1 4033 137 M6A HYPOMETHYLATION OF DNMT3B REGULATED BY ALKBH5 PROMOTES INTERVERTEBRAL DISC DEGENERATION VIA E4F1 DEFICIENCY. BACKGROUND: THE INTERVERTEBRAL DISC (IVD) DEGENERATION IS THE LEADING CAUSE OF LOW BACK PAIN, WHICH ACCOUNTS FOR A MAIN CAUSE OF DISABILITY. N6-METHYLADENOSINE (M6A) IS THE MOST ABUNDANT INTERNAL MODIFICATION IN EUKARYOTIC MESSENGER RNAS AND IS INVOLVED IN VARIOUS DISEASES AND CELLULAR PROCESSES BY MODULATING MRNA FATE. HOWEVER, THE CRITICAL ROLE OF M6A REGULATION IN IVD DEGENERATION REMAINS UNCLEAR. NUCLEUS PULPOSUS CELL (NPC) SENESCENCE IS CRITICAL FOR THE PROGRESSION OF IVD DEGENERATION. HERE, WE UNCOVERED THE ROLE AND EXPLORED THE REGULATORY MECHANISM OF M6A IN NPC SENESCENCE DURING IVD DEGENERATION. METHODS: IDENTIFICATION OF NPC SENESCENCE DURING IVD DEGENERATION WAS BASED ON THE ANALYSIS OF TISSUE SAMPLES AND THE CELLULAR MODEL. ALKBH5 UPREGULATION INDUCING CELLULAR SENESCENCE WAS CONFIRMED BY FUNCTIONAL EXPERIMENTS IN VIVO AND IN VITRO. CHIP-QPCR AND DNA-PULLDOWN WERE USED TO REVEAL INCREASED ALKBH5 WAS REGULATED BY KDM4A-MEDIATED H3K9ME3. FURTHERMORE, ME-RIP-SEQ WAS PERFORMED TO IDENTIFY M6A HYPOMETHYLATION OF DNMT3B TRANSCRIPTS IN SENESCENT NPCS. STABILITY ANALYSIS SHOWED THAT DNMT3B EXPRESSION WAS ENHANCED FOR LESS YTHDF2 RECOGNITION AND INCREASED DNMT3B PROMOTED NPC SENESCENCE AND IVD DEGENERATION VIA E4F1 METHYLATION BY IN VIVO AND IN VITRO ANALYSES. RESULTS: EXPRESSION OF ALKBH5 IS ENHANCED DURING IVD DEGENERATION AND NPC SENESCENCE, DUE TO DECREASED KDM4A-MEDIATED H3K9ME3 MODIFICATION. FUNCTIONALLY, ALKBH5 CAUSES NPC SENESCENCE BY DEMETHYLATING DNMT3B TRANSCRIPTS AND IN TURN PROMOTING ITS EXPRESSION VIA LESS YTHDF2 RECOGNITION AND FOLLOWING DEGRADATION DUE TO TRANSCRIPT HYPOMETHYLATION IN VITRO AND IN VIVO. INCREASED DNMT3B PROMOTES THE DEVELOPMENT OF IVD DEGENERATION AND NPC SENESCENCE, MECHANISTICALLY BY METHYLATING CPG ISLANDS OF E4F1 AT THE PROMOTER REGION AND THUS RESTRAINING ITS TRANSCRIPTION AND EXPRESSION. CONCLUSIONS: COLLECTIVELY, OUR FINDINGS REVEAL AN EPIGENETIC INTERPLAY MECHANISM IN NPC SENESCENCE AND IVD DEGENERATION, PRESENTING A CRITICAL PRO-SENESCENCE ROLE OF ALKBH5 AND M6A HYPOMETHYLATION, HIGHLIGHTING THE THERAPEUTIC POTENTIAL OF TARGETING THE M6A/DNMT3B/E4F1 AXIS FOR TREATING IVD DEGENERATION. 2022 2 6058 41 THE DEFICIENCY OF N6-METHYLADENOSINE DEMETHYLASE ALKBH5 ENHANCES THE NEURODEGENERATIVE DAMAGE INDUCED BY COBALT. COBALT EXPOSURE, EVEN AT LOW CONCENTRATIONS, INDUCES NEURODEGENERATIVE DAMAGE, SUCH AS ALZHEIMER'S DISEASE (AD). THE SPECIFIC UNDERLYING MECHANISMS REMAIN UNCLEAR. OUR PREVIOUS STUDY DEMONSTRATED THAT M(6)A METHYLATION ALTERATION IS INVOLVED IN COBALT-INDUCED NEURODEGENERATIVE DAMAGE, SUCH AS IN AD. HOWEVER, THE ROLE OF M(6)A RNA METHYLATION AND ITS UNDERLYING MECHANISMS ARE POORLY UNDERSTOOD. IN THIS STUDY, BOTH EPIDEMIOLOGICAL AND LABORATORY STUDIES SHOWED THAT COBALT EXPOSURE COULD DOWNREGULATE THE EXPRESSION OF THE M(6)A DEMETHYLASE ALKBH5, SUGGESTING A KEY ROLE FOR ALKBH5. MOREOVER, METHYLATED RNA IMMUNOPRECIPITATION AND SEQUENCING (MERIP-SEQ) ANALYSIS REVEALED THAT ALKBH5 DEFICIENCY IS ASSOCIATED WITH NEURODEGENERATIVE DISEASES. KEGG PATHWAY AND GENE ONTOLOGY ANALYSES FURTHER REVEALED THAT THE DIFFERENTIALLY M(6)A-MODIFIED GENES RESULTING FROM ALKBH5 DOWNREGULATION AND COBALT EXPOSURE WERE AGGREGATED IN THE PATHWAYS OF PROLIFERATION, APOPTOSIS, AND AUTOPHAGY. SUBSEQUENTLY, ALKBH5 DEFICIENCY WAS SHOWN TO EXACERBATE CELL VIABILITY DECLINE, MOTIVATE CELL APOPTOSIS AND ATTENUATE CELL AUTOPHAGY INDUCED BY COBALT WITH EXPERIMENTAL TECHNIQUES OF GENE OVEREXPRESSION/INHIBITION. IN ADDITION, MORPHOLOGICAL CHANGES IN NEURONS AND THE EXPRESSION OF AD-RELATED PROTEINS, SUCH AS APP, P-TAU, AND TAU, IN THE CEREBRAL HIPPOCAMPUS OF WILD-TYPE AND ALKBH5 KNOCKOUT MICE AFTER CHRONIC COBALT EXPOSURE WERE ALSO INVESTIGATED. BOTH IN VITRO AND IN VIVO RESULTS SHOWED THAT LOWER EXPRESSION OF ALKBH5 AGGRAVATED COBALT-INDUCED NEURODEGENERATIVE DAMAGE. THESE RESULTS SUGGEST THAT ALKBH5, AS AN EPIGENETIC REGULATOR, COULD BE A POTENTIAL TARGET FOR ALLEVIATING COBALT-INDUCED NEURODEGENERATIVE DAMAGE. IN ADDITION, WE PROPOSE A NOVEL STRATEGY FOR THE PREVENTION AND TREATMENT OF ENVIRONMENTAL TOXICANT-RELATED NEURODEGENERATION FROM AN EPIGENETIC PERSPECTIVE. 2023 3 2284 22 EPIGENETIC REGULATION IN INTERVERTEBRAL DISC DEGENERATION. INTERVERTEBRAL DISC (IVD) DEGENERATION IS THE LEADING CAUSE OF LOW BACK PAIN, WHICH HAS A STRIKING IMPACT ON NUMEROUS PATIENTS. THEREFORE, COMPREHENSIVELY ILLUMINATING THE REGULATORY MECHANISMS OF IVD DEGENERATION IS OF GREAT SIGNIFICANCE. HERE, WE DISCUSS THE LATEST ADVANCES IN UNDERSTANDING THE MAIN EPIGENETIC MECHANISMS REGULATING IVD DEGENERATION. 2022 4 5972 27 TET REPRESSION AND INCREASED DNMT ACTIVITY SYNERGISTICALLY INDUCE ABERRANT DNA METHYLATION. CHRONIC INFLAMMATION IS DEEPLY INVOLVED IN VARIOUS HUMAN DISORDERS, SUCH AS CANCER, NEURODEGENERATIVE DISORDERS, AND METABOLIC DISORDERS. INDUCTION OF EPIGENETIC ALTERATIONS, ESPECIALLY ABERRANT DNA METHYLATION, IS ONE OF THE MAJOR MECHANISMS, BUT HOW IT IS INDUCED IS STILL UNCLEAR. HERE, WE FOUND THAT EXPRESSION OF TET GENES, METHYLATION ERASERS, WAS DOWNREGULATED IN INFLAMED MOUSE AND HUMAN TISSUES, AND THAT THIS WAS CAUSED BY UPREGULATION OF TET-TARGETING MIRNAS SUCH AS MIR20A, MIR26B, AND MIR29C, LIKELY DUE TO ACTIVATION OF NF-KAPPAB SIGNALING DOWNSTREAM OF IL-1BETA AND TNF-ALPHA. HOWEVER, TET KNOCKDOWN INDUCED ONLY MILD ABERRANT METHYLATION. NITRIC OXIDE (NO), PRODUCED BY NOS2, ENHANCED ENZYMATIC ACTIVITY OF DNA METHYLTRANSFERASES (DNMTS), METHYLATION WRITERS, AND NO EXPOSURE INDUCED MINIMAL ABERRANT METHYLATION. IN CONTRAST, A COMBINATION OF TET KNOCKDOWN AND NO EXPOSURE SYNERGISTICALLY INDUCED ABERRANT METHYLATION, INVOLVING GENOMIC REGIONS NOT METHYLATED BY EITHER ALONE. THE RESULTS SHOWED THAT A VICIOUS COMBINATION OF TET REPRESSION, DUE TO NF-KAPPAB ACTIVATION, AND DNMT ACTIVATION, DUE TO NO PRODUCTION, IS RESPONSIBLE FOR ABERRANT METHYLATION INDUCTION IN HUMAN TISSUES. 2020 5 1615 35 DNA METHYLTRANSFERASE 3B PLAYS A PROTECTIVE ROLE AGAINST HEPATOCARCINOGENESIS CAUSED BY CHRONIC INFLAMMATION VIA MAINTAINING MITOCHONDRIAL HOMEOSTASIS. MOST HEPATOCELLULAR CARCINOMAS (HCCS) DEVELOP ON THE BASIS OF CHRONIC HEPATITIS, BUT THE MECHANISM OF EPIGENETIC REGULATION IN INFLAMMATORY HEPATOCARCINOGENESIS HAS YET TO BE ELUCIDATED. AMONG DE NOVO DNA METHYLTRANSFERASES (DNMTS), DNMT3B HAS LATELY BEEN REPORTED TO ACT SPECIFICALLY ON ACTIVELY TRANSCRIBED GENES, SUGGESTING THE POSSIBILITY THAT IT PLAYS A ROLE IN THE PATHOGENESIS OF CANCER. WE CONFIRMED THAT DNMT3B ISOFORMS LACKING ITS CATALYTIC DOMAIN WERE HIGHLY EXPRESSED IN HCCS COMPARED WITH NON-TUMOROUS LIVER TISSUE. TO ELUCIDATE THE ROLE OF DNMT3B IN HEPATOCARCINOGENESIS, WE GENERATED A GENETICALLY ENGINEERED MOUSE MODEL WITH HEPATOCYTE-SPECIFIC DNMT3B DELETION. THE LIVER OF THE DNMT3B-DEFICIENT MICE EXHIBITED AN EXACERBATION OF THIOACETAMIDE-INDUCED HEPATITIS, PROGRESSION OF LIVER FIBROSIS AND A HIGHER INCIDENCE OF HCC COMPARED WITH THE LIVER OF THE CONTROL MICE. WHOLE-GENOME BISULFITE SEQUENCING VERIFIED A LOWER CG METHYLATION LEVEL IN THE DNMT3B-DEFICIENT LIVER, DEMONSTRATING DIFFERENTIALLY METHYLATED REGIONS THROUGHOUT THE GENOME. TRANSCRIPTOME ANALYSIS REVEALED DECREASED EXPRESSION OF GENES RELATED TO OXIDATIVE PHOSPHORYLATION IN THE DNMT3B-DEFICIENT LIVER. MOREOVER, PRIMARY HEPATOCYTES ISOLATED FROM THE DNMT3B-DEFICIENT MICE SHOWED REDUCED MITOCHONDRIAL RESPIRATORY CAPACITY, LEADING TO THE ENHANCEMENT OF OXIDATIVE STRESS IN THE LIVER TISSUE. OUR FINDINGS SUGGEST THE PROTECTIVE ROLE OF DNMT3B AGAINST CHRONIC INFLAMMATION AND HCC DEVELOPMENT VIA MAINTAINING MITOCHONDRIAL HOMEOSTASIS. 2020 6 4584 30 N6-METHYLADENOSINE-METHYLOMIC LANDSCAPE OF LUNG TISSUES OF MICE WITH CHRONIC OBSTRUCTIVE PULMONARY DISEASE. CHRONIC OBSTRUCTIVE PULMONARY DISEASE (COPD), A COMMON RESPIRATORY DISEASE, CAN BE DIVIDED INTO STABLE PHASE AND ACUTE EXACERBATION PHASE (AECOPD) AND IS CHARACTERIZED BY INFLAMMATION AND HYPER-IMMUNITY. METHYLATION OF N6-METHYLADENOSINE (M6A) IS AN EPIGENETIC MODIFICATION THAT REGULATES THE EXPRESSION AND FUNCTIONS OF GENES BY INFLUENCING POST-TRANSCRIPTIONAL RNA MODIFICATIONS. ITS INFLUENCE ON THE IMMUNE REGULATION MECHANISM HAS ATTRACTED GREAT ATTENTION. HEREIN, WE PRESENT THE M6AMETHYLOMIC LANDSCAPE AND OBSERVE HOW THE METHYLATION OF M6A PARTICIPATES IN THE PATHOLOGICAL PROCESS OF COPD. THE M6A MODIFICATION OF 430 GENES INCREASED AND THAT OF 3995 GENES DECREASED IN THE LUNG TISSUES OF MICE WITH STABLE COPD. THE LUNG TISSUES OF MICE WITH AECOPD EXHIBITED 740 GENES WITH HYPERMETHYLATED M6A PEAK AND 1373 GENES WITH LOW M6A PEAK. THESE DIFFERENTIALLY METHYLATED GENES PARTICIPATED IN SIGNALING PATHWAYS RELATED TO IMMUNE FUNCTIONS. TO FURTHER CLARIFY THE EXPRESSION LEVELS OF DIFFERENTIALLY METHYLATED GENES, RNA IMMUNOPRECIPITATION SEQUENCING (MERIP-SEQ) AND RNA-SEQUENCING DATA WERE JOINTLY ANALYZED. IN THE STABLE COPD GROUP, 119 HYPERMETHYLATED MRNAS (82 UPREGULATED AND 37 DOWNREGULATED MRNAS) AND 867 HYPOMETHYLATED MRNAS (419 UPREGULATED AND 448 DOWNREGULATED MRNAS) WERE DIFFERENTIALLY EXPRESSED. IN THE AECOPD GROUP, 87 HYPERMETHYLATED MRNAS (71 UPREGULATED AND 16 DOWNREGULATED MRNAS) AND 358 HYPOMETHYLATED MRNAS (115 UPREGULATED AND 243 DOWNREGULATED MRNAS) SHOWED DIFFERENTIAL EXPRESSION. MANY MRNAS WERE RELATED TO IMMUNE FUNCTION AND INFLAMMATION. TOGETHER, THIS STUDY PROVIDES IMPORTANT EVIDENCE ON THE ROLE OF RNA METHYLATION OF M6A IN COPD. 2023 7 878 38 CHRONIC CADMIUM EXPOSURE AGGRAVATES MALIGNANT PHENOTYPES OF NASOPHARYNGEAL CARCINOMA BY ACTIVATING THE WNT/BETA-CATENIN SIGNALING PATHWAY VIA HYPERMETHYLATION OF THE CASEIN KINASE 1ALPHA PROMOTER. BACKGROUND: OUR PREVIOUS STUDY HAS SHOWN THAT CADMIUM (CD) EXPOSURE IS NOT ONLY A RISK FACTOR FOR NASOPHARYNGEAL CARCINOMA (NPC), BUT ALSO CORRELATED WITH THE CLINICAL STAGE AND LYMPH NODE METASTASIS. HOWEVER, THE UNDERLYING MOLECULAR EVENTS OF CD INVOLVED IN NPC PROGRESSION REMAIN TO BE ELUCIDATED. PURPOSE: THE OBJECTIVE OF THIS STUDY WAS TO DECIPHER HOW CD IMPACTS THE MALIGNANT PHENOTYPES OF NPC CELLS. METHODS: NPC CELL LINES CNE-1 AND CNE-2 WERE CONTINUOUSLY EXPOSED WITH 1 MUM CD CHLORIDE FOR 10 WEEKS, DESIGNATING AS CHRONIC CD TREATED NPC CELLS (CCT-NPC). MTT ASSAY, COLONY FORMATION ASSAY AND XENOGRAFT TUMOR GROWTH WERE USED TO ASSESS CELL VIABILITY IN VITRO AND IN VIVO. TRANSWELL ASSAYS WERE PERFORMED TO DETECT CELL INVASION AND MIGRATION. THE PROTEIN LEVELS OF E-CADHERIN, N-CADHERIN, VIMENTIN AS WELL AS BETA-CATENIN AND CASEIN KINASE 1ALPHA(CK1ALPHA) WERE MEASURED BY WESTERN BLOT. IMMUNOFLUORESCENCE STAINING WAS USED TO OBSERVE THE DISTRIBUTION OF FILAMENT ACTIN (F-ACTIN), BETA-CATENIN AND CK1ALPHA. THE MRNA LEVELS OF DOWNSTREAM TARGET GENES OF BETA-CATENIN WERE DETECTED BY RT-PCR. WNT/BETA-CATENIN SIGNALING ACTIVITY WAS ASSESSED BY TOPFLASH/FOPFLASH DUAL LUCIFERASE REPORT SYSTEM. MS-PCR WAS USED TO DETECT THE METHYLATION STATUS OF CK1ALPHA. FINALLY, THE ACTIVATION OF WNT/BETA-CATENIN PATHWAY AND CELL BIOLOGICAL PROPERTIES WERE EXAMINED FOLLOWING TREATMENT OF CCT-NPC CELLS WITH 5-AZA-2-DEOXY-CYTIDINE(5-AZA-CDR). RESULTS: CCT-NPC CELLS SHOWED AN INCREASE IN CELL PROLIFERATION, COLONY FORMATION, INVASION AND MIGRATION COMPARED TO THE PARENTAL CELLS. CD ALSO INDUCED CYTOSKELETON REORGANIZATION AND EPITHELIAL-TO-MESENCHYMAL TRANSITION. UPREGULATION AND NUCLEAR TRANSLOCATION OF BETA-CATENIN AND INCREASED LUCIFERASE ACTIVITY ACCOMPANIED WITH TRANSCRIPTION OF DOWNSTREAM TARGET GENES WERE FOUND IN CCT-NPC CELLS. TREATMENT OF CCT-CNE1 CELLS WITH 5-AZA-CDR COULD REVERSE THE HYPERMETHYLATION OF CK1ALPHA AND ATTENUATE THE CELL MALIGNANCY. CONCLUSION: THESE RESULTS SUPPORT A ROLE FOR CHRONIC CD EXPOSURE AS A DRIVING FORCE FOR THE MALIGNANT PROGRESSION OF NPC VIA EPIGENETIC ACTIVATION OF THE WNT/BETA-CATENIN PATHWAY. 2019 8 164 29 ABNORMAL HISTONE METHYLATION IS RESPONSIBLE FOR INCREASED VASCULAR ENDOTHELIAL GROWTH FACTOR 165A SECRETION FROM AIRWAY SMOOTH MUSCLE CELLS IN ASTHMA. VASCULAR ENDOTHELIAL GROWTH FACTOR (VEGF), A KEY ANGIOGENIC MOLECULE, IS ABERRANTLY EXPRESSED IN SEVERAL DISEASES INCLUDING ASTHMA WHERE IT CONTRIBUTES TO BRONCHIAL VASCULAR REMODELING AND CHRONIC INFLAMMATION. ASTHMATIC HUMAN AIRWAY SMOOTH MUSCLE CELLS HYPERSECRETE VEGF, BUT THE MECHANISM IS UNCLEAR. IN THIS STUDY, WE DEFINED THE MECHANISM IN HUMAN AIRWAY SMOOTH MUSCLE CELLS FROM NONASTHMATIC AND ASTHMATIC PATIENTS. WE FOUND THAT ASTHMATIC CELLS LACKED A REPRESSION COMPLEX AT THE VEGF PROMOTER, WHICH WAS PRESENT IN NONASTHMATIC CELLS. RECRUITMENT OF G9A, TRIMETHYLATION OF HISTONE H3 AT LYSINE 9 (H3K9ME3), AND A RESULTANT DECREASE IN RNA POLYMERASE II AT THE VEGF PROMOTER WAS CRITICAL TO REPRESSION OF VEGF SECRETION IN NONASTHMATIC CELLS. AT THE ASTHMATIC PROMOTER, H3K9ME3 WAS ABSENT BECAUSE OF FAILED RECRUITMENT OF G9A; RNA POLYMERASE II BINDING, IN ASSOCIATION WITH TATA-BINDING PROTEIN-ASSOCIATED FACTOR 1, WAS INCREASED; H3K4ME3 WAS PRESENT; AND SP1 BINDING WAS EXAGGERATED AND SUSTAINED. IN CONTRAST, DNA METHYLATION AND HISTONE ACETYLATION WERE SIMILAR IN ASTHMATIC AND NONASTHMATIC CELLS. THIS IS THE FIRST STUDY, TO OUR KNOWLEDGE, TO SHOW THAT AIRWAY CELLS IN ASTHMA HAVE ALTERED EPIGENETIC REGULATION OF REMODELING GENE(S). HISTONE METHYLATION AT GENES SUCH AS VEGF MAY BE AN IMPORTANT NEW THERAPEUTIC TARGET. 2012 9 3468 42 HYPOXIA-INDUCED DNA HYPERMETHYLATION IN HUMAN PULMONARY FIBROBLASTS IS ASSOCIATED WITH THY-1 PROMOTER METHYLATION AND THE DEVELOPMENT OF A PRO-FIBROTIC PHENOTYPE. BACKGROUND: PULMONARY FIBROSIS IS A DEBILITATING AND LETHAL DISEASE WITH NO EFFECTIVE TREATMENT OPTIONS. UNDERSTANDING THE PATHOLOGICAL PROCESSES AT PLAY WILL DIRECT THE APPLICATION OF NOVEL THERAPEUTIC AVENUES. HYPOXIA HAS BEEN IMPLICATED IN THE PATHOGENESIS OF PULMONARY FIBROSIS YET THE PRECISE MECHANISM BY WHICH IT CONTRIBUTES TO DISEASE PROGRESSION REMAINS TO BE FULLY ELUCIDATED. IT HAS BEEN SHOWN THAT CHRONIC HYPOXIA CAN ALTER DNA METHYLATION PATTERNS IN TUMOUR-DERIVED CELL LINES. THIS EPIGENETIC ALTERATION CAN INDUCE CHANGES IN CELLULAR PHENOTYPE WITH PROMOTER METHYLATION BEING ASSOCIATED WITH GENE SILENCING. OF PARTICULAR RELEVANCE TO IDIOPATHIC PULMONARY FIBROSIS (IPF) IS THE OBSERVATION THAT THY-1 PROMOTER METHYLATION IS ASSOCIATED WITH A MYOFIBROBLAST PHENOTYPE WHERE LOSS OF THY-1 OCCURS ALONGSIDE INCREASED ALPHA SMOOTH MUSCLE ACTIN (ALPHA-SMA) EXPRESSION. THE INITIAL AIM OF THIS STUDY WAS TO DETERMINE WHETHER HYPOXIA REGULATES DNA METHYLATION IN NORMAL HUMAN LUNG FIBROBLASTS (CCD19LU). AS IT HAS BEEN REPORTED THAT HYPOXIA SUPPRESSES THY-1 EXPRESSION DURING LUNG DEVELOPMENT WE ALSO STUDIED THE EFFECT OF HYPOXIA ON THY-1 PROMOTER METHYLATION AND GENE EXPRESSION. METHODS: CCD19LU WERE GROWN FOR UP TO 8 DAYS IN HYPOXIA AND ASSESSED FOR GLOBAL CHANGES IN DNA METHYLATION USING FLOW CYTOMETRY. REAL-TIME PCR WAS USED TO QUANTIFY EXPRESSION OF THY-1, ALPHA-SMA, COLLAGEN I AND III. GENOMIC DNA WAS BISULPHITE TREATED AND METHYLATION SPECIFIC PCR (MSPCR) WAS USED TO EXAMINE THE METHYLATION STATUS OF THE THY-1 PROMOTER. RESULTS: SIGNIFICANT GLOBAL HYPERMETHYLATION WAS DETECTED IN HYPOXIC FIBROBLASTS RELATIVE TO NORMOXIC CONTROLS AND WAS ACCOMPANIED BY INCREASED EXPRESSION OF MYOFIBROBLAST MARKERS. THY-1 MRNA EXPRESSION WAS SUPPRESSED IN HYPOXIC CELLS, WHICH WAS RESTORED WITH THE DEMETHYLATING AGENT 5-AZA-2'-DEOXYCYTIDINE. MSPCR REVEALED THAT THY-1 BECAME METHYLATED FOLLOWING FIBROBLAST EXPOSURE TO 1% O2. CONCLUSION: THESE DATA SUGGEST THAT GLOBAL AND GENE-SPECIFIC CHANGES IN DNA METHYLATION MAY PLAY AN IMPORTANT ROLE IN FIBROBLAST FUNCTION IN HYPOXIA. 2012 10 1117 33 COMPARATIVE AND EXPERIMENTAL STUDIES ON THE GENES ALTERED BY CHRONIC HYPOXIA IN HUMAN BRAIN MICROENDOTHELIAL CELLS. BACKGROUND : HYPOXIA INDUCIBLE FACTOR 1 ALPHA (HIF1A) IS A MASTER REGULATOR OF ACUTE HYPOXIA; HOWEVER, WITH CHRONIC HYPOXIA, HIF1A LEVELS RETURN TO THE NORMOXIC LEVELS. IMPORTANTLY, THE GENES THAT ARE INVOLVED IN THE CELL SURVIVAL AND VIABILITY UNDER CHRONIC HYPOXIA ARE NOT KNOWN. THEREFORE, WE TESTED THE HYPOTHESIS THAT CHRONIC HYPOXIA LEADS TO THE UPREGULATION OF A CORE GROUP OF GENES WITH ASSOCIATED CHANGES IN THE PROMOTER DNA METHYLATION THAT MEDIATES THE CELL SURVIVAL UNDER HYPOXIA. RESULTS : WE EXAMINED THE EFFECT OF CHRONIC HYPOXIA (3 DAYS; 0.5% OXYGEN) ON HUMAN BRAIN MICRO ENDOTHELIAL CELLS (HBMEC) VIABILITY AND APOPTOSIS. HYPOXIA CAUSED A SIGNIFICANT REDUCTION IN CELL VIABILITY AND AN INCREASE IN APOPTOSIS. NEXT, WE EXAMINED CHRONIC HYPOXIA ASSOCIATED CHANGES IN TRANSCRIPTOME AND GENOME-WIDE PROMOTER METHYLATION. THE DATA OBTAINED WAS COMPARED WITH 16 OTHER MICROARRAY STUDIES ON CHRONIC HYPOXIA. NINE GENES WERE ALTERED IN RESPONSE TO CHRONIC HYPOXIA IN ALL 17 STUDIES. INTERESTINGLY, HIF1A WAS NOT ALTERED WITH CHRONIC HYPOXIA IN ANY OF THE STUDIES. FURTHERMORE, WE COMPARED OUR DATA TO THREE OTHER STUDIES THAT IDENTIFIED HIF-RESPONSIVE GENES BY VARIOUS APPROACHES. ONLY TWO GENES WERE FOUND TO BE HIF DEPENDENT. WE SILENCED EACH OF THESE 9 GENES USING CRISPR/CAS9 SYSTEM. DOWNREGULATION OF EGLN3 SIGNIFICANTLY INCREASED THE CELL DEATH UNDER CHRONIC HYPOXIA, WHEREAS DOWNREGULATION OF ERO1L, ENO2, ADRENOMEDULLIN, AND SPAG4 REDUCED THE CELL DEATH UNDER HYPOXIA. CONCLUSIONS : WE PROVIDE A CORE GROUP OF GENES THAT REGULATES CELLULAR ACCLIMATIZATION UNDER CHRONIC HYPOXIC STRESS, AND MOST OF THEM ARE HIF INDEPENDENT. 2017 11 3527 25 IL-6 ENHANCES THE NUCLEAR TRANSLOCATION OF DNA CYTOSINE-5-METHYLTRANSFERASE 1 (DNMT1) VIA PHOSPHORYLATION OF THE NUCLEAR LOCALIZATION SEQUENCE BY THE AKT KINASE. THE EPIGENETIC PROGRAMMING OF GENOMIC DNA IS ACCOMPLISHED, IN PART, BY SEVERAL DNA CYTOSINE-5-METHYLTRANSFERASES THAT ACT BY COVALENTLY MODIFYING CYTOSINES WITH THE ADDITION OF A METHYL GROUP. THIS COVALENT MODIFICATION IS MAINTAINED BY THE DNA CYTOSINE-5-METHYLTRANSFERASE-1 ENZYME (DNMT1), WHICH IS CAPABLE OF ACTING IN CONCERT WITH OTHER SIMILAR ENZYMES TO SILENCE IMPORTANT TUMOR SUPPRESSOR GENES. IL-6 IS A MULTIFUNCTIONAL MEDIATOR OF INFLAMMATION, ACTING THROUGH SEVERAL MAJOR SIGNALING CASCADES, INCLUDING THE PHOSPHATIDYLINOSITOL-3-KINASE PATHWAY (PI-3-K), WHICH ACTIVATES PROTEIN KINASE B (AKT/PKB) DOWNSTREAM. HERE, WE SHOW THAT THE SUBCELLULAR LOCALIZATION OF DNMT1 CAN BE ALTERED BY THE ADDITION OF IL-6, INCREASING THE RATE OF NUCLEAR TRANSLOCATION OF THE ENZYME FROM THE CYTOSOLIC COMPARTMENT. THE MECHANISM OF NUCLEAR TRANSLOCATION OF DNMT1 IS GREATLY ENHANCED BY PHOSPHORYLATION OF THE DNMT1 NUCLEAR LOCALIZATION SIGNAL (NLS) BY PKB/AKT KINASE. MUTAGENIC ALTERATION OF THE TWO AKT TARGET AMINO ACIDS WITHIN THE NLS RESULTS IN A MAJOR LOSS OF DNMT1 NUCLEAR TRANSLOCATION, WHILE THE CREATION OF A "PHOSPHO-MIMIC" AMINO ACID (MUTATION TO ACIDIC RESIDUES) RESTORES THIS COMPARTMENTATION ABILITY. THESE OBSERVATIONS SUGGEST AN INTERESTING HYPOTHESIS REGARDING HOW MEDIATORS OF CHRONIC INFLAMMATION MAY DISTURB THE DELICATE BALANCE OF CELLULAR COMPARTMENTALIZATION OF IMPORTANT PROTEINS, AND REVEALS A POTENTIAL MECHANISM FOR THE INDUCTION OR ENHANCEMENT OF TUMOR GROWTH VIA ALTERATION OF THE COMPONENTS INVOLVED IN THE EPIGENETIC PROGRAMMING OF A CELL. 2007 12 2247 29 EPIGENETIC MODULATION OF MACROPHAGE POLARIZATION PREVENTS LUMBAR DISC DEGENERATION. INFLAMMATION PLAYS AN ESSENTIAL ROLE IN THE DEVELOPMENT OF LUMBAR DISC DEGENERATION (LDD), ALTHOUGH THE EXACT EFFECTS OF MACROPHAGE SUBTYPES ON LDD REMAIN UNCLEAR. BASED ON PREVIOUS STUDIES, WE HYPOTHESIZED THAT M2-POLARIZATION OF LOCAL MACROPHAGES AND SIMULTANEOUS SUPPRESSION OF THEIR PRODUCTION OF FIBROTIC TRANSFORMING GROWTH FACTOR BETA 1 (TGFBETA1) COULD INHIBIT PROGRESSION OF LDD. THUS, WE APPLIED AN ORTHOTOPIC INJECTION OF ADENO-ASSOCIATED VIRUS (AAV) CARRYING SHRNA FOR DNA METHYLTRANSFERASE 1 (DNMT1) AND/OR SHRNA FOR TGFBETA1 UNDER A MACROPHAGE-SPECIFIC CD68 PROMOTER TO SPECIFICALLY TARGET LOCAL MACROPHAGES IN A MOUSE MODEL FOR LDD. WE FOUND THAT SHDNMT1 SIGNIFICANTLY REDUCED LEVELS OF THE PRO-INFLAMMATORY CYTOKINES TNFALPHA, IL-1BETA AND IL-6, SIGNIFICANTLY INCREASED LEVELS OF THE ANTI-INFLAMMATORY CYTOKINES IL-4 AND IL-10, SIGNIFICANTLY INCREASED M2 MACROPHAGE POLARIZATION, SIGNIFICANTLY REDUCED CELL APOPTOSIS IN THE DISC DEGENERATION ZONE AND SIGNIFICANTLY REDUCED LDD-ASSOCIATED PAIN. THE ANTI-APOPTOTIC AND ANTI-PAIN EFFECTS WERE FURTHER STRENGTHENED BY CO-APPLICATION OF SHTGFBETA1. TOGETHER, THESE DATA SUGGEST THAT M2 POLARIZATION OF MACROPHAGES INDUCED BY BOTH EPIGENETIC MODULATION AND SUPPRESSED PRODUCTION AND RELEASE OF TGFBETA1 FROM POLARIZED M2 MACROPHAGES, MAY HAVE A DEMONSTRABLE THERAPEUTIC EFFECT ON LDD. 2020 13 2395 33 EPIGENETIC REPROGRAMMING IN MIST1(-/-) MICE PREDICTS THE MOLECULAR RESPONSE TO CERULEIN-INDUCED PANCREATITIS. GENE EXPRESSION IS AFFECTED BY MODIFICATIONS TO HISTONE CORE PROTEINS WITHIN CHROMATIN. CHANGES IN THESE MODIFICATIONS, OR EPIGENETIC REPROGRAMMING, CAN DICTATE CELL FATE AND PROMOTE SUSCEPTIBILITY TO DISEASE. THE GOAL OF THIS STUDY WAS TO DETERMINE THE EXTENT OF EPIGENETIC REPROGRAMMING IN RESPONSE TO CHRONIC STRESS THAT OCCURS FOLLOWING ABLATION OF MIST1 (MIST1(-/-) ), WHICH IS REPRESSED IN PANCREATIC DISEASE. CHROMATIN IMMUNOPRECIPITATION FOR TRIMETHYLATION OF LYSINE RESIDUE 4 ON HISTONE 3 (H3K4ME3) IN PURIFIED ACINAR CELLS FROM WILD TYPE AND MIST1(-/-) MICE WAS FOLLOWED BY NEXT GENERATION SEQUENCING (CHIP-SEQ) OR CHIP-QPCR. H3K4ME3-ENRICHED GENES WERE ASSESSED FOR EXPRESSION BY QRT-PCR IN PANCREATIC TISSUE BEFORE AND AFTER INDUCTION OF CERULEIN-INDUCED PANCREATITIS. WHILE MOST OF H3K4ME3-ENRICHMENT IS RESTRICTED TO TRANSCRIPTIONAL START SITES, >25% OF ENRICHMENT SITES ARE FOUND WITHIN, DOWNSTREAM OR BETWEEN ANNOTATED GENES. LESS THAN 10% OF THESE SITES WERE ALTERED IN MIST1(-/-) ACINI, WITH MOST CHANGES IN H3K4ME3 ENRICHMENT NOT REFLECTING ALTERED GENE EXPRESSION. INGENUITY PATHWAY ANALYSIS OF GENES DIFFERENTIALLY-ENRICHED FOR H3K4ME3 REVEALED AN ASSOCIATION WITH PANCREATITIS AND PANCREATIC DUCTAL ADENOCARCINOMA IN MIST1(-/-) TISSUE. MOST OF THESE GENES WERE NOT DIFFERENTIALLY EXPRESSED BUT SEVERAL WERE READILY INDUCED BY ACUTE EXPERIMENTAL PANCREATITIS, WITH SIGNIFICANTLY INCREASED EXPRESSION IN MIST1(-/-) TISSUE RELATIVE TO WILD TYPE MICE. WE SUGGEST THAT THE CHRONIC CELL STRESS OBSERVED IN THE ABSENCE OF MIST1 RESULTS IN EPIGENETIC REPROGRAMMING OF GENES INVOLVED IN PROMOTING PANCREATITIS TO A POISED STATE, THEREBY INCREASING THE SENSITIVITY TO EVENTS THAT PROMOTE DISEASE. 2014 14 5796 39 STAT3 PROMOTES A YOUTHFUL EPIGENETIC STATE IN ARTICULAR CHONDROCYTES. EPIGENETIC MECHANISMS GUIDING ARTICULAR CARTILAGE REGENERATION AND AGE-RELATED DISEASE SUCH AS OSTEOARTHRITIS (OA) ARE POORLY UNDERSTOOD. STAT3 IS A CRITICAL AGE-PATTERNED TRANSCRIPTION FACTOR HIGHLY ACTIVE IN FETAL AND OA CHONDROCYTES, BUT THE CONTEXT-SPECIFIC ROLE OF STAT3 IN REGULATING THE EPIGENOME OF CARTILAGE CELLS REMAIN ELUSIVE. IN THIS STUDY, DNA METHYLATION PROFILING WAS PERFORMED ACROSS HUMAN CHONDROCYTE ONTOGENY TO BUILD AN EPIGENETIC CLOCK AND ESTABLISH AN ASSOCIATION BETWEEN CPG METHYLATION AND HUMAN CHONDROCYTE AGE. EXPOSURE OF ADULT CHONDROCYTES TO A SMALL MOLECULE STAT3 AGONIST DECREASED DNA METHYLATION, WHILE GENETIC ABLATION OF STAT3 IN FETAL CHONDROCYTES INDUCED GLOBAL HYPERMETHYLATION. CUT&RUN ASSAY AND SUBSEQUENT TRANSCRIPTIONAL VALIDATION REVEALED DNA METHYLTRANSFERASE 3 BETA (DNMT3B) AS ONE OF THE PUTATIVE STAT3 TARGETS IN CHONDROCYTE DEVELOPMENT AND OA. FUNCTIONAL ASSESSMENT OF HUMAN OA CHONDROCYTES SHOWED THE ACQUISITION OF PROGENITOR-LIKE IMMATURE PHENOTYPE BY A SIGNIFICANT SUBSET OF CELLS. FINALLY, CONDITIONAL DELETION OF STAT3 IN CARTILAGE CELLS INCREASED DNMT3B EXPRESSION IN ARTICULAR CHONDROCYTES IN THE KNEE JOINT IN VIVO AND RESULTED IN A MORE PROMINENT OA PROGRESSION IN A POST-TRAUMATIC OA (PTOA) MOUSE MODEL INDUCED BY DESTABILIZATION OF THE MEDIAL MENISCUS (DMM). TAKEN TOGETHER THESE DATA REVEAL A NOVEL ROLE FOR STAT3 IN REGULATING DNA METHYLATION IN CARTILAGE DEVELOPMENT AND DISEASE. OUR FINDINGS ALSO SUGGEST THAT ELEVATED LEVELS OF ACTIVE STAT3 IN OA CHONDROCYTES MAY INDICATE AN INTRINSIC ATTEMPT OF THE TISSUE TO REGENERATE BY PROMOTING A PROGENITOR-LIKE PHENOTYPE. HOWEVER, IT IS LIKELY THAT CHRONIC ACTIVATION OF THIS PATHWAY, INDUCED BY IL-6 CYTOKINES, IS DETRIMENTAL AND LEADS TO TISSUE DEGENERATION. 2023 15 3658 28 INDUCTION OF ABERRANT TRIMETHYLATION OF HISTONE H3 LYSINE 27 BY INFLAMMATION IN MOUSE COLONIC EPITHELIAL CELLS. A FIELD FOR CANCERIZATION (FIELD DEFECT), WHERE GENETIC AND EPIGENETIC ALTERATIONS ARE ACCUMULATED IN NORMAL-APPEARING TISSUES, IS INVOLVED IN HUMAN CARCINOGENESIS, ESPECIALLY CANCERS ASSOCIATED WITH CHRONIC INFLAMMATION. ALTHOUGH ABERRANT DNA METHYLATION IS INVOLVED IN THE FIELD DEFECT AND INDUCED BY CHRONIC INFLAMMATION, IT IS STILL UNCLEAR FOR TRIMETHYLATION OF HISTONE H3 LYSINE 27 (H3K27ME3), WHICH IS INVOLVED IN GENE REPRESSION INDEPENDENT OF DNA METHYLATION AND FUNCTIONS AS A PRE-MARK FOR ABERRANT DNA METHYLATION. IN THIS STUDY, USING A MOUSE COLITIS MODEL INDUCED BY DEXTRAN SULFATE SODIUM (DSS), WE AIMED TO CLARIFY WHETHER ABERRANT H3K27ME3 IS INDUCED BY INFLAMMATION AND INVOLVED IN A FIELD DEFECT. CHIP-ON-CHIP ANALYSIS OF COLONIC EPITHELIAL CELLS REVEALED THAT H3K27ME3 LEVELS WERE INCREASED OR DECREASED FOR 266 GENOMIC REGIONS BY AGING, AND MORE EXTENSIVELY (23 INCREASED AND 3574 DECREASED REGIONS) BY COLITIS. SUCH INCREASE OR DECREASE OF H3K27ME3 WAS INDUCED AS EARLY AS 2 WEEKS AFTER THE INITIATION OF DSS TREATMENT, AND PERSISTED AT LEAST FOR 16 WEEKS EVEN AFTER THE INFLAMMATION DISAPPEARED. SOME OF THE ABERRANT H3K27ME3 IN COLONIC EPITHELIAL CELLS WAS CARRIED OVER INTO COLON TUMORS. FURTHERMORE, H3K27ME3 ACQUIRED AT DAPK1 BY COLITIS WAS FOLLOWED BY INCREASED DNA METHYLATION, SUPPORTING ITS FUNCTION AS A PRE-MARK FOR ABERRANT DNA METHYLATION. THESE RESULTS DEMONSTRATED THAT ABERRANT H3K27ME3 CAN BE INDUCED BY EXPOSURE TO A SPECIFIC ENVIRONMENT, SUCH AS COLITIS, AND SUGGESTED THAT ABERRANT HISTONE MODIFICATION, IN ADDITION TO ABERRANT DNA METHYLATION, IS INVOLVED IN THE FORMATION OF A FIELD DEFECT. 2012 16 6419 37 THE TET2-UPF1 COMPLEX MODULATES MRNA STABILITY UNDER STRESS CONDITIONS. INTRODUCTION: ENVIRONMENTAL STRESS PROMOTES EPIGENETIC ALTERATIONS THAT IMPACT GENE EXPRESSION AND SUBSEQUENTLY PARTICIPATE IN THE PATHOLOGICAL PROCESSES OF THE DISORDER. AMONG EPIGENETIC REGULATIONS, TEN-ELEVEN TRANSLOCATION (TET) ENZYMES OXIDIZE 5-METHYLCYTOSINE (5MC) TO 5-HYDROXYMETHYLCYTOSINE (5HMC) IN DNA AND RNA AND FUNCTION AS CRITICAL PLAYERS IN THE PATHOGENESIS OF DISEASES. OUR PREVIOUS RESULTS SHOWED THAT CHRONIC STRESS INCREASES THE EXPRESSION OF CYTOPLASMIC TET2 IN THE HIPPOCAMPUS OF MICE EXPOSED TO CHRONIC MILD STRESS (CMS). WHETHER THE CYTOPLASMIC TET2 ALTERS RNA 5HMC MODIFICATION IN CHRONIC STRESS-RELATED PROCESSES REMAINS LARGELY UNKNOWN. METHODS: TO EXPLORE THE ROLE OF CYTOPLASMIC TET2 UNDER CMS CONDITIONS, WE ESTABLISHED CMS MICE MODEL AND DETECTED THE EXPRESSION OF RNA 5HMC BY DOT BLOT. WE VERIFIED THE INTERACTION OF TET2 AND ITS INTERACTING PROTEIN BY CO-IMMUNOPRECIPITATION COMBINED WITH MASS SPECTROMETRY AND SCREENED DOWNSTREAM TARGET GENES BY CLUSTER ANALYSIS OF TET2 AND UPSTREAM FRAMESHIFT 1 (UPF1) INTERACTING RNA. THE EXPRESSION OF PROTEIN WAS DETECTED BY WESTERN BLOT AND THE EXPRESSION OF THE SCREENED TARGET GENES WAS DETECTED BY QRT-PCR. RESULTS: IN THIS STUDY, WE FOUND THAT INCREASED CYTOPLASMIC TET2 EXPRESSION UNDER CMS CONDITIONS LEADS TO INCREASE IN TOTAL RNA 5HMC MODIFICATION. TET2 INTERACTED WITH THE KEY NON-SENSE-MEDIATED MRNA DECAY (NMD) FACTOR UPF1, REGULATED THE STABILITY OF STRESS-RELATED GENES SUCH AS UNC5B MRNA, AND MIGHT THEREBY AFFECT NEURODEVELOPMENT. DISCUSSION: IN SUMMARY, THIS STUDY REVEALED THAT TET2-MEDIATED RNA 5HMC MODIFICATION IS INVOLVED IN STRESS-RELATED MRNA STABILITY REGULATION AND MAY SERVE AS A POTENTIAL THERAPEUTIC TARGET FOR CHRONIC STRESS-RELATED DISEASES SUCH AS DEPRESSION. 2023 17 2297 29 EPIGENETIC REGULATION OF ACUTE INFLAMMATORY PAIN. ACUTE PAIN IS ASSOCIATED WITH TISSUE DAMAGE, WHICH RESULTS IN THE RELEASE OF INFLAMMATORY MEDIATORS. RECENT STUDIES POINT TO THE INVOLVEMENT OF EPIGENETIC MECHANISMS (DNA METHYLATION) IN THE DEVELOPMENT OF PAIN. WE HAVE FOUND THAT DURING ACUTE INFLAMMATORY PAIN INDUCED BY THE APPLICATION OF 10% MUSTARD OIL ON THE TONGUES OF RATS, LEVELS OF DNMT3A AND 3B WERE ELEVATED MARKEDLY (36 AND 42 % RESPECTIVELY), WHEREAS THE LEVEL OF DNMT1 WAS NOT CHANGED SIGNIFICANTLY. PREVIOUS INJECTION OF XEFOCAM WITH 0,4 MG/KG DOSE DECREASED LEVELS OF DNMT3A AND 3B (25 AND 24% RESPECTIVELY). THE LEVEL OF DNMT1 WAS NOT CHANGED SIGNIFICANTLY COMPARED TO THE CONTROL GROUP. THE FINDINGS SUPPORT THE IDEA THAT INHIBITORS OF DNA-METHYLTRANSFERASES COULD BE USEFUL FOR PAIN MANAGEMENT. OUR DATA SUGGEST THAT NSAIDS (ALONE OR IN COMBINATION WITH DNMT INHIBITORS) MAY BE PROPOSED AS POSSIBLE EPIGENETIC REGULATORY AGENTS, WHICH MAY PLAY A ROLE IN EPIGENETIC MECHANISMS INDIRECTLY THROUGH ALTERING THE ACTIVITY OF INFLAMMATORY MEDIATORS INVOLVED IN PAIN DEVELOPMENT. 2014 18 4159 30 MECP2 CONTROLS AN EPIGENETIC PATHWAY THAT PROMOTES MYOFIBROBLAST TRANSDIFFERENTIATION AND FIBROSIS. BACKGROUND & AIMS: MYOFIBROBLAST TRANSDIFFERENTIATION GENERATES HEPATIC MYOFIBROBLASTS, WHICH PROMOTE LIVER FIBROGENESIS. THE PEROXISOME PROLIFERATOR-ACTIVATED RECEPTOR GAMMA (PPARGAMMA) IS A NEGATIVE REGULATOR OF THIS PROCESS. WE INVESTIGATED EPIGENETIC REGULATION OF PPARGAMMA AND MYOFIBROBLAST TRANSDIFFERENTIATION. METHODS: CHROMATIN IMMUNOPRECIPITATION (CHIP) ASSAYS ASSESSED THE BINDING OF METHYL-CPG BINDING PROTEIN 2 (MECP2) TO PPARGAMMA AND CHROMATIN MODIFICATIONS THAT SILENCE THIS GENE. MECP2(-/Y) MICE AND AN INHIBITOR (DZNEP) OF THE EPIGENETIC REGULATORY PROTEIN EZH2 WERE USED IN THE CARBON TETRACHLORIDE MODEL OF LIVER FIBROSIS. LIVER TISSUES FROM MICE WERE ASSESSED BY HISTOLOGIC ANALYSIS; MARKERS OF FIBROSIS WERE MEASURED BY QUANTITATIVE POLYMERASE CHAIN REACTION (QPCR). REVERSE TRANSCRIPTION PCR DETECTED CHANGES IN EXPRESSION OF THE MICRORNA MIR132 AND ITS TARGET, ELONGATED TRANSCRIPTS OF MECP2. MYOFIBROBLASTS WERE TRANSFECTED WITH MIR132; PPARGAMMA AND MECP2 EXPRESSIONS WERE ANALYZED BY QPCR OR IMMUNOBLOTTING. RESULTS: MYOFIBROBLAST TRANSDIFFERENTIATION OF HEPATIC STELLATE CELLS IS CONTROLLED BY A COMBINATION OF MECP2, EZH2, AND MIR132 IN A RELAY PATHWAY. THE PATHWAY IS ACTIVATED BY DOWN-REGULATION OF MIR132, RELEASING THE TRANSLATIONAL BLOCK ON MECP2. MECP2 IS RECRUITED TO THE 5' END OF PPARGAMMA, WHERE IT PROMOTES METHYLATION BY H3K9 AND RECRUITS THE TRANSCRIPTION REPRESSOR HP1ALPHA. MECP2 ALSO STIMULATES EXPRESSION OF EZH2 AND METHYLATION OF H3K27 TO FORM A REPRESSIVE CHROMATIN STRUCTURE IN THE 3' EXONS OF PPARGAMMA. GENETIC AND PHARMACOLOGIC DISRUPTIONS OF MECP2 OR EZH2 REDUCED THE FIBROGENIC CHARACTERISTICS OF MYOFIBROBLASTS AND ATTENUATED FIBROGENESIS. CONCLUSIONS: LIVER FIBROSIS IS REGULATED BY AN EPIGENETIC RELAY PATHWAY THAT INCLUDES MECP2, EZH2, AND MIR132. REAGENTS THAT INTERFERE WITH THIS PATHWAY MIGHT BE DEVELOPED TO REDUCE FIBROGENESIS IN CHRONIC LIVER DISEASE. 2010 19 3473 33 IDENTIFICATION OF A NOVEL, METHYLATION-DEPENDENT, RUNX2 REGULATORY REGION ASSOCIATED WITH OSTEOARTHRITIS RISK. OSTEOARTHRITIS (OA) IS A COMMON, MULTIFACTORIAL AND POLYGENIC SKELETAL DISEASE THAT, IN ITS SEVEREST FORM, REQUIRES JOINT REPLACEMENT SURGERY TO RESTORE MOBILITY AND TO RELIEVE CHRONIC PAIN. USING TISSUES FROM THE ARTICULATING JOINTS OF 260 PATIENTS WITH OA AND A RANGE OF IN VITRO EXPERIMENTS, INCLUDING CRISPR-CAS9, WE HAVE CHARACTERIZED AN INTERGENIC REGULATORY ELEMENT. HERE, GENOTYPE AT AN OA RISK LOCUS CORRELATES WITH DIFFERENTIAL DNA METHYLATION, WITH ALTERED GENE EXPRESSION OF BOTH A TRANSCRIPTIONAL REGULATOR (RUNX2), AND A CHROMATIN REMODELLING PROTEIN (SUPT3H). RUNX2 IS A STRONG CANDIDATE FOR OA SUSCEPTIBILITY, WITH ITS ENCODED PROTEIN BEING ESSENTIAL FOR SKELETOGENESIS AND HEALTHY JOINT FUNCTION. THE OA RISK LOCUS INCLUDES SINGLE NUCLEOTIDE POLYMORPHISMS (SNPS) LOCATED WITHIN AND FLANKING THE DIFFERENTIALLY METHYLATED REGION (DMR). THE OA ASSOCIATION SNP, RS10948172, DEMONSTRATES PARTICULARLY STRONG CORRELATION WITH METHYLATION, AND TWO INTERGENIC SNPS FALLING WITHIN THE DMR (RS62435998 AND RS62435999) DEMONSTRATE GENETIC AND EPIGENETIC EFFECTS ON THE REGULATORY ACTIVITY OF THIS REGION. WE THEREFORE POSIT THAT THE OA SIGNAL MEDIATES ITS EFFECT BY MODULATING THE METHYLATION OF THE REGULATORY ELEMENT, WHICH THEN IMPACTS ON GENE EXPRESSION, WITH RUNX2 BEING THE PRINCIPAL TARGET. OUR STUDY HIGHLIGHTS THE INTERPLAY BETWEEN DNA METHYLATION, OA GENETIC RISK AND THE DOWNSTREAM REGULATION OF GENES CRITICAL TO NORMAL JOINT FUNCTION. 2018 20 4742 27 NOVEL HISTONE MODIFICATIONS IN MICROGLIA DERIVED FROM A MOUSE MODEL OF CHRONIC PAIN. AS THE RESIDENT IMMUNE CELLS IN THE CENTRAL NERVOUS SYSTEM, MICROGLIA PLAY AN IMPORTANT ROLE IN THE MAINTENANCE OF ITS HOMEOSTASIS. DYSREGULATION OF MICROGLIA HAS BEEN ASSOCIATED WITH THE DEVELOPMENT AND MAINTENANCE OF CHRONIC PAIN. HOWEVER, THE RELEVANT MOLECULAR PATHWAYS REMAIN POORLY DEFINED. IN THIS STUDY, WE USED A MASS SPECTROMETRY-BASED PROTEOMIC APPROACH TO SCREEN POTENTIAL CHANGES OF HISTONE PROTEIN MODIFICATIONS IN MICROGLIA ISOLATED FROM THE BRAIN OF CONTROL AND CISPLATIN-INDUCED NEUROPATHIC PAIN ADULT C57BL/6J MALE MICE. WE IDENTIFIED SEVERAL NOVEL MICROGLIAL HISTONE MODIFICATIONS ASSOCIATED WITH PAIN, INCLUDING STATISTICALLY SIGNIFICANTLY DECREASED HISTONE H3.1 LYSINE 27 MONO-METHYLATION (H3.1K27ME1, 54.8% OF CONTROL) AND H3 LYSINE 56 TRI-METHYLATION (7.5% OF CONTROL), AS WELL AS A TREND SUGGESTING INCREASED H3 TYROSINE 41 NITRATION. WE FURTHER INVESTIGATED THE FUNCTIONAL ROLE OF H3.1K27ME1 AND FOUND THAT TREATMENT OF CULTURED MICROGLIAL CELLS FOR 4 CONSECUTIVE DAYS WITH 1-10 MUM OF NCDM-64, A POTENT AND SELECTIVE INHIBITOR OF LYSINE DEMETHYLASE 7A, AN ENZYME RESPONSIBLE FOR THE DEMETHYLATION OF H3K27ME1, DOSE-DEPENDENTLY ELEVATED ITS LEVELS WITH A GREATER THAN A TWO-FOLD INCREASE OBSERVED AT 10 MUM COMPARED TO VEHICLE-TREATED CONTROL CELLS. MOREOVER, PRETREATMENT OF MICE WITH NCDM-64 (10 OR 25 MG/KG/DAY, I.P.) PRIOR TO CISPLATIN TREATMENT PREVENTED THE DEVELOPMENT OF NEUROPATHIC PAIN IN MICE. THE IDENTIFICATION OF SPECIFIC CHROMATIN MARKS IN MICROGLIA ASSOCIATED WITH CHRONIC PAIN MAY YIELD CRITICAL INSIGHT INTO THE CONTRIBUTION OF MICROGLIA TO THE DEVELOPMENT AND MAINTENANCE OF PAIN, AND OPENS NEW AVENUES FOR THE DEVELOPMENT OF NOVEL NONOPIOID THERAPEUTICS FOR THE EFFECTIVE MANAGEMENT OF CHRONIC PAIN. 2022