1 3119 152 GESTATIONAL EXPOSURE TO PARTICULATE AIR POLLUTION EXACERBATES THE GROWTH PHENOTYPES INDUCED BY PRECONCEPTION PATERNAL ALCOHOL USE: A MULTIPLEX MODEL OF EXPOSURE. IT IS NOW CLEAR THAT PARENTAL HISTORIES OF DRUG USE, TOXICANT EXPOSURE, AND SOCIAL STRESS ALL HAVE A SIGNIFICANT INFLUENCE ON THE HEALTH AND DEVELOPMENT OF THE NEXT GENERATION. HOWEVER, THE ABILITY OF EPIGENETIC PARENTAL LIFE MEMORIES TO INTERACT WITH SUBSEQUENT GESTATIONAL EXPOSURES AND CUMULATIVELY MODIFY THE DEVELOPMENTAL TRAJECTORY OF THE OFFSPRING REMAINS AN UNEXPLORED PERSPECTIVE IN TOXICOLOGY. STUDIES FROM OUR LABORATORY HAVE IDENTIFIED MALE-SPECIFIC POSTNATAL GROWTH RESTRICTION IN A MOUSE MODEL OF CHRONIC, PRECONCEPTION PATERNAL ALCOHOL EXPOSURE. THE GOAL OF THE CURRENT STUDY WAS TO DETERMINE IF PATERNAL ALCOHOL USE, BEFORE CONCEPTION, COULD MODIFY THE SUSCEPTIBILITY OF THE OFFSPRING TO A COMPLETELY SEPARATE EXPOSURE ENCOUNTERED BY THE MOTHER DURING PREGNANCY. IN INDEPENDENT EXPERIMENTS, WE PREVIOUSLY IDENTIFIED ALTERED DEVELOPMENTAL PROGRAMMING AND INCREASED MARKERS OF SEVERE ASTHMA INDUCED BY GESTATIONAL EXPOSURE TO PARTICULATE AIR POLLUTION. IN THIS STUDY, MALE MICE WERE EXPOSED TO EITHER THE CONTROL OR ALCOHOL PRECONCEPTION TREATMENTS, THEN MATED TO NAIVE FEMALES, WHICH WE SUBSEQUENTLY EXPOSED TO AN ULTRAFINE MIXTURE OF PARTICULATE MATTER VIA INHALATION. INDIVIDUALLY, NEITHER PRECONCEPTION PATERNAL DRINKING NOR GESTATIONAL EXPOSURES TO PARTICULATE AIR POLLUTION IMPACTED THE POSTNATAL GROWTH OF FEMALE OFFSPRING. HOWEVER, WHEN BOTH EXPOSURES WERE COMBINED, FEMALES DISPLAYED A 30% REDUCTION IN WEIGHT GAIN. UNEXPECTEDLY, THIS EXPOSURE PARADIGM RESULTED IN A DRAMATIC POSTNATAL INCREASE IN LITTER LOSS DUE TO MATERNAL CANNIBALISM, WHICH PREVENTED ADDITIONAL MEASURES OF OFFSPRING HEALTH. THESE PRELIMINARY STUDIES PROVIDE EVIDENCE OF A COMPLEX INTERPLAY BETWEEN PRECONCEPTION LIFE HISTORY AND INTRAUTERINE ENVIRONMENTAL FACTORS IN THE CONTROL OF POSTNATAL GROWTH. 2020 2 5166 57 PRECONCEPTION PATERNAL ALCOHOL EXPOSURE EXERTS SEX-SPECIFIC EFFECTS ON OFFSPRING GROWTH AND LONG-TERM METABOLIC PROGRAMMING. BACKGROUND: ALTHOUGH CLINICAL DATA SUPPORT AN ASSOCIATION BETWEEN PATERNAL ALCOHOL USE AND DEFICITS IN CHILD NEUROCOGNITIVE DEVELOPMENT, THE RELATIONSHIP BETWEEN PATERNAL DRINKING AND ALCOHOL-INDUCED GROWTH PHENOTYPES REMAINS CHALLENGING TO DEFINE. USING AN ESTABLISHED MOUSE MODEL OF CHRONIC EXPOSURE, PREVIOUS WORK BY OUR GROUP HAS LINKED PRECONCEPTION PATERNAL ALCOHOL USE TO SEX-SPECIFIC PATTERNS OF FETAL GROWTH RESTRICTION AND PLACENTAL DYSFUNCTION. THE AIM OF THE PRESENT STUDY WAS TO INVESTIGATE THE LONG-TERM IMPACT OF CHRONIC PRECONCEPTION PATERNAL ALCOHOL USE ON OFFSPRING GROWTH AND METABOLIC PROGRAMMING. RESULTS: PRECONCEPTION PATERNAL ALCOHOL EXPOSURE INDUCED A PROLONGED PERIOD OF FETAL GESTATION AND AN INCREASED INCIDENCE OF INTRAUTERINE GROWTH RESTRICTION, WHICH AFFECTED THE MALE OFFSPRING TO A GREATER EXTENT THAN THE FEMALES. WHILE THE FEMALE OFFSPRING OF ETHANOL-EXPOSED MALES WERE ABLE TO MATCH THE BODY WEIGHTS OF THE CONTROLS WITHIN THE FIRST 2 WEEKS OF POSTNATAL LIFE, MALE OFFSPRING CONTINUED TO DISPLAY AN 11% REDUCTION IN WEIGHT AT 5 WEEKS OF AGE AND A 6% REDUCTION AT 8 WEEKS OF AGE. THE OBSERVED GROWTH DEFICITS ASSOCIATED WITH INSULIN HYPERSENSITIVITY IN THE MALE OFFSPRING, WHILE IN CONTRAST, FEMALES DISPLAYED A MODEST LAG IN THEIR GLUCOSE TOLERANCE TEST. THESE METABOLIC DEFECTS WERE ASSOCIATED WITH AN UP-REGULATION OF GENES WITHIN THE PRO-FIBROTIC TGF-BETA SIGNALING PATHWAY AND INCREASED LEVELS OF CELLULAR HYDROXYPROLINE WITHIN THE LIVERS OF THE MALE OFFSPRING. WE OBSERVED SUPPRESSED CYTOKINE PROFILES WITHIN THE LIVER AND PANCREAS OF BOTH THE MALE AND FEMALE OFFSPRING, WHICH CORRELATED WITH THE UP-REGULATION OF GENES IN THE LIVERX/RETINOIDX/FARNESOIDX RECEPTOR PATHWAYS. HOWEVER, PATTERNS OF GENE EXPRESSION WERE HIGHLY VARIABLE BETWEEN THE OFFSPRING OF ALCOHOL-EXPOSED SIRES. IN THE ADULT OFFSPRING OF ALCOHOL-EXPOSED MALES, WE DID NOT OBSERVE ANY DIFFERENCES IN THE ALLELIC EXPRESSION OF IGF2 OR ANY OTHER IMPRINTED GENES. CONCLUSIONS: THE IMPACT OF PATERNAL ALCOHOL USE ON CHILD DEVELOPMENT IS POORLY EXPLORED AND REPRESENTS A SIGNIFICANT GAP IN OUR UNDERSTANDING OF THE TERATOGENIC EFFECTS OF ETHANOL. OUR STUDIES IMPLICATE PATERNAL EXPOSURE HISTORY AS AN ADDITIONAL AND IMPORTANT MODIFIER OF ALCOHOL-INDUCED GROWTH PHENOTYPES AND CHALLENGE THE CURRENT MATERNAL-CENTRIC EXPOSURE PARADIGM. 2019 3 4941 36 PATERNAL OBESITY, INTERVENTIONS, AND MECHANISTIC PATHWAYS TO IMPAIRED HEALTH IN OFFSPRING. BACKGROUND: THE GLOBAL RATES OF MALE OVERWEIGHT/OBESITY ARE RISING, APPROACHING 70% OF THE TOTAL ADULT POPULATION IN WESTERN NATIONS. OVERWEIGHT/OBESITY INCREASES THE RISK OF CHRONIC DISEASES; HOWEVER, THERE IS INCREASING AWARENESS THAT MALE OBESITY NEGATIVELY IMPACTS FERTILITY, SUBSEQUENT PREGNANCY, AND THE OFFSPRING HEALTH BURDEN. DEVELOPMENTAL PROGRAMMING IS WELL DEFINED IN MOTHERS; HOWEVER, IT IS BECOMING INCREASINGLY EVIDENT THAT DEVELOPMENTAL PROGRAMMING CAN BE PATERNALLY INITIATED AND MEDIATED THROUGH PATERNAL OBESITY. KEY MESSAGES: BOTH HUMAN AND RODENT MODELS HAVE ESTABLISHED THAT PATERNAL OBESITY IMPAIRS SEX HORMONES, BASIC SPERM FUNCTION, AND MOLECULAR COMPOSITION. THIS RESULTS IN PERTURBED EMBRYO DEVELOPMENT AND HEALTH AND AN INCREASED SUBSEQUENT OFFSPRING DISEASE BURDEN IN BOTH SEXES. THE REVERSIBILITY OF OBESITY-INDUCED PARENTAL PROGRAMMING HAS ONLY RECENTLY RECEIVED ATTENTION. PROMISING RESULTS IN ANIMAL MODELS UTILIZING DIET AND EXERCISE INTERVENTIONS HAVE SHOWN IMPROVEMENTS IN SPERM FUNCTION AND MOLECULAR COMPOSITION, RESULTING IN RESTORATIONS OF BOTH EMBRYO AND FETAL HEALTH AND SUBSEQUENT MALE OFFSPRING FERTILITY. THE DIRECT MODE FOR PATERNAL INHERITANCE IS LIKELY MEDIATED VIA SPERMATOZOA. WE PROPOSE TWO MAIN THEORIES FOR THE ORIGIN OF MALE OBESITY-INDUCED PATERNAL PROGRAMMING: (1) ACCUMULATION OF SPERM DNA DAMAGE RESULTING IN DE NOVO MUTATIONS IN THE EMBRYO AND (2) CHANGES IN SPERM EPIGENETIC MARKS (MICRORNA, METHYLATION, OR ACETYLATION) ALTERING THE ACCESS, TRANSCRIPTION, AND TRANSLATION OF PATERNALLY DERIVED GENES DURING EARLY EMBRYOGENESIS. CONCLUSIONS: PATERNAL OVERWEIGHT/OBESITY INDUCES PATERNAL PROGRAMMING OF OFFSPRING PHENOTYPES LIKELY MEDIATED THROUGH GENETIC AND EPIGENETIC CHANGES IN SPERMATOZOA. THESE PROGRAMMED CHANGES TO OFFSPRING HEALTH APPEAR TO BE PARTIALLY RESTORED VIA DIET/EXERCISE INTERVENTIONS IN OBESE FATHERS PRECONCEPTION, WHICH HAVE BEEN SHOWN TO IMPROVE ASPECTS OF SPERM DNA INTEGRITY. HOWEVER, THE MAJORITY OF DATA SURROUNDING PATERNAL OBESITY AND OFFSPRING PHENOTYPES HAVE COME FROM RODENT MODELS; THEREFORE, WE CONTEND THAT IT WILL BE INCREASINGLY IMPORTANT TO STUDY POPULATION-BASED DATA TO DETERMINE THE LIKELY MODE OF INHERITANCE IN HUMANS. 2014 4 5168 37 PRECONCEPTIONAL PATERNAL EXPOSURE TO A SINGLE TRAUMATIC EVENT AFFECTS POSTNATAL GROWTH OF FEMALE BUT NOT MALE OFFSPRING. ALTHOUGH PRECONCEPTIONAL AND PERICONCEPTIONAL MATERNAL STRESS IS A RECOGNIZED RISK FACTOR FOR OFFSPRING NEURODEVELOPMENTAL DISTURBANCES, LESS IS KNOWN ABOUT THE RELEVANCE OF PATERNAL EXPOSURES. THESE HAVE HITHERTO BEEN INVESTIGATED MAINLY WITH RESPECT TO SUBSTANCE-INDUCED IMPAIRMENT IN THE PROGENY. IN RECENT YEARS, EXPERIENTIAL INFLUENCES ON OFFSPRING HAVE COME INTO FOCUS THROUGH GROWING INSIGHT INTO EPIGENETIC MECHANISMS SUCH AS NONGENETIC MODES OF TRANSMISSION. THE EFFECT OF CHRONIC AND/OR EARLY MANIPULATIONS IN MALES HAS BEEN STUDIED BUT MUCH LESS IS KNOWN ABOUT THE POTENTIAL IMPACT OF SINGULAR MANIPULATIONS IN OLDER INDIVIDUALS. WE INVESTIGATED THE INFLUENCE OF A STRONG STRESSOR EXPOSURE, REMINISCENT OF A TRAUMATIC EVENT, IN ADULT MALE MICE ON OFFSPRING BEHAVIOR. MALE MICE, 6 WEEKS OF AGE, RECEIVED A STRONG FOOTSHOCK AND WERE MATED TO NAIVE FEMALES SEVERAL WEEKS LATER. MALE AND FEMALE OFFSPRING WERE INVESTIGATED IN A VARIETY OF TESTS FOR ANXIETY-LIKE AND DEPRESSION-LIKE BEHAVIORS. IN ADDITION, BODYWEIGHT DEVELOPMENT WAS ASSESSED. ALTHOUGH WE DID NOT OBSERVE ANY ALTERATIONS IN ANXIETY-LIKE AND DEPRESSIVE-LIKE BEHAVIORAL INDICES, WE RECORDED REDUCED BODYWEIGHT DEVELOPMENT IN THE FEMALE OFFSPRING. OUR DATA EMPHASIZE THE RELEVANCE OF SEX AS A (CO)DETERMINANT OF OUTCOMES IN THE WAKE OF PARENTAL MANIPULATIONS. THEY FURTHER SUGGEST THAT THE WINDOW OF VULNERABILITY FOR THE INDUCTION OF PATRILINEAR EFFECTS MIGHT BE WIDER THAN THAT CURRENTLY ASSUMED. 2013 5 4064 41 MATERNAL AND EARLY-LIFE CIRCADIAN DISRUPTION HAVE LONG-LASTING NEGATIVE CONSEQUENCES ON OFFSPRING DEVELOPMENT AND ADULT BEHAVIOR IN MICE. MODERN LIFE INVOLVES CHRONIC CIRCADIAN DISRUPTION THROUGH ARTIFICIAL LIGHT AND THESE DISRUPTIONS ARE ASSOCIATED WITH NUMEROUS MENTAL AND PHYSICAL HEALTH MALADIES. BECAUSE THE DEVELOPING NERVOUS SYSTEM IS PARTICULARLY VULNERABLE TO PERTURBATION, WE HYPOTHESIZED THAT EARLY-LIFE CIRCADIAN DISRUPTION WOULD NEGATIVELY IMPACT OFFSPRING DEVELOPMENT AND ADULT FUNCTION. PREGNANT MICE WERE SUBJECTED TO CHRONIC CIRCADIAN DISRUPTION FROM THE TIME OF UTERINE IMPLANTATION THROUGH WEANING. TO DISSOCIATE IN UTERO FROM POSTNATAL EFFECTS, A SUBSET OF LITTERS WAS CROSS-FOSTERED AT BIRTH FROM DISRUPTED DAMS TO CONTROL DAMS AND VICE VERSA. POSTNATAL CIRCADIAN DISRUPTION WAS ASSOCIATED WITH REDUCED ADULT BODY MASS, SOCIAL AVOIDANCE, AND HYPERACTIVITY. IN UTERO DISRUPTION RESULTED IN MORE PRONOUNCED SOCIAL AVOIDANCE AND HYPERACTIVITY, PHENOTYPES NOT ABROGATED BY CROSS-FOSTERING TO CONTROL MOTHERS. TO EXAMINE WHETHER CIRCADIAN DISRUPTION AFFECTS DEVELOPMENT BY ACTING AS AN EARLY LIFE STRESSOR, WE EXAMINED BIRTHWEIGHT, LITTER SIZE, MATERNAL CANNIBALISM, AND EPIGENETIC MODIFICATIONS. NONE OF THESE VARIABLES DIFFERED BETWEEN CONTROL AND DISRUPTED DAMS, OR RESEMBLED PATTERNS SEEN FOLLOWING EARLY-LIFE STRESS. OUR FINDINGS INDICATE THAT DEVELOPMENTAL CHRONIC CIRCADIAN DISRUPTION PERMANENTLY AFFECTS SOMATIC AND BEHAVIORAL DEVELOPMENT IN A STAGE-OF-LIFE-DEPENDENT MANNER, INDEPENDENT OF EARLY LIFE STRESS MECHANISMS, UNDERSCORING THE IMPORTANCE OF TEMPORAL STRUCTURE DURING DEVELOPMENT, BOTH IN UTERO AND EARLY POSTNATAL LIFE. 2017 6 6426 29 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 7 4942 28 PATERNAL OBESITY: HOW BAD IS IT FOR SPERM QUALITY AND PROGENY HEALTH? THERE IS SUBSTANTIAL EVIDENCE THAT PATERNAL OBESITY IS ASSOCIATED NOT ONLY WITH AN INCREASED INCIDENCE OF INFERTILITY, BUT ALSO WITH AN INCREASED RISK OF METABOLIC DISTURBANCE IN ADULT OFFSPRING. APPARENTLY, SEVERAL MECHANISMS MAY CONTRIBUTE TO THE SPERM QUALITY ALTERATIONS ASSOCIATED WITH PATERNAL OBESITY, SUCH AS PHYSIOLOGICAL/HORMONAL ALTERATIONS, OXIDATIVE STRESS, AND EPIGENETIC ALTERATIONS. ALONG THESE LINES, MODIFICATIONS OF HORMONAL PROFILES NAMELY REDUCED ANDROGEN LEVELS AND ELEVATED ESTROGEN LEVELS, WERE FOUND ASSOCIATED WITH LOWER SPERM CONCENTRATION AND SEMINAL VOLUME. ADDITIONALLY, OXIDATIVE STRESS IN TESTIS MAY INDUCE AN INCREASE OF THE PERCENTAGE OF SPERM WITH DNA FRAGMENTATION. THE LATTER, RELATE TO OTHER PECULIARITIES SUCH AS ALTERATION OF THE EMBRYONIC DEVELOPMENT, INCREASED RISK OF MISCARRIAGE, AND DEVELOPMENT OF CHRONIC MORBIDITY IN THE OFFSPRING, INCLUDING CHILDHOOD CANCERS. UNDOUBTEDLY, EPIGENETIC ALTERATIONS (IE, DNA METHYLATION, CHROMATIN MODIFICATIONS, AND SMALL RNA DEREGULATION) OF SPERM RELATED TO PATERNAL OBESITY AND THEIR CONSEQUENCES ON THE PROGENY ARE POORLY UNDERSTOOD DETERMINANTS OF PATERNAL OBESITY-INDUCED TRANSMISSION. IN THIS REVIEW, WE SUMMARIZE AND DISCUSS THE DATA AVAILABLE IN THE LITERATURE REGARDING THE BIOLOGICAL, PHYSIOLOGICAL, AND MOLECULAR CONSEQUENCES OF PATERNAL OBESITY ON MALE FERTILITY POTENTIAL AND ULTIMATELY PROGENY HEALTH. 2017 8 4011 33 LOW PATERNAL DIETARY FOLATE ALTERS THE MOUSE SPERM EPIGENOME AND IS ASSOCIATED WITH NEGATIVE PREGNANCY OUTCOMES. EPIDEMIOLOGICAL STUDIES SUGGEST THAT A FATHER'S DIET CAN INFLUENCE OFFSPRING HEALTH. A PROPOSED MECHANISM FOR PATERNAL TRANSMISSION OF ENVIRONMENTAL INFORMATION IS VIA THE SPERM EPIGENOME. THE EPIGENOME INCLUDES HERITABLE INFORMATION SUCH AS DNA METHYLATION. WE HYPOTHESIZE THAT THE DIETARY SUPPLY OF METHYL DONORS WILL ALTER EPIGENETIC REPROGRAMMING IN SPERM. HERE WE FEED MALE MICE EITHER A FOLATE-DEFICIENT OR FOLATE-SUFFICIENT DIET THROUGHOUT LIFE. PATERNAL FOLATE DEFICIENCY IS ASSOCIATED WITH INCREASED BIRTH DEFECTS IN THE OFFSPRING, WHICH INCLUDE CRANIOFACIAL AND MUSCULOSKELETAL MALFORMATIONS. GENOME-WIDE DNA METHYLATION ANALYSIS AND THE SUBSEQUENT FUNCTIONAL ANALYSIS IDENTIFY DIFFERENTIAL METHYLATION IN SPERM OF GENES IMPLICATED IN DEVELOPMENT, CHRONIC DISEASES SUCH AS CANCER, DIABETES, AUTISM AND SCHIZOPHRENIA. WHILE >300 GENES ARE DIFFERENTIALLY EXPRESSED IN OFFSPRING PLACENTA, ONLY TWO CORRESPOND TO GENES WITH DIFFERENTIAL METHYLATION IN SPERM. THIS MODEL SUGGESTS EPIGENETIC TRANSMISSION MAY INVOLVE SPERM HISTONE H3 METHYLATION OR DNA METHYLATION AND THAT ADEQUATE PATERNAL DIETARY FOLATE IS ESSENTIAL FOR OFFSPRING HEALTH. 2013 9 2472 30 EPIGENETIC TRANSMISSION OF THE IMPACT OF EARLY STRESS ACROSS GENERATIONS. BACKGROUND: TRAUMATIC EXPERIENCES IN EARLY LIFE ARE RISK FACTORS FOR THE DEVELOPMENT OF BEHAVIORAL AND EMOTIONAL DISORDERS. SUCH DISORDERS CAN PERSIST THROUGH ADULTHOOD AND HAVE OFTEN BEEN REPORTED TO BE TRANSMITTED ACROSS GENERATIONS. METHODS: TO INVESTIGATE THE TRANSGENERATIONAL EFFECT OF EARLY STRESS, MICE WERE EXPOSED TO CHRONIC AND UNPREDICTABLE MATERNAL SEPARATION FROM POSTNATAL DAY 1 TO 14. RESULTS: WE SHOW THAT CHRONIC AND UNPREDICTABLE MATERNAL SEPARATION INDUCES DEPRESSIVE-LIKE BEHAVIORS AND ALTERS THE BEHAVIORAL RESPONSE TO AVERSIVE ENVIRONMENTS IN THE SEPARATED ANIMALS WHEN ADULT. MOST OF THE BEHAVIORAL ALTERATIONS ARE FURTHER EXPRESSED BY THE OFFSPRING OF MALES SUBJECTED TO MATERNAL SEPARATION, DESPITE THE FACT THAT THESE MALES ARE REARED NORMALLY. CHRONIC AND UNPREDICTABLE MATERNAL SEPARATION ALSO ALTERS THE PROFILE OF DNA METHYLATION IN THE PROMOTER OF SEVERAL CANDIDATE GENES IN THE GERMLINE OF THE SEPARATED MALES. COMPARABLE CHANGES IN DNA METHYLATION ARE ALSO PRESENT IN THE BRAIN OF THE OFFSPRING AND ARE ASSOCIATED WITH ALTERED GENE EXPRESSION. CONCLUSIONS: THESE FINDINGS HIGHLIGHT THE NEGATIVE IMPACT OF EARLY STRESS ON BEHAVIORAL RESPONSES ACROSS GENERATIONS AND ON THE REGULATION OF DNA METHYLATION IN THE GERMLINE. 2010 10 4496 39 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 11 4065 40 MATERNAL AND GESTATIONAL INFLUENCES ON CHILDHOOD BLOOD PRESSURE. EXPOSURES THAT CONTRIBUTE TO A SUB-OPTIMAL INTRAUTERINE ENVIRONMENT CAN HAVE AN EFFECT ON THE DEVELOPING FETUS. IMPAIRED FETAL GROWTH THAT RESULTS IN LOW BIRTH WEIGHT IS AN ESTABLISHED RISK FACTOR FOR CARDIO-METABOLIC DISORDERS LATER IN LIFE. RECENT EPIDEMIOLOGIC AND PROSPECTIVE COHORT STUDIES THAT INCLUDE THE MATERNAL AND GESTATIONAL PERIOD HAVE IDENTIFIED MATERNAL AND GESTATIONAL CONDITIONS THAT CONFER INCREASED RISK FOR SUBSEQUENT CARDIO-METABOLIC DISORDERS IN THE ABSENCE OF LOW BIRTH WEIGHT. MATERNAL PRE-CONCEPTION HEALTH STATUS, INCLUDING CHRONIC OBESITY AND TYPE 2 DIABETES, INCREASE RISK FOR CHILDHOOD OBESITY AND OBESITY-RELATED HIGHER BLOOD PRESSURE (BP) IN CHILD OFFSPRING. MATERNAL GESTATIONAL EXPOSURES, INCLUDING GESTATIONAL DIABETES, GESTATIONAL HYPERTENSION, AND PREECLAMPSIA, ARE ASSOCIATED WITH HIGHER BP IN OFFSPRING. OTHER MATERNAL EXPOSURES SUCH AS CIGARETTE SMOKE AND AIR POLLUTION ALSO INCREASE RISK FOR HIGHER BP IN CHILD OFFSPRING. RECENT, BUT LIMITED, DATA INDICATE THAT ASSISTED REPRODUCTIVE TECHNOLOGIES CAN BE ASSOCIATED WITH HYPERTENSION IN CHILDHOOD, DESPITE OTHERWISE NORMAL GESTATION AND HEALTHY NEWBORN. GESTATIONAL EXPOSURES ASSOCIATED WITH HIGHER BP IN CHILDHOOD CAN BE RELATED TO FAMILIAL LIFESTYLE FACTORS, GENETICS, OR EPIGENETIC MODIFICATION OF FETAL DEOXYRIBONUCLEIC ACID (DNA). THESE FACTORS, OR COMBINATION OF FACTORS, AS WELL AS OTHER ADVERSE INTRAUTERINE CONDITIONS, COULD INDUCE FETAL PROGRAMING LEADING TO HEALTH CONSEQUENCES IN LATER LIFE. CURRENT AND DEVELOPING RESEARCH WILL PROVIDE ADDITIONAL INSIGHTS ON GESTATIONAL EXPOSURES AND FETAL ADJUSTMENTS THAT INCREASE RISK FOR HIGHER BP LEVELS IN CHILDHOOD. 2020 12 5397 39 REDUCED LEVELS OF MIRNAS 449 AND 34 IN SPERM OF MICE AND MEN EXPOSED TO EARLY LIFE STRESS. EXPOSURE OF MALE MICE TO EARLY LIFE STRESS ALTERS THE LEVELS OF SPECIFIC SPERM MIRNAS THAT PROMOTE STRESS-ASSOCIATED BEHAVIORS IN THEIR OFFSPRING. TO BEGIN TO EVALUATE WHETHER SIMILAR PHENOMENA OCCUR IN MEN, WE SEARCHED FOR SPERM MIRNA CHANGES THAT OCCUR IN BOTH MICE AND MEN EXPOSED TO EARLY LIFE STRESSORS THAT HAVE LONG-LASTING EFFECTS. FOR MEN, WE USED THE ADVERSE CHILDHOOD EXPERIENCE (ACE) QUESTIONNAIRE. IT REVEALS THE DEGREE OF ABUSIVE AND/OR DYSFUNCTIONAL FAMILY EXPERIENCES WHEN YOUNG, WHICH INCREASES RISKS OF DEVELOPING FUTURE PSYCHOLOGICAL AND PHYSICAL DISORDERS. FOR MALE MICE, WE USED ADOLESCENT CHRONIC SOCIAL INSTABILITY (CSI) STRESS, WHICH NOT ONLY ENHANCES SOCIABILITY DEFECTS FOR >1 YEAR, BUT ALSO ANXIETY AND DEFECTIVE SOCIABILITY IN FEMALE OFFSPRING FOR MULTIPLE GENERATIONS THROUGH THE MALE LINEAGE. HERE WE FOUND A STATISTICALLY SIGNIFICANT INVERSE CORRELATION BETWEEN LEVELS OF MULTIPLE MIRNAS OF THE MIR-449/34 FAMILY AND ACE SCORES OF CAUCASIAN MALES. REMARKABLY, WE FOUND MEMBERS OF THE SAME SPERM MIRNA FAMILY ARE ALSO REDUCED IN MICE EXPOSED TO CSI STRESS. THUS, FUTURE STUDIES SHOULD BE DESIGNED TO DIRECTLY TEST WHETHER REDUCED LEVELS OF THESE MIRNAS COULD BE USED AS UNBIASED INDICATORS OF CURRENT AND/OR EARLY LIFE EXPOSURE TO SEVERE STRESS. MOREOVER, AFTER MATING STRESSED MALE MICE, THESE SPERM MIRNA REDUCTIONS PERSIST IN BOTH EARLY EMBRYOS THROUGH AT LEAST THE MORULA STAGE AND IN SPERM OF MALES DERIVED FROM THEM, SUGGESTING THESE MIRNA CHANGES CONTRIBUTE TO TRANSMISSION OF STRESS PHENOTYPES ACROSS GENERATIONS. SINCE OFFSPRING OF MEN EXPOSED TO EARLY LIFE TRAUMA HAVE ELEVATED RISKS FOR PSYCHOLOGICAL DISORDERS, THESE FINDINGS RAISE THE POSSIBILITY THAT A PORTION OF THIS RISK MAY BE DERIVED FROM EPIGENETIC REGULATION OF THESE SPERM MIRNAS. 2018 13 4767 35 NUCLEAR AND MITOCHONDRIAL DNA ALTERATIONS IN NEWBORNS WITH PRENATAL EXPOSURE TO CIGARETTE SMOKE. NEWBORNS EXPOSED TO MATERNAL CIGARETTE SMOKE (CS) IN UTERO HAVE AN INCREASED RISK OF DEVELOPING CHRONIC DISEASES, CANCER, AND ACQUIRING DECREASED COGNITIVE FUNCTION IN ADULTHOOD. ALTHOUGH THE LITERATURE REPORTS MANY DELETERIOUS EFFECTS ASSOCIATED WITH MATERNAL CIGARETTE SMOKING ON THE FETUS, THE MOLECULAR ALTERATIONS AND MECHANISMS OF ACTION ARE NOT YET CLEAR. SMOKING MAY ACT DIRECTLY ON NUCLEAR DNA BY INDUCING MUTATIONS OR EPIGENETIC MODIFICATIONS. RECENT STUDIES ALSO INDICATE THAT SMOKING MAY ACT ON MITOCHONDRIAL DNA BY INDUCING A CHANGE IN THE NUMBER OF COPIES TO MAKE UP FOR THE DAMAGE CAUSED BY SMOKING ON THE RESPIRATORY CHAIN AND LACK OF ENERGY. IN ADDITION, INDIVIDUAL GENETIC SUSCEPTIBILITY PLAYS A SIGNIFICANT ROLE IN DETERMINING THE EFFECTS OF SMOKING DURING DEVELOPMENT. FURTHERMORE, PRIOR EXPOSURE OF PATERNAL AND MATERNAL GAMETES TO CIGARETTE SMOKE MAY AFFECT THE HEALTH OF THE DEVELOPING INDIVIDUAL, NOT ONLY THE IN UTERO EXPOSURE. THIS REVIEW EXAMINES THE GENETIC AND EPIGENETIC ALTERATIONS IN NUCLEAR AND MITOCHONDRIAL DNA ASSOCIATED WITH SMOKE EXPOSURE DURING THE MOST SENSITIVE PERIODS OF DEVELOPMENT (PRIOR TO CONCEPTION, PRENATAL AND EARLY POSTNATAL) AND ASSESSES HOW SUCH CHANGES MAY HAVE CONSEQUENCES FOR BOTH FETAL GROWTH AND DEVELOPMENT. 2015 14 6554 27 TRANSGENERATIONAL EFFECTS OF EARLY ENVIRONMENTAL INSULTS ON AGING AND DISEASE INCIDENCE. ADVERSE EARLY LIFE EXPERIENCES ARE MAJOR INFLUENCES ON DEVELOPMENTAL TRAJECTORIES WITH POTENTIALLY LIFE-LONG CONSEQUENCES. PRENATAL OR EARLY POSTNATAL EXPOSURE TO STRESS, UNDERNUTRITION OR ENVIRONMENTAL TOXICANTS MAY REPROGRAM BRAIN DEVELOPMENT AND INCREASE RISK OF BEHAVIOURAL AND NEUROLOGICAL DISORDERS LATER IN LIFE. NOT ONLY EXPERIENCE WITHIN A SINGLE LIFETIME, BUT ALSO ANCESTRAL EXPERIENCE AFFECTS HEALTH TRAJECTORIES AND CHANCES OF SUCCESSFUL AGING. THE CENTRAL MECHANISM IN TRANSGENERATIONAL PROGRAMMING OF A DISEASE MAY BE THE FORMATION OF EPIGENETIC MEMORY. THIS REVIEW EXPLORES TRANSGENERATIONAL EFFECTS OF EARLY ADVERSE EXPERIENCE ON HEALTH AND DISEASE INCIDENCE IN OLDER AGE. FIRST, WE ADDRESS MECHANISMS OF DEVELOPMENTAL AND TRANSGENERATIONAL PROGRAMMING OF DISEASE AND INHERITANCE. SECOND, WE DISCUSS EXPERIMENTAL AND CLINICAL FINDINGS LINKING EARLY ENVIRONMENTAL DETERMINANTS TO ADVERSE AGING TRAJECTORIES IN ASSOCIATION WITH POSSIBLE PARENTAL CONTRIBUTIONS AND SEX-SPECIFIC EFFECTS. THIRD, WE OUTLINE THE MAIN MECHANISMS OF AGE-RELATED FUNCTIONAL DECLINE AND SUGGEST POTENTIAL INTERVENTIONS TO REVERSE NEGATIVE EFFECTS OF TRANSGENERATIONAL PROGRAMMING. THUS, STRATEGIES THAT SUPPORT HEALTHY DEVELOPMENT AND SUCCESSFUL AGING SHOULD TAKE INTO ACCOUNT THE POTENTIAL INFLUENCES OF TRANSGENERATIONAL INHERITANCE. 2020 15 6234 44 THE LONG-TERM EFFECTS OF PRENATAL DEVELOPMENT ON GROWTH AND METABOLISM. PEOPLE WHO WERE SMALL AT BIRTH AND HAD POOR INFANT GROWTH HAVE AN INCREASED RISK OF ADULT CARDIOVASCULAR DISEASE, OSTEOPOROSIS, AND TYPE 2 DIABETES, PARTICULARLY IF THEIR RESTRICTED EARLY GROWTH WAS FOLLOWED BY INCREASED CHILDHOOD WEIGHT GAIN. THESE RELATIONS EXTEND ACROSS THE NORMAL RANGE OF BIRTH SIZE IN A GRADED MANNER, SO REDUCED SIZE IS NOT A PREREQUISITE. IN ADDITION, LARGER BIRTH SIZE IS ASSOCIATED WITH RISKS OF OBESITY AND TYPE 2 DIABETES. THE ASSOCIATIONS APPEAR TO REFLECT DEVELOPMENTAL PLASTIC RESPONSES MADE BY THE FETUS AND INFANT BASED ON CUES ABOUT THE ENVIRONMENT, INFLUENCED BY MATERNAL CHARACTERISTICS INCLUDING DIET, BODY COMPOSITION, STRESS, AND EXERCISE LEVELS. THESE RESPONSES INVOLVE EPIGENETIC PROCESSES THAT MODIFY THE OFFSPRING'S PHENOTYPE. VULNERABILITY TO ILL HEALTH RESULTS IF THE ENVIRONMENT IN INFANCY, CHILDHOOD, AND LATER LIFE IS MISMATCHED TO THE PHENOTYPE INDUCED IN DEVELOPMENT, INFORMED BY THE DEVELOPMENTAL CUES. THIS MISMATCH MAY ARISE THROUGH UNBALANCED DIET OR BODY COMPOSITION OF THE MOTHER OR A CHANGE IN LIFESTYLE FACTORS BETWEEN GENERATIONS. THESE INSIGHTS OFFER NEW POSSIBILITIES FOR THE EARLY DIAGNOSIS AND PREVENTION OF CHRONIC DISEASE. 2011 16 2958 36 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 17 4223 35 METHYLATION CHANGES AT NR3C1 IN NEWBORNS ASSOCIATE WITH MATERNAL PRENATAL STRESS EXPOSURE AND NEWBORN BIRTH WEIGHT. EARLY LIFE EXPERIENCES, INCLUDING THOSE IN UTERO, HAVE BEEN LINKED TO INCREASED RISK FOR ADULT-ONSET CHRONIC DISEASE. THE UNDERLYING ASSUMPTION IS THAT THERE IS A CRITICAL PERIOD OF DEVELOPMENTAL PLASTICITY IN UTERO WHEN SELECTION OF THE FETAL PHENOTYPE THAT IS BEST ADAPTED TO THE INTRAUTERINE ENVIRONMENT OCCURS. THE CURRENT STUDY IS THE FIRST TO TEST THE IDEA THAT EXTREME MATERNAL PSYCHOSOCIAL STRESSORS, AS OBSERVED IN THE DEMOCRATIC REPUBLIC OF CONGO, MAY MODIFY LOCUS-SPECIFIC EPIGENETIC MARKS IN THE NEWBORN RESULTING IN ALTERED HEALTH OUTCOMES. HERE WE SHOW A SIGNIFICANT CORRELATION BETWEEN CULTURALLY RELEVANT MEASURES OF MATERNAL PRENATAL STRESS, NEWBORN BIRTH WEIGHT AND NEWBORN METHYLATION IN THE PROMOTER OF THE GLUCOCORTICOID RECEPTOR NR3C1. INCREASED METHYLATION MAY CONSTRAIN PLASTICITY IN SUBSEQUENT GENE EXPRESSION AND RESTRICT THE RANGE OF STRESS ADAPTATION RESPONSES POSSIBLE IN AFFECTED INDIVIDUALS, THUS INCREASING THEIR RISK FOR ADULT-ONSET DISEASES. 2012 18 6781 53 [BREATHING: AMBIENT AIR POLLUTION AND HEALTH - PART III]. THE THIRD PART OF THE DGP STATEMENT INTRODUCES THE CURRENT BODY OF KNOWLEDGE ON LESS STUDIED HEALTH OUTCOMES ASSOCIATED WITH EXPOSURE TO AMBIENT AIR POLLUTION: THE NEGATIVE IMPACT ON METABOLISM LEADING TO IMPAIRED GLUCOSE TOLERANCE AND DIABETES AS WELL AS CONTRIBUTION TO THE DEVELOPMENT OF NEURODEGENERATIVE DISORDERS AND DELAYED COGNITIVE FUNCTION IN CHILDREN. FURTHERMORE, PRENATAL EXPOSURE AND ADVERSE EFFECTS ON MOTHER AND CHILD ARE ADDRESSED. FINALLY, THE CURRENTLY DISCUSSED BIOLOGICAL MECHANISMS UNDERLYING VARIOUS HEALTH EFFECTS ASSOCIATED WITH EXPOSURE TO AIR POLLUTION ARE DESCRIBED.DIFFERING, BUT OFTEN COMPLEMENTARY BIOLOGICAL MECHANISMS CREATE THE BASIS FOR THE DIVERSE HEALTH OUTCOMES CAUSED BY AIR POLLUTION. OXIDATIVE STRESS AND A SUBCLINICAL INFLAMMATORY RESPONSE IN THE LUNGS AND ON A SYSTEMIC LEVEL ("LOW-GRADE SYSTEMIC INFLAMMATION") ARE CONSIDERED TO BE KEY MECHANISMS. THEY PROMOTE SECONDARY ALTERATIONS IN THE BODY, SUCH AS VASCULAR OR METABOLIC PROCESSES, AND MAY ALSO RESULT IN THE CURRENTLY STUDIED EPIGENETIC PHENOMENA OR NEUROINFLAMMATION. IN THIS CONTEXT, THE HEALTH SIGNIFICANCE OF SOLUBLE PARTICULATE MATTER AND THE ROLE OF ULTRAFINE PARTICLES TRANSLOCATED ACROSS BIOLOGICAL MEMBRANES INTO BLOOD VESSEL AND TRANSPORTED VIA THE CIRCULATION TO SECONDARY TARGET ORGANS, SUCH AS LIVER, BRAIN OR THE FETUS, ARE INTENSIVELY DISCUSSED.DIABETES IS ONE OF THE LEADING CHRONIC DISEASES WORLDWIDE, WITH A PREVALENCE OF ALMOST 14 % IN GERMANY. ALTHOUGH LIFESTYLE FACTORS ARE THE MAIN CAUSES, CURRENT EVIDENCE SUGGESTS THAT LONG-TERM EXPOSURE TO AIR POLLUTION MAY ADDITIONALLY INCREASE THE RISK FOR TYPE 2 DIABETES. SUPPORTING EVIDENCE FOR A CAUSAL ROLE OF AIR POLLUTION IS PROVIDED BY STUDIES ADDRESSING THE REGULATION OF THE BLOOD GLUCOSE LEVELS IN METABOLICALLY HEALTHY PARTICIPANTS, INSULIN SENSITIVITY, OR PREGNANCY-RELATED DIABETES. EXPERIMENTAL STUDIES PROVIDE FURTHER SUPPORT FOR PLAUSIBLE BIOLOGICAL MECHANISMS. HOWEVER, PROSPECTIVE STUDIES ARE NEEDED TO GAIN MORE EVIDENCE, TAKING MULTIPLE LIFESTYLE AND ENVIRONMENTAL FACTORS, SUCH AS GREEN SPACE AND NOISE, AND AN IMPROVED INDIVIDUAL EXPOSURE ASSESSMENT INTO ACCOUNT.THE AGING POPULATION HAS AN INCREASED RISK OF NEURODEGENERATIVE DISEASES. FIRST STUDIES POINT TOWARDS A CONTRIBUTION OF CHRONIC EXPOSURE TO AIR POLLUTION, SPECIFICALLY BY PARTICULATE MATTER. SEVERAL STUDIES REPORT ITS ASSOCIATION WITH DECREASED NEUROCOGNITIVE CAPACITY OR AN INCREASED PREVALENCE OF DEMENTIA OR ALZHEIMER'S DISEASE IN ADULTS. HOWEVER, THE STUDIES ARE INHOMOGENEOUS REGARDING DESIGN, EXPOSURE AND OUTCOME, LEADING TO INCONSISTENT RESULTS. WITH RESPECT TO THE INFLUENCE ON NEUROCOGNITIVE DEVELOPMENT OF CHILDREN, FIRST STUDIES SUGGEST AN ASSOCIATION BETWEEN THE LEVEL OF AIR POLLUTION, E. G. AT SCHOOL, AND DELAYED COGNITIVE DEVELOPMENT.EVEN THOUGH THE EVIDENCE FOR THE DIFFERENT BIOLOGICAL ENDPOINTS DURING PREGNANCY IS STILL HETEROGENEOUS, THE STUDIES GENERALLY POINT TOWARDS AN ADVERSE IMPACT OF AIR POLLUTION ON THE MATERNAL AND FETAL ORGANISMS. THE STRONGEST EVIDENCE EXISTS FOR LOW BIRTH WEIGHT, WITH SMALL EFFECT SIZES OF ONLY SOME GRAMS, AND FOR A HIGHER INCIDENCE OF REDUCED BIRTH WEIGHT (< 2500 G). AN INCREASED RISK FOR GESTATIONAL HYPERTENSION AND PREECLAMPSIA UNDERSCORES THE POSSIBLE IMPACT OF EXPOSURE TO AIR POLLUTION ON THE MATERNAL ORGANISM. HOWEVER, THE CURRENT BODY OF EVIDENCE DOES NOT YET ALLOW A FINAL CONCLUSION ON THE INFLUENCE OF INTRAUTERINE EXPOSURE TO AIR POLLUTION REGARDING EARLY CHILDHOOD LUNG FUNCTION AND DEVELOPMENT OF ALLERGIES, PARTICULARLY IN LIGHT OF THE FACT THAT IT IS HARD TO DISTINGUISH IN EPIDEMIOLOGICAL STUDIES BETWEEN THE EFFECTS OF PRE- AND POSTNATAL EXPOSURE. 2019 19 5156 42 PRE-BIRTH ORIGINS OF ALLERGY AND ASTHMA. ALLERGY IS A CHRONIC DISEASE THAT CAN DEVELOP AS EARLY AS INFANCY, SUGGESTING THAT EARLY LIFE FACTORS ARE IMPORTANT IN ITS AETIOLOGY. VARIABLE ASSOCIATIONS BETWEEN SIZE AT BIRTH, A CRUDE MARKER OF THE FETAL ENVIRONMENT, AND ALLERGY HAVE BEEN REPORTED IN HUMANS AND REQUIRE COMPREHENSIVE REVIEW. ASSOCIATIONS BETWEEN BIRTH WEIGHT AND ALLERGY ARE HOWEVER CONFOUNDED IN HUMANS, AND WE AND OTHERS HAVE THEREFORE BEGUN EXPLORING THE EFFECTS OF EARLY LIFE EVENTS ON ALLERGY IN EXPERIMENTAL MODELS. IN PARTICULAR, WE ARE USING OVINE MODELS TO INVESTIGATE WHETHER AND HOW A RESTRICTED ENVIRONMENT BEFORE BIRTH PROTECTS AGAINST ALLERGY, WHETHER METHYL DONOR AVAILABILITY CONTRIBUTES TO ALLERGIC PROTECTION IN IUGR, AND WHY MATERNAL ASTHMA DURING PREGNANCY IS ASSOCIATED WITH INCREASED RISKS OF ALLERGIC DISEASE IN CHILDREN. WE FOUND THAT EXPERIMENTAL INTRAUTERINE GROWTH RESTRICTION (IUGR) IN SHEEP REDUCED CUTANEOUS RESPONSES TO ANTIGENS IN PROGENY, DESPITE NORMAL OR ELEVATED IGE RESPONSES. FURTHERMORE, MATERNAL METHYL DONOR SUPPLEMENTATION IN LATE PREGNANCY PARTIALLY REVERSED EFFECTS OF EXPERIMENTAL IUGR, CONSISTENT WITH THE PROPOSAL THAT EPIGENETIC PATHWAYS UNDERLIE SOME BUT NOT ALL EFFECTS OF IUGR ON ALLERGIC SUSCEPTIBILITY. OVINE EXPERIMENTAL ALLERGIC ASTHMA WITH EXACERBATIONS REDUCES RELATIVE FETAL SIZE IN LATE GESTATION, WITH SOME CHANGES IN IMMUNE POPULATIONS IN FETAL THYMUS SUGGESTIVE OF INCREASED ACTIVATION. MATERNAL ALLERGIC ASTHMA IN MICE ALSO PREDISPOSES PROGENY TO ALLERGY DEVELOPMENT. IN CONCLUSION, THESE FINDINGS IN EXPERIMENTAL MODELS PROVIDE DIRECT EVIDENCE THAT A PERTURBED ENVIRONMENT BEFORE BIRTH ALTERS IMMUNE SYSTEM DEVELOPMENT AND POSTNATAL FUNCTION, AND PROVIDE OPPORTUNITIES TO INVESTIGATE UNDERLYING MECHANISMS AND DEVELOP AND EVALUATE INTERVENTIONS. 2017 20 2159 29 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