1 513 124 ASSOCIATION OF SEROTONIN TRANSPORTER GENE ALUJB METHYLATION WITH MAJOR DEPRESSION, AMYGDALA RESPONSIVENESS, 5-HTTLPR/RS25531 POLYMORPHISM, AND STRESS. DNA METHYLATION PROFILES OF THE SEROTONIN TRANSPORTER GENE (SLC6A4) HAVE BEEN SHOWN TO ALTER SLC6A4 EXPRESSION, DRIVE ANTIDEPRESSANT TREATMENT RESPONSE AND MODIFY BRAIN FUNCTIONS. THIS STUDY INVESTIGATED WHETHER METHYLATION OF AN ALUJB ELEMENT IN THE SLC6A4 PROMOTOR WAS ASSOCIATED WITH MAJOR DEPRESSIVE DISORDER (MDD), AMYGDALA REACTIVITY TO EMOTIONAL FACES, 5-HTTLPR/RS25531 POLYMORPHISM, AND RECENT STRESS. MDD PATIENTS (N=122) AND HEALTHY CONTROLS (HC, N=176) UNDERWENT FMRI DURING AN EMOTIONAL FACE-MATCHING TASK. INDIVIDUAL SLC6A4 ALUJB METHYLATION PROFILES WERE ASCERTAINED AND ASSOCIATED WITH MDD, AMYGDALA REACTIVITY, 5-HTTLPR/RS25531, AND STRESS. SLC6A4 ALUJB METHYLATION WAS SIGNIFICANTLY LOWER IN MDD COMPARED TO HC AND IN STRESSED COMPARED TO LESS STRESSED PARTICIPANTS. LOWER ALUJB METHYLATION WAS PARTICULARLY FOUND IN 5-HTTLPR/RS25531 RISK ALLELE CARRIERS UNDER STRESS AND CORRELATED WITH LESS DEPRESSIVE EPISODES. FMRI ANALYSIS REVEALED A SIGNIFICANT INTERACTION OF ALUJB METHYLATION AND DIAGNOSIS IN THE AMYGDALA, WITH MDD PATIENTS SHOWING LOWER ALUJB METHYLATION ASSOCIATED WITH DECREASED AMYGDALA REACTIVITY. WHILE NO JOINT EFFECT OF ALUJB METHYLATION AND 5-HTTLPR/RS25531 EXISTED, RISK ALLELE CARRIERS SHOWED SIGNIFICANTLY INCREASED BILATERAL AMYGDALA ACTIVATION. THESE FINDINGS SUGGEST A ROLE OF SLC6A4 ALUJB METHYLATION IN MDD, AMYGDALA REACTIVITY, AND STRESS REACTION, PARTLY INTERWOVEN WITH 5-HTTLPR/RS25531 EFFECTS. PATIENTS WITH LOW METHYLATION IN CONJUNCTION WITH A SHORTER MDD HISTORY AND DECREASED AMYGDALA REACTIVITY MIGHT FEATURE A MORE STRESS-ADAPTIVE EPIGENETIC PROCESS, MAYBE VIA THEORETICALLY POSSIBLE ENDOGENOUS ANTIDEPRESSANT-LIKE EFFECTS. IN CONTRAST, PATIENTS WITH HIGHER METHYLATION MIGHT POSSIBLY SUFFER FROM IMPAIRED EPIGENETIC ADAPTION TO CHRONIC STRESS. FURTHER, THE 5-HTTLPR/RS25531 ASSOCIATION WITH AMYGDALA ACTIVATION WAS CONFIRMED IN OUR LARGE SAMPLE. 2018 2 5267 35 PROMOTER ACTIVITY-BASED CASE-CONTROL ASSOCIATION STUDY ON SLC6A4 HIGHLIGHTING HYPERMETHYLATION AND ALTERED AMYGDALA VOLUME IN MALE PATIENTS WITH SCHIZOPHRENIA. ASSOCIATIONS BETWEEN ALTERED DNA METHYLATION OF THE SEROTONIN TRANSPORTER (5-HTT)-ENCODING GENE SLC6A4 AND EARLY LIFE ADVERSITY, MOOD AND ANXIETY DISORDERS, AND AMYGDALA REACTIVITY HAVE BEEN REPORTED. HOWEVER, FEW STUDIES HAVE EXAMINED EPIGENETIC ALTERATIONS OF SLC6A4 IN SCHIZOPHRENIA (SZ). WE EXAMINED CPG SITES OF SLC6A4, WHOSE DNA METHYLATION LEVELS HAVE BEEN REPORTED TO BE ALTERED IN BIPOLAR DISORDER, USING 3 INDEPENDENT COHORTS OF PATIENTS WITH SZ AND AGE-MATCHED CONTROLS. WE FOUND SIGNIFICANT HYPERMETHYLATION OF A CPG SITE IN SLC6A4 IN MALE PATIENTS WITH SZ IN ALL 3 COHORTS. WE SHOWED THAT CHRONIC ADMINISTRATION OF RISPERIDONE DID NOT AFFECT THE DNA METHYLATION STATUS AT THIS CPG SITE USING COMMON MARMOSETS, AND THAT IN VITRO DNA METHYLATION AT THIS CPG SITE DIMINISHED THE PROMOTER ACTIVITY OF SLC6A4. WE THEN GENOTYPED THE 5-HTT-LINKED POLYMORPHIC REGION (5-HTTLPR) AND INVESTIGATED THE RELATIONSHIP AMONG 5-HTTLPR, DNA METHYLATION, AND AMYGDALA VOLUME USING BRAIN IMAGING DATA. WE FOUND THAT PATIENTS HARBORING LOW-ACTIVITY 5-HTTLPR ALLELES SHOWED HYPERMETHYLATION AND THEY SHOWED A NEGATIVE CORRELATION BETWEEN DNA METHYLATION LEVELS AND LEFT AMYGDALA VOLUMES. THESE RESULTS SUGGEST THAT HYPERMETHYLATION OF THE CPG SITE IN SLC6A4 IS INVOLVED IN THE PATHOPHYSIOLOGY OF SZ, ESPECIALLY IN MALE PATIENTS HARBORING LOW-ACTIVITY 5-HTTLPR ALLELES. 2020 3 2035 47 EPIGENETIC CHANGES OF FKBP5 AS A LINK CONNECTING GENETIC AND ENVIRONMENTAL RISK FACTORS WITH STRUCTURAL AND FUNCTIONAL BRAIN CHANGES IN MAJOR DEPRESSION. THE GENE FOR THE GLUCOCORTICOID RECEPTOR REGULATOR FK506 BINDING PROTEIN 5 (FKBP5) PLAYS A ROLE FOR RISK, RESPONSE TO TREATMENT, AND CHANGES IN BRAIN AREAS IN MAJOR DEPRESSIVE DISORDER (MDD). CHRONIC STRESS IS ASSOCIATED WITH LOWER METHYLATION OF FKBP5. OUR AIM WAS TO INVESTIGATE WHETHER METHYLATION OF FKBP5 REFLECTED EXPOSURE TO CHILDHOOD ADVERSITY IN MDD AND CONTROLS AND WHETHER IT WAS ASSOCIATED WITH STRUCTURE AND FUNCTION OF EMOTIONAL PROCESSING REGIONS. FKBP5 INTRON 7 GR RESPONSE ELEMENT REGION METHYLATION AND RS1360780 ALLELIC STATUS WERE ASSESSED FROM WHOLE BLOOD IN 56 MDD ADULTS AND 50 CONTROLS. USING MAGNETIC RESONANCE IMAGING, WE ASSESSED GRAY MATTER CONCENTRATION OF SELECTED AREAS AND THEIR FUNCTION DURING VALENCE RECOGNITION OF EMOTIONAL IMAGES. CHILDHOOD ADVERSITY WAS INVESTIGATED USING THE CHILDHOOD TRAUMA QUESTIONNAIRE. IN MDD PATIENTS CARRYING THE HIGH-RISK T ALLELE OF RS1360780, LOWER METHYLATION OF FKBP5 WAS PREDICTED BY CHILDHOOD ADVERSITY (F=4.95, P=0.04). IN ALL PARTICIPANTS, LOWER FKBP5 INTRON METHYLATION LEVELS WERE ASSOCIATED WITH REDUCED GRAY MATTER CONCENTRATION IN THE INFERIOR FRONTAL ORBITAL GYRUS BILATERALLY (WALD CHI-SQUARE=11.93, P(FDR)<0.01) AND, IN MDD, WITH ITS BILATERALLY HIGHER ACTIVATION DURING VALENCE RECOGNITION (WALD CHI-SQUARE=5.58, P=0.02). ACTIVATION OF THIS REGION, REGARDLESS OF SIDE, WAS FOUND TO BE LOWER IN MDD COMPARED TO CONTROLS (WALD CHI-SQUARE=3.88, P=0.049) AND TO BE INVERSELY CORRELATED WITH DEPRESSION SEVERITY (WALD CHI-SQUARE=4.65, P=0.03). OUR FINDINGS SUPPORT THE HYPOTHESIS THAT, IN GENETICALLY PREDISPOSED INDIVIDUALS CARRYING A HIGH-RISK VARIANT OF THE GENE, CHILDHOOD MALTREATMENT MIGHT INDUCE DEMETHYLATION OF FKBP5. THIS IS IN TURN ASSOCIATED WITH STRUCTURAL AND FUNCTIONAL CHANGES IN THE INFERIOR FRONTAL ORBITAL GYRUS, A RELEVANT AREA FOR THE CLINICAL SYMPTOMS OF MDD. 2018 4 5637 35 SEROTONIN TRANSPORTER GENE POLYMORPHISMS IN SOUTHWESTERN IRANIAN PATIENTS WITH IRRITABLE BOWEL SYNDROME. BACKGROUND AND STUDY AIMS: IRRITABLE BOWEL SYNDROME IS A COMMON CHRONIC FUNCTIONAL GASTROINTESTINAL DISORDER OF UNKNOWN ETIOLOGY. SEROTONIN IS AN IMPORTANT FACTOR IN SENSORY SIGNALING IN THE BRAIN-GUT AXIS, WHICH PLAYS A KEY ROLE IN INTESTINAL MOTILITY AND SECRETION. SEROTONIN CLEARANCE IS MEDIATED BY A SPECIFIC PROTEIN CALLED THE SEROTONIN REUPTAKE TRANSPORTER. TRANSCRIPTION ACTIVITY OF THE SEROTONIN TRANSPORTER GENE IS AFFECTED BY SOME POLYMORPHISMS IN THIS GENE. THE AIM OF THIS STUDY WAS TO INVESTIGATE THE RELATIONSHIP BETWEEN SEROTONIN TRANSPORTER GENE POLYMORPHISMS AND IRRITABLE BOWEL SYNDROME. PATIENTS/MATERIAL AND METHODS: THE 5-HTTLPR, RS25531 AND STIN2VNTR POLYMORPHISMS OF THE SEROTONIN TRANSPORTER GENE WERE ANALYZED BY PCR-BASED METHODS IN 50 PATIENTS WITH IRRITABLE BOWEL SYNDROME AND 100 HEALTHY CONTROLS. RESULTS: SEROTONIN TRANSPORTER POLYMORPHISMS WERE SIMILAR IN PATIENTS AND HEALTHY CONTROLS. THERE WERE NO SIGNIFICANT DIFFERENCES IN ALLELE OR GENOTYPE FREQUENCIES BETWEEN THE TWO GROUPS. CONCLUSION: OUR FINDINGS SUGGEST THAT POLYMORPHISMS IN THE GENE ENCODING FOR THE SEROTONIN TRANSPORTER ARE NOT ASSOCIATED WITH IRRITABLE BOWEL SYNDROME. INTERACTIONS BETWEEN ENVIRONMENTAL FACTORS AND PREDISPOSING GENETIC FACTORS ARE IMPORTANT IN THE PATHOPHYSIOLOGY OF IRRITABLE BOWEL SYNDROME, AND FURTHER GENETIC AND EPIGENETIC RESEARCH MAY PROVIDE NOVEL INSIGHTS INTO THE MECHANISMS CONTRIBUTING TO THIS DISEASE. 2013 5 990 35 CHRONIC SOCIAL STRESS INDUCES DNA METHYLATION CHANGES AT AN EVOLUTIONARY CONSERVED INTERGENIC REGION IN CHROMOSOME X. CHRONIC STRESS RESULTING FROM PROLONGED EXPOSURE TO NEGATIVE LIFE EVENTS INCREASES THE RISK OF MOOD AND ANXIETY DISORDERS. ALTHOUGH CHRONIC STRESS CAN CHANGE GENE EXPRESSION RELEVANT FOR BEHAVIOR, MOLECULAR REGULATORS OF THIS CHANGE HAVE NOT BEEN FULLY DETERMINED. ONE PROCESS THAT COULD PLAY A ROLE IS DNA METHYLATION, AN EPIGENETIC PROCESS WHEREBY A METHYL GROUP IS ADDED ONTO NUCLEOTIDES, PREDOMINANTLY CYTOSINE IN THE CPG CONTEXT, AND WHICH CAN BE INDUCED BY CHRONIC STRESS. IT IS UNKNOWN TO WHAT EXTENT CHRONIC SOCIAL DEFEAT, A MODEL OF HUMAN SOCIAL STRESS, INFLUENCES DNA METHYLATION PATTERNS ACROSS THE GENOME. OUR STUDY ADDRESSED THIS QUESTION BY USING A TARGETED-CAPTURE APPROACH CALLED METHYL-SEQ TO INVESTIGATE DNA METHYLATION PATTERNS OF THE DENTATE GYRUS AT PUTATIVE REGULATORY REGIONS ACROSS THE MOUSE GENOME FROM MICE EXPOSED TO 14 DAYS OF SOCIAL DEFEAT. FINDINGS WERE REPLICATED IN INDEPENDENT COHORTS BY BISULFITE-PYROSEQUENCING. TWO DIFFERENTIALLY METHYLATED REGIONS (DMRS) WERE IDENTIFIED. ONE DMR WAS LOCATED AT INTRON 9 OF DROSHA, AND IT SHOWED REDUCED METHYLATION IN STRESSED MICE. THIS OBSERVATION REPLICATED IN ONE OF TWO INDEPENDENT COHORTS. A SECOND DMR WAS IDENTIFIED AT AN INTERGENIC REGION OF CHROMOSOME X, AND METHYLATION IN THIS REGION WAS INCREASED IN STRESSED MICE. THIS METHYLATION DIFFERENCE REPLICATED IN TWO INDEPENDENT COHORTS AND IN MAJOR DEPRESSIVE DISORDER (MDD) POSTMORTEM BRAINS. THESE RESULTS HIGHLIGHT A REGION NOT PREVIOUSLY KNOWN TO BE DIFFERENTIALLY METHYLATED BY CHRONIC SOCIAL DEFEAT STRESS AND WHICH MAY BE INVOLVED IN MDD. 2018 6 1418 36 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 7 577 35 BDNF PROMOTER METHYLATION AND GENETIC VARIATION IN LATE-LIFE DEPRESSION. THE REGULATION OF THE BRAIN-DERIVED NEUROTROPHIC FACTOR (BDNF) IS IMPORTANT FOR DEPRESSION PATHOPHYSIOLOGY AND EPIGENETIC REGULATION OF THE BDNF GENE MAY BE INVOLVED. THIS STUDY INVESTIGATED WHETHER BDNF METHYLATION IS A MARKER OF DEPRESSION. ONE THOUSAND AND TWENTY-FOUR PARTICIPANTS WERE RECRUITED AS PART OF A LONGITUDINAL STUDY OF PSYCHIATRIC DISORDERS IN GENERAL POPULATION ELDERLY (AGE ? 65). CLINICAL LEVELS OF DEPRESSION WERE ASSESSED USING THE MINI INTERNATIONAL NEUROPSYCHIATRIC INTERVIEW FOR THE DIAGNOSIS OF MAJOR DEPRESSIVE DISORDER ACCORDING TO THE DIAGNOSTIC AND STATISTICAL MANUAL OF MENTAL DISORDER IV CRITERIA, AND THE CENTRE FOR EPIDEMIOLOGIC STUDIES DEPRESSION SCALE (CES-D) FOR ASSESSMENT OF MODERATE TO SEVERE DEPRESSIVE SYMPTOMS. BUCCAL DNA METHYLATION AT THE TWO MOST WIDELY STUDIED BDNF PROMOTERS, I AND IV, WAS INVESTIGATED USING THE SEQUENOM MASSARRAY PLATFORM THAT ALLOWS HIGH-THROUGHPUT INVESTIGATION OF METHYLATION AT INDIVIDUAL CPG SITES WITHIN DEFINED GENOMIC REGIONS. IN MULTIVARIATE LINEAR REGRESSION ANALYSES ADJUSTED FOR A RANGE OF PARTICIPANT CHARACTERISTICS INCLUDING ANTIDEPRESSANT USE, DEPRESSION AT BASELINE, AS WELL AS CHRONIC LATE-LIFE DEPRESSION OVER THE 12-YEAR FOLLOW-UP, WERE ASSOCIATED WITH OVERALL HIGHER BDNF METHYLATION LEVELS, WITH TWO SITES SHOWING SIGNIFICANT ASSOCIATIONS (PROMOTER I, DELTA MEAN = 0.4%, P = 0.0002; PROMOTER IV, DELTA MEAN = 5.4%, P = 0.021). THREE SINGLE-NUCLEOTIDE POLYMORPHISMS (RS6265, RS7103411 AND RS908867) WERE ALSO FOUND TO MODIFY THE ASSOCIATION BETWEEN DEPRESSION AND PROMOTER I METHYLATION. AS ONE OF THE LARGEST EPIGENETIC STUDIES OF DEPRESSION, AND THE FIRST INVESTIGATING BDNF METHYLATION IN BUCCAL TISSUE, OUR FINDINGS HIGHLIGHT THE POTENTIAL FOR BUCCAL BDNF METHYLATION TO BE A BIOMARKER OF DEPRESSION. 2015 8 3080 33 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 9 344 35 ALTERED BDNF METHYLATION IN PATIENTS WITH CHRONIC MUSCULOSKELETAL PAIN AND HIGH BIOPSYCHOSOCIAL COMPLEXITY. PURPOSE: THE INTERMED INSTRUMENT, WHICH WAS DEVELOPED TO MEASURE PATIENT'S BIOPSYCHOSOCIAL (BPS) COMPLEXITY, REPRESENTS A POWERFUL DIAGNOSTIC AND THERAPEUTIC TOOL. EPIGENETIC CHANGES ARE THE INTERFACE BETWEEN SIGNALS FROM THE ENVIRONMENT AND GENETIC MODIFICATIONS, AFFECTING GENE EXPRESSION, IN PARTICULAR, BY DNA METHYLATION OF CPG DINUCLEOTIDES IN PROMOTOR REGIONS OF THE CORRESPONDING GENES. THE BRAIN-DERIVED NEUROTROPHIC FACTOR (BDNF) GENE PLAYS A CRUCIAL ROLE IN THE CENTRAL SENSITIZATION (CS) OF PAIN. IN THIS STUDY, WE HYPOTHESIZED THAT CHRONIC PAIN MODIFIES THE METHYLATION LEVELS OF THE BDNF GENE IN A MANNER THAT IS INTERCONNECTED WITH THE BPS STATUS. PATIENTS AND METHODS: FIFTY-EIGHT CHRONIC MUSCULOSKELETAL PAIN PATIENTS (CMSP) WERE ENROLLED IN THE STUDY. DNA WAS EXTRACTED FROM BLOOD SAMPLES, THE METHYLATION LEVELS OF 13 CPG SITES IN THE BDNF PROMOTER WERE MEASURED BY PYROSEQUENCING, AND ASSOCIATION STUDIES WITH VARIOUS PATIENT PARAMETERS AND THE INTERMED SCORES WERE PERFORMED. RESULTS: INTERESTINGLY, A NEGATIVE CORRELATION (-0.40) WAS FOUND BETWEEN THE TOTAL INTERMED SCORES AND THE AVERAGE CPG METHYLATION VALUES OF THE BDNF GENE, BUT NO CORRELATION WAS OBSERVED WITH THE SEVERITY OF PAIN, DEGREE OF ANXIETY, DEPRESSION, OR KINESIOPHOBIA AND CATASTROPHISM. MOREOVER, THE ASSOCIATION WAS INDEPENDENT OF AGE, SEX AND LEVEL OF COMORBIDITIES. CONCLUSION: THIS RESULT SHOWS THAT CMSP, IN ASSOCIATION WITH ITS BIOPSYCHOSOCIAL CONTEXT, EPIGENETICALLY DECREASES THE DEGREE OF METHYLATION OF THE BDNF PROMOTER AND SHOULD THEREFORE INCREASE THE LEVEL OF BDNF TRANSCRIPTION. IT ALSO SUGGESTS A ROLE OF THE INTERMED TOOL TO DETECT A RELATIONSHIP BETWEEN THE BPS COMPLEXITY AND THE EPIGENETIC CONTROL OF A TARGET GENE. THE POSSIBLE UPREGULATION OF BDNF EXPRESSION MIGHT BE, AT LEAST IN PART, THE SIGNAL FOR CHRONIC PAIN-INDUCED CENTRAL SENSITIZATION (CS). THIS COULD PARTLY EXPLAIN WHY PATIENTS WITH A HIGHER LEVEL OF COMPLEXITY FEEL MORE PAIN THAN THOSE WITH LOWER COMPLEXITY. 2020 10 575 38 BDNF METHYLATION AND MATERNAL BRAIN ACTIVITY IN A VIOLENCE-RELATED SAMPLE. IT IS KNOWN THAT INCREASED CIRCULATING GLUCOCORTICOIDS IN THE WAKE OF EXCESSIVE, CHRONIC, REPETITIVE STRESS INCREASES ANXIETY AND IMPAIRS BRAIN-DERIVED NEUROTROPHIC FACTOR (BDNF) SIGNALING. RECENT STUDIES OF BDNF GENE METHYLATION IN RELATION TO MATERNAL CARE HAVE LINKED HIGH BDNF METHYLATION LEVELS IN THE BLOOD OF ADULTS TO LOWER QUALITY OF RECEIVED MATERNAL CARE MEASURED VIA SELF-REPORT. YET THE SPECIFIC MECHANISMS BY WHICH THESE PHENOMENA OCCUR REMAIN TO BE ESTABLISHED. THE PRESENT STUDY EXAMINES THE LINK BETWEEN METHYLATION OF THE BDNF GENE PROMOTER REGION AND PATTERNS OF NEURAL ACTIVITY THAT ARE ASSOCIATED WITH MATERNAL RESPONSE TO STRESSFUL VERSUS NON-STRESSFUL CHILD STIMULI WITHIN A SAMPLE THAT INCLUDES MOTHERS WITH INTERPERSONAL VIOLENCE-RELATED PTSD (IPV-PTSD). 46 MOTHERS UNDERWENT FMRI. THE CONTRAST OF NEURAL ACTIVITY WHEN WATCHING CHILDREN-INCLUDING THEIR OWN-WAS THEN CORRELATED TO BDNF METHYLATION. CONSISTENT WITH THE EXISTING LITERATURE, THE PRESENT STUDY FOUND THAT MATERNAL BDNF METHYLATION WAS ASSOCIATED WITH HIGHER LEVELS OF MATERNAL ANXIETY AND GREATER CHILDHOOD EXPOSURE TO DOMESTIC VIOLENCE. FMRI RESULTS SHOWED A POSITIVE CORRELATION OF BDNF METHYLATION WITH MATERNAL BRAIN ACTIVITY IN THE ANTERIOR CINGULATE (ACC), AND VENTROMEDIAL PREFRONTAL CORTEX (VMPFC), REGIONS GENERALLY CREDITED WITH A REGULATORY FUNCTION TOWARD BRAIN AREAS THAT ARE GENERATING EMOTIONS. FURTHERMORE WE FOUND A NEGATIVE CORRELATION OF BDNF METHYLATION WITH THE ACTIVITY OF THE RIGHT HIPPOCAMPUS. SINCE OUR STIMULI FOCUS ON STRESSFUL PARENTING CONDITIONS, THESE DATA SUGGEST THAT THE CORRELATION BETWEEN VMPFC/ACC ACTIVITY AND BDNF METHYLATION MAY BE LINKED TO MOTHERS WHO ARE AT A DISADVANTAGE WITH RESPECT TO EMOTION REGULATION WHEN FACING STRESSFUL PARENTING SITUATIONS. OVERALL, THIS STUDY PROVIDES EVIDENCE THAT EPIGENETIC SIGNATURES OF STRESS-RELATED GENES CAN BE LINKED TO FUNCTIONAL BRAIN REGIONS REGULATING PARENTING STRESS, THUS ADVANCING OUR UNDERSTANDING OF MOTHERS AT RISK FOR STRESS-RELATED PSYCHOPATHOLOGY. 2015 11 2740 28 EXPOSURE TO EARLY LIFE STRESS RESULTS IN EPIGENETIC CHANGES IN NEUROTROPHIC FACTOR GENE EXPRESSION IN A PARKINSONIAN RAT MODEL. EARLY LIFE ADVERSITY INCREASES THE RISK OF MENTAL DISORDERS LATER IN LIFE. CHRONIC EARLY LIFE STRESS MAY ALTER NEUROTROPHIC FACTOR GENE EXPRESSION INCLUDING THOSE FOR BRAIN DERIVED NEUROTROPHIC FACTOR (BDNF) AND GLIAL CELL DERIVED NEUROTROPHIC FACTOR (GDNF) THAT ARE IMPORTANT IN NEURONAL GROWTH, SURVIVAL, AND MAINTENANCE. MATERNAL SEPARATION WAS USED IN THIS STUDY TO MODEL EARLY LIFE STRESS. FOLLOWING UNILATERAL INJECTION OF A MILD DOSE OF 6-HYDROXYDOPAMINE (6-OHDA), WE MEASURED CORTICOSTERONE (CORT) IN THE BLOOD AND STRIATUM OF STRESSED AND NONSTRESSED RATS; WE ALSO MEASURED DNA METHYLATION AND BDNF AND GDNF GENE EXPRESSION IN THE STRIATUM USING REAL TIME PCR. IN THE PRESENCE OF STRESS, WE FOUND THAT THERE WAS INCREASED CORTICOSTERONE CONCENTRATION IN BOTH BLOOD AND STRIATAL TISSUE. FURTHER TO THIS, WE FOUND HIGHER DNA METHYLATION AND DECREASED NEUROTROPHIC FACTOR GENE EXPRESSION. 6-OHDA LESION INCREASED NEUROTROPHIC FACTOR GENE EXPRESSION IN BOTH STRESSED AND NONSTRESSED RATS BUT THIS INCREASE WAS HIGHER IN THE NONSTRESSED RATS. OUR RESULTS SUGGEST THAT EXPOSURE TO EARLY POSTNATAL STRESS INCREASES CORTICOSTERONE CONCENTRATION WHICH LEADS TO INCREASED DNA METHYLATION. THIS EFFECT RESULTS IN DECREASED BDNF AND GDNF GENE EXPRESSION IN THE STRIATUM LEADING TO DECREASED PROTECTION AGAINST SUBSEQUENT INSULTS LATER IN LIFE. 2016 12 1537 28 DNA METHYLATION IN ADOLESCENTS WITH ANXIETY DISORDER: A LONGITUDINAL STUDY. ANXIETY DISORDERS (AD) TYPICALLY MANIFEST IN CHILDREN AND ADOLESCENTS AND MIGHT PERSIST INTO ADULTHOOD. HOWEVER, THERE ARE STILL FEW DATA CONCERNING EPIGENETIC MECHANISMS ASSOCIATED WITH ONSET, PERSISTENCE OR REMISSION OF AD OVER TIME. WE INVESTIGATED A COHORT OF ADOLESCENTS AND YOUNG ADULTS AT BASELINE (AGE; 13.19 +/- 2.38) AND AFTER 5 YEARS AND CLASSIFIED THEM ACCORDING TO THE AD DIAGNOSIS AND THEIR LONGITUDINAL TRAJECTORIES INTO 4 GROUPS: (1) TYPICALLY DEVELOPING COMPARISONS (TDC; CONTROL GROUP, N = 14); (2) INCIDENT (AD IN THE SECOND EVALUATION ONLY, N = 11); (3) PERSISTENT (AD IN BOTH EVALUATIONS, N = 14) AND (4) REMITTENT (AD IN THE FIRST EVALUATION ONLY, N = 8). DNA METHYLATION WAS EVALUATED WITH THE INFINIUM HUMANMETHYLATION450 BEADCHIP FROM SALIVA SAMPLES COLLECTED AT BOTH EVALUATIONS. GENE SET ENRICHMENT ANALYSIS WAS APPLIED TO CONSIDER BIOLOGICAL PATHWAYS. WE FOUND DECREASED DNA METHYLATION IN TDC GROUP WHILE THE CHRONIC CASES OF AD PRESENTED HYPERMETHYLATION IN CENTRAL NERVOUS SYSTEM DEVELOPMENT PATHWAYS. MOREOVER, WE SHOWED THAT THIS PERSISTENT GROUP ALSO PRESENTED HYPERMETHYLATION WHILE THE OTHER THREE GROUPS WERE ASSOCIATED WITH HYPOMETHYLATION IN NERVOUS SYSTEM DEVELOPMENT PATHWAY. INCIDENCE AND REMISSION GROUPS WERE ASSOCIATED WITH INCREASED AND DECREASED METHYLATION IN NEURON DEVELOPMENT PATHWAYS, RESPECTIVELY. LARGER STUDIES ARE LIKELY TO DETECT SPECIFIC GENES RELEVANT TO AD. 2018 13 1967 42 EPIGENETIC ALTERATION OF THE DOPAMINE TRANSPORTER GENE IN ALCOHOL-DEPENDENT PATIENTS IS ASSOCIATED WITH AGE. CHRONIC ALCOHOL ABUSE AND DEPENDENCE ARE ASSOCIATED WITH DYSFUNCTIONAL DOPAMINERGIC NEUROTRANSMISSION IN MESOCORTICOLIMBIC CIRCUITS. GENETIC AND ENVIRONMENTAL FACTORS HAVE BEEN SHOWN TO MODULATE SUSCEPTIBILITY TO ALCOHOL DEPENDENCE, AND BOTH MAY ACT THROUGH EPIGENETIC MECHANISMS THAT CAN MODULATE GENE EXPRESSION, E.G. DNA METHYLATION AT CPG SITES. RECENT STUDIES HAVE SUGGESTED THAT DNA METHYLATION PATTERNS MAY CHANGE OVER TIME. HOWEVER, FEW DATA ARE AVAILABLE CONCERNING THE RATE OF THESE CHANGES IN SPECIFIC GENES. A RECENT STUDY FOUND THAT HYPERMETHYLATION OF THE PROMOTER OF THE DOPAMINE TRANSPORTER (DAT) GENE WAS POSITIVELY CORRELATED WITH ALCOHOL DEPENDENCE AND NEGATIVELY CORRELATED WITH ALCOHOL CRAVING. THE AIM OF THE PRESENT STUDY WAS TO REPLICATE THESE FINDINGS IN A LARGER SAMPLE OF ALCOHOL-DEPENDENT PATIENTS AND POPULATION-BASED CONTROLS MATCHED FOR AGE AND SEX. NO DIFFERENCE IN METHYLATION LEVEL WAS OBSERVED BETWEEN PATIENTS AND CONTROLS, AND NO DIFFERENCE IN METHYLATION LEVEL WAS OBSERVED BEFORE AND AFTER ALCOHOL WITHDRAWAL IN PATIENTS. HOWEVER, PATIENTS WITH MORE SEVERE CRAVING SHOWED A TREND TOWARDS LOWER DAT METHYLATION LEVELS (P = 0.07), WHICH IS CONSISTENT WITH PREVIOUS FINDINGS. FURTHERMORE, IN OUR OVERALL SAMPLE, DAT METHYLATION LEVELS INCREASED WITH AGE. INTERESTINGLY, A SEPARATE ANALYSIS OF PATIENTS SUGGESTED THAT THIS FINDING WAS MAINLY DRIVEN BY THE PATIENT GROUP. ALTHOUGH THE PRESENT DATA DO NOT CLARIFY WHETHER CHRONIC ALCOHOL ABUSE IS RESPONSIBLE FOR THIS PHENOMENON OR MERELY ENHANCES AN AGEING-SPECIFIC PROCESS, OUR FINDINGS SUGGEST THAT HYPERMETHYLATION IN ALCOHOL-DEPENDENT PATIENTS IS A CONSEQUENCE, RATHER THAN A CAUSE, OF THE DISORDER. 2014 14 5273 36 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 1820 32 EFFECTS OF CHRONIC RESTRAINT STRESS ON THE GLOBAL DNA METHYLATION PROFILE OF RAT LUNG CELLS: MODULATION BY PHYSICAL EXERCISE. THE POTENTIAL OF BEHAVIORAL STRESS TO AFFECT EPIGENETIC MECHANISMS OF NON-ENCEPHALIC TISSUES IS STILL UNDERESTIMATED. IN THE PRESENT STUDY WE EVALUATED THE EFFECTS OF CHRONIC BEHAVIORAL STRESS ON THE DNA METHYLATION PROFILE OF RAT LUNG CELLS. FURTHERMORE, WE EVALUATED THE POTENTIAL OF PHYSICAL EXERCISE TO MODULATE THE CHANGES EVOKED BY BEHAVIORAL STRESS IN LUNG CELLS. MALE WISTAR RATS WERE DIVIDED INTO FOUR EXPERIMENTAL GROUPS: (1) ANIMALS SUBMITTED TO CHRONIC RESTRAINT STRESS (CRS) (ST GROUP) DURING THE PERIOD OF THE 67TH-80TH POSTNATAL DAY (PND); (2) ANIMALS SUBMITTED TO PHYSICAL EXERCISE (EX GROUP) DURING THE 53RD-79TH PND; (3) ANIMALS SUBMITTED TO SWIMMING DURING THE 53RD-79TH PND AND TO CRS DURING THE 67TH-80TH PND (EX-ST GROUP); AND (4) ANIMALS NOT SUBMITTED TO STRESS OR SWIMMING PROTOCOLS (CTL). GLOBAL DNA METHYLATION WAS QUANTIFIED USING AN ELISA-BASED APPROACH AND GENE EXPRESSION WAS EVALUATED BY REAL TIME PCR. A DECREASED GLOBAL DNA METHYLATION PROFILE WAS OBSERVED IN THE ST GROUP, HOWEVER PHYSICAL EXERCISE DEMONSTRATED PROTECTION OF LUNG CELLS FROM THIS STRESS-RELATED HYPOMETHYLATION. INCREASED EXPRESSION OF THE DNMT1 GENE WAS EVIDENCED IN THE ST GROUP, WHEREAS PHYSICAL EXERCISE WAS SHOWN TO PROTECT LUNG CELLS FROM THIS STRESS-RELATED EFFECT IN THE EX-ST GROUP. COMPARATIVE ANALYSIS OF THE ST AND EX GROUPS REVEALED OPPOSITE EFFECTS ON THE EXPRESSION OF DNMT3A AND DNMT3B; HOWEVER, A STRESS-RELATED INCREASE IN EXPRESSION OF DNMT3A AND DNMT3B WAS NOT SEEN IN THE EX-ST GROUP. OUR DATA SHOWED THAT BEHAVIORAL STRESS INDUCED SIGNIFICANT CHANGES IN THE DNA METHYLATION PROFILE OF RAT LUNG CELLS AND THAT THIS COULD BE MODULATED BY PHYSICAL EXERCISE. 2017 16 5467 35 RESILIENT PHENOTYPE IN CHRONIC MILD STRESS PARADIGM IS ASSOCIATED WITH ALTERED EXPRESSION LEVELS OF MIR-18A-5P AND SEROTONIN 5-HT(1A) RECEPTOR IN DORSAL PART OF THE HIPPOCAMPUS. DISTURBED SEROTONERGIC SIGNALING IN THE HIPPOCAMPUS OBSERVED IN MANY INDIVIDUALS VULNERABLE TO STRESS HAS BEEN SUGGESTED AS ONE OF THE PRIMARY FACTORS CONTRIBUTING TO THE DEVELOPMENT OF DEPRESSION. HOWEVER, LITTLE IS KNOWN ABOUT THE PHYSIOLOGY OF THE BRAIN IN THE RESILIENT PHENOTYPE. RESILIENT SUBJECTS MAINTAIN A POSITIVE MOOD AND PSYCHOLOGICAL BALANCE DESPITE BEING UNDER THE STRESS INFLUENCE. IN OUR STUDY, WE GENERATED STRESS-VULNERABLE AND RESILIENT RATS BY USING A CHRONIC MILD STRESS (CMS) PARADIGM. USING DIFFERENT MOLECULAR APPROACHES, WE REVEALED THAT RESILIENT ANIMALS EXHIBITED A SIGNIFICANTLY DECREASED EXPRESSION LEVEL OF MIR-18A-5P AND, IN THE SAME TIME, AN ELEVATED LEVEL OF 5-HT1AR IN DORSAL, BUT NOT VENTRAL, PART OF THE HIPPOCAMPUS. DESCRIBED BIOCHEMICAL CHANGES WERE NOT OBSERVED IN ANIMALS BEHAVIORALLY VULNERABLE TO STRESS. FURTHER, IN VITRO ANALYSIS SHOWED THAT MIR-18A-5P MAY BE A NEGATIVE EPIGENETIC REGULATOR OF 5-HT1AR SINCE THE TREATMENT OF ADULT HIPPOCAMPAL NEURONS WITH MIR-18A-5P MIMIC SIGNIFICANTLY LOWERED THE EXPRESSION LEVEL OF MRNA ENCODING 5-HT1AR. MOREOVER, BIOINFORMATIC ANALYSIS OF POTENTIAL TARGET GENES EXPRESSED IN THE HIPPOCAMPUS AND BEING REGULATED BY MIR-18A-5P SHOWED THAT THIS MICRORNA MAY REGULATE BIOLOGICAL PROCESSES, SUCH AS AXONOGENESIS, WHICH ARE IMPORTANT IN THE FUNCTIONING OF THE HIPPOCAMPUS IN BOTH RATS AND HUMANS. ALL THESE MOLECULAR FEATURES MAY CONTRIBUTE TO SEROTONERGIC HOMEOSTATIC BALANCE AT THE LEVEL OF SEROTONIN TURNOVER OBSERVED IN HIPPOCAMPI OF RESILIENT BUT NOT STRESS-VULNERABLE RATS. DELINEATION OF FURTHER MOLECULAR AND BIOCHEMICAL MARKERS UNDERLYING RESILIENCE TO STRESS MAY CONTRIBUTE TO THE DEVELOPMENT OF NEW ANTIDEPRESSANT STRATEGIES WHICH WILL RESTORE RESILIENT PHENOTYPE IN DEPRESSED PATIENTS. 2019 17 1808 34 EFFECTS OF ADOLESCENT SOCIAL STRESS AND ANTIDEPRESSANT TREATMENT ON COGNITIVE INFLEXIBILITY AND BDNF EPIGENETIC MODIFICATIONS IN THE MPFC OF ADULT MICE. ADOLESCENT SOCIAL STRESS (ASS) CAN INCREASE SUSCEPTIBILITY TO DEPRESSION IN ADULTHOOD. HOWEVER, THE UNDERLYING PSYCHOLOGICAL AND NEURAL MECHANISMS REMAIN UNCLEAR. CORTICALLY MEDIATED COGNITIVE DYSFUNCTIONS ARE INCREASINGLY RECOGNIZED AS AN INDEPENDENT AND IMPORTANT RISK FACTOR OF DEPRESSION. USING SOCIAL DEFEAT STRESS, A CLASSICAL ANIMAL MODEL OF DEPRESSION, OUR PREVIOUS STUDIES FOUND THAT MICE SUBJECTED TO THIS FORM OF STRESS DURING EARLY ADOLESCENCE DISPLAYED COGNITIVE INFLEXIBILITY (CI) IN ADULTHOOD. THIS CHANGE WAS ACCOMPANIED BY A DOWN-REGULATION OF BDNF GENE EXPRESSION IN THE MEDIAL PREFRONTAL CORTEX (MPFC); THIS GENE ENCODES A KEY MOLECULE INVOLVED IN DEPRESSION AND ANTIDEPRESSANT ACTION. IN THE PRESENT PAPER, WE IDENTIFIED EPIGENETIC MODIFICATION OF BDNF AS A POSSIBLE MECHANISM UNDERLYING THE BEHAVIORAL AND MOLECULAR CHANGES. ASS INDUCED A SET OF DEPRESSIVE PHENOTYPES, INCLUDING INCREASED SOCIAL AVOIDANCE AND CI, AS WELL AS REDUCED LEVELS OF TOTAL BDNF AND ISOFORM IV BUT NOT ISOFORM I OR VI TRANSCRIPTS IN THE MPFC. IN PARALLEL WITH CHANGES IN BDNF GENE EXPRESSION, PREVIOUSLY STRESSED ADULT MICE SHOWED INCREASED LEVELS OF DIMETHYLATION OF HISTONE H3 AT LYSINE K9 (H3K9ME2) IMMEDIATELY DOWNSTREAM OF THE BDNF IV PROMOTER. ON THE OTHER HAND, NO DIFFERENCES WERE FOUND IN TRIMETHYLATION OF HISTONE H3 AT LYSINE K4 (H3K4ME3) OR IN ACETYLATION OF HISTONE H3 AT LYSINE K9 (H3K9AC) OR AT K4 (H3K4AC) IN THE BDNF IV PROMOTER. LIKEWISE, NO ALTERATIONS WERE FOUND IN DNA METHYLATION OF THE BDNF IV PROMOTER. ADDITIONALLY, TREATMENT WITH THE CHRONIC ANTIDEPRESSANT TRANYLCYPROMINE REVERSED BDNF EPIGENETIC CHANGES AND RELATED GENE TRANSCRIPTION WHILE ALSO REVERSING CI, BUT NOT SOCIAL AVOIDANCE, IN PREVIOUSLY STRESSED ADULT MICE. THESE RESULTS SUGGEST THAT EPIGENETIC CHANGES TO THE BDNF GENE IN THE MPFC AFTER ADOLESCENT SOCIAL ADVERSITY MAY BE INVOLVED IN THE REGULATION OF COGNITIVE DYSFUNCTION IN DEPRESSION AND ANTIDEPRESSANT ACTION IN ADULTHOOD. 2018 18 3914 36 LIFETIME STRESS ACCELERATES EPIGENETIC AGING IN AN URBAN, AFRICAN AMERICAN COHORT: RELEVANCE OF GLUCOCORTICOID SIGNALING. BACKGROUND: CHRONIC PSYCHOLOGICAL STRESS IS ASSOCIATED WITH ACCELERATED AGING AND INCREASED RISK FOR AGING-RELATED DISEASES, BUT THE UNDERLYING MOLECULAR MECHANISMS ARE UNCLEAR. RESULTS: WE EXAMINED THE EFFECT OF LIFETIME STRESSORS ON A DNA METHYLATION-BASED AGE PREDICTOR, EPIGENETIC CLOCK. AFTER CONTROLLING FOR BLOOD CELL-TYPE COMPOSITION AND LIFESTYLE PARAMETERS, CUMULATIVE LIFETIME STRESS, BUT NOT CHILDHOOD MALTREATMENT OR CURRENT STRESS ALONE, PREDICTED ACCELERATED EPIGENETIC AGING IN AN URBAN, AFRICAN AMERICAN COHORT (N = 392). THIS EFFECT WAS PRIMARILY DRIVEN BY PERSONAL LIFE STRESSORS, WAS MORE PRONOUNCED WITH ADVANCING AGE, AND WAS BLUNTED IN INDIVIDUALS WITH HIGHER CHILDHOOD ABUSE EXPOSURE. HYPOTHESIZING THAT THESE EPIGENETIC EFFECTS COULD BE MEDIATED BY GLUCOCORTICOID SIGNALING, WE FOUND THAT A HIGH NUMBER (N = 85) OF EPIGENETIC CLOCK CPG SITES WERE LOCATED WITHIN GLUCOCORTICOID RESPONSE ELEMENTS. WE FURTHER EXAMINED THE FUNCTIONAL EFFECTS OF GLUCOCORTICOIDS ON EPIGENETIC CLOCK CPGS IN AN INDEPENDENT SAMPLE WITH GENOME-WIDE DNA METHYLATION (N = 124) AND GENE EXPRESSION DATA (N = 297) BEFORE AND AFTER EXPOSURE TO THE GLUCOCORTICOID RECEPTOR AGONIST DEXAMETHASONE. DEXAMETHASONE INDUCED DYNAMIC CHANGES IN METHYLATION IN 31.2 % (110/353) OF THESE CPGS AND TRANSCRIPTION IN 81.7 % (139/170) OF GENES NEIGHBORING EPIGENETIC CLOCK CPGS. DISEASE ENRICHMENT ANALYSIS OF THESE DEXAMETHASONE-REGULATED GENES SHOWED ENRICHED ASSOCIATION FOR AGING-RELATED DISEASES, INCLUDING CORONARY ARTERY DISEASE, ARTERIOSCLEROSIS, AND LEUKEMIAS. CONCLUSIONS: CUMULATIVE LIFETIME STRESS MAY ACCELERATE EPIGENETIC AGING, AN EFFECT THAT COULD BE DRIVEN BY GLUCOCORTICOID-INDUCED EPIGENETIC CHANGES. THESE FINDINGS CONTRIBUTE TO OUR UNDERSTANDING OF MECHANISMS LINKING CHRONIC STRESS WITH ACCELERATED AGING AND HEIGHTENED DISEASE RISK. 2015 19 1789 25 EFFECT OF CHRONIC HEROIN AND COCAINE ADMINISTRATION ON GLOBAL DNA METHYLATION IN BRAIN AND LIVER. DRUG ABUSE IS ASSOCIATED WITH EPIGENETIC CHANGES, SUCH AS HISTONE MODIFICATIONS AND DNA METHYLATION. THE PURPOSE OF THE PRESENT STUDY WAS TO EXAMINE THE EFFECT OF CHRONIC COCAINE AND HEROIN ADMINISTRATION ON GLOBAL DNA METHYLATION IN BRAIN AND LIVER. MALE, 8 WEEK OLD, C57BL/6J MICE RECEIVED HEROIN IN A CHRONIC 'INTERMITTENT' ESCALATING DOSE PARADIGM, OR COCAINE IN A CHRONIC ESCALATING DOSE 'BINGE' PARADIGM, WHICH MIMIC THE HUMAN PATTERN OF OPIOID OR COCAINE ABUSE RESPECTIVELY. FOLLOWING SACRIFICE, LIVERS AND BRAINS WERE REMOVED AND DNA WAS EXTRACTED FROM THEM. THE EXTRACTED DNA WAS HYDROLYZED AND 2'-DEOXYCYTIDINE AND 5-METHYL-2'-DEOXYCYTIDINE WERE DETERMINED BY HPLC-UV. THE % 5-METHYL-2'-DEOXYCYTIDINE CONTENT OF DNA WAS SIGNIFICANTLY HIGHER IN THE BRAIN COMPARED TO THE LIVER. THERE WERE NO DIFFERENCES BETWEEN THE CONTROL ANIMALS AND THE COCAINE OR HEROIN TREATED ANIMALS IN NEITHER OF THE TISSUES EXAMINED, WHICH IS SURPRISING SINCE COCAINE ADMINISTRATION INDUCED GROSS MORPHOLOGICAL CHANGES IN THE LIVER. MOREOVER, THERE WAS NO DIFFERENCE IN THE % 5-METHYL-2'-DEOXYCYTIDINE CONTENT OF DNA BETWEEN THE COCAINE AND THE HEROIN TREATED ANIMALS. THE GLOBAL DNA METHYLATION STATUS IN THE BRAIN AND LIVER OF MICE CHRONICALLY TREATED WITH COCAINE OR HEROIN REMAINS UNAFFECTED, BUT THIS FINDING CANNOT EXCLUDE THE EXISTENCE OF ANATOMICAL REGION OR GENE-SPECIFIC METHYLATION DIFFERENCES. THIS IS THE FIRST TIME THAT GLOBAL DNA METHYLATION IN THE LIVER AND WHOLE BRAIN HAS BEEN STUDIED FOLLOWING CHRONIC COCAINE OR HEROIN TREATMENT. 2013 20 524 33 ASSOCIATIONS OF BDNF GENOTYPE AND PROMOTER METHYLATION WITH ACUTE AND LONG-TERM STROKE OUTCOMES IN AN EAST ASIAN COHORT. BACKGROUND: BRAIN DERIVED NEUROTROPHIC FACTOR (BDNF) HAS BEEN SHOWN TO PLAY AN IMPORTANT ROLE IN POSTSTROKE RECOVERY. BDNF SECRETION IS INFLUENCED BY GENETIC AND EPIGENETIC PROFILES. THIS STUDY AIMED TO INVESTIGATE WHETHER BDNF VAL66MET POLYMORPHISM AND PROMOTER METHYLATION STATUS WERE ASSOCIATED WITH OUTCOMES AT TWO WEEKS AND ONE YEAR AFTER STROKE. METHODS AND FINDINGS: A TOTAL OF 286 PATIENTS WERE EVALUATED AT THE TIME OF ADMISSION AND TWO WEEKS AFTER STROKE, AND 222 (78%) WERE FOLLOWED ONE YEAR LATER IN ORDER TO EVALUATE CONSEQUENCES OF STROKE AT BOTH ACUTE AND CHRONIC STAGES. STROKE OUTCOMES WERE DICHOTOMISED INTO GOOD AND POOR BY THE MODIFIED RANKIN SCALE. STROKE SEVERITY (NATIONAL INSTITUTES OF HEALTH STROKE SCALE), PHYSICAL DISABILITY (BARTHEL INDEX), AND COGNITIVE FUNCTION (MINI-MENTAL STATE EXAMINATION) WERE MEASURED. ASSOCIATIONS OF BDNF GENOTYPE AND METHYLATION STATUS ON STROKE OUTCOMES AND ASSESSMENT SCALE SCORES WERE INVESTIGATED USING LOGISTIC REGRESSION, REPEATED MEASURES ANOVA AND PARTIAL CORRELATION TESTS. BDNF VAL66MET POLYMORPHISM WAS INDEPENDENTLY ASSOCIATED WITH POOR OUTCOME AT 2 WEEKS AND AT 1 YEAR, AND WITH WORSENING PHYSICAL DISABILITY AND COGNITIVE FUNCTION OVER THAT PERIOD. HIGHER BDNF PROMOTER METHYLATION STATUS WAS INDEPENDENTLY ASSOCIATED WITH WORSE OUTCOMES AT 1 YEAR, AND WITH THE WORSENING OF PHYSICAL DISABILITY AND COGNITIVE FUNCTION. NO SIGNIFICANT GENOTYPE-METHYLATION INTERACTIONS WERE FOUND. CONCLUSIONS: A ROLE FOR BDNF IN POSTSTROKE RECOVERY WAS SUPPORTED, AND CLINICAL UTILITY OF BDNF GENETIC AND EPIGENETIC PROFILE AS PROGNOSTIC BIOMARKERS AND A TARGET FOR DRUG DEVELOPMENT WAS SUGGESTED. 2012