1 2755 146 EXPRESSION OF CLASS II HISTONE DEACETYLASES IN TWO MOUSE MODELS OF TEMPORAL LOBE EPILEPSY. EPIGENETIC MECHANISMS LIKE ALTERED HISTONE ACETYLATION MAY HAVE A CRUCIAL ROLE IN EPILEPTOGENESIS. IN TWO MOUSE MODELS OF TEMPORAL LOBE EPILEPSY, WE INVESTIGATED CHANGES IN THE EXPRESSION OF CLASS II HISTONE DEACETYLASES (HDAC), A GROUP OF SIGNAL TRANSDUCERS THAT SHUTTLE BETWEEN NUCLEUS AND CYTOPLASM. INTRAHIPPOCAMPAL INJECTION OF KAINIC ACID (KA) INDUCED A STATUS EPILEPTICUS, DEVELOPMENT OF SPONTANEOUS SEIZURES (AFTER 3 DAYS), AND FINALLY CHRONIC EPILEPSY AND GRANULE CELL DISPERSION. EXPRESSION OF CLASS II HDAC MRNAS WAS INVESTIGATED AT DIFFERENT TIME INTERVALS AFTER KA INJECTION IN THE GRANULE CELL LAYERS AND IN SECTORS CA1 AND CA3 CONTRALATERAL TO THE SITE OF KA INJECTION LACKING NEURODEGENERATION. INCREASED EXPRESSION OF HDAC5 AND 9 MRNAS COINCIDED WITH PRONOUNCED GRANULE CELL DISPERSION IN THE KA-INJECTED HIPPOCAMPUS AT LATE INTERVALS (14-28 DAYS AFTER KA) AND EQUALLY AFFECTED BOTH HDAC9 SPLICE VARIANTS. IN CONTRAST, IN THE PILOCARPINE MODEL (SHOWING NO GRANULE CELL DISPERSION), WE OBSERVED DECREASES IN THE EXPRESSION OF HDAC5 AND 9 AT THE SAME TIME INTERVALS. BEYOND THIS, STRIKING SIMILARITIES BETWEEN BOTH TEMPORAL LOBE EPILEPSY MODELS SUCH AS FAST DECREASES IN HDAC7 AND 10 MRNAS DURING THE ACUTE STATUS EPILEPTICUS WERE OBSERVED, NOTABLY ALSO IN THE CONTRALATERAL HIPPOCAMPUS NOT AFFECTED BY NEURODEGENERATION. THE PARTICULAR PATTERNS OF HDAC MRNA EXPRESSION SUGGEST A ROLE IN EPILEPTOGENESIS AND GRANULE CELL DISPERSION. REDUCED EXPRESSION OF HDACS MAY RESULT IN INCREASED EXPRESSION OF PRO- AND ANTICONVULSIVE PROTEINS. ON THE OTHER HAND, EXPORT OF HDACS FROM THE NUCLEUS INTO THE CYTOPLASM COULD ALLOW FOR DEACETYLATION OF CYTOPLASMATIC PROTEINS INVOLVED IN AXONAL AND DENDRITIC REMODELING, LIKE GRANULE CELL DISPERSION. HDAC 5 AND HDAC 9 EXPRESSION IS HIGHLY INCREASED IN GRANULE CELLS OF THE KA-INJECTED HIPPOCAMPUS AND PARALLELS GRANULE CELL DISPERSION. BOTH HDACS ARE THOUGHT TO BE TARGETED TO THE CYTOPLASM AND TO ACT THERE BY DEACETYLATING CYTOPLASMATIC (E.G. CYTOSCELETON-RELATED) PROTEINS. 2016 2 3647 39 INCREASED REELIN PROMOTER METHYLATION IS ASSOCIATED WITH GRANULE CELL DISPERSION IN HUMAN TEMPORAL LOBE EPILEPSY. MESIAL TEMPORAL SCLEROSIS (MTS) IS THE MOST COMMON LESION IN CHRONIC, INTRACTABLE TEMPORAL LOBE EPILEPSIES (TLE) AND CHARACTERIZED BY SEGMENTAL NEURONAL CELL LOSS IN MAJOR HIPPOCAMPAL SEGMENTS. ANOTHER HISTOPATHOLOGICAL HALLMARK INCLUDES GRANULE CELL DISPERSION (GCD), AN ARCHITECTURAL DISTURBANCE OF THE DENTATE GYRUS ENCOUNTERED IN APPROXIMATELY 50% OF PATIENTS WITH MESIAL TEMPORAL SCLEROSIS. REELIN, WHICH PLAYS A KEY ROLE DURING HIPPOCAMPAL DEVELOPMENT AND MAINTENANCE OF LAMINAR ORGANIZATION, IS SYNTHESIZED AND RELEASED BY CAJAL-RETZIUS CELLS OF THE DENTATE MOLECULAR LAYER, AND PREVIOUS STUDIES HAVE SHOWN THAT REELIN TRANSCRIPT LEVELS ARE DOWNREGULATED IN HUMAN TEMPORAL LOBE EPILEPSIES SPECIMENS. TO INVESTIGATE WHETHER EPIGENETIC SILENCING BY REELIN PROMOTER METHYLATION MAY BE AN UNDERLYING PATHOGENETIC MECHANISM OF GCD, DNA WAS HARVESTED FROM 3 MICRODISSECTED HIPPOCAMPAL SUBREGIONS (I.E. MOLECULAR AND GRANULE CELL LAYERS OF THE DENTATE GYRUS AND PRESUBICULUM) FROM 8 MTS SPECIMENS WITH GCD, 5 TLE SAMPLES WITHOUT GCD, AND 3 AUTOPSY CONTROLS. PROMOTER METHYLATION WAS ANALYZED AFTER BISULFITE TREATMENT, CLONING, AND DIRECT SEQUENCING; IMMUNOHISTOCHEMISTRY WAS PERFORMED TO IDENTIFY CAJAL-RETZIUS CELLS. REELIN PROMOTER METHYLATION WAS FOUND TO BE GREATER IN TLE SPECIMENS THAN IN CONTROLS; PROMOTER METHYLATION CORRELATED WITH GCD AMONG TLE SPECIMENS (P < 0.0002). NO OTHER CLINICAL OR HISTOPATHOLOGICAL PARAMETER (I.E. SEX, AGE, SEIZURE DURATION, MEDICATION OR EXTENT, OF MTS) CORRELATED WITH PROMOTER METHYLATION. THESE DATA SUPPORT A COMPROMISED REELIN-SIGNALING PATHWAY AND IDENTIFY PROMOTER METHYLATION AS AN EPIGENETIC MECHANISM IN THE PATHOGENESIS OF TLE. 2009 3 935 34 CHRONIC LOW-DOSE EXPOSURE TO XENOESTROGEN AMBIENT AIR POLLUTANTS AND BREAST CANCER RISK: XENAIR PROTOCOL FOR A CASE-CONTROL STUDY NESTED WITHIN THE FRENCH E3N COHORT. BACKGROUND: BREAST CANCER IS THE MOST FREQUENT CANCER IN WOMEN IN INDUSTRIALIZED COUNTRIES. LIFESTYLE AND ENVIRONMENTAL FACTORS, PARTICULARLY ENDOCRINE-DISRUPTING POLLUTANTS, HAVE BEEN SUGGESTED TO PLAY A ROLE IN BREAST CANCER RISK. CURRENT EPIDEMIOLOGICAL STUDIES, ALTHOUGH NOT FULLY CONSISTENT, SUGGEST A POSITIVE ASSOCIATION OF BREAST CANCER RISK WITH EXPOSURE TO SEVERAL INTERNATIONAL AGENCY FOR RESEARCH ON CANCER GROUP 1 AIR-POLLUTANT CARCINOGENS, SUCH AS PARTICULATE MATTER, POLYCHLORINATED BIPHENYLS (PCB), DIOXINS, BENZO[A]PYRENE (BAP), AND CADMIUM. HOWEVER, EPIDEMIOLOGICAL STUDIES REMAIN SCARCE AND INCONSISTENT. IT HAS BEEN PROPOSED THAT THE MENOPAUSAL STATUS COULD MODIFY THE RELATIONSHIP BETWEEN POLLUTANTS AND BREAST CANCER AND THAT THE ASSOCIATION VARIES WITH HORMONE RECEPTOR STATUS. OBJECTIVE: THE XENAIR PROJECT WILL INVESTIGATE THE ASSOCIATION OF BREAST CANCER RISK (OVERALL AND BY HORMONE RECEPTOR STATUS) WITH CHRONIC EXPOSURE TO SELECTED AIR POLLUTANTS, INCLUDING PARTICULATE MATTER, NITROGEN DIOXIDE (NO2), OZONE (O3), BAP, DIOXINS, PCB-153, AND CADMIUM. METHODS: OUR RESEARCH IS BASED ON A CASE-CONTROL STUDY NESTED WITHIN THE FRENCH NATIONAL E3N COHORT OF 5222 INVASIVE BREAST CANCER CASES IDENTIFIED DURING FOLLOW-UP FROM 1990 TO 2011, AND 5222 MATCHED CONTROLS. A QUESTIONNAIRE WAS SENT TO ALL PARTICIPANTS TO COLLECT THEIR LIFETIME RESIDENTIAL ADDRESSES AND INFORMATION ON INDOOR POLLUTION. WE WILL ASSESS THESE EXPOSURES USING COMPLEMENTARY MODELS OF LAND-USE REGRESSION, ATMOSPHERIC DISPERSION, AND REGIONAL CHEMISTRY-TRANSPORT (CHIMERE) MODELS, VIA A GEOGRAPHIC INFORMATION SYSTEM. ASSOCIATIONS WITH BREAST CANCER RISK WILL BE MODELED USING CONDITIONAL LOGISTIC REGRESSION MODELS. WE WILL ALSO STUDY THE IMPACT OF EXPOSURE ON DNA METHYLATION AND INTERACTIONS WITH GENETIC POLYMORPHISMS. APPROPRIATE STATISTICAL METHODS, INCLUDING BAYESIAN MODELING, PRINCIPAL COMPONENT ANALYSIS, AND CLUSTER ANALYSIS, WILL BE USED TO ASSESS THE IMPACT OF MULTIPOLLUTANT EXPOSURE. THE FRACTION OF BREAST CANCER CASES ATTRIBUTABLE TO AIR POLLUTION WILL BE ESTIMATED. RESULTS: THE XENAIR PROJECT WILL CONTRIBUTE TO CURRENT KNOWLEDGE ON THE HEALTH EFFECTS OF AIR POLLUTION AND IDENTIFY AND UNDERSTAND ENVIRONMENTAL MODIFIABLE RISK FACTORS RELATED TO BREAST CANCER RISK. CONCLUSIONS: THE RESULTS WILL PROVIDE RELEVANT EVIDENCE TO GOVERNMENTS AND POLICY-MAKERS TO IMPROVE EFFECTIVE PUBLIC HEALTH PREVENTION STRATEGIES ON AIR POLLUTION. THE XENAIR DATASET CAN BE USED IN FUTURE EFFORTS TO STUDY THE EFFECTS OF EXPOSURE TO AIR POLLUTION ASSOCIATED WITH OTHER CHRONIC CONDITIONS. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): DERR1-10.2196/15167. 2020 4 1918 44 ENVIRONMENTAL CARCINOGENESIS AND TRANSGENERATIONAL TRANSMISSION OF CARCINOGENIC RISK: FROM GENETICS TO EPIGENETICS. THE DOMINANT PATHOGENIC MODEL, SOMATIC MUTATION THEORY (SMT), CONSIDERS CARCINOGENESIS AS A 'GENETIC ACCIDENT' DUE TO THE ACCUMULATION OF 'STOCHASTIC' DNA MUTATIONS. THIS MODEL WAS PROPOSED AND ACCEPTED BY THE SCIENTIFIC COMMUNITY WHEN CANCER MAINLY AFFECTED THE ELDERLY, BUT IT DOES NOT EXPLAIN THE EPIDEMIOLOGICAL OBSERVATION OF THE CONTINUOUS INCREASE IN CANCER INCIDENCE AMONG CHILDREN AND YOUNG ADULTS. SOMATIC MUTATION THEORY HAS BEEN PROPOSED FOR A REVISION BASED ON THE EMERGING EXPERIMENTAL EVIDENCE, AS IT DOES NOT FULLY ADDRESS SOME ISSUES THAT HAVE PROVEN TO BE CRUCIAL FOR CARCINOGENESIS, NAMELY: THE INFLAMMATORY CONTEXT OF CANCER; THE KEY ROLE PLAYED BY THE STROMA, MICROENVIRONMENT, ENDOTHELIAL CELLS, ACTIVATED MACROPHAGES, AND SURROUNDING TISSUES; AND THE DISTORTED DEVELOPMENTAL COURSE FOLLOWED BY THE NEOPLASTIC TISSUE. FURTHERMORE, SMT IS OFTEN NOT ABLE TO CONSIDER EITHER THE EXISTENCE OF SPECIFIC MUTATIONS RESULTING IN A WELL-DEFINED CANCER TYPE, OR A CLEAR RELATIONSHIP BETWEEN MUTATIONS AND TUMOR PROGRESSION. MOREOVER, IT DOES NOT EXPLAIN THE MECHANISM OF ACTION OF THE NON-MUTAGENIC AND ENVIRONMENTAL CARCINOGENS. IN THE LAST DECADE, CANCER RESEARCH HAS HIGHLIGHTED THE PROMINENT ROLE OF AN ALTERED REGULATION OF GENE EXPRESSION, SUGGESTING THAT CANCER SHOULD BE CONSIDERED AS A RESULT OF A POLYCLONAL EPIGENETIC DISRUPTION OF STEM/PROGENITOR CELLS, MEDIATED BY TUMOUR-INDUCING GENES. THE MATERNAL AND FETAL EXPOSURE TO A WIDE RANGE OF CHEMICALS AND ENVIRONMENTAL CONTAMINANTS IS RAISING THE ATTENTION OF THE SCIENTIFIC COMMUNITY. INDEED, THE MOST POWERFUL PROCARCINOGENIC MECHANISMS OF ENDOCRINE DISRUPTORS AND OTHER POLLUTANTS IS LINKED TO THEIR POTENTIAL TO INTERFERE EPIGENETICALLY WITH THE EMBRYO-FETAL PROGRAMMING OF TISSUES AND ORGANS, ALTERING THE REGULATION OF THE GENES INVOLVED IN THE CELL CYCLE, CELL PROLIFERATION, APOPTOSIS, AND OTHER KEY SIGNALING PATHWAYS. THE EMBRYO-FETAL EXPOSURE TO ENVIRONMENTAL, STRESSFUL, AND PROINFLAMMATORY TRIGGERS (FIRST HIT), SEEMS TO ACT AS A 'DISEASE PRIMER', MAKING FETAL CELLS AND TISSUES MORE SUSCEPTIBLE TO THE SUBSEQUENT ENVIRONMENTAL EXPOSURES (SECOND HIT), TRIGGERING THE CARCINOGENIC PATHWAYS. FURTHERMORE, EVEN AT THE MOLECULAR LEVEL, IN CARCINOGENESIS, 'EPIGENETICS PRECEDES GENETICS' AS GLOBAL DNA HYPOMETHYLATION, AND THE HYPERMETHYLATION OF TUMOR SUPPRESSOR GENES ARE COMMON BOTH IN CANCEROUS AND IN PRECANCEROUS CELLS, AND GENERALLY PRECEDE MUTATIONS. THESE EPIGENETIC MODELS MAY BETTER EXPLAIN THE INCREASE OF CANCER AND CHRONIC/DEGENERATIVE DISEASES IN THE LAST DECADES AND COULD BE USEFUL TO ADOPT APPROPRIATE PRIMARY PREVENTION MEASURES, ESSENTIALLY BASED ON THE REDUCTION OF MATERNAL-FETAL AND CHILD EXPOSURE TO SEVERAL PROCARCINOGENIC AGENTS AND FACTORS DISPERSED IN THE ENVIRONMENT AND IN THE FOOD-CHAINS, AS RECENTLY SUGGESTED BY THE WORLD HEALTH ORGANIZATION. 2018 5 5345 77 RAPID CHANGES IN EXPRESSION OF CLASS I AND IV HISTONE DEACETYLASES DURING EPILEPTOGENESIS IN MOUSE MODELS OF TEMPORAL LOBE EPILEPSY. A PROMINENT ROLE OF EPIGENETIC MECHANISMS IN MANIFESTATION OF EPILEPSY HAS BEEN PROPOSED. THUS ALTERED HISTONE H3 AND H4 ACETYLATION HAS BEEN DEMONSTRATED IN EXPERIMENTAL MODELS OF TEMPORAL LOBE EPILEPSY (TLE). WE NOW INVESTIGATED CHANGES IN THE EXPRESSION OF THE CLASS I AND CLASS IV HISTONE DEACETYLASES (HDAC) IN TWO COMPLEMENTARY MOUSE TLE MODELS. UNILATERAL INTRAHIPPOCAMPAL INJECTION OF KAINIC ACID (KA) INDUCED A STATUS EPILEPTICUS LASTING 6 TO 24H, DEVELOPMENT OF SPONTANEOUS LIMBIC SEIZURES (2 TO 3 DAYS AFTER KA INJECTION) AND CHRONIC EPILEPSY, AS REVEALED BY TELEMETRIC RECORDINGS OF THE EEGS. MICE WERE KILLED AT DIFFERENT INTERVALS AFTER KA INJECTION AND EXPRESSION OF HDAC MRNAS WAS INVESTIGATED BY IN SITU HYBRIDIZATION. WE OBSERVED MARKED DECREASES IN THE EXPRESSION OF HDACS 1, 2 AND 11 (BY UP TO 75%) IN THE GRANULE CELL AND PYRAMIDAL CELL LAYERS OF THE HIPPOCAMPUS DURING THE ACUTE STATUS EPILEPTICUS (2 TO 6H AFTER KA INJECTION). THIS WAS FOLLOWED BY INCREASED EXPRESSION OF ALL CLASS I HDAC MRNAS IN ALL PRINCIPAL CELL LAYERS OF THE HIPPOCAMPUS AFTER 12 TO 48 H. IN THE CHRONIC PHASE, 14 AND 28 DAYS AFTER KA, ONLY MODEST INCREASES IN THE EXPRESSION OF HDAC1 MRNA WERE OBSERVED IN GRANULE AND PYRAMIDAL CELLS. IMMUNOHISTOCHEMISTRY USING AN ANTIBODY DETECTING HDAC2 REVEALED RESULTS CONSISTENT WITH THE MRNA DATA AND INDICATES ALSO EXPRESSION IN GLIAL CELLS ON THE INJECTION SIDE. SIMILAR CHANGES AS SEEN IN THE KA MODEL WERE OBSERVED AFTER A PILOCARPINE-INDUCED STATUS EPILEPTICUS EXCEPT THAT DECREASES IN HDACS 2, 3 AND 8 WERE ALSO SEEN AT THE CHRONIC 28 DAY INTERVAL. THE PROMINENT DECREASES IN HDAC EXPRESSION DURING STATUS EPILEPTICUS ARE CONSISTENT WITH THE PREVIOUSLY DEMONSTRATED INCREASED EXPRESSION OF NUMEROUS PROTEINS AND WITH THE AUGMENTED ACETYLATION OF HISTONE H4. IT IS SUGGESTED THAT RESPECTIVE PUTATIVE GENE PRODUCTS COULD FACILITATE PROCONVULSIVE AS WELL AS ANTICONVULSIVE MECHANISMS. THE INCREASED EXPRESSION OF ALL CLASS I HDACS DURING THE "SILENT PHASE", ON THE OTHER HAND, MAY BE RELATED TO DECREASED HISTONE ACETYLATION, WHICH COULD CAUSE A DECREASE IN EXPRESSION OF CERTAIN PROTEINS, A MECHANISM THAT COULD ALSO PROMOTE EPILEPTOGENESIS. THUS, ADDRESSING HDAC EXPRESSION MAY HAVE A THERAPEUTIC POTENTIAL IN INTERFERING WITH A STATUS EPILEPTICUS AND WITH THE MANIFESTATION OF TLE. 2015 6 2772 43 EXTRACELLULAR ATP AND NEURODEGENERATION. ATP IS A POTENT SIGNALING MOLECULE ABUNDANTLY PRESENT IN THE CNS. IT ELICITS A WIDE ARRAY OF PHYSIOLOGICAL EFFECTS AND IS REGARDED AS THE PHYLOGENETICALLY MOST ANCIENT EPIGENETIC FACTOR PLAYING CRUCIAL BIOLOGICAL ROLES IN SEVERAL DIFFERENT TISSUES. THESE CAN RANGE FROM NEUROTRANSMISSION, SMOOTH MUSCLE CONTRACTION, CHEMOSENSORY SIGNALING, SECRETION AND VASODILATATION, TO MORE COMPLEX PHENOMENA SUCH AS IMMUNE RESPONSES, PAIN, MALE REPRODUCTION, FERTILIZATION AND EMBRYONIC DEVELOPMENT. ATP IS RELEASED INTO THE EXTRACELLULAR SPACE EITHER EXOCYTOTICALLY OR FROM DAMAGED AND DYING CELLS. IT IS OFTEN CO-RELEASED WITH OTHER NEUROTRANSMITTERS AND IT CAN INTERACT WITH GROWTH FACTORS AT BOTH RECEPTOR- AND/OR SIGNAL TRANSDUCTION-LEVEL. ONCE IN THE EXTRACELLULAR ENVIRONMENT, ATP BINDS TO SPECIFIC RECEPTORS TERMED P2. BASED ON PHARMACOLOGICAL PROFILES, ON SELECTIVITY OF COUPLING TO SECOND-MESSENGER PATHWAYS AND ON MOLECULAR CLONING, TWO MAIN SUBCLASSES WITH MULTIPLE SUBTYPES HAVE BEEN DISTINGUISHED. THEY ARE P2X, I.E. FAST CATION-SELECTIVE RECEPTOR CHANNELS (NA+, K+, CA2+), POSSESSING LOW AFFINITY FOR ATP AND RESPONSIBLE FOR FAST EXCITATORY NEUROTRANSMISSION, AND P2Y, I.E. SLOW G PROTEIN-COUPLED METABOTROPIC RECEPTORS, POSSESSING HIGHER AFFINITY FOR THE LIGAND. IN THE NERVOUS SYSTEM, THEY ARE BROADLY EXPRESSED IN BOTH NEURONS AND GLIAL CELLS AND CAN MEDIATE DUAL EFFECTS: SHORT-TERM SUCH AS NEUROTRANSMISSION, AND LONG-TERM SUCH AS TROPHIC ACTIONS. SINCE MASSIVE EXTRACELLULAR RELEASE OF ATP OFTEN OCCURS AFTER METABOLIC STRESS, BRAIN ISCHEMIA AND TRAUMA, PURINERGIC MECHANISMS ARE ALSO CORRELATED TO AND INVOLVED IN THE ETIOPATHOLOGY OF MANY NEURODEGENERATIVE CONDITIONS. FURTHERMORE, EXTRACELLULAR ATP PER SE IS TOXIC FOR PRIMARY NEURONAL DISSOCIATED AND ORGANOTYPIC CNS CULTURES FROM CORTEX, STRIATUM AND CEREBELLUM AND P2 RECEPTORS CAN MEDIATE AND AGGRAVATE HYPOXIC SIGNALING IN MANY CNS NEURONS. CONVERSELY, SEVERAL P2 RECEPTOR ANTAGONISTS ABOLISH THE CELL DEATH FATE OF PRIMARY NEURONAL CULTURES EXPOSED TO EXCESSIVE GLUTAMATE, SERUM/POTASSIUM DEPRIVATION, HYPOGLYCEMIA AND CHEMICAL HYPOXIA. IN PARALLEL WITH THESE DETRIMENTAL EFFECTS, ALSO TROPHIC FUNCTIONS HAVE BEEN EXTENSIVELY DESCRIBED FOR EXTRACELLULAR PURINES (BOTH FOR NEURONAL AND NON-NEURONAL CELLS), BUT THESE MIGHT EITHER AGGRAVATE OR AMELIORATE THE NORMAL CELLULAR CONDITIONS. IN SUMMARY, EXTRACELLULAR ATP PLAYS A VERY COMPLEX ROLE NOT ONLY IN THE REPAIR, REMODELING AND SURVIVAL OCCURRING IN THE NERVOUS SYSTEM, BUT EVEN IN CELL DEATH AND THIS CAN OCCUR EITHER AFTER NORMAL DEVELOPMENTAL CONDITIONS, AFTER INJURY, OR ACUTE AND CHRONIC DISEASES. 2003 7 502 33 ASSOCIATION OF ARSENIC EXPOSURE WITH WHOLE BLOOD DNA METHYLATION: AN EPIGENOME-WIDE STUDY OF BANGLADESHI ADULTS. BACKGROUND: ARSENIC EXPOSURE AFFECTS [FORMULA: SEE TEXT] PEOPLE WORLDWIDE, INCLUDING [FORMULA: SEE TEXT] IN BANGLADESH. ARSENIC EXPOSURE INCREASES THE RISK OF CANCER AND OTHER CHRONIC DISEASES, AND ONE POTENTIAL MECHANISM OF ARSENIC TOXICITY IS EPIGENETIC DYSREGULATION. OBJECTIVE: WE ASSESSED ASSOCIATIONS BETWEEN ARSENIC EXPOSURE AND GENOME-WIDE DNA METHYLATION MEASURED AT BASELINE AMONG 396 BANGLADESHI ADULTS PARTICIPATING IN THE HEALTH EFFECTS OF ARSENIC LONGITUDINAL STUDY (HEALS) WHO WERE EXPOSED BY DRINKING NATURALLY CONTAMINATED WELL WATER. METHODS: METHYLATION IN WHOLE BLOOD DNA WAS MEASURED AT [FORMULA: SEE TEXT] USING THE ILLUMINA INFINIUMMETHYLATIONEPIC (EPIC) ARRAY. TO ASSESS ASSOCIATIONS BETWEEN ARSENIC EXPOSURE AND CPG METHYLATION, WE USED LINEAR REGRESSION MODELS ADJUSTED FOR COVARIATES AND SURROGATE VARIABLES (SVS) (CAPTURING UNKNOWN TECHNICAL AND BIOLOGIC FACTORS). WE ATTEMPTED REPLICATION AND CONDUCTED A META-ANALYSIS USING AN INDEPENDENT DATASET OF [FORMULA: SEE TEXT] FROM 400 BANGLADESHI INDIVIDUALS WITH ARSENICAL SKIN LESIONS. RESULTS: WE IDENTIFIED 34 CPGS ASSOCIATED WITH [FORMULA: SEE TEXT] CREATININE-ADJUSTED URINARY ARSENIC [[FORMULA: SEE TEXT]]. SIXTEEN OF THESE CPGS ANNOTATED TO THE [FORMULA: SEE TEXT] ARRAY, AND 10 ASSOCIATIONS WERE REPLICATED ([FORMULA: SEE TEXT]). THE TOP TWO CPGS ANNOTATED UPSTREAM OF THE ABR GENE (CG01912040, CG10003262 ). ALL URINARY ARSENIC-ASSOCIATED CPGS WERE ALSO ASSOCIATED WITH ARSENIC CONCENTRATION MEASURED IN DRINKING WATER ([FORMULA: SEE TEXT]). META-ANALYSIS ([FORMULA: SEE TEXT] SAMPLES) IDENTIFIED 221 URINARY ARSENIC-ASSOCIATED CPGS ([FORMULA: SEE TEXT]). THE ARSENIC-ASSOCIATED CPGS FROM THE META-ANALYSIS WERE ENRICHED IN NON-CPG ISLANDS AND SHORES ([FORMULA: SEE TEXT]) AND DEPLETED IN PROMOTER REGIONS ([FORMULA: SEE TEXT]). AMONG THE ARSENIC-ASSOCIATED CPGS ([FORMULA: SEE TEXT]), WE OBSERVED SIGNIFICANT ENRICHMENT OF GENES ANNOTATING TO THE REACTIVE OXYGEN SPECIES PATHWAY, INFLAMMATORY RESPONSE, AND TUMOR NECROSIS FACTOR [FORMULA: SEE TEXT] ([FORMULA: SEE TEXT]) SIGNALING VIA NUCLEAR FACTOR KAPPA-B ([FORMULA: SEE TEXT]) HALLMARKS ([FORMULA: SEE TEXT]). CONCLUSIONS: THE NOVEL AND REPLICABLE ASSOCIATIONS BETWEEN ARSENIC EXPOSURE AND DNA METHYLATION AT SPECIFIC CPGS OBSERVED IN THIS WORK SUGGEST THAT EPIGENETIC ALTERATIONS SHOULD BE FURTHER INVESTIGATED AS POTENTIAL MEDIATORS IN ARSENIC TOXICITY AND AS BIOMARKERS OF EXPOSURE AND EFFECT IN EXPOSED POPULATIONS. HTTPS://DOI.ORG/10.1289/EHP3849. 2019 8 846 35 CHILDHOOD EXPOSURE TO AMBIENT POLYCYCLIC AROMATIC HYDROCARBONS IS LINKED TO EPIGENETIC MODIFICATIONS AND IMPAIRED SYSTEMIC IMMUNITY IN T CELLS. BACKGROUND: EVIDENCE SUGGESTS THAT EXPOSURE TO POLYCYCLIC AROMATIC HYDROCARBONS (PAHS) INCREASES ATOPY; IT IS UNCLEAR HOW PAH EXPOSURE IS LINKED TO INCREASED SEVERITY OF ATOPIC DISEASES. OBJECTIVE: WE HYPOTHESIZED THAT AMBIENT PAH EXPOSURE IS LINKED TO IMPAIRMENT OF IMMUNITY IN ATOPIC CHILDREN (DEFINED AS CHILDREN WITH ASTHMA AND/OR ALLERGIC RHINITIS) FROM FRESNO, CALIFORNIA, AN AREA WITH ELEVATED AMBIENT PAHS. METHODS: WE RECRUITED 256 SUBJECTS FROM FRESNO, CA. AMBIENT PAH CONCENTRATIONS (NG/M(3) ) WERE MEASURED USING A SPATIAL-TEMPORAL REGRESSION MODEL OVER MULTIPLE TIME PERIODS. ASTHMA DIAGNOSIS WAS DETERMINED BY CURRENT NHLBI CRITERIA. PHENOTYPING AND FUNCTIONAL IMMUNE MEASUREMENTS WERE PERFORMED FROM ISOLATED CELLS. FOR EPIGENETIC MEASUREMENTS, DNA WAS ISOLATED AND PYROSEQUENCED. RESULTS: WE SHOW THAT HIGHER AVERAGE PAH EXPOSURE WAS SIGNIFICANTLY ASSOCIATED WITH IMPAIRED TREG FUNCTION AND INCREASED METHYLATION IN THE FORKHEAD BOX PROTEIN 3 (FOXP3) LOCUS (P < 0.05), CONDITIONAL ON ATOPIC STATUS. THESE EPIGENETIC MODIFICATIONS WERE SIGNIFICANTLY LINKED TO DIFFERENTIAL PROTEIN EXPRESSION OF FOXP3 (P < 0.001). METHYLATION WAS ASSOCIATED WITH CELLULAR FUNCTIONAL CHANGES, SPECIFICALLY TREG DYSFUNCTION, AND AN INCREASE IN TOTAL PLASMA IGE LEVELS. PROTEIN EXPRESSION OF IL-10 DECREASED AND IFN-GAMMA INCREASED AS THE EXTENT OF PAH EXPOSURE INCREASED. THE STRENGTH OF THE ASSOCIATIONS GENERALLY INCREASED AS THE TIME WINDOW FOR AVERAGE PAH EXPOSURE INCREASED FROM 24 HR TO 1 YEAR, SUGGESTING MORE OF A CHRONIC RESPONSE. SIGNIFICANT ASSOCIATIONS WITH CHRONIC PAH EXPOSURE AND IMMUNE OUTCOMES WERE ALSO OBSERVED IN SUBJECTS WITH ALLERGIC RHINITIS. CONCLUSIONS AND CLINICAL RELEVANCE: COLLECTIVELY, THESE RESULTS DEMONSTRATE THAT INCREASED AMBIENT PAH EXPOSURE IS ASSOCIATED WITH IMPAIRED SYSTEMIC IMMUNITY AND EPIGENETIC MODIFICATIONS IN A KEY LOCUS INVOLVED IN ATOPY: FOXP3, WITH A HIGHER IMPACT ON ATOPIC CHILDREN. THE RESULTS SUGGEST THAT INCREASED ATOPIC CLINICAL SYMPTOMS IN CHILDREN COULD BE LINKED TO INCREASED PAH EXPOSURE IN AIR POLLUTION. 2015 9 4015 33 LOW-DOSE EXPOSURE TO BISPHENOLS A, F AND S OF HUMAN PRIMARY ADIPOCYTE IMPACTS CODING AND NON-CODING RNA PROFILES. BISPHENOL A (BPA) EXPOSURE HAS BEEN SUSPECTED TO BE ASSOCIATED WITH DELETERIOUS EFFECTS ON HEALTH INCLUDING OBESITY AND METABOLICALLY-LINKED DISEASES. ALTHOUGH BISPHENOLS F (BPF) AND S (BPS) ARE BPA STRUCTURAL ANALOGS COMMONLY USED IN MANY MARKETED PRODUCTS AS A REPLACEMENT FOR BPA, ONLY SPARSE TOXICOLOGICAL DATA ARE AVAILABLE YET. OUR OBJECTIVE WAS TO COMPREHENSIVELY CHARACTERIZE BISPHENOLS GENE TARGETS IN A HUMAN PRIMARY ADIPOCYTE MODEL, IN ORDER TO DETERMINE WHETHER THEY MAY INDUCE CELLULAR DYSFUNCTION, USING CHRONIC EXPOSURE AT TWO CONCENTRATIONS: A "LOW-DOSE" SIMILAR TO THE DOSE USUALLY ENCOUNTERED IN HUMAN BIOLOGICAL FLUIDS AND A HIGHER DOSE. THEREFORE, BPA, BPF AND BPS HAVE BEEN ADDED AT 10 NM OR 10 MUM DURING THE DIFFERENTIATION OF HUMAN PRIMARY ADIPOCYTES FROM SUBCUTANEOUS FAT OF THREE NON-DIABETIC CAUCASIAN FEMALE PATIENTS. GENE EXPRESSION (MRNA/LNCRNA) ARRAYS AND MICRORNA ARRAYS, HAVE BEEN USED TO ASSESS CODING AND NON-CODING RNA CHANGES. WE DETECTED SIGNIFICANTLY DEREGULATED MRNA/LNCRNA AND MIRNA AT LOW AND HIGH DOSES. ENRICHMENT IN "CANCER" AND "ORGANISMAL INJURY AND ABNORMALITIES" RELATED PATHWAYS WAS FOUND IN RESPONSE TO THE THREE PRODUCTS. SOME LONG INTERGENIC NON-CODING RNAS AND SMALL NUCLEOLAR RNAS WERE DIFFERENTIALLY EXPRESSED SUGGESTING THAT BISPHENOLS MAY ALSO ACTIVATE MULTIPLE CELLULAR PROCESSES AND EPIGENETIC MODIFICATIONS. THE ANALYSIS OF UPSTREAM REGULATORS OF DEREGULATED GENES HIGHLIGHTED HORMONES OR HORMONE-LIKE CHEMICALS SUGGESTING THAT BPS AND BPF CAN BE SUSPECTED TO INTERFERE, JUST LIKE BPA, WITH HORMONAL REGULATION AND HAVE TO BE CONSIDERED AS ENDOCRINE DISRUPTORS. ALL THESE RESULTS SUGGEST THAT AS BPA, ITS SUBSTITUTES BPS AND BPF SHOULD BE USED WITH THE SAME RESTRICTIONS. 2017 10 5497 39 REVIEW: ANIMAL MODELS OF ACQUIRED EPILEPSY: INSIGHTS INTO MECHANISMS OF HUMAN EPILEPTOGENESIS. IN MANY PATIENTS WHO SUFFER FROM EPILEPSIES, RECURRENT EPILEPTIC SEIZURES DO NOT START AT BIRTH BUT DEVELOP LATER IN LIFE. THIS HOLDS PARTICULARLY TRUE FOR EPILEPSIES WITH A FOCAL SEIZURE ORIGIN INCLUDING FOCAL CORTICAL DYSPLASIAS AND TEMPORAL LOBE EPILEPSY (TLE). TLE MOST FREQUENTLY HAS ITS SEIZURE ONSET IN THE HIPPOCAMPAL FORMATION. HIPPOCAMPAL BIOPSIES OF PHARMACORESISTANT TLE PATIENTS UNDERGOING EPILEPSY SURGERY FOR SEIZURE CONTROL MOST FREQUENTLY REVEAL THE DAMAGE PATTERN OF HIPPOCAMPAL SCLEROSIS, THAT IS, SEGMENTAL NEURONAL CELL LOSS AND CONCOMITANT ASTROGLIOSIS. MANY TLE PATIENTS REPORT ON TRANSIENT BRAIN INSULTS EARLY IN LIFE, WHICH IS FOLLOWED BY A 'LATENCY' PERIOD LACKING SEIZURE ACTIVITY OF MONTHS OR EVEN YEARS BEFORE CHRONIC RECURRENT SEIZURES START. THE PLETHORA OF STRUCTURAL AND CELLULAR MECHANISMS THAT CONVERT THE HIPPOCAMPAL FORMATION TO BECOME CHRONICALLY HYPEREXCITABLE AFTER A TRANSIENT INSULT TO THE BRAIN ARE SUMMARIZED UNDER THE TERM EPILEPTOGENESIS. IN CONTRAST TO THE OBSTACLES ARISING FOR EXPERIMENTAL STUDIES OF EPILEPTOGENESIS ASPECTS IN HUMAN SURGICAL HIPPOCAMPAL TISSUE, RECENT ANIMAL MODEL APPROACHES ALLOW INSIGHTS INTO MECHANISMS OF EPILEPTOGENESIS. RELEVANT MODELS OF TRANSIENT BRAIN INSULTS IN THIS CONTEXT COMPRISE SEVERAL DISTINCT TYPES OF LESIONS INCLUDING EXCITOXIC STATUS EPILEPTICUS (SE), ELECTRICAL SEIZURE INDUCTION, TRAUMATIC BRAIN INJURY, INDUCTION OF INFLAMMATORY PROCESSES BY HYPERTHERMIA AND VIRAL INFLAMMATION AND OTHERS. IN PATHOGENETIC TERMS, ABERRANT TRANSCRIPTIONAL AND EPIGENETIC REPROGRAMMING, ACQUIRED CHANNEL- AND SYNAPTOPATHIES, NEURONAL NETWORK AND BLOOD-BRAIN BARRIER DYSFUNCTION AS WELL AS INNATE AND ADAPTIVE IMMUNITY-MEDIATED DAMAGE PLAY MAJOR ROLES. IN SUBSEQUENT STEPS, RESPECTIVE ANIMAL MODELS HAVE BEEN USED IN ORDER TO TEST WHETHER THIS DYNAMIC PROCESS CAN BE EITHER RETARDED OR EVEN ABOLISHED BY INTERFERING WITH EPILEPTOGENIC MECHANISMS. WELL-CONTROLLED SUBSEQUENT ANALYSES OF EPILEPTOGENIC CASCADES CHARACTERIZED IN ANIMAL MODELS USING CAREFULLY STRATIFIED HUMAN HIPPOCAMPAL BIOPSIES TO EXPLOIT THE UNIQUE OPPORTUNITIES GIVEN BY THESE RARE AND PRECIOUS BRAIN TISSUE SAMPLES AIM TO TRANSLATE INTO NOVEL ANTIEPILEPTOGENIC APPROACHES. RESPECTIVE PRECLINICAL TESTS CAN OPEN ENTIRELY NEW PERSPECTIVES FOR TAILOR-MADE TREATMENTS IN PATIENTS WITH THE POTENTIAL TO AVOID THE EMERGENCE OF CHRONIC FOCAL SEIZURE EVENTS. 2018 11 4947 33 PATERNAL SEPSIS INDUCES ALTERATIONS OF THE SPERM METHYLOME AND DAMPENS OFFSPRING IMMUNE RESPONSES-AN ANIMAL STUDY. BACKGROUND: SEPSIS REPRESENTS THE UTMOST SEVERE CONSEQUENCE OF INFECTION, INVOLVING A DYSREGULATED AND SELF-DAMAGING IMMUNE RESPONSE OF THE HOST. WHILE DIFFERENT ENVIRONMENTAL EXPOSURES LIKE CHRONIC STRESS OR MALNUTRITION HAVE BEEN WELL DESCRIBED TO REPROGRAM THE GERMLINE AND SUBSEQUENTLY OFFSPRING ATTRIBUTES, THE INTERGENERATIONAL IMPACT OF SEPSIS AS A TREMENDOUS IMMUNOLOGICAL STRESSOR HAS NOT BEEN EXAMINED YET. METHODS: POLYMICROBIAL SEPSIS IN 12-WEEK-OLD MALE C57BL/6 MICE WAS INDUCED BY CECAL LIGATION AND PUNCTURE (CLP), FOLLOWED BY A MATING OF THE MALE SURVIVORS (OR APPROPRIATE SHAM CONTROL ANIMALS) 6 WEEKS LATER WITH HEALTHY FEMALES. ALVEOLAR MACROPHAGES OF OFFSPRING ANIMALS WERE ISOLATED AND STIMULATED WITH EITHER LPS OR ZYMOSAN, AND SUPERNATANT LEVELS OF TNF-ALPHA WERE QUANTIFIED BY ELISA. FURTHERMORE, SYSTEMIC CYTOKINE RESPONSE TO INTRAPERITONEALLY INJECTED LPS WAS ASSESSED AFTER 24 H. ALSO, MORPHOLOGY, MOTILITY, AND GLOBAL DNA METHYLATION OF THE SEPSIS SURVIVORS' SPERM WAS EXAMINED. RESULTS: COMPARATIVE REDUCED REDUCTION BISULFITE SEQUENCING (RRBS) OF SPERM REVEALED CHANGES OF DNA METHYLATION (N = 381), MOST PRONOUNCED IN THE INTERGENIC GENOME AS WELL AS WITHIN INTRONS OF DEVELOPMENTALLY RELEVANT GENES. OFFSPRING OF SEPSIS FATHERS EXHIBITED A SLIGHT DECREASE IN BODY WEIGHT, WITH A MORE PRONOUNCED WEIGHT DIFFERENCE IN MALE ANIMALS (CLP VS. SHAM). MALE DESCENDANTS OF SEPSIS FATHERS, BUT NOT FEMALE DESCENDANTS, EXHIBITED LOWER PLASMA CONCENTRATIONS OF IL-6, TNF-ALPHA, AND IL-10 24 H AFTER INJECTION OF LPS. IN LINE, ONLY ALVEOLAR MACROPHAGES OF MALE DESCENDANTS OF SEPSIS FATHERS PRODUCED LESS TNF-ALPHA UPON ZYMOSAN STIMULATION COMPARED TO SHAM DESCENDANTS, WHILE LPS RESPONSES KEPT UNCHANGED. CONCLUSION: WE CAN PROVE THAT MALE-BUT SURPRISINGLY NOT FEMALE-DESCENDANTS OF POST-SEPSIS FATHERS SHOW A DAMPENED SYSTEMIC AS WELL AS PULMONARY IMMUNE RESPONSE. BASED ON THIS OBSERVATION OF AN IMMUNE HYPO-RESPONSIVITY, WE PROPOSE THAT MALE DESCENDANTS OF SEPSIS FATHERS ARE AT RISK TO DEVELOP FUNGAL AND BACTERIAL INFECTIONS AND MIGHT BENEFIT FROM THERAPEUTIC IMMUNE MODULATION. 2018 12 4989 31 PCSK9 IS INCREASED IN CEREBROSPINAL FLUID OF INDIVIDUALS WITH ALCOHOL USE DISORDER. BACKGROUND: RECENT STUDIES HAVE SHOWN THAT ALCOHOL USE AFFECTS THE REGULATION AND EXPRESSION OF PROPROTEIN CONVERTASE SUBTILISIN/KEXIN 9 (PCSK9). WHILE A MAJOR ROLE OF PCSK9 IN HEPATIC FUNCTION AND LIPID REGULATION HAS BEEN CLEARLY ESTABLISHED, OTHER PLEIOTROPIC EFFECTS REMAIN POORLY UNDERSTOOD. EXISTING RESEARCH SUGGESTS A POSITIVE ASSOCIATION BETWEEN PCSK9 EXPRESSION IN THE BRAIN AND PSYCHOPATHOLOGY, WITH INCREASED LEVELS OF PCSK9 IN THE CEREBROSPINAL FLUID (CSF) OF INDIVIDUALS WITH DEMENTIA AND EPIGENETIC MODIFICATIONS OF PCSK9 ASSOCIATED WITH ALCOHOL USE DISORDER (AUD). IN THIS STUDY, WE HYPOTHESIZED THAT CHRONIC ALCOHOL USE WOULD INCREASE PCSK9 EXPRESSION IN CSF. METHODS: PCSK9 LEVELS IN CSF WERE MEASURED IN INDIVIDUALS WITH AUD (N = 42) ADMITTED TO AN INPATIENT REHABILITATION PROGRAM AND CONTROLS (N = 25). CSF SAMPLES IN AUD WERE ASSESSED AT 2 TIME POINTS, AT DAY 5 AND DAY 21 AFTER ADMISSION. FURTHERMORE, PLASMA SAMPLES WERE COLLECTED AND MEASURED FROM THE INDIVIDUALS WITH AUD. RESULTS: PCSK9 IN CSF WAS SIGNIFICANTLY INCREASED IN THE AUD GROUP AT DAY 5 AND DAY 21 COMPARED TO THE CONTROLS (P < 0.0001). PLASMA PCSK9 LEVELS WERE CORRELATED POSITIVELY WITH CSF PCSK9 LEVELS IN AUD (P = 0.0493). CONCLUSIONS: OUR DATA SUGGEST THAT PCSK9 IS ELEVATED IN THE CSF OF INDIVIDUALS WITH AUD, WHICH MAY INDICATE A POTENTIAL ROLE OF PCSK9 IN AUD. ADDITIONAL STUDIES ARE NECESSARY TO FURTHER ELUCIDATE THE FUNCTIONS OF PCSK9 IN THE BRAIN. 2019 13 3934 41 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 14 4010 30 LOW MATERNAL ADHERENCE TO A MEDITERRANEAN DIET IS ASSOCIATED WITH INCREASE IN METHYLATION AT THE MEG3-IG DIFFERENTIALLY METHYLATED REGION IN FEMALE INFANTS. DIET IS DICTATED BY THE SURROUNDING ENVIRONMENT, AS FOOD ACCESS AND AVAILABILITY MAY CHANGE DEPENDING ON WHERE ONE LIVES. MATERNAL DIET DURING PREGNANCY IS AN IMPORTANT PART OF THE IN UTERO ENVIRONMENT, AND MAY AFFECT THE EPIGENOME. STUDIES LOOKING AT OVERALL DIET PATTERN IN RELATION TO DNA METHYLATION HAVE BEEN LACKING. THE MEDITERRANEAN DIET IS KNOWN FOR ITS HEALTH BENEFITS, INCLUDING DECREASED INFLAMMATION, WEIGHT LOSS, AND MANAGEMENT OF CHRONIC DISEASES. THIS STUDY ASSESSES THE ASSOCIATION BETWEEN MATERNAL ADHERENCE TO A MEDITERRANEAN DIET PATTERN DURING PREGNANCY AND INFANT DNA METHYLATION AT BIRTH. MEDITERRANEAN DIET ADHERENCE IN EARLY PREGNANCY WAS MEASURED IN 390 WOMEN ENROLLED IN THE NEWBORN EPIGENETIC STUDY, AND DNA METHYLATION WAS ASSESSED IN THEIR INFANTS AT BIRTH. MULTINOMIAL LOGISTIC REGRESSION WAS USED TO ASSESS THE ASSOCIATION BETWEEN ADHERENCE TO A MEDITERRANEAN DIET AND INFANT METHYLATION AT THE MEG3, MEG3-IG, PLEIOMORPHIC ADENOMA GENE-LIKE 1, INSULIN-LIKE GROWTH FACTOR 2 GENE, H19, MESODERM-SPECIFIC TRANSCRIPT, NEURONATIN, PATERNALLY EXPRESSED GENE 3, SARCOGLYCAN AND PATERNALLY EXPRESSED GENE 10 REGIONS, MEASURED BY PYROSEQUENCING. INFANTS OF MOTHERS WITH A LOW ADHERENCE TO A MEDITERRANEAN DIET HAD A GREATER ODDS OF HYPO-METHYLATION AT THE MEG3-IG DIFFERENTIALLY METHYLATED REGION (DMR). SEX-STRATIFIED MODELS SHOWED THAT THIS ASSOCIATION WAS PRESENT IN GIRLS ONLY. THIS STUDY PROVIDES EARLY EVIDENCE ON THE ASSOCIATION BETWEEN OVERALL DIET PATTERN AND METHYLATION AT THE 9 DMRS INCLUDED IN THIS STUDY, AND SUGGESTS THAT MATERNAL DIET CAN HAVE A SEX-SPECIFIC IMPACT ON INFANT DNA METHYLATION AT SPECIFIC IMPRINTED DMRS. 2017 15 418 34 ANCESTRAL EXPOSURE TO STRESS EPIGENETICALLY PROGRAMS PRETERM BIRTH RISK AND ADVERSE MATERNAL AND NEWBORN OUTCOMES. BACKGROUND: CHRONIC STRESS IS CONSIDERED TO BE ONE OF MANY CAUSES OF HUMAN PRETERM BIRTH (PTB), BUT NO DIRECT EVIDENCE HAS YET BEEN PROVIDED. HERE WE SHOW IN RATS THAT STRESS ACROSS GENERATIONS HAS DOWNSTREAM EFFECTS ON ENDOCRINE, METABOLIC AND BEHAVIOURAL MANIFESTATIONS OF PTB POSSIBLY VIA MICRORNA (MIRNA) REGULATION. METHODS: PREGNANT DAMS OF THE PARENTAL GENERATION WERE EXPOSED TO STRESS FROM GESTATIONAL DAYS 12 TO 18. THEIR PREGNANT DAUGHTERS (F1) AND GRAND-DAUGHTERS (F2) EITHER WERE STRESSED OR REMAINED AS NON-STRESSED CONTROLS. GESTATIONAL LENGTH, MATERNAL GESTATIONAL WEIGHT GAIN, BLOOD GLUCOSE AND PLASMA CORTICOSTERONE LEVELS, LITTER SIZE AND OFFSPRING WEIGHT GAIN FROM POSTNATAL DAYS 1 TO 30 WERE RECORDED IN EACH GENERATION, INCLUDING F3. MATERNAL BEHAVIOURS WERE ANALYSED FOR THE FIRST HOUR AFTER COMPLETED PARTURITION, AND OFFSPRING SENSORIMOTOR DEVELOPMENT WAS RECORDED ON POSTNATAL DAY (P) 7. F0 THROUGH F2 MATERNAL BRAIN FRONTAL CORTEX, UTERUS AND PLACENTA MIRNA AND GENE EXPRESSION PATTERNS WERE USED TO IDENTIFY STRESS-INDUCED EPIGENETIC REGULATORY PATHWAYS OF MATERNAL BEHAVIOUR AND PREGNANCY MAINTENANCE. RESULTS: PROGRESSIVELY UP TO THE F2 GENERATION, STRESS GRADUALLY REDUCED GESTATIONAL LENGTH, MATERNAL WEIGHT GAIN AND BEHAVIOURAL ACTIVITY, AND INCREASED BLOOD GLUCOSE LEVELS. REDUCED OFFSPRING GROWTH AND DELAYED BEHAVIOURAL DEVELOPMENT IN THE STRESS COHORT WAS RECOGNIZABLE AS EARLY AS P7, WITH THE GREATEST EFFECT IN THE F3 OFFSPRING OF TRANSGENERATIONALLY STRESSED MOTHERS. FURTHERMORE, STRESS ALTERED MIRNA EXPRESSION PATTERNS IN THE BRAIN AND UTERUS OF F2 MOTHERS, INCLUDING THE MIR-200 FAMILY, WHICH REGULATES PATHWAYS RELATED TO BRAIN PLASTICITY AND PARTURITION, RESPECTIVELY. MAIN MIR-200 FAMILY TARGET GENES IN THE UTERUS, STAT5B, ZEB1 AND ZEB2, WERE DOWNREGULATED BY MULTIGENERATIONAL STRESS IN THE F1 GENERATION. ZEB2 WAS ALSO REDUCED IN THE STRESSED F2 GENERATION, SUGGESTING A CAUSAL MECHANISM FOR DISTURBED PREGNANCY MAINTENANCE. ADDITIONALLY, STRESS INCREASED PLACENTAL MIR-181A, A MARKER OF HUMAN PTB. CONCLUSIONS: THE FINDINGS INDICATE THAT A FAMILY HISTORY OF STRESS MAY PROGRAM CENTRAL AND PERIPHERAL PATHWAYS REGULATING GESTATIONAL LENGTH AND MATERNAL AND NEWBORN HEALTH OUTCOMES IN THE MATERNAL LINEAGE. THIS NEW PARADIGM MAY MODEL THE ORIGIN OF MANY HUMAN PTB CAUSES. 2014 16 5010 32 PEROXIDATION OF LINOLEIC, ARACHIDONIC AND OLEIC ACID IN RELATION TO THE INDUCTION OF OXIDATIVE DNA DAMAGE AND CYTOGENETIC EFFECTS. IN THE PRESENT STUDY, THE POSSIBLE ROLE OF THE POLYUNSATURATED FATTY ACIDS LINOLEIC AND ARACHIDONIC ACID IN THE CHEMICAL INDUCTION OF CARCINOGENESIS HAS BEEN INVESTIGATED. ANALYSIS OF 7,8-DIHYDRO-8-OXO-2'-DEOXYGUANOSINE (8-OXODG) LEVELS IN 2'-DEOXYGUANOSINE (DG) AND ISOLATED DNA HAS DEMONSTRATED THAT LINOLEIC AND ARACHIDONIC ACID ARE CAPABLE OF INDUCING THIS SPECIFIC GENOTOXIC DAMAGE. THIS EFFECT APPEARS TO BE RELATED TO THE DEGREE OF FATTY ACID UNSATURATION, SINCE IT WAS NOT INDUCED BY MONOUNSATURATED OLEIC ACID. ENZYMATIC PEROXIDATION OF LINOLEIC AND ARACHIDONIC ACID RESULTED IN A SIGNIFICANT INCREASE IN OXIDATIVE DNA DAMAGE. STUDIES ON THE INTERFERENCE OF RADICAL SCAVENGERS WITH THE INDUCTION OF 8-OXODG IN COMBINATION WITH ELECTRON SPIN RESONANCE SPECTROSCOPY DEMONSTRATED THAT THE SUPEROXIDE ANION WAS GENERATED DURING PEROXIDATION OF THESE FATTY ACIDS AND THAT SINGLET OXYGEN IS MOST LIKELY INVOLVED IN THE FORMATION OF OXIDATIVE DNA DAMAGE. THE LEVEL OF OXIDATIVE DAMAGE IN DG AND SINGLE-STRANDED DNA WAS HIGHER AS COMPARED TO THAT IN NATIVE DNA AFTER EQUIMOLAR TREATMENT. EXPOSURE OF HUMAN LYMPHOCYTES TO LINOLEIC OR ARACHIDONIC ACID DID NOT RESULT IN A SIGNIFICANT INCREASE IN LEVELS OF 8-OXODG. THIS MAY INDICATE THAT THE RATE OF INTRACELLULAR PEROXIDATION IS RELATIVELY LOW AND/OR THAT NUCLEAR DNA IN INTACT CELLS IS EFFECTIVELY PROTECTED AGAINST GENETIC DAMAGE INDUCED BY REACTIVE OXYGEN SPECIES. IT IS THEREFORE CONCLUDED THAT RELATIVELY SHORT PERIODS OF LINOLEIC OR ARACHIDONIC ACID ADMINISTRATION ARE NOT LIKELY TO IMPOSE A DIRECT GENOTOXIC RISK. IT CAN, HOWEVER, NOT BE EXCLUDED THAT CHRONIC EXPOSURE TO POLYUNSATURATED FATTY ACIDS INDUCES OXIDATIVE DNA DAMAGE OR IS RELATED TO CANCER RISK BY EPIGENETIC MECHANISMS, AS IS ALSO INDICATED BY THE OBSERVED CYTOTOXIC EFFECTS OF LINOLEIC AND ARACHIDONIC ACID. 1994 17 3971 42 LONG-LASTING NEUROTOXIC EFFECTS OF EXPOSURE TO METHYLMERCURY DURING DEVELOPMENT. AMONGST ENVIRONMENTAL CHEMICAL CONTAMINANTS, METHYLMERCURY (MEHG) REMAINS A MAJOR CONCERN BECAUSE OF ITS DETRIMENTAL EFFECTS ON DEVELOPING ORGANISMS, WHICH APPEAR TO BE PARTICULARLY SUSCEPTIBLE TO ITS TOXICITY. HERE, WE INVESTIGATED THE EFFECTS OF LOW MEHG LEVELS ON THE DEVELOPMENT OF THE NERVOUS SYSTEM USING BOTH IN VITRO AND IN VIVO EXPERIMENTAL MODELS. IN NEURAL STEM CELLS (NSCS), MEHG DECREASED PROLIFERATION AND NEURONAL DIFFERENTIATION AND INDUCED CELLULAR SENESCENCE ASSOCIATED WITH IMPAIRMENT IN MITOCHONDRIAL FUNCTION AND A CONCOMITANT DECREASE IN GLOBAL DNA METHYLATION. INTERESTINGLY, THE EFFECTS WERE HERITABLE AND COULD BE OBSERVED IN DAUGHTER NSCS NEVER DIRECTLY EXPOSED TO MEHG. BY CHRONICALLY EXPOSING PREGNANT/LACTATING MICE TO MEHG, WE FOUND PERSISTENT BEHAVIOURAL CHANGES IN THE MALE OFFSPRING, WHICH EXHIBITED DEPRESSION-LIKE BEHAVIOUR THAT COULD BE REVERSED BY CHRONIC TREATMENT WITH THE ANTIDEPRESSANT FLUOXETINE. THE BEHAVIOURAL ALTERATIONS WERE ASSOCIATED WITH A DECREASED NUMBER OF PROLIFERATING CELLS AND LOWER EXPRESSION OF BRAIN-DERIVED NEUROTROPHIC FACTOR (BDNF) MRNA IN THE HIPPOCAMPAL DENTATE GYRUS. MEHG EXPOSURE ALSO INDUCED LONG-LASTING DNA HYPERMETHYLATION, INCREASED HISTONE H3-K27 TRI-METHYLATION AND DECREASED H3 ACETYLATION AT THE BDNF PROMOTER IV, INDICATING THAT EPIGENETIC MECHANISMS PLAY A CRITICAL ROLE IN MEDIATING THE LONG-LASTING EFFECTS OF PERINATAL EXPOSURE TO MEHG. FLUOXETINE TREATMENT RESTORED THE BDNF MRNA EXPRESSION LEVELS, AS WELL AS THE NUMBER OF PROLIFERATING CELLS IN THE GRANULE CELL LAYER OF THE DENTATE GYRUS, WHICH FURTHER SUPPORTS THE HYPOTHESIS THAT LINKS DEPRESSION TO IMPAIRED NEUROGENESIS. ALTOGETHER, OUR FINDINGS HAVE SHOWN THAT LOW CONCENTRATIONS OF MEHG INDUCE LONG-LASTING EFFECTS IN NSCS THAT CAN POTENTIALLY PREDISPOSE INDIVIDUALS TO DEPRESSION, WHICH WE HAVE REPORTED EARLIER TO OCCUR IN EXPERIMENTAL ANIMALS EXPOSED TO MEHG DURING PRENATAL AND EARLY POSTNATAL DEVELOPMENT. 2013 18 73 29 A MULTI-GENERATIONAL STUDY ON LOW-DOSE BPA EXPOSURE IN WISTAR RATS: EFFECTS ON MATERNAL BEHAVIOR, FLAVOR INTAKE AND DEVELOPMENT. BISPHENOL A (BPA) IS A COMMON ENDOCRINE DISRUPTOR FOUND AS AN ENVIRONMENTAL AND FOOD CONTAMINANT. IT EXERTS BOTH DEVELOPMENTAL AND BEHAVIORAL EFFECTS, MAINLY WHEN EXPOSURE OCCURS IN EARLY LIFE. THE AIM OF THIS STUDY WAS TO DETERMINE THE MULTI-GENERATIONAL EFFECTS OF CHRONIC, HUMAN-RELEVANT LOW-DOSE EXPOSURE TO BPA ON DEVELOPMENT, MATERNAL BEHAVIOR AND FLAVOR PREFERENCE IN WISTAR RATS. BPA WAS ORALLY ADMINISTERED AT A DAILY DOSE OF 5 MUG/KG BODY WEIGHT TO F0 PREGNANT DAMS FROM THE FIRST DAY OF GESTATION (GD 1) UNTIL THE LAST DAY OF LACTATION (LD 21), AND THEN TO F1 OFFSPRING FROM WEANING (PND 21) TO ADULTHOOD (PND 100). F2 OFFSPRING WERE NOT EXPOSED. DEVELOPMENT AND CLINICAL SIGNS OF TOXICITY WERE ASSESSED DAILY. MATERNAL BEHAVIOR WAS EVALUATED BY OBSERVING NURSING AND PUP-CARING ACTIONS, AS WELL AS "NON-MATERNAL" BEHAVIORS IN F0 AND F1 DAMS FROM PARTURITION UNTIL LD 8. THE FLAVOR PREFERENCES OF F1 AND F2 OFFSPRING WERE EVALUATED BASED ON THE INTAKE OF SWEET, SALT AND FAT SOLUTIONS USING THE TWO-BOTTLE CHOICE TEST ON PND 21-34 AND PND 86-99. BPA EXPOSURE: 1) DECREASED MATERNAL BEHAVIOR IN F1 DAMS, 2) CAUSED DEVELOPMENTAL DEFECTS IN BOTH F1 AND F2 OFFSPRING, WITH A NOTICEABLE DECREASE IN ANOGENITAL DISTANCE IN MALE RATS, AND 3) DID NOT AFFECT FLAVORED SOLUTION INTAKE IN F1, BUT INDUCED CHANGES IN SWEET PREFERENCE IN F2 JUVENILES AND IN SALT AND FAT SOLUTION INTAKES IN F2 ADULTS, AND 4) INDUCED A BODY WEIGHT INCREASE IN THE F2 GENERATION ONLY, WHEREAS FOOD INTAKE AND WATER CONSUMPTION DID NOT CHANGE. TAKEN AS A WHOLE, OUR FINDINGS SHOWED THAT BOTH GESTATIONAL (F0) AND LIFELONG (F1) EXPOSURES TO A HUMAN-RELEVANT DOSE OF BPA COULD INDUCE MULTI-GENERATIONAL EFFECTS ON BOTH DEVELOPMENT AND BEHAVIOR. THESE RESULTS SUGGEST POSSIBLE SELECTIVE NEUROENDOCRINE DEFECTS AND/OR EPIGENETIC CHANGES CAUSED BY BPA EXPOSURE. 2014 19 518 29 ASSOCIATIONS BETWEEN ANTIBIOTIC EXPOSURE DURING PREGNANCY, BIRTH WEIGHT AND ABERRANT METHYLATION AT IMPRINTED GENES AMONG OFFSPRING. OBJECTIVES: LOW BIRTH WEIGHT (LBW) HAS BEEN ASSOCIATED WITH COMMON ADULT-ONSET CHRONIC DISEASES, INCLUDING OBESITY, CARDIOVASCULAR DISEASE, TYPE II DIABETES AND SOME CANCERS. THE ETIOLOGY OF LBW IS MULTI-FACTORIAL. HOWEVER, RECENT EVIDENCE SUGGESTS EXPOSURE TO ANTIBIOTICS MAY ALSO INCREASE THE RISK OF LBW. THE MECHANISMS UNDERLYING THIS ASSOCIATION ARE UNKNOWN, ALTHOUGH EPIGENETIC MECHANISMS ARE HYPOTHESIZED. IN THIS STUDY, WE EVALUATED THE ASSOCIATION BETWEEN MATERNAL ANTIBIOTIC USE AND LBW AND EXAMINED THE POTENTIAL ROLE OF ALTERED DNA METHYLATION THAT CONTROLS GROWTH REGULATORY IMPRINTED GENES IN THESE ASSOCIATIONS. METHODS: BETWEEN 2009-2011, 397 PREGNANT WOMEN WERE ENROLLED AND FOLLOWED UNTIL DELIVERY. PRENATAL ANTIBIOTIC USE WAS ASCERTAINED THROUGH MATERNAL SELF-REPORT. IMPRINTED GENES METHYLATION LEVELS WERE MEASURED AT DIFFERENTIALLY METHYLATED REGIONS (DMRS) USING BISULFITE PYROSEQUENCING. GENERALIZED LINEAR MODELS WERE USED TO EXAMINE ASSOCIATIONS AMONG ANTIBIOTIC USE, BIRTH WEIGHT AND DMR METHYLATION FRACTIONS. RESULTS: AFTER ADJUSTING FOR INFANT GENDER, RACE/ETHNICITY, MATERNAL BODY MASS INDEX, DELIVERY ROUTE, GESTATIONAL WEIGHT GAIN, GESTATIONAL AGE AT DELIVERY, FOLIC ACID INTAKE, PHYSICAL ACTIVITY, MATERNAL SMOKING AND PARITY, ANTIBIOTIC USE DURING PREGNANCY WAS ASSOCIATED WITH 138 G LOWER BIRTH WEIGHT COMPARED WITH NON-ANTIBIOTIC USE (BETA-COEFFICIENT=-132.99, S.E.=50.70, P=0.008). THESE ASSOCIATIONS WERE STRONGEST IN NEWBORNS OF WOMEN WHO REPORTED ANTIBIOTIC USE OTHER THAN PENICILLINS (BETA-COEFFICIENT=-135.57, S.E.=57.38, P=0.02). METHYLATION AT FIVE DMRS, IGF2 (P=0.05), H19 (P=0.15), PLAGL1 (P=0.01), MEG3 (P=0.006) AND PEG3 (P=0.08), WAS ASSOCIATED WITH MATERNAL ANTIBIOTIC USE; AMONG THESE, ONLY METHYLATION AT THE PLAGL1 DMR WAS ALSO ASSOCIATED WITH BIRTH WEIGHT. CONCLUSION: WE REPORT AN INVERSE ASSOCIATION BETWEEN IN UTERO EXPOSURE TO ANTIBIOTICS AND LOWER INFANT BIRTH WEIGHT AND PROVIDE THE FIRST EMPIRICAL EVIDENCE SUPPORTING IMPRINTED GENE PLASTICITY IN THESE ASSOCIATIONS. 2013 20 1087 39 COCAINE ALTERS THE MOUSE TESTICULAR EPIGENOME WITH DIRECT IMPACT ON HISTONE ACETYLATION AND DNA METHYLATION MARKS. RESEARCH QUESTION: RECENT EVIDENCE SUGGESTS THAT COCAINE ADMINISTRATION IN ANIMAL MODELS CAN TRIGGER NON-GENETIC INHERITANCE OF ADDICTION TRAITS FROM FATHER TO OFFSPRING, AFFECTING DEVELOPMENT AND BEHAVIOUR. IS CHRONIC COCAINE INTAKE INVOLVED IN ALTERATIONS OF EPIGENETIC HOMEOSTASIS IN THE TESTIS? DESIGN: EPIGENETIC MARKS AND MEDIATORS IN TESTIS AND ISOLATED GERM CELLS OF ADULT MICE TREATED WITH COCAINE (10 MG/KG) OR VEHICLE (STERILE SALINE SOLUTION) WERE EVALUATED IN AN INTERMITTENT BINGE PROTOCOL: THREE INTRAPERITONEAL INJECTIONS, 1 H APART, ONE DAY ON/OFF FOR 13 DAYS, COLLECTING TISSUE 24 H AFTER THE LAST BINGE ADMINISTRATION (DAY 14). RESULTS: IT WAS SHOWN THAT CHRONIC COCAINE INTAKE IN MICE DISRUPTS TESTICULAR EPIGENETIC HOMEOSTASIS, INCREASING GLOBAL METHYLATED CYTOSINE LEVELS IN DNA FROM GERM CELLS AND SPERM. COCAINE ALSO INCREASED TESTICULAR AND GERM CELL ACETYLATED HISTONE 3 AND 4 AND DECREASED EXPRESSION OF HISTONE DEACETYLASES HDAC1/2. IMMUNOLOCALIZATION STUDIES SHOWED THAT HDAC1/2 AND ACETYLATED HISTONE 3 AND 4 PROTEINS LOCALIZE TO MEIOTIC GERM CELLS. ANALYSIS OF MRNA EXPRESSION IN ISOLATED GERM CELLS SHOWS DECREASED LEVELS OF HDAC1/2/8, DNMT3B AND TET1 AND INCREASED LEVELS OF DNMT3A GENE EXPRESSION AFTER COCAINE TREATMENT. CONCLUSIONS: COCAINE INTAKE IS ASSOCIATED WITH TESTICULAR TOXICITY AND SIGNIFICANT REPRODUCTIVE FUNCTION IMPAIRMENT. THE RESULTS PRESENTED HERE BROADEN THE BASIC KNOWLEDGE OF THE IMPACT OF ADDICTIVE STIMULANTS ON TESTICULAR PATHOPHYSIOLOGY, FERTILITY AND MALE REPRODUCTIVE HEALTH AND IMPLY THAT ALTERED EPIGENETIC HOMEOSTASIS BY COCAINE MAY HAVE POTENTIAL CONSEQUENCES ON FUTURE GENERATIONS. 2018