1 4989 117 PCSK9 IS INCREASED IN CEREBROSPINAL FLUID OF INDIVIDUALS WITH ALCOHOL USE DISORDER. BACKGROUND: RECENT STUDIES HAVE SHOWN THAT ALCOHOL USE AFFECTS THE REGULATION AND EXPRESSION OF PROPROTEIN CONVERTASE SUBTILISIN/KEXIN 9 (PCSK9). WHILE A MAJOR ROLE OF PCSK9 IN HEPATIC FUNCTION AND LIPID REGULATION HAS BEEN CLEARLY ESTABLISHED, OTHER PLEIOTROPIC EFFECTS REMAIN POORLY UNDERSTOOD. EXISTING RESEARCH SUGGESTS A POSITIVE ASSOCIATION BETWEEN PCSK9 EXPRESSION IN THE BRAIN AND PSYCHOPATHOLOGY, WITH INCREASED LEVELS OF PCSK9 IN THE CEREBROSPINAL FLUID (CSF) OF INDIVIDUALS WITH DEMENTIA AND EPIGENETIC MODIFICATIONS OF PCSK9 ASSOCIATED WITH ALCOHOL USE DISORDER (AUD). IN THIS STUDY, WE HYPOTHESIZED THAT CHRONIC ALCOHOL USE WOULD INCREASE PCSK9 EXPRESSION IN CSF. METHODS: PCSK9 LEVELS IN CSF WERE MEASURED IN INDIVIDUALS WITH AUD (N = 42) ADMITTED TO AN INPATIENT REHABILITATION PROGRAM AND CONTROLS (N = 25). CSF SAMPLES IN AUD WERE ASSESSED AT 2 TIME POINTS, AT DAY 5 AND DAY 21 AFTER ADMISSION. FURTHERMORE, PLASMA SAMPLES WERE COLLECTED AND MEASURED FROM THE INDIVIDUALS WITH AUD. RESULTS: PCSK9 IN CSF WAS SIGNIFICANTLY INCREASED IN THE AUD GROUP AT DAY 5 AND DAY 21 COMPARED TO THE CONTROLS (P < 0.0001). PLASMA PCSK9 LEVELS WERE CORRELATED POSITIVELY WITH CSF PCSK9 LEVELS IN AUD (P = 0.0493). CONCLUSIONS: OUR DATA SUGGEST THAT PCSK9 IS ELEVATED IN THE CSF OF INDIVIDUALS WITH AUD, WHICH MAY INDICATE A POTENTIAL ROLE OF PCSK9 IN AUD. ADDITIONAL STUDIES ARE NECESSARY TO FURTHER ELUCIDATE THE FUNCTIONS OF PCSK9 IN THE BRAIN. 2019 2 4943 30 PATERNAL PRECONCEPTION ALCOHOL EXPOSURE IMPARTS INTERGENERATIONAL ALCOHOL-RELATED BEHAVIORS TO MALE OFFSPRING ON A PURE C57BL/6J BACKGROUND. 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-NAIVE 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-NAIVE 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. 2017 3 5498 32 REVIEW: DNA METHYLATION AND ALCOHOL USE DISORDERS: PROGRESS AND CHALLENGES. BACKGROUND AND OBJECTIVES: RISK FOR ALCOHOL USE DISORDERS (AUDS) IS INFLUENCED BY GENE-ENVIRONMENT INTERACTIONS. ENVIRONMENTAL FACTORS CAN AFFECT GENE EXPRESSION THROUGH EPIGENETIC MECHANISMS SUCH AS DNA METHYLATION. THIS REVIEW OUTLINES THE FINDINGS REGARDING THE ASSOCIATION OF DNA METHYLATION AND AUDS. METHODS: WE SEARCHED PUBMED (BY APRIL 2016) AND IDENTIFIED 29 STUDIES THAT EXAMINED THE ASSOCIATION OF DNA METHYLATION AND AUDS. WE ALSO EVALUATED THE METHODS USED IN THESE STUDIES. RESULTS: TWO STUDIES DEMONSTRATED ELEVATED GLOBAL (REPETITIVE ELEMENT) DNA METHYLATION LEVELS IN AUD SUBJECTS. FIFTEEN CANDIDATE GENE STUDIES SHOWED HYPERMETHYLATION OF PROMOTER REGIONS OF SIX GENES (AVP, DNMT3B, HERP, HTR3A, OPRM1, AND SNCA) OR HYPOMETHYLATION OF THE GDAP1 PROMOTER REGION IN AUD SUBJECTS. FIVE GENOME-WIDE DNA METHYLATION STUDIES DEMONSTRATED WIDESPREAD DNA METHYLATION CHANGES ACROSS THE GENOME IN AUD SUBJECTS. SIX STUDIES SHOWED SIGNIFICANT CORRELATIONS OF DNA METHYLATION WITH GENE EXPRESSION IN AUD SUBJECTS. THREE STUDIES REVEALED INTERACTIVE EFFECTS OF GENETIC VARIATION AND DNA METHYLATION ON SUSCEPTIBILITY TO AUDS. MOST STUDIES ANALYZED AUD-ASSOCIATED DNA METHYLATION CHANGES IN THE PERIPHERAL BLOOD; A FEW STUDIES EXAMINED DNA METHYLATION CHANGES IN POSTMORTEM BRAINS OF AUD SUBJECTS. DISCUSSION AND CONCLUSIONS: CHRONIC ALCOHOL CONSUMPTION MAY RESULT IN DNA METHYLATION CHANGES, LEADING TO NEUROADAPTATIONS THAT MAY UNDERLIE SOME OF THE MECHANISMS OF AUD RISK AND PERSISTENCE. FUTURE STUDIES ARE NEEDED TO CONFIRM THE FEW EXISTING RESULTS, AND THEN TO ELUCIDATE WHETHER DNA METHYLATION CHANGES ARE THE CAUSE OR CONSEQUENCE OF AUDS. SCIENTIFIC SIGNIFICANCE: DNA METHYLATION PROFILES MAY BE USED TO ASSESS AUD STATUS OR MONITOR AUD TREATMENT RESPONSE. (AM J ADDICT 2017;26:502-515). 2017 4 1875 41 EMERGING ROLE OF ONE-CARBON METABOLISM AND DNA METHYLATION ENRICHMENT ON DELTA-CONTAINING GABAA RECEPTOR EXPRESSION IN THE CEREBELLUM OF SUBJECTS WITH ALCOHOL USE DISORDERS (AUD). BACKGROUND: CEREBELLUM IS AN AREA OF THE BRAIN PARTICULARLY SENSITIVE TO THE EFFECTS OF ACUTE AND CHRONIC ALCOHOL CONSUMPTION. ALCOHOL EXPOSURE DECREASES CEREBELLAR PURKINJE CELL OUTPUT BY INCREASING GABA RELEASE FROM GOLGI CELLS ONTO EXTRASYNAPTIC ALPHA6/DELTA-CONTAINING GABAA RECEPTORS LOCATED ON GLUTAMATERGIC GRANULE CELLS. HERE, WE STUDIED WHETHER CHRONIC ALCOHOL CONSUMPTION INDUCES CHANGES IN GABAA RECEPTOR SUBUNIT EXPRESSION AND WHETHER THESE CHANGES ARE ASSOCIATED WITH ALTERATIONS IN EPIGENETIC MECHANISMS VIA DNA METHYLATION. METHODS: WE USED A COHORT OF POSTMORTEM CEREBELLUM FROM CONTROL AND CHRONIC ALCOHOLICS, HERE DEFINED AS ALCOHOL USE DISORDERS SUBJECTS (N=25/GROUP). S-ADENOSYL-METHIONINE/S-ADENOSYL-HOMOCYSTEINE WERE MEASURED BY HIGH-PERFORMANCE LIQUID CHROMATOGRAPHY. MRNA LEVELS OF VARIOUS GENES WERE ASSESSED BY REVERSE TRANSCRIPTASE-QUANTITATIVE POLYMERASE CHAIN REACTION. PROMOTER METHYLATION ENRICHMENT WAS ASSESSED USING METHYLATED DNA IMMUNOPRECIPITATION AND HYDROXY-METHYLATED DNA IMMUNOPRECIPITATION ASSAYS. RESULTS: MRNAS ENCODING KEY ENZYMES OF 1-CARBON METABOLISM THAT DETERMINE THE S-ADENOSYL-METHIONINE/S-ADENOSYL-HOMOCYSTEINE RATIO WERE INCREASED, INDICATING HIGHER "METHYLATION INDEX" IN ALCOHOL USE DISORDER SUBJECTS. WE FOUND THAT INCREASED METHYLATION OF THE PROMOTER OF THE DELTA SUBUNIT GABAA RECEPTOR WAS ASSOCIATED WITH REDUCED MRNA AND PROTEIN LEVELS IN THE CEREBELLUM OF ALCOHOL USE DISORDER SUBJECTS. NO CHANGES WERE OBSERVED IN ALPHA1- OR ALPHA6-CONTAINING GABAA RECEPTOR SUBUNITS. THE EXPRESSION OF DNA-METHYLTRANSFERASES (1, 3A, AND 3B) WAS UNALTERED, WHEREAS THE MRNA LEVEL OF TET1, WHICH PARTICIPATES IN THE DNA DEMETHYLATION PATHWAY, WAS DECREASED. HENCE, INCREASED METHYLATION OF THE DELTA SUBUNIT GABAA RECEPTOR PROMOTER MAY RESULT FROM ALCOHOL-INDUCED REDUCTION OF DNA DEMETHYLATION. CONCLUSION: TOGETHER, THESE RESULTS SUPPORT THE HYPOTHESIS THAT ABERRANT DNA METHYLATION PATHWAYS MAY BE INVOLVED IN CEREBELLAR PATHOPHYSIOLOGY OF ALCOHOLISM. FURTHERMORE, THIS WORK PROVIDES NOVEL EVIDENCE FOR A CENTRAL ROLE OF DNA METHYLATION MECHANISMS IN THE ALCOHOL-INDUCED NEUROADAPTIVE CHANGES OF HUMAN CEREBELLAR GABAA RECEPTOR FUNCTION. 2017 5 4257 41 METHYLOMIC PROFILING AND REPLICATION IMPLICATES DEREGULATION OF PCSK9 IN ALCOHOL USE DISORDER. ALCOHOL USE DISORDER (AUD) IS A COMMON AND CHRONIC DISORDER WITH SUBSTANTIAL EFFECTS ON PERSONAL AND PUBLIC HEALTH. THE UNDERLYING PATHOPHYSIOLOGY IS POORLY UNDERSTOOD BUT STRONG EVIDENCE SUGGESTS SIGNIFICANT ROLES OF BOTH GENETIC AND EPIGENETIC COMPONENTS. GIVEN THAT ALCOHOL AFFECTS MANY ORGAN SYSTEMS, WE PERFORMED A CROSS-TISSUE AND CROSS-PHENOTYPIC ANALYSIS OF GENOME-WIDE METHYLOMIC VARIATION IN AUD USING SAMPLES FROM 3 DISCOVERY, 4 REPLICATION, AND 2 TRANSLATIONAL COHORTS. WE IDENTIFIED A DIFFERENTIALLY METHYLATED REGION IN THE PROMOTER OF THE PROPROTEIN CONVERTASE SUBTILISIN/KEXIN 9 (PCSK9) GENE THAT WAS ASSOCIATED WITH DISEASE PHENOTYPES. BIOLOGICAL VALIDATION SHOWED THAT PCSK9 PROMOTER METHYLATION IS CONSERVED ACROSS TISSUES AND POSITIVELY CORRELATED WITH EXPRESSION. REPLICATION IN AUD DATASETS CONFIRMED PCSK9 HYPOMETHYLATION AND A TRANSLATIONAL MOUSE MODEL OF AUD SHOWED THAT ALCOHOL EXPOSURE LEADS TO PCSK9 DOWNREGULATION. PCSK9 IS PRIMARILY EXPRESSED IN THE LIVER AND REGULATES LOW-DENSITY LIPOPROTEIN CHOLESTEROL (LDL-C). OUR FINDING OF ALCOHOL-INDUCED EPIGENETIC REGULATION OF PCSK9 REPRESENTS ONE OF THE UNDERLYING MECHANISMS BETWEEN THE WELL-KNOWN EFFECTS OF ALCOHOL ON LIPID METABOLISM AND CARDIOVASCULAR RISK, WITH LIGHT ALCOHOL USE GENERALLY BEING PROTECTIVE WHILE CHRONIC HEAVY USE HAS DETRIMENTAL HEALTH OUTCOMES. 2018 6 6639 31 UNRAVELING THE EPIGENOMIC AND TRANSCRIPTOMIC INTERPLAY DURING ALCOHOL-INDUCED ANXIOLYSIS. POSITIVE EFFECTS OF ALCOHOL DRINKING SUCH AS ANXIOLYSIS AND EUPHORIA APPEAR TO BE A CRUCIAL FACTOR IN THE INITIATION AND MAINTENANCE OF ALCOHOL USE DISORDER (AUD). HOWEVER, THE MECHANISMS THAT LEAD FROM CHROMATIN REORGANIZATION TO TRANSCRIPTOMIC CHANGES AFTER ACUTE ETHANOL EXPOSURE REMAIN UNKNOWN. HERE, WE USED ASSAY FOR TRANSPOSASE-ACCESSIBLE CHROMATIN FOLLOWED BY HIGH THROUGHPUT SEQUENCING (ATAC-SEQ) AND RNA-SEQ TO INVESTIGATE EPIGENOMIC AND TRANSCRIPTOMIC CHANGES THAT UNDERLIE ANXIOLYTIC EFFECTS OF ACUTE ETHANOL USING AN ANIMAL MODEL. ANALYSIS OF ATAC-SEQ DATA REVEALED AN OVERALL OPEN OR PERMISSIVE CHROMATIN STATE THAT WAS ASSOCIATED WITH TRANSCRIPTOMIC CHANGES IN THE AMYGDALA AFTER ACUTE ETHANOL EXPOSURE. WE IDENTIFIED A CANDIDATE GENE, HIF3A (HYPOXIA-INDUCIBLE FACTOR 3, ALPHA SUBUNIT), THAT HAD 'OPEN' CHROMATIN REGIONS (ATAC-SEQ PEAKS), ASSOCIATED WITH SIGNIFICANTLY INCREASED ACTIVE EPIGENETIC HISTONE ACETYLATION MARKS AND DECREASED DNA METHYLATION AT THESE REGIONS. THE MRNA LEVELS OF HIF3A WERE INCREASED BY ACUTE ETHANOL EXPOSURE, BUT DECREASED IN THE AMYGDALA DURING WITHDRAWAL AFTER CHRONIC ETHANOL EXPOSURE. KNOCKDOWN OF HIF3A EXPRESSION IN THE CENTRAL NUCLEUS OF AMYGDALA ATTENUATED ACUTE ETHANOL-INDUCED INCREASES IN HIF3A MRNA LEVELS AND BLOCKED ANXIOLYSIS IN RATS. THESE DATA INDICATE THAT CHROMATIN ACCESSIBILITY AND TRANSCRIPTOMIC SIGNATURES IN THE AMYGDALA AFTER ACUTE ETHANOL EXPOSURE UNDERLIE ANXIOLYSIS AND POSSIBLY PRIME THE CHROMATIN FOR THE DEVELOPMENT OF AUD. 2022 7 3086 31 GENOME-WIDE TRANSCRIPTOMICS OF THE AMYGDALA REVEALS SIMILAR OLIGODENDROCYTE-RELATED RESPONSES TO ACUTE AND CHRONIC ALCOHOL DRINKING IN FEMALE MICE. REPEATED EXCESSIVE ALCOHOL CONSUMPTION IS A RISK FACTOR FOR ALCOHOL USE DISORDER (AUD). ALTHOUGH AUD HAS BEEN MORE COMMON IN MEN THAN WOMEN, WOMEN DEVELOP MORE SEVERE BEHAVIORAL AND PHYSICAL IMPAIRMENTS. HOWEVER, RELATIVELY FEW NEW THERAPEUTICS TARGETING DEVELOPMENT OF AUD, PARTICULARLY IN WOMEN, HAVE BEEN VALIDATED. TO GAIN A BETTER UNDERSTANDING OF MOLECULAR MECHANISMS UNDERLYING ALCOHOL INTAKE, WE CONDUCTED A GENOME-WIDE RNA-SEQUENCING ANALYSIS IN FEMALE MICE EXPOSED TO DIFFERENT MODES (ACUTE VS CHRONIC) OF ETHANOL DRINKING. WE FOCUSED ON TRANSCRIPTIONAL PROFILES IN THE AMYGDALA INCLUDING THE CENTRAL AND BASOLATERAL SUBNUCLEI, BRAIN AREAS PREVIOUSLY IMPLICATED IN ALCOHOL DRINKING AND SEEKING. SURPRISINGLY, WE FOUND THAT BOTH DRINKING MODES TRIGGERED SIMILAR CHANGES IN GENE EXPRESSION AND CANONICAL PATHWAYS, INCLUDING UPREGULATION OF RIBOSOME-RELATED/TRANSLATIONAL PATHWAYS AND MYELINATION PATHWAYS, AND DOWNREGULATION OF CHROMATIN BINDING AND HISTONE MODIFICATION. IN ADDITION, ANALYSES OF HUB GENES AND UPSTREAM REGULATORY PATHWAYS REVEALED THAT VOLUNTARY ETHANOL CONSUMPTION AFFECTS EPIGENETIC CHANGES VIA HISTONE DEACETYLATION PATHWAYS, OLIGODENDROCYTE AND MYELIN FUNCTION, AND THE OLIGODENDROCYTE-RELATED TRANSCRIPTION FACTOR, SOX17. FURTHERMORE, A VIRAL VECTOR-ASSISTED KNOCKDOWN OF SOX17 GENE EXPRESSION IN THE AMYGDALA PREVENTED A GRADUAL INCREASE IN ALCOHOL CONSUMPTION DURING REPEATED ACCESSES. OVERALL, THESE RESULTS SUGGEST THAT THE EXPRESSION OF OLIGODENDROCYTE-RELATED GENES IN THE AMYGDALA IS SENSITIVE TO VOLUNTARY ALCOHOL DRINKING IN FEMALE MICE. THESE FINDINGS SUGGEST POTENTIAL MOLECULAR TARGETS FOR FUTURE THERAPEUTIC APPROACHES TO PREVENT THE DEVELOPMENT OF AUD, DUE TO REPEATED EXCESSIVE ALCOHOL CONSUMPTION, PARTICULARLY IN WOMEN. 2022 8 4931 35 PATERNAL ALCOHOL EXPOSURE REDUCES ALCOHOL DRINKING AND INCREASES BEHAVIORAL SENSITIVITY TO ALCOHOL SELECTIVELY IN MALE OFFSPRING. ALCOHOL USE DISORDER (AUD) IS HERITABLE, BUT THE GENETIC BASIS FOR THIS DISEASE REMAINS POORLY UNDERSTOOD. ALTHOUGH NUMEROUS GENE VARIANTS HAVE BEEN ASSOCIATED WITH AUD, THESE VARIANTS ACCOUNT FOR ONLY A SMALL FRACTION OF THE TOTAL RISK. THE IDEA OF INHERITANCE OF ACQUIRED CHARACTERISTICS, I.E. "EPIGENETIC INHERITANCE," IS RE-EMERGING AS A PROVEN ADJUNCT TO TRADITIONAL MODES OF GENETIC INHERITANCE. WE HYPOTHESIZED THAT ALCOHOL DRINKING AND NEUROBIOLOGICAL SENSITIVITY TO ALCOHOL ARE INFLUENCED BY ANCESTRAL ALCOHOL EXPOSURE. TO TEST THIS HYPOTHESIS, WE EXPOSED MALE MICE TO CHRONIC VAPOR ETHANOL OR CONTROL CONDITIONS, MATED THEM TO ETHANOL-NAIVE FEMALES, AND TESTED ADULT OFFSPRING FOR ETHANOL DRINKING, ETHANOL-INDUCED BEHAVIORS, GENE EXPRESSION, AND DNA METHYLATION. WE FOUND THAT ETHANOL-SIRED MALE OFFSPRING HAD REDUCED ETHANOL PREFERENCE AND CONSUMPTION, ENHANCED SENSITIVITY TO THE ANXIOLYTIC AND MOTOR-ENHANCING EFFECTS OF ETHANOL, AND INCREASED BDNF EXPRESSION IN THE VENTRAL TEGMENTAL AREA (VTA) COMPARED TO CONTROL-SIRED MALE OFFSPRING. THERE WERE NO DIFFERENCES AMONG ETHANOL- AND CONTROL-SIRED FEMALE OFFSPRING ON THESE ASSAYS. ETHANOL EXPOSURE ALSO DECREASED DNA METHYLATION AT THE BDNFAEPROMOTER OF SIRE'S GERM CELLS AND HYPOMETHYLATION WAS MAINTAINED IN THE VTA OF BOTH MALE AND FEMALE ETHANOL-SIRED OFFSPRING. OUR FINDINGS SHOW THAT PATERNAL ALCOHOL EXPOSURE IS A PREVIOUSLY UNRECOGNIZED REGULATOR OF ALCOHOL DRINKING AND BEHAVIORAL SENSITIVITY TO ALCOHOL IN MALE, BUT NOT FEMALE, OFFSPRING. PATERNAL ALCOHOL EXPOSURE ALSO INDUCES EPIGENETIC ALTERATIONS (DNA HYPOMETHYLATION) AND GENE EXPRESSION CHANGES THAT PERSIST IN THE VTA OF OFFSPRING. THESE RESULTS PROVIDE NEW INSIGHT INTO THE INHERITANCE AND DEVELOPMENT OF ALCOHOL DRINKING BEHAVIORS. 2014 9 6177 31 THE HISTONE METHYLTRANSFERASE G9A MEDIATES STRESS-REGULATED ALCOHOL DRINKING. THE EPIGENETIC ENZYME G9A IS A HISTONE METHYLTRANSFERASE THAT DIMETHYLATES LYSINE 9 ON HISTONE H3 (H3K9ME2), AND IN THE ADULT NUCLEUS ACCUMBENS (NAC), G9A REGULATES MULTIPLE BEHAVIORS ASSOCIATED WITH SUBSTANCE USE DISORDER. WE SHOW HERE THAT CHRONIC INTERMITTENT ETHANOL (CIE) EXPOSURE IN MALE MICE REDUCED BOTH G9A AND H3K9ME2 LEVELS IN THE ADULT NAC, BUT NOT DORSAL STRIATUM. VIRAL-MEDIATED REDUCTION OF G9A IN THE NAC HAD NO EFFECTS ON BASELINE VOLITIONAL ETHANOL DRINKING OR ESCALATED ALCOHOL DRINKING PRODUCED BY CIE EXPOSURE; HOWEVER, NAC G9A WAS REQUIRED FOR STRESS-REGULATED CHANGES IN ETHANOL DRINKING, INCLUDING POTENTIATED ALCOHOL DRINKING PRODUCED BY ACTIVATION OF THE KAPPA-OPIOID RECEPTOR. IN ADDITION, WE OBSERVED THAT CHRONIC SYSTEMIC ADMINISTRATION OF A G9A INHIBITOR, UNC0642, ALSO BLOCKED STRESS-POTENTIATED ALCOHOL DRINKING. TOGETHER, OUR FINDINGS SUGGEST THAT CHRONIC ALCOHOL USE, SIMILAR TO OTHER ABUSED SUBSTANCES, PRODUCES A NAC-SELECTIVE REDUCTION IN G9A LEVELS THAT SERVES TO LIMIT STRESS-REGULATED ALCOHOL DRINKING. MOREOVER, OUR FINDINGS SUGGEST THAT PHARMACOLOGICAL INHIBITION OF G9A MIGHT PROVIDE A NOVEL THERAPEUTIC APPROACH TO TREAT STRESS-INDUCED ALCOHOL DRINKING, WHICH IS A MAJOR TRIGGER OF RELAPSE IN INDIVIDUALS SUFFERING FROM AUD. 2022 10 3321 26 HISTONE ACETYLATION OF THE HTR3A GENE IN THE PREFRONTAL CORTEX OF WISTAR RATS REGULATES ETHANOL-SEEKING BEHAVIOR. PREVIOUS REPORTS SHOWED THAT DECREASED HISTONE DEACETYLASE ACTIVITY SIGNIFICANTLY POTENTIATED THE REWARDING EFFECTS OF PSYCHOSTIMULANTS, AND THAT ENCODING OF THE 5-HT3 RECEPTOR BY THE HTR3A GENE WAS RELATED TO ETHANOL-SEEKING BEHAVIOR. HOWEVER, THE EFFECTS OF A HISTONE DEACETYLASE INHIBITOR ON ETHANOL-SEEKING BEHAVIOR AND EPIGENETIC REGULATION OF HTR3A MRNA EXPRESSION AFTER CHRONIC ETHANOL EXPOSURE ARE NOT FULLY UNDERSTOOD. USING QUANTITATIVE REVERSE TRANSCRIPTION-POLYMERASE CHAIN REACTION AND CHROMATIN IMMUNOPRECIPITATION ANALYSIS, WE INVESTIGATED THE EFFECTS OF CHRONIC ETHANOL EXPOSURE AND ITS INTERACTION WITH A HISTONE DEACETYLASE INHIBITOR ON HISTONE-ACETYLATION-MEDIATED CHANGES IN HTR3A MRNA EXPRESSION IN THE HTR3A PROMOTER REGION. THE CONDITIONED PLACE PREFERENCE PROCEDURE WAS USED TO EVALUATE ETHANOL-SEEKING BEHAVIOR. CHRONIC EXPOSURE TO ETHANOL EFFECTIVELY ELICITED PLACE CONDITIONING. IN THE PREFRONTAL CORTEX, THE ACETYLATION OF H3K9 AND HTR3A MRNA EXPRESSION IN THE HTR3A PROMOTER REGION WERE SIGNIFICANTLY HIGHER IN THE ETHANOL GROUP THAN IN THE SALINE GROUP. THE HISTONE DEACETYLASE INHIBITOR SODIUM BUTYRATE POTENTIATED THE EFFECTS OF ETHANOL ON HTR3A MRNA EXPRESSION AND ENHANCED ETHANOL-INDUCED CONDITIONED PLACE PREFERENCES. THESE RESULTS SUGGEST THAT ETHANOL UPREGULATES HTR3A LEVELS THROUGH MECHANISMS INVOLVING H3K9 ACETYLATION, AND THAT HISTONE ACETYLATION MAY BE A THERAPEUTIC TARGET FOR TREATING ETHANOL ABUSE. 2012 11 3331 30 HISTONE DEACETYLASE INHIBITOR SUBERANILOHYDROXAMIC ACID TREATMENT REVERSES HYPOSENSITIVITY TO GAMMA-AMINOBUTYRIC ACID IN THE VENTRAL TEGMENTAL AREA DURING ETHANOL WITHDRAWAL. BACKGROUND: THE VENTRAL TEGMENTAL AREA (VTA) IS IMPORTANT FOR ALCOHOL-RELATED REWARD AND REINFORCEMENT. MOUSE VTA NEURONS ARE HYPOSENSITIVE TO GAMMA-AMINOBUTYRIC ACID (GABA) DURING ETHANOL (ETOH) WITHDRAWAL, AND GABA RESPONSIVENESS IS NORMALIZED BY IN VITRO TREATMENT WITH HISTONE DEACETYLASE INHIBITORS (HDACI). THE PRESENT STUDY EXAMINED THE EFFECT OF A SYSTEMICALLY ADMINISTERED HDACI, SUBERANILOHYDROXAMIC ACID (SAHA) ON GABA SENSITIVITY, AND RELATED MOLECULAR CHANGES IN VTA NEURONS DURING WITHDRAWAL AFTER CHRONIC ETOH INTAKE IN RATS. METHODS: SPRAGUE DAWLEY MALE ADULT RATS WERE FED WITH LIEBER-DECARLI DIET (9% ETOH OR CONTROL DIET) FOR 16 DAYS. EXPERIMENTAL GROUPS INCLUDED CONTROL DIET-FED AND ETOH DIET-FED (0- OR 24-HOUR WITHDRAWAL) RATS TREATED WITH EITHER SAHA OR VEHICLE INJECTION. SINGLE-UNIT RECORDINGS WERE USED TO MEASURE THE RESPONSE OF VTA NEURONS TO GABA. IMMUNOHISTOCHEMISTRY WAS PERFORMED TO EXAMINE LEVELS OF HDAC2, ACETYLATED HISTONE H3 LYSINE 9 (ACH3K9), AND GABA(A) RECEPTOR ALPHA1 AND ALPHA5 SUBUNITS IN THE VTA; QUANTITATIVE POLYMERASE CHAIN REACTION WAS PERFORMED TO EXAMINE THE MRNA LEVELS OF HDAC2 AND GABA(A) RECEPTOR SUBUNITS. RESULTS: VTA NEURONS FROM THE WITHDRAWAL GROUP EXHIBITED GABA HYPOSENSITIVITY. IN VIVO SAHA TREATMENT 2 HOURS BEFORE SACRIFICE NORMALIZED THE SENSITIVITY OF VTA NEURONS TO GABA. ETOH WITHDRAWAL WAS ASSOCIATED WITH INCREASED HDAC2 AND DECREASED ACH3K9 PROTEIN LEVELS; SAHA TREATMENT NORMALIZED ACH3K9 LEVELS. INTERESTINGLY, NO SIGNIFICANT CHANGE WAS OBSERVED IN THE MRNA LEVELS OF HDAC2. THE MRNA LEVELS, BUT NOT PROTEIN LEVELS, OF GABA(A) RECEPTOR ALPHA1 AND ALPHA5 SUBUNITS WERE INCREASED DURING WITHDRAWAL. CONCLUSIONS: WITHDRAWAL FROM CHRONIC ETOH EXPOSURE RESULTS IN A DECREASE IN GABA-MEDIATED INHIBITION, AND THIS GABA HYPOSENSITIVITY IS NORMALIZED BY IN VIVO SAHA TREATMENT. DISRUPTION OF SIGNALING IN THE VTA PRODUCED BY ALTERATION OF GABA NEUROTRANSMISSION COULD BE 1 NEUROADAPTIVE PHYSIOLOGICAL PROCESS LEADING TO CRAVING AND RELAPSE. THESE RESULTS SUGGEST THAT HDACI PHARMACOTHERAPY WITH AGENTS LIKE SAHA MIGHT BE AN EFFECTIVE TREATMENT FOR ALCOHOLISM. 2018 12 6019 36 THE ASSOCIATION OF HTR3A MRNA EXPRESSION AND CRAVING IN HAN CHINESE ALCOHOL-DEPENDENT PATIENTS: A PRELIMINARY STUDY. BACKGROUND: 5-HYDROXYTRYPTAMINE (5-HT) 3 RECEPTOR PLAYS A CRUCIAL ROLE IN CRAVING OF ALCOHOL DEPENDENCE. RECENT EVIDENCE SHOWS THAT CHRONIC ALCOHOL EXPOSURE CAUSES CHANGES IN GENE EXPRESSION AND INDUCES BEHAVIORAL CHANGES. HOWEVER, THE RELATIONSHIP BETWEEN GENE EXPRESSION OF 5-HT3 RECEPTOR AND CRAVING IN ALCOHOL-DEPENDENT PATIENTS IS NOT FULLY UNDERSTOOD. OBJECTIVES: THE AIM OF THIS PRELIMINARY STUDY WAS TO INVESTIGATE THE RELATIONSHIP BETWEEN GENE EXPRESSION OF THE 5-HT3 RECEPTOR AND CRAVING IN ALCOHOL-DEPENDENT PATIENTS AND THE EPIGENETIC MECHANISM. METHODS: WE RECRUITED 50 MALE HAN CHINESE ALCOHOL-DEPENDENT PATIENTS AND 46 MALE HAN CHINESE HEALTHY CONTROLS. WE INVESTIGATED THE CHANGES OF HTR3A MRNA, WHICH ENCODES THE 5-HT3 RECEPTOR A SUBUNIT, AND H3K9 ACETYLATION IN HTR3A PROMOTER REGION. OBSESSIVE COMPULSIVE DRINKING SCALE (OCDS) WAS USED TO ASSESS THE CRAVING OF ALCOHOL-DEPENDENT PATIENTS RELATIVE TO CONTROLS. RESULTS: HTR3A MRNA EXPRESSION LEVELS AND ACETYLATION LEVELS OF H3K9 IN THE HTR3A PROMOTER REGION WERE SIGNIFICANTLY HIGHER IN THE ALCOHOL-DEPENDENT PATIENTS. HTR3A MRNA EXPRESSION LEVELS WERE POSITIVELY CORRELATED WITH OCDS SCORES. MOREOVER, HTR3A MRNA EXPRESSION LEVELS WERE POSITIVELY CORRELATED WITH ACETYLATION LEVELS OF H3K9 IN HTR3A PROMOTER REGION. CONCLUSION: THE CURRENT FINDINGS SUGGEST THAT HTR3A MRNA EXPRESSION LEVELS WERE POSITIVELY CORRELATED WITH CRAVING IN HAN CHINESE ALCOHOL-DEPENDENT PATIENTS. THE REGULATION OF H3K9 HISTONE ACETYLATION IN HTR3A PROMOTER REGION MAY OFFER A TARGET FOR THE TREATMENT OF ALCOHOL DEPENDENCE. 2016 13 3080 36 GENOME-WIDE METHYLATION IN ALCOHOL USE DISORDER SUBJECTS: IMPLICATIONS FOR AN EPIGENETIC REGULATION OF THE CORTICO-LIMBIC GLUCOCORTICOID RECEPTORS (NR3C1). ENVIRONMENTAL FACTORS, INCLUDING SUBSTANCE ABUSE AND STRESS, CAUSE LONG-LASTING CHANGES IN THE REGULATION OF GENE EXPRESSION IN THE BRAIN VIA EPIGENETIC MECHANISMS, SUCH AS DNA METHYLATION. WE EXAMINED GENOME-WIDE DNA METHYLATION PATTERNS IN THE PREFRONTAL CORTEX (PFC, BA10) OF 25 PAIRS OF CONTROL AND INDIVIDUALS WITH ALCOHOL USE DISORDER (AUD), USING THE INFINIUM((R)) METHYLATIONEPIC BEADCHIP. WE IDENTIFIED 5254 DIFFERENTIALLY METHYLATED CPGS (P(NOMINAL) < 0.005). BIOINFORMATIC ANALYSES HIGHLIGHTED BIOLOGICAL PROCESSES CONTAINING GENES RELATED TO STRESS ADAPTATION, INCLUDING THE GLUCOCORTICOID RECEPTOR (ENCODED BY NR3C1). CONSIDERING THAT ALCOHOL IS A STRESSOR, WE FOCUSED OUR ATTENTION ON DIFFERENTIALLY METHYLATED REGIONS OF THE NR3C1 GENE AND VALIDATED THE DIFFERENTIAL METHYLATION OF SEVERAL GENES IN THE NR3C1 NETWORK. CHRONIC ALCOHOL DRINKING RESULTS IN A SIGNIFICANT INCREASED METHYLATION OF THE NR3C1 EXON VARIANT 1(H), WITH A PARTICULAR INCREASE IN THE LEVELS OF 5-HYDROXYMETHYLCYTOSINE OVER 5-METHYLCYTOSINE. THESE CHANGES IN DNA METHYLATION WERE ASSOCIATED WITH REDUCED NR3C1 MRNA AND PROTEIN EXPRESSION LEVELS IN PFC, AS WELL AS OTHER CORTICO-LIMBIC REGIONS OF AUD SUBJECTS WHEN COMPARED WITH CONTROLS. FURTHERMORE, WE SHOW THAT THE EXPRESSION OF SEVERAL STRESS-RESPONSIVE GENES (E.G., CRF, POMC, AND FKBP5) IS ALTERED IN THE PFC OF AUD SUBJECTS. THESE STRESS-RESPONSE GENES WERE ALSO CHANGED IN THE HIPPOCAMPUS, A REGION THAT IS HIGHLY SUSCEPTIBLE TO STRESS. THESE DATA SUGGEST THAT ALCOHOL-DEPENDENT ABERRANT DNA METHYLATION OF NR3C1 AND CONSEQUENT CHANGES IN OTHER STRESS-RELATED GENES MIGHT BE FUNDAMENTAL IN THE PATHOPHYSIOLOGY OF AUD AND LAY THE GROUNDWORK FOR TREATMENTS TARGETING THE EPIGENETIC MECHANISMS REGULATING NR3C1 IN AUD. 2021 14 6175 35 THE HISTONE DEACETYLASE INHIBITOR SUBEROYLANILIDE HYDROXAMIC ACID (SAHA) ALLEVIATES DEPRESSION-LIKE BEHAVIOR AND NORMALIZES EPIGENETIC CHANGES IN THE HIPPOCAMPUS DURING ETHANOL WITHDRAWAL. WITHDRAWAL FROM CHRONIC ALCOHOL DRINKING CAN CAUSE DEPRESSION, LEADING TO AN INABILITY TO FUNCTION IN DAILY LIFE AND AN INCREASED RISK FOR RELAPSE TO HARMFUL DRINKING. UNDERSTANDING THE CAUSES OF ALCOHOL WITHDRAWAL-RELATED DEPRESSION MAY LEAD TO NEW THERAPEUTIC TARGETS FOR TREATMENT. EPIGENETIC FACTORS HAVE RECENTLY EMERGED AS IMPORTANT CONTRIBUTORS TO BOTH DEPRESSION AND ALCOHOL USE DISORDER (AUD). SPECIFICALLY, ACETYLATION OF THE N-TERMINAL TAILS OF HISTONE PROTEINS THAT PACKAGE DNA INTO NUCLEOSOMES IS ALTERED IN STRESS-INDUCED MODELS OF DEPRESSION AND DURING ALCOHOL WITHDRAWAL. THE GOAL OF THIS STUDY WAS TO EXAMINE DEPRESSION-LIKE BEHAVIOR DURING ALCOHOL WITHDRAWAL AND ASSOCIATED CHANGES IN HISTONE ACETYLATION AND EXPRESSION OF HISTONE DEACETYLASE 2 (HDAC2) IN THE HIPPOCAMPUS, A BRAIN REGION CRITICAL FOR MOOD REGULATION AND DEPRESSION. MALE SPRAGUE-DAWLEY RATS WERE TREATED WITH THE LIEBER-DECARLI ETHANOL LIQUID DIET FOR 15 DAYS AND THEN UNDERWENT WITHDRAWAL. RATS WERE TREATED WITH THE HDAC INHIBITOR, SUBEROYLANILIDE HYDROXAMIC ACID (SAHA), DURING WITHDRAWAL AND WERE TESTED FOR DEPRESSION-LIKE BEHAVIOR. IN A SEPARATE GROUP OF RATS, THE HIPPOCAMPUS WAS ANALYZED FOR MRNA AND PROTEIN EXPRESSION OF HDAC2 AND LEVELS OF HISTONE H3 LYSINE 9 ACETYLATION (H3K9AC) DURING CHRONIC ETHANOL EXPOSURE AND WITHDRAWAL. RATS UNDERGOING ETHANOL WITHDRAWAL EXHIBITED DEPRESSION-LIKE BEHAVIOR AND HAD INCREASED HDAC2 AND DECREASED H3K9AC LEVELS IN SPECIFIC STRUCTURES OF THE HIPPOCAMPUS. TREATMENT WITH SAHA DURING WITHDRAWAL AMELIORATED DEPRESSION-LIKE BEHAVIOR AND NORMALIZED CHANGES IN HIPPOCAMPAL HDAC2 AND H3K9AC LEVELS. THESE RESULTS DEMONSTRATE THAT ETHANOL WITHDRAWAL CAUSES AN ALTERED EPIGENETIC STATE IN THE HIPPOCAMPUS. TREATMENT WITH AN HDAC INHIBITOR CAN CORRECT THIS STATE AND ALLEVIATE DEPRESSION-LIKE SYMPTOMS DEVELOPED DURING WITHDRAWAL. TARGETING HISTONE ACETYLATION MAY BE A NOVEL STRATEGY TO REDUCE ETHANOL WITHDRAWAL-INDUCED DEPRESSION. 2019 15 2319 42 EPIGENETIC REGULATION OF GABAERGIC NEUROTRANSMISSION AND NEUROSTEROID BIOSYNTHESIS IN ALCOHOL USE DISORDER. BACKGROUND: ALCOHOL USE DISORDER (AUD) IS A CHRONIC RELAPSING BRAIN DISORDER. GABAA RECEPTOR (GABAAR) SUBUNITS ARE A TARGET FOR THE PHARMACOLOGICAL EFFECTS OF ALCOHOL. NEUROSTEROIDS PLAY AN IMPORTANT ROLE IN THE FINE-TUNING OF GABAAR FUNCTION IN THE BRAIN. RECENTLY, WE HAVE SHOWN THAT AUD IS ASSOCIATED WITH CHANGES IN DNA METHYLATION MECHANISMS. HOWEVER, THE ROLE OF DNA METHYLATION IN THE REGULATION OF NEUROSTEROID BIOSYNTHESIS AND GABAERGIC NEUROTRANSMISSION IN AUD PATIENTS REMAINS UNDER-INVESTIGATED. METHODS: IN A COHORT OF POSTMORTEM BRAINS FROM 20 MALE CONTROLS AND AUD PATIENTS, WE INVESTIGATED THE EXPRESSION OF GABAAR SUBUNITS AND NEUROSTEROID BIOSYNTHETIC ENZYMES AND THEIR REGULATION BY DNA METHYLATION MECHANISMS. NEUROSTEROID LEVELS WERE QUANTIFIED BY GAS CHROMATOGRAPHY-MASS SPECTROMETRY. RESULTS: THE ALPHA 2 SUBUNIT EXPRESSION WAS REDUCED DUE TO INCREASED DNA METHYLATION AT THE GENE PROMOTER REGION IN THE CEREBELLUM OF AUD PATIENTS, A BRAIN AREA PARTICULARLY SENSITIVE TO THE EFFECTS OF ALCOHOL. ALCOHOL-INDUCED ALTERATION IN GABAAR SUBUNITS WAS ALSO OBSERVED IN THE PREFRONTAL CORTEX. NEUROSTEROID BIOSYNTHESIS WAS ALSO AFFECTED WITH REDUCED CEREBELLAR EXPRESSION OF THE 18KDA TRANSLOCATOR PROTEIN AND 3ALPHA-HYDROXYSTEROID DEHYDROGENASE MRNAS. NOTABLY, INCREASED DNA METHYLATION LEVELS WERE OBSERVED AT THE PROMOTER REGION OF 3ALPHA-HYDROXYSTEROID DEHYDROGENASE. THESE CHANGES WERE ASSOCIATED WITH MARKEDLY REDUCED LEVELS OF ALLOPREGNANOLONE AND PREGNANOLONE IN THE CEREBELLUM. CONCLUSION: GIVEN THE KEY ROLE OF NEUROSTEROIDS IN MODULATING THE STRENGTH OF GABAAR-MEDIATED INHIBITION, OUR DATA SUGGEST THAT ALCOHOL-INDUCED IMPAIRMENTS IN GABAERGIC NEUROTRANSMISSION MIGHT BE PROFOUNDLY IMPACTED BY REDUCED NEUROSTEROID BIOSYNTHESIS MOST LIKELY VIA DNA HYPERMETHYLATION. 2021 16 5177 39 PREFRONTAL CORTEX EXPRESSION OF CHROMATIN MODIFIER GENES IN MALE WSP AND WSR MICE CHANGES ACROSS ETHANOL DEPENDENCE, WITHDRAWAL, AND ABSTINENCE. ALCOHOL-USE DISORDER (AUD) IS A RELAPSING DISORDER ASSOCIATED WITH EXCESSIVE ETHANOL CONSUMPTION. RECENT STUDIES SUPPORT THE INVOLVEMENT OF EPIGENETIC MECHANISMS IN THE DEVELOPMENT OF AUD. STUDIES CARRIED OUT SO FAR HAVE FOCUSED ON A FEW SPECIFIC EPIGENETIC MODIFICATIONS. THE GOAL OF THIS PROJECT WAS TO INVESTIGATE GENE EXPRESSION CHANGES OF EPIGENETIC REGULATORS THAT MEDIATE A BROAD ARRAY OF CHROMATIN MODIFICATIONS AFTER CHRONIC ALCOHOL EXPOSURE, CHRONIC ALCOHOL EXPOSURE FOLLOWED BY 8 H WITHDRAWAL, AND CHRONIC ALCOHOL EXPOSURE FOLLOWED BY 21 DAYS OF ABSTINENCE IN WITHDRAWAL-RESISTANT (WSR) AND WITHDRAWAL SEIZURE-PRONE (WSP) SELECTED MOUSE LINES. WE FOUND THAT CHRONIC VAPOR EXPOSURE TO HIGHLY INTOXICATING LEVELS OF ETHANOL ALTERS THE EXPRESSION OF SEVERAL CHROMATIN REMODELING GENES MEASURED BY QUANTITATIVE PCR ARRAY ANALYSES. THE IDENTIFIED EFFECTS WERE INDEPENDENT OF SELECTED LINES, WHICH, HOWEVER, DISPLAYED BASELINE DIFFERENCES IN EPIGENETIC GENE EXPRESSION. WE REPORTED DYSREGULATION IN THE EXPRESSION OF GENES INVOLVED IN HISTONE ACETYLATION, DEACETYLATION, LYSINE AND ARGININE METHYLATION AND UBIQUITINATIONHYLATION DURING CHRONIC ETHANOL EXPOSURE AND WITHDRAWAL, BUT NOT AFTER 21 DAYS OF ABSTINENCE. ETHANOL-INDUCED CHANGES ARE CONSISTENT WITH DECREASED HISTONE ACETYLATION AND WITH DECREASED DEPOSITION OF THE PERMISSIVE UBIQUITINATION MARK H2BK120UB, ASSOCIATED WITH REDUCED TRANSCRIPTION. ON THE OTHER HAND, ETHANOL-INDUCED CHANGES IN THE EXPRESSION OF GENES INVOLVED IN HISTONE LYSINE METHYLATION ARE CONSISTENT WITH INCREASED TRANSCRIPTION. THE NET RESULT OF THESE MODIFICATIONS ON GENE EXPRESSION IS LIKELY TO DEPEND ON THE COMBINATION OF THE SPECIFIC HISTONE TAIL MODIFICATIONS PRESENT AT A GIVEN TIME ON A GIVEN PROMOTER. SINCE ALCOHOL DOES NOT MODULATE GENE EXPRESSION UNIDIRECTIONALLY, IT IS NOT SURPRISING THAT ALCOHOL DOES NOT UNIDIRECTIONALLY ALTER CHROMATIN STRUCTURE TOWARD A CLOSED OR OPEN STATE, AS SUGGESTED BY THE RESULTS OF THIS STUDY. 2017 17 6352 27 THE ROLE OF GABA(A) RECEPTORS IN THE DEVELOPMENT OF ALCOHOLISM. ALCOHOLISM IS A COMMON, HERITABLE, CHRONIC RELAPSING DISORDER. GABA(A) RECEPTORS UNDERGO ALLOSTERIC MODULATION BY ETHANOL, ANESTHETICS, BENZODIAZEPINES AND NEUROSTEROIDS AND HAVE BEEN IMPLICATED IN THE ACUTE AS WELL AS THE CHRONIC EFFECTS OF ETHANOL INCLUDING TOLERANCE, DEPENDENCE AND WITHDRAWAL. MEDICATIONS TARGETING GABA(A) RECEPTORS AMELIORATE THE SYMPTOMS OF ACUTE WITHDRAWAL. ETHANOL INDUCES PLASTICITY IN GABA(A) RECEPTORS: TOLERANCE IS ASSOCIATED WITH GENERALLY DECREASED GABA(A) RECEPTOR ACTIVATION AND DIFFERENTIALLY ALTERED SUBUNIT EXPRESSION. THE DOPAMINE (DA) MESOLIMBIC REWARD PATHWAY ORIGINATING IN THE VENTRAL TEGMENTAL AREA (VTA), AND INTERACTING STRESS CIRCUITRY PLAY AN IMPORTANT ROLE IN THE DEVELOPMENT OF ADDICTION. VTA GABAERGIC INTERNEURONS ARE THE PRIMARY INHIBITORY REGULATORS OF DA NEURONS AND A SUBSET OF VTA GABA(A) RECEPTORS MAY BE IMPLICATED IN THE SWITCH FROM HEAVY DRINKING TO DEPENDENCE. GABA(A) RECEPTORS MODULATE ANXIETY AND RESPONSE TO STRESS; IMPORTANT ELEMENTS OF SUSTAINED DRINKING AND RELAPSE. THE GABA(A) RECEPTOR SUBUNIT GENES CLUSTERED ON CHROMOSOME 4 ARE HIGHLY EXPRESSED IN THE REWARD PATHWAY. SEVERAL RECENT STUDIES HAVE PROVIDED STRONG EVIDENCE THAT ONE OF THESE GENES, GABRA2, IS IMPLICATED IN ALCOHOLISM IN HUMANS. THE INFLUENCE OF THE INTERACTION BETWEEN ETHANOL AND GABA(A) RECEPTORS IN THE REWARD PATHWAY ON THE DEVELOPMENT OF ALCOHOLISM TOGETHER WITH GENETIC AND EPIGENETIC VULNERABILITIES WILL BE EXPLORED IN THIS REVIEW. 2008 18 4944 30 PATERNAL PRECONCEPTION ETHANOL EXPOSURE BLUNTS HYPOTHALAMIC-PITUITARY-ADRENAL AXIS RESPONSIVITY AND STRESS-INDUCED EXCESSIVE FLUID INTAKE IN MALE MICE. 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-NAIVE 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. 2016 19 4930 36 PATERNAL ALCOHOL EXPOSURE REDUCES ACQUISITION OF OPERANT ALCOHOL SELF-ADMINISTRATION AND AFFECTS BDNF DNA METHYLATION IN MALE AND FEMALE OFFSPRING. FAMILIAL TRANSMISSION OF ALCOHOL USE DISORDER REFLECTS GENETIC AND ENVIRONMENTAL FACTORS. PATERNAL ALCOHOL EXPOSURE MAY AFFECT RODENT OFFSPRING VIA EPIGENETIC MODIFICATIONS TRANSMITTED THROUGH THE MALE GERM LINE. WHILE SUCH EXPOSURE ALTERS ALCOHOL SENSITIVITY IN MOUSE OFFSPRING, NO STUDIES EXAMINED IF IT IMPACTS THE DEVELOPMENT OF OPERANT ALCOHOL SELF-ADMINISTRATION IN RATS. WE EXPOSED MALE (SIRES) WISTAR RATS TO CHRONIC INTERMITTENT ETHANOL IN VAPOUR CHAMBERS (16 H/DAY; 5 DAYS/WEEK) OR TO AIR FOR 6 WEEKS. EIGHT WEEKS LATER, RATS WERE MATED WITH ALCOHOL-NAIVE FEMALES. ADULT ALCOHOL- AND CONTROL-SIRED F1 OFFSPRING WERE ASSESSED IN ACQUISITION OF ALCOHOL SELF-ADMINISTRATION IN WHICH INCREASING ALCOHOL CONCENTRATIONS (2.5%, 5% AND 10%, V/V) WERE DELIVERED AFTER ONE LEVER PRESS (FIXED RATIO 1 OR FR1). PRIOR TO ALCOHOL SESSIONS, RATS WERE TRAINED TO LEVER PRESS FOR FOOD DELIVERY UNDER AN FR1 SCHEDULE OF REINFORCEMENT. DNA METHYLATION LEVELS OF THE BRAIN DERIVED NEUROTROPHIC FACTOR (BDNF) GENE WERE MEASURED IN SPERM, NUCLEUS ACCUMBENS (NAC) AND MEDIAL PREFRONTAL CORTEX (MPFC) IN SIRES AND IN OFFSPRING. ALCOHOL-EXPOSED SIRES HAD LOWER BDNF DNA METHYLATION LEVELS IN NAC AND GREATER METHYLATION LEVELS IN MPFC. ALTHOUGH THIS PATTERN WAS NOT RECAPITULATED IN OFFSPRING, ALCOHOL-SIRED OFFSPRING OF BOTH SEXES DID SHOW ABERRANT BDNF DNA METHYLATION PATTERNS COMPARED TO CONTROL-SIRED OFFSPRING. ALCOHOL-SIRED OFFSPRING SELF-ADMINISTERED LESS ALCOHOL (5% AND 10%) WITH NO GROUP DIFFERENCES IN FOOD RESPONDING. RESULTS INDICATE THAT PATERNAL ALCOHOL EXPOSURE PRIOR TO CONCEPTION PROTECTS AGAINST ALCOHOL'S INITIAL REINFORCING EFFECTS BUT THE PATTERN OF DYSREGULATED BDNF METHYLATION IN REWARD-RELATED CIRCUITRY DID NOT MIMIC CHANGES SEEN IN SIRES. 2022 20 5445 38 REPEATED VAPOR ETHANOL EXPOSURE INDUCES TRANSIENT HISTONE MODIFICATIONS IN THE BRAIN THAT ARE MODIFIED BY GENOTYPE AND BRAIN REGION. 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 ALPHA1SHLA 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 ALPHA1SHLA 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. 2015