1 2319 123 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	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               
2 3093  35 GENOMIC AND EPIGENOMIC RESPONSES TO CHRONIC STRESS INVOLVE MIRNA-MEDIATED PROGRAMMING. STRESS REPRESENTS A CRITICAL INFLUENCE ON MOTOR SYSTEM FUNCTION AND HAS BEEN SHOWN TO IMPAIR MOVEMENT PERFORMANCE. WE HYPOTHESIZED THAT STRESS-INDUCED MOTOR IMPAIRMENTS ARE DUE TO BRAIN-SPECIFIC CHANGES IN MIRNA AND PROTEIN-ENCODING GENE EXPRESSION. HERE WE SHOW A CAUSAL LINK BETWEEN STRESS-INDUCED MOTOR IMPAIRMENT AND ASSOCIATED GENETIC AND EPIGENETIC RESPONSES IN RELEVANT CENTRAL MOTOR AREAS IN A RAT MODEL. EXPOSURE TO TWO WEEKS OF MILD RESTRAINT STRESS ALTERED THE EXPRESSION OF 39 GENES AND NINE MIRNAS IN THE CEREBELLUM. IN LINE WITH PERSISTENT BEHAVIOURAL IMPAIRMENTS, SOME CHANGES IN GENE AND MIRNA EXPRESSION WERE RESISTANT TO RECOVERY FROM STRESS. INTERESTINGLY, STRESS UP-REGULATED THE EXPRESSION OF ADIPOQ AND PROLACTIN RECEPTOR MRNAS IN THE CEREBELLUM. STRESS ALSO ALTERED THE EXPRESSION OF PRLR, MIR-186, AND MIR-709 IN HIPPOCAMPUS AND PREFRONTAL CORTEX. IN ADDITION, OUR FINDINGS DEMONSTRATE THAT MIR-186 TARGETS THE GENE EPS15. FURTHERMORE, WE FOUND AN AGE-DEPENDENT INCREASE IN EPHRINB3 AND GABAA4 RECEPTORS. THESE DATA SHOW THAT EVEN MILD STRESS RESULTS IN SUBSTANTIAL GENOMIC AND EPIGENOMIC CHANGES INVOLVING MIRNA EXPRESSION AND ASSOCIATED GENE TARGETS IN THE MOTOR SYSTEM. THESE FINDINGS SUGGEST A CENTRAL ROLE OF MIRNA-REGULATED GENE EXPRESSION IN THE STRESS RESPONSE AND IN ASSOCIATED NEUROLOGICAL FUNCTION.	2012	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               
3  989  35 CHRONIC SOCIAL DEFEAT STRESS DIFFERENTIALLY REGULATES THE EXPRESSION OF BDNF TRANSCRIPTS AND EPIGENETIC MODIFYING ENZYMES IN SUSCEPTIBLE AND RESILIENT MICE. OBJECTIVES: ALTHOUGH STRESS IS CONSIDERED A PRIMARY RISK FACTOR FOR NEUROPSYCHIATRIC DISORDERS, A MAJORITY OF INDIVIDUALS ARE RESILIENT TO THE EFFECTS OF STRESS EXPOSURE AND SUCCESSFULLY ADAPT TO ADVERSE LIFE EVENTS, WHILE OTHERS, THE SO-CALLED SUSCEPTIBLE INDIVIDUALS, MAY HAVE PROBLEMS TO PROPERLY ADAPT TO ENVIRONMENTAL CHANGES. HOWEVER, THE MECHANISMS UNDERLYING THESE DIFFERENT RESPONSES TO STRESS EXPOSURE ARE POORLY UNDERSTOOD.METHODS: ADULT MALE C57BL/6J MICE WERE EXPOSED TO CHRONIC SOCIAL DEFEAT STRESS PROTOCOL AND LEVELS OF BRAIN DERIVED NEUROTROPHIC FACTOR (BDNF) TRANSCRIPTS AND EPIGENETIC MODIFYING ENZYMES WERE ANALYSED BY REAL-TIME PCR IN THE HIPPOCAMPUS (HPC) AND PREFRONTAL CORTEX (PFC) OF SUSCEPTIBLE AND RESILIENT MICE.RESULTS: WE FOUND A SELECTIVE REDUCTION OF BDNF-6 TRANSCRIPT IN THE HPC AND AN INCREASE OF BDNF-4 TRANSCRIPT IN THE PFC OF SUSCEPTIBLE MICE. MOREOVER, SUSCEPTIBLE MICE SHOWED A SELECTIVE REDUCTION OF THE G9A MRNA LEVELS IN THE HPC, WHILE HDAC-5 AND DNMT3A MRNA LEVELS WERE SPECIFICALLY REDUCED IN THE PFC.CONCLUSIONS: OVERALL, OUR RESULTS, SHOWING A DIFFERENT EXPRESSION OF BDNF TRANSCRIPTS AND EPIGENETIC MODIFYING ENZYMES IN SUSCEPTIBLE AND RESILIENT MICE, SUGGEST THAT STRESS RESILIENCE IS NOT SIMPLY A LACK OF ACTIVATION OF STRESS-RELATED PATHWAYS, BUT IS RELATED TO THE ACTIVATION OF ADDITIONAL DIFFERENT SPECIFIC MECHANISMS.	2019	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    
4 6804  45 [EPIGENETIC REGULATION IN DEPRESSION]. RECENT RESEARCH HAS RAISED THE NOTION THAT EPIGENETIC MECHANISMS (E.G., DNA METHYLATION AND HISTONE MODIFICATIONS), WHICH EXERT LASTING CONTROL OVER GENE EXPRESSION WITHOUT ALTERING THE GENETIC CODE, COULD MEDIATE STABLE CHANGES IN BRAIN FUNCTION. HOWEVER, THE ROLE OF ENVIRONMENTAL FACTORS ALONG WITH GENETIC FACTORS IN THE EPIGENETIC REGULATION OF THE PATHOGENESIS OF DEPRESSION IS LARGELY UNKNOWN. TWO GENETICALLY DISTINCT MICE STRAINS, BALB/C (BALB) AND C57BL/6 (B6), EXHIBIT DIFFERENT BEHAVIORAL RESPONSES TO CHRONIC STRESS. WITH CHRONIC STRESS, BALB MICE SHOWED DEPRESSIVE-LIKE BEHAVIORS, BUT NOT B6 MICE, AND GLIAL CELL-DERIVED NEUROTROPHIC FACTOR (GDNF) EXPRESSION LEVEL WAS DECREASED IN THE VENTRAL STRIATUM OF BALB MICE BUT INCREASED IN B6 MICE. IN BALB MICE, DEPRESSIVE-LIKE BEHAVIORS AND DECREASED GDNF EXPRESSION WERE RECOVERED BY CHRONIC ANTIDEPRESSANT TREATMENT. THEREFORE, WE USED THESE TWO MICE STRAINS TO INVESTIGATE HOW THE EPIGENETIC STATUS OF THE GDNF GENE IN THE VENTRAL STRIATUM MODULATES STRESS VULNERABILITY. BOTH MICE STRAINS SHOWED INCREASED DNA METHYLATION LEVELS AND MECP2 RECRUITMENT IN THE GDNF PROMOTER REGION. HOWEVER, HISTONE H3 ACETYLATION LEVEL WAS DECREASED IN BALB MICE, BUT INCREASED IN B6 MICE. FURTHERMORE, BALB MICE SHOWED INCREASED HISTONE DEACETYLASE2 (HDAC2) EXPRESSION LEVEL AND RE-CHIP ASSAY REVEALED HDAC2-MECP2 COMPLEX IN BALB MICE. OUR RESULTS INDICATE THE CRUCIAL ROLE OF HISTONE MODIFICATION BY HDAC2 AND MECP2 COMPLEX FOR THE CONTROL OF GDNF EXPRESSION AND SUBSEQUENT BEHAVIORAL RESPONSES TO CHRONIC STRESS, IN OTHER WORDS, THE SUSCEPTIBILITY TO STRESS. IN ADDITION, WE INVESTIGATED THE EFFECT OF ANTIDEPRESSANTS ON THE EPIGENETIC REGULATION OF GDNF EXPRESSION. WE FOUND A REDUCED LEVEL OF HDAC4 RECRUITMENT AT THE GDNF PROMOTER REGION WITH ANTIDEPRESSANTS. THUS, OUR DATA SUGGEST THAT ANTIDEPRESSANTS INCREASE TRANSCRIPTIONAL ACTIVITY OF THE GDNF GENE THROUGH THE MODULATION OF HISTONE ACETYLATION BY HDAC4. FINALLY, WE EXAMINED THE EXPRESSIONS OF GDNF AND EPIGENETIC-RELATED MOLECULES MRNAS WITH MAJOR DEPRESSIVE AND BIPOLAR DISORDER PATIENTS BY USING QUANTITATIVE REAL-TIME PCR. WE FOUND THE ABERRANT EXPRESSION OF GDNF AND EPIGENETIC-RELATED GENES INCLUDING HDAC2 AND HDAC4 IN MOOD DISORDER PATIENTS. THUS, OUR DATA PROVIDE NOVEL INSIGHTS SUGGESTING THAT EPIGENETIC MECHANISMS OF GDNF EXPRESSION ARE INVOLVED IN THE PATHOGENESIS OR PATHOPHYSIOLOGY OF DEPRESSION.	2012	
                                                                                                                                                                                                                                                 
5 3080  49 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	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                
6 2442  28 EPIGENETIC STABILITY IN THE ADULT MOUSE CORTEX UNDER CONDITIONS OF PHARMACOLOGICALLY INDUCED HISTONE ACETYLATION. HISTONE ACETYLATION IS CONSIDERED A MAJOR EPIGENETIC PROCESS THAT AFFECTS BRAIN DEVELOPMENT AND SYNAPTIC PLASTICITY, AS WELL AS LEARNING AND MEMORY. THE TRANSCRIPTIONAL EFFECTORS AND MORPHOLOGICAL CHANGES RESPONSIBLE FOR PLASTICITY AS A RESULT OF LONG-TERM MODIFICATIONS TO HISTONE ACETYLATION ARE NOT FULLY UNDERSTOOD. TO THIS END, WE PHARMACOLOGICALLY INHIBITED HISTONE DEACETYLATION USING TRICHOSTATIN A IN ADULT (6-MONTH-OLD) MICE AND FOUND SIGNIFICANT INCREASES IN THE LEVELS OF THE ACETYLATED HISTONE MARKS H3LYS9, H3LYS14 AND H4LYS12. HIGH-RESOLUTION TRANSCRIPTOME ANALYSIS OF DIVERSE BRAIN REGIONS UNCOVERED FEW DIFFERENCES IN GENE EXPRESSION BETWEEN TREATED AND CONTROL ANIMALS, NONE OF WHICH WERE PLASTICITY RELATED. INSTEAD, AFTER INCREASED HISTONE ACETYLATION, WE DETECTED A LARGE NUMBER OF NOVEL TRANSCRIPTIONALLY ACTIVE REGIONS, WHICH CORRESPOND TO LONG NON-CODING RNAS (LNCRNAS). WE ALSO SURPRISINGLY FOUND NO SIGNIFICANT CHANGES IN DENDRITIC SPINE PLASTICITY IN LAYERS 1 AND 2/3 OF THE VISUAL CORTEX USING LONG-TERM IN VIVO TWO-PHOTON IMAGING. OUR RESULTS INDICATE THAT CHRONIC PHARMACOLOGICALLY INDUCED HISTONE ACETYLATION CAN BE DECOUPLED FROM GENE EXPRESSION AND INSTEAD, MAY POTENTIALLY EXERT A POST-TRANSCRIPTIONAL EFFECT THROUGH THE DIFFERENTIAL PRODUCTION OF LNCRNAS.	2016	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               
7 1186  37 COORDINATED DYNAMIC GENE EXPRESSION CHANGES IN THE CENTRAL NUCLEUS OF THE AMYGDALA DURING ALCOHOL WITHDRAWAL. BACKGROUND: CHRONIC ALCOHOL USE CAUSES WIDESPREAD CHANGES IN THE CELLULAR BIOLOGY OF THE AMYGDALA'S CENTRAL NUCLEUS (CEA), A GABAERGIC CENTER THAT INTEGRATES AUTONOMIC PHYSIOLOGY WITH THE EMOTIONAL ASPECTS OF MOTIVATION AND LEARNING. WHILE ALCOHOL-INDUCED NEUROCHEMICAL CHANGES PLAY A ROLE IN DEPENDENCE AND DRINKING BEHAVIOR, LITTLE IS KNOWN ABOUT THE CEA'S DYNAMIC CHANGES DURING WITHDRAWAL, A PERIOD OF EMOTIONAL AND PHYSIOLOGIC DISTURBANCE. METHODS: WE USED A QRT-PCR PLATFORM TO MEASURE 139 TRANSCRIPTS IN 92 RAT CEA SAMPLES FROM CONTROL (N = 33), CHRONICALLY ALCOHOL EXPOSED (N = 26), AND WITHDRAWN RATS (T = 4, 8, 18, 32, AND 48 HOURS; N = 5, 10, 7, 6, 5). THIS FOCUSED TRANSCRIPT SET ALLOWED US TO IDENTIFY SIGNIFICANT DYNAMIC EXPRESSION PATTERNS DURING THE FIRST 48 HOURS OF WITHDRAWAL AND PROPOSE POTENTIAL REGULATORY MECHANISMS. RESULTS: CHRONIC ALCOHOL EXPOSURE CAUSES A LIMITED NUMBER OF SMALL MAGNITUDE EXPRESSION CHANGES. IN CONTRAST, WITHDRAWAL RESULTS IN A GREATER NUMBER OF LARGE CHANGES WITHIN 4 HOURS OF REMOVAL OF THE ALCOHOL DIET. SIXTY-FIVE OF THE 139 MEASURED TRANSCRIPTS (47%) SHOWED DIFFERENTIAL REGULATION DURING WITHDRAWAL. OVER THE 48-HOUR PERIOD, DYNAMIC CHANGES IN THE EXPRESSION OF GAMMA-AMINOBUTYRIC ACID TYPE A (GABA(A) ), IONOTROPIC GLUTAMATE AND NEUROPEPTIDE SYSTEM-RELATED G-PROTEIN-COUPLED RECEPTOR SUBUNITS, AND THE RAS/RAF SIGNALING PATHWAY WERE SEEN AS WELL AS DOWNSTREAM TRANSCRIPTION FACTORS (TFS) AND EPIGENETIC REGULATORS. FOUR TEMPORALLY CORRELATED GENE CLUSTERS WERE IDENTIFIED WITH SHARED FUNCTIONAL ROLES INCLUDING NMDA RECEPTORS, MAPKKK AND CHEMOKINE SIGNALING CASCADES, AND MEDIATORS OF LONG-TERM POTENTIATION, AMONG OTHERS. CLUSTER PROMOTER REGIONS SHARED OVERREPRESENTED BINDING SITES FOR MULTIPLE TFS INCLUDING CEBP, USF-1, SMAD3, AP-2, AND C-ETS, SUGGESTING A POTENTIAL REGULATORY ROLE. CONCLUSIONS: DURING ALCOHOL WITHDRAWAL, THE CEA EXPERIENCES RAPID CHANGES IN MRNA EXPRESSION OF THESE FUNCTIONALLY RELATED TRANSCRIPTS THAT WERE NOT PREDICTED BY MEASUREMENT DURING CHRONIC EXPOSURE. THIS STUDY PROVIDES NEW INSIGHT INTO DYNAMIC EXPRESSION CHANGES DURING ALCOHOL WITHDRAWAL AND SUGGESTS NOVEL REGULATORY RELATIONSHIPS THAT POTENTIALLY IMPACT THE ASPECTS OF EMOTIONAL MODULATION.	2013	
                                                                                                                                                                                                                                                                                                                                                                  
8 2297  31 EPIGENETIC REGULATION OF ACUTE INFLAMMATORY PAIN. ACUTE PAIN IS ASSOCIATED WITH TISSUE DAMAGE, WHICH RESULTS IN THE RELEASE OF INFLAMMATORY MEDIATORS. RECENT STUDIES POINT TO THE INVOLVEMENT OF EPIGENETIC MECHANISMS (DNA METHYLATION) IN THE DEVELOPMENT OF PAIN. WE HAVE FOUND THAT DURING ACUTE INFLAMMATORY PAIN INDUCED BY THE APPLICATION OF 10% MUSTARD OIL ON THE TONGUES OF RATS, LEVELS OF DNMT3A AND 3B WERE ELEVATED MARKEDLY (36 AND 42 % RESPECTIVELY), WHEREAS THE LEVEL OF DNMT1 WAS NOT CHANGED SIGNIFICANTLY. PREVIOUS INJECTION OF XEFOCAM WITH 0,4 MG/KG DOSE DECREASED LEVELS OF DNMT3A AND 3B (25 AND 24% RESPECTIVELY). THE LEVEL OF DNMT1 WAS NOT CHANGED SIGNIFICANTLY COMPARED TO THE CONTROL GROUP. THE FINDINGS SUPPORT THE IDEA THAT INHIBITORS OF DNA-METHYLTRANSFERASES COULD BE USEFUL FOR PAIN MANAGEMENT. OUR DATA SUGGEST THAT NSAIDS (ALONE OR IN COMBINATION WITH DNMT INHIBITORS) MAY BE PROPOSED AS POSSIBLE EPIGENETIC REGULATORY AGENTS, WHICH MAY PLAY A ROLE IN EPIGENETIC MECHANISMS INDIRECTLY THROUGH ALTERING THE ACTIVITY OF INFLAMMATORY MEDIATORS INVOLVED IN PAIN DEVELOPMENT.	2014	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       
9 5177  45 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	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   
10 1875  62 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	
                                                                                                                                                                                                                                                                                                                                            
11  433  39 ANTIDEPRESSANT TREATMENT IS ASSOCIATED WITH EPIGENETIC ALTERATIONS OF HOMER1 PROMOTER IN A MOUSE MODEL OF CHRONIC DEPRESSION. BACKGROUND: UNDERSTANDING THE NEUROBIOLOGY OF DEPRESSION AND THE MECHANISM OF ACTION OF THERAPEUTIC MEASURES IS CURRENTLY A RESEARCH PRIORITY. WE HAVE SHOWN THAT THE EXPRESSION OF THE SYNAPTIC PROTEIN HOMER1A CORRELATES WITH DEPRESSION-LIKE BEHAVIOR AND ITS INDUCTION IS A COMMON MECHANISM OF ACTION OF DIFFERENT ANTIDEPRESSANT TREATMENTS. HOWEVER, THE MECHANISM OF HOMER1A REGULATION IS STILL UNKNOWN. METHODS: WE COMBINED THE CHRONIC DESPAIR MOUSE MODEL (CDM) OF CHRONIC DEPRESSION WITH DIFFERENT ANTIDEPRESSANT TREATMENTS. DEPRESSION-LIKE BEHAVIOR WAS CHARACTERIZED BY FORCED SWIM AND TAIL SUSPENSION TESTS, AND VIA AUTOMATIC MEASUREMENT OF SUCROSE PREFERENCE IN INTELLICAGE. THE HOMER1 MRNA EXPRESSION AND PROMOTER DNA METHYLATION WERE ANALYZED IN CORTEX AND PERIPHERAL BLOOD BY QRT-PCR AND PYROSEQUENCING. RESULTS: CDM MICE SHOW DECREASED HOMER1A AND HOMER1B/C MRNA EXPRESSION IN CORTEX AND BLOOD SAMPLES, WHILE CHRONIC TREATMENT WITH IMIPRAMINE AND FLUOXETINE OR ACUTE KETAMINE APPLICATION INCREASES THEIR LEVEL ONLY IN THE CORTEX. THE QUANTITATIVE ANALYSES OF THE METHYLATION OF 7 CPG SITES, LOCATED ON THE HOMER1 PROMOTER REGION CONTAINING SEVERAL CRE BINDING SITES, SHOW A SIGNIFICANT INCREASE IN DNA METHYLATION IN THE CORTEX OF CDM MICE. IN CONTRAST, ANTIDEPRESSANT TREATMENTS REDUCE THE METHYLATION LEVEL. LIMITATIONS: HOMER1 EXPRESSION AND PROMOTOR METHYLATION WERE NOT ANALYZED IN DIFFERENT BLOOD CELL TYPES. OTHER CPG SITES OF HOMER1 PROMOTER SHOULD BE INVESTIGATED IN FUTURE STUDIES. OUR EXPERIMENTAL APPROACH DOES NOT DISTINGUISH BETWEEN METHYLATION AND HYDROXYMETHYLATION. CONCLUSIONS: WE DEMONSTRATE THAT STRESS-INDUCED DEPRESSION-LIKE BEHAVIOR AND ANTIDEPRESSANT TREATMENTS ARE ASSOCIATED WITH EPIGENETIC ALTERATIONS OF HOMER1 PROMOTER, PROVIDING NEW INSIGHTS INTO THE MECHANISM OF ANTIDEPRESSANT TREATMENT.	2021	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         
12 6411  47 THE SITE SPECIFIC DEMETHYLATION IN THE 5'-REGULATORY AREA OF NMDA RECEPTOR 2B SUBUNIT GENE ASSOCIATED WITH CIE-INDUCED UP-REGULATION OF TRANSCRIPTION. BACKGROUND: THE NMDA RECEPTOR REPRESENTS A PARTICULARLY IMPORTANT SITE OF ETHANOL ACTION IN THE CNS. WE RECENTLY REPORTED THAT NMDA RECEPTOR 2B (NR2B) GENE EXPRESSION WAS PERSISTENTLY UP-REGULATED FOLLOWING CHRONIC INTERMITTENT ETHANOL (CIE) TREATMENT. INCREASING EVIDENCE THAT EPIGENETIC MECHANISMS ARE INVOLVED IN DYNAMIC AND LONG-LASTING REGULATION OF GENE EXPRESSION IN MULTIPLE NEUROADAPTIVE PROCESSES PROMPTED US TO INVESTIGATE THE ROLE OF DNA METHYLATION IN MEDIATING CIE-INDUCED UP-REGULATION OF NR2B GENE TRANSCRIPTION. TO DISSECT THE CHANGES OF DNA METHYLATION IN THE NR2B GENE, WE HAVE SCREENED A LARGE NUMBER OF CPG SITES WITHIN ITS 5'-REGULATORY AREA FOLLOWING CIE TREATMENT. METHODS: PRIMARY CORTICAL CULTURED NEURONS WERE SUBJECTED TO ETHANOL TREATMENT IN A CIE PARADIGM. BISULFITE CONVERSION FOLLOWED BY PYROSEQUENCING WAS USED FOR QUANTITATIVE MEASUREMENT AND ANALYSIS OF CPG METHYLATION STATUS WITHIN THE 5'-REGULATORY AREA OF THE NR2B GENE; CHROMATIN IMMUNOPRECIPITATION (CHIP) ASSAY WAS USED TO EXAMINE DNA LEVELS ASSOCIATED WITH METHYLATION AND TRANSCRIPTION FACTOR BINDING. ELECTROPHORETIC MOBILITY SHIFT ASSAY (EMSA) AND IN VITRO DNA METHYLATION ASSAYS WERE PERFORMED TO DETERMINE THE DIRECT IMPACT OF DNA METHYLATION ON THE INTERACTION BETWEEN DNA AND TRANSCRIPTION FACTOR AND PROMOTER ACTIVITY. RESULTS: ANALYSIS OF INDIVIDUAL CPG METHYLATION SITES WITHIN THE NR2B 5'REGULATORY AREA REVEALED THREE REGIONS WITH CLUSTERS OF SITE-SPECIFIC CPG DEMETHYLATION FOLLOWING CIE TREATMENT AND WITHDRAWAL. THIS WAS CONFIRMED BY CHIP SHOWING SIMILAR DECREASES OF METHYLATED DNA IN THE SAME REGIONS. THE CIE-INDUCED DEMETHYLATION IS CHARACTERIZED BY BEING LOCATED NEAR CERTAIN TRANSCRIPTION FACTOR BINDING SEQUENCES, AP-1 AND CRE, AND OCCURRED DURING TREATMENT AS WELL AS AFTER ETHANOL WITHDRAWAL. FURTHERMORE, THE INCREASE IN VITRO OF METHYLATED DNA DECREASED TRANSCRIPTION FACTOR BINDING ACTIVITY AND PROMOTER ACTIVITY. AN ADDITIONAL CHIP ASSAY INDICATED THAT THE CIE-INDUCED DNA DEMETHYLATION IS ACCOMPANIED BY INCREASED OCCUPATION BY TRANSCRIPTION FACTORS. CONCLUSIONS: THESE RESULTS SUGGEST AN IMPORTANT ROLE OF DNA DEMETHYLATION IN MEDIATING CIE-INDUCED NR2B GENE UP-REGULATION, THUS IMPLICATING A NOVEL MOLECULAR SITE OF ALCOHOL ACTION.	2010	
                                                                                                                                                                                                                                                                                                    
13 4405  39 MOLECULAR ADAPTATIONS OF THE BLOOD-BRAIN BARRIER PROMOTE STRESS RESILIENCE VS. DEPRESSION. PRECLINICAL AND CLINICAL STUDIES SUGGEST THAT INFLAMMATION AND VASCULAR DYSFUNCTION CONTRIBUTE TO THE PATHOGENESIS OF MAJOR DEPRESSIVE DISORDER (MDD). CHRONIC SOCIAL STRESS ALTERS BLOOD-BRAIN BARRIER (BBB) INTEGRITY THROUGH LOSS OF TIGHT JUNCTION PROTEIN CLAUDIN-5 (CLDN5) IN MALE MICE, PROMOTING PASSAGE OF CIRCULATING PROINFLAMMATORY CYTOKINES AND DEPRESSION-LIKE BEHAVIORS. THIS EFFECT IS PROMINENT WITHIN THE NUCLEUS ACCUMBENS, A BRAIN REGION ASSOCIATED WITH MOOD REGULATION; HOWEVER, THE MECHANISMS INVOLVED ARE UNCLEAR. MOREOVER, COMPENSATORY RESPONSES LEADING TO PROPER BEHAVIORAL STRATEGIES AND ACTIVE RESILIENCE ARE UNKNOWN. HERE WE IDENTIFY ACTIVE MOLECULAR CHANGES WITHIN THE BBB ASSOCIATED WITH STRESS RESILIENCE THAT MIGHT SERVE A PROTECTIVE ROLE FOR THE NEUROVASCULATURE. WE ALSO CONFIRM THE RELEVANCE OF SUCH CHANGES TO HUMAN DEPRESSION AND ANTIDEPRESSANT TREATMENT. WE SHOW THAT PERMISSIVE EPIGENETIC REGULATION OF CLDN5 EXPRESSION AND LOW ENDOTHELIUM EXPRESSION OF REPRESSIVE CLDN5-RELATED TRANSCRIPTION FACTOR FOXO1 ARE ASSOCIATED WITH STRESS RESILIENCE. REGION- AND ENDOTHELIAL CELL-SPECIFIC WHOLE TRANSCRIPTOMIC ANALYSES REVEALED MOLECULAR SIGNATURES ASSOCIATED WITH STRESS VULNERABILITY VS. RESILIENCE. WE IDENTIFIED PROINFLAMMATORY TNFALPHA/NFKAPPAB SIGNALING AND HDAC1 AS MEDIATORS OF STRESS SUSCEPTIBILITY. PHARMACOLOGICAL INHIBITION OF STRESS-INDUCED INCREASE IN HDAC1 ACTIVITY RESCUED CLDN5 EXPRESSION IN THE NAC AND PROMOTED RESILIENCE. IMPORTANTLY, WE CONFIRMED CHANGES IN HDAC1 EXPRESSION IN THE NAC OF DEPRESSED PATIENTS WITHOUT ANTIDEPRESSANT TREATMENT IN LINE WITH CLDN5 LOSS. CONVERSELY, MANY OF THESE DELETERIOUS CLDN5-RELATED MOLECULAR CHANGES WERE REDUCED IN POSTMORTEM NAC FROM ANTIDEPRESSANT-TREATED SUBJECTS. THESE FINDINGS REINFORCE THE IMPORTANCE OF CONSIDERING STRESS-INDUCED NEUROVASCULAR PATHOLOGY IN DEPRESSION AND PROVIDE THERAPEUTIC TARGETS TO TREAT THIS MOOD DISORDER AND PROMOTE RESILIENCE.	2020	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            
14 5273  38 PROMOTER METHYLATION AND BDNF AND DAT1 GENE EXPRESSION PROFILES IN PATIENTS WITH DRUG ADDICTION. BACKGROUND: DRUG ADDICTION IS A BRAIN DISORDER THAT HAS NEGATIVE CONSEQUENCES FOR INDIVIDUALS AND SOCIETY. ADDICTIONS ARE CHRONIC RELAPSING DISEASES OF THE BRAIN THAT ARE CAUSED BY DIRECT DRUG-INDUCED EFFECTS AND PERSEVERING NEUROADAPTATIONS AT THE EPIGENETIC, NEUROPEPTIDE AND NEUROTRANSMITTER LEVELS. BECAUSE THE DOPAMINERGIC SYSTEM HAS A SIGNIFICANT ROLE IN DRUG ABUSE, THE PURPOSE OF THIS STUDY WAS TO ANALYZE THE METHYLATION AND EXPRESSION PROFILE OF BRAIN-DERIVED NEUROTROPHIC FACTOR (BDNF) AND DOPAMINE TRANSPORTER (DAT1) GENES IN INDIVIDUALS WITH DRUG ADDICTION. MATERIALS AND METHODS: BDNF AND DAT1 PROMOTER METHYLATION WERE INVESTIGATED WITH A METHYLATION-SPECIFIC POLYMERASE CHAIN REACTION (PCR) TECHNIQUE IN BLOOD SAMPLES FROM 75 INDIVIDUALS WITH DRUG ADDICTION AND 65 HEALTHY CONTROLS. THE EXPRESSION LEVELS OF BDNF AND DAT1 WERE ASSESSED IN 12 MRNA SAMPLES FROM THE BLOOD OF PATIENTS AND COMPARED TO THE SAMPLES OF HEALTHY CONTROLS (N = 12) WITH REAL-TIME QUANTITATIVE REVERSE TRANSCRIPTION PCR. RESULTS: NO SIGNIFICANT DIFFERENCES WERE FOUND IN THE METHYLATION OF BDNF AND DAT1 BETWEEN PATIENTS AND CONTROLS, BUT THE RELATIVE LEVELS OF EXPRESSION OF BDNF AND DAT1 MRNA DIFFERED SIGNIFICANTLY IN THE PATIENTS COMPARED TO CONTROLS (P < 0.0001). CONCLUSION: THESE RESULTS SHOWED THAT THE METHYLATION STATUS OF THE BDNF AND DAT1 GENES HAD NO SIGNIFICANT FUNCTION IN THE PROCESSES OF DRUG ADDICTION.	2015	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        
15 2625  39 EPIGENOME-WIDE ASSOCIATION STUDY AND MULTI-TISSUE REPLICATION OF INDIVIDUALS WITH ALCOHOL USE DISORDER: EVIDENCE FOR ABNORMAL GLUCOCORTICOID SIGNALING PATHWAY GENE REGULATION. ALCOHOL USE DISORDER (AUD) IS A CHRONIC DEBILITATING DISORDER WITH LIMITED TREATMENT OPTIONS AND POORLY DEFINED PATHOPHYSIOLOGY. THERE ARE SUBSTANTIAL GENETIC AND EPIGENETIC COMPONENTS; HOWEVER, THE UNDERLYING MECHANISMS CONTRIBUTING TO AUD REMAIN LARGELY UNKNOWN. WE CONDUCTED THE LARGEST DNA METHYLATION EPIGENOME-WIDE ASSOCIATION STUDY (EWAS) ANALYSES CURRENTLY AVAILABLE FOR AUD (TOTAL N = 625) AND EMPLOYED A TOP HIT REPLICATION (N = 4798) USING A CROSS-TISSUE/CROSS-PHENOTYPIC APPROACH WITH THE GOAL OF IDENTIFYING NOVEL EPIGENETIC TARGETS RELEVANT TO AUD. RESULTS SHOW THAT A NETWORK OF DIFFERENTIALLY METHYLATED REGIONS IN GLUCOCORTICOID SIGNALING AND INFLAMMATION-RELATED GENES WERE ASSOCIATED WITH ALCOHOL USE BEHAVIORS. A TOP PROBE CONSISTENTLY ASSOCIATED ACROSS ALL COHORTS WAS LOCATED IN THE LONG NON-CODING RNA GROWTH ARREST SPECIFIC FIVE GENE (GAS5) (P < 10(-24)). GAS5 HAS BEEN IMPLICATED IN REGULATING TRANSCRIPTIONAL ACTIVITY OF THE GLUCOCORTICOID RECEPTOR AND HAS MULTIPLE FUNCTIONS RELATED TO APOPTOSIS, IMMUNE FUNCTION AND VARIOUS CANCERS. ENDOPHENOTYPIC ANALYSES USING PERIPHERAL CORTISOL LEVELS AND NEUROIMAGING PARADIGMS SHOWED THAT METHYLOMIC VARIATION IN GAS5 NETWORK-RELATED PROBES WERE ASSOCIATED WITH STRESS PHENOTYPES. POSTMORTEM BRAIN ANALYSES DOCUMENTED INCREASED GAS5 EXPRESSION IN THE AMYGDALA OF INDIVIDUALS WITH AUD. OUR DATA SUGGEST THAT ALCOHOL USE IS ASSOCIATED WITH DIFFERENTIAL METHYLATION IN THE GLUCOCORTICOID SYSTEM THAT MIGHT INFLUENCE STRESS AND INFLAMMATORY REACTIVITY AND SUBSEQUENTLY RISK FOR AUD.	2021	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                
16  345  43 ALTERED BRAIN EXPRESSION OF DNA METHYLATION AND HYDROXYMETHYLATION EPIGENETIC ENZYMES IN A RAT MODEL OF NEUROPATHIC PAIN. THE ROLE OF EPIGENETICS IN CHRONIC PAIN AT THE SUPRASPINAL LEVEL IS YET TO BE FULLY CHARACTERIZED. DNA HISTONE METHYLATION IS CRUCIALLY REGULATED BY DE NOVO METHYLTRANSFERASES (DNMT1-3) AND TEN-ELEVEN TRANSLOCATION DIOXYGENASES (TET1-3). EVIDENCE HAS SHOWN THAT METHYLATION MARKERS ARE ALTERED IN DIFFERENT CNS REGIONS RELATED TO NOCICEPTION, NAMELY THE DORSAL ROOT GANGLIA, THE SPINAL CORD, AND DIFFERENT BRAIN AREAS. DECREASED GLOBAL METHYLATION WAS FOUND IN THE DRG, THE PREFRONTAL CORTEX, AND THE AMYGDALA, WHICH WAS ASSOCIATED WITH DECREASED DNMT1/3A EXPRESSION. IN CONTRAST, INCREASED METHYLATION LEVELS AND MRNA LEVELS OF TET1 AND TET3 WERE LINKED TO AUGMENTED PAIN HYPERSENSITIVITY AND ALLODYNIA IN INFLAMMATORY AND NEUROPATHIC PAIN MODELS. SINCE EPIGENETIC MECHANISMS MAY BE RESPONSIBLE FOR THE REGULATION AND COORDINATION OF VARIOUS TRANSCRIPTIONAL MODIFICATIONS DESCRIBED IN CHRONIC PAIN STATES, WITH THIS STUDY, WE AIMED TO EVALUATE THE FUNCTIONAL ROLE OF TET1-3 AND DNMT1/3A GENES IN NEUROPATHIC PAIN IN SEVERAL BRAIN AREAS. IN A SPARED NERVE INJURY RAT MODEL OF NEUROPATHIC PAIN, 21 DAYS AFTER SURGERY, WE FOUND INCREASED TET1 EXPRESSION IN THE MEDIAL PREFRONTAL CORTEX AND DECREASED EXPRESSION IN THE CAUDATE-PUTAMEN AND THE AMYGDALA; TET2 WAS UPREGULATED IN THE MEDIAL THALAMUS; TET3 MRNA LEVELS WERE REDUCED IN THE MEDIAL PREFRONTAL CORTEX AND THE CAUDATE-PUTAMEN; AND DNMT1 WAS DOWNREGULATED IN THE CAUDATE-PUTAMEN AND THE MEDIAL THALAMUS. NO STATISTICALLY SIGNIFICANT CHANGES IN EXPRESSION WERE OBSERVED WITH DNMT3A. OUR RESULTS SUGGEST A COMPLEX FUNCTIONAL ROLE FOR THESE GENES IN DIFFERENT BRAIN AREAS IN THE CONTEXT OF NEUROPATHIC PAIN. THE NOTION OF DNA METHYLATION AND HYDROXYMETHYLATION BEING CELL-TYPE SPECIFIC AND NOT TISSUE SPECIFIC, AS WELL AS THE POSSIBILITY OF CHRONOLOGICALLY DIFFERENTIAL GENE EXPRESSION AFTER THE ESTABLISHMENT OF NEUROPATHIC OR INFLAMMATORY PAIN MODELS, OUGHT TO BE ADDRESSED IN FUTURE STUDIES.	2023	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       
17 1903  46 ENHANCED NEUROINFLAMMATION MEDIATED BY DNA METHYLATION OF THE GLUCOCORTICOID RECEPTOR TRIGGERS COGNITIVE DYSFUNCTION AFTER SEVOFLURANE ANESTHESIA IN ADULT RATS SUBJECTED TO MATERNAL SEPARATION DURING THE NEONATAL PERIOD. BACKGROUND: MOUNTING EVIDENCE INDICATES THAT CHILDREN WHO EXPERIENCE ABUSE AND NEGLECT ARE PRONE TO CHRONIC DISEASES AND PREMATURE MORTALITY LATER IN LIFE. ONE MECHANISTIC HYPOTHESIS FOR THIS PHENOMENON IS THAT EARLY LIFE ADVERSITY ALTERS THE EXPRESSION OR FUNCTIONING OF THE GLUCOCORTICOID RECEPTOR (GR) THROUGHOUT THE COURSE OF LIFE AND THEREBY INCREASES SENSITIVITY TO INFLAMMATORY STIMULATION. AN EXAGGERATED PRO-INFLAMMATORY RESPONSE IS GENERALLY CONSIDERED TO BE A KEY CAUSE OF POSTOPERATIVE COGNITIVE DYSFUNCTION (POCD). THE AIM OF THIS STUDY WAS TO EXAMINE THE EFFECTS OF EARLY LIFE ADVERSITY ON COGNITIVE FUNCTION AND NEUROINFLAMMATION AFTER SEVOFLURANE ANESTHESIA IN ADULT RATS AND TO DETERMINE WHETHER SUCH EFFECTS ARE ASSOCIATED WITH THE EPIGENETIC REGULATION OF GR. METHODS: WISTAR RAT PUPS WERE REPEATEDLY SUBJECTED TO INFANT MATERNAL SEPARATION (EARLY LIFE STRESS) FROM POSTNATAL DAYS 2-21. IN ADULTHOOD, THEIR BEHAVIOR AND THE SIGNALING OF HIPPOCAMPAL PRO-INFLAMMATORY FACTORS AND NUCLEAR FACTOR-KAPPA B (NF-KAPPAB) AFTER SEVOFLURANE ANESTHESIA WERE EVALUATED. WE ALSO EXAMINED THE EFFECTS OF MATERNAL SEPARATION (MS) ON THE EXPRESSION OF GR AND THE DNA METHYLATION STATUS OF THE PROMOTER REGION OF EXON 1(7) OF GR AND WHETHER BEHAVIORAL CHANGES AND NEUROINFLAMMATION AFTER ANESTHESIA WERE REVERSIBLE WHEN THE EXPRESSION OF GR WAS INCREASED BY ALTERING DNA METHYLATION. RESULTS: MS INDUCED COGNITIVE DECLINE AFTER SEVOFLURANE INHALATION IN THE MORRIS WATER MAZE AND CONTEXT FEAR CONDITIONING TESTS AND ENHANCED THE RELEASE OF CYTOKINES AND THE ACTIVATION OF ASTROCYTE INTRACELLULAR NF-KAPPAB SIGNALING INDUCED BY SEVOFLURANE IN THE HIPPOCAMPUS OF ADULT RATS. BLOCKING NF-KAPPAB SIGNALING BY PYRROLIDINE DITHIOCARBAMATE (PDTC) INHIBITED THE RELEASE OF CYTOKINES. MS ALSO REDUCED THE EXPRESSION OF GR AND UPREGULATED THE METHYLATION LEVELS OF THE PROMOTER REGION OF GR EXON 1(7), AND SUCH EFFECTS WERE REVERSED BY TREATMENT WITH THE HISTONE DEACETYLASE INHIBITOR TRICHOSTATIN A (TSA) IN ADULT RATS. MOREOVER, TSA TREATMENT IN ADULT MS RATS INHIBITED THE OVERACTIVATION OF ASTROCYTE INTRACELLULAR NF-KAPPAB SIGNALING AND THE RELEASE OF CYTOKINES AND ALLEVIATED COGNITIVE DYSFUNCTION AFTER SEVOFLURANE ANESTHESIA. CONCLUSIONS: EARLY LIFE STRESS INDUCES COGNITIVE DYSFUNCTION AFTER SEVOFLURANE ANESTHESIA, PERHAPS DUE TO THE ABERRANT METHYLATION OF THE GR GENE PROMOTER, WHICH REDUCES THE EXPRESSION OF THE GR GENE AND FACILITATES EXAGGERATED INFLAMMATORY RESPONSES.	2017	

18 5065  32 PHOTOPERIOD-INDUCED NEUROTRANSMITTER PLASTICITY DECLINES WITH AGING: AN EPIGENETIC REGULATION? NEUROPLASTICITY HAS CLASSICALLY BEEN UNDERSTOOD TO ARISE THROUGH CHANGES IN SYNAPTIC STRENGTH OR SYNAPTIC CONNECTIVITY. A NEWLY DISCOVERED FORM OF NEUROPLASTICITY, NEUROTRANSMITTER SWITCHING, INVOLVES CHANGES IN NEUROTRANSMITTER IDENTITY. CHRONIC EXPOSURE TO DIFFERENT PHOTOPERIODS ALTERS THE NUMBER OF DOPAMINE (TYROSINE HYDROXYLASE, TH+) AND SOMATOSTATIN (SST+) NEURONS IN THE PARAVENTRICULAR NUCLEUS (PAVN) OF THE HYPOTHALAMUS OF ADULT RATS AND RESULTS IN DISCRETE BEHAVIORAL CHANGES. HERE, WE INVESTIGATE WHETHER PHOTOPERIOD-INDUCED NEUROTRANSMITTER SWITCHING PERSISTS DURING AGING AND WHETHER EPIGENETIC MECHANISMS OF HISTONE ACETYLATION AND DNA METHYLATION MAY CONTRIBUTE TO THIS NEUROTRANSMITTER PLASTICITY. WE SHOW THAT THIS PLASTICITY IN RATS IS ROBUST AT 1 AND AT 3 MONTHS BUT REDUCED IN TH+ NEURONS AT 12 MONTHS AND COMPLETELY ABOLISHED IN BOTH TH+ AND SST+ NEURONS BY 18 MONTHS. DE NOVO EXPRESSION OF DNMT3A CATALYZING DNA METHYLATION AND ANTI-ACETYLH3 ASSESSING HISTONE 3 ACETYLATION WERE OBSERVED FOLLOWING SHORT-DAY PHOTOPERIOD EXPOSURE IN BOTH TH+ AND SST+ NEURONS AT 1 AND 3 MONTHS WHILE AN OVERALL INCREASE IN DNMT3A IN SST+ NEURONS PARALLELED NEUROPLASTICITY REDUCTION AT 12 AND 18 MONTHS. HISTONE ACETYLATION INCREASED IN TH+ NEURONS AND DECREASED IN SST+ NEURONS FOLLOWING SHORT-DAY EXPOSURE AT 3 MONTHS WHILE THE TOTAL NUMBER OF ANTI-ACETYLH3+ PAVN NEURONS REMAINED CONSTANT. RECIPROCAL HISTONE ACETYLATION IN TH+ AND SST+ NEURONS INDICATES THE IMPORTANCE OF STUDYING EPIGENETIC REGULATION AT THE CIRCUIT LEVEL FOR IDENTIFIED CELL PHENOTYPES. THE FINDINGS MAY BE USEFUL FOR DEVELOPING APPROACHES FOR NONINVASIVE TREATMENT OF DISORDERS CHARACTERIZED BY NEUROTRANSMITTER DYSFUNCTION.	2020	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    
19 2089  37 EPIGENETIC DYSREGULATION OF THE DOPAMINE SYSTEM IN DIET-INDUCED OBESITY. CHRONIC INTAKE OF HIGH-FAT (HF) DIET IS KNOWN TO ALTER BRAIN NEUROTRANSMITTER SYSTEMS THAT PARTICIPATE IN THE CENTRAL REGULATION OF FOOD INTAKE. DOPAMINE (DA) SYSTEM CHANGES IN RESPONSE TO HF DIET HAVE BEEN OBSERVED IN THE HYPOTHALAMUS, IMPORTANT IN THE HOMEOSTATIC CONTROL OF FOOD INTAKE, AS WELL AS WITHIN THE CENTRAL REWARD CIRCUITRY [VENTRAL TEGMENTAL AREA (VTA), NUCLEUS ACCUMBENS (NAC), AND PRE-FRONTAL CORTEX (PFC)], CRITICAL FOR CODING THE REWARDING PROPERTIES OF PALATABLE FOOD AND IMPORTANT IN HEDONICALLY DRIVEN FEEDING BEHAVIOR. USING A MOUSE MODEL OF DIET-INDUCED OBESITY (DIO), SIGNIFICANT ALTERATIONS IN THE EXPRESSION OF DA-RELATED GENES WERE DOCUMENTED IN ADULT ANIMALS, AND THE GENERAL PATTERN OF GENE EXPRESSION CHANGES WAS OPPOSITE WITHIN THE HYPOTHALAMUS VERSUS THE REWARD CIRCUITRY (INCREASED VS. DECREASED, RESPECTIVELY). DIFFERENTIAL DNA METHYLATION WAS IDENTIFIED WITHIN THE PROMOTER REGIONS OF TYROSINE HYDROXYLASE (TH) AND DOPAMINE TRANSPORTER (DAT), AND THE PATTERN OF THIS RESPONSE WAS CONSISTENT WITH THE PATTERN OF GENE EXPRESSION. BEHAVIORS CONSISTENT WITH INCREASED HYPOTHALAMIC DA AND DECREASED REWARD CIRCUITRY DA WERE OBSERVED. THESE DATA IDENTIFY DIFFERENTIAL DNA METHYLATION AS AN EPIGENETIC MECHANISM LINKING THE CHRONIC INTAKE OF HF DIET WITH ALTERED DA-RELATED GENE EXPRESSION, AND THIS RESPONSE VARIES BY BRAIN REGION AND DNA SEQUENCE.	2012	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                
20 1418  41 DIFFERENCES IN DNA METHYLATION REPROGRAMMING UNDERLIE THE SEXUAL DIMORPHISM OF BEHAVIORAL DISORDER CAUSED BY PRENATAL STRESS IN RATS. PRENATAL STRESS (PS) CAN LEAD TO NEUROENDOCRINE AND EMOTIONAL DISORDERS LATER IN ADOLESCENCE. SEXUAL DIMORPHISM IN THESE NEURODEVELOPMENTAL OUTCOMES HAVE BEEN OBSERVED; HOWEVER, THE UNDERLYING MECHANISMS ARE NOT FULLY UNDERSTOOD. TO ADDRESS THIS ISSUE, WE INVESTIGATED WHETHER THERE ARE SEX DIFFERENCES IN EPIGENETIC REPROGRAMMING IN RATS EXPOSED TO PS. PREGNANT FEMALE RATS WERE SUBJECTED TO CHRONIC RESTRAINT STRESS FROM GESTATIONAL DAY (G)12 TO G18. FROM POSTNATAL DAY (P)38 TO P45, SUBGROUPS OF OFFSPRING INCLUDING BOTH MALES AND FEMALES WERE SUBJECTED TO BEHAVIORAL TESTING AND BRAIN TISSUE SPECIMENS WERE ANALYZED BY DNA PYROSEQUENCING, WESTERN BLOTTING, AND GOLGI STAINING TO ASSESS CHANGES IN METHYLATION PATTERN OF GLUCOCORTICOID RECEPTOR (GR) GENE, EXPRESSION OF DNA METHYLTRANSFERASE (DNMT) AND DNA DEMETHYLASE, AND DENDRITE MORPHOLOGY, RESPECTIVELY. THE DNA METHYLTRANSFERASE INHIBITOR DECITABINE WAS ADMINISTERED TO RATS PRIOR TO PS TO FURTHER EVALUATE THE ROLE OF METHYLATION IN THE SEXUALLY DIMORPHIC EFFECTS OF PS. THE RESULTS SHOWED THAT PS INCREASED ANXIETY-LIKE BEHAVIOR IN OFFSPRING, ESPECIALLY IN FEMALES, WHILE DEPRESSION-LIKE BEHAVIOR WAS INCREASED IN MALE OFFSPRING COMPARED TO CONTROL LITTERMATES. THE METHYLATION PATTERN IN THE PROMOTER REGION OF THE GR GENE DIFFERED BETWEEN MALES AND FEMALES. SEX-SPECIFIC CHANGES IN THE EXPRESSION OF DNMTS (DNMT1 AND DNMT3A) AND DNA DEMETHYLASE (TET METHYLCYTOSINE DIOXYGENASE 2) WERE ALSO OBSERVED. INTERESTINGLY, DECITABINE ALLEVIATED THE BEHAVIORAL DISORDER CAUSED BY PS AND RESTORED DENDRITE DENSITY AND MORPHOLOGY IN FEMALE BUT NOT MALE RATS. THESE FINDINGS SUGGEST THAT DIFFERENT CHANGE PATTERNS OF DNMT AND DEMETHYLASE IN THE TWO SEXES AFTER PS ARE RESPONSIBLE FOR THE SEXUALLY DIMORPHISM, WHICH COULD HAVE IMPLICATIONS FOR THE CLINICAL MANAGEMENT OF STRESS-RELATED DISORDERS.	2020