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San Martin LS, Armijo-Weingart L, Gallegos S, Araya A, Homanics GE, Aguayo LG. Changes in ethanol effects in knock-in mice expressing ethanol insensitive alpha1 and alpha2 glycine receptor subunits. Life Sci 2024; 348:122673. [PMID: 38679193 DOI: 10.1016/j.lfs.2024.122673] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2023] [Revised: 04/22/2024] [Accepted: 04/24/2024] [Indexed: 05/01/2024]
Abstract
AIMS Glycine receptors (GlyRs) are potentiated by physiologically relevant concentrations of ethanol, and mutations in the intracellular loop of α1 and α2 subunits reduced the effect of the drug. Knock-in (KI) mice having these individual mutations revealed that α1 and α2 subunits played a role in ethanol-induced sedation and ethanol intake. In this study, we wanted to examine if the effects of stacking both mutations in a 2xKI mouse model (α1/α2) generated by a selective breeding strategy further impacted cellular and behavioral responses to ethanol. MAIN METHODS We used electrophysiological recordings to examine ethanol's effect on GlyRs and evaluated ethanol-induced neuronal activation using c-Fos immunoreactivity and the genetically encoded calcium indicator GCaMP6s in the nucleus accumbens (nAc). We also examined ethanol-induced behavior using open field, loss of the righting response, and drinking in the dark (DID) paradigm. KEY FINDINGS Ethanol did not potentiate GlyRs nor affect neuronal excitability in the nAc from 2xKI. Moreover, ethanol decreased the Ca2+ signal in WT mice, whereas there were no changes in the signal in 2xKI mice. Interestingly, there was an increase in c-Fos baseline in the 2xKI mice in the absence of ethanol. Behavioral assays showed that 2xKI mice recovered faster from a sedative dose of ethanol and had higher ethanol intake on the first test day of the DID test than WT mice. Interestingly, an open-field assay showed that 2xKI mice displayed less anxiety-like behavior than WT mice. SIGNIFICANCE The results indicate that α1 and α2 subunits are biologically relevant targets for regulating sedative effects and ethanol consumption.
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Affiliation(s)
- Loreto S San Martin
- Laboratory of Neurophysiology, Department of Physiology, Universidad de Concepción, Chile; Programa de Neurociencia, Psiquiatría y Salud Mental (NEPSAM), Universidad de Concepción, Chile
| | - Lorena Armijo-Weingart
- Laboratory of Neurophysiology, Department of Physiology, Universidad de Concepción, Chile; Programa de Neurociencia, Psiquiatría y Salud Mental (NEPSAM), Universidad de Concepción, Chile
| | - Scarlet Gallegos
- Laboratory of Neurophysiology, Department of Physiology, Universidad de Concepción, Chile
| | - Anibal Araya
- Laboratory of Neurophysiology, Department of Physiology, Universidad de Concepción, Chile
| | - Gregg E Homanics
- Department of Anesthesiology and Perioperative Medicine, University of Pittsburgh, Pittsburgh, PA, USA; Department of Pharmacology & Chemical, University of Pittsburgh, Pittsburgh, PA, USA; Department of Biology, University of Pittsburgh, Pittsburgh, PA, USA; Department of Neurobiology, University of Pittsburgh, Pittsburgh, PA, USA
| | - Luis G Aguayo
- Laboratory of Neurophysiology, Department of Physiology, Universidad de Concepción, Chile; Programa de Neurociencia, Psiquiatría y Salud Mental (NEPSAM), Universidad de Concepción, Chile.
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Homanics GE, Park JE, Bailey L, Schaeffer DJ, Schaeffer L, He J, Li S, Zhang T, Haber A, Spruce C, Greenwood A, Murai T, Schultz L, Mongeau L, Ha S, Oluoch J, Stein B, Choi SH, Huhe H, Thathiah A, Strick PL, Carter GW, Silva AC, Sukoff Rizzo SJ. Early molecular events of autosomal-dominant Alzheimer's disease in marmosets with PSEN1 mutations. Alzheimers Dement 2024; 20:3455-3471. [PMID: 38574388 PMCID: PMC11095452 DOI: 10.1002/alz.13806] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2023] [Revised: 02/27/2024] [Accepted: 02/28/2024] [Indexed: 04/06/2024]
Abstract
INTRODUCTION Fundamental questions remain about the key mechanisms that initiate Alzheimer's disease (AD) and the factors that promote its progression. Here we report the successful generation of the first genetically engineered marmosets that carry knock-in (KI) point mutations in the presenilin 1 (PSEN1) gene that can be studied from birth throughout lifespan. METHODS CRISPR/Cas9 was used to generate marmosets with C410Y or A426P point mutations in PSEN1. Founders and their germline offspring are comprehensively studied longitudinally using non-invasive measures including behavior, biomarkers, neuroimaging, and multiomics signatures. RESULTS Prior to adulthood, increases in plasma amyloid beta were observed in PSEN1 mutation carriers relative to non-carriers. Analysis of brain revealed alterations in several enzyme-substrate interactions within the gamma secretase complex prior to adulthood. DISCUSSION Marmosets carrying KI point mutations in PSEN1 provide the opportunity to study the earliest primate-specific mechanisms that contribute to the molecular and cellular root causes of AD onset and progression. HIGHLIGHTS We report the successful generation of genetically engineered marmosets harboring knock-in point mutations in the PSEN1 gene. PSEN1 marmosets and their germline offspring recapitulate the early emergence of AD-related biomarkers. Studies as early in life as possible in PSEN1 marmosets will enable the identification of primate-specific mechanisms that drive disease progression.
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Affiliation(s)
- Gregg E. Homanics
- Department of Anesthesiology & Perioperative MedicineUniversity of Pittsburgh School of MedicinePittsburghPennsylvaniaUSA
- Department of NeurobiologyUniversity of Pittsburgh Brain InstituteUniversity of Pittsburgh School of MedicinePittsburghPennsylvaniaUSA
| | - Jung Eun Park
- Department of NeurobiologyUniversity of Pittsburgh Brain InstituteUniversity of Pittsburgh School of MedicinePittsburghPennsylvaniaUSA
| | - Lauren Bailey
- Department of MedicineUniversity of Pittsburgh Aging Institute, University of Pittsburgh School of MedicinePittsburghPennsylvaniaUSA
| | - David J. Schaeffer
- Department of NeurobiologyUniversity of Pittsburgh Brain InstituteUniversity of Pittsburgh School of MedicinePittsburghPennsylvaniaUSA
| | - Lauren Schaeffer
- Department of NeurobiologyUniversity of Pittsburgh Brain InstituteUniversity of Pittsburgh School of MedicinePittsburghPennsylvaniaUSA
| | - Jie He
- Department of StatisticsUniversity of Pittsburgh School of MedicinePittsburghPennsylvaniaUSA
| | - Shuoran Li
- Department of StatisticsUniversity of Pittsburgh School of MedicinePittsburghPennsylvaniaUSA
| | - Tingting Zhang
- Department of StatisticsUniversity of Pittsburgh School of MedicinePittsburghPennsylvaniaUSA
| | | | | | | | - Takeshi Murai
- Department of MedicineUniversity of Pittsburgh Aging Institute, University of Pittsburgh School of MedicinePittsburghPennsylvaniaUSA
| | - Laura Schultz
- Department of MedicineUniversity of Pittsburgh Aging Institute, University of Pittsburgh School of MedicinePittsburghPennsylvaniaUSA
| | - Lauren Mongeau
- Department of MedicineUniversity of Pittsburgh Aging Institute, University of Pittsburgh School of MedicinePittsburghPennsylvaniaUSA
| | - Seung‐Kwon Ha
- Department of NeurobiologyUniversity of Pittsburgh Brain InstituteUniversity of Pittsburgh School of MedicinePittsburghPennsylvaniaUSA
| | - Julia Oluoch
- Department of NeurobiologyUniversity of Pittsburgh Brain InstituteUniversity of Pittsburgh School of MedicinePittsburghPennsylvaniaUSA
| | - Brianne Stein
- Department of NeurobiologyUniversity of Pittsburgh Brain InstituteUniversity of Pittsburgh School of MedicinePittsburghPennsylvaniaUSA
| | - Sang Ho Choi
- Department of NeurobiologyUniversity of Pittsburgh Brain InstituteUniversity of Pittsburgh School of MedicinePittsburghPennsylvaniaUSA
| | - Hasi Huhe
- Department of MedicineUniversity of Pittsburgh Aging Institute, University of Pittsburgh School of MedicinePittsburghPennsylvaniaUSA
| | - Amantha Thathiah
- Department of NeurobiologyUniversity of Pittsburgh Brain InstituteUniversity of Pittsburgh School of MedicinePittsburghPennsylvaniaUSA
| | - Peter L. Strick
- Department of NeurobiologyUniversity of Pittsburgh Brain InstituteUniversity of Pittsburgh School of MedicinePittsburghPennsylvaniaUSA
| | | | - Afonso C. Silva
- Department of NeurobiologyUniversity of Pittsburgh Brain InstituteUniversity of Pittsburgh School of MedicinePittsburghPennsylvaniaUSA
| | - Stacey J. Sukoff Rizzo
- Department of NeurobiologyUniversity of Pittsburgh Brain InstituteUniversity of Pittsburgh School of MedicinePittsburghPennsylvaniaUSA
- Department of MedicineUniversity of Pittsburgh Aging Institute, University of Pittsburgh School of MedicinePittsburghPennsylvaniaUSA
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Dilly GA, Blednov YA, Warden AS, Ezerskiy L, Fleischer C, Plotkin JD, Patil S, Osterndorff-Kahanek EA, Mayfield J, Mayfield RD, Homanics GE, Messing RO. Knockdown of Tlr3 in dorsal striatum reduces ethanol consumption and acute functional tolerance in male mice. Brain Behav Immun 2024; 118:437-448. [PMID: 38499210 PMCID: PMC11007683 DOI: 10.1016/j.bbi.2024.03.021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/16/2023] [Revised: 03/05/2024] [Accepted: 03/15/2024] [Indexed: 03/20/2024] Open
Abstract
Systemic activation of toll-like receptor 3 (TLR3) signaling using poly(I:C), a TLR3 agonist, drives ethanol consumption in several rodent models, while global knockout of Tlr3 reduces drinking in C57BL/6J male mice. To determine if brain TLR3 pathways are involved in drinking behavior, we used CRISPR/Cas9 genome editing to generate a Tlr3 floxed (Tlr3F/F) mouse line. After sequence confirmation and functional validation of Tlr3 brain transcripts, we injected Tlr3F/F male mice with an adeno-associated virus expressing Cre recombinase (AAV5-CMV-Cre-GFP) to knockdown Tlr3 in the medial prefrontal cortex, nucleus accumbens, or dorsal striatum (DS). Only Tlr3 knockdown in the DS decreased two-bottle choice, every-other-day (2BC-EOD) ethanol consumption. DS-specific deletion of Tlr3 also increased intoxication and prevented acute functional tolerance to ethanol. In contrast, poly(I:C)-induced activation of TLR3 signaling decreased intoxication in male C57BL/6J mice, consistent with its ability to increase 2BC-EOD ethanol consumption in these mice. We also found that TLR3 was highly colocalized with DS neurons. AAV5-Cre transfection occurred predominantly in neurons, but there was minimal transfection in astrocytes and microglia. Collectively, our previous and current studies show that activating or inhibiting TLR3 signaling produces opposite effects on acute responses to ethanol and on ethanol consumption. While previous studies, however, used global knockout or systemic TLR3 activation (which alter peripheral and brain innate immune responses), the current results provide new evidence that brain TLR3 signaling regulates ethanol drinking. We propose that activation of TLR3 signaling in DS neurons increases ethanol consumption and that a striatal TLR3 pathway is a potential target to reduce excessive drinking.
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Affiliation(s)
- Geoffrey A Dilly
- Waggoner Center for Alcohol and Addiction Research, The University of Texas at Austin, Austin, TX 78712, United States; Institute for Neuroscience, The University of Texas at Austin, Austin, TX 78712, United States; Department of Neuroscience, The University of Texas at Austin, Austin, TX 78712, United States; Department of Neurology, Dell Medical School, The University of Texas at Austin, Austin, TX 78712, United States
| | - Yuri A Blednov
- Waggoner Center for Alcohol and Addiction Research, The University of Texas at Austin, Austin, TX 78712, United States
| | - Anna S Warden
- Waggoner Center for Alcohol and Addiction Research, The University of Texas at Austin, Austin, TX 78712, United States
| | - Lubov Ezerskiy
- Waggoner Center for Alcohol and Addiction Research, The University of Texas at Austin, Austin, TX 78712, United States; Department of Neuroscience, The University of Texas at Austin, Austin, TX 78712, United States
| | - Caleb Fleischer
- Waggoner Center for Alcohol and Addiction Research, The University of Texas at Austin, Austin, TX 78712, United States; Department of Neuroscience, The University of Texas at Austin, Austin, TX 78712, United States
| | - Jesse D Plotkin
- Waggoner Center for Alcohol and Addiction Research, The University of Texas at Austin, Austin, TX 78712, United States; Department of Neuroscience, The University of Texas at Austin, Austin, TX 78712, United States
| | - Shruti Patil
- Waggoner Center for Alcohol and Addiction Research, The University of Texas at Austin, Austin, TX 78712, United States
| | | | - Jody Mayfield
- Waggoner Center for Alcohol and Addiction Research, The University of Texas at Austin, Austin, TX 78712, United States
| | - R Dayne Mayfield
- Waggoner Center for Alcohol and Addiction Research, The University of Texas at Austin, Austin, TX 78712, United States; Department of Neuroscience, The University of Texas at Austin, Austin, TX 78712, United States
| | - Gregg E Homanics
- Departments of Anesthesiology & Perioperative Medicine, Neurobiology, and Pharmacology & Chemical Biology, University of Pittsburgh, Pittsburgh, PA 15261, United States
| | - Robert O Messing
- Waggoner Center for Alcohol and Addiction Research, The University of Texas at Austin, Austin, TX 78712, United States; Institute for Neuroscience, The University of Texas at Austin, Austin, TX 78712, United States; Department of Neuroscience, The University of Texas at Austin, Austin, TX 78712, United States; Department of Neurology, Dell Medical School, The University of Texas at Austin, Austin, TX 78712, United States.
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Rice RC, Gil DV, Baratta AM, Frawley RR, Hill SY, Farris SP, Homanics GE. Inter- and transgenerational heritability of preconception chronic stress or alcohol exposure: Translational outcomes in brain and behavior. Neurobiol Stress 2024; 29:100603. [PMID: 38234394 PMCID: PMC10792982 DOI: 10.1016/j.ynstr.2023.100603] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2023] [Revised: 12/18/2023] [Accepted: 12/19/2023] [Indexed: 01/19/2024] Open
Abstract
Chronic stress and alcohol (ethanol) use are highly interrelated and can change an individual's behavior through molecular adaptations that do not change the DNA sequence, but instead change gene expression. A recent wealth of research has found that these nongenomic changes can be transmitted across generations, which could partially account for the "missing heritability" observed in genome-wide association studies of alcohol use disorder and other stress-related neuropsychiatric disorders. In this review, we summarize the molecular and behavioral outcomes of nongenomic inheritance of chronic stress and ethanol exposure and the germline mechanisms that could give rise to this heritability. In doing so, we outline the need for further research to: (1) Investigate individual germline mechanisms of paternal, maternal, and biparental nongenomic chronic stress- and ethanol-related inheritance; (2) Synthesize and dissect cross-generational chronic stress and ethanol exposure; (3) Determine cross-generational molecular outcomes of preconception ethanol exposure that contribute to alcohol-related disease risk, using cancer as an example. A detailed understanding of the cross-generational nongenomic effects of stress and/or ethanol will yield novel insight into the impact of ancestral perturbations on disease risk across generations and uncover actionable targets to improve human health.
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Affiliation(s)
- Rachel C. Rice
- Center for Neuroscience at the University of Pittsburgh, Pittsburgh, PA, USA
| | - Daniela V. Gil
- Center for Neuroscience at the University of Pittsburgh, Pittsburgh, PA, USA
| | - Annalisa M. Baratta
- Center for Neuroscience at the University of Pittsburgh, Pittsburgh, PA, USA
| | - Remy R. Frawley
- Department of Anesthesiology and Perioperative Medicine, University of Pittsburgh, Pittsburgh, PA, USA
| | - Shirley Y. Hill
- Department of Psychiatry, University of Pittsburgh, Pittsburgh, PA, USA
- Department of Psychology, University of Pittsburgh, Pittsburgh, PA, USA
- Department of Human Genetics, School of Public Health, University of Pittsburgh, Pittsburgh, PA, USA
| | - Sean P. Farris
- Center for Neuroscience at the University of Pittsburgh, Pittsburgh, PA, USA
- Department of Anesthesiology and Perioperative Medicine, University of Pittsburgh, Pittsburgh, PA, USA
- Department of Biomedical Informatics, University of Pittsburgh, Pittsburgh, PA, USA
| | - Gregg E. Homanics
- Center for Neuroscience at the University of Pittsburgh, Pittsburgh, PA, USA
- Department of Anesthesiology and Perioperative Medicine, University of Pittsburgh, Pittsburgh, PA, USA
- Department of Pharmacology and Chemical Biology, University of Pittsburgh, Pittsburgh, PA, USA
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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 2023:10.1038/s41380-023-02346-y. [PMID: 38135755 DOI: 10.1038/s41380-023-02346-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [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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Kambali M, Li Y, Unichenko P, Pliego JF, Yadav R, Liu J, McGuinness P, Cobb JG, Wang M, Nagarajan R, Lyu J, Vongsouthi V, Jackson CJ, Engin E, Coyle JT, Shin J, Talkowski ME, Homanics GE, Bolshakov VY, Henneberger C, Rudolph U. A marker chromosome in psychosis identifies glycine decarboxylase (GLDC) as a novel regulator of neuronal and synaptic function in the hippocampus. bioRxiv 2023:2023.05.29.542745. [PMID: 37398055 PMCID: PMC10312439 DOI: 10.1101/2023.05.29.542745] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/04/2023]
Abstract
The biological significance of a small supernumerary marker chromosome that results in dosage alterations to chromosome 9p24.1, including triplication of the GLDC gene encoding glycine decarboxylase, in two patients with psychosis is unclear. In an allelic series of copy number variant mouse models, we identify that triplication of Gldc reduces extracellular glycine levels as determined by optical fluorescence resonance energy transfer (FRET) in dentate gyrus (DG) but not in CA1, suppresses long-term potentiation (LTP) in mPP-DG synapses but not in CA3-CA1 synapses, reduces the activity of biochemical pathways implicated in schizophrenia and mitochondrial bioenergetics, and displays deficits in prepulse inhibition, startle habituation, latent inhibition, working memory, sociability and social preference. Our results thus provide a link between a genomic copy number variation, biochemical, cellular and behavioral phenotypes, and further demonstrate that GLDC negatively regulates long-term synaptic plasticity at specific hippocampal synapses, possibly contributing to the development of neuropsychiatric disorders.
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Plasil SL, Collins VJ, Baratta AM, Farris SP, Homanics GE. Hippocampal ceRNA networks from chronic intermittent ethanol vapor-exposed male mice and functional analysis of top-ranked lncRNA genes for ethanol drinking phenotypes. Adv Drug Alcohol Res 2022; 2:10831. [PMID: 36908580 PMCID: PMC10004261 DOI: 10.3389/adar.2022.10831] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The molecular mechanisms regulating the development and progression of alcohol use disorder (AUD) are largely unknown. While noncoding RNAs have previously been implicated as playing key roles in AUD, long-noncoding RNA (lncRNA) remains understudied in relation to AUD. In this study, we first identified ethanol-responsive lncRNAs in the mouse hippocampus that are transcriptional network hub genes. Microarray analysis of lncRNA, miRNA, circular RNA, and protein coding gene expression in the hippocampus from chronic intermittent ethanol vapor- or air- (control) exposed mice was used to identify ethanol-responsive competing endogenous RNA (ceRNA) networks. Highly interconnected lncRNAs (genes that had the strongest overall correlation to all other dysregulated genes identified) were ranked. The top four lncRNAs were novel, previously uncharacterized genes named Gm42575, 4930413E15Rik, Gm15767, and Gm33447, hereafter referred to as Pitt1, Pitt2, Pitt3, and Pitt4, respectively. We subsequently tested the hypothesis that CRISPR/Cas9 mutagenesis of the putative promoter and first exon of these lncRNAs in C57BL/6J mice would alter ethanol drinking behavior. The Drinking in the Dark (DID) assay was used to examine binge-like drinking behavior, and the Every-Other-Day Two-Bottle Choice (EOD-2BC) assay was used to examine intermittent ethanol consumption and preference. No significant differences between control and mutant mice were observed in the DID assay. Female-specific reductions in ethanol consumption were observed in the EOD-2BC assay for Pitt1, Pitt3, and Pitt4 mutant mice compared to controls. Male-specific alterations in ethanol preference were observed for Pitt1 and Pitt2. Female-specific increases in ethanol preference were observed for Pitt3 and Pitt4. Total fluid consumption was reduced in Pitt1 and Pitt2 mutants at 15% v/v ethanol and in Pitt3 and Pitt4 at 20% v/v ethanol in females only. We conclude that all lncRNAs targeted altered ethanol drinking behavior, and that lncRNAs Pitt1, Pitt3, and Pitt4 influenced ethanol consumption in a sex-specific manner. Further research is necessary to elucidate the biological mechanisms for these effects. These findings add to the literature implicating noncoding RNAs in AUD and suggest lncRNAs also play an important regulatory role in the disease.
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Affiliation(s)
- SL Plasil
- Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States
| | - VJ Collins
- Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States
| | - AM Baratta
- Center for Neuroscience, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States
| | - SP Farris
- Center for Neuroscience, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States
- Department of Anesthesiology and Perioperative Medicine, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States
- Department of Biomedical Informatics, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States
| | - GE Homanics
- Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States
- Center for Neuroscience, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States
- Department of Anesthesiology and Perioperative Medicine, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States
- Department of Neurobiology, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States
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Rizzo SJS, Choi S, Huhe H, Kofler J, Schaeffer D, Murai T, Hachem S, Karavolis M, Mou Y, Ha S, Carter GW, Park JE, Homanics GE, Strick PL, Silva AC. Differential brain expression of 3R and 4R Tau isoforms in aging wild‐type and young genetically engineered PSEN1 mutant marmosets. Alzheimers Dement 2022. [DOI: 10.1002/alz.069206] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Affiliation(s)
| | - Sang‐Ho Choi
- University of Pittsburgh School of Medicine Pittsburgh PA USA
| | - Hasi Huhe
- University of Pittsburgh School of Medicine Pittsburgh PA USA
| | - Julia Kofler
- University of Pittsburgh School of Medicine Pittsburgh PA USA
| | - David Schaeffer
- University of Pittsburgh School of Medicine Pittsburgh PA USA
| | - Takeshi Murai
- University of Pittsburgh School of Medicine Pittsburgh PA USA
| | | | | | - Yongshan Mou
- University of Pittsburgh School of Medicine Pittsburgh PA USA
| | - Seung‐Kwon Ha
- University of Pittsburgh School of Medicine Pittsburgh PA USA
| | | | - Jung Eun Park
- University of Pittsburgh School of Medicine Pittsburgh PA USA
| | | | - Peter L Strick
- University of Pittsburgh School of Medicine Pittsburgh PA USA
| | - Afonso C Silva
- University of Pittsburgh School of Medicine Pittsburgh PA USA
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Baratta AM, Mangieri RA, Aziz HC, Lopez MF, Farris SP, Homanics GE. Effect of chronic intermittent ethanol vapor exposure on RNA content of brain-derived extracellular vesicles. Alcohol 2022; 105:9-24. [PMID: 36055466 PMCID: PMC10173183 DOI: 10.1016/j.alcohol.2022.08.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2022] [Revised: 08/18/2022] [Accepted: 08/18/2022] [Indexed: 01/26/2023]
Abstract
Extracellular vesicles (EVs) are important players in normal biological function and disease pathogenesis. Of the many biomolecules packaged into EVs, coding and noncoding RNA transcripts are of particular interest for their ability to significantly alter cellular and molecular processes. Here we investigate how chronic ethanol exposure impacts EV RNA cargo and the functional outcomes of these changes. Following chronic intermittent ethanol (CIE) vapor exposure, EVs were isolated from male and female C57BL/6J mouse brain. Total RNA from EVs was analyzed by lncRNA/mRNA microarray to survey changes in RNA cargo following vapor exposure. Differential expression analysis of microarray data revealed a number of lncRNA and mRNA types differentially expressed in CIE compared to control EVs. Weighted gene co-expression network analysis identified multiple male and female specific modules related to neuroinflammation, cell death, demyelination, and synapse organization. To functionally test these changes, whole-cell voltage-clamp recordings were used to assess synaptic transmission. Incubation of nucleus accumbens brain slices with EVs led to a reduction in spontaneous excitatory postsynaptic current amplitude, although no changes in synaptic transmission were observed between control and CIE EV administration. These results indicate that CIE vapor exposure significantly changes the RNA cargo of brain-derived EVs, which have the ability to impact neuronal function.
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Affiliation(s)
- Annalisa M Baratta
- Center for Neuroscience, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, United States
| | - Regina A Mangieri
- College of Pharmacy, University of Texas at Austin, Texas, United States
| | - Heather C Aziz
- College of Pharmacy, University of Texas at Austin, Texas, United States
| | - Marcelo F Lopez
- Department of Psychiatry and Behavioral Science, Charleston Alcohol Research Center, Medical University of South Carolina, Charleston, South Carolina, United States
| | - Sean P Farris
- Center for Neuroscience, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, United States; Department of Anesthesiology and Perioperative Medicine, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, United States; Department of Biomedical Informatics, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, United States
| | - Gregg E Homanics
- Center for Neuroscience, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, United States; Department of Anesthesiology and Perioperative Medicine, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, United States; Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, United States; Department of Neurobiology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, United States.
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10
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Myers TD, Ferguson C, Gliniak E, Homanics GE, Palladino MJ. Murine model of triosephosphate isomerase deficiency with anemia and severe neuromuscular dysfunction. Curr Res Neurobiol 2022; 3:100062. [PMID: 36405628 PMCID: PMC9673098 DOI: 10.1016/j.crneur.2022.100062] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2022] [Revised: 09/30/2022] [Accepted: 10/30/2022] [Indexed: 11/10/2022] Open
Abstract
Triosephosphate isomerase deficiency (TPI Df) is a rare, aggressive genetic disease that typically affects young children and currently has no established treatment. TPI Df is characterized by hemolytic anemia, progressive neuromuscular degeneration, and a markedly reduced lifespan. The disease has predominately been studied using invertebrate and in vitro models, which lack key aspects of the human disease. While other groups have generated mammalian Tpi1 mutant strains, specifically with the mouse mus musculus, these do not recapitulate key characteristic phenotypes of the human disease. Reported here is the generation of a novel murine model of TPI Df. CRISPR-Cas9 was utilized to engineer the most common human disease-causing mutation, Tpi1 E105D , and Tpi1 null mice were also isolated as a frame-shifting deletion. Tpi1 E105D/null mice experience a markedly shortened lifespan, postural abnormalities consistent with extensive neuromuscular dysfunction, hemolytic anemia, pathological changes in spleen, and decreased body weight. There is a ∼95% reduction in TPI protein levels in Tpi1 E105D/null animals compared to wild-type littermates, consistent with decreased TPI protein stability, a known cause of TPI Df. This work illustrates the capability of Tpi1 E105D/null mice to serve as a mammalian model of human TPI Df. This work will allow for advancement in the study of TPI Df within a model with physiology similar to humans. The development of the model reported here will enable mechanistic studies of disease pathogenesis and, importantly, efficacy testing in a mammalian system for emerging TPI Df treatments.
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Key Words
- CRISPR
- DHAP, Dihydroxyacetone phosphate
- G3P, Glyceraldehyde-3-phosphate
- Genetics
- Glycolysis
- Hct, Hematocrit
- Hgb, Hemoglobin
- Hsp70, Heat shock protein 70
- Hsp90, Heat shock protein 90
- MCV, Mean Corpuscular Volume
- Metabolism
- RNAi, RNA interference
- TPI Deficiency
- TPI Df, Triosephosphate Isomerase Deficiency
- TPI, Triosephosphate Isomerase
- Triosephosphate isomerase (TPI)
- UTR, Untranslated Region
- WT, Wild-type
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Affiliation(s)
- Tracey D. Myers
- Center for Neuroscience, University of Pittsburgh, Pittsburgh, PA, USA
- Department of Pharmacology and Chemical Biology, University of Pittsburgh, Pittsburgh, PA, USA
- Pittsburgh Institute for Neurodegenerative Diseases, University of Pittsburgh, Pittsburgh, PA, USA
| | - Carolyn Ferguson
- Department of Anesthesiology and Preoperative Medicine, University of Pittsburgh, Pittsburgh, PA, USA
| | - Eric Gliniak
- Department of Pharmacology and Chemical Biology, University of Pittsburgh, Pittsburgh, PA, USA
- Pittsburgh Institute for Neurodegenerative Diseases, University of Pittsburgh, Pittsburgh, PA, USA
| | - Gregg E. Homanics
- Center for Neuroscience, University of Pittsburgh, Pittsburgh, PA, USA
- Department of Pharmacology and Chemical Biology, University of Pittsburgh, Pittsburgh, PA, USA
- Department of Anesthesiology and Preoperative Medicine, University of Pittsburgh, Pittsburgh, PA, USA
- Department of Neurobiology, University of Pittsburgh, Pittsburgh, PA, USA
| | - Michael J. Palladino
- Center for Neuroscience, University of Pittsburgh, Pittsburgh, PA, USA
- Department of Pharmacology and Chemical Biology, University of Pittsburgh, Pittsburgh, PA, USA
- Pittsburgh Institute for Neurodegenerative Diseases, University of Pittsburgh, Pittsburgh, PA, USA
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11
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Huang Y, Rafael Guimarães T, Todd N, Ferguson C, Weiss KM, Stauffer FR, McDermott B, Hurtle BT, Saito T, Saido TC, MacDonald ML, Homanics GE, Thathiah A. G protein-biased GPR3 signaling ameliorates amyloid pathology in a preclinical Alzheimer's disease mouse model. Proc Natl Acad Sci U S A 2022; 119:e2204828119. [PMID: 36161942 PMCID: PMC9546571 DOI: 10.1073/pnas.2204828119] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2022] [Accepted: 08/01/2022] [Indexed: 11/24/2022] Open
Abstract
Biased G protein-coupled receptor (GPCR) ligands, which preferentially activate G protein or β-arrestin signaling pathways, are leading to the development of drugs with superior efficacy and reduced side effects in heart disease, pain management, and neuropsychiatric disorders. Although GPCRs are implicated in the pathophysiology of Alzheimer's disease (AD), biased GPCR signaling is a largely unexplored area of investigation in AD. Our previous work demonstrated that GPR3-mediated β-arrestin signaling modulates amyloid-β (Aβ) generation in vitro and that Gpr3 deficiency ameliorates Aβ pathology in vivo. However, Gpr3-deficient mice display several adverse phenotypes, including elevated anxiety-like behavior, reduced fertility, and memory impairment, which are potentially associated with impaired G protein signaling. Here, we generated a G protein-biased GPR3 mouse model to investigate the physiological and pathophysiological consequences of selective elimination of GPR3-mediated β-arrestin signaling in vivo. In contrast to Gpr3-deficient mice, G protein-biased GPR3 mice do not display elevated anxiety levels, reduced fertility, or cognitive impairment. We further determined that G protein-biased signaling reduces soluble Aβ levels and leads to a decrease in the area and compaction of amyloid plaques in the preclinical AppNL-G-F AD mouse model. The changes in amyloid pathology are accompanied by robust microglial and astrocytic hypertrophy, which suggest a protective glial response that may limit amyloid plaque development in G protein-biased GPR3 AD mice. Collectively, these studies indicate that GPR3-mediated G protein and β-arrestin signaling produce discrete and separable effects and provide proof of concept for the development of safer GPCR-targeting therapeutics with more directed pharmacological action for AD.
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Affiliation(s)
- Yunhong Huang
- Department of Neurobiology, University of Pittsburgh, Pittsburgh, PA,15260
| | - Thais Rafael Guimarães
- Department of Neurobiology, University of Pittsburgh, Pittsburgh, PA,15260
- Center for Neuroscience, University of Pittsburgh, Pittsburgh, PA,15260
| | - Nicholas Todd
- Department of Neurobiology, University of Pittsburgh, Pittsburgh, PA,15260
- Graduate Program in Molecular Pharmacology, University of Pittsburgh, Pittsburgh, PA, 15260
| | - Carolyn Ferguson
- Department of Anesthesiology & Perioperative Medicine, University of Pittsburgh, Pittsburgh, PA, 15260
| | - Kathryn M. Weiss
- Department of Neurobiology, University of Pittsburgh, Pittsburgh, PA,15260
| | - Fiona R. Stauffer
- Department of Neurobiology, University of Pittsburgh, Pittsburgh, PA,15260
| | - Breanne McDermott
- Department of Neurobiology, University of Pittsburgh, Pittsburgh, PA,15260
| | - Bryan T. Hurtle
- Department of Neurobiology, University of Pittsburgh, Pittsburgh, PA,15260
- Center for Neuroscience, University of Pittsburgh, Pittsburgh, PA,15260
| | - Takashi Saito
- Department of Neurocognitive Science, Institute of Brain Science, Nagoya City University Graduate School of Medical Science, Nagoya, 467-8601, Japan
- Laboratory for Proteolytic Neuroscience, RIKEN Center for Brain Science, Saitama, 351-0198, Japan
| | - Takaomi C. Saido
- Laboratory for Proteolytic Neuroscience, RIKEN Center for Brain Science, Saitama, 351-0198, Japan
| | - Matthew L. MacDonald
- Department of Psychiatry, University of Pittsburgh, Pittsburgh, PA, 15260
- Biomedical Mass Spectrometry Center, University of Pittsburgh, Pittsburgh, PA,15260
| | - Gregg E. Homanics
- Department of Neurobiology, University of Pittsburgh, Pittsburgh, PA,15260
- Department of Anesthesiology & Perioperative Medicine, University of Pittsburgh, Pittsburgh, PA, 15260
- University of Pittsburgh Brain Institute, University of Pittsburgh, Pittsburgh, PA, 15260
- Department of Pharmacology and Chemical Biology, University of Pittsburgh, Pittsburgh, PA, 15260
| | - Amantha Thathiah
- Department of Neurobiology, University of Pittsburgh, Pittsburgh, PA,15260
- University of Pittsburgh Brain Institute, University of Pittsburgh, Pittsburgh, PA, 15260
- Pittsburgh Institute for Neurodegenerative Diseases, University of Pittsburgh, Pittsburgh, PA, 15260
- Center for Protein Conformational Diseases, Kenneth P. Dietrich School of Arts and Sciences, University of Pittsburgh, Pittsburgh, PA,15260
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12
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Rizzo SJS, Homanics GE, Park JE, Silva AC, Strick PL. Establishing the marmoset as a non‐human primate model of Alzheimer’s disease. Alzheimers Dement 2021. [DOI: 10.1002/alz.049952] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
| | | | - Jung Eun Park
- University of Pittsburgh School of Medicine Pittsburgh PA USA
| | - Afonso C Silva
- University of Pittsburgh School of Medicine Pittsburgh PA USA
| | - Peter L Strick
- University of Pittsburgh School of Medicine Pittsburgh PA USA
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13
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Goldberg LR, Yao EJ, Kelliher JC, Reed ER, Cox JW, Parks C, Kirkpatrick SL, Beierle JA, Chen MM, Johnson WE, Homanics GE, Williams RW, Bryant CD, Mulligan MK. A quantitative trait variant in Gabra2 underlies increased methamphetamine stimulant sensitivity. Genes Brain Behav 2021; 20:e12774. [PMID: 34677900 PMCID: PMC9083095 DOI: 10.1111/gbb.12774] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/29/2021] [Revised: 08/19/2021] [Accepted: 09/15/2021] [Indexed: 12/24/2022]
Abstract
Psychostimulant (methamphetamine, cocaine) use disorders have a genetic component that remains mostly unknown. We conducted genome-wide quantitative trait locus (QTL) analysis of methamphetamine stimulant sensitivity. To facilitate gene identification, we employed a Reduced Complexity Cross between closely related C57BL/6 mouse substrains and examined maximum speed and distance traveled over 30 min following methamphetamine (2 mg/kg, i.p.). For maximum methamphetamine-induced speed following the second and third administration, we identified a single genome-wide significant QTL on chromosome 11 that peaked near the Cyfip2 locus (LOD = 3.5, 4.2; peak = 21 cM [36 Mb]). For methamphetamine-induced distance traveled following the first and second administration, we identified a genome-wide significant QTL on chromosome 5 that peaked near a functional intronic indel in Gabra2 coding for the alpha-2 subunit of the GABA-A receptor (LOD = 3.6-5.2; peak = 34-35 cM [66-67 Mb]). Striatal cis-expression QTL mapping corroborated Gabra2 as a functional candidate gene underlying methamphetamine-induced distance traveled. CRISPR/Cas9-mediated correction of the mutant intronic deletion on the C57BL/6J background to the wild-type C57BL/6NJ allele was sufficient to reduce methamphetamine-induced locomotor activity toward the wild-type C57BL/6NJ-like level, thus validating the quantitative trait variant (QTV). These studies show the power and efficiency of Reduced Complexity Crosses in identifying causal variants underlying complex traits. Functionally restoring Gabra2 expression decreased methamphetamine stimulant sensitivity and supports preclinical and human genetic studies implicating the GABA-A receptor in psychostimulant addiction-relevant traits. Importantly, our findings have major implications for studying psychostimulants in the C57BL/6J strain-the gold standard strain in biomedical research.
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Affiliation(s)
- Lisa R. Goldberg
- Laboratory of Addiction Genetics, Department of Pharmacology and Experimental Therapeutics and Psychiatry, Boston, Massachusetts, USA
- NIGMS T32 Ph.D. Training Program in Biomolecular Pharmacology, Boston University School of Medicine, Boston, Massachusetts, USA
| | - Emily J. Yao
- Laboratory of Addiction Genetics, Department of Pharmacology and Experimental Therapeutics and Psychiatry, Boston, Massachusetts, USA
| | - Julia C. Kelliher
- Laboratory of Addiction Genetics, Department of Pharmacology and Experimental Therapeutics and Psychiatry, Boston, Massachusetts, USA
| | - Eric R. Reed
- Ph.D. Program in Bioinformatics, Boston University, Boston, Massachusetts, USA
| | - Jiayi Wu Cox
- Program in Biomedical Sciences, Graduate Program in Genetics and Genomics, Boston University School of Medicine, Boston, Massachusetts, USA
| | - Cory Parks
- Department of Agricultural, Biology, and Health Sciences, Cameron University, Lawton, Oklahoma, USA
| | - Stacey L. Kirkpatrick
- Laboratory of Addiction Genetics, Department of Pharmacology and Experimental Therapeutics and Psychiatry, Boston, Massachusetts, USA
| | - Jacob A. Beierle
- Laboratory of Addiction Genetics, Department of Pharmacology and Experimental Therapeutics and Psychiatry, Boston, Massachusetts, USA
- NIGMS T32 Ph.D. Training Program in Biomolecular Pharmacology, Boston University School of Medicine, Boston, Massachusetts, USA
| | - Melanie M. Chen
- Laboratory of Addiction Genetics, Department of Pharmacology and Experimental Therapeutics and Psychiatry, Boston, Massachusetts, USA
| | - William E. Johnson
- Department of Medicine, Computational Medicine, Boston University School of Medicine, Boston, Massachusetts, USA
| | - Gregg E. Homanics
- Departments of Anesthesiology, Neurobiology, and Pharmacology and Chemical Biology, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
| | - Robert W. Williams
- Department of Genetics, Genomics and Informatics, University of Tennessee Health Science Center, Memphis, Tennessee, USA
| | - Camron D. Bryant
- Laboratory of Addiction Genetics, Department of Pharmacology and Experimental Therapeutics and Psychiatry, Boston, Massachusetts, USA
| | - Megan K. Mulligan
- Department of Genetics, Genomics and Informatics, University of Tennessee Health Science Center, Memphis, Tennessee, USA
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14
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Figueroa AG, Benkwitz C, Surges G, Kunz N, Homanics GE, Pearce RA. Hippocampal β2-GABA A receptors mediate LTP suppression by etomidate and contribute to long-lasting feedback but not feedforward inhibition of pyramidal neurons. J Neurophysiol 2021; 126:1090-1100. [PMID: 34406874 PMCID: PMC8560413 DOI: 10.1152/jn.00303.2021] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The general anesthetic etomidate, which acts through γ-aminobutyric acid type A (GABAA) receptors, impairs the formation of new memories under anesthesia. This study addresses the molecular and cellular mechanisms by which this occurs. Here, using a new line of genetically engineered mice carrying the GABAA receptor (GABAAR) β2-N265M mutation, we tested the roles of receptors that incorporate GABAA receptor β2 versus β3 subunits to suppression of long-term potentiation (LTP), a cellular model of learning and memory. We found that brain slices from β2-N265M mice resisted etomidate suppression of LTP, indicating that the β2-GABAARs are an essential target in this model. As these receptors are most heavily expressed by interneurons in the hippocampus, this finding supports a role for interneuron modulation in etomidate control of synaptic plasticity. Nevertheless, β2 subunits are also expressed by pyramidal neurons, so they might also contribute. Therefore, using a previously established line of β3-N265M mice, we also examined the contributions of β2- versus β3-GABAARs to GABAA,slow dendritic inhibition, because dendritic inhibition is particularly well suited to controlling synaptic plasticity. We also examined their roles in long-lasting suppression of population activity through feedforward and feedback inhibition. We found that both β2- and β3-GABAARs contribute to GABAA,slow inhibition and that both β2- and β3-GABAARs contribute to feedback inhibition, whereas only β3-GABAARs contribute to feedforward inhibition. We conclude that modulation of β2-GABAARs is essential to etomidate suppression of LTP. Furthermore, to the extent that this occurs through GABAARs on pyramidal neurons, it is through modulation of feedback inhibition.NEW & NOTEWORTHY Etomidate exerts its anesthetic actions through GABAA receptors. However, the mechanism remains unknown. Here, using a hippocampal brain slice model, we show that β2-GABAARs are essential to this effect. We also show that these receptors contribute to long-lasting dendritic inhibition in feedback but not feedforward inhibition of pyramidal neurons. These findings hold implications for understanding how anesthetics block memory formation and, more generally, how inhibitory circuits control learning and memory.
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Affiliation(s)
- Alexander G Figueroa
- Department of Anesthesiology, University of Wisconsin-Madison, Madison, Wisconsin
| | - Claudia Benkwitz
- Department of Anesthesiology, University of Wisconsin-Madison, Madison, Wisconsin.,Department of Anesthesiology and Perioperative Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Gabe Surges
- Department of Anesthesiology, University of Wisconsin-Madison, Madison, Wisconsin
| | - Nicholas Kunz
- Department of Anesthesiology and Perioperative Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Gregg E Homanics
- Department of Anesthesiology and Perioperative Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Robert A Pearce
- Department of Anesthesiology, University of Wisconsin-Madison, Madison, Wisconsin
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15
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Grubisha MJ, Sun X, MacDonald ML, Garver M, Sun Z, Paris KA, Patel DS, DeGiosio RA, Lewis DA, Yates NA, Camacho C, Homanics GE, Ding Y, Sweet RA. MAP2 is differentially phosphorylated in schizophrenia, altering its function. Mol Psychiatry 2021; 26:5371-5388. [PMID: 33526823 PMCID: PMC8325721 DOI: 10.1038/s41380-021-01034-z] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/16/2020] [Revised: 01/04/2021] [Accepted: 01/15/2021] [Indexed: 01/30/2023]
Abstract
Schizophrenia (Sz) is a highly polygenic disorder, with common, rare, and structural variants each contributing only a small fraction of overall disease risk. Thus, there is a need to identify downstream points of convergence that can be targeted with therapeutics. Reduction of microtubule-associated protein 2 (MAP2) immunoreactivity (MAP2-IR) is present in individuals with Sz, despite no change in MAP2 protein levels. MAP2 is phosphorylated downstream of multiple receptors and kinases identified as Sz risk genes, altering its immunoreactivity and function. Using an unbiased phosphoproteomics approach, we quantified 18 MAP2 phosphopeptides, 9 of which were significantly altered in Sz subjects. Network analysis grouped MAP2 phosphopeptides into three modules, each with a distinct relationship to dendritic spine loss, synaptic protein levels, and clinical function in Sz subjects. We then investigated the most hyperphosphorylated site in Sz, phosphoserine1782 (pS1782). Computational modeling predicted phosphorylation of S1782 reduces binding of MAP2 to microtubules, which was confirmed experimentally. We generated a transgenic mouse containing a phosphomimetic mutation at S1782 (S1782E) and found reductions in basilar dendritic length and complexity along with reduced spine density. Because only a limited number of MAP2 interacting proteins have been previously identified, we combined co-immunoprecipitation with mass spectrometry to characterize the MAP2 interactome in mouse brain. The MAP2 interactome was enriched for proteins involved in protein translation. These associations were shown to be functional as overexpression of wild type and phosphomimetic MAP2 reduced protein synthesis in vitro. Finally, we found that Sz subjects with low MAP2-IR had reductions in the levels of synaptic proteins relative to nonpsychiatric control (NPC) subjects and to Sz subjects with normal and MAP2-IR, and this same pattern was recapitulated in S1782E mice. These findings suggest a new conceptual framework for Sz-that a large proportion of individuals have a "MAP2opathy"-in which MAP function is altered by phosphorylation, leading to impairments of neuronal structure, synaptic protein synthesis, and function.
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Affiliation(s)
- M J Grubisha
- Department of Psychiatry, Translational Neuroscience Program, School of Medicine, University of Pittsburgh, Pittsburgh, PA, USA
| | - X Sun
- Department of Psychiatry, Translational Neuroscience Program, School of Medicine, University of Pittsburgh, Pittsburgh, PA, USA
- Tsinghua MD Program, School of Medicine, Tsinghua University, Beijing, China
| | - M L MacDonald
- Department of Psychiatry, Translational Neuroscience Program, School of Medicine, University of Pittsburgh, Pittsburgh, PA, USA
| | - M Garver
- Department of Psychiatry, Translational Neuroscience Program, School of Medicine, University of Pittsburgh, Pittsburgh, PA, USA
| | - Z Sun
- Department of Biostatistics, University of Pittsburgh, Pittsburgh, PA, USA
| | - K A Paris
- Department of Computational and Systems Biology, University of Pittsburgh, Pittsburgh, PA, USA
| | - D S Patel
- Department of Computational and Systems Biology, University of Pittsburgh, Pittsburgh, PA, USA
| | - R A DeGiosio
- Department of Psychiatry, Translational Neuroscience Program, School of Medicine, University of Pittsburgh, Pittsburgh, PA, USA
| | - D A Lewis
- Department of Psychiatry, Translational Neuroscience Program, School of Medicine, University of Pittsburgh, Pittsburgh, PA, USA
| | - N A Yates
- Department of Cell Biology, University of Pittsburgh, Pittsburgh, PA, USA
- Biomedical Mass Spectrometry Center, University of Pittsburgh, Pittsburgh, PA, USA
| | - C Camacho
- Department of Computational and Systems Biology, University of Pittsburgh, Pittsburgh, PA, USA
| | - G E Homanics
- Department of Anesthesiology and Perioperative Medicine, School of Medicine, University of Pittsburgh, Pittsburgh, PA, USA
- Department of Pharmacology & Chemical Biology, School of Medicine, University of Pittsburgh, Pittsburgh, PA, USA
- Department of Neurobiology, School of Medicine, University of Pittsburgh, Pittsburgh, PA, USA
| | - Y Ding
- Department of Biostatistics, University of Pittsburgh, Pittsburgh, PA, USA
| | - R A Sweet
- Department of Psychiatry, Translational Neuroscience Program, School of Medicine, University of Pittsburgh, Pittsburgh, PA, USA.
- Department of Neurology, School of Medicine, University of Pittsburgh, Pittsburgh, PA, USA.
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16
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Abstract
The development of CRISPR/Cas9 technology has vastly sped up the process of mammalian genome editing by introducing a bacterial system that can be exploited for reverse genetics-based research. However, generating homozygous functional knockout (KO) animals using traditional CRISPR/Cas9-mediated techniques requires three generations of animals. A founder animal with a desired mutation is crossed to produce heterozygous F1 offspring which are subsequently interbred to generate homozygous F2 KO animals. This study describes an adaptation of the CRISPR/Cas9-mediated method to develop a cohort of homozygous gene-targeted KO animals in one generation. A well-characterized ethanol-responsive gene, MyD88, was chosen as a candidate gene for generation of KO mice as proof-of-concept. Previous studies have reported changes in ethanol-related behavioral outcomes in MyD88 KO mice. One-cell mouse embryos were simultaneously electroporated with four gRNAs targeting a critical Exon of MyD88 along with Cas9 protein. DNA and RNA analysis of founder mice revealed a complex mix of genetic alterations, all of which were predicted to ablate MyD88 gene function. Behavioral testing confirmed the hypothesis that successful one-generation KO of MyD88 would reproduce the decreased ethanol-induced sedative/hypnotic effects and increased ethanol consumption in males that were observed in previous studies. This study additionally compared responses of Mock treatment control mice generated through electroporation to controls purchased from a vendor. No substantial behavioral changes were noted between control cohorts. Overall, the CRISPR/Cas9 KO protocol reported here, which we call CRISPR Turbo Accelerated KnockOut (CRISPy TAKO), will be useful for reverse genetic in vivo screens of gene function in whole animals.
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Affiliation(s)
- Sonja L Plasil
- Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States
| | - Amit Seth
- Department of Anesthesiology and Perioperative Medicine, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States
| | - Gregg E Homanics
- Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States.,Department of Anesthesiology and Perioperative Medicine, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States.,Department of Neurobiology, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States
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17
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Saba LM, Hoffman PL, Homanics GE, Mahaffey S, Daulatabad SV, Janga SC, Tabakoff B. A long non-coding RNA (Lrap) modulates brain gene expression and levels of alcohol consumption in rats. Genes Brain Behav 2020; 20:e12698. [PMID: 32893479 PMCID: PMC7900948 DOI: 10.1111/gbb.12698] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/09/2020] [Revised: 08/20/2020] [Accepted: 09/01/2020] [Indexed: 12/14/2022]
Abstract
LncRNAs are important regulators of quantitative and qualitative features of the transcriptome. We have used QTL and other statistical analyses to identify a gene coexpression module associated with alcohol consumption. The "hub gene" of this module, Lrap (Long non-coding RNA for alcohol preference), was an unannotated transcript resembling a lncRNA. We used partial correlation analyses to establish that Lrap is a major contributor to the integrity of the coexpression module. Using CRISPR/Cas9 technology, we disrupted an exon of Lrap in Wistar rats. Measures of alcohol consumption in wild type, heterozygous and knockout rats showed that disruption of Lrap produced increases in alcohol consumption/alcohol preference. The disruption of Lrap also produced changes in expression of over 700 other transcripts. Furthermore, it became apparent that Lrap may have a function in alternative splicing of the affected transcripts. The GO category of "Response to Ethanol" emerged as one of the top candidates in an enrichment analysis of the differentially expressed transcripts. We validate the role of Lrap as a mediator of alcohol consumption by rats, and also implicate Lrap as a modifier of the expression and splicing of a large number of brain transcripts. A defined subset of these transcripts significantly impacts alcohol consumption by rats (and possibly humans). Our work shows the pleiotropic nature of non-coding elements of the genome, the power of network analysis in identifying the critical elements influencing phenotypes, and the fact that not all changes produced by genetic editing are critical for the concomitant changes in phenotype.
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Affiliation(s)
- Laura M Saba
- Department of Pharmaceutical Sciences, Skaggs School of Pharmacy & Pharmaceutical Sciences, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA
| | - Paula L Hoffman
- Department of Pharmaceutical Sciences, Skaggs School of Pharmacy & Pharmaceutical Sciences, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA.,Department of Pharmacology, School of Medicine, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA
| | - Gregg E Homanics
- Departments of Anesthesiology, Neurobiology and Pharmacology & Chemical Biology, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
| | - Spencer Mahaffey
- Department of Pharmaceutical Sciences, Skaggs School of Pharmacy & Pharmaceutical Sciences, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA
| | - Swapna Vidhur Daulatabad
- Department of BioHealth Informatics, Indiana University School of Informatics and Computing, Indiana University-Purdue University Indianapolis, Indianapolis, Indiana, USA
| | - Sarath Chandra Janga
- Department of BioHealth Informatics, Indiana University School of Informatics and Computing, Indiana University-Purdue University Indianapolis, Indianapolis, Indiana, USA.,Department of Medical and Molecular Genetics, Indiana University School of Medicine, Indianapolis, Indiana, USA.,Center for Computational Biology and Bioinformatics, Indiana University School of Medicine, Indianapolis, Indiana, USA
| | - Boris Tabakoff
- Department of Pharmaceutical Sciences, Skaggs School of Pharmacy & Pharmaceutical Sciences, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA
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18
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Abstract
Substance use disorders are highly prevalent and continue to be one of the leading causes of disability in the world. Notably, not all people who use addictive drugs develop a substance use disorder. Although substance use disorders are highly heritable, patterns of inheritance cannot be explained purely by Mendelian genetic mechanisms. Vulnerability to developing drug addiction depends on the interplay between genetics and environment. Additionally, evidence from the past decade has pointed to the role of epigenetic inheritance in drug addiction. This emerging field focuses on how environmental perturbations, including exposure to addictive drugs, induce epigenetic modifications that are transmitted to the embryo at fertilization and modify developmental gene expression programs to ultimately impact subsequent generations. This chapter highlights intergenerational and transgenerational phenotypes in offspring following a history of parental drug exposure. Special attention is paid to parental preconception exposure studies of five drugs of abuse (alcohol, cocaine, nicotine, cannabinoids, and opiates) and associated behavioral and physiological outcomes in offspring. The highlighted studies demonstrate that parental exposure to drugs of abuse has enduring effects that persist into subsequent generations. Understanding the contribution of epigenetic inheritance in drug addiction may provide clues for better treatments and therapies for substance use disorders.
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Affiliation(s)
- Annalisa M Baratta
- Center for Neuroscience, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States
| | - Richa S Rathod
- Department of Anesthesiology and Perioperative Medicine, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States
| | - Sonja L Plasil
- Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States
| | - Amit Seth
- Department of Anesthesiology and Perioperative Medicine, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States
| | - Gregg E Homanics
- Center for Neuroscience, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States; Department of Anesthesiology and Perioperative Medicine, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States; Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States; Department of Neurobiology, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States.
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19
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Rathod RS, Ferguson C, Seth A, Baratta AM, Plasil SL, Homanics GE. Effects of Paternal Preconception Vapor Alcohol Exposure Paradigms on Behavioral Responses in Offspring. Brain Sci 2020; 10:brainsci10090658. [PMID: 32971974 PMCID: PMC7564629 DOI: 10.3390/brainsci10090658] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2020] [Revised: 09/16/2020] [Accepted: 09/18/2020] [Indexed: 12/26/2022] Open
Abstract
We and others previously reported that paternal preconception chronic ethanol exposure leads to molecular, physiological, and behavioral changes in offspring including reduced ethanol consumption and preference relative to controls. The goal of the present study was to further explore the impact of paternal ethanol exposure on a wide variety of basal and drug-induced behavioral responses in first generation offspring. Adult male mice were exposed to chronic intermittent vapor ethanol or control conditions for 5-6 weeks before being mated with ethanol-naïve females to produce ethanol (E)- and control (C)-sired offspring. E-sired male offspring showed stress hyporesponsivity in a stress-induced hyperthermia assay and E-sired female offspring had reduced binge-like ethanol consumption in a drinking in the dark assay compared to C-sired offspring. E-sired offspring also showed altered sensitivity to a sedative/hypnotic dose of the GABAergic drug midazolam, but not ketamine or ethanol, in a loss of the righting response assay. E-sired offspring did not differ from controls in marble burying, novel object location, novel object recognition, social interaction, bottle-brush, novelty suppressed feeding, prepulse inhibition, every-other-day ethanol drinking, or home cage activity assays. This study adds to a growing body of literature suggesting that like in utero alcohol exposure, paternal preconception alcohol exposure can also have effects that persist and impact behavior of offspring.
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Affiliation(s)
- Richa S. Rathod
- Department of Anesthesiology & Perioperative Medicine, University of Pittsburgh School of Medicine, Pittsburgh, PA 15261, USA; (R.S.R.); (C.F.); (A.S.)
| | - Carolyn Ferguson
- Department of Anesthesiology & Perioperative Medicine, University of Pittsburgh School of Medicine, Pittsburgh, PA 15261, USA; (R.S.R.); (C.F.); (A.S.)
| | - Amit Seth
- Department of Anesthesiology & Perioperative Medicine, University of Pittsburgh School of Medicine, Pittsburgh, PA 15261, USA; (R.S.R.); (C.F.); (A.S.)
| | - Annalisa M. Baratta
- Center for Neuroscience, University of Pittsburgh School of Medicine, Pittsburgh, PA 15261, USA;
| | - Sonja L. Plasil
- Department of Pharmacology & Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15261, USA;
| | - Gregg E. Homanics
- Department of Anesthesiology & Perioperative Medicine, University of Pittsburgh School of Medicine, Pittsburgh, PA 15261, USA; (R.S.R.); (C.F.); (A.S.)
- Center for Neuroscience, University of Pittsburgh School of Medicine, Pittsburgh, PA 15261, USA;
- Department of Pharmacology & Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15261, USA;
- Department of Neurobiology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15261, USA
- Correspondence: ; Tel.: +1-412-648-8172
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20
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Rompala GR, Ferguson C, Homanics GE. Coincubation of sperm with epididymal extracellular vesicle preparations from chronic intermittent ethanol-treated mice is sufficient to impart anxiety-like and ethanol-induced behaviors to adult progeny. Alcohol 2020; 87:111-120. [PMID: 32445808 PMCID: PMC7484209 DOI: 10.1016/j.alcohol.2020.05.001] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2020] [Revised: 05/11/2020] [Accepted: 05/15/2020] [Indexed: 12/17/2022]
Abstract
We previously reported that paternal preconception chronic ethanol exposure in mice imparts adult male offspring with reduced ethanol drinking preference and consumption, increased ethanol sensitivity, and attenuated stress responsivity. That same chronic ethanol exposure paradigm was later revealed to affect the sperm epigenome by altering the abundance of several small noncoding RNAs, a mechanism that mediates the intergenerational effects of numerous paternal environmental exposures. Although recent studies have revealed that the unique RNA signature of sperm is shaped during maturation in the epididymis via extracellular vesicles (EVs), formal demonstration that EVs mediate the effects of paternal preconception perturbations is lacking. Therefore, in the current study we tested the hypothesis that epididymal EV preparations are sufficient to induce intergenerational effects of paternal preconception ethanol exposure on offspring. To test this hypothesis, sperm from ethanol-naïve donors were incubated with epididymal EV preparations from chronic ethanol (Ethanol EV-donor) or control-treated (Control EV-donor) mice prior to in vitro fertilization (IVF) and embryo transfer. Progeny were examined for ethanol- and stress-related behaviors in adulthood. Ethanol EV-donors imparted reduced body weight at weaning and imparted modestly increased limited access ethanol intake to male offspring. Ethanol-EV donors also imparted increased basal anxiety-like behavior and reduced sensitivity to ethanol-induced anxiolysis to female offspring. Although Ethanol EV-donor treatment did not recapitulate the ethanol- or stress-related intergenerational effects of paternal ethanol following natural mating, these results demonstrate that coincubation of sperm with epididymal EV preparations is sufficient to impart intergenerational effects of ethanol through the male germline. This mechanism may generalize to the intergenerational effects of a wide variety of paternal preconception perturbations.
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21
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Muñoz B, Gallegos S, Peters C, Murath P, Lovinger DM, Homanics GE, Aguayo LG. Influence of nonsynaptic α1 glycine receptors on ethanol consumption and place preference. Addict Biol 2020; 25:e12726. [PMID: 30884072 DOI: 10.1111/adb.12726] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2018] [Revised: 11/23/2018] [Accepted: 01/17/2019] [Indexed: 12/21/2022]
Abstract
Here, we used knock-in (KI) mice that have ethanol-insensitive alpha 1 glycine receptors (GlyRs) (KK385/386AA) to examine how alpha 1 GlyRs might affect binge drinking and conditioned place preference. Data show that tonic alpha 1 GlyR-mediated currents were exclusively sensitive to ethanol only in wild-type mice. Behavioral studies showed that the KI mice have a higher intake of ethanol upon first exposure to drinking and greater conditioned place preference to ethanol. This study suggests that nonsynaptic alpha 1-containing GlyRs have a role in motivational and early reinforcing effects of ethanol.
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Affiliation(s)
- Braulio Muñoz
- Laboratory of Neurophysiology, Department of PhysiologyUniversidad de Concepcion Concepcion Chile
| | - Scarlet Gallegos
- Laboratory of Neurophysiology, Department of PhysiologyUniversidad de Concepcion Concepcion Chile
| | - Christian Peters
- Laboratory of Neurophysiology, Department of PhysiologyUniversidad de Concepcion Concepcion Chile
| | - Pablo Murath
- Laboratory of Neurophysiology, Department of PhysiologyUniversidad de Concepcion Concepcion Chile
| | - David M. Lovinger
- Laboratory for Integrative Neuroscience, National Institute on Alcohol Abuse and AlcoholismNational Institutes of Health Bethesda Maryland USA
| | - Gregg E. Homanics
- Department of AnesthesiologyUniversity of Pittsburgh Pittsburgh Pennsylvania USA
- Department Pharmacology and Chemical BiologyUniversity of Pittsburgh Pittsburgh Pennsylvania USA
| | - Luis G. Aguayo
- Laboratory of Neurophysiology, Department of PhysiologyUniversidad de Concepcion Concepcion Chile
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22
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Zamudio PA, Smothers TC, Homanics GE, Woodward JJ. Knock-in Mice Expressing an Ethanol-Resistant GluN2A NMDA Receptor Subunit Show Altered Responses to Ethanol. Alcohol Clin Exp Res 2020; 44:479-491. [PMID: 31872888 PMCID: PMC7018579 DOI: 10.1111/acer.14273] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2019] [Accepted: 12/16/2019] [Indexed: 12/19/2022]
Abstract
BACKGROUND N-methyl-D-aspartate receptors (NMDARs) are glutamate-activated, heterotetrameric ligand-gated ion channels critically important in virtually all aspects of glutamatergic signaling. Ethanol (EtOH) inhibition of NMDARs is thought to mediate specific actions of EtOH during acute and chronic exposure. Studies from our laboratory, and others, identified EtOH-sensitive sites within specific transmembrane (TM) domains involved in channel gating as well as those in subdomains of extracellular and intracellular regions of GluN1 and GluN2 subunits that affect channel function. In this study, we characterize for the first time the physiological and behavioral effects of EtOH on knock-in mice expressing a GluN2A subunit that shows reduced sensitivity to EtOH. METHODS A battery of tests evaluating locomotion, anxiety, sedation, motor coordination, and voluntary alcohol intake were performed in wild-type mice and those expressing the GluN2A A825W knock-in mutation. Whole-cell patch-clamp electrophysiological recordings were used to confirm reduced EtOH sensitivity of NMDAR-mediated currents in 2 separate brain regions (mPFC and the cerebellum) where the GluN2A subunit is known to contribute to NMDAR-mediated responses. RESULTS Male and female mice homozygous for the GluN2A(A825W) knock-in mutation showed reduced EtOH inhibition of NMDAR-mediated synaptic currents in mPFC and cerebellar neurons as compared to their wild-type counterparts. GluN2A(A825W) male but not female mice were less sensitive to the sedative and motor-incoordinating effects of EtOH and showed a rightward shift in locomotor-stimulating effects of EtOH. There was no effect of the mutation on EtOH-induced anxiolysis or voluntary EtOH consumption in either male or female mice. CONCLUSIONS These findings show that expression of EtOH-resistant GluN2A NMDARs results in selective and sex-specific changes in the behavioral sensitivity to EtOH.
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Affiliation(s)
- Paula A Zamudio
- Department of Neuroscience, Medical University of South Carolina, Charleston, South Carolina
| | - Thetford C Smothers
- Department of Neuroscience, Medical University of South Carolina, Charleston, South Carolina
| | - Gregg E Homanics
- Department of Anesthesiology and Perioperative Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - John J Woodward
- Department of Neuroscience, Medical University of South Carolina, Charleston, South Carolina
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23
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Rompala GR, Homanics GE. Intergenerational Effects of Alcohol: A Review of Paternal Preconception Ethanol Exposure Studies and Epigenetic Mechanisms in the Male Germline. Alcohol Clin Exp Res 2019; 43:1032-1045. [PMID: 30908630 PMCID: PMC6551262 DOI: 10.1111/acer.14029] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2018] [Accepted: 03/13/2019] [Indexed: 12/11/2022]
Abstract
While alcohol use disorder (AUD) is a highly heritable psychiatric disease, efforts to elucidate that heritability by examining genetic variation (e.g., single nucleotide polymorphisms) have been insufficient to fully account for familial AUD risk. Perhaps not coincidently, there has been a burgeoning interest in novel nongenomic mechanisms of inheritance (i.e., epigenetics) that are shaped in the male or female germ cells by significant lifetime experiences such as exposure to chronic stress, malnutrition, or drugs of abuse. While many epidemiological and preclinical studies have long pointed to a role for the parental preconception environment in offspring behavior, over the last decade many studies have implicated a causal relationship between the environmentally sensitive sperm epigenome and intergenerational phenotypes. This critical review will detail the heritable effects of alcohol and the potential role for epigenetics.
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Affiliation(s)
- Gregory R Rompala
- Center for Neuroscience, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
| | - Gregg E Homanics
- Center for Neuroscience, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
- Department of Pharmacology & Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
- Department of Anesthesiology and Perioperative Medicine, University of Pittsburgh School Medicine, Pittsburgh, Pennsylvania
- Department of Neurobiology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
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24
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Harmon DB, Mandler WK, Sipula IJ, Dedousis N, Lewis SE, Eckels JT, Du J, Wang Y, Huckestein BR, Pagano PJ, Cifuentes-Pagano E, Homanics GE, Van't Erve TJ, Stefanovic-Racic M, Jurczak MJ, O'Doherty RM, Kelley EE. Hepatocyte-Specific Ablation or Whole-Body Inhibition of Xanthine Oxidoreductase in Mice Corrects Obesity-Induced Systemic Hyperuricemia Without Improving Metabolic Abnormalities. Diabetes 2019; 68:1221-1229. [PMID: 30936145 PMCID: PMC6610025 DOI: 10.2337/db18-1198] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/07/2018] [Accepted: 03/18/2019] [Indexed: 01/20/2023]
Abstract
Systemic hyperuricemia (HyUA) in obesity/type 2 diabetes facilitated by elevated activity of xanthine oxidoreductase (XOR), which is the sole source of uric acid (UA) in mammals, has been proposed to contribute to the pathogenesis of insulin resistance/dyslipidemia in obesity. Here, the effects of hepatocyte-specific ablation of Xdh, the gene encoding XOR (HXO), and whole-body pharmacologic inhibition of XOR (febuxostat) on obesity-induced insulin resistance/dyslipidemia were assessed. Deletion of hepatocyte Xdh substantially lowered liver and plasma UA concentration. When exposed to an obesogenic diet, HXO and control floxed (FLX) mice became equally obese, but systemic HyUA was absent in HXO mice. Despite this, obese HXO mice became as insulin resistant and dyslipidemic as obese FLX mice. Similarly, febuxostat dramatically lowered plasma and tissue UA and XOR activity in obese wild-type mice without altering obesity-associated insulin resistance/dyslipidemia. These data demonstrate that hepatocyte XOR activity is a critical determinant of systemic UA homeostasis, that deletion of hepatocyte Xdh is sufficient to prevent systemic HyUA of obesity, and that neither prevention nor correction of HyUA improves insulin resistance/dyslipidemia in obesity. Thus, systemic HyUA, although clearly a biomarker of the metabolic abnormalities of obesity, does not appear to be causative.
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Affiliation(s)
- Daniel B Harmon
- Division of Endocrinology and Metabolism, Department of Medicine, University of Pittsburgh, Pittsburgh, PA
- Center for Metabolism and Mitochondrial Medicine, University of Pittsburgh, Pittsburgh, PA
| | - W Kyle Mandler
- Department of Physiology and Pharmacology, Health Sciences Center, West Virginia University, Morgantown, WV
| | - Ian J Sipula
- Division of Endocrinology and Metabolism, Department of Medicine, University of Pittsburgh, Pittsburgh, PA
- Center for Metabolism and Mitochondrial Medicine, University of Pittsburgh, Pittsburgh, PA
| | - Nikolaos Dedousis
- Division of Endocrinology and Metabolism, Department of Medicine, University of Pittsburgh, Pittsburgh, PA
- Center for Metabolism and Mitochondrial Medicine, University of Pittsburgh, Pittsburgh, PA
| | - Sara E Lewis
- Department of Physiology and Pharmacology, Health Sciences Center, West Virginia University, Morgantown, WV
| | - Jeremy T Eckels
- Department of Physiology and Pharmacology, Health Sciences Center, West Virginia University, Morgantown, WV
| | - Jianhai Du
- Department of Ophthalmology and Biochemistry, Health Sciences Center, West Virginia University, Morgantown, WV
| | - Yekai Wang
- Department of Ophthalmology and Biochemistry, Health Sciences Center, West Virginia University, Morgantown, WV
| | - Brydie R Huckestein
- Division of Endocrinology and Metabolism, Department of Medicine, University of Pittsburgh, Pittsburgh, PA
- Center for Metabolism and Mitochondrial Medicine, University of Pittsburgh, Pittsburgh, PA
| | - Patrick J Pagano
- Pittsburgh Heart, Lung, Blood, and Vascular Medicine Institute and Department of Pharmacology and Chemical Biology, University of Pittsburgh, Pittsburgh, PA
| | - Eugenia Cifuentes-Pagano
- Pittsburgh Heart, Lung, Blood, and Vascular Medicine Institute and Department of Pharmacology and Chemical Biology, University of Pittsburgh, Pittsburgh, PA
| | - Gregg E Homanics
- Pittsburgh Heart, Lung, Blood, and Vascular Medicine Institute and Department of Pharmacology and Chemical Biology, University of Pittsburgh, Pittsburgh, PA
- Department of Anesthesiology and Perioperative Medicine, University of Pittsburgh, Pittsburgh, PA
| | - Thomas J Van't Erve
- Immunity, Inflammation, and Disease Laboratory/Free Radical Metabolism Group, National Institute of Environmental Health Sciences, Research Triangle Park, NC
| | - Maja Stefanovic-Racic
- Division of Endocrinology and Metabolism, Department of Medicine, University of Pittsburgh, Pittsburgh, PA
- Center for Metabolism and Mitochondrial Medicine, University of Pittsburgh, Pittsburgh, PA
| | - Michael J Jurczak
- Division of Endocrinology and Metabolism, Department of Medicine, University of Pittsburgh, Pittsburgh, PA
- Center for Metabolism and Mitochondrial Medicine, University of Pittsburgh, Pittsburgh, PA
| | - Robert M O'Doherty
- Division of Endocrinology and Metabolism, Department of Medicine, University of Pittsburgh, Pittsburgh, PA
- Center for Metabolism and Mitochondrial Medicine, University of Pittsburgh, Pittsburgh, PA
| | - Eric E Kelley
- Department of Physiology and Pharmacology, Health Sciences Center, West Virginia University, Morgantown, WV
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25
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Mulligan MK, Abreo T, Neuner SM, Parks C, Watkins CE, Houseal MT, Shapaker TM, Hook M, Tan H, Wang X, Ingels J, Peng J, Lu L, Kaczorowski CC, Bryant CD, Homanics GE, Williams RW. Identification of a Functional Non-coding Variant in the GABA A Receptor α2 Subunit of the C57BL/6J Mouse Reference Genome: Major Implications for Neuroscience Research. Front Genet 2019; 10:188. [PMID: 30984232 PMCID: PMC6449455 DOI: 10.3389/fgene.2019.00188] [Citation(s) in RCA: 46] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2019] [Accepted: 02/21/2019] [Indexed: 12/16/2022] Open
Abstract
GABA type-A (GABA-A) receptors containing the α2 subunit (GABRA2) are expressed in most brain regions and are critical in modulating inhibitory synaptic function. Genetic variation at the GABRA2 locus has been implicated in epilepsy, affective and psychiatric disorders, alcoholism and drug abuse. Gabra2 expression varies as a function of genotype and is modulated by sequence variants in several brain structures and populations, including F2 crosses originating from C57BL/6J (B6J) and the BXD recombinant inbred family derived from B6J and DBA/2J. Here we demonstrate a global reduction of GABRA2 brain protein and mRNA in the B6J strain relative to other inbred strains, and identify and validate the causal mutation in B6J. The mutation is a single base pair deletion located in an intron adjacent to a splice acceptor site that only occurs in the B6J reference genome. The deletion became fixed in B6J between 1976 and 1991 and is now pervasive in many engineered lines, BXD strains generated after 1991, the Collaborative Cross, and the majority of consomic lines. Repair of the deletion using CRISPR-Cas9-mediated gene editing on a B6J genetic background completely restored brain levels of GABRA2 protein and mRNA. Comparison of transcript expression in hippocampus, cortex, and striatum between B6J and repaired genotypes revealed alterations in GABA-A receptor subunit expression, especially in striatum. These results suggest that naturally occurring variation in GABRA2 levels between B6J and other substrains or inbred strains may also explain strain differences in anxiety-like or alcohol and drug response traits related to striatal function. Characterization of the B6J private mutation in the Gabra2 gene is of critical importance to molecular genetic studies in neurobiological research because this strain is widely used to generate genetically engineered mice and murine genetic populations, and is the most widely utilized strain for evaluation of anxiety-like, depression-like, pain, epilepsy, and drug response traits that may be partly modulated by GABRA2 function.
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Affiliation(s)
- Megan K Mulligan
- Department of Genetics, Genomics and Informatics, University of Tennessee Health Science Center, Memphis, TN, United States
| | - Timothy Abreo
- Department of Genetics, Genomics and Informatics, University of Tennessee Health Science Center, Memphis, TN, United States
| | - Sarah M Neuner
- Department of Anatomy and Neurobiology, University of Tennessee Health Science Center, Memphis, TN, United States.,The Jackson Laboratory, Bar Harbor, ME, United States
| | - Cory Parks
- Department of Genetics, Genomics and Informatics, University of Tennessee Health Science Center, Memphis, TN, United States
| | - Christine E Watkins
- Department of Genetics, Genomics and Informatics, University of Tennessee Health Science Center, Memphis, TN, United States
| | - M Trevor Houseal
- Department of Genetics, Genomics and Informatics, University of Tennessee Health Science Center, Memphis, TN, United States
| | - Thomas M Shapaker
- Department of Genetics, Genomics and Informatics, University of Tennessee Health Science Center, Memphis, TN, United States
| | - Michael Hook
- Department of Genetics, Genomics and Informatics, University of Tennessee Health Science Center, Memphis, TN, United States
| | - Haiyan Tan
- Departments of Structural Biology and Developmental Neurobiology, Center for Proteomics and Metabolomics, St. Jude Children's Research Hospital, Memphis, TN, United States
| | - Xusheng Wang
- Departments of Structural Biology and Developmental Neurobiology, Center for Proteomics and Metabolomics, St. Jude Children's Research Hospital, Memphis, TN, United States
| | - Jesse Ingels
- Department of Genetics, Genomics and Informatics, University of Tennessee Health Science Center, Memphis, TN, United States
| | - Junmin Peng
- Departments of Structural Biology and Developmental Neurobiology, Center for Proteomics and Metabolomics, St. Jude Children's Research Hospital, Memphis, TN, United States
| | - Lu Lu
- Department of Genetics, Genomics and Informatics, University of Tennessee Health Science Center, Memphis, TN, United States
| | | | - Camron D Bryant
- Laboratory of Addiction Genetics, Department of Pharmacology and Experimental Therapeutics and Psychiatry, Boston University School of Medicine, Boston, MA, United States
| | - Gregg E Homanics
- Departments of Anesthesiology and Perioperative Medicine, Neurobiology, and Pharmacology and Chemical Biology, University of Pittsburgh, Pittsburgh, PA, United States
| | - Robert W Williams
- Department of Genetics, Genomics and Informatics, University of Tennessee Health Science Center, Memphis, TN, United States
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26
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Beeler E, Nobile ZL, Homanics GE. Paternal Preconception Every-Other-Day Ethanol Drinking Alters Behavior and Ethanol Consumption in Offspring. Brain Sci 2019; 9:brainsci9030056. [PMID: 30845665 PMCID: PMC6468863 DOI: 10.3390/brainsci9030056] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2019] [Revised: 02/28/2019] [Accepted: 03/04/2019] [Indexed: 01/12/2023] Open
Abstract
Alcohol use disorder is a devastating disease with a complex etiology. Recent preclinical studies have revealed that paternal preconception chronic intermittent ethanol (EtOH) exposure via vaporized EtOH altered drinking behaviors and sensitivity to EtOH selectively in male offspring. In the current study, we used a voluntary oral route of paternal preconception EtOH exposure, i.e., intermittent every-other-day two-bottle choice drinking, and tested offspring for behavioral alterations. Fifteen EtOH drinking sires and 10 control sires were mated to EtOH naïve females to produce EtOH-sired and control-sired offspring. These offspring were tested using the elevated plus maze, open field, drinking in the dark, and unlimited access two-bottle choice assays. We found that paternal preconception every-other-day two-bottle choice drinking resulted in reduced EtOH consumption selectively in male offspring in the drinking in the dark assay compared to control-sired offspring. No differences were detected in either sex in the unlimited access two-bottle choice and elevated plus maze assays. Open field analysis revealed complex changes in basal behavior and EtOH-induced behaviors that were sex specific. We concluded that paternal preconception voluntary EtOH consumption has persistent effects that impact the next generation. This study adds to a growing appreciation that one’s behavioral response to EtOH and EtOH drinking behavior are impacted by EtOH exposure of the prior generation.
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Affiliation(s)
- Erik Beeler
- Department of Anesthesiology and Perioperative Medicine, University of Pittsburgh School of Medicine, 6068 Biomedical Science Tower-3, 3501 Fifth Avenue, Pittsburgh, PA 15261, USA.
| | - Zachary L Nobile
- Department of Biological Sciences, University of Pittsburgh, 4249 Fifth Avenue, Pittsburgh, PA 15260, USA.
| | - Gregg E Homanics
- Department of Anesthesiology and Perioperative Medicine, University of Pittsburgh School of Medicine, 6068 Biomedical Science Tower-3, 3501 Fifth Avenue, Pittsburgh, PA 15261, USA.
- Center for Neuroscience, University of Pittsburgh School of Medicine, 6060 Biomedical Science Tower-3, 3501 Fifth Avenue, Pittsburgh, PA 15261, USA.
- Department of Pharmacology & Chemical Biology, University of Pittsburgh School of Medicine, 6060 Biomedical Science Tower-3, 3501 Fifth Avenue, Pittsburgh, PA 15261, USA.
- Department of Neurobiology, University of Pittsburgh School of Medicine, 6060 Biomedical Science Tower-3, 3501 Fifth Avenue, Pittsburgh, PA 15261, USA.
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27
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Blednov YA, Bajo M, Roberts AJ, Da Costa AJ, Black M, Edmunds S, Mayfield J, Roberto M, Homanics GE, Lasek AW, Hitzemann RJ, Harris RA. Scn4b regulates the hypnotic effects of ethanol and other sedative drugs. Genes Brain Behav 2019; 18:e12562. [PMID: 30817077 PMCID: PMC6612599 DOI: 10.1111/gbb.12562] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/25/2018] [Revised: 02/23/2019] [Accepted: 02/27/2019] [Indexed: 11/28/2022]
Abstract
The voltage-gated sodium channel subunit β4 (SCN4B) regulates neuronal activity by modulating channel gating and has been implicated in ethanol consumption in rodent models and human alcoholics. However, the functional role for Scn4b in ethanol-mediated behaviors is unknown. We determined if genetic global knockout (KO) or targeted knockdown of Scn4b in the central nucleus of the amygdala (CeA) altered ethanol drinking or related behaviors. We used four different ethanol consumption procedures (continuous and intermittent two-bottle choice (2BC), drinking-in-the dark and chronic intermittent ethanol vapor) and found that male and female Scn4b KO mice did not differ from their wild-type (WT) littermates in ethanol consumption in any of the tests. Knockdown of Scn4b mRNA in the CeA also did not alter 2BC ethanol drinking. However, Scn4b KO mice showed longer duration of the loss of righting reflex induced by ethanol, gaboxadol, pentobarbital and ketamine. KO mice showed slower recovery to basal levels of handling-induced convulsions after ethanol injection, which is consistent with the increased sedative effects observed in these mice. However, Scn4b KO mice did not differ in the severity of acute ethanol withdrawal. Acoustic startle responses, ethanol-induced hypothermia and clearance of blood ethanol also did not differ between the genotypes. There were also no functional differences in the membrane properties or excitability of CeA neurons from Scn4b KO and WT mice. Although we found no evidence that Scn4b regulates ethanol consumption in mice, it was involved in the acute hypnotic effects of ethanol and other sedatives.
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Affiliation(s)
- Yuri A Blednov
- Waggoner Center for Alcohol and Addiction Research, The University of Texas at Austin, Austin, Texas
| | - Michal Bajo
- Department of Neuroscience, The Scripps Research Institute, La Jolla, California
| | - Amanda J Roberts
- Department of Neuroscience, The Scripps Research Institute, La Jolla, California
| | - Adriana J Da Costa
- Waggoner Center for Alcohol and Addiction Research, The University of Texas at Austin, Austin, Texas
| | - Mendy Black
- Waggoner Center for Alcohol and Addiction Research, The University of Texas at Austin, Austin, Texas
| | - Stephanie Edmunds
- Department of Behavioral Neuroscience, Oregon Health & Science University, Oregon, Portland
| | - Jody Mayfield
- Waggoner Center for Alcohol and Addiction Research, The University of Texas at Austin, Austin, Texas
| | - Marisa Roberto
- Department of Neuroscience, The Scripps Research Institute, La Jolla, California
| | - Gregg E Homanics
- Department of Anesthesiology & Perioperative Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania.,Department of Neurobiology, University of Pittsburgh, Pittsburgh, Pennsylvania.,Department of Pharmacology & Chemical Biology, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Amy W Lasek
- Department of Psychiatry, University of Illinois at Chicago, Chicago, Illinois
| | - Robert J Hitzemann
- Department of Behavioral Neuroscience, Oregon Health & Science University, Oregon, Portland
| | - Robert A Harris
- Waggoner Center for Alcohol and Addiction Research, The University of Texas at Austin, Austin, Texas
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28
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Varodayan FP, Khom S, Patel RR, Steinman MQ, Hedges DM, Oleata CS, Homanics GE, Roberto M, Bajo M. Role of TLR4 in the Modulation of Central Amygdala GABA Transmission by CRF Following Restraint Stress. Alcohol Alcohol 2019; 53:642-649. [PMID: 29309503 PMCID: PMC6203127 DOI: 10.1093/alcalc/agx114] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2017] [Accepted: 12/08/2017] [Indexed: 12/20/2022] Open
Abstract
Aims Stress induces neuroimmune responses via Toll-like receptor 4 (TLR4) activation. Here, we investigated the role of TLR4 in the effects of the stress peptide corticotropin-releasing factor (CRF) on GABAergic transmission in the central nucleus of the amygdala (CeA) following restraint stress. Methods Tlr4 knock out (KO) and wild-type rats were exposed to no stress (naïve), a single restraint stress (1 h) or repeated restraint stress (1 h per day for 3 consecutive days). After 1 h recovery from the final stress session, whole-cell patch-clamp electrophysiology was used to investigate the effects of CRF (200 nM) on CeA GABAA-mediated spontaneous inhibitory postsynaptic currents (sIPSCs). Results TLR4 does not regulate baseline GABAergic transmission in the CeA of naive and stress-treated animals. However, CRF significantly increased the mean sIPSC frequencies (indicating enhanced GABA release) across all genotypes and stress treatments, except for the Tlr4 KO rats that experienced repeated restraint stress. Conclusions Overall, our results suggest a limited role for TLR4 in CRF's modulation of CeA GABAergic synapses in naïve and single stress rats, though TLR4-deficient rats that experienced repeated psychological stress exhibit a blunted CRF cellular response. Short Summary TLR4 has a limited role in CRF's activation of the CeA under basal conditions, but interacts with the CRF system to regulate GABAergic synapse function in animals that experience repeated psychological stress.
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Affiliation(s)
- F P Varodayan
- Department of Neuroscience, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA, USA
| | - S Khom
- Department of Neuroscience, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA, USA
| | - R R Patel
- Department of Neuroscience, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA, USA
| | - M Q Steinman
- Department of Neuroscience, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA, USA
| | - D M Hedges
- Department of Neuroscience, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA, USA
| | - C S Oleata
- Department of Neuroscience, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA, USA
| | - G E Homanics
- Departments of Anesthesiology, Pharmacology & Chemical Biology, and Neurobiology, University of 6060 Biomedical Science Tower 3, Pittsburgh, Pittsburgh, PA, USA
| | - M Roberto
- Department of Neuroscience, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA, USA
| | - M Bajo
- Department of Neuroscience, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA, USA
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Abstract
Genetically engineered animals are powerful tools that have provided invaluable insights into mechanisms of alcohol action and alcohol-use disorder. Traditionally, production of gene-targeted animals was a tremendously expensive, time consuming, and technically demanding undertaking. However, the recent advent of facile methods for editing the genome at very high efficiency is revolutionizing how these animals are made. While pioneering approaches to create gene-edited animals first used zinc finger nucleases and subsequently used transcription activator-like effector nucleases, these approaches have been largely supplanted in an extremely short period of time with the recent discovery and precocious maturation of the Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR) system. CRISPR uses a short RNA sequence to guide a non-specific CRISPR-associated nuclease (Cas) to a precise, single location in the genome. Because the CRISPR/Cas system can be cheaply, rapidly, and easily reprogrammed to target nearly any genomic locus of interest simply by recoding the sequence of the guide RNA, this gene-editing system has been rapidly adopted by numerous labs around the world. With CRISPR/Cas, it is now possible to perform gene editing directly in early embryos from every species of animals that is of interest to the alcohol field. Techniques have been developed that enable the rapid production of animals in which a gene has been inactivated (knockout) or modified to harbor specific nucleotide changes (knockins). This system has also been used to insert specific DNA sequences such as reporter or recombinase genes into specific loci of interest. Genetically engineered animals created with the CRISPR/Cas system (CRISPy Critters) are being produced at an astounding pace. Animal production is no longer a significant bottleneck to new discoveries. CRISPy animal studies are just beginning to appear in the alcohol literature, but their use is expected to explode in the near future. CRISPy mice, rats, and other model organisms are sure to facilitate advances in our understanding of alcohol-use disorder.
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Affiliation(s)
- Gregg E Homanics
- Department of Anesthesiology, University of Pittsburgh School of Medicine, 6060 Biomedical Science Tower-3, 3501 Fifth Avenue, Pittsburgh, PA 15261, United States; Department of Pharmacology & Chemical Biology, University of Pittsburgh School of Medicine, 6060 Biomedical Science Tower-3, 3501 Fifth Avenue, Pittsburgh, PA 15261, United States; Department of Neurobiology, University of Pittsburgh School of Medicine, 6060 Biomedical Science Tower-3, 3501 Fifth Avenue, Pittsburgh, PA 15261, United States.
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Rompala GR, Simons A, Kihle B, Homanics GE. Paternal Preconception Chronic Variable Stress Confers Attenuated Ethanol Drinking Behavior Selectively to Male Offspring in a Pre-Stress Environment Dependent Manner. Front Behav Neurosci 2018; 12:257. [PMID: 30450042 PMCID: PMC6225737 DOI: 10.3389/fnbeh.2018.00257] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2018] [Accepted: 10/12/2018] [Indexed: 01/08/2023] Open
Abstract
Stress-related psychiatric disorders such as major depression are strongly associated with alcohol abuse and alcohol use disorder. Recently, many epidemiological and preclinical studies suggest that chronic stress prior to conception has cross-generational effects on the behavior and physiological response to stress in subsequent generations. Thus, we hypothesized that chronic stress may also affect ethanol drinking behaviors in the next generation. In the first cohort of mice, we found that paternal preconception chronic variable stress significantly reduced both two-bottle choice and binge-like ethanol drinking selectively in male offspring. However, these results were not replicated in a second cohort that were tested under experimental conditions that were nearly identical, except for one notable difference. Cohort 1 offspring were derived from in-house C57BL/6J sires that were born in the animal vivarium at the University of Pittsburgh whereas cohort 2 offspring were derived from C57BL/6J sires shipped directly from the vendor. Therefore, a third cohort that included both in-house and vendor born sires was analyzed. Consistent with the first two cohorts, we observed a significant interaction between chronic stress and sire-source with only stressed sires that were born in-house able to impart reduced ethanol drinking behaviors to male offspring. Overall, these results demonstrate that paternal preconception stress can impact ethanol drinking behavior in males of the next generation. These studies provide additional support for a recently recognized role of the paternal preconception environment in shaping ethanol drinking behavior.
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Affiliation(s)
- Gregory R Rompala
- Center for Neuroscience, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States
| | - Alison Simons
- Department of Neuroscience, University of Pittsburgh, Pittsburgh, PA, United States
| | - Brooke Kihle
- Department of Neuroscience, University of Pittsburgh, Pittsburgh, PA, United States
| | - Gregg E Homanics
- Center for Neuroscience, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States.,Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States.,Department of Anesthesiology, University of Pittsburgh School Medicine, Pittsburgh, PA, United States.,Department of Neurobiology, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States
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Zamudio-Bulcock PA, Homanics GE, Woodward JJ. Loss of Ethanol Inhibition of N-Methyl-D-Aspartate Receptor-Mediated Currents and Plasticity of Cerebellar Synapses in Mice Expressing the GluN1(F639A) Subunit. Alcohol Clin Exp Res 2018; 42:698-705. [PMID: 29323417 DOI: 10.1111/acer.13597] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2017] [Accepted: 01/04/2018] [Indexed: 12/12/2022]
Abstract
BACKGROUND Glutamatergic N-methyl-d-aspartate receptors (NMDARs) are well known for their sensitivity to ethanol (EtOH) inhibition. However, the specific manner in which EtOH inhibits channel activity and how such inhibition affects neurotransmission, and ultimately behavior, remains unclear. Replacement of phenylalanine 639 with alanine (F639A) in the GluN1 subunit reduces EtOH inhibition of recombinant NMDARs. Mice expressing this subunit show reduced EtOH-induced anxiolysis, blunted locomotor stimulation following low-dose EtOH administration, and faster recovery of motor function after moderate doses of EtOH, suggesting that cerebellar dysfunction may contribute to some of these behaviors. In the mature mouse cerebellum, NMDARs at the cerebellar climbing fiber (CF) to Purkinje cell (PC) synapse are inhibited by low concentrations of EtOH and the long-term depression (LTD) of parallel fiber (PF)-mediated currents induced by concurrent activation of PFs and CFs (PF-LTD) requires activation of EtOH-sensitive NMDARs. In this study, we examined cerebellar NMDA responses and NMDA-mediated synaptic plasticity in wild-type (WT) and GluN1(F639A) mice. METHODS Patch-clamp electrophysiological recordings were performed in acute cerebellar slices from adult WT and GluN1(F639A) mice. NMDAR-mediated currents at the CF-PC synapse and NMDAR-dependent PF-LTD induction were compared for genotype-dependent differences. RESULTS Stimulation of CFs evoked robust NMDA-mediated excitatory postsynaptic currents (EPSCs) in PCs that were similar in amplitude and kinetics between WT and GluN1(F639A) mice. NMDA-mediated CF-PC EPSCs in WT mice were significantly inhibited by EtOH (50 mM) while those in mutant mice were unaffected. Concurrent stimulation of CF and PF inputs induced synaptic depression of PF-PC EPSCs in both WT and mutant mice, and this depression was blocked by the NMDA antagonist DL-APV. The synaptic depression of PF-PC EPSCs in WT mice was also blocked by a low concentration of EtOH (10 mM) that had no effect on plasticity in GluN1(F639A) mice. CONCLUSIONS These results demonstrate that inhibition of cerebellar NMDARs may be a key mechanism by which EtOH affects cerebellar-dependent behaviors.
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Affiliation(s)
- Paula A Zamudio-Bulcock
- Department of Neuroscience, Medical University of South Carolina, Charleston, South Carolina
| | - Gregg E Homanics
- Department of Anesthesiology, Univeristy of Pittsburgh, Pittsburgh, PA
| | - John J Woodward
- Department of Neuroscience, Medical University of South Carolina, Charleston, South Carolina
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Rompala GR, Mounier A, Wolfe CM, Lin Q, Lefterov I, Homanics GE. Heavy Chronic Intermittent Ethanol Exposure Alters Small Noncoding RNAs in Mouse Sperm and Epididymosomes. Front Genet 2018; 9:32. [PMID: 29472946 PMCID: PMC5809758 DOI: 10.3389/fgene.2018.00032] [Citation(s) in RCA: 73] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2017] [Accepted: 01/24/2018] [Indexed: 02/02/2023] Open
Abstract
While the risks of maternal alcohol abuse during pregnancy are well-established, several preclinical studies suggest that chronic preconception alcohol consumption by either parent may also have significance consequences for offspring health and development. Notably, since isogenic male mice used in these studies are not involved in gestation or rearing of offspring, the cross-generational effects of paternal alcohol exposure suggest a germline-based epigenetic mechanism. Many recent studies have demonstrated that the effects of paternal environmental exposures such as stress or malnutrition can be transmitted to the next generation via alterations to small noncoding RNAs in sperm. Therefore, we used high throughput sequencing to examine the effect of preconception ethanol on small noncoding RNAs in sperm. We found that chronic intermittent ethanol exposure altered several small noncoding RNAs from three of the major small RNA classes in sperm, tRNA-derived small RNA (tDR), mitochondrial small RNA, and microRNA. Six of the ethanol-responsive small noncoding RNAs were evaluated with RT-qPCR on a separate cohort of mice and five of the six were confirmed to be altered by chronic ethanol exposure, supporting the validity of the sequencing results. In addition to altered sperm RNA abundance, chronic ethanol exposure affected post-transcriptional modifications to sperm small noncoding RNAs, increasing two nucleoside modifications previously identified in mitochondrial tRNA. Furthermore, we found that chronic ethanol reduced epididymal expression of a tRNA methyltransferase, Nsun2, known to directly regulate tDR biogenesis. Finally, ethanol-responsive sperm tDR are similarly altered in extracellular vesicles of the epididymis (i.e., epididymosomes), supporting the hypothesis that alterations to sperm tDR emerge in the epididymis and that epididymosomes are the primary source of small noncoding RNAs in sperm. These results add chronic ethanol to the growing list of paternal exposures that can affect small noncoding RNA abundance and nucleoside modifications in sperm. As small noncoding RNAs in sperm have been shown to causally induce heritable phenotypes in offspring, additional research is warranted to understand the potential effects of ethanol-responsive sperm small noncoding RNAs on offspring health and development.
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Affiliation(s)
- Gregory R Rompala
- Center for Neuroscience, University of Pittsburgh, Pittsburgh, PA, United States
| | - Anais Mounier
- Department of Environmental and Occupational Health, University of Pittsburgh, Pittsburgh, PA, United States
| | - Cody M Wolfe
- Department of Environmental and Occupational Health, University of Pittsburgh, Pittsburgh, PA, United States
| | - Qishan Lin
- Mass Spectrometry Facility, Center for Functional Genomics, University at Albany, Rensselaer, NY, United States
| | - Iliya Lefterov
- Department of Environmental and Occupational Health, University of Pittsburgh, Pittsburgh, PA, United States
| | - Gregg E Homanics
- Center for Neuroscience, University of Pittsburgh, Pittsburgh, PA, United States.,Department of Anesthesiology, University of Pittsburgh, Pittsburgh, PA, United States.,Department of Pharmacology and Chemical Biology, University of Pittsburgh, Pittsburgh, PA, United States.,Department of Neurobiology, University of Pittsburgh, Pittsburgh, PA, United States
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33
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Pratt CP, Kuljis DA, Homanics GE, He J, Kolodieznyi D, Dudem S, Hollywood MA, Barth AL, Bruchez MP. Tagging of Endogenous BK Channels with a Fluorogen-Activating Peptide Reveals β4-Mediated Control of Channel Clustering in Cerebellum. Front Cell Neurosci 2017; 11:337. [PMID: 29163049 PMCID: PMC5671578 DOI: 10.3389/fncel.2017.00337] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2017] [Accepted: 10/12/2017] [Indexed: 01/10/2023] Open
Abstract
BK channels are critical regulators of neuronal activity, controlling firing, neurotransmitter release, cerebellar function, and BK channel mutations have been linked to seizure disorders. Modulation of BK channel gating is well characterized, regulated by accessory subunit interactions, intracellular signaling pathways, and membrane potential. In contrast, the role of intracellular trafficking mechanisms in controlling BK channel function, especially in live cells, has been less studied. Fluorogen-activating peptides (FAPs) are well-suited for trafficking and physiological studies due to the binding of malachite green (MG)-based dyes with sub-nanomolar affinity to the FAP, resulting in bright, photostable, far-red fluorescence. Cell-excluded MG dyes enable the selective tagging of surface protein and tracking through endocytic pathways. We used CRISPR to insert the FAP at the extracellular N-terminus of BKα in the first exon of its native locus, enabling regulation by the native promoter elements and tag incorporation into multiple splice isoforms. Motor coordination was found to be normal; however, BK channel expression seems to be reduced in some locations. Alternate start site selection or post-translational proteolytic processing resulted in incomplete FAP tagging of the BKα proteins in brain tissues. In Purkinje cell somata, FAP revealed BK channel clustering previously only observed by electron microscopy. Measurement of these clusters in β4+/- and β4-/- mice showed that puncta number and cluster fluorescence intensity on the soma are reduced in β4-/- knockout animals. This novel mouse line provides a versatile fluorescent platform for studying endogenous BK channels in living and fixed tissues. Future studies could apply this line to ex vivo neuronal cultures to study live-cell channel trafficking.
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Affiliation(s)
- Christopher P Pratt
- Department of Biological Sciences, Carnegie Mellon University, Pittsburgh, PA, United States.,Molecular Biosensor and Imaging Center, Carnegie Mellon University, Pittsburgh, PA, United States.,Center for the Neural Basis of Cognition, Carnegie Mellon University, Pittsburgh, PA, United States
| | - Dika A Kuljis
- Department of Biological Sciences, Carnegie Mellon University, Pittsburgh, PA, United States
| | - Gregg E Homanics
- Department of Anesthesiology, University of Pittsburgh, Pittsburgh, PA, United States.,Department of Neurobiology, University of Pittsburgh, Pittsburgh, PA, United States.,Department of Pharmacology and Chemical Biology, University of Pittsburgh, Pittsburgh, PA, United States
| | - Jianjun He
- Molecular Biosensor and Imaging Center, Carnegie Mellon University, Pittsburgh, PA, United States.,Department of Chemistry, Carnegie Mellon University, Pittsburgh, PA, United States
| | - Dmytro Kolodieznyi
- Molecular Biosensor and Imaging Center, Carnegie Mellon University, Pittsburgh, PA, United States.,Department of Chemistry, Carnegie Mellon University, Pittsburgh, PA, United States
| | - Srikanth Dudem
- Smooth Muscle Research Centre, Dundalk Institute of Technology, Dundalk, Ireland
| | - Mark A Hollywood
- Smooth Muscle Research Centre, Dundalk Institute of Technology, Dundalk, Ireland
| | - Alison L Barth
- Department of Biological Sciences, Carnegie Mellon University, Pittsburgh, PA, United States.,Center for the Neural Basis of Cognition, Carnegie Mellon University, Pittsburgh, PA, United States
| | - Marcel P Bruchez
- Department of Biological Sciences, Carnegie Mellon University, Pittsburgh, PA, United States.,Molecular Biosensor and Imaging Center, Carnegie Mellon University, Pittsburgh, PA, United States.,Department of Chemistry, Carnegie Mellon University, Pittsburgh, PA, United States
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Hill SY, Rompala G, Homanics GE, Zezza N. Cross-generational effects of alcohol dependence in humans on HRAS and TP53 methylation in offspring. Epigenomics 2017; 9:1189-1203. [PMID: 28799801 DOI: 10.2217/epi-2017-0052] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
AIM We hypothesized that cross-generational effects of alcohol exposure could alter DNA methylation and expression of the HRAS oncogene and TP53 tumor suppressor gene that drive cancer development. METHODS DNA methylation of the HRAS and TP53 genes was tested in samples from young participants (Mean age of 13.4 years). RESULTS Controlling for both personal use and maternal use of substances during pregnancy, familial alcohol dependence was associated with hypomethylation of CpG sites in the HRAS promoter region and hypermethylation of the TP53 gene. CONCLUSION The results suggest that ancestral exposure to alcohol can have enduring effects that impact epigenetic processes such as DNA methylation that controls expression of genes that drive cancer development such as HRAS and TP53.
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Affiliation(s)
- Shirley Y Hill
- Department of Psychiatry, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA
| | - Gregory Rompala
- Center for Neuroscience, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA
| | - Gregg E Homanics
- Departments of Anesthesiology & Pharmacology & Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA
| | - Nicholas Zezza
- Department of Psychiatry, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA
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Blednov YA, Borghese CM, Ruiz CI, Cullins MA, Da Costa A, Osterndorff-Kahanek EA, Homanics GE, Harris RA. Mutation of the inhibitory ethanol site in GABA A ρ1 receptors promotes tolerance to ethanol-induced motor incoordination. Neuropharmacology 2017. [PMID: 28623169 DOI: 10.1016/j.neuropharm.2017.06.013] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Genes encoding the ρ1/2 subunits of GABAA receptors have been associated with alcohol (ethanol) dependence in humans, and ρ1 was also shown to regulate some of the behavioral effects of ethanol in animal models. Ethanol inhibits GABA-mediated responses in wild-type (WT) ρ1, but not ρ1(T6'Y) mutant receptors expressed in Xenopus laevis oocytes, indicating the presence of an inhibitory site for ethanol in the second transmembrane helix. In this study, we found that ρ1(T6'Y) receptors expressed in oocytes display overall normal responses to GABA, the endogenous GABA modulator (zinc), and partial agonists (β-alanine and taurine). We generated ρ1 (T6'Y) knockin (KI) mice using CRISPR/Cas9 to test the behavioral importance of the inhibitory actions of ethanol on this receptor. Both ρ1 KI and knockout (KO) mice showed faster recovery from acute ethanol-induced motor incoordination compared to WT mice. Both KI and KO mutant strains also showed increased tolerance to motor impairment produced by ethanol. The KI mice did not differ from WT mice in other behavioral actions, including ethanol intake and preference, conditioned taste aversion to ethanol, and duration of ethanol-induced loss of righting reflex. WT and KI mice did not differ in levels of ρ1 or ρ2 mRNA in cerebellum or in ethanol clearance. Our findings indicate that the inhibitory site for ethanol in GABAA ρ1 receptors regulates acute functional tolerance to moderate ethanol intoxication. We note that low sensitivity to alcohol intoxication has been linked to risk for development of alcohol dependence in humans.
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Affiliation(s)
- Yuri A Blednov
- The University of Texas at Austin, Waggoner Center for Alcohol and Addiction Research, Austin, TX 78712, United States
| | - Cecilia M Borghese
- The University of Texas at Austin, Waggoner Center for Alcohol and Addiction Research, Austin, TX 78712, United States
| | - Carlos I Ruiz
- The University of Texas at Austin, Waggoner Center for Alcohol and Addiction Research, Austin, TX 78712, United States
| | - Madeline A Cullins
- The University of Texas at Austin, Waggoner Center for Alcohol and Addiction Research, Austin, TX 78712, United States
| | - Adriana Da Costa
- The University of Texas at Austin, Waggoner Center for Alcohol and Addiction Research, Austin, TX 78712, United States
| | | | - Gregg E Homanics
- University of Pittsburgh, Departments of Anesthesiology, Neurobiology, and Pharmacology & Chemical Biology, Pittsburgh, PA 15261, United States
| | - R Adron Harris
- The University of Texas at Austin, Waggoner Center for Alcohol and Addiction Research, Austin, TX 78712, United States.
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Yocum GT, Turner DL, Danielsson J, Barajas MB, Zhang Y, Xu D, Harrison NL, Homanics GE, Farber DL, Emala CW. GABA A receptor α 4-subunit knockout enhances lung inflammation and airway reactivity in a murine asthma model. Am J Physiol Lung Cell Mol Physiol 2017; 313:L406-L415. [PMID: 28473323 PMCID: PMC5582940 DOI: 10.1152/ajplung.00107.2017] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2017] [Revised: 04/06/2017] [Accepted: 04/30/2017] [Indexed: 01/07/2023] Open
Abstract
Emerging evidence indicates that hypnotic anesthetics affect immune function. Many anesthetics potentiate γ-aminobutyric acid A receptor (GABAAR) activation, and these receptors are expressed on multiple subtypes of immune cells, providing a potential mechanistic link. Like immune cells, airway smooth muscle (ASM) cells also express GABAARs, particularly isoforms containing α4-subunits, and activation of these receptors leads to ASM relaxation. We sought to determine if GABAAR signaling modulates the ASM contractile and inflammatory phenotype of a murine allergic asthma model utilizing GABAAR α4-subunit global knockout (KO; Gabra40/0 ) mice. Wild-type (WT) and Gabra4 KO mice were sensitized with house dust mite (HDM) antigen or exposed to PBS intranasally 5 days/wk for 3 wk. Ex vivo tracheal rings from HDM-sensitized WT and Gabra4 KO mice exhibited similar magnitudes of acetylcholine-induced contractile force and isoproterenol-induced relaxation (P = not significant; n = 4). In contrast, in vivo airway resistance (flexiVent) was significantly increased in Gabra4 KO mice (P < 0.05, n = 8). Moreover, the Gabra4 KO mice demonstrated increased eosinophilic lung infiltration (P < 0.05; n = 4) and increased markers of lung T-cell activation/memory (CD62L low, CD44 high; P < 0.01, n = 4). In vitro, Gabra4 KO CD4+ cells produced increased cytokines and exhibited increased proliferation after stimulation of the T-cell receptor as compared with WT CD4+ cells. These data suggest that the GABAAR α4-subunit plays a role in immune cell function during allergic lung sensitization. Thus GABAAR α4-subunit-specific agonists have the therapeutic potential to treat asthma via two mechanisms: direct ASM relaxation and inhibition of airway inflammation.
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Affiliation(s)
- Gene T Yocum
- Department of Anesthesiology, Columbia University, New York, New York;
| | - Damian L Turner
- Columbia Center for Translational Immunology, New York, New York
| | | | - Matthew B Barajas
- Department of Anesthesiology, Columbia University, New York, New York
| | - Yi Zhang
- Department of Anesthesiology, Columbia University, New York, New York
| | - Dingbang Xu
- Department of Anesthesiology, Columbia University, New York, New York
| | - Neil L Harrison
- Department of Anesthesiology, Columbia University, New York, New York.,Department of Pharmacology, Columbia University, New York, New York
| | - Gregg E Homanics
- Departments of Anesthesiology, Neurobiology, and Pharmacology and Chemical Biology, University of Pittsburgh, Pittsburgh, Pennsylvania; and
| | - Donna L Farber
- Columbia Center for Translational Immunology, New York, New York.,Department of Surgery and Microbiology and Immunology, Columbia University, New York, New York
| | - Charles W Emala
- Department of Anesthesiology, Columbia University, New York, New York
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Rompala GR, Finegersh A, Slater M, Homanics GE. Paternal preconception alcohol exposure imparts intergenerational alcohol-related behaviors to male offspring on a pure C57BL/6J background. Alcohol 2017; 60:169-177. [PMID: 27876231 DOI: 10.1016/j.alcohol.2016.11.001] [Citation(s) in RCA: 61] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2016] [Revised: 11/01/2016] [Accepted: 11/03/2016] [Indexed: 12/14/2022]
Abstract
While alcohol use disorder (AUD) is a highly heritable condition, the basis of AUD in families with a history of alcoholism is difficult to explain by genetic variation alone. Emerging evidence suggests that parental experience prior to conception can affect inheritance of complex behaviors in offspring via non-genomic (epigenetic) mechanisms. For instance, male C57BL/6J (B6) mice exposed to chronic intermittent vapor ethanol (CIE) prior to mating with Strain 129S1/SvImJ ethanol-naïve females produce male offspring with reduced ethanol-drinking preference, increased ethanol sensitivity, and increased brain-derived neurotrophic factor (BDNF) expression in the ventral tegmental area (VTA). In the present study, we tested the hypothesis that these intergenerational effects of paternal CIE are reproducible in male offspring on an inbred B6 background. To this end, B6 males were exposed to 6 weeks of CIE (or room air as a control) before mating with ethanol-naïve B6 females to produce ethanol (E)-sired and control (C)-sired male and female offspring. We observed a sex-specific effect, as E-sired males exhibited decreased two-bottle free-choice ethanol-drinking preference, increased sensitivity to the anxiolytic effects of ethanol, and increased VTA BDNF expression; no differences were observed in female offspring. These findings confirm and extend our previous results by demonstrating that the effects of paternal preconception ethanol are reproducible using genetically identical, inbred B6 animals.
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Affiliation(s)
- Amanda H Mahnke
- Department of Neuroscience and Experimental Therapeutics, College of Medicine, Texas A&M University Health Science Center, Bryan, TX, United States.
| | - Rajesh C Miranda
- Department of Neuroscience and Experimental Therapeutics, College of Medicine, Texas A&M University Health Science Center, Bryan, TX, United States
| | - Gregg E Homanics
- Department of Anesthesiology, University of Pittsburgh, Pittsburgh, PA, United States; Department of Neurobiology, University of Pittsburgh, Pittsburgh, PA, United States; Department of Pharmacology & Chemical Biology, University of Pittsburgh, Pittsburgh, PA, United States
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Ji X, Saha S, Gao G, Lasek AW, Homanics GE, Guildford M, Tapper AR, Martin GE. The Sodium Channel β4 Auxiliary Subunit Selectively Controls Long-Term Depression in Core Nucleus Accumbens Medium Spiny Neurons. Front Cell Neurosci 2017; 11:17. [PMID: 28243192 PMCID: PMC5303751 DOI: 10.3389/fncel.2017.00017] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2016] [Accepted: 01/19/2017] [Indexed: 12/19/2022] Open
Abstract
Voltage-gated sodium channels are essential for generating the initial rapid depolarization of neuronal membrane potential during action potentials (APs) that enable cell-to-cell communication, the propagation of signals throughout the brain, and the induction of synaptic plasticity. Although all brain neurons express one or several variants coding for the core pore-forming sodium channel α subunit, the expression of the β (β1–4) auxiliary subunits varies greatly. Of particular interest is the β4 subunit, encoded by the Scn4b gene, that is highly expressed in dorsal and ventral (i.e., nucleus accumbens – NAc) striata compared to other brain regions, and that endows sodium channels with unique gating properties. However, its role on neuronal activity, synaptic plasticity, and behaviors related to drugs of abuse remains poorly understood. Combining whole-cell patch-clamp recordings with two-photon calcium imaging in Scn4b knockout (KO) and knockdown mice, we found that Scn4b altered the properties of APs in core accumbens medium spiny neurons (MSNs). These alterations are associated with a reduction of the probability of MSNs to evoke spike-timing-dependent long-term depression (tLTD) and a reduced ability of backpropagating APs to evoke dendritic calcium transients. In contrast, long-term potentiation (tLTP) remained unaffected. Interestingly, we also showed that amphetamine-induced locomotor activity was significantly reduced in male Scn4b KO mice compared to wild-type controls. Taken together, these data indicate that the Scn4b subunit selectively controls tLTD by modulating dendritic calcium transients evoked by backpropagating APs.
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Affiliation(s)
- Xincai Ji
- Department of Psychiatry, The Brudnick Neuropsychiatric Research Institute, University of Massachusetts Medical School, Worcester MA, USA
| | - Sucharita Saha
- Department of Psychiatry, The Brudnick Neuropsychiatric Research Institute, University of Massachusetts Medical School, Worcester MA, USA
| | - Guangping Gao
- Gene Therapy Center, University of Massachusetts Medical School, Worcester MA, USA
| | - Amy W Lasek
- Department of Psychiatry, University of Illinois at Chicago, Chicago IL, USA
| | - Gregg E Homanics
- Department of Anesthesiology, University of Pittsburgh, Pittsburgh PA, USA
| | - Melissa Guildford
- Department of Psychiatry, The Brudnick Neuropsychiatric Research Institute, University of Massachusetts Medical School, Worcester MA, USA
| | - Andrew R Tapper
- Department of Psychiatry, The Brudnick Neuropsychiatric Research Institute, University of Massachusetts Medical School, Worcester MA, USA
| | - Gilles E Martin
- Department of Psychiatry, The Brudnick Neuropsychiatric Research Institute, University of Massachusetts Medical School, Worcester MA, USA
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den Hartog CR, Gilstrap M, Eaton B, Lench DH, Mulholland PJ, Homanics GE, Woodward JJ. Effects of Repeated Ethanol Exposures on NMDA Receptor Expression and Locomotor Sensitization in Mice Expressing Ethanol Resistant NMDA Receptors. Front Neurosci 2017; 11:84. [PMID: 28270746 PMCID: PMC5318453 DOI: 10.3389/fnins.2017.00084] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2016] [Accepted: 02/06/2017] [Indexed: 11/13/2022] Open
Abstract
Evidence from a large number of preclinical studies suggests that chronic exposure to drugs of abuse, such as psychostimulants or ethanol induces changes in glutamatergic transmission in key brain areas associated with reward and control of behavior. These changes include alterations in the expression of ionotropic glutamate receptors including N-methyl-D-aspartate receptors (NMDAR) that are important for regulating neuronal activity and synaptic plasticity. NMDA receptors are inhibited by ethanol and reductions in NMDA-mediated signaling are thought to trigger homestatic responses that limit ethanol's effects on glutamatergic transmission. Following repeated exposures to ethanol, these homeostatic responses may become unstable leading to an altered glutamatergic state that contributes to the escalations in drinking and cognitive deficits observed in alcohol-dependent subjects. An important unanswered question is whether ethanol-induced changes in NMDAR expression are modulated by the intrinsic sensitivity of the receptor to ethanol. In this study, we examined the effects of ethanol on NMDAR subunit expression in cortical (orbitofrontal, medial prefrontal), striatal (dorsal and ventral striatum) and limbic (dorsal hippocampus, basolateral amygdala) areas in mice genetically modified to express ethanol-resistant receptors (F639A mice). These mice have been previously shown to drink more ethanol than their wild-type counterparts and have altered behavioral responses to certain actions of ethanol. Following long-term voluntary drinking, F639A mice showed elevations in GluN2A but not GluN1 or GluN2B expression as compared to wild-type mice. Mice treated with repeated injections with ethanol (2-3.5 g/kg; i.p.) showed changes in NMDAR expression that varied in a complex manner with genotype, brain region, subunit type and exposure protocol all contributing to the observed response. F639A mice, but not wild-type mice, showed enhanced motor activity following repeated ethanol injections and this was associated with differences in NMDAR subunit expression across brain regions thought to be involved in drug sensitization. Overall, while the results of the study suggest that NMDARs with reduced sensitivity to ethanol favor the development of locomotor sensitization, they also show that intrinsic ethanol sensitivity is not the sole determinant underlying changes in NMDAR expression following repeated exposures to ethanol.
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Affiliation(s)
- Carolina R den Hartog
- Department of Neuroscience, Medical University of South Carolina Charleston, SC, USA
| | - Meghin Gilstrap
- Department of Neuroscience, Medical University of South Carolina Charleston, SC, USA
| | - Bethany Eaton
- Department of Neuroscience, Medical University of South Carolina Charleston, SC, USA
| | - Daniel H Lench
- Department of Neuroscience, Medical University of South Carolina Charleston, SC, USA
| | - Patrick J Mulholland
- Department of Neuroscience, Medical University of South Carolina Charleston, SC, USA
| | - Gregg E Homanics
- Department of Anesthesiology, University of Pittsburgh Pittsburgh, PA, USA
| | - John J Woodward
- Department of Neuroscience, Medical University of South Carolina Charleston, SC, USA
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Rompala GR, Finegersh A, Homanics GE. Paternal preconception ethanol exposure blunts hypothalamic-pituitary-adrenal axis responsivity and stress-induced excessive fluid intake in male mice. Alcohol 2016; 53:19-25. [PMID: 27286933 DOI: 10.1016/j.alcohol.2016.03.006] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2016] [Revised: 03/10/2016] [Accepted: 03/25/2016] [Indexed: 12/18/2022]
Abstract
A growing number of environmental insults have been shown to induce epigenetic effects that persist across generations. For instance, paternal preconception exposures to ethanol or stress have independently been shown to exert such intergenerational effects. Since ethanol exposure is a physiological stressor that activates the hypothalamic-pituitary-adrenal (HPA) axis, we hypothesized that paternal ethanol exposure would impact stress responsivity of offspring. Adult male mice were exposed to chronic intermittent vapor ethanol or control conditions for 5 weeks before being mated with ethanol-naïve females to produce ethanol (E)- and control (C)-sired offspring. Adult male and female offspring were tested for plasma corticosterone (CORT) levels following acute restraint stress and the male offspring were further examined for stress-evoked 2-bottle choice ethanol-drinking. Paternal ethanol exposure blunted plasma CORT levels following acute restraint stress selectively in male offspring; females were unaffected. In a stress-evoked ethanol-drinking assay, there was no effect of stress on ethanol consumption. However, C-sired males exhibited increased total fluid intake (polydipsia) in response to stress while E-sired males were resistant to this stress-induced phenotype. Taken together, these data suggest that paternal ethanol exposure imparts stress hyporesponsivity to male offspring.
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Finegersh A, Homanics GE. Chromatin immunoprecipitation and gene expression analysis of neuronal subtypes after fluorescence activated cell sorting. J Neurosci Methods 2016; 263:81-8. [PMID: 26868730 DOI: 10.1016/j.jneumeth.2016.02.006] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2015] [Revised: 01/15/2016] [Accepted: 02/01/2016] [Indexed: 12/22/2022]
Abstract
BACKGROUND With advances in cell capture, gene expression can now be studied in neuronal subtypes and single cells; however, studying epigenetic mechanisms that underlie these changes presents challenges. Moreover, chromatin immunoprecipitation (ChIP) protocols optimized for low cell number do not adequately address technical issues and cell loss while preparing tissue for fluorescence activated cell sorting (FACS). Developing a reliable FACS-ChIP protocol without the need for pooling tissue from multiple animals would enable study of epigenetic mechanisms in neuronal subtypes. METHODS FACS was used to isolate dopamine 1 receptor (D1R) expressing cells from the nucleus accumbens (NAc) of a commercially available BAC transgenic mouse strain. D1R+ cells were used to study gene expression as well as histone modifications at gene promoters using a novel native ChIP protocol. RESULTS Isolated cells had enrichment of the dopamine 1 receptor (D1R) mRNA and nearly undetectable levels of GFAP and D2R mRNA. ChIP analysis demonstrated the association of activating or repressive histone modifications with highly expressed or silent gene promoters, respectively. COMPARISON WITH EXISTING METHODS The ChIP protocol developed in this paper enables characterization of histone modifications from ∼30,000 FAC-sorted neurons. CONCLUSIONS We describe a one day FACS-ChIP protocol that can be applied to epigenetic studies of neuronal subtypes without pooling tissue.
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Affiliation(s)
- Andrey Finegersh
- University of Pittsburgh, Departments of Anesthesiology and Pharmacology & Chemical Biology, 6060 Biomedical Science Tower-3, 3501 Fifth Avenue, Pittsburgh, PA 15261, United States
| | - Gregg E Homanics
- University of Pittsburgh, Departments of Anesthesiology and Pharmacology & Chemical Biology, 6060 Biomedical Science Tower-3, 3501 Fifth Avenue, Pittsburgh, PA 15261, United States.
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Cai X, Huang H, Kuzirian MS, Snyder LM, Matsushita M, Lee MC, Ferguson C, Homanics GE, Barth AL, Ross SE. Generation of a KOR-Cre knockin mouse strain to study cells involved in kappa opioid signaling. Genesis 2015; 54:29-37. [PMID: 26575788 DOI: 10.1002/dvg.22910] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2015] [Revised: 10/26/2015] [Accepted: 11/15/2015] [Indexed: 01/06/2023]
Abstract
The kappa opioid receptor (KOR) has numerous important roles in the nervous system including the modulation of mood, reward, pain, and itch. In addition, KOR is expressed in many non-neuronal tissues. However, the specific cell types that express KOR are poorly characterized. Here, we report the development of a KOR-Cre knockin allele, which provides genetic access to cells that express KOR. In this mouse, Cre recombinase (Cre) replaces the initial coding sequence of the Opkr1 gene (encoding the kappa opioid receptor). We demonstrate that the KOR-Cre allele mediates recombination by embryonic day 14.5 (E14.5). Within the brain, KOR-Cre shows expression in numerous areas including the cerebral cortex, nucleus accumbens and striatum. In addition, this allele is expressed in epithelium and throughout many regions of the body including the heart, lung, and liver. Finally, we reveal that KOR-Cre mediates recombination of a subset of bipolar and amacrine cells in the retina. Thus, the KOR-Cre mouse line is a valuable new tool for conditional gene manipulation to enable the study of KOR.
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Affiliation(s)
- Xiaoyun Cai
- Department of Neurobiology and the Pittsburgh Center for Pain Research, University of Pittsburgh, Pittsburgh, PA, USA
| | - Huizhen Huang
- Department of Neurobiology and the Pittsburgh Center for Pain Research, University of Pittsburgh, Pittsburgh, PA, USA.,Tsinghua University School of Medicine, Beijing, China
| | - Marissa S Kuzirian
- Department of Neurobiology and the Pittsburgh Center for Pain Research, University of Pittsburgh, Pittsburgh, PA, USA
| | - Lindsey M Snyder
- Department of Neurobiology and the Pittsburgh Center for Pain Research, University of Pittsburgh, Pittsburgh, PA, USA
| | - Megumi Matsushita
- Department of Biological Sciences and Center for the Neural Basis of Cognition, Carnegie Mellon University, Pittsburgh, PA, USA
| | - Michael C Lee
- Department of Neurobiology and the Pittsburgh Center for Pain Research, University of Pittsburgh, Pittsburgh, PA, USA
| | - Carolyn Ferguson
- Departments of Anesthesiology and Pharmacology & Chemical Biology, University of Pittsburgh, Pittsburgh, PA, USA
| | - Gregg E Homanics
- Departments of Anesthesiology and Pharmacology & Chemical Biology, University of Pittsburgh, Pittsburgh, PA, USA
| | - Alison L Barth
- Department of Biological Sciences and Center for the Neural Basis of Cognition, Carnegie Mellon University, Pittsburgh, PA, USA
| | - Sarah E Ross
- Department of Neurobiology and the Pittsburgh Center for Pain Research, University of Pittsburgh, Pittsburgh, PA, USA
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Finegersh A, Ferguson C, Maxwell S, Mazariegos D, Farrell D, Homanics GE. Repeated vapor ethanol exposure induces transient histone modifications in the brain that are modified by genotype and brain region. Front Mol Neurosci 2015; 8:39. [PMID: 26300722 PMCID: PMC4524924 DOI: 10.3389/fnmol.2015.00039] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2015] [Accepted: 07/10/2015] [Indexed: 01/01/2023] Open
Abstract
Background: Emerging research implicates ethanol (EtOH)-induced epigenetic modifications in regulating gene expression and EtOH consumption. However, consensus on specific epigenetic modifications induced by EtOH has not yet emerged, making it challenging to identify mechanisms and develop targeted treatments. We hypothesized that chronic intermittent EtOH (CIE) induces persistent changes in histone modifications across the cerebral cortex (CCx), nucleus accumbens (NAc), and prefrontal cortex (PFC), and that these histone modifications are altered in a knock-in mouse strain with altered sensitivity to EtOH. Methods: C57BL/6J (B6) mice and α1SHLA knockin mice on a B6 background were exposed to 16 h of vapor EtOH or room air followed by 8 h of room air for 4 consecutive days and sacrificed at multiple time points up to 72 h following exposure. Histone modifications were assessed using Western blot and dot blot. RT-qPCR was used to study expression of chromatin modifying enzymes in NAc and PFC. Results: In NAc, CIE significantly increased acetylation of histone subunit H3 at lysine 9 (H3K9ac) but not lysine 14 (H3K14ac) or lysine 27 (H3K27ac). In PFC, CIE significantly increased H3K9ac but not H3K14 or H3K27ac. There were no significant changes at 8 or 72 h after EtOH exposure in either NAc or PFC. CIE was also associated with increased expression of Kat2b, Kat5, and Tet1 in NAc but not PFC. In CCx, CIE had a significant effect on levels of H3K18ac; there was also a significant effect of the α1SHLA mutation on levels of H3K27me3, H3K14ac, and H3K18ac as well as a trend for H3S10pK14ac. Conclusions: The EtOH-induced histone modifications observed were transient and varied significantly between brain regions. A genetic mutation that altered sensitivity to EtOH was associated with altered induction of histone modifications during CIE. These results have implications for studying EtOH-induced histone modifications and EtOH sensitivity.
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Affiliation(s)
- Andrey Finegersh
- Departments of Anesthesiology, Pharmacology and Chemical Biology, University of Pittsburgh Pittsburgh, PA, USA
| | - Carolyn Ferguson
- Departments of Anesthesiology, Pharmacology and Chemical Biology, University of Pittsburgh Pittsburgh, PA, USA
| | - Seth Maxwell
- Departments of Anesthesiology, Pharmacology and Chemical Biology, University of Pittsburgh Pittsburgh, PA, USA
| | - David Mazariegos
- Departments of Anesthesiology, Pharmacology and Chemical Biology, University of Pittsburgh Pittsburgh, PA, USA
| | - Daniel Farrell
- Departments of Anesthesiology, Pharmacology and Chemical Biology, University of Pittsburgh Pittsburgh, PA, USA
| | - Gregg E Homanics
- Departments of Anesthesiology, Pharmacology and Chemical Biology, University of Pittsburgh Pittsburgh, PA, USA
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Izpisua Belmonte JC, Callaway EM, Caddick SJ, Churchland P, Feng G, Homanics GE, Lee KF, Leopold DA, Miller CT, Mitchell JF, Mitalipov S, Moutri AR, Movshon JA, Okano H, Reynolds JH, Ringach D, Sejnowski TJ, Silva AC, Strick PL, Wu J, Zhang F. Brains, genes, and primates. Neuron 2015; 86:617-31. [PMID: 25950631 DOI: 10.1016/j.neuron.2015.03.021] [Citation(s) in RCA: 188] [Impact Index Per Article: 20.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
One of the great strengths of the mouse model is the wide array of genetic tools that have been developed. Striking examples include methods for directed modification of the genome, and for regulated expression or inactivation of genes. Within neuroscience, it is now routine to express reporter genes, neuronal activity indicators, and opsins in specific neuronal types in the mouse. However, there are considerable anatomical, physiological, cognitive, and behavioral differences between the mouse and the human that, in some areas of inquiry, limit the degree to which insights derived from the mouse can be applied to understanding human neurobiology. Several recent advances have now brought into reach the goal of applying these tools to understanding the primate brain. Here we describe these advances, consider their potential to advance our understanding of the human brain and brain disorders, discuss bioethical considerations, and describe what will be needed to move forward.
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Affiliation(s)
- Juan Carlos Izpisua Belmonte
- Gene Expression Laboratory, The Salk Institute for Biological Studies, 10010 North Torrey Pines Road, La Jolla, CA 92037, USA
| | - Edward M Callaway
- Systems Neurobiology Laboratory, The Salk Institute for Biological Studies, 10010 North Torrey Pines Road, La Jolla, CA 92037, USA
| | - Sarah J Caddick
- The Gatsby Charitable Foundation, The Peak, 5 Wilton Road, London SW1V 1AP, UK
| | - Patricia Churchland
- Department of Philosophy, University of California, San Diego, 1500 Gilman Drive, La Jolla, CA 92093, USA
| | - Guoping Feng
- Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, 43 Vassar Street, Cambridge, MA 02139, USA
| | - Gregg E Homanics
- Department of Anesthesiology and Pharmacology and Department of Chemical Biology, University of Pittsburgh, 6060 Biomedical Science Tower 3, Pittsburgh, PA 15261, USA
| | - Kuo-Fen Lee
- Clayton Foundation Laboratories for Peptide Biology, The Salk Institute for Biological Studies, 10010 North Torrey Pines Road, La Jolla, CA 92037, USA
| | - David A Leopold
- Section on Cognitive Neurophysiology and Imaging, Laboratory of Neuropsychology, National Institute of Mental Health, National Institutes of Health, Bethesda, MD 20192, USA
| | - Cory T Miller
- Department of Psychology and Neurosciences Graduate Program, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093, USA
| | - Jude F Mitchell
- Brain and Cognitive Sciences, Meliora Hall, Box 270268, University of Rochester, Rochester, NY 14627-0268, USA
| | - Shoukhrat Mitalipov
- Center for Embryonic Cell and Gene Therapy, Oregon Health and Science University, 3303 S.W. Bond Avenue, Portland, OR 97239, USA; Division of Reproductive and Developmental Sciences, Oregon National Primate Research Center, Oregon Health and Science University, 505 N.W. 185th Avenue, Beaverton, OR 97006, USA
| | - Alysson R Moutri
- School of Medicine, Department of Pediatrics/Rady Children's Hospital San Diego, and Department of Cellular and Molecular Medicine, Stem Cell Program, 9500 Gilman Drive, La Jolla, CA 92093, USA
| | - J Anthony Movshon
- Center for Neural Science, New York University, New York, NY 10003, USA
| | - Hideyuki Okano
- Department of Physiology, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582, Japan; Laboratory for Marmoset Neural Architecture, Brain Science Institute RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| | - John H Reynolds
- Systems Neurobiology Laboratory, The Salk Institute for Biological Studies, 10010 North Torrey Pines Road, La Jolla, CA 92037, USA.
| | - Dario Ringach
- Department of Neurobiology and Department of Psychology, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA 92093, USA
| | - Terrence J Sejnowski
- Computational Neurobiology Laboratory, The Salk Institute for Biological Studies, 10010 North Torrey Pines Road, La Jolla, CA 92037, USA
| | - Afonso C Silva
- Laboratory of Functional and Molecular Imaging, National Institute of Neurological Disorders and Stroke, National Institutes of Health, 49 Convent Drive, MSC 1065, Building 49, Room 3A72, Bethesda, MD 20892-1065, USA
| | - Peter L Strick
- Brain Institute and Center for the Neural Basis of Cognition, University of Pittsburgh School of Medicine, Pittsburgh, PA 15261, USA; Department of Neurobiology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15261, USA; Research Service, Department of Veterans Affairs Medical Center, Pittsburgh, PA 15261, USA
| | - Jun Wu
- Gene Expression Laboratory, The Salk Institute for Biological Studies, 10010 North Torrey Pines Road, La Jolla, CA 92037, USA
| | - Feng Zhang
- Broad Institute of Harvard and MIT, 415 Main Street, Cambridge, MA 02142, USA; McGovern Institute for Brain Research at MIT, 43 Vassar Street, Cambridge, MA 02139, USA; Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, 7 Massachusetts Avenue, Cambridge, MA 02139, USA; Department of Biological Engineering, Massachusetts Institute of Technology, 7 Massachusetts Avenue, Cambridge, MA 02139, USA; Stanley Center for Psychiatric Research, Broad Institute of Harvard and MIT, 415 Main Street, Cambridge, MA 02142, USA
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Jaiswal MK, Keros S, Zhao M, Inan M, Schwartz TH, Anderson SA, Homanics GE, Goldstein PA. Reduction in focal ictal activity following transplantation of MGE interneurons requires expression of the GABAA receptor α4 subunit. Front Cell Neurosci 2015; 9:127. [PMID: 25914623 PMCID: PMC4391265 DOI: 10.3389/fncel.2015.00127] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2015] [Accepted: 03/18/2015] [Indexed: 12/14/2022] Open
Abstract
Despite numerous advances, treatment-resistant seizures remain an important problem. Loss of neuronal inhibition is present in a variety of epilepsy models and is suggested as a mechanism for increased excitability, leading to the proposal that grafting inhibitory interneurons into seizure foci might relieve refractory seizures. Indeed, transplanted medial ganglionic eminence interneuron progenitors (MGE-IPs) mature into GABAergic interneurons that increase GABA release onto cortical pyramidal neurons, and this inhibition is associated with reduced seizure activity. An obvious conclusion is that inhibitory coupling between the new interneurons and pyramidal cells underlies this effect. We hypothesized that the primary mechanism for the seizure-limiting effects following MGE-IP transplantation is the tonic conductance that results from activation of extrasynaptic GABAA receptors (GABAA-Rs) expressed on cortical pyramidal cells. Using in vitro and in vivo recording techniques, we demonstrate that GABAA-R α4 subunit deletion abolishes tonic currents (Itonic) in cortical pyramidal cells and leads to a failure of MGE-IP transplantation to attenuate cortical seizure propagation. These observations should influence how the field proceeds with respect to the further development of therapeutic neuronal transplants (and possibly pharmacological treatments).
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Affiliation(s)
- Manoj K Jaiswal
- C.V. Starr Laboratory for Molecular Neuropharmacology, Department of Anesthesiology, Weill Cornell Medical College New York, NY, USA
| | - Sotirios Keros
- Department of Pediatrics, Weill Cornell Medical College New York, NY, USA
| | - Mingrui Zhao
- Department of Neurological Surgery, Weill Cornell Medical College New York, NY, USA ; Brain and Mind Research Institute, Weill Cornell Medical College New York, NY, USA
| | - Melis Inan
- Brain and Mind Research Institute, Weill Cornell Medical College New York, NY, USA
| | - Theodore H Schwartz
- Department of Neurological Surgery, Weill Cornell Medical College New York, NY, USA ; Brain and Mind Research Institute, Weill Cornell Medical College New York, NY, USA
| | - Stewart A Anderson
- Department of Psychiatry, Children's Hospital of Philadelphia, University of Pennsylvania School of Medicine Philadelphia, PA, USA
| | - Gregg E Homanics
- Department of Anesthesiology, University of Pittsburgh Pittsburgh, PA, USA
| | - Peter A Goldstein
- C.V. Starr Laboratory for Molecular Neuropharmacology, Department of Anesthesiology, Weill Cornell Medical College New York, NY, USA
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Naito A, Muchhala KH, Trang J, Asatryan L, Trudell JR, Homanics GE, Alkana RL, Davies DL. Manipulations of extracellular Loop 2 in α1 GlyR ultra-sensitive ethanol receptors (USERs) enhance receptor sensitivity to isoflurane, ethanol, and lidocaine, but not propofol. Neuroscience 2015; 297:68-77. [PMID: 25827497 DOI: 10.1016/j.neuroscience.2015.03.034] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2015] [Revised: 03/16/2015] [Accepted: 03/17/2015] [Indexed: 11/18/2022]
Abstract
We recently developed ultra-sensitive ethanol receptors (USERs) as a novel tool for investigation of single receptor subunit populations sensitized to extremely low ethanol concentrations that do not affect other receptors in the nervous system. To this end, we found that mutations within the extracellular Loop 2 region of glycine receptors (GlyRs) and γ-aminobutyric acid type A receptors (GABAARs) can significantly increase receptor sensitivity to micro-molar concentrations of ethanol resulting in up to a 100-fold increase in ethanol sensitivity relative to wild-type (WT) receptors. The current study investigated: (1) Whether structural manipulations of Loop 2 in α1 GlyRs could similarly increase receptor sensitivity to other anesthetics; and (2) If mutations exclusive to the C-terminal end of Loop 2 are sufficient to impart these changes. We expressed α1 GlyR USERs in Xenopus oocytes and tested the effects of three classes of anesthetics, isoflurane (volatile), propofol (intravenous), and lidocaine (local), known to enhance glycine-induced chloride currents using two-electrode voltage clamp electrophysiology. Loop 2 mutations produced a significant 10-fold increase in isoflurane and lidocaine sensitivity, but no increase in propofol sensitivity compared to WT α1 GlyRs. Interestingly, we also found that structural manipulations in the C-terminal end of Loop 2 were sufficient and selective for α1 GlyR modulation by ethanol, isoflurane, and lidocaine. These studies are the first to report the extracellular region of α1 GlyRs as a site of lidocaine action. Overall, the findings suggest that Loop 2 of α1 GlyRs is a key region that mediates isoflurane and lidocaine modulation. Moreover, the results identify important amino acids in Loop 2 that regulate isoflurane, lidocaine, and ethanol action. Collectively, these data indicate the commonality of the sites for isoflurane, lidocaine, and ethanol action, and the structural requirements for allosteric modulation on α1 GlyRs within the extracellular Loop 2 region.
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Affiliation(s)
- A Naito
- Department of Pharmacology and Pharmaceutical Sciences, University of Southern California, School of Pharmacy, 1985 Zonal Avenue, Los Angeles, CA 90089, USA
| | - K H Muchhala
- Department of Pharmacology and Pharmaceutical Sciences, University of Southern California, School of Pharmacy, 1985 Zonal Avenue, Los Angeles, CA 90089, USA
| | - J Trang
- Department of Pharmacology and Pharmaceutical Sciences, University of Southern California, School of Pharmacy, 1985 Zonal Avenue, Los Angeles, CA 90089, USA
| | - L Asatryan
- Titus Family Department of Clinical Pharmacy and Pharmaceutical Economics and Policy, University of Southern California, School of Pharmacy, 1985 Zonal Avenue, Los Angeles, CA 90089, USA
| | - J R Trudell
- Department of Anesthesia, Beckman Program for Molecular and Genetic Medicine, Stanford University, Stanford University Medical Center, Stanford, CA 94305, USA
| | - G E Homanics
- Department of Anesthesiology, University of Pittsburgh, 6060 Biomedical Science Tower 3, Pittsburgh, PA 15261, USA; Department of Pharmacology and Chemical Biology, University of Pittsburgh, 6060 Biomedical Science Tower 3, Pittsburgh, PA 15261, USA
| | - R L Alkana
- Department of Pharmacology and Pharmaceutical Sciences, University of Southern California, School of Pharmacy, 1985 Zonal Avenue, Los Angeles, CA 90089, USA
| | - D L Davies
- Titus Family Department of Clinical Pharmacy and Pharmaceutical Economics and Policy, University of Southern California, School of Pharmacy, 1985 Zonal Avenue, Los Angeles, CA 90089, USA.
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Aguayo LG, Castro P, Mariqueo T, Muñoz B, Xiong W, Zhang L, Lovinger DM, Homanics GE. Altered sedative effects of ethanol in mice with α1 glycine receptor subunits that are insensitive to Gβγ modulation. Neuropsychopharmacology 2014; 39:2538-48. [PMID: 24801766 PMCID: PMC4207329 DOI: 10.1038/npp.2014.100] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/08/2013] [Revised: 03/20/2014] [Accepted: 03/21/2014] [Indexed: 12/17/2022]
Abstract
Alcohol abuse and alcoholism are major health problems and one of the leading preventable causes of death. Before achieving better treatments for alcoholism, it is necessary to understand the critical actions of alcohol on membrane proteins that regulate fundamental functions in the central nervous system. After generating a genetically modified knock-in (KI) mouse having a glycine receptor (GlyR) with phenotypical silent mutations at KK385/386AA, we studied its cellular and in vivo ethanol sensitivity. Analyses with western blotting and immunocytochemistry indicated that the expression of α1 GlyRs in nervous tissues and spinal cord neurons (SCNs) were similar between WT and KI mice. The analysis of synaptic currents recorded from KI mice showed that the glycinergic synaptic transmission had normal properties, but the sensitivity to ethanol was significantly reduced. Furthermore, the glycine-evoked current in SCNs from KI was resistant to ethanol and G-protein activation by GTP-γ-S. In behavioral studies, KI mice did not display the foot-clasping behavior upon lifting by the tail and lacked an enhanced startle reflex response that are characteristic of other glycine KI mouse lines with markedly impaired glycine receptor function. The most notable characteristic of the KI mice was their significant lower sensitivity to ethanol (∼40%), expressed by shorter times in loss of righting reflex (LORR) in response to a sedative dose of ethanol (3.5 g/Kg). These data provide the first evidence to link a molecular site in the GlyR with the sedative effects produced by intoxicating doses of ethanol.
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Affiliation(s)
- Luis G Aguayo
- Laboratory of Neurophysiology, Department of Physiology, University of Concepcion, Concepcion, Chile,Department of Physiology, University of Concepcion, PO BOX 160C, Concepcion 4030001, Chile. E-mail:
| | - Patricio Castro
- Laboratory of Neurophysiology, Department of Physiology, University of Concepcion, Concepcion, Chile
| | - Trinidad Mariqueo
- Laboratory of Neurophysiology, Department of Physiology, University of Concepcion, Concepcion, Chile
| | - Braulio Muñoz
- Laboratory of Neurophysiology, Department of Physiology, University of Concepcion, Concepcion, Chile
| | - Wei Xiong
- Laboratory for Integrative Neuroscience, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, MD, USA
| | - Li Zhang
- 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
| | - Gregg E Homanics
- Departments of Anesthesiology and Pharmacology and Chemical Biology, University of Pittsburgh, Pittsburgh, PA, USA,Departments of Anesthesiology and Pharmacology and Chemical Biology, University of Pittsburgh, Pittsburgh, PA, USA. E-mail:
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Naito A, Muchhala KH, Asatryan L, Trudell JR, Homanics GE, Perkins DI, Davies DL, Alkana RL. Glycine and GABA(A) ultra-sensitive ethanol receptors as novel tools for alcohol and brain research. Mol Pharmacol 2014; 86:635-46. [PMID: 25245406 DOI: 10.1124/mol.114.093773] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
A critical obstacle to developing effective medications to prevent and/or treat alcohol use disorders is the lack of specific knowledge regarding the plethora of molecular targets and mechanisms underlying alcohol (ethanol) action in the brain. To identify the role of individual receptor subunits in ethanol-induced behaviors, we developed a novel class of ultra-sensitive ethanol receptors (USERs) that allow activation of a single receptor subunit population sensitized to extremely low ethanol concentrations. USERs were created by mutating as few as four residues in the extracellular loop 2 region of glycine receptors (GlyRs) or γ-aminobutyric acid type A receptors (GABA(A)Rs), which are implicated in causing many behavioral effects linked to ethanol abuse. USERs, expressed in Xenopus oocytes and tested using two-electrode voltage clamp, demonstrated an increase in ethanol sensitivity of 100-fold over wild-type receptors by significantly decreasing the threshold and increasing the magnitude of ethanol response, without altering general receptor properties including sensitivity to the neurosteroid, allopregnanolone. These profound changes in ethanol sensitivity were observed across multiple subunits of GlyRs and GABA(A)Rs. Collectively, our studies set the stage for using USER technology in genetically engineered animals as a unique tool to increase understanding of the neurobiological basis of the behavioral effects of ethanol.
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Affiliation(s)
- Anna Naito
- Department of Pharmacology and Pharmaceutical Sciences (A.N., K.H.M., R.L.A.) and Titus Family Department of Clinical Pharmacy and Pharmaceutical Economics and Policy (L.A., D.L.D.), University of Southern California School of Pharmacy, Los Angeles, California; Department of Anesthesia, Beckman Program for Molecular and Genetic Medicine, Stanford University, Stanford University Medical Center, Stanford, California (J.R.T.); Departments of Anesthesiology and Pharmacology and Chemical Biology, University of Pittsburgh, Pittsburgh, Pennsylvania (G.E.H.); and Amgen Inc., Thousand Oaks, California (D.I.P.)
| | - Karan H Muchhala
- Department of Pharmacology and Pharmaceutical Sciences (A.N., K.H.M., R.L.A.) and Titus Family Department of Clinical Pharmacy and Pharmaceutical Economics and Policy (L.A., D.L.D.), University of Southern California School of Pharmacy, Los Angeles, California; Department of Anesthesia, Beckman Program for Molecular and Genetic Medicine, Stanford University, Stanford University Medical Center, Stanford, California (J.R.T.); Departments of Anesthesiology and Pharmacology and Chemical Biology, University of Pittsburgh, Pittsburgh, Pennsylvania (G.E.H.); and Amgen Inc., Thousand Oaks, California (D.I.P.)
| | - Liana Asatryan
- Department of Pharmacology and Pharmaceutical Sciences (A.N., K.H.M., R.L.A.) and Titus Family Department of Clinical Pharmacy and Pharmaceutical Economics and Policy (L.A., D.L.D.), University of Southern California School of Pharmacy, Los Angeles, California; Department of Anesthesia, Beckman Program for Molecular and Genetic Medicine, Stanford University, Stanford University Medical Center, Stanford, California (J.R.T.); Departments of Anesthesiology and Pharmacology and Chemical Biology, University of Pittsburgh, Pittsburgh, Pennsylvania (G.E.H.); and Amgen Inc., Thousand Oaks, California (D.I.P.)
| | - James R Trudell
- Department of Pharmacology and Pharmaceutical Sciences (A.N., K.H.M., R.L.A.) and Titus Family Department of Clinical Pharmacy and Pharmaceutical Economics and Policy (L.A., D.L.D.), University of Southern California School of Pharmacy, Los Angeles, California; Department of Anesthesia, Beckman Program for Molecular and Genetic Medicine, Stanford University, Stanford University Medical Center, Stanford, California (J.R.T.); Departments of Anesthesiology and Pharmacology and Chemical Biology, University of Pittsburgh, Pittsburgh, Pennsylvania (G.E.H.); and Amgen Inc., Thousand Oaks, California (D.I.P.)
| | - Gregg E Homanics
- Department of Pharmacology and Pharmaceutical Sciences (A.N., K.H.M., R.L.A.) and Titus Family Department of Clinical Pharmacy and Pharmaceutical Economics and Policy (L.A., D.L.D.), University of Southern California School of Pharmacy, Los Angeles, California; Department of Anesthesia, Beckman Program for Molecular and Genetic Medicine, Stanford University, Stanford University Medical Center, Stanford, California (J.R.T.); Departments of Anesthesiology and Pharmacology and Chemical Biology, University of Pittsburgh, Pittsburgh, Pennsylvania (G.E.H.); and Amgen Inc., Thousand Oaks, California (D.I.P.)
| | - Daya I Perkins
- Department of Pharmacology and Pharmaceutical Sciences (A.N., K.H.M., R.L.A.) and Titus Family Department of Clinical Pharmacy and Pharmaceutical Economics and Policy (L.A., D.L.D.), University of Southern California School of Pharmacy, Los Angeles, California; Department of Anesthesia, Beckman Program for Molecular and Genetic Medicine, Stanford University, Stanford University Medical Center, Stanford, California (J.R.T.); Departments of Anesthesiology and Pharmacology and Chemical Biology, University of Pittsburgh, Pittsburgh, Pennsylvania (G.E.H.); and Amgen Inc., Thousand Oaks, California (D.I.P.)
| | - Daryl L Davies
- Department of Pharmacology and Pharmaceutical Sciences (A.N., K.H.M., R.L.A.) and Titus Family Department of Clinical Pharmacy and Pharmaceutical Economics and Policy (L.A., D.L.D.), University of Southern California School of Pharmacy, Los Angeles, California; Department of Anesthesia, Beckman Program for Molecular and Genetic Medicine, Stanford University, Stanford University Medical Center, Stanford, California (J.R.T.); Departments of Anesthesiology and Pharmacology and Chemical Biology, University of Pittsburgh, Pittsburgh, Pennsylvania (G.E.H.); and Amgen Inc., Thousand Oaks, California (D.I.P.)
| | - Ronald L Alkana
- Department of Pharmacology and Pharmaceutical Sciences (A.N., K.H.M., R.L.A.) and Titus Family Department of Clinical Pharmacy and Pharmaceutical Economics and Policy (L.A., D.L.D.), University of Southern California School of Pharmacy, Los Angeles, California; Department of Anesthesia, Beckman Program for Molecular and Genetic Medicine, Stanford University, Stanford University Medical Center, Stanford, California (J.R.T.); Departments of Anesthesiology and Pharmacology and Chemical Biology, University of Pittsburgh, Pittsburgh, Pennsylvania (G.E.H.); and Amgen Inc., Thousand Oaks, California (D.I.P.)
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Finegersh A, Homanics GE. Acute ethanol alters multiple histone modifications at model gene promoters in the cerebral cortex. Alcohol Clin Exp Res 2014; 38:1865-73. [PMID: 24942484 DOI: 10.1111/acer.12465] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2013] [Accepted: 04/08/2014] [Indexed: 11/28/2022]
Abstract
BACKGROUND Ethanol (EtOH) exposure alters gene expression in the cerebral cortex (CCx); however, mechanisms of EtOH-induced gene regulation are not well understood. We hypothesized that EtOH regulates gene expression by differentially altering histone modifications at gene promoters that are up- and down-regulated by EtOH. Such epigenetic mechanisms may ultimately contribute to EtOH-induced neuro-adaptations that underlie tolerance, dependence, and EtOH-use disorders. METHODS Eight-week-old, male C57BL/6J mice were treated with 3 g/kg EtOH (intraperitoneally) or saline and sacrificed 6 hours after injection; the CCx and hippocampus (HC) were immediately removed and flash frozen. Chromatin immunoprecipitation was used to study the association of model gene promoters with histone modifications. Western blot was used to detect global changes in the histone modifications studied. We also used a polymerase chain reaction (PCR) array to identify changes in expression of chromatin-modifying enzymes. RESULTS In CCx, acute EtOH decreased expression of Gad1, Hdac2, and Hdac11, which was associated with decreased histone acetylation at the Gad1 and Hdac2 promoters; we also identified increased expression of Mt1, Mt2, Egr1, which was associated with increased H3K4me3 levels at the Mt2 promoter and decreased H3K27me3 levels at the Mt1 promoter. We identified an increase in global levels of H3K4me3 in CCx as well as a global increase in H3K9ac and H3K14ac in HC. The PCR array identified decreased expression of Csrp2 bp, Hdac2, and Hdac11 as well as increased expression of Kat2b in CCx. CONCLUSIONS Acute EtOH induces chromatin remodeling at model up- and down-regulated genes in CCx. Different patterns of histone modifications at these gene promoters indicate that EtOH may be acting through multiple histone-modifying enzymes to alter gene expression; in particular, differential expression of Kat2b, Hdac2, Hdac11, and Csrp2 bp in CCx may mediate EtOH-induced chromatin remodeling. Additional studies are necessary to determine the relationship between EtOH-induced changes in histone-modifying enzymes, specific EtOH-induced histone modifications, and gene expression.
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Affiliation(s)
- Andrey Finegersh
- Departments of Anesthesiology and Pharmacology & Chemical Biology, University of Pittsburgh, Pittsburgh, Pennsylvania
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