1 2123 173 EPIGENETIC IMPACTS OF STRESS PRIMING OF THE NEUROINFLAMMATORY RESPONSE TO SARIN SURROGATE IN MICE: A MODEL OF GULF WAR ILLNESS. BACKGROUND: GULF WAR ILLNESS (GWI) IS AN ARCHETYPAL, MEDICALLY UNEXPLAINED, CHRONIC CONDITION CHARACTERISED BY PERSISTENT SICKNESS BEHAVIOUR AND NEUROIMMUNE AND NEUROINFLAMMATORY COMPONENTS. AN ESTIMATED 25-32% OF THE OVER 900,000 VETERANS OF THE 1991 GULF WAR FULFIL THE REQUIREMENTS OF A GWI DIAGNOSIS. IT HAS BEEN HYPOTHESISED THAT THE HIGH PHYSICAL AND PSYCHOLOGICAL STRESS OF COMBAT MAY HAVE INCREASED VULNERABILITY TO IRREVERSIBLE ACETYLCHOLINESTERASE (ACHE) INHIBITORS LEADING TO A PRIMING OF THE NEUROIMMUNE SYSTEM. A NUMBER OF STUDIES HAVE LINKED HIGH LEVELS OF PSYCHOPHYSIOLOGICAL STRESS AND TOXICANT EXPOSURES TO EPIGENETIC MODIFICATIONS THAT REGULATE GENE EXPRESSION. RECENT RESEARCH IN A MOUSE MODEL OF GWI HAS SHOWN THAT PRE-EXPOSURE WITH THE STRESS HORMONE CORTICOSTERONE (CORT) CAUSES AN INCREASE IN EXPRESSION OF SPECIFIC CHEMOKINES AND CYTOKINES IN RESPONSE TO DIISOPROPYL FLUOROPHOSPHATE (DFP), A SARIN SURROGATE AND IRREVERSIBLE ACHE INHIBITOR. METHODS: C57BL/6J MICE WERE EXPOSED TO CORT FOR 4 DAYS, AND EXPOSED TO DFP ON DAY 5, BEFORE SACRIFICE 6 H LATER. THE TRANSCRIPTOME WAS EXAMINED USING RNA-SEQ, AND THE EPIGENOME WAS EXAMINED USING REDUCED REPRESENTATION BISULFITE SEQUENCING AND H3K27AC CHIP-SEQ. RESULTS: WE SHOW TRANSCRIPTIONAL, HISTONE MODIFICATION (H3K27AC) AND DNA METHYLATION CHANGES IN GENES RELATED TO THE IMMUNE AND NEURONAL SYSTEM, POTENTIALLY RELEVANT TO NEUROINFLAMMATORY AND COGNITIVE SYMPTOMS OF GWI. FURTHER EVIDENCE SUGGESTS ALTERED PROPORTIONS OF MYELINATING OLIGODENDROCYTES IN THE FRONTAL CORTEX, PERHAPS CONNECTED TO WHITE MATTER DEFICITS SEEN IN GWI SUFFERERS. CONCLUSIONS: OUR FINDINGS MAY REFLECT THE EARLY CHANGES WHICH OCCURRED IN GWI VETERANS, AND WE OBSERVE ALTERATIONS IN SEVERAL PATHWAYS ALTERED IN GWI SUFFERERS. THESE CLOSE LINKS TO CHANGES SEEN IN VETERANS WITH GWI INDICATES THAT THIS MODEL REFLECTS THE ENVIRONMENTAL EXPOSURES RELATED TO GWI AND MAY PROVIDE A MODEL FOR BIOMARKER DEVELOPMENT AND TESTING FUTURE TREATMENTS. 2018 2 1988 50 EPIGENETIC ANALYSIS IN A MURINE GENETIC MODEL OF GULF WAR ILLNESS. OF THE NEARLY 1 MILLION MILITARY PERSONNEL WHO PARTICIPATED IN THE 1990-1991 GULF WAR, BETWEEN 25% AND 35% BECAME ILL WITH WHAT NOW IS REFERRED TO AS GULF WAR ILLNESS (GWI) BY THE DEPARTMENT OF DEFENSE. SYMPTOMS VARIED FROM GASTROINTESTINAL DISTRESS TO LETHARGY, MEMORY LOSS, INABILITY TO CONCENTRATE, DEPRESSION, RESPIRATORY, AND REPRODUCTIVE PROBLEMS. THE SYMPTOMS HAVE PERSISTED FOR 30 YEARS IN THOSE AFFLICTED BUT THE BASIS OF THE ILLNESS REMAINS LARGELY UNKNOWN. NERVE AGENTS AND OTHER CHEMICAL EXPOSURES IN THE WAR ZONE HAVE BEEN IMPLICATED BUT THE LONG-TERM EFFECTS OF THESE ACUTE EXPOSURES HAVE LEFT FEW IF ANY IDENTIFIABLE SIGNATURES. THE MAJOR AIM OF THIS STUDY IS TO ELUCIDATE THE POSSIBLE GENOMIC BASIS FOR THE PERSISTENCE OF SYMPTOMS, ESPECIALLY OF THE NEUROLOGICAL AND BEHAVIORAL EFFECTS. TO ADDRESS THIS, WE PERFORMED A WHOLE GENOME EPIGENETIC ANALYSIS OF THE PROPOSED CAUSE OF GWI, VIZ., EXPOSURE TO ORGANOPHOSPHATE NEUROTOXICANTS COMBINED WITH HIGH CIRCULATING GLUCOCORTICOIDS IN TWO INBRED MOUSE STRAINS, C57BL/6J AND DBA/2J. THE ANIMALS RECEIVED CORTICOSTERONE IN THEIR DRINKING WATER FOR 7 DAYS FOLLOWED BY INJECTION OF DIISOPROPYLFLUOROPHOSPHATE, A NERVE AGENT SURROGATE. SIX WEEKS AFTER DFP INJECTION, THE ANIMALS WERE EUTHANIZED AND MEDIAL PREFRONTAL CORTEX HARVESTED FOR GENOME-WIDE DNA METHYLATION ANALYSIS USING HIGH-THROUGHPUT SEQUENCING. WE OBSERVED 67 DIFFERENTIALLY METHYLATED GENES, NOTABLY AMONG THEM, TTLL7, AKR1C14, SLC44A4, AND RUSC2, ALL RELATED TO DIFFERENT SYMPTOMS OF GWI. OUR RESULTS SUPPORT PROOF OF PRINCIPLE OF GENETIC DIFFERENCES IN THE CHRONIC EFFECTS OF GWI-RELATED EXPOSURES AND MAY REVEAL WHY THE DISEASE HAS PERSISTED IN MANY OF THE NOW AGING GULF WAR VETERANS. 2023 3 107 46 A REVIEW OF PRE-CLINICAL MODELS FOR GULF WAR ILLNESS. GULF WAR ILLNESS (GWI) IS A CHRONIC MULTISYMPTOMATIC DISORDER THAT AFFLICTS OVER 1/3RD OF THE 1991 GW VETERANS. IT SPANS MULTIPLE BODILY SYSTEMS AND PRESENTS ITSELF AS A SYNDROME EXHIBITING DIVERSE SYMPTOMS INCLUDING FATIGUE, DEPRESSION, MOOD, AND MEMORY AND CONCENTRATION DEFICITS, MUSCULOSKELETAL PAIN AND GASTROINTESTINAL DISTRESS IN GW VETERANS. THE ETIOLOGY OF GWI IS COMPLEX AND MANY FACTORS, INCLUDING CHEMICAL, PHYSIOLOGICAL, AND ENVIRONMENTAL STRESSORS PRESENT IN THE GW ARENA, HAVE BEEN IMPLICATED FOR ITS DEVELOPMENT. IT HAS BEEN OVER 30 YEARS SINCE THE END OF THE GW BUT, GWI HAS BEEN PERSISTENT IN SUFFERING VETERANS WHO ARE ALSO DEALING WITH PAUCITY OF EFFECTIVE TREATMENTS. THE MULTIFACTORIAL ASPECT OF GWI ALONG WITH GENETIC HETEROGENEITY AND LACK OF AVAILABLE DATA SURROUNDING WAR-TIME EXPOSURES HAVE PROVED TO BE CHALLENGING IN DEVELOPING PRE-CLINICAL MODELS OF GWI. DESPITE THIS, OVER A DOZEN GWI ANIMAL MODELS EXIST IN THE LITERATURE. IN THIS ARTICLE, FOLLOWING A BRIEF DISCUSSION OF GW HISTORY, GWI DEFINITIONS, AND PROBABLE CAUSES FOR ITS PATHOGENESIS, WE WILL EXPAND UPON VARIOUS EXPERIMENTAL MODELS USED IN GWI LABORATORY RESEARCH. THESE ANIMAL MODELS WILL BE DISCUSSED IN THE CONTEXT OF THEIR ATTEMPTS AT MIMICKING GW-RELATED EXPOSURES WITH REGARDS TO THE VARIATIONS IN CHEMICAL COMBINATIONS, DOSES, AND FREQUENCY OF EXPOSURES. WE WILL DISCUSS THEIR ADVANTAGES AND LIMITATIONS IN MODELING GWI FOLLOWED BY A DISCUSSION OF BEHAVIORAL AND MOLECULAR FINDINGS IN THESE MODELS. THE MECHANISTIC DATA OBTAINED FROM THESE PRECLINICAL STUDIES HAVE OFFERED MULTIPLE MOLECULAR PATHWAYS INCLUDING CHRONIC INFLAMMATION, MITOCHONDRIAL DYSFUNCTION, OXIDATIVE STRESS, LIPID DISTURBANCES, CALCIUM HOMEOSTATIC ALTERATIONS, CHANGES IN GUT MICROBIOTA, AND EPIGENETIC MODIFICATIONS, AMONGST OTHERS FOR EXPLAINING GWI DEVELOPMENT AND ITS PERSISTENCE. FINALLY, THESE FINDINGS HAVE ALSO INFORMED US ON NOVEL DRUGGABLE TARGETS IN GWI. WHILE, IT HAS BEEN DIFFICULT TO CONCEIVE A SINGLE PRE-CLINICAL MODEL THAT COULD EXPRESS ALL THE GWI SIGNS AND EXHIBIT BIOLOGICAL COMPLEXITY REFLECTIVE OF THE CLINICAL PRESENTATION IN GWI, ANIMAL MODELS HAVE BEEN CRITICAL FOR IDENTIFYING MOLECULAR UNDERPINNINGS OF GWI AND EVALUATING TREATMENT STRATEGIES FOR GWI. 2021 4 5451 40 REPROGRAMMING CELLS FROM GULF WAR VETERANS INTO NEURONS TO STUDY GULF WAR ILLNESS. GULF WAR ILLNESS (GWI), WHICH AFFLICTS AT LEAST 25% OF VETERANS WHO SERVED IN THE 1990-1991 WAR IN THE PERSIAN GULF, IS THOUGHT TO BE CAUSED BY DEPLOYMENT EXPOSURES TO VARIOUS NEUROTOXICANTS, INCLUDING PESTICIDES, ANTI-NERVE GAS PILLS, AND LOW-LEVEL NERVE AGENTS INCLUDING SARIN/CYCLOSARIN. GWI IS A MULTISYMPTOM DISORDER CHARACTERIZED BY FATIGUE, JOINT PAIN, COGNITIVE PROBLEMS, AND GASTROINTESTINAL COMPLAINTS. THE MOST PROMINENT SYMPTOMS OF GWI (MEMORY PROBLEMS, POOR ATTENTION/CONCENTRATION, CHRONIC HEADACHES, MOOD ALTERATIONS, AND IMPAIRED SLEEP) SUGGEST THAT THE DISEASE PRIMARILY AFFECTS THE CNS. DEVELOPMENT OF URGENTLY NEEDED TREATMENTS DEPENDS ON EXPERIMENTAL MODELS APPROPRIATE FOR TESTING MECHANISTIC HYPOTHESES AND FOR SCREENING THERAPEUTIC COMPOUNDS. RODENT MODELS HAVE BEEN USEFUL THUS FAR, BUT ARE LIMITED BY THEIR INABILITY TO ASSESS THE CONTRIBUTION OF GENETIC OR EPIGENETIC BACKGROUND TO THE DISEASE, AND BECAUSE DISEASE-VULNERABLE PROTEINS AND PATHWAYS MAY BE DIFFERENT IN HUMANS RELATIVE TO RODENTS. AS OF YET, NO POSTMORTEM TISSUE FROM THE VETERANS HAS BECOME AVAILABLE FOR RESEARCH. WE ARE MOVING FORWARD WITH A PARADIGM SHIFT IN THE STUDY OF GWI, WHICH UTILIZES CONTEMPORARY STEM CELL TECHNOLOGY TO CONVERT SOMATIC CELLS FROM GULF WAR VETERANS INTO PLURIPOTENT CELL LINES THAT CAN BE DIFFERENTIATED INTO VARIOUS CELL TYPES, INCLUDING NEURONS, GLIA, MUSCLE, OR OTHER RELEVANT CELL TYPES. SUCH CELL LINES ARE IMMORTAL AND WILL BE A RESOURCE FOR GWI RESEARCHERS TO PURSUE MECHANISTIC HYPOTHESES AND THERAPEUTICS. 2017 5 336 42 ALTERATIONS IN DNA METHYLATION STATUS ASSOCIATED WITH GULF WAR ILLNESS. GULF WAR ILLNESS (GWI) AFFECTS ABOUT 25% OF PERSIAN GULF VETERANS WITH A CLUSTER OF CHRONIC SYMPTOMS, INCLUDING IMMUNE DYSFUNCTION AND NEUROLOGICAL ISSUES. RECENT STUDIES IMPLICATE GENE EXPRESSION CHANGES IN IMMUNE FUNCTION TO BE ASSOCIATED WITH GWI. SINCE DNA METHYLATION CAN REGULATE SUCH CHANGES IN GENE EXPRESSION, AND DISRUPTION OF DNA METHYLATION PATTERN IS IMPLICATED IN VARIOUS IMMUNE AND NEUROLOGICAL DISEASES, WE AIMED TO STUDY THE DNA METHYLATION PATTERNS IN PERIPHERAL BLOOD MONONUCLEAR CELLS FROM GWI PATIENTS. GLOBAL DNA METHYLATION LEVELS WERE SIMILAR IN GWI PATIENTS AND CONTROLS. HOWEVER, THE GENOME-WIDE MICROARRAY TECHNOLOGY DETECTED 10,767 DIFFERENTIALLY METHYLATED CPG SITES ACROSS GENE REGULATORY ELEMENTS AND WITHIN CODING REGIONS. APPROXIMATELY 88% OF THEM WERE HYPERMETHYLATED IN GWI PATIENTS. THE SEPARATE ANALYSIS FOUND 776 DIFFERENTIALLY METHYLATED GENE PROMOTERS (DMP), WHICH WERE PREDOMINANTLY HYPERMETHYLATED. PYROSEQUENCING VALIDATION CONFIRMED MICROARRAY RESULTS. FUNCTIONAL ANALYSIS REVEALED THAT MAJORITY OF THE DMPS BELONGED TO GENES RESPONSIBLE FOR METABOLISM AND IMMUNE SYSTEM. THIS IS THE FIRST PILOT HUMAN STUDY CHARACTERIZING GENOME-WIDE EPIGENETIC CHANGES ASSOCIATED WITH GWI. IT SUGGESTS A SIGNIFICANT CONTRIBUTION OF EPIGENETIC DYSFUNCTION IN GWI. MOREOVER, IT SUPPORTS THE DYSREGULATION OF IMMUNE FUNCTION IN GWI. LASTLY, IT SUGGESTS STUDIES WITH THE LARGER COHORT TO VALIDATE OUR FINDINGS. 2019 6 90 55 A PILOT REVERSE VIRTUAL SCREENING STUDY SUGGESTS TOXIC EXPOSURES CAUSED LONG-TERM EPIGENETIC CHANGES IN GULF WAR ILLNESS. GULF WAR ILLNESS (GWI) IS A CHRONIC ILLNESS THAT AFFECTS UPWARD OF 32% OF DEPLOYED VETERANS TO THE 1991 GULF WAR (GW). THE SYMPTOMS ARE MEDICALLY UNEXPLAINED, RANGING ACROSS COGNITIVE DEFICITS, FATIGUE, GASTROINTESTINAL PROBLEMS, AND MUSCULOSKELETAL PAIN. RESEARCH INDICATES THAT CHEMICAL WARFARE AGENTS PLAY A KEY ROLE IN THE ONSET AND PROGRESSION OF GWI. THE KHAMISIYAH AMMUNITION STORAGE THAT HOUSED CHEMICAL WARFARE AGENTS SUCH AS SARIN, AN ACETYLCHOLINESTERASE (ACHE) INHIBITOR, WAS DEMOLISHED DURING THE GW, RELEASING TOXICANTS INTO THE ATMOSPHERE AFFECTING DEPLOYED TROOPS. EXPOSURE TO OTHER CHEMICAL AGENTS SUCH AS PYRIDOSTIGMINE BROMIDE, N,N-DIETHYL-M-TOLUAMIDE, PERMETHRIN AND CHLORPYRIFOS, WERE ALSO PREVALENT DURING THE WAR. THESE ADDITIONAL CHEMICAL AGENTS HAVE ALSO BEEN SHOWN TO INHIBIT ACHE. ACHE INHIBITION INDUCES AN ACETYLCHOLINE BUILD-UP, DISRUPTING SIGNALS BETWEEN NERVES AND MUSCLES, WHICH IN HIGH DOSES LEADS TO ASPHYXIATION. LITTLE IS KNOWN ABOUT LOW DOSE EXPOSURE. AS BIOACTIVE COMPOUNDS TEND TO INTERACT WITH MULTIPLE PROTEINS WITH VARIOUS PHYSIOLOGICAL EFFECT, WE AIMED TO IDENTIFY OTHER POTENTIAL SHARED TARGETS TO UNDERSTAND THE EXTENT IN WHICH THESE CHEMICALS COULD LEAD TO GWI. WE FOLLOWED A REVERSE SCREENING APPROACH WHERE EACH CHEMICAL IS COMPUTATIONALLY DOCKED TO A LIBRARY OF PROTEIN TARGETS. THE PROGRAMS PHARMMAPPER AND TARGETNET WERE USED FOR THIS PURPOSE, AND FURTHER ANALYSES WERE CONDUCTED TO MARK SIGNIFICANT CHANGES IN PARTICIPANTS WITH GWI. PREVIOUSLY PUBLISHED WORK ON DNA METHYLATION STATUS IN GWI WAS REANALYZED FOCUSING SPECIFICALLY ON THE PREDICTED SHARED TARGETS INDICATING SIGNIFICANT CHANGES IN DNA METHYLATION OF THE ASSOCIATED GENES. OUR FINDINGS THUS SUGGEST THAT EXPOSURE TO GWI-RELATED AGENTS MAY CONVERGE ON SIMILAR TARGETS WITH ROLES IN INFLAMMATION, NEUROTRANSMITTER AND LIPID METABOLISM, AND DETOXIFICATION WHICH MAY HAVE IMPACTS ON NEURODEGENERATIVE-LIKE DISEASE AND OXIDATIVE STRESS IN VETERANS WITH GWI. 2022 7 3980 48 LONG-TERM EPIGENETIC ALTERATIONS IN A RAT MODEL OF GULF WAR ILLNESS. GULF WAR ILLNESS (GWI) IS A CHRONIC, MULTISYMPTOM ILLNESS THAT AFFECTS 25% OF THE 700,000 US VETERANS DEPLOYED TO THE PERSIAN GULF DURING THE 1990-1991 GULF WAR. CENTRAL NERVOUS SYSTEM IMPAIRMENTS ARE AMONG THE MOST COMMON SYMPTOMS REPORTED, INCLUDING MEMORY DYSFUNCTION AND DEPRESSION. AFTER 25 YEARS, THE DIAGNOSIS REMAINS ELUSIVE, USEFUL TREATMENTS ARE LACKING, AND THE CAUSE IS POORLY UNDERSTOOD, ALTHOUGH EXPOSURES TO PYRIDOSTIGMINE BROMIDE (PB) AND PESTICIDES ARE CONSISTENTLY IDENTIFIED TO BE AMONG THE STRONGEST RISK FACTORS. EPIGENETIC CHANGES INCLUDING ALTERED MICRORNA (MIRNA) EXPRESSION AND DNA METHYLATION PLAY AN IMPORTANT ROLE IN LEARNING, MEMORY, AND EMOTION REGULATION AND HAVE BEEN IMPLICATED IN VARIOUS NEUROLOGICAL DISORDERS. IN THIS STUDY, WE USED AN ESTABLISHED RAT MODEL OF GWI TO DETERMINE WHETHER 1) CHRONIC ALTERATIONS IN MIRNA EXPRESSION AND GLOBAL DNA METHYLATION AND DNA HYDROXYMETHYLATION ARE MECHANISMS INVOLVED IN THE PATHOBIOLOGY OF GWI, AND 2) PLASMA EXOSOME SMALL RNAS MAY SERVE AS POTENTIAL NONINVASIVE BIOMARKERS OF THIS DEBILITATING DISEASE. ONE YEAR AFTER A 28-DAY EXPOSURE REGIMEN OF PB, DEET (N,N-DIETHYL-3-METHYLBENZAMIDE), PERMETHRIN, AND MILD STRESS, EXPRESSION OF 84 MATURE MIRNAS AND GLOBAL 5-METHYLCYTOSINE (5MC) AND 5-HYDROXYMETHYLCYTOSINE (5HMC) CONTENT WERE ANALYZED IN THE BRAINS OF GWI RATS AND VEHICLE CONTROLS BY PCR ARRAY AND ENZYME-LINKED IMMUNOSORBENT ASSAY, RESPECTIVELY. PLASMA EXOSOME RNA NEXT-GENERATION SEQUENCING ANALYSIS WAS PERFORMED IN POOLED SAMPLES TO DISCOVER POTENTIAL NONINVASIVE BIOMARKERS. WE FOUND THAT COMBINED EXPOSURE TO LOW DOSES OF GW-RELATED CHEMICALS AND MILD STRESS CAUSED EPIGENETIC MODIFICATIONS IN THE BRAIN THAT PERSISTED ONE YEAR AFTER EXPOSURE, INCLUDING INCREASED EXPRESSION OF MIR-124-3P AND MIR-29B-3P IN THE HIPPOCAMPUS AND REGIONAL ALTERATIONS IN GLOBAL 5MC AND 5HMC CONTENT. GW-RELEVANT EXPOSURES ALSO INDUCED THE DIFFERENTIAL EXPRESSION OF TWO PIWI-INTERACTING RNAS (PIRNAS) IN CIRCULATION (PIR-007899 AND PIR-019162). RESULTS FROM THIS STUDY IMPLICATE A ROLE FOR EPIGENETIC ALTERATIONS IN GWI. EVALUATION OF THE DIAGNOSTIC POTENTIAL OF PLASMA EXOSOME RNAS IN VETERANS WITH GWI IS WARRANTED. 2016 8 6108 40 THE ENRICHED ENVIRONMENT AMELIORATES CHRONIC UNPREDICTABLE MILD STRESS-INDUCED DEPRESSIVE-LIKE BEHAVIORS AND COGNITIVE IMPAIRMENT BY ACTIVATING THE SIRT1/MIR-134 SIGNALING PATHWAY IN HIPPOCAMPUS. BACKGROUND: CHRONIC UNPREDICTABLE MILD STRESS (CUMS) IS AN IMPORTANT RISK FACTOR FOR DEPRESSION AND COGNITIVE DEFICITS IN HUMANS. ENRICHED ENVIRONMENT (EE) SHOWED A BENEFICIAL EFFECT ON DEPRESSION AND COGNITION BY ENHANCING BRAIN DERIVED NEUROTROPHIC FACTOR (BDNF) EXPRESSION AND SYNAPTIC PLASTICITY. HOWEVER, IT IS STILL NOT CLEARLY UNDERSTOOD WHETHER AN EPIGENETIC MECHANISM IS INVOLVED IN THE BDNF MODULATION AND SYNAPTIC PLASTICITY THAT OCCURS AFTER EE TREATMENT FOR THE DEPRESSIVE-LIKE BEHAVIORS AND COGNITIVE DEFICITS ELICITED BY CUMS. IN THIS STUDY, WE INVESTIGATED THE POSSIBLE MECHANISM OF THE NEUROPROTECTIVE EFFECT OF EE. METHODS: ALL RATS WERE EXPOSED TO THE 5-WEEK CUMS PROCEDURE EXCEPT THE CONTROL GROUP. AFTER CUMS PROCEDURE, SOME RATS WERE STEREOTAXICALLY INJECTED WITH SIRT1 PHARMACOLOGIC INHIBITOR EX527 OR SIRT1 KNOCKING DOWN LENTIVIRUS (SH-SIRT1) IN THE HIPPOCAMPUS FOLLOWED BY EE TREATMENT FOR 3 WEEKS. OTHER RATS WERE DIRECTLY SUBJECTED TO EE TREATMENT WITHOUT STEREOTAXIC INJECTION. BEHAVIORAL TESTS WERE USED TO APPRAISE DEPRESSION AND COGNITION AFTER EE TREATMENT. THEN EPIGENETIC MOLECULES, SYNAPTIC PROTEINS, DENDRITIC SPINE DENSITY AND BRANCHES, AND SYNAPTIC MORPHOLOGY OF THE DORSAL HIPPOCAMPUS WERE DETERMINED. RESULTS: WE FOUND THAT CUMS INDUCED DEPRESSIVE-LIKE BEHAVIORS INCLUDING DECREASED SUCROSE PREFERENCE RATIO, PROLONGED IMMOBILITY AND REDUCED LOCOMOTOR AND EXPLORATORY ACTIVITY; COGNITIVE DEFICITS INCLUDING SPATIAL LEARNING AND MEMORY IMPAIRMENT; REDUCED DENDRITIC SPINE DENSITY AND NUMBER OF BRANCHES; THINNED POSTSYNAPTIC DENSITY; DOWNREGULATED SIRT1/MICRORNA-134 PATHWAY, DECREASED BDNF AND SYNAPTIC PROTEINS INCLUDING SYNAPTOPHYSIN (SYN) AND POSTSYNAPTIC DENSITY PROTEIN 95 (PSD95) EXPRESSION IN THE HIPPOCAMPUS. HOWEVER, THE CUMS-INDUCED DEPRESSIVE-LIKE BEHAVIORS, COGNITIVE DEFICITS, DENDRITIC SPINE DENSITY AND BRANCH NUMBER REDUCTION, POSTSYNAPTIC DENSITY THINNING, SIRT1/MICRORNA-134 PATHWAY DOWNREGULATION, BDNF AND SYNAPTIC PROTEINS REDUCTION, INCLUDING SYNAPTOPHYSIN (SYN) AND POSTSYNAPTIC DENSITY PROTEIN 95 (PSD95), WERE REVERSED BY EE TREATMENT. HOWEVER, DEPRESSIVE-LIKE BEHAVIORS AND COGNITIVE DEFICITS WERE OBSERVED AGAIN IN RATS SUBJECTED TO STEREOTAXIC INJECTION WITH EX527 OR SH-SIRT1. FURTHERMORE, THIS STUDY ALSO FOUND THAT SIRT1/MICRORNA-134 REGULATES THE DOWNSTREAM MOLECULES BDNF, AND THE SYNAPTIC PROTEINS SYN AND PSD95 IN PRIMARY CULTURED HIPPOCAMPAL NEURONS. CONCLUSIONS: THIS STUDY PROVIDES EVIDENCE FOR THE NEUROPROTECTIVE ROLE OF EE ON DEPRESSION AND COGNITIVE DEFICITS BY ACTIVATING THE SIRT1/MICRORNA-134 PATHWAY, WHICH ACCOUNTS FOR THE REGULATION OF SYNAPTIC PROTEINS, INCLUDING BDNF, PSD95 AND SYN, DENDRITIC REMODELING AND ULTRASTRUCTURE CHANGES OF SYNAPSES IN THE HIPPOCAMPUS. 2019 9 949 38 CHRONIC METHAMPHETAMINE TREATMENT REDUCES THE EXPRESSION OF SYNAPTIC PLASTICITY GENES AND CHANGES THEIR DNA METHYLATION STATUS IN THE MOUSE BRAIN. METHAMPHETAMINE (METH) IS A HIGHLY ADDICTIVE PSYCHOSTIMULANT THAT MAY CAUSE LONG-LASTING SYNAPTIC DYSFUNCTION AND ABNORMAL GENE EXPRESSION. WE AIMED TO EXPLORE THE DIFFERENTIAL EXPRESSION OF SYNAPTIC PLASTICITY GENES IN CHRONIC METH-TREATED MOUSE BRAIN. WE USED THE RT(2) PROFILER PCR ARRAY AND THE REAL-TIME QUANTITATIVE PCR TO CHARACTERIZE DIFFERENTIALLY EXPRESSED SYNAPTIC PLASTICITY GENES IN THE FRONTAL CORTEX AND THE HIPPOCAMPUS OF CHRONIC METH-TREATED MICE COMPARED WITH NORMAL SALINE-TREATED MICE. WE FURTHER USED PYROSEQUENCING TO ASSESS DNA METHYLATION CHANGES IN THE CPG REGION OF THE FIVE IMMEDIATE EARLY GENES (IEGS) IN CHRONIC METH-TREATED MOUSE BRAIN. WE DETECTED SIX DOWNREGULATED GENES IN THE FRONTAL CORTEX AND THE HIPPOCAMPUS OF CHRONIC METH-TREATED MICE, INCLUDING FIVE IEGS (ARC, EGR2, FOS, KLF10, AND NR4A1) AND ONE NEURONAL RECEPTOR GENE (GRM1), COMPARED WITH NORMAL SALINE-TREATED GROUP, BUT ONLY FOUR GENES (ARC, EGR2, FOS, AND NR4A1) WERE CONFIRMED TO BE DIFFERENT. FURTHERMORE, WE FOUND SEVERAL CPG SITES OF THE ARC AND THE FOS THAT HAD SIGNIFICANT CHANGES IN DNA METHYLATION STATUS IN THE FRONTAL CORTEX OF CHRONIC METH-TREATED MICE, WHILE THE KLF10 AND THE NR4A1 THAT HAD SIGNIFICANT CHANGES IN THE HIPPOCAMPUS. OUR RESULTS SHOW THAT CHRONIC ADMINISTRATION OF METH MAY LEAD TO SIGNIFICANT DOWNREGULATION OF THE IEGS EXPRESSION IN BOTH THE FRONTAL CORTEX AND THE HIPPOCAMPUS, WHICH MAY PARTLY ACCOUNT FOR THE MOLECULAR MECHANISM OF THE ACTION OF METH. FURTHERMORE, THE CHANGES IN DNA METHYLATION STATUS OF THE IEGS IN THE BRAIN INDICATE THAT AN EPIGENETIC MECHANISM-DEPENDENT TRANSCRIPTIONAL REGULATION MAY CONTRIBUTE TO METH ADDICTION, WHICH WARRANTS ADDITIONAL STUDY. 2015 10 886 46 CHRONIC CORTICOSTERONE EXPOSURE INCREASES EXPRESSION AND DECREASES DEOXYRIBONUCLEIC ACID METHYLATION OF FKBP5 IN MICE. THERE IS EVIDENCE FOR HYPERCORTISOLEMIA PLAYING A ROLE IN THE GENERATION OF PSYCHIATRIC SYMPTOMS AND FOR EPIGENETIC VARIATION WITHIN HYPOTHALAMIC-PITUITARY-ADRENAL (HPA) AXIS GENES MEDIATING BEHAVIORAL CHANGES. WE TESTED THE HYPOTHESIS THAT EXPRESSION CHANGES WOULD BE INDUCED IN FKBP5 AND OTHER HPA AXIS GENES BY CHRONIC EXPOSURE TO CORTICOSTERONE AND THAT THESE CHANGES WOULD OCCUR THROUGH THE EPIGENETIC MECHANISM OF LOSS OR GAIN OF DNA METHYLATION (DNAM). WE ADMINISTERED CORTICOSTERONE (CORT) TO C57BL/6J MICE VIA THEIR DRINKING WATER FOR 4 WK AND TESTED FOR BEHAVIORAL AND PHYSIOLOGICAL CHANGES AND CHANGES IN GENE EXPRESSION LEVELS USING RNA EXTRACTED FROM HIPPOCAMPUS, HYPOTHALAMUS, AND BLOOD FOR THE FOLLOWING HPA GENES: FKBP5, NR3C1, HSP90, CRH, AND CRHR1. THE CORT MICE EXHIBITED ANXIETY-LIKE BEHAVIOR IN THE ELEVATED PLUS MAZE TEST. CHRONIC EXPOSURE TO CORT ALSO CAUSED A SIGNIFICANT DECREASE IN THE HIPPOCAMPAL AND BLOOD MRNA LEVELS OF NR3C1 AND A DECREASE IN HSP90 IN BLOOD AND CAUSED AN INCREASE IN FKBP5 FOR ALL TISSUES. DIFFERENCES WERE SEEN IN FKBP5 METHYLATION IN HIPPOCAMPUS AND HYPOTHALAMUS. TO ISOLATE A SINGLE-CELL TYPE, WE FOLLOWED UP WITH AN HT-22 MOUSE HIPPOCAMPAL NEURONAL CELL LINE EXPOSED TO CORT. AFTER 7 D, WE OBSERVED A 2.4-FOLD INCREASE IN FKBP5 EXPRESSION AND A DECREASE IN DNAM. IN THE CORT-TREATED MICE, WE ALSO OBSERVED CHANGES IN BLOOD DNAM IN FKBP5. OUR RESULTS SUGGEST DNAM PLAYS A ROLE IN MEDIATING EFFECTS OF GLUCOCORTICOID EXPOSURE ON FKBP5 FUNCTION, WITH POTENTIAL CONSEQUENCES FOR BEHAVIOR. 2010 11 5443 43 REPEATED METHAMPHETAMINE AND MODAFINIL INDUCE DIFFERENTIAL COGNITIVE EFFECTS AND SPECIFIC HISTONE ACETYLATION AND DNA METHYLATION PROFILES IN THE MOUSE MEDIAL PREFRONTAL CORTEX. METHAMPHETAMINE (METH) AND MODAFINIL ARE PSYCHOSTIMULANTS WITH DIFFERENT LONG-TERM COGNITIVE PROFILES: METH IS ADDICTIVE AND LEADS TO COGNITIVE DECLINE, WHEREAS MODAFINIL HAS LITTLE ABUSE LIABILITY AND IS A COGNITIVE ENHANCER. INCREASING EVIDENCE IMPLICATES EPIGENETIC MECHANISMS OF GENE REGULATION BEHIND THE LASTING CHANGES THAT DRUGS OF ABUSE AND OTHER PSYCHOTROPIC COMPOUNDS INDUCE IN THE BRAIN, LIKE THE CONTROL OF GENE EXPRESSION BY HISTONES 3 AND 4 TAILS ACETYLATION (H3AC AND H4AC) AND DNA CYTOSINE METHYLATION (5-MC). MICE WERE TREATED WITH A SEVEN-DAY REPEATED METH, MODAFINIL OR VEHICLE PROTOCOL AND EVALUATED IN THE NOVEL OBJECT RECOGNITION (NOR) TEST OR SACRIFICED 4DAYS AFTER LAST INJECTION FOR MOLECULAR ASSAYS. WE EVALUATED TOTAL H3AC, H4AC AND 5-MC LEVELS IN THE MEDIAL PREFRONTAL CORTEX (MPFC), H3AC AND H4AC PROMOTOR ENRICHMENT (CHIP) AND MRNA EXPRESSION (RT-PCR) OF NEUROTRANSMITTER SYSTEMS INVOLVED IN AROUSAL, WAKEFULNESS AND COGNITIVE CONTROL, LIKE DOPAMINERGIC (DRD1 AND DRD2), ALPHA-ADRENERGIC (ADRA1A AND ADRA1B), OREXINERGIC (HCRTR1 AND HCRTR2), HISTAMINERGIC (HRH1 AND HRH3) AND GLUTAMATERGIC (AMPA GRIA1 AND NMDA GRIN1) RECEPTORS. REPEATED METH AND MODAFINIL TREATMENT ELICITED DIFFERENT COGNITIVE OUTCOMES IN THE NOR TEST, WHERE MODAFINIL-TREATED MICE PERFORMED AS CONTROLS AND METH-TREATED MICE SHOWED IMPAIRED RECOGNITION MEMORY. METH-TREATED MICE ALSO SHOWED I) DECREASED LEVELS OF TOTAL H3AC AND H4AC, AND INCREASED LEVELS OF 5-MC, II) DECREASED H3AC ENRICHMENT AT PROMOTERS OF DRD2, HCRTR1/2, HRH1 AND GRIN1, AND INCREASED H4AC ENRICHMENT AT DRD1, HRH1 AND GRIN1, III) INCREASED MRNA OF DRD1A, GRIN1 AND GRIA1. MODAFINIL-TREATED MICE SHARED NONE OF THESE EFFECTS AND SHOWED INCREASED H3AC ENRICHMENT AND MRNA EXPRESSION AT ADRA1B. MODAFINIL AND METH SHOWED SIMILAR EFFECTS LINKED TO DECREASED H3AC IN HRH3, INCREASED H4AC IN HCRTR1, AND DECREASED MRNA EXPRESSION OF HCRTR2. THE SPECIFIC METH-INDUCED EPIGENETIC AND TRANSCRIPTIONAL CHANGES DESCRIBED HERE MAY BE RELATED TO THE LONG-TERM COGNITIVE DECLINE EFFECTS OF THE DRUG AND ITS DETRIMENTAL EFFECTS ON MPFC FUNCTION. THE LACK OF SIMILAR EPIGENETIC EFFECTS OF CHRONIC MODAFINIL ADMINISTRATION SUPPORTS THIS NOTION. 2018 12 2630 43 EPIGENOME-WIDE ASSOCIATION STUDY OF POSTTRAUMATIC STRESS DISORDER IDENTIFIES NOVEL LOCI IN U.S. MILITARY VETERANS. POSTTRAUMATIC STRESS DISORDER (PTSD) IS A CHRONIC AND DISABLING PSYCHIATRIC DISORDER PREVALENT IN MILITARY VETERANS. EPIGENETIC MECHANISMS HAVE BEEN IMPLICATED IN THE ETIOLOGY OF PTSD, WITH DNA METHYLATION BEING THE MOST STUDIED TO IDENTIFY NOVEL MOLECULAR BIOMARKERS ASSOCIATED WITH THIS DISORDER. WE PERFORMED ONE OF THE LARGEST SINGLE-SAMPLE EPIGENOME-WIDE ASSOCIATION STUDIES (EWAS) OF PTSD TO DATE. OUR SAMPLE INCLUDED 1135 MALE EUROPEAN-AMERICAN U.S. VETERANS WHO PARTICIPATED IN THE NATIONAL HEALTH AND RESILIENCE IN VETERANS STUDY (NHRVS). DNA WAS COLLECTED FROM SALIVA SAMPLES AND THE ILLUMINA HUMANMETHYLATION EPIC BEADCHIP WAS USED FOR THE METHYLATION ANALYSIS. PTSD WAS ASSESSED USING THE PTSD CHECKLIST. AN EWAS WAS CONDUCTED USING LINEAR REGRESSION ADJUSTED FOR AGE, CELL-TYPE PROPORTIONS, FIRST 10 PRINCIPAL COMPONENTS, AND SMOKING STATUS. AFTER BONFERRONI CORRECTION, WE IDENTIFIED SIX GENOME-WIDE SIGNIFICANT (GWS) CPG SITES ASSOCIATED WITH PAST-MONTH PTSD AND THREE CPGS WITH LIFETIME PTSD (P(RANGE) = 10(-10)-10(-8)). THESE CPG SITES MAP TO GENES INVOLVED IN IMMUNE FUNCTION, TRANSCRIPTION REGULATION, AXONAL GUIDANCE, CELL SIGNALING, AND PROTEIN BINDING. AMONG THESE, SENP7, WHICH IS INVOLVED IN TRANSCRIPTION REGULATION AND HAS BEEN LINKED TO RISK-TAKING BEHAVIOR AND ALCOHOL CONSUMPTION IN GENOME-WIDE ASSOCIATION STUDIES, REPLICATED IN AN INDEPENDENT VETERAN COHORT AND WAS DOWNREGULATED IN MEDIAL ORBITOFRONTAL CORTEX OF PTSD POSTMORTEM BRAIN TISSUE. THESE FINDINGS SUGGEST POTENTIAL EPIGENETIC BIOMARKERS OF PTSD THAT MAY HELP INFORM THE PATHOPHYSIOLOGY OF THIS DISORDER IN VETERANS AND OTHER TRAUMA-AFFECTED POPULATIONS. 2022 13 1818 37 EFFECTS OF CHRONIC METHAMPHETAMINE EXPOSURE ON REWARDING BEHAVIOR AND NEURODEGENERATION MARKERS IN ADULT MICE. RECREATIONAL AND MEDICAL USE OF STIMULANTS AMONG YOUNG ADULTS HAVE GAINED POPULARITY IN THE UNITED STATES OVER THE LAST DECADE AND THEIR USE MAY INCREASE VULNERABILITY TO BRAIN BIOCHEMICAL CHANGES AND ADDICTIVE BEHAVIORS. THE LONG-TERM EFFECTS OF CHRONIC STIMULANT EXPOSURE IN LATER ADULTHOOD HAVE NOT BEEN FULLY ELUCIDATED.OUR STUDY INVESTIGATED WHETHER CHRONIC EXPOSURE TO METHAMPHETAMINE (METH), AT A DOSE DESIGNED TO EMULATE HUMAN THERAPEUTIC DOSING FOR ADHD, WOULD PROMOTE BIOCHEMICAL ALTERATIONS AND AFFECT SENSITIVITY TO THE REWARDING EFFECTS OF SUBSEQUENT METH DOSING.GROUPS OF 3.5-MONTH-OLD MALE AND FEMALE C57BL/6J MICE WERE ADMINISTERED NON-CONTINGENT INTRAPERITONEAL INJECTIONS OF EITHER SALINE OR METH (1.4 MG/KG) TWICE A DAY FOR 1 MONTH (5 DAYS/WEEK). METH (0.5 MG/KG)-INDUCED CONDITIONED PLACE PREFERENCE (CPP) WAS TESTED IN MICE TO DETERMINE THE EFFECTS OF PREVIOUS METH EXPOSURE ON REWARD-RELATED BEHAVIOR. MICE WERE RANDOMLY ASSIGNED TO EXPERIMENT I (MALES AND FEMALES) OR EXPERIMENT II (FEMALES ONLY) IN WHICH CPP TESTING WAS RESPECTIVELY PERFORMED EITHER 0.5 OR 5 MONTHS AFTER THE END OF METH INJECTIONS, AT ~5 OR 10 MONTHS OLD RESPECTIVELY. THE MIDBRAIN AND STRIATUM, REGIONS INVOLVED IN REWARD CIRCUIT, WERE ASSESSED FOR MARKERS ASSOCIATED WITH NEUROTOXICITY, DOPAMINERGIC FUNCTION, NEUROINFLAMMATION AND EPIGENETIC CHANGES AFTER BEHAVIORAL TESTING.PREVIOUS EXPOSURE TO CHRONIC METH DID NOT HAVE SIGNIFICANT SHORT-TERM EFFECTS ON CPP RESPONSE BUT LED TO A DECREASED CPP RESPONSE IN 10-MONTH-OLD FEMALES. PREVIOUS EXPOSURE TO METH INDUCED SOME SHORT-TERM CHANGES TO BIOCHEMICAL MARKERS MEASURED IN A BRAIN REGION AND SEX-DEPENDENT MANNER, WHILE LONG-TERM CHANGES WERE ONLY OBSERVED WITH GFAP AND KDM5C.IN CONCLUSION, OUR DATA SUGGEST SEX- AND POST-EXPOSURE DURATION-DEPENDENT OUTCOMES AND WARRANT FURTHER EXPLORATION OF THE LONG-TERM NEUROBEHAVIORAL CONSEQUENCES OF PSYCHOSTIMULANT USE IN BOTH SEXES. 2023 14 325 41 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 15 1761 40 EARLY STRESS EVOKES AGE-DEPENDENT BIPHASIC CHANGES IN HIPPOCAMPAL NEUROGENESIS, BDNF EXPRESSION, AND COGNITION. BACKGROUND: ADULT-ONSET STRESSORS EXERT OPPOSING EFFECTS ON HIPPOCAMPAL NEUROGENESIS AND COGNITION, WITH ENHANCEMENT OBSERVED FOLLOWING MILD STRESS AND DYSFUNCTION FOLLOWING SEVERE CHRONIC STRESS. WHILE EARLY LIFE STRESS EVOKES PERSISTENT CHANGES IN ANXIETY, IT IS UNKNOWN WHETHER EARLY STRESS DIFFERENTIALLY REGULATES HIPPOCAMPAL NEUROGENESIS, TROPHIC FACTOR EXPRESSION, AND COGNITION ACROSS THE LIFE SPAN. METHODS: HIPPOCAMPAL-DEPENDENT COGNITIVE BEHAVIOR, NEUROGENESIS, AND EPIGENETIC REGULATION OF BRAIN-DERIVED NEUROTROPHIC FACTOR (BDNF) EXPRESSION WAS EXAMINED AT DISTINCT TIME POINTS ACROSS THE LIFE SPAN IN RATS SUBJECTED TO THE EARLY STRESS OF MATERNAL SEPARATION (ES) AND CONTROL GROUPS. WE ALSO EXAMINED THE INFLUENCE OF CHRONIC ANTIDEPRESSANT TREATMENT ON THE NEUROGENIC, NEUROTROPHIC, AND COGNITIVE CHANGES IN MIDDLE-AGED ES ANIMALS. RESULTS: ANIMALS SUBJECTED TO EARLY STRESS OF MATERNAL SEPARATION EXAMINED DURING POSTNATAL LIFE AND YOUNG ADULTHOOD EXHIBITED ENHANCED HIPPOCAMPAL NEUROGENESIS, DECREASED REPRESSIVE HISTONE METHYLATION AT THE BDNF IV PROMOTER ALONG WITH ENHANCED BDNF LEVELS, AND IMPROVED PERFORMANCE ON THE STRESS-ASSOCIATED MORRIS WATER MAZE. STRIKINGLY, OPPOSING CHANGES IN HIPPOCAMPAL NEUROGENESIS AND EPIGENETIC REGULATION OF BDNF IV EXPRESSION, CONCOMITANT WITH IMPAIRMENTS ON HIPPOCAMPAL-DEPENDENT COGNITIVE TASKS, WERE OBSERVED IN MIDDLE-AGED ES ANIMALS. CHRONIC ANTIDEPRESSANT TREATMENT WITH AMITRIPTYLINE ATTENUATED THE MALADAPTIVE NEUROGENIC, EPIGENETIC, TRANSCRIPTIONAL, AND COGNITIVE EFFECTS IN MIDDLE-AGED ES ANIMALS. CONCLUSIONS: OUR STUDY PROVIDES NOVEL INSIGHTS INTO THE SHORT- AND LONG-TERM CONSEQUENCES OF ES, DEMONSTRATING BOTH BIPHASIC AND UNIQUE, AGE-DEPENDENT CHANGES AT THE MOLECULAR, EPIGENETIC, NEUROGENIC, AND BEHAVIORAL LEVELS. THESE RESULTS INDICATE THAT EARLY STRESS MAY TRANSIENTLY ENDOW ANIMALS WITH A POTENTIAL ADAPTIVE ADVANTAGE IN STRESSFUL ENVIRONMENTS BUT ACROSS A LIFE SPAN IS ASSOCIATED WITH LONG-TERM DELETERIOUS EFFECTS. 2013 16 3177 35 H3K9ME2 REGULATION OF BDNF EXPRESSION IN THE HIPPOCAMPUS AND MEDIAL PREFRONTAL CORTEX IS INVOLVED IN THE DEPRESSIVE-LIKE PHENOTYPE INDUCED BY MATERNAL SEPARATION IN MALE RATS. BACKGROUND: EARLY LIFE STRESS (ELS) INDUCES A DEPRESSIVE-LIKE PHENOTYPE AND INCREASES THE RISK OF DEPRESSION. BRAIN-DERIVED NEUROTROPHIC FACTOR (BDNF) HAS BEEN CONFIRMED TO BE INVOLVED IN THE PATHOPHYSIOLOGY OF DEPRESSION. HOWEVER, THE MECHANISM BY WHICH ELS ALTERS THE EPIGENETIC REGULATION OF BDNF AND CHANGES SUSCEPTIBILITY TO DEPRESSION HAS NOT BEEN FULLY CLARIFIED. METHODS: THE PRESENT STUDY USED MATERNAL SEPARATION (MS) AND CHRONIC UNPREDICTED MILD STRESS (CUMS) TO ESTABLISH AN MS ANIMAL MODEL AND A DEPRESSIVE ANIMAL MODEL. WE ASSESSED DEPRESSIVE-LIKE BEHAVIOURS, INCLUDING ANHEDONIA, LOCOMOTOR ACTIVITY, ANXIETY-LIKE BEHAVIOUR, AND SPATIAL MEMORY, USING THE SUCROSE PREFERENCE TEST, THE OPEN FIELD TEST, THE ELEVATED PLUS MAZE TEST, AND THE MORRIS WATER MAZE TEST. WE ALSO INVESTIGATED BDNF AND H3K9ME2 EXPRESSION IN THE HIPPOCAMPUS AND MEDIAL PREFRONTAL CORTEX (MPFC) BY IMMUNOHISTOCHEMISTRY, WESTERN BLOTTING, AND QPCR ANALYSIS. ADDITIONALLY, WE USED UNC0642, A SMALL MOLECULE INHIBITOR OF HISTONE METHYLTRANSFERASE (G9A), AS AN INTERVENTION. RESULTS: THE RESULTS SHOWED THAT CUMS INDUCED DEPRESSIVE-LIKE BEHAVIOURS IN RATS AND RESULTED IN INCREASED H3K9ME2 EXPRESSION AND DECREASED BDNF EXPRESSION IN THE HIPPOCAMPUS AND MPFC. MORE IMPORTANTLY, ADULT MS RATS EXPERIENCING CUMS HAD MORE SEVERE DEPRESSIVE BEHAVIOURS, HAD HIGHER EXPRESSION OF H3K9ME2 IN THE HIPPOCAMPUS AND MPFC, AND HAD LOWER EXPRESSION OF BDNF IN THE HIPPOCAMPUS AND MPFC. IN ADDITION, ADMINISTRATION OF THE G9A INHIBITOR REVERSED MOST OF THE CHANGES. CONCLUSIONS: OUR STUDY SUGGESTS THAT ELS CHANGED BDNF AND H3K9ME2 EXPRESSION IN THE RAT BRAIN, RESULTING IN A DEPRESSIVE-LIKE PHENOTYPE. 2021 17 521 39 ASSOCIATIONS BETWEEN MATERNAL PSYCHOSOCIAL STRESS, DNA METHYLATION, AND NEWBORN BIRTH WEIGHT IDENTIFIED BY INVESTIGATING METHYLATION AT INDIVIDUAL, REGIONAL, AND GENOME LEVELS. STRESS IS KNOWN TO AFFECT HEALTH THROUGHOUT LIFE AND INTO FUTURE GENERATIONS, BUT THE UNDERLYING MOLECULAR MECHANISMS ARE UNKNOWN. WE TESTED THE HYPOTHESIS THAT MATERNAL PSYCHOSOCIAL STRESS INFLUENCES DNA METHYLATION (DNAM), WHICH IN TURN IMPACTS NEWBORN HEALTH OUTCOMES. SPECIFICALLY, WE ANALYZED DNAM AT INDIVIDUAL, REGIONAL, AND GENOME-WIDE LEVELS TO TEST FOR ASSOCIATIONS WITH MATERNAL STRESS AND NEWBORN BIRTH WEIGHT. MATERNAL VENOUS BLOOD AND NEWBORN CORD BLOOD (N = 24 AND 22, RESPECTIVELY) WERE ASSAYED FOR METHYLATION AT APPROXIMATELY 450,000 CPG SITES. METHYLATION WAS ANALYZED BY EXAMINING CPG SITES INDIVIDUALLY IN AN EPIGENOME-WIDE ASSOCIATION STUDY (EWAS), AS REGIONAL GROUPS USING VARIABLY METHYLATED REGION (VMR) ANALYSIS IN MATERNAL BLOOD ONLY, AND THROUGH THE EPIGENOME-WIDE MEASURES USING GENOME-WIDE MEAN METHYLATION (GMM), HORVATH'S EPIGENETIC CLOCK, AND MITOTIC AGE. THESE METHYLATION MEASURES WERE TESTED FOR ASSOCIATION WITH THREE MEASURES OF MATERNAL STRESS (MATERNAL WAR TRAUMA, CHRONIC STRESS, AND EXPERIENCE OF SEXUAL VIOLENCE) AND ONE HEALTH OUTCOME (NEWBORN BIRTH WEIGHT). WE OBSERVED THAT MATERNAL EXPERIENCES OF WAR TRAUMA, CHRONIC STRESS, AND SEXUAL ASSAULT WERE EACH ASSOCIATED WITH DECREASED NEWBORN BIRTH WEIGHT (P < 1.95 X 10(-7) IN ALL CASES). TESTING INDIVIDUAL CPG SITES USING EWAS, WE OBSERVED NO ASSOCIATIONS BETWEEN DNAM AND ANY MEASURE OF MATERNAL STRESS OR NEWBORN BIRTH WEIGHT IN EITHER MATERNAL OR CORD BLOOD, AFTER BONFERRONI MULTIPLE TESTING CORRECTION. HOWEVER, THE TOP-RANKED CPG SITE IN MATERNAL BLOOD THAT ASSOCIATED WITH MATERNAL CHRONIC STRESS AND SEXUAL VIOLENCE BEFORE MULTIPLE TESTING CORRECTION IS LOCATED NEAR THE SPON1 GENE. TESTING AT A REGIONAL LEVEL, WE FOUND INCREASED METHYLATION OF A VMR IN MATERNAL BLOOD NEAR SPON1 THAT WAS ASSOCIATED WITH CHRONIC STRESS AND SEXUAL VIOLENCE AFTER BONFERRONI MULTIPLE TESTING CORRECTION (P = 1.95 X 10(-7) AND 8.3 X 10(-6), RESPECTIVELY). AT THE EPIGENOMIC LEVEL, CORD BLOOD GMM WAS ASSOCIATED WITH SIGNIFICANTLY HIGHER LEVELS OF WAR TRAUMA (P = 0.025) AND WAS SUGGESTIVELY ASSOCIATED WITH SEXUAL VIOLENCE (P = 0.053). THE OTHER TWO EPIGENOME-WIDE MEASURES WERE NOT ASSOCIATED WITH MATERNAL STRESS OR NEWBORN BIRTH WEIGHT IN EITHER TISSUE TYPE. DESPITE OUR SMALL SAMPLE SIZE, WE IDENTIFIED ASSOCIATIONS EVEN AFTER CONSERVATIVE MULTIPLE TESTING CORRECTION. SPECIFICALLY, WE FOUND ASSOCIATIONS BETWEEN DNAM AND THE THREE MEASURES OF MATERNAL STRESS ACROSS BOTH TISSUES; SPECIFICALLY, A VMR IN MATERNAL BLOOD AND GMM IN CORD BLOOD WERE BOTH ASSOCIATED WITH DIFFERENT MEASURES OF MATERNAL STRESS. THE ASSOCIATION OF CORD BLOOD GMM, BUT NOT MATERNAL BLOOD GMM, WITH MATERNAL STRESS MAY SUGGEST DIFFERENT RESPONSES TO STRESS IN MOTHER AND NEWBORN. IT IS NOTEWORTHY THAT WE FOUND ASSOCIATIONS ONLY WHEN CPG SITES WERE ANALYZED IN AGGREGATE, EITHER AS VMRS OR AS A BROAD SUMMARY MEASURE OF GMM. 2019 18 219 38 ACUTE IMMOBILIZATION STRESS FOLLOWING CONTEXTUAL FEAR CONDITIONING REDUCES FEAR MEMORY: TIMING IS ESSENTIAL. BACKGROUND: HISTONE ACETYLATION IS REGULATED IN RESPONSE TO STRESS AND PLAYS AN IMPORTANT ROLE IN LEARNING AND MEMORY. CHRONIC STRESS IS KNOWN TO DETERIORATE COGNITION, WHEREAS ACUTE STRESS FACILITATES MEMORY FORMATION. HOWEVER, WHETHER ACUTE STRESS FACILITATES MEMORY FORMATION WHEN IT IS APPLIED AFTER FEAR STIMULATION IS NOT YET KNOWN. THEREFORE, THIS STUDY AIMED TO INVESTIGATE THE EFFECT OF ACUTE STRESS APPLIED AFTER FEAR TRAINING ON MEMORY FORMATION, MRNA EXPRESSION OF BRAIN-DERIVED NEUROTROPHIC FACTOR (BDNF), EPIGENETIC REGULATION OF BDNF EXPRESSION, AND CORTICOSTERONE LEVEL IN MICE IN VIVO. METHODS: MICE WERE SUBJECTED TO ACUTE IMMOBILIZATION STRESS FOR 30 MIN AT 60 OR 90 MIN AFTER CONTEXTUAL FEAR CONDITIONING TRAINING, AND ACETYLATION OF HISTONE 3 AT LYSINE 14 (H3K14) AND LEVEL OF CORTICOSTERONE WERE MEASURED USING WESTERN BLOT ANALYSIS AND ENZYME-LINKED IMMUNOSORBENT ASSAY (ELISA), RESPECTIVELY. A FREEZING BEHAVIOR TEST WAS PERFORMED 24 H AFTER TRAINING, AND MRNA EXPRESSION OF BDNF WAS MEASURED USING REAL-TIME POLYMERASE CHAIN REACTIONS. DIFFERENT GROUPS OF MICE WERE USED FOR EACH TEST. RESULTS: FREEZING BEHAVIOR SIGNIFICANTLY DECREASED WITH THE DOWN-REGULATION OF BDNF MRNA EXPRESSION CAUSED BY ACUTE IMMOBILIZATION STRESS AT 60 MIN AFTER FEAR CONDITIONING TRAINING OWING TO THE REDUCTION OF H3K14 ACETYLATION. HOWEVER, BDNF MRNA EXPRESSION AND H3K14 ACETYLATION WERE NOT REDUCED IN ANIMALS SUBJECTED TO IMMOBILIZATION STRESS AT 90 MIN AFTER THE TRAINING. FURTHER, THE CORTICOSTERONE LEVEL WAS SIGNIFICANTLY HIGH IN MICE SUBJECTED TO IMMOBILIZATION STRESS AT 60 MIN AFTER THE TRAINING. CONCLUSION: ACUTE IMMOBILIZATION STRESS FOR 30 MIN AT 60 MIN AFTER FEAR CONDITIONING TRAINING IMPAIRED MEMORY FORMATION AND REDUCED BDNF MRNA EXPRESSION AND H3K14 ACETYLATION IN THE HIPPOCAMPUS OF MICE OWING TO THE HIGH LEVEL OF CORTICOSTERONE. 2016 19 5200 33 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 20 579 50 BEHAVIORAL AND MOLECULAR NEUROEPIGENETIC ALTERATIONS IN PRENATALLY STRESSED MICE: RELEVANCE FOR THE STUDY OF CHROMATIN REMODELING PROPERTIES OF ANTIPSYCHOTIC DRUGS. WE HAVE RECENTLY REPORTED THAT MICE BORN FROM DAMS STRESSED DURING PREGNANCY (PRS MICE), IN ADULTHOOD, HAVE BEHAVIORAL DEFICITS REMINISCENT OF BEHAVIORS OBSERVED IN SCHIZOPHRENIA (SZ) AND BIPOLAR (BP) DISORDER PATIENTS. FURTHERMORE, WE HAVE SHOWN THAT THE FRONTAL CORTEX (FC) AND HIPPOCAMPUS OF ADULT PRS MICE, LIKE THAT OF POSTMORTEM CHRONIC SZ PATIENTS, ARE CHARACTERIZED BY INCREASES IN DNA-METHYLTRANSFERASE 1 (DNMT1), TEN-ELEVEN METHYLCYTOSINE DIOXYGENASE 1 (TET1) AND EXHIBIT AN ENRICHMENT OF 5-METHYLCYTOSINE (5MC) AND 5-HYDROXYMETHYLCYTOSINE (5HMC) AT NEOCORTICAL GABAERGIC AND GLUTAMATERGIC GENE PROMOTERS. HERE, WE SHOW THAT THE BEHAVIORAL DEFICITS AND THE INCREASED 5MC AND 5HMC AT GLUTAMIC ACID DECARBOXYLASE 67 (GAD1), REELIN (RELN) AND BRAIN-DERIVED NEUROTROPHIC FACTOR (BDNF) PROMOTERS AND THE REDUCED EXPRESSION OF THE MESSENGER RNAS (MRNAS) AND PROTEINS CORRESPONDING TO THESE GENES IN FC OF ADULT PRS MICE IS REVERSED BY TREATMENT WITH CLOZAPINE (5 MG KG(-1) TWICE A DAY FOR 5 DAYS) BUT NOT BY HALOPERIDOL (1 MG KG(-1) TWICE A DAY FOR 5 DAYS). INTERESTINGLY, CLOZAPINE HAD NO EFFECT ON EITHER THE BEHAVIOR, PROMOTER METHYLATION OR THE EXPRESSION OF THESE MRNAS AND PROTEINS WHEN ADMINISTERED TO OFFSPRING OF NONSTRESSED PREGNANT MICE. CLOZAPINE, BUT NOT HALOPERIDOL, REDUCED THE ELEVATED LEVELS OF DNMT1 AND TET1, AS WELL AS THE ELEVATED LEVELS OF DNMT1 BINDING TO GAD1, RELN AND BDNF PROMOTERS IN PRS MICE SUGGESTING THAT CLOZAPINE, UNLIKE HALOPERIDOL, MAY LIMIT DNA METHYLATION BY INTERFERING WITH DNA METHYLATION DYNAMICS. WE CONCLUDE THAT THE PRS MOUSE MODEL MAY BE USEFUL PRECLINICALLY IN SCREENING FOR THE POTENTIAL EFFICACY OF ANTIPSYCHOTIC DRUGS ACTING ON ALTERED EPIGENETIC MECHANISMS. FURTHERMORE, PRS MICE MAY BE INVALUABLE FOR UNDERSTANDING THE ETIOPATHOGENESIS OF SZ AND BP DISORDER AND FOR PREDICTING TREATMENT RESPONSES AT EARLY STAGES OF THE ILLNESS ALLOWING FOR EARLY DETECTION AND REMEDIAL INTERVENTION. 2016