1 5627 100 SELECTIVE TARGETING OF THE STRESS CHAPEROME AS A THERAPEUTIC STRATEGY. NORMAL CELLULAR FUNCTION IS MAINTAINED BY COORDINATED PROTEOME MACHINERY THAT PERFORMS A VAST ARRAY OF ACTIVITIES. HELPING THE PROTEOME IN SUCH ROLES IS THE CHAPEROME, A NETWORK OF MOLECULAR CHAPERONES AND FOLDING ENZYMES. THE STRESSED CELL CONTAINS, AT ANY TIME, A COMPLEX MIXTURE OF CHAPEROME COMPLEXES; A MAJORITY PERFORMS 'HOUSEKEEPING FUNCTIONS' SIMILARLY TO NON-STRESSED, NORMAL CELLS, BUT A FINELY-TUNED FRACTION BUFFERS THE PROTEOME ALTERED BY CHRONIC STRESS. THE STRESS CHAPEROME IS EPIGENETICALLY DISTINCT FROM ITS NORMAL, HOUSEKEEPING COUNTERPART, PROVIDING A BASIS FOR ITS SELECTIVE TARGETING BY SMALL MOLECULES. WE DISCUSS HERE THE DEVELOPMENT OF CHAPEROME INHIBITORS, AND HOW AGENTS TARGETING CHAPEROME MEMBERS IN STRESSED CELLS ARE IN FACT BEING DIRECTED TOWARDS CHAPEROME COMPLEXES, AND THEIR EFFECT IS THEREFORE DETERMINED BY THEIR ABILITY TO SAMPLE AND ENGAGE SUCH COMPLEXES. A NEW APPROACH IS NEEDED TO TARGET AND IMPLEMENT CHAPEROME MODULATORS IN THE INVESTIGATION OF DISEASES, AND WE PROPOSE THAT THE CLASSICAL THINKING IN DRUG DISCOVERY NEEDS ADJUSTMENT WHEN DEVELOPING CHAPEROME-TARGETING DRUGS. 2014 2 450 26 APOPTOSIS AND AGING: INCREASED RESISTANCE TO APOPTOSIS ENHANCES THE AGING PROCESS. APOPTOSIS IS A VITAL COMPONENT IN THE EVOLUTIONARILY CONSERVED HOST DEFENSE SYSTEM. APOPTOSIS IS THE GUARDIAN OF TISSUE INTEGRITY BY REMOVING UNFIT AND INJURED CELLS WITHOUT EVOKING INFLAMMATION. HOWEVER, APOPTOSIS SEEMS TO BE A DOUBLE-EDGED SWORD SINCE DURING LOW-LEVEL CHRONIC STRESS, SUCH AS IN AGING, INCREASED RESISTANCE TO APOPTOSIS CAN LEAD TO THE SURVIVAL OF FUNCTIONALLY DEFICIENT, POST-MITOTIC CELLS WITH DAMAGED HOUSEKEEPING FUNCTIONS. SENESCENT CELLS ARE REMARKABLY RESISTANT TO APOPTOSIS, AND SEVERAL STUDIES INDICATE THAT HOST DEFENSE MECHANISMS CAN ENHANCE ANTI-APOPTOTIC SIGNALING, WHICH SUBSEQUENTLY INDUCES A SENESCENT, PRO-INFLAMMATORY PHENOTYPE DURING THE AGING PROCESS. AT THE MOLECULAR LEVEL, AGE-RELATED RESISTANCE TO APOPTOSIS INVOLVES (1) FUNCTIONAL DEFICIENCY IN P53 NETWORK, (2) INCREASED ACTIVITY IN THE NF-KAPPAB-IAP/JNK AXIS, AND (3) CHANGES IN MOLECULAR CHAPERONES, MICRORNAS, AND EPIGENETIC REGULATION. WE WILL DISCUSS THE MOLECULAR BASIS OF AGE-RELATED RESISTANCE TO APOPTOSIS AND EMPHASIZE THAT INCREASED RESISTANCE COULD ENHANCE THE AGING PROCESS. 2011 3 5396 23 REDUCED HISTONE BIOSYNTHESIS AND CHROMATIN CHANGES ARISING FROM A DAMAGE SIGNAL AT TELOMERES. DURING REPLICATIVE AGING OF PRIMARY CELLS MORPHOLOGICAL TRANSFORMATIONS OCCUR, THE EXPRESSION PATTERN IS ALTERED AND CHROMATIN CHANGES GLOBALLY. HERE WE SHOW THAT CHRONIC DAMAGE SIGNALS, PROBABLY CAUSED BY TELOMERE PROCESSING, AFFECT EXPRESSION OF HISTONES AND LEAD TO THEIR DEPLETION. WE INVESTIGATED THE ABUNDANCE AND CELL CYCLE EXPRESSION OF HISTONES AND HISTONE CHAPERONES AND FOUND DEFECTS IN HISTONE BIOSYNTHESIS DURING REPLICATIVE AGING. SIMULTANEOUSLY, EPIGENETIC MARKS WERE REDISTRIBUTED ACROSS THE PHASES OF THE CELL CYCLE AND THE DNA DAMAGE RESPONSE (DDR) MACHINERY WAS ACTIVATED. THE AGE-DEPENDENT REPROGRAMMING AFFECTED TELOMERIC CHROMATIN ITSELF, WHICH WAS PROGRESSIVELY DESTABILIZED, LEADING TO A BOOST OF THE TELOMERE-ASSOCIATED DDR WITH EACH SUCCESSIVE CELL CYCLE. WE PROPOSE A MECHANISM IN WHICH CHANGES IN THE STRUCTURAL AND EPIGENETIC INTEGRITY OF TELOMERES AFFECT CORE HISTONES AND THEIR CHAPERONES, ENFORCING A SELF-PERPETUATING PATHWAY OF GLOBAL EPIGENETIC CHANGES THAT ULTIMATELY LEADS TO SENESCENCE. 2010 4 127 26 A TRANSCRIPTIONAL PERSPECTIVE ON HUMAN MACROPHAGE BIOLOGY. MACROPHAGES ARE A MAJOR CELL TYPE IN TISSUE HOMEOSTASIS AND CONTRIBUTE TO BOTH PATHOLOGY AND RESOLUTION IN ALL ACUTE AND CHRONIC INFLAMMATORY DISEASES RANGING FROM INFECTIONS, CANCER, OBESITY, ATHEROSCLEROSIS, AUTOIMMUNE DISORDERS TO NEURODEGENERATIVE DISEASES SUCH AS ALZHEIMER'S DISEASE. THE CELLULAR AND FUNCTIONAL DIVERSITY OF MACROPHAGES DEPENDS UPON TIGHTLY REGULATED TRANSCRIPTION. THE INNATE IMMUNE SYSTEM IS UNDER PROFOUND EVOLUTIONARY SELECTION. THERE IS INCREASING RECOGNITION THAT HUMAN MACROPHAGE BIOLOGY DIFFERS VERY SIGNIFICANTLY FROM THAT OF COMMONLY STUDIED ANIMAL MODELS, WHICH THEREFORE CAN HAVE A LIMITED PREDICTIVE VALUE. HERE WE REPORT ON THE NEWEST FINDINGS ON TRANSCRIPTIONAL CONTROL OF MACROPHAGE ACTIVATION, AND HOW WE ENVISION INTEGRATING STUDIES ON TRANSCRIPTIONAL AND EPIGENETIC REGULATION, AND MORE CLASSICAL APPROACHES IN MURINE MODELS. MOREOVER, WE PROVIDE NEW INSIGHTS INTO HOW WE CAN LEARN ABOUT TRANSCRIPTIONAL REGULATION IN THE HUMAN SYSTEM FROM LARGER EFFORTS SUCH AS THE FANTOM (FUNCTIONAL ANNOTATION OF THE MAMMALIAN GENOME) CONSORTIUM. 2015 5 3703 27 INFLAMMATORY SIGNALLING AS MEDIATOR OF EPIGENETIC MODULATION IN TISSUE-SPECIFIC CHRONIC INFLAMMATION. RECENT SUCCESSES OF THERAPEUTIC INTERVENTION IN CHRONIC INFLAMMATORY DISEASES USING EPIGENETIC MODIFIERS SUCH AS HISTONE DEACETYLASE INHIBITORS AND INHIBITORS OF DNA METHYLATION SUGGEST THAT EPIGENETIC REPROGRAMMING PLAYS A ROLE IN THE AETIOLOGY OF THESE DISEASES. THE EPIGENETIC SIGNATURE OF A GIVEN IMMUNE CELL IS REFLECTED IN THE HISTORY OF MODIFICATIONS FROM DIFFERENT SIGNALS THE CELL HAS BEEN SUBJECTED TO DURING DIFFERENTIATION. LIKE OTHER CELLS, DIFFERENTIATING IMMUNE CELLS ARE DEPENDENT ON A COMPLEX COMBINATION OF INTER- AND INTRACELL SIGNALLING AS WELL AS TRANSCRIPTION MACHINERIES TO MODULATE THEIR EPIGENOMES IN ORDER TO MEDIATE DIFFERENTIATION. DESPITE EXTENSIVE RESEARCH INTO THESE PROCESSES, THE LINK BETWEEN CELLULAR SIGNALLING AND EPIGENETIC MODULATION REMAINS POORLY UNDERSTOOD. HERE, WE REVIEW RECENT PROGRESS AND DISCUSS KEY FACTORS DRIVING EPIGENETIC MODULATION IN CHRONIC INFLAMMATION. 2009 6 3123 28 GETTING AN INSIGHT INTO THE COMPLEXITY OF MAJOR CHRONIC INFLAMMATORY AND DEGENERATIVE DISEASES: A POTENTIAL NEW SYSTEMIC APPROACH TO THEIR TREATMENT. AS THE MODERN SOCIETY IS TROUBLED BY MULTI-FACTORIAL DISEASES, RESEARCH HAS BEEN CONDUCTED ON COMPLEX REALITIES INCLUDING CHRONIC INFLAMMATION, CANCER, OBESITY, HIV INFECTION, METABOLIC SYNDROME AND ITS DETRIMENTAL CARDIOVASCULAR COMPLICATIONS AS WELL AS DEPRESSION AND OTHER BRAIN DISORDERS. DETERIORATION OF CRUCIAL HOMEOSTATIC MECHANISMS IN SUCH DISEASES INVARIABLY RESULTS IN ACTIVATION OF INFLAMMATORY MEDIATORS, CHRONIC INFLAMMATION, LOSS IN IMMUNOLOGICAL FUNCTION, INCREASED SUSCEPTIBILITY TO DISEASES, ALTERATION OF METABOLISM, DECREASE OF ENERGY PRODUCTION AND NEURO-COGNITIVE DECLINE. REGULATION OF GENES EXPRESSION BY EPIGENETIC CODE IS THE DOMINANT MECHANISM FOR THE TRANSDUCTION OF ENVIRONMENTAL INPUTS, SUCH AS STRESS AND INFLAMMATION TO LASTING PHYSIOLOGICAL CHANGES. ACUTE AND CHRONIC STRESS DETERMINES DNA METHYLATION AND HISTONE MODIFICATIONS IN BRAIN REGIONS WHICH MAY CONTRIBUTE TO NEURO-DEGENERATIVE DISORDERS. NUCLEAR GLUCOCORTICOIDS RECEPTOR INTERACTS WITH THE EPIGENOMA RESULTING IN A CORTISOL RESISTANCE STATUS ASSOCIATED WITH A DETERIORATION OF THE METABOLIC AND IMMUNE FUNCTIONS. GONADAL STEROIDS RECEPTORS HAVE A SIMILAR CAPACITY TO PRODUCE EPIGENOMIC REORGANIZATION OF CHROMATINE STRUCTURE. EPIGENOMIC-INDUCED REDUCTION IN IMMUNE CELLS TELOMERES LENGTH HAS BEEN OBSERVED IN MANY DEGENERATIVE DISEASES, INCLUDING ALL TYPES OF CANCER. THE FINAL RESULT OF THESE EPIGENETIC ALTERATIONS IS A SERIOUS DAMAGE TO THE NEURO-ENDOCRINE-IMMUNE-METABOLIC ADAPTIVE SYSTEMS. IN THIS STUDY, WE PROPOSE A TREATMENT WITH STEM CELLS DIFFERENTIATION STAGE FACTORS TAKEN FROM ZEBRAFISH EMBRYOS WHICH ARE ABLE TO REGULATE THE GENES EXPRESSION OF NORMAL AND PATHOLOGICAL STEM CELLS IN A DIFFERENT SPECIFIC WAY. 2015 7 2412 35 EPIGENETIC SIDE-EFFECTS OF COMMON PHARMACEUTICALS: A POTENTIAL NEW FIELD IN MEDICINE AND PHARMACOLOGY. THE TERM "EPIGENETICS" REFERS TO DNA AND CHROMATIN MODIFICATIONS THAT PERSIST FROM ONE CELL DIVISION TO THE NEXT, DESPITE A LACK OF CHANGE IN THE UNDERLYING DNA SEQUENCE. THE "EPIGENOME" REFERS TO THE OVERALL EPIGENETIC STATE OF A CELL, AND SERVES AS AN INTERFACE BETWEEN THE ENVIRONMENT AND THE GENOME. THE EPIGENOME IS DYNAMIC AND RESPONSIVE TO ENVIRONMENTAL SIGNALS NOT ONLY DURING DEVELOPMENT, BUT ALSO THROUGHOUT LIFE; AND IT IS BECOMING INCREASINGLY APPARENT THAT CHEMICALS CAN CAUSE CHANGES IN GENE EXPRESSION THAT PERSIST LONG AFTER EXPOSURE HAS CEASED. HERE WE PRESENT THE HYPOTHESIS THAT COMMONLY-USED PHARMACEUTICAL DRUGS CAN CAUSE SUCH PERSISTENT EPIGENETIC CHANGES. DRUGS MAY ALTER EPIGENETIC HOMEOSTASIS BY DIRECT OR INDIRECT MECHANISMS. DIRECT EFFECTS MAY BE CAUSED BY DRUGS WHICH AFFECT CHROMATIN ARCHITECTURE OR DNA METHYLATION. FOR EXAMPLE THE ANTIHYPERTENSIVE HYDRALAZINE INHIBITS DNA METHYLATION. AN EXAMPLE OF AN INDIRECTLY ACTING DRUG IS ISOTRETINOIN, WHICH HAS TRANSCRIPTION FACTOR ACTIVITY. A TWO-TIER MECHANISM IS POSTULATED FOR INDIRECT EFFECTS IN WHICH ACUTE EXPOSURE TO A DRUG INFLUENCES SIGNALING PATHWAYS THAT MAY LEAD TO AN ALTERATION OF TRANSCRIPTION FACTOR ACTIVITY AT GENE PROMOTERS. THIS STIMULATION RESULTS IN THE ALTERED EXPRESSION OF RECEPTORS, SIGNALING MOLECULES, AND OTHER PROTEINS NECESSARY TO ALTER GENETIC REGULATORY CIRCUITS. WITH MORE CHRONIC EXPOSURE, CELLS ADAPT BY AN UNKNOWN HYPOTHETICAL PROCESS THAT RESULTS IN MORE PERMANENT MODIFICATIONS TO DNA METHYLATION AND CHROMATIN STRUCTURE, LEADING TO ENDURING ALTERATION OF A GIVEN EPIGENETIC NETWORK. THEREFORE, ANY EPIGENETIC SIDE-EFFECT CAUSED BY A DRUG MAY PERSIST AFTER THE DRUG IS DISCONTINUED. IT IS FURTHER PROPOSED THAT SOME IATROGENIC DISEASES SUCH AS TARDIVE DYSKINESIA AND DRUG-INDUCED SLE ARE EPIGENETIC IN NATURE. IF THIS HYPOTHESIS IS CORRECT THE CONSEQUENCES FOR MODERN MEDICINE ARE PROFOUND, SINCE IT WOULD IMPLY THAT OUR CURRENT UNDERSTANDING OF PHARMACOLOGY IS AN OVERSIMPLIFICATION. WE PROPOSE THAT EPIGENETIC SIDE-EFFECTS OF PHARMACEUTICALS MAY BE INVOLVED IN THE ETIOLOGY OF HEART DISEASE, CANCER, NEUROLOGICAL AND COGNITIVE DISORDERS, OBESITY, DIABETES, INFERTILITY, AND SEXUAL DYSFUNCTION. IT IS SUGGESTED THAT A SYSTEMS BIOLOGY APPROACH EMPLOYING MICROARRAY ANALYSES OF GENE EXPRESSION AND METHYLATION PATTERNS CAN LEAD TO A BETTER UNDERSTANDING OF LONG-TERM SIDE-EFFECTS OF DRUGS, AND THAT IN THE FUTURE, EPIGENETIC ASSAYS SHOULD BE INCORPORATED INTO THE SAFETY ASSESSMENT OF ALL PHARMACEUTICAL DRUGS. THIS NEW APPROACH TO PHARMACOLOGY HAS BEEN TERMED "PHAMACOEPIGENOMICS", THE IMPACT OF WHICH MAY BE EQUAL TO OR GREATER THAN THAT OF PHARMACOGENETICS. WE PROVIDE HERE AN OVERVIEW OF THIS POTENTIALLY MAJOR NEW FIELD IN PHARMACOLOGY AND MEDICINE. 2009 8 2338 25 EPIGENETIC REGULATION OF INFLAMMATORY SIGNALING AND INFLAMMATION-INDUCED CANCER. EPIGENETICS COMPRISE A DIVERSE ARRAY OF REVERSIBLE AND DYNAMIC MODIFICATIONS TO THE CELL'S GENOME WITHOUT IMPLICATING ANY DNA SEQUENCE ALTERATIONS. BOTH THE EXTERNAL ENVIRONMENT SURROUNDING THE ORGANISM, AS WELL AS THE INTERNAL MICROENVIRONMENT OF CELLS AND TISSUES, CONTRIBUTE TO THESE EPIGENETIC PROCESSES THAT PLAY CRITICAL ROLES IN CELL FATE SPECIFICATION AND ORGANISMAL DEVELOPMENT. ON THE OTHER HAND, DYSREGULATION OF EPIGENETIC ACTIVITIES CAN INITIATE AND SUSTAIN CARCINOGENESIS, WHICH IS OFTEN AUGMENTED BY INFLAMMATION. CHRONIC INFLAMMATION, ONE OF THE MAJOR HALLMARKS OF CANCER, STEMS FROM PROINFLAMMATORY CYTOKINES THAT ARE SECRETED BY TUMOR AND TUMOR-ASSOCIATED CELLS IN THE TUMOR MICROENVIRONMENT. AT THE SAME TIME, INFLAMMATORY SIGNALING CAN ESTABLISH POSITIVE AND NEGATIVE FEEDBACK CIRCUITS WITH CHROMATIN TO MODULATE CHANGES IN THE GLOBAL EPIGENETIC LANDSCAPE. IN THIS REVIEW, WE PROVIDE AN IN-DEPTH DISCUSSION OF THE INTERCONNECTED CROSSTALK BETWEEN EPIGENETICS AND INFLAMMATION, SPECIFICALLY HOW EPIGENETIC MECHANISMS AT DIFFERENT HIERARCHICAL LEVELS OF THE GENOME CONTROL INFLAMMATORY GENE TRANSCRIPTION, WHICH IN TURN ENACT CHANGES WITHIN THE CELL'S EPIGENOMIC PROFILE, ESPECIALLY IN THE CONTEXT OF INFLAMMATION-INDUCED CANCER. 2022 9 5581 21 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 10 5130 23 POSTTRANSCRIPTIONAL GENE REGULATION: NOVEL PATHWAYS FOR GLUCOCORTICOIDS' ANTI-INFLAMMATORY ACTION. POSTTRANSCRIPTIONAL GENE REGULATION (PTR) IS A FUNDAMENTAL BIOLOGICAL PROCESS THAT INTEGRATES WITH THE MASTER TRANSCRIPTIONAL CONTROL OF GENE EXPRESSION, IN WAYS THAT ONLY IN THE LAST DECADE HAVE BEEN INCREASINGLY UNDERSTOOD [1, 2]. WHILE EPIGENETIC AND TRANSCRIPTIONAL EVENTS SHAPE CELL RESPONSE QUALITATIVELY, DECIDING THE PATTERN OF GENE EXPRESSION TO 'SWITCH ON OR OFF' IN RESPONSE TO ENDOGENOUS OR ENVIRONMENTAL TRIGGERS, THE KEY TASK OF PTR IS TO ACT AS A 'RHEOSTAT' AND RAPIDLY ADAPT THE CELLULAR RESPONSE BY PROVIDING THE APPROPRIATE AMPLITUDE AND TIMING TO THE PROTEIN EXPRESSION PATTERNS [3, 4]. THE PIVOTAL ROLE OF THIS MECHANISM COMES TO THE FOREFRONT IN INFLAMMATORY AND IMMUNE RESPONSE, WHERE THE CHANGES IN AMPLITUDE AND DURATION IN THE EXPRESSION OF DANGEROUS AND PROTECTIVE GENES ARE IN DELICATE BALANCE, AND ARE CRITICAL IN DETERMINING EITHER THE SUCCESSFUL RESOLUTION OF THE IMMUNE RESPONSE OR ITS CHRONIC OVEREXPRESSION [5]. THIS BRIEF REVIEW INTRODUCES MEMBERS OF THE MAIN CLASSES OF MOLECULES MEDIATING THE CYTOPLASMIC ARM OF GENE REGULATION, NAMELY RNA-BINDING PROTEINS AND MICRO-RNA (MIRNA), AND SUMMARIZES EXPERIMENTAL DATA THAT UNDERSCORE THE ROLE OF THESE MOLECULES IN THE PATHOPHYSIOLOGY OF CHRONIC INFLAMMATION, AS WELL AS THEIR PROMISING VALUE AS MECHANISMS CONVEYING THE ANTI-INFLAMMATORY EFFECT OF SYNTHETIC GLUCOCORTICOIDS. 2012 11 1326 20 DEPLETION OF NUCLEAR HISTONE H2A VARIANTS IS ASSOCIATED WITH CHRONIC DNA DAMAGE SIGNALING UPON DRUG-EVOKED SENESCENCE OF HUMAN SOMATIC CELLS. CELLULAR SENESCENCE IS ASSOCIATED WITH GLOBAL CHROMATIN CHANGES, ALTERED GENE EXPRESSION, AND ACTIVATION OF CHRONIC DNA DAMAGE SIGNALING. THESE EVENTS ULTIMATELY LEAD TO MORPHOLOGICAL AND PHYSIOLOGICAL TRANSFORMATIONS IN PRIMARY CELLS. IN THIS STUDY, WE SHOW THAT CHRONIC DNA DAMAGE SIGNALS CAUSED BY GENOTOXIC STRESS IMPACT THE EXPRESSION OF HISTONES H2A FAMILY MEMBERS AND LEAD TO THEIR DEPLETION IN THE NUCLEI OF SENESCENT HUMAN FIBROBLASTS. OUR DATA REINFORCE THE HYPOTHESIS THAT PROGRESSIVE CHROMATIN DESTABILIZATION MAY LEAD TO THE LOSS OF EPIGENETIC INFORMATION AND IMPAIRED CELLULAR FUNCTION ASSOCIATED WITH CHRONIC DNA DAMAGE UPON DRUG-EVOKED SENESCENCE. WE PROPOSE THAT CHANGES IN THE HISTONE BIOSYNTHESIS AND CHROMATIN ASSEMBLY MAY DIRECTLY CONTRIBUTE TO CELLULAR AGING. IN ADDITION, WE ALSO OUTLINE THE METHOD THAT ALLOWS FOR QUANTITATIVE AND UNBIASED MEASUREMENT OF THESE CHANGES. 2012 12 5550 32 ROLE OF EPIGENETICS IN INFLAMMATION-ASSOCIATED DISEASES. THERE IS CONSIDERABLE EVIDENCE SUGGESTING THAT EPIGENETIC MECHANISMS MAY MEDIATE DEVELOPMENT OF CHRONIC INFLAMMATION BY MODULATING THE EXPRESSION OF PRO-INFLAMMATORY CYTOKINE TNF-ALPHA, INTERLEUKINS, TUMOR SUPPRESSOR GENES, ONCOGENES AND AUTOCRINE AND PARACRINE ACTIVATION OF THE TRANSCRIPTION FACTOR NF-KAPPAB. THESE MOLECULES ARE CONSTITUTIVELY PRODUCED BY A VARIETY OF CELLS UNDER CHRONIC INFLAMMATORY CONDITIONS, WHICH IN TURN LEADS TO THE DEVELOPMENT OF MAJOR DISEASES SUCH AS AUTOIMMUNE DISORDERS, CHRONIC OBSTRUCTIVE PULMONARY DISEASES, NEURODEGENERATIVE DISEASES AND CANCER. DISTINCT OR GLOBAL CHANGES IN THE EPIGENETIC LANDSCAPE ARE HALLMARKS OF CHRONIC INFLAMMATION DRIVEN DISEASES. EPIGENETICS INCLUDE CHANGES TO DISTINCT MARKERS ON THE GENOME AND ASSOCIATED CELLULAR TRANSCRIPTIONAL MACHINERY THAT ARE COPIED DURING CELL DIVISION (MITOSIS AND MEIOSIS). THESE CHANGES APPEAR FOR A SHORT SPAN OF TIME AND THEY NECESSARILY DO NOT MAKE PERMANENT CHANGES TO THE PRIMARY DNA SEQUENCE ITSELF. HOWEVER, THE MOST FREQUENTLY OBSERVED EPIGENETIC CHANGES INCLUDE ABERRANT DNA METHYLATION, AND HISTONE ACETYLATION AND DEACETYLATION. IN THIS CHAPTER, WE FOCUS ON PRO-INFLAMMATORY MOLECULES THAT ARE REGULATED BY ENZYMES INVOLVED IN EPIGENETIC MODIFICATIONS SUCH AS ARGININE AND LYSINE METHYL TRANSFERASES, DNA METHYLTRANSFERASE, HISTONE ACETYLTRANSFERASES AND HISTONE DEACETYLASES AND THEIR ROLE IN INFLAMMATION DRIVEN DISEASES. AGENTS THAT MODULATE OR INHIBIT THESE EPIGENETIC MODIFICATIONS, SUCH AS HAT OR HDAC INHIBITORS HAVE SHOWN GREAT POTENTIAL IN INHIBITING THE PROGRESSION OF THESE DISEASES. GIVEN THE PLASTICITY OF THESE EPIGENETIC CHANGES AND THEIR READINESS TO RESPOND TO INTERVENTION BY SMALL MOLECULE INHIBITORS, THERE IS A TREMENDOUS POTENTIAL FOR THE DEVELOPMENT OF NOVEL THERAPEUTICS THAT WILL SERVE AS DIRECT OR ADJUVANT THERAPEUTIC COMPOUNDS IN THE TREATMENT OF THESE DISEASES. 2013 13 4204 23 METABOLISM, EPIGENETICS, AND CAUSAL INFERENCE IN HEART FAILURE. EUKARYOTES MUST BALANCE THE METABOLIC AND CELL DEATH ACTIONS OF MITOCHONDRIA VIA CONTROL OF GENE EXPRESSION AND CELL FATE BY CHROMATIN, THEREBY FUNCTIONALLY BINDING THE METABOLOME AND EPIGENOME. THIS INTERACTION HAS FAR-REACHING IMPLICATIONS FOR CHRONIC DISEASES IN HUMANS, THE MOST COMMON OF WHICH ARE THOSE OF THE CARDIOVASCULAR SYSTEM. THE MOST DEVASTATING CONSEQUENCE OF CARDIOVASCULAR DISEASE, HEART FAILURE, IS NOT A SINGLE DISEASE, DIAGNOSIS, OR ENDPOINT. HUMAN AND ANIMAL STUDIES HAVE REVEALED THAT, REGARDLESS OF ETIOLOGY AND SYMPTOMS, HEART FAILURE IS UNIVERSALLY ASSOCIATED WITH ABNORMAL METABOLISM AND GENE EXPRESSION - TO FRAME THIS AS CAUSE OR CONSEQUENCE, HOWEVER, MAY BE TO WRONGFOOT THE QUESTION. THIS ESSAY AIMS TO CHALLENGE CURRENT THINKING ON METABOLIC-EPIGENETIC CROSSTALK IN HEART FAILURE, PRESENTING HYPOTHESES FOR HOW CHRONIC DISEASES ARISE, TAKE HOLD, AND PERSIST. WE UNPACK ASSUMPTIONS ABOUT THE ORDER OF OPERATIONS FOR GENE EXPRESSION AND METABOLISM, EXPLORING RECENT FINDINGS IN NONCARDIAC SYSTEMS THAT LINK METABOLIC INTERMEDIATES DIRECTLY TO CHROMATIN REMODELING. LASTLY, WE DISCUSS POTENTIAL MECHANISMS BY WHICH CHROMATIN MAY SERVE AS A SUBSTRATE FOR METABOLIC MEMORY, AND HOW CHANGES IN CELLULAR TRANSCRIPTOMES (AND HENCE IN CELLULAR BEHAVIOR) IN RESPONSE TO STRESS CORRESPOND TO GLOBAL CHANGES IN CHROMATIN ACCESSIBILITY AND STRUCTURE. 2020 14 2333 25 EPIGENETIC REGULATION OF INFLAMMATION: THE METABOLOMICS CONNECTION. EPIGENETIC FACTORS ARE CONSIDERED THE REGULATOR OF COMPLEX MACHINERY BEHIND INFLAMMATORY DISORDERS AND SIGNIFICANTLY CONTRIBUTED TO THE EXPRESSION OF INFLAMMATION-ASSOCIATED GENES. EPIGENETIC MODIFICATIONS MODULATE VARIATION IN THE EXPRESSION PATTERN OF TARGET GENES WITHOUT AFFECTING THE DNA SEQUENCE. THE CURRENT KNOWLEDGE OF EPIGENETIC RESEARCH FOCUSED ON THEIR ROLE IN THE PATHOGENESIS OF VARIOUS INFLAMMATORY DISEASES THAT CAUSES MORBIDITY AND MORTALITY WORLDWIDE. INFLAMMATORY DISEASES ARE CATEGORIZED AS ACUTE AND CHRONIC BASED ON THE DISEASE SEVERITY AND ARE REGULATED BY THE EXPRESSION PATTERN OF VARIOUS GENES. HENCE, UNDERSTANDING THE ROLE OF EPIGENETIC MODIFICATIONS DURING INFLAMMATION PROGRESSION WILL CONTRIBUTE TO THE DISEASE OUTCOMES AND THERAPEUTIC APPROACHES. THIS REVIEW ALSO FOCUSES ON THE METABOLOMICS APPROACH ASSOCIATED WITH THE STUDY OF INFLAMMATORY DISORDERS. INFLAMMATORY RESPONSES AND METABOLIC REGULATION ARE HIGHLY INTEGRATED AND VARIOUS ADVANCED TECHNIQUES ARE ADOPTED TO STUDY THE METABOLIC SIGNATURE MOLECULES. HERE WE DISCUSS SEVERAL METABOLOMICS APPROACHES USED TO LINK INFLAMMATORY DISORDERS AND EPIGENETIC CHANGES. WE PROPOSED THAT DECIPHERING THE MECHANISM BEHIND THE INFLAMMATION-METABOLISM LOOP MAY HAVE IMMENSE IMPORTANCE IN BIOMARKERS RESEARCH AND MAY ACT AS A PRINCIPAL COMPONENT IN DRUG DISCOVERY AS WELL AS THERAPEUTIC APPLICATIONS. 2022 15 6886 20 [ROLE OF EPIGENETIC MODIFICATION IN HIGHER BRAIN DYSFUNCTION AND AGING]. EPIGENETIC MECHANISMS TYPICALLY INVOLVE HERITABLE ALTERATIONS IN CHROMATIN STRUCTURE, WHICH, IN TURN, REGULATE GENE EXPRESSION. FUNDAMENTAL INSIGHTS ABOUT EPIGENETIC HERITABILITY HAVE COME FROM STUDIES OF CELL DIVISION AND DEVELOPMENT. HOWEVER, THERE IS INCREASING EVIDENCE THAT THE REGULATION OF CHROMATIN STRUCTURE THROUGH HISTONE MODIFICATIONS AND DNA METHYLATION MIGHT MEDIATE THE EXPRESSION OF KEY GENES INVOLVED IN ACQUIRED CHRONIC DISORDERS. THIS IDEA IS FASCINATING BECAUSE SIMILAR MECHANISMS ARE USED FOR TRIGGERING AND STORING LONG-TERM MEMORIES AT THE CELLULAR LEVEL DURING, FOR EXAMPLE, HIGHER-BRAIN DYSFUNCTION, STRESS DISEASE, DRUG DEPENDENCE, AGING, AND CHRONIC PAIN. THIS REVIEW WILL EXPLORE THE MOST CURRENT ISSUES IN THE FIELD OF EPIGENETICS, WITH A FOCUS ON NEXT LEVELS OF TRANSCRIPTIONAL MECHANISMS UNDERLYING AGING, ENRICHED ENVIRONMENT AND DRUG ADDICTION. EPIGENETIC MECHANISMS, WHICH ARE KEY CELLULAR AND MOLECULAR PROCESSES THAT INTEGRATE DIVERSE ENVIRONMENTAL STIMULI TO EXERT POTENT AND OFTEN LONG-LASTING CHANGES IN GENE EXPRESSION THROUGH THE REGULATION OF CHROMATIN STRUCTURE, CONTRIBUTE TO TRANSCRIPTIONAL AND BEHAVIORAL CHANGES. 2012 16 2592 21 EPIGENETICS OF RENAL DEVELOPMENT AND DISEASE. AN UNDERSTANDING OF EPIGENETICS IS INDISPENSABLE TO OUR UNDERSTANDING OF GENE REGULATION UNDER NORMAL AND PATHOLOGICAL STATES. THIS KNOWLEDGE WILL HELP WITH DESIGNING BETTER THERAPEUTIC APPROACHES IN REGENERATIVE TISSUE MEDICINE. EPIGENETICS ALLOWS US TO PARSE OUT THE MECHANISMS BY WHICH TRANSCRIPTIONAL REGULATORS GAIN ACCESS TO SPECIFIC GENE LOCI THEREBY IMPRINTING EPIGENETIC INFORMATION AFFECTING CHROMATIN FUNCTION. THIS EPIGENETIC MEMORY FORMS THE BASIS OF CELL LINEAGE SPECIFICATION IN MULTICELLULAR ORGANISMS. POST-TRANSLATIONAL MODIFICATIONS TO DNA AND HISTONES IN THE NUCLEOSOME CORE FORM CHARACTERISTIC EPIGENETIC CODES WHICH ARE DISTINCT FOR SELF-RENEWING AND PRIMED PROGENITOR CELL POPULATIONS. STUDIES OF CHROMATIN MODIFIERS AND MODIFICATIONS IN RENAL DEVELOPMENT AND DISEASE HAVE BEEN GAINING MOMENTUM. BOTH CONGENITAL AND ADULT RENAL DISEASES HAVE A GENE-ENVIRONMENT COMPONENT, WHICH INVOLVES ALTERATIONS TO THE EPIGENETIC INFORMATION IMPRINTED DURING DEVELOPMENT. THIS EPIGENETIC MEMORY MUST BE CHARACTERIZED TO ESTABLISH OPTIMAL TREATMENT OF BOTH ACUTE AND CHRONIC RENAL DISEASES. 2016 17 4738 26 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 18 733 26 CANCER EPIGENETICS: LINKING BASIC BIOLOGY TO CLINICAL MEDICINE. CANCER EVOLUTION AT ALL STAGES IS DRIVEN BY BOTH EPIGENETIC ABNORMALITIES AS WELL AS GENETIC ALTERATIONS. DYSREGULATION OF EPIGENETIC CONTROL EVENTS MAY LEAD TO ABNORMAL PATTERNS OF DNA METHYLATION AND CHROMATIN CONFIGURATIONS, BOTH OF WHICH ARE CRITICAL CONTRIBUTORS TO THE PATHOGENESIS OF CANCER. THESE EPIGENETIC ABNORMALITIES ARE SET AND MAINTAINED BY MULTIPLE PROTEIN COMPLEXES AND THE INTERPLAY BETWEEN THEIR INDIVIDUAL COMPONENTS INCLUDING DNA METHYLATION MACHINERY, HISTONE MODIFIERS, PARTICULARLY, POLYCOMB (PCG) PROTEINS, AND CHROMATIN REMODELING PROTEINS. RECENT ADVANCES IN GENOME-WIDE TECHNOLOGY HAVE REVEALED THAT THE INVOLVEMENT OF THESE DYSREGULATED EPIGENETIC COMPONENTS APPEARS TO BE EXTENSIVE. MOREOVER, THERE IS A GROWING CONNECTION BETWEEN EPIGENETIC ABNORMALITIES IN CANCER AND CONCEPTS CONCERNING STEM-LIKE CELL SUBPOPULATIONS AS A DRIVING FORCE FOR CANCER. EMERGING DATA SUGGEST THAT ASPECTS OF THE EPIGENETIC LANDSCAPE INHERENT TO NORMAL EMBRYONIC AND ADULT STEM/PROGENITOR CELLS MAY HELP FOSTER, UNDER THE STRESS OF CHRONIC INFLAMMATION OR ACCUMULATING REACTIVE OXYGEN SPECIES, EVOLUTION OF MALIGNANT SUBPOPULATIONS. FINALLY, UNDERSTANDING MOLECULAR MECHANISMS INVOLVED IN INITIATION AND MAINTENANCE OF EPIGENETIC ABNORMALITIES IN ALL TYPES OF CANCER HAS GREAT POTENTIAL FOR TRANSLATIONAL PURPOSES. THIS IS ALREADY EVIDENT FOR EPIGENETIC BIOMARKER DEVELOPMENT, AND FOR PHARMACOLOGICAL TARGETING AIMED AT REVERSING CANCER-SPECIFIC EPIGENETIC ALTERATIONS. 2011 19 2541 26 EPIGENETICS IN KIDNEY DEVELOPMENT AND RENAL DISEASE. THE STUDY OF EPIGENETICS IS INTIMATELY LINKED AND INSEPARABLE FROM DEVELOPMENTAL BIOLOGY. MANY OF THE GENES THAT IMPRINT EPIGENETIC INFORMATION ON CHROMATIN FUNCTION DURING THE SPECIFICATION OF CELL LINEAGES IN THE DEVELOPING EMBRYO. THESE INCLUDE THE HISTONE METHYLTRANSFERASES AND THEIR COFACTORS OF THE POLYCOMB AND TRITHORAX GENE FAMILIES. HOW HISTONE METHYLATION IS ESTABLISHED AND WHAT REGULATES THE TISSUE AND LOCUS SPECIFICITY OF HISTONE METHYLATION IS AN EMERGING AREA OF RESEARCH. THE EMBRYONIC KIDNEY IS USED AS A MODEL TO UNDERSTAND HOW DNA-BINDING PROTEINS CAN SPECIFY CELL LINEAGES AND HOW SUCH PROTEINS INTERACT DIRECTLY WITH THE HISTONE METHYLATION MACHINERY TO GENERATE A UNIQUE EPIGENOME FOR PARTICULAR TISSUES AND CELL TYPES. IN ADULT TISSUES, HISTONE METHYLATION MARKS MUST BE MAINTAINED FOR NORMAL GENE EXPRESSION PATTERNS. IN CHRONIC AND ACUTE RENAL DISEASE, EPIGENETIC MARKS ARE BEING CHARACTERIZED AND CORRELATED WITH THE ESTABLISHMENT OF METABOLIC MEMORY, IN PART TO EXPLAIN THE PERSISTENCE OF PATHOLOGIES EVEN WHEN OPTIMAL TREATMENT MODALITIES ARE USED. THUS, THE STATE OF THE EPIGENOME IN ADULT CELLS MUST BE CONSIDERED WHEN ATTEMPTING TO ALLEVIATE OR ALTER GENE EXPRESSION PATTERNS IN DISEASE. 2015 20 5410 23 REGULATION OF ADAPTIVE IMMUNE CELLS BY SIRTUINS. IT IS NOW WELL-ESTABLISHED THAT THE PATHWAYS THAT CONTROL LYMPHOCYTE METABOLISM AND FUNCTION ARE INTIMATELY LINKED, AND CHANGES IN LYMPHOCYTE METABOLISM CAN INFLUENCE AND DIRECT CELLULAR FUNCTION. INTERESTINGLY, A NUMBER OF RECENT ADVANCES INDICATE THAT LYMPHOCYTE IDENTITY AND METABOLISM IS PARTIALLY CONTROLLED VIA EPIGENETIC REGULATION. EPIGENETIC MECHANISMS, SUCH AS CHANGES IN DNA METHYLATION OR HISTONE ACETYLATION, HAVE BEEN FOUND TO ALTER IMMUNE FUNCTION AND PLAY A ROLE IN NUMEROUS CHRONIC DISEASE STATES. THERE ARE SEVERAL ENZYMES THAT CAN MEDIATE EPIGENETIC CHANGES; OF PARTICULAR INTEREST ARE SIRTUINS, PROTEIN DEACETYLASES THAT MEDIATE ADAPTIVE RESPONSES TO A VARIETY OF STRESSES (INCLUDING CALORIE RESTRICTION AND METABOLIC STRESS) AND ARE NOW UNDERSTOOD TO PLAY A SIGNIFICANT ROLE IN IMMUNITY. THIS REVIEW WILL FOCUS ON RECENT ADVANCES IN THE UNDERSTANDING OF HOW SIRTUINS AFFECT THE ADAPTIVE IMMUNE SYSTEM. THESE PATHWAYS ARE OF SIGNIFICANT INTEREST AS THERAPEUTIC TARGETS FOR THE TREATMENT OF AUTOIMMUNITY, CANCER, AND TRANSPLANT TOLERANCE. 2019