1 294 82 AGING INCREASES VULNERABILITY TO STRESS-INDUCED DEPRESSION VIA UPREGULATION OF NADPH OXIDASE IN MICE. BRAIN AGING PROCEEDS WITH CELLULAR AND MOLECULAR CHANGES IN THE LIMBIC SYSTEM. AGING-DEPENDENT CHANGES MIGHT AFFECT EMOTION AND STRESS COPING, YET THE UNDERLYING MECHANISMS REMAIN UNCLEAR. HERE, WE SHOW AGED (18-MONTH-OLD) MICE EXHIBIT UPREGULATION OF NADPH OXIDASE AND OXIDATIVE STRESS IN THE HIPPOCAMPUS, WHICH MIRRORS THE CHANGES IN YOUNG (2-MONTH-OLD) MICE SUBJECTED TO CHRONIC STRESS. AGED MICE THAT LACK P47PHOX, A KEY SUBUNIT OF NADPH OXIDASE, DO NOT SHOW INCREASED OXIDATIVE STRESS. AGED MICE EXHIBIT DEPRESSION-LIKE BEHAVIOR FOLLOWING WEAK STRESS THAT DOES NOT PRODUCE DEPRESSIVE BEHAVIOR IN YOUNG MICE. AGED MICE HAVE REDUCED EXPRESSION OF THE EPIGENETIC FACTOR SUV39H1 AND ITS UPSTREAM REGULATOR P-AMPK, AND INCREASED EXPRESSION OF PPP2CA IN THE HIPPOCAMPUS-CHANGES THAT OCCUR IN YOUNG MICE EXPOSED TO CHRONIC STRESS. SUV39H1 MEDIATES STRESS- AND AGING-INDUCED SUSTAINED UPREGULATION OF P47PHOX AND OXIDATIVE STRESS. THESE RESULTS SUGGEST THAT AGING INCREASES SUSCEPTIBILITY TO STRESS BY UPREGULATING NADPH OXIDASE IN THE HIPPOCAMPUS. 2020 2 2181 21 EPIGENETIC MECHANISMS REGULATE NADPH OXIDASE-4 EXPRESSION IN CELLULAR SENESCENCE. AGING IS A WELL-KNOWN RISK FACTOR FOR A LARGE NUMBER OF CHRONIC DISEASES, INCLUDING THOSE OF THE LUNG. CELLULAR SENESCENCE IS ONE OF THE HALLMARKS OF AGING, AND CONTRIBUTES TO THE PATHOGENESIS OF AGE-RELATED DISEASES. RECENT STUDIES IMPLICATE THE REACTIVE OXYGEN SPECIES (ROS)-GENERATING ENZYME, NADPH OXIDASE 4 (NOX4) IN CELLULAR SENESCENCE. IN THIS STUDY, WE INVESTIGATED POTENTIAL MECHANISMS FOR EPIGENETIC REGULATION OF NOX4. WE OBSERVED CONSTITUTIVELY HIGH LEVELS OF NOX4 GENE/PROTEIN AND ACTIVITY IN A MODEL OF REPLICATION-INDUCED CELLULAR SENESCENCE OF LUNG FIBROBLASTS. IN REPLICATIVE SENESCENT FIBROBLASTS, THE NOX4 GENE IS ENRICHED WITH THE ACTIVATION HISTONE MARK, H4K16AC, AND INVERSELY ASSOCIATED WITH THE REPRESSIVE HISTONE MARK, H4K20ME3, SUPPORTING AN ACTIVE TRANSCRIPTIONAL CHROMATIN CONFORMATION. SILENCING OF THE HISTONE ACETYLTRANSFERASE MOF, WHICH SPECIFICALLY ACETYLATES H4K16, DOWN-REGULATES NOX4 GENE/PROTEIN EXPRESSION. THE NOX4 GENE PROMOTER IS RICH IN CPG SITES; MIXED COPIES OF METHYLATED AND UNMETHYLATED NOX4 DNA WERE DETECTED IN BOTH NONSENESCENT AND SENESCENT CELLS. INTERESTINGLY, THE NOX4 GENE IS VARIABLY ASSOCIATED WITH SPECIFIC DNA METHYLTRANSFERASES AND METHYL BINDING PROTEINS IN THESE TWO CELL POPULATIONS. THESE RESULTS INDICATE A CRITICAL ROLE FOR HISTONE MODIFICATIONS INVOLVING H4K16AC IN EPIGENETIC ACTIVATION OF THE NOX4 GENE, WHILE THE ROLE OF DNA METHYLATION MAY BE CONTEXTUAL. DEFINING MECHANISMS FOR THE EPIGENETIC REGULATION OF NOX4 WILL AID IN THE DEVELOPMENT OF NOVEL THERAPEUTIC STRATEGIES FOR AGE-RELATED DISEASES IN WHICH THIS GENE IS OVEREXPRESSED, IN PARTICULAR IDIOPATHIC PULMONARY FIBROSIS AND CANCER. 2015 3 449 28 APOCYNIN PREVENTS ANXIETY-LIKE BEHAVIOR AND HISTONE DEACETYLASES OVEREXPRESSION INDUCED BY SUB-CHRONIC STRESS IN MICE. ANXIETY DISORDERS ARE COMMON MENTAL HEALTH DISEASES AFFECTING UP TO 7% OF PEOPLE AROUND THE WORLD. STRESS IS CONSIDERED ONE OF THE MAJOR ENVIRONMENTAL RISK FACTORS TO PROMOTE ANXIETY DISORDERS THROUGH MECHANISMS INVOLVING EPIGENETIC CHANGES. MOREOVER, ALTERATION IN REDOX BALANCE AND INCREASED REACTIVE OXYGEN SPECIES (ROS) PRODUCTION HAVE BEEN DETECTED IN ANXIETY PATIENTS AND IN STRESSED-ANIMAL MODELS OF ANXIETY. HERE WE TESTED IF THE ADMINISTRATION OF APOCYNIN, A NATURAL ORIGIN ANTIOXIDANT, MAY PREVENT THE ANXIETY-LIKE PHENOTYPE AND REDUCTION OF HISTONE ACETYLATION INDUCED BY A SUBCHRONIC FORCED SWIMMING STRESS (FSS) PARADIGM. WE FOUND THAT APOCYNIN PREVENTED THE ENHANCED LATENCY TIME IN THE NOVELTY-SUPPRESSED FEEDING TEST, AND THE PRODUCTION OF MALONDIALDEHYDE INDUCED BY FSS. MOREOVER, APOCYNIN WAS ABLE TO BLOCK THE UPREGULATION OF P47PHOX, A KEY SUBUNIT OF THE NADPH OXIDASE COMPLEX. FINALLY, APOCYNIN PREVENTED THE RISE OF HIPPOCAMPAL HDAC1, HDAC4 AND HDAC5, AND THE REDUCTION OF HISTONE-3 ACETYLATION LEVELS PROMOTED BY FSS EXPOSURE. IN CONCLUSION, OUR RESULTS PROVIDE EVIDENCE THAT APOCYNIN REDUCES THE DELETERIOUS EFFECT OF STRESS AND SUGGESTS THAT OXIDATIVE STRESS MAY REGULATE EPIGENETIC MECHANISMS. 2021 4 199 20 ACTIVATED HISTONE ACETYLTRANSFERASE P300/CBP-RELATED SIGNALLING PATHWAYS MEDIATE UP-REGULATION OF NADPH OXIDASE, INFLAMMATION, AND FIBROSIS IN DIABETIC KIDNEY. ACCUMULATING EVIDENCE IMPLICATES THE HISTONE ACETYLATION-BASED EPIGENETIC MECHANISMS IN THE PATHOETIOLOGY OF DIABETES-ASSOCIATED MICRO-/MACROVASCULAR COMPLICATIONS. DIABETIC KIDNEY DISEASE (DKD) IS A PROGRESSIVE CHRONIC INFLAMMATORY MICROVASCULAR DISORDER ULTIMATELY LEADING TO GLOMERULOSCLEROSIS AND KIDNEY FAILURE. WE HYPOTHESIZED THAT HISTONE ACETYLTRANSFERASE P300/CBP MAY BE INVOLVED IN MEDIATING DIABETES-ACCELERATED RENAL DAMAGE. IN THIS STUDY, WE AIMED AT INVESTIGATING THE POTENTIAL ROLE OF P300/CBP IN THE UP-REGULATION OF RENAL NADPH OXIDASE (NOX), REACTIVE OXYGEN SPECIES (ROS) PRODUCTION, INFLAMMATION, AND FIBROSIS IN DIABETIC MICE. DIABETIC C57BL/6J MICE WERE RANDOMIZED TO RECEIVE 10 MG/KG C646, A SELECTIVE P300/CBP INHIBITOR, OR ITS VEHICLE FOR 4 WEEKS. WE FOUND THAT IN THE KIDNEY OF C646-TREATED DIABETIC MICE, THE LEVEL OF H3K27AC, AN EPIGENETIC MARK OF ACTIVE GENE EXPRESSION, WAS SIGNIFICANTLY REDUCED. PHARMACOLOGICAL INHIBITION OF P300/CBP SIGNIFICANTLY DOWN-REGULATED THE DIABETES-INDUCED ENHANCED EXPRESSION OF NOX SUBTYPES, PRO-INFLAMMATORY, AND PRO-FIBROTIC MOLECULES IN THE KIDNEY OF MICE, AND THE GLOMERULAR ROS OVERPRODUCTION. OUR STUDY PROVIDES EVIDENCE THAT THE ACTIVATION OF P300/CBP ENHANCES ROS PRODUCTION, POTENTIALLY GENERATED BY UP-REGULATED NOX, INFLAMMATION, AND THE PRODUCTION OF EXTRACELLULAR MATRIX PROTEINS IN THE DIABETIC KIDNEY. THE DATA SUGGEST THAT P300/CBP-PHARMACOLOGICAL INHIBITORS MAY BE ATTRACTIVE TOOLS TO MODULATE DIABETES-ASSOCIATED PATHOLOGICAL PROCESSES TO EFFICIENTLY REDUCE THE BURDEN OF DKD. 2021 5 4890 25 OXIDATIVE STRESS AND HEPATIC NOX PROTEINS IN CHRONIC HEPATITIS C AND HEPATOCELLULAR CARCINOMA. HEPATOCELLULAR CARCINOMA (HCC) IS THE MOST COMMON LIVER CANCER AND A LEADING CAUSE OF CANCER-RELATED MORTALITY IN THE WORLD. HEPATITIS C VIRUS (HCV) IS A MAJOR ETIOLOGIC AGENT OF HCC. A MAJORITY OF HCV INFECTIONS LEAD TO CHRONIC INFECTION THAT CAN PROGRESS TO CIRRHOSIS AND, EVENTUALLY, HCC AND LIVER FAILURE. A COMMON PATHOGENIC FEATURE PRESENT IN HCV INFECTION, AND OTHER CONDITIONS LEADING TO HCC, IS OXIDATIVE STRESS. HCV DIRECTLY INCREASES SUPEROXIDE AND H2O2 FORMATION IN HEPATOCYTES BY ELEVATING NOX PROTEIN EXPRESSION AND SENSITIZING MITOCHONDRIA TO REACTIVE OXYGEN SPECIES GENERATION WHILE DECREASING GLUTATHIONE. NITRIC OXIDE SYNTHESIS AND HEPATIC IRON ARE ALSO ELEVATED. FURTHERMORE, ACTIVATION OF PHAGOCYTIC NADPH OXIDASE (NOX) 2 OF HOST IMMUNE CELLS IS LIKELY TO EXACERBATE OXIDATIVE STRESS IN HCV-INFECTED PATIENTS. KEY MECHANISMS OF HCC INCLUDE GENOME INSTABILITY, EPIGENETIC REGULATION, INFLAMMATION WITH CHRONIC TISSUE INJURY AND SUSTAINED CELL PROLIFERATION, AND MODULATION OF CELL GROWTH AND DEATH. OXIDATIVE STRESS, OR NOX PROTEINS, PLAYS VARIOUS ROLES IN THESE MECHANISMS. NOX PROTEINS ALSO FUNCTION IN HEPATIC FIBROSIS, WHICH COMMONLY PRECEDES HCC, AND NOX4 ELEVATION BY HCV IS MEDIATED BY TRANSFORMING GROWTH FACTOR BETA. THIS REVIEW SUMMARIZES MECHANISMS OF ONCOGENESIS BY HCV, HIGHLIGHTING THE ROLES OF OXIDATIVE STRESS AND HEPATIC NOX ENZYMES IN HCC. 2014 6 2950 14 GENETIC AND EPIGENETIC DAMAGE INDUCED BY REACTIVE NITROGEN SPECIES: IMPLICATIONS IN CARCINOGENESIS. CHRONIC INFECTION AND INFLAMMATION ARE RECOGNIZED RISK FACTORS FOR HUMAN CANCER AT VARIOUS SITES. INFECTION AND INFLAMMATION CAN ACTIVATE AND INDUCE A VARIETY OF OXIDANT-GENERATING ENZYMES, INCLUDING NADPH OXIDASE AND INDUCIBLE NITRIC OXIDE SYNTHASE. REACTIVE OXYGEN AND NITROGEN SPECIES PRODUCED BY SUCH ENZYMES REACT WITH EACH OTHER TO GENERATE NEW AND MORE POTENT REACTIVE SPECIES. THESE OXIDANTS NOT ONLY CAN DAMAGE DNA AND INDUCE MUTATIONS, BUT ALSO CAN ACTIVATE ONCOGENE PRODUCTS AND/OR INACTIVATE TUMOR-SUPPRESSOR PROTEINS, THUS CONTRIBUTING TO MOST PROCESSES OF CARCINOGENESIS. APPROPRIATE TREATMENT OF INFLAMMATION SHOULD BE FURTHER EXPLORED FOR CHEMOPREVENTION OF HUMAN CANCERS, ESPECIALLY THOSE ASSOCIATED WITH CHRONIC INFLAMMATION. 2003 7 5860 27 SULFORAPHANE PREVENTS ANGIOTENSIN II-INDUCED CARDIOMYOPATHY BY ACTIVATION OF NRF2 THROUGH EPIGENETIC MODIFICATION. NUCLEAR FACTOR ERYTHROID 2-RELATED FACTOR (NRF2) IS AN IMPORTANT REGULATOR OF CELLULAR ANTIOXIDANT DEFENCE. WE PREVIOUSLY SHOWED THAT SFN PREVENTED ANG II-INDUCED CARDIAC DAMAGE VIA ACTIVATION OF NRF2. HOWEVER, THE UNDERLYING MECHANISM OF SFN'S PERSISTENT CARDIAC PROTECTION REMAINS UNCLEAR. THIS STUDY AIMED TO EXPLORE THE POTENTIAL OF SFN IN ACTIVATING CARDIAC NRF2 THROUGH EPIGENETIC MECHANISMS. WILD-TYPE MICE WERE INJECTED SUBCUTANEOUSLY WITH ANG II, WITH OR WITHOUT SFN. ADMINISTRATION OF CHRONIC ANG II-INDUCED CARDIAC INFLAMMATORY FACTOR EXPRESSION, OXIDATIVE DAMAGE, FIBROSIS AND CARDIAC REMODELLING AND DYSFUNCTION, ALL OF WHICH WERE EFFECTIVELY IMPROVED BY SFN TREATMENT, COUPLED WITH AN UP-REGULATION OF NRF2 AND DOWNSTREAM GENES. BISULFITE GENOME SEQUENCING AND CHROMATIN IMMUNOPRECIPITATION (CHIP) WERE PERFORMED TO DETECT THE METHYLATION LEVEL OF THE FIRST 15 CPGS AND HISTONE H3 ACETYLATION (AC-H3) STATUS IN THE NRF2 PROMOTER REGION, RESPECTIVELY. THE RESULTS SHOWED THAT SFN REDUCED ANG II-INDUCED CPG HYPERMETHYLATION AND PROMOTED AC-H3 ACCUMULATION IN THE NRF2 PROMOTER REGION, ACCOMPANIED BY THE INHIBITION OF GLOBAL DNMT AND HDAC ACTIVITY, AND A DECREASED PROTEIN EXPRESSION OF KEY DNMT AND HDAC ENZYMES. TAKEN TOGETHER, SFN EXERTS ITS CARDIOPROTECTIVE EFFECT THROUGH EPIGENETIC MODIFICATION OF NRF2, WHICH MAY PARTIALLY CONTRIBUTE TO LONG-TERM ACTIVATION OF CARDIAC NRF2. 2021 8 6425 20 THE TRANSCRIPTION FACTOR REST UP-REGULATES TYROSINE HYDROXYLASE AND ANTIAPOPTOTIC GENES AND PROTECTS DOPAMINERGIC NEURONS AGAINST MANGANESE TOXICITY. DOPAMINERGIC FUNCTIONS ARE IMPORTANT FOR VARIOUS BIOLOGICAL ACTIVITIES, AND THEIR IMPAIRMENT LEADS TO NEURODEGENERATION, A HALLMARK OF PARKINSON'S DISEASE (PD). CHRONIC MANGANESE (MN) EXPOSURE CAUSES THE NEUROLOGICAL DISORDER MANGANISM, PRESENTING SYMPTOMS SIMILAR TO THOSE OF PD. EMERGING EVIDENCE HAS LINKED THE TRANSCRIPTION FACTOR RE1-SILENCING TRANSCRIPTION FACTOR (REST) TO PD AND ALSO ALZHEIMER'S DISEASE. BUT REST'S ROLE IN DOPAMINERGIC NEURONS IS UNCLEAR. HERE, WE INVESTIGATED WHETHER REST PROTECTS DOPAMINERGIC NEURONS AGAINST MN-INDUCED TOXICITY AND ENHANCES EXPRESSION OF THE DOPAMINE-SYNTHESIZING ENZYME TYROSINE HYDROXYLASE (TH). WE REPORT THAT REST BINDS TO RE1 CONSENSUS SITES IN THE TH GENE PROMOTER, STIMULATES TH TRANSCRIPTION, AND INCREASES TH MRNA AND PROTEIN LEVELS IN DOPAMINERGIC CELLS. REST BINDING TO THE TH PROMOTER RECRUITED THE EPIGENETIC MODIFIER CAMP-RESPONSE ELEMENT-BINDING PROTEIN-BINDING PROTEIN/P300 AND THEREBY UP-REGULATED TH EXPRESSION. REST RELIEVED MN-INDUCED REPRESSION OF TH PROMOTER ACTIVITY, MRNA, AND PROTEIN LEVELS AND ALSO REDUCED MN-INDUCED OXIDATIVE STRESS, INFLAMMATION, AND APOPTOSIS IN DOPAMINERGIC NEURONS. REST REDUCED MN-INDUCED PROINFLAMMATORY CYTOKINES, INCLUDING TUMOR NECROSIS FACTOR ALPHA, INTERLEUKIN 1BETA (IL-1BETA), IL-6, AND INTERFERON GAMMA. MOREOVER, REST INHIBITED THE MN-INDUCED PROAPOPTOTIC PROTEINS BCL-2-ASSOCIATED X PROTEIN (BAX) AND DEATH-ASSOCIATED PROTEIN 6 (DAXX) AND ATTENUATED AN MN-INDUCED DECREASE IN THE ANTIAPOPTOTIC PROTEINS BCL-2 AND BCL-XL. REST ALSO ENHANCED THE EXPRESSION OF ANTIOXIDANT PROTEINS, INCLUDING CATALASE, NF-E2-RELATED FACTOR 2 (NRF2), AND HEME OXYGENASE 1 (HO-1). OUR FINDINGS INDICATE THAT REST ACTIVATES TH EXPRESSION AND THEREBY PROTECTS NEURONS AGAINST MN-INDUCED TOXICITY AND NEUROLOGICAL DISORDERS ASSOCIATED WITH DOPAMINERGIC NEURODEGENERATION. 2020 9 1201 23 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 10 4044 14 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 11 6456 19 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 12 6166 22 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 13 5010 15 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 14 2892 28 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 15 5942 27 TARGETING OF CELLULAR REDOX METABOLISM FOR MITIGATION OF RADIATION INJURY. ACCIDENTAL EXPOSURE TO IONIZING RADIATION IS A SERIOUS CONCERN TO HUMAN LIFE. STUDIES ON THE MITIGATION OF SIDE EFFECTS FOLLOWING EXPOSURE TO ACCIDENTAL RADIATION EVENTS ARE ONGOING. RECENT STUDIES HAVE SHOWN THAT RADIATION CAN ACTIVATE SEVERAL SIGNALING PATHWAYS, LEADING TO CHANGES IN THE METABOLISM OF FREE RADICALS INCLUDING REACTIVE OXYGEN SPECIES (ROS) AND NITRIC OXIDE (NO). CELLULAR AND MOLECULAR MECHANISMS SHOW THAT RADIATION CAN CAUSE DISRUPTION OF NORMAL REDUCTION/OXIDATION (REDOX) SYSTEM. MITOCHONDRIA MALFUNCTION FOLLOWING EXPOSURE TO RADIATION AND MUTATIONS IN MITOCHONDRIA DNA (MTDNA) HAVE A KEY ROLE IN CHRONIC OXIDATIVE STRESS. FURTHERMORE, EXPOSURE TO RADIATION LEADS TO INFILTRATION OF INFLAMMATORY CELLS SUCH AS MACROPHAGES, LYMPHOCYTES AND MAST CELLS, WHICH ARE IMPORTANT SOURCES OF ROS AND NO. THESE CELLS GENERATE FREE RADICALS VIA UPREGULATION OF SOME PRO-OXIDANT ENZYMES SUCH AS NADPH OXIDASES, INDUCIBLE NITRIC OXIDE SYNTHASE (INOS) AND CYCLOOXYGENASE-2 (COX-2). EPIGENETIC CHANGES ALSO HAVE A KEY ROLE IN A SIMILAR WAY. OTHER MEDIATORS SUCH AS MAMMALIAN TARGET OF RAPAMYCIN (MTOR) AND PEROXISOME PROLIFERATOR-ACTIVATED RECEPTOR (PPAR), WHICH ARE INVOLVED IN THE NORMAL METABOLISM OF CELLS HAVE ALSO BEEN SHOWN TO REGULATE CELL DEATH FOLLOWING EXPOSURE TO RADIATION. THESE MECHANISMS ARE TISSUE SPECIFIC. INHIBITION OR ACTIVATION OF EACH OF THESE TARGETS CAN BE SUGGESTED FOR MITIGATION OF RADIATION INJURY IN A SPECIFIC TISSUE. IN THE CURRENT PAPER, WE REVIEW THE CELLULAR AND MOLECULAR CHANGES IN THE METABOLISM OF CELLS AND ROS/NO FOLLOWING EXPOSURE TO RADIATION. FURTHERMORE, THE POSSIBLE STRATEGIES FOR MITIGATION OF RADIATION INJURY THROUGH MODULATION OF CELLULAR METABOLISM IN IRRADIATED ORGANS WILL BE DISCUSSED. 2020 16 3940 23 LNCRNA DLEU2 REGULATES SIRTUINS AND MITOCHONDRIAL RESPIRATORY CHAIN COMPLEX IV: A NOVEL PATHWAY IN OBESITY AND OFFSPRING'S HEALTH. BACKGROUND: LONG NON-CODING RNAS (LNCRNAS) HAVE EMERGED AS A RAPIDLY EXPANDING AREA OF INTEREST IN CHRONIC DISEASES. THEY ARE MOSTLY UNKNOWN FOR ROLES IN METABOLIC REGULATION. SIRTUINS, AN EPIGENETIC MODULATOR CLASS, REGULATE METABOLIC PATHWAYS. HOWEVER, HOW SIRTUINS ARE REGULATED VIA LNCRNA IS UNKNOWN. WE HYPOTHESIZED THAT A HIGH-FAT HIGH-FRUCTOSE DIET (HFD-HF) DURING PREGNANCY WOULD INCREASE THE RISK FOR OBESITY VIA LNCRNA-SIRTUIN PATHWAYS. METHODS: FEMALE C57BL/6 MICE (F0) WERE FED EITHER CHOW DIET (CD) OR HFD-HF FOR 6 WEEKS TILL BIRTH. THE PUPS (F1) WERE FED EITHER CD OR HFD-HF FOR 20 WEEKS. EXPRESSION OF DLEU2, SIRTUINS, MITOCHONDRIAL RESPIRATORY COMPLEXES, AND OXIDATIVE STRESS WERE INVESTIGATED IN THE F1 LIVERS. FASTING BLOOD GLUCOSE, INSULIN SENSITIVITY, GLUCOSE TOLERANCE, BODY AND TISSUES WEIGHT WERE MEASURED. A MECHANISTIC INTERACTION WAS THEN CARRIED OUT USING A DLEU2 KNOCKDOWN EXPERIMENT IN THE HEPG2 CELL. RESULTS: DLEU2 AND SIRTUINS WERE BOTH SIGNIFICANTLY DECREASED IN THE LIVERS OF HFD-HF FED MALE F1 WHOSE MOTHERS WERE EITHER FED CD OR HFD-HF DURING REPRODUCTIVE AND PREGNANCY WINDOWS. CONFIRMING THIS CONNECTION, UPON SILENCING DLEU2, TRANSCRIPTION LEVELS OF SIRT1 THROUGH 6 AND TRANSLATIONAL LEVELS OF SIRT1, 3, 5, AND 6 WERE SIGNIFICANTLY DOWNREGULATED. KNOCKDOWN OF DLEU2 SIGNIFICANTLY DECREASED THE PROTEIN LEVEL OF CYTOCHROME-C OXIDASE (COMPLEX IV, MTCO1) WITHOUT ALTERING OTHER MITOCHONDRIAL COMPLEXES, DECREASED MITOCHONDRIAL MEMBRANE POTENTIAL, DECREASED ATP, AND INCREASED REACTIVE OXYGEN SPECIES. INTERESTINGLY, IN F1 LIVERS, THE PROTEIN LEVEL OF MTCO1 WAS ALSO SIGNIFICANTLY DECREASED UNDER AN HFD-HF DIET OR EVEN UNDER CHOW DIET IF THE MOTHER WAS EXPOSED TO HFD-HF. CONCLUSION: OUR FINDINGS REVEAL FOR THE FIRST TIME THAT ONE LNCRNA CAN REGULATE SIRTUINS AND A SPECIFIC MITOCHONDRIAL COMPLEX. FURTHERMORE, DIET OR MATERNAL DIET CAN MODULATE DLEU2 AND ITS DOWNSTREAM REGULATORS IN OFFSPRING, SUGGESTING A POTENTIAL ROLE OF DLEU2 IN METABOLIC DISORDERS OVER ONE OR MORE GENERATIONS. 2022 17 2300 23 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 18 4510 30 MTOR-DEPENDENT OXIDATIVE STRESS REGULATES OXLDL-INDUCED TRAINED INNATE IMMUNITY IN HUMAN MONOCYTES. INTRODUCTION: CELLS OF THE INNATE IMMUNE SYSTEM PARTICULARLY MONOCYTES AND MACROPHAGES HAVE BEEN RECOGNIZED AS PIVOTAL PLAYERS BOTH DURING THE INITIAL INSULT AS WELL AS THE CHRONIC PHASE OF ATHEROSCLEROSIS. IT HAS RECENTLY BEEN SHOWN THAT OXIDIZED LOW-DENSITY LIPOPROTEIN (OXLDL) INDUCES A LONG-TERM PRO-INFLAMMATORY RESPONSE IN MONOCYTES DUE TO EPIGENETIC AND METABOLIC REPROGRAMMING, AN EMERGING NEW CONCEPT CALLED TRAINED INNATE IMMUNITY. CHANGES IN THE CELLULAR REDOX STATE ARE CRUCIAL EVENTS IN THE REGULATION OF MANY PHYSIOLOGIC FUNCTIONS IN MACROPHAGES INCLUDING TRANSCRIPTION, DIFFERENTIATION AND INFLAMMATORY RESPONSE. HERE WE HAVE ANALYZED THE ROLE OF REACTIVE OXYGEN SPECIES (ROS) IN REGULATING THIS PROINFLAMMATORY MONOCYTE PRIMING IN RESPONSE TO OXLDL-TREATMENT. METHODS AND RESULTS: HUMAN MONOCYTES WERE ISOLATED AND INCUBATED WITH OXLDL FOR 24 H. AFTER 5 DAYS OF RESTING, OXLDL TREATED CELLS PRODUCED SIGNIFICANTLY MORE INFLAMMATORY CYTOKINES UPON RESTIMULATION WITH THE TLR2-AGONIST PAM3CYS. FURTHERMORE, OXLDL INCUBATION INDUCED PERSISTENT MTOR ACTIVATION, ROS FORMATION, HIF1ALPHA ACCUMULATION AND HIF1ALPHA TARGET GENE EXPRESSION, WHILE PHARMACOLOGIC MTOR INHIBITION OR SIRNA MEDIATED INHIBITION OF THE MTORC1 SUBUNIT RAPTOR PREVENTED ROS FORMATION AND PROINFLAMMATORY PRIMING. MTOR DEPENDENT ROS FORMATION WAS ASSOCIATED WITH INCREASED EXPRESSION OF NAPDH OXIDASES AND NECESSARY FOR THE EMERGENCE OF THE PRIMED PHENOTYPE AS ANTIOXIDANT TREATMENT BLOCKED OXLDL PRIMING. INHIBITION OF CYTOSOLIC ROS FORMATION COULD ALSO BLOCK MTOR ACTIVATION AND HIF1ALPHA ACCUMULATION SUGGESTING A POSITIVE FEEDBACK LOOP BETWEEN MTOR AND CYTOSOLIC ROS. ALTHOUGH MITOCHONDRIAL ROS SCAVENGING DID NOT BLOCK HIF1ALPHA-ACCUMULATION AT AN EARLY TIME POINT (24 H), IT WAS PERSISTENTLY REDUCED ON DAY 6. THEREFORE, MITOCHONDRIAL ROS FORMATION APPEARS TO OCCUR INITIALLY DOWNSTREAM OF THE MTOR-CYTOROS-HIF1ALPHA FEEDBACK LOOP BUT SEEMS TO BE A CRUCIAL FACTOR THAT CONTROLS THE LONG-TERM ACTIVATION OF THE MTOR-HIF1ALPHA-AXIS. CONCLUSION: IN SUMMARY, OUR DATA DEMONSTRATE THAT MTOR DEPENDENT ROS PRODUCTION CONTROLS THE OXLDL-INDUCED TRAINED INNATE IMMUNITY PHENOTYPE IN HUMAN MONOCYTE DERIVED MACROPHAGES. PHARMACOLOGIC MODULATION OF THESE PATHWAYS MIGHT PROVIDE A POTENTIAL APPROACH TO MODULATE INFLAMMATION, ASSOCIATED WITH ABERRANT MONOCYTE ACTIVATION, DURING ATHEROSCLEROSIS DEVELOPMENT. 2018 19 5052 19 PHARMACOLOGICAL TARGETING OF HEME OXYGENASE-1 IN OSTEOARTHRITIS. OSTEOARTHRITIS (OA) IS A COMMON AGING-ASSOCIATED DISEASE THAT CLINICALLY MANIFESTS AS JOINT PAIN, MOBILITY LIMITATIONS, AND COMPROMISED QUALITY OF LIFE. TODAY, OA TREATMENT IS LIMITED TO PAIN MANAGEMENT AND JOINT ARTHROPLASTY AT THE LATER STAGES OF DISEASE PROGRESSION. OA PATHOGENESIS IS PREDOMINANTLY MEDIATED BY OXIDATIVE DAMAGE TO JOINT CARTILAGE EXTRACELLULAR MATRIX AND LOCAL CELLS SUCH AS CHONDROCYTES, OSTEOCLASTS, OSTEOBLASTS, AND SYNOVIAL FIBROBLASTS. UNDER NORMAL CONDITIONS, CELLS PREVENT THE ACCUMULATION OF REACTIVE OXYGEN SPECIES (ROS) UNDER OXIDATIVELY STRESSFUL CONDITIONS THROUGH THEIR ADAPTIVE CYTOPROTECTIVE MECHANISMS. HEME OXYGENASE-1 (HO-1) IS AN IRON-DEPENDENT CYTOPROTECTIVE ENZYME THAT FUNCTIONS AS THE INDUCIBLE FORM OF HO. HO-1 AND ITS METABOLITES CARBON MONOXIDE AND BILIVERDIN CONTRIBUTE TOWARDS THE MAINTENANCE OF REDOX HOMEOSTASIS. HO-1 EXPRESSION IS PRIMARILY REGULATED AT THE TRANSCRIPTIONAL LEVEL THROUGH TRANSCRIPTIONAL FACTOR NUCLEAR FACTOR ERYTHROID 2 (NF-E2)-RELATED FACTOR 2 (NRF2), SPECIFICITY PROTEIN 1 (SP1), TRANSCRIPTIONAL REPRESSOR BTB-AND-CNC HOMOLOGY 1 (BACH1), AND EPIGENETIC REGULATION. SEVERAL STUDIES REPORT THAT HO-1 EXPRESSION CAN BE REGULATED USING VARIOUS ANTIOXIDATIVE FACTORS AND CHEMICAL COMPOUNDS, SUGGESTING THERAPEUTIC IMPLICATIONS IN OA PATHOGENESIS AS WELL AS IN THE WIDER CONTEXT OF JOINT DISEASE. HERE, WE REVIEW THE PROTECTIVE ROLE OF HO-1 IN OA WITH A FOCUS ON THE REGULATORY MECHANISMS THAT MEDIATE HO-1 ACTIVITY. 2021 20 4704 23 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