1 874 90 CHRONIC ALLERGY SIGNALING: IS IT ALL STRESSED-OUT MITOCHONDRIA? ALLERGIC DISEASES IN GENERAL, AND CHRONIC ALLERGIC INFLAMMATION IN PARTICULAR, ARE ON THE RISE IN THE UNITED STATES AND OTHER DEVELOPED COUNTRIES. THE IDEA OF CHRONIC ALLERGIC DISEASE AS A CHRONIC TYPE 2 IMMUNE RESPONSE HAS BEEN AROUND FOR SEVERAL DECADES. HOWEVER, DATA SUGGEST THAT OTHER MECHANISMS MAY BE IMPORTANT IN CHRONIC DISEASE. THEREFORE, WE BELIEVE IT IS TIME FOR A PARADIGM SHIFT IN UNDERSTANDING THE MECHANISTIC CAUSES OF DISEASE SYMPTOMS IN THESE DISEASES. IN THIS REVIEW, WE HAVE AVOIDED THE CLASSIC CANONICAL PATHWAYS AND FOCUSED ON THE EMERGING IDEA THAT OXIDATIVE STRESS, CHANGES IN IMMUNO-METABOLISM, MITOCHONDRIAL DYSFUNCTION, AND EPIGENETIC CHANGES (PARTICULARLY MICRORNA PROFILE) MAY BE WORKING CONCURRENTLY OR SYNERGISTICALLY TO POTENTIATE ALLERGIC DISEASE SYMPTOMS. FURTHERMORE, WE HAVE ADDRESSED HOW THE EPIDEMIC OF OBESITY EXACERBATES ALLERGIC DISEASE VIA THE DYSREGULATION OF THE AFOREMENTIONED FACTORS. 2022 2 4273 32 MICROBIOTA AND EPIGENETICS: HEALTH IMPACT. EPIGENETIC CHANGES ASSOCIATED WITH DISEASE DEVELOPMENT AND PROGRESSIONS ARE OF INCREASING IMPORTANCE BECAUSE OF THEIR POTENTIAL DIAGNOSTIC AND THERAPEUTIC APPLICATIONS. SEVERAL EPIGENETIC CHANGES ASSOCIATED WITH CHRONIC METABOLIC DISORDERS HAVE BEEN STUDIED IN VARIOUS DISEASES. EPIGENETIC CHANGES ARE MOSTLY MODULATED BY ENVIRONMENTAL FACTORS, INCLUDING THE HUMAN MICROBIOTA LIVING IN DIFFERENT PARTS OF OUR BODIES. THE MICROBIAL STRUCTURAL COMPONENTS AND THE MICROBIALLY DERIVED METABOLITES DIRECTLY INTERACT WITH HOST CELLS, THEREBY MAINTAINING HOMEOSTASIS. MICROBIOME DYSBIOSIS, ON THE OTHER HAND, IS KNOWN TO PRODUCE ELEVATED LEVELS OF DISEASE-LINKED METABOLITES, WHICH MAY DIRECTLY AFFECT A HOST METABOLIC PATHWAY OR INDUCE EPIGENETIC CHANGES THAT CAN LEAD TO DISEASE DEVELOPMENT. DESPITE THEIR IMPORTANT ROLE IN HOST PHYSIOLOGY AND SIGNAL TRANSDUCTION, THERE HAS BEEN LITTLE RESEARCH INTO THE MECHANICS AND PATHWAYS ASSOCIATED WITH EPIGENETIC MODIFICATIONS. THIS CHAPTER FOCUSES ON THE RELATIONSHIP BETWEEN MICROBES AND THEIR EPIGENETIC EFFECTS IN DISEASED PATHOLOGY, AS WELL AS ON THE REGULATION AND METABOLISM OF THE DIETARY OPTIONS AVAILABLE TO THE MICROBES. FURTHERMORE, THIS CHAPTER ALSO PROVIDES A PROSPECTIVE LINK BETWEEN THESE TWO IMPORTANT PHENOMENA, TERMED "MICROBIOME AND EPIGENETICS." 2023 3 3404 29 HOW EPIGENETICS IMPACTS ON HUMAN DISEASES. EPIGENETICS IS A RAPIDLY GROWING FIELD OF BIOLOGY THAT STUDIES THE CHANGES IN GENE EXPRESSION THAT ARE NOT DUE TO ALTERATIONS IN THE DNA SEQUENCE BUT RATHER THE CHEMICAL MODIFICATIONS OF DNA AND ITS ASSOCIATED PROTEINS. EPIGENETIC MECHANISMS CAN PROFOUNDLY INFLUENCE GENE EXPRESSION, CELL DIFFERENTIATION, TISSUE DEVELOPMENT, AND DISEASE SUSCEPTIBILITY. UNDERSTANDING EPIGENETIC CHANGES IS ESSENTIAL TO ELUCIDATE THE MECHANISMS UNDERLYING THE INCREASINGLY RECOGNIZED ROLE OF ENVIRONMENTAL AND LIFESTYLE FACTORS IN HEALTH AND DISEASE AND THE INTERGENERATIONAL TRANSMISSION OF PHENOTYPES. RECENT STUDIES SUGGEST EPIGENETICS MAY BE CRITICAL IN VARIOUS DISEASES, FROM CARDIOVASCULAR DISEASE AND CANCER TO NEURODEVELOPMENTAL AND NEURODEGENERATIVE DISORDERS. EPIGENETIC MODIFICATIONS ARE POTENTIALLY REVERSIBLE AND COULD PROVIDE NEW THERAPEUTIC AVENUES FOR TREATING THESE DISEASES USING EPIGENETIC MODULATORS. MOREOVER, EPIGENETICS PROVIDE INSIGHT INTO DISEASE PATHOGENESIS AND BIOMARKERS FOR DISEASE DIAGNOSIS AND RISK STRATIFICATION. NEVERTHELESS, EPIGENETIC INTERVENTIONS HAVE THE POTENTIAL FOR UNINTENDED CONSEQUENCES AND MAY POTENTIALLY LEAD TO INCREASED RISKS OF UNEXPECTED OUTCOMES, SUCH AS ADVERSE DRUG REACTIONS, DEVELOPMENTAL ABNORMALITIES, AND CANCER. THEREFORE, RIGOROUS STUDIES ARE ESSENTIAL TO MINIMIZE THE RISKS ASSOCIATED WITH EPIGENETIC THERAPIES AND TO DEVELOP SAFE AND EFFECTIVE INTERVENTIONS FOR IMPROVING HUMAN HEALTH. THIS ARTICLE PROVIDES A SYNTHETIC AND HISTORICAL VIEW OF THE ORIGIN OF EPIGENETICS AND SOME OF THE MOST RELEVANT ACHIEVEMENTS. 2023 4 2333 29 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 5 6034 35 THE CHALLENGE BY MULTIPLE ENVIRONMENTAL AND BIOLOGICAL FACTORS INDUCE INFLAMMATION IN AGING: THEIR ROLE IN THE PROMOTION OF CHRONIC DISEASE. THE AGING PROCESS IS DRIVEN BY MULTIPLE MECHANISMS THAT LEAD TO CHANGES IN ENERGY PRODUCTION, OXIDATIVE STRESS, HOMEOSTATIC DYSREGULATION AND EVENTUALLY TO LOSS OF FUNCTIONALITY AND INCREASED DISEASE SUSCEPTIBILITY. MOST AGED INDIVIDUALS DEVELOP CHRONIC LOW-GRADE INFLAMMATION, WHICH IS AN IMPORTANT RISK FACTOR FOR MORBIDITY, PHYSICAL AND COGNITIVE IMPAIRMENT, FRAILTY, AND DEATH. AT ANY AGE, CHRONIC INFLAMMATORY DISEASES ARE MAJOR CAUSES OF MORBIMORTALITY, AFFECTING UP TO 5-8% OF THE POPULATION OF INDUSTRIALIZED COUNTRIES. SEVERAL ENVIRONMENTAL FACTORS CAN PLAY AN IMPORTANT ROLE FOR MODIFYING THE INFLAMMATORY STATE. GENETICS ACCOUNTS FOR ONLY A SMALL FRACTION OF CHRONIC-INFLAMMATORY DISEASES, WHEREAS ENVIRONMENTAL FACTORS APPEAR TO PARTICIPATE, EITHER WITH A CAUSATIVE OR A PROMOTIONAL ROLE IN 50% TO 75% OF PATIENTS. SEVERAL OF THOSE CHANGES DEPEND ON EPIGENETIC CHANGES THAT WILL FURTHER MODIFY THE INDIVIDUAL RESPONSE TO ADDITIONAL STIMULI. THE INTERACTION BETWEEN INFLAMMATION AND THE ENVIRONMENT OFFERS IMPORTANT INSIGHTS ON AGING AND HEALTH. THESE CONDITIONS, OFTEN DEPENDING ON THE INDIVIDUAL'S SEX, APPEAR TO LEAD TO DECREASED LONGEVITY AND PHYSICAL AND COGNITIVE DECLINE. IN ADDITION TO BIOLOGICAL FACTORS, THE ENVIRONMENT IS ALSO INVOLVED IN THE GENERATION OF PSYCHOLOGICAL AND SOCIAL CONTEXT LEADING TO STRESS. POOR PSYCHOLOGICAL ENVIRONMENTS AND OTHER SOURCES OF STRESS ALSO RESULT IN INCREASED INFLAMMATION. HOWEVER, THE MECHANISMS UNDERLYING THE ROLE OF ENVIRONMENTAL AND PSYCHOSOCIAL FACTORS AND NUTRITION ON THE REGULATION OF INFLAMMATION, AND HOW THE RESPONSE ELICITED FOR THOSE FACTORS INTERACT AMONG THEM, ARE POORLY UNDERSTOOD. WHEREAS CERTAIN DELETERIOUS ENVIRONMENTAL FACTORS RESULT IN THE GENERATION OF OXIDATIVE STRESS DRIVEN BY AN INCREASED PRODUCTION OF REACTIVE OXYGEN AND NITROGEN SPECIES, ENDOPLASMIC RETICULUM STRESS, AND INFLAMMATION, OTHER FACTORS, INCLUDING NUTRITION (POLYUNSATURATED FATTY ACIDS) AND BEHAVIORAL FACTORS (EXERCISE) CONFER PROTECTION AGAINST INFLAMMATION, OXIDATIVE AND ENDOPLASMIC RETICULUM STRESS, AND THUS AMELIORATE THEIR DELETERIOUS EFFECT. HERE, WE DISCUSS PROCESSES AND MECHANISMS OF INFLAMMATION ASSOCIATED WITH ENVIRONMENTAL FACTORS AND BEHAVIOR, THEIR LINKS TO SEX AND GENDER, AND THEIR OVERALL IMPACT ON AGING. 2020 6 6735 31 WHAT HAVE MECHANISTIC STUDIES TAUGHT US ABOUT CHILDHOOD ASTHMA? CHILDHOOD ASTHMA IS A CHRONIC HETEROGENEOUS SYNDROME CONSISTING OF DIFFERENT DISEASE ENTITIES OR PHENOTYPES. THE IMMUNOLOGIC AND CELLULAR PROCESSES THAT OCCUR DURING ASTHMA DEVELOPMENT ARE STILL NOT FULLY UNDERSTOOD BUT REPRESENT DISTINCT ENDOTYPES. MECHANISTIC STUDIES HAVE EXAMINED THE ROLE OF GENE EXPRESSION, PROTEIN LEVELS, AND CELL TYPES IN EARLY LIFE DEVELOPMENT AND THE MANIFESTATION OF ASTHMA, MANY UNDER THE INFLUENCE OF ENVIRONMENTAL STIMULI, WHICH CAN BE BOTH PROTECTIVE AND RISK FACTORS FOR ASTHMA. GENETIC VARIANTS CAN REGULATE GENE EXPRESSION, CONTROLLED PARTLY BY DIFFERENT EPIGENETIC MECHANISMS. IN ADDITION, ENVIRONMENTAL FACTORS, SUCH AS LIVING SPACE, NUTRITION, AND SMOKING, CAN CONTRIBUTE TO THESE MECHANISMS. ALL OF THESE FACTORS PRODUCE MODIFICATIONS IN GENE EXPRESSION THAT CAN ALTER THE DEVELOPMENT AND FUNCTION OF IMMUNE AND EPITHELIAL CELLS AND SUBSEQUENTLY DIFFERENT TRAJECTORIES OF CHILDHOOD ASTHMA. THESE EARLY CHANGES IN A PARTIALLY IMMATURE IMMUNE SYSTEM CAN HAVE DRAMATIC EFFECTS (E.G., CAUSING DYSREGULATION), WHICH IN TURN CONTRIBUTE TO DIFFERENT DISEASE ENDOTYPES AND MAY HELP TO EXPLAIN DIFFERENTIAL RESPONSIVENESS TO ASTHMA TREATMENT. IN THIS REVIEW, WE SUMMARIZE PUBLISHED STUDIES THAT HAVE AIMED TO UNCOVER DISTINCT MECHANISMS IN CHILDHOOD ASTHMA, CONSIDERING GENETICS, EPIGENETICS, AND ENVIRONMENT. MOREOVER, A DISCUSSION OF NEW, POWERFUL TOOLS FOR SINGLE-CELL IMMUNOLOGIC ASSAYS FOR PHENOTYPIC AND FUNCTIONAL ANALYSIS IS INCLUDED, WHICH PROMISE NEW MECHANISTIC INSIGHTS INTO CHILDHOOD ASTHMA DEVELOPMENT AND THERAPEUTIC AND PREVENTIVE STRATEGIES. 2023 7 5552 31 ROLE OF EPIGENETICS IN THE PATHOGENESIS OF ASTHMA. ASTHMA IS A COMPLEX, HETEROGENEOUS AND CHRONIC AIRWAY INFLAMMATORY DISEASE WITH DIFFERENT CLINICAL PHENOTYPES CAUSED BY DIVERSE TRIGGERS AND PATHOPHYSIOLOGICAL MECHANISMS. ASTHMA HERITABILITY HAS BEEN ESTABLISHED IN MANY GENETIC STUDIES BUT IT IS EVIDENT THAT ONLY GENETIC ELEMENTS ARE NOT RESPONSIBLE FOR THE DEVELOPMENT OF ASTHMA. INCREASING RATE OF ASTHMA INCIDENCE DURING PAST DECADES HAS IMPLICATED THE ROLE OF EPIGENETICS IN DEVELOPMENT OF ASTHMA. ENVIRONMENTAL FACTORS PERFORM AS INITIATOR SIGNALS THROUGH EPIGENETIC MECHANISMS. THREE EPIGENETIC MECHANISMS HAVE BEEN IDENTIFIED, INCLUDING DNA METHYLATION, HISTONE MODIFICATIONS, AND SMALL NONCODING RNAS. THESE MECHANISMS REGULATE THE IMMUNE RESPONSES AND INFLAMMATORY GENES EXPRESSION IN ASTHMA AND ALLERGY. THIS REVIEW EXPLAINS THE ROLE OF EPIGENETIC MODIFICATIONS IN CONTROLLING TH2 RESPONSE AND IGE PRODUCTION IN ASTHMA AND ALSO BRIEFLY OVERVIEWS THE ROLE OF ENVIRONMENTAL FACTORS SUCH AS POLLUTIONS, ALLERGENS, PRENATAL EXPOSURES AND DIET IN DEVELOPING ASTHMA. RECOGNIZING ENVIRONMENTAL RISK FACTORS AND THEIR EFFECTS ON EPIGENETIC MECHANISMS WOULD BE OF GREAT INTEREST FOR PROGNOSTIC AND PREVENTIVE ASPECT IN TREATMENT OF ASTHMA. 2017 8 5069 19 PHYSICAL ACTIVITY IN THE PREVENTION OF HUMAN DISEASES: ROLE OF EPIGENETIC MODIFICATIONS. EPIGENETIC MODIFICATION REFERS TO HERITABLE CHANGES IN GENE FUNCTION THAT CANNOT BE EXPLAINED BY ALTERATIONS IN THE DNA SEQUENCE. THE CURRENT LITERATURE CLEARLY DEMONSTRATES THAT THE EPIGENETIC RESPONSE IS HIGHLY DYNAMIC AND INFLUENCED BY DIFFERENT BIOLOGICAL AND ENVIRONMENTAL FACTORS SUCH AS AGING, NUTRIENT AVAILABILITY AND PHYSICAL EXERCISE. AS SUCH, IT IS WELL ACCEPTED THAT PHYSICAL ACTIVITY AND EXERCISE CAN MODULATE GENE EXPRESSION THROUGH EPIGENETIC ALTERNATIONS ALTHOUGH THE TYPE AND DURATION OF EXERCISE ELICITING SPECIFIC EPIGENETIC EFFECTS THAT CAN RESULT IN HEALTH BENEFITS AND PREVENT CHRONIC DISEASES REMAINS TO BE DETERMINED. THIS REVIEW HIGHLIGHTS THE MOST SIGNIFICANT FINDINGS FROM EPIGENETIC STUDIES INVOLVING PHYSICAL ACTIVITY/EXERCISE INTERVENTIONS KNOWN TO BENEFIT CHRONIC DISEASES SUCH AS METABOLIC SYNDROME, DIABETES, CANCER, CARDIOVASCULAR AND NEURODEGENERATIVE DISEASES. 2017 9 6812 26 [EPIGENETICS, INTERFACE BETWEEN ENVIRONMENT AND GENES: ROLE IN COMPLEX DISEASES]. EPIGENETICS IS THE STUDY OF HERITABLE CHANGES IN GENE EXPRESSION OR CELLULAR PHENOTYPE CAUSED BY MECHANISMS OTHER THAN CHANGES IN THE UNDERLYING DNA SEQUENCE. EPIGENETICS IS ONE OF THE MAJOR MECHANISMS EXPLAINING THE "DEVELOPMENTAL ORIGIN OF HEALTH AND DISEASES" (DOHAD). BESIDES GENETIC BACKGROUND INHERITED FROM PARENTS, WHICH CONFERS SUSCEPTIBILITY TO CERTAIN PATHOLOGIES, EPIGENETIC CHANGES CONSTITUTE THE MEMORY OF PREVIOUS EVENTS, EITHER POSITIVE OR NEGATIVE, ALONG THE LIFE CYCLE, INCLUDING AT THE IN UTERO STAGE. THE LATER EXPOSITION TO HOSTILE ENVIRONMENT MAY REVEAL SUCH SUSCEPTIBILITY, WITH THE DEVELOPMENT OF VARIOUS PATHOLOGIES, AMONG THEM NUMEROUS CHRONIC COMPLEX DISEASES. THE DEMONSTRATION OF SUCH A SEQUENCE OF EVENTS HAS BEEN SHOWN FOR METABOLIC DISEASES AS OBESITY, METABOLIC SYNDROME AND TYPE 2 DIABETES, CARDIOVASCULAR DISEASE AND CANCER. IN CONTRAST TO GENETIC PREDISPOSITION, WHICH IS IRREVERSIBLE, EPIGENETIC CHANGES ARE POTENTIALLY REVERSIBLE, THUS GIVING TARGETS NOT ONLY FOR PREVENTION, BUT POSSIBLY ALSO FOR THE TREATMENT OF CERTAIN COMPLEX DISEASES. 2012 10 2570 24 EPIGENETICS OF CHRONIC INFLAMMATORY DISEASES. CHRONIC, NONCOMMUNICABLE, AND INFLAMMATION-ASSOCIATED DISEASES REMAIN THE LARGEST CAUSE OF MORBIDITY AND MORTALITY GLOBALLY AND WITHIN THE UNITED STATES. THIS IS MAINLY DUE TO OUR LIMITED UNDERSTANDING OF THE MOLECULAR MECHANISMS THAT UNDERLIE THESE COMPLEX PATHOLOGIES. THE AVAILABLE EVIDENCE INDICATES THAT STUDIES OF EPIGENETICS (TRADITIONALLY DEFINED AS THE HERITABLE CHANGES TO GENE EXPRESSION THAT ARE INDEPENDENT OF CHANGES TO DNA) ARE SIGNIFICANTLY ADVANCING OUR KNOWLEDGE OF THESE INFLAMMATORY CONDITIONS. THIS REVIEW WILL FOCUS ON EPIGENETIC STUDIES OF THREE DISEASES, THAT ARE AMONG THE MOST BURDENSOME GLOBALLY: CARDIOVASCULAR DISEASE, THE NUMBER ONE CAUSE OF DEATHS WORLDWIDE, TYPE 2 DIABETES AND, ALZHEIMER'S DISEASE. THE CURRENT STATUS OF EPIGENETIC RESEARCH, INCLUDING THE ABILITY TO PREDICT DISEASE RISK, AND KEY PATHOPHYSIOLOGICAL DEFECTS ARE DISCUSSED. THE SIGNIFICANCE OF DEFINING THE CONTRIBUTION OF EPIGENETIC DEFECTS TO NONRESOLVING INFLAMMATION AND AGING, EACH ASSOCIATED WITH THESE DISEASES, IS HIGHLIGHTED, AS THESE ARE LIKELY TO PROVIDE NEW INSIGHTS INTO INFLAMMATORY DISEASE PATHOGENESIS. 2019 11 6287 36 THE POTENTIAL ROLE OF ENVIRONMENTAL FACTORS IN MODULATING MITOCHONDRIAL DNA EPIGENETIC MARKS. MANY STUDIES IMPLICATE MITOCHONDRIAL DYSFUNCTION IN THE DEVELOPMENT AND PROGRESSION OF NUMEROUS CHRONIC DISEASES. MITOCHONDRIA ARE RESPONSIBLE FOR MOST CELLULAR ENERGY PRODUCTION, AND UNLIKE OTHER CYTOPLASMIC ORGANELLES, MITOCHONDRIA CONTAIN THEIR OWN GENOME. MOST RESEARCH TO DATE, THROUGH INVESTIGATING MITOCHONDRIAL DNA COPY NUMBER, HAS FOCUSED ON LARGER STRUCTURAL CHANGES OR ALTERATIONS TO THE ENTIRE MITOCHONDRIAL GENOME AND THEIR ROLE IN HUMAN DISEASE. USING THESE METHODS, MITOCHONDRIAL DYSFUNCTION HAS BEEN LINKED TO CANCERS, CARDIOVASCULAR DISEASE, AND METABOLIC HEALTH. HOWEVER, LIKE THE NUCLEAR GENOME, THE MITOCHONDRIAL GENOME MAY EXPERIENCE EPIGENETIC ALTERATIONS, INCLUDING DNA METHYLATION THAT MAY PARTIALLY EXPLAIN SOME OF THE HEALTH EFFECTS OF VARIOUS EXPOSURES. RECENTLY, THERE HAS BEEN A MOVEMENT TO UNDERSTAND HUMAN HEALTH AND DISEASE WITHIN THE CONTEXT OF THE EXPOSOME, WHICH AIMS TO DESCRIBE AND QUANTIFY THE ENTIRETY OF ALL EXPOSURES PEOPLE ENCOUNTER THROUGHOUT THEIR LIVES. THESE INCLUDE, AMONG OTHERS, ENVIRONMENTAL POLLUTANTS, OCCUPATIONAL EXPOSURES, HEAVY METALS, AND LIFESTYLE AND BEHAVIORAL FACTORS. IN THIS CHAPTER, WE SUMMARIZE THE CURRENT RESEARCH ON MITOCHONDRIA AND HUMAN HEALTH, PROVIDE AN OVERVIEW OF THE CURRENT KNOWLEDGE ON MITOCHONDRIAL EPIGENETICS, AND DESCRIBE THE EXPERIMENTAL AND EPIDEMIOLOGIC STUDIES THAT HAVE INVESTIGATED PARTICULAR EXPOSURES AND THEIR RELATIONSHIPS WITH MITOCHONDRIAL EPIGENETIC MODIFICATIONS. WE CONCLUDE THE CHAPTER WITH SUGGESTIONS FOR FUTURE DIRECTIONS IN EPIDEMIOLOGIC AND EXPERIMENTAL RESEARCH THAT IS NEEDED TO ADVANCE THE GROWING FIELD OF MITOCHONDRIAL EPIGENETICS. 2023 12 2577 28 EPIGENETICS OF INFLAMMATION, MATERNAL INFECTION, AND NUTRITION. STUDIES HAVE DEMONSTRATED THAT EPIGENETIC CHANGES SUCH AS DNA METHYLATION, HISTONE MODIFICATION, AND CHROMATIN REMODELING ARE LINKED TO AN INCREASED INFLAMMATORY RESPONSE AS WELL AS INCREASED RISK OF CHRONIC DISEASE DEVELOPMENT. A FEW STUDIES HAVE BEGUN TO INVESTIGATE WHETHER DIETARY NUTRIENTS PLAY A BENEFICIAL ROLE BY MODIFYING OR REVERSING EPIGENETICALLY INDUCED INFLAMMATION. RESULTS OF THESE STUDIES SHOW THAT NUTRIENTS MODIFY EPIGENETIC PATHWAYS. HOWEVER, LITTLE IS KNOWN ABOUT HOW NUTRIENTS MODULATE INFLAMMATION BY REGULATING IMMUNE CELL FUNCTION AND/OR IMMUNE CELL DIFFERENTIATION VIA EPIGENETIC PATHWAYS. THIS OVERVIEW WILL PROVIDE INFORMATION ABOUT THE CURRENT UNDERSTANDING OF THE ROLE OF NUTRIENTS IN THE EPIGENETIC CONTROL MECHANISMS OF IMMUNE FUNCTION. 2015 13 2154 33 EPIGENETIC MECHANISMS AND KIDNEY DISEASES. IN RECENT YEARS, MOLECULAR RESEARCH HAS BROUGHT TO LIGHT A SERIES OF MECHANISMS INVOLVED IN THE REGULATION OF GENE FUNCTION WITHOUT ALTERING THE DNA SEQUENCE. THESE MECHANISMS ARE DESCRIBED WITH THE TERM "EPIGENETICS" AND INCLUDE MODIFICATIONS IN THE STRUCTURE OF THE HUMAN GENOME, LEADING TO HERITABLE AND POTENTIALLY REVERSIBLE CHANGES IN GENE EXPRESSION. THERE IS NOW INCREASING EVIDENCE SUGGESTING THAT SEVERAL CHARACTERISTIC FEATURES OF CHRONIC KIDNEY DISEASE SUCH AS HYPERHOMOCYSTEINEMIA, SUBCLINICAL INFLAMMATION, INCREASED OXIDATIVE STRESS AND OTHERS MAY AFFECT THE HUMAN EPIGENOME. IN ADDITION, ANIMAL STUDIES HAVE SUGGESTED A POSSIBLE LINK BETWEEN NUTRITION AND ENVIRONMENTAL EXPOSURE DURING THE PERICONCEPTIONAL PERIOD AND EPIGENETIC CHANGES IN THE EXPRESSION OF MAJOR GENES IMPLICATED IN KIDNEY ORGANOGENESIS; THESE CHANGES RESULT IN A DIMINISHED NUMBER OF NEPHRONS IN THE DEVELOPING KIDNEY, WHICH PREDISPOSES TO AN INCREASED RISK FOR HYPERTENSION AND CHRONIC KIDNEY DISEASE IN FUTURE LIFE. THE UNDERSTANDING OF THE ROLE OF EPIGENETIC PHENOMENA IN THE PATHOGENESIS OF CHRONIC KIDNEY DISEASE OPENS NEW AVENUES FOR FUTURE THERAPEUTIC STRATEGIES, THROUGH THE DEVELOPMENT OF PHARMACEUTICAL AGENTS THAT TARGET DIRECTLY WITH THE CHANGES IN THE HUMAN EPIGENOME. SUCH EPIGENETIC DRUGS ARE ALREADY IN CLINICAL USE FOR THE TREATMENT OF CANCER AS WELL AS UNDER INVESTIGATION FOR THE USE IN OTHER DISEASES. THIS REVIEW WILL SUMMARIZE THE EXISTING DATA ON THE LINK BETWEEN EPIGENETIC MECHANISMS AND CHRONIC UREMIC MILIEU, AS WELL AS THE PROMISING RESULTS OF ONGOING RESEARCH IN THE FIELD OF EPIGENETIC DRUGS THAT COULD REPRESENT ADDITIONAL OPTIONS IN OUR THERAPEUTIC ARMAMENTARIUM FOR PATIENTS WITH CHRONIC KIDNEY DISEASE. 2011 14 1871 33 EMERGING ROLE OF EPIGENETICS IN EXPLAINING RELATIONSHIP OF PERIODONTITIS AND CARDIOVASCULAR DISEASES. CARDIOVASCULAR DISEASES SUCH AS ISCHEMIC HEART DISEASES OR STROKE ARE AMONG THE LEADING CAUSE OF DEATHS GLOBALLY, AND EVIDENCE SUGGESTS THAT THESE DISEASES ARE MODULATED BY A MULTIFACTORIAL AND COMPLEX INTERPLAY OF GENETIC, ENVIRONMENTAL, AND LIFESTYLE FACTORS. GENETIC PREDISPOSITION AND CHRONIC EXPOSURE TO MODIFIABLE RISK FACTORS HAVE BEEN EXPLORED TO BE INVOLVED IN THE PATHOPHYSIOLOGY OF CVD. ENVIRONMENTAL FACTORS CONTRIBUTE TO AN INDIVIDUAL'S PROPENSITY TO DEVELOP MAJOR CARDIOVASCULAR RISK FACTORS THROUGH EPIGENETIC MODIFICATIONS OF DNA AND HISTONES VIA MIRNA REGULATION OF PROTEIN TRANSLATION THAT ARE TYPES OF EPIGENETIC MECHANISMS AND PARTICIPATE IN DISEASE DEVELOPMENT. PERIODONTAL DISEASE (PD) IS ONE OF THE MOST COMMON ORAL DISEASES IN HUMANS THAT IS CHARACTERIZED BY LOW-GRADE INFLAMMATION AND HAS BEEN SHOWN TO INCREASE THE RISK OF CVDS. RISK FACTORS INVOLVED IN PD AND CVD ARE DETERMINED BOTH GENETICALLY AND BEHAVIORALLY. PERIODONTAL DISEASES SUCH AS CHRONIC INFLAMMATION PROMOTE DNA METHYLATION. EPIGENETIC MODIFICATIONS INVOLVED IN THE INITIATION AND PROGRESSION OF ATHEROSCLEROSIS PLAY AN ESSENTIAL ROLE IN PLAQUE DEVELOPMENT AND VULNERABILITY. EPIGENETICS HAS OPENED A NEW WORLD TO UNDERSTAND AND MANAGE HUMAN DISEASES, INCLUDING CVDS AND PERIODONTAL DISEASES. GENETIC MEDICINE HAS STARTED A NEW ERA OF EPIGENETICS TO OVERCOME HUMAN DISEASES WITH VARIOUS NEW METHODOLOGY. EPIGENETIC PROFILING MAY AID IN BETTER DIAGNOSIS AND STRATIFICATION OF PATIENTS SHOWING POTENTIAL PREDISPOSED STATES FOR DISEASE. A BETTER UNDERSTANDING OF THE EXACT REGULATORY MECHANISMS OF EPIGENETIC PATHWAYS DRIVING INFLAMMATION IS SLOWLY EMERGING AND WILL AID IN DEVELOPING NOVEL TOOLS FOR THE TREATMENT OF DISEASE. 2021 15 6183 32 THE IMPACT OF ENVIRONMENTAL FACTORS IN INFLUENCING EPIGENETICS RELATED TO OXIDATIVE STATES IN THE CARDIOVASCULAR SYSTEM. OXIDATIVE STATES EXERT A SIGNIFICANT INFLUENCE ON A WIDE RANGE OF BIOLOGICAL AND MOLECULAR PROCESSES AND FUNCTIONS. WHEN THEIR BALANCE IS SHIFTED TOWARDS ENHANCED AMOUNTS OF FREE RADICALS, PATHOLOGICAL PHENOMENA CAN OCCUR, AS THE GENERATION OF REACTIVE OXYGEN SPECIES (ROS) IN TISSUE MICROENVIRONMENT OR IN THE SYSTEMIC CIRCULATION CAN BE DETRIMENTAL. EPIDEMIC CHRONIC DISEASES OF WESTERN SOCIETIES, SUCH AS CARDIOVASCULAR DISEASE, OBESITY, AND DIABETES CORRELATE WITH THE IMBALANCE OF REDOX HOMEOSTASIS. CURRENT ADVANCES IN OUR UNDERSTANDING OF EPIGENETICS HAVE REVEALED A PARALLEL SCENARIO SHOWING THE INFLUENCE OF OXIDATIVE STRESS AS A MAJOR REGULATOR OF EPIGENETIC GENE REGULATION VIA MODIFICATION OF DNA METHYLATION, HISTONES, AND MICRORNAS. THIS HAS PROVIDED BOTH THE BIOLOGICAL LINK AND A POTENTIAL MOLECULAR EXPLANATION BETWEEN OXIDATIVE STRESS AND CARDIOVASCULAR/METABOLIC PHENOMENA. ACCORDINGLY, IN THIS REVIEW, WE WILL PROVIDE CURRENT INSIGHTS ON THE PHYSIOLOGICAL AND PATHOLOGICAL IMPACT OF CHANGES IN OXIDATIVE STATES ON CARDIOVASCULAR DISORDERS, BY SPECIFICALLY FOCUSING ON THE INFLUENCE OF EPIGENETIC REGULATION. A SPECIAL EMPHASIS WILL HIGHLIGHT THE EFFECT ON EPIGENETIC REGULATION OF HUMAN'S CURRENT LIFE HABITS, EXTERNAL AND ENVIRONMENTAL FACTORS, INCLUDING FOOD INTAKE, TOBACCO, AIR POLLUTION, AND ANTIOXIDANT-BASED APPROACHES. ADDITIONALLY, THE STRATEGY TO QUANTIFY OXIDATIVE STATES IN HUMANS IN ORDER TO DETERMINE WHICH BIOLOGICAL MARKER COULD BEST MATCH A SUBJECT'S PROFILE WILL BE DISCUSSED. 2017 16 2163 29 EPIGENETIC MECHANISMS IN DIABETIC VASCULAR COMPLICATIONS. THERE HAS BEEN A RAPID INCREASE IN THE INCIDENCE OF DIABETES AS WELL THE ASSOCIATED VASCULAR COMPLICATIONS. BOTH GENETIC AND ENVIRONMENTAL FACTORS HAVE BEEN IMPLICATED IN THESE PATHOLOGIES. INCREASING EVIDENCE SUGGESTS THAT EPIGENETIC FACTORS PLAY A KEY ROLE IN THE COMPLEX INTERPLAY BETWEEN GENES AND THE ENVIRONMENT. ACTIONS OF MAJOR PATHOLOGICAL MEDIATORS OF DIABETES AND ITS COMPLICATIONS SUCH AS HYPERGLYCAEMIA, OXIDANT STRESS, AND INFLAMMATORY FACTORS CAN LEAD TO DYSREGULATED EPIGENETIC MECHANISMS THAT AFFECT CHROMATIN STRUCTURE AND GENE EXPRESSION. FURTHERMORE, PERSISTENCE OF THIS ALTERED STATE OF THE EPIGENOME MAY BE THE UNDERLYING MECHANISM CONTRIBUTING TO A 'METABOLIC MEMORY' THAT RESULTS IN CHRONIC INFLAMMATION AND VASCULAR DYSFUNCTION IN DIABETES EVEN AFTER ACHIEVING GLYCAEMIC CONTROL. FURTHER EXAMINATION OF EPIGENETIC MECHANISMS BY ALSO TAKING ADVANTAGE OF RECENTLY DEVELOPED NEXT-GENERATION SEQUENCING TECHNOLOGIES CAN PROVIDE NOVEL INSIGHTS INTO THE PATHOLOGY OF DIABETES AND ITS COMPLICATIONS AND LEAD TO THE DISCOVERY OF MUCH NEEDED NEW DRUG TARGETS FOR THESE DISEASES. IN THIS REVIEW, WE HIGHLIGHT THE ROLE OF EPIGENETICS IN DIABETES AND ITS VASCULAR COMPLICATIONS, AND RECENT TECHNOLOGICAL ADVANCES THAT HAVE SIGNIFICANTLY ACCELERATED THE FIELD. 2011 17 3706 30 INFLUENCE OF GENETICS ON DISEASE SUSCEPTIBILITY AND PROGRESSION. FOR MANY CHRONIC DISEASES, THE INFLUENCE OF GENETICS IS COMPLEX AND PHENOTYPES DO NOT CONFORM TO SIMPLE MENDELIAN PATTERNS OF INHERITANCE. DISCUSSED HERE ARE TWO TYPES OF GENETIC INFLUENCES ON HEALTHY AGING. THE FIRST INVOLVES VARIATION IN THE GENE SEQUENCE ITSELF AND HOW THIS MAY INFLUENCE DISEASE SUSCEPTIBILITY, PROGRESSION, AND SEVERITY, INTERACTING WITH OTHER RECOGNIZED RISK FACTORS. THE SECOND INVOLVES EPIGENETIC REGULATORY MECHANISMS THAT MAY POTENTIALLY PROVIDE INSIGHT INTO HOW ENVIRONMENTAL INFLUENCES AFFECT THE EXPRESSED GENOME, THUS IMPROVING OUR UNDERSTANDING OF THE GENETIC MECHANISMS UNDERLYING MULTIFACTORIAL DISEASES. THE INTERLEUKIN-1 FAMILY OF CYTOKINES CAN BE USED TO ILLUSTRATE HOW GENETIC SEQUENCE VARIATION MAY AFFECT SUCH DISEASES. THIS CYTOKINE FAMILY PLAYS A KEY ROLE IN MEDIATING INFLAMMATION, WHICH IS NOW UNDERSTOOD TO BE A CENTRAL COMPONENT OF A GROWING NUMBER OF CHRONIC DISEASES. RECENT WORK HAS REVEALED MANY SEQUENCE VARIATIONS IN THE REGULATORY DNA OF GENES ENCODING IMPORTANT MEMBERS OF THE INTERLEUKIN-1 FAMILY, AND THESE VARIATIONS ARE ASSOCIATED WITH DIFFERENTIAL EFFECTS ON THE INFLAMMATORY RESPONSE. THE INTERACTIONS OF ENVIRONMENTAL FACTORS WITH BOTH DNA SEQUENCE VARIATIONS AND EPIGENETIC MODIFICATIONS ARE LIKELY TO DETERMINE THE PHENOTYPES OF MULTIFACTORIAL DISEASES OF AGING AS WELL AS THE PHENOTYPE OF HEALTHY AGING. 2007 18 6288 33 THE POTENTIAL ROLE OF EPIGENETIC MODIFICATIONS ON DIFFERENT FACETS IN THE PERIODONTAL PATHOGENESIS. PERIODONTITIS IS A CHRONIC INFLAMMATORY DISEASE THAT AFFECTS THE SUPPORTING STRUCTURES OF TEETH. IN THE LITERATURE, THE ASSOCIATION BETWEEN THE PATHOGENICITY OF BACTERIA AND ENVIRONMENTAL FACTORS IN THIS REGARD HAVE BEEN EXTENSIVELY EXAMINED. IN THE PRESENT STUDY, WE WILL SHED LIGHT ON THE POTENTIAL ROLE THAT EPIGENETIC CHANGE CAN PLAY ON DIFFERENT FACETS OF ITS PROCESS, MORE PARTICULARLY THE MODIFICATIONS CONCERNING THE GENES INVOLVED IN INFLAMMATION, DEFENSE, AND IMMUNE SYSTEMS. SINCE THE 1960S, THE ROLE OF GENETIC VARIANTS IN THE ONSET AND SEVERITY OF PERIODONTAL DISEASE HAS BEEN WIDELY DEMONSTRATED. THESE MAKE SOME PEOPLE MORE SUSCEPTIBLE TO DEVELOPING IT THAN OTHERS. IT HAS BEEN DOCUMENTED THAT THE WIDE VARIATION IN ITS FREQUENCY FOR VARIOUS RACIAL AND ETHNIC POPULATIONS IS DUE PRIMARILY TO THE COMPLEX INTERPLAY AMONG GENETIC FACTORS WITH THOSE AFFECTING THE ENVIRONMENT AND THE DEMOGRAPHY. IN MOLECULAR BIOLOGY, EPIGENETIC MODIFICATIONS ARE DEFINED AS ANY CHANGE IN THE PROMOTER FOR THE CPG ISLANDS, IN THE STRUCTURE OF THE HISTONE PROTEIN, AS WELL AS POST-TRANSLATIONAL REGULATION BY MICRORNAS (MIRNAS), BEING KNOWN TO CONTRIBUTE TO THE ALTERATION IN GENE EXPRESSION FOR COMPLEX MULTIFACTORIAL DISEASES SUCH AS PERIODONTITIS. THE KEY ROLE OF EPIGENETIC MODIFICATION IS TO UNDERSTAND THE MECHANISM INVOLVED IN THE GENE-ENVIRONMENT INTERACTION, AND THE DEVELOPMENT OF PERIODONTITIS IS NOW THE SUBJECT OF MORE AND MORE STUDIES THAT ATTEMPT TO IDENTIFY WHICH FACTORS ARE STIMULATING IT, BUT ALSO AFFECT THE REDUCED RESPONSE TO THERAPY. 2023 19 6905 24 [THE ROLE OF EPIGENETIC REGULATIONS IN EARLY CHILDHOOD DISEASES]. WITH THE ACCEPTANCE OF "THE DEVELOPMENTAL ORIGINS OF HEALTH AND DISEASE" CONCEPT IN THE 1990S, IT BECAME CLEAR THAT EPIGENETIC INHERITANCE, WHICH DO NOT INVOLVE CHANGES IN THE DNA SEQUENCE HAS IMPORTANT ROLE IN THE PATHOGENESIS OF DISEASES. EPIGENETIC REGULATION SERVES THE ADAPTATION TO THE CHANGING ENVIRONMENT AND MAINTAINS THE REPRODUCTIVE FITNESS EVEN ON THE DRAWBACK OF INCREASED RISK OF DISEASES IN LATER LIFE. THE ROLE OF EPIGENETIC MECHANISMS IN CHRONIC NON-COMMUNICABLE DISEASES HAS BEEN WELL ESTABLISHED. RECENT STUDIES HAVE REVEALED THAT EPIGENETIC CHANGES HAVE ALSO CAUSAL ROLE IN CERTAIN PEDIATRIC DISEASES. THE REVIEW EVALUATES THE RECENT EPIGENETIC FINDINGS IN THE PATHOMECHANISM OF COMMON PEDIATRIC DISEASES. THE WIDE RANGE AND LONG-LASTING DURATION OF EPIGENETIC REGULATIONS GIVE IMPORTANCE TO THE SUBJECT. METHODS ARE ALREADY AVAILABLE TO EVALUATE A PART OF THE EPIGENETIC CHANGES IN THE CLINICAL PRACTICE, PRESENTLY AIMING PRIMARILY THE ESTIMATION OF THE DISEASE RISK OR DEFINITION OF DIAGNOSIS. FURTHERMORE, THERE ARE ALREADY AVAILABLE LIMITED MEANS TO INFLUENCE THE EPIGENETIC REGULATION. 2019 20 2282 26 EPIGENETIC REGULATION IN EXPOSOME-INDUCED TUMORIGENESIS: EMERGING ROLES OF NCRNAS. ENVIRONMENTAL FACTORS, INCLUDING POLLUTANTS AND LIFESTYLE, CONSTITUTE A SIGNIFICANT ROLE IN SEVERE, CHRONIC PATHOLOGIES WITH AN ESSENTIAL SOCIETAL, ECONOMIC BURDEN. THE MEASUREMENT OF ALL ENVIRONMENTAL EXPOSURES AND ASSESSING THEIR CORRELATION WITH EFFECTS ON INDIVIDUAL HEALTH IS DEFINED AS THE EXPOSOME, WHICH INTERACTS WITH OUR UNIQUE CHARACTERISTICS SUCH AS GENETICS, PHYSIOLOGY, AND EPIGENETICS. EPIGENETICS INVESTIGATES MODIFICATIONS IN THE EXPRESSION OF GENES THAT DO NOT DEPEND ON THE UNDERLYING DNA SEQUENCE. SOME STUDIES HAVE CONFIRMED THAT ENVIRONMENTAL FACTORS MAY PROMOTE DISEASE IN INDIVIDUALS OR SUBSEQUENT PROGENY THROUGH EPIGENETIC ALTERATIONS. VARIATIONS IN THE EPIGENETIC MACHINERY CAUSE A SPECTRUM OF DIFFERENT DISORDERS SINCE THESE MECHANISMS ARE MORE SENSITIVE TO THE ENVIRONMENT THAN THE GENOME, DUE TO THE INHERENT REVERSIBLE NATURE OF THE EPIGENETIC LANDSCAPE. SEVERAL EPIGENETIC MECHANISMS, INCLUDING MODIFICATIONS IN DNA (E.G., METHYLATION), HISTONES, AND NONCODING RNAS CAN CHANGE GENOME EXPRESSION UNDER THE EXOGENOUS INFLUENCE. NOTABLY, THE ROLE OF LONG NONCODING RNAS IN EPIGENETIC PROCESSES HAS NOT BEEN WELL EXPLORED IN THE CONTEXT OF EXPOSOME-INDUCED TUMORIGENESIS. IN THE PRESENT REVIEW, OUR SCOPE IS TO PROVIDE RELEVANT EVIDENCE INDICATING THAT EPIGENETIC ALTERATIONS MEDIATE THOSE DETRIMENTAL EFFECTS CAUSED BY EXPOSURE TO ENVIRONMENTAL TOXICANTS, FOCUSING MAINLY ON A MULTI-STEP REGULATION BY DIVERSE NONCODING RNAS SUBTYPES. 2022