1 2300 118 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 2 1826 37 EFFECTS OF HISTONE DEACETYLASE INHIBITOR ON EXTRACELLULAR MATRIX PRODUCTION IN HUMAN NASAL POLYP ORGAN CULTURES. BACKGROUND: NASAL POLYPOSIS IS ASSOCIATED WITH A CHRONIC INFLAMMATORY CONDITION OF THE SINONASAL MUCOSA AND INVOLVES MYOFIBROBLAST DIFFERENTIATION AND EXTRACELLULAR MATRIX (ECM) ACCUMULATION. EPIGENETIC MODULATION BY HISTONE DEACETYLASE (HDAC) INHIBITORS INCLUDING TRICHOSTATIN A (TSA) HAS BEEN REPORTED TO HAVE INHIBITORY EFFECTS ON MYOFIBROBLAST DIFFERENTIATION IN LUNG AND RENAL FIBROBLASTS. THE PURPOSE OF THIS STUDY WAS TO INVESTIGATE THE INHIBITORY EFFECT OF TSA ON MYOFIBROBLAST DIFFERENTIATION AND ECM PRODUCTION IN NASAL POLYP ORGAN CULTURES. METHODS: NASAL POLYP TISSUES FROM 18 PATIENTS WERE ACQUIRED DURING ENDOSCOPIC SINUS SURGERY. AFTER ORGAN CULTURE, NASAL POLYPS WERE STIMULATED WITH TGF-BETA1 AND THEN TREATED WITH TSA. ALPHA-SMOOTH MUSCLE ACTIN (ALPHA-SMA), FIBRONECTIN, AND COLLAGEN TYPE I EXPRESSION LEVELS WERE EXAMINED BY REVERSE TRANSCRIPTION-POLYMERASE CHAIN REACTION (PCR), REAL-TIME PCR, WESTERN BLOT, AND IMMUNOFLUORESCENT STAINING. HDAC2, HDAC4, AND ACETYLATED H4 EXPRESSION LEVELS WERE ASSAYED BY WESTERN BLOT. CYTOTOXICITY WAS ANALYZED BY THE TERMINAL DEOXYNUCLEOTIDYL TRANSFERASE BIOTIN-DUTP NICK END LABELING ASSAY. RESULTS: THE EXPRESSION LEVELS OF ALPHA-SMA, FIBRONECTIN, AND COLLAGEN TYPE 1 WERE INCREASED IN NASAL POLYP AFTER TRANSFORMING GROWTH FACTOR (TGF) BETA1 TREATMENT. TSA-INHIBITED TGF-BETA1 INDUCED THESE GENE AND PROTEIN EXPRESSION LEVELS. FURTHERMORE, TSA SUPPRESSED PROTEIN EXPRESSION LEVELS OF HDAC2 AND HDAC4. HOWEVER, TSA INDUCED HYPERACETYLATION OF HISTONES H4. TREATMENT WITH TGF-BETA1 WITH OR WITHOUT TSA DID NOT HAVE CYTOTOXIC EFFECT. CONCLUSION: THESE FINDINGS PROVIDE NOVEL INSIGHTS INTO THE EPIGENETIC REGULATION IN MYOFIBROBLAST DIFFERENTIATION AND ECM PRODUCTION OF NASAL POLYP. TSA COULD BE A CANDIDATE OF A THERAPEUTIC AGENT FOR REVERSING THE TGF-BETA1-INDUCED ECM SYNTHESIS THAT LEADS TO NASAL POLYP DEVELOPMENT. 2013 3 1945 27 EPIGALLOCATECHIN-3-GALLATE, A HISTONE ACETYLTRANSFERASE INHIBITOR, INHIBITS EBV-INDUCED B LYMPHOCYTE TRANSFORMATION VIA SUPPRESSION OF RELA ACETYLATION. BECAUSE THE P300/CBP-MEDIATED HYPERACETYLATION OF RELA (P65) IS CRITICAL FOR NUCLEAR FACTOR-KAPPAB (NF-KAPPAB) ACTIVATION, THE ATTENUATION OF P65 ACETYLATION IS A POTENTIAL MOLECULAR TARGET FOR THE PREVENTION OF CHRONIC INFLAMMATION. DURING OUR ONGOING SCREENING STUDY TO IDENTIFY NATURAL COMPOUNDS WITH HISTONE ACETYLTRANSFERASE INHIBITOR (HATI) ACTIVITY, WE IDENTIFIED EPIGALLOCATECHIN-3-GALLATE (EGCG) AS A NOVEL HATI WITH GLOBAL SPECIFICITY FOR THE MAJORITY OF HAT ENZYMES BUT WITH NO ACTIVITY TOWARD EPIGENETIC ENZYMES INCLUDING HDAC, SIRT1, AND HMTASE. AT A DOSE OF 100 MICROMOL/L, EGCG ABROGATES P300-INDUCED P65 ACETYLATION IN VITRO AND IN VIVO, INCREASES THE LEVEL OF CYTOSOLIC IKAPPABALPHA, AND SUPPRESSES TUMOR NECROSIS FACTOR ALPHA (TNFALPHA)-INDUCED NF-KAPPAB ACTIVATION. WE ALSO SHOWED THAT EGCG PREVENTS TNFALPHA-INDUCED P65 TRANSLOCATION TO THE NUCLEUS, CONFIRMING THAT HYPERACETYLATION IS CRITICAL FOR NF-KAPPAB TRANSLOCATION AS WELL AS ACTIVITY. FURTHERMORE, EGCG TREATMENT INHIBITED THE ACETYLATION OF P65 AND THE EXPRESSION OF NF-KAPPAB TARGET GENES IN RESPONSE TO DIVERSE STIMULI. FINALLY, EGCG REDUCED THE BINDING OF P300 TO THE PROMOTER REGION OF INTERLEUKIN-6 GENE WITH AN INCREASED RECRUITMENT OF HDAC3, WHICH HIGHLIGHTS THE IMPORTANCE OF THE BALANCE BETWEEN HATS AND HISTONE DEACETYLASES IN THE NF-KAPPAB-MEDIATED INFLAMMATORY SIGNALING PATHWAY. IMPORTANTLY, EGCG AT 50 MICROMOL/L DOSE COMPLETELY BLOCKS EBV INFECTION-INDUCED CYTOKINE EXPRESSION AND SUBSEQUENTLY THE EBV-INDUCED B LYMPHOCYTE TRANSFORMATION. THESE RESULTS SHOW THE CRUCIAL ROLE OF ACETYLATION IN THE DEVELOPMENT OF INFLAMMATORY-RELATED DISEASES. 2009 4 3832 38 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 5 1906 31 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 6 2353 48 EPIGENETIC REGULATION OF OPIOID-INDUCED HYPERALGESIA, DEPENDENCE, AND TOLERANCE IN MICE. REPEATED ADMINISTRATION OF OPIOIDS SUCH AS MORPHINE INDUCES PERSISTENT BEHAVIORAL CHANGES INCLUDING OPIOID-INDUCED HYPERALGESIA (OIH), TOLERANCE, AND PHYSICAL DEPENDENCE. IN THE CURRENT WORK WE EXPLORED HOW THE BALANCE OF HISTONE ACETYLTRANSFERASE (HAT) VERSUS HISTONE DEACETYLASE (HDAC) MIGHT REGULATE THESE MORPHINE-INDUCED CHANGES. NOCICEPTIVE THRESHOLDS, ANALGESIA, AND PHYSICAL DEPENDENCE WERE ASSESSED DURING AND FOR A PERIOD OF SEVERAL WEEKS AFTER MORPHINE EXPOSURE. TO PROBE THE ROLES OF HISTONE ACETYLATION, THE HAT INHIBITOR CURCUMIN OR A SELECTIVE HDAC INHIBITOR SUBEROYLANILIDE HYDROXAMIC ACID (SAHA) WAS ADMINISTERED DAILY TO GROUPS OF ANIMALS. HISTONE ACETYLATION IN SPINAL CORD WAS ASSESSED BY WESTERN BLOT AND IMMUNOHISTOCHEMISTRY. CONCURRENT ADMINISTRATION OF CURCUMIN WITH MORPHINE FOR 4 DAYS SIGNIFICANTLY REDUCED DEVELOPMENT OF OPIOID-INDUCED MECHANICAL ALLODYNIA, THERMAL HYPERALGESIA, TOLERANCE, AND PHYSICAL DEPENDENCE. CONVERSELY, THE HDAC INHIBITOR SAHA ENHANCED THESE RESPONSES. INTERESTINGLY, SAHA TREATMENT AFTER THE TERMINATION OF OPIOID ADMINISTRATION SUSTAINED THESE BEHAVIORAL CHANGES FOR AT LEAST 4 WEEKS. HISTONE H3 ACETYLATION IN THE DORSAL HORN OF THE SPINAL CORD WAS INCREASED AFTER CHRONIC MORPHINE TREATMENT, BUT H4 ACETYLATION WAS UNCHANGED. MOREOVER, WE OBSERVED A DECREASE IN HDAC ACTIVITY IN THE SPINAL CORDS OF MORPHINE-TREATED MICE WHILE OVERALL HAT ACTIVITY WAS UNCHANGED, SUGGESTING A SHIFT TOWARD A STATE OF ENHANCED HISTONE ACETYLATION. PERSPECTIVE: THE CURRENT STUDY INDICATES THAT EPIGENETIC MECHANISMS PLAY A CRUCIAL ROLE IN OPIOID-INDUCED LONG-LASTING NEUROPLASTICITY. THESE RESULTS PROVIDE NEW SIGHT INTO UNDERSTANDING THE MECHANISMS OF OPIOID-INDUCED NEUROPLASTICITY AND SUGGEST NEW STRATEGIES TO LIMIT OPIOID ABUSE POTENTIAL AND INCREASE THE VALUE OF THESE DRUGS AS ANALGESICS. 2013 7 5860 35 SULFORAPHANE PREVENTS ANGIOTENSIN II-INDUCED CARDIOMYOPATHY BY ACTIVATION OF NRF2 THROUGH EPIGENETIC MODIFICATION. NUCLEAR FACTOR ERYTHROID 2-RELATED FACTOR (NRF2) IS AN IMPORTANT REGULATOR OF CELLULAR ANTIOXIDANT DEFENCE. WE PREVIOUSLY SHOWED THAT SFN PREVENTED ANG II-INDUCED CARDIAC DAMAGE VIA ACTIVATION OF NRF2. HOWEVER, THE UNDERLYING MECHANISM OF SFN'S PERSISTENT CARDIAC PROTECTION REMAINS UNCLEAR. THIS STUDY AIMED TO EXPLORE THE POTENTIAL OF SFN IN ACTIVATING CARDIAC NRF2 THROUGH EPIGENETIC MECHANISMS. WILD-TYPE MICE WERE INJECTED SUBCUTANEOUSLY WITH ANG II, WITH OR WITHOUT SFN. ADMINISTRATION OF CHRONIC ANG II-INDUCED CARDIAC INFLAMMATORY FACTOR EXPRESSION, OXIDATIVE DAMAGE, FIBROSIS AND CARDIAC REMODELLING AND DYSFUNCTION, ALL OF WHICH WERE EFFECTIVELY IMPROVED BY SFN TREATMENT, COUPLED WITH AN UP-REGULATION OF NRF2 AND DOWNSTREAM GENES. BISULFITE GENOME SEQUENCING AND CHROMATIN IMMUNOPRECIPITATION (CHIP) WERE PERFORMED TO DETECT THE METHYLATION LEVEL OF THE FIRST 15 CPGS AND HISTONE H3 ACETYLATION (AC-H3) STATUS IN THE NRF2 PROMOTER REGION, RESPECTIVELY. THE RESULTS SHOWED THAT SFN REDUCED ANG II-INDUCED CPG HYPERMETHYLATION AND PROMOTED AC-H3 ACCUMULATION IN THE NRF2 PROMOTER REGION, ACCOMPANIED BY THE INHIBITION OF GLOBAL DNMT AND HDAC ACTIVITY, AND A DECREASED PROTEIN EXPRESSION OF KEY DNMT AND HDAC ENZYMES. TAKEN TOGETHER, SFN EXERTS ITS CARDIOPROTECTIVE EFFECT THROUGH EPIGENETIC MODIFICATION OF NRF2, WHICH MAY PARTIALLY CONTRIBUTE TO LONG-TERM ACTIVATION OF CARDIAC NRF2. 2021 8 1320 51 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 9 2750 42 EXPRESSION LEVELS OF THE TYROSINE HYDROXYLASE GENE AND HISTONE MODIFICATIONS AROUND ITS PROMOTER IN THE LOCUS COERULEUS AND VENTRAL TEGMENTAL AREA OF RATS DURING FORCED ABSTINENCE FROM MORPHINE. BACKGROUND: EPIGENETIC MECHANISMS SUCH AS HISTONE MODIFICATIONS MAY BE INVOLVED IN THE STRUCTURAL AND BEHAVIORAL CHANGES ASSOCIATED WITH ADDICTION. WE STUDIED WHETHER MORPHINE-INDUCED CHANGES IN MRNA LEVELS OF THE CATECHOLAMINE BIOSYNTHESIS ENZYME, TYROSINE HYDROXYLASE (TH), ARE ASSOCIATED WITH HISTONE MODIFICATIONS AROUND THE PROMOTER OF THIS GENE IN THE LOCUS COERULEUS (LC) AND VENTRAL TEGMENTAL AREA (VTA) OF RATS. METHODS: DEPENDENCE WAS INDUCED IN RATS BY INTRAPERITONEAL INJECTIONS OF MORPHINE FOR 11 DAYS. THE ANIMALS WERE KILLED 2 H (CHRONIC MORPHINE), 24 H AND 7 DAYS (SPONTANEOUS WITHDRAWAL) AFTER THE LAST INJECTION OF MORPHINE. RESULTS: ANALYSIS OF OUR REAL-TIME QUANTITATIVE REVERSE TRANSCRIPTION PCR RESULTS BY 1-WAY ANOVA SHOWED SIGNIFICANT UPREGULATION (5.13 +/- 0.39 FOLDS) OF LC LEVELS OF THE TH TRANSCRIPT 24 H AFTER THE LAST INJECTION OF MORPHINE TO RATS, WHEN COMPARED WITH 2 H AND 7 DAYS TIME POINTS. CHRONIC MORPHINE AND MORPHINE ABSTINENCE FAILED TO CAUSE ANY SIGNIFICANT CHANGES IN THE LEVELS OF TH MRNA IN THE VTA AFTER CESSATION OF MORPHINE. CONSISTENTLY, CHROMATIN IMMUNOPRECIPITATION REAL-TIME QUANTITATIVE PCR ASSAYS REVEALED THAT 24 H AFTER THE LAST INJECTION OF MORPHINE, LEVELS OF H3 ACETYLATION WERE SIGNIFICANTLY INCREASED (4.12 +/- 0.38 FOLDS) AT THE PROMOTER OF THE TH GENE IN THE LC BUT NOT IN THE VTA. OUR DATA ALSO SHOWED THAT HISTONE H3 TRIMETHYLATION FAILED TO CHANGE AROUND THE TH GENE PROMOTER EITHER IN THE VTA OR IN THE LC AFTER MORPHINE ABSTINENCE. CONCLUSIONS: RESULTS OF THE PRESENT STUDY, FOR THE FIRST TIME, DEMONSTRATE THE INVOLVEMENT OF HISTONE H3 ACETYLATION IN THE REGULATION OF TH GENE EXPRESSION IN THE LC OF RATS DURING FORCED ABSTINENCE FROM MORPHINE. 2018 10 1800 26 EFFECT OF HISTONE DEACETYLASE INHIBITOR ON ETHANOL WITHDRAWAL-INDUCED HYPERALGESIA IN RATS. BACKGROUND: INCREASED PAIN SENSITIVITY IS OBSERVED FOLLOWING ALCOHOL WITHDRAWAL, AND ATTEMPTS TO ALLEVIATE THIS HYPERALGESIA CAN CONTRIBUTE TO THE CYCLE OF ADDICTION. THE AIM OF THIS STUDY WAS TO DETERMINE IF ALCOHOL WITHDRAWAL-INDUCED HYPERALGESIA WAS OBSERVED IN A CHRONIC ETHANOL EXPOSURE MODEL AND IF THIS PAIN WAS AFFECTED BY HISTONE DEACETYLASE INHIBITORS, THUS REVEALING AN EPIGENETIC MECHANISM. METHODS: ADULT MALE SPRAGUE DAWLEY RATS RECEIVED LIEBER-DECARLI LIQUID CONTROL OR ETHANOL (9% V/V) DIET FOR 15 DAYS. MECHANICAL SENSITIVITY WAS MEASURED WITH VON FREY HAIR STIMULATION OF THE HINDPAW DURING ETHANOL ADMINISTRATION AND 24- AND 72-HOUR WITHDRAWAL. RESULTS: ETHANOL WITHDRAWAL PRODUCED SEVERE AND SUSTAINED MECHANICAL HYPERALGESIA, AN EFFECT NOT OBSERVED IN THE CONTROL OR ETHANOL-MAINTAINED GROUPS. FURTHERMORE, THIS HYPERALGESIA WAS ATTENUATED BY THE HISTONE DEACETYLASE INHIBITOR, SUBEROYLANILIDE HYDROXAMIC ACID TREATMENT. CONCLUSIONS: HEIGHTENED PAIN SENSITIVITY WAS OBSERVED FOLLOWING WITHDRAWAL FROM CHRONIC ETHANOL EXPOSURE, AND HISTONE DEACETYLASE INHIBITORS COULD BE NOVEL TREATMENTS FOR THIS ALCOHOL WITHDRAWAL-INDUCED HYPERALGESIA. 2019 11 1831 43 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 12 1631 43 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 13 3082 45 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 14 3869 31 JNK1 REGULATES HISTONE ACETYLATION IN TRIGEMINAL NEURONS FOLLOWING CHEMICAL STIMULATION. TRIGEMINAL NERVE FIBERS IN NASAL AND ORAL CAVITIES ARE SENSITIVE TO VARIOUS ENVIRONMENTAL HAZARDOUS STIMULI, WHICH TRIGGER MANY NEUROTOXIC PROBLEMS SUCH AS CHRONIC MIGRAINE HEADACHE AND TRIGEMINAL IRRITATED DISORDERS. HOWEVER, THE ROLE OF JNK KINASE CASCADE AND ITS EPIGENETIC MODULATION OF HISTONE REMODELING IN TRIGEMINAL GANGLION (TG) NEURONS ACTIVATED BY ENVIRONMENTAL NEUROTOXINS REMAINS UNKNOWN. HERE WE INVESTIGATED THE ROLE OF JNK/C-JUN CASCADE IN THE REGULATION OF ACETYLATION OF H3 HISTONE IN TG NEURONS FOLLOWING IN VITRO STIMULATION BY A NEURO-INFLAMMATORY AGENT, MUSTARD OIL (MO). WE FOUND THAT MO STIMULATION ELICITED JNK/C-JUN PATHWAY SIGNIFICANTLY BY ENHANCING PHOSPHO-JNK1, PHOSPHO-C-JUN EXPRESSION, AND C-JUN ACTIVITY, WHICH WERE CORRELATED WITH AN ELEVATED ACETYLATED H3 HISTONE IN TG NEURONS. HOWEVER, INCREASES IN PHOSPHO-C-JUN AND C-JUN ACTIVITY WERE SIGNIFICANTLY BLOCKED BY A JNK INHIBITOR, SP600125. WE ALSO FOUND THAT ALTERED H3 HISTONE REMODELING, ASSESSED BY H3 ACETYLATION IN TRIGGERED TG NEURONS, WAS REDUCED BY SP600125. THE STUDY SUGGESTS THAT THE ACTIVATED JNK SIGNALING IN REGULATION OF HISTONE REMODELING MAY CONTRIBUTE TO NEURO-EPIGENTIC CHANGES IN PERIPHERAL SENSORY NEURONS FOLLOWING ENVIRONMENTAL NEUROTOXIC EXPOSURE. 2008 15 2590 35 EPIGENETICS OF PROTEASOME INHIBITION IN THE LIVER OF RATS FED ETHANOL CHRONICALLY. AIM: TO EXAMINE THE EFFECTS OF ETHANOL-INDUCED PROTEASOME INHIBITION, AND THE EFFECTS OF PROTEASOME INHIBITION IN THE REGULATION OF EPIGENETIC MECHANISMS. METHODS: RATS WERE FED ETHANOL FOR 1 MO USING THE TSUKAMOTO-FRENCH MODEL AND WERE COMPARED TO RATS GIVEN THE PROTEASOME INHIBITOR PS-341 (BORTEZOMIB, VELCADE(TM)) BY INTRAPERITONEAL INJECTION. MICROARRAY ANALYSIS AND REAL TIME PCR WERE PERFORMED AND PROTEASOME ACTIVITY ASSAYS AND WESTERN BLOT ANALYSIS WERE PERFORMED USING ISOLATED NUCLEI. RESULTS: CHRONIC ETHANOL FEEDING CAUSED A SIGNIFICANT INHIBITION OF THE UBIQUITIN PROTEASOME PATHWAY IN THE NUCLEUS, WHICH LED TO CHANGES IN THE TURNOVER OF TRANSCRIPTIONAL FACTORS, HISTONE-MODIFYING ENZYMES, AND, THEREFORE, AFFECTED EPIGENETIC MECHANISMS. CHRONIC ETHANOL FEEDING WAS RELATED TO AN INCREASE IN HISTONE ACETYLATION, AND IT IS HYPOTHESIZED THAT THE PROTEASOME PROTEOLYTIC ACTIVITY REGULATED HISTONE MODIFICATIONS BY CONTROLLING THE STABILITY OF HISTONE MODIFYING ENZYMES, AND, THEREFORE, REGULATED THE CHROMATIN STRUCTURE, ALLOWING EASY ACCESS TO CHROMATIN BY RNA POLYMERASE, AND, THUS, PROPER GENE EXPRESSION. PROTEASOME INHIBITION BY PS-341 INCREASED HISTONE ACETYLATION SIMILAR TO CHRONIC ETHANOL FEEDING. IN ADDITION, PROTEASOME INHIBITION CAUSED DRAMATIC CHANGES IN HEPATIC REMETHYLATION REACTIONS AS THERE WAS A SIGNIFICANT DECREASE IN THE ENZYMES RESPONSIBLE FOR THE REGENERATION OF S-ADENOSYLMETHIONINE, AND, IN PARTICULAR, A SIGNIFICANT DECREASE IN THE BETAINE-HOMOCYSTEINE METHYLTRANSFERASE ENZYME. THIS SUGGESTED THAT HYPOMETHYLATION WAS ASSOCIATED WITH PROTEASOME INHIBITION, AS INDICATED BY THE DECREASE IN HISTONE METHYLATION. CONCLUSION: THE ROLE OF PROTEASOME INHIBITION IN REGULATING EPIGENETIC MECHANISMS, AND ITS LINK TO LIVER INJURY IN ALCOHOLIC LIVER DISEASE, IS THUS A PROMISING APPROACH TO STUDY LIVER INJURY DUE TO CHRONIC ETHANOL CONSUMPTION. 2009 16 1632 27 DNMTS ARE INVOLVED IN TGF-BETA1-INDUCED EPITHELIAL-MESENCHYMAL TRANSITIONS IN AIRWAY EPITHELIAL CELLS. CHRONIC RHINOSINUSITIS (CRS) PATHOGENESIS IS CLOSELY RELATED TO TISSUE REMODELING, INCLUDING EPITHELIAL-MESENCHYMAL TRANSITION (EMT). EPIGENETIC MECHANISMS PLAY KEY ROLES IN EMT. DNA METHYLATION, MEDIATED BY DNA METHYLTRANSFERASES (DNMTS), IS AN EPIGENETIC MARKER THAT IS CRITICAL TO EMT. THE GOAL OF THIS STUDY WAS TO DETERMINE WHETHER DNMTS WERE INVOLVED IN TGF-BETA1-INDUCED EMT AND ELUCIDATE THE UNDERLYING MECHANISMS IN NASAL EPITHELIAL CELLS AND AIR-LIQUID INTERFACE CULTURES. GLOBAL DNA METHYLATION AND DNMT ACTIVITY WERE QUANTIFIED. DNMT EXPRESSION WAS MEASURED USING REAL-TIME PCR (QRT-PCR) IN HUMAN CRS TISSUES. MRNA AND PROTEIN LEVELS OF DNMTS, E-CADHERIN, VIMENTIN, ALPHA-SMA, AND FIBRONECTIN WERE DETERMINED USING RT-PCR AND WESTERN BLOTTING, RESPECTIVELY. DNMT1, DNMT3A, AND DNMT3B GENE EXPRESSION WERE KNOCKED DOWN USING SIRNA TRANSFECTION. MAPK PHOSPHORYLATION AND EMT-RELATED TRANSCRIPTION FACTOR LEVELS WERE DETERMINED USING WESTERN BLOTTING. SIGNALING PATHWAYS WERE ANALYZED USING SPECIFIC INHIBITORS OF MAPK. WE DEMONSTRATED THESE DATA IN PRIMARY NASAL EPITHELIAL CELLS AND AIR-LIQUID INTERFACE CULTURES. GLOBAL DNA METHYLATION, DNMT ACTIVITY, AND DNMT EXPRESSION INCREASED IN CRS TISSUES. DNMT EXPRESSION WAS POSITIVELY CORRELATED WITH LUND-MCKAY CT SCORES. TGF-BETA1 DOSE-DEPENDENTLY INDUCED DNMT EXPRESSION. FURTHER, 5-AZA INHIBITED TGF-BETA1-INDUCED DNMT, SNAIL, AND SLUG EXPRESSION RELATED TO EMT, AS WELL AS P38 AND JNK PHOSPHORYLATION IN A549 CELLS AND TGF-BETA1-INDUCED DNMT EXPRESSION AND EMT IN PRIMARY NASAL EPITHELIAL CELLS AND AIR-LIQUID INTERFACE CULTURES. TGF-BETA1-INDUCED DNMT EXPRESSION LEADS TO DNA METHYLATION AND EMT VIA P38, JNK, SNAIL, AND SLUG SIGNALING PATHWAYS. INHIBITION OF DNMT SUPPRESSED THE EMT PROCESS AND THEREFORE IS POTENTIALLY A CRS THERAPEUTIC STRATEGY. 2022 17 4906 44 P300 EXERTS AN EPIGENETIC ROLE IN CHRONIC NEUROPATHIC PAIN THROUGH ITS ACETYLTRANSFERASE ACTIVITY IN RATS FOLLOWING CHRONIC CONSTRICTION INJURY (CCI). BACKGROUND: NEUROPATHIC PAIN IS DETRIMENTAL TO HUMAN HEALTH; HOWEVER, ITS PATHOGENESIS STILL REMAINS LARGELY UNKNOWN. OVEREXPRESSION OF PAIN-ASSOCIATED GENES AND INCREASED NOCICEPTIVE SOMATO-SENSITIVITY ARE WELL OBSERVED IN NEUROPATHIC PAIN. THE IMPORTANCE OF EPIGENETIC MECHANISMS IN REGULATING THE EXPRESSION OF PRO- OR ANTI-NOCICEPTIVE GENES HAS BEEN REVEALED BY STUDIES RECENTLY, AND WE HYPOTHESIZE THAT THE TRANSCRIPTIONAL COACTIVATOR AND THE HISTONE ACETYLTRANSFERASE E1A BINDING PROTEIN P300 (P300), AS A PART OF THE EPIGENETIC MECHANISMS OF GENE REGULATION, MAY BE INVOLVED IN THE PATHOGENESIS OF NEUROPATHIC PAIN INDUCED BY CHRONIC CONSTRICTION INJURY (CCI). TO TEST THIS HYPOTHESIS, TWO DIFFERENT APPROACHES WERE USED IN THIS STUDY: (I) DOWN-REGULATING P300 WITH SPECIFIC SMALL HAIRPIN RNA (SHRNA) AND (II) CHEMICAL INHIBITION OF P300 ACETYLTRANSFERASE ACTIVITY BY A SMALL MOLECULE INHIBITOR, C646. RESULTS: USING THE CCI RAT MODEL, WE FOUND THAT THE P300 EXPRESSION WAS INCREASED IN THE LUMBAR SPINAL CORD ON DAY 14 AFTER CCI. THE TREATMENT WITH INTRATHECAL P300 SHRNA REVERSED CCI-INDUCED MECHANICAL ALLODYNIA AND THERMAL HYPERALGESIA, AND SUPPRESSED THE EXPRESSION OF CYCLOOXYGENASE-2 (COX-2), A NEUROPATHIC PAIN-ASSOCIATED FACTOR. FURTHERMORE, C646, AN INHIBITOR OF P300 ACETYLTRANSFERASE, ALSO ATTENUATED MECHANICAL ALLODYNIA AND THERMAL HYPERALGESIA, ACCOMPANIED BY A SUPPRESSED COX-2 EXPRESSION, IN THE SPINAL CORD. CONCLUSIONS: THE RESULTS SUGGEST THAT, THROUGH ITS ACETYLTRANSFERASE ACTIVITY IN THE SPINAL CORD AFTER CCI, P300 EPIGENETICALLY PLAYS AN IMPORTANT ROLE IN NEUROPATHIC PAIN. INHIBITING P300, USING INTERFERING RNA OR C646, MAY BE A PROMISING APPROACH TO THE DEVELOPMENT OF NEW NEUROPATHIC PAIN THERAPIES. 2012 18 4899 27 OXIDATIVE STRESS MEDIATES THE APOPTOSIS AND EPIGENETIC MODIFICATION OF THE BCL-2 PROMOTER VIA DNMT1 IN A CIGARETTE SMOKE-INDUCED EMPHYSEMA MODEL. BACKGROUND: EMPHYSEMA IS A CRUCIAL PATHOLOGICAL CHARACTERISTIC OF CHRONIC OBSTRUCTIVE PULMONARY DISEASE (COPD). OXIDATIVE STRESS, APOPTOSIS AND EPIGENETIC MECHANISMS CONTRIBUTE TO THE PATHOGENESIS OF EMPHYSEMA. HOWEVER, AN ATTEMPT TO ACCURATELY IDENTIFY WHETHER THESE MECHANISMS INTERACT WITH EACH OTHER AND HOW THEY ARE TRIGGERED HAS NEVER BEEN CONDUCTED. METHOD: THE TOTAL REACTIVE OXYGEN SPECIES (ROS) LEVEL, PULMONARY APOPTOSIS AND B-CELL LYMPHOMA/LEUKEMIA-2 (BCL-2) EXPRESSION, AN APOPTOSIS REGULATOR, WERE DETECTED IN SAMPLES FROM COPD PATIENTS. BISULFITE SEQUENCING PCR (BSP) WAS CONDUCTED TO OBSERVE THE ALTERATIONS IN THE METHYLATION OF THE BCL-2 PROMOTER IN SPECIMENS. THE DYSREGULATION OF DNA METHYLTRANSFERASE ENZYME 1 (DNMT1), A VITAL DNA METHYLTRANSFERASE ENZYME, IN THE LUNGS OF PATIENTS WAS CONFIRMED THROUGH WESTERN BLOTTING. TO FIND OUT INTERACTIONS BETWEEN OXIDATIVE STRESS AND DNA METHYLATION IN EMPHYSEMA, MOUSE MODELS WERE BUILT WITH ANTIOXIDANT TREATMENT AND DNMT1 SILENCING, AND WERE EXAMINED WITH THE PULMONARY APOPTOSIS, BCL-2 AND DNMT1 LEVELS, AND EPIGENETIC ALTERATIONS OF BCL-2. RESULTS: HIGHER ROS LEVELS AND PULMONARY APOPTOSIS WERE OBSERVED IN COPD PATIENTS THAN IN HEALTHY CONTROLS. DOWNREGULATED BCL-2 EXPRESSION WITH INCREASED PROMOTER METHYLATION AND DNMT1 PROTEIN EXPRESSION WAS FOUND IN COPD PATIENTS. ANTIOXIDANT TREATMENT REDUCED THE LEVEL OF ROS, DNMT1 PROTEIN AND EMPHYSEMATOUS PROGRESSION IN THE SMOKING MODELS. FOLLOWING DNMT1 BLOCKADE, SMOKING MODELS SHOWED IMPROVED LUNG FUNCTION, PULMONARY APOPTOSIS, EMPHYSEMATOUS PROGRESSION, AND INCREASED BCL-2 PROTEIN LEVEL WITH LESS PROMOTER METHYLATION THAN EMPHYSEMA MICE. CONCLUSION: CIGARETTE-INDUCED OXIDATIVE STRESS MEDIATES PULMONARY APOPTOSIS AND HYPERMETHYLATION OF THE BCL-2 PROMOTER IN EMPHYSEMA MODELS THROUGH DNMT1. 2020 19 5417 34 REGULATION OF DNA METHYLATION IN RHEUMATOID ARTHRITIS SYNOVIOCYTES. RHEUMATOID ARTHRITIS (RA) IS A CHRONIC INFLAMMATORY DISEASE IN WHICH FIBROBLAST-LIKE SYNOVIOCYTES (FLS) EXHIBIT AN AGGRESSIVE PHENOTYPE. ALTHOUGH THE MECHANISMS RESPONSIBLE ARE NOT WELL DEFINED, EPIGENETIC DETERMINANTS SUCH AS DNA METHYLATION MIGHT CONTRIBUTE. DNA METHYLTRANSFERASES (DNMTS) ARE CRITICAL ENZYMES THAT ESTABLISH AND MAINTAIN DNA METHYLATION. WE EVALUATED WHETHER PROINFLAMMATORY CYTOKINES MIGHT CONTRIBUTE TO DIFFERENTIAL DNA METHYLATION PREVIOUSLY DESCRIBED IN RA FLS THROUGH ALTERED DNMT EXPRESSION. FLS WERE OBTAINED FROM RA AND OSTEOARTHRITIS (OA) SYNOVIUM AT THE TIME OF TOTAL JOINT REPLACEMENT. GENE EXPRESSION WAS DETERMINED BY QUANTITATIVE REAL-TIME PCR AND PROTEIN EXPRESSION BY WESTERN BLOT ANALYSIS. DNMT ACTIVITY WAS MEASURED WITH A FUNCTIONAL ASSAY, AND GLOBAL METHYLATION WAS DETERMINED BY AN IMMUNOASSAY THAT DETECTS METHYLCYTOSINE. RESTING EXPRESSION OF DNMT1, -3A, AND -3B MRNA WERE SIMILAR IN RA AND OA FLS. WESTERN BLOT SHOWED ABUNDANT DNMT1 AND DNMT3A PROTEIN. EXPOSURE TO IL-1 DECREASED DNMT1 AND DNMT3A MRNA EXPRESSION IN FLS. DOSE RESPONSES DEMONSTRATED DECREASED DNMT EXPRESSION AT CONCENTRATIONS AS LOW AS 1 PG/ML OF IL-1. DNMT MRNA LEVELS DECREASED RAPIDLY, WITH SIGNIFICANT SUPPRESSION AFTER 2-8 H OF IL-1 STIMULATION. IL-1 STIMULATION OF OA FLS DID NOT AFFECT METHYLATION OF LINE1 SITES BUT LED TO DEMETHYLATION OF A CHI3L1 LOCUS THAT IS HYPOMETHYLATED IN RA FLS. CHRONIC IL-1 STIMULATION ALSO MIMICKED THE EFFECT OF A DNMT INHIBITOR ON FLS GENE EXPRESSION. EXPOSURE TO PROINFLAMMATORY MEDIATORS REVERSIBLY ALTERS DNA METHYLATION IN FLS BY DECREASING DNMT EXPRESSION AND FUNCTION. THESE DATA SUGGEST THAT IL-1 CAN POTENTIALLY IMPRINT CELLS IN CHRONIC INFLAMMATORY DISEASES. 2013 20 6177 30 THE HISTONE METHYLTRANSFERASE G9A MEDIATES STRESS-REGULATED ALCOHOL DRINKING. THE EPIGENETIC ENZYME G9A IS A HISTONE METHYLTRANSFERASE THAT DIMETHYLATES LYSINE 9 ON HISTONE H3 (H3K9ME2), AND IN THE ADULT NUCLEUS ACCUMBENS (NAC), G9A REGULATES MULTIPLE BEHAVIORS ASSOCIATED WITH SUBSTANCE USE DISORDER. WE SHOW HERE THAT CHRONIC INTERMITTENT ETHANOL (CIE) EXPOSURE IN MALE MICE REDUCED BOTH G9A AND H3K9ME2 LEVELS IN THE ADULT NAC, BUT NOT DORSAL STRIATUM. VIRAL-MEDIATED REDUCTION OF G9A IN THE NAC HAD NO EFFECTS ON BASELINE VOLITIONAL ETHANOL DRINKING OR ESCALATED ALCOHOL DRINKING PRODUCED BY CIE EXPOSURE; HOWEVER, NAC G9A WAS REQUIRED FOR STRESS-REGULATED CHANGES IN ETHANOL DRINKING, INCLUDING POTENTIATED ALCOHOL DRINKING PRODUCED BY ACTIVATION OF THE KAPPA-OPIOID RECEPTOR. IN ADDITION, WE OBSERVED THAT CHRONIC SYSTEMIC ADMINISTRATION OF A G9A INHIBITOR, UNC0642, ALSO BLOCKED STRESS-POTENTIATED ALCOHOL DRINKING. TOGETHER, OUR FINDINGS SUGGEST THAT CHRONIC ALCOHOL USE, SIMILAR TO OTHER ABUSED SUBSTANCES, PRODUCES A NAC-SELECTIVE REDUCTION IN G9A LEVELS THAT SERVES TO LIMIT STRESS-REGULATED ALCOHOL DRINKING. MOREOVER, OUR FINDINGS SUGGEST THAT PHARMACOLOGICAL INHIBITION OF G9A MIGHT PROVIDE A NOVEL THERAPEUTIC APPROACH TO TREAT STRESS-INDUCED ALCOHOL DRINKING, WHICH IS A MAJOR TRIGGER OF RELAPSE IN INDIVIDUALS SUFFERING FROM AUD. 2022