1 4810 75 OBESITY--A CHRONIC HEALTH PROBLEM IN CLONED MICE? THE MAJORITY OF CLONED ANIMALS DERIVED BY NUCLEAR TRANSFER DIE DURING GESTATION AND DISPLAY NEONATAL ABNORMALITIES. HOWEVER, BECAUSE OF THE LONG GENERATION INTERVAL OF CLONED ANIMAL SPECIES, THE LONG-TERM CONSEQUENCES OF CLONING ON HEALTH HAVE BEEN DIFFICULT TO ACCESS. RECENT STUDIES IN MICE HAVE PROVIDED EVIDENCE THAT CLONED ANIMALS MIGHT HAVE CHRONIC HEALTH PROBLEMS SUCH AS OBESITY. OBESITY IN CLONED MICE IS LIKELY TO REFLECT EPIGENETIC ABNORMALITIES THAT ARISE PARTLY FROM INADEQUATE NUCLEAR PROGRAMMING; THESE OBESE MICE DISPLAY A UNIQUE PHENOTYPE THAT IS SUGGESTIVE OF A DEFECT OTHER THAN MALFUNCTION OF THE LEPTIN-MELANOCORTIN SYSTEM, WHICH OCCURS IN MOST RODENT MODELS OF OBESITY AND IN HUMAN OBESITY. 2003 2 4496 25 MORE THAN GENES: THE ADVANCED FETAL PROGRAMMING HYPOTHESIS. MANY LINES OF DATA, INITIAL EPIDEMIOLOGIC STUDIES AS WELL AS SUBSEQUENT EXTENSIVE EXPERIMENTAL STUDIES, INDICATE THAT EARLY-LIFE EVENTS PLAY A POWERFUL ROLE IN INFLUENCING LATER SUCEPTIBILITY TO CERTAIN CHRONIC DISEASES. SUCH EVENTS MIGHT BE OVER- OR UNDERNUTRITION, EXPOSURE TO ENVIRONMENTAL TOXINS, BUT ALSO CHANGES IN HORMONES, IN PARTICULAR STRESS HORMONES. TYPICALLY, THOSE EVENTS ARE TRIGGERED BY THE ENVIRONMENTAL CHALLENGES OF THE MOTHER. HOWEVER, RECENT STUDIES HAVE SHOWN THAT PATERNAL ENVIRONMENTAL OR NUTRITIONAL FACTORS AFFECT THE PHENOTYPE OF THE OFFSPRING AS WELL. THE MATERNAL AND PATERNAL ENVIRONMENTAL FACTORS ACT ON THE PHENOTYPE OF THE OFFSPRING VIA EPIGENETIC MODIFICATION OF ITS GENOME. THE ADVANCED FETAL PROGRAMMING HYPOTHESIS PROPOSES AN ADDITIONAL NON-ENVIRONMENTALLY DRIVEN MECHANISM: MATERNAL AND ALSO PATERNAL GENES MAY INFLUENCE THE MATURATING SPERM, THE OOCYTE, AND LATER THE EMBRYO/FETUS, LEADING TO THEIR EPIGENETIC ALTERATION. THUS, THE OBSERVED PHENOTYPE OF THE OFFSPRING MAY BE ALTERED BY MATERNAL/PATERNAL GENES INDEPENDENT OF THE FETAL GENOME. MEANWHILE, SEVERAL INDEPENDENT ASSOCIATION STUDIES IN HUMANS DEALING WITH METABOLIC AND NEUROLOGICAL TRAITS ALSO SUGGEST THAT MATERNAL GENES MIGHT AFFECT THE OFFSPRING PHENOTYPE INDEPENDENT OF THE TRANSMISSION OF THAT PARTICULAR GENE TO THE OFFSPRING. CONSIDERING THE IMPLICATIONS OF THIS HYPOTHESIS, SOME CONCLUSIONS DRAWN FROM TRANSGENIC OR KNOCKOUT ANIMAL MODELS AND BASED ON THE CAUSALITY BETWEEN A GENETIC ALTERATION AND A PHENOTYPE, NEED TO BE CHALLENGED. POSSIBLE IMPLICATIONS FOR THE DEVELOPMENT, DIAGNOSTIC AND THERAPY OF HUMAN GENETIC DISEASES HAVE TO BE INVESTIGATED. 2014 3 1520 25 DNA METHYLATION AT DIFFERENTIALLY METHYLATED REGIONS OF IMPRINTED GENES IS RESISTANT TO DEVELOPMENTAL PROGRAMMING BY MATERNAL NUTRITION. THE NUTRITIONAL ENVIRONMENT IN WHICH THE MAMMALIAN FETUS OR INFANT DEVELOP IS RECOGNIZED AS INFLUENCING THE RISK OF CHRONIC DISEASES, SUCH AS TYPE 2 DIABETES AND HYPERTENSION, IN A PHENOMENON THAT HAS BECOME KNOWN AS DEVELOPMENTAL PROGRAMMING. THE LATE ONSET OF SUCH DISEASES IN RESPONSE TO EARLIER TRANSIENT EXPERIENCES HAS LED TO THE SUGGESTION THAT DEVELOPMENTAL PROGRAMMING MAY HAVE AN EPIGENETIC COMPONENT, BECAUSE EPIGENETIC MARKS SUCH AS DNA METHYLATION OR HISTONE TAIL MODIFICATIONS COULD PROVIDE A PERSISTENT MEMORY OF EARLIER NUTRITIONAL STATES. ONE CLASS OF GENES THAT HAS BEEN CONSIDERED A POTENTIAL TARGET OR MEDIATOR OF PROGRAMMING EVENTS IS IMPRINTED GENES, BECAUSE THESE GENES CRITICALLY DEPEND UPON EPIGENETIC MODIFICATIONS FOR CORRECT EXPRESSION AND BECAUSE MANY IMPRINTED GENES HAVE ROLES IN CONTROLLING FETAL GROWTH AS WELL AS NEONATAL AND ADULT METABOLISM. IN THIS STUDY, WE HAVE USED AN ESTABLISHED MODEL OF DEVELOPMENTAL PROGRAMMING-ISOCALORIC PROTEIN RESTRICTION TO FEMALE MICE DURING GESTATION OR LACTATION-TO EXAMINE WHETHER THERE ARE EFFECTS ON EXPRESSION AND DNA METHYLATION OF IMPRINTED GENES IN THE OFFSPRING. WE FIND THAT ALTHOUGH EXPRESSION OF SOME IMPRINTED GENES IN LIVER OF OFFSPRING IS ROBUSTLY AND SUSTAINABLY CHANGED, METHYLATION OF THE DIFFERENTIALLY METHYLATED REGIONS (DMRS) THAT CONTROL THEIR MONOALLELIC EXPRESSION REMAINS LARGELY UNALTERED. WE CONCLUDE THAT DEREGULATION OF IMPRINTING THROUGH A GENERAL EFFECT ON DMR METHYLATION IS UNLIKELY TO BE A COMMON FACTOR IN DEVELOPMENTAL PROGRAMMING. 2012 4 3848 18 IS EPIGENETICS AN IMPORTANT LINK BETWEEN EARLY LIFE EVENTS AND ADULT DISEASE? BACKGROUND: EPIGENETIC MECHANISMS PROVIDE ONE POTENTIAL EXPLANATION FOR HOW ENVIRONMENTAL INFLUENCES IN EARLY LIFE CAUSE LONG-TERM CHANGES IN CHRONIC DISEASE SUSCEPTIBILITY. WHEREAS EPIGENETIC DYSREGULATION IS INCREASINGLY IMPLICATED IN VARIOUS RARE DEVELOPMENTAL SYNDROMES AND CANCER, THE ROLE OF EPIGENETICS IN COMPLEX CHRONIC DISEASES, SUCH AS CARDIOVASCULAR DISEASE, TYPE 2 DIABETES AND OBESITY, REMAINS LARGELY UNCHARACTERIZED. EXTENSIVE WORK IN ANIMAL MODELS IS REQUIRED TO DEVELOP SPECIFIC HYPOTHESES THAT CAN BE PRACTICABLY TESTED IN HUMANS. ANIMAL MODELS: WE HAVE DEVELOPED A MOUSE MODEL SHOWING THAT METHYL DONOR SUPPLEMENTATION PREVENTS TRANSGENERATIONAL AMPLIFICATION OF OBESITY, SUGGESTING A ROLE FOR DNA METHYLATION IN THE DEVELOPMENTAL ESTABLISHMENT OF BODY WEIGHT REGULATION. CONCLUSIONS: COUPLING SUCH MODELS WITH RECENTLY DEVELOPED EPIGENOMIC TECHNOLOGIES SHOULD ULTIMATELY ENABLE US TO DETERMINE IF EPIGENETICS IS AN IMPORTANT LINK BETWEEN EARLY LIFE EVENTS AND ADULT DISEASE. 2009 5 4802 20 OBESITY AND LIFESPAN HEALTH--IMPORTANCE OF THE FETAL ENVIRONMENT. A MARKED INCREASE IN THE FREQUENCY OF OBESITY AT THE POPULATION LEVEL HAS RESULTED IN AN INCREASING NUMBER OF OBESE WOMEN ENTERING PREGNANCY. THE INCREASING REALIZATION OF THE IMPORTANCE OF THE FETAL ENVIRONMENT IN RELATION TO CHRONIC DISEASE ACROSS THE LIFESPAN HAS FOCUSED ATTENTION ON THE ROLE OF MATERNAL OBESITY IN FETAL DEVELOPMENT. PREVIOUS STUDIES HAVE DEMONSTRATED THAT OBESITY DURING ADOLESCENCE AND ADULTHOOD CAN BE TRACED BACK TO FETAL AND EARLY CHILDHOOD EXPOSURES. THIS REVIEW FOCUSES ON FACTORS THAT CONTRIBUTE TO EARLY DEVELOPMENTAL EVENTS, SUCH AS EPIGENETIC MODIFICATIONS, THE POTENTIAL FOR AN INCREASE IN INFLAMMATORY BURDEN, EARLY DEVELOPMENTAL PROGRAMMING CHANGES SUCH AS THE VARIABLE DEVELOPMENT OF WHITE VERSUS BROWN ADIPOSE TISSUE, AND ALTERATIONS IN ORGAN ONTOGENY. WE HYPOTHESIZE THAT THESE MECHANISMS PROMOTE AN UNFAVORABLE FETAL ENVIRONMENT AND CAN HAVE A LONG-STANDING IMPACT, WITH EARLY MANIFESTATIONS OF CHRONIC DISEASE THAT CAN RESULT IN AN INCREASED DEMAND FOR FUTURE HEALTH CARE. IN ORDER TO IDENTIFY APPROPRIATE PREVENTIVE MEASURES, ATTENTION NEEDS TO BE PLACED BOTH ON REDUCING MATERNAL OBESITY AS WELL AS UNDERSTANDING THE MOLECULAR, CELLULAR, AND EPIGENETIC MECHANISMS THAT MAY BE RESPONSIBLE FOR THE PRENATAL ONSET OF CHRONIC DISEASE. 2014 6 6133 26 THE EPIGENETIC ROLE OF VITAMIN C IN NEURODEVELOPMENT. THE MATERNAL DIET DURING PREGNANCY IS A KEY DETERMINANT OF OFFSPRING HEALTH. EARLY STUDIES HAVE LINKED POOR MATERNAL NUTRITION DURING GESTATION WITH A PROPENSITY FOR THE DEVELOPMENT OF CHRONIC CONDITIONS IN OFFSPRING. THESE CONDITIONS INCLUDE CARDIOVASCULAR DISEASE, TYPE 2 DIABETES AND EVEN COMPROMISED MENTAL HEALTH. WHILE MULTIPLE FACTORS MAY CONTRIBUTE TO THESE OUTCOMES, DISTURBED EPIGENETIC PROGRAMMING DURING EARLY DEVELOPMENT IS ONE POTENTIAL BIOLOGICAL MECHANISM. THE EPIGENOME IS PROGRAMMED PRIMARILY IN UTERO, AND DURING THIS TIME, THE DEVELOPING FETUS IS HIGHLY SUSCEPTIBLE TO ENVIRONMENTAL FACTORS SUCH AS NUTRITIONAL INSULTS. DURING NEURODEVELOPMENT, EPIGENETIC PROGRAMMING COORDINATES THE FORMATION OF PRIMITIVE CENTRAL NERVOUS SYSTEM STRUCTURES, NEUROGENESIS, AND NEUROPLASTICITY. DYSREGULATED EPIGENETIC PROGRAMMING HAS BEEN IMPLICATED IN THE AETIOLOGY OF SEVERAL NEURODEVELOPMENTAL DISORDERS SUCH AS TATTON-BROWN-RAHMAN SYNDROME. ACCORDINGLY, THERE IS GREAT INTEREST IN DETERMINING HOW MATERNAL NUTRIENT AVAILABILITY IN PREGNANCY MIGHT AFFECT THE EPIGENETIC STATUS OF OFFSPRING, AND HOW SUCH INFLUENCES MAY PRESENT PHENOTYPICALLY. IN RECENT YEARS, A NUMBER OF EPIGENETIC ENZYMES THAT ARE ACTIVE DURING EMBRYONIC DEVELOPMENT HAVE BEEN FOUND TO REQUIRE VITAMIN C AS A COFACTOR. THESE ENZYMES INCLUDE THE TEN-ELEVEN TRANSLOCATION METHYLCYTOSINE DIOXYGENASES (TETS) AND THE JUMONJI C DOMAIN-CONTAINING HISTONE LYSINE DEMETHYLASES THAT CATALYSE THE OXIDATIVE REMOVAL OF METHYL GROUPS ON CYTOSINES AND HISTONE LYSINE RESIDUES, RESPECTIVELY. THESE ENZYMES ARE INTEGRAL TO EPIGENETIC REGULATION AND HAVE FUNDAMENTAL ROLES IN CELLULAR DIFFERENTIATION, THE MAINTENANCE OF PLURIPOTENCY AND DEVELOPMENT. THE DEPENDENCE OF THESE ENZYMES ON VITAMIN C FOR OPTIMAL CATALYTIC ACTIVITY ILLUSTRATES A POTENTIALLY CRITICAL CONTRIBUTION OF THE NUTRIENT DURING MAMMALIAN DEVELOPMENT. THESE INSIGHTS ALSO HIGHLIGHT A POTENTIAL RISK ASSOCIATED WITH VITAMIN C INSUFFICIENCY DURING PREGNANCY. THE LINK BETWEEN VITAMIN C INSUFFICIENCY AND DEVELOPMENT IS PARTICULARLY APPARENT IN THE CONTEXT OF NEURODEVELOPMENT AND HIGH VITAMIN C CONCENTRATIONS IN THE BRAIN ARE INDICATIVE OF IMPORTANT FUNCTIONAL REQUIREMENTS IN THIS ORGAN. ACCORDINGLY, THIS REVIEW CONSIDERS THE EVIDENCE FOR THE POTENTIAL IMPACT OF MATERNAL VITAMIN C STATUS ON NEURODEVELOPMENTAL EPIGENETICS. 2022 7 6426 21 THE TRANSGENERATIONAL TRANSMISSION OF THE PATERNAL TYPE 2 DIABETES-INDUCED SUBFERTILITY PHENOTYPE. DIABETES IS A CHRONIC METABOLIC DISORDER CHARACTERIZED BY HYPERGLYCEMIA AND ASSOCIATED WITH MANY HEALTH COMPLICATIONS DUE TO THE LONG-TERM DAMAGE AND DYSFUNCTION OF VARIOUS ORGANS. A CONSEQUENTIAL COMPLICATION OF DIABETES IN MEN IS REPRODUCTIVE DYSFUNCTION, REDUCED FERTILITY, AND POOR REPRODUCTIVE OUTCOMES. HOWEVER, THE MOLECULAR MECHANISMS RESPONSIBLE FOR DIABETIC ENVIRONMENT-INDUCED SPERM DAMAGE AND OVERALL DECREASED REPRODUCTIVE OUTCOMES ARE NOT FULLY ESTABLISHED. WE EVALUATED THE EFFECTS OF TYPE 2 DIABETES EXPOSURE ON THE REPRODUCTIVE SYSTEM AND THE REPRODUCTIVE OUTCOMES OF MALES AND THEIR MALE OFFSPRING, USING A MOUSE MODEL. WE DEMONSTRATE THAT PATERNAL EXPOSURE TO TYPE 2 DIABETES MEDIATES INTERGENERATIONAL AND TRANSGENERATIONAL EFFECTS ON THE REPRODUCTIVE HEALTH OF THE OFFSPRING, ESPECIALLY ON SPERM QUALITY, AND ON METABOLIC CHARACTERISTICS. GIVEN THE TRANSGENERATIONAL IMPAIRMENT OF REPRODUCTIVE AND METABOLIC PARAMETERS THROUGH TWO GENERATIONS, THESE CHANGES LIKELY TAKE THE FORM OF INHERITED EPIGENETIC MARKS THROUGH THE GERMLINE. OUR RESULTS EMPHASIZE THE IMPORTANCE OF IMPROVING METABOLIC HEALTH NOT ONLY IN WOMEN OF REPRODUCTIVE AGE, BUT ALSO IN POTENTIAL FATHERS, IN ORDER TO REDUCE THE NEGATIVE IMPACTS OF DIABETES ON SUBSEQUENT GENERATIONS. 2021 8 1371 25 DEVELOPMENTAL ORIGINS OF HEALTH AND DISEASE: NEW INSIGHTS. EPIDEMIOLOGICAL AND ANIMAL STUDIES SHOW THAT SMALL CHANGES IN THE DEVELOPMENTAL ENVIRONMENT CAN INDUCE PHENOTYPIC CHANGES AFFECTING AN INDIVIDUAL'S RESPONSES TO THEIR LATER ENVIRONMENT. THESE MAY ALTER THE RISK OF CHRONIC DISEASE SUCH AS METABOLIC SYNDROME OR CARDIOVASCULAR DISEASE. RECENT RESEARCH SHOWS THAT ANIMALS EXPOSED TO SUCH A MISMATCH BETWEEN PRENATAL AND POSTNATAL ENVIRONMENT DEVELOP OBESITY, REDUCED ACTIVITY, LEPTIN AND INSULIN RESISTANCE, ELEVATED BLOOD PRESSURE AND VASCULAR ENDOTHELIAL DYSFUNCTION. EPIGENETIC PROCESSES ARE INVOLVED IN SUCH EFFECTS, TARGETED TO PROMOTER REGIONS OF SPECIFIC GENES IN SPECIFIC TISSUES. SUCH FINE CONTROL OF GENE EXPRESSION SUGGESTS THAT THE MECHANISMS HAVE BEEN RETAINED THROUGH EVOLUTION THROUGH THEIR ADAPTIVE ADVANTAGE, RATHER THAN REPRESENTING EXTREME EFFECTS OF DEVELOPMENTAL DISRUPTION AKIN TO TERATOGENESIS. THERE MAY BE ADAPTIVE ADVANTAGE IN A DEVELOPMENTAL CUE INDUCING A PHENOTYPIC CHANGE IN GENERATIONS BEYOND THE IMMEDIATE PREGNANCY, AND A RANGE OF DATA THAT SUPPORT THIS CONCEPT. IN ANIMALS, EPIGENETIC EFFECTS SUCH AS DNA METHYLATION CAN BE PASSED TO SUCCESSIVE GENERATIONS. ENVIRONMENTAL TOXINS, INCLUDING ENDOCRINE DISRUPTORS, MAY INDUCE GREATER RISK OF CHRONIC DISEASE, EVEN AT LOW EXPOSURE LEVELS, IF THEY AFFECT SUCH NORMAL DEVELOPMENTAL EPIGENETIC PROCESSES. APPROPRIATE INTERVENTIONS MAY HAVE LONG-TERM MULTIGENERATIONAL EFFECTS TO REDUCE THE RISK OF CHRONIC DISEASE. 2008 9 2137 25 EPIGENETIC INHERITANCE AND EVOLUTION: A PATERNAL PERSPECTIVE ON DIETARY INFLUENCES. THE EARLIEST INDICATIONS FOR PATERNALLY INDUCED TRANSGENERATIONAL EFFECTS FROM THE ENVIRONMENT TO FUTURE GENERATIONS WERE BASED ON A SMALL NUMBER OF LONG-TERM EPIDEMIOLOGICAL STUDIES AND SOME EMPIRICAL OBSERVATIONS. ONLY RECENTLY HAVE EXPERIMENTAL ANIMAL MODELS AND A FEW ANALYSES ON HUMAN DATA EXPLORED THE TRANSGENERATIONAL NATURE OF PHENOTYPIC CHANGES OBSERVED IN OFFSPRING. CHANGES INCLUDE MULTIPLE METABOLIC DISORDERS, CANCER AND OTHER CHRONIC DISEASES. THESE PHENOTYPES CANNOT ALWAYS BE EXPLAINED BY MENDELIAN INHERITANCE, DNA MUTATIONS OR GENETIC DAMAGE. HENCE, A NEW COMPELLING THEORY ON EPIGENETIC INHERITANCE IS GAINING INTEREST, PROVIDING NEW CONCEPTS THAT EXTEND DARWIN'S EVOLUTIONARY THEORY. EPIGENETIC ALTERATIONS OR "EPIMUTATIONS" ARE BEING CONSIDERED TO EXPLAIN TRANSGENERATIONAL INHERITANCE OF PARENTALLY ACQUIRED TRAITS. THE RESPONSIBLE MECHANISMS FOR THESE EPIMUTATIONS INCLUDE DNA METHYLATION, HISTONE MODIFICATION, AND RNA-MEDIATED EFFECTS. THIS REVIEW EXPLORES THE LITERATURE ON A NUMBER OF TIME-DEPENDENT ENVIRONMENTALLY INDUCED EPIGENETIC ALTERATIONS, SPECIFICALLY THOSE FROM DIETARY EXPOSURES. WE SUGGEST A ROLE FOR THE MALE GERM LINE AS ONE OF NATURE'S TOOLS TO CAPTURE MESSAGES FROM OUR CONTINUOUSLY CHANGING ENVIRONMENT AND TO TRANSFER THIS INFORMATION TO SUBSEQUENT GENERATIONS. FURTHER, WE OPEN THE DISCUSSION THAT THE PATERNALLY INHERITED EPIGENETIC INFORMATION MAY CONTRIBUTE TO EVOLUTIONARY ADAPTATION. 2015 10 3210 24 HEALTH EFFECTS ASSOCIATED WITH PRE- AND PERINATAL EXPOSURE TO ARSENIC. INORGANIC ARSENIC IS A WELL-ESTABLISHED HUMAN CARCINOGEN, ABLE TO INDUCE GENETIC AND EPIGENETIC ALTERATIONS. MORE THAN 200 MILLION PEOPLE WORLDWIDE ARE EXPOSED TO ARSENIC CONCENTRATIONS IN DRINKING WATER EXCEEDING THE RECOMMENDED WHO THRESHOLD (10MUG/L). ADDITIONALLY, CHRONIC EXPOSURE TO LEVELS BELOW THIS THRESHOLD IS KNOWN TO RESULT IN LONG-TERM HEALTH EFFECTS IN HUMANS. THE ARSENIC-RELATED HEALTH EFFECTS IN HUMANS ARE ASSOCIATED WITH ITS BIOTRANSFORMATION PROCESS, WHEREBY THE RESULTING METABOLITES CAN INDUCE MOLECULAR DAMAGE THAT ACCUMULATES OVER TIME. THE EFFECTS DERIVED FROM THESE ALTERATIONS INCLUDE GENOMIC INSTABILITY ASSOCIATED WITH OXIDATIVE DAMAGE, ALTERATION OF GENE EXPRESSION (INCLUDING CODING AND NON-CODING RNAS), GLOBAL AND LOCALIZED EPIGENETIC REPROGRAMMING, AND HISTONE POSTTRANSLATIONAL MODIFICATIONS. THESE ALTERATIONS DIRECTLY AFFECT MOLECULAR PATHWAYS INVOLVED IN THE ONSET AND PROGRESSION OF MANY CONDITIONS THAT CAN ARISE EVEN DECADES AFTER THE EXPOSURE OCCURS. IMPORTANTLY, ARSENIC METABOLITES GENERATED DURING ITS BIOTRANSFORMATION CAN ALSO PASS THROUGH THE PLACENTAL BARRIER, RESULTING IN FETAL EXPOSURE TO THIS CARCINOGEN AT SIMILAR LEVELS TO THOSE OF THE MOTHER. AS SUCH, MORE IMMEDIATE EFFECTS OF THE ARSENIC-INDUCED MOLECULAR DAMAGE CAN BE OBSERVED AS DETRIMENTAL EFFECTS ON FETAL DEVELOPMENT, PREGNANCY, AND BIRTH OUTCOMES. IN THIS REVIEW, WE FOCUS ON THE GENETIC AND EPIGENETIC DAMAGE ASSOCIATED WITH EXPOSURE TO LOW LEVELS OF ARSENIC, PARTICULARLY THOSE AFFECTING EARLY DEVELOPMENTAL STAGES. WE ALSO PRESENT HOW THESE ALTERATIONS OCCURRING DURING EARLY LIFE CAN IMPACT THE DEVELOPMENT OF CERTAIN DISEASES IN ADULT LIFE. 2021 11 4125 20 MECHANISMS OF DISEASE: IN UTERO PROGRAMMING IN THE PATHOGENESIS OF HYPERTENSION. NUTRITIONAL AND OTHER ENVIRONMENTAL CUES DURING DEVELOPMENT CAN PERMANENTLY ALTER THE STRUCTURE, HOMEOSTATIC SYSTEMS, AND FUNCTIONS OF THE BODY. THIS PHENOMENON HAS BEEN REFERRED TO AS 'PROGRAMMING'. EPIDEMIOLOGICAL AND ANIMAL STUDIES SHOW THAT PROGRAMMED EFFECTS OPERATE WITHIN THE NORMAL RANGE OF GROWTH AND DEVELOPMENT, AND INFLUENCE THE RISK OF CHRONIC DISEASE IN ADULT LIFE. WE REVIEW THE EVIDENCE THAT THESE EFFECTS INCLUDE REDUCED NEPHRON NUMBER AND COMPENSATORY ADAPTATIONS, WHICH MIGHT LEAD TO HYPERTENSION, AND PERHAPS ACCELERATE THE DECLINE IN RENAL FUNCTION THAT ACCOMPANIES AGING. THESE PROCESSES MIGHT BE EXACERBATED BY PROGRAMMED CHANGES IN VASCULAR STRUCTURE AND FUNCTION, AND ALTERATIONS IN ENDOCRINE AND METABOLIC HOMEOSTASIS. PROGRAMMED EFFECTS MIGHT BE INITIATED AS EARLY AS THE PERICONCEPTUAL PHASE OF DEVELOPMENT, AND COULD INVOLVE EPIGENETIC CHANGES IN GENE EXPRESSION OR ALTERED STEM CELL ALLOCATION. BETTER UNDERSTANDING OF THESE PROCESSES COULD LEAD TO THE DEVELOPMENT OF NOVEL DIAGNOSTIC AND PREVENTIVE MEASURES, AND TO EARLY DETECTION OF AT-RISK INDIVIDUALS. BY MONITORING BLOOD PRESSURE, WEIGHT, AND RENAL FUNCTION IN CHILDREN, IT MIGHT BE POSSIBLE TO REDUCE THE RISK OF CARDIOVASCULAR AND RENAL DISEASE IN LATER LIFE. 2006 12 2007 18 EPIGENETIC BASIS FOR FETAL ORIGINS OF AGE-RELATED DISEASE. THE CURRENT CONCEPT OF FETAL ORIGINS OF ADULT DISEASES DESCRIBES IN UTERO PROGRAMMING, OR ADAPTATION TO A SPECTRUM OF ADVERSE ENVIRONMENTAL CONDITIONS THAT ULTIMATELY LEADS TO INCREASED SUSCEPTIBILITY TO AGE-RELATED DISEASES (E.G., TYPE 2 DIABETES AND CARDIOVASCULAR DISEASE) LATER IN LIFE. ALTHOUGH THE PRECISE MECHANISM OF THIS BIOLOGICAL MEMORY REMAINS UNCLEAR, MOUNTING EVIDENCE SUGGESTS AN EPIGENETIC BASIS. THE INCREASED SUSCEPTIBILITY TO CHRONIC DISEASE AND INVOLVEMENT OF MULTIPLE ORGAN SYSTEMS THAT IS OBSERVED IS ANALOGOUS TO THE DECLINE IN RESISTANCE TO DISEASE THAT IS TYPICAL OF NORMAL AGING. ALTHOUGH THE CUMULATIVE ENVIRONMENT OVER THE COURSE OF A LIFETIME CAN INDUCE INCREASING EPIGENETIC DYSREGULATION, WE PROPOSE THAT ADVERSE EVENTS THAT OCCUR DURING EARLY DEVELOPMENT CAN INDUCE SIGNIFICANT ADDITIONAL DYSREGULATION OF THE EPIGENOME. HERE, WE DESCRIBE THE CURRENT EVIDENCE FOR FETAL ORIGINS OF ADULT DISEASE AND THE ASSOCIATED ROLE OF EPIGENETIC DYSREGULATION. IN ADDITION, WE PRESENT A NEW PERSPECTIVE ON THE INDUCTION OF EPIGENETIC ALTERATIONS IN UTERO, WHICH SUBSEQUENTLY LEAD TO AN AGING PHENOTYPE MARKED BY INCREASED SUSCEPTIBILITY TO AGE-RELATED DISEASES. 2010 13 4972 23 PATHOPHYSIOLOGICAL BASIS FOR COMPROMISED HEALTH BEYOND GENERATIONS: ROLE OF MATERNAL HIGH-FAT DIET AND LOW-GRADE CHRONIC INFLAMMATION. EARLY EXPOSURE TO A FAT-ENRICHED DIET PROGRAMS THE DEVELOPMENTAL PROFILE AND THUS IS ASSOCIATED WITH DISEASE SUSCEPTIBILITY IN SUBSEQUENT GENERATIONS. CHRONIC LOW-GRADE INFLAMMATION, RESULTING FROM MATERNAL HIGH-FAT DIET, IS ACTIVATED IN THE FETAL ENVIRONMENT AND IN MANY ORGANS OF OFFSPRING, INCLUDING PLACENTA, ADIPOSE, LIVER, VASCULAR SYSTEM AND BRAIN. THE PREVALENCE OF AN INFLAMMATORY RESPONSE IS HIGHLY ASSOCIATED WITH OBESITY INCIDENCE, CARDIOVASCULAR DISEASES, NONALCOHOLIC FATTY LIVER DISEASE AND BRAIN DAMAGE. SUBSTANTIAL STUDIES USING HIGH-FAT MODEL HAVE CONSISTENTLY DEMONSTRATED THE INCIDENCE OF SUCH INFLAMMATORY REACTIONS; HOWEVER, THE POTENTIAL CONTRIBUTION OF ACTIVE INFLAMMATION TOWARD THE PHYSIOLOGICAL OUTCOMES AND DEVELOPMENTAL DISEASES IS NEITHER DISCUSSED IN DEPTH NOR SYSTEMICALLY INTEGRATED. THEREFORE, WE AIM TO SUMMARIZE THE CURRENT FINDINGS IN REGARDS TO HOW A MATERNAL HIGH-FAT DIET INFLUENCES THE INFLAMMATORY STATUS, AND PROBABLE PATHOGENIC EFFECTS ON THE OFFSPRING. MORE IMPORTANTLY, SINCE LIMITED RESEARCH HAS BEEN CONDUCTED TO REVEAL THE EPIGENETIC REGULATION OF THESE INFLAMMATORY MARKERS BY MATERNAL HIGH-FAT DIET, WE SINCERELY HOPE THAT OUR REVIEW WILL NOT ONLY OUTLINE THE PATHOPHYSIOLOGICAL RELEVANCE OF INFLAMMATION BUT ALSO IDENTIFY A FUTURE DIRECTION FOR MECHANISTIC INVESTIGATION AND CLINICAL APPLICATION. 2015 14 2507 23 EPIGENETICS AND OBESITY: THE DEVIL IS IN THE DETAILS. OBESITY IS A COMPLEX DISEASE WITH MULTIPLE WELL-DEFINED RISK FACTORS. NEVERTHELESS, SUSCEPTIBILITY TO OBESITY AND ITS SEQUELAE WITHIN OBESOGENIC ENVIRONMENTS VARIES GREATLY FROM ONE PERSON TO THE NEXT, SUGGESTING A ROLE FOR GENE X ENVIRONMENT INTERACTIONS IN THE ETIOLOGY OF THE DISORDER. EPIGENETIC REGULATION OF THE HUMAN GENOME PROVIDES A PUTATIVE MECHANISM BY WHICH SPECIFIC ENVIRONMENTAL EXPOSURES CONVEY RISK FOR OBESITY AND OTHER HUMAN DISEASES AND IS ONE POSSIBLE MECHANISM THAT UNDERLIES THE GENE X ENVIRONMENT/TREATMENT INTERACTIONS OBSERVED IN EPIDEMIOLOGICAL STUDIES AND CLINICAL TRIALS. A STUDY PUBLISHED IN BMC MEDICINE THIS MONTH BY WANG ET AL. REPORTS ON AN EXAMINATION OF DNA METHYLATION IN PERIPHERAL BLOOD LEUKOCYTES OF LEAN AND OBESE ADOLESCENTS, COMPARING METHYLATION PATTERNS BETWEEN THE TWO GROUPS. THE AUTHORS IDENTIFIED TWO GENES THAT WERE DIFFERENTIALLY METHYLATED, BOTH OF WHICH HAVE ROLES IN IMMUNE FUNCTION. HERE WE OVERVIEW THE FINDINGS FROM THIS STUDY IN THE CONTEXT OF THOSE EMERGING FROM OTHER RECENT GENETIC AND EPIGENETIC STUDIES, DISCUSS THE STRENGTHS AND WEAKNESSES OF THE STUDY AND SPECULATE ON THE FUTURE OF EPIGENETICS IN CHRONIC DISEASE RESEARCH. 2010 15 6844 22 [METABOLIC PROGRAMMING: THEORETICAL CONCEPTS AND EXPERIMENTAL EVIDENCE]. IT IS KNOWN THAT THE POOR NUTRITION DURING A FETAL DEVELOPMENT MAY CONTRIBUTE TO AN INCREASED RISK OF CHRONIC DISEASES IN ADULTHOOD. IN A MODERN LITERATURE, THIS PHENOMENON IS CALLED <>. IT IS ASSUMED THAT THE QUALITATIVE OR QUANTITATIVE DEFICIENCY OF CERTAIN NUTRITIONAL COMPONENTS DURING AN EARLY DEVELOPMENT MAY LEAD TO THE ADAPTATIONS THAT CONTRIBUTE TO IMPROVED SURVIVAL DURING THE PRENATAL AND EARLY POSTNATAL PERIODS OF AN ONTOGENESIS. HOWEVER, THE CONSEQUENCE OF SUCH ADAPTIVE CHANGES MAY ALSO BE THE DEVELOPMENT OF VARIOUS PATHOLOGICAL PROCESSES AT THE LATER STAGES OF LIFE. RECENT STUDIES HAVE SHOWN THAT ONE OF THE MAJOR MECHANISMS INVOLVED IN THESE ADAPTATIONS IS THE EPIGENETIC REGULATION OF A GENE ACTIVITY. IN THIS REVIEW, THE EXPERIMENTAL EVIDENCE IS PROVIDED THAT PROCESSES ARISING FROM A QUANTITATIVELY OR QUALITATIVELY RESTRICTED DIET DURING THE EARLY STAGES OF DEVELOPMENT PLAY AN IMPORTANT ROLE IN THE FURTHER LIFE AND CAN GREATLY INFLUENCE RISK OF VARIOUS AGE-RELATED DISEASES AND LIFE SPAN. 2013 16 2159 23 EPIGENETIC MECHANISMS IMPACTED BY CHRONIC STRESS ACROSS THE RODENT LIFESPAN. EXPOSURES TO STRESS AT ALL STAGES OF DEVELOPMENT CAN LEAD TO LONG-TERM BEHAVIOURAL EFFECTS, IN PART THROUGH CHANGES IN THE EPIGENOME. THIS REVIEW DESCRIBES RODENT RESEARCH SUGGESTING THAT STRESS IN PRENATAL, POSTNATAL, ADOLESCENT AND ADULT STAGES LEADS TO LONG-TERM CHANGES IN EPIGENETIC REGULATION IN THE BRAIN WHICH HAVE CAUSAL IMPACTS ON RODENT BEHAVIOUR. WE FOCUS ON STRESS-INDUCED EPIGENETIC CHANGES THAT HAVE BEEN LINKED TO BEHAVIOURAL DEFICITS INCLUDING POOR LEARNING AND MEMORY, AND INCREASED ANXIETY-LIKE AND DEPRESSIVE-LIKE BEHAVIOURS. INTERESTINGLY, ASPECTS OF THESE STRESS-INDUCED BEHAVIOURAL CHANGES CAN BE TRANSMITTED TO OFFSPRING ACROSS SEVERAL GENERATIONS, A PHENOMENON THAT HAS BEEN PROPOSED TO RESULT VIA EPIGENETIC MECHANISMS IN THE GERMLINE. HERE, WE ALSO DISCUSS EVIDENCE FOR THE DIFFERENTIAL IMPACT OF STRESS ON THE EPIGENOME IN MALES AND FEMALES, CONSCIOUS OF THE FACT THAT THE MAJORITY OF PUBLISHED STUDIES HAVE ONLY INVESTIGATED MALES. THIS HAS LED TO A LIMITED PICTURE OF THE EPIGENETIC IMPACT OF STRESS, HIGHLIGHTING THE NEED FOR FUTURE STUDIES TO INVESTIGATE FEMALES AS WELL AS MALES. 2022 17 2471 20 EPIGENETIC TRANSGENERATIONAL INHERITANCE OF ALTERED STRESS RESPONSES. ANCESTRAL ENVIRONMENTAL EXPOSURES HAVE PREVIOUSLY BEEN SHOWN TO PROMOTE EPIGENETIC TRANSGENERATIONAL INHERITANCE AND INFLUENCE ALL ASPECTS OF AN INDIVIDUAL'S LIFE HISTORY. IN ADDITION, PROXIMATE LIFE EVENTS SUCH AS CHRONIC STRESS HAVE DOCUMENTED EFFECTS ON THE DEVELOPMENT OF PHYSIOLOGICAL, NEURAL, AND BEHAVIORAL PHENOTYPES IN ADULTHOOD. WE USED A SYSTEMS BIOLOGY APPROACH TO INVESTIGATE IN MALE RATS THE INTERACTION OF THE ANCESTRAL MODIFICATIONS CARRIED TRANSGENERATIONALLY IN THE GERM LINE AND THE PROXIMATE MODIFICATIONS INVOLVING CHRONIC RESTRAINT STRESS DURING ADOLESCENCE. WE FIND THAT A SINGLE EXPOSURE TO A COMMON-USE FUNGICIDE (VINCLOZOLIN) THREE GENERATIONS REMOVED ALTERS THE PHYSIOLOGY, BEHAVIOR, METABOLIC ACTIVITY, AND TRANSCRIPTOME IN DISCRETE BRAIN NUCLEI IN DESCENDANT MALES, CAUSING THEM TO RESPOND DIFFERENTLY TO CHRONIC RESTRAINT STRESS. THIS ALTERATION OF BASELINE BRAIN DEVELOPMENT PROMOTES A CHANGE IN NEURAL GENOMIC ACTIVITY THAT CORRELATES WITH CHANGES IN PHYSIOLOGY AND BEHAVIOR, REVEALING THE INTERACTION OF GENETICS, ENVIRONMENT, AND EPIGENETIC TRANSGENERATIONAL INHERITANCE IN THE SHAPING OF THE ADULT PHENOTYPE. THIS IS AN IMPORTANT DEMONSTRATION IN AN ANIMAL THAT ANCESTRAL EXPOSURE TO AN ENVIRONMENTAL COMPOUND MODIFIES HOW DESCENDANTS OF THESE PROGENITOR INDIVIDUALS PERCEIVE AND RESPOND TO A STRESS CHALLENGE EXPERIENCED DURING THEIR OWN LIFE HISTORY. 2012 18 1801 25 EFFECT OF MATERNAL DIET ON THE EPIGENOME: IMPLICATIONS FOR HUMAN METABOLIC DISEASE. THE RAPID INCREASE IN THE INCIDENCE OF CHRONIC NON-COMMUNICABLE DISEASES OVER THE PAST TWO DECADES CANNOT BE EXPLAINED SOLELY BY GENETIC AND ADULT LIFESTYLE FACTORS. THERE IS NOW CONSIDERABLE EVIDENCE THAT THE FETAL AND EARLY POSTNATAL ENVIRONMENT ALSO STRONGLY INFLUENCES THE RISK OF DEVELOPING SUCH DISEASES IN LATER LIFE. HUMAN STUDIES HAVE SHOWN THAT LOW BIRTH WEIGHT IS ASSOCIATED WITH AN INCREASED RISK OF CVD, TYPE II DIABETES, OBESITY AND HYPERTENSION, ALTHOUGH RECENT STUDIES HAVE SHOWN THAT OVER-NUTRITION IN EARLY LIFE CAN ALSO INCREASE SUSCEPTIBILITY TO FUTURE METABOLIC DISEASE. THESE FINDINGS HAVE BEEN REPLICATED IN A VARIETY OF ANIMAL MODELS, WHICH HAVE SHOWN THAT BOTH MATERNAL UNDER- AND OVER-NUTRITION CAN INDUCE PERSISTENT CHANGES IN GENE EXPRESSION AND METABOLISM WITHIN THE OFFSPRING. THE MECHANISM BY WHICH THE MATERNAL NUTRITIONAL ENVIRONMENT INDUCES SUCH CHANGES IS BEGINNING TO BE UNDERSTOOD AND INVOLVES THE ALTERED EPIGENETIC REGULATION OF SPECIFIC GENES. THE DEMONSTRATION OF A ROLE FOR ALTERED EPIGENETIC REGULATION OF GENES IN THE DEVELOPMENTAL INDUCTION OF CHRONIC DISEASES RAISES THE POSSIBILITY THAT NUTRITIONAL OR PHARMACEUTICAL INTERVENTIONS MAY BE USED TO MODIFY LONG-TERM CARDIO-METABOLIC DISEASE RISK AND COMBAT THIS RAPID RISE IN CHRONIC NON-COMMUNICABLE DISEASES. 2011 19 5650 19 SEX DIFFERENCES IN THE DEVELOPMENT OF PHYSICAL AGGRESSION: AN INTERGENERATIONAL PERSPECTIVE AND IMPLICATIONS FOR PREVENTIVE INTERVENTIONS. THIS ARTICLE REVIEWS THE STATE OF KNOWLEDGE ON THE DEVELOPMENT OF CHRONIC PHYSICAL AGGRESSION (CPA), WITH THE AIM OF IDENTIFYING THE MOST EFFECTIVE PREVENTION STRATEGIES. WE SPECIFICALLY FOCUS ON THE EARLY DEVELOPMENT OF PHYSICAL AGGRESSION, ON SEX DIFFERENCES IN THE USE OF PHYSICAL AGGRESSION, AND ON THE TRANSMISSION OF BEHAVIOR PROBLEMS FROM ONE GENERATION TO THE OTHER. THE BODY OF RESEARCH ON THE DEVELOPMENT OF CPA FROM THE PAST THREE DECADES THAT WE REVIEW SHOWS INCREASING EVIDENCE THAT ITS PREVENTION REQUIRES A LONG-TERM BIOPSYCHOSOCIAL DEVELOPMENTAL APPROACH WHICH ALSO MUST INCLUDE AN INTERGENERATIONAL PERSPECTIVE. RECENT GENETIC AND EPIGENETIC RESEARCH HAS INDICATED THAT THERE ARE BOTH IMPORTANT GENETIC AND ENVIRONMENTAL EFFECTS ON GENE EXPRESSION WHICH START AT CONCEPTION. WE CONCLUDE THAT ONE OF THE MOST EFFECTIVE STRATEGIES TO BREAK THE INTERGENERATIONAL TRANSMISSION OF CPA INVOLVES GIVING LONG-TERM SUPPORT TO PREGNANT WOMEN WITH A HISTORY OF BEHAVIOR PROBLEMS, THEIR SPOUSE, AND THEIR OFFSPRING. 2019 20 6812 20 [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