1 1609 135 DNA METHYLATION-INDEPENDENT GROWTH RESTRICTION AND ALTERED DEVELOPMENTAL PROGRAMMING IN A MOUSE MODEL OF PRECONCEPTION MALE ALCOHOL EXPOSURE. THE PRECONCEPTION ENVIRONMENT IS A SIGNIFICANT MODIFIER OF DYSGENESIS AND THE DEVELOPMENT OF ENVIRONMENTALLY-INDUCED DISEASE. TO DATE, FETAL ALCOHOL SPECTRUM DISORDERS (FASDS) HAVE BEEN EXCLUSIVELY ASSOCIATED WITH MATERNAL EXPOSURES, YET EMERGING EVIDENCE SUGGESTS MALE-INHERITED ALTERATIONS IN THE DEVELOPMENTAL PROGRAM OF SPERM MAY BE RELEVANT TO THE GROWTH-RESTRICTION PHENOTYPES OF THIS CONDITION. USING A MOUSE MODEL OF VOLUNTARY CONSUMPTION, WE FIND CHRONIC PRECONCEPTION MALE ETHANOL EXPOSURE ASSOCIATES WITH FETAL GROWTH RESTRICTION, DECREASED PLACENTAL EFFICIENCY, ABNORMALITIES IN CHOLESTEROL TRAFFICKING, SEX-SPECIFIC ALTERATIONS IN THE GENETIC PATHWAYS REGULATING HEPATIC FIBROSIS, AND DISRUPTIONS IN THE REGULATION OF IMPRINTED GENES. ALTERATIONS IN THE DNA METHYLATION PROFILES OF IMPRINTED LOCI HAVE BEEN IDENTIFIED IN CLINICAL STUDIES OF ALCOHOLIC SPERM, SUGGESTING THE LEGACY OF PATERNAL DRINKING MAY TRANSMIT VIA HERITABLE DISRUPTIONS IN THE REGULATION OF IMPRINTED GENES. HOWEVER, THE CAPACITY OF SPERM-INHERITED CHANGES IN DNA METHYLATION TO BROADLY TRANSMIT ENVIRONMENTALLY-INDUCED PHENOTYPES REMAINS UNCONFIRMED. USING BISULPHITE MUTAGENESIS AND SECOND-GENERATION DEEP SEQUENCING, WE FIND NO EVIDENCE TO SUGGEST THAT THESE PHENOTYPES OR ANY OF THE ASSOCIATED TRANSCRIPTIONAL CHANGES ARE LINKED TO ALTERATIONS IN THE SPERM-INHERITED DNA METHYLATION PROFILE. THESE OBSERVATIONS ARE CONSISTENT WITH RECENT STUDIES EXAMINING THE MALE TRANSMISSION OF DIET-INDUCED PHENOTYPES AND EMPHASIZE THE IMPORTANCE OF EPIGENETIC MECHANISMS OF PATERNAL INHERITANCE BEYOND DNA METHYLATION. THIS STUDY CHALLENGES THE SINGULAR IMPORTANCE OF MATERNAL ALCOHOL EXPOSURES AND SUGGESTS PATERNAL ALCOHOL ABUSE IS A SIGNIFICANT, YET OVERLOOKED EPIDEMIOLOGICAL FACTOR COMPLICIT IN THE GENESIS OF ALCOHOL-INDUCED GROWTH DEFECTS, AND MAY PROVIDE MECHANISTIC INSIGHT INTO THE FAILURE OF FASD CHILDREN TO THRIVE POSTNATALLY. 2017 2 341 38 ALTERATIONS IN SPERM-INHERITED NONCODING RNAS ASSOCIATE WITH LATE-TERM FETAL GROWTH RESTRICTION INDUCED BY PRECONCEPTION PATERNAL ALCOHOL USE. USING A MOUSE MODEL, OUR GROUP RECENTLY DESCRIBED AN ASSOCIATION BETWEEN CHRONIC PATERNAL ALCOHOL USE PRIOR TO CONCEPTION AND DEFICITS IN OFFSPRING GROWTH. HERE, WE SOUGHT TO DETERMINE THE IMPACT OF ALCOHOL EXPOSURE ON MALE REPRODUCTIVE PHYSIOLOGY AND THE ASSOCIATION OF SPERM-INHERITED NONCODING RNAS WITH THE TRANSMISSION OF THE OBSERVED GROWTH DEFECTS. ALCOHOL EXPOSURE DID NOT APPRECIABLY ALTER MALE REPRODUCTIVE PHYSIOLOGY OR FERTILITY. HOWEVER, CHRONIC ALCOHOL USE REPRODUCIBLY INDUCED LATE-TERM FETAL GROWTH RESTRICTION IN THE OFFSPRING, WHICH CORRELATED WITH A SHIFT IN THE PROPORTIONAL RATIO OF TRANSFER RNA-DERIVED SMALL RNAS TO PIWI-INTERACTING RNAS, AS WELL AS ALTERED ENRICHMENT OF MICRORNAS MIR21, MIR30, AND MIR142 IN ALCOHOL-EXPOSED SPERM. ALTHOUGH OUR DATASET SHARE SIMILARITIES TO PRIOR WORKS EXAMINING THE IMPACT OF PATERNAL STRESS ON OFFSPRING PHENOTYPE, WE WERE UNABLE TO IDENTIFY ANY CHANGES IN PLASMA CORTICOSTERONE, INDICATING ALCOHOL MAY ALTER SPERM-INHERITED NONCODING RNAS THROUGH DISTINCT MECHANISMS. 2019 3 2471 29 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 4 1520 37 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 5 4496 41 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 6 2158 36 EPIGENETIC MECHANISMS FOR NUTRITION DETERMINANTS OF LATER HEALTH OUTCOMES. EPIGENETIC MARKING ON GENES CAN DETERMINE WHETHER OR NOT GENES ARE EXPRESSED. EPIGENETIC REGULATION IS MEDIATED BY THE ADDITION OF METHYL GROUPS TO DNA CYTOSINE BASES, OF METHYL AND ACETYL GROUPS TO PROTEINS (HISTONES) AROUND WHICH DNA IS WRAPPED, AND BY SMALL INTERFERING RNA MOLECULES. SOME COMPONENTS OF EPIGENETIC REGULATION HAVE EVOLVED TO PERMIT CONTROL OF WHETHER MATERNAL OR PATERNAL GENES ARE EXPRESSED. THE EPIGENETIC IMPRINTING OF IGF2 EXPRESSION IS AN EXAMPLE OF MATERNAL AND PATERNAL EPIGENETIC MARKING THAT MODULATES FETAL GROWTH AND FETAL SIZE. HOWEVER, EPIGENETIC REGULATION ALSO PERMITS THE FETUS AND THE INFANT TO ADAPT GENE EXPRESSION TO THE ENVIRONMENT IN WHICH IT IS GROWING; SOMETIMES WHEN THIS ADJUSTMENT GOES AWRY, THE RISK OF CHRONIC DISEASE IS INCREASED. RECENT PROGRESS IN THE UNDERSTANDING OF NUTRITIONAL INFLUENCES ON EPIGENETICS SUGGESTS THAT NUTRIENTS THAT ARE PART OF METHYL-GROUP METABOLISM CAN SIGNIFICANTLY INFLUENCE EPIGENETICS. DURING CRITICAL PERIODS IN DEVELOPMENT, DIETARY METHYL-GROUP INTAKE (CHOLINE, METHIONINE, AND FOLATE) CAN ALTER DNA AND HISTONE METHYLATION, WHICH RESULTS IN LIFELONG CHANGES IN GENE EXPRESSION. IN RODENT MODELS, PREGNANT DAMS THAT WERE FED DIETS HIGH IN METHIONINE, FOLIC ACID, AND CHOLINE PRODUCED OFFSPRING WITH DIFFERENT COAT COLORS OR WITH KINKED TAILS. A NUMBER OF SYNDROMES IN HUMANS CAN BE CAUSED BY DEFECTIVE EPIGENETIC REGULATION, INCLUDING RETT SYNDROME. THERE ARE INTERESTING EXAMPLES OF THE EFFECTS OF NUTRITION IN EARLY LIFE THAT RESULT IN ALTERED HEALTH IN ADULTS, AND SOME OF THESE COULD BE THE RESULT OF ALTERED EPIGENETIC REGULATION OF GENE EXPRESSION. 2009 7 3784 34 INTERGENERATIONAL EFFECTS OF ALCOHOL: A REVIEW OF PATERNAL PRECONCEPTION ETHANOL EXPOSURE STUDIES AND EPIGENETIC MECHANISMS IN THE MALE GERMLINE. WHILE ALCOHOL USE DISORDER (AUD) IS A HIGHLY HERITABLE PSYCHIATRIC DISEASE, EFFORTS TO ELUCIDATE THAT HERITABILITY BY EXAMINING GENETIC VARIATION (E.G., SINGLE NUCLEOTIDE POLYMORPHISMS) HAVE BEEN INSUFFICIENT TO FULLY ACCOUNT FOR FAMILIAL AUD RISK. PERHAPS NOT COINCIDENTLY, THERE HAS BEEN A BURGEONING INTEREST IN NOVEL NONGENOMIC MECHANISMS OF INHERITANCE (I.E., EPIGENETICS) THAT ARE SHAPED IN THE MALE OR FEMALE GERM CELLS BY SIGNIFICANT LIFETIME EXPERIENCES SUCH AS EXPOSURE TO CHRONIC STRESS, MALNUTRITION, OR DRUGS OF ABUSE. WHILE MANY EPIDEMIOLOGICAL AND PRECLINICAL STUDIES HAVE LONG POINTED TO A ROLE FOR THE PARENTAL PRECONCEPTION ENVIRONMENT IN OFFSPRING BEHAVIOR, OVER THE LAST DECADE MANY STUDIES HAVE IMPLICATED A CAUSAL RELATIONSHIP BETWEEN THE ENVIRONMENTALLY SENSITIVE SPERM EPIGENOME AND INTERGENERATIONAL PHENOTYPES. THIS CRITICAL REVIEW WILL DETAIL THE HERITABLE EFFECTS OF ALCOHOL AND THE POTENTIAL ROLE FOR EPIGENETICS. 2019 8 3215 46 HEAVY CHRONIC INTERMITTENT ETHANOL EXPOSURE ALTERS SMALL NONCODING RNAS IN MOUSE SPERM AND EPIDIDYMOSOMES. WHILE THE RISKS OF MATERNAL ALCOHOL ABUSE DURING PREGNANCY ARE WELL-ESTABLISHED, SEVERAL PRECLINICAL STUDIES SUGGEST THAT CHRONIC PRECONCEPTION ALCOHOL CONSUMPTION BY EITHER PARENT MAY ALSO HAVE SIGNIFICANCE CONSEQUENCES FOR OFFSPRING HEALTH AND DEVELOPMENT. NOTABLY, SINCE ISOGENIC MALE MICE USED IN THESE STUDIES ARE NOT INVOLVED IN GESTATION OR REARING OF OFFSPRING, THE CROSS-GENERATIONAL EFFECTS OF PATERNAL ALCOHOL EXPOSURE SUGGEST A GERMLINE-BASED EPIGENETIC MECHANISM. MANY RECENT STUDIES HAVE DEMONSTRATED THAT THE EFFECTS OF PATERNAL ENVIRONMENTAL EXPOSURES SUCH AS STRESS OR MALNUTRITION CAN BE TRANSMITTED TO THE NEXT GENERATION VIA ALTERATIONS TO SMALL NONCODING RNAS IN SPERM. THEREFORE, WE USED HIGH THROUGHPUT SEQUENCING TO EXAMINE THE EFFECT OF PRECONCEPTION ETHANOL ON SMALL NONCODING RNAS IN SPERM. WE FOUND THAT CHRONIC INTERMITTENT ETHANOL EXPOSURE ALTERED SEVERAL SMALL NONCODING RNAS FROM THREE OF THE MAJOR SMALL RNA CLASSES IN SPERM, TRNA-DERIVED SMALL RNA (TDR), MITOCHONDRIAL SMALL RNA, AND MICRORNA. SIX OF THE ETHANOL-RESPONSIVE SMALL NONCODING RNAS WERE EVALUATED WITH RT-QPCR ON A SEPARATE COHORT OF MICE AND FIVE OF THE SIX WERE CONFIRMED TO BE ALTERED BY CHRONIC ETHANOL EXPOSURE, SUPPORTING THE VALIDITY OF THE SEQUENCING RESULTS. IN ADDITION TO ALTERED SPERM RNA ABUNDANCE, CHRONIC ETHANOL EXPOSURE AFFECTED POST-TRANSCRIPTIONAL MODIFICATIONS TO SPERM SMALL NONCODING RNAS, INCREASING TWO NUCLEOSIDE MODIFICATIONS PREVIOUSLY IDENTIFIED IN MITOCHONDRIAL TRNA. FURTHERMORE, WE FOUND THAT CHRONIC ETHANOL REDUCED EPIDIDYMAL EXPRESSION OF A TRNA METHYLTRANSFERASE, NSUN2, KNOWN TO DIRECTLY REGULATE TDR BIOGENESIS. FINALLY, ETHANOL-RESPONSIVE SPERM TDR ARE SIMILARLY ALTERED IN EXTRACELLULAR VESICLES OF THE EPIDIDYMIS (I.E., EPIDIDYMOSOMES), SUPPORTING THE HYPOTHESIS THAT ALTERATIONS TO SPERM TDR EMERGE IN THE EPIDIDYMIS AND THAT EPIDIDYMOSOMES ARE THE PRIMARY SOURCE OF SMALL NONCODING RNAS IN SPERM. THESE RESULTS ADD CHRONIC ETHANOL TO THE GROWING LIST OF PATERNAL EXPOSURES THAT CAN AFFECT SMALL NONCODING RNA ABUNDANCE AND NUCLEOSIDE MODIFICATIONS IN SPERM. AS SMALL NONCODING RNAS IN SPERM HAVE BEEN SHOWN TO CAUSALLY INDUCE HERITABLE PHENOTYPES IN OFFSPRING, ADDITIONAL RESEARCH IS WARRANTED TO UNDERSTAND THE POTENTIAL EFFECTS OF ETHANOL-RESPONSIVE SPERM SMALL NONCODING RNAS ON OFFSPRING HEALTH AND DEVELOPMENT. 2018 9 3714 34 INHERITANCE OF SOCIAL DOMINANCE IS ASSOCIATED WITH GLOBAL SPERM DNA METHYLATION IN INBRED MALE MICE. DOMINANCE RELATIONSHIPS BETWEEN MALES AND THEIR ASSOCIATED TRAITS ARE USUALLY HERITABLE AND HAVE IMPLICATIONS FOR SEXUAL SELECTION IN ANIMALS. IN PARTICULAR, SOCIAL DOMINANCE AND ITS RELATED MALE PHEROMONES ARE HERITABLE IN INBRED MICE; THUS, WE WONDERED WHETHER EPIGENETIC CHANGES DUE TO ALTERED LEVELS OF DNA METHYLATION DETERMINE INHERITANCE. HERE, WE USED C57BL/6 MALE MICE TO ESTABLISH A SOCIAL DOMINANCE-SUBORDINATION RELATIONSHIP THROUGH CHRONIC DYADIC ENCOUNTERS, AND THIS RELATIONSHIP AND PHEROMONE COVARIATION OCCURRED IN THEIR OFFSPRING, INDICATIVE OF HERITABILITY. THROUGH TRANSCRIPTOME SEQUENCING AND WHOLE-GENOME DNA METHYLATION PROFILING OF THE SPERM OF BOTH GENERATIONS, WE FOUND THAT DIFFERENTIAL METHYLATION OF MANY GENES WAS INDUCED BY SOCIAL DOMINANCE-SUBORDINATION IN SIRES AND COULD BE PASSED ON TO THE OFFSPRING. THESE METHYLATED GENES WERE MAINLY RELATED TO GROWTH AND DEVELOPMENT PROCESSES, NEURODEVELOPMENT, AND CELLULAR TRANSPORTATION. THE EXPRESSION OF THE GENES WITH SIMILAR FUNCTIONS IN WHOLE-GENOME METHYLATION/BISULFITE SEQUENCING WAS ALSO DIFFERENTIATED BY SOCIAL DOMINANCE-SUBORDINATION, AS REVEALED BY RNA-SEQ. IN PARTICULAR, THE GENE DENND1A, WHICH REGULATES NEURAL SIGNALING, WAS DIFFERENTIALLY METHYLATED AND EXPRESSED IN THE SPERM AND MEDIAL PREFRONTAL CORTEX IN PAIRED MALES BEFORE AND AFTER DOMINANCE-SUBORDINATION ESTABLISHMENT, SUGGESTING THE POTENTIAL EPIGENETIC CONTROL AND INHERITANCE OF SOCIAL DOMINANCE-RELATED AGGRESSION. WE SUGGEST THAT SOCIAL DOMINANCE MIGHT BE PASSED ON TO MALE OFFSPRING THROUGH SPERM DNA METHYLATION AND THAT THE DIFFERENCES COULD POTENTIALLY AFFECT MALE COMPETITION IN OFFSPRING BY AFFECTING THE DEVELOPMENT OF THE NERVOUS SYSTEM. 2023 10 2235 28 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 11 3042 37 GENOME-WIDE ALTERATION OF HISTONE METHYLATION PROFILES ASSOCIATED WITH COGNITIVE CHANGES IN RESPONSE TO DEVELOPMENTAL ARSENIC EXPOSURE IN MICE. INORGANIC ARSENIC IS A XENOBIOTIC ENTERING THE BODY PRIMARILY THROUGH CONTAMINATED DRINKING WATER AND FOOD. THERE ARE DEFINED MECHANISMS THAT DESCRIBE ARSENIC'S ASSOCIATION WITH INCREASED CANCER INCIDENCE, HOWEVER MECHANISMS EXPLAINING ARSENIC EXPOSURE AND NEURODEVELOPMENTAL OR AGING DISORDERS ARE POORLY DEFINED. IN RECENT YEARS, ARSENIC EFFECTS ON EPIGENOME HAVE BECOME A PARTICULAR FOCUS. WE HYPOTHESIZE THAT HUMAN RELEVANT ARSENIC EXPOSURE DURING PARTICULAR DEVELOPMENTAL WINDOWS, OR LONG-TERM EXPOSURE LATER IN LIFE INDUCE PATHOPHYSIOLOGICAL NEURAL CHANGES THROUGH EPIGENOMIC ALTERATIONS, IN PARTICULAR HISTONE METHYLATION PROFILE, MANIFESTING AS COGNITIVE DECLINE. C57BL/6 WILD-TYPE MICE WERE CONTINUALLY EXPOSED TO SODIUM ARSENITE (100 MICROG/L) IN DRINKING WATER PRIOR TO MATING THROUGH WEANING OF THE EXPERIMENTAL PROGENY. A SECOND COHORT OF AGED APP/PS MICE WERE CHRONICALLY EXPOSED TO THE SAME LEVEL OF ARSENIC. COGNITIVE TESTING, HISTOLOGICAL EXAMINATION OF BRAINS AND GENOME-WIDE METHYLATION LEVELS OF H3K4ME3 AND H3K27ME3 EXAMINED AFTER CHIP-SEQ WERE USED TO DETERMINE THE EFFECTS OF ARSENIC EXPOSURE. DEVELOPMENTAL ARSENIC EXPOSURE CAUSED SIGNIFICANTLY DIMINISHED COGNITION IN WILD-TYPE MICE. THE ANALYSIS OF CHIP-SEQ DATA AND EXPERIMENTS WITH MOUSE EMBRYONIC STEM CELLS DEMONSTRATED THAT EPIGENETIC CHANGES INDUCED BY ARSENIC EXPOSURE TRANSLATED INTO GENE EXPRESSION ALTERATIONS ASSOCIATED WITH NEURONAL DEVELOPMENT AND NEUROLOGICAL DISEASE. INCREASED HIPPOCAMPAL AMYLOID PLAQUES LEVELS OF APP/PS MICE AND COGNITIVE DECLINE PROVIDED EVIDENCE THAT ARSENIC EXPOSURE AGGRAVATED AN EXISTING ALZHEIMER'S DISEASE-LIKE PHENOTYPE. WE SHOW DEVELOPMENTAL ARSENIC EXPOSURE SIGNIFICANTLY IMPACTS HISTONE MODIFICATIONS IN BRAIN WHICH REMAIN PRESENT INTO ADULTHOOD AND PROVIDE A POTENTIAL MECHANISM BY WHICH DEVELOPMENTAL ARSENIC EXPOSURE INFLUENCES COGNITIVE FUNCTIONS. WE ALSO SHOW THAT HUMAN RELEVANT, CHRONIC ARSENIC EXPOSURE HAS DELETERIOUS EFFECTS ON ADULT APP/PS MICE AND EXACERBATES EXISTING ALZHEIMER'S DISEASE-LIKE SYMPTOMS. THE RESULTS DEMONSTRATE HOW DEVELOPMENTAL ARSENIC EXPOSURE IMPACTS THE BRAIN EPIGENOME, LEADING TO ALTERED GENE EXPRESSION LATER IN LIFE. 2022 12 2137 35 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 13 2958 38 GENETIC AND EPIGENETIC INSIGHTS INTO FETAL ALCOHOL SPECTRUM DISORDERS. THE MAGNITUDE OF THE DETRIMENTAL EFFECTS FOLLOWING IN UTERO ALCOHOL EXPOSURE, INCLUDING FETAL ALCOHOL SYNDROME AND OTHER FETAL ALCOHOL SPECTRUM DISORDERS (FASD), IS GLOBALLY UNDERESTIMATED. THE EFFECTS INCLUDE IRREVERSIBLE COGNITIVE AND BEHAVIORAL DISABILITIES AS A RESULT OF ABNORMAL BRAIN DEVELOPMENT, PRE- AND POSTNATAL GROWTH RETARDATION AND FACIAL DYSMORPHISM. PARENTAL ALCOHOL EXPOSURE AND ITS EFFECT ON OFFSPRING HAS BEEN RECOGNIZED FOR CENTURIES, BUT ONLY RECENTLY HAVE WE BEGUN TO GAIN MOLECULAR INSIGHT INTO THE MECHANISMS INVOLVED IN ALCOHOL TERATOGENESIS. GENETIC ATTRIBUTES (SUSCEPTIBILITY AND PROTECTIVE ALLELES) OF THE MOTHER AND THE FETUS CONTRIBUTE TO THE RISK OF DEVELOPING FASD AND SPECIFIC ADDITIONAL ENVIRONMENTAL CONDITIONS, INCLUDING MALNUTRITION, HAVE AN IMPORTANT ROLE. THE SEVERITY OF FASD DEPENDS ON THE LEVEL OF ALCOHOL EXPOSURE, THE DEVELOPMENTAL STAGE AT WHICH EXPOSURE OCCURS AND THE NATURE OF THE EXPOSURE (CHRONIC OR ACUTE), AND ALTHOUGH THE MOST VULNERABLE PERIOD IS DURING THE FIRST TRIMESTER, DAMAGE CAN OCCUR THROUGHOUT GESTATION. PRECONCEPTION ALCOHOL EXPOSURE CAN ALSO HAVE A DETRIMENTAL EFFECT ON THE OFFSPRING. SEVERAL DEVELOPMENTAL PATHWAYS ARE AFFECTED IN FASD, INCLUDING NERVOUS SYSTEM DEVELOPMENT, GROWTH AND REMODELING OF TISSUES, AS WELL AS METABOLIC PATHWAYS THAT REGULATE GLUCOCORTICOID SIGNALING AND BALANCED LEVELS OF RETINOL, INSULIN AND NITRIC OXIDE. A BODY OF KNOWLEDGE HAS ACCUMULATED TO SUPPORT THE ROLE OF ENVIRONMENTALLY INDUCED EPIGENETIC REMODELING DURING GAMETOGENESIS AND AFTER CONCEPTION AS A KEY MECHANISM FOR THE TERATOGENIC EFFECTS OF FASD THAT PERSIST INTO ADULTHOOD. TRANSGENERATIONAL EFFECTS ARE LIKELY TO CONTRIBUTE TO THE GLOBAL BURDEN OF ALCOHOL-RELATED DISEASE. FASD RESULTS IN LIFELONG DISABILITY AND PREVENTATIVE PROGRAMS SHOULD INCLUDE BOTH MATERNAL ALCOHOL ABSTENTION AND PRECONCEPTION ALCOHOL AVOIDANCE. 2010 14 2807 32 FETAL PROGRAMMING OF CHRONIC KIDNEY DISEASE: THE ROLE OF MATERNAL SMOKING, MITOCHONDRIAL DYSFUNCTION, AND EPIGENETIC MODFIFICATION. THE ROLE OF AN ADVERSE IN UTERO ENVIRONMENT IN THE PROGRAMMING OF CHRONIC KIDNEY DISEASE IN THE ADULT OFFSPRING IS INCREASINGLY RECOGNIZED. THE CELLULAR AND MOLECULAR MECHANISMS LINKING THE IN UTERO ENVIRONMENT AND FUTURE DISEASE SUSCEPTIBILITY REMAIN UNKNOWN. MATERNAL SMOKING IS A COMMON MODIFIABLE ADVERSE IN UTERO EXPOSURE, POTENTIALLY ASSOCIATED WITH BOTH MITOCHONDRIAL DYSFUNCTION AND EPIGENETIC MODIFICATION IN THE OFFSPRING. WHILE STUDIES ARE EMERGING THAT POINT TOWARD A KEY ROLE OF MITOCHONDRIAL DYSFUNCTION IN ACUTE AND CHRONIC KIDNEY DISEASE, IT MAY HAVE ITS ORIGIN IN EARLY DEVELOPMENT, BECOMING CLINICALLY APPARENT WHEN SECONDARY INSULTS OCCUR. ABERRANT EPIGENETIC PROGRAMMING MAY ADD AN ADDITIONAL LAYER OF COMPLEXITY TO ORCHESTRATE FIBROGENESIS IN THE KIDNEY AND SUSCEPTIBILITY TO CHRONIC KIDNEY DISEASE IN LATER LIFE. IN THIS REVIEW, WE EXPLORE THE EVIDENCE FOR MITOCHONDRIAL DYSFUNCTION AND EPIGENETIC MODIFICATION THROUGH ABERRANT DNA METHYLATION AS KEY MECHANISTIC ASPECTS OF FETAL PROGRAMMING OF CHRONIC KIDNEY DISEASE AND DISCUSS THEIR POTENTIAL USE IN DIAGNOSTICS AND TARGETS FOR THERAPY. 2015 15 2913 20 GENE REGULATORY MECHANISMS UNDERLYING SEX DIFFERENCES IN BRAIN DEVELOPMENT AND PSYCHIATRIC DISEASE. THE SEXUAL DIFFERENTIATION OF THE MAMMALIAN NERVOUS SYSTEM REQUIRES THE PRECISE COORDINATION OF THE TEMPORAL AND SPATIAL REGULATION OF GENE EXPRESSION IN DIVERSE CELL TYPES. SEX HORMONES ACT AT MULTIPLE DEVELOPMENTAL TIME POINTS TO SPECIFY SEX-TYPICAL DIFFERENTIATION DURING EMBRYONIC AND EARLY DEVELOPMENT AND TO COORDINATE SUBSEQUENT RESPONSES TO GONADAL HORMONES LATER IN LIFE BY ESTABLISHING SEX-TYPICAL PATTERNS OF EPIGENETIC MODIFICATIONS ACROSS THE GENOME. THUS, MUTATIONS ASSOCIATED WITH NEUROPSYCHIATRIC CONDITIONS MAY RESULT IN SEXUALLY DIMORPHIC SYMPTOMS BY ACTING ON DIFFERENT NEURAL SUBSTRATES OR CHROMATIN LANDSCAPES IN MALES AND FEMALES. FINALLY, AS STRESS HORMONE SIGNALING MAY DIRECTLY ALTER THE MOLECULAR MACHINERY THAT INTERACTS WITH SEX HORMONE RECEPTORS TO REGULATE GENE EXPRESSION, THE CONTRIBUTION OF CHRONIC STRESS TO THE PATHOGENESIS OR PRESENTATION OF MENTAL ILLNESS MAY BE ADDITIONALLY DIFFERENT BETWEEN THE SEXES. HERE, WE REVIEW THE MECHANISMS THAT CONTRIBUTE TO SEXUAL DIFFERENTIATION IN THE MAMMALIAN NERVOUS SYSTEM AND CONSIDER SOME OF THE IMPLICATIONS OF THESE PROCESSES FOR SEX DIFFERENCES IN NEUROPSYCHIATRIC CONDITIONS. 2018 16 315 33 ALCOHOL, DNA METHYLATION, AND CANCER. CANCER IS ONE OF THE MOST SIGNIFICANT DISEASES ASSOCIATED WITH CHRONIC ALCOHOL CONSUMPTION, AND CHRONIC DRINKING IS A STRONG RISK FACTOR FOR CANCER, PARTICULARLY OF THE UPPER AERODIGESTIVE TRACT, LIVER, COLORECTUM, AND BREAST. SEVERAL FACTORS CONTRIBUTE TO ALCOHOL-INDUCED CANCER DEVELOPMENT (I.E., CARCINOGENESIS), INCLUDING THE ACTIONS OF ACETALDEHYDE, THE FIRST AND PRIMARY METABOLITE OF ETHANOL, AND OXIDATIVE STRESS. HOWEVER, INCREASING EVIDENCE SUGGESTS THAT ABERRANT PATTERNS OF DNA METHYLATION, AN IMPORTANT EPIGENETIC MECHANISM OF TRANSCRIPTIONAL CONTROL, ALSO COULD BE PART OF THE PATHOGENETIC MECHANISMS THAT LEAD TO ALCOHOL-INDUCED CANCER DEVELOPMENT. THE EFFECTS OF ALCOHOL ON GLOBAL AND LOCAL DNA METHYLATION PATTERNS LIKELY ARE MEDIATED BY ITS ABILITY TO INTERFERE WITH THE AVAILABILITY OF THE PRINCIPAL BIOLOGICAL METHYL DONOR, S-ADENOSYLMETHIONINE (SAME), AS WELL AS PATHWAYS RELATED TO IT. SEVERAL MECHANISMS MAY MEDIATE THE EFFECTS OF ALCOHOL ON DNA METHYLATION, INCLUDING REDUCED FOLATE LEVELS AND INHIBITION OF KEY ENZYMES IN ONE-CARBON METABOLISM THAT ULTIMATELY LEAD TO LOWER SAME LEVELS, AS WELL AS INHIBITION OF ACTIVITY AND EXPRESSION OF ENZYMES INVOLVED IN DNA METHYLATION (I.E., DNA METHYLTRANSFERASES). FINALLY, VARIATIONS (I.E., POLYMORPHISMS) OF SEVERAL GENES INVOLVED IN ONE-CARBON METABOLISM ALSO MODULATE THE RISK OF ALCOHOL-ASSOCIATED CARCINOGENESIS. 2013 17 6133 33 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 18 4972 35 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 19 301 32 AIR POLLUTION ASSOCIATED EPIGENETIC MODIFICATIONS: TRANSGENERATIONAL INHERITANCE AND UNDERLYING MOLECULAR MECHANISMS. AIR POLLUTION IS ONE OF THE LEADING CAUSES OF DEATHS IN SOUTHEAST ASIAN COUNTRIES INCLUDING INDIA. EXPOSURE TO AIR POLLUTANTS AFFECTS VITAL CELLULAR MECHANISMS AND IS INTIMATELY LINKED WITH THE ETIOLOGY OF A NUMBER OF CHRONIC DISEASES. EARLIER WORK FROM OUR LABORATORY HAS SHOWN THAT AIRBORNE PARTICULATE MATTER DISTURBS THE MITOCHONDRIAL MACHINERY AND CAUSES SIGNIFICANT DAMAGE TO THE EPIGENOME. MITOCHONDRIAL REACTIVE OXYGEN SPECIES POSSESS THE ABILITY TO TRIGGER REDOX-SENSITIVE SIGNALING MECHANISMS AND INDUCE IRREVERSIBLE EPIGENOMIC CHANGES. THE ELECTROPHILIC NATURE OF REACTIVE METABOLITES CAN DIRECTLY RESULT IN DEPROTONATION OF CYTOSINE AT C-5 POSITION OR INTERFERE WITH THE DNA METHYLTRANSFERASES ACTIVITY TO CAUSE ALTERATIONS IN DNA METHYLATION. IN ADDITION, IT ALSO PERTURBS LEVEL OF CELLULAR METABOLITES CRITICALLY INVOLVED IN DIFFERENT EPIGENETIC PROCESSES LIKE ACETYLATION AND METHYLATION OF HISTONE CODE AND DNA HYPO OR HYPERMETHYLATION. INTERESTINGLY, THESE MODIFICATIONS MAY PERSIST THROUGH DOWNSTREAM GENERATIONS AND RESULT IN THE TRANSGENERATIONAL EPIGENOMIC INHERITANCE. THIS PHENOMENON OF SUBSEQUENT TRANSFER OF EPIGENETIC MODIFICATIONS IS MAINLY ASSOCIATED WITH THE GERM CELLS AND RELIES ON THE GERMLINE STABILITY OF THE EPIGENETIC STATES. OVERALL, THE RECENT LITERATURE SUPPORTS, AND ARGUABLY STRENGTHENS, THE CONTENTION THAT AIR POLLUTION MIGHT CONTRIBUTE TO TRANSMISSION OF EPIMUTATIONS FROM GAMETES TO ZYGOTES BY INVOLVING MITOCHONDRIAL DNA, PARENTAL ALLELE IMPRINTING, HISTONE WITHHOLDING AND NON-CODING RNAS. HOWEVER, LARGER PROSPECTIVE STUDIES USING INNOVATIVE, INTEGRATED EPIGENOME-WIDE METABOLOMIC STRATEGY ARE HIGHLY WARRANTED TO ASSESS THE AIR POLLUTION INDUCED TRANSGENERATIONAL EPIGENETIC INHERITANCE AND ASSOCIATED HUMAN HEALTH EFFECTS. 2019 20 2183 37 EPIGENETIC MECHANISMS RESPONSIBLE FOR THE TRANSGENERATIONAL INHERITANCE OF INTRAUTERINE GROWTH RESTRICTION PHENOTYPES. A POORLY FUNCTIONING PLACENTA RESULTS IN IMPAIRED EXCHANGES OF OXYGEN, NUTRITION, WASTES AND HORMONES BETWEEN THE MOTHER AND HER FETUS. THIS CAN LEAD TO RESTRICTION OF FETAL GROWTH. THESE GROWTH RESTRICTED BABIES ARE AT INCREASED RISK OF DEVELOPING CHRONIC DISEASES, SUCH AS TYPE-2 DIABETES, HYPERTENSION, AND KIDNEY DISEASE, LATER IN LIFE. ANIMAL STUDIES HAVE SHOWN THAT GROWTH RESTRICTED PHENOTYPES ARE SEX-DEPENDENT AND CAN BE TRANSMITTED TO SUBSEQUENT GENERATIONS THROUGH BOTH THE PATERNAL AND MATERNAL LINEAGES. ALTERED EPIGENETIC MECHANISMS, SPECIFICALLY CHANGES IN DNA METHYLATION, HISTONE MODIFICATIONS, AND NON-CODING RNAS THAT REGULATE EXPRESSION OF GENES THAT ARE IMPORTANT FOR FETAL DEVELOPMENT HAVE BEEN SHOWN TO BE ASSOCIATED WITH THE TRANSMISSION PATTERN OF GROWTH RESTRICTED PHENOTYPES. THIS REVIEW WILL DISCUSS THE SUBSEQUENT HEALTH OUTCOMES IN THE OFFSPRING AFTER GROWTH RESTRICTION AND THE TRANSMISSION PATTERNS OF THESE DISEASES. EVIDENCE OF ALTERED EPIGENETIC MECHANISMS IN ASSOCIATION WITH FETAL GROWTH RESTRICTION WILL ALSO BE REVIEWED. 2022