1 2023 79 EPIGENETIC CHANGES BY DNA METHYLATION IN CHRONIC AND INTERMITTENT HYPOXIA. DNA METHYLATION OF CYTOSINE RESIDUES IS A WELL-STUDIED EPIGENETIC CHANGE, WHICH REGULATES GENE TRANSCRIPTION BY ALTERING ACCESSIBILITY FOR TRANSCRIPTION FACTORS. HYPOXIA IS A PERVASIVE STIMULUS THAT AFFECTS MANY PHYSIOLOGICAL PROCESSES. THE CIRCULATORY AND RESPIRATORY SYSTEMS ADAPT TO CHRONIC SUSTAINED HYPOXIA, SUCH AS THAT ENCOUNTERED DURING A HIGH-ALTITUDE SOJOURN. MANY PEOPLE LIVING AT SEA LEVEL EXPERIENCE CHRONIC INTERMITTENT HYPOXIA (IH) DUE TO SLEEP APNEA, WHICH LEADS TO CARDIOVASCULAR AND RESPIRATORY MALADAPTATION. THIS ARTICLE PRESENTS A BRIEF UPDATE ON EMERGING EVIDENCE SUGGESTING THAT CHANGES IN DNA METHYLATION CONTRIBUTE TO PATHOLOGIES CAUSED BY CHRONIC IH AND POTENTIALLY MEDIATE ADAPTATIONS TO CHRONIC SUSTAINED HYPOXIA BY AFFECTING THE HYPOXIA-INDUCIBLE FACTOR (HIF) SIGNALING PATHWAY. 2017 2 2567 25 EPIGENETICS MODIFIERS: POTENTIAL HUB FOR UNDERSTANDING AND TREATING NEURODEVELOPMENTAL DISORDERS FROM HYPOXIC INJURY. BACKGROUND: THE FETAL BRAIN IS ADAPTED TO THE HYPOXIC CONDITIONS PRESENT DURING NORMAL IN UTERO DEVELOPMENT. RELATIVELY MORE HYPOXIC STATES, EITHER CHRONIC OR ACUTE, ARE PATHOLOGIC AND CAN LEAD TO SIGNIFICANT LONG-TERM NEURODEVELOPMENTAL SEQUELAE. IN UTERO HYPOXIC INJURY IS ASSOCIATED WITH NEONATAL MORTALITY AND MILLIONS OF LIVES LIVED WITH VARYING DEGREES OF DISABILITY. MAIN BODY: GENETIC STUDIES OF CHILDREN WITH NEURODEVELOPMENTAL DISEASE INDICATE THAT EPIGENETIC MODIFIERS REGULATING DNA METHYLATION AND HISTONE REMODELING ARE CRITICAL FOR NORMAL BRAIN DEVELOPMENT. EPIGENETIC MODIFIERS ARE ALSO REGULATED BY ENVIRONMENTAL STIMULI, SUCH AS HYPOXIA. INDEED, EPIGENETIC MODIFIERS THAT ARE MUTATED IN CHILDREN WITH GENETIC NEURODEVELOPMENTAL DISEASES ARE REGULATED BY HYPOXIA IN A NUMBER OF PRECLINICAL MODELS AND MAY BE PART OF THE MECHANISM FOR THE LONG-TERM NEURODEVELOPMENTAL SEQUELAE SEEM IN CHILDREN WITH HYPOXIC BRAIN INJURY. THUS, A COMPREHENSIVE UNDERSTANDING THE ROLE OF DNA METHYLATION AND HISTONE MODIFICATIONS IN HYPOXIC INJURY IS CRITICAL FOR DEVELOPING NOVEL STRATEGIES TO TREAT CHILDREN WITH HYPOXIC INJURY. CONCLUSIONS: THIS REVIEW FOCUSES ON OUR CURRENT UNDERSTANDING OF THE INTERSECTION BETWEEN EPIGENETICS, BRAIN DEVELOPMENT, AND HYPOXIA. OPPORTUNITIES FOR THE USE OF EPIGENETICS AS BIOMARKERS OF NEURODEVELOPMENTAL DISEASE AFTER HYPOXIC INJURY AND POTENTIAL CLINICAL EPIGENETICS TARGETS TO IMPROVE OUTCOMES AFTER INJURY ARE ALSO DISCUSSED. WHILE THERE HAVE BEEN MANY PUBLISHED STUDIES ON THE EPIGENETICS OF HYPOXIA, MORE ARE NEEDED IN THE DEVELOPING BRAIN IN ORDER TO DETERMINE WHICH EPIGENETIC PATHWAYS MAY BE MOST IMPORTANT FOR MITIGATING THE LONG-TERM CONSEQUENCES OF HYPOXIC BRAIN INJURY. 2020 3 2499 19 EPIGENETICS AND EXERCISE. EPIGENETICS CAN BE DEFINED AS 'THE STRUCTURAL ADAPTATION OF CHROMOSOMAL REGIONS SO AS TO REGISTER, SIGNAL, OR PERPETUATE ALTERED ACTIVITY STATES.' INCREASED TRANSCRIPTION OF KEY REGULATORY, METABOLIC, AND MYOGENIC GENES IS AN EARLY RESPONSE TO EXERCISE AND IS IMPORTANT IN MEDIATING SUBSEQUENT ADAPTATIONS IN SKELETAL MUSCLE. DNA HYPOMETHYLATION AND HISTONE HYPERACETYLATION ARE EMERGING AS IMPORTANT CRUCIAL EVENTS FOR INCREASED TRANSCRIPTION. THE COMPLEX INTERACTIONS BETWEEN MULTIPLE EPIGENETIC MODIFICATIONS AND THEIR REGULATION BY METABOLIC CHANGES AND SIGNALING EVENTS DURING EXERCISE, WITH IMPLICATIONS FOR ENHANCED UNDERSTANDING OF THE ACUTE AND CHRONIC ADAPTATIONS TO EXERCISE, ARE QUESTIONS FOR FURTHER INVESTIGATION. 2019 4 2614 26 EPIGENETICS: NEW QUESTIONS ON THE RESPONSE TO HYPOXIA. REDUCTION IN OXYGEN LEVELS BELOW NORMAL CONCENTRATIONS PLAYS IMPORTANT ROLES IN DIFFERENT NORMAL AND PATHOLOGICAL CONDITIONS, SUCH AS DEVELOPMENT, TUMORIGENESIS, CHRONIC KIDNEY DISEASE AND STROKE. ORGANISMS EXPOSED TO HYPOXIA TRIGGER CHANGES AT BOTH CELLULAR AND SYSTEMIC LEVELS TO RECOVER OXYGEN HOMEOSTASIS. MOST OF THESE PROCESSES ARE MEDIATED BY HYPOXIA INDUCIBLE FACTORS, HIFS, A FAMILY OF TRANSCRIPTION FACTORS THAT DIRECTLY INDUCE THE EXPRESSION OF SEVERAL HUNDRED GENES IN MAMMALIAN CELLS. ALTHOUGH DIFFERENT ASPECTS OF HIF REGULATION ARE WELL KNOWN, IT IS STILL UNCLEAR BY WHICH PRECISE MECHANISM HIFS ACTIVATE TRANSCRIPTION OF THEIR TARGET GENES. CONCOMITANTLY, HYPOXIA PROVOKES A DRAMATIC DECREASE OF GENERAL TRANSCRIPTION THAT SEEMS TO RELY IN PART ON EPIGENETIC CHANGES THROUGH A POORLY UNDERSTOOD MECHANISM. IN THIS REVIEW WE DISCUSS THE CURRENT KNOWLEDGE ON CHROMATIN CHANGES INVOLVED IN HIF DEPENDENT GENE ACTIVATION, AS WELL AS ON OTHER EPIGENETIC CHANGES, NOT NECESSARILY LINKED TO HIF THAT TAKE PLACE UNDER HYPOXIC CONDITIONS. 2011 5 3581 27 IMPACT OF PHYSICAL ACTIVITY AND EXERCISE ON THE EPIGENOME IN SKELETAL MUSCLE AND EFFECTS ON SYSTEMIC METABOLISM. EXERCISE AND PHYSICAL ACTIVITY INDUCES PHYSIOLOGICAL RESPONSES IN ORGANISMS, AND ADAPTATIONS IN SKELETAL MUSCLE, WHICH IS BENEFICIAL FOR MAINTAINING HEALTH AND PREVENTING AND/OR TREATING MOST CHRONIC DISEASES. THESE ADAPTATIONS ARE MAINLY INSTIGATED BY TRANSCRIPTIONAL RESPONSES THAT ENSUE IN REACTION TO EACH INDIVIDUAL EXERCISE, EITHER RESISTANCE OR ENDURANCE. CONSEQUENTLY, CHANGES IN KEY METABOLIC, REGULATORY, AND MYOGENIC GENES IN SKELETAL MUSCLE OCCUR AS BOTH AN EARLY AND LATE RESPONSE TO EXERCISE, AND THESE EPIGENETIC MODIFICATIONS, WHICH ARE INFLUENCED BY ENVIRONMENTAL AND GENETIC FACTORS, TRIGGER THOSE ALTERATIONS IN THE TRANSCRIPTIONAL RESPONSES. DNA METHYLATION AND HISTONE MODIFICATIONS ARE THE MOST SIGNIFICANT EPIGENETIC CHANGES DESCRIBED IN GENE TRANSCRIPTION, LINKED TO THE SKELETAL MUSCLE TRANSCRIPTIONAL RESPONSE TO EXERCISE, AND MEDIATING THE EXERCISE ADAPTATIONS. NEVERTHELESS, OTHER ALTERATIONS IN THE EPIGENETICS MARKERS, SUCH AS EPITRANSCRIPTOMICS, MODIFICATIONS MEDIATED BY MIRNAS, AND LACTYLATION AS A NOVEL EPIGENETIC MODIFICATION, ARE EMERGING AS KEY EVENTS FOR GENE TRANSCRIPTION. HERE, WE PROVIDE AN OVERVIEW AND UPDATE OF THE IMPACT OF EXERCISE ON EPIGENETIC MODIFICATIONS, INCLUDING THE WELL-DESCRIBED DNA METHYLATIONS AND HISTONE MODIFICATIONS, AND THE EMERGING MODIFICATIONS IN THE SKELETAL MUSCLE. IN ADDITION, WE DESCRIBE THE EFFECTS OF EXERCISE ON EPIGENETIC MARKERS IN OTHER METABOLIC TISSUES; ALSO, WE PROVIDE INFORMATION ABOUT HOW SYSTEMIC METABOLISM OR ITS METABOLITES INFLUENCE EPIGENETIC MODIFICATIONS IN THE SKELETAL MUSCLE. 2022 6 6886 27 [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 7 2346 25 EPIGENETIC REGULATION OF METABOLISM AND INFLAMMATION BY CALORIE RESTRICTION. CHRONIC CALORIC RESTRICTION (CR) WITHOUT MALNUTRITION IS KNOWN TO AFFECT DIFFERENT CELLULAR PROCESSES SUCH AS STEM CELL FUNCTION, CELL SENESCENCE, INFLAMMATION, AND METABOLISM. DESPITE THE DIFFERENCES IN THE IMPLEMENTATION OF CR, THE REDUCTION OF CALORIES PRODUCES A WIDESPREAD BENEFICIAL EFFECT IN NONCOMMUNICABLE CHRONIC DISEASES, WHICH CAN BE EXPLAINED BY IMPROVEMENTS IN IMMUNO-METABOLIC ADAPTATION. CELLULAR ADAPTATION THAT OCCURS IN RESPONSE TO DIETARY PATTERNS CAN BE EXPLAINED BY ALTERATIONS IN EPIGENETIC MECHANISMS SUCH AS DNA METHYLATION, HISTONE MODIFICATIONS, AND MICRORNA. IN THIS REVIEW, WE DEFINE THESE MODIFICATIONS AND SYSTEMATICALLY SUMMARIZE THE CURRENT EVIDENCE RELATED TO CR AND THE EPIGENOME. WE THEN EXPLAIN THE SIGNIFICANCE OF GENOME-WIDE EPIGENETIC MODIFICATIONS IN THE CONTEXT OF DISEASE DEVELOPMENT. ALTHOUGH SUBSTANTIAL EVIDENCE EXISTS FOR THE WIDESPREAD EFFECT OF CR ON LONGEVITY, THERE IS NO CONSENSUS REGARDING THE EPIGENETIC REGULATIONS OF THE UNDERLYING CELLULAR MECHANISMS THAT LEAD TO IMPROVED HEALTH. WE PROVIDE COMPELLING EVIDENCE THAT CR PRODUCES LONG-LASTING EPIGENETIC EFFECTS THAT MEDIATE EXPRESSION OF GENES RELATED TO IMMUNO-METABOLIC PROCESSES. EPIGENETIC REPROGRAMMING OF THE UNDERLYING CHRONIC LOW-GRADE INFLAMMATION BY CR CAN LEAD TO IMMUNO-METABOLIC ADAPTATIONS THAT ENHANCE QUALITY OF LIFE, EXTEND LIFESPAN, AND DELAY CHRONIC DISEASE ONSET. 2019 8 860 24 CHROMATIN MODIFICATIONS DURING REPAIR OF ENVIRONMENTAL EXPOSURE-INDUCED DNA DAMAGE: A POTENTIAL MECHANISM FOR STABLE EPIGENETIC ALTERATIONS. EXPOSURES TO ENVIRONMENTAL TOXICANTS AND TOXINS CAUSE EPIGENETIC CHANGES THAT LIKELY PLAY A ROLE IN THE DEVELOPMENT OF DISEASES ASSOCIATED WITH EXPOSURE. THE MECHANISM BEHIND THESE EXPOSURE-INDUCED EPIGENETIC CHANGES IS CURRENTLY UNKNOWN. ONE COMMONALITY BETWEEN MOST ENVIRONMENTAL EXPOSURES IS THAT THEY CAUSE DNA DAMAGE EITHER DIRECTLY OR THROUGH CAUSING AN INCREASE IN REACTIVE OXYGEN SPECIES, WHICH CAN DAMAGE DNA. LIKE TRANSCRIPTION, DNA DAMAGE REPAIR MUST OCCUR IN THE CONTEXT OF CHROMATIN REQUIRING BOTH HISTONE MODIFICATIONS AND ATP-DEPENDENT CHROMATIN REMODELING. THESE CHROMATIN CHANGES AID IN DNA DAMAGE ACCESSIBILITY AND SIGNALING. SEVERAL PROTEINS AND COMPLEXES INVOLVED IN EPIGENETIC SILENCING DURING BOTH DEVELOPMENT AND CANCER HAVE BEEN FOUND TO BE LOCALIZED TO SITES OF DNA DAMAGE. THE CHROMATIN-BASED RESPONSE TO DNA DAMAGE IS CONSIDERED A TRANSIENT EVENT, WITH CHROMATIN BEING RESTORED TO NORMAL AS DNA DAMAGE REPAIR IS COMPLETED. HOWEVER, IN INDIVIDUALS CHRONICALLY EXPOSED TO ENVIRONMENTAL TOXICANTS OR WITH CHRONIC INFLAMMATORY DISEASE, REPEATED DNA DAMAGE-INDUCED CHROMATIN REARRANGEMENT MAY ULTIMATELY LEAD TO PERMANENT EPIGENETIC ALTERATIONS. UNDERSTANDING THE MECHANISM BEHIND EXPOSURE-INDUCED EPIGENETIC CHANGES WILL ALLOW US TO DEVELOP STRATEGIES TO PREVENT OR REVERSE THESE CHANGES. THIS REVIEW FOCUSES ON EPIGENETIC CHANGES AND DNA DAMAGE INDUCED BY ENVIRONMENTAL EXPOSURES, THE CHROMATIN CHANGES THAT OCCUR AROUND SITES OF DNA DAMAGE, AND HOW THESE TRANSIENT CHROMATIN CHANGES MAY LEAD TO HERITABLE EPIGENETIC ALTERATIONS AT SITES OF CHRONIC EXPOSURE. 2014 9 4542 20 MURINE MODELS OF SLEEP APNEA: FUNCTIONAL IMPLICATIONS OF ALTERED MACROPHAGE POLARITY AND EPIGENETIC MODIFICATIONS IN ADIPOSE AND VASCULAR TISSUES. OBSTRUCTIVE SLEEP APNEA (OSA) IS A HIGHLY PREVALENT DISEASE ACROSS THE LIFESPAN, IS CHARACTERIZED BY CHRONIC INTERMITTENT HYPOXIA AND SLEEP FRAGMENTATION, AND HAS BEEN INDEPENDENTLY ASSOCIATED WITH SUBSTANTIAL CARDIOMETABOLIC MORBIDITY. HOWEVER, THE REVERSIBILITY OF END-ORGAN MORBIDITY WITH TREATMENT IS NOT ALWAYS APPARENT, SUGGESTING THAT BOTH TISSUE REMODELING AND EPIGENETIC MECHANISMS MAY BE OPERATIONALLY INVOLVED. HERE, WE REVIEW THE CUMULATIVE EVIDENCE FOCUSED AROUND MURINE MODELS OF OSA TO ILLUSTRATE THE TEMPORAL DEPENDENCIES OF CARDIOMETABOLIC DYSFUNCTION AND ITS REVERSIBILITY, AND MORE PARTICULARLY TO DISCUSS THE CRITICAL CONTRIBUTIONS OF TISSUE MACROPHAGES TO ADIPOSE TISSUE INSULIN RESISTANCE AND VASCULAR ATHEROGENESIS. IN ADDITION, WE DESCRIBE INITIAL FINDINGS POTENTIALLY IMPLICATING EPIGENETIC ALTERATIONS IN BOTH THE EMERGENCE OF THE CARDIOMETABOLIC MORBIDITY OF OSA, AND IN ITS REVERSIBILITY WITH TREATMENT. WE ANTICIPATE THAT IMPROVED UNDERSTANDING OF MACROPHAGE BIOLOGY AND EPIGENETICS IN THE CONTEXT OF INTERMITTENT HYPOXIA AND SLEEP FRAGMENTATION WILL LEAD TO DISCOVERY OF NOVEL THERAPEUTIC TARGETS AND IMPROVED CARDIOVASCULAR AND METABOLIC OUTCOMES IN OSA. 2018 10 2360 21 EPIGENETIC REGULATION OF SKELETAL MUSCLE METABOLISM. NORMAL SKELETAL MUSCLE METABOLISM IS ESSENTIAL FOR WHOLE BODY METABOLIC HOMOEOSTASIS AND DISRUPTIONS IN MUSCLE METABOLISM ARE ASSOCIATED WITH A NUMBER OF CHRONIC DISEASES. TRANSCRIPTIONAL CONTROL OF METABOLIC ENZYME EXPRESSION IS A MAJOR REGULATORY MECHANISM FOR MUSCLE METABOLIC PROCESSES. SUBSTANTIAL EVIDENCE IS EMERGING THAT HIGHLIGHTS THE IMPORTANCE OF EPIGENETIC MECHANISMS IN THIS PROCESS. THIS REVIEW WILL EXAMINE THE IMPORTANCE OF EPIGENETICS IN THE REGULATION OF MUSCLE METABOLISM, WITH A PARTICULAR EMPHASIS ON DNA METHYLATION AND HISTONE ACETYLATION AS EPIGENETIC CONTROL POINTS. THE EMERGING CROSS-TALK BETWEEN METABOLISM AND EPIGENETICS IN THE CONTEXT OF HEALTH AND DISEASE WILL ALSO BE EXAMINED. THE CONCEPT OF INHERITANCE OF SKELETAL MUSCLE METABOLIC PHENOTYPES WILL BE DISCUSSED, IN ADDITION TO EMERGING EPIGENETIC THERAPIES THAT COULD BE USED TO ALTER MUSCLE METABOLISM IN CHRONIC DISEASE STATES. 2016 11 6533 26 TRANSCRIPTIONAL REGULATION OF INFLAMMATORY GENES ASSOCIATED WITH SEVERE ASTHMA. THE 10% OF PATIENTS WITH THE MOST SEVERE ASTHMA ARE RESPONSIBLE FOR A LARGE PART OF HEALTHCARE EXPENDITURE AND MORBIDITY. UNDERSTANDING THE PROCESSES INVOLVED IS KEY IF NEW THERAPEUTIC APPROACHES ARE TO BE DEVELOPED. EVIDENCE IS ACCUMULATING THAT CHRONIC DISEASES SUCH AS ASTHMA ARE ASSOCIATED WITH TEMPORAL AND SPATIAL ALTERATIONS IN THE PATTERN OF INFLAMMATORY GENE EXPRESSION WITHIN THE AIRWAYS. EXPRESSION OF THESE GENES CAN BE REGULATED BY TRANSCRIPTIONAL, POSTTRANSCRIPTIONAL, TRANSLATIONAL AND EPIGENETIC MECHANISMS. IT IS WELL ESTABLISHED THAT BINDING OF ACTIVATED TRANSCRIPTION FACTORS TO SPECIFIC INDUCIBLE GENE PROMOTER SITES IS TIGHTLY CONTROLLED BY CHROMATIN STATE AS A RESULT OF HISTONE MODIFICATIONS, PARTICULARLY THE BALANCE BETWEEN HISTONE ACETYLATION AND DEACETYLATION [1]. THE INTERACTION BETWEEN TRANSCRIPTION FACTORS AND THE PROMOTER IS KEY TO THE DIVERSIFICATION OF GENE EXPRESSION IN A TIME DEPENDENT MANNER LEADING TO ALTERED GENE EXPRESSION PROFILES. ALTERATIONS OF THE ACCESSIBILITY OF TRANSCRIPTION FACTORS TO THE DNA CAN HAVE RESIDING EFFECTS UPON GENE TRANSCRIPTION. THIS REVIEW WILL FOCUS ON THE REGULATION OF SEVERAL GROUPS OF KEY GENES WHICH ARE INVOLVED IN CHRONIC AIRWAY INFLAMMATION AND REMODELLING IN ASTHMA DRAWING MAINLY FROM OUR EXPERIENCE OF STUDYING THESE PROCESSES IN AIRWAY SMOOTH MUSCLE CELLS. AN OVERVIEW IS SHOWN IN FIGURE 1. 2011 12 1982 26 EPIGENETIC ALTERATIONS IN PEDIATRIC SLEEP APNEA. PEDIATRIC OBSTRUCTIVE SLEEP APNEA HAS SIGNIFICANT NEGATIVE EFFECTS ON HEALTH AND BEHAVIOR IN CHILDHOOD INCLUDING DEPRESSION, FAILURE TO THRIVE, NEUROCOGNITIVE IMPAIRMENT, AND BEHAVIORAL ISSUES. IT IS STRONGLY ASSOCIATED WITH AN INCREASED RISK FOR CHRONIC ADULT DISEASE SUCH AS OBESITY AND DIABETES, ACCELERATED ATHEROSCLEROSIS, AND ENDOTHELIAL DYSFUNCTION. ACCUMULATING EVIDENCE SUGGESTS THAT ADULT-ONSET NON-COMMUNICABLE DISEASES MAY ORIGINATE FROM EARLY LIFE THROUGH A PROCESS BY WHICH AN INSULT APPLIED AT A CRITICAL DEVELOPMENTAL WINDOW CAUSES LONG-TERM EFFECTS ON THE STRUCTURE OR FUNCTION OF AN ORGANISM. IN RECENT YEARS, THERE HAS BEEN INCREASED INTEREST IN THE ROLE OF EPIGENETIC MECHANISMS IN THE PATHOGENESIS OF ADULT DISEASE SUSCEPTIBILITY. EPIGENETIC MECHANISMS THAT INFLUENCE ADAPTIVE VARIABILITY INCLUDE HISTONE MODIFICATIONS, NON-CODING RNAS, AND DNA METHYLATION. THIS REVIEW WILL HIGHLIGHT WHAT IS CURRENTLY KNOWN ABOUT THE PHENOTYPIC ASSOCIATIONS OF EPIGENETIC MODIFICATIONS IN PEDIATRIC OBSTRUCTIVE SLEEP APNEA AND WILL EMPHASIZE THE IMPORTANCE OF EPIGENETIC CHANGES AS BOTH MODULATORS OF CHRONIC DISEASE AND POTENTIAL THERAPEUTIC TARGETS. 2021 13 6543 18 TRANSCRIPTOME REMODELING IN HYPOXIC INFLAMMATION. HYPOXIA IS AN INTEGRAL COMPONENT OF THE INFLAMED TISSUE MICROENVIRONMENT. TODAY, THE INFLUENCE OF HYPOXIA ON THE NATURAL EVOLUTION OF INFLAMMATORY RESPONSES IS WIDELY ACCEPTED; HOWEVER, MANY MOLECULAR AND CELLULAR MECHANISMS MEDIATING THIS RELATIONSHIP REMAIN TO BE CLARIFIED. HYPOXIC STRESS AFFECTS SEVERAL INDEPENDENT TRANSCRIPTIONAL REGULATORS RELATED TO INFLAMMATION IN WHICH HIF-1 AND NF-KAPPAB PLAY CENTRAL ROLES. TRANSCRIPTION FACTORS INTERACT WITH BOTH HATS AND HDACS, WHICH ARE COMPONENTS OF LARGE MULTIPROTEIN CO-REGULATORY COMPLEXES. THIS REVIEW SUMMARIZES THE CURRENT KNOWLEDGE ON HYPOXIA-RESPONSIVE TRANSCRIPTIONAL PATHWAYS IN INFLAMMATION AND THEIR IMPORTANCE IN THE ETIOLOGY OF CHRONIC INFLAMMATORY DISEASES, WITH THE PRIMARY FOCUS ON TRANSCRIPTIONAL CO-REGULATORS AND HISTONE MODIFICATIONS IN DEFINING GENE-SPECIFIC TRANSCRIPTIONAL RESPONSES IN HYPOXIA, AND ON THE RECENT PROGRESS IN THE UNDERSTANDING OF HYPOXIA-MEDIATED EPIGENETIC REPROGRAMMING. FURTHERMORE, THIS REVIEW DISCUSSES THE MOLECULAR CROSS-TALK BETWEEN GLUCOCORTICOID ANTI-INFLAMMATORY PATHWAYS AND HYPOXIA. 2010 14 4126 26 MECHANISMS OF DISEASE: THE DEVELOPMENTAL ORIGINS OF DISEASE AND THE ROLE OF THE EPIGENOTYPE. THERE IS ACCUMULATING EVIDENCE THAT MANY CHRONIC DISEASES SUCH AS TYPE 2 DIABETES AND CORONARY HEART DISEASE MIGHT ORIGINATE DURING EARLY LIFE. THIS EVIDENCE GIVES RISE TO THE DEVELOPMENTAL ORIGINS OF DISEASE HYPOTHESIS, AND IS SUPPORTED BY EPIDEMIOLOGICAL DATA IN HUMANS AND EXPERIMENTAL ANIMAL MODELS. A PERTURBED ENVIRONMENT IN EARLY LIFE IS THOUGHT TO ELICIT A RANGE OF PHYSIOLOGICAL AND CELLULAR ADAPTIVE RESPONSES IN KEY ORGAN SYSTEMS. THESE ADAPTIVE CHANGES RESULT IN PERMANENT ALTERATIONS AND MIGHT LEAD TO PATHOLOGY IN LATER LIFE. AGING ORGANS AND CELLS SEEM THEREFORE TO RETAIN A 'MEMORY' OF THEIR FETAL HISTORY AND ADAPTIVE RESPONSES. THE MECHANISMS UNDERLYING THE DEVELOPMENTAL ORIGINS OF DISEASE REMAIN POORLY DEFINED. EPIGENETIC TAGGING OF GENES, SUCH AS DNA METHYLATION AND HISTONE MODIFICATION, CONTROLS THE FUNCTION OF THE GENOME AT DIFFERENT LEVELS AND MAINTAINS CELLULAR MEMORY AFTER MANY CELLULAR DIVISIONS; IMPORTANTLY, TAGGING CAN BE MODULATED BY THE ENVIRONMENT AND IS INVOLVED IN ONSET OF DISEASES SUCH AS CANCER. HERE WE REVIEW THE EVIDENCE FOR THE DEVELOPMENTAL ORIGINS OF DISEASE AND DISCUSS THE ROLE OF THE EPIGENOTYPE AS A CONTRIBUTING MECHANISM. ENVIRONMENTALLY INDUCED CHANGES IN THE EPIGENOTYPE MIGHT BE KEY PRIMARY EVENTS IN THE DEVELOPMENTAL ORIGINS OF DISEASE, WITH IMPORTANT CLINICAL IMPLICATIONS. 2007 15 2713 25 EXERCISE TRAINING AND EPIGENETIC REGULATION: MULTILEVEL MODIFICATION AND REGULATION OF GENE EXPRESSION. EXERCISE TRAINING ELICITS ACUTE AND ADAPTIVE LONG TERM CHANGES IN HUMAN PHYSIOLOGY THAT MEDIATE THE IMPROVEMENT OF PERFORMANCE AND HEALTH STATE. THE RESPONSES ARE INTEGRATIVE AND ORCHESTRATED BY SEVERAL MECHANISMS, AS GENE EXPRESSION. GENE EXPRESSION IS ESSENTIAL TO CONSTRUCT THE ADAPTATION OF THE BIOLOGICAL SYSTEM TO EXERCISE TRAINING, SINCE THERE ARE MOLECULAR PROCESSES MEDIATING OXIDATIVE AND NON-OXIDATIVE METABOLISM, ANGIOGENESIS, CARDIAC AND SKELETAL MYOFIBER HYPERTROPHY, AND OTHER PROCESSES THAT LEADS TO A GREATER PHYSIOLOGICAL STATUS. EPIGENETIC IS THE FIELD THAT STUDIES ABOUT GENE EXPRESSION CHANGES HERITABLE BY MEIOSIS AND MITOSIS, BY CHANGES IN CHROMATIN AND DNA CONFORMATION, BUT NOT IN DNA SEQUENCE, THAT STUDIES THE REGULATION ON GENE EXPRESSION THAT IS INDEPENDENT OF GENOTYPE. THE FIELD APPROACHES MECHANISMS OF DNA AND CHROMATIN CONFORMATIONAL CHANGES THAT INHIBIT OR INCREASE GENE EXPRESSION AND DETERMINE TISSUE SPECIFIC PATTERN. THE THREE MAJOR STUDIED EPIGENETIC MECHANISMS ARE DNA METHYLATION, HISTONE MODIFICATION, AND REGULATION OF NONCODING RNA-ASSOCIATED GENES. THIS REVIEW ELUCIDATES THESE MECHANISMS, FOCUSING ON THE RELATIONSHIP BETWEEN THEM AND THEIR RELATIONSHIP WITH EXERCISE TRAINING, PHYSICAL PERFORMANCE AND THE ENHANCEMENT OF HEALTH STATUS. ON THIS CHAPTER, WE CLARIFIED THE RELATIONSHIP OF EPIGENETIC MODULATIONS AND THEIR INTIMAL RELATIONSHIP WITH ACUTE AND CHRONIC EFFECT OF EXERCISE TRAINING, CONCENTRATING OUR EFFORT ON SKELETAL MUSCLE, HEART AND VASCULAR RESPONSES, THAT ARE THE MOST RESPONSIVE SYSTEMS AGAINST TO EXERCISE TRAINING AND PLAY CRUCIAL ROLE ON PHYSICAL PERFORMANCE AND IMPROVEMENT OF HEALTH STATE. 2017 16 2235 22 EPIGENETIC MODIFICATIONS, ALCOHOLIC BRAIN AND POTENTIAL DRUG TARGETS. ACUTE AND CHRONIC ALCOHOL EXPOSURE EVIDENTLY INFLUENCES EPIGENETIC CHANGES, BOTH TRANSIENTLY AND PERMANENTLY, AND THESE CHANGES IN TURN INFLUENCE A VARIETY OF CELLS AND ORGAN SYSTEMS THROUGHOUT THE BODY. MANY OF THE ALCOHOL-INDUCED EPIGENETIC MODIFICATIONS CAN CONTRIBUTE TO CELLULAR ADAPTATIONS THAT ULTIMATELY LEAD TO BEHAVIORAL TOLERANCE AND ALCOHOL DEPENDENCE. THE PERSISTENCE OF BEHAVIORAL CHANGES DEMONSTRATES THAT LONG-LASTING CHANGES IN GENE EXPRESSION, WITHIN PARTICULAR REGIONS OF THE BRAIN, MAY CONTRIBUTE IMPORTANTLY TO THE ADDICTION PHENOTYPE. THE RESEARCH ACTIVITIES OVER THE PAST YEARS HAVE DEMONSTRATED A CRUCIAL ROLE OF EPIGENETIC MECHANISMS IN CAUSING LONG LASTING AND TRANSIENT CHANGES IN THE EXPRESSION OF SEVERAL GENES IN DIVERSE TISSUES, INCLUDING BRAIN. THIS HAS STIMULATED RECENT RESEARCH WORK THAT IS AIMED AT CHARACTERIZING THE INFLUENCE OF EPIGENETIC REGULATORY EVENTS IN MEDIATING THE LONG LASTING AND TRANSIENT EFFECTS OF ALCOHOL ABUSE ON THE BRAIN IN HUMANS AND ANIMAL MODELS OF ALCOHOL ADDICTION. IN THIS STUDY, WE UPDATE OUR CURRENT UNDERSTANDING OF THE IMPACT OF ALCOHOL EXPOSURE ON EPIGENETIC MECHANISMS IN THE BRAIN AND REFURBISH THE KNOWLEDGE OF EPIGENETICS IN THE DIRECTION OF NEW DRUGS DEVELOPMENT. 2016 17 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 18 6866 29 [PAIN AND EMOTIONAL DYSREGULATION: CELLULAR MEMORY DUE TO PAIN]. GENETIC FACTORS ARE INVOLVED IN DETERMINANTS FOR THE RISK OF PSYCHIATRIC DISORDERS, AND NEUROLOGICAL AND NEURODEGENERATIVE DISEASES. CHRONIC PAIN STIMULI AND INTENSE PAIN HAVE EFFECTS AT A CELLULAR AND/OR GENE EXPRESSION LEVEL, AND WILL EVENTUALLY INDUCE "CELLULAR MEMORY DUE TO PAIN", WHICH MEANS THAT TISSUE DAMAGE, EVEN IF ONLY TRANSIENT, CAN ELICIT EPIGENETICALLY ABNORMAL TRANSCRIPTION/TRANSLATION AND POST-TRANSLATIONAL MODIFICATION IN RELATED CELLS DEPENDING ON THE DEGREE OR KIND OF INJURY OR ASSOCIATED CONDITIONS. SUCH CELL MEMORY/TRANSFORMATION DUE TO PAIN CAN CAUSE AN ABNORMALITY IN A FUNDAMENTAL INTRACELLULAR RESPONSE, SUCH AS A CHANGE IN THE THREE-DIMENSIONAL STRUCTURE OF DNA, TRANSCRIPTION, OR TRANSLATION. ON THE OTHER HAND, PAIN IS A MULTIDIMENSIONAL EXPERIENCE WITH SENSORY-DISCRIMINATIVE AND MOTIVATIONAL-AFFECTIVE COMPONENTS. RECENT HUMAN BRAIN IMAGING STUDIES HAVE EXAMINED DIFFERENCES IN ACTIVITY IN THE NUCLEUS ACCUMBENS BETWEEN CONTROLS AND PATIENTS WITH CHRONIC PAIN, AND HAVE REVEALED THAT THE NUCLEUS ACCUMBENS PLAYS A ROLE IN PREDICTING THE VALUE OF A NOXIOUS STIMULUS AND ITS OFFSET, AND IN THE CONSEQUENT CHANGES IN THE MOTIVATIONAL STATE. IN THIS REVIEW, WE PROVIDE A VERY BRIEF OVERVIEW OF A COMPREHENSIVE UNDERSTANDING OF CHRONIC PAIN ASSOCIATED WITH EMOTIONAL DYSREGULATION DUE TO TRANSCRIPTIONAL REGULATION, EPIGENETIC MODIFICATION AND MIRNA REGULATION. 2015 19 5410 22 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 20 6715 28 VITAMIN A AND THE EPIGENOME. THE EPIGENETIC PHENOMENA REFER TO HERITABLE CHANGES IN GENE EXPRESSION OTHER THAN THOSE IN THE DNA SEQUENCE, SUCH AS DNA METHYLATION AND HISTONE MODIFICATIONS. MAJOR RESEARCH PROGRESS IN THE LAST FEW YEARS HAS PROVIDED FURTHER PROOF THAT ENVIRONMENTAL FACTORS, INCLUDING DIET AND NUTRITION, CAN INFLUENCE PHYSIOLOGIC AND PATHOLOGIC PROCESSES THROUGH EPIGENETIC ALTERATIONS, WHICH IN TURN INFLUENCE GENE EXPRESSION. THIS INFLUENCE IS TERMED NUTRITIONAL EPIGENETICS, AND ONE PROMINENT EXAMPLE IS THE REGULATION OF GENE TRANSCRIPTION BY VITAMIN A THROUGH INTERACTION TO ITS NUCLEAR RECEPTOR. VITAMIN A IS CRITICAL THROUGHOUT LIFE. TOGETHER WITH ITS DERIVATIVES, IT REGULATES DIVERSE PROCESSES INCLUDING REPRODUCTION, EMBRYOGENESIS, VISION, GROWTH, CELLULAR DIFFERENTIATION AND PROLIFERATION, MAINTENANCE OF EPITHELIAL CELLULAR INTEGRITY AND IMMUNE FUNCTION. HERE WE REVIEW THE EPIGENETIC ROLE OF VITAMIN A IN CANCER, STEM CELLS DIFFERENTIATION, PROLIFERATION, AND IMMUNITY. THE DATA PRESENTED HERE SHOW THAT RETINOIC ACID IS A POTENT AGENT CAPABLE OF INDUCING ALTERATIONS IN EPIGENETIC MODIFICATIONS THAT PRODUCE VARIOUS EFFECTS ON THE PHENOTYPE. MEDICAL BENEFITS OF VITAMIN A AS AN EPIGENETIC MODULATOR, ESPECIALLY WITH RESPECT TO ITS CHRONIC USE AS NUTRITIONAL SUPPLEMENT, SHOULD RELY ON OUR FURTHER UNDERSTANDING OF ITS EPIGENETIC EFFECTS DURING HEALTH AND DISEASE, AS WELL AS THROUGH DIFFERENT GENERATIONS. 2017