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Serra M, Faustini G, Brembati V, Casu MA, Pizzi M, Morelli M, Pinna A, Bellucci A. Early α-synuclein/synapsin III co-accumulation, nigrostriatal dopaminergic synaptopathy and denervation in the MPTPp mouse model of Parkinson's Disease. Exp Neurol 2024; 383:115040. [PMID: 39500391 DOI: 10.1016/j.expneurol.2024.115040] [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: 05/28/2024] [Revised: 10/25/2024] [Accepted: 10/28/2024] [Indexed: 11/10/2024]
Abstract
Parkinson's disease (PD) is characterized by the loss of nigrostriatal dopaminergic neurons and the presence of Lewy bodies (LB), intraneuronal inclusions mainly composed of α-synuclein (α-Syn) fibrils. Compelling evidence supports that, in PD brains, synapses are the sites where neurodegeneration initiates several years before the manifestation of motor symptoms. Furthermore, the amount of α-Syn deposited at synaptic terminals is several orders greater than that constituting LB. This hints that pathological synaptic α-Syn aggregates may be the main trigger for the retrograde synapse-to-cell body degeneration pattern characterizing early prodromal phases of PD. Identifying reliable biomarkers of synaptopathy is therefore crucial for early diagnosis. Here, we studied the alterations of key dopaminergic and non-dopaminergic striatal synaptic markers during the initial phases of axonal and cell body degeneration in mice subjected to 3 or 10 administrations of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine + probenecid (MPTPp), a model for early prodromal PD. We found that MPTPp administration resulted in progressive deposition of α-Syn, advancing from synaptic terminals to axons and dopaminergic neuron cell bodies. This was accompanied by marked co-accumulation of Synapsin III (Syn III), a synaptic protein previously identified as a component of α-Syn fibrils in post-mortem PD brains and as a main stabilizer of α-Syn aggregates, as well as very early and severe reduction of vesicular monoamine transporter 2 (VMAT2), dopamine transporter (DAT) and tyrosine hydroxylase (TH) immunoreactivity in nigrostriatal neurons. Results also showed that striatal α-Syn accumulation and VMAT2 decrease, unlike other markers, did not recover following washout from 10 MPTPp administrations, supporting that these changes were precocious and severe. Finally, we found that early changes in striatal α-Syn, Syn III, VMAT2 and DAT observed following 3 MPTPp administrations, correlated with nigrostriatal neuron loss after 10 MPTPp administrations. These findings indicate that α-Syn/Syn III co-deposition characterizes very early stages of striatal dopaminergic dysfunction in the MPTPp model and highlight that VMAT2 and Syn III could be two reliable molecular imaging biomarkers to predict dopamine neuron denervation and estimate α-Syn-related synaptopathy in prodromal and early symptomatic phases of PD.
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Affiliation(s)
- Marcello Serra
- Department of Biomedical Sciences, Section of Neuroscience, University of Cagliari, Cagliari, Italy
| | - Gaia Faustini
- Department of Molecular and Translational Medicine University of Brescia, Brescia, Italy
| | - Viviana Brembati
- Department of Molecular and Translational Medicine University of Brescia, Brescia, Italy
| | - Maria Antonietta Casu
- National Research Council of Italy, Institute of Translational Pharmacology, UOS of Cagliari, Scientific and Technological Park of Sardinia POLARIS, Pula, Italy
| | - Marina Pizzi
- Department of Molecular and Translational Medicine University of Brescia, Brescia, Italy
| | - Micaela Morelli
- Department of Biomedical Sciences, Section of Neuroscience, University of Cagliari, Cagliari, Italy; National Research Council of Italy, Neuroscience Institute, UOS of Cagliari, Italy
| | - Annalisa Pinna
- National Research Council of Italy, Neuroscience Institute, UOS of Cagliari, Italy.
| | - Arianna Bellucci
- Department of Molecular and Translational Medicine University of Brescia, Brescia, Italy.
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Tassan Mazzocco M, Serra M, Maspero M, Coliva A, Presotto L, Casu MA, Morelli M, Moresco RM, Belloli S, Pinna A. Positive relation between dopamine neuron degeneration and metabolic connectivity disruption in the MPTP plus probenecid mouse model of Parkinson's disease. Exp Neurol 2024; 374:114704. [PMID: 38281587 DOI: 10.1016/j.expneurol.2024.114704] [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: 10/11/2023] [Revised: 01/15/2024] [Accepted: 01/25/2024] [Indexed: 01/30/2024]
Abstract
The clinical manifestation of Parkinson's disease (PD) appears when neurodegeneration is already advanced, compromising the efficacy of disease-modifying treatment approaches. Biomarkers to identify the early stages of PD are therefore of paramount importance for the advancement of the therapy of PD. In the present study, by using a mouse model of PD obtained by subchronic treatment with the neurotoxin 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) and the clearance inhibitor probenecid (MPTPp), we identified prodromal markers of PD by combining in vivo positron emission tomography (PET) imaging and ex vivo immunohistochemistry. Longitudinal PET imaging of the dopamine transporter (DAT) by [18F]-N-(3-fluoropropyl)-2β-carboxymethoxy-3β-(4-iodophenyl) nortropane ([18F]-FP-CIT), and brain glucose metabolism by 2-deoxy-2-[18F]-fluoroglucose ([18F]-FDG) were performed before MPTPp treatment and after 1, 3, and 10 MPTPp administrations, in order to assess relation between dopamine neuron integrity and brain connectivity. The results show that in vivo [18F]-FP-CIT in the dorsal striatum was not modified after the first administration of MPTPp, tended to decrease after 3 administrations, and significantly decreased after 10 MPTPp administrations. Post-mortem immunohistochemical analyses of DAT and tyrosine hydroxylase (TH) in the striatum showed a positive correlation with [18F]-FP-CIT, confirming the validity of repeated MPTPp-treated mice as a model that can reproduce the progressive pathological changes in the early phases of PD. Analysis of [18F]-FDG uptake in several brain areas connected to the striatum showed that metabolic connectivity was progressively disrupted, starting from the first MPTPp administration, and that significant connections between cortical and subcortical regions were lost after 10 MPTPp administrations, suggesting an association between dopamine neuron degeneration and connectivity disruption in this PD model. The results of this study provide a relevant model, where new drugs that can alleviate neurodegeneration in PD could be evaluated preclinically.
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Affiliation(s)
- Margherita Tassan Mazzocco
- PhD Program in Neuroscience, Medicine and Surgery Department, University of Milano-Bicocca, Monza, Italy; Nuclear Medicine Department, San Raffaele Scientific Institute (IRCCS), Milan, Italy
| | - Marcello Serra
- Department of Biomedical Sciences, Section of Neuroscience, University of Cagliari, Cagliari, Italy
| | - Marco Maspero
- Nuclear Medicine Department, San Raffaele Scientific Institute (IRCCS), Milan, Italy; National Research Council of Italy, Institute of Molecular Bioimaging and Physiology, UOS of Segrate, Italy
| | - Angela Coliva
- Nuclear Medicine Department, San Raffaele Scientific Institute (IRCCS), Milan, Italy
| | - Luca Presotto
- Nuclear Medicine Department, San Raffaele Scientific Institute (IRCCS), Milan, Italy; Department of Physics "G. Occhialini", University of Milano - Bicocca, Milan, Italy
| | - Maria Antonietta Casu
- National Research Council of Italy, Institute of Translational Pharmacology, UOS of Cagliari, Scientific and Technological Park of Sardinia POLARIS, Pula, Italy
| | - Micaela Morelli
- Department of Biomedical Sciences, Section of Neuroscience, University of Cagliari, Cagliari, Italy; National Research Council of Italy, Neuroscience Institute, UOS of Cagliari, Italy
| | - Rosa Maria Moresco
- Nuclear Medicine Department, San Raffaele Scientific Institute (IRCCS), Milan, Italy; National Research Council of Italy, Institute of Molecular Bioimaging and Physiology, UOS of Segrate, Italy; School of Medicine and Surgery, University of Milano - Bicocca, Monza, Italy.
| | - Sara Belloli
- Nuclear Medicine Department, San Raffaele Scientific Institute (IRCCS), Milan, Italy; National Research Council of Italy, Institute of Molecular Bioimaging and Physiology, UOS of Segrate, Italy
| | - Annalisa Pinna
- National Research Council of Italy, Neuroscience Institute, UOS of Cagliari, Italy
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Scherma M, Palmas MF, Pisanu A, Masia P, Dedoni S, Camoglio C, Fratta W, Carta AR, Fadda P. Induction of Activity-Regulated Cytoskeleton-Associated Protein and c-Fos Expression in an Animal Model of Anorexia Nervosa. Nutrients 2023; 15:3830. [PMID: 37686862 PMCID: PMC10490422 DOI: 10.3390/nu15173830] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2023] [Revised: 08/19/2023] [Accepted: 08/28/2023] [Indexed: 09/10/2023] Open
Abstract
Anorexia nervosa (AN) is a complex eating disorder characterized by reduced caloric intake to achieve body-weight loss. Furthermore, over-exercise is commonly reported. In recent years, animal models of AN have provided evidence for neuroplasticity changes in specific brain areas of the mesocorticolimbic circuit, which controls a multitude of functions including reward, emotion, motivation, and cognition. The activity-regulated cytoskeleton-associated protein (Arc) is an immediate early gene that modulates several forms of synaptic plasticity and has been linked to neuropsychiatric illness. Since the role of Arc in AN has never been investigated, in this study we evaluated whether the anorexic-like phenotype reproduced by the activity-based anorexia (ABA) model may impact its expression in selected brain regions that belong to the mesocorticolimbic circuit (i.e., prefrontal cortex, nucleus accumbens, and hippocampus). The marker of neuronal activation c-Fos was also assessed. We found that the expression of both markers increased in all the analyzed brain areas of ABA rats in comparison to the control groups. Moreover, a negative correlation between the density of Arc-positive cells and body-weight loss was found. Together, our findings suggest the importance of Arc and neuroplasticity changes within the brain circuits involved in dysfunctional behaviors associated with AN.
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Affiliation(s)
- Maria Scherma
- Division of Neuroscience and Clinical Pharmacology, Department of Biomedical Sciences, University of Cagliari, 09042 Cagliari, Italy; (M.F.P.); (S.D.); (C.C.); (W.F.); (A.R.C.); (P.F.)
| | - Maria Francesca Palmas
- Division of Neuroscience and Clinical Pharmacology, Department of Biomedical Sciences, University of Cagliari, 09042 Cagliari, Italy; (M.F.P.); (S.D.); (C.C.); (W.F.); (A.R.C.); (P.F.)
| | - Augusta Pisanu
- Neuroscience Institute, Section of Cagliari, National Research Council (CNR), 09042 Cagliari, Italy;
| | - Paolo Masia
- Division of Neuroscience and Clinical Pharmacology, Department of Biomedical Sciences, University of Cagliari, 09042 Cagliari, Italy; (M.F.P.); (S.D.); (C.C.); (W.F.); (A.R.C.); (P.F.)
| | - Simona Dedoni
- Division of Neuroscience and Clinical Pharmacology, Department of Biomedical Sciences, University of Cagliari, 09042 Cagliari, Italy; (M.F.P.); (S.D.); (C.C.); (W.F.); (A.R.C.); (P.F.)
| | - Chiara Camoglio
- Division of Neuroscience and Clinical Pharmacology, Department of Biomedical Sciences, University of Cagliari, 09042 Cagliari, Italy; (M.F.P.); (S.D.); (C.C.); (W.F.); (A.R.C.); (P.F.)
| | - Walter Fratta
- Division of Neuroscience and Clinical Pharmacology, Department of Biomedical Sciences, University of Cagliari, 09042 Cagliari, Italy; (M.F.P.); (S.D.); (C.C.); (W.F.); (A.R.C.); (P.F.)
| | - Anna R. Carta
- Division of Neuroscience and Clinical Pharmacology, Department of Biomedical Sciences, University of Cagliari, 09042 Cagliari, Italy; (M.F.P.); (S.D.); (C.C.); (W.F.); (A.R.C.); (P.F.)
| | - Paola Fadda
- Division of Neuroscience and Clinical Pharmacology, Department of Biomedical Sciences, University of Cagliari, 09042 Cagliari, Italy; (M.F.P.); (S.D.); (C.C.); (W.F.); (A.R.C.); (P.F.)
- Neuroscience Institute, Section of Cagliari, National Research Council (CNR), 09042 Cagliari, Italy;
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Milella MS, D'Ottavio G, De Pirro S, Barra M, Caprioli D, Badiani A. Heroin and its metabolites: relevance to heroin use disorder. Transl Psychiatry 2023; 13:120. [PMID: 37031205 PMCID: PMC10082801 DOI: 10.1038/s41398-023-02406-5] [Citation(s) in RCA: 12] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/14/2022] [Revised: 03/17/2023] [Accepted: 03/21/2023] [Indexed: 04/10/2023] Open
Abstract
Heroin is an opioid agonist commonly abused for its rewarding effects. Since its synthesis at the end of the nineteenth century, its popularity as a recreational drug has ebbed and flowed. In the last three decades, heroin use has increased again, and yet the pharmacology of heroin is still poorly understood. After entering the body, heroin is rapidly deacetylated to 6-monoacetylmorphine (6-MAM), which is then deacetylated to morphine. Thus, drug addiction literature has long settled on the notion that heroin is little more than a pro-drug. In contrast to these former views, we will argue for a more complex interplay among heroin and its active metabolites: 6-MAM, morphine, and morphine-6-glucuronide (M6G). In particular, we propose that the complex temporal pattern of heroin effects results from the sequential, only partially overlapping, actions not only of 6-MAM, morphine, and M6G, but also of heroin per se, which, therefore, should not be seen as a mere brain-delivery system for its active metabolites. We will first review the literature concerning the pharmacokinetics and pharmacodynamics of heroin and its metabolites, then examine their neural and behavioral effects, and finally discuss the possible implications of these data for a better understanding of opioid reward and heroin addiction. By so doing we hope to highlight research topics to be investigated by future clinical and pre-clinical studies.
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Affiliation(s)
- Michele Stanislaw Milella
- Toxicology Unit, Policlinico Umberto I University Hospital, Rome, Italy.
- Laboratory affiliated to the Institute Pasteur Italia-Fondazione Cenci Bolognetti-Department of Physiology and Pharmacology, Sapienza University of Rome, Rome, Italy.
| | - Ginevra D'Ottavio
- Laboratory affiliated to the Institute Pasteur Italia-Fondazione Cenci Bolognetti-Department of Physiology and Pharmacology, Sapienza University of Rome, Rome, Italy
- Santa Lucia Foundation (IRCCS Fondazione Santa Lucia), Rome, Italy
| | - Silvana De Pirro
- Laboratory affiliated to the Institute Pasteur Italia-Fondazione Cenci Bolognetti-Department of Physiology and Pharmacology, Sapienza University of Rome, Rome, Italy
- Norwegian Centre for Addiction Research (SERAF), Faculty of Medicine, University of Oslo, Oslo, Norway
- Sussex Addiction and Intervention Centre (SARIC), School of Psychology, University of Sussex, Brighton, UK
| | | | - Daniele Caprioli
- Laboratory affiliated to the Institute Pasteur Italia-Fondazione Cenci Bolognetti-Department of Physiology and Pharmacology, Sapienza University of Rome, Rome, Italy.
- Santa Lucia Foundation (IRCCS Fondazione Santa Lucia), Rome, Italy.
| | - Aldo Badiani
- Laboratory affiliated to the Institute Pasteur Italia-Fondazione Cenci Bolognetti-Department of Physiology and Pharmacology, Sapienza University of Rome, Rome, Italy.
- Sussex Addiction and Intervention Centre (SARIC), School of Psychology, University of Sussex, Brighton, UK.
- Fondazione Villa Maraini, Rome, Italy.
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5
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Lubec J, Hussein AM, Kalaba P, Feyissa DD, Arias-Sandoval E, Cybulska-Klosowicz A, Bezu M, Stojanovic T, Korz V, Malikovic J, Aher NY, Zehl M, Dragacevic V, Leban JJ, Sagheddu C, Wackerlig J, Pistis M, Correa M, Langer T, Urban E, Höger H, Lubec G. Low-Affinity/High-Selectivity Dopamine Transport Inhibition Sufficient to Rescue Cognitive Functions in the Aging Rat. Biomolecules 2023; 13:biom13030467. [PMID: 36979402 PMCID: PMC10046369 DOI: 10.3390/biom13030467] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2023] [Revised: 02/21/2023] [Accepted: 02/27/2023] [Indexed: 03/06/2023] Open
Abstract
The worldwide increase in cognitive decline, both in aging and with psychiatric disorders, warrants a search for pharmacological treatment. Although dopaminergic treatment approaches represent a major step forward, current dopamine transporter (DAT) inhibitors are not sufficiently specific as they also target other transporters and receptors, thus showing unwanted side effects. Herein, we describe an enantiomerically pure, highly specific DAT inhibitor, S-CE-123, synthetized in our laboratory. Following binding studies to DAT, NET and SERT, GPCR and kinome screening, pharmacokinetics and a basic neurotoxic screen, S-CE-123 was tested for its potential to enhance and/or rescue cognitive functions in young and in aged rats in the non-invasive reward-motivated paradigm of a hole-board test for spatial learning. In addition, an open field study with young rats was carried out. We demonstrated that S-CE-123 is a low-affinity but highly selective dopamine reuptake inhibitor with good bioavailability. S-CE-123 did not induce hyperlocomotion or anxiogenic or stereotypic behaviour in young rats. Our compound improved the performance of aged but not young rats in a reward-motivated task. The well-described impairment of the dopaminergic system in aging may underlie the age-specific effect. We propose S-CE-123 as a possible candidate for developing a tentative therapeutic strategy for age-related cognitive decline and cognitive dysfunction in psychiatric disorders.
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Affiliation(s)
- Jana Lubec
- Programme for Proteomics, Paracelsus Medical University, 5020 Salzburg, Austria
| | - Ahmed M. Hussein
- Programme for Proteomics, Paracelsus Medical University, 5020 Salzburg, Austria
- Department of Pharmaceutical Sciences, Division of Pharmaceutical Chemistry, Faculty of Life Sciences, University of Vienna, 1090 Vienna, Austria
- Department of Zoology, Faculty of Science, Al-Azhar University, Assiut 71524, Egypt
| | - Predrag Kalaba
- Department of Pharmaceutical Sciences, Division of Pharmaceutical Chemistry, Faculty of Life Sciences, University of Vienna, 1090 Vienna, Austria
| | - Daniel Daba Feyissa
- Department of Pharmaceutical Sciences, Division of Pharmaceutical Chemistry, Faculty of Life Sciences, University of Vienna, 1090 Vienna, Austria
| | | | - Anita Cybulska-Klosowicz
- Neurobiology of Emotions Laboratory, Nencki Institute of Experimental Biology, 02093 Warsaw, Poland
| | - Mekite Bezu
- Department of Pharmaceutical Sciences, Division of Pharmaceutical Chemistry, Faculty of Life Sciences, University of Vienna, 1090 Vienna, Austria
| | - Tamara Stojanovic
- Programme for Proteomics, Paracelsus Medical University, 5020 Salzburg, Austria
| | - Volker Korz
- Programme for Proteomics, Paracelsus Medical University, 5020 Salzburg, Austria
| | - Jovana Malikovic
- Department of Pharmaceutical Sciences, Division of Pharmaceutical Chemistry, Faculty of Life Sciences, University of Vienna, 1090 Vienna, Austria
| | - Nilima Y. Aher
- Department of Pharmaceutical Sciences, Division of Pharmaceutical Chemistry, Faculty of Life Sciences, University of Vienna, 1090 Vienna, Austria
| | - Martin Zehl
- Department of Analytical Chemistry, Faculty of Chemistry, University of Vienna, 1090 Vienna, Austria
| | - Vladimir Dragacevic
- Programme for Proteomics, Paracelsus Medical University, 5020 Salzburg, Austria
- Department of Pharmaceutical Sciences, Division of Pharmaceutical Chemistry, Faculty of Life Sciences, University of Vienna, 1090 Vienna, Austria
| | - Johann Jakob Leban
- Programme for Proteomics, Paracelsus Medical University, 5020 Salzburg, Austria
| | - Claudia Sagheddu
- Department of Biomedical Sciences, Division of Neuroscience and Clinical Pharmacology, University of Cagliari, 09042 Monserrato, Italy
| | - Judith Wackerlig
- Department of Pharmaceutical Sciences, Division of Pharmaceutical Chemistry, Faculty of Life Sciences, University of Vienna, 1090 Vienna, Austria
| | - Marco Pistis
- Department of Biomedical Sciences, Division of Neuroscience and Clinical Pharmacology, University of Cagliari, 09042 Monserrato, Italy
- Section of Cagliari, Neuroscience Institute, National Research Council of Italy (CNR), 09042 Cagliari, Italy
| | - Merce Correa
- Department of Psychobiology, Universitat Jaume I, 12006 Castelló, Spain
- Department of Psychological Sciences, Behavioral Neuroscience Division, University of Connecticut, Storrs, CT 06269, USA
| | - Thierry Langer
- Department of Pharmaceutical Sciences, Division of Pharmaceutical Chemistry, Faculty of Life Sciences, University of Vienna, 1090 Vienna, Austria
| | - Ernst Urban
- Department of Pharmaceutical Sciences, Division of Pharmaceutical Chemistry, Faculty of Life Sciences, University of Vienna, 1090 Vienna, Austria
| | - Harald Höger
- Core Unit of Biomedical Research, Division of Laboratory Animal Science and Genetics, Medical University of Vienna, 2325 Himberg, Austria
| | - Gert Lubec
- Programme for Proteomics, Paracelsus Medical University, 5020 Salzburg, Austria
- Correspondence: ; Tel.: +43-676-569-4816
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Effects of the Phenethylamine 2-Cl-4,5-MDMA and the Synthetic Cathinone 3,4-MDPHP in Adolescent Rats: Focus on Sex Differences. Biomedicines 2022; 10:biomedicines10102336. [PMID: 36289598 PMCID: PMC9598216 DOI: 10.3390/biomedicines10102336] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2022] [Revised: 09/03/2022] [Accepted: 09/14/2022] [Indexed: 11/17/2022] Open
Abstract
The illicit drug market of novel psychoactive substances (NPSs) is expanding, becoming an alarming threat due to increasing intoxication cases and insufficient (if any) knowledge of their effects. Phenethylamine 2-chloro-4,5-methylenedioxymethamphetamine (2-Cl-4,5-MDMA) and synthetic cathinone 3,4-methylenedioxy-α-pyrrolidinohexanophenone (3,4-MDPHP) are new, emerging NPSs suggested to be particularly dangerous. This study verified whether these two new drugs (i) possess abuse liability, (ii) alter plasma corticosterone levels, and (iii) interfere with dopaminergic transmission; male and female adolescent rats were included to evaluate potential sex differences in the drug-induced effects. Findings show that the two NPSs are not able to sustain reliable self-administration behavior in rats, with cumulatively earned injections of drugs being not significantly different from cumulatively earned injections of saline in control groups. Yet, at the end of the self-administration training, females (but not males) exhibited higher plasma corticosterone levels after chronic exposure to low levels of 3,4-MDPHP (but not of 2-Cl-4,5-MDMA). Finally, electrophysiological patch-clamp recordings in the rostral ventral tegmental area (rVTA) showed that both drugs are able to increase the firing rate of rVTA dopaminergic neurons in males but not in females, confirming the sex dimorphic effects of these two NPSs. Altogether, this study demonstrates that 3,4-MDPHP and 2-Cl-4,5-MDMA are unlikely to induce dependence in occasional users but can induce other effects at both central and peripheral levels that may significantly differ between males and females.
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Li Y, Qu L, Li N, Wang X, Wang P, Ge SN, Wang XL. The optimized jugular vein catheterization reinforced cocaine self-administration addictive model for adult male Sprague-Dawley rats. Sci Rep 2022; 12:11711. [PMID: 35810209 PMCID: PMC9271077 DOI: 10.1038/s41598-022-15833-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2022] [Accepted: 06/30/2022] [Indexed: 11/19/2022] Open
Abstract
The self-administration (SA) model represents one of the most important and classic methods for drug addiction, and jugular vein catheterization is one of the most critical techniques in this animal model. We aimed to explore an optimized scheme to improve the success rate of rat jugular vein catheterization and SA model. Our experiment provided an optimized scheme which including numerous details, materials, approaches, updated techniques and protocols. Our experimental group consisted of 120 adult male Sprague–Dawley rats, which were divided into the Traditional Operation group (TO group) and the Optimized Operation group (OO group) by the random number table method and then further individually divided into the Saline Training group and the Cocaine Training group for the following SA training. Our results showed that the success rate of the jugular vein catheterization in the OO group was significantly greater than that in the TO group (93.33% vs 46.67%, χ2 = 31.11, P < 0.001). The optimized jugular vein catheterization could make the SA model more stable, reliable and efficient than the traditional operation. Compared with traditional methods, our optimized scheme made numerous improvements in materials and techniques including uniformity, individualized variability of the S-type positioning nail, the length and connection matching, the shape of the end and low cost. Our optimized scheme could provide a more stable and efficient tool for basic research on drug addiction. Several subtle improvements under our personal experience are usually important for augmenting operational efficiency.
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Affiliation(s)
- Yang Li
- Department of Neurosurgery, Tangdu Hospital, Air Force Medical University, Xi'an, Shaanxi, 710038, People's Republic of China.,Department of Neurosurgery, General Hospital of Central Theater Command, Wuhan, Hubei, 430070, China
| | - Liang Qu
- Department of Neurosurgery, Tangdu Hospital, Air Force Medical University, Xi'an, Shaanxi, 710038, People's Republic of China
| | - Nan Li
- Department of Neurosurgery, Tangdu Hospital, Air Force Medical University, Xi'an, Shaanxi, 710038, People's Republic of China
| | - Xin Wang
- Department of Neurosurgery, Tangdu Hospital, Air Force Medical University, Xi'an, Shaanxi, 710038, People's Republic of China
| | - Ping Wang
- Department of Neurosurgery, Tangdu Hospital, Air Force Medical University, Xi'an, Shaanxi, 710038, People's Republic of China
| | - Shun-Nan Ge
- Department of Neurosurgery, Tangdu Hospital, Air Force Medical University, Xi'an, Shaanxi, 710038, People's Republic of China.
| | - Xue-Lian Wang
- Department of Neurosurgery, Tangdu Hospital, Air Force Medical University, Xi'an, Shaanxi, 710038, People's Republic of China.
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8
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Galaj E, Xi ZX. Progress in opioid reward research: From a canonical two-neuron hypothesis to two neural circuits. Pharmacol Biochem Behav 2021; 200:173072. [PMID: 33227308 PMCID: PMC7796909 DOI: 10.1016/j.pbb.2020.173072] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/01/2020] [Revised: 10/21/2020] [Accepted: 11/10/2020] [Indexed: 12/12/2022]
Abstract
Opioid abuse and related overdose deaths continue to rise in the United States, contributing to the national opioid crisis in the USA. The neural mechanisms underlying opioid abuse and addiction are still not fully understood. This review discusses recent progress in basic research dissecting receptor mechanisms and circuitries underlying opioid reward and addiction. We first review the canonical GABA-dopamine neuron hypothesis that was upheld for half a century, followed by major findings challenging this hypothesis. We then focus on recent progress in research evaluating the role of the mesolimbic and nigrostriatal dopamine circuitries in opioid reward and relapse. Based on recent findings that activation of dopamine neurons in the ventral tegmental area (VTA) and substantia nigra pars compacta (SNc) is equally rewarding and that GABA neurons in the rostromedial tegmental nucleus (RMTg) and the substantia nigra pars reticula (SNr) are rich in mu opioid receptors and directly synapse onto midbrain DA neurons, we proposed that the RTMg→VTA → ventrostriatal and SNr → SNc → dorsostriatal pathways may act as the two major neural substrates underlying opioid reward and abuse. Lastly, we discuss possible integrations of these two pathways during initial opioid use, development of opioid abuse and maintenance of compulsive opioid seeking.
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Affiliation(s)
- Ewa Galaj
- Addiction Biology Unit, Molecular Targets and Medications Discovery Branch, National Institute on Drug Abuse, Intramural Research Program, Baltimore, MD, United States of America
| | - Zheng-Xiong Xi
- Addiction Biology Unit, Molecular Targets and Medications Discovery Branch, National Institute on Drug Abuse, Intramural Research Program, Baltimore, MD, United States of America.
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9
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Wright WJ, Dong Y. Psychostimulant-Induced Adaptations in Nucleus Accumbens Glutamatergic Transmission. Cold Spring Harb Perspect Med 2020; 10:cshperspect.a039255. [PMID: 31964644 DOI: 10.1101/cshperspect.a039255] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Carrying different aspects of emotional and motivational signals, glutamatergic synaptic projections from multiple limbic and paralimbic brain regions converge to the nucleus accumbens (NAc), in which these arousing signals are processed and prioritized for behavioral output. In animal models of drug addiction, some key drug-induced alterations at NAc glutamatergic synapses underlie important cellular and circuit mechanisms that promote subsequent drug taking, seeking, and relapse. With the focus of cocaine, we review changes at NAc glutamatergic synapses that occur after different drug procedures and abstinence durations, and the behavioral impact of these changes.
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Affiliation(s)
- William J Wright
- Department of Neuroscience, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, USA
| | - Yan Dong
- Department of Neuroscience, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, USA
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Khosrowabadi E, Karimi-Haghighi S, Jamali S, Haghparast A. Differential Roles of Intra-accumbal Orexin Receptors in Acquisition and Expression of Methamphetamine-Induced Conditioned Place Preference in the Rats. Neurochem Res 2020; 45:2230-2241. [DOI: 10.1007/s11064-020-03084-1] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2020] [Revised: 06/21/2020] [Accepted: 07/02/2020] [Indexed: 12/26/2022]
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11
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Galaj E, Newman AH, Xi ZX. Dopamine D3 receptor-based medication development for the treatment of opioid use disorder: Rationale, progress, and challenges. Neurosci Biobehav Rev 2020; 114:38-52. [PMID: 32376243 PMCID: PMC7252042 DOI: 10.1016/j.neubiorev.2020.04.024] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2020] [Accepted: 04/28/2020] [Indexed: 01/11/2023]
Abstract
Opioid abuse and related overdose deaths continue to rise in the United States, contributing to the current national opioid crisis. Although several opioid-based pharmacotherapies are available (e.g., methadone, buprenorphine, naloxone), they show limited effectiveness in long-term relapse prevention. In response to the opioid crisis, the National Institute on Drug Abuse proposed a list of pharmacological targets of highest priority for medication development for the treatment of opioid use disorders (OUD). Among these are antagonists of dopamine D3 receptors (D3R). In this review, we first review recent progress in research of the dopamine hypothesis of opioid reward and abuse and then describe the rationale and recent development of D3R ligands for the treatment of OUD. Herein, an emphasis is placed on the effectiveness of newly developed D3R antagonists in the animal models of OUD. These new drug candidates may also potentiate the analgesic effects of clinically used opioids, making them attractive as adjunctive medications for pain management and treatment of OUD.
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Affiliation(s)
- Ewa Galaj
- Molecular Targets and Medication Discovery Branch, National Institute on Drug Abuse, Intramural Research Program, Baltimore, MD, United States
| | - Amy Hauck Newman
- Molecular Targets and Medication Discovery Branch, National Institute on Drug Abuse, Intramural Research Program, Baltimore, MD, United States
| | - Zheng-Xiong Xi
- Molecular Targets and Medication Discovery Branch, National Institute on Drug Abuse, Intramural Research Program, Baltimore, MD, United States.
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Vassilev P, Avvisati R, Koya E, Badiani A. Distinct Populations of Neurons Activated by Heroin and Cocaine in the Striatum as Assessed by catFISH. eNeuro 2020; 7:ENEURO.0394-19.2019. [PMID: 31937522 PMCID: PMC7005257 DOI: 10.1523/eneuro.0394-19.2019] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2019] [Revised: 11/30/2019] [Accepted: 12/19/2019] [Indexed: 12/13/2022] Open
Abstract
Despite the still prevailing notion of a shared substrate of action for all addictive drugs, there is evidence suggesting that opioid and psychostimulant drugs differ substantially in terms of their neurobiological and behavioral effects. These differences may reflect separate neural circuits engaged by the two drugs. Here we used the catFISH (cellular compartment analysis of temporal activity by fluorescence in situ hybridization) technique to investigate the degree of overlap between neurons engaged by heroin versus cocaine in adult male Sprague Dawley rats. The catFISH technique is a within-subject procedure that takes advantage of the different transcriptional time course of the immediate-early genes homer 1a and arc to determine to what extent two stimuli separated by an interval of 25 min engage the same neuronal population. We found that throughout the striatal complex the neuronal populations activated by noncontingent intravenous injections of cocaine (800 μg/kg) and heroin (100 and 200 μg/kg), administered at an interval of 25 min from each other, overlapped to a much lesser extent than in the case of two injections of cocaine (800 μg/kg), also 25 min apart. The greatest reduction in overlap between populations activated by cocaine and heroin was in the dorsomedial and dorsolateral striatum (∼30% and ∼22%, respectively, of the overlap observed for the sequence cocaine-cocaine). Our results point toward a significant separation between neuronal populations activated by heroin and cocaine in the striatal complex. We propose that our findings are a proof of concept that these two drugs are encoded differently in a brain area believed to be a common neurobiological substrate to drug abuse.
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Affiliation(s)
- Philip Vassilev
- Sussex Addiction Research and Intervention Centre (SARIC), School of Psychology, University of Sussex, Brighton BN1 9RH, United Kingdom
| | - Riccardo Avvisati
- Sussex Addiction Research and Intervention Centre (SARIC), School of Psychology, University of Sussex, Brighton BN1 9RH, United Kingdom
| | - Eisuke Koya
- Sussex Addiction Research and Intervention Centre (SARIC), School of Psychology, University of Sussex, Brighton BN1 9RH, United Kingdom
| | - Aldo Badiani
- Sussex Addiction Research and Intervention Centre (SARIC), School of Psychology, University of Sussex, Brighton BN1 9RH, United Kingdom
- Department of Physiology and Pharmacology, Sapienza University of Rome, 00185 Rome, Italy
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Badiani A, Caprioli D, De Pirro S. Opposite environmental gating of the experienced utility ('liking') and decision utility ('wanting') of heroin versus cocaine in animals and humans: implications for computational neuroscience. Psychopharmacology (Berl) 2019; 236:2451-2471. [PMID: 31289884 PMCID: PMC6695361 DOI: 10.1007/s00213-019-05318-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/19/2019] [Accepted: 06/30/2019] [Indexed: 12/21/2022]
Abstract
BACKGROUND In this paper, we reviewed translational studies concerned with environmental influences on the rewarding effects of heroin versus cocaine in rats and humans with substance use disorder. These studies show that both experienced utility ('liking') and decision utility ('wanting') of heroin and cocaine shift in opposite directions as a function of the setting in which these drugs were used. Briefly, rats and humans prefer using heroin at home but cocaine outside the home. These findings appear to challenge prevailing theories of drug reward, which focus on the notion of shared substrate of action for drug of abuse, and in particular on their shared ability to facilitate dopaminergic transmission. AIMS Thus, in the second part of the paper, we verified whether our findings could be accounted for by available computational models of reward. To account for our findings, a model must include a component that could mediate the substance-specific influence of setting on drug reward RESULTS: It appears of the extant models that none is fully compatible with the results of our studies. CONCLUSIONS We hope that this paper will serve as stimulus to design computational models more attuned to the complex mechanisms responsible for the rewarding effects of drugs in real-world contexts.
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Affiliation(s)
- Aldo Badiani
- Department of Physiology and Pharmacology, Sapienza University of Rome, Rome, Italy.
- Sussex Addiction Research & Intervention Centre (SARIC) and School of Psychology, University of Sussex, Brighton, UK.
| | - Daniele Caprioli
- Department of Physiology and Pharmacology, Sapienza University of Rome, Rome, Italy
- Santa Lucia Foundation (IRCCS Fondazione Santa Lucia), Rome, Italy
| | - Silvana De Pirro
- Department of Physiology and Pharmacology, Sapienza University of Rome, Rome, Italy
- Sussex Addiction Research & Intervention Centre (SARIC) and School of Psychology, University of Sussex, Brighton, UK
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Glucagon-Like Peptide-1 Receptor Agonist Treatment Does Not Reduce Abuse-Related Effects of Opioid Drugs. eNeuro 2019; 6:eN-NRS-0443-18. [PMID: 31058214 PMCID: PMC6498420 DOI: 10.1523/eneuro.0443-18.2019] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2018] [Revised: 02/19/2019] [Accepted: 02/28/2019] [Indexed: 12/29/2022] Open
Abstract
Dependence on opioids and the number of opioid overdose deaths are serious and escalating public health problems, but medication-assisted treatments for opioid addiction remain inadequate for many patients. Glucagon-like pepide-1 (GLP-1) is a gut hormone and neuropeptide with actions in peripheral tissues and in the brain, including regulation of blood glucose and food intake. GLP-1 analogs, which are approved diabetes medications, can reduce the reinforcing and rewarding effects of alcohol, cocaine, amphetamine, and nicotine in rodents. Investigations on effects of GLP-1 analogs on opioid reward and reinforcement have not been reported. We assessed the effects of the GLP-1 receptor agonist Exendin-4 (Ex4) on opioid-related behaviors in male mice, i.e., morphine-conditioned place preference (CPP), intravenous self-administration (IVSA) of the short-acting synthetic opioid remifentanil, naltrexone-precipitated morphine withdrawal, morphine analgesia (male and female mice), and locomotor activity. Ex4 treatment had no effect on morphine-induced CPP, withdrawal, or hyperlocomotion. Ex4 failed to decrease remifentanil self-administration, if anything reinforcing effects of remifentanil appeared increased in Ex4-treated mice relative to saline. Ex4 did not significantly affect analgesia. In contrast, Ex4 dose dependently decreased oral alcohol self-administration, and suppressed spontaneous locomotor activity. Taken together, Ex4 did not attenuate the addiction-related behavioral effects of opioids, indicating that GLP-1 analogs would not be useful medications in the treatment of opioid addiction. This difference between opioids and other drug classes investigated to date may shed light on the mechanism of action of GLP-1 receptor treatment in the addictive effects of alcohol, central stimulants, and nicotine.
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De Luca MT, Montanari C, Meringolo M, Contu L, Celentano M, Badiani A. Heroin versus cocaine: opposite choice as a function of context but not of drug history in the rat. Psychopharmacology (Berl) 2019; 236:787-798. [PMID: 30443795 PMCID: PMC6469678 DOI: 10.1007/s00213-018-5115-1] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/05/2018] [Accepted: 11/06/2018] [Indexed: 12/26/2022]
Abstract
RATIONALE Previous studies have shown that rats trained to self-administer heroin and cocaine exhibit opposite preferences, as a function of setting, when tested in a choice paradigm. Rats tested at home prefer heroin to cocaine, whereas rats tested outside the home prefer cocaine to heroin. Here, we investigated whether drug history would influence subsequent drug preference in distinct settings. Based on a theoretical model of drug-setting interaction, we predicted that regardless of drug history rats would prefer heroin at home and cocaine outside the home. METHODS Rats with double-lumen catheters were first trained to self-administer either heroin (25 μg/kg) or cocaine (400 μg/kg) for 12 consecutive sessions. Twenty-six rats were housed in the self-administration chambers (thus, they were tested at home), whereas 30 rats lived in distinct home cages and were transferred to self-administration chambers only for the self-administration session (thus, they were tested outside the home). The rats were then allowed to choose repeatedly between heroin and cocaine within the same session for seven sessions. RESULTS Regardless of the training drug, the rats tested outside the home preferred cocaine to heroin, whereas the rats tested at home preferred heroin to cocaine. There was no correlation between drug preference and drug intake during the training phase. CONCLUSION Drug preferences were powerfully influenced by the setting but, quite surprisingly, not by drug history. This suggests that, under certain conditions, associative learning processes and drug-induced neuroplastic adaptations play a minor role in shaping individual preferences for one drug or the other.
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Affiliation(s)
- Maria Teresa De Luca
- Department of Physiology and Pharmacology Vittorio Erspamer, Sapienza University of Rome, Rome, Italy
| | - Christian Montanari
- Department of Physiology and Pharmacology Vittorio Erspamer, Sapienza University of Rome, Rome, Italy
| | - Maria Meringolo
- Department of Physiology and Pharmacology Vittorio Erspamer, Sapienza University of Rome, Rome, Italy
| | - Laura Contu
- Department of Physiology and Pharmacology Vittorio Erspamer, Sapienza University of Rome, Rome, Italy
| | - Michele Celentano
- Department of Physiology and Pharmacology Vittorio Erspamer, Sapienza University of Rome, Rome, Italy
| | - Aldo Badiani
- Department of Physiology and Pharmacology Vittorio Erspamer, Sapienza University of Rome, Rome, Italy.
- Sussex Addiction Research and Intervention Centre (SARIC), School of Psychology, University of Sussex, Sussex, UK.
- Sussex Neuroscience, University of Sussex, Sussex, UK.
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Corre J, van Zessen R, Loureiro M, Patriarchi T, Tian L, Pascoli V, Lüscher C. Dopamine neurons projecting to medial shell of the nucleus accumbens drive heroin reinforcement. eLife 2018; 7:39945. [PMID: 30373717 PMCID: PMC6207421 DOI: 10.7554/elife.39945] [Citation(s) in RCA: 112] [Impact Index Per Article: 18.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2018] [Accepted: 10/17/2018] [Indexed: 12/21/2022] Open
Abstract
The dopamine (DA) hypothesis posits the increase of mesolimbic dopamine levels as a defining commonality of addictive drugs, initially causing reinforcement, eventually leading to compulsive consumption. While much experimental evidence from psychostimulants supports this hypothesis, it has been challenged for opioid reinforcement. Here, we monitor genetically encoded DA and calcium indicators as well as cFos in mice to reveal that heroin activates DA neurons located in the medial part of the VTA, preferentially projecting to the medial shell of the nucleus accumbens (NAc). Chemogenetic and optogenetic manipulations of VTA DA or GABA neurons establish a causal link to heroin reinforcement. Inhibition of DA neurons blocked heroin self-administration, while heroin inhibited optogenetic self-stimulation of DA neurons. Likewise, heroin occluded the self-inhibition of VTA GABA neurons. Together, these experiments support a model of disinhibition of a subset of VTA DA neurons in opioid reinforcement.
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Affiliation(s)
- Julie Corre
- Department of Basic Neurosciences, Medical Faculty, University of Geneva, Geneva, Switzerland
| | - Ruud van Zessen
- Department of Basic Neurosciences, Medical Faculty, University of Geneva, Geneva, Switzerland
| | - Michaël Loureiro
- Department of Basic Neurosciences, Medical Faculty, University of Geneva, Geneva, Switzerland
| | - Tommaso Patriarchi
- School of Medicine, Department of Biochemistry and Molecular Medicine, University of California Davis, California, United States
| | - Lin Tian
- School of Medicine, Department of Biochemistry and Molecular Medicine, University of California Davis, California, United States
| | - Vincent Pascoli
- Department of Basic Neurosciences, Medical Faculty, University of Geneva, Geneva, Switzerland
| | - Christian Lüscher
- Department of Basic Neurosciences, Medical Faculty, University of Geneva, Geneva, Switzerland.,Service of Neurology, University of Geneva Hospital, Geneva, Switzerland
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Serotonin 2B Receptors in Mesoaccumbens Dopamine Pathway Regulate Cocaine Responses. J Neurosci 2017; 37:10372-10388. [PMID: 28935766 DOI: 10.1523/jneurosci.1354-17.2017] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2017] [Revised: 09/12/2017] [Accepted: 09/13/2017] [Indexed: 12/21/2022] Open
Abstract
Addiction is a maladaptive pattern of behavior following repeated use of reinforcing drugs in predisposed individuals, leading to lifelong changes. Common among these changes are alterations of neurons releasing dopamine in the ventral and dorsal territories of the striatum. The serotonin 5-HT2B receptor has been involved in various behaviors, including impulsivity, response to antidepressants, and response to psychostimulants, pointing toward putative interactions with the dopamine system. Despite these findings, it remains unknown whether 5-HT2B receptors directly modulate dopaminergic activity and the possible mechanisms involved. To answer these questions, we investigated the contribution of 5-HT2B receptors to cocaine-dependent behavioral responses. Male mice permanently lacking 5-HT2B receptors, even restricted to dopamine neurons, developed heightened cocaine-induced locomotor responses. Retrograde tracing combined with single-cell mRNA amplification indicated that 5-HT2B receptors are expressed by mesolimbic dopamine neurons. In vivo and ex vivo electrophysiological recordings showed that 5-HT2B-receptor inactivation in dopamine neurons affects their neuronal activity and increases AMPA-mediated over NMDA-mediated excitatory synaptic currents. These changes are associated with lower ventral striatum dopamine activity and blunted cocaine self-administration. These data identify the 5-HT2B receptor as a pharmacological intermediate and provide mechanistic insight into attenuated dopamine tone following exposure to drugs of abuse.SIGNIFICANCE STATEMENT Here we report that mice lacking 5-HT2B receptors totally or exclusively in dopamine neurons exhibit heightened cocaine-induced locomotor responses. Despite the sensitized state of these mice, we found that associated changes include lower ventral striatum dopamine activity and lower cocaine operant self-administration. We described the selective expression of 5-HT2B receptors in a subpopulation of dopamine neurons sending axons to the ventral striatum. Increased bursting in vivo properties of these dopamine neurons and a concomitant increase in AMPA synaptic transmission to ex vivo dopamine neurons were found in mice lacking 5-HT2B receptors. These data support the idea that the chronic 5-HT2B-receptor inhibition makes mice behave like animals already exposed to cocaine with higher cocaine-induced locomotion associated with changes in dopamine neuron reactivity.
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Barson JR, Leibowitz SF. Orexin/Hypocretin System: Role in Food and Drug Overconsumption. INTERNATIONAL REVIEW OF NEUROBIOLOGY 2017; 136:199-237. [PMID: 29056152 DOI: 10.1016/bs.irn.2017.06.006] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The neuropeptide orexin/hypocretin (OX), while largely transcribed within the hypothalamus, is released throughout the brain to affect complex behaviors. Primarily through the hypothalamus itself, OX homeostatically regulates adaptive behaviors needed for survival, including food intake, sleep-wake regulation, mating, and maternal behavior. However, through extrahypothalamic limbic brain regions, OX promotes seeking and intake of rewarding substances of abuse, like palatable food, alcohol, nicotine, and cocaine. This neuropeptide, in turn, is stimulated by the intake of or early life exposure to these substances, forming a nonhomeostatic, positive feedback loop. The specific OX receptor involved in these behaviors, whether adaptive behavior or substance seeking and intake, is dependent on the particular brain region that contributes to them. Thus, we propose that, while the primary function of OX is to maintain arousal for the performance of adaptive behaviors, this neuropeptide system is readily co-opted by rewarding substances that involve positive feedback, ultimately promoting their abuse.
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Affiliation(s)
- Jessica R Barson
- Drexel University College of Medicine, Philadelphia, PA, United States
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Abstract
This paper is the thirty-eighth consecutive installment of the annual review of research concerning the endogenous opioid system. It summarizes papers published during 2015 that studied the behavioral effects of molecular, pharmacological and genetic manipulation of opioid peptides, opioid receptors, opioid agonists and opioid antagonists. The particular topics that continue to be covered include the molecular-biochemical effects and neurochemical localization studies of endogenous opioids and their receptors related to behavior, and the roles of these opioid peptides and receptors in pain and analgesia, stress and social status, tolerance and dependence, learning and memory, eating and drinking, drug abuse and alcohol, sexual activity and hormones, pregnancy, development and endocrinology, mental illness and mood, seizures and neurologic disorders, electrical-related activity and neurophysiology, general activity and locomotion, gastrointestinal, renal and hepatic functions, cardiovascular responses, respiration and thermoregulation, and immunological responses.
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Affiliation(s)
- Richard J Bodnar
- Department of Psychology and Neuropsychology Doctoral Sub-Program, Queens College, City University of New York, Flushing, NY 11367, United States.
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Abstract
Classic hallucinogens share pharmacology as serotonin 5-HT2A, 5-HT2B, and 5-HT2C receptor agonists. Unique among most other Schedule 1 drugs, they are generally non-addictive and can be effective tools in the treatment of addiction. Mechanisms underlying these attributes are largely unknown. However, many preclinical studies show that 5-HT2C agonists counteract the addictive effects of drugs from several classes, suggesting this pharmacological property of classic hallucinogens may be significant. Drawing from a comprehensive analysis of preclinical behavior, neuroanatomy, and neurochemistry studies, this review builds rationale for this hypothesis, and also proposes a testable, neurobiological framework. 5-HT2C agonists work, in part, by modulating dopamine neuron activity in the ventral tegmental area-nucleus accumbens (NAc) reward pathway. We argue that activation of 5-HT2C receptors on NAc shell, GABAergic, medium spiny neurons inhibits potassium Kv1.x channels, thereby enhancing inhibitory activity via intrinsic mechanisms. Together with experiments that show that addictive drugs, such as cocaine, potentiate Kv1.x channels, thereby suppressing NAc shell GABAergic activity, this hypothesis provides a mechanism by which classic hallucinogen-mediated stimulation of 5-HT2C receptors could thwart addiction. It also provides a potential reason for the non-addictive nature of classic hallucinogens.
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Affiliation(s)
- Clinton E Canal
- Center for Drug Discovery, Department of Pharmaceutical Sciences, Northeastern University, Boston, USA
| | - Kevin S Murnane
- Department of Pharmaceutical Sciences, Mercer University College of Pharmacy, Mercer University Health Sciences Center, Atlanta, USA
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Beckley JT, Laguesse S, Phamluong K, Morisot N, Wegner SA, Ron D. The First Alcohol Drink Triggers mTORC1-Dependent Synaptic Plasticity in Nucleus Accumbens Dopamine D1 Receptor Neurons. J Neurosci 2016; 36:701-13. [PMID: 26791202 PMCID: PMC4719011 DOI: 10.1523/jneurosci.2254-15.2016] [Citation(s) in RCA: 71] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2015] [Revised: 11/16/2015] [Accepted: 11/24/2015] [Indexed: 01/25/2023] Open
Abstract
Early binge-like alcohol drinking may promote the development of hazardous intake. However, the enduring cellular alterations following the first experience with alcohol consumption are not fully understood. We found that the first binge-drinking alcohol session produced enduring enhancement of excitatory synaptic transmission onto dopamine D1 receptor-expressing neurons (D1+ neurons) in the nucleus accumbens (NAc) shell but not the core in mice, which required D1 receptors (D1Rs) and mechanistic target of rapamycin complex 1 (mTORC1). Furthermore, inhibition of mTORC1 activity during the first alcohol drinking session reduced alcohol consumption and preference of a subsequent drinking session. mTORC1 is critically involved in RNA-to-protein translation, and we found that the first alcohol session rapidly activated mTORC1 in NAc shell D1+ neurons and increased synaptic expression of the AMPAR subunit GluA1 and the scaffolding protein Homer. Finally, D1R stimulation alone was sufficient to activate mTORC1 in the NAc to promote mTORC1-dependent translation of the synaptic proteins GluA1 and Homer. Together, our results indicate that the first alcohol drinking session induces synaptic plasticity in NAc D1+ neurons via enhanced mTORC1-dependent translation of proteins involved in excitatory synaptic transmission that in turn drives the reinforcement learning associated with the first alcohol experience. Thus, the alcohol-dependent D1R/mTORC1-mediated increase in synaptic function in the NAc may reflect a neural imprint of alcohol's reinforcing properties, which could promote subsequent alcohol intake. Significance statement: Consuming alcohol for the first time is a learning event that drives further drinking. Here, we identified a mechanism that may underlie the reinforcing learning associated with the initial alcohol experience. We show that the first alcohol experience induces a persistent enhancement of excitatory synaptic transmission on NAc shell D1+ neurons, which is dependent on D1R and mTORC1. We also find that mTORC1 is necessary for the sustained alcohol consumption and preference across the initial drinking sessions. The first alcohol binge activates mTORC1 in NAc D1+ neurons and increases levels of synaptic proteins involved in glutamatergic signaling. Thus, the D1R/mTORC1-dependent plasticity following the first alcohol exposure may be a critical cellular component of reinforcement learning.
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Affiliation(s)
- Jacob T Beckley
- Department of Neurology, University of California, San Francisco, California 94143-0663
| | - Sophie Laguesse
- Department of Neurology, University of California, San Francisco, California 94143-0663
| | - Khanhky Phamluong
- Department of Neurology, University of California, San Francisco, California 94143-0663
| | - Nadege Morisot
- Department of Neurology, University of California, San Francisco, California 94143-0663
| | - Scott A Wegner
- Department of Neurology, University of California, San Francisco, California 94143-0663
| | - Dorit Ron
- Department of Neurology, University of California, San Francisco, California 94143-0663
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Bassareo V, Cucca F, Frau R, Di Chiara G. Differential activation of accumbens shell and core dopamine by sucrose reinforcement with nose poking and with lever pressing. Behav Brain Res 2015; 294:215-23. [PMID: 26275926 DOI: 10.1016/j.bbr.2015.08.006] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2015] [Revised: 08/06/2015] [Accepted: 08/07/2015] [Indexed: 11/30/2022]
Abstract
In order to investigate the role of modus operandi in the changes of nucleus accumbens (NAc) dopamine (DA) transmission in sucrose reinforcement, extracellular DA was monitored by microdialysis in the NAc shell and core of rats trained on a fixed-ratio 1 schedule to respond for sucrose pellets by nose poking and lever pressing respectively. After training, rats were tested on three different sessions: sucrose reinforcement, extinction and passive sucrose presentation. In rats responding by nose poking dialysate DA increased in the shell but not in the core under reinforced as well as under extinction sessions. In contrast, in rats responding by lever pressing dialysate DA increased both in the accumbens shell and core under reinforced and extinction sessions. Response non-contingent sucrose presentation increased dialysate DA in the shell and core of rats trained to respond for sucrose by nose poking as well as in those trained by lever pressing. In rats trained to respond for sucrose by nose poking on a FR5 schedule dialysate DA also increased selectively in the NAc shell during reinforced responding and in both the shell and core under passive sucrose presentation. These findings, while provide an explanation for the discrepancies existing in the literature over the responsiveness of shell and core DA in rats responding for food, are consistent with the notion that NAc shell and core DA encode different aspects of reinforcement.
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Affiliation(s)
- V Bassareo
- Department of Biomedical Sciences, University of Cagliari, Via Ospedale 72, 09124 Cagliari, Italy.
| | - F Cucca
- Department of Biomedical Sciences, University of Cagliari, Via Ospedale 72, 09124 Cagliari, Italy
| | - R Frau
- Department of Biomedical Sciences, University of Cagliari, Via Ospedale 72, 09124 Cagliari, Italy
| | - G Di Chiara
- Department of Biomedical Sciences, University of Cagliari, Via Ospedale 72, 09124 Cagliari, Italy; CNR Institute of Neuroscience, Cagliari Section, Via Ospedale 72, 09124 Cagliari, Italy.
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Bassareo V, Cucca F, Musio P, Lecca D, Frau R, Di Chiara G. Nucleus accumbens shell and core dopamine responsiveness to sucrose in rats: role of response contingency and discriminative/conditioned cues. Eur J Neurosci 2015; 41:802-9. [PMID: 25645148 DOI: 10.1111/ejn.12839] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2014] [Revised: 12/19/2014] [Accepted: 12/20/2014] [Indexed: 11/27/2022]
Abstract
This study investigated by microdialysis the role of response contingency and food-associated cues in the responsiveness of dopamine transmission in the nucleus accumbens shell and core to sucrose feeding. In naive rats, single-trial non-contingent presentation and feeding of sucrose pellets increased dialysate shell dopamine and induced full habituation of dopamine responsiveness to sucrose feeding 24 and 48 h later. In rats trained to respond for sucrose pellets on a fixed ratio 1 (FR1) schedule, dialysate dopamine increased in the shell but not in the core during active responding as well as under extinction in the presence of sucrose cues. In rats yoked to the operant rats, the presentation of sucrose cues also increased dialysate dopamine selectively in the shell. In contrast, non-contingent sucrose presentation and feeding in FR1-trained and in yoked rats increased dialysate dopamine to a similar extent in the shell and core. It is concluded that, whereas non-contingent sucrose feeding activated dopamine transmission in the shell and core, response-contingent feeding activated, without habituation, dopamine transmission selectively in the shell as a result of the action of sucrose conditioned cues. These observations are consistent with a critical role of conditioned cues acquired during training and differential activation of shell vs. core dopamine for response-contingent sucrose feeding.
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Affiliation(s)
- V Bassareo
- Department of Biomedical Sciences, University of Cagliari, Via Ospedale 72, 09124, Cagliari, Italy; National Institute of Neuroscience, University of Cagliari, Cagliari, Italy
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