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Sample records for endogenous cannabinoid receptor

  1. Endogenous cannabinoid receptor ligand induces the migration of human natural killer cells.

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    Kishimoto, Seishi; Muramatsu, Mayumi; Gokoh, Maiko; Oka, Saori; Waku, Keizo; Sugiura, Takayuki

    2005-02-01

    2-Arachidonoylglycerol is an endogenous ligand for the cannabinoid receptors (CB1 and CB2). Evidence is gradually accumulating which shows that 2-arachidonoylglycerol plays important physiological roles in several mammalian tissues and cells, yet the details remain ambiguous. In this study, we first examined the effects of 2-arachidonoylglycerol on the motility of human natural killer cells. We found that 2-arachidonoylglycerol induces the migration of KHYG-1 cells (a natural killer leukemia cell line) and human peripheral blood natural killer cells. The migration of natural killer cells induced by 2-arachidonoylglycerol was abolished by treating the cells with SR144528, a CB2 receptor antagonist, suggesting that the CB2 receptor is involved in the 2-arachidonoylglycerol-induced migration. In contrast to 2-arachidonoylglycerol, anandamide, another endogenous cannabinoid receptor ligand, did not induce the migration. Delta9-tetrahydrocannabinol, a major psychoactive constituent of marijuana, also failed to induce the migration; instead, the addition of delta9-tetrahydrocannabinol together with 2-arachidonoylglycerol abolished the migration induced by 2-arachidonoylglycerol. It is conceivable that the endogenous ligand for the cannabinoid receptor, that is, 2-arachidonoylglycerol, affects natural killer cell functions such as migration, thereby contributing to the host-defense mechanism against infectious viruses and tumor cells.

  2. Functional role of cannabinoid receptors in urinary bladder

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    Pradeep Tyagi

    2010-01-01

    Full Text Available Cannabinoids, the active components of Cannabis sativa (marijuana, 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 of cannabinoids on voiding dysfunction in multiple sclerosis patients. In this review, we shall summarize the literature on the expression of cannabinoid receptors in urinary bladder and the peripheral influence of locally and systemically administered cannabinoids in the bladder. The ongoing search for cannabinoid-based therapeutic strategies devoid of psychotropic effects can be complemented with local delivery into bladder by the intravesical route. A greater understanding of the role of the peripheral CB 1 and CB 2 receptor system in lower urinary tract is necessary to allow the development of new treatment for pelvic disorders.

  3. Computer modeling of Cannabinoid receptor type 1

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    Sapundzhi Fatima

    2018-01-01

    Full Text Available Cannabinoid receptors are important class of receptors as they are involved in various physiological processes such as appetite, pain-sensation, mood, and memory. It is important to design receptor-selective ligands in order to treat a particular disorder. The aim of the present study is to model the structure of cannabinoid receptor CB1 and to perform docking between obtained models and known ligands. Two models of CBR1 were prepared with two different methods (Modeller of Chimera and MOE. They were used for docking with GOLD 5.2. It was established a high correlation between inhibitory constant Ki of CB1 cannabinoid ligands and the ChemScore scoring function of GOLD, which concerns both models. This suggests that the models of the CB1 receptors obtained could be used for docking studies and in further investigation and design of new potential, selective and active cannabinoids with the desired effects.

  4. G-protein coupling of cannabinoid receptors

    International Nuclear Information System (INIS)

    Glass, M.

    2001-01-01

    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 [ 35 S]-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

  5. Endogenous cannabinoid release within prefrontal-limbic pathways affects memory consolidation of emotional training

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    Morena, M.; Roozendaal, B.; Trezza, V.; Ratano, P.; Peloso, A.; Hauer, D.; Atsak, P.; Trabace, L.; Cuomo, V.; McGaugh, J.L.; Schelling, G.; Campolongo, P.

    2014-01-01

    Previous studies have provided extensive evidence that administration of cannabinoid drugs after training modulates the consolidation of memory for an aversive experience. The present experiments investigated whether the memory consolidation is regulated by endogenously released cannabinoids. The

  6. Reducing cannabinoid abuse and preventing relapse by enhancing endogenous brain levels of kynurenic acid

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    Justinova, Zuzana; Mascia, Paola; Wu, Hui-Qiu; Secci, Maria E.; Redhi, Godfrey H.; Panlilio, Leigh V.; Scherma, Maria; Barnes, Chanel; Parashos, Alexandra; Zara, Tamara; Fratta, Walter; Solinas, Marcello; Pistis, Marco; Bergman, Jack; Kangas, Brian D.; Ferré, Sergi; Tanda, Gianluigi; Schwarcz, Robert; Goldberg, Steven R.

    2013-01-01

    In the reward circuitry of the brain, alpha-7-nicotinic acetylcholine receptors (α7nAChRs) modulate effects of delta-9-tetrahydrocannabinol (THC), marijuana’s main psychoactive ingredient. Kynurenic acid (KYNA) is an endogenous negative allosteric modulator of α7nAChRs. Here we report that the kynurenine 3-monooxygenase (KMO) inhibitor Ro 61-8048 increases brain KYNA levels and attenuates cannabinoid-induced increases in extracellular dopamine in reward-related brain areas. In the self-administration model of drug abuse, Ro 61-8048 reduced the rewarding effects of THC and the synthetic cannabinoid WIN 55,212-2 in squirrel monkeys and rats, respectively, and it also prevented relapse to drug-seeking induced by re-exposure to cannabinoids or cannabinoid-associated cues. The effects of enhancing endogenous KYNA levels with Ro 61-8048 were prevented by positive allosteric modulators of α7nAChRs. Despite a clear need, there are currently no medications approved for treatment of marijuana dependence. Modulation of KYNA provides a novel pharmacological strategy for achieving abstinence from marijuana and preventing relapse. PMID:24121737

  7. Rimonabant, a selective cannabinoid1 receptor antagonist, protects against light-induced retinal degeneration in vitro and in vivo.

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    Imamura, Tomoyo; Tsuruma, Kazuhiro; Inoue, Yuki; Otsuka, Tomohiro; Ohno, Yuta; Ogami, Shiho; Yamane, Shinsaku; Shimazawa, Masamitsu; Hara, Hideaki

    2017-05-15

    The endocannabinoid system is involved in some neurodegenerative diseases such as Alzheimer's disease. An endogenous constellation of proteins related to cannabinoid 1 receptor signaling, including free fatty acids, diacylglycerol lipase, and N-acylethanolamine-hydrolyzing acid amidase, are localized in the murine retina. Moreover, the expression levels of endogenous agonists of cannabinoid receptors are changed in the vitreous fluid. However, the role of the endocannabinoid system in the retina, particularly in the light-induced photoreceptor degeneration, remains unknown. Therefore, we investigated involvement of the cannabinoid 1 receptor in light-induced retinal degeneration using in vitro and in vivo models. To evaluate the effect of cannabinoid 1 receptors in light irradiation-induced cell death, the mouse retinal cone-cell line (661W) was treated with a cannabinoid 1 receptor antagonist, rimonabant. Time-dependent changes of expression and localization of retinal cannabinoid 1 receptors were measured using Western blot and immunostaining. Retinal damage was induced in mice by exposure to light, followed by intravitreal injection of rimonabant. Electroretinograms and histologic analyses were performed. Rimonabant suppressed light-induced photoreceptor cell death. Cannabinoid 1 receptor expression was upregulated by light exposure. Treatment with rimonabant improved both a- and b-wave amplitudes and the thickness of the outer nuclear layer. These results suggest that the cannabinoid 1 receptor is involved in light-induced retinal degeneration and it may represent a therapeutic target in the light-induced photoreceptor degeneration related diseases. Copyright © 2017 Elsevier B.V. All rights reserved.

  8. Multiple sleep alterations in mice lacking cannabinoid type 1 receptors.

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    Alessandro Silvani

    Full Text Available Cannabinoid type 1 (CB1 receptors are highly expressed in the brain and play a role in behavior control. Endogenous cannabinoid signaling is modulated by high-fat diet (HFD. We investigated the consequences of congenital lack of CB1 receptors on sleep in mice fed standard diet (SD and HFD. CB1 cannabinoid receptor knock-out (KO and wild-type (WT mice were fed SD or HFD for 4 months (n = 9-10 per group. Mice were instrumented with electroencephalographic (EEG and electromyographic electrodes. Recordings were performed during baseline (48 hours, sleep deprivation (gentle handling, 6 hours, sleep recovery (18 hours, and after cage switch (insomnia model paradigm, 6 hours. We found multiple significant effects of genotype on sleep. In particular, KO spent more time awake and less time in non-rapid-eye-movement sleep (NREMS and rapid-eye-movement sleep (REMS than WT during the dark (active period but not during the light (rest period, enhancing the day-night variation of wake-sleep amounts. KO had slower EEG theta rhythm during REMS. REMS homeostasis after sleep deprivation was less effective in KO than in WT. Finally, KO habituated more rapidly to the arousing effect of the cage-switch test than WT. We did not find any significant effects of diet or of diet x genotype interaction on sleep. The occurrence of multiple sleep alterations in KO indicates important roles of CB1 cannabinoid receptors in limiting arousal during the active period of the day, in sleep regulation, and in sleep EEG in mice.

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

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    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

  10. Functional interactions between endogenous cannabinoid and opioid systems: focus on alcohol, genetics and drug-addicted behaviors.

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    López-Moreno, J A; López-Jiménez, A; Gorriti, M A; de Fonseca, F Rodríguez

    2010-04-01

    Although the first studies regarding the endogenous opioid system and addiction were published during the 1940s, addiction and cannabinoids were not addressed until the 1970s. Currently, the number of opioid addiction studies indexed in PubMed-Medline is 16 times greater than the number of cannabinoid addiction reports. More recently, functional interactions have been demonstrated between the endogenous cannabinoid and opioid systems. For example, the cannabinoid brain receptor type 1 (CB1) and mu opioid receptor type 1 (MOR1) co-localize in the same presynaptic nerve terminals and signal through a common receptor-mediated G-protein pathway. Here, we review a great variety of behavioral models of drug addiction and alcohol-related behaviors. We also include data providing clear evidence that activation of the cannabinoid and opioid endogenous systems via WIN 55,512-2 (0.4-10 mg/kg) and morphine (1.0-10 mg/kg), respectively, produces similar levels of relapse to alcohol in operant alcohol self-administration tasks. Finally, we discuss genetic studies that reveal significant associations between polymorphisms in MOR1 and CB1 receptors and drug addiction. For example, the SNP A118G, which changes the amino acid aspartate to asparagine in the MOR1 gene, is highly associated with altered opioid system function. The presence of a microsatellite polymorphism of an (AAT)n triplet near the CB1 gene is associated with drug addiction phenotypes. But, studies exploring haplotypes with regard to both systems, however, are lacking.

  11. R-Flurbiprofen Reduces Neuropathic Pain in Rodents by Restoring Endogenous Cannabinoids

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    Marian, Claudiu; Häussler, Annett; Wijnvoord, Nina; Ziebell, Simone; Metzner, Julia; Koch, Marco; Myrczek, Thekla; Bechmann, Ingo; Kuner, Rohini; Costigan, Michael; Dehghani, Faramarz; Geisslinger, Gerd; Tegeder, Irmgard

    2010-01-01

    Background R-flurbiprofen, one of the enantiomers of flurbiprofen racemate, is inactive with respect to cyclooxygenase inhibition, but shows analgesic properties without relevant toxicity. Its mode of action is still unclear. Methodology/Principal Findings We show that R-flurbiprofen reduces glutamate release in the dorsal horn of the spinal cord evoked by sciatic nerve injury and thereby alleviates pain in sciatic nerve injury models of neuropathic pain in rats and mice. This is mediated by restoring the balance of endocannabinoids (eCB), which is disturbed following peripheral nerve injury in the DRGs, spinal cord and forebrain. The imbalance results from transcriptional adaptations of fatty acid amide hydrolase (FAAH) and NAPE-phospholipase D, i.e. the major enzymes involved in anandamide metabolism and synthesis, respectively. R-flurbiprofen inhibits FAAH activity and normalizes NAPE-PLD expression. As a consequence, R-Flurbiprofen improves endogenous cannabinoid mediated effects, indicated by the reduction of glutamate release, increased activity of the anti-inflammatory transcription factor PPARγ and attenuation of microglia activation. Antinociceptive effects are lost by combined inhibition of CB1 and CB2 receptors and partially abolished in CB1 receptor deficient mice. R-flurbiprofen does however not cause changes of core body temperature which is a typical indicator of central effects of cannabinoid-1 receptor agonists. Conclusion Our results suggest that R-flurbiprofen improves the endogenous mechanisms to regain stability after axonal injury and to fend off chronic neuropathic pain by modulating the endocannabinoid system and thus constitutes an attractive, novel therapeutic agent in the treatment of chronic, intractable pain. PMID:20498712

  12. R-flurbiprofen reduces neuropathic pain in rodents by restoring endogenous cannabinoids.

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    Philipp Bishay

    Full Text Available BACKGROUND: R-flurbiprofen, one of the enantiomers of flurbiprofen racemate, is inactive with respect to cyclooxygenase inhibition, but shows analgesic properties without relevant toxicity. Its mode of action is still unclear. METHODOLOGY/PRINCIPAL FINDINGS: We show that R-flurbiprofen reduces glutamate release in the dorsal horn of the spinal cord evoked by sciatic nerve injury and thereby alleviates pain in sciatic nerve injury models of neuropathic pain in rats and mice. This is mediated by restoring the balance of endocannabinoids (eCB, which is disturbed following peripheral nerve injury in the DRGs, spinal cord and forebrain. The imbalance results from transcriptional adaptations of fatty acid amide hydrolase (FAAH and NAPE-phospholipase D, i.e. the major enzymes involved in anandamide metabolism and synthesis, respectively. R-flurbiprofen inhibits FAAH activity and normalizes NAPE-PLD expression. As a consequence, R-Flurbiprofen improves endogenous cannabinoid mediated effects, indicated by the reduction of glutamate release, increased activity of the anti-inflammatory transcription factor PPARgamma and attenuation of microglia activation. Antinociceptive effects are lost by combined inhibition of CB1 and CB2 receptors and partially abolished in CB1 receptor deficient mice. R-flurbiprofen does however not cause changes of core body temperature which is a typical indicator of central effects of cannabinoid-1 receptor agonists. CONCLUSION: Our results suggest that R-flurbiprofen improves the endogenous mechanisms to regain stability after axonal injury and to fend off chronic neuropathic pain by modulating the endocannabinoid system and thus constitutes an attractive, novel therapeutic agent in the treatment of chronic, intractable pain.

  13. Multiple sclerosis following treatment with a cannabinoid receptor-1 antagonist

    NARCIS (Netherlands)

    van Oosten, B. W.; Killestein, J.; Mathus-Vliegen, E. M. H.; Polman, C. H.

    2004-01-01

    Laboratory research including animal models of human disease suggests that cannabinoids might have therapeutic potential in multiple sclerosis (MS). We have recently seen a 46-year-old woman who developed MS after starting treatment with a cannabinoid receptor antagonist for obesity. The occurrence

  14. The future of type 1 cannabinoid receptor allosteric ligands.

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    Alaverdashvili, Mariam; Laprairie, Robert B

    2018-02-01

    Allosteric modulation of the type 1 cannabinoid receptor (CB1R) holds great therapeutic potential. This is because allosteric modulators do not possess intrinsic efficacy, but instead augment (positive allosteric modulation) or diminish (negative allosteric modulation) the receptor's response to endogenous ligand. Consequently, CB1R allosteric modulators have an effect ceiling which allows for the tempering of CB1R signaling without the desensitization, tolerance, dependence, and psychoactivity associated with orthosteric compounds. Pain, movement disorders, epilepsy, obesity are all potential therapeutic targets for CB1R allosteric modulation. Several challenges exist for the development of CB1R allosteric modulators, such as receptor subtype specificity, translation to in vivo systems, and mixed allosteric/agonist/inverse agonist activity. Despite these challenges, elucidation of crystal structures of CB1R and compound design based on structure-activity relationships will advance the field. In this review, we will cover recent progress for CB1R allosteric modulators and discuss the future promise of this research.

  15. Leptin Receptor Deficiency is Associated With Upregulation of Cannabinoid 1 Receptors in Limbic Brain Regions

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    THANOS, PANAYOTIS K.; RAMALHETE, ROBERTO C.; MICHAELIDES, MICHAEL; PIYIS, YIANNI K.; WANG, GENE-JACK; VOLKOW, NORA D.

    2009-01-01

    Leptin receptor dysfunction results in overeating and obesity. Leptin regulates hypothalamic signaling that underlies the motivation to hyperphagia, but the interaction between leptin and cannabinoid signaling is poorly understood. We evaluated the role of cannabinoid 1 receptors (CB1R) in overeating and the effects of food deprivation on CB1R in the brain. One-month-old Zucker rats were divided into unrestricted and restricted (fed 70% of unrestricted rats) diet groups and maintained until adulthood (4 months). Levels of relative binding sites of CB1R (CB1R binding levels) were assessed using [3H] SR141716A in vitro autoradiography. These levels were higher (except cerebellum and hypothalamus) at 4 months than at 1 month of age. One month CB1R binding levels for most brain regions did not differ between Ob and Lean (Le) rats (except in frontal and cingulate cortices in Le and in the hypothalamus in Ob). Four month Ob rats had higher CB1R binding levels than Le in most brain regions and food restriction was associated with higher CB1R levels in all brain regions in Ob, but not in Le rats. CB1R binding levels increased between adolescence and young adulthood which we believe was influenced by leptin and food availability. The high levels of CB1R in Ob rats suggest that leptin's inhibition of food-intake is in part mediated by downregulation of CB1R and that leptin interferes with CB1R upregulation under food-deprivation conditions. These results are consistent with prior findings showing increased levels of endogenous cannabinoids in the Ob rats corroborating the regulation of cannabinoid signaling by leptin. PMID:18563836

  16. Endogenous and Synthetic Cannabinoids as Therapeutics in Retinal Disease

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    Despina Kokona

    2016-01-01

    Full Text Available The functional significance of cannabinoids in ocular physiology and disease has been reported some decades ago. In the early 1970s, subjects who smoked Cannabis sativa developed lower intraocular pressure (IOP. This led to the isolation of phytocannabinoids from this plant and the study of their therapeutic effects in glaucoma. The main treatment of this disease to date involves the administration of drugs mediating either the decrease of aqueous humour synthesis or the increase of its outflow and thus reduces IOP. However, the reduction of IOP is not sufficient to prevent visual field loss. Retinal diseases, such as glaucoma and diabetic retinopathy, have been defined as neurodegenerative diseases and characterized by ischemia-induced excitotoxicity and loss of retinal neurons. Therefore, new therapeutic strategies must be applied in order to target retinal cell death, reduction of visual acuity, and blindness. The aim of the present review is to address the neuroprotective and therapeutic potential of cannabinoids in retinal disease.

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

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    Arnau Busquets Garcia

    2016-05-01

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

  18. Glycine receptors in CNS neurons as a target for nonretrograde action of cannabinoids

    NARCIS (Netherlands)

    Lozovaya, N.; Yatsenko, N.; Beketov, A.; Tsintsadze, T.; Burnashev, N.

    2005-01-01

    At many central synapses, endocannabinoids released by postsynaptic cells act retrogradely on presynaptic G-protein-coupled cannabinoid receptors to inhibit neurotransmitter release. Here, we demonstrate that cannabinoids may directly affect the functioning of inhibitory glycine receptor (GlyR)

  19. Cannabinoids on the Brain

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    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.

  20. Endogenous Receptor Agonists: Resolving Inflammation

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    Gerhard Bannenberg

    2007-01-01

    Full Text Available Controlled resolution or the physiologic resolution of a well-orchestrated inflammatory response at the tissue level is essential to return to homeostasis. A comprehensive understanding of the cellular and molecular events that control the termination of acute inflammation is needed in molecular terms given the widely held view that aberrant inflammation underlies many common diseases. This review focuses on recent advances in the understanding of the role of arachidonic acid and ω-3 polyunsaturated fatty acids (PUFA–derived lipid mediators in regulating the resolution of inflammation. Using a functional lipidomic approach employing LC-MS-MS–based informatics, recent studies, reviewed herein, uncovered new families of local-acting chemical mediators actively biosynthesized during the resolution phase from the essential fatty acids eicosapentaenoic acid (EPA and docosahexaenoic acid (DHA. These new families of local chemical mediators are generated endogenously in exudates collected during the resolution phase, and were coined resolvins and protectins because specific members of these novel chemical families control both the duration and magnitude of inflammation in animal models of complex diseases. Recent advances on the biosynthesis, receptors, and actions of these novel anti-inflammatory and proresolving lipid mediators are reviewed with the aim to bring to attention the important role of specific lipid mediators as endogenous agonists in inflammation resolution.

  1. Cannabinoids and Pain

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    J Michael Walker

    2001-01-01

    Full Text Available Cannabinoids have been used to treat pain for many centuries. However, only during the past several decades have rigorous scientific methods been applied to understand the mechanisms of cannabinoid action. Cannabinoid receptors were discovered in the late 1980s and have been found to mediate the effects of cannabinoids on the nervous system. Several endocannabinoids were subsequently identified. Many studies of cannabinoid analgesia in animals during the past century showed that cannabinoids block all types of pain studied. These effects were found to be due to the suppression of spinal and thalamic nociceptive neurons, independent of any actions on the motor systems. Spinal, supraspinal and peripheral sites of cannabinoid analgesia have been identified. Endocannabinoids are released upon electrical stimulation of the periaqueductal gray, and in response to inflammation in the extremities. These observations and others thus suggest that a natural function of cannabinoid receptors and their endogenous ligands is to regulate pain sensitivity. The therapeutic potential of cannabinoids remains an important topic for future investigations, with previous work suggesting utility in clinical studies of cancer and surgical pain. New modes of delivery and/or new compounds lacking the psychotropic properties of the standard cannabinoid ligands offer promise for cannabinoid therapeutics for pain.

  2. Cannabinoid Receptors: A Novel Target for Therapy for Prostate Cancer

    National Research Council Canada - National Science Library

    Mukhtar, Hasan; Afaq, Farrukh; Sarfaraz, Sami

    2008-01-01

    We have shown that the expression levels of both cannabinoid receptors CB1 and CB2 are higher in human prostate cancer cells than in normal prostate epithelial cells and treatment of LNCaP cells with WIN-55,212-2 (WIN...

  3. Cannabinoid Receptors: A Novel Target for Treating Prostate Cancer

    National Research Council Canada - National Science Library

    Mukhtar, Hasan; Afaq, Farrukh; Sarfaraz, Sami

    2006-01-01

    Recently we have shown that expression levels of both cannabinoid receptors CB and CB12 are higher in human prostate cancer cells than in normal prostate epithelial cells and treatment of LNCaP cells with WIN-55,212-2...

  4. Cannabinoid Receptors: A Novel Target for Therapy of Prostate Cancer

    National Research Council Canada - National Science Library

    Mukhtar, Hasan; Afaq, Farrukh; Sarfaraz, Sami

    2007-01-01

    .... We have shown that the expression levels of both cannabinoid receptors CB1 and CB2 are higher in human prostate cancer cells than in normal prostate epithelial cells and treatment of LNCaP cells with WIN-55,212-2 (WIN...

  5. Cannabinoid Receptors: A Novel Target for Therapy of Prostate Cancer

    National Research Council Canada - National Science Library

    Mukhtar, Hasan; Afaq, Farrukh; Sarfaraz, Sami

    2005-01-01

    .... Here we show that expression levels of both cannabinoid receptors CB(sub 1) and CB(sub 2) are significantly higher in CA-HPV-10 and other human prostate cells LNCaP, DUI45, PC3, and CWR22RV1 than in human prostate epithelial and PZ-HPV-7 cells...

  6. The Cannabinoid Receptor CB1 Modulates the Signaling Properties of the Lysophosphatidylinositol Receptor GPR55*

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    Kargl, Julia; Balenga, Nariman; Parzmair, Gerald P.; Brown, Andrew J.; Heinemann, Akos; Waldhoer, Maria

    2012-01-01

    The G protein-coupled receptor (GPCR) 55 (GPR55) and the cannabinoid receptor 1 (CB1R) are co-expressed in many tissues, predominantly in the central nervous system. Seven transmembrane spanning (7TM) receptors/GPCRs can form homo- and heteromers and initiate distinct signaling pathways. Recently, several synthetic CB1 receptor inverse agonists/antagonists, such as SR141716A, AM251, and AM281, were reported to activate GPR55. Of these, SR141716A was marketed as a promising anti-obesity drug, but was withdrawn from the market because of severe side effects. Here, we tested whether GPR55 and CB1 receptors are capable of (i) forming heteromers and (ii) whether such heteromers could exhibit novel signaling patterns. We show that GPR55 and CB1 receptors alter each others signaling properties in human embryonic kidney (HEK293) cells. We demonstrate that the co-expression of FLAG-CB1 receptors in cells stably expressing HA-GPR55 specifically inhibits GPR55-mediated transcription factor activation, such as nuclear factor of activated T-cells and serum response element, as well as extracellular signal-regulated kinases (ERK1/2) activation. GPR55 and CB1 receptors can form heteromers, but the internalization of both receptors is not affected. In addition, we observe that the presence of GPR55 enhances CB1R-mediated ERK1/2 and nuclear factor of activated T-cell activation. Our data provide the first evidence that GPR55 can form heteromers with another 7TM/GPCR and that this interaction with the CB1 receptor has functional consequences in vitro. The GPR55-CB1R heteromer may play an important physiological and/or pathophysiological role in tissues endogenously co-expressing both receptors. PMID:23161546

  7. Expression and function of cannabinoid receptors CB1 and CB2 and their cognate cannabinoid ligands in murine embryonic stem cells.

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    Shuxian Jiang

    2007-07-01

    Full Text Available Characterization of intrinsic and extrinsic factors regulating the self-renewal/division and differentiation of stem cells is crucial in determining embryonic stem (ES cell fate. ES cells differentiate into multiple hematopoietic lineages during embryoid body (EB formation in vitro, which provides an experimental platform to define the molecular mechanisms controlling germ layer fate determination and tissue formation.The cannabinoid receptor type 1 (CB1 and cannabinoid receptor type 2 (CB2 are members of the G-protein coupled receptor (GPCR family, that are activated by endogenous ligands, the endocannabinoids. CB1 receptor expression is abundant in brain while CB2 receptors are mostly expressed in hematopoietic cells. However, the expression and the precise roles of CB1 and CB2 and their cognate ligands in ES cells are not known. We observed significant induction of CB1 and CB2 cannabinoid receptors during the hematopoietic differentiation of murine ES (mES-derived embryoid bodies. Furthermore, mES cells as well as ES-derived embryoid bodies at days 7 and 14, expressed endocannabinoids, the ligands for both CB1 and CB2. The CB1 and CB2 antagonists (AM251 and AM630, respectively induced mES cell death, strongly suggesting that endocannabinoids are involved in the survival of mES cells. Treatment of mES cells with the exogenous cannabinoid ligand Delta(9-THC resulted in the increased hematopoietic differentiation of mES cells, while addition of AM251 or AM630 blocked embryoid body formation derived from the mES cells. In addition, cannabinoid agonists induced the chemotaxis of ES-derived embryoid bodies, which was specifically inhibited by the CB1 and CB2 antagonists.This work has not been addressed previously and yields new information on the function of cannabinoid receptors, CB1 and CB2, as components of a novel pathway regulating murine ES cell differentiation. This study provides insights into cannabinoid system involvement in ES cell

  8. Innovative Therapeutic Potential of Cannabinoid Receptors as Targets in Alzheimer's disease and Less Well-Known Diseases.

    Science.gov (United States)

    Paez, Juan A; Campillo, Nuria E

    2018-02-25

    The discovery of cannabinoid receptors at the beginning of the 1990s, CB1 being cloned in 1990 and CB2 cloned in 1993, and the availability of selective and potent cannabimimetics could only be justified by the existence of endogenous ligands that are capable of binding to them. Thus, the characterisation and cloning of the first cannabinoid receptor (CB1) led to the isolation and characterisation of the first endocannabinoid, arachidonoylethanolamide (AEA), two years later and the subsequent identification of a family of lipid transmitters known as the fatty acid ester 2-arachidonoylglycerol (2-AG). The endogenous cannabinoid system is a complex signalling system that comprises transmembrane endocannabinoid receptors, their endogenous ligands (the endocannabinoids), the specific uptake mechanisms and the enzymatic systems related to their biosynthesis and degradation. The endocannabinoid system has been implicated in a wide diversity of biological processes, in both the central and peripheral nervous systems, including memory, learning, neuronal development, stress and emotions, food intake, energy regulation, peripheral metabolism, and the regulation of hormonal balance through the endocrine system. In this context, this article will review the current knowledge of the therapeutic potential of cannabinoid receptor as a target in Alzheimer's disease and other less well-known diseases that include, among others, multiple sclerosis, bone metabolism, and Fragile X syndrome. The therapeutic applications will be addressed through the study of cannabinoid agonists acting as single drugs and multi-target drugs highlighting the CB2 receptor agonist. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

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

    DEFF Research Database (Denmark)

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

    2014-01-01

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

  10. Genetic variability in the human cannabinoid receptor 1 is associated with resting state EEG theta power in humans.

    Science.gov (United States)

    Heitland, I; Kenemans, J L; Böcker, K B E; Baas, J M P

    2014-11-01

    It has long been postulated that exogenous cannabinoids have a profound effect on human cognitive functioning. These cannabinoid effects are thought to depend, at least in parts, on alterations of phase-locking of local field potential neuronal firing. The latter can be measured as activity in the theta frequency band (4-7Hz) by electroencephalogram. Theta oscillations are supposed to serve as a mechanism in neural representations of behaviorally relevant information. However, it remains unknown whether variability in endogenous cannabinoid activity is involved in theta rhythms and therefore, may serve as an individual differences index of human cognitive functioning. To clarify this issue, we recorded resting state EEG activity in 164 healthy human subjects and extracted EEG power across frequency bands (δ, θ, α, and β). To assess variability in the endocannabinoid system, two genetic polymorphisms (rs1049353, rs2180619) within the cannabinoid receptor 1 (CB1) were determined in all participants. As expected, we observed significant effects of rs1049353 on EEG power in the theta band at frontal, central and parietal electrode regions. Crucially, these effects were specific for the theta band, with no effects on activity in the other frequency bands. Rs2180619 showed no significant associations with theta power after Bonferroni correction. Taken together, we provide novel evidence in humans showing that genetic variability in the cannabinoid receptor 1 is associated with resting state EEG power in the theta frequency band. This extends prior findings of exogenous cannabinoid effects on theta power to the endogenous cannabinoid system. Copyright © 2014 Elsevier B.V. All rights reserved.

  11. 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.

  12. Characterization of the hypothermic effect of the synthetic cannabinoid HU-210 in the rat. Relation to the adrenergic system and endogenous pyrogens.

    Science.gov (United States)

    Ovadia, H; Wohlman, A; Mechoulam, R; Weidenfeld, J

    1995-02-01

    In the present study we have characterized the hypothermic effect of the psychoactive cannabinoid HU-210, by investigating its interaction with the endogenous pyrogens, IL-1 and PGE2. We also studied the involvement of the adrenergic system in mediation of this hypothermic effect. Injection of HU-210 directly into the preoptic area caused a dose dependent reduction of rectal temperature from 37 to 32.1 degrees C. Injection of the non-psychoactive analog, HU-211 which does not bind to brain cannabinoid receptor, did not affect body temperature. Injection of the adrenergic agonists, CGP-12177 and clonidine (beta, and alpha adrenergic agonists, respectively) abrogated the hypothermia induced by HU-210. Injection of the adrenergic antagonists, prazosin (alpha 1) and propranolol (beta) enhanced the hypothermic effect of HU-210. Intracerebral administration of IL-1 or PGE2 to rats pretreated with HU-210 caused a transient inhibition of the hypothermia. The ex vivo rate of basal or bacterial endotoxin-induced synthesis of PGE2 by different brain regions, including the preoptic area was not affected by HU-210 administration. These results suggest that the synthetic cannabinoid HU-210 acts in the preoptic area, probably via the brain cannabinoid receptor to induce hypothermia. The hypothermic effect can be antagonized by adrenergic agonists and enhanced by adrenergic antagonists. HU-210 does not interfere with the pyrogenic effect of IL-1 or PGE2.

  13. Reversible and regionally selective downregulation of brain cannabinoid CB1 receptors in chronic daily cannabis smokers

    OpenAIRE

    Hirvonen, J; Goodwin, RS; Li, C-T; Terry, GE; Zoghbi, SS; Morse, C; Pike, VW; Volkow, ND; Huestis, MA; Innis, RB

    2011-01-01

    Chronic cannabis (marijuana, hashish) smoking can result in dependence. Rodent studies show reversible downregulation of brain cannabinoid CB1 (cannabinoid receptor type 1) receptors after chronic exposure to cannabis. However, whether downregulation occurs in humans who chronically smoke cannabis is unknown. Here we show, using positron emission tomography imaging, reversible and regionally selective downregulation of brain cannabinoid CB1 receptors in human subjects who chronically smoke ca...

  14. Opportunistic activation of TRP receptors by endogenous lipids: exploiting lipidomics to understand TRP receptor cellular communication.

    Science.gov (United States)

    Bradshaw, Heather B; Raboune, Siham; Hollis, Jennifer L

    2013-03-19

    Transient receptor potential channels (TRPs) form a large family of ubiquitous non-selective cation channels that function as cellular sensors and in many cases regulate intracellular calcium. Identification of the endogenous ligands that activate these TRP receptors is still under intense investigation with the majority of these channels still remaining "orphans." That these channels respond to a variety of external stimuli (e.g. plant-derived lipids, changes in temperature, and changes in pH) provides a framework for their abilities as cellular sensors, however, the mechanism of direct activation is still under much debate and research. In the cases where endogenous ligands (predominately lipids) have shown direct activation of a channel, multiple ligands have been shown to activate the same channel suggesting that these receptors are "promiscuous" in nature. Lipidomics of a growing class of endogenous lipids, N-acyl amides, the most famous of which is N-arachidonoyl ethanolamine (the endogenous cannabinoid, Anandamide) is providing a novel set of ligands that have been shown to activate some members of the TRP family and have the potential to deorphanize many more. Here it is argued that activation of TRPV receptors, a subset of the larger family of TRPs, by multiple endogenous lipids that are structurally analogous is a model system to drive our understanding that many TRP receptors are not promiscuous, but are more characteristically "opportunistic" in nature; exploiting the structural similarity and biosynthesis of a narrow range of analogous endogenous lipids. In addition, this manuscript will compare the activation properties of TRPC5 to the activity profile of an "orphan" lipid, N-palmitoyl glycine; further demonstrating that lipidomics aimed at expanding our knowledge of the family of N-acyl amides has the potential to provide novel avenues of research for TRP receptors. Copyright © 2012 Elsevier Inc. All rights reserved.

  15. 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.

  16. 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)

    Tomiyama, Ken-ichi; Funada, Masahiko

    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 1 receptor antagonist AM251, but not with the selective CB 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 1 receptor, but not by the CB 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 1 receptor, but not by the CB 2 receptor, and involves caspase-dependent apoptosis. • A high concentration of synthetic cannabinoids may be toxic to neuronal cells that express CB 1 receptors

  17. Cannabinoid receptor CB2 modulates axon guidance

    DEFF Research Database (Denmark)

    Duff, Gabriel; Argaw, Anteneh; Cecyre, Bruno

    2013-01-01

    on axon guidance. These effects are specific to CB2R since no changes were observed in mice where the gene coding for this receptor was altered (cnr2 (-/-)). The CB2R induced morphological changes observed at the growth cone are PKA dependent and require the presence of the netrin-1 receptor, Deleted...... CB2R's implication in retinothalamic development. Overall, this study demonstrates that the contribution of endocannabinoids to brain development is not solely mediated by CB1R, but also involves CB2R....

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

    Directory of Open Access Journals (Sweden)

    Janaína P. Jaeger

    2008-01-01

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

  19. Reversible and regionally selective downregulation of brain cannabinoid CB1 receptors in chronic daily cannabis smokers.

    Science.gov (United States)

    Hirvonen, J; Goodwin, R S; Li, C-T; Terry, G E; Zoghbi, S S; Morse, C; Pike, V W; Volkow, N D; Huestis, M A; Innis, R B

    2012-06-01

    Chronic cannabis (marijuana, hashish) smoking can result in dependence. Rodent studies show reversible downregulation of brain cannabinoid CB(1) (cannabinoid receptor type 1) receptors after chronic exposure to cannabis. However, whether downregulation occurs in humans who chronically smoke cannabis is unknown. Here we show, using positron emission tomography imaging, reversible and regionally selective downregulation of brain cannabinoid CB(1) receptors in human subjects who chronically smoke cannabis. Downregulation correlated with years of cannabis smoking and was selective to cortical brain regions. After ∼4 weeks of continuously monitored abstinence from cannabis on a secure research unit, CB(1) receptor density returned to normal levels. This is the first direct demonstration of cortical cannabinoid CB(1) receptor downregulation as a neuroadaptation that may promote cannabis dependence in human brain.

  20. Reinforcing and neurochemical effects of cannabinoid CB1 receptor agonists, but not cocaine, are altered by an adenosine A2A receptor antagonist.

    Science.gov (United States)

    Justinová, Zuzana; Ferré, Sergi; Redhi, Godfrey H; Mascia, Paola; Stroik, Jessica; Quarta, Davide; Yasar, Sevil; Müller, Christa E; Franco, Rafael; Goldberg, Steven R

    2011-07-01

    Several recent studies suggest functional and molecular interactions between striatal adenosine A(2A) and cannabinoid CB(1) receptors. Here, we demonstrate that A(2A) receptors selectively modulate reinforcing effects of cannabinoids. We studied effects of A(2A) receptor blockade on the reinforcing effects of delta-9-tetrahydrocannabinol (THC) and the endogenous CB(1) receptor ligand anandamide under a fixed-ratio schedule of intravenous drug injection in squirrel monkeys. A low dose of the selective adenosine A(2A) receptor antagonist MSX-3 (1 mg/kg) caused downward shifts of THC and anandamide dose-response curves. In contrast, a higher dose of MSX-3 (3 mg/kg) shifted THC and anandamide dose-response curves to the left. MSX-3 did not modify cocaine or food pellet self-administration. Also, MSX-3 neither promoted reinstatement of extinguished drug-seeking behavior nor altered reinstatement of drug-seeking behavior by non-contingent priming injections of THC. Finally, using in vivo microdialysis in freely-moving rats, a behaviorally active dose of MSX-3 significantly counteracted THC-induced, but not cocaine-induced, increases in extracellular dopamine levels in the nucleus accumbens shell. The significant and selective results obtained with the lower dose of MSX-3 suggest that adenosine A(2A) antagonists acting preferentially at presynaptic A(2A) receptors might selectively reduce reinforcing effects of cannabinoids that lead to their abuse. However, the appearance of potentiating rather than suppressing effects on cannabinoid reinforcement at the higher dose of MSX-3 would likely preclude the use of such a compound as a medication for cannabis abuse. Adenosine A(2A) antagonists with more selectivity for presynaptic versus postsynaptic receptors could be potential medications for treatment of cannabis abuse. Addiction Biology © 2010 Society for the Study of Addiction. No claim to original US government works.

  1. Cannabinoid Receptors and the Endocannabinoid System: Signaling and Function in the Central Nervous System

    Directory of Open Access Journals (Sweden)

    Shenglong Zou

    2018-03-01

    Full Text Available The biological effects of cannabinoids, the major constituents of the ancient medicinal plant Cannabis sativa (marijuana are mediated by two members of the G-protein coupled receptor family, cannabinoid receptors 1 (CB1R and 2. The CB1R is the prominent subtype in the central nervous system (CNS and has drawn great attention as a potential therapeutic avenue in several pathological conditions, including neuropsychological disorders and neurodegenerative diseases. Furthermore, cannabinoids also modulate signal transduction pathways and exert profound effects at peripheral sites. Although cannabinoids have therapeutic potential, their psychoactive effects have largely limited their use in clinical practice. In this review, we briefly summarized our knowledge of cannabinoids and the endocannabinoid system, focusing on the CB1R and the CNS, with emphasis on recent breakthroughs in the field. We aim to define several potential roles of cannabinoid receptors in the modulation of signaling pathways and in association with several pathophysiological conditions. We believe that the therapeutic significance of cannabinoids is masked by the adverse effects and here alternative strategies are discussed to take therapeutic advantage of cannabinoids.

  2. Synthetic Cannabinoids

    Directory of Open Access Journals (Sweden)

    Aslihan Okan Ibiloglu

    2017-09-01

    Full Text Available Synthetic cannabinoids which is a subgroup of cannabinoids are commonly used for recreational drug use throughout the whole world. Although both marijuana and synthetic cannabinoids stimulate the same receptors, cannabinoid receptor 1 (CB1 and cannabinoid receptor 2 (CB2, studies have shown that synthetic cannabinoids are much more potent than marijuana. The longer use of synthetic cannabinoids can cause severe physical and psychological symptoms that might even result in death, similar to many known illicit drugs. Main treatment options mostly involve symptom management and supportive care. The aim of this article is to discuss clinical and pharmacological properties of the increasingly used synthetic cannabinoids. [Psikiyatride Guncel Yaklasimlar - Current Approaches in Psychiatry 2017; 9(3.000: 317-328

  3. Cannabinoids Modulate Neuronal Activity and Cancer by CB1 and CB2 Receptor-Independent Mechanisms

    Directory of Open Access Journals (Sweden)

    Ken Soderstrom

    2017-10-01

    Full Text Available Cannabinoids include the active constituents of Cannabis or are molecules that mimic the structure and/or function of these Cannabis-derived molecules. Cannabinoids produce many of their cellular and organ system effects by interacting with the well-characterized CB1 and CB2 receptors. However, it has become clear that not all effects of cannabinoid drugs are attributable to their interaction with CB1 and CB2 receptors. Evidence now demonstrates that cannabinoid agents produce effects by modulating activity of the entire array of cellular macromolecules targeted by other drug classes, including: other receptor types; ion channels; transporters; enzymes, and protein- and non-protein cellular structures. This review summarizes evidence for these interactions in the CNS and in cancer, and is organized according to the cellular targets involved. The CNS represents a well-studied area and cancer is emerging in terms of understanding mechanisms by which cannabinoids modulate their activity. Considering the CNS and cancer together allow identification of non-cannabinoid receptor targets that are shared and divergent in both systems. This comparative approach allows the identified targets to be compared and contrasted, suggesting potential new areas of investigation. It also provides insight into the diverse sources of efficacy employed by this interesting class of drugs. Obtaining a comprehensive understanding of the diverse mechanisms of cannabinoid action may lead to the design and development of therapeutic agents with greater efficacy and specificity for their cellular targets.

  4. Optimization of cAMP fluorescence dataset from ACTOne cannabinoid receptor 1 cell line

    Directory of Open Access Journals (Sweden)

    Chaela S. Presley

    2016-06-01

    Full Text Available The ACTOne cannabinoid receptor 1 functional system is comprised of transfected HEK cells with the parental cyclic nucleotide gated channel (CNG co-transfected with cannabinoid receptor 1 (CB1. The ACTOne CB1 cell line was evaluated for cAMP driven fluorescence by optimizing experimental conditions for sensitivity to forskolin and CP 55,940, reading time point, reliability of cell passage number, and pertussis inactivation of Gi/o.

  5. Detection of Cyclooxygenase-2-Derived Oxygenation Products of the Endogenous Cannabinoid 2-Arachidonoylglycerol in Mouse Brain.

    Science.gov (United States)

    Morgan, Amanda J; Kingsley, Philip J; Mitchener, Michelle M; Altemus, Megan; Patrick, Toni A; Gaulden, Andrew D; Marnett, Lawrence J; Patel, Sachin

    2018-05-09

    Cyclooxygenase-2 (COX-2) catalyzes the formation of prostaglandins, which are involved in immune regulation, vascular function, and synaptic signaling. COX-2 also inactivates the endogenous cannabinoid (eCB) 2-arachidonoylglycerol (2-AG) via oxygenation of its arachidonic acid backbone to form a variety of prostaglandin glyceryl esters (PG-Gs). Although this oxygenation reaction is readily observed in vitro and in intact cells, detection of COX-2-derived 2-AG oxygenation products has not been previously reported in neuronal tissue. Here we show that 2-AG is metabolized in the brain of transgenic COX-2-overexpressing mice and mice treated with lipopolysaccharide to form multiple species of PG-Gs that are detectable only when monoacylglycerol lipase is concomitantly blocked. Formation of these PG-Gs is prevented by acute pharmacological inhibition of COX-2. These data provide evidence that neuronal COX-2 is capable of oxygenating 2-AG to form a variety PG-Gs in vivo and support further investigation of the physiological functions of PG-Gs.

  6. Preclinical Science Regarding Cannabinoids as Analgesics: An Overview

    Directory of Open Access Journals (Sweden)

    ME Lynch

    2005-01-01

    Full Text Available Modern pharmacology of cannabinoids began in 1964 with the isolation and partial synthesis of delta-9-tetrahydrocannabinol, the main psychoactive agent in herbal cannabis. Since then, potent antinociceptive and antihyperalgesic effects of cannabinoid agonists in animal models of acute and chronic pain; the presence of cannabinoid receptors in pain-processing areas of the brain, spinal cord and periphery; and evidence supporting endogenous modulation of pain systems by cannabinoids has provided support that cannabinoids exhibit significant potential as analgesics. The present article presents an overview of the preclinical science.

  7. Proximal Tubular Cannabinoid-1 Receptor Regulates Obesity-Induced CKD.

    Science.gov (United States)

    Udi, Shiran; Hinden, Liad; Earley, Brian; Drori, Adi; Reuveni, Noa; Hadar, Rivka; Cinar, Resat; Nemirovski, Alina; Tam, Joseph

    2017-12-01

    Obesity-related structural and functional changes in the kidney develop early in the course of obesity and occur independently of hypertension, diabetes, and dyslipidemia. Activating the renal cannabinoid-1 receptor (CB 1 R) induces nephropathy, whereas CB 1 R blockade improves kidney function. Whether these effects are mediated via a specific cell type within the kidney remains unknown. Here, we show that specific deletion of CB 1 R in the renal proximal tubule cells did not protect the mice from obesity, but markedly attenuated the obesity-induced lipid accumulation in the kidney and renal dysfunction, injury, inflammation, and fibrosis. These effects associated with increased activation of liver kinase B1 and the energy sensor AMP-activated protein kinase, as well as enhanced fatty acid β -oxidation. Collectively, these findings indicate that renal proximal tubule cell CB 1 R contributes to the pathogenesis of obesity-induced renal lipotoxicity and nephropathy by regulating the liver kinase B1/AMP-activated protein kinase signaling pathway. Copyright © 2017 by the American Society of Nephrology.

  8. Signal Peptide and Denaturing Temperature are Critical Factors for Efficient Mammalian Expression and Immunoblotting of Cannabinoid Receptors*

    Science.gov (United States)

    WANG, Chenyun; WANG, Yingying; WANG, Miao; CHEN, Jiankui; YU, Nong; SONG, Shiping; KAMINSKI, Norbert E.; ZHANG, Wei

    2013-01-01

    Summary Many researchers employed mammalian expression system to artificially express cannabinoid receptors, but immunoblot data that directly prove efficient protein expression can hardly be seen in related research reports. In present study, we demonstrated cannabinoid receptor protein was not able to be properly expressed with routine mammalian expression system. This inefficient expression was rescued by endowing an exogenous signal peptide ahead of cannabinoid receptor peptide. In addition, the artificially synthesized cannabinoid receptor was found to aggregate under routine sample denaturing temperatures (i.e., ≥95°C), forming a large molecular weight band when analyzed by immunoblotting. Only denaturing temperatures ≤75°C yielded a clear band at the predicted molecular weight. Collectively, we showed that efficient mammalian expression of cannabinoid receptors need a signal peptide sequence, and described the requirement for a low sample denaturing temperature in immunoblot analysis. These findings provide very useful information for efficient mammalian expression and immunoblotting of membrane receptors. PMID:22528237

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

    DEFF Research Database (Denmark)

    Bouskila, Joseph; Javadi, Pasha; Casanova, Christian

    2013-01-01

    The presence of the cannabinoid receptor type 1 (CB1R) has been largely documented in the rodent and primate retinae in recent years. There is, however, some controversy concerning the presence of the CB2 receptor (CB2R) within the central nervous system. Only recently, CB2R has been found in the...

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

    Czech Academy of Sciences Publication Activity Database

    Hájková, Alena; Techlovská, Šárka; Dvořáková, Michaela; Chambers, Jayne Nicole; Kumpošt, Jiří; Hubálková, Pavla; Prezeau, L.; Blahoš, Jaroslav

    2016-01-01

    Roč. 107, léto (2016), s. 201-214 ISSN 0028-3908 R&D Projects: GA ČR GAP303/12/2408 Institutional support: RVO:68378050 Keywords : Seven transmembrane receptors * G-protein coupled receptors * Cannabinoid receptor 1 * Protein-protein interactions * Bias signaling * Receptor endocytosis Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 5.012, year: 2016

  11. Clinical Effects of Synthetic Cannabinoid Receptor Agonists Compared with Marijuana in Emergency Department Patients with Acute Drug Overdose.

    Science.gov (United States)

    Zaurova, Milana; Hoffman, Robert S; Vlahov, David; Manini, Alex F

    2016-12-01

    Synthetic cannabinoid receptor agonists (SCRAs) are heterogeneous compounds originally intended as probes of the endogenous cannabinoid system or as potential therapeutic agents. We assessed the clinical toxicity associated with recent SCRA use in a large cohort of drug overdose patients. This subgroup analysis of a large (n = 3739) drug overdose cohort study involved consecutive ED patients at two urban teaching hospitals collected between 2009 and 2013. Clinical characteristics of patients with the exposure to SCRAs (SRCA subgroup) were compared with those from patients who smoked traditional cannabinoids (marijuana subgroup). Data included demographics, exposure details, vital signs, mental status, and basic chemistries gathered as part of routine clinical care. Study outcomes included altered mental status and cardiotoxicity. Eighty-seven patients reported exposure to any cannabinoid, of whom 17 reported SCRAs (17 cases, 70 controls, mean age 38.9 years, 77 % males, 31 % Hispanic). There were no significant differences between SRCA and marijuana with respect to demographics (age, gender, and race/ethnicity), exposure history (suicidality, misuse, and intent), vital signs, or serum chemistries. Mental status varied between SRCA and marijuana, with agitation significantly more likely in SCRA subgroup (OR = 3.8, CI = 1.2-11.9). Cardiotoxicity was more pronounced in the SCRA subgroup with dysrhythmia significantly more likely (OR = 9.2, CI = 1.0-108). In the first clinical study comparing the adverse effects of SCRA overdose vs. marijuana controls in an ED population, we found that SCRA overdoses had significantly pronounced neurotoxicity and cardiotoxicity compared with marijuana.

  12. Cannabinoid Receptor Signaling in Central Regulation of Feeding Behavior: A Mini-Review

    Directory of Open Access Journals (Sweden)

    Marco Koch

    2017-05-01

    Full Text Available Cannabinoids are lipid messengers that modulate a variety of physiological processes and modify the generation of specific behaviors. In this regard, the cannabinoid receptor type 1 (CB1 represents the most relevant target molecule of cannabinoids so far. One main function of central CB1 signaling is to maintain whole body energy homeostasis. Thus, cannabinoids functionally interact with classical neurotransmitters in neural networks that control energy metabolism and feeding behavior. The promotion of CB1 signaling can increase appetite and stimulate feeding, while blockade of CB1 suppresses hunger and induces hypophagia. However, in order to treat overeating, pharmacological blockade of CB1 by the inverse agonist rimonabant not only suppressed feeding but also resulted in psychiatric side effects. Therefore, research within the last decade focused on deciphering the underlying cellular and molecular mechanisms of central cannabinoid signaling that control feeding and other behaviors, with the overall aim still being the identification of specific targets to develop safe pharmacological interventions for the treatment of obesity. Today, many studies unraveled the subcellular localization of CB1 and the function of cannabinoids in neurons and glial cells within circumscribed brain regions that represent integral parts of neural circuitries controlling feeding behavior. Here, these novel experimental findings will be summarized and recent advances in understanding the mechanisms of CB1-dependent cannabinoid signaling being relevant for central regulation of feeding behavior will be highlighted. Finally, presumed alternative pathways of cannabinoids that are not driven by CB1 activation but also contributing to control of feeding behavior will be introduced.

  13. Loss of cannabinoid receptor CB1 induces preterm birth.

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    Haibin Wang

    2008-10-01

    Full Text Available 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.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.CB1 deficiency altering normal progesterone and estrogen levels induces preterm birth in mice. This defect is independent of prostaglandins produced by cyclooxygenase-1. Moreover, CB1 inactivation resulted in

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

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    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.

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

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    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.…

  16. Genetic Variations in the Human Cannabinoid Receptor Gene Are Associated with Happiness

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

    2014-01-01

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

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

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    Masahiro Matsunaga

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

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

    Science.gov (United States)

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

    2014-01-01

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

  19. Spatial distribution of cannabinoid receptor type 1 (CB1 in normal canine central and peripheral nervous system.

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    Jessica Freundt-Revilla

    Full Text Available The endocannabinoid system is a regulatory pathway consisting of two main types of cannabinoid receptors (CB1 and CB2 and their endogenous ligands, the endocannabinoids. The CB1 receptor is highly expressed in the central and peripheral nervous systems (PNS in mammalians and is involved in neuromodulatory functions. Since endocannabinoids were shown to be elevated in cerebrospinal fluid of epileptic dogs, knowledge about the species specific CB receptor expression in the nervous system is required. Therefore, we assessed the spatial distribution of CB1 receptors in the normal canine CNS and PNS. Immunohistochemistry of several regions of the brain, spinal cord and peripheral nerves from a healthy four-week-old puppy, three six-month-old dogs, and one ten-year-old dog revealed strong dot-like immunoreactivity in the neuropil of the cerebral cortex, Cornu Ammonis (CA and dentate gyrus of the hippocampus, midbrain, cerebellum, medulla oblongata and grey matter of the spinal cord. Dense CB1 expression was found in fibres of the globus pallidus and substantia nigra surrounding immunonegative neurons. Astrocytes were constantly positive in all examined regions. CB1 labelled neurons and satellite cells of the dorsal root ganglia, and myelinating Schwann cells in the PNS. These results demonstrate for the first time the spatial distribution of CB1 receptors in the healthy canine CNS and PNS. These results can be used as a basis for further studies aiming to elucidate the physiological consequences of this particular anatomical and cellular distribution.

  20. Acute cannabinoids impair working memory through astroglial CB1 receptor modulation of hippocampal LTD.

    Science.gov (United States)

    Han, Jing; Kesner, Philip; Metna-Laurent, Mathilde; Duan, Tingting; Xu, Lin; Georges, Francois; Koehl, Muriel; Abrous, Djoher Nora; Mendizabal-Zubiaga, Juan; Grandes, Pedro; Liu, Qingsong; Bai, Guang; Wang, Wei; Xiong, Lize; Ren, Wei; Marsicano, Giovanni; Zhang, Xia

    2012-03-02

    Impairment of working memory is one of the most important deleterious effects of marijuana intoxication in humans, but its underlying mechanisms are presently unknown. Here, we demonstrate that the impairment of spatial working memory (SWM) and in vivo long-term depression (LTD) of synaptic strength at hippocampal CA3-CA1 synapses, induced by an acute exposure of exogenous cannabinoids, is fully abolished in conditional mutant mice lacking type-1 cannabinoid receptors (CB(1)R) in brain astroglial cells but is conserved in mice lacking CB(1)R in glutamatergic or GABAergic neurons. Blockade of neuronal glutamate N-methyl-D-aspartate receptors (NMDAR) and of synaptic trafficking of glutamate α-amino-3-hydroxy-5-methyl-isoxazole propionic acid receptors (AMPAR) also abolishes cannabinoid effects on SWM and LTD induction and expression. We conclude that the impairment of working memory by marijuana and cannabinoids is due to the activation of astroglial CB(1)R and is associated with astroglia-dependent hippocampal LTD in vivo. Copyright © 2012 Elsevier Inc. All rights reserved.

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

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    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.

  2. Localization and function of the cannabinoid CB1 receptor in the anterolateral bed nucleus of the stria terminalis.

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    Nagore Puente

    Full Text Available BACKGROUND: The bed nucleus of the stria terminalis (BNST is involved in behaviors related to natural reward, drug addiction and stress. In spite of the emerging role of the endogenous cannabinoid (eCB system in these behaviors, little is known about the anatomy and function of this system in the anterolateral BNST (alBNST. The aim of this study was to provide a detailed morphological characterization of the localization of the cannabinoid 1 (CB1 receptor a necessary step toward a better understanding of the physiological roles of the eCB system in this region of the brain. METHODOLOGY/PRINCIPAL FINDINGS: We have combined anatomical approaches at the confocal and electron microscopy level to ex-vivo electrophysiological techniques. Here, we report that CB1 is localized on presynaptic membranes of about 55% of immunopositive synaptic terminals for the vesicular glutamate transporter 1 (vGluT1, which contain abundant spherical, clear synaptic vesicles and make asymmetrical synapses with alBNST neurons. About 64% of vGluT1 immunonegative synaptic terminals show CB1 immunolabeling. Furthermore, 30% and 35% of presynaptic boutons localize CB1 in alBNST of conditional mutant mice lacking CB1 mainly from GABAergic neurons (GABA-CB1-KO mice and mainly from cortical glutamatergic neurons (Glu-CB1-KO mice, respectively. Extracellular field recordings and whole cell patch clamp in the alBNST rat brain slice preparation revealed that activation of CB1 strongly inhibits excitatory and inhibitory synaptic transmission. CONCLUSIONS/SIGNIFICANCE: This study supports the anterolateral BNST as a potential neuronal substrate of the effects of cannabinoids on stress-related behaviors.

  3. Cannabinoid CB2 Receptors Contribute to Upregulation of β-endorphin in Inflamed Skin Tissues by Electroacupuncture

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    Su Tang-feng

    2011-12-01

    Full Text Available Abstract Background Electroacupuncture (EA can produce analgesia by increasing the β-endorphin level and activation of peripheral μ-opioid receptors in inflamed tissues. Endogenous cannabinoids and peripheral cannabinoid CB2 receptors (CB2Rs are also involved in the antinociceptive effect of EA on inflammatory pain. However, little is known about how peripheral CB2Rs interact with the endogenous opioid system at the inflammatory site and how this interaction contributes to the antinociceptive effect of EA on inflammatory pain. In this study, we determined the role of peripheral CB2Rs in the effects of EA on the expression of β-endorphin in inflamed skin tissues and inflammatory pain. Results Inflammatory pain was induced by injection of complete Freund's adjuvant into the left hindpaw of rats. Thermal hyperalgesia was tested with a radiant heat stimulus, and mechanical allodynia was quantified using von Frey filaments. The mRNA level of POMC and protein level of β-endorphin were quantified by real-time PCR and Western blotting, respectively. The β-endorphin-containing keratinocytes and immune cells in the inflamed skin tissues were detected by double-immunofluorescence labeling. The CB2R agonist AM1241 or EA significantly reduced thermal hyperalgesia and mechanical allodynia, whereas the selective μ-opioid receptor antagonist β-funaltrexamine significantly attenuated the antinociceptive effect produced by them. AM1241 or EA significantly increased the mRNA level of POMC and the protein level of β-endorphin in inflamed skin tissues, and these effects were significantly attenuated by pretreatment with the CB2R antagonist AM630. AM1241 or EA also significantly increased the percentage of β-endorphin-immunoreactive keratinocytes, macrophages, and T-lymphocytes in inflamed skin tissues, and these effects were blocked by AM630. Conclusions EA and CB2R stimulation reduce inflammatory pain through activation of μ-opioid receptors. EA increases

  4. Interaction between Antagonist of Cannabinoid Receptor and Antagonist of Adrenergic Receptor on Anxiety in Male Rat

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    Alireza Komaki

    2014-07-01

    Full Text Available Introduction: Anxiety is among the most common and treatable mental disorders. Adrenergic and cannabinoid systems have an important role in the neurobiology of anxiety. The elevated plus-maze (EPM has broadly been used to investigate anxiolytic and anxiogenic compounds. The present study investigated the effects of intraperitoneal (IP injection of cannabinoid CB1 receptor antagonist (AM251 in the presence of alpha-1 adrenergic antagonist (Prazosin on rat behavior in the EPM. Methods: In this study, the data were obtained from male Wistar rat, which weighing 200- 250 g. Animal behavior in EPM were videotaped and saved in computer for 10 min after IP injection of saline, AM251 (0.3 mg/kg, Prazosin (0.3 mg/kg and AM251 + Prazosin, subsequently scored for conventional indices of anxiety. During the test period, the number of open and closed arms entries, the percentage of entries into the open arms of the EPM, and the spent time in open and closed arms were recorded. Diazepam was considered as a positive control drug with anxiolytic effect (0.3, 0.6, 1.2 mg/kg. Results: Diazepam increased the number of open arm entries and the percentage of spent time on the open arms. IP injection of AM251 before EPM trial decreased open arms exploration and open arm entry. Whereas, Prazosin increased open arms exploration and open arm entry. This study showed that both substances in simultaneous injection have conflicting effects on the responses of each of these two compounds in a single injection. Discussion: Injection of CB1 receptor antagonist may have an anxiogenic profile in rat, whereas adrenergic antagonist has an anxiolytic effect. Further investigations are essential for better understanding of anxiolytic and anxiogenic properties and neurobiological mechanisms of action and probable interactions of the two systems.

  5. Interaction between Antagonist of Cannabinoid Receptor and Antagonist of Adrenergic Receptor on Anxiety in Male Rat.

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    Komaki, Alireza; Abdollahzadeh, Fatemeh; Sarihi, Abdolrahman; Shahidi, Siamak; Salehi, Iraj

    2014-01-01

    Anxiety is among the most common and treatable mental disorders. Adrenergic and cannabinoid systems have an important role in the neurobiology of anxiety. The elevated plus-maze (EPM) has broadly been used to investigate anxiolytic and anxiogenic compounds. The present study investigated the effects of intraperitoneal (IP) injection of cannabinoid CB1 receptor antagonist (AM251) in the presence of alpha-1 adrenergic antagonist (Prazosin) on rat behavior in the EPM. In this study, the data were obtained from male Wistar rat, which weighing 200- 250 g. Animal behavior in EPM were videotaped and saved in computer for 10 min after IP injection of saline, AM251 (0.3 mg/kg), Prazosin (0.3 mg/kg) and AM251 + Prazosin, subsequently scored for conventional indices of anxiety. During the test period, the number of open and closed arms entries, the percentage of entries into the open arms of the EPM, and the spent time in open and closed arms were recorded. Diazepam was considered as a positive control drug with anxiolytic effect (0.3, 0.6, 1.2 mg/kg). Diazepam increased the number of open arm entries and the percentage of spent time on the open arms. IP injection of AM251 before EPM trial decreased open arms exploration and open arm entry. Whereas, Prazosin increased open arms exploration and open arm entry. This study showed that both substances in simultaneous injection have conflicting effects on the responses of each of these two compounds in a single injection. Injection of CB1 receptor antagonist may have an anxiogenic profile in rat, whereas adrenergic antagonist has an anxiolytic effect. Further investigations are essential for better understanding of anxiolytic and anxiogenic properties and neurobiological mechanisms of action and probable interactions of the two systems.

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

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    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 potent cannabinoid receptor agonists WIN55,212-2 (0.05, 0.5 or 5 pmol per 50 nl) and HU-210 (0.5 pmol per 50 nl) or the CB1 receptor antagonist/inverse agonist AM281 (1 pmol per 100 nl) were microinjected into the RVLM of urethane-anaesthetised, immobilised and mechanically ventilated male Sprague–Dawley rats (n=22). Changes in splanchnic nerve activity (sSNA), phrenic nerve activity (PNA), mean arterial pressure (MAP) and heart rate (HR) in response to cannabinoid administration were recorded. The CB1 receptor gene was expressed throughout the VLM. Unilateral microinjection of WIN55,212-2 into the RVLM evoked short-latency, dose-dependent increases in sSNA (0.5 pmol; 175±8%, n=5) and MAP (0.5 pmol; 26±3%, n=8) and abolished PNA (0.5 pmol; duration of apnoea: 5.4±0.4 s, n=8), with little change in HR (P<0.005). HU-210, structurally related to Δ9-tetrahydrocannabinol (THC), evoked similar effects when microinjected into the RVLM (n=4). Surprisingly, prior microinjection of AM281 produced agonist-like effects, as well as significantly attenuated the response to subsequent injection of WIN55,212-2 (0.5 pmol, n=4). The present study reveals CB1 receptor gene expression in the rat VLM and demonstrates sympathoexcitation, hypertension and respiratory inhibition in response to RVLM-administered cannabinoids. These findings suggest a novel link between CB1 receptors in this region of the hindbrain and the central cardiorespiratory effects of cannabinoids. The extent to which these

  7. 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...

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

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    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.

  9. Cannabinoids and Innate Immunity: Taking a Toll on Neuroinflammation

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    Eric J. Downer

    2011-01-01

    Full Text Available The biologically active components of cannabis have therapeutic potential in neuroinflammatory disorders due to their anti-inflammatory propensity. Cannabinoids influence immune function in both the peripheral and the central nervous system (CNS, and the components of the cannabinoid system, the cannabinoid receptors and their endogenous ligands (endocannabinoids, have been detected on immune cells as well as in brain glia. Neuroinflammation is the complex innate immune response of neural tissue to control infection and eliminate pathogens, and Toll-like receptors (TLRs, a major family of pattern recognition receptors (PRRs that mediate innate immunity, have emerged as players in the neuroinflammatory processes underpinning various CNS diseases. This review will highlight evidence that cannabinoids interact with the immune system by impacting TLR-mediated signaling events, which may provide cues for devising novel therapeutic approaches for cannabinoid ligands.

  10. BIASED AGONISM OF THREE DIFFERENT CANNABINOID RECEPTOR AGONISTS IN MOUSE BRAIN CORTEX

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    Rebeca Diez-Alarcia

    2016-11-01

    Full Text Available Cannabinoid receptors are able to couple to different families of G-proteins when activated by an agonist drug. It has been suggested that different intracellular responses may be activated depending on the ligand. The goal of the present study was to characterize the pattern of G protein subunit stimulation triggered by three different cannabinoid ligands, THC, WIN55212-2 and ACEA in mouse brain cortex.Stimulation of the [35S]GTPS binding coupled to specific immunoprecipitation with antibodies against different subtypes of G proteins (Gαi1, Gαi2, Gαi3, Gαo, Gαz, Gαs, Gαq/11, and Gα12/13, in the presence of Δ9-THC, WIN55212-2 and ACEA (submaximal concentration 10 µM was determined by Scintillation Proximity Assay (SPA technique in mouse cortex of wild type, CB1 knock-out, CB2 knock-out and CB1/CB2 double knock-out mice. Results show that, in mouse brain cortex, cannabinoid agonists are able to significantly stimulate not only the classical inhibitory Gαi/o subunits but also other G subunits like Gαz, Gαq/11, and Gα12/13. Moreover, the specific pattern of G protein subunit activation is different depending on the ligand. In conclusion, our results demonstrate that, in mice brain native tissue, different exogenous cannabinoid ligands are able to selectively activate different inhibitory and non-inhibitory Gα protein subtypes, through the activation of CB1 and/or CB2 receptors. Results of the present study may help to understand the specific molecular pathways involved in the pharmacological effects of cannabinoid-derived drugs.

  11. Cannabinoid-induced cell death in endometrial cancer cells: involvement of TRPV1 receptors in apoptosis.

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    Fonseca, B M; Correia-da-Silva, G; Teixeira, N A

    2018-05-01

    Among a variety of phytocannabinoids, Δ 9 -tetrahydrocannabinol (THC) and cannabidiol (CBD) are the most promising therapeutic compounds. Besides the well-known palliative effects in cancer patients, cannabinoids have been shown to inhibit in vitro growth of tumor cells. Likewise, the major endocannabinoids (eCBs), anandamide (AEA) and 2-arachidonoylglycerol (2-AG), induce tumor cell death. The purpose of the present study was to characterize cannabinoid elements and evaluate the effect of cannabinoids in endometrial cancer cell viability. The presence of cannabinoid receptors, transient receptor potential vanilloid 1 (TRPV1), and endocannabinoid-metabolizing enzymes were determined by qRT-PCR and Western blot. We also examined the effects and the underlying mechanisms induced by eCBs and phytocannabinoids in endometrial cancer cell viability. Besides TRPV1, both EC cell lines express all the constituents of the endocannabinoid system. We observed that at concentrations higher than 5 μM, eCBs and CBD induced a significant reduction in cell viability in both Ishikawa and Hec50co cells, whereas THC did not cause any effect. In Ishikawa cells, contrary to Hec50co, treatment with AEA and CBD resulted in an increase in the levels of activated caspase -3/-7, in cleaved PARP, and in reactive oxygen species generation, confirming that the reduction in cell viability observed in the MTT assay was caused by the activation of the apoptotic pathway. Finally, these effects were dependent on TRPV1 activation and intracellular calcium levels. These data indicate that cannabinoids modulate endometrial cancer cell death. Selective targeting of TPRV1 by AEA, CBD, or other stable analogues may be an attractive research area for the treatment of estrogen-dependent endometrial carcinoma. Our data further support the evaluation of CBD and CBD-rich extracts for the potential treatment of endometrial cancer, particularly, that has become non-responsive to common therapies.

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

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    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.

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

    DEFF Research Database (Denmark)

    Cécyre, Bruno; Thomas, Sébastien; Ptito, Maurice

    2014-01-01

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

  14. Endogenous fatty acid ethanolamides suppress nicotine-induced activation of mesolimbic dopamine neurons through nuclear receptors.

    Science.gov (United States)

    Melis, Miriam; Pillolla, Giuliano; Luchicchi, Antonio; Muntoni, Anna Lisa; Yasar, Sevil; Goldberg, Steven R; Pistis, Marco

    2008-12-17

    Nicotine stimulates the activity of mesolimbic dopamine neurons, which is believed to mediate the rewarding and addictive properties of tobacco use. Accumulating evidence suggests that the endocannabinoid system might play a major role in neuronal mechanisms underlying the rewarding properties of drugs of abuse, including nicotine. Here, we investigated the modulation of nicotine effects by the endocannabinoid system on dopamine neurons in the ventral tegmental area with electrophysiological techniques in vivo and in vitro. We discovered that pharmacological inhibition of fatty acid amide hydrolase (FAAH), the enzyme that catabolizes fatty acid ethanolamides, among which the endocannabinoid anandamide (AEA) is the best known, suppressed nicotine-induced excitation of dopamine cells. Importantly, this effect was mimicked by the administration of the FAAH substrates oleoylethanolamide (OEA) and palmitoylethanolamide (PEA), but not methanandamide, the hydrolysis resistant analog of AEA. OEA and PEA are naturally occurring lipid signaling molecules structurally related to AEA, but devoid of affinity for cannabinoid receptors. They blocked the effects of nicotine by activation of the peroxisome proliferator-activated receptor-alpha (PPAR-alpha), a nuclear receptor transcription factor involved in several aspects of lipid metabolism and energy balance. Activation of PPAR-alpha triggered a nongenomic stimulation of tyrosine kinases, which might lead to phosphorylation and negative regulation of neuronal nicotinic acetylcholine receptors. These data indicate for the first time that the anorexic lipids OEA and PEA possess neuromodulatory properties as endogenous ligands of PPAR-alpha in the brain and provide a potential new target for the treatment of nicotine addiction.

  15. 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)

    Rajasekaran, Maheswari; Brents, Lisa K.; Franks, Lirit N.; Moran, Jeffery H.; Prather, Paul L.

    2013-01-01

    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 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 2 Rs), this study investigated the affinity and intrinsic activity of JWH-018, JWH-073 and several monohydroxylated metabolites at human CB 2 Rs (hCB 2 Rs). The affinity of cannabinoids for hCB 2 Rs was determined by competition binding studies employing CHO-hCB 2 membranes. Intrinsic activity of compounds was assessed by G-protein activation and adenylyl cyclase (AC)-inhibition in CHO-hCB 2 cells. JWH-073, JWH-018 and several of their human metabolites exhibit nanomolar affinity and act as potent agonists at hCB 2 Rs. Furthermore, a major omega hydroxyl metabolite of JWH-073 (JWH-073-M5) binds to CB 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 9 -tetrahydrocannabinol (Δ 9 -THC), JWH-018, JWH-018-M5 and JWH-073-M5 require significantly less CB 2 R occupancy to produce similar levels of AC-inhibition, indicating that these compounds may more efficiently couple CB 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 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 1 and CB 2 Rs. - Highlights: • JWH-018 and JWH-073 are synthetic cannabinoids present in abused K2

  16. 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

  17. 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.

  18. Impact of Cannabinoid Receptor Ligands on Sensitisation to Methamphetamine Effects on Rat Locomotor Behaviour

    Directory of Open Access Journals (Sweden)

    L. Landa

    2008-01-01

    Full Text Available The repeated administration of various drugs of abuse may lead to a gradually increased behavioural response to these substances, particularly an increase in locomotion and stereotypies may occur. This phenomenon is well known and described as behavioural sensitisation. An increased response to the drug tested, elicited by previous repeated administration of another drug is recognised as cross-sensitisation. Based on our earlier experiences with studies on mice, which confirmed sensitisation to methamphetamine and described cross-sensitisation to methamphetamine after pre-treatment with cannabinoid CB1 receptor agonist, we focused the present study on the use of another typical laboratory animal - the rat. A biological validity of the sensitisation phenomenon was expected to be enhanced if the results of both mouse and rat studies were conformable. Similar investigation in rats brought very similar results to those described earlier in mice. However, at least some interspecies differences were noted in the rat susceptibility to the development of sensitisation to methamphetamine effects. Comparing to mice, it was more demanding to titrate a dose of methamphetamine producing behavioural sensitisation. Furthermore, we were not able to provoke cross-sensitisation by repeated administration of cannabinoid CB1 receptor agonist methanandamide and similarly, we did not demonstrate the suppression of cross-sensitisation in rats that were repeatedly given combined pre-treatment with cannabinoid CB1 receptor antagonist AM 251 and methamphetamine. Finally, unlike mice, an alternative behavioural change was registered after repeated methamphetamine treatment instead: the occurrence of stereotypic behaviour (nose rubbing.

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

    International Nuclear Information System (INIS)

    Takeda, Shuso; Yamaori, Satoshi; Motoya, Erina; Matsunaga, Tamihide; Kimura, Toshiyuki; Yamamoto, Ikuo; Watanabe, Kazuhito

    2008-01-01

    We recently reported that Δ 9 -tetrahydrocannabinol (Δ 9 -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 Δ 9 -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 Δ 9 -THC in the presence of CB receptors, it was revealed that Δ 9 -THC could exert upregulation of living cells in the absence of the receptors. Interestingly, Δ 9 -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, Δ 9 -THC can stimulate the proliferation of MCF-7 cells by modulating, at least in part, HER2 transcription

  20. SR 144528, the first potent and selective antagonist of the CB2 cannabinoid receptor.

    Science.gov (United States)

    Rinaldi-Carmona, M; Barth, F; Millan, J; Derocq, J M; Casellas, P; Congy, C; Oustric, D; Sarran, M; Bouaboula, M; Calandra, B; Portier, M; Shire, D; Brelière, J C; Le Fur, G L

    1998-02-01

    Based on both binding and functional data, this study introduces SR 144528 as the first, highly potent, selective and orally active antagonist for the CB2 receptor. This compound which displays subnanomolar affinity (Ki = 0.6 nM) for both the rat spleen and cloned human CB2 receptors has a 700-fold lower affinity (Ki = 400 nM) for both the rat brain and cloned human CB1 receptors. Furthermore it shows no affinity for any of the more than 70 receptors, ion channels or enzymes investigated (IC50 > 10 microM). In vitro, SR 144528 antagonizes the inhibitory effects of the cannabinoid receptor agonist CP 55,940 on forskolin-stimulated adenylyl cyclase activity in cell lines permanently expressing the h CB2 receptor (EC50 = 10 nM) but not in cells expressing the h CB1 (no effect at 10 microM). Furthermore, SR 144528 is able to selectively block the mitogen-activated protein kinase activity induced by CP 55,940 in cell lines expressing h CB2 (IC50 = 39 nM) whereas in cells expressing h CB1 an IC50 value of more than 1 microM is found. In addition, SR 144528 is shown to antagonize the stimulating effects of CP 55,940 on human tonsillar B-cell activation evoked by cross-linking of surface Igs (IC50 = 20 nM). In vivo, after oral administration SR 144528 totally displaced the ex vivo [3H]-CP 55,940 binding to mouse spleen membranes (ED50 = 0.35 mg/kg) with a long duration of action. In contrast, after the oral route it does not interact with the cannabinoid receptor expressed in the mouse brain (CB1). It is expected that SR 144528 will provide a powerful tool to investigate the in vivo functions of the cannabinoid system in the immune response.

  1. 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

  2. Elevation of endogenous anandamide impairs LTP, learning, and memory through CB1 receptor signaling in mice.

    Science.gov (United States)

    Basavarajappa, Balapal S; Nagre, Nagaraja N; Xie, Shan; Subbanna, Shivakumar

    2014-07-01

    In rodents, many exogenous and endogenous cannabinoids, such as anandamide (AEA) and 2-arachidonyl glycerol (2-AG), have been shown to play an important role in certain hippocampal memory processes. However, the mechanisms by which endogenous AEA regulate this processes are not well understood. Here the effects of AEA on long-term potentiation (LTP), hippocampal-dependent learning and memory tasks, pERK1/2, pCaMKIV, and pCREB signaling events in both cannabinoid receptor type 1 (CB1R) wild-type (WT) and knockout (KO) mice were assessed following administration of URB597, an inhibitor of the fatty acid amide hydrolase (FAAH). Acute administration of URB597 enhanced AEA levels without affecting the levels of 2-AG or CB1R in the hippocampus and neocortex as compared to vehicle. In hippocampal slices, URB597 impaired LTP in CB1R WT but not in KO littermates. URB597 impaired object recognition, spontaneous alternation and spatial memory in the Y-maze test in CB1R WT mice but not in KO mice. Furthermore, URB597 enhanced ERK phosphorylation in WT without affecting total ERK levels in WT or KO mice. URB597 impaired CaMKIV and CREB phosphorylation in WT but not in KO mice. CB1R KO mice have a lower pCaMKIV/CaMKIV ratio and higher pCREB/CREB ratio as compared to WT littermates. Our results indicate that pharmacologically elevated AEA impair LTP, learning and memory and inhibit CaMKIV and CREB phosphorylation, via the activation of CB1Rs. Collectively, these findings also suggest that pharmacological elevation of AEA beyond normal concentrations is also detrimental for the underlying physiological responses. © 2014 Wiley Periodicals, Inc.

  3. Δ9-Tetrahydrocannabinol attenuates allogeneic host-versus-graft response and delays skin graft rejection through activation of cannabinoid receptor 1 and induction of myeloid-derived suppressor cells

    Science.gov (United States)

    Sido, Jessica M.; Nagarkatti, Prakash S.; Nagarkatti, Mitzi

    2015-01-01

    Immune cells have been shown to express cannabinoid receptors and to produce endogenous ligands. Moreover, activation of cannabinoid receptors on immune cells has been shown to trigger potent immunosuppression. Despite such studies, the role of cannabinoids in transplantation, specifically to prevent allograft rejection, has not, to our knowledge, been investigated previously. In the current study, we tested the effect of THC on the suppression of HvGD as well as rejection of skin allografts. To this end, we studied HvGD by injecting H-2k splenocytes into H-2b mice and analyzing the immune response in the draining ingLNs. THC treatment significantly reduced T cell proliferation and activation in draining LNs of the recipient mice and decreased early stage rejection-indicator cytokines, including IL-2 and IFN-γ. THC treatment also increased the allogeneic skin graft survival. THC treatment in HvGD mice led to induction of MDSCs. Using MDSC depletion studies as well as adoptive transfer experiments, we found that THC-induced MDSCs were necessary for attenuation of HvGD. Additionally, using pharmacological inhibitors of CB1 and CB2 receptors and CB1 and CB2 knockout mice, we found that THC was working preferentially through CB1. Together, our research shows, for the first time to our knowledge, that targeting cannabinoid receptors may provide a novel treatment modality to attenuate HvGD and prevent allograft rejection. PMID:26034207

  4. Scotopic vision in the monkey is modulated by the G protein-coupled receptor 55

    DEFF Research Database (Denmark)

    Bouskila, Joseph; Harrar, Vanessa; Javadi, Pasha

    2016-01-01

    The endogenous cannabinoid system plays important roles in the retina of mice and monkeys via their classic CB1 and CB2 receptors. We have previously reported that the G protein-coupled receptor 55 (GPR55), a putative cannabinoid receptor, is exclusively expressed in rod photoreceptors in the mon......The endogenous cannabinoid system plays important roles in the retina of mice and monkeys via their classic CB1 and CB2 receptors. We have previously reported that the G protein-coupled receptor 55 (GPR55), a putative cannabinoid receptor, is exclusively expressed in rod photoreceptors...

  5. Effects of cannabinoid and vanilloid receptor agonists and their interaction on learning and memory in rats.

    Science.gov (United States)

    Shiri, Mariam; Komaki, Alireza; Oryan, Shahrbanoo; Taheri, Masoumeh; Komaki, Hamidreza; Etaee, Farshid

    2017-04-01

    Despite previous findings on the effects of cannabinoid and vanilloid systems on learning and memory, the effects of the combined stimulation of these 2 systems on learning and memory have not been studied. Therefore, in this study, we tested the interactive effects of cannabinoid and vanilloid systems on learning and memory in rats by using passive avoidance learning (PAL) tests. Forty male Wistar rats were divided into the following 4 groups: (1) control (DMSO+saline), (2) WIN55,212-2, (3) capsaicin, and (4) WIN55,212-2 + capsaicin. On test day, capsaicin, a vanilloid receptor type 1 (TRPV1) agonist, or WIN55,212-2, a cannabinoid receptor (CB 1 /CB 2 ) agonist, or both substances were injected intraperitoneally. Compared to the control group, the group treated with capsaicin (TRPV1 agonist) had better scores in the PAL acquisition and retention test, whereas treatment with WIN55,212-2 (CB 1 /CB 2 agonist) decreased the test scores. Capsaicin partly reduced the effects of WIN55,212-2 on PAL and memory. We conclude that the acute administration of a TRPV1 agonist improves the rats' cognitive performance in PAL tasks and that a vanilloid-related mechanism may underlie the agonistic effect of WIN55,212-2 on learning and memory.

  6. Exposure to a Highly Caloric Palatable Diet during the Perinatal Period Affects the Expression of the Endogenous Cannabinoid System in the Brain, Liver and Adipose Tissue of Adult Rat Offspring.

    Directory of Open Access Journals (Sweden)

    María Teresa Ramírez-López

    Full Text Available Recent studies have linked gestational exposure to highly caloric diets with a disrupted endogenous cannabinoid system (ECS. In the present study, we have extended these studies by analyzing the impact of the exposure to a palatable diet during gestation and lactation on a the adult expression of endocannabinoid-related behaviors, b the metabolic profile of adult offspring and c the mRNA expression of the signaling machinery of the ECS in the hypothalamus, the liver and the adipose tissue of adult offspring of both sexes. Exposure to a palatable diet resulted in a sex-dimorphic and perinatal diet specific feeding behaviors, including the differential response to the inhibitory effects of the cannabinoid receptor inverse agonist AM251, b features of metabolic syndrome including increased adiposity, hyperleptinemia, hypertriglyceridemia and hypercholesterolemia and c tissue and sex-specific changes in the expression of both CB1 and CB2 receptors and in that of the endocannabinoid-degrading enzymes FAAH and MAGL, being the adipose tissue the most affected organ analyzed. Since the effects were observed in adult animals that were weaned while consuming a normal diet, the present results indicate that the ECS is one of the targets of maternal programming of the offspring energy expenditure. These results clearly indicate that the maternal diet has long-term effects on the development of pups through multiple alterations of signaling homeostatic pathways that include the ECS. The potential relevance of these alterations for the current obesity epidemic is discussed.

  7. Effects of cannabinoid CB1 receptor antagonist rimonabant in consolidation and reconsolidation of methamphetamine reward memory in mice.

    Science.gov (United States)

    Yu, Lu-lu; Wang, Xue-yi; Zhao, Mei; Liu, Yu; Li, Yan-qin; Li, Fang-qiong; Wang, Xiaoyi; Xue, Yan-xue; Lu, Lin

    2009-06-01

    Previous studies have shown that cannabinoid CB1 receptors play an important role in specific aspects of learning and memory, yet there has been no systematic study focusing on the involvement of cannabinoid CB1 receptors in methamphetamine-related reward memory. The purpose of this study was to examine whether rimonabant, a cannabinoid CB1 receptor antagonist, would disrupt the consolidation and reconsolidation of methamphetamine-related reward memory, using conditioned place preference paradigm (CPP). Separate groups of male Kunming mice were trained to acquire methamphetamine CPP. Vehicle or rimonabant (1 mg/kg or 3 mg/kg, i.p.) was given at different time points: immediately after each CPP training session (consolidation), 30 min before the reactivation of CPP (retrieval), or immediately after the reactivation of CPP (reconsolidation). Methamphetamine CPP was retested 24 h and 1 and 2 weeks after rimonabant administration. Rimonabant at doses of 1 and 3 mg/kg significantly inhibited the consolidation of methamphetamine CPP. Only high-dose rimonabant (3 mg/kg) disrupted the retrieval and reconsolidation of methamphetamine CPP. Rimonabant had no effect on methamphetamine CPP in the absence of methamphetamine CPP reactivation. Our findings suggest that cannabinoid CB1 receptors play a major role in methamphetamine reward memory, and cannabinoid CB1 receptor antagonists may be a potential pharmacotherapy to manage relapse associated with drug-reward-related memory.

  8. Synthetic Cannabinoids.

    Science.gov (United States)

    Mills, Brooke; Yepes, Andres; Nugent, Kenneth

    2015-07-01

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

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

    NARCIS (Netherlands)

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

    2011-01-01

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

  10. DMPD: Endogenous ligands of Toll-like receptors. [Dynamic Macrophage Pathway CSML Database

    Lifescience Database Archive (English)

    Full Text Available 15178705 Endogenous ligands of Toll-like receptors. Tsan MF, Gao B. J Leukoc Biol. ...2004 Sep;76(3):514-9. Epub 2004 Jun 3. (.png) (.svg) (.html) (.csml) Show Endogenous ligands of Toll-like re...ceptors. PubmedID 15178705 Title Endogenous ligands of Toll-like receptors. Authors Tsan MF, Gao B. Publicat

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

    International Nuclear Information System (INIS)

    Silva, L.C.R.; Romero, T.R.L.; Guzzo, L.S.; Duarte, I.D.G.

    2012-01-01

    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 2 (PGE 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 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 1 and CB 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 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 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 the NSAIDs dipyrone, diclofenac

  12. 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

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

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    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

  14. The type 2 cannabinoid receptor regulates susceptibility to osteoarthritis in mice.

    Science.gov (United States)

    Sophocleous, A; Börjesson, A E; Salter, D M; Ralston, S H

    2015-09-01

    Cannabinoid receptors and their ligands have been implicated in the regulation of various physiological processes but their role in osteoarthritis has not been investigated. The aim of this study was to evaluate the role of the type 2 cannabinoid receptor (Cnr2) in regulating susceptibility to osteoarthritis in mice. We analysed the severity of knee osteoarthritis as assessed by the Osteoarthritis Research Society International (OARSI) scoring system in mice with targeted deletion of Cnr2 (Cnr2(-/-)) and wild type (WT) littermates. Studies were conducted in mice subjected to surgical destabilisation of the medial meniscus (DMM) and in those with spontaneous age-related osteoarthritis (OA). Osteoarthritis was more severe following DMM in the medial compartment of the knee in Cnr2(-/-) compared with WT mice (mean ± sem score = 4.9 ± 0.5 vs 3.6 ± 0.3; P = 0.017). Treatment of WT mice with the CB2-selective agonist HU308 following DMM reduced the severity of OA in the whole joint (HU308 = 8.4 ± 0.2 vs vehicle = 10.4 ± 0.6; P = 0.007). Spontaneous age related osteoarthritis was also more severe in the medial compartment of the knee in 12-month old Cnr2(-/-) mice compared with WT (5.6 ± 0.5 vs 3.5 ± 0.3, P = 0.008). Cultured articular chondrocytes from Cnr2(-/-) mice produced less proteoglycans in vitro than wild type chondrocytes. These studies demonstrate that the Cnr2 pathway plays a role in the pathophysiology of osteoarthritis in mice and shows that pharmacological activation of CB2 has a protective effect. Further studies of the role of cannabinoid receptors in the pathogenesis of osteoarthritis in man are warranted. Copyright © 2015 Osteoarthritis Research Society International. Published by Elsevier Ltd. All rights reserved.

  15. Interacting cannabinoid and opioid receptors in the nucleus accumbens core control adolescent social play

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    Antonia Manduca

    2016-11-01

    Full Text Available Social play behavior is a highly rewarding, developmentally important form of social interaction in young mammals. However, its neurobiological underpinnings remain incompletely understood. Previous work has suggested that opioid and endocannabinoid neurotransmission interact in the modulation of social play. Therefore, we combined behavioral, pharmacological, electrophysiological and genetic approaches to elucidate the role of the endocannabinoid 2-arachidonoylglycerol (2-AG in social play, and how cannabinoid and opioid neurotransmission interact to control social behavior in adolescent rodents. Systemic administration of the 2-AG hydrolysis inhibitor JZL184 or the opioid receptor agonist morphine increased social play behavior in adolescent rats. These effects were blocked by systemic pretreatment with either CB1 cannabinoid receptor (CB1R or mu-opioid receptor (MOR antagonists. The social play-enhancing effects of systemic morphine or JZL184 treatment were also prevented by direct infusion of the CB1R antagonist SR141716 and the MOR antagonist naloxone into the nucleus accumbens core (NAcC. Searching for synaptic correlates of these effects in adolescent NAcC excitatory synapses, we observed that CB1R antagonism blocked the effect of the MOR agonist DAMGO and, conversely, that naloxone reduced the effect of a cannabinoid agonist. These results were recapitulated in mice, and completely abolished in CB1R and MOR knockout mice, suggesting that the functional interaction between CB1R and MOR in the NAcC in the modulation of mediates social behavior is widespread in rodents. The data shed new light on the mechanism by which endocannabinoid lipids and opioid peptides interact to orchestrate rodent socioemotional behaviors.

  16. The cannabinoid-1 receptor is abundantly expressed in striatal striosomes and striosome-dendron bouquets of the substantia nigra.

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    Margaret I Davis

    Full Text Available Presynaptic cannabinoid-1 receptors (CB1-R bind endogenous and exogenous cannabinoids to modulate neurotransmitter release. CB1-Rs are expressed throughout the basal ganglia, including striatum and substantia nigra, where they play a role in learning and control of motivated actions. However, the pattern of CB1-R expression across different striatal compartments, microcircuits and efferent targets, and the contribution of different CB1-R-expressing neurons to this pattern, are unclear. We use a combination of conventional techniques and novel genetic models to evaluate CB1-R expression in striosome (patch and matrix compartments of the striatum, and in nigral targets of striatal medium spiny projection neurons (MSNs. CB1-R protein and mRNA follow a descending dorsolateral-to-ventromedial intensity gradient in the caudal striatum, with elevated expression in striosomes relative to the surrounding matrix. The lateral predominance of striosome CB1-Rs contrasts with that of the classical striosomal marker, the mu opioid receptor (MOR, which is expressed most prominently in rostromedial striosomes. The dorsolateral-to-ventromedial CB1-R gradient is similar to Drd2 dopamine receptor immunoreactivity and opposite to Substance P. This topology of CB1-R expression is maintained downstream in the globus pallidus and substantia nigra. Dense CB1-R-expressing striatonigral fibers extend dorsally within the substantia nigra pars reticulata, and colocalize with bundles of ventrally extending, striosome-targeted, dendrites of dopamine-containing neurons in the substantia nigra pars compacta (striosome-dendron bouquets. Within striatum, CB1-Rs colocalize with fluorescently labeled MSN collaterals within the striosomes. Cre recombinase-mediated deletion of CB1-Rs from cortical projection neurons or MSNs, and MSN-selective reintroduction of CB1-Rs in knockout mice, demonstrate that the principal source of CB1-Rs in dorsolateral striosomes is local MSN collaterals

  17. Immunohistochemistry detected and localized cannabinoid receptor type 2 in bovine fetal pancreas at late gestation

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    Cecilia Dall'Aglio

    2017-03-01

    Full Text Available At present, data on the endocannabinoid system expression and distribution in the pancreatic gland appear scarce and controversial as descriptions are limited to humans and laboratory animals. Since the bovine pancreas is very similar to the human in endocrine portion development and control, studies on the fetal gland could prove to be very interesting, as an abnormal maternal condition during late pregnancy may be a predisposing trigger for adult metabolic disorders. The present investigation studied cannabinoid receptor type 2 presence and distribution in the bovine fetal pancreas towards the end of gestation. Histological analyses revealed numerous endocrinal cell clusters or islets which were distributed among exocrine adenomeri in connectival tissue. Immunohistochemistry showed that endocrine-islets contained some CB2-positive cells with a very peculiar localization that is a few primarily localized at the edges of islets and some of them also scattered in the center of the cluster. Characteristically, also the epithelium of the excretory ducts and the smooth muscle layers of the smaller arteries, in the interlobular glandular septa, tested positive for the CB2 endocannabinoid receptor. Conse - quently, the endocannabinoid system, via the cannabinoid receptor type 2, was hypothesized to play a major role in controlling pancreas function from normal fetal development to correct metabolic functioning in adulthood.

  18. 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.

  19. Oxidative stress and cannabinoid receptor expression in type-2 diabetic rat pancreas following treatment with Δ⁹-THC.

    Science.gov (United States)

    Coskun, Zeynep Mine; Bolkent, Sema

    2014-10-01

    The objectives of study were (a) to determine alteration of feeding, glucose level and oxidative stress and (b) to investigate expression and localization of cannabinoid receptors in type-2 diabetic rat pancreas treated with Δ(9)-tetrahydrocannabinol (Δ(9)-THC). Rats were randomly divided into four groups: control, Δ(9)-THC, diabetes and diabetes + Δ(9)-THC groups. Diabetic rats were treated with a single dose of nicotinamide (85 mg/kg) 15 min before injection of streptozotocin (65 mg/kg). Δ(9)-THC was administered intraperitoneally at 3 mg/kg/day for 7 days. Body weights and blood glucose level of rats in all groups were measured on days 0, 7, 14 and 21. On day 15 after the Δ(9)-THC injections, pancreatic tissues were removed. Blood glucose levels and body weights of diabetic rats treated with Δ(9)-THC did not show statistically significant changes when compared with the diabetic animals on days 7, 14 and 21. Treatment with Δ(9)-THC significantly increased pancreas glutathione levels, enzyme activities of superoxide dismutase and catalase in diabetes compared with non-treatment diabetes group. The cannabinoid 1 receptor was found in islets, whereas the cannabinoid 2 receptor was found in pancreatic ducts. Their localization in cells was both nuclear and cytoplasmic. We can suggest that Δ(9) -THC may be an important agent for the treatment of oxidative damages induced by diabetes. However, it must be supported with anti-hyperglycaemic agents. Furthermore, the present study for the first time emphasizes that Δ(9)-THC may improve pancreatic cells via cannabinoid receptors in diabetes. The aim of present study was to elucidate the effects of Δ(9)-THC, a natural cannabinoid receptor agonist, on the expression and localization of cannabinoid receptors, and oxidative stress statue in type-2 diabetic rat pancreas. Results demonstrate that the cannabinoid receptors are presented in both Langerhans islets and duct regions. The curative effects

  20. The anabolic steroid nandrolone alters cannabinoid self-administration and brain CB1 receptor density and function.

    Science.gov (United States)

    Struik, Dicky; Fadda, Paola; Zara, Tamara; Zamberletti, Erica; Rubino, Tiziana; Parolaro, Daniela; Fratta, Walter; Fattore, Liana

    2017-01-01

    Clinical and pre-clinical observations indicate that anabolic-androgenic steroids can induce neurobiological changes that alter the rewarding effects of drugs of abuse. In this study, we investigated the effect of the anabolic steroid nandrolone on the rewarding properties of the cannabinoid CB 1 receptor agonist WIN55,212-2 (WIN) in rats. Lister Hooded male rats were treated intramuscularly with nandrolone (15mg/kg) or vehicle for 14 consecutive days, and then allowed to self-administer WIN (12.5μg/kg/infusion) intravenously. After reaching stable drug intake, self-administration behavior was extinguished to examine drug- and cue-induced reinstatement of cannabinoid-seeking behavior. Other behavioral parameters presumed to influence drug-taking and drug-seeking behaviors were examined to gain more insight into the behavioral specificity of nandrolone treatment. Finally, animals were sacrificed for analysis of CB 1 receptor density and function in selected brain areas. We found that nandrolone-treated rats self-administered up to 2 times more cannabinoid than vehicle-treated rats, but behaved similarly to control rats when tested for drug- and cue-induced reinstatement of cannabinoid-seeking behavior. Enhanced cannabinoid intake by nandrolone-treated rats was not accompanied by changes in locomotor activity, sensorimotor gating, or memory function. However, our molecular data show that after chronic WIN self-administration nandrolone-treated rats display altered CB 1 receptor density and function in selected brain areas. We hypothesize that increased cannabinoid self-administration in nandrolone-treated rats results from a nandrolone-induced decrease in reward function, which rats seem to compensate by voluntarily increasing their cannabinoid intake. Altogether, our findings corroborate the hypothesis that chronic exposure to anabolic-androgenic steroids induces dysfunction of the reward pathway in rats and might represent a potential risk factor for abuse of

  1. Clinical Significance of Cannabinoid Receptors CB1 and CB2 Expression in Human Malignant and Benign Thyroid Lesions

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    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.

  2. Binding and Signaling Studies Disclose a Potential Allosteric Site for Cannabidiol in Cannabinoid CB2 Receptors

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    Eva Martínez-Pinilla

    2017-10-01

    Full Text Available The mechanism of action of cannabidiol (CBD, the main non-psychotropic component of Cannabis sativa L., is not completely understood. First assumed that the compound was acting via cannabinoid CB2 receptors (CB2Rs it is now suggested that it interacts with non-cannabinoid G-protein-coupled receptors (GPCRs; however, CBD does not bind with high affinity to the orthosteric site of any GPCR. To search for alternative explanations, we tested CBD as a potential allosteric ligand of CB2R. Radioligand and non-radioactive homogeneous binding, intracellular cAMP determination and ERK1/2 phosphorylation assays were undertaken in heterologous systems expressing the human version of CB2R. Using membrane preparations from CB2R-expressing HEK-293T (human embryonic kidney 293T cells, we confirmed that CBD does not bind with high affinity to the orthosteric site of the human CB2R where the synthetic cannabinoid, [3H]-WIN 55,212-2, binds. CBD was, however, able to produce minor but consistent reduction in the homogeneous binding assays in living cells using the fluorophore-conjugated CB2R-selective compound, CM-157. The effect on binding to CB2R-expressing living cells was different to that exerted by the orthosteric antagonist, SR144528, which decreased the maximum binding without changing the KD. CBD at nanomolar concentrations was also able to significantly reduce the effect of the selective CB2R agonist, JWH133, on forskolin-induced intracellular cAMP levels and on activation of the MAP kinase pathway. These results may help to understand CBD mode of action and may serve to revisit its therapeutic possibilities.

  3. Binding and Signaling Studies Disclose a Potential Allosteric Site for Cannabidiol in Cannabinoid CB2 Receptors.

    Science.gov (United States)

    Martínez-Pinilla, Eva; Varani, Katia; Reyes-Resina, Irene; Angelats, Edgar; Vincenzi, Fabrizio; Ferreiro-Vera, Carlos; Oyarzabal, Julen; Canela, Enric I; Lanciego, José L; Nadal, Xavier; Navarro, Gemma; Borea, Pier Andrea; Franco, Rafael

    2017-01-01

    The mechanism of action of cannabidiol (CBD), the main non-psychotropic component of Cannabis sativa L., is not completely understood. First assumed that the compound was acting via cannabinoid CB 2 receptors (CB 2 Rs) it is now suggested that it interacts with non-cannabinoid G-protein-coupled receptors (GPCRs); however, CBD does not bind with high affinity to the orthosteric site of any GPCR. To search for alternative explanations, we tested CBD as a potential allosteric ligand of CB 2 R. Radioligand and non-radioactive homogeneous binding, intracellular cAMP determination and ERK1/2 phosphorylation assays were undertaken in heterologous systems expressing the human version of CB 2 R. Using membrane preparations from CB 2 R-expressing HEK-293T (human embryonic kidney 293T) cells, we confirmed that CBD does not bind with high affinity to the orthosteric site of the human CB 2 R where the synthetic cannabinoid, [ 3 H]-WIN 55,212-2, binds. CBD was, however, able to produce minor but consistent reduction in the homogeneous binding assays in living cells using the fluorophore-conjugated CB 2 R-selective compound, CM-157. The effect on binding to CB 2 R-expressing living cells was different to that exerted by the orthosteric antagonist, SR144528, which decreased the maximum binding without changing the K D . CBD at nanomolar concentrations was also able to significantly reduce the effect of the selective CB 2 R agonist, JWH133, on forskolin-induced intracellular cAMP levels and on activation of the MAP kinase pathway. These results may help to understand CBD mode of action and may serve to revisit its therapeutic possibilities.

  4. Impact of cannabis, cannabinoids and endocannabinoids in the lungs

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    Caroline Turcotte

    2016-09-01

    Full Text Available Since the identification of cannabinoid receptors in the 1990s, a research field has been dedicated to exploring the role of the cannabinoid system in immunity and the inflammatory response in human tissues and animal models. Although the cannabinoid system is present and crucial in many human tissues, studying the impact of cannabinoids on the lungs is particularly relevant because of their contact with exogenous cannabinoids is the context of marijuana consumption. In the past two decades, the scientific community has gathered a large body of evidence supporting that the activation of the cannabinoid system alleviates pain and reduces inflammation. In the context of lung inflammation, exogenous and endogenous cannabinoids have shown therapeutic potential because of their inhibitory effects on immune cell recruitment and functions. On the other hand, cannabinoids were shown to be deleterious to lung function and to impact respiratory pathogen clearance. In this review, we present the existing data on the regulation of lung immunity and inflammation by phytocannabinoids, synthetic cannabinoids and endocannabinoids.

  5. 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.

  6. The cannabinoid receptor type 2 as mediator of mesenchymal stromal cell immunosuppressive properties.

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    Francesca Rossi

    Full Text Available Mesenchymal stromal cells are non-hematopoietic, multipotent progenitor cells producing cytokines, chemokines, and extracellular matrix proteins that support hematopoietic stem cell survival and engraftment, influence immune effector cell development, maturation, and function, and inhibit alloreactive T-cell responses. The immunosuppressive properties of human mesenchymal stromal cells have attracted much attention from immunologists, stem cell biologists and clinicians. Recently, the presence of the endocannabinoid system in hematopoietic and neural stem cells has been demonstrated. Endocannabinoids, mainly acting through the cannabinoid receptor subtype 2, are able to modulate cytokine release and to act as immunosuppressant when added to activated T lymphocytes. In the present study, we have investigated, through a multidisciplinary approach, the involvement of the endocannabinoids in migration, viability and cytokine release of human mesenchymal stromal cells. We show, for the first time, that cultures of human mesenchymal stromal cells express all of the components of the endocannabinoid system, suggesting a potential role for the cannabinoid CB2 receptor as a mediator of anti-inflammatory properties of human mesenchymal stromal cells, as well as of their survival pathways and their capability to home and migrate towards endocannabinoid sources.

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

    International Nuclear Information System (INIS)

    Jäntti, Maria H.; Mandrika, Ilona; Kukkonen, Jyrki P.

    2014-01-01

    Highlights: • OX 1 and OX 2 orexin and CB 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 1 orexin receptors have been shown to homodimerize and they have also been suggested to heterodimerize with CB 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 1 , OX 2 and CB 1 receptors, C-terminally fused with either Renilla luciferase or GFP 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 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 2 to CB 1 produced more effective BRET than the opposite fusions, also suggesting differences in geometry. Similar was seen for the OX 1 –OX 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 1 receptors, dimerization could be an effective way of forming signal complexes with optimal cannabinoid concentrations

  8. Regulation of Hippocampal Cannabinoid CB1 Receptor Actions by Adenosine A1 Receptors and Chronic Caffeine Administration: Implications for the Effects of Δ9-Tetrahydrocannabinol on Spatial Memory

    OpenAIRE

    Sousa, Vasco C; Assaife-Lopes, Natália; Ribeiro, Joaquim A; Pratt, Judith A; Brett, Ros R; Sebastião, Ana M

    2010-01-01

    Abstract The cannabinoid CB1 receptor-mediated modulation of ?-aminobutyric acid (GABA) release from inhibitory interneurons is important for the integrity of hippocampal-dependent spatial memory. Although adenosine A1 receptors have a central role in fine-tuning excitatory transmission in the hippocampus, A1 receptors localized in GABAergic cells do not directly influence GABA release. CB1 and A1 receptors are the main targets for the effects of two of the most heavily consumed ps...

  9. Effects of caffeine on striatal neurotransmission: focus on cannabinoid CB1 receptors.

    Science.gov (United States)

    Rossi, Silvia; De Chiara, Valentina; Musella, Alessandra; Mataluni, Giorgia; Sacchetti, Lucia; Siracusano, Alberto; Bernardi, Giorgio; Usiello, Alessandro; Centonze, Diego

    2010-04-01

    Caffeine is the most commonly self-administered psychoactive substance worldwide. At usual doses, the effects of caffeine on vigilance, attention, mood and arousal largely depend on the modulation of central adenosine receptors. The present review article describes the action of caffeine within the striatum, to provide a possible molecular mechanism at the basis of the psychomotor and reinforcing properties of this pharmacological agent. The striatum is in fact a subcortical area involved in sensorimotor, cognitive, and emotional processes, and recent experimental findings showed that chronic caffeine consumption enhances the sensitivity of striatal GABAergic synapses to the stimulation of cannabinoid CB1 receptors. The endocannabinoid system is involved in the psychoactive effects of many compounds, and adenosine A2A receptors (the main receptor target of caffeine) elicit a permissive effect towards CB1 receptors, thus suggesting that A2A-CB1 receptor interaction plays a major role in the generation and maintenance of caffeine reinforcing behavior. Aim of this review is to describe the effects of caffeine on striatal neurotransmission with special reference to the modulation of the endocannabinoid system.

  10. METHODS FOR RECOMBINANT EXPRESSION AND FUNCTIONAL CHARACTERIZATION OF HUMAN CANNABINOID RECEPTOR CB2

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    Alexei A. Yeliseev

    2013-03-01

    Full Text Available Cannabinoid receptor CB2 is a seven transmembrane-domain integral membrane protein that belongs to a large superfamily of G protein-coupled receptors (GPCR. CB2 is a part of the endocannabinoid system that plays vital role in regulation of immune response, inflammation, pain sensitivity, obesity and other physiological responses. Information about the structure and mechanisms of functioning of this receptor in cell membranes is essential for the rational development of specific pharmaceuticals. Here we review the methodology for recombinant expression, purification, stabilization and biochemical characterization of CB2 suitable for preparation of multi-milligram quantities of functionally active receptor. The biotechnological protocols include expression of the recombinant CB2 in E. coli cells as a fusion with the maltose binding protein, stabilization with a high affinity ligand and a derivative of cholesterol in detergent micelles, efficient purification by tandem affinity chromatography, and reconstitution of the receptor into lipid bilayers. The purified recombinant CB2 receptor is amenable to functional and structural studies including nuclear magnetic resonance spectroscopy and a wide range of biochemical and biophysical techniques.

  11. Role of hypothalamic cannabinoid receptors in post-stroke depression in rats.

    Science.gov (United States)

    Wang, Shanshan; Sun, Hong; Liu, Sainan; Wang, Ting; Guan, Jinqun; Jia, Jianjun

    2016-03-01

    One of the most common psychological consequences of stroke is post-stroke depression (PSD). While more than 30 percent of stroke patients eventually develop PSD, the neurobiological mechanisms underlying such a phenomenon have not been well investigated. Given the critical involvement of hypothalamic-pituitary-adrenal axis and endocannabinoid system in response to stressful stimuli, we evaluated the hypothesis that cannabinoid receptors in the hypothalamus are critical for modulation of post-stroke depression-like behaviors in rats. To this end, rats were treated with middle cerebral artery occlusion (MCAO) followed by chronic unpredictable mild stress (CUMS) treatment procedure. We then assessed the expression of CB1 and CB2 receptors in the hypothalamus, and evaluated the effects of pharmacological stimulations of CB1 or CB2 receptors on the expression and development of depression-like behaviors in PSD rats. We found that PSD rats exhibited decreased the expression of CB1 receptor, but not CB2 receptor, in the ventral medial hypothalamus (VMH). Such an effect was not observed in the dorsally adjacent brain regions. Furthermore, intra-VMH injections of CB2 receptor agonist, but not CB1 receptor agonist, attenuated the expression of depression-like behaviors in PSD rats. Finally, repeated intraperitoneal injections of CB1 or CB2 receptor agonists during CUMS treatment inhibited the development of depression-like behaviors in PSD rats. Taken together, these results suggest that decreased CB1 receptor expression is likely associated with the development of post-stroke depression, and CB2 receptor may be a potential therapeutic target for the treatment post-stroke depressive disorders. Copyright © 2016 Elsevier Inc. All rights reserved.

  12. Effects of cannabinoid and glutamate receptor antagonists and their interactions on learning and memory in male rats.

    Science.gov (United States)

    Barzegar, Somayeh; Komaki, Alireza; Shahidi, Siamak; Sarihi, Abdolrahman; Mirazi, Naser; Salehi, Iraj

    2015-04-01

    Despite previous findings on the effects of cannabinoid and glutamatergic systems on learning and memory, the effects of the combined stimulation or the simultaneous inactivation of these two systems on learning and memory have not been studied. In addition, it is not clear whether the effects of the cannabinoid system on learning and memory occur through the modulation of glutamatergic synaptic transmission. Hence, in this study, we examined the effects of the simultaneous inactivation of the cannabinoid and glutamatergic systems on learning and memory using a passive avoidance (PA) test in rats. On the test day, AM251, which is a CB1 cannabinoid receptor antagonist; MK-801, which is a glutamate receptor antagonist; or both substances were injected intraperitoneally into male Wistar rats 30min before placing the animal in a shuttle box. A learning test (acquisition) was then performed, and a retrieval test was performed the following day. Learning and memory in the PA test were significantly different among the groups. The CB1 receptor antagonist improved the scores on the PA acquisition and retention tests. However, the glutamatergic receptor antagonist decreased the acquisition and retrieval scores on the PA task. The CB1 receptor antagonist partly decreased the glutamatergic receptor antagonist effects on PA learning and memory. These results indicated that the acute administration of a CB1 antagonist improved cognitive performance on a PA task in normal rats and that a glutamate-related mechanism may underlie the antagonism of cannabinoid by AM251 in learning and memory. Copyright © 2015 Elsevier Inc. All rights reserved.

  13. 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

  14. Role of endocannabinoids and cannabinoid-1 receptors in cerebrocortical blood flow regulation.

    Directory of Open Access Journals (Sweden)

    András Iring

    Full Text Available Endocannabinoids are among the most intensively studied lipid mediators of cardiovascular functions. In the present study the effects of decreased and increased activity of the endocannabinoid system (achieved by cannabinoid-1 (CB1 receptor blockade and inhibition of cannabinoid reuptake, respectively on the systemic and cerebral circulation were analyzed under steady-state physiological conditions and during hypoxia and hypercapnia (H/H.In anesthetized spontaneously ventilating rats the CB1-receptor antagonist/inverse agonist AM-251 (10 mg/kg, i.v. failed to influence blood pressure (BP, cerebrocortical blood flow (CoBF, measured by laser-Doppler flowmetry or arterial blood gas levels. In contrast, the putative cannabinoid reuptake inhibitor AM-404 (10 mg/kg, i.v. induced triphasic responses, some of which could be blocked by AM-251. Hypertension during phase I was resistant to AM-251, whereas the concomitant CoBF-increase was attenuated. In contrast, hypotension during phase III was sensitive to AM-251, whereas the concomitant CoBF-decrease was not. Therefore, CoBF autoregulation appeared to shift towards higher BP levels after CB1-blockade. During phase II H/H developed due to respiratory depression, which could be inhibited by AM-251. Interestingly, however, the concomitant rise in CoBF remained unchanged after AM-251, indicating that CB1-blockade potentially enhanced the reactivity of the CoBF to H/H. In accordance with this hypothesis, AM-251 induced a significant enhancement of the CoBF responses during controlled stepwise H/H.Under resting physiological conditions CB1-receptor mediated mechanisms appear to have limited influence on systemic or cerebral circulation. Enhancement of endocannabinoid levels, however, induces transient CB1-independent hypertension and sustained CB1-mediated hypotension. Furthermore, enhanced endocannabinoid activity results in respiratory depression in a CB1-dependent manner. Finally, our data indicate for the

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

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    Ahmed Haider

    2016-07-01

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

  16. Orexin Receptor Multimerization versus Functional Interactions: Neuropharmacological Implications for Opioid and Cannabinoid Signalling and Pharmacogenetics

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    Miles D. Thompson

    2017-10-01

    Full Text Available Orexins/hypocretins are neuropeptides formed by proteolytic cleavage of a precursor peptide, which are produced by neurons found in the lateral hypothalamus. The G protein-coupled receptors (GPCRs for these ligands, the OX1 and OX2 orexin receptors, are more widely expressed throughout the central nervous system. The orexin/hypocretin system has been implicated in many pathways, and its dysregulation is under investigation in a number of diseases. Disorders in which orexinergic mechanisms are being investigated include narcolepsy, idiopathic sleep disorders, cluster headache and migraine. Human narcolepsy has been associated with orexin deficiency; however, it has only rarely been attributed to mutations in the gene encoding the precursor peptide. While gene variations within the canine OX2 gene hcrtr2 have been directly linked with narcolepsy, the majority of human orexin receptor variants are weakly associated with diseases (the idiopathic sleep disorders, cluster headache and polydipsia-hyponatremia in schizophrenia or are of potential pharmacogenetic significance. Evidence for functional and/or heterodimerization between wild-type variant orexin receptors and opioid and cannabinoid receptors is discussed in the context of its relevance to depression and epilepsy.

  17. Selective Cannabinoid 2 Receptor Stimulation Reduces Tubular Epithelial Cell Damage after Renal Ischemia-Reperfusion Injury.

    Science.gov (United States)

    Pressly, Jeffrey D; Mustafa, Suni M; Adibi, Ammaar H; Alghamdi, Sahar; Pandey, Pankaj; Roy, Kuldeep K; Doerksen, Robert J; Moore, Bob M; Park, Frank

    2018-02-01

    Ischemia-reperfusion injury (IRI) is a common cause of acute kidney injury (AKI), which is an increasing problem in the clinic and has been associated with elevated rates of mortality. Therapies to treat AKI are currently not available, so identification of new targets that can be modulated to ameliorate renal damage upon diagnosis of AKI is essential. In this study, a novel cannabinoid receptor 2 (CB2) agonist, SMM-295 [3'-methyl-4-(2-(thiophen-2-yl)propan-2-yl)biphenyl-2,6-diol], was designed, synthesized, and tested in vitro and in silico. Molecular docking of SMM-295 into a CB2 active-state homology model showed that SMM-295 interacts well with key amino acids to stabilize the active state. In human embryonic kidney 293 cells, SMM-295 was capable of reducing cAMP production with 66-fold selectivity for CB2 versus cannabinoid receptor 1 and dose-dependently increased mitogen-activated protein kinase and Akt phosphorylation. In vivo testing of the CB2 agonist was performed using a mouse model of bilateral IRI, which is a common model to mimic human AKI, where SMM-295 was immediately administered upon reperfusion of the kidneys after the ischemia episode. Histologic damage assessment 48 hours after reperfusion demonstrated reduced tubular damage in the presence of SMM-295. This was consistent with reduced plasma markers of renal dysfunction (i.e., creatinine and neutrophil gelatinase-associated lipocalin) in SMM-295-treated mice. Mechanistically, kidneys treated with SMM-295 were shown to have elevated activation of Akt with reduced terminal deoxynucleotidyl transferase-mediated digoxigenin-deoxyuridine nick-end labeling (TUNEL)-positive cells compared with vehicle-treated kidneys after IRI. These data suggest that selective CB2 receptor activation could be a potential therapeutic target in the treatment of AKI. Copyright © 2018 by The American Society for Pharmacology and Experimental Therapeutics.

  18. THE CANNABINOID RECEPTOR ANTAGONIST AM251 INCREASES PARAOXON AND CHLORPYRIFOS OXON TOXICITY IN RATS

    Science.gov (United States)

    Liu, Jing; Pope, Carey

    2014-01-01

    Organophosphorus anticholinesterases (OPs) elicit acute toxicity by inhibiting acetylcholinesterase (AChE), leading to acetylcholine accumulation and overstimulation of cholinergic receptors. Endocannabinoids (eCBs, e.g., arachidonoyl ethanolamide [AEA] and 2-arachidonoyl glycerol [2-AG]) are neuromodulators that regulate neurotransmission by reducing neurotransmitter release. The eCBs are degraded by the enzymes fatty acid amide hydrolase (FAAH, primarily involved in hydrolysis of AEA) and monoacylglycerol lipase (MAGL, primarily responsible for metabolism of 2-AG). We previously reported that the cannabinoid receptor agonist WIN 55,212-2 reduced cholinergic toxicity after paraoxon exposure. This study compared the effects of the cannabinoid receptor antagonist AM251 on acute toxicity following either paraoxon (PO) or chlorpyrifos oxon (CPO). CPO was more potent in vitro than PO at inhibiting AChE (≈ 2 fold), FAAH (≈ 8 fold), and MAGL (≈ 19 fold). Rats were treated with vehicle, PO (0.3 and 0.6 mg/kg, sc.) or CPO (6 and 12 mg/kg, sc.) and subsets treated with AM251 (3 mg/kg, ip; 30 min after OP). Signs of toxicity were recorded for four hours and rats were then sacrificed. OP-treated rats showed dose-related involuntary movements, with AM251 increasing signs of toxicity with the lower dosages. PO and CPO elicited excessive secretions, but AM251 had no apparent effect with either OP. Lethality was increased by AM251 with the higher dosage of PO, but no lethality was noted with either dosage of CPO, with or without AM251. Both OPs caused extensive inhibition of hippocampal AChE and FAAH (>80–90%), but only CPO inhibited MAGL (37–50%). These results provide further evidence that eCB signaling can influence acute OP toxicity. The selective in vivo inhibition of MAGL by CPO may be important in the differential lethality noted between PO and CPO with AM251 co-administration. PMID:25447325

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

    International Nuclear Information System (INIS)

    Baireddy, Praveena; Liu, Jing; Hinsdale, Myron; Pope, Carey

    2011-01-01

    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 μM) 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: ► C57Bl/6 mice showed dose-related cholinergic toxicity following subcutaneous chlorpyrifos exposure. ► Wild type and cannabinoid CB1 receptor knockout littermates

  20. 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

  1. Cannabinoid Receptor 1 Gene Polymorphisms and Marijuana Misuse Interactions On White Matter and Cognitive Deficits in Schizophrenia

    OpenAIRE

    Ho, Beng-Choon; Wassink, Thomas H.; Ziebell, Steven; Andreasen, Nancy C.

    2011-01-01

    Marijuana exposure during the critical period of adolescent brain maturation may disrupt neuro-modulatory influences of endocannabinoids and increase schizophrenia susceptibility. Cannabinoid receptor 1 (CB1/CNR1) is the principal brain receptor mediating marijuana effects. No study to-date has systematically investigated the impact of CNR1 on quantitative phenotypic features in schizophrenia and inter-relationships with marijuana misuse. We genotyped 235 schizophrenia patients using 12 tag s...

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

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    Pedro Reis Rodrigues

    2016-06-01

    Full Text Available 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.

  3. Cannabinoid receptor-2 immunoreactivity is associated with survival in squamous cell carcinoma of the head and neck.

    Science.gov (United States)

    Klein Nulent, Thomas J W; Van Diest, Paul J; van der Groep, Petra; Leusink, Frank K J; Kruitwagen, Cas L J J; Koole, Ronald; Van Cann, Ellen M

    2013-10-01

    The prediction of progression of individual tumours, prognosis, and survival in squamous cell carcinoma (SCC) of the head and neck is difficult. Cannabinoid-1 (CB1) and cannabinoid-2 (CB2) receptor expression is related to survival in several types of cancer, and the aim of this study was to find out whether the expression of CB1 and CB2 receptors is associated with survival in primary SCC of the head and neck. We made immunohistochemical analyses of the cannabinoid receptors on tissue arrays from 240 patients with the disease. Receptor immunoreactivity was classified as none, weak, moderate, or strong staining. Overall survival and disease-specific survival were plotted using Kaplan-Meier survival curves. A multivariate Cox proportional hazard model was created with all the relevant clinical and pathological features. Strong immunoreactivity of the CB2 receptor was significantly associated with reduced disease-specific survival (p=0.007). Cox-proportional hazard ratio (HR) showed that CB2 receptor immunoreactivity contributed to the prediction of survival (HR 3.6, 95% CI 1.5-8.7, p=0.004). Depth of invasion (HR 2.2, 95% CI 1.2-4.2, p=0.01) and vascular invasion (HR 2.5, 95% CI 1.4-4.5, p=0.001) were also associated with survival. Copyright © 2013 The British Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.

  4. Role of CB1 cannabinoid receptors on GABAergic neurons in brain aging.

    Science.gov (United States)

    Albayram, Onder; Alferink, Judith; Pitsch, Julika; Piyanova, Anastasia; Neitzert, Kim; Poppensieker, Karola; Mauer, Daniela; Michel, Kerstin; Legler, Anne; Becker, Albert; Monory, Krisztina; Lutz, Beat; Zimmer, Andreas; Bilkei-Gorzo, Andras

    2011-07-05

    Brain aging is associated with cognitive decline that is accompanied by progressive neuroinflammatory changes. The endocannabinoid system (ECS) is involved in the regulation of glial activity and influences the progression of age-related learning and memory deficits. Mice lacking the Cnr1 gene (Cnr1(-/-)), which encodes the cannabinoid receptor 1 (CB1), showed an accelerated age-dependent deficit in spatial learning accompanied by a loss of principal neurons in the hippocampus. The age-dependent decrease in neuronal numbers in Cnr1(-/-) mice was not related to decreased neurogenesis or to epileptic seizures. However, enhanced neuroinflammation characterized by an increased density of astrocytes and activated microglia as well as an enhanced expression of the inflammatory cytokine IL-6 during aging was present in the hippocampus of Cnr1(-/-) mice. The ongoing process of pyramidal cell degeneration and neuroinflammation can exacerbate each other and both contribute to the cognitive deficits. Deletion of CB1 receptors from the forebrain GABAergic, but not from the glutamatergic neurons, led to a similar neuronal loss and increased neuroinflammation in the hippocampus as observed in animals lacking CB1 receptors in all cells. Our results suggest that CB1 receptor activity on hippocampal GABAergic neurons protects against age-dependent cognitive decline by reducing pyramidal cell degeneration and neuroinflammation.

  5. Electroacupuncture Potentiates Cannabinoid Receptor-Mediated Descending Inhibitory Control in a Mouse Model of Knee Osteoarthritis

    Directory of Open Access Journals (Sweden)

    Xiao-Cui Yuan

    2018-04-01

    Full Text Available Knee osteoarthritis (KOA is a highly prevalent, chronic joint disorder, which can lead to chronic pain. Although electroacupuncture (EA is effective in relieving chronic pain in the clinic, the involved mechanisms remain unclear. Reduced diffuse noxius inhibitory controls (DNIC function is associated with chronic pain and may be related to the action of endocannabinoids. In the present study, we determined whether EA may potentiate cannabinoid receptor-mediated descending inhibitory control and inhibit chronic pain in a mouse model of KOA. We found that the optimized parameters of EA inhibiting chronic pain were the low frequency and high intensity (2 Hz + 1 mA. EA reversed the reduced expression of CB1 receptors and the 2-arachidonoylglycerol (2-AG level in the midbrain in chronic pain. Microinjection of the CB1 receptor antagonist AM251 into the ventrolateral periaqueductal gray (vlPAG can reversed the EA effect on pain hypersensitivity and DNIC function. In addition, CB1 receptors on GABAergic but not glutamatergic neurons are involved in the EA effect on DNIC function and descending inhibitory control of 5-HT in the medulla, thus inhibiting chronic pain. Our data suggest that endocannabinoid (2-AG-CB1R-GABA-5-HT may be a novel signaling pathway involved in the effect of EA improving DNIC function and inhibiting chronic pain.

  6. Cannabinoid CB2 receptor potentiates obesity-associated inflammation, insulin resistance and hepatic steatosis.

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    Vanessa Deveaux

    Full Text Available BACKGROUND: Obesity-associated inflammation is of critical importance in the development of insulin resistance and non-alcoholic fatty liver disease. Since the cannabinoid receptor CB2 regulates innate immunity, the aim of the present study was to investigate its role in obesity-induced inflammation, insulin resistance and fatty liver. METHODOLOGY: Murine obesity models included genetically leptin-deficient ob/ob mice and wild type (WT mice fed a high fat diet (HFD, that were compared to their lean counterparts. Animals were treated with pharmacological modulators of CB2 receptors. Experiments were also performed in mice knock-out for CB2 receptors (Cnr2 -/-. PRINCIPAL FINDINGS: In both HFD-fed WT mice and ob/ob mice, Cnr2 expression underwent a marked induction in the stromal vascular fraction of epididymal adipose tissue that correlated with increased fat inflammation. Treatment with the CB2 agonist JWH-133 potentiated adipose tissue inflammation in HFD-fed WT mice. Moreover, cultured fat pads isolated from ob/ob mice displayed increased Tnf and Ccl2 expression upon exposure to JWH-133. In keeping, genetic or pharmacological inactivation of CB2 receptors decreased adipose tissue macrophage infiltration associated with obesity, and reduced inductions of Tnf and Ccl2 expressions. In the liver of obese mice, Cnr2 mRNA was only weakly induced, and CB2 receptors moderately contributed to liver inflammation. HFD-induced insulin resistance increased in response to JWH-133 and reduced in Cnr2 -/- mice. Finally, HFD-induced hepatic steatosis was enhanced in WT mice treated with JWH-133 and blunted in Cnr2 -/- mice. CONCLUSION/SIGNIFICANCE: These data unravel a previously unrecognized contribution of CB2 receptors to obesity-associated inflammation, insulin resistance and non-alcoholic fatty liver disease, and suggest that CB2 receptor antagonists may open a new therapeutic approach for the management of obesity-associated metabolic disorders.

  7. CB1 cannabinoid receptor expression in the striatum: Association with corticostriatal circuits and developmental regulation

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    Vincent eVan Waes

    2012-03-01

    Full Text Available Corticostriatal circuits mediate various aspects of goal-directed behavior and are critically important for basal ganglia-related disorders. Activity in these circuits is regulated by the endocannabinoid system via stimulation of CB1 cannabinoid receptors. CB1 receptors are highly expressed in projection neurons and select interneurons of the striatum, but expression levels vary considerably between different striatal regions (functional domains. We investigated CB1 receptor expression within specific corticostriatal circuits by mapping CB1 mRNA levels in striatal sectors defined by their cortical inputs in rats. We also assessed changes in CB1 expression in the striatum during development. Our results show that CB1 expression is highest in juveniles (P25 and then progressively decreases towards adolescent (P40 and adult (P70 levels. At every age, CB1 receptors are predominantly expressed in sensorimotor striatal sectors, with considerably lower expression in associative and limbic sectors. Moreover, for most corticostriatal circuits there is an inverse relationship between cortical and striatal expression levels. Thus, striatal sectors with high CB1 expression (sensorimotor sectors tend to receive inputs from cortical areas with low expression, while striatal sectors with low expression (associative/limbic sectors receive inputs from cortical regions with higher expression (medial prefrontal cortex. In so far as CB1 mRNA levels reflect receptor function, our findings suggest differential CB1 signaling between different developmental stages and between sensorimotor and associative/limbic circuits. The regional distribution of CB1 receptor expression in the striatum further suggests that, in sensorimotor sectors, CB1 receptors mostly regulate GABA inputs from local axon collaterals of projection neurons, whereas in associative/limbic sectors, CB1 regulation of GABA inputs from interneurons and glutamate inputs may be more important.

  8. Cannabinoid receptor 2 participates in amyloid-β processing in a mouse model of Alzheimer's disease but plays a minor role in the therapeutic properties of a cannabis-based medicine

    OpenAIRE

    Aso Pérez, Ester; Andrés Benito, Pol; Carmona, Margarita; Maldonado, Rafael, 1961-; Ferrer, Isidre

    2016-01-01

    The endogenous cannabinoid system represents a promising therapeutic target to modify neurodegenerative pathways linked to Alzheimer's disease (AD). The aim of the present study was to evaluate the specific contribution of CB2 receptor to the progression of AD-like pathology and its role in the positive effect of a cannabis-based medicine (1:1 combination of Δ9-tetrahidrocannabinol and cannabidiol) previously demonstrated to be beneficial in the AβPP/PS1 transgenic model of the disease. A new...

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

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    Lisa K Brents

    Full Text Available 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.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.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, combined with higher CB1R affinity and activity relative to Δ(9

  10. CB1 cannabinoid receptor-mediated anandamide signaling mechanisms of the inferior colliculus modulate the haloperidol-induced catalepsy.

    Science.gov (United States)

    Medeiros, P; de Freitas, R L; Silva, M O; Coimbra, N C; Melo-Thomas, L

    2016-11-19

    The inferior colliculus (IC), a midbrain structure that processes acoustic information of aversive nature, is distinguished from other auditory nuclei in the brainstem by its connections with structures of the motor system. Previous evidence relating the IC to motor behavior shows that glutamatergic and GABAergic mechanisms in the IC exert influence on systemic haloperidol-induced catalepsy. There is substantial evidence supporting a role played by the endocannabinoid system as a modulator of the glutamatergic neurotransmission, as well as the dopaminergic activity in the basal nuclei and therefore it may be considered as a potential pharmacological target for the treatment of movement disorders. The present study evaluated if the endocannabinoid system in the IC plays a role in the elaboration of systemic haloperidol-induced catalepsy. Male Wistar rats received intracollicular microinjection of either the endogenous cannabinoid anandamide (AEA) at different concentrations (5, 50 or 100pmol/0.2μl), the CB 1 cannabinoid receptor antagonist AM251 at 50, 100 or 200pmol/0.2μl or vehicle, followed by intraperitoneal (IP) administration of either haloperidol at 0.5 or 1mg/kg or physiological saline. Systemic injection of haloperidol at both doses (0.5 or 1mg/kg, IP) produced a cataleptic state, compared to vehicle/physiological saline-treated group, lasting 30 and 50min after systemic administration of the dopaminergic receptors non-selective antagonist. The midbrain microinjection of AEA at 50pmol/0.2μl increased the latency for stepping down from the horizontal bar after systemic administration of haloperidol. Moreover, the intracollicular administration of AEA at 50pmol/0.2μl was able to increase the duration of catalepsy as compared to AEA at 100pmol/0.2-μl-treated group. Intracollicular pretreatment with AM251 at the intermediate concentration (100pmol/0.2μl) was able to decrease the duration of catalepsy after systemic administration of haloperidol. However

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

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    Nicola H. Morgan

    2008-01-01

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

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

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    Guyllaume Coiret

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

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

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    Coiret, Guyllaume; Ster, Jeanne; Grewe, Benjamin; Wendling, Fabrice; Helmchen, Fritjof; Gerber, Urs; Benquet, Pascal

    2012-01-01

    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.

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

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    Balázs Csóka

    2009-07-01

    Full Text Available 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.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.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.

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

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    Yin Shou

    2013-01-01

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

  16. The cannabinoid receptor CB1 contributes to the development of ectopic lesions in a mouse model of endometriosis.

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    Sanchez, Ana-Maria; Quattrone, Federica; Pannese, Maria; Ulisse, Adele; Candiani, Massimo; Diaz-Alonso, Javier; Velasco, Guillermo; Panina-Bordignon, Paola

    2017-01-01

    Does signaling via the cannabinoid (CB 1 ) receptor play a role in the pathogenesis of endometriosis in a mouse model? Mice treated with a CB 1 agonist developed larger ectopic lesions, while less severe lesions developed in the absence of functional CB 1 expression. The expression of components of the endocannabinoid system has been demonstrated in both mouse and human uteri. CB 1 receptors are expressed in human epithelial and stromal cell lines derived from eutopic endometrium and deep infiltrating endometriosis nodules. This was a randomized study in a mouse model of endometriosis. In a first set of experiments, mice with endometriosis were treated with the CB 1 receptor agonist methanandamide (MET) (5 mg/kg, n = 20) on Days 1-5 and 8-12. In a second set of experiments, endometriosis development was evaluated in CB 1 -/- mice and in their wild-type (WT) littermates. Endometriosis-like lesions were induced in Balb/c and C57/Bl6 mice. Two weeks after disease induction, the lesions were counted, measured and either included for immunohistochemistry analysis or frozen for gene expression profiling by semi-quantitative real-time PCR. To limit the role of chance, the experiments were conducted under standardized laboratory conditions with appropriate controls. The lesion total volume was significantly higher in MET-treated compared with vehicle-treated mice (P endometriosis in a mouse model. However, the relative contribution of the CB 1 -mediated signaling pathways active in inflammatory, uterine and peritoneal cells remains to be ascertained. Since the study was performed in a mouse model, the significance of the findings in the human system warrants further investigation. Clarifying the function and regulation of CB 1 and its molecular interactions with endogenous ligands, and how endocannabinoids levels are regulated in women with endometriosis, represent critical areas of research for the potential development of a novel medical treatment of the disease. A

  17. Phencyclidine-induced social withdrawal results from deficient stimulation of cannabinoid CB₁ receptors: implications for schizophrenia.

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    Seillier, Alexandre; Martinez, Alex A; Giuffrida, Andrea

    2013-08-01

    The neuronal mechanisms underlying social withdrawal, one of the core negative symptoms of schizophrenia, are not well understood. Recent studies suggest an involvement of the endocannabinoid system in the pathophysiology of schizophrenia and, in particular, of negative symptoms. We used biochemical, pharmacological, and behavioral approaches to investigate the role played by the endocannabinoid system in social withdrawal induced by sub-chronic administration of phencyclidine (PCP). Pharmacological enhancement of endocannabinoid levels via systemic administration of URB597, an inhibitor of endocannabinoid degradation, reversed social withdrawal in PCP-treated rats via stimulation of CB1 receptors, but reduced social interaction in control animals through activation of a cannabinoid/vanilloid-sensitive receptor. In addition, the potent CB agonist CP55,940 reversed PCP-induced social withdrawal in a CB₁-dependent manner, whereas pharmacological blockade of CB₁ receptors by either AM251 or SR141716 reduced the time spent in social interaction in control animals. PCP-induced social withdrawal was accompanied by a decrease of anandamide (AEA) levels in the amygdala and prefrontal cortex, and these deficits were reversed by URB597. As CB₁ receptors are predominantly expressed on GABAergic interneurons containing the anxiogenic peptide cholecystokinin (CCK), we also examined whether the PCP-induced social withdrawal resulted from deficient CB₁-mediated modulation of CCK transmission. The selective CCK2 antagonist LY225910 blocked both PCP- and AM251-induced social withdrawal, but not URB597 effect in control rats. Taken together, these findings indicate that AEA-mediated activation of CB₁ receptors is crucial for social interaction, and that PCP-induced social withdrawal results from deficient endocannabinoid transmission.

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

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    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.

  19. Role of cannabinoid receptor CB2 in HER2 pro-oncogenic signaling in breast cancer.

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    Pérez-Gómez, Eduardo; Andradas, Clara; Blasco-Benito, Sandra; Caffarel, María M; García-Taboada, Elena; Villa-Morales, María; Moreno, Estefanía; Hamann, Sigrid; Martín-Villar, Ester; Flores, Juana M; Wenners, Antonia; Alkatout, Ibrahim; Klapper, Wolfram; Röcken, Christoph; Bronsert, Peter; Stickeler, Elmar; Staebler, Annette; Bauer, Maret; Arnold, Norbert; Soriano, Joaquim; Pérez-Martínez, Manuel; Megías, Diego; Moreno-Bueno, Gema; Ortega-Gutiérrez, Silvia; Artola, Marta; Vázquez-Villa, Henar; Quintanilla, Miguel; Fernández-Piqueras, José; Canela, Enric I; McCormick, Peter J; Guzmán, Manuel; Sánchez, Cristina

    2015-06-01

    Pharmacological activation of cannabinoid receptors elicits antitumoral responses in different cancer models. However, the biological role of these receptors in tumor physio-pathology is still unknown. We analyzed CB2 cannabinoid receptor protein expression in two series of 166 and 483 breast tumor samples operated in the University Hospitals of Kiel, Tübingen, and Freiburg between 1997 and 2010 and CB2 mRNA expression in previously published DNA microarray datasets. The role of CB2 in oncogenesis was studied by generating a mouse line that expresses the human V-Erb-B2 Avian Erythroblastic Leukemia Viral Oncogene Homolog 2 (HER2) rat ortholog (neu) and lacks CB2 and by a variety of biochemical and cell biology approaches in human breast cancer cells in culture and in vivo, upon modulation of CB2 expression by si/shRNAs and overexpression plasmids. CB2-HER2 molecular interaction was studied by colocalization, coimmunoprecipitation, and proximity ligation assays. Statistical tests were two-sided. We show an association between elevated CB2 expression in HER2+ breast tumors and poor patient prognosis (decreased overall survival, hazard ratio [HR] = 0.29, 95% confidence interval [CI] = 0.09 to 0.71, P = .009) and higher probability to suffer local recurrence (HR = 0.09, 95% CI = 0.049 to 0.54, P = .003) and to develop distant metastases (HR = 0.33, 95% CI = 0.13 to 0.75, P = .009). We also demonstrate that genetic inactivation of CB2 impairs tumor generation and progression in MMTV-neu mice. Moreover, we show that HER2 upregulates CB2 expression by activating the transcription factor ELK1 via the ERK cascade and that an increased CB2 expression activates the HER2 pro-oncogenic signaling at the level of the tyrosine kinase c-SRC. Finally, we show HER2 and CB2 form heteromers in cancer cells. Our findings reveal an unprecedented role of CB2 as a pivotal regulator of HER2 pro-oncogenic signaling in breast cancer, and they suggest that CB2 may be a biomarker with

  20. Preclinical evaluation of SMM-189, a cannabinoid receptor 2-specific inverse agonist.

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    Presley, Chaela; Abidi, Ammaar; Suryawanshi, Satyendra; Mustafa, Suni; Meibohm, Bernd; Moore, Bob M

    2015-08-01

    Cannabinoid receptor 2 agonists and inverse agonists are emerging as new therapeutic options for a spectrum of autoimmune-related disease. Of particular interest, is the ability of CB2 ligands to regulate microglia function in neurodegenerative diseases and traumatic brain injury. We have previously reported the receptor affinity of 3',5'-dichloro-2,6-dihydroxy-biphenyl-4-yl)-phenyl-methanone (SMM-189) and the characterization of the beneficial effects of SMM-189 in the mouse model of mild traumatic brain injury. Herein, we report the further characterization of SMM-189 as a potent and selective CB2 inverse agonist, which acts as a noncompetitive inhibitor of CP 55,940. The ability of SMM-189 to regulate microglial activation, in terms of chemokine expression and cell morphology, has been determined. Finally, we have determined that SMM-189 possesses acceptable biopharmaceutical properties indicating that the triaryl class of CB2 inverse agonists are viable compounds for continued preclinical development for the treatment of neurodegenerative disorders and traumatic brain injury.

  1. Simultaneous Activation of Induced Heterodimerization between CXCR4 Chemokine Receptor and Cannabinoid Receptor 2 (CB2) Reveals a Mechanism for Regulation of Tumor Progression.

    Science.gov (United States)

    Coke, Christopher J; Scarlett, Kisha A; Chetram, Mahandranauth A; Jones, Kia J; Sandifer, Brittney J; Davis, Ahriea S; Marcus, Adam I; Hinton, Cimona V

    2016-05-06

    The G-protein-coupled chemokine receptor CXCR4 generates signals that lead to cell migration, cell proliferation, and other survival mechanisms that result in the metastatic spread of primary tumor cells to distal organs. Numerous studies have demonstrated that CXCR4 can form homodimers or can heterodimerize with other G-protein-coupled receptors to form receptor complexes that can amplify or decrease the signaling capacity of each individual receptor. Using biophysical and biochemical approaches, we found that CXCR4 can form an induced heterodimer with cannabinoid receptor 2 (CB2) in human breast and prostate cancer cells. Simultaneous, agonist-dependent activation of CXCR4 and CB2 resulted in reduced CXCR4-mediated expression of phosphorylated ERK1/2 and ultimately reduced cancer cell functions such as calcium mobilization and cellular chemotaxis. Given that treatment with cannabinoids has been shown to reduce invasiveness of cancer cells as well as CXCR4-mediated migration of immune cells, it is plausible that CXCR4 signaling can be silenced through a physical heterodimeric association with CB2, thereby inhibiting subsequent functions of CXCR4. Taken together, the data illustrate a mechanism by which the cannabinoid system can negatively modulate CXCR4 receptor function and perhaps tumor progression. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.

  2. Simultaneous Activation of Induced Heterodimerization between CXCR4 Chemokine Receptor and Cannabinoid Receptor 2 (CB2) Reveals a Mechanism for Regulation of Tumor Progression*

    Science.gov (United States)

    Coke, Christopher J.; Scarlett, Kisha A.; Chetram, Mahandranauth A.; Jones, Kia J.; Sandifer, Brittney J.; Davis, Ahriea S.; Marcus, Adam I.

    2016-01-01

    The G-protein-coupled chemokine receptor CXCR4 generates signals that lead to cell migration, cell proliferation, and other survival mechanisms that result in the metastatic spread of primary tumor cells to distal organs. Numerous studies have demonstrated that CXCR4 can form homodimers or can heterodimerize with other G-protein-coupled receptors to form receptor complexes that can amplify or decrease the signaling capacity of each individual receptor. Using biophysical and biochemical approaches, we found that CXCR4 can form an induced heterodimer with cannabinoid receptor 2 (CB2) in human breast and prostate cancer cells. Simultaneous, agonist-dependent activation of CXCR4 and CB2 resulted in reduced CXCR4-mediated expression of phosphorylated ERK1/2 and ultimately reduced cancer cell functions such as calcium mobilization and cellular chemotaxis. Given that treatment with cannabinoids has been shown to reduce invasiveness of cancer cells as well as CXCR4-mediated migration of immune cells, it is plausible that CXCR4 signaling can be silenced through a physical heterodimeric association with CB2, thereby inhibiting subsequent functions of CXCR4. Taken together, the data illustrate a mechanism by which the cannabinoid system can negatively modulate CXCR4 receptor function and perhaps tumor progression. PMID:26841863

  3. Cannabinoid CB1 receptor antagonist rimonabant disrupts nicotine reward-associated memory in rats.

    Science.gov (United States)

    Fang, Qin; Li, Fang-Qiong; Li, Yan-Qin; Xue, Yan-Xue; He, Ying-Ying; Liu, Jian-Feng; Lu, Lin; Wang, Ji-Shi

    2011-10-01

    Exposure to cues previously associated with drug intake leads to relapse by activating previously acquired memories. Based on previous findings, in which cannabinoid CB(1) receptors were found to be critically involved in specific aspects of learning and memory, we investigated the role of CB(1) receptors in nicotine reward memory using a rat conditioned place preference (CPP) model. In Experiment 1, rats were trained for CPP with alternating injections of nicotine (0.5mg/kg, s.c.) and saline to acquire the nicotine-conditioned memory. To examine the effects of rimonabant on the reconsolidation of nicotine reward memory, rats were administered rimonabant (0, 0.3, and 3.0mg/kg, i.p.) immediately after reexposure to the drug-paired context. In Experiment 2, rats were trained for CPP similarly to Experiment 1. To examine the effects of rimonabant on the reinstatement of nicotine reward memory, rimonabant (0, 0.3, and 3.0mg/kg, i.p.) was administered before the test of nicotine-induced CPP reinstatement. In Experiment 3, to evaluate whether rimonabant itself produces a reward memory, rats were trained for CPP with alternating injections of different doses of rimonabant (0, 0.3, and 3.0mg/kg) and saline. Rimonabant at a dose of 3.0mg/kg significantly disrupted the reconsolidation of nicotine memory and significantly blocked the reinstatement of nicotine-induced CPP. However, rimonabant itself did not produce CPP. These findings provide clear evidence that CB(1) receptors play a role in nicotine reward memory, suggesting that CB(1) receptor antagonists may be a potential target for managing nicotine addiction. Copyright © 2011 Elsevier Inc. All rights reserved.

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

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    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 controls [HC]). Untreated individuals with PTSD (N=25) with non-combat trauma histories, and TC (N=12) and HC (N=23) participated in a magnetic resonance (MR) imaging scan and a resting PET scan with the CB1 receptor antagonist radiotracer [11C]OMAR, which measures volume of distribution (VT) linearly related to CB1 receptor availability. Peripheral levels of anandamide, 2-arachidonoylglycerol (2-AG), oleoylethanolamide (OEA), palmitoylethanolamide (PEA), and cortisol were also assessed. In the PTSD group, relative to the HC and TC groups, we found elevated brain-wide [11C]OMAR VT values (F(2,53)=7.96, p=.001; 19.5% and 14.5% higher, respectively) which were most pronounced in women (F(1,53)=5.52, p=.023). Anandamide concentrations were reduced in the PTSD relative to the TC (53.1% lower) and HC (58.2% lower) groups. Cortisol levels were lower in the PTSD and TC groups relative to the HC group. Three biomarkers examined collectively—OMAR VT, anandamide, and cortisol—correctly classified nearly 85% of PTSD cases. These results suggest that abnormal CB1 receptor-mediated anandamide signaling is implicated in the etiology of PTSD, and provide a promising neurobiological model to develop novel, evidence-based pharmacotherapies for this disorder. PMID:23670490

  5. 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

  6. Cannabinoid 1 receptor knockout mice display cold allodynia, but enhanced recovery from spared-nerve injury-induced mechanical hypersensitivity.

    Science.gov (United States)

    Sideris, Alexandra; Piskoun, Boris; Russo, Lori; Norcini, Monica; Blanck, Thomas; Recio-Pinto, Esperanza

    2016-01-01

    The function of the Cannabinoid 1 receptor (CB1R) in the development of neuropathic pain is not clear. Mounting evidence suggest that CB1R expression and activation may contribute to pain. Cannabinoid 1 receptor knockout mice (CB1R-/-) generated on a C57Bl/6 background exhibit hypoalgesia in the hotplate assay and formalin test. These findings suggest that Cannabinoid 1 receptor expression mediates the responses to at least some types of painful stimuli. By using this mouse line, we sought to determine if the lack of Cannabinoid 1 receptor unveils a general hypoalgesic phenotype, including protection against the development of neuropathic pain. The acetone test was used to measure cold sensitivity, the electronic von Frey was used to measure mechanical thresholds before and after spared-nerve injury, and analysis of footprint patterns was conducted to determine if motor function is differentially affected after nerve-injury in mice with varying levels of Cannabinoid 1 receptor. At baseline, CB1R-/- mice were hypersensitive in the acetone test, and this phenotype was maintained after spared-nerve injury. Using calcium imaging of lumbar dorsal root ganglion (DRG) cultures, a higher percentage of neurons isolated from CB1R-/- mice were menthol sensitive relative to DRG isolated from wild-type (CB1R+/+) mice. Baseline mechanical thresholds did not differ among genotypes, and mechanical hypersensitivity developed similarly in the first two weeks following spared-nerve injury (SNI). At two weeks post-SNI, CB1R-/- mice recovered significantly from mechanical hypersensitivity, while the CB1R+/+ mice did not. Heterozygous knockouts (CB1R+/-) transiently developed cold allodynia only after injury, but recovered mechanical thresholds to a similar extent as the CB1R-/- mice. Sciatic functional indices, which reflect overall nerve health, and alternation coefficients, which indicate uniformity of strides, were not significantly different among genotypes. Cold allodynia and

  7. Immunohistochemical analysis of cannabinoid receptor 1 expression in steatotic rat livers.

    Science.gov (United States)

    Zduniak, Krzysztof; Ziółkowski, Piotr; Regnell, Pontus; Tollet-Egnell, Petra; Åkesson, Lina; Cooper, Martin E

    2016-04-01

    The primary aim of the present study was to determine the expression levels of cannabinoid receptor type 1 (CB1) in steatotic rat livers. The secondary aim was to clarify whether steatosis and inflammation are more marked in areas with increased CB1 overexpression. For ethical and economic reasons, the present study investigated tissue from archived liver blocks, which were obtained from 38 rats that had been euthanized during the course of previous research at the Karolinska Institute of the Karolinska University Hospital (Stockholm, Sweden) and Lund University (Malmö, Sweden). Liver tissue fixed in formalin and embedded in paraffin was used that had been sourced from 36 male Sprague Dawley rats (age, 7 weeks) and 2 rats (age, 180 days) lacking normal leptin receptors. The rat liver tissue was stained with antibodies against CB1 and counterstained with hematoxylin. The expression of CB1 and the number of cells overexpressing CB1 were determined. Steatosis was scored according to the Dixon scoring system. CB1 overexpression and steatosis were detected in hepatocytes from all 38 livers sampled. The expression of CB1 was more marked in hepatocytes localized next to portal triads. Near the central veins, the expression was significantly weaker. Steatosis was more marked in areas of increased CB1 overexpression. Lymphocyte infiltration was more commonly observed in areas of increased CB1 overexpression. Therefore, the present results indicate that CB1 receptors are overexpressed in areas with steatosis, and indicate that CB1 in hepatocytes contributes to the formation of steatosis in rats, even prior to its progression to steatohepatitis. These results are consistent with publications reporting that CB1 in hepatocytes increases lipogenesis and contributes to inflammation.

  8. The therapeutic potential of cannabis and cannabinoids.

    Science.gov (United States)

    Grotenhermen, Franjo; Müller-Vahl, Kirsten

    2012-07-01

    Cannabis-based medications have been a topic of intense study since the endogenous cannabinoid system was discovered two decades ago. In 2011, for the first time, a cannabis extract was approved for clinical use in Germany. Selective literature review. Cannabis-based medications exert their effects mainly through the activation of cannabinoid receptors (CB1 and CB2). More than 100 controlled clinical trials of cannabinoids or whole-plant preparations for various indications have been conducted since 1975. The findings of these trials have led to the approval of cannabis-based medicines (dronabinol, nabilone, and a cannabis extract [THC:CBD=1:1]) in several countries. In Germany, a cannabis extract was approved in 2011 for the treatment of moderate to severe refractory spasticity in multiple sclerosis. It is commonly used off label for the treatment of anorexia, nausea, and neuropathic pain. Patients can also apply for government permission to buy medicinal cannabis flowers for self-treatment under medical supervision. The most common side effects of cannabinoids are tiredness and dizziness (in more than 10% of patients), psychological effects, and dry mouth. Tolerance to these side effects nearly always develops within a short time. Withdrawal symptoms are hardly ever a problem in the therapeutic setting. There is now clear evidence that cannabinoids are useful for the treatment of various medical conditions.

  9. Cannabinoids and centrak neuropathic pain. A review (Cannabinoidi e dolore neuropatico centrale. Una rassegna

    Directory of Open Access Journals (Sweden)

    Francesco Crestani

    2014-03-01

    Full Text Available Only recently, the medical community highlighted the pharmacological scientific bases of the effects of Cannabis. The most important active principle, Delta-9-tetrahydrocannabinol was identified in the second half of the last century, and receptors were subsequently identified and endogenous ligands, called endocannabinoids, were characterized. The effectiveness of the cannabinoids in the treatment of nausea and vomit due to anti-neoplastic chemotherapy and in the wasting-syndrome during AIDS is recognized. Moreover, the cannabinoids have shown analgesic properties, particularly interesting with regard to the central neuropathic pain. This article will review the current knowledge and will give practical guidance on how to proceed in prescribing cannabinoids.

  10. Regulation of hippocampal cannabinoid CB1 receptor actions by adenosine A1 receptors and chronic caffeine administration: implications for the effects of Δ9-tetrahydrocannabinol on spatial memory.

    Science.gov (United States)

    Sousa, Vasco C; Assaife-Lopes, Natália; Ribeiro, Joaquim A; Pratt, Judith A; Brett, Ros R; Sebastião, Ana M

    2011-01-01

    The cannabinoid CB(1) receptor-mediated modulation of γ-aminobutyric acid (GABA) release from inhibitory interneurons is important for the integrity of hippocampal-dependent spatial memory. Although adenosine A(1) receptors have a central role in fine-tuning excitatory transmission in the hippocampus, A(1) receptors localized in GABAergic cells do not directly influence GABA release. CB(1) and A(1) receptors are the main targets for the effects of two of the most heavily consumed psychoactive substances worldwide: Δ(9)-tetrahydrocannabinol (THC, a CB(1) receptor agonist) and caffeine (an adenosine receptor antagonist). We first tested the hypothesis that an A(1)-CB(1) interaction influences GABA and glutamate release in the hippocampus. We found that A(1) receptor activation attenuated the CB(1)-mediated inhibition of GABA and glutamate release and this interaction was manifested at the level of G-protein activation. Using in vivo and in vitro approaches, we then investigated the functional implications of the adenosine-cannabinoid interplay that may arise following chronic caffeine consumption. Chronic administration of caffeine in mice (intraperitoneally, 3 mg/kg/day, for 15 days, >12 h before trials) led to an A(1)-mediated enhancement of the CB(1)-dependent acute disruptive effects of THC on a short-term spatial memory task, despite inducing a reduction in cortical and hippocampal CB(1) receptor number and an attenuation of CB(1) coupling with G protein. A(1) receptor levels were increased following chronic caffeine administration. This study shows that A(1) receptors exert a negative modulatory effect on CB(1)-mediated inhibition of GABA and glutamate release, and provides the first evidence of chronic caffeine-induced alterations on the cannabinoid system in the cortex and hippocampus, with functional implications in spatial memory.

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

    International Nuclear Information System (INIS)

    Yan Zhencheng; Liu Daoyan; Zhang Lili; Shen Chenyi; Ma Qunli; Cao Tingbing; Wang Lijuan; Nie Hai; Zidek, Walter; Tepel, Martin; Zhu Zhiming

    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-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

  12. Effects of cannabinoid CB₁ receptor antagonist rimonabant on acquisition and reinstatement of psychostimulant reward memory in mice.

    Science.gov (United States)

    Yu, Lu-Lu; Zhou, Shuang-Jiang; Wang, Xue-Yi; Liu, Jian-Feng; Xue, Yan-Xue; Jiang, Wengao; Lu, Lin

    2011-02-02

    Drug addiction processes are considered to be mainly controlled by the mesocorticolimbic dopamine system. Cannabinoids, a class of psychoactive drugs of abuse, elicit their rewarding and pharmacological effects through the endocannabinoid system. Previous research has indicated that dopaminergic neurons in the mesocorticolimbic system are also under the control of the endocannabinoid system. Recently, evidence has suggested that the endocannabinoid system may also participate in the modulation of the common reward system. The present study examined whether rimonabant, a cannabinoid CB₁ receptor antagonist, disrupts the acquisition and reinstatement of psychostimulant reward memory measured by conditioned place preference (CPP). Mice were trained to acquire methamphetamine or cocaine-induced CPP. A priming injection of methamphetamine (0.5 mg/kg, i.p.) or cocaine (5 mg/kg, i.p.) was respectively given to reinstate methamphetamine or cocaine-induced CPP after extinction. Vehicle or rimonabant (1 or 3 mg/kg, i.p.) was administered at different time-points: 30 min before each CPP training session (acquisition) or 30 min before the priming injection (reinstatement). Rimonabant at doses of 1 and 3 mg/kg significantly inhibited the acquisition of methamphetamine- and cocaine-induced CPP. At the high dose (3 mg/kg), rimonabant disrupted the reinstatement of extinguished methamphetamine- or cocaine-induced CPP. These findings indicate that cannabinoid CB₁ receptors play a major role in psychostimulant reward memory, and rimonabant may be a potential pharmacotherapy for psychostimulant addiction. Copyright © 2010. Published by Elsevier B.V.

  13. Effects on food intake and blood lipids of cannabinoid receptor 1 antagonist treatment in lean rats.

    Science.gov (United States)

    Bennetzen, Marianne F; Nielsen, Maria P; Richelsen, Bjørn; Pedersen, Steen B

    2008-11-01

    Endocannabinoids act through the cannabinoid receptor 1 (CB1) and has both orexigenic and peripheral metabolic effects. It is not yet fully understood whether all the beneficial effects on the metabolic profile by CB1 antagonism are induced by the weight loss or also by direct peripheral effects. The present study was intended to further elucidate this question and to investigate whether tolerance development to the hypophagic effect could be attenuated by cyclic treatment. We performed an intervention study in 40 lean rats over 4 weeks. The rats were divided in four groups: a control group, two groups treated with the CB1 antagonist Rimonabant either continuously or cyclically, and one group pair fed with the continuous Rimonabant group to obtain the same body weight. During the first 6 days, food intake was less in the continuous Rimonabant group compared to the control group (P acids (nonesterified fatty acid, NEFA) were significantly reduced in both treated groups compared to the untreated groups, and levels of triglycerides showed the same tendency. Cyclic treatment with Rimonabant is able to inhibit tolerance development on food intake, which resulted in reduction in body weight. Rimonabant treatment is associated with reduced serum levels of glycerol, NEFA, and triglyceride which seem independent of body weight changes.

  14. 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. Copyright © 2015 Elsevier Inc. All rights reserved.

  15. R+-methanandamide inhibits tracheal response to endogenously released acetylcholine via capsazepine-sensitive receptors.

    Science.gov (United States)

    Nieri, Paola; Martinotti, Enrica; Testai, Lara; Adinolfi, Barbara; Calderone, Vincenzo; Breschi, Maria Cristina

    2003-01-10

    The effects of cannabinoid drugs on the cholinergic response evoked by electrical field stimulation (0.2 ms pulse width, 20 V amplitude, 10 Hz, 7.5 s train duration) in guinea-pig tracheal preparations were investigated. The stable analogue of the endocannabinoid anandamide, R(+)-methanandamide (10(-7)-10(-4) M), produced a dose-dependent inhibition (up to 27+/-5% of control) of electrical field stimulation-mediated atropine-sensitive response. This effect was not blocked by the selective cannabinoid CB(1) receptor antagonist N-(piperidin-1-yl)-5-(4-chlorophenyl)-1-(2,4-dichlorophenyl)-4-methyl-1H-pyrazole-3 carboxamide hydrochloride (SR 141716A; 10(-6) M), and was not reproduced with the cannabinoid CB(1)/CB(2) receptor agonist R(+)-[2,3-dihydro-5-methyl-[(morpholinyl)methyl]pyrrolo [1,2,3-de]-1,4-benzoxazin-6-yl]-(1-naphthalenyl)methanone mesylate) (WIN 55,212-2; 10(-8)-10(-5) M) or the cannabinoid CB(2) receptor selective agonist 1-propyl-2-methyl-3-(1-naphthoyl)indole (JWH-015; 10(-8)-10(-5) M); it was, on the contrary, antagonized by the vanilloid antagonist 2-[2-(4-chlorophenyl)ethyl-amino-thiocarbonyl]-7,8-dihydroxy-2,3,4,5-tetrahydro-1H-2 benzazepine (capsazepine; 10(-6) M). At the postjunctional level, neither R(+)-methanandamide nor WIN 55,212-2 nor JWH-015 did affect tracheal contractions induced by exogenous acetylcholine (10(-6) M). An inhibitory vanilloid receptor-mediated effect on the cholinergic response evoked by electrical stimulation was confirmed with the vanilloid agonist capsaicin, at doses (3-6 x 10(-8) M) which poorly influenced the basal smooth muscle tone of trachea. In conclusion, our data indicate that in guinea-pig trachea (a) neither CB(1) nor CB(2) cannabinoid receptor-mediated modulation of acetylcholine release occurs; (b) vanilloid VR1-like receptors appear involved in R(+)-methanandamide inhibitory activity on the cholinergic response to electrical field stimulation.

  16. Plant cannabinoids: a neglected pharmacological treasure trove.

    Science.gov (United States)

    Mechoulam, Raphael

    2005-12-01

    Most of the cannabinoids in Cannabis sativa L. have not been fully evaluated for their pharmacological activity. A publication in this issue presents evidence that a plant cannabinoid, Delta(9)-tetrahydrocannabivarin is a potent antagonist of anandamide, a major endogenous cannabinoid. It seems possible that many of the non-psychoactive constituents of this plant will be of biological interest.

  17. The peripheral cannabinoid receptor Cb2, frequently expressed on AML blasts, either induces a neutrophilic differentiation block or confers abnormal migration properties in a ligand-dependent manner

    NARCIS (Netherlands)

    M. Alberich-Jorda (Meritxell); N. Rayman (Nazik); M. Tas (Marjolein); S.E. Verbakel (Sandra); N. Battista (Natalia); K. van Lom (Kirsten); B. Löwenberg (Bob); M. Maccarrone (Mauro); H.R. Delwel (Ruud)

    2004-01-01

    textabstractCb2, the gene encoding the peripheral cannabinoid receptor, is located in a common virus integration site and is overex-pressed in retrovirally induced murine myeloid leukemias. Here we show that this G protein-coupled receptor (GPCR) is also aberrantly expressed in a

  18. Consequences of Adolescent Exposure to the Cannabinoid Receptor Agonist WIN55,212-2 on Working Memory in Female Rats

    Directory of Open Access Journals (Sweden)

    Erin K. Kirschmann

    2017-07-01

    Full Text Available Marijuana is a prevalent illicit substance used by adolescents, and several studies have indicated that adolescent use can lead to long-term cognitive deficits including problems with attention and memory. However, preclinical animal studies that observe cognitive deficits after cannabinoid exposure during adolescence utilize experimenter administration of doses of cannabinoids that may exceed what an organism would choose to take, suggesting that contingency and dose are critical factors that need to be addressed in translational models of consequences of cannabinoid exposure. Indeed, we recently developed an adolescent cannabinoid self-administration paradigm in male rats, and found that prior adolescent self-administration of the cannabinoid receptor agonist WIN55,212-2 (WIN resulted in improved working memory performance in adulthood. In addition, the doses self-administered were not as high as those that are found to produce memory deficits. However, given known sex differences in both drug self-administration and learning and memory processes, it is possible that cannabinoid self-administration could have different cognitive consequences in females. Therefore, we aimed to explore the effects of self-administered vs. experimenter-administered WIN in adolescent female rats on adult cognitive function. Female rats were trained to self-administer WIN daily throughout adolescence (postnatal day 34–59. A control group self-administered vehicle solution. The acute effects of adolescent WIN self-administration on memory were determined using a short-term spatial memory test 24 h after final SA session; and the long-term effects on cognitive performance were assessed during protracted abstinence in adulthood using a delayed-match-to-sample working memory task. In a separate experiment, females were given daily intraperitoneal (IP injections of a low or high dose of WIN, corresponding to self-administered and typical experimenter

  19. Consequences of Adolescent Exposure to the Cannabinoid Receptor Agonist WIN55,212-2 on Working Memory in Female Rats.

    Science.gov (United States)

    Kirschmann, Erin K; McCalley, Daniel M; Edwards, Caitlyn M; Torregrossa, Mary M

    2017-01-01

    Marijuana is a prevalent illicit substance used by adolescents, and several studies have indicated that adolescent use can lead to long-term cognitive deficits including problems with attention and memory. However, preclinical animal studies that observe cognitive deficits after cannabinoid exposure during adolescence utilize experimenter administration of doses of cannabinoids that may exceed what an organism would choose to take, suggesting that contingency and dose are critical factors that need to be addressed in translational models of consequences of cannabinoid exposure. Indeed, we recently developed an adolescent cannabinoid self-administration paradigm in male rats, and found that prior adolescent self-administration of the cannabinoid receptor agonist WIN55,212-2 (WIN) resulted in improved working memory performance in adulthood. In addition, the doses self-administered were not as high as those that are found to produce memory deficits. However, given known sex differences in both drug self-administration and learning and memory processes, it is possible that cannabinoid self-administration could have different cognitive consequences in females. Therefore, we aimed to explore the effects of self-administered vs. experimenter-administered WIN in adolescent female rats on adult cognitive function. Female rats were trained to self-administer WIN daily throughout adolescence (postnatal day 34-59). A control group self-administered vehicle solution. The acute effects of adolescent WIN self-administration on memory were determined using a short-term spatial memory test 24 h after final SA session; and the long-term effects on cognitive performance were assessed during protracted abstinence in adulthood using a delayed-match-to-sample working memory task. In a separate experiment, females were given daily intraperitoneal (IP) injections of a low or high dose of WIN, corresponding to self-administered and typical experimenter-administered doses, respectively, or

  20. Endogenous hallucinogens as ligands of the trace amine receptors: a possible role in sensory perception.

    Science.gov (United States)

    Wallach, J V

    2009-01-01

    While the endogenous hallucinogens, N,N-dimethyltryptamine, 5-hydroxy-N,N-dimethyl-tryptamine and 5-methoxy-N,N-dimethyltryptamine, have been acknowledged as naturally occurring components of the mammalian body for decades, their biological function remains as elusive now as it was at the time of their discovery. The recent discovery of the trace amine associated receptors and the activity of DMT and other hallucinogenic compounds at these receptor sites leads to the hypothesis that the endogenous hallucinogens act as neurotransmitters of a subclass of these trace amine receptors. Additionally, while activity at the serotonin 5-HT2A receptor has been proposed as being responsible for the hallucinogenic affects of administered hallucinogens, in their natural setting the 5-HT2A receptor may not interact with the endogenous hallucinogens at all. Additionally 5-HT2A agonist activity is unable to account for the visual altering effects of many of the administered hallucinogens; these effects may be mediated by one of the endogenous hallucinogen trace amine receptors rather than the serotonin 5-HT2A receptor. Therefore, activity at the trace amine receptors, in addition to serotonin receptors, may play a large role in the sensory altering effects of administered hallucinogens and the trace amine receptors along with their endogenous hallucinogen ligands may serve an endogenous role in mediating sensory perception in the mammalian central nervous system. Thus the theory proposed states that these compounds act as true endogenous hallucinogenic transmitters acting in regions of the central nervous system involved in sensory perception.

  1. Cannabinoid CB1 Receptors Are Localized in Striated Muscle Mitochondria and Regulate Mitochondrial Respiration

    Directory of Open Access Journals (Sweden)

    Juan Mendizabal-Zubiaga

    2016-10-01

    Full Text Available The cannabinoid type 1 (CB1 receptor is widely distributed in the brain and peripheral organs where it regulates cellular functions and metabolism. In the brain, CB1 is mainly localized on presynaptic axon terminals but is also found on mitochondria (mtCB1, where it regulates cellular respiration and energy production. Likewise, CB1 is localized on muscle mitochondria, but very little is known about it. The aim of this study was to further investigate in detail the distribution and functional role of mtCB1 in three different striated muscles. Immunoelectron microscopy for CB1 was used in skeletal muscles (gastrocnemius and rectus abdominis and myocardium from wild-type and CB1-KO mice. Functional assessments were performed in mitochondria purified from the heart of the mice and the mitochondrial oxygen consumption upon application of different acute delta-9-tetrahidrocannabinol (Δ9-THC concentrations (100 nM or 200 nM was monitored. About 26% of the mitochondrial profiles in gastrocnemius, 22% in the rectus abdominis and 17% in the myocardium expressed CB1. Furthermore, the proportion of mtCB1 versus total CB1 immunoparticles was about 60% in the gastrocnemius, 55% in the rectus abdominis and 78% in the myocardium. Importantly, the CB1 immunolabeling pattern disappeared in muscles of CB1-KO mice. Functionally, acute 100 nM or 200 nM THC treatment specifically decreased mitochondria coupled respiration between 12% and 15% in wild-type isolated mitochondria of myocardial muscles but no significant difference was noticed between THC treated and vehicle in mitochondria isolated from CB1-KO heart. Furthermore, gene expression of key enzymes involved in pyruvate synthesis, tricarboxylic acid (TCA cycle and mitochondrial respiratory chain was evaluated in the striated muscle of CB1-WT and CB1-KO. CB1-KO showed an increase in the gene expression of Eno3, Pkm2, and Pdha1, suggesting an increased production of pyruvate. In contrast, no significant

  2. 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

    Science.gov (United States)

    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 alterations in cell proliferation. To this end, we examined whether pharmacological blockade of either CB1 (Rimonabant, 3 mg/kg) or CB2 receptors (AM630, 3 mg/kg) would affect cell proliferation [the cells were labeled with 5-bromo-2′-deoxyuridine (BrdU)] in the subventricular zone (SVZ) of the lateral ventricle and the dentate subgranular zone (SGZ). Additionally, we measured cell apoptosis (as monitored by the expression of cleaved caspase-3) and glial activation [by analyzing the expression of glial fibrillary acidic protein (GFAP) and Iba-1] in the striatum and hippocampus during acute and repeated (4 days) cocaine administration (20 mg/kg). The results showed that acute cocaine exposure decreased the number of BrdU-immunoreactive (ir) cells in the SVZ and SGZ. In contrast, repeated cocaine exposure reduced the number of BrdU-ir cells only in the SVZ. Both acute and repeated cocaine exposure increased the number of cleaved caspase-3-, GFAP- and Iba1-ir cells in the hippocampus, and this effect was counteracted by AM630 or Rimonabant, which increased the number of BrdU-, GFAP-, and Iba1-ir cells in the hippocampus. These results indicate that the changes in neurogenic, apoptotic and gliotic processes that were produced by repeated cocaine administration were normalized by pharmacological blockade of CB1 and CB2. The restorative effects of cannabinoid receptor blockade on hippocampal cell proliferation were associated with the prevention of the induction of conditioned

  3. 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.

  4. The role of the cannabinoid receptor in adolescents' processing of facial expressions.

    Science.gov (United States)

    Ewald, Anais; Becker, Susanne; Heinrich, Angela; Banaschewski, Tobias; Poustka, Luise; Bokde, Arun; Büchel, Christian; Bromberg, Uli; Cattrell, Anna; Conrod, Patricia; Desrivières, Sylvane; Frouin, Vincent; Papadopoulos-Orfanos, Dimitri; Gallinat, Jürgen; Garavan, Hugh; Heinz, Andreas; Walter, Henrik; Ittermann, Bernd; Gowland, Penny; Paus, Tomáš; Martinot, Jean-Luc; Paillère Martinot, Marie-Laure; Smolka, Michael N; Vetter, Nora; Whelan, Rob; Schumann, Gunter; Flor, Herta; Nees, Frauke

    2016-01-01

    The processing of emotional faces is an important prerequisite for adequate social interactions in daily life, and might thus specifically be altered in adolescence, a period marked by significant changes in social emotional processing. Previous research has shown that the cannabinoid receptor CB1R is associated with longer gaze duration and increased brain responses in the striatum to happy faces in adults, yet, for adolescents, it is not clear whether an association between CBR1 and face processing exists. In the present study we investigated genetic effects of the two CB1R polymorphisms, rs1049353 and rs806377, on the processing of emotional faces in healthy adolescents. They participated in functional magnetic resonance imaging during a Faces Task, watching blocks of video clips with angry and neutral facial expressions, and completed a Morphed Faces Task in the laboratory where they looked at different facial expressions that switched from anger to fear or sadness or from happiness to fear or sadness, and labelled them according to these four emotional expressions. A-allele versus GG-carriers in rs1049353 displayed earlier recognition of facial expressions changing from anger to sadness or fear, but not for expressions changing from happiness to sadness or fear, and higher brain responses to angry, but not neutral, faces in the amygdala and insula. For rs806377 no significant effects emerged. This suggests that rs1049353 is involved in the processing of negative facial expressions with relation to anger in adolescence. These findings add to our understanding of social emotion-related mechanisms in this life period. © 2015 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.

  5. [Expression of cannabinoid receptor I during mice skin incised wound healing course].

    Science.gov (United States)

    Zhao, Zhen-bin; Guan, Da-wei; Liu, Wei-wei; Wang, Tao; Fan, Yan-yan; Cheng, Zi-hui; Zheng, Ji-long; Hu, Geng-yi

    2010-08-01

    To investigate the expression of cannabinoid receptor I (CB1R) during mice skin incised wound healing course and time-dependent changes of CB1R in wound age determination. The changes of CBIR expression in skin incised wound were detected by immunohistochemistry and Western blotting. The control group showed a low expression of CB1R detected mainly in epidermis, hair follicles, sebaceous gland and dermomuscular layer. CB1R expression was undetectable in neutrophils in the wound specimens from 6h to 12h post-injury. CB1R positive cells were mostly mononuclear cells (MNCs) and fibroblastic cells (FBCs) from 1 d to 5 d post-injury. CB1R positive cells were mostly FBCs from 7 d to 14d post-injury. The ratio of the CB1R positive cells increased gradually in the wound specimens from 6 h to 3 d post-injury, reached peak level at 5 d, and then decreased gradually from 7d to 14 d post-injury. The positive bands of CB1R were observed in all time points of the wound healing course by Western blotting. The expression peak showed at 5 d post-injury. CB1R is activated during the wound healing course. The expression of CB1R is found in mononuclear cells, which could be involved in inflammation reaction. CBIR is observed in fibroblastic cells, which could participate in the wound healing. CB1R may be a potentially useful marker for determination of wound healing age.

  6. Preparation of iodine-123 labeled AM251: a potential SPECT radioligand for the brain cannabinoid CB1 receptor

    International Nuclear Information System (INIS)

    Lan, Ruoxi; Makriyannis, Alexandros; Gatley, S.J.

    1996-01-01

    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)

  7. Cannabinoid Type 1 Receptor (CB1) Ligands with Therapeutic Potential for Withdrawal Syndrome in Chemical Dependents of Cannabis sativa.

    Science.gov (United States)

    Ferreira, Jaderson V; Chaves, Gisele A; Marino, Bianca L B; Sousa, Kessia P A; Souza, Lucilene R; Brito, Maiara F B; Teixeira, Hueldem R C; da Silva, Carlos H T P; Santos, Cleydson B R; Hage-Melim, Lorane I S

    2017-08-22

    Cannabis sativa withdrawal syndrome is characterized mainly by psychological symptoms. By using computational tools, the aim of this study was to propose drug candidates for treating withdrawal syndrome based on the natural ligands of the cannabinoid type 1 receptor (CB1). One compound in particular, 2-n-butyl-5-n-pentylbenzene-1,3-diol (ZINC1730183, also known as stemphol), showed positive predictions as a human CB1 ligand and for facile synthetic accessibility. Therefore, ZINC1730183 is a favorable candidate scaffold for further research into pharmacotherapeutic alternatives to treat C. sativa withdrawal syndrome. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  8. 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).

  9. Candidate PET radioligands for cannabinoid CB{sub 1} receptors: [{sup 18}F]AM5144 and related pyrazole compounds

    Energy Technology Data Exchange (ETDEWEB)

    Zizhong, Li [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); Qian, Liu [Center for Drug Discovery, Northeastern University, Boston, MA 02115 (United States); Thotapally, Rajesh [Center for Drug Discovery, Northeastern University, Boston, MA 02115 (United States); Yushin, Ding [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)

    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.

  10. 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.

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

    International Nuclear Information System (INIS)

    Li Zizhong; Gifford, Andrew; Liu Qian; Thotapally, Rajesh; Ding Yushin; Makriyannis, Alexandros; Gatley, S. John

    2005-01-01

    Introduction: The mammalian brain contains abundant G protein-coupled cannabinoid CB 1 receptors that respond to Δ 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 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-[ 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-[ 18 F]fluoroaniline. The labeled precursor was synthesized from 1-[ 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/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 CB 1 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 CB 1 receptor that may require very lipophilic ligands

  12. Cannabinoid Receptor Type 1 Expression in the Developing Avian Retina: Morphological and Functional Correlation With the Dopaminergic System

    Directory of Open Access Journals (Sweden)

    Luzia da Silva Sampaio

    2018-03-01

    Full Text Available The avian retina has been used as a model to study signaling by different neuro- and gliotransmitters. It is unclear how dopaminergic and cannabinoid systems are related in the retina. Here we studied the expression of type 1 and 2 cannabinoid receptors (CB1 and CB2, as well as monoacylglycerol lipase (MAGL, the enzyme that degrades 2-arachidonoylglycerol (2-AG, during retina development. Our data show that CB1 receptor is highly expressed from embryonic day 5 (E5 until post hatched day 7 (PE7, decreasing its levels throughout development. CB1 is densely found in the ganglion cell layer (GCL and inner plexiform layer (IPL. CB2 receptor was also found from E5 until PE7 with a decrease in its contents from E9 afterwards. CB2 was mainly present in the lamination of the IPL at PE7. MAGL is expressed in all retinal layers, mainly in the IPL and OPL from E9 to PE7 retina. CB1 and CB2 were found both in neurons and glia cells, but MAGL was only expressed in Müller glia. Older retinas (PE7 show CB1 positive cells mainly in the INL and co-expression of CB1 and tyrosine hydroxylase (TH are shown in a few cells when both systems are mature. CB1 co-localized with TH and was heavily associated to D1 receptor labeling in primary cell cultures. Finally, cyclic AMP (cAMP was activated by the selective D1 agonist SKF38393, and inhibited when cultures were treated with WIN55, 212–2 (WIN in a CB1 dependent manner. The results suggest a correlation between the endocannabinoid and dopaminergic systems (DSs during the avian retina development. Activation of CB1 limits cAMP accumulation via D1 receptor activation and may influence embryological parameters during avian retina differentiation.

  13. Decreased in vivo availability of the cannabinoid type 2 receptor in Alzheimer's disease

    Energy Technology Data Exchange (ETDEWEB)

    Ahmad, Rawaha; Laere, Koen van [KU Leuven and University Hospitals Leuven, Department of Imaging and Pathology, Nuclear Medicine and Molecular Imaging, Leuven (Belgium); University Hospital Leuven, Division of Nuclear Medicine, Leuven (Belgium); Postnov, Andrey [KU Leuven and University Hospitals Leuven, Department of Imaging and Pathology, Nuclear Medicine and Molecular Imaging, Leuven (Belgium); National Research Nuclear University MEPhI, Moscow (Russian Federation); Bormans, Guy [KU Leuven, Laboratory for Radiopharmacy, Leuven (Belgium); Versijpt, Jan [University Hospital Brussels, Department of Neurology, Brussels (Belgium); Vandenbulcke, Mathieu [KU Leuven and University Hospitals Leuven, Old Age Psychiatry, Department of Psychiatry, Leuven (Belgium)

    2016-11-15

    The cannabinoid type 2 receptor (CB{sub 2}R) is expressed by immune cells such as monocytes and macrophages. In the brain, CB{sub 2}R is primarily found on microglia. CB{sub 2}R upregulation has been reported in animal models of Alzheimer's disease, with a preferential localization near amyloid beta (Aβ) plaques, and in patients post mortem. We performed in vivo brain imaging and kinetic modelling of the CB{sub 2}R tracer [{sup 11}C]NE40 in healthy controls (HC) and in patients with Alzheimer's disease (AD) to investigate whether higher CB{sub 2}R availability regionally colocalized to Aβ deposits is present in vivo. Dynamic 90-min [{sup 11}C]NE40 PET scans were performed in eight HC and nine AD patients with full kinetic modelling using arterial sampling and metabolite correction and partial volume correction. All AD patients received a static [{sup 11}C]PIB scan 40 min after injection. In four HC, a retest scan with [{sup 11}C]NE40 PET was performed within 9 weeks to investigate test-retest characteristics. [{sup 11}C]NE40 was metabolized quickly leading to 50 % of intact tracer 20 min after injection and 20 % at 90 min. A two-tissue kinetic model fitted most of the time-activity curves best; both binding potential (BP{sub ND}) and distribution volume (V{sub T}) parameters could be used. Brain uptake was generally low with an average K{sub 1} value of 0.07 ml/min/ml tissue. V{sub T} and BP{sub ND} were in the range of 0.7 - 1.8 and 0.6 - 1.6, respectively. Test values in HC were about 30 % for V{sub T} and BP{sub ND}. AD patients showed overall significantly lower CB{sub 2}R binding. No relationship was found between regional or global amyloid load and CB{sub 2}R availability. Kinetic modelling of [{sup 11}C]NE40 is possible with a two-tissue reversible model. In contrast to preclinical and post-mortem data, [{sup 11}C]NE40 PET shows lower CB{sub 2}R availability in vivo in AD patients, with no relationship to Aβ plaques. A possible explanation for

  14. Cannabinoid CB2 receptor agonists protect the striatum against malonate toxicity: relevance for Huntington’s disease

    Science.gov (United States)

    Sagredo, Onintza; González, Sara; Aroyo, Ilia; Pazos, María Ruth; Benito, Cristina; Lastres-Becker, Isabel; Romero, Juan P.; Tolón, Rosa M.; Mechoulam, Raphael; Brouillet, Emmanuel; Romero, Julián; Fernández-Ruiz, Javier

    2009-01-01

    Cannabinoid agonists might serve as neuroprotective agents in neurodegenerative disorders. Here, we examined this hypothesis in a rat model of Huntington’s disease (HD) generated by intrastriatal injection of the mitochondrial complex II inhibitor malonate. Our results showed that only compounds able to activate CB2 receptors were capable of protecting striatal projection neurons from malonate-induced death. That CB2 receptor agonists are neuroprotective was confirmed by using the selective CB2 receptor antagonist, SR144528, and by the observation that mice deficient in CB2 receptor were more sensitive to malonate than wild-type animals. CB2 receptors are scarce in the striatum in healthy conditions but they are markedly up-regulated after the lesion with malonate. Studies of double immunostaining revealed a significant presence of CB2 receptors in cells labelled with the marker of reactive microglia OX-42, and also in cells labelled with GFAP (a marker of astrocytes). We further showed that the activation of CB2 receptors significantly reduced the levels of tumor necrosis factor-α (TNF-α) that had been increased by the lesion with malonate. In summary, our results demonstrate that stimulation of CB2 receptors protect the striatum against malonate toxicity, likely through a mechanism involving glial cells, in particular reactive microglial cells in which CB2 receptors would be up-regulated in response to the lesion. Activation of these receptors would reduce the generation of proinflammatory molecules like TNF-α. Altogether our results support the hypothesis that CB2 receptors could constitute a therapeutic target to slowdown neurodegeneration in HD. PMID:19115380

  15. 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.

  16. Exogenous or endogenous Toll-like receptor ligands: which is the MVP in tumorigenesis?

    Science.gov (United States)

    Yu, Li; Wang, Liantang; Chen, Shangwu

    2012-03-01

    Toll-like receptors (TLRs) are a class of pattern recognition receptors sensing microbial components and triggering an immune response against pathogens. In addition to their role in anti-infection immunity, increasing evidence indicates that engagement of TLRs can promote cancer cell survival and proliferation, induce tumor immune evasion, and enhance tumor metastasis and chemoresistance. Recent studies have demonstrated that endogenous molecules or damage-associated molecular patterns released from damaged/necrotic tissues are capable of activating TLRs and that the endogenous ligands-mediated TLR signaling is implicated in the tumor development and affects the therapeutic efficacy of tumors. Since both exogenous and endogenous TLR ligands can initiate TLR signaling, which is the most valuable player in tumor development becomes an interesting question. Here, we summarize the effect of TLR signaling on the development and progression of tumors, and discuss the role of exogenous and endogenous TLR ligands in the tumorigenesis.

  17. Pharmacokinetic/pharmaco-dynamic modelling and simulation of the effects of different cannabinoid receptor type 1 antagonists on (9)-tetrahydrocannabinol challenge tests

    NARCIS (Netherlands)

    Guan, Zheng; Klumpers, Linda E.; Oyetayo, Olubukayo-Opeyemi; Heuberger, Jules; van Gerven, Joop M. A.; Stevens, Jasper

    Aim: The severe psychiatric side effects of cannabinoid receptor type 1 (CB1) antagonists hampered their wide development but this might be overcome by careful management of drug development with pharmacokinetic/pharmacodynamic (PK/PD) analyses. PK/PD models suitable for direct comparison of

  18. Interactions of the opioid and cannabinoid systems in reward: Insights from knockout studies

    Directory of Open Access Journals (Sweden)

    Katia eBefort

    2015-02-01

    Full Text Available The opioid system consists of three receptors, mu, delta, and kappa, which are activated by endogenous opioid peptides (enkephalins, endorphins and dynorphins. The endogenous cannabinoid system comprises lipid neuromodulators (endocannabinoids, enzymes for their synthesis and their degradation and two well-characterized receptors, cannabinoid receptors CB1 and CB2. These systems play a major role in the control of pain as well as in mood regulation, reward processing and the development of addiction. Both opioid and cannabinoid receptors are coupled to G proteins and are expressed throughout the brain reinforcement circuitry. Extending classical pharmacology, research using genetically modified mice has provided important progress in the identification of the specific contribution of each component of these endogenous systems in vivo on reward process. This review will summarize available genetic tools and our present knowledge on the consequences of gene knockout on reinforced behaviors in both systems, with a focus on their potential interactions. A better understanding of opioid-cannabinoid interactions may provide novel strategies for therapies in addicted individuals.

  19. Cannabinoid receptors activation and glucocorticoid receptors deactivation in the amygdala prevent the stress-induced enhancement of a negative learning experience.

    Science.gov (United States)

    Ramot, Assaf; Akirav, Irit

    2012-05-01

    The enhancement of emotional memory is clearly important as emotional stimuli are generally more significant than neutral stimuli for surviving and reproduction purposes. Yet, the enhancement of a negative emotional memory following exposure to stress may result in dysfunctional or intrusive memory that underlies several psychiatric disorders. Here we examined the effects of stress exposure on a negative emotional learning experience as measured by a decrease in the magnitude of the expected quantity of reinforcements in an alley maze. In contrast to other fear-related negative experiences, reward reduction is more associated with frustration and is assessed by measuring the latency to run the length of the alley to consume the reduced quantity of reward. We also examined whether the cannabinoid receptors agonist WIN55,212-2 (5 μg/side) and the glucocorticoid receptors (GRs) antagonist RU-486 (10 ng/side) administered into the rat basolateral amygdala (BLA) could prevent the stress-induced enhancement. We found that intra-BLA RU-486 or WIN55,212 before stress exposure prevented the stress-induced enhancement of memory consolidation for reduction in reward magnitude. These findings suggest that cannabinoid receptors and GRs in the BLA are important modulators of stress-induced enhancement of emotional memory. Copyright © 2012 Elsevier Inc. All rights reserved.

  20. Polymorphisms of the dopamine D4 receptor gene (DRD4 VNTR) and cannabinoid CB1 receptor gene (CNR1) are not strongly related to cue-reactivity after alcohol exposure

    NARCIS (Netherlands)

    Wildenberg, E. van den; Janssen, R.G.J.H.; Hutchison, K.E.; Breukelen, G.J.P. van; Wiers, R.W.H.J.

    2007-01-01

    Polymorphisms in the D4 dopamine receptor gene (DRD4) and the CB1 cannabinoid receptor gene (CNR1) have been associated with a differential response to alcohol after consumption. The goal of the present study was to investigate whether heavy drinkers with these polymorphisms would respond with

  1. Integrated cannabinoid CB1 receptor transmission within the amygdala-prefrontal cortical pathway modulates neuronal plasticity and emotional memory encoding.

    Science.gov (United States)

    Tan, Huibing; Lauzon, Nicole M; Bishop, Stephanie F; Bechard, Melanie A; Laviolette, Steven R

    2010-06-01

    The cannabinoid CB1 receptor system is functionally involved in the processing and encoding of emotionally salient sensory information, learning and memory. The CB1 receptor is found in high concentrations in brain structures that are critical for emotional processing, including the basolateral amygdala (BLA) and the medial prefrontal cortex (mPFC). In addition, synaptic plasticity in the form of long-term potentiation (LTP) within the BLA > mPFC pathway is an established correlate of exposure to emotionally salient events. We performed a series of in vivo LTP studies by applying tetanic stimulation to the BLA combined with recordings of local field potentials within prelimbic cortical (PLC) region of the rat mPFC. Systemic pretreatment with AM-251 dose dependently blocked LTP along the BLA-PLC pathway and also the behavioral acquisition of conditioned fear memories. We next performed a series of microinfusion experiments wherein CB1 receptor transmission within the BLA > PLC circuit was pharmacologically blocked. Asymmetrical, interhemispheric blockade of CB1 receptor transmission along the BLA > PLC pathway prevented the acquisition of emotionally salient associative memory. Our results indicate that coordinated CB1 receptor transmission within the BLA > PLC pathway is critically involved in the encoding of emotional fear memories and modulates neural plasticity related to the encoding of emotionally salient associative learning.

  2. The interaction between hippocampal GABA-B and cannabinoid receptors upon spatial change and object novelty discrimination memory function.

    Science.gov (United States)

    Nasehi, Mohammad; Alaghmandan-Motlagh, Niyousha; Ebrahimi-Ghiri, Mohaddeseh; Nami, Mohammad; Zarrindast, Mohammad-Reza

    2017-10-01

    Previous studies have postulated functional links between GABA and cannabinoid systems in the hippocampus. The aim of the present study was to investigate any possible interaction between these systems in spatial change and object novelty discrimination memory consolidation in the dorsal hippocampus (CA1 region) of NMRI mice. Assessment of the spatial change and object novelty discrimination memory function was carried out in a non-associative task. The experiment comprised mice exposure to an open field containing five objects followed by the examination of their reactivity to object displacement (spatial change) and object substitution (object novelty) after three sessions of habituation. Our results showed that the post-training intraperitoneal administration of the higher dose of ACPA (0.02 mg/kg) impaired both spatial change and novelty discrimination memory functions. Meanwhile, the higher dose of GABA-B receptor agonist, baclofen, impaired the spatial change memory by itself. Moreover, the post-training intra-CA1 microinjection of a subthreshold dose of baclofen increased the ACPA effect on spatial change and novelty discrimination memory at a lower and higher dose, respectively. On the other hand, the lower and higher but not mid-level doses of GABA-B receptor antagonist, phaclofen, could reverse memory deficits induced by ACPA. However, phaclofen at its mid-level dose impaired the novelty discrimination memory and whereas the higher dose impaired the spatial change memory. Based on our findings, GABA-B receptors in the CA1 region appear to modulate the ACPA-induced cannabinoid CB1 signaling upon spatial change and novelty discrimination memory functions.

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

    Directory of Open Access Journals (Sweden)

    Diana Aguirre-Rueda

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

  4. 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.

  5. Synthesis and biological evaluation of bivalent cannabinoid receptor ligands based on hCB₂R selective benzimidazoles reveal unexpected intrinsic properties.

    Science.gov (United States)

    Nimczick, Martin; Pemp, Daniela; Darras, Fouad H; Chen, Xinyu; Heilmann, Jörg; Decker, Michael

    2014-08-01

    The design of bivalent ligands targeting G protein-coupled receptors (GPCRs) often leads to the development of new, highly selective and potent compounds. To date, no bivalent ligands for the human cannabinoid receptor type 2 (hCB₂R) of the endocannabinoid system (ECS) are described. Therefore, two sets of homobivalent ligands containing as parent structure the hCB2R selective agonist 13a and coupled at different attachment positions were synthesized. Changes of the parent structure at these positions have a crucial effect on the potency and efficacy of the ligands. However, we discovered that bivalency has an influence on the effect at both cannabinoid receptors. Moreover, we found out that the spacer length and the attachment position altered the efficacy of the bivalent ligands at the receptors by turning agonists into antagonists and inverse agonists. Copyright © 2014 Elsevier Ltd. All rights reserved.

  6. Endogenous ligands for C-type lectin receptors: the true regulators of immune homeostasis.

    Science.gov (United States)

    García-Vallejo, Juan J; van Kooyk, Yvette

    2009-07-01

    C-type lectin receptors (CLRs) have long been known as pattern-recognition receptors implicated in the recognition of pathogens by the innate immune system. However, evidence is accumulating that many CLRs are also able to recognize endogenous 'self' ligands and that this recognition event often plays an important role in immune homeostasis. In the present review, we focus on the human and mouse CLRs for which endogenous ligands have been described. Special attention is given to the signaling events initiated upon recognition of the self ligand and the regulation of glycosylation as a switch modulating CLR recognition, and therefore, immune homeostasis.

  7. Biased Agonism of Endogenous Opioid Peptides at the μ-Opioid Receptor.

    Science.gov (United States)

    Thompson, Georgina L; Lane, J Robert; Coudrat, Thomas; Sexton, Patrick M; Christopoulos, Arthur; Canals, Meritxell

    2015-08-01

    Biased agonism is having a major impact on modern drug discovery, and describes the ability of distinct G protein-coupled receptor (GPCR) ligands to activate different cell signaling pathways, and to result in different physiologic outcomes. To date, most studies of biased agonism have focused on synthetic molecules targeting various GPCRs; however, many of these receptors have multiple endogenous ligands, suggesting that "natural" bias may be an unappreciated feature of these GPCRs. The μ-opioid receptor (MOP) is activated by numerous endogenous opioid peptides, remains an attractive therapeutic target for the treatment of pain, and exhibits biased agonism in response to synthetic opiates. The aim of this study was to rigorously assess the potential for biased agonism in the actions of endogenous opioids at the MOP in a common cellular background, and compare these to the effects of the agonist d-Ala2-N-MePhe4-Gly-ol enkephalin (DAMGO). We investigated activation of G proteins, inhibition of cAMP production, extracellular signal-regulated kinase 1 and 2 phosphorylation, β-arrestin 1/2 recruitment, and MOP trafficking, and applied a novel analytical method to quantify biased agonism. Although many endogenous opioids displayed signaling profiles similar to that of DAMGO, α-neoendorphin, Met-enkephalin-Arg-Phe, and the putatively endogenous peptide endomorphin-1 displayed particularly distinct bias profiles. These may represent examples of natural bias if it can be shown that they have different signaling properties and physiologic effects in vivo compared with other endogenous opioids. Understanding how endogenous opioids control physiologic processes through biased agonism can reveal vital information required to enable the design of biased opioids with improved pharmacological profiles and treat diseases involving dysfunction of the endogenous opioid system. Copyright © 2015 by The American Society for Pharmacology and Experimental Therapeutics.

  8. Endogenous GAS6 and Mer receptor signaling regulate prostate cancer stem cells in bone marrow.

    Science.gov (United States)

    Jung, Younghun; Decker, Ann M; Wang, Jingcheng; Lee, Eunsohl; Kana, Lulia A; Yumoto, Kenji; Cackowski, Frank C; Rhee, James; Carmeliet, Peter; Buttitta, Laura; Morgan, Todd M; Taichman, Russell S

    2016-05-03

    GAS6 and its receptors (Tryo 3, Axl, Mer or "TAM") are known to play a role in regulating tumor progression in a number of settings. Previously we have demonstrated that GAS6 signaling regulates invasion, proliferation, chemotherapy-induced apoptosis of prostate cancer (PCa) cells. We have also demonstrated that GAS6 secreted from osteoblasts in the bone marrow environment plays a critical role in establishing prostate tumor cell dormancy. Here we investigated the role that endogenous GAS6 and Mer receptor signaling plays in establishing prostate cancer stem cells in the bone marrow microenvironment.We first observed that high levels of endogenous GAS6 are expressed by disseminated tumor cells (DTCs) in the bone marrow, whereas relatively low levels of endogenous GAS6 are expressed in PCa tumors grown in a s.c. Interestingly, elevated levels of endogenous GAS6 were identified in putative cancer stem cells (CSCs, CD133+/CD44+) compared to non-CSCs (CD133-/CD44-) isolated from PCa/osteoblast cocultures in vitro and in DTCs isolated from the bone marrow 24 hours after intracardiac injection. Moreover, we found that endogenous GAS6 expression is associated with Mer receptor expression in growth arrested (G1) PCa cells, which correlates with the increase of the CSC populations. Importantly, we found that overexpression of GAS6 activates phosphorylation of Mer receptor signaling and subsequent induction of the CSC phenotype in vitro and in vivo.Together these data suggest that endogenous GAS6 and Mer receptor signaling contribute to the establishment of PCa CSCs in the bone marrow microenvironment, which may have important implications for targeting metastatic disease.

  9. 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.

  10. Effect of cannabinoids CB1 receptors blockade on hemodynamic parameters and endothelial function at the immobilization stress in the experiment

    Directory of Open Access Journals (Sweden)

    S. V. Gavreliuk

    2017-12-01

    Full Text Available The aim of the study was to evaluate the response of hemodynamic parameters and changes in endothelial function in modeling of CB1 cannabinoid receptors blockade in chronic stress. Materials and мethods. The study was performed on four groups of hundred-day-old rats, which were examined by ultrasonic scanning during the ten-day period of the experiment. The first group consisted of intact animals; the second group – animals, which were exposed to immobilization stress; the third – animals which were given a solution of rimonabant hydrochloride at the rate of 10 mg×kg-1 of animal weight per day daily per os; the fourth group consisted of animals which daily received a solution of rimonabant hydrochloride at the rate of 10 mg×kg-1 of animal weight per day and were exposed to immobilization stress. The intraluminal vessel diameter, the intima-media complex thickness, endothelium-dependent and endothelium-independent dilation were quantified in the ultrasound examination. Quantitative characteristics of the blood flow were studied: peak systolic velocity, end diastolic velocity, resistive index and peak-systolic/end-diastolic ratio, and estimated mean blood flow velocity. Results. It has been found that the effect of chronic immobilization stress in 100-day-old male rats causes intima-media complex structure and thickness change, endothelial dysfunction and increase in the abdominal aorta intraluminal diameter. Hemodynamics changes are characterized by a decrease in the average blood flow velocity and an increase in the values of indices characterizing the vascular wall peripheral resistance. Prolonged blockade of cannabinoids CB1 receptors leads to endothelial dysfunction development, a decrease in the intraluminal diameter of the abdominal aorta and a decrease in the average blood flow velocity while vascular wall elastic properties maintaining. This affects the sensitivity of cardiovascular system to nitrogen oxide, which is manifested by

  11. Type-1 cannabinoid receptors reduce membrane fluidity of capacitated boar sperm by impairing their activation by bicarbonate.

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    Barbara Barboni

    Full Text Available BACKGROUND: Mammalian spermatozoa acquire their full fertilizing ability (so called capacitation within the female genital tract, where they are progressively exposed to inverse gradients of inhibiting and stimulating molecules. METHODOLOGY/PRINCIPAL FINDINGS: In the present research, the effect on this process of anandamide, an endocannabinoid that can either activate or inhibit cannabinoid receptors depending on its concentration, and bicarbonate, an oviductal activatory molecule, was assessed, in order to study the role exerted by the type 1 cannabinoid receptor (CB1R in the process of lipid membrane remodeling crucial to complete capacitation. To this aim, boar sperm were incubated in vitro under capacitating conditions (stimulated by bicarbonate in the presence or in the absence of methanandamide (Met-AEA, a non-hydrolysable analogue of anandamide. The CB1R involvement was studied by using the specific inhibitor (SR141716 or mimicking its activation by adding a permeable cAMP analogue (8Br-cAMP. By an immunocytochemistry approach it was shown that the Met-AEA inhibits the bicarbonate-dependent translocation of CB1R from the post-equatorial to equatorial region of sperm head. In addition it was found that Met-AEA is able to prevent the bicarbonate-induced increase in membrane disorder and the cholesterol extraction, both preliminary to capacitation, acting through a CB1R-cAMP mediated pathway, as indicated by MC540 and filipin staining, EPR spectroscopy and biochemical analysis on whole membranes (CB1R activity and on membrane enriched fraction (C/P content and anisotropy. CONCLUSIONS/SIGNIFICANCE: Altogether, these data demonstrate that the endocannabinoid system strongly inhibits the process of sperm capacitation, acting as membrane stabilizing agent, thus increasing the basic knowledge on capacitation-related signaling and potentially opening new perspectives in diagnostics and therapeutics of male infertility.

  12. Preclinical and Clinical Assessment of Cannabinoids as Anti-Cancer Agents

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    Daniel A. Ladin

    2016-10-01

    Full Text Available Cancer is the second leading cause of death in the United States with 1.7 million new cases estimated to be diagnosed in 2016. This disease remains a formidable clinical challenge and represents a substantial financial burden to the US health care system. Therefore, research and development of novel therapeutics for the treatment of cancer is of high priority. Cannabinoids and their derivatives have been utilized for their medicinal and therapeutic properties throughout history. Cannabinoid activity is regulated through the endocannabinoid system, which is comprised of cannabinoid receptors, transporters, and enzymes involved in cannabinoid synthesis and breakdown. More recently, cannabinoids have gained special attention for their role in cancer development and reduction. However, many studies investigated these roles using in vitro models which may not adequately mimic tumor growth and metastasis. As such, this article aims to review study results which evaluated effects of cannabinoids from plant, synthetic and endogenous origins on cancer development in preclinical models and to examine the current standing of cannabinoids currently being tested in human cancer patients.

  13. Total soluble and endogenous secretory receptor for advanced glycation endproducts (RAGE) in IBD

    NARCIS (Netherlands)

    Meijer, Berrie; Hoskin, Teagan; Ashcroft, Anna; Burgess, Laura; Keenan, Jacqueline I.; Falvey, James; Gearry, Richard B.; Day, Andrew S.

    2014-01-01

    Recruitment and activation of neutrophils, with release of specific proteins such as S100 proteins, is a feature of inflammatory bowel disease (IBD). Soluble forms of the receptor for advanced glycation endproducts (sRAGE), and variants such as endogenous secretory (esRAGE), can act as decoy

  14. 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

  15. Cannabinoid receptor 2 agonist attenuates pain related behavior in rats with chronic alcohol/high fat diet induced pancreatitis.

    Science.gov (United States)

    Zhang, Liping; Kline, Robert H; McNearney, Terry A; Johnson, Michael P; Westlund, Karin N

    2014-11-17

    Chronic Pancreatitis (CP) is a complex and multifactorial syndrome. Many contributing factors result in development of dysfunctional pain in a significant number of patients. Drugs developed to treat a variety of pain states fall short of providing effective analgesia for patients with chronic pancreatitis, often providing minimal to partial pain relief over time with significant side effects. Recently, availability of selective pharmacological tools has enabled great advances in our knowledge of the role of the cannabinoid receptors in pathophysiology. In particular, cannabinoid receptor 2 (CB2) has emerged as an attractive target for management of chronic pain, as demonstrated in several studies with inflammatory and neuropathic preclinical pain models. In this study, the analgesic efficacy of a novel, highly selective CB2 receptor agonist, LY3038404 HCl, is investigated in a chronic pancreatitis pain model, induced with an alcohol/high fat (AHF) diet. Rats fed the AHF diet developed visceral pain-like behaviors detectable by week 3 and reached a maximum at week 5 that persists as long as the diet is maintained. Rats with AHF induced chronic pancreatitis were treated with LY3038404 HCl (10 mg/kg, orally, twice a day for 9 days). The treated animals demonstrated significantly alleviated pain related behaviors after 3 days of dosing, including increased paw withdrawal thresholds (PWT), prolonged abdominal withdrawal latencies (ABWL), and decreased nocifensive responses to noxious 44°C hotplate stimuli. Terminal histological analysis of pancreatic tissue sections from the AHF chronic pancreatitis animals demonstrated extensive injury, including a global pancreatic gland degeneration (cellular atrophy), vacuolization (fat deposition), and fibrosis. After the LY3038404 HCl treatment, pancreatic tissue was significantly protected from severe damage and fibrosis. LY3038404 HCl affected neither open field exploratory behaviors nor dark/light box preferences as measures

  16. Cannabinoid Receptor 2 Participates in Amyloid-β Processing in a Mouse Model of Alzheimer's Disease but Plays a Minor Role in the Therapeutic Properties of a Cannabis-Based Medicine.

    Science.gov (United States)

    Aso, Ester; Andrés-Benito, Pol; Carmona, Margarita; Maldonado, Rafael; Ferrer, Isidre

    2016-01-01

    The endogenous cannabinoid system represents a promising therapeutic target to modify neurodegenerative pathways linked to Alzheimer's disease (AD). The aim of the present study was to evaluate the specific contribution of CB2 receptor to the progression of AD-like pathology and its role in the positive effect of a cannabis-based medicine (1:1 combination of Δ9-tetrahidrocannabinol and cannabidiol) previously demonstrated to be beneficial in the AβPP/PS1 transgenic model of the disease. A new mouse strain was generated by crossing AβPP/PS1 transgenic mice with CB2 knockout mice. Results show that lack of CB2 exacerbates cortical Aβ deposition and increases the levels of soluble Aβ40. However, CB2 receptor deficiency does not affect the viability of AβPP/PS1 mice, does not accelerate their memory impairment, does not modify tau hyperphosphorylation in dystrophic neurites associated to Aβ plaques, and does not attenuate the positive cognitive effect induced by the cannabis-based medicine in these animals. These findings suggest a minor role for the CB2 receptor in the therapeutic effect of the cannabis-based medicine in AβPP/PS1 mice, but also constitute evidence of a link between CB2 receptor and Aβ processing.

  17. PHARMACOLOGY OF CANNABINOIDS

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    Ilonka Ferjan

    2015-06-01

    Full Text Available The discovery of cannabinoid receptors and endocannabinoid system has led to the potential therapeutic use of cannabis derivatives. Cannabinoids acting through the CB1 receptors modulate the release of other neurotransmitters in central nervous system, whereas the activation of peripheral CB2 receptors results in decreased inflammatory response and increased apoptosis of some tumor cells populations. The cannabinoids have been authorized for chemotherapy-induced nausea and vomiting; stimulation of appetite; to alleviate neuropathic pain and spasticity in multiple sclerosis, and to reduce pain in cancer patients. Efficacy in other diseases and clinical conditions should be proven in ongoing or future clinical trials. Isolation and identification of different cannabinoids from cannabis and synthesis of novel, more selective, derivatives widens their therapeutic potential. However, there are numerous adverse effects reported, especially when cannabinoids formulations with unknown quantitative and qualitative composition are used. Addiction, tolerance, withdrawal symptoms, increased risk of acute myocardial re-infarction, and increased risk of psychosis or worsening of psychosis are the most common adverse effects of cannabinoids. Acute adverse effects e. g. severe central nervous system depression, are more pronounced in children than in adults. Potential cannabinoid medicines should be subject to the same regulations as other potential drugs. Safety and efficacy of any potential drug candidate, regardless whether it is plant-derived or synthesized, should be proven in non-clinical studies and clinical trials, as well as the marketing authorization must be issued by the appropriate drug authority. Patients deserve a quality manufactured product, which always contains the specified amount of "Remedium cardinale."

  18. The Endocannabinoid System, Aggression, and the Violence of Synthetic Cannabinoid Use, Borderline Personality Disorder, Antisocial Personality Disorder, and Other Psychiatric Disorders.

    Science.gov (United States)

    Kolla, Nathan J; Mishra, Achal

    2018-01-01

    Endogenous and exogenous cannabinoids bind to central cannabinoid receptors to control a multitude of behavioral functions, including aggression. The first main objective of this review is to dissect components of the endocannabinoid system, including cannabinoid 1 and cannabinoid 2 receptors; the endogenous cannabinoids anandamide and 2-arachidonoylglycerol; and the indirect cannabinoid modulators fatty acid amide hydrolase and monoacylglycerol lipase; that have shown abnormalities in basic research studies investigating mechanisms of aggression. While most human research has concluded that the active ingredient of marijuana, Δ9-tetrahydrocannabinol, tends to dampen rather than provoke aggression in acute doses, recent evidence supports a relationship between the ingestion of synthetic cannabinoids and emergence of violent or aggressive behavior. Thus, another objective is to evaluate the emerging clinical data. This paper also discusses the relationship between prenatal and perinatal exposure to cannabis as well as use of cannabis in adolescence on aggressive outcomes. A final objective of the paper is to discuss endocannabinoid abnormalities in psychotic and affective disorders, as well as clinically aggressive populations, such as borderline personality disorder and antisocial personality disorder. With regard to the former condition, decreased anandamide metabolites have been reported in the cerebrospinal fluid, while some preliminary evidence suggests that fatty acid amide hydrolase genetic polymorphisms are linked to antisocial personality disorder and impulsive-antisocial psychopathic traits. To summarize, this paper will draw upon basic and clinical research to explain how the endocannabinoid system may contribute to the genesis of aggressive behavior.

  19. The Endocannabinoid System, Aggression, and the Violence of Synthetic Cannabinoid Use, Borderline Personality Disorder, Antisocial Personality Disorder, and Other Psychiatric Disorders

    Directory of Open Access Journals (Sweden)

    Nathan J. Kolla

    2018-03-01

    Full Text Available Endogenous and exogenous cannabinoids bind to central cannabinoid receptors to control a multitude of behavioral functions, including aggression. The first main objective of this review is to dissect components of the endocannabinoid system, including cannabinoid 1 and cannabinoid 2 receptors; the endogenous cannabinoids anandamide and 2-arachidonoylglycerol; and the indirect cannabinoid modulators fatty acid amide hydrolase and monoacylglycerol lipase; that have shown abnormalities in basic research studies investigating mechanisms of aggression. While most human research has concluded that the active ingredient of marijuana, Δ9-tetrahydrocannabinol, tends to dampen rather than provoke aggression in acute doses, recent evidence supports a relationship between the ingestion of synthetic cannabinoids and emergence of violent or aggressive behavior. Thus, another objective is to evaluate the emerging clinical data. This paper also discusses the relationship between prenatal and perinatal exposure to cannabis as well as use of cannabis in adolescence on aggressive outcomes. A final objective of the paper is to discuss endocannabinoid abnormalities in psychotic and affective disorders, as well as clinically aggressive populations, such as borderline personality disorder and antisocial personality disorder. With regard to the former condition, decreased anandamide metabolites have been reported in the cerebrospinal fluid, while some preliminary evidence suggests that fatty acid amide hydrolase genetic polymorphisms are linked to antisocial personality disorder and impulsive-antisocial psychopathic traits. To summarize, this paper will draw upon basic and clinical research to explain how the endocannabinoid system may contribute to the genesis of aggressive behavior.

  20. Chronic and acute adenosine A2A receptor blockade prevents long-term episodic memory disruption caused by acute cannabinoid CB1 receptor activation.

    Science.gov (United States)

    Mouro, Francisco M; Batalha, Vânia L; Ferreira, Diana G; Coelho, Joana E; Baqi, Younis; Müller, Christa E; Lopes, Luísa V; Ribeiro, Joaquim A; Sebastião, Ana M

    2017-05-01

    Cannabinoid-mediated memory impairment is a concern in cannabinoid-based therapies. Caffeine exacerbates cannabinoid CB 1 receptor (CB 1 R)-induced memory deficits through an adenosine A 1 receptor-mediated mechanism. We now evaluated how chronic or acute blockade of adenosine A 2A receptors (A 2A Rs) affects long-term episodic memory deficits induced by a single injection of a selective CB 1 R agonist. Long-term episodic memory was assessed by the novel object recognition (NOR) test. Mice received an intraperitoneal (i.p.) injection of the CB 1 /CB 2 receptor agonist WIN 55,212-2 (1 mg/kg) immediately after the NOR training, being tested for novelty recognition 24 h later. Anxiety levels were assessed by the Elevated Plus Maze test, immediately after the NOR. Mice were also tested for exploratory behaviour at the Open Field. For chronic A 2A R blockade, KW-6002 (istradefylline) (3 mg/kg/day) was administered orally for 30 days; acute blockade of A 2A Rs was assessed by i.p. injection of SCH 58261 (1 mg/kg) administered either together with WIN 55,212-2 or only 30 min before the NOR test phase. The involvement of CB 1 Rs was assessed by using the CB 1 R antagonist, AM251 (3 mg/kg, i.p.). WIN 55,212-2 caused a disruption in NOR, an action absent in mice also receiving AM251, KW-6002 or SCH 58261 during the encoding/consolidation phase; SCH 58251 was ineffective if present during retrieval only. No effects were detected in the Elevated Plus maze or Open Field Test. The finding that CB 1 R-mediated memory disruption is prevented by antagonism of adenosine A 2A Rs, highlights a possibility to prevent cognitive side effects when therapeutic application of CB 1 R drugs is desired. Copyright © 2017 Elsevier Ltd. All rights reserved.

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

    Science.gov (United States)

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

    2012-03-01

    We have recently reported that early maternal deprivation (MD) for 24 h [postnatal day (PND) 9-10] and/or an adolescent chronic treatment with the cannabinoid agonist CP-55,940 (CP) [0.4 mg/kg, PND 28-42] in Wistar rats induced, in adulthood, diverse sex-dependent long-term behavioral and physiological modifications. Here we show the results obtained from investigating the immunohistochemical analysis of CB1 cannabinoid receptors, glial fibrillary acidic protein (GFAP) positive (+) cells and brain-derived neurotrophic factor (BDNF) expression in the hippocampus of the same animals. MD induced, in males, a significant increase in the number of GFAP+ cells in CA1 and CA3 areas and in the polymorphic layer of the dentate gyrus (DG), an effect that was attenuated by CP in the two latter regions. Adolescent cannabinoid exposure induced, in control non-deprived males, a significant increase in the number of GFAP+ cells in the polymorphic layer of the DG. MD induced a decrease in CB1 expression in both sexes, and this effect was reversed in males by the cannabinoid treatment. In turn, the drug "per se" induced, in males, a general decrease in CB1 immunoreactivity, and the opposite effect was observed in females. Cannabinoid exposure tended to reduce BDNF expression in CA1 and CA3 of females, whereas MD counteracted this trend and induced an increase of BDNF in females. As a whole, the present results show sex-dependent long-term effects of both MD and juvenile cannabinoid exposure as well as functional interactions between the two treatments. Copyright © 2011 IBRO. Published by Elsevier Ltd. All rights reserved.

  2. MATERNAL DEPRIVATION AND ADOLESCENT CANNABINOID EXPOSURE IMPACT HIPPOCAMPAL ASTROCYTES, CB1 RECEPTORS AND BRAIN-DERIVED NEUROTROPHIC FACTOR IN A SEXUALLY DIMORPHIC FASHION

    Science.gov (United States)

    LÓPEZ-GALLARDO, M.; LÓPEZ-RODRÍGUEZ, A. B.; LLORENTE-BERZAL, Á.; ROTLLANT, D.; MACKIE, K.; ARMARIO, A.; NADAL, R.; VIVEROS, M.-P.

    2013-01-01

    We have recently reported that early maternal deprivation (MD) for 24 h [postnatal day (PND) 9–10] and/or an adolescent chronic treatment with the cannabinoid agonist CP-55,940 (CP) [0.4 mg/kg, PND 28–42] in Wistar rats induced, in adulthood, diverse sex-dependent long-term behavioral and physiological modifications. Here we show the results obtained from investigating the immunohistochemical analysis of CB1 cannabinoid receptors, glial fibrillary acidic protein (GFAP) positive (+) cells and brain-derived neurotrophic factor (BDNF) expression in the hippocampus of the same animals. MD induced, in males, a significant increase in the number of GFAP+ cells in CA1 and CA3 areas and in the polymorphic layer of the dentate gyrus (DG), an effect that was attenuated by CP in the two latter regions. Adolescent cannabinoid exposure induced, in control non-deprived males, a significant increase in the number of GFAP+ cells in the polymorphic layer of the DG. MD induced a decrease in CB1 expression in both sexes, and this effect was reversed in males by the cannabinoid treatment. In turn, the drug “per se” induced, in males, a general decrease in CB1 immunoreactivity, and the opposite effect was observed in females. Cannabinoid exposure tended to reduce BDNF expression in CA1 and CA3 of females, whereas MD counteracted this trend and induced an increase of BDNF in females. As a whole, the present results show sex-dependent long-term effects of both MD and juvenile cannabinoid exposure as well as functional interactions between the two treatments. PMID:22001306

  3. Endogenous activation of adenosine A(1) receptors accelerates ischemic suppression of spontaneous electrocortical activity

    DEFF Research Database (Denmark)

    Ilie, Andrei; Ciocan, Dragos; Zagrean, Ana-Maria

    2006-01-01

    Cerebral ischemia induces a rapid suppression of spontaneous brain rhythms prior to major alterations in ionic homeostasis. It was found in vitro during ischemia that the rapidly formed adenosine, resulting from the intracellular breakdown of ATP, may inhibit synaptic transmission via the A(1......) receptor subtype. The link between endogenous A(1) receptor activation during ischemia and the suppression of spontaneous electrocortical activity has not yet been established in the intact brain. The aim of this study was to investigate in vivo the effects of A(1) receptor antagonism by 8-cyclopentyl-1...

  4. Platelet alpha-2 adrenergic receptor-mediated phosphoinositide responses in endogenous depression

    International Nuclear Information System (INIS)

    Mori, Hideki; Koyama, Tsukasa; Yamashita, Itaru

    1991-01-01

    We have previously indicated that epinephrine stimulates phosphoinositide (PI) hydrolysis by activating alpha-2 adrenergic receptors in human platelets. This method involves the measurement of the accumulation of [ 3 H]-inositol-1-phosphate (IP-1) as an index of Pl hydrolysis; lithium is added to inhibit the metabolism of IP-1, thus giving an enhanced signal. In the present study, we assessed the platelet alpha-2 adrenergic receptor-mediated PI responses in samples from 15 unmedicated patients with endogenous depression and 15 age- and sex-matched control subjects. The responses to epinephrine in the depressed patients were significantly higher than those of the controls, whereas the basal values did not differ significantly. These results support the hypothesis that platelet alpha-2 adrenergic receptors may be supersensitive in patients with endogenous depression

  5. 1-Methyl-beta-carboline (harmane), a potent endogenous inhibitor of benzodiazepine receptor binding.

    Science.gov (United States)

    Rommelspacher, H; Nanz, C; Borbe, H O; Fehske, K J; Müller, W E; Wollert, U

    1980-10-01

    The interaction of several beta-carbolines with specific [3H]-flunitrazepam binding to benzodiazepine receptors in rat brain membranes was investigated. Out of the investigated compounds, harmane and norharmane were the most potent inhibitors of specific [3H]-flunitrazepam binding, with IC50-values in the micromolar range. All other derivatives, including harmine, harmaline, and several tetrahydroderivatives were at least ten times less potent. Harmane has been previously found in rat brain and human urine, so it is the most potent endogenous inhibitor of specific [3H]-flunitrazepam binding known so far, with a several fold higher affinity for the benzodiazepine receptor than inosine and hypoxanthine. Thus, we suggest that harmane or other related beta-carbolines could be potential candidates as endogenous ligands of the benzodiazepine receptor.

  6. Biased Type 1 Cannabinoid Receptor Signaling Influences Neuronal Viability in a Cell Culture Model of Huntington Disease.

    Science.gov (United States)

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

    2016-03-01

    Huntington disease (HD) is an inherited, autosomal dominant, neurodegenerative disorder with limited treatment options. Prior to motor symptom onset or neuronal cell loss in HD, levels of the type 1 cannabinoid receptor (CB1) decrease in the basal ganglia. Decreasing CB1 levels are strongly correlated with chorea and cognitive deficit. CB1 agonists are functionally selective (biased) for divergent signaling pathways. In this study, six cannabinoids were tested for signaling bias in in vitro models of medium spiny projection neurons expressing wild-type (STHdh(Q7/Q7)) or mutant huntingtin protein (STHdh(Q111/Q111)). Signaling bias was assessed using the Black and Leff operational model. Relative activity [ΔlogR (τ/KA)] and system bias (ΔΔlogR) were calculated relative to the reference compound WIN55,212-2 for Gαi/o, Gαs, Gαq, Gβγ, and β-arrestin1 signaling following treatment with 2-arachidonoylglycerol (2-AG), anandamide (AEA), CP55,940, Δ(9)-tetrahydrocannabinol (THC), cannabidiol (CBD), and THC+CBD (1:1), and compared between wild-type and HD cells. The Emax of Gαi/o-dependent extracellular signal-regulated kinase (ERK) signaling was 50% lower in HD cells compared with wild-type cells. 2-AG and AEA displayed Gαi/o/Gβγ bias and normalized CB1 protein levels and improved cell viability, whereas CP55,940 and THC displayed β-arrestin1 bias and reduced CB1 protein levels and cell viability in HD cells. CBD was not a CB1 agonist but inhibited THC-dependent signaling (THC+CBD). Therefore, enhancing Gαi/o-biased endocannabinoid signaling may be therapeutically beneficial in HD. In contrast, cannabinoids that are β-arrestin-biased--such as THC found at high levels in modern varieties of marijuana--may be detrimental to CB1 signaling, particularly in HD where CB1 levels are already reduced. Copyright © 2016 by The American Society for Pharmacology and Experimental Therapeutics.

  7. Phencyclidine-Induced Social Withdrawal Results from Deficient Stimulation of Cannabinoid CB1 Receptors: Implications for Schizophrenia

    Science.gov (United States)

    Seillier, Alexandre; Martinez, Alex A; Giuffrida, Andrea

    2013-01-01

    The neuronal mechanisms underlying social withdrawal, one of the core negative symptoms of schizophrenia, are not well understood. Recent studies suggest an involvement of the endocannabinoid system in the pathophysiology of schizophrenia and, in particular, of negative symptoms. We used biochemical, pharmacological, and behavioral approaches to investigate the role played by the endocannabinoid system in social withdrawal induced by sub-chronic administration of phencyclidine (PCP). Pharmacological enhancement of endocannabinoid levels via systemic administration of URB597, an inhibitor of endocannabinoid degradation, reversed social withdrawal in PCP-treated rats via stimulation of CB1 receptors, but reduced social interaction in control animals through activation of a cannabinoid/vanilloid-sensitive receptor. In addition, the potent CB agonist CP55,940 reversed PCP-induced social withdrawal in a CB1-dependent manner, whereas pharmacological blockade of CB1 receptors by either AM251 or SR141716 reduced the time spent in social interaction in control animals. PCP-induced social withdrawal was accompanied by a decrease of anandamide (AEA) levels in the amygdala and prefrontal cortex, and these deficits were reversed by URB597. As CB1 receptors are predominantly expressed on GABAergic interneurons containing the anxiogenic peptide cholecystokinin (CCK), we also examined whether the PCP-induced social withdrawal resulted from deficient CB1-mediated modulation of CCK transmission. The selective CCK2 antagonist LY225910 blocked both PCP- and AM251-induced social withdrawal, but not URB597 effect in control rats. Taken together, these findings indicate that AEA-mediated activation of CB1 receptors is crucial for social interaction, and that PCP-induced social withdrawal results from deficient endocannabinoid transmission. PMID:23563893

  8. Singular Location and Signaling Profile of Adenosine A2A-Cannabinoid CB1 Receptor Heteromers in the Dorsal Striatum.

    Science.gov (United States)

    Moreno, Estefanía; Chiarlone, Anna; Medrano, Mireia; Puigdellívol, Mar; Bibic, Lucka; Howell, Lesley A; Resel, Eva; Puente, Nagore; Casarejos, María J; Perucho, Juan; Botta, Joaquín; Suelves, Nuria; Ciruela, Francisco; Ginés, Silvia; Galve-Roperh, Ismael; Casadó, Vicent; Grandes, Pedro; Lutz, Beat; Monory, Krisztina; Canela, Enric I; Lluís, Carmen; McCormick, Peter J; Guzmán, Manuel

    2018-04-01

    The dorsal striatum is a key node for many neurobiological processes such as motor activity, cognitive functions, and affective processes. The proper functioning of striatal neurons relies critically on metabotropic receptors. Specifically, the main adenosine and endocannabinoid receptors present in the striatum, ie, adenosine A 2A receptor (A 2A R) and cannabinoid CB 1 receptor (CB 1 R), are of pivotal importance in the control of neuronal excitability. Facilitatory and inhibitory functional interactions between striatal A 2A R and CB 1 R have been reported, and evidence supports that this cross-talk may rely, at least in part, on the formation of A 2A R-CB 1 R heteromeric complexes. However, the specific location and properties of these heteromers have remained largely unknown. Here, by using techniques that allowed a precise visualization of the heteromers in situ in combination with sophisticated genetically modified animal models, together with biochemical and pharmacological approaches, we provide a high-resolution expression map and a detailed functional characterization of A 2A R-CB 1 R heteromers in the dorsal striatum. Specifically, our data unveil that the A 2A R-CB 1 R heteromer (i) is essentially absent from corticostriatal projections and striatonigral neurons, and, instead, is largely present in striatopallidal neurons, (ii) displays a striking G protein-coupled signaling profile, where co-stimulation of both receptors leads to strongly reduced downstream signaling, and (iii) undergoes an unprecedented dysfunction in Huntington's disease, an archetypal disease that affects striatal neurons. Altogether, our findings may open a new conceptual framework to understand the role of coordinated adenosine-endocannabinoid signaling in the indirect striatal pathway, which may be relevant in motor function and neurodegenerative diseases.

  9. Anandamide induces matrix metalloproteinase-2 production through cannabinoid-1 receptor and transient receptor potential vanilloid-1 in human dental pulp cells in culture.

    Science.gov (United States)

    Miyashita, Keiko; Oyama, Tohru; Sakuta, Tetsuya; Tokuda, Masayuki; Torii, Mitsuo

    2012-06-01

    Anandamide (N-arachidonoylethanolamine [AEA]) is one of the main endocannabinoids. Endocannabinoids are implicated in various physiological and pathologic functions, inducing not only nociception but also regeneration and inflammation. The role of the endocannabinoid system in peripheral organs was recently described. The aim of this study was to investigate the effect of AEA on matrix metalloproteinase (MMP)-2 induction in human dental pulp cells (HPC). We examined AEA-induced MMP-2 production and the expression of AEA receptors (cannabinoid [CB] receptor-1, CB2, and transient receptor potential vanilloid-1 [TRPV1]) in HPC by Western blot. MMP-2 concentrations in supernatants were determined by enzyme-linked immunosorbent assay. We then investigated the role of the AEA receptors and mitogen-activated protein kinase in AEA-induced MMP-2 production in HPC. AEA significantly induced MMP-2 production in HPC. HPC expressed all 3 types of AEA receptor (CB1, CB2, and TRPV1). AEA-induced MMP-2 production was blocked by CB1 or TRPV1 antagonists and by small interfering RNA for CB1 or TRPV1. Furthermore, c-Jun N-terminal kinase inhibitor also reduced MMP-2 production. We demonstrated for the first time that AEA induced MMP-2 production via CB1 and TRPV1 in HPC. Copyright © 2012 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

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

    Directory of Open Access Journals (Sweden)

    David J Marcus

    Full Text Available 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.

  11. Cannabinoid CB1 receptors in distinct circuits of the extended amygdala determine fear responsiveness to unpredictable threat.

    Science.gov (United States)

    Lange, M D; Daldrup, T; Remmers, F; Szkudlarek, H J; Lesting, J; Guggenhuber, S; Ruehle, S; Jüngling, K; Seidenbecher, T; Lutz, B; Pape, H C

    2017-10-01

    The brain circuits underlying behavioral fear have been extensively studied over the last decades. Although the vast majority of experimental studies assess fear as a transient state of apprehension in response to a discrete threat, such phasic states of fear can shift to a sustained anxious apprehension, particularly in face of diffuse cues with unpredictable environmental contingencies. Unpredictability, in turn, is considered an important variable contributing to anxiety disorders. The networks of the extended amygdala have been suggested keys to the control of phasic and sustained states of fear, although the underlying synaptic pathways and mechanisms remain poorly understood. Here, we show that the endocannabinoid system acting in synaptic circuits of the extended amygdala can explain the fear response profile during exposure to unpredictable threat. Using fear training with predictable or unpredictable cues in mice, combined with local and cell-type-specific deficiency and rescue of cannabinoid type 1 (CB1) receptors, we found that presynaptic CB1 receptors on distinct amygdala projections to bed nucleus of the stria terminalis (BNST) are both necessary and sufficient for the shift from phasic to sustained fear in response to an unpredictable threat. These results thereby identify the causal role of a defined protein in a distinct brain pathway for the temporal development of a sustained state of anxious apprehension during unpredictability of environmental influences, reminiscent of anxiety symptoms in humans.

  12. Cannabinoid 2 Receptor Agonist Improves Systemic Sensitivity to Insulin in High-Fat Diet/Streptozotocin-Induced Diabetic Mice

    Directory of Open Access Journals (Sweden)

    Xiuyuan Zhang

    2016-12-01

    Full Text Available Background/Aims: The endocannabinoid signalling (ECS system has been known to regulate glucose homeostasis. Previous studies have suggested that the cannabinoid 2 (CB2 receptor may play a regulatory role on insulin secretion, immune modulation and insulin resistance. Given that diabetes and insulin resistance are attributable to elevated inflammatory tone, we investigated the role of CB2 receptor on glucose tolerance and insulin sensitivity in high-fat diet (HFD/streptozotocin (STZ-induced mice. Methods: Diabetes was induced in male ICR mice by HFD/STZ and exposed to a CB2 receptor agonist, SER601, for 2- or 4-weeks via subcutaneous implantation of osmotic minipumps. Glucose and insulin tolerance tests were performed at the end of treatment. Islets were isolated for assessment of β-cell function. Pancreases and skeletal muscles were also obtained for histological analyses. Results: Despite a lack of impact on glucose tolerance, substantial improvement on insulin sensitivity was observed in SER601-treated mice, which could partly be attributed to improved islet β-cell function, shown as increased glucose-induced insulin secretion and insulin content. No changes on islet macrophage infiltration or skeletal muscle fat deposition were detectable from SER601-treated mice. However, a major decrease in body weight was recorded at the end of 4-week SER601 exposure, accompanied by a lack of epididymal adipose mass in SER601-treated mice. Conclusion: Our data suggest a lipolytic role of SER601 in HFD/STZ-induced diabetic mice, which results in significant improvement of systemic insulin sensitivity. Thus, the CB2 receptor may be considered a promising target for therapeutic development against insulin resistance and obesity-related diabetes.

  13. Biodistribution and dosimetry in humans of two inverse agonists to image cannabinoid CB1 receptors using positron emission tomography

    International Nuclear Information System (INIS)

    Terry, Garth E.; Hirvonen, Jussi; Liow, Jeih-San; Seneca, Nicholas; Morse, Cheryl L.; Pike, Victor W.; Innis, Robert B.; Tauscher, Johannes T.; Schaus, John M.; Phebus, Lee; Felder, Christian C.; Halldin, Christer

    2010-01-01

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

  14. Shotgun glycomics of pig lung identifies natural endogenous receptors for influenza viruses.

    Science.gov (United States)

    Byrd-Leotis, Lauren; Liu, Renpeng; Bradley, Konrad C; Lasanajak, Yi; Cummings, Sandra F; Song, Xuezheng; Heimburg-Molinaro, Jamie; Galloway, Summer E; Culhane, Marie R; Smith, David F; Steinhauer, David A; Cummings, Richard D

    2014-06-03

    Influenza viruses bind to host cell surface glycans containing terminal sialic acids, but as studies on influenza binding become more sophisticated, it is becoming evident that although sialic acid may be necessary, it is not sufficient for productive binding. To better define endogenous glycans that serve as viral receptors, we have explored glycan recognition in the pig lung, because influenza is broadly disseminated in swine, and swine have been postulated as an intermediary host for the emergence of pandemic strains. For these studies, we used the technology of "shotgun glycomics" to identify natural receptor glycans. The total released N- and O-glycans from pig lung glycoproteins and glycolipid-derived glycans were fluorescently tagged and separated by multidimensional HPLC, and individual glycans were covalently printed to generate pig lung shotgun glycan microarrays. All viruses tested interacted with one or more sialylated N-glycans but not O-glycans or glycolipid-derived glycans, and each virus demonstrated novel and unexpected differences in endogenous N-glycan recognition. The results illustrate the repertoire of specific, endogenous N-glycans of pig lung glycoproteins for virus recognition and offer a new direction for studying endogenous glycan functions in viral pathogenesis.

  15. 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.

  16. 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)

    Casteels, Cindy; Martinez, Emili; Camon, Lluisa; Vera, Nuria de; Planas, Anna M.; Bormans, Guy; Baekelandt, Veerle; Laere, Koen van

    2010-01-01

    Several lines of evidence imply early alterations in metabolic, dopaminergic and endocannabinoid neurotransmission in Huntington's disease (HD). Using [ 18 F]MK-9470 and small animal PET, we investigated cerebral changes in type 1 cannabinoid (CB 1 ) receptor binding in the quinolinic acid (QA) rat model of HD in relation to glucose metabolism, dopamine D 2 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 [ 18 F]MK-9470, [ 18 F]FDG and [ 11 C]raclopride. Relative glucose metabolism and parametric CB 1 receptor and D 2 binding images were anatomically standardized to Paxinos space and analysed voxel-wise using Statistical Parametric Mapping (SPM2). In the QA model, [ 18 F]MK-9470 uptake, glucose metabolism and D 2 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 ). [ 18 F]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 CB 1 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 CB 1 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, D 2 and CB 1 neurotransmission in the contralateral hemisphere. (orig.)

  17. Paradoxical effects of the cannabinoid CB2 receptor agonist GW405833 on rat osteoarthritic knee joint pain.

    Science.gov (United States)

    Schuelert, N; Zhang, C; Mogg, A J; Broad, L M; Hepburn, D L; Nisenbaum, E S; Johnson, M P; McDougall, J J

    2010-11-01

    The present study examined whether local administration of the cannabinoid-2 (CB(2)) receptor agonist GW405833 could modulate joint nociception in control rat knee joints and in an animal model of osteoarthritis (OA). OA was induced in male Wistar rats by intra-articular injection of sodium monoiodo-acetate with a recovery period of 14 days. Immunohistochemistry was used to evaluate the expression of CB(2) and transient receptor potential vanilloid channel-1 (TRPV1) receptors in the dorsal root ganglion (DRG) and synovial membrane of sham- and sodium mono-iodoacetate (MIA)-treated animals. Electrophysiological recordings were made from knee joint primary afferents in response to rotation of the joint both before and following close intra-arterial injection of different doses of GW405833. The effect of intra-articular GW405833 on joint pain perception was determined by hindlimb incapacitance. An in vitro neuronal release assay was used to see if GW405833 caused release of an inflammatory neuropeptide (calcitonin gene-related peptide - CGRP). CB(2) and TRPV1 receptors were co-localized in DRG neurons and synoviocytes in both sham- and MIA-treated animals. Local application of the GW405833 significantly reduced joint afferent firing rate by up to 31% in control knees. In OA knee joints, however, GW405833 had a pronounced sensitising effect on joint mechanoreceptors. Co-administration of GW405833 with the CB(2) receptor antagonist AM630 or pre-administration of the TRPV1 ion channel antagonist SB366791 attenuated the sensitising effect of GW405833. In the pain studies, intra-articular injection of GW405833 into OA knees augmented hindlimb incapacitance, but had no effect on pain behaviour in saline-injected control joints. GW405833 evoked increased CGRP release via a TRPV1 channel-dependent mechanism. These data indicate that GW405833 reduces the mechanosensitivity of afferent nerve fibres in control joints but causes nociceptive responses in OA joints. The observed

  18. [The endogenous opioid system and drug addiction].

    Science.gov (United States)

    Maldonado, R

    2010-01-01

    Drug addiction is a chronic brain disorder leading to complex adaptive changes within the brain reward circuits. Several neurotransmitters, including the endogenous opioid system are involved in these changes. The opioid system plays a pivotal role in different aspects of addiction. Thus, opioid receptors and endogenous opioid peptides are largely distributed in the mesolimbic system and modulate dopaminergic activity within the reward circuits. Opioid receptors and peptides are selectively involved in several components of the addictive processes induced by opioids, cannabinoids, psychostimulants, alcohol and nicotine. This review is focused on the contribution of each component of the endogenous opioid system in the addictive properties of the different drugs of abuse. Copyright 2010 Elsevier Masson SAS. All rights reserved.

  19. Peripheral-type benzodiazepine receptor: a protein of mitochondrial outer membranes utilizing porphyrins as endogenous ligands

    International Nuclear Information System (INIS)

    Snyder, S.H.; Verma, A.; Trifiletti, R.R.

    1987-01-01

    The peripheral-type benzodiazepine receptor is a site identified by its nanomolar affinity for [ 3 H]diazepam, similar to the affinity of diazepam for the central-type benzodiazepine receptor in the brain. The peripheral type benzodiazepine receptor occurs in many peripheral tissues but has discrete localizations as indicated by autoradiographic studies showing uniquely high densities of the receptors in the adrenal cortex and in Leydig cells of the testes. Subcellular localization studies reveal a selective association of the receptors with the outer membrane of mitochondria. Photoaffinity labeling of the mitochondrial receptor with [ 3 H]flunitrazepam reveals two discrete labeled protein bands of 30 and 35 kDa, respectively. The 35-kDa band appears to be identical with the voltage-dependent anion channel protein porin. Fractionation of numerous peripheral tissues reveals a single principal endogenous ligand for the receptor, consisting of porphyrins, which display nanomolar affinity. Interactions of porphyrins with the mitochondrial receptor may clarify its physiological role and account for many pharmacological actions of benzodiazepines

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

    OpenAIRE

    Casteels, Cindy; Koole, Michel; Celen, Sofie; Bormans, Guy; Van Laere, Koen

    2012-01-01

    PURPOSE: [(18)F]MK-9470 is an inverse agonist for the type 1 cannabinoid (CB1) receptor allowing its use in PET imaging. We characterized the kinetics of [(18)F]MK-9470 and evaluated its ability to quantify CB1 receptor availability in the rat brain. METHODS: Dynamic small-animal PET scans with [(18)F]MK-9470 were performed in Wistar rats on a FOCUS-220 system for up to 10 h. Both plasma and perfused brain homogenates were analysed using HPLC to quantify radiometabolites. Displacement and blo...

  1. A variant on promoter of the cannabinoid receptor 1 gene (CNR1) moderates the effect of valence on working memory.

    Science.gov (United States)

    Fairfield, Beth; Mammarella, Nicola; Franzago, Marica; Di Domenico, Alberto; Stuppia, Liborio; Gatta, Valentina

    2018-02-01

    Cannabinoid receptor 1 gene (CNR1) variants have been related to affective information processing and, in particular, to stress release. Here, we aimed to examine whether the endocannabinoid system via CNR1 signaling modulates affective working memory, the memory system that transiently maintains and manipulates emotionally charged material. We focused on rs2180619 (A > G) polymorphism and examined genotype data collected from 231 healthy females. Analyses showed how a general positivity bias in working memory (i.e., better memory for positive words) emerged as task strings lengthened only in carriers of the major allele (AA/AG). Differently, GG carriers showed better memory for affective items in general (i.e., positive and negative words). These findings are some of the first to directly highlight the role of variant on promoter of the CNR1 gene in affective working memory and to evidence a differentiation among CNR1 genotypes in terms of larger difficulties in disengaging from negative stimuli in GG carriers.

  2. Developmental and visual input-dependent regulation of the CB1 cannabinoid receptor in the mouse visual cortex.

    Directory of Open Access Journals (Sweden)

    Taisuke Yoneda

    Full Text Available The mammalian visual system exhibits significant experience-induced plasticity in the early postnatal period. While physiological studies have revealed the contribution of the CB1 cannabinoid receptor (CB1 to developmental plasticity in the primary visual cortex (V1, it remains unknown whether the expression and localization of CB1 is regulated during development or by visual experience. To explore a possible role of the endocannabinoid system in visual cortical plasticity, we examined the expression of CB1 in the visual cortex of mice. We found intense CB1 immunoreactivity in layers II/III and VI. CB1 mainly localized at vesicular GABA transporter-positive inhibitory nerve terminals. The amount of CB1 protein increased throughout development, and the specific laminar pattern of CB1 appeared at P20 and remained until adulthood. Dark rearing from birth to P30 decreased the amount of CB1 protein in V1 and altered the synaptic localization of CB1 in the deep layer. Dark rearing until P50, however, did not influence the expression of CB1. Brief monocular deprivation for 2 days upregulated the localization of CB1 at inhibitory nerve terminals in the deep layer. Taken together, the expression and the localization of CB1 are developmentally regulated, and both parameters are influenced by visual experience.

  3. A cell population that strongly expresses the CB1 cannabinoid receptor in the ependyma of the rat spinal cord.

    Science.gov (United States)

    Garcia-Ovejero, Daniel; Arevalo-Martin, Angel; Paniagua-Torija, Beatriz; Sierra-Palomares, Yolanda; Molina-Holgado, Eduardo

    2013-01-01

    The cells surrounding the central canal of the spinal cord are a source of stem/precursor cells that may give rise to neurons, astrocytes, or oligodendrocytes. However, they are a heterogeneous population that remains poorly understood. Here we describe a subpopulation characterized by their strong expression of the CB(1) cannabinoid receptor, oval/round soma, apical nucleus, a variable number of cilia (0, 1, or 2), and the presence of a single short and occasionally ramified basal process. These cells are mainly located in the lateral and dorsal central canal throughout the spinal cord. These CB(1)(HIGH) cells are closely related to the basal lamina labyrinths or fractones derived from subependymal microglia. In addition, CB(1)(HIGH) cells express some stem/precursor cell markers, including vimentin, nestin, Sox2, Sox9, and GLAST, but not others such as CD15 or GFAP. In addition, this cell population does not proliferate in the intact adult spinal cord, although up to 50% of these cells express the proliferation marker Ki67 in newly born rats or after a spinal cord contusion. The present findings contribute to our understanding of the spinal cord central canal structure and reveal the targets for endocannabinoids inside this neurogenic niche. Copyright © 2012 Wiley Periodicals, Inc.

  4. Novel endogenous N-acyl amides activate TRPV1-4 receptors, BV-2 microglia, and are regulated in brain in an acute model of inflammation

    Science.gov (United States)

    Raboune, Siham; Stuart, Jordyn M.; Leishman, Emma; Takacs, Sara M.; Rhodes, Brandon; Basnet, Arjun; Jameyfield, Evan; McHugh, Douglas; Widlanski, Theodore; Bradshaw, Heather B.

    2014-01-01

    A family of endogenous lipids, structurally analogous to the endogenous cannabinoid, N-arachidonoyl ethanolamine (Anandamide), and called N-acyl amides have emerged as a family of biologically active compounds at TRP receptors. N-acyl amides are constructed from an acyl group and an amine via an amide bond. This same structure can be modified by changing either the fatty acid or the amide to form potentially hundreds of lipids. More than 70 N-acyl amides have been identified in nature. We have ongoing studies aimed at isolating and characterizing additional members of the family of N-acyl amides in both central and peripheral tissues in mammalian systems. Here, using a unique in-house library of over 70 N-acyl amides we tested the following three hypotheses: (1) Additional N-acyl amides will have activity at TRPV1-4, (2) Acute peripheral injury will drive changes in CNS levels of N-acyl amides, and (3) N-acyl amides will regulate calcium in CNS-derived microglia. Through these studies, we have identified 20 novel N-acyl amides that collectively activate (stimulating or inhibiting) TRPV1-4. Using lipid extraction and HPLC coupled to tandem mass spectrometry we showed that levels of at least 10 of these N-acyl amides that activate TRPVs are regulated in brain after intraplantar carrageenan injection. We then screened the BV2 microglial cell line for activity with this N-acyl amide library and found overlap with TRPV receptor activity as well as additional activators of calcium mobilization from these lipids. Together these data provide new insight into the family of N-acyl amides and their roles as signaling molecules at ion channels, in microglia, and in the brain in the context of inflammation. PMID:25136293

  5. Cannabinoid receptor-mediated disruption of sensory gating and neural oscillations: A translational study in rats and humans.

    Science.gov (United States)

    Skosnik, Patrick D; Hajós, Mihály; Cortes-Briones, Jose A; Edwards, Chad R; Pittman, Brian P; Hoffmann, William E; Sewell, Andrew R; D'Souza, Deepak C; Ranganathan, Mohini

    2018-06-01

    Cannabis use has been associated with altered sensory gating and neural oscillations. However, it is unclear which constituent in cannabis is responsible for these effects, or whether these are cannabinoid receptor 1 (CB1R) mediated. Therefore, the present study in humans and rats examined whether cannabinoid administration would disrupt sensory gating and evoked oscillations utilizing electroencephalography (EEG) and local field potentials (LFPs), respectively. Human subjects (n = 15) completed four test days during which they received intravenous delta-9-tetrahydrocannabinol (Δ 9 -THC), cannabidiol (CBD), Δ 9 -THC + CBD, or placebo. Subjects engaged in a dual-click paradigm, and outcome measures included P50 gating ratio (S2/S1) and evoked power to S1 and S2. In order to examine CB1R specificity, rats (n = 6) were administered the CB1R agonist CP-55940, CP-55940+AM-251 (a CB1R antagonist), or vehicle using the same paradigm. LFPs were recorded from CA3 and entorhinal cortex. Both Δ 9 -THC (p < 0.007) and Δ 9 -THC + CBD (p < 0.004) disrupted P50 gating ratio compared to placebo, while CBD alone had no effect. Δ 9 -THC (p < 0.048) and Δ 9 -THC + CBD (p < 0.035) decreased S1 evoked theta power, and in the Δ 9 -THC condition, S1 theta negatively correlated with gating ratios (r = -0.629, p < 0.012 (p < 0.048 adjusted)). In rats, CP-55940 disrupted gating in both brain regions (p < 0.0001), and this was reversed by AM-251. Further, CP-55940 decreased evoked theta (p < 0.0077) and gamma (p < 0.011) power to S1, which was partially blocked by AM-251. These convergent human/animal data suggest that CB1R agonists disrupt sensory gating by altering neural oscillations in the theta-band. Moreover, this suggests that the endocannabinoid system mediates theta oscillations relevant to perception and cognition. Copyright © 2018 Elsevier Ltd. All rights reserved.

  6. Consequence of dopamine D2 receptor blockade on the hyperphagic effect induced by cannabinoid CB1 and CB2 receptors in layers.

    Science.gov (United States)

    Khodadadi, M; Zendehdel, M; Baghbanzadeh, A; Babapour, V

    2017-10-01

    1. Endocannabinoids (ECBs) and their receptors play a regulatory function on several physiological processes such as feed-intake behaviour, mainly in the brain. This study was carried out in order to investigate the effects of the dopaminergic D1 and D2 receptors on CB1/CB2 ECB receptor-induced hyperphagia in 3-h feed-deprived neonatal layer chickens. 2. A total of 8 experiments were designed to explore the interplay of these two modulatory systems on feed intake in neonatal chickens. In Experiment 1, chickens were intracerebroventricular (ICV) injected with control solution, l-DOPA (levo-dihydroxyphenylalanine as precursor of dopamine; 125 nmol), 2-AG (2-arachidonoylglycerol as CB 1 receptor agonist; 2 µg) and co-administration of l-DOPA (125 nmol) plus 2-AG (2 µg). Experiments 2-4 were similar to Experiment 1 except birds were injected with either 6-OHDA (6-hydroxydopamine as dopamine synthesis inhibitor; 150 nmol), SCH23390 (D1 receptor antagonist; 5 nmol) and AMI-193 (D2 receptor antagonist; 5 nmol) instead of l-DOPA, respectively. Additionally, Experiments 5-8 followed the previous ones using the same dose of l-DOPA, 6-OHDA and dopamine antagonists except that birds were injected with CB65 (CB2 receptor agonist; 5 µg) instead of 2-AG. Coadministrations were at the same dose for each experiment. Cumulative feed intakes were measured until 120 min after each injection. 3. ICV administration of 6-OHDA and AMI-193 significantly attenuated 2-AG-induced hyperphagia. Interestingly, the hyperphagic effect of CB65 was significantly attenuated by administration of l-DOPA, whereas the administration of 6-OHDA and AMI-193 together amplified the hyperphagic effect of CB65. 4. It was concluded that cannabinoid-induced feeding behaviour is probably modulated by dopamine receptors in neonatal layer-type chickens. It seems that their interaction may be mediated by the D2-dopamine receptor.

  7. In vivo type 2 cannabinoid receptor-targeted tumor optical imaging using a near infrared fluorescent probe.

    Science.gov (United States)

    Zhang, Shaojuan; Shao, Pin; Bai, Mingfeng

    2013-11-20

    The type 2 cannabinoid receptor (CB2R) plays a vital role in carcinogenesis and progression and is emerging as a therapeutic target for cancers. However, the exact role of CB2R in cancer progression and therapy remains unclear. This has driven the increasing efforts to study CB2R and cancers using molecular imaging tools. In addition, many types of cancers overexpress CB2R, and the expression levels of CB2R appear to be associated with tumor aggressiveness. Such upregulation of the receptor in cancer cells provides opportunities for CB2R-targeted imaging with high contrast and for therapy with low side effects. In the present study, we report the first in vivo tumor-targeted optical imaging using a novel CB2R-targeted near-infrared probe. In vitro cell fluorescent imaging and a competitive binding assay indicated specific binding of NIR760-mbc94 to CB2R in CB2-mid delayed brain tumor (DBT) cells. NIR760-mbc94 also preferentially labeled CB2-mid DBT tumors in vivo, with a 3.7-fold tumor-to-normal contrast enhancement at 72 h postinjection, whereas the fluorescence signal from the tumors of the mice treated with NIR760 free dye was nearly at the background level at the same time point. SR144528, a CB2R competitor, significantly inhibited tumor uptake of NIR760-mbc94, indicating that NIR760-mbc94 binds to CB2R specifically. In summary, NIR760-mbc94 specifically binds to CB2R in vitro and in vivo and appears to be a promising molecular tool that may have great potential for use in diagnostic imaging of CB2R-positive cancers and therapeutic monitoring as well as in elucidating the role of CB2R in cancer progression and therapy.

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

    International Nuclear Information System (INIS)

    Kronfeld, Andrea; Müller-Forell, Wibke; Buchholz, Hans-Georg; Maus, Stephan; Reuss, Stefan; Schreckenberger, Mathias; Miederer, Isabelle; Lutz, Beat

    2015-01-01

    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 [ 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 templates

  9. 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.

  10. 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

  11. Plant-derived cannabinoids modulate the activity of transient receptor potential channels of ankyrin type-1 and melastatin type-8.

    Science.gov (United States)

    De Petrocellis, Luciano; Vellani, Vittorio; Schiano-Moriello, Aniello; Marini, Pietro; Magherini, Pier Cosimo; Orlando, Pierangelo; Di Marzo, Vincenzo

    2008-06-01

    The plant cannabinoids (phytocannabinoids), cannabidiol (CBD), and Delta(9)-tetrahydrocannabinol (THC) were previously shown to activate transient receptor potential channels of both vanilloid type 1 (TRPV1) and ankyrin type 1 (TRPA1), respectively. Furthermore, the endocannabinoid anandamide is known to activate TRPV1 and was recently found to antagonize the menthol- and icilin-sensitive transient receptor potential channels of melastatin type 8 (TRPM8). In this study, we investigated the effects of six phytocannabinoids [i.e., CBD, THC, CBD acid, THC acid, cannabichromene (CBC), and cannabigerol (CBG)] on TRPA1- and TRPM8-mediated increase in intracellular Ca2+ in either HEK-293 cells overexpressing the two channels or rat dorsal root ganglia (DRG) sensory neurons. All of the compounds tested induced TRPA1-mediated Ca2+ elevation in HEK-293 cells with efficacy comparable with that of mustard oil isothiocyanates (MO), the most potent being CBC (EC(50) = 60 nM) and the least potent being CBG and CBD acid (EC(50) = 3.4-12.0 microM). CBC also activated MO-sensitive DRG neurons, although with lower potency (EC(50) = 34.3 microM). Furthermore, although none of the compounds tested activated TRPM8-mediated Ca2+ elevation in HEK-293 cells, they all, with the exception of CBC, antagonized this response when it was induced by either menthol or icilin. CBD, CBG, THC, and THC acid were equipotent (IC(50) = 70-160 nM), whereas CBD acid was the least potent compound (IC(50) = 0.9-1.6 microM). CBG inhibited Ca2+ elevation also in icilin-sensitive DRG neurons with potency (IC(50) = 4.5 microM) similar to that of anandamide (IC(50) = 10 microM). Our findings suggest that phytocannabinoids and cannabis extracts exert some of their pharmacological actions also by interacting with TRPA1 and TRPM8 channels, with potential implications for the treatment of pain and cancer.

  12. The central cannabinoid CB1 receptor is required for diet-induced obesity and rimonabant's antiobesity effects in mice.

    Science.gov (United States)

    Pang, Zhen; Wu, Nancy N; Zhao, Weiguang; Chain, David C; Schaffer, Erica; Zhang, Xin; Yamdagni, Preeti; Palejwala, Vaseem A; Fan, Chunpeng; Favara, Sarah G; Dressler, Holly M; Economides, Kyriakos D; Weinstock, Daniel; Cavallo, Jean S; Naimi, Souad; Galzin, Anne-Marie; Guillot, Etienne; Pruniaux, Marie-Pierre; Tocci, Michael J; Polites, H Greg

    2011-10-01

    Cannabinoid receptor CB1 is expressed abundantly in the brain and presumably in the peripheral tissues responsible for energy metabolism. It is unclear if the antiobesity effects of rimonabant, a CB1 antagonist, are mediated through the central or the peripheral CB1 receptors. To address this question, we generated transgenic mice with central nervous system (CNS)-specific knockdown (KD) of CB1, by expressing an artificial microRNA (AMIR) under the control of the neuronal Thy1.2 promoter. In the mutant mice, CB1 expression was reduced in the brain and spinal cord, whereas no change was observed in the superior cervical ganglia (SCG), sympathetic trunk, enteric nervous system, and pancreatic ganglia. In contrast to the neuronal tissues, CB1 was undetectable in the brown adipose tissue (BAT) or the liver. Consistent with the selective loss of central CB1, agonist-induced hypothermia was attenuated in the mutant mice, but the agonist-induced delay of gastrointestinal transit (GIT), a primarily peripheral nervous system-mediated effect, was not. Compared to wild-type (WT) littermates, the mutant mice displayed reduced body weight (BW), adiposity, and feeding efficiency, and when fed a high-fat diet (HFD), showed decreased plasma insulin, leptin, cholesterol, and triglyceride levels, and elevated adiponectin levels. Furthermore, the therapeutic effects of rimonabant on food intake (FI), BW, and serum parameters were markedly reduced and correlated with the degree of CB1 KD. Thus, KD of CB1 in the CNS recapitulates the metabolic phenotype of CB1 knockout (KO) mice and diminishes rimonabant's efficacy, indicating that blockade of central CB1 is required for rimonabant's antiobesity actions.

  13. 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.

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

    International Nuclear Information System (INIS)

    Vandeputte, Caroline; Casteels, Cindy; Koole, Michel; Gerits, Anneleen; Struys, Tom; Veghel, Daisy van; Evens, Nele; Bormans, Guy; Dresselaers, Tom; Himmelreich, Uwe; Lambrichts, Ivo; Laere, Koen van

    2012-01-01

    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 1 and CB 2 ) have been suggested. The purpose of this study was to evaluate CB 1 and CB 2 receptor binding over time in vivo in a rat photothrombotic stroke model using PET. CB 1 and CB 2 microPET imaging was performed at regular time-points up to 2 weeks after stroke using [ 18 F]MK-9470 and [ 11 C]NE40. Stroke size was measured using MRI at 9.4 T. Ex vivo validation was performed via immunostaining for CB 1 and CB 2 . Immunofluorescent double stainings were also performed with markers for astrocytes (GFAP) and macrophages/microglia (CD68). [ 18 F]MK-9470 PET showed a strong increase in CB 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 1 immunohistochemical staining. [ 11 C]NE40 did not show any significant differences between stroke and sham-operated animals, although staining for CB 2 revealed minor immunoreactivity at 1 and 2 weeks after stroke in this model. Both CB 1 + and CB 2 + cells showed minor immunoreactivity for CD68. Time-dependent and regionally strongly increased CB 1 , but not CB 2 , binding are early consequences of photothrombotic stroke. Pharmacological interventions should primarily aim at CB 1 signalling as the role of CB 2 seems minor in the acute and subacute phases of stroke. (orig.)

  15. 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.)

  16. A Review of the Therapeutic Antitumor Potential of Cannabinoids.

    Science.gov (United States)

    Bogdanović, Višnja; Mrdjanović, Jasminka; Borišev, Ivana

    2017-11-01

    The aim of this review is to discuss cannabinoids from a preclinical and clinical oncological perspective and provide the audience with a concise, retrospective overview of the most significant findings concerning the potential use of cannabinoids in cancer treatment. A literature survey of medical and scientific databases was conducted with a focus on the biological and medical potential of cannabinoids in cancer treatment. Cannabis sativa is a plant rich in more than 100 types of cannabinoids. Besides exogenous plant cannabinoids, mammalian endocannabinoids and synthetic cannabinoid analogues have been identified. Cannabinoid receptors type 1 (CB1) and type 2 (CB2) have been isolated and characterized from mammalian cells. Through cannabinoid receptor and non-receptor signaling pathways, cannabinoids show specific cytotoxicity against tumor cells, while protecting healthy tissue from apoptosis. The dual antiproliferative and proapoptotic effects of cannabinoids and associated signaling pathways have been investigated on a large panel of cancer cell lines. Cannabinoids also display potent anticancer activity against tumor xenografts, including tumors that express high resistance to standard chemotherapeutics. Few studies have investigated the possible synergistic effects of cannabinoids with standard oncology therapies, and are based on the preclinically confirmed concept of "cannabinoid sensitizers." Also, clinical trials aimed to confirm the antineoplastic activity of cannabinoids have only been evaluated on a small number of subjects, with no consensus conclusions regarding their effectiveness. A large number of cannabinoid compounds have been discovered, developed, and used to study the effects of cannabinoids on cancers in model systems. However, few clinical trials have been conducted on the use of cannabinoids in the treatment of cancers in humans. Further studies require extensive monitoring of the effects of cannabinoids alone or in combination with

  17. Modulation of cannabinoid receptor activation as a neuroprotective strategy for EAE and stroke.

    Science.gov (United States)

    Zhang, Ming; Martin, Billy R; Adler, Martin W; Razdan, Raj J; Kong, Weimin; Ganea, Doina; Tuma, Ronald F

    2009-06-01

    Recognition of the importance of the endocannabinoid system in both homeostasis and pathologic responses raised interest recently in the development of therapeutic agents based on this system. The CB(2) receptor, a component of the endocannabinoid system, has significant influence on immune function and inflammatory responses. Inflammatory responses are major contributors to central nervous system (CNS) injury in a variety of diseases. In this report, we present evidence that activation of CB(2) receptors, by selective CB(2) agonists, reduces inflammatory responses that contribute to CNS injury. The studies demonstrate neuroprotective effects in experimental autoimmune encephalomyelitis, a model of multiple sclerosis, and in a murine model of cerebral ischemia/reperfusion injury. In both cases, CB(2) receptor activation results in reduced white cell rolling and adhesion to cerebral microvessels, a reduction in immune cell invasion, and improved neurologic function after insult. In addition, administration of the CB(1) antagonist SR141716A reduces infarct size following ischemia/reperfusion injury. Administration of both a selective CB(2) agonist and a CB(1) antagonist has the unique property of increasing blood flow to the brain during the occlusion period, suggesting an effect on collateral blood flow. In summary, selective CB(2) receptor agonists and CB(1) receptor antagonists have significant potential for neuroprotection in animal models of two devastating diseases that currently lack effective treatment options.

  18. Consequences of Adolescent Exposure to the Cannabinoid Receptor Agonist WIN55,212-2 on Working Memory in Female Rats

    OpenAIRE

    Erin K. Kirschmann; Daniel M. McCalley; Caitlyn M. Edwards; Caitlyn M. Edwards; Mary M. Torregrossa; Mary M. Torregrossa

    2017-01-01

    Marijuana is a prevalent illicit substance used by adolescents, and several studies have indicated that adolescent use can lead to long-term cognitive deficits including problems with attention and memory. However, preclinical animal studies that observe cognitive deficits after cannabinoid exposure during adolescence utilize experimenter administration of doses of cannabinoids that may exceed what an organism would choose to take, suggesting that contingency and dose are critical factors tha...

  19. Pharmacokinetic-pharmacodynamic analysis of antipsychotics-induced extrapyramidal symptoms based on receptor occupancy theory incorporating endogenous dopamine release.

    Science.gov (United States)

    Matsui-Sakata, Akiko; Ohtani, Hisakazu; Sawada, Yasufumi

    2005-06-01

    We aimed to analyze the risks of extrapyramidal symptoms (EPS) induced by typical and atypical antipsychotic drugs using a common pharmacokinetic-pharmacodynamic (PK-PD) model based on the receptor occupancy. We collected the data for EPS induced by atypical antipsychotics, risperidone, olanzapine and quetiapine, and a typical antipsychotic, haloperidol from literature and analyzed the following five indices of EPS, the ratio of patients obliged to take anticholinergic medication, the occurrence rates of plural extrapyramidal symptoms (more than one of tremor, dystonia, hypokinesia, akathisia, extrapyramidal syndrome, etc.), parkinsonism, akathisia, and extrapyramidal syndrome. We tested two models, i.e., a model incorporating endogenous dopamine release owing to 5-HT2A receptor inhibition and a model not considering the endogenous dopamine release, and used them to examine the relationship between the D2 receptor occupancy of endogenous dopamine and the extent of drug-induced EPS. The model incorporating endogenous dopamine release better described the relationship between the mean D2 receptor occupancy of endogenous dopamine and the extent of EPS than the other model, as assessed by the final sum of squares of residuals (final SS) and Akaike's Information Criteria (AIC). Furthermore, the former model could appropriately predict the risks of EPS induced by two other atypical antipsychotics, clozapine and ziprasidone, which were not incorporated into the model development. The developed model incorporating endogenous dopamine release owing to 5-HT2A receptor inhibition may be useful for the prediction of antipsychotics-induced EPS.

  20. Stimulation of brain glucose uptake by cannabinoid CB2 receptors and its therapeutic potential in Alzheimer's disease.

    Science.gov (United States)

    Köfalvi, Attila; Lemos, Cristina; Martín-Moreno, Ana M; Pinheiro, Bárbara S; García-García, Luis; Pozo, Miguel A; Valério-Fernandes, Ângela; Beleza, Rui O; Agostinho, Paula; Rodrigues, Ricardo J; Pasquaré, Susana J; Cunha, Rodrigo A; de Ceballos, María L

    2016-11-01

    Cannabinoid CB2 receptors (CB2Rs) are emerging as important therapeutic targets in brain disorders that typically involve neurometabolic alterations. We here addressed the possible role of CB2Rs in the regulation of glucose uptake in the mouse brain. To that aim, we have undertaken 1) measurement of (3)H-deoxyglucose uptake in cultured cortical astrocytes and neurons and in acute hippocampal slices; 2) real-time visualization of fluorescently labeled deoxyglucose uptake in superfused hippocampal slices; and 3) in vivo PET imaging of cerebral (18)F-fluorodeoxyglucose uptake. We now show that both selective (JWH133 and GP1a) as well as non-selective (WIN55212-2) CB2R agonists, but not the CB1R-selective agonist, ACEA, stimulate glucose uptake, in a manner that is sensitive to the CB2R-selective antagonist, AM630. Glucose uptake is stimulated in astrocytes and neurons in culture, in acute hippocampal slices, in different brain areas of young adult male C57Bl/6j and CD-1 mice, as well as in middle-aged C57Bl/6j mice. Among the endocannabinoid metabolizing enzymes, the selective inhibition of COX-2, rather than that of FAAH, MAGL or α,βDH6/12, also stimulates the uptake of glucose in hippocampal slices of middle-aged mice, an effect that was again prevented by AM630. However, we found the levels of the endocannabinoid, anandamide reduced in the hippocampus of TgAPP-2576 mice (a model of β-amyloidosis), and likely as a consequence, COX-2 inhibition failed to stimulate glucose uptake in these mice. Together, these results reveal a novel general glucoregulatory role for CB2Rs in the brain, raising therapeutic interest in CB2R agonists as nootropic agents. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

  1. CB2 cannabinoid receptors modulate HIF-1α and TIM-3 expression in a hypoxia-ischemia mouse model.

    Science.gov (United States)

    Kossatz, Elk; Maldonado, Rafael; Robledo, Patricia

    2016-12-01

    The role of CB2 cannabinoid receptors (CB 2 R) in global brain lesions induced by hypoxia-ischemia (HI) insult is still unresolved. The aim of this study was to evaluate the involvement of CB 2 R in the behavioural and biochemical underpinnings related to brain damage induced by HI in adult mice, and the mechanisms involved. CB 2 R knockout (KO) mice and wild-type littermates (WT) underwent permanent ligation of the left common carotid artery and hypoxia. Behavioural measurements in the rotarod, beam walking, object recognition, open field, and Irwin tests were carried out 24h, 72h and 7 days. In KO mice, more extensive brain injury was observed. Behavioural deficits in the Irwin test were observed in both genotypes; while WT mice showed progressive recovery by day 7, KO mice did not. Only KO mice showed alterations in motor learning, coordination and balance, and did not recover over time. A higher expression of microglia and astrocytes was observed in several brain areas of lesioned WT and KO mice. The possible alteration of the inflammatory-related factors HIF-1α and TIM-3 was evaluated in these animals. In both genotypes, HIF-1α and TIM-3 expression was observed in lesioned areas associated with activated microglia. However, the expression levels of these proteins were exacerbated in KO mice in several lesioned and non-lesioned brain structures. Our results indicate that CB 2 R may have a crucial neuroprotective role following HI insult through the modulation of the inflammatory-related HIF-1α/TIM-3 signalling pathway in microglia. Copyright © 2016 Elsevier B.V. and ECNP. All rights reserved.

  2. Kinetic analysis of the cannabinoid-1 receptor PET tracer [18F]MK-9470 in human brain

    International Nuclear Information System (INIS)

    Sanabria-Bohorquez, Sandra Marina; Hamill, Terence G.; Burns, H.D.; Goffin, Karolien; Laere, Koen van; Lepeleire, Inge de; Bormans, Guy

    2010-01-01

    Quantitative imaging of the type 1 cannabinoid receptor (CB1R) opens perspectives for many neurological and psychiatric disorders. We characterized the kinetics and reproducibility of the CB1R tracer [ 18 F]MK-9470 in human brain. [ 18 F]MK-9470 data were analysed using reversible models and the distribution volume V T and V ND k 3 (V ND k 3 = K 1 k 2 ) were estimated. Tracer binding was also evaluated using irreversible kinetics and the irreversible uptake constant K i and fractional uptake rate (FUR) were estimated. The effect of blood flow on these parameters was evaluated. Additionally, the possibility of determining the tracer plasma kinetics using a reduced number of blood samples was also examined. A reversible two-tissue compartment model using a global k 4 value was necessary to describe brain kinetics. Both V T and V ND k 3 were estimated satisfactorily and their test-retest variability was between 10% and 30%. Irreversible methods adequately described brain kinetics and FUR values were equivalent to K i . The linear relationship between K i and V ND k 3 demonstrated that K i or FUR and thus the simple measure of tracer brain uptake provide CB1R availability information. The test-retest variability of K i and FUR was 18 F]MK-9470 specific binding can be accurately determined using FUR values requiring a short scan 90 to 120 min after tracer administration. Our results suggest that [ 18 F]MK-9470 plasma kinetics can be assessed using a few venous samples. (orig.)

  3. Cannabinoid Receptors Mediate Methamphetamine Induction of High Frequency Gamma Oscillations in the Nucleus Accumbens

    Science.gov (United States)

    Morra, Joshua T.; Glick, Stanley D.; Cheer, Joseph F.

    2012-01-01

    Patients suffering from amphetamine---induced psychosis display repetitive behaviors, partially alleviated by antipsychotics, which are reminiscent of rodent stereotypies. Due to recent evidence implicating endocannabinoid involvement in brain disorders, including psychosis, we studied the effects of endocannabinoid signaling on neuronal oscillations of rats exhibiting methamphetamine stereotypy. Neuronal network oscillations were recorded with multiple single electrode arrays aimed at the nucleus accumbens of freely moving rats. During the experiments, animals were dosed intravenously with the CB1 receptor antagonist rimonabant (0.3 mg/kg) or vehicle followed by an ascending dose regimen of methamphetamine (0.01, 0.1, 1, and 3 mg/kg; cumulative dosing). The effects of drug administration on stereotypy and local gamma oscillations were evaluated. Methamphetamine treatment significantly increased high frequency gamma oscillations (~ 80 Hz). Entrainment of a subpopulation of nucleus accumbens neurons to high frequency gamma was associated with stereotypy encoding in putative fast-spiking interneurons, but not in putative medium spiny neurons. The observed ability of methamphetamine to induce both stereotypy and high frequency gamma power was potently disrupted following CB1 receptor blockade. The present data suggest that CB1 receptor-dependent mechanisms are recruited by methamphetamine to modify striatal interneuron oscillations that accompany changes in psychomotor state, further supporting the link between endocannabinoids and schizophrenia spectrum disorders. PMID:22609048

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

    International Nuclear Information System (INIS)

    Singh, Udai P.; Singh, Narendra P.; Singh, Balwan; Price, Robert L.; Nagarkatti, Mitzi; Nagarkatti, Prakash S.

    2012-01-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2012-01-15

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

  6. Crystal structures of a GABAA-receptor chimera reveal new endogenous neurosteroid-binding sites.

    Science.gov (United States)

    Laverty, Duncan; Thomas, Philip; Field, Martin; Andersen, Ole J; Gold, Matthew G; Biggin, Philip C; Gielen, Marc; Smart, Trevor G

    2017-11-01

    γ-Aminobutyric acid receptors (GABA A Rs) are vital for controlling excitability in the brain. This is emphasized by the numerous neuropsychiatric disorders that result from receptor dysfunction. A critical component of most native GABA A Rs is the α subunit. Its transmembrane domain is the target for many modulators, including endogenous brain neurosteroids that impact anxiety, stress and depression, and for therapeutic drugs, such as general anesthetics. Understanding the basis for the modulation of GABA A R function requires high-resolution structures. Here we present the first atomic structures of a GABA A R chimera at 2.8-Å resolution, including those bound with potentiating and inhibitory neurosteroids. These structures define new allosteric binding sites for these modulators that are associated with the α-subunit transmembrane domain. Our findings will enable the exploitation of neurosteroids for therapeutic drug design to regulate GABA A Rs in neurological disorders.

  7. Intracellular postsynaptic cannabinoid receptors link thyrotropin-releasing hormone receptors to TRPC-like channels in thalamic paraventricular nucleus neurons.

    Science.gov (United States)

    Zhang, L; Kolaj, M; Renaud, L P

    2015-12-17

    In rat thalamic paraventricular nucleus of thalamus (PVT) neurons, activation of thyrotropin-releasing hormone (TRH) receptors enhances excitability via concurrent decrease in G protein-coupled inwardly-rectifying potassium (GIRK)-like and activation of transient receptor potential cation (TRPC)4/5-like cationic conductances. An exploration of intracellular signaling pathways revealed the TRH-induced current to be insensitive to phosphatidylinositol-specific phospholipase C (PI-PLC) inhibitors, but reduced by D609, an inhibitor of phosphatidylcholine-specific PLC (PC-PLC). A corresponding change in the I-V relationship implied suppression of the cationic component of the TRH-induced current. Diacylglycerol (DAG) is a product of the hydrolysis of PC. Studies focused on the isolated cationic component of the TRH-induced response revealed a reduction by RHC80267, an inhibitor of DAG lipase, the enzyme involved in the hydrolysis of DAG to the endocannabinoid 2-arachidonoylglycerol (2-AG). Further investigation revealed enhancement of the cationic component in the presence of either JZL184 or WWL70, inhibitors of enzymes involved in the hydrolysis of 2-AG. A decrease in the TRH-induced response was noted in the presence of rimonabant or SR144528, membrane permeable CB1 and CB2 receptor antagonists, respectively. A decrease in the TRH-induced current by intracellular, but not by bath application of the membrane impermeable peptide hemopressin, selective for CB1 receptors, suggests a postsynaptic intracellular localization of these receptors. The TRH-induced current was increased in the presence of arachidonyl-2'-chloroethylamide (ACEA) or JWH133, CB1 and CB2 receptor agonists, respectively. The PI3-kinase inhibitor LY294002, known to inhibit TRPC translocation, decreased the response to TRH. In addition, a TRH-induced enhancement of the low-threshold spike was prevented by both rimonabant, and SR144528. TRH had no influence on excitatory or inhibitory miniature

  8. A key agonist-induced conformational change in the cannabinoid receptor CB1 is blocked by the allosteric ligand Org 27569.

    Science.gov (United States)

    Fay, Jonathan F; Farrens, David L

    2012-09-28

    Allosteric ligands that modulate how G protein-coupled receptors respond to traditional orthosteric drugs are an exciting and rapidly expanding field of pharmacology. An allosteric ligand for the cannabinoid receptor CB1, Org 27569, exhibits an intriguing effect; it increases agonist binding, yet blocks agonist-induced CB1 signaling. Here we explored the mechanism behind this behavior, using a site-directed fluorescence labeling approach. Our results show that Org 27569 blocks conformational changes in CB1 that accompany G protein binding and/or activation, and thus inhibit formation of a fully active CB1 structure. The underlying mechanism behind this behavior is that simultaneous binding of Org 27569 produces a unique agonist-bound conformation, one that may resemble an intermediate structure formed on the pathway to full receptor activation.

  9. The effect of leptin receptor deficiency and fasting on cannabinoid receptor 1 mRNA expression in the rat hypothalamus, brainstem and nodose ganglion.

    Science.gov (United States)

    Jelsing, Jacob; Larsen, Philip Just; Vrang, Niels

    2009-10-02

    Despite ample evidence for the involvement of the endocannabinoid system in the control of appetite, food intake and energy balance, relatively little is known about the regulation of cannabinoid receptor 1 (CB(1)R) expression in respect to leptin signalling and fasting. In the present study, we examined CB(1)R mRNA levels in lean (Fa/?) and obese (fa/fa) male Zucker rats under basal and food-restricted conditions. Using stereological sampling principles coupled with semi-quantitative radioactive in situ hybridization we provide semi-quantitative estimates of CB(1)R mRNA expression in key appetite regulatory hypothalamic and brainstem areas, as well as in the nodose ganglia. Whereas no effect of fasting were determined on CB(1)R mRNA levels in the paraventricular (PVN) and ventromedial hypothalamic (VMH) nucleus, in the brainstem dorsal vagal complex or nodose ganglion of lean Zucker rats, CB(1)R mRNA levels were consistently elevated in obese Zucker rats pointing to a direct influence of disrupted leptin signalling on CB(1)R mRNA regulation.

  10. Kinetic analysis of the cannabinoid-1 receptor PET tracer [{sup 18}F]MK-9470 in human brain

    Energy Technology Data Exchange (ETDEWEB)

    Sanabria-Bohorquez, Sandra Marina; Hamill, Terence G.; Burns, H.D. [Merck Research Laboratories, Imaging, West Point, PA (United States); Goffin, Karolien; Laere, Koen van [University Hospital and K.U. Leuven, Division of Nuclear Medicine, Leuven (Belgium); Lepeleire, Inge de [Merck Research Laboratories, Brussels (Belgium); Bormans, Guy [K.U. Leuven, Laboratory of Radiopharmacy, Leuven (Belgium)

    2010-05-15

    Quantitative imaging of the type 1 cannabinoid receptor (CB1R) opens perspectives for many neurological and psychiatric disorders. We characterized the kinetics and reproducibility of the CB1R tracer [{sup 18}F]MK-9470 in human brain. [{sup 18}F]MK-9470 data were analysed using reversible models and the distribution volume V{sub T} and V{sub ND} k{sub 3} (V{sub ND} k{sub 3} = K{sub 1} k{sub 2}) were estimated. Tracer binding was also evaluated using irreversible kinetics and the irreversible uptake constant K{sub i} and fractional uptake rate (FUR) were estimated. The effect of blood flow on these parameters was evaluated. Additionally, the possibility of determining the tracer plasma kinetics using a reduced number of blood samples was also examined. A reversible two-tissue compartment model using a global k{sub 4} value was necessary to describe brain kinetics. Both V{sub T} and V{sub ND} k{sub 3} were estimated satisfactorily and their test-retest variability was between 10% and 30%. Irreversible methods adequately described brain kinetics and FUR values were equivalent to K{sub i}. The linear relationship between K{sub i} and V{sub ND} k{sub 3} demonstrated that K{sub i} or FUR and thus the simple measure of tracer brain uptake provide CB1R availability information. The test-retest variability of K{sub i} and FUR was <10% and estimates were independent of blood flow. Brain uptake can be used as a receptor availability index, albeit at the expense of potential bias due to between-subject differences in tracer plasma kinetics. [{sup 18}F]MK-9470 specific binding can be accurately determined using FUR values requiring a short scan 90 to 120 min after tracer administration. Our results suggest that [{sup 18}F]MK-9470 plasma kinetics can be assessed using a few venous samples. (orig.)

  11. Marijuana and cannabinoid regulation of brain reward circuits.

    Science.gov (United States)

    Lupica, Carl R; Riegel, Arthur C; Hoffman, Alexander F

    2004-09-01

    The reward circuitry of the brain consists of neurons that synaptically connect a wide variety of nuclei. Of these brain regions, the ventral tegmental area (VTA) and the nucleus accumbens (NAc) play central roles in the processing of rewarding environmental stimuli and in drug addiction. The psychoactive properties of marijuana are mediated by the active constituent, Delta(9)-THC, interacting primarily with CB1 cannabinoid receptors in a large number of brain areas. However, it is the activation of these receptors located within the central brain reward circuits that is thought to play an important role in sustaining the self-administration of marijuana in humans, and in mediating the anxiolytic and pleasurable effects of the drug. Here we describe the cellular circuitry of the VTA and the NAc, define the sites within these areas at which cannabinoids alter synaptic processes, and discuss the relevance of these actions to the regulation of reinforcement and reward. In addition, we compare the effects of Delta(9)-THC with those of other commonly abused drugs on these reward circuits, and we discuss the roles that endogenous cannabinoids may play within these brain pathways, and their possible involvement in regulating ongoing brain function, independently of marijuana consumption. We conclude that, whereas Delta(9)-THC alters the activity of these central reward pathways in a manner that is consistent with other abused drugs, the cellular mechanism through which this occurs is likely different, relying upon the combined regulation of several afferent pathways to the VTA.

  12. Cannabinoid transmission in the prelimbic cortex bidirectionally controls opiate reward and aversion signaling through dissociable kappa versus μ-opiate receptor dependent mechanisms.

    Science.gov (United States)

    Ahmad, Tasha; Lauzon, Nicole M; de Jaeger, Xavier; Laviolette, Steven R

    2013-09-25

    Cannabinoid, dopamine (DA), and opiate receptor pathways play integrative roles in emotional learning, associative memory, and sensory perception. Modulation of cannabinoid CB1 receptor transmission within the medial prefrontal cortex (mPFC) regulates the emotional valence of both rewarding and aversive experiences. Furthermore, CB1 receptor substrates functionally interact with opiate-related motivational processing circuits, particularly in the context of reward-related learning and memory. Considerable evidence demonstrates functional interactions between CB1 and DA signaling pathways during the processing of motivationally salient information. However, the role of mPFC CB1 receptor transmission in the modulation of behavioral opiate-reward processing is not currently known. Using an unbiased conditioned place preference paradigm with rats, we examined the role of intra-mPFC CB1 transmission during opiate reward learning. We report that activation or inhibition of CB1 transmission within the prelimbic cortical (PLC) division of the mPFC bidirectionally regulates the motivational valence of opiates; whereas CB1 activation switched morphine reward signaling into an aversive stimulus, blockade of CB1 transmission potentiated the rewarding properties of normally sub-reward threshold conditioning doses of morphine. Both of these effects were dependent upon DA transmission as systemic blockade of DAergic transmission prevented CB1-dependent modulation of morphine reward and aversion behaviors. We further report that CB1-mediated intra-PLC opiate motivational signaling is mediated through a μ-opiate receptor-dependent reward pathway, or a κ-opiate receptor-dependent aversion pathway, directly within the ventral tegmental area. Our results provide evidence for a novel CB1-mediated motivational valence switching mechanism within the PLC, controlling dissociable subcortical reward and aversion pathways.

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

    Science.gov (United States)

    Viñals, Xavier; Moreno, Estefanía; Lanfumey, Laurence; Cordomí, Arnau; Pastor, Antoni; de La Torre, Rafael; Gasperini, Paola; Navarro, Gemma; Howell, Lesley A; Pardo, Leonardo; Lluís, Carmen; Canela, Enric I; McCormick, Peter J; Maldonado, Rafael; Robledo, Patricia

    2015-07-01

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

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

    Directory of Open Access Journals (Sweden)

    Xavier Viñals

    2015-07-01

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

  15. The cannabinoid receptor 2 agonist, β-caryophyllene, reduced voluntary alcohol intake and attenuated ethanol-induced place preference and sensitivity in mice.

    Science.gov (United States)

    Al Mansouri, Shamma; Ojha, Shreesh; Al Maamari, Elyazia; Al Ameri, Mouza; Nurulain, Syed M; Bahi, Amine

    2014-09-01

    Several recent studies have suggested that brain CB2 cannabinoid receptors play a major role in alcohol reward. In fact, the implication of cannabinoid neurotransmission in the reinforcing effects of ethanol (EtOH) is becoming increasingly evident. The CB2 receptor agonist, β-caryophyllene (BCP) was used to investigate the role of the CB2 receptors in mediating alcohol intake and ethanol-induced conditioned place preference (EtOH-CPP) and sensitivity in mice. The effect of BCP on alcohol intake was evaluated using the standard two-bottle choice drinking method. The mice were presented with increasing EtOH concentrations and its consumption was measured daily. Consumption of saccharin and quinine solutions was measured following the EtOH preference tests. Finally, the effect of BCP on alcohol reward and sensitivity was tested using an unbiased EtOH-CPP and loss of righting-reflex (LORR) procedures, respectively. BCP dose-dependently decreased alcohol consumption and preference. Additionally, BCP-injected mice did not show any difference from vehicle mice in total fluid intake in a 24-hour paradigm nor in their intake of graded concentrations of saccharin or quinine, suggesting that the CB2 receptor activation did not alter taste function. More importantly, BCP inhibited EtOH-CPP acquisition and exacerbated LORR duration. Interestingly, these effects were abrogated when mice were pre-injected with a selective CB2 receptor antagonist, AM630. Overall, the CB2 receptor system appears to be involved in alcohol dependence and sensitivity and may represent a potential pharmacological target for the treatment of alcoholism. Copyright © 2014 Elsevier Inc. All rights reserved.

  16. Suppressing effect of COR659 on alcohol, sucrose, and chocolate self-administration in rats: involvement of the GABAB and cannabinoid CB1 receptors.

    Science.gov (United States)

    Maccioni, Paola; Colombo, Giancarlo; Lorrai, Irene; Zaru, Alessandro; Carai, Mauro A M; Gessa, Gian Luigi; Brizzi, Antonella; Mugnaini, Claudia; Corelli, Federico

    2017-09-01

    COR659 [methyl2-(4-chlorophenylcarboxamido)-4-ethyl-5-methylthiophene-3-carboxylate] is a new, positive allosteric modulator (PAM) of the GABA B receptor. This study evaluated whether COR659 shared with previously tested GABA B PAMs the capacity to reduce alcohol self-administration in rats. Treatment with non-sedative doses of COR659 (2.5, 5, and 10 mg/kg; i.p.) suppressed lever-responding for alcohol (15% v/v) in Sardinian alcohol-preferring (sP) rats under the fixed ratio (FR) 4 (FR4) and progressive ratio (PR) schedules of reinforcement; COR659 was more potent and effective than the reference GABA B PAM, GS39783. Treatment with COR659, but not GS39783, suppressed (a) lever-responding for a sucrose solution (1-3% w/v) in sP rats under the FR4 and PR schedules, (b) lever-responding for a chocolate solution [5% (w/v) Nesquik®] in Wistar rats under the FR10 and PR schedules, and (c) cue-induced reinstatement of chocolate seeking in Wistar rats. Treatment with COR659 was completely ineffective on lever-responding (FR10) for regular food pellets in food-deprived Wistar rats. Pretreatment with the GABA B receptor antagonist, SCH50911, partially blocked COR659-induced reduction of alcohol self-administration, being ineffective on reduction of chocolate self-administration. Pretreatment with the cannabinoid CB 1 receptor antagonist, AM4113, fully blocked COR659-induced reduction of chocolate self-administration, being ineffective on reduction of alcohol self-administration. COR659 might exert its behavioral effects via a composite mechanism: (i) positive allosteric modulation of the GABA B receptor, responsible for a large proportion of reduction of alcohol self-administration; (ii) an action at other receptor system(s), including the cannabinoid CB 1 receptor, through which COR659 affects seeking and consumption of highly palatable foods.

  17. Synthesis and biological evaluation of carbon-11- and fluorine-18-labeled 2-oxoquinoline derivatives for type 2 cannabinoid receptor positron emission tomography imaging

    International Nuclear Information System (INIS)

    Evens, Nele; Muccioli, Giulio G.; Houbrechts, Nele; Lambert, Didier M.; Verbruggen, Alfons M.; Van Laere, Koen; Bormans, Guy M.

    2009-01-01

    Introduction: The type 2 cannabinoid (CB 2 ) receptor is part of the endocannabinoid system and has been suggested as a mediator of several central and peripheral inflammatory processes. Imaging of the CB 2 receptor has been unsuccessful so far. We synthesized and evaluated a carbon-11- and a fluorine-18-labeled 2-oxoquinoline derivative as new PET tracers with high specificity and affinity for the CB 2 receptor. Methods: Two 2-oxoquinoline derivatives were synthesized and radiolabeled with either carbon-11 or fluorine-18. Their affinity and selectivity for the human CB 2 receptor were determined. Biological evaluation was done by biodistribution, radiometabolite and autoradiography studies in mice. Results: In vitro studies showed that both compounds are high affinity CB 2 -specific inverse agonists. Biodistribution study of the tracers in mice showed a high in vivo initial brain uptake and fast brain washout, in accordance with the low CB 2 receptor expression levels in normal brain. A persistently high in vivo binding to the spleen was observed, which was inhibited by pretreatment with two structurally unrelated CB 2 selective inverse agonists. In vitro autoradiography studies with the radioligands confirmed CB 2 -specific binding to the mouse spleen. Conclusion: We synthesized two novel CB 2 receptor PET tracers that show high affinity/selectivity for CB 2 receptors. Both tracers show favourable characteristics as radioligands for central and peripheral in vivo visualization of the CB 2 receptor and are promising candidates for primate and human CB 2 PET imaging.

  18. Syntheses of 7-Substituted α-Cyperone Derivatives for Selective Sigma-1 Receptor over Cannabinoid-1 Receptor Binding Affinities

    Energy Technology Data Exchange (ETDEWEB)

    Park, Juyoung; Shin, Younggyun; Yoon, Sunghwa [Ajou Univ., Suwon (Korea, Republic of); Kim, Keewon; Kwon, Youngbae [ChonBuk National Univ., Jeonju (Korea, Republic of)

    2013-11-15

    We have successfully synthesized seven α-cyperone derivatives and found that the presence of a hydrogen bond donor/acceptor groups at the C7 position of α-cyperone significantly affects specificity and potency of CB{sub 1} receptor binding affinity over sigma-1 receptor binding affinity. In particular, the presence of the amino moiety at the C7 position of α-cyperone is beneficial for binding to sigmia-1 receptor. The molecular mechanism of compound 8 involved in the high binding affinity to sigma-1 receptor is under investigation. We first synthesized α-cyperone 1 by following the previously reported synthetic routes.15-19 In brief, azeotropic imination of (+)-dihydrocarvone and (R)-(+)-1-phenylethylamine followed by alkylation with a slight excess of ethyl vinyl ketone (EVK) in THF at 40 .deg. C produced the Micheal adduct. The resulting adduct was hydrolyzed and then treated with sodium methoxide at room temperature to give an easily separable mixture of α-cyperone 1 and its side product. Flash chromatography resulted in pure α-cyperone 1 in a 30% yield from (+)-dihydrocarvone.

  19. Cannabinoid Regulation of Brain Reward Processing with an Emphasis on the Role of CB1 Receptors: A Step Back into the Future.

    Science.gov (United States)

    Panagis, George; Mackey, Brian; Vlachou, Styliani

    2014-01-01

    Over the last decades, the endocannabinoid system has been implicated in a large variety of functions, including a crucial modulation of brain-reward circuits and the regulation of motivational processes. Importantly, behavioral studies have shown that cannabinoid compounds activate brain reward mechanisms and circuits in a similar manner to other drugs of abuse, such as nicotine, alcohol, cocaine, and heroin, although the conditions under which cannabinoids exert their rewarding effects may be more limited. Furthermore, there is evidence on the involvement of the endocannabinoid system in the regulation of cue- and drug-induced relapsing phenomena in animal models. The aim of this review is to briefly present the available data obtained using diverse behavioral experimental approaches in experimental animals, namely, the intracranial self-stimulation paradigm, the self-administration procedure, the conditioned place preference procedure, and the reinstatement of drug-seeking behavior procedure, to provide a comprehensive picture of the current status of what is known about the endocannabinoid system mechanisms that underlie modification of brain-reward processes. Emphasis is placed on the effects of cannabinoid 1 (CB1) receptor agonists, antagonists, and endocannabinoid modulators. Further, the role of CB1 receptors in reward processes is investigated through presentation of respective genetic ablation studies in mice. The vast majority of studies in the existing literature suggest that the endocannabinoid system plays a major role in modulating motivation and reward processes. However, much remains to be done before we fully understand these interactions. Further research in the future will shed more light on these processes and, thus, could lead to the development of potential pharmacotherapies designed to treat reward-dysfunction-related disorders.

  20. Cannabinoid regulation of brain reward processing with an emphasis on the role of CB1 receptors: a step back into the future

    Directory of Open Access Journals (Sweden)

    George ePanagis

    2014-07-01

    Full Text Available Over the last decades the endocannabinoid system has been implicated in a large variety of functions, including a crucial modulation of brain reward circuits and the regulation of motivational processes. Importantly, behavioural studies have shown that cannabinoid compounds activate brain reward mechanisms and circuits in a similar manner to other drugs of abuse, such as nicotine, alcohol, cocaine and heroin, although the conditions under which cannabinoids exert their rewarding effects may be more limited. Furthermore, there is evidence on the involvement of the endocannabinoid system in the regulation of cue- and drug-induced relapsing phenomena in animal models. The aim of this review is to briefly present the available data obtained using diverse behavioural experimental approaches in experimental animals, namely, the intracranial self-stimulation paradigm, the self-administration procedure, the conditioned place preference procedure and the reinstatement of drug-seeking behaviour procedure, to provide a comprehensive picture of the current status of what is known about the endocannabinoid system mechanisms that underlie modification of brain reward processes. Emphasis is placed on the effects of cannabinoid 1 (CB1 receptor agonists, antagonists and endocannabinoid modulators. Further, the role of CB1 receptors in reward processes is investigated through presentation of respective genetic ablation studies in mice. The vast majority of studies in the existing literature suggests that the endocannabinoid system plays a major role in modulating motivation and reward processes. However, much remains to be done before we fully understand these interactions. Further research in the future will shed more light on these processes and, thus, could lead to the development of potential pharmacotherapies designed to treat reward-dysfunction related disorders.

  1. Anti-Inflammatory and Osteoprotective Effects of Cannabinoid-2 Receptor Agonist HU-308 in a Rat Model of Lipopolysaccharide-Induced Periodontitis.

    Science.gov (United States)

    Ossola, Cesar A; Surkin, Pablo N; Mohn, Claudia E; Elverdin, Juan C; Fernández-Solari, Javier

    2016-06-01

    Anti-inflammatory and immunologic properties of cannabinoids have been reported in several tissues. Expression of cannabinoid receptor Type 2 was reported in osteoblasts and osteoclasts, suggesting a key role in bone metabolism. The aim of this study is to assess the effect of treatment with cannabinoid-2 receptor agonist HU-308 in the oral health of rats subjected to lipopolysaccharide (LPS)-induced periodontitis. Twenty-four rats were distributed in four groups (six rats per group): 1) control rats; 2) sham rats; 3) rats submitted to experimental periodontitis (LPS); and 4) rats submitted to experimental periodontitis and treated with HU-308 (LPS+HU). In groups LPS and LPS+HU, periodontitis was induced by LPS (1 mg/mL) injected into the gingival tissue (GT) of maxillary and mandibular first molars and into the interdental space between the first and second molars, 3 days per week for 6 weeks. In group LPS+HU, HU-308 (500 ng/mL) was applied topically to the GT daily. Alveolar bone loss resulting from LPS-induced periodontitis was significantly attenuated with HU-308 treatment (LPS+HU), measured by macroscopic and histologic examination. Treatment also reduced gingival production of inflammatory mediators augmented in LPS-injected rats, such as: 1) inducible nitric oxide (iNOS) activity (LPS: 90.18 ± 36.51 pmol/minute/mg protein versus LPS+HU: 16.37 ± 4.73 pmol/minute/mg protein; P periodontitis on the salivary secretory response to pilocarpine. Moreover, iNOS activity and PGE2 content, which were increased by LPS-induced periodontitis in the submandibular gland, returned to control values after HU-308 treatment. This study demonstrates anti-inflammatory, osteoprotective, and prohomeostatic effects of HU-308 in oral tissues of rats with LPS-induced periodontitis.

  2. High-affinity cannabinoid binding site in brain: A possible marijuana receptor

    International Nuclear Information System (INIS)

    Nye, J.S.

    1988-01-01

    The mechanism by which delta 9 tetrahydrocannabinol (delta 9 THC), the major psychoactive component of marijuana or hashish, produces its potent psychological and physiological effects is unknown. To find receptor binding sites for THC, we designed a water-soluble analog for use as a radioligand. 5'-Trimethylammonium-delta 8 THC (TMA) is a positively charged analog of delta- 8 THC modified on the 5' carbon, a portion of the molecule not important for its psychoactivity. We have studied the binding of [ 3 H]-5'-trimethylammonium-delta- 8 THC ([ 3 H]TMA) to rat neuronal membranes. [ 3 H]TMA binds saturably and reversibly to brain membranes with high affinity to apparently one class of sites. Highest binding site density occurs in brain, but several peripheral organs also display specific binding. Detergent solubilizes the sites without affecting their pharmacologial properties. Molecular sieve chromatography reveals a bimodal peak of [ 3 H]TMA binding activity of approximately 60,000 daltons apparent molecular weight

  3. Repeated Exposure to the “Spice” Cannabinoid JWH-018 Induces Tolerance and Enhances Responsiveness to 5-HT1A Receptor Stimulation in Male Rats

    Directory of Open Access Journals (Sweden)

    Joshua S. Elmore

    2018-02-01

    Full Text Available Naphthalen-1-yl-(1-pentylindol-3-ylmethanone (JWH-018 is a synthetic compound found in psychoactive “spice” products that activates cannabinoid receptors. Preclinical evidence suggests that exposure to synthetic cannabinoids increases 5-HT2A/2C receptor function in the brain, an effect which might contribute to psychotic symptoms. Here, we hypothesized that repeated exposures to JWH-018 would enhance behavioral responsiveness to the 5-HT2A/2C receptor agonist DOI. Male Sprague-Dawley rats fitted with subcutaneously (sc temperature transponders received daily injections of JWH-018 (1.0 mg/kg, sc or its vehicle for seven consecutive days. Body temperature and catalepsy scores were determined at 1, 2, and 4 h post-injection each day. At 1 and 7 days after the final repeated treatment, rats received a challenge injection of either DOI (0.1 mg/kg, sc or the 5-HT1A receptor agonist 8-OH-DPAT (0.3 mg/kg, sc, then temperature and behavioral responses were assessed. Behaviors induced by DOI included wet dog shakes and back muscle contractions (i.e., skin jerks, while behaviors induced by 8-OH-DPAT included ambulation, forepaw treading, and flat body posture. On the first day of repeated treatment, JWH-018 produced robust hypothermia and catalepsy which lasted up to 4 h, and these effects were significantly blunted by day 7 of treatment. Repeated exposure to JWH-018 did not affect behaviors induced by DOI, but behavioral and hypothermic responses induced by 8-OH-DPAT were significantly augmented 1 day after cessation of JWH-018 treatment. Collectively, our findings show that repeated treatment with JWH-018 produces tolerance to its hypothermic and cataleptic effects, which is accompanied by transient enhancement of 5-HT1A receptor sensitivity in vivo.

  4. Immunohistochemical characterisation and localisation of cannabinoid CB1 receptor protein in the rat vestibular nucleus complex and the effects of unilateral vestibular deafferentation.

    Science.gov (United States)

    Ashton, John C; Zheng, Yiwen; Liu, Ping; Darlington, Cynthia L; Smith, Paul F

    2004-09-24

    CB1 receptor expression has been reported to be low in the brainstem compared with the forebrain, and low in the vestibular nucleus complex (VNC) compared with other regions in the brainstem. However, a frequent effect of cannabis is dizziness and loss of balance. This may be due to the activation of cannabinoid receptors in the central vestibular pathways. We used immunohistochemistry to study the distribution of CB1 receptor protein in the VNC, and Western blotting to measure CB1 receptor expression in the VNC following unilateral vestibular deafferentation (UVD); the hippocampal CA1, CA2/3 and dentate gyrus (DG) regions were also analysed for comparison. This study confirms a previous electrophysiological demonstration that CB1 receptors exist in significant densities in the VNC and are likely to contribute to the neurochemical control of the vestibular reflexes. Nonetheless, CB1 receptor expression did not change significantly in the VNC during vestibular compensation. In addition, despite some small but significant changes in CB1 receptor expression in the CA2/3 and the DG following UVD, in no case were these differences statistically significant in comparison to both control groups.

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

    OpenAIRE

    Serpa, Andr?; Correia, Sara; Ribeiro, Joaquim A.; Sebasti?o, Ana M.; Cascalheira, Jos? F.

    2015-01-01

    Adenosine A1 and cannabinoid CB1 receptors are highly expressed in hippocampus where they trigger similar transduction pathways. We investigated how the combined acute activation of A1 and CB1 receptors modulates cAMP accumulation in rat hippocampal slices. The CB1 agonist WIN55212-2 (0.3?30??M) decreased forskolin-stimulated cAMP accumulation with an EC50 of 6.6 ? 2.7??M and an E max? of 31% ? 2%, whereas for the A1 agonist, N6-cyclopentyladenosine (CPA, 10?150?nM), an EC50 of 35 ? 19?nM, an...

  6. From adolescent to elder rats: Motivation for palatable food and cannabinoids receptors.

    Science.gov (United States)

    Amancio-Belmont, Octavio; Romano-López, Antonio; Ruiz-Contreras, Alejandra Evelin; Méndez-Díaz, Mónica; Prospéro-García, Oscar

    2017-09-01

    To analyze motivation, food self-administration and decision-making were evaluated in adolescent, adult, and aged rats. Subjects were trained to press a lever (fixed ratio, FR1 and FR5) in an operant chamber, to obtain chocolate flavor pellets. They assessed the progressive ratio (PR), extinction, and reinstatement of the behavior. To estimate decision-making for food, rats were trained in the conditioned place preference (CPP) paradigm: (a) associating one compartment with lab chow (LCh) one day and the other compartment with rice krisspies (RK), the next day. (b) Training similar to (a) but on the day RK was the reinforcer, it was delivered with a progressive delay. In addition, CB1 and CB2 receptor expression in the nucleus accumbens (NAcc) and prefrontal cortex (PFC) was estimated by means of Western blot. Adolescent rats consumed higher amounts of RK/body weight than adult and aged rats during FR1, FR5, and PR. Extinction was more prolonged for adolescent rats than for adult and aged rats. First CPP condition, all three groups of rats preferred the RK-associated compartment. Second CPP condition, adolescent rats developed equal preference to both compartments, while adult and aged rats preferred the RK-associated compartment. Rats per group ate a similar amount of either reinforcer. Adolescent rats exhibited low expression of CB1R in the NAcc and low expression of both CB1R and CB2R in the PFC compared with adult and aged rats. Adolescent rats display higher motivation for palatable food and an indiscriminate seeking behavior suggesting involvement of both homeostatic and hedonic systems in their decision-making processes. © 2016 Wiley Periodicals, Inc. Develop Neurobiol 77: 917-927, 2017. © 2016 Wiley Periodicals, Inc.

  7. Cannabinoids for treatment of Alzheimer’s disease: moving towards the clinic

    Directory of Open Access Journals (Sweden)

    Isidro eFerrer

    2014-03-01

    Full Text Available The limited effectiveness of current therapies against Alzheimer’s disease highlights the need for intensifying research efforts devoted to developing new agents for preventing or retarding the disease process. During the last few years, targeting the endogenous cannabinoid system has emerged as a potential therapeutic approach to treat Alzheimer. The endocannabinoid system is composed by a number of cannabinoid receptors, including the well-characterized CB1 and CB2 receptors, with their endogenous ligands and the enzymes related to the synthesis and degradation of these endocannabinoid compounds. Several findings indicate that the activation of both CB1 and CB2 receptors by natural or synthetic agonists, at non-psychoactive doses, have beneficial effects in Alzheimer experimental models by reducing the harmful A peptide action and tau phosphorylation, as well as by promoting the brain’s intrinsic repair mechanisms. Moreover, endocannabinoid signaling has been demonstrated to modulate numerous concomitant pathological processes, including neuroinflammation, excitotoxicity, mitochondrial dysfunction, and oxidative stress. The present paper summarizes the main experimental studies demonstrating the polyvalent properties of cannabinoid compounds for the treatment of Alzheimer’s disease, which together encourage progress towards a clinical trial.

  8. Dopamine D(1) receptor-mediated control of striatal acetylcholine release by endogenous dopamine.

    Science.gov (United States)

    Acquas, E; Di Chiara, G

    1999-10-27

    The role of dopamine D(1) and D(2) receptors in the control of acetylcholine release in the dorsal striatum by endogenous dopamine was investigated by monitoring with microdialysis the effect of the separate or combined administration of the dopamine D(1) receptor antagonist, SCH 39166 ¿(-)-trans-6,7,7a,8,9, 13b-exahydro-3-chloro-2-hydroxy-N-methyl-5H-benzo-[d]-nap hto-[2, 1b]-azepine hydrochloride¿ (50 microg/kg subcutaneous (s.c.)), of the dopamine D(2)/D(3) receptor agonist, quinpirole (trans-(-)-4aR, 4a,5,6,7,8,8a,9-octahydro-5-propyl-1H-pyrazolo-(3,4-g)-quinoline hydrochloride) (5 and 10 microg/kg s.c.), and of the D(3) receptor selective agonist, PD 128,907 [S(+)-(4aR,10bR)-3,4,4a, 10b-tetrahydro-4-propyl-2H,5H-[1]benzopyrano-[4,3-b]-1,4-oxazin -9-ol hydrochloride] (50 microg/kg s.c.), on in vivo dopamine and acetylcholine release. Microdialysis was performed with a Ringer containing low concentrations (0.01 microM) of the acetylcholinesterase inhibitor, neostigmine. Quinpirole (10 microg/kg s.c.) decreased striatal dopamine and acetylcholine release. Administration of PD 128,907 (50 microg/kg) decreased dopamine but failed to affect acetylcholine release. SCH 39166 (50 microg/kg s.c.) stimulated dopamine release and reduced acetylcholine release. Pretreatment with quinpirole reduced (5 microg/kg s.c.) or completely prevented (10 microg/kg s.c.) the stimulation of dopamine release elicited by SCH 39166 (50 microg/kg s.c.); on the other hand, pretreatment with quinpirole (5 and 10 microg/kg) potentiated the reduction of striatal acetylcholine release induced by SCH 39166 (50 microg/kg s.c.). Similarly, pretreatment with PD 128,907 (50 microg/kg) which prevented the increase of dopamine release induced by SCH 39166 (50 microg/kg), potentiated the reduction of striatal acetylcholine transmission elicited by SCH 39166. Thus, pretreatment with low doses of quinpirole or PD 128,907 influences in opposite manner the effect of SCH 39166 on striatal dopamine and

  9. GABAergic and cortical and subcortical glutamatergic axon terminals contain CB1 cannabinoid receptors in the ventromedial nucleus of the hypothalamus.

    Directory of Open Access Journals (Sweden)

    Leire Reguero

    Full Text Available BACKGROUND: Type-1 cannabinoid receptors (CB(1R are enriched in the hypothalamus, particularly in the ventromedial hypothalamic nucleus (VMH that participates in homeostatic and behavioral functions including food intake. Although CB(1R activation modulates excitatory and inhibitory synaptic transmission in the brain, CB(1R contribution to the molecular architecture of the excitatory and inhibitory synaptic terminals in the VMH is not known. Therefore, the aim of this study was to investigate the precise subcellular distribution of CB(1R in the VMH to better understand the modulation exerted by the endocannabinoid system on the complex brain circuitries converging into this nucleus. METHODOLOGY/PRINCIPAL FINDINGS: Light and electron microscopy techniques were used to analyze CB(1R distribution in the VMH of CB(1R-WT, CB(1R-KO and conditional mutant mice bearing a selective deletion of CB(1R in cortical glutamatergic (Glu-CB(1R-KO or GABAergic neurons (GABA-CB(1R-KO. At light microscopy, CB(1R immunolabeling was observed in the VMH of CB(1R-WT and Glu-CB(1R-KO animals, being remarkably reduced in GABA-CB(1R-KO mice. In the electron microscope, CB(1R appeared in membranes of both glutamatergic and GABAergic terminals/preterminals. There was no significant difference in the percentage of CB(1R immunopositive profiles and CB(1R density in terminals making asymmetric or symmetric synapses in CB(1R-WT mice. Furthermore, the proportion of CB(1R immunopositive terminals/preterminals in CB(1R-WT and Glu-CB(1R-KO mice was reduced in GABA-CB(1R-KO mutants. CB(1R density was similar in all animal conditions. Finally, the percentage of CB(1R labeled boutons making asymmetric synapses slightly decreased in Glu-CB(1R-KO mutants relative to CB(1R-WT mice, indicating that CB(1R was distributed in cortical and subcortical excitatory synaptic terminals. CONCLUSIONS/SIGNIFICANCE: Our anatomical results support the idea that the VMH is a relevant hub candidate in

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

    Directory of Open Access Journals (Sweden)

    David R Powell

    2015-06-01

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

  11. Involvement of the cannabinoid CB1 receptor in modulation of dopamine output in the prefrontal cortex associated with food restriction in rats.

    Science.gov (United States)

    Dazzi, Laura; Talani, Giuseppe; Biggio, Francesca; Utzeri, Cinzia; Lallai, Valeria; Licheri, Valentina; Lutzu, Stefano; Mostallino, Maria Cristina; Secci, Pietro Paolo; Biggio, Giovanni; Sanna, Enrico

    2014-01-01

    Increase in dopamine output on corticolimbic structures, such as medial prefrontal cortex (mPFC) and nucleus accumbens, has been related to reward effects associated with palatable food or food presentation after a fasting period. The endocannabinoid system regulates feeding behavior through a modulatory action on different neurotransmitter systems, including the dopaminergic system. To elucidate the involvement of type 1 cannabinoid receptors in the regulation of dopamine output in the mPFC associated with feeding in hungry rats, we restricted the food availability to a 2-h period daily for 3 weeks. In food-restricted rats the extracellular dopamine concentration in the mPFC increased starting 80 min before food presentation and returned to baseline after food removal. These changes were attenuated in animals treated with the CB1 receptor antagonist SR141716. To better understand how food restriction can change the response of mesocortical dopaminergic neurons, we studied several components of the neuronal circuit that regulates dopamine output in the mPFC. Patch-clamp experiments revealed that the inhibitory effect of the CB1 receptor agonist WIN 55,212-2 on GABAergic sIPSC frequency was diminished in mPFC neurons of FR compared to fed ad libitum rats. The basal sIPSC frequency resulted reduced in mPFC neurons of food-restricted rats, suggestive of an altered regulation of presynaptic GABA release; these changes were accompanied by an enhanced excitability of mPFC and ventral tegmental area neurons. Finally, type 1 cannabinoid receptor expression in the mPFC was reduced in food-restricted rats. Together, our data support an involvement of the endocannabinoid system in regulation of dopamine release in the mPFC through changes in GABA inhibitory synapses and suggest that the emphasized feeding-associated increase in dopamine output in the mPFC of food-restricted rats might be correlated with an altered expression and function of type 1 cannabinoid receptor in this

  12. Involvement of the cannabinoid CB1 receptor in modulation of dopamine output in the prefrontal cortex associated with food restriction in rats.

    Directory of Open Access Journals (Sweden)

    Laura Dazzi

    Full Text Available Increase in dopamine output on corticolimbic structures, such as medial prefrontal cortex (mPFC and nucleus accumbens, has been related to reward effects associated with palatable food or food presentation after a fasting period. The endocannabinoid system regulates feeding behavior through a modulatory action on different neurotransmitter systems, including the dopaminergic system. To elucidate the involvement of type 1 cannabinoid receptors in the regulation of dopamine output in the mPFC associated with feeding in hungry rats, we restricted the food availability to a 2-h period daily for 3 weeks. In food-restricted rats the extracellular dopamine concentration in the mPFC increased starting 80 min before food presentation and returned to baseline after food removal. These changes were attenuated in animals treated with the CB1 receptor antagonist SR141716. To better understand how food restriction can change the response of mesocortical dopaminergic neurons, we studied several components of the neuronal circuit that regulates dopamine output in the mPFC. Patch-clamp experiments revealed that the inhibitory effect of the CB1 receptor agonist WIN 55,212-2 on GABAergic sIPSC frequency was diminished in mPFC neurons of FR compared to fed ad libitum rats. The basal sIPSC frequency resulted reduced in mPFC neurons of food-restricted rats, suggestive of an altered regulation of presynaptic GABA release; these changes were accompanied by an enhanced excitability of mPFC and ventral tegmental area neurons. Finally, type 1 cannabinoid receptor expression in the mPFC was reduced in food-restricted rats. Together, our data support an involvement of the endocannabinoid system in regulation of dopamine release in the mPFC through changes in GABA inhibitory synapses and suggest that the emphasized feeding-associated increase in dopamine output in the mPFC of food-restricted rats might be correlated with an altered expression and function of type 1

  13. The anabolic steroid nandrolone alters cannabinoid self-administration and brain CB1 receptor density and function

    NARCIS (Netherlands)

    Struik, Dicky; Fadda, Paola; Zara, Tamara; Zamberletti, Erica; Rubino, Tiziana; Parolaro, Daniela; Fratta, Walter; Fattore, Liana

    Clinical and pre-clinical observations indicate that anabolic-androgenic steroids can induce neurobiological changes that alter the rewarding effects of drugs of abuse. In this study, we investigated the effect of the anabolic steroid nandrolone on the rewarding properties of the cannabinoid CBI

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

    DEFF Research Database (Denmark)

    Manera, Clementina; Saccomanni, Giuseppe; Adinolfi, Barbara

    2009-01-01

    The CB(2) receptor activation can be exploited for the treatment of diseases such as chronic pain and tumors of immune origin, devoid of psychotropic activity. On the basis of our already reported 1,8-naphthyridin-4(1H)-on-3-carboxamide derivatives, new 1,8-naphthyridin-2(1H)-on-3-carboxamide......-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....... derivatives were designed, synthesized, and tested for their affinities toward the human CB(1) and CB(2) cannabinoid receptors. Some of the reported compounds showed a subnanomolar CB(2) affinity with a CB(1)/CB(2) selectivity ratio greater than 200 (compounds 6, 12, cis-12, 13, and cis-13). Further studies...

  15. Synthesis and preliminary biological evaluation of [{sup 123}I]Me{sub 2}Pyr, a new potential ligand for imaging of central cannabinoid CB{sub 1} receptors

    Energy Technology Data Exchange (ETDEWEB)

    Gielow, P. [Department of Nuclear Medicine, University School of Medicine, Carl-Neuberg-Str. 1, D-30625 Hannover (Germany)]. E-mail: gielow.peter@mh-hannover.de; Klinge, P. [International Neuroscience Institute, Alexis Carrel Str. 4, D-30625 Hannover (Germany); Knapp, W.H. [Department of Nuclear Medicine, University School of Medicine, Carl-Neuberg-Str. 1, D-30625 Hannover (Germany); Berding, G. [Department of Nuclear Medicine, University School of Medicine, Carl-Neuberg-Str. 1, D-30625 Hannover (Germany)

    2006-07-15

    A synthesis of 1-(2,4-dichlorophenyl)-5-(4-[{sup 123}I]iodophenyl)-4-methyl-1H-pyrazole -3-carboxylic acid N',N'-dimethyl-hydrazide ([{sup 123}I]Me{sub 2}Pyr), a new radioiodinated analogue of the high-affinity cannabinoid CB{sub 1} receptor antagonist SR141716A, is described. Labelling was achieved by radioiododestannylation of the tributylstannyl precursor with [{sup 123}I]iodide in the presence of chloramine T. HPLC purification afforded the labelled product in 48% radiochemical yield. Preliminary rat brain biodistribution studies with the {sup 125}I labelled compound revealed high uptake in the substantia nigra, the globus pallidus externus and the cerebellum, which is consistent with the known distribution of CB{sub 1} receptors.

  16. 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.

  17. Structural basis of G protein-coupled receptor-Gi protein interaction: formation of the cannabinoid CB2 receptor-Gi protein complex.

    Science.gov (United States)

    Mnpotra, Jagjeet S; Qiao, Zhuanhong; Cai, Jian; Lynch, Diane L; Grossfield, Alan; Leioatts, Nicholas; Hurst, Dow P; Pitman, Michael C; Song, Zhao-Hui; Reggio, Patricia H

    2014-07-18

    In this study, we applied a comprehensive G protein-coupled receptor-Gαi protein chemical cross-linking strategy to map the cannabinoid receptor subtype 2 (CB2)-Gαi interface and then used molecular dynamics simulations to explore the dynamics of complex formation. Three cross-link sites were identified using LC-MS/MS and electrospray ionization-MS/MS as follows: 1) a sulfhydryl cross-link between C3.53(134) in TMH3 and the Gαi C-terminal i-3 residue Cys-351; 2) a lysine cross-link between K6.35(245) in TMH6 and the Gαi C-terminal i-5 residue, Lys-349; and 3) a lysine cross-link between K5.64(215) in TMH5 and the Gαi α4β6 loop residue, Lys-317. To investigate the dynamics and nature of the conformational changes involved in CB2·Gi complex formation, we carried out microsecond-time scale molecular dynamics simulations of the CB2 R*·Gαi1β1γ2 complex embedded in a 1-palmitoyl-2-oleoyl-phosphatidylcholine bilayer, using cross-linking information as validation. Our results show that although molecular dynamics simulations started with the G protein orientation in the β2-AR*·Gαsβ1γ2 complex crystal structure, the Gαi1β1γ2 protein reoriented itself within 300 ns. Two major changes occurred as follows. 1) The Gαi1 α5 helix tilt changed due to the outward movement of TMH5 in CB2 R*. 2) A 25° clockwise rotation of Gαi1β1γ2 underneath CB2 R* occurred, with rotation ceasing when Pro-139 (IC-2 loop) anchors in a hydrophobic pocket on Gαi1 (Val-34, Leu-194, Phe-196, Phe-336, Thr-340, Ile-343, and Ile-344). In this complex, all three experimentally identified cross-links can occur. These findings should be relevant for other class A G protein-coupled receptors that couple to Gi proteins. © 2014 by The American Society for Biochemistry and Molecular Biology, Inc.

  18. Methemoglobin Is an Endogenous Toll-Like Receptor 4 Ligand—Relevance to Subarachnoid Hemorrhage

    Directory of Open Access Journals (Sweden)

    Min Seong Kwon

    2015-03-01

    Full Text Available Neuroinflammation is a well-recognized consequence of subarachnoid hemorrhage (SAH, and may be responsible for important complications of SAH. Signaling by Toll-like receptor 4 (TLR4-mediated nuclear factor κB (NFκB in microglia plays a critical role in neuronal damage after SAH. Three molecules derived from erythrocyte breakdown have been postulated to be endogenous TLR4 ligands: methemoglobin (metHgb, heme and hemin. However, poor water solubility of heme and hemin, and lipopolysaccharide (LPS contamination have confounded our understanding of these molecules as endogenous TLR4 ligands. We used a 5-step process to obtain highly purified LPS-free metHgb, as confirmed by Fourier Transform Ion Cyclotron Resonance mass spectrometry and by the Limulus amebocyte lysate assay. Using this preparation, we show that metHgb is a TLR4 ligand at physiologically relevant concentrations. metHgb caused time- and dose-dependent secretion of the proinflammatory cytokine, tumor necrosis factor α (TNFα, from microglial and macrophage cell lines, with secretion inhibited by siRNA directed against TLR4, by the TLR4-specific inhibitors, Rs-LPS and TAK-242, and by anti-CD14 antibodies. Injection of purified LPS-free metHgb into the rat subarachnoid space induced microglial activation and TNFα upregulation. Together, our findings support the hypothesis that, following SAH, metHgb in the subarachnoid space can promote widespread TLR4-mediated neuroinflammation.

  19. Prevention of drug priming- and cue-induced reinstatement of MDMA-seeking behaviors by the CB1 cannabinoid receptor antagonist AM251.

    Science.gov (United States)

    Nawata, Yoko; Kitaichi, Kiyoyuki; Yamamoto, Tsuneyuki

    2016-03-01

    3,4-Methylenedioxymethamphetamine (MDMA), a methamphetamine (METH) derivative, exhibits METH-like actions at monoamine transporters and positive reinforcing effects in rodents and primates. The purposes of the present study were to determine whether cross-reinstatement would be observed between MDMA and METH and if the cannabinoid receptor, a receptor known to play critical roles in the brain reward system, could modulate MDMA craving. Rats were trained to press a lever for intravenous MDMA (0.3mg/infusion) or METH (0.02mg/infusion) infusions under a fixed ratio 1 schedule paired with drug-associated cues (light and tone). Following drug self-administration acquisition training, rats underwent extinction training (an infusion of saline). Reinstatement tests were performed once the extinction criteria were achieved. In MDMA-trained rats, the MDMA-priming injection (3.2mg/kg, i.p.) or re-exposure to MDMA-associated cues reinstated MDMA-seeking behavior. Additionally, a priming injection of METH (1.0mg/kg, i.p.) also reinstated MDMA-seeking behavior. In contrast, none of the MDMA doses reinstated METH-seeking behavior in the METH-trained rats. The CB1 cannabinoid receptor antagonist AM251 markedly attenuated the MDMA-seeking behaviors induced by MDMA-priming injection or re-exposure to MDMA-associated cues in a dose-dependent manner. These findings show that MDMA has obvious addictive potential for reinstating drug-seeking behavior and that METH can be an effective stimulus for reinstating MDMA-seeking behaviors. Furthermore, based on the attenuating effect of AM251 in the reinstatement of MDMA-seeking behaviors, drugs that suppress CB1 receptors may be used in treatment of MDMA dependence. Copyright © 2016. Published by Elsevier Ireland Ltd.

  20. An endogenous aryl hydrocarbon receptor ligand inhibits proliferation and migration of human ovarian cancer cells.

    Science.gov (United States)

    Wang, Kai; Li, Yan; Jiang, Yi-Zhou; Dai, Cai-Feng; Patankar, Manish S; Song, Jia-Sheng; Zheng, Jing

    2013-10-28

    The aryl hydrocarbon receptor (AhR), a ligand-activated transcription factor mediates many biological processes. Herein, we investigated if 2-(1'H-indole-3'-carbonyl)-thiazole-4-carboxylic acid methyl ester (ITE, an endogenous AhR ligand) regulated proliferation and migration of human ovarian cancer cells via AhR. We found that AhR was widely present in many histotypes of ovarian cancer tissues. ITE suppressed OVCAR-3 cell proliferation and SKOV-3 cell migration in vitro, which were blocked by AhR knockdown. ITE also suppressed OVCAR-3 cell growth in mice. These data suggest that the ITE might potentially be used for therapeutic intervention for at least a subset of human ovarian cancer. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  1. Potential upstream regulators of cannabinoid receptor 1 signaling in prostate cancer: a Bayesian network analysis of data from a tissue microarray.

    Science.gov (United States)

    Häggström, Jenny; Cipriano, Mariateresa; Forshell, Linus Plym; Persson, Emma; Hammarsten, Peter; Stella, Nephi; Fowler, Christopher J

    2014-08-01

    The endocannabinoid system regulates cancer cell proliferation, and in prostate cancer a high cannabinoid CB1 receptor expression is associated with a poor prognosis. Down-stream mediators of CB1 receptor signaling in prostate cancer are known, but information on potential upstream regulators is lacking. Data from a well-characterized tumor tissue microarray were used for a Bayesian network analysis using the max-min hill-climbing method. In non-malignant tissue samples, a directionality of pEGFR (the phosphorylated form of the epidermal growth factor receptor) → CB1 receptors were found regardless as to whether the endocannabinoid metabolizing enzyme fatty acid amide hydrolase (FAAH) was included as a parameter. A similar result was found in the tumor tissue, but only when FAAH was included in the analysis. A second regulatory pathway, from the growth factor receptor ErbB2 → FAAH was also identified in the tumor samples. Transfection of AT1 prostate cancer cells with CB1 receptors induced a sensitivity to the growth-inhibiting effects of the CB receptor agonist CP55,940. The sensitivity was not dependent upon the level of receptor expression. Thus a high CB1 receptor expression alone does not drive the cells towards a survival phenotype in the presence of a CB receptor agonist. The data identify two potential regulators of the endocannabinoid system in prostate cancer and allow the construction of a model of a dysregulated endocannabinoid signaling network in this tumor. Further studies should be designed to test the veracity of the predictions of the network analysis in prostate cancer and other solid tumors. © 2014 The Authors. The Prostate published by Wiley Periodicals, Inc.

  2. Novel protective role of endogenous cardiac myocyte P2X4 receptors in heart failure.

    Science.gov (United States)

    Yang, Tiehong; Shen, Jian-bing; Yang, Ronghua; Redden, John; Dodge-Kafka, Kimberly; Grady, James; Jacobson, Kenneth A; Liang, Bruce T

    2014-05-01

    Heart failure (HF), despite continuing progress, remains a leading cause of mortality and morbidity. P2X4 receptors (P2X4R) have emerged as potentially important molecules in regulating cardiac function and as potential targets for HF therapy. Transgenic P2X4R overexpression can protect against HF, but this does not explain the role of native cardiac P2X4R. Our goal is to define the physiological role of endogenous cardiac myocyte P2X4R under basal conditions and during HF induced by myocardial infarction or pressure overload. Mice established with conditional cardiac-specific P2X4R knockout were subjected to left anterior descending coronary artery ligation-induced postinfarct or transverse aorta constriction-induced pressure overload HF. Knockout cardiac myocytes did not show P2X4R by immunoblotting or by any response to the P2X4R-specific allosteric enhancer ivermectin. Knockout hearts showed normal basal cardiac function but depressed contractile performance in postinfarct and pressure overload models of HF by in vivo echocardiography and ex vivo isolated working heart parameters. P2X4R coimmunoprecipitated and colocalized with nitric oxide synthase 3 (eNOS) in wild-type cardiac myocytes. Mice with cardiac-specific P2X4R overexpression had increased S-nitrosylation, cyclic GMP, NO formation, and were protected from postinfarct and pressure overload HF. Inhibitor of eNOS, L-N(5)-(1-iminoethyl)ornithine hydrochloride, blocked the salutary effect of cardiac P2X4R overexpression in postinfarct and pressure overload HF as did eNOS knockout. This study establishes a new protective role for endogenous cardiac myocyte P2X4R in HF and is the first to demonstrate a physical interaction between the myocyte receptor and eNOS, a mediator of HF protection. © 2014 American Heart Association, Inc.

  3. Fatty Acid Amide Hydrolase (FAAH) Inhibition Enhances Memory Acquisition through Activation of PPAR-alpha Nuclear Receptors

    Science.gov (United States)

    Mazzola, Carmen; Medalie, Julie; Scherma, Maria; Panlilio, Leigh V.; Solinas, Marcello; Tanda, Gianluigi; Drago, Filippo; Cadet, Jean Lud; Goldberg, Steven R.; Yasar, Sevil

    2009-01-01

    Inhibitors of fatty acid amide hydrolase (FAAH) increase endogenous levels of anandamide (a cannabinoid CB[subscript 1]-receptor ligand) and oleoylethanolamide and palmitoylethanolamide (OEA and PEA, ligands for alpha-type peroxisome proliferator-activated nuclear receptors, PPAR-alpha) when and where they are naturally released in the brain.…

  4. Effects of the cannabinoid CB1 receptor agonist CP55,940 and antagonist SR141716A on d-amphetamine-induced behaviours in Cebus monkeys

    DEFF Research Database (Denmark)

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

    2006-01-01

    Several clinical studies have shown that alterations in the cannabinoid system in the brain may be associated with schizophrenia. Although evidence points towards an antipsychotic potential for cannabinoid antagonists, experimental studies have shown inconsistent behavioural effects of cannabinoi...

  5. Cannabinoid CB2 receptors are involved in the protection of RAW264.7 macrophages against the oxidative stress: an in vitro study

    Directory of Open Access Journals (Sweden)

    Sabrina Giacoppo

    2017-01-01

    Full Text Available Research in the last decades has widely investigated the anti-oxidant properties of natural products as a therapeutic approach for the prevention and the treatment of oxidative-stress related disorders. In this context, several studies were aimed to evaluate the therapeutic potential of phytocannabinoids, the bioactive compounds of Cannabis sativa. Here, we examined the anti-oxidant ability of Cannabigerol (CBG, a non-psychotropic cannabinoid, still little known, into counteracting the hydrogen peroxide (H2O2-induced oxidative stress in murine RAW264.7 macrophages. In addition, we tested selective receptor antagonists for cannabinoid receptors and specifically CB1R (SR141716A and CB2R (AM630 in order to investigate through which CBG may exert its action. Taken together, our in vitro results showed that CBG is able to counteract oxidative stress by activation of CB2 receptors. CB2 antagonist pre-treatment indeed blocked the protective effects of CBG in H2O2 stimulated macrophages, while CB1R was not involved. Specifically, CBG exhibited a potent action in inhibiting oxidative stress, by down-regulation of the main oxidative markers (iNOS, nitrotyrosine and PARP-1, by preventing IκB-α phosphorylation and translocation of the nuclear factor-κB (NF-κB and also via the modulation of MAP kinases pathway. On the other hand, CBG was found to increase anti-oxidant defense of cells by modulating superoxide dismutase-1 (SOD-1 expression and thus inhibiting cell death (results focused on balance between Bax and Bcl-2. Based on its antioxidant activities, CBG may hold great promise as an anti-oxidant agent and therefore used in clinical practice as a new approach in oxidative-stress related disorders.

  6. Role of Cannabinoid CB2 Receptor Gene (CNR2) Polymorphism in Children with Immune Thrombocytopenic Purpura in Beni-Suef Governorate in Egypt.

    Science.gov (United States)

    Ezzat, Dina A; Hammam, Amira A; El-Malah, Waleed M; Khattab, Rasha A; Mangoud, Eman M

    2017-01-01

    The cannabinoid system is involved in the immune regulation by modulation of Th cells type 1 and 2. It is composed of the CB2 receptor which is expressed at 10 to 100 folds greater levels on immune cells than the CB1 receptors. The CB2 is encoded by the cannabinoid CB receptor gene (CNR2) gene. This study aims to investigate the polymorphism in CNR2 gene variation rs 35761398 (Q63R) in Egyptian children with immune thrombocytopenic purpura and to investigate the relation between this gene polymorphism and either the susceptibility to or the chronicity of the disease. Forty children diagnosed as ITP were included in this study and 20 healthy children as normal control. CNR2 gene was investigated in those children by PCR RFLP technique (restriction fragment length polymorphism). CNR2 genotyping revealed that 45% of ITP patients had the QR heterotype, 50% had the RR homotype and 5% had QQ, the wild type with significantly higher frequency of homomutant genotype in comparison to controls. The relative odds ratio suggested a double risk for developing ITP in RR homotype (OR 2.152). A significant overpresentation of the RR genotype and of R allele was observed in the chronic patients (P=0.002 and 0.003, respectively). The associated risk to develop chronic ITP increased more than two folds for the RR homotype (OR=2.854). In conclusion, this study confirms the role of CNR2 Q63R polymorphism in the susceptibility to ITP in children and chronicity of the disease. Copyright© by the Egyptian Association of Immunologists.

  7. Total soluble and endogenous secretory receptor for advanced glycation endproducts (RAGE) in IBD.

    Science.gov (United States)

    Meijer, Berrie; Hoskin, Teagan; Ashcroft, Anna; Burgess, Laura; Keenan, Jacqueline I; Falvey, James; Gearry, Richard B; Day, Andrew S

    2014-06-01

    Recruitment and activation of neutrophils, with release of specific proteins such as S100 proteins, is a feature of inflammatory bowel disease (IBD). Soluble forms of the receptor for advanced glycation endproducts (sRAGE), and variants such as endogenous secretory (esRAGE), can act as decoy receptors by binding ligands, including S100A12. The aims of this study were to determine total sRAGE and esRAGE concentrations in patients with IBD and correlate these with C-reactive protein (CRP), endoscopic scores and clinical disease activity scores. EDTA-plasma was collected from patients undergoing colonoscopy including those with Crohn's disease (CD: n=125), ulcerative colitis (UC: n=79) and control patients without endoscopic signs of inflammation (non-IBD: n=156). Concentrations of sRAGE and esRAGE were determined by enzyme-linked immunosorbent assay and plasma CRP concentrations measured. Standard clinical disease activity and endoscopic severity scores were defined for all subjects. Plasma sRAGE concentrations were lower in UC (but not CD) than non-IBD subjects (pdefine the significance of sRAGE and esRAGE in IBD. Copyright © 2013 European Crohn's and Colitis Organisation. Published by Elsevier B.V. All rights reserved.

  8. Delta-9-tetrahydrocannabinol differentially suppresses cisplatin-induced emesis and indices of motor function via cannabinoid CB(1) receptors in the least shrew.

    Science.gov (United States)

    Darmani, N A

    2001-01-01

    We have recently shown that the cannabinoid CB(1) receptor antagonist, SR 141716A, produces emesis in the least shrew (Cryptotis parva) in a dose- and route-dependent manner. This effect was blocked by delta-9-tetrahydrocannabinol (Delta(9)-THC). The present study investigates the cannabinoid receptor mechanisms by which Delta(9)-THC produces its antiemetic effects against cisplatin (20 mg/kg, i.p.)-induced emesis as well as its cannabimimetic activity profile (motor reduction) in the least shrew. Intraperitoneal administration of Delta(9)-THC (1, 2.5, 5 and 10 mg/kg) dose-dependently reduced both the percentage of animals vomiting (ID(50)=1.8+/-1.6 mg/kg) and the frequency of vomits (ID(50)=0.36+/-1.18 mg/kg) in a potent manner. The lowest significantly effective antiemetic dose of Delta(9)-THC for the latter emesis parameters was 2.5 mg/kg. Although Delta(9)-THC reduced the frequency of vomits up to 98%, it failed to completely protect all tested shrews from vomiting (80% protection). The cannabinoid CB(1) antagonist (SR 141716A) and not the CB(2) antagonist (SR 144528), reversed the antiemetic effects of Delta(9)-THC in a dose-dependent fashion. Delta(9)-THC (1, 5, 10 and 20 mg/kg, ip) suppressed locomotor parameters (spontaneous locomotor activity, duration of movement and rearing frequency) in a biphasic manner and only the 20-mg/kg dose simultaneously suppressed the triad of locomotor parameters to a significant degree. Subcutaneous (1-10 mg/kg) and intraperitoneal (0.05-40 mg/kg) injection of some doses of SR 141716A caused significant reductions in one or more components of the triad of locomotor parameters but these reductions were not dose dependent. Subcutaneous injection of SR 141716A (0.2, 1, 5 and 10 mg/kg) reversed the motor suppressant effects of a 20-mg/kg dose of Delta(9)-THC (ip) in a dose-dependent manner. Relative to its motor suppressant effects, Delta(9)-THC is a more potent antiemetic agent. Both effects are probably mediated via CB(1

  9. SPECT imaging of D{sub 2} dopamine receptors and endogenous dopamine release in mice

    Energy Technology Data Exchange (ETDEWEB)

    Jongen, Cynthia [University Medical Center Utrecht, Image Sciences Institute, Q0S.459, P.O. Box 85500, Utrecht (Netherlands); Bruin, Kora de; Booij, Jan [University of Amsterdam, Academic Medical Center, Department of Nuclear Medicine, Amsterdam (Netherlands); Beekman, Freek [University Medical Center Utrecht, Image Sciences Institute, Q0S.459, P.O. Box 85500, Utrecht (Netherlands); University Medical Center Utrecht, Department of Neuroscience and Pharmacology, Utrecht (Netherlands); Technical University Delft, Department R3, Section Radiation, Detection and Matter, Delft (Netherlands)

    2008-09-15

    The dopamine D{sub 2} receptor (D2R) is important in the mediation of addiction. [{sup 123}I]iodobenzamide (IBZM), a SPECT ligand for the D2R, has been used for in vivo studies of D2R availability in humans, monkeys, and rats. Although mouse models are important in the study of addiction, [{sup 123}I]IBZM has not been used in mice SPECT studies. This study evaluates the use of [{sup 123}I]IBZM for measuring D2R availability in mice. Pharmacokinetics of [{sup 123}I]IBZM in mice were studied with pinhole SPECT imaging after intravenous (i.v.) injection of [{sup 123}I]IBZM (20, 40, and 70 MBq). In addition, the ability to measure the release of endogenous dopamine after amphetamine administration with [{sup 123}I]IBZM SPECT was investigated. Thirdly, i.v. administration, the standard route of administration, and intraperitoneal (i.p.) administration of [{sup 123}I]IBZM were compared. Specific binding of [{sup 123}I]IBZM within the mouse striatum could be clearly visualized with SPECT. Peak specific striatal binding ratios were reached around 90 min post-injection. After amphetamine administration, the specific binding ratios of [{sup 123}I]IBZM decreased significantly (-27.2%; n=6; p=0.046). Intravenous administration of [{sup 123}I]IBZM led to significantly higher specific binding than i.p. administration of the same dose. However, we found that i.v. administration of a dose of 70 MBq [{sup 123}I]IBZM might result in acute ethanol intoxication because ethanol is used as a preparative aid for the routine production of [{sup 123}I]IBZM. Imaging of D2R availability and endogenous dopamine release in mice is feasible using [{sup 123}I]IBZM single pinhole SPECT. Using commercially produced [{sup 123}I]IBZM, a dose of 40 MBq injected i.v. can be recommended. (orig.)

  10. SPECT imaging of D2 dopamine receptors and endogenous dopamine release in mice

    International Nuclear Information System (INIS)

    Jongen, Cynthia; Bruin, Kora de; Booij, Jan; Beekman, Freek

    2008-01-01

    The dopamine D 2 receptor (D2R) is important in the mediation of addiction. [ 123 I]iodobenzamide (IBZM), a SPECT ligand for the D2R, has been used for in vivo studies of D2R availability in humans, monkeys, and rats. Although mouse models are important in the study of addiction, [ 123 I]IBZM has not been used in mice SPECT studies. This study evaluates the use of [ 123 I]IBZM for measuring D2R availability in mice. Pharmacokinetics of [ 123 I]IBZM in mice were studied with pinhole SPECT imaging after intravenous (i.v.) injection of [ 123 I]IBZM (20, 40, and 70 MBq). In addition, the ability to measure the release of endogenous dopamine after amphetamine administration with [ 123 I]IBZM SPECT was investigated. Thirdly, i.v. administration, the standard route of administration, and intraperitoneal (i.p.) administration of [ 123 I]IBZM were compared. Specific binding of [ 123 I]IBZM within the mouse striatum could be clearly visualized with SPECT. Peak specific striatal binding ratios were reached around 90 min post-injection. After amphetamine administration, the specific binding ratios of [ 123 I]IBZM decreased significantly (-27.2%; n=6; p=0.046). Intravenous administration of [ 123 I]IBZM led to significantly higher specific binding than i.p. administration of the same dose. However, we found that i.v. administration of a dose of 70 MBq [ 123 I]IBZM might result in acute ethanol intoxication because ethanol is used as a preparative aid for the routine production of [ 123 I]IBZM. Imaging of D2R availability and endogenous dopamine release in mice is feasible using [ 123 I]IBZM single pinhole SPECT. Using commercially produced [ 123 I]IBZM, a dose of 40 MBq injected i.v. can be recommended. (orig.)

  11. 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

    A library of robust ghrelin receptor mutants with single substitutions at 22 positions in the main ligand-binding pocket was employed to map binding sites for six different agonists: two peptides (the 28-amino-acid octanoylated endogenous ligand ghrelin and the hexapeptide growth hormone......, and PheVI:23 on the opposing face of transmembrane domain (TM) VI. Each of the agonists was also affected selectively by specific mutations. The mutational map of the ability of L-692,429 and GHRP-6 to act as allosteric modulators by increasing ghrelin's maximal efficacy overlapped with the common....... It is concluded that although each of the ligands in addition exploits other parts of the receptor, a large, common binding site for both small-molecule agonists--including ago-allosteric modulators--and the endogenous agonist is found on the opposing faces of TM-III and -VI of the ghrelin receptor....

  12. Endogenous plasma estradiol in healthy men is positively correlated with cerebral cortical serotonin 2A receptor binding

    DEFF Research Database (Denmark)

    Frokjaer, Vibe G.; Erritzoe, David; Juul, Anders

    2010-01-01

    the effect of plasma sex hormone levels on neocortical 5-HT2A receptor binding as imaged with [18F]altanserin PET. The effect of endogenous sex-hormone levels was evaluated by multiple linear regression analysis. Results: Mean neocortical 5-HT2A receptor binding was positively correlated with estradiol (p......Background: Sex-hormones influence brain function and are likely to play a role in the gender predisposition to mood and anxiety disorders. Acute fluctuations of sex-hormone levels including hormonal replacement therapy appear to affect serotonergic neurotransmission, but it is unknown if baseline...... levels affect serotonergic neurotransmission. This study was undertaken to examine if baseline levels of endogenous sex hormones are associated with cerebral serotonin 2A (5-HT2A) receptor binding in men. Methods: In a group of 72 healthy men (mean age 37.5 years ±17.4 SD, range 19.6–81.7) we studied...

  13. Endogenous Vascular Endothelial Growth Factor-A (VEGF-A) Maintains Endothelial Cell Homeostasis by Regulating VEGF Receptor-2 Transcription*

    Science.gov (United States)

    E, Guangqi; Cao, Ying; Bhattacharya, Santanu; Dutta, Shamit; Wang, Enfeng; Mukhopadhyay, Debabrata

    2012-01-01

    Vascular endothelial growth factor A (VEGF-A) is one of the most important factors controlling angiogenesis. Although the functions of exogenous VEGF-A have been widely studied, the roles of endogenous VEGF-A remain unclear. Here we focused on the mechanistic functions of endogenous VEGF-A in endothelial cells. We found that it is complexed with VEGF receptor 2 (VEGFR-2) and maintains a basal expression level for VEGFR-2 and its downstream signaling activation. Endogenous VEGF-A also controls expression of key endothelial specific genes including VEGFR-2, Tie-2, and vascular endothelial cadherin. Of importance, endogenous VEGF-A differs from exogenous VEGF-A by regulating VEGFR-2 transcription through mediation of FoxC2 binding to the FOX:ETS motif, and the complex formed by endogenous VEGF-A with VEGFR-2 is localized within the EEA1 (early endosome antigen 1) endosomal compartment. Taken together, our results emphasize the importance of endogenous VEGF-A in endothelial cells by regulating key vascular proteins and maintaining the endothelial homeostasis. PMID:22167188

  14. A Role of Endogenous Progesterone in Stroke Cerebroprotection Revealed by the Neural-Specific Deletion of Its Intracellular Receptors.

    Science.gov (United States)

    Zhu, Xiaoyan; Fréchou, Magalie; Liere, Philippe; Zhang, Shaodong; Pianos, Antoine; Fernandez, Neïké; Denier, Christian; Mattern, Claudia; Schumacher, Michael; Guennoun, Rachida

    2017-11-08

    Treatment with progesterone protects the male and female brain against damage after middle cerebral artery occlusion (MCAO). However, in both sexes, the brain contains significant amounts of endogenous progesterone. It is not known whether endogenously produced progesterone enhances the resistance of the brain to ischemic insult. Here, we used steroid profiling by gas chromatography-tandem mass spectrometry (GC-MS/MS) for exploring adaptive and sex-specific changes in brain levels of progesterone and its metabolites after MCAO. We show that, in the male mouse brain, progesterone is mainly metabolized via 5α-reduction leading to 5α-dihydroprogesterone (5α-DHP), also a progesterone receptor (PR) agonist ligand in neural cells, then to 3α,5α-tetrahydroprogesterone (3α,5α-THP). In the female mouse brain, levels of 5α-DHP and 3α,5α-THP are lower and levels of 20α-DHP are higher than in males. After MCAO, levels of progesterone and 5α-DHP are upregulated rapidly to pregnancy-like levels in the male but not in the female brain. To assess whether endogenous progesterone and 5α-DHP contribute to the resistance of neural cells to ischemic damage, we inactivated PR selectively in the CNS. Deletion of PR in the brain reduced its resistance to MCAO, resulting in increased infarct volumes and neurological deficits in both sexes. Importantly, endogenous PR ligands continue to protect the brain of aging mice. These results uncover the unexpected importance of endogenous progesterone and its metabolites in cerebroprotection. They also reveal that the female reproductive hormone progesterone is an endogenous cerebroprotective neurosteroid in both sexes. SIGNIFICANCE STATEMENT The brain responds to injury with protective signaling and has a remarkable capacity to protect itself. We show here that, in response to ischemic stroke, levels of progesterone and its neuroactive metabolite 5α-dihydroprogesterone are upregulated rapidly in the male mouse brain but not in the

  15. Effects of the cannabinoid-1 receptor antagonist rimonabant on psychiatric symptoms in overweight people with schizophrenia: a randomized, double-blind, pilot study.

    Science.gov (United States)

    Kelly, Deanna L; Gorelick, David A; Conley, Robert R; Boggs, Douglas L; Linthicum, Jared; Liu, Fang; Feldman, Stephanie; Ball, M Patricia; Wehring, Heidi J; McMahon, Robert P; Huestis, Marilyn A; Heishman, Stephen J; Warren, Kimberly R; Buchanan, Robert W

    2011-02-01

    Weight gain is a major adverse effect of several second-generation antipsychotic medications. Rimonabant is a cannabinoid-1 receptor antagonist that promotes weight loss in the general population. We conducted a 16-week, double-blind, placebo-controlled study of rimonabant (20 mg/d) in people with schizophrenia or schizoaffective disorder, based on the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition criteria, who were clinically stable on second-generation antipsychotics. Participants had a body mass index of 27 kg/m or higher with hyperlipidemia or body mass index of 30 kg/m or higher, and no current substance abuse/dependence (except nicotine), more than weekly cannabis use, or recent depressive symptoms/suicidality. An exercise and dietary counseling group was offered weekly. Target enrollment was 60; the trial was terminated early because of withdrawal of rimonabant from the European market. Fifteen participants were randomized (7 rimonabant, 8 placebo); 5 completed in each group. Rimonabant was associated with a greater reduction in Brief Psychiatric Rating Scale total score versus placebo (mean ± SE difference, -1.9 ± 0.8, P = 0.02), driven by differences in the Brief Psychiatric Rating Scale anxiety/depression (-1.4 ± 0.35, P = 0.0004) and hostility (-0.7 ± 0.3, P = 0.02) factors. Group differences were not significant for the Calgary Depression Scale total score (P = 0.24), Scale for the Assessment of Negative Symptoms total score (P = 0.13), weight, blood pressure, or fasting lipids or glucose. Rimonabant was well tolerated with no significant adverse events. No significant weight loss, metabolic effects, or adverse psychiatric effects were associated with the cannabinoid-1 receptor antagonist rimonabant in this small sample of people with schizophrenia. The endocannabinoid system remains a promising target for pharmacotherapy of schizophrenia and obesity.

  16. Role of G1359A polymorphism of the cannabinoid receptor gene on weight loss and adipocytokines levels after two different hypocaloric diets.

    Science.gov (United States)

    Antonio de Luis, Daniel; Sagrado, Manuel Gonzalez; Aller, Rocio; Conde, Rosa; Izaola, Olatz; de la Fuente, Beatriz; Primo, David

    2012-03-01

    A silent intragenic polymorphism (1359 G/A) of the cannabinoid receptor 1 gene resulting in the substitution of the G to A at nucleotide position 1359 in codon 435 (Thr) was reported as a common polymorphism in Caucasian populations. Intervention studies with this polymorphism have not been realized. We decide to investigate the role of missense polymorphism (G1359A) of cannabinoid receptor 1 gene on adipocytokines response and weight loss secondary to a low-fat versus a low-carbohydrate diet in obese patients. A population of 249 patients was analyzed. A nutritional evaluation was performed at the beginning and at the end of a 3-month period in which subjects received one of two diets (diet I: low fat vs. diet II: low carbohydrate). One hundred forty three patients (57.4%) had the genotype G1359G (wild-type group), and 106 (42.6%) patients had G1359A (92 patients, or 36.9%) or A1359A (14 patients, or 5.6%; mutant-type group). With both diets in wild-type and mutant-type groups, body mass index (BMI), weight, fat mass, waist circumference and systolic blood pressure levels decreased. With both diets and in wild-type group, glucose, total cholesterol and insulin levels and homeostasis model assessment test score decreased. No metabolic effects were observed in mutant-type group. Leptin levels decreased significantly in the wild-type group with both diets (diet I: 10.8% vs. diet II: 28.9%; Plow-carbohydrate diet than low-fat diet. Copyright © 2012 Elsevier Inc. All rights reserved.

  17. Blockade of Cannabinoid CB1 Receptors in the Dorsal Periaqueductal Gray Unmasks the Antinociceptive Effect of Local Injections of Anandamide in Mice

    Directory of Open Access Journals (Sweden)

    Diego C. Mascarenhas

    2017-10-01

    Full Text Available Divergent results in pain management account for the growing number of studies aiming at elucidating the pharmacology of the endocannabinoid/endovanilloid anandamide (AEA within several pain-related brain structures. For instance, the stimulation of both Transient Receptor Potential Vanilloid type 1 (TRPV1 and Cannabinoid type 1 (CB1 receptors led to paradoxical effects on nociception. Here, we attempted to propose a clear and reproducible methodology to achieve the antinociceptive effect of exogenous AEA within the dorsal periaqueductal gray (dPAG of mice exposed to the tail-flick test. Accordingly, male Swiss mice received intra-dPAG injection of AEA (CB1/TRPV1 agonist, capsaicin (TRPV1 agonist, WIN (CB1 agonist, AM251 (CB1 antagonist, and 6-iodonordihydrocapsaicin (6-IODO (TRPV1 selective antagonist and their nociceptive response was assessed with the tail-flick test. In order to assess AEA effects on nociception specifically at vanilloid or cannabinoid (CB substrates into the dPAG, mice underwent an intrinsically inactive dose of AM251 or 6-IODO followed by local AEA injections and were subjected to the same test. While intra-dPAG AEA did not change acute pain, local injections of capsaicin or WIN induced a marked TRPV1- and CB1-dependent antinociceptive effect, respectively. Regarding the role of AEA specifically at CB/vanilloid substrates, while the blockade of TRPV1 did not change the lack of effects of intra-dPAG AEA on nociception, local pre-treatment of AM251, a CB1 antagonist, led to a clear AEA-induced antinociception. It seems that the exogenous AEA-induced antinociception is unmasked when it selectively binds to vanilloid substrates, which might be useful to address acute pain in basic and perhaps clinical trials.

  18. 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. Copyright © 2015 Elsevier B.V. All rights reserved.

  19. Nitric oxide-induced calcium release: activation of type 1 ryanodine receptor by endogenous nitric oxide.

    Science.gov (United States)

    Kakizawa, Sho; Yamazawa, Toshiko; Iino, Masamitsu

    2013-01-01

    Ryanodine receptors (RyRs), located in the sarcoplasmic/endoplasmic reticulum (SR/ER) membrane, are required for intracellular Ca2+ release that is involved in a wide range of cellular functions. In addition to Ca2+-induced Ca2+ release in cardiac cells and voltage-induced Ca2+ release in skeletal muscle cells, we recently identified another mode of intracellular Ca2+ mobilization mediated by RyR, i.e., nitric oxide-induced Ca2+ release (NICR), in cerebellar Purkinje cells. NICR is evoked by neuronal activity, is dependent on S-nitrosylation of type 1 RyR (RyR1) and is involved in the induction of long-term potentiation (LTP) of cerebellar synapses. In this addendum, we examined whether peroxynitrite, which is produced by the reaction of nitric oxide with superoxide, may also have an effect on the Ca2+ release via RyR1 and the cerebellar LTP. We found that scavengers of peroxynitrite have no significant effect either on the Ca2+ release via RyR1 or on the cerebellar LTP. We also found that an application of a high concentration of peroxynitrite does not reproduce neuronal activity-dependent Ca2+ release in Purkinje cells. These results support that NICR is induced by endogenous nitric oxide produced by neuronal activity through S-nitrosylation of RyR1.

  20. Cannabinoid receptor expression and phosphorylation are differentially regulated between male and female cerebellum and brain stem after repeated stress: implication for PTSD and drug abuse.

    Science.gov (United States)

    Xing, Guoqiang; Carlton, Janis; Zhang, Lei; Jiang, Xiaolong; Fullerton, Carol; Li, He; Ursano, Robert

    2011-09-08

    Recent study demonstrated a close relationship between cerebellum atrophy and symptom severity of pediatric maltreatment-related posttraumatic stress disorder (PTSD). It has also been known that females are more vulnerable than males in developing anxiety disorders after exposure to traumatic stress. The mechanisms are unknown. Because cannabinoid receptors (CB₁ and CB₂) are neuroprotective and highly expressed in the cerebellum, we investigated cerebellar CB expression in stressed rats. Young male and female Sprague-Dawley rats were given 40 unpredictable electric tail-shocks for 2h daily on 3 consecutive days. CB₁ and CB₂ mRNA and protein levels in rat cerebellum and brain stem were determined using quantitative real-time PCR and Western blot, respectively. Two-way ANOVA revealed significant gender and stress effects on cerebellar CB₁ mRNA expression, with females and non-stressed rats exhibiting higher CB₁ mRNA levels than the males (3 fold, pstressed rats (30%, pstress increased the level of phosphorylated CB₁ receptors, the inactivated CB₁, in rat cerebellum (pstress interaction. Thus, repeated severe stress caused greater CB₁ mRNA suppression and CB₁ receptor phosphorylation in female cerebellum that could lead to increased susceptibility to stress-related anxiety disorders including PTSD. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

  1. EFFECT OF CANNABINOIDS ON TESTICULAR ISCHEMIA-REPERFUSION INJURY IN RAT

    Directory of Open Access Journals (Sweden)

    H. Sepehri

    2006-11-01

    Full Text Available Anandamide is an endogenous ligand for cannabinoid receptors and has endothelial protective effect against ischemic preconditioning. The purpose of this study was to investigate the effects of cannabinoids on reperfusion injury due to testicular torsion-detorsion (T/D. A total of 36 adult male Sprague-Dawley rats were divided into 6 groups. Testicular ischemia was achieved by twisting the right testes 720◦ counters clockwise for 1 hour and reperfusion was allowed for 4 hours after detorsion. In baseline (normal group, bilateral orchiectomies performed after anesthesia. Sham operated group was served as a control group. Torsion/detorsion group underwent 1 hour testicular torsion and 4 hours of detorsion. Anandamide (cannabinoid agonist group received pretreatment with intraperitoneally anandamide 30 min before torsion. AM251 (CB1 antagonist group, received intraperitoneally injection of AM251 45 min before torsion. Anandamid/AM251 (An/AM group received administrations of AM251 45 min before torsion and anandamide 30 min before torsion. The ipsilateral malondialdehyde (MDA level in T/D group were significantly higher versus control and base line groups. Ipsilateral MDA values in anandamid group were significantly lower than T/D and An/AM groups. There were also significant decreases in catalase activity in T/D group compared with control and base line groups. These values were significantly higher in cannabinoid group versus T/D and An/AM groups. Anandamide increased ipsilateral intratesticular antioxidative markers and decreased free radicals formation during reperfusion phase after unilateral testicular torsion, which was reflected in lesser testicular MDA level. Furthermore, the effects of anandamide were mediated via cannabinoid receptors, since AM251 could abolish these effects.

  2. Cannabinoid Hyperemesis Relieved by Compulsive Bathing

    OpenAIRE

    Chang, Yoon Hee; Windish, Donna M.

    2009-01-01

    Cannabinoid hyperemesis is a clinical syndrome characterized by repeated vomiting and associated learned compulsive hot water bathing behavior due to long-term marijuana use. Research has indentified type 1 cannabinoid receptors in the intestinal nerve plexus that have an inhibitory effect on gastrointestinal motility. This inhibitory effect may lead to hyperemesis in marijuana users. The thermoregulatory role of endocannabinoids may be responsible for the patient's need to take hot showers. ...

  3. An investigation into ‘two hit’ effects of BDNF deficiency and young-adult cannabinoid receptor stimulation on prepulse inhibition regulation and memory in mice

    Directory of Open Access Journals (Sweden)

    Maren eKlug

    2013-10-01

    Full Text Available Reduced brain-derived neurotrophic factor (BDNF signalling has been shown in the frontal cortex and hippocampus in schizophrenia. The aim of the present study was to investigate whether a BDNF deficit would modulate effects of chronic cannabis intake, a well-described risk factor for schizophrenia development. BDNF heterozygous mice (HET and wild-type controls were chronically treated during weeks 6, 7 and 8 of life with the cannabinoid CB1 receptor agonist, CP55,940 (CP. After a 2-week delay, there were no CP-induced deficits in any of the groups in short-term spatial memory in a Y-maze task or novel object recognition memory. Baseline prepulse inhibition (PPI was lower but average startle was increased in BDNF HET compared to wild-type controls. Acute CP administration before the PPI session caused a marked increase in PPI in male HET mice pre-treated with CP but not in any of the other male groups. In females, there were small increases of PPI in all groups upon acute CP administration. Acute CP administration furthermore reduced startle and this effect was greater in HET mice irrespective of chronic CP pre-treatment. Analysis of the levels of [3H]CP55,940 binding by autoradiography revealed a significant increase in the nucleus accumbens of male BDNF HET mice previously treated with CP but not in any of the other groups or in the caudate nucleus.These results show that BDNF deficiency and chronic young-adult cannabinoid receptor stimulation do not interact in this model on learning and memory later in life. In contrast, male ‘two hit’ mice, but not females, were hypersensitive to the effect of acute CP on sensorimotor gating. These effects may be related to a selective increase of [3H]CP55,940 binding in the nucleus accumbens, reflecting up-regulation of CB1 receptor density in this region. These data could be of relevance to our understanding of differential ‘two hit’ neurodevelopmental mechanisms in schizophrenia.

  4. Pharmacological Characterization of 30 Human Melanocortin-4 Receptor Polymorphisms with the Endogenous Proopiomelanocortin Derived Agonists, Synthetic Agonists, and the Endogenous Agouti-Related Protein (AGRP) Antagonist

    Science.gov (United States)

    Xiang, Zhimin; Proneth, Bettina; Dirain, Marvin L.; Litherland, Sally A.; Haskell-Luevano, Carrie

    2010-01-01

    The melanocortin-4 receptor (MC4R) is a G-protein coupled receptor (GPCR) that is expressed in the central nervous system and has a role in regulating feeding behavior, obesity, energy homeostasis, male erectile response, and blood pressure. Since the report of the MC4R knockout mouse in 1997, the field has been searching for links between this genetic bio marker and human obesity and type 2 diabetes. More then 80 single nucleotide polymorphisms (SNPs) have been identified from human patients, both obese and non-obese controls. Many significant studies have been performed examining the pharmacological characteristics of these hMC4R SNPs in attempts to identify a molecular defects/insights that might link a genetic factor to the obese phenotype observed in patients possessing these mutations. Our laboratory has previously reported the pharmacological characterization of 40 of these polymorphic hMC4 receptors with multiple endogenous and synthetic ligands. The goal of the current study is to perform a similar comprehensive side-by-side characterization of 30 additional human hMC4R with single nucleotide polymorphisms using multiple endogenous agonists [α-, β, γ2-melanocyte stimulating hormones (MSH) and adrenocorticotropin (ACTH)], the antagonist agouti-related protein hAGRP(87-132), and synthetic agonists [NDP-MSH, MTII, and the tetrapeptide Ac-His-DPhe-Arg-Trp-NH2 (JRH887-9)]. These in vitro data, in some cases, provide a putative molecular link between dysfunctional hMC4R's and human obesity. These 30 hMC4R SNPs include R7H, R18H, R18L, S36Y, P48S, V50M, F51L, E61K, I69T, D90N, S94R, G98R, I121T, A154D, Y157S, W174C, G181D, F202L, A219V, I226T, G231S, G238D, N240S, C271R, S295P, P299L, E308K, I317V, L325F and 750DelGA. All but the N240S hMC4R were identified in obese patients. Additionally, we have characterized a double I102T/V103I hMC4R. In addition to the pharmacological characterization, the hMC4R variants were evaluated for cell surface expression by flow

  5. Pharmacological characterization of 30 human melanocortin-4 receptor polymorphisms with the endogenous proopiomelanocortin-derived agonists, synthetic agonists, and the endogenous agouti-related protein antagonist.

    Science.gov (United States)

    Xiang, Zhimin; Proneth, Bettina; Dirain, Marvin L; Litherland, Sally A; Haskell-Luevano, Carrie

    2010-06-08

    The melanocortin-4 receptor (MC4R) is a G-protein-coupled receptor (GPCR) that is expressed in the central nervous system and has a role in regulating feeding behavior, obesity, energy homeostasis, male erectile response, and blood pressure. Since the report of the MC4R knockout mouse in 1997, the field has been searching for links between this genetic biomarker and human obesity and type 2 diabetes. More then 80 single nucleotide polymorphisms (SNPs) have been identified from human patients, both obese and nonobese controls. Many significant studies have been performed examining the pharmacological characteristics of these hMC4R SNPs in attempts to identify a molecular defects/insights that might link a genetic factor to the obese phenotype observed in patients possessing these mutations. Our laboratory has previously reported the pharmacological characterization of 40 of these polymorphic hMC4 receptors with multiple endogenous and synthetic ligands. The goal of the current study is to perform a similar comprehensive side-by-side characterization of 30 additional human hMC4R with single nucleotide polymorphisms using multiple endogenous agonists [alpha-, beta-, and gamma(2)-melanocyte stimulating hormones (MSH) and adrenocorticotropin (ACTH)], the antagonist agouti-related protein hAGRP(87-132), and synthetic agonists [NDP-MSH, MTII, and the tetrapeptide Ac-His-dPhe-Arg-Trp-NH(2) (JRH887-9)]. These in vitro data, in some cases, provide a putative molecular link between dysfunctional hMC4R's and human obesity. These 30 hMC4R SNPs include R7H, R18H, R18L, S36Y, P48S, V50M, F51L, E61K, I69T, D90N, S94R, G98R, I121T, A154D, Y157S, W174C, G181D, F202L, A219 V, I226T, G231S, G238D, N240S, C271R, S295P, P299L, E308K, I317V, L325F, and 750DelGA. All but the N240S hMC4R were identified in obese patients. Additionally, we have characterized a double I102T/V103I hMC4R. In addition to the pharmacological characterization, the hMC4R variants were evaluated for cell surface

  6. Effects of Chronic Alcohol Exposure on the Modulation of Ischemia-Induced Glutamate Release via Cannabinoid Receptors in the Dorsal Hippocampus.

    Science.gov (United States)

    Zheng, Lei; Wu, Xiaoda; Dong, Xiao; Ding, Xinli; Song, Cunfeng

    2015-10-01

    Chronic alcohol consumption is a critical contributing factor to ischemic stroke, as it enhances ischemia-induced glutamate release, leading to more severe excitotoxicity and brain damage. But the neural mechanisms underlying this phenomenon are poorly understood. We evaluated the effects of chronic alcohol exposure on the modulation of ischemia-induced glutamate release via CB1 and CB2 cannabinoid receptors during middle cerebral artery occlusion, using in vivo microdialysis coupled with high-performance liquid chromatography, in alcohol-naïve rats or rats after 1 or 30 days of withdrawal from chronic ethanol intake (6% v/v for 14 days). Intra-dorsal hippocampus (DH) infusions of ACEA or JWH133, selective CB1 or CB2 receptor agonists, respectively, decreased glutamate release in the DH in alcohol-naïve rats in a dose-dependent manner. Such an effect was reversed by co-infusions of SR141716A or AM630, selective CB1 or CB2 receptor antagonists, respectively. After 30 days, but not 1 day of withdrawal, ischemia induced an enhancement in glutamate release in the DH, as compared with non-alcohol-treated control group. Intra-DH infusions of JWH133, but not ACEA, inhibited ischemia-induced glutamate release in the DH after 30 days of withdrawal. Finally, 1 day of withdrawal did not alter the protein level of CB1 or CB2 receptors in the DH, as compared to non-alcohol-treated control rats. Whereas 30 days of withdrawal robustly decreased the protein level of CB1 receptors, but failed to alter the protein level of CB2 receptors, in the DH, as compared to non-alcohol-treated control rats. Together, these findings suggest that loss of expression/function of CB1 receptors, but not CB2 receptors in the DH, is correlated with the enhancement of ischemia-induced glutamate release after prolonged alcohol withdrawal. Copyright © 2015 by the Research Society on Alcoholism.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2010-08-15

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

  8. Coordinate phosphorylation of insulin-receptor kinase and its 175,000-Mr endogenous substrate in rat hepatocytes

    International Nuclear Information System (INIS)

    Okamoto, M.; Karasik, A.; White, M.F.; Kahn, C.R.

    1991-01-01

    To investigate the early events in insulin signal transmission in liver, isolated rat hepatocytes were labeled with 32 P, and proteins phosphorylated in response to insulin were detected by immunoprecipitation with anti-phosphotyrosine and anti-receptor antibodies and analyzed by sodium dodecyl sulfate (SDS)-polyacrylamide gel electrophoresis and autoradiography. In these cells, insulin rapidly stimulated tyrosine phosphorylation of the 95,000-Mr beta-subunit of the insulin receptor and a 175,000-Mr phosphoprotein (pp175). Both proteins were precipitated by anti-phosphotyrosine antibody, whereas only the insulin receptor was recognized with anti-insulin-receptor antibody. In the insulin-stimulated state, both pp175 and the receptor beta-subunit were found to be phosphorylated on tyrosine and serine residues. Based on precipitation by the two antibodies, receptor phosphorylation was biphasic with an initial increase in tyrosine phosphorylation followed by a more gradual increase in serine phosphorylation over the first 30 min of stimulation. The time course of phosphorylation of pp175 was rapid and paralleled that of the beta-subunit of the insulin receptor. The pp175 was clearly distinguished from the insulin receptor, because it was detected only when boiling SDS was used to extract cellular phosphoproteins, whereas the insulin receptor was extracted with either Triton X-100 or SDS. In addition, the tryptic peptide maps of the two proteins were distinct. The dose-response curve for insulin stimulation was shifted slightly to the left of the insulin receptor, suggesting some signal amplification at this step. These data suggest that pp175 is a major endogenous substrate of the insulin receptor in liver and may be a cytoskeletal-associated protein

  9. Pharmacology of functional endogenous IP prostanoid receptors in NCB-20 cells: comparison with binding data from human platelets.

    Science.gov (United States)

    Crider, J Y; Xu, S X; Sharif, N A

    2001-01-01

    The objective of these studies was to characterize the effects of a broad range of prostanoid agonists upon the stimulation of cAMP production in National Cancer Bank (NCB-20; mouse neuroblastoma/hamster brain hybridoma) cells. The pharmacology of these functional responses in NCB-20 cells was compared with that of the classic endogenous IP receptor present on human platelets using [3H]-iloprost binding techniques. In both assay systems, agonists from the IP prostanoid class exhibited the highest affinities and functional potencies. Specific prostanoids exhibited the following rank order of potency (EC50 +/- SEM) in stimulating cAMP production in the NCB-20 cells: carbaprostacyclin (4.3 +/- 0.9 nM) = PGI2 (6.6 +/-1.5 nM) > iloprost (75+/-13 nM) > 11-deoxy PGE, (378+/-138 nM) > misoprostol (1,243+/-48) > PGE2 (3020+/-700 nM) > ZK-118182 (7265+/-455 nM). Iloprost wasthe most potent compound in the human platelet binding assay while prostanoidsfromthe DPand EP receptor classes showed modest affinity. These studies provide functional and binding information for a broad range of both natural and synthetic prostanoid receptor ligands at the endogenous IP receptor in two different cell types.

  10. An endogenous aryl hydrocarbon receptor ligand acts on dendritic cells and T cells to suppress experimental autoimmune encephalomyelitis

    Science.gov (United States)

    Quintana, Francisco J.; Murugaiyan, Gopal; Farez, Mauricio F.; Mitsdoerffer, Meike; Tukpah, Ann-Marcia; Burns, Evan J.; Weiner, Howard L.

    2010-01-01

    The ligand-activated transcription factor aryl hydrocarbon receptor (AHR) participates in the differentiation of FoxP3+ Treg, Tr1 cells, and IL-17–producing T cells (Th17). Most of our understanding on the role of AHR on the FoxP3+ Treg compartment results from studies using the toxic synthetic chemical 2,3,7,8-tetrachlorodibenzo-p-dioxin. Thus, the physiological relevance of AHR signaling on FoxP3+ Treg in vivo is unclear. We studied mice that carry a GFP reporter in the endogenous foxp3 locus and a mutated AHR protein with reduced affinity for its ligands, and found that AHR signaling participates in the differentiation of FoxP3+ Treg in vivo. Moreover, we found that treatment with the endogenous AHR ligand 2-(1′H-indole-3′-carbonyl)-thiazole-4-carboxylic acid methyl ester (ITE) given parenterally or orally induces FoxP3+ Treg that suppress experimental autoimmune encephalomyelitis. ITE acts not only on T cells, but also directly on dendritic cells to induce tolerogenic dendritic cells that support FoxP3+ Treg differentiation in a retinoic acid-dependent manner. Thus, our work demonstrates that the endogenous AHR ligand ITE promotes the induction of active immunologic tolerance by direct effects on dendritic and T cells, and identifies nontoxic endogenous AHR ligands as potential unique compounds for the treatment of autoimmune disorders. PMID:21068375

  11. Endogenous Glucagon-like Peptide-1 Receptor Signaling in the Nucleus Tractus Solitarius is Required for Food Intake Control.

    Science.gov (United States)

    Alhadeff, Amber L; Mergler, Blake D; Zimmer, Derek J; Turner, Christopher A; Reiner, David J; Schmidt, Heath D; Grill, Harvey J; Hayes, Matthew R

    2017-06-01

    Alhough the glucagon-like peptide-1 (GLP-1) system is critical to energy balance control and is a target for obesity pharmacotherapies, the receptor-population-mediating effects of endogenous GLP-1 signaling are not fully understood. To address this, we developed a novel adeno-associated virus (AAV-GLP-1R) that utilizes short hairpin RNA to chronically knock down GLP-1 receptors (GLP-1R) in rats. As pharmacological studies highlight the hindbrain nucleus tractus solitarius (NTS) as a brain region important for GLP-1R-mediated effects on energy balance, AAV-GLP-1R was injected into the NTS to examine the role of endogenous NTS GLP-1R signaling in energy balance control. Chow intake and meal size were significantly increased following chronic NTS GLP-1R knockdown. In addition, NTS GLP-1R knockdown significantly increased self-administration of palatable food under both fixed and progressive ratio schedules of reinforcement. Collectively, these data demonstrate that endogenous NTS GLP-1R signaling is required for the control of food intake and motivation to feed, and provide a new strategy to investigate the importance of distinct GLP-1R populations in the control of a variety of functions.

  12. Deuterium labeled cannabinoids

    International Nuclear Information System (INIS)

    Driessen, R.A.

    1979-01-01

    Complex reactions involving ring opening, ring closure and rearrangements hamper complete understanding of the fragmentation processes in the mass spectrometric fragmentation patterns of cannabinoids. Specifically labelled compounds are very powerful tools for obtaining more insight into fragmentation mechanisms and ion structures and therefore the synthesis of specifically deuterated cannabinoids was undertaken. For this, it was necessary to investigate the preparation of cannabinoids, appropriately functionalized for specific introduction of deuterium atom labels. The results of mass spectrometry with these labelled cannabinoids are described. (Auth.)

  13. 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.

  14. Oral haloperidol or olanzapine intake produces distinct and region-specific increase in cannabinoid receptor levels that is prevented by high fat diet.

    Science.gov (United States)

    Delis, Foteini; Rosko, Lauren; Shroff, Aditya; Leonard, Kenneth E; Thanos, Panayotis K

    2017-10-03

    Clinical studies show higher levels of cannabinoid CB1 receptors (CB1R) in the brain of schizophrenic patients while preclinical studies report a significant functional interaction between dopamine D2 receptors and CB1Rs as well as an upregulation of CB1Rs after antipsychotic treatment. These findings prompted us to study the effects of chronic oral intake of a first and a second generation antipsychotic, haloperidol and olanzapine, on the levels and distribution of CB1Rs in the rat brain. Rats consumed either regular chow or high-fat food and drank water, haloperidol drinking solution (1.5mg/kg), or olanzapine drinking solution (10mg/kg) for four weeks. Motor and cognitive functions were tested at the end of treatment week 3 and upon drug discontinuation. Two days after drug discontinuation, rats were euthanized and brains were processed for in vitro receptor autoradiography. In chow-fed animals, haloperidol and olanzapine increased CB1R levels in the basal ganglia and the hippocampus, in a similar, but not identical pattern. In addition, olanzapine had unique effects in CB1R upregulation in higher order cognitive areas, in the secondary somatosensory cortex, in the visual and auditory cortices and the geniculate nuclei, as well as in the hypothalamus. High fat food consumption prevented antipsychotic-induced increase in CB1R levels in all regions examined, with one exception, the globus pallidus, in which they were higher in haloperidol-treated rats. The results point towards the hypothesis that increased CB1R levels could be a confounding effect of antipsychotic medication in schizophrenia that is circumveneted by high fat feeding. Copyright © 2017 Elsevier Inc. All rights reserved.

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

    DEFF Research Database (Denmark)

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

    2002-01-01

    -induced excitotoxic damage in the ipsilateral forebrain was not influenced by agonist-stimulated CB receptor function. In contrast, blockade of CB, but not CB, receptor activity evoked a robust neuroprotective response by reducing the infarct area and the number of cortical degenerating neurons. These results suggest...... receptor function on NMDA-induced excitotoxicity. Neonatal (6-day-old) rat pups received a systemic injection of a mixed CB/CB receptor agonist (WIN55,212-2) or their respective antagonists (SR141716A for CB and SR144528 for CB) prior to an unilateral intrastriatal microinjection of NMDA. The NMDA...... a critical involvement of CB receptor tonus on neuronal survival following NMDA receptor-induced excitotoxicity in vivo....

  16. The effect of various opiate receptor agonists on the seizure threshold in the rat. Is dynorphin an endogenous anticonvulsant?

    Science.gov (United States)

    Przewłocka, B; Stala, L; Lasoń, W; Przewłocki, R

    1983-01-01

    The effects of various opiate receptor agonists on the seizure threshold after an intravenous infusion of pentylenetetrazol were investigated in rats. The mu- and epsilon-receptor agonists, morphine (20-40 micrograms) and beta-endorphin (5-10 micrograms) show proconvulsant properties towards clonic and tonic seizures. The delta-receptor agonist (D-Ala2,D-Leu5-enkephalin, DADL 5-40 micrograms) and alpha-neoendorphin (20-40 micrograms) show pro- and anticonvulsant properties towards clonic and tonic seizures, respectively. Anticonvulsant properties of DADL are possibly due to its action on the spinal cord, since after the intrathecal injection this effect is still observed. Similarities between DADL and alpha-neoendorphin suggest that they may act through the same receptor. The kappa-receptor agonist dynorphin A (5-20 micrograms) and its degradation-resistant analogue D-Arg-dynorphin1-13 (10 micrograms) show significant anticonvulsant properties. Our present results suggest that the kappa-receptor agonist dynorphin may act physiologically as an endogenous anticonvulsant, in contrast to other opioid peptides.

  17. Identification of endogenous surrogate ligands for human P2Y12 receptors by in silico and in vitro methods

    International Nuclear Information System (INIS)

    Nonaka, Yosuke; Hiramoto, Takeshi; Fujita, Norihisa

    2005-01-01

    Endogenous ligands acting on a human P2Y 12 receptor, one of the G-protein coupled receptors, were searched by in silico screening against our own database, which contains more than 500 animal metabolites. The in silico screening using the docking software AutoDock resulted in selection of cysteinylleukotrienes (CysLTs) and 5-phosphoribosyl 1-pyrophosphate (PRPP), with high free energy changes, in addition to the known P2Y 12 ligands such as 2MeSADP and ADP. These candidates were subjected to an in vitro Ca 2+ assay using the CHO cells stably expressing P2Y 12 -G 16 α fusion proteins. We found that CysLTE4 and PRPP acted on the P2Y 12 receptor as agonists with the EC 50 values of 1.3 and 7.8 nM, respectively. Furthermore, we analyzed the phylogenetic relationship of the P2Y, P2Y-like, and CysLT receptors based on sequence alignment followed by evolutionary analyses. The analyses showed that the P2Y 12 , P2Y 13 , P2Y 14 , GPR87, CysLT-1, and CysLT-2 receptors formed a P2Y-related receptor subfamily with common sequence motifs in the transmembrane regions

  18. Tumor necrosis factor α sensitizes spinal cord TRPV1 receptors to the endogenous agonist N-oleoyldopamine

    Directory of Open Access Journals (Sweden)

    Spicarova Diana

    2010-08-01

    Full Text Available Abstract Modulation of synaptic transmission in the spinal cord dorsal horn is thought to be involved in the development and maintenance of different pathological pain states. The proinflamatory cytokine, tumor necrosis factor α (TNFα, is an established pain modulator in both the peripheral and the central nervous system. Up-regulation of TNFα and its receptors (TNFR in dorsal root ganglion (DRG cells and in the spinal cord has been shown to play an important role in neuropathic and inflammatory pain conditions. Transient receptor potential vanilloid 1 (TRPV1 receptors are known as molecular integrators of nociceptive stimuli in the periphery, but their role on the spinal endings of nociceptive DRG neurons is unclear. The endogenous TRPV1 receptor agonist N-oleoyldopamine (OLDA was shown previously to activate spinal TRPV1 receptors. In our experiments the possible influence of TNFα on presynaptic spinal cord TRPV1 receptor function was investigated. Using the patch-clamp technique, miniature excitatory postsynaptic currents (mEPSCs were recorded in superficial dorsal horn neurons in acute slices after incubation with 60 nM TNFα. A population of dorsal horn neurons with capsaicin sensitive primary afferent input recorded after the TNFα pretreatment had a basal mEPSC frequency of 1.35 ± 0.20 Hz (n = 13, which was significantly higher when compared to a similar population of neurons in control slices (0.76 ± 0.08 Hz; n = 53; P

  19. Detection of Heteromers Formed by Cannabinoid CB1, Dopamine D2, and Adenosine A2A G-Protein-Coupled Receptors by Combining Bimolecular Fluorescence Complementation and Bioluminescence Energy Transfer

    Science.gov (United States)

    Navarro, Gemma; Carriba, Paulina; Gandí, Jorge; Ciruela, Francisco; Casadó, Vicent; Cortés, Antoni; Mallol, Josefa; Canela, Enric I.; Lluis, Carmen; Franco, Rafael

    2008-01-01

    Functional interactions in signaling occur between dopamine D2 (D2R) and cannabinoid CB1 (CB1R) receptors, between CB1R and adenosine A2A (A2AR) receptors, and between D2R and A2AR. Furthermore, direct molecular interactions have been reported for the pairs CB1R-D2R, A2AR-D2R, and CB1R-A2AR. Here a combination of bimolecular fluorescence complementation and bioluminescence energy transfer techniques was used to identify the occurrence of D2R-CB1R-A2AR hetero-oligomers in living cells. PMID:18956124

  20. Detection of Heteromers Formed by Cannabinoid CB1, Dopamine D2, and Adenosine A2A G-Protein-Coupled Receptors by Combining Bimolecular Fluorescence Complementation and Bioluminescence Energy Transfer

    Directory of Open Access Journals (Sweden)

    Gemma Navarro

    2008-01-01

    Full Text Available Functional interactions in signaling occur between dopamine D2 (D2R and cannabinoid CB1 (CB1R receptors, between CB1R and adenosine A2A (A2AR receptors, and between D2R and A2AR. Furthermore, direct molecular interactions have been reported for the pairs CB1R-D2R, A2AR-D2R, and CB1R-A2AR. Here a combination of bimolecular fluorescence complementation and bioluminescence energy transfer techniques was used to identify the occurrence of D2R-CB1R-A2AR hetero-oligomers in living cells.

  1. Benzodiazepine receptor ligand influences on learning: an endogenous modulatory mechanism mediated by benzodiazepines possibly of alimentary origin

    Directory of Open Access Journals (Sweden)

    I. Izquierdo

    1991-01-01

    Full Text Available In rats pre-but not post-training ip administration of either flumazenil, a central benzodiazepine (BSD receptor antagonist, or of n-butyl-B-carboline-carboxylate (BCCB, an inverse agonist, enhanced retention of inhibitory avoidance learning. Flumazenil vlocked the enhancing effect of BCCB, and the inhibitory effect of the BZD agonists clonazepam and diazepam also given pre-training. Post-training administration of these drugs had no effects. The peripheral BZD receptor agonist/chloride channel blocker Ro5-4864 had no effect on the inhibitory avoidance task when given ip prior to training, buth it caused enhancement when given immediately post-training either ip or icv. This effect was blocked by PK11195, a competitive antagonist of Ro5-4864. These results suggest that ther is an endogenous mechanism mediated by BZD agonists, which is sensitive to inverse agonists and that normally down-regulates the formation of memories through a mechanism involving GABA-A receptors and the corresponding chloride channels. The most likely agonists for the endogenous mechanism suggested are the diazepam-like BZDs found in brain whose origin is possibly alimentary. Levels of these BZDs in the cortex were found to sharply decrease after inhibitory acoidance training or mere exposure to the training apparatus.

  2. Δ8-Tetrahydrocannabinol induces cytotoxicity in macrophage J774-1 cells: Involvement of cannabinoid receptor 2 and p38 MAPK

    International Nuclear Information System (INIS)

    Yamaori, Satoshi; Ishii, Hirosuke; Chiba, Kenzo; Yamamoto, Ikuo; Watanabe, Kazuhito

    2013-01-01

    Tetrahydrocannabinol (THC), a psychoactive component of marijuana, is known to exert cytotoxicity in immune cells. In the present study, we examined the cytotoxicity of Δ 8 -THC in mouse macrophage J774-1 cells and a possible involvement of cannabinoid receptors and stress-responsive mitogen-activated protein kinases (MAPKs) in the cytotoxic process. J774-1 cells were treated with Δ 8 -THC (0–20 μM) for up to 6 h. As measured by the MTT and LDH assays, Δ 8 -THC induced cell death of J774-1 cells in a concentration- and/or exposure time-dependent manner. Δ 8 -THC-induced cell damage was associated with vacuole formation, cell swelling, chromatin condensation, and nuclear fragmentation. The cytotoxic effect of Δ 8 -THC was significantly prevented by a caspase-1 inhibitor Ac-YVAD-cmk but not a caspase-3 inhibitor z-DEVD-fmk. The pretreatment with SR144528, a CB 2 receptor-selective antagonist, effectively suppressed Δ 8 -THC-induced cytotoxicity in J774-1 cells, which exclusively expressed CB 2 receptors as indicated by real-time polymerase chain reaction analysis. In contrast, AM251, a CB 1 receptor-selective antagonist, did not affect the cytotoxicity. Pertussis toxin and α-tocopherol significantly attenuated Δ 8 -THC-induced cytotoxicity suggesting that G i/o protein coupling signal transduction and oxidative stress are responsible for the cytotoxicity. Δ 8 -THC stimulated the phosphorylation of p38 MAPK and c-Jun N-terminal kinase (JNK) in J774-1 cells, which were effectively antagonized by the pretreatment with SR144528. In addition, SB203580, a p38 MARK inhibitor, significantly attenuated the cytotoxic effect of Δ 8 -THC, whereas SP600125, a JNK inhibitor, significantly enhanced the cytotoxicity. These results suggest that the cytotoxicity of Δ 8 -THC to J774-1 cells is exerted mediated through the CB 2 receptor followed by the activation of p38 MAPK

  3. The Pharmacologic and Clinical Effects of Illicit Synthetic Cannabinoids.

    Science.gov (United States)

    White, C Michael

    2017-03-01

    This article presents information on illicitly used synthetic cannabinoids. Synthetic cannabinoids are structurally heterogeneous and commonly used drugs of abuse that act as full agonists of the cannabinoid type-1 receptor but have a variety of additional pharmacologic effects. There are numerous cases of patient harm and death in the United States, Europe, and Australia with many psychological, neurological, cardiovascular, pulmonary, and renal adverse events. Although most users prefer using cannabis, there are convenience, legal, and cost reasons driving the utilization of synthetic cannabinoids. Clinicians should be aware of pharmacologic and clinical similarities and differences between synthetic cannabinoid and cannabis use, the limited ability to detect synthetic cannabinoids in the urine or serum, and guidance to treat adverse events. © 2016, The American College of Clinical Pharmacology.

  4. Demonstration of the dynamic mass redistribution label-free technology as a useful cell-based pharmacological assay for endogenously expressed GABAA receptors

    DEFF Research Database (Denmark)

    Klein, Anders Bue; Nittegaard-Nielsen, Mia; Christensen, Julie T.

    2015-01-01

    the immortalized IMR-32 neuroblastoma cell line, which expresses relatively high levels of several endogenous GABAA receptor subunits, we show that GABA produces concentration-dependent cellular responses that can be measured and quantified in real-time. With the aid of the GABAA receptor-specific agonist muscimol...

  5. Cannabinoid CB1 /CB2 receptor agonists attenuate hyperactivity and body weight loss in a rat model of activity-based anorexia.

    Science.gov (United States)

    Scherma, Maria; Satta, Valentina; Collu, Roberto; Boi, Maria Francesca; Usai, Paolo; Fratta, Walter; Fadda, Paola

    2017-08-01

    Anorexia nervosa (AN) is a serious psychiatric condition characterized by excessive body weight loss and disturbed perceptions of body shape and size, often associated with excessive physical activity. There is currently no effective drug-related therapy of this disease and this leads to high relapse rate. Clinical data suggest that a promising therapy to treat and reduce reoccurrence of AN may be based on the use of drugs that target the endocannabinoid (EC) system, which appears dysregulated in AN patients. The activity-based anorexia (ABA) rodent model mimics the severe body weight loss and increased physical activity, as well as the neuroendocrine disturbances (i.e. hypoleptinaemia and hypercortisolaemia) in AN. This study investigated whether cannabinoid agonists can effectively modify anorexic-like behaviours and neuroendocrine changes in rats subjected to a repeated ABA regime that mimics the human condition in which patients repeatedly undergo a recovery and illness cycle. Our data show that subchronic treatment with both the natural CB 1 /CB 2 receptor agonist Δ 9 -tetrahydrocannabinol and the synthetic CB 1 /CB 2 receptor agonist CP-55,940 significantly reduced body weight loss and running wheel activity in ABA rats. These behavioural effects were accompanied by an increase in leptin signalling and a decrease in plasma levels of corticosterone. Taken together, our results further demonstrate the involvement of the EC system in AN pathophysiology and that strategies which modulate EC signalling are useful to treat this disorder, specifically in patients where physical hyperactivity plays a central role in its progression and maintenance. © 2017 The British Pharmacological Society.

  6. 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)

    Casteels, Cindy; Koole, Michel; Laere, Koen van; Celen, Sofie; Bormans, Guy

    2012-01-01

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

  7. Novel orally available salvinorin A analog PR-38 protects against experimental colitis and reduces abdominal pain in mice by interaction with opioid and cannabinoid receptors.

    Science.gov (United States)

    Sałaga, Maciej; Polepally, Prabhakar Reddy; Zakrzewski, Piotr K; Cygankiewicz, Adam; Sobczak, Marta; Kordek, Radzisław; Zjawiony, Jordan K; Krajewska, Wanda M; Fichna, Jakub

    2014-12-15

    Salvinorin A (SA) is a potent anti-inflammatory diterpene isolated from the Mexican plant S. divinorum. Recently we showed that the novel SA analog, PR-38 has an inhibitory effect on mouse gastrointestinal (GI) motility mediated by opioid and cannabinoid (CB) receptors. The aim of the study was to characterize possible anti-inflammatory and antinociceptive action of PR-38 in the mouse GI tract. Macro- and microscopic colonic damage scores and myeloperoxidase activity were determined after intraperitoneal (i.p.), intracolonic (i.c.), and per os (p.o.) administration of PR-38 in the trinitrobenzene sulfonic acid (TNBS) and dextran sodium sulfate (DSS) models of colitis in mice. Additionally, MOP, KOP and CB1 protein expression was determined using Western blot analysis of mouse colon samples. The antinociceptive effect of PR-38 was examined based on the number of behavioral responses to i.c. instillation of mustard oil (MO). The i.p. (10 mg/kg, twice daily), i.c. (10 mg/kg, twice daily) and p.o. (20 mg/kg, once daily) administration of PR-38 significantly attenuated TNBS- and DSS-induced colitis in mice. The effect of PR-38 was partially blocked by the KOP antagonist nor-binaltorphimine and CB1 antagonist AM 251. Western blot analysis showed a significant increase of MOP, KOP and CB1 receptor expression during colonic inflammation, which was reversed to the control levels by the administration of PR-38. PR-38 significantly decreased the number of pain responses after i.c. instillation of MO in the TNBS-treated mice. Our results suggest that PR-38 has the potential to become a valuable anti-inflammatory and analgesic therapeutic for the treatment of GI inflammation. Copyright © 2014 Elsevier Inc. All rights reserved.

  8. Cannabinoid type 1 receptor ligands WIN 55,212-2 and AM 251 alter anxiety-like behaviors of marmoset monkeys in an open-field test.

    Science.gov (United States)

    Cagni, Priscila; Barros, Marilia

    2013-03-01

    Cannabinoid type 1 receptors (CB1r) are an important modulatory site for emotional behavior. However, little is known on the effects of CB1r ligands on emotionality aspects of primates, even with their highly similar behavioral response and receptor density/distribution as humans. Thus, we analyzed the effects of the CB1r agonist WIN 55,212-2 (WIN; 1mg/kg) and the antagonist AM 251 (AM; 2mg/kg), systemically administered prior to a single brief (15 min) exposure to a novel open-field (OF) environment, on the behavior of individually tested adult black tufted-ear marmosets. Both WIN- and AM-treated subjects, compared to vehicle controls, had significantly lower rates of long (contact) calls and exploration, while higher levels of vigilance-related behaviors (scan/glance); these are indicators of anxiolysis in this setup. Changes in locomotion were not detected. However, in the vehicle and AM-groups, sojourn in the peripheral zone of the OF was significantly higher than in its central region. WIN-treated marmosets spent an equivalent amount of time in both zones. Therefore, activation or blockade CB1r function prior to a short and individual exposure to an unfamiliar environment exerted a significant and complex influence on different behavioral indicators of anxiety in these monkeys (i.e., a partially overlapping anxiolytic-like profile). AM 251, however, has no anxiolytic effect when the time spent in the center of the OF is considered. This is a major difference when compared to the WIN-treated group. Data were compared to the response profile reported in other pre-clinical (rodent) and clinical studies. Copyright © 2012 Elsevier B.V. All rights reserved.

  9. Synthesis, biodistribution and in vitro evaluation of brain permeable high affinity type 2 cannabinoid receptor agonists [11C]MA2 and [18F]MA3

    Directory of Open Access Journals (Sweden)

    Muneer Ahamed

    2016-09-01

    Full Text Available Abstract The type 2 cannabinoid receptor (CB2 is a member of the endocannabinoid system and is known for its important role in (neuroinflammation. A PET-imaging agent that allows in vivo visualization of CB2 expression may thus allow quantification of neuroinflammation. In this paper, we report the synthesis, radiosynthesis, biodistribution and in vitro evaluation of a carbon-11 ([11C]MA2 and a fluorine-18 ([18F]MA3 labeled analogue of a highly potent N-arylamide oxadiazole CB2 agonist (EC50 = 0.015 nM. MA2 and MA3 behaved as potent CB2 agonist (EC50: 3 nM and 0.1 nM, respectively and their in vitro binding affinity for hCB2 was found to be 87 nM and 0.8 nM, respectively. Also MA3 (substituted with a fluoro ethyl group was found to have higher binding affinity and EC50 values when compared to the originally reported trifluoromethyl analogue 12. [11C]MA2 and [18F]MA3 were successfully synthesized with good radiochemical yield, high radiochemical purity and high specific activity. In mice, both tracers were efficiently cleared from blood and all major organs by the hepatobiliary pathway and importantly these compounds showed high brain uptake. In conclusion, [11C]MA2 and [18F]MA3 are shown to be high potent CB2 agonists with good brain uptake, these favorable characteristics makes them potential PET probes for in vivo imaging of brain CB2 receptors. However in view of its higher affinity and selectivity, further detailed evaluation of MA3 as a PET tracer for CB2 is warranted.

  10. Synthesis, Biodistribution and In vitro Evaluation of Brain Permeable High Affinity Type 2 Cannabinoid Receptor Agonists [11C]MA2 and [18F]MA3.

    Science.gov (United States)

    Ahamed, Muneer; van Veghel, Daisy; Ullmer, Christoph; Van Laere, Koen; Verbruggen, Alfons; Bormans, Guy M

    2016-01-01

    The type 2 cannabinoid receptor (CB2) is a member of the endocannabinoid system and is known for its important role in (neuro)inflammation. A PET-imaging agent that allows in vivo visualization of CB2 expression may thus allow quantification of neuroinflammation. In this paper, we report the synthesis, radiosynthesis, biodistribution and in vitro evaluation of a carbon-11 ([ 11 C]MA2) and a fluorine-18 ([ 18 F]MA3) labeled analog of a highly potent N -arylamide oxadiazole CB2 agonist (EC 50 = 0.015 nM). MA2 and MA3 behaved as potent CB2 agonist (EC 50 : 3 nM and 0.1 nM, respectively) and their in vitro binding affinity for h CB2 was found to be 87 nM and 0.8 nM, respectively. Also MA3 (substituted with a fluoro ethyl group) was found to have higher binding affinity and EC 50 values when compared to the originally reported trifluoromethyl analog 12 . [ 11 C]MA2 and [ 18 F]MA3 were successfully synthesized with good radiochemical yield, high radiochemical purity and high specific activity. In mice, both tracers were efficiently cleared from blood and all major organs by the hepatobiliary pathway and importantly these compounds showed high brain uptake. In conclusion, [ 11 C]MA2 and [ 18 F]MA3 are shown to be high potent CB2 agonists with good brain uptake, these favorable characteristics makes them potential PET probes for in vivo imaging of brain CB2 receptors. However, in view of its higher affinity and selectivity, further detailed evaluation of MA3 as a PET tracer for CB2 is warranted.

  11. Endogenous Nur77 Is a Specific Indicator of Antigen Receptor Signaling in Human T and B Cells.

    Science.gov (United States)

    Ashouri, Judith F; Weiss, Arthur

    2017-01-15

    Distinguishing true Ag-stimulated lymphocytes from bystanders activated by the inflammatory milieu has been difficult. Nur77 is an immediate early gene whose expression is rapidly upregulated by TCR signaling in murine T cells and human thymocytes. Nur77-GFP transgenes serve as specific TCR and BCR signaling reporters in murine transgenic models. In this study, we demonstrate that endogenous Nur77 protein expression can serve as a reporter of TCR and BCR specific signaling in human PBMCs. Nur77 protein amounts were assessed by immunofluorescence and flow cytometry in T and B cells isolated from human PBMCs obtained from healthy donors that had been stimulated by their respective Ag receptors. We demonstrate that endogenous Nur77 is a more specific reporter of Ag-specific signaling events than the commonly used CD69 activation marker in both human T and B cells. This is reflective of the disparity in signaling pathways that regulate the expression of Nur77 and CD69. Assessing endogenous Nur77 protein expression has great potential to identify Ag-activated lymphocytes in human disease. Copyright © 2017 by The American Association of Immunologists, Inc.

  12. Endogenous CNS Expression of Neurotensin and Neurotensin Receptors Is Altered during the Postpartum Period in Outbred Mice

    Science.gov (United States)

    Driessen, Terri M.; Zhao, Changjiu; Whittlinger, Anna; Williams, Horecia; Gammie, Stephen C.

    2014-01-01

    Neurotensin (NT) is a neuropeptide identical in mice and humans that is produced and released in many CNS regions associated with maternal behavior. NT has been linked to aspects of maternal care and previous studies have indirectly suggested that endogenous NT signaling is altered in the postpartum period. In the present study, we directly examine whether NT and its receptors exhibit altered gene expression in maternal relative to virgin outbred mice using real time quantitative PCR (qPCR) across multiple brain regions. We also examine NT protein levels using anti-NT antibodies and immunohistochemistry in specific brain regions. In the medial preoptic area (MPOA), which is critical for maternal behaviors, mRNA of NT and NT receptor 3 (Sort1) were significantly up-regulated in postpartum mice compared to virgins. NT mRNA was also elevated in postpartum females in the bed nucleus of the stria terminalis dorsal. However, in the lateral septum, NT mRNA was down-regulated in postpartum females. In the paraventricular nucleus of the hypothalamus (PVN), Ntsr1 expression was down-regulated in postpartum females. Neurotensin receptor 2 (Ntsr2) expression was not altered in any brain region tested. In terms of protein expression, NT immunohistochemistry results indicated that NT labeling was elevated in the postpartum brain in the MPOA, lateral hypothalamus, and two subregions of PVN. Together, these findings indicate that endogenous changes occur in NT and its receptors across multiple brain regions, and these likely support the emergence of some maternal behaviors. PMID:24416154

  13. Cannabinoid exposure during zebra finch sensorimotor vocal learning persistently alters expression of endocannabinoid signaling elements and acute agonist responsiveness

    Directory of Open Access Journals (Sweden)

    Lichtman Aron H

    2011-01-01

    Full Text Available Abstract Background Previously we have found that cannabinoid treatment of zebra finches during sensorimotor stages of vocal development alters song patterns produced in adulthood. Such persistently altered behavior must be attributable to changes in physiological substrates responsible for song. We are currently working to identify the nature of such physiological changes, and to understand how they contribute to altered vocal learning. One possibility is that developmental agonist exposure results in altered expression of elements of endocannabinoid signaling systems. To test this hypothesis we have studied effects of the potent cannabinoid receptor agonist WIN55212-2 (WIN on endocannabinoid levels and densities of CB1 immunostaining in zebra finch brain. Results We found that late postnatal WIN treatment caused a long-term global disregulation of both levels of the endocannabinoid, 2-arachidonyl glycerol (2-AG and densities of CB1 immunostaining across brain regions, while repeated cannabinoid treatment in adults produced few long-term changes in the endogenous cannabinoid system. Conclusions Our findings indicate that the zebra finch endocannabinoid system is particularly sensitive to exogenous agonist exposure during the critical period of song learning and provide insight into susceptible brain areas.

  14. Expression profiles and functional associations of endogenous androgen receptor and caveolin-1 in prostate cancer cell lines.

    Science.gov (United States)

    Bennett, Nigel C; Hooper, John D; Johnson, David W; Gobe, Glenda C

    2014-05-01

    In prostate cancer (PCa) patients, the protein target for androgen deprivation and blockade therapies is androgen receptor (AR). AR interacts with many proteins that function to either co-activate or co-repress its activity. Caveolin-1 (Cav-1) is not found in normal prostatic epithelium, but is found in PCa, and may be an AR co-regulator protein. We investigated cell line-specific signatures and associations of endogenous AR and Cav-1 in six PCa cell lines of known androgen sensitivity: LNCaP (androgen sensitive); 22Rv1 (androgen responsive); PC3, DU145, and ALVA41 (androgen non-reliant); and RWPE1 (non-malignant). Protein and mRNA expression profiles were compared and electron microscopy used to identify cells with caveolar structures. For cell lines expressing both AR and Cav-1, knockdown techniques using small interfering RNA against AR or Cav-1 were used to test whether diminished expression of one affected the other. Co-sedimentation of AR and Cav-1 was used to test their association. A reporter assay for AR genomic activity was utilized following Cav-1 knockdown. AR-expressing LNCaP and 22Rv1 cells had low endogenous Cav-1 mRNA and protein. Cell lines that expressed little or no AR (DU145, PC3, ALVA41, and RWPE1) expressed high endogenous levels of Cav-1. AR knockdown in LNCaP cells had little effect on Cav-1, but Cav-1 knockdown inhibited AR expression and genomic activity. These data show endogenous AR and Cav-1 mRNA and protein expression is inversely related in PCa cells, with Cav-1 acting on the androgen/AR signaling axis possibly as an AR co-activator, demonstrated by diminished AR genomic activity following Cav-1 knockdown. © 2013 Wiley Periodicals, Inc.

  15. 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

    not significantly different. Conclusions: Although changes in CB1 receptor expression have been demonstrated in human suicide victims with depression and in animal models of depression, the present maps of [3H]OMAR binding revealed no difference between FSL and FRL rats. We used a single concentration of [3H......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...

  16. Facilitation of acetylcholine release in rat frontal cortex by indeloxazine hydrochloride: involvement of endogenous serotonin and 5-HT4 receptors.

    Science.gov (United States)

    Yamaguchi, T; Suzuki, M; Yamamoto, M

    1997-12-01

    Effects of indeloxazine hydrochloride, an inhibitor of serotonin (5-HT) and norepinephrine (NE) reuptake with a facilitatory effect on 5-HT release, on acetylcholine (ACh) output in frontal cortex of conscious rats were characterized using an in vivo microdialysis technique. Systemic administration of indeloxazine (3 and 10 mg/kg, i.p.) increased ACh and 5-HT output in a dose-dependent manner. Depletion of endogenous monoamines by reserpine and of 5-HT by p-chlorophenylalanine, but not that of catecholamines by alpha-methyl-p-tyrosine, significantly attenuated the facilitatory effect of indeloxazine on ACh release. When applied locally by reverse dialysis, indeloxazine (10 and 30 microM) and the selective 5-HT reuptake inhibitor citalopram (10 microM), but not the NE reuptake inhibitor maprotiline (30 microM), increased cortical ACh output. Indeloxazine (10 mg/kg)-induced increase in ACh release was significantly inhibited by local application of the 5-HT4 receptor antagonists RS23597 (50 microM) and GR113803 (1 microM), while the 5-HT1A antagonist WAY-100135 (100 microM), 5-HT1A/1B/beta-adrenoceptor antagonist (-)propranolol (150 microM), 5-HT2A/2C antagonist ritanserin (10 microM) and 5-HT3 antagonist ondansetron (10 microM) failed to significantly modify this effect. Neither depletion of monoamines nor treatment with serotonergic antagonists significantly changed the basal ACh level, indicating that endogenous monoamines do not tonically activate ACh release. These results suggest that indeloxazine-induced facilitation of ACh release in rat frontal cortex is mediated by endogenous 5-HT and involves at least in part cortical 5-HT4 receptors.

  17. Ligand-independent Thrombopoietin Mutant Receptor Requires Cell Surface Localization for Endogenous Activity*

    OpenAIRE

    Marty, Caroline; Chaligné, Ronan; Lacout, Catherine; Constantinescu, Stefan N.; Vainchenker, William; Villeval, Jean-Luc

    2009-01-01

    The activating W515L mutation in the thrombopoietin receptor (MPL) has been identified in primary myelofibrosis and essential thrombocythemia. MPL belongs to a subset of the cytokine receptor superfamily that requires the JAK2 kinase for signaling. We examined whether the ligand-independent MPLW515L mutant could signal intracellularly. Addition of the endoplasmic reticulum (ER) retention KDEL sequence to the receptor C terminus efficiently locked MPLW515L within its na...

  18. Targeting Cannabinoid Signaling in the Immune System: “High”-ly Exciting Questions, Possibilities, and Challenges

    Directory of Open Access Journals (Sweden)

    Attila Oláh

    2017-11-01

    Full Text Available It is well known that certain active ingredients of the plants of Cannabis genus, i.e., the “phytocannabinoids” [pCBs; e.g., (−-trans-Δ9-tetrahydrocannabinol (THC, (−-cannabidiol, etc.] can influence a wide array of biological processes, and the human body is able to produce endogenous analogs of these substances [“endocannabinoids” (eCB, e.g., arachidonoylethanolamine (anandamide, AEA, 2-arachidonoylglycerol (2-AG, etc.]. These ligands, together with multiple receptors (e.g., CB1 and CB2 cannabinoid receptors, etc., and a complex enzyme and transporter apparatus involved in the synthesis and degradation of the ligands constitute the endocannabinoid system (ECS, a recently emerging regulator of several physiological processes. The ECS is widely expressed in the human body, including several members of the innate and adaptive immune system, where eCBs, as well as several pCBs were shown to deeply influence immune functions thereby regulating inflammation, autoimmunity, antitumor, as well as antipathogen immune responses, etc. Based on this knowledge, many in vitro and in vivo studies aimed at exploiting the putative therapeutic potential of cannabinoid signaling in inflammation-accompanied diseases (e.g., multiple sclerosis or in organ transplantation, and to dissect the complex immunological effects of medical and “recreational” marijuana consumption. Thus, the objective of the current article is (i to summarize the most recent findings of the field; (ii to highlight the putative therapeutic potential of targeting cannabinoid signaling; (iii to identify open questions and key challenges; and (iv to suggest promising future directions for cannabinoid-based drug development.

  19. Plasticity of Signaling by Spinal Estrogen Receptor α, κ-Opioid Receptor, and Metabotropic Glutamate Receptors over the Rat Reproductive Cycle Regulates Spinal Endomorphin 2 Antinociception: Relevance of Endogenous-Biased Agonism.

    Science.gov (United States)

    Liu, Nai-Jiang; Murugaiyan, Vijaya; Storman, Emiliya M; Schnell, Stephen A; Kumar, Arjun; Wessendorf, Martin W; Gintzler, Alan R

    2017-11-15

    We previously showed that intrathecal application of endomorphin 2 [EM2; the highly specific endogenous μ-opioid receptor (MOR) ligand] induces antinociception that varies with stage of the rat estrous cycle: minimal during diestrus and prominent during proestrus. Earlier studies, however, did not identify proestrus-activated signaling strategies that enable spinal EM2 antinociception. We now report that in female rats, increased spinal dynorphin release and κ-opioid receptor (KOR) signaling, as well as the emergence of glutamate-activated metabotropic glutamate receptor 1 (mGluR 1 ) signaling, are critical to the transition from an EM2 nonresponsive state (during diestrus) to an analgesically responsive state (during proestrus). Differential signaling by mGluR 1 , depending on its activation by membrane estrogen receptor α (mERα; during diestrus) versus glutamate (during proestrus), concomitant with the ebb and flow of spinal dynorphin/KOR signaling, functions as a switch, preventing or promoting, respectively, spinal EM2 antinociception. Importantly, EM2 and glutamate-containing varicosities appose spinal neurons that express MOR along with mGluRs and mERα, suggesting that signaling mechanisms regulating analgesic effectiveness of intrathecally applied EM2 also pertain to endogenous EM2. Regulation of spinal EM2 antinociception by both the nature of the endogenous mGluR 1 activator (i.e., endogenous biased agonism at mGluR 1 ) and changes in spinal dynorphin/KOR signaling represent a novel mechanism for modulating analgesic responsiveness to endogenous EM2 (and perhaps other opioids). This points the way for developing noncanonical pharmacological approaches to pain management by harnessing endogenous opioids for pain relief. SIGNIFICANCE STATEMENT The current prescription opioid abuse epidemic underscores the urgency to develop alternative pharmacotherapies for managing pain. We find that the magnitude of spinal endomorphin 2 (EM2) antinociception not only

  20. Abnormalities in Dynamic Brain Activity Caused by Mild Traumatic Brain Injury Are Partially Rescued by the Cannabinoid Type-2 Receptor Inverse Agonist SMM-189.

    Science.gov (United States)

    Liu, Yu; McAfee, Samuel S; Guley, Natalie M; Del Mar, Nobel; Bu, Wei; Heldt, Scott A; Honig, Marcia G; Moore, Bob M; Reiner, Anton; Heck, Detlef H

    2017-01-01

    Mild traumatic brain injury (mTBI) can cause severe long-term cognitive and emotional deficits, including impaired memory, depression, and persevering fear, but the neuropathological basis of these deficits is uncertain. As medial prefrontal cortex (mPFC) and hippocampus play important roles in memory and emotion, we used multi-site, multi-electrode recordings of oscillatory neuronal activity in local field potentials (LFPs) in awake, head-fixed mice to determine if the functioning of these regions was abnormal after mTBI, using a closed-skull focal cranial blast model. We evaluated mPFC, hippocampus CA1, and primary somatosensory/visual cortical areas (S1/V1). Although mTBI did not alter the power of oscillations, it did cause increased coherence of θ (4-10 Hz) and β (10-30 Hz) oscillations within mPFC and S1/V1, reduced CA1 sharp-wave ripple (SWR)-evoked LFP activity in mPFC, downshifted SWR frequencies in CA1, and enhanced θ-γ phase-amplitude coupling (PAC) within mPFC. These abnormalities might be linked to the impaired memory, depression, and persevering fear seen after mTBI. Treatment with the cannabinoid type-2 (CB2) receptor inverse agonist SMM-189 has been shown to mitigate functional deficits and neuronal injury after mTBI in mice. We found that SMM-189 also reversed most of the observed neurophysiological abnormalities. This neurophysiological rescue is likely to stem from the previously reported reduction in neuron loss and/or the preservation of neuronal function and connectivity resulting from SMM-189 treatment, which appears to stem from the biasing of microglia from the proinflammatory M1 state to the prohealing M2 state by SMM-189.

  1. Cannabinoid-1 receptor (CB1R) blockers as medicines: beyond obesity and cardiometabolic disorders to substance abuse/drug addiction with CB1R neutral antagonists.

    Science.gov (United States)

    Janero, David R

    2012-03-01

    Addiction to chemical substances with abuse potential presents medical needs largely unsolved by extant therapeutic strategies. Signal transmission through the cannabinoid-1 receptor (CB1R) in the central nervous system (CNS) modulates neurotransmitters/neuronal pathways contributing to the rewarding properties and hedonic effects of certain nondrug stimuli (e.g., food) and many prototypical addictive drugs, promoting excessive intake and its pathological consequences. Typical CB1R antagonists/inverse agonists reduce the rewarding effects and normalize behavioral phenotypes associated with food and abused drugs, but carry an unacceptable adverse-event profile that may reflect, at least partly, their intrinsic ability to alter basal homeostatic CB1R signaling in the CNS and elicit a negative efficacy response. Alternatively, peripherally biased CB1R inverse agonists with limited CNS permeability and putative CB1R neutral antagonists expressing modest (if any) inverse-agonist efficacy are garnering attention for treating obesity and related cardiometabolic complications with a potentially enhanced benefit-to-risk profile. This mini-review calls attention to the proposition that CB1R neutral antagonists offer attractive opportunities for pharmacotherapeutic exploitation in the substance abuse/drug addiction space, whereas the restricted CNS accessibility of peripherally biased CB1R inverse agonists circumscribes their therapeutic utility for this indication. The unique preclinical pharmacology, efficacy profiles, and reduced adverse-event risk of CB1R neutral antagonists make them worthy of translational study for their potential therapeutic application beyond obesity/cardiometabolic disease to include substance-abuse/drug-addiction disorders.

  2. Temporal changes of CB1 cannabinoid receptor in the basal ganglia as a possible structure-specific plasticity process in 6-OHDA lesioned rats.

    Directory of Open Access Journals (Sweden)

    Gabriela P Chaves-Kirsten

    Full Text Available The endocannabinoid system has been implicated in several neurobiological processes, including neurodegeneration, neuroprotection and neuronal plasticity. The CB1 cannabinoid receptors are abundantly expressed in the basal ganglia, the circuitry that is mostly affected in Parkinson's Disease (PD. Some studies show variation of CB1 expression in basal ganglia in different animal models of PD, however the results are quite controversial, due to the differences in the procedures employed to induce the parkinsonism and the periods analyzed after the lesion. The present study evaluated the CB1 expression in four basal ganglia structures, namely striatum, external globus pallidus (EGP, internal globus pallidus (IGP and substantia nigra pars reticulata (SNpr of rats 1, 5, 10, 20, and 60 days after unilateral intrastriatal 6-hydroxydopamine injections, that causes retrograde dopaminergic degeneration. We also investigated tyrosine hydroxylase (TH, parvalbumin, calbindin and glutamic acid decarboxylase (GAD expression to verify the status of dopaminergic and GABAergic systems. We observed a structure-specific modulation of CB1 expression at different periods after lesions. In general, there were no changes in the striatum, decreased CB1 in IGP and SNpr and increased CB1 in EGP, but this increase was not sustained over time. No changes in GAD and parvalbumin expression were observed in basal ganglia, whereas TH levels were decreased and the calbindin increased in striatum in short periods after lesion. We believe that the structure-specific variation of CB1 in basal ganglia in the 6-hydroxydopamine PD model could be related to a compensatory process involving the GABAergic transmission, which is impaired due to the lack of dopamine. Our data, therefore, suggest that the changes of CB1 and calbindin expression may represent a plasticity process in this PD model.

  3. Novel Peripherally Restricted Cannabinoid 1 Receptor Selective Antagonist TXX-522 with Prominent Weight-Loss Efficacy in Diet Induced Obese Mice

    Directory of Open Access Journals (Sweden)

    Wei Chen

    2017-10-01

    Full Text Available The clinical development of the first generation of globally active cannabinoid 1 receptor (CB1R antagonists was suspended because of their adverse neuropsychiatric effects. Selective blockade of peripheral CB1Rs has the potential to provide a viable strategy for the treatment of severe obesity while avoiding these central nervous system side effects. In the current study, a novel compound (TXX-522 was rationally designed based on the parent nucleus of a classical CB1R-selective antagonist/inverse agonist, rimonabant (SR141716A. Docking assays indicate that TXX-522 was bound with the CB1R in a mode similar to that of SR141716A. TXX-522 showed good binding, CB1R-selectivity (over the CB2R, and functional antagonist activities in a range of in vitro molecular and cellular assays. In vivo analysis of the steady state distribution of TXX-522 in the rat brain and blood tissues and the assay of its functional effects on CB1R activity collectively showed that TXX-522 showed minimal brain penetration. Moreover, the in vivo pharmacodynamic study further revealed that TXX-522 had good oral bioavailability and a potent anti-obesity effect, and ameliorated insulin resistance in high-fat diet-induced obese mice. No impact on food intake was observed in this model, confirming the limited brain penetration of this compound. Thus, the current study indicates that TXX-522 is a novel and potent peripherally acting selective CB1R antagonist with the potential to control obesity and related metabolic disorders.

  4. The endogenous opioid system: a common substrate in drug addiction.

    Science.gov (United States)

    Trigo, José Manuel; Martin-García, Elena; Berrendero, Fernando; Robledo, Patricia; Maldonado, Rafael

    2010-05-01

    Drug addiction is a chronic brain disorder leading to complex adaptive changes within the brain reward circuits that involve several neurotransmitters. One of the neurochemical systems that plays a pivotal role in different aspects of addiction is the endogenous opioid system (EOS). Opioid receptors and endogenous opioid peptides are largely distributed in the mesolimbic system and modulate dopaminergic activity within these reward circuits. Chronic exposure to the different prototypical drugs of abuse, including opioids, alcohol, nicotine, psychostimulants and cannabinoids has been reported to produce significant alterations within the EOS, which seem to play an important role in the development of the addictive process. In this review, we will describe the adaptive changes produced by different drugs of abuse on the EOS, and the current knowledge about the contribution of each component of this neurobiological system to their addictive properties.

  5. Evidence that central pathways that mediate defecation utilize ghrelin receptors but do not require endogenous ghrelin.

    Science.gov (United States)

    Pustovit, Ruslan V; Callaghan, Brid; Ringuet, Mitchell T; Kerr, Nicole F; Hunne, Billie; Smyth, Ian M; Pietra, Claudio; Furness, John B

    2017-08-01

    In laboratory animals and in human, centrally penetrant ghrelin receptor agonists, given systemically or orally, cause defecation. Animal studies show that the effect is due to activation of ghrelin receptors in the spinal lumbosacral defecation centers. However, it is not known whether there is a physiological role of ghrelin or the ghrelin receptor in the control of defecation. Using immunohistochemistry and immunoassay, we detected and measured ghrelin in the stomach, but were unable to detect ghrelin by either method in the lumbosacral spinal cord, or other regions of the CNS In rats in which the thoracic spinal cord was transected 5 weeks before, the effects of a ghrelin agonist on colorectal propulsion were significantly enhanced, but defecation caused by water avoidance stress (WAS) was reduced. In knockout rats that expressed no ghrelin and in wild-type rats, WAS-induced defecation was reduced by a ghrelin receptor antagonist, to similar extents. We conclude that the ghrelin receptors of the lumbosacral defecation centers have a physiological role in the control of defecation, but that their role is not dependent on ghrelin. This implies that a transmitter other than ghrelin engages the ghrelin receptor or a ghrelin receptor complex. © 2017 The Authors. Physiological Reports published by Wiley Periodicals, Inc. on behalf of The Physiological Society and the American Physiological Society.

  6. Cardiovascular effects of marijuana and synthetic cannabinoids: the good, the bad, and the ugly.

    Science.gov (United States)

    Pacher, Pal; Steffens, Sabine; Haskó, György; Schindler, Thomas H; Kunos, George

    2018-03-01

    Dysregulation of the endogenous lipid mediators endocannabinoids and their G-protein-coupled cannabinoid receptors 1 and 2 (CB 1 R and CB 2 R) has been implicated in a variety of cardiovascular pathologies. Activation of CB 1 R facilitates the development of cardiometabolic disease, whereas activation of CB 2 R (expressed primarily in immune cells) exerts anti-inflammatory effects. The psychoactive constituent of marijuana, Δ 9 -tetrahydrocannabinol (THC), is an agonist of both CB 1 R and CB 2 R, and exerts its psychoactive and adverse cardiovascular effects through the activation of CB 1 R in the central nervous and cardiovascular systems. The past decade has seen a nearly tenfold increase in the THC content of marijuana as well as the increased availability of highly potent synthetic cannabinoids for recreational use. These changes have been accompanied by the emergence of serious adverse cardiovascular events, including myocardial infarction, cardiomyopathy, arrhythmias, stroke, and cardiac arrest. In this Review, we summarize the role of the endocannabinoid system in cardiovascular disease, and critically discuss the cardiovascular consequences of marijuana and synthetic cannabinoid use. With the legalization of marijuana for medicinal purposes and/or recreational use in many countries, physicians should be alert to the possibility that the use of marijuana or its potent synthetic analogues might be the underlying cause of severe cardiovascular events and pathologies.

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

    Energy Technology Data Exchange (ETDEWEB)

    Casteels, Cindy [K.U. Leuven, University Hospital Leuven, Division of Nuclear Medicine, Leuven (Belgium); K.U. Leuven, MoSAIC, Molecular Small Animal Imaging Center, Leuven (Belgium); University Hospital Gasthuisberg, Division of Nuclear Medicine, Leuven (Belgium); Koole, Michel; Laere, Koen van [K.U. Leuven, University Hospital Leuven, Division of Nuclear Medicine, Leuven (Belgium); K.U. Leuven, MoSAIC, Molecular Small Animal Imaging Center, Leuven (Belgium); Celen, Sofie; Bormans, Guy [K.U. Leuven, MoSAIC, Molecular Small Animal Imaging Center, Leuven (Belgium); K.U. Leuven, Laboratory for Radiopharmacy, Leuven (Belgium)

    2012-09-15

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

  8. Enhanced novelty-induced corticosterone spike and upregulated serotonin 5-HT1A and cannabinoid CB1 receptors in adolescent BTBR mice.

    Science.gov (United States)

    Gould, Georgianna G; Burke, Teresa F; Osorio, Miguel D; Smolik, Corey M; Zhang, Wynne Q; Onaivi, Emmanuel S; Gu, Ting-Ting; DeSilva, Mauris N; Hensler, Julie G

    2014-01-01

    Hypothalamic pituitary adrenal (HPA) axis responses to change and social challenges during adolescence can influence mental health and behavior into adulthood. To examine how HPA tone in adolescence may contribute to psychopathology, we challenged male adolescent (5 weeks) and adult (16 weeks) BTBR T(+)tf/J (BTBR) and 129S1/SvImJ (129S) mice with novelty in sociability tests. In prior studies these strains had exaggerated or altered HPA stress responses and low sociability relative to C57BL/6J mice in adulthood. In adolescence these strains already exhibited similar or worse sociability deficits than adults or age-matched C57 mice. Yet BTBR adolescents were less hyperactive and buried fewer marbles than adults. Novelty-induced corticosterone (CORT) spikes in adolescent BTBR were double adult levels, and higher than 129S or C57 mice at either age. Due to their established role in HPA feedback, we hypothesized that hippocampal Gαi/o-coupled serotonin 5-HT1A and cannabinoid CB1 receptor function might be upregulated in BTBR mice. Adolescent BTBR mice had higher hippocampal 5-HT1A density as measured by [(3)H] 8-hydroxy-2-(di-n-propylamino) tetralin (8-OH-DPAT) binding than C57 mice, and adult BTBR 8-OH-DPAT-stimulated GTPγS binding was higher than in either C57 or 129S mice in this region. Further, BTBR hippocampal CB1 density measured by [(3)H]CP55,940 binding was 15-20% higher than in C57. CP55,940-stimulated GTPγS binding in adult BTBR dentate gyrus was 30% higher then 129S (p<0.05), but was not a product of greater neuronal or cell density defined by NeuN and DAPI staining. Hence hyperactive HPA responsiveness during adolescence may underlie 5-HT1A and CB1 receptor up-regulation and behavioral phenotype of BTBR mice. Copyright © 2013 Elsevier Ltd. All rights reserved.

  9. Label-Free Proteomic Identification of Endogenous, Insulin-Stimulated Interaction Partners of Insulin Receptor Substrate-1

    Science.gov (United States)

    Geetha, Thangiah; Langlais, Paul; Luo, Moulun; Mapes, Rebekka; Lefort, Natalie; Chen, Shu-Chuan; Mandarino, Lawrence J.; Yi, Zhengping

    2011-03-01

    Protein-protein interactions are key to most cellular processes. Tandem mass spectrometry (MS/MS)-based proteomics combined with co-immunoprecipitation (CO-IP) has emerged as a powerful approach for studying protein complexes. However, a majority of systematic proteomics studies on protein-protein interactions involve the use of protein overexpression and/or epitope-tagged bait proteins, which might affect binding stoichiometry and lead to higher false positives. Here, we report an application of a straightforward, label-free CO-IP-MS/MS method, without the use of protein overexpression or protein tags, to the investigation of changes in the abundance of endogenous proteins associated with a bait protein, which is in this case insulin receptor substrate-1 (IRS-1), under basal and insulin stimulated conditions. IRS-1 plays a central role in the insulin signaling cascade. Defects in the protein-protein interactions involving IRS-1 may lead to the development of insulin resistance and type 2 diabetes. HPLC-ESI-MS/MS analyses identified eleven novel endogenous insulin-stimulated IRS-1 interaction partners in L6 myotubes reproducibly, including proteins play an important role in protein dephosphorylation [protein phosphatase 1 regulatory subunit 12A, (PPP1R12A)], muscle contraction and actin cytoskeleton rearrangement, endoplasmic reticulum stress, and protein folding, as well as protein synthesis. This novel application of label-free CO-IP-MS/MS quantification to assess endogenous interaction partners of a specific protein will prove useful for understanding how various cell stimuli regulate insulin signal transduction.

  10. Identification of cinnabarinic acid as a novel endogenous aryl hydrocarbon receptor ligand that drives IL-22 production.

    Directory of Open Access Journals (Sweden)

    Margaret M Lowe

    Full Text Available The aryl hydrocarbon receptor (AHR binds to environmental toxicants including synthetic halogenated aromatic hydrocarbons and is involved in a diverse array of biological processes. Recently, the AHR was shown to control host immunity by affecting the balance between inflammatory T cells that produce IL-17 (Th17 and IL-22 versus regulatory T cells (Treg involved in tolerance. While environmental AHR ligands can mediate this effect, endogenous ligands are likely to be more relevant in host immune responses. We investigated downstream metabolites of tryptophan as potential AHR ligands because (1 tryptophan metabolites have been implicated in regulating the balance between Th17 and Treg cells and (2 many of the AHR ligands identified thus far are derivatives of tryptophan. We characterized the ability of tryptophan metabolites to bind and activate the AHR and to increase IL-22 production in human T cells. We report that the tryptophan metabolite, cinnabarinic acid (CA, is an AHR ligand that stimulates the differentiation of human and mouse T cells producing IL-22. We compare the IL-22-stimulating activity of CA to that of other tryptophan metabolites and define stimulation conditions that lead to CA production from immune cells. Our findings link tryptophan metabolism to AHR activation and define a novel endogenous AHR agonist with potentially broad biological functions.

  11. Identification of cinnabarinic acid as a novel endogenous aryl hydrocarbon receptor ligand that drives IL-22 production.

    Science.gov (United States)

    Lowe, Margaret M; Mold, Jeff E; Kanwar, Bittoo; Huang, Yong; Louie, Alexander; Pollastri, Michael P; Wang, Cuihua; Patel, Gautam; Franks, Diana G; Schlezinger, Jennifer; Sherr, David H; Silverstone, Allen E; Hahn, Mark E; McCune, Joseph M

    2014-01-01

    The aryl hydrocarbon receptor (AHR) binds to environmental toxicants including synthetic halogenated aromatic hydrocarbons and is involved in a diverse array of biological processes. Recently, the AHR was shown to control host immunity by affecting the balance between inflammatory T cells that produce IL-17 (Th17) and IL-22 versus regulatory T cells (Treg) involved in tolerance. While environmental AHR ligands can mediate this effect, endogenous ligands are likely to be more relevant in host immune responses. We investigated downstream metabolites of tryptophan as potential AHR ligands because (1) tryptophan metabolites have been implicated in regulating the balance between Th17 and Treg cells and (2) many of the AHR ligands identified thus far are derivatives of tryptophan. We characterized the ability of tryptophan metabolites to bind and activate the AHR and to increase IL-22 production in human T cells. We report that the tryptophan metabolite, cinnabarinic acid (CA), is an AHR ligand that stimulates the differentiation of human and mouse T cells producing IL-22. We compare the IL-22-stimulating activity of CA to that of other tryptophan metabolites and define stimulation conditions that lead to CA production from immune cells. Our findings link tryptophan metabolism to AHR activation and define a novel endogenous AHR agonist with potentially broad biological functions.

  12. Kynurenine 3-monooxygenase mediates inhibition of Th17 differentiation via catabolism of endogenous aryl hydrocarbon receptor ligands.

    Science.gov (United States)

    Stephens, Geoffrey L; Wang, Qun; Swerdlow, Bonnie; Bhat, Geetha; Kolbeck, Roland; Fung, Michael

    2013-07-01

    The aryl hydrocarbon receptor (AhR) is a key transcriptional regulator of Th17-cell differentiation. Although endogenous ligands have yet to be identified, evidence suggests that tryptophan metabolites can act as agonists for the AhR. Tryptophan metabolites are abundant in circulation, so we hypothesized that cell intrinsic factors might exist to regulate the exposure of Th17 cells to AhR-dependent activities. Here, we find that Th17 cells preferentially express kynurenine 3-monooxygenase (KMO), which is an enzyme involved in catabolism of the tryptophan metabolite kynurenine. KMO inhibition, either with a specific inhibitor or via siRNA-mediated silencing, markedly increased IL-17 production in vitro, whereas IFN-γ production by Th1 cells was unaffected. Inhibition of KMO significantly exacerbated disease in a Th17-driven model of autoimmune gastritis, suggesting that expression of KMO by Th17 cells serves to limit their continuous exposure to physiological levels of endogenous AhR ligands in vivo. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  13. Cannabinoids as modulators of cancer cell viability, neuronal differentiation, and embryonal development

    OpenAIRE

    Gustafsson, Sofia

    2012-01-01

    Cannabinoids (CBs) are compounds that activate the CB1 and CB2 receptors. CB receptors mediate many different physiological functions, and cannabinoids have been reported to decrease tumor cell viability, proliferation, migration, as well as to modulate metastasis. In this thesis, the effects of cannabinoids on human colorectal carcinoma Caco-2 cells (Paper I) and mouse P19 embryonal carcinoma (EC) cells (Paper III) were studied.  In both cell lines, the compounds examined produced a concentr...

  14. Ligand-independent Thrombopoietin Mutant Receptor Requires Cell Surface Localization for Endogenous Activity*

    Science.gov (United States)

    Marty, Caroline; Chaligné, Ronan; Lacout, Catherine; Constantinescu, Stefan N.; Vainchenker, William; Villeval, Jean-Luc

    2009-01-01

    The activating W515L mutation in the thrombopoietin receptor (MPL) has been identified in primary myelofibrosis and essential thrombocythemia. MPL belongs to a subset of the cytokine receptor superfamily that requires the JAK2 kinase for signaling. We examined whether the ligand-independent MPLW515L mutant could signal intracellularly. Addition of the endoplasmic reticulum (ER) retention KDEL sequence to the receptor C terminus efficiently locked MPLW515L within its natural ER/Golgi maturation pathway. In contrast to cells expressing the parental MPLW515L, MPLW515L-KDEL-expressing FDC-P1 cells were unable to grow autonomously and to produce tumors in nude mice. When observed, tumor nodules resulted from in vivo selection of cells leaking the receptor at their surface. JAK2 co-immunoprecipitated with MPLW515L-KDEL but was not phosphorylated. We generated disulfide-bonded MPLW515L homodimers by the S402C substitution, both in the normal and KDEL context. Unlike MPLW515L-KDEL, MPLW515L-S402C-KDEL signaled constitutively and exhibited cell surface localization. These data establish that MPLW515L with appended JAK2 matures through the ER/Golgi system in an inactive conformation and suggest that the MPLW515L/JAK2 complex requires membrane localization for JAK2 phosphorylation, resulting in autonomous receptor signaling. PMID:19261614

  15. Identification of endogenous opioid receptor components in rat brain using a monoclonal antibody

    Energy Technology Data Exchange (ETDEWEB)

    Bero, L.A.; Roy, S.; Lee, N.M.

    1988-11-01

    A monoclonal antibody generated against the tertiary structure of a partially purified opioid binding protein was used to probe the structure of the dynorphin and beta-endorphin receptors. The Fab fragment 3B4F11 inhibited completely the binding of 125I-beta-endorphin and (3H)dynorphin to rat brain P2 membranes with IC50 values of 26 ng/ml and 40 ng/ml, respectively. To explore further the interaction of 3B4F11 with the beta-endorphin receptor, the effect of the Fab fragment on 125I-beta-endorphin cross-linking to rat brain membranes was examined. 125I-beta-endorphin was covalently bound to three major species of approximate molecular weights 108,000, 73,000, and 49,000. The delta-selective ligand D-Pen2, D-pen5enkephalin was least effective at inhibiting the cross-linking of beta-endorphin, whereas the micro-selective ligand Tyr-D-Ala-Gly-NMe-Phe-Gly-ol and kappa-selective ligand U50488 inhibited beta-endorphin cross-linking to the 108,000 and 73,000 Da species. Both 3B4F11 and beta-endorphin prevented the covalent binding of 125I-beta-endorphin to all three labeled species. These findings suggest that micro and kappa receptor types might have some structural similarities, whereas the delta receptor type might differ in molecular size. In addition, the micro, kappa, and delta ligands might have different primary sequences, whereas their tertiary structures might share regions of molecular homology with all three receptor constituents labeled by 125I-beta-endorphin. 3B4F11 will be a valuable tool for the purification and isolation of the several components of the beta-endorphin receptor complex.

  16. Cell-specific STORM superresolution imaging reveals nanoscale organization of cannabinoid signaling

    Science.gov (United States)

    Szabó, Szilárd I.; Szabadits, Eszter; Pintér, Balázs; Woodhams, Stephen G.; Henstridge, Christopher M.; Balla, Gyula Y.; Nyilas, Rita; Varga, Csaba; Lee, Sang-Hun; Matolcsi, Máté; Cervenak, Judit; Kacskovics, Imre; Watanabe, Masahiko; Sagheddu, Claudia; Melis, Miriam; Pistis, Marco; Soltesz, Ivan; Katona, István

    2014-01-01

    A major challenge in neuroscience is to determine the nanoscale position and quantity of signaling molecules in a cell-type-, and subcellular compartment-specific manner. We therefore developed a novel approach combining cell-specific physiological and anatomical characterization with superresolution imaging, and studied the molecular and structural parameters shaping the physiological properties of synaptic endocannabinoid signaling in the mouse hippocampus. We found that axon terminals of perisomatically-projecting GABAergic interneurons possess increased CB1 receptor number, active-zone complexity, and receptor/effector ratio compared to dendritically-projecting interneurons, in agreement with higher efficiency of cannabinoid signaling at somatic versus dendritic synapses. Furthermore, chronic Δ9-tetrahydrocannabinol administration, which reduces cannabinoid efficacy on GABA release, evoked dramatic CB1-downregulation in a dose-dependent manner. Full receptor recovery required several weeks after cessation of Δ9-tetrahydrocannabinol treatment. These findings demonstrate that cell-type-specific nanoscale analysis of endogenous protein distribution is possible in brain circuits, and identify novel molecular properties controlling endocannabinoid signaling and cannabis-induced cognitive dysfunction. PMID:25485758

  17. Cell-specific STORM super-resolution imaging reveals nanoscale organization of cannabinoid signaling.

    Science.gov (United States)

    Dudok, Barna; Barna, László; Ledri, Marco; Szabó, Szilárd I; Szabadits, Eszter; Pintér, Balázs; Woodhams, Stephen G; Henstridge, Christopher M; Balla, Gyula Y; Nyilas, Rita; Varga, Csaba; Lee, Sang-Hun; Matolcsi, Máté; Cervenak, Judit; Kacskovics, Imre; Watanabe, Masahiko; Sagheddu, Claudia; Melis, Miriam; Pistis, Marco; Soltesz, Ivan; Katona, István

    2015-01-01

    A major challenge in neuroscience is to determine the nanoscale position and quantity of signaling molecules in a cell type- and subcellular compartment-specific manner. We developed a new approach to this problem by combining cell-specific physiological and anatomical characterization with super-resolution imaging and studied the molecular and structural parameters shaping the physiological properties of synaptic endocannabinoid signaling in the mouse hippocampus. We found that axon terminals of perisomatically projecting GABAergic interneurons possessed increased CB1 receptor number, active-zone complexity and receptor/effector ratio compared with dendritically projecting interneurons, consistent with higher efficiency of cannabinoid signaling at somatic versus dendritic synapses. Furthermore, chronic Δ(9)-tetrahydrocannabinol administration, which reduces cannabinoid efficacy on GABA release, evoked marked CB1 downregulation in a dose-dependent manner. Full receptor recovery required several weeks after the cessation of Δ(9)-tetrahydrocannabinol treatment. These findings indicate that cell type-specific nanoscale analysis of endogenous protein distribution is possible in brain circuits and identify previously unknown molecular properties controlling endocannabinoid signaling and cannabis-induced cognitive dysfunction.

  18. SPECT imaging of D2 dopamine receptors and endogenous dopamine release in mice

    NARCIS (Netherlands)

    Jongen, C.; De Bruin, K.; Beekman, F.J.; Booij, J.

    2008-01-01

    Purpose: The dopamine D2 receptor (D2R) is important in the mediation of addiction. [123I]iodobenzamide (IBZM), a SPECT ligand for the D2R, has been used for in vivo studies of D2R availability in humans, monkeys, and rats. Although mouse models are important in the study of addiction, [123I]IBZM

  19. NMDA receptor adjusted co-administration of ecstasy and cannabinoid receptor-1 agonist in the amygdala via stimulation of BDNF/Trk-B/CREB pathway in adult male rats.

    Science.gov (United States)

    Ashabi, Ghorbangol; Sadat-Shirazi, Mitra-Sadat; Khalifeh, Solmaz; Elhampour, Laleh; Zarrindast, Mohammad-Reza

    2017-04-01

    Consumption of cannabinoid receptor-1 (CB-1) agonist such as cannabis is widely taken in 3,4- methylenedioxymethamphetamine (MDMA) or ecstasy users; it has been hypothesized that co-consumption of CB-1 agonist might protect neurons against MDMA toxicity. N-methyl-d-aspartate (NMDA) receptors regulate neuronal plasticity and firing rate in the brain through Tyrosine-kinase B (Trk-B) activation. The molecular and electrophysiological association among NMDA and MDMA/Arachidonylcyclopropylamide (ACPA, a selective CB-1 receptor agonist) co-consumption was not well-known. Here, neuronal spontaneous activity, Brain-derived neurotrophic factor (BDNF), Trk-B and cAMP response element binding protein (CREB) phosphorylation levels were recognized in ACPA and MDMA co-injected rats. Besides, we proved the role of NMDA receptor on MDMA and ACPA combination on neuronal spontaneous activity and Trk-B/BDNF pathway in the central amygdala (CeA). Male rats were anesthetized with intra-peritoneal injections of urethane; MDMA, D-2-amino-5-phosphonopentanoate (D-AP5, NMDA receptor antagonist) were injected into CeA. ACPA was administrated by intra-cerebroventricular injection. Thirty minutes following injections, neuronal firing rate was recorded from CeA. Two hours after drug injection, amygdala was collected from brain for molecular evaluations. Single administration of MDMA and/or ACPA reduced firing rates compared with sham group in the CeA dose-dependently. Injection of D-AP5, ACPA and MDMA reduced firing rate compared with sham group (P<0.001). Interestingly, injection of ACPA+MDMA enhanced BDNF, Trk-B and CREB phosphorylation compared with MDMA groups. D-AP5, ACPA and MDMA co-injection decreased BDNF, Trk-B and CREB phosphorylation levels compared with ACPA+MDMA in the amygdala (P<0.01). Probably, NMDA receptors are involved in the protective role of acute MDMA+ACPA co-injection via BDNF/Trk-B/CREB pathways. Copyright © 2017 Elsevier Inc. All rights reserved.

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

    Science.gov (United States)

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

    2016-02-18

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

  1. Interactions of Cannabinoids With Biochemical Substrates

    Directory of Open Access Journals (Sweden)

    Brian F Thomas

    2017-05-01

    Full Text Available Recent decades have seen much progress in the identification and characterization of cannabinoid receptors and the elucidation of the mechanisms by which derivatives of the Cannabis sativa plant bind to receptors and produce their physiological and psychological effects. The information generated in this process has enabled better understanding of the fundamental physiological and psychological processes controlled by the central and peripheral nervous systems and has fostered the development of natural and synthetic cannabinoids as therapeutic agents. A negative aspect of this decades-long effort is the proliferation of clandestinely synthesized analogs as recreational street drugs with dangerous effects. Currently, the interactions of cannabinoids with their biochemical substrates are extensively but inadequately understood, and the clinical application of derived and synthetic receptor ligands remains quite limited. The wide anatomical distribution and functional complexity of the cannabinoid system continue to indicate potential for both therapeutic and side effects, which offers challenges and opportunities for medicinal chemists involved in drug discovery and development.

  2. Neurobiological mechanisms involved in nicotine dependence and reward: participation of the endogenous opioid system

    Science.gov (United States)

    Berrendero, Fernando; Robledo, Patricia; Trigo, José Manuel; Martín-García, Elena; Maldonado, Rafael

    2010-01-01

    Nicotine is the primary component of tobacco that maintains the smoking habit and develops addiction. The adaptive changes of nicotinic acetylcholine receptors produced by repeated exposure to nicotine play a crucial role in the establishment of dependence. However, other neurochemical systems also participate in the addictive effects of nicotine including glutamate, cannabinoids, GABA and opioids. This review will cover the involvement of these neurotransmitters in nicotine addictive properties, with a special emphasis on the endogenous opioid system. Thus, endogenous enkephalins and beta-endorphins acting on mu-opioid receptors are involved in nicotine rewarding effects, whereas opioid peptides derived from prodynorphin participate in nicotine aversive responses. An upregulation of mu-opioid receptors has been reported after chronic nicotine treatment that could counteract the development of nicotine tolerance, whereas the downregulation induced on kappa-opioid receptors seems to facilitate nicotine tolerance. Endogenous enkephalins acting on mu-opioid receptors also play a role in the development of physical dependence to nicotine. In agreement with these actions of the endogenous opioid system, the opioid antagonist naltrexone has shown to be effective for smoking cessation in certain subpopulations of smokers. PMID:20170672

  3. 3-Iodothyronamine, a Novel Endogenous Modulator of Transient Receptor Potential Melastatin 8?

    Directory of Open Access Journals (Sweden)

    Noushafarin Khajavi

    2017-08-01

    Full Text Available The decarboxylated and deiodinated thyroid hormone (TH derivative, 3-iodothyronamine (3-T1AM, is suggested to be involved in energy metabolism and thermoregulation. G protein-coupled receptors (GPCRs are known as the main targets for 3-T1AM; however, transient receptor potential channels (TRPs were also recently identified as new targets of 3-T1AM. This article reviews the current knowledge of a putative novel role of 3-T1AM in the modulation of TRPs. Specifically, the TRP melastatin 8 (TRPM8 was identified as a target of 3-T1AM in different cell types including neoplastic cells, whereby 3-T1AM significantly increased cytosolic Ca2+ through TRPM8 activation. Similarly, the β-adrenergic receptor is involved in 3-T1AM-induced Ca2+ influx. Therefore, it has been suggested that 3-T1AM-induced Ca2+ mobilization might be due to β-adrenergic receptor/TRPM8 channel interaction, which adds to the complexity of GPCR regulation by TRPs. It has been revealed that TRPM8 activation leads to a decline in TRPV1 activity, which may be of therapeutic benefit in clinical circumstances such as treatment of TRPV1-mediated inflammatory hyperalgesia, colitis, and dry eye syndrome. This review also summarizes the inverse association between changes in TRPM8 and TRPV1 activity after 3-T1AM stimulation. This finding prompted further detailed investigations of the interplay between 3-T1AM and the GPCR/TRPM8 axis and indicated the probability of additional GPCR/TRP constellations that are modulated by this TH derivative.

  4. Comparative metabolomics reveals endogenous ligands of DAF-12, a nuclear hormone receptor regulating C. elegans development and lifespan

    Science.gov (United States)

    Mahanti, Parag; Bose, Neelanjan; Bethke, Axel; Judkins, Joshua C.; Wollam, Joshua; Dumas, Kathleen J.; Zimmerman, Anna M.; Campbell, Sydney L.; Hu, Patrick J.; Antebi, Adam; Schroeder, Frank C.

    2014-01-01

    SUMMARY Small-molecule ligands of nuclear hormone receptors (NHRs) govern the transcriptional regulation of metazoan development, cell differentiation, and metabolism. However, the physiological ligands of many NHRs remain poorly characterized primarily due to lack of robust analytical techniques. Using comparative metabolomics, we identified endogenous steroids that act as ligands of the C. elegans NHR, DAF-12, a vitamin-D and liver-X receptor homolog regulating larval development, fat metabolism, and lifespan. The identified molecules feature unexpected chemical modifications and include only one of two DAF-12 ligands reported earlier, necessitating a revision of previously proposed ligand biosynthetic pathways. We further show that ligand profiles are regulated by a complex enzymatic network including the Rieske oxygenase DAF-36, the short-chain dehydrogenase DHS-16, and the hydroxysteroid dehydrogenase, HSD-1. Our results demonstrate the advantages of comparative metabolomics over traditional candidate-based approaches and provide a blueprint for the identification of ligands for other C. elegans and mammalian NHRs. PMID:24411940

  5. Cannabinoids modulate hippocampal memory and plasticity.

    Science.gov (United States)

    Abush, Hila; Akirav, Irit

    2010-10-01

    Considerable evidence demonstrates that cannabinoid agonists impair whereas cannabinoid antagonists improve memory and plasticity. However, recent studies suggest that the effects of cannabinoids on learning do not necessarily follow these simple patterns, particularly when emotional memory processes are involved. We investigated the involvement of the cannabinoid system in hippocampal learning and plasticity using the fear-related inhibitory avoidance (IA) and the non-fear-related spatial learning paradigms, and cellular models of learning and memory, i.e., long-term potentiation (LTP) and long-term depression (LTD). We found that microinjection into the CA1 of the CB1/CB2 receptor agonist WIN55,212-2 (5 μg/side) and an inhibitor of endocannabinoid reuptake and breakdown AM404 (200 ng/side) facilitated the extinction of IA, while the CB1 receptor antagonist AM251 (6 ng/side) impaired it. WIN55,212-2 and AM251 did not affect IA conditioning, while AM404 enhanced it, probably due to a drug-induced increase in pain sensitivity. However, in the water maze, systemic or local CA1 injections of AM251, WIN55,212-2, and AM404 all impaired spatial learning. We also found that i.p. administration of WIN55,212-2 (0.5 mg/kg), AM404 (10 mg/kg), and AM251 (2 mg/kg) impaired LTP in the Schaffer collateral-CA1 projection, whereas AM404 facilitated LTD. Our findings suggest diverse effects of the cannabinoid system on CA1 memory and plasticity that cannot be categorized simply into an impairing or an enhancing effect of cannabinoid activation and deactivation, respectively. Moreover, they provide preclinical support for the suggestion that targeting the endocannabinoid system may aid in the treatment of disorders associated with impaired extinction-like processes, such as post-traumatic stress disorder. © 2009 Wiley-Liss, Inc.

  6. Molecular basis of cannabinoid CB1 receptor coupling to the G protein heterotrimer Gαiβγ: identification of key CB1 contacts with the C-terminal helix α5 of Gαi.

    Science.gov (United States)

    Shim, Joong-Youn; Ahn, Kwang H; Kendall, Debra A

    2013-11-08

    The cannabinoid (CB1) receptor is a member of the rhodopsin-like G protein-coupled receptor superfamily. The human CB1 receptor, which is among the most expressed receptors in the brain, has been implicated in several disease states, including drug addiction, anxiety, depression, obesity, and chronic pain. Different classes of CB1 agonists evoke signaling pathways through the activation of specific subtypes of G proteins. The molecular basis of CB1 receptor coupling to its cognate G protein is unknown. As a first step toward understanding CB1 receptor-mediated G protein signaling, we have constructed a ternary complex structural model of the CB1 receptor and Gi heterotrimer (CB1-Gi), guided by the x-ray structure of β2-adrenergic receptor (β2AR) in complex with Gs (β2AR-Gs), through 824-ns duration molecular dynamics simulations in a fully hydrated 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine bilayer environment. We identified a group of residues at the juxtamembrane regions of the intracellular loops 2 and 3 (IC2 and IC3) of the CB1 receptor, including Ile-218(3.54), Tyr-224(IC2), Asp-338(6.30), Arg-340(6.32), Leu-341(6.33), and Thr-344(6.36), as potential key contacts with the extreme C-terminal helix α5 of Gαi. Ala mutations of these residues at the receptor-Gi interface resulted in little G protein coupling activity, consistent with the present model of the CB1-Gi complex, which suggests tight interactions between CB1 and the extreme C-terminal helix α5 of Gαi. The model also suggests that unique conformational changes in the extreme C-terminal helix α5 of Gα play a crucial role in the receptor-mediated G protein activation.

  7. 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...

  8. Activation of type-1 cannabinoid receptor shifts the balance between excitation and inhibition towards excitation in layer II/III pyramidal neurons of the rat prelimbic cortex

    NARCIS (Netherlands)

    den Boon, F.S.; Werkman, T.R.; Schaafsma-Zhao, Q.; Houthuijs, K.; Vitalis, T.; Kruse, C.G.; Wadman, W.J.; Chameau, P.

    2015-01-01

    Activation of the endocannabinoid (eCB) system by exogenous cannabinoids (drug abuse) can alter the physiology of the brain circuits involved in higher-order cognitive functions such as the medial prefrontal cortex (mPFC). A proper balance between excitation and inhibition (E/I balance) is critical

  9. Involvement of Gaba and Cannabinoid Receptors in Central Food Intake Regulation in Neonatal Layer Chicks: Role of CB1 and Gabaa Receptors

    Directory of Open Access Journals (Sweden)

    M Zendehdel

    Full Text Available ABSTRACT Feeding behavior is regulated via a complex network which interacts via diverse signals from central and peripheral tissues. Endocannabinoids modulate release of GABA in a variety of regions of the central nervous system. Endocannabinoids and GABAergic system have an important role in the central regulation of appetite. Thus, the present study examines the possible interaction of central canabinoidergic and GABAergic systems on food intake in 3-h food-deprived (FD3 neonatal layer-type chicks. The results of this study showed that intracerebroventricular (ICV injection of 2-AG (2-Arachidonoylglycerol, selective CB1 receptors agonist, 2µg significantly increased food intake and this effect of 2-AG was attenuated by Picrotoxin (GABAA antagonist, 0.5µg (P0.05. Also, hyperphagic effect of CB65 (CB2 receptors agonist, 1.25µg was not affected by Picrotoxin or CGP54626 (p>0.05. Moreover, the food intake of chicks was significantly increased by ICV injection of GABAA agonist (Gaboxadol, 0.2 µg and SR141716A (CB1 receptors antagonist, 6.25µg significantly decreased Gaboxadol-induced hyperphagia (P0.05. These data showed there might be an interaction between central cannabinoidergic and GABAergic systems via CB1 and GABAA receptors in control of food intake in neonatal layer chicks.

  10. Positron Emission Tomographic Imaging of the Cannabinoid Type 1 Receptor System with [11C]OMAR ([11C]JHU75528: Improvements in Image Quantification Using Wild-Type and Knockout Mice

    Directory of Open Access Journals (Sweden)

    Raúl Herance

    2011-11-01

    Full Text Available In this study, we assessed the feasibility of using positron emission tomography (PET and the tracer [11C]OMAR ([11C]JHU75528, an analogue of rimonabant, to study the brain cannabinoid type 1 (CB1 receptor system. Wild-type (WT andCB1 knockout (KO animals were imaged at baseline and after pretreatment with blocking doses of rimonabant. Brain uptake in WT animals was higher (50% than in KO animals in baseline conditions. After pretreatment with rimonabant, WT uptake lowered to the level of KO animals. The results of this study support the feasibility of using PET with the radiotracer [11C]JHU75528 to image the brain CB1 receptor system in mice. In addition, this methodology can be used to assess the effect of new drugs in preclinical studies using genetically manipulated animals.

  11. N-Acetyl-cysteine causes analgesia by reinforcing the endogenous activation of type-2 metabotropic glutamate receptors

    Directory of Open Access Journals (Sweden)

    Bernabucci Matteo

    2012-10-01

    pharmacological activation of Sxc- causes analgesia by reinforcing the endogenous activation of mGlu2 receptors. NAC has an excellent profile of safety and tolerability when clinically used as a mucolytic agent or in the management of acetaminophen overdose. Thus, our data encourage the use of NAC for the experimental treatment of inflammatory pain in humans.

  12. ITE, a novel endogenous nontoxic aryl hydrocarbon receptor ligand, efficiently suppresses EAU and T-cell-mediated immunity.

    Science.gov (United States)

    Nugent, Lindsey F; Shi, Guangpu; Vistica, Barbara P; Ogbeifun, Osato; Hinshaw, Samuel J H; Gery, Igal

    2013-11-13

    Ligands for aryl hydrocarbon receptor (AHR), such as dioxins, are highly toxic. One such ligand, TCDD, was found to exert potent immunosuppressive capacities in mice developing pathogenic autoimmune processes, including EAU, but its toxicity makes it unusable for humans. A recently identified endogenous AHR ligand, ITE, is also immunosuppressive, but is nontoxic and could therefore be useful for therapy in humans. Here, we tested ITE for its capacity to inhibit EAU and related immune responses. EAU was induced in B10.A mice by immunization with interphotoreceptor retinoid-binding protein (IRBP; 40 μg) in CFA. Treatment with ITE was by daily intraperitoneal injection of 0.2 mg. Disease severity was assessed by both fundoscopy and histological examination. Draining lymph node cells were tested for proliferation by thymidine uptake and for cytokine production and release by ELISA. In addition, the intracellular expression of cytokines and Foxp3 was determined by flow cytometry. Serum antibodies were measured by ELISA. Treatment with ITE efficiently inhibited the development of EAU in mice, as well as the cellular immune responses against IRBP and PPD. ITE treatment inhibited the expansion of both Th1 and Th17 subpopulations, as well as their release of the signature cytokines, IFN-gamma and IL-17. The treatment moderately increased, however, the proportion of Foxp3 expressing T-regulatory cells. Antibody production was not affected by the treatment. ITE, an endogenous AHR ligand, efficiently inhibits EAU development and related cellular immune responses. Being nontoxic, ITE may be considered for treatment of pathogenic immunity in humans.

  13. ITE, A Novel Endogenous Nontoxic Aryl Hydrocarbon Receptor Ligand, Efficiently Suppresses EAU and T-Cell–Mediated Immunity

    Science.gov (United States)

    Nugent, Lindsey F.; Shi, Guangpu; Vistica, Barbara P.; Ogbeifun, Osato; Hinshaw, Samuel J. H.; Gery, Igal

    2013-01-01

    Purpose. Ligands for aryl hydrocarbon receptor (AHR), such as dioxins, are highly toxic. One such ligand, TCDD, was found to exert potent immunosuppressive capacities in mice developing pathogenic autoimmune processes, including EAU, but its toxicity makes it unusable for humans. A recently identified endogenous AHR ligand, ITE, is also immunosuppressive, but is nontoxic and could therefore be useful for therapy in humans. Here, we tested ITE for its capacity to inhibit EAU and related immune responses. Methods. EAU was induced in B10.A mice by immunization with interphotoreceptor retinoid-binding protein (IRBP; 40 μg) in CFA. Treatment with ITE was by daily intraperitoneal injection of 0.2 mg. Disease severity was assessed by both fundoscopy and histological examination. Draining lymph node cells were tested for proliferation by thymidine uptake and for cytokine production and release by ELISA. In addition, the intracellular expression of cytokines and Foxp3 was determined by flow cytometry. Serum antibodies were measured by ELISA. Results. Treatment with ITE efficiently inhibited the development of EAU in mice, as well as the cellular immune responses against IRBP and PPD. ITE treatment inhibited the expansion of both Th1 and Th17 subpopulations, as well as their release of the signature cytokines, IFN-gamma and IL-17. The treatment moderately increased, however, the proportion of Foxp3 expressing T-regulatory cells. Antibody production was not affected by the treatment. Conclusions. ITE, an endogenous AHR ligand, efficiently inhibits EAU development and related cellular immune responses. Being nontoxic, ITE may be considered for treatment of pathogenic immunity in humans. PMID:24150760

  14. Cannabinoids reduce markers of inflammation and fibrosis in pancreatic stellate cells.

    Directory of Open Access Journals (Sweden)

    Christoph W Michalski

    2008-02-01

    Full Text Available While cannabinoids have been shown to ameliorate liver fibrosis, their effects in chronic pancreatitis and on pancreatic stellate cells (PSC are unknown.The activity of the endocannabinoid system was evaluated in human chronic pancreatitis (CP tissues. In vitro, effects of blockade and activation of cannabinoid receptors on pancreatic stellate cells were characterized. In CP, cannabinoid receptors were detected predominantly in areas with inflammatory changes, stellate cells and nerves. Levels of endocannabinoids were decreased compared with normal pancreas. Cannabinoid-receptor-1 antagonism effectuated a small PSC phenotype and a trend toward increased invasiveness. Activation of cannabinoid receptors, however, induced de-activation of PSC and dose-dependently inhibited growth and decreased IL-6 and MCP-1 secretion as well as fibronectin, collagen1 and alphaSMA levels. De-activation of PSC was partially reversible using a combination of cannabinoid-receptor-1 and -2 antagonists. Concomitantly, cannabinoid receptor activation specifically decreased invasiveness of PSC, MMP-2 secretion and led to changes in PSC phenotype accompanied by a reduction of intracellular stress fibres.Augmentation of the endocannabinoid system via exogenously administered cannabinoid receptor agonists specifically induces a functionally and metabolically quiescent pancreatic stellate cell phenotype and may thus constitute an option to treat inflammation and fibrosis in chronic pancreatitis.

  15. The effects of leptin in combination with a cannabinoid receptor 1 antagonist, AM 251, or cannabidiol on food intake and body weight in rats fed a high-fat or a free-choice high sugar diet.

    Science.gov (United States)

    Wierucka-Rybak, M; Wolak, M; Bojanowska, E

    2014-08-01

    High intake of fats and sugars has prompted a rapid growth in the number of obese individuals worldwide. To further investigate whether simultaneous pharmacological intervention in the leptin and cannabinoid system might change food and water intake, preferences for palatable foods, and body weight, we have examined the effects of concomitant intraperitoneal administration of leptin and AM 251, a cannabinoid 1 (CB1) receptor antagonist, or cannabidiol (CBD), a plant cannabinoid, in rats maintained on either a high-fat (HF) diet (45% energy from fat) or free-choice (FC) diet consisting of high-sucrose and normal rat chow (83% and 61% energy from carbohydrates, respectively). Leptin at a dose of 100 μg/kg injected individually for 3 subsequent days to rats fed a HF diet reduced significantly the daily caloric intake and inhibited body weight gain. The hormone had no significant effects, however, on either caloric intake, body weight or food preferences in rats fed an FC diet. Co-injection of leptin and 1 mg/kg AM 251 resulted in a further significant decrease in HF diet intake and a profound reduction in body weight gain both in HF diet- and FC diet-fed rats. This drug combination, however, had no effect on the consumption of high-sucrose chow. In contrast, 3mg/kg of CBD co-injected with leptin did not modify leptin effects on food intake in rats maintained on an FC or HF diet. None of the drug combinations affected water consumption. It is concluded that the concomitant treatment with leptin and AM 251 attenuated markedly body weight gain in rats maintained on high-calorie diets rich in fat and carbohydrates but did not affect preferences for sweet food.

  16. Canabinoides: análogos y perspectivas terapéuticas II Cannabinoids: analogues and therapeutical perspectivas II

    Directory of Open Access Journals (Sweden)

    Juan E. Tacoronte Morales

    2008-12-01

    Full Text Available Actualmente se han generado valiosísimas fuentes de información que correlacionan la especie botánica Cannabis sativa L y sus metabolitos secundarios con la medicina (tratamiento terapéutico, farmacología (modelos experimentales y química sintética (diseño y generación de nuevas estructuras y análogos bioisósteres, que avalan la significación del estudio de esta planta, sus extractos, metabolitos, precursores y análogos naturales y sintéticos como fuente de agentes terapéuticos. Por tal motivo se presenta una revisión de la información existente sobre las potenciales implicaciones terapéuticas de sistemas moleculares canabinoidales (endógenos, naturales y sintéticos en el tratamiento de diversas afecciones del sistema nervioso central, que incluye: conceptos de tipos de canabinoides; sistemas de receptores canabinoides CB1 y CB2 y sus ligandos así como evidencias preclínicas de los efectos terapéuticos de canabinoides desde 1970 hasta el 2006.At present, a great amount of valuable information and experimental data has been generated that correlate Cannabis sativa and its secondary metabolites with medicine (therapeutic treatment, pharmacology (experimental animal models and synthetic chemistry (design and generation of new structures and biososteric analogues, showing the importance of the study about this plant, its extracts, metabolite precursors and natural and synthetic analogues as therapeutic agents. Taking theses points into consideration, this article reviews the therapeutic implications of cannabinoid systems (endogenous, natural, and synthetic on several pathologies of central nervous system, including: cannabinoid type concepts, cannabinoid receptor systems CB1 and CB2 and preclinical studies devoted to therapeutic effects of the cannabinoids since 1970 until 2006

  17. The Structure–Function Relationships of Classical Cannabinoids: CB1/CB2 Modulation

    Science.gov (United States)

    Bow, Eric W.; Rimoldi, John M.

    2016-01-01

    The cannabinoids are members of a deceptively simple class of terpenophenolic secondary metabolites isolated from Cannabis sativa highlighted by (−)-Δ9-tetrahydrocannabinol (THC), eliciting distinct pharmacological effects mediated largely by cannabinoid receptor (CB1 or CB2) signaling. Since the initial discovery of THC and related cannabinoids, synthetic and semisynthetic classical cannabinoid analogs have been evaluated to help define receptor binding modes and structure–CB1/CB2 functional activity relationships. This perspective will examine the classical cannabinoids, with particular emphasis on the structure–activity relationship of five regions: C3 side chain, phenolic hydroxyl, aromatic A-ring, pyran B-ring, and cyclohexenyl C-ring. Cumulative structure–activity relationship studies to date have helped define the critical structural elements required for potency and selectivity toward CB1 and CB2 and, more importantly, ushered the discovery and development of contemporary nonclassical cannabinoid modulators with enhanced physicochemical and pharmacological profiles. PMID:27398024

  18. [Short-and long-term effects of cannabinoids on memory, cognition and mental illness].

    Science.gov (United States)

    Sagie, Shira; Eliasi, Yehuda; Livneh, Ido; Bart, Yosi; Monovich, Einat

    2013-12-01

    Marijuana is considered the most commonly used drug in the world, with estimated millions of users. There is dissent in the medical world about the positive and negative effects of marijuana, and recently, a large research effort has been directed to that domain. The main influencing drug ingredient is THC, which acts on the cannabinoid system and binds to the CB1 receptor. The discovery of the receptor led to the finding of an endogenous ligand, anandamide, and another receptor-CB2. The researchers also discovered that cannabinoids have extensive biological activity, and its short and long-term effects may cause cognitive and emotional deficiencies. Findings show that the short-term effects, such as shortterm memory and verbal Learning, are reversible. However, despite the accumulation of evidence about long-term cognitive damage due to cannabis use, it is difficult to find unequivocal results, arising from the existence of many variables such as large differences between cannabis users, frequency of use, dosage and endogenous brain compensation. Apart from cognitive damage, current studies investigate how marijuana affects mental illness: a high correlation between cannabis use and schizophrenia was found and a high risk to undergo a psychotic attack. Furthermore, patients with schizophrenia who used cannabis showed a selective neuro-psychological disruption, and similar cognitive deficiencies and brain morphological changes were found among healthy cannabis users and schizophrenia patients. In contrast to the negative effects of marijuana including addiction, there are the medical uses: reducing pain, anxiety and nausea, increasing appetite and an anti-inflammatory activity. Medicalization of marijuana encourages frequent use, which may elevate depression.

  19. 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.

    Science.gov (United States)

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

    2015-03-01

    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. This compound deviates from earlier JHW-type synthetic cannabinoids by having an indazole ring connected to an adamantyl group via a carboxamide linkage. Synthetic cannabinoids are completely metabolized, and identification of the metabolites is thus crucial when using urine as the sample matrix. Using an authentic urine sample and high-resolution accurate-mass Fourier transform Orbitrap mass spectrometry, we identified 16 phase-I metabolites of 5F-AKB-48. The modifications included mono-, di-, and trihydroxylation on the adamantyl ring alone or in combination with hydroxylation on the N-fluoropentylindazole moiety, dealkylation of the N-fluoropentyl side chain, and oxidative loss of fluorine as well as combinations thereof. The results were compared to human liver microsomal (HLM) incubations, which predominantly showed time-dependent formation of mono-, di-, and trihydroxylated metabolites having the hydroxyl groups on the adamantyl ring. The results presented here may be used to select metabolites specific of 5F-AKB-48 for use in clinical and forensic screening. Copyright © 2014 John Wiley & Sons, Ltd.

  20. Endogenous opioid peptide-mediated neurotransmission in central and pericentral nuclei of the inferior colliculus recruits μ1-opioid receptor to modulate post-ictal antinociception.

    Science.gov (United States)

    Felippotti, Tatiana Tocchini; de Freitas, Renato Leonardo; Coimbra, Norberto Cysne

    2012-02-01

    The aim of the present work was to investigate the involvement of the μ1-endogenous opioid peptide receptor-mediated system in post-ictal antinociception. Antinociceptive responses were determined by the tail-flick test after pre-treatment with the selective μ1-opioid receptor antagonist naloxonazine, peripherally or centrally administered at different doses. Peripheral subchronic (24 h) pre-treatment with naloxonazine antagonised the antinociception elicited by tonic-clonic seizures. Acute (10 min) pre-treatment, however, did not have the same effect. In addition, microinjections of naloxonazine into the central, dorsal cortical and external cortical nuclei of the inferior colliculus antagonised tonic-clonic seizure-induced antinociception. Neither acute (10-min) peripheral pre-treatment with naloxonazine nor subchronic intramesencephalic blockade of μ1-opioid receptors resulted in consistent statistically significant differences in the severity of tonic-clonic seizures shown by Racine's index (1972), although the intracollicular specific antagonism of μ1-opioid receptor decreased the duration of seizures. μ1-Opioid receptors and the inferior colliculus have been implicated in several endogenous opioid peptide-mediated responses such as antinociception and convulsion. The present findings suggest the involvement of μ1-opiate receptors of central and pericentral nuclei of the inferior colliculus in the modulation of tonic-clonic seizures and in the organisation of post-ictal antinociception. Copyright © 2011 Elsevier Ltd. All rights reserved.

  1. 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.

  2. Cannabinoid-Induced Changes in the Activity of Electron Transport Chain Complexes of Brain Mitochondria.

    Science.gov (United States)

    Singh, Namrata; Hroudová, Jana; Fišar, Zdeněk

    2015-08-01

    The aim of this study was to investigate changes in the activity of individual mitochondrial respiratory chain complexes (I, II/III, IV) and citrate synthase induced by pharmacologically different cannabinoids. In vitro effects of selected cannabinoids on mitochondrial enzymes were measured in crude mitochondrial fraction isolated from pig brain. Both cannabinoid receptor agonists, Δ(9)-tetrahydrocannabinol, anandamide, and R-(+)-WIN55,212-2, and antagonist/inverse agonists of cannabinoid receptors, AM251, and cannabidiol were examined in pig brain mitochondria. Different effects of these cannabinoids on mitochondrial respiratory chain complexes and citrate synthase were found. Citrate synthase activity was decreased only by Δ(9)-tetrahydrocannabinol and AM251. Significant increase in the complex I activity was induced by anandamide. At micromolar concentration, all the tested cannabinoids inhibited the activity of electron transport chain complexes II/III and IV. Stimulatory effect of anandamide on activity of complex I may participate on distinct physiological effects of endocannabinoids compared to phytocannabinoids or synthetic cannabinoids. Common inhibitory effect of cannabinoids on activity of complex II/III and IV confirmed a non-receptor-mediated mechanism of cannabinoid action on individual components of system of oxidative phosphorylation.

  3. Combination of exogenous cell transplantation and 5-HT4 receptor agonism induce endogenous enteric neural crest-derived cells in a rat hypoganglionosis model.

    Science.gov (United States)

    Yu, Hui; Zheng, Bai-Jun; Pan, Wei-Kang; Wang, Huai-Jie; Xie, Chong; Zhao, Yu-Ying; Chen, Xin-Lin; Liu, Yong; Gao, Ya

    2017-02-01

    Enteric neural crest-derived cells (ENCCs) can migrate into endogenous ganglia and differentiate into progeny cells, and have even partially rescued bowel function; however, poor reliability and limited functional recovery after ENCC transplantation have yet to be addressed. Here, we investigated the induction of endogenous ENCCs by combining exogenous ENCC transplantation with a 5-HT 4 receptor agonist mosapride in a rat model of hypoganglionosis, established by benzalkonium chloride treatment. ENCCs, isolated from the gut of newborn rats, were labeled with a lentiviral eGFP reporter. ENCCs and rats were treated with the 5-HT 4 receptor agonist/antagonist. The labeled ENCCs were then transplanted into the muscular layer of benzalkonium chloride-treated colons. At given days post-intervention, colonic tissue samples were removed for histological analysis. ENCCs and neurons were detected by eGFP expression and immunoreactivity to p75 NTR and peripherin, respectively. eGFP-positive ENCCs and neurons could survive and maintain levels of fluorescence after transplantation. With longer times post-intervention, the number of peripherin-positive cells gradually increased in all groups. Significantly more peripherin-positive cells were found following ENCCs plus mosapride treatment, compared with the other groups. These results show that exogenous ENCCs combined with the 5-HT 4 receptor agonist effectively induced endogenous ENCCs proliferation and differentiation in a rat hypoganglionosis model. Copyright © 2016 Elsevier Inc. All rights reserved.

  4. Epac is required for exogenous and endogenous stimulation of adenosine A2B receptor for inhibition of angiotensin II-induced collagen synthesis and myofibroblast differentiation.

    Science.gov (United States)

    Phosri, Sarawuth; Bunrukchai, Kwanchai; Parichatikanond, Warisara; Sato, Vilasinee H; Mangmool, Supachoke

    2018-01-10

    Angiotensin II (Ang II) plays an important role on the pathogenesis of cardiac fibrosis. Prolong and overstimulation of angiotensin II type 1 receptor with Ang II-induced collagen synthesis and myofibroblast differentiation in cardiac fibroblasts, leading to cardiac fibrosis. Although adenosine and its analogues are known to have cardioprotective effects, the mechanistic by which adenosine A 2 receptors (A 2 Rs) inhibit Ang II-induced cardiac fibrosis is not clearly understood. In the present study, we examined the effects of exogenous adenosine and endogenous adenosine on Ang II-induced collagen and myofibroblast differentiation determined by α-smooth muscle action (α-SMA) overexpression and their underlying signal transduction. Elevation of endogenous adenosine levels resulted in the inhibition of Ang II-induced collagen type I and III and α-SMA synthesis in cardiac fibroblasts. Moreover, treatment with exogenous adenosine which selectively stimulated A 2 Rs also suppressed Ang II-induced collagen synthesis and α-SMA production. These antifibrotic effects of both endogenous and exogenous adenosines are mediated through the A 2B receptor (A 2B R) subtype. Stimulation of A 2B R exhibited antifibrotic effects via the cAMP-dependent and Epac-dependent pathways. Our results provide new mechanistic insights regarding the role for cAMP and Epac on A 2B R-mediated antifibrotic effects. Thus, A 2B R is one of the potential therapeutic targets against cardiac fibrosis.

  5. Molecular mechanisms underlying the effects of cannabinoids in the brain

    OpenAIRE

    Puighermanal Puigvert, Emma, 1983-

    2011-01-01

    El sistema endocannabinoid és un sistema neuromodulador endogen que regula diverses funcions fisiològiques, incloent el control del moviment, la memòria, l’ansietat i el dolor, entre altres. Els compostos cannabinoids es troben principalment a la planta Cannabis sativa i exerceixen els seus efectes actuant al sistema endocannabinoid. Els cannabinoids tenen potencial terapèutic, principalment per l’esclerosi múltiple, el dolor i l’èmesi, tot i que una limitació important pel seu ús recau en el...

  6. An endogenous aryl hydrocarbon receptor (AhR) ligand, ITE induces regulatory T cells (Tregs) and ameliorates experimental colitis.

    Science.gov (United States)

    Abron, Jessicca D; Singh, Narendra P; Mishra, Manoj K; Price, Robert L; Nagarkatti, Mitzi; Nagarkatti, Prakash S; Singh, Udai P

    2018-04-19

    Inflammatory bowel disease (IBD) is a chronic intestinal inflammatory condition that affects millions of people with high morbidity and health-care cost. The precise etiology of IBD is unknown, but clear evidence suggests that intestinal inflammation is caused by an excessive immune response to mucosal antigens. Recent studies have shown that activation of the aryl hydrocarbon receptor (AhR) induces regulatory T cells (Tregs) and suppresses autoimmune diseases. In the current study, we investigated if nontoxic ligand of AhR, 2-(1'H-indole-3'-carbonyl)-thiazole-4-carboxylic acid methyl ester (ITE), can attenuate dextran sodium sulphate (DSS)-induced colitis. Our studies demonstrated that in mice that received ITE treatment, in-vivo colitis pathogenesis, including a decrease in body weight, was significantly reversed along with the systemic and intestinal inflammatory cytokines. ITE increased the expression of Tregs in spleen, mesenteric lymph nodes (MLNs) and colon lamina propria lymphocytes (cLPL) of mice with colitis when compared to controls. This induction of Tregs was reversed by AhR antagonist treatment in-vitro. ITE treatment also increased dendritic cells (DCs; CD11c+) and decreased F4/80+ (macrophage) from the spleen, MLNs and cLPL in mice with colitis. ITE also reversed the systemic and intestinal frequency of CD4+T cells during colitis and suppressed inflammatory cytokines including IFN-γ, TNF-α, IL-17, IL-6 and IL-1 as well as induced IL-10 levels. These findings suggest that ITE attenuates colitis through induction of Tregs and reduction in inflammatory CD4+ T cells and cytokines. Thus, our work demonstrates that the nontoxic endogenous AhR ligand ITE, may serve as a therapeutic modality to treat IBD.

  7. Comparison of the convergent receptor utilization of a retargeted feline leukemia virus envelope with a naturally-occurring porcine endogenous retrovirus A.

    Science.gov (United States)

    Mazari, Peter M; Argaw, Takele; Valdivieso, Leonardo; Zhang, Xia; Marcucci, Katherine T; Salomon, Daniel R; Wilson, Carolyn A; Roth, Monica J

    2012-06-05

    In vitro screening of randomized FeLV Envelope libraries identified the CP isolate, which enters cells through HuPAR-1, one of two human receptors utilized by porcine endogenous retrovirus-A (PERV-A), a distantly related gammaretrovirus. The CP and PERV-A Envs however, share little amino acid homology. Their receptor utilization was examined to define the common receptor usage of these disparate viral Envs. We demonstrate that the receptor usage of CP extends to HuPAR-2 but not to the porcine receptor PoPAR, the cognate receptor for PERV-A. Reciprocal interference between virus expressing CP and PERV-A Envs was observed on human cells. Amino acid residues localized to within the putative second extracellular loop (ECL-2) of PAR-1 and PAR-2 are found to be critical for CP envelope function. Through a panel of receptor chimeras and point mutations, this area was also found to be responsible for the differential usage of the PoPAR receptor between CP and PERV-A. Copyright © 2012 Elsevier Inc. All rights reserved.

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

    Science.gov (United States)

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

    2010-01-01

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

  9. Studies of the brain cannabinoid system using positron emission tomography

    Energy Technology Data Exchange (ETDEWEB)

    Gatley, S.J.; Volkow, N.D.

    1995-10-01

    Studies using radiolabeled psychoactive drugs in conjunction with positron emission tomography (PET) have permitted the imaging of binding sites in the human brain. Similar studies of marijuana have been hampered by the unsuitability of radiolabeled THC for PET studies, and the current unavailability of other in vivo imaging agents for cannabinoid receptors. Recent developments in medicinal chemistry suggest that a PET radiotracer for cannabinoid receptors will soon become available. This chapter briefly reviews these developments, together with the results of PET studies of the effects of marijuana and other abused drugs on brain metabolism. It also reviews PET studies of cocaine binding sites, to demonstrate the kind of investigations that will be possible when a cannabinoid receptor PET radioligand becomes available.

  10. Studies of the brain cannabinoid system using positron emission tomography

    International Nuclear Information System (INIS)

    Gatley, S.J.; Volkow, N.D.

    1995-01-01

    Studies using radiolabeled psychoactive drugs in conjunction with positron emission tomography (PET) have permitted the imaging of binding sites in the human brain. Similar studies of marijuana have been hampered by the unsuitability of radiolabeled THC for PET studies, and the current unavailability of other in vivo imaging agents for cannabinoid receptors. Recent developments in medicinal chemistry suggest that a PET radiotracer for cannabinoid receptors will soon become available. This chapter briefly reviews these developments, together with the results of PET studies of the effects of marijuana and other abused drugs on brain metabolism. It also reviews PET studies of cocaine binding sites, to demonstrate the kind of investigations that will be possible when a cannabinoid receptor PET radioligand becomes available

  11. 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.

  12. In vivo imaging of estrogen receptor concentration in the endometrium and myometrium using FES PET - influence of menstrual cycle and endogenous estrogen level

    International Nuclear Information System (INIS)

    Tsuchida, Tatsuro; Okazawa, Hidehiko; Mori, Tetsuya; Kobayashi, Masato; Yoshida, Yoshio; Fujibayashi, Yasuhisa; Itoh, Harumi

    2007-01-01

    Purpose: The goals of this study were to measure estrogen receptor (ER) concentration in the endometrium and myometrium using 16α-[ 18 F]fluoro-17β-estradiol (FES) positron emission tomography (PET) and to investigate the relationship between changes in these parameters with the menstrual cycle and endogenous estrogen levels. Methods: Sixteen female healthy volunteers were included in this study. After blood sampling to measure endogenous estrogen level, FES PET image was acquired 60 min postinjection of FES. After whole-body imaging of FES PET, averaged standardized uptake values (SUVs) in the endometrium and myometrium were measured, and the relationship between FES uptake and menstrual cycle or endogenous estrogen level was evaluated. Results: Endometrial SUV was significantly higher in the proliferative phase than in the secretory phase (6.03±1.05 vs. 3.97±1.29, P=.022). In contrast, there was no significant difference in myometrial SUV when the proliferative and secretory phases were compared (P=.23). Further, there was no correlation between SUV and endogenous estrogen level in the proliferative phase. Conclusions: The change of ER concentration relative to menstrual cycle as characterized by FES PET was consistent with those from previous reports that used an immunohistochemical technique. These data suggest that FES PET is a feasible, noninvasive method for characterizing changes in ER concentration

  13. In vivo imaging of estrogen receptor concentration in the endometrium and myometrium using FES PET - influence of menstrual cycle and endogenous estrogen level

    Energy Technology Data Exchange (ETDEWEB)

    Tsuchida, Tatsuro [Department of Radiology, Faculty of Medical Sciences, University of Fukui, Yoshida-gun, Fukui 910-1193 (Japan)]. E-mail: tsucchy@fmsrsa.fukui-med.ac.jp; Okazawa, Hidehiko [Biomedical Imaging Research Center, University of Fukui, Yoshida-gun, Fukui 910-1193 (Japan); Mori, Tetsuya [Biomedical Imaging Research Center, University of Fukui, Yoshida-gun, Fukui 910-1193 (Japan); Kobayashi, Masato [Biomedical Imaging Research Center, University of Fukui, Yoshida-gun, Fukui 910-1193 (Japan); Yoshida, Yoshio [Department of Obstetrics and Gynecology, Faculty of Medical Sciences, University of Fukui, Yoshida-gun, Fukui 910-1193 (Japan); Fujibayashi, Yasuhisa [Biomedical Imaging Research Center, University of Fukui, Yoshida-gun, Fukui 910-1193 (Japan); Itoh, Harumi [Department of Radiology, Faculty of Medical Sciences, University of Fukui, Yoshida-gun, Fukui 910-1193 (Japan)

    2007-02-15

    Purpose: The goals of this study were to measure estrogen receptor (ER) concentration in the endometrium and myometrium using 16{alpha}-[{sup 18}F]fluoro-17{beta}-estradiol (FES) positron emission tomography (PET) and to investigate the relationship between changes in these parameters with the menstrual cycle and endogenous estrogen levels. Methods: Sixteen female healthy volunteers were included in this study. After blood sampling to measure endogenous estrogen level, FES PET image was acquired 60 min postinjection of FES. After whole-body imaging of FES PET, averaged standardized uptake values (SUVs) in the endometrium and myometrium were measured, and the relationship between FES uptake and menstrual cycle or endogenous estrogen level was evaluated. Results: Endometrial SUV was significantly higher in the proliferative phase than in the secretory phase (6.03{+-}1.05 vs. 3.97{+-}1.29, P=.022). In contrast, there was no significant difference in myometrial SUV when the proliferative and secretory phases were compared (P=.23). Further, there was no correlation between SUV and endogenous estrogen level in the proliferative phase. Conclusions: The change of ER concentration relative to menstrual cycle as characterized by FES PET was consistent with those from previous reports that used an immunohistochemical technique. These data suggest that FES PET is a feasible, noninvasive method for characterizing changes in ER concentration.

  14. The multidrug transporter ABCG2 (BCRP) is inhibited by plant-derived cannabinoids.

    Science.gov (United States)

    Holland, M L; Lau, D T T; Allen, J D; Arnold, J C

    2007-11-01

    Cannabinoids are used therapeutically for the palliation of the adverse side effects associated with cancer chemotherapy. However, cannabinoids also inhibit both the activity and expression of the multidrug transporter, P-glycoprotein in vitro. Here we address the interaction of cannabinol (CBN), cannabidiol (CBD) and delta 9-tetrahydrocannabinol (THC) with the related multidrug transporter, ABCG2. Cannabinoid inhibition of Abcg2/ABCG2 was assessed using flow cytometric analysis of substrate accumulation and ATPase activity assays. The cytotoxicity and chemosensitization by cannabinoids was determined with cell viability assays. Expression of cannabinoid and vanilloid receptors was assessed using reverse transcriptase polymerase chain reaction, and cannabinoid modulation of ABCG2 expression was examined using immunoblotting. CBN, CBD and THC increased the intracellular accumulation of the Abcg2/ABCG2 substrate, mitoxantrone, in an over-expressing cell line. The THC metabolite, (-)-11-nor-9-carboxy-delta 9-THC was much less potent. The plant cannabinoids inhibited both basal and substrate stimulated ATPase activity of human ABCG2. Cannabinoid cytotoxicity occurred in the absence of known cannabinoid cell surface receptors, and only at concentrations higher than those required for Abcg2/ABCG2 inhibition. Sub-toxic concentrations of the cannabinoids resensitized the overexpressing cell line to the cytotoxic effect of Abcg2/ABCG2 substrates, mitoxantrone and topotecan. This occurred in the absence of any effect on ABCG2 expression. Cannabinoids are novel Abcg2/ABCG2 inhibitors, reversing the Abcg2-mediated multidrug-resistant phenotype in vitro. This finding may have implications for the co-administration of cannabinoids with pharmaceuticals that are ABCG2 substrates.

  15. Combination of exogenous cell transplantation and 5-HT{sub 4} receptor agonism induce endogenous enteric neural crest-derived cells in a rat hypoganglionosis model

    Energy Technology Data Exchange (ETDEWEB)

    Yu, Hui [Department of Pediatric Surgery, the Second Affiliated Hospital, Xi’an Jiaotong University, No 157, Xi Wu Road, Xi’an 710004, Shaanxi (China); Institute of Neurobiology, Environment and Genes Related to Diseases Key Laboratory of Chinese Ministry of Education, Xi’an Jiaotong University, No 96, Yan Ta Xi Road, Xi’an 710061, Shaanxi (China); Zheng, Bai-Jun; Pan, Wei-Kang; Wang, Huai-Jie; Xie, Chong; Zhao, Yu-Ying [Department of Pediatric Surgery, the Second Affiliated Hospital, Xi’an Jiaotong University, No 157, Xi Wu Road, Xi’an 710004, Shaanxi (China); Chen, Xin-Lin; Liu, Yong [Institute of Neurobiology, Environment and Genes Related to Diseases Key Laboratory of Chinese Ministry of Education, Xi’an Jiaotong University, No 96, Yan Ta Xi Road, Xi’an 710061, Shaanxi (China); Gao, Ya, E-mail: ygao@mail.xjtu.edu.cn [Department of Pediatric Surgery, the Second Affiliated Hospital, Xi’an Jiaotong University, No 157, Xi Wu Road, Xi’an 710004, Shaanxi (China)

    2017-02-01

    Enteric neural crest-derived cells (ENCCs) can migrate into endogenous ganglia and differentiate into progeny cells, and have even partially rescued bowel function; however, poor reliability and limited functional recovery after ENCC transplantation have yet to be addressed. Here, we investigated the induction of endogenous ENCCs by combining exogenous ENCC transplantation with a 5-HT{sub 4} receptor agonist mosapride in a rat model of hypoganglionosis, established by benzalkonium chloride treatment. ENCCs, isolated from the gut of newborn rats, were labeled with a lentiviral eGFP reporter. ENCCs and rats were treated with the 5-HT{sub 4} receptor agonist/antagonist. The labeled ENCCs were then transplanted into the muscular layer of benzalkonium chloride-treated colons. At given days post-intervention, colonic tissue samples were removed for histological analysis. ENCCs and neurons were detected by eGFP expression and immunoreactivity to p75{sup NTR} and peripherin, respectively. eGFP-positive ENCCs and neurons could survive and maintain levels of fluorescence after transplantation. With longer times post-intervention, the number of peripherin-positive cells gradually increased in all groups. Significantly more peripherin-positive cells were found following ENCCs plus mosapride treatment, compared with the other groups. These results show that exogenous ENCCs combined with the 5-HT{sub 4} receptor agonist effectively induced endogenous ENCCs proliferation and differentiation in a rat hypoganglionosis model. - Highlights: • Survival and differentiation of exogenous ENCCs in treated colons. • With longer times post-intervention, the number of ENCCs and their progeny cells gradually increased. • Exogenous ENCCs combined with the 5-HT4 receptor agonist ffectively induced ENCCs proliferation and differentiation.

  16. Combination of exogenous cell transplantation and 5-HT4 receptor agonism induce endogenous enteric neural crest-derived cells in a rat hypoganglionosis model

    International Nuclear Information System (INIS)

    Yu, Hui; Zheng, Bai-Jun; Pan, Wei-Kang; Wang, Huai-Jie; Xie, Chong; Zhao, Yu-Ying; Chen, Xin-Lin; Liu, Yong; Gao, Ya

    2017-01-01

    Enteric neural crest-derived cells (ENCCs) can migrate into endogenous ganglia and differentiate into progeny cells, and have even partially rescued bowel function; however, poor reliability and limited functional recovery after ENCC transplantation have yet to be addressed. Here, we investigated the induction of endogenous ENCCs by combining exogenous ENCC transplantation with a 5-HT 4 receptor agonist mosapride in a rat model of hypoganglionosis, established by benzalkonium chloride treatment. ENCCs, isolated from the gut of newborn rats, were labeled with a lentiviral eGFP reporter. ENCCs and rats were treated with the 5-HT 4 receptor agonist/antagonist. The labeled ENCCs were then transplanted into the muscular layer of benzalkonium chloride-treated colons. At given days post-intervention, colonic tissue samples were removed for histological analysis. ENCCs and neurons were detected by eGFP expression and immunoreactivity to p75 NTR and peripherin, respectively. eGFP-positive ENCCs and neurons could survive and maintain levels of fluorescence after transplantation. With longer times post-intervention, the number of peripherin-positive cells gradually increased in all groups. Significantly more peripherin-positive cells were found following ENCCs plus mosapride treatment, compared with the other groups. These results show that exogenous ENCCs combined with the 5-HT 4 receptor agonist effectively induced endogenous ENCCs proliferation and differentiation in a rat hypoganglionosis model. - Highlights: • Survival and differentiation of exogenous ENCCs in treated colons. • With longer times post-intervention, the number of ENCCs and their progeny cells gradually increased. • Exogenous ENCCs combined with the 5-HT4 receptor agonist ffectively induced ENCCs proliferation and differentiation.

  17. Cannabinoids: Medical implications.

    Science.gov (United States)

    Schrot, Richard J; Hubbard, John R

    2016-01-01

    Herbal cannabis has been used for thousands of years for medical purposes. With elucidation of the chemical structures of tetrahydrocannabinol (THC) and cannabidiol (CBD) and with discovery of the human endocannabinoid system, the medical usefulness of cannabinoids has been more intensively explored. While more randomized clinical trials are needed for some medical conditions, other medical disorders, like chronic cancer and neuropathic pain and certain symptoms of multiple sclerosis, have substantial evidence supporting cannabinoid efficacy. While herbal cannabis has not met rigorous FDA standards for medical approval, specific well-characterized cannabinoids have met those standards. Where medical cannabis is legal, patients typically see a physician who "certifies" that a benefit may result. Physicians must consider important patient selection criteria such as failure of standard medical treatment for a debilitating medical disorder. Medical cannabis patients must be informed about potential adverse effects, such as acute impairment of memory, coordination and judgment, and possible chronic effects, such as cannabis use disorder, cognitive impairment, and chronic bronchitis. In addition, social dysfunction may result at work/school, and there is increased possibility of motor vehicle accidents. Novel ways to manipulate the endocannbinoid system are being explored to maximize benefits of cannabinoid therapy and lessen possible harmful effects.

  18. What Are Synthetic Cannabinoids?

    Science.gov (United States)

    ... years, synthetic cannabinoid mixtures have been easy to buy in drug paraphernalia shops, novelty stores, gas stations, and over ... abuse, authorities have made it illegal to sell, buy, or possess some of ... use is that standard drug tests cannot easily detect many of the chemicals ...

  19. Role of 68Ga somatostatin receptor PET/CT in the detection of endogenous hyperinsulinaemic focus: an explorative study

    International Nuclear Information System (INIS)

    Prasad, Vikas; Sainz-Esteban, Aurora; Arsenic, Ruza; Ploeckinger, Ursula; Denecke, Timm; Pape, Ulrich-Frank; Pavel, Marianne; Pascher, Andreas; Kuehnen, Peter; Blankenstein, Oliver

    2016-01-01

    To explore the role of 68 Ga-DOTATATE/DOTATOC PET/CT (SR PET/CT) in patients with suspicion of or histopathologically proven pancreatogenic hyperinsulinaemic hypoglycaemia. We included 13 patients with histopathologically proven or a high clinical suspicion of pancreatogenic hyperinsulinaemia. All the patients underwent a SR PET/CT scan. The results were correlated with histopathological findings. Normalization of blood glucose levels after resection of the pancreatic lesion, as well as a cytological and/or pathological diagnosis of insulinoma, was considered the diagnostic gold standard for insulinoma. The diagnosis of nesidioblastosis was based on exclusion of an insulinoma and conclusive pathological examination of a segment of the pancreas. Malignant insulinoma was defined as the presence of locoregional or distant metastases. Based on histopathology, 13 patients were found to have pancreatic hyperinsulinaemia: two patients had malignant insulinoma, eight had nonmetastasized insulinoma, and three had nesidioblastosis. SR PET was positive in 11 of the 13 patients (84.6 %) with a final diagnosis of endogenous pancreatic hypoglycaemia. Histopathological staining confirmed 16 foci of hyperinsulinism (insulin positivity). SR PET detected 14 of the 16 lesions, resulting in a sensitivity of 87 %. One intrapancreatic spleen was falsely diagnosed as insulinoma focus on SR PET, resulting in positive predictive value of 93.3 %. Immunohistochemical staining of somatostatin receptor (SSR) subtype 2a was available in ten specimens: two nesidioblastosis, and seven benign and one malignant insulinoma. Eight out of the ten specimens (80 %) stained strongly to moderately positive. Seven of the eight SSR2a-positive lesions were picked up on SR PET. Based on the results of SR PET/CT, nine patients achieved complete remission of the hypoglycaemic events during follow-up. This explorative study suggests that SR PET in combination with CT may play a significant role in the detection

  20. Emerging Role of (EndoCannabinoids in Migraine

    Directory of Open Access Journals (Sweden)

    Pinja Leimuranta

    2018-04-01

    Full Text Available In this mini-review, we summarize recent discoveries and present new hypotheses on the role of cannabinoids in controlling trigeminal nociceptive system underlying migraine pain. Individual sections of this review cover key aspects of this topic, such as: (i the current knowledge on the endocannabinoid system (ECS with emphasis on expression of its components in migraine related structures; (ii distinguishing peripheral from central site of action of cannabinoids, (iii proposed mechanisms of migraine pain and control of nociceptive traffic by cannabinoids at the level of meninges and in brainstem, (iv therapeutic targeting in migraine of monoacylglycerol lipase and fatty acid amide hydrolase, enzymes which control the level of endocannabinoids; (v dual (possibly opposing actions of cannabinoids via anti-nociceptive CB1 and CB2 and pro-nociceptive TRPV1 receptors. We explore the cannabinoid-mediated mechanisms in the frame of the Clinical Endocannabinoid Deficiency (CECD hypothesis, which implies reduced tone of endocannabinoids in migraine patients. We further discuss the control of cortical excitability by cannabinoids via inhibition of cortical spreading depression (CSD underlying the migraine aura. Finally, we present our view on perspectives of Cannabis-derived (extracted or synthetized marijuana components or novel endocannabinoid therapeutics in migraine treatment.

  1. The maintenance of cisplatin- and paclitaxel-induced mechanical and cold allodynia is suppressed by cannabinoid CB2 receptor activation and independent of CXCR4 signaling in models of chemotherapy-induced peripheral neuropathy

    Directory of Open Access Journals (Sweden)

    Deng Liting

    2012-09-01

    Full Text Available Abstract Background Chemotherapeutic agents produce dose-limiting peripheral neuropathy through mechanisms that remain poorly understood. We previously showed that AM1710, a cannabilactone CB2 agonist, produces antinociception without producing central nervous system (CNS-associated side effects. The present study was conducted to examine the antinociceptive effect of AM1710 in rodent models of neuropathic pain evoked by diverse chemotherapeutic agents (cisplatin and paclitaxel. A secondary objective was to investigate the potential contribution of alpha-chemokine receptor (CXCR4 signaling to both chemotherapy-induced neuropathy and CB2 agonist efficacy. Results AM1710 (0.1, 1 or 5 mg/kg i.p. suppressed the maintenance of mechanical and cold allodynia in the cisplatin and paclitaxel models. Anti-allodynic effects of AM1710 were blocked by the CB2 antagonist AM630 (3 mg/kg i.p., but not the CB1 antagonist AM251 (3 mg/kg i.p., consistent with a CB2-mediated effect. By contrast, blockade of CXCR4 signaling with its receptor antagonist AMD3100 (10 mg/kg i.p. failed to attenuate mechanical or cold hypersensitivity induced by either cisplatin or paclitaxel. Moreover, blockade of CXCR4 signaling failed to alter the anti-allodynic effects of AM1710 in the paclitaxel model, further suggesting distinct mechanisms of action. Conclusions Our results indicate that activation of cannabinoid CB2 receptors by AM1710 suppresses both mechanical and cold allodynia in two distinct models of chemotherapy-induced neuropathic pain. By contrast, CXCR4 signaling does not contribute to the maintenance of chemotherapy-induced established neuropathy or efficacy of AM1710. Our studies suggest that CB2 receptors represent a promising therapeutic target for the treatment of toxic neuropathies produced by cisplatin and paclitaxel chemotherapeutic agents.

  2. Involvement of Cannabinoid Signaling in Vincristine-Induced Gastrointestinal Dysmotility in the Rat

    Science.gov (United States)

    Vera, Gema; López-Pérez, Ana E.; Uranga, José A.; Girón, Rocío; Martín-Fontelles, Ma Isabel; Abalo, Raquel

    2017-01-01

    Background: In different models of paralytic ileus, cannabinoid receptors are overexpressed and endogenous cannabinoids are massively released, contributing to gastrointestinal dysmotility. The antitumoral drug vincristine depresses gastrointestinal motility and a similar mechanism could participate in this effect. Therefore, our aim was to determine, using CB1 and CB2 antagonists, whether an increased endocannabinoid tone is involved in vincristine-induced gastrointestinal ileus. Methods: First, we confirmed the effects of vincristine on the gut mucosa, by conventional histological techniques, and characterized its effects on motility, by radiographic means. Conscious male Wistar rats received an intraperitoneal injection of vincristine (0.1–0.5 mg/kg), and barium sulfate (2.5 ml; 2 g/ml) was intragastrically administered 0, 24, or 48 h later. Serial X-rays were obtained at different time-points (0–8 h) after contrast. X-rays were used to build motility curves for each gastrointestinal region and determine the size of stomach and caecum. Tissue samples were taken for histology 48 h after saline or vincristine (0.5 mg/kg). Second, AM251 (a CB1 receptor antagonist) and AM630 (a CB2 receptor antagonist) were used to determine if CB1 and/or CB2 receptors are involved in vincristine-induced gastrointestinal dysmotility. Key results: Vincristine induced damage to the mucosa of ileum and colon and reduced gastrointestinal motor function at 0.5 mg/kg. The effect on motor function was particularly evident when the study started 24 h after administration. AM251, but not AM630, significantly prevented vincristine effect, particularly in the small intestine, when administered thrice. AM251 alone did not significantly alter gastrointestinal motility. Conclusions: The fact that AM251, but not AM630, is capable of reducing the effect of vincristine suggests that, like in other experimental models of paralytic ileus, an increased cannabinoid tone develops and is at least

  3. The antitumor activity of plant-derived non-psychoactive cannabinoids

    OpenAIRE

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

    2015-01-01

    As a therapeutic agent, most people are familiar with the palliative effects of the primary psychoactive constituent of Cannabis sativa (CS), Δ9-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 tha...

  4. [Cannabinoids in pain medicine].

    Science.gov (United States)

    Karst, M

    2018-06-07

    The endocannabinoid system (ECS) controls a large number of vital functions. Suboptimal tone of the ECS in certain regions of the nervous system may be associated with disorders that are also associated with pain. Pain and inflammation processes can be modulated by the exogenous supply of cannabinoids. Low-to-moderate pain-relieving effects and in individual cases large pain-relieving effects were observed in randomized, controlled studies of various types of chronic pain. People with chronic neuropathic pain and stress symptoms seem to particularly benefit. The therapeutic range of cannabinoids is small; often small doses are sufficient for clinically significant effects. The "Cannabis-als-Medizin-Gesetz" (cannabis as medicine law) allows the prescription of cannabis preparations under certain conditions. Available data indicate good long-term efficacy and tolerability. However, there is little systematic long-term experience from clinical studies.

  5. Endogenous protein and enzyme fragments induce immunoglobulin E-independent activation of mast cells via a G protein-coupled receptor, MRGPRX2.

    Science.gov (United States)

    Tatemoto, K; Nozaki, Y; Tsuda, R; Kaneko, S; Tomura, K; Furuno, M; Ogasawara, H; Edamura, K; Takagi, H; Iwamura, H; Noguchi, M; Naito, T

    2018-05-01

    Mast cells play a central role in inflammatory and allergic reactions by releasing inflammatory mediators through 2 main pathways, immunoglobulin E-dependent and E-independent activation. In the latter pathway, mast cells are activated by a diverse range of basic molecules (collectively known as basic secretagogues) through Mas-related G protein-coupled receptors (MRGPRs). In addition to the known basic secretagogues, here, we discovered several endogenous protein and enzyme fragments (such as chaperonin-10 fragment) that act as bioactive peptides and induce immunoglobulin E-independent mast cell activation via MRGPRX2 (previously known as MrgX2), leading to the degranulation of mast cells. We discuss the possibility that MRGPRX2 responds various as-yet-unidentified endogenous ligands that have specific characteristics, and propose that MRGPRX2 plays an important role in regulating inflammatory responses to endogenous harmful stimuli, such as protein breakdown products released from damaged or dying cells. © 2018 The Foundation for the Scandinavian Journal of Immunology.

  6. The tryptophan-derived endogenous arylhydrocarbon receptor ligand 6-formylindolo[3,2-b]carbazole (FICZ) is a nanomolar UVA-photosensitizer in epidermal keratinocytes

    Science.gov (United States)

    Williams, Joshua D.; Cabello, Christopher M.; Qiao, Shuxi; Wondrak, Georg T.

    2014-01-01

    Endogenous UVA-chromophores may act as sensitizers of oxidative stress underlying cutaneous photoaging and photocarcinogenesis, but the molecular identity of non-DNA key chromophores displaying UVA-driven photodyamic activity in human skin remains largely undefined. Here we report that 6-formylindolo[3,2-b]carbazole (FICZ), a tryptophan photoproduct and endogenous high affinity aryl hydrocarbon receptor (AhR) agonist, acts as a nanomolar photosensitizer potentiating UVA-induced oxidative stress irrespective of AhR ligand activity. In human HaCaT and primary epidermal keratinocytes, photodynamic induction of apoptosis was elicited by the combined action of solar simulated UVA and FICZ, whereas exposure to the isolated action of UVA or FICZ did not impair viability. In a human epidermal tissue reconstruct, FICZ/UVA-cotreatment caused pronounced phototoxicity inducing keratinocyte cell death, and FICZ photodynamic activity was also substantiated in a murine skin exposure model. Array analysis revealed pronounced potentiation of cellular heat shock, ER stress, and oxidative stress response gene expression observed only upon FICZ/UVA-cotreatment. FICZ photosensitization caused intracellular oxidative stress, and comet analysis revealed introduction of formamidopyrimidine-DNA glycosylase (FPG)-sensitive oxidative DNA lesions suppressible by antioxidant cotreatment. Taken together, our data demonstrate that the endogenous AhR ligand FICZ displays nanomolar photodynamic activity representing a molecular mechanism of UVA-induced photooxidative stress potentially operative in human skin. PMID:25431849

  7. Positive versus negative modulation of different endogenous chemokines for CC-chemokine receptor 1 by small molecule agonists through allosteric versus orthosteric binding

    DEFF Research Database (Denmark)

    Jensen, Pia C; Thiele, Stefanie; Ulven, Trond

    2008-01-01

    7 transmembrane-spanning (7TM) chemokine receptors having multiple endogenous ligands offer special opportunities to understand the molecular basis for allosteric mechanisms. Thus, CC-chemokine receptor 1 (CCR1) binds CC-chemokine 3 and 5 (CCL3 and CCL5) with K(d) values of 7.3 and 0.16 nm......5 and not CCL3 activation is affected by substitutions in the main ligand binding pocket including the conserved GluVII:06 anchor point. A series of metal ion chelator complexes were found to act as full agonists on CCR1 and to be critically affected by the same substitutions in the main ligand...... binding pocket as CCL5 but not by mutations in the extracellular domain. In agreement with the overlapping binding sites, the small non-peptide agonists displaced radiolabeled CCL5 with high affinity. Interestingly, the same compounds acted as allosteric enhancers of the binding of CCL3, with which...

  8. Mechanism of the Interaction of Cannabinoid System in Central Amygdale with Opioid System

    Directory of Open Access Journals (Sweden)

    S. Sarahroodi

    2008-01-01

    Full Text Available Background and objectivesCannabinoids which are active compounds of marijuana show some pharmacological effects similar to the opioids. There are also functional interactions between both cannabinoid and opioid systems. In this study we investigated the role of cannabinoid receptors in central amygdala and its interaction with opioid system.MethodsIn the present study, we investigated the effects of intraperitoneal injection of opioid drugs on response-induced by intra-amygdala (intra-Amyg microinjection of cannabinoid agents in rats, using elevated plus-maze test of anxiety. ResultsIntraperitoneal injection of morphine (3, 6 and 9 mg/kg increased %OAT and %OAE, but not locomotor activity, showing an anxiolytic response. However, some doses of the opioid receptor antagonist, naloxone reduced %OAT and locomotor activity as well. Intra-Amyg administration of CB1 cannabinoid receptor agonist, ACPA (at the dose of 1.25 and 5 ng/rat increased %OAT and %OAE but not locomotor activity, thus showing an anxiolytic response, which was increased by morphine (6 mg/kg, i.p. without any interaction. Naloxone also reduced ACPA effects. Intra-Amyg administration of CB1 cannabinoid receptor antagonist, AM251 (2.5, 25 and 100 ng/rat did not alter %OAT and %OAE but higher doses of drug (25 and 100 ng/rat reduced locomotor activity. However, the drug in combination of morphine anxiolytic response and with naloxone decreased anxiety.ConclusionThe results may indicate an anxiolytic for CB1 cannabinoid. Our results also showed that opioid system may have interaction with cannabinoid receptor in the amygdale. Keywords: Cannabinoids, Morphine; Naloxone, Anxiety, Elevated Plus-Maze

  9. Clinical pharmacology of cannabinoids in early phase drug development

    NARCIS (Netherlands)

    Zuurman, Hillie Henka

    2008-01-01

    Although cannabis is especially known for its recreational use as a ‘soft drug’, its potential therapeutic properties have been recognized for hundreds of years. Since the isolation of THC from Cannabis sativa L, the discovery of cannabinoid receptors and their natural ligands (endocannabinoids) the

  10. Endogenous acute phase serum amyloid A lacks pro-inflammatory activity, contrasting the two recombinant variants that activate human neutrophils through different receptors

    Directory of Open Access Journals (Sweden)

    Karin eChristenson

    2013-04-01

    Full Text Available Most notable among the acute phase proteins is serum amyloid A (SAA, levels of which can increase 1000-fold during infections, aseptic inflammation, and/or trauma. Chronically elevated SAA levels are associated with a wide variety of pathological conditions, including obesity and rheumatic diseases. Using a recombinant hybrid of the two human SAA isoforms (SAA1 and 2 that does not exist in vivo, numerous in vitro studies have given rise to the notion that acute phase SAA is a pro-inflammatory molecule with cytokine-like properties. It is however unclear whether endogenous acute phase SAA per se mediates pro-inflammatory effects. We tested this in samples from patients with inflammatory arthritis and in a transgenic mouse model that expresses human SAA1. Endogenous human SAA did not drive production of pro-inflammatory IL-8/KC in either of these settings. Human neutrophils derived from arthritis patients displayed no signs of activation, despite being exposed to severely elevated SAA levels in circulation, and SAA-rich sera also failed to activate cells in vitro. In contrast, two recombinant SAA variants (the hybrid SAA and SAA1 both activated human neutrophils, inducing L-selectin shedding, production of reactive oxygen species, and production of IL-8. The hybrid SAA was approximately 100-fold more potent than recombinant SAA1. Recombinant hybrid SAA and SAA1 activated neutrophils through different receptors, with recombinant SAA1 being a ligand for formyl peptide receptor 2 (FPR2. We conclude that even though recombinant SAAs can be valuable tools for studying neutrophil activation, they do not reflect the nature of the endogenous protein.

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

    Science.gov (United States)

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

    2016-06-01

    In order to investigate the in vivo dopamine (DA) stimulant properties of selected 3rd generation Spice/K2 cannabinoids, BB-22, 5F-PB-22, 5F-AKB-48 and STS-135, their in vitro affinity and agonist potency at native rat and mice CB1 receptors was studied. The compounds bind with high affinity to CB1 receptors in rat cerebral cortex homogenates and stimulate CB1-induced [(35)S]GTPγS binding with high potency and efficacy. BB-22 and 5F-PB-22 showed the lowest Ki of binding to CB1 receptors (0.11 and 0.13 nM), i.e., 30 and 26 times lower respectively than that of JWH-018 (3.38 nM), and a potency (EC50, 2.9 and 3.7 nM, respectively) and efficacy (Emax, 217% and 203%, respectively) as CB1 agonists higher than JWH-018 (EC50, 20.2 nM; Emax, 163%). 5F-AKB-48 and STS-135 had higher Ki for CB1 binding, higher EC50 and lower Emax as CB1 agonists than BB-22 and 5F-PB-22 but still comparatively more favourable than JWH-018. The agonist properties of all the compounds were abolished or drastically reduced by the CB1 antagonist/inverse agonist AM251 (0.1 μM). No activation of G-protein was observed in CB1-KO mice. BB-22 (0.003-0.01 mg/kg i.v.) increased dialysate DA in the accumbens shell but not in the core or in the medial prefrontal cortex, with a bell shaped dose-response curve and an effect at 0.01 mg/kg and a biphasic time-course. Systemic AM251 (1.0 mg/kg i.p.) completely prevented the stimulant effect of BB-22 on dialysate DA in the NAc shell. All the other compounds increased dialysate DA in the NAc shell at doses consistent with their in vitro affinity for CB1 receptors (5F-PB-22, 0.01 mg/kg; 5F-AKB-48, 0.1 mg/kg; STS-135, 0.15 mg/kg i.v.). 3rd generation cannabinoids can be even more potent and super-high CB1 receptor agonists compared to JWH-018. Future research will try to establish if these properties can explain the high toxicity and lethality associated with these compounds. Copyright © 2015 Elsevier Ltd. All rights reserved.

  12. Interaction of chemokine receptor CXCR4 in monomeric and dimeric state with its endogenous ligand CXCL12: coarse-grained simulations identify differences.

    Science.gov (United States)

    Cutolo, Pasquale; Basdevant, Nathalie; Bernadat, Guillaume; Bachelerie, Françoise; Ha-Duong, Tâp

    2017-02-01

    Despite the recent resolutions of the crystal structure of the chemokine receptor CXCR4 in complex with small antagonists or viral chemokine, a description at the molecular level of the interactions between the full-length CXCR4 and its endogenous ligand, the chemokine CXCL12, in relationship with the receptor recognition and activation, is not yet completely elucidated. Moreover, since CXCR4 is able to form dimers, the question of whether the CXCR4-CXCL12 complex has a 1:1 or 2:1 preferential stoichiometry is still an open question. We present here results of coarse-grained protein-protein docking and molecular dynamics simulations of CXCL12 in association with CXCR4 in monomeric and dimeric states. Our proposed models for the 1:1 and 2:1 CXCR4-CXCL12 quaternary structures are consistent with recognition and activation motifs of both partners provided by the available site-directed mutagenesis data. Notably, we observed that in the 2:1 complex, the chemokine N-terminus makes more steady contacts with the receptor residues critical for binding and activation than in the 1:1 structure, suggesting that the 2:1 stoichiometry would favor the receptor signaling activity with respect to the 1:1 association.

  13. [123I]Iodobenzamide binding to the rat dopamine D2 receptor in competition with haloperidol and endogenous dopamine - an in vivo imaging study with a dedicated small animal SPECT

    International Nuclear Information System (INIS)

    Nikolaus, Susanne; Larisch, Rolf; Wirrwar, Andreas; Jamdjeu-Noune, Marlyse; Antke, Christina; Beu, Markus; Mueller, Hans-Wilhelm; Schramm, Nils

    2005-01-01

    This study assessed [ 123 I]iodobenzamide binding to the rat dopamine D 2 receptor in competition with haloperidol and endogenous dopamine using a high-resolution small animal SPECT. Subsequent to baseline quantifications of D 2 receptor binding, imaging studies were performed on the same animals after pre-treatment with haloperidol and methylphenidate, which block D 2 receptors and dopamine transporters, respectively. Striatal baseline equilibrium ratios (V 3 '' ) of [ 123 I]iodobenzamide binding were 1.42±0.31 (mean±SD). After pre-treatment with haloperidol and methylphenidate, V 3 '' values decreased to 0.54±0.46 (p 123 I]iodobenzamide binding induced by pre-treatment with haloperidol reflects D 2 receptor blockade, whereas the decrease in receptor binding induced by pre-treatment with methylphenidate can be interpreted in terms of competition between [ 123 I]IBZM and endogenous dopamine. Findings show that multiple in vivo measurements of [ 123 I]iodobenzamide binding to D 2 receptors in competition with exogenous and endogenous ligands are feasible in the same animal. This may be of future relevance for the in vivo evaluation of novel radioligands as well as for studying the interrelations between pre- and/or postsynaptic radioligand binding and different levels of endogenous dopamine. (orig.)

  14. Polarized cellular patterns of endocannabinoid production and detection shape cannabinoid signaling in neurons

    Directory of Open Access Journals (Sweden)

    Delphine eLadarre

    2015-01-01

    Full Text Available Neurons display important differences in plasma membrane composition between somatodendritic and axonal compartments, potentially leading to currently unexplored consequences in G-protein-coupled-receptor signaling. Here, by using highly-resolved biosensor imaging to measure local changes in basal levels of key signaling components, we explored features of type-1 cannabinoid receptor (CB1R signaling in individual axons and dendrites of cultured rat hippocampal neurons. Activation of endogenous CB1Rs led to rapid, Gi/o-protein- and cAMP-mediated decrease of cyclic-AMP-dependent protein kinase (PKA activity in the somatodendritic compartment. In axons, PKA inhibition was significantly stronger, in line with axonally-polarized distribution of CB1Rs. Conversely, inverse agonist AM281 produced marked rapid increase of basal PKA activation in somata and dendrites, but not in axons, removing constitutive activation of CB1Rs generated by local production of the endocannabinoid 2-arachidonoylglycerol (2-AG. Interestingly, somatodendritic 2-AG levels differently modified signaling responses to CB1R activation by Δ9-THC, the psychoactive compound of marijuana, and by the synthetic cannabinoids WIN55,212-2 and CP55,940. These highly contrasted differences in sub-neuronal signaling responses warrant caution in extrapolating pharmacological profiles, which are typically obtained in non-polarized cells, to predict in vivo responses of axonal (i.e. presynaptic GPCRs. Therefore, our results suggest that enhanced comprehension of GPCR signaling constraints imposed by neuronal cell biology may improve the understanding of neuropharmacological action.

  15. Effect of Delta-tetrahydrocannabinol, a cannabinoid receptor agonist, on the triggering of transient lower oesophageal sphincter relaxations in dogs and humans

    NARCIS (Netherlands)

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

    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

  16. B cell recognition of the conserved HIV-1 co-receptor binding site is altered by endogenous primate CD4.

    Directory of Open Access Journals (Sweden)

    Mattias N E Forsell

    2008-10-01

    Full Text Available The surface HIV-1 exterior envelope glycoprotein, gp120, binds to CD4 on the target cell surface to induce the co-receptor binding site on gp120 as the initial step in the entry process. The binding site is comprised of a highly conserved region on the gp120 core, as well as elements of the third variable region (V3. Antibodies against the co-receptor binding site are abundantly elicited during natural infection of humans, but the mechanism of elicitation has remained undefined. In this study, we investigate the requirements for elicitation of co-receptor binding site antibodies by inoculating rabbits, monkeys and human-CD4 transgenic (huCD4 rabbits with envelope glycoprotein (Env trimers possessing high affinity for primate CD4. A cross-species comparison of the antibody responses showed that similar HIV-1 neutralization breadth was elicited by Env trimers in monkeys relative to wild-type (WT rabbits. In contrast, antibodies against the co-receptor site on gp120 were elicited only in monkeys and huCD4 rabbits, but not in the WT rabbits. This was supported by the detection of high-titer co-receptor antibodies in all sera from a set derived from human volunteers inoculated with recombinant gp120. These findings strongly suggest that complexes between Env and (high-affinity primate CD4 formed in vivo are responsible for the elicitation of the co-receptor-site-directed antibodies. They also imply that the naïve B cell receptor repertoire does not recognize the gp120 co-receptor site in the absence of CD4 and illustrate that conformational stabilization, imparted by primary receptor interaction, can alter the immunogenicity of a type 1 viral membrane protein.

  17. B cell recognition of the conserved HIV-1 co-receptor binding site is altered by endogenous primate CD4.

    Science.gov (United States)

    Forsell, Mattias N E; Dey, Barna; Mörner, Andreas; Svehla, Krisha; O'dell, Sijy; Högerkorp, Carl-Magnus; Voss, Gerald; Thorstensson, Rigmor; Shaw, George M; Mascola, John R; Karlsson Hedestam, Gunilla B; Wyatt, Richard T

    2008-10-03

    The surface HIV-1 exterior envelope glycoprotein, gp120, binds to CD4 on the target cell surface to induce the co-receptor binding site on gp120 as the initial step in the entry process. The binding site is comprised of a highly conserved region on the gp120 core, as well as elements of the third variable region (V3). Antibodies against the co-receptor binding site are abundantly elicited during natural infection of humans, but the mechanism of elicitation has remained undefined. In this study, we investigate the requirements for elicitation of co-receptor binding site antibodies by inoculating rabbits, monkeys and human-CD4 transgenic (huCD4) rabbits with envelope glycoprotein (Env) trimers possessing high affinity for primate CD4. A cross-species comparison of the antibody responses showed that similar HIV-1 neutralization breadth was elicited by Env trimers in monkeys relative to wild-type (WT) rabbits. In contrast, antibodies against the co-receptor site on gp120 were elicited only in monkeys and huCD4 rabbits, but not in the WT rabbits. This was supported by the detection of high-titer co-receptor antibodies in all sera from a set derived from human volunteers inoculated with recombinant gp120. These findings strongly suggest that complexes between Env and (high-affinity) primate CD4 formed in vivo are responsible for the elicitation of the co-receptor-site-directed antibodies. They also imply that the naïve B cell receptor repertoire does not recognize the gp120 co-receptor site in the absence of CD4 and illustrate that conformational stabilization, imparted by primary receptor interaction, can alter the immunogenicity of a type 1 viral membrane protein.

  18. Beyond THC: the new generation of cannabinoid designer drugs

    Directory of Open Access Journals (Sweden)

    Liana eFattore

    2011-09-01

    Full Text Available Synthetic cannabinoids are functionally similar to delta9-tetrahydrocannabinol (THC, the psychoactive principle of cannabis, and bind to the same cannabinoid receptors in the brain and peripheral organs. From 2008, synthetic cannabinoids were detected in herbal smoking mixtures sold on websites and in head shops under the brand name of Spice Gold, Yucatan Fire, Aroma, and others. Although these products (also known as Spice drugs or legal highs do not contain tobacco or cannabis, when smoked they produce effects similar to THC. Intoxication, withdrawal, psychosis and death have been recently reported after consumption, posing difficult social, political and health challenges. More than 140 different Spice products have been identified to date. The ability to induce strong cannabis-like psychoactive effects, along with the fact that they are readily available on the Internet, still legal in many countries, marketed as natural safe substances, and undetectable by conventional drug screening tests, has rendered these drugs very popular and particularly appealing to young and drug-naïve individuals seeking new experiences. An escalating number of compounds with cannabinoid receptor activity are currently being found as ingredients of Spice, of which almost nothing is known in terms of pharmacology, toxicology and safety. Since legislation started to control the synthetic cannabinoids identified in these herbal mixtures, many new analogs have appeared on the market. New cannabimimetic compounds are likely to be synthesized in the near future to replace banned synthetic cannabinoids, leading to a dog chasing its tail situation. Spice smokers are exposed to drugs that are extremely variable in composition and potency, and are at risk of serious, if not lethal, outcomes. Social and health professionals should maintain a high degree of alertness for Spice use and its possible psychiatric effects in vulnerable people.

  19. Characterisation of Signalling by the Endogenous GPER1 (GPR30 Receptor in an Embryonic Mouse Hippocampal Cell Line (mHippoE-18.

    Directory of Open Access Journals (Sweden)

    Nicholas J Evans

    Full Text Available Estrogen can modulate neuronal development and signalling by both genomic and non-genomic pathways. Many of its rapid, non-genomic effects on nervous tissue have been suggested to be mediated via the activation of the estrogen sensitive G-protein coupled receptor (GPER1 or GPR30. There has been much controversy over the cellular location, signalling properties and endogenous activators of GPER1. Here we describe the pharmacology and signalling properties of GPER1 in an immortalized embryonic hippocampal cell line, mHippoE-18. This cell line does not suffer from the inherent problems associated with the study of this receptor in native tissue or the problems associated with heterologously expression in clonal cell lines. In mHippoE-18 cells, 17β-Estradiol can mediate a dose-dependent rapid potentiation of forskolin-stimulated cyclic AMP levels but does not appear to activate the ERK1/2 pathway. The effect of 17β-Estradiol can be mimicked by the GPER1 agonist, G1, and also by tamoxifen and ICI 182,780 which activate GPER1 in a variety of other preparations. The response is not mimicked by the application of the classical estrogen receptor agonists, PPT, (an ERα agonist or DPN, (an ERβ agonist, further suggesting that this effect of 17β-Estradiol is mediated through the activation of GPER1. However, after exposure of the cells to the GPER1 specific antagonists, G15 and G36, the stimulatory effects of the above agonists are replaced by dose-dependent inhibitions of forskolin-stimulated cyclic AMP levels. This inhibitory effect is mimicked by aldosterone in a dose-dependent way even in the absence of the GPER1 antagonists. The results are discussed in terms of possible "Biased Antagonism" whereby the antagonists change the conformation of the receptor resulting in changes in the agonist induced coupling of the receptor to different second messenger pathways.

  20. γ-Preprotachykinin-(72-92)-peptide amide: An endogenous preprotachykinin I gene-derived peptide that preferentially binds to neurokinin-2 receptors

    International Nuclear Information System (INIS)

    Dam, T.V.; Takeda, Y.; Krause, J.E.; Escher, E.; Quirion, R.

    1990-01-01

    The presence of N-terminally extended forms of neurokinin A has recently been reported in the mammalian brain. Among them, gamma-preprotachykinin-(72-92)-peptide amide [gamma-PPT-(72-92)-NH2], a peptide derived by posttranslational processing of gamma-preprotachykinin, is most prominent. We report here that this peptide most likely acts on neurokinin-2 receptor sites since neurokinin A (a putative neurokinin-2 agonist) and gamma-PPT-(72-92)-NH2 are potent competitors of 125I-labeled gamma-PPT-(72-92)-NH2 binding whereas selective neurokinin-1 and -3 agonists are not. Moreover, the distribution of 125I-labeled gamma-PPT-(72-92)-NH2 and 125I-labeled neurokinin A binding sites are very similar in rat brain. On the other hand, 125I-labeled Bolton-Hunter-substance P (a neurokinin-1 ligand) and 125I-labeled Bolton-Hunter-eledoisin (a neurokinin-3 ligand) binding sites are differentially located in this tissue. Thus, it appears that gamma-PPT-(72-92)-NH2 binds to neurokinin-2 receptors and should be considered as a putative endogenous ligand for this receptor class

  1. IgM and IgD B cell receptors differentially respond to endogenous antigens and control B cell fate

    Science.gov (United States)

    Noviski, Mark; Mueller, James L; Satterthwaite, Anne; Garrett-Sinha, Lee Ann; Brombacher, Frank

    2018-01-01

    Naive B cells co-express two BCR isotypes, IgM and IgD, with identical antigen-binding domains but distinct constant regions. IgM but not IgD is downregulated on autoreactive B cells. Because these isotypes are presumed to be redundant, it is unknown how this could impose tolerance. We introduced the Nur77-eGFP reporter of BCR signaling into mice that express each BCR isotype alone. Despite signaling strongly in vitro, IgD is less sensitive than IgM to endogenous antigen in vivo and developmental fate decisions are skewed accordingly. IgD-only Lyn−/− B cells cannot generate autoantibodies and short-lived plasma cells (SLPCs) in vivo, a fate thought to be driven by intense BCR signaling induced by endogenous antigens. Similarly, IgD-only B cells generate normal germinal center, but impaired IgG1+ SLPC responses to T-dependent immunization. We propose a role for IgD in maintaining the quiescence of autoreactive B cells and restricting their differentiation into autoantibody secreting cells. PMID:29521626

  2. 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. Copyright © 2015 Elsevier Inc. All rights reserved.

  3. Endogenous antipyretics.

    Science.gov (United States)

    Roth, Joachim

    2006-09-01

    The febrile increase of body temperature is regarded as a component of the complex host response to infection or inflammation that accompanies the activation of the immune system. Late phases of fever appear mediated by pro-inflammatory cytokines called endogenous pyroge