1 745 300 CANNABIS ALTERS EPIGENETIC INTEGRITY AND ENDOCANNABINOID SIGNALLING IN THE HUMAN FOLLICULAR NICHE. STUDY QUESTION: DO PHYTOCANNABINOIDS (PCS) AFFECT FOLLICULAR ENDOCANNABINOID SIGNALLING AND THE EPIGENOME IN THE SURROUNDING GRANULOSA CELLS (GCS)? SUMMARY ANSWER: EXPOSURE TO PCS INCREASES THE EXPRESSION OF ENDOCANNABINOID RECEPTORS AND REDUCES DNA METHYLATION ENZYME EXPRESSION AND GLOBAL DNA METHYLATION IN NAIVE GCS. WHAT IS KNOWN ALREADY: CANNABIS PLANT DERIVATIVES, KNOWN AS PCS, ARE USED FOR MEDICINAL AND RECREATIONAL PURPOSES. THE MAIN PC, TETRAHYDROCANNABINOL (THC), IS THE THIRD MOST COMMONLY USED SUBSTANCE BY WOMEN OF CHILDBEARING AGE, HENCE KNOWLEDGE OF THE EFFECT IT HAS ON REPRODUCTION IS OF UTMOST IMPORTANCE. THC EXERTS ITS EFFECTS VIA RECEPTORS OF THE ENDOCANNABINOID SYSTEM (ECS) AND CAN INTERFERE WITH FOLLICULOGENESIS, OOCYTE DEVELOPMENT AND OVULATION. ENDOCANNABINOIDS HAVE BEEN MEASURED IN FOLLICULAR FLUID (FF) OBTAINED DURING OOCYTE RETRIEVAL AND ARE IMPLICATED IN CONTROLLING FOLLICULOGENESIS. IT HAS BEEN ESTABLISHED THAT IN THE PLACENTA, PCS DISRUPT ENDOCANNABINOID HOMEOSTASIS VIA IMPAIRMENT OF THE SYNTHETIC AND DEGRADING ENZYMES, LEADING TO A NET INCREASE OF ENDOCANNABINOID LEVELS. FINALLY, PREVIOUS STUDIES HAVE SHOWN THAT THC ALTERS METHYLATION AND HISTONE MODIFICATIONS IN SPERM, BRAIN AND BLOOD CELLS. STUDY DESIGN, SIZE, DURATION: THIS STUDY INCLUDED AN IN VIVO COHORT ASSESSMENT OF CANNABIS EXPOSURE AND ITS EFFECTS ON THE FOLLICLE AND IN VITRO ASSAYS CONDUCTED TO VALIDATE THE IN VIVO FINDINGS AND TO EXPLORE POSSIBLE MECHANISMS OF ACTION. PARTICIPANTS/MATERIALS, SETTING, METHODS: A TOTAL OF 318 FF SAMPLES, FROM 261 PATIENTS UNDERGOING IVF TREATMENT AT A PRIVATE FERTILITY CLINIC WHO CONSENTED FOR BIOBANKING BIOLOGICAL WASTE MATERIAL BETWEEN JANUARY 2018 AND JULY 2019, WERE INCLUDED IN THIS STUDY. CONCENTRATIONS OF PCS AND ENDOCANNABINOIDS WERE ASSESSED IN FF BY LIQUID CHROMATOGRAPHY-MASS SPECTROMETRY (LC-MS/MS). EXPOSURE TO PCS WAS DETERMINED BASED ON THESE MEASURED LEVELS. LEVELS OF BOTH ENDOCANNABINOID RECEPTORS (CB1R, CB2R) AND THE DE NOVO DNA METHYLATING ENZYME, DNMT3B, IN GCS WERE ASSESSED BY FLOW CYTOMETRY BOTH IN VITRO AND IN VIVO AND GLOBAL DNA METHYLATION WAS ASSESSED IN VITRO BY ELISA. IN VIVO EFFECTS WERE ASSESSED BY COMPARING SAMPLES POSITIVE FOR AT LEAST ONE PC, WITH SAMPLES NEGATIVE FOR ALL MEASURED PCS. IN VITRO EFFECTS WERE DETERMINED IN NAIVE GCS, OBTAINED CONCURRENTLY WITH FF SAMPLES THAT HAD TESTED NEGATIVE FOR ALL PCS. THESE GCS WERE TREATED WITH DIFFERENT COMBINATIONS OF THE MAIN THREE PCS. MAIN RESULTS AND THE ROLE OF CHANCE: OVERALL, 17 PATIENTS (6.4%) WERE POSITIVE FOR CANNABIS CONSUMPTION. FURTHERMORE, THE PREVALENCE OF CANNABIS POSITIVITY IN THE FF INCREASED FROM 4% OF THE TESTED SAMPLES THAT WERE COLLECTED PRIOR TO NATIONAL LEGALISATION IN OCTOBER 2018 TO 12% OF THOSE COLLECTED FOLLOWING LEGALISATION. OF NOTE, 59% OF PATIENTS WHO TESTED POSITIVE FOR PCS (10 OF 17) REPORTED PREVIOUS OR ONGOING EXPOSURE TO CANNABIS UPON THEIR INITIAL INTAKE. ENDOCANNABINOID LEVELS WERE NOT AFFECTED BY THE PRESENCE OF PCS. CB2R WAS MORE PREVALENT THAN CB1R IN GCS AND ITS EXPRESSION INCREASED FOLLOWING ACUTE AND CHRONIC IN VITRO EXPOSURE TO PCS. THE EXPRESSION OF DNMT3B AND GLOBAL METHYLATION DECREASED FOLLOWING EXPOSURE, SUGGESTING THAT CANNABIS MAY AFFECT THE EPIGENOME IN THE FOLLICULAR NICHE. THE ACUTE CHANGES WERE SUSTAINED THROUGHOUT CHRONIC TREATMENT. LARGE SCALE DATA: N/A. LIMITATIONS, REASONS FOR CAUTION: OUR STUDY IS LIMITED BY LACK OF DETAILS REGARDING MODE, FREQUENCY AND TIMING OF PC CONSUMPTION. MOREOVER, WE WERE NOT ABLE TO ADEQUATELY ASSESS THE EFFECT OF PCS ON IMMEDIATE OR LONG-TERM CLINICAL OUTCOMES, DUE TO THE SMALL SAMPLE SIZE AND THE LACK OF FOLLOW UP. FUTURE, LARGE-SCALE STUDIES SHOULD FOCUS ON ASSESS THE CLINICAL IMPLICATIONS OF CANNABIS EXPOSURE, VALIDATE OUR FINDINGS, AND DETERMINE TO WHAT EXTENT CANNABIS AFFECTS THE EPIGENOME OVARIAN FOLLICLE AND THE DEVELOPING OOCYTE. WIDER IMPLICATIONS OF THE FINDINGS: TO OUR KNOWLEDGE, THIS IS THE FIRST STUDY MEASURING PCS IN FF BY LC-MS/MS. WE SHOW THAT CONSUMING CANNABIS ALTERS THE ECS IN THE DEVELOPING FOLLICLE, AND DIRECTLY AFFECTS DNMT EXPRESSION AND GLOBAL DNA METHYLATION LEVELS. CANNABIS LEGALISATION AND USE IS INCREASING WORLDWIDE, THEREFORE FURTHER UNDERSTANDING ITS ROLE IN FEMALE FERTILITY AND FOLLICULOGENESIS IS CRITICAL. STUDY FUNDING/COMPETING INTEREST(S): ALL FUNDING WAS PROVIDED BY CREATE FERTILITY CENTRE THROUGH THE REINVESTMENT OF CLINICAL EARNINGS. THE AUTHORS DECLARE NO COMPETING INTERESTS. 2021 2 1503 54 DNA METHYLATION AND GENE EXPRESSION DIFFERENCES IN CHILDREN CONCEIVED IN VITRO OR IN VIVO. EPIDEMIOLOGICAL DATA INDICATE THAT CHILDREN CONCEIVED IN VITRO HAVE A GREATER RELATIVE RISK OF LOW BIRTH-WEIGHT, MAJOR AND MINOR BIRTH DEFECTS, AND RARE DISORDERS INVOLVING IMPRINTED GENES, SUGGESTING THAT EPIGENETIC CHANGES MAY BE ASSOCIATED WITH ASSISTED REPRODUCTION. WE EXAMINED DNA METHYLATION AT MORE THAN 700 GENES (1536 CPG SITES) IN PLACENTA AND CORD BLOOD AND MEASURED GENE EXPRESSION LEVELS OF A SUBSET OF GENES THAT DIFFERED IN METHYLATION LEVELS BETWEEN CHILDREN CONCEIVED IN VITRO VERSUS IN VIVO. OUR RESULTS SUGGEST THAT IN VITRO CONCEPTION IS ASSOCIATED WITH LOWER MEAN METHYLATION AT CPG SITES IN PLACENTA AND HIGHER MEAN METHYLATION AT CPG SITES IN CORD BLOOD. WE ALSO FIND THAT IN VITRO CONCEPTION-ASSOCIATED DNA METHYLATION DIFFERENCES ARE ASSOCIATED WITH GENE EXPRESSION DIFFERENCES AT BOTH IMPRINTED AND NON-IMPRINTED GENES. THE RANGE OF INTER-INDIVIDUAL VARIATION IN GENE EXPRESSION OF THE IN VITRO AND IN VIVO GROUPS OVERLAPS SUBSTANTIALLY BUT SOME INDIVIDUALS FROM THE IN VITRO GROUP DIFFER FROM THE IN VIVO GROUP MEAN BY MORE THAN TWO STANDARD DEVIATIONS. SEVERAL OF THE GENES WHOSE EXPRESSION DIFFERS BETWEEN THE TWO GROUPS HAVE BEEN IMPLICATED IN CHRONIC METABOLIC DISORDERS, SUCH AS OBESITY AND TYPE II DIABETES. THESE FINDINGS SUGGEST THAT THERE MAY BE EPIGENETIC DIFFERENCES IN THE GAMETES OR EARLY EMBRYOS DERIVED FROM COUPLES UNDERGOING TREATMENT FOR INFERTILITY. ALTERNATIVELY, ASSISTED REPRODUCTION TECHNOLOGY MAY HAVE AN EFFECT ON GLOBAL PATTERNS OF DNA METHYLATION AND GENE EXPRESSION. IN EITHER CASE, THESE DIFFERENCES OR CHANGES MAY AFFECT LONG-TERM PATTERNS OF GENE EXPRESSION. 2009 3 1784 64 EFFECT OF ALCOHOL CONSUMPTION ON CPG METHYLATION IN THE DIFFERENTIALLY METHYLATED REGIONS OF H19 AND IG-DMR IN MALE GAMETES: IMPLICATIONS FOR FETAL ALCOHOL SPECTRUM DISORDERS. BACKGROUND: EXPOSURE TO ALCOHOL IN UTERO IS THE MAIN ATTRIBUTABLE CAUSE OF FETAL ALCOHOL SPECTRUM DISORDERS (FASD) WHICH IN ITS MOST SEVERE FORM IS CHARACTERIZED BY IRREVERSIBLE BEHAVIORAL AND COGNITIVE DISABILITY. PATERNAL PRECONCEPTION DRINKING IS NOT CONSIDERED TO BE A SIGNIFICANT RISK FACTOR, EVEN THOUGH ANIMAL STUDIES HAVE DEMONSTRATED THAT CHRONIC PATERNAL ALCOHOL CONSUMPTION HAS A DETRIMENTAL EFFECT ON THE PHYSICAL AND MENTAL DEVELOPMENT OF OFFSPRING EVEN IN THE ABSENCE OF IN UTERO ALCOHOL EXPOSURE. IT HAS BEEN DOCUMENTED THAT ALCOHOL CAN REDUCE THE LEVELS AND ACTIVITY OF DNA METHYLTRANSFERASES RESULTING IN DNA HYPOMETHYLATION AND THAT REDUCED METHYLTRANSFERASE ACTIVITY CAN CAUSE ACTIVATION OF NORMALLY SILENCED GENES. THE AIM OF THIS STUDY WAS TO ESTABLISH A LINK BETWEEN ALCOHOL USE IN MEN AND HYPOMETHYLATION OF PATERNALLY IMPRINTED LOCI IN SPERM DNA IN GENOMIC REGIONS CRITICAL FOR EMBRYONIC DEVELOPMENT, THUS PROVIDING A MECHANISM FOR PATERNAL EFFECTS IN THE AETIOLOGY OF FASD. METHODS: SPERM DNA FROM MALE VOLUNTEERS WAS BISULFITE TREATED AND THE METHYLATION PATTERNS OF 2 DIFFERENTIALLY METHYLATED REGIONS (DMRS), H19 AND IG-DMR, ANALYZED FOLLOWING SEQUENCING OF INDIVIDUAL CLONES. THE METHYLATION PATTERNS WERE CORRELATED WITH THE ALCOHOL CONSUMPTION LEVELS OF THE VOLUNTEER MALES. RESULTS: THERE WAS A PATTERN OF INCREASED DEMETHYLATION WITH ALCOHOL CONSUMPTION AT THE 2 IMPRINTED LOCI WITH A SIGNIFICANT DIFFERENCE OBSERVED AT THE IG-DMR BETWEEN THE NONDRINKING AND HEAVY ALCOHOL CONSUMING GROUPS. GREATER INTER-INDIVIDUAL VARIATION IN AVERAGE METHYLATION WAS OBSERVED AT THE H19 DMR AND INDIVIDUAL CLONES WERE MORE EXTENSIVELY DEMETHYLATED THAN THOSE OF THE IG-DMR. CPG SITE #4 IN THE IG-DMR WAS PREFERENTIALLY DEMETHYLATED AMONG ALL INDIVIDUALS AND ALONG WITH THE H19 DMR CPG SITE #7 LOCATED WITHIN THE CTCF BINDING SITE 6 SHOWED SIGNIFICANT DEMETHYLATION IN THE ALCOHOL CONSUMING GROUPS COMPARED WITH THE CONTROL GROUP. CONCLUSION: THIS STUDY DEMONSTRATES A CORRELATION BETWEEN CHRONIC ALCOHOL USE AND DEMETHYLATION OF NORMALLY HYPERMETHYLATED IMPRINTED REGIONS IN SPERM DNA. WE HYPOTHESIZE THAT, SHOULD THESE EPIGENETIC CHANGES IN IMPRINTED GENES BE TRANSMITTED THROUGH FERTILIZATION, THEY WOULD ALTER THE CRITICAL GENE EXPRESSION DOSAGES REQUIRED FOR NORMAL PRENATAL DEVELOPMENT RESULTING IN OFFSPRING WITH FEATURES OF FASD. 2009 4 904 62 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 5 1967 55 EPIGENETIC ALTERATION OF THE DOPAMINE TRANSPORTER GENE IN ALCOHOL-DEPENDENT PATIENTS IS ASSOCIATED WITH AGE. CHRONIC ALCOHOL ABUSE AND DEPENDENCE ARE ASSOCIATED WITH DYSFUNCTIONAL DOPAMINERGIC NEUROTRANSMISSION IN MESOCORTICOLIMBIC CIRCUITS. GENETIC AND ENVIRONMENTAL FACTORS HAVE BEEN SHOWN TO MODULATE SUSCEPTIBILITY TO ALCOHOL DEPENDENCE, AND BOTH MAY ACT THROUGH EPIGENETIC MECHANISMS THAT CAN MODULATE GENE EXPRESSION, E.G. DNA METHYLATION AT CPG SITES. RECENT STUDIES HAVE SUGGESTED THAT DNA METHYLATION PATTERNS MAY CHANGE OVER TIME. HOWEVER, FEW DATA ARE AVAILABLE CONCERNING THE RATE OF THESE CHANGES IN SPECIFIC GENES. A RECENT STUDY FOUND THAT HYPERMETHYLATION OF THE PROMOTER OF THE DOPAMINE TRANSPORTER (DAT) GENE WAS POSITIVELY CORRELATED WITH ALCOHOL DEPENDENCE AND NEGATIVELY CORRELATED WITH ALCOHOL CRAVING. THE AIM OF THE PRESENT STUDY WAS TO REPLICATE THESE FINDINGS IN A LARGER SAMPLE OF ALCOHOL-DEPENDENT PATIENTS AND POPULATION-BASED CONTROLS MATCHED FOR AGE AND SEX. NO DIFFERENCE IN METHYLATION LEVEL WAS OBSERVED BETWEEN PATIENTS AND CONTROLS, AND NO DIFFERENCE IN METHYLATION LEVEL WAS OBSERVED BEFORE AND AFTER ALCOHOL WITHDRAWAL IN PATIENTS. HOWEVER, PATIENTS WITH MORE SEVERE CRAVING SHOWED A TREND TOWARDS LOWER DAT METHYLATION LEVELS (P = 0.07), WHICH IS CONSISTENT WITH PREVIOUS FINDINGS. FURTHERMORE, IN OUR OVERALL SAMPLE, DAT METHYLATION LEVELS INCREASED WITH AGE. INTERESTINGLY, A SEPARATE ANALYSIS OF PATIENTS SUGGESTED THAT THIS FINDING WAS MAINLY DRIVEN BY THE PATIENT GROUP. ALTHOUGH THE PRESENT DATA DO NOT CLARIFY WHETHER CHRONIC ALCOHOL ABUSE IS RESPONSIBLE FOR THIS PHENOMENON OR MERELY ENHANCES AN AGEING-SPECIFIC PROCESS, OUR FINDINGS SUGGEST THAT HYPERMETHYLATION IN ALCOHOL-DEPENDENT PATIENTS IS A CONSEQUENCE, RATHER THAN A CAUSE, OF THE DISORDER. 2014 6 3136 55 GLOBAL DNA METHYLATION LEVELS IN WHITE BLOOD CELLS OF PATIENTS WITH CHRONIC HEROIN USE DISORDER. A PROSPECTIVE STUDY. BACKGROUND: INCREASING SCIENTIFIC EVIDENCE SHOWS THE SIGNIFICANT ROLE OF EPIGENETIC MECHANISMS IN DRUG USE DISORDER, ABSTINENCE AND RELAPSE. STUDIES ON HUMAN SUBJECTS ARE LIMITED COMPARED TO THOSE ON ANIMALS, FOR VARIOUS REASONS SUCH AS POLY-SUBSTANCE ABUSE, HIGH DROP-OUT RATE AND TECHNICAL DIFFICULTIES. OBJECTIVES: OUR GOAL WAS TO EVALUATE WHETHER A MONITORED ABSTINENCE PERIOD OF 21 DAYS COULD INDUCE CHANGES IN GLOBAL DNA METHYLATION IN CHRONIC HEROIN USERS. METHOD: IN THE CURRENT STUDY, WE PRESENT DATA ON GLOBAL DNA METHYLATION ON A SET OF 18 MALE PATIENTS WITH CHRONIC HEROIN USE DISORDER, CAREFULLY SELECTED BASED ON INCLUSION AND EXCLUSION CRITERIA, WHO WERE HOSPITALIZED AND CLOSELY MONITORED DURING A 21-DAY DETOXIFICATION PROGRAM, ONE OF THE FEW WHERE NO OPIOID AGONIST IS ADMINISTERED. THE PARTICIPANTS WERE SAMPLED TWICE, ONCE UPON ENROLMENT TO THE PROGRAM AND ONCE UPON COMPLETION. RESULTS: ACCORDING TO OUR RESULTS, NO DIFFERENCE IN GLOBAL DNA METHYLATION WAS DETECTED BETWEEN SAMPLES COLLECTED UPON ENROLMENT AND SAMPLES COLLECTED UPON COMPLETION OF THE PROGRAM. CONCLUSION: THE FINDINGS OF THIS STUDY DO NOT RULE OUT THE POSSIBILITY THAT THE 21-DAY ABSTINENCE PERIOD WAS NOT LONG ENOUGH TO OBSERVE CHANGES IN GLOBAL DNA METHYLATION, OR THAT ABSTINENCE INDUCED SITE-SPECIFIC METHYLATION CHANGES (BUT NOT GLOBAL CHANGES), THAT CERTAINLY MERIT FURTHER EVALUATION. 2021 7 1599 51 DNA METHYLATION SIGNATURE OF CHILDHOOD CHRONIC PHYSICAL AGGRESSION IN T CELLS OF BOTH MEN AND WOMEN. BACKGROUND: HIGH FREQUENCY OF PHYSICAL AGGRESSION IS THE CENTRAL FEATURE OF SEVERE CONDUCT DISORDER AND IS ASSOCIATED WITH A WIDE RANGE OF SOCIAL, MENTAL AND PHYSICAL HEALTH PROBLEMS. WE HAVE PREVIOUSLY TESTED THE HYPOTHESIS THAT DIFFERENTIAL DNA METHYLATION SIGNATURES IN PERIPHERAL T CELLS ARE ASSOCIATED WITH A CHRONIC AGGRESSION TRAJECTORY IN MALES. DESPITE THE FACT THAT SEX DIFFERENCES APPEAR TO PLAY A PIVOTAL ROLE IN DETERMINING THE DEVELOPMENT, MAGNITUDE AND FREQUENCY OF AGGRESSION, MOST OF PREVIOUS STUDIES FOCUSED ON MALES, SO LITTLE IS KNOWN ABOUT FEMALE CHRONIC PHYSICAL AGGRESSION. WE THEREFORE TESTED HERE WHETHER OR NOT THERE IS A SIGNATURE OF PHYSICAL AGGRESSION IN FEMALE DNA METHYLATION AND, IF THERE IS, HOW IT RELATES TO THE SIGNATURE OBSERVED IN MALES. METHODOLOGY/PRINCIPAL FINDINGS: METHYLATION PROFILES WERE CREATED USING THE METHOD OF METHYLATED DNA IMMUNOPRECIPITATION (MEDIP) FOLLOWED BY MICROARRAY HYBRIDIZATION AND STATISTICAL AND BIOINFORMATIC ANALYSES ON T CELL DNA OBTAINED FROM ADULT WOMEN WHO WERE FOUND TO BE ON A CHRONIC PHYSICAL AGGRESSION TRAJECTORY (CPA) BETWEEN 6 AND 12 YEARS OF AGE COMPARED TO WOMEN WHO FOLLOWED A NORMAL PHYSICAL AGGRESSION TRAJECTORY. WE CONFIRMED THE EXISTENCE OF A WELL-DEFINED, GENOME-WIDE SIGNATURE OF DNA METHYLATION ASSOCIATED WITH CHRONIC PHYSICAL AGGRESSION IN THE PERIPHERAL T CELLS OF ADULT FEMALES THAT INCLUDES MANY OF THE GENES SIMILARLY ASSOCIATED WITH PHYSICAL AGGRESSION IN THE SAME CELL TYPES OF ADULT MALES. CONCLUSIONS: THIS STUDY IN A SMALL NUMBER OF WOMEN PRESENTS PRELIMINARY EVIDENCE FOR A GENOME-WIDE VARIATION IN PROMOTER DNA METHYLATION THAT ASSOCIATES WITH CPA IN WOMEN THAT WARRANT LARGER STUDIES FOR FURTHER VERIFICATION. A SIGNIFICANT PROPORTION OF THESE ASSOCIATIONS WERE PREVIOUSLY OBSERVED IN MEN WITH CPA SUPPORTING THE HYPOTHESIS THAT THE EPIGENETIC SIGNATURE OF EARLY LIFE AGGRESSION IN FEMALES IS COMPOSED OF A COMPONENT SPECIFIC TO FEMALES AND ANOTHER COMMON TO BOTH MALES AND FEMALES. 2014 8 990 46 CHRONIC SOCIAL STRESS INDUCES DNA METHYLATION CHANGES AT AN EVOLUTIONARY CONSERVED INTERGENIC REGION IN CHROMOSOME X. CHRONIC STRESS RESULTING FROM PROLONGED EXPOSURE TO NEGATIVE LIFE EVENTS INCREASES THE RISK OF MOOD AND ANXIETY DISORDERS. ALTHOUGH CHRONIC STRESS CAN CHANGE GENE EXPRESSION RELEVANT FOR BEHAVIOR, MOLECULAR REGULATORS OF THIS CHANGE HAVE NOT BEEN FULLY DETERMINED. ONE PROCESS THAT COULD PLAY A ROLE IS DNA METHYLATION, AN EPIGENETIC PROCESS WHEREBY A METHYL GROUP IS ADDED ONTO NUCLEOTIDES, PREDOMINANTLY CYTOSINE IN THE CPG CONTEXT, AND WHICH CAN BE INDUCED BY CHRONIC STRESS. IT IS UNKNOWN TO WHAT EXTENT CHRONIC SOCIAL DEFEAT, A MODEL OF HUMAN SOCIAL STRESS, INFLUENCES DNA METHYLATION PATTERNS ACROSS THE GENOME. OUR STUDY ADDRESSED THIS QUESTION BY USING A TARGETED-CAPTURE APPROACH CALLED METHYL-SEQ TO INVESTIGATE DNA METHYLATION PATTERNS OF THE DENTATE GYRUS AT PUTATIVE REGULATORY REGIONS ACROSS THE MOUSE GENOME FROM MICE EXPOSED TO 14 DAYS OF SOCIAL DEFEAT. FINDINGS WERE REPLICATED IN INDEPENDENT COHORTS BY BISULFITE-PYROSEQUENCING. TWO DIFFERENTIALLY METHYLATED REGIONS (DMRS) WERE IDENTIFIED. ONE DMR WAS LOCATED AT INTRON 9 OF DROSHA, AND IT SHOWED REDUCED METHYLATION IN STRESSED MICE. THIS OBSERVATION REPLICATED IN ONE OF TWO INDEPENDENT COHORTS. A SECOND DMR WAS IDENTIFIED AT AN INTERGENIC REGION OF CHROMOSOME X, AND METHYLATION IN THIS REGION WAS INCREASED IN STRESSED MICE. THIS METHYLATION DIFFERENCE REPLICATED IN TWO INDEPENDENT COHORTS AND IN MAJOR DEPRESSIVE DISORDER (MDD) POSTMORTEM BRAINS. THESE RESULTS HIGHLIGHT A REGION NOT PREVIOUSLY KNOWN TO BE DIFFERENTIALLY METHYLATED BY CHRONIC SOCIAL DEFEAT STRESS AND WHICH MAY BE INVOLVED IN MDD. 2018 9 3652 55 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 10 6311 47 THE RELATION BETWEEN DNA METHYLATION PATTERNS AND SERUM CYTOKINE LEVELS IN COMMUNITY-DWELLING ADULTS: A PRELIMINARY STUDY. BACKGROUND: THE LEVELS OF CIRCULATING CYTOKINES FLUCTUATE WITH AGE, ACUTE ILLNESS, AND CHRONIC DISEASE, AND ARE PREDICTIVE OF MORTALITY; THIS IS ALSO TRUE FOR PATTERNS OF DNA (CPG) METHYLATION. GIVEN THAT IMMUNE CELLS ARE PARTICULARLY SENSITIVE TO CHANGES IN THE CONCENTRATION OF CYTOKINES IN THEIR MICROENVIRONMENT, WE HYPOTHESIZED THAT SERUM LEVELS OF TNF, IL-6, IL-8 AND IL-10 WOULD CORRELATE WITH GENOME-WIDE ALTERATIONS IN THE DNA METHYLATION LEVELS OF BLOOD LEUKOCYTES. TO TEST THIS, WE EVALUATED COMMUNITY-DWELLING ADULTS (N = 14; 48-78 YEARS OLD) RECRUITED TO A PILOT STUDY FOR THE CANADIAN LONGITUDINAL STUDY ON AGING (CLSA), EXAMINING DNA METHYLATION PATTERNS IN PERIPHERAL BLOOD MONONUCLEAR CELLS USING THE ILLUMINA HUMANMETHYLATION 450 K BEADCHIP. RESULTS: WE SHOW THAT, APART FROM AGE, SERUM IL-10 LEVELS EXHIBITED THE MOST SUBSTANTIAL ASSOCIATION TO DNA METHYLATION PATTERNS, FOLLOWED BY TNF, IL-6 AND IL-8. FURTHERMORE, WHILE THE LEVELS OF THESE CYTOKINES WERE HIGHER IN ELDERLY ADULTS, NO ASSOCIATIONS WITH EPIGENETIC ACCELERATED AGING, DERIVED USING THE EPIGENETIC CLOCK, WERE OBSERVED. CONCLUSIONS: AS A PRELIMINARY STUDY WITH A SMALL SAMPLE SIZE, THE CONCLUSIONS DRAWN FROM THIS WORK MUST BE VIEWED WITH CAUTION; HOWEVER, OUR OBSERVATIONS ARE ENCOURAGING AND CERTAINLY WARRANT MORE SUITABLY POWERED STUDIES OF THIS RELATIONSHIP. 2017 11 344 57 ALTERED BDNF METHYLATION IN PATIENTS WITH CHRONIC MUSCULOSKELETAL PAIN AND HIGH BIOPSYCHOSOCIAL COMPLEXITY. PURPOSE: THE INTERMED INSTRUMENT, WHICH WAS DEVELOPED TO MEASURE PATIENT'S BIOPSYCHOSOCIAL (BPS) COMPLEXITY, REPRESENTS A POWERFUL DIAGNOSTIC AND THERAPEUTIC TOOL. EPIGENETIC CHANGES ARE THE INTERFACE BETWEEN SIGNALS FROM THE ENVIRONMENT AND GENETIC MODIFICATIONS, AFFECTING GENE EXPRESSION, IN PARTICULAR, BY DNA METHYLATION OF CPG DINUCLEOTIDES IN PROMOTOR REGIONS OF THE CORRESPONDING GENES. THE BRAIN-DERIVED NEUROTROPHIC FACTOR (BDNF) GENE PLAYS A CRUCIAL ROLE IN THE CENTRAL SENSITIZATION (CS) OF PAIN. IN THIS STUDY, WE HYPOTHESIZED THAT CHRONIC PAIN MODIFIES THE METHYLATION LEVELS OF THE BDNF GENE IN A MANNER THAT IS INTERCONNECTED WITH THE BPS STATUS. PATIENTS AND METHODS: FIFTY-EIGHT CHRONIC MUSCULOSKELETAL PAIN PATIENTS (CMSP) WERE ENROLLED IN THE STUDY. DNA WAS EXTRACTED FROM BLOOD SAMPLES, THE METHYLATION LEVELS OF 13 CPG SITES IN THE BDNF PROMOTER WERE MEASURED BY PYROSEQUENCING, AND ASSOCIATION STUDIES WITH VARIOUS PATIENT PARAMETERS AND THE INTERMED SCORES WERE PERFORMED. RESULTS: INTERESTINGLY, A NEGATIVE CORRELATION (-0.40) WAS FOUND BETWEEN THE TOTAL INTERMED SCORES AND THE AVERAGE CPG METHYLATION VALUES OF THE BDNF GENE, BUT NO CORRELATION WAS OBSERVED WITH THE SEVERITY OF PAIN, DEGREE OF ANXIETY, DEPRESSION, OR KINESIOPHOBIA AND CATASTROPHISM. MOREOVER, THE ASSOCIATION WAS INDEPENDENT OF AGE, SEX AND LEVEL OF COMORBIDITIES. CONCLUSION: THIS RESULT SHOWS THAT CMSP, IN ASSOCIATION WITH ITS BIOPSYCHOSOCIAL CONTEXT, EPIGENETICALLY DECREASES THE DEGREE OF METHYLATION OF THE BDNF PROMOTER AND SHOULD THEREFORE INCREASE THE LEVEL OF BDNF TRANSCRIPTION. IT ALSO SUGGESTS A ROLE OF THE INTERMED TOOL TO DETECT A RELATIONSHIP BETWEEN THE BPS COMPLEXITY AND THE EPIGENETIC CONTROL OF A TARGET GENE. THE POSSIBLE UPREGULATION OF BDNF EXPRESSION MIGHT BE, AT LEAST IN PART, THE SIGNAL FOR CHRONIC PAIN-INDUCED CENTRAL SENSITIZATION (CS). THIS COULD PARTLY EXPLAIN WHY PATIENTS WITH A HIGHER LEVEL OF COMPLEXITY FEEL MORE PAIN THAN THOSE WITH LOWER COMPLEXITY. 2020 12 5682 43 SHORT-TERM CHANGES IN GLOBAL METHYLATION AND HYDROXYMETHYLATION DURING ALCOHOL DETOXIFICATION. ALCOHOL DEPENDENCE IS A COMMON PUBLIC HEALTH PROBLEM AND EPIGENETICS MAY OFFER NEW ASPECTS IN UNDERSTANDING THE BIOLOGICAL AND GENETIC UNDERPINNINGS AND IMPROVE TREATMENT OF THIS COMPLEX DISEASE. SUPPOSEDLY, METHYLATION AND HYDROXYMETHYLATION ARE ALTERED IN BRAIN TISSUES AND IN SYNAPSE-RELATED GENES DUE TO CHRONIC ALCOHOL INTAKE AND DURING WITHDRAWAL. TO ASSESS POTENTIAL EPIGENETIC CHANGES AFTER CESSATION OF CHRONIC ALCOHOL INTAKE, WE COMPARED 23 ALCOHOL-DEPENDENT INDIVIDUALS DURING INPATIENT ALCOHOL DETOXIFICATION WITH 13 CAREFULLY MATCHED CONTROLS. BLOOD SAMPLES WERE TAKEN ON THE DAY OF ADMISSION, AFTER ONE AND AFTER TWO WEEKS AT THE END OF INPATIENT TREATMENT. GENOME-WIDE GLOBAL METHYLATION AND GLOBAL DNA HYDROXYMETHYLATION WERE COMPARED ACROSS GROUPS. THERE WERE SIGNIFICANT DIFFERENCES IN GLOBAL METHYLATION ACROSS TIME FROM ADMISSION TO ONE AND TWO WEEKS OF INPATIENT WITHDRAWAL (P < 0.001). THESE FINDINGS WERE PARALLELED TO CHANGES IN GLOBAL DNA HYDROXYMETHYLATION ACROSS TIME WHEN AGE WAS EMPLOYED AS A COFACTOR (P < 0.001). SEVERAL POTENTIALLY INFLUENCING VARIABLES LIKE SEVERITY OF WITHDRAWAL, DOSE OF WITHDRAWAL MEDICATION AND ALCOHOL INTAKE BEFORE ADMISSION DID NOT YIELD SIGNIFICANT INFLUENCE ON EPIGENETIC CHANGES. THE RESULTS CONFIRM PREVIOUS FINDINGS OF SIGNIFICANT ALTERATIONS OF EPIGENETIC PATTERNS DURING ALCOHOL INTOXICATION AND PRESENT FOR THE FIRST TIME HYDROXYMETHYLATION CHANGES IN THESE INDIVIDUALS. 2019 13 70 48 A METHOD TO DETECT DIFFERENTIALLY METHYLATED LOCI WITH NEXT-GENERATION SEQUENCING. EPIGENETIC CHANGES, ESPECIALLY DNA METHYLATION AT CPG LOCI HAVE IMPORTANT IMPLICATIONS IN CANCER AND OTHER COMPLEX DISEASES. WITH THE DEVELOPMENT OF NEXT-GENERATION SEQUENCING (NGS), IT IS FEASIBLE TO GENERATE DATA TO INTERROGATE THE DIFFERENCE IN METHYLATION STATUS FOR GENOME-WIDE LOCI USING CASE-CONTROL DESIGN. HOWEVER, A PROPER AND EFFICIENT STATISTICAL TEST IS LACKING. THERE ARE SEVERAL CHALLENGES. FIRST, UNLIKE METHYLATION EXPERIMENTS USING MICROARRAYS, WHERE THERE IS ONE MEASURE OF METHYLATION FOR ONE INDIVIDUAL AT A PARTICULAR CPG SITE, HERE WE HAVE THE COUNTS OF METHYLATION ALLELE AND UNMETHYLATION ALLELE FOR EACH INDIVIDUAL. SECOND, DUE TO THE NATURE OF SAMPLE PREPARATION, THE MEASURED METHYLATION REFLECTS THE METHYLATION STATUS OF A MIXTURE OF CELLS INVOLVED IN SAMPLE PREPARATION. THEREFORE, THE UNDERLYING DISTRIBUTION OF THE MEASURED METHYLATION LEVEL IS UNKNOWN, AND A ROBUST TEST IS MORE DESIRABLE THAN PARAMETRIC APPROACH. THIRD, CURRENTLY NGS MEASURES METHYLATION AT OVER 2 MILLION CPG SITES. ANY STATISTICAL TESTS HAVE TO BE COMPUTATIONALLY EFFICIENT IN ORDER TO BE APPLIED TO THE NGS DATA. TAKING THESE CHALLENGES INTO ACCOUNT, WE PROPOSE A TEST FOR DIFFERENTIAL METHYLATION BASED ON CLUSTERED DATA ANALYSIS BY MODELING THE METHYLATION COUNTS. WE PERFORMED SIMULATIONS TO SHOW THAT IT IS ROBUST UNDER SEVERAL DISTRIBUTIONS FOR THE MEASURED METHYLATION LEVELS. IT HAS GOOD POWER AND IS COMPUTATIONALLY EFFICIENT. FINALLY, WE APPLY THE TEST TO OUR NGS DATA ON CHRONIC LYMPHOCYTIC LEUKEMIA. THE RESULTS INDICATE THAT IT IS A PROMISING AND PRACTICAL TEST. 2013 14 457 44 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 15 948 32 CHRONIC METABOLIC DERANGEMENT-INDUCED COGNITIVE DEFICITS AND NEUROTOXICITY ARE ASSOCIATED WITH REST INACTIVATION. CHRONIC METABOLIC ALTERATIONS MAY REPRESENT A RISK FACTOR FOR THE DEVELOPMENT OF COGNITIVE IMPAIRMENT, DEMENTIA, OR NEURODEGENERATIVE DISEASES. HYPERGLYCEMIA AND OBESITY ARE KNOWN TO IMPRINT EPIGENETIC MARKERS THAT COMPROMISE THE PROPER EXPRESSION OF CELL SURVIVAL GENES. HERE, WE SHOWED THAT CHRONIC HYPERGLYCEMIA (60 DAYS) INDUCED BY A SINGLE INTRAPERITONEAL INJECTION OF STREPTOZOTOCIN COMPROMISED COGNITION BY REDUCING HIPPOCAMPAL ERK SIGNALING AND BY INDUCING NEUROTOXICITY IN RATS. THE MECHANISMS APPEAR TO BE LINKED TO REDUCED ACTIVE DNA DEMETHYLATION AND DIMINISHED EXPRESSION OF THE NEUROPROTECTIVE TRANSCRIPTION FACTOR REST. THE IMPACT OF THE RELATIONSHIP BETWEEN ADIPOSITY AND DNA HYPERMETHYLATION ON REST EXPRESSION WAS ALSO DEMONSTRATED IN PERIPHERAL BLOOD MONONUCLEAR CELLS IN OBESE CHILDREN WITH REDUCED LEVELS OF BLOOD ASCORBATE. THE REVERSIBLE NATURE OF EPIGENETIC MODIFICATIONS AND THE COGNITIVE IMPAIRMENT REPORTED IN OBESE CHILDREN, ADOLESCENTS, AND ADULTS SUGGEST THAT THE CORRECTION OF THE ANTHROPOMETRY AND THE PERIPHERAL METABOLIC ALTERATIONS WOULD PROTECT BRAIN HOMEOSTASIS AND REDUCE THE RISK OF DEVELOPING NEURODEGENERATIVE DISEASES. 2019 16 2489 44 EPIGENETICALLY MODIFIED NUCLEOTIDES IN CHRONIC HEROIN AND COCAINE TREATED MICE. EPIGENETIC CHANGES INCLUDE THE ADDITION OF A METHYL GROUP TO THE 5' CARBON OF THE CYTOSINE RING, KNOWN AS DNA METHYLATION, WHICH RESULTS IN THE GENERATION OF THE FIFTH DNA BASE, NAMELY 5-METHYLCYTOSINE. DURING ACTIVE OR PASSIVE DEMETHYLATION, AN INTERMEDIATE MODIFIED BASE IS FORMED, 5-HYDROXYMETHYLCYTOSINE. WE HAVE CURRENTLY QUANTIFIED 5-METHYLCYTOSINE AND 5-HYDROXYMETHYLCYTOSINE IN THE LIVER AND BRAIN OF MICE TREATED WITH COCAINE OR HEROIN, USING LIQUID CHROMATOGRAPHY/TANDEM MASS SPECTROMETRY (LC-MS/MS). OUR RESULTS SHOW THAT GLOBAL 5-METHYLCYTOSINE LEVELS ARE NOT AFFECTED BY HEROIN OR COCAINE ADMINISTRATION, NEITHER IN THE LIVER NOR IN THE BRAIN. HOWEVER, 5-HYDROXYMETHYLCYTOSINE LEVELS ARE REDUCED IN THE LIVER FOLLOWING COCAINE ADMINISTRATION, WHILE THEY ARE NOT AFFECTED BY COCAINE IN THE BRAIN OR BY HEROIN ADMINISTRATION IN THE LIVER AND THE BRAIN. ELUCIDATION OF THE EPIGENETIC PHENOMENA THAT TAKES PLACE WITH RESPECT TO DRUG ABUSE AND ADDICTION, VIA QUANTITATIVE ANALYSIS OF DIFFERENT MODIFIED BASES, MAY ENABLE A BETTER UNDERSTANDING OF THE UNDERLYING MECHANISMS AND MAY LEAD TO MORE PERSONALIZED AND EFFECTIVE TREATMENT OPTIONS. 2014 17 4009 48 LOW LEVELS OF CD INDUCE PERSISTING EPIGENETIC MODIFICATIONS AND ACCLIMATION MECHANISMS IN THE EARTHWORM LUMBRICUS TERRESTRIS. TOXIC EFFECTS OF CADMIUM (CD), A COMMON SOIL POLLUTANT, ARE STILL NOT VERY WELL UNDERSTOOD, PARTICULARLY IN REGARD TO ITS EPIGENETIC IMPACT. THEREFORE, THE AIM OF THIS STUDY WAS TO ASSESS DNA METHYLATION CHANGES AND THEIR PERSISTENCE IN THE EARTHWORM LUMBRICUS TERRESTRIS UPON CHRONIC LOW DOSE CD EXPOSURE USING METHYLATION SENSITIVE AMPLIFICATION POLYMORPHISM (MSAP). MOREOVER, THE BIOMARKER RESPONSE AND FITNESS OF THE EARTHWORMS, AS WELL AS THE EXPRESSION OF DETOXIFICATION-RELATED GENES (METALLOTHIONEIN (MT) AND PHYTOCHELATIN SYNTHASE (PCS)) WAS EVALUATED. LOW LEVELS OF CD CAUSED AN INCREASE IN GENOME-WIDE DNA METHYLATION, WHICH REMAINED PARTLY MODIFIED, EVEN AFTER SEVERAL MONTHS OF RECOVERY IN UNPOLLUTED SOIL. INCREASED CELLULAR STRESS SEEMED TO DECREASE AFTER TWO WEEKS OF EXPOSURE WHEREAS FITNESS PARAMETERS REMAINED UNAFFECTED BY CD, PROBABLY AS A RESULT FROM THE ACTIVATION OF DETOXIFICATION MECHANISMS LIKE THE EXPRESSION OF MTS. INTERESTINGLY, EVEN THOUGH THE LEVEL OF CD EXPOSURE WAS VERY LOW, MT EXPRESSION LEVELS INDICATE THE DEVELOPMENT OF ACCLIMATION MECHANISMS. TAKEN TOGETHER, THIS STUDY DEMONSTRATES THAT ACCLIMATION, AS WELL AS EPIGENETIC MODIFICATIONS CAN OCCUR ALREADY IN MODERATELY POLLUTED ENVIRONMENTS. IN ADDITION, THESE EFFECTS CAN HAVE LONG-LASTING IMPACTS ON KEY SPECIES OF SOIL INVERTEBRATES AND MIGHT PERSIST LONG AFTER THE ACTUAL HEAVY METAL CHALLENGE HAS PASSED. 2017 18 287 39 AGING AND CHRONIC SUN EXPOSURE CAUSE DISTINCT EPIGENETIC CHANGES IN HUMAN SKIN. EPIGENETIC CHANGES ARE WIDELY CONSIDERED TO PLAY AN IMPORTANT ROLE IN AGING, BUT EXPERIMENTAL EVIDENCE TO SUPPORT THIS HYPOTHESIS HAS BEEN SCARCE. WE HAVE USED ARRAY-BASED ANALYSIS TO DETERMINE GENOME-SCALE DNA METHYLATION PATTERNS FROM HUMAN SKIN SAMPLES AND TO INVESTIGATE THE EFFECTS OF AGING, CHRONIC SUN EXPOSURE, AND TISSUE VARIATION. OUR RESULTS REVEAL A HIGH DEGREE OF TISSUE SPECIFICITY IN THE METHYLATION PATTERNS AND ALSO SHOWED VERY LITTLE INTERINDIVIDUAL VARIATION WITHIN TISSUES. DATA STRATIFICATION BY AGE REVEALED THAT DNA FROM OLDER INDIVIDUALS WAS CHARACTERIZED BY A SPECIFIC HYPERMETHYLATION PATTERN AFFECTING LESS THAN 1% OF THE MARKERS ANALYZED. INTERESTINGLY, STRATIFICATION BY SUN EXPOSURE PRODUCED A FUNDAMENTALLY DIFFERENT PATTERN WITH A SIGNIFICANT TREND TOWARDS HYPOMETHYLATION. OUR RESULTS THUS IDENTIFY DEFINED AGE-RELATED DNA METHYLATION CHANGES AND SUGGEST THAT THESE ALTERATIONS MIGHT CONTRIBUTE TO THE PHENOTYPIC CHANGES ASSOCIATED WITH SKIN AGING. 2010 19 1511 54 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 20 3981 52 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