1 5398 103 REDUCED MOUSE ALLERGEN IS ASSOCIATED WITH EPIGENETIC CHANGES IN REGULATORY GENES, BUT NOT MOUSE SENSITIZATION, IN ASTHMATIC CHILDREN. CHRONIC EXPOSURE TO MOUSE ALLERGEN MAY CONTRIBUTE GREATLY TO THE INNER-CITY ASTHMA BURDEN. WE HYPOTHESIZED THAT REDUCING MOUSE ALLERGEN EXPOSURE MAY MODULATE THE IMMUNOPATHOLOGY UNDERLYING SYMPTOMATIC PEDIATRIC ALLERGIC ASTHMA, AND THAT THIS OCCURS THROUGH EPIGENETIC REGULATION. TO TEST THIS HYPOTHESIS, WE STUDIED A COHORT OF MOUSE SENSITIZED, PERSISTENT ASTHMATIC INNER-CITY CHILDREN UNDERGOING MOUSE ALLERGEN-TARGETED INTEGRATED PEST MANAGEMENT (IPM) VS EDUCATION IN A RANDOMIZED CONTROLLED INTERVENTION TRIAL. WE FOUND THAT DECREASING MOUSE ALLERGEN EXPOSURE, BUT NOT COCKROACH, WAS ASSOCIATED WITH REDUCED FOXP3 BUCCAL DNA PROMOTER METHYLATION, BUT THIS WAS UNRELATED TO MOUSE SPECIFIC IGE PRODUCTION. THIS FINDING SUGGESTS THAT THE ENVIRONMENTAL EPIGENETIC REGULATION OF AN IMMUNOMODULATORY GENE MAY OCCUR FOLLOWING CHANGING ALLERGEN EXPOSURES IN SOME HIGHLY EXPOSED COHORTS. GIVEN THE CLINICAL AND PUBLIC HEALTH IMPORTANCE OF INNER-CITY PEDIATRIC ASTHMA AND THE POTENTIAL IMPACT OF ENVIRONMENTAL INTERVENTIONS, FURTHER STUDIES WILL BE NEEDED TO CORROBORATE CHANGES IN EPIGENETIC REGULATION FOLLOWING CHANGING EXPOSURES OVER TIME, AND DETERMINE THEIR IMPACT ON ASTHMA MORBIDITY IN SUSCEPTIBLE CHILDREN. 2017 2 343 36 ALTERATIONS OF THE LUNG METHYLOME IN ALLERGIC AIRWAY HYPER-RESPONSIVENESS. ASTHMA IS A CHRONIC AIRWAY DISORDER CHARACTERIZED BY RECURRENT ATTACKS OF BREATHLESSNESS AND WHEEZING, AFFECTING 300 MILLION PEOPLE AROUND THE WORLD (AVAILABLE AT: WWW.WHO.INT). TO DATE, GENETIC FACTORS ASSOCIATED WITH ASTHMA SUSCEPTIBILITY HAVE BEEN UNABLE TO EXPLAIN THE FULL ETIOLOGY OF ASTHMA. RECENT STUDIES HAVE DEMONSTRATED THAT THE EPIGENETIC DISRUPTION OF GENE EXPRESSION PLAYS AN EQUALLY IMPORTANT ROLE IN THE DEVELOPMENT OF ASTHMA THROUGH INTERACTION WITH OUR ENVIRONMENT. WE SENSITIZED 6-WEEK-OLD C57BL/6J MICE WITH HOUSE-DUST-MITE (HDM) EXTRACTS INTRAPERITONEALLY FOLLOWED BY 5 WEEKS OF EXPOSURE TO HDM CHALLENGES (THREE TIMES A WEEK) INTRATRACHEALLY. HDM-EXPOSED MICE SHOWED AN INCREASE IN AIRWAY HYPER-RESPONSIVENESS (AHR) AND INFLAMMATION TOGETHER WITH STRUCTURAL REMODELING OF THE AIRWAYS. WE APPLIED METHYLATED DNA IMMUNOPRECIPITATION-NEXT GENERATION SEQUENCING (MEDIP-SEQ) FOR PROFILING OF DNA METHYLATION CHANGES IN THE LUNGS IN RESPONSE TO HDM. WE OBSERVED ABOUT 20 MILLION READS BY A SINGLE-RUN OF MASSIVE PARALLEL SEQUENCING. WE PERFORMED BIOINFORMATICS AND PATHWAY ANALYSIS ON THE RAW SEQUENCING DATA TO IDENTIFY DIFFERENTIALLY METHYLATED CANDIDATE GENES IN HDM-EXPOSED MICE. SPECIFICALLY, WE HAVE REVEALED THAT THE TRANSFORMING GROWTH FACTOR BETA SIGNALING PATHWAY IS EPIGENETICALLY MODULATED BY CHRONIC EXPOSURE TO HDM. HERE, WE DEMONSTRATED THAT A SPECIFIC ALLERGEN MAY PLAY A ROLE IN AHR THROUGH AN EPIGENETIC MECHANISM BY DISRUPTING THE EXPRESSION OF GENES IN LUNGS THAT MIGHT BE INVOLVED IN AIRWAY INFLAMMATION AND REMODELING. OUR FINDINGS PROVIDE NEW INSIGHTS INTO THE POTENTIAL MECHANISMS BY WHICH ENVIRONMENTAL ALLERGENS INDUCE ALLERGIC ASTHMA AND SUCH INSIGHTS MAY ASSIST IN THE DEVELOPMENT OF NOVEL PREVENTIVE AND THERAPEUTIC OPTIONS FOR THIS DEBILITATIVE DISEASE. 2014 3 2022 37 EPIGENETIC CHANGES ASSOCIATED WITH DISEASE PROGRESSION IN A MOUSE MODEL OF CHILDHOOD ALLERGIC ASTHMA. DEVELOPMENT OF ASTHMA IN CHILDHOOD IS LINKED TO VIRAL INFECTIONS OF THE LOWER RESPIRATORY TRACT IN EARLY LIFE, WITH SUBSEQUENT CHRONIC EXPOSURE TO ALLERGENS. PROGRESSION TO PERSISTENT ASTHMA IS ASSOCIATED WITH A TH2-BIASED IMMUNOLOGICAL RESPONSE AND STRUCTURAL REMODELLING OF THE AIRWAYS. THE UNDERLYING MECHANISMS ARE UNCLEAR, BUT COULD INVOLVE EPIGENETIC CHANGES. TO INVESTIGATE THIS, WE EMPLOYED A RECENTLY DEVELOPED MOUSE MODEL IN WHICH SELF-LIMITED NEONATAL INFECTION WITH A PNEUMOVIRUS, FOLLOWED BY SENSITISATION TO OVALBUMIN VIA THE RESPIRATORY TRACT AND LOW-LEVEL CHRONIC CHALLENGE WITH AEROSOLISED ANTIGEN, LEADS TO DEVELOPMENT OF AN ASTHMATIC PHENOTYPE. WE ASSESSED EXPRESSION OF MICRORNA BY CELLS IN THE PROXIMAL AIRWAYS, COMPARING CHANGES OVER THE PERIOD OF DISEASE PROGRESSION, AND USED TARGET PREDICTION DATABASES TO IDENTIFY GENES LIKELY TO BE UP- OR DOWNREGULATED AS A CONSEQUENCE OF ALTERED REGULATION OF MICRORNA. IN PARALLEL, WE ASSESSED DNA METHYLATION IN PULMONARY CD4(+) T CELLS. WE FOUND THAT A LIMITED NUMBER OF MICRORNAS EXHIBITED MARKED UP- OR DOWNREGULATION FOLLOWING EARLY-LIFE INFECTION AND SENSITISATION, FOR MANY OF WHICH THE LEVELS OF EXPRESSION WERE FURTHER CHANGED FOLLOWING CHRONIC CHALLENGE WITH THE SENSITIZING ANTIGEN. TARGETS OF THESE MICRORNAS INCLUDED GENES INVOLVED IN IMMUNE OR INFLAMMATORY RESPONSES (E.G. GATA3, KITL) AND IN TISSUE REMODELLING (E.G. IGF1, TGFBR1), AS WELL AS GENES FOR VARIOUS TRANSCRIPTION FACTORS AND SIGNALLING PROTEINS. IN PULMONARY CD4(+) T CELLS, THERE WAS SIGNIFICANT DEMETHYLATION AT PROMOTER SITES FOR INTERLEUKIN-4 AND INTERFERON-GAMMA, THE LATTER INCREASING FOLLOWING CHRONIC CHALLENGE. WE CONCLUDE THAT, IN THIS MODEL, PROGRESSION TO AN ASTHMATIC PHENOTYPE IS LINKED TO EPIGENETIC REGULATION OF GENES ASSOCIATED WITH INFLAMMATION AND STRUCTURAL REMODELLING, AND WITH T-CELL COMMITMENT TO A TH2 IMMUNOLOGICAL RESPONSE. EPIGENETIC CHANGES ASSOCIATED WITH THIS PATTERN OF GENE ACTIVATION MIGHT PLAY A ROLE IN THE DEVELOPMENT OF CHILDHOOD ASTHMA. 2013 4 276 23 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 5 2279 32 EPIGENETIC REGULATION IN ALLERGIC DISEASES AND RELATED STUDIES. ASTHMA, A CHRONIC INFLAMMATORY DISORDER OF THE AIRWAY, HAS FEATURES OF BOTH HERITABILITY AS WELL AS ENVIRONMENTAL INFLUENCES WHICH CAN BE INTRODUCED IN UTERO EXPOSURES AND MODIFIED THROUGH AGING, AND THE FEATURES MAY ATTRIBUTE TO EPIGENETIC REGULATION. EPIGENETIC REGULATION EXPLAINS THE ASSOCIATION BETWEEN EARLY PRENATAL MATERNAL SMOKING AND LATER ASTHMA-RELATED OUTCOMES. EPIGENETIC MARKS (DNA METHYLATION, MODIFICATIONS OF HISTONE TAILS OR NONCODING RNAS) WORK WITH OTHER COMPONENTS OF THE CELLULAR REGULATORY MACHINERY TO CONTROL THE LEVELS OF EXPRESSED GENES, AND SEVERAL ALLERGY- AND ASTHMA-RELATED GENES HAVE BEEN FOUND TO BE SUSCEPTIBLE TO EPIGENETIC REGULATION, INCLUDING GENES IMPORTANT TO T-EFFECTOR PATHWAYS (IFN-GAMMA, INTERLEUKIN [IL] 4, IL-13, IL-17) AND T-REGULATORY PATHWAYS (FOXP3). THEREFORE, THE MECHANISM BY WHICH EPIGENETIC REGULATION CONTRIBUTES TO ALLERGIC DISEASES IS A CRITICAL ISSUE. IN THE PAST MOST PUBLISHED EXPERIMENTAL WORK, WITH FEW EXCEPTIONS, HAS ONLY COMPRISED SMALL OBSERVATIONAL STUDIES AND MODELS IN CELL SYSTEMS AND ANIMALS. HOWEVER, VERY RECENTLY EXCITING AND ELEGANT EXPERIMENTAL STUDIES AND NOVEL TRANSLATIONAL RESEARCH WORKS WERE PUBLISHED WITH NEW AND ADVANCED TECHNOLOGIES INVESTIGATING EPIGENETIC MARK ON A GENOMIC SCALE AND COMPREHENSIVE APPROACHES TO DATA ANALYSIS. INTERESTINGLY, A POTENTIAL LINK BETWEEN EXPOSURE TO ENVIRONMENTAL POLLUTANTS AND THE OCCURRENCE OF ALLERGIC DISEASES IS REVEALED RECENTLY, PARTICULAR IN DEVELOPED AND INDUSTRIALIZED COUNTRIES, AND ENDOCRINE DISRUPTING CHEMICALS (EDCS) AS ENVIRONMENTAL HORMONE MAY PLAY A KEY ROLE. THIS REVIEW ADDRESSES THE IMPORTANT QUESTION OF HOW EDCS (NONYLPHENOL, 4 OCTYLPHENOL, AND PHTHALATES) INFLUENCES ON ASTHMA-RELATED GENE EXPRESSION VIA EPIGENETIC REGULATION IN IMMUNE CELLS, AND HOW ANTI-ASTHMATIC AGENTS PROHIBIT EXPRESSION OF INFLAMMATORY GENES VIA EPIGENETIC MODIFICATION. THE DISCOVERY AND VALIDATION OF EPIGENETIC BIOMARKERS LINKING EXPOSURE TO ALLERGIC DISEASES MIGHT LEAD TO BETTER EPIGENOTYPING OF RISK, PROGNOSIS, TREATMENT PREDICTION, AND DEVELOPMENT OF NOVEL THERAPIES. 2014 6 1567 31 DNA METHYLATION OF THE KLF14 GENE REGION IN WHOLE BLOOD CELLS PROVIDES PREDICTION FOR THE CHRONIC INFLAMMATION IN THE ADIPOSE TISSUE. KRUPPEL-LIKE FACTOR 14 (KLF14) GENE, WHICH APPEARS TO BE A MASTER REGULATOR OF GENE EXPRESSION IN THE ADIPOSE TISSUE AND HAVE PREVIOUSLY BEEN ASSOCIATED WITH BMI AND TYPE 2 DIABETES (T2D) BY LARGE GENOME-WIDE ASSOCIATION STUDIES. IN ORDER TO FIND PREDICTIVE BIOMARKERS FOR THE DEVELOPMENT OF T2D, IT IS NECESSARY TO TAKE EPIGENOMIC CHANGES AFFECTED BY ENVIRONMENTAL FACTORS INTO ACCOUNT. THIS STUDY FOCUSES ON AGEING AND OBESITY, WHICH ARE T2D RISK FACTORS, AND EXAMINES EPIGENETIC CHANGES AND INFLAMMATORY CHANGES. WE INVESTIGATED DNA METHYLATION CHANGES IN THE KLF14 PROMOTER REGION IN DIFFERENT ORGANS OF MICE FOR COMPARING AGING AND WEIGHT. WE FOUND THAT METHYLATION LEVELS OF THESE SITES WERE INCREASED WITH AGING AND WEIGHT IN THE SPLEEN, THE ADIPOSE TISSUE, THE KIDNEY, THE LUNG, THE COLON AND THE WHOLE BLOOD CELLS. IN ADDITION, IN THE SPLEEN, THE ADIPOSE TISSUE AND THE WHOLE BLOOD, THESE EPIGENETIC CHANGES WERE ALSO SIGNIFICANTLY ASSOCIATED WITH INFLAMMATORY LEVELS. MOREOVER, NOT ONLY KLF14, BUT ALSO EXPRESSION LEVELS OF SOME DOWNSTREAM GENES WERE DECREASED WITH METHYLATION IN THE SPLEEN, THE ADIPOSE TISSUE AND THE WHOLE BLOOD CELLS. TAKEN TOGETHER, OUR RESULTS SUGGEST THAT METHYLATION CHANGES OF KLF14 IN THOSE TISSUES MAY BE ASSOCIATED WITH CHANGES IN GENE EXPRESSION AND INFLAMMATION ON THE ADIPOSE TISSUE OF OBESITY AND T2D. IN ADDITION, THE METHYLATION CHANGES IN THE WHOLE BLOOD CELLS MAY SERVE AS A PREDICTIVE EPIGENETIC BIOMARKER FOR THE DEVELOPMENT OF T2D. 2018 7 6137 22 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 8 6720 27 VITAMIN D METABOLISM GENES ARE DIFFERENTIALLY METHYLATED IN INDIVIDUALS WITH CHRONIC KNEE PAIN. CONTEXT: RECENT EVIDENCE SUGGESTS THAT VITAMIN D MAY INTERACT WITH THE EPIGENOME AND PLAY A ROLE IN THE PAIN EXPERIENCE. IN ORDER FOR PROPER FUNCTIONING TO OCCUR, THERE MUST BE AN ADEQUATE LEVEL OF VITAMIN D PRESENT, MADE POSSIBLE BY ENZYMATIC REACTIONS THAT ALLOW VITAMIN D TO BE BIOLOGICALLY ACTIVE. THE PURPOSE OF THIS STUDY WAS TO EXPLORE THE EPIGENETIC LANDSCAPE OF GENES INVOLVED IN VITAMIN D METABOLISM IN INDIVIDUALS WITH AND WITHOUT CHRONIC KNEE PAIN. PROCEDURES: COMMUNITY-DWELLING INDIVIDUALS RECRUITED AS PART OF A LARGER STUDY FOCUSED ON KNEE PAIN PROVIDED DEMOGRAPHIC, CLINICAL AND PAIN-RELATED INFORMATION, AS WELL AS AN INTRAVENOUS BLOOD SAMPLE TO DETERMINE DNA METHYLATION LEVELS AT CPG SITES. MAIN FINDINGS: THERE WERE DIFFERENCES IN DNA METHYLATION BETWEEN THOSE WITH AND WITHOUT PAIN IN GENES THAT CODE FOR ENZYMES RELATED TO VITAMIN D METABOLISM: CYP24A1 (24-HYDROXYLASE) AND CYP27B1 (1-?-HYDROXYLASE). THERE WAS ALSO HYPERMETHYLATION ON THE GENE THAT CODES FOR THE VITAMIN D RECEPTOR (VDR). PRINCIPAL CONCLUSIONS: THE PRESENCE OF CHRONIC PAIN IS ASSOCIATED WITH EPIGENETIC MODIFICATIONS IN GENES RESPONSIBLE FOR THE EXPRESSION OF ENZYMES INVOLVED IN VITAMIN D METABOLISM AND CELLULAR FUNCTION. THESE RESULTS LAY GROUNDWORK IN UNDERSTANDING THE MECHANISM UNDERLYING THE ASSOCIATION BETWEEN VITAMIN D AND CHRONIC PAIN. 2023 9 3290 28 HIGH CORTISOL IN 5-YEAR-OLD CHILDREN CAUSES LOSS OF DNA METHYLATION IN SINE RETROTRANSPOSONS: A POSSIBLE ROLE FOR ZNF263 IN STRESS-RELATED DISEASES. BACKGROUND: CHILDHOOD STRESS LEADS TO INCREASED RISK OF MANY ADULT DISEASES, SUCH AS MAJOR DEPRESSION AND CARDIOVASCULAR DISEASE. STUDIES SHOW THAT ADULTS WITH EXPERIENCED CHILDHOOD STRESS HAVE SPECIFIC EPIGENETIC CHANGES, BUT TO UNDERSTAND THE PATHWAYS THAT LEAD TO DISEASE, WE ALSO NEED TO STUDY THE EPIGENETIC LINK PROSPECTIVELY IN CHILDREN. RESULTS: HERE, WE STUDIED A HOMOGENOUS GROUP OF 48 5-YEAR-OLD CHILDREN. BY COMBINING HAIR CORTISOL MEASUREMENTS (A WELL-DOCUMENTED BIOMARKER FOR CHRONIC STRESS), WITH WHOLE-GENOME DNA-METHYLATION SEQUENCING, WE SHOW THAT HIGH CORTISOL ASSOCIATES WITH A GENOME-WIDE DECREASE IN DNA METHYLATION AND TARGETS SHORT INTERSPERSED NUCLEAR ELEMENTS (SINES; A TYPE OF RETROTRANSPOSON) AND GENES IMPORTANT FOR CALCIUM TRANSPORT: PHENOMENA COMMONLY AFFECTED IN STRESS-RELATED DISEASES AND IN BIOLOGICAL AGING. MORE IMPORTANTLY, WE IDENTIFY A ZINC-FINGER TRANSCRIPTION FACTOR, ZNF263, WHOSE BINDING SITES WHERE HIGHLY OVERREPRESENTED IN REGIONS EXPERIENCING METHYLATION LOSS. THIS TYPE OF ZINC-FINGER PROTEIN HAS PREVIOUSLY SHOWN TO BE INVOLVED IN THE DEFENSE AGAINST RETROTRANSPOSONS. CONCLUSIONS: OUR RESULTS SHOW THAT STRESS IN PRESCHOOL CHILDREN LEADS TO CHANGES IN DNA METHYLATION SIMILAR TO THOSE SEEN IN BIOLOGICAL AGING. WE SUGGEST THAT THIS MAY AFFECT FUTURE DISEASE SUSCEPTIBILITY BY ALTERATIONS IN THE EPIGENETIC MECHANISMS THAT KEEP RETROTRANSPOSONS DORMANT. FUTURE TREATMENTS FOR STRESS- AND AGE-RELATED DISEASES MAY THEREFORE SEEK TO TARGET ZINC-FINGER PROTEINS THAT EPIGENETICALLY CONTROL RETROTRANSPOSON REACTIVATION, SUCH AS ZNF263. 2015 10 1584 19 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 1524 22 DNA METHYLATION CHANGES IN CYSTIC FIBROSIS: CAUSE OR CONSEQUENCE? TWIN AND SIBLING STUDIES HAVE SHOWN THAT LUNG DISEASE SEVERITY IS VARIABLE AMONG CYSTIC FIBROSIS (CF) PATIENTS AND AFFECTED TO THE SAME EXTENT BY GENETIC AND NONHERITABLE FACTORS. GENETIC FACTORS HAVE BEEN THOROUGHLY ASSESSED, WHEREAS THE MOLECULAR MECHANISMS WHEREBY NONHERITABLE FACTORS CONTRIBUTE TO THE PHENOTYPIC VARIABILITY OF CF PATIENTS ARE STILL UNKNOWN. EPIGENETIC MODIFICATIONS MAY REPRESENT THE MISSING LINK BETWEEN NONHERITABLE FACTORS AND PHENOTYPIC VARIATION IN CF. HEREIN, WE REVIEW RECENT STUDIES SHOWING THAT DNA METHYLATION IS ALTERED IN CF AND WE ADDRESS THREE POSSIBLE FACTORS RESPONSIBLE FOR THESE VARIATIONS: (I) OVERPRODUCTION OF REACTIVE OXYGEN SPECIES, (II) DEPLETION OF DNA METHYLATION COFACTORS AND (III) SUSCEPTIBILITY TO ACUTE AND CHRONIC BACTERIAL INFECTIONS. ALSO, WE HYPOTHESIZE THAT THE UNIQUE DNA METHYLATION PROFILE OF EACH PATIENT CAN MODULATE THE PHENOTYPE AND DISCUSS THE INTEREST OF IMPLEMENTING INTEGRATED GENOMIC, EPIGENOMIC AND TRANSCRIPTOMIC STUDIES TO FURTHER UNDERSTAND THE CLINICAL DIVERSITY OF CF PATIENTS (GRAPHICAL ABSTRACT). 2020 12 5894 32 T CELL EPIGENETIC REMODELING AND ACCELERATED EPIGENETIC AGING ARE LINKED TO LONG-TERM IMMUNE ALTERATIONS IN CHILDHOOD CANCER SURVIVORS. BACKGROUND: CANCER TREATMENTS HAVE SUBSTANTIALLY IMPROVED CHILDHOOD CANCER SURVIVAL BUT ARE ACCOMPANIED BY LONG-TERM COMPLICATIONS, NOTABLY CHRONIC INFLAMMATORY DISEASES. WE HYPOTHESIZE THAT CANCER TREATMENTS COULD LEAD TO LONG-TERM EPIGENETIC CHANGES IN IMMUNE CELLS, RESULTING IN INCREASED PREVALENCE OF INFLAMMATORY DISEASES IN CANCER SURVIVORS. RESULTS: TO TEST THIS HYPOTHESIS, WE ESTABLISHED THE EPIGENETIC AND TRANSCRIPTOMIC PROFILES OF IMMUNE CELLS FROM 44 CHILDHOOD CANCER SURVIVORS (CCS, > 16 YEARS OLD) ON FULL REMISSION (> 5 YEARS) WHO HAD RECEIVED CHEMOTHERAPY ALONE OR IN COMBINATION WITH TOTAL BODY IRRADIATION (TBI) AND HEMATOPOIETIC STEM CELL TRANSPLANT (HSCT). WE FOUND THAT MORE THAN 10 YEARS POST-TREATMENT, CCS TREATED WITH TBI/HSCT SHOWED AN ALTERED DNA METHYLATION SIGNATURE IN T CELL, PARTICULARLY AT GENES CONTROLLING IMMUNE AND INFLAMMATORY PROCESSES AND OXIDATIVE STRESS. DNA METHYLATION REMODELING IN T CELL WAS PARTIALLY ASSOCIATED WITH CHRONIC EXPRESSION CHANGES OF NEARBY GENES, INCREASED FREQUENCY OF TYPE 1 CYTOKINE-PRODUCING T CELL, ELEVATED SYSTEMIC LEVELS OF THESE CYTOKINES, AND OVER-ACTIVATION OF RELATED SIGNALING PATHWAYS. SURVIVORS EXPOSED TO TBI/HSCT WERE FURTHER CHARACTERIZED BY AN EPIGENETIC-AGING-SIGNATURE OF T CELL CONSISTENT WITH ACCELERATED EPIGENETIC AGING. TO INVESTIGATE THE POTENTIAL CONTRIBUTION OF IRRADIATION TO THESE CHANGES, WE ESTABLISHED TWO CELL CULTURE MODELS. WE IDENTIFIED THAT RADIATION PARTIALLY RECAPITULATED THE IMMUNE CHANGES OBSERVED IN SURVIVORS THROUGH A BYSTANDER EFFECT THAT COULD BE MEDIATED BY CIRCULATING FACTORS. CONCLUSION: CANCER TREATMENTS, IN PARTICULAR TBI/HSCT, ARE ASSOCIATED WITH LONG-TERM IMMUNE DISTURBANCES. WE PROPOSE THAT EPIGENETIC REMODELING OF IMMUNE CELLS FOLLOWING CANCER THERAPY AUGMENTS INFLAMMATORY- AND AGE-RELATED DISEASES, INCLUDING METABOLIC COMPLICATIONS, IN CHILDHOOD CANCER SURVIVORS. 2018 13 2776 29 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 14 1162 33 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 15 6226 17 THE LINK BETWEEN EPIGENETICS, PAIN SENSITIVITY AND CHRONIC PAIN. INCREASING EVIDENCE SUGGESTS AN ASSOCIATION BETWEEN GENE EXPRESSION AND CLINICAL PAIN. EPIGENETIC MODIFICATIONS ARE THE MAIN MODULATORS OF GENE EXPRESSION OR PROTEIN TRANSLATION IN RESPONSE TO ENVIRONMENTAL STIMULI AND PATHOPHYSIOLOGICAL CONDITIONS. PRECLINICAL AND CLINICAL STUDIES INDICATE THAT EPIGENETIC MODIFICATIONS COULD ALSO IMPACT THE DEVELOPMENT OF PAIN, THE TRANSITION FROM ACUTE TO CHRONIC PAIN, AND THE MAINTENANCE HEREOF. 2022 16 6195 30 THE IMPACT OF RECENT ALCOHOL USE ON GENOME WIDE DNA METHYLATION SIGNATURES. CHRONIC ALCOHOL INTAKE IS ASSOCIATED WITH A WIDE VARIETY OF ADVERSE HEALTH OUTCOMES INCLUDING DEPRESSION, DIABETES, AND HEART DISEASE. UNFORTUNATELY, THE MOLECULAR MECHANISMS THROUGH WHICH THESE EFFECTS ARE CONVEYED ARE NOT CLEARLY UNDERSTOOD. TO EXAMINE THE POTENTIAL ROLE OF EPIGENETIC FACTORS IN THIS PROCESS, WE EXAMINED THE RELATIONSHIP OF RECENT ALCOHOL INTAKE TO GENOME WIDE METHYLATION PATTERNS USING THE ILLUMINA 450 METHYLATION BEAD CHIP AND LYMPHOBLAST DNA DERIVED FROM 165 FEMALE SUBJECTS PARTICIPATING IN THE IOWA ADOPTION STUDIES. WE FOUND THAT THE PATTERN OF ALCOHOL USE OVER THE 6-MONTHS IMMEDIATELY PRIOR TO PHLEBOTOMY WAS ASSOCIATED WITH, SEVERITY-DEPENDENT CHANGES IN THE DEGREE OF GENOME WIDE METHYLATION THAT PREFERENTIALLY HYPERMETHYLATE THE CENTRAL PORTION OF CPG ISLANDS WITH METHYLATION AT CG05600126, A PROBE IN ABR, AND THE 5' UNTRANSLATED REGION OF BLCAP ATTAINING GENOME WIDE SIGNIFICANCE IN TWO POINT AND SLIDING WINDOW ANALYSES OF PROBE METHYLATION DATA, RESPECTIVELY. WE CONCLUDE THAT RECENT ALCOHOL USE IS ASSOCIATED WITH WIDESPREAD CHANGES IN DNA METHYLATION IN WOMEN AND THAT FURTHER STUDY TO CONFIRM THESE FINDINGS AND DETERMINE THEIR RELATIONSHIP TO SOMATIC FUNCTION ARE IN ORDER. 2012 17 3034 37 GENETICS/EPIGENETICS/ALLERGY: THE GUN IS LOADED ... BUT WHAT PULLS THE TRIGGER? BACKGROUND: THE ALLERGIC DISEASES COMPRISE A GROUP OF CHRONIC INFLAMMATORY CONDITIONS THAT DISPLAY A BROAD SPECTRUM OF CLINICAL MANIFESTATIONS PRIMARILY MEDIATED BY IMMUNOGLOBULIN E (IGE). THE PREVALENCE AND SEVERITY OF THESE IGE-MEDIATED ALLERGIC DISORDERS HAVE INCREASED DRAMATICALLY OVER THE PAST FEW DECADES AND ARE BECOMING A GLOBAL HEALTH PROBLEM. ALTHOUGH GENETICS PLAYS AN IMPORTANT ROLE IN DETERMINING WHO DEVELOPS THESE ATOPIC DISORDERS, GENETICS ALONE CANNOT FULLY EXPLAIN THIS RAPID GROWTH. RESULTS OF NUMEROUS STUDIES HAVE INDICATED THAT EPIGENETICS PLAYS A MAJOR PATHOGENETIC ROLE BY SUPERIMPOSING ITS EFFECTS ABOVE THE DNA PRIMAL GENETIC MOLECULE THROUGH INTERACTIONS WITH AND BETWEEN VARIOUS SUSCEPTIBILITY GENES, IMMUNOLOGIC INFLUENCES, AND ENVIRONMENTAL FACTORS. OBJECTIVE: IN THIS ARTICLE, THE IMPORTANCE AND RELATIONSHIPS OF GENETICS AND EPIGENETICS TO AN UNDERSTANDING OF THE IMMUNE SYSTEM IN HEALTH AND IN DISEASE WERE REVIEWED TOGETHER WITH THE PRINCIPLES AND MECHANISMS THAT UNDERLIE THESE ENTITIES AND WHICH RELATE TO CLINICAL ALLERGY PRACTICE. A SPECIFIC FOCUS OF THE ARTICLE WAS DIRECTED TO THE RECENT RECOGNITION THAT THE IGE-DRIVEN ATOPIC DISORDERS ARE DRIVEN BY ABERRANT IMMUNE RESPONSES IN WHICH CD25(+) FORKHEAD BOX P3(+) (FOXP3(+)) T-REGULATORY (TREG) CELLS THAT NORMALLY SUPPRESS INFLAMMATORY EVENTS ARE OFTEN POORLY FUNCTIONING. METHODS: BASED ON OUR PREVIOUS PUBLISHED FINDINGS THAT METHYLATED DNA CPG (CYTOSINE [C], PHOSPHATE [P], GUANINE [G]) OLIGONUCLEOTIDE (ODN) BUT NOT UNMETHYLATED CPG ODN SEQUENCE WAS SHOWN TO PROMOTE FOXP3 EXPRESSION IN HUMAN CD4(+) T CELLS, THE ARTICLE REVIEWED THE APPLICATION OF DNA METHYLATION AND TREG INDUCTION TO CANCER, AUTOIMMUNE DISEASES, AND THE ALLERGIC DISORDERS. RESULTS: THE CENTRAL UNIFYING THEME OF DNA METHYLATION EPIGENETIC MECHANISM IS ITS COMPARATIVE DESCRIPTION TO AN ELECTRONIC "SWITCH," WHICH, WHEN IN THE METHYLATED STATE FUNCTIONS IN THE "CLOSED" POSITION WITH GENE SILENCING, GENOME STABILITY, AND DECREASED GENE EXPRESSION, WHEREAS DNA HYPOMETHYLATION IS ANALOGOUS TO THE "OPENED" POSITION OF THE SWITCH, WHICH LEADS TO ACTIVE TRANSCRIPTION AND INCREASED GENE EXPRESSION. CONCLUSION: OF THE THREE EPIGENETIC MECHANISMS THAT INCLUDE DNA METHYLATION, COVALENT POSTTRANSLATIONAL HISTONE MODIFICATIONS, AND MICRO-RNA-MEDIATED GENE SILENCING, DNA METHYLATION PLAYS THE MAJOR ROLE IN UNDERSTANDING MECHANISMS INVOLVED IN ALLERGY AND IMMUNOTHERAPY. EPIGENETICS HOLDS THE KEY TO UNRAVELING THE COMPLEX ASSOCIATIONS BETWEEN DISEASE PHENOTYPES AND ENDOTYPES, IDENTIFYING SAFER AND EFFECTIVE THERAPIES, AND CREATING A BETTER DIAGNOSIS AND TREATMENT OF ALLERGIC DISEASES. GENETICS LOADS THE GUN AND EPIGENETICS PULLS THE TRIGGER. 2019 18 3418 21 HUMAN HEALTH CONSEQUENCES OF ENVIRONMENTALLY-MODULATED GENE EXPRESSION: POTENTIAL ROLES OF ELF-EMF INDUCED EPIGENETIC VERSUS MUTAGENIC MECHANISMS OF DISEASE. IN ORDER TO DETERMINE IF THERE MIGHT BE BIOLOGICAL AND HEALTH CONSEQUENCES AFTER EXPOSURES TO EXTREMELY-LOW FREQUENCY ELECTROMAGNETIC FIELDS (ELF-EMF), EITHER EXPERIMENTALLY OR EPIDEMIOLOGICALLY, MECHANISTIC UNDERSTANDING OF THE POTENTIAL MEANS BY WHICH ANY ENVIRONMENTAL AGENT CAN AFFECT CELLS IN A MULTICELLULAR ORGANISM HAS TO BE REVIEWED. THE GOAL OF THIS LIMITED REVIEW IS TO DEMONSTRATE THAT, WHILE THE PREVAILING PARADIGM OF THE ENVIRONMENTALLY-INDUCED ACUTE AND CHRONIC DISEASES INVOLVES EITHER CELL KILLING (CYTOTOXICITY) OR GENE/CHROMOSOME MUTATIONS (GENOTOXICITY), ALTERATION OF THE EXPRESSION OF GENETIC INFORMATION AT THE TRANSCRIPTIONAL (TURNING GENES "ON" OR "OFF"), TRANSLATIONAL (STABILIZING OR DE-STABILIZING THE GENETIC MESSAGE), OR POSTTRANSLATIONAL (ALTERING THE GENE PRODUCT OR PROTEIN) LEVELS HAS THE POTENTIAL TO CONTRIBUTE TO VARIOUS DISEASES. THIS LATTER MECHANISM, "EPIGENETIC" TOXICITY, UNLIKE THE FORMER TWO WHICH ARE IRREVERSIBLE, IS CHARACTERIZED BY THRESHOLD-LIKE ACTION, MULTIPLE BIOCHEMICAL PATHWAYS AND CHRONIC, REGULAR EXPOSURES TO BE EFFECTIVE. ULTIMATELY, EPIGENETIC TOXICANTS AFFECT ONE OF FOUR POTENTIAL CELL STATES, NAMELY ALTERATION OF CELL PROLIFERATION, CELL DIFFERENTIATION, PROGRAMMED CELL DEATH (APOPTOSIS) OR ADAPTIVE RESPONSES OF DIFFERENTIATED CELLS. 2000 19 2138 26 EPIGENETIC INHERITANCE OF FETAL GENES IN ALLERGIC ASTHMA. ASTHMA HAS BEEN ASSOCIATED WITH AN EXAGGERATED T-HELPER TYPE 2 (TH2) OVER TH1 RESPONSES TO ALLERGIC AND NONALLERGIC STIMULI, WHICH LEADS TO CHRONIC AIRWAY INFLAMMATION AND AIRWAY REMODELING. IN THE PRESENT ARTICLE, WE PROPOSE THAT MANY OF THE GENES INVOLVED IN IGE SYNTHESIS AND AIRWAYS (RE)MODELING IN ASTHMA ARE PERSISTENT OR REMINISCENT FETAL GENES WHICH MAY NOT BE SILENCED DURING EARLY INFANCY (OR LATE PREGNANCY). GENES OF THE EMBRYOLOGIC DIFFERENTIATION OF ECTODERMIC AND ENDODERMIC TISSUES MAY EXPLAIN SOME OF THE PATTERNS OF AIRWAY REMODELING IN ASTHMA. IN UTERO PROGRAMMING LEADS TO GENE EXPRESSION, THE PERSISTENCE OF WHICH MAY BE ASSOCIATED WITH EPIGENETIC INHERITANCE PHENOMENA INDUCED BY NONSPECIFIC ENVIRONMENTAL FACTORS. CLEAR DELINEATION OF THESE ISSUES MAY YIELD NEW INFORMATION ON THE MECHANISMS OF ASTHMA AND NEW TARGETS FOR THERAPEUTIC INTERVENTION AND PRIMARY PREVENTION. 2004 20 2290 30 EPIGENETIC REGULATION IN MURINE OFFSPRING AS A NOVEL MECHANISM FOR TRANSMATERNAL ASTHMA PROTECTION INDUCED BY MICROBES. BACKGROUND: BRONCHIAL ASTHMA IS A CHRONIC INFLAMMATORY DISEASE RESULTING FROM COMPLEX GENE-ENVIRONMENT INTERACTIONS. NATURAL MICROBIAL EXPOSURE HAS BEEN IDENTIFIED AS AN IMPORTANT ENVIRONMENTAL CONDITION THAT PROVIDES ASTHMA PROTECTION IN A PRENATAL WINDOW OF OPPORTUNITY. EPIGENETIC REGULATION IS AN IMPORTANT MECHANISM BY WHICH ENVIRONMENTAL FACTORS MIGHT INTERACT WITH GENES INVOLVED IN ALLERGY AND ASTHMA DEVELOPMENT. OBJECTIVE: THIS STUDY WAS DESIGNED TO TEST WHETHER EPIGENETIC MECHANISMS MIGHT CONTRIBUTE TO ASTHMA PROTECTION CONFERRED BY EARLY MICROBIAL EXPOSURE. METHODS: PREGNANT MATERNAL MICE WERE EXPOSED TO THE FARM-DERIVED GRAM-NEGATIVE BACTERIUM ACINETOBACTER LWOFFII F78. EPIGENETIC MODIFICATIONS IN THE OFFSPRING WERE ANALYZED IN T(H)1- AND T(H)2-RELEVANT GENES OF CD4(+) T CELLS. RESULTS: PRENATAL ADMINISTRATION OF A LWOFFII F78 PREVENTED THE DEVELOPMENT OF AN ASTHMATIC PHENOTYPE IN THE PROGENY, AND THIS EFFECT WAS IFN-GAMMA DEPENDENT. FURTHERMORE, THE IFNG PROMOTER OF CD4(+) T CELLS IN THE OFFSPRING REVEALED A SIGNIFICANT PROTECTION AGAINST LOSS OF HISTONE 4 (H4) ACETYLATION, WHICH WAS CLOSELY ASSOCIATED WITH IFN-GAMMA EXPRESSION. PHARMACOLOGIC INHIBITION OF H4 ACETYLATION IN THE OFFSPRING ABOLISHED THE ASTHMA-PROTECTIVE PHENOTYPE. REGARDING T(H)2-RELEVANT GENES ONLY AT THE IL4 PROMOTER, A DECREASE COULD BE DETECTED FOR H4 ACETYLATION BUT NOT AT THE IL5 PROMOTER OR THE INTERGENIC T(H)2 REGULATORY REGION CONSERVED NONCODING SEQUENCE 1 (CNS1). CONCLUSION: THESE DATA SUPPORT THE HYGIENE CONCEPT AND INDICATE THAT MICROBES OPERATE BY MEANS OF EPIGENETIC MECHANISMS. THIS PROVIDES A NEW MECHANISM IN THE UNDERSTANDING OF GENE-ENVIRONMENT INTERACTIONS IN THE CONTEXT OF ALLERGY PROTECTION. 2011