1 5052 132 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 2 616 38 BIOACTIVE COMPOUNDS IN OXIDATIVE STRESS-MEDIATED DISEASES: TARGETING THE NRF2/ARE SIGNALING PATHWAY AND EPIGENETIC REGULATION. OXIDATIVE STRESS IS A PATHOLOGICAL CONDITION OCCURRING DUE TO AN IMBALANCE BETWEEN THE OXIDANTS AND ANTIOXIDANT DEFENSE SYSTEMS IN THE BODY. NUCLEAR FACTOR E2-RELATED FACTOR 2 (NRF2), ENCODED BY THE GENE NFE2L2, IS THE MASTER REGULATOR OF PHASE II ANTIOXIDANT ENZYMES THAT PROTECT AGAINST OXIDATIVE STRESS AND INFLAMMATION. NRF2/ARE SIGNALING HAS BEEN CONSIDERED AS A PROMISING TARGET AGAINST OXIDATIVE STRESS-MEDIATED DISEASES LIKE DIABETES, FIBROSIS, NEUROTOXICITY, AND CANCER. THE CONSUMPTION OF DIETARY PHYTOCHEMICALS ACTS AS AN EFFECTIVE MODULATOR OF NRF2/ARE IN VARIOUS ACUTE AND CHRONIC DISEASES. IN THE PRESENT REVIEW, WE DISCUSSED THE ROLE OF NRF2 IN DIABETES, ALZHEIMER'S DISEASE (AD), PARKINSON'S DISEASE (PD), CANCER, AND ATHEROSCLEROSIS. ADDITIONALLY, WE DISCUSSED THE PHYTOCHEMICALS LIKE CURCUMIN, QUERCETIN, RESVERATROL, EPIGALLOCATECHIN GALLATE, APIGENIN, SULFORAPHANE, AND URSOLIC ACID THAT HAVE EFFECTIVELY MODIFIED NRF2 SIGNALING AND PREVENTED VARIOUS DISEASES IN BOTH IN VITRO AND IN VIVO MODELS. BASED ON THE LITERATURE, IT IS CLEAR THAT DIETARY PHYTOCHEMICALS CAN PREVENT DISEASES BY (1) BLOCKING OXIDATIVE STRESS-INHIBITING INFLAMMATORY MEDIATORS THROUGH INHIBITING KEAP1 OR ACTIVATING NRF2 EXPRESSION AND ITS DOWNSTREAM TARGETS IN THE NUCLEUS, INCLUDING HO-1, SOD, AND CAT; (2) REGULATING NRF2 SIGNALING BY VARIOUS KINASES LIKE GSK3BETA, PI3/AKT, AND MAPK; AND (3) MODIFYING EPIGENETIC MODULATION, SUCH AS METHYLATION, AT THE NRF2 PROMOTER REGION; HOWEVER, FURTHER INVESTIGATION INTO OTHER UPSTREAM SIGNALING MOLECULES LIKE NRF2 AND THE EFFECT OF PHYTOCHEMICALS ON THEM STILL NEED TO BE INVESTIGATED IN THE NEAR FUTURE. 2021 3 6045 34 THE COMPLEXITY OF THE NRF2 PATHWAY: BEYOND THE ANTIOXIDANT RESPONSE. THE NF-E2-RELATED FACTOR 2 (NRF2)-MEDIATED SIGNALLING PATHWAY PROVIDES LIVING ORGANISMS AN EFFICIENT AND PIVOTAL LINE OF DEFENSIVE TO COUNTERACT ENVIRONMENTAL INSULTS AND ENDOGENOUS STRESSORS. NRF2 COORDINATES THE BASAL AND INDUCIBLE EXPRESSION OF ANTIOXIDANT AND PHASE II DETOXIFICATION ENZYMES TO ADAPT TO DIFFERENT STRESS CONDITIONS. THE STABILITY AND CELLULAR DISTRIBUTION OF NRF2 IS TIGHTLY CONTROLLED BY ITS INHIBITORY BINDING PROTEIN KELCH-LIKE ECH-ASSOCIATED PROTEIN 1. NRF2 SIGNALLING IS ALSO REGULATED BY POSTTRANSLATIONAL, TRANSCRIPTIONAL, TRANSLATIONAL AND EPIGENETIC MECHANISMS, AS WELL AS BY OTHER PROTEIN PARTNERS, INCLUDING P62, P21 AND IQ MOTIF-CONTAINING GTPASE ACTIVATING PROTEIN 1. MANY STUDIES HAVE DEMONSTRATED THAT NRF2 IS A PROMISING TARGET FOR PREVENTING CARCINOGENESIS AND OTHER CHRONIC DISEASES, INCLUDING CARDIOVASCULAR DISEASES, NEURODEGENERATIVE DISEASES AND PULMONARY INJURY. HOWEVER, CONSTITUTIVE ACTIVATION OF NRF2 IN ADVANCED CANCER CELLS MAY CONFER DRUG RESISTANCE. HERE, WE REVIEW THE MOLECULAR MECHANISMS OF NRF2 SIGNALLING, THE DIVERSE CLASSES OF NRF2 ACTIVATORS, INCLUDING BIOACTIVE NUTRIENTS AND OTHER CHEMICALS, AND THE CELLULAR FUNCTIONS AND DISEASE RELEVANCE OF NRF2 AND DISCUSS THE DUAL ROLE OF NRF2 IN DIFFERENT CONTEXTS. 2015 4 1413 35 DIETARY PHYTOCHEMICALS AND CANCER CHEMOPREVENTION: A PERSPECTIVE ON OXIDATIVE STRESS, INFLAMMATION, AND EPIGENETICS. OXIDATIVE STRESS OCCURS WHEN CELLULAR REACTIVE OXYGEN SPECIES LEVELS EXCEED THE SELF-ANTIOXIDANT CAPACITY OF THE BODY. OXIDATIVE STRESS INDUCES MANY PATHOLOGICAL CHANGES, INCLUDING INFLAMMATION AND CANCER. CHRONIC INFLAMMATION IS BELIEVED TO BE STRONGLY ASSOCIATED WITH THE MAJOR STAGES OF CARCINOGENESIS. THE NUCLEAR FACTOR ERYTHROID 2-RELATED FACTOR 2 (NRF2) PATHWAY PLAYS A CRUCIAL ROLE IN REGULATING OXIDATIVE STRESS AND INFLAMMATION BY MANIPULATING KEY ANTIOXIDANT AND DETOXIFICATION ENZYME GENES VIA THE ANTIOXIDANT RESPONSE ELEMENT. MANY DIETARY PHYTOCHEMICALS WITH CANCER CHEMOPREVENTIVE PROPERTIES, SUCH AS POLYPHENOLS, ISOTHIOCYANATES, AND TRITERPENOIDS, EXERT ANTIOXIDANT AND ANTI-INFLAMMATORY FUNCTIONS BY ACTIVATING THE NRF2 PATHWAY. FURTHERMORE, EPIGENETIC CHANGES, INCLUDING DNA METHYLATION, HISTONE POST-TRANSLATIONAL MODIFICATIONS, AND MIRNA-MEDIATED POST-TRANSCRIPTIONAL ALTERATIONS, ALSO LEAD TO VARIOUS CARCINOGENESIS PROCESSES BY SUPPRESSING CANCER REPRESSOR GENE TRANSCRIPTION. USING EPIGENETIC RESEARCH TOOLS, INCLUDING NEXT-GENERATION SEQUENCING TECHNOLOGIES, MANY DIETARY PHYTOCHEMICALS ARE SHOWN TO MODIFY AND REVERSE ABERRANT EPIGENETIC/EPIGENOME CHANGES, POTENTIALLY LEADING TO CANCER PREVENTION/TREATMENT. THUS, THE BENEFICIAL EFFECTS OF DIETARY PHYTOCHEMICALS ON CANCER DEVELOPMENT WARRANT FURTHER INVESTIGATION TO PROVIDE ADDITIONAL IMPETUS FOR CLINICAL TRANSLATIONAL STUDIES. 2016 5 4836 41 ONCOGENIC FUNCTIONS OF THE TRANSCRIPTION FACTOR NRF2. NUCLEAR FACTOR E2-RELATED FACTOR 2 (NRF2) IS A TRANSCRIPTION FACTOR THAT CONTROLS THE EXPRESSION OF A LARGE POOL OF ANTIOXIDANT AND CYTOPROTECTIVE GENES REGULATING THE CELLULAR RESPONSE TO OXIDATIVE AND ELECTROPHILIC STRESS. NRF2 IS NEGATIVELY REGULATED BY KELCH-LIKE ECH-ASSOCIATED PROTEIN 1 (KEAP1) AND, UPON STIMULATION BY AN OXIDATIVE OR ELECTROPHILIC INSULT, IS RAPIDLY ACTIVATED BY PROTEIN STABILIZATION. OWING TO ITS CYTOPROTECTIVE FUNCTIONS, NRF2 HAS BEEN TRADITIONALLY STUDIED IN THE FIELD OF CHEMOPREVENTION; HOWEVER, THERE IS ACCUMULATED EVIDENCE THAT KEAP1/NRF2 MUTATIONS OR UNBALANCED REGULATION THAT LEADS TO OVEREXPRESSION OR HYPERACTIVATION OF NRF2 MAY PARTICIPATE IN TUMORIGENESIS AND BE INVOLVED IN CHEMORESISTANCE OF A WIDE NUMBER OF SOLID CANCERS AND LEUKEMIAS. IN ADDITION TO PROTECTING CELLS FROM REACTIVE OXYGEN SPECIES, NRF2 SEEMS TO PLAY A DIRECT ROLE IN CELL GROWTH CONTROL AND IS RELATED TO APOPTOSIS-REGULATING PATHWAYS. MOREOVER, NRF2 ACTIVITY IS CONNECTED WITH ONCOGENIC KINASE PATHWAYS, STRUCTURAL PROTEINS, HORMONAL REGULATION, OTHER TRANSCRIPTION FACTORS, AND EPIGENETIC ENZYMES INVOLVED IN THE PATHOGENESIS OF VARIOUS TYPES OF TUMORS. THE AIM OF THIS REVIEW IS TO COMPILE AND SUMMARIZE EXISTING KNOWLEDGE OF THE ONCOGENIC FUNCTIONS OF NRF2 TO PROVIDE A SOLID BASIS FOR ITS POTENTIAL USE AS A MOLECULAR MARKER AND PHARMACOLOGICAL TARGET IN CANCER. 2013 6 4044 23 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 7 3355 27 HISTONE EXTRACTION FROM HUMAN ARTICULAR CARTILAGE FOR THE STUDY OF EPIGENETIC REGULATION IN OSTEOARTHRITIS. OSTEOARTHRITIS (OA) IS A CHRONIC DISEASE THAT AFFECTS ARTICULAR CARTILAGE, CAUSING ITS DEGENERATION. ALTHOUGH OA IS ONE OF THE MOST PREVALENT PATHOLOGIES GLOBALLY, THERE ARE NO DEFINITIVE TREATMENTS AVAILABLE. RECENTLY, RESEARCH HAS FOCUSED ON ELUCIDATING THE COMPLEX INTERPLAY THAT TAKES PLACE BETWEEN INFLAMMATORY PROCESSES AND EPIGENETIC REGULATION, SHOWING THAT HISTONE POST-TRANSLATIONAL MODIFICATIONS (PTMS) CAN EXERT A PRONOUNCED EFFECT ON THE EXPRESSION OF OA-RELATED GENES. OA CHONDROCYTES ENHANCE THE PRODUCTION OF INTERLEUKIN 1BETA (IL-1BETA) AND INTERLEUKIN 8 (IL-8), WHICH ARE EPIGENETICALLY REGULATED. THESE CYTOKINES UPREGULATE THE SYNTHESIS OF MATRIX METALLOPROTEINASES (MMPS) AND AGGRECANASES, WHICH PROMOTE THE EXTRACELLULAR MATRIX (ECM) DESTRUCTION. THIS MOTIVATES THE STUDY OF HISTONE PTMS TO INVESTIGATE THE EPIGENETIC REGULATION OF PROINFLAMMATORY MOLECULES, BUT THE ABSENCE OF SPECIFIC PROTOCOLS TO EXTRACT HISTONES FROM HUMAN ARTICULAR CARTILAGE HAS COMPLICATED THIS TASK. THE LACK OF EFFECTIVE METHODS CAN BE EXPLAINED BY THE STRUCTURAL COMPLEXITY AND LOW CELLULARITY OF THIS TISSUE, WHICH ARE RESPONSIBLE FOR THE BIOMECHANICAL PROPERTIES THAT ALLOW THE MOVEMENT OF THE JOINT BUT ALSO COMPLICATE HISTONE ISOLATION. HERE, WE PROVIDE A HISTONE EXTRACTION PROCEDURE SPECIFICALLY ADAPTED FOR CRYOPRESERVED HUMAN ARTICULAR CARTILAGE THAT CAN BE USEFUL TO UNDERSTAND EPIGENETIC REGULATION IN OA AND ACCELERATE THE SEARCH FOR NOVEL STRATEGIES. 2022 8 4679 32 NEW MOLECULAR TARGETS FOR THE TREATMENT OF OSTEOARTHRITIS. OSTEOARTHRITIS (OA) IS A CHRONIC DEGENERATIVE JOINT DISORDER CHARACTERIZED BY DESTRUCTION OF THE ARTICULAR CARTILAGE, SUBCHONDRAL BONE ALTERATIONS AND SYNOVITIS. CURRENT TREATMENTS ARE FOCUSED ON SYMPTOMATIC RELIEF BUT THEY LACK EFFICACY TO CONTROL THE PROGRESSION OF THIS DISEASE WHICH IS A LEADING CAUSE OF DISABILITY. THEREFORE, THE DEVELOPMENT OF EFFECTIVE DISEASE-MODIFYING DRUGS IS URGENTLY NEEDED. DIFFERENT INITIATIVES ARE IN PROGRESS TO DEFINE THE MOLECULAR MECHANISMS INVOLVED IN THE INITIATION AND PROGRESSION OF OA. THESE STUDIES SUPPORT THE THERAPEUTIC POTENTIAL OF PATHWAYS RELEVANT IN JOINT METABOLISM SUCH AS WNT/BETA-CATENIN, DISCOIDIN DOMAIN RECEPTOR 2 OR PROTEINASE-ACTIVATED RECEPTOR 2. THE DYSREGULATION IN CARTILAGE CATABOLISM AND SUBCHONDRAL BONE REMODELING COULD BE IMPROVED BY SELECTIVE INHIBITORS OF MATRIX METALLOPROTEINASES, AGGRECANASES AND OTHER PROTEASES. ANOTHER APPROACH WOULD FAVOR THE ACTIVITY OF ANABOLIC PROCESSES BY USING GROWTH FACTORS OR REGULATORY MOLECULES. RECENT STUDIES HAVE ALSO REVEALED THE ROLE OF OXIDATIVE STRESS AND SYNOVITIS IN THE PROGRESSION OF THIS DISEASE, SUPPORTING THE DEVELOPMENT OF A NUMBER OF INHIBITORY STRATEGIES. NOVEL TARGETS IN OA ARE REPRESENTED BY GENES INVOLVED IN OA PATHOPHYSIOLOGY DISCOVERED USING GENE NETWORK, EPIGENETIC AND MICRORNA APPROACHES. FURTHER INSIGHTS INTO THE MOLECULAR MECHANISMS INVOLVED IN OA INITIATION AND PROGRESSION MAY LEAD TO THE DEVELOPMENT OF NEW THERAPIES ABLE TO CONTROL JOINT DESTRUCTION AND REPAIR. 2010 9 4898 37 OXIDATIVE STRESS INDUCED LUNG CANCER AND COPD: OPPORTUNITIES FOR EPIGENETIC THERAPY. REACTIVE OXYGEN SPECIES (ROS) FORM AS A NATURAL BY-PRODUCT OF THE NORMAL METABOLISM OF OXYGEN AND PLAY IMPORTANT ROLES WITHIN THE CELL. UNDER NORMAL CIRCUMSTANCES THE CELL IS ABLE TO MAINTAIN AN ADEQUATE HOMEOSTASIS BETWEEN THE FORMATION OF ROS AND ITS REMOVAL THROUGH PARTICULAR ENZYMATIC PATHWAYS OR VIA ANTIOXIDANTS. IF HOWEVER, THIS BALANCE IS DISTURBED A SITUATION CALLED OXIDATIVE STRESS OCCURS. CRITICALLY, OXIDATIVE STRESS PLAYS IMPORTANT ROLES IN THE PATHOGENESIS OF MANY DISEASES, INCLUDING CANCER. EPIGENETICS IS A PROCESS WHERE GENE EXPRESSION IS REGULATED BY HERITABLE MECHANISMS THAT DO NOT CAUSE ANY DIRECT CHANGES TO THE DNA SEQUENCE ITSELF, AND DISRUPTION OF EPIGENETIC MECHANISMS HAS IMPORTANT IMPLICATIONS IN DISEASE. EVIDENCE IS EMERGING THAT HISTONE DEACETYLASES (HDACS) PLAY DECISIVE ROLES IN REGULATING IMPORTANT CELLULAR OXIDATIVE STRESS PATHWAYS INCLUDING THOSE INVOLVED WITH SENSING OXIDATIVE STRESS AND THOSE INVOLVED WITH REGULATING THE CELLULAR RESPONSE TO OXIDATIVE STRESS. IN PARTICULAR ABERRANT REGULATION OF THESE PATHWAYS BY HDACS MAY PLAY CRITICAL ROLES IN CANCER PROGRESSION. IN THIS REVIEW WE DISCUSS THE CURRENT EVIDENCE LINKING EPIGENETICS AND OXIDATIVE STRESS AND CANCER, USING CHRONIC OBSTRUCTIVE PULMONARY DISEASE AND NON-SMALL CELL LUNG CANCER TO ILLUSTRATE THE IMPORTANCE OF EPIGENETICS ON THESE PATHWAYS WITHIN THESE DISEASE SETTINGS. 2009 10 1416 34 DIETARY POLYPHENOLS REMODEL DNA METHYLATION PATTERNS OF NRF2 IN CHRONIC DISEASE. THE NUCLEAR FACTOR ERYTHROID 2-RELATED FACTOR 2 (NRF2) IS A TRANSCRIPTION FACTOR CRUCIAL IN REGULATING CELLULAR HOMEOSTASIS AND APOPTOSIS. THE NRF2 GENE HAS BEEN IMPLICATED IN VARIOUS BIOLOGICAL ACTIVITIES, INCLUDING ANTIOXIDANT, ANTI-INFLAMMATORY, AND ANTICANCER PROPERTIES. NRF2 CAN BE REGULATED GENETICALLY AND EPIGENETICALLY AT THE TRANSCRIPTIONAL, POST-TRANSCRIPTIONAL, AND TRANSLATIONAL LEVELS. ALTHOUGH DNA METHYLATION IS ONE OF THE CRITICAL BIOLOGICAL PROCESSES VITAL FOR GENE EXPRESSION, SOMETIMES, ANOMALOUS METHYLATION PATTERNS RESULT IN THE DYSREGULATION OF GENES AND CONSEQUENT DISEASES AND DISORDERS. SEVERAL STUDIES HAVE REPORTED PROMOTER HYPERMETHYLATION DOWNREGULATED NRF2 EXPRESSION AND ITS DOWNSTREAM TARGETS. IN CONTRAST TO THE UNALTERABLE NATURE OF GENETIC PATTERNS, EPIGENETIC CHANGES CAN BE REVERSED, OPENING UP NEW POSSIBILITIES IN DEVELOPING THERAPIES FOR VARIOUS METABOLIC DISORDERS AND DISEASES. THIS REVIEW DISCUSSES THE CURRENT STATE OF THE NRF2-MEDIATED ANTIOXIDATIVE AND CHEMOPREVENTIVE ACTIVITIES OF SEVERAL NATURAL PHYTOCHEMICALS, INCLUDING SULFORAPHANE, RESVERATROL, CURCUMIN, LUTEOLIN, COROSOLIC ACID, APIGENIN, AND MOST OTHER COMPOUNDS THAT HAVE BEEN FOUND TO ACTIVATE NRF2. THIS EPIGENETIC REVERSAL OF HYPERMETHYLATED NRF2 STATES PROVIDES NEW OPPORTUNITIES FOR RESEARCH INTO DIETARY PHYTOCHEMISTRY THAT AFFECTS THE HUMAN EPIGENOME AND THE POSSIBILITY FOR CUTTING-EDGE APPROACHES TO TARGET NRF2-MEDIATED SIGNALING TO PREVENT CHRONIC DISORDERS. 2023 11 4738 37 NOVEL FIBROBLAST PHENOTYPES IN HOMEOSTASIS AND CHRONIC INFLAMMATION: FROM FUNCTIONS TO POTENTIAL REGULATORS. FIBROBLASTS ARE ESSENTIAL COMPONENTS OF THE STROMA, SUSTAINING A VARIETY OF TISSUES AND BEING KEY TO THE PROCESS OF TISSUE REPAIR AFTER INJURY. THEIR ROLE IN TISSUE REPAIR HAS BEEN ATTRIBUTED TO THEIR ABILITY TO ACQUIRE A CONTRACTILE, EXTRACELLULAR MATRIX-PRODUCING PHENOTYPE KNOWN AS MYOFIBROBLASTS. THIS PROPERTY IS PRIMARILY DEPENDENT ON THEIR RESPONSE TO THE PLEIOTROPIC CYTOKINE TRANSFORMING GROWTH FACTOR-BETA1. UNTIL RECENTLY, THE POTENTIAL ROLE OF FIBROBLASTS IN OTHER HOMEOSTATIC AND DISEASE-RELATED PROCESSES WAS LESS WELL UNDERSTOOD. ALTHOUGH IN VITRO STUDIES INDICATED THAT FIBROBLASTS ARE ABLE TO RESPOND TO AND SECRETE INFLAMMATORY MEDIATORS, DEFINITIVE EVIDENCE OF THEIR CONTRIBUTION TO CHRONIC INFLAMMATION WAS LIMITED. HOWEVER, THE EMERGENCE OF TECHNIQUES THAT ALLOW EXPLORATION OF TISSUES AT THE SINGLE CELL LEVEL HAS CHALLENGED THE PREVIOUS PARADIGMS ON FIBROBLAST IDENTITY AND FUNCTIONS, AND HAS LED TO THE DISCOVERY OF SIGNIFICANT DIVERSITY, SHOWING THE PRESENCE OF FIBROBLASTS WITH ALTERNATE TRANSCRIPTIONAL PROFILES IN A VARIETY OF TISSUES. THESE STUDIES HAVE ALSO SUGGESTED POTENTIAL ROLES OF NOVEL FIBROBLAST SUBTYPES AS REGULATORS OF EPITHELIAL HOMEOSTASIS AND RENEWAL, INFLAMMATORY CELL INFILTRATION AND ACTIVATION, AND ANTIGEN PRESENTATION. HERE, WE PROVIDE A COMPREHENSIVE REVIEW OF THE RECENT LITERATURE ON FIBROBLAST DIVERSITY IN THE DIGESTIVE TRACT, SKIN, LUNGS AND JOINTS. WE ALSO REVIEW EVIDENCE OF THEIR CONTRIBUTION TO THE REGULATION OF HOMEOSTASIS AND CHRONIC INFLAMMATION, AS WELL AS THEIR INTERACTIONS WITH OTHER CELLS IN VARIOUS TISSUE COMPARTMENTS. WE DISCUSS EVIDENCE OF DIFFERENT FACTORS INVOLVED IN THE CONTROL OF FIBROBLAST FUNCTION, ADDRESSING THE ROLE OF VARIOUS CYTOKINES, TRANSCRIPTION FACTORS AND EPIGENETIC CHANGES, AS WELL AS MICROENVIRONMENTAL FACTORS, INCLUDING EXTRACELLULAR MATRIX STIFFNESS, HYPOXIA, AND METABOLIC SHIFTS. 2023 12 5942 35 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 13 4453 34 MOLECULAR MECHANISMS AND PATHWAYS AS TARGETS FOR CANCER PREVENTION AND PROGRESSION WITH DIETARY COMPOUNDS. A UNIQUE FEATURE OF BIOACTIVE FOOD INGREDIENTS IS THEIR BROAD ANTIOXIDANT FUNCTION. ANTIOXIDANTS HAVING A WIDE SPECTRUM OF CHEMICAL STRUCTURE AND ACTIVITY BEYOND BASIC NUTRITION; DISPLAY DIFFERENT HEALTH BENEFITS BY THE PREVENTION AND PROGRESSION OF CHRONIC DISEASES. FUNCTIONAL FOOD COMPONENTS ARE CAPABLE OF ENHANCING THE NATURAL ANTIOXIDANT DEFENSE SYSTEM BY SCAVENGING REACTIVE OXYGEN AND NITROGEN SPECIES, PROTECTING AND REPAIRING DNA DAMAGE, AS WELL AS MODULATING THE SIGNAL TRANSDUCTION PATHWAYS AND GENE EXPRESSION. MAJOR PATHWAYS AFFECTED BY BIOACTIVE FOOD INGREDIENTS INCLUDE THE PRO-INFLAMMATORY PATHWAYS REGULATED BY NUCLEAR FACTOR KAPPA B (NF-KAPPAB), AS WELL AS THOSE ASSOCIATED WITH CYTOKINES AND CHEMOKINES. THE PRESENT REVIEW SUMMARIZES THE IMPORTANCE OF PLANT BIOACTIVES AND THEIR ROLES IN THE REGULATION OF INFLAMMATORY PATHWAYS. BIOACTIVES INFLUENCE SEVERAL PHYSIOLOGICAL PROCESSES SUCH AS GENE EXPRESSION, CELL CYCLE REGULATION, CELL PROLIFERATION, CELL MIGRATION, ETC., RESULTING IN CANCER PREVENTION. CANCER INITIATION IS ASSOCIATED WITH CHANGES IN METABOLIC PATHWAYS SUCH AS GLUCOSE METABOLISM, AND THE EFFECT OF BIOACTIVES IN NORMALIZING THIS PROCESS HAS BEEN PROVIDED. INITIATION AND PROGRESSION OF INFLAMMATORY BOWEL DISEASES (IBD) WHICH INCREASE THE CHANCES OF DEVELOPING OF COLORECTAL CANCERS CAN BE DOWNREGULATED BY PLANT BIOACTIVES. SEVERAL ASPECTS OF THE POTENTIAL ROLES OF MICRORNAS AND EPIGENETIC MODIFICATIONS IN THE DEVELOPMENT OF CANCERS HAVE ALSO BEEN PRESENTED. 2017 14 2508 32 EPIGENETICS AND OSTEOARTHRITIS. OSTEOARTHRITIS (OA) IS THE MOST COMMON FORM OF JOINT DISEASE AND THE LEADING CAUSE OF CHRONIC DISABILITY IN MIDDLE-AGED AND OLDER POPULATIONS. THE DEVELOPMENT OF DISEASE-MODIFYING THERAPY FOR OA CURRENTLY FACES MAJOR OBSTACLES LARGELY BECAUSE THE REGULATORY MECHANISMS FOR THE FUNCTION OF JOINT TISSUE CELLS REMAIN UNCLEAR. PREVIOUS STUDIES HAVE FOUND THAT THE ALTERATIONS IN GENE EXPRESSION OF SPECIFIC TRANSCRIPTION FACTORS (TFS), PRO- OR ANTI-INFLAMMATORY CYTOKINES, MATRIX PROTEINASES AND EXTRACELLULAR MATRIX (ECM) PROTEINS IN ARTICULAR CARTILAGE MAY BE INVOLVED IN THE DEVELOPMENT OF OA. HOWEVER, THE REGULATORY MECHANISMS FOR THE EXPRESSION OF THOSE GENES IN OA CHONDROCYTES ARE LARGELY UNKNOWN. THE RECENT ADVANCES IN EPIGENETIC STUDIES HAVE SHED LIGHTS ON THE IMPORTANCE OF EPIGENETIC REGULATION OF GENE EXPRESSION IN THE DEVELOPMENT OF OA. IN THIS REVIEW, WE SUMMARIZE AND DISCUSS THE RECENT STUDIES ON THE REGULATORY ROLES OF VARIOUS EPIGENETIC MECHANISMS IN THE EXPRESSION OF GENES FOR SPECIFIC TFS, CYTOKINES, ECM PROTEINS AND MATRIX PROTEINASES, AS WELL THE SIGNIFICANCE OF THESE EPIGENETIC MECHANISMS IN THE PATHOGENESIS OF OA. 2015 15 5937 34 TARGETING HISTONE DEACETYLASE ACTIVITY IN RHEUMATOID ARTHRITIS AND ASTHMA AS PROTOTYPES OF INFLAMMATORY DISEASE: SHOULD WE KEEP OUR HATS ON? CELLULAR ACTIVATION, PROLIFERATION AND SURVIVAL IN CHRONIC INFLAMMATORY DISEASES IS REGULATED NOT ONLY BY ENGAGEMENT OF SIGNAL TRANS-DUCTION PATHWAYS THAT MODULATE TRANSCRIPTION FACTORS REQUIRED FOR THESE PROCESSES, BUT ALSO BY EPIGENETIC REGULATION OF TRANSCRIPTION FACTOR ACCESS TO GENE PROMOTER REGIONS. HISTONE ACETYL TRANSFERASES COORDINATE THE RECRUITMENT AND ACTIVATION OF TRANSCRIPTION FACTORS WITH CONFORMATIONAL CHANGES IN HISTONES THAT ALLOW GENE PROMOTER EXPOSURE. HISTONE DEACETYLASES (HDACS) COUNTERACT HISTONE ACETYL TRANSFERASE ACTIVITY THROUGH THE TARGETING OF BOTH HISTONES AS WELL AS NONHISTONE SIGNAL TRANSDUCTION PROTEINS IMPORTANT IN INFLAMMATION. NUMEROUS STUDIES HAVE INDICATED THAT DEPRESSED HDAC ACTIVITY IN PATIENTS WITH INFLAMMATORY AIRWAY DISEASES MAY CONTRIBUTE TO LOCAL PROINFLAMMATORY CYTOKINE PRODUCTION AND DIMINISH PATIENT RESPONSES TO CORTICOSTEROID TREATMENT. RECENT OBSERVATIONS THAT HDAC ACTIVITY IS DEPRESSED IN RHEUMATOID ARTHRITIS PATIENT SYNOVIAL TISSUE HAVE PREDICTED THAT STRATEGIES RESTORING HDAC FUNCTION MAY BE THERAPEUTIC IN THIS DISEASE AS WELL. PHARMACOLOGICAL INHIBITORS OF HDAC ACTIVITY, HOWEVER, HAVE DEMONSTRATED POTENT THERAPEUTIC EFFECTS IN ANIMAL MODELS OF ARTHRITIS AND OTHER CHRONIC INFLAMMATORY DISEASES. IN THE PRESENT REVIEW WE ASSESS AND RECONCILE THESE OUTWARDLY PARADOXICAL STUDY RESULTS TO PROVIDE A WORKING MODEL FOR HOW ALTERATIONS IN HDAC ACTIVITY MAY CONTRIBUTE TO PATHOLOGY IN RHEUMATOID ARTHRITIS, AND HIGHLIGHT KEY QUESTIONS TO BE ANSWERED IN THE PRECLINICAL EVALUATION OF COMPOUNDS MODULATING THESE ENZYMES. 2008 16 4427 38 MOLECULAR BASIS OF ELECTROPHILIC AND OXIDATIVE DEFENSE: PROMISES AND PERILS OF NRF2. INDUCTION OF DRUG-METABOLIZING ENZYMES THROUGH THE ANTIOXIDANT RESPONSE ELEMENT (ARE)-DEPENDENT TRANSCRIPTION WAS INITIALLY IMPLICATED IN CHEMOPREVENTION AGAINST CANCER BY ANTIOXIDANTS. RECENT PROGRESS IN UNDERSTANDING THE BIOLOGY AND MECHANISM OF INDUCTION REVEALED A CRITICAL ROLE OF INDUCTION IN CELLULAR DEFENSE AGAINST ELECTROPHILIC AND OXIDATIVE STRESS. INDUCTION IS MEDIATED THROUGH A NOVEL SIGNALING PATHWAY VIA TWO REGULATORY PROTEINS, THE NUCLEAR FACTOR ERYTHROID 2-RELATED FACTOR 2 (NRF2) AND THE KELCH-LIKE ERYTHROID CELL-DERIVED PROTEIN WITH CNC HOMOLOGY-ASSOCIATED PROTEIN 1 (KEAP1). NRF2 BINDS TO KEAP1 AT A TWO SITE-BINDING INTERFACE AND IS UBIQUITINATED BY THE KEAP1/CULLIN 3/RING BOX PROTEIN-1-UBIQUITIN LIGASE, RESULTING IN A RAPID TURNOVER OF NRF2 PROTEIN. ELECTROPHILES AND OXIDANTS MODIFY CRITICAL CYSTEINE THIOLS OF KEAP1 AND NRF2 TO INHIBIT NRF2 UBIQUITINATION, LEADING TO NRF2 ACTIVATION AND INDUCTION. INDUCTION INCREASES STRESS RESISTANCE CRITICAL FOR CELL SURVIVAL, BECAUSE KNOCKOUT OF NRF2 IN MICE INCREASED SUSCEPTIBILITY TO A VARIETY OF TOXICITY AND DISEASE PROCESSES. COLLATERAL TO DIVERSE FUNCTIONS OF NRF2, GENOME-WIDE SEARCH HAS LED TO THE IDENTIFICATION OF A PLETHORA OF ARE-DEPENDENT GENES REGULATED BY NRF2 IN AN INDUCER-, TISSUE-, AND DISEASE-DEPENDENT MANNER TO CONTROL DRUG METABOLISM, ANTIOXIDANT DEFENSE, STRESS RESPONSE, PROTEASOMAL DEGRADATION, AND CELL PROLIFERATION. THE PROTECTIVE NATURE OF NRF2 COULD ALSO BE HIJACKED IN A NUMBER OF PATHOLOGICAL CONDITIONS BY MEANS OF SOMATIC MUTATION, EPIGENETIC ALTERATION, AND ACCUMULATION OF DISRUPTOR PROTEINS, PROMOTING DRUG RESISTANCE IN CANCER AND PATHOLOGIC LIVER FEATURES IN AUTOPHAGY DEFICIENCY. THE REPERTOIRE OF ARE INDUCERS HAS EXPANDED ENORMOUSLY; THE THERAPEUTIC POTENTIAL OF THE INDUCERS HAS BEEN EXAMINED BEYOND CANCER PREVENTION. DEVELOPING POTENT AND SPECIFIC ARE INDUCERS AND NRF2 INHIBITORS HOLDS CERTAIN NEW PROMISE FOR THE PREVENTION AND THERAPY AGAINST CANCER, CHRONIC DISEASE, AND TOXICITY. 2012 17 1383 40 DIABETES AND ITS CARDIOVASCULAR COMPLICATIONS: POTENTIAL ROLE OF THE ACETYLTRANSFERASE P300. DIABETES HAS BEEN SHOWN TO ACCELERATE VASCULAR SENESCENCE, WHICH IS ASSOCIATED WITH CHRONIC INFLAMMATION AND OXIDATIVE STRESS, BOTH IMPLICATED IN THE DEVELOPMENT OF ENDOTHELIAL DYSFUNCTION. THIS CONDITION REPRESENTS THE INITIAL ALTERATION LINKING DIABETES TO RELATED CARDIOVASCULAR (CV) COMPLICATIONS. RECENTLY, IT HAS BEEN HYPOTHESISED THAT THE ACETYLTRANSFERASE, P300, MAY CONTRIBUTE TO ESTABLISHING AN EARLY VASCULAR SENESCENT PHENOTYPE, PLAYING A RELEVANT ROLE IN DIABETES-ASSOCIATED INFLAMMATION AND OXIDATIVE STRESS, WHICH DRIVE ENDOTHELIAL DYSFUNCTION. SPECIFICALLY, P300 CAN MODULATE VASCULAR INFLAMMATION THROUGH EPIGENETIC MECHANISMS AND TRANSCRIPTION FACTORS ACETYLATION. INDEED, IT REGULATES THE INFLAMMATORY PATHWAY BY INTERACTING WITH NUCLEAR FACTOR KAPPA-LIGHT-CHAIN-ENHANCER OF ACTIVATED B CELLS P65 SUBUNIT (NF-KAPPAB P65) OR BY INDUCING ITS ACETYLATION, SUGGESTING A CRUCIAL ROLE OF P300 AS A BRIDGE BETWEEN NF-KAPPAB P65 AND THE TRANSCRIPTIONAL MACHINERY. ADDITIONALLY, P300-MEDIATED EPIGENETIC MODIFICATIONS COULD BE UPSTREAM OF THE ACTIVATION OF INFLAMMATORY CYTOKINES, AND THEY MAY INDUCE OXIDATIVE STRESS BY AFFECTING THE PRODUCTION OF REACTIVE OXYGEN SPECIES (ROS). BECAUSE SEVERAL IN VITRO AND IN VIVO STUDIES SHED LIGHT ON THE POTENTIAL USE OF ACETYLTRANSFERASE INHIBITORS, A BETTER UNDERSTANDING OF THE MECHANISMS UNDERLYING THE ROLE OF P300 IN DIABETIC VASCULAR DYSFUNCTION COULD HELP IN FINDING NEW STRATEGIES FOR THE CLINICAL MANAGEMENT OF CV DISEASES RELATED TO DIABETES. 2023 18 4987 29 PATTERNS OF CALCIUM SIGNALING: A LINK BETWEEN CHRONIC EMOTIONS AND CANCER. INTRA AND INTER-CELLULAR CALCIUM SIGNALING IS PRESENT IN ALL TYPES OF CELLS AND BODY TISSUES. IN THE HUMAN BRAIN, CALCIUM CURRENTS AND WAVES ARE RELATED TO MENTAL ACTIVITIES, INCLUDING EMOTIONS. WE PRESENT A THEORETICAL INTERPRETATION OF THESE PHENOMENA SUGGESTING THEIR INVOLVEMENT IN CHRONIC EMOTIONAL PATTERNS AND IN THE PATHOLOGY OF CANCER. RECENT DEVELOPMENTS ON BIOPHYSICS, TRANSLATIONAL BIOLOGY AND PSYCHONEUROENDOCRINOIMMUNOLOGY (PNEI) CAN SUPPORT EXPLANATORY HYPOTHESES ABOUT THE LINK BETWEEN EMOTIONAL STRESSES AND THE ORIGIN AND DEVELOPMENT OF DIFFERENT TYPES OF TUMOR CELLS. CHRONIC STRESSES MAY CAUSE PERTURBATIONS OF RHYTHMS OF THE PNEI SYSTEM, EXCESSIVE ACTIVATION OF HPA AXIS AND ABNORMAL ACTIVATION OF CALCIUM SIGNALS IN SOMATIC TISSUES, WITH DELETERIOUS EFFECTS ON DIFFERENT PARTS OF THE BODY. THE INCREASING OF CALCIUM SIGNALING INSIDE CELLS MAY LEAD TO A DEREGULATION OF DIFFERENT PATHWAYS AND EPIGENETIC SYSTEMS THAT PROMOTE THE PRODUCTION OF GENOMIC MUTATIONS IN A SECOND PHASE. IN PARTICULAR, THE HYPERACTIVATION OF THE TRANSCRIPTION NUCLEAR FACTOR KAPPAB (NF-KAPPAB), IF IS NOT COUNTERBALANCED BY THE FOLLOWING ACTIVATION OF THE NUCLEAR FACTOR (ERYTHROID-DERIVED 2)-LIKE 2 (NFE2L2 OR NRF2), INCREASES THE PRODUCTION OF OXIDATIVE CATABOLITES, AS THE ADVANCED GLYCATION END PRODUCTS (AGE), WHICH PLAY A KEY ROLE IN THE PROGRESSION OF DIFFERENT TYPES OF CANCER AND OTHER DEGENERATIVE DISEASES. CORTISOL BINDING TO GLUCOCORTICOID RECEPTOR (GR) REDUCES THE ACTIVITY OF BOTH NF-KAPPAB AND NRF2 INSIDE THE CELLS BUT INHIBITS THE CELLULAR IMMUNITY AND THE ANABOLIC PROCESSES OF TISSUE REGENERATION. THE TISSUE ATROPHY AND THE DEFECTIVE ANTI-AGEING MECHANISMS PROMOTES THE TUMORAL CELLS GROWTH AND THEIR ESCAPE FROM THE IMMUNE-SURVEILLANCE. 2017 19 797 37 CELLULAR SENESCENCE IN OSTEOARTHRITIS PATHOLOGY. CELLULAR SENESCENCE IS A STATE OF STABLE PROLIFERATION ARREST OF CELLS. THE SENESCENCE PATHWAY HAS MANY BENEFICIAL EFFECTS AND IS SEEN TO BE ACTIVATED IN DAMAGED/STRESSED CELLS, AS WELL AS DURING EMBRYONIC DEVELOPMENT AND WOUND HEALING. HOWEVER, THE PERSISTENCE AND ACCUMULATION OF SENESCENT CELLS IN VARIOUS TISSUES CAN ALSO IMPAIR FUNCTION AND HAVE BEEN IMPLICATED IN THE PATHOGENESIS OF MANY AGE-RELATED DISEASES. OSTEOARTHRITIS (OA), A SEVERELY DEBILITATING CHRONIC CONDITION CHARACTERIZED BY PROGRESSIVE TISSUE REMODELING AND LOSS OF JOINT FUNCTION, IS THE MOST PREVALENT DISEASE OF THE SYNOVIAL JOINTS, AND INCREASING AGE IS THE PRIMARY OA RISK FACTOR. THE PROFILE OF INFLAMMATORY AND CATABOLIC MEDIATORS PRESENT DURING THE PATHOGENESIS OF OA IS STRIKINGLY SIMILAR TO THE SECRETORY PROFILE OBSERVED IN 'CLASSICAL' SENESCENT CELLS. DURING OA, CHONDROCYTES (THE SOLE CELL TYPE PRESENT WITHIN ARTICULAR CARTILAGE) EXHIBIT INCREASED LEVELS OF VARIOUS SENESCENCE MARKERS, SUCH AS SENESCENCE-ASSOCIATED BETA-GALACTOSIDASE (SABETAGAL) ACTIVITY, TELOMERE ATTRITION, AND ACCUMULATION OF P16INK4A. THIS SUGGESTS THE HYPOTHESIS THAT SENESCENCE OF CELLS WITHIN JOINT TISSUES MAY PLAY A PATHOLOGICAL ROLE IN THE CAUSATION OF OA. IN THIS REVIEW, WE DISCUSS THE MECHANISMS BY WHICH SENESCENT CELLS MAY PREDISPOSE SYNOVIAL JOINTS TO THE DEVELOPMENT AND/OR PROGRESSION OF OA, AS WELL AS TOUCHING UPON VARIOUS EPIGENETIC ALTERATIONS ASSOCIATED WITH BOTH OA AND SENESCENCE. 2017 20 5560 27 ROLE OF HISTONE DEACETYLASE 2 IN EPIGENETICS AND CELLULAR SENESCENCE: IMPLICATIONS IN LUNG INFLAMMAGING AND COPD. HISTONE DEACETYLASE 2 (HDAC2) IS A CLASS I HISTONE DEACETYLASE THAT REGULATES VARIOUS CELLULAR PROCESSES, SUCH AS CELL CYCLE, SENESCENCE, PROLIFERATION, DIFFERENTIATION, DEVELOPMENT, APOPTOSIS, AND GLUCOCORTICOID FUNCTION IN INHIBITING INFLAMMATORY RESPONSE. HDAC2 HAS BEEN SHOWN TO PROTECT AGAINST DNA DAMAGE RESPONSE AND CELLULAR SENESCENCE/PREMATURE AGING VIA AN EPIGENETIC MECHANISM IN RESPONSE TO OXIDATIVE STRESS. THESE PHENOMENA ARE OBSERVED IN PATIENTS WITH CHRONIC OBSTRUCTIVE PULMONARY DISEASE (COPD). HDAC2 IS POSTTRANSLATIONALLY MODIFIED BY OXIDATIVE/CARBONYL STRESS IMPOSED BY CIGARETTE SMOKE AND OXIDANTS, LEADING TO ITS REDUCTION VIA AN UBIQUITINATION-PROTEASOME DEPENDENT DEGRADATION IN LUNGS OF PATIENTS WITH COPD. IN THIS PERSPECTIVE, WE HAVE DISCUSSED THE ROLE OF HDAC2 POSTTRANSLATIONAL MODIFICATIONS AND ITS ROLE IN REGULATION OF INFLAMMATION, HISTONE/DNA EPIGENETIC MODIFICATIONS, DNA DAMAGE RESPONSE, AND CELLULAR SENESCENCE, PARTICULARLY IN INFLAMMAGING, AND DURING THE DEVELOPMENT OF COPD. WE HAVE ALSO DISCUSSED THE POTENTIAL DIRECTIONS FOR FUTURE TRANSLATIONAL RESEARCH AVENUES IN MODULATING LUNG INFLAMMAGING AND CELLULAR SENESCENCE BASED ON EPIGENETIC CHROMATIN MODIFICATIONS IN DISEASES ASSOCIATED WITH INCREASED OXIDATIVE STRESS. 2012