1 2969 513 GENETIC AND EPIGENETIC REGULATION OF THE INNATE IMMUNE RESPONSE TO GOUT. GOUT IS A DISEASE CAUSED BY URIC ACID (UA) ACCUMULATION IN THE JOINTS, CAUSING INFLAMMATION. TWO UA FORMS - MONOSODIUM URATE (MSU) AND SOLUBLE URIC ACID (SUA) HAVE BEEN SHOWN TO INTERACT PHYSICALLY WITH INFLAMMASOMES, ESPECIALLY WITH THE NOD-LIKE RECEPTOR (NLR) FAMILY PYRIN DOMAIN CONTAINING 3 (NLRP3), ALBEIT THE ROLE OF THE IMMUNE RESPONSE TO UA IS POORLY UNDERSTOOD, GIVEN THAT ASYMPTOMATIC HYPERURICEMIA DOES ALSO EXIST. MACROPHAGE PHAGOCYTOSIS OF UA ACTIVATE NLRP3, LEAD TO CYTOKINES RELEASE, AND ULTIMATELY, LEAD TO CHEMOATTRACT NEUTROPHILS AND LYMPHOCYTES TO THE GOUT FLARE JOINT SPOT. GENETIC VARIANTS OF INFLAMMASOME GENES AND OF GENES ENCODING THEIR MOLECULAR PARTNERS MAY INFLUENCE HYPERURICEMIA AND GOUT SUSCEPTIBILITY, WHILE ALSO INFLUENCING OTHER COMORBIDITIES SUCH AS METABOLIC SYNDROME AND CARDIOVASCULAR DISEASES. IN THIS REVIEW, WE SUMMARIZE THE INFLAMMATORY RESPONSES IN ACUTE AND CHRONIC GOUT, SPECIFICALLY FOCUSING ON INNATE IMMUNE CELL MECHANISMS AND GENETIC AND EPIGENETIC CHARACTERISTICS OF PARTICIPATING MOLECULES. UNPRECEDENTLY, A NOVEL UA BINDING PROTEIN - THE NEURONAL APOPTOSIS INHIBITOR PROTEIN (NAIP) - IS SUGGESTED AS RESPONSIBLE FOR THE ASYMPTOMATIC HYPERURICEMIA PARADOX.ABBREVIATION: BETA2-INTEGRINS: LEUKOCYTE-SPECIFIC ADHESION MOLECULES; ABCG2: ATP-BINDING CASSETE FAMILY/BREAST CANCER-RESISTANT PROTEIN; ACR: AMERICAN COLLEGE OF RHEUMATOLOGY; AIM2: ABSENT IN MELANOMA 2, TYPE OF PATTERN RECOGNITION RECEPTOR; ALPK1: ALPHA-PROTEIN KINASE 1; ANGPTL2: ANGIOPOIETIN-LIKE PROTEIN 2; ASC: APOPTOSIS-ASSOCIATED SPECK-LIKE PROTEIN; BIR: BACULOVIRUS INHIBITOR OF APOPTOSIS PROTEIN REPEAT; BIRC1: BACULOVIRUS IAP REPEAT-CONTAINING PROTEIN 1; BIRC2: BACULOVIRAL IAP REPEAT-CONTAINING PROTEIN 2; C5A: COMPLEMENT ANAPHYLATOXIN; CAMP: CYCLIC ADENOSINE MONOPHOSPHATE; CARD: CASPASE ACTIVATION AND RECRUITMENT DOMAINS; CARD8: CASPASE RECRUITMENT DOMAIN-CONTAINING PROTEIN 8; CASP1: CASPASE 1; CCL3: CHEMOKINE (C-C MOTIF) LIGAND 3; CD14: CLUSTER OF DIFFERENTIATION 14; CD44: CLUSTER OF DIFFERENTIATION 44; CG05102552: DNA-METHYLATION SITE, USUALLY CYTOSINE FOLLOWED BY GUANINE NUCLEOTIDES; CONTAINS ARBITRARY IDENTIFICATION CODE; CIDEC: CELL DEATH-INDUCING DNA FRAGMENTATION FACTOR-LIKE EFFECTOR FAMILY; CKD: CHRONIC KIDNEY DISEASE; CNV: COPY NUMBER VARIATION; CPT1A: CARNITINE PALMITOYL TRANSFERASE - TYPE 1A; CXCL1: CHEMOKINE (CXC MOTIF) LIGAND 1; DAMPS: DAMAGE ASSOCIATED MOLECULAR PATTERNS; DC: DENDRITIC CELLS; DNMT(1): MAINTENANCE DNA METHYLTRANSFERASE; EQTL: EXPRESSION QUANTITATIVE TRAIT LOCI; ERK1: EXTRACELLULAR SIGNAL-REGULATED KINASE 1; ERK2: EXTRACELLULAR SIGNAL-REGULATED KINASE 2; EULAR: EUROPEAN LEAGUE AGAINST RHEUMATISM; GMCSF: GRANULOCYTE-MACROPHAGE COLONY-STIMULATING FACTOR; GWAS: GLOBAL WIDE ASSOCIATION STUDIES; H3K27ME3: TRI-METHYLATION AT THE 27TH LYSINE RESIDUE OF THE HISTONE H3 PROTEIN; H3K4ME1: MONO-METHYLATION AT THE 4TH LYSINE RESIDUE OF THE HISTONE H3 PROTEIN; H3K4ME3: TRI-METHYLATION AT THE 4TH LYSINE RESIDUE OF THE HISTONE H3 PROTEIN; HOTAIR: HUMAN GENE LOCATED BETWEEN HOXC11 AND HOXC12 ON CHROMOSOME 12; IKAPPABALPHA: CYTOPLASMATIC PROTEIN/NF-KAPPAB TRANSCRIPTION INHIBITOR; IAP: INHIBITORY APOPTOSIS PROTEIN; IFNGAMMA: INTERFERON GAMMA; IL-1BETA: INTERLEUKIN 1 BETA; IL-12: INTERLEUKIN 12; IL-17: INTERLEUKIN 17; IL18: INTERLEUKIN 18; IL1R1: INTERLEUKIN-1 RECEPTOR; IL-1RA: INTERLEUKIN-1 RECEPTOR ANTAGONIST; IL-22: INTERLEUKIN 22; IL-23: INTERLEUKIN 23; IL23R: INTERLEUKIN 23 RECEPTOR; IL-33: INTERLEUKIN 33; IL-6: INTERLEUKIN 6; IMP: INOSINE MONOPHOSPHATE; INSIG1: INSULIN-INDUCED GENE 1; JNK1: C-JUN N-TERMINAL KINASE 1; LNCRNA: LONG NON-CODING RIBONUCLEIC ACID; LRR: LEUCINE-RICH REPEATS; MIR: MATURE NON-CODING MICRORNAS MEASURING FROM 20 TO 24 NUCLEOTIDES, ANIMAL ORIGIN; MIR-1: MIR FOLLOWED BY ARBITRARY IDENTIFICATION CODE; MIR-145: MIR FOLLOWED BY ARBITRARY IDENTIFICATION CODE; MIR-146A: MIR FOLLOWED BY ARBITRARY IDENTIFICATION CODE, "A" STANDS FOR MIR FAMILY; "A" FAMILY PRESENTS SIMILAR MIR SEQUENCE TO "B" FAMILY, BUT DIFFERENT PRECURSORS; MIR-20B: MIR FOLLOWED BY ARBITRARY IDENTIFICATION CODE; "B" STANDS FOR MIR FAMILY; "B" FAMILY PRESENTS SIMILAR MIR SEQUENCE TO "A" FAMILY, BUT DIFFERENT PRECURSORS; MIR-221: MIR - FOLLOWED BY ARBITRARY IDENTIFICATION CODE; MIR-221-5P: MIR FOLLOWED BY ARBITRARY IDENTIFICATION CODE; "5P" INDICATES DIFFERENT MATURE MIRNAS GENERATED FROM THE 5' ARM OF THE PRE-MIRNA HAIRPIN; MIR-223: MIR FOLLOWED BY ARBITRARY IDENTIFICATION CODE; MIR-223-3P: MIR FOLLOWED BY ARBITRARY IDENTIFICATION CODE; "3P" INDICATES DIFFERENT MATURE MIRNAS GENERATED FROM THE 3' ARM OF THE PRE-MIRNA HAIRPIN; MIR-22-3P: MIR FOLLOWED BY ARBITRARY IDENTIFICATION CODE, "3P" INDICATES DIFFERENT MATURE MIRNAS GENERATED FROM THE 3' ARM OF THE PRE-MIRNA HAIRPIN; MLKL: MIXED LINEAGE KINASE DOMAIN-LIKE PSEUDO KINASE; MM2P: INDUCTOR OF M2-MACROPHAGE POLARIZATION; MSU: MONOSODIUM URATE; MTOR: MAMMALIAN TARGET OF RAPAMYCIN; MYD88: MYELOID DIFFERENTIATION PRIMARY RESPONSE 88; N-3-PUFAS: N-3-POLYUNSATURATED FATTY-ACIDS; NACHT: ACRONYM FOR NAIP (NEURONAL APOPTOSIS INHIBITOR PROTEIN), C2TA (MHC CLASS 2 TRANSCRIPTION ACTIVATOR), HET-E (INCOMPATIBILITY LOCUS PROTEIN FROM PODOSPORA ANSERINA) AND TP1 (TELOMERASE-ASSOCIATED PROTEIN); NAIP: NEURONAL APOPTOSIS INHIBITORY PROTEIN (HUMAN); NAIP1: NEURONAL APOPTOSIS INHIBITORY PROTEIN TYPE 1 (MURINE); NAIP5: NEURONAL APOPTOSIS INHIBITORY PROTEIN TYPE 5 (MURINE); NAIP6: NEURONAL APOPTOSIS INHIBITORY PROTEIN TYPE 6 (MURINE); NBD: NUCLEOTIDE-BINDING DOMAIN; NEK7: SMALLEST NIMA-RELATED KINASE; NET: NEUTROPHIL EXTRACELLULAR TRAPS; NF-KAPPAB: NUCLEAR FACTOR KAPPA-LIGHT-CHAIN-ENHANCER OF ACTIVATED B CELLS; NFIL3: NUCLEAR-FACTOR, INTERLEUKIN 3 REGULATED PROTEIN; NIIMA: NETWORK OF IMMUNITY IN INFECTION, MALIGNANCY, AND AUTOIMMUNITY; NLR: NOD-LIKE RECEPTOR; NLRA: NOD-LIKE RECEPTOR NLRA CONTAINING ACIDIC DOMAIN; NLRB: NOD-LIKE RECEPTOR NLRA CONTAINING BIR DOMAIN; NLRC: NOD-LIKE RECEPTOR NLRA CONTAINING CARD DOMAIN; NLRC4: NOD-LIKE RECEPTOR FAMILY CARD DOMAIN CONTAINING 4; NLRP: NOD-LIKE RECEPTOR NLRA CONTAINING PYD DOMAIN; NLRP1: NUCLEOTIDE-BINDING OLIGOMERIZATION DOMAIN, LEUCINE-RICH REPEAT, AND PYRIN DOMAIN CONTAINING 1; NLRP12: NUCLEOTIDE-BINDING OLIGOMERIZATION DOMAIN, LEUCINE-RICH REPEAT, AND PYRIN DOMAIN CONTAINING 12; NLRP3: NOD-LIKE RECEPTOR FAMILY PYRIN DOMAIN CONTAINING 3; NOD2: NUCLEOTIDE-BINDING OLIGOMERIZATION DOMAIN; NRBP1: NUCLEAR RECEPTOR-BINDING PROTEIN; NRF2: NUCLEAR FACTOR ERYTHROID 2-RELATED FACTOR 2; OR: ODDS RATIO; P2X: GROUP OF MEMBRANE ION CHANNELS ACTIVATED BY THE BINDING OF EXTRACELLULAR; P2X7: P2X PURINOCEPTOR 7 GENE; P38: MEMBER OF THE MITOGEN-ACTIVATED PROTEIN KINASE FAMILY; PAMPS: PATHOGEN ASSOCIATED MOLECULAR PATTERS; PBMC: PERIPHERAL BLOOD MONONUCLEAR CELLS; PGGT1B: GERANYLGERANYL TRANSFERASE TYPE-1 SUBUNIT BETA; PHGDH: PHOSPHOGLYCERATE DEHYDROGENASE; PI3-K: PHOSPHO-INOSITOL; PPARGAMMA: PEROXISOME PROLIFERATOR-ACTIVATED RECEPTOR GAMMA; PPARGC1B: PEROXISOME PROLIFERATIVE ACTIVATED RECEPTOR, GAMMA, COACTIVATOR 1 BETA; PR3: PROTEINASE 3 ANTIGEN; PRO-CASP1: INACTIVE PRECURSOR OF CASPASE 1; PRO-IL1BETA: INACTIVE PRECURSOR OF INTERLEUKIN 1 BETA; PRR: PATTERN RECOGNITION RECEPTORS; PYD: PYRIN DOMAIN; RAPTOR: REGULATORY ASSOCIATED PROTEIN OF MTOR COMPLEX 1; RAS: RENIN-ANGIOTENSIN SYSTEM; REDD1: REGULATED IN DNA DAMAGE AND DEVELOPMENT 1; ROS: REACTIVE OXYGEN SPECIES; RS000*G: SINGLE NUCLEAR POLYMORPHISM, "*G" IS RELATED TO SNP WHERE REPLACED NUCLEOTIDE IS GUANINE, USUALLY PRECEDED BY AN ID NUMBER; SLC2A9: SOLUTE CARRIER FAMILY 2, MEMBER 9; SLC7A11: SOLUTE CARRIER FAMILY 7, MEMBER 11; SMA: SMOOTH MUSCULAR ATROPHY; SMAC: SECOND MITOCHONDRIAL-DERIVED ACTIVATOR OF CASPASES; SNP: SINGLE NUCLEAR POLYMORPHISM; SP3: SPECIFICITY PROTEIN 3; ST2: SERUM STIMULATION-2; STK11: SERINE/THREONINE KINASE 11; SUA: SOLUBLE URIC ACID; SYK: SPLEEN TYROSINE KINASE; TAK1: TRANSFORMING GROWTH FACTOR BETA ACTIVATED KINASE; TH1: TYPE 1 HELPER T CELLS; TH17: TYPE 17 HELPER T CELLS; TH2: TYPE 2 HELPER T CELLS; TH22: TYPE 22 HELPER T CELLS; TLR: TOOL-LIKE RECEPTOR; TLR2: TOLL-LIKE RECEPTOR 2; TLR4: TOLL-LIKE RECEPTOR 4; TNFALPHA: TUMOR NECROSIS FACTOR ALPHA; TNFR1: TUMOR NECROSIS FACTOR RECEPTOR 1; TNFR2: TUMOR NECROSIS FACTOR RECEPTOR 2; UA: URIC ACID; UBAP1: UBIQUITIN ASSOCIATED PROTEIN; ULT: URATE-LOWERING THERAPY; URAT1: URATE TRANSPORTER 1; VDAC1: VOLTAGE-DEPENDENT ANION-SELECTIVE CHANNEL 1. 2023 2 6669 46 URIC ACID IN METABOLIC SYNDROME: DOES URIC ACID HAVE A DEFINITIVE ROLE? INCREASED SERUM URIC ACID (SUA) LEVELS ARE COMMONLY SEEN IN PATIENTS WITH METABOLIC SYNDROME AND ARE WIDELY ACCEPTED AS RISK FACTORS FOR HYPERTENSION, GOUT, NON-ALCOHOLIC FATTY LIVER DISEASE, CHRONIC KIDNEY DISEASE (CKD), AND CARDIOVASCULAR DISEASES. ALTHOUGH SOME AMBIGUITY FOR THE EXACT ROLE OF URIC ACID (UA) IN THESE DISEASES IS STILL PRESENT, SEVERAL PATHOPHYSIOLOGICAL MECHANISMS HAVE BEEN IDENTIFIED SUCH AS INCREASED OXIDATIVE STRESS, INFLAMMATION, AND APOPTOSIS. ACCUMULATING EVIDENCE IN GENOMICS ENLIGHTENS GENETIC VARIABILITIES AND SOME EPIGENETIC CHANGES THAT CAN CONTRIBUTE TO HYPERURICEMIA. HERE WE DISCUSS THE ROLE OF UA WITHIN METABOLISM AND THE CONSEQUENCES OF ASYMPTOMATIC HYPERURICEMIA WHILE PROVIDING NEWFOUND EVIDENCE FOR THE ASSOCIATIONS BETWEEN UA AND GUT MICROBIOTA AND VITAMIN D. INCREASED SUA LEVELS AND BENEFICIAL EFFECTS OF LOWERING SUA LEVELS NEED TO BE ELUCIDATED MORE TO UNDERSTAND ITS COMPLICATED FUNCTION WITHIN DIFFERENT METABOLIC PATHWAYS AND SET OPTIMAL TARGET LEVELS FOR SUA FOR REDUCING RISKS FOR METABOLIC AND CARDIOVASCULAR DISEASES. 2022 3 5760 58 SOLUBLE URIC ACID PRIMES TLR-INDUCED PROINFLAMMATORY CYTOKINE PRODUCTION BY HUMAN PRIMARY CELLS VIA INHIBITION OF IL-1RA. OBJECTIVES: THE STUDY OF THE PROINFLAMMATORY ROLE OF URIC ACID HAS FOCUSED ON THE EFFECTS OF ITS CRYSTALS OF MONOSODIUM URATE (MSU). HOWEVER, LITTLE IS KNOWN WHETHER URIC ACID ITSELF CAN DIRECTLY HAVE PROINFLAMMATORY EFFECTS. IN THIS STUDY, WE INVESTIGATE THE PRIMING EFFECTS OF URIC ACID EXPOSURE ON THE CYTOKINE PRODUCTION OF PRIMARY HUMAN CELLS UPON STIMULATION WITH GOUT-RELATED STIMULI. METHODS: PERIPHERAL BLOOD MONONUCLEAR CELLS (PBMCS) WERE HARVESTED FROM PATIENTS WITH GOUT AND HEALTHY VOLUNTEERS. CELLS WERE PRETREATED WITH OR WITHOUT URIC ACID IN SOLUBLE FORM FOR 24 H AND THEN STIMULATED FOR 24 H WITH TOLL-LIKE RECEPTOR (TLR)2 OR TLR4 LIGANDS IN THE PRESENCE OR ABSENCE OF MSU CRYSTALS. CYTOKINE PRODUCTION WAS MEASURED BY ELISA; MRNA LEVELS WERE ASSESSED USING QPCR. RESULTS: THE PRODUCTION OF INTERLEUKIN (IL)-1BETA AND IL-6 WAS HIGHER IN PATIENTS COMPARED WITH CONTROLS AND THIS CORRELATED WITH SERUM URATE LEVELS. PROINFLAMMATORY CYTOKINE PRODUCTION WAS SIGNIFICANTLY POTENTIATED WHEN CELLS FROM HEALTHY SUBJECTS WERE PRETREATED WITH URIC ACID. SURPRISINGLY, THIS WAS ASSOCIATED WITH A SIGNIFICANT DOWNREGULATION OF THE ANTI-INFLAMMATORY CYTOKINE IL-1 RECEPTOR ANTAGONIST (IL-1RA). THIS EFFECT WAS SPECIFIC TO STIMULATION BY URIC ACID AND WAS EXERTED AT THE LEVEL OF GENE TRANSCRIPTION. EPIGENETIC REPROGRAMMING AT THE LEVEL OF HISTONE METHYLATION BY URIC ACID WAS INVOLVED IN THIS EFFECT. CONCLUSIONS: IN THIS STUDY WE DEMONSTRATE A MECHANISM THROUGH WHICH HIGH CONCENTRATIONS OF URIC ACID (UP TO 50 MG/DL) INFLUENCE INFLAMMATORY RESPONSES BY FACILITATING IL-1BETA PRODUCTION IN PBMCS. WE SHOW THAT A MECHANISM FOR THE AMPLIFICATION OF IL-1BETA CONSISTS IN THE DOWNREGULATION OF IL-1RA AND THAT THIS EFFECT COULD BE EXERTED VIA EPIGENETIC MECHANISMS SUCH AS HISTONE METHYLATION. HYPERURICAEMIA CAUSES A SHIFT IN THE IL-1BETA/IL-1RA BALANCE PRODUCED BY PBMCS AFTER EXPOSURE TO MSU CRYSTALS AND TLR-MEDIATED STIMULI, AND THIS PHENOMENON IS LIKELY TO REINFORCE THE ENHANCED STATE OF CHRONIC INFLAMMATION. 2016 4 3701 55 INFLAMMATORY RESPONSE TO REGULATED CELL DEATH IN GOUT AND ITS FUNCTIONAL IMPLICATIONS. GOUT, A CHRONIC INFLAMMATORY ARTHRITIS DISEASE, IS CHARACTERIZED BY HYPERURICEMIA AND CAUSED BY INTERACTIONS BETWEEN GENETIC, EPIGENETIC, AND METABOLIC FACTORS. ACUTE GOUT SYMPTOMS ARE TRIGGERED BY THE INFLAMMATORY RESPONSE TO MONOSODIUM URATE CRYSTALS, WHICH IS MEDIATED BY THE INNATE IMMUNE SYSTEM AND IMMUNE CELLS (E.G., MACROPHAGES AND NEUTROPHILS), THE NACHT, LRR, AND PYD DOMAINS-CONTAINING PROTEIN 3 (NLRP3) INFLAMMASOME ACTIVATION, AND PRO-INFLAMMATORY CYTOKINE (E.G., IL-1BETA) RELEASE. RECENT STUDIES HAVE INDICATED THAT THE MULTIPLE PROGRAMMED CELL DEATH PATHWAYS INVOLVED IN THE INFLAMMATORY RESPONSE INCLUDE PYROPTOSIS, NETOSIS, NECROPTOSIS, AND APOPTOSIS, WHICH INITIATE INFLAMMATORY REACTIONS. IN THIS REVIEW, WE EXPLORE THE CORRELATION AND INTERACTIONS AMONG THESE FACTORS AND THEIR ROLES IN THE PATHOGENESIS OF GOUT TO PROVIDE FUTURE RESEARCH DIRECTIONS AND POSSIBILITIES FOR IDENTIFYING POTENTIAL NOVEL THERAPEUTIC TARGETS AND ENHANCING OUR UNDERSTANDING OF GOUT PATHOGENESIS. 2022 5 5594 48 ROLES OF AIM2 GENE AND AIM2 INFLAMMASOME IN THE PATHOGENESIS AND TREATMENT OF PSORIASIS. PSORIASIS IS AN IMMUNE-MEDIATED CHRONIC INFLAMMATORY SKIN DISEASE CAUSED BY A COMBINATION OF ENVIRONMENTAL INCENTIVES, POLYGENIC GENETIC CONTROL, AND IMMUNE REGULATION. THE INFLAMMATION-RELATED GENE ABSENT IN MELANOMA 2 (AIM2) WAS IDENTIFIED AS A SUSCEPTIBILITY GENE FOR PSORIASIS. AIM2 INFLAMMASOME FORMED FROM THE COMBINATION OF AIM2, PYD-LINKED APOPTOSIS-ASSOCIATED SPECK-LIKE PROTEIN (ASC) AND CASPASE-1 PROMOTES THE MATURATION AND RELEASE OF INFLAMMATORY CYTOKINES SUCH AS IL-1BETA AND IL-18, AND TRIGGERS AN INFLAMMATORY RESPONSE. STUDIES SHOWED THE GENETIC AND EPIGENETIC ASSOCIATIONS BETWEEN AIM2 GENE AND PSORIASIS. AIM2 GENE HAS AN ESSENTIAL ROLE IN THE OCCURRENCE AND DEVELOPMENT OF PSORIASIS, AND THE INHIBITORS OF AIM2 INFLAMMASOME WILL BE NEW THERAPEUTIC TARGETS FOR PSORIASIS. IN THIS REVIEW, WE SUMMARIZED THE ROLES OF THE AIM2 GENE AND AIM2 INFLAMMASOME IN PATHOGENESIS AND TREATMENT OF PSORIASIS, HOPEFULLY PROVIDING A BETTER UNDERSTANDING AND NEW INSIGHT INTO THE ROLES OF AIM2 GENE AND AIM2 INFLAMMASOME IN PSORIASIS. 2022 6 537 38 ASYMPTOMATIC HYPERURICEMIA: IS IT REALLY ASYMPTOMATIC? PURPOSE OF REVIEW: HYPERURICEMIA IS HIGHLY PREVALENT, AFFECTING APPROXIMATELY 38 MILLION INDIVIDUALS IN THE UNITED STATES. HOWEVER, THE SIGNIFICANCE OF ASYMPTOMATIC HYPERURICEMIA - HYPERURICEMIA IN THE ABSENCE OF GOUT - CONTINUES TO BE DEBATED. RECENT FINDINGS: ASYMPTOMATIC HYPERURICEMIA RESULTS IN MONOSODIUM URATE CRYSTAL DEPOSITION IN TISSUES, WHICH MAY PROMOTE CHRONIC INFLAMMATION. INTRACELLULARLY, HYPERURICEMIA INHIBITS THE MASTER REGULATOR ADENOSINE MONOPHOSPHATE (AMP)-ASSOCIATED PROTEIN KINASE AND MAY CONDITION INNATE IMMUNE RESPONSES THROUGH DURABLE EPIGENETIC MODIFICATIONS. AT THE POPULATION LEVEL, ASYMPTOMATIC HYPERURICEMIA IS ASSOCIATED WITH MULTIPLE COMORBIDITIES, INCLUDING HYPERTENSION, CHRONIC KIDNEY DISEASE, CORONARY ARTERY DISEASE, AND DIABETES; LIMITATIONS OF THESE STUDIES INCLUDE THAT MOST ARE RETROSPECTIVE AND SOME DO NOT RIGOROUSLY DISTINGUISH BETWEEN ASYMPTOMATIC HYPERURICEMIA AND GOUT. TREATMENT STUDIES SUGGEST THAT URATE LOWERING MAY REDUCE THE RISK OF INCIDENCE OR PROGRESSION OF SOME OF THESE COMORBIDITIES; UNFORTUNATELY, MANY OF THESE TREATMENT STUDIES ARE SMALL OR FLAWED, AND NOT ALL STUDY RESULTS ARE CONSISTENT. SUMMARY: ACCUMULATING EVIDENCE SUGGESTS THAT ASYMPTOMATIC HYPERURICEMIA CONTRIBUTES TO THE COMORBIDITIES WITH WHICH IT ASSOCIATES AND THAT PROPER ASYMPTOMATIC HYPERURICEMIA TREATMENT MAY REDUCE FUTURE RISK. ADDITIONAL PROSPECTIVE TRIALS ARE NEEDED TO DEFINITELY ESTABLISH CAUSALITY AND SUPPORT DECISION-MAKING AS TO WHETHER, AND WHICH PATIENTS WITH ASYMPTOMATIC HYPERURICEMIA WOULD WARRANT URATE-LOWERING TREATMENT. 2020 7 5480 33 RESVERATROL REVERSES MORPHINE-INDUCED NEUROINFLAMMATION IN MORPHINE-TOLERANT RATS BY REVERSAL HDAC1 EXPRESSION. BACKGROUND/PURPOSE: WE PREVIOUSLY SHOWED THAT SUBSEQUENT INTRATHECAL (I.T.) INJECTION OF RESVERATROL (30 MUG) SIGNIFICANTLY REVERSES MORPHINE-EVOKED NEUROINFLAMMATION IN MORPHINE-TOLERANT RATS. THE PRESENT STUDY EXAMINED THE UNDERLYING MECHANISM. METHODS: MALE WISTAR RATS WERE IMPLANTED WITH TWO I.T. CATHETERS, ONE OF WHICH WAS CONNECTED TO A MINIOSMOTIC PUMP AND USED FOR MORPHINE (15 MUG/H) OR SALINE INFUSION FOR 120 HOURS. TO EXAMINE THE EFFECTS ON SPINAL CORD EXPRESSION OF HISTONE DEACETYLASE 1 (HDAC1), THE INFLAMMATORY CYTOKINE TUMOR NECROSIS FACTOR-ALPHA (TNF-ALPHA), AND TNF RECEPTOR (TNFR) 1 AND TNFR2 DURING TOLERANCE INDUCTION, A TAIL-FLICK TEST WAS PERFORMED PRIOR TO INFUSION AND AFTER 24 HOURS, 48 HOURS, 72 HOURS, 96 HOURS, AND 120 HOURS OF INFUSION. RESULTS: RESVERATROL TREATMENT PRIOR TO MORPHINE CHALLENGE RESTORED THE ANTINOCICEPTIVE EFFECT OF MORPHINE IN MORPHINE-TOLERANT RATS AND REVERSED THE MORPHINE INFUSION-INDUCED INCREASE IN HDAC1, TNF-ALPHA, AND TNFR1 EXPRESSION. MOREOVER, CHRONIC MORPHINE INFUSION INCREASED TNFR1-SPECIFIC EXPRESSION IN NEURON IN MORPHINE-TOLERANT RAT SPINAL CORDS, AND THIS EFFECT WAS ALMOST COMPLETELY INHIBITED BY RESVERATROL TREATMENT PRIOR TO MORPHINE CHALLENGE. CONCLUSION: RESVERATROL RESTORES THE ANTINOCICEPTIVE EFFECT OF MORPHINE BY REVERSING MORPHINE INFUSION-INDUCED SPINAL CORD NEUROINFLAMMATION AND INCREASE IN TNFR1 EXPRESSION. THE REVERSAL OF THE MORPHINE-INDUCED INCREASE IN TNFR1 EXPRESSION BY RESVERATROL IS PARTIALLY DUE TO REVERSAL OF THE MORPHINE INFUSION-INDUCED INCREASE IN HDAC1 EXPRESSION. RESVERATROL PRETREATMENT CAN BE USED AS AN ADJUVANT IN CLINICAL PAIN MANAGEMENT FOR PATIENTS WHO NEED LONG-TERM MORPHINE TREATMENT OR WITH NEUROPATHIC PAIN. 2016 8 743 39 CANNABINOID TYPE 2 RECEPTOR SYSTEM MODULATES PACLITAXEL-INDUCED MICROGLIAL DYSREGULATION AND CENTRAL SENSITIZATION IN RATS. PACLITAXEL INDUCES MICROGLIAL ACTIVATION AND PRODUCTION OF PROINFLAMMATORY MEDIATORS IN THE DORSAL HORN, WHICH CONTRIBUTE TO THE DEVELOPMENT AND MAINTENANCE OF CENTRAL SENSITIZATION AND PAIN BEHAVIOR. MDA7, 1-([3-BENZYL-3-METHYL-2,3-DIHYDRO-1-BENZOFURAN-6-YL]CARBONYL) PIPERIDINE, IS A NOVEL HIGHLY SELECTIVE CANNABINOID TYPE 2 (CB2) AGONIST. WE TESTED THE HYPOTHESIS THAT ACTIVATION OF CB2 RECEPTOR BY MDA7 MODULATES MICROGLIAL DYSREGULATION, SUPPRESSES THE OVEREXPRESSION OF BRAIN-DERIVED NEUROTROPHIC FACTOR (BDNF) IN MICROGLIA IN THE DORSAL HORN, AND ATTENUATES THE CENTRAL SENSITIZATION AND PAIN BEHAVIOR INDUCED BY PACLITAXEL. FOR 4 CONSECUTICE DAYS, GROUPS OF RATS RANDOMLY RECEIVED SALINE OR 1.0 MG/KG OF PACLITAXEL DAILY INTRAPERITONEALLY FOR A TOTAL CUMULATIVE DOSE OF 4 MG/KG. MDA7 15 MG/KG INTRAPERITONEALLY OR VEHICLE WERE ADMINISTERED 15 MIN BEFORE ADMINISTERING PACLITAXEL FOR 4 DAYS AND THEN CONTINUED FOR ANOTHER 10 DAYS. BEHAVIORAL AND MOLECULAR STUDIES WERE PERFORMED. PACLITAXEL INDUCED THE EXPRESSION OF CB2 RECEPTORS AND PRODUCTION OF INTERLEUKIN (IL)-6 IN MICROGLIA IN THE DORSAL HORN. MDA7 ATTENUATED THE EXPRESSION OF IL-6 AND PROMOTED THE EXPRESSION OF IL-10. PACLITAXEL INDUCED EPIGENETIC UPREGULATION OF IRF8 AND P2X PURINOCEPTOR 4 (P2X4) IN MICROGLIA AND SUBSEQUENTLY INCREASED THE EXPRESSION OF ALPHA ISOFORM OF CALCIUM/CALMODULIN-DEPENDENT PROTEIN KINASE II (CAMKIIALPHA), TRANSCRIPTIONAL FACTORS P-CREB AND DELTAFOSB, LEADING TO THE OVERPRODUCTION OF BDNF IN MICROGLIA. PACLITAXEL ALSO UPREGULATED THE EXPRESSION OF GLUTAMATE RECEPTOR SUBUNITS GLUR1 AND NR2B, DECREASED THE EXPRESSION OF K(+)-CL(-) COTRANSPORTER, AND INDUCED MECHANICAL ALLODYNIA IN RATS. ALL OF THE AFOREMENTIONED MOLECULAR CHANGES WERE ATTENUATED BY MDA7. OUR DATA SHOW THAT MDA7 ATTENUATED PACLITAXEL-INDUCED MOLECULAR AND BEHAVIORAL CHANGES IN RATS. PERSPECTIVE: THIS STUDY PROVIDES EVIDENCE THAT PACLITAXEL INDUCED MICROGLIA DYSREGULATION AND EPIGENETICALLY UPREGULATED THE MICROGLIAL EXPRESSION OF BDNF, WHICH LED TO SENSITIZATION OF DORSAL HORN NEURONS AND MECHANICAL ALLODYNIA IN RATS. THE CB2 AGONIST MDA7 ALLEVIATED THESE PATHOLOGICAL PROCESSES. MDA7 REPRESENTS AN INNOVATIVE THERAPEUTIC APPROACH FOR TREATMENT OF CHEMOTHERAPY-INDUCED NEUROPATHY. 2019 9 2326 40 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 10 5657 35 SEX-DEPENDENT PRONOCICEPTIVE ROLE OF SPINAL ALPHA(5) -GABA(A) RECEPTOR AND ITS EPIGENETIC REGULATION IN NEUROPATHIC RODENTS. EXTRASYNAPTIC ALPHA(5) -SUBUNIT CONTAINING GABA(A) (ALPHA(5) -GABA(A) ) RECEPTORS PARTICIPATE IN CHRONIC PAIN. PREVIOUSLY, WE REPORTED A SEX DIFFERENCE IN THE ACTION OF ALPHA(5) -GABA(A) RECEPTORS IN DYSFUNCTIONAL PAIN. HOWEVER, THE UNDERLYING MECHANISMS REMAIN UNKNOWN. THE AIM OF THIS STUDY WAS TO EXAMINE THIS SEXUAL DIMORPHISM IN NEUROPATHIC RODENTS AND THE MECHANISMS INVOLVED. FEMALE AND MALE WISTAR RATS OR ICR MICE WERE SUBJECTED TO NERVE INJURY FOLLOWED BY ALPHA(5) -GABA(A) RECEPTOR INVERSE AGONIST INTRATHECAL ADMINISTRATION, L-655,708. THE DRUG PRODUCED AN ANTIALLODYNIC EFFECT IN NERVE-INJURED FEMALE RATS AND MICE, AND A LOWER EFFECT IN MALES. WE HYPOTHESIZED THAT CHANGES IN ALPHA(5) -GABA(A) RECEPTOR, PROBABLY INFLUENCED BY HORMONAL AND EPIGENETIC STATUS, MIGHT UNDERLIE THIS SEX DIFFERENCE. THUS, WE PERFORMED QPCR AND WESTERN BLOT. NERVE INJURY INCREASED ALPHA(5) -GABA(A) MRNA AND PROTEIN IN FEMALE DORSAL ROOT GANGLIA (DRG) AND DECREASED THEM IN DRG AND SPINAL CORD OF MALES. TO INVESTIGATE THE HORMONAL INFLUENCE OVER ALPHA(5) -GABA(A) RECEPTOR ACTIONS, WE PERFORMED NERVE INJURY TO OVARIECTOMIZED RATS AND RECONSTITUTED THEM WITH 17BETA-ESTRADIOL (E2). OVARIECTOMY ABROGATED L-655,708 ANTIALLODYNIC EFFECT AND E2 RESTORED IT. OVARIECTOMY DECREASED ALPHA(5) -GABA(A) RECEPTOR AND ESTROGEN RECEPTOR ALPHA PROTEIN IN DRG OF NEUROPATHIC FEMALE RATS, WHILE E2 ENHANCED THEM. SINCE DNA METHYLATION MIGHT CONTRIBUTE TO ALPHA(5) -GABA(A) RECEPTOR DOWN-REGULATION IN MALES, WE EXAMINED CPG ISLAND DNA METHYLATION OF ALPHA(5) -GABA(A) RECEPTOR CODING GENE THROUGH PYROSEQUENCING. NERVE INJURY INCREASED METHYLATION IN MALE, BUT NOT FEMALE RATS. PHARMACOLOGICAL INHIBITION OF DNA METHYLTRANSFERASES INCREASED ALPHA(5) -GABA(A) RECEPTOR AND ENABLED L-655,708 ANTINOCICEPTIVE EFFECT IN MALE RATS. THESE RESULTS SUGGEST THAT ALPHA(5) -GABA(A) RECEPTOR IS A SUITABLE TARGET TO TREAT CHRONIC PAIN IN FEMALES. 2021 11 4699 34 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 12 742 35 CANNABINOID CB2 RECEPTORS ARE UPREGULATED VIA BIVALENT HISTONE MODIFICATIONS AND CONTROL PRIMARY AFFERENT INPUT TO THE SPINAL CORD IN NEUROPATHIC PAIN. TYPE-2 CANNABINOID RECEPTORS (CB2, ENCODED BY THE CNR2 GENE) ARE MAINLY EXPRESSED IN IMMUNE CELLS, AND CB2 AGONISTS NORMALLY HAVE NO ANALGESIC EFFECT. HOWEVER, NERVE INJURY UPREGULATES CB2 IN THE DORSAL ROOT GANGLION (DRG), FOLLOWING WHICH CB2 STIMULATION REDUCES NEUROPATHIC PAIN. IT IS UNCLEAR HOW NERVE INJURY INCREASES CB2 EXPRESSION OR HOW CB2 ACTIVITY IS TRANSFORMED IN NEUROPATHIC PAIN. IN THIS STUDY, IMMUNOBLOTTING SHOWED THAT SPINAL NERVE LIGATION (SNL) INDUCED A DELAYED AND SUSTAINED INCREASE IN CB2 EXPRESSION IN THE DRG AND DORSAL SPINAL CORD SYNAPTOSOMES. RNASCOPE IN SITU HYBRIDIZATION ALSO SHOWED THAT SNL SUBSTANTIALLY INCREASED CB2 MRNA LEVELS, MOSTLY IN MEDIUM AND LARGE DRG NEURONS. FURTHERMORE, WE FOUND THAT THE SPECIFIC CB2 AGONIST JWH-133 SIGNIFICANTLY INHIBITS THE AMPLITUDE OF DORSAL ROOT-EVOKED GLUTAMATERGIC EXCITATORY POSTSYNAPTIC CURRENTS IN SPINAL DORSAL HORN NEURONS IN SNL RATS, BUT NOT IN SHAM CONTROL RATS; INTRATHECAL INJECTION OF JWH-133 REVERSED PAIN HYPERSENSITIVITY IN SNL RATS, BUT HAD NO EFFECT IN SHAM CONTROL RATS. IN ADDITION, CHROMATIN IMMUNOPRECIPITATION-QPCR ANALYSIS SHOWED THAT SNL INCREASED ENRICHMENT OF TWO ACTIVATING HISTONE MARKS (H3K4ME3 AND H3K9AC) AND DIMINISHED OCCUPANCY OF TWO REPRESSIVE HISTONE MARKS (H3K9ME2 AND H3K27ME3) AT THE CNR2 PROMOTER IN THE DRG. IN CONTRAST, SNL HAD NO EFFECT ON DNA METHYLATION LEVELS AROUND THE CNR2 PROMOTER. OUR FINDINGS SUGGEST THAT PERIPHERAL NERVE INJURY PROMOTES CB2 EXPRESSION IN PRIMARY SENSORY NEURONS VIA EPIGENETIC BIVALENT HISTONE MODIFICATIONS AND THAT CB2 ACTIVATION REDUCES NEUROPATHIC PAIN BY ATTENUATING NOCICEPTIVE TRANSMISSION FROM PRIMARY AFFERENT NERVES TO THE SPINAL CORD. 2022 13 6612 32 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 14 2272 35 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 15 4172 30 MELATONIN IMPEDES TET1-DEPENDENT MGLUR5 PROMOTER DEMETHYLATION TO RELIEVE PAIN. MELATONIN (N-ACETYL-5-METHOXYTRYPTAMINE)/MT2 RECEPTOR-DEPENDENT EPIGENETIC MODIFICATION REPRESENTS A NOVEL PATHWAY IN THE TREATMENT OF NEUROPATHIC PAIN. BECAUSE SPINAL TEN-ELEVEN TRANSLOCATION METHYLCYTOSINE DIOXYGENASE 1 (TET1)-DEPENDENT EPIGENETIC DEMETHYLATION HAS RECENTLY BEEN LINKED TO PAIN HYPERSENSITIVITY, WE HYPOTHESIZED THAT MELATONIN/MT2-DEPENDENT ANALGESIA INVOLVES SPINAL TET1-DEPENDENT DEMETHYLATION. HERE, WE SHOWED THAT SPINAL TET1 GENE TRANSFER BY INTRATHECAL DELIVERY OF TET1-ENCODING VECTORS TO NAIVE RATS PRODUCED PROFOUND AND LONG-LASTING NOCICEPTIVE HYPERSENSITIVITY. IN ADDITION, ENHANCED TET1 EXPRESSION, TET1-METABOTROPIC GLUTAMATE RECEPTOR SUBTYPE 5 (MGLUR5) PROMOTER COUPLING, DEMETHYLATION AT THE MGLUR5 PROMOTER, AND MGLUR5 EXPRESSION IN DORSAL HORN NEURONS WERE OBSERVED. RATS SUBJECTED TO SPINAL NERVE LIGATION AND INTRAPLANTAR COMPLETE FREUND'S ADJUVANT INJECTION DISPLAYED TACTILE ALLODYNIA AND BEHAVIORAL HYPERALGESIA ASSOCIATED WITH SIMILAR CHANGES IN THE DORSAL HORN. NOTABLY, INTRATHECAL MELATONIN INJECTION REVERSED THE PROTEIN EXPRESSION, PROTEIN-PROMOTER COUPLING, PROMOTER DEMETHYLATION, AND PAIN HYPERSENSITIVITY INDUCED BY TET1 GENE TRANSFER, SPINAL NERVE LIGATION, AND INTRAPLANTAR COMPLETE FREUND'S ADJUVANT INJECTION. ALL THE EFFECTS CAUSED BY MELATONIN WERE BLOCKED BY PRETREATMENT WITH A MT2 RECEPTOR-SELECTIVE ANTAGONIST. IN CONCLUSION, MELATONIN RELIEVES PAIN BY IMPEDING TET1-DEPENDENT DEMETHYLATION OF MGLUR5 IN DORSAL HORN NEURONS THROUGH THE MT2 RECEPTOR. OUR FINDINGS LINK MELATONIN/MT2 SIGNALING TO TET1-DEPENDENT EPIGENETIC DEMETHYLATION OF NOCICEPTIVE GENES FOR THE FIRST TIME AND SUGGEST MELATONIN AS A PROMISING THERAPY FOR THE TREATMENT OF PAIN. 2017 16 3869 32 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 17 4304 47 MICRORNA-223 PROTECTS NEURONS FROM DEGENERATION IN EXPERIMENTAL AUTOIMMUNE ENCEPHALOMYELITIS. MULTIPLE SCLEROSIS IS A CHRONIC INFLAMMATORY, DEMYELINATING, AND NEURODEGENERATIVE DISEASE AFFECTING THE BRAIN, SPINAL CORD AND OPTIC NERVES. NEURONAL DAMAGE IS TRIGGERED BY VARIOUS HARMFUL FACTORS THAT ENGAGE DIVERSE SIGNALLING CASCADES IN NEURONS; THUS, THERAPEUTIC APPROACHES TO PROTECT NEURONS WILL NEED TO FOCUS ON AGENTS THAT CAN TARGET MULTIPLE BIOLOGICAL PROCESSES. WE HAVE THEREFORE FOCUSED OUR ATTENTION ON MICRORNAS: SMALL NON-CODING RNAS THAT PRIMARILY FUNCTION AS POST-TRANSCRIPTIONAL REGULATORS THAT TARGET MESSENGER RNAS AND REPRESS THEIR TRANSLATION INTO PROTEINS. A SINGLE MICRORNA CAN TARGET MANY FUNCTIONALLY RELATED MESSENGER RNAS MAKING MICRORNAS POWERFUL EPIGENETIC REGULATORS. DYSREGULATION OF MICRORNAS HAS BEEN DESCRIBED IN MANY NEURODEGENERATIVE DISEASES INCLUDING MULTIPLE SCLEROSIS. HERE, WE REPORT THAT TWO MICRORNAS, MIR-223-3P AND MIR-27A-3P, ARE UPREGULATED IN NEURONS IN THE EXPERIMENTAL AUTOIMMUNE ENCEPHALOMYELITIS MOUSE MODEL OF CNS INFLAMMATION AND IN GREY MATTER-CONTAINING MULTIPLE SCLEROSIS LESIONS. PRIOR WORK HAS SHOWN PERIPHERAL BLOOD MONONUCLEAR CELL CONDITIONED MEDIA CAUSES SUBLETHAL DEGENERATION OF NEURONS IN CULTURE. WE FIND OVEREXPRESSION OF MIR-27A-3P OR MIR-223-3P PROTECTS DISSOCIATED CORTICAL NEURONS FROM CONDITION MEDIA MEDIATED DEGENERATION. INTRODUCTION OF MIR-223-3P IN VIVO IN MOUSE RETINAL GANGLION CELLS PROTECTS THEIR AXONS FROM DEGENERATION IN EXPERIMENTAL AUTOIMMUNE ENCEPHALOMYELITIS. IN SILICO ANALYSIS REVEALED THAT MESSENGER RNAS INVOLVED IN GLUTAMATE RECEPTOR SIGNALLING ARE ENRICHED AS MIR-27A-3P AND MIR-223-3P TARGETS. WE OBSERVE THAT ANTAGONISM OF NMDA AND AMPA TYPE GLUTAMATE RECEPTORS PROTECTS NEURONS FROM CONDITION MEDIA DEPENDENT DEGENERATION. OUR RESULTS SUGGEST THAT MIR-223-3P AND MIR-27A-3P ARE UPREGULATED IN RESPONSE TO INFLAMMATION TO MEDIATE A COMPENSATORY NEUROPROTECTIVE GENE EXPRESSION PROGRAM THAT DESENSITIZES NEURONS TO GLUTAMATE BY TARGETING MESSENGER RNAS INVOLVED IN GLUTAMATE RECEPTOR SIGNALLING. 2019 18 5868 49 SUPPRESSIVE EFFECTS OF METFORMIN ON T-HELPER 1-RELATED CHEMOKINES EXPRESSION IN THE HUMAN MONOCYTIC LEUKEMIA CELL LINE THP-1. PURPOSE OF THE STUDY: TYPE 1 AND TYPE 2 DIABETES MELLITUS (DM) ARE CHRONIC T-CELL-MEDIATED INFLAMMATORY DISEASES. METFORMIN IS A WIDELY USED DRUG FOR TYPE 2 DM THAT REDUCES THE NEED FOR INSULIN IN TYPE 1 DM. HOWEVER, WHETHER METFORMIN HAS AN ANTI-INFLAMMATORY EFFECT FOR TREATING DM IS UNKNOWN. WE INVESTIGATED THE ANTI-INFLAMMATORY MECHANISM OF METFORMIN IN THE HUMAN MONOCYTIC LEUKEMIA CELL LINE THP-1. MATERIALS AND METHODS: THE HUMAN MONOCYTIC LEUKEMIA CELL LINE THP-1 WAS PRETREATED WITH METFORMIN AND STIMULATED WITH LIPOPOLYSACCHARIDE (LPS). THE PRODUCTION OF T-HELPER (TH)-1-RELATED CHEMOKINES INCLUDING INTERFERON-GAMMA-INDUCED PROTEIN-10 (IP-10) AND MONOCYTE CHEMOATTRACTANT PROTEIN-1 (MCP-1), TH2-RELATED CHEMOKINE MACROPHAGE-DERIVED CHEMOKINE, AND THE PROINFLAMMATORY CHEMOKINE TUMOR NECROSIS FACTOR-ALPHA WAS MEASURED USING ENZYME-LINKED IMMUNOSORBENT ASSAY. INTRACELLULAR SIGNALING PATHWAYS WERE INVESTIGATED USING WESTERN BLOT ANALYSIS AND CHROMATIN IMMUNOPRECIPITATION ASSAY. RESULTS: METFORMIN SUPPRESSED LPS-INDUCED IP-10 AND MCP-1 PRODUCTION AS WELL AS LPS-INDUCED PHOSPHORYLATION OF C-JUN N-TERMINAL KINASE (JNK), P38, EXTRACELLULAR SIGNAL-REGULATED KINASE (ERK), AND NUCLEAR FACTOR-KAPPA B (NF-KAPPAB). MOREOVER, METFORMIN SUPPRESSED LPS-INDUCED ACETYLATION OF HISTONES H3 AND H4 AT THE IP-10 PROMOTER. CONCLUSIONS: METFORMIN SUPPRESSED THE PRODUCTION OF TH1-RELATED CHEMOKINES IP-10 AND MCP-1 IN THP-1 CELLS. SUPPRESSIVE EFFECTS OF METFORMIN ON IP-10 PRODUCTION MIGHT BE ATTRIBUTED AT LEAST PARTIALLY TO THE JNK, P38, ERK, AND NF-KAPPAB PATHWAYS AS WELL AS TO EPIGENETIC REGULATION THROUGH THE ACETYLATION OF HISTONES H3 AND H4. THESE RESULTS INDICATED THE THERAPEUTIC ANTI-INFLAMMATORY POTENTIAL OF METFORMIN. 2018 19 4303 50 MICRORNA-223 INHIBITS TISSUE FACTOR EXPRESSION IN VASCULAR ENDOTHELIAL CELLS. OBJECTIVE: ATHEROSCLEROSIS IS A CHRONIC INFLAMMATORY PROCESS, IN WHICH VASCULAR ENDOTHELIAL CELLS (ECS) BECOME DYSFUNCTIONAL OWING TO THE EFFECTS OF CHEMICAL SUBSTANCES, SUCH AS INFLAMMATORY FACTOR AND GROWTH FACTORS. TISSUE FACTOR (TF) EXPRESSION IS INDUCED BY THE ABOVE CHEMICAL SUBSTANCES IN ACTIVATED ECS. TF INITIATES THROMBOSIS ON DISRUPTED ATHEROSCLEROTIC PLAQUES WHICH PLAYS AN ESSENTIAL ROLE DURING THE ONSET OF ACUTE CORONARY SYNDROMES (ACS). INCREASING EVIDENCES SUGGEST THE IMPORTANT ROLE OF MICRORNAS AS EPIGENETIC REGULATORS OF ATHEROSCLEROTIC DISEASE. THE AIM OF OUR STUDY IS TO IDENTIFY IF MICRORNA-223 (MIR-223) TARGETS TF IN ECS. METHODS AND RESULTS: BIOINFORMATIC ANALYSIS SHOWED THAT TF IS A TARGET CANDIDATE OF MIR-223. WESTERN BLOTTING ANALYSIS REVEALED THAT TUMOR NECROSIS FACTOR ALPHA (TNF-ALPHA) INCREASED TF EXPRESSION IN AORTA OF C57BL/6J MICE AND CULTURED ECS (EA.HY926 CELLS AND HUVEC) AFTER 4 H TREATMENT. IN TNF-ALPHA TREATED ECS, TF MRNA WAS ALSO INCREASED MEASURED BY REAL-TIME PCR. REAL-TIME PCR RESULTS SHOWED THAT MIR-223 LEVELS WERE DOWNREGULATED IN TNF-ALPHA-TREATED AORTA OF C57BL/6J MICE AND CULTURED ECS. TRANSFECTION OF ECS WITH MIR-223 MIMIC OR MIR-223 INHIBITOR MODIFIED TF EXPRESSION BOTH IN MRNA AND PROTEIN LEVELS. LUCIFERASE ASSAYS CONFIRMED THAT MIR-223 SUPPRESSED TF EXPRESSION BY BINDING TO THE SEQUENCE OF TF 3'-UNTRANSLATED REGIONS (3'UTR). TF PROCOAGULANT ACTIVITY WAS INHIBITED BY OVEREXPRESSING MIR-223 WITH OR WITHOUT TNF-ALPHA STIMULATION. CONCLUSIONS: MIR-223-MEDIATED SUPPRESSION OF TF EXPRESSION PROVIDES A NOVEL MOLECULAR MECHANISM FOR THE REGULATION OF COAGULATION CASCADE, AND SUGGESTS A CLUE AGAINST THROMBOGENESIS DURING THE PROCESS OF ATHEROSCLEROTIC PLAQUE RUPTURE. 2014 20 4212 39 METHAMPHETAMINE DOWNREGULATES STRIATAL GLUTAMATE RECEPTORS VIA DIVERSE EPIGENETIC MECHANISMS. BACKGROUND: CHRONIC METHAMPHETAMINE (METH) EXPOSURE CAUSES NEUROADAPTATIONS AT GLUTAMATERGIC SYNAPSES. METHODS: TO IDENTIFY THE METH-INDUCED EPIGENETIC UNDERPINNINGS OF THESE NEUROADAPTATIONS, WE INJECTED INCREASING METH DOSES TO RATS FOR 2 WEEKS AND MEASURED STRIATAL GLUTAMATE RECEPTOR EXPRESSION. WE THEN QUANTIFIED THE EFFECTS OF METH EXPOSURE ON HISTONE ACETYLATION. WE ALSO MEASURED METH-INDUCED CHANGES IN DNA METHYLATION AND DNA HYDROXYMETHYLATION. RESULTS: CHRONIC METH DECREASED TRANSCRIPT AND PROTEIN EXPRESSION OF GLUA1 AND GLUA2 ALPHA-AMINO-3-HYDROXY-5-METHYL-4-ISOXAZOLE PROPIONIC ACID RECEPTOR (AMPAR) AND GLUN1 N-METHYL-D-ASPARTATE RECEPTOR SUBUNITS. THESE CHANGES WERE ASSOCIATED WITH ALTERED ELECTROPHYSIOLOGICAL GLUTAMATERGIC RESPONSES IN STRIATAL NEURONS. CHROMATIN IMMUNOPRECIPITATION-POLYMERASE CHAIN REACTION REVEALED THAT METH DECREASED ENRICHMENT OF ACETYLATED HISTONE H4 ON GLUA1, GLUA2, AND GLUN1 PROMOTERS. METHAMPHETAMINE EXPOSURE ALSO INCREASED REPRESSOR ELEMENT-1 SILENCING TRANSCRIPTION FACTOR (REST) COREPRESSOR 1, METHYLATED CPG BINDING PROTEIN 2, AND HISTONE DEACETYLASE 2 ENRICHMENT, BUT NOT OF SIRTUIN 1 OR SIRTUIN 2, ONTO GLUA1 AND GLUA2 GENE SEQUENCES. MOREOVER, METH CAUSED INTERACTIONS OF REST COREPRESSOR 1 AND METHYLATED CPG BINDING PROTEIN 2 WITH HISTONE DEACETYLASE 2 AND OF REST WITH HISTONE DEACETYLASE 1. SURPRISINGLY, METHYLATED DNA IMMUNOPRECIPITATION AND HYDROXYMETHYLATED DNA IMMUNOPRECIPITATION-POLYMERASE CHAIN REACTION REVEALED METH-INDUCED DECREASED ENRICHMENT OF 5-METHYLCYTOSINE AND 5-HYDROXYMETHYLCYTOSINE AT GLUA1 AND GLUA2 PROMOTER SEQUENCES. IMPORTANTLY, THE HISTONE DEACETYLASE INHIBITOR, VALPROIC ACID, BLOCKED METH-INDUCED DECREASED EXPRESSION OF AMPAR AND N-METHYL-D-ASPARTATE RECEPTOR SUBUNITS. FINALLY, VALPROIC ACID ALSO ATTENUATED METH-INDUCED DECREASE H4K16AC RECRUITMENT ON AMPAR GENE SEQUENCES. CONCLUSIONS: THESE OBSERVATIONS SUGGEST THAT HISTONE H4 HYPOACETYLATION MAY BE THE MAIN DETERMINANT OF METH-INDUCED DECREASED STRIATAL GLUTAMATE RECEPTOR EXPRESSION. 2014