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Jones JD, Arout CA, Luba R, Murugesan D, Madera G, Gorsuch L, Schusterman R, Martinez S. The influence of drug class on reward in substance use disorders. Pharmacol Biochem Behav 2024; 240:173771. [PMID: 38670466 PMCID: PMC11162950 DOI: 10.1016/j.pbb.2024.173771] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/01/2024] [Revised: 03/26/2024] [Accepted: 04/16/2024] [Indexed: 04/28/2024]
Abstract
In the United States, the societal costs associated with drug use surpass $500 billion annually. The rewarding and reinforcing properties that drive the use of these addictive substances are typically examined concerning the neurobiological effects responsible for their abuse potential. In this review, terms such as "abuse potential," "drug," and "addictive properties" are used due to their relevance to the methodological, theoretical, and conceptual framework for understanding the phenomenon of drug-taking behavior and the associated body of preclinical and clinical literature. The use of these terms is not intended to cast aspersions on individuals with substance use disorders (SUD). Understanding what motivates substance use has been a focus of SUD research for decades. Much of this corpus of work has focused on the shared effects of each drug class to increase dopaminergic transmission within the central reward pathways of the brain, or the "reward center." However, the precise influence of each drug class on dopamine signaling, and the extent thereof, differs considerably. Furthermore, the aforementioned substances have effects on several neurobiological targets that mediate and modulate their addictive properties. The current manuscript sought to review the influence of drug class on the rewarding effects of each of the major pharmacological classes of addictive drugs (i.e., psychostimulants, opioids, nicotine, alcohol, and cannabinoids). Our review suggests that even subtle differences in drug effects can result in significant variability in the subjective experience of the drug, altering rewarding and other reinforcing effects. Additionally, this review will argue that reward (i.e., the attractive and motivational property of a stimulus) alone is not sufficient to explain the abuse liability of these substances. Instead, abuse potential is best examined as a function of both positive and negative reinforcing drug effects (i.e., stimuli that the subject will work to attain and stimuli that the subject will work to end or avoid, respectively). Though reward is central to drug use, the factors that motivate and maintain drug taking are varied and complex, with much to be elucidated.
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Affiliation(s)
- Jermaine D Jones
- Division on Substance Use Disorders, Department of Psychiatry, Columbia University Vagelos College of Physicians and Surgeons, 1051 Riverside Drive, New York, NY 10032, USA.
| | - Caroline A Arout
- Division on Substance Use Disorders, Department of Psychiatry, Columbia University Vagelos College of Physicians and Surgeons, 1051 Riverside Drive, New York, NY 10032, USA
| | - Rachel Luba
- Division on Substance Use Disorders, Department of Psychiatry, Columbia University Vagelos College of Physicians and Surgeons, 1051 Riverside Drive, New York, NY 10032, USA
| | - Dillon Murugesan
- CUNY School of Medicine, 160 Convent Avenue, New York, NY 10031, USA
| | - Gabriela Madera
- Division on Substance Use Disorders, Department of Psychiatry, Columbia University Vagelos College of Physicians and Surgeons, 1051 Riverside Drive, New York, NY 10032, USA
| | - Liam Gorsuch
- Department of Psychiatry, The University of British Columbia, 430-5950 University Blvd., Vancouver V6T 1Z3, BC, Canada
| | - Rebecca Schusterman
- Division on Substance Use Disorders, Department of Psychiatry, Columbia University Vagelos College of Physicians and Surgeons, 1051 Riverside Drive, New York, NY 10032, USA
| | - Suky Martinez
- Division on Substance Use Disorders, Department of Psychiatry, Columbia University Vagelos College of Physicians and Surgeons, 1051 Riverside Drive, New York, NY 10032, USA
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Ardenkjær-Skinnerup J, Saar D, Christiansen S, Svingen T, Hadrup N, Brown KA, Emanuelli B, Kragelund BB, Ravn-Haren G, Vogel U. Effects of ethanol or ethylene glycol exposure on PPARγ and aromatase expression in adipose tissue. Biochem Biophys Rep 2024; 38:101742. [PMID: 38873224 PMCID: PMC11170351 DOI: 10.1016/j.bbrep.2024.101742] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2024] [Revised: 05/22/2024] [Accepted: 05/23/2024] [Indexed: 06/15/2024] Open
Abstract
The estrogen-synthesizing enzyme aromatase is expressed in adipose tissue where it controls the local concentration of estrogen. It has been suggested that the organic solvents ethanol and ethylene glycol can induce estrogen synthesis by inhibiting PPARγ activity. Since elevated estrogen synthesis in adipose tissue is a risk factor for breast cancer development, it is of interest to further characterize the mechanisms regulating aromatase expression. Here, we explored the mechanisms by which ethanol and ethylene glycol modulate aromatase mRNA expression and the ultimate conversion of androgens into estrogens. NMR spectroscopy revealed that ethanol and ethylene glycol influence the active state of PPARγ. An inhibitory effect on PPARγ was confirmed by adipogenesis assays and PPARγ target gene expression analysis in adipocytes. However, only ethanol increased aromatase mRNA in differentiated human adipocytes. In contrast, ethylene glycol downregulated aromatase in a PPARγ-independent manner. An animal study using female Wistar rats was conducted to assess the acute effects of ethanol and ethylene glycol on aromatase expression in adipose tissue within a physiological context. No changes in aromatase or PPARγ target gene (Adipoq and Fabp4) levels were observed in adipose tissue or ovary in response to the chemical exposures, suggesting an absence of acute PPARγ-mediated effects in these organs. The results suggest that ethanol and ethylene glycol are weak PPARγ antagonists in mouse and human adipocytes as well as in cell-free NMR spectroscopy. Both compounds seem to affect adipocyte aromatase expression in vitro, where ethanol increased aromatase expression PPARγ-dependently and ethylene glycol decreased aromatase expression independently of PPARγ. No acute effects on aromatase expression or PPARγ activity were observed in adipose tissue or ovary in rats in this study design.
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Affiliation(s)
- Jacob Ardenkjær-Skinnerup
- The National Food Institute, Technical University of Denmark, Kongens Lyngby, Denmark
- The National Research Centre for the Working Environment, Copenhagen Ø, Denmark
| | - Daniel Saar
- REPIN and Structural Biology and NMR Laboratory, Department of Biology, University of Copenhagen, Copenhagen N, Denmark
| | - Sofie Christiansen
- The National Food Institute, Technical University of Denmark, Kongens Lyngby, Denmark
| | - Terje Svingen
- The National Food Institute, Technical University of Denmark, Kongens Lyngby, Denmark
| | - Niels Hadrup
- The National Food Institute, Technical University of Denmark, Kongens Lyngby, Denmark
- The National Research Centre for the Working Environment, Copenhagen Ø, Denmark
| | - Kristy A. Brown
- Department of Medicine, Weill Cornell Medicine, New York, NY, USA
- Department of Cell Biology and Physiology, University of Kansas Medical Center, Kansas City, KS, USA
| | - Brice Emanuelli
- The Novo Nordisk Foundation Center for Basic Metabolic Research, University of Copenhagen, Copenhagen N, Denmark
| | - Birthe B. Kragelund
- REPIN and Structural Biology and NMR Laboratory, Department of Biology, University of Copenhagen, Copenhagen N, Denmark
| | - Gitte Ravn-Haren
- The National Food Institute, Technical University of Denmark, Kongens Lyngby, Denmark
| | - Ulla Vogel
- The National Food Institute, Technical University of Denmark, Kongens Lyngby, Denmark
- The National Research Centre for the Working Environment, Copenhagen Ø, Denmark
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3
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Diot A, Groth G, Blanchet S, Chervin C. Responses of animals and plants to physiological doses of ethanol: a molecular messenger of hypoxia? FEBS J 2024; 291:1102-1110. [PMID: 38232057 DOI: 10.1111/febs.17056] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2023] [Revised: 12/11/2023] [Accepted: 12/28/2023] [Indexed: 01/19/2024]
Abstract
Our viewpoint is that ethanol could act as a molecular messenger in animal and plant organisms under conditions of hypoxia or other stresses and could elicit physiological responses to such conditions. There is evidence that both animal and plant organisms have endogenous levels of ethanol, but reports on the changes induced by this alcohol at physiological levels are sparse. Studies have shown that ethanol has different effects on cell metabolism at low and high concentrations, resembling a hormetic response. Further studies have addressed the potential cellular and molecular mechanisms used by organisms to sense changes in physiological concentrations of ethanol. This article summarizes the possible mechanisms by which ethanol may be sensed, particularly at the cell membrane level. Our analysis shows that current knowledge on this subject is limited. More research is required on the effects of ethanol at very low doses, in plants and animals at both molecular and physiological levels. We believe that further research on this topic could lead to new discoveries in physiology and may even help us understand metabolic adjustments related to climate change. As temperatures rise more frequently, dissolved oxygen levels drop, leading to hypoxic conditions and consequently, an increase in cellular ethanol levels.
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Affiliation(s)
- Alice Diot
- Laboratoire de Recherche en Sciences Végétales (UMR5546), Université de Toulouse, CNRS, UPS, Toulouse-INP, Castanet-Tolosan, France
- CNRS, Station d'Ecologie Théorique et Expérimentale (UAR 2029), Moulis, France
| | - Georg Groth
- Institute of Biochemical Plant Physiology, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
- Bioeconomy Science Center (BioSC), Jülich, Germany
| | - Simon Blanchet
- CNRS, Station d'Ecologie Théorique et Expérimentale (UAR 2029), Moulis, France
| | - Christian Chervin
- Laboratoire de Recherche en Sciences Végétales (UMR5546), Université de Toulouse, CNRS, UPS, Toulouse-INP, Castanet-Tolosan, France
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Okhuarobo A, Kreifeldt M, Gandhi PJ, Lopez C, Martinez B, Fleck K, Bajo M, Bhattacharyya P, Dopico AM, Roberto M, Roberts AJ, Homanics GE, Contet C. Ethanol's interaction with BK channel α subunit residue K361 does not mediate behavioral responses to alcohol in mice. Mol Psychiatry 2024; 29:529-542. [PMID: 38135755 PMCID: PMC11116116 DOI: 10.1038/s41380-023-02346-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/02/2023] [Accepted: 11/27/2023] [Indexed: 12/24/2023]
Abstract
Large conductance potassium (BK) channels are among the most sensitive molecular targets of ethanol and genetic variations in the channel-forming α subunit have been nominally associated with alcohol use disorders. However, whether the action of ethanol at BK α influences the motivation to drink alcohol remains to be determined. To address this question, we first tested the effect of systemically administered BK channel modulators on voluntary alcohol consumption in C57BL/6J males. Penitrem A (blocker) exerted dose-dependent effects on moderate alcohol intake, while paxilline (blocker) and BMS-204352 (opener) were ineffective. Because pharmacological manipulations are inherently limited by non-specific effects, we then sought to investigate the behavioral relevance of ethanol's direct interaction with BK α by introducing in the mouse genome a point mutation known to render BK channels insensitive to ethanol while preserving their physiological function. The BK α K361N substitution prevented ethanol from reducing spike threshold in medial habenula neurons. However, it did not alter acute responses to ethanol in vivo, including ataxia, sedation, hypothermia, analgesia, and conditioned place preference. Furthermore, the mutation did not have reproducible effects on alcohol consumption in limited, continuous, or intermittent access home cage two-bottle choice paradigms conducted in both males and females. Notably, in contrast to previous observations made in mice missing BK channel auxiliary β subunits, the BK α K361N substitution had no significant impact on ethanol intake escalation induced by chronic intermittent alcohol vapor inhalation. It also did not affect the metabolic and locomotor consequences of chronic alcohol exposure. Altogether, these data suggest that the direct interaction of ethanol with BK α does not mediate the alcohol-related phenotypes examined here in mice.
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Affiliation(s)
- Agbonlahor Okhuarobo
- The Scripps Research Institute, Department of Molecular Medicine, La Jolla, CA, USA
| | - Max Kreifeldt
- The Scripps Research Institute, Department of Molecular Medicine, La Jolla, CA, USA
| | - Pauravi J Gandhi
- The Scripps Research Institute, Department of Molecular Medicine, La Jolla, CA, USA
| | - Catherine Lopez
- The Scripps Research Institute, Department of Molecular Medicine, La Jolla, CA, USA
| | - Briana Martinez
- The Scripps Research Institute, Department of Molecular Medicine, La Jolla, CA, USA
| | - Kiera Fleck
- The Scripps Research Institute, Department of Molecular Medicine, La Jolla, CA, USA
| | - Michal Bajo
- The Scripps Research Institute, Department of Molecular Medicine, La Jolla, CA, USA
| | | | - Alex M Dopico
- University of Tennessee Health Science Center, Department of Pharmacology, Addiction Science, and Toxicology, Memphis, TN, USA
| | - Marisa Roberto
- The Scripps Research Institute, Department of Molecular Medicine, La Jolla, CA, USA
| | - Amanda J Roberts
- The Scripps Research Institute, Animals Models Core Facility, La Jolla, CA, USA
| | - Gregg E Homanics
- University of Pittsburgh, Department of Anesthesiology and Perioperative Medicine, Pittsburgh, PA, USA
| | - Candice Contet
- The Scripps Research Institute, Department of Molecular Medicine, La Jolla, CA, USA.
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Arzua T, Yan Y, Liu X, Dash RK, Liu QS, Bai X. Synaptic and mitochondrial mechanisms behind alcohol-induced imbalance of excitatory/inhibitory synaptic activity and associated cognitive and behavioral abnormalities. Transl Psychiatry 2024; 14:51. [PMID: 38253552 PMCID: PMC10803756 DOI: 10.1038/s41398-024-02748-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/10/2023] [Revised: 01/02/2024] [Accepted: 01/08/2024] [Indexed: 01/24/2024] Open
Abstract
Alcohol consumption during pregnancy can significantly impact the brain development of the fetus, leading to long-term cognitive and behavioral problems. However, the underlying mechanisms are not well understood. In this study, we investigated the acute and chronic effects of binge-like alcohol exposure during the third trimester equivalent in postnatal day 7 (P7) mice on brain cell viability, synapse activity, cognitive and behavioral performance, and gene expression profiles at P60. Our results showed that alcohol exposure caused neuroapoptosis in P7 mouse brains immediately after a 6-hour exposure. In addition, P60 mice exposed to alcohol during P7 displayed impaired learning and memory abilities and anxiety-like behaviors. Electrophysiological analysis of hippocampal neurons revealed an excitatory/inhibitory imbalance in alcohol-treated P60 mice compared to controls, with decreased excitation and increased inhibition. Furthermore, our bioinformatic analysis of 376 dysregulated genes in P60 mouse brains following alcohol exposure identified 50 synapse-related and 23 mitochondria-related genes. These genes encoded proteins located in various parts of the synapse, synaptic cleft, extra-synaptic space, synaptic membranes, or mitochondria, and were associated with different biological processes and functions, including the regulation of synaptic transmission, transport, synaptic vesicle cycle, metabolism, synaptogenesis, mitochondrial activity, cognition, and behavior. The dysregulated synapse and mitochondrial genes were predicted to interact in overlapping networks. Our findings suggest that altered synaptic activities and signaling networks may contribute to alcohol-induced long-term cognitive and behavioral impairments in mice, providing new insights into the underlying synaptic and mitochondrial molecular mechanisms and potential neuroprotective strategies.
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Affiliation(s)
- Thiago Arzua
- Department of Cell Biology, Neurobiology & Anatomy, Medical College of Wisconsin, Milwaukee, WI, 53226, USA
| | - Yasheng Yan
- Department of Cell Biology, Neurobiology & Anatomy, Medical College of Wisconsin, Milwaukee, WI, 53226, USA
| | - Xiaojie Liu
- Department of Pharmacology, Medical College of Wisconsin, Milwaukee, 53226, WI, USA
| | - Ranjan K Dash
- Department of Biomedical Engineering, Medical College of Wisconsin, Milwaukee, 53226, WI, USA
| | - Qing-Song Liu
- Department of Pharmacology, Medical College of Wisconsin, Milwaukee, 53226, WI, USA
| | - Xiaowen Bai
- Department of Cell Biology, Neurobiology & Anatomy, Medical College of Wisconsin, Milwaukee, WI, 53226, USA.
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Lee SH, Shnitko TA, Hsu LM, Broadwater MA, Sardinas M, Wang TWW, Robinson DL, Vetreno RP, Crews FT, Shih YYI. Acute alcohol induces greater dose-dependent increase in the lateral cortical network functional connectivity in adult than adolescent rats. ADDICTION NEUROSCIENCE 2023; 7:100105. [PMID: 37576436 PMCID: PMC10421607 DOI: 10.1016/j.addicn.2023.100105] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/15/2023]
Abstract
Alcohol misuse and, particularly adolescent drinking, is a major public health concern. While evidence suggests that adolescent alcohol use affects frontal brain regions that are important for cognitive control over behavior little is known about how acute alcohol exposure alters large-scale brain networks and how sex and age may moderate such effects. Here, we employ a recently developed functional magnetic resonance imaging (fMRI) protocol to acquire rat brain functional connectivity data and use an established analytical pipeline to examine the effect of sex, age, and alcohol dose on connectivity within and between three major rodent brain networks: defaul mode, salience, and lateral cortical network. We identify the intra- and inter-network connectivity differences and establish moderation models to reveal significant influences of age on acute alcohol-induced lateral cortical network connectivity. Through this work, we make brain-wide isotropic fMRI data with acute alcohol challenge publicly available, with the hope to facilitate future discovery of brain regions/circuits that are causally relevant to the impact of acute alcohol use.
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Affiliation(s)
- Sung-Ho Lee
- Center for Animal MRI, University of North Carolina, Chapel Hill, NC, USA
- Biomedical Research Imaging Center, University of North Carolina, Chapel Hill, NC, USA
- Department of Neurology, University of North Carolina, Chapel Hill, NC, USA
- Bowles Center for Alcohol Studies University of North Carolina, Chapel Hill, NC, USA
| | - Tatiana A. Shnitko
- Center for Animal MRI, University of North Carolina, Chapel Hill, NC, USA
- Biomedical Research Imaging Center, University of North Carolina, Chapel Hill, NC, USA
- Department of Neurology, University of North Carolina, Chapel Hill, NC, USA
| | - Li-Ming Hsu
- Center for Animal MRI, University of North Carolina, Chapel Hill, NC, USA
- Biomedical Research Imaging Center, University of North Carolina, Chapel Hill, NC, USA
- Department of Neurology, University of North Carolina, Chapel Hill, NC, USA
| | - Margaret A. Broadwater
- Center for Animal MRI, University of North Carolina, Chapel Hill, NC, USA
- Biomedical Research Imaging Center, University of North Carolina, Chapel Hill, NC, USA
- Department of Neurology, University of North Carolina, Chapel Hill, NC, USA
- Bowles Center for Alcohol Studies University of North Carolina, Chapel Hill, NC, USA
| | - Mabelle Sardinas
- Center for Animal MRI, University of North Carolina, Chapel Hill, NC, USA
- Biomedical Research Imaging Center, University of North Carolina, Chapel Hill, NC, USA
- Department of Neurology, University of North Carolina, Chapel Hill, NC, USA
| | - Tzu-Wen Winnie Wang
- Center for Animal MRI, University of North Carolina, Chapel Hill, NC, USA
- Biomedical Research Imaging Center, University of North Carolina, Chapel Hill, NC, USA
- Department of Neurology, University of North Carolina, Chapel Hill, NC, USA
| | - Donita L. Robinson
- Bowles Center for Alcohol Studies University of North Carolina, Chapel Hill, NC, USA
- Department of Psychiatry, University of North Carolina, Chapel Hill, NC, USA
| | - Ryan P. Vetreno
- Bowles Center for Alcohol Studies University of North Carolina, Chapel Hill, NC, USA
- Department of Psychiatry, University of North Carolina, Chapel Hill, NC, USA
| | - Fulton T. Crews
- Bowles Center for Alcohol Studies University of North Carolina, Chapel Hill, NC, USA
- Department of Psychiatry, University of North Carolina, Chapel Hill, NC, USA
- Department of Pharmacology, University of North Carolina, Chapel Hill, NC, USA
| | - Yen-Yu Ian Shih
- Center for Animal MRI, University of North Carolina, Chapel Hill, NC, USA
- Biomedical Research Imaging Center, University of North Carolina, Chapel Hill, NC, USA
- Department of Neurology, University of North Carolina, Chapel Hill, NC, USA
- Bowles Center for Alcohol Studies University of North Carolina, Chapel Hill, NC, USA
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Bi-directional modulation of hyperpolarization-activated cation currents (I h) by ethanol in rat hippocampal CA3 pyramidal neurons. Neuropharmacology 2023; 227:109423. [PMID: 36690323 DOI: 10.1016/j.neuropharm.2023.109423] [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: 09/09/2022] [Revised: 01/12/2023] [Accepted: 01/15/2023] [Indexed: 01/22/2023]
Abstract
It is widely acknowledged that ethanol (EtOH) can alter many neuronal functions, including synaptic signaling, firing discharge, and membrane excitability, through its interaction with multiple membrane proteins and intracellular pathways. Previous work has demonstrated that EtOH enhances the firing rate of hippocampal GABAergic interneurons and thus the presynaptic GABA release at CA1 and CA3 inhibitory synapses through a positive modulation of the hyperpolarization-activated cyclic nucleotide-gated cation (HCN) channels. Activation of HCN channels produce an inward current, commonly called Ih, which plays an essential role in generating/regulating specific neuronal activities in GABAergic interneurons and principal glutamatergic pyramidal neurons such as those in the CA3 subregion. Since the direct effect of EtOH on HCN channels expressed in CA3 pyramidal neurons was not thoroughly elucidated, we investigated the possible interaction between EtOH and HCN channels and the impact on excitability and postsynaptic integration of these neurons. Patch-clamp recordings were performed in single CA3 pyramidal neurons from acute male rat coronal hippocampal slices. Our results show that EtOH modulates HCN-mediated Ih in a concentration-dependent and bi-directional manner, with a positive modulation at lower (20 mM) and an inhibitory action at higher (60-80 mM) concentrations. The modulation of Ih by EtOH was mimicked by forskolin, antagonized by different drugs that selectively interfere with the AC/cAMP/PKA intracellular pathway, as well as by the selective HCN inhibitor ZD7288. Altogether, these data further support the evidence that HCN channels may represent an important molecular target through which EtOH may regulate neuronal activity.
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Wang L, Wang R, Zheng Q, Yao X, Zhang C, Fu S, Wei Z, Yun K, Guo Z. Simulating dynamic interaction between diazepam and ethanol targeting the GABA A receptor via in silico model. Neurotoxicology 2023; 95:136-143. [PMID: 36736785 DOI: 10.1016/j.neuro.2023.01.012] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2022] [Revised: 01/30/2023] [Accepted: 01/31/2023] [Indexed: 02/05/2023]
Abstract
Combined diazepam-ethanol poisoning is common in forensic toxicology. Both diazepam and ethanol can inhibit the central nervous system via the γ-aminobutyric acid (GABA) ligand gated chloride ion channel, GABAA Receptor (GABAAR). As the common target of diazepam and ethanol, whether GABAAR is the key target of their combined action remains unclear. This study aimed to explore their interaction based on the synergistic mechanisms between diazepam and ethanol targeting the GABAAR. Four models were built in silico based on the crystal structure of GABAAR. Molecular dynamic processes of the four models were simulated by the GPU-accelerated pmemd.cuda program in the Amber18 package. Results showed that ethanol inclined to combine the adjacent GABA or diazepam sites, minimized fluctuations of the root-mean-square deviation (RMSD) in the molecular dynamic process of GABA or diazepam binding the GABAAR, and increased the release of binding energy of GABA or diazepam binding the GABAAR. Results also showed that diazepam had less effect on the RMSD fluctuation or the binding energy release of GABA binding GABAAR. The formation of complex of diazepam and GABAAR could minimize the RMSD fluctuation and increase binding energy release of ethanol binding GABAAR. Thus, ethanol, bridging GABA and diazepam, could strengthen the complex of GABA binding the GABAAR, as well as the complex of diazepam binding the GABAAR. However, whether diazepam binds GABAAR or not, it cannot affect GABA binding the GABAAR; and yet the complex of diazepam and GABAAR can stabilize the complex of ethanol and GABAAR.
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Affiliation(s)
- Lele Wang
- School of Forensic Medicine, Shanxi Medical University, Key Laboratory of Forensic Toxicology, Ministry of Public Security, the People's Republic of China, Jinzhong 030600, China
| | - Ruili Wang
- School of Forensic Medicine, Shanxi Medical University, Key Laboratory of Forensic Toxicology, Ministry of Public Security, the People's Republic of China, Jinzhong 030600, China; School of Pharmacy, Shanxi Medical University, Jinzhong 030600, China
| | - Qian Zheng
- School of Forensic Medicine, Shanxi Medical University, Key Laboratory of Forensic Toxicology, Ministry of Public Security, the People's Republic of China, Jinzhong 030600, China; School of Pharmacy, Shanxi Medical University, Jinzhong 030600, China
| | - Xiukun Yao
- School of Forensic Medicine, Shanxi Medical University, Key Laboratory of Forensic Toxicology, Ministry of Public Security, the People's Republic of China, Jinzhong 030600, China
| | - Chao Zhang
- School of Forensic Medicine, Shanxi Medical University, Key Laboratory of Forensic Toxicology, Ministry of Public Security, the People's Republic of China, Jinzhong 030600, China
| | - Shanlin Fu
- School of Forensic Medicine, Shanxi Medical University, Key Laboratory of Forensic Toxicology, Ministry of Public Security, the People's Republic of China, Jinzhong 030600, China; University of Technology Sydney, Australia
| | - Zhiwen Wei
- School of Forensic Medicine, Shanxi Medical University, Key Laboratory of Forensic Toxicology, Ministry of Public Security, the People's Republic of China, Jinzhong 030600, China.
| | - Keming Yun
- School of Forensic Medicine, Shanxi Medical University, Key Laboratory of Forensic Toxicology, Ministry of Public Security, the People's Republic of China, Jinzhong 030600, China.
| | - Zhongyuan Guo
- School of Forensic Medicine, Shanxi Medical University, Key Laboratory of Forensic Toxicology, Ministry of Public Security, the People's Republic of China, Jinzhong 030600, China.
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9
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Popova S, Charness ME, Burd L, Crawford A, Hoyme HE, Mukherjee RAS, Riley EP, Elliott EJ. Fetal alcohol spectrum disorders. Nat Rev Dis Primers 2023; 9:11. [PMID: 36823161 DOI: 10.1038/s41572-023-00420-x] [Citation(s) in RCA: 58] [Impact Index Per Article: 58.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 01/16/2023] [Indexed: 02/25/2023]
Abstract
Alcohol readily crosses the placenta and may disrupt fetal development. Harm from prenatal alcohol exposure (PAE) is determined by the dose, pattern, timing and duration of exposure, fetal and maternal genetics, maternal nutrition, concurrent substance use, and epigenetic responses. A safe dose of alcohol use during pregnancy has not been established. PAE can cause fetal alcohol spectrum disorders (FASD), which are characterized by neurodevelopmental impairment with or without facial dysmorphology, congenital anomalies and poor growth. FASD are a leading preventable cause of birth defects and developmental disability. The prevalence of FASD in 76 countries is >1% and is high in individuals living in out-of-home care or engaged in justice and mental health systems. The social and economic effects of FASD are profound, but the diagnosis is often missed or delayed and receives little public recognition. Future research should be informed by people living with FASD and be guided by cultural context, seek consensus on diagnostic criteria and evidence-based treatments, and describe the pathophysiology and lifelong effects of FASD. Imperatives include reducing stigma, equitable access to services, improved quality of life for people with FASD and FASD prevention in future generations.
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Affiliation(s)
- Svetlana Popova
- Institute for Mental Health Policy Research, Centre for Addiction and Mental Health, University of Toronto, Toronto, Ontario, Canada.
| | - Michael E Charness
- VA Boston Healthcare System, West Roxbury, MA, USA.,Department of Neurology, Harvard Medical School, Boston, MA, USA.,Department of Neurology, Boston University Chobanian & Avedisian School of Medicine, Boston, MA, USA.,Department of Neurology, Brigham and Women's Hospital, Boston, MA, USA
| | - Larry Burd
- North Dakota Fetal Alcohol Syndrome Center, Department of Pediatrics, University of North Dakota School of Medicine and Health Sciences, Pediatric Therapy Services, Altru Health System, Grand Forks, ND, USA
| | - Andi Crawford
- Faculty of Medical and Health Sciences, University of Auckland, Auckland, New Zealand
| | - H Eugene Hoyme
- Sanford Children's Genomic Medicine Consortium, Sanford Health, and University of South Dakota Sanford School of Medicine, Sioux Falls, SD, USA
| | - Raja A S Mukherjee
- National UK FASD Clinic, Surrey and Borders Partnership NHS Foundation Trust, Redhill, Surrey, UK
| | - Edward P Riley
- Center for Behavioral Teratology, San Diego State University, San Diego, CA, USA
| | - Elizabeth J Elliott
- Faculty of Medicine and Health, University of Sydney, Sydney, New South Wales, Australia.,New South Wales FASD Assessment Service, CICADA Centre for Care and Intervention for Children and Adolescents affected by Drugs and Alcohol, Sydney Children's Hospitals Network, Westmead, Sydney, New South Wales, Australia
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10
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Mack ML, Huang W, Chang SL. Involvement of TRPM7 in Alcohol-Induced Damage of the Blood-Brain Barrier in the Presence of HIV Viral Proteins. Int J Mol Sci 2023; 24:1910. [PMID: 36768230 PMCID: PMC9916124 DOI: 10.3390/ijms24031910] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2022] [Revised: 12/22/2022] [Accepted: 01/14/2023] [Indexed: 01/21/2023] Open
Abstract
Ethanol (EtOH) exerts its effects through various protein targets, including transient receptor potential melastatin 7 (TRPM7) channels, which play an essential role in cellular homeostasis. We demonstrated that TRPM7 is expressed in rat brain microvascular endothelial cells (rBMVECs), the major cellular component of the blood-brain barrier (BBB). Heavy alcohol drinking is often associated with HIV infection, however mechanisms underlying alcohol-induced BBB damage and HIV proteins, are not fully understood. We utilized the HIV-1 transgenic (HIV-1Tg) rat to mimic HIV-1 patients on combination anti-retroviral therapy (cART) and demonstrated TRPM7 expression in rBMVECs wass lower in adolescent HIV-1Tg rats compared to control animals, however control and HIV-1Tg rats expressed similar levels at 9 weeks, indicating persistent presence of HIV-1 proteins delayed TRPM7 expression. Binge exposure to EtOH (binge EtOH) decreased TRPM7 expression in control rBMVECs in a concentration-dependent manner, and abolished TRPM7 expression in HIV-1Tg rats. In human BMVECs (hBMVECs), TRPM7 expression was downregulated after treatment with EtOH, HIV-1 proteins, and in combination. Next, we constructed in vitro BBB models using BMVECs and found TRPM7 antagonists enhanced EtOH-mediated BBB integrity changes. Our study demonstrated alcohol decreased TRPM7 expression, whereby TRPM7 could be involved in the mechanisms underlying BBB alcohol-induced damage in HIV-1 patients on cART.
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Affiliation(s)
- Michelle L. Mack
- Institute of NeuroImmune Pharmacology, Seton Hall University, South Orange, NJ 07079, USA
- Department of Biological Sciences, Seton Hall University, South Orange, NJ 07079, USA
| | - Wenfei Huang
- Institute of NeuroImmune Pharmacology, Seton Hall University, South Orange, NJ 07079, USA
- Department of Biological Sciences, Seton Hall University, South Orange, NJ 07079, USA
| | - Sulie L. Chang
- Institute of NeuroImmune Pharmacology, Seton Hall University, South Orange, NJ 07079, USA
- Department of Biological Sciences, Seton Hall University, South Orange, NJ 07079, USA
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11
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Bach P, de Timary P, Gründer G, Cumming P. Molecular Imaging Studies of Alcohol Use Disorder. Curr Top Behav Neurosci 2023. [PMID: 36639552 DOI: 10.1007/7854_2022_414] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Alcohol use disorder (AUD) is a serious public health problem in many countries, bringing a gamut of health risks and impairments to individuals and a great burden to society. Despite the prevalence of a disease model of AUD, the current pharmacopeia does not present reliable treatments for AUD; approved treatments are confined to a narrow spectrum of medications engaging inhibitory γ-aminobutyric acid (GABA) neurotransmission and possibly excitatory N-methyl-D-aspartate (NMDA) receptors, and opioid receptor antagonists. Molecular imaging with positron emission tomography (PET) and single-photon emission computed tomography (SPECT) can open a window into the living brain and has provided diverse insights into the pathology of AUD. In this narrative review, we summarize the state of molecular imaging findings on the pharmacological action of ethanol and the neuropathological changes associated with AUD. Laboratory and preclinical imaging results highlight the interactions between ethanol and GABA A-type receptors (GABAAR), but the interpretation of such results is complicated by subtype specificity. An abundance of studies with the glucose metabolism tracer fluorodeoxyglucose (FDG) concur in showing cerebral hypometabolism after ethanol challenge, but there is relatively little data on long-term changes in AUD. Alcohol toxicity evokes neuroinflammation, which can be tracked using PET with ligands for the microglial marker translocator protein (TSPO). Several PET studies show reversible increases in TSPO binding in AUD individuals, and preclinical results suggest that opioid-antagonists can rescue from these inflammatory responses. There are numerous PET/SPECT studies showing changes in dopaminergic markers, generally consistent with an impairment in dopamine synthesis and release among AUD patients, as seen in a number of other addictions; this may reflect the composite of an underlying deficiency in reward mechanisms that predisposes to AUD, in conjunction with acquired alterations in dopamine signaling. There is little evidence for altered serotonin markers in AUD, but studies with opioid receptor ligands suggest a specific up-regulation of the μ-opioid receptor subtype. Considerable heterogeneity in drinking patterns, gender differences, and the variable contributions of genetics and pre-existing vulnerability traits present great challenges for charting the landscape of molecular imaging in AUD.
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Affiliation(s)
- Patrick Bach
- Department of Addictive Behavior and Addiction Medicine, Central Institute of Mental Health, Heidelberg University, Mannheim, Germany.
| | - Philippe de Timary
- Department of Adult Psychiatry, Cliniques Universitaires Saint-Luc and Institute of Neuroscience, Université Catholique de Louvain, Brussels, Belgium
| | - Gerhard Gründer
- Department of Molecular Neuroimaging, Central Institute of Mental Health, Heidelberg University, Mannheim, Germany
| | - Paul Cumming
- Department of Nuclear Medicine, Bern University Hospital, Bern, Switzerland
- School of Psychology and Counselling, Queensland University of Technology, Brisbane, QLD, Australia
- International Centre for Education and Research in Neuropsychiatry (ICERN), Samara State Medical University, Samara, Russia
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12
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Alcohol Withdrawal and the Associated Mood Disorders-A Review. Int J Mol Sci 2022; 23:ijms232314912. [PMID: 36499240 PMCID: PMC9738481 DOI: 10.3390/ijms232314912] [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: 10/17/2022] [Accepted: 11/02/2022] [Indexed: 11/30/2022] Open
Abstract
Recreational use of alcohol is a social norm in many communities worldwide. Alcohol use in moderation brings pleasure and may protect the cardiovascular system. However, excessive alcohol consumption or alcohol abuse are detrimental to one's health. Three million deaths due to excessive alcohol consumption were reported by the World Health Organization. Emerging evidence also revealed the danger of moderate consumption, which includes the increased risk to cancer. Alcohol abuse and periods of withdrawal have been linked to depression and anxiety. Here, we present the effects of alcohol consumption (acute and chronic) on important brain structures-the frontal lobe, the temporal lobe, the limbic system, and the cerebellum. Apart from this, we also present the link between alcohol abuse and withdrawal and mood disorders in this review, thus drawing a link to oxidative stress. In addition, we also discuss the positive impacts of some pharmacotherapies used. Due to the ever-rising demands of life, the cycle between alcohol abuse, withdrawal, and mood disorders may be a never-ending cycle of destruction. Hence, through this review, we hope that we can emphasise the importance and urgency of managing this issue with the appropriate approaches.
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13
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Fish KN, Joffe ME. Targeting prefrontal cortex GABAergic microcircuits for the treatment of alcohol use disorder. Front Synaptic Neurosci 2022; 14:936911. [PMID: 36105666 PMCID: PMC9465392 DOI: 10.3389/fnsyn.2022.936911] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2022] [Accepted: 07/27/2022] [Indexed: 11/17/2022] Open
Abstract
Developing novel treatments for alcohol use disorders (AUDs) is of paramount importance for improving patient outcomes and alleviating the suffering related to the disease. A better understanding of the molecular and neurocircuit mechanisms through which alcohol alters brain function will be instrumental in the rational development of new efficacious treatments. Clinical studies have consistently associated the prefrontal cortex (PFC) function with symptoms of AUDs. Population-level analyses have linked the PFC structure and function with heavy drinking and/or AUD diagnosis. Thus, targeting specific PFC cell types and neural circuits holds promise for the development of new treatments. Here, we overview the tremendous diversity in the form and function of inhibitory neuron subtypes within PFC and describe their therapeutic potential. We then summarize AUD population genetics studies, clinical neurophysiology findings, and translational neuroscience discoveries. This study collectively suggests that changes in fast transmission through PFC inhibitory microcircuits are a central component of the neurobiological effects of ethanol and the core symptoms of AUDs. Finally, we submit that there is a significant and timely need to examine sex as a biological variable and human postmortem brain tissue to maximize the efforts in translating findings to new clinical treatments.
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Affiliation(s)
| | - Max E. Joffe
- Translational Neuroscience Program, Department of Psychiatry, University of Pittsburgh, Pittsburgh, PA, United States
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14
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Leroy C, Saba W. Contribution of TSPO imaging in the understanding of the state of gliosis in substance use disorders. Eur J Nucl Med Mol Imaging 2021; 49:186-200. [PMID: 34041563 DOI: 10.1007/s00259-021-05408-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2021] [Accepted: 05/10/2021] [Indexed: 12/17/2022]
Abstract
PURPOSE Recent research in last years in substance use disorders (SUD) synthesized a proinflammatory hypothesis of SUD based on reported pieces of evidence of non-neuronal central immune signalling pathways modulated by drug of abuse and that contribute to their pharmacodynamic actions. Positron emission tomography has been shown to be a precious imaging technique to study in vivo neurochemical processes involved in SUD and to highlight the central immune signalling actions of drugs of abuse. METHODS In this review, we investigate the contribution of the central immune system, with a particular focus on translocator protein 18 kDa (TSPO) imaging, associated with a series of drugs involved in substance use disorders (SUD) specifically alcohol, opioids, tobacco, methamphetamine, cocaine, and cannabis. RESULTS The large majority of preclinical and clinical studies presented in this review converges towards SUD modulation of the neuroimmune responses and TSPO expression and speculated a pivotal positioning in the pathogenesis of SUD. However, some contradictions concerning the same drug or between preclinical and clinical studies make it difficult to draw a clear picture about the significance of glial state in SUD. DISCUSSION Significant disparities in clinical and biological characteristics are present between investigated populations among studies. Heterogeneity in genetic factors and other clinical co-morbidities, difficult to be reproduced in animal models, may affect findings. On the other hand, technical aspects including study designs, radioligand limitations, or PET imaging quantification methods could impact the study results and should be considered to explain discrepancies in outcomes. CONCLUSION The supposed neuroimmune component of SUD provides new therapeutic approaches in the prediction and treatment of SUD pointing to the central immune signalling.
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Affiliation(s)
- Claire Leroy
- Université Paris-Saclay, CEA, CNRS, Inserm, BioMaps, Service Hospitalier Frédéric Joliot, 4 place du général Leclerc, 91401, Orsay, France
| | - Wadad Saba
- Université Paris-Saclay, CEA, CNRS, Inserm, BioMaps, Service Hospitalier Frédéric Joliot, 4 place du général Leclerc, 91401, Orsay, France.
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15
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Alleyne J, Dopico AM. Alcohol Use Disorders and Their Harmful Effects on the Contractility of Skeletal, Cardiac and Smooth Muscles. ADVANCES IN DRUG AND ALCOHOL RESEARCH 2021; 1:10011. [PMID: 35169771 PMCID: PMC8843239 DOI: 10.3389/adar.2021.10011] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/13/2021] [Accepted: 09/21/2021] [Indexed: 06/14/2023]
Abstract
Alcohol misuse has deleterious effects on personal health, family, societal units, and global economies. Moreover, alcohol misuse usually leads to several diseases and conditions, including alcoholism, which is a chronic condition and a form of addiction. Alcohol misuse, whether as acute intoxication or alcoholism, adversely affects skeletal, cardiac and/or smooth muscle contraction. Ethanol (ethyl alcohol) is the main effector of alcohol-induced dysregulation of muscle contractility, regardless of alcoholic beverage type or the ethanol metabolite (with acetaldehyde being a notable exception). Ethanol, however, is a simple and "promiscuous" ligand that affects many targets to mediate a single biological effect. In this review, we firstly summarize the processes of excitation-contraction coupling and calcium homeostasis which are critical for the regulation of contractility in all muscle types. Secondly, we present the effects of acute and chronic alcohol exposure on the contractility of skeletal, cardiac, and vascular/ nonvascular smooth muscles. Distinctions are made between in vivo and in vitro experiments, intoxicating vs. sub-intoxicating ethanol levels, and human subjects vs. animal models. The differential effects of alcohol on biological sexes are also examined. Lastly, we show that alcohol-mediated disruption of muscle contractility, involves a wide variety of molecular players, including contractile proteins, their regulatory factors, membrane ion channels and pumps, and several signaling molecules. Clear identification of these molecular players constitutes a first step for a rationale design of pharmacotherapeutics to prevent, ameliorate and/or reverse the negative effects of alcohol on muscle contractility.
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Affiliation(s)
| | - Alex M. Dopico
- Department of Pharmacology, Addiction Science, and Toxicology, College of Medicine, The University of Tennessee Health Science Center, Memphis, TN, United States
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16
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Developmental ethanol exposure causes central nervous system dysfunction and may slow the aging process in a Drosophila model of fetal alcohol spectrum disorder. Alcohol 2021; 94:65-73. [PMID: 33961967 DOI: 10.1016/j.alcohol.2021.03.006] [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: 06/05/2020] [Revised: 03/25/2021] [Accepted: 03/31/2021] [Indexed: 11/21/2022]
Abstract
Alcohol is a known teratogen, and developmental exposure to ethanol results in fetal alcohol spectrum disorder (FASD). Children born with FASD can exhibit a range of symptoms including low birth weight, microcephaly, and neurobehavioral problems. Treatment of patients with FASD is estimated to cost 4 billion dollars per year in the United States alone, and 2 million dollars per affected individual's lifetime. We have established Drosophila melanogaster as a model organism for the study of FASD. Here we report that mutations in Dementin (Dmtn), the Drosophila ortholog of the Alzheimer's disease-associated protein TMCC2, convey sensitivity to developmental ethanol exposure, and provide evidence that Dmtn expression is disrupted by ethanol. In addition, we find that flies reared on ethanol exhibit mild climbing defects suggestive of neurodegeneration. Surprisingly, our data also suggest that flies reared on ethanol age more slowly than control animals, and we find that a number of slow-aging mutants are sensitive to developmental ethanol exposure. Finally, we find that flies reared on ethanol showed a persistent upregulation of genes encoding antioxidant enzymes, which may contribute to a reduced rate of central nervous system aging. Thus, in addition to the well-documented negative effects of developmental alcohol exposure on the nervous system, there may be a previously unsuspected neuroprotective effect in adult animals.
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17
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Jin S, Cinar R, Hu X, Lin Y, Luo G, Lovinger DM, Zhang Y, Zhang L. Spinal astrocyte aldehyde dehydrogenase-2 mediates ethanol metabolism and analgesia in mice. Br J Anaesth 2021; 127:296-309. [PMID: 33934892 PMCID: PMC8362281 DOI: 10.1016/j.bja.2021.02.035] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2020] [Revised: 02/10/2021] [Accepted: 02/25/2021] [Indexed: 01/14/2023] Open
Abstract
BACKGROUND Little is known about the targets in the CNS that mediate ethanol analgesia. This study explores the role of spinal astrocyte aldehyde dehydrogenase-2 (ALDH2), a key ethanol-metabolising enzyme, in the analgesic effects of ethanol in mice. METHODS Astrocyte and hepatocyte ALHD2-deficient mice were generated and tested in acute and chronic pain models. Cell-type-specific distribution of ALDH2 was analysed by RNA in situ hybridisation in spinal slices from astrocytic ALDH2-deficient mice and their wild-type littermates. Spinal ethanol metabolites and γ-aminobutyric acid (GABA) content were measured using gas chromatography/mass spectrometry and liquid chromatography/mass spectrometry. RESULTS ALDH2 mRNA was expressed in both astrocytes and neurones in spinal cord slices. Astrocyte ALDH2-deficient mice had decreased expression of ALDH2 mRNA in astrocytes, but not in neurones. Astrocyte ALDH2 deficiency inhibited ethanol-derived acetate, but not acetaldehyde content in spinal cord tissues. Depletion of spinal astrocyte ALDH2 selectively inhibited ethanol-induced anti-nociceptive effect, but not the effect of ethanol, on motor function. Astrocyte ALDH2 deficiency abolished ethanol-induced GABA elevation. The ethanol metabolite acetate produced anti-nociception and increased GABA synthesis in a manner similar to ethanol. I.T. delivery of either GABAA or GABAB receptor antagonists prevented ethanol and acetate-induced analgesia. CONCLUSIONS These findings provide evidence that ALDH2 in spinal astrocytes mediates spinal ethanol metabolism and ethanol-induced analgesic effects by promoting GABA synthesis and GABAergic transmission in spinal cord.
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Affiliation(s)
- Shiyun Jin
- Department of Anesthesiology, Second Affiliated Hospital of Anhui Medical University, Hefei, China; Laboratory for Integrative Neuroscience, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, MD, USA
| | - Resat Cinar
- Laboratory for Metabolic Diseases, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, MD, USA
| | - Xudong Hu
- Department of Anesthesiology, Second Affiliated Hospital of Anhui Medical University, Hefei, China
| | - Yuhong Lin
- Laboratory for Liver Diseases, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, MD, USA
| | - Guoxiang Luo
- Laboratory for Integrative Neuroscience, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, MD, USA
| | - David M Lovinger
- Laboratory for Integrative Neuroscience, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, MD, USA
| | - Ye Zhang
- Department of Anesthesiology, Second Affiliated Hospital of Anhui Medical University, Hefei, China.
| | - Li Zhang
- Laboratory for Integrative Neuroscience, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, MD, USA.
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18
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Kim KW, Suh BC. Ethanol inhibits Kv7.2/7.3 channel open probability by reducing the PI(4,5)P2 sensitivity of Kv7.2 subunit. BMB Rep 2021. [PMID: 33408002 PMCID: PMC8249878 DOI: 10.5483/bmbrep.2021.54.6.231] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022] Open
Abstract
Ethanol often causes critical health problems by altering the neuro-nal activities of the central and peripheral nerve systems. One of the cellular targets of ethanol is the plasma membrane proteins including ion channels and receptors. Recently, we reported that ethanol elevates membrane excitability in sympathetic neurons by inhibiting Kv7.2/7.3 channels in a cell type-specific manner. Even though our studies revealed that the inhibitory effects of ethanol on the Kv7.2/7.3 channel was diminished by the increase of plasma membrane phosphatidylinositol 4,5-bisphosphate (PI (4,5)P2), the molecular mechanism of ethanol on Kv7.2/7.3 channel inhibition remains unclear. By investigating the kinetics of Kv7.2/7.3 current in high K+ solution, we found that ethanol inhibited Kv7.2/7.3 channels through a mechanism distinct from that of tetraethylammonium (TEA) which enters into the pore and blocks the gate of the channels. Using a non-stationary noise analysis (NSNA), we demonstrated that the inhibitory effect of ethanol is the result of reduction of open probability (PO) of the Kv7.2/7.3 channel, but not of a single channel current (i) or channel number (N). Finally, ethanol selectively facilitated the kinetics of Kv7.2 current suppression by voltage-sensing phosphatase (VSP)-induced PI(4,5)P2 depletion, while it slowed down Kv7.2 current recovery from the VSP-induced inhibition. Together our results suggest that ethanol regulates neuronal activity through the reduction of open probability and PI(4,5)P2 sensitivity of Kv7.2/7.3 channels.
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Affiliation(s)
- Kwon-Woo Kim
- Department of Brain and Cognitive Sciences, Daegu Gyeongbuk Institute of Science and Technology (DGIST), Daegu 42988, Korea
| | - Byung-Chang Suh
- Department of Brain and Cognitive Sciences, Daegu Gyeongbuk Institute of Science and Technology (DGIST), Daegu 42988, Korea
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19
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Daack CW, Yeh D, Busch M, Kliethermes CL. GABAergic regulation of locomotion before and during an ethanol exposure in Drosophila melanogaster. Behav Brain Res 2021; 410:113369. [PMID: 34015397 DOI: 10.1016/j.bbr.2021.113369] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2021] [Revised: 04/30/2021] [Accepted: 05/14/2021] [Indexed: 11/17/2022]
Abstract
Ethanol at low doses induces a locomotor stimulant response across a range of phylogenetically diverse species. In rodents, this response is commonly used as an index of ethanol's disinhibitory, anxiolytic, or reinforcing effects, and its expression is regulated by signaling through a number of conserved neurotransmitter systems. In the current experiments, we asked whether ethanol-induced locomotor stimulation in the fruit fly Drosophila melanogaster might be mediated by ionotropic GABA receptors. We measured basal and ethanol-stimulated locomotion in flies expressing RNAi directed against three known subunits of ionotropic GABA receptors, and also examined the effects of picrotoxin feeding on these behaviors. We found that RNAi-mediated knockdown of a subunit of fly ionotropic GABA receptors, RDL, in all neurons resulted in an increased ethanol-induced locomotor stimulant response, while knockdown of two other subunits, LCCH3 and GRD, did not affect the responses. The effect of pan neuronal RDL knockdown was recapitulated with selective RDL knockdown in cholinergic neurons, and increased ethanol-induced locomotor stimulation was also seen by feeding the GABAA antagonist picrotoxin to flies prior to behavioral testing. However, the increase in ethanol-stimulated locomotion in each of these experiments was largely accounted for by decreased baseline activity. Our results indicate that ionotropic GABA receptors might be a conserved mediator of the locomotor stimulant effects of ethanol, but that alternative experimental approaches will be necessary to disentangle effects of GABAergic manipulations on baseline and ethanol-stimulated locomotion in flies.
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Affiliation(s)
- Calvin W Daack
- Drake University, 318 Olin Hall, 1344 27thStreet, Des Moines, IA, 50311, United States
| | - Derek Yeh
- Drake University, 318 Olin Hall, 1344 27thStreet, Des Moines, IA, 50311, United States
| | - Marc Busch
- Drake University, 318 Olin Hall, 1344 27thStreet, Des Moines, IA, 50311, United States
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20
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Pandey P, Singh A, Kaur H, Ghosh-Roy A, Babu K. Increased dopaminergic neurotransmission results in ethanol dependent sedative behaviors in Caenorhabditis elegans. PLoS Genet 2021; 17:e1009346. [PMID: 33524034 PMCID: PMC7877767 DOI: 10.1371/journal.pgen.1009346] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2020] [Revised: 02/11/2021] [Accepted: 01/06/2021] [Indexed: 12/19/2022] Open
Abstract
Ethanol is a widely used drug, excessive consumption of which could lead to medical conditions with diverse symptoms. Ethanol abuse causes dysfunction of memory, attention, speech and locomotion across species. Dopamine signaling plays an essential role in ethanol dependent behaviors in animals ranging from C. elegans to humans. We devised an ethanol dependent assay in which mutants in the dopamine autoreceptor, dop-2, displayed a unique sedative locomotory behavior causing the animals to move in circles while dragging the posterior half of their body. Here, we identify the posterior dopaminergic sensory neuron as being essential to modulate this behavior. We further demonstrate that in dop-2 mutants, ethanol exposure increases dopamine secretion and functions in a DVA interneuron dependent manner. DVA releases the neuropeptide NLP-12 that is known to function through cholinergic motor neurons and affect movement. Thus, DOP-2 modulates dopamine levels at the synapse and regulates alcohol induced movement through NLP-12.
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Affiliation(s)
- Pratima Pandey
- Department of Biological Sciences, Indian Institute of Science Education and Research (IISER) Mohali, Mohali, India
| | - Anuradha Singh
- Department of Biological Sciences, Indian Institute of Science Education and Research (IISER) Mohali, Mohali, India
| | - Harjot Kaur
- National Brain Research Centre, Gurgaon, India
| | | | - Kavita Babu
- Department of Biological Sciences, Indian Institute of Science Education and Research (IISER) Mohali, Mohali, India
- Centre for Neuroscience, Indian Institute of Science (IISc), Bangalore, India
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21
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Abstract
Alcohol dependence is a chronically relapsing disorder characterized by compulsive drug-seeking and drug-taking, loss of control in limiting intake, and the emergence of a withdrawal syndrome in the absence of the drug. Accumulating evidence suggests an important role for synaptic transmission in the central nucleus of the amygdala (CeA) in mediating alcohol-related behaviors and neuroadaptive mechanisms associated with alcohol dependence. Acute alcohol facilitates γ-aminobutyric acid (GABA)ergic transmission in the CeA via both pre- and postsynaptic mechanisms, and chronic alcohol increases baseline GABAergic transmission. Acute alcohol inhibits glutamatergic transmission via effects at N-methyl-d-aspartate (NMDA) and α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptors in the CeA, whereas chronic alcohol up-regulates NMDA receptor (NMDAR)-mediated transmission. Pro- (e.g., corticotropin-releasing factor [CRF]) and antistress (e.g., nociceptin/orphanin FQ, oxytocin) neuropeptides affect alcohol- and anxiety-related behaviors, and also alter the alcohol-induced effects on CeA neurotransmission. Alcohol dependence produces plasticity in these neuropeptide systems, reflecting a recruitment of those systems during the transition to alcohol dependence.
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Affiliation(s)
- Marisa Roberto
- Departments of Molecular Medicine and Neuroscience, The Scripps Research Institute, La Jolla, California 92037, USA
| | - Dean Kirson
- Departments of Molecular Medicine and Neuroscience, The Scripps Research Institute, La Jolla, California 92037, USA
| | - Sophia Khom
- Departments of Molecular Medicine and Neuroscience, The Scripps Research Institute, La Jolla, California 92037, USA
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22
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Shi M, Ren S, Chen H, Li J, Huang C, Li Y, Han Y, Li Y, Sun Z, Chen X, Xiong Z. Alcohol drinking inhibits NOTCH-PAX9 signaling in esophageal squamous epithelial cells. J Pathol 2021; 253:384-395. [PMID: 33314197 DOI: 10.1002/path.5602] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2020] [Revised: 11/22/2020] [Accepted: 12/08/2020] [Indexed: 01/04/2023]
Abstract
Alcohol drinking has been established as a major risk factor for esophageal diseases. Our previous study showed that ethanol exposure inhibited PAX9 expression in human esophageal squamous epithelial cells in vitro and in vivo. In this study, we aimed to investigate the molecular pathways through which alcohol drinking suppresses PAX9 in esophageal squamous epithelial cells. We first demonstrated the inhibition of NOTCH by ethanol exposure in vitro. NOTCH regulated PAX9 expression in KYSE510 and KYSE410 cells in vitro and in vivo. RBPJ and NOTCH intracellular domain (NIC) D1 ChIP-PCR confirmed Pax9 as a direct downstream target of NOTCH signaling in mouse esophagus. NOTCH inhibition by alcohol drinking was further validated in mouse esophagus and human tissue samples. In conclusion, ethanol exposure inhibited NOTCH signaling and thus suppressed PAX9 expression in esophageal squamous epithelial cells in vitro and in vivo. Our data support a novel mechanism of alcohol-induced esophageal injury through the inhibition of NOTCH-PAX9 signaling. © 2020 The Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
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Affiliation(s)
- Menghan Shi
- Beijing Stomatological Hospital, Capital Medical University, Beijing, PR China.,Cancer Research Program, Julius L Chambers Biomedical Biotechnology Research Institute, North Carolina Central University, Durham, NC, USA
| | - Shuang Ren
- Beijing Stomatological Hospital, Capital Medical University, Beijing, PR China.,Cancer Research Program, Julius L Chambers Biomedical Biotechnology Research Institute, North Carolina Central University, Durham, NC, USA
| | - Hao Chen
- Cancer Research Program, Julius L Chambers Biomedical Biotechnology Research Institute, North Carolina Central University, Durham, NC, USA
| | - Jing Li
- Cancer Research Program, Julius L Chambers Biomedical Biotechnology Research Institute, North Carolina Central University, Durham, NC, USA.,Department of Thoracic Surgery, Ningxia Medical University General Hospital, Yinchuan, PR China
| | - Caizhi Huang
- Cancer Research Program, Julius L Chambers Biomedical Biotechnology Research Institute, North Carolina Central University, Durham, NC, USA
| | - Yahui Li
- Cancer Research Program, Julius L Chambers Biomedical Biotechnology Research Institute, North Carolina Central University, Durham, NC, USA
| | - Yuning Han
- Department of Thoracic Surgery, Ningxia Medical University General Hospital, Yinchuan, PR China
| | - Yong Li
- Department of Thoracic Surgery, National Cancer Center, Cancer Hospital of Chinese Academy of Medical Sciences, Beijing, PR China
| | - Zheng Sun
- Beijing Stomatological Hospital, Capital Medical University, Beijing, PR China
| | - Xiaoxin Chen
- Cancer Research Program, Julius L Chambers Biomedical Biotechnology Research Institute, North Carolina Central University, Durham, NC, USA.,Center for Gastrointestinal Biology and Disease, Division of Gastroenterology and Hepatology, Department of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Zhaohui Xiong
- Cancer Research Program, Julius L Chambers Biomedical Biotechnology Research Institute, North Carolina Central University, Durham, NC, USA
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Zhao Y, Gameiro-Ros I, Glaaser IW, Slesinger PA. Advances in Targeting GIRK Channels in Disease. Trends Pharmacol Sci 2021; 42:203-215. [PMID: 33468322 DOI: 10.1016/j.tips.2020.12.002] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2020] [Revised: 11/30/2020] [Accepted: 12/11/2020] [Indexed: 12/12/2022]
Abstract
G protein-gated inwardly rectifying potassium (GIRK) channels are essential regulators of cell excitability in the brain. While they are implicated in a variety of neurological diseases in both human and animal model studies, their therapeutic potential has been largely untapped. Here, we review recent advances in the development of small molecule compounds that specifically modulate GIRK channels and compare them with first-generation compounds that exhibit off-target activity. We describe the method of discovery of these small molecule modulators, their chemical features, and their effects in vivo. These studies provide a promising outlook on the future development of subunit-specific GIRK modulators to regulate neuronal excitability in a brain region-specific manner.
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Affiliation(s)
- Yulin Zhao
- Nash Family Department of Neuroscience, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Isabel Gameiro-Ros
- Nash Family Department of Neuroscience, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Ian W Glaaser
- Nash Family Department of Neuroscience, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Paul A Slesinger
- Nash Family Department of Neuroscience, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA.
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24
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Shaidullov I, Ermakova E, Gaifullina A, Mosshammer A, Yakovlev A, Weiger TM, Hermann A, Sitdikova G. Alcohol metabolite acetic acid activates BK channels in a pH-dependent manner and decreases calcium oscillations and exocytosis of secretory granules in rat pituitary GH3 cells. Pflugers Arch 2021; 473:67-77. [PMID: 33113008 DOI: 10.1007/s00424-020-02484-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2020] [Revised: 10/16/2020] [Accepted: 10/20/2020] [Indexed: 12/11/2022]
Abstract
Acetaldehyde and acetic acid/acetate, the active metabolites of alcohol (ethanol, EtOH), generate actions of their own ranging from behavioral, physiological, to pathological/cancerogenic effects. EtOH and acetaldehyde have been studied to some depth, whereas the effects of acetic acid have been less well explored. In this study, we investigated the effect of acetic acid on big conductance calcium-activated potassium (BK) channels present in GH3 rat pituitary tumor cells in more detail. In whole cell voltage clamp recordings, extracellular application of acetic acid increased total outward currents in a dose-dependent manner. This effect was prevented after the application of the specific BK channel blocker paxilline. Acetic acid action was pH-dependent-in whole cell current and single BK channel recordings, open probability (Po) was significantly increased by extracellular pH reduction and decreased by neutral or base pH. Acetic acid hyperpolarized the membrane potential, whereas acidic physiological solution had a depolarizing effect. Moreover, acetic acid reduced calcium (Ca2+) oscillations and exocytosis of growth hormone contained secretory granules from GH3 cells. These effects were partially prevented by BK inhibitors-tetraethylammonium or paxillin. In conclusion, our experiments indicate that acetic acid activates BK channels in GH3 cells which eventually contribute to acetic acid-induced membrane hyperpolarization, cessation of Ca2+ oscillations, and decrease of growth hormone release.
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Affiliation(s)
- Ilnar Shaidullov
- Department of Human and Animal Physiology, Institute of Fundamental Medicine and Biology, Kazan Federal University, Kremlevskaya str. 18, Kazan, 420008, Russia
| | - Elizaveta Ermakova
- Department of Human and Animal Physiology, Institute of Fundamental Medicine and Biology, Kazan Federal University, Kremlevskaya str. 18, Kazan, 420008, Russia
| | | | - Anna Mosshammer
- Department of Neurophysiology and Neuropharmacology, Center of Physiology and Pharmacology, Medical University of Vienna, Vienna, Austria
| | - Aleksey Yakovlev
- Department of Human and Animal Physiology, Institute of Fundamental Medicine and Biology, Kazan Federal University, Kremlevskaya str. 18, Kazan, 420008, Russia
| | - Thomas M Weiger
- Department of Biosciences, University of Salzburg, Salzburg, Austria
| | - Anton Hermann
- Department of Biosciences, University of Salzburg, Salzburg, Austria
| | - Guzel Sitdikova
- Department of Human and Animal Physiology, Institute of Fundamental Medicine and Biology, Kazan Federal University, Kremlevskaya str. 18, Kazan, 420008, Russia.
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25
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Alcohol. Alcohol 2021. [DOI: 10.1016/b978-0-12-816793-9.00001-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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26
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Ye L, Orynbayev M, Zhu X, Lim EY, Dereddi RR, Agarwal A, Bergles DE, Bhat MA, Paukert M. Ethanol abolishes vigilance-dependent astroglia network activation in mice by inhibiting norepinephrine release. Nat Commun 2020; 11:6157. [PMID: 33268792 PMCID: PMC7710743 DOI: 10.1038/s41467-020-19475-5] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2020] [Accepted: 10/16/2020] [Indexed: 12/17/2022] Open
Abstract
Norepinephrine adjusts sensory processing in cortical networks and gates plasticity enabling adaptive behavior. The actions of norepinephrine are profoundly altered by recreational drugs like ethanol, but the consequences of these changes on distinct targets such as astrocytes, which exhibit norepinephrine-dependent Ca2+ elevations during vigilance, are not well understood. Using in vivo two-photon imaging, we show that locomotion-induced Ca2+ elevations in mouse astroglia are profoundly inhibited by ethanol, an effect that can be reversed by enhancing norepinephrine release. Vigilance-dependent astroglial activation is abolished by deletion of α1A-adrenergic receptor from astroglia, indicating that norepinephrine acts directly on these ubiquitous glial cells. Ethanol reduces vigilance-dependent Ca2+ transients in noradrenergic terminals, but has little effect on astroglial responsiveness to norepinephrine, suggesting that ethanol suppresses their activation by inhibiting norepinephrine release. Since abolition of astroglia Ca2+ activation does not affect motor coordination, global suppression of astroglial networks may contribute to the cognitive effects of alcohol intoxication. The effects of norepinephrine on sensory processing in cortical networks are altered by recreational drugs like ethanol. The authors show that ethanol suppresses the activation of astrocytes by inhibiting norepinephrine release which may contribute to the cognitive effects of alcohol intoxication.
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Affiliation(s)
- Liang Ye
- Department of Cellular and Integrative Physiology, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA
| | - Murat Orynbayev
- Department of Cellular and Integrative Physiology, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA
| | - Xiangyu Zhu
- Department of Cellular and Integrative Physiology, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA.,Xiangya School of Medicine, Central South University, Changsha, Hunan, China
| | - Eunice Y Lim
- Department of Cellular and Integrative Physiology, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA.,Center for Biomedical Neuroscience, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA
| | - Ram R Dereddi
- The Chica and Heinz Schaller Research Group, Institute for Anatomy and Cell Biology, Heidelberg University, Heidelberg, Germany
| | - Amit Agarwal
- The Chica and Heinz Schaller Research Group, Institute for Anatomy and Cell Biology, Heidelberg University, Heidelberg, Germany.,Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Dwight E Bergles
- Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD, USA.,Johns Hopkins Kavli Neuroscience Discovery Institute, Baltimore, MD, USA
| | - Manzoor A Bhat
- Department of Cellular and Integrative Physiology, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA.,Center for Biomedical Neuroscience, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA
| | - Martin Paukert
- Department of Cellular and Integrative Physiology, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA. .,Center for Biomedical Neuroscience, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA.
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27
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Abstract
Ethanol is a chemoattractant for Bacillus subtilis even though it is not metabolized and inhibits growth. B. subtilis likely uses ethanol to find ethanol-fermenting microorganisms to utilize as prey. Two chemoreceptors sense ethanol: HemAT and McpB. HemAT’s myoglobin-like sensing domain directly binds ethanol, but the heme group is not involved. McpB is a transmembrane receptor consisting of an extracellular sensing domain and a cytoplasmic signaling domain. While most attractants bind the extracellular sensing domain, we found that ethanol directly binds between intermonomer helices of the cytoplasmic signaling domain of McpB, using a mechanism akin to those identified in many mammalian ethanol-binding proteins. Our results indicate that the sensory repertoire of chemoreceptors extends beyond the sensing domain and can directly involve the signaling domain. Motile bacteria sense chemical gradients using chemoreceptors, which consist of distinct sensing and signaling domains. The general model is that the sensing domain binds the chemical and the signaling domain induces the tactic response. Here, we investigated the unconventional sensing mechanism for ethanol taxis in Bacillus subtilis. Ethanol and other short-chain alcohols are attractants for B. subtilis. Two chemoreceptors, McpB and HemAT, sense these alcohols. In the case of McpB, the signaling domain directly binds ethanol. We were further able to identify a single amino acid residue, Ala431, on the cytoplasmic signaling domain of McpB that, when mutated to serine, reduces taxis to alcohols. Molecular dynamics simulations suggest that the conversion of Ala431 to serine increases coiled-coil packing within the signaling domain, thereby reducing the ability of ethanol to bind between the helices of the signaling domain. In the case of HemAT, the myoglobin-like sensing domain binds ethanol, likely between the helices encapsulating the heme group. Aside from being sensed by an unconventional mechanism, ethanol also differs from many other chemoattractants because it is not metabolized by B. subtilis and is toxic. We propose that B. subtilis uses ethanol and other short-chain alcohols to locate prey, namely, alcohol-producing microorganisms.
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28
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Dulman RS, Wandling GM, Pandey SC. Epigenetic mechanisms underlying pathobiology of alcohol use disorder. CURRENT PATHOBIOLOGY REPORTS 2020; 8:61-73. [PMID: 33747641 DOI: 10.1007/s40139-020-00210-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Purpose of review Chronic alcohol use is a worldwide problem with multifaceted consequences including multiplying medical costs and sequelae, societal effects like drunk driving and assault, and lost economic productivity. These large-scale outcomes are driven by the consumption of ethanol, a small permeable molecule that has myriad effects in the human body, particularly in the liver and brain. In this review, we have summarized effects of acute and chronic alcohol consumption on epigenetic mechanisms that may drive pathobiology of Alcohol Use Disorder (AUD) while identifying areas of need for future research. Recent findings Epigenetics has emerged as an interesting field of biology at the intersection of genetics and the environment, and ethanol in particular has been identified as a potent modulator of the epigenome with various effects on DNA methylation, histone modifications, and non-coding RNAs. These changes alter chromatin dynamics and regulate gene expression that contribute to behavioral and physiological changes leading to the development of AUD psychopathology and cancer pathology. Summary Evidence and discussion presented here from preclinical results and available translational studies have increased our knowledge of the epigenetic effects of alcohol consumption. These studies have identified targets that can be used to develop better therapies to reduce chronic alcohol abuse and mitigate its societal burden and pathophysiology.
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Affiliation(s)
- Russell S Dulman
- Center for Alcohol Research in Epigenetics, Department of Psychiatry, University of Illinois at Chicago, Chicago, IL 60612, USA
| | - Gabriela M Wandling
- Center for Alcohol Research in Epigenetics, Department of Psychiatry, University of Illinois at Chicago, Chicago, IL 60612, USA
| | - Subhash C Pandey
- Center for Alcohol Research in Epigenetics, Department of Psychiatry, University of Illinois at Chicago, Chicago, IL 60612, USA.,Jesse Brown VA Medical Center, Chicago, IL 60612, USA
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29
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You Y, Das J. Effect of ethanol on Munc13-1 C1 in Membrane: A Molecular Dynamics Simulation Study. Alcohol Clin Exp Res 2020; 44:1344-1355. [PMID: 32424866 DOI: 10.1111/acer.14363] [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: 09/07/2019] [Accepted: 05/06/2020] [Indexed: 12/26/2022]
Abstract
BACKGROUND EtOH has a significant effect on synaptic plasticity. Munc13-1 is an essential presynaptic active zone protein involved in priming the synaptic vesicle and releasing neurotransmitter in the brain. It is a peripheral membrane protein and binds to the activator, diacylglycerol (DAG)/phorbol ester at its membrane-targeting C1 domain. Our previous studies identified Glu-582 of C1 domain as the alcohol-binding residue (Das, J. et al, J. Neurochem., 126, 715-726, 2013). METHODS Here, we describe a 250 ns molecular dynamics (MD) simulation study on the interaction of EtOH and the activator-bound Munc13-1 C1 in the presence of varying concentrations of phosphatidylserine (PS). RESULTS In this study, Munc13-1 C1 shows higher conformational stability in EtOH than in water. It forms fewer hydrogen bonds with phorbol 13-acetate in the presence of EtOH than in water. EtOH also affected the interaction between the protein and the membrane and between the activator and the membrane. Similar studies in a E582A mutant suggest that these effects of EtOH are mostly mediated through Glu-582. CONCLUSIONS EtOH forms hydrogen bonds with Glu-582. While occupancy of the EtOH molecules at the vicinity (4Å) of Glu-582 is 34.4%, the occupancy in the E582A mutant is 26.5% of the simulation time. In addition, the amount of PS in the membrane influences the conformational stability of the C1 domain and interactions in the ternary complex. This study is important in providing the structural basis of EtOH's effects on synaptic plasticity.
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Affiliation(s)
- Youngki You
- From the Department of Pharmacological and Pharmaceutical Sciences, College of Pharmacy, University of Houston, Houston, Texas
| | - Joydip Das
- From the Department of Pharmacological and Pharmaceutical Sciences, College of Pharmacy, University of Houston, Houston, Texas
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30
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Müller CP. Drug instrumentalization. Behav Brain Res 2020; 390:112672. [PMID: 32442549 DOI: 10.1016/j.bbr.2020.112672] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2020] [Revised: 04/20/2020] [Accepted: 04/21/2020] [Indexed: 12/19/2022]
Abstract
Psychoactive drugs with addiction potential are widely used by people of virtually all cultures in a non-addictive way. In order to understand this behaviour, its population penetrance, and its persistence, drug instrumentalization was suggested as a driving force for this consumption. Drug instrumentalization theory holds that psychoactive drugs are consumed in a very systematic way in order to make other, non-drug-related behaviours more efficient. Here, we review the evolutionary origin of this behaviour and its psychological mechanisms and explore the neurobiological and neuropharmacological mechanisms underlying them. Instrumentalization goals are discussed, for which an environmentally selective and mental state-dependent consumption of psychoactive drugs can be learned and maintained in a non-addictive way. A small percentage of people who regularly instrumentalize psychoactive drugs make a transition to addiction, which often starts with qualitative and quantitative changes in the instrumentalization goals. As such, addiction is proposed to develop from previously established long-term drug instrumentalization. Thus, preventing and treating drug addiction in an individualized medicine approach may essentially require understanding and supporting personal instrumentalization goals.
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Affiliation(s)
- Christian P Müller
- Department of Psychiatry and Psychotherapy, University Hospital, Friedrich-Alexander-University Erlangen-Nürnberg, Schwabachanlage 6, 91054 Erlangen, Germany.
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31
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Ahmed SH, Badiani A, Miczek KA, Müller CP. Non-pharmacological factors that determine drug use and addiction. Neurosci Biobehav Rev 2020; 110:3-27. [PMID: 30179633 PMCID: PMC6395570 DOI: 10.1016/j.neubiorev.2018.08.015] [Citation(s) in RCA: 46] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2018] [Revised: 07/26/2018] [Accepted: 08/28/2018] [Indexed: 12/26/2022]
Abstract
Based on their pharmacological properties, psychoactive drugs are supposed to take control of the natural reward system to finally drive compulsory drug seeking and consumption. However, psychoactive drugs are not used in an arbitrary way as pure pharmacological reinforcement would suggest, but rather in a highly specific manner depending on non-pharmacological factors. While pharmacological effects of psychoactive drugs are well studied, neurobiological mechanisms of non-pharmacological factors are less well understood. Here we review the emerging neurobiological mechanisms beyond pharmacological reinforcement which determine drug effects and use frequency. Important progress was made on the understanding of how the character of an environment and social stress determine drug self-administration. This is expanded by new evidence on how behavioral alternatives and opportunities for drug instrumentalization generate different patterns of drug choice. Emerging evidence suggests that the neurobiology of non-pharmacological factors strongly determines pharmacological and behavioral drug action and may, thus, give rise for an expanded system's approach of psychoactive drug use and addiction.
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Affiliation(s)
- Serge H Ahmed
- Université de Bordeaux, Institut des Maladies Neurodégénératives, UMR 5293, 146 rue Léo-Saignat, F-33000 Bordeaux, France; CNRS, Institut des Maladies Neurodégénératives, UMR 5293, 146 rue Léo-Saignat, F-33000 Bordeaux, France
| | - Aldo Badiani
- Department of Physiology and Pharmacology, Sapienza University of Rome, Piazzale Aldo Moro 5, 00185 Rome, Italy; Sussex Addiction Research and Intervention Centre (SARIC), School of Psychology, University of Sussex, BN1 9RH Brighton, UK
| | - Klaus A Miczek
- Psychology Department, Tufts University, Bacon Hall, 530 Boston Avenue, Medford, MA 02155, USA; Department of Neuroscience, Sackler School of Graduate Biomedical Sciences, Boston, MA 02111, USA
| | - Christian P Müller
- Department of Psychiatry and Psychotherapy, University Clinic, Friedrich-Alexander-University Erlangen-Nuremberg, Schwabachanlage 6, 91054 Erlangen, Germany.
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32
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Lovely CB. Quantification of Ethanol Levels in Zebrafish Embryos Using Head Space Gas Chromatography. J Vis Exp 2020. [PMID: 32116298 DOI: 10.3791/60766] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022] Open
Abstract
Fetal Alcohol Spectrum Disorders (FASD) describe a highly variable continuum of ethanol-induced developmental defects, including facial dysmorphologies and neurological impairments. With a complex pathology, FASD affects approximately 1 in 100 children born in the United States each year. Due to the highly variable nature of FASD, animal models have proven critical in our current mechanistic understanding of ethanol-induced development defects. An increasing number of laboratories has focused on using zebrafish to examine ethanol-induced developmental defects. Zebrafish produce large numbers of externally fertilized, genetically tractable, translucent embryos. This allows researchers to precisely control timing and dosage of ethanol exposure in multiple genetic contexts and quantify the impact of embryonic ethanol exposure through live imaging techniques. This, combined with the high degree of conservation of both genetics and development with humans, has proven zebrafish to be a powerful model in which to study the mechanistic basis of ethanol teratogenicity. However, ethanol exposure regimens have varied between different zebrafish studies, which has confounded the interpretation of zebrafish data across these studies. Here is a protocol to quantify ethanol concentrations in zebrafish embryos using head space gas chromatography.
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Affiliation(s)
- C Ben Lovely
- Department of Biochemistry and Molecular Genetics, Alcohol Research Center, University of Louisville;
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33
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Washburn S, Fremont R, Moreno-Escobar MC, Angueyra C, Khodakhah K. Acute cerebellar knockdown of Sgce reproduces salient features of myoclonus-dystonia (DYT11) in mice. eLife 2019; 8:52101. [PMID: 31868164 PMCID: PMC6959989 DOI: 10.7554/elife.52101] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2019] [Accepted: 12/20/2019] [Indexed: 12/15/2022] Open
Abstract
Myoclonus dystonia (DYT11) is a movement disorder caused by loss-of-function mutations in SGCE and characterized by involuntary jerking and dystonia that frequently improve after drinking alcohol. Existing transgenic mouse models of DYT11 exhibit only mild motor symptoms, possibly due to rodent-specific developmental compensation mechanisms, which have limited the study of neural mechanisms underlying DYT11. To circumvent potential compensation, we used short hairpin RNA (shRNA) to acutely knock down Sgce in the adult mouse and found that this approach produced dystonia and repetitive, myoclonic-like, jerking movements in mice that improved after administration of ethanol. Acute knockdown of Sgce in the cerebellum, but not the basal ganglia, produced motor symptoms, likely due to aberrant cerebellar activity. The acute knockdown model described here reproduces the salient features of DYT11 and provides a platform to study the mechanisms underlying symptoms of the disorder, and to explore potential therapeutic options.
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Affiliation(s)
- Samantha Washburn
- Dominick P. Purpura Department of Neuroscience, Albert Einstein College of Medicine, New York, United States
| | - Rachel Fremont
- Dominick P. Purpura Department of Neuroscience, Albert Einstein College of Medicine, New York, United States
| | - Maria Camila Moreno-Escobar
- Dominick P. Purpura Department of Neuroscience, Albert Einstein College of Medicine, New York, United States
| | - Chantal Angueyra
- Dominick P. Purpura Department of Neuroscience, Albert Einstein College of Medicine, New York, United States
| | - Kamran Khodakhah
- Dominick P. Purpura Department of Neuroscience, Albert Einstein College of Medicine, New York, United States
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34
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Das J. SNARE Complex-Associated Proteins and Alcohol. Alcohol Clin Exp Res 2019; 44:7-18. [PMID: 31724225 DOI: 10.1111/acer.14238] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2019] [Accepted: 11/07/2019] [Indexed: 12/23/2022]
Abstract
Alcohol addiction causes major health problems throughout the world, causing numerous deaths and incurring a huge economic burden to society. To develop an intervention for alcohol addiction, it is necessary to identify molecular target(s) of alcohol and associated molecular mechanisms of alcohol action. The functions of many central and peripheral synapses are impacted by low concentrations of ethanol (EtOH). While the postsynaptic targets and mechanisms are studied extensively, there are limited studies on the presynaptic targets and mechanisms. This article is an endeavor in this direction, focusing on the effect of EtOH on the presynaptic proteins associated with the neurotransmitter release machinery. Studies on the effects of EtOH at the levels of gene, protein, and behavior are highlighted in this article.
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Affiliation(s)
- Joydip Das
- Department of Pharmacological and Pharmaceutical Sciences, College of Pharmacy, University of Houston, Houston, Texas
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35
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Kim KW, Kim K, Lee H, Suh BC. Ethanol Elevates Excitability of Superior Cervical Ganglion Neurons by Inhibiting Kv7 Channels in a Cell Type-Specific and PI(4,5)P 2-Dependent Manner. Int J Mol Sci 2019; 20:E4419. [PMID: 31500374 PMCID: PMC6770022 DOI: 10.3390/ijms20184419] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2019] [Revised: 09/04/2019] [Accepted: 09/05/2019] [Indexed: 12/13/2022] Open
Abstract
Alcohol causes diverse acute and chronic symptoms that often lead to critical health problems. Exposure to ethanol alters the activities of sympathetic neurons that control the muscles, eyes, and blood vessels in the brain. Although recent studies have revealed the cellular targets of ethanol, such as ion channels, the molecular mechanism by which alcohol modulates the excitability of sympathetic neurons has not been determined. Here, we demonstrated that ethanol increased the discharge of membrane potentials in sympathetic neurons by inhibiting the M-type or Kv7 channel consisting of the Kv7.2/7.3 subunits, which were involved in determining the membrane potential and excitability of neurons. Three types of sympathetic neurons, classified by their threshold of activation and firing patterns, displayed distinct sensitivities to ethanol, which were negatively correlated with the size of the Kv7 current that differs depending on the type of neuron. Using a heterologous expression system, we further revealed that the inhibitory effects of ethanol on Kv7.2/7.3 currents were facilitated or diminished by adjusting the amount of plasma membrane phosphatidylinositol 4,5-bisphosphate (PI(4,5)P2). These results suggested that ethanol and PI(4,5)P2 modulated gating of the Kv7 channel in superior cervical ganglion neurons in an antagonistic manner, leading to regulation of the membrane potential and neuronal excitability, as well as the physiological functions mediated by sympathetic neurons.
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Affiliation(s)
- Kwon-Woo Kim
- Department of Brain and cognitive sciences, Daegu Gyeongbuk Institute of Science and Technology (DGIST), Daegu 42988, Korea.
| | - Keetae Kim
- Department of New biology, Daegu Gyeongbuk Institute of Science and Technology (DGIST), Daegu 42988, Korea.
| | - Hyosang Lee
- Department of Brain and cognitive sciences, Daegu Gyeongbuk Institute of Science and Technology (DGIST), Daegu 42988, Korea.
| | - Byung-Chang Suh
- Department of Brain and cognitive sciences, Daegu Gyeongbuk Institute of Science and Technology (DGIST), Daegu 42988, Korea.
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36
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Morel C, Montgomery S, Han MH. Nicotine and alcohol: the role of midbrain dopaminergic neurons in drug reinforcement. Eur J Neurosci 2019; 50:2180-2200. [PMID: 30251377 PMCID: PMC6431587 DOI: 10.1111/ejn.14160] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2018] [Revised: 07/31/2018] [Accepted: 08/20/2018] [Indexed: 12/11/2022]
Abstract
Nicotine and alcohol addiction are leading causes of preventable death worldwide and continue to constitute a huge socio-economic burden. Both nicotine and alcohol perturb the brain's mesocorticolimbic system. Dopamine (DA) neurons projecting from the ventral tegmental area (VTA) to multiple downstream structures, including the nucleus accumbens, prefrontal cortex, and amygdala, are highly involved in the maintenance of healthy brain function. VTA DA neurons play a crucial role in associative learning and reinforcement. Nicotine and alcohol usurp these functions, promoting reinforcement of drug taking behaviors. In this review, we will first describe how nicotine and alcohol individually affect VTA DA neurons by examining how drug exposure alters the heterogeneous VTA microcircuit and network-wide projections. We will also examine how coadministration or previous exposure to nicotine or alcohol may augment the reinforcing effects of the other. Additionally, this review briefly summarizes the role of VTA DA neurons in nicotine, alcohol, and their synergistic effects in reinforcement and also addresses the remaining questions related to the circuit-function specificity of the dopaminergic system in mediating nicotine/alcohol reinforcement and comorbidity.
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Affiliation(s)
- Carole Morel
- Department of Pharmacological Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Department of Neuroscience, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Center for Affective Neuroscience, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Sarah Montgomery
- Department of Pharmacological Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Department of Neuroscience, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Center for Affective Neuroscience, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Ming-Hu Han
- Department of Pharmacological Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Department of Neuroscience, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Center for Affective Neuroscience, Icahn School of Medicine at Mount Sinai, New York, NY, USA
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37
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Abstract
Ethanol produces intoxication through actions on numerous molecular and cellular targets. Adaptations involving these and other targets contribute to chronic drug actions that underlie continued and problematic drinking. Among the mechanisms involved in these ethanol actions are alterations in presynaptic mechanisms of synaptic transmission, including presynaptic protein function and excitation-secretion coupling. At synapses in the central nervous system (CNS), excitation-secretion coupling involves ion channel activation followed by vesicle fusion and neurotransmitter release. These mechanisms are altered by presynaptic neurotransmitter receptors and prominently by G protein-coupled receptors (GPCRs). Studies over the last 20-25 years have revealed that acute ethanol exposure alters neurotransmitter secretion, with especially robust effects on synapses that use the neurotransmitter gamma-aminobutyric acid (GABA). Intracellular signaling pathways involving second messengers such as cyclic AMP and calcium are implicated in these acute ethanol actions. Ethanol-induced release of neuropeptides and small molecule neurotransmitters that act on presynaptic GPCRs also contribute to presynaptic potentiation at synapses in the amygdala and hippocampus and inhibition of GABA release in the striatum. Prolonged exposure to ethanol alters neurotransmitter release at many CNS GABAergic and glutamatergic synapses, and changes in GPCR function are implicated in many of these neuroadaptations. These presynaptic neuroadaptations appear to involve compensation for acute drug effects at some synapses, but "allostatic" effects that result in long-term resetting of synaptic efficacy occur at others. Current investigations are determining how presynaptic neuroadaptations contribute to behavioral changes at different stages of alcohol drinking, with increasing focus on circuit adaptations underlying these behaviors. This chapter will discuss the acute and chronic presynaptic effects of ethanol in the CNS, as well as some of the consequences of these effects in amygdala and corticostriatal circuits that are related to excessive seeking/drinking and ethanol abuse.
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Affiliation(s)
- David M Lovinger
- Laboratory for Integrative Neuroscience, Division of Intramural Clinical and Biological Research, National Institute on Alcohol Abuse and Alcoholism, Bethesda, MD, USA.
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Tobin SJ, Wakefield DL, Terenius L, Vukojević V, Jovanović-Talisman T. Ethanol and Naltrexone Have Distinct Effects on the Lateral Nano-organization of Mu and Kappa Opioid Receptors in the Plasma Membrane. ACS Chem Neurosci 2019; 10:667-676. [PMID: 30418735 DOI: 10.1021/acschemneuro.8b00488] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
The complex spatiotemporal organization of proteins and lipids in the plasma membrane is an important determinant of receptor function. Certain substances, such as ethanol, can penetrate into the hydrophobic regions of the plasma membrane. By altering protein-lipid and protein-protein interactions, these substances can modify the dynamic lateral organization and the function of plasma membrane receptors. To assess changes in plasma membrane receptor organization, we used photoactivated localization microscopy (PALM). This single molecule localization microscopy technique was employed to quantitatively characterize the effects of pharmacologically relevant concentrations of ethanol and naltrexone (an opioid receptor antagonist and medication used to treat alcohol use disorders) on the lateral nano-organization of mu and kappa opioid receptors (MOR and KOR, respectively). Ethanol affected the lateral organization of MOR and KOR similarly: It reduced the size and occupancy of opioid receptor nanodomains and increased the fraction of opioid receptors residing outside of nanodomains. In contrast, naltrexone affected MOR and KOR lateral organization differently. It significantly increased KOR surface density, nanodomain size, and the occupancy of KOR nanodomains. However, naltrexone marginally affected these parameters for MOR. Pretreatment with naltrexone largely protected against ethanol-induced changes in MOR and KOR lateral organization. Based on these data, we propose a putative mechanism of naltrexone action that operates in addition to its canonical antagonistic effect on MOR- and KOR-mediated signaling.
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Affiliation(s)
- Steven J. Tobin
- Department of Molecular Medicine, Beckman Research Institute, City of Hope Comprehensive Cancer Center, Duarte, California 91010, United States
| | - Devin L. Wakefield
- Department of Molecular Medicine, Beckman Research Institute, City of Hope Comprehensive Cancer Center, Duarte, California 91010, United States
| | - Lars Terenius
- Center for Molecular Medicine, Department of Clinical Neuroscience, Karolinska Institutet, Stockholm 17176, Sweden
| | - Vladana Vukojević
- Center for Molecular Medicine, Department of Clinical Neuroscience, Karolinska Institutet, Stockholm 17176, Sweden
| | - Tijana Jovanović-Talisman
- Department of Molecular Medicine, Beckman Research Institute, City of Hope Comprehensive Cancer Center, Duarte, California 91010, United States
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Das J. Identification of alcohol-binding site(s) in proteins using diazirine-based photoaffinity labeling and mass spectrometry. Chem Biol Drug Des 2018; 93:1158-1165. [PMID: 30346111 DOI: 10.1111/cbdd.13403] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2018] [Revised: 09/03/2018] [Accepted: 09/15/2018] [Indexed: 01/12/2023]
Abstract
Defining molecular targets of alcohol and understanding the molecular mechanism of alcohol actions are necessary to develop effective therapeutics for alcohol use disorder (AUD). Here, we describe a detailed protocol for identifying alcohol-binding site(s) in proteins using diazirine-based azialcohol as photoaffinity labeling agents. Upon photoirradiation, azialcohol photoincorporates into alcohol-binding proteins. The stoichiometry and site of azialcohol photoincorporation can be determined using high-resolution mass spectrometry. Identification of the alcohol-binding residues in protein followed by measuring the biological significance of these residues in regulating alcohol action are important steps in characterizing the molecular targets of alcohol.
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Affiliation(s)
- Joydip Das
- Department of Pharmacological and Pharmaceutical Sciences, College of Pharmacy, University of Houston, Houston, Texas
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Tochitani S. Functions of Maternally-Derived Taurine in Fetal and Neonatal Brain Development. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2018; 975 Pt 1:17-25. [PMID: 28849440 DOI: 10.1007/978-94-024-1079-2_2] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Taurine (2-aminoethanesulfonic acid) is a sulfur-containing organic acid, which has various physiological functions, including membrane stabilization, cell-volume regulation, mitochondrial protein translocation, anti-oxidative activity, neuroprotection against neurotoxicity and modulation of intracellular calcium levels. Taurine also activates GABAA receptors and glycine receptors. Mammalian fetuses and infants are dependent on taurine delivered from their mothers via either the placenta or their mother's milk. Taurine is a molecule that links mother-fetus or mother-infant bonding.This review describes the functions of taurine and the mechanisms of action of taurine in fetal and brain development. Taurine is involved in regulating the proliferation of neural progenitors, migration of newly-generated neurons, and the synapse formation of neurons after migration during fetal and neonatal development. In this review, we also discuss the environmental factors that might influence the functional roles of taurine in neural development.
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Affiliation(s)
- Shiro Tochitani
- Division of Development of Mental Functions, Research Center for Child Mental Development, University of Fukui, Fukui, 910-1193, Japan.
- Division of Developmental Higher Brain Functions, United Graduate School of Child Development, Osaka University, Kanazawa University, Hamamatsu University School of Medicine, Chiba University and University of Fukui, Osaka, 565-0871, Japan.
- Department of Radiological Technology, Faculty of Health Science, Suzuka University of Medical Science, Mie, 513-8670, Japan.
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Ethanol's Effects on Transient Receptor Potential Channel Expression in Brain Microvascular Endothelial Cells. J Neuroimmune Pharmacol 2018; 13:498-508. [PMID: 29987591 DOI: 10.1007/s11481-018-9796-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2018] [Accepted: 06/28/2018] [Indexed: 12/14/2022]
Abstract
Ethanol (EtOH), the main ingredient in alcoholic beverages, is well known for its behavioral, physiological, and immunosuppressive effects. There is evidence that EtOH acts through protein targets to exert its physiological effects; however, the mechanisms underlying EtOH's effects on inflammatory processes, particularly at the blood-brain barrier (BBB), are still poorly understood. Transient receptor potential (TRP) channels, the vanguards of human sensory systems, are novel molecular receptors significantly affected by EtOH, and are heavily expressed in brain microvascular endothelial cells (BMVECs), one of the cellular constituents of the BBB. EtOH's actions on endothelial TRP channels could affect intracellular Ca2+ and Mg2+ dynamics, which mediate leukocyte adhesion to endothelial cells and endothelial permeability at the BBB, thus altering immune and inflammatory responses. We examined the basal expression profiles of all 29 known mammalian TRP channels in mouse BMVECs and determined both EtOH concentration- and time-dependent effects on TRP expression using a PCR array. We also generated an in vitro BBB model to examine the involvement of a chosen TRP channel, TRP melastatin 7 (TRPM7), in EtOH-mediated alteration of BBB permeability. With the exception of the akyrin subfamily, members of five TRP subfamilies were expressed in mouse BMVECs, and their expression levels were modulated by EtOH in a concentration-dependent manner. In the in vitro BBB model, TRPM7 antagonists further enhanced EtOH-mediated alteration of BBB permeability. Because of the diversity of TRP channels in BMVECs that regulate cellular processes, EtOH can affect Ca2+/Mg2+ signaling, immune responses, lysosomal functions as well as BBB integrity.
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Ethanol Regulates Presynaptic Activity and Sedation through Presynaptic Unc13 Proteins in Drosophila. eNeuro 2018; 5:eN-NWR-0125-18. [PMID: 29911175 PMCID: PMC6001265 DOI: 10.1523/eneuro.0125-18.2018] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2018] [Revised: 05/09/2018] [Accepted: 05/12/2018] [Indexed: 11/21/2022] Open
Abstract
Ethanol has robust effects on presynaptic activity in many neurons, however, it is not yet clear how this drug acts within this compartment to change neural activity, nor the significance of this change on behavior and physiology in vivo. One possible presynaptic effector for ethanol is the Munc13-1 protein. Herein, we show that ethanol binding to the rat Munc13-1 C1 domain, at concentrations consistent with binge exposure, reduces diacylglycerol (DAG) binding. The inhibition of DAG binding is predicted to reduce the activity of Munc13-1 and presynaptic release. In Drosophila, we show that sedating concentrations of ethanol significantly reduce synaptic vesicle release in olfactory sensory neurons (OSNs), while having no significant impact on membrane depolarization and Ca2+ influx into the presynaptic compartment. These data indicate that ethanol targets the active zone in reducing synaptic vesicle exocytosis. Drosophila, haploinsufficent for the Munc13-1 ortholog Dunc13, are more resistant to the effect of ethanol on presynaptic inhibition. Genetically reducing the activity of Dunc13 through mutation or expression of RNAi transgenes also leads to a significant resistance to the sedative effects of ethanol. The neuronal expression of Munc13-1 in heterozygotes for a Dunc13 loss-of-function mutation can largely rescue the ethanol sedation resistance phenotype, indicating a conservation of function between Munc13-1 and Dunc13 in ethanol sedation. Hence, reducing Dunc13 activity leads to naïve physiological and behavioral resistance to sedating concentrations of ethanol. We propose that reducing Dunc13 activity, genetically or pharmacologically by ethanol binding to the C1 domain of Munc13-1/Dunc13, promotes a homeostatic response that leads to ethanol tolerance.
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Several behavioral traits relevant for alcoholism are controlled by ɣ2 subunit containing GABA A receptors on dopamine neurons in mice. Neuropsychopharmacology 2018; 43:1548-1556. [PMID: 29463910 PMCID: PMC5957272 DOI: 10.1038/s41386-018-0022-z] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/26/2017] [Revised: 01/22/2018] [Accepted: 01/23/2018] [Indexed: 12/28/2022]
Abstract
The risk factors for developing alcohol addiction include impulsivity, high sensitivity to the rewarding action of ethanol, and low sensitivity to its sedative and intoxicating effects. Genetic variation in GABAA receptor subunits, including the ɣ2 subunit (Gabrg2), affects the risk for developing alcoholism. Alcohol directly potentiates GABAA receptors and activates the mesolimbic dopamine system. Here, we deleted Gabrg2 selectively in dopamine cells of adult mice. The deletion resulted in elevated firing of dopamine neurons and made them less sensitive to drugs acting at GABAA receptors. At the behavioral level, the deletion increased exploratory behavior and augmented both correct and incorrect responding in the go/no-go task, a test often used to assay the response inhibition component of impulsivity. In addition, conditioned place preference to alcohol, but not to cocaine or morphine, was increased. Ethanol-induced locomotor activation was enhanced in the mice lacking Gabrg2 on dopaminergic cells, whereas the sedative effect of alcohol was reduced. Finally, the alcohol drinking, but not the alcohol preference, at a high concentration was increased in the mutant mice. In summary, deletion of Gabrg2 on dopamine cells induced several behavioral traits associated with high risk of developing alcoholism. The findings suggest that mice lacking Gabrg2 on dopaminergic cells could be used as models for individuals at high risk for developing alcoholism and that GABAA receptors on dopamine cells are protective against the development of excessive alcohol drinking.
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Autophagy as a compensation mechanism participates in ethanol-induced fetal adrenal dysfunction in female rats. Toxicol Appl Pharmacol 2018. [DOI: 10.1016/j.taap.2018.03.007] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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Structural basis for the ethanol action on G-protein-activated inwardly rectifying potassium channel 1 revealed by NMR spectroscopy. Proc Natl Acad Sci U S A 2018; 115:3858-3863. [PMID: 29581303 DOI: 10.1073/pnas.1722257115] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
Ethanol consumption leads to a wide range of pharmacological effects by acting on the signaling proteins in the human nervous system, such as ion channels. Despite its familiarity and biological importance, very little is known about the molecular mechanisms underlying the ethanol action, due to extremely weak binding affinity and the dynamic nature of the ethanol interaction. In this research, we focused on the primary in vivo target of ethanol, G-protein-activated inwardly rectifying potassium channel (GIRK), which is responsible for the ethanol-induced analgesia. By utilizing solution NMR spectroscopy, we characterized the changes in the structure and dynamics of GIRK induced by ethanol binding. We demonstrated here that ethanol binds to GIRK with an apparent dissociation constant of 1.0 M and that the actual physiological binding site of ethanol is located on the cavity formed between the neighboring cytoplasmic regions of the GIRK tetramer. From the methyl-based NMR relaxation analyses, we revealed that ethanol activates GIRK by shifting the conformational equilibrium processes, which are responsible for the gating of GIRK, to stabilize an open conformation of the cytoplasmic ion gate. We suggest that the dynamic molecular mechanism of the ethanol-induced activation of GIRK represents a general model of the ethanol action on signaling proteins in the human nervous system.
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Raškevičius V, Jotautis V, Rimkutė L, Marandykina A, Kazokaitė M, Kairys V, Skeberdis VA. Molecular basis for potentiation of Cx36 gap junction channel conductance by n-alcohols and general anesthetics. Biosci Rep 2018; 38:BSR20171323. [PMID: 29298877 PMCID: PMC5803492 DOI: 10.1042/bsr20171323] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2017] [Revised: 12/22/2017] [Accepted: 01/01/2018] [Indexed: 01/01/2023] Open
Abstract
In our recent study, we have demonstrated that short carbon chain n-alcohols (up to octanol) stimulated while long carbon chain n-alcohols inhibited the conductance of connexin (Cx) 36 (Cx36) gap junction (GJ) channels. In contrast, GJ channels composed of other types of Cxs all were inhibited by n-alcohols independent of their carbon chain length. To identify the putative structural domains of Cx36, responsible for the dual effect of n-alcohols, we performed structural modeling of Cx36 protein docking with hexanol and isoflurane that stimulated as well as nonanol and carbenoxolone that inhibited the conductance of Cx36 GJs and revealed their multiple common docking sites and a single pocket accessible only to hexanol and isoflurane. The pocket is located in the vicinity of three unique cysteine residues, namely C264 in the fourth, and C92 and C87 in the second transmembrane domain of the neighboring Cx36 subunits. To examine the hypothesis that disulphide bonding might be involved in the stimulatory effect of hexanol and isoflurane, we generated cysteine substitutions in Cx36 and demonstrated by a dual whole-cell patch-clamp technique that in HeLa (human cervix carcinoma cell line) and N2A (mouse neuroblastoma cell line) cells these mutations reversed the stimulatory effect of hexanol and isoflurane to inhibitory one, typical of other Cxs that lack respective cysteines and a specific docking pocket for these compounds. Our findings suggest that the stimulatory effect of hexanol and isoflurane on Cx36 GJ conductance could be achieved by re-shuffling of the inter-subunit disulphide bond between C264 and C92 to the intra-subunit one between C264 and C87.
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Affiliation(s)
- Vytautas Raškevičius
- Institute of Cardiology, Lithuanian University of Health Sciences, Kaunas LT-50162, Lithuania
| | - Vaidas Jotautis
- Institute of Cardiology, Lithuanian University of Health Sciences, Kaunas LT-50162, Lithuania
| | - Lina Rimkutė
- Institute of Cardiology, Lithuanian University of Health Sciences, Kaunas LT-50162, Lithuania
| | - Alina Marandykina
- Institute of Cardiology, Lithuanian University of Health Sciences, Kaunas LT-50162, Lithuania
| | - Mintautė Kazokaitė
- Institute of Cardiology, Lithuanian University of Health Sciences, Kaunas LT-50162, Lithuania
| | - Visvaldas Kairys
- Institute of Biotechnology, Vilnius University, Vilnius LT-10257, Lithuania
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Abrahao KP, Salinas AG, Lovinger DM. Alcohol and the Brain: Neuronal Molecular Targets, Synapses, and Circuits. Neuron 2017; 96:1223-1238. [PMID: 29268093 PMCID: PMC6566861 DOI: 10.1016/j.neuron.2017.10.032] [Citation(s) in RCA: 247] [Impact Index Per Article: 35.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2017] [Revised: 09/30/2017] [Accepted: 10/27/2017] [Indexed: 12/13/2022]
Abstract
Ethanol is one of the most commonly abused drugs. Although environmental and genetic factors contribute to the etiology of alcohol use disorders, it is ethanol's actions in the brain that explain (1) acute ethanol-related behavioral changes, such as stimulant followed by depressant effects, and (2) chronic changes in behavior, including escalated use, tolerance, compulsive seeking, and dependence. Our knowledge of ethanol use and abuse thus relies on understanding its effects on the brain. Scientists have employed both bottom-up and top-down approaches, building from molecular targets to behavioral analyses and vice versa, respectively. This review highlights current progress in the field, focusing on recent and emerging molecular, cellular, and circuit effects of the drug that impact ethanol-related behaviors. The focus of the field is now on pinpointing which molecular effects in specific neurons within a brain region contribute to behavioral changes across the course of acute and chronic ethanol exposure.
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Affiliation(s)
- Karina P Abrahao
- Laboratory for Integrative Neuroscience, Division of Intramural Clinical and Biological Research, National Institute on Alcohol Abuse and Alcoholism, NIH, Bethesda, MD 20892, USA
| | - Armando G Salinas
- Laboratory for Integrative Neuroscience, Division of Intramural Clinical and Biological Research, National Institute on Alcohol Abuse and Alcoholism, NIH, Bethesda, MD 20892, USA
| | - David M Lovinger
- Laboratory for Integrative Neuroscience, Division of Intramural Clinical and Biological Research, National Institute on Alcohol Abuse and Alcoholism, NIH, Bethesda, MD 20892, USA.
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Söderpalm B, Lidö HH, Ericson M. The Glycine Receptor-A Functionally Important Primary Brain Target of Ethanol. Alcohol Clin Exp Res 2017; 41:1816-1830. [PMID: 28833225 DOI: 10.1111/acer.13483] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2017] [Accepted: 08/15/2017] [Indexed: 12/27/2022]
Abstract
Identification of ethanol's (EtOH) primary molecular brain targets and determination of their functional role is an ongoing, important quest. Pentameric ligand-gated ion channels, that is, the nicotinic acetylcholine receptor, the γ-aminobutyric acid type A receptor, the 5-hydroxytryptamine3 , and the glycine receptor (GlyR), are such targets. Here, aspects of the structure and function of these receptors and EtOH's interaction with them are briefly reviewed, with special emphasis on the GlyR and the importance of this receptor and its ligands for EtOH pharmacology. It is suggested that GlyRs are involved in (i) the dopamine-activating effect of EtOH, (ii) regulating EtOH intake, and (iii) the relapse preventing effect of acamprosate. Exploration of the GlyR subtypes involved and efforts to develop subtype specific agonists or antagonists may offer new pharmacotherapies for alcohol use disorders.
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Affiliation(s)
- Bo Söderpalm
- Addiction Biology Unit, Department of Psychiatry and Neurochemistry, Institute of Neuroscience and Physiology, the Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden
| | - Helga H Lidö
- Addiction Biology Unit, Department of Psychiatry and Neurochemistry, Institute of Neuroscience and Physiology, the Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden
| | - Mia Ericson
- Addiction Biology Unit, Department of Psychiatry and Neurochemistry, Institute of Neuroscience and Physiology, the Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden
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49
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Low dose of alcohol attenuates pro-atherosclerotic activity of thrombin. Atherosclerosis 2017; 265:215-224. [DOI: 10.1016/j.atherosclerosis.2017.09.005] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/03/2017] [Revised: 07/29/2017] [Accepted: 09/01/2017] [Indexed: 01/11/2023]
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50
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Ethanol Stimulates Locomotion via a G αs-Signaling Pathway in IL2 Neurons in Caenorhabditis elegans. Genetics 2017; 207:1023-1039. [PMID: 28951527 PMCID: PMC5676223 DOI: 10.1534/genetics.117.300119] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2017] [Accepted: 09/23/2017] [Indexed: 01/21/2023] Open
Abstract
Alcohol abuse is among the top causes of preventable death, generating considerable financial, health, and societal burdens. Paradoxically, alcohol... Alcohol is a potent pharmacological agent when consumed acutely at sufficient quantities and repeated overuse can lead to addiction and deleterious effects on health. Alcohol is thought to modulate neuronal function through low-affinity interactions with proteins, in particular with membrane channels and receptors. Paradoxically, alcohol acts as both a stimulant and a sedative. The exact molecular mechanisms for the acute effects of ethanol on neurons, as either a stimulant or a sedative, however remain unclear. We investigated the role that the heat shock transcription factor HSF-1 played in determining a stimulatory phenotype of Caenorhabditis elegans in response to physiologically relevant concentrations of ethanol (17 mM; 0.1% v/v). Using genetic techniques, we demonstrate that either RNA interference of hsf-1 or use of an hsf-1(sy441) mutant lacked the enhancement of locomotion in response to acute ethanol exposure evident in wild-type animals. We identify that the requirement for HSF-1 in this phenotype was IL2 neuron-specific and required the downstream expression of the α-crystallin ortholog HSP-16.48. Using a combination of pharmacology, optogenetics, and phenotypic analyses we determine that ethanol activates a Gαs-cAMP-protein kinase A signaling pathway in IL2 neurons to stimulate nematode locomotion. We further implicate the phosphorylation of a specific serine residue (Ser322) on the synaptic protein UNC-18 as an end point for the Gαs-dependent signaling pathway. These findings establish and characterize a distinct neurosensory cell signaling pathway that determines the stimulatory action of ethanol and identifies HSP-16.48 and HSF-1 as novel regulators of this pathway.
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