1 660 142 BLOOD LEVELS OF T-CELL RECEPTOR EXCISION CIRCLES (TRECS) PROVIDE AN INDEX OF EXPOSURE TO TRAUMATIC STRESS IN MICE AND HUMANS. EXPOSURE TO STRESS TRIGGERS BIOLOGICAL CHANGES THROUGHOUT THE BODY. ACCUMULATING EVIDENCE INDICATES THAT ALTERATIONS IN IMMUNE SYSTEM FUNCTION ARE ASSOCIATED WITH THE DEVELOPMENT OF STRESS-ASSOCIATED ILLNESSES SUCH AS MAJOR DEPRESSIVE DISORDER AND POST-TRAUMATIC STRESS DISORDER, INCREASING INTEREST IN IDENTIFYING IMMUNE MARKERS THAT PROVIDE INSIGHT INTO MENTAL HEALTH. RECOMBINATION EVENTS DURING T-CELL RECEPTOR REARRANGEMENT AND T-CELL MATURATION IN THE THYMUS PRODUCE CIRCULAR DNA FRAGMENTS CALLED T-CELL RECEPTOR EXCISION CIRCLES (TRECS) THAT CAN BE UTILIZED AS INDICATORS OF THYMIC FUNCTION AND NUMBERS OF NEWLY EMIGRATING T-CELLS. GIVEN DATA SUGGESTING THAT STRESS AFFECTS THYMUS FUNCTION, WE EXAMINED WHETHER BLOOD LEVELS OF TRECS MIGHT SERVE AS A QUANTITATIVE PERIPHERAL INDEX OF CUMULATIVE STRESS EXPOSURE AND ITS PHYSIOLOGICAL CORRELATES. WE HYPOTHESIZED THAT CHRONIC STRESS EXPOSURE WOULD COMPROMISE THYMUS FUNCTION AND PRODUCE CORRESPONDING DECREASES IN LEVELS OF TRECS. IN MALE MICE, EXPOSURE TO CHRONIC SOCIAL DEFEAT STRESS (CSDS) PRODUCED THYMIC INVOLUTION, ADRENAL HYPERTROPHY, AND DECREASED LEVELS OF TRECS IN BLOOD. EXTENDING THESE STUDIES TO HUMANS REVEALED ROBUST INVERSE CORRELATIONS BETWEEN LEVELS OF CIRCULATING TRECS AND CHILDHOOD EMOTIONAL AND PHYSICAL ABUSE. CELL-TYPE SPECIFIC ANALYSES ALSO REVEALED ASSOCIATIONS BETWEEN TREC LEVELS AND BLOOD CELL COMPOSITION, AS WELL AS CELL-TYPE SPECIFIC METHYLATION CHANGES IN CD4T + AND CD8T + CELLS. ADDITIONALLY, TREC LEVELS CORRELATED WITH EPIGENETIC AGE ACCELERATION, A COMMON BIOMARKER OF STRESS EXPOSURE. OUR FINDINGS DEMONSTRATE ALIGNMENT BETWEEN FINDINGS IN MICE AND HUMANS AND SUGGEST THAT BLOOD-BORNE TRECS ARE A TRANSLATIONALLY-RELEVANT BIOMARKER THAT CORRELATES WITH, AND PROVIDES INSIGHT INTO, THE CUMULATIVE PHYSIOLOGICAL AND IMMUNE-RELATED IMPACTS OF STRESS EXPOSURE IN MAMMALS. 2022 2 1162 28 CONTRASTING EFFECTS OF ACUTE AND CHRONIC STRESS ON THE TRANSCRIPTOME, EPIGENOME, AND IMMUNE RESPONSE OF ATLANTIC SALMON. STRESS EXPERIENCED DURING EARLY LIFE MAY HAVE LASTING EFFECTS ON THE IMMUNE SYSTEM, WITH IMPACTS ON HEALTH AND DISEASE DEPENDENT ON THE NATURE AND DURATION OF THE STRESSOR. THE EPIGENOME IS ESPECIALLY SENSITIVE TO ENVIRONMENTAL STIMULI DURING EARLY LIFE AND REPRESENTS A POTENTIAL MECHANISM THROUGH WHICH STRESS MAY CAUSE LONG-LASTING HEALTH EFFECTS. HOWEVER, THE EXTENT TO WHICH THE EPIGENOME RESPONDS DIFFERENTLY TO CHRONIC VS ACUTE STRESSORS IS UNCLEAR, ESPECIALLY FOR NON-MAMMALIAN SPECIES. WE EXAMINED THE EFFECTS OF ACUTE STRESS (COLD-SHOCK DURING EMBRYOGENESIS) AND CHRONIC STRESS (ABSENCE OF TANK ENRICHMENT DURING LARVAL-STAGE) ON GLOBAL GENE EXPRESSION (USING RNA-SEQ) AND DNA METHYLATION (USING RRBS) IN THE GILLS OF ATLANTIC SALMON (SALMO SALAR) FOUR MONTHS AFTER HATCHING. CHRONIC STRESS INDUCED PRONOUNCED TRANSCRIPTIONAL DIFFERENCES, WHILE ACUTE STRESS CAUSED FEW LASTING TRANSCRIPTIONAL EFFECTS. HOWEVER, BOTH ACUTE AND CHRONIC STRESS CAUSED LASTING AND CONTRASTING CHANGES IN THE METHYLOME. CRUCIALLY, WE FOUND THAT ACUTE STRESS ENHANCED TRANSCRIPTIONAL IMMUNE RESPONSE TO A PATHOGENIC CHALLENGE (BACTERIAL LIPOPOLYSACCHARIDE, LPS), WHILE CHRONIC STRESS SUPPRESSED IT. WE IDENTIFIED STRESS-INDUCED CHANGES IN PROMOTER AND GENE-BODY METHYLATION THAT WERE ASSOCIATED WITH ALTERED EXPRESSION FOR A SMALL PROPORTION OF IMMUNE-RELATED GENES, AND EVIDENCE OF WIDER EPIGENETIC REGULATION WITHIN SIGNALLING PATHWAYS INVOLVED IN IMMUNE RESPONSE. OUR RESULTS SUGGEST THAT STRESS CAN AFFECT IMMUNO-COMPETENCE THROUGH EPIGENETIC MECHANISMS, AND HIGHLIGHT THE MARKEDLY DIFFERENT EFFECTS OF CHRONIC LARVAL AND ACUTE EMBRYONIC STRESS. THIS KNOWLEDGE COULD BE USED TO HARNESS THE STIMULATORY EFFECTS OF ACUTE STRESS ON IMMUNITY, PAVING THE WAY FOR IMPROVED STRESS AND DISEASE MANAGEMENT THROUGH EPIGENETIC CONDITIONING. 2018 3 4736 30 NOVEL EPIGENETIC BIOMARKERS MEDIATING BISPHENOL A EXPOSURE AND METABOLIC PHENOTYPES IN FEMALE MICE. THERE IS COMPELLING EVIDENCE THAT EPIGENETIC MODIFICATIONS LINK DEVELOPMENTAL ENVIRONMENTAL INSULTS TO ADULT DISEASE SUSCEPTIBILITY. ANIMAL STUDIES HAVE ASSOCIATED PERINATAL BISPHENOL A (BPA) EXPOSURE TO ALTERED DNA METHYLATION, BUT THESE STUDIES ARE OFTEN LIMITED TO CANDIDATE GENE AND GLOBAL NON-LOCI-SPECIFIC APPROACHES. BY USING AN EPIGENOME-WIDE DISCOVERY PLATFORM, WE ELUCIDATED EPIGENETIC ALTERATIONS IN LIVER TISSUE FROM ADULT MICE OFFSPRING (10 MONTHS) FOLLOWING PERINATAL BPA EXPOSURE AT HUMAN PHYSIOLOGICALLY RELEVANT DOSES (50-NG, 50-MUG, AND 50-MG BPA/KG DIET). BIOLOGICAL PATHWAY ANALYSIS IDENTIFIED AN ENRICHMENT OF SIGNIFICANT DIFFERENTIALLY METHYLATED REGIONS IN METABOLIC PATHWAYS AMONG FEMALES. FURTHERMORE, THROUGH THE USE OF TOP ENRICHED BIOLOGICAL PATHWAYS, 4 CANDIDATE GENES WERE CHOSEN TO ASSESS DNA METHYLATION AS A MEDIATING FACTOR LINKING THE ASSOCIATION OF PERINATAL BPA EXPOSURE TO METABOLIC PHENOTYPES PREVIOUSLY OBSERVED IN FEMALE OFFSPRING. DNA METHYLATION STATUS AT JANUS KINASE-2 (JAK-2), RETINOID X RECEPTOR (RXR), REGULATORY FACTOR X-ASSOCIATED PROTEIN (RFXAP), AND TRANSMEMBRANE PROTEIN 238 (TMEM238) WAS USED WITHIN A MEDIATIONAL REGRESSION ANALYSIS. DNA METHYLATION IN ALL FOUR OF THE CANDIDATE GENES WAS IDENTIFIED AS A MEDIATOR IN THE MECHANISTIC PATHWAY OF DEVELOPMENTAL BPA EXPOSURE AND FEMALE-SPECIFIC ENERGY EXPENDITURE, BODY WEIGHT, AND BODY FAT PHENOTYPES. DATA GENERATED FROM THIS STUDY ARE CRUCIAL FOR DECIPHERING THE MECHANISTIC ROLE OF EPIGENETICS IN THE PATHOGENESIS OF CHRONIC DISEASE AND THE DEVELOPMENT OF EPIGENETIC-BASED PREVENTION AND THERAPEUTIC STRATEGIES FOR COMPLEX HUMAN DISEASE. 2017 4 2776 38 EXTRAUTERINE GROWTH RESTRICTION ON PULMONARY VASCULAR ENDOTHELIAL DYSFUNCTION IN ADULT MALE RATS: THE ROLE OF EPIGENETIC MECHANISMS. OBJECTIVE: EARLY POSTNATAL LIFE IS CONSIDERED AS A CRITICAL TIME WINDOW FOR THE DETERMINATION OF LONG-TERM METABOLIC STATES AND ORGAN FUNCTIONS. EXTRAUTERINE GROWTH RESTRICTION (EUGR) CAUSES THE DEVELOPMENT OF ADULT-ONSET CHRONIC DISEASES, INCLUDING PULMONARY HYPERTENSION. HOWEVER, THE EFFECTS OF NUTRITIONAL DISADVANTAGES DURING THE EARLY POSTNATAL PERIOD ON PULMONARY VASCULAR CONSEQUENCES IN LATER LIFE ARE NOT FULLY UNDERSTOOD. OUR STUDY WAS DESIGNED TO TEST WHETHER EPIGENETICS DYSREGULATION MEDIATES THE CELLULAR MEMORY OF THIS EARLY POSTNATAL EVENT. METHODS AND RESULTS: TO TEST THIS HYPOTHESIS, WE ISOLATED PULMONARY VASCULAR ENDOTHELIAL CELLS BY MAGNETIC-ACTIVATED CELL SORTING FROM EUGR AND CONTROL RATS. A POSTNATAL INSULT, NUTRITIONAL RESTRICTION-INDUCED EUGR CAUSED DEVELOPMENT OF AN INCREASED PULMONARY ARTERY PRESSURE AT 9 WEEKS OF AGE IN MALE SPRAGUE-DAWLEY RATS. METHYL-DNA IMMUNE PRECIPITATION CHIP, GENOME-SCALE MAPPING STUDIES TO SEARCH FOR DIFFERENTIALLY METHYLATED LOCI BETWEEN CONTROL AND EUGR RATS, REVEALED SIGNIFICANT DIFFERENCE IN CYTOSINE METHYLATION BETWEEN EUGR AND CONTROL RATS. EUGR CHANGES THE CYTOSINE METHYLATION AT APPROXIMATELY 500 LOCI IN MALE RATS AT 9 WEEKS OF AGE, PRECEDING THE DEVELOPMENT OF PULMONARY HYPERTENSION AND THESE REPRESENT THE CANDIDATE LOCI FOR MEDIATING THE PATHOGENESIS OF PULMONARY VASCULAR DISEASE THAT OCCURS LATER IN LIFE. GENE ONTOLOGY ANALYSIS ON DIFFERENTIALLY METHYLATED GENES SHOWED THAT HYPERMETHYLATED GENES IN EUGR ARE VASCULAR DEVELOPMENT-ASSOCIATED GENES AND HYPOMETHYLATED GENES IN EUGR ARE LATE-DIFFERENTIATION-ASSOCIATED AND SIGNAL TRANSDUCTION GENES. WE VALIDATED CANDIDATE DYSREGULATED LOCI WITH THE QUANTITATIVE ASSAYS OF CYTOSINE METHYLATION AND GENE EXPRESSIONS. CONCLUSION: THESE RESULTS DEMONSTRATE THAT EPIGENETICS DYSREGULATION IS A STRONG MECHANISM FOR PROPAGATING THE CELLULAR MEMORY OF EARLY POSTNATAL EVENTS, CAUSING CHANGES IN THE EXPRESSION OF GENES AND LONG-TERM SUSCEPTIBILITY TO PULMONARY HYPERTENSION, AND FURTHER PROVIDING A NEW INSIGHT INTO THE PREVENTION AND TREATMENT OF EUGR-RELATED PULMONARY HYPERTENSION. 2014 5 6137 20 THE EPIGENETICS OF PSYCHOSIS: A STRUCTURED REVIEW WITH REPRESENTATIVE LOCI. THE EVIDENCE FOR AN ENVIRONMENTAL COMPONENT IN CHRONIC PSYCHOTIC DISORDERS IS STRONG AND RESEARCH ON THE EPIGENETIC MANIFESTATIONS OF THESE ENVIRONMENTAL IMPACTS HAS COMMENCED IN EARNEST. IN REVIEWING THIS RESEARCH, THE FOCUS IS ON THREE GENES AS MODELS FOR DIFFERENTIAL METHYLATION, MCHR1, AKT1 AND TDO2, EACH OF WHICH HAVE BEEN INVESTIGATED FOR GENETIC ASSOCIATION WITH PSYCHOTIC DISORDERS. ENVIRONMENTAL FACTORS ASSOCIATED WITH PSYCHOTIC DISORDERS, AND WHICH INTERACT WITH THESE MODEL GENES, ARE EXPLORED IN DEPTH. THE LOCATION OF TRANSCRIPTION FACTOR MOTIFS RELATIVE TO KEY METHYLATION SITES IS EVALUATED FOR PREDICTED GENE EXPRESSION RESULTS, AND FOR OTHER SITES, EVIDENCE IS PRESENTED FOR METHYLATION DIRECTING ALTERNATIVE SPLICING. EXPERIMENTAL RESULTS FROM KEY STUDIES SHOW DIFFERENTIAL METHYLATION: FOR MCHR1, IN PSYCHOSIS CASES VERSUS CONTROLS; FOR AKT1, AS A PRE-EXISTING METHYLATION PATTERN INFLUENCING BRAIN ACTIVATION FOLLOWING ACUTE ADMINISTRATION OF A PSYCHOSIS-ELICITING ENVIRONMENTAL STIMULUS; AND FOR TDO2, IN A PATTERN ASSOCIATED WITH A DEVELOPMENTAL FACTOR OF RISK FOR PSYCHOSIS, IN ALL CASES THE PREDICTED EXPRESSION IMPACT BEING HIGHLY DEPENDENT ON LOCATION. METHYLATION INDUCED BY SMOKING, A CONFOUNDING VARIABLE, EXHIBITS AN INTRIGUING PATTERN FOR ALL THREE GENES. FINALLY, HOW DIFFERENTIAL METHYLATION MESHES WITH DARWINIAN PRINCIPLES IS EXAMINED, IN PARTICULAR AS IT RELATES TO THE "FLEXIBLE STEM" THEORY OF EVOLUTION. 2022 6 2246 28 EPIGENETIC MODULATION OF INFLAMMATION AND SYNAPTIC PLASTICITY PROMOTES RESILIENCE AGAINST STRESS IN MICE. MAJOR DEPRESSIVE DISORDER IS ASSOCIATED WITH ABNORMALITIES IN THE BRAIN AND THE IMMUNE SYSTEM. CHRONIC STRESS IN ANIMALS SHOWED THAT EPIGENETIC AND INFLAMMATORY MECHANISMS PLAY IMPORTANT ROLES IN MEDIATING RESILIENCE AND SUSCEPTIBILITY TO DEPRESSION. HERE, THROUGH A HIGH-THROUGHPUT SCREENING, WE IDENTIFY TWO PHYTOCHEMICALS, DIHYDROCAFFEIC ACID (DHCA) AND MALVIDIN-3'-O-GLUCOSIDE (MAL-GLUC) THAT ARE EFFECTIVE IN PROMOTING RESILIENCE AGAINST STRESS BY MODULATING BRAIN SYNAPTIC PLASTICITY AND PERIPHERAL INFLAMMATION. DHCA/MAL-GLUC ALSO SIGNIFICANTLY REDUCES DEPRESSION-LIKE PHENOTYPES IN A MOUSE MODEL OF INCREASED SYSTEMIC INFLAMMATION INDUCED BY TRANSPLANTATION OF HEMATOPOIETIC PROGENITOR CELLS FROM STRESS-SUSCEPTIBLE MICE. DHCA REDUCES PRO-INFLAMMATORY INTERLEUKIN 6 (IL-6) GENERATIONS BY INHIBITING DNA METHYLATION AT THE CPG-RICH IL-6 SEQUENCES INTRONS 1 AND 3, WHILE MAL-GLUC MODULATES SYNAPTIC PLASTICITY BY INCREASING HISTONE ACETYLATION OF THE REGULATORY SEQUENCES OF THE RAC1 GENE. PERIPHERAL INFLAMMATION AND SYNAPTIC MALADAPTATION ARE IN LINE WITH NEWLY HYPOTHESIZED CLINICAL INTERVENTION TARGETS FOR DEPRESSION THAT ARE NOT ADDRESSED BY CURRENTLY AVAILABLE ANTIDEPRESSANTS. 2018 7 5464 19 RESILIENCE IN LONG-TERM VIRAL INFECTION: GENETIC DETERMINANTS AND INTERACTIONS. VIRUS-INDUCED NEUROLOGICAL SEQUELAE RESULTING FROM INFECTION BY THEILER'S MURINE ENCEPHALOMYELITIS VIRUS (TMEV) ARE USED FOR STUDYING HUMAN CONDITIONS RANGING FROM EPILEPTIC SEIZURES TO DEMYELINATING DISEASE. MOUSE STRAINS ARE TYPICALLY CONSIDERED SUSCEPTIBLE OR RESISTANT TO TMEV INFECTION BASED ON VIRAL PERSISTENCE AND EXTREME PHENOTYPES, SUCH AS DEMYELINATION. WE HAVE IDENTIFIED A BROADER SPECTRUM OF PHENOTYPIC OUTCOMES BY INFECTING STRAINS OF THE GENETICALLY DIVERSE COLLABORATIVE CROSS (CC) MOUSE RESOURCE. WE EVALUATED THE CHRONIC-INFECTION GENE EXPRESSION PROFILES OF HIPPOCAMPI AND THORACIC SPINAL CORDS FOR 19 CC STRAINS IN RELATION TO PHENOTYPIC SEVERITY AND TMEV PERSISTENCE. STRAINS WERE CLUSTERED BASED ON SIMILAR PHENOTYPIC PROFILES AND TMEV LEVELS AT 90 DAYS POST-INFECTION, AND WE CATEGORIZED DISTINCT TMEV RESPONSE PROFILES. THE THREE MOST COMMON PROFILES INCLUDED "RESISTANT" AND "SUSCEPTIBLE," AS BEFORE, AS WELL AS A "RESILIENT" TMEV RESPONSE GROUP WHICH EXPERIENCED BOTH TMEV PERSISTENCE AND MILD NEUROLOGICAL PHENOTYPES EVEN AT 90 DAYS POST-INFECTION. EACH PROFILE HAD A DISTINCT GENE EXPRESSION SIGNATURE, ALLOWING THE IDENTIFICATION OF PATHWAYS AND NETWORKS SPECIFIC TO EACH TMEV RESPONSE GROUP. CC FOUNDER HAPLOTYPES FOR GENES INVOLVED IN THESE PATHWAYS/NETWORKS REVEALED CANDIDATE RESPONSE-SPECIFIC ALLELES. THESE ALLELES DEMONSTRATED PLEIOTROPY AND EPIGENETIC (MIRNA) REGULATION IN LONG-TERM TMEV INFECTION, WITH PARTICULAR RELEVANCE FOR RESILIENT MOUSE STRAINS. 2021 8 3591 23 IMPAIRED ONE CARBON METABOLISM AND DNA METHYLATION IN ALCOHOL TOXICITY. EXCESSIVE ALCOHOL CONSUMPTION IS A PROMINENT PROBLEM AND ONE OF THE MAJOR CAUSES OF MORTALITY AND MORBIDITY AROUND THE WORLD. LONG-TERM, HEAVY ALCOHOL CONSUMPTION IS ASSOCIATED WITH A NUMBER OF DELETERIOUS HEALTH CONSEQUENCES, SUCH AS CANCER, HEART AND LIVER DISEASE, A VARIETY OF NEUROLOGICAL, COGNITIVE, AND BEHAVIORAL DEFICITS. ALCOHOL CONSUMPTION IS ALSO ASSOCIATED WITH DEVELOPMENTAL DEFECTS. THE CAUSES OF ALCOHOL-INDUCED TOXICITY ARE PRESENTLY UNCLEAR. ONE OF THE MECHANISMS UNDERLYING ALCOHOL TOXICITY HAS TO DO WITH ITS INTERACTION WITH FOLIC ACID/HOMOCYSTEINE OR ONE-CARBON METABOLISM (OCM). OCM IS A MAJOR DONOR OF METHYL GROUPS FOR METHYLATION, PARTICULARLY DNA METHYLATION CRITICAL FOR EPIGENETIC REGULATION OF GENE EXPRESSION, AND ITS DISTURBANCE MAY COMPROMISE DNA METHYLATION, THEREBY AFFECTING GENE EXPRESSION. OCM DISTURBANCE MEDIATED BY NUTRIENT DEFICITS IS A WELL-KNOWN RISK FACTOR FOR VARIOUS DISORDERS AND DEVELOPMENTAL DEFECTS (E.G., NEURAL TUBE DEFECTS). IN THIS REVIEW, WE SUMMARIZE THE ROLE OF OCM DISTURBANCE AND ASSOCIATED EPIGENETIC ABERRATIONS IN CHRONIC ALCOHOL-INDUCED TOXICITY. IN THIS REVIEW, WE SUMMARIZE THE ROLE OF ONE-CARBON METABOLISM (OCM) ABERRATIONS IN CHRONIC ALCOHOL-INDUCED TOXICITY. OCM IS A MAJOR DONOR OF METHYL GROUPS FOR METHYLATION REACTIONS, PARTICULARLY DNA METHYLATION CRITICAL FOR EPIGENETIC REGULATION OF GENE EXPRESSION. ALCOHOL INTERFERENCE WITH OCM AND CONSEQUENT REDUCED AVAILABILITY OF METHYL GROUPS, IMPROPER DNA METHYLATION, AND ABERRANT GENE EXPRESSION CAN PLAY A CAUSATIVE ROLE IN ALCOHOL TOXICITY. 2014 9 5468 32 RESISTANCE TRAINING AND REDOX HOMEOSTASIS: CORRELATION WITH AGE-ASSOCIATED GENOMIC CHANGES. REGULAR PHYSICAL ACTIVITY IS EFFECTIVE AS PREVENTION AND TREATMENT FOR DIFFERENT CHRONIC CONDITIONS RELATED TO THE AGEING PROCESSES. IN FACT, A SEDENTARY LIFESTYLE HAS BEEN LINKED TO A WORSENING OF CELLULAR AGEING BIOMARKERS SUCH AS TELOMERE LENGTH (TL) AND/OR SPECIFIC EPIGENETIC CHANGES (E.G. DNA METHYLATION), WITH INCREASE OF THE PROPENSITY TO AGING-RELATED DISEASES AND PREMATURE DEATH. EXTENDING OUR PREVIOUS FINDINGS, WE AIMED TO TEST THE HYPOTHESIS THAT 12 WEEKS OF LOW FREQUENCY, MODERATE INTENSITY, EXPLOSIVE-TYPE RESISTANCE TRAINING (EMRT) MAY ATTENUATE AGE-ASSOCIATED GENOMIC CHANGES. TO THIS AIM, TL, GLOBAL DNA METHYLATION, TRF2, KU80, SIRT1, SIRT2 AND GLOBAL PROTEIN ACETYLATION, AS WELL AS OTHER PROTEINS INVOLVED IN APOPTOTIC PATHWAY (BCL-2, BAX AND CASPASE-3), ANTIOXIDANT RESPONSE (TRXR1 AND MNSOD) AND OXIDATIVE DAMAGE (MYELOPEROXIDASE) WERE EVALUATED BEFORE AND AFTER EMRT IN WHOLE BLOOD OR PERIPHERAL MONONUCLEAR CELLS (PBMCS) OF ELDERLY SUBJECTS. OUR FINDINGS CONFIRM THE POTENTIAL OF EMRT TO INDUCE AN ADAPTIVE CHANGE IN THE ANTIOXIDANT PROTEIN SYSTEMS AT SYSTEMIC LEVEL AND SUGGEST A PUTATIVE ROLE OF RESISTANCE TRAINING IN THE REDUCTION OF GLOBAL DNA METHYLATION. MOREOVER, WE OBSERVED THAT EMRT COUNTERACTS THE TELOMERES' SHORTENING IN A MANNER THAT PROVED TO BE DIRECTLY CORRELATED WITH THE AMELIORATION OF REDOX HOMEOSTASIS AND EFFICACY OF TRAINING REGIME, EVALUATED AS IMPROVEMENT OF BOTH MUSCLE'S POWER/STRENGTH AND FUNCTIONAL PARAMETERS. 2016 10 1584 26 DNA METHYLATION PROFILES OF SELECTED PRO-INFLAMMATORY CYTOKINES IN ALZHEIMER DISEASE. BY MEANS OF FUNCTIONAL GENOMICS ANALYSIS, WE RECENTLY DESCRIBED THE MRNA EXPRESSION PROFILES OF VARIOUS GENES INVOLVED IN THE NEUROINFLAMMATORY RESPONSE IN THE BRAINS OF SUBJECTS WITH LATE-ONSET ALZHEIMER DISEASE (LOAD). SOME OF THESE GENES, NAMELY INTERLEUKIN (IL)-1BETA AND IL-6, SHOWED DISTINCT EXPRESSION PROFILES WITH PEAK EXPRESSION DURING THE FIRST STAGES OF THE DISEASE AND CONTROL-LIKE LEVELS AT LATER STAGES. IL-1BETA AND IL-6 GENES ARE MODULATED BY DNA METHYLATION IN DIFFERENT CHRONIC AND DEGENERATIVE DISEASES; IT IS ALSO WELL KNOWN THAT LOAD MAY HAVE AN EPIGENETIC BASIS. INDEED, WE AND OTHERS HAVE PREVIOUSLY REPORTED GENE-SPECIFIC DNA METHYLATION ALTERATIONS IN LOAD AND IN RELATED ANIMAL MODELS. BASED ON THESE DATA, WE STUDIED THE DNA METHYLATION PROFILES, AT SINGLE CYTOSINE RESOLUTION, OF IL-1BETA AND IL-6 5'-FLANKING REGION BY BISULPHITE MODIFICATION IN THE CORTEX OF HEALTHY CONTROLS AND LOAD PATIENTS AT 2 DIFFERENT DISEASE STAGES: BRAAK I-II/A AND BRAAK V-VI/C. OUR ANALYSIS PROVIDES EVIDENCE THAT NEUROINFLAMMATION IN LOAD IS ASSOCIATED WITH (AND POSSIBLY MEDIATED BY) EPIGENETIC MODIFICATIONS. 2017 11 195 28 ACF CHROMATIN-REMODELING COMPLEX MEDIATES STRESS-INDUCED DEPRESSIVE-LIKE BEHAVIOR. IMPROVED TREATMENT FOR MAJOR DEPRESSIVE DISORDER (MDD) REMAINS ELUSIVE BECAUSE OF THE LIMITED UNDERSTANDING OF ITS UNDERLYING BIOLOGICAL MECHANISMS. IT IS LIKELY THAT STRESS-INDUCED MALADAPTIVE TRANSCRIPTIONAL REGULATION IN LIMBIC NEURAL CIRCUITS CONTRIBUTES TO THE DEVELOPMENT OF MDD, POSSIBLY THROUGH EPIGENETIC FACTORS THAT REGULATE CHROMATIN STRUCTURE. WE ESTABLISH THAT PERSISTENT UPREGULATION OF THE ACF (ATP-UTILIZING CHROMATIN ASSEMBLY AND REMODELING FACTOR) ATP-DEPENDENT CHROMATIN-REMODELING COMPLEX, OCCURRING IN THE NUCLEUS ACCUMBENS OF STRESS-SUSCEPTIBLE MICE AND DEPRESSED HUMANS, IS NECESSARY FOR STRESS-INDUCED DEPRESSIVE-LIKE BEHAVIORS. WE FOUND THAT ALTERED ACF BINDING AFTER CHRONIC STRESS WAS CORRELATED WITH ALTERED NUCLEOSOME POSITIONING, PARTICULARLY AROUND THE TRANSCRIPTION START SITES OF AFFECTED GENES. THESE ALTERATIONS IN ACF BINDING AND NUCLEOSOME POSITIONING WERE ASSOCIATED WITH REPRESSED EXPRESSION OF GENES IMPLICATED IN SUSCEPTIBILITY TO STRESS. TOGETHER, OUR FINDINGS IDENTIFY THE ACF CHROMATIN-REMODELING COMPLEX AS A CRITICAL COMPONENT IN THE DEVELOPMENT OF SUSCEPTIBILITY TO DEPRESSION AND IN REGULATING STRESS-RELATED BEHAVIORS. 2015 12 3002 25 GENETIC, EPIGENETIC AND POSTTRANSCRIPTIONAL MECHANISMS FOR TREATMENT OF MAJOR DEPRESSION: THE 5-HT1A RECEPTOR GENE AS A PARADIGM. MAJOR DEPRESSION AND ANXIETY ARE HIGHLY PREVALENT AND INVOLVE CHRONIC DYSREGULATION OF SEROTONIN, BUT THEY REMAIN POORLY UNDERSTOOD. HERE, WE REVIEW NOVEL TRANSCRIPTIONAL (GENETIC, EPIGENETIC) AND POSTTRANSCRIPTIONAL (MICRORNA, ALTERNATIVE SPLICING) MECHANISMS IMPLICATED IN MENTAL ILLNESS, FOCUSING ON A KEY SEROTONIN-RELATED REGULATOR, THE SEROTONIN 1A (5-HT1A) RECEPTOR. FUNCTIONAL SINGLE-NUCLEOTIDE POLYMORPHISMS AND STRESS-INDUCED DNA METHYLATION OF THE 5-HT1A PROMOTER CONVERGE TO DIFFERENTIALLY ALTER PRE- AND POSTSYNAPTIC 5-HT1A RECEPTOR EXPRESSION ASSOCIATED WITH MAJOR DEPRESSION AND REDUCED THERAPEUTIC RESPONSE TO SEROTONERGIC ANTIDEPRESSANTS. MAJOR DEPRESSION IS ALSO ASSOCIATED WITH ALTERED LEVELS OF SPLICE FACTORS AND MICRORNA, POSTTRANSCRIPTIONAL MECHANISMS THAT REGULATE RNA STABILITY. THE HUMAN 5-HT1A 3'-UNTRANSLATED REGION IS ALTERNATIVELY SPLICED, REMOVING MICRORNA SITES AND INCREASING 5-HT1A EXPRESSION, WHICH IS REDUCED IN MAJOR DEPRESSION AND MAY BE GENOTYPE-DEPENDENT. THUS, THE 5-HT1A RECEPTOR GENE ILLUSTRATES THE CONVERGENCE OF GENETIC, EPIGENETIC AND POSTTRANSCRIPTIONAL MECHANISMS IN GENE EXPRESSION, NEURODEVELOPMENT AND NEUROPLASTICITY, AND MAJOR DEPRESSION. UNDERSTANDING GENE REGULATORY MECHANISMS COULD ENHANCE THE DETECTION, CATEGORIZATION AND PERSONALIZED TREATMENT OF MAJOR DEPRESSION. 2019 13 6334 29 THE ROLE OF DNA METHYLATION AND HYDROXYMETHYLATION IN IMMUNOSENESCENCE. A HEALTHY FUNCTIONING IMMUNE SYSTEM IS CRITICAL TO STAVE OFF INFECTIOUS DISEASES, BUT AS HUMANS AND OTHER ORGANISMS AGE, THEIR IMMUNE SYSTEMS DECLINE. AS A RESULT, DISEASES THAT WERE READILY THWARTED IN EARLY LIFE POSE NONTRIVIAL HARM AND CAN EVEN BE DEADLY IN LATE LIFE. IMMUNOSENESCENCE IS DEFINED AS THE GENERAL DETERIORATION OF THE IMMUNE SYSTEM WITH AGE, AND IT IS CHARACTERIZED BY FUNCTIONAL CHANGES IN HEMATOPOIETIC STEM CELLS (HSCS) AND SPECIFIC BLOOD CELL TYPES AS WELL AS CHANGES IN LEVELS OF NUMEROUS FACTORS, PARTICULARLY THOSE INVOLVED IN INFLAMMATION. POTENTIAL MECHANISMS UNDERLYING IMMUNOSENESCENCE INCLUDE EPIGENETIC CHANGES SUCH AS CHANGES IN DNA METHYLATION (DNAM) AND DNA HYDROXYMETHYLATION (DNAHM) THAT OCCUR WITH AGE. THE PURPOSE OF THIS REVIEW IS TO DESCRIBE WHAT IS CURRENTLY KNOWN ABOUT THE RELATIONSHIP BETWEEN IMMUNOSENESCENCE AND THE AGE-RELATED CHANGES TO DNAM AND DNAHM, AND TO DISCUSS EXPERIMENTAL APPROACHES BEST SUITED TO FILL GAPS IN OUR UNDERSTANDING. 2019 14 3093 30 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 15 6642 28 UNRAVELING THE PATHOGENESIS OF ASTHMA AND CHRONIC OBSTRUCTIVE PULMONARY DISEASE OVERLAP: FOCUSING ON EPIGENETIC MECHANISMS. ASTHMA AND COPD OVERLAP (ACO) IS CHARACTERIZED BY PATIENTS PRESENTING WITH PERSISTENT AIRFLOW LIMITATION AND FEATURES OF BOTH ASTHMA AND COPD. IT IS ASSOCIATED WITH A HIGHER FREQUENCY AND SEVERITY OF EXACERBATIONS, A FASTER LUNG FUNCTION DECLINE, AND A HIGHER HEALTHCARE COST. SYSTEMIC INFLAMMATION IN COPD AND ASTHMA IS DRIVEN BY TYPE 1 T HELPER (TH1) AND TH2 IMMUNE RESPONSES, RESPECTIVELY, BOTH OF WHICH MAY CONTRIBUTE TO AIRWAY REMODELING IN ACO. ACO-RELATED BIOMARKERS CAN BE CLASSIFIED INTO FOUR CATEGORIES: NEUTROPHIL-MEDIATED INFLAMMATION, TH2 CELL RESPONSES, ARACHIDONIC ACID-EICOSANOIDS PATHWAY, AND METABOLITES. GENE-ENVIRONMENT INTERACTIONS ARE KEY CONTRIBUTORS TO THE COMPLEXITY OF ACO AND ARE REGULATED BY EPIGENETIC MECHANISMS, INCLUDING DNA METHYLATION, HISTONE MODIFICATIONS, AND NON-CODING RNAS. THUS, THIS REVIEW FOCUSES ON THE LINK BETWEEN EPIGENETICS AND ACO, AND OUTLINES THE FOLLOWING: (I) INHERITING EPIGENOTYPES WITHOUT CHANGE WITH ENVIRONMENTAL STIMULI, OR EPIGENETIC CHANGES IN RESPONSE TO LONG-TERM EXPOSURE TO INHALED PARTICLES PLUS INTERMITTENT EXPOSURE TO SPECIFIC ALLERGENS; (II) EPIGENETIC MARKERS DISTINGUISHING ACO FROM COPD AND ASTHMA; (III) POTENTIAL EPIGENETIC DRUGS THAT CAN REVERSE OXIDATIVE STRESS, GLUCOCORTICOID INSENSITIVITY, AND CELL INJURY. IMPROVED UNDERSTANDING OF THE EPIGENETIC REGULATIONS HOLDS GREAT VALUE TO GIVE DEEPER INSIGHT INTO THE MECHANISMS, AND CLARIFY THEIR IMPLICATIONS FOR BIOMEDICAL RESEARCH IN ACO. 2022 16 4999 27 PERINATAL PROGRAMMING OF CIRCADIAN CLOCK-STRESS CROSSTALK. AN INTACT COMMUNICATION BETWEEN CIRCADIAN CLOCKS AND THE STRESS SYSTEM IS IMPORTANT FOR MAINTAINING PHYSIOLOGICAL HOMEOSTASIS UNDER RESTING CONDITIONS AND IN RESPONSE TO EXTERNAL STIMULI. THERE IS ACCUMULATING EVIDENCE FOR A RECIPROCAL INTERACTION BETWEEN BOTH-FROM THE SYSTEMIC TO THE MOLECULAR LEVEL. DISRUPTION OF THIS INTERACTION BY EXTERNAL FACTORS SUCH AS SHIFTWORK, JETLAG, OR CHRONIC STRESS INCREASES THE RISK OF DEVELOPING METABOLIC, IMMUNE, OR MOOD DISORDERS. FROM EXPERIMENTS IN RODENTS, WE KNOW THAT BOTH SYSTEMS MATURATE DURING THE PERINATAL PERIOD. DURING THAT TIME, EXOGENOUS FACTORS SUCH AS STRESS OR ALTERATIONS IN THE EXTERNAL PHOTOPERIOD MAY CRITICALLY AFFECT-OR PROGRAM-PHYSIOLOGICAL FUNCTIONS LATER IN LIFE. THIS DEVELOPMENTAL PROGRAMMING PROCESS HAS BEEN ATTRIBUTED TO MATERNAL STRESS SIGNALS REACHING THE EMBRYO, WHICH LASTINGLY CHANGE GENE EXPRESSION THROUGH THE INDUCTION OF EPIGENETIC MECHANISMS. DESPITE THE WELL-KNOWN FUNCTION OF THE ADULT CIRCADIAN SYSTEM IN TEMPORAL COORDINATION OF PHYSIOLOGY AND BEHAVIOR, THE ROLE OF MATERNAL AND EMBRYONIC CIRCADIAN CLOCKS DURING PREGNANCY AND POSTNATAL DEVELOPMENT IS STILL POORLY DEFINED. A BETTER UNDERSTANDING OF THE CIRCADIAN-STRESS CROSSTALK AT DIFFERENT PERIODS OF DEVELOPMENT MAY HELP TO IMPROVE STRESS RESISTANCE AND DEVISE PREVENTIVE AND THERAPEUTIC STRATEGIES AGAINST CHRONIC STRESS-ASSOCIATED DISORDERS. 2018 17 276 31 AGE-RELATED DIFFERENCES IN MONOCYTE DNA METHYLATION AND IMMUNE FUNCTION IN HEALTHY KENYAN ADULTS AND CHILDREN. BACKGROUND: AGE-RELATED CHANGES IN ADAPTIVE AND INNATE IMMUNE CELLS HAVE BEEN ASSOCIATED WITH A DECLINE IN EFFECTIVE IMMUNITY AND CHRONIC, LOW-GRADE INFLAMMATION. EPIGENETIC, TRANSCRIPTIONAL, AND FUNCTIONAL CHANGES IN MONOCYTES OCCUR WITH AGING, THOUGH MOST STUDIES TO DATE HAVE FOCUSED ON DIFFERENCES BETWEEN YOUNG ADULTS AND THE ELDERLY IN POPULATIONS WITH EUROPEAN ANCESTRY; FEW DATA EXIST REGARDING CHANGES THAT OCCUR IN CIRCULATING MONOCYTES DURING THE FIRST FEW DECADES OF LIFE OR IN AFRICAN POPULATIONS. WE ANALYZED DNA METHYLATION PROFILES, CYTOKINE PRODUCTION, AND INFLAMMATORY GENE EXPRESSION PROFILES IN MONOCYTES FROM YOUNG ADULTS AND CHILDREN FROM WESTERN KENYA. RESULTS: WE IDENTIFIED SEVERAL HYPO- AND HYPER-METHYLATED CPG SITES IN MONOCYTES FROM KENYAN YOUNG ADULTS VS. CHILDREN THAT REPLICATED FINDINGS IN THE CURRENT LITERATURE OF DIFFERENTIAL DNA METHYLATION IN MONOCYTES FROM ELDERLY PERSONS VS. YOUNG ADULTS ACROSS DIVERSE POPULATIONS. DIFFERENTIALLY METHYLATED CPG SITES WERE ALSO NOTED IN GENE REGIONS IMPORTANT TO INFLAMMATION AND INNATE IMMUNE RESPONSES. MONOCYTES FROM KENYAN YOUNG ADULTS VS. CHILDREN DISPLAYED INCREASED PRODUCTION OF IL-8, IL-10, AND IL-12P70 IN RESPONSE TO TLR4 AND TLR2/1 STIMULATION AS WELL AS DISTINCT INFLAMMATORY GENE EXPRESSION PROFILES. CONCLUSIONS: THESE FINDINGS COMPLEMENT PREVIOUS REPORTS OF AGE-RELATED METHYLATION CHANGES IN ISOLATED MONOCYTES AND PROVIDE NOVEL INSIGHTS INTO THE ROLE OF AGE-ASSOCIATED CHANGES IN INNATE IMMUNE FUNCTIONS. 2021 18 1749 28 EARLY LIFE INTERVENTIONS CAN SHAPE AGING. IT IS WELL DOCUMENTED THAT THE ENVIRONMENT OF THE DEVELOPING FETUS, INCLUDING AVAILABILITY OF NUTRIENTS AND PRESENCE OF TOXINS, CAN HAVE MAJOR IMPACT ON ADULT PHENOTYPE, AGE-RELATED TRAITS AND RISK OF CHRONIC DISEASE. THERE IS ALSO ACCUMULATING EVIDENCE THAT POSTNATAL ENVIRONMENT CAN IMPACT ADULT CHARACTERISTICS RELATED TO EVOLUTIONARY FITNESS, HEALTH, AND AGING. TO DETERMINE WHETHER EARLY LIFE HORMONAL INTERVENTIONS CAN ALTER TRAJECTORY OF AGING, WE HAVE EXAMINED THE EFFECTS OF EARLY LIFE GROWTH HORMONE (GH) REPLACEMENT THERAPY IN PROP1(DF) (AMES DWARF) MICE WHICH ARE GH DEFICIENT AND REMARKABLY LONG LIVED. TWICE-DAILY GH INJECTIONS BETWEEN THE AGES OF TWO AND EIGHT WEEKS COMPLETELY NORMALIZED ("RESCUED") A NUMBER OF ADULT METABOLIC CHARACTERISTICS BELIEVED TO CONTRIBUTE TO EXTENDED LONGEVITY OF THESE MUTANTS. IMPORTANTLY, LONGEVITY OF AMES DWARF MICE WAS REDUCED BY EARLY LIFE GH TREATMENT. THIS WAS ASSOCIATED WITH HISTONE H3 MODIFICATIONS. WE CONCLUDE THAT THE TRAJECTORY OF MAMMALIAN AGING CAN BE MODIFIED BY EARLY LIFE INTERVENTIONS. MECHANISTIC LINKS AMONG INTERVENTIONS DURING POSTNATAL DEVELOPMENT, ADULT METABOLIC CHARACTERISTICS, AGING, AND LONGEVITY, APPARENTLY INVOLVE EPIGENETIC PHENOMENA. 2022 19 2597 30 EPIGENETICS OF SUBCELLULAR STRUCTURE FUNCTIONING IN THE ORIGIN OF RISK OR RESILIENCE TO COMORBIDITY OF NEUROPSYCHIATRIC AND CARDIOMETABOLIC DISORDERS. MECHANISMS CONTROLLING MITOCHONDRIAL FUNCTION, PROTEIN FOLDING IN THE ENDOPLASMIC RETICULUM (ER) AND NUCLEAR PROCESSES SUCH AS TELOMERE LENGTH AND DNA REPAIR MAY BE SUBJECT TO EPIGENETIC CUES THAT RELATE THE GENOMIC EXPRESSION AND ENVIRONMENTAL EXPOSURES IN EARLY STAGES OF LIFE. THEY MAY ALSO BE INVOLVED IN THE COMORBID APPEARANCE OF CARDIOMETABOLIC (CMD) AND NEUROPSYCHIATRIC DISORDERS (NPD) DURING ADULTHOOD. MITOCHONDRIAL FUNCTION AND PROTEIN FOLDING IN THE ENDOPLASMIC RETICULUM ARE ASSOCIATED WITH OXIDATIVE STRESS AND ELEVATED INTRACELLULAR CALCIUM LEVELS AND MAY ALSO UNDERLIE THE VULNERABILITY FOR COMORBID CMD AND NPD. MITOCHONDRIA PROVIDE KEY METABOLITES SUCH AS NICOTINAMIDE ADENINE DINUCLEOTIDE (NAD+), ATP, ALPHA-KETOGLUTARATE AND ACETYL COENZYME A THAT ARE REQUIRED FOR MANY TRANSCRIPTIONAL AND EPIGENETIC PROCESSES. THEY ARE ALSO A SOURCE OF FREE RADICALS. ON THE OTHER HAND, EPIGENETIC MARKERS IN NUCLEAR DNA DETERMINE MITOCHONDRIAL BIOGENESIS. THE ER IS THE SUBCELLULAR ORGANELLE IN WHICH SECRETORY PROTEINS ARE FOLDED. MANY ENVIRONMENTAL FACTORS STOP THE ABILITY OF CELLS TO PROPERLY FOLD PROTEINS AND MODIFY POST-TRANSLATIONALLY SECRETORY AND TRANSMEMBRANE PROTEINS LEADING TO ENDOPLASMIC RETICULUM STRESS AND OXIDATIVE STRESS. ER FUNCTIONING MAY BE EPIGENETICALLY DETERMINED. CHRONIC ER STRESS IS EMERGING AS A KEY CONTRIBUTOR TO A GROWING LIST OF HUMAN DISEASES, INCLUDING CMD AND NPD. TELOMERE LOSS CAUSES CHROMOSOMAL FUSION, ACTIVATION OF THE CONTROL OF DNA DAMAGE-RESPONSES, UNSTABLE GENOME AND ALTERED STEM CELL FUNCTION, WHICH MAY UNDERLIE THE COMORBIDITY OF CMD AND NPD. THE LENGTH OF TELOMERES IS RELATED TO OXIDATIVE STRESS AND MAY BE EPIGENETICALLY PROGRAMMED. PATHWAYS INVOLVED IN DNA REPAIR MAY BE EPIGENETICALLY PROGRAMMED AND MAY CONTRIBUTE TO DISEASES. IN THIS PAPER, WE DESCRIBE SUBCELLULAR MECHANISMS THAT ARE DETERMINED BY EPIGENETIC MARKERS AND THEIR POSSIBLE RELATION TO THE DEVELOPMENT OF INCREASED SUSCEPTIBILITY TO DEVELOP CMD AND NPD. 2018 20 1182 34 CONVERGING AND DIFFERENTIAL BRAIN PHOSPHOLIPID DYSREGULATION IN THE PATHOGENESIS OF REPETITIVE MILD TRAUMATIC BRAIN INJURY AND ALZHEIMER'S DISEASE. REPETITIVE MILD TRAUMATIC BRAIN INJURY (RMTBI) IS A MAJOR EPIGENETIC RISK FACTOR FOR ALZHEIMER'S DISEASE (AD). THE PRECISE NATURE OF HOW RMTBI LEADS TO OR PRECIPITATES AD PATHOLOGY IS CURRENTLY UNKNOWN. NUMEROUS NEUROLOGICAL CONDITIONS HAVE SHOWN AN IMPORTANT ROLE FOR DYSFUNCTIONAL PHOSPHOLIPID METABOLISM AS A DRIVING FACTOR FOR THE PATHOGENESIS OF NEURODEGENERATIVE DISEASES. HOWEVER, THE PRECISE ROLE IN RMTBI AND AD REMAINS ELUSIVE. WE HYPOTHESIZED THAT A DETAILED PHOSPHOLIPID CHARACTERIZATION WOULD REVEAL PROFILES OF RESPONSE TO INJURY IN TBI THAT OVERLAP WITH AGE-DEPENDENT CHANGES IN AD AND THUS PROVIDE INSIGHTS INTO THE TBI-AD RELATIONSHIP. WE EMPLOYED A LIPIDOMIC APPROACH EXAMINING BRAIN PHOSPHOLIPID PROFILES FROM MOUSE MODELS OF RMTBI AND AD. CORTEX AND HIPPOCAMPAL TISSUE WERE COLLECTED AT 24 H, 3, 6, 9, AND 12 MONTHS POST-RMTBI, AND AT AGES REPRESENTING 'PRE', 'PERI' AND 'POST' ONSET OF AMYLOID PATHOLOGY (I.E., 3, 9, 15 MONTHS-OLD). TOTAL LEVELS OF PHOSPHATIDYLCHOLINE (PC), PHOSPHATIDYLETHANOLAMINE (PE), LYSOPE, AND PHOSPHATIDYLINOSITOL (PI), INCLUDING THEIR MONOUNSATURATED, POLYUNSATURATED AND SATURATED FATTY ACID (FA) CONTAINING SPECIES WERE SIGNIFICANTLY INCREASED AT ACUTE AND/OR CHRONIC TIME POINTS POST-INJURY IN BOTH BRAIN REGIONS. HOWEVER, LEVELS OF MOST PHOSPHOLIPID SPECIES IN PS1/APP MICE WERE NOMINAL IN THE HIPPOCAMPUS, WHILE IN THE CORTEX, LEVELS WERE SIGNIFICANTLY DECREASED AT AGES POST-ONSET OF AMYLOID PATHOLOGY. SPHINGOMYELIN AND LYSOPC LEVELS SHOWED COINCIDENTAL TRENDS IN OUR RMTBI AND AD MODELS WITHIN THE HIPPOCAMPUS, AN INCREASE AT ACUTE AND/OR CHRONIC TIME POINTS EXAMINED. THE RATIO OF ARACHIDONIC ACID (OMEGA-6 FA) TO DOCOSAHEXAENOIC ACID (OMEGA-3 FA)-CONTAINING PE SPECIES WAS INCREASED AT EARLY TIME POINTS IN THE HIPPOCAMPUS OF INJURED VERSUS SHAM MICE, AND IN PS1/APP MICE THERE WAS A COINCIDENTAL INCREASE COMPARED TO WILD TYPE LITTERMATES AT ALL TIME POINTS. THIS STUDY DEMONSTRATES SOME OVERLAPPING AND DIVERSE PHOSPHOLIPID PROFILES IN RMTBI AND AD MODELS. FUTURE STUDIES ARE REQUIRED TO CORROBORATE OUR FINDINGS IN HUMAN POST-MORTEM TISSUE. INVESTIGATION OF SECONDARY MECHANISMS TRIGGERED BY ABERRANT DOWNSTREAM ALTERATIONS IN BIOACTIVE METABOLITES OF THESE PHOSPHOLIPIDS, AND THEIR MODULATION AT THE APPROPRIATE TIME-WINDOWS OF OPPORTUNITY COULD HELP FACILITATE DEVELOPMENT OF NOVEL THERAPEUTIC STRATEGIES TO AMELIORATE THE NEURODEGENERATIVE CONSEQUENCES OF RMTBI OR THE POTENTIAL TRIGGERING OF AD PATHOGENESIS BY RMTBI. 2019