1 5714 127 SIRT3 OVEREXPRESSION AND EPIGENETIC SILENCING OF CATALASE REGULATE ROS ACCUMULATION IN CLL CELLS ACTIVATING AXL SIGNALING AXIS. MITOCHONDRIAL METABOLISM IS THE KEY SOURCE FOR ABUNDANT ROS IN CHRONIC LYMPHOCYTIC LEUKEMIA (CLL) CELLS. HERE, WE DETECTED SIGNIFICANTLY LOWER SUPEROXIDE ANION (O(2)(-)) LEVELS WITH INCREASED ACCUMULATION OF HYDROGEN PEROXIDE (H(2)O(2)) IN CLL CELLS VS. NORMAL B-CELLS. FURTHER ANALYSIS INDICATED THAT MITOCHONDRIAL SUPEROXIDE DISMUTASE (SOD)2, WHICH CONVERTS O(2)(-) INTO H(2)O(2) REMAINED DEACETYLATED IN CLL CELLS DUE TO SIRT3 OVEREXPRESSION RESULTING ITS CONSTITUTIVE ACTIVATION. IN ADDITION, CATALASE EXPRESSION WAS ALSO REDUCED IN CLL CELLS SUGGESTING IMPAIRMENT OF H(2)O(2)-CONVERSION INTO WATER AND O(2) WHICH MAY CAUSE H(2)O(2)-ACCUMULATION. IMPORTANTLY, WE IDENTIFIED TWO CPG-ISLANDS IN THE CATALASE PROMOTER AND DISCOVERED THAT WHILE THE DISTAL CPG-ISLAND (-3619 TO -3765) REMAINED METHYLATED IN BOTH NORMAL B-CELLS AND CLL CELLS, VARIABLE DEGREES OF METHYLATION WERE DISCERNIBLE IN THE PROXIMAL CPG-ISLAND (-174 TO -332) ONLY IN CLL CELLS. FINALLY, TREATMENT OF CLL CELLS WITH A DEMETHYLATING AGENT INCREASED CATALASE MRNA LEVELS. FUNCTIONALLY, ROS ACCUMULATION IN CLL CELLS ACTIVATED THE AXL SURVIVAL AXIS WHILE UPREGULATED SIRT3, SUGGESTING THAT CLL CELLS RAPIDLY REMOVE HIGHLY REACTIVE O(2)(-) TO AVOID ITS CYTOTOXIC EFFECT BUT MAINTAIN INCREASED H(2)O(2)-LEVEL TO PROMOTE CELL SURVIVAL. THEREFORE, ABROGATION OF ABERRANTLY ACTIVATED CELL SURVIVAL PATHWAYS USING ANTIOXIDANTS CAN BE AN EFFECTIVE INTERVENTION IN CLL THERAPY IN COMBINATION WITH CONVENTIONAL AGENTS. 2021 2 3865 31 JAK2 REGULATES MISMATCH REPAIR PROTEIN-MEDIATED EPIGENETIC ALTERATIONS IN RESPONSE TO OXIDATIVE DAMAGE. AT SITES OF CHRONIC INFLAMMATION EPITHELIAL CELLS UNDERGO ABERRANT DNA METHYLATION THAT CONTRIBUTES TO TUMORIGENESIS. INFLAMMATION IS ASSOCIATED WITH AN INCREASE IN REACTIVE OXYGEN SPECIES (ROS) THAT CAUSE OXIDATIVE DNA DAMAGE, WHICH HAS ALSO BEEN LINKED TO EPIGENETIC ALTERATIONS. WE PREVIOUSLY DEMONSTRATED THAT IN RESPONSE TO ROS, MISMATCH REPAIR PROTEINS MSH2 AND MSH6 RECRUIT EPIGENETIC SILENCING PROTEINS DNA METHYLTRANSFERASE 1 (DNMT1) AND POLYCOMB REPRESSIVE COMPLEX 2 (PRC2) MEMBERS TO SITES OF DNA DAMAGE, RESULTING IN TRANSCRIPTIONAL REPRESSION OF TUMOR SUPPRESSOR GENES (TSGS). HOWEVER, IT WAS UNCLEAR WHAT SIGNAL IS UNIQUE TO ROS THAT RESULTS IN THE CHROMATIN BINDING OF MSH2 AND MSH6. HEREIN, WE DEMONSTRATE THAT IN RESPONSE TO HYDROGEN PEROXIDE (H(2) O(2) ), JAK2 LOCALIZES TO THE NUCLEUS AND INTERACTS WITH MSH2 AND MSH6. INHIBITION OR KNOCKDOWN OF JAK2 REDUCES THE H(2) O(2) -INDUCED CHROMATIN INTERACTION OF MSH2, MSH6, DNMT1, AND PRC2 MEMBERS, REDUCES H(2) O(2) -INDUCED GLOBAL INCREASE IN TRIMETHYLATION OF LYSINE 27 OF HISTONE H3 (H3K27ME3), AND ABROGATES OXIDATIVE DAMAGE-INDUCED TRANSCRIPTIONAL REPRESSION OF CANDIDATE TSGS. MOREOVER, JAK2 MRNA EXPRESSION IS ASSOCIATED WITH CPG ISLAND METHYLATOR PHENOTYPE (CIMP) STATUS IN HUMAN COLORECTAL CANCER. OUR FINDINGS PROVIDE NOVEL INSIGHT INTO THE CONNECTION BETWEEN KINASE ACTIVATION AND EPIGENETIC ALTERATIONS DURING OXIDATIVE DAMAGE AND INFLAMMATION. ENVIRON. MOL. MUTAGEN. 60:308-319, 2019. (C) 2018 WILEY PERIODICALS, INC. 2019 3 1201 42 CORTICOTROPIN-RELEASING FACTOR RECEPTOR-1 MODULATES BIOMARKERS OF DNA OXIDATION IN ALZHEIMER'S DISEASE MICE. INCREASED PRODUCTION OF HYDROXYL RADICAL IS THE MAIN SOURCE OF OXIDATIVE DAMAGE IN MAMMALIAN DNA THAT ACCUMULATES IN ALZHEIMER'S DISEASE (AD). REACTIVE OXYGEN SPECIES (ROS) REACT WITH BOTH NUCLEAR DNA (NDNA) AND MITOCHONDRIAL DNA (MTDNA) TO GENERATE 8-HYDROXY-2'-DEOXYGUANOSINE (8-OHDG), BOTH OF WHICH CAN BE MEASURED IN THE URINE. KNOWLEDGE OF THIS PATHWAY HAS POSITIONED MEASUREMENT OF URINE 8-OHDG AS A RELIABLE INDEX OF DNA OXIDATION AND A POTENTIAL BIOMARKER TARGET FOR TRACKING EARLY CELLULAR DYSFUNCTION IN AD. FURTHERMORE, EPIGENETIC STUDIES DEMONSTRATE DECREASED GLOBAL DNA METHYLATION LEVELS (E.G. 5-METHYL-2'-DEOXYCYTIDINE, 5-MDC) IN AD TISSUES. MOREOVER, STRESS HORMONES CAN ACTIVATE NEURONAL OXIDATIVE STRESS WHICH WILL STIMULATE THE RELEASE OF ADDITIONAL STRESS HORMONES AND RESULT IN DAMAGES TO HIPPOCAMPAL NEURONS IN THE AD BRAIN. OUR PREVIOUS WORK SUGGESTS THAT TREATING AD TRANSGENIC MICE THE TYPE-1 CORTICOTROPIN-RELEASING FACTOR RECEPTOR (CRFR1) ANTAGONIST, R121919, TO REDUCE STRESS SIGNALING, PREVENTED ONSET OF COGNITIVE IMPAIRMENT, SYNAPTIC/DENDRITIC LOSS AND ABETA PLAQUE ACCUMULATION. THEREFORE, TO INVESTIGATE WHETHER LEVELS OF DNA OXIDATION CAN BE IMPACTED BY THE SAME THERAPEUTIC APPROACH, URINE LEVELS OF HYDROGEN PEROXIDE, 8-OHDG, 5-MDC AND TOTAL ANTIOXIDANT CAPACITY (TAC) WERE ANALYZED USING AN AD TG MOUSE MODEL. WE FOUND THAT TG ANIMALS HAD AN 80% INCREASE IN HYDROGEN PEROXIDE LEVELS COMPARED TO WILD TYPE (WT) COUNTERPARTS, AN EFFECT THAT COULD BE DRAMATICALLY REVERSED BY THE CHRONIC ADMINISTRATION WITH R121919. A SIGNIFICANT DECREASE OF 8-OHDG LEVELS WAS OBSERVED IN TG MICE TREATED WITH CRFR1 ANTAGONIST. COLLECTIVELY OUR DATA SUGGEST THAT THE BENEFICIAL EFFECTS OF CRFR1 ANTAGONISM SEEN IN TG MICE MAY BE MECHANISTICALLY LINKED TO THE MODULATION OF OXIDATIVE STRESS PATHWAYS. 2017 4 1353 32 DEVELOPMENT AND CHARACTERIZATION OF A HYDROGEN PEROXIDE-RESISTANT CHOLANGIOCYTE CELL LINE: A NOVEL MODEL OF OXIDATIVE STRESS-RELATED CHOLANGIOCARCINOMA GENESIS. OXIDATIVE STRESS IS A CAUSE OF INFLAMMATION-RELATED DISEASES, INCLUDING CANCERS. CHOLANGIOCARCINOMA IS A LIVER CANCER WITH BILE DUCT EPITHELIAL CELL PHENOTYPES. OUR PREVIOUS STUDIES IN ANIMAL AND HUMAN MODELS INDICATED THAT OXIDATIVE STRESS IS A MAJOR CAUSE OF CHOLANGIOCARCINOMA DEVELOPMENT. HYDROGEN PEROXIDE (H2O2) CAN GENERATE HYDROXYL RADICALS, WHICH DAMAGE LIPIDS, PROTEINS, AND NUCLEIC ACIDS, LEADING TO CELL DEATH. HOWEVER, SOME CELLS CAN SURVIVE BY ADAPTING TO OXIDATIVE STRESS CONDITIONS, AND SELECTIVE CLONAL EXPANSION OF THESE RESISTANT CELLS WOULD BE INVOLVED IN OXIDATIVE STRESS-RELATED CARCINOGENESIS. THE PRESENT STUDY AIMED TO ESTABLISH H2O2-RESISTANT CELL LINE FROM AN IMMORTAL CHOLANGIOCYTE CELL LINE (MMNK1) BY CHRONIC TREATMENT WITH LOW-CONCENTRATION H2O2 (25 MUM). AFTER 72 DAYS OF INDUCTION, H2O2-RESISTANT CELL LINES (OX-MMNK1-L) WERE OBTAINED. THE OX-MMNK1-L CELL LINE SHOWED H2O2-RESISTANT PROPERTIES, INCREASING THE EXPRESSION OF THE ANTI-OXIDANT GENES CATALASE (CAT), SUPEROXIDE DISMUTASE-1 (SOD1), SUPEROXIDE DISMUTASE-2 (SOD2), AND SUPEROXIDE DISMUTASE-3 (SOD3) AND THE ENZYME ACTIVITIES OF CAT AND INTRACELLULAR SODS. FURTHERMORE, THE RESISTANT CELLS SHOWED INCREASED EXPRESSION LEVELS OF AN EPIGENETICS-RELATED GENE, DNA METHYLTRANSFERASE-1 (DNMT1), WHEN COMPARED TO THE PARENTAL CELLS. INTERESTINGLY, THE OX-MMNK1-L CELL LINE HAD A SIGNIFICANTLY HIGHER CELL PROLIFERATION RATE THAN THE MMNK1 NORMAL CELL LINE. MOREOVER, OX-MMNK1-L CELLS SHOWED PSEUDOPODIA FORMATION AND THE LOSS OF CELL-TO-CELL ADHESION (MULTI-LAYERS) UNDER ADDITIONAL OXIDATIVE STRESS (100 MUM H2O2). THESE FINDINGS SUGGEST THAT H2O2-RESISTANT CELLS CAN BE USED AS A MODEL OF OXIDATIVE STRESS-RELATED CHOLANGIOCARCINOMA GENESIS THROUGH MOLECULAR CHANGES SUCH AS ALTERATION OF GENE EXPRESSION AND EPIGENETIC CHANGES. 2015 5 4704 29 NITRATION OF DISTINCT TYROSINE RESIDUES CAUSES INACTIVATION OF HISTONE DEACETYLASE 2. HISTONE DEACETYLASES (HDACS) ARE KEY MOLECULES INVOLVED IN EPIGENETIC REGULATION OF GENE EXPRESSION. WE HAVE PREVIOUSLY DEMONSTRATED THAT OXIDATIVE STRESS CAUSED A REDUCTION IN HDAC2, RESULTING IN AMPLIFIED INFLAMMATION AND REDUCED CORTICOSTEROID RESPONSIVENESS. HERE WE SHOWED NITRATIVE/OXIDATIVE STRESS REDUCED HDAC2 EXPRESSION VIA NITRATION OF DISTINCT TYROSINE RESIDUES. PEROXYNITRITE, HYDROGEN PEROXIDE AND CIGARETTE SMOKE-CONDITIONED MEDIUM REDUCED HDAC2 EXPRESSION IN A549 EPITHELIAL CELLS IN VITRO. THIS REDUCTION WAS DUE TO INCREASED PROTEASOMAL DEGRADATION FOLLOWING UBIQUITINATION RATHER THAN REDUCTION OF MRNA EXPRESSION OR STABILITY. HDAC2 WAS NITRATED UNDER NITRATIVE/OXIDATIVE STRESS AND IN THE PERIPHERAL LUNG TISSUES OF SMOKERS AND PATIENTS WITH CHRONIC OBSTRUCTIVE PULMONARY DISEASE. MUTAGENESIS STUDIES REPLACING TYROSINE (Y) RESIDUES WITH ALANINE REVEALED THAT Y253 IS AT LEAST PARTLY RESPONSIBLE FOR THE PROTEASOMAL DEGRADATION OF HDAC2 UNDER NITRATIVE STRESS. THUS, NITRATION OF DISTINCT TYROSINE RESIDUES MODIFIES BOTH THE EXPRESSION AND ACTIVITY OF HDAC2, HAVING AN IMPACT ON EPIGENETIC REGULATION. 2009 6 4374 28 MISMATCH REPAIR PROTEINS RECRUIT DNA METHYLTRANSFERASE 1 TO SITES OF OXIDATIVE DNA DAMAGE. AT SITES OF CHRONIC INFLAMMATION, EPITHELIAL CELLS ARE EXPOSED TO HIGH LEVELS OF REACTIVE OXYGEN SPECIES AND UNDERGO CANCER-ASSOCIATED DNA METHYLATION CHANGES, SUGGESTING THAT INFLAMMATION MAY INITIATE EPIGENETIC ALTERATIONS. PREVIOUSLY, WE DEMONSTRATED THAT OXIDATIVE DAMAGE CAUSES EPIGENETIC SILENCING PROTEINS TO BECOME PART OF A LARGE COMPLEX THAT IS LOCALIZED TO GC-RICH REGIONS OF THE GENOME, INCLUDING PROMOTER CPG ISLANDS THAT ARE EPIGENETICALLY SILENCED IN CANCER. HOWEVER, WHETHER THESE PROTEINS WERE RECRUITED DIRECTLY TO DAMAGED DNA OR DURING THE DNA REPAIR PROCESS WAS UNKNOWN. HERE WE DEMONSTRATE THAT THE MISMATCH REPAIR PROTEIN HETERODIMER MSH2-MSH6 PARTICIPATES IN THE OXIDATIVE DAMAGE-INDUCED RECRUITMENT OF DNA METHYLTRANSFERASE 1 (DNMT1) TO CHROMATIN. HYDROGEN PEROXIDE TREATMENT INDUCES THE INTERACTION OF MSH2-MSH6 WITH DNMT1, SUGGESTING THAT THE RECRUITMENT IS THROUGH A PROTEIN-PROTEIN INTERACTION. IMPORTANTLY, THE REDUCTION IN TRANSCRIPTION FOR GENES WITH CPG ISLAND-CONTAINING PROMOTERS CAUSED BY OXIDATIVE DAMAGE IS ABROGATED BY KNOCKDOWN OF MSH6 AND/OR DNMT1. OUR FINDINGS PROVIDE EVIDENCE THAT THE ROLE OF DNMT1 AT SITES OF OXIDATIVE DAMAGE IS TO REDUCE TRANSCRIPTION, POTENTIALLY PREVENTING TRANSCRIPTION FROM INTERFERING WITH THE REPAIR PROCESS. THIS STUDY UNIQUELY BRINGS TOGETHER SEVERAL FACTORS THAT ARE KNOWN TO CONTRIBUTE TO COLON CANCER, NAMELY INFLAMMATION, MISMATCH REPAIR PROTEINS, AND EPIGENETIC CHANGES. 2016 7 3426 31 HUMAN UMBILICAL ARTERY ENDOTHELIAL CELLS FROM LARGE-FOR-GESTATIONAL-AGE NEWBORN HAVE INCREASED ANTIOXIDANT EFFICIENCY AND GENE EXPRESSION. OBESITY IS A PUBLIC HEALTH PROBLEM WORLDWIDE, AND ESPECIALLY IN WOMEN IN REPRODUCTIVE AGE WHERE MORE THAN ONE IN THREE HAVE OBESITY. MATERNAL OBESITY IS ASSOCIATED WITH AN INCREASED MATERNAL, PLACENTAL, AND NEWBORN OXIDATIVE STRESS, WHICH HAS BEEN PROPOSED AS A CENTRAL FACTOR IN VASCULAR DYSFUNCTION IN LARGE-FOR-GESTATIONAL-AGE (LGA) NEWBORN. HOWEVER, CELLULAR AND MOLECULAR MECHANISMS BEHIND THIS EFFECT HAVE NOT BEEN ELUCIDATED. UNTREATED HUMAN UMBILICAL ARTERY ENDOTHELIAL CELLS (HUAEC) FROM LGA (LGA-HUAEC) PRESENTED HIGHER O(2)(-) LEVELS, SUPEROXIDE DISMUTASE ACTIVITY AND HEME OXYGENASE 1 MESSENGER RNA (MRNA) LEVELS, PARALLELED BY REDUCED GSH:GSSG RATIO AND NRF2 MRNA LEVELS. IN RESPONSE TO AN OXIDATIVE CHALLENGE (HYDROGEN PEROXIDE), ONLY HUAEC FROM LGA EXHIBITED AN ENHANCED GLUTATHIONE PEROXIDASE 1 (GPX1) EXPRESSION, AS WELL AS A MORE EFFICIENT ANTIOXIDANT MACHINERY MEASURED BY THE BIOSENSOR PROBE, HYPER. AN OPEN STATE OF CHROMATIN IN THE TSS REGION OF GPX1 IN LGA-HUAEC WAS EVIDENCED BY THE DNASE-HS ASSAY. ALTOGETHER, OUR DATA INDICATE THAT LGA-HUAEC HAVE AN ALTERED CELLULAR AND MOLECULAR ANTIOXIDANT SYSTEM. WE PROPOSE THAT A CHRONIC PRO-OXIDANT INTRAUTERINE MILIEU, AS EVIDENCED IN PREGESTATIONAL OBESITY, COULD INDUCE A MORE EFFICIENT ANTIOXIDANT SYSTEM IN FETAL VASCULAR CELLS, WHICH COULD BE MAINTAINED BY EPIGENETIC MECHANISM DURING POSTNATAL LIFE. 2019 8 6456 24 THYMOSIN BETA4 PREVENTS OXIDATIVE STRESS, INFLAMMATION, AND FIBROSIS IN ETHANOL- AND LPS-INDUCED LIVER INJURY IN MICE. THYMOSIN BETA 4 (TBETA4), AN ACTIN-SEQUESTERING PROTEIN, IS INVOLVED IN TISSUE DEVELOPMENT AND REGENERATION. IT PREVENTS INFLAMMATION AND FIBROSIS IN SEVERAL TISSUES. WE INVESTIGATED THE ROLE OF TBETA4 IN CHRONIC ETHANOL- AND ACUTE LIPOPOLYSACCHARIDE- (LPS-) INDUCED MOUSE LIVER INJURY. C57BL/6 MICE WERE FED 5% ETHANOL IN LIQUID DIET FOR 4 WEEKS PLUS BINGE ETHANOL (5 G/KG, GAVAGE) WITH OR WITHOUT LPS (2 MG/KG, INTRAPERITONEAL) FOR 6 HOURS. TBETA4 (1 MG/KG, INTRAPERITONEAL) WAS ADMINISTERED FOR 1 WEEK. WE DEMONSTRATED THAT TBETA4 PREVENTED ETHANOL- AND LPS-MEDIATED INCREASE IN LIVER INJURY MARKERS AS WELL AS CHANGES IN LIVER PATHOLOGY. IT ALSO PREVENTED ETHANOL- AND LPS-MEDIATED INCREASE IN OXIDATIVE STRESS BY DECREASING ROS AND LIPID PEROXIDATION AND INCREASING THE ANTIOXIDANTS, REDUCED GLUTATHIONE AND MANGANESE-DEPENDENT SUPEROXIDE DISMUTASE. IT ALSO PREVENTED THE ACTIVATION OF NUCLEAR FACTOR KAPPA B BY BLOCKING THE PHOSPHORYLATION OF THE INHIBITORY PROTEIN, IKAPPAB, THEREBY PREVENTED PROINFLAMMATORY CYTOKINE PRODUCTION. MOREOVER, TBETA4 PREVENTED FIBROGENESIS BY SUPPRESSING THE EPIGENETIC REPRESSOR, METHYL-CPG-BINDING PROTEIN 2, THAT COORDINATELY REVERSED THE EXPRESSION OF PEROXISOME PROLIFERATOR-ACTIVATED RECEPTOR-GAMMA AND DOWNREGULATED FIBROGENIC GENES, PLATELET-DERIVED GROWTH FACTOR-BETA RECEPTOR, ALPHA-SMOOTH MUSCLE ACTIN, COLLAGEN 1, AND FIBRONECTIN, RESULTING IN REDUCED FIBROSIS. OUR DATA SUGGEST THAT TBETA4 HAS ANTIOXIDANT, ANTI-INFLAMMATORY, AND ANTIFIBROTIC POTENTIAL DURING ALCOHOLIC LIVER INJURY. 2018 9 5860 30 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 10 3449 35 HYPERMETHYLATION OF THE NRF2 PROMOTER INDUCES FERROPTOSIS BY INHIBITING THE NRF2-GPX4 AXIS IN COPD. BACKGROUND: NUCLEAR FACTOR E2-RELATED FACTOR 2 (NRF2) IS INVOLVED IN OXIDATIVE STRESS AND LUNG INFLAMMATION AND REGULATES THE ETIOLOGY OF CHRONIC OBSTRUCTIVE PULMONARY DISEASE (COPD). FERROPTOSIS IS CHARACTERIZED BY THE ACCUMULATION OF LIPID REACTIVE OXYGEN SPECIES (ROS) VIA FERROUS ION-DEPENDENT FENTON REACTIONS AND IS INVOLVED IN COPD. HOWEVER, THE ROLE OF NRF2 IN FERROPTOSIS AND ITS EPIGENETIC REGULATION IN THE PATHOGENESIS OF COPD REMAIN UNCLEAR. METHODS: FERROPTOSIS WAS DETECTED BY 4-HNE, MDA, C11BODIPY, DCFH-DA, PEALS' STAINING AND CCK-8 ASSAYS. QPCR AND WESTERN BLOTTING WERE PERFORMED TO EXAMINE THE NRF2 LEVELS IN PERIPHERAL LUNG TISSUES, PRIMARY EPITHELIAL CELLS COLLECTED FROM PATIENTS WITH COPD AND SUBJECTS WITH NORMAL PULMONARY FUNCTION (NEVER-SMOKER [CONTROL-NS]; SMOKER [CONTROL-S]), AND CIGARETTE SMOKE EXTRACT (CSE)-TREATED HUMAN BRONCHIAL EPITHELIAL (HBE) CELLS. ELISA WAS USED TO QUANTIFY IL-8 AND IL-1BETA LEVELS. METHYLATION OF THE NRF2 PROMOTER WAS ANALYZED BY BISULFITE SEQUENCING AND PYROSEQUENCING. RESULTS: FERROPTOSIS WAS INVOLVED IN COPD AND GLUTATHIONE PEROXIDASE 4 (GPX4) EXPRESSION WAS DOWNREGULATED IN THE COPD GROUP. REACTIVE OXYGEN SPECIES (ROS), LIPID PEROXIDES AND MDA WERE INCREASED, BUT GPX4 AND SOD WERE EXHAUSTED IN CSE-TREATED HBE CELLS. THE PRODUCTION OF IL-1BETA AND IL-8 WAS PROMOTED IN HBE CELLS IN RESPONSE TO CSE BUT COULD BE REVERSED BY THE FERROPTOSIS INHIBITOR FER-1. THE NRF2 LEVEL WAS SIGNIFICANTLY DECREASED IN THE COPD GROUP COMPARED WITH THE CONTROL-S AND CONTROL-NS GROUPS. INCREASED NRF2 EXPRESSION ENHANCED GPX4 AND SOD LEVELS AND INHIBITED FERROPTOSIS AND PROINFLAMMATORY CYTOKINES IN THE SUPERNATANT. INHIBITION OF GPX4 REVERSED THE EFFECT OF NRF2 OVEREXPRESSION AND PROMOTED FERROPTOSIS. TWO SPECIFIC CPG SITES WITHIN THE NRF2 PROMOTER WERE HYPERMETHYLATED IN THE COPD GROUP. SIMILARLY, CSE-TREATED HBE CELLS EXHIBITED HYPERMETHYLATION OF THE NRF2 GENE. CONCLUSION: NRF2 EXPRESSION WAS DOWNREGULATED IN THE LUNGS OF COPD PATIENTS DUE TO HYPERMETHYLATION OF THE NRF2 PROMOTER, INHIBITING NRF2/GPX4 AND FERROPTOSIS, WHICH IS RELATED TO THE INITIATION AND PROGRESSION OF COPD. TARGETING NRF2/GPX4 MAY INHIBIT FERROPTOSIS, WHICH COULD PROVIDE STRATEGIES TO DELAY OR TREAT COPD. 2021 11 5010 31 PEROXIDATION OF LINOLEIC, ARACHIDONIC AND OLEIC ACID IN RELATION TO THE INDUCTION OF OXIDATIVE DNA DAMAGE AND CYTOGENETIC EFFECTS. IN THE PRESENT STUDY, THE POSSIBLE ROLE OF THE POLYUNSATURATED FATTY ACIDS LINOLEIC AND ARACHIDONIC ACID IN THE CHEMICAL INDUCTION OF CARCINOGENESIS HAS BEEN INVESTIGATED. ANALYSIS OF 7,8-DIHYDRO-8-OXO-2'-DEOXYGUANOSINE (8-OXODG) LEVELS IN 2'-DEOXYGUANOSINE (DG) AND ISOLATED DNA HAS DEMONSTRATED THAT LINOLEIC AND ARACHIDONIC ACID ARE CAPABLE OF INDUCING THIS SPECIFIC GENOTOXIC DAMAGE. THIS EFFECT APPEARS TO BE RELATED TO THE DEGREE OF FATTY ACID UNSATURATION, SINCE IT WAS NOT INDUCED BY MONOUNSATURATED OLEIC ACID. ENZYMATIC PEROXIDATION OF LINOLEIC AND ARACHIDONIC ACID RESULTED IN A SIGNIFICANT INCREASE IN OXIDATIVE DNA DAMAGE. STUDIES ON THE INTERFERENCE OF RADICAL SCAVENGERS WITH THE INDUCTION OF 8-OXODG IN COMBINATION WITH ELECTRON SPIN RESONANCE SPECTROSCOPY DEMONSTRATED THAT THE SUPEROXIDE ANION WAS GENERATED DURING PEROXIDATION OF THESE FATTY ACIDS AND THAT SINGLET OXYGEN IS MOST LIKELY INVOLVED IN THE FORMATION OF OXIDATIVE DNA DAMAGE. THE LEVEL OF OXIDATIVE DAMAGE IN DG AND SINGLE-STRANDED DNA WAS HIGHER AS COMPARED TO THAT IN NATIVE DNA AFTER EQUIMOLAR TREATMENT. EXPOSURE OF HUMAN LYMPHOCYTES TO LINOLEIC OR ARACHIDONIC ACID DID NOT RESULT IN A SIGNIFICANT INCREASE IN LEVELS OF 8-OXODG. THIS MAY INDICATE THAT THE RATE OF INTRACELLULAR PEROXIDATION IS RELATIVELY LOW AND/OR THAT NUCLEAR DNA IN INTACT CELLS IS EFFECTIVELY PROTECTED AGAINST GENETIC DAMAGE INDUCED BY REACTIVE OXYGEN SPECIES. IT IS THEREFORE CONCLUDED THAT RELATIVELY SHORT PERIODS OF LINOLEIC OR ARACHIDONIC ACID ADMINISTRATION ARE NOT LIKELY TO IMPOSE A DIRECT GENOTOXIC RISK. IT CAN, HOWEVER, NOT BE EXCLUDED THAT CHRONIC EXPOSURE TO POLYUNSATURATED FATTY ACIDS INDUCES OXIDATIVE DNA DAMAGE OR IS RELATED TO CANCER RISK BY EPIGENETIC MECHANISMS, AS IS ALSO INDICATED BY THE OBSERVED CYTOTOXIC EFFECTS OF LINOLEIC AND ARACHIDONIC ACID. 1994 12 3723 30 INHIBITION OF DNA METHYLTRANSFERASE OR HISTONE DEACETYLASE PROTECTS RETINAL PIGMENT EPITHELIAL CELLS FROM DNA DAMAGE INDUCED BY OXIDATIVE STRESS BY THE STIMULATION OF ANTIOXIDANT ENZYMES. EPIGENETIC MODIFICATIONS INFLUENCE DNA DAMAGE RESPONSE (DDR). IN THIS STUDY WE EXPLORED THE ROLE OF DNA METHYLATION AND HISTONE ACETYLATION IN DDR IN CELLS CHALLENGED WITH ACUTE OR CHRONIC OXIDATIVE STRESS. WE USED RETINAL PIGMENT EPITHELIAL CELLS (ARPE-19), WHICH NATIVELY ARE EXPOSED TO OXIDATIVE STRESS DUE TO PERMANENT EXPOSURE TO LIGHT AND HIGH BLOOD FLOW. WE EMPLOYED A DNA METHYLTRANSFERASE INHIBITOR - RG108 (RG), OR A HISTONE DEACETYLASE INHIBITOR - VALPROIC ACID (VA). ARPE-19 CELLS WERE EXPOSED TO TERT-BUTYL HYDROPEROXIDE, AN ACUTE OXIDATIVE STRESS INDUCER, OR GLUCOSE OXIDASE, WHICH SLOWLY LIBERATES LOW-DOSES OF HYDROGEN PEROXIDE IN THE PRESENCE OF GLUCOSE, CREATING CHRONIC CONDITIONS. VA AND RG REDUCED LEVEL OF INTRACELLULAR REACTIVE OXYGEN SPECIES AND DNA DAMAGE IN ARPE-19 CELLS IN NORMAL CONDITION AND IN OXIDATIVE STRESS. THIS PROTECTIVE EFFECT OF VA AND RG WAS ASSOCIATED WITH THE UP-REGULATED EXPRESSION OF ANTIOXIDANT ENZYME GENES: CAT, GPX1, GPX4, SOD1 AND SOD2. RG DECREASED THE NUMBER OF CELLS IN G2/M CHECKPOINT IN RESPONSE TO CHRONIC OXIDATIVE STRESS. NEITHER RG NOR VA CHANGED THE DNA REPAIR OR APOPTOSIS INDUCED BY OXIDATIVE STRESS. THEREFORE, CERTAIN EPIGENETIC MANIPULATIONS MAY PROTECT ARPE-19 CELLS FROM DETRIMENTAL EFFECTS OF OXIDATIVE STRESS BY MODULATION OF ANTIOXIDATIVE ENZYME GENE EXPRESSION, WHICH MAY BE FURTHER EXPLORED IN PHARMACOLOGICAL STUDIES ON OXIDATIVE STRESS-RELATED EYE DISEASES. 2016 13 4044 25 MACROPHAGES IN OXIDATIVE STRESS AND MODELS TO EVALUATE THE ANTIOXIDANT FUNCTION OF DIETARY NATURAL COMPOUNDS. ANTIOXIDANT TESTING OF NATURAL PRODUCTS HAS ATTRACTED INCREASING INTEREST IN RECENT YEARS, MAINLY DUE TO THE FACT THAT AN ANTIOXIDANT-RICH DIET MIGHT PROVIDE HEALTH BENEFITS. ACTIVATED MACROPHAGES ARE A MAJOR SOURCE OF REACTIVE OXYGEN SPECIES, REACTIVE NITROGEN SPECIES, AND PEROXYNITRITE GENERATED THROUGH THE SO-CALLED RESPIRATORY BURST. CONSTITUTIVELY RELEASED PROINFLAMMATORY CYTOKINE, ESPECIALLY TUMOR NECROSIS FACTOR-ALPHA, TRIGGERS NUCLEAR FACTOR-KAPPAB, AND ACTIVATOR PROTEIN-1 TRANSLOCATION LEADING TO THE OVER PRODUCTION OF REACTIVE OXYGEN SPECIES AND REACTIVE NITROGEN SPECIES IN MACROPHAGES. ACTIVATION OF TRANSCRIPTION FACTORS IN THE LONG-LIVED TISSUE-RESIDENT MACROPHAGES AND/OR MONOCYTE-DERIVED MACROPHAGES, TRIGGER EPIGENETIC MODIFICATIONS LEADING TO THE PATHOGENESIS OF CHRONIC DISEASES. NUTRACEUTICALS INCLUDING LIPID RAFT STRUCTURE DISRUPTION AGENT, CHOLESTEROL DEPLETION AGENT, FARNESYLTRANSFERASE INHIBITOR, NUCLEAR FACTOR-KAPPAB BLOCKER (ALPHA,BETA-UNSATURATED CARBONYL COMPOUNDS), GLUCOCORTICOID RECEPTOR AGONIST, AND PEROXISOME PROLIFERATOR-ACTIVATED RECEPTOR-GAMMA AGONIST HAVE LONG BEEN USED TO INACTIVE MACROPHAGE. THE INHIBITION EFFECTS ON THE FORMATION OF NITRIC OXIDE, SUPEROXIDE, AND NITRITE PEROXIDE MAY BE RESPONSIBLE FOR THE ANTI-INFLAMMATORY FUNCTIONALITIES. ACTIVATED MACROPHAGE MODELS COULD BE USED TO IDENTIFY THE ACTIVE COMPONENTS FOR FUNCTIONAL DIETS DEVELOPMENT THROUGH A MULTIPLE TARGETS STRATEGY. 2017 14 5357 29 REACTIVE OXYGEN SPECIES INDUCE EPIGENETIC INSTABILITY THROUGH THE FORMATION OF 8-HYDROXYDEOXYGUANOSINE IN HUMAN HEPATOCARCINOGENESIS. CHRONIC HEPATITIS C (CHC) TRIGGERS OXIDATIVE STRESS AND CONTRIBUTES TO THE EMERGENCE OF HEPATOCELLULAR CARCINOMA (HCC). WE PREVIOUSLY REPORTED THAT TUMOR SUPPRESSOR GENE (TSG) METHYLATION IS A CRITICAL FACTOR DURING THE EARLY STAGES OF HEPATOCARCINOGENESIS. IN THIS STUDY, WE CLARIFY THE ASSOCIATION BETWEEN OXIDATIVE STRESS AND EPIGENETIC ALTERATIONS DURING HEPATOCARCINOGENESIS. WE EXAMINED DNA OXIDATION AND METHYLATION PROFILES IN 128 LIVER BIOPSY SAMPLES FROM CHC PATIENTS. THE DNA OXIDATION AND METHYLATED TSG NUMBERS WERE QUANTIFIED USING IMMUNOHISTOCHEMICAL ANALYSIS OF 8-HYDROXYDEOXYGUANOSINE (8-OHDG) AND QUANTITATIVE PCR FOR 11 TSGS, RESPECTIVELY. THE QUANTITATIVE CHROMATIN IMMUNOPRECIPITATION-PCR (CHIP-QPCR) ASSAY IN HEPG2 AND FETAL LIVER HC CELLS TREATED WITH H2O2 WAS USED TO QUANTIFY TRIMETHYL-H3K4, ACETYLATED-H4K16 (AN ACTIVE CHROMATIN MARKER), TRIMETHYL-H3K27 (A REPRESSIVE CHROMATIN MARKER) AND 8-OHDG. WE ANALYZED 30 PROMOTERS OF 25 DIFFERENT TSGS BY QPCR. THE HIGH LEVELS OF 8-OHDG WAS THE ONLY VARIABLE THAT WAS SIGNIFICANTLY ASSOCIATED WITH THE INCREASED NUMBER OF METHYLATED TSGS IN CHC (P < 0.0001). THE CHIP-QPCR REVEALED THAT AFTER H2O2 TREATMENT OF THE CELL LINES, THE 8-OHDG-BOUND PROMOTERS SHOWED A MODIFICATION FROM AN ACTIVE CHROMATIN (TRIMETHYL-H3K4 AND ACETYLATED-H4K16 DOMINANT) TO A REPRESSIVE CHROMATIN (TRIMETHYL-H3K27 DOMINANT) STATUS. WE CONCLUDE THAT OXIDATIVE STRESS ALTERS THE CHROMATIN STATUS, WHICH LEADS TO ABNORMAL METHYLATION OF TSGS, AND CONTRIBUTES TO HEPATOCARCINOGENESIS IN CHC PATIENTS. 2013 15 1848 35 EFFECTS OF VENLAFAXINE ON THE EXPRESSION LEVEL AND METHYLATION STATUS OF GENES INVOLVED IN OXIDATIVE STRESS IN RATS EXPOSED TO A CHRONIC MILD STRESS. RECENT HUMAN AND ANIMAL STUDIES INDICATE THAT OXIDATIVE AND NITROSATIVE STRESS MAY PLAY A ROLE IN THE AETIOLOGY AND PATHOGENESIS OF DEPRESSION. THIS STUDY INVESTIGATES THE EFFECT OF CHRONIC ADMINISTRATION OF THE SEROTONIN-NOREPINEPHRINE REUPTAKE INHIBITOR, VENLAFAXINE, ON THE EXPRESSION AND METHYLATION STATUS OF SOD1, SOD2, GPX1, GPX4, CAT, NOS1 AND NOS2 IN THE BRAIN AND BLOOD OF RATS EXPOSED TO A CHRONIC MILD STRESS (CMS) MODEL OF DEPRESSION. SEPARATE GROUPS OF ANIMALS WERE EXPOSED TO CMS FOR 2 OR 7 WEEKS; THE SECOND GROUP RECEIVED SALINE OR VENLAFAXINE (10 MG/KG/D, IP) FOR 5 WEEKS. AFTER COMPLETION OF BOTH STRESS CONDITIONS AND DRUG ADMINISTRATION, THE MRNA AND PROTEIN EXPRESSION OF SELECTED GENES AND THE METHYLATION STATUS OF THEIR PROMOTERS WERE MEASURED IN PERIPHERAL MONONUCLEAR BLOOD CELLS (PBMCS) AND IN BRAIN STRUCTURES (HIPPOCAMPUS, AMYGDALA, HYPOTHALAMUS, MIDBRAIN, CORTEX, BASAL GANGLIA) WITH THE USE OF TAQMAN GENE EXPRESSION ASSAY, WESTERN BLOT AND METHYLATION-SENSITIVE HIGH-RESOLUTION MELTING TECHNIQUES. CMS CAUSED A DECREASE IN SUCROSE CONSUMPTION, AND THIS EFFECT WAS NORMALIZED BY FLUOXETINE. IN PBMCS, SOD1, SOD2 AND NOS2 MRNA EXPRESSION CHANGED ONLY AFTER VENLAFAXINE ADMINISTRATION. IN BRAIN, CAT, GPX1, GPX4 AND NOS1 GENE EXPRESSION CHANGED FOLLOWING CMS OR VENLAFAXINE EXPOSURE, MOST PROMINENTLY IN THE HIPPOCAMPUS, MIDBRAIN AND BASAL GANGLIA. CMS INCREASED THE METHYLATION OF THE GPX1 PROMOTER IN PBMCS, THE SECOND GPX4 PROMOTER IN MIDBRAIN AND BASAL GANGLIA, AND SOD1 AND SOD2 IN HIPPOCAMPUS. THE CMS ANIMALS TREATED WITH VENLAFAXINE DISPLAYED A SIGNIFICANTLY HIGHER CAT LEVEL IN MIDBRAIN AND CEREBRAL CORTEX. CMS CAUSED AN ELEVATION OF GPX4 IN THE HIPPOCAMPUS, WHICH WAS LOWERED IN CEREBRAL CORTEX BY VENLAFAXINE. THE RESULTS INDICATE THAT CMS AND VENLAFAXINE ADMINISTRATION AFFECT THE METHYLATION OF PROMOTERS OF GENES INVOLVED IN OXIDATIVE AND NITROSATIVE STRESS. THEY ALSO INDICATE THAT PERIPHERAL AND CENTRAL TISSUE DIFFER IN THEIR RESPONSE TO STRESS OR ANTIDEPRESSANT TREATMENTS. IT IS POSSIBLE THAT THAT APART FROM DNA METHYLATION, A CRUCIAL ROLE OF EXPRESSION LEVEL OF GENES MAY BE PLAYED BY OTHER FORMS OF EPIGENETIC REGULATION, SUCH AS HISTONE MODIFICATION OR MICRORNA INTERFERENCE. THESE FINDINGS PROVIDE STRONG EVIDENCE FOR THESIS THAT ANALYSIS OF THE LEVEL OF MRNA AND PROTEIN EXPRESSION AS WELL AS THE STATUS OF PROMOTER METHYLATION CAN HELP IN UNDERSTANDING THE PATHOMECHANISMS OF MENTAL DISEASES, INCLUDING DEPRESSION, AND THE MECHANISMS OF ACTION OF DRUGS EFFECTIVE IN THEIR THERAPY. 2020 16 2892 30 GARDENIAE FRUCTUS ATTENUATES THIOACETAMIDE-INDUCED LIVER FIBROSIS IN MICE VIA BOTH AMPK/SIRT1/NF-KAPPAB PATHWAY AND NRF2 SIGNALING. LIVER FIBROSIS, WHICH MEANS A SORT OF THE EXCESSIVE ACCUMULATION OF EXTRACELLULAR MATRICES (ECMS) COMPONENTS THROUGH THE LIVER TISSUE, IS CONSIDERED AS TISSUE REPAIR OR WOUND-HEALING STATUS. THIS PATHOLOGICAL STAGE POTENTIALLY LEADS TO CIRRHOSIS, IF NOT CONTROLLED, IT PROGRESSIVELY RESULTS IN HEPATOCELLULAR CARCINOMA. HEREIN, WE INVESTIGATED THE PHARMACOLOGICAL PROPERTIES AND UNDERLYING MECHANISMS OF GARDENIAE FRUCTUS (GF) AGAINST THIOACETAMIDE (TAA)-INDUCED LIVER FIBROSIS OF MICE MODEL. GF NOT ONLY ATTENUATED HEPATIC TISSUE OXIDATION BUT ALSO IMPROVED HEPATIC INFLAMMATION. WE FURTHER CONFIRMED THAT GF LED TO AMELIORATING LIVER FIBROSIS BY ECMS DEGRADATIONS. REGARDING THE POSSIBLE UNDERLYING MECHANISM OF GF, WE OBSERVED GF REGULATED EPIGENETIC REGULATOR, SIRTUIN 1 (SIRT1), IN TAA-INJECTED LIVER TISSUE. THESE ALTERATIONS WERE WELL SUPPORTED BY SIRT1 RELATED SIGNALING PATHWAYS THROUGH REGULATIONS OF ITS DOWNSTREAM PROTEINS INCLUDING, AMP-ACTIVATED PROTEIN KINASE (AMPK), P47(PHOX), NADPH OXIDASE 2, NUCLEAR FACTOR ERYTHROID 2-RELATED FACTOR 2 (NRF2), AND HEME OXYGENASE-1, RESPECTIVELY. TO VALIDATE THE POSSIBLE MECHANISM OF GF, WE USED HEPG2 CELLS WITH HYDROGEN PEROXIDE TREATED OXIDATIVE STRESS AND CHRONIC EXPOSURE CONDITIONS VIA DETERIORATIONS OF CELLULAR SIRT1. MOREOVER, GF REMARKABLY ATTENUATED ECMS ACCUMULATIONS IN TRANSFORMING GROWTH FACTOR-BETA1-INDUCED LX-2 CELLS RELYING ON THE SIRT1 EXISTENCE. TAKEN TOGETHER, GF ATTENUATED LIVER FIBROSIS THROUGH AMPK/SIRT1 PATHWAY AS WELL AS NRF2 SIGNALING CASCADES. THEREFORE, GF COULD BE A CLINICAL REMEDY FOR LIVER FIBROSIS PATIENTS IN THE FUTURE. 2021 17 6166 30 THE GLUTATHIONE SYSTEM: A NEW DRUG TARGET IN NEUROIMMUNE DISORDERS. GLUTATHIONE (GSH) HAS A CRUCIAL ROLE IN CELLULAR SIGNALING AND ANTIOXIDANT DEFENSES EITHER BY REACTING DIRECTLY WITH REACTIVE OXYGEN OR NITROGEN SPECIES OR BY ACTING AS AN ESSENTIAL COFACTOR FOR GSH S-TRANSFERASES AND GLUTATHIONE PEROXIDASES. GSH ACTING IN CONCERT WITH ITS DEPENDENT ENZYMES, KNOWN AS THE GLUTATHIONE SYSTEM, IS RESPONSIBLE FOR THE DETOXIFICATION OF REACTIVE OXYGEN AND NITROGEN SPECIES (ROS/RNS) AND ELECTROPHILES PRODUCED BY XENOBIOTICS. ADEQUATE LEVELS OF GSH ARE ESSENTIAL FOR THE OPTIMAL FUNCTIONING OF THE IMMUNE SYSTEM IN GENERAL AND T CELL ACTIVATION AND DIFFERENTIATION IN PARTICULAR. GSH IS A UBIQUITOUS REGULATOR OF THE CELL CYCLE PER SE. GSH ALSO HAS CRUCIAL FUNCTIONS IN THE BRAIN AS AN ANTIOXIDANT, NEUROMODULATOR, NEUROTRANSMITTER, AND ENABLER OF NEURON SURVIVAL. DEPLETION OF GSH LEADS TO EXACERBATION OF DAMAGE BY OXIDATIVE AND NITROSATIVE STRESS; HYPERNITROSYLATION; INCREASED LEVELS OF PROINFLAMMATORY MEDIATORS AND INFLAMMATORY POTENTIAL; DYSFUNCTIONS OF INTRACELLULAR SIGNALING NETWORKS, E.G., P53, NUCLEAR FACTOR-KAPPAB, AND JANUS KINASES; DECREASED CELL PROLIFERATION AND DNA SYNTHESIS; INACTIVATION OF COMPLEX I OF THE ELECTRON TRANSPORT CHAIN; ACTIVATION OF CYTOCHROME C AND THE APOPTOTIC MACHINERY; BLOCKADE OF THE METHIONINE CYCLE; AND COMPROMISED EPIGENETIC REGULATION OF GENE EXPRESSION. AS SUCH, GSH DEPLETION HAS MARKED CONSEQUENCES FOR THE HOMEOSTATIC CONTROL OF THE IMMUNE SYSTEM, OXIDATIVE AND NITROSATIVE STRESS (O&NS) PATHWAYS, REGULATION OF ENERGY PRODUCTION, AND MITOCHONDRIAL SURVIVAL AS WELL. GSH DEPLETION AND CONCOMITANT INCREASE IN O&NS AND MITOCHONDRIAL DYSFUNCTIONS PLAY A ROLE IN THE PATHOPHYSIOLOGY OF DIVERSE NEUROIMMUNE DISORDERS, INCLUDING DEPRESSION, MYALGIC ENCEPHALOMYELITIS/CHRONIC FATIGUE SYNDROME AND PARKINSON'S DISEASE, SUGGESTING THAT DEPLETED GSH IS AN INTEGRAL PART OF THESE DISEASES. THERAPEUTICAL INTERVENTIONS THAT AIM TO INCREASE GSH CONCENTRATIONS IN VIVO INCLUDE N-ACETYL CYSTEINE; NRF-2 ACTIVATION VIA HYPERBARIC OXYGEN THERAPY; DIMETHYL FUMARATE; PHYTOCHEMICALS, INCLUDING CURCUMIN, RESVERATROL, AND CINNAMON; AND FOLATE SUPPLEMENTATION. 2014 18 903 31 CHRONIC EXPOSURE TO BISPHENOL A RESULTED IN ALTERATIONS OF REPRODUCTIVE FUNCTIONS VIA IMMUNE DEFENSE, OXIDATIVE DAMAGE AND DISRUPTION DNA/HISTONE METHYLATION IN MALE RARE MINNOW GOBIOCYPRIS RARUS. BISPHENOL A (BPA) IS A WIDELY USED CHEMICAL THAT REPRESENTS A REPRODUCTIVE HAZARD IN FISH. HOWEVER, THE MOLECULAR PATHWAYS MEDIATING REPRODUCTIVE TOXICITY UNDER CHRONIC BPA EXPOSURE REMAIN UNCLEAR. TO STUDY THE REPRODUCTIVE HAZARDS ASSOCIATED WITH CHRONIC BPA EXPOSURE, ADULT MALE RARE MINNOWS (GOBIOCYPRIS RARUS) WERE TREATED WITH 15 MUG L (-) (1) AND 225 MUG L (-) (1) BPA FOR 90 DAYS. RESULTS SHOWED THAT CHRONIC BPA TREATMENT INDUCED REPRODUCTIVE IMPAIRMENTS WITH DECREASED FERTILIZATION CAPACITY AND MOVEMENT TIME OF SPERM. TRANSCRIPTOME ANALYSIS INDICATED 1421 TRANSCRIPTS THAT WERE DIFFERENTIALLY EXPRESSED IN RESPONSE TO BPA EXPOSURE, WHICH ARE INVOLVED IN THE BIOLOGICAL PROCESS OF OXIDATIVE STRESS, IMMUNE RESPONSES AND DNA/HISTONE METHYLATION. BPA CAUSED THE OXIDATIVE STRESS VIA SIGNIFICANTLY INCREASING HYDROGEN PEROXIDE (H(2)O(2)) LEVELS AND INHIBITING THE ACTIVITIES OF ANTIOXIDANT-RELATED ENZYMES (CATALASE, CAT). BPA CAUSED AN INFLAMMATORY RESPONSE IN THE TESTES BY SIGNIFICANTLY INCREASING IL-1BETA LEVELS AND INDUCING INFILTRATION OF INFLAMMATORY CELLS. MOREOVER, EXPOSURE TO 15 MUG L (-) (1) BPA SIGNIFICANTLY DECREASED THE GENOMIC DNA METHYLATION LEVEL. THESE DATA REVEALED THAT CHRONIC BPA EXPOSURE HAD ADVERSE EFFECTS ON MALE REPRODUCTION. OXIDATIVE STRESS, INFLAMMATORY RESPONSE AND DNA/HISTONE METHYLATION MIGHT ACCOUNT FOR THE DECREASED SPERM QUALITY. 2021 19 2278 30 EPIGENETIC REGULATION BY SUV4-20H1 IN CARDIOPULMONARY PROGENITOR CELLS IS REQUIRED TO PREVENT PULMONARY HYPERTENSION AND CHRONIC OBSTRUCTIVE PULMONARY DISEASE. BACKGROUND: THE PATHOGENESIS OF LIFE-THREATENING CARDIOPULMONARY DISEASES SUCH AS PULMONARY HYPERTENSION (PH) AND CHRONIC OBSTRUCTIVE PULMONARY DISEASE (COPD) ORIGINATES FROM A COMPLEX INTERPLAY OF ENVIRONMENTAL FACTORS AND GENETIC PREDISPOSITIONS THAT IS NOT FULLY UNDERSTOOD. LIKEWISE, LITTLE IS KNOWN ABOUT DEVELOPMENTAL ABNORMALITIES OR EPIGENETIC DYSREGULATIONS THAT MIGHT PREDISPOSE FOR PH OR COPD IN ADULT INDIVIDUALS. METHODS: TO IDENTIFY PATHOLOGY-ASSOCIATED EPIGENETIC ALTERATION IN DISEASED LUNG TISSUES, WE SCREENED A COHORT OF HUMAN PATIENTS WITH PH AND COPD FOR CHANGES OF HISTONE MODIFICATIONS BY IMMUNOFLUORESCENCE STAINING. TO ANALYZE THE FUNCTION OF H4K20ME2/3 IN LUNG PATHOGENESIS, WE DEVELOPED A SERIES OF SUV4-20H1 KNOCKOUT MOUSE LINES TARGETING CARDIOPULMONARY PROGENITOR CELLS AND DIFFERENT HEART AND LUNG CELL TYPES, FOLLOWED BY HEMODYNAMIC STUDIES AND MORPHOMETRIC ASSESSMENT OF TISSUE SAMPLES. MOLECULAR, CELLULAR, AND BIOCHEMICAL TECHNIQUES WERE APPLIED TO ANALYZE THE FUNCTION OF SUV4-20H1-DEPENDENT EPIGENETIC PROCESSES IN CARDIOPULMONARY PROGENITOR CELLS AND THEIR DERIVATIVES. RESULTS: WE DISCOVERED A STRONG REDUCTION OF THE HISTONE MODIFICATIONS OF H4K20ME2/3 IN HUMAN PATIENTS WITH COPD BUT NOT PATIENTS WITH PH THAT DEPEND ON THE ACTIVITY OF THE H4K20 DI-METHYLTRANSFERASE SUV4-20H1. LOSS OF SUV4-20H1 IN CARDIOPULMONARY PROGENITOR CELLS CAUSED A COPD-LIKE/PH PHENOTYPE IN MICE INCLUDING THE FORMATION OF PERIVASCULAR TERTIARY LYMPHOID TISSUE AND GOBLET CELL HYPERPLASIA, HYPERPROLIFERATION OF SMOOTH MUSCLE CELLS/MYOFIBROBLASTS, IMPAIRED ALVEOLARIZATION AND MATURATION DEFECTS OF THE MICROVASCULATURE LEADING TO MASSIVE RIGHT VENTRICULAR DILATATION AND PREMATURE DEATH. MECHANISTICALLY, SUV4-20H1 BINDS DIRECTLY TO THE 5'-UPSTREAM REGULATORY ELEMENT OF THE SUPEROXIDE DISMUTASE 3 (SOD3) GENE TO REPRESS ITS EXPRESSION. INCREASED LEVELS OF THE EXTRACELLULAR SOD3 ENZYME IN SUV4-20H1 MUTANTS INCREASES HYDROGEN PEROXIDE CONCENTRATIONS, CAUSING VASCULAR DEFECTS AND IMPAIRING ALVEOLARIZATION. CONCLUSIONS: OUR FINDINGS REVEAL A PIVOTAL ROLE OF THE HISTONE MODIFIER SUV4-20H1 IN CARDIOPULMONARY CODEVELOPMENT AND UNCOVER THE DEVELOPMENTAL ORIGINS OF CARDIOPULMONARY DISEASES. WE ASSUME THAT THE STUDY WILL FACILITATE THE UNDERSTANDING OF PATHOGENIC EVENTS CAUSING PH AND COPD AND AID THE DEVELOPMENT OF EPIGENETIC DRUGS FOR THE TREATMENT OF CARDIOPULMONARY DISEASES. 2021 20 978 36 CHRONIC OXIDATIVE STRESS CAUSES ESTROGEN-INDEPENDENT AGGRESSIVE PHENOTYPE, AND EPIGENETIC INACTIVATION OF ESTROGEN RECEPTOR ALPHA IN MCF-7 BREAST CANCER CELLS. THE ROLE OF CHRONIC OXIDATIVE STRESS IN THE DEVELOPMENT AND AGGRESSIVE GROWTH OF ESTROGEN RECEPTOR (ER)-POSITIVE BREAST CANCER IS WELL KNOWN; HOWEVER, THE MECHANISTIC UNDERSTANDING IS NOT CLEAR. ESTROGEN-INDEPENDENT GROWTH IS ONE OF THE FEATURES OF AGGRESSIVE SUBTYPE OF BREAST CANCER. THEREFORE, THE OBJECTIVE OF THIS STUDY WAS TO EVALUATE THE EFFECT OF OXIDATIVE STRESS ON ESTROGEN SENSITIVITY AND EXPRESSION OF NUCLEAR ESTROGEN RECEPTORS IN ER-POSITIVE BREAST CANCER CELLS. MCF-7 CELLS CHRONICALLY EXPOSED TO HYDROGEN PEROXIDE WERE USED AS A CELL MODEL IN THIS STUDY, AND THEIR GROWTH IN RESPONSE TO 17-BETA ESTRADIOL WAS EVALUATED BY CELL VIABILITY, CELL CYCLE, AND CELL MIGRATION ANALYSIS. RESULTS WERE FURTHER CONFIRMED AT MOLECULAR LEVEL BY ANALYSIS OF GENE EXPRESSIONS AT TRANSCRIPT AND PROTEIN LEVELS. HISTONE H3 MODIFICATIONS, EXPRESSION OF EPIGENETIC REGULATORY GENES, AND THE EFFECT OF DNA DEMETHYLATION WERE ALSO ANALYZED. LOSS OF GROWTH IN RESPONSE TO ESTROGEN WITH A DECREASE IN ERALPHA EXPRESSION WAS OBSERVED IN MCF-7 CELLS ADAPTED TO CHRONIC OXIDATIVE STRESS. INCREASES IN MTTFA AND NRF1 IN THESE CELLS FURTHER SUGGESTED THE ROLE OF MITOCHONDRIA-DEPENDENT REDOX-SENSITIVE GROWTH SIGNALING AS AN ALTERNATIVE PATHWAY TO ESTROGEN-DEPENDENT GROWTH. CHANGES IN EXPRESSION OF EPIGENETIC REGULATORY GENES, LEVELS OF HISTONE H3 MODIFICATIONS AS WELL AS SIGNIFICANT RESTORATIONS OF BOTH ERALPHA EXPRESSION AND ESTROGEN RESPONSE BY 5-AZA-2'-DEOXYCYTIDINE FURTHER CONFIRMED THE EPIGENETIC BASIS FOR ESTROGEN-INDEPENDENT GROWTH IN THESE CELLS. IN CONCLUSION, RESULTS OF THIS STUDY SUGGEST THAT CHRONIC OXIDATIVE STRESS CAN CONVERT ESTROGEN-DEPENDENT NONAGGRESSIVE BREAST CANCER CELLS INTO ESTROGEN-INDEPENDENT AGGRESSIVE FORM POTENTIALLY BY EPIGENETIC MECHANISM. 2015