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Bahi A. Serotonin transporter knockdown relieves depression-like behavior and ethanol-induced CPP in mice after chronic social defeat stress. Behav Brain Res 2024; 466:114998. [PMID: 38614210 DOI: 10.1016/j.bbr.2024.114998] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2024] [Revised: 04/09/2024] [Accepted: 04/09/2024] [Indexed: 04/15/2024]
Abstract
Patients with stress-triggered major depression disorders (MDD) can often seek comfort or temporary relief through alcohol consumption, as they may turn to it as a means of self-medication or coping with overwhelming emotions. The use of alcohol as a coping mechanism for stressful events can escalate, fostering a cycle where the temporary relief it provides from depression can deepen into alcohol dependence, exacerbating both conditions. Although, the specific mechanisms involved in stress-triggered alcohol dependence and MDD comorbidities are not well understood, a large body of literature suggests that the serotonin transporter (SERT) plays a critical role in these abnormalities. To further investigate this hypothesis, we used a lentiviral-mediated knockdown approach to examine the role of hippocampal SERT knockdown in social defeat stress-elicited depression like behavior and ethanol-induced place preference (CPP). The results showed that social defeat stress-pro depressant effects were reversed following SERT knockdown demonstrated by increased sucrose preference, shorter latency to feed in the novelty suppressed feeding test, and decreased immobility time in the tail suspension and forced swim tests. Moreover, and most importantly, social stress-induced ethanol-CPP acquisition and reinstatement were significantly reduced following hippocampal SERT knockdown using short hairpin RNA shRNA-expressing lentiviral vectors. Finally, we confirmed that SERT hippocampal mRNA expression correlated with measures of depression- and ethanol-related behaviors by Pearson's correlation analysis. Taken together, our data suggest that hippocampal serotoninergic system is involved in social stress-triggered mood disorders as well as in the acquisition and retrieval of ethanol contextual memory and that blockade of this transporter can decrease ethanol rewarding properties.
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Affiliation(s)
- Amine Bahi
- College of Medicine, Ajman University, Ajman, United Arab Emirates; Center of Medical and Bio-Allied Health Sciences Research, Ajman University, Ajman, United Arab Emirates; Department of Anatomy, CMHS, UAE University, Al Ain, United Arab Emirates.
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De Sa Nogueira D, Bourdy R, Filliol D, Quessada C, McCort-Tranchepain I, Acher F, Zwiller J, Romieu P, Befort K. LSP2-9166, an orthosteric mGlu4 and mGlu7 receptor agonist, reduces cocaine self-administration under a progressive ratio schedule in rats. Neurosci Lett 2020; 764:135603. [PMID: 33387661 DOI: 10.1016/j.neulet.2020.135603] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2020] [Revised: 12/18/2020] [Accepted: 12/23/2020] [Indexed: 11/24/2022]
Abstract
Cocaine addiction is a serious health issue in Western countries. Despite the regular increase in cocaine consumption across the population, there is no specific treatment for cocaine addiction. Critical roles for glutamate neurotransmission in the rewarding effects of psychostimulants as well as relapse have been suggested and accumulating evidence indicates that targeting mGlu group III receptors could represent a promising strategy to develop therapeutic compounds to treat addiction. In this context, the aim of our study was to examine the effect of LSP2-9166, a mGlu4/mGlu7 receptor orthosteric agonist, on the motivation for cocaine intake. We used an intravenous self-administration paradigm in male Wistar rats as a reliable model of voluntary drug intake. We first evaluated the direct impact of cocaine on Grm4 and Grm7 gene expression. Voluntary cocaine intake under a fixed ratio schedule of injections induced an increase of both mGlu4 and mGlu7 receptor transcripts in nucleus accumbens and hippocampus. We then evaluated the ability of LSP2-9166 to affect cocaine self-administration under a progressive ratio schedule of reinforcement. We found that this compound inhibits the motivation to obtain the drug, although it induced a hypolocomotor effect which could biais motivation index. Our findings demonstrate that mGlu group III receptors represent new targets for decreasing motivation to self-administer cocaine.
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Affiliation(s)
- David De Sa Nogueira
- Université de Strasbourg, Laboratoire de Neurosciences Cognitives et Adaptatives (LNCA), Faculté de Psychologie, UMR 7364, CNRS 12 rue Goethe, F-67000, Strasbourg, France
| | - Romain Bourdy
- Université de Strasbourg, Laboratoire de Neurosciences Cognitives et Adaptatives (LNCA), Faculté de Psychologie, UMR 7364, CNRS 12 rue Goethe, F-67000, Strasbourg, France
| | - Dominique Filliol
- Université de Strasbourg, Laboratoire de Neurosciences Cognitives et Adaptatives (LNCA), Faculté de Psychologie, UMR 7364, CNRS 12 rue Goethe, F-67000, Strasbourg, France
| | - Cyril Quessada
- Université de Strasbourg, Laboratoire de Neurosciences Cognitives et Adaptatives (LNCA), Faculté de Psychologie, UMR 7364, CNRS 12 rue Goethe, F-67000, Strasbourg, France; Université de Strasbourg, Inserm, UMR-S1118, 11 rue Humann, F-67000, Strasbourg, France
| | - Isabelle McCort-Tranchepain
- Laboratoire de Chimie et Biochimie Pharmacologiques et Toxicologiques, CNRS UMR8601, Université de Paris 45 rue des Saints-Pères, F-75270, Paris Cedex 6, France
| | - Francine Acher
- Laboratoire de Chimie et Biochimie Pharmacologiques et Toxicologiques, CNRS UMR8601, Université de Paris 45 rue des Saints-Pères, F-75270, Paris Cedex 6, France
| | - Jean Zwiller
- Université de Strasbourg, Laboratoire de Neurosciences Cognitives et Adaptatives (LNCA), Faculté de Psychologie, UMR 7364, CNRS 12 rue Goethe, F-67000, Strasbourg, France
| | - Pascal Romieu
- Université de Strasbourg, Laboratoire de Neurosciences Cognitives et Adaptatives (LNCA), Faculté de Psychologie, UMR 7364, CNRS 12 rue Goethe, F-67000, Strasbourg, France
| | - Katia Befort
- Université de Strasbourg, Laboratoire de Neurosciences Cognitives et Adaptatives (LNCA), Faculté de Psychologie, UMR 7364, CNRS 12 rue Goethe, F-67000, Strasbourg, France.
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Effects of N-acetylcysteine treatment on ethanol's rewarding properties and dopaminergic alterations in mesocorticolimbic and nigrostriatal pathways. Behav Pharmacol 2020; 32:239-250. [PMID: 33290342 DOI: 10.1097/fbp.0000000000000613] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Recent reports have shown that N-acetylcysteine (N-AC) has beneficial effects in the treatment of cocaine and nicotine abuse. Considering the similar neurobiologic mechanisms involved in the development of addiction to different drugs, N-AC treatment could be useful in the treatment of ethanol abuse. The rewarding properties of the drugs of abuse plays an important role in the development of addiction and can be studied using the conditioned place preference (CPP) paradigm. Thus, to study the effects of N-AC treatment in the rewarding effects of ethanol, we investigated the effects of N-AC administration in the ethanol-induced CPP and neurochemical alterations within the mesocorticolimbic and the nigrostriatal dopaminergic pathways. Adult male Swiss mice were pretreated with N-AC (60 or 120 mg/kg intraperitoneal) and tested for the development, expression, or extinction of the ethanol-induced CPP. Another cohort of animals received N-AC (60 or 120 mg/kg intraperitoneal) 2-h before an acute administration of ethanol and had their brains removed for dopamine and its metabolites quantification in the mesocorticolimbic and nigrostriatal pathways. Pretreatment with N-AC (120 mg/kg) blocked the development of ethanol-induced CPP. On the other hand, N-AC at both doses did not alter the expression nor the extinction of ethanol-induced CPP. N-AC increased 3,4-dihydroxyphenylacetic acid content in the medial prefrontal cortex and dopaminergic turnover within the substantia nigra. Besides that, there was an increase in dopamine content in the nucleus accumbens of ethanol-treated animals. In summary, N-AC treatment blocked the development of ethanol CPP, without altering ethanol effects on dopaminergic neurotransmission.
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Vadasz C, Gyetvai BM. Cocaine-Induced Sensitization is Linked to Distal Chromosome 6 Region in Congenic Mouse Model. Drug Alcohol Depend 2020; 215:108185. [PMID: 32768991 PMCID: PMC7502495 DOI: 10.1016/j.drugalcdep.2020.108185] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/03/2020] [Revised: 06/23/2020] [Accepted: 07/13/2020] [Indexed: 01/05/2023]
Abstract
OBJECTIVE Previously we mapped QTL Eac2 to mouse Chr6 and identified the first gene (Grm7) as accounting for alcohol consumption in a mammalian model. Despite the central role of glutamate receptors in addiction, the effects of Grm7 gene variants are not well known. Here we test the hypothesis that genetic variation of the distal mouse Chr6 Eac2 region, location of Grm7, controls cocaine-induced locomotor sensitization. METHOD C57BL/6By background and B6.C6.327.54 congenic mice were subjected to whole-genome SNP genotyping. Isogeneic (C57BL/6ByXB6.C6.327.54)F2 mice homozygous for SNPs in the BALB/c-type Eac2 region were selected to create a subcongenic strain (B6By.C6.108-120). In a 2-strain x 2-sex 2-treatment factorial design (n = 6-10) C57BL/6By and B6By.C6.108-120 mice received repeated daily cocaine or saline intraperitoneal injections, and locomotor activity was recorded for 90 minutes immediately after injection. RESULTS C57BL/6By females with the G/G genotype of SNP rs3723352 of Grm7 responded to cocaine with significantly higher activity and greater cocaine-induced sensitization than those with the BALB/cJ-type T/T genotype in the congenic strain. CONCLUSION The results are consistent with a large body of accumulated mechanistic evidence for a role of the mGlu7 receptor in the control of neurobiological responses to cocaine, and are consistent with the hypotheses that (1) natural variants of the Grm7 gene show pleiotropy and can modulate cocaine-induced behaviors in addition to alcohol consumption, (2) interactions between mGluR7 expression, estrogen receptors, and estradiol may explain phenotypic variation in females. Heritable variation of GRM7 may affect vulnerability to substance abuse in women.
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Affiliation(s)
- Csaba Vadasz
- Laboratory of Neurobehavior Genetics, Nathan S. Kline Institute for Psychiatric Research 140 Old Orangeburg Rd., 10962, Orangeburg, NY, USA; Department of Psychiatry, New York University Langone Medical Center, New York, NY, USA.
| | - Beatrix M. Gyetvai
- Laboratory of Neurobehavior Genetics, Nathan S. Kline Institute for Psychiatric Research 140 Old Orangeburg Rd., 10962, Orangeburg, NY, USA
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Johnson KA, Lovinger DM. Allosteric modulation of metabotropic glutamate receptors in alcohol use disorder: Insights from preclinical investigations. ADVANCES IN PHARMACOLOGY (SAN DIEGO, CALIF.) 2020; 88:193-232. [PMID: 32416868 DOI: 10.1016/bs.apha.2020.02.002] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Metabotropic glutamate (mGlu) receptors are family C G protein-coupled receptors (GPCRs) that modulate neuronal excitability and synaptic transmission throughout the nervous system. Owing to recent advances in development of subtype-selective allosteric modulators of mGlu receptors, individual members of the mGlu receptor family have been proposed as targets for treating a variety of neurological and psychiatric disorders, including substance use disorders. In this chapter, we highlight preclinical evidence that allosteric modulators of mGlu receptors could be useful for reducing alcohol consumption and preventing relapse in alcohol use disorder (AUD). We begin with an overview of the preclinical models that are used to study mGlu receptor involvement in alcohol-related behaviors. Alcohol exposure causes adaptations in both expression and function of various mGlu receptor subtypes, and pharmacotherapies aimed at reversing these adaptations have the potential to reduce alcohol consumption and seeking. Positive allosteric modulators (PAMs) of mGlu2 and negative allosteric modulators of mGlu5 show particular promise for reducing alcohol intake and/or preventing relapse. Finally, this chapter discusses important considerations for translating preclinical findings toward the development of clinically useful drugs, including the potential for PAMs to avoid tolerance issues that are frequently observed with repeated administration of GPCR agonists.
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Affiliation(s)
- Kari A Johnson
- Department of Pharmacology, Uniformed Services University of the Health Sciences, Bethesda, MD, United States.
| | - David M Lovinger
- Laboratory for Integrative Neuroscience, National Institute on Alcohol Abuse and Alcoholism, US National Institutes of Health, Rockville, MD, United States
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Bahi A, Dreyer JL. Environmental enrichment decreases chronic psychosocial stress-impaired extinction and reinstatement of ethanol conditioned place preference in C57BL/6 male mice. Psychopharmacology (Berl) 2020; 237:707-721. [PMID: 31786650 DOI: 10.1007/s00213-019-05408-8] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/12/2019] [Accepted: 11/18/2019] [Indexed: 12/27/2022]
Abstract
RATIONALE During the last few decades, alcohol use disorders (AUD) have reached an epidemic prevalence, yet social influences on alcoholism have not been fully addressed. Several factors can modulate alcohol intake. On one hand, stress can reinforce ethanol-induced behaviors and be an important component in AUD and alcoholism. On the other hand, environmental enrichment (EE) has a neuroprotective role and prevents the development of excessive ethanol intake in rodents. However, studies showing the role of EE in chronic psychosocial stress-impaired ethanol-conditioned rewards are nonexistent. AIM The purpose of the current study is to explore the potential protective role of EE on extinction and reinstatement of ethanol-conditioned place preference (EtOH-CPP) following chronic psychosocial stress. METHODS In the first experiment and after the EtOH-CPP test, the mice were subjected to 15 days of chronic stress, then housed in a standard (SE) or enriched environment (EE) while EtOH-CPP extinction was achieved by repeated exposure to the CPP chambers without ethanol injection. In the second experiment and after the EtOH-CPP test, extinction was achieved as described above. Mice were then exposed to chronic stress for 2 weeks before being housed in a SE or EE. EtOH-CPP reinstatement was induced by a single exposure to the conditioning chambers. RESULTS As expected, stress exposure increased anxiety-like behavior and reduced weight gain. More importantly, we found that EE significantly shortened chronic stress-delayed extinction and decreased the reinstatement of EtOH-CPP. CONCLUSION These results support the hypothesis that EE reduces the impact of alcohol-associated environmental stimuli, and hence it may be a general intervention for reducing cue-elicited craving and relapse in humans.
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Affiliation(s)
- Amine Bahi
- College of Medicine, Ajman University, Ajman, UAE. .,Department of Anatomy, College of Medicine and Health Sciences, United Arab Emirates University, Al Ain, UAE.
| | - Jean-Luc Dreyer
- Division of Biochemistry, Department of Medicine, University of Fribourg, 1700, Fribourg, Switzerland
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Bahi A. Dopamine transporter gene expression within the nucleus accumbens plays important role in the acquisition and reinstatement of ethanol-seeking behavior in mice. Behav Brain Res 2020; 381:112475. [PMID: 31923430 DOI: 10.1016/j.bbr.2020.112475] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2019] [Revised: 12/15/2019] [Accepted: 01/06/2020] [Indexed: 11/26/2022]
Abstract
Alcoholism and alcohol use disorders are chronically relapsing conditions which is a major problem in treating alcohol addiction. In a previous study we showed that the dopamine transporter (DAT) is implicated in voluntary intake and preference. However, its role in modulating ethanol-associated contextual memory remains largely unknown. In this study we have investigated the role of DAT in ethanol-induced conditioned place preference (EtOH-CPP) acquisition and reinstatement in adult male C57BL/6 mice. For this purpose, we used both loss- and gain-of-function approaches to test the effects of central DAT manipulation on EtOH-CPP. We developed a lentiviral-mediated gene transfer approach to examine whether DAT knockdown (shDAT) or overexpression in the nucleus accumbens (Nacc) is enough to impair EtOH-CPP acquisition and reinstatement. In the first experiment, results showed that DAT knockdown blocked, whereas DAT overexpression, exacerbated the acquisition of EtOH-CPP. In the second experiment and after the EtOH-CPP expression, the mice were subjected to a 14-day extinction trials before drug-induced EtOH-CPP reinstatement was induced by a priming injection of 1 g/kg EtOH. Results indicated that reinstatement of EtOH-CPP was considerably decreased after accumbal shDAT injection. However, DAT overexpression significantly increased EtOH-CPP reinstatement. Finally, and following DAT mRNA quantification using RT-PCR, Pearson's correlation showed a strong positive relationship between accumbal DAT mRNA and EtOH-CPP acquisition and reinstatement. These results suggest that DAT expression in the Nacc is involved in the acquisition and retrieval of EtOH contextual memory and that blockade of this transporter can decrease the rewarding properties of EtOH.
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Affiliation(s)
- Amine Bahi
- College of Medicine, Ajman University, Ajman, UAE; Department of Anatomy, College of Medicine & Health Sciences, United Arab Emirates University, Al Ain, UAE.
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Vatankhah M, Sarihi A, Komaki A, Shahidi S, Haghparast A. AMN082—a metabotropic glutamate receptor type 7 allosteric agonist in the NAc facilitates extinction and inhibits the reinstatement of morphine-induced conditioned place preference in male rats. Brain Res Bull 2018; 140:28-33. [DOI: 10.1016/j.brainresbull.2018.03.017] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2017] [Revised: 03/23/2018] [Accepted: 03/26/2018] [Indexed: 11/27/2022]
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Lebourgeois S, Vilpoux C, Jeanblanc J, Acher F, Marie N, Noble F, Naassila M. Pharmacological activation of mGlu4 and mGlu7 receptors, by LSP2-9166, reduces ethanol consumption and relapse in rat. Neuropharmacology 2018; 133:163-170. [DOI: 10.1016/j.neuropharm.2018.01.031] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2017] [Revised: 01/12/2018] [Accepted: 01/24/2018] [Indexed: 12/13/2022]
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Hajasova Z, Canestrelli C, Acher F, Noble F, Marie N. Role of mGlu7 receptor in morphine rewarding effects is uncovered by a novel orthosteric agonist. Neuropharmacology 2018; 131:424-430. [PMID: 29307544 DOI: 10.1016/j.neuropharm.2018.01.002] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2017] [Revised: 12/26/2017] [Accepted: 01/02/2018] [Indexed: 11/26/2022]
Abstract
Opiate dependence is a major health issue and despite the existence of opioid substitution treatment, relapse frequently occurs. Group III metabotropic glutamate (mGlu) receptors has received much attention as a putative target in ethanol and cocaine addiction, but no data on opiate addiction exist. So we investigated the role of group III mGlu receptors in morphine rewarding effects through the expression and the reinstatement of conditioned place preference (CPP) using a newly synthesized mGlu4/mGlu7 receptor orthosteric agonist, LSP2-9166. We found that LSP2-9166 blocked morphine CPP expression and reinstatement after extinction. Blockade of CPP expression with LSP2-9166 was abolished when using XAP044, a mGlu7 antagonist. We also found that LSP2-9166 at the dose active for blocking morphine reward was devoid of any effect on locomotion, hedonic state, spatial memory, anxiety or depression. Altogether our data demonstrated that group III mGlu receptors, and more specifically mGlu7, might be a valuable target in opiate addiction.
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Affiliation(s)
- Zuzana Hajasova
- CNRS ERL 3649, Neuroplasticité et Thérapie des Addictions, Paris, France; INSERM UMR-S 1124, Paris, France; Université Paris Descartes, Paris, France
| | - Corinne Canestrelli
- CNRS ERL 3649, Neuroplasticité et Thérapie des Addictions, Paris, France; INSERM UMR-S 1124, Paris, France; Université Paris Descartes, Paris, France
| | - Francine Acher
- Université Paris Descartes, Paris, France; CNRS UMR8601, Laboratoire de Chimie & Biochimie Pharmacologiques et Toxicologiques, Paris, France
| | - Florence Noble
- CNRS ERL 3649, Neuroplasticité et Thérapie des Addictions, Paris, France; INSERM UMR-S 1124, Paris, France; Université Paris Descartes, Paris, France
| | - Nicolas Marie
- CNRS ERL 3649, Neuroplasticité et Thérapie des Addictions, Paris, France; INSERM UMR-S 1124, Paris, France; Université Paris Descartes, Paris, France.
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Bahi A. Environmental enrichment reduces chronic psychosocial stress-induced anxiety and ethanol-related behaviors in mice. Prog Neuropsychopharmacol Biol Psychiatry 2017; 77:65-74. [PMID: 28390969 DOI: 10.1016/j.pnpbp.2017.04.001] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/06/2017] [Revised: 03/07/2017] [Accepted: 04/02/2017] [Indexed: 12/21/2022]
Abstract
Previous research from our laboratory has shown that exposure to chronic psychosocial stress increased voluntary ethanol consumption and preference as well as acquisition of ethanol-induced conditioned place preference (CPP) in mice. This study was done to determine whether an enriched environment could have "curative" effects on chronic psychosocial stress-induced ethanol intake and CPP. For this purpose, experimental mice "intruders" were exposed to the chronic subordinate colony (CSC) housing for 19 consecutive days in the presence of an aggressive "resident" mouse. At the end of that period, mice were tested for their anxiety-like behavior using the elevated plus maze (EPM) test then housed in a standard or enriched environment (SE or EE respectively). Anxiety and ethanol-related behaviors were investigated using the open field (OF) test, a standard two-bottle choice drinking paradigm, and the CPP procedure. As expected, CSC exposure increased anxiety-like behavior and reduced weight gain as compared to single housed colony (SHC) controls. In addition, CSC exposure increased voluntary ethanol intake and ethanol-CPP. Interestingly, we found that EE significantly and consistently reduced anxiety and ethanol consumption and preference. However, neither tastants' (saccharin and quinine) intake nor blood ethanol metabolism were affected by EE. Finally, and most importantly, EE reduced the acquisition of CPP induced by 1.5g/kg ethanol. Taken together, these results support the hypothesis that EE can reduce voluntary ethanol intake and ethanol-induced conditioned reward and seems to be one of the strategies to reduce the behavioral deficits and the risk of anxiety-induced alcohol abuse.
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Affiliation(s)
- Amine Bahi
- Department of Anatomy, Tawam Medical Campus, United Arab Emirates University, Al Ain, United Arab Emirates.
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Bahi A. Decreased anxiety, voluntary ethanol intake and ethanol-induced CPP acquisition following activation of the metabotropic glutamate receptor 8 “mGluR8”. Pharmacol Biochem Behav 2017; 155:32-42. [DOI: 10.1016/j.pbb.2017.03.004] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/03/2017] [Revised: 03/14/2017] [Accepted: 03/16/2017] [Indexed: 10/19/2022]
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Goodwani S, Saternos H, Alasmari F, Sari Y. Metabotropic and ionotropic glutamate receptors as potential targets for the treatment of alcohol use disorder. Neurosci Biobehav Rev 2017; 77:14-31. [PMID: 28242339 DOI: 10.1016/j.neubiorev.2017.02.024] [Citation(s) in RCA: 55] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2016] [Revised: 02/13/2017] [Accepted: 02/22/2017] [Indexed: 12/16/2022]
Abstract
Emerging evidence indicates that dysfunctional glutamate neurotransmission is critical in the initiation and development of alcohol and drug dependence. Alcohol consumption induced downregulation of glutamate transporter 1 (GLT-1) as reported in previous studies from our laboratory. Glutamate is the major excitatory neurotransmitter in the brain, which acts via interactions with several glutamate receptors. Alcohol consumption interferes with the glutamatergic signal transmission by altering the functions of these receptors. Among the glutamate receptors involved in alcohol-drinking behavior are the metabotropic receptors such as mGluR1/5, mGluR2/3, and mGluR7, as well as the ionotropic receptors, NMDA and AMPA. Preclinical studies using agonists and antagonists implicate these glutamatergic receptors in the development of alcohol use disorder (AUD). Therefore, the purpose of this review is to discuss the neurocircuitry involving glutamate transmission in animals exposed to alcohol and further outline the role of metabotropic and ionotropic receptors in the regulation of alcohol-drinking behavior. This review provides ample information about the potential therapeutic role of glutamatergic receptors for the treatment of AUD.
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Affiliation(s)
- Sunil Goodwani
- University of Toledo, College of Pharmacy and Pharmaceutical Sciences, Department of Pharmacology and Experimental Therapeutics, Toledo, OH 43614, USA; The Neurodegeneration Consortium, Institute for Applied Cancer Science, The University of Texas MD Anderson Cancer Center, Houston, TX, 77054, USA
| | - Hannah Saternos
- University of Toledo, College of Pharmacy and Pharmaceutical Sciences, Department of Pharmacology and Experimental Therapeutics, Toledo, OH 43614, USA
| | - Fawaz Alasmari
- University of Toledo, College of Pharmacy and Pharmaceutical Sciences, Department of Pharmacology and Experimental Therapeutics, Toledo, OH 43614, USA
| | - Youssef Sari
- University of Toledo, College of Pharmacy and Pharmaceutical Sciences, Department of Pharmacology and Experimental Therapeutics, Toledo, OH 43614, USA.
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Melroy-Greif WE, Vadasz C, Kamens HM, McQueen MB, Corley RP, Stallings MC, Hopfer CJ, Krauter KS, Brown SA, Hewitt JK, Ehringer MA. Test for association of common variants in GRM7 with alcohol consumption. Alcohol 2016; 55:43-50. [PMID: 27788777 DOI: 10.1016/j.alcohol.2015.10.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2014] [Revised: 10/27/2015] [Accepted: 10/27/2015] [Indexed: 10/21/2022]
Abstract
Recent work using a mouse model has identified the glutamate metabotropic receptor 7 (Grm7) gene as a strong candidate gene for alcohol consumption. Although there has been some work examining the effect of human glutamate metabotropic receptor 7 (GRM7) polymorphisms on human substance use disorders, the majority of the work has focused on other psychiatric disorders such as ADHD, major depressive disorder, schizophrenia, bipolar disorder, panic disorder, and autism spectrum disorders. The current study aimed to evaluate evidence for association between GRM7 and alcohol behaviors in humans using a single nucleotide polymorphism (SNP) approach, as well as a gene-based approach. Using 1803 non-Hispanic European Americans (EAs) (source: the Colorado Center on Antisocial Drug Dependence [CADD]) and 1049 EA subjects from an independent replication sample (source: the Genetics of Antisocial Drug Dependence [GADD]), two SNPs in GRM7 were examined for possible association with alcohol consumption using two family-based association tests implemented in FBAT and QTDT. Rs3749380 was suggestively associated with alcohol consumption in the CADD sample (p = 0.010) with the minor T allele conferring risk. There was no evidence for association in the GADD sample. A gene-based test using four Genome-Wide Association Studies (GWAS) revealed no association between variation in GRM7 and alcohol consumption. This study had several limitations: the SNPs chosen likely do not tag expression quantitative trait loci; a human alcohol consumption phenotype was used, complicating the interpretation with respect to rodent studies that found evidence for a cis-regulatory link between alcohol preference and Grm7; and only common SNPs imputed in all four datasets were included in the gene-based test. These limitations highlight the fact that rare variants, some potentially important common signals in the gene, and regions farther upstream were not examined.
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Bahi A, Sadek B, Nurulain SM, Łażewska D, Kieć-Kononowicz K. The novel non-imidazole histamine H3 receptor antagonist DL77 reduces voluntary alcohol intake and ethanol-induced conditioned place preference in mice. Physiol Behav 2015; 151:189-97. [PMID: 26169446 DOI: 10.1016/j.physbeh.2015.07.012] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2015] [Revised: 06/28/2015] [Accepted: 07/08/2015] [Indexed: 12/16/2022]
Abstract
It has become clear that histamine H3 receptors (H3R) have been implicated in modulating ethanol intake and preference in laboratory animals. The novel non-imidazole H3R antagonist DL77 with excellent selectivity profile shows high in-vivo potency as well as in-vitro antagonist affinity with ED50 of 2.1 ± 0.2 mg/kg and pKi=8.08, respectively. In the present study, and applying an unlimited access two-bottle choice procedure, the anti-alcohol effects of the H3R antagonist, DL77 (0, 3, 10 and 30 mg/kg; i.p.), were investigated in adult mice. In this C57BL/6 line, effects of DL77 on voluntary alcohol intake and preference, as well as on total fluid intake were evaluated. Results have shown that DL77, dose-dependently, reduced both ethanol intake and preference. These effects were very selective as both saccharin and quinine, used to control for taste sensitivity, and intakes were not affected following DL77 pre-application. More importantly, systemic administration of DL77 (10 mg/kg) during acquisition inhibited ethanol-induced conditioned-place preference (EtOH-CPP) as measured using an unbiased protocol. The anti-alcohol activity observed for DL77 was abrogated when mice were pretreated with the selective H3R agonist R-(α)-methyl-histamine (RAMH) (10 mg/kg), or with the CNS penetrant H1R antagonist pyrilamine (PYR) (10mg/kg). These results suggest that DL77 has a predominant role in two in vivo effects of ethanol. Therefore, signaling via H3R is essential for ethanol-related consumption and conditioned reward and may represent a novel therapeutic pharmacological target to tackle ethanol abuse and alcoholism.
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Affiliation(s)
- Amine Bahi
- Department of Anatomy, College of Medicine & Health Sciences, United Arab Emirates University, Al Ain, United Arab Emirates.
| | - Bassem Sadek
- Department of Pharmacology & Therapeutics, College of Medicine & Health Sciences, United Arab Emirates University, Al Ain, United Arab Emirates
| | - Syed M Nurulain
- Department of Pharmacology & Therapeutics, College of Medicine & Health Sciences, United Arab Emirates University, Al Ain, United Arab Emirates
| | - Dorota Łażewska
- Jagiellonian University-Medical College, Faculty of Pharmacy, Department of Technology and Biotechnology of Drugs, Medyczna 9 St., 30-688 Kraków, Poland
| | - Katarzyna Kieć-Kononowicz
- Jagiellonian University-Medical College, Faculty of Pharmacy, Department of Technology and Biotechnology of Drugs, Medyczna 9 St., 30-688 Kraków, Poland
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Bahi A. The oxytocin receptor impairs ethanol reward in mice. Physiol Behav 2014; 139:321-7. [PMID: 25449413 DOI: 10.1016/j.physbeh.2014.11.046] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2014] [Revised: 11/13/2014] [Accepted: 11/14/2014] [Indexed: 01/24/2023]
Abstract
It is well established that oxytocin, and its receptor (OxtR), play a crucial role in addiction and that the stimulation of oxytocin neurotransmission reduces addictive behaviors to ethanol in laboratory animals. However, the impact of OxtR modulation on acquisition, extinction and reinstatement of drug-elicited ethanol-conditioned place preference (EtOH-CPP) has not yet been investigated. In this study, we evaluated the effects of OxtR pharmacological modulation, using the oxytocin analog Carbetocin, and genetic overexpression in the nucleus accumbens (NAcc), using lentiviral-mediated gene transfer technology, of the OxtR on acquisition, extinction and reinstatement of drug-elicited EtOH-CPP in mice. In the first experiment, results showed that Carbetocin administration and NAcc OxtR-overexpression (LV-OxtR) reduced EtOH-CPP establishment. In the second experiment, systemic Carbetocin treatment and OxtR overexpression resulted in decreased time spent in the ethanol-paired compartment following completion of a 7-day extinction protocol. Finally, the third experiment showed that Carbetocin and LV-OxtR suppressed primed reinstatement of EtOH-CPP. It is concluded that pharmacological and genetic modulation of the OxtR can modulate the acquisition, extinction, and reinstatement of conditioned reinforcing effects of ethanol. Taken together, the current findings add to the growing literature on oxytocin neurotransmission modulation in the pharmacotherapy of ethanol addiction and alcoholism.
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Affiliation(s)
- Amine Bahi
- Department of Anatomy, Tawam Medical Campus, College of Medicine & Health Sciences, United Arab Emirates University, Al Ain, United Arab Emirates.
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Bahi A, Nurulain SM, Ojha S. Ethanol intake and ethanol-conditioned place preference are reduced in mice treated with the bioflavonoid agent naringin. Alcohol 2014; 48:677-85. [PMID: 25288222 DOI: 10.1016/j.alcohol.2014.06.008] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2014] [Revised: 06/14/2014] [Accepted: 06/20/2014] [Indexed: 10/24/2022]
Abstract
Recently, PPAR-γ activation has emerged as a potential treatment for alcoholism. However, the adverse effects of synthetic PPAR-γ activators, despite being effective drugs, prompted the need for novel PPAR-γ agonists that retain efficacy and potency with a lower potential of side effects. Hence, naringin, a bioflavonoid isolated from citrus fruits and recently identified as a natural ligand of PPAR-γ, has begun to be evaluated for treatment of alcoholism. It is well known to possess several therapeutic benefits in addition to its anti-anxiety and antidepressant properties. In the present study, we assessed whether naringin treatment possesses anti-ethanol reward properties in C57BL/6 mice. We used the two-bottle choice drinking paradigm and ethanol-induced conditioned place preference (CPP) to examine the effect of naringin treatment on ethanol drinking. Results have shown that, compared with vehicle, naringin (10-100 mg/kg) significantly and dose-dependently decreased voluntary ethanol intake and preference in a two-bottle choice drinking paradigm [3-15% (v/v) escalating over 2 weeks], with no significant effect observed on saccharin [0.02-0.08% (w/v)] or on quinine [15-60 μM (w/v)] intake. In addition, there was no significant difference in blood ethanol concentration (BEC) between groups following naringin administration of 3 g of ethanol/kg body weight. Interestingly, when mice were treated with vehicle or naringin (30 mg/kg) before injection of ethanol (1.5 g/kg) during conditioning days, naringin inhibited the acquisition of ethanol-CPP. More importantly, these effects were significantly attenuated when mice were pre-injected with the peroxisome proliferator-activated receptor-γ (PPAR-γ) antagonist, GW9662. Taken together, the present findings are the first to implicate naringin and PPAR-γ receptors in the behavioral and reward-related effects of ethanol and raise the question of whether specific drugs that target PPAR-γ receptors could potentially reduce excessive ethanol consumption and preference.
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Al Maamari E, Al Ameri M, Al Mansouri S, Bahi A. Inhibition of urokinase plasminogen activator "uPA" activity alters ethanol consumption and conditioned place preference in mice. DRUG DESIGN DEVELOPMENT AND THERAPY 2014; 8:1391-403. [PMID: 25258509 PMCID: PMC4172050 DOI: 10.2147/dddt.s68636] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Urokinase plasminogen activator, uPA, is a serine protease implicated in addiction to drugs of abuse. Using its specific inhibitor, B428, we and others have characterized the role of uPA in the rewarding properties of psychostimulants, including cocaine and amphetamine, but none have examined the role of uPA in ethanol use disorders. Therefore, in the current study, we extended our observations to the role of uPA in ethanol consumption and ethanol-induced conditioned place preference. The general aim of the present series of experiments was to investigate the effects of the administration of the B428 on voluntary alcohol intake and ethanol conditioned reward. A two-bottle choice, unlimited-access paradigm was used to compare ethanol intake between vehicle- and 3, 10, and 30 mg/kg B428-administered mice. For this purpose, the mice were presented with an ethanol solution (2.5%-20%) and water, at each concentration for 4 days, and their consumption was measured daily. Consumption of saccharin and quinine solutions was also measured. Systemic administration of B428 dose-dependently decreased ethanol intake and preference. Additionally, B428 mice did not differ from vehicle mice in their intake of graded solutions of tastants, suggesting that the uPA inhibition did not alter taste function. Also, ethanol metabolism was not affected following B428 injection. More importantly, 1.5 g/kg ethanol-induced conditioned place preference acquisition was blocked following B428 administration. Taken together, our results are the first to implicate uPA inhibition in the regulation of ethanol consumption and preference, and suggest that uPA may be considered as a possible therapeutic drug target for alcoholism and abstinence.
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Affiliation(s)
- Elyazia Al Maamari
- Department of Anatomy, College of Medicine and Health Sciences, United Arab Emirates University, Al Ain, United Arab Emirates
| | - Mouza Al Ameri
- Department of Anatomy, College of Medicine and Health Sciences, United Arab Emirates University, Al Ain, United Arab Emirates
| | - Shamma Al Mansouri
- Department of Anatomy, College of Medicine and Health Sciences, United Arab Emirates University, Al Ain, United Arab Emirates
| | - Amine Bahi
- Department of Anatomy, College of Medicine and Health Sciences, United Arab Emirates University, Al Ain, United Arab Emirates
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Al Mansouri S, Ojha S, Al Maamari E, Al Ameri M, Nurulain SM, Bahi A. The cannabinoid receptor 2 agonist, β-caryophyllene, reduced voluntary alcohol intake and attenuated ethanol-induced place preference and sensitivity in mice. Pharmacol Biochem Behav 2014; 124:260-8. [DOI: 10.1016/j.pbb.2014.06.025] [Citation(s) in RCA: 69] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/18/2014] [Revised: 06/15/2014] [Accepted: 06/27/2014] [Indexed: 01/09/2023]
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Group III metabotropic glutamate receptors and drug addiction. Front Med 2014; 7:445-51. [PMID: 24078068 DOI: 10.1007/s11684-013-0291-1] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2013] [Accepted: 08/05/2013] [Indexed: 02/06/2023]
Abstract
Neuroadaptations of glutamatergic transmission in the limbic reward circuitry are linked to persistent drug addiction. Accumulating data have demonstrated roles of ionotropic glutamate receptors and group I and II metabotropic glutamate receptors (mGluRs) in this event. Emerging evidence also identifies Gαi/o-coupled group III mGluRs (mGluR4/7/8 subtypes enriched in the limbic system) as direct substrates of drugs of abuse and active regulators of drug action. Auto- and heteroreceptors of mGluR4/7/8 reside predominantly on nerve terminals of glutamatergic corticostriatal and GABAergic striatopallidal pathways, respectively. These presynaptic receptors regulate basal and/or phasic release of respective transmitters to maintain basal ganglia homeostasis. In response to operant administration of common addictive drugs, such as psychostimulants (cocaine and amphetamine), alcohol and opiates, limbic group III mGluRs undergo drastic adaptations to contribute to the enduring remodeling of excitatory synapses and to usually suppress drug seeking behavior. As a result, a loss-of-function mutation (knockout) of individual group III receptor subtypes often promotes drug seeking. This review summarizes the data from recent studies on three group III receptor subtypes (mGluR4/7/8) expressed in the basal ganglia and analyzes their roles in the regulation of dopamine and glutamate signaling in the striatum and their participation in the addictive properties of three major classes of drugs (psychostimulants, alcohol, and opiates).
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Vadasz C, Saito M. New glutamatergic target for alcohol and substance use disorder medications. Psychopharmacology (Berl) 2014; 231:1429-31. [PMID: 24619644 DOI: 10.1007/s00213-014-3496-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/16/2013] [Accepted: 01/29/2014] [Indexed: 11/30/2022]
Affiliation(s)
- Csaba Vadasz
- Nathan Kline Institute, Neurobehavioral Genetics, New York University School of Medicine, Psychiatry, New York, USA,
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Anton RF, Schacht JP, Book SW. Pharmacologic treatment of alcoholism. HANDBOOK OF CLINICAL NEUROLOGY 2014; 125:527-42. [PMID: 25307594 DOI: 10.1016/b978-0-444-62619-6.00030-6] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Progress in understanding the neuroscience of addiction has significantly advanced the development of more efficacious medications for the treatment of alcohol use disorders (AUD). While several medications have been approved by regulatory bodies around the world for the treatment of AUD, they are not universally efficacious. Recent research has yielded improved understanding of the genetics and brain circuits that underlie alcohol reward and its habitual use. This research has contributed to pharmacogenetic studies of medication response, and will ultimately lead to a more "personalized medicine" approach to AUD pharmacotherapy. This chapter summarizes work on clinically available medications (both approved by regulatory bodies and investigational) for the treatment of alcohol dependence, as well as the psychiatric disorders that are commonly comorbid with AUD. Studies that have evaluated genetic influences on medication response and those that have employed neuroimaging to probe mechanisms of medication action or response are highlighted. Finally, new targets discovered in animal models for possible pharmacologic intervention in humans are overviewed and future directions in medications development provided.
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Affiliation(s)
- Raymond F Anton
- Center for Drug and Alcohol Programs, Alcohol Research Center, Department of Psychiatry and Behavioral Sciences, Medical University of South Carolina, Charleston, SC, USA.
| | - Joseph P Schacht
- Center for Drug and Alcohol Programs, Alcohol Research Center, Department of Psychiatry and Behavioral Sciences, Medical University of South Carolina, Charleston, SC, USA
| | - Sarah W Book
- Center for Drug and Alcohol Programs, Alcohol Research Center, Department of Psychiatry and Behavioral Sciences, Medical University of South Carolina, Charleston, SC, USA
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Chronic psychosocial stress causes delayed extinction and exacerbates reinstatement of ethanol-induced conditioned place preference in mice. Psychopharmacology (Berl) 2014; 231:367-77. [PMID: 23978907 DOI: 10.1007/s00213-013-3243-1] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/01/2013] [Accepted: 08/06/2013] [Indexed: 10/26/2022]
Abstract
RATIONALE We have shown previously, using an animal model of voluntary ethanol intake and ethanol-conditioned place preference (EtOH-CPP), that exposure to chronic psychosocial stress induces increased ethanol intake and EtOH-CPP acquisition in mice. OBJECTIVE Here, we examined the impact of chronic subordinate colony (CSC) exposure on EtOH-CPP extinction, as well as ethanol-induced reinstatement of CPP. METHODS Mice were conditioned with saline or 1.5 g/kg ethanol and were tested in the EtOH-CPP model. In the first experiment, the mice were subjected to 19 days of chronic stress, and EtOH-CPP extinction was assessed during seven daily trials without ethanol injection. In the second experiment and after the EtOH-CPP test, the mice were subjected to 7 days of extinction trials before the 19 days of chronic stress. Drug-induced EtOH-CPP reinstatement was induced by a priming injection of 0.5 g/kg ethanol. RESULTS Compared to the single-housed colony mice, CSC mice exhibited increased anxiety-like behavior in the elevated plus maze (EPM) and the open field tests. Interestingly, the CSC mice showed delayed EtOH-CPP extinction. More importantly, CSC mice showed increased alcohol-induced reinstatement of the EtOH-CPP behavior. CONCLUSION Taken together, this study indicates that chronic psychosocial stress can have long-term effects on EtOH-CPP extinction as well as drug-induced reinstatement behavior and may provide a suitable model to study the latent effects of chronic psychosocial stress on extinction and relapse to drug abuse.
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Bahi A. Viral-mediated knockdown of mGluR7 in the nucleus accumbens mediates excessive alcohol drinking and increased ethanol-elicited conditioned place preference in rats. Neuropsychopharmacology 2013; 38:2109-19. [PMID: 22781839 PMCID: PMC3773660 DOI: 10.1038/npp.2012.122] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/30/2012] [Revised: 06/13/2012] [Accepted: 06/14/2012] [Indexed: 11/09/2022]
Abstract
Whether metabotropic glutamate 7 (mGluR7) -activation enhances or diminishes the reinforcing properties of psychostimulants remains unclear. We have previously shown that systemic mGluR7 activation reduced alcohol consumption and preference as well as locomotor-stimulating and rewarding properties of ethanol. In this study, we further examined the contribution of mGluR7 on the effect of ethanol within the nucleus accumbens (NAcc), a neural target for many drugs of abuse. Using short hairpin RNA (shRNA)-expressing lentiviral vectors (LV) to alter locally the activity of mGluR7 in male rats, we have shown that blocking mGluR7 expression increased ethanol consumption and preference in a two-bottle choice drinking paradigm with no effect either on saccharin or on quinine used for taste discrimination. In addition, mGluR7 knockdown increases preference for environments previously paired with low doses of ethanol in the conditioned place preference (CPP) test, as it shifted the dose-response curve for ethanol CPP to the left, indicating alterations in the rewarding effects of alcohol. More importantly, mGluR7 blockade in the dorsal striatum (DS) neither affected ethanol consumption nor ethanol-elicited CPP. These results show that levels of mGluR7 in the NAcc regulate responsiveness to alcohol. Taken together, these findings clearly demonstrate that mGluR7 signaling within the NAcc is a key modulator of functional responses to ethanol and offer an important target for regulating the addictive effects of alcohol.
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Affiliation(s)
- Amine Bahi
- Department of Anatomy, Faculty of Medicine and Health Sciences, United Arab Emirates University, Al Ain, UAE,Department of Anatomy, Faculty of Medicine & Health Sciences, Tawam Medical Campus, United Arab Emirates University, PO Box 17666, Al Ain, UAE, Tel: +971 3 7137 516, Fax: +971 3 7672 033, E-mail:
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Effects of group II and III metabotropic glutamate receptor ligands on conditioned taste aversion learning. Behav Brain Res 2013; 253:9-16. [DOI: 10.1016/j.bbr.2013.06.032] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2013] [Revised: 06/22/2013] [Accepted: 06/27/2013] [Indexed: 12/13/2022]
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Bahi A. Increased anxiety, voluntary alcohol consumption and ethanol-induced place preference in mice following chronic psychosocial stress. Stress 2013. [PMID: 23194312 DOI: 10.3109/10253890.2012.754419] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Stress exposure is known to be a risk factor for alcohol use and anxiety disorders. Comorbid chronic stress and alcohol dependence may lead to a complicated and potentially severe treatment profile. To gain an understanding of the interaction between chronic psychosocial stress and drug exposure, we studied the effects of concomitant chronic stress exposure on alcohol reward using two-bottle choice and ethanol-conditioned place preference (CPP). The study consisted of exposure of the chronic subordinate colony (CSC) mice "intruders" to an aggressive "resident" mouse for 19 consecutive days. Control mice were single housed (SHC). Ethanol consumption using two-bottle choice paradigm and ethanol CPP acquisition was assessed at the end of this time period. As expected, CSC exposure increased anxiety-like behavior and reduced weight gain as compared to SHC controls. Importantly, in the two-bottle choice procedure, CSC mice showed higher alcohol intake than SHC. When testing their response to ethanol-induced CPP, CSC mice achieved higher preference for the ethanol-paired chamber. In fact, CSC exposure increased ethanol-CPP acquisition. Taken together, these data demonstrate the long-term consequences of chronic psychosocial stress on alcohol intake in male mice, suggesting chronic stress as a risk factor for developing alcohol consumption and/or anxiety disorders.
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Affiliation(s)
- Amine Bahi
- Department of Anatomy, Tawam Medical Campus, CMHS, United Arab Emirates University, Al Ain, UAE.
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Influence of the novel histamine H₃ receptor antagonist ST1283 on voluntary alcohol consumption and ethanol-induced place preference in mice. Psychopharmacology (Berl) 2013; 228:85-95. [PMID: 23474889 DOI: 10.1007/s00213-013-3019-7] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/07/2012] [Accepted: 01/31/2013] [Indexed: 12/23/2022]
Abstract
RATIONALE Growing evidence supports a role for the central histaminergic system to have a modulatory influence on drug addiction in general and alcohol-use disorders in particular through histamine H3 receptors (H3R). OBJECTIVE In the present study, the effects of systemic injection of the newly synthesized H3R antagonist ST1283 on ethanol (EtOH) voluntary intake and EtOH-conditioned reward in mice have been investigated. METHODS Oral EtOH, saccharin, and quinine intake was assessed in a two-bottle choice paradigm using escalating concentrations of alcohol or tastant solutions. EtOH-induced place preference (CPP), EtOH-induced locomotor activity, and blood ethanol concentration (BEC) were also measured. RESULTS Following administration of the H3R antagonist (2.5, 5, and 10 mg/kg, i.p.), there was a significant dose-dependent decrease in alcohol consumption and preference. Importantly, vehicle- and ST1283 (5 mg/kg)-treated mice showed similar consumption and preference to increasing concentration of both sweet and bitter tastes. More interestingly, systemic administration of ST1283 inhibited EtOH-CPP and EtOH-enhanced locomotion. This inhibition was blocked when mice were pretreated with the selective H3R agonist R-(alpha)-methyl-histamine (10 mg/kg). Finally, vehicle- and ST1283-treated mice had similar BECs. CONCLUSION Our results show that ST1283 may decrease voluntary EtOH consumption and EtOH-CPP by altering its reinforcing effects, suggesting a novel role for histamine signaling in regulation of alcoholism. Lastly, the results add to the growing literature on H3R modulation in the pharmacotherapy of EtOH addiction.
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Bahi A, Tolle V, Fehrentz JA, Brunel L, Martinez J, Tomasetto CL, Karam SM. Ghrelin knockout mice show decreased voluntary alcohol consumption and reduced ethanol-induced conditioned place preference. Peptides 2013; 43:48-55. [PMID: 23428971 DOI: 10.1016/j.peptides.2013.02.008] [Citation(s) in RCA: 63] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/20/2013] [Revised: 02/11/2013] [Accepted: 02/11/2013] [Indexed: 02/07/2023]
Abstract
Recent work suggests that stomach-derived hormone ghrelin receptor (GHS-R1A) antagonism may reduce motivational aspects of ethanol intake. In the current study we hypothesized that the endogenous GHS-R1A agonist ghrelin modulates alcohol reward mechanisms. For this purpose ethanol-induced conditioned place preference (CPP), ethanol-induced locomotor stimulation and voluntary ethanol consumption in a two-bottle choice drinking paradigm were examined under conditions where ghrelin and its receptor were blocked, either using ghrelin knockout (KO) mice or the specific ghrelin receptor (GHS-R1A) antagonist "JMV2959". We showed that ghrelin KO mice displayed lower ethanol-induced CPP than their wild-type (WT) littermates. Consistently, when injected during CPP-acquisition, JMV2959 reduced CPP-expression in C57BL/6 mice. In addition, ethanol-induced locomotor stimulation was lower in ghrelin KO mice. Moreover, GHS-R1A blockade, using JMV2959, reduced alcohol-stimulated locomotion only in WT but not in ghrelin KO mice. When alcohol consumption and preference were assessed using the two-bottle choice test, both genetic deletion of ghrelin and pharmacological antagonism of the GHS-R1A (JMV2959) reduced voluntary alcohol consumption and preference. Finally, JMV2959-induced reduction of alcohol intake was only observed in WT but not in ghrelin KO mice. Taken together, these results suggest that ghrelin neurotransmission is necessary for the stimulatory effect of ethanol to occur, whereas lack of ghrelin leads to changes that reduce the voluntary intake as well as conditioned reward by ethanol. Our findings reveal a major, novel role for ghrelin in mediating ethanol behavior, and add to growing evidence that ghrelin is a key mediator of the effects of multiple abused drugs.
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Affiliation(s)
- Amine Bahi
- Department of Anatomy, College of Medicine and Health Sciences, United Arab Emirates University, Al Ain, United Arab Emirates.
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Bahi A, Dreyer JL. Striatal modulation of BDNF expression using microRNA124a-expressing lentiviral vectors impairs ethanol-induced conditioned-place preference and voluntary alcohol consumption. Eur J Neurosci 2013; 38:2328-37. [PMID: 23601049 DOI: 10.1111/ejn.12228] [Citation(s) in RCA: 74] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2012] [Revised: 03/21/2013] [Accepted: 03/22/2013] [Indexed: 12/25/2022]
Abstract
Alcohol abuse is a major health, economic and social concern in modern societies, but the exact molecular mechanisms underlying ethanol addiction remain elusive. Recent findings show that small non-coding microRNA (miRNA) signaling contributes to complex behavioral disorders including drug addiction. However, the role of miRNAs in ethanol-induced conditioned-place preference (CPP) and voluntary alcohol consumption has not yet been directly addressed. Here, we assessed the expression profile of miR124a in the dorsal striatum of rats upon ethanol intake. The results show that miR124a was downregulated in the dorso-lateral striatum (DLS) following alcohol drinking. Then, we identified brain-derived neurotrophic factor (BDNF) as a direct target of miR124a. In fact, BDNF mRNA was upregulated following ethanol drinking. We used lentiviral vector (LV) gene transfer technology to further address the role of miR124a and its direct target BDNF in ethanol-induced CPP and alcohol consumption. Results reveal that stereotaxic injection of LV-miR124a in the DLS enhances ethanol-induced CPP as well as voluntary alcohol consumption in a two-bottle choice drinking paradigm. Moreover, miR124a-silencer (LV-siR124a) as well as LV-BDNF infusion in the DLS attenuates ethanol-induced CPP as well as voluntary alcohol consumption. Importantly, LV-miR124a, LV-siR124a and LV-BDNF have no effect on saccharin and quinine intake. Our findings indicate that striatal miR124a and BDNF signaling have crucial roles in alcohol consumption and ethanol conditioned reward.
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Affiliation(s)
- Amine Bahi
- Department of Anatomy, Tawam Medical Campus, CMHS, United Arab Emirates University, Al Ain, UAE.
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Pharmacology of metabotropic glutamate receptor allosteric modulators: structural basis and therapeutic potential for CNS disorders. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2013; 115:61-121. [PMID: 23415092 DOI: 10.1016/b978-0-12-394587-7.00002-6] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
The metabotropic glutamate receptors (mGlus) mediate a neuromodulatory role throughout the brain for the major excitatory neurotransmitter, glutamate. Seven of the eight mGlu subtypes are expressed within the CNS and are attractive targets for a variety of psychiatric and neurological disorders including anxiety, depression, schizophrenia, Parkinson's disease, and Fragile X syndrome. Allosteric modulation of these class C 7-transmembrane spanning receptors represents a novel approach to facilitate development of mGlu subtype-selective probes and therapeutics. Allosteric modulators that interact with sites topographically distinct from the endogenous ligand-binding site offer a number of advantages over their competitive counterparts. In particular for CNS therapeutics, allosteric modulators have the potential to maintain the spatial and temporal aspects of endogenous neurotransmission. The past 15 years have seen the discovery of numerous subtype-selective allosteric modulators for the majority of the mGlu family members, including positive, negative, and neutral allosteric modulators, with a number of mGlu allosteric modulators now in clinical trials.
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