1 5459 127 RESEARCH ON THE EPIGENETIC REGULATION MECHANISM OF THE PTPN6 GENE IN ADVANCED CHRONIC MYELOID LEUKAEMIA. PTPN6, A TYROSINE PHOSPHATASE PROTEIN, PLAYS A NEGATIVE ROLE IN CELL SIGNAL TRANSDUCTION AND IS NEGATIVELY CORRELATED WITH TUMOUR FORMATION AND GROWTH. HOWEVER, EPIGENETIC REGULATION MECHANISM OF THE PTPN6 GENE IN ADVANCED CHRONIC MYELOID LEUKAEMIA (CML) REMAINS UNCLEAR. THIS STUDY INVESTIGATED BONE MARROW OR BLOOD SAMPLES FROM 44 CML PATIENTS AND 10 HEALTHY VOLUNTEERS. KCL22 AND K562 CELLS WERE CULTURED AND TREATED WITH DEMETHYLATION DRUGS AND HISTONE DEACETYLASE INHIBITORS. REAL TIME QUANTITATIVE POLYMERASE CHAIN REACTION (QPCR), METHYLATION-SPECIFIC PCR, BISULFITE SEQUENCING PCR, WESTERN BLOTTING, CO-IMMUNOPRECIPITATION AND CHROMATIN IMMUNOPRECIPITATION (CHIP) WAS PERFORMED. PTPN6 WAS DOWN-REGULATED IN CELL LINES AND PATIENTS WITH ADVANCED PHASE CML, WHEREAS DNMT1, DNMT3A, MECP2, MBD2 AND HDAC1 WERE UP-REGULATED. TREATMENT WITH 5-AZACYTIDINE, DECITABINE, SODIUM VALPROATE AND LBH589 INCREASED PTPN6 EXPRESSION, BUT DECREASED THAT OF DNMT1, DNMT3A, MECP2, MBD2 AND HDAC1. IMMUNOPRECIPITATION AND MASS SPECTROMETRY SHOWED THAT HDAC1 COMBINED DIRECTLY WITH PTPN6. CHIP-SEQ SHOWED THAT HDAC1 DID NOT COMBINE WITH THE PROMOTER REGION OF PTPN6, WHILE MAPK, AKT, STAT5, JAK2 AND MYC PROMOTER REGIONS ALL COMBINED WITH HDAC1. PTPN6 IS ASSOCIATED WITH PROGRESSION OF CML. LOW EXPRESSION LEVEL OF PTPN6 WAS ASSOCIATED WITH DNA METHYLATION AND REGULATED BY HISTONE ACETYLATION. HDAC1 PARTICIPATES IN THE REGULATION OF PTPN6. 2017 2 2326 61 EPIGENETIC REGULATION OF HOTAIR IN ADVANCED CHRONIC MYELOID LEUKEMIA. PURPOSE: CHRONIC MYELOID LEUKEMIA (CML) ACCOUNTS FOR ~10% OF LEUKEMIA CASES, AND ITS PROGRESSION INVOLVES EPIGENETIC GENE REGULATION. THIS STUDY INVESTIGATED EPIGENETIC REGULATION OF HOTAIR AND ITS TARGET MICRORNA, MIR-143, IN ADVANCED CML. PATIENTS AND METHODS: WE FIRST ISOLATED BONE MARROW MONONUCLEAR CELLS FROM 70 PATIENTS WITH DIFFERENT PHASES OF CML AND FROM HEALTHY DONORS AS NORMAL CONTROL; WE ALSO CULTURED K562 AND KCL22 CELLS, TREATED WITH DEMETHYLATION DRUG; MTT ASSAY, FLOW CYTOMETRY, QUANTITATIVE REAL-TIME POLYMERASE CHAIN REACTION (QPCR), METHYLATION-SPECIFIC POLYMERASE CHAIN REACTION (MSP), WESTERN BLOT, LUCIFERASE ASSAY, RNA PULL-DOWN ASSAY AND RNA-BINDING PROTEIN IMMUNOPRECIPITATION (RIP) ASSAY WERE PERFORMED. RESULT: AS MEASURED BY QPCR, HOTAIR EXPRESSION IN K562 CELLS, KCL22 CELLS, AND SAMPLES FROM CASES OF ADVANCED-STAGE CML INCREASED WITH LEVELS OF SEVERAL DNA METHYLTRANSFERASES AND HISTONE DEACETYLATES, INCLUDING DNMT1, DNMT3A, HDAC1, EZH2, AND LSD1, AND MIR-143 LEVELS WERE DECREASED AND HOTAIR LEVELS WERE INCREASED. TREATMENT WITH 5-AZACYTIDINE, A DNA METHYLATION INHIBITOR, DECREASED DNMT1, DNMT3A, HDAC1, EZH2, LSD1 MRNA, PROTEIN LEVELS, AND HOTAIR MRNA LEVELS BUT INCREASED MIR-143 LEVELS. HOTAIR KNOCKDOWN AND MIR-143 OVEREXPRESSION BOTH INHIBITED PROLIFERATION AND PROMOTED APOPTOSIS IN KCL22 AND K562 CELLS THROUGH THE PI3K/AKT PATHWAY. RNA PULL-DOWN, MASS SPECTROMETRY, AND RIP ASSAYS SHOWED THAT HOTAIR INTERACTED WITH EZH2 AND LSD1. A DUAL-LUCIFERASE ASSAY DEMONSTRATED THAT HOTAIR INTERACTED WITH MIR-143. CONCLUSION: OUR FINDINGS DEMONSTRATE THE KEY EPIGENETIC INTERACTIONS OF HOTAIR RELATED TO CML PROGRESSION AND SUGGEST HOTAIR AS A POTENTIAL THERAPEUTIC TARGET FOR ADVANCED CML. FURTHERMORE, OUR RESULTS SUPPORT THE USE OF DEMETHYLATION DRUGS AS A CML TREATMENT STRATEGY. 2018 3 2300 27 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 4 3082 37 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 5 2365 28 EPIGENETIC REGULATION OF SPINAL CXCR2 SIGNALING IN INCISIONAL HYPERSENSITIVITY IN MICE. BACKGROUND: THE REGULATION OF GENE EXPRESSION IN NOCICEPTIVE PATHWAYS CONTRIBUTES TO THE INDUCTION AND MAINTENANCE OF PAIN SENSITIZATION. HISTONE ACETYLATION IS A KEY EPIGENETIC MECHANISM CONTROLLING CHROMATIN STRUCTURE AND GENE EXPRESSION. CHEMOKINE CC MOTIF RECEPTOR 2 (CXCR2) IS A PROINFLAMMATORY RECEPTOR IMPLICATED IN NEUROPATHIC AND INFLAMMATORY PAIN AND IS KNOWN TO BE REGULATED BY HISTONE ACETYLATION IN SOME SETTINGS. THE AUTHORS SOUGHT TO INVESTIGATE THE ROLE OF HISTONE ACETYLATION ON SPINAL CXCR2 SIGNALING AFTER INCISION. METHODS: GROUPS OF 5-8 MICE UNDERWENT HIND PAW INCISION. SUBEROYLANILIDE HYDROXAMIC ACID AND ANACARDIC ACID WERE USED TO INHIBIT HISTONE DEACETYLASE AND HISTONE ACETYLTRANSFERASE, RESPECTIVELY. BEHAVIORAL MEASURES OF THERMAL AND MECHANICAL SENSITIZATION AS WELL AS HYPERALGESIC PRIMING WERE USED. BOTH MESSAGE RNA QUANTIFICATION AND CHROMATIN IMMUNOPRECIPITATION ANALYSIS WERE USED TO STUDY THE REGULATION OF CXCR2 AND LIGAND EXPRESSION. FINALLY, THE SELECTIVE CXCR2 ANTAGONIST SB225002 WAS ADMINISTERED INTRATHECALLY TO REVEAL THE FUNCTION OF SPINAL CXCR2 RECEPTORS AFTER HIND PAW INCISION. RESULTS: SUBEROYLANILIDE HYDROXAMIC ACID SIGNIFICANTLY EXACERBATED MECHANICAL SENSITIZATION AFTER INCISION. CONVERSELY, ANACARDIC ACID REDUCED INCISIONAL SENSITIZATION AND ALSO ATTENUATED INCISION-INDUCED HYPERALGESIC PRIMING. OVERALL, ACETYLATED HISTONE H3 AT LYSINE 9 WAS INCREASED IN SPINAL CORD TISSUES AFTER INCISION, AND ENHANCED ASSOCIATION OF ACETYLATED HISTONE H3 AT LYSINE 9 WITH THE PROMOTER REGIONS OF CXCR2 AND KERATINOCYTE-DERIVED CHEMOKINE (CXCL1) WAS OBSERVED AS WELL. BLOCKING CXCR2 REVERSED MECHANICAL HYPERSENSITIVITY AFTER HIND PAW INCISION. CONCLUSIONS: HISTONE MODIFICATION IS AN IMPORTANT EPIGENETIC MECHANISM REGULATING INCISION-INDUCED NOCICEPTIVE SENSITIZATION. THE SPINAL CXCR2 SIGNALING PATHWAY IS ONE EPIGENETICALLY REGULATED PATHWAY CONTROLLING EARLY AND LATENT SENSITIZATION AFTER INCISION. 2013 6 1320 30 DEMETHYLATION REGULATION OF BDNF GENE EXPRESSION IN DORSAL ROOT GANGLION NEURONS IS IMPLICATED IN OPIOID-INDUCED PAIN HYPERSENSITIVITY IN RATS. REPEATED ADMINISTRATION OF MORPHINE MAY RESULT IN OPIOID-INDUCED HYPERSENSITIVITY (OIH), WHICH INVOLVES ALTERED EXPRESSION OF NUMEROUS GENES, INCLUDING BRAIN-DERIVED NEUROTROPHIC FACTOR (BDNF) IN DORSAL ROOT GANGLION (DRG) NEURONS. YET, IT REMAINS UNCLEAR HOW BDNF EXPRESSION IS INCREASED IN DRG NEURONS AFTER REPEATED MORPHINE TREATMENT. DNA METHYLATION IS AN IMPORTANT MECHANISM OF EPIGENETIC CONTROL OF GENE EXPRESSION. IN THE CURRENT STUDY, WE HYPOTHESIZED THAT THE DEMETHYLATION REGULATION OF CERTAIN BDNF GENE PROMOTERS IN DRG NEURONS MAY CONTRIBUTE TO THE DEVELOPMENT OF OIH. REAL-TIME RT-PCR WAS USED TO ASSESS CHANGES IN THE MRNA TRANSCRIPTION LEVELS OF MAJOR BDNF EXONS INCLUDING EXON I, II, IV, VI, AS WELL AS TOTAL BDNF MRNA IN DRGS FROM RATS AFTER REPEATED MORPHINE ADMINISTRATION. THE LEVELS OF EXON IV AND TOTAL BDNF MRNA WERE SIGNIFICANTLY UPREGULATED BY REPEATED MORPHINE ADMINISTRATION, AS COMPARED TO THAT IN SALINE CONTROL GROUP. FURTHER, ELISA ARRAY AND IMMUNOCYTOCHEMISTRY STUDY REVEALED A ROBUST UPREGULATION OF BDNF PROTEIN EXPRESSION IN DRG NEURONS AFTER REPEATED MORPHINE EXPOSURE. CORRESPONDINGLY, THE METHYLATION LEVELS OF BDNF EXON IV PROMOTER SHOWED A SIGNIFICANT DOWNREGULATION BY MORPHINE TREATMENT. IMPORTANTLY, INTRATHECAL ADMINISTRATION OF A BDNF ANTIBODY, BUT NOT CONTROL IGG, SIGNIFICANTLY INHIBITED MECHANICAL HYPERSENSITIVITY THAT DEVELOPED IN RATS AFTER REPEATED MORPHINE TREATMENT. CONVERSELY, INTRATHECAL ADMINISTRATION OF AN INHIBITOR OF DNA METHYLATION, 5-AZA-2'-DEOXYCYTIDINE (5-AZA-DC) MARKEDLY UPREGULATED THE BDNF PROTEIN EXPRESSION IN DRG NEURONS AND ENHANCED THE MECHANICAL ALLODYNIA AFTER REPEATED MORPHINE EXPOSURE. TOGETHER, OUR FINDINGS SUGGEST THAT DEMETHYLATION REGULATION OF BDNF GENE PROMOTER MAY BE IMPLICATED IN THE DEVELOPMENT OF OIH THROUGH EPIGENETIC CONTROL OF BDNF EXPRESSION IN DRG NEURONS. 2016 7 717 33 CALCITONIN GENE-RELATED PEPTIDE REGULATES SPINAL MICROGLIAL ACTIVATION THROUGH THE HISTONE H3 LYSINE 27 TRIMETHYLATION VIA ENHANCER OF ZESTE HOMOLOG-2 IN RATS WITH NEUROPATHIC PAIN. BACKGROUND: CALCITONIN GENE-RELATED PEPTIDE (CGRP) AS A MEDIATOR OF MICROGLIAL ACTIVATION AT THE TRANSCRIPTIONAL LEVEL MAY FACILITATE NOCICEPTIVE SIGNALING. TRIMETHYLATION OF H3 LYSINE 27 (H3K27ME3) BY ENHANCER OF ZESTE HOMOLOG 2 (EZH2) IS AN EPIGENETIC MARK THAT REGULATES INFLAMMATORY-RELATED GENE EXPRESSION AFTER PERIPHERAL NERVE INJURY. IN THIS STUDY, WE EXPLORED THE RELATIONSHIP BETWEEN CGRP AND H3K27ME3 IN MICROGLIAL ACTIVATION AFTER NERVE INJURY, AND ELUCIDATED THE UNDERLYING MECHANISMS IN THE PATHOGENESIS OF CHRONIC NEUROPATHIC PAIN. METHODS: MICROGLIAL CELLS (BV2) WERE TREATED WITH CGRP AND DIFFERENTIALLY ENRICHMENTS OF H3K27ME3 ON GENE PROMOTERS WERE EXAMINED USING CHIP-SEQ. A CHRONIC CONSTRICTION INJURY (CCI) RAT MODEL WAS USED TO EVALUATE THE ROLE OF CGRP ON MICROGLIAL ACTIVATION AND EZH2/H3K27ME3 SIGNALING IN CCI-INDUCED NEUROPATHIC PAIN. RESULTS: OVEREXPRESSIONS OF EZH2 AND H3K27ME3 WERE CONFIRMED IN SPINAL MICROGLIA OF CCI RATS BY IMMUNOFLUORESCENCE. CGRP TREATMENT INDUCED THE INCREASED OF H3K27ME3 EXPRESSION IN THE SPINAL DORSAL HORN AND CULTURED MICROGLIAL CELLS (BV2) THROUGH EZH2. CHIP-SEQ DATA INDICATED THAT CGRP SIGNIFICANTLY ALTERED H3K27ME3 ENRICHMENTS ON GENE PROMOTERS IN MICROGLIA FOLLOWING CGRP TREATMENT, INCLUDING 173 GAINING H3K27ME3 AND 75 LOSING THIS MARK, WHICH MOSTLY ENRICHED IN REGULATION OF CELL GROWTH, PHAGOSOME, AND INFLAMMATION. QRT-PCR VERIFIED EXPRESSIONS OF REPRESENTATIVE CANDIDATE GENES (TRAF3IP2, BCL2L11, ITGAM, DAB2, NLRP12, WNT3, ADAM10) AND REAL-TIME CELL ANALYSIS (RTCA) VERIFIED MICROGLIAL PROLIFERATION. ADDITIONALLY, CGRP TREATMENT AND CCI INCREASED EXPRESSIONS OF ITGAM, ADAM10, MCP-1, AND CX3CR1, KEY MEDIATORS OF MICROGLIAL ACTIVATION IN SPINAL DORSAL HORN AND CULTURED MICROGLIAL CELLS. SUCH INCREASED EFFECTS INDUCED BY CCI WERE SUPPRESSED BY CGRP ANTAGONIST AND EZH2 INHIBITOR, WHICH WERE CONCURRENTLY ASSOCIATED WITH THE ATTENUATED MECHANICAL AND THERMAL HYPERALGESIA IN CCI RATS. CONCLUSION: OUR FINDINGS HIGHLY INDICATE THAT CGRP IS IMPLICATED IN THE GENESIS OF NEUROPATHIC PAIN THROUGH REGULATING MICROGLIAL ACTIVATION VIA EZH2-MEDIATED H3K27ME3 IN THE SPINAL DORSAL HORN. 2021 8 6660 36 UPREGULATION OF CXCR4 THROUGH PROMOTER DEMETHYLATION CONTRIBUTES TO INFLAMMATORY HYPERALGESIA IN RATS. AIM AND METHODS: CHRONIC PAIN ASSOCIATED WITH INFLAMMATION IS A COMMON CLINICAL PROBLEM, AND THE UNDERLYING MECHANISMS YET ARE INCOMPLETELY DEFINED. DNA METHYLATION HAS BEEN IMPLICATED IN THE PATHOGENESIS OF CHRONIC PAIN. HOWEVER, THE SPECIFIC GENES REGULATED BY DNA METHYLATION UNDER INFLAMMATORY PAIN CONDITION REMAIN LARGELY UNKNOWN. HERE, WE INVESTIGATED HOW CHEMOKINE RECEPTOR CXCR4 EXPRESSION IS REGULATED BY DNA METHYLATION AND HOW IT CONTRIBUTES TO INFLAMMATORY PAIN INDUCED BY COMPLETE FREUND'S ADJUVANT (CFA) IN RATS. RESULTS: INTRAPLANTAR INJECTION OF CFA COULD NOT ONLY INDUCE SIGNIFICANT HYPERALGESIA IN RATS, BUT ALSO SIGNIFICANTLY INCREASE THE EXPRESSION OF CXCR4 MRNA AND PROTEIN IN THE DORSAL ROOT GANGLION (DRG). INTRATHECAL INJECTION OF CXCR4 ANTAGONIST AMD3100 SIGNIFICANTLY RELIEVED HYPERALGESIA IN INFLAMMATORY RATS IN A TIME- AND DOSE-DEPENDENT MANNER. BISULFITE SEQUENCING AND METHYLATION-SPECIFIC PCR DEMONSTRATE THAT CFA INJECTION LED TO A SIGNIFICANT DEMETHYLATION OF CPG ISLAND AT CXCR4 GENE PROMOTER. CONSISTENTLY, THE EXPRESSION OF DNMT3B WAS SIGNIFICANTLY DOWNREGULATED AFTER CFA INJECTION. ONLINE SOFTWARE PREDICTION REVEALS THREE BINDING SITES OF P65 IN THE CPG ISLAND OF CXCR4 GENE PROMOTER, WHICH HAS CONFIRMED BY THE CHROMATIN IMMUNOPRECIPITATION ASSAY, CFA TREATMENT SIGNIFICANTLY INCREASES THE RECRUITMENT OF P65 TO CXCR4 GENE PROMOTER. INHIBITION OF NF-KB SIGNALING USING P65 INHIBITOR PYRROLIDINE DITHIOCARBAMATE SIGNIFICANTLY PREVENTED THE INCREASES OF THE CXCR4 EXPRESSION. CONCLUSION: UPREGULATION OF CXCR4 EXPRESSION DUE TO PROMOTER DEMETHYLATION FOLLOWED BY INCREASED RECRUITMENT OF P65 TO PROMOTER OF CXCR4 GENE CONTRIBUTES TO INFLAMMATORY HYPERALGESIA. THESE FINDINGS PROVIDE A THEORETICAL BASIS FOR THE TREATMENT OF CHRONIC PAIN FROM AN EPIGENETIC PERSPECTIVE. 2018 9 1906 35 ENHANCER OF ZESTE HOMOLOG 2-CATALYSED H3K27 TRIMETHYLATION PLAYS A KEY ROLE IN ACUTE-ON-CHRONIC LIVER FAILURE VIA TNF-MEDIATED PATHWAY. ACUTE-ON-CHRONIC LIVER FAILURE IS MAINLY DUE TO HOST IMMUNITY SELF-DESTRUCTION. THE HISTONE H3 LYSINE 27 (H3K27) TRIMETHYLATING ENZYME, ENHANCER OF ZESTE HOMOLOG 2 (EZH2) MEDIATES EPIGENETIC SILENCING OF GENE EXPRESSION AND REGULATES IMMUNITY, ALSO INVOLVES PATHOGENESIS OF SEVERAL LIVER DISEASES. THE CURRENT STUDY WAS TO DETERMINE THE ROLE OF METHYLTRANSFERASE EZH2 AND ITS CATALYSED H3K27 TRIMETHYLATION (H3K27ME3) IN LIVER FAILURE, AND TO FURTHER INVESTIGATE THE POTENTIAL TARGET FOR LIVER FAILURE TREATMENT. EZH2 AND ITS CATALYSED H3K27ME3 WERE DETERMINED IN PERIPHERAL BLOOD MONONUCLEAR CELLS (PBMC) FROM LIVER FAILURE PATIENTS AND KUPFFER CELLS FROM EXPERIMENTAL MICE. FURTHERMORE, GSK126 (AN INHIBITOR FOR EZH2 TRIMETHYLATION FUNCTION) WAS APPLIED IN LIVER FAILURE MICE IN VIVO, AND LIPOPOLYSACCHARIDE-STIMULATED MONONUCLEAR CELLS IN VITRO. EZH2 AND H3K27ME3 WERE SIGNIFICANTLY UPREGULATED IN HUMAN PBMC FROM LIVER FAILURE PATIENTS OR MURINE KUPFFER CELLS FROM THE LIVER FAILURE ANIMALS, RESPECTIVELY. GSK126 AMELIORATED DISEASE SEVERITY IN LIVER FAILURE MICE, WHICH MAYBE ATTRIBUTE TO DOWN-REGULATE CIRCULATING AND HEPATIC PROINFLAMMATORY CYTOKINES, ESPECIALLY TNF VIA REDUCING H3K27ME3. IN-DEPTH CHROMATIN IMMUNOPRECIPITATION ANALYSIS UNRAVELLED THAT DECREASED ENRICHMENT OF H3K27ME3 ON TNF PROMOTOR, RESULTING IN TNF ELEVATION IN KUPFFER CELLS FROM LIVER FAILURE MICE. NUCLEAR FACTOR KAPPA B (NF-KAPPAB) AND PROTEIN KINASE B (AKT) SIGNALLING PATHWAYS WERE ACTIVATED UPON LIPOPOLYSACCHARIDE STIMULATION, BUT ATTENUATED BY USING GSK126, ACCOMPANIED WITH DECREASED TNF IN VITRO. IN CONCLUSION, EZH2 AND H3K27ME3 CONTRIBUTED TO THE PATHOGENESIS OF LIVER FAILURE VIA TRIGGERING TNF AND OTHER INDISPENSABLE PROINFLAMMATORY CYTOKINES. EZH2 WAS TO MODIFY H3K27ME3 ENRICHMENT, AS WELL AS, ACTIVATION OF THE DOWNSTREAM NF-KAPPAB AND AKT SIGNALLING PATHWAYS. 2018 10 5458 59 RESEARCH ON EPIGENETIC MECHANISM OF SFRP2 IN ADVANCED CHRONIC MYELOID LEUKEMIA. SECRETED FRIZZLED-RELATED PROTEIN 2 (SFRP2) HAS BEEN REPORTED TO ACT AS A TUMOR SUPPRESSORS. THIS STUDY AIMS TO DETECT THE BIOLOGICAL ROLE OF SFRP2 IN ADVANCED CHRONIC MYELOID LEUKEMIA (CML). IN THIS STUDY WE EXAMINED BONE MARROW SAMPLES FROM 45 CML PATIENTS AND 10 HEALTHY DONORS. K562 AND KCL22 CELLS WERE CULTURED AND TREATED WITH DEMETHYLATION DRUG AND HISTONE DEACETYLASE INHIBITOR (HDACI). KCL22 AND K562 CELLS WERE TRANSFECTED WITH LENTIVIRAL VECTOR (LV)-SFRP2, LV-CONTROL. THE CELLS WERE THEN SUBJECTED TO PROLIFERATION AND APOPTOSIS ASSAYS, REAL TIME POLYMERASE CHAIN REACTION (PCR), METHYLATION-SPECIFIC PCR (MSP), WESTERN BLOTTING, CO-IMMUNOPRECIPITATION (COIP) AND CHROMATIN IMMUNOPRECIPITATION (CHIP), WE FOUND THAT SFRP2 WAS DOWN-REGULATED IN THE ACCELERATED AND BLAST PHASE OF CML, WHEREAS, THE LEVELS OF WNT1, WNT3 AND WNT5A WERE UP-REGULATED IN THE ACCELERATED AND BLAST PHASE OF CML. OVEREXPRESSION SFRP2 INHIBITED PROLIFERATION, PROMOTED APOPTOSIS AND ACTIVATED THE WNT PATHWAY. COIP-MS RESULTS SHOWED THAT SFRP2 INTERACTED WITH WNT1 AND WNT5A. CHIP-SEQ RESULT INDICATED THAT THE PROMOTER OF H3K4ME3 AND H3K27ME3 WERE ABLE TO INTERACT WITH SFRP2. IN CONCLUSION, OUR FINDINGS DEMONSTRATED THE SFRP2 ACT AS A POTENTIAL THERAPEUTIC TARGET FOR ADVANCED CML. FURTHERMORE, OUR RESULTS SUPPORT THE USE OF DEMETHYLATION DRUGS AND HDACI AS A POTENTIAL CML TREATMENT STRATEGY. 2018 11 3832 26 INVOLVEMENT OF SPINAL SIRT1 IN DEVELOPMENT OF CHRONIC CONSTRICTION INJURY INDUCED NEUROPATHIC PAIN IN RATS. IT IS KNOWN THAT THE EPIGENETIC PROCESS OF HISTONE ACETYLATION IS INVOLVED IN THE NEUROPATHIC PAIN. THE AIM OF THIS STUDY WAS TO DETERMINE WHETHER SIRTUIN TYPE 1 (SIRT1), AN NAD(+) DEPENDENT DEACETYLASE, AFFECTED ALLODYNIA AND HYPERALGESIA IN NEUROPATHIC PAIN. THE NEUROPATHIC PAIN MODEL WAS ESTABLISHED BY LIGATURE OF THE RIGHT SCIATIC NERVE TO INDUCE CHRONIC CONSTRICTION INJURY (CCI) IN RATS. HISTONE ACETYLTRANSFERASE (HAT) ACTIVITY WAS INCREASED AND, AND HISTONE DEACETYLASE (HDAC) ACTIVITY WAS DECLINED IN TISSUE OF THE SPINAL DORSA HORN IN CCI RATES BY MEANS OF ENZYME-LINKED IMMUNOSORBENT ASSAY (ELISA). THE PERSISTENT HYPERALGESIA AND ALLODYNIA CAUSED BY CCI WERE ASSOCIATED WITH DOWNREGULATION OF SIRT1 AND UPREGULATION OF ACETYLATED-H3 (AC-H3) IN TISSUE OF THE SPINAL CORD BY WESTERN BLOT ASSAY, WHICH WAS REVERSED AFTER INTRATHECAL INJECTION OF SIRT1 AGONIST SRT1720. SRT1720 TREATMENT ACHIEVED ANALGESIC THROUGH INHIBITING THE ACETYLATION OF NUCLEAR FACTOR KAPPA B (NF-KAPPAB) AND BLOCKING THE RELEASES OF THE INFLAMMATORY FACTORS INCLUDING TUMOR NECROSIS FACTOR-ALPHA (TNF-ALPHA) AND INTERLEUKIN (IL)-6 BY MEANS OF WESTERN BLOT AND REAL-TIME QUANTITATIVE PCR (RT-PCR), RESPECTIVELY. TAKEN TOGETHER, THESE DATA SUGGEST THAT SIRT1 IN THE SPINAL CORD PLAYS AN IMPORTANT ROLE IN THE NEUROPATHIC PAIN IN THE RAT MODEL. 2018 12 5976 22 TET1-DEPENDENT EPIGENETIC MODIFICATION OF BDNF EXPRESSION IN DORSAL HORN NEURONS MEDIATES NEUROPATHIC PAIN IN RATS. TEN-ELEVEN TRANSLOCATION METHYLCYTOSINE DIOXYGENASE 1 (TET1) MEDIATES THE CONVERSION OF 5-METHYLCYTOSINE (5 MC) TO 5-HYDROXYMETHYLCYTOSINE (5 HMC), HENCE PROMOTING DNA DEMETHYLATION. ALTHOUGH RECENT STUDIES HAVE LINKED THE DNA DEMETHYLATION OF SPECIFIC GENES TO PAIN HYPERSENSITIVITY, THE ROLE OF SPINAL TET1-DEPENDENT DNA DEMETHYLATION IN NOCICEPTION HYPERSENSITIVITY DEVELOPMENT REMAINS ELUSIVE. HERE, WE REPORT CORRELATED WITH BEHAVIORAL ALLODYNIA, SPINAL NERVE LIGATION (SNL) UPREGULATED TET1 EXPRESSION IN DORSAL HORN NEURONS THAT HYDROXYLATE 5 MC TO 5 HMC AT CPG DINUCLEOTIDES IN THE BDNF PROMOTER TO PROMOTE SPINAL BDNF EXPRESSION AT DAY 7 AFTER OPERATION. FOCAL KNOCKDOWN OF SPINAL TET1 EXPRESSION DECREASED TET1 BINDING AND 5 HMC ENRICHMENT, FURTHER INCREASED 5 MC ENRICHMENT AT CPG SITES IN THE BDNF PROMOTER AND DECREASED SPINAL BDNF EXPRESSION ACCOMPANIED BY THE ALLEVIATION OF THE DEVELOPED ALLODYNIA. MOREOVER, AT DAY 7 AFTER OPERATION, SNL-ENHANCED TET1 EXPRESSION ALSO INHIBITED THE BINDING OF DNA METHYLTRANSFERASES (DNMTS, I.E., DNMT1, DNMT3A, AND DNMT3B) TO THE BDNF PROMOTER, A REQUIREMENT FOR TRANSCRIPTIONAL SILENCING BY CATALYSING 5-CYTOSINE (5C) TO 5 MC. TOGETHER, THESE DATA SUGGEST AT CPG SITES OF THE BDNF PROMOTER, SNL-ENHANCED TET1 EXPRESSION PROMOTES DNA DEMETHYLATION BOTH BY CONVERTING 5 MC TO 5 HMC AND INHIBITING DNMT BINDING TO REGULATE SPINAL BDNF EXPRESSION, HENCE CONTRIBUTING TO BEHAVIORAL ALLODYNIA DEVELOPMENT. 2016 13 4076 32 MATERNAL HIGH-FAT DIET MODIFIES EPIGENETIC MARKS H3K27ME3 AND H3K27AC IN BONE TO REGULATE OFFSPRING OSTEOBLASTOGENESIS IN MICE. STUDIES FROM BOTH HUMANS AND ANIMAL MODELS INDICATED THAT MATERNAL CHRONIC POOR-QUALITY DIET, ESPECIALLY A HIGH FAT DIET (HFD), IS SIGNIFICANTLY ASSOCIATED WITH REDUCED BONE DENSITY AND CHILDHOOD FRACTURES IN OFFSPRING. WHEN PREVIOUSLY STUDIED IN A RAT MODEL, OUR DATA SUGGESTED THAT MATERNAL HFD CHANGES EPIGENETIC MARKS SUCH AS DNA METHYLATION AND HISTONE MODIFICATIONS TO CONTROL OSTEOBLAST METABOLISM. IN MOUSE EMBRYONIC AND POSTNATAL OFFSPRING BONE SAMPLES, A CHIP-SEQUENCING (CHIP-SEQ)-BASED GENOME-WIDE METHOD WAS USED TO LOCATE THE REPRESSIVE HISTONE MARK H3K27ME3 (MEDIATED VIA THE POLYCOMB HISTONE METHYLTRANSFERASE, EZH2) AND EXPRESSIVE HISTONE MARK H3K27AC (P300/CBP MEDIATED) THROUGHOUT THE GENOME. USING ISOLATED MOUSE EMBRYONIC CELLS FROM FOETAL CALVARIA (OSTEOBLAST-LIKE CELLS), H3K27ME3 CHIP-SEQ SHOWED THAT 147 GENE BODIES AND 26 GENE PROMOTERS IN HFD EMBRYOTIC SAMPLES HAD A GREATER THAN TWOFOLD INCREASE IN H3K27ME PEAKS COMPARED TO CONTROLS. AMONG THE HFD SAMPLES, PTHLH AND COL2A1 THAT ARE IMPORTANT GENES PLAYING ROLES DURING CHONDRO- AND OSTEOGENESIS HAD SIGNIFICANTLY ENRICHED LEVELS OF H3K27ME3. THEIR DECREASED MRNA EXPRESSION WAS CONFIRMED BY REAL-TIME PCR AND STANDARD CHIP ANALYSIS, INDICATING A STRONG ASSOCIATION WITH EZH2 MEDIATED H3K27ME3 EPIGENETIC CHANGES. USING EMBRYONIC CALVARIA OSTEOBLASTIC CELLS AND OFFSPRING BONE SAMPLES, H3K27AC CHIP-SEQ ANALYSIS SHOWED THAT OSTEOBLAST INHIBITOR GENES TNFAIP3 AND TWIST1 HAD SIGNIFICANTLY ENRICHED PEAKS OF H3K27AC IN HFD SAMPLES COMPARED TO CONTROLS. THEIR INCREASED GENE EXPRESSION AND ASSOCIATION WITH H3K27AC WERE ALSO CONFIRMED BY REAL-TIME PCR AND STANDARD CHIP ANALYSIS. THESE FINDINGS INDICATE THAT CHRONIC MATERNAL HFD CHANGES HISTONE TRIMETHYLATION AND ACETYLATION EPIGENETIC MARKS TO REGULATE EXPRESSION OF GENES CONTROLLING OSTEOBLASTOGENESIS. 2022 14 1831 34 EFFECTS OF MATERNAL SEPARATION AND ANTIDEPRESSANT DRUG ON EPIGENETIC REGULATION OF THE BRAIN-DERIVED NEUROTROPHIC FACTOR EXON I PROMOTER IN THE ADULT RAT HIPPOCAMPUS. AIM: EARLY LIFE STRESS CAN INDUCE EPIGENETIC CHANGES THROUGH GENETIC AND ENVIRONMENTAL INTERACTIONS AND IS A RISK FACTOR FOR DEPRESSION. BRAIN-DERIVED NEUROTROPHIC FACTOR (BDNF) HAS BEEN IMPLICATED IN THE PATHOPHYSIOLOGY OF DEPRESSION AND ANTIDEPRESSANT DRUG ACTION. WE INVESTIGATED EPIGENETIC CHANGES AT THE BDNF EXON I PROMOTER IN THE HIPPOCAMPUS OF ADULT RATS SUBJECTED TO MATERNAL SEPARATION (MS) DURING EARLY LIFE AND TREATED WITH AN ANTIDEPRESSANT DRUG AS ADULTS. METHODS: RAT PUPS WERE SUBJECTED TO MS FROM POSTNATAL DAY 1 TO 21 AND RECEIVED CHRONIC ESCITALOPRAM (ESC) AS ADULTS. WE ASSESSED THE EFFECTS OF MS AND ESC ON BDNF EXON I AND DNA METHYLTRANSFERASES (DNMT) MRNA LEVELS (QUANTITATIVE REVERSE-TRANSCRIPTION POLYMERASE CHAIN REACTION), ACETYLATED HISTONE H3, AND MECP2 BINDING TO THE BDNF PROMOTER I (CHROMATIN IMMUNOPRECIPITATION FOLLOWED BY REAL-TIME POLYMERASE CHAIN REACTION), AND BDNF PROTEIN LEVELS (ENZYME-LINKED IMMUNOSORBENT ASSAY). RESULTS: THE LEVELS OF BDNF PROTEIN, EXON I MRNA, HISTONE H3 ACETYLATION, AND DNMT1 AND DNMT3A MRNA WERE ALTERED IN THE MS GROUP COMPARED WITH THE CONTROL GROUP. SIGNIFICANT DECREASES WERE OBSERVED IN THE BDNF PROTEIN, EXON I MRNA, AND HISTONE H3 ACETYLATION LEVELS AND THERE WERE SIGNIFICANT INCREASES IN DNMT1 AND DNMT3A MRNA LEVELS. THE COMPARISON BETWEEN THE MS + ESC AND MS GROUPS REVEALED SIGNIFICANT INCREASES IN BDNF PROTEIN, EXON I MRNA, AND HISTONE H3 ACETYLATION LEVELS AND SIGNIFICANT DECREASES IN MECP2 AND DNMT1 AND DNMT3A MRNA LEVELS. CONCLUSION: THESE FINDINGS INDICATE THAT MS INDUCED EPIGENETIC CHANGES AT THE BDNF EXON I PROMOTER AND THESE CHANGES WERE PREVENTED BY ANTIDEPRESSANT DRUG TREATMENT DURING ADULTHOOD. 2018 15 574 40 BCR/ABL INCREASES EZH2 LEVELS WHICH REGULATES XIAP EXPRESSION VIA MIRNA-219 IN CHRONIC MYELOID LEUKEMIA CELLS. IN THIS STUDY, WE SHOWED THAT THE LEVELS OF EZH2 IN BONE MARROW MONONUCLEAR CELLS (BMMNCS) ISOLATED FROM INDIVIDUALS WITH CHRONIC MYELOID LEUKEMIA (CML) (N=12) WERE SIGNIFICANTLY GREATER THAN THOSE IN BMMNCS ISOLATED FROM HEALTHY VOLUNTEERS (N=6) AS WELL AS INDIVIDUALS WITH PHILADELPHIA CHROMOSOME-NEGATIVE MYELOPROLIFERATIVE NEOPLASMS. LENTIVIRAL TRANSDUCTION OF THE BCR/ABL GENE IN BA/F3 CELLS INCREASED EZH2 LEVELS IN PARALLEL WITH PHOSPHORYLATION OF STAT5. NOTABLY, CHROMATIN IMMUNOPRECIPITATION ASSAYS SHOWED THAT STAT5A BOUND TO A PROMOTER REGION OF THE EZH2 GENE, RESULTING IN AN INCREASE IN THE TRANSCRIPTIONAL ACTIVITY OF EZH2 IN LEUKEMIA CELLS. IMPORTANTLY, DOWNREGULATION OF EZH2 BY SHORT HAIRPIN RNAS (SHRNAS) INHIBITED THE EXPRESSION OF XIAP AND INCREASED THE MIR-219 LEVELS ASSOCIATED WITH A DECREASE IN HYPERMETHYLATION OF MIR-219-1 CPG ISLANDS. MOREOVER, OVEREXPRESSION OF MIR-219 DECREASED THE LEVELS OF XIAP IN CML CELLS. SINCE THE 3'-UNTRANSLATED REGION (3'-UTR) OF XIAP CONTAINS MIR219-5P-COMPLEMENTARY BINDING SITE, MIR-219 MIGHT MODULATE THE EXPRESSION OF XIAP THROUGH BINDING OF MIR-219 ON THE 3'-UTR OF XIAP. TAKEN TOGETHER, BCR/ABL POSITIVELY REGULATES THE EXPRESSION OF EZH2 VIA STAT5 SIGNALING. EZH2 MODULATES EPIGENETIC CHANGES AT DNA METHYLATED REGIONS ENCODING MIR-219 AND DOWNREGULATES THE LEVEL OF MIR-219, RESULTING IN UPREGULATION OF XIAP. 2016 16 2197 23 EPIGENETIC MODIFICATION OF BDNF MEDIATES NEUROPATHIC PAIN VIA MIR-30A-3P/EP300 AXIS IN CCI RATS. RECENT INVESTIGATION OF MICRORNAS ON CHRONIC PAIN HAS DEVELOPED A BREAKTHROUGH IN NEUROPATHIC PAIN MANAGEMENT. IN THE PRESENT STUDY, DECREASED EXPRESSION OF MIR-30A-3P WAS REPORTED USING QRT-PCR ANALYSIS AND LOSS OF MIR-30A-3P PROMOTED NEUROPATHIC PAIN PROGRESSION IN SCIATIC NERVE CHRONIC CONSTRICTIVE INJURY RATS THROUGH DETERMINING THE PAIN THRESHOLD. WE PREDICTED MIR-30A-3P COULD TARGET E-CADHERIN TRANSCRIPTIONAL ACTIVATOR (EP300) VIA BIOINFORMATICS ANALYSIS. MEANWHILE, WE FOUND THAT BRAIN-DERIVED NEUROTROPHIC FACTOR (BDNF) IS INVOLVED IN NEUROPATHIC PAIN. HERE, WE EXHIBITED THAT EP300 EPIGENETICALLY UP-REGULATED BDNF VIA ENHANCING ACETYLATED HISTONE H3 AND H4 ON THE PROMOTER. FOR ANOTHER, MIR-30A-3P WAS ABLE TO MODIFY THE LEVEL OF BDNF AND ACETYLATED HISTONE H3 AND H4. LOSS OF MIR-30A-3P ENHANCED EP300 AND BDNF COLOCALIZATION IN CCI RATS. SUBSEQUENTLY, IT WAS SHOWN THAT INCREASED EP300 INDUCED NEUROPATHIC PAIN BY AN ENHANCEMENT OF NEURONAL BDNF LEVEL IN VIVO. TO SUM UP, IT WAS REVEALED THAT EPIGENETIC MODIFICATION OF BDNF PROMOTED NEUROPATHIC PAIN VIA EP300 INDUCED BY MIR-30A-3P IN CCI RATS. 2020 17 2825 36 FLOW-DEPENDENT EPIGENETIC REGULATION OF IGFBP5 EXPRESSION BY H3K27ME3 CONTRIBUTES TO ENDOTHELIAL ANTI-INFLAMMATORY EFFECTS. RATIONALE: ATHEROSCLEROSIS IS A CHRONIC INFLAMMATORY AND EPIGENETIC DISEASE THAT IS INFLUENCED BY DIFFERENT PATTERNS OF BLOOD FLOW. HOWEVER, THE EPIGENETIC MECHANISM WHEREBY ATHEROPROTECTIVE FLOW CONTROLS ENDOTHELIAL GENE PROGRAMMING REMAINS ELUSIVE. HERE, WE INVESTIGATED THE POSSIBILITY THAT FLOW ALTERS ENDOTHELIAL GENE EXPRESSION THROUGH EPIGENETIC MECHANISMS. METHODS: EN FACE STAINING AND WESTERN BLOT WERE USED TO DETECT PROTEIN EXPRESSION. REAL-TIME PCR WAS USED TO DETERMINE RELATIVE GENE EXPRESSION. RNA-SEQUENCING OF HUMAN UMBILICAL VEIN ENDOTHELIAL CELLS TREATED WITH SIRNA OF ENHANCER OF ZESTE HOMOLOG 2 (EZH2) OR LAMINAR FLOW WAS USED FOR TRANSCRIPTIONAL PROFILING. RESULTS: WE FOUND THAT TRIMETHYLATION OF HISTONE 3 LYSINE 27 (H3K27ME3), A REPRESSIVE EPIGENETIC MARK THAT ORCHESTRATES GENE REPRESSION, WAS REDUCED IN LAMINAR FLOW AREAS OF MOUSE AORTA AND FLOW-TREATED HUMAN ENDOTHELIAL CELLS. THE DECREASE OF H3K27ME3 PARALLELED A REDUCTION IN THE EPIGENETIC "WRITER"-EZH2, THE CATALYTIC SUBUNIT OF THE POLYCOMB REPRESSIVE COMPLEX 2 (PRC2). MOREOVER, LAMINAR FLOW DECREASED EXPRESSION OF EZH2 VIA MECHANOSENSITIVE MIR101. GENOME-WIDE TRANSCRIPTOME PROFILING STUDIES IN ENDOTHELIAL CELLS TREATED WITH EZH2 SIRNA AND FLOW REVEALED THE UPREGULATION OF NOVEL MECHANOSENSITIVE GENE IGFBP5 (INSULIN-LIKE GROWTH FACTOR-BINDING PROTEIN 5), WHICH IS EPIGENETICALLY SILENCED BY H3K27ME3. FUNCTIONALLY, INHIBITION OF H3K27ME3 BY EZH2 SIRNA OR GSK126 (A SPECIFIC EZH2 INHIBITOR) REDUCED H3K27ME3 LEVELS AND MONOCYTE ADHESION TO ENDOTHELIAL CELLS. ADENOVIRAL OVEREXPRESSION OF IGFBP5 ALSO RECAPITULATED THE ANTI-INFLAMMATORY EFFECTS OF H3K27ME3 INHIBITION. MORE IMPORTANTLY, WE OBSERVED EZH2 UPREGULATION, AND IGFBP5 DOWNREGULATION, IN ADVANCED ATHEROSCLEROTIC PLAQUES FROM HUMAN PATIENTS. CONCLUSION: TAKEN TOGETHER, OUR FINDINGS REVEAL THAT ATHEROPROTECTIVE FLOW REDUCES H3K27ME3 AS A CHROMATIN-BASED MECHANISM TO AUGMENT THE EXPRESSION OF GENES THAT CONFER AN ANTI-INFLAMMATORY RESPONSE IN THE ENDOTHELIUM. OUR STUDY EXEMPLIFIES FLOW-DEPENDENT EPIGENETIC REGULATION OF ENDOTHELIAL GENE EXPRESSION, AND ALSO SUGGESTS THAT TARGETING THE EZH2/H3K27ME3/IGFBP5 PATHWAY MAY OFFER NOVEL THERAPEUTICS FOR INFLAMMATORY DISORDERS SUCH AS ATHEROSCLEROSIS. 2018 18 6612 23 ULTRA-LOW-DOSE NALOXONE ENHANCES THE ANTINOCICEPTIVE EFFECT OF MORPHINE IN PTX-TREATED RATS: REGULATION ON GLOBAL HISTONE METHYLATION. OBJECTIVE: EPIGENETIC REPROGRAMMING MAY HAVE A POSSIBLE ROLE IN NEUROPATHIC PAIN DEVELOPMENT; THE PRESENT STUDY EXAMINED THE GLOBAL PATTERNS OF LYSINE HISTONE MODIFICATION. IN THIS SERIAL STUDY WE ANALYZED THE LEVELS OF HISTONE 3 LYSINE 4 MONOMETHYLATION, HISTONE 3 LYSINE 4 DIMETHYLATION, AND HISTONE 3 LYSINE 9 TRIMETHYLATION IN PERTUSSIS TOXIN (PTX)-INDUCED THERMAL HYPERALGESIC RAT SPINAL CORDS. METHODS: MALE WISTAR RATS IMPLANTED WITH AN INTRATHECAL CATHETER RECEIVED A SINGLE INTRATHECAL PTX (1 MUG IN 5 MUL SALINE) INJECTION. FOUR DAYS LATER, THEY WERE RANDOMLY ASSIGNED TO RECEIVE EITHER A SINGLE INJECTION OF SALINE, OR ULTRA-LOW-DOSE NALOXONE (15 NG IN 5 MUL SALINE), FOLLOWED BY MORPHINE (10 MUG IN 5 MUL SALINE) INJECTION 30 MINUTES LATER. RESULTS: THE RESULTS SHOWED THAT PTX INJECTION INDUCED THERMAL HYPERALGESIA AND SIGNIFICANT INCREASE OF GLOBAL HISTONE METHYLATION IN THE SPINAL CORDS. INTRATHECAL MORPHINE ALONE DID NOT AFFECT THE THERMAL HYPERALGESIA AND GLOBAL HISTONE METHYLATION. IN CONTRAST, INTRATHECAL ADMINISTRATION OF ULTRA-LOW-DOSE NALOXONE PLUS MORPHINE SIGNIFICANTLY ATTENUATED THE PTX-INDUCED THERMAL HYPERALGESIA AND DOWN-REGULATED THE GLOBAL HISTONE METHYLATION. CONCLUSION: THE RESULTS SUGGEST THAT ULTRA-LOW-DOSE NALOXONE MIGHT BE CLINICAL VALUABLE FOR NEUROPATHIC PAIN MANAGEMENT VIA REGULATING GLOBAL HISTONE MODIFICATION. 2012 19 917 33 CHRONIC HIGH-FAT DIET DRIVES POSTNATAL EPIGENETIC REGULATION OF MU-OPIOID RECEPTOR IN THE BRAIN. OPIOID SYSTEM DYSREGULATION HAS BEEN OBSERVED IN BOTH GENETIC AND HIGH-FAT DIET (HFD)-INDUCED MODELS OF OBESITY. AN UNDERSTANDING OF THE MOLECULAR MECHANISMS OF MOR TRANSCRIPTIONAL REGULATION, PARTICULARLY WITHIN AN IN VIVO CONTEXT, IS LACKING. USING A DIET-INDUCED MODEL OF OBESITY (DIO), MICE WERE FED A HIGH-FAT DIET (60% CALORIES FROM FAT) FROM WEANING TO >18 WEEKS OF AGE. COMPARED WITH MICE FED THE CONTROL DIET, DIO MICE HAD A DECREASED PREFERENCE FOR SUCROSE. MOR MRNA EXPRESSION WAS DECREASED IN REWARD-RELATED CIRCUITRY (VENTRAL TEGMENTAL AREA (VTA), NUCLEUS ACCUMBENS (NAC), AND PREFRONTAL CORTEX (PFC)) BUT NOT THE HYPOTHALAMUS, IMPORTANT IN THE HOMEOSTATIC REGULATION OF FEEDING. DNA METHYLATION IS AN EPIGENETIC MODIFICATION THAT LINKS ENVIRONMENTAL EXPOSURES TO ALTERED GENE EXPRESSION. WE FOUND A SIGNIFICANT INCREASE IN DNA METHYLATION IN THE MOR PROMOTER REGION WITHIN THE REWARD-RELATED BRAIN REGIONS. METHYL CPG-BINDING PROTEIN 2 (MECP2) CAN BIND METHYLATED DNA AND REPRESS TRANSCRIPTION, AND DIO MICE SHOWED INCREASED BINDING OF MECP2 TO THE MOR PROMOTER IN REWARD-RELATED REGIONS OF THE BRAIN. FINALLY, USING CHIP ASSAYS WE EXAMINED H3K9 METHYLATION (INACTIVE CHROMATIN) AND H3 ACETYLATION (ACTIVE CHROMATIN) WITHIN THE MOR PROMOTER REGION AND FOUND INCREASED H3K9 METHYLATION AND DECREASED H3 ACETYLATION. THESE DATA ARE THE FIRST TO IDENTIFY DNA METHYLATION, MECP2 RECRUITMENT, AND CHROMATIN REMODELING AS MECHANISMS LEADING TO TRANSCRIPTIONAL REPRESSION OF MOR IN THE BRAINS OF MICE FED A HIGH-FAT DIET. 2011 20 1631 38 DNMT3A METHYLATION IN NEUROPATHIC PAIN. BACKGROUND: MU OPIOID RECEPTOR (MOR) PLAYS A CRUCIAL ROLE IN MEDIATING ANALGESIC EFFECTS OF OPIOIDS AND IS CLOSELY ASSOCIATED WITH THE PATHOLOGIES OF NEUROPATHIC PAIN. PREVIOUS STUDIES HAVE REPORTED THAT PERIPHERAL NERVE INJURY DOWNREGULATES MOR EXPRESSION, BUT THE EPIGENETIC MECHANISMS REMAIN UNKNOWN. OBJECTIVE: THEREFORE, WE INVESTIGATED DNA METHYLTRANSFERASE3A (DNMT3A) EXPRESSION OR METHYLATION CHANGES WITHIN MOR PROMOTER IN THE SPINAL CORD IN A NEUROPATHIC PAIN INDUCED BY A CHRONIC CONSTRICTION INJURY (CCI) MOUSE MODEL AND FURTHER DETERMINED WHETHER THESE INJURY-ASSOCIATED CHANGES ARE REVERSIBLE BY PHARMACOLOGICAL INTERVENTIONS. METHODS: A CCI MOUSE MODEL WAS ESTABLISHED AND TISSUE SPECIMENS OF LUMBAR SPINAL CORDS WERE COLLECTED. THE NOCICEPTION THRESHOLD WAS EVALUATED BY A MODEL HEATED 400 BASE. DNMT3A AND MOR MRNA AND PROTEIN LEVEL WERE DETECTED BY REAL-TIME-POLYMERASE CHAIN REACTION AND WESTERN BLOT, RESPECTIVELY. METHYLATION OF DNMT3A GENE WAS MEASURED BY METHYLATION-SPECIFIC PCR. RESULTS: OUR DATA SHOWED THAT CHRONIC NERVE INJURY LED TO A SIGNIFICANT UPREGULATION OF DNMT3A EXPRESSION THAT WAS ASSOCIATED WITH INCREASED METHYLATION OF MOR GENE PROMOTER AND DECREASED MOR PROTEIN EXPRESSION IN THE SPINAL CORD. INHIBITION OF DNMT3A CATALYTIC ACTIVITY WITH DNMT INHIBITOR RG108 SIGNIFICANTLY BLOCKED THE INCREASE IN METHYLATION OF THE MOR PROMOTER, AND THEN UPREGULATED MOR EXPRESSION AND ATTENUATED THERMAL HYPERALGESIA IN NEUROPATHIC PAIN MICE. CONCLUSION: THIS STUDY DEMONSTRATES THAT AN INCREASE OF DNMT3A EXPRESSION AND MOR METHYLATION EPIGENETICALLY PLAY AN IMPORTANT ROLE IN NEUROPATHIC PAIN. TARGETING DNMT3A TO THE PROMOTER OF MOR GENE BY DNMT INHIBITOR MAY BE A PROMISING APPROACH TO THE DEVELOPMENT OF NEW NEUROPATHIC PAIN THERAPY. 2017