DOCSLIB.ORG

Increased Seizure Susceptibility and Proconvulsant Activity of Anandamide in Mice Lacking Fatty Acid Amide Hydrolase

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Increased Seizure Susceptibility and Proconvulsant Activity of Anandamide in Mice Lacking Fatty Acid Amide Hydrolase 3916 • The Journal of Neuroscience, May 1, 2003 • 23(9):3916–3923 Increased Seizure Susceptibility and Proconvulsant Activity of Anandamide in Mice Lacking Fatty Acid Amide Hydrolase Angela B. Clement,1 E. Gregory Hawkins,1 Aron H. Lichtman,2 and Benjamin F. Cravatt1 1The Skaggs Institute for Chemical Biology and Departments of Cell Biology and Chemistry, The Scripps Research Institute, La Jolla, California 92037, and 2Department of Pharmacology and Toxicology, Medical College of Virginia Campus, Virginia Commonwealth University, Richmond, Virginia 23298 A number of recent in vitro studies have described a role for endogenous cannabinoids (“endocannabinoids”) as transsynaptic modu- lators of neuronal activity in the hippocampus and other brain regions. However, the impact that endocannabinoid signals may have on activity-dependent neural events in vivo remains mostly unknown and technically challenging to address because of the short half-life of these chemical messengers in the brain. Mice lacking the enzyme fatty acid amide hydrolase [FAAH (Ϫ/Ϫ) mice] are severely impaired in their ability to degrade the endocannabinoid anandamide and therefore represent a unique animal model in which to examine the function of this signaling lipid in vivo. Here, we show that the administration of anandamide dramatically augments the severity of chemically induced seizures in FAAH (Ϫ/Ϫ) mice but not in wild-type mice. Anandamide-enhanced seizures in FAAH (Ϫ/Ϫ) mice resulted in significant neuronal damage in the CA1 and CA3 regions of the hippocampus for the bicuculline and kainate models, respectively. Notably, in the absence of anandamide treatment, FAAH (Ϫ/Ϫ) mice exhibited enhanced seizure responses to high doses of kainate that correlated with greatly elevated endogenous levels of anandamide in the hippocampus of these animals. Collectively, these studies suggest that both exogenously administered and endogenously produced anandamide display FAAH-regulated proconvulsant activity and do not support a general neuroprotective role for this endocannabinoid in response to excitotoxic stimuli in vivo. More generally, these findings demonstrate that the disinhibitory actions of endocannabinoids observed in hippocampal slices in vitro may also occur in vivo. Keywords:anandamide;bicuculline;CB1 receptor;endocannabinoid;epilepsy;excitotoxicity;fattyacidamidehydrolase;kainate;seizure Introduction hippocampus, however, slice electrophysiological studies have The primary psychoactive ingredient of Cannabis sativa, ⌬ 9- provided evidence that endocannabinoids mediate a distinct tetrahydrocannabinol (THC), produces many neuropharmaco- form of transsynaptic communication referred to as logical effects in mammals primarily by activating a single “depolarization-induced suppression of inhibition” (Ohno- G-protein-coupled receptor CB1 (Ledent et al., 1999; Zimmer et Shosaku et al., 2001; Wilson and Nicoll, 2001). In this form of al., 1999). The broad distribution of the CB1 receptor in the CNS, retrograde transmission, endocannabinoids disinhibit pyramidal coupled with the identification of two natural CB1 ligands, neuron activity by suppressing neurotransmitter release from N-arachidonoyl ethanolamine (anandamide) (Devane et al., GABAergic interneurons (Katona et al., 1999), thus providing an 1992) and 2-arachidonoyl glycerol (2-AG) (Mechoulam et al., example in which the net effect of cannabinoids on neuronal 1995; Sugiura et al., 1995), has spurred considerable interest in firing is predicted to be stimulatory in vivo (Wilson and Nicoll, elucidating the function of the endogenous cannabinoid (“endo- 2002). However, the limited number of in vivo studies conducted cannabinoid”) system. Studies using CB1 agonists and antago- to date have not described a disinhibitory function for cannabi- Ϫ Ϫ nists, in combination with CB1 ( / ) mice, have indicated a role noids in the hippocampus. For example, THC was found to sup- for this receptor in modulating several behavioral processes, in- press the firing rates of hippocampal neurons in response to sen- cluding pain (Zimmer et al., 1999), feeding (Di Marzo et al., sory stimuli during a learning test (Hampson and Deadwyler, 2001), memory (Varvel and Lichtman, 2002), and locomotor 2000). These findings suggest that exocannabinoids and, by ex- activity (Zimmer et al., 1999). tension, endocannabinoids may produce rather complex and Many of the behavioral effects of cannabinoids could reflect even contradictory effects on neuronal activity in the hippocam- an inhibitory influence of these agents on neuronal firing in the pus, possibly depending on the distribution of the CB1 receptor CNS, as has been observed in the cerebellum (Kreitzer and Re- in the circuits under examination. Accordingly, how cannabi- gehr, 2001a) and nucleus accumbens (Pistis et al., 2002). In the noids impact pathological events related to excess hippocampal excitation, such as seizure and neurotoxicity, remains perplex- Received Oct. 22, 2002; revised Jan. 30, 2003; accepted Feb. 6, 2003. ingly difficult to predict. Indeed, although exocannabinoids are ThisworkwassupportedbyNationalInstituteofDrugAbuseoftheNationalInstitutesofHealthGrantsDA13173 generally considered to be anticonvulsant (Adams and Martin, and DA15197, Allergan, Inc., the Helen L. Dorris Institute for the Study of Neurological and Psychiatric Disorders of 1996), THC induces seizures in certain strains of rabbits (Martin ChildrenandAdolescents,andtheSkaggsInstituteforChemicalBiology.WethankTamasBartfai,FloydBloom,and and Consroe, 1976). the entire Cravatt group for helpful discussions and critical analysis of the work described in this manuscript. A major technical challenge facing the study of endocannabi- Correspondence should be addressed to Dr. Benjamin F. Cravatt, 10550 North Torrey Pines Road, La Jolla, CA 92037. E-mail: [email protected]. noids in vivo is their rapid rate of catabolism. For example, the Copyright © 2003 Society for Neuroscience 0270-6474/03/233916-08$15.00/0 half-life of anandamide in the rodent brain is less than a few Clement et al. • Anandamide Is Proconvulsant and Neurotoxic in FAAH (Ϫ/Ϫ) Mice J. Neurosci., May 1, 2003 • 23(9):3916–3923 • 3917 minutes (Willoughby et al., 1997), primarily attributable to hy- respectively). The organic layer was removed and dried under N2 gas. drolysis by the membrane-associated enzyme fatty acid amide The remaining residue was solubilized in methanol and injected onto an hydrolase (FAAH) (Cravatt et al., 1996). FAAH is broadly ex- Agilent (Palo Alto, CA) 1100 series LC-MS. Levels of endogenous anan- pressed throughout the CNS (Thomas et al., 1997), exhibiting a damide and OEA were quantified by comparing the mass ion peak heights with those of the corresponding d standards. PEA levels were complementary cellular distribution to CB receptors (Egertova 4 1 quantified by comparing the peak height of PEA with that of d -OEA [a et al., 1998; Tsou et al., 1998). Here, we took advantage of a mouse 4 d4-PEA internal standard could not be used because of overlapping re- model in which FAAH has been genetically deleted (Cravatt et al., tention times and masses with endogenous OEA (the mass of OEA equals 2001) to examine the role that anandamide plays in regulating the mass of the sodium adduct of d4-PEA)]. NAE levels were expressed as limbic seizures and hippocampal excitotoxicity in vivo. picomoles per gram of wet tissue Ϯ SEM. Statistical significance was determined with the unpaired t test. Materials and Methods Animals. FAAH (ϩ/ϩ) and FAAH (Ϫ/Ϫ) mice were generated by inter- crossing 129vJ–C57BL/6 FAAH (ϩ/Ϫ) mice as described previously Results (Cravatt et al., 2001). Studies were performed on littermate FAAH Anandamide exhibits proconvulsant activity in limbic seizure ϩ/ϩ) and FAAH (Ϫ/Ϫ) mice that had been backcrossed into the models in FAAH (؊/؊) mice) C57BL/6 strain for at least five generations to limit potential strain- The rapid rate at which anandamide is degraded in the brain dependent allelic variations that might contribute to behavioral and (Willoughby et al., 1997) has hindered experimental efforts to physiological differences. CB(ϩ/ϩ) and (Ϫ/Ϫ) mice were bred from study the function of this endocannabinoid in vivo. We recently CB(ϩ/Ϫ) mice backcrossed onto the C75BL/6 strain as described previ- described the generation and initial characterization of a mouse ously (Zimmer et al., 1999). All experiments were performed with mice model bearing a targeted disruption of the FAAH gene (FAAH from both genders, and no significant differences between female and (Ϫ/Ϫ) mice) (Cravatt et al., 2001). FAAH (Ϫ/Ϫ) mice are se- male mice were observed. Pharmacological agents. Anandamide, N-oleoyl ethanolamine (OEA), verely impaired in their ability to degrade anandamide and show and N-palmitoyl ethanolamine (PEA), synthesized as described previ- exaggerated CB1-dependent behavioral responses to this fatty ously (Cravatt et al., 1996), (R)-(ϩ)-WIN 55,212–2 (Sigma, St. Louis, acid amide. Additionally, brain levels of anandamide are in- MO), (S)-(Ϫ)-WIN 55,212–3 (Sigma), and SR141716A (kindly pro- creased Ͼ10-fold in FAAH (Ϫ/Ϫ) mice, a neurochemical pheno- vided by National Institute on Drug Abuse) were dissolved in ethanol type that correlates with enhanced CB1-dependent analgesia in and diluted in a final ratio of 1:1:18 in ethanol/Emulphor/saline. Kainate these animals. Interestingly, more recent studies have shown that (Ocean Produce International, Shelburne, Canada) was dissolved in sa- the hydrolytic rates of monoacylglycerols
Load more

Recommended publications
  • N-Acyl-Dopamines: Novel Synthetic CB1 Cannabinoid-Receptor Ligands
    Biochem. J. (2000) 351, 817–824 (Printed in Great Britain) 817 N-acyl-dopamines: novel synthetic CB1 cannabinoid-receptor ligands and inhibitors of anandamide inactivation with cannabimimetic activity in vitro and in vivo Tiziana BISOGNO*, Dominique MELCK*, Mikhail Yu. BOBROV†, Natalia M. GRETSKAYA†, Vladimir V. BEZUGLOV†, Luciano DE PETROCELLIS‡ and Vincenzo DI MARZO*1 *Istituto per la Chimica di Molecole di Interesse Biologico, C.N.R., Via Toiano 6, 80072 Arco Felice, Napoli, Italy, †Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, R. A. S., 16/10 Miklukho-Maklaya Str., 117871 Moscow GSP7, Russia, and ‡Istituto di Cibernetica, C.N.R., Via Toiano 6, 80072 Arco Felice, Napoli, Italy We reported previously that synthetic amides of polyunsaturated selectivity for the anandamide transporter over FAAH. AA-DA fatty acids with bioactive amines can result in substances that (0.1–10 µM) did not displace D1 and D2 dopamine-receptor interact with proteins of the endogenous cannabinoid system high-affinity ligands from rat brain membranes, thus suggesting (ECS). Here we synthesized a series of N-acyl-dopamines that this compound has little affinity for these receptors. AA-DA (NADAs) and studied their effects on the anandamide membrane was more potent and efficacious than anandamide as a CB" transporter, the anandamide amidohydrolase (fatty acid amide agonist, as assessed by measuring the stimulatory effect on intra- hydrolase, FAAH) and the two cannabinoid receptor subtypes, cellular Ca#+ mobilization in undifferentiated N18TG2 neuro- CB" and CB#. NADAs competitively inhibited FAAH from blastoma cells. This effect of AA-DA was counteracted by the l µ N18TG2 cells (IC&! 19–100 M), as well as the binding of the CB" antagonist SR141716A.
    [Show full text]
  • The Selective Reversible FAAH Inhibitor, SSR411298, Restores The
    www.nature.com/scientificreports OPEN The selective reversible FAAH inhibitor, SSR411298, restores the development of maladaptive Received: 22 September 2017 Accepted: 26 January 2018 behaviors to acute and chronic Published: xx xx xxxx stress in rodents Guy Griebel1, Jeanne Stemmelin2, Mati Lopez-Grancha3, Valérie Fauchey3, Franck Slowinski4, Philippe Pichat5, Gihad Dargazanli4, Ahmed Abouabdellah4, Caroline Cohen6 & Olivier E. Bergis7 Enhancing endogenous cannabinoid (eCB) signaling has been considered as a potential strategy for the treatment of stress-related conditions. Fatty acid amide hydrolase (FAAH) represents the primary degradation enzyme of the eCB anandamide (AEA), oleoylethanolamide (OEA) and palmitoylethanolamide (PEA). This study describes a potent reversible FAAH inhibitor, SSR411298. The drug acts as a selective inhibitor of FAAH, which potently increases hippocampal levels of AEA, OEA and PEA in mice. Despite elevating eCB levels, SSR411298 did not mimic the interoceptive state or produce the behavioral side-efects (memory defcit and motor impairment) evoked by direct-acting cannabinoids. When SSR411298 was tested in models of anxiety, it only exerted clear anxiolytic-like efects under highly aversive conditions following exposure to a traumatic event, such as in the mouse defense test battery and social defeat procedure. Results from experiments in models of depression showed that SSR411298 produced robust antidepressant-like activity in the rat forced-swimming test and in the mouse chronic mild stress model, restoring notably the development of inadequate coping responses to chronic stress. This preclinical profle positions SSR411298 as a promising drug candidate to treat diseases such as post-traumatic stress disorder, which involves the development of maladaptive behaviors. Te endocannabinoid (eCB) system is formed by two G protein-coupled receptors, CB1 and CB2, and their main transmitters, N-arachidonoylethanolamine (anandamide; AEA) and 2-arachidonoyglycerol (2-AG)1.
    [Show full text]
  • Trick Or Treat from Food Endocannabinoids?
    scientific correspondence 3. Casselman, J. M. in Proc. 1980 North Am. Eel Conf. (ed. Loftus, NAEs (0.01–5.8 mg per g) and oleamide of magnitude below those required, if K. H.) 74–82 (Ontario Ministry of Natural Resources, Ontario, (0.17–6.0 g per g), but no or very little administered by mouth, to reach the blood 1982). m 4. Radtke, R. L. Comp. Biochem. Physiol. A 92, 189–193 (1989). anandamide and no 2-AG. NAE levels are and cause observable ‘central’ effects. The 5. Kalish, J. M. J. Exp. Mar. Biol. Ecol. 132, 151–178 (1989). much lower in unfermented cocoa beans assays used here provide a gross evaluation of 6. Secor, D. H. Fish. Bull. US 90, 798–806 (1992). than in cocoa powder (which contained less cannabimimetic activity, and tests 7. Tzeng, W. N., Severin, K. P. & Wickström, H. Mar. Ecol. Prog. Ser. 149, 73–81 (1997). than 0.003 mg per g anandamide). Tiny monitoring more subtle behavioural changes 8. Angino, E. E., Billings, G. K. & Anderson, N. Chem. Geol. 1, amounts of anandamide in cocoa could that might be induced by low oral doses of 145–153 (1966). therefore be explained as artefacts of pro- NAEs/oleamide are needed before the rele- 9. Nakai, I., Iwata, R. & Tsukamoto, K. Spectrochim. Acta B (in the 2 cessing . Like all higher plants, cocoa plants vance of these compounds to the purported press). 8 10. Otake, T., Ishii, T., Nakahara, M. & Nakamura, R. Mar. Ecol. cannot synthesize arachidonic acid or its mild rewarding and craving-inducing effects 7 Prog.
    [Show full text]
  • Cannabis, the Endocannabinoid System and Immunity—The Journey from the Bedside to the Bench and Back
    International Journal of Molecular Sciences Review Cannabis, the Endocannabinoid System and Immunity—The Journey from the Bedside to the Bench and Back Osnat Almogi-Hazan * and Reuven Or Laboratory of Immunotherapy and Bone Marrow Transplantation, Hadassah Medical Center, The Faculty of Medicine, Hebrew University of Jerusalem, Jerusalem 91120, Israel; [email protected] * Correspondence: [email protected] Received: 21 May 2020; Accepted: 19 June 2020; Published: 23 June 2020 Abstract: The Cannabis plant contains numerous components, including cannabinoids and other active molecules. The phyto-cannabinoid activity is mediated by the endocannabinoid system. Cannabinoids affect the nervous system and play significant roles in the regulation of the immune system. While Cannabis is not yet registered as a drug, the potential of cannabinoid-based medicines for the treatment of various conditions has led many countries to authorize their clinical use. However, the data from basic and medical research dedicated to medical Cannabis is currently limited. A variety of pathological conditions involve dysregulation of the immune system. For example, in cancer, immune surveillance and cancer immuno-editing result in immune tolerance. On the other hand, in autoimmune diseases increased immune activity causes tissue damage. Immuno-modulating therapies can regulate the immune system and therefore the immune-regulatory properties of cannabinoids, suggest their use in the therapy of immune related disorders. In this contemporary review, we discuss the roles of the endocannabinoid system in immunity and explore the emerging data about the effects of cannabinoids on the immune response in different pathologies. In addition, we discuss the complexities of using cannabinoid-based treatments in each of these conditions.
    [Show full text]
  • Vegetal Marijuana, Animal Marijuana
    www.medigraphic.org.mx ACTUALIZACION POR TEMAS VEGETAL MARIJUANA, ANIMAL MARIJUANA Oscar Prospéro García*, Eric Murillo-Rodríguez*, Dolores Martínez González*, Mónica Méndez Díaz*, Javier Velázquez Moctezuma**, Luz Navarro* SUMMARY INTRODUCTION Marijuana is the illicit drug most commonly used worldwide. The Many drugs have the capacity to modify brain mechanisms by which this drug affects the brain have been studied physiology. In doing so, these psychoactive agents alter exhaustively during the last 40 years, and better understood in the last decade. For example, the discovery of receptors to which consciousness, alertness, perception and behavioral marijuana binds, has been a major achievement in neurosciences performance, and its repeated administration can often and in the study of drug addiction. Moreover, the description of the produce addiction due to their pharmacological effects. endogenous ligands, the endocannabinoids, has shed light to the In this review we discuss the action of marijuana and physiology of the brain regulating several behaviors: from pain to its receptors in the brain, and a group of fatty acid pleasure and from sex to thinking. ethanolamides that are naturally produced by vertebrate For all these exciting effects, endocannabinoids are an important and invertebrate Nervous Systems which bind to target for therapeutic endeavors. marijuana (cannabinoid) receptors. These molecules are Key words: Oleamide, anandamide, acylethanolamides, mating, the animal-produced marijuana: the endogenous feeding, sleeping. cannabinoids, all of which have an impact on conscious behavior and sleep. For centuries cannabinoids have been used for religious RESUMEN or mystical purposes, placing them in the type of drugs La mariguana es uno de los productos ilícitos de abuso que más se best described as “drugs of the spirit” (48).
    [Show full text]
  • Fatty Acid Amide Hydrolase: an Emerging Therapeutic Target in the Endocannabinoid System Benjamin F Cravatt and Aron H Lichtman
    469 Fatty acid amide hydrolase: an emerging therapeutic target in the endocannabinoid system Benjamin F Cravattà and Aron H Lichtman The medicinal properties of exogenous cannabinoids have been glycerol (2-AG) as a second endocannabinoid [5,6] has recognized for centuries and can largely be attributed to the fortified the hypothesis that cannabinoid (CB) receptors activation in the nervous system of a single G-protein-coupled are part of the sub-class of GPCRs that recognize lipids as receptor, CB1. However, the beneficial properties of their natural ligands. Consistent with this notion, based on cannabinoids, which include relief of pain and spasticity, are primary structural alignment of the GPCR superfamily, counterbalanced by adverse effects such as cognitive and motor CB receptors are most homologous to the edg receptors, dysfunction. The recent discoveries of anandamide, a natural which also bind endogenous lipids such as lysophospha- lipid ligand for CB1, and an enzyme, fatty acid amide hydrolase tidic acid and sphingosine 1-phosphate [7]. (FAAH), that terminates anandamide signaling have inspired pharmacological strategies to augment endogenous The identification of anandamide and 2-AG as endocan- cannabinoid (‘endocannabinoid’) activity with FAAH inhibitors, nabinoids has stimulated efforts to understand the which might exhibit superior selectivity in their elicited behavioral mechanisms for their biosynthesis and inactivation. Both effects compared with direct CB1 agonists. anandamide and 2-AG belong to large classes of natural
    [Show full text]
  • Regulation of Inflammatory Pain by Inhibition of Fatty Acid Amide Hydrolase□S
    0022-3565/10/3341-182–190$20.00 THE JOURNAL OF PHARMACOLOGY AND EXPERIMENTAL THERAPEUTICS Vol. 334, No. 1 Copyright © 2010 by The American Society for Pharmacology and Experimental Therapeutics 164806/3596864 JPET 334:182–190, 2010 Printed in U.S.A. Regulation of Inflammatory Pain by Inhibition of Fatty Acid Amide Hydrolase□S Pattipati S. Naidu, Steven G. Kinsey, Tai L. Guo, Benjamin F. Cravatt, and Aron H. Lichtman Department of Pharmacology and Toxicology, Medical College of Virginia Campus, Virginia Commonwealth University, Richmond, Virginia (P.S.N., S.G.K., T.L.G., A.H.L.); and The Skaggs Institute for Chemical Biology and Departments of Cell Biology and Chemical Physiology, The Scripps Research Institute, La Jolla, California (B.F.C.) Received December 14, 2009; accepted April 5, 2010 ABSTRACT Although cannabinoids are efficacious in laboratory animal models of 1,3,3-trimethyl bicyclo [2.2.1] heptan-2-yl]-5-(4-chloro-3-methylphe- inflammatory pain, their established cannabimimetic actions diminish nyl)-1-(4-methylbenzyl)-pyrazole-3-carboxamide] blocked this non- enthusiasm for their therapeutic development. Conversely, fatty acid neuronal, anti-inflammatory phenotype, and the CB1 cannabinoid amide hydrolase (FAAH), the chief catabolic enzyme regulating the receptor (CB1) antagonist rimonabant [SR141716, N-(piperidin-1-yl)- endogenous cannabinoid N-arachidonoylethanolamine (anand- 5-(4-chlorophenyl)-1-(2,4-dichlorophenyl)-4-methyl-1H-pyrazole-3- amide), has emerged as an attractive target for treating pain and other carboxamide] blocked the antihyperalgesic phenotype. The FAAH conditions. Here, we tested WIN 55212-2 [(R)-(ϩ)-[2,3-dihydro-5- inhibitor URB597 [cyclohexylcarbamic acid 3Ј-carbamoylbiphenyl- methyl-3-(4-morpholinylmethyl)pyrrolo[1,2,3-de)-1,4-benzoxazin-6- 3-yl ester] attenuated the development of LPS-induced paw edema yl]-1-napthalenylmethanone], a cannabinoid receptor agonist, and and reversed LPS-induced hyperalgesia through the respective CB2 genetic deletion or pharmacological inhibition of FAAH in the lipo- and CB1 mechanisms of action.
    [Show full text]
  • Comparison of Candida Albicans Fatty Acid Amide Hydrolase Structure with Homologous Amidase Signature Family Enzymes
    crystals Article Comparison of Candida Albicans Fatty Acid Amide Hydrolase Structure with Homologous Amidase Signature Family Enzymes 1, 1, 2 1,2 3 Cho-Ah Min y, Ji-Sook Yun y, Eun Hwa Choi , Ui Wook Hwang , Dong-Hyung Cho , Je-Hyun Yoon 4 and Jeong Ho Chang 1,2,* 1 Department of Biology Education, Kyungpook National University, Daegu 41566, Korea 2 Research Institute for Phylogenomics and Evolution, Kyungpook National University, Daegu 41566, Korea 3 School of Life Sciences, Kyungpook National University, Daegu 41566, Korea 4 Department of Biochemistry and Molecular Biology, Medical University of South Carolina, Charleston, SC 29425, USA * Correspondence: [email protected]; Tel.: +82-53-950-5913 These authors contributed equally to this work. y Received: 23 August 2019; Accepted: 8 September 2019; Published: 10 September 2019 Abstract: Fatty acid amide hydrolase (FAAH) is a well-characterized member of the amidase signature (AS) family of serine hydrolases. The membrane-bound FAAH protein is responsible for the catabolism of neuromodulatory fatty acid amides, including anandamide and oleamide, that regulate a wide range of mammalian behaviors, including pain perception, inflammation, sleep, and cognitive/emotional state. To date, limited crystal structures of FAAH and non-mammalian AS family proteins have been determined and used for structure-based inhibitor design. In order to provide broader structural information, the crystal structure of FAAH from the pathogenic fungus Candida albicans was determined at a resolution of 2.2 Å. A structural comparison with a brown rat Rattus norvegicus FAAH as well as with other bacterial AS family members, MAE2 and PAM, showed overall similarities but there were several discriminative regions found: the transmembrane domain and the hydrophobic cap of the brown rat FAAH were completely absent in the fungal FAAH structure.
    [Show full text]
  • Spice Overview
    SPICE OVERVIEW: There are numerous smokable herbal mixtures which have been marketed under the brand name of Spice since 2004 including Spice Gold, Spice Diamond, Spice Silver, Spice Artic Energy, Black Mamba, etc. These products and many other herbal preparations have been sold over the Internet and in specialized shops throughout the world. Although these herbal mixtures have been advertised as incense or bath salts and labeled “not for human consumption”, when smoked Spice products reportedly have similar effects to cannabis. Most of the labels on the Spice packages list a variety of potentially psychoactive plants such as Indian Warrior, Lion’s Tail, White and Blue Water Lily, and Dwarf Skullcap. These plants have traditionally been known as marijuana substitutes; therefore, users could expect similar effects to that of smoked cannabis. In 2008, forensic investigations were undertaken by the German and Austrian governments to identify the psychoactive ingredients in Spice. It was determined that the psychoactive effects of Spice were due to added synthetic cannabinoids rather than the herbal plants. The investigations identified JWH-018 a synthetic cannabinoid receptor (CB) agonist as the active ingredient in Spice. Although the chemical structure of JWH-018 differs significantly from THC (the psychoactive ingredient in marijuana), it produces similar effects and has been reported to be more potent than THC. Subsequent investigations in 2009, identified another synthetic cannabinoid, CP- 47,497. Later in 2009, the United States Drug Enforcement Administration (DEA) reported that another potent synthetic cannabinoid, HU-210 had been identified. Since 2008, several other synthetic cannabinoids including JWH-073, JWH-398, and HU-210 have been identified.
    [Show full text]
  • Spice’ Phenomenon 1
    ISSN 1725-5767 Understanding the ‘Spice’ phenomenon 1 Understanding the ‘Spice’ phenomenon PAPERS THEMATIC Understanding the ‘Spice’ phenomenon emcdda.europa.eu Contents Overview 3 1. Introduction and background 6 2. Herbal components of ‘Spice’ products 8 3. Synthetic cannabinoids receptor agonists: a brief chemical overview 9 4. Forensic identification, pharmacology and toxicology of synthetic cannabinoids 11 5. EMCDDA survey 13 6. Internet information 18 7. Control measures 19 8. Conclusions 21 Acknowledgements 24 References 25 Annex 1. Δ9-THC and six synthetic cannabinoids with high affinity for cannabinoid (CB1) receptors found in ‘Spice’ products 28 Annex 2. List of additional names and national websites collected through the questionnaire on ‘Spice’ products 29 Annex 3. Selected scientific articles 31 Understanding the ‘Spice’ phenomenon 3 emcdda.europa.eu Overview Smokable herbal mixtures under the brand name ‘Spice’ are known to have been sold on the Internet and in various specialised shops since at least 2006 and metadata reports (Google Insights web searches) suggest that those products may have been available as early as 2004. Although advertised as an ‘exotic incense blend which releases a rich aroma’ and ‘not for human consumption’, when smoked, ‘Spice’ products have been reported by some users to have effects similar to those of cannabis. There are a number of products marketed under the ‘Spice’ brand — these include, but are not limited to: Spice Silver, Spice Gold, Spice Diamond, Spice Arctic Synergy, Spice Tropical Synergy, Spice Egypt, etc. In addition, there are many other herbal preparations for which the claim is made that they have a similar make-up to ‘Spice’ — e.g.
    [Show full text]
  • New Approaches and Challenges to Targeting the Endocannabinoid
    PERSPECTIVES G protein‑coupled receptors (GPCRs) — OPINION cannabinoid receptor 1 (CB1) and CB2 (REFS7,8) — and that CB1 is responsible New approaches and challenges for the psychoactive effects of marijuana5,6,9. However, to date, no specific receptor for CBD has been identified. Several different to targeting the endocannabinoid molecular targets have been suggested to mediate distinct pharmacological effects of system this cannabinoid. The identification of CB1 and CB2 led Vincenzo Di Marzo to the isolation and characterization of endogenous ligands for these proteins, Abstract | The endocannabinoid signalling system was discovered because N‑arachidonoyl‑ethanolamine (AEA) receptors in this system are the targets of compounds present in psychotropic and 2‑arachidonoylglycerol (2‑AG)10–12 preparations of Cannabis sativa. The search for new therapeutics that target (FIG. 1), which were named the endo‑ endocannabinoid signalling is both challenging and potentially rewarding, as cannabinoids13, and of five main enzymes endocannabinoids are implicated in numerous physiological and pathological for their biosynthesis and inactivation: N‑acyl‑phosphatidylethanolamine‑ processes. Hundreds of mediators chemically related to the endocannabinoids, hydrolysing phospholipase D (NAPE‑PLD), often with similar metabolic pathways but different targets, have complicated the sn‑1‑specific diacylglycerol lipase‑α (DGLα), development of inhibitors of endocannabinoid metabolic enzymes but have also DGLβ, fatty acid amide hydrolase 1 (FAAH) stimulated the rational design of multi-target drugs. Meanwhile, drugs based on and monoacylglycerol lipase (MAGL; also 14–17 botanical cannabinoids have come to the clinical forefront, synthetic agonists known as MGL) . This system of two designed to bind cannabinoid receptor 1 with very high affinity have become a signalling lipids, their two receptors and their metabolic enzymes became known as societal threat and the gut microbiome has been found to signal in part through the endocannabinoid system and was soon the endocannabinoid network.
    [Show full text]
  • The Hypnotic Actions of the Fatty Acid Amide, Oleamide Wallace B
    The Hypnotic Actions of the Fatty Acid Amide, Oleamide Wallace B. Mendelson, M.D., and Anthony S. Basile, Ph.D. Oleamide is an endogenous fatty acid amide which can be pathways, as evidenced by the ability of the cannabinoid synthesized de novo in the mammalian nervous system, and antagonist SR 141716 to inhibit the hypnotic actions of has been detected in human plasma. It accumulates in the OA. Nonetheless, enhancement of cannabinergic function CSF of rats after six hours of sleep deprivation and induces may not be the only mechanism by which OA alters sleep, sleep in naive rats and mice. Inhibition of the primary as it can act synergistically with subthreshold doses of catabolic enzyme of oleamide (fatty acid amide hydrolase) by triazolam (0.125 ␮g) to reduce sleep latency. These findings trifluoromethyl-octadecenone reduces sleep latency and raise the possibility that OA may be representative of a increases total sleep time when given centrally to rats and group of compounds which might be developed into peripherally to mice. While the mechanism of action of clinically-used hypnotics, and are discussed in the context oleamide is unclear, it has been demonstrated to increase the of fatty acid derivatives as modulators of neuronal function. amplitude of currents gated by 5-HT2a, 5HT2c and [Neuropsychopharmacology 25:S36–S39, 2001] GABAa receptors. Moreover, the action of oleamide most © 2001 American College of Neuropsychopharmacology. relevant to sleep induction involves, in part, cannabinergic Published by Elsevier Science Inc. KEY WORDS: Oleamide; Fatty acids; Sleep; Hypnotics PHARMACOLOGY OF OLEAMIDE This review will describe the pharmacology of the un- There has been longstanding interest in long chain, saturated fatty acid amide oleamide (OA), presenting polyunsaturated free fatty acids as modulators of neu- data indicating that this substance is formed in the rotransmitter and voltage-gated ion channel activity mammalian CNS and has significant sleep-inducing (Meves 1994).
    [Show full text]