1 2202 135 EPIGENETIC MODIFICATION OF MIR-10A REGULATES RENAL DAMAGE BY TARGETING CREB1 IN TYPE 2 DIABETES MELLITUS. EMERGING EVIDENCE HAS SHOWN THAT MICRORNA-MEDIATED GENE EXPRESSION MODULATION PLAYS A CRUCIAL ROLE IN THE PATHOGENESIS OF TYPE 2 DIABETES MELLITUS, BUT THE NOVEL MIRNAS INVOLVED IN TYPE 2 DIABETES AND ITS FUNCTIONAL REGULATORY MECHANISMS STILL NEED TO BE DETERMINED. IN THIS STUDY, WE ASSESSED THE ROLE OF MIR-10A IN EXTRACELLULAR MATRIX ACCUMULATION IN THE KIDNEY OF DIABETIC MELLITUS INDUCED BY COMBINING ADMINISTRATION OF CHRONIC HIGH FAT DIET (HFD) AND LOW DOSAGE OF STREPTOZOTOCIN (STZ, 35MG/KG). HERE, WE FOUND THAT HFD/STZ ADMINISTRATION DECREASED THE LEVEL OF MICRORNA (MIR-10A) EXPRESSION IN ICR STRAIN MICE. OVEREXPRESSION OF MIR-10A ALLEVIATED THE INCREASED RATIO OF URINE ALBUMIN-TO-CREATININE (ACR) RATIO OF HFD/STZ MICE. IN CONTRAST, KNOCKDOWN OF MIR-10A INCREASED THE RATIO OF KIDNEY ACR IN NAIVE MICE. FURTHERMORE, CAMP RESPONSE ELEMENT BINDING PROTEIN 1 (CREB1) WAS VALIDATED AS A TARGET OF MIR-10A IN VITRO AND IN VIVO. CREB1 AND ITS DOWNSTREAM FIBRONECTIN (FN, EXTRACELLULAR MATRIX) WERE INCREASED IN HFD/STZ-TREATED MICE, WHICH WAS REVERSED BY KIDNEY MIR-10A OVEREXPRESSION. THE CONTENT OF CREB1 AND FN WAS INCREASED BY MIR-10A KNOCKDOWN IN KIDNEY OF NAIVE MICE. FURTHERMORE, HISTONE DEACETYLASE 3 (HDAC3) WAS REVEALED TO BE INCREASED IN KIDNEY OF HFD/STZ MICE, ACCOMPANIED WITH THE AUGMENTATION OF ACR RATIO AND FN LEVEL. KNOCKDOWN OF HDAC3 WITH SIRNA SIGNIFICANTLY CAUSED THE INCREASE OF MIR-10A, RESULTING IN THE DECREASE IN CREB1 AND FN EXPRESSION IN KIDNEY OF HFD/STZ MICE. CONTRARILY, HDAC3 OVEREXPRESSION MEDIATED BY LENTIVIRUS DECREASED MIR-10A CONTENT, AND ENHANCED ACR VALUE, CREB1 AND FN FORMATION IN NAIVE MICE. COLLECTIVELY, THESE RESULTS ELUCIDATE THAT HDAC3/MIR-10A/CREB1 SERVES AS A NEW MECHANISM UNDERLYING KIDNEY INJURY, PROVIDING POTENTIAL THERAPEUTIC TARGETS IN TYPE 2 DIABETES. 2016 2 4366 44 MIRNA-23A/CXCR4 REGULATES NEUROPATHIC PAIN VIA DIRECTLY TARGETING TXNIP/NLRP3 INFLAMMASOME AXIS. BACKGROUND: CHEMOKINE CXC RECEPTOR 4 (CXCR4) IN SPINAL GLIAL CELLS HAS BEEN IMPLICATED IN NEUROPATHIC PAIN. HOWEVER, THE REGULATORY CASCADES OF CXCR4 IN NEUROPATHIC PAIN REMAIN ELUSIVE. HERE, WE INVESTIGATED THE FUNCTIONAL REGULATORY ROLE OF MIRNAS IN THE PAIN PROCESS AND ITS INTERPLAY WITH CXCR4 AND ITS DOWNSTREAM SIGNALING. METHODS: MIRNAS AND CXCR4 AND ITS DOWNSTREAM SIGNALING MOLECULES WERE MEASURED IN THE SPINAL CORDS OF MICE WITH SCIATIC NERVE INJURY VIA PARTIAL SCIATIC NERVE LIGATION (PSNL). IMMUNOBLOTTING, IMMUNOFLUORESCENCE, IMMUNOPRECIPITATION, AND MAMMAL TWO-HYBRID AND BEHAVIORAL TESTS WERE USED TO EXPLORE THE DOWNSTREAM CXCR4-DEPENDENT SIGNALING PATHWAY. RESULTS: CXCR4 EXPRESSION INCREASED IN SPINAL GLIAL CELLS OF MICE WITH PSNL-INDUCED NEUROPATHIC PAIN. BLOCKING CXCR4 ALLEVIATED THE PAIN BEHAVIOR; CONTRARILY, OVEREXPRESSING CXCR4 INDUCED PAIN HYPERSENSITIVITY. MICRORNA-23A-3P (MIR-23A) DIRECTLY BOUNDS TO 3' UTR OF CXCR4 MRNA. PSNL-INDUCED NEUROPATHIC PAIN SIGNIFICANTLY REDUCED MRNA EXPRESSION OF MIR-23A. OVEREXPRESSION OF MIR-23A BY INTRATHECAL INJECTION OF MIR-23A MIMICS OR LENTIVIRUS REDUCED SPINAL CXCR4 AND PREVENTED PSNL-INDUCED NEUROPATHIC PAIN. IN CONTRAST, KNOCKDOWN OF MIR-23A BY INTRATHECAL INJECTION OF MIR-23A INHIBITOR OR LENTIVIRUS INDUCED PAIN-LIKE BEHAVIOR, WHICH WAS REDUCED BY CXCR4 INHIBITION. ADDITIONALLY, MIR-23A KNOCKDOWN OR CXCR4 OVEREXPRESSION IN NAIVE MICE COULD INCREASE THE THIOREDOXIN-INTERACTING PROTEIN (TXNIP), WHICH WAS ASSOCIATED WITH INDUCTION OF NOD-LIKE RECEPTOR PROTEIN 3 (NLRP3) INFLAMMASOME. INDEED, CXCR4 AND TXNIP WERE CO-EXPRESSED. THE MAMMAL TWO-HYBRID ASSAY REVEALED THE DIRECT INTERACTION BETWEEN CXCR4 AND TXNIP, WHICH WAS INCREASED IN THE SPINAL CORD OF PSNL MICE. IN PARTICULAR, INHIBITION OF TXNIP REVERSED PAIN BEHAVIOR ELICITED BY PSNL, MIR-23A KNOCKDOWN, OR CXCR4 OVEREXPRESSION. MOREOVER, MIR-23A OVEREXPRESSION OR CXCR4 KNOCKDOWN INHIBITED THE INCREASE OF TXNIP AND NLRP3 INFLAMMASOME IN PSNL MICE. CONCLUSIONS: MIR-23A, BY DIRECTLY TARGETING CXCR4, REGULATES NEUROPATHIC PAIN VIA TXNIP/NLRP3 INFLAMMASOME AXIS IN SPINAL GLIAL CELLS. EPIGENETIC INTERVENTIONS AGAINST MIR-23A, CXCR4, OR TXNIP MAY POTENTIALLY SERVE AS NOVEL THERAPEUTIC AVENUES IN TREATING PERIPHERAL NERVE INJURY-INDUCED NOCICEPTIVE HYPERSENSITIVITY. 2018 3 6429 43 THE UPREGULATION OF NLRP3 INFLAMMASOME IN DORSAL ROOT GANGLION BY TEN-ELEVEN TRANSLOCATION METHYLCYTOSINE DIOXYGENASE 2 (TET2) CONTRIBUTED TO DIABETIC NEUROPATHIC PAIN IN MICE. BACKGROUND: THE NUCLEOTIDE OLIGOMERIZATION DOMAIN (NOD)-LIKE RECEPTOR FAMILY PYRIN DOMAIN CONTAINING 3 (NLRP3) IN DORSAL ROOT GANGLION (DRG) CONTRIBUTES TO PAIN HYPERSENSITIVITY IN MULTIPLE NEUROPATHIC PAIN MODELS, BUT THE FUNCTION OF THE NLRP3 IN DIABETIC NEUROPATHIC PAIN (DNP) AND THE REGULATION MECHANISM ARE STILL LARGELY UNKNOWN. EPIGENETIC REGULATION PLAYS A VITAL ROLE IN THE CONTROLLING OF GENE EXPRESSION. TEN-ELEVEN TRANSLOCATION METHYLCYTOSINE DIOXYGENASE 2 (TET2) IS A DNA DEMETHYLASE THAT CONTRIBUTES TO TRANSCRIPTIONAL ACTIVATION. TET2 IS ALSO INVOLVED IN HIGH GLUCOSE (HG)-INDUCED PATHOLOGY. METHODS: DNP WAS INDUCED IN MICE VIA THE INTRAPERITONEAL INJECTION OF STREPTOZOTOCIN (STZ) FOR FIVE CONSECUTIVE DAYS AND THE MECHANICAL THRESHOLD WAS EVALUATED IN STZ-DIABETIC MICE BY USING VON FREY HAIRS. THE EXPRESSION LEVEL OF THE NLRP3 PATHWAY AND TET2 IN DRG WERE DETERMINED THROUGH MOLECULAR BIOLOGY EXPERIMENTS. THE REGULATION OF THE NLRP3 PATHWAY BY TET2 WAS EXAMINED IN IN VITRO AND IN VIVO CONDITIONS. RESULTS: IN THE PRESENT RESEARCH, WE FIRST ESTABLISHED THE DNP MODEL AND FOUND THAT NLRP3 PATHWAY WAS ACTIVATED IN DRG. THE TREATMENT OF NLRP3 INHIBITOR MCC950 ALLEVIATED THE MECHANICAL ALLODYNIA OF DNP MICE. THEN WE REVEALED THAT IN STZ-DIABETIC MICE DRG, THE GENOMIC DNA WAS DEMETHYLATED, AND THE EXPRESSION OF DNA DEMETHYLASE TET2 WAS INCREASED EVIDENTLY. USING RNA-SEQUENCING ANALYSIS, WE FOUND THAT THE EXPRESSION OF TXNIP, A GENE THAT ENCODES A THIOREDOXIN-INTERACTING PROTEIN (TXNIP) WHICH MEDIATES NLRP3 ACTIVATION, WAS ELEVATED IN THE DRG AFTER STZ TREATMENT. IN ADDITION, KNOCKING DOWN OF TET2 EXPRESSION IN DRG USING TET2-SIRNA SUPPRESSED THE MRNA EXPRESSION OF TXNIP AND SUBSEQUENTLY INHIBITED THE EXPRESSION/ACTIVATION OF NLRP3 INFLAMMASOME IN VITRO AND IN VIVO AS WELL AS RELIEVED THE PAIN SENSITIVITY OF DNP ANIMALS. CONCLUSION: THE RESULTS SUGGESTED THAT THE UPREGULATION OF THE TXNIP/NLRP3 PATHWAY BY TET2 IN DRG WAS INVOLVED IN THE PAIN HYPERSENSITIVITY OF THE DNP MODEL. 2022 4 423 41 ANRIL REGULATES MULTIPLE MOLECULES OF PATHOGENETIC SIGNIFICANCE IN DIABETIC NEPHROPATHY. BACKGROUND: HYPERGLYCEMIA-INDUCED TRANSCRIPTIONAL ALTERATIONS LEAD TO ABERRANT SYNTHESIS OF A LARGE NUMBER OF PATHOGENETIC MOLECULES LEADING TO FUNCTIONAL AND STRUCTURAL DAMAGE TO MULTIPLE END ORGANS INCLUDING THE KIDNEYS. DIABETIC NEPHROPATHY (DN) REMAINS A MAJOR CAUSE OF END STAGE RENAL DISEASE. MULTIPLE EPIGENETIC MECHANISMS, INCLUDING ALTERATION OF LONG NON-CODING RNAS (LNCRNAS) MAY PLAY A SIGNIFICANT ROLE MEDIATING THE CELLULAR TRANSCRIPTIONAL ACTIVITIES. WE HAVE PREVIOUSLY SHOWN THAT LNCRNA ANRIL MAY MEDIATE DIABETES ASSOCIATED MOLECULAR, FUNCTIONAL AND STRUCTURAL ABNORMALITIES IN DN. HERE WE EXPLORED DOWNSTREAM MECHANISMS OF ANRIL ALTERATION IN DN. METHODS: WE USED RENAL CORTICAL TISSUES FROM ANRIL KNOCKOUT (KO) MICE AND WILD TYPE (WT) MICE, WITH OR WITHOUT STREPTOZOTOCIN (STZ) INDUCED DIABETES FOR RNA SEQUENCING. THE DIFFERENTIALLY EXPRESSED GENES WERE IDENTIFIED USING EDGER AND DESEQ2 COMPUTATIONAL METHODS. KEGG AND REACTOME PATHWAY ANALYSES AND NETWORK ANALYSES USING STRING AND IPA WERE SUBSEQUENTLY PERFORMED. RESULTS: DIABETIC ANIMALS SHOWED HYPERGLYCEMIA, REDUCED BODY WEIGHT GAIN, POLYURIA AND INCREASED URINARY ALBUMIN. BOTH ALBUMINURIA AND POLYURIA WERE CORRECTED IN THE KO DIABETIC MICE. RNA ANALYSES SHOWED DIABETES INDUCED ALTERATIONS OF A LARGE NUMBER OF TRANSCRIPTS IN THE WILD TYPE (WT) ANIMALS. ANRIL KNOCKOUT (KO) PREVENTED A LARGE NUMBER OF SUCH ALTERATIONS. THE ALTERED TRANSCRIPTS INCLUDE METABOLIC PATHWAYS, APOPTOSIS, EXTRACELLULAR MATRIX PROTEIN SYNTHESIS AND DEGRADATION, NFKB RELATED PATHWAYS, AGE-RAGE INTERACTION PATHWAYS ETC. ANRIL KO PREVENTED MAJORITY OF THESE PATHWAYS. CONCLUSION: THESE FINDINGS SUGGEST THAT AS ANRIL REGULATES A LARGE NUMBER OF MOLECULES OF PATHOGENETIC SIGNIFICANCE, IT MAY POTENTIALLY BE A DRUG TARGET FOR DN AND OTHER CHRONIC DIABETIC COMPLICATIONS. 2022 5 5296 32 PROTECTIVE ROLE OF SODIUM BUTYRATE, A HDAC INHIBITOR ON BETA-CELL PROLIFERATION, FUNCTION AND GLUCOSE HOMEOSTASIS THROUGH MODULATION OF P38/ERK MAPK AND APOPTOTIC PATHWAYS: STUDY IN JUVENILE DIABETIC RAT. TYPE 1 DIABETES (T1D) ALSO KNOWN AS JUVENILE DIABETES IS A CHRONIC AUTOIMMUNE DISORDER THAT PRECIPITATES IN GENETICALLY SUSCEPTIBLE INDIVIDUALS BY ENVIRONMENTAL FACTORS PARTICULARLY DURING EARLY AGE. BOTH GENETIC AND EPIGENETIC FACTORS ARE IMPLICATED IN THE BETA-CELL DEVELOPMENT, PROLIFERATION, DIFFERENTIATION AND FUNCTION. RECENT EVIDENCES SUGGESTED THAT THERE IS A LINK BETWEEN DIABETES AND HISTONE DEACETYLASES (HDACS), BECAUSE HDAC INHIBITORS PROMOTE BETA-CELL DEVELOPMENT, PROLIFERATION AND FUNCTION AS WELL AS IMPROVE GLUCOSE HOMEOSTASIS. SODIUM BUTYRATE (NAB) IS A SHORT CHAIN FATTY ACID HAVING HDAC INHIBITION ACTIVITY. THE PRESENT STUDY WAS AIMED TO INVESTIGATE THE PROTECTIVE ROLE OF NAB TREATMENT ON THE BETA-CELL PROLIFERATION, FUNCTION AND GLUCOSE HOMEOSTASIS AS WELL AS APOPTOSIS IN JUVENILE DIABETIC RAT. DIABETES WAS INDUCED BY SINGLE INJECTION OF STZ (60 MG/KG, I.P.) IN CHILLED CITRATE BUFFER, WHILE NAB (500 MG/KG/DAY) WAS ADMINISTRATED BY I.P. ROUTE FOR 21 DAYS AS PRE- AND POST-TREATMENT SCHEDULE. PLASMA GLUCOSE AND INSULIN LEVELS, HBA1C, GLUCOSE TOLERANCE, APOPTOSIS, AND EXPRESSION OF PROLIFERATING CELL NUCLEAR ANTIGEN (PCNA), P38, P53, CASPASE-3, EXTRACELLULAR SIGNAL-REGULATED KINASE-1/2 (ERK-1/2), FORKHEAD BOX PROTEIN O1 (FOXO1) AND INSULIN RECEPTOR SUBSTRATE-1 (IRS-1) AS WELL AS HISTONE ACETYLATION WERE EVALUATED. NAB TREATMENT DECREASED PLASMA GLUCOSE, HBA1C, BETA-CELL APOPTOSIS AND IMPROVED PLASMA INSULIN LEVEL AND GLUCOSE HOMEOSTASIS THROUGH HDAC INHIBITION AND HISTONE ACETYLATION IN DIABETIC ANIMAL AS COMPARED TO CONTROL. NAB TREATMENT IMPROVED THE BETA-CELL PROLIFERATION, FUNCTION AND GLUCOSE HOMEOSTASIS AS WELL AS REDUCED BETA-CELL APOPTOSIS IN JUVENILE DIABETIC RAT BY THE MODULATION OF P38/ERK MAPK AND APOPTOTIC PATHWAY. 2014 6 868 28 CHRONIC ADVANCED-GLYCATION END PRODUCTS TREATMENT INDUCES TXNIP EXPRESSION AND EPIGENETIC CHANGES IN GLOMERULAR PODOCYTES IN VIVO AND IN VITRO. ADVANCED GLYCATION END PRODUCTS (AGES) PLAY AN IMPORTANT ROLE IN OXIDATIVE STRESS AND INFLAMMATION, PROCESSES IMPLICATED IN THE DEVELOPMENT AND PROGRESSION OF KIDNEY DYSFUNCTION. IN THE PRESENT STUDY, WE INVESTIGATED THE PARTICIPATION OF THE PRO-OXIDANT PROTEIN THIOREDOXIN-INTERACTING PROTEIN (TXNIP) AND OF EPIGENETIC MECHANISMS ON KIDNEY TISSUE (IN VIVO, IN NON-DIABETIC RATS) AND ON TERMINALLY DIFFERENTIATED GLOMERULAR PODOCYTES (IN VITRO) CHRONICALLY EXPOSED TO AGES. AGES INDUCED TOTAL KIDNEY AND GLOMERULAR TXNIP EXPRESSION AND DECREASED H3K27ME3 CONTENT. CONCOMITANT TREATMENT WITH THE ANTIOXIDANT N-ACETYL-CYSTEINE (NAC) REVERSED ONLY THE INCREASED TXNIP EXPRESSION. TXNIP EXPRESSION POSITIVELY CORRELATED WITH PROTEINURIA AND NEGATIVELY CORRELATED WITH H3K27ME3 CONTENT. IN VITRO STUDIES IN PODOCYTES SHOWED THAT 72 H EXPOSURE TO AGES DECREASED NEPHRIN EXPRESSION AND INCREASED TXNIP, NOX4, COL4A1, AND EPITHELIAL-TO-MESENCHYMAL TRANSITION (EMT) MARKERS (ACTA2, SNAIL1, AND TGFB1). PODOCYTES TREATMENT WITH NAC REVERSED NOX4, COL4A1, ACTA2, AND TGFB1 INCREASED EXPRESSION BUT DID NOT ABROGATE THE REDUCED EXPRESSION OF NEPHRIN. MIR-29A EXPRESSION WAS DOWNREGULATED BY AGES IN VIVO, BUT NOT IN VITRO. IN CONCLUSION, TREATMENT OF NON-DIABETIC RATS WITH AGES INDUCED TXNIP EXPRESSION AND DECREASED THE CONTENTS OF THE REPRESSIVE EPIGENETIC MARK H3K27ME3 AND OF MIR-29A, POTENTIALLY DRIVING INJURY TO GLOMERULAR FILTRATION BARRIER AND PODOCYTES DYSFUNCTION. 2021 7 6453 26 THIOREDOXIN INTERACTING PROTEIN (TXNIP) INDUCES INFLAMMATION THROUGH CHROMATIN MODIFICATION IN RETINAL CAPILLARY ENDOTHELIAL CELLS UNDER DIABETIC CONDITIONS. CHRONIC HYPERGLYCEMIA AND ACTIVATION OF RECEPTOR FOR ADVANCED GLYCATION END PRODUCTS (RAGE) ARE KNOWN RISK FACTORS FOR MICROVASCULAR DISEASE DEVELOPMENT IN DIABETIC RETINOPATHY. THIOREDOXIN-INTERACTING PROTEIN (TXNIP), AN ENDOGENOUS INHIBITOR OF ANTIOXIDANT THIOREDOXIN (TRX), PLAYS A CAUSATIVE ROLE IN DIABETES AND ITS VASCULAR COMPLICATIONS. HEREIN WE INVESTIGATE WHETHER HG AND RAGE INDUCE INFLAMMATION IN RAT RETINAL ENDOTHELIAL CELLS (EC) UNDER DIABETIC CONDITIONS IN CULTURE THROUGH TXNIP ACTIVATION AND WHETHER EPIGENETIC MECHANISMS PLAY A ROLE IN INFLAMMATORY GENE EXPRESSION. WE SHOW THAT RAGE ACTIVATION BY ITS LIGAND S100B OR HG TREATMENT OF RETINAL EC INDUCES THE EXPRESSION OF TXNIP AND INFLAMMATORY GENES SUCH AS COX2, VEGF-A, AND ICAM1. TXNIP SILENCING BY SIRNA IMPEDES RAGE AND HG EFFECTS WHILE STABLE OVER-EXPRESSION OF A CDNA FOR HUMAN TXNIP IN EC ELEVATES INFLAMMATION. P38 MAPK-NF-KAPPAB SIGNALING PATHWAY AND HISTONE H3 LYSINE (K) NINE MODIFICATIONS ARE INVOLVED IN TXNIP-INDUCED INFLAMMATION. CHROMATIN IMMUNOPRECIPITATION (CHIP) ASSAYS REVEAL THAT TXNIP OVER-EXPRESSION IN EC ABOLISHES H3K9 TRI-METHYLATION, A MARKER FOR GENE INACTIVATION, AND INCREASES H3K9 ACETYLATION, AN INDICATOR OF GENE INDUCTION, AT PROXIMAL COX2 PROMOTER BEARING THE NF-KAPPAB-BINDING SITE. THESE FINDINGS HAVE IMPORTANT IMPLICATIONS TOWARD UNDERSTANDING THE MOLECULAR MECHANISMS OF OCULAR INFLAMMATION AND ENDOTHELIAL DYSFUNCTION IN DIABETIC RETINOPATHY. 2009 8 2452 39 EPIGENETIC SUPPRESSION OF POTASSIUM-CHLORIDE CO-TRANSPORTER 2 EXPRESSION IN INFLAMMATORY PAIN INDUCED BY COMPLETE FREUND'S ADJUVANT (CFA). BACKGROUND: MULTIPLE MECHANISMS CONTRIBUTE TO THE STIMULUS-EVOKED PAIN HYPERSENSITIVITY THAT MAY BE EXPERIENCED AFTER PERIPHERAL INFLAMMATION. PERSISTENT PATHOLOGICAL STIMULI IN MANY PAIN CONDITIONS AFFECT THE EXPRESSION OF CERTAIN GENES THROUGH EPIGENETIC ALTERNATIONS. THE MAIN PURPOSE OF OUR STUDY WAS TO INVESTIGATE THE ROLE OF EPIGENETIC MODIFICATION ON POTASSIUM-CHLORIDE CO-TRANSPORTER 2 (KCC2) GENE EXPRESSION IN THE PERSISTENCE OF INFLAMMATORY PAIN. METHODS: PERSISTENT INFLAMMATORY PAIN WAS INDUCED THROUGH THE INJECTION OF COMPLETE FREUND'S ADJUVANT (CFA) IN THE LEFT HIND PAW OF RATS. ACETYL-HISTONE H3 AND H4 LEVEL WAS DETERMINED BY CHROMATIN IMMUNOPRECIPITATION IN THE SPINAL DORSAL HORN. PAIN BEHAVIOUR AND INHIBITORY SYNAPTIC FUNCTION OF SPINAL CORD WERE DETERMINED BEFORE AND AFTER CFA INJECTION. KCC2 EXPRESSION WAS DETERMINED BY REAL TIME RT-PCR AND WESTERN BLOT. INTRATHECAL KCC2 SIRNA (2 MUG PER 10 MUL PER RAT) OR HDAC INHIBITOR (10 MUG PER 10 MUL PER RAT) WAS INJECTED ONCE DAILY FOR 3 DAYS BEFORE CFA INJECTION. RESULTS: PERSISTENT INFLAMMATORY PAIN EPIGENETICALLY SUPPRESSED KCC2 EXPRESSION THROUGH HISTONE DEACETYLASE (HDAC)-MEDIATED HISTONE HYPOACETYLATION, RESULTING IN DECREASED INHIBITORY SIGNALLING EFFICACY. KCC2 KNOCK-DOWN CAUSED BY INTRATHECAL ADMINISTRATION OF KCC2 SIRNA IN NAIVE RATS REDUCED KCC2 EXPRESSION IN THE SPINAL CORD, LEADING TO SENSITIZED PAIN BEHAVIOURS AND IMPAIRED INHIBITORY SYNAPTIC TRANSMISSION IN THEIR SPINAL CORDS. MOREOVER, INTRATHECAL HDAC INHIBITOR INJECTION IN CFA RATS INCREASED KCC2 EXPRESSION, PARTIALLY RESTORING THE SPINAL INHIBITORY SYNAPTIC TRANSMISSION AND RELIEVING THE SENSITIZED PAIN BEHAVIOUR. CONCLUSION: THESE FINDINGS SUGGEST THAT THE TRANSCRIPTION OF SPINAL KCC2 IS REGULATED BY HISTONE ACETYLATION EPIGENETICALLY FOLLOWING CFA. SIGNIFICANCE: PERSISTENT PAIN SUPPRESSES KCC2 EXPRESSION THROUGH HDAC-MEDIATED HISTONE HYPOACETYLATION AND CONSEQUENTLY IMPAIRS THE INHIBITORY FUNCTION OF INHIBITORY INTERNEURONS. DRUGS SUCH AS HDAC INHIBITORS THAT SUPPRESS THE INFLUENCES OF PERSISTENT PAIN ON THE EXPRESSION OF KCC2 MAY SERVE AS A NOVEL ANALGESIC. 2017 9 3832 29 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 10 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 11 5865 32 SUPPRESSION OF HDAC2 IN SPINAL CORD ALLEVIATES MECHANICAL HYPERALGESIA AND RESTORES KCC2 EXPRESSION IN A RAT MODEL OF BONE CANCER PAIN. EPIGENETIC MODULATION PARTICIPATES IN THE MECHANISM OF MULTIPLE TYPES OF PATHOLOGICAL PAIN, SO TARGETING THE INVOLVED REGULATORS MAY BE A PROMISING STRATEGY FOR PAIN TREATMENT. OUR PREVIOUS RESEARCH IDENTIFIED THE ANALGESIC EFFECT OF THE HISTONE DEACETYLASE (HDAC) INHIBITOR TRICHOSTATIN A (TSA) ON MECHANICAL HYPERALGESIA IN A RAT MODEL OF BONE CANCER PAIN (BCP) VIA RESTORATION OF MU-OPIOID RECEPTOR (MOR) EXPRESSION. HOWEVER, THE SPECIFIC TYPES OF HDACS CONTRIBUTING TO BCP HAVE NOT BEEN EXPLORED. THE PRESENT STUDY INVESTIGATED THE EXPRESSION PATTERN OF SOME COMMON HDACS AND FOUND THAT HDAC2 WAS UP-REGULATED IN A TIME-DEPENDENT MANNER IN THE LUMBAR SPINAL CORD OF BCP RATS. TSA APPLICATION SUPPRESSED HDAC2 EXPRESSION IN CULTURED PC12 CELLS AND REVERSED THE AUGMENTED HDAC2 IN BCP RATS. AN RNA-INTERFERING STRATEGY CONFIRMED THE ESSENTIAL ROLE OF HDAC2 IN THE MODULATION OF MECHANICAL HYPERALGESIA FOLLOWING TUMOR CELL INOCULATION, AND WE FURTHER EXAMINED ITS POSSIBLE DOWNSTREAM TARGETS. NOTABLY, HDAC2 KNOCK-DOWN DID NOT RESTORE MOR EXPRESSION, BUT IT ROBUSTLY REVERSED THE DOWN-REGULATION OF POTASSIUM-CHLORIDE COTRANSPORTER 2 (KCC2). THE IMPAIRED KCC2 EXPRESSION IS A VITAL MECHANISM OF MANY TYPES OF PATHOLOGICAL PAIN. THEREFORE, OUR RESULTS DEMONSTRATED THAT HDAC2 IN SPINAL CORD CONTRIBUTED TO THE MECHANICAL HYPERALGESIA IN BCP RATS, AND THIS EFFECT MAY BE ASSOCIATED WITH KCC2 MODULATION. 2018 12 1826 40 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 13 4699 36 NFATC2-DEPENDENT EPIGENETIC UPREGULATION OF CXCL14 IS INVOLVED IN THE DEVELOPMENT OF NEUROPATHIC PAIN INDUCED BY PACLITAXEL. BACKGROUND: THE MAJOR DOSE-LIMITING TOXICITY OF PACLITAXEL, ONE OF THE MOST COMMONLY USED DRUGS TO TREAT SOLID TUMOR, IS PAINFUL NEUROPATHY. HOWEVER, THE MOLECULAR MECHANISMS UNDERLYING PACLITAXEL-INDUCED PAINFUL NEUROPATHY ARE LARGELY UNCLARIFIED. METHODS: PAW WITHDRAWAL THRESHOLD WAS MEASURED IN THE RATS FOLLOWING INTRAPERITONEAL INJECTION OF PACLITAXEL. THE QPCR, WESTERN BLOTTING, PROTEIN OR CHROMATIN IMMUNOPRECIPITATION, CHIP-SEQ IDENTIFICATION OF NFATC2 BINDING SITES, AND MICROARRAY ANALYSIS WERE PERFORMED TO EXPLORE THE MOLECULAR MECHANISM. RESULTS: WE FOUND THAT PACLITAXEL TREATMENT INCREASED THE NUCLEAR EXPRESSION OF NFATC2 IN THE SPINAL DORSAL HORN, AND KNOCKDOWN OF NFATC2 WITH NFATC2 SIRNA SIGNIFICANTLY ATTENUATED THE MECHANICAL ALLODYNIA INDUCED BY PACLITAXEL. FURTHER BINDING SITE ANALYSIS UTILIZING CHIP-SEQ ASSAY COMBINING WITH GENE EXPRESSION PROFILE REVEALED A SHIFT OF NFATC2 BINDING SITE CLOSER TO TTS OF TARGET GENES IN DORSAL HORN AFTER PACLITAXEL TREATMENT. WE FURTHER FOUND THAT NFATC2 OCCUPANCY MAY DIRECTLY UPREGULATE THE CHEMOKINE CXCL14 EXPRESSION IN DORSAL HORN, WHICH WAS MEDIATED BY ENHANCED INTERACTION BETWEEN NFATC2 AND P300 AND CONSEQUENTLY INCREASED ACETYLATION OF HISTONE H4 IN CXCL14 PROMOTER REGION. ALSO, KNOCKDOWN OF CXCL14 IN DORSAL HORN SIGNIFICANTLY ATTENUATED MECHANICAL ALLODYNIA INDUCED BY PACLITAXEL. CONCLUSION: THESE RESULTS SUGGESTED THAT ENHANCED INTERACTION BETWEEN P300 AND NFATC2 MEDIATED THE EPIGENETIC UPREGULATION OF CXCL14 IN THE SPINAL DORSAL HORN, WHICH CONTRIBUTED TO THE CHEMOTHERAPEUTIC PACLITAXEL-INDUCED CHRONIC PAIN. 2020 14 3437 35 HYPERGLYCEMIC MICROENVIRONMENT COMPROMISES THE HOMEOSTASIS OF COMMUNICATION BETWEEN THE BONE-BRAIN AXIS BY THE EPIGENETIC REPRESSION OF THE OSTEOCALCIN RECEPTOR, GPR158 IN THE HIPPOCAMPUS. DIABETES MELLITUS (DM) IS A CHRONIC METABOLIC DISEASE, MAINLY CHARACTERIZED BY INCREASED BLOOD GLUCOSE AND INSULIN DYSFUNCTION. IN RESPONSE TO THE PERSISTENT SYSTEMIC HYPERGLYCEMIC STATE, NUMEROUS METABOLIC AND PHYSIOLOGICAL COMPLICATIONS HAVE ALREADY BEEN WELL CHARACTERIZED. HOWEVER, ITS RELATIONSHIP TO BONE FRAGILITY, COGNITIVE DEFICITS AND INCREASED RISK OF DEMENTIA STILL NEEDS TO BE BETTER UNDERSTOOD. THE IMPACT OF CHRONIC HYPERGLYCEMIA ON BONE PHYSIOLOGY AND ARCHITECTURE WAS ASSESSED IN A MODEL OF CHRONIC HYPERGLYCEMIA INDUCED BY A SINGLE INTRAPERITONEAL ADMINISTRATION OF STREPTOZOTOCIN (STZ; 55 MG/KG) IN WISTAR RATS. IN ADDITION, THE BONE-TO-BRAIN COMMUNICATION WAS INVESTIGATED BY ANALYZING THE GENE EXPRESSION AND METHYLATION STATUS OF GENES THAT ENCODE THE MAIN OSTEOKINES RELEASED BY THE BONE [FGF23 (FIBROBLAST GROWTH FACTOR 23), BGLAP (BONE GAMMA-CARBOXYGLUTAMATE PROTEIN) AND LCN2 (LIPOCALIN 2) AND THEIR RECEPTORS IN BOTH, THE BONE AND THE BRAIN [FGFR1 (FIBROBLAST GROWTH FACTOR RECEPTOR 1), GPR6A (G-PROTEIN COUPLED RECEPTOR FAMILY C GROUP 6 MEMBER A), GPR158 (G PROTEIN-COUPLED RECEPTOR 158) AND SLC22A17 (SOLUTE CARRIER FAMILY 22 MEMBER 17)]. IT WAS OBSERVED THAT CHRONIC HYPERGLYCEMIA NEGATIVELY IMPACTED ON BONE BIOLOGY AND COMPROMISED THE BALANCE OF THE BONE-BRAIN ENDOCRINE AXIS. ULTRASTRUCTURAL DISORGANIZATION WAS ACCOMPANIED BY GLOBAL DNA HYPOMETHYLATION AND CHANGES IN GENE EXPRESSION OF DNA-MODIFYING ENZYMES THAT WERE ACCOMPANIED BY CHANGES IN THE METHYLATION STATUS OF THE OSTEOKINE PROMOTER REGION BGLAP AND LCN2 (LIPOCALIN 2) IN THE FEMUR. ADDITIONALLY, THE CHRONIC HYPERGLYCEMIC STATE WAS ACCOMPANIED BY MODULATION OF GENE EXPRESSION OF THE OSTEOKINES FGF23 (FIBROBLAST GROWTH FACTOR 23), BGLAP (BONE GAMMA-CARBOXYGLUTAMATE PROTEIN) AND LCN2 (LIPOCALIN 2) IN THE DIFFERENT BRAIN REGIONS. HOWEVER, TRANSCRIPTIONAL REGULATION MEDIATED BY DNA METHYLATION WAS OBSERVED ONLY FOR THE OSTEOKINE RECEPTORS, FGFR1(FIBROBLAST GROWTH FACTOR RECEPTOR 1) IN THE STRIATUM AND GPR158 (G PROTEIN-COUPLED RECEPTOR 158) IN THE HIPPOCAMPUS. THIS IS A PIONEER STUDY DEMONSTRATING THAT THE CHRONIC HYPERGLYCEMIC STATE COMPROMISES THE CROSSTALK BETWEEN BONE TISSUE AND THE BRAIN, MAINLY AFFECTING THE HIPPOCAMPUS, THROUGH TRANSCRIPTIONAL SILENCING OF THE BGLAP RECEPTOR BY HYPERMETHYLATION OF GPR158 GENE. 2023 15 3196 22 HDAC INHIBITORS RESTORE C-FIBRE SENSITIVITY IN EXPERIMENTAL NEUROPATHIC PAIN MODEL. BACKGROUND AND PURPOSE: HYPOESTHESIA IS A CLINICAL FEATURE OF NEUROPATHIC PAIN. THE FEATURE IS PARTLY EXPLAINED BY THE EVIDENCE OF EPIGENETIC REPRESSION OF NAV 1.8 SODIUM CHANNEL IN THE DORSAL ROOT GANGLION (DRG). EXPERIMENTAL APPROACH: WE INVESTIGATED THE POSSIBILITY OF TRICHOSTATIN A (TSA), VALPROIC ACID (VPA) AND SUBEROYLANILIDE HYDROXAMIC ACID (SAHA) TO REVERSE THE UNIQUE C-FIBRE SENSITIVITY OBSERVED FOLLOWING PARTIAL LIGATION OF SCIATIC NERVE IN MICE. KEY RESULTS: NERVE INJURY-INDUCED DOWN-REGULATION OF DRG NAV 1.8 SODIUM CHANNEL AND C-FIBRE-RELATED HYPOESTHESIA WERE REVERSED BY TSA, VPA AND SAHA TREATMENTS, WHICH INHIBIT HISTONE DEACETYLASE (HDAC), AND INCREASE HISTONE ACETYLATION AT THE REGULATORY SEQUENCE OF NAV 1.8. CONCLUSIONS AND IMPLICATIONS: TAKEN TOGETHER, THESE STUDIES PROVIDE THE EVIDENCE THAT HYPOESTHESIA AND UNDERLYING DOWN-REGULATION OF NAV 1.8, NEGATIVE SYMPTOMS OBSERVED IN NERVE INJURY-INDUCED NEUROPATHIC PAIN MODELS ARE REGULATED BY AN EPIGENETIC CHROMATIN REMODELLING THROUGH HDAC-RELATED MACHINERIES. 2013 16 3721 35 INHIBITION OF CLASS II HISTONE DEACETYLASES IN THE SPINAL CORD ATTENUATES INFLAMMATORY HYPERALGESIA. BACKGROUND: SEVERAL CLASSES OF HISTONE DEACETYLASES (HDACS) ARE EXPRESSED IN THE SPINAL CORD THAT IS A CRITICAL STRUCTURE OF THE NOCICEPTIVE PATHWAY. HDAC-REGULATED HISTONE ACETYLATION IS AN IMPORTANT COMPONENT OF CHROMATIN REMODELING LEADING TO EPIGENETIC REGULATION OF GENE TRANSCRIPTION. TO UNDERSTAND THE ROLE OF HISTONE ACETYLATION IN EPIGENETIC REGULATION OF PATHOLOGICAL PAIN, WE HAVE STUDIED THE IMPACT OF DIFFERENT CLASSES OF HDACS IN THE SPINAL CORD ON INFLAMMATORY HYPERALGESIA INDUCED BY COMPLETE FREUND'S ADJUVANT (CFA). RESULTS: WE INTRATHECALLY APPLIED INHIBITORS SPECIFIC TO DIFFERENT CLASSES OF HDACS AND EVALUATED THEIR IMPACT ON INFLAMMATORY HYPERALGESIA. PRE-INJECTED INHIBITORS TARGETING CLASS I AS WELL AS II (SAHA, TSA, LAQ824) OR IIA (VPA, 4-PB) HDACS SIGNIFICANTLY DELAYED THE THERMAL HYPERALGESIA INDUCED BY UNILATERAL CFA INJECTION IN THE HINDPAW. EXISTING HYPERALGESIA INDUCED BY CFA WAS ALSO ATTENUATED BY THE HDAC INHIBITORS (HDACIS). IN CONTRAST, THESE INHIBITORS DID NOT INTERFERE WITH THE THERMAL RESPONSE EITHER IN NAIVE ANIMALS, OR ON THE CONTRALATERAL SIDE OF INFLAMED ANIMALS. INTERESTINGLY, MS-275 THAT SPECIFICALLY INHIBITS CLASS I HDACS FAILED TO ALTER THE HYPERALGESIA ALTHOUGH IT INCREASED HISTONE 3 ACETYLATION IN THE SPINAL CORD AS SAHA DID. USING IMMUNOBLOT ANALYSIS, WE FURTHER FOUND THAT THE LEVELS OF CLASS IIA HDAC MEMBERS (HDAC4, 5, 7, 9) IN THE SPINAL DORSAL HORN WERE UPREGULATED FOLLOWING CFA INJECTION WHILE THOSE OF CLASS I HDAC MEMBERS (HDAC1, 2, 3) REMAINED STABLE OR WERE SLIGHTLY REDUCED. CONCLUSIONS: OUR DATA SUGGEST THAT ACTIVITY OF CLASS II HDACS IN THE SPINAL CORD IS CRITICAL TO THE INDUCTION AND MAINTENANCE OF INFLAMMATORY HYPERALGESIA INDUCED BY CFA, WHILE ACTIVITY OF CLASS I HDACS MAY BE UNNECESSARY. COMPARISON OF THE EFFECTS OF HDACIS SPECIFIC TO CLASS II AND IIA AS WELL AS THE EXPRESSION PATTERN OF DIFFERENT HDACS IN THE SPINAL CORD IN RESPONSE TO CFA SUGGESTS THAT THE MEMBERS OF CLASS IIA HDACS MAY BE POTENTIAL TARGETS FOR ATTENUATING PERSISTENT INFLAMMATORY PAIN. 2010 17 2272 34 EPIGENETIC REDUCTION OF MIR-214-3P UPREGULATES ASTROCYTIC COLONY-STIMULATING FACTOR-1 AND CONTRIBUTES TO NEUROPATHIC PAIN INDUCED BY NERVE INJURY. EMERGING EVIDENCE HAS INDICATED THAT COLONY-STIMULATING FACTOR-1 (CSF1) MODULATES NEUROINFLAMMATION IN THE CENTRAL NERVOUS SYSTEM AND THE DEVELOPMENT OF NEUROPATHIC PAIN, WHILE THE UNDERLYING MECHANISM REMAINS UNKNOWN. HERE, WE IDENTIFIED THE INCREASED EXPRESSION OF CSF1 DERIVED FROM ACTIVATED ASTROCYTES IN THE IPSILATERAL DORSAL HORN IN RATS WITH SPINAL NERVE LIGATION (SNL). SUPPRESSION OF CSF1 EXPRESSION ALLEVIATED NEUROINFLAMMATION, NEURONAL HYPEREXCITABILITY, AND GLUTAMATERGIC RECEPTOR SUBUNIT UPREGULATION IN THE DORSAL HORN AND IMPROVED SNL-INDUCED PAIN BEHAVIOR. WE ALSO FOUND REDUCED MIR-214-3P EXPRESSION IN THE IPSILATERAL DORSAL HORN FOLLOWING AN SNL PROCEDURE; MIR-214-3P DIRECTLY BOUND TO THE 3'-UTR OF CSF1 MRNA AND NEGATIVELY REGULATED CSF1 EXPRESSION. INTRATHECAL DELIVERY OF MIR-214-3P MIMIC REVERSED THE ENHANCED EXPRESSION OF CSF1 AND ASTROCYTE OVERACTIVITY AND ALLEVIATED THE IL-6 UPREGULATION AND PAIN BEHAVIOR INDUCED BY SNL. MOREOVER, SUPPRESSION OF SPINAL MIR-214-3P INCREASED ASTROCYTE REACTIVITY, PROMOTED CSF1 AND IL-6 PRODUCTION, AND INDUCED PAIN HYPERSENSITIVITY IN NAIVE ANIMALS. FURTHERMORE, SNL INDUCED THE EXPRESSION OF DNA METHYLTRANSFERASE 3A (DNMT3A) THAT WAS ASSOCIATED WITH THE HYPERMETHYLATION OF THE MIR-214-3P PROMOTER, LEADING TO REDUCED MIR-214-3P EXPRESSION IN THE MODEL RODENTS. TREATMENT WITH THE DNMT INHIBITOR ZEBULARINE SIGNIFICANTLY REDUCED CYTOSINE METHYLATION IN THE MIR-214-3P PROMOTER; THIS REDUCED METHYLATION CONSEQUENTLY INCREASED THE EXPRESSION OF MIR-214-3P AND DECREASED THE CONTENT OF CSF1 IN THE IPSILATERAL DORSAL HORN AND, FURTHER, ATTENUATED IL-6 PRODUCTION AND PAIN BEHAVIOR IN RATS WITH SNL. TOGETHER, OUR DATA INDICATE THAT THE DNMT3A-MEDIATED EPIGENETIC SUPPRESSION OF MIR-214-3P ENHANCED CSF1 PRODUCTION IN ASTROCYTES, WHICH SUBSEQUENTLY INDUCED NEUROINFLAMMATION AND PAIN BEHAVIOR IN SNL MODEL RATS. 2020 18 1654 32 DORSAL ROOT GANGLIA COACTIVATOR-ASSOCIATED ARGININE METHYLTRANSFERASE 1 CONTRIBUTES TO PERIPHERAL NERVE INJURY-INDUCED PAIN HYPERSENSITIVITIES. NEUROPATHIC PAIN IS ASSOCIATED WITH GENE EXPRESSION CHANGES WITHIN THE DORSAL ROOT GANGLION (DRG) AFTER PERIPHERAL NERVE INJURY, WHICH INVOLVES EPIGENETIC MECHANISMS. COACTIVATOR-ASSOCIATED ARGININE METHYLTRANSFERASE 1 (CARM1), AN EPIGENETIC ACTIVATOR, REGULATES GENE TRANSCRIPTIONAL ACTIVITY BY PROTEIN POSTTRANSLATIONAL MODIFICATIONS. HOWEVER, WHETHER CARM1 PLAYS AN ESSENTIAL ROLE IN THE DEVELOPMENT AND MAINTENANCE OF NEUROPATHIC PAIN IS UNKNOWN. WE REPORT HERE THAT PERIPHERAL NERVE INJURY INDUCED THE UPREGULATION OF THE MRNA AND PROTEIN EXPRESSION OF CARM1 IN THE INJURED DRG, AND BLOCKING ITS EXPRESSION THROUGH SMALL INTERFERING RNA (SIRNA) IN THE INJURED DRG ATTENUATED THE DEVELOPMENT AND MAINTENANCE OF NEUROPATHIC PAIN. FURTHERMORE, PHARMACOLOGICAL INHIBITION OF CARM1 MITIGATED PERIPHERAL NERVE INJURY-INDUCED MECHANICAL ALLODYNIA AND THERMAL HYPERALGESIA. GIVEN THAT CARM1 INHIBITION OR KNOCKDOWN ATTENUATED THE INDUCTION AND MAINTENANCE OF NEUROPATHIC PAIN AFTER PERIPHERAL NERVE INJURY, OUR FINDINGS SUGGEST THAT CARM1 MAY SERVE AS A PROMISING THERAPEUTIC TARGET FOR NEUROPATHIC PAIN TREATMENT IN CLINICAL APPLICATIONS. 2018 19 5574 31 ROLE OF MICRORNA-143 IN NERVE INJURY-INDUCED UPREGULATION OF DNMT3A EXPRESSION IN PRIMARY SENSORY NEURONS. PERIPHERAL NERVE INJURY INCREASED THE EXPRESSION OF THE DNA METHYLTRANSFERASE 3A (DNMT3A) MRNA AND ITS ENCODING DNMT3A PROTEIN IN INJURED DORSAL ROOT GANGLIA (DRG). THIS INCREASE IS CONSIDERED AS AN ENDOGENOUS INSTIGATOR IN NEUROPATHIC PAIN GENESIS THROUGH EPIGENETIC SILENCING OF PAIN-ASSOCIATED GENES (SUCH AS OPRM1) IN INJURED DRG. HOWEVER, HOW DRG DNMT3A IS INCREASED FOLLOWING PERIPHERAL NERVE INJURY IS STILL ELUSIVE. WE REPORTED HERE THAT PERIPHERAL NERVE INJURY CAUSED BY THE FIFTH SPINAL NERVE LIGATION (SNL) DOWNREGULATED MICRORNA (MIR)-143 EXPRESSION IN INJURED DRG. THIS DOWNREGULATION WAS REQUIRED FOR SNL-INDUCED DRG DNMT3A INCREASE AS RESCUING MIR-143 DOWNREGULATION THROUGH MICROINJECTION OF MIR-143 MIMICS INTO INJURED DRG BLOCKED THE SNL-INDUCED INCREASE IN DNMT3A AND RESTORED THE SNL-INDUCED DECREASES IN OPRM1 MRNA AND ITS ENCODING MU OPIOID RECEPTOR (MOR) IN INJURED DRG, IMPAIRED SPINAL CORD CENTRAL SENSITIZATION AND NEUROPATHIC PAIN, AND IMPROVED MORPHINE ANALGESIC EFFECTS FOLLOWING SNL. MIMICKING SNL-INDUCED DRG MIR-143 DOWNREGULATION THROUGH DRG MICROINJECTION OF MIR143 INHIBITORS IN NAIVE RATS INCREASED THE EXPRESSION OF DNMT3A AND REDUCED THE EXPRESSION OF OPRM1 MRNA AND MOR IN INJECTED DRG AND PRODUCED NEUROPATHIC PAIN-LIKE SYMPTOMS. THESE FINDINGS SUGGEST THAT MIR-143 IS A NEGATIVE REGULATOR IN DNMT3A EXPRESSION IN THE DRG UNDER NEUROPATHIC PAIN CONDITIONS AND MAY BE A POTENTIAL TARGET FOR THERAPEUTIC MANAGEMENT OF NEUROPATHIC PAIN. 2017 20 2300 32 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