1   495 207 ASSESSMENT OF THE HEALTH EFFECTS OF TRICHLOROETHYLENE. THE EPIDEMIOLOGICAL STUDIES PERFORMED THUS FAR HAVE PRESENTED ONLY LIMITED EVIDENCE FOR THE CARCINOGENICITY OF TRICHLOROETHYLENE (TRI) TO HUMANS. HOWEVER, THESE STUDIES HAD DRAWBACKS SUCH AS INSUFFICIENT SIZE OF COHORT, SHORT OBSERVATION PERIOD, AND INADEQUATE TRI EXPOSURE ASSESSMENT; THEREFORE, NO CONCRETE CONCLUSION HAS BEEN REACHED CONCERNING TRI CARCINOGENICITY TO HUMANS. DESPITE THE LIMITED EPIDEMIOLOGICAL EVIDENCE AS TO THE CARCINOGENICITY OF TRI, THE INTERNATIONAL AGENCY FOR RESEARCH ON CANCER (IARC) HAS CHANGED THE CARCINOGENICITY CLASSIFICATION OF TRI FROM GROUP 3 (NOT CLASSIFIABLE AS TO CARCINOGENICITY TO HUMANS) TO GROUP 2A (PROBABLY CARCINOGENIC TO HUMANS). IN REGARD TO THE NEW CLASSIFICATION BY THE IARC, THE COMMITTEE FOR OCCUPATIONAL EXPOSURE LIMITS OF THE JAPAN SOCIETY FOR OCCUPATIONAL HEALTH HAS MADE A PROPOSAL THAT IT IS TOO EARLY TO CLASSIFY THE CARCINOGENICITY OF TRI AS GROUP 2A AND THAT IT IS PROPER TO PROMOTE EXPOSURE CONTROL WITH THE CARCINOGENICITY BEING CLASSIFIED AS 2B FOR THE MOMENT. THERE ARE SPECIES DIFFERENCES IN TRI CARCINOGENICITY, PARTICULARLY BETWEEN RATS AND MICE. ALTHOUGH EXPERIMENTAL STUDIES HAVE FOUND NO EVIDENCE THAT TRI INDUCES LIVER CANCER IN RATS, THERE IS AMPLE EVIDENCE THAT TRI PROMOTES THE DEVELOPMENT OF LIVER CANCER IN MICE, PARTICULARLY IN B6C3F1 MICE. THE CARCINOGENICITY OF TRI IN THIS STRAIN OF MICE MAY BE BASED ON AN EPIGENETIC MECHANISM RATHER ON A GENOTOXIC MECHANISM AND THE LIVER CANCER MAY BE INDUCED ONLY AFTER TRI HAS BEEN INHALED FOR A LONG PERIOD OF TIME AT CONCENTRATIONS HIGH ENOUGH TO CAUSE CYTOTOXICITY. CONVERSELY, WITH NO REPORTS SHOWING TRI-INDUCED RENAL TUMORS IN MICE, THE POSSIBILITY HAS BEEN SUGGESTED THAT THIS CHEMICAL INDUCES SUCH TUMORS IN MALE RATS. THE SPECIES DIFFERENCES ARE MAINLY ACCOUNTED FOR BY DIFFERENCES IN THE METABOLISM OF TRI BETWEEN RATS AND MICE. FROM A GENERAL SURVEY OF THE LITERATURE, IT CAN BE CONCLUDED THAT TRI ITSELF IS NOT MUTAGENIC. HOWEVER, THE CONJUGATION OF TRI WITH GLUTATHIONE (GSH), A MINOR PATHWAY OF TRI METABOLISM, RESULTS IN MUTAGENIC METABOLITES IN THE KIDNEY OF RATS. THE ACUTE TOXICITY OF TRI IS NEUROTOXICITY BASED ON ITS ANESTHETIC ACTION. AN EXPOSURE TO EXTREMELY HIGH LEVELS OF TRI MAY CAUSE THE LIVER AND KIDNEY DISORDERS. REPEATED EXPOSURES TO HIGH LEVELS OF TRI MAY RESULT IN NEURO-, HEPATO-, AND/OR NEPHROTOXICITY. THE MAIN SYMPTOMS APPEARING AFTER CHRONIC EXPOSURE AT LOW LEVELS ARE NEUROLOGICAL CHANGES REPRESENTED BY SUBJECTIVE SYMPTOMS RELATING TO CENTRAL AND AUTONOMIC NERVOUS SYSTEMS, OR BY A LOWERED CONDUCTION VELOCITY OF THE NERVES OR A PROLONGED LATENCY OF THE NERVE RESPONSES. FOR THE PRESENT, IT IS REASONABLE TO USE THE NEUROLOGICAL FINDINGS FOR ESTABLISHING THE REFERENCE VALUES OF TRI FOR BOTH WORK AND GENERAL ENVIRONMENTS. A VALUE OF 25 PPM (135 MG/M3) IS PROPOSED AS A REFERENCE VALUE FOR WORK ENVIRONMENTS, AND 25-50 PPB (135-270 MICROGRAMS/M3) FOR THE GENERAL ENVIRONMENT (1/1,000 OF THE VALUE FOR WORK ENVIRONMENT).	1997	

2  5107  37 POLYCYSTIC OVARY SYNDROME: A BRAIN DISORDER CHARACTERIZED BY EATING PROBLEMS ORIGINATING DURING PUBERTY AND ADOLESCENCE. POLYCYSTIC OVARY SYNDROME (PCOS) IS AN ENDOCRINE CONDITION ASSOCIATED WITH REPRODUCTIVE AND PSYCHIATRIC DISORDERS, AND WITH OBESITY. EATING DISORDERS, SUCH AS BULIMIA AND RECURRENT DIETING, ARE ALSO LINKED TO PCOS. THEY CAN LEAD TO THE EPIGENETIC DYSREGULATION OF THE HYPOTHALAMIC-PITUITARY-GONADAL (HPG) AXIS, THEREBY IMPACTING ON OVARIAN FOLLICULOGENESIS. WE POSTULATE THAT PCOS IS INDUCED BY PSYCHOLOGICAL DISTRESS AND EPISODES OF OVEREATING AND/OR DIETING DURING PUBERTY AND ADOLESCENCE, WHEN BODY DISSATISFACTION AND EMOTIONAL DISTRESS ARE OFTEN PRESENT. WE PROPOSE THAT UPREGULATED ACTIVATION OF THE CENTRAL HPG AXIS DURING THIS PERIOD CAN BE EPIGENETICALLY ALTERED BY PSYCHOLOGICAL STRESSORS AND BY BULIMIA/RECURRENT DIETING, WHICH ARE COMMON DURING ADOLESCENCE AND WHICH CAN LEAD TO PCOS. THIS HYPOTHESIS IS BASED ON EVENTS THAT OCCUR DURING A LARGELY NEGLECTED STAGE OF FEMALE REPRODUCTIVE DEVELOPMENT. TO DATE, MOST RESEARCH INTO THE ORIGINS OF PCOS HAS FOCUSED ON THE PRENATAL INDUCTION OF THIS DISORDER, PARTICULARLY IN UTERO ANDROGENIZATION AND THE ROLE OF ANTI-MULLERIAN HORMONE. ESTABLISHING CAUSALITY IN OUR PERIPUBERTAL MODEL REQUIRES PROSPECTIVE COHORT STUDIES FROM INFANCY. MECHANISTIC STUDIES SHOULD CONSIDER THE ROLE OF THE GUT MICROBIOTA IN ADDITION TO THE EPIGENETIC REGULATION OF (NEURO) HORMONES. FINALLY, CLINICIANS SHOULD CONSIDER THE IMPORTANCE OF UNDERLYING CHRONIC PSYCHOLOGICAL DISTRESS AND EATING DISORDERS IN PCOS.	2020	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        
3  5355  32 REAC ANTALGIC NEURO MODULATION IN CHRONIC POST HERPETIC NEURALGIA. BACKGROUND: CHRONIC POST-HERPETIC NEURALGIA (CPHN) IS A SYMPTOMATIC CONDITION THAT AFFLICTS ADULTS AND ELDERLY INDIVIDUALS. THE CHRONICITY OF THIS SYMPTOMATOLOGY CAN BE CONDITIONED BY THE EPIGENETIC MODIFICATIONS INDUCED BY THE VIRUS ON THE PROCESSES OF NEUROTRANSMISSION AND SENSITIVITY TO PAIN. THE AIM OF THIS STUDY IS TO INVESTIGATE WHETHER MANIPULATING ENDOGENOUS BIOELECTRICAL ACTIVITY (EBA), RESPONSIBLE FOR NEUROTRANSMISSION PROCESSES AND CONTRIBUTING TO THE INDUCTION OF EPIGENETIC MODIFICATIONS, CAN ALLEVIATE PAIN SYMPTOMS. METHODS: THIS MANIPULATION WAS CARRIED OUT WITH THE ANTALGIC NEUROMODULATION (ANM) TREATMENT OF RADIOELECTRIC ASYMMETRIC CONVEYER (REAC) TECHNOLOGY. PAIN ASSESSMENT BEFORE AND AFTER TREATMENT WAS PERFORMED USING A NUMERICAL ANALOG SCALE (NAS) AND A SIMPLE DESCRIPTIVE SCALE (SDS). RESULTS: THE RESULTS OF THE ANALYSIS SHOWED AN OVER FOUR-POINT DECREASE IN NAS SCALE SCORE AND OVER ONE POINT DECREASE IN SDS SCALE SCORE, WITH A STATISTICAL SIGNIFICANCE FOR BOTH TESTS OF P < 0.005. CONCLUSIONS: THE RESULTS OBTAINED IN THIS STUDY DEMONSTRATE HOW REAC ANM MANIPULATION OF EBA CAN LEAD TO IMPROVEMENT IN EPIGENETICALLY CONDITIONED SYMPTOMS SUCH AS CPHN. THESE RESULTS SHOULD PROMPT FURTHER RESEARCH TO EXPAND KNOWLEDGE AND ENSURE OPTIMIZED THERAPEUTIC OUTCOMES.	2023	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        
4  3082  37 GENOME-WIDE REDISTRIBUTION OF MECP2 IN DORSAL ROOT GANGLIA AFTER PERIPHERAL NERVE INJURY. BACKGROUND: METHYL-CPG-BINDING PROTEIN 2 (MECP2), A PROTEIN WITH AFFINITY FOR METHYLATED CYTOSINES, IS CRUCIAL FOR NEURONAL DEVELOPMENT AND FUNCTION. MECP2 REGULATES GENE EXPRESSION THROUGH ACTIVATION, REPRESSION AND CHROMATIN REMODELING. MUTATIONS IN MECP2 CAUSE RETT SYNDROME, AND THESE PATIENTS DISPLAY IMPAIRED NOCICEPTION. WE OBSERVED AN INCREASE IN MECP2 EXPRESSION IN MOUSE DORSAL ROOT GANGLIA (DRG) AFTER PERIPHERAL NERVE INJURY. THE FUNCTIONAL IMPLICATION OF INCREASED MECP2 IS LARGELY UNKNOWN. TO IDENTIFY REGIONS OF THE GENOME BOUND BY MECP2 IN THE DRG AND THE CHANGES INDUCED BY NERVE INJURY, A CHROMATIN IMMUNOPRECIPITATION OF MECP2 FOLLOWED BY SEQUENCING (CHIP-SEQ) WAS PERFORMED 4 WEEKS AFTER SPARED NERVE INJURY (SNI). RESULTS: WHILE THE NUMBER OF BINDING SITES ACROSS THE GENOME REMAINED SIMILAR IN THE SNI MODEL AND SHAM CONTROL, SNI INDUCED THE REDISTRIBUTION OF MECP2 TO TRANSCRIPTIONALLY RELEVANT REGIONS. TO DETERMINE HOW DIFFERENTIAL BINDING OF MECP2 CAN AFFECT GENE EXPRESSION IN THE DRG, WE INVESTIGATED MMU-MIR-126, A MICRORNA LOCUS THAT HAD ENRICHED MECP2 BINDING IN THE SNI MODEL. ENRICHED MECP2 BINDING TO MIR-126 LOCUS AFTER NERVE INJURY REPRESSED MIR-126 EXPRESSION, AND THIS WAS NOT MEDIATED BY ALTERATIONS IN METHYLATION PATTERN AT THE MIR-126 LOCUS. DOWNREGULATION OF MIR-126 RESULTED IN THE UPREGULATION OF ITS TWO TARGET GENES DNMT1 AND VEGFA IN NEURO 2A CELLS AND IN SNI MODEL COMPARED TO CONTROL. THESE TARGET GENES WERE SIGNIFICANTLY DOWNREGULATED IN MECP2-NULL MICE COMPARED TO WILD-TYPE LITTERMATES, INDICATING A REGULATORY ROLE FOR MECP2 IN ACTIVATING DNMT1 AND VEGFA EXPRESSION. INTRATHECAL DELIVERY OF MIR-126 WAS NOT SUFFICIENT TO REVERSE NERVE INJURY-INDUCED MECHANICAL AND THERMAL HYPERSENSITIVITY, BUT DECREASED DNMT1 AND VEGFA EXPRESSION IN THE DRG. CONCLUSIONS: OUR STUDY SHOWS A REGULATORY ROLE FOR MECP2 IN THAT CHANGES IN GLOBAL REDISTRIBUTION CAN RESULT IN DIRECT AND INDIRECT MODULATION OF GENE EXPRESSION IN THE DRG. ALTERATIONS IN GENOME-WIDE BINDING OF MECP2 THEREFORE PROVIDE A MOLECULAR BASIS FOR A BETTER UNDERSTANDING OF EPIGENETIC REGULATION-INDUCED MOLECULAR CHANGES UNDERLYING NERVE INJURY.	2016	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   
5  4579  26 N(6)-METHYLADENOSINE METHYLASE METTL3 CONTRIBUTES TO NEUROPATHIC PAIN BY EPIGENETIC SILENCING OF MU OPIOID RECEPTOR. WE AIMED AT EXPLORING THE ROLE AND MECHANISM OF METTL3-MEDIATED M(6)A MODIFICATION IN NEUROPATHIC PAIN. MALE SPRAGUE-DAWLEY RATS WERE RANDOMLY DIVIDED INTO FOUR GROUPS: SHAM OPERATION GROUP (SHAM GROUP), CHRONIC CONSTRICTION INJURY (CCI) OF THE SCIATIC NERVE MODEL GROUP (NPP GROUP), INTRATHECAL INJECTION OF VIRUS DOWN-REGULATED METTL3 + CCI MODEL GROUP (M3 + NPP GROUP) AND INTRATHECAL INJECTION OF NEGATIVE CONTROL VIRUS + CCI MODEL GROUP (SCR + NPP GROUP). THE M3 + NPP GROUP AND THE SCR + NPP GROUP WERE INTRATHECALLY INJECTED WITH VIRUS NINETEEN DAYS BEFORE OPERATION. THE PAW WITHDRAWAL MECHANICAL THRESHOLDS AND PAW WITHDRAWAL LATENCY WERE RESPECTIVELY RECORDED ONE DAY BEFORE OPERATION, THREE DAYS, FIVE DAYS AND SEVEN DAYS AFTER OPERATION. THE RATS WERE SACRIFICED ON THE SEVENTH DAY AFTER OPERATION, AND THEIR SPINAL CORD TISSUES WERE TAKEN. THE FROZEN SECTIONS OF RATS WERE PERFORMED TO OBSERVE THE EXPRESSION OF GREEN FLUORESCENT PROTEIN OF THE VIRUS. THE METHYLATION LEVEL OF RNA, THE PROTEIN EXPRESSION OF M(6)A-RELATED ENZYME (METTL3) AND MU OPIOID RECEPTOR (MOR) IN SPINAL CORD TISSUES OF THE FOUR GROUPS WERE MEASURED. DOWNREGULATION OF METTL3 HAD NO EFFECT ON THE OVERALL METHYLATION LEVEL OF THE SPINAL CORD, BUT IT COULD REGULATE THE METHYLATION LEVEL OF THE OPRM1 GENE RNA ENCODING MOR, PARTIALLY RESTORE THE EXPRESSION OF MOR, AND RELIEVE PAIN IN RATS. IN THE PROCESS OF NPP, METTL3 MAY INHIBIT THE EXPRESSION OF MOR BY REGULATING THE METHYLATION LEVEL OF OPRM1 GENE RNA ENCODING MOR, AND ULTIMATELY PROMOTE THE OCCURRENCE AND DEVELOPMENT OF NPP.	2023	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  
6  2300  29 EPIGENETIC REGULATION OF BDNF EXPRESSION IN THE PRIMARY SENSORY NEURONS AFTER PERIPHERAL NERVE INJURY: IMPLICATIONS IN THE DEVELOPMENT OF NEUROPATHIC PAIN. BRAIN-DERIVED NEUROTROPHIC FACTOR (BDNF) IS KNOWN TO BE UP-REGULATED IN THE DORSAL ROOT GANGLION (DRG) AFTER PERIPHERAL NERVE INJURY, AND TO CONTRIBUTE TO NEUROPATHIC PAIN. HERE, WE FOUND THAT THERMAL HYPERALGESIA AND MECHANICAL ALLODYNIA AT DAY 7 POST-INJURY WERE INHIBITED ONLY WHEN ANTI-BDNF ANTIBODY WAS INTRATHECALLY ADMINISTRATED AT DAY 2 POST-INJURY. CONSISTENT WITH BEHAVIORAL RESULTS, WESTERN BLOT ANALYSIS SHOWED THAT THE EXPRESSION LEVELS OF BDNF PROTEIN IN THE SPINAL DORSAL HORN WERE MARKEDLY INDUCED DURING EARLY STAGE POST-INJURY. MOREOVER, THE MAXIMAL INCREASE IN BDNF MRNA EXPRESSION IN THE DRG WAS OBSERVED AT DAY 1 POST-INJURY, AND SIGNIFICANTLY ELEVATED LEVELS WERE SUSTAINED FOR AT LEAST 14 DAYS. FOUR OF FIVE BDNF MRNA TRANSCRIPTS WERE UP-REGULATED AFTER NERVE INJURY, AND THE MOST INDUCIBLE TRANSCRIPT WAS EXON I. USING A CHROMATIN IMMUNOPRECIPITATION (CHIP) ASSAY, WE FOUND THAT NERVE INJURY PROMOTES HISTONE H3 AND H4 ACETYLATION, TRANSCRIPTIONALLY ACTIVE MODIFICATIONS, AT BDNF PROMOTER I AT DAY 1 POST-INJURY, AND THE LEVELS OF HISTONE ACETYLATION REMAIN ELEVATED FOR AT LEAST 7 DAYS. TAKEN TOGETHER, OUR FINDINGS SUGGEST THAT AN INITIAL INCREASE IN BDNF EXON I EXPRESSION CONTROLLED BY EPIGENETIC MECHANISMS MIGHT HAVE A CRUCIAL ROLE IN THE DEVELOPMENT OF NEUROPATHIC PAIN.	2013	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       
7  3076  38 GENOME-WIDE EPIGENOMIC ANALYSES IN PATIENTS WITH NOCICEPTIVE AND NEUROPATHIC CHRONIC PAIN SUBTYPES REVEALS ALTERATIONS IN METHYLATION OF GENES INVOLVED IN THE NEURO-MUSCULOSKELETAL SYSTEM. NOCICEPTIVE PAIN INVOLVES THE ACTIVATION OF NOCICEPTORS WITHOUT DAMAGE TO THE NERVOUS SYSTEM, WHEREAS NEUROPATHIC PAIN IS RELATED TO AN ALTERATION IN THE CENTRAL OR PERIPHERAL NERVOUS SYSTEM. CHRONIC PAIN ITSELF AND THE TRANSITION FROM ACUTE TO CHRONIC PAIN MAY BE EPIGENETICALLY CONTROLLED. IN THIS CROSS-SECTIONAL STUDY, A GENOME-WIDE DNA METHYLATION ANALYSIS WAS PERFORMED USING THE BLOOD DNA REDUCED REPRESENTATION BISULFITE SEQUENCING (RRBS) TECHNIQUE. THREE PROSPECTIVE COHORTS INCLUDING 20 HEALTHY CONTROLS (CTL), 18 PATIENTS WITH CHRONIC NOCICEPTIVE PAIN (NOCI), AND 19 PATIENTS WITH CHRONIC NEUROPATHIC PAIN (NEURO) WERE COMPARED AT BOTH THE SINGLE CPG AND DIFFERENTIALLY METHYLATED REGION (DMR) LEVELS. GENES WITH DMRS WERE SEEN IN THE NOCI AND NEURO GROUPS BELONGED TO THE NEURO-MUSCULOSKELETAL SYSTEM AND DIFFERED BETWEEN NOCI AND NEURO PATIENTS. OUR RESULTS DEMONSTRATE THAT THE EPIGENETIC DISTURBANCES ACCOMPANYING NOCICEPTIVE PAIN ARE VERY DIFFERENT FROM THOSE ACCOMPANYING NEUROPATHIC PAIN. IN THE FORMER, AMONG OTHERS, THE EPIGENETIC DISTURBANCE OBSERVED WOULD AFFECT THE FUNCTION OF THE OPIOID ANALGESIC SYSTEM, WHEREAS IN THE LATTER IT WOULD AFFECT THAT OF THE GABAERGIC REWARD SYSTEM. THIS STUDY PRESENTS BIOLOGICAL FINDINGS THAT HELP TO CHARACTERIZE NOCI- AND NEURO-AFFECTED PATHWAYS AND OPENS THE POSSIBILITY OF DEVELOPING EPIGENETIC DIAGNOSTIC ASSAYS. PERSPECTIVE: OUR RESULTS HELP TO EXPLAIN THE VARIOUS BIOLOGICAL PATHWAYS MODIFICATIONS UNDERLYING THE DIFFERENT CLINICAL MANIFESTATIONS OF NOCICEPTIVE AND NEUROPATHIC PAINS. FURTHERMORE, THE NEW TARGETS IDENTIFIED IN OUR STUDY MIGHT HELP TO DISCOVER MORE SPECIFIC TREATMENTS FOR NOCICEPTIVE OR NEUROPATHIC PAINS.	2022	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    
8  1803  16 EFFECT OF PROLONGED EMOTIONAL AND PAIN STRESS ON THE CONTENT OF METHYLCYTOSINE-BINDING PROTEIN MECP2 IN NUCLEI OF HIPPOCAMPAL NEURONS IN RATS WITH DIFFERENT EXCITABILITY OF THE NERVOUS SYSTEM. IN RATS WITH LOW EXCITABILITY THRESHOLD OF THE NERVOUS SYSTEM DEMONSTRATING SIGNIFICANT AND PERSISTENT BEHAVIORAL DISORDERS UNDER STRESS CONDITIONS, THE CONTENT OF METHYLCYTOSINE-BINDING PROTEIN MECP2 IN NEURONAL NUCLEI OF HIPPOCAMPAL FIELD CA3 DECREASED OVER 2 WEEKS AFTER LONG-TERM EMOTIONAL AND PAIN STRESS. IT WAS HYPOTHESIZED THAT PROTEIN MECP2 TRIGGERS EPIGENETIC CHANGES IN DNA THAT UNDERLIE "STRESS MEMORY".	2006	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        
9   947  35 CHRONIC MEHG EXPOSURE MODIFIES THE HISTONE H3K4ME3 EPIGENETIC LANDSCAPE IN CAENORHABDITIS ELEGANS. METHYLMERCURY (MEHG) IS A PERSISTENT ENVIRONMENTAL POLLUTANT THAT OCCURS IN THE FOOD CHAIN, AT OCCUPATIONAL SITES, AND VIA MEDICAL PROCEDURES. EXPOSURE IN HUMANS AND ANIMAL MODELS RESULTS IN RENAL, NEURO, AND REPRODUCTIVE TOXICITIES. IN THIS STUDY, WE DEMONSTRATE THAT CHRONIC EXPOSURE TO MEHG (10MUM) CAUSES EPIGENETIC LANDSCAPE MODIFICATIONS OF HISTONE H3K4 TRIMETHYLATION (H3K4ME3) MARKS IN CAENORHABDITIS ELEGANS USING CHROMATIN IMMUNO-PRECIPITATION SEQUENCING (CHIP-SEQ). THE MODIFICATIONS CORRESPOND TO THE LOCATIONS OF 1467 GENES WITH ENHANCED AND 508 GENES WITH REDUCED SIGNALS. AMONG ENHANCED GENES ARE THOSE ENCODING GLUTATHIONE-S-TRANSFERASES, LIPOCALIN-RELATED PROTEIN AND A CUTICULAR COLLAGEN. CHIP-SEQ ENHANCEMENT OF THESE GENES WAS CONFIRMED WITH INCREASED MRNA EXPRESSION LEVELS REVEALED BY QRT-PCR. FURTHERMORE, WE OBSERVED ENHANCEMENT OF H3K4ME3 MARKS IN THESE GENES IN ANIMALS EXPOSED TO MEHG IN UTERO AND ASSAYED AT L4 STAGE. IN UTERO EXPOSURE ENHANCED MARKS WITHOUT ALTERATIONS IN MRNA EXPRESSION EXCEPT FOR THE LPR-5 GENE. FINALLY, KNOCKDOWN OF LIPOCALIN-RELATED PROTEIN GENE LPR-5, WHICH IS INVOLVED IN INTERCELLULAR SIGNALING, AND CUTICULAR COLLAGEN GENE DPY-7, STRUCTURAL COMPONENT OF THE CUTICLE, BY RNA INTERFERENCE (RNAI) RESULTED IN INCREASED LETHALITY OF ANIMALS AFTER MEHG EXPOSURE. OUR RESULTS PROVIDE NEW DATA ON THE EPIGENETIC LANDSCAPE CHANGES ELICITED BY MEHG EXPOSURE, AS WELL AS DESCRIBE A UNIQUE MODEL FOR STUDYING IN UTERO EFFECTS OF HEAVY METALS. TOGETHER, THESE FINDINGS MAY HELP TO UNDERSTAND THE TOXICOLOGICAL EFFECTS OF MEHG AT THE MOLECULAR LEVEL.	2017	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            
10   849  39 CHILDHOOD TRAUMATIZATION IS ASSOCIATED WITH DIFFERENCES IN TRPA1 PROMOTER METHYLATION IN FEMALE PATIENTS WITH MULTISOMATOFORM DISORDER WITH PAIN AS THE LEADING BODILY SYMPTOM. BACKGROUND: THE CONSTRUCT OF MULTISOMATOFORM DISORDER (MSD) IS A COMMON POINT OF REFERENCE FOR PATIENTS IN DIFFERENT SOMATIC AND PSYCHOSOMATIC SPECIALTIES AND THEREFORE USEFUL IN STUDYING LARGE WELL-CHARACTERIZED COHORTS OF A PROTOTYPE OF A SOMATOFORM DISORDER AND IN PARALLEL AS A FUNCTIONAL SOMATIC SYNDROME (FSS). THIS DISORDER IS CHARACTERIZED BY DISTRESSING AND FUNCTIONALLY DISABLING SOMATIC SYMPTOMS WITH CHRONIC PAIN AS THE MOST FREQUENT AND CLINICALLY RELEVANT COMPLAINT. PAIN IS PERCEIVED BY NOCICEPTIVE NERVE FIBERS AND TRANSFERRED THROUGH THE GENERATION OF ACTION POTENTIALS BY DIFFERENT RECEPTOR MOLECULES KNOWN TO DETERMINE PAIN SENSITIVITY IN PATHOPHYSIOLOGICAL PROCESSES. PREVIOUS STUDIES HAVE SHOWN THAT FOR THE TRANSIENT RECEPTOR POTENTIAL ANKYRIN 1 (TRPA1), RECEPTOR METHYLATION OF A PARTICULAR CPG DINUCLEOTIDE IN THE PROMOTER REGION IS INVERSELY ASSOCIATED WITH BOTH HEAT PAIN AND PRESSURE PAIN THRESHOLDS. IN THIS STUDY, WE HYPOTHESIZED THAT TRPA1 PROMOTER METHYLATION REGULATES PAIN SENSITIVITY OF PATIENTS WITH MULTISOMATOFORM DISORDER (MSD). A COHORT OF 151 PATIENTS WITH MSD AND 149 MATCHED HEALTHY VOLUNTEERS WERE EVALUATED USING QUANTITATIVE SENSORY TESTING, CLINICAL AND PSYCHOMETRIC ASSESSMENT, AND METHYLATION ANALYSIS USING DNA ISOLATED FROM WHOLE BLOOD. RESULTS: WE FOUND CPG -628 TO BE CORRELATED WITH MECHANICAL PAIN THRESHOLD AND CPG -411 TO BE CORRELATED WITH MECHANICAL PAIN THRESHOLD IN FEMALE VOLUNTEERS, I.E., HIGHER METHYLATION LEVELS LEAD TO HIGHER PAIN THRESHOLDS. A NOVEL FINDING IS THAT METHYLATION LEVELS WERE SIGNIFICANTLY DIFFERENT BETWEEN PATIENTS WITH NO AND SEVERE LEVELS OF CHILDHOOD TRAUMA. CPG METHYLATION ALSO CORRELATED WITH PSYCHOMETRIC ASSESSMENT OF PAIN AND PAIN LEVELS RATED ON A VISUAL ANALOG SCALE. CONCLUSION: OUR FINDINGS SUPPORT THE HYPOTHESIS THAT EPIGENETIC REGULATION OF TRPA1 PLAYS A ROLE IN MECHANICAL PAIN SENSITIVITIES IN HEALTHY VOLUNTEERS. THEY FURTHER PROVIDE EVIDENCE FOR THE POSSIBLE INFLUENCE OF CHILDHOOD TRAUMATIC EXPERIENCES ON THE EPIGENETIC REGULATION OF TRPA1 IN PATIENTS WITH MSD.	2019	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     
11  4617  36 NERVE INJURY-INDUCED CHRONIC PAIN IS ASSOCIATED WITH PERSISTENT DNA METHYLATION REPROGRAMMING IN DORSAL ROOT GANGLION. NERVE INJURY-INDUCED HYPERACTIVITY OF PRIMARY SENSORY NEURONS IN THE DORSAL ROOT GANGLION (DRG) CONTRIBUTES TO CHRONIC PAIN DEVELOPMENT, BUT THE UNDERLYING EPIGENETIC MECHANISMS REMAIN POORLY UNDERSTOOD. HERE WE DETERMINED GENOME-WIDE CHANGES IN DNA METHYLATION IN THE NERVOUS SYSTEM IN NEUROPATHIC PAIN. SPINAL NERVE LIGATION (SNL), BUT NOT PACLITAXEL TREATMENT, IN MALE SPRAGUE DAWLEY RATS INDUCED A CONSISTENT LOW-LEVEL HYPOMETHYLATION IN THE CPG SITES IN THE DRG DURING THE ACUTE AND CHRONIC PHASES OF NEUROPATHIC PAIN. DNA METHYLATION REMODELING IN THE DRG OCCURRED EARLY AFTER SNL AND PERSISTED FOR AT LEAST 3 WEEKS. SNL CAUSED DNA METHYLATION CHANGES AT 8% OF CPG SITES WITH PREVAILING HYPOMETHYLATION OUTSIDE OF CPG ISLANDS, IN INTRONS, INTERGENIC REGIONS, AND REPETITIVE SEQUENCES. IN CONTRAST, SNL CAUSED MORE GAINS OF METHYLATION IN THE SPINAL CORD AND PREFRONTAL CORTEX. THE DNA METHYLATION CHANGES IN THE INJURED DRGS RECAPITULATED DEVELOPMENTAL REPROGRAMMING AT THE NEONATAL STAGE. METHYLATION REPROGRAMMING WAS CORRELATED WITH INCREASED GENE EXPRESSION VARIABILITY. A DIET DEFICIENT IN METHYL DONORS INDUCED HYPOMETHYLATION AND PAIN HYPERSENSITIVITY. INTRATHECAL ADMINISTRATION OF THE DNA METHYLTRANSFERASE INHIBITOR RG108 CAUSED LONG-LASTING PAIN HYPERSENSITIVITY. DNA METHYLATION REPROGRAMMING IN THE DRG THUS CONTRIBUTES TO NERVE INJURY-INDUCED CHRONIC PAIN. RESTORING DNA METHYLATION MAY REPRESENT A NEW THERAPEUTIC APPROACH TO TREAT NEUROPATHIC PAIN.SIGNIFICANCE STATEMENT EPIGENETIC MECHANISMS ARE CRITICALLY INVOLVED IN THE TRANSITION FROM ACUTE TO CHRONIC PAIN AFTER NERVE INJURY. HOWEVER, GENOME-WIDE CHANGES IN DNA METHYLATION IN THE NERVOUS SYSTEM AND THEIR ROLES IN NEUROPATHIC PAIN DEVELOPMENT REMAIN UNCLEAR. HERE WE USED DIGITAL RESTRICTION ENZYME ANALYSIS OF METHYLATION TO QUANTITATIVELY DETERMINE GENOME-WIDE DNA METHYLATION CHANGES CAUSED BY NERVE INJURY. WE SHOWED THAT NERVE INJURY CAUSED DNA METHYLATION CHANGES AT 8% OF CPG SITES WITH PREVAILING HYPOMETHYLATION OUTSIDE OF CPG ISLANDS IN THE DORSAL ROOT GANGLION. REDUCING DNA METHYLATION INDUCED PAIN HYPERSENSITIVITY, WHEREAS INCREASING DNA METHYLATION ATTENUATED NEUROPATHIC PAIN. THESE FINDINGS EXTEND OUR UNDERSTANDING OF THE EPIGENETIC MECHANISM OF CHRONIC NEUROPATHIC PAIN AND SUGGEST NEW STRATEGIES TO TREAT NERVE INJURY-INDUCED CHRONIC PAIN.	2018	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              
12  1320  31 DEMETHYLATION REGULATION OF BDNF GENE EXPRESSION IN DORSAL ROOT GANGLION NEURONS IS IMPLICATED IN OPIOID-INDUCED PAIN HYPERSENSITIVITY IN RATS. REPEATED ADMINISTRATION OF MORPHINE MAY RESULT IN OPIOID-INDUCED HYPERSENSITIVITY (OIH), WHICH INVOLVES ALTERED EXPRESSION OF NUMEROUS GENES, INCLUDING BRAIN-DERIVED NEUROTROPHIC FACTOR (BDNF) IN DORSAL ROOT GANGLION (DRG) NEURONS. YET, IT REMAINS UNCLEAR HOW BDNF EXPRESSION IS INCREASED IN DRG NEURONS AFTER REPEATED MORPHINE TREATMENT. DNA METHYLATION IS AN IMPORTANT MECHANISM OF EPIGENETIC CONTROL OF GENE EXPRESSION. IN THE CURRENT STUDY, WE HYPOTHESIZED THAT THE DEMETHYLATION REGULATION OF CERTAIN BDNF GENE PROMOTERS IN DRG NEURONS MAY CONTRIBUTE TO THE DEVELOPMENT OF OIH. REAL-TIME RT-PCR WAS USED TO ASSESS CHANGES IN THE MRNA TRANSCRIPTION LEVELS OF MAJOR BDNF EXONS INCLUDING EXON I, II, IV, VI, AS WELL AS TOTAL BDNF MRNA IN DRGS FROM RATS AFTER REPEATED MORPHINE ADMINISTRATION. THE LEVELS OF EXON IV AND TOTAL BDNF MRNA WERE SIGNIFICANTLY UPREGULATED BY REPEATED MORPHINE ADMINISTRATION, AS COMPARED TO THAT IN SALINE CONTROL GROUP. FURTHER, ELISA ARRAY AND IMMUNOCYTOCHEMISTRY STUDY REVEALED A ROBUST UPREGULATION OF BDNF PROTEIN EXPRESSION IN DRG NEURONS AFTER REPEATED MORPHINE EXPOSURE. CORRESPONDINGLY, THE METHYLATION LEVELS OF BDNF EXON IV PROMOTER SHOWED A SIGNIFICANT DOWNREGULATION BY MORPHINE TREATMENT. IMPORTANTLY, INTRATHECAL ADMINISTRATION OF A BDNF ANTIBODY, BUT NOT CONTROL IGG, SIGNIFICANTLY INHIBITED MECHANICAL HYPERSENSITIVITY THAT DEVELOPED IN RATS AFTER REPEATED MORPHINE TREATMENT. CONVERSELY, INTRATHECAL ADMINISTRATION OF AN INHIBITOR OF DNA METHYLATION, 5-AZA-2'-DEOXYCYTIDINE (5-AZA-DC) MARKEDLY UPREGULATED THE BDNF PROTEIN EXPRESSION IN DRG NEURONS AND ENHANCED THE MECHANICAL ALLODYNIA AFTER REPEATED MORPHINE EXPOSURE. TOGETHER, OUR FINDINGS SUGGEST THAT DEMETHYLATION REGULATION OF BDNF GENE PROMOTER MAY BE IMPLICATED IN THE DEVELOPMENT OF OIH THROUGH EPIGENETIC CONTROL OF BDNF EXPRESSION IN DRG NEURONS.	2016	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       
13   325  40 ALLELE-SPECIFIC DNA METHYLATION LEVEL OF FKBP5 IS ASSOCIATED WITH POST-TRAUMATIC STRESS DISORDER. BACKGROUND: FK506-BINDING PROTEIN 5 (FKBP5) BINDS TO GLUCOCORTICOID RECEPTORS AND MODULATES GLUCOCORTICOID SENSITIVITY. THE FKBP5 GENE HAS BEEN IMPLICATED IN THE DYSREGULATION OF HUMAN STRESS RESPONSES, CONTRIBUTING TO THE RISK AND TREATMENT RESPONSE OF STRESS-RELATED DISORDERS. THE PRESENT STUDY EXAMINED WHETHER EPIGENETIC CHANGES IN FKBP5 ARE ASSOCIATED WITH CHRONIC POST-TRAUMATIC STRESS DISORDER (PTSD) STATUS IN THE CONTEXT OF FKBP5 GENETIC VARIATION (RS1360780 POLYMORPHISM) AMONG MALE VETERANS EXPOSED TO COMBAT TRAUMA. METHODS: KOREAN MALE VETERANS WHO SERVED ON ACTIVE DUTY DURING THE VIETNAM WAR WERE CATEGORIZED INTO 2 GROUPS: WITH PTSD (N = 123) AND WITHOUT PTSD (N = 116). THE GENOTYPE OF FKBP5 RS1360780 AND DNA METHYLATION LEVELS OF TWO CPG SITES AT THE FKBP5 INTRON 7 REGION WERE ASSESSED IN PERIPHERAL BLOOD. ANALYSIS OF COVARIANCE WAS PERFORMED TO EXAMINE MAIN AND INTERACTION EFFECTS OF PTSD STATUS AND FKBP5 GENOTYPE ON FKBP5 DNA METHYLATION LEVEL, WITH AGE, TRAUMA LEVELS, AND ALCOHOL USE AS COVARIATES. RESULTS: A SIGNIFICANT MAIN EFFECT OF FKBP5 RS1360780 AND PTSD AND AN INTERACTION EFFECT BETWEEN GENOTYPE AND PTSD STATUS WERE FOUND ON MEAN FKBP5 DNA METHYLATION LEVEL. THE T ALLELE OF RS1360780 WAS ASSOCIATED WITH LOWER FKBP5 METHYLATION LEVEL. IN ADDITION, THE PTSD GROUP SHOWED SIGNIFICANTLY HIGHER METHYLATION THAN DID THE NON-PTSD GROUP AMONG VETERANS CARRYING THE RISK T ALLELE (N = 96), WHILE NO GROUP DIFFERENCE WAS OBSERVED ON METHYLATION LEVELS AMONG VETERANS WITH THE CC GENOTYPE (N = 143). AMONG VETERANS CARRYING THE T ALLELE, FKBP5 METHYLATION LEVELS WERE POSITIVELY CORRELATED WITH THE SEVERITY OF PTSD SYMPTOMS. CONCLUSIONS: THE PRESENT STUDY DEMONSTRATED DIFFERENT FKBP5 METHYLATION LEVELS IN PTSD DEPENDING ON FKBP5 GENETIC VARIATION AMONG VETERANS EXPOSED TO COMBAT TRAUMA. THE PRESENT FINDING SUGGESTS THAT THE GENETIC AND EPIGENETIC MODULATION OF FKBP5 IS INVOLVED IN THE PATHOPHYSIOLOGY OF PTSD. FURTHER LONGITUDINAL RESEARCH INVOLVING PEOPLE EXPOSED TO TRAUMA IS REQUIRED TO UNDERSTAND CAUSAL RELATIONSHIPS OF FKBP5 IN THE DEVELOPMENT AND RECOVERY OF PTSD.	2019	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          
14  2321  29 EPIGENETIC REGULATION OF GENES THAT MODULATE CHRONIC STRESS-INDUCED VISCERAL PAIN IN THE PERIPHERAL NERVOUS SYSTEM. BACKGROUND & AIMS: CHRONIC STRESS ALTERS THE HYPOTHALAMIC-PITUITARY-ADRENAL AXIS, INCREASES GUT MOTILITY, AND INCREASES THE PERCEPTION OF VISCERAL PAIN. WE INVESTIGATED WHETHER EPIGENETIC MECHANISMS REGULATE CHRONIC STRESS-INDUCED VISCERAL PAIN IN THE PERIPHERAL NERVOUS SYSTEMS OF RATS. METHODS: MALE RATS WERE SUBJECTED TO 1 HOUR OF WATER AVOIDANCE STRESS EACH DAY, OR GIVEN DAILY SUBCUTANEOUS INJECTIONS OF CORTICOSTERONE, FOR 10 CONSECUTIVE DAYS. L4-L5 AND L6-S2 DORSAL ROOT GANGLIA (DRG) WERE COLLECTED AND COMPARED BETWEEN STRESSED AND CONTROL RATS (PLACED FOR 1 HOUR EACH DAY IN A TANK WITHOUT WATER). LEVELS OF CANNABINOID RECEPTOR 1 (CNR1), DNA (CYTOSINE-5-)-METHYLTRANSFERASE 1 (DNMT1), TRANSIENT RECEPTOR POTENTIAL VANILLOID TYPE 1 (TRPV1), AND EP300 WERE KNOCKED DOWN IN DRG NEURONS IN SITU WITH SMALL INTERFERING RNAS. WE MEASURED DNA METHYLATION AND HISTONE ACETYLATION AT GENES ENCODING THE GLUCOCORTICOID RECEPTOR (NR3C1), CNR1, AND TRPV1. VISCERAL PAIN WAS MEASURED IN RESPONSE TO COLORECTAL DISTENTION. RESULTS: CHRONIC STRESS WAS ASSOCIATED WITH INCREASED METHYLATION OF THE NR3C1 PROMOTER AND REDUCED EXPRESSION OF THIS GENE IN L6-S2, BUT NOT L4-L5, DRGS. STRESS ALSO WAS ASSOCIATED WITH UP-REGULATION IN DNMT1-ASSOCIATED METHYLATION OF THE CNR1 PROMOTER AND DOWN-REGULATION OF GLUCOCORTICOID-RECEPTOR-MEDIATED EXPRESSION OF CNR1 IN L6-S2, BUT NOT L4-L5, DRGS. CONCURRENTLY, CHRONIC STRESS INCREASED EXPRESSION OF THE HISTONE ACETYLTRANSFERASE EP300 AND INCREASED HISTONE ACETYLATION AT THE TRPV1 PROMOTER AND EXPRESSION OF THE TRPV1 RECEPTOR IN L6-S2 DRG NEURONS. KNOCKDOWN OF DNMT1 AND EP300 IN L6-S2 DRG NEURONS OF RATS REDUCED DNA METHYLATION AND HISTONE ACETYLATION, RESPECTIVELY, AND PREVENTED CHRONIC STRESS-INDUCED INCREASES IN VISCERAL PAIN. CONCLUSIONS: CHRONIC STRESS INCREASES DNA METHYLATION AND HISTONE ACETYLATION OF GENES THAT REGULATE VISCERAL PAIN SENSATION IN THE PERIPHERAL NERVOUS SYSTEM OF RATS. BLOCKING EPIGENETIC REGULATORY PATHWAYS IN SPECIFIC REGIONS OF THE SPINAL CORD MIGHT BE DEVELOPED TO TREAT PATIENTS WITH CHRONIC ABDOMINAL PAIN.	2015	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 
15  6418  39 THE TEMPORAL EXPRESSION OF CIRCULATING MICRORNAS AFTER ACUTE EXPERIMENTAL PAIN IN HUMANS. BACKGROUND: MICRORNAS (MIRNAS) CAN MODULATE SEVERAL BIOLOGICAL SYSTEMS, INCLUDING THE PAIN SYSTEM. THIS STUDY AIMED TO EVALUATE THE TEMPORAL EXPRESSION OF CIRCULATING MIRNAS IN THE PLASMA OF HEALTHY VOLUNTEERS AS A MARKER FOR EPIGENETIC CHANGES BEFORE AND AFTER AN ACUTE, EXPERIMENTAL, PAIN PROVOCATION BY INTRAMUSCULAR HYPERTONIC SALINE INJECTION. METHODS: TWENTY VOLUNTEERS WERE RANDOMLY ALLOCATED INTO TWO GROUPS AND RECEIVED EITHER HYPERTONIC (PAIN) OR ISOTONIC (CONTROL) SALINE INJECTION IN THE FIRST DORSAL INTEROSSEOUS MUSCLE OF THEIR DOMINANT HAND. PAIN INTENSITY WAS CONTINUOUSLY RECORDED FOR 20 MINUTES AFTER INJECTION ON A VAS SCALE FROM 0 TO 100 (0 INDICATES NO PAIN AND 100 THE WORST IMAGINABLE PAIN). BLOOD SAMPLES WERE TAKEN AT BASELINE, 30 MINUTES, 3 HOURS, AND 24 HOURS POST-INJECTION, AND PLASMA WAS SEPARATED. MIRNA EXTRACTS WERE USED FOR RNA SEQUENCING WITH THE ILLUMINA NEXTSEQ PLATFORM. MIRNA TRANSCRIPTS WERE COMPARED BETWEEN THE PAIN AND THE NO-PAIN, CONTROL GROUP AT EVERY TIME POINT. SIGNIFICANT DIFFERENCES WERE CONSIDERED WHEN FOLDS WERE >2 AND THE FALSE DISCOVERY RATE WAS P < 0.05. RESULTS: AFTER 30 MINUTES, 4 MIRNAS WERE SIGNIFICANTLY ALTERED IN THE PAIN GROUP COMPARED TO CONTROLS, WHICH INCREASED TO 24 AFTER 3 HOURS AND TO 42 AFTER 24 HOURS FROM BASELINE (P < 0.0001). TWO MIRNAS WERE CONSISTENTLY UPREGULATED THROUGHOUT THE EXPERIMENT. ENRICHMENT ANALYSIS SHOWED SIGNIFICANT MIRNAS INVOLVED IN BRAIN PERCEPTION OF PAIN, BRAIN SIGNALLING AND RESPONSE TO STIMULI. CONCLUSIONS: THIS EXPLORATORY STUDY IS THE FIRST TO REPORT ON THE TEMPORAL EXPRESSION OF CIRCULATING MIRNAS AFTER AN ACUTE, HUMAN EXPERIMENTAL MUSCLE PAIN MODEL. SIGNIFICANCE: THIS EXPLORATORY STUDY EVALUATED THE TEMPORAL PROFILE OF CIRCULATING MIRNAS IN THE PLASMA OF HEALTHY SUBJECTS AFTER ACUTE EXPERIMENTAL PAIN. SEVERAL MIRNAS WERE ALTERED IN SUBJECTS AT THE TIMES OF FOLLOW-UP AFTER THE ACUTE PAIN MODEL WHEN COMPARED TO CONTROLS. MIRNAS PREVIOUSLY ASSOCIATED WITH PAIN PROCESSES WERE ALTERED IN THE PAIN GROUP. OUR RESULTS, BY SHOWING THE FAST AND PROLONGED MODIFICATIONS OF MIRNA ELICITED BY THE ACUTE EXPERIMENTAL PAIN MODEL, ADD NEW PERSPECTIVES TO THE TOPIC OF EPIGENETICS AND PAIN.	2023	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              
16   812  39 CHANGES IN DNA METHYLATION PROFILES OF MYALGIC ENCEPHALOMYELITIS/CHRONIC FATIGUE SYNDROME PATIENTS REFLECT SYSTEMIC DYSFUNCTIONS. BACKGROUND: MYALGIC ENCEPHALOMYELITIS/CHRONIC FATIGUE SYNDROME (ME/CFS) IS A LIFELONG DEBILITATING DISEASE WITH A COMPLEX PATHOLOGY NOT YET CLEARLY DEFINED. SUSCEPTIBILITY TO ME/CFS INVOLVES GENETIC PREDISPOSITION AND EXPOSURE TO ENVIRONMENTAL FACTORS, SUGGESTING AN EPIGENETIC ASSOCIATION. EPIGENETIC STUDIES WITH OTHER ME/CFS COHORTS HAVE USED ARRAY-BASED TECHNOLOGY TO IDENTIFY DIFFERENTIALLY METHYLATED INDIVIDUAL SITES. CHANGES IN RNA QUANTITIES AND PROTEIN ABUNDANCE HAVE BEEN DOCUMENTED IN OUR PREVIOUS INVESTIGATIONS WITH THE SAME ME/CFS COHORT USED FOR THIS STUDY. RESULTS: DNA FROM A WELL-CHARACTERISED NEW ZEALAND COHORT OF 10 ME/CFS PATIENTS AND 10 AGE-/SEX-MATCHED HEALTHY CONTROLS WAS ISOLATED FROM PERIPHERAL BLOOD MONONUCLEAR (PBMC) CELLS, AND USED TO GENERATE REDUCED GENOME-SCALE DNA METHYLATION MAPS USING REDUCED REPRESENTATION BISULPHITE SEQUENCING (RRBS). THE SEQUENCING DATA WERE ANALYSED UTILISING THE DMAP ANALYSIS PIPELINE TO IDENTIFY DIFFERENTIALLY METHYLATED FRAGMENTS, AND THE METHYLKIT PIPELINE WAS USED TO QUANTIFY METHYLATION DIFFERENCES AT INDIVIDUAL CPG SITES. DMAP IDENTIFIED 76 DIFFERENTIALLY METHYLATED FRAGMENTS AND METHYLKIT IDENTIFIED 394 DIFFERENTIALLY METHYLATED CYTOSINES THAT INCLUDED BOTH HYPER- AND HYPO-METHYLATION. FOUR CLUSTERS WERE IDENTIFIED WHERE DIFFERENTIALLY METHYLATED DNA FRAGMENTS OVERLAPPED WITH OR WERE WITHIN CLOSE PROXIMITY TO MULTIPLE DIFFERENTIALLY METHYLATED INDIVIDUAL CYTOSINES. THESE CLUSTERS IDENTIFIED REGULATORY REGIONS FOR 17 PROTEIN ENCODING GENES RELATED TO METABOLIC AND IMMUNE ACTIVITY. ANALYSIS OF DIFFERENTIALLY METHYLATED GENE BODIES (EXONS/INTRONS) IDENTIFIED 122 UNIQUE GENES. COMPARISON WITH OTHER STUDIES ON PBMCS FROM ME/CFS PATIENTS AND CONTROLS WITH ARRAY TECHNOLOGY SHOWED 59% OF THE GENES IDENTIFIED IN THIS STUDY WERE ALSO FOUND IN ONE OR MORE OF THESE STUDIES. FUNCTIONAL PATHWAY ENRICHMENT ANALYSIS IDENTIFIED 30 ASSOCIATED PATHWAYS. THESE INCLUDED IMMUNE, METABOLIC AND NEUROLOGICAL-RELATED FUNCTIONS DIFFERENTIALLY REGULATED IN ME/CFS PATIENTS COMPARED TO THE MATCHED HEALTHY CONTROLS. CONCLUSIONS: MAJOR DIFFERENCES WERE IDENTIFIED IN THE DNA METHYLATION PATTERNS OF ME/CFS PATIENTS THAT CLEARLY DISTINGUISHED THEM FROM THE HEALTHY CONTROLS. OVER HALF FOUND IN GENE BODIES WITH RRBS IN THIS STUDY HAD BEEN IDENTIFIED IN OTHER ME/CFS STUDIES USING THE SAME CELLS BUT WITH ARRAY TECHNOLOGY. WITHIN THE ENRICHED FUNCTIONAL IMMUNE, METABOLIC AND NEUROLOGICAL PATHWAYS, A NUMBER OF ENRICHED NEUROTRANSMITTER AND NEUROPEPTIDE REACTOME PATHWAYS HIGHLIGHTED A DISTURBED NEUROLOGICAL PATHOPHYSIOLOGY WITHIN THE PATIENT GROUP.	2020	
                                                                                                                                                                                                                                                                                                   
17  3810  26 INTRATHECAL 5-AZACYTIDINE INHIBITS GLOBAL DNA METHYLATION AND METHYL- CPG-BINDING PROTEIN 2 EXPRESSION AND ALLEVIATES NEUROPATHIC PAIN IN RATS FOLLOWING CHRONIC CONSTRICTION INJURY. THE PATHOGENESIS OF NEUROPATHIC PAIN REMAINS LARGELY UNKNOWN. EPIGENETIC MECHANISMS MAY PLAY A MAJOR ROLE IN REGULATING EXPRESSION OF PRO- OR ANTINOCICEPTIVE GENES. DNA METHYLATION IS A MAJOR EPIGENETIC MECHANISM IN VERTEBRATES, AND METHYL- CPG-BINDING PROTEIN 2 (MECP2) IS DIRECTLY INVOLVED IN METHYLATION-MEDIATED GENE SILENCING. TO DETERMINE HOW CHANGES IN GLOBAL DNA METHYLATION AND MECP2 EXPRESSION OCCUR FOLLOWING CHRONIC CONSTRICTION INJURY (CCI) AND HOW REPRESSION OF DNA METHYLATION AFFECTS THESE CHANGES AND ATTENUATES NEUROPATHIC PAIN, WE USED INTRATHECAL 5-AZACYTIDINE, A DNA METHYLTRANSFERASE INHIBITOR, IN CCI RATS. RATS RECEIVED 0.9% SALINE OR 5-AZACYTIDINE (10MUMOL.D(-1)) VIA SPINAL INJECTION ONCE DAILY FROM DAY 3 TO DAY 14 AFTER CCI SURGERY. GLOBAL DNA METHYLATION AND MECP2 EXPRESSION INCREASED IN THE SPINAL CORD IN CCI RATS ON DAY 14 AFTER CCI SURGERY. MECHANICAL ALLODYNIA AND THERMAL HYPERALGESIA INDUCED BY CCI WERE ATTENUATED BY INTRATHECAL 5-AZACYTIDINE FROM DAY 5 TO DAY 14 AFTER CCI SURGERY. THE INCREASES IN GLOBAL DNA METHYLATION AND MECP2 EXPRESSION IN THE SPINAL CORD IN CCI RATS WERE ALSO SIGNIFICANTLY INHIBITED BY INTRATHECAL 5-AZACYTIDINE. THESE RESULTS DEMONSTRATE THAT INCREASED GLOBAL DNA METHYLATION AND MECP2 EXPRESSION IN THE SPINAL CORD AFTER NERVE DAMAGE MAY PLAY AN IMPORTANT ROLE IN NEUROPATHIC PAIN. 5-AZACYTIDINE SHOWS POTENTIAL FOR TREATING NEUROPATHIC PAIN.	2011	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 
18  2207  40 EPIGENETIC MODIFICATIONS AND GLUCOCORTICOID SENSITIVITY IN MYALGIC ENCEPHALOMYELITIS/CHRONIC FATIGUE SYNDROME (ME/CFS). BACKGROUND: MYALGIC ENCEPHALOMYELITIS/CHRONIC FATIGUE SYNDROME (ME/CFS) IS A DEBILITATING IDIOPATHIC DISEASE CHARACTERIZED BY UNEXPLAINED FATIGUE THAT FAILS TO RESOLVE WITH SUFFICIENT REST. DIAGNOSIS IS BASED ON A LIST OF SYMPTOMS AND EXCLUSION OF OTHER FATIGUE-RELATED HEALTH CONDITIONS. DESPITE A HETEROGENEOUS PATIENT POPULATION, IMMUNE AND HYPOTHALAMIC-PITUITARY-ADRENAL (HPA) AXIS FUNCTION DIFFERENCES, SUCH AS ENHANCED NEGATIVE FEEDBACK TO GLUCOCORTICOIDS, ARE RECURRING FINDINGS IN ME/CFS STUDIES. EPIGENETIC MODIFICATIONS, SUCH AS CPG METHYLATION, ARE KNOWN TO REGULATE LONG-TERM PHENOTYPIC DIFFERENCES AND PREVIOUS WORK BY OUR GROUP FOUND DNA METHYLOME DIFFERENCES IN ME/CFS, HOWEVER THE RELATIONSHIP BETWEEN DNA METHYLOME MODIFICATIONS, CLINICAL AND FUNCTIONAL CHARACTERISTICS ASSOCIATED WITH ME/CFS HAS NOT BEEN EXAMINED. METHODS: WE EXAMINED THE DNA METHYLOME IN PERIPHERAL BLOOD MONONUCLEAR CELLS (PBMCS) OF A LARGER COHORT OF FEMALE ME/CFS PATIENTS USING THE ILLUMINA HUMANMETHYLATION450 BEADCHIP ARRAY. IN PARALLEL TO THE DNA METHYLOME ANALYSIS, WE INVESTIGATED IN VITRO GLUCOCORTICOID SENSITIVITY DIFFERENCES BY STIMULATING PBMCS WITH PHYTOHAEMAGGLUTININ AND SUPPRESSED GROWTH WITH DEXAMETHASONE. WE EXPLORED DNA METHYLATION DIFFERENCES USING BISULFITE PYROSEQUENCING AND STATISTICAL PERMUTATION. LINEAR REGRESSION WAS IMPLEMENTED TO DISCOVER EPIGENOMIC REGIONS ASSOCIATED WITH SELF-REPORTED QUALITY OF LIFE AND NETWORK ANALYSIS OF GENE ONTOLOGY TERMS TO BIOLOGICALLY CONTEXTUALIZE RESULTS. RESULTS: WE DETECTED 12,608 DIFFERENTIALLY METHYLATED SITES BETWEEN ME/CFS PATIENTS AND HEALTHY CONTROLS PREDOMINANTLY LOCALIZED TO CELLULAR METABOLISM GENES, SOME OF WHICH WERE ALSO RELATED TO SELF-REPORTED QUALITY OF LIFE HEALTH SCORES. AMONG ME/CFS PATIENTS, GLUCOCORTICOID SENSITIVITY WAS ASSOCIATED WITH DIFFERENTIAL METHYLATION AT 13 LOCI. CONCLUSIONS: OUR RESULTS INDICATE DNA METHYLATION MODIFICATIONS IN CELLULAR METABOLISM IN ME/CFS DESPITE A HETEROGENEOUS PATIENT POPULATION, IMPLICATING THESE PROCESSES IN IMMUNE AND HPA AXIS DYSFUNCTION IN ME/CFS. MODIFICATIONS TO EPIGENETIC LOCI ASSOCIATED WITH DIFFERENCES IN GLUCOCORTICOID SENSITIVITY MAY BE IMPORTANT AS BIOMARKERS FOR FUTURE CLINICAL TESTING. OVERALL, THESE FINDINGS ALIGN WITH RECENT ME/CFS WORK THAT POINT TOWARDS IMPAIRMENT IN CELLULAR ENERGY PRODUCTION IN THIS PATIENT POPULATION.	2017	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       
19  5200  28 PRENATAL MATERNAL STRESS PREDICTS METHYLATION OF GENES REGULATING THE HYPOTHALAMIC-PITUITARY-ADRENOCORTICAL SYSTEM IN MOTHERS AND NEWBORNS IN THE DEMOCRATIC REPUBLIC OF CONGO. EXPOSURE TO STRESS EARLY IN LIFE PERMANENTLY SHAPES ACTIVITY OF THE HYPOTHALAMIC-PITUITARY-ADRENOCORTICAL (HPA) AXIS AND THE BRAIN. PRENATALLY, GLUCOCORTICOIDS PASS THROUGH THE PLACENTA TO THE FETUS WITH POSTNATAL IMPACTS ON BRAIN DEVELOPMENT, BIRTH WEIGHT (BW), AND HPA AXIS FUNCTIONING. LITTLE IS KNOWN ABOUT THE BIOLOGICAL MECHANISMS BY WHICH PRENATAL STRESS AFFECTS POSTNATAL FUNCTIONING. THIS STUDY ADDRESSES THIS GAP BY EXAMINING THE EFFECT OF CHRONIC STRESS AND TRAUMATIC WAR-RELATED STRESS ON EPIGENETIC CHANGES IN FOUR KEY GENES REGULATING THE HPA AXIS IN NEONATAL CORD BLOOD, PLACENTA, AND MATERNAL BLOOD: CRH, CRHBP, NR3C1, AND FKBP5. PARTICIPANTS WERE 24 MOTHER-NEWBORN DYADS IN THE CONFLICT-RIDDEN REGION OF THE EASTERN DEMOCRATIC REPUBLIC OF CONGO. BW DATA WERE COLLECTED AT DELIVERY AND MATERNAL INTERVIEWS WERE CONDUCTED TO ASSESS CULTURALLY RELEVANT CHRONIC AND WAR-RELATED STRESSORS. CHRONIC STRESS AND WAR TRAUMA HAD WIDESPREAD EFFECTS ON HPA AXIS GENE METHYLATION, WITH SIGNIFICANT EFFECTS OBSERVED AT TRANSCRIPTION FACTOR BINDING (TFB) SITES IN ALL TARGET GENES TESTED. SOME CHANGES IN METHYLATION WERE UNIQUE TO CHRONIC OR WAR STRESS, WHEREAS OTHERS WERE OBSERVED ACROSS BOTH STRESSOR TYPES. MOREOVER, STRESS EXPOSURES IMPACTED MATERNAL AND FETAL TISSUES DIFFERENTLY, SUPPORTING THEORETICAL MODELS THAT STRESS IMPACTS VARY ACCORDING TO LIFE PHASE. METHYLATION IN SEVERAL NR3C1 AND CRH CPG SITES, ALL LOCATED AT TFB SITES, WAS ASSOCIATED WITH BW. THESE FINDINGS SUGGEST THAT PRENATAL STRESS EXPOSURE IMPACTS DEVELOPMENT VIA EPIGENETIC CHANGES IN HPA AXIS GENES.	2016	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         
20  1161  44 CONTINUOUS DEVELOPMENTAL AND EARLY LIFE TRICHLOROETHYLENE EXPOSURE PROMOTED DNA METHYLATION ALTERATIONS IN POLYCOMB PROTEIN BINDING SITES IN EFFECTOR/MEMORY CD4(+) T CELLS. TRICHLOROETHYLENE (TCE) IS AN INDUSTRIAL SOLVENT AND DRINKING WATER POLLUTANT ASSOCIATED WITH CD4(+) T CELL-MEDIATED AUTOIMMUNITY. IN OUR MOUSE MODEL, DISCONTINUATION OF TCE EXPOSURE DURING ADULTHOOD AFTER DEVELOPMENTAL EXPOSURE DID NOT PREVENT IMMUNOTOXICITY. TO DETERMINE WHETHER PERSISTENT EFFECTS WERE LINKED TO EPIGENETIC CHANGES WE CONDUCTED WHOLE GENOME REDUCED REPRESENTATION BISULFITE SEQUENCING (RRBS) TO EVALUATE METHYLATION OF CPG SITES IN AUTOSOMAL CHROMOSOMES IN ACTIVATED EFFECTOR/MEMORY CD4(+) T CELLS. FEMALE MRL+/+ MICE WERE EXPOSED TO VEHICLE CONTROL OR TCE IN THE DRINKING WATER FROM GESTATION UNTIL ~37 WEEKS OF AGE [POSTNATAL DAY (PND) 259]. IN A SUBSET OF MICE, TCE EXPOSURE WAS DISCONTINUED AT ~22 WEEKS OF AGE (PND 154). AT PND 259, RRBS ASSESSMENT REVEALED MORE GLOBAL METHYLATION CHANGES IN THE CONTINUOUS EXPOSURE GROUP VS. THE DISCONTINUOUS EXPOSURE GROUP. A MAJORITY OF THE DIFFERENTIALLY METHYLATED CPG REGIONS (DMRS) ACROSS PROMOTERS, ISLANDS, AND REGULATORY ELEMENTS WERE HYPERMETHYLATED (~90%). HOWEVER, CONTINUOUS DEVELOPMENTAL TCE EXPOSURE ALTERED THE METHYLATION OF 274 CPG SITES IN PROMOTERS AND CPG ISLANDS. IN CONTRAST, ONLY 4 CPG ISLAND REGIONS WERE DIFFERENTIALLY METHYLATED (HYPERMETHYLATED) IN THE DISCONTINUOUS GROUP. INTERESTINGLY, 2 OF THESE 4 SITES WERE ALSO HYPERMETHYLATED IN THE CONTINUOUS EXPOSURE GROUP, AND BOTH OF THESE ISLAND REGIONS ARE ASSOCIATED WITH LYSINE 27 ON HISTONE H3 (H3K27) INVOLVED IN POLYCOMB COMPLEX-DEPENDENT TRANSCRIPTIONAL REPRESSION VIA H3K27 TRI-METHYLATION. CPG SITES WERE OVERLAPPED WITH THE OPEN REGULATORY ANNOTATION DATABASE. UNLIKE THE DISCONTINUOUS GROUP, CONTINUOUS TCE TREATMENT RESULTED IN 129 DMRS INCLUDING 12 UNIQUE TRANSCRIPTION FACTORS AND REGULATORY ELEMENTS; 80% OF WHICH WERE ENRICHED FOR ONE OR MORE POLYCOMB GROUP (PCG) PROTEIN BINDING REGIONS (I.E., SUZ12, EZH2, JARID2, AND MTF2). PATHWAY ANALYSIS OF THE DMRS INDICATED THAT TCE PRIMARILY ALTERED THE METHYLATION OF GENES ASSOCIATED WITH REGULATION OF CELLULAR METABOLISM AND CELL SIGNALING. THE RESULTS DEMONSTRATED THAT CONTINUOUS DEVELOPMENTAL EXPOSURE TO TCE DIFFERENTIALLY METHYLATED BINDING SITES OF PCG PROTEINS IN EFFECTOR/MEMORY CD4(+) CELLS. THERE WERE MINIMAL YET POTENTIALLY BIOLOGICALLY SIGNIFICANT EFFECTS THAT OCCURRED WHEN EXPOSURE WAS DISCONTINUED. THESE RESULTS POINT TOWARD A NOVEL MECHANISM BY WHICH CHRONIC DEVELOPMENTAL TCE EXPOSURE MAY ALTER TERMINALLY DIFFERENTIATED CD4(+) T CELL FUNCTION IN ADULTHOOD.	2019