1 5140 106 POTENTIAL REGULATORS OF THE SENESCENCE-ASSOCIATED SECRETORY PHENOTYPE DURING SENESCENCE AND AGING. SENESCENT CELLS EXPRESS AND SECRETE A VARIETY OF EXTRACELLULAR MODULATORS THAT INCLUDE CYTOKINES, CHEMOKINES, PROTEASES, GROWTH FACTORS, AND SOME ENZYMES ASSOCIATED WITH EXTRACELLULAR MATRIX REMODELING, DEFINED AS THE SENESCENCE-ASSOCIATED SECRETORY PHENOTYPE (SASP). SASP REINFORCES SENESCENT CELL CYCLE ARREST, STIMULATES AND RECRUITS IMMUNE CELLS FOR IMMUNE-MEDIATED CLEARANCE OF POTENTIALLY TUMORIGENIC CELLS, LIMITS OR INDUCES FIBROSIS, AND PROMOTES WOUND HEALING AND TISSUE REGENERATION. ON THE OTHER HAND, SASP MEDIATES CHRONIC INFLAMMATION LEADING TO THE DESTRUCTION OF TISSUE STRUCTURE AND FUNCTION AND STIMULATING THE GROWTH AND SURVIVAL OF TUMOR CELLS. SASP IS HIGHLY HETEROGENEOUS AND THE ROLE OF SASP DEPENDS ON THE CONTEXT. THE REGULATION OF SASP OCCURS AT MULTIPLE LEVELS INCLUDING CHROMATIN REMODELING, TRANSCRIPTION, MRNA TRANSLATION, INTRACELLULAR TRAFFICKING, AND SECRETION. SEVERAL SASP MODULATORS HAVE ALREADY BEEN IDENTIFIED SETTING THE STAGE FOR FUTURE RESEARCH ON THEIR CLINICAL APPLICATIONS. IN THIS REVIEW, WE SUMMARIZE IN DETAIL THE POTENTIAL SIGNALING PATHWAYS THAT TRIGGER AND REGULATE SASP PRODUCTION DURING AGING AND SENESCENCE. 2022 2 1894 30 ENDOTHELIAL CELL SENESCENCE AND INFLAMMAGING: MICRORNAS AS BIOMARKERS AND INNOVATIVE THERAPEUTIC TOOLS. AGING IS ACCOMPANIED BY A PROGRESSIVE DECLINE OF ENDOTHELIAL FUNCTION AND A PROGRESSIVE DRIFT TOWARD A SYSTEMIC PRO-INFLAMMATORY STATUS THAT HAS BEEN DESIGNATED "INFLAMMAGING". BOTH PHENOMENA ARE ACCELERATED AND EXACERBATED IN PATIENTS WITH THE MOST COMMON AGE-RELATED DISEASES (ARDS), INCLUDING CANCER. THE FINDING THAT CHRONIC CELL STRESS ACTIVATES A PRO-INFLAMMATORY PROGRAM LEADING TO ACQUISITION OF THE SENESCENCE-ASSOCIATED SECRETORY PHENOTYPE (SASP) AND TO THE PROPAGATION OF SENESCENCE TO SURROUNDING CELLS THROUGH THE SECRETOME, SUGGESTS THAT CELL SENESCENCE MAY HAVE A ROLE IN BOTH PROCESSES. HERE WE: I) DESCRIBE THE ROLE OF CELL SENESCENCE IN ENDOTHELIAL DYSFUNCTION, II) EMPHASIZE THE CONTRIBUTION OF THE ENDOTHELIAL CELL SASP TO INFLAMMAGING, AND III) SUGGEST THAT SELECTIVE REMOVAL OF SENESCENT ENDOTHELIAL CELLS MAY NOT ONLY HINDER SUCH HARMFUL PROCESSES, BUT ALSO REDUCE THE RISK OF DEVELOPING ARDS AND THEIR COMPLICATIONS. ALTHOUGH IN VIVO DETECTION AND TARGETING OF SENESCENT ENDOTHELIAL CELLS ARE STILL BEING INVESTIGATED, IT IS LIKELY THAT THERAPEUTIC STRATEGIES BASED ON ANTIOXIDANT AND ANTI-INFLAMMATORY COMPOUNDS WOULD INVOLVE GENERALIZED ANTI-AGING EFFECTS ALSO BENEFITING ENDOTHELIAL CELLS. MICRORNA (MIRNAS) - SINGLE-STRANDED, NON-CODING RNAS EXPRESSED BY ALL LIVING CELLS AND INVOLVED IN THE EPIGENETIC MODULATION OF ALL TRANSCRIPTIONAL PROGRAMS - MAY CONSTITUTE AN INNOVATIVE, VALUABLE TOOL TO DETECT AND TARGET SENESCENT ENDOTHELIAL CELLS AND TO DEVISE TREATMENTS THAT CAN SLOW DOWN THE PRO-INFLAMMATORY PROGRAM ACTIVATED IN SENESCENT ENDOTHELIAL CELLS. 2016 3 5632 29 SENESCENT CELLS: SASPECTED DRIVERS OF AGE-RELATED PATHOLOGIES. THE PROGRESSION OF PHYSIOLOGICAL AGEING IS DRIVEN BY INTRACELLULAR ABERRATIONS INCLUDING TELOMERE ATTRITION, GENOMIC INSTABILITY, EPIGENETIC ALTERATIONS AND LOSS OF PROTEOSTASIS. THESE IN TURN DAMAGE CELLS AND COMPROMISE THEIR FUNCTIONALITY. CELLULAR SENESCENCE, A STABLE IRREVERSIBLE CELL-CYCLE ARREST, IS ELICITED IN DAMAGED CELLS AND PREVENTS THEIR PROPAGATION IN THE ORGANISM. UNDER NORMAL CONDITIONS, SENESCENT CELLS RECRUIT THE IMMUNE SYSTEM WHICH FACILITATES THEIR REMOVAL FROM TISSUES. NEVERTHELESS, DURING AGEING, TISSUE-RESIDING SENESCENT CELLS TEND TO ACCUMULATE, AND MIGHT NEGATIVELY IMPACT THEIR MICROENVIRONMENT VIA PROFOUND SECRETORY PHENOTYPE WITH PRO-INFLAMMATORY CHARACTERISTICS, TERMED SENESCENCE-ASSOCIATED SECRETORY PHENOTYPE (SASP). INDEED, SENESCENT CELLS ARE MOSTLY ABUNDANT AT SITES OF AGE-RELATED PATHOLOGIES, INCLUDING DEGENERATIVE DISORDERS AND MALIGNANCIES. INTERESTINGLY, STUDIES ON PROGEROID MICE INDICATE THAT SELECTIVE ELIMINATION OF SENESCENT CELLS CAN DELAY AGE-RELATED DETERIORATION. THIS SUGGESTS THAT CHRONIC INFLAMMATION INDUCED BY SENESCENT CELLS MIGHT BE A MAIN DRIVER OF THESE PATHOLOGIES. IMPORTANTLY, SENESCENT CELLS ACCUMULATE AS A RESULT OF DEFICIENT IMMUNE SURVEILLANCE, AND THEIR REMOVAL IS INCREASED UPON THE USE OF IMMUNE STIMULATORY AGENTS. INSIGHTS INTO MECHANISMS OF SENESCENCE SURVEILLANCE COULD BE COMBINED WITH CURRENT APPROACHES FOR CANCER IMMUNOTHERAPY TO PROPOSE NEW PREVENTIVE AND THERAPEUTIC STRATEGIES FOR AGE-RELATED DISEASES. 2014 4 3550 38 IMMUNOSENESCENCE IN ATHEROSCLEROSIS: A ROLE FOR CHRONIC VIRAL INFECTIONS. IMMUNE SYSTEM IS A VERSATILE AND DYNAMIC BODY ORGAN WHICH OFFERS SURVIVAL AND ENDURANCE OF HUMAN BEINGS IN THEIR HOSTILE LIVING ENVIRONMENT. HOWEVER, SIMILAR TO OTHER CELLS, IMMUNE CELLS ARE HIJACKED BY SENESCENCE. THE AGEING IMMUNE CELLS LOSE THEIR BENEFICIAL FUNCTIONS BUT CONTINUE TO PRODUCE INFLAMMATORY MEDIATORS WHICH DRAW OTHER IMMUNE AND NON-IMMUNE CELLS TO THE SENESCENCE LOOP. IMMUNOSENESCENCE HAS BEEN SHOWN TO BE ASSOCIATED WITH DIFFERENT PATHOLOGICAL CONDITIONS AND DISEASES, AMONG WHICH ATHEROSCLEROSIS HAS RECENTLY COME TO LIGHT. THERE ARE COMMON DRIVERS OF BOTH IMMUNOSENESCENCE AND ATHEROSCLEROSIS; E.G. INFLAMMATION, REACTIVE OXYGEN SPECIES (ROS), CHRONIC VIRAL INFECTIONS, GENOMIC DAMAGE, OXIDIZED-LDL, HYPERTENSION, CIGARETTE SMOKE, HYPERGLYCAEMIA, AND MITOCHONDRIAL FAILURE. CHRONIC VIRAL INFECTIONS INDUCE INFLAMMAGING, SUSTAINED CYTOKINE SIGNALING, ROS GENERATION AND DNA DAMAGE WHICH ARE ASSOCIATED WITH ATHEROGENESIS. ACCUMULATING EVIDENCE SHOWS THAT SEVERAL DNA AND RNA VIRUSES ARE STIMULATORS OF IMMUNOSENESCENCE AND ATHEROSCLEROSIS IN AN INTERRELATED NETWORK. DNA VIRUSES SUCH AS CMV, EBV AND HBV UPREGULATE P16, P21 AND P53 SENESCENCE-ASSOCIATED MOLECULES; INDUCE INFLAMMAGING, METABOLIC REPROGRAMMING OF INFECTED CELLS, REPLICATIVE SENESCENCE AND TELOMERE SHORTENING. RNA VIRUSES SUCH AS HCV AND HIV INDUCE ROS GENERATION, DNA DAMAGE, INDUCTION OF SENESCENCE-ASSOCIATED SECRETORY PHENOTYPE (SASP), METABOLIC REPROGRAMMING OF INFECTED CELLS, G1 CELL CYCLE ARREST, TELOMERE SHORTENING, AS WELL AS EPIGENETIC MODIFICATIONS OF DNA AND HISTONES. THE NEWLY EMERGED SARS-COV-2 VIRUS IS ALSO A POTENT INDUCER OF CYTOKINE STORM AND SASP. THE SPIKE PROTEIN OF SARS-COV-2 PROMOTES SENESCENCE PHENOTYPE IN ENDOTHELIAL CELLS BY AUGMENTING P16, P21, SENESCENCE-ASSOCIATED BETA-GALACTOSIDASE (SA-BETA-GAL) AND ADHESION MOLECULES EXPRESSION. THE IMPACT OF SARS-COV-2 MEGA-INFLAMMATION ON ATHEROGENESIS, HOWEVER, REMAINS TO BE INVESTIGATED. IN THIS REVIEW WE FOCUS ON THE COMMON PROCESSES IN IMMUNOSENESCENCE AND ATHEROGENESIS CAUSED BY CHRONIC VIRAL INFECTIONS AND DISCUSS THE CURRENT KNOWLEDGE ON THIS TOPIC. 2022 5 797 31 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 6 798 33 CELLULAR SENESCENCE, SENESCENCE-ASSOCIATED SECRETORY PHENOTYPE, AND CHRONIC KIDNEY DISEASE. CHRONIC KIDNEY DISEASE (CKD) IS INCREASINGLY BEING ACCEPTED AS A TYPE OF RENAL AGEING. THE KIDNEY UNDERGOES AGE-RELATED ALTERATIONS IN BOTH STRUCTURE AND FUNCTION. TO DATE, A COMPREHENSIVE ANALYSIS OF CELLULAR SENESCENCE AND SENESCENCE-ASSOCIATED SECRETORY PHENOTYPE (SASP) IN CKD IS LACKING. HENCE, THIS REVIEW MAINLY DISCUSSES THE RELATIONSHIP BETWEEN THE TWO PHENOMENA TO SHOW THE STRIKING SIMILARITIES BETWEEN SASP AND CKD-ASSOCIATED SECRETORY PHENOTYPE (CASP). IT HAS BEEN REPORTED THAT REPLICATIVE SENESCENCE, STRESS-INDUCED PREMATURE AGEING, AND EPIGENETIC ABNORMALITIES PARTICIPATE IN THE OCCURRENCE AND DEVELOPMENT OF CKD. GENOMIC DAMAGE AND EXTERNAL ENVIRONMENTAL STIMULI CAUSE INCREASED LEVELS OF OXIDATIVE STRESS AND A CHRONIC INFLAMMATORY STATE AS A RESULT OF IRREVERSIBLE CELL CYCLE ARREST AND LOW DOSES OF SASP. SIMILAR TO SASP, CASP FACTORS ACTIVATE TISSUE REPAIR BY MULTIPLE MECHANISMS. ONCE TISSUE REPAIR FAILS, THE ACCUMULATED SASP OR CASP SPECIES AGGRAVATE DNA DAMAGE RESPONSE (DDR) AND CAUSE THE SENESCENT CELLS TO SECRETE MORE SASP FACTORS, ACCELERATING THE PROCESS OF CELLULAR AGEING AND EVENTUALLY LEADING TO VARIOUS AGEING-RELATED CHANGES. IT IS CONCLUDED THAT CELLULAR SENESCENCE AND SASP PARTICIPATE IN THE PATHOLOGICAL PROCESS OF CKD, AND CORRESPONDINGLY CKD ACCELERATED THE PROGRESSION OF CELL SENESCENCE AND THE SECRETION OF SASP. THESE RESULTS WILL FACILITATE THE INTEGRATION OF THESE MECHANISMS INTO THE CARE AND MANAGEMENT OF CKD AND OTHER AGE-RELATED DISEASES. 2017 7 5801 30 STIFFNESS AND AGING IN CARDIOVASCULAR DISEASES: THE DANGEROUS RELATIONSHIP BETWEEN FORCE AND SENESCENCE. BIOLOGICAL AGING IS A PROCESS ASSOCIATED WITH A GRADUAL DECLINE IN TISSUES' HOMEOSTASIS BASED ON THE PROGRESSIVE INABILITY OF THE CELLS TO SELF-RENEW. CELLULAR SENESCENCE IS ONE OF THE HALLMARKS OF THE AGING PROCESS, CHARACTERIZED BY AN IRREVERSIBLE CELL CYCLE ARREST DUE TO REACTIVE OXYGEN SPECIES (ROS) PRODUCTION, TELOMERES SHORTENING, CHRONIC INFLAMMATORY ACTIVATION, AND CHROMATIN MODIFICATIONS. IN THIS REVIEW, WE WILL DESCRIBE THE EFFECTS OF SENESCENCE ON TISSUE STRUCTURE, EXTRACELLULAR MATRIX (ECM) ORGANIZATION, AND NUCLEUS ARCHITECTURE, AND SEE HOW THESE CHANGES AFFECT (ARE AFFECTED BY) MECHANO-TRANSDUCTION. IN OUR VIEW, THIS IS ESSENTIAL FOR A DEEPER UNDERSTANDING OF THE PROGRESSIVE PATHOLOGICAL EVOLUTION OF THE CARDIOVASCULAR SYSTEM AND ITS RELATIONSHIP WITH THE DETRIMENTAL EFFECTS OF RISK FACTORS, KNOWN TO ACT AT AN EPIGENETIC LEVEL. 2021 8 3551 31 IMMUNOSENESCENCE: MOLECULAR MECHANISMS AND DISEASES. INFECTION SUSCEPTIBILITY, POOR VACCINATION EFFICACY, AGE-RELATED DISEASE ONSET, AND NEOPLASMS ARE LINKED TO INNATE AND ADAPTIVE IMMUNE DYSFUNCTION THAT ACCOMPANIES AGING (KNOWN AS IMMUNOSENESCENCE). DURING AGING, ORGANISMS TEND TO DEVELOP A CHARACTERISTIC INFLAMMATORY STATE THAT EXPRESSES HIGH LEVELS OF PRO-INFLAMMATORY MARKERS, TERMED INFLAMMAGING. THIS CHRONIC INFLAMMATION IS A TYPICAL PHENOMENON LINKED TO IMMUNOSENESCENCE AND IT IS CONSIDERED THE MAJOR RISK FACTOR FOR AGE-RELATED DISEASES. THYMIC INVOLUTION, NAIVE/MEMORY CELL RATIO IMBALANCE, DYSREGULATED METABOLISM, AND EPIGENETIC ALTERATIONS ARE STRIKING FEATURES OF IMMUNOSENESCENCE. DISTURBED T-CELL POOLS AND CHRONIC ANTIGEN STIMULATION MEDIATE PREMATURE SENESCENCE OF IMMUNE CELLS, AND SENESCENT IMMUNE CELLS DEVELOP A PROINFLAMMATORY SENESCENCE-ASSOCIATED SECRETORY PHENOTYPE THAT EXACERBATES INFLAMMAGING. ALTHOUGH THE UNDERLYING MOLECULAR MECHANISMS REMAIN TO BE ADDRESSED, IT IS WELL DOCUMENTED THAT SENESCENT T CELLS AND INFLAMMAGING MIGHT BE MAJOR DRIVING FORCES IN IMMUNOSENESCENCE. POTENTIAL COUNTERACTIVE MEASURES WILL BE DISCUSSED, INCLUDING INTERVENTION OF CELLULAR SENESCENCE AND METABOLIC-EPIGENETIC AXES TO MITIGATE IMMUNOSENESCENCE. IN RECENT YEARS, IMMUNOSENESCENCE HAS ATTRACTED INCREASING ATTENTION FOR ITS ROLE IN TUMOR DEVELOPMENT. AS A RESULT OF THE LIMITED PARTICIPATION OF ELDERLY PATIENTS, THE IMPACT OF IMMUNOSENESCENCE ON CANCER IMMUNOTHERAPY IS UNCLEAR. DESPITE SOME SURPRISING RESULTS FROM CLINICAL TRIALS AND DRUGS, IT IS NECESSARY TO INVESTIGATE THE ROLE OF IMMUNOSENESCENCE IN CANCER AND OTHER AGE-RELATED DISEASES. 2023 9 4953 38 PATHOGENESIS OF CHRONIC OBSTRUCTIVE PULMONARY DISEASE (COPD) INDUCED BY CIGARETTE SMOKE. CHRONIC OBSTRUCTIVE PULMONARY DISEASE (COPD) IS A COMMON RESPIRATORY DISEASE THAT IS CHARACTERIZED BY FUNCTIONAL AND STRUCTURAL ALTERATIONS PRIMARILY CAUSED BY LONG-TERM INHALATION OF HARMFUL PARTICLES. CIGARETTE SMOKE (CS) INDUCES AIRWAY INFLAMMATION IN COPD, WHICH IS KNOWN TO PERSIST EVEN AFTER SMOKING CESSATION. THIS REVIEW DISCUSSES THE BASIC PATHOGENESIS OF COPD, WITH PARTICULAR FOCUS ON AN ENDOGENOUS PROTECTIVE MECHANISM AGAINST OXIDATIVE STRESS VIA NRF2, ALTERED IMMUNE RESPONSE OF THE AIRWAY INFLAMMATORY CELLS, EXAGGERATED CELLULAR SENESCENCE OF THE LUNG STRUCTURAL CELLS, AND CELL DEATH WITH EXPANDED INFLAMMATION. RECENTLY, CS-INDUCED MITOCHONDRIA AUTOPHAGY IS REPORTED TO INITIATE PROGRAMMED NECROSIS (NECROPTOSIS). NECROPTOSIS IS A NEW CONCEPT OF CELL DEATH WHICH IS DRIVEN BY A DEFINED MOLECULAR PATHWAY ALONG WITH EXAGGERATED INFLAMMATION. THIS NEW CELL DEATH MECHANISM IS OF IMPORTANCE DUE TO ITS ABILITY TO PRODUCE MORE INFLAMMATORY SUBSTANCES DURING THE PROCESS OF EPITHELIAL DEATH, CONTRIBUTING TO PERSISTENT AIRWAY INFLAMMATION THAT CANNOT BE EXPLAINED BY APOPTOSIS-DERIVED CELL DEATH. AUTOPHAGY IS AN AUTO-CELL COMPONENT DEGRADATION SYSTEM EXECUTED BY LYSOSOMES THAT CONTROLS PROTEIN AND ORGANELLE DEGRADATION FOR SUCCESSFUL HOMEOSTASIS. AS WELL AS IN THE PROCESS OF NECROPTOSIS, AUTOPHAGY IS ALSO OBSERVED DURING CELLULAR SENESCENCE. AGING OF THE LUNGS RESULTS IN THE ACQUISITION OF SENESCENCE-ASSOCIATED SECRETORY PHENOTYPES (SASP) THAT ARE KNOWN TO SECRETE INFLAMMATORY CYTOKINES, CHEMOKINES, GROWTH FACTORS, AND MATRIX METALLOPROTEINASES RESULTING IN CHRONIC LOW-GRADE INFLAMMATION. IN FUTURE RESEARCH, WE INTEND TO HIGHLIGHT THE GENETIC AND EPIGENETIC APPROACHES THAT CAN FACILITATE THE UNDERSTANDING OF DISEASE SUSCEPTIBILITY. THE GOAL OF PRECISION MEDICINE IS TO ESTABLISH MORE ACCURATE DIAGNOSIS AND TREATMENT METHODS BASED ON THE PATIENT-SPECIFIC PATHOGENIC CHARACTERISTICS. THIS REVIEW PROVIDES INSIGHTS INTO CS-INDUCED COPD PATHOGENESIS, WHICH CONTRIBUTES TO A VERY COMPLEX DISEASE. INVESTIGATING THE MECHANISM OF DEVELOPING COPD, ALONG WITH THE AVAILABILITY OF THE PARTICULAR INHIBITORS, WILL LEAD TO NEW THERAPEUTIC APPROACHES IN COPD TREATMENT. 2019 10 1874 37 EMERGING ROLE OF NF-KAPPAB SIGNALING IN THE INDUCTION OF SENESCENCE-ASSOCIATED SECRETORY PHENOTYPE (SASP). THE MAJOR HALLMARK OF CELLULAR SENESCENCE IS AN IRREVERSIBLE CELL CYCLE ARREST AND THUS IT IS A POTENT TUMOR SUPPRESSOR MECHANISM. GENOTOXIC INSULTS, E.G. OXIDATIVE STRESS, ARE IMPORTANT INDUCERS OF THE SENESCENT PHENOTYPE WHICH IS CHARACTERIZED BY AN ACCUMULATION OF SENESCENCE-ASSOCIATED HETEROCHROMATIC FOCI (SAHF) AND DNA SEGMENTS WITH CHROMATIN ALTERATIONS REINFORCING SENESCENCE (DNA-SCARS). INTERESTINGLY, SENESCENT CELLS SECRETE PRO-INFLAMMATORY FACTORS AND THUS THE CONDITION HAS BEEN CALLED THE SENESCENCE-ASSOCIATED SECRETORY PHENOTYPE (SASP). EMERGING DATA HAS REVEALED THAT NF-KAPPAB SIGNALING IS THE MAJOR SIGNALING PATHWAY WHICH STIMULATES THE APPEARANCE OF SASP. IT IS KNOWN THAT DNA DAMAGE PROVOKES NF-KAPPAB SIGNALING VIA A VARIETY OF SIGNALING COMPLEXES CONTAINING NEMO PROTEIN, AN NF-KAPPAB ESSENTIAL MODIFIER, AS WELL AS VIA THE ACTIVATION OF SIGNALING PATHWAYS OF P38MAPK AND RIG-1, RETINOIC ACID INDUCIBLE GENE-1. GENOMIC INSTABILITY EVOKED BY CELLULAR STRESS TRIGGERS EPIGENETIC CHANGES, E.G. RELEASE OF HMGB1 PROTEINS WHICH ARE ALSO POTENT ENHANCERS OF INFLAMMATORY RESPONSES. MOREOVER, ENVIRONMENTAL STRESS AND CHRONIC INFLAMMATION CAN STIMULATE P38MAPK AND CERAMIDE SIGNALING AND INDUCE CELLULAR SENESCENCE WITH PRO-INFLAMMATORY RESPONSES. ON THE OTHER HAND, TWO CYCLIN-DEPENDENT KINASE INHIBITORS, P16INK4A AND P14ARF, ARE EFFECTIVE INHIBITORS OF NF-KAPPAB SIGNALING. WE WILL REVIEW IN DETAIL THE SIGNALING PATHWAYS WHICH ACTIVATE NF-KAPPAB SIGNALING AND TRIGGER SASP IN SENESCENT CELLS. 2012 11 5322 20 PULMONARY DISEASES AND AGEING. CHRONIC OBSTRUCTIVE PULMONARY DISEASE (COPD) AND IDIOPATHIC PULMONARY FIBROSIS ARE REGARDED AS A DISEASES OF ACCELERATED LUNG AGEING AND SHOW ALL OF THE HALLMARKS OF AGEING, INCLUDING TELOMERE SHORTENING, CELLULAR SENESCENCE, ACTIVATION OF PI3 KINASE-MTOR SIGNALING, IMPAIRED AUTOPHAGY, MITOCHONDRIAL DYSFUNCTION, STEM CELL EXHAUSTION, EPIGENETIC CHANGES, ABNORMAL MICRORNA PROFILES, IMMUNOSENESCENCE AND A LOW GRADE CHRONIC INFLAMMATION DUE TO SENESCENCE-ASSOCIATED SECRETORY PHENOTYPE (SASP). MANY OF THESE AGEING MECHANISMS ARE DRIVEN BY EXOGENOUS AND ENDOGENOUS OXIDATIVE STRESS. THERE IS ALSO A REDUCTION IN ANTI-AGEING MOLECULES, SUCH AS SIRTUINS AND KLOTHO, WHICH FURTHER ACCELERATE THE AGEING PROCESS. UNDERSTANDING THESE MOLECULAR MECHANISMS HAS IDENTIFIED SEVERAL NOVEL THERAPEUTIC TARGETS AND SEVERAL DRUGS AND DIETARY INTERVENTIONS ARE NOW IN DEVELOPMENT TO TREAT CHRONIC LUNG DISEASE. 2019 12 4738 38 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 13 4037 23 MACROPHAGE IMMUNOMETABOLISM AND INFLAMMAGING: ROLES OF MITOCHONDRIAL DYSFUNCTION, CELLULAR SENESCENCE, CD38, AND NAD. AGING IS A COMPLEX PROCESS THAT INVOLVES DYSFUNCTION ON MULTIPLE LEVELS, ALL OF WHICH SEEM TO CONVERGE ON INFLAMMATION. MACROPHAGES ARE INTIMATELY INVOLVED IN INITIATING AND RESOLVING INFLAMMATION, AND THEIR DYSREGULATION WITH AGE IS A PRIMARY CONTRIBUTOR TO INFLAMMAGING-A STATE OF CHRONIC, LOW-GRADE INFLAMMATION THAT DEVELOPS DURING AGING. AMONG THE AGE-RELATED CHANGES THAT OCCUR TO MACROPHAGES ARE A HEIGHTENED STATE OF BASAL INFLAMMATION AND DIMINISHED OR HYPERACTIVE INFLAMMATORY RESPONSES, WHICH SEEM TO BE DRIVEN BY METABOLIC-DEPENDENT EPIGENETIC CHANGES. IN THIS REVIEW ARTICLE WE PROVIDE A BRIEF OVERVIEW OF MITOCHONDRIAL FUNCTIONS AND AGE-RELATED CHANGES THAT OCCUR TO MACROPHAGES, WITH AN EMPHASIS ON HOW THE INFLAMMAGING ENVIRONMENT, SENESCENCE, AND NAD DECLINE CAN AFFECT THEIR METABOLISM, PROMOTE DYSREGULATION, AND CONTRIBUTE TO INFLAMMAGING AND AGE-RELATED PATHOLOGIES. 2020 14 5765 30 SOURCE OF CHRONIC INFLAMMATION IN AGING. AGING IS A COMPLEX PROCESS THAT RESULTS FROM A COMBINATION OF ENVIRONMENTAL, GENETIC, AND EPIGENETIC FACTORS. A CHRONIC PRO-INFLAMMATORY STATUS IS A PERVASIVE FEATURE OF AGING. THIS CHRONIC LOW-GRADE INFLAMMATION OCCURRING IN THE ABSENCE OF OVERT INFECTION HAS BEEN DEFINED AS "INFLAMMAGING" AND REPRESENTS A SIGNIFICANT RISK FACTOR FOR MORBIDITY AND MORTALITY IN THE ELDERLY. THE LOW-GRADE INFLAMMATION PERSISTS EVEN AFTER REVERSING PRO-INFLAMMATORY STIMULI SUCH AS LDL CHOLESTEROL AND THE RENIN-ANGIOTENSIN SYSTEM (RAS). RECENTLY, SEVERAL POSSIBLE SOURCES OF CHRONIC LOW-GRADE INFLAMMATION OBSERVED DURING AGING AND AGE-RELATED DISEASES HAVE BEEN PROPOSED. CELL SENESCENCE AND DYSREGULATION OF INNATE IMMUNITY IS ONE SUCH MECHANISM BY WHICH PERSISTENT PROLONGED INFLAMMATION OCCURS EVEN AFTER THE INITIAL STIMULUS HAS BEEN REMOVED. ADDITIONALLY, THE COAGULATION FACTOR THAT ACTIVATES INFLAMMATORY SIGNALING BEYOND ITS ROLE IN THE COAGULATION SYSTEM HAS BEEN IDENTIFIED. THIS SIGNAL COULD BE A NEW SOURCE OF CHRONIC INFLAMMATION AND CELL SENESCENCE. HERE, WE SUMMARIZED THE FACTORS AND CELLULAR PATHWAYS/PROCESSES THAT ARE KNOWN TO REGULATE LOW-GRADE PERSISTENT INFLAMMATION IN AGING AND AGE-RELATED DISEASE. 2018 15 4377 27 MITOCHONDRIAL AGING: FOCUS ON MITOCHONDRIAL DNA DAMAGE IN ATHEROSCLEROSIS - A MINI-REVIEW. ATHEROSCLEROSIS IS A COMPLEX DISEASE WHICH CAN BE DESCRIBED AS AN EXCESSIVE FIBROFATTY, PROLIFERATIVE, INFLAMMATORY RESPONSE TO DAMAGE TO THE ARTERY WALL INVOLVING SEVERAL CELL TYPES SUCH AS SMOOTH MUSCLE CELLS, MONOCYTE-DERIVED MACROPHAGES, LYMPHOCYTES, DENDRITIC CELLS AND PLATELETS. ON THE OTHER HAND, ATHEROSCLEROSIS IS A TYPICAL AGE-RELATED DEGENERATIVE PATHOLOGY, WHICH IS CHARACTERIZED BY SIGNS OF CELL SENESCENCE IN THE ARTERIAL WALL INCLUDING REDUCED CELL PROLIFERATION, IRREVERSIBLE GROWTH ARREST AND APOPTOSIS, INCREASED DNA DAMAGE, THE PRESENCE OF EPIGENETIC MODIFICATIONS, SHORTENING OF TELOMERE LENGTH AND MITOCHONDRIAL DYSFUNCTION. THE MOST PROMINENT CHARACTERISTICS OF MITOCHONDRIAL AGING ARE THEIR STRUCTURAL ALTERATIONS AND MITOCHONDRIAL DNA DAMAGE. THE MECHANISMS OF MITOCHONDRIAL GENOME DAMAGE IN THE DEVELOPMENT OF CHRONIC AGE-RELATED DISEASES SUCH AS ATHEROSCLEROSIS ARE NOT YET WELL UNDERSTOOD. THIS REVIEW FOCUSES ON THE LATEST FINDINGS FROM STUDIES OF THOSE MUTATIONS OF THE MITOCHONDRIAL GENOME WHICH MAY PLAY AN IMPORTANT ROLE IN THE DEVELOPMENT OF ATHEROSCLEROSIS AND WHICH ARE, AT THE SAME TIME, ALSO MARKERS OF MITOCHONDRIAL AGING AND CELL SENESCENCE. 2015 16 1864 35 EMERGING AVENUES LINKING INFLAMMATION AND CANCER. THE ROLE OF INFLAMMATION IN CARCINOGENESIS HAS BEEN EXTENSIVELY INVESTIGATED AND WELL DOCUMENTED. MANY BIOCHEMICAL PROCESSES THAT ARE ALTERED DURING CHRONIC INFLAMMATION HAVE BEEN IMPLICATED IN TUMORIGENESIS. THESE INCLUDE SHIFTING CELLULAR REDOX BALANCE TOWARD OXIDATIVE STRESS; INDUCTION OF GENOMIC INSTABILITY; INCREASED DNA DAMAGE; STIMULATION OF CELL PROLIFERATION, METASTASIS, AND ANGIOGENESIS; DEREGULATION OF CELLULAR EPIGENETIC CONTROL OF GENE EXPRESSION; AND INAPPROPRIATE EPITHELIAL-TO-MESENCHYMAL TRANSITION. A WIDE ARRAY OF PROINFLAMMATORY CYTOKINES, PROSTAGLANDINS, NITRIC OXIDE, AND MATRICELLULAR PROTEINS ARE CLOSELY INVOLVED IN PREMALIGNANT AND MALIGNANT CONVERSION OF CELLS IN A BACKGROUND OF CHRONIC INFLAMMATION. INAPPROPRIATE TRANSCRIPTION OF GENES ENCODING INFLAMMATORY MEDIATORS, SURVIVAL FACTORS, AND ANGIOGENIC AND METASTATIC PROTEINS IS THE KEY MOLECULAR EVENT IN LINKING INFLAMMATION AND CANCER. ABERRANT CELL SIGNALING PATHWAYS COMPRISING VARIOUS KINASES AND THEIR DOWNSTREAM TRANSCRIPTION FACTORS HAVE BEEN IDENTIFIED AS THE MAJOR CONTRIBUTORS IN ABNORMAL GENE EXPRESSION ASSOCIATED WITH INFLAMMATION-DRIVEN CARCINOGENESIS. THE POSTTRANSCRIPTIONAL REGULATION OF GENE EXPRESSION BY MICRORNAS ALSO PROVIDES THE MOLECULAR BASIS FOR LINKING INFLAMMATION TO CANCER. THIS REVIEW HIGHLIGHTS THE MULTIFACETED ROLE OF INFLAMMATION IN CARCINOGENESIS IN THE CONTEXT OF ALTERED CELLULAR REDOX SIGNALING. 2012 17 5581 28 ROLE OF NF-KAPPAB IN AGEING AND AGE-RELATED DISEASES: LESSONS FROM GENETICALLY MODIFIED MOUSE MODELS. AGEING IS A COMPLEX PROCESS, INDUCED BY MULTIFACETED INTERACTION OF GENETIC, EPIGENETIC, AND ENVIRONMENTAL FACTORS. IT IS MANIFESTED BY A DECLINE IN THE PHYSIOLOGICAL FUNCTIONS OF ORGANISMS AND ASSOCIATED TO THE DEVELOPMENT OF AGE-RELATED CHRONIC DISEASES AND CANCER DEVELOPMENT. IT IS CONSIDERED THAT AGEING FOLLOWS A STRICTLY-REGULATED PROGRAM, IN WHICH SOME SIGNALING PATHWAYS CRITICALLY CONTRIBUTE TO THE ESTABLISHMENT AND MAINTENANCE OF THE AGED STATE. CHRONIC INFLAMMATION IS A MAJOR MECHANISM THAT PROMOTES THE BIOLOGICAL AGEING PROCESS AND COMORBIDITY, WITH THE TRANSCRIPTION FACTOR NF-KAPPAB (NUCLEAR FACTOR KAPPA-LIGHT-CHAIN-ENHANCER OF ACTIVATED B CELLS) AS A CRUCIAL MEDIATOR OF INFLAMMATORY RESPONSES. THIS, TOGETHER WITH THE FINDING THAT THE ACTIVATION OR INHIBITION OF NF-KAPPAB CAN INDUCE OR REVERSE RESPECTIVELY THE MAIN FEATURES OF AGED ORGANISMS, HAS BROUGHT IT UNDER CONSIDERATION AS A KEY TRANSCRIPTION FACTOR THAT ACTS AS A DRIVER OF AGEING. IN THIS REVIEW, WE FOCUSED ON THE DATA OBTAINED ENTIRELY THROUGH THE GENERATION OF KNOCKOUT AND TRANSGENIC MOUSE MODELS OF EITHER PROTEIN INVOLVED IN THE NF-KAPPAB SIGNALING PATHWAY THAT HAVE PROVIDED RELEVANT INFORMATION ABOUT THE INTRICATE PROCESSES OR MOLECULAR MECHANISMS THAT CONTROL AGEING. WE HAVE REVIEWED THE RELATIONSHIP OF NF-KAPPAB AND PREMATURE AGEING; THE DEVELOPMENT OF CANCER ASSOCIATED WITH AGEING AND THE IMPLICATION OF NF-KAPPAB ACTIVATION IN THE DEVELOPMENT OF AGE-RELATED DISEASES, SOME OF WHICH GREATLY INCREASE THE RISK OF DEVELOPING CANCER. 2021 18 6395 38 THE ROLE OF THE MEDIATORS OF INFLAMMATION IN CANCER DEVELOPMENT. EPIGENETIC DISORDERS SUCH AS POINT MUTATIONS IN CELLULAR TUMOR SUPPRESSOR GENES, DNA METHYLATION AND POST-TRANSLATIONAL MODIFICATIONS ARE NEEDED TO TRANSFORMATION OF NORMAL CELLS INTO CANCER CELLS. THESE EVENTS RESULT IN ALTERATIONS IN CRITICAL PATHWAYS RESPONSIBLE FOR MAINTAINING THE NORMAL CELLULAR HOMEOSTASIS, TRIGGERING TO AN INFLAMMATORY RESPONSE WHICH CAN LEAD THE DEVELOPMENT OF CANCER. THE INFLAMMATORY RESPONSE IS A UNIVERSAL DEFENSE MECHANISM ACTIVATED IN RESPONSE TO AN INJURY TISSUE, OF ANY NATURE, THAT INVOLVES BOTH INNATE AND ADAPTIVE IMMUNE RESPONSES, THROUGH THE COLLECTIVE ACTION OF A VARIETY OF SOLUBLE MEDIATORS. MANY INFLAMMATORY SIGNALING PATHWAYS ARE ACTIVATED IN SEVERAL TYPES OF CANCER, LINKING CHRONIC INFLAMMATION TO TUMORIGENESIS PROCESS. THUS, INFLAMMATORY RESPONSES PLAY DECISIVE ROLES AT DIFFERENT STAGES OF TUMOR DEVELOPMENT, INCLUDING INITIATION, PROMOTION, GROWTH, INVASION, AND METASTASIS, AFFECTING ALSO THE IMMUNE SURVEILLANCE. IMMUNE CELLS THAT INFILTRATE TUMORS ENGAGE IN AN EXTENSIVE AND DYNAMIC CROSSTALK WITH CANCER CELLS, AND SOME OF THE MOLECULAR EVENTS THAT MEDIATE THIS DIALOG HAVE BEEN REVEALED. A RANGE OF INFLAMMATION MEDIATORS, INCLUDING CYTOKINES, CHEMOKINES, FREE RADICALS, PROSTAGLANDINS, GROWTH AND TRANSCRIPTION FACTORS, MICRORNAS, AND ENZYMES AS, CYCLOOXYGENASE AND MATRIX METALLOPROTEINASE, COLLECTIVELY ACTS TO CREATE A FAVORABLE MICROENVIRONMENT FOR THE DEVELOPMENT OF TUMORS. IN THIS REVIEW ARE PRESENTED THE MAIN MEDIATORS OF THE INFLAMMATORY RESPONSE AND DISCUSSED THE LIKELY MECHANISMS THROUGH WHICH, THEY INTERACT WITH EACH OTHER TO CREATE A CONDITION FAVORABLE TO DEVELOPMENT OF CANCER. 2015 19 5634 41 SENOLYTICS AND SENOMORPHICS: NATURAL AND SYNTHETIC THERAPEUTICS IN THE TREATMENT OF AGING AND CHRONIC DISEASES. CELLULAR SENESCENCE IS A HETEROGENEOUS PROCESS GUIDED BY GENETIC, EPIGENETIC AND ENVIRONMENTAL FACTORS, CHARACTERIZING MANY TYPES OF SOMATIC CELLS. IT HAS BEEN SUGGESTED AS AN AGING HALLMARK THAT IS BELIEVED TO CONTRIBUTE TO AGING AND CHRONIC DISEASES. SENESCENT CELLS (SC) EXHIBIT A SPECIFIC SENESCENCE-ASSOCIATED SECRETORY PHENOTYPE (SASP), MAINLY CHARACTERIZED BY THE PRODUCTION OF PROINFLAMMATORY AND MATRIX-DEGRADING MOLECULES. WHEN SC ACCUMULATE, A CHRONIC, SYSTEMIC, LOW-GRADE INFLAMMATION, KNOWN AS INFLAMMAGING, IS INDUCED. IN TURN, THIS CHRONIC IMMUNE SYSTEM ACTIVATION RESULTS IN REDUCED SC CLEARANCE THUS ESTABLISHING A VICIOUS CIRCLE THAT FUELS INFLAMMAGING. SC ACCUMULATION REPRESENTS A CAUSAL FACTOR FOR VARIOUS AGE-RELATED PATHOLOGIES. TARGETING OF SEVERAL AGING HALLMARKS HAS BEEN SUGGESTED AS A STRATEGY TO AMELIORATE HEALTHSPAN AND POSSIBLY LIFESPAN. CONSEQUENTLY, SC AND SASP ARE VIEWED AS POTENTIAL THERAPEUTIC TARGETS EITHER THROUGH THE SELECTIVE KILLING OF SC OR THE SELECTIVE SASP BLOCKAGE, THROUGH NATURAL OR SYNTHETIC COMPOUNDS. THESE COMPOUNDS ARE MEMBERS OF A FAMILY OF AGENTS CALLED SENOTHERAPEUTICS DIVIDED INTO SENOLYTICS AND SENOMORPHICS. FEW OF THEM ARE ALREADY IN CLINICAL TRIALS, POSSIBLY REPRESENTING A FUTURE TREATMENT OF AGE-RELATED PATHOLOGIES INCLUDING DISEASES SUCH AS ATHEROSCLEROSIS, OSTEOARTHRITIS, OSTEOPOROSIS, CANCER, DIABETES, NEURODEGENERATIVE DISEASES SUCH AS ALZHEIMER'S DISEASE, CARDIOVASCULAR DISEASES, HEPATIC STEATOSIS, CHRONIC OBSTRUCTIVE PULMONARY DISEASE, IDIOPATHIC PULMONARY FIBROSIS AND AGE-RELATED MACULAR DEGENERATION. IN THIS REVIEW, WE PRESENT THE ALREADY IDENTIFIED SENOLYTICS AND SENOMORPHICS FOCUSING ON THEIR REDOX-SENSITIVE PROPERTIES. WE DESCRIBE THE STUDIES THAT REVEALED THEIR EFFECTS ON CELLULAR SENESCENCE AND ENABLED THEIR NOMINATION AS NOVEL ANTI-AGING AGENTS. WE REFER TO THE SENOLYTICS THAT ARE ALREADY IN CLINICAL TRIALS AND WE PRESENT VARIOUS ADVERSE EFFECTS EXHIBITED BY SENOTHERAPEUTICS SO FAR. FINALLY, WE DISCUSS ASPECTS OF THE SENOTHERAPEUTICS THAT NEED IMPROVEMENT AND WE SUGGEST THE DESIGN OF FUTURE SENOTHERAPEUTICS TO TARGET SPECIFIC REDOX-REGULATED SIGNALING PATHWAYS IMPLICATED EITHER IN THE REGULATION OF SASP OR IN THE ELIMINATION OF SC. 2021 20 5560 34 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