higher basal activity than the wildtype MC1R (MC1R-wt). We demonstrate that agouti signalling protein (ASIP) is an inverse agonist to the MC1R-wt but is an agonist to the MC1RΔ24. We conclude that the deletion in the MC1RΔ24 leads to a receptor with a high basal activity which is further activated by ASIP. This is the first report of ASIP acting as an agonist to MC1R. PMID:24879893

  2. Time and space profiling of NMDA receptor co-agonist functions.

    Science.gov (United States)

    Mothet, Jean-Pierre; Le Bail, Matildé; Billard, Jean-Marie

    2015-10-01

    The N-Methyl D-Aspartic acid (NMDA) receptors (NMDAR) are key tetrameric ionotropic glutamate receptors that transduce glutamatergic signals throughout the central nervous system (CNS) and spinal cord. Although NMDARs are diverse in their subunit composition, subcellular localization, and biophysical and pharmacological properties, their activation always requires the binding of a co-agonist that has long been thought to be glycine. However, intense research over the last decade has challenged this classical model by showing that another amino acid, d-serine, is the preferential co-agonist for a subset of synaptic NMDARs in many areas of the adult brain. Nowadays, a totally new picture of glutamatergic synapses at work is emerging where both glycine and d-serine are involved in a complex interplay to regulate NMDAR functions in the CNS following time and space constraints. The purpose of this review was to highlight the particular role of each co-agonist in modulating NMDAR-dependent activities in healthy and diseased brains. We have herein integrated our most advanced knowledge of how glycine and d-serine may orchestrate synapse dynamics and drive neuronal network activity in a time- and synapse-specific manner and how changes in synaptic availability of these amino acids may contribute to cognitive impairments such as those associated with healthy aging, epilepsy, and schizophrenia. The N-Methyl D-Aspartic acid (NMDA) subtype of glutamate receptors are central to many physiological functions and are linked to brain disorders. Their functions require glutamate and a co-agonist d-serine or glycine. After years of intense research and controversy on the identity of the amino acid that serves as the right co-agonist, we are just entering a new era of consensus where glycine and d-serine are teaming up to regulate the function of different subsets of NMDA receptors and at different synapses during different time windows of brain development. PMID:26088787

  3. Dopexamine: a novel agonist at peripheral dopamine receptors and beta 2-adrenoceptors.

    OpenAIRE

    Brown, R. A.; Dixon, J; Farmer, J. B.; Hall, J.C.; Humphries, R. G.; Ince, F.; O'Connor, S. E.; Simpson, W T; Smith, G W

    1985-01-01

    Dopexamine is an agonist at peripheral dopamine receptors and at beta 2-adrenoceptors. Dopexamine has approximately one-third the potency of dopamine in stimulating the vascular DA1-receptor in the dog, resulting in a fall in renal vascular resistance of 20% at 2.3 X 10(-8) mol kg-1 (i.a.). Prejunctional DA2-receptors are also stimulated by dopexamine, resulting in a reduction of neurogenic vasoconstriction in the rabbit isolated ear artery (IC50 of 1.15 X 10(-6)M) and of neurogenic tachycard...

  4. Action of fenoldopam, a selective dopamine (DA1) receptor agonist, on isolated human arteries.

    Science.gov (United States)

    Hughes, A D; Sever, P S

    1989-01-01

    The effects of a DA1 dopamine receptor selective agonist, fenoldopam, were examined on human blood vessels. Fenoldopam relaxed precontracted human arteries in vitro from brachial, cerebral, cervical, colic, coronary, lumbar, pulmonary, renal and splenic sites. Fenoldopam failed to relax uterine or external iliac arteries or saphenous vein segments. These effects of fenoldopam were not endothelium dependent, but were antagonised by the selective DA1 receptor antagonists, SCH 23390, (+)-butaclamol, and (R)- more than (S)-sulpiride. The effect of fenoldopam may involve cyclic adenosine monophosphate. These studies indicate the presence of DA1 receptors on a variety of large isolated human arteries. PMID:2474340

  5. 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...

  6. 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.

  7. 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...

  8. Functional effects of the muscarinic receptor agonist, xanomeline, at 5-HT1 and 5-HT2 receptors

    OpenAIRE

    Watson, J.; Brough, S.; Coldwell, M C; Gager, T; Ho, M; Hunter, A. J.; Jerman, J; Middlemiss, D. N.; Riley, G J; Brown, A M

    1998-01-01

    Xanomeline [3(3-hexyloxy-1,2,5-thiadiazol-4-yl)-1,2,5,6-tetrahydro-1-methylpyridine] has been reported to act as a functionally selective muscarinic partial agonist with potential use in the treatment of Alzheimer's disease. This study examined the functional activity of xanomeline at 5-HT1 and 5-HT2 receptors in native tissue and/or human cloned receptors.Xanomeline had affinity for muscarinic receptors in rat cortical membranes where the ratio of the displacement affinity of [3H]-Quinuclidi...

  9. 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.

  10. 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.

  11. Enkephalin levels and the number of neuropeptide Y-containing interneurons in the hippocampus are decreased in female cannabinoid-receptor 1 knock-out mice.

    Science.gov (United States)

    Rogers, Sophie A; Kempen, Tracey A Van; Pickel, Virginia M; Milner, Teresa A

    2016-05-01

    Drug addiction requires learning and memory processes that are facilitated by activation of cannabinoid-1 (CB1) and opioid receptors in the hippocampus. This involves activity-dependent synaptic plasticity that is partially regulated by endogenous opioid (enkephalin and dynorphin) and non-opioid peptides, specifically cholecystokinin, parvalbumin and neuropeptide Y, the neuropeptides present in inhibitory interneurons that co-express CB1 or selective opioid receptors. We tested the hypothesis that CB1 receptor expression is a determinant of the availability of one or more of these peptide modulators in the hippocampus. This was achieved by quantitatively analyzing the immunoperoxidase labeling for each of these neuropeptide in the dorsal hippocampus of female wild-type (CB1+/+) and cannabinoid receptor 1 knockout (CB1-/-) C57/BL6 mice. The levels of Leu(5)-enkephalin-immunoreactivity were significantly reduced in the hilus of the dentate gyrus and in stratum lucidum of CA3 in CB1-/- mice. Moreover, the numbers of neuropeptide Y-immunoreactive interneurons in the dentate hilus were significantly lower in the CB1-/- compared to wild-type mice. However, CB1+/+ and CB1-/- mice did not significantly differ in expression levels of either dynorphin or cholecystokinin, and showed no differences in numbers of parvalbumin-containing interneurons. These findings suggest that the cannabinoid and opioid systems have a nuanced, regulatory relationship that could affect the balance of excitation and inhibition in the hippocampus and thus processes such as learning that rely on this balance. PMID:27012427

  12. 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

  13. Small-molecule nociceptin receptor agonist ameliorates mast cell activation and pain in sickle mice.

    Science.gov (United States)

    Vang, Derek; Paul, Jinny A; Nguyen, Julia; Tran, Huy; Vincent, Lucile; Yasuda, Dennis; Zaveri, Nurulain T; Gupta, Kalpna

    2015-12-01

    Treatment of pain with morphine and its congeners in sickle cell anemia is suboptimal, warranting the need for analgesics devoid of side effects, addiction and tolerance liability. Small-molecule nociceptin opioid receptor ligands show analgesic efficacy in acute and chronic pain models. We show that AT-200, a high affinity nociceptin opioid receptor agonist with low efficacy at the mu opioid receptor, ameliorated chronic and hypoxia/reoxygenation-induced mechanical, thermal and deep tissue/musculoskeletal hyperalgesia in HbSS-BERK sickle mice. The antinociceptive effect of AT-200 was antagonized by SB-612111, a nociceptin opioid receptor antagonist, but not naloxone, a non-selective mu opioid receptor antagonist. Daily 7-day treatment with AT-200 did not develop tolerance and showed a sustained anti-nociceptive effect, which improved over time and led to reduced plasma serum amyloid protein, neuropeptides, inflammatory cytokines and mast cell activation in the periphery. These data suggest that AT-200 ameliorates pain in sickle mice via the nociceptin opioid receptor by reducing inflammation and mast cell activation without causing tolerance. Thus, nociceptin opioid receptor agonists are promising drugs for treating pain in sickle cell anemia. PMID:26294734

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

    DEFF Research Database (Denmark)

    Harpsøe, Kasper; Ahring, Philip K; Christensen, Jeppe K; Jensen, Marianne L; Peters, Dan; Balle, Thomas

    2011-01-01

    the observation of two distinct agonist sensitivities. Using different expression ratios of mammalian a4 and ß2 subunits and concatenated constructs, we demonstrate that a biphasic response is an intrinsic functional property of the (a4)(3)(ß2)(2) receptor. In addition to two high-sensitivity sites at...... a4ß2 interfaces, the (a4)(3)(ß2)(2) receptor contains a third low-sensitivity agonist binding site in the a4a4 interface. Occupation of this site is required for full activation and is responsible for the widened dynamic response range of this receptor subtype. By site-directed mutagenesis, we show...... that three residues, which differ between the a4ß2 and a4a4 sites, control agonist sensitivity. The results presented here provide a basic insight into the function of pentameric ligand-gated ion channels, which enables modulation of the receptors with hitherto unseen precision; it becomes possible to...

  15. Melanocortin MC4 receptor agonists alleviate brain damage in abdominal compartment syndrome in the rat.

    Science.gov (United States)

    Liu, Dong; Zhang, Hong-Guang; Zhao, Zi-Ai; Chang, Ming-Tao; Li, Yang; Yu, Jian; Zhang, Ye; Zhang, Lian-Yang

    2015-02-01

    Intra-abdominal hypertension (IAH) is accompanied by high morbidity and mortality in surgical departments and ICUs. However, its specific pathophysiology is unclear. IAH not only leads to intra-abdominal tissue damage but also causes dysfunction in distal organs, such as the brain. In this study, we explore the protective effects of melanocortin 4 receptor agonists in IAH-induced brain injury. The IAH rat models were induced by hemorrhagic shock/resuscitation (with the mean arterial pressure (MAP) maintained at 30 mm Hg for 90 min followed by the reinfusion of the withdrawn blood with lactated Ringer's solution). Then, air was injected into the peritoneal cavity of the rats to maintain an intra-abdominal pressure of 20 mm Hg for 4 h. The effects of the melanocortin 4 receptor agonist RO27-3225 in alleviating the rats' IAH brain injuries were observed, which indicated that RO27-3225 could reduce brain edema, the expressions of the IL-1β and TNF-α inflammatory cytokines, the blood-brain barrier's permeability and the aquaporin4 (AQP4) and matrix metalloproteinase 9 (MMP9) levels. Moreover, the nicotinic acetylcholine receptor antagonist chlorisondamine and the selective melanocortin 4 receptor antagonist HS024 can negate the protective effects of the RO27-3225. The MC4R agonist can effectively reduce the intracerebral proinflammatory cytokine gene expression and alleviate the brain injury caused by blood-brain barrier damage following IAH. PMID:25616531

  16. Therapeutic Potential of 5-HT2C Receptor Agonists for Addictive Disorders.

    Science.gov (United States)

    Higgins, Guy A; Fletcher, Paul J

    2015-07-15

    The neurotransmitter 5-hydroxytryptamine (5-HT; serotonin) has long been associated with the control of a variety of motivated behaviors, including feeding. Much of the evidence linking 5-HT and feeding behavior was obtained from studies of the effects of the 5-HT releaser (dex)fenfluramine in laboratory animals and humans. Recently, the selective 5-HT2C receptor agonist lorcaserin received FDA approval for the treatment of obesity. This review examines evidence to support the use of selective 5-HT2C receptor agonists as treatments for conditions beyond obesity, including substance abuse (particularly nicotine, psychostimulant, and alcohol dependence), obsessive compulsive, and excessive gambling disorder. Following a brief survey of the early literature supporting a role for 5-HT in modulating food and drug reinforcement, we propose that intrinsic differences between SSRI and serotonin releasers may have underestimated the value of serotonin-based pharmacotherapeutics to treat clinical forms of addictive behavior beyond obesity. We then highlight the critical involvement of the 5-HT2C receptor in mediating the effect of (dex)fenfluramine on feeding and body weight gain and the evidence that 5-HT2C receptor agonists reduce measures of drug reward and impulsivity. A recent report of lorcaserin efficacy in a smoking cessation trial further strengthens the idea that 5-HT2C receptor agonists may have potential as a treatment for addiction. This review was prepared as a contribution to the proceedings of the 11th International Society for Serotonin Research Meeting held in Hermanus, South Africa, July 9-12, 2014. PMID:25870913

  17. 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

  18. 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

  19. 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

  20. 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

  1. 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...

  2. 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

  3. 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

  4. 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. PMID:26189725

  5. Tweaking agonist efficacy at N-methyl-D-aspartate receptors by site-directed mutagenesis

    DEFF Research Database (Denmark)

    Hansen, Kasper B; Clausen, Rasmus P; Bjerrum, Esben J; Bechmann, Christian; Greenwood, Jeremy R; Christensen, Caspar; Kristensen, Jesper L; Egebjerg, Jan; Bräuner-Osborne, Hans

    2005-01-01

    . Key residues were selected for mutation based on ligand-protein docking studies using a homology model of NR2B-S1S2 built from the X-ray structure of NR1-S1S2 in complex with glycine. Wild-type and mutant forms of NR2B were coexpressed with NR1 in Xenopus laevis oocytes and characterized by two......The structural basis for partial agonism at N-methyl-D-aspartate (NMDA) receptors is currently unresolved. We have characterized several partial agonists at the NR1/NR2B receptor and investigated the mechanisms underlying their reduced efficacy by introducing mutations in the glutamate binding site...... increased steric clashes between agonists and the residues forming the S1-S2 interface, the agonists clearly show decreased relative efficacy. Furthermore, we demonstrate that the mutation S690A affects both potency and efficacy in an agonist-specific manner. The results indicate that essential residues in...

  6. Further evidence for association between genetic variants in the cannabinoid receptor 1 (CNR1) gene and cocaine dependence: Confirmation in an independent sample and meta-analysis

    OpenAIRE

    Clarke, Toni-Kim; Bloch, Paul J.; Ambrose-Lanci, Lisa M; Doyle, Glenn A.; Ferraro, Thomas N.; BERRETTINI, WADE H.; Kampman, Kyle M.; Dackis, Charles A.; Pettinati, Helen M.; O’Brien, Charles P.; Oslin, David W.; Lohoff, Falk W.

    2011-01-01

    Genetic research on cocaine dependence may help clarify our understanding of the disorder as well as provide insights for effective treatment. Since endocannabinoid signaling and dopamine neurotransmission have been shown to be involved with drug reward, genes related to these systems are plausible candidates for susceptibility to cocaine dependence. The cannabinoid receptor 1 (CB1) protein regulates both the endocannabinoid and dopaminergic neurobiological systems, and polymorphisms in the c...

  7. 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

  8. Gamma-lactams--a novel scaffold for highly potent and selective alpha 7 nicotinic acetylcholine receptor agonists.

    Science.gov (United States)

    Enz, Albert; Feuerbach, Dominik; Frederiksen, Mathias U; Gentsch, Conrad; Hurth, Konstanze; Müller, Werner; Nozulak, Joachim; Roy, Bernard L

    2009-03-01

    A novel class of alpha7 nicotinic acetylcholine receptor (nAChR) agonists has been discovered through high-throughput screening. The cis gamma-lactam scaffold has been optimized to reveal highly potent and selective alpha7 nAChR agonists with in vitro activity and selectivity and with good brain penetration in mice. PMID:19208472

  9. 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

  10. 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.

  11. 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.

  12. Peroxisome proliferator-activated receptors (PPARs) and PPAR agonists: the 'future' in dermatology therapeutics?

    Science.gov (United States)

    Gupta, Mrinal; Mahajan, Vikram K; Mehta, Karaninder S; Chauhan, Pushpinder S; Rawat, Ritu

    2015-11-01

    Peroxisome proliferator-activated receptors (PPARs) are nuclear hormone receptors and comprise three different isoforms namely PPARα, PPARγ, and PPARβ/δ with PPARβ/δ being the predominant subtype in human keratinocytes. After binding with specific ligands, PPARs regulate gene expression, cell growth and differentiation, apoptosis, inflammatory responses, and tumorogenesis. PPARs also modulate a wide variety of skin functions including keratinocyte proliferation, epidermal barrier formation, wound healing, melanocyte proliferation, and sebum production. Recent studies have shown the importance of PPARs in the pathogenesis of many dermatological disorders. Clinical trials have suggested possible role of PPAR agonists in the management of various dermatoses ranging from acne vulgaris, psoriasis, hirsutism, and lipodystrophy to cutaneous malignancies including melanoma. This article is intended to be a primer for dermatologists in their understanding of clinical relevance of PPARs and PPAR agonists in dermatology therapeutics. PMID:25986745

  13. 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...... 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...

  14. 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

  15. Cannabinoid CB2 Receptor Mediates Nicotine-Induced Anti-Inflammation in N9 Microglial Cells Exposed to β Amyloid via Protein Kinase C

    Directory of Open Access Journals (Sweden)

    Ji Jia

    2016-01-01

    Full Text Available Background. Reducing β amyloid- (Aβ- induced microglial activation is considered to be effective in treating Alzheimer’s disease (AD. Nicotine attenuates Aβ-induced microglial activation; the mechanism, however, is still elusive. Microglia could be activated into classic activated state (M1 state or alternative activated state (M2 state; the former is cytotoxic and the latter is neurotrophic. In this investigation, we hypothesized that nicotine attenuates Aβ-induced microglial activation by shifting microglial M1 to M2 state, and cannabinoid CB2 receptor and protein kinase C mediate the process. Methods. We used Aβ1–42 to activate N9 microglial cells and observed nicotine-induced effects on microglial M1 and M2 biomarkers by using western blot, immunocytochemistry, and enzyme-linked immunosorbent assay (ELISA. Results. We found that nicotine reduced the levels of M1 state markers, including inducible nitric oxide synthase (iNOS expression and tumor necrosis factor α (TNF-α and interleukin- (IL- 6 releases; meanwhile, it increased the levels of M2 state markers, including arginase-1 (Arg-1 expression and brain-derived neurotrophic factor (BDNF release, in the Aβ-stimulated microglia. Coadministration of cannabinoid CB2 receptor antagonist or protein kinase C (PKC inhibitor partially abolished the nicotine-induced effects. Conclusion. These findings indicated that cannabinoid CB2 receptor mediates nicotine-induced anti-inflammation in microglia exposed to Aβ via PKC.

  16. 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

  17. Classical and atypical agonists activate M1 muscarinic acetylcholine receptors through common mechanisms

    Czech Academy of Sciences Publication Activity Database

    Randáková, Alena; Dolejší, Eva; Rudajev, Vladimír; Zimčík, Pavel; Doležal, Vladimír; El-Fakahany, E. E.; Jakubík, Jan

    2015-01-01

    Roč. 97, Jul 2015 (2015), s. 27-39. ISSN 1043-6618 R&D Projects: GA ČR(CZ) GA305/09/0681; GA ČR(CZ) GBP304/12/G069; GA MŠk(CZ) EE2.3.30.0025 Institutional support: RVO:67985823 Keywords : muscarinic acetylcholine receptors * atypical agonists * xanomeline * activation mechanism Subject RIV: ED - Physiology Impact factor: 4.408, year: 2014

  18. Forearm vasodilator responses to a β‐adrenergic receptor agonist in premenopausal and postmenopausal women

    OpenAIRE

    Harvey, Ronee E.; Barnes, Jill N.; Charkoudian, Nisha; Curry, Timothy B.; Eisenach, John H.; Hart, Emma C.; Joyner, Michael J.

    2014-01-01

    Abstract Beta‐adrenergic vasodilator responses may be blunted in humans who are at an increased risk for hypertension. Because menopause is associated with an increase in blood pressure, we tested the hypothesis that forearm blood flow responses to the β‐adrenergic receptor agonist isoproterenol are blunted in older, postmenopausal women compared to young, premenopausal women. We used venous occlusion plethysmography to measure forearm blood flow in young premenopausal (26 ± 1 years; n = 13) ...

  19. 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...

  20. Adenosine and a selective A2a receptor agonist regadenoson used in myocardial stress test

    International Nuclear Information System (INIS)

    Adenosine pharmacological myocardial stress test has been widely used in clinic. However, the side effects related with adenosine administration has been an issue of controversy. Current Phase Ⅲ study of regadenoson, a selective A2a receptor agonist, reveals its potential to substitute adenosine as a new agent for pharmacological myocardial stress test. This review briefs adenosine and regadenoson and their clinical utilities in myocardial stress test. (authors)

  1. Strategies to improve outcome after islet transplantation using the GLP-1 receptor agonist, extendin-4

    OpenAIRE

    Sharma, Amit

    2007-01-01

    Transplantation of pancreatic islets into the liver via the portal vein has emerged as a treatment option for patients with type I diabetes mellitus. However, loss of functional beta cell mass during isolation and following implantation is a major obstacle in obtaining good long-term results. Exendin-4, a glucagonlike peptide-1 (GLP-1) receptor agonist, improves glucose homeostasis in patients with diabetes. It also has anti-apoptotic and beta cell proliferative properties t...

  2. 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...

  3. 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...

  4. Mapping CB1 cannabinoid receptors with [3H]OMAR in the Flinders rodent model of depression

    DEFF Research Database (Denmark)

    Nahimi, A.; Gjedde, A.; Wong, D. F.;

    2012-01-01

    H]OMAR, a highly selective CB1 receptor antagonist (Horti et al, 2006) in the Flinders rodent model of depression. Methods: The Flinders sensitive line (FSL) (N = 5-6) was used as a model of depression and the Flinders resistant line (FRL) (N= 6-8) served as controls (Wegener et al. 2010). In these......Background: The endocannabinoid system regulates cognitive and emotional processes and pathology of this system is implicated in psychiatric disorders, including depression and schizophrenia. The precise role of the endocannabinoid system in psychiatric disorders remains unclear, but changes in...... expression of CB1 receptors and subsequent altered modulation of monoamines is suggested in depression (Esteban & Garcia-Sevilla, 2011). CB1 receptor agonists, such as WIN55,212-2 and CP55,940 regulate synthesis and release of monoamines and are suggested as a novel therapy in the treatment of depression...

  5. Anti-Inflammatory Effects of β2-Receptor Agonists Salbutamol and Terbutaline Are Mediated by MKP-1.

    Science.gov (United States)

    Keränen, Tiina; Hömmö, Tuija; Hämäläinen, Mari; Moilanen, Eeva; Korhonen, Riku

    2016-01-01

    Mitogen-activated protein kinase phosphatase 1 (MKP-1) expression is induced by inflammatory factors, and it is an endogenous suppressor of inflammatory response. MKP-1 expression is increased by PDE4 inhibitor rolipram suggesting that it is regulated by cAMP-enhancing compounds. Therefore, we investigated the effect of β2-receptor agonists on MKP-1 expression and inflammatory response. We found that β2-receptor agonists salbutamol and terbutaline, as well as 8-Br-cAMP, increased MKP-1 expression. Salbutamol and terbutaline also inhibited p38 MAPK phosphorylation and TNF production in J774 mouse macrophages. Interestingly, salbutamol suppressed carrageenan-induced paw inflammation in wild-type mice, but the effect was attenuated in MKP-1(-/-) mice. In conclusion, these data show that β2-receptor agonists increase MKP-1 expression, which seems to mediate, at least partly, the observed anti-inflammatory effects of β2-receptor agonists. PMID:26849227

  6. 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

  7. 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...

  8. 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-...

  9. 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...... weekly, albiglutide once weekly and dulaglutide once weekly. The phase III trial of a seventh GLP-1RA, taspoglutide once weekly, was stopped because of unacceptable adverse events (AEs). Nine phase III head-to-head trials and one large phase II study have compared the efficacy and safety of these seven...

  10. 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...

  11. 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...

  12. 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

  13. Serotonin3 receptor agonists attenuate glutamate-induced firing in rat hippocampal CA1 pyramidal cells.

    Science.gov (United States)

    Zhang, J Y; Zeise, M L; Wang, R Y

    1994-01-01

    The techniques of extracellular single cell recording and microiontophoresis were used to study the effect of 5-HT3 receptor agonists on glutamate-activated firing of CA1 hippocampal pyramidal cells. Iontophoretic application of 5-HT3 receptor agonists 2-methyl-5-HT and SR 57227A produced a current (dose)-dependent suppression of the firing of CA1 pyramidal cells; SR 57227A was more effective than 2-methyl-5-HT. The suppressant action of 2-methyl-5-HT and SR 57227A had a slow onset and showed little or no desensitization. This effect was markedly attenuated or completely blocked by the 5-HT3 receptor antagonist BRL 46470A but not by the nonspecific 5-HT1 and 5-HT2 receptor antagonist metergoline or by the 5-HT1A antagonist WAY 100478. Intravenous administration of SR 57227A was effective in reducing the firing rate of CA1 pyramidal cells and this effect was prevented by BRL 46470A administered either i.v. or iontophoretically. Iontophoresis of 2-methyl-5-HT also diminished CA1 postsynaptic field potentials evoked by electrical stimulation of the Schaffer collaterals. Again, BRL 46470A but not metergoline prevented the suppressant action of 2-methyl-5-HT. Taken together, our results indicate that activation of 5-HT3-like receptors in the hippocampal CA1 region effectively reduces the efficacy of glutamatergic neurotransmission. PMID:7984287

  14. Differential treatment regimen-related effects of cannabinoids on D1 and D2 receptors in adolescent and adult rat brain.

    Science.gov (United States)

    Dalton, Victoria S; Zavitsanou, Katerina

    2010-12-01

    Animal studies suggest differential effects of cannabinoids on dopamine-related behaviours in adolescence and adulthood however few studies have investigated the underlying neurochemical effects of cannabinoids during adolescence. The aim of the present study was to compare the effects of treatment with the synthetic cannabinoid, HU210, on dopamine receptor density in adolescent and adult rats. Adolescent (postnatal day (PND) 35) and adult (PND 70) rats received a single dose of 100μg/kg HU210 or 25, 50 or 100μg/kg HU210 for 4 or 14 days. Dopamine D1 receptor (D1R) or D2 receptor (D2R) density was measured in the medial and lateral (CPUL) caudate putamen, nucleus accumbens, olfactory tubercle (TU) and substantia nigra (D1R only) using in vitro autoradiography. D1R and D2R densities were 1.6-1.7- and 1.1-1.4-fold higher respectively in adolescent control rats compared to adults. In adult rats, D1R density was increased by 1.2- and 1.3-fold (pHU210 treatment. A significant overall effect of treatment (pHU210. In adolescents, an overall effect of treatment on D1R density after a single exposure to HU210 was seen (p=0.0026) but no changes in D1R or D2R densities were observed in other treatment groups. These results suggest that the adolescent rat brain does not display the same compensatory mechanisms activated in the adult brain following cannabinoid treatment. PMID:20673846

  15. 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, tumor number, and the amount/severity of lung metastases in MMTV-neu mice. Histological analyses of the tumors revealed that cannabinoids inhibit cancer cell proliferation, induce cancer cell apoptosis, and impair tumor angiogenesis. Cannabinoid antitumoral action relies, at least partially, on the inhibition of the pro-tumorigenic Akt pathway. We also found that 91% of ErbB2-positive tumors express the non-psychotropic cannabinoid receptor CB2. Conclusions Taken together, these results provide a strong preclinical evidence for the use of cannabinoid-based therapies for the management of ErbB2-positive breast cancer.

  16. 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.

  17. 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...

  18. 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...

  19. Ractopamine, a livestock feed additive, is a full agonist at trace amine-associated receptor 1.

    Science.gov (United States)

    Liu, Xuehong; Grandy, David K; Janowsky, Aaron

    2014-07-01

    Ractopamine (RAC) is fed to an estimated 80% of all beef, swine, and turkey raised in the United States. It promotes muscle mass development, limits fat deposition, and reduces feed consumption. However, it has several undesirable behavioral side effects in livestock, especially pigs, including restlessness, agitation, excessive oral-facial movements, and aggressive behavior. Numerous in vitro and in vivo studies suggest RAC's physiological actions begin with its stimulation of β1- and β2-adrenergic receptor-mediated signaling in skeletal muscle and adipose tissue; however, the molecular pharmacology of RAC's psychoactive effects is poorly understood. Using human cystic fibrosis transmembrane conductance regulator (hCFTR) chloride channels as a sensor for intracellular cAMP, we found that RAC and p-tyramine (TYR) produced concentration-dependent increases in chloride conductance in oocytes coexpressing hCFTR and mouse trace amine-associated receptor 1 (mTAAR1), which was completely reversed by the trace amine-associated receptor 1 (TAAR1)-selective antagonist EPPTB [N-(3-ethoxyphenyl)-4-pyrrolidin-1-yl-3-trifluoromethylbenzamide]. Oocytes coexpressing hCFTR and the human β2-adrenergic receptor showed no response to RAC or TYR. These studies demonstrate that, contrary to expectations, RAC is not an agonist of the human β2-adrenergic receptor but rather a full agonist for mTAAR1. Since TAAR1-mediated signaling can influence cardiovascular tone and behavior in several animal models, our finding that RAC is a full mTAAR1 agonist supports the idea that this novel mechanism of action influences the physiology and behavior of pigs and other species. These findings should stimulate future studies to characterize the pharmacological, physiological, and behavioral actions of RAC in humans and other species exposed to this drug. PMID:24799633

  20. 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

  1. 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

  2. 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

  3. Graft versus host disease: New insights into A2A receptor agonist therapy

    Directory of Open Access Journals (Sweden)

    Karlie R. Jones

    2015-01-01

    Full Text Available Allogeneic transplantation can cure many disorders, including sickle cell disease, chronic granulomatous disease (CGD, severe combined immunodeficiency (SCID and many types of cancers. However, there are several associated risks that can result in severe immunological reactions and, in some cases, death. Much of this morbidity is related to graft versus host disease (GVHD [1]. GVHD is an immune mediated reaction in which donor T cells recognize the host as antigenically foreign, causing donor T cells to expand and attack host tissues. The current method of treating recent transplant patients with immunosuppressants to prevent this reaction has met with only partial success, emphasizing a need for new methods of GVHD treatment and prevention. Recently, a novel strategy has emerged targeting adenosine A2A receptors (A2AR through the use of adenosine agonists. These agonists have been shown in vitro to increase the TGFβ-induced generation of FoxP3+ regulatory T cells (Tregs and in vivo to improve weight gain and mortality as well as inhibit the release of pro-inflammatory cytokines in GVHD murine models [2,3]. Positive results involving A2AR agonists in vitro and in vivo are promising, suggesting that A2AR agonists should be a part of the management of clinical GvHD.

  4. 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

  5. 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

  6. 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.

  7. 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.

  8. 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. PMID:26563389

  9. The cannabinoid CB1 receptor and mTORC1 signalling pathways interact to modulate glucose homeostasis in mice

    Directory of Open Access Journals (Sweden)

    Francisco J. Bermudez-Silva

    2016-01-01

    Full Text Available 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.

  10. 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

  11. 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

  12. 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

  13. Convulsant doses of a dopamine D1 receptor agonist result in Erk-dependent increases in Zif268 and Arc/Arg3.1 expression in mouse dentate gyrus.

    Science.gov (United States)

    Gangarossa, Giuseppe; Di Benedetto, Manuela; O'Sullivan, Gerard J; Dunleavy, Mark; Alcacer, Cristina; Bonito-Oliva, Alessandra; Henshall, David C; Waddington, John L; Valjent, Emmanuel; Fisone, Gilberto

    2011-01-01

    Activation of dopamine D1 receptors (D1Rs) has been shown to induce epileptiform activity. We studied the molecular changes occurring in the hippocampus in response to the administration of the D1-type receptor agonist, SKF 81297. SKF 81297 at 2.5 and 5.0 mg/kg induced behavioural seizures. Electrophysiological recordings in the dentate gyrus revealed the presence of epileptiform discharges peaking at 30-45 min post-injection and declining by 60 min. Seizures were prevented by the D1-type receptor antagonist, SCH 23390, or the cannabinoid CB1 receptor agonist, CP 55,940. The effect of SKF 81297 was accompanied by increased phosphorylation of the extracellular signal-regulated protein kinases 1 and 2 (ERK), in the granule cells of the dentate gyrus. This effect was also observed in response to administration of other D1-type receptor agonists, such as SKF83822 and SKF83959. In addition, SKF 81297 increased the phosphorylation of the ribosomal protein S6 and histone H3, two downstream targets of ERK. These effects were prevented by genetic inactivation of D1Rs, or by pharmacological inhibition of ERK. SKF 81297 was also able to enhance the levels of Zif268 and Arc/Arg3.1, two immediate early genes involved in transcriptional regulation and synaptic plasticity. These changes may be involved in forms of activity-dependent plasticity linked to the manifestation of seizures and to the ability of dopamine to affect learning and memory. PMID:21559295

  14. 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

  15. 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.

  16. 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

  17. Type 1 cannabinoid receptor mapping with [18F]MK-9470 PET in the rat brain after quinolinic acid lesion: a comparison to dopamine receptors and glucose metabolism

    International Nuclear Information System (INIS)

    Several lines of evidence imply early alterations in metabolic, dopaminergic and endocannabinoid neurotransmission in Huntington's disease (HD). Using [18F]MK-9470 and small animal PET, we investigated cerebral changes in type 1 cannabinoid (CB1) receptor binding in the quinolinic acid (QA) rat model of HD in relation to glucose metabolism, dopamine D2 receptor availability and amphetamine-induced turning behaviour. Twenty-one Wistar rats (11 QA and 10 shams) were investigated. Small animal PET acquisitions were conducted on a Focus 220 with approximately 18 MBq of [18F]MK-9470, [18F]FDG and [11C]raclopride. Relative glucose metabolism and parametric CB1 receptor and D2 binding images were anatomically standardized to Paxinos space and analysed voxel-wise using Statistical Parametric Mapping (SPM2). In the QA model, [18F]MK-9470 uptake, glucose metabolism and D2 receptor binding were reduced in the ipsilateral caudate-putamen by 7, 35 and 77%, respectively (all p -5), while an increase for these markers was observed on the contralateral side (>5%, all p -4). [18F]MK-9470 binding was also increased in the cerebellum (p = 2.10-5), where it was inversely correlated to the number of ipsiversive turnings (p = 7.10-6), suggesting that CB1 receptor upregulation in the cerebellum is related to a better functional outcome. Additionally, glucose metabolism was relatively increased in the contralateral hippocampus, thalamus and sensorimotor cortex (p = 1.10-6). These data point to in vivo changes in endocannabinoid transmission, specifically for CB1 receptors in the QA model, with involvement of the caudate-putamen, but also distant regions of the motor circuitry, including the cerebellum. These data also indicate the occurrence of functional plasticity on metabolism, D2 and CB1 neurotransmission in the contralateral hemisphere. (orig.)

  18. 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

  19. Overlapping binding site for the endogenous agonist, small-molecule agonists, and ago-allosteric modulators on the ghrelin receptor

    DEFF Research Database (Denmark)

    Holst, Birgitte; Frimurer, Thomas M; Mokrosinski, Jacek;

    2008-01-01

    mutational map for agonism but it was not identical with the map for the agonist property of these small-molecule ligands. In molecular models, built over the inactive conformation of rhodopsin, low energy conformations of the nonpeptide agonists could be docked to satisfy many of their mutational hits. It...

  20. Cannabinoid Receptor-2 Regulates Embryonic Hematopoietic Stem Cell Development via Prostaglandin E2 and P-Selectin Activity.

    Science.gov (United States)

    Esain, Virginie; Kwan, Wanda; Carroll, Kelli J; Cortes, Mauricio; Liu, Sarah Y; Frechette, Gregory M; Sheward, Lea M V; Nissim, Sahar; Goessling, Wolfram; North, Trista E

    2015-08-01

    Cannabinoids (CB) modulate adult hematopoietic stem and progenitor cell (HSPCs) function, however, impact on the production, expansion, or migration of embryonic HSCs is currently uncharacterized. Here, using chemical and genetic approaches targeting CB-signaling in zebrafish, we show that CB receptor (CNR) 2, but not CNR1, regulates embryonic HSC development. During HSC specification in the aorta-gonad-mesonephros (AGM) region, CNR2 stimulation by AM1241 increased runx1;cmyb(+) HSPCs, through heightened proliferation, whereas CNR2 antagonism decreased HSPC number; FACS analysis and absolute HSC counts confirmed and quantified these effects. Epistatic investigations showed AM1241 significantly upregulated PGE2 synthesis in a Ptgs2-dependent manner to increase AGM HSCs. During the phases of HSC production and colonization of secondary niches, AM1241 accelerated migration to the caudal hematopoietic tissue (CHT), the site of embryonic HSC expansion, and the thymus; however these effects occurred independently of PGE2. Using a candidate approach for HSC migration and retention factors, P-selectin was identified as the functional target of CNR2 regulation. Epistatic analyses confirmed migration of HSCs into the CHT and thymus was dependent on CNR2-regulated P-selectin activity. Together, these data suggest CNR2-signaling optimizes the production, expansion, and migration of embryonic HSCs by modulating multiple downstream signaling pathways. PMID:25931248

  1. Fasting induces CART down-regulation in the zebrafish nervous system in a cannabinoid receptor 1-dependent manner.

    Science.gov (United States)

    Nishio, Shin-Ichi; Gibert, Yann; Berekelya, Liubov; Bernard, Laure; Brunet, Frédéric; Guillot, Etienne; Le Bail, Jean-Christophe; Sánchez, Juan Antonio; Galzin, Anne Marie; Triqueneaux, Gerard; Laudet, Vincent

    2012-08-01

    Central and peripheral mechanisms modulate food intake and energy balance in mammals and the precise role of the type 1 cannabinoid receptor (CB1) in these processes is still being explored. Using the zebrafish, Danio rerio, we show that rimonabant, a CB1-specific antagonist with an EC(50) of 5.15 × 10(-8) m, decreases embryonic yolk sac reserve use. We reveal a developmental overlap between CART genes and CB1 expression in the hypothalamus and medulla oblongata, two brain structures that play crucial roles in appetite regulation in mammals. We show that morpholino knockdown of CB1 or fasting decreases cocaine- and amphetamine-related transcript (CART)-3 expression. Strikingly, this down-regulation occurs only in regions coexpressing CB1 and CART3, reinforcing the link between CB1, CART, and appetite regulation. We show that rimonabant treatment impairs the fasting-induced down-regulation of CART expression in specific brain regions, whereas vehicle alone-treated embryos do not display this rescue of CART expression. Our data reveal that CB1 lies upstream of CART and signals the appetite through the down-regulation of CART expression. Thus, our results establish the zebrafish as a promising system to study appetite regulation. PMID:22700585

  2. Ractopamine, a Livestock Feed Additive, Is a Full Agonist at Trace Amine–Associated Receptor 1

    Science.gov (United States)

    Grandy, David K.; Janowsky, Aaron

    2014-01-01

    Ractopamine (RAC) is fed to an estimated 80% of all beef, swine, and turkey raised in the United States. It promotes muscle mass development, limits fat deposition, and reduces feed consumption. However, it has several undesirable behavioral side effects in livestock, especially pigs, including restlessness, agitation, excessive oral-facial movements, and aggressive behavior. Numerous in vitro and in vivo studies suggest RAC’s physiological actions begin with its stimulation of β1- and β2-adrenergic receptor–mediated signaling in skeletal muscle and adipose tissue; however, the molecular pharmacology of RAC’s psychoactive effects is poorly understood. Using human cystic fibrosis transmembrane conductance regulator (hCFTR) chloride channels as a sensor for intracellular cAMP, we found that RAC and p-tyramine (TYR) produced concentration-dependent increases in chloride conductance in oocytes coexpressing hCFTR and mouse trace amine–associated receptor 1 (mTAAR1), which was completely reversed by the trace amine–associated receptor 1 (TAAR1)–selective antagonist EPPTB [N-(3-ethoxyphenyl)-4-pyrrolidin-1-yl-3-trifluoromethylbenzamide]. Oocytes coexpressing hCFTR and the human β2-adrenergic receptor showed no response to RAC or TYR. These studies demonstrate that, contrary to expectations, RAC is not an agonist of the human β2-adrenergic receptor but rather a full agonist for mTAAR1. Since TAAR1-mediated signaling can influence cardiovascular tone and behavior in several animal models, our finding that RAC is a full mTAAR1 agonist supports the idea that this novel mechanism of action influences the physiology and behavior of pigs and other species. These findings should stimulate future studies to characterize the pharmacological, physiological, and behavioral actions of RAC in humans and other species exposed to this drug. PMID:24799633

  3. 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

  4. A Monoclonal Antibody with Thyrotropin (TSH) Receptor Inverse Agonist and TSH Antagonist Activities Binds to the Receptor Hinge Region as Well as to the Leucine-Rich Domain

    OpenAIRE

    Chen, Chun-Rong; McLachlan, Sandra M.; Rapoport, Basil

    2009-01-01

    Monoclonal antibody CS-17 is a TSH receptor (TSHR) inverse agonist (suppresses constitutive activity) and a TSH antagonist. Elucidation of the CS-17 epitope will provide insight into TSHR structure and function. Present information on its epitope conflicts with recent data regarding another TSHR inverse agonist antibody. To characterize further the CS-17 epitope, we exploited the observation that CS-17 does not recognize a chimeric receptor with TSHR hinge region residues 261–289 replaced wit...

  5. 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

  6. 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

  7. Affinity and kinetics study of anthranilic acids as HCA2 receptor agonists.

    Science.gov (United States)

    van Veldhoven, Jacobus P D; Liu, Rongfang; Thee, Stephanie A; Wouters, Yessica; Verhoork, Sanne J M; Mooiman, Christiaan; Louvel, Julien; IJzerman, Adriaan P

    2015-07-15

    Structure-affinity relationship (SAR) and structure-kinetics relationship (SKR) studies were combined to investigate a series of biphenyl anthranilic acid agonists for the HCA2 receptor. In total, 27 compounds were synthesized and twelve of them showed higher affinity than nicotinic acid. Two compounds, 6g (IC50=75nM) and 6z (IC50=108nM) showed a longer residence time profile compared to nicotinic acid, exemplified by their kinetic rate index (KRI) values of 1.31 and 1.23, respectively. The SAR study resulted in the novel 2-F, 4-OH derivative (6x) with an IC50 value of 23nM as the highest affinity HCA2 agonist of the biphenyl series, although it showed a similar residence time as nicotinic acid. The SAR and SKR data suggest that an early compound selection based on binding kinetics is a promising addition to the lead optimization process. PMID:25737085

  8. 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.

  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. 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

  11. 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.

  12. 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

    GPR132 is an orphan class A G protein-coupled receptor. It has been proposed to be activated by protons and to regulate apoptosis, atherosclerosis and inflammation, but these results are still preliminary. In the current work, we designed and screened a focused compound library using a β-arrestin......GPR132 is an orphan class A G protein-coupled receptor. It has been proposed to be activated by protons and to regulate apoptosis, atherosclerosis and inflammation, but these results are still preliminary. In the current work, we designed and screened a focused compound library using a β......-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...

  13. 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.

  14. 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...

  15. Multiresidue Method for Analysis of β Agonists in Swine Urine by Enzyme Linked Receptor Assay Based on β2 Adrenergic Receptor Expressed in HEK293 Cells

    OpenAIRE

    Wang, Jian; She, Yongxin; Wang, Miao; Jin, Maojun; Li, Yongfei; Wang, Jing; Liu, Yuan

    2015-01-01

    A novel enzyme-linked receptor assay (ELRA) based on β2-adrenergic receptor (β2-AR) has been developed for rapid and high-throughput detection of β-adrenergic agonists (β-agonists) in urine. Human embryonic kidney cells (HEK293) were introduced as the expression system to enhance the functionality of the recombinant β2-AR, and the attempt to detect β-agonists in swine urine using such approaches was accomplished unprecedentedly. In this article, a recombinant porcine β2-AR was produced in the...

  16. The Cannabinoid Receptor 2 Q63R Variant Modulates the Relationship between Childhood Obesity and Age at Menarche.

    Directory of Open Access Journals (Sweden)

    Giulia Bellini

    Full Text Available The ovary is an important site where gene variants modulate pubertal timing. The cannabinoid receptor 2 (CB2 is expressed in the ovary, plays a role in folliculogenesis and ovulation, and can be modulated by estrogens. Obesity is strictly associated with early menarche and is characterized by sex hormone and endocannabinoid derangement.In this study, we investigated the role of the CB2 receptor in determining the age at menarche in obese girls.We studied a cohort of 240 obese girls (age 11.9±3 years; BMI z-score 2.8±0.8. The age at menarche (if it had already occurred was recorded at the time of the visit or via phonecall. The CNR2 rs35761398 polymorphism, which leads to the CB2 Q63R variant, was detected by the TaqMan assay.In total, 105 patients were homozygous for the R63-coding allele (RR, 113 were QR and 22 were QQ. Variance analysis revealed a significantly earlier age of menarche in subjects carrying the Q63 allele, which was also found after adjusting for BMI z-score (11±1.2 vs. 11.6±1.2 years, p = 0.0003. Logistic regression analysis demonstrated that patients homozygous for the Q allele had a 2.2-fold higher risk (odds ratio = 2.2; CI1.1-3.4; p = 0.02 of presenting with an early menarche (age at menarche <12 years.We demonstrated for the first time the association between the CB2 Q63R functional variant and the age at menarche in a cohort of Italian obese girls.

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

    Directory of Open Access Journals (Sweden)

    Oosterveer Maaike H

    2011-12-01

    Full Text Available Abstract 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 quantified lipogenic and lipolytic activities in fat tissues of CB1-/- and CB1+/+ mice fed a high-fat (HF or a high-fat/fish oil (HF/FO diet as compared to animals receiving a low-fat chow diet. Comparison between HF diet and HF/FO diet allowed to investigate the influence of dietary fat quality on adipose tissue biology in relation to CB1 functioning. Results The adiposity-resistant phenotype of the CB1-/- mice was characterized by reduced fat mass and adipocyte size in HF and HF/FO-fed CB1-/- mice in parallel to a significant increase in energy expenditure as compared to CB1+/+ mice. The expression levels of adipocyte differentiation and proliferation markers were however maintained in these animals. Consistent with unaltered lipogenic gene expression, the fatty acid synthesis rates in adipose tissues from CB1-/- and CB1+/+ mice were unchanged. Whole-body and adipose-specific lipoprotein lipase (LPL activities were also not altered in CB1-/- mice. Conclusions These findings indicate that protection against diet-induced adiposity in CB1-deficient mice is not related to changes in adipocyte function per se, but rather results from increased energy dissipation by oxidative and non-oxidative pathways.

  18. Small-animal PET imaging of the type 1 and type 2 cannabinoid receptors in a photothrombotic stroke model

    Energy Technology Data Exchange (ETDEWEB)

    Vandeputte, Caroline; Casteels, Cindy; Koole, Michel; Gerits, Anneleen [KU Leuven, Division of Nuclear Medicine, Leuven (Belgium); KU Leuven, Molecular Small Animal Imaging Center, MoSAIC, Leuven (Belgium); Struys, Tom [Hasselt University, Laboratory of Histology, Biomedical Research Institute, Hasselt (Belgium); KU Leuven, Biomedical NMR Unit, Leuven (Belgium); Veghel, Daisy van; Evens, Nele; Bormans, Guy [KU Leuven, Molecular Small Animal Imaging Center, MoSAIC, Leuven (Belgium); KU Leuven, Laboratory of Radiopharmacy, Leuven (Belgium); Dresselaers, Tom; Himmelreich, Uwe [KU Leuven, Molecular Small Animal Imaging Center, MoSAIC, Leuven (Belgium); KU Leuven, Biomedical NMR Unit, Leuven (Belgium); Lambrichts, Ivo [Hasselt University, Laboratory of Histology, Biomedical Research Institute, Hasselt (Belgium); Laere, Koen van [KU Leuven, Division of Nuclear Medicine, Leuven (Belgium); KU Leuven, Molecular Small Animal Imaging Center, MoSAIC, Leuven (Belgium); UZ Leuven, Division of Nuclear Medicine, Leuven (Belgium)

    2012-11-15

    Recent ex vivo and pharmacological evidence suggests involvement of the endocannabinoid system in the pathophysiology of stroke, but conflicting roles for type 1 and 2 cannabinoid receptors (CB{sub 1} and CB{sub 2}) have been suggested. The purpose of this study was to evaluate CB{sub 1} and CB{sub 2} receptor binding over time in vivo in a rat photothrombotic stroke model using PET. CB{sub 1} and CB{sub 2} microPET imaging was performed at regular time-points up to 2 weeks after stroke using [{sup 18}F]MK-9470 and [{sup 11}C]NE40. Stroke size was measured using MRI at 9.4 T. Ex vivo validation was performed via immunostaining for CB{sub 1} and CB{sub 2}. Immunofluorescent double stainings were also performed with markers for astrocytes (GFAP) and macrophages/microglia (CD68). [{sup 18}F]MK-9470 PET showed a strong increase in CB{sub 1} binding 24 h and 72 h after stroke in the cortex surrounding the lesion, extending to the insular cortex 24 h after surgery. These alterations were consistently confirmed by CB{sub 1} immunohistochemical staining. [{sup 11}C]NE40 did not show any significant differences between stroke and sham-operated animals, although staining for CB{sub 2} revealed minor immunoreactivity at 1 and 2 weeks after stroke in this model. Both CB{sub 1} {sup +} and CB{sub 2} {sup +} cells showed minor immunoreactivity for CD68. Time-dependent and regionally strongly increased CB{sub 1}, but not CB{sub 2}, binding are early consequences of photothrombotic stroke. Pharmacological interventions should primarily aim at CB{sub 1} signalling as the role of CB{sub 2} seems minor in the acute and subacute phases of stroke. (orig.)

  19. Impaired Ethanol-Induced Sensitization and Decreased Cannabinoid Receptor-1 in a Model of Posttraumatic Stress Disorder

    Science.gov (United States)

    Matchynski-Franks, Jessica J.; Susick, Laura L.; Schneider, Brandy L.; Perrine, Shane A.; Conti, Alana C.

    2016-01-01

    Background and Purpose Impaired striatal neuroplasticity may underlie increased alcoholism documented in those with posttraumatic stress disorder (PTSD). Cannabinoid receptor-1 (CB1) is sensitive to the effects of ethanol (EtOH) and traumatic stress, and is a critical regulator of striatal plasticity. To investigate CB1 involvement in the PTSD-alcohol interaction, this study measured the effects of traumatic stress using a model of PTSD, mouse single-prolonged stress (mSPS), on EtOH-induced locomotor sensitization and striatal CB1 levels. Methods Mice were exposed to mSPS, which includes: 2-h restraint, 10-min group forced swim, 15-min exposure to rat bedding odor, and diethyl ether exposure until unconsciousness or control conditions. Seven days following mSPS exposure, the locomotor sensitizing effects of EtOH were assessed. CB1, post-synaptic density-95 (PSD95), and dopamine-2 receptor (D2) protein levels were then quantified in the dorsal striatum using standard immunoblotting techniques. Results Mice exposed to mSPS-EtOH demonstrated impaired EtOH-induced locomotor sensitization compared to Control-EtOH mice, which was accompanied by reduced striatal CB1 levels. EtOH increased striatal PSD95 in control and mSPS-exposed mice. Additionally, mSPS-Saline exposure increased striatal PSD95 and decreased D2 protein expression, with mSPS-EtOH exposure alleviating these changes. Conclusions These data indicate that the mSPS model of PTSD blunts the behavioral sensitizing effects of EtOH, a response that suggests impaired striatal neuroplasticity. Additionally, this study demonstrates that mice exposed to mSPS and repeated EtOH exposure decreases CB1 in the striatum, providing a mechanism of interest for understanding the effects of EtOH following severe, multimodal stress exposure. PMID:27186643

  20. Evaluation of MRI and cannabinoid type 1 receptor PET templates constructed using DARTEL for spatial normalization of rat brains

    Energy Technology Data Exchange (ETDEWEB)

    Kronfeld, Andrea; Müller-Forell, Wibke [Institute of Neuroradiology, University Medical Center of the Johannes Gutenberg University Mainz, Langenbeckstraße 1, Mainz 55131 (Germany); Buchholz, Hans-Georg; Maus, Stephan; Reuss, Stefan; Schreckenberger, Mathias; Miederer, Isabelle, E-mail: isabelle.miederer@unimedizin-mainz.de [Department of Nuclear Medicine, University Medical Center of the Johannes Gutenberg University Mainz, Langenbeckstraße 1, Mainz 55131 (Germany); Lutz, Beat [Institute of Physiological Chemistry, University Medical Center of the Johannes Gutenberg University Mainz, Duesbergweg 6, Mainz 55128 (Germany)

    2015-12-15

    Purpose: Image registration is one prerequisite for the analysis of brain regions in magnetic-resonance-imaging (MRI) or positron-emission-tomography (PET) studies. Diffeomorphic anatomical registration through exponentiated Lie algebra (DARTEL) is a nonlinear, diffeomorphic algorithm for image registration and construction of image templates. The goal of this small animal study was (1) the evaluation of a MRI and calculation of several cannabinoid type 1 (CB1) receptor PET templates constructed using DARTEL and (2) the analysis of the image registration accuracy of MR and PET images to their DARTEL templates with reference to analytical and iterative PET reconstruction algorithms. Methods: Five male Sprague Dawley rats were investigated for template construction using MRI and [{sup 18}F]MK-9470 PET for CB1 receptor representation. PET images were reconstructed using the algorithms filtered back-projection, ordered subset expectation maximization in 2D, and maximum a posteriori in 3D. Landmarks were defined on each MR image, and templates were constructed under different settings, i.e., based on different tissue class images [gray matter (GM), white matter (WM), and GM + WM] and regularization forms (“linear elastic energy,” “membrane energy,” and “bending energy”). Registration accuracy for MRI and PET templates was evaluated by means of the distance between landmark coordinates. Results: The best MRI template was constructed based on gray and white matter images and the regularization form linear elastic energy. In this case, most distances between landmark coordinates were <1 mm. Accordingly, MRI-based spatial normalization was most accurate, but results of the PET-based spatial normalization were quite comparable. Conclusions: Image registration using DARTEL provides a standardized and automatic framework for small animal brain data analysis. The authors were able to show that this method works with high reliability and validity. Using DARTEL

  1. Evaluation of MRI and cannabinoid type 1 receptor PET templates constructed using DARTEL for spatial normalization of rat brains

    International Nuclear Information System (INIS)

    Purpose: Image registration is one prerequisite for the analysis of brain regions in magnetic-resonance-imaging (MRI) or positron-emission-tomography (PET) studies. Diffeomorphic anatomical registration through exponentiated Lie algebra (DARTEL) is a nonlinear, diffeomorphic algorithm for image registration and construction of image templates. The goal of this small animal study was (1) the evaluation of a MRI and calculation of several cannabinoid type 1 (CB1) receptor PET templates constructed using DARTEL and (2) the analysis of the image registration accuracy of MR and PET images to their DARTEL templates with reference to analytical and iterative PET reconstruction algorithms. Methods: Five male Sprague Dawley rats were investigated for template construction using MRI and [18F]MK-9470 PET for CB1 receptor representation. PET images were reconstructed using the algorithms filtered back-projection, ordered subset expectation maximization in 2D, and maximum a posteriori in 3D. Landmarks were defined on each MR image, and templates were constructed under different settings, i.e., based on different tissue class images [gray matter (GM), white matter (WM), and GM + WM] and regularization forms (“linear elastic energy,” “membrane energy,” and “bending energy”). Registration accuracy for MRI and PET templates was evaluated by means of the distance between landmark coordinates. Results: The best MRI template was constructed based on gray and white matter images and the regularization form linear elastic energy. In this case, most distances between landmark coordinates were <1 mm. Accordingly, MRI-based spatial normalization was most accurate, but results of the PET-based spatial normalization were quite comparable. Conclusions: Image registration using DARTEL provides a standardized and automatic framework for small animal brain data analysis. The authors were able to show that this method works with high reliability and validity. Using DARTEL templates

  2. Small-animal PET imaging of the type 1 and type 2 cannabinoid receptors in a photothrombotic stroke model

    International Nuclear Information System (INIS)

    Recent ex vivo and pharmacological evidence suggests involvement of the endocannabinoid system in the pathophysiology of stroke, but conflicting roles for type 1 and 2 cannabinoid receptors (CB1 and CB2) have been suggested. The purpose of this study was to evaluate CB1 and CB2 receptor binding over time in vivo in a rat photothrombotic stroke model using PET. CB1 and CB2 microPET imaging was performed at regular time-points up to 2 weeks after stroke using [18F]MK-9470 and [11C]NE40. Stroke size was measured using MRI at 9.4 T. Ex vivo validation was performed via immunostaining for CB1 and CB2. Immunofluorescent double stainings were also performed with markers for astrocytes (GFAP) and macrophages/microglia (CD68). [18F]MK-9470 PET showed a strong increase in CB1 binding 24 h and 72 h after stroke in the cortex surrounding the lesion, extending to the insular cortex 24 h after surgery. These alterations were consistently confirmed by CB1 immunohistochemical staining. [11C]NE40 did not show any significant differences between stroke and sham-operated animals, although staining for CB2 revealed minor immunoreactivity at 1 and 2 weeks after stroke in this model. Both CB1+ and CB2+ cells showed minor immunoreactivity for CD68. Time-dependent and regionally strongly increased CB1, but not CB2, binding are early consequences of photothrombotic stroke. Pharmacological interventions should primarily aim at CB1 signalling as the role of CB2 seems minor in the acute and subacute phases of stroke. (orig.)

  3. Effect of the Cannabinoid Receptor-1 antagonist SR141716A on human adipocyte inflammatory profile and differentiation

    Directory of Open Access Journals (Sweden)

    Murumalla Ravi

    2011-11-01

    Full Text Available Abstract Background Obesity is characterized by inflammation, caused by increase in proinflammatory cytokines, a key factor for the development of insulin resistance. SR141716A, a cannabinoid receptor 1 (CB1 antagonist, shows significant improvement in clinical status of obese/diabetic patients. Therefore, we studied the effect of SR141716A on human adipocyte inflammatory profile and differentiation. Methods Adipocytes were obtained from liposuction. Stromal vascular cells were extracted and differentiated into adipocytes. Media and cells were collected for secretory (ELISA and expression analysis (qPCR. Triglyceride accumulation was observed using oil red-O staining. Cholesterol was assayed by a fluorometric method. 2-AG and anandamide were quantified using isotope dilution LC-MS. TLR-binding experiments have been conducted in HEK-Blue cells. Results In LPS-treated mature adipocytes, SR141716A was able to decrease the expression and secretion of TNF-a. This molecule has the same effect in LPS-induced IL-6 secretion, while IL-6 expression is not changed. Concerning MCP-1, the basal level is down-regulated by SR141716A, but not the LPS-induced level. This effect is not caused by a binding of the molecule to TLR4 (LPS receptor. Moreover, SR141716A restored adiponectin secretion to normal levels after LPS treatment. Lastly, no effect of SR141716A was detected on human pre-adipocyte differentiation, although the compound enhanced adiponectin gene expression, but not secretion, in differentiated pre-adipocytes. Conclusion We show for the first time that some clinical effects of SR141716A are probably directly related to its anti-inflammatory effect on mature adipocytes. This fact reinforces that adipose tissue is an important target in the development of tools to treat the metabolic syndrome.

  4. Cannabinoids for Symptom Management and Cancer Therapy: The Evidence.

    Science.gov (United States)

    Davis, Mellar P

    2016-07-01

    Cannabinoids bind not only to classical receptors (CB1 and CB2) but also to certain orphan receptors (GPR55 and GPR119), ion channels (transient receptor potential vanilloid), and peroxisome proliferator-activated receptors. Cannabinoids are known to modulate a multitude of monoamine receptors. Structurally, there are 3 groups of cannabinoids. Multiple studies, most of which are of moderate to low quality, demonstrate that tetrahydrocannabinol (THC) and oromucosal cannabinoid combinations of THC and cannabidiol (CBD) modestly reduce cancer pain. Dronabinol and nabilone are better antiemetics for chemotherapy-induced nausea and vomiting (CINV) than certain neuroleptics, but are not better than serotonin receptor antagonists in reducing delayed emesis, and cannabinoids have largely been superseded by neurokinin-1 receptor antagonists and olanzapine; both cannabinoids have been recommended for breakthrough nausea and vomiting among other antiemetics. Dronabinol is ineffective in ameliorating cancer anorexia but does improve associated cancer-related dysgeusia. Multiple cancers express cannabinoid receptors directly related to the degree of anaplasia and grade of tumor. Preclinical in vitro and in vivo studies suggest that cannabinoids may have anticancer activity. Paradoxically, cannabinoid receptor antagonists also have antitumor activity. There are few randomized smoked or vaporized cannabis trials in cancer on which to judge the benefits of these forms of cannabinoids on symptoms and the clinical course of cancer. Smoked cannabis has been found to contain Aspergillosis. Immunosuppressed patients should be advised of the risks of using "medical marijuana" in this regard. PMID:27407130

  5. CB2 cannabinoid receptors contribute to bacterial invasion and mortality in polymicrobial sepsis.

    Directory of Open Access Journals (Sweden)

    Balázs Csóka

    Full Text Available BACKGROUND: Sepsis is a major healthcare problem and current estimates suggest that the incidence of sepsis is approximately 750,000 annually. Sepsis is caused by an inability of the immune system to eliminate invading pathogens. It was recently proposed that endogenous mediators produced during sepsis can contribute to the immune dysfunction that is observed in sepsis. Endocannabinoids that are produced excessively in sepsis are potential factors leading to immune dysfunction, because they suppress immune cell function by binding to G-protein-coupled CB(2 receptors on immune cells. Here we examined the role of CB(2 receptors in regulating the host's response to sepsis. METHODS AND FINDINGS: The role of CB(2 receptors was studied by subjecting CB(2 receptor wild-type and knockout mice to bacterial sepsis induced by cecal ligation and puncture. We report that CB(2 receptor inactivation by knockout decreases sepsis-induced mortality, and bacterial translocation into the bloodstream of septic animals. Furthermore, CB(2 receptor inactivation decreases kidney and muscle injury, suppresses splenic nuclear factor (NF-kappaB activation, and diminishes the production of IL-10, IL-6 and MIP-2. Finally, CB(2 receptor deficiency prevents apoptosis in lymphoid organs and augments the number of CD11b(+ and CD19(+ cells during CLP. CONCLUSIONS: Taken together, our results establish for the first time that CB(2 receptors are important contributors to septic immune dysfunction and mortality, indicating that CB(2 receptors may be therapeutically targeted for the benefit of patients suffering from sepsis.

  6. The pain receptor TRPV1 displays agonist-dependent activation stoichiometry.

    Science.gov (United States)

    Hazan, Adina; Kumar, Rakesh; Matzner, Henry; Priel, Avi

    2015-01-01

    The receptor channel TRPV1 (Transient Receptor Potential Vanilloid 1) is expressed by primary afferent sensory neurons of the pain pathway, where it functions as a sensor of noxious heat and various chemicals, including eicosanoids, capsaicin, protons and peptide toxins. Comprised of four identical subunits that organize into a non-selective cationic permeable channel, this receptor has a variety of binding sites responsible for detecting their respective agonists. Although its physiological role as a chemosensor has been described in detail, the stoichiometry of TRPV1 activation by its different ligands remains unknown. Here, we combined the use of concatemeric constructs harboring mutated binding sites with patch-clamp recordings in order to determine the stoichiometry for TRPV1 activation through the vanilloid binding site and the outer-pore domain by capsaicin and protons, respectively. We show that, while a single capsaicin-bound subunit was sufficient to achieve a maximal open-channel lifetime, all four proton-binding sites were required. Thus, our results demonstrate a distinct stoichiometry of TRPV1 activation through two of its different agonist-binding domains. PMID:26194846

  7. 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...

  8. 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...

  9. 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; Jensen, Anders Asbjørn

    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...

  10. 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...

  11. 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

  12. 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...

  13. 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

  14. Neuritogenic and Neuroprotective Properties of Peptide Agonists of the Fibroblast Growth Factor Receptor

    Directory of Open Access Journals (Sweden)

    Shizhong Li

    2010-05-01

    Full Text Available 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 of protein structure, in silico modeling and biological studies have recently resulted in the identification of FGFR binding peptides derived from various FGFs and NCAM mimicking the effects of these molecules with regard to their neuritogenic and neuroprotective properties. This review focuses on recently developed functional peptide agonists of FGFR with possible therapeutic potential.

  15. 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...

  16. 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 ...

  17. 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 J; Vilsboll, Tina

    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...... pancreatic beta-cell-preserving actions. In patients with T2DM, subcutaneously administered lixisenatide displayed linear pharmacokinetics. In two phase II clinical trials, lixisenatide improved glucose tolerance, resulted in weight loss and lowered HbA1C, thereby causing significantly more patients to...

  18. 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.

  19. 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

  20. 4-Methylenesterols from Theonella swinhoei sponge are natural pregnane-X-receptor agonists and farnesoid-X-receptor antagonists that modulate innate immunity

    OpenAIRE

    S. Marino; Ummarino, R.; D'Auria, M.V.; Chini, M.G.; G. Bifulco; D' Amore, C.; Renga, B.; Mencarelli, A; Petek, Sylvain; Fiorucci, S.; Zampella, A.

    2012-01-01

    We report the isolation and the structural elucidation of a family of polyhydroxylated steroids from the marine sponge Theonella swinhoei. Decodification of interactions of these family with nuclear receptors shows that these steroids are potent agonists of human pregnane-X-receptor (PXR) and antagonists of human farnesoid-X-receptor (FXR) with the putative binding mode to nuclear receptors (NRs) obtained through docking experiments. By using monocytes isolated from transgenic mice harboring ...

  1. Identification of Natural Compound Carnosol as a Novel TRPA1 Receptor Agonist

    Directory of Open Access Journals (Sweden)

    Chenxi Zhai

    2014-11-01

    Full Text Available The transient receptor potential ankyrin 1 (TRPA1 cation channel is one of the well-known targets for pain therapy. Herbal medicine is a rich source for new drugs and potentially useful therapeutic agents. To discover novel natural TRPA1 agonists, compounds isolated from Chinese herbs were screened using a cell-based calcium mobilization assay. Out of the 158 natural compounds derived from traditional Chinese herbal medicines, carnosol was identified as a novel agonist of TRPA1 with an EC50 value of 12.46 µM. And the agonistic effect of carnosol on TRPA1 could be blocked by A-967079, a selective TRPA1 antagonist. Furthermore, the specificity of carnosol was verified as it showed no significant effects on two other typical targets of TRP family member: TRPM8 and TRPV3. Carnosol exhibited anti-inflammatory and anti-nociceptive properties; the activation of TRPA1 might be responsible for the modulation of inflammatory nociceptive transmission. Collectively, our findings indicate that carnosol is a new anti-nociceptive agent targeting TRPA1 that can be used to explore further biological role in pain therapy.

  2. Selective Estrogen Receptor β Agonist LY500307 as a Novel Therapeutic Agent for Glioblastoma.

    Science.gov (United States)

    Sareddy, Gangadhara R; Li, Xiaonan; Liu, Jinyou; Viswanadhapalli, Suryavathi; Garcia, Lauren; Gruslova, Aleksandra; Cavazos, David; Garcia, Mike; Strom, Anders M; Gustafsson, Jan-Ake; Tekmal, Rajeshwar Rao; Brenner, Andrew; Vadlamudi, Ratna K

    2016-01-01

    Glioblastomas (GBM), deadly brain tumors, have greater incidence in males than females. Epidemiological evidence supports a tumor suppressive role of estrogen; however, estrogen as a potential therapy for GBM is limited due to safety concerns. Since GBM express ERβ, a second receptor for estrogen, targeting ERβ with a selective agonist may be a potential novel GBM therapy. In the present study, we examined the therapeutic effect of the selective synthetic ERβ agonist LY500307 using in vitro and in vivo GBM models. Treatment with LY500307 significantly reduced the proliferation of GBM cells with no activity on normal astrocytes in vitro. ERβ agonists promoted apoptosis of GBM cells, and mechanistic studies using RNA sequencing revealed that LY500307 modulated several pathways related to apoptosis, cell cycle, and DNA damage response. Further, LY500307 sensitized GBM cells to several FDA-approved chemotherapeutic drugs including cisplatin, lomustine and temozolomide. LY500307 treatment significantly reduced the in vivo tumor growth and promoted apoptosis of GBM tumors in an orthotopic model and improved the overall survival of tumor-bearing mice in the GL26 syngeneic glioma model. Our results demonstrate that LY500307 has potential as a therapeutic agent for GBM. PMID:27126081

  3. Activation of human tonsil and skin mast cells by agonists of proteinase activated receptor-2

    Institute of Scientific and Technical Information of China (English)

    Shao-heng HE; Hua XIE; Yi-ling FU

    2005-01-01

    Aim: To investigate the effects of the agonists of proteinase activated receptor (PAR)-2,and histamine on degranulation of human mast cells. Methods: Human mast cells were enzymatically dispersed from tonsil and skin tissues. The dis persed cells were then cultured with various stimuli, and tryptase and histamine levels in cell supernatants collected from challenge tubes were measured. Results:PAR-2 agonist peptide SLIGKV provoked a dose-dependent release of histamine from skin mast cells. It also induced tryptase release from tonsil mast cells, tcLIGRLO appeared less potent than SLIGKV in induction of release of histamine and tryptase. Trypsin was able to induce a "bell" shape increase in tryptase release from tonsil mast cells. It was also able to induce a dose-dependent release of histamine from both tonsil and skin mast cells. The actions of trypsin on mast cells were inhibited by soy bean trypsin inhibitor (SBTI) or α1-antitrypsin (α1-AT).Time course study revealed that both stimulated tryptase or histamine release initiated within 10 s and reached their peak release between 4 and 6 min. Pretreatment of cells with metabolic inhibitors or pertussis toxin reduced the ability of mast cells to release tryptase or histamine. Conclusion: It was demonstrated that the in vitro tryptase release properties of human tonsil and skin mast cells suggested a novel type of mast cell heterogeneity. The activation of mast cells by PAR-2 agonists indicated a self-amplification mechanism of mast cell degranulation.

  4. E17110 promotes reverse cholesterol transport with liver X receptor β agonist activity in vitro

    Directory of Open Access Journals (Sweden)

    Ni Li

    2016-05-01

    Full Text Available Liver X receptor (LXR plays an important role in reverse cholesterol transport (RCT, and activation of LXR could reduce atherosclerosis. In the present study we used a cell-based screening method to identify new potential LXRβ agonists. A novel benzofuran-2-carboxylate derivative was identified with LXRβ agonist activity: E17110 showed a significant activation effect on LXRβ with an EC50 value of 0.72 μmol/L. E17110 also increased the expression of ATP-binding cassette transporter A1 (ABCA1 and G1 (ABCG1 in RAW264.7 macrophages. Moreover, E17110 significantly reduced cellular lipid accumulation and promoted cholesterol efflux in RAW264.7 macrophages. Interestingly, we found that the key amino acids in the LXRβ ligand-binding domain had distinct interactions with E17110 as compared to TO901317. These results suggest that E17110 was identified as a novel compound with LXRβ agonist activity in vitro via screening, and could be developed as a potential anti-atherosclerotic lead compound.

  5. AAV vector-mediated overexpression of CB1 cannabinoid receptor in pyramidal neurons of the hippocampus protects against seizure-induced excitoxicity.

    Directory of Open Access Journals (Sweden)

    Stephan Guggenhuber

    Full Text Available The CB1 cannabinoid receptor is the most abundant G-protein coupled receptor in the brain and a key regulator of neuronal excitability. There is strong evidence that CB1 receptor on glutamatergic hippocampal neurons is beneficial to alleviate epileptiform seizures in mouse and man. Therefore, we hypothesized that experimentally increased CB1 gene dosage in principal neurons would have therapeutic effects in kainic acid (KA-induced hippocampal pathogenesis. Here, we show that virus-mediated conditional overexpression of CB1 receptor in pyramidal and mossy cells of the hippocampus is neuroprotective and moderates convulsions in the acute KA seizure model in mice. We introduce a recombinant adeno-associated virus (AAV genome with a short stop element flanked by loxP sites, for highly efficient attenuation of transgene expression on the transcriptional level. The presence of Cre-recombinase is strictly necessary for expression of reporter proteins or CB1 receptor in vitro and in vivo. Transgenic CB1 receptor immunoreactivity is targeted to glutamatergic neurons after stereotaxic delivery of AAV to the dorsal hippocampus of the driver mice NEX-cre. Increased CB1 receptor protein levels in hippocampal lysates of AAV-treated Cre-mice is paralleled by enhanced cannabinoid-induced G-protein activation. KA-induced seizure severity and mortality is reduced in CB1 receptor overexpressors compared with AAV-treated control animals. Neuronal damage in the hippocampal CA3 field is specifically absent from AAV-treated Cre-transgenics, but evident throughout cortical areas of both treatment groups. Our data provide further evidence for a role of increased CB1 signaling in pyramidal hippocampal neurons as a safeguard against the adverse effects of excessive excitatory network activity.

  6. Agonist properties of N,N-dimethyltryptamine at serotonin 5-HT2A and 5-HT2C receptors.

    Science.gov (United States)

    Smith, R L; Canton, H; Barrett, R J; Sanders-Bush, E

    1998-11-01

    Extensive behavioral and biochemical evidence suggests an agonist role at the 5-HT2A receptor, and perhaps the 5-HT2C receptor, in the mechanism of action of hallucinogenic drugs. However the published in vitro pharmacological properties of N,N-dimethyltryptamine (DMT), an hallucinogenic tryptamine analog, are not consistent with this hypothesis. We, therefore, undertook an extensive investigation into the properties of DMT at 5-HT2A and 5-HT2C receptors. In fibroblasts transfected with the 5-HT2A receptor or the 5-HT2C receptor, DMT activated the major intracellular signaling pathway (phosphoinositide hydrolysis) to an extent comparable to that produced by serotonin. Because drug efficacy changes with receptor density and cellular microenvironment, we also examined the properties of DMT in native preparations using a behavioral and biochemical approach. Rats were trained to discriminate an antagonist ketanserin from an agonist 1-(2,5-dimethoxy-4-iodophenyl)-2-aminopropane (DOI) in a two-lever choice paradigm. Pharmacological studies showed that responding on the DOI and ketanserin lever reflected agonist and antagonist activity at 5-HT2A receptors, and hence, was a suitable model for evaluating the in vivo functional properties of DMT. Like other 5-HT2A receptor agonists, DMT substituted fully for DOI. Intact choroid plexus was used to evaluate the agonist properties at endogenous 5-HT2C receptors; DMT was a partial agonist at 5-HT2C receptors in this native preparation. Thus, we conclude that DMT behaves as an agonist at both 5-HT2A and 5-HT2A receptors. One difference was evident in that the 5-HT2C, but not the 5-HT2A, receptor showed a profound desensitization to DMT over time. This difference is interesting in light of the recent report that the hallucinogenic activity of DMT does not tolerate in humans and suggests the 5-HT2C receptor plays a less prominent role in the action of DMT. PMID:9768567

  7. L-type channel inhibition by CB1 cannabinoid receptors is mediated by PTX-sensitive G proteins and cAMP/PKA in GT1-7 hypothalamic neurons.

    Science.gov (United States)

    Hoddah, Hanaa; Marcantoni, Andrea; Comunanza, Valentina; Carabelli, Valentina; Carbone, Emilio

    2009-01-01

    Using immortalized hypothalamic GT1-7 neurons, which express the CB1 cannabinoid receptor (CB1R) and three Ca2+ channel types (T, R and L), we found that the CB1R agonist WIN 55,212-2 inhibited the voltage-gated Ca2+ currents by about 35%. The inhibition by WIN 55,212-2 (10 microM) was reversible and prevented by nifedipine (3 microM), suggesting a selective action on L-type Ca2+ channels (LTCCs). WIN 55,212-2 action exhibited all the features of voltage-independent Ca2+ channel modulation: (1) no changes of the activation kinetics, (2) equal depressive action at all potentials and (3) no facilitation following strong prepulses. At variance with WIN 55,212-2, the CB1R inverse agonist AM-251 (10 microM) caused 20% increase of Ca2+ currents. The inhibition of LTCCs by WIN 55,212-2 was prevented by overnight PTX-incubation and by intracellular perfusion with GDP-beta-S. The latter caused also a 20% Ca2+ current up-regulation. WIN 55,212-2 action was also prevented by application of the PKA-blocker H89 or by loading the neurons with 8-CPT-cAMP. Our results suggest that LTCCs in GT1-7 neurons are partially inhibited at rest due to a constitutive CB1R activity removed by AM-251 and GDP-beta-S. Activation of CB1R via PTX-sensitive G proteins and cAMP/PKA pathway selectively depresses LTCCs that critically control the synchronized spontaneous firing and pulsatile release of gonadotropin-releasing hormone in GT1-7 neurons. PMID:19818494

  8. The effect of cannabinoids on dinitrofluorobenzene-induced experimental asthma in mice.

    Science.gov (United States)

    Bozkurt, Turgut Emrah; Kaya, Yesim; Durlu-Kandilci, Nezahat Tugba; Onder, Sevgen; Sahin-Erdemli, Inci

    2016-09-01

    Cannabinoids have anti-inflammatory effects and can produce bronchodilation in the airways. We have investigated the effects of cannabinoids on tracheal hyperreactivity and airway inflammation in dinitrofluorobenzene (DNFB)-induced experimental non-atopic asthma in mice. 5-hydroxytryptamine (5-HT)-induced contraction response was enhanced while carbachol- and electrical field stimulation-induced contractions, and isoprenaline-induced relaxation responses were remained unchanged in DNFB group. The increased 5-HT-induced contractions were inhibited by incubation with either atropine or tetrodotoxin. DNFB application resulted in increased macrophage number in the bronchoalveolar lavage fluid (BALF). In vivo ACEA (CB1 agonist) treatment prevented the increase in 5-HT contractions, while JWH133 (CB2 agonist) had no effect. However, neither ACEA nor JWH133 prevented the increase in macrophage number in BALF. In vitro ACEA incubation also inhibited the increase in 5-HT contraction in DNFB group. These results show that cannabinoid CB1 receptor agonist can prevent tracheal hyperreactivity to 5-HT in DNFB-induced non-atopic asthma in mice. PMID:27216000

  9. Mapping the effects of three dopamine agonists with different dyskinetogenic potential and receptor selectivity using pharmacological functional magnetic resonance imaging.

    Science.gov (United States)

    Delfino, Marina; Kalisch, Raffael; Czisch, Michael; Larramendy, Celia; Ricatti, Jimena; Taravini, Irene R E; Trenkwalder, Claudia; Murer, Mario Gustavo; Auer, Dorothee P; Gershanik, Oscar S

    2007-09-01

    The mechanisms underlying dopamine agonist-induced dyskinesia in Parkinson's disease remain poorly understood. Similar to patients, rats with severe nigrostriatal degeneration induced by 6-hydroxydopamine are more likely to show dyskinesia during chronic treatment with unselective dopamine receptor agonists than with D2 agonists, suggesting that D1 receptor stimulation alone or in conjunction with D2 receptor stimulation increases the chances of experiencing dyskinesia. As a first step towards disclosing drug-induced brain activation in dyskinesia, we examined the effects of dopamine agonists on behavior and blood oxygenation level-dependent (BOLD) signal in the striatum and motor cortex of rats with unilateral nigrostriatal lesions. Rats were rendered dyskinetic before pharmacologic functional magnetic resonance imaging by means of a repeated treatment regime with dopamine agonists. The unselective agonist apomorphine and the selective D1/D5 agonist SKF-81297 induced strong forelimb dyskinesia (FD) and axial dystonia and increased BOLD signal in the denervated striatum. Besides, SKF-81297 produced a significant but smaller BOLD increase in the intact striatum and a symmetric bilateral increase in the motor cortex. The D2 family agonist quinpirole, which induced mild dyskinesia on chronic treatment, did not produce BOLD changes in the striatum or motor cortex. Further evidence to support an association between BOLD changes and dyskinesia comes from a direct correlation between scores of FD and magnitude of drug-induced BOLD increases in the denervated striatum and motor cortex. Our results suggest that striatal and cortical activation induced by stimulation of D1/D5 receptors has a primary role in the induction of peak dose dyskinesia in parkinsonism. PMID:17287822

  10. Multiple functional therapeutic effects of the estrogen receptor β agonist indazole-Cl in a mouse model of multiple sclerosis

    OpenAIRE

    Moore, Spencer M.; Khalaj, Anna J.; Kumar, Shalini; Winchester, Zachary; Yoon, JaeHee; Yoo, Timothy; Martinez-Torres, Leonardo; Yasui, Norio; Katzenellenbogen, John A.; Tiwari-Woodruff, Seema Kaushalya

    2014-01-01

    In the search for effective multiple sclerosis treatment, much effort has been invested in estrogens and estrogen receptor (ER) agonists because of their neuroprotective benefits. However, because estrogens can produce ERα-based feminizing effects and cancer, ERβ agonists represent more desirable therapeutic candidates. The structurally unique ERβ ligand indazole chloride (Ind-Cl), a halogen-substituted phenyl-2H-indazole core, is a preclinical development candidate with a strong dossier. Our...

  11. Transcriptional Modulation of the Immune Response by Peroxisome Proliferator-Activated ReceptorAgonists in Autoimmune Disease1

    OpenAIRE

    Gocke, Anne R.; Hussain, Rehana Z.; Yang, Yuhong; Peng, Haiyan; Weiner, Jeffrey; Ben, Li-Hong; Drew, Paul D.; Stuve, Olaf; Lovett-Racke, Amy E.; Racke, Michael K.

    2009-01-01

    Peroxisome proliferator-activated receptor-α (PPARα) agonists have been shown to have a therapeutic benefit in experimental autoimmune encephalomyelitis (EAE), an animal model for multiple sclerosis (MS). In this study, we investigated the mechanism by which the PPARα agonist gemfibrozil induces immune deviation and protects mice from EAE. We demonstrated that treatment with gemfibrozil increases expression of the Th2 transcription factor GATA-3 and decreases expression of the Th1 transcripti...

  12. An update on PPAR activation by cannabinoids.

    Science.gov (United States)

    O'Sullivan, Saoirse Elizabeth

    2016-06-01

    Some cannabinoids activate the different isoforms of PPARs (α, β and γ), as shown through the use of reporter gene assays, binding studies, selective antagonists and knockout studies. Activation of all isoforms, but primarily PPARα and γ, mediates some (but not all) of the analgesic, neuroprotective, neuronal function modulation, anti-inflammatory, metabolic, anti-tumour, gastrointestinal and cardiovascular effects of some cannabinoids, often in conjunction with activation of the more traditional target sites of action such as the cannabinoid CB1 and CB2 receptors and the TRPV1 ion channel. PPARs also mediate some of the effects of inhibitors of endocannabinoid degradation or transport. Cannabinoids may be chaperoned to the PPARs by fatty acid binding proteins. The aims of this review are to update the evidence supporting PPAR activation by cannabinoids and to review the physiological responses to cannabinoids that are mediated, and not mediated, by PPAR activation. PMID:27077495

  13. Discovery of a potent and selective free fatty acid receptor 1 agonist with low lipophilicity and high oral bioavailability

    DEFF Research Database (Denmark)

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

    2013-01-01

    The free fatty acid receptor 1 (FFA1, also known as GPR40) mediates enhancement of glucose-stimulated insulin secretion and is emerging as a new target for the treatment of type 2 diabetes. Several FFA1 agonists are known, but the majority of these suffer from high lipophilicity. We have previously...... reported the FFA1 agonist 3 (TUG-424). We here describe the continued structure-activity exploration and optimization of this compound series, leading to the discovery of the more potent agonist 40, a compound with low lipophilicity, excellent in vitro metabolic stability and permeability, complete oral...

  14. Discovery of a potent and selective free fatty acid receptor 1 agonist with low lipophilicity and high oral bioavailability.

    Science.gov (United States)

    Christiansen, Elisabeth; Due-Hansen, Maria E; Urban, Christian; Grundmann, Manuel; Schmidt, Johannes; Hansen, Steffen V F; Hudson, Brian D; Zaibi, Mohamed; Markussen, Stine B; Hagesaether, Ellen; Milligan, Graeme; Cawthorne, Michael A; Kostenis, Evi; Kassack, Matthias U; Ulven, Trond

    2013-02-14

    The free fatty acid receptor 1 (FFA1, also known as GPR40) mediates enhancement of glucose-stimulated insulin secretion and is emerging as a new target for the treatment of type 2 diabetes. Several FFA1 agonists are known, but the majority of these suffer from high lipophilicity. We have previously reported the FFA1 agonist 3 (TUG-424). We here describe the continued structure-activity exploration and optimization of this compound series, leading to the discovery of the more potent agonist 40, a compound with low lipophilicity, excellent in vitro metabolic stability and permeability, complete oral bioavailability, and appreciable efficacy on glucose tolerance in mice. PMID:23294321

  15. Prediction of selective estrogen receptor beta agonist using open data and machine learning approach

    Science.gov (United States)

    Niu, Ai-qin; Xie, Liang-jun; Wang, Hui; Zhu, Bing; Wang, Sheng-qi

    2016-01-01

    Background Estrogen receptors (ERs) are nuclear transcription factors that are involved in the regulation of many complex physiological processes in humans. ERs have been validated as important drug targets for the treatment of various diseases, including breast cancer, ovarian cancer, osteoporosis, and cardiovascular disease. ERs have two subtypes, ER-α and ER-β. Emerging data suggest that the development of subtype-selective ligands that specifically target ER-β could be a more optimal approach to elicit beneficial estrogen-like activities and reduce side effects. Methods Herein, we focused on ER-β and developed its in silico quantitative structure-activity relationship models using machine learning (ML) methods. Results The chemical structures and ER-β bioactivity data were extracted from public chemogenomics databases. Four types of popular fingerprint generation methods including MACCS fingerprint, PubChem fingerprint, 2D atom pairs, and Chemistry Development Kit extended fingerprint were used as descriptors. Four ML methods including Naïve Bayesian classifier, k-nearest neighbor, random forest, and support vector machine were used to train the models. The range of classification accuracies was 77.10% to 88.34%, and the range of area under the ROC (receiver operating characteristic) curve values was 0.8151 to 0.9475, evaluated by the 5-fold cross-validation. Comparison analysis suggests that both the random forest and the support vector machine are superior for the classification of selective ER-β agonists. Chemistry Development Kit extended fingerprints and MACCS fingerprint performed better in structural representation between active and inactive agonists. Conclusion These results demonstrate that combining the fingerprint and ML approaches leads to robust ER-β agonist prediction models, which are potentially applicable to the identification of selective ER-β agonists. PMID:27486309

  16. Anti-radiation damage effect of polyethylenimine as a toll-like receptor 5 targeted agonist

    International Nuclear Information System (INIS)

    A number of agents are now available for use in protecting against ionizing radiation. These radiation-protective agents, however, have many adverse effects. Efforts have been made to develop new radiation-protective agents for medical application. Here, we investigated whether a compound, polyethylenimine (PEI), which activates Toll-like receptor 5 (TLR5)-mediated NF-kB signaling pathways, could have an anti-radiation effect on a mouse model. First, a cell-based screening model for an agonist of TLR5-mediated NF-kB pathway was established and then validated by activation of TLR5-mediated NF-kB luciferase reporter activity with a known TLR5 agonist, flagellin. We found that PEI induced dose-dependent activation of the TLR5-mediated NF-kB pathway, indicating that PEI is indeed a TLR5 agonist. Furthermore, the anti-radiation effect of polyethylenimine was assessed using a γ-ray total body irradiation (TBI) mouse model. Compared with the irradiation control, both survival time and survival rate were significantly improved in mice that received either a low dose of polyethylenimine (P=0.019) or a high dose of polyethylenimine (P<0.001). We also observed a positive correlation between animal body weight and survival time in mice that received a low dose of polyethylenimine, a high dose of polyethylenimine and amifostine, over a period of 30 days, r=0.42 (P<0.02), 0.72 (P<0.0001) and 0.95 (P<0.0001), respectively, while a negative correlation between animal body weight and survival time was observed in the irradiation control (r=-0.89; P<0.0001). These results indicate that polyethylenimine is a new TLR5 agonist with potential application in offering protection for patients receiving radiotherapy or in radiation-related accidents. (author)

  17. Combined Contribution of Endothelial Relaxing Autacoides in the Rat Femoral Artery Response to CPCA: An Adenosine A2 Receptor Agonist

    OpenAIRE

    Miroslav Radenković; Marko Stojanović; Radmila Janković; Mirko Topalović; Milica Stojiljković

    2012-01-01

    We examined the contribution of endothelial relaxing factors and potassium channels in actions of CPCA, potent adenosine A2 receptor agonist, on isolated intact male rat femoral artery (FA). CPCA produced concentration-dependent relaxation of FA, which was notably, but not completely, reduced after endothelial denudation. DPCPX, A1 receptor antagonist, had no significant effect, while SCH 58261 (A2A receptor antagonist) notably reduced CPCA-evoked effect. Pharmacological inhibition of nitric ...

  18. Adlea (ALGRX-4975), an injectable capsaicin (TRPV1 receptor agonist) formulation for longlasting pain relief.

    Science.gov (United States)

    Remadevi, Radhika; Szallisi, Arpad

    2008-02-01

    Anesiva Inc is developing Adlea (ALRGX-4975) - an injectable preparation of capsaicin, a TRPV1 (transient receptor potential vanilloid subfamily 1) receptor agonist - for the potential management of pain associated with osteoarthritis, tendonitiand postsurgical conditions, as well as for neuropathic pain occurring secondary to nerve injury. Adlea functions by desensitizing those neurons that conduct a long-lasting, throbbing form of pain. In phase II clinical trials, a single injection of Adlea significantly reduced pain levels in patients following total knee arthroplasty (TKA) or bunionectomy, and reduced pain in patients with osteoarthritis (OA) or Morton's neuroma. Phase II trials are ongoing to test Adlea in patients who are undergoing total hip arthroplasty or arthroscopic shoulder surgery and in patients with knee OA. Phase III clinical trials for the compound have been slated to begin in 2008 in patients following TKA or bunionectomy. Adlea appears to exhibit promise as a new medication in the treatment of conditions of chronic neuropathic pain. PMID:18240098

  19. Prediction of selective estrogen receptor beta agonist using open data and machine learning approach

    Directory of Open Access Journals (Sweden)

    Niu AQ

    2016-07-01

    for the classification of selective ER-β agonists. Chemistry Development Kit extended fingerprints and MACCS fingerprint performed better in structural representation between active and inactive agonists. Conclusion: These results demonstrate that combining the fingerprint and ML approaches leads to robust ER-β agonist prediction models, which are potentially applicable to the identification of selective ER-β agonists. Keywords: estrogen receptor subtype β, selective estrogen receptor modulators, quantitative structure-activity relationship models, machine learning approach

  20. Activation of type 1 cannabinoid receptor (CB1R promotes neurogenesis in murine subventricular zone cell cultures.

    Directory of Open Access Journals (Sweden)

    Sara Xapelli

    Full Text Available The endocannabinoid system has been implicated in the modulation of adult neurogenesis. Here, we describe the effect of type 1 cannabinoid receptor (CB1R activation on self-renewal, proliferation and neuronal differentiation in mouse neonatal subventricular zone (SVZ stem/progenitor cell cultures. Expression of CB1R was detected in SVZ-derived immature cells (Nestin-positive, neurons and astrocytes. Stimulation of the CB1R by (R-(+-Methanandamide (R-m-AEA increased self-renewal of SVZ cells, as assessed by counting the number of secondary neurospheres and the number of Sox2+/+ cell pairs, an effect blocked by Notch pathway inhibition. Moreover, R-m-AEA treatment for 48 h, increased proliferation as assessed by BrdU incorporation assay, an effect mediated by activation of MAPK-ERK and AKT pathways. Surprisingly, stimulation of CB1R by R-m-AEA also promoted neuronal differentiation (without affecting glial differentiation, at 7 days, as shown by counting the number of NeuN-positive neurons in the cultures. Moreover, by monitoring intracellular calcium concentrations ([Ca(2+]i in single cells following KCl and histamine stimuli, a method that allows the functional evaluation of neuronal differentiation, we observed an increase in neuronal-like cells. This proneurogenic effect was blocked when SVZ cells were co-incubated with R-m-AEA and the CB1R antagonist AM 251, for 7 days, thus indicating that this effect involves CB1R activation. In accordance with an effect on neuronal differentiation and maturation, R-m-AEA also increased neurite growth, as evaluated by quantifying and measuring the number of MAP2-positive processes. Taken together, these results demonstrate that CB1R activation induces proliferation, self-renewal and neuronal differentiation from mouse neonatal SVZ cell cultures.