1 3857 145 ISCHEMIA- REPERFUSION INJURY AND ITS INFLUENCE ON THE EPIGENETIC MODIFICATION OF THE DONOR KIDNEY GENOME. BACKGROUND: IN CLINICAL TRANSPLANTATION, ISCHEMIA-REPERFUSION INJURY (I/RI) CAUSES DAMAGE TO DNA. WE HYPOTHESIZE THAT ONE FORM OF DAMAGE IS THE DEMETHYLATION OF METHYLATED CYTOSINES IN THE DONOR GENOME CAUSED BY THE OXIDATIVE ENVIRONMENT CREATED FIRST BY ISCHEMIA, AND SUBSEQUENTLY BY REPERFUSION ON TRANSPLANTATION. THIS STUDY CONTRIBUTES TO THE UNDERSTANDING OF HOW THE SHORT-LIVED AND TRANSIENT ISCHEMIC INSULT MAY INFLUENCE CHRONIC PATHOLOGICAL CHANGES THAT OCCUR IN CLINICAL TRANSPLANTATION IN THE LONG TERM. METHODS: A MODEL OF I/RI AND CHRONIC REJECTION; FISHER TO FISHER KIDNEY TRANSPLANT RENDERED COLD-ISCHEMIC FOR 4 HR BEFORE TRANSPLANTATION, TO INDUCE ANTIGEN-INDEPENDENT CHRONIC NEPHROPATHY OVER A 6-MONTH PERIOD, WAS USED. TISSUE WAS ASSESSED BY HISTOPATHOLOGY AND METHYLATION BY PYROSEQUENCING ANALYSIS. RESULTS: AN EPIGENETIC MAP OF THE RAT RENAL C3 PROMOTER WAS PRODUCED, WHICH IDENTIFIED METHYLATED CYTOSINE PHOSPHO GUANINE (CPG) SITES COINCIDENT TO CYTOKINE RESPONSE ELEMENTS AND NUCLEAR FACTOR KAPPA-LIGHT-CHAIN-ENHANCER OF ACTIVATED B CELLS (NF-KAPPAB) BINDING SITES. PYROSEQUENCING ANALYSIS SHOWED THAT THE TISSUE THAT HAD UNDERGONE 4 HR ISCHEMIA AND REPERFUSION DEVELOPED ABERRANT DEMETHYLATION OF CYTOSINES IN PUTATIVE REGULATORY SITES WITHIN THE C3 PROMOTER. CONCLUSION: THESE FINDINGS MAY DESCRIBE A NEWLY RECOGNIZED PHENOMENA IN THE FIELD OF TRANSPLANTATION. ABERRANT DEMETHYLATION HAS LONG BEEN LINKED TO THE DEVELOPMENT OF TUMORS, AND OUR DATA SUGGEST A SIMILAR MECHANISM OF GENE DYSREGULATION THAT MAY BE INITIATED BY I/RI WITH ACUTE AND CHRONIC EFFECTS. THESE DATA MAY CONTRIBUTE TO A FURTHER UNDERSTANDING OF HOW THE SHORT LIVED AND TRANSIENT ISCHEMIC INSULT INFLUENCES CHRONIC PATHOLOGICAL CHANGES THAT OCCUR EVEN IN THE ABSENCE OF MAJOR HISTOCOMPATIBILITY COMPLEX DISPARITY IN TRANSPLANTATION. 2008 2 3058 42 GENOME-WIDE DNA METHYLATION ANALYSIS IN RENAL ISCHEMIA REPERFUSION INJURY. RENAL ISCHEMIA REPERFUSION INJURY (IRI) IS FREQUENTLY ENCOUNTERED AFTER KIDNEY TRANSPLANTATION AND IS A LEADING CAUSE OF ACUTE RENAL FAILURE. ABERRANT GENE EXPRESSION AND EPIGENETIC REGULATION OCCUR DURING THE PATHOPHYSIOLOGY OF IRI. IN THIS STUDY, WE USED REDUCED REPRESENTATION BISULFITE SEQUENCING TO IDENTIFY THE DNA METHYLOME OF RENAL TISSUES DURING IRI AND THE SHAM-OPERATED TISSUES IN C57BL/6. THE METHYLATION STATUS OF APPROXIMATELY 1.29 MILLION CPGS LOCATED IN AN AVERAGE OF 11554 CPG ISLANDS AND 17113 PROMOTERS IN GENOME WAS DETERMINED. COMPARED WITH SHAM-OPERATED KIDNEY, BOTH ACUTE AND CHRONIC IRI SIGNIFICANTLY DECREASED THE GENOME-WIDE METHYLATION LEVEL (1.1-1.8%) AND THE CPG METHYLATION LEVEL IN THE PROMOTER (0.4-0.5%), CPG ISLAND (0.5-1.3%), EXON (1.3-1.9%), AND INTRON (0.8-1.1%; ALL P<10(-153)). THE PROMOTERS OF 200, 191, AND 79 GENES WERE DIFFERENTIALLY METHYLATED IN THE RENAL TISSUES AT 24H, 7DAYS, AND AT BOTH THE TIME POINTS AFTER IRI, RESPECTIVELY. AMONG THE 79 GENES, WHICH WERE CONSISTENTLY EPIGENETICALLY REGULATED AT TWO TIME POINTS, 18 GENES (22.8%) SHOWED DIFFERENTIAL EXPRESSION AFTER IRI IN A PREVIOUS STUDY OF RENAL EXPRESSION. WE VALIDATED THE PROMOTER METHYLATION STATUS AND EXPRESSION OF FIVE OUT OF THE 18 GENES, INCLUDING 2700049A03RIK, CCR9, FGD2, PFKFB3, AND SDC4 IN AN INDEPENDENT RENAL TISSUE COHORT. WE FOUND THAT ALL THE FIVE GENES EXHIBITED ALTERED METHYLATION OF PROMOTER (P=0.009-0.0001) FOLLOWING RENAL INJURY. THE PROMOTER METHYLATION OF 2700049A03RIK AND CCR9 WAS NEGATIVELY CORRELATED WITH THEIR MRNA EXPRESSION IN RENAL TISSUES (P<0.001 AND P<0.0001, RESPECTIVELY). OUR STUDY NOT ONLY DEMONSTRATED A GENOME-WIDE DNA METHYLATION PATTERN IN THE IR-INJURED RENAL TISSUE FOR THE FIRST TIME, BUT ALSO INDICATED THAT THE REGULATION OF PROMOTER METHYLATION IS AN IMPORTANT MECHANISM UNDERLYING PERSISTENT ALTERATION OF GENE EXPRESSION. 2017 3 3858 36 ISCHEMIA-INDUCED DNA HYPERMETHYLATION DURING KIDNEY TRANSPLANT PREDICTS CHRONIC ALLOGRAFT INJURY. BACKGROUND ISCHEMIA DURING KIDNEY TRANSPLANT CAUSES CHRONIC ALLOGRAFT INJURY AND ADVERSELY AFFECTS OUTCOME, BUT THE UNDERLYING MECHANISMS ARE INCOMPLETELY UNDERSTOOD. IN TUMORS, OXYGEN SHORTAGE REDUCES THE DNA DEMETHYLATING ACTIVITY OF THE TEN-11 TRANSLOCATION (TET) ENZYMES, YIELDING HYPERMETHYLATED GENOMES THAT PROMOTE TUMOR PROGRESSION. WE INVESTIGATED WHETHER ISCHEMIA SIMILARLY INDUCES DNA HYPERMETHYLATION IN KIDNEY TRANSPLANTS AND CONTRIBUTES TO CHRONIC INJURY.METHODS WE PROFILED GENOME-WIDE DNA METHYLATION IN THREE COHORTS OF BRAIN-DEAD DONOR KIDNEY ALLOGRAFT BIOPSY SPECIMENS: A LONGITUDINAL COHORT WITH PAIRED BIOPSY SPECIMENS OBTAINED AT ALLOGRAFT PROCUREMENT (PREISCHEMIA; N=13), AFTER IMPLANTATION AND REPERFUSION (POSTISCHEMIA; N=13), AND AT 3 OR 12 MONTHS AFTER TRANSPLANT (N=5 EACH); A CROSS-SECTIONAL COHORT WITH PREIMPLANTATION BIOPSY SPECIMENS (N=82); AND A CROSS-SECTIONAL COHORT WITH POSTREPERFUSION BIOPSY SPECIMENS (N=46).RESULTS ANALYSIS OF THE PAIRED PREISCHEMIA AND POSTISCHEMIA SPECIMENS REVEALED THAT METHYLATION INCREASED DRASTICALLY IN ALL ALLOGRAFTS ON ISCHEMIA. HYPERMETHYLATION WAS CAUSED BY LOSS OF 5-HYDROXYMETHYLCYTOSINE, THE PRODUCT OF TET ACTIVITY, AND IT WAS STABLE 1 YEAR AFTER TRANSPLANT. IN THE PREIMPLANTATION COHORT, CPG HYPERMETHYLATION DIRECTLY CORRELATED WITH ISCHEMIA TIME AND FOR SOME CPGS, INCREASED 2.6% PER ADDITIONAL HOUR OF ISCHEMIA. HYPERMETHYLATION PREFERENTIALLY AFFECTED AND REDUCED THE EXPRESSION OF GENES INVOLVED IN SUPPRESSING KIDNEY INJURY AND FIBROSIS. MOREOVER, CPG HYPERMETHYLATION IN PREIMPLANTATION SPECIMENS PREDICTED CHRONIC INJURY, PARTICULARLY FIBROSIS AND GLOMERULOSCLEROSIS, 1 YEAR AFTER TRANSPLANT. THIS FINDING WAS VALIDATED IN THE INDEPENDENT POSTREPERFUSION COHORT, IN WHICH HYPERMETHYLATION ALSO PREDICTED REDUCED ALLOGRAFT FUNCTION 1 YEAR AFTER TRANSPLANT, OUTPERFORMING ESTABLISHED CLINICAL VARIABLES.CONCLUSIONS WE HIGHLIGHT A NOVEL EPIGENETIC BASIS FOR ISCHEMIA-INDUCED CHRONIC ALLOGRAFT INJURY WITH BIOMARKER POTENTIAL. 2018 4 982 41 CHRONIC PRENATAL HYPOXIA INDUCES EPIGENETIC PROGRAMMING OF PKCEPSILON GENE REPRESSION IN RAT HEARTS. RATIONALE: EPIDEMIOLOGICAL STUDIES DEMONSTRATE A CLEAR ASSOCIATION OF ADVERSE INTRAUTERINE ENVIRONMENT WITH AN INCREASED RISK OF ISCHEMIC HEART DISEASE IN ADULTHOOD. HYPOXIA IS A COMMON STRESS TO THE FETUS AND RESULTS IN DECREASED PROTEIN KINASE C EPSILON (PKCEPSILON) EXPRESSION IN THE HEART AND INCREASED CARDIAC VULNERABILITY TO ISCHEMIA AND REPERFUSION INJURY IN ADULT OFFSPRING IN RATS. OBJECTIVES: THE PRESENT STUDY TESTED THE HYPOTHESIS THAT FETAL HYPOXIA-INDUCED METHYLATION OF CYTOSINE-PHOSPHATE-GUANINE DINUCLEOTIDES AT THE PKCEPSILON PROMOTER IS REPRESSIVE AND CONTRIBUTES TO PKCEPSILON GENE REPRESSION IN THE HEART OF ADULT OFFSPRING. METHODS AND RESULTS: HYPOXIC TREATMENT OF PREGNANT RATS FROM DAYS 15 TO 21 OF GESTATION RESULTED IN SIGNIFICANT DECREASES IN PKCEPSILON PROTEIN AND MRNA IN FETAL HEARTS. SIMILAR RESULTS WERE OBTAINED IN EX VIVO HYPOXIC TREATMENT OF ISOLATED FETAL HEARTS AND RAT EMBRYONIC VENTRICULAR MYOCYTE CELL LINE H9C2. INCREASED METHYLATION OF PKCEPSILON PROMOTER AT SP1 BINDING SITES, -346 AND -268, WERE DEMONSTRATED IN BOTH FETAL HEARTS OF MATERNAL HYPOXIA AND H9C2 CELLS TREATED WITH 1% O(2) FOR 24 HOURS. WHEREAS HYPOXIA HAD NO SIGNIFICANT EFFECT ON THE BINDING AFFINITY OF SP1 TO THE UNMETHYLATED SITES IN H9C2 CELLS, HEARTS OF FETUSES AND ADULT OFFSPRING, METHYLATION OF BOTH SP1 SITES REDUCED SP1 BINDING. THE ADDITION OF 5-AZA-2'-DEOXYCYTIDINE BLOCKED THE HYPOXIA-INDUCED INCREASE IN METHYLATION OF BOTH SP1 BINDING SITES AND RESTORED PKCEPSILON MRNA AND PROTEIN TO THE CONTROL LEVELS. IN HEARTS OF BOTH FETUSES AND ADULT OFFSPRING, HYPOXIA-INDUCED METHYLATION OF SP1 SITES WAS SIGNIFICANTLY GREATER IN MALES THAN IN FEMALES, AND DECREASED PKCEPSILON MRNA WAS SEEN ONLY IN MALES. IN FETAL HEARTS, THERE WAS SIGNIFICANTLY HIGHER ABUNDANCE OF ESTROGEN RECEPTOR ALPHA AND BETA ISOFORMS IN FEMALES THAN IN MALES. BOTH ESTROGEN RECEPTOR ALPHA AND BETA INTERACTED WITH THE SP1 BINDING SITES IN THE FETAL HEART, WHICH MAY EXPLAIN THE SEX DIFFERENCES IN SP1 METHYLATION IN THE FETAL HEART. ADDITIONALLY, SELECTIVE ACTIVATION OF PKCEPSILON RESTORED THE HYPOXIA-INDUCED CARDIAC VULNERABILITY TO ISCHEMIC INJURY IN OFFSPRING. CONCLUSIONS: THE FINDINGS DEMONSTRATE A DIRECT EFFECT OF HYPOXIA ON EPIGENETIC MODIFICATION OF DNA METHYLATION AND PROGRAMMING OF CARDIAC PKCEPSILON GENE REPRESSION IN A SEX-DEPENDENT MANNER, LINKING FETAL HYPOXIA AND PATHOPHYSIOLOGICAL CONSEQUENCES IN THE HEARTS OF ADULT OFFSPRING. 2010 5 3460 33 HYPOMETHYLATION OF THE IL8 PROMOTER IN NASAL EPITHELIAL CELLS OF PATIENTS WITH CHRONIC RHINOSINUSITIS WITH NASAL POLYPS. BACKGROUND: IL-8 IS AN IMPORTANT CHEMOKINE IMPLICATED IN THE PATHOGENESIS OF CHRONIC RHINOSINUSITIS (CRS), BUT LITTLE IS KNOWN ABOUT EPIGENETIC REGULATION OF IL8 IN THE PATHOGENESIS OF CRS. OBJECTIVE: WE SOUGHT TO INVESTIGATE THE RELATIONSHIP BETWEEN THE DNA METHYLATION LEVEL IN THE IL8 PROXIMAL PROMOTER AND CRS IN HAN CHINESE SUBJECTS. METHODS: PATIENTS WITH CHRONIC RHINOSINUSITIS WITH NASAL POLYPS (CRSWNP; N = 187), PATIENTS WITH CHRONIC RHINOSINUSITIS WITHOUT NASAL POLYPS (CRSSNP; N = 89), AND CONTROL SUBJECTS (N = 57) WERE ENROLLED IN 2 INDEPENDENT COHORTS. PURIFIED HUMAN NASAL EPITHELIAL CELLS FROM EACH PARTICIPANT WERE ASSESSED FOR PERCENTAGE DNA METHYLATION OF CPG SITES IN THE IL8 PROXIMAL PROMOTER BY USING BISULFITE PYROSEQUENCING AND FOR FUNCTIONAL ASPECTS OF METHYLATION STATUS BY USING IN VITRO ASSAYS. RESULTS: DNA METHYLATION OF CPG SITES 1, 2, AND 3, RESPECTIVELY, IN THE IL8 PROXIMAL PROMOTER WAS SIGNIFICANTLY DECREASED IN HUMAN NASAL EPITHELIAL CELLS OF PATIENTS WITH CRSWNP COMPARED WITH THAT IN PATIENTS WITH CRSSNP (P < .001) AND CONTROL SUBJECTS (P < .001). PERCENTAGE OF DNA METHYLATION OF THE CPG3 SITE WAS CORRELATED NEGATIVELY WITH BOTH TISSUE EOSINOPHILIC CATIONIC PROTEIN (P < .01) AND MYELOPEROXIDASE (P < .05) LEVELS. IL-1BETA (P < .001) AND TNF-ALPHA (P < .01) SIGNIFICANTLY INCREASED IL8 EXPRESSION ACCOMPANIED BY A REDUCTION IN METHYLATION AT THE CPG3 SITE (P < .001). ELECTROPHORETIC MOBILITY SHIFT ASSAYS DEMONSTRATED THAT METHYLATION STATUS OF CPG3 CHANGED THE BINDING OF OCTAMER-BINDING TRANSCRIPTION FACTOR 1 AND NUCLEAR FACTOR KAPPAB. CONCLUSION: DECREASED DNA METHYLATION OF PARTICULARLY CPG SITES IN THE IL8 PROXIMAL PROMOTER MIGHT PLAY A ROLE IN THE PATHOGENESIS OF CRSWNP. 2019 6 3856 36 ISCHAEMIA REPERFUSION INJURY: MECHANISMS OF PROGRESSION TO CHRONIC GRAFT DYSFUNCTION. THE INCREASING USE OF EXTENDED CRITERIA ORGANS TO MEET THE DEMAND FOR KIDNEY TRANSPLANTATION RAISES AN IMPORTANT QUESTION OF HOW THE SEVERITY OF EARLY ISCHAEMIC INJURY INFLUENCES LONG-TERM OUTCOMES. SIGNIFICANT ACUTE ISCHAEMIC KIDNEY INJURY IS ASSOCIATED WITH DELAYED GRAFT FUNCTION, INCREASED IMMUNE-ASSOCIATED EVENTS AND, ULTIMATELY, EARLIER DETERIORATION OF GRAFT FUNCTION. A COMPREHENSIVE UNDERSTANDING OF IMMEDIATE MOLECULAR EVENTS THAT ENSUE POST-ISCHAEMIA AND THEIR POTENTIAL LONG-TERM CONSEQUENCES ARE KEY TO THE DISCOVERY OF NOVEL THERAPEUTIC TARGETS. ACUTE ISCHAEMIC INJURY PRIMARILY AFFECTS TUBULAR STRUCTURE AND FUNCTION. DEPENDING ON THE SEVERITY AND PERSISTENCE OF THE INSULT, THIS MAY RESOLVE COMPLETELY, LEADING TO RESTORATION OF NORMAL FUNCTION, OR BE SUSTAINED, RESULTING IN PERSISTENT RENAL IMPAIRMENT AND PROGRESSIVE FUNCTIONAL LOSS. LONG-TERM EFFECTS OF ACUTE RENAL ISCHAEMIA ARE MEDIATED BY SEVERAL MECHANISMS INCLUDING HYPOXIA, HIF-1 ACTIVATION, ENDOTHELIAL DYSFUNCTION LEADING TO VASCULAR RAREFACTION, SUSTAINED PRO-INFLAMMATORY STIMULI INVOLVING INNATE AND ADAPTIVE IMMUNE RESPONSES, FAILURE OF TUBULAR CELLS TO RECOVER AND EPIGENETIC CHANGES. THIS REVIEW DESCRIBES THE BIOLOGICAL RELEVANCE AND INTERACTION OF THESE MECHANISMS BASED ON CURRENTLY AVAILABLE EVIDENCE. 2019 7 245 37 ADRENERGIC REPRESSION OF THE EPIGENETIC READER MECP2 FACILITATES CARDIAC ADAPTATION IN CHRONIC HEART FAILURE. RATIONALE: IN CHRONIC HEART FAILURE, INCREASED ADRENERGIC ACTIVATION CONTRIBUTES TO STRUCTURAL REMODELING AND ALTERED GENE EXPRESSION. ALTHOUGH ADRENERGIC SIGNALING ALTERS HISTONE MODIFICATIONS, IT IS UNKNOWN, WHETHER IT ALSO AFFECTS OTHER EPIGENETIC PROCESSES, INCLUDING DNA METHYLATION AND ITS RECOGNITION. OBJECTIVE: THE AIM OF THIS STUDY WAS TO IDENTIFY THE MECHANISM OF REGULATION OF THE METHYL-CPG-BINDING PROTEIN 2 (MECP2) AND ITS FUNCTIONAL SIGNIFICANCE DURING CARDIAC PRESSURE OVERLOAD AND UNLOADING. METHODS AND RESULTS: MECP2 WAS IDENTIFIED AS A REVERSIBLY REPRESSED GENE IN MOUSE HEARTS AFTER TRANSVERSE AORTIC CONSTRICTION AND WAS NORMALIZED AFTER REMOVAL OF THE CONSTRICTION. SIMILARLY, MECP2 REPRESSION IN HUMAN FAILING HEARTS RESOLVED AFTER UNLOADING BY A LEFT VENTRICULAR ASSIST DEVICE. THE CLUSTER MIR-212/132 WAS UPREGULATED AFTER TRANSVERSE AORTIC CONSTRICTION OR ON ACTIVATION OF ALPHA1- AND BETA1-ADRENOCEPTORS AND MIR-212/132 LED TO REPRESSION OF MECP2. PREVENTION OF MECP2 REPRESSION BY A CARDIOMYOCYTE-SPECIFIC, DOXYCYCLINE-REGULATABLE TRANSGENIC MOUSE MODEL AGGRAVATED CARDIAC HYPERTROPHY, FIBROSIS, AND CONTRACTILE DYSFUNCTION AFTER TRANSVERSE AORTIC CONSTRICTION. ABLATION OF MECP2 IN CARDIOMYOCYTES FACILITATED RECOVERY OF FAILING HEARTS AFTER REVERSIBLE TRANSVERSE AORTIC CONSTRICTION. GENOME-WIDE EXPRESSION ANALYSIS, CHROMATIN IMMUNOPRECIPITATION EXPERIMENTS, AND DNA METHYLATION ANALYSIS IDENTIFIED MITOCHONDRIAL GENES AND THEIR TRANSCRIPTIONAL REGULATORS AS MECP2 TARGET GENES. COINCIDENT WITH ITS REPRESSION, MECP2 WAS REMOVED FROM ITS TARGET GENES, WHEREAS DNA METHYLATION OF MECP2 TARGET GENES REMAINED STABLE DURING PRESSURE OVERLOAD. CONCLUSIONS: THESE DATA CONNECT ADRENERGIC ACTIVATION WITH A MICRORNA-MECP2 EPIGENETIC PATHWAY THAT IS IMPORTANT FOR CARDIAC ADAPTATION DURING THE DEVELOPMENT AND RECOVERY FROM HEART FAILURE. 2015 8 3410 38 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 9 274 32 AGE-RELATED CHANGES IN DNA METHYLATION AFFECT RENAL HISTOLOGY AND POST-TRANSPLANT FIBROSIS. DURING AGEING, KIDNEY FUNCTION DECREASES DUE TO RENAL TUBULAR ATROPHY, INTERSTITIAL FIBROSIS, GLOMERULOSCLEROSIS AND ARTERIOSCLEROSIS. RECENTLY, CHANGES IN DNA METHYLATION WERE SHOWN TO CONTRIBUTE TO VARIOUS AGEING PROCESSES. HOWEVER, IT IS UNKNOWN WHETHER SUCH CHANGES ALSO CONTRIBUTE TO AGE-RELATED KIDNEY DYSFUNCTION. TO ASSESS THIS, WE PROFILED GENOME-WIDE CHANGES IN DNA METHYLATION (OVER 800 000 CPG SITES) IN 95 RENAL BIOPSIES OBTAINED PRIOR TO KIDNEY TRANSPLANTATION FROM DONORS AGED 16 TO 73 YEARS. DONOR AGE SIGNIFICANTLY ASSOCIATED WITH THE METHYLATION OF 92 778 CPGS (FALSE DISCOVERY RATE UNDER 0.05), CORRESPONDING TO 10 285 DIFFERENTIALLY METHYLATED REGIONS. THESE REGIONS WERE MOST FREQUENTLY LOCATED IN GENES INVOLVED IN THE WNT/BETA-CATENIN SIGNALING PATHWAY. USING AN INDEPENDENT COHORT OF 67 BIOPSIES, WE AUTONOMOUSLY VALIDATED THESE FINDINGS. INTERESTINGLY, THE METHYLATION STATUS OF THESE 92 778 AGE-RELATED CPGS WAS ASSOCIATED WITH GLOMERULOSCLEROSIS (34.4% OF CPGS AT A FALSE DISCOVERY RATE UNDER 0.05) AND INTERSTITIAL FIBROSIS (0.9%) AND GRAFT FUNCTION AT ONE YEAR AFTER TRANSPLANTATION, BUT NOT WITH TUBULAR ATROPHY AND ARTERIOSCLEROSIS. NO ASSOCIATION WAS OBSERVED WITH ANY OF THESE PATHOLOGIES AT THE TIME OF TRANSPLANTATION (0% AT A FALSE DISCOVERY RATE UNDER 0.05). THUS, AGE-ASSOCIATED CHANGES IN DNA METHYLATION AT THE TIME OF TRANSPLANTATION PREDICT FUTURE INJURY OF TRANSPLANTED KIDNEYS. SPECIFICALLY, OUR EPIGENOME-WIDE ASSOCIATION STUDY DEMONSTRATES THAT EPIGENETIC RENAL AGEING IS IMPLICATED IN PROGRESSIVE FIBROSIS IN BOTH THE GLOMERULUS AND THE INTERSTITIUM. 2019 10 2300 30 EPIGENETIC REGULATION OF BDNF EXPRESSION IN THE PRIMARY SENSORY NEURONS AFTER PERIPHERAL NERVE INJURY: IMPLICATIONS IN THE DEVELOPMENT OF NEUROPATHIC PAIN. BRAIN-DERIVED NEUROTROPHIC FACTOR (BDNF) IS KNOWN TO BE UP-REGULATED IN THE DORSAL ROOT GANGLION (DRG) AFTER PERIPHERAL NERVE INJURY, AND TO CONTRIBUTE TO NEUROPATHIC PAIN. HERE, WE FOUND THAT THERMAL HYPERALGESIA AND MECHANICAL ALLODYNIA AT DAY 7 POST-INJURY WERE INHIBITED ONLY WHEN ANTI-BDNF ANTIBODY WAS INTRATHECALLY ADMINISTRATED AT DAY 2 POST-INJURY. CONSISTENT WITH BEHAVIORAL RESULTS, WESTERN BLOT ANALYSIS SHOWED THAT THE EXPRESSION LEVELS OF BDNF PROTEIN IN THE SPINAL DORSAL HORN WERE MARKEDLY INDUCED DURING EARLY STAGE POST-INJURY. MOREOVER, THE MAXIMAL INCREASE IN BDNF MRNA EXPRESSION IN THE DRG WAS OBSERVED AT DAY 1 POST-INJURY, AND SIGNIFICANTLY ELEVATED LEVELS WERE SUSTAINED FOR AT LEAST 14 DAYS. FOUR OF FIVE BDNF MRNA TRANSCRIPTS WERE UP-REGULATED AFTER NERVE INJURY, AND THE MOST INDUCIBLE TRANSCRIPT WAS EXON I. USING A CHROMATIN IMMUNOPRECIPITATION (CHIP) ASSAY, WE FOUND THAT NERVE INJURY PROMOTES HISTONE H3 AND H4 ACETYLATION, TRANSCRIPTIONALLY ACTIVE MODIFICATIONS, AT BDNF PROMOTER I AT DAY 1 POST-INJURY, AND THE LEVELS OF HISTONE ACETYLATION REMAIN ELEVATED FOR AT LEAST 7 DAYS. TAKEN TOGETHER, OUR FINDINGS SUGGEST THAT AN INITIAL INCREASE IN BDNF EXON I EXPRESSION CONTROLLED BY EPIGENETIC MECHANISMS MIGHT HAVE A CRUCIAL ROLE IN THE DEVELOPMENT OF NEUROPATHIC PAIN. 2013 11 766 35 CCL5 SUPPRESSES KLOTHO EXPRESSION VIA P-STAT3/DNA METHYLTRANSFERASE1-MEDIATED PROMOTER HYPERMETHYLATION. BACKGROUND: ENHANCED INFLAMMATION AND REDUCED KLOTHO ARE COMMON FEATURES IN CHRONIC KIDNEY DISEASE (CKD). INFLAMMATION INDUCES DNA HYPERMETHYLATION. THIS STUDY ASSESSED THE PERFORMANCE OF INFLAMMATORY MARKER C-C MOTIF CHEMOKINE 5 (CCL5) IN EPIGENETIC REGULATION OF KLOTHO EXPRESSION. METHODS: FIFTY CKD PATIENTS AND 25 MATCHED CONTROLS WERE ENROLLED, AND SERUM CCL5 LEVEL, SKLOTHO LEVEL, AND DNA METHYLATION WERE EVALUATED IN THESE SUBJECTS. A RENAL INTERSTITIAL FIBROSIS (RIF) MODEL WITH CKD WAS INDUCED IN MICE VIA UNILATERAL URETERAL OBSTRUCTION (UUO) IN VIVO AND HUMAN PROXIMAL TUBULAR EPITHELIAL (HK-2) CELLS TREATED WITH CCL5 IN VITRO. 5-AZA-2'-DEOXYCYTIDINE (5-AZA), A DNA METHYLTRANSFERASE INHIBITOR WAS GIVEN TO UUO MICE. HEMATOXYLIN AND EOSIN (HE) AND MASSON TRICHROME STAINING WERE ADOPTED TO EVALUATE RENAL PATHOLOGICAL CHANGES. METHYLATION-SPECIFIC PCR WAS PERFORMED TO ASSESS DNA METHYLATION OF KLOTHO PROMOTER IN THE PERIPHERAL BLOOD LEUCOCYTES (PBLS) FROM CKD PATIENTS AND OBSTRUCTIVE KIDNEY FROM UUO MICE. CCL5, KLOTHO, AND DNA METHYLTRANSFERASES (DNMTS) WERE DETERMINED BY ELISAS, IMMUNOFLUORESCENCE, OR WESTERN BLOTTING. HK-2 CELLS WERE EXPOSED TO CCL5 WITH OR WITHOUT 5-AZA AND STATTIC, A P-SIGNAL TRANSDUCER AND ACTIVATOR OF TRANSCRIPTION 3 (STAT3) INHIBITOR, AND EXPRESSIONS OF P-STAT3, DNMT1, AND KLOTHO WERE DETERMINED BY WESTERN BLOTTING. RESULTS: CCL5 UPREGULATION CONCOMITANT WITH KLOTHO DOWNREGULATION IN SERUM AND GLOBAL DNA METHYLATION IN PBLS WERE OBSERVED IN CKD SAMPLES. UUO CONTRIBUTED TO SEVERE RENAL INTERSTITIAL FIBROSIS AND ENHANCED EXPRESSIONS OF FIBROTIC MARKERS. MOREOVER, UUO INCREASED THE CCL5 LEVEL, INDUCED KLOTHO PROMOTER METHYLATION, SUPPRESSED KLOTHO LEVEL, ACTIVATED P-STAT3 SIGNALING, AND UPREGULATED DNMT1 LEVEL. A SIMILAR OBSERVATION WAS MADE IN HK-2 CELLS TREATED WITH CCL5. MORE IMPORTANTLY, 5-AZA INHIBITED UUO-INDUCED KLOTHO HYPERMETHYLATION, REVERSED KLOTHO, DOWNREGULATED P-STAT3 EXPRESSIONS, AND AMELIORATED RIF IN VIVO. THE CONSISTENT FINDINGS IN VITRO WERE ALSO OBTAINED IN HK-2 CELLS EXPOSED TO 5-AZA AND STATTIC. CONCLUSION: THE CCL5/P-STAT3/DNMT1 AXIS IS IMPLICATED IN EPIGENETIC REGULATION OF KLOTHO EXPRESSION IN CKD. THIS STUDY PROVIDES NOVEL THERAPEUTIC POSSIBILITIES FOR REVERSAL OF KLOTHO SUPPRESSION BY CKD. 2022 12 286 37 AGING AND ALCOHOL INTERACT TO ALTER HEPATIC DNA HYDROXYMETHYLATION. BACKGROUND: AGING AND CHRONIC ALCOHOL CONSUMPTION ARE BOTH MODIFIERS OF DNA METHYLATION, BUT IT IS NOT YET KNOWN WHETHER CHRONIC ALCOHOL CONSUMPTION ALSO ALTERS DNA HYDROXYMETHYLATION, A NEWLY DISCOVERED EPIGENETIC MARK PRODUCED BY OXIDATION OF METHYLCYTOSINE. FURTHERMORE, IT HAS NOT BEEN TESTED WHETHER AGING AND ALCOHOL INTERACT TO MODIFY THIS EPIGENETIC PHENOMENON, THEREBY HAVING AN INDEPENDENT EFFECT ON GENE EXPRESSION. METHODS: OLD (18 MONTHS) AND YOUNG (4 MONTHS) MALE C57BL/6 MICE WERE PAIR-FED EITHER A LIEBER-DECARLI LIQUID DIET WITH ALCOHOL (18% OF ENERGY) OR AN ISOCALORIC LIEBER-DECARLI CONTROL DIET FOR 5 WEEKS. GLOBAL DNA HYDROXYMETHYLATION AND DNA METHYLATION WERE ANALYZED FROM HEPATIC DNA USING A NEW LIQUID CHROMATOGRAPHY-TANDEM MASS SPECTROMETRY METHOD. HEPATIC MRNA EXPRESSION OF THE TET ENZYMES WERE MEASURED VIA QUANTITATIVE REAL-TIME POLYMERASE CHAIN REACTION. RESULTS: IN YOUNG MICE, MILD CHRONIC ALCOHOL EXPOSURE SIGNIFICANTLY REDUCED GLOBAL DNA HYDROXYMETHYLATION COMPARED WITH CONTROL MICE (0.22 +/- 0.01 VS. 0.29 +/- 0.06%, P = 0.004). ALCOHOL DID NOT SIGNIFICANTLY ALTER HYDROXYMETHYLCYTOSINE LEVELS IN OLD MICE. OLD MICE FED THE CONTROL DIET SHOWED DECREASED GLOBAL DNA HYDROXYMETHYLATION COMPARED WITH YOUNG MICE FED THE CONTROL DIET (0.24 +/- 0.02 VS. 0.29 +/- 0.06%, P = 0.04). THIS MODEL SUGGESTS AN INTERACTION BETWEEN AGING AND ALCOHOL IN DETERMINING DNA HYDROXYMETHYLATION (PINTERACTION = 0.009). EXPRESSION OF TET2 AND TET3 WAS DECREASED IN THE OLD MICE RELATIVE TO THE YOUNG (P < 0.005). CONCLUSIONS: THE OBSERVATION THAT ALCOHOL ALTERS DNA HYDROXYMETHYLATION INDICATES A NEW EPIGENETIC EFFECT OF ALCOHOL. THIS IS THE FIRST STUDY DEMONSTRATING THE INTERACTIVE EFFECTS OF CHRONIC ALCOHOL CONSUMPTION AND AGING ON DNA HYDROXYMETHYLATION. 2014 13 3841 28 IRON SUPPLEMENTATION REVERSES THE REDUCTION OF HYDROXYMETHYLCYTOSINE IN HEPATIC DNA ASSOCIATED WITH CHRONIC ALCOHOL CONSUMPTION IN RATS. BACKGROUND: ALCOHOL IS KNOWN TO AFFECT TWO EPIGENETIC PHENOMENA, DNA METHYLATION AND DNA HYDROXYMETHYLATION, AND IRON IS A COFACTOR OF TEN-ELEVEN TRANSLOCATION (TET) ENZYMES THAT CATALYZE THE CONVERSION FROM METHYLCYTOSINE TO HYDROXYMETHYLCYTOSINE. IN THE PRESENT STUDY WE AIMED TO DETERMINE THE EFFECTS OF ALCOHOL ON DNA HYDROXYMETHYLATION AND FURTHER EFFECTS OF IRON ON ALCOHOL ASSOCIATED EPIGENETIC CHANGES. METHODS: TWENTY-FOUR MALE SPRAGUE-DAWLEY RATS WERE FED EITHER LIEBER-DECARLI ALCOHOL DIET (36% CALORIES FROM ETHANOL) OR LIEBER-DECARLI CONTROL DIET ALONG WITH OR WITHOUT IRON SUPPLEMENTATION (0.6% CARBONYL IRON) FOR 8 WEEKS. HEPATIC NON-HEME IRON CONCENTRATIONS WERE MEASURED BY COLORIMETRIC ASSAYS. PROTEIN LEVELS OF HEPATIC FERRITIN AND TRANSFERRIN RECEPTOR WERE DETERMINED BY WESTERN BLOTTING. METHYLCYTOSINE, HYDROXYMETHYLCYTOSINE AND UNMODIFIED CYTOSINE IN DNA WERE SIMULTANEOUSLY MEASURED BY LIQUID CHROMATOGRAPHY/MASS SPECTROMETRY METHOD. RESULTS: IRON SUPPLEMENTATION SIGNIFICANTLY INCREASED HEPATIC NON-HEME IRON CONTENTS (P < 0.05) BUT ALCOHOL ALONE DID NOT. HOWEVER, BOTH ALCOHOL AND IRON SIGNIFICANTLY INCREASED HEPATIC FERRITIN LEVELS AND DECREASED HEPATIC TRANSFERRIN RECEPTOR LEVELS (P < 0.05). ALCOHOL REDUCED HEPATIC DNA HYDROXYMETHYLATION (0.21% +/- 0.04% VS. 0.33% +/- 0.04%, P = 0.01) COMPARED TO CONTROL, WHILE IRON SUPPLEMENTATION TO ALCOHOL DIET DID NOT CHANGE DNA HYDROXYMETHYLATION. THERE WAS NO SIGNIFICANT DIFFERENCE IN METHYLCYTOSINE LEVELS, WHILE UNMODIFIED CYTOSINE LEVELS WERE SIGNIFICANTLY INCREASED IN ALCOHOL-FED GROUPS COMPARED TO CONTROL (95.61% +/- 0.08% VS. 95.26% +/- 0.12%, P = 0.03), SUGGESTING THAT ALCOHOL FURTHER INCREASES THE CONVERSION FROM HYDROXYMETHYLCYTOSINE TO UNMODIFIED CYTOSINE. CONCLUSIONS: CHRONIC ALCOHOL CONSUMPTION ALTERS GLOBAL DNA HYDROXYMETHYLATION IN THE LIVER BUT IRON SUPPLEMENTATION REVERSES THE EPIGENETIC EFFECT OF ALCOHOL. 2016 14 3809 33 INTRAPERITONEAL 5-AZACYTIDINE ALLEVIATES NERVE INJURY-INDUCED PAIN IN RATS BY MODULATING DNA METHYLATION. TO INVESTIGATE THE ROLE OF DNA METHYLATION IN MODULATING CHRONIC NEUROPATHIC PAIN (NPP), IDENTIFY POSSIBLE TARGET GENES OF DNA METHYLATION INVOLVED IN THIS PROCESS, AND PRELIMINARILY CONFIRM THE MEDICINAL VALUE OF THE DNA METHYLTRANSFERASES (DNMTS) INHIBITOR 5-AZACYTIDINE (5-AZA) IN NPP BY TARGETING GENE METHYLATION. TWO RAT NPP MODELS, CHRONIC CONSTRICTION INJURY (CCI) AND SPINAL NERVE LIGATION (SNL), WERE USED. THE DNA METHYLATION PROFILES IN THE LUMBAR SPINAL CORD WERE ASSAYED USING AN ARRAYSTAR RAT REFSEQ PROMOTER ARRAY. THE UNDERLYING GENES WITH DIFFERENTIAL METHYLATION WERE THEN IDENTIFIED AND SUBMITTED TO GENE ONTOLOGY AND PATHWAY ANALYSIS. METHYL-DNA IMMUNOPRECIPITATION QUANTITATIVE PCR (MEDIP-QPCR) AND QUANTITATIVE REVERSE TRANSCRIPTION-PCR (RT-QPCR) WERE USED TO CONFIRM GENE METHYLATION AND EXPRESSION. THE PROTECTIVE FUNCTION OF 5-AZA IN NPP AND GENE EXPRESSION WERE EVALUATED VIA BEHAVIORAL ASSAYS AND RT-QPCR, RESPECTIVELY. ANALYSIS OF THE DNA METHYLATION PATTERNS IN THE LUMBAR SPINAL CORD INDICATED THAT 1205 DIFFERENTIALLY METHYLATED FRAGMENTS IN CCI RATS WERE LOCATED WITHIN DNA PROMOTER REGIONS, INCLUDING 638 HYPERMETHYLATED FRAGMENTS AND 567 HYPOMETHYLATED FRAGMENTS. THE METHYLATION LEVELS OF GRM4, HTR4, ADRB2, KCNF1, GAD2, AND PPARG, WHICH ARE ASSOCIATED WITH LONG-TERM POTENTIATION (LTP) AND GLUTAMATERGIC SYNAPSE PATHWAYS, WERE INCREASED WITH A CORRESPONDING DECREASE IN THEIR MRNA EXPRESSION, IN THE SPINAL CORDS OF CCI RATS. MOREOVER, WE FOUND THAT THE INTRAPERITONEAL INJECTION OF 5-AZA (4 MG/KG) ATTENUATED CCI- OR SNL-INDUCED MECHANICAL ALLODYNIA AND THERMAL HYPERALGESIA. FINALLY, THE MRNA EXPRESSION OF HYPERMETHYLATED GENES SUCH AS GRM4, HTR4, ADRB2, KCNF1, AND GAD2 WAS REVERSED AFTER 5-AZA TREATMENT. CCI INDUCED WIDESPREAD METHYLATION CHANGES IN THE DNA PROMOTER REGIONS IN THE LUMBAR SPINAL CORD. INTRAPERITONEAL 5-AZA ALLEVIATED HYPERALGESIA IN CCI AND SNL RATS, AN EFFECT ACCOMPANIED BY THE REVERSED EXPRESSION OF HYPERMETHYLATED GENES. THUS, DNA METHYLATION INHIBITION REPRESENTS A PROMISING EPIGENETIC STRATEGY FOR PROTECTION AGAINST CHRONIC NPP FOLLOWING NERVE INJURY. OUR STUDY LAYS A THEORETICAL FOUNDATION FOR 5-AZA TO BECOME A CLINICAL TARGETED DRUG. 2023 15 1620 29 DNA METHYLTRANSFERASE-MEDIATED TRANSCRIPTIONAL SILENCING IN MALIGNANT GLIOMA: A COMBINED WHOLE-GENOME MICROARRAY AND PROMOTER ARRAY ANALYSIS. EPIGENETIC INACTIVATION OF TUMOR SUPPRESSOR GENES IS A COMMON FEATURE IN HUMAN CANCER. PROMOTER HYPERMETHYLATION AND HISTONE DEACETYLATION ARE REVERSIBLE EPIGENETIC MECHANISMS ASSOCIATED WITH TRANSCRIPTIONAL REGULATION. DNA METHYLTRANSFERASES (DNMT1 AND DNMT3B) REGULATE AND MAINTAIN PROMOTER METHYLATION AND ARE OVEREXPRESSED IN HUMAN CANCER. WE PERFORMED WHOLE-GENOME MICROARRAY ANALYSIS TO IDENTIFY GENES WITH ALTERED EXPRESSION AFTER RNAI-INDUCED SUPPRESSION OF DNMT IN A GLIOBLASTOMA MULTIFORME (GBM) CELL LINE. WE THEN IDENTIFIED GENES WITH BOTH DECREASED EXPRESSION AND EVIDENCE OF PROMOTER CPG ISLAND HYPERMETHYLATION IN GBM TISSUE SAMPLES USING A COMBINED WHOLE-GENOME MICROARRAY TRANSCRIPTOME ANALYSIS IN CONJUNCTION WITH A PROMOTER ARRAY ANALYSIS AFTER DNA IMMUNOPRECIPITATION WITH ANTI-5-METHYLCYTIDINE. DNMT1 AND 3B KNOCKDOWN RESULTED IN THE RESTORED EXPRESSION OF 308 GENES THAT ALSO CONTAINED PROMOTER REGION HYPERMETHYLATION. OF THESE, 43 WERE ALSO FOUND TO BE DOWNREGULATED IN GBM TISSUE SAMPLES. THREE DOWNREGULATED GENES WITH HYPERMETHYLATED PROMOTERS AND RESTORED EXPRESSION IN RESPONSE TO ACUTE DNMT SUPPRESSION WERE ASSAYED FOR METHYLATION CHANGES USING BISULFITE SEQUENCE ANALYSIS OF THE PROMOTER REGION AFTER CHRONIC DNMT SUPPRESSION. RESTORATION OF GENE EXPRESSION WAS NOT ASSOCIATED WITH CHANGES IN PROMOTER REGION METHYLATION, BUT RATHER WITH CHANGES IN HISTONE METHYLATION AND CHROMATIN CONFORMATION. TWO OF THE IDENTIFIED GENES EXHIBITED GROWTH SUPPRESSIVE ACTIVITY IN IN VITRO ASSAYS. COMBINING TARGETED GENETIC MANIPULATIONS WITH COMPREHENSIVE GENOMIC AND EXPRESSION ANALYSES PROVIDES A POTENTIALLY POWERFUL NEW APPROACH FOR IDENTIFYING EPIGENETICALLY REGULATED GENES IN GBM. 2009 16 3082 44 GENOME-WIDE REDISTRIBUTION OF MECP2 IN DORSAL ROOT GANGLIA AFTER PERIPHERAL NERVE INJURY. BACKGROUND: METHYL-CPG-BINDING PROTEIN 2 (MECP2), A PROTEIN WITH AFFINITY FOR METHYLATED CYTOSINES, IS CRUCIAL FOR NEURONAL DEVELOPMENT AND FUNCTION. MECP2 REGULATES GENE EXPRESSION THROUGH ACTIVATION, REPRESSION AND CHROMATIN REMODELING. MUTATIONS IN MECP2 CAUSE RETT SYNDROME, AND THESE PATIENTS DISPLAY IMPAIRED NOCICEPTION. WE OBSERVED AN INCREASE IN MECP2 EXPRESSION IN MOUSE DORSAL ROOT GANGLIA (DRG) AFTER PERIPHERAL NERVE INJURY. THE FUNCTIONAL IMPLICATION OF INCREASED MECP2 IS LARGELY UNKNOWN. TO IDENTIFY REGIONS OF THE GENOME BOUND BY MECP2 IN THE DRG AND THE CHANGES INDUCED BY NERVE INJURY, A CHROMATIN IMMUNOPRECIPITATION OF MECP2 FOLLOWED BY SEQUENCING (CHIP-SEQ) WAS PERFORMED 4 WEEKS AFTER SPARED NERVE INJURY (SNI). RESULTS: WHILE THE NUMBER OF BINDING SITES ACROSS THE GENOME REMAINED SIMILAR IN THE SNI MODEL AND SHAM CONTROL, SNI INDUCED THE REDISTRIBUTION OF MECP2 TO TRANSCRIPTIONALLY RELEVANT REGIONS. TO DETERMINE HOW DIFFERENTIAL BINDING OF MECP2 CAN AFFECT GENE EXPRESSION IN THE DRG, WE INVESTIGATED MMU-MIR-126, A MICRORNA LOCUS THAT HAD ENRICHED MECP2 BINDING IN THE SNI MODEL. ENRICHED MECP2 BINDING TO MIR-126 LOCUS AFTER NERVE INJURY REPRESSED MIR-126 EXPRESSION, AND THIS WAS NOT MEDIATED BY ALTERATIONS IN METHYLATION PATTERN AT THE MIR-126 LOCUS. DOWNREGULATION OF MIR-126 RESULTED IN THE UPREGULATION OF ITS TWO TARGET GENES DNMT1 AND VEGFA IN NEURO 2A CELLS AND IN SNI MODEL COMPARED TO CONTROL. THESE TARGET GENES WERE SIGNIFICANTLY DOWNREGULATED IN MECP2-NULL MICE COMPARED TO WILD-TYPE LITTERMATES, INDICATING A REGULATORY ROLE FOR MECP2 IN ACTIVATING DNMT1 AND VEGFA EXPRESSION. INTRATHECAL DELIVERY OF MIR-126 WAS NOT SUFFICIENT TO REVERSE NERVE INJURY-INDUCED MECHANICAL AND THERMAL HYPERSENSITIVITY, BUT DECREASED DNMT1 AND VEGFA EXPRESSION IN THE DRG. CONCLUSIONS: OUR STUDY SHOWS A REGULATORY ROLE FOR MECP2 IN THAT CHANGES IN GLOBAL REDISTRIBUTION CAN RESULT IN DIRECT AND INDIRECT MODULATION OF GENE EXPRESSION IN THE DRG. ALTERATIONS IN GENOME-WIDE BINDING OF MECP2 THEREFORE PROVIDE A MOLECULAR BASIS FOR A BETTER UNDERSTANDING OF EPIGENETIC REGULATION-INDUCED MOLECULAR CHANGES UNDERLYING NERVE INJURY. 2016 17 6702 40 VEGFA PROMOTER GENE HYPERMETHYLATION AT HIF1ALPHA BINDING SITE IS AN EARLY CONTRIBUTOR TO CKD PROGRESSION AFTER RENAL ISCHEMIA. CHRONIC HYPOXIA IS A MAJOR CONTRIBUTOR TO CHRONIC KIDNEY DISEASE (CKD) AFTER ACUTE KIDNEY INJURY (AKI). HOWEVER, THE TEMPORAL RELATION BETWEEN THE ACUTE INSULT AND MALADAPTIVE RENAL RESPONSE TO HYPOXIA REMAINS UNCLEAR. IN THIS STUDY, WE ANALYZED THE TIME-COURSE OF RENAL HEMODYNAMICS, OXIDATIVE STRESS, INFLAMMATION, AND FIBROSIS, AS WELL AS EPIGENETIC MODIFICATIONS, WITH FOCUS ON HIF1ALPHA/VEGF SIGNALING, IN THE AKI TO CKD TRANSITION. SHAM-OPERATED, RIGHT NEPHRECTOMY (UNX), AND UNX PLUS RENAL ISCHEMIA (IR + UNX) GROUPS OF RATS WERE INCLUDED AND STUDIED AT 1, 2, 3, OR 4 MONTHS. THE IR + UNX GROUP DEVELOPED CKD CHARACTERIZED BY PROGRESSIVE PROTEINURIA, RENAL DYSFUNCTION, TUBULAR PROLIFERATION, AND FIBROSIS. AT FIRST MONTH POST-ISCHEMIA, THERE WAS A TWOFOLD SIGNIFICANT INCREASE IN OXIDATIVE STRESS AND REDUCTION IN GLOBAL DNA METHYLATION THAT WAS MAINTAINED THROUGHOUT THE STUDY. HIF1ALPHA AND VEGFA EXPRESSION WERE DEPRESSED IN THE FIRST AND SECOND-MONTHS POST-ISCHEMIA, AND THEN HIF1ALPHA BUT NOT VEGFA EXPRESSION WAS RECOVERED. INTERESTINGLY, HYPERMETHYLATION OF THE VEGFA PROMOTER GENE AT THE HIF1ALPHA BINDING SITE WAS FOUND, SINCE EARLY STAGES OF THE CKD PROGRESSION. OUR FINDINGS SUGGEST THAT RENAL HYPOPERFUSION, INEFFICIENT HYPOXIC RESPONSE, INCREASED OXIDATIVE STRESS, DNA HYPOMETHYLATION, AND, VEGFA PROMOTER GENE HYPERMETHYLATION AT HIF1ALPHA BINDING SITE, ARE EARLY DETERMINANTS OF AKI-TO-CKD TRANSITION. 2021 18 2418 36 EPIGENETIC SIGNATURE OF CHRONIC LOW BACK PAIN IN HUMAN T CELLS. OBJECTIVE: DETERMINE IF CHRONIC LOW BACK PAIN (LBP) IS ASSOCIATED WITH DNA METHYLATION SIGNATURES IN HUMAN T CELLS THAT WILL REVEAL NOVEL MECHANISMS AND POTENTIAL THERAPEUTIC TARGETS AND EXPLORE THE FEASIBILITY OF EPIGENETIC DIAGNOSTIC MARKERS FOR PAIN-RELATED PATHOPHYSIOLOGY. METHODS: GENOME-WIDE DNA METHYLATION ANALYSIS OF 850,000 CPG SITES IN WOMEN AND MEN WITH CHRONIC LBP AND PAIN-FREE CONTROLS WAS PERFORMED. T CELLS WERE ISOLATED (DISCOVERY COHORT, N = 32) AND USED TO IDENTIFY DIFFERENTIALLY METHYLATED CPG SITES, AND GENE ONTOLOGIES AND MOLECULAR PATHWAYS WERE IDENTIFIED. A POLYGENIC DNA METHYLATION SCORE FOR LBP WAS GENERATED IN BOTH WOMEN AND MEN. VALIDATION WAS PERFORMED IN AN INDEPENDENT COHORT (VALIDATION COHORT, N = 63) OF CHRONIC LBP AND HEALTHY CONTROLS. RESULTS: ANALYSIS WITH THE DISCOVERY COHORT REVEALED A TOTAL OF 2,496 AND 419 DIFFERENTIALLY METHYLATED CPGS IN WOMEN AND MEN, RESPECTIVELY. IN WOMEN, MOST OF THESE SITES WERE HYPOMETHYLATED AND ENRICHED IN GENES WITH FUNCTIONS IN THE EXTRACELLULAR MATRIX, IN THE IMMUNE SYSTEM (IE, CYTOKINES), OR IN EPIGENETIC PROCESSES. IN MEN, A UNIQUE CHRONIC LBP DNA METHYLATION SIGNATURE WAS IDENTIFIED CHARACTERIZED BY SIGNIFICANT ENRICHMENT FOR GENES FROM THE MAJOR HISTOCOMPATIBILITY COMPLEX. SEX-SPECIFIC POLYGENIC DNA METHYLATION SCORES WERE GENERATED TO ESTIMATE THE PAIN STATUS OF EACH INDIVIDUAL AND CONFIRMED IN THE VALIDATION COHORT USING PYROSEQUENCING. CONCLUSION: THIS STUDY REVEALS SEX-SPECIFIC DNA METHYLATION SIGNATURES IN HUMAN T CELLS THAT DISCRIMINATES CHRONIC LBP PARTICIPANTS FROM HEALTHY CONTROLS. 2021 19 6589 37 TUMOR NECROSIS FACTOR-ALPHA GENE PROMOTER METHYLATION IN JAPANESE ADULTS WITH CHRONIC PERIODONTITIS AND RHEUMATOID ARTHRITIS. BACKGROUND AND OBJECTIVE: OVER-EXPRESSION OF TUMOR NECROSIS FACTOR-ALPHA (TNF-ALPHA) PLAYS A PATHOLOGICAL ROLE IN CHRONIC PERIODONTITIS (CP) AND RHEUMATOID ARTHRITIS (RA), WHICH MIGHT BE REGULATED BY THE EPIGENETIC MECHANISM. THE AIM OF THE PRESENT STUDY WAS TO EVALUATE WHETHER THERE IS A UNIQUE METHYLATION PROFILE OF THE TNF-ALPHA GENE PROMOTER IN BLOOD CELLS OF INDIVIDUALS WITH CP AND RA. MATERIAL AND METHODS: THE STUDY PARTICIPANTS CONSISTED OF 30 JAPANESE ADULTS WITH RA (RA GROUP), 30 RACE-MATCHED ADULTS WITH CP ONLY (CP GROUP) AND 30 RACE-MATCHED HEALTHY CONTROLS (H GROUP). GENOMIC DNA ISOLATED FROM PERIPHERAL BLOOD WAS MODIFIED BY SODIUM BISULFITE AND ANALYZED, BY DIRECT SEQUENCING, TO INVESTIGATE DNA METHYLATION OF THE TNF-ALPHA GENE PROMOTER REGION. THE LEVEL OF TNF-ALPHA PRODUCED IN MONONUCLEAR CELLS STIMULATED WITH PORPHYROMONAS GINGIVALIS LIPOPOLYSACCHARIDE WAS DETERMINED USING ELISA. RESULTS: TWELVE CYTOSINE-GUANINE DINUCLEOTIDE (CPG) MOTIFS WERE IDENTIFIED IN THE TNF-ALPHA PROMOTER FRAGMENT FROM -343 TO +57 BP. THE CP GROUP SHOWED A SIGNIFICANTLY HIGHER METHYLATION RATE AND FREQUENCY AT -72 BP THAN THE H GROUP (P < 0.01). THE RA GROUP EXHIBITED SIGNIFICANTLY HIGHER METHYLATION RATES AT SEVEN CPG MOTIFS (-302, -163, -119, -72, -49, -38 AND +10 BP), AND SIGNIFICANTLY HIGHER METHYLATION FREQUENCIES AT SIX CPG MOTIFS (-163, -119, -72, -49, -38 AND +10 BP), THAN THE H GROUP (P < 0.01 FOR ALL COMPARISONS). THE LEVELS OF TNF-ALPHA PRODUCED WERE SIGNIFICANTLY DIFFERENT BETWEEN INDIVIDUALS WITH AND WITHOUT METHYLATION AT -163 BP (P = 0.03). CONCLUSION: THESE RESULTS SUGGEST THAT THE HYPERMETHYLATED STATUS OF CPG MOTIFS IN THE TNF-ALPHA GENE PROMOTER IN BLOOD CELLS MAY BE UNIQUE TO JAPANESE ADULTS WITH CP AND RA. 2016 20 4017 37 LOW-DOSE HYDRALAZINE REDUCES ALBUMINURIA AND GLOMERULOSCLEROSIS IN A MOUSE MODEL OF OBESITY-RELATED CHRONIC KIDNEY DISEASE. AIM: TO DETERMINE, USING A MOUSE MODEL OF OBESITY, WHETHER LOW-DOSE HYDRALAZINE PREVENTS OBESITY-RELATED CHRONIC KIDNEY DISEASE (CKD). METHODS: FROM 8 WEEKS OF AGE, MALE C57BL/6 MICE RECEIVED A HIGH-FAT DIET (HFD) OR CHOW, WITH OR WITHOUT LOW-DOSE HYDRALAZINE (25 MG/L) IN DRINKING WATER, FOR 24 WEEKS. BIOMETRIC AND METABOLIC VARIABLES, RENAL FUNCTION AND STRUCTURAL CHANGES, RENAL GLOBAL DNA METHYLATION, DNA METHYLATION PROFILE AND MARKERS OF RENAL FIBROSIS, INJURY, INFLAMMATION AND OXIDATIVE STRESS WERE ASSESSED. RESULTS: THE HFD-FED MICE DEVELOPED OBESITY, WITH GLUCOSE INTOLERANCE, HYPERINSULINAEMIA AND DYSLIPIDAEMIA. OBESITY INCREASED ALBUMINURIA AND GLOMERULOSCLEROSIS, WHICH WERE SIGNIFICANTLY AMELIORATED BY LOW-DOSE HYDRALAZINE IN THE ABSENCE OF A BLOOD PRESSURE-LOWERING EFFECT. OBESITY INCREASED RENAL GLOBAL DNA METHYLATION AND THIS WAS ATTENUATED BY LOW-DOSE HYDRALAZINE. HFD-INDUCED CHANGES IN METHYLATION OF INDIVIDUAL LOCI WERE ALSO SIGNIFICANTLY REVERSED BY LOW-DOSE HYDRALAZINE. OBESE MICE DEMONSTRATED INCREASED MARKERS OF KIDNEY FIBROSIS, INFLAMMATION AND OXIDATIVE STRESS, BUT THESE MARKERS WERE NOT SIGNIFICANTLY IMPROVED BY HYDRALAZINE. CONCLUSION: LOW-DOSE HYDRALAZINE AMELIORATED HFD-INDUCED ALBUMINURIA AND GLOMERULOSCLEROSIS, INDEPENDENT OF ALTERATIONS IN BIOMETRIC AND METABOLIC VARIABLES OR BLOOD PRESSURE REGULATION. ALTHOUGH THE PRECISE MECHANISM OF RENOPROTECTION IN OBESITY IS UNCLEAR, AN EPIGENETIC BASIS MAY BE IMPLICATED. THESE DATA SUPPORT REPURPOSING HYDRALAZINE AS A NOVEL THERAPY TO PREVENT CKD PROGRESSION IN OBESE PATIENTS. 2022