1 4819 114 OCCURRENCE OF TOXICITY AND CELL PROLIFERATION AFTER A SINGLE GAVAGE ADMINISTRATION OF CHLOROFORM TO MALE F344 RATS. CHLOROFORM, AN INDUSTRIAL SOLVENT AND ONE OF THE MOST COMMON ENVIRONMENTAL CONTAMINANTS WHICH PRODUCES CARCINOGENIC EFFECTS IN THE LIVER AND KIDNEY OF RODENTS, IS NOT GENOTOXIC IN MOST TRADITIONAL BACTERIAL AND MAMMALIAN TEST SYSTEMS. ITS CARCINOGENIC POTENTIAL APPEARS ATTRIBUTABLE TO THE SUSTAINED CELL TURNOVER (REGENERATIVE HYPERPLASIA) WHICH RESULTS FROM CHRONIC CHLOROFORM TOXICITY. IN THIS PRESENT STUDY, CELL PROLIFERATION (REPLICATIVE DNA SYNTHESIS, RDS) AND HISTOPATHOLOGICAL CHANGES IN HEPATOCYTES AND RENAL TUBULAR EPITHELIAL CELLS WERE ASSESSED IN MALE F344 RATS FOLLOWING A SINGLE GAVAGE CHLOROFORM EXPOSURE (50, 150 OR 500 MG/KG). IN ADDITION, BIOCHEMICAL PARAMETERS (BUN, GOT, LDH AND NAG) WERE EXAMINED USING PLASMA AND URINE SAMPLES. CELL PROLIFERATION AND HISTOPATHOLOGICAL CHANGES (E.G. HYPERTROPHY, NECROSIS, VACUOLATION) WERE ONLY SEEN AT THE DOSE OF 500 MG/KG IN THE LIVER AND KIDNEY. AT THE SAME DOSE, ALL BIOCHEMICAL MARKERS WERE INCREASED AT THE 24 TO 48 HR TIME POINTS. THESE RESULTS OBTAINED ARE THUS IN LINE WITH EARLIER FINDINGS POINTING TO EPIGENETIC CARCINOGENICITY. 1998 2 3623 39 IN VIVO COMET ASSAY ON ISOLATED KIDNEY CELLS TO DISTINGUISH GENOTOXIC CARCINOGENS FROM EPIGENETIC CARCINOGENS OR CYTOTOXIC COMPOUNDS. THE OBJECTIVE OF THIS STUDY WAS TO DETERMINE THE ABILITY OF THE ALKALINE IN VIVO COMET ASSAY (PH>13) TO DISTINGUISH GENOTOXIC CARCINOGENS FROM EPIGENETIC CARCINOGENS WHEN PERFORMED ON FRESHLY ISOLATED KIDNEY CELLS AND TO DETERMINE THE POSSIBLE INTERFERENCE OF CYTOTOXICITY BY ASSESSING DNA DAMAGE INDUCED BY RENAL GENOTOXIC, EPIGENETIC OR TOXIC COMPOUNDS AFTER ENZYMATIC ISOLATION OF KIDNEY CELLS FROM OFA SPRAGUE-DAWLEY MALE RATS. THE ABILITY OF THE COMET ASSAY TO DISTINGUISH (1) GENOTOXICITY VERSUS CYTOTOXICITY AND (2) GENOTOXIC VERSUS NON-GENOTOXIC (EPIGENETIC) CARCINOGENS, WAS THUS INVESTIGATED BY STUDYING FIVE KNOWN GENOTOXIC RENAL CARCINOGENS ACTING THROUGH DIVERSE MECHANISMS OF ACTION, I.E. STREPTOZOTOCIN, ARISTOLOCHIC ACIDS, 2-NITROANISOLE, POTASSIUM BROMATE AND CISPLATIN, TWO RODENT RENAL EPIGENETIC CARCINOGENS: D-LIMONENE AND CICLOSPORINE AND TWO NEPHROTOXIC COMPOUNDS: STREPTOMYCIN AND INDOMETHACIN. ANIMALS WERE TREATED ONCE WITH THE TEST COMPOUND BY THE APPROPRIATE ROUTE OF ADMINISTRATION AND GENOTOXIC EFFECTS WERE MEASURED AT THE TWO SAMPLING TIMES OF 3-6 AND 22-26H AFTER TREATMENT. REGARDING THE TISSUE PROCESSING, THE LIMITED BACKGROUND LEVEL OF DNA MIGRATION OBSERVED IN THE NEGATIVE CONTROL GROUPS THROUGHOUT ALL EXPERIMENTS DEMONSTRATED THAT THE ENZYMATIC ISOLATION METHOD IMPLEMENTED IN THE CURRENT STUDY IS APPROPRIATE. ON THE OTHER HAND, STREPTOZOTOCIN, 20MG/KG, USED AS POSITIVE REFERENCE CONTROL CONCURRENTLY TO EACH ASSAY, CAUSED A CLEAR INCREASE IN THE MEAN OLIVE TAIL MOMENT MEDIAN VALUE, WHICH ALLOWS VALIDATING THE CURRENT METHODOLOGY. UNDER THESE EXPERIMENTAL CONDITIONS, THE IN VIVO RODENT COMET ASSAY DEMONSTRATED GOOD SENSITIVITY AND GOOD SPECIFICITY: ALL THE FIVE RENAL GENOTOXIC CARCINOGENS WERE CLEARLY DETECTED IN AT LEAST ONE EXPRESSION PERIOD EITHER DIRECTLY OR INDIRECTLY, AS IN THE CASE OF CISPLATIN: FOR THIS CROSS-LINKING AGENT, THE SIGNIFICANT DECREASE IN DNA MIGRATION OBSERVED UNDER STANDARD ELECTROPHORESIS CONDITIONS WAS CLEARLY AMPLIFIED WHEN THE DURATION OF ELECTROPHORESIS WAS INCREASED UP TO 40MIN. IN CONTRAST, EPIGENETIC AND NEPHROTOXIC COMPOUNDS FAILED TO INDUCE ANY SIGNIFCANT INCREASE IN DNA MIGRATION. IN CONCLUSION, THE IN VIVO RODENT COMET ASSAY PERFORMED ON ISOLATED KIDNEY CELLS COULD BE USED AS A TOOL TO INVESTIGATE THE GENOTOXIC POTENTIAL OF A TEST COMPOUND IF NEOPLASIC/PRENEOPLASIC CHANGES OCCUR AFTER SUBCHRONIC OR CHRONIC TREATMENTS, IN ORDER TO DETERMINE THE ROLE OF GENOTOXICITY IN TUMOR INDUCTION. MOREOVER, THE EPIGENETIC CARCINOGENS AND CYTOTOXIC COMPOUNDS DISPLAYED CLEARLY NEGATIVE RESPONSES IN THIS STUDY. THESE RESULTS ALLOW EXCLUDING A DNA DIRECT-ACTING MECHANISM OF ACTION AND CAN THUS SUGGEST THAT A THRESHOLD EXISTS. THEREFORE, THE CURRENT IN VIVO RODENT COMET ASSAY COULD CONTRIBUTE TO ELUCIDATE AN EPIGENETIC MECHANISM AND THUS, TO UNDERTAKE A RISK ASSESSMENT ASSOCIATED WITH HUMAN USE, DEPENDING ON THE EXPOSURE LEVEL. 2007 3 3981 28 LONG-TERM EPIGENETIC THERAPY WITH ORAL ZEBULARINE HAS MINIMAL SIDE EFFECTS AND PREVENTS INTESTINAL TUMORS IN MICE. RECENT SUCCESSES IN THE APPLICATION OF EPIGENETIC DRUGS FOR THE TREATMENT OF MYELODYSPLASTIC SYNDROME HAVE RAISED QUESTIONS ON THE SAFETY OF LONG-TERM ADMINISTRATION OF DNA METHYLATION INHIBITORS. WE TREATED PREWEANED CANCER PRONE APC(MIN/+) (MIN) MICE CONTINUOUSLY WITH THE DNA METHYLATION INHIBITOR ZEBULARINE IN THEIR DRINKING WATER TO DETERMINE THE EFFECTS OF THE DRUG ON NORMAL MOUSE DEVELOPMENT AS WELL AS CANCER PREVENTION. ZEBULARINE CAUSED A TISSUE-SPECIFIC REDUCTION IN DNA METHYLATION AT B1 SHORT INTERSPERSED NUCLEOTIDE ELEMENTS IN THE SMALL AND LARGE INTESTINES OF FEMALE MIN MICE BUT NOT IN OTHER ORGANS EXAMINED AFTER CHRONIC ORAL TREATMENT. NO SIGNIFICANT DIFFERENCE IN THE AVERAGE WEIGHTS OF MICE WAS OBSERVED DURING THE TREATMENT. IN ADDITION, ANALYSIS OF GLOBAL GENE EXPRESSION OF COLONIC EPITHELIAL CELLS FROM THE FEMALES INDICATED THAT ONLY 3% TO 6% OF THE GENES WERE AFFECTED IN THEIR EXPRESSION. WE DID NOT DETECT TOXICITY AND ABNORMALITIES FROM THE HISTOPATHOLOGIC ANALYSIS OF LIVER AND INTESTINAL TISSUES. LASTLY, WE TESTED WHETHER PREVENTION OF TUMORIGENESIS CAN BE ACHIEVED WITH CHRONIC ORAL ADMINISTRATION OF ZEBULARINE IN MIN MICE. THE AVERAGE NUMBER OF POLYPS IN MIN FEMALES DECREASED FROM 58 TO 1, WHEREAS THE AVERAGE POLYP NUMBER REMAINED UNAFFECTED IN MIN MALES POSSIBLY DUE TO DIFFERENTIAL ACTIVITY OF ALDEHYDE OXIDASE. TAKEN TOGETHER, OUR RESULTS SHOW FOR THE FIRST TIME THAT LONG-TERM ORAL ADMINISTRATION OF ZEBULARINE CAUSES A GENDER-SPECIFIC ABROGATION OF INTESTINAL TUMORS WHILE CAUSING A TISSUE-SPECIFIC DNA DEMETHYLATION. IMPORTANTLY, PROLONGED TREATMENT OF MICE WITH EPIGENETIC DRUGS RESULTED IN ONLY MINOR DEVELOPMENTAL AND HISTOLOGIC CHANGES. 2008 4 837 38 CHEMICALLY INDUCED RENAL TUBULE TUMORS IN THE LABORATORY RAT AND MOUSE: REVIEW OF THE NCI/NTP DATABASE AND CATEGORIZATION OF RENAL CARCINOGENS BASED ON MECHANISTIC INFORMATION. THE INCIDENCE OF RENAL TUBULE CARCINOGENESIS IN MALE AND FEMALE RATS OR MICE WITH 69 CHEMICALS FROM THE 513 BIOASSAYS CONDUCTED TO DATE BY THE NCI/NTP HAS BEEN COLLATED, THE CHEMICALS CATEGORIZED, AND THE RELATIONSHIP BETWEEN CARCINOGENESIS AND RENAL TUBULE HYPERPLASIA AND EXACERBATION OF THE SPONTANEOUS, AGE-RELATED RODENT DISEASE CHRONIC PROGRESSIVE NEPHROPATHY (CPN) EXAMINED. WHERE INFORMATION ON MECHANISM OR MODE OF ACTION EXISTS, THE CHEMICALS HAVE BEEN CATEGORIZED BASED ON THEIR ABILITY TO DIRECTLY OR INDIRECTLY INTERACT WITH RENAL DNA, OR ON THEIR ACTIVITY VIA EPIGENETIC PATHWAYS INVOLVING EITHER DIRECT OR INDIRECT CYTOTOXICITY WITH REGENERATIVE HYPERPLASIA, OR EXACERBATION OF CPN. NINE CHEMICALS WERE IDENTIFIED AS DIRECTLY INTERACTING WITH DNA, WITH SIX OF THESE PRODUCING RENAL TUBULE TUMORS AT HIGH INCIDENCE IN RATS OF BOTH SEXES, AND IN SOME CASES ALSO IN MICE. OCHRATOXIN A WAS THE MOST POTENT COMPOUND IN THIS GROUP, PRODUCING A HIGH TUMOR INCIDENCE AT VERY LOW DOSES, OFTEN WITH METASTASIS. THREE CHEMICALS WERE DISCUSSED IN THE CONTEXT OF INDIRECT DNA DAMAGE MEDIATED BY AN OXIDATIVE FREE RADICAL MECHANISM, ONE OF THESE BEING FROM THE NTP DATABASE. A THIRD CATEGORY INCLUDED FOUR CHEMICALS THAT HAD THE POTENTIAL TO CAUSE DNA DAMAGE FOLLOWING CONJUGATION WITH GLUTATHIONE AND SUBSEQUENT ENZYMATIC ACTIVATION TO A REACTIVE SPECIES, USUALLY A THIOL-CONTAINING ENTITY. TWO CHEMICALS WERE ALLOCATED INTO THE CATEGORY INVOLVING A DIRECT CYTOTOXIC ACTION ON THE RENAL TUBULE FOLLOWED BY SUSTAINED COMPENSATORY CELL PROLIFERATION, WHILE NINE WERE INCLUDED IN A GROUP WHERE THE CELL LOSS AND SUSTAINED INCREASE IN RENAL TUBULE CELL TURNOVER WERE DEPENDENT ON LYSOSOMAL ACCUMULATION OF THE MALE RAT-SPECIFIC PROTEIN, ALPHA2MU-GLOBULIN. IN A SIXTH CATEGORY, MORPHOLOGIC EVIDENCE ON TWO CHEMICALS INDICATED THAT THE RENAL TUMORS WERE A CONSEQUENCE OF EXACERBATED CPN. FOR THE REMAINING CHEMICALS, THERE WERE NO PERTINENT DATA ENABLING ASSIGNMENT TO A MECHANISTIC CATEGORY. ACCORDINGLY, THESE CHEMICALS, ACTING THROUGH AN AS YET UNKNOWN MECHANISM, WERE GROUPED AS EITHER BEING ASSOCIATED WITH AN ENHANCEMENT OF CPN (CATEGORY 7, 16 CHEMICALS), OR NOT ASSOCIATED WITH ENHANCED CPN (CATEGORY 8, 4 CHEMICALS). A NINTH CATEGORY DEALT WITH 11 CHEMICALS THAT WERE REGARDED AS PRODUCING INCREASES IN RENAL TUBULE TUMORS THAT DID NOT REACH STATISTICAL SIGNIFICANCE. A 10TH CATEGORY DISCUSSED 6 CHEMICALS THAT INDUCED RENAL TUMORS IN MICE BUT NOT IN RATS, PLUS 8 CHEMICALS THAT PRODUCED A LOW INCIDENCE OF RENAL TUBULE TUMORS IN MICE THAT DID NOT REACH STATISTICAL SIGNIFICANCE. AS MORE MECHANISTIC DATA ARE GENERATED, SOME CHEMICALS WILL INEVITABLY BE PLACED IN DIFFERENT GROUPS, PARTICULARLY THOSE FROM CATEGORIES 7 AND 8. A LARGE NUMBER OF CHEMICALS IN THE SERIES EXACERBATED CPN, BUT THOSE IN CATEGORY 7 ESPECIALLY MAY BE CANDIDATES FOR INCLUSION IN CATEGORY 6 WHEN FURTHER INFORMATION IS GLEANED FROM THE RELEVANT NTP STUDIES. ALSO, NEW DATA ON SPECIFIC CHEMICALS WILL PROBABLY EXPAND CATEGORY 5 AS CYTOTOXICITY AND CELL REGENERATION ARE IDENTIFIED AS OBLIGATORY STEPS IN RENAL CARCINOGENESIS IN MORE CASES. ADDITIONAL CONFIRMATORY OUTCOMES ARISING FROM THIS REVIEW ARE THAT METASTASES FROM RENAL TUBULE TUMORS, WHILE ENCOUNTERED WITH CHEMICALS CAUSING DNA DAMAGE, ARE RARE WITH THOSE ACTING THROUGH AN EPIGENETIC PATHWAY, WITH THE EXCEPTION BEING FUMONISIN B1; THAT MALE RATS AND MICE ARE GENERALLY MORE SUSCEPTIBLE THAN FEMALE RATS AND MICE TO CHEMICAL INDUCTION OF RENAL TUBULE TUMORS; AND THAT A BACKGROUND OF ATYPICAL TUBULE HYPERPLASIA IS A USEFUL INDICATOR REFLECTING A CHEMICALLY ASSOCIATED RENAL TUBULE TUMOR RESPONSE. WITH RESPECT TO RENAL TUBULE TUMORS AND HUMAN RISK ASSESSMENT, CHEMICALS IN CATEGORIES 1 AND 2, AND POSSIBLY 3, WOULD CURRENTLY BE JUDGED BY LINEAR DEFAULT METHODS; CHEMICALS IN CATEGORY 4 (AND PROBABLY SOME IN CATEGORY 3) AS EXHIBITING A THRESHOLD OF ACTIVITY WARRANTING THE BENCHMARK APPROACH; AND THOSE IN CATEGORIES 5 AND 6 AS REPRESENTING MECHANISMS THAT HAVE NO RELEVANCE FOR EXTRAPOLATION TO HUMANS. 2004 5 457 34 APPLYING A MULTISCALE SYSTEMS BIOLOGY APPROACH TO STUDY THE EFFECT OF CHRONIC LOW-DOSE EXPOSURE TO URANIUM IN RAT KIDNEYS. PURPOSE: TO EXAMINE THE EFFECTS OF LOW-DOSE EXPOSURE TO URANIUM WITH A SYSTEMS BIOLOGY APPROACH, A MULTISCALE HIGH-THROUGHPUT MULTI-OMICS ANALYSIS WAS APPLIED WITH A PROTOCOL FOR CHRONIC EXPOSURE TO THE RAT KIDNEY. METHODS: MALE AND FEMALE RATS WERE CONTAMINATED FOR NINE MONTHS THROUGH THEIR DRINKING WATER WITH A NONTOXIC SOLUTION OF URANYL NITRATE. A MULTISCALE APPROACH ENABLED CLINICAL MONITORING ASSOCIATED WITH METABOLOMIC AND TRANSCRIPTOMIC (MRNA AND MICRORNA) ANALYSES. RESULTS: A SEX-INTERACTION EFFECT WAS OBSERVED IN THE KIDNEY, URINE, AND PLASMA METABOLOMES OF CONTAMINATED RATS. MOREOVER, URINE AND KIDNEY METABOLIC PROFILES CORRELATED AND CONFIRMED THAT THE PRIMARY DYSREGULATED METABOLISMS ARE THOSE OF NICOTINATE-NICOTINAMIDE AND OF UNSATURATED FATTY ACID BIOSYNTHESIS. UPSTREAM OF THE METABOLIC PATHWAYS, TRANSCRIPTOMIC PROFILES OF THE KIDNEY REVEAL GENE ACTIVITY FOCUSED ON GENE REGULATION MECHANISMS, CELL SIGNALING, CELL STRUCTURE, DEVELOPMENTAL PROCESSES, AND CELL PROLIFERATION. EXAMINATION OF EPIGENETIC POST-TRANSCRIPTIONAL GENE REGULATION PROCESSES SHOWED SIGNIFICANT DYSREGULATION OF 70 MICRO-RNAS. THE MULTI-OMICS APPROACH HIGHLIGHTED THE ACTIVITIES OF THE CELLS' BIOLOGICAL PROCESSES ON MULTIPLE SCALES THROUGH ANALYSIS OF GENE EXPRESSION, CONFIRMED BY CHANGES OBSERVED IN THE METABOLOME. CONCLUSION: OUR RESULTS SHOWED CHANGES IN MULTI-OMIC PROFILES OF RATS EXPOSED TO LOW DOSES OF URANIUM CONTAMINATION, COMPARED WITH CONTROLS. THESE CHANGES INVOLVED GENE EXPRESSION AS WELL AS MODIFICATIONS IN THE TRANSCRIPTOME AND THE METABOLOME. THE METABOLOMIC PROFILE CONFIRMED THAT THE MAIN MOLECULAR TARGETS OF URANIUM IN KIDNEY CELLS ARE THE METABOLISM OF NICOTINATE-NICOTINAMIDE AND THE BIOSYNTHESIS OF UNSATURATED FATTY ACIDS. ADDITIONALLY, GENE EXPRESSION ANALYSIS SHOWED THAT THE METABOLISM OF FATTY ACIDS IS TARGETED BY PROCESSES ASSOCIATED WITH CELL FUNCTION. THESE RESULTS DEMONSTRATE THAT MULTISCALE SYSTEMS BIOLOGY IS USEFUL IN ELUCIDATING THE MOST DISCRIMINATIVE PATHWAYS FROM GENOMIC TO METABOLOMIC LEVELS FOR ASSESSING THE BIOLOGICAL IMPACT OF THIS LOW-LEVEL ENVIRONMENTAL EXPOSURE, I.E. THE EXPOSOME. 2019 6 4224 25 METHYLATION CHANGES IN MUSCLE AND LIVER TISSUES OF MALE AND FEMALE MICE EXPOSED TO ACUTE AND CHRONIC LOW-DOSE X-RAY-IRRADIATION. THE BIOLOGICAL AND GENETIC EFFECTS OF CHRONIC LOW-DOSE RADIATION (LDR) EXPOSURE AND ITS RELATIONSHIP TO CARCINOGENESIS HAVE RECEIVED A LOT OF ATTENTION IN THE RECENT YEARS. FOR EXAMPLE, RADIATION-INDUCED GENOME INSTABILITY, WHICH IS THOUGHT TO BE A PRECURSOR OF TUMOROGENESIS, WAS SHOWN TO HAVE A TRANSGENERATIONAL NATURE. THIS INDICATES A POSSIBLE INVOLVEMENT OF EPIGENETIC MECHANISMS IN LDR-INDUCED GENOME INSTABILITY. GENOMIC DNA METHYLATION IS ONE OF THE MOST IMPORTANT EPIGENETIC MECHANISMS. EXISTING DATA ON RADIATION EFFECTS ON DNA METHYLATION PATTERNS IS LIMITED, AND NO ONE HAS SPECIFICALLY STUDIED THE EFFECTS OF THE LDR. WE REPORT THE FIRST STUDY OF THE EFFECTS OF WHOLE-BODY LDR EXPOSURE ON GLOBAL GENOME METHYLATION IN MUSCLE AND LIVER TISSUES OF MALE AND FEMALE MICE. IN PARALLEL, WE EVALUATED CHANGES IN PROMOTER METHYLATION AND EXPRESSION OF THE TUMOR SUPPRESSOR GENE P16(INKA) AND DNA REPAIR GENE O(6)-METHYLGUANINE-DNA METHYLTRANSFERASE (MGMT). WE OBSERVED DIFFERENT PATTERNS OF RADIATION-INDUCED GLOBAL GENOME DNA METHYLATION IN THE LIVER AND MUSCLE OF EXPOSED MALES AND FEMALES. WE ALSO FOUND SEX AND TISSUE-SPECIFIC DIFFERENCES IN P16(INKA) PROMOTER METHYLATION UPON LDR EXPOSURE. IN MALE LIVER TISSUE, P16(INKA) PROMOTER METHYLATION WAS MORE PRONOUNCED THAN IN FEMALE TISSUE. IN CONTRAST, NO SIGNIFICANT RADIATION-INDUCED CHANGES IN P16(INKA) PROMOTER METHYLATION WERE NOTED IN THE MUSCLE TISSUE OF EXPOSED MALES AND FEMALES. RADIATION ALSO DID NOT SIGNIFICANTLY AFFECT METHYLATION STATUS OF MGMT PROMOTER. WE ALSO OBSERVED SUBSTANTIAL SEX DIFFERENCES IN ACUTE AND CHRONIC RADIATION-INDUCED EXPRESSION OF P16(INKA) AND MGMT GENES. ANOTHER IMPORTANT OUTCOME OF OUR STUDY WAS THE FACT THAT CHRONIC LOW-DOSE RADIATION EXPOSURE PROVED TO BE A MORE POTENT INDUCER OF EPIGENETIC EFFECTS THAN THE ACUTE EXPOSURE. THIS SUPPORTS PREVIOUS FINDINGS THAT CHRONIC EXPOSURE LEADS TO GREATER GENOME DESTABILIZATION THAN ACUTE EXPOSURE. 2004 7 126 41 A TOXICOGENOMICS APPROACH TO IDENTIFY NEW PLAUSIBLE EPIGENETIC MECHANISMS OF OCHRATOXIN A CARCINOGENICITY IN RAT. OCHRATOXIN A (OTA) IS A MYCOTOXIN OCCURRING NATURALLY IN A WIDE RANGE OF FOOD COMMODITIES. IN ANIMALS, IT HAS BEEN SHOWN TO CAUSE A VARIETY OF ADVERSE EFFECTS, NEPHROCARCINOGENICITY BEING THE MOST PROMINENT. BECAUSE OF ITS HIGH TOXIC POTENCY AND THE CONTINUOUS EXPOSURE OF THE HUMAN POPULATION, OTA HAS RAISED PUBLIC HEALTH CONCERNS. THERE IS SIGNIFICANT DEBATE ON HOW TO USE THE RAT CARCINOGENICITY DATA TO ASSESS THE POTENTIAL RISK TO HUMANS. IN THIS CONTEXT, THE QUESTION OF THE MECHANISM OF ACTION OF OTA APPEARS OF KEY IMPORTANCE AND WAS STUDIED THROUGH THE APPLICATION OF A TOXICOGENOMICS APPROACH. MALE FISCHER RATS WERE FED OTA FOR UP TO 2 YEARS. RENAL TUMORS WERE DISCOVERED DURING THE LAST 6 MONTHS OF THE STUDY. THE TOTAL TUMOR INCIDENCE REACHED 25% AT THE END OF THE STUDY. GENE EXPRESSION PROFILE WAS ANALYZED IN GROUPS OF ANIMALS TAKEN IN INTERVALS FROM 7 DAYS TO 12 MONTHS. TISSUE-SPECIFIC RESPONSES WERE OBSERVED IN KIDNEY VERSUS LIVER. FOR SELECTED GENES, MICROARRAY DATA WERE CONFIRMED AT BOTH MRNA AND PROTEIN LEVELS. IN KIDNEY, SEVERAL GENES KNOWN AS MARKERS OF KIDNEY INJURY AND CELL REGENERATION WERE SIGNIFICANTLY MODULATED BY OTA. THE EXPRESSION OF GENES KNOWN TO BE INVOLVED IN DNA SYNTHESIS AND REPAIR, OR GENES INDUCED AS A RESULT OF DNA DAMAGE, WAS ONLY MARGINALLY MODULATED. VERY LITTLE OR NO EFFECT WAS FOUND AMONGST GENES ASSOCIATED WITH APOPTOSIS. ALTERATIONS OF GENE EXPRESSION INDICATING EFFECTS ON CALCIUM HOMEOSTASIS AND A DISRUPTION OF PATHWAYS REGULATED BY THE TRANSCRIPTION FACTORS HEPATOCYTE NUCLEAR FACTOR 4 ALPHA (HNF4ALPHA) AND NUCLEAR FACTOR-ERYTHROID 2-RELATED FACTOR 2 (NRF2) WERE OBSERVED IN THE KIDNEY BUT NOT IN THE LIVER. PREVIOUS DATA HAVE SUGGESTED THAT A REDUCTION IN HNF4ALPHA MAY BE ASSOCIATED WITH NEPHROCARCINOGENICITY. MANY NRF2-REGULATED GENES ARE INVOLVED IN CHEMICAL DETOXICATION AND ANTIOXIDANT DEFENSE. THE DEPLETION OF THESE GENES IS LIKELY TO IMPAIR THE DEFENSE POTENTIAL OF THE CELLS, RESULTING IN CHRONIC ELEVATION OF OXIDATIVE STRESS IN THE KIDNEY. THE INHIBITION OF DEFENSE MECHANISM APPEARS AS A HIGHLY PLAUSIBLE NEW MECHANISM, WHICH COULD CONTRIBUTE TO OTA CARCINOGENICITY. 2006 8 818 22 CHARACTERISTICS OF THE SPECTRUM OF PROLIFERATIVE LESIONS OBSERVED IN THE KIDNEY AND URINARY BLADDER OF FISCHER 344 RATS AND B6C3F1 MICE. MANY RODENT RENAL AND BLADDER CARCINOGENS RELY UPON EPIGENETIC MECHANISMS OF CARCINOGENESIS; SUCH MECHANISMS ARE LIKELY TO INFLUENCE THE SPECTRUM OF URINARY TRACT TUMORS OBSERVED IN CONTROL AND TREATED ANIMALS. THIS IS REFLECTED IN SEVERAL FEATURES OF CHEMICALLY INDUCED RODENT URINARY TRACT NEOPLASMS, INCLUDING A LOW OVERALL TUMOR INCIDENCE, AN INCREASED PREVALENCE OF URINARY TRACT TUMORS IN RATS COMPARED TO MICE AND MALES COMPARED TO FEMALES, THE TENDENCY FOR EPITHELIAL TUMORS TO PREDOMINATE OVER NONEPITHELIAL TYPES, AND DEMONSTRATED LINKS TO CHRONIC PROGRESSIVE NEPHROPATHY AND UROLITHIASIS. SUCH TENDENCIES ARE ALSO CHARACTERISTIC OF SPONTANEOUS URINARY TRACT TUMORS IN RODENTS. DATA TO SUPPORT THESE OBSERVATIONS CAN BE DERIVED FROM LARGE HISTORICAL DATABASES SUCH AS THE TOXICOLOGY DATA MANAGEMENT SYSTEM, MAINTAINED BY NATIONAL TOXICOLOGY PROGRAM. 2002 9 4121 35 MECHANISMS OF CHEMICALLY INDUCED RENAL CARCINOGENESIS IN THE LABORATORY RODENT. LABORATORY STUDIES WITH CLASSICAL RENAL CARCINOGENS IN THE RAT AND MOUSE, AS WELL AS RESEARCH INVESTIGATION WITH SOME OF THE CHEMICALS PROVING POSITIVE FOR THE KIDNEY IN NATIONAL TOXICOLOGY PROGRAM CARCINOGENICITY BIOASSAYS, HAVE DEMONSTRATED THE EXISTENCE OF A RANGE OF DIVERSE MECHANISMS UNDERLYING RODENT KIDNEY CARCINOGENESIS. THE CLASSICAL CARCINOGENS USED AS EXPERIMENTAL MODELS FOR STUDYING RENAL TUMOR PATHOGENESIS, SUCH AS THE NITROSAMINES, ARE GENOTOXIC AND INTERACT DIRECTLY WITH DNA, FORMING DNA ADDUCTS WITH MUTAGENIC POTENTIAL. IN CONTRAST, POTASSIUM BROMATE AND FERRIC NITRILOTRIACETATE (FE-NTA), ALSO EFFECTIVE RENAL CARCINOGENS, APPEAR TO CAUSE INDIRECT DAMAGE TO DNA MEDIATED BY OXIDATIVE STRESS. A NUMBER OF NONGENOTOXIC CHEMICALS ARE ASSOCIATED WITH EPIGENETIC RENAL TUMOR INDUCTION IN RODENTS, AND THE ACTIVITY OF THESE TENDS TO INVOLVE PROLONGED STIMULATION OF CELL PROLIFERATION THROUGHOUT THE DURATION OF EXPOSURE. THIS MODE OF ACTION REFLECTS A SUSTAINED REGENERATIVE RESPONSE, EITHER DUE TO DIRECT CHEMICAL TOXICITY TO THE TUBULE CELLS, AS WITH CHLOROFORM, OR TO INDIRECT CYTOTOXICITY ASSOCIATED WITH LYSOSOMAL OVERLOAD, AS IN ALPHA2U-GLOBULIN ACCUMULATION IN MALE RATS RESULTING FROM THE ADMINISTRATION OF SUCH CHEMICALS AS D-LIMONENE AND TETRACHLOROETHYLENE. THE HISTOPATHOLOGIC NATURE OF HYDROQUINONE RENAL CARCINOGENESIS SUGGESTS THAT AN ADDITIONAL EPIGENETIC PATHWAY TO RENAL TUBULE TUMOR FORMATION IN RATS MAY BE THROUGH CHEMICAL-MEDIATED EXACERBATION OF, AND INTERACTION WITH, THE AGE-RELATED SPONTANEOUS RENAL DISEASE, CHRONIC PROGRESSIVE NEPHROPATHY. THESE VARIOUS MECHANISTIC PATHWAYS HAVE IMPLICATIONS FOR THE NATURE OF THE INDUCED CANCER PROCESS WITH RESPECT TO TUMOR INCIDENCE, LATENCY, MALIGNANCY, AND SEX PREDISPOSITION. 1998 10 2297 20 EPIGENETIC REGULATION OF ACUTE INFLAMMATORY PAIN. ACUTE PAIN IS ASSOCIATED WITH TISSUE DAMAGE, WHICH RESULTS IN THE RELEASE OF INFLAMMATORY MEDIATORS. RECENT STUDIES POINT TO THE INVOLVEMENT OF EPIGENETIC MECHANISMS (DNA METHYLATION) IN THE DEVELOPMENT OF PAIN. WE HAVE FOUND THAT DURING ACUTE INFLAMMATORY PAIN INDUCED BY THE APPLICATION OF 10% MUSTARD OIL ON THE TONGUES OF RATS, LEVELS OF DNMT3A AND 3B WERE ELEVATED MARKEDLY (36 AND 42 % RESPECTIVELY), WHEREAS THE LEVEL OF DNMT1 WAS NOT CHANGED SIGNIFICANTLY. PREVIOUS INJECTION OF XEFOCAM WITH 0,4 MG/KG DOSE DECREASED LEVELS OF DNMT3A AND 3B (25 AND 24% RESPECTIVELY). THE LEVEL OF DNMT1 WAS NOT CHANGED SIGNIFICANTLY COMPARED TO THE CONTROL GROUP. THE FINDINGS SUPPORT THE IDEA THAT INHIBITORS OF DNA-METHYLTRANSFERASES COULD BE USEFUL FOR PAIN MANAGEMENT. OUR DATA SUGGEST THAT NSAIDS (ALONE OR IN COMBINATION WITH DNMT INHIBITORS) MAY BE PROPOSED AS POSSIBLE EPIGENETIC REGULATORY AGENTS, WHICH MAY PLAY A ROLE IN EPIGENETIC MECHANISMS INDIRECTLY THROUGH ALTERING THE ACTIVITY OF INFLAMMATORY MEDIATORS INVOLVED IN PAIN DEVELOPMENT. 2014 11 1511 31 DNA METHYLATION AND POTENTIAL MULTIGENERATIONAL EPIGENETIC EFFECTS LINKED TO URANIUM CHRONIC LOW-DOSE EXPOSURE IN GONADS OF MALES AND FEMALES RATS. INTRODUCTION: AN INCREASED HEALTH PROBLEM IN INDUSTRIALISED COUNTRIES IS THE CONTEMPORARY CONCERN OF PUBLIC AND SCIENTIFIC COMMUNITY AS WELL. THIS HAS BEEN ATTRIBUTED IN PART TO ACCUMULATED ENVIRONMENTAL POLLUTANTS ESPECIALLY RADIOACTIVE SUBSTANCES AND THE USE OF NUCLEAR POWER PLANTS WORLDWIDE. HOWEVER, THE OUTCOME OF CHRONIC EXPOSURE TO LOW DOSES OF A RADIONUCLIDE SUCH AS URANIUM REMAINS UNKNOWN. RECENTLY, A PARADIGM SHIFT IN THE PERCEPTION OF RISK OF RADIOTOXICOLOGY HAS EMERGED THROUGH INVESTIGATING THE POSSIBILITY OF TRANSMISSION OF BIOLOGICAL EFFECTS OVER GENERATIONS, IN PARTICULAR BY EPIGENETIC PATHWAYS. THESE PROCESSES ARE KNOWN FOR THEIR CRUCIAL ROLES ASSOCIATED WITH THE DEVELOPMENT OF SEVERAL DISEASES. OBJECTIVE: THE CURRENT WORK INVESTIGATES THE EPIGENETIC EFFECT OF CHRONIC EXPOSURE TO LOW DOSES OF URANIUM AND ITS INHERITANCE ACROSS GENERATIONS. MATERIALS AND METHODS TO TEST THIS PROPOSITION, A RODENT MULTIGENERATIONAL MODEL, MALES AND FEMALES, WERE EXPOSED TO A NON-TOXIC CONCENTRATION OF URANIUM (40MGL(-1) DRINKING WATER) FOR NINE MONTHS. THE URANIUM EFFECTS ON WERE EVALUATED OVER THREE GENERATIONS (F0, F1 AND F2) BY ANALYSING THE DNA METHYLATION PROFILE AND DNMT GENES EXPRESSION IN OVARIES AND TESTES TISSUES. RESULTS: HERE WE REPORT A SIGNIFICANT HYPERMETHYLATION OF TESTES DNA (P <0.005) WHEREAS OVARIES SHOWED HYPOMETHYLATED DNA (P <0.005). INTERESTINGLY, THIS DNA METHYLATION PROFILE WAS SIGNIFICANTLY MAINTAINED ACROSS GENERATIONS F0, F1 AND F2. FURTHERMORE, QPCR RESULTS OF BOTH TISSUES IMPLY A SIGNIFICANT CHANGE IN THE EXPRESSION OF DNA METHYLTRANSFERASE GENES (DNMT 1 AND DNMT3A/B) AS WELL. CONCLUSION: ALTOGETHER, OUR WORK DEMONSTRATES FOR THE FIRST TIME A SEX-DEPENDANCE AND INHERITANCE OF EPIGENETIC MARKS, DNA METHYLATION, AS A BIOLOGICAL RESPONSE TO THE EXPOSURE TO LOW DOSES OF URANIUM. HOWEVER, IT IS NOT CLEAR WHICH TYPE OF REPRODUCTIVE CELL TYPE IS MORE RESPONSIVE IN THIS CONTEXT. 2018 12 3726 28 INHIBITION OF HISTONE METHYLTRANSFERASE EZH2 SUPPRESSES ENDOMETRIOTIC VESICLE DEVELOPMENT IN A RAT MODEL OF ENDOMETRIOSIS. ENDOMETRIOSIS IS A PAINFUL GYNECOLOGICAL DISEASE WITH NO CURE AND LIMITED THERAPEUTIC OPTIONS. IT HAS BEEN HYPOTHESIZED THAT EPIGENETIC DRUGS CAN BE USED AS A NONHORMONAL TREATMENT FOR ENDOMETRIOSIS. THIS STUDY WAS CONDUCTED TO STUDY THE EFFICACY OF AN INHIBITOR OF THE HISTONE METHYLTRANSFERASE EZH2 USING AN ESTABLISHED RAT MODEL OF ENDOMETRIOSIS. WE HYPOTHESIZED THAT TREATMENT WILL BLOCK OR REDUCE THE NUMBER OF ENDOMETRIOTIC VESICLES IN THIS MODEL. WE CONDUCTED A PRECLINICAL DRUG STUDY IN FEMALE RATS WITH EXPERIMENTAL ENDOMETRIOSIS (UTERINE TISSUE TRANSPLANTED NEXT TO THE INTESTINAL MESENTERY) OR CONTROL SHAM (SUTURES ONLY). RATS WITH ENDOMETRIOSIS OR SHAM SURGERY RECEIVED EITHER TREATMENT WITH EZH2 INHIBITOR (5 MG/KG OR 10 MG/KG) OR VEHICLE (0.1%, 67% DMSO) EVERY OTHER DAY DURING 4 WEEKS. AFTER TREATMENT COMPLETION, THE NUMBER, AREA, VOLUME, AND WEIGHT OF VESICLES WERE EVALUATED. RT [2] PROFILER ARRAYS FOR NEUROPATHIC AND INFLAMMATION, EPITHELIAL TO MESENCHYMAL TRANSITION, INFLAMMATORY RESPONSE, AND AUTOIMMUNITY PATHWAYS WERE USED TO EXAMINE GENE EXPRESSION CHANGES IN THE VESICLES THAT DEVELOPED. TREATMENT WITH EZH2 INHIBITOR (10 MG/KG) SUPPRESSED THE DEVELOPMENT OF VESICLES, BY SIGNIFICANTLY DECREASING THE TOTAL VESICLE NUMBER, AREA, VOLUME, AND WEIGHT. IN ADDITION, EZH2 INHIBITION SIGNIFICANTLY INCREASED THE EXPRESSION OF CACNA1B AND FKBP1A GENES, INVOLVED IN PAIN AND PROLIFERATION, RESPECTIVELY. EZH2 INHIBITION SUPPRESSES THE GROWTH OF VESICLES WITHOUT APPARENT DETRIMENTAL EFFECTS TO OTHER ORGANS. TREATMENT WITH THIS EPIGENETIC INHIBITOR LEADS TO UPREGULATION OF A LIMITED NUMBER OF GENES RELATED TO ENDOMETRIOSIS-RELEVANT PATHWAYS. IN CONCLUSION, THESE DATA SUPPORT FOLLOW-UP STUDIES TO EVALUATE ITS POTENTIAL AS A THERAPEUTIC APPROACH FOR ENDOMETRIOSIS. 2020 13 904 28 CHRONIC EXPOSURE TO CADMIUM INDUCES DIFFERENTIAL METHYLATION IN MICE SPERMATOZOA. CADMIUM EXPOSURE IS UBIQUITOUS AND HAS BEEN LINKED TO DISEASES INCLUDING CANCERS AND REPRODUCTIVE DEFECTS. SINCE CADMIUM IS NONMUTAGENIC, IT IS THOUGHT TO EXERT ITS GENE DYSREGULATORY EFFECTS THROUGH EPIGENETIC REPROGRAMMING. SEVERAL STUDIES HAVE IMPLICATED GERMLINE EXPOSURE TO CADMIUM IN DEVELOPMENTAL REPROGRAMMING. HOWEVER, MOST OF THESE STUDIES HAVE FOCUSED ON MATERNAL EXPOSURE, WHILE THE IMPACT ON SPERM FERTILITY AND DISEASE SUSCEPTIBILITY HAS RECEIVED LESS ATTENTION. IN THIS STUDY, WE USED REDUCED REPRESENTATION BISULFITE SEQUENCING TO COMPREHENSIVELY INVESTIGATE THE IMPACT OF CHRONIC CADMIUM EXPOSURE ON MOUSE SPERMATOZOA DNA METHYLATION. ADULT MALE C57BL/J6 MICE WERE PROVIDED WATER WITH OR WITHOUT CADMIUM CHLORIDE FOR 9 WEEKS. SPERM, TESTES, LIVER, AND KIDNEY TISSUES WERE COLLECTED AT THE END OF THE TREATMENT PERIOD. CADMIUM EXPOSURE WAS CONFIRMED THROUGH GENE EXPRESSION ANALYSIS OF METALLOTHIONEIN-1 AND 2, 2 WELL-KNOWN CADMIUM-INDUCED GENES. ANALYSIS OF SPERM DNA METHYLATION CHANGES REVEALED 1788 DIFFERENTIALLY METHYLATED SITES PRESENT AT REGULATORY REGIONS IN SPERM OF MICE EXPOSED TO CADMIUM COMPARED WITH VEHICLE (CONTROL) MICE. FURTHERMORE, MOST OF THESE DIFFERENTIAL METHYLATION CHANGES POSITIVELY CORRELATED WITH CHANGES IN GENE EXPRESSION AT BOTH THE TRANSCRIPTION INITIATION STAGE AS WELL AS THE SPLICING LEVELS. INTERESTINGLY, THE GENES TARGETED BY CADMIUM EXPOSURE ARE INVOLVED IN SEVERAL CRITICAL DEVELOPMENTAL PROCESSES. OUR RESULTS PRESENT A COMPREHENSIVE ANALYSIS OF THE SPERM METHYLOME IN RESPONSE TO CHRONIC CADMIUM EXPOSURE. THESE DATA, THEREFORE, HIGHLIGHT A FOUNDATIONAL FRAMEWORK TO STUDY GENE EXPRESSION PATTERNS THAT MAY AFFECT FERTILITY IN THE EXPOSED INDIVIDUAL AS WELL AS THEIR OFFSPRING, THROUGH PATERNAL INHERITANCE. 2021 14 1655 23 DOSE-DEPENDENCE, SEX- AND TISSUE-SPECIFICITY, AND PERSISTENCE OF RADIATION-INDUCED GENOMIC DNA METHYLATION CHANGES. RADIATION IS A WELL-KNOWN GENOTOXIC AGENT AND HUMAN CARCINOGEN THAT GIVES RISE TO A VARIETY OF LONG-TERM EFFECTS. ITS DETRIMENTAL INFLUENCE ON CELLULAR FUNCTION IS ACTIVELY STUDIED NOWADAYS. ONE OF THE MOST ANALYZED, YET LEAST UNDERSTOOD LONG-TERM EFFECTS OF IONIZING RADIATION IS TRANSGENERATIONAL GENOMIC INSTABILITY. THE INHERITANCE OF GENOMIC INSTABILITY SUGGESTS THE POSSIBLE INVOLVEMENT OF EPIGENETIC MECHANISMS, SUCH AS CHANGES OF THE METHYLATION OF CYTOSINE RESIDUES LOCATED WITHIN CPG DINUCLEOTIDES. IN THE CURRENT STUDY WE EVALUATED THE DOSE-DEPENDENCE OF THE RADIATION-INDUCED GLOBAL GENOME DNA METHYLATION CHANGES. WE ALSO ANALYZED THE EFFECTS OF ACUTE AND CHRONIC HIGH DOSE (5GY) EXPOSURE ON DNA METHYLATION IN LIVER, SPLEEN, AND LUNG TISSUES OF MALE AND FEMALE MICE AND EVALUATED THE POSSIBLE PERSISTENCE OF THE RADIATION-INDUCED DNA METHYLATION CHANGES. HERE WE REPORT THAT RADIATION-INDUCED DNA METHYLATION CHANGES WERE SEX- AND TISSUE-SPECIFIC, DOSE-DEPENDENT, AND PERSISTENT. IN PARALLEL WE HAVE STUDIED THE LEVELS OF DNA DAMAGE IN THE EXPOSED TISSUES. BASED ON THE CORRELATION BETWEEN THE LEVELS OF DNA METHYLATION AND DNA DAMAGE WE PROPOSE THAT RADIATION-INDUCED GLOBAL GENOME DNA HYPOMETHYLATION IS DNA REPAIR-RELATED. 2004 15 6564 27 TRANSIENT EXPOSURE TO ELEVATED GLUCOSE LEVELS CAUSES PERSISTENT CHANGES IN DERMAL MICROVASCULAR ENDOTHELIAL CELL RESPONSES TO INJURY. BACKGROUND: THE PURPOSE OF THIS STUDY WAS TO DETERMINE WHETHER ELEVATED GLUCOSE CAN INDUCE A DERMAL MICROVASCULAR ENDOTHELIAL CELL METABOLIC MEMORY, THUS AFFECTING ANGIOGENESIS IN THE REPAIR PROCESS OF MAMMALIAN CUTANEOUS WOUND. WE HYPOTHESIZED THAT TRANSIENT ELEVATED GLUCOSE LEVELS CAUSE SUSTAINED ALTERATION OF ENDOTHELIAL CELL RESPONSES TO INJURY AND PERSISTENT EPIGENETIC CHANGES IN GENE EXPRESSION. METHODS: HUMAN DERMAL MICROVASCULAR ENDOTHELIAL CELLS WERE EXPOSED TO EXPERIMENTAL CONDITIONS WITH OR WITHOUT 30 MM D-GLUCOSE. THE CONTROL GROUP WAS MAINTAINED AT 5 MM D-GLUCOSE; WHILE IN THE TRANSIENT GLUCOSE GROUP, AFTER BEING EXPOSED TO 30 MM D-GLUCOSE FOR TWO DAYS, THEN BEING PUT UNDER THE CONTROL CONDITIONS DURING THE EXPERIMENT. BESIDES, IN THE WHOLE PROCESS OF THE EXPERIMENT, THE CHRONIC GLUCOSE GROUP WAS KEPT IN THE CONDITION WITH 30 MM D-GLUCOSE. PROLIFERATION, MIGRATION, TUBE FORMATION, GENE EXPRESSION AND HISTONE METHYLATION WERE ASSESSED FOR INDIVIDUAL CONDITIONS. RESULTS: TRANSIENT ELEVATED GLUCOSE CAUSED SUSTAINED EFFECTS ON ENDOTHELIAL CELL MIGRATION, TUBE FORMATION AND TIMP3 GENE EXPRESSION. THE EFFECTS ON TIMP3 EXPRESSION WERE ASSOCIATED WITH PERSISTENT CHANGES IN HISTONE MODIFICATION AT THE 5' END OF THE TIMP3 GENE, SUGGESTING AN EPIGENETIC EFFECT. CONCLUSIONS: HYPERGLYCEMIA INDUCED METABOLIC MEMORY COULD PROMOTE THE REGULATION OF TIMP3, AND IT CAN BE USED AS A POSSIBLE INNOVATIVE MOLECULAR TARGET FOR THERAPEUTIC INTERVENTION IN THE TREATMENT OF CHRONIC NON-HEALING DIABETIC WOUNDS. 2021 16 894 31 CHRONIC ETHANOL FEEDING ALTERS HEPATOCYTE MEMORY WHICH IS NOT ALTERED BY ACUTE FEEDING. BACKGROUND: GENE EXPRESSION CHANGES IN THE LIVER AFTER ACUTE BINGE DRINKING MAY DIFFER FROM THE CHANGES SEEN IN CHRONIC ETHANOL FEEDING IN THE RAT. THE CHANGES IN GENE EXPRESSION AFTER CHRONIC ETHANOL FEEDING MAY SENSITIZE THE LIVER TO ALCOHOL-INDUCED LIVER DAMAGE, WHICH IS NOT SEEN AFTER ACUTE BINGE DRINKING. METHODS: TO TEST THIS HYPOTHESIS, GENE MICROARRAY ANALYSIS WAS PERFORMED ON THE LIVERS OF RATS (N = 3) FED AN ACUTE BINGE DOSE OF ETHANOL (6 G/KG BODY WT) AND KILLED AT 3 AND 12 HOURS AFTER ETHANOL BY GAVAGE. THE GENE MICROARRAYS WERE COMPARED WITH THOSE MADE ON THE LIVER OF RATS FROM A PREVIOUS STUDY, IN WHICH THE RATS WERE FED ETHANOL BY INTRAGASTRIC TUBE FOR 1 MONTH (36% OF CALORIES DERIVED FROM ETHANOL). RESULTS: MICROARRAY ANALYSIS DATA VARIED BETWEEN THE ACUTE AND CHRONIC MODELS IN SEVERAL IMPORTANT RESPECTS. GROWTH FACTORS INCREASED MAINLY IN THE CHRONIC ALCOHOL FED RAT. CHANGES IN ENZYMES INVOLVED IN OXIDATIVE STRESS WERE NOTED ONLY WITH CHRONIC ETHANOL FEEDING. GENE EXPRESSION OF FAT METABOLISM WAS INCREASED ONLY WITH CHRONIC ETHANOL FEEDING. MOST IMPORTANTLY, EPIGENETIC RELATED ENZYMES AND ACETYLATION AND METHYLATION OF HISTONES CHANGED ONLY AFTER CHRONIC ETHANOL FEEDING. CONCLUSIONS: THE RESULTS SUPPORT THE CONCEPT THAT CHRONIC ETHANOL INGESTION INDUCES ALTERED GENE EXPRESSION AS A RESULT OF CHANGES IN EPIGENETIC MECHANISMS, WHERE ACETYLATION AND METHYLATION OF HISTONES WERE ALTERED. 2009 17 5189 30 PRENATAL ARSENIC EXPOSURE INDUCES IMMUNOMETABOLIC ALTERATION AND RENAL INJURY IN RATS. ARSENIC (AS) EXPOSURE IS PROGRESSIVELY ASSOCIATED WITH CHRONIC KIDNEY DISEASE (CKD), A LEADING PUBLIC HEALTH CONCERN PRESENT WORLDWIDE. THE ADVERSE EFFECT OF AS EXPOSURE ON THE KIDNEYS OF PEOPLE LIVING IN AS ENDEMIC AREAS HAVE NOT BEEN EXTENSIVELY STUDIED. FURTHERMORE, THE IMPACT OF ONLY PRENATAL EXPOSURE TO AS ON THE PROGRESSION OF CKD ALSO HAS NOT BEEN FULLY CHARACTERIZED. IN THE PRESENT STUDY, WE EXAMINED THE EFFECT OF PRENATAL EXPOSURE TO LOW DOSES OF AS 0.04 AND 0.4 MG/KG BODY WEIGHT (0.04 AND 0.4 PPM, RESPECTIVELY) ON THE PROGRESSION OF CKD IN MALE OFFSPRING USING A WISTAR RAT MODEL. INTERESTINGLY, ONLY PRENATAL AS EXPOSURE WAS SUFFICIENT TO ELEVATE THE EXPRESSION OF PROFIBROTIC (TGF-BETA1) AND PROINFLAMMATORY (IL-1ALPHA, MIP-2ALPHA, RANTES, AND TNF-ALPHA) CYTOKINES AT 2-DAY, 12- AND 38-WEEK TIME POINTS IN THE EXPOSED PROGENY. FURTHER, ALTERATION IN ADIPOGENIC FACTORS (GHRELIN, LEPTIN, AND GLUCAGON) WAS ALSO OBSERVED IN 12- AND 38-WEEK OLD MALE OFFSPRING PRENATALLY EXPOSED TO AS. AN ALTERED LEVEL OF THESE FACTORS COINCIDES WITH IMPAIRED GLUCOSE METABOLISM AND HOMEOSTASIS ACCOMPANIED BY PROGRESSIVE KIDNEY DAMAGE. WE OBSERVED A SIGNIFICANT INCREASE IN THE DEPOSITION OF EXTRACELLULAR MATRIX COMPONENTS AND GLOMERULAR AND TUBULAR DAMAGE IN THE KIDNEYS OF 38-WEEK-OLD MALE OFFSPRING PRENATALLY EXPOSED TO AS. FURTHERMORE, THE OVEREXPRESSION OF TGF-BETA1 IN KIDNEYS CORRESPONDS WITH HYPERMETHYLATION OF THE TGF-BETA1 GENE-BODY, INDICATING A POSSIBLE INVOLVEMENT OF PRENATAL AS EXPOSURE-DRIVEN EPIGENETIC MODULATIONS OF TGF-BETA1 EXPRESSION. OUR STUDY PROVIDES EVIDENCE THAT PRENATAL AS EXPOSURE TO MALES CAN ADVERSELY AFFECT THE IMMUNOMETABOLISM OF OFFSPRING WHICH CAN PROMOTE KIDNEY DAMAGE LATER IN LIFE. 2022 18 2683 26 EVALUATION OF THE IMPACT OF S-ADENOSYLMETHIONINE-DEPENDENT METHYLTRANSFERASE INHIBITOR, 3-DEAZANEPLANOCIN A, ON TISSUE INJURY AND COGNITIVE FUNCTION IN MICE. CANCER PATIENTS DISPLAY COGNITIVE IMPAIRMENT DUE, AT LEAST PARTLY, TO THE TREATMENTS. ADDITIONALLY, CHEMOTHERAPEUTIC TREATMENTS CAN LEAD TO ORGAN INJURY, LIMITING THEIR USE, AND ARE LIKELY TO HAVE NEGATIVE IMPACTS ON PATIENTS' QUALITY OF LIFE. THE AIM OF THIS STUDY WAS TO INVESTIGATE THE TOXICITY OF 3-DEAZANEPLANOCIN A (DZNEP) ON SEVERAL TISSUES AND ORGANS, AS WELL AS ON COGNITIVE FUNCTIONS. DZNEP IS AN INHIBITOR OF S-ADENOSYLMETHIONINE-DEPENDENT METHYLTRANSFERASE (IN PARTICULAR OF THE HISTONE METHYLTRANSFERASE EZH2) WHICH SHOWED ANTITUMORAL FUNCTIONS IN PRECLINICAL TRIALS BUT WHOSE EFFECTS ON BEHAVIOR AND ON ORGANS (SIDE EFFECTS) ARE NOT KNOWN. CHRONIC INJECTIONS OF DZNEP WERE PERFORMED INTRAPERITONEALLY IN MALE NMRI MICE (2 MG/KG; I.P.; THREE TIMES PER WEEK) DURING 8 WEEKS. A FOLLOW-UP OF BODY WEIGHT WAS ASSESSED DURING ALL EXPERIMENTS. HISTOLOGICAL ANALYSIS WERE PERFORMED ON SEVERAL ORGANS. EZH2 EXPRESSION AND H3K27ME3 WERE ASSAYED BY WESTERN-BLOT. SEVERAL BEHAVIORAL TESTS WERE PERFORMED DURING TREATMENT AND 2 WEEKS AFTER. A PARTICULAR FOCUS WAS MADE ON SPONTANEOUS LOCOMOTOR ACTIVITY, COGNITIVE FUNCTIONS (SPONTANEOUS ALTERNATION AND RECOGNITION MEMORY), AND ANXIETY- AND DEPRESSION-RELATED BEHAVIOR. HEMATOLOGICAL MODIFICATIONS WERE ALSO ASSESSED. CHRONIC DZNEP TREATMENT TRANSIENTLY REDUCED ANIMAL GROWTH. IT HAD NO EFFECT ON MOST ORGANS BUT PROVOKED A REVERSIBLE SPLENOMEGALY, AND PERSISTENT TESTIS REDUCTION AND ERYTHROPOIESIS. DZNEP ADMINISTRATION DID NOT ALTER ANIMAL BEHAVIOR. IN CONCLUSION, THIS STUDY IS ENCOURAGING FOR THE USE OF DZNEP FOR CANCER TREATMENT. INDEED, IT HAS NO EFFECT ON ANIMAL BEHAVIOR, CONFERRING AN ADVANTAGEOUS SAFETY, AND INDUCES IRREVERSIBLE SIDE EFFECTS LIMITED ON TESTIS WHICH ARE UNFORTUNATELY FOUND IN MOST CHEMOTHERAPY TREATMENTS. 2018 19 3652 28 INDIVIDUAL DNA METHYLATION PATTERN SHIFTS IN NANOPARTICLES-EXPOSED WORKERS ANALYZED IN FOUR CONSECUTIVE YEARS. A DNA METHYLATION PATTERN REPRESENTS AN ORIGINAL PLAN OF THE FUNCTION SETTINGS OF INDIVIDUAL CELLS AND TISSUES. THE BASIC STRATEGIES OF ITS DEVELOPMENT AND CHANGES DURING THE HUMAN LIFETIME ARE KNOWN, BUT THE DETAILS RELATED TO ITS MODIFICATION OVER THE YEARS ON AN INDIVIDUAL BASIS HAVE NOT YET BEEN STUDIED. MOREOVER, CURRENT EVIDENCE SHOWS THAT ENVIRONMENTAL EXPOSURE COULD GENERATE CHANGES IN DNA METHYLATION SETTINGS AND, SUBSEQUENTLY, THE FUNCTION OF GENES. IN THIS STUDY, WE ANALYZED THE EFFECT OF CHRONIC EXPOSURE TO NANOPARTICLES (NP) IN OCCUPATIONALLY EXPOSED WORKERS REPEATEDLY SAMPLED IN FOUR CONSECUTIVE YEARS (2016-2019). A DETAILED METHYLATION PATTERN ANALYSIS OF 14 PERSONS (10 EXPOSED AND 4 CONTROLS) WAS PERFORMED ON AN INDIVIDUAL BASIS. A MICROARRAY-BASED APPROACH USING CHIPS, ALLOWING THE ASSESSMENT OF MORE THAN 850 K CPG LOCI, WAS USED. INDIVIDUAL DNA METHYLATION PATTERNS WERE COMPARED BY PRINCIPAL COMPONENT ANALYSIS (PCA). THE RESULTS SHOW THE SHIFT IN DNA METHYLATION PATTERNS IN INDIVIDUAL YEARS IN ALL THE EXPOSED AND CONTROL SUBJECTS. THE OVERALL RANGE OF DIFFERENCES VARIED BETWEEN THE YEARS IN INDIVIDUAL PERSONS. THE DIFFERENCES BETWEEN THE FIRST AND LAST YEAR OF EXAMINATION (A THREE-YEAR TIME PERIOD) SEEM TO BE CONSISTENTLY GREATER IN THE NP-EXPOSED SUBJECTS IN COMPARISON WITH THE CONTROLS. THE SELECTED 14 MOST DIFFERENTLY METHYLATED CG LOCI WERE RELATIVELY STABLE IN THE CHRONICALLY EXPOSED SUBJECTS. IN SUMMARY, THE SPECIFIC TYPE OF LONG-TERM EXPOSURE CAN CONTRIBUTE TO THE FIXING OF RELEVANT EPIGENETIC CHANGES RELATED TO A SPECIFIC ENVIRONMENT AS, E.G., NP INHALATION. 2021 20 476 34 ARSENIC INDUCES FIBROGENIC CHANGES IN HUMAN KIDNEY EPITHELIAL CELLS POTENTIALLY THROUGH EPIGENETIC ALTERATIONS IN DNA METHYLATION. ARSENIC CONTAMINATION IS A SIGNIFICANT PUBLIC HEALTH ISSUE, AND KIDNEY IS ONE OF THE TARGET ORGAN FOR ARSENIC-INDUCED ADVERSE EFFECTS. RENAL FIBROSIS IS A WELL-KNOWN PATHOLOGICAL STAGE FREQUENTLY OBSERVED IN PROGRESSIVE CHRONIC KIDNEY DISEASE (CKD). EPIDEMIOLOGICAL STUDIES IMPLICATE ARSENIC EXPOSURE TO CKD, BUT THE ROLE OF ARSENIC IN KIDNEY FIBROSIS AND THE UNDERLYING MECHANISM IS STILL UNCLEAR. IT IS IN THIS CONTEXT THAT THE CURRENT STUDY EVALUATED THE EFFECTS OF LONG-TERM ARSENIC EXPOSURE ON THE CELLULAR RESPONSE IN MORPHOLOGY, AND MARKER GENES EXPRESSION WITH RESPECT TO FIBROSIS USING HUMAN KIDNEY 2 (HK-2) EPITHELIAL CELLS. RESULTS OF THIS STUDY REVEALED THAT IN ADDITION TO INCREASED GROWTH, HK-2 CELLS UNDERWENT PHENOTYPIC, BIOCHEMICAL AND MOLECULAR CHANGES INDICATIVE OF EPITHELIAL-MESENCHYMAL TRANSITION (EMT) IN RESPONSE TO THE EXPOSURE TO ARSENIC. MOST IMPORTANTLY, THE ARSENIC-EXPOSED CELLS ACQUIRED THE PATHOGENIC FEATURES OF FIBROSIS AS SUPPORTED BY INCREASED EXPRESSION OF MARKERS FOR FIBROSIS, SUCH AS COLLAGEN I, FIBRONECTIN, TRANSFORMING GROWTH FACTOR BETA, AND ALPHA-SMOOTH MUSCLE ACTIN. UPREGULATION OF FIBROSIS ASSOCIATED SIGNALING MOLECULES SUCH AS TISSUE INHIBITOR OF METALLOPROTEINASES-3 AND MATRIX METALLOPROTEINASE-2 AS WELL AS ACTIVATION OF AKT WAS ALSO OBSERVED. ADDITIONALLY, THE EXPRESSION OF EPIGENETIC GENES (DNA METHYLTRANSFERASES 3A AND 3B; METHYL-CPG BINDING DOMAIN 4) WAS INCREASED IN ARSENIC-EXPOSED CELLS. TREATMENT WITH DNA METHYLATION INHIBITOR 5-AZA-2'-DC REVERSED THE EMT PROPERTIES AND RESTORED THE LEVEL OF PHOSPHO-AKT. TOGETHER, THESE DATA FOR THE FIRST TIME SUGGEST THAT LONG-TERM EXPOSURE TO ARSENIC CAN INCREASE THE RISK OF KIDNEY FIBROSIS. ADDITIONALLY, OUR DATA SUGGEST THAT THE ARSENIC-INDUCED FIBROTIC CHANGES ARE, AT LEAST IN PART, MEDIATED BY DNA METHYLATION AND THEREFORE POTENTIALLY CAN BE REVERSED BY EPIGENETIC THERAPEUTICS. 2019