1 3410 162 HOXA5 UNDERGOES DYNAMIC DNA METHYLATION AND TRANSCRIPTIONAL REPRESSION IN THE ADIPOSE TISSUE OF MICE EXPOSED TO HIGH-FAT DIET. BACKGROUND/OBJECTIVES: THE GENOMIC BASES OF THE ADIPOSE TISSUE ABNORMALITIES INDUCED BY CHRONIC POSITIVE CALORIE EXCESS HAVE BEEN ONLY PARTIALLY ELUCIDATED. WE ADOPTED A GENOME-WIDE APPROACH TO DIRECTLY TEST WHETHER LONG-TERM HIGH-FAT DIET (HFD) EXPOSURE AFFECTS THE DNA METHYLATION PROFILE OF THE MOUSE ADIPOSE TISSUE AND TO IDENTIFY THE FUNCTIONAL CONSEQUENCES OF THESE CHANGES. SUBJECTS/METHODS: WE HAVE USED EPIDIDYMAL FAT OF MICE FED EITHER HIGH-FAT (HFD) OR REGULAR CHOW (STD) DIET FOR 5 MONTHS AND PERFORMED GENOME-WIDE DNA METHYLATION ANALYSES BY METHYLATED DNA IMMUNOPRECIPITATION SEQUENCING (MEDIP-SEQ). MOUSE HOMEOBOX (HOX) GENE DNA METHYLATION PCR, RT-QPCR AND BISULPHITE SEQUENCING ANALYSES WERE THEN PERFORMED. RESULTS: MICE FED THE HFD PROGRESSIVELY EXPANDED THEIR ADIPOSE MASS ACCOMPANIED BY A SIGNIFICANT DECREASE IN GLUCOSE TOLERANCE (P<0.001) AND INSULIN SENSITIVITY (P<0.05). MEDIP-SEQ DATA ANALYSIS REVEALED A UNIFORM DISTRIBUTION OF DIFFERENTIALLY METHYLATED REGIONS (DMR) THROUGH THE ENTIRE ADIPOCYTE GENOME, WITH A HIGHER NUMBER OF HYPERMETHYLATED REGIONS IN HFD MICE (P<0.005). THIS DIFFERENT METHYLATION PROFILE WAS ACCOMPANIED BY INCREASED EXPRESSION OF THE DNMT3A DNA METHYLTRANSFERASE (DNMT; P<0.05) AND THE METHYL-CPG-BINDING DOMAIN PROTEIN MBD3 (P<0.05) GENES IN HFD MICE. GENE ONTOLOGY ANALYSIS REVEALED THAT, IN THE HFD-TREATED MICE, THE HOX FAMILY OF DEVELOPMENT GENES WAS HIGHLY ENRICHED IN DIFFERENTIALLY METHYLATED GENES (P=0.008). TO VALIDATE THIS FINDING, HOXA5, WHICH IS IMPLICATED IN FAT TISSUE DIFFERENTIATION AND REMODELING, HAS BEEN SELECTED AND ANALYZED BY BISULPHITE SEQUENCING, CONFIRMING HYPERMETHYLATION IN THE ADIPOSE TISSUE FROM THE HFD MICE. HOXA5 HYPERMETHYLATION WAS ASSOCIATED WITH DOWNREGULATION OF HOXA5 MRNA AND PROTEIN EXPRESSION. FEEDING ANIMALS PREVIOUSLY EXPOSED TO THE HFD WITH A STANDARD CHOW DIET FOR TWO FURTHER MONTHS IMPROVED THE METABOLIC PHENOTYPE OF THE ANIMALS, ACCOMPANIED BY RETURN OF HOXA5 METHYLATION AND EXPRESSION LEVELS (P<0.05) TO VALUES SIMILAR TO THOSE OF THE CONTROL MICE MAINTAINED UNDER STANDARD CHOW. CONCLUSIONS: HFD INDUCES ADIPOSE TISSUE ABNORMALITIES ACCOMPANIED BY EPIGENETIC CHANGES AT THE HOXA5 ADIPOSE TISSUE REMODELING GENE. 2016 2 3 49 "EPIGENOME-WIDE METHYLATION PROFILE OF CHRONIC KIDNEY DISEASE-DERIVED ARTERIAL DNA UNCOVERS NOVEL PATHWAYS IN DISEASE-ASSOCIATED CARDIOVASCULAR PATHOLOGY.". CHRONIC KIDNEY DISEASE (CKD) RELATED CARDIOVASCULAR DISEASE (CVD) IS CHARACTERIZED BY VASCULAR REMODELLING WITH WELL-ESTABLISHED STRUCTURAL AND FUNCTIONAL CHANGES IN THE VASCULAR WALL SUCH AS ARTERIAL STIFFNESS, MATRIX DEPOSITION, AND CALCIFICATION. THESE PHENOTYPIC CHANGES RESEMBLE PATHOLOGY SEEN IN AGEING, AND ARE LIKELY TO BE MEDIATED BY SUSTAINED ALTERATIONS IN GENE EXPRESSION, WHICH MAY BE CAUSED BY EPIGENETIC CHANGES SUCH AS TISSUE-SPECIFIC DNA METHYLATION. WE AIMED TO INVESTIGATE TISSUE SPECIFIC CHANGES IN DNA METHYLATION THAT OCCUR IN CKD-RELATED CVD. GENOME-WIDE DNA METHYLATION CHANGES WERE EXAMINED IN BISULPHITE CONVERTED GENOMIC DNA ISOLATED FROM THE VASCULAR MEDIA OF CKD AND HEALTHY ARTERIES. METHYLATION-SPECIFIC PCR WAS USED TO VALIDATE THE ARRAY DATA, AND THE ASSOCIATION BETWEEN DNA METHYLATION AND GENE AND PROTEIN EXPRESSION WAS EXAMINED. THE DNA METHYLATION AGE WAS COMPARED TO THE CHRONOLOGICAL AGE IN BOTH CASES AND CONTROLS. THREE HUNDRED AND NINETEEN DIFFERENTIALLY METHYLATED REGIONS (DMR) WERE IDENTIFIED SPREAD ACROSS THE GENOME. PATHWAY ANALYSIS REVEALED THAT DMRS ASSOCIATED WITH GENES WERE INVOLVED IN EMBRYONIC AND VASCULAR DEVELOPMENT, AND SIGNALLING PATHWAYS SUCH AS TGFBETA AND FGF. EXPRESSION OF TOP DIFFERENTIALLY METHYLATED GENE HOXA5 SHOWED A SIGNIFICANT NEGATIVE CORRELATION WITH DNA METHYLATION. INTERESTINGLY, DNA METHYLATION AGE AND CHRONOLOGICAL AGE WERE HIGHLY CORRELATED, BUT THERE WAS NO EVIDENCE OF ACCELERATED AGE-RELATED DNA METHYLATION IN THE ARTERIES OF CKD PATIENTS. IN CONCLUSION, WE DEMONSTRATED THAT DIFFERENTIAL DNA METHYLATION IN THE ARTERIAL TISSUE OF CKD PATIENTS REPRESENTS A POTENTIAL MEDIATOR OF ARTERIAL PATHOLOGY AND MAY BE USED TO UNCOVER NOVEL PATHWAYS IN THE GENESIS OF CKD-ASSOCIATED COMPLICATIONS. 2021 3 2400 41 EPIGENETIC REPROGRAMMING OF IMMUNE CELLS IN WOMEN WITH PCOS IMPACT GENES CONTROLLING REPRODUCTIVE FUNCTION. CONTEXT: POLYCYSTIC OVARY SYNDROME (PCOS) IS A CHRONIC DISEASE AFFECTING REPRODUCTIVE FUNCTION AND WHOLE-BODY METABOLISM. ALTHOUGH THE ETIOLOGY IS UNCLEAR, EMERGING EVIDENCE INDICATES THAT THE EPIGENETICS MAY BE A CONTRIBUTING FACTOR. OBJECTIVE: TO DETERMINE THE ROLE OF GLOBAL AND GENOME-WIDE EPIGENETIC MODIFICATIONS IN SPECIFIC IMMUNE CELLS IN PCOS COMPARED WITH CONTROLS AND WHETHER THESE COULD BE RELATED TO CLINICAL FEATURES OF PCOS. DESIGN: CROSS-SECTIONAL STUDY. PARTICIPANTS: WOMEN WITH (N = 17) OR WITHOUT PCOS (N = 17). SETTING: RECRUITED FROM THE GENERAL COMMUNITY. MAIN OUTCOME MEASURES: ISOLATED PERIPHERAL BLOOD MONONUCLEAR CELLS WERE ANALYZED USING MULTICOLOR FLOW CYTOMETRY METHODS TO DETERMINE GLOBAL DNA METHYLATION LEVELS IN A CELL-SPECIFIC FASHION. TRANSCRIPTOMIC AND GENOME-WIDE DNA METHYLATION ANALYSES WERE PERFORMED ON T HELPER CELLS USING RNA SEQUENCING AND REDUCED REPRESENTATION BISULFITE SEQUENCING. RESULTS: WOMEN WITH PCOS HAD LOWER GLOBAL DNA METHYLATION IN MONOCYTES (P = 0.006) AND IN T HELPER (P = 0.004), T CYTOTOXIC (P = 0.004), AND B CELLS (P = 0.03). SPECIFIC GENOME-WIDE DNA METHYLATION ANALYSIS OF T HELPER CELLS FROM WOMEN WITH PCOS IDENTIFIED 5581 DIFFERENTIALLY METHYLATED CPG SITES. FUNCTIONAL GENE ONTOLOGY ENRICHMENT ANALYSIS SHOWED THAT GENES LOCATED AT THE PROXIMITY OF DIFFERENTIALLY METHYLATED CPG SITES BELONG TO PATHWAYS RELATED TO REPRODUCTIVE FUNCTION AND IMMUNE CELL FUNCTION. HOWEVER, THESE GENES WERE NOT ALTERED AT THE TRANSCRIPTOMIC LEVEL. CONCLUSIONS: IT WAS SHOWN THAT PCOS IS ASSOCIATED WITH GLOBAL AND GENE-SPECIFIC DNA METHYLATION REMODELING IN A CELL TYPE-SPECIFIC MANNER. FURTHER INVESTIGATION IS WARRANTED TO DETERMINE WHETHER EPIGENETIC REPROGRAMMING OF IMMUNE CELLS IS IMPORTANT IN DETERMINING THE DIFFERENT PHENOTYPES OF PCOS. 2019 4 1795 44 EFFECT OF DIFFERENT COMBINATION OF MATERNAL AND POSTNATAL DIET ON ADIPOSE TISSUE MORPHOLOGY IN MALE RAT OFFSPRING. PURPOSE: ADIPOSE TISSUE EXPANSION CAN OCCUR THROUGH SEVERAL DIFFERENT WAYS AND, UNDER CERTAIN CONDITIONS, CAN BE CONNECTED WITH CHRONIC INFLAMMATION. TNF-ALPHA IS ONE OF THE IMPORTANT CYTOKINES INVOLVED IN THIS PROCESS. PROLONGED INFLAMMATION IN OBESITY CAN LEAD TO OBESITY-RELATED INSULIN RESISTANCE AND TISSUE DYSFUNCTION. THE AIM OF OUR STUDY WAS TO INVESTIGATE HOW DIFFERENT COMBINATION OF MATERNAL AND POSTNATAL DIET AFFECTS OFFSPRING ADIPOSE TISSUE MORPHOLOGY AND ADIPOSE TISSUE TNF-ALPHA EXPRESSION. METHODS: TEN FEMALE SPRAGUE DAWLEY RATS, 9 WEEKS OLD, WERE RANDOMLY DIVIDED INTO TWO GROUPS AND FED EITHER STANDARD LABORATORY CHOW OR FOOD RICH IN SATURATED FATTY ACIDS DURING 6 WEEKS AND THEN MATED WITH THE SAME MALE RAT. AFTER BIRTH AND LACTATION MALE RAT OFFSPRING FROM BOTH GROUPS WERE DIVIDED INTO FOUR SUBGROUPS DEPENDING ON THE DIET THEY WERE FED UNTIL 22 WEEKS OLD. SAMPLES OF WHITE ADIPOSE TISSUE WERE TAKEN FROM THE SUBCUTANEOUS, EPIDIDYMAL, AND PERIRENAL FAT PAD. ON TISSUE SECTIONS, HISTOMORPHOMETRIC ANALYSIS WAS CONDUCTED USING CELLPROFILER PROGRAM V 2.1.1, AND IMMUNOHISTOCHEMICAL STAINING FOR TNF-ALPHA WAS PERFORMED. RESULTS: GREATER MEAN SURFACE AREA OF SUBCUTANEOUS AND EPIDIDYMAL ADIPOCYTES WAS FOUND IN GROUPS OF MALE RAT OFFSPRING WITH ALTERED DIET. IN PERIRENAL ADIPOSE TISSUE, THE HIGHEST NUMBER OF ADIPOCYTES WAS MEASURED IN THE GROUP WHERE BOTH MOTHER AND OFFSPRING WERE FED A HIGH-FAT DIET. ADIPOCYTE STAINING INTENSITY FOR TNF-ALPHA DID NOT DIFFER SIGNIFICANTLY BETWEEN THE GROUPS. CONCLUSIONS: TOGETHER WITH OUR PREVIOUSLY PUBLISHED DATA, OUR RESULTS LEAD TO THE CONCLUSION THAT ALTERATION OF POSTNATAL DIET CAN LEAD TO TNF-ALPHA AND ADIPOCYTE MORPHOLOGY CHANGES. 2019 5 1589 49 DNA METHYLATION PROFILING IN A CIGARETTE SMOKE-EXPOSED MOUSE MODEL OF AIRWAY INFLAMMATION. PURPOSE: DNA METHYLATION, A MAJOR EPIGENETIC MODIFICATION, HAS BEEN DOCUMENTED TO PLAY AN IMPORTANT ROLE IN CHRONIC OBSTRUCTIVE PULMONARY DISEASE (COPD). IN THIS STUDY, WE AIMED TO PROFILE THE DNA METHYLATION PATTERNS IN A MOUSE MODEL OF AIRWAY INFLAMMATION INDUCED BY CIGARETTE SMOKE (CS), A FOREMOST RISK FACTOR OF COPD. MATERIAL AND METHODS: TO ESTABLISH A MODEL OF AIRWAY INFLAMMATION, WILD-TYPE MICE WERE EXPOSED TO MAINSTREAM CS OR ROOM AIR FOR 2 HOURS TWICE DAILY, 6 DAYS PER WEEK FOR CONSECUTIVE 4 WEEKS. LUNG TISSUES OF THE MICE WERE COLLECTED FOR GENOME-WIDE DNA METHYLATION ANALYSIS BY LIQUID HYBRIDIZATION CAPTURE-BASED BISULFITE SEQUENCING, WHICH WERE USED FOR INTERSECTION ANALYSIS WITH GENE EXPRESSION BY CDNA MICROARRAY TO IDENTIFY CANDIDATE METHYLATED GENES. THEN, FUNCTIONAL ENRICHMENT ANALYSES WITH PROTEIN-PROTEIN INTERACTION (PPI) NETWORK REGARDING THESE GENES WERE CONDUCTED TO EXPLORE THE POTENTIAL MECHANISMS. RESULTS: AFTER 4-WEEK CS EXPOSURE, THE LEVEL OF DNA METHYLATION ACCOMPANIED BY A SUBACUTE AIRWAY INFLAMMATION WAS MARKEDLY ENHANCED, AND 2002 DIFFERENTIALLY METHYLATED GENES (DMGS) WERE ANNOTATED, INCLUDING 565 DMGS CONTAINED METHYLATIONS IN GENE PROMOTERS, WHICH WERE USED FOR INTERSECTION WITH THE DIFFERENTIALLY EXPRESSED GENES. THEN, 135 CANDIDATE METHYLATED GENES WERE FURTHER SELECTED BY THE INTERSECTION, AMONG WHICH 58 GENES WITH FUNCTIONAL METHYLATED MODIFICATION WERE FINALLY IDENTIFIED. FURTHER ANALYSES REVEALED CANDIDATE METHYLATED GENES WERE SIGNIFICANTLY ENRICHED IN A COMPLICATED NETWORK OF SIGNALS AND PROCESSES, INCLUDING INTERLEUKINS, TOLL-LIKE RECEPTORS, T-CELLS DIFFERENTIATION, OXIDATIVE STRESS, MAST CELLS ACTIVATION, STEM CELLS PROLIFERATION, ETC., AS WELL AS THE 58 FUNCTIONAL METHYLATED GENES WERE PARTIALLY LOCATED AT KEY POSITIONS IN PPI NETWORK, ESPECIALLY CXCL1, DDX58 AND JAK3. CONCLUSION: THIS STUDY SUGGESTS CS EXPOSURE SIGNIFICANTLY ENHANCES DNA METHYLATED LEVEL, AND THE POTENTIAL FUNCTIONAL METHYLATED GENES ARE CLOSELY RELATED TO COMPLICATED INFLAMMATORY-IMMUNE RESPONSES, WHICH MAY PROVIDE SOME NEW EXPERIMENTAL EVIDENCE IN UNDERSTANDING THE EPIGENETIC MECHANISMS OF CS-INDUCED AIRWAY INFLAMMATION IN COPD. 2022 6 1500 44 DNA METHYLATION ANALYSIS OF CD4+ T CELLS IN PATIENTS WITH PSORIASIS. PSORIASIS IS A CHRONIC INFLAMMATORY SKIN DISEASE THAT IS CHARACTERIZED BY ABERRANT CROSS-TALK BETWEEN KERATINOCYTES AND IMMUNE CELLS SUCH AS CD4+ T CELLS, RESULTING IN KERATINOCYTE HYPERPROLIFERATION IN THE EPIDERMIS. DNA METHYLATION, ONE OF SEVERAL EPIGENETIC MECHANISMS, PLAYS AN IMPORTANT ROLE IN GENE EXPRESSION WITHOUT CHANGING THE DNA SEQUENCE. SEVERAL STUDIES HAVE SUGGESTED THE INVOLVEMENT OF EPIGENETIC REGULATION IN SKIN LESIONS FROM PATIENTS WITH PSORIASIS. IN THIS STUDY, WE INVESTIGATED THE GENOME-WIDE DNA METHYLATION STATUS OF CD4+ T CELLS IN PATIENTS WITH PSORIASIS COMPARED WITH HEALTHY SUBJECTS USING METHYLATED DNA IMMUNOPRECIPITATION SEQUENCING (MEDIP-SEQ). THE RESULTS OF MEDIP-SEQ SHOWED THAT THE GLOBAL METHYLATION VALUES OF CD4+ T CELLS ARE HIGHER IN PATIENTS WITH PSORIASIS THAN IN HEALTHY CONTROLS, PARTICULARLY IN THE PROMOTER REGIONS. AMONG THE MOST HYPERMETHYLATED GENES IN THE PROMOTER REGIONS, WE SELECTED THE GENES WHOSE EXPRESSION IS SIGNIFICANTLY REDUCED IN THE CD4+ T CELLS OF PSORIASIS PATIENTS. STUDIES USING THE METHYLATION INHIBITOR 5-AZACYTIDINE IN VITRO METHYLATION ASSAYS HAVE SHOWN THAT THE DIFFERENTIAL EXPRESSION LEVELS WERE ASSOCIATED WITH THE METHYLATION STATUS OF EACH GENE. BISULFITE SEQUENCING OF THE TRANSCRIPTION START REGION OF PHOSPHATIDIC ACID PHOSPHATASE TYPE 2 DOMAIN CONTAINING 3 (PPAPDC3), ONE OF THE SELECTED GENES, SHOWED HYPERMETHYLATION IN THE CD4+ T CELLS OF PSORIASIS PATIENTS. THESE RESULTS SUGGESTED THAT THE METHYLATION STATUS, WHICH IS IDENTIFIED BY MEDIP-SEQ OF THE GENES, WAS CORRELATED WITH THE MRNA EXPRESSION LEVEL OF THE GENES. COLLECTIVELY, THE DNA METHYLATION STATUS IN CD4+ T CELLS MIGHT BE ASSOCIATED WITH THE PATHOGENESIS OF PSORIASIS. 2014 7 990 43 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 8 1583 35 DNA METHYLATION PROFILES OF BLOOD CELLS ARE DISTINCT BETWEEN EARLY-ONSET OBESE AND CONTROL INDIVIDUALS. OBESITY IS A HIGHLY PREVALENT, CHRONIC DISORDER THAT HAS BEEN INCREASING IN INCIDENCE IN YOUNG PATIENTS. BOTH EPIGENETIC AND GENETIC ABERRATIONS MAY PLAY A ROLE IN THE PATHOGENESIS OF OBESITY. THEREFORE, IN-DEPTH EPIGENOMIC AND GENOMIC ANALYSES WILL ADVANCE OUR UNDERSTANDING OF THE DETAILED MOLECULAR MECHANISMS UNDERLYING OBESITY AND AID IN THE SELECTION OF POTENTIAL BIOMARKERS FOR OBESITY IN YOUTH. HERE, WE PERFORMED MICROARRAY-BASED DNA METHYLATION AND GENE EXPRESSION PROFILING OF PERIPHERAL WHITE BLOOD CELLS OBTAINED FROM SIX YOUNG, OBESE INDIVIDUALS AND SIX HEALTHY CONTROLS. WE OBSERVED THAT THE HIERARCHICAL CLUSTERING OF DNA METHYLATION, BUT NOT GENE EXPRESSION, CLEARLY SEGREGATES THE OBESE INDIVIDUALS FROM THE CONTROLS, SUGGESTING THAT THE METABOLIC DISTURBANCE THAT OCCURS AS A RESULT OF OBESITY AT A YOUNG AGE MAY AFFECT THE DNA METHYLATION OF PERIPHERAL BLOOD CELLS WITHOUT ACCOMPANYING TRANSCRIPTIONAL CHANGES. TO EXAMINE THE GENOME-WIDE DIFFERENCES IN THE DNA METHYLATION PROFILES OF YOUNG OBESE AND CONTROL INDIVIDUALS, WE IDENTIFIED DIFFERENTIALLY METHYLATED CPG SITES AND INVESTIGATED THEIR GENOMIC AND EPIGENOMIC CONTEXTS. THE ABERRANT DNA METHYLATION PATTERNS IN OBESE INDIVIDUALS CAN BE SUMMARIZED AS RELATIVE GAINS AND LOSSES OF DNA METHYLATION IN GENE PROMOTERS AND GENE BODIES, RESPECTIVELY. WE ALSO OBSERVED THAT THE CPG ISLANDS OF OBESE INDIVIDUALS ARE MORE SUSCEPTIBLE TO DNA METHYLATION COMPARED TO CONTROLS. OUR PILOT STUDY SUGGESTS THAT THE GENOME-WIDE ABERRANT DNA METHYLATION PATTERNS OF OBESE INDIVIDUALS MAY ADVANCE NOT ONLY OUR UNDERSTANDING OF THE EPIGENOMIC PATHOGENESIS BUT ALSO EARLY SCREENING OF OBESITY IN YOUTH. 2017 9 1784 50 EFFECT OF ALCOHOL CONSUMPTION ON CPG METHYLATION IN THE DIFFERENTIALLY METHYLATED REGIONS OF H19 AND IG-DMR IN MALE GAMETES: IMPLICATIONS FOR FETAL ALCOHOL SPECTRUM DISORDERS. BACKGROUND: EXPOSURE TO ALCOHOL IN UTERO IS THE MAIN ATTRIBUTABLE CAUSE OF FETAL ALCOHOL SPECTRUM DISORDERS (FASD) WHICH IN ITS MOST SEVERE FORM IS CHARACTERIZED BY IRREVERSIBLE BEHAVIORAL AND COGNITIVE DISABILITY. PATERNAL PRECONCEPTION DRINKING IS NOT CONSIDERED TO BE A SIGNIFICANT RISK FACTOR, EVEN THOUGH ANIMAL STUDIES HAVE DEMONSTRATED THAT CHRONIC PATERNAL ALCOHOL CONSUMPTION HAS A DETRIMENTAL EFFECT ON THE PHYSICAL AND MENTAL DEVELOPMENT OF OFFSPRING EVEN IN THE ABSENCE OF IN UTERO ALCOHOL EXPOSURE. IT HAS BEEN DOCUMENTED THAT ALCOHOL CAN REDUCE THE LEVELS AND ACTIVITY OF DNA METHYLTRANSFERASES RESULTING IN DNA HYPOMETHYLATION AND THAT REDUCED METHYLTRANSFERASE ACTIVITY CAN CAUSE ACTIVATION OF NORMALLY SILENCED GENES. THE AIM OF THIS STUDY WAS TO ESTABLISH A LINK BETWEEN ALCOHOL USE IN MEN AND HYPOMETHYLATION OF PATERNALLY IMPRINTED LOCI IN SPERM DNA IN GENOMIC REGIONS CRITICAL FOR EMBRYONIC DEVELOPMENT, THUS PROVIDING A MECHANISM FOR PATERNAL EFFECTS IN THE AETIOLOGY OF FASD. METHODS: SPERM DNA FROM MALE VOLUNTEERS WAS BISULFITE TREATED AND THE METHYLATION PATTERNS OF 2 DIFFERENTIALLY METHYLATED REGIONS (DMRS), H19 AND IG-DMR, ANALYZED FOLLOWING SEQUENCING OF INDIVIDUAL CLONES. THE METHYLATION PATTERNS WERE CORRELATED WITH THE ALCOHOL CONSUMPTION LEVELS OF THE VOLUNTEER MALES. RESULTS: THERE WAS A PATTERN OF INCREASED DEMETHYLATION WITH ALCOHOL CONSUMPTION AT THE 2 IMPRINTED LOCI WITH A SIGNIFICANT DIFFERENCE OBSERVED AT THE IG-DMR BETWEEN THE NONDRINKING AND HEAVY ALCOHOL CONSUMING GROUPS. GREATER INTER-INDIVIDUAL VARIATION IN AVERAGE METHYLATION WAS OBSERVED AT THE H19 DMR AND INDIVIDUAL CLONES WERE MORE EXTENSIVELY DEMETHYLATED THAN THOSE OF THE IG-DMR. CPG SITE #4 IN THE IG-DMR WAS PREFERENTIALLY DEMETHYLATED AMONG ALL INDIVIDUALS AND ALONG WITH THE H19 DMR CPG SITE #7 LOCATED WITHIN THE CTCF BINDING SITE 6 SHOWED SIGNIFICANT DEMETHYLATION IN THE ALCOHOL CONSUMING GROUPS COMPARED WITH THE CONTROL GROUP. CONCLUSION: THIS STUDY DEMONSTRATES A CORRELATION BETWEEN CHRONIC ALCOHOL USE AND DEMETHYLATION OF NORMALLY HYPERMETHYLATED IMPRINTED REGIONS IN SPERM DNA. WE HYPOTHESIZE THAT, SHOULD THESE EPIGENETIC CHANGES IN IMPRINTED GENES BE TRANSMITTED THROUGH FERTILIZATION, THEY WOULD ALTER THE CRITICAL GENE EXPRESSION DOSAGES REQUIRED FOR NORMAL PRENATAL DEVELOPMENT RESULTING IN OFFSPRING WITH FEATURES OF FASD. 2009 10 894 40 CHRONIC ETHANOL FEEDING ALTERS HEPATOCYTE MEMORY WHICH IS NOT ALTERED BY ACUTE FEEDING. BACKGROUND: GENE EXPRESSION CHANGES IN THE LIVER AFTER ACUTE BINGE DRINKING MAY DIFFER FROM THE CHANGES SEEN IN CHRONIC ETHANOL FEEDING IN THE RAT. THE CHANGES IN GENE EXPRESSION AFTER CHRONIC ETHANOL FEEDING MAY SENSITIZE THE LIVER TO ALCOHOL-INDUCED LIVER DAMAGE, WHICH IS NOT SEEN AFTER ACUTE BINGE DRINKING. METHODS: TO TEST THIS HYPOTHESIS, GENE MICROARRAY ANALYSIS WAS PERFORMED ON THE LIVERS OF RATS (N = 3) FED AN ACUTE BINGE DOSE OF ETHANOL (6 G/KG BODY WT) AND KILLED AT 3 AND 12 HOURS AFTER ETHANOL BY GAVAGE. THE GENE MICROARRAYS WERE COMPARED WITH THOSE MADE ON THE LIVER OF RATS FROM A PREVIOUS STUDY, IN WHICH THE RATS WERE FED ETHANOL BY INTRAGASTRIC TUBE FOR 1 MONTH (36% OF CALORIES DERIVED FROM ETHANOL). RESULTS: MICROARRAY ANALYSIS DATA VARIED BETWEEN THE ACUTE AND CHRONIC MODELS IN SEVERAL IMPORTANT RESPECTS. GROWTH FACTORS INCREASED MAINLY IN THE CHRONIC ALCOHOL FED RAT. CHANGES IN ENZYMES INVOLVED IN OXIDATIVE STRESS WERE NOTED ONLY WITH CHRONIC ETHANOL FEEDING. GENE EXPRESSION OF FAT METABOLISM WAS INCREASED ONLY WITH CHRONIC ETHANOL FEEDING. MOST IMPORTANTLY, EPIGENETIC RELATED ENZYMES AND ACETYLATION AND METHYLATION OF HISTONES CHANGED ONLY AFTER CHRONIC ETHANOL FEEDING. CONCLUSIONS: THE RESULTS SUPPORT THE CONCEPT THAT CHRONIC ETHANOL INGESTION INDUCES ALTERED GENE EXPRESSION AS A RESULT OF CHANGES IN EPIGENETIC MECHANISMS, WHERE ACETYLATION AND METHYLATION OF HISTONES WERE ALTERED. 2009 11 3836 40 IONIZING RADIATION POTENTIATES HIGH-FAT DIET-INDUCED INSULIN RESISTANCE AND REPROGRAMS SKELETAL MUSCLE AND ADIPOSE PROGENITOR CELLS. EXPOSURE TO IONIZING RADIATION INCREASES THE RISK OF CHRONIC METABOLIC DISORDERS SUCH AS INSULIN RESISTANCE AND TYPE 2 DIABETES LATER IN LIFE. WE HYPOTHESIZED THAT IRRADIATION REPROGRAMS THE EPIGENOME OF METABOLIC PROGENITOR CELLS, WHICH COULD ACCOUNT FOR IMPAIRED METABOLISM AFTER CANCER TREATMENT. C57BL/6 MICE WERE TREATED WITH A SINGLE DOSE OF IRRADIATION AND SUBJECTED TO HIGH-FAT DIET (HFD). RNA SEQUENCING AND REDUCED REPRESENTATION BISULFITE SEQUENCING WERE USED TO CREATE TRANSCRIPTOMIC AND EPIGENOMIC PROFILES OF PREADIPOCYTES AND SKELETAL MUSCLE SATELLITE CELLS COLLECTED FROM IRRADIATED MICE. MICE SUBJECTED TO TOTAL BODY IRRADIATION SHOWED ALTERATIONS IN GLUCOSE METABOLISM AND, WHEN CHALLENGED WITH HFD, MARKED HYPERINSULINEMIA. INSULIN SIGNALING WAS CHRONICALLY DISRUPTED IN SKELETAL MUSCLE AND ADIPOSE PROGENITOR CELLS COLLECTED FROM IRRADIATED MICE AND DIFFERENTIATED IN CULTURE. EPIGENOMIC PROFILING OF SKELETAL MUSCLE AND ADIPOSE PROGENITOR CELLS FROM IRRADIATED ANIMALS REVEALED SUBSTANTIAL DNA METHYLATION CHANGES, NOTABLY FOR GENES REGULATING THE CELL CYCLE, GLUCOSE/LIPID METABOLISM, AND EXPRESSION OF EPIGENETIC MODIFIERS. OUR RESULTS SHOW THAT TOTAL BODY IRRADIATION ALTERS INTRACELLULAR SIGNALING AND EPIGENETIC PATHWAYS REGULATING CELL PROLIFERATION AND DIFFERENTIATION OF SKELETAL MUSCLE AND ADIPOSE PROGENITOR CELLS AND PROVIDE A POSSIBLE MECHANISM BY WHICH IRRADIATION USED IN CANCER TREATMENT INCREASES THE RISK FOR METABOLIC DISEASE LATER IN LIFE. 2016 12 1794 35 EFFECT OF DIABETES STATUS AND HYPERGLYCEMIA ON GLOBAL DNA METHYLATION AND HYDROXYMETHYLATION. TYPE 2 DIABETES MELLITUS (T2DM) IS CHARACTERIZED BY OXIDATIVE STRESS THAT COULD LEAD TO CHRONIC MICRO- AND MACROVASCULAR COMPLICATIONS. WE HYPOTHESIZED THAT SOME OF THE TARGET ORGAN DAMAGE IS MEDIATED BY OXIDATIVE ALTERATIONS IN EPIGENETIC MECHANISMS INVOLVING DNA METHYLATION (5MC) AND DNA HYDROXYMETHYLATION (5HMC). WE ANALYZED GLOBAL DNA METHYLATION AND HYDROXYMETHYLATION IN PERIPHERAL BLOOD CELLS IN WELL-CONTROLLED AND POORLY CONTROLLED PATIENTS WITH T2DM AND COMPARED THEM WITH HEALTHY CONTROLS. WE ALSO ANALYZED MICROARRAYS OF DNA METHYLATION AND GENE EXPRESSION OF OTHER IMPORTANT TISSUES IN THE CONTEXT OF DIABETES FROM THE GEO DATABASE REPOSITORY AND THEN COMPARED THESE RESULTS WITH OUR EXPERIMENTAL GENE EXPRESSION DATA. DNA METHYLATION AND, MORE IMPORTANTLY, DNA HYDROXYMETHYLATION LEVELS WERE INCREASED IN POORLY CONTROLLED PATIENTS COMPARED TO WELL-CONTROLLED AND HEALTHY INDIVIDUALS. BOTH 5MC AND 5HMC MEASUREMENTS WERE CORRELATED WITH THE PERCENTAGE OF GLYCATED HEMOGLOBIN, INDICATING A DIRECT IMPACT OF HYPERGLYCEMIA ON CHANGES OVER THE EPIGENOME. THE ANALYSIS OF METHYLATION MICROARRAYS WAS CONCORDANT, AND 5MC LEVELS WERE INCREASED IN THE PERIPHERAL BLOOD OF T2DM PATIENTS. HOWEVER, THE DNA METHYLATION LEVELS WERE THE OPPOSITE OF THOSE IN OTHER TISSUES, SUCH AS THE PANCREAS, ADIPOSE TISSUE AND SKELETAL MUSCLE. WE HYPOTHESIZE THAT A PROCESS OF DNA OXIDATION ASSOCIATED WITH HYPERGLYCEMIA MAY EXPLAIN THE DNA DEMETHYLATION IN WHICH THE ACTIVITY OF TEN-ELEVEN TRANSLOCATION (TET) PROTEINS IS NOT SUFFICIENT TO COMPLETE THE PROCESS. HIGH LEVELS OF GLUCOSE LEAD TO CELLULAR OXIDATION, WHICH TRIGGERS THE PROCESS OF DNA DEMETHYLATION AIDED BY TET ENZYMES, RESULTING IN EPIGENETIC DYSREGULATION OF THE DAMAGED TISSUES. 2017 13 1967 38 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 5305 47 PROTEOMICS ANALYSIS OF HUMAN OBESITY REVEALS THE EPIGENETIC FACTOR HDAC4 AS A POTENTIAL TARGET FOR OBESITY. SEDENTARY LIFESTYLE AND EXCESSIVE ENERGY INTAKE ARE PROMINENT CONTRIBUTORS TO OBESITY; A MAJOR RISK FACTORS FOR THE DEVELOPMENT OF INSULIN RESISTANCE, TYPE 2 DIABETES AND CARDIOVASCULAR DISEASES. ELUCIDATING THE MOLECULAR MECHANISMS UNDERLYING THESE CHRONIC CONDITIONS IS OF RELEVANT IMPORTANCE AS IT MIGHT LEAD TO THE IDENTIFICATION OF NOVEL ANTI-OBESITY TARGETS. THE PURPOSE OF THE CURRENT STUDY IS TO INVESTIGATE DIFFERENTIALLY EXPRESSED PROTEINS BETWEEN LEAN AND OBESE SUBJECTS THROUGH A SHOT-GUN QUANTITATIVE PROTEOMICS APPROACH USING PERIPHERAL BLOOD MONONUCLEAR CELLS (PBMCS) EXTRACTS AS WELL AS POTENTIAL MODULATION OF THOSE PROTEINS BY PHYSICAL EXERCISE. USING THIS APPROACH, A TOTAL OF 47 PROTEINS SHOWED AT LEAST 1.5 FOLD CHANGE BETWEEN LEAN AND OBESE SUBJECTS. IN OBESE, THE PROTEOMIC PROFILING BEFORE AND AFTER 3 MONTHS OF PHYSICAL EXERCISE SHOWED DIFFERENTIAL EXPRESSION OF 38 PROTEINS. THROMBOSPONDIN 1 (TSP1) WAS AMONG THE PROTEINS THAT WERE UPREGULATED IN OBESE SUBJECTS AND THEN DECREASED BY PHYSICAL EXERCISE. CONVERSELY, THE HISTONE DEACETYLASE 4 (HDAC4) WAS DOWNREGULATED IN OBESE SUBJECTS AND THEN INDUCED BY PHYSICAL EXERCISE. THE PROTEOMIC DATA WAS FURTHER VALIDATED BY QRT-PCR, WESTERN BLOT AND IMMUNOHISTOCHEMISTRY IN BOTH PBMCS AND ADIPOSE TISSUE. WE ALSO SHOWED THAT HDAC4 LEVELS CORRELATED POSITIVELY WITH MAXIMUM OXYGEN CONSUMPTION (VO2 MAX) BUT NEGATIVELY WITH BODY MASS INDEX, PERCENT BODY FAT, AND THE INFLAMMATORY CHEMOKINE RANTES. IN FUNCTIONAL ASSAYS, OUR DATA INDICATED THAT ECTOPIC EXPRESSION OF HDAC4 SIGNIFICANTLY IMPAIRED TNF-ALPHA-DEPENDENT ACTIVATION OF NF-KAPPAB, ESTABLISHING THUS A LINK BETWEEN HDAC4 AND REGULATION OF THE IMMUNE SYSTEM. TOGETHER, THE EXPRESSION PATTERN OF HDAC4 IN OBESE SUBJECTS BEFORE AND AFTER PHYSICAL EXERCISE, ITS CORRELATION WITH VARIOUS PHYSICAL, CLINICAL AND METABOLIC PARAMETERS ALONG WITH ITS INHIBITORY EFFECT ON NF-KAPPAB ARE SUGGESTIVE OF A PROTECTIVE ROLE OF HDAC4 AGAINST OBESITY. HDAC4 COULD THEREFORE REPRESENT A POTENTIAL THERAPEUTIC TARGET FOR THE CONTROL AND MANAGEMENT OF OBESITY AND PRESUMABLY INSULIN RESISTANCE. 2013 15 4879 24 OVERLAPPING SIGNATURES OF CHRONIC PAIN IN THE DNA METHYLATION LANDSCAPE OF PREFRONTAL CORTEX AND PERIPHERAL T CELLS. WE TESTED THE HYPOTHESIS THAT EPIGENETIC MECHANISMS IN THE BRAIN AND THE IMMUNE SYSTEM ARE ASSOCIATED WITH CHRONIC PAIN. GENOME-WIDE DNA METHYLATION ASSESSED IN 9 MONTHS POST NERVE-INJURY (SNI) AND SHAM RATS, IN THE PREFRONTAL CORTEX (PFC) AS WELL AS IN T CELLS REVEALED A VAST DIFFERENCE IN THE DNA METHYLATION LANDSCAPE IN THE BRAIN BETWEEN THE GROUPS AND A REMARKABLE OVERLAP (72%) BETWEEN DIFFERENTIALLY METHYLATED PROBES IN T CELLS AND PREFRONTAL CORTEX. DNA METHYLATION STATES IN THE PFC SHOWED ROBUST CORRELATION WITH PAIN SCORE OF ANIMALS IN SEVERAL GENES INVOLVED IN PAIN. FINALLY, ONLY 11 DIFFERENTIALLY METHYLATED PROBES IN T CELLS WERE SUFFICIENT TO DISTINGUISH SNI OR SHAM INDIVIDUAL RATS. THIS STUDY SUPPORTS THE PLAUSIBILITY OF DNA METHYLATION INVOLVEMENT IN CHRONIC PAIN AND DEMONSTRATES THE POTENTIAL FEASIBILITY OF DNA METHYLATION MARKERS IN T CELLS AS NONINVASIVE BIOMARKERS OF CHRONIC PAIN SUSCEPTIBILITY. 2016 16 344 41 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 17 1503 38 DNA METHYLATION AND GENE EXPRESSION DIFFERENCES IN CHILDREN CONCEIVED IN VITRO OR IN VIVO. EPIDEMIOLOGICAL DATA INDICATE THAT CHILDREN CONCEIVED IN VITRO HAVE A GREATER RELATIVE RISK OF LOW BIRTH-WEIGHT, MAJOR AND MINOR BIRTH DEFECTS, AND RARE DISORDERS INVOLVING IMPRINTED GENES, SUGGESTING THAT EPIGENETIC CHANGES MAY BE ASSOCIATED WITH ASSISTED REPRODUCTION. WE EXAMINED DNA METHYLATION AT MORE THAN 700 GENES (1536 CPG SITES) IN PLACENTA AND CORD BLOOD AND MEASURED GENE EXPRESSION LEVELS OF A SUBSET OF GENES THAT DIFFERED IN METHYLATION LEVELS BETWEEN CHILDREN CONCEIVED IN VITRO VERSUS IN VIVO. OUR RESULTS SUGGEST THAT IN VITRO CONCEPTION IS ASSOCIATED WITH LOWER MEAN METHYLATION AT CPG SITES IN PLACENTA AND HIGHER MEAN METHYLATION AT CPG SITES IN CORD BLOOD. WE ALSO FIND THAT IN VITRO CONCEPTION-ASSOCIATED DNA METHYLATION DIFFERENCES ARE ASSOCIATED WITH GENE EXPRESSION DIFFERENCES AT BOTH IMPRINTED AND NON-IMPRINTED GENES. THE RANGE OF INTER-INDIVIDUAL VARIATION IN GENE EXPRESSION OF THE IN VITRO AND IN VIVO GROUPS OVERLAPS SUBSTANTIALLY BUT SOME INDIVIDUALS FROM THE IN VITRO GROUP DIFFER FROM THE IN VIVO GROUP MEAN BY MORE THAN TWO STANDARD DEVIATIONS. SEVERAL OF THE GENES WHOSE EXPRESSION DIFFERS BETWEEN THE TWO GROUPS HAVE BEEN IMPLICATED IN CHRONIC METABOLIC DISORDERS, SUCH AS OBESITY AND TYPE II DIABETES. THESE FINDINGS SUGGEST THAT THERE MAY BE EPIGENETIC DIFFERENCES IN THE GAMETES OR EARLY EMBRYOS DERIVED FROM COUPLES UNDERGOING TREATMENT FOR INFERTILITY. ALTERNATIVELY, ASSISTED REPRODUCTION TECHNOLOGY MAY HAVE AN EFFECT ON GLOBAL PATTERNS OF DNA METHYLATION AND GENE EXPRESSION. IN EITHER CASE, THESE DIFFERENCES OR CHANGES MAY AFFECT LONG-TERM PATTERNS OF GENE EXPRESSION. 2009 18 101 41 A RAT METHYL-SEQ PLATFORM TO IDENTIFY EPIGENETIC CHANGES ASSOCIATED WITH STRESS EXPOSURE. AS GENOMES OF A WIDER VARIETY OF ANIMALS BECOME AVAILABLE, THERE IS AN INCREASING NEED FOR TOOLS THAT CAN CAPTURE DYNAMIC EPIGENETIC CHANGES IN THESE ANIMAL MODELS. THE RAT IS ONE PARTICULAR MODEL ANIMAL WHERE AN EPIGENETIC TOOL CAN COMPLEMENT MANY PHARMACOLOGICAL AND BEHAVIORAL STUDIES TO PROVIDE INSIGHTFUL MECHANISTIC INFORMATION. TO THIS END, WE ADAPTED THE SURESELECT TARGET CAPTURE SYSTEM (REFERRED TO AS METHYL-SEQ) FOR THE RAT, WHICH CAN ASSESS DNA METHYLATION LEVELS ACROSS THE RAT GENOME. THE RAT DESIGN TARGETED PROMOTERS, CPG ISLANDS, ISLAND SHORES, AND GC-RICH REGIONS FROM ALL REFSEQ GENES. TO IMPLEMENT THE PLATFORM ON A RAT EXPERIMENT, MALE SPRAGUE DAWLEY RATS WERE EXPOSED TO CHRONIC VARIABLE STRESS FOR 3 WEEKS, AFTER WHICH BLOOD SAMPLES WERE COLLECTED FOR GENOMIC DNA EXTRACTION. METHYL-SEQ LIBRARIES WERE CONSTRUCTED FROM THE RAT DNA SAMPLES BY SHEARING, ADAPTER LIGATION, TARGET ENRICHMENT, BISULFITE CONVERSION, AND MULTIPLEXING. LIBRARIES WERE SEQUENCED ON A NEXT-GENERATION SEQUENCING PLATFORM AND THE SEQUENCED READS WERE ANALYZED TO IDENTIFY DMRS BETWEEN DNA OF STRESSED AND UNSTRESSED RATS. TOP CANDIDATE DMRS WERE INDEPENDENTLY VALIDATED BY BISULFITE PYROSEQUENCING TO CONFIRM THE ROBUSTNESS OF THE PLATFORM. RESULTS DEMONSTRATE THAT THE RAT METHYL-SEQ PLATFORM IS A USEFUL EPIGENETIC TOOL THAT CAN CAPTURE METHYLATION CHANGES INDUCED BY EXPOSURE TO STRESS. 2018 19 287 37 AGING AND CHRONIC SUN EXPOSURE CAUSE DISTINCT EPIGENETIC CHANGES IN HUMAN SKIN. EPIGENETIC CHANGES ARE WIDELY CONSIDERED TO PLAY AN IMPORTANT ROLE IN AGING, BUT EXPERIMENTAL EVIDENCE TO SUPPORT THIS HYPOTHESIS HAS BEEN SCARCE. WE HAVE USED ARRAY-BASED ANALYSIS TO DETERMINE GENOME-SCALE DNA METHYLATION PATTERNS FROM HUMAN SKIN SAMPLES AND TO INVESTIGATE THE EFFECTS OF AGING, CHRONIC SUN EXPOSURE, AND TISSUE VARIATION. OUR RESULTS REVEAL A HIGH DEGREE OF TISSUE SPECIFICITY IN THE METHYLATION PATTERNS AND ALSO SHOWED VERY LITTLE INTERINDIVIDUAL VARIATION WITHIN TISSUES. DATA STRATIFICATION BY AGE REVEALED THAT DNA FROM OLDER INDIVIDUALS WAS CHARACTERIZED BY A SPECIFIC HYPERMETHYLATION PATTERN AFFECTING LESS THAN 1% OF THE MARKERS ANALYZED. INTERESTINGLY, STRATIFICATION BY SUN EXPOSURE PRODUCED A FUNDAMENTALLY DIFFERENT PATTERN WITH A SIGNIFICANT TREND TOWARDS HYPOMETHYLATION. OUR RESULTS THUS IDENTIFY DEFINED AGE-RELATED DNA METHYLATION CHANGES AND SUGGEST THAT THESE ALTERATIONS MIGHT CONTRIBUTE TO THE PHENOTYPIC CHANGES ASSOCIATED WITH SKIN AGING. 2010 20 6311 31 THE RELATION BETWEEN DNA METHYLATION PATTERNS AND SERUM CYTOKINE LEVELS IN COMMUNITY-DWELLING ADULTS: A PRELIMINARY STUDY. BACKGROUND: THE LEVELS OF CIRCULATING CYTOKINES FLUCTUATE WITH AGE, ACUTE ILLNESS, AND CHRONIC DISEASE, AND ARE PREDICTIVE OF MORTALITY; THIS IS ALSO TRUE FOR PATTERNS OF DNA (CPG) METHYLATION. GIVEN THAT IMMUNE CELLS ARE PARTICULARLY SENSITIVE TO CHANGES IN THE CONCENTRATION OF CYTOKINES IN THEIR MICROENVIRONMENT, WE HYPOTHESIZED THAT SERUM LEVELS OF TNF, IL-6, IL-8 AND IL-10 WOULD CORRELATE WITH GENOME-WIDE ALTERATIONS IN THE DNA METHYLATION LEVELS OF BLOOD LEUKOCYTES. TO TEST THIS, WE EVALUATED COMMUNITY-DWELLING ADULTS (N = 14; 48-78 YEARS OLD) RECRUITED TO A PILOT STUDY FOR THE CANADIAN LONGITUDINAL STUDY ON AGING (CLSA), EXAMINING DNA METHYLATION PATTERNS IN PERIPHERAL BLOOD MONONUCLEAR CELLS USING THE ILLUMINA HUMANMETHYLATION 450 K BEADCHIP. RESULTS: WE SHOW THAT, APART FROM AGE, SERUM IL-10 LEVELS EXHIBITED THE MOST SUBSTANTIAL ASSOCIATION TO DNA METHYLATION PATTERNS, FOLLOWED BY TNF, IL-6 AND IL-8. FURTHERMORE, WHILE THE LEVELS OF THESE CYTOKINES WERE HIGHER IN ELDERLY ADULTS, NO ASSOCIATIONS WITH EPIGENETIC ACCELERATED AGING, DERIVED USING THE EPIGENETIC CLOCK, WERE OBSERVED. CONCLUSIONS: AS A PRELIMINARY STUDY WITH A SMALL SAMPLE SIZE, THE CONCLUSIONS DRAWN FROM THIS WORK MUST BE VIEWED WITH CAUTION; HOWEVER, OUR OBSERVATIONS ARE ENCOURAGING AND CERTAINLY WARRANT MORE SUITABLY POWERED STUDIES OF THIS RELATIONSHIP. 2017