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Hitzemann R, Gao L, Fei SS, Ray K, Vigh-Conrad KA, Phillips TJ, Searles R, Cervera-Juanes RP, Khadka R, Carlson TL, Gonzales SW, Newman N, Grant KA. Effects of repeated alcohol abstinence on within-subject prefrontal cortical gene expression in rhesus macaques. ADVANCES IN DRUG AND ALCOHOL RESEARCH 2024; 4:12528. [PMID: 38737578 PMCID: PMC11082748 DOI: 10.3389/adar.2024.12528] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/05/2023] [Accepted: 04/12/2024] [Indexed: 05/14/2024]
Abstract
Male rhesus monkeys (n = 24) had a biopsy of prefrontal cortical area 46 prior to chronic ethanol self-administration (n = 17) or caloric control (n = 7). Fourteen months of daily self-administration (water vs. 4% alcohol, 22 h access/day termed "open-access") was followed by two cycles of prolonged abstinence (5 weeks) each followed by 3 months of open-access alcohol and a final abstinence followed by necropsy. At necropsy, a biopsy of Area 46, contralateral to the original biopsy, was obtained. Gene expression data (RNA-Seq) were collected comparing biopsy/necropsy samples. Monkeys were categorized by drinking status during the final post-abstinent drinking phase as light (LD), binge (BD), heavy (HD) and very heavy (VHD drinkers). Comparing pre-ethanol to post-abstinent biopsies, four animals that converted from HD to VHD status had significant ontology enrichments in downregulated genes (necropsy minus biopsy n = 286) that included immune response (FDR < 9 × 10-7) and plasma membrane changes (FDR < 1 × 10-7). Genes in the immune response category included IL16 and 18, CCR1, B2M, TLR3, 6 and 7, SP2 and CX3CR1. Upregulated genes (N = 388) were particularly enriched in genes associated with the negative regulation of MAP kinase activity (FDR < 3 × 10-5), including DUSP 1, 4, 5, 6 and 18, SPRY 2, 3, and 4, SPRED2, BMP4 and RGS2. Overall, these data illustrate the power of the NHP model and the within-subject design of genomic changes due to alcohol and suggest new targets for treating severe escalated drinking following repeated alcohol abstinence attempts.
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Affiliation(s)
- Robert Hitzemann
- Department of Behavioral Neuroscience, Oregon Health and Science University, Portland, OR, United States
- Portland Alcohol Research Center, Oregon Health and Science University, Portland, OR, United States
- Veterans Affairs Portland Health Care System, Portland, OR, United States
| | - Lina Gao
- Portland Alcohol Research Center, Oregon Health and Science University, Portland, OR, United States
- Bioinformatics and Biostatistics Core, Oregon National Primate Research Center, Oregon Health and Science University, Beaverton, OR, United States
| | - Suzanne S. Fei
- Portland Alcohol Research Center, Oregon Health and Science University, Portland, OR, United States
- Bioinformatics and Biostatistics Core, Oregon National Primate Research Center, Oregon Health and Science University, Beaverton, OR, United States
| | - Karina Ray
- Bioinformatics and Biostatistics Core, Oregon National Primate Research Center, Oregon Health and Science University, Beaverton, OR, United States
| | - Katinka A. Vigh-Conrad
- Division of Genetics, Oregon National Primate Research Center, Oregon Health and Science University, Beaverton, OR, United States
| | - Tamara J. Phillips
- Department of Behavioral Neuroscience, Oregon Health and Science University, Portland, OR, United States
- Portland Alcohol Research Center, Oregon Health and Science University, Portland, OR, United States
- Veterans Affairs Portland Health Care System, Portland, OR, United States
| | - Robert Searles
- Portland Alcohol Research Center, Oregon Health and Science University, Portland, OR, United States
- Integrated Genomics Laboratory, Oregon Health and Science University, Portland, OR, United States
| | - Rita P. Cervera-Juanes
- Division of Neuroscience, Oregon National Primate Research Center, Oregon Health and Science University, Beaverton, OR, United States
| | - Rupak Khadka
- Division of Neuroscience, Oregon National Primate Research Center, Oregon Health and Science University, Beaverton, OR, United States
| | - Timothy L. Carlson
- Division of Neuroscience, Oregon National Primate Research Center, Oregon Health and Science University, Beaverton, OR, United States
| | - Steven W. Gonzales
- Division of Neuroscience, Oregon National Primate Research Center, Oregon Health and Science University, Beaverton, OR, United States
| | - Natali Newman
- Division of Neuroscience, Oregon National Primate Research Center, Oregon Health and Science University, Beaverton, OR, United States
| | - Kathleen A. Grant
- Department of Behavioral Neuroscience, Oregon Health and Science University, Portland, OR, United States
- Portland Alcohol Research Center, Oregon Health and Science University, Portland, OR, United States
- Division of Neuroscience, Oregon National Primate Research Center, Oregon Health and Science University, Beaverton, OR, United States
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2
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Hitzemann R, Ozburn AR, Lockwood D, Phillips TJ. Modeling Brain Gene Expression in Alcohol Use Disorder with Genetic Animal Models. Curr Top Behav Neurosci 2023. [PMID: 37982929 DOI: 10.1007/7854_2023_455] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2023]
Abstract
Animal genetic models have and will continue to provide important new information about the behavioral and physiological adaptations associated with alcohol use disorder (AUD). This chapter focuses on two models, ethanol preference and drinking in the dark (DID), their usefulness in interrogating brain gene expression data and the relevance of the data obtained to interpret AUD-related GWAS and TWAS studies. Both the animal and human data point to the importance for AUD of changes in synaptic transmission (particularly glutamate and GABA transmission), of changes in the extracellular matrix (specifically including collagens, cadherins and protocadherins) and of changes in neuroimmune processes. The implementation of new technologies (e.g., cell type-specific gene expression) is expected to further enhance the value of genetic animal models in understanding AUD.
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Affiliation(s)
- Robert Hitzemann
- Department of Behavioral Neuroscience, Portland Alcohol Research Center, Oregon Health and Science University, Portland, OR, USA.
| | - Angela R Ozburn
- Department of Behavioral Neuroscience, Portland Alcohol Research Center, Oregon Health and Science University, Portland, OR, USA
| | - Denesa Lockwood
- Department of Behavioral Neuroscience, Portland Alcohol Research Center, Oregon Health and Science University, Portland, OR, USA
| | - Tamara J Phillips
- Department of Behavioral Neuroscience, Portland Alcohol Research Center, Oregon Health and Science University, Portland, OR, USA
- Veterans Affairs Portland Health Care System, Portland, OR, USA
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3
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Anderson JQ, Darakjian P, Hitzemann R, Lockwood DR, Phillips TJ, Ozburn AR. Brain gene expression differences related to ethanol preference in the collaborative cross founder strains. Front Behav Neurosci 2022; 16:992727. [PMID: 36212197 PMCID: PMC9539754 DOI: 10.3389/fnbeh.2022.992727] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2022] [Accepted: 08/30/2022] [Indexed: 11/26/2022] Open
Abstract
The collaborative cross (CC) founder strains include five classical inbred laboratory strains [129S1/SvlmJ (S129), A/J (AJ), C57BL/6J (B6), NOD/ShiLtJ (NOD), and NZO/HILtJ (NZO)] and three wild-derived strains [CAST/EiJ (CAST), PWK/PhJ (PWK), and WSB/EiJ (WSB)]. These strains encompass 89% of the genetic diversity available in Mus musculus and ∼10-20 times more genetic diversity than found in Homo sapiens. For more than 60 years the B6 strain has been widely used as a genetic model for high ethanol preference and consumption. However, another of the CC founder strains, PWK, has been identified as a high ethanol preference/high consumption strain. The current study determined how the transcriptomes of the B6 and PWK strains differed from the 6 low preference CC strains across 3 nodes of the brain addiction circuit. RNA-Seq data were collected from the central nucleus of the amygdala (CeA), the nucleus accumbens core (NAcc) and the prelimbic cortex (PrL). Differential expression (DE) analysis was performed in each of these brain regions for all 28 possible pairwise comparisons of the CC founder strains. Unique genes for each strain were identified by selecting for genes that differed significantly [false discovery rate (FDR) < 0.05] from all other strains in the same direction. B6 was identified as the most distinct classical inbred laboratory strain, having the highest number of total differently expressed genes (DEGs) and DEGs with high log fold change, and unique genes compared to other CC strains. Less than 50 unique DEGs were identified in common between B6 and PWK within all three brain regions, indicating the strains potentially represent two distinct genetic signatures for risk for high ethanol-preference. 338 DEGs were found to be commonly different between B6, PWK and the average expression of the remaining CC strains within all three regions. The commonly different up-expressed genes were significantly enriched (FDR < 0.001) among genes associated with neuroimmune function. These data compliment findings showing that neuroimmune signaling is key to understanding alcohol use disorder (AUD) and support use of these 8 strains and the highly heterogeneous mouse populations derived from them to identify alcohol-related brain mechanisms and treatment targets.
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Affiliation(s)
- Justin Q. Anderson
- Department of Behavioral Neuroscience, Portland Alcohol Research Center, Oregon Health and Science University, Portland, OR, United States
- VA Portland Health Care System, Portland, OR, United States
| | - Priscila Darakjian
- Department of Behavioral Neuroscience, Portland Alcohol Research Center, Oregon Health and Science University, Portland, OR, United States
- VA Portland Health Care System, Portland, OR, United States
| | - Robert Hitzemann
- Department of Behavioral Neuroscience, Portland Alcohol Research Center, Oregon Health and Science University, Portland, OR, United States
- VA Portland Health Care System, Portland, OR, United States
| | - Denesa R. Lockwood
- Department of Behavioral Neuroscience, Portland Alcohol Research Center, Oregon Health and Science University, Portland, OR, United States
- VA Portland Health Care System, Portland, OR, United States
| | - Tamara J. Phillips
- Department of Behavioral Neuroscience, Portland Alcohol Research Center, Oregon Health and Science University, Portland, OR, United States
- VA Portland Health Care System, Portland, OR, United States
| | - Angela R. Ozburn
- Department of Behavioral Neuroscience, Portland Alcohol Research Center, Oregon Health and Science University, Portland, OR, United States
- VA Portland Health Care System, Portland, OR, United States
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Parker CC, Philip VM, Gatti DM, Kasparek S, Kreuzman AM, Kuffler L, Mansky B, Masneuf S, Sharif K, Sluys E, Taterra D, Taylor WM, Thomas M, Polesskaya O, Palmer AA, Holmes A, Chesler EJ. Genome-wide association mapping of ethanol sensitivity in the Diversity Outbred mouse population. Alcohol Clin Exp Res 2022; 46:941-960. [PMID: 35383961 DOI: 10.1111/acer.14825] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2021] [Revised: 03/04/2022] [Accepted: 03/30/2022] [Indexed: 12/01/2022]
Abstract
BACKGROUND A strong predictor for the development of alcohol use disorder (AUD) is altered sensitivity to the intoxicating effects of alcohol. Individual differences in the initial sensitivity to alcohol are controlled in part by genetic factors. Mice offer a powerful tool to elucidate the genetic basis of behavioral and physiological traits relevant to AUD, but conventional experimental crosses have only been able to identify large chromosomal regions rather than specific genes. Genetically diverse, highly recombinant mouse populations make it possible to observe a wider range of phenotypic variation, offer greater mapping precision, and thus increase the potential for efficient gene identification. METHODS We have taken advantage of the Diversity Outbred (DO) mouse population to identify and precisely map quantitative trait loci (QTL) associated with ethanol sensitivity. We phenotyped 798 male J:DO mice for three measures of ethanol sensitivity: ataxia, hypothermia, and loss of the righting response. We used high-density MegaMUGA and GigaMUGA to obtain genotypes ranging from 77,808 to 143,259 SNPs. We also performed RNA sequencing in striatum to map expression QTLs and identify gene expression-trait correlations. We then applied a systems genetic strategy to identify narrow QTLs and construct the network of correlations that exists between DNA sequence, gene expression values, and ethanol-related phenotypes to prioritize our list of positional candidate genes. RESULTS We observed large amounts of phenotypic variation with the DO population and identified suggestive and significant QTLs associated with ethanol sensitivity on chromosomes 1, 2, and 16. The implicated regions were narrow (4.5-6.9 Mb in size) and each QTL explained ~4-5% of the variance. CONCLUSIONS Our results can be used to identify alleles that contribute to AUD in humans, elucidate causative biological mechanisms, or assist in the development of novel therapeutic interventions.
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Affiliation(s)
- Clarissa C Parker
- Department of Psychology and Program in Neuroscience, Middlebury College, Middlebury, Vermont, USA
| | - Vivek M Philip
- Center for Computational Sciences, The Jackson Laboratory, Bar Harbor, Maine, USA
| | - Daniel M Gatti
- Center for Computational Sciences, The Jackson Laboratory, Bar Harbor, Maine, USA
| | - Steven Kasparek
- Department of Psychology and Program in Neuroscience, Middlebury College, Middlebury, Vermont, USA
| | - Andrew M Kreuzman
- Department of Psychology and Program in Neuroscience, Middlebury College, Middlebury, Vermont, USA
| | - Lauren Kuffler
- Center for Mammalian Genetics, The Jackson Laboratory, Bar Harbor, Maine, USA
| | - Benjamin Mansky
- Department of Psychology and Program in Neuroscience, Middlebury College, Middlebury, Vermont, USA
| | - Sophie Masneuf
- Laboratory of Behavioral and Genomic Neuroscience, NIAAA, NIH, Rockville, MD, USA
| | - Kayvon Sharif
- Department of Psychology and Program in Neuroscience, Middlebury College, Middlebury, Vermont, USA
| | - Erica Sluys
- Laboratory of Behavioral and Genomic Neuroscience, NIAAA, NIH, Rockville, MD, USA
| | - Dominik Taterra
- Department of Psychology and Program in Neuroscience, Middlebury College, Middlebury, Vermont, USA
| | - Walter M Taylor
- Department of Psychology and Program in Neuroscience, Middlebury College, Middlebury, Vermont, USA
| | - Mary Thomas
- Department of Psychology and Program in Neuroscience, Middlebury College, Middlebury, Vermont, USA
| | - Oksana Polesskaya
- Department of Psychiatry, University of California San Diego, La Jolla, California, USA.,Institute for Genomic Medicine, University of California San Diego, La Jolla, California, USA
| | - Abraham A Palmer
- Department of Psychiatry, University of California San Diego, La Jolla, California, USA.,Institute for Genomic Medicine, University of California San Diego, La Jolla, California, USA
| | - Andrew Holmes
- Laboratory of Behavioral and Genomic Neuroscience, NIAAA, NIH, Rockville, MD, USA
| | - Elissa J Chesler
- Center for Mammalian Genetics, The Jackson Laboratory, Bar Harbor, Maine, USA
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Moderate Folic Acid Supplementation in Pregnant Mice Results in Altered Sex-Specific Gene Expression in Brain of Young Mice and Embryos. Nutrients 2022; 14:nu14051051. [PMID: 35268026 PMCID: PMC8912750 DOI: 10.3390/nu14051051] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2022] [Revised: 02/22/2022] [Accepted: 02/26/2022] [Indexed: 02/07/2023] Open
Abstract
Food fortification and increased vitamin intake have led to higher folic acid (FA) consumption by many pregnant women. We showed that FA-supplemented diet in pregnant mice (fivefold higher FA than the recommended level (5xFASD)) led to hyperactivity-like behavior and memory impairment in pups. Disturbed choline/methyl metabolism and altered placental gene expression were identified. The aim of this study was to examine the impact of 5xFASD on the brain at two developmental stages, postnatal day (P) 30 and embryonic day (E) 17.5. Female C57BL/6 mice were fed a control diet or 5xFASD for 1 month before mating. Diets were maintained throughout the pregnancy and lactation until P30 or during pregnancy until E17.5. The 5xFASD led to sex-specific transcription changes in P30 cerebral cortex and E17.5 cerebrum, with microarrays showing a total of 1003 and 623 changes, respectively. Enhanced mRNA degradation was observed in E17.5 cerebrum. Expression changes of genes involved in neurotransmission, neuronal growth and development, and angiogenesis were verified by qRT-PCR; 12 and 15 genes were verified at P30 and E17.5, respectively. Hippocampal collagen staining suggested decreased vessel density in FASD male embryos. This study provides insight into the mechanisms of neurobehavioral alterations and highlights potential deleterious consequences of moderate folate oversupplementation during pregnancy.
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Hitzemann R, Lockwood DR, Ozburn AR, Phillips TJ. On the Use of Heterogeneous Stock Mice to Map Transcriptomes Associated With Excessive Ethanol Consumption. Front Psychiatry 2021; 12:725819. [PMID: 34712155 PMCID: PMC8545898 DOI: 10.3389/fpsyt.2021.725819] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/15/2021] [Accepted: 08/30/2021] [Indexed: 01/11/2023] Open
Abstract
We and many others have noted the advantages of using heterogeneous (HS) animals to map genes and gene networks associated with both behavioral and non-behavioral phenotypes. Importantly, genetically complex Mus musculus crosses provide substantially increased resolution to examine old and new relationships between gene expression and behavior. Here we report on data obtained from two HS populations: the HS/NPT derived from eight inbred laboratory mouse strains and the HS-CC derived from the eight collaborative cross inbred mouse strains that includes three wild-derived strains. Our work has focused on the genes and gene networks associated with risk for excessive ethanol consumption, individual variation in ethanol consumption and the consequences, including escalation, of long-term ethanol consumption. Background data on the development of HS mice is provided, including advantages for the detection of expression quantitative trait loci. Examples are also provided of using HS animals to probe the genes associated with ethanol preference and binge ethanol consumption.
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Affiliation(s)
- Robert Hitzemann
- Department of Behavioral Neuroscience and Portland Alcohol Research Center, Oregon Health & Science University, Portland, OR, United States
| | - Denesa R. Lockwood
- Department of Behavioral Neuroscience and Portland Alcohol Research Center, Oregon Health & Science University, Portland, OR, United States
| | - Angela R. Ozburn
- Department of Behavioral Neuroscience and Portland Alcohol Research Center, Oregon Health & Science University, Portland, OR, United States
- Veterans Affairs Portland Health Care System, Portland, OR, United States
| | - Tamara J. Phillips
- Department of Behavioral Neuroscience and Portland Alcohol Research Center, Oregon Health & Science University, Portland, OR, United States
- Veterans Affairs Portland Health Care System, Portland, OR, United States
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7
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Walter N, Cervera-Juanes R, Zheng C, Darakjian P, Lockwood D, Cuzon-Carlson V, Ray K, Fei S, Conrad D, Searles R, Grant K, Hitzemann R. Effect of chronic ethanol consumption in rhesus macaques on the nucleus accumbens core transcriptome. Addict Biol 2021; 26:e13021. [PMID: 33942443 PMCID: PMC8588809 DOI: 10.1111/adb.13021] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2020] [Revised: 01/15/2021] [Accepted: 01/19/2021] [Indexed: 12/13/2022]
Abstract
The nucleus accumbens core (NAcc) has been repeatedly demonstrated to be a key component of the circuitry associated with excessive ethanol consumption. Previous studies have illustrated that in a nonhuman primate (NHP) model of chronic ethanol consumption, there is significant epigenetic remodeling of the NAcc. In the current study, RNA-Seq was used to examine genome-wide gene expression in eight each of control, low/binge (LD*), and high/very high (HD*) rhesus macaque drinkers. Using an FDR < 0.05, zero genes were significantly differentially expressed (DE) between LD* and controls, six genes between HD* and LD*, and 734 genes between HD* and controls. Focusing on HD* versus control DE genes, the upregulated genes (N = 366) were enriched in genes with annotations associated with signal recognition particle (SRP)-dependent co-translational protein targeting to membrane (FDR < 3 × 10-59 ), structural constituent of ribosome (FDR < 3 × 10-47 ), and ribosomal subunit (FDR < 5 × 10-48 ). Downregulated genes (N = 363) were enriched in annotations associated with behavior (FDR < 2 × 10-4 ), membrane organization (FDR < 1 × 10-4 ), inorganic cation transmembrane transporter activity (FDR < 2 × 10-3 ), synapse part (FDR < 4 × 10-10 ), glutamatergic synapse (FDR < 1 × 10-6 ), and GABAergic synapse (FDR < 6 × 10-4 ). Ingenuity Pathway Analysis (IPA) revealed that EIF2 signaling and mTOR pathways were significantly upregulated in HD* animals (FDR < 3 × 10-33 and <2 × 10-16 , respectively). Overall, the data supported our working hypothesis; excessive consumption would be associated with transcriptional differences in GABA/glutamate-related genes.
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Affiliation(s)
- Nicole Walter
- Division of Neuroscience, Oregon National Primate Research Center, Oregon Health & Science University, Portland, Oregon, USA
| | - Rita Cervera-Juanes
- Division of Genetics, Oregon National Primate Research Center, Oregon Health & Science University, Portland, Oregon, USA
| | - Christina Zheng
- Knight Cancer Institute, Oregon Health & Science University, Portland, Oregon, USA
| | - Priscila Darakjian
- Division of Genetics, Oregon National Primate Research Center, Oregon Health & Science University, Portland, Oregon, USA
- Department of Behavioral Neuroscience, Oregon Health & Science University, Portland, Oregon, USA
| | - Denesa Lockwood
- Department of Behavioral Neuroscience, Oregon Health & Science University, Portland, Oregon, USA
| | - Verginia Cuzon-Carlson
- Division of Neuroscience, Oregon National Primate Research Center, Oregon Health & Science University, Portland, Oregon, USA
| | - Karina Ray
- Division of Genetics, Oregon National Primate Research Center, Oregon Health & Science University, Portland, Oregon, USA
| | - Suzanne Fei
- Division of Genetics, Oregon National Primate Research Center, Oregon Health & Science University, Portland, Oregon, USA
| | - Don Conrad
- Division of Genetics, Oregon National Primate Research Center, Oregon Health & Science University, Portland, Oregon, USA
| | - Robert Searles
- Integrated Genomics Laboratory, Oregon Health & Science University, Portland, Oregon, USA
| | - Kathleen Grant
- Division of Neuroscience, Oregon National Primate Research Center, Oregon Health & Science University, Portland, Oregon, USA
- Department of Behavioral Neuroscience, Oregon Health & Science University, Portland, Oregon, USA
| | - Robert Hitzemann
- Department of Behavioral Neuroscience, Oregon Health & Science University, Portland, Oregon, USA
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8
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Kisby BR, Farris SP, McManus MM, Varodayan FP, Roberto M, Harris RA, Ponomarev I. Alcohol Dependence in Rats Is Associated with Global Changes in Gene Expression in the Central Amygdala. Brain Sci 2021; 11:brainsci11091149. [PMID: 34573170 PMCID: PMC8468792 DOI: 10.3390/brainsci11091149] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2020] [Revised: 08/06/2021] [Accepted: 08/21/2021] [Indexed: 12/20/2022] Open
Abstract
Alcohol dependence is associated with adverse consequences of alcohol (ethanol) use and is evident in most severe cases of alcohol use disorder (AUD). The central nucleus of the amygdala (CeA) plays a critical role in the development of alcohol dependence and escalation of alcohol consumption in dependent subjects. Molecular mechanisms underlying the CeA-driven behavioral changes are not well understood. Here, we examined the effects of alcohol on global gene expression in the CeA using a chronic intermittent ethanol (CIE) vapor model in rats and RNA sequencing (RNA-Seq). The CIE procedure resulted in robust changes in CeA gene expression during intoxication, as the number of differentially expressed genes (DEGs) was significantly greater than those expected by chance. Over-representation analysis of cell types, functional groups and molecular pathways revealed biological categories potentially important for the development of alcohol dependence in our model. Genes specific for astrocytes, myelinating oligodendrocytes, and endothelial cells were over-represented in the DEG category, suggesting that these cell types were particularly affected by the CIE procedure. The majority of the over-represented functional groups and molecular pathways were directly related to the functions of glial and endothelial cells, including extracellular matrix (ECM) organization, myelination, and the regulation of innate immune response. A coordinated regulation of several ECM metalloproteinases (e.g., Mmp2; Mmp14), their substrates (e.g., multiple collagen genes and myelin basic protein; Mbp), and a metalloproteinase inhibitor, Reck, suggests a specific mechanism for ECM re-organization in response to chronic alcohol, which may modulate neuronal activity and result in behavioral changes, such as an escalation of alcohol drinking. Our results highlight the importance of glial and endothelial cells in the effects of chronic alcohol exposure on the CeA, and demonstrate further insight into the molecular mechanisms of alcohol dependence in rats. These molecular targets may be used in future studies to develop therapeutics to treat AUD.
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Affiliation(s)
- Brent R. Kisby
- Department of Pharmacology and Neuroscience, Texas Tech University Health Sciences Center, Lubbock, TX 79430, USA; (B.R.K.); (M.M.M.)
| | - Sean P. Farris
- Department of Neuroscience, University of Texas at Austin, Austin, TX 78715, USA; (S.P.F.); (R.A.H.)
- Department of Anesthesiology and Perioperative Medicine, University of Pittsburgh, Pittsburgh, PA 15261, USA
- Department of Biomedical Informatics, University of Pittsburgh, Pittsburgh, PA 15206, USA
| | - Michelle M. McManus
- Department of Pharmacology and Neuroscience, Texas Tech University Health Sciences Center, Lubbock, TX 79430, USA; (B.R.K.); (M.M.M.)
| | - Florence P. Varodayan
- Department of Psychology, Binghamton University-SUNY, Binghamton, NY 13902, USA;
- Department of Molecular Medicine, The Scripps Research Institute, La Jolla, CA 92037, USA;
| | - Marisa Roberto
- Department of Molecular Medicine, The Scripps Research Institute, La Jolla, CA 92037, USA;
| | - R. Adron Harris
- Department of Neuroscience, University of Texas at Austin, Austin, TX 78715, USA; (S.P.F.); (R.A.H.)
- Waggoner Center for Alcohol and Addiction Research, University of Texas at Austin, Austin, TX 78741, USA
| | - Igor Ponomarev
- Department of Pharmacology and Neuroscience, Texas Tech University Health Sciences Center, Lubbock, TX 79430, USA; (B.R.K.); (M.M.M.)
- Correspondence:
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9
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Rao X, Thapa KS, Chen AB, Lin H, Gao H, Reiter JL, Hargreaves KA, Ipe J, Lai D, Xuei X, Wang Y, Gu H, Kapoor M, Farris SP, Tischfield J, Foroud T, Goate AM, Skaar TC, Mayfield RD, Edenberg HJ, Liu Y. Allele-specific expression and high-throughput reporter assay reveal functional genetic variants associated with alcohol use disorders. Mol Psychiatry 2021; 26:1142-1151. [PMID: 31477794 PMCID: PMC7050407 DOI: 10.1038/s41380-019-0508-z] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/21/2019] [Revised: 07/09/2019] [Accepted: 07/24/2019] [Indexed: 11/15/2022]
Abstract
Genome-wide association studies (GWAS) of complex traits, such as alcohol use disorders (AUD), usually identify variants in non-coding regions and cannot by themselves distinguish whether the associated variants are functional or in linkage disequilibrium with the functional variants. Transcriptome studies can identify genes whose expression differs between alcoholics and controls. To test which variants associated with AUD may cause expression differences, we integrated data from deep RNA-seq and GWAS of four postmortem brain regions from 30 subjects with AUD and 30 controls to analyze allele-specific expression (ASE). We identified 88 genes with differential ASE in subjects with AUD compared to controls. Next, to test one potential mechanism contributing to the differential ASE, we analyzed single nucleotide polymorphisms (SNPs) in the 3' untranslated regions (3'UTR) of these genes. Of the 88 genes with differential ASE, 61 genes contained 437 SNPs in the 3'UTR with at least one heterozygote among the subjects studied. Using a modified PASSPORT-seq (parallel assessment of polymorphisms in miRNA target-sites by sequencing) assay, we identified 25 SNPs that affected RNA levels in a consistent manner in two neuroblastoma cell lines, SH-SY5Y and SK-N-BE(2). Many of these SNPs are in binding sites of miRNAs and RNA-binding proteins, indicating that these SNPs are likely causal variants of AUD-associated differential ASE. In sum, we demonstrate that a combination of computational and experimental approaches provides a powerful strategy to uncover functionally relevant variants associated with the risk for AUD.
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Affiliation(s)
- Xi Rao
- Department of Medical & Molecular Genetics, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Kriti S Thapa
- Department of Biochemistry & Molecular Biology, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Andy B Chen
- Department of Medical & Molecular Genetics, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Hai Lin
- Department of Medical & Molecular Genetics, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Hongyu Gao
- Department of Medical & Molecular Genetics, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Jill L Reiter
- Department of Medical & Molecular Genetics, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Katherine A Hargreaves
- Division of Clinical Pharmacology, Department of Medicine, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Joseph Ipe
- Division of Clinical Pharmacology, Department of Medicine, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Dongbing Lai
- Department of Medical & Molecular Genetics, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Xiaoling Xuei
- Department of Medical & Molecular Genetics, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Yue Wang
- Department of Medical & Molecular Genetics, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Hongmei Gu
- Department of Biochemistry & Molecular Biology, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Manav Kapoor
- Ronald M. Loeb Center for Alzheimer's Disease, Department of Neuroscience, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Sean P Farris
- Waggoner Center for Alcohol and Addiction Research, University of Texas at Austin, Austin, TX, USA
| | - Jay Tischfield
- Department of Genetics, Rutgers University, Piscataway, NJ, USA
| | - Tatiana Foroud
- Department of Medical & Molecular Genetics, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Alison M Goate
- Ronald M. Loeb Center for Alzheimer's Disease, Department of Neuroscience, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Todd C Skaar
- Division of Clinical Pharmacology, Department of Medicine, Indiana University School of Medicine, Indianapolis, IN, USA
| | - R Dayne Mayfield
- Waggoner Center for Alcohol and Addiction Research, University of Texas at Austin, Austin, TX, USA
| | - Howard J Edenberg
- Department of Medical & Molecular Genetics, Indiana University School of Medicine, Indianapolis, IN, USA
- Department of Biochemistry & Molecular Biology, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Yunlong Liu
- Department of Medical & Molecular Genetics, Indiana University School of Medicine, Indianapolis, IN, USA.
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10
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Bagley JR, Chesler EJ, Philip VM, Jentsch JD. Heritability of ethanol consumption and pharmacokinetics in a genetically diverse panel of collaborative cross mouse strains and their inbred founders. Alcohol Clin Exp Res 2021; 45:697-708. [PMID: 33619752 PMCID: PMC8441258 DOI: 10.1111/acer.14582] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2020] [Revised: 02/06/2021] [Accepted: 02/12/2021] [Indexed: 12/17/2022]
Abstract
BACKGROUND Interindividual variation in voluntary ethanol consumption and ethanol response is partially influenced by genetic variation. Discovery of the genes and allelic variants that affect these phenotypes may clarify the etiology and pathophysiology of problematic alcohol use, including alcohol use disorder. Genetically diverse mouse populations, which demonstrate heritable variation in ethanol consumption, can be utilized to discover the genes and gene networks that influence this trait. The Collaborative Cross (CC) recombinant inbred strains, Diversity Outbred (DO) population and their 8 founder strains are complementary mouse resources that capture substantial genetic diversity and can demonstrate expansive phenotypic variation in heritable traits. These populations may be utilized to discover candidate genes and gene networks that moderate ethanol consumption and other ethanol-related traits. METHODS We characterized ethanol consumption, preference, and pharmacokinetics in the 8 founder strains and 10 CC strains in 12-hour drinking sessions during the dark phase of the circadian cycle. RESULTS Ethanol consumption was substantially heritable, both early in ethanol access and over a chronic intermittent access schedule. Ethanol pharmacokinetics were also heritable; however, no association between strain-level ethanol consumption and pharmacokinetics was detected. The PWK/PhJ strain was the highest drinking strain, with consumption substantially exceeding that of the C57BL/6J strain, which is commonly used as a model of "high" or "binge" drinking. Notably, we found strong evidence that sex moderated genetic effects on voluntary ethanol drinking. CONCLUSIONS Collectively, this research serves as a foundation for expanded genetic study of ethanol consumption in the CC/DO and related populations. Moreover, we identified reference strains with extreme consumption phenotypes that effectively represent polygenic models of excessive ethanol use.
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Affiliation(s)
- Jared R Bagley
- Department of Psychology, Binghamton University, Binghamton, NY, USA
| | - Elissa J Chesler
- The Jackson Laboratory for Mammalian Genetics, Bar Harbor, ME, USA
| | - Vivek M Philip
- The Jackson Laboratory for Mammalian Genetics, Bar Harbor, ME, USA
| | - James D Jentsch
- Department of Psychology, Binghamton University, Binghamton, NY, USA
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11
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Hitzemann R, Phillips TJ, Lockwood DR, Darakjian P, Searles RP. Phenotypic and gene expression features associated with variation in chronic ethanol consumption in heterogeneous stock collaborative cross mice. Genomics 2020; 112:4516-4524. [PMID: 32771621 PMCID: PMC7749084 DOI: 10.1016/j.ygeno.2020.08.004] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2020] [Revised: 07/22/2020] [Accepted: 08/04/2020] [Indexed: 12/12/2022]
Abstract
Of the more than 100 studies that have examined relationships between excessive ethanol consumption and the brain transcriptome, few rodent studies have examined chronic consumption. Heterogeneous stock collaborative cross mice freely consumed ethanol vs. water for 3 months. Transcriptional differences were examined for the central nucleus of the amygdala, a brain region known to impact ethanol preference. Early preference was modestly predictive of final preference and there was significant escalation of preference in females only. Genes significantly correlated with female preference were enriched in annotations for the primary cilium and extracellular matrix. A single module in the gene co-expression network was enriched in genes with an astrocyte annotation. The key hub node was the master regulator, orthodenticle homeobox 2 (Otx2). These data support an important role for the extracellular matrix, primary cilium and astrocytes in ethanol preference and consumption differences among individual female mice of a genetically diverse population.
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Affiliation(s)
- Robert Hitzemann
- Department of Behavioral Neuroscience, Oregon Health & Science University, Portland, OR 97239, USA; Portland Alcohol Research Center, Oregon Health & Science University, Portland, OR 97239, USA.
| | - Tamara J Phillips
- Department of Behavioral Neuroscience, Oregon Health & Science University, Portland, OR 97239, USA; Portland Alcohol Research Center, Oregon Health & Science University, Portland, OR 97239, USA; Veterans Affairs Portland Health Care System, Portland, OR 97239, USA.
| | - Denesa R Lockwood
- Department of Behavioral Neuroscience, Oregon Health & Science University, Portland, OR 97239, USA; Portland Alcohol Research Center, Oregon Health & Science University, Portland, OR 97239, USA.
| | - Priscila Darakjian
- Department of Behavioral Neuroscience, Oregon Health & Science University, Portland, OR 97239, USA; Portland Alcohol Research Center, Oregon Health & Science University, Portland, OR 97239, USA.
| | - Robert P Searles
- Portland Alcohol Research Center, Oregon Health & Science University, Portland, OR 97239, USA; Integrated Genomics Laboratory, Oregon Health & Science University, Portland, OR 97239, USA.
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12
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Powers KG, Ma XM, Eipper BA, Mains RE. Cell-type specific knockout of peptidylglycine α-amidating monooxygenase reveals specific behavioral roles in excitatory forebrain neurons and cardiomyocytes. GENES BRAIN AND BEHAVIOR 2020; 20:e12699. [PMID: 32902163 DOI: 10.1111/gbb.12699] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/04/2020] [Revised: 09/05/2020] [Accepted: 09/07/2020] [Indexed: 01/11/2023]
Abstract
Neuropeptides and peptide hormones play a crucial role in integrating the many factors that affect physiologic and cognitive processes. The potency of many of these peptides requires an amidated amino acid at the C-terminus; a single enzyme, peptidylglycine α-amidating monooxygenase (PAM), catalyzes this modification. Anxiety-like behavior is known to be altered in mice with a single functional Pam allele (Pam+/- ) and in mice unable to express Pam in excitatory forebrain neurons (PamEmx1-cKO/cKO ) or in cardiomyocytes (PamMyh6-cKO/cKO ). Examination of PAM-positive and glutamic acid decarboxylase 67 (GAD)-positive cells in the amygdala of PamEmx1-cKO/cKO mice demonstrated the absence of PAM in pyramidal neurons and its continued presence in GAD-positive interneurons, suggestive of altered excitatory/inhibitory balance. Additional behavioral tests were used to search for functional alterations in these cell-type specific knockout mice. PamEmx1-cKO/cKO mice exhibited a less focused search pattern for the Barnes Maze escape hole than control or PamMyh6-cKO/cKO mice. While wildtype mice favor interacting with novel objects as opposed to familiar objects, both PamEmx1-cKO/cKO and PamMyh6-cKO/cKO mice exhibited significantly less interest in the novel object. Since PAM levels in the central nervous system of PamMyh6-cKO/cKO mice are unaltered, the behavioral effect observed in these mice may reflect their inability to produce atrial granules and the resulting reduction in serum levels of atrial natriuretic peptide. In the sociability test, male mice of all three genotypes spent more time with same-sex stranger mice; while control females showed no preference for stranger mice, female PamEmx1-cKO/cKO mice showed preference for same-sex stranger mice in all trials.
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Affiliation(s)
- Kathryn G Powers
- Department of Neuroscience, University of Connecticut Health Center, Farmington, Connecticut, USA
| | - Xin-Ming Ma
- Department of Neuroscience, University of Connecticut Health Center, Farmington, Connecticut, USA
| | - Betty A Eipper
- Department of Neuroscience, University of Connecticut Health Center, Farmington, Connecticut, USA
| | - Richard E Mains
- Department of Neuroscience, University of Connecticut Health Center, Farmington, Connecticut, USA
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13
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Kozell LB, Lockwood D, Darakjian P, Edmunds S, Shepherdson K, Buck KJ, Hitzemann R. RNA-Seq Analysis of Genetic and Transcriptome Network Effects of Dual-Trait Selection for Ethanol Preference and Withdrawal Using SOT and NOT Genetic Models. Alcohol Clin Exp Res 2020; 44:820-830. [PMID: 32090358 PMCID: PMC7169974 DOI: 10.1111/acer.14312] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2019] [Accepted: 02/13/2020] [Indexed: 12/16/2022]
Abstract
BACKGROUND Genetic factors significantly affect alcohol consumption and vulnerability to withdrawal. Furthermore, some genetic models showing predisposition to severe withdrawal are also predisposed to low ethanol (EtOH) consumption and vice versa, even when tested independently in naïve animals. METHODS Beginning with a C57BL/6J × DBA/2J F2 intercross founder population, animals were simultaneously selectively bred for both high alcohol consumption and low acute withdrawal (SOT line), or vice versa (NOT line). Using randomly chosen fourth selected generation (S4) mice (N = 18-22/sex/line), RNA-Seq was employed to assess genome-wide gene expression in ventral striatum. The MegaMUGA array was used to detect genome-wide genotypic differences. Differential gene expression and the weighted gene co-expression network analysis were implemented as described elsewhere (Genes Brain Behav 16, 2017, 462). RESULTS The new selection of the SOT and NOT lines was similar to that reported previously (Alcohol Clin Exp Res 38, 2014, 2915). One thousand eight hundred and sixteen transcripts were detected as differentially expressed between the lines. For genes more highly expressed in the SOT line, there was enrichment in genes associated with cell adhesion, synapse organization, and postsynaptic membrane. The genes with a cell adhesion annotation included 23 protocadherins, Mpdz and Dlg2. Genes with a postsynaptic membrane annotation included Gabrb3, Gphn, Grid1, Grin2b, Grin2c, and Grm3. The genes more highly expressed in the NOT line were enriched in a network module (red) with annotations associated with mitochondrial function. Several of these genes were module hub nodes, and these included Nedd8, Guk1, Elof1, Ndufa8, and Atp6v1f. CONCLUSIONS Marked effects of selection on gene expression were detected. The NOT line was characterized by higher expression of hub nodes associated with mitochondrial function. Genes more highly expressed in the SOT aligned with previous findings, for example, Colville and colleagues (Genes Brain Behav 16, 2017, 462) that both high EtOH preference and consumption are associated with effects on cell adhesion and glutamate synaptic plasticity.
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Affiliation(s)
- Laura B Kozell
- From the, Department of Behavioral Neuroscience, VA Portland Health Care System, Oregon Health & Science University, Portland, Oregon
| | - Denesa Lockwood
- From the, Department of Behavioral Neuroscience, VA Portland Health Care System, Oregon Health & Science University, Portland, Oregon
| | - Priscila Darakjian
- From the, Department of Behavioral Neuroscience, VA Portland Health Care System, Oregon Health & Science University, Portland, Oregon
| | - Stephanie Edmunds
- From the, Department of Behavioral Neuroscience, VA Portland Health Care System, Oregon Health & Science University, Portland, Oregon
| | - Karen Shepherdson
- From the, Department of Behavioral Neuroscience, VA Portland Health Care System, Oregon Health & Science University, Portland, Oregon
| | - Kari J Buck
- From the, Department of Behavioral Neuroscience, VA Portland Health Care System, Oregon Health & Science University, Portland, Oregon
| | - Robert Hitzemann
- From the, Department of Behavioral Neuroscience, VA Portland Health Care System, Oregon Health & Science University, Portland, Oregon
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14
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Regional Analysis of the Brain Transcriptome in Mice Bred for High and Low Methamphetamine Consumption. Brain Sci 2019; 9:brainsci9070155. [PMID: 31262025 PMCID: PMC6681006 DOI: 10.3390/brainsci9070155] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2019] [Revised: 06/20/2019] [Accepted: 06/26/2019] [Indexed: 01/08/2023] Open
Abstract
Transcriptome profiling can broadly characterize drug effects and risk for addiction in the absence of drug exposure. Modern large-scale molecular methods, including RNA-sequencing (RNA-Seq), have been extensively applied to alcohol-related disease traits, but rarely to risk for methamphetamine (MA) addiction. We used RNA-Seq data from selectively bred mice with high or low risk for voluntary MA intake to construct coexpression and cosplicing networks for differential risk. Three brain reward circuitry regions were explored, the nucleus accumbens (NAc), prefrontal cortex (PFC), and ventral midbrain (VMB). With respect to differential gene expression and wiring, the VMB was more strongly affected than either the PFC or NAc. Coexpression network connectivity was higher in the low MA drinking line than in the high MA drinking line in the VMB, oppositely affected in the NAc, and little impacted in the PFC. Gene modules protected from the effects of selection may help to eliminate certain mechanisms from significant involvement in risk for MA intake. One such module was enriched in genes with dopamine-associated annotations. Overall, the data suggest that mitochondrial function and glutamate-mediated synaptic plasticity have key roles in the outcomes of selective breeding for high versus low levels of MA intake.
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15
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Saul MC, Philip VM, Reinholdt LG, Chesler EJ. High-Diversity Mouse Populations for Complex Traits. Trends Genet 2019; 35:501-514. [PMID: 31133439 DOI: 10.1016/j.tig.2019.04.003] [Citation(s) in RCA: 102] [Impact Index Per Article: 20.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2019] [Revised: 04/19/2019] [Accepted: 04/22/2019] [Indexed: 12/21/2022]
Abstract
Contemporary mouse genetic reference populations are a powerful platform to discover complex disease mechanisms. Advanced high-diversity mouse populations include the Collaborative Cross (CC) strains, Diversity Outbred (DO) stock, and their isogenic founder strains. When used in systems genetics and integrative genomics analyses, these populations efficiently harnesses known genetic variation for precise and contextualized identification of complex disease mechanisms. Extensive genetic, genomic, and phenotypic data are already available for these high-diversity mouse populations and a growing suite of data analysis tools have been developed to support research on diverse mice. This integrated resource can be used to discover and evaluate disease mechanisms relevant across species.
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Affiliation(s)
- Michael C Saul
- The Jackson Laboratory for Mammalian Genetics, Bar Harbor, ME, USA
| | - Vivek M Philip
- The Jackson Laboratory for Mammalian Genetics, Bar Harbor, ME, USA
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- The Jackson Laboratory for Mammalian Genetics, Bar Harbor, ME, USA; UNC Chapel Hill, Chapel Hill, NC, USA; SUNY Binghamton, Binghamton, NY, USA; Pittsburgh University, Pittsburgh, PA, USA
| | - Elissa J Chesler
- The Jackson Laboratory for Mammalian Genetics, Bar Harbor, ME, USA.
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