1 4857 156 OPTOGENETIC STIMULATION OF THE ANTERIOR CINGULATE CORTEX AMELIORATES AUTISTIC-LIKE BEHAVIORS IN RATS INDUCED BY NEONATAL ISOLATION, CAUDATE PUTAMEN AS A SITE FOR ALTERATION. EPIGENETIC AGENTS, SUCH AS NEONATAL ISOLATION DURING NEURODEVELOPMENTAL PERIOD OF LIFE, CAN CHANGE VARIOUS REGIONS OF THE BRAIN. IT MAY FURTHER INDUCE PSYCHOLOGICAL DISORDERS SUCH AS AUTISTIC-LIKE PHENOMENA. THIS STUDY INDICATED THE ROLE OF CHRONIC INCREASED ANTERIOR CINGULATE CORTEX (ACC) OUTPUT ON ALTERATION OF CAUDATE PUTAMEN (CPU) AS A MAIN BEHAVIOR REGULATOR REGION OF THE BRAIN IN ADULT MATERNAL DEPRIVED (MD) RATS. FOR MAKING AN ANIMAL MODEL, NEONATES WERE ISOLATED FROM THEIR MOTHERS IN POSTNATAL DAYS (PND 1-10, 3 H/DAY). SUBSEQUENTLY, THEY BILATERALLY RECEIVED PLENTI-CAMKIIA-HCHR2 (H134R)-MCHERRY-WPRE VIRUS IN ACC AREA VIA STEREOTAXIC SURGERY IN PND50. AFTER 22 DAYS, THESE REGIONS WERE EXPOSED TO BLUE LASER (473 NM) FOR SIX CONSECUTIVE DAYS (15 MIN/DAY). THEN, BEHAVIORAL DEFICITS WERE TESTED AND WERE COMPARED WITH CONTROL GROUP IN THE FOLLOWING DAY. ANIMALS WERE IMMEDIATELY KILLED AND THEIR BRAINS WERE PREPARED FOR TISSUE PROCESSING. RESULTS SHOWED THAT NEONATAL ISOLATION INDUCES AUTISTIC-LIKE BEHAVIORS AND LEADS TO OVEREXPRESSION OF NMDAR1 AND NOX2-GP91(PHOX) PROTEINS AND ELEVATION OF CATALASE ACTIVITY IN THE CPU REGIONS OF THE ADULT OFFSPRING COMPARED WITH CONTROL GROUP. CHRONIC OPTOGENETIC STIMULATION OF ACC NEURONS CONTAINING (CHR2+) LED TO SIGNIFICANT REDUCTION IN THE APPEARANCE OF STEREOTYPICAL BEHAVIOR AND ALIEN-PHOBIA IN MD RATS. THE AMOUNT OF NMDAR1 AND NOX2-GP91(PHOX) EXPRESSION AND THE CATALASE ACTIVITY IN CPU WERE REDUCED AFTER THIS TREATMENT. THEREFORE, AUTISTIC-LIKE BEHAVIOR SEEMS TO BE RELATED WITH ELEVATION OF NMDAR1 AND NOX2-GP91(PHOX) PROTEIN LEVELS THAT ENHANCE THE EFFECT OF GLUTAMATERGIC PROJECTION ON CPU REGIONS. OPTOGENETIC TREATMENT ALSO COULD AMELIORATE BEHAVIORAL DEFICITS BY MODULATING THESE PROTEIN DENSITIES. 2019 2 5205 40 PRENATAL STRESS CHANGES THE GLYCOPROTEIN GPM6A GENE EXPRESSION AND INDUCES EPIGENETIC CHANGES IN RAT OFFSPRING BRAIN. PRENATAL STRESS (PS) EXERTS STRONG IMPACT ON FETAL BRAIN DEVELOPMENT AND ON ADULT OFFSPRING BRAIN FUNCTIONS. PREVIOUS WORK DEMONSTRATED THAT CHRONIC STRESS ALTERS THE MRNA EXPRESSION OF GPM6A, A NEURONAL GLYCOPROTEIN INVOLVED IN FILOPODIUM EXTENSION. IN THIS WORK, WE ANALYZED THE EFFECT OF PS ON GPM6A EXPRESSION AND THE EPIGENETIC MECHANISMS INVOLVED. PREGNANT WISTAR RATS RECEIVED RESTRAINT STRESS DURING THE LAST WEEK OF GESTATION. MALE OFFSPRING WERE SACRIFICED ON POSTNATAL DAYS 28 AND 60. HIPPOCAMPUS AND PREFRONTAL CORTEX SAMPLES WERE ANALYZED FOR GENE EXPRESSION (QPCR FOR MRNAS AND MICRORNAS), METHYLATION STATUS (BISULFITE CONVERSION) AND PROTEIN LEVELS. HIPPOCAMPAL NEURONS IN CULTURE WERE USED TO ANALYZE MICRORNA OVEREXPRESSION EFFECTS. PRENATAL STRESS INDUCED CHANGES IN GPM6A LEVELS IN BOTH TISSUES AND AT BOTH AGES ANALYZED, INDICATING A PERSISTENT EFFECT. TWO CPG ISLANDS IN THE GPM6A GENE WERE IDENTIFIED. VARIATIONS IN THE METHYLATION PATTERN AT THREE SPECIFIC CPGS WERE FOUND IN HIPPOCAMPUS, BUT NOT IN PFC SAMPLES FROM PS OFFSPRING. MICRORNAS PREDICTED TO TARGET GPM6A WERE IDENTIFIED IN SILICO. QPCR MEASUREMENTS SHOWED THAT PS MODIFIED THE EXPRESSION OF SEVERAL MICRORNAS IN BOTH TISSUES, BEING MICRORNA-133B THE MOST SIGNIFICANTLY ALTERED. FURTHER STUDIES OVEREXPRESSING THIS MICRORNA IN NEURONAL CULTURES SHOWED A REDUCTION IN GMP6A MRNA AND PROTEIN LEVEL. MOREOVER FILOPODIUM DENSITY WAS ALSO REDUCED, SUGGESTING THAT GPM6A FUNCTION WAS AFFECTED. GESTATIONAL STRESS AFFECTED GPM6A GENE EXPRESSION IN OFFSPRING LIKELY THROUGH CHANGES IN METHYLATION STATUS AND IN POSTTRANSCRIPTIONAL REGULATION BY MICRORNAS. THUS, OUR FINDINGS PROPOSE GPM6A AS A NOVEL TARGET FOR EPIGENETIC REGULATION DURING PRENATAL STRESS. 2014 3 3325 38 HISTONE DEACETYLASE 2-MEDIATED EPIGENETIC REGULATION IS INVOLVED IN THE EARLY ISOFLURANE EXPOSURE-RELATED INCREASE IN SUSCEPTIBILITY TO ANXIETY-LIKE BEHAVIOUR EVOKED BY CHRONIC VARIABLE STRESS IN MICE. INCREASING STUDIES REPORT THAT PROLONGED OR MULTIPLE ANAESTHETIC EXPOSURES EARLY IN LIFE ARE ASSOCIATED WITH DETRIMENTAL EFFECTS ON BRAIN FUNCTION. ALTHOUGH STUDIES HAVE EVALUATED THE DETRIMENTAL EFFECTS ON NEUROCOGNITIVE FUNCTION, FEW HAVE FOCUSED ON LONG-TERM NEUROPSYCHIATRIC EFFECTS. IN THE PRESENT STUDY, C57BL/6 MICE RECEIVED EITHER THREE NEONATAL ISOFLURANE EXPOSURES OR CONTROL EXPOSURE. STARTING ON POSTNATAL DAY 45, THE MICE WERE EITHER EXPOSED OR NOT TO A CHRONIC VARIABLE STRESS (CVS) PARADIGM, AND CVS-RELATED NEUROPSYCHIATRIC PERFORMANCE WAS EVALUATED USING A SERIES OF BEHAVIOURAL TESTS. THE EXPRESSION LEVELS OF HISTONE 3 LYSINE 9 ACETYLATION (ACETYL-H3K9), BRAIN-DERIVED NEUROTROPHIC FACTOR (BDNF), CAMP RESPONSE ELEMENT-BINDING PROTEIN-BINDING PROTEIN, AND HISTONE DEACETYLASES 1-4 IN THE AMYGDALA WERE MEASURED BY IMMUNOBLOTTING OR IMMUNOHISTOCHEMISTRY ANALYSIS. IN MICE WITH NEONATAL ISOFLURANE EXPOSURE, THE EFFECTS OF SODIUM BUTYRATE (NAB), A COMMONLY USED HDAC INHIBITOR, WERE EXAMINED ON CVS-RELATED BEHAVIOURAL AND MOLECULAR ALTERATIONS. THE RESULTS SHOWED THAT REPEATED NEONATAL ISOFLURANE EXPOSURE DID NOT AFFECT INNATE DEPRESSION-LIKE AND ANXIETY-LIKE BEHAVIOURS UNDER NON-STRESS CONDITIONS BUT FACILITATED THE CVS-INDUCED ANXIETY-LIKE BEHAVIOURAL PHENOTYPE. INCREASED HDAC2 EXPRESSION IN THE AMYGDALA WAS ASSOCIATED WITH AN INCREASE IN THE CVS-INDUCED REPRESSION OF ACETYL-H3K9 AND BDNF EXPRESSION AND AN ENHANCED CVS-EVOKED ANXIETY-LIKE BEHAVIOURAL PHENOTYPE IN MICE NEONATAL ISOFLURANE EXPOSURE. NAB SIGNIFICANTLY DECREASED THE CVS-INDUCED ANXIETY LEVEL BY ELEVATING ACETYL-H3K9 AND BDNF EXPRESSION. THESE RESULTS SUGGESTED THAT EARLY ANAESTHESIA EXPOSURE FACILITATED CHRONIC STRESS-INDUCED NEUROPSYCHIATRIC OUTCOMES, AND THE HDAC2-RELATED EPIGENETIC DYSREGULATION OF BDNF GENE EXPRESSION IS INVOLVED IN THE UNDERLYING MECHANISM. 2021 4 905 33 CHRONIC EXPOSURE TO CANNABINOIDS DURING ADOLESCENCE CAUSES LONG-LASTING BEHAVIORAL DEFICITS IN ADULT MICE. REGULAR USE OF MARIJUANA DURING ADOLESCENCE ENHANCES THE RISK OF LONG-LASTING NEUROBIOLOGICAL CHANGES IN ADULTHOOD. THE PRESENT STUDY WAS AIMED AT ASSESSING THE EFFECT OF LONG-TERM ADMINISTRATION OF THE SYNTHETIC CANNABINOID WIN55212.2 DURING ADOLESCENCE IN YOUNG ADULT MICE. ADOLESCENT MICE AGED 5 WEEKS WERE SUBJECTED DAILY TO THE PHARMACOLOGICAL ACTION OF WIN55212.2 FOR 3 WEEKS AND WERE THEN LEFT UNDISTURBED IN THEIR HOME CAGE FOR A 5-WEEK PERIOD AND FINALLY EVALUATED BY BEHAVIORAL TESTING. MICE THAT RECEIVED THE DRUG DURING ADOLESCENCE SHOWED MEMORY IMPAIRMENT IN THE MORRIS WATER MAZE, AS WELL AS A DOSE-DEPENDENT MEMORY IMPAIRMENT IN FEAR CONDITIONING. IN ADDITION, THE ADMINISTRATION OF 3 MG/KG WIN55212.2 IN ADOLESCENCE INCREASED ADULT HIPPOCAMPAL AEA LEVELS AND PROMOTED DNA HYPERMETHYLATION AT THE INTRAGENIC REGION OF THE INTRACELLULAR SIGNALING MODULATOR RGS7, WHICH WAS ACCOMPANIED BY A LOWER RATE OF MRNA TRANSCRIPTION OF THIS GENE, SUGGESTING A POTENTIAL CAUSAL RELATION. ALTHOUGH THE CONCRETE MECHANISMS UNDERLYING THE BEHAVIORAL OBSERVATIONS REMAIN TO BE ELUCIDATED, WE DEMONSTRATE THAT LONG-TERM ADMINISTRATION OF 3 MG/KG OF WIN DURING ADOLESCENCE LEADS TO INCREASED ENDOCANNABINOID LEVELS AND ALTERED RGS7 EXPRESSION IN ADULTHOOD AND ESTABLISH A POTENTIAL LINK TO EPIGENETIC CHANGES. 2017 5 5339 35 QUETIAPINE TREATMENT REVERSES DEPRESSIVE-LIKE BEHAVIOR AND REDUCES DNA METHYLTRANSFERASE ACTIVITY INDUCED BY MATERNAL DEPRIVATION. STRESS IN EARLY LIFE HAS BEEN APPOINTED AS AN IMPORTANT PHENOMENON IN THE ONSET OF DEPRESSION AND POOR RESPONSE TO TREATMENT WITH CLASSICAL ANTIDEPRESSANTS. FURTHERMORE, CHILDHOOD TRAUMA TRIGGERS EPIGENETIC CHANGES, WHICH ARE ASSOCIATED WITH THE PATHOPHYSIOLOGY OF MAJOR DEPRESSIVE DISORDER (MDD). TREATMENT WITH ATYPICAL ANTIPSYCHOTICS SUCH AS QUETIAPINE, EXERTS THERAPEUTIC EFFECT FOR MDD PATIENTS AND INDUCES EPIGENETIC CHANGES. THIS STUDY AIMED TO ANALYZE THE EFFECT OF CHRONIC TREATMENT WITH QUETIAPINE (20MG/KG) ON DEPRESSIVE-LIKE BEHAVIOR OF RATS SUBMITTED TO MATERNAL DEPRIVATION (MD), AS WELL AS THE ACTIVITY OF HISTONE ACETYLATION BY THE ENZYMES HISTONE ACETYL TRANSFERASES (HAT) AND DEACETYLASES (HDAC) AND DNA METHYLATION, THROUGH DNA METHYLTRANSFERASE ENZYME (DNMT) IN THE PREFRONTAL CORTEX (PFC), NUCLEUS ACCUMBENS (NAC) AND HIPPOCAMPUS. MATERNALLY DEPRIVED RATS HAD A DEPRESSIVE-LIKE BEHAVIOR IN THE FORCED SWIMMING TEST AND AN INCREASE IN THE HDAC AND DNMT ACTIVITIES IN THE HIPPOCAMPUS AND NAC. TREATMENT WITH QUETIAPINE REVERSED DEPRESSIVE-LIKE BEHAVIOR AND REDUCED THE DNMT ACTIVITY IN THE HIPPOCAMPUS. THIS IS THE FIRST STUDY TO SHOW THE ANTIDEPRESSANT-LIKE EFFECT OF QUETIAPINE IN ANIMALS SUBJECTED TO MD AND A PROTECTIVE EFFECT BY QUETIAPINE IN REDUCING EPIGENETIC CHANGES INDUCED BY STRESS IN EARLY LIFE. THESE RESULTS REINFORCE AN IMPORTANT ROLE OF QUETIAPINE AS THERAPY FOR MDD. 2017 6 5152 33 PPM1F IN DENTATE GYRUS MODULATES ANXIETY-RELATED BEHAVIORS BY REGULATING BDNF EXPRESSION VIA AKT/JNK/P-H3S10 PATHWAY. ANXIETY IS A SERIOUS PSYCHIATRIC DISORDER, WITH A HIGHER INCIDENCE RATE IN WOMEN THAN IN MEN. PROTEIN PHOSPHATASE MG(2+)/MN(2+)-DEPENDENT 1F (PPM1F), A SERINE/THREONINE PHOSPHATASE, HAS BEEN SHOWN TO HAVE MULTIPLE BIOLOGICAL AND CELLULAR FUNCTIONS. HOWEVER, THE EFFECTS OF PPM1F AND ITS NEURONAL SUBSTRATES ON ANXIETY REMAIN LARGELY UNCLEAR. IN THIS STUDY, WE SHOWED THAT CHRONIC RESTRAINT STRESS (CRS) INDUCED ANXIETY-RELATED BEHAVIORS ONLY IN FEMALE MICE, WHILE ACUTE RESTRAINT STRESS (ARS) PRODUCED ANXIETY-RELATED BEHAVIORS IN BOTH MALE AND FEMALE MICE IN LIGHT-DARK AND ELEVATED PLUS MAZE TESTS AND INDUCED UPREGULATION OF PPM1F AND DOWNREGULATION OF BRAIN-DERIVED NEUROTROPHIC FACTOR (BDNF) EXPRESSION IN THE HIPPOCAMPUS. ADENO-ASSOCIATED VIRUS-MEDIATED OVEREXPRESSION OF PPM1F OR CONDITIONAL KNOCKOUT OF BDNF IN DENTATE GYRUS (DG) LED TO A MORE PRONOUNCED ANXIETY-RELATED BEHAVIOR IN FEMALE THAN IN MALE MICE AS INDICATED BY THE BEHAVIORAL EVALUATIONS. MEANWHILE, OVEREXPRESSION OF PPM1F IN THE DG DECREASED TOTAL BDNF EXON-SPECIFIC MESSENGER RNA EXPRESSION IN THE HIPPOCAMPUS WITH THE DECREASED BINDING ACTIVITY OF PHOSPHORYLATED H3S10 TO ITS INDIVIDUAL PROMOTERS IN FEMALE MICE. FURTHERMORE, WE IDENTIFIED THAT OVEREXPRESSION OF PPM1F DECREASED THE PHOSPHORYLATION LEVELS OF AKT AND JNK IN THE HIPPOCAMPUS OF FEMALE MICE. THESE RESULTS MAY SUGGEST THAT PPM1F REGULATES ANXIETY-RELATED BEHAVIORS BY MODULATING BDNF EXPRESSION AND H3S10 PHOSPHORYLATION-MEDIATED EPIGENETIC MODIFICATION, WHICH MAY BE SERVED AS POTENTIALLY PATHOLOGICAL GENES ASSOCIATED WITH ANXIETY OR OTHER MENTAL DISEASES. 2021 7 433 28 ANTIDEPRESSANT TREATMENT IS ASSOCIATED WITH EPIGENETIC ALTERATIONS OF HOMER1 PROMOTER IN A MOUSE MODEL OF CHRONIC DEPRESSION. BACKGROUND: UNDERSTANDING THE NEUROBIOLOGY OF DEPRESSION AND THE MECHANISM OF ACTION OF THERAPEUTIC MEASURES IS CURRENTLY A RESEARCH PRIORITY. WE HAVE SHOWN THAT THE EXPRESSION OF THE SYNAPTIC PROTEIN HOMER1A CORRELATES WITH DEPRESSION-LIKE BEHAVIOR AND ITS INDUCTION IS A COMMON MECHANISM OF ACTION OF DIFFERENT ANTIDEPRESSANT TREATMENTS. HOWEVER, THE MECHANISM OF HOMER1A REGULATION IS STILL UNKNOWN. METHODS: WE COMBINED THE CHRONIC DESPAIR MOUSE MODEL (CDM) OF CHRONIC DEPRESSION WITH DIFFERENT ANTIDEPRESSANT TREATMENTS. DEPRESSION-LIKE BEHAVIOR WAS CHARACTERIZED BY FORCED SWIM AND TAIL SUSPENSION TESTS, AND VIA AUTOMATIC MEASUREMENT OF SUCROSE PREFERENCE IN INTELLICAGE. THE HOMER1 MRNA EXPRESSION AND PROMOTER DNA METHYLATION WERE ANALYZED IN CORTEX AND PERIPHERAL BLOOD BY QRT-PCR AND PYROSEQUENCING. RESULTS: CDM MICE SHOW DECREASED HOMER1A AND HOMER1B/C MRNA EXPRESSION IN CORTEX AND BLOOD SAMPLES, WHILE CHRONIC TREATMENT WITH IMIPRAMINE AND FLUOXETINE OR ACUTE KETAMINE APPLICATION INCREASES THEIR LEVEL ONLY IN THE CORTEX. THE QUANTITATIVE ANALYSES OF THE METHYLATION OF 7 CPG SITES, LOCATED ON THE HOMER1 PROMOTER REGION CONTAINING SEVERAL CRE BINDING SITES, SHOW A SIGNIFICANT INCREASE IN DNA METHYLATION IN THE CORTEX OF CDM MICE. IN CONTRAST, ANTIDEPRESSANT TREATMENTS REDUCE THE METHYLATION LEVEL. LIMITATIONS: HOMER1 EXPRESSION AND PROMOTOR METHYLATION WERE NOT ANALYZED IN DIFFERENT BLOOD CELL TYPES. OTHER CPG SITES OF HOMER1 PROMOTER SHOULD BE INVESTIGATED IN FUTURE STUDIES. OUR EXPERIMENTAL APPROACH DOES NOT DISTINGUISH BETWEEN METHYLATION AND HYDROXYMETHYLATION. CONCLUSIONS: WE DEMONSTRATE THAT STRESS-INDUCED DEPRESSION-LIKE BEHAVIOR AND ANTIDEPRESSANT TREATMENTS ARE ASSOCIATED WITH EPIGENETIC ALTERATIONS OF HOMER1 PROMOTER, PROVIDING NEW INSIGHTS INTO THE MECHANISM OF ANTIDEPRESSANT TREATMENT. 2021 8 889 35 CHRONIC DIETARY ADMINISTRATION OF VALPROIC ACID PROTECTS NEURONS OF THE RAT NUCLEUS BASALIS MAGNOCELLULARIS FROM IBOTENIC ACID NEUROTOXICITY. VALPROIC ACID (VPA) HAS BEEN USED FOR MANY YEARS AS A DRUG OF CHOICE FOR EPILEPSY AND MOOD DISORDERS. RECENTLY, EVIDENCE HAS BEEN PROPOSED FOR A WIDE SPECTRUM OF ACTIONS OF THIS DRUG, INCLUDING ANTITUMORAL AND NEUROPROTECTIVE PROPERTIES. VALPROIC ACID-MEDIATED NEUROPROTECTION IN VIVO HAS BEEN SO FAR DEMONSTRATED IN A LIMITED NUMBER OF EXPERIMENTAL MODELS. IN THIS STUDY, WE HAVE TESTED THE NEUROPROTECTIVE POTENTIAL OF CHRONIC (4 + 1 WEEKS) DIETARY ADMINISTRATION OF VPA ON DEGENERATION OF CHOLINERGIC AND GABAERGIC NEURONS OF THE RAT NUCLEUS BASALIS MAGNOCELLULARIS (NBM), INJECTED WITH THE EXCITOTOXIN, IBOTENIC ACID (IBO), AN ANIMAL MODELS THAT IS RELEVANT FOR ALZHEIMER'S DISEASE-LIKE NEURODEGENERATION. WE SHOW THAT VPA TREATMENT SIGNIFICANTLY PROTECTS BOTH CHOLINERGIC AND GABAERGIC NEURONS PRESENT IN THE INJECTED AREA FROM THE EXCITOTOXIC INSULT. A SIGNIFICANT LEVEL OF NEUROPROTECTION, IN PARTICULAR, IS EXERTED TOWARDS THE CHOLINERGIC NEURONS OF THE NBM PROJECTING TO THE CORTEX, AS DEMONSTRATED BY THE SUBSTANTIALLY HIGHER LEVELS OF CHOLINERGIC MARKERS MAINTAINED IN THE TARGET CORTICAL AREA OF VPA-TREATED RATS AFTER IBO INJECTION IN THE NBM. WE FURTHER SHOW THAT CHRONIC VPA ADMINISTRATION RESULTS IN INCREASED ACETYLATION OF HISTONE H3 IN BRAIN, CONSISTENT WITH THE HISTONE DEACETYLASE INHIBITORY ACTION OF VPA AND PUTATIVELY LINKED TO A NEUROPROTECTIVE ACTION OF THE DRUG MEDIATED AT THE EPIGENETIC LEVEL. 2009 9 2886 27 GABA-AALPHA5 MIGHT BE INVOLVED IN LEARNING-MEMORY DYSFUNCTION IN THE OFFSPRINGS OF CHRONIC ETHANOL-TREATED RATS VIA GABA-AALPHA5 HISTONE H3K9 ACETYLATION. RECENTLY, NUMEROUS STUDIES HAVE BEEN FOCUSED ON THE RELATIONSHIP BETWEEN GABA-A RECEPTORS AND ALCOHOL-INDUCED SPATIAL LEARNING AND MEMORY DEFICITS. GABA-AALPHA5, A SUBUNIT OF GABA-A RECEPTORS, IS CONSIDERED TO PLAY AN IMPORTANT ROLE IN ALCOHOL-INDUCED COGNITIVE IMPAIRMENT, HOWEVER, THE MECHANISM REMAINS OBSCURE. IN THIS STUDY, WE FOUND THAT THE EXPRESSION OF GABA-AALPHA5 INCREASED IN RATS TREATED WITH CHRONIC ETHANOL VIA HISTONE H3K9 ACETYLATION. FURTHERMORE, THIS EPIGENETIC MODIFICATION COULD BE INHERITED BY THE NEXT GENERATIONS, WHICH EVENTUALLY EXHIBIT SIMILAR SPATIAL LEARNING AND MEMORY DEFICITS IN THE OFFSPRINGS. IN SUMMARY, OUR RESULTS SUGGESTED THAT GABA-AALPHA5 MIGHT BE INVOLVED IN CHRONIC ETHANOL TREATMENT-INDUCED LEARNING-MEMORY DYSFUNCTION AND FOR THE FIRST TIME PROVED THAT LEARNING-MEMORY DYSFUNCTION COULD BE INHERITED BY THE OFFSPRINGS VIA HISTONE H3K9 ACETYLATION. HOPEFULLY, IN THE NEAR FUTURE, GABA-AALPHA5 INHIBITORS WOULD BE AN EFFECTIVE WAY TO TREAT ALCOHOL-INDUCED COGNITION IMPAIRMENT. 2019 10 3986 36 LONG-TERM OVARIECTOMY INCREASES BDNF GENE METHYLATION STATUS IN MOUSE HIPPOCAMPUS. ESTRADIOL (E) HAS BEEN SUGGESTED TO HAVE A NEUROPROTECTIVE EFFECT IN YOUNG ANIMALS BUT HAS NEUTRAL OR HARMFUL EFFECTS WHEN IT IS ADMINISTERED TO AGED ANIMALS. IN THE PRESENT STUDY, WE DETERMINED WHETHER THE POST-OVARIECTOMY (POST-OVX) TIMEFRAME ELAPSED BEFORE THE INITIATION OF CHRONIC E TREATMENT IS CRITICAL FOR THE ESTROGENIC INDUCTION OF NEUROTROPHINS (BRAIN-DERIVED NEUROTROPHIC FACTOR, BDNF, AND SYNAPTOPHYSIN, SYN) IN THE RODENT HIPPOCAMPUS. ADULT MICE WERE OVX AND, A SHORT PERIOD (SHORT-TERM E (STE) ANIMALS) OR A LONG PERIOD (LONG-TERM E (LTE) ANIMALS) AFTER THE OVX, WERE DAILY TREATED WITH E. CONTROL ANIMALS WERE TREATED WITH SESAME OIL (SHORT-TERM CONTROL (STC) AND LONG-TERM CONTROL (LTC) ANIMALS). PROTEIN EXPRESSION WAS DETERMINED USING AN IMMUNOHISTOCHEMICAL APPROACH. TRANSCRIPTIONAL ACTIVITY IN THE HIPPOCAMPUS OF INDIVIDUAL BDNF PROMOTERS WAS ASSESSED BY REAL-TIME QUANTITATIVE RT-PCR, AND THE METHYLATION LEVELS OF REGULATORY REGIONS WERE ANALYZED BY METHYLATION-SPECIFIC PCR AND COMBINED BISULFITE RESTRICTION ANALYSIS. STE ANIMALS SHOWED INCREASED BDNF AND SYN PROTEIN EXPRESSION AND A HIGHER ACTIVITY OF BDNF II, IV, AND V PROMOTERS. IN CONTRAST, LTE ANIMALS DID NOT SHOW E INDUCTION OF NEUROTROPHINS. IN THESE ANIMALS, THE METHYLATION LEVELS OF REGULATORY SEQUENCES OF THE BDNF WERE HIGHER THAN IN THE STE ANIMALS IN A CPG ISLAND OF PROMOTER V AND IN THE CRE REGULATORY SITE LOCATED IN PROMOTER IV. WITH THIS EXPERIMENT, WE DETERMINED THAT A PROLONGED PERIOD OF HYPOESTROGENICITY DISRUPTS THE E-INDUCTION OF NEUROTROPHINS, AND WE POSTULATED THAT DNA METHYLATION IS ONE OF THE EPIGENETIC MECHANISMS THAT COULD EXPLAIN THE E-INSENSITIVITY OF THE BDNF AFTER A LONG PERIOD POST-OVX. 2014 11 5273 27 PROMOTER METHYLATION AND BDNF AND DAT1 GENE EXPRESSION PROFILES IN PATIENTS WITH DRUG ADDICTION. BACKGROUND: DRUG ADDICTION IS A BRAIN DISORDER THAT HAS NEGATIVE CONSEQUENCES FOR INDIVIDUALS AND SOCIETY. ADDICTIONS ARE CHRONIC RELAPSING DISEASES OF THE BRAIN THAT ARE CAUSED BY DIRECT DRUG-INDUCED EFFECTS AND PERSEVERING NEUROADAPTATIONS AT THE EPIGENETIC, NEUROPEPTIDE AND NEUROTRANSMITTER LEVELS. BECAUSE THE DOPAMINERGIC SYSTEM HAS A SIGNIFICANT ROLE IN DRUG ABUSE, THE PURPOSE OF THIS STUDY WAS TO ANALYZE THE METHYLATION AND EXPRESSION PROFILE OF BRAIN-DERIVED NEUROTROPHIC FACTOR (BDNF) AND DOPAMINE TRANSPORTER (DAT1) GENES IN INDIVIDUALS WITH DRUG ADDICTION. MATERIALS AND METHODS: BDNF AND DAT1 PROMOTER METHYLATION WERE INVESTIGATED WITH A METHYLATION-SPECIFIC POLYMERASE CHAIN REACTION (PCR) TECHNIQUE IN BLOOD SAMPLES FROM 75 INDIVIDUALS WITH DRUG ADDICTION AND 65 HEALTHY CONTROLS. THE EXPRESSION LEVELS OF BDNF AND DAT1 WERE ASSESSED IN 12 MRNA SAMPLES FROM THE BLOOD OF PATIENTS AND COMPARED TO THE SAMPLES OF HEALTHY CONTROLS (N = 12) WITH REAL-TIME QUANTITATIVE REVERSE TRANSCRIPTION PCR. RESULTS: NO SIGNIFICANT DIFFERENCES WERE FOUND IN THE METHYLATION OF BDNF AND DAT1 BETWEEN PATIENTS AND CONTROLS, BUT THE RELATIVE LEVELS OF EXPRESSION OF BDNF AND DAT1 MRNA DIFFERED SIGNIFICANTLY IN THE PATIENTS COMPARED TO CONTROLS (P < 0.0001). CONCLUSION: THESE RESULTS SHOWED THAT THE METHYLATION STATUS OF THE BDNF AND DAT1 GENES HAD NO SIGNIFICANT FUNCTION IN THE PROCESSES OF DRUG ADDICTION. 2015 12 6602 28 TWO KINDS OF TRANSCRIPTION FACTORS MEDIATE CHRONIC MORPHINE-INDUCED DECREASE IN MIR-105 IN MEDIAL PREFRONTAL CORTEX OF RATS. CHRONIC MORPHINE ADMINISTRATION ALTERS GENE EXPRESSION IN DIFFERENT BRAIN REGIONS, AN EFFECT WHICH MAY CONTRIBUTE TO PLASTIC CHANGES ASSOCIATED WITH ADDICTIVE BEHAVIOR. THIS CHANGE IN GENE EXPRESSION IS MOST POSSIBLY MEDIATED BY ADDICTIVE DRUG-INDUCED EPIGENETIC REMODELING OF GENE EXPRESSION PROGRAMS. OUR PREVIOUS STUDIES SHOWED THAT CHRONIC MORPHINE-INDUCED DECREASE OF MIR-105 IN THE MEDIAL PREFRONTAL CORTEX (MPFC) CONTRIBUTED TO CONTEXT-INDUCED RETRIEVAL OF MORPHINE WITHDRAWAL MEMORY. HOWEVER, HOW CHRONIC MORPHINE TREATMENT DECREASES MIR-105 IN THE MPFC STILL REMAINS UNKNOWN. THE PRESENT STUDY SHOWS THAT CHRONIC MORPHINE INDUCES ADDICTION-RELATED CHANGE IN MIR-105 IN THE MPFC VIA TWO KINDS OF TRANSCRIPTION FACTORS: THE FIRST TRANSCRIPTION FACTOR IS CREB ACTIVATED BY MU RECEPTORS-ERK-P90RSK SIGNALING PATHWAY AND THE SECOND TRANSCRIPTION FACTOR IS GLUCOCORTICOID RECEPTOR (GR), WHICH AS A NEGATIVE TRANSCRIPTION FACTOR, MEDIATES CHRONIC MORPHINE-INDUCED DECREASE IN MIR-105 IN THE MPFC OF RATS. 2022 13 5065 33 PHOTOPERIOD-INDUCED NEUROTRANSMITTER PLASTICITY DECLINES WITH AGING: AN EPIGENETIC REGULATION? NEUROPLASTICITY HAS CLASSICALLY BEEN UNDERSTOOD TO ARISE THROUGH CHANGES IN SYNAPTIC STRENGTH OR SYNAPTIC CONNECTIVITY. A NEWLY DISCOVERED FORM OF NEUROPLASTICITY, NEUROTRANSMITTER SWITCHING, INVOLVES CHANGES IN NEUROTRANSMITTER IDENTITY. CHRONIC EXPOSURE TO DIFFERENT PHOTOPERIODS ALTERS THE NUMBER OF DOPAMINE (TYROSINE HYDROXYLASE, TH+) AND SOMATOSTATIN (SST+) NEURONS IN THE PARAVENTRICULAR NUCLEUS (PAVN) OF THE HYPOTHALAMUS OF ADULT RATS AND RESULTS IN DISCRETE BEHAVIORAL CHANGES. HERE, WE INVESTIGATE WHETHER PHOTOPERIOD-INDUCED NEUROTRANSMITTER SWITCHING PERSISTS DURING AGING AND WHETHER EPIGENETIC MECHANISMS OF HISTONE ACETYLATION AND DNA METHYLATION MAY CONTRIBUTE TO THIS NEUROTRANSMITTER PLASTICITY. WE SHOW THAT THIS PLASTICITY IN RATS IS ROBUST AT 1 AND AT 3 MONTHS BUT REDUCED IN TH+ NEURONS AT 12 MONTHS AND COMPLETELY ABOLISHED IN BOTH TH+ AND SST+ NEURONS BY 18 MONTHS. DE NOVO EXPRESSION OF DNMT3A CATALYZING DNA METHYLATION AND ANTI-ACETYLH3 ASSESSING HISTONE 3 ACETYLATION WERE OBSERVED FOLLOWING SHORT-DAY PHOTOPERIOD EXPOSURE IN BOTH TH+ AND SST+ NEURONS AT 1 AND 3 MONTHS WHILE AN OVERALL INCREASE IN DNMT3A IN SST+ NEURONS PARALLELED NEUROPLASTICITY REDUCTION AT 12 AND 18 MONTHS. HISTONE ACETYLATION INCREASED IN TH+ NEURONS AND DECREASED IN SST+ NEURONS FOLLOWING SHORT-DAY EXPOSURE AT 3 MONTHS WHILE THE TOTAL NUMBER OF ANTI-ACETYLH3+ PAVN NEURONS REMAINED CONSTANT. RECIPROCAL HISTONE ACETYLATION IN TH+ AND SST+ NEURONS INDICATES THE IMPORTANCE OF STUDYING EPIGENETIC REGULATION AT THE CIRCUIT LEVEL FOR IDENTIFIED CELL PHENOTYPES. THE FINDINGS MAY BE USEFUL FOR DEVELOPING APPROACHES FOR NONINVASIVE TREATMENT OF DISORDERS CHARACTERIZED BY NEUROTRANSMITTER DYSFUNCTION. 2020 14 2672 30 ETHANOL-INDUCED EPIGENETIC REGULATIONS AT THE BDNF GENE IN C57BL/6J MICE. HIGH ETHANOL INTAKE IS WELL KNOWN TO INDUCE BOTH ANXIOLYTIC AND ANXIOGENIC EFFECTS, IN CORRELATION WITH CHROMATIN REMODELING IN THE AMYGDALOID BRAIN REGION AND DEFICITS IN CELL PROLIFERATION AND SURVIVAL IN THE HIPPOCAMPUS OF RODENTS. WHETHER ONLY MODERATE BUT CHRONIC ETHANOL INTAKE IN C57BL/6J MICE COULD ALSO HAVE AN IMPACT ON CHROMATIN REMODELING AND NEUROPLASTICITY WAS ADDRESSED HERE. CHRONIC ETHANOL CONSUMPTION IN A FREE CHOICE PARADIGM WAS FOUND TO INDUCE MARKED CHANGES IN THE EXPRESSION OF GENES IMPLICATED IN NEURAL DEVELOPMENT AND HISTONE POST-TRANSLATIONAL MODIFICATIONS IN THE MOUSE HIPPOCAMPUS. TRANSCRIPTS ENCODING NEURAL BHLH ACTIVATORS AND THOSE FROM BDNF EXONS II, III AND VI WERE UPREGULATED, WHEREAS THOSE FROM BDNF EXON VIII AND HDACS WERE DOWNREGULATED BY ETHANOL COMPARED WITH WATER CONSUMPTION. THESE ETHANOL-INDUCED CHANGES WERE ASSOCIATED WITH ENRICHMENT IN BOTH ACETYLATED H3 AT BDNF PROMOTER PVI AND TRIMETHYLATED H3 AT PII AND PIII. CONVERSELY, ACETYLATED H3 AT PIII AND PVIII AND TRIMETHYLATED H3 AT PVIII WERE DECREASED IN ETHANOL-EXPOSED MICE. IN PARALLEL, HIPPOCAMPAL BRAIN-DERIVED NEUROTROPHIC FACTOR (BDNF) LEVELS AND TRKB-MEDIATED NEUROGENESIS IN THE DENTATE GYRUS WERE SIGNIFICANTLY ENHANCED BY ETHANOL CONSUMPTION. THESE RESULTS SUGGEST THAT, IN C57BL/6J MICE, CHRONIC AND MODERATE ETHANOL INTAKE PRODUCES MARKED EPIGENETIC CHANGES UNDERLYING BDNF OVEREXPRESSION AND DOWNSTREAM HIPPOCAMPAL NEUROGENESIS. 2015 15 1330 36 DEPRESSIVE-LIKE BEHAVIORS ARE REGULATED BY NOX1/NADPH OXIDASE BY REDOX MODIFICATION OF NMDA RECEPTOR 1. INVOLVEMENT OF REACTIVE OXYGEN SPECIES (ROS) HAS BEEN SUGGESTED IN THE DEVELOPMENT OF PSYCHIATRIC DISORDERS. NOX1 IS A NONPHAGOCYTIC FORM OF NADPH OXIDASE WHOSE EXPRESSION IN THE NERVOUS SYSTEM IS NEGLIGIBLE COMPARED WITH OTHER NOX ISOFORMS. HOWEVER, NOX1-DERIVED ROS INCREASE INFLAMMATORY PAIN AND TOLERANCE TO OPIOID ANALGESIA. TO CLARIFY THE ROLE OF NOX1 IN THE BRAIN, WE EXAMINED DEPRESSIVE-LIKE BEHAVIORS IN MICE DEFICIENT IN NOX1 (NOX1(-/Y)). DEPRESSIVE-LIKE BEHAVIORS INDUCED BY CHRONIC SOCIAL DEFEAT STRESS OR ADMINISTRATION OF CORTICOSTERONE (CORT) WERE SIGNIFICANTLY AMELIORATED IN NOX1(-/Y) GENERATION OF ROS WAS SIGNIFICANTLY ELEVATED IN THE PREFRONTAL CORTEX (PFC) OF MICE ADMINISTRATED WITH CORT, WHILE NOX1 MRNA WAS UPREGULATED ONLY IN THE VENTRAL TEGMENTAL AREA (VTA) AMONG BRAIN AREAS RESPONSIBLE FOR EMOTIONAL BEHAVIORS. DELIVERY OF MIRNA AGAINST NOX1 TO VTA RESTORED CORT-INDUCED DEPRESSIVE-LIKE BEHAVIORS IN WILD-TYPE (WT) LITTERMATES. ADMINISTRATION OF CORT TO WT, BUT NOT TO NOX1(-/Y), SIGNIFICANTLY REDUCED TRANSCRIPT LEVELS OF BRAIN-DERIVED NEUROTROPHIC FACTOR (BDNF), WITH A CONCOMITANT INCREASE IN DNA METHYLATION OF THE PROMOTER REGIONS IN BDNF DELIVERY OF MIRNA AGAINST NOX1 TO VTA RESTORED THE LEVEL OF BDNF MRNA IN WT PFC. REDOX PROTEOME ANALYSES DEMONSTRATED THAT NMDA RECEPTOR 1 (NR1) WAS AMONG THE MOLECULES REDOX REGULATED BY NOX1. IN CULTURED CORTICAL NEURONS, HYDROGEN PEROXIDE SIGNIFICANTLY SUPPRESSED NMDA-INDUCED UPREGULATION OF BDNF TRANSCRIPTS IN NR1-EXPRESSING CELLS BUT NOT IN CELLS HARBORING MUTANT NR1 (C744A). TOGETHER, THESE FINDINGS SUGGEST A KEY ROLE OF NOX1 IN DEPRESSIVE-LIKE BEHAVIORS THROUGH NR1-MEDIATED EPIGENETIC MODIFICATION OF BDNF IN THE MESOPREFRONTAL PROJECTION.SIGNIFICANCE STATEMENT NADPH OXIDASE IS A SOURCE OF REACTIVE OXYGEN SPECIES (ROS) THAT HAVE BEEN IMPLICATED IN THE PATHOGENESIS OF VARIOUS NEUROLOGICAL DISORDERS. WE PRESENTLY SHOWED THE INVOLVEMENT OF A NONPHAGOCYTIC TYPE OF NADPH OXIDASE, NOX1, IN MAJOR DEPRESSIVE DISORDERS, INCLUDING BEHAVIORAL, BIOCHEMICAL, AND ANATOMICAL CHANGES IN MICE. THE OXIDATION OF NR1 BY NOX1-DERIVED ROS WAS DEMONSTRATED IN PREFRONTAL CORTEX (PFC), WHICH MAY BE CAUSALLY LINKED TO THE DOWNREGULATION OF BDNF, PROMOTING DEPRESSIVE-LIKE BEHAVIORS. GIVEN THAT NOX1 IS UPREGULATED ONLY IN VTA BUT NOT IN PFC, MESOCORTICAL PROJECTIONS APPEAR TO PLAY A CRUCIAL ROLE IN NOX1-DEPENDENT DEPRESSIVE-LIKE BEHAVIORS. OUR STUDY IS THE FIRST TO PRESENT THE POTENTIAL MOLECULAR MECHANISM UNDERLYING THE DEVELOPMENT OF MAJOR DEPRESSION THROUGH THE NOX1-INDUCED OXIDATION OF NR1 AND EPIGENETIC MODIFICATION OF BDNF. 2017 16 2246 24 EPIGENETIC MODULATION OF INFLAMMATION AND SYNAPTIC PLASTICITY PROMOTES RESILIENCE AGAINST STRESS IN MICE. MAJOR DEPRESSIVE DISORDER IS ASSOCIATED WITH ABNORMALITIES IN THE BRAIN AND THE IMMUNE SYSTEM. CHRONIC STRESS IN ANIMALS SHOWED THAT EPIGENETIC AND INFLAMMATORY MECHANISMS PLAY IMPORTANT ROLES IN MEDIATING RESILIENCE AND SUSCEPTIBILITY TO DEPRESSION. HERE, THROUGH A HIGH-THROUGHPUT SCREENING, WE IDENTIFY TWO PHYTOCHEMICALS, DIHYDROCAFFEIC ACID (DHCA) AND MALVIDIN-3'-O-GLUCOSIDE (MAL-GLUC) THAT ARE EFFECTIVE IN PROMOTING RESILIENCE AGAINST STRESS BY MODULATING BRAIN SYNAPTIC PLASTICITY AND PERIPHERAL INFLAMMATION. DHCA/MAL-GLUC ALSO SIGNIFICANTLY REDUCES DEPRESSION-LIKE PHENOTYPES IN A MOUSE MODEL OF INCREASED SYSTEMIC INFLAMMATION INDUCED BY TRANSPLANTATION OF HEMATOPOIETIC PROGENITOR CELLS FROM STRESS-SUSCEPTIBLE MICE. DHCA REDUCES PRO-INFLAMMATORY INTERLEUKIN 6 (IL-6) GENERATIONS BY INHIBITING DNA METHYLATION AT THE CPG-RICH IL-6 SEQUENCES INTRONS 1 AND 3, WHILE MAL-GLUC MODULATES SYNAPTIC PLASTICITY BY INCREASING HISTONE ACETYLATION OF THE REGULATORY SEQUENCES OF THE RAC1 GENE. PERIPHERAL INFLAMMATION AND SYNAPTIC MALADAPTATION ARE IN LINE WITH NEWLY HYPOTHESIZED CLINICAL INTERVENTION TARGETS FOR DEPRESSION THAT ARE NOT ADDRESSED BY CURRENTLY AVAILABLE ANTIDEPRESSANTS. 2018 17 4499 33 MORPHINE WITHDRAWAL PRODUCES ERK-DEPENDENT AND ERK-INDEPENDENT EPIGENETIC MARKS IN NEURONS OF THE NUCLEUS ACCUMBENS AND LATERAL SEPTUM. EPIGENETIC CHANGES SUCH AS COVALENT MODIFICATIONS OF HISTONE PROTEINS REPRESENT COMPLEX MOLECULAR SIGNATURES THAT PROVIDE A CELLULAR MEMORY OF PREVIOUSLY EXPERIENCED STIMULI WITHOUT IRREVERSIBLE CHANGES OF THE GENETIC CODE. IN THIS STUDY WE SHOW THAT NEW GENE EXPRESSION INDUCED IN VIVO BY MORPHINE WITHDRAWAL OCCURS WITH CONCOMITANT EPIGENETIC MODIFICATIONS IN BRAIN REGIONS CRITICALLY INVOLVED IN DRUG-DEPENDENT BEHAVIORS. WE FOUND THAT NALOXONE-PRECIPITATED WITHDRAWAL, BUT NOT CHRONIC MORPHINE ADMINISTRATION, CAUSED A STRONG INDUCTION OF PHOSPHO-HISTONE H3 IMMUNOREACTIVITY IN THE NUCLEUS ACCUMBENS (NAC) SHELL/CORE AND IN THE LATERAL SEPTUM (LS), A CHANGE THAT WAS ACCOMPANIED BY AUGMENTED H3 ACETYLATION (LYS14) IN NEURONS OF THE NAC SHELL. MORPHINE WITHDRAWAL INDUCED THE PHOSPHORYLATION OF THE EPIGENETIC FACTOR METHYL-CPG-BINDING PROTEIN 2 (MECP2) IN SER421 BOTH IN THE LS AND THE NAC SHELL. THESE EPIGENETIC CHANGES WERE ACCOMPANIED BY THE ACTIVATION OF MEMBERS OF THE ERK PATHWAY AS WELL AS INCREASED EXPRESSION OF THE IMMEDIATE EARLY GENES (IEG) C-FOS AND ACTIVITY-REGULATED CYTOSKELETON-ASSOCIATED PROTEIN (ARC/ARG3.1). USING A PHARMACOLOGICAL APPROACH, WE FOUND THAT H3 PHOSPHORYLATION AND IEG EXPRESSION WERE PARTIALLY DEPENDENT ON ERK ACTIVATION, WHILE MECP2 PHOSPHORYLATION WAS FULLY ERK-INDEPENDENT. THESE FINDINGS PROVIDE NEW IMPORTANT INFORMATION ON THE ROLE OF THE ERK PATHWAY IN THE REGULATION OF EPIGENETIC MARKS AND GENE EXPRESSION THAT MAY CONCUR TO REGULATE IN VIVO THE CELLULAR CHANGES UNDERLYING THE ONSET OF THE OPIOID WITHDRAWAL SYNDROME. 2013 18 5832 24 STRESS-INDUCED EPIGENETIC CHANGES IN HIPPOCAMPAL MKP-1 PROMOTE PERSISTENT DEPRESSIVE BEHAVIORS. CHRONIC STRESS INDUCES PERSISTENT DEPRESSIVE BEHAVIORS. STRESS-INDUCED TRANSCRIPTIONAL ALTERATION OVER THE HOMEOSTATIC RANGE IN STRESS HORMONE-SENSITIVE BRAIN REGIONS IS BELIEVED TO UNDERLIE LONG-LASTING DEPRESSIVE BEHAVIORS. HOWEVER, THE DETAILED MECHANISMS BY WHICH CHRONIC STRESS CAUSES THOSE ADAPTIVE CHANGES ARE NOT CLEARLY UNDERSTOOD. IN THE PRESENT STUDY, WE INVESTIGATED WHETHER EPIGENETIC CHANGES REGULATE STRESS-INDUCED DEPRESSIVE BEHAVIORS. WE FOUND THAT CHRONIC STRESS IN MICE DOWNREGULATES THE EPIGENETIC FACTORS HDAC2 AND SUV39H1 IN THE HIPPOCAMPUS. A SERIES OF FOLLOW-UP ANALYSES INCLUDING CHIP ASSAY AND SIRNA-MEDIATED FUNCTIONAL ANALYSES REVEAL THAT GLUCOCORTICOIDS RELEASED BY STRESS CUMULATIVELY INCREASE MKP-1 EXPRESSION IN THE HIPPOCAMPUS, AND INCREASED MKP-1 THEN DEBILITATES P-CREB AND PPARGAMMA, WHICH IN TURN SUPPRESS THE EPIGENETIC FACTORS HDAC2 AND SUV39H1. FURTHERMORE, HDAC2 AND SUV39H1 NORMALLY SUPPRESS THE TRANSCRIPTION OF THE MKP-1, AND THEREFORE THE REDUCED EXPRESSION OF HDAC2 AND SUV39H1 INCREASES MKP-1 EXPRESSION. ACCORDINGLY, REPEATED STRESS PROGRESSIVELY STRENGTHENS A VICIOUS CYCLE OF THE MKP-1 SIGNALING CASCADE THAT FACILITATES DEPRESSIVE BEHAVIORS. THESE RESULTS SUGGEST THAT THE HIPPOCAMPAL STRESS ADAPTATION SYSTEM COMPRISING HDAC2/SUV39H1-REGULATED MKP-1 SIGNALING NETWORK DETERMINES THE VULNERABILITY TO CHRONIC STRESS AND THE MAINTENANCE OF DEPRESSIVE BEHAVIORS. 2019 19 6156 19 THE GENETIC INFLUENCE ON THE CORTICAL PROCESSING OF EXPERIMENTAL PAIN AND THE MODERATING EFFECT OF PAIN STATUS. BACKGROUND: RESEARCH SUGGESTS THAT THE COMT VAL(158)MET, BDNF VAL(66)MET AND OPRM1 A(118)G POLYMORPHISMS MODERATE THE EXPERIENCE OF PAIN. IN ORDER TO OBTAIN EXPERIMENTAL CONFIRMATION AND EXTENSION OF FINDINGS, CORTICAL PROCESSING OF EXPERIMENTALLY-INDUCED PAIN WAS USED. METHOD: A SAMPLE OF 78 INDIVIDUALS WITH CHRONIC LOW BACK PAIN COMPLAINTS AND 37 HEALTHY CONTROLS UNDERWENT EEG REGISTRATION. EVENT-RELATED POTENTIALS WERE MEASURED IN RESPONSE TO ELECTRICAL NOCICEPTIVE STIMULI AND MODERATION BY COMT VAL(158)MET, BDNF VAL(66)MET AND OPRM1 A(118)G POLYMORPHISMS WAS ASSESSED. RESULTS: GENETIC VARIATION DID NOT HAVE A DIRECT EFFECT ON CORTICAL PROCESSING OF EXPERIMENTAL PAIN. HOWEVER, GENETIC EFFECTS (COMT VAL(158)MET AND BDNF VAL(66)MET) ON EXPERIMENTAL PAIN WERE MODERATED BY THE PRESENCE OF CHRONIC PAIN. IN THE PRESENCE OF CHRONIC PAIN, THE COMT MET ALLELE AND THE BDNF MET ALLELE AUGMENTED CORTICAL PAIN PROCESSING, WHILST REDUCING PAIN PROCESSING IN PAIN-FREE CONTROLS. NO SIGNIFICANT EFFECTS WERE FOUND CONCERNING THE OPRM1 A(118)G POLYMORPHISM. CONCLUSIONS: THE CURRENT STUDY SUGGESTS THAT CHRONIC EXPERIENCE OF PAIN ENHANCES GENETIC SENSITIVITY TO EXPERIMENTALLY INDUCED MILDLY PAINFUL STIMULI, POSSIBLY THROUGH A PROCESS OF EPIGENETIC MODIFICATION. 2010 20 998 36 CHRONIC SUBCONVULSIVE ACTIVITY DURING EARLY POSTNATAL LIFE PRODUCES AUTISTIC BEHAVIOR IN THE ABSENCE OF NEUROTOXICITY IN THE JUVENILE WEANLING PERIOD. THE DIAGNOSIS OF AUTISM SPECTRUM DISORDER (ASD) VARIES FROM VERY MILD TO SEVERE SOCIAL AND COGNITIVE IMPAIRMENTS. WE HYPOTHESIZED THAT EPIGENETIC SUBCONVULSIVE ACTIVITY IN EARLY POSTNATAL LIFE MAY CONTRIBUTE TO THE DEVELOPMENT OF AUTISTIC BEHAVIOR IN A SEX-RELATED MANNER. LOW DOSES OF KAINIC ACID (KA) (25-100 MUG) WERE ADMINISTERED TO RAT PUPS FOR 15 DAYS BEGINNING ON POSTNATAL (P) DAY 6 TO CHRONICALLY ELEVATE NEURONAL ACTIVITY. A BATTERY OF CLASSICAL AND NOVEL BEHAVIORAL TESTS WAS USED, AND SEX DIFFERENCES WERE OBSERVED. OUR NOVEL OPEN HANDLING TEST REVEALED THAT ASD MALES NOSE POKED MORE OFTEN AND ASD FEMALES CLIMBED AND ESCAPED MORE FREQUENTLY WITH AGE. IN THE SOCIAL INTERACTION TEST, ASD MALES WERE LESS SOCIAL THAN ASD FEMALES WHO WERE MORE ANXIOUS IN HANDLING AND ELEVATED PLUS MAZE (EPM) TASKS. TO EVALUATE GROUP DYNAMICS, SIBLING AND NON-SIBLING CONTROL AND EXPERIMENTAL ANIMALS EXPLORED 3 DIFFERENT SHAPED NOVEL SOCIAL ENVIRONMENTS. CONTROL PUPS HUDDLED QUICKLY AND MORE FREQUENTLY IN ALL ENVIRONMENTS WHETHER THEY SOCIALIZED WITH LITTERMATES OR NON-SIBLINGS COMPARED TO ASD GROUPS. NON-SIBLING ASD PUPS WERE ERRATIC AND HUDDLED IN SMALLER GROUPS. IN THE OBJECT RECOGNITION TEST, ONLY ASD MALES SPENT LESS TIME WITH THE NOVEL OBJECT COMPARED TO CONTROL PUPS. DATA SUGGEST THAT CHRONIC SUBCONVULSIVE ACTIVITY IN EARLY POSTNATAL LIFE LEADS TO AN ASD PHENOTYPE IN THE ABSENCE OF CELL DEATH. MALES WERE MORE SUSCEPTIBLE TO DEVELOPING ASOCIAL BEHAVIORS AND COGNITIVE PATHOLOGIES, WHEREAS FEMALES WERE PRONE TO HIGHER LEVELS OF HYPERACTIVITY AND ANXIETY, VALIDATING OUR POSTNATAL ASD MODEL APPARENT IN THE PRE-JUVENILE PERIOD. 2019