1 6361 174 THE ROLE OF INNATE IMMUNITY IN THE PATHOGENESIS OF PRENEOPLASIA IN DRUG-INDUCED CHRONIC HEPATITIS BASED ON A MOUSE MODEL. INNATE IMMUNITY FACTORS SUCH AS CONVERSION OF THE 26S PROTEASOME TO FORM THE IMMUNOPROTEASOME AND THE TOLL-LIKE RECEPTOR SIGNALING PATHWAYS ARE ACTIVATED IN CHRONIC HEPATITIS INDUCED BY THE CARCINOGENIC DRUG DDC. OVER TIME, PRENEOPLASTIC HEPATOCYTE PHENOTYPES APPEAR IN THE LIVER PARENCHYMA. THESE CHANGED HEPATOCYTES EXPAND IN NUMBER BECAUSE THEY HAVE A GROWTH ADVANTAGE OVER NORMAL HEPATOCYTES WHEN RESPONDING TO CHRONIC LIVER INJURY. THE CHANGED HEPATOCYTES CAN BE IDENTIFIED USING IMMUNOFLUORESCENT ANTIBODIES TO PRENEOPLASTIC CELLS E.G. FAT10/UBD, A2 MACROGLOBULIN, GLUTATHIONE TRANSPEPTIDASE, ALPHA FETOPROTEIN, GLYCIPAN 3, FAS, AND GAMMA GLUTAMYL TRANSPEPTIDASE. THE FORMATION OF THE PRENEOPLASTIC CELLS OCCURS CONCOMITANT WITH ACTIVATION OF THE TOLL-LIKE RECEPTOR SIGNALING PATHWAYS AND THE TRANSFORMATION OF THE 26S PROTEASOME TO FORM THE IMMUNOPROTEASOME. THIS TRANSFORMATION IS IN RESPONSE TO INTERFERON STIMULATING RESPONSE ELEMENT ON THE PROMOTER OF THE FAT10/UBD GENE. NFKAPPAB, ERK, P38 AND JNK ARE ALSO UP REGULATED. SPECIFIC INHIBITORS BLOCK THESE RESPONSES IN VITRO IN A MOUSE TUMOR CELL LINE EXPOSED TO INTERFERON GAMMA. MALLORY-DENK BODIES FORM IN THESE PRENEOPLASTIC CELLS, BECAUSE OF THE DEPLETION OF THE 26S PROTEASOME DUE TO FORMATION OF THE IMMUNOPROTEASOME. THUS, MDB FORMING CELLS ARE ALSO MARKERS OF THE PRENEOPLASTIC HEPATOCYTES. THE UBD POSITIVE PRENEOPLASTIC CELLS REGRESS WHEN THE LIVER INJURY INDUCED CHRONIC HEPATITIS SUBSIDES. WHEN THE DRUG DDC IS REFED TO MICE AND CHRONIC HEPATITIS IS ACTIVATED, THE PRENEOPLASTIC CELL POPULATION EXPANDS AND MALLORY-DENK BODIES RAPIDLY REFORM. THIS RESPONSE IS REMEMBERED BY THE PRENEOPLASTIC CELLS FOR AT LEAST FOUR MONTHS INDICATING THAT AN EPIGENETIC CELLULAR MEMORY HAS FORMED IN THE PRENEOPLASTIC CELLS. THIS PROLIFERATIVE RESPONSE IS PREVENTED BY FEEDING METHYL DONORS SUCH AS S-ADENOSYLMETHIONINE OR BETAINE. DRUG FEEDING REDUCES THE METHYLATION OF H(3) K4, 9, AND 27 AND THIS RESPONSE IS PREVENTED BY FEEDING THE METHYL DONORS. AFTER 8 TO 15MONTHS OF DRUG WITHDRAWAL IN MICE THE PRENEOPLASTIC LIVER CELLS PERSIST AS SINGLE OR SMALL CLUSTERS OF CELLS IN THE LIVER LOBULES. MULTIPLE LIVER TUMORS FORM, SOME OF WHICH ARE HEPATOCELLULAR CARCINOMAS. THE TUMORS IMMUNOSTAIN POSITIVELY FOR THE SAME PRENEOPLASTIC MARKERS AS THE PRENEOPLASTIC CELLS. SIMILAR CELLS ARE IDENTIFIED IN HUMAN CIRRHOSIS AND HEPATOCELLULAR CARCINOMA INDICATING THE RELEVANCE OF THE DRUG MODEL DESCRIBED HERE TO THE PRENEOPLASTIC CHANGES ASSOCIATED WITH HUMAN CHRONIC HEPATITIS AND HEPATOCELLULAR CARCINOMA. 2011 2 4886 29 OVERWEIGHT AND OBESITY BEFORE, DURING AND AFTER PREGNANCY: PART 1: PATHOPHYSIOLOGY, MOLECULAR BIOLOGY AND EPIGENETIC CONSEQUENCES. OVERWEIGHT AND OBESITY BEFORE CONCEPTION AS WELL AS EXCESSIVE WEIGHT GAIN DURING PREGNANCY ARE ASSOCIATED WITH ENDOCRINOLOGICAL CHANGES OF MOTHER AND FETUS. INSULIN RESISTANCE PHYSIOLOGICALLY INCREASES DURING PREGNANCY, ADDITIONAL OBESITY FURTHER INCREASES INSULIN RESISTANCE. IN COMBINATION WITH REDUCED INSULIN SECRETION THIS LEADS TO GESTATIONAL DIABETES WHICH MAY DEVELOP INTO TYPE-2-DIABETES. THE ADIPOSE TISSUE PRODUCES TNF-ALPHA, INTERLEUKINS AND LEPTIN AND UPREGULATES THESE ADIPOKINES. INSULIN RESISTANCE AND OBESITY INDUCE INFLAMMATORY PROCESSES AND VASCULAR DYSFUNCTION, WHICH EXPLAINS THE INCREASED RATE OF PREGNANCY-RELATED HYPERTENSION AND PRE-ECLAMPSIA IN OBESE PREGNANT WOMEN. BETWEEN 14 AND 28 GESTATIONAL WEEKS, THE FETAL ADIPOSE TISSUE IS GENERATED AND THE NUMBER OF FAT LOBULES IS DETERMINED. THEREAFTER, AN INCREASE IN ADIPOSE TISSUE IS ARRANGED BY AN ENLARGEMENT OF THE LOBULES (HYPERTROPHY), OR EVEN AN INCREASE IN THE NUMBER OF FAT CELLS (HYPERPLASIA). HUMAN AND ANIMAL STUDIES HAVE SHOWN THAT MATERNAL OBESITY "PROGRAMMES" THE OFFSPRING FOR FURTHER OBESITY AND CHRONIC DISEASE. PREGNANT WOMEN, MIDWIVES, PHYSICIANS AND HEALTH CARE POLITICIANS SHOULD BE BETTER INFORMED ABOUT PREVENTION, PATHOPHYSIOLOGICAL MECHANISMS, AND THE BURDEN FOR SOCIETY CAUSED BY OBESITY BEFORE, DURING AND AFTER PREGNANCY. 2014 3 2792 59 FAT10 IS AN EPIGENETIC MARKER FOR LIVER PRENEOPLASIA IN A DRUG-PRIMED MOUSE MODEL OF TUMORIGENESIS. THERE IS CLINICAL EVIDENCE THAT CHRONIC LIVER DISEASES IN WHICH MDBS (MALLORY DENK BODIES) FORM PROGRESS TO HEPATOCELLULAR CARCINOMA. THE PRESENT STUDY PROVIDES EVIDENCE THAT LINKS MDB FORMATION INDUCED BY CHRONIC DRUG INJURY, WITH PRENEOPLASIA AND LATER TO THE FORMATION OF TUMORS, WHICH DEVELOP LONG AFTER DRUG WITHDRAWAL. EVIDENCE INDICATED THAT THIS LINK WAS DUE TO AN EPIGENETIC CELLULAR MEMORY INDUCED BY CHRONIC DRUG INGESTION. MICROARRAY ANALYSIS SHOWED THAT THE EXPRESSIONS OF MANY MARKERS OF PRENEOPLASIA (UBD, ALPHA FETOPROTEIN, KLF6 AND GLUTATHIONE-S-TRANSFERASE MU2) WERE INCREASED TOGETHER WHEN THE DRUG DDC WAS REFED. THESE CHANGES WERE SUPPRESSED BY S-ADENOSYLMETHIONINE FEEDING, INDICATING THAT THE DRUG WAS AFFECTING DNA AND HISTONES METHYLATION IN AN EPIGENETIC MANNER. THE LINK BETWEEN MDB FORMATION AND NEOPLASIA FORMATION WAS LIKELY DUE TO THE OVER EXPRESSION OF UBD (ALSO CALLED FAT10), WHICH IS UP REGULATED IN 90% OF HUMAN HEPATOCELLULAR CARCINOMAS. IMMUNOHISTOCHEMICAL STAINING OF DRUG-PRIMED MOUSE LIVERS SHOWED THAT FAT10 POSITIVE LIVER CELLS PERSISTED UP TO 4 MONTHS AFTER DRUG WITHDRAWAL AND THEY WERE STILL FOUND IN THE LIVERS OF MICE, 14 MONTHS AFTER DRUG WITHDRAWAL. THE REFEEDING OF DDC INCREASED THE PERCENT OF FAT10 HEPATOCYTES. 2008 4 6310 59 THE REGULATION OF NON-CODING RNA EXPRESSION IN THE LIVER OF MICE FED DDC. MALLORY-DENK BODIES (MDBS) ARE FOUND IN THE LIVER OF PATIENTS WITH ALCOHOLIC AND CHRONIC NONALCOHOLIC LIVER DISEASE, AND HEPATOCELLULAR CARCINOMA (HCC). DIETHYL 1,4-DIHYDRO-2,4,6,-TRIMETHYL-3,5-PYRIDINEDICARBOXYLATE (DDC) IS USED AS A MODEL TO INDUCE THE FORMATION OF MDBS IN MOUSE LIVER. PREVIOUS STUDIES IN THIS LABORATORY SHOWED THAT DDC INDUCED EPIGENETIC MODIFICATIONS IN DNA AND HISTONES. THE COMBINATION OF THESE MODIFICATIONS CHANGES THE PHENOTYPE OF THE MDB FORMING HEPATOCYTES, AS INDICATED BY THE MARKER FAT10. THESE EPIGENETIC MODIFICATIONS ARE PARTIALLY PREVENTED BY ADDING TO THE DIET S-ADENOSYLMETHIONINE (SAME) OR BETAINE, BOTH METHYL DONORS. THE EXPRESSION OF THREE IMPRINTED NCRNA GENES WAS FOUND TO CHANGE IN MDB FORMING HEPATOCYTES, WHICH IS THE SUBJECT OF THIS REPORT. NCRNA EXPRESSION WAS QUANTITATED BY REAL-TIME PCR AND RNA FISH IN LIVER SECTIONS. MICROARRAY ANALYSIS SHOWED THAT THE EXPRESSION OF THREE NCRNAS WAS REGULATED BY DDC: UP REGULATION OF H19, ANTISENSE IGF2R (AIR), AND DOWN REGULATION OF GTL2 (ALSO CALLED MEG3). S-ADENOSYLMETHIONINE (SAME) FEEDING PREVENTED THESE CHANGES. BETAINE, ANOTHER METHYL GROUP DONOR, PREVENTED ONLY H19 AND AIR UP REGULATION INDUCED BY DDC, ON MICROARRAYS. THE RESULTS OF THE SAME AND BETAINE GROUPS WERE CONFIRMED BY REAL-TIME PCR, EXCEPT FOR AIR EXPRESSION. AFTER 1 MONTH OF DRUG WITHDRAWAL, THE EXPRESSION OF THE THREE NCRNAS TENDED TOWARD CONTROL LEVELS OF EXPRESSION. LIVER TUMORS THAT DEVELOPED ALSO SHOWED UP REGULATION OF H19 AND AIR. THE RNA FISH APPROACH SHOWED THAT THE MDB FORMING CELLS' PHENOTYPE CHANGED THE LEVEL OF EXPRESSION OF AIR, H19 AND GTL2, COMPARED TO THE SURROUNDING CELLS. FURTHERMORE, OVER EXPRESSION OF H19 AND AIR WAS DEMONSTRATED IN TUMORS FORMED IN MICE WITHDRAWN FOR 9 MONTHS. THE DYSREGULATION OF NCRNA IN MDB FORMING LIVER CELLS HAS BEEN OBSERVED FOR THE FIRST TIME IN DRUG-PRIMED MICE ASSOCIATED WITH LIVER PRENEOPLASTIC FOCI AND TUMORS. 2009 5 2801 24 FEMALE OBESITY: SHORT- AND LONG-TERM CONSEQUENCES ON THE OFFSPRING. THE WORLDWIDE PREVALENCE OF OBESITY HAS RISEN OVER THE PAST FEW DECADES AND WOMEN ARE CURRENTLY MORE LIKELY THAN EVER TO ENTER PREGNANCY OBESE. PRE-PREGNANCY OBESITY AND EXCESSIVE GESTATIONAL WEIGHT GAIN INCREASE MISCARRIAGE RATES AND OBSTETRIC AND NEONATAL COMPLICATIONS, WHICH RESULT IN A LOWER HEALTHY LIVE BIRTH RATE. IN ADDITION TO ITS NEGATIVE CONSEQUENCES FOR THE MOTHER, OBESITY HAS BEEN SHOWN TO BE AN IMPORTANT RISK FACTOR FOR CHRONIC ILLNESSES, SUCH AS CARDIOVASCULAR DISEASE, METABOLIC SYNDROME AND TYPE 2 DIABETES IN THE ADOLESCENCE AND ADULTHOOD OF THE OFFSPRING. MOREOVER, MATERNAL OBESITY CAUSES PSYCHOLOGICAL PROBLEMS, PHYSICAL DISABILITIES AND HIGHER HEALTHCARE COSTS. FETAL PROGRAMMING OF METABOLIC FUNCTION INDUCED BY OBESITY, THROUGH PHYSIOLOGICAL AND/OR EPIGENETIC MECHANISMS, MAY HAVE AN INTERGENERATIONAL EFFECT AND COULD, THUS, PERPETUATE OBESITY IN THE NEXT GENERATION. IN ORDER TO BREAK THIS VICIOUS CIRCLE AND AVOID SERIOUS SHORT- AND LONG-TERM NEGATIVE OUTCOMES FOR BOTH MOTHERS AND FETUSES, THE PREVENTION AND ADEQUATE MANAGEMENT OF OBESITY AND GESTATIONAL WEIGHT GAIN ARE ESSENTIAL. 2013 6 1373 28 DEVELOPMENTAL ORIGINS OF NONALCOHOLIC FATTY LIVER DISEASE. OBESE PREGNANT WOMEN MAY TRANSMIT THEIR METABOLIC PHENOTYPE TO OFFSPRING, LEADING TO A CYCLE OF OBESITY AND DIABETES OVER GENERATIONS. EARLY CHILDHOOD OBESITY PREDICTS NONALCOHOLIC FATTY LIVER DISEASE (NAFLD), THE MOST COMMON CHRONIC HUMAN LIVER DISEASE. THE FETUS MAY BE VULNERABLE TO STEATOSIS BECAUSE IMMATURE FETAL ADIPOSE DEPOTS ARE NOT AVAILABLE TO BUFFER THE EXCESS TRANSPLACENTAL LIPID DELIVERY IN MATERNAL OBESITY. IN ANIMAL MODELS, IN UTERO HIGH-FAT DIET EXPOSURE RESULTS IN AN INCREASE IN THE ACCUMULATION OF LIVER TRIGLYCERIDES IN OFFSPRING AND INCREASED HEPATIC OXIDATIVE STRESS AND APOPTOSIS, PERHAPS PRIMING THE LIVER FOR LATER DEVELOPMENT OF NAFLD. INNATE IMMUNE DYSFUNCTION AND NECROINFLAMMATORY CHANGES HAVE BEEN OBSERVED IN POSTNATAL OFFSPRING LIVER OF ANIMALS BORN TO HIGH-FAT-FED DAMS. POSTWEANING, LIVERS OF OFFSPRING EXPOSED TO MATERNAL HIGH-FAT FEEDING IN UTERO SHARE PATHOPHYSIOLOGIC FEATURES WITH HUMAN NAFLD, INCLUDING INCREASED DE NOVO LIPOGENESIS AND DECREASED FREE FATTY ACID OXIDATION. HUMAN STUDIES USING MAGNETIC RESONANCE IMAGING HAVE SHOWN THAT MATERNAL BMI PREDICTS INFANT INTRAHEPATOCELLULAR LIPID STORAGE, AS SEEN IN ANIMAL MODELS. THE GENERATIONAL TRANSFER OF NAFLD MAY OCCUR VIA EPIGENETIC CHANGES IN OFFSPRING LIVER. TRANSMISSION OF MICROBIOTA FROM MOTHER TO INFANT MAY IMPACT ENERGY RETENTION AND IMMUNE FUNCTION THAT CONTRIBUTE TO A PREDISPOSITION TO NAFLD. 2014 7 1098 20 COLLATERAL DAMAGE: MATERNAL OBESITY DURING PREGNANCY CONTINUES TO RISE. IMPORTANCE: THE PANDEMIC OF OBESITY DURING PREGNANCY NOW AFFLICTS 1 OUT OF EVERY 2 PREGNANT WOMEN IN THE UNITED STATES. EVEN THOUGH UNINTENDED PREGNANCY HAS DECREASED TO 45% OF ALL PREGNANCIES, 50% OF THOSE UNINTENDED PREGNANCIES OCCUR IN OBESE WOMEN. OBJECTIVE: THIS STUDY AIMS TO IDENTIFY WHY CURRENT LIFESTYLE INTERVENTIONS FOR OBESE PREGNANCY ARE NOT EFFECTIVE AND WHAT THE NEWER COMPLICATIONS ARE FOR OBESITY DURING PREGNANCY. EVIDENCE ACQUISITION: AVAILABLE LITERATURES ON CURRENT TREATMENTS FOR MATERNAL OBESITY WERE REVIEWED FOR EFFECTIVENESS. EMERGING MATERNAL AND INFANT COMPLICATIONS FROM OBESITY DURING PREGNANCY WERE EXAMINED FOR SIGNIFICANCE. RESULTS: LIMITATIONS IN SUCCESSFUL INTERVENTIONS FELL INTO 3 BASIC CATEGORIES TO INCLUDE THE FOLLOWING: (1) PRECONCEPTION WEIGHT LOSS; (2) BARIATRIC SURGERY BEFORE PREGNANCY; AND (3) PREVENTION OF EXCESSIVE GESTATIONAL WEIGHT GAIN DURING PREGNANCY. EMERGING SIGNIFICANT PHYSIOLOGICAL CHANGES FROM MATERNAL OBESITY IS COMPOSED OF INFLAMMATION (PLACENTA AND HUMAN MILK), METABOLISM (HORMONES, MICROBIOME, FATTY ACIDS), AND OFFSPRING OUTCOMES (BODY COMPOSITION, CONGENITAL MALFORMATIONS, CHRONIC KIDNEY DISEASE, ASTHMA, NEURODEVELOPMENT, AND BEHAVIOR). CONCLUSIONS AND RELEVANCE: ARE CURRENT PREPREGNANCY LIFESTYLE AND BEHAVIORAL INTERVENTIONS FEASIBLE TO PREVENT MATERNAL OBESITY COMPLICATIONS? EPIGENETIC AND METABOLOMIC RESEARCH WILL BE CRITICAL TO DETERMINE WHAT IS NEEDED TO BLUNT THE EFFECTS OF MATERNAL OBESITY AND TO DISCOVER SUCCESSFUL TREATMENT. 2020 8 140 24 ABERRANT DNA METHYLATION MEDIATES THE TRANSGENERATIONAL RISK OF METABOLIC AND CHRONIC DISEASE DUE TO MATERNAL OBESITY AND OVERNUTRITION. MATERNAL OBESITY IS A RAPIDLY EVOLVING UNIVERSAL EPIDEMIC LEADING TO ACUTE AND LONG-TERM MEDICAL AND OBSTETRIC HEALTH ISSUES, INCLUDING INCREASED MATERNAL RISKS OF GESTATIONAL DIABETES, HYPERTENSION AND PRE-ECLAMPSIA, AND THE FUTURE RISKS FOR OFFSPRING'S PREDISPOSITION TO METABOLIC DISEASES. EPIGENETIC MODIFICATION, IN PARTICULAR DNA METHYLATION, REPRESENTS A MECHANISM WHEREBY ENVIRONMENTAL EFFECTS IMPACT ON THE PHENOTYPIC EXPRESSION OF HUMAN DISEASE. MATERNAL OBESITY OR OVERNUTRITION CONTRIBUTES TO THE ALTERATIONS IN DNA METHYLATION DURING EARLY LIFE WHICH, THROUGH FETAL PROGRAMMING, CAN PREDISPOSE THE OFFSPRING TO MANY METABOLIC AND CHRONIC DISEASES, SUCH AS NON-ALCOHOLIC FATTY LIVER DISEASE, OBESITY, DIABETES, AND CHRONIC KIDNEY DISEASE. THIS REVIEW AIMS TO SUMMARIZE FINDINGS FROM HUMAN AND ANIMAL STUDIES, WHICH SUPPORT THE ROLE OF MATERNAL OBESITY IN FETAL PROGRAMING AND THE POTENTIAL BENEFIT OF ALTERING DNA METHYLATION TO LIMIT MATERNAL OBESITY RELATED DISEASE IN THE OFFSPRING. 2021 9 4202 21 METABOLIC SYNDROME IN CHILDREN BORN SMALL-FOR-GESTATIONAL AGE. BEING BORN SMALL-FOR-GESTATIONAL AGE AND A RAPID INCREASE IN WEIGHT DURING EARLY CHILDHOOD AND INFANCY HAS BEEN STRONGLY LINKED WITH CHRONIC DISEASES, INCLUDING METABOLIC SYNDROME, WHICH HAS BEEN RELATED TO INTRAUTERINE LIFE ENVIRONMENT AND LINKED TO EPIGENETIC FETAL PROGRAMMING. METABOLIC SYNDROME INCLUDES WAIST CIRCUMFERENCE >/= 90(TH) PERCENTILE FOR AGE, SEX AND RACE, HIGHER LEVELS OF BLOOD PRESSURE, TRIGLYCERIDES AND FASTING GLUCOSE, AND LOW LEVELS OF HDL-CHOLESTEROL. INSULIN RESISTANCE MAY BE PRESENT AS EARLY AS 1 YEAR OF AGE, AND OBESITY AND/OR TYPE 2 DIABETES ARE MORE PREVALENT IN THOSE BORN SGA THAN THOSE BORN AGA. THE PROGRAMMING OF ADAPTIVE RESPONSES IN CHILDREN BORN SGA INCLUDES AN ASSOCIATION WITH INCREASED BLOOD PRESSURE, CHANGES IN ENDOTHELIAL FUNCTION, ARTERIAL PROPERTIES AND CORONARY DISEASE. EARLY INTERVENTIONS SHOULD BE DIRECTED TO APPROPRIATE MATERNAL NUTRITION, BEFORE AND DURING PREGNANCY, PROMOTION OF BREAST FEEDING, AND PREVENTION OF RAPID WEIGHT GAIN DURING INFANCY, AND TO PROMOTE A HEALTHY LIFESTYLE. 2011 10 5179 35 PREGNANCY: AN UNDERUTILIZED WINDOW OF OPPORTUNITY TO IMPROVE LONG-TERM MATERNAL AND INFANT HEALTH-AN APPEAL FOR CONTINUOUS FAMILY CARE AND INTERDISCIPLINARY COMMUNICATION. PHYSIOLOGIC ADAPTATIONS DURING PREGNANCY UNMASK A WOMAN'S PREDISPOSITION TO DISEASES. COMPLICATIONS ARE INCREASINGLY PREDICTED BY FIRST-TRIMESTER ALGORITHMS, AMPLIFY A PRE-EXISTING MATERNAL PHENOTYPE AND ACCELERATE RISKS FOR CHRONIC DISEASES IN THE OFFSPRING UP TO ADULTHOOD (BARKER HYPOTHESIS). RECENT EVIDENCE SUGGESTS THAT VICE VERSA, PREGNANCY DISEASES ALSO INDICATE MATERNAL AND EVEN GRANDPARENT'S RISKS FOR CHRONIC DISEASES (REVERSE BARKER HYPOTHESIS). PUB-MED AND EMBASE WERE REVIEWED FOR MESH TERMS "FETAL PROGRAMMING" AND "PREGNANCY COMPLICATIONS COMBINED WITH MATERNAL DISEASE" UNTIL JANUARY 2017. STUDIES LINKING PREGNANCY COMPLICATIONS TO FUTURE CARDIOVASCULAR, METABOLIC, AND THROMBOTIC RISKS FOR MOTHER AND OFFSPRING WERE REVIEWED. WOMEN WITH A HISTORY OF MISCARRIAGE, FETAL GROWTH RESTRICTION, PREECLAMPSIA, PRETERM DELIVERY, OBESITY, EXCESSIVE GESTATIONAL WEIGHT GAIN, GESTATIONAL DIABETES, SUBFERTILITY, AND THROMBOPHILIA MORE FREQUENTLY DEMONSTRATE WITH ECHOCARDIOGRAPHIC ABNORMALITIES, HIGHER FASTING INSULIN, DEVIATING LIPIDS OR CLOTTING FACTORS AND SHOW DEFECTIVE ENDOTHELIAL FUNCTION. THROMBOPHILIA HINTS TO THROMBOTIC RISKS IN LATER LIFE. PREGNANCY ABNORMALITIES CORRELATE WITH FUTURE CARDIOVASCULAR AND METABOLIC COMPLICATIONS AND EARLIER MORTALITY. CONVERSELY, WOMEN WITH A NORMAL PREGNANCY HAVE LOWER RATES OF SUBSEQUENT DISEASES THAN THE GENERAL FEMALE POPULATION CREATING THE TERM: "PREGNANCY AS A WINDOW FOR FUTURE HEALTH." ALTHOUGH THE PLACENTA WORKS AS A GATEKEEPER, MANY PREGNANCY COMPLICATIONS MAY LEAD TO SICKNESS AND EARLIER DEATH IN LATER LIFE WHEN THE CHILD BECOMES AN ADULT. THE EPIGENETIC MECHANISMS AND THE MISMATCH BETWEEN PRE- AND POSTNATAL LIFE HAVE CREATED THE TERM "FETAL ORIGIN OF ADULT DISEASE." UP TO NOW, THE IMPACT OF CARDIOVASCULAR, METABOLIC, OR THROMBOTIC RISK PROFILES HAS BEEN INVESTIGATED SEPARATELY FOR MOTHER AND CHILD. IN THIS MANUSCRIPT, WE STRIVE TO ILLUSTRATE THE CONSEQUENCES FOR BOTH, FETUS AND MOTHER WITHIN A COHESIVE PERSPECTIVE AND THUS TRY TO DEMONSTRATE THE COMPLEX INTERRELATIONSHIP OF GENETICS AND EPIGENETICS FOR LONG-TERM HEALTH OF SOCIETIES AND FUTURE GENERATIONS. MATERNAL-FETAL MEDICINE SPECIALISTS SHOULD HAVE A KEY ROLE IN THE PREVENTION OF NON-COMMUNICABLE DISEASES BY IMPLEMENTING A FRAMEWORK FOR PATIENT CONSULTATION AND INTERDISCIPLINARY NETWORKS. HEALTH-CARE PROVIDERS AND POLICY MAKERS SHOULD INCREASINGLY INVEST IN A STRATIFIED PRIMARY PREVENTION AND FOLLOW-UP TO REDUCE THE INCREASING NUMBER OF MANIFEST CARDIOVASCULAR AND METABOLIC DISEASES AND TO PREVENT WASTE OF HEALTH-CARE RESOURCES. 2017 11 6867 26 [PARENTAL AGEING AND ASSISTED REPRODUCTION TECHNOLOGIES: ANALYSIS OF RISK OF CHRONIC DISEASES IN THE PROGENY]. CONCEPTION OF A CHILD AT ADVANCED PARENTAL AGE (> 35 YEARS) HAS BEEN STEADILY INCREASING IN RECENT DECADES, ESPECIALLY IN DEVELOPED COUNTRIES. SOCIO-ECONOMIC FACTORS, EFFECTIVE CONTRACEPTIVES, AND THE AVAILABILITY OF ASSISTED REPRODUCTION TECHNOLOGIES (ART) HAVE A DIRECT IMPACT ON POSTPONING THE DECISION TO HAVE A BABY. ART ENABLES REPRODUCTIVE SUCCESS FOR PEOPLE DIAGNOSED AS INFERTILE OR WITH REDUCED POSSIBILITIES OF BECOMING PREGNANT DUE TO CONCOMITANT PATHOLOGIES. EPIDEMIOLOGICAL STUDIES INDICATE THAT BOTH ADVANCED PARENTAL AGE AND ART ARE ASSOCIATED WITH PATHOLOGIES OF PREGNANCY, SUCH AS GESTATIONAL DIABETES, RISK OF PRE-ECLAMPSIA, MISCARRIAGE, PLACENTAL ABRUPTION, PRETERM LABOR, STILLBIRTH, NEURODEVELOPMENTAL DISORDERS AND CHRONIC DISEASE OF THE OFFSPRING. IN OUR WORK, WE WILL FOCUS ON THE AVAILABLE INFORMATION ON METABOLIC CHANGES THAT INCREASE THE RISK OF DEVELOPING CARDIOVASCULAR DISEASES IN THE OFFSPRING OF PARENTS AT AN ADVANCED AGE AND CONCEIVED THROUGH ART. FINALLY, WE WILL ADDRESS THE SOURCES OF THE OBSERVED DISTURBANCES AT THE GAMETE AND EMBRYO LEVEL, RELATED TO OXYGEN STRESS, EPIGENETIC MODIFICATIONS AND DNA DAMAGE, CONSIDERING POSSIBLE RESCUE ACTIONS. 2022 12 3578 25 IMPACT OF PARENTAL OVER- AND UNDERWEIGHT ON THE HEALTH OF OFFSPRING. PARENTAL EXCESS WEIGHT AND ESPECIALLY PREGESTATIONAL MATERNAL OBESITY AND EXCESSIVE WEIGHT GAIN DURING PREGNANCY HAVE BEEN RELATED TO AN INCREASED RISK OF METABOLIC (OBESITY, TYPE 2 DIABETES, CARDIOVASCULAR DISEASE, METABOLIC SYNDROME) AND NONMETABOLIC (CANCER, OSTEOPOROSIS, ASTHMA, NEUROLOGIC ALTERATIONS) DISEASES IN THE OFFSPRING, PROBABLY MEDIATED BY EPIGENETIC MECHANISMS OF FETAL PROGRAMMING. MATERNAL UNDERWEIGHT IS LESS COMMON IN DEVELOPED SOCIETIES, BUT THE DISCREPANCY BETWEEN A POOR NUTRITIONAL ENVIRONMENT IN UTERO AND A NORMAL OR EXCESSIVE POSTNATAL FOOD SUPPLY WITH RAPID GROWTH CATCH-UP APPEARS TO BE THE MAIN CANDIDATE MECHANISM OF THE DEVELOPMENT OF CHRONIC DISEASES DURING THE OFFSPRING'S ADULTHOOD. THE ROLE OF THE POSTNATAL ENVIRONMENT IN BOTH SCENARIOS (PARENTAL OVERWEIGHT OR UNDERWEIGHT) ALSO SEEMS TO INFLUENCE THE OFFSPRING'S HEALTH. LIFESTYLE INTERVENTIONS BEFORE AND DURING PREGNANCY IN BOTH PARENTS, BUT ESPECIALLY IN THE MOTHER, AS WELL AS IN CHILDREN AFTER BIRTH, ARE ADVISABLE TO COUNTERACT THE MANY UNDESIRABLE CHRONIC CONDITIONS DESCRIBED. 2019 13 5584 20 ROLE OF OBESITY IN FEMALE REPRODUCTION. CONTEMPORARY SCIENTISTS NEED NO "P VALUE" AND "RELATIVE RISK" STATISTICS TO BE EXQUISITELY AWARE OF THE INCREASING PREVALENCE OF OBESITY AND COMPLICATIONS POSED BY OBESITY. IT IS NOW WELL RECOGNIZED THAT OBESITY IS STRONGLY ASSOCIATED WITH TYPE 2 DIABETES, HYPERTENSION, VASCULAR DISEASE, TUMORS AND REPRODUCTIVE DISORDERS. OBESE WOMEN SHOW LOWER LEVELS OF GONADOTROPIN HORMONES, REDUCED FECUNDITY, HIGHER MISCARRIAGE RATES AND POORER OUTCOMES OF IN VITRO FERTILIZATION, REVEALING THAT OBESITY AFFECTS FEMALE REPRODUCTION. IN ADDITION, ADIPOSE TISSUE CONTAINS SPECIAL IMMUNE CELLS AND OBESITY-INDUCED INFLAMMATION IS A CHRONIC, LOW-GRADE INFLAMMATORY RESPONSE. HEREIN, WE MAINLY REVIEW DETRIMENTAL INFLUENCES OF OBESITY IN THE COMPLETE PROCESS OF FEMALE REPRODUCTION, INCLUDING HYPOTHALAMIC-PITUITARY-OVARIAN AXIS, OOCYTE MATURATION, EMBRYO AND FETAL DEVELOPMENT. IN THE LATTER PART, WE VIEW OBESITY-INDUCED INFLAMMATION AND DISCUSS RELATED EPIGENETIC IMPACT ON FEMALE REPRODUCTION. 2023 14 2805 28 FETAL MALNUTRITION AND LONG-TERM OUTCOMES. EPIDEMIOLOGICAL STUDIES HAVE SHOWN THAT LOWER BIRTHWEIGHT IS ASSOCIATED WITH A WIDE RANGE OF ADVERSE OUTCOMES IN LATER LIFE, INCLUDING POORER 'HUMAN CAPITAL' (SHORTER STATURE, LOWER COGNITIVE PERFORMANCE), INCREASED RISK FACTORS FOR LATER DISEASE (HIGHER BLOOD PRESSURE AND REDUCED GLUCOSE TOLERANCE, AND LUNG, KIDNEY AND IMMUNE FUNCTION), CLINICAL DISEASE (DIABETES, CORONARY HEART DISEASE, CHRONIC LUNG AND KIDNEY DISEASE), AND INCREASED ALL-CAUSE AND CARDIOVASCULAR MORTALITY. HIGHER BIRTHWEIGHT IS ASSOCIATED WITH AN INCREASED RISK OF CANCER AND (IF CAUSED BY GESTATIONAL DIABETES) OBESITY AND DIABETES. THE 'DEVELOPMENTAL ORIGINS OF HEALTH AND DISEASE' HYPOTHESIS PROPOSES THAT FETAL NUTRITION HAS PERMANENT EFFECTS ON GROWTH, STRUCTURE AND METABOLISM ('PROGRAMMING'). THIS IS SUPPORTED BY STUDIES IN ANIMALS SHOWING THAT MATERNAL UNDER- AND OVERNUTRITION DURING PREGNANCY CAN PRODUCE SIMILAR ABNORMALITIES IN THE ADULT OFFSPRING. COMMON CHRONIC DISEASES COULD POTENTIALLY BE PREVENTED BY ACHIEVING OPTIMAL FETAL NUTRITION, AND THIS COULD HAVE ADDITIONAL BENEFITS FOR SURVIVAL AND HUMAN CAPITAL. RECENT FOLLOW-UP OF CHILDREN BORN AFTER RANDOMIZED NUTRITIONAL INTERVENTIONS IN PREGNANCY PROVIDES WEAK EVIDENCE OF BENEFICIAL EFFECTS ON GROWTH, VASCULAR FUNCTION, LIPID CONCENTRATIONS, GLUCOSE TOLERANCE AND INSULIN RESISTANCE. ANIMAL STUDIES INDICATE THAT EPIGENETIC PHENOMENA MAY BE AN IMPORTANT MECHANISM UNDERLYING PROGRAMMING, AND THAT NUTRITIONAL INTERVENTIONS MAY NEED TO START PRECONCEPTIONALLY. 2013 15 4065 30 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 16 5057 29 PHENOBARBITAL MECHANISTIC DATA AND RISK ASSESSMENT: ENZYME INDUCTION, ENHANCED CELL PROLIFERATION, AND TUMOR PROMOTION. CHRONIC EXPOSURE TO HIGH DOSES OF PHENOBARBITAL (PB) CAUSES HEPATOCELLULAR ADENOMAS IN BOTH MICE AND RATS AND HEPATOCELLULAR CARCINOMAS IN SOME STRAINS OF MICE. LONG-TERM PB THERAPY HAS NOT BEEN FOUND TO CAUSE HUMAN TUMORS. PB IS NOT DNA REACTIVE, AND MOST GENOTOXICITY TESTS HAVE YIELDED NEGATIVE RESULTS. PB HAS BEEN EXTENSIVELY STUDIED AS AN EPIGENETIC, RODENT LIVER TUMOR PROMOTER. AT EXPOSURES CAUSING RODENT LIVER TUMORS, PB HAS MEASURABLE EFFECTS ON HEPATOCYTES: PB INHIBITS CELL-TO-CELL COMMUNICATION; PB INDUCES ENZYMES, INCLUDING P450 CYTOCHROMES; PB STIMULATES PROLIFERATION AND INHIBITS APOPTOSIS OF HEPATOCYTES IN NEOPLASTIC FOCI. THRESHOLD EXPOSURES FOR SOME OF THESE ENDPOINTS COINCIDE WITH THE THRESHOLD EXPOSURE FOR TUMORIGENESIS. 1996 17 3572 27 IMPACT OF MATERNAL DIABETES ON EPIGENETIC MODIFICATIONS LEADING TO DISEASES IN THE OFFSPRING. GESTATIONAL DIABETES, OCCURRING DURING THE HYPERGLYCEMIC PERIOD OF PREGNANCY IN MATERNAL LIFE, IS A PATHOLOGIC STATE THAT INCREASES THE INCIDENCE OF COMPLICATIONS IN BOTH MOTHER AND FETUS. OFFSPRING THUS EXPOSED TO AN ADVERSE FETAL AND EARLY POSTNATAL ENVIRONMENT MAY MANIFEST INCREASED SUSCEPTIBILITY TO A NUMBER OF CHRONIC DISEASES LATER IN LIFE. COMPELLING EVIDENCE FOR THE ROLE OF EPIGENETIC TRANSMISSION IN THESE COMPLICATIONS HAS COME FROM COMPARISON OF SIBLINGS BORN BEFORE AND AFTER THE DEVELOPMENT OF MATERNAL DIABETES, EXPOSURE TO THIS INTRAUTERINE DIABETIC ENVIRONMENT BEING SHOWN TO CAUSE ALTERATIONS IN FETAL GROWTH PATTERNS WHICH PREDISPOSE THESE INFANTS TO DEVELOPING OVERWEIGHT AND OBESITY LATER IN LIFE. DIABETES OF THE OFFSPRING IS ALSO MAINLY THE CONSEQUENCE OF EXPOSURE TO THE DIABETIC INTRAUTERINE ENVIRONMENT, IN ADDITION TO GENETIC SUSCEPTIBILITY. SINCE OBESITY AND DIABETES ARE KNOWN TO INCREASE THE RISK OF CARDIOVASCULAR DISEASE, CARDIOVASCULAR SEQUELAE IN THE OFFSPRING OF DIABETIC MOTHERS ARE VIRTUALLY INEVITABLE. RESEARCH DATA ALSO SUGGEST THAT EXPOSURE TO A DIABETIC INTRAUTERINE ENVIRONMENT DURING PREGNANCY IS ASSOCIATED WITH AN INCREASE IN DYSLIPIDEMIA, SUBCLINICAL VASCULAR INFLAMMATION, AND ENDOTHELIAL DYSFUNCTION PROCESSES IN THE OFFSPRING, ALL OF WHICH ARE LINKED WITH DEVELOPMENT OF CARDIOVASCULAR DISEASE LATER IN LIFE. THE MAIN UNDERLYING MECHANISMS INVOLVE PERSISTENT HYPERGLYCEMIA HYPERINSULINEMIA AND LEPTIN RESISTANCE. 2012 18 6724 24 VITAMIN D: EFFECTS ON PREGNANCY, MATERNAL, FETAL AND POSTNATAL OUTCOMES. A HIGH PREVALENCE OF VITAMIN D DEFICIENCY AND ITS NEGATIVE CONSEQUENCES FOR HEALTH IS IDENTIFIED AS AREA OF PRIMARY CONCERN FOR SCIENTISTS AND CLINICIANS WORLDWIDE. VITAMIN D DEFICIENCY AFFECTS NOT ONLY BONE HEALTH BUT MANY SOCIALLY SIGNIFICANT ACUTE AND CHRONIC DISEASES. OBSERVATIONAL STUDIES SUPPORT THAT PREGNANT AND LACTATING WOMEN, CHILDREN AND TEENAGERS REPRESENT THE HIGH RISK GROUPS FOR DEVELOPING VITAMIN D DEFICIENCY. CURRENT EVIDENCE HIGHLIGHTS A CRUCIAL ROLE OF VITAMIN D IN PROVIDING THE FETAL LIFE-SUPPORT SYSTEM AND FETUS DEVELOPMENT, INCLUDING IMPLANTATION, PLACENTAL FORMATION, INTRA- AND POSTPARTUM PERIODS. HYPOVITAMINOSIS D DURING PREGNANCY IS ASSOCIATED WITH A HIGHER INCIDENCE OF PLACENTAL INSUFFICIENCY, SPONTANEOUS ABORTIONS AND PRETERM BIRTH, PREECLAMPSIA, GESTATIONAL DIABETES, IMPAIRED FETAL AND CHILDHOOD GROWTH, INCREASED RISK OF AUTOIMMUNE DISEASES FOR OFFSPRINGS. POTENTIAL MECHANISMS FOR THE OBSERVED ASSOCIATIONS CONTAIN METABOLIC, IMMUNOMODULATORY AND ANTIINFLAMMATORY EFFECTS OF VITAMIN D. EPIGENETIC MODIFICATIONS IN VITAMIN D-ASSOCIATED GENES AND FETAL PROGRAMMING ARE OF PARTICULAR INTEREST. THE CONCEPT OF PREVENTING VITAMIN D DEFICIENCY IS ACTIVELY DISCUSSED, INCLUDING SUPPLEMENTATION IN DIFFERENT ETHNIC GROUPS, REQUIRED DOSES, TIME OF INITIATION AND THERAPY DURATION, INFLUENCE ON GESTATION AND CHILDBIRTH. AN ADEQUATE SUPPLY OF VITAMIN D DURING PREGNANCY IMPROVES THE MATERNAL AND FETAL OUTCOMES, SHORT AND LONG TERM HEALTH OF THE OFFSPRING. STILL CURRENT DATA ON RELATIONSHIP BETWEEN MATERNAL VITAMIN D STATUS AND PREGNANCY OUTCOMES REMAINS CONTROVERSIAL. THE LARGE OBSERVATIONAL AND INTERVENTIONAL RANDOMIZED CONTROL TRIALS ARE REQUIRED TO CREATE EVIDENCE-BASED GUIDELINES FOR THE SUPPLEMENTATION OF VITAMIN D IN PREGNANT AND LACTATING WOMEN. 2018 19 5693 28 SILENCING OF MATERNAL HEPATIC GLUCOCORTICOID RECEPTOR IS ESSENTIAL FOR NORMAL FETAL DEVELOPMENT IN MICE. EXCESSIVE OR CHRONIC STRESS CAN LEAD TO A VARIETY OF DISEASES DUE TO ABERRANT ACTIVATION OF THE GLUCOCORTICOID RECEPTOR (GR), A LIGAND ACTIVATED TRANSCRIPTION FACTOR. PREGNANCY REPRESENTS A PARTICULAR WINDOW OF SENSITIVITY IN WHICH EXCESSIVE STRESS CAN HAVE ADVERSE OUTCOMES, PARTICULARLY ON THE DEVELOPING FETUS. HERE WE SHOW MATERNAL HEPATIC STRESS HORMONE RESPONSIVENESS IS DIMINISHED VIA EPIGENETIC SILENCING OF THE GLUCOCORTICOID RECEPTOR DURING PREGNANCY. PROVOCATIVELY, REINSTALLATION OF GR TO HEPATOCYTES DURING PREGNANCY BY ADENO-ASSOCIATED VIRAL TRANSDUCTION DYSREGULATES GENES INVOLVED IN PROLIFERATION, RESULTING IN IMPAIRED PREGNANCY-INDUCED HEPATOMEGALY. DISRUPTION OF THE MATERNAL HEPATIC ADAPTATION TO PREGNANCY RESULTS IN IN UTERO GROWTH RESTRICTION (IUGR). THESE DATA DEMONSTRATE PREGNANCY ANTAGONIZES THE LIVER-SPECIFIC EFFECTS OF STRESS HORMONE SIGNALING IN THE MATERNAL COMPARTMENT TO ULTIMATELY SUPPORT THE HEALTHY DEVELOPMENT OF EMBRYOS. 2019 20 3934 56 LIVER TUMOR INDUCTION. THE SIGNIFICANCE OF THE DEVELOPMENT OF NODULAR LIVER LESIONS IN RODENTS FOLLOWING THE ADMINISTRATION OF TEST AGENTS RAISES SEVERAL QUESTIONS WHICH COULD BE PLACED IN ONE OF TWO GENERAL CATEGORIES: DIAGNOSTIC AND INTERPRETATIONAL. FROM A DIAGNOSTIC POINT OF VIEW, THE PROPER CLASSIFICATION OF LIVER TUMORS INTO A BENIGN AND MALIGNANT CATEGORY HAS TO BE BASED ON THE DIRECT CORRELATION BETWEEN THE MORPHOLOGY AND THE BIOLOGIC BEHAVIOR OF THE LESIONS. THEREFORE, EXTREME CARE SHOULD BE TAKEN TO SEPARATE THE MALIGNANT TUMORS FROM THE BENIGN AND THE BENIGN NEOPLASIA FROM THE HYPERPLASIA. THE SUBSTITUTION OF THE TERM "NEOPLASTIC NODULE" FOR HYPERPLASTIC NODULE IN RATS IS MISLEADING. MOST OF THESE NODULES, WHEN INDUCED UNDER SPECIAL EXPERIMENTAL CONDITIONS, MAY REGRESS OR REMODEL AND THUS THEY ARE NOT NEOPLASTIC IN NATURE. CHRONIC CARCINOGENICITY BIOASSAYS SHOULD INCLUDE "STOP" TYPE OF TREATMENT LEAVING ENOUGH OF THE OBSERVATIONAL TIME TO ESTABLISH THE FATE OF INDUCED NODULAR LESIONS. THE INDUCTION OF HISTOCHEMICALLY CHANGED FOCI CAN SERVE ONLY AS AN INDICATION OF POTENTIAL HEPATOCARCINOGENICITY AND SHOULD NOT BE EQUATED WITH THE INDUCTION OF BONA FIDE CANCER. THE BIOLOGIC INTERPRETATION OF NODULAR LIVER LESIONS, ESPECIALLY IN MICE, NEEDS FURTHER SCRUTINY BECAUSE THESE LESIONS HAVE A TENDENCY TO DEVELOP SPONTANEOUSLY WITH HIGH INCIDENCE IN SOME STRAINS. THIS CHARACTERISTIC THEN RAISES THE QUESTION AS TO THE MECHANISM BY WHICH VARIOUS AGENTS AUGMENT AND/OR ACCELERATE THE DEVELOPMENT OF SUCH TUMORS. IS THIS ACTION PRIMARILY PROMOTING OR INITIATING IN NATURE OR DOES IT REPRESENT THE INDUCTION OF TUMORS DE NOVO? THE ANSWER TO THIS DILEMMA MAY HAVE A DECISIVE BEARING ON CARCINOGENIC RISK ASSESSMENT AND THE TYPE OF REGULATORY ACTION, SINCE THE PROMOTING AGENTS POSSESS A THRESHOLD EFFECT AND THE PROMOTED CHANGES MAY REGRESS FOLLOWING WITHDRAWAL OF TREATMENT. THE INTERPRETATION OF HEPATOCARCINOGENESIS IS FURTHER COMPLICATED BY THE FACT THAT SEVERAL FACTORS, SUCH AS SEX HORMONAL ENVIRONMENT, INCREASED MITOTIC ACTIVITY FOLLOWING AN EXCESSIVE LOSS OF PARENCHYMAL CELLS, DEGREE OF CALORIC INTAKE, ENZYMATIC COMPLEMENT, AND ANIMALS' AGE AT THE TIME OF THE EXPOSURE TO A TEST AGENT, MAY INFLUENCE THE OUTCOME OF LIVER TUMOR DEVELOPMENT BY MODULATING "INITIATION" AND/OR "PROMOTION" OF CARCINOGENESIS. BROAD FLUCTUATION IN THE HISTORIC INCIDENCE OF LIVER TUMORS FURTHER COMPOUNDS THE COMPLEXITY OF THE PROPER BIOASSAY INTERPRETATION. THE SPECIFICALLY DESIGNED EXPERIMENTS MAY HAVE THE OBJECTIVE TO EXPLORE PREDOMINANTLY THE INITIATING OR PROMOTING EFFECTS OF THE AGENT. SUCH PROTOCOLS SHOULD BE USED WHENEVER NECESSARY TO DIFFERENTIATE BETWEEN THESE TWO MECHANISMS OF ACTION. IN THE CAUCASIANS, THE "SPONTANEOUS" DEVELOPMENT OF THE PRIMARY HEPATOCELLULAR TUMORS IS RARE. THE MAJORITY OF THESE TUMORS ARE MALIGNANT AND RAPIDLY FATAL. ACCORDING TO SOME HUMAN PATHOLOGISTS, THE BENIGN VARIETY OF LIVER TUMORS IS RARE AND IT DOES NOT REPRESENT NECESSARILY A PREMALIGNANT STAGE IN TUMOR DEVELOPMENT. CARCINOMA OF THE LIVER MAY OCCUR IN INFANCY, ESPECIALLY IN MALES BEFORE THE AGE OF 2 YEARS. THIS SUGGESTS A GENETIC CAUSATION OR CARCINOGENIC EXPOSURE IN UTERO. ONE OF THE GEOGRAPHIC FACTORS WHICH SIGNIFICANTLY ENHANCES THE INCIDENCE OF HEPATOCELLULAR CARCINOMA IN HUMANS IS EXPOSURE TO AFLATOXIN B(1) WHICH IS APPARENTLY POTENTIATED BY CONCURRENT LIVER CIRRHOSIS. BECAUSE MANY MORE AGENTS HAVE BEEN FOUND TO BE HEPATOCARCINOGENIC IN MICE AND RATS THAN IN MEN, A QUESTION ARISES AS TO THE DIRECT RELEVANCE OF RODENT STUDIES TO HUMANS. A BALANCED ASSESSMENT OF THE CARCINOGENICITY OF THE AGENT COULD ONLY BE REACHED IN CONSIDERING BOTH THE PHARMACOKINETICS AND THE DEVELOPMENT OF MALIGNANT NEOPLASIA IN OTHER ORGANS. IN THE CASE OF POSITIVE CARCINOGENICITY ASSESSMENT, THE OUTCOME OF THE MUTAGENICITY BIOASSAYS CAN SUGGEST GENIC (GENOTOXIC) OR PARAGENIC (EPIGENETIC) MODE OF ACTION IN MAMMALIAN SYSTEMS. 1982