1 510 122 ASSOCIATION OF RASGRF1 METHYLATION WITH EPILEPTIC SEIZURES. DNA METHYLATION, ONE OF THE MECHANISMS OF EPIGENETIC REGULATION, HAS BEEN SUGGESTED TO BE RELATED WITH EPILEPSY. RASGRF1 IS A PATERNALLY IMPRINTED GENE AND HAS A DIFFERENTIALLY METHYLATED REGION (DMR) AT THE PROMOTER THAT CAN SILENCE GENE EXPRESSION. WE HAVE PREVIOUSLY OBSERVED THE DOWN-REGULATION OF RASGRF1 IN THE TEMPORAL NEOCORTEX OF EPILEPSY PATIENTS AND IN THE HIPPOCAMPUS OF EPILEPTIC ANIMALS. HERE, WE FURTHER EXPLORED THE DYNAMIC CHANGE (1-DAY ACUTE PERIOD, 10-DAY LATENT PERIOD AND 45-DAY CHRONIC PHASE) OF DNA METHYLATION AND RASGRF1 EXPRESSION AFTER ACUTE EPILEPTIC SEIZURES IN KAINIC ACID (KA)-TREATED MICE, AND WE OBSERVED THE IMPACT OF N-PHTHALYL-L-TRYPTOPHAN (RG108), A DNA METHYLTRANSFERASE (DNMT) INHIBITOR, ON AN ACUTE EPILEPTIC MODEL BY POLYMERASE CHAIN REACTION (PCR), WESTERN BLOTTING, AND BISULFITE SEQUENCING PCR (BSP). THE RESULTS DIRECTLY SHOWED THAT THE METHYLATION OF THE RASGRF1 PROMOTER GRADUALLY INCREASED AND REACHED A MAXIMAL LEVEL AT THE LATENT PERIOD, WITH SUBSEQUENT SUPPRESSION OF RASGRF1 MRNA AND PROTEIN EXPRESSION LEVELS, WHICH REACHED A MINIMUM LEVEL IN THE CHRONIC PHASE. RG108 INHIBITED THE INCREASED METHYLATION OF THE RASGRF1 GENE, WITH SIGNIFICANT INHIBITION OCCURRING AT THE LATENT PERIOD, AND RESTORED RASGRF1 EXPRESSION LEVELS IN THE CHRONIC PHASE. IN ADDITION, WE DEMONSTRATED THAT RG108 COULD SUPPRESS ACUTE EPILEPTIC SEIZURES IN KA-TREATED MICE AND EPILEPTIC DISCHARGES IN 4-AMINOPYRIDINE (4-AP)-TREATED HIPPOCAMPAL SLICES. THESE FINDINGS DEMONSTRATE THAT RASGRF1 IS CLOSELY ASSOCIATED WITH EPILEPSY VIA THE ABERRANT METHYLATION OF RASGRF1, AND REGULATING THE METHYLATION STATUS OF RELEVANT GENES MIGHT BE AN INTRIGUING TOPIC IN FUTURE RESEARCH ON EPILEPSY. 2017 2 5348 64 RASGRF1, A POTENTIAL METHYLATIC MEDIATOR OF ANTI-EPILEPTOGENESIS? EPILEPTOGENESIS, INDUCED BY STATUS EPILEPTICUS (SE), IS A CHRONIC PROCESS, AND INTERVENTION IN THIS PROGRESS MAY PREVENT CHRONIC EPILEPSY. IT HAS BEEN PROPOSED THAT DNA METHYLATION MIGHT BE RELATED WITH EPILEPTOGENESIS. RASGRF1 HAS A DIFFERENTIALLY METHYLATED REGION AT THE PROMOTER WHICH CAN SILENCE GENE EXPRESSION. WE HAVE PREVIOUSLY OBSERVED THE DOWN-REGULATION OF RASGRF1 IN EPILEPSY PATIENTS AND PROVED THAT HYPERMETHYLATION OF RASGRF1 REACHES MAXIMAL LEVEL AT THE LATENT PERIOD IN MICE AFTER KAINATE-INDUCED SE (KA MICE), WITH CORRESPONDING ALTERATION OF RASGRF1 EXPRESSION. IN THE PRESENT STUDY, N-PHTHALYL-L-TRYPTOPHAN (RG108), A DNA METHYLTRANSFERASE INHIBITOR, WAS APPLIED IN KA MICE AT LATENT PHASE AND THE BEHAVIOR, ELECTROENCEPHALOGRAM AND PATHOLOGICAL CHANGES WERE OBSERVED IN CHRONIC PHASE. METHYLATION AND EXPRESSION OF RASGRF1 WERE DETERMINED BY POLYMERASE CHAIN REACTION (PCR), WESTERN BLOTTING, AND BISULFITE SEQUENCING PCR. THE RESULTS SHOWED THAT THE INCIDENCE OF SPONTANEOUS RECURRENT SEIZURES (SRS) WAS SIGNIFICANTLY LOWER IN THE RG108 GROUP THAN THE NORMAL SALINE (NS) GROUP. SUBGROUP ANALYSIS SHOWED SIGNIFICANT HYPERMETHYLATION AND LOWER EXPRESSION OF RASGRF1 IN THE RG108-SRS SUBGROUP AND THE NS-SRS SUBGROUP BUT NOT IN THE RG108-NSRS (NO SRS) SUBGROUP AND THE NS-NSRS SUBGROUP COMPARED WITH THE CONTROL GROUP. NO SIGNIFICANT DIFFERENCE WAS FOUND BETWEEN THE RG108-SRS AND NS-SRS SUBGROUPS. MEANWHILE, HIPPOCAMPAL NEURONAL LOSS WAS OBSERVED IN RG108-SRS AND NS-SRS SUBGROUPS. WE THUS DEMONSTRATED THAT RG108 COULD MODIFY THE PROGRESSION OF EPILEPTOGENESIS AFTER KA INDUCED SE AND PREVENT CHRONIC EPILEPSY. MEANWHILE, HYPERMETHYLATION OF RASGRF1 AFTER KA INDUCED SE COULD BE REVERSED WITH CORRESPONDING CHANGES OF RASGRF1 EXPRESSION. ADDITIONALLY, WE SPECULATED THAT RASGRF1 MIGHT BE A POTENTIAL EPIGENETIC MEDIATOR IN EPILEPTOGENESIS AND CHRONIC EPILEPSY. 2018 3 2300 34 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 4 5345 47 RAPID CHANGES IN EXPRESSION OF CLASS I AND IV HISTONE DEACETYLASES DURING EPILEPTOGENESIS IN MOUSE MODELS OF TEMPORAL LOBE EPILEPSY. A PROMINENT ROLE OF EPIGENETIC MECHANISMS IN MANIFESTATION OF EPILEPSY HAS BEEN PROPOSED. THUS ALTERED HISTONE H3 AND H4 ACETYLATION HAS BEEN DEMONSTRATED IN EXPERIMENTAL MODELS OF TEMPORAL LOBE EPILEPSY (TLE). WE NOW INVESTIGATED CHANGES IN THE EXPRESSION OF THE CLASS I AND CLASS IV HISTONE DEACETYLASES (HDAC) IN TWO COMPLEMENTARY MOUSE TLE MODELS. UNILATERAL INTRAHIPPOCAMPAL INJECTION OF KAINIC ACID (KA) INDUCED A STATUS EPILEPTICUS LASTING 6 TO 24H, DEVELOPMENT OF SPONTANEOUS LIMBIC SEIZURES (2 TO 3 DAYS AFTER KA INJECTION) AND CHRONIC EPILEPSY, AS REVEALED BY TELEMETRIC RECORDINGS OF THE EEGS. MICE WERE KILLED AT DIFFERENT INTERVALS AFTER KA INJECTION AND EXPRESSION OF HDAC MRNAS WAS INVESTIGATED BY IN SITU HYBRIDIZATION. WE OBSERVED MARKED DECREASES IN THE EXPRESSION OF HDACS 1, 2 AND 11 (BY UP TO 75%) IN THE GRANULE CELL AND PYRAMIDAL CELL LAYERS OF THE HIPPOCAMPUS DURING THE ACUTE STATUS EPILEPTICUS (2 TO 6H AFTER KA INJECTION). THIS WAS FOLLOWED BY INCREASED EXPRESSION OF ALL CLASS I HDAC MRNAS IN ALL PRINCIPAL CELL LAYERS OF THE HIPPOCAMPUS AFTER 12 TO 48 H. IN THE CHRONIC PHASE, 14 AND 28 DAYS AFTER KA, ONLY MODEST INCREASES IN THE EXPRESSION OF HDAC1 MRNA WERE OBSERVED IN GRANULE AND PYRAMIDAL CELLS. IMMUNOHISTOCHEMISTRY USING AN ANTIBODY DETECTING HDAC2 REVEALED RESULTS CONSISTENT WITH THE MRNA DATA AND INDICATES ALSO EXPRESSION IN GLIAL CELLS ON THE INJECTION SIDE. SIMILAR CHANGES AS SEEN IN THE KA MODEL WERE OBSERVED AFTER A PILOCARPINE-INDUCED STATUS EPILEPTICUS EXCEPT THAT DECREASES IN HDACS 2, 3 AND 8 WERE ALSO SEEN AT THE CHRONIC 28 DAY INTERVAL. THE PROMINENT DECREASES IN HDAC EXPRESSION DURING STATUS EPILEPTICUS ARE CONSISTENT WITH THE PREVIOUSLY DEMONSTRATED INCREASED EXPRESSION OF NUMEROUS PROTEINS AND WITH THE AUGMENTED ACETYLATION OF HISTONE H4. IT IS SUGGESTED THAT RESPECTIVE PUTATIVE GENE PRODUCTS COULD FACILITATE PROCONVULSIVE AS WELL AS ANTICONVULSIVE MECHANISMS. THE INCREASED EXPRESSION OF ALL CLASS I HDACS DURING THE "SILENT PHASE", ON THE OTHER HAND, MAY BE RELATED TO DECREASED HISTONE ACETYLATION, WHICH COULD CAUSE A DECREASE IN EXPRESSION OF CERTAIN PROTEINS, A MECHANISM THAT COULD ALSO PROMOTE EPILEPTOGENESIS. THUS, ADDRESSING HDAC EXPRESSION MAY HAVE A THERAPEUTIC POTENTIAL IN INTERFERING WITH A STATUS EPILEPTICUS AND WITH THE MANIFESTATION OF TLE. 2015 5 219 31 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 6 2755 35 EXPRESSION OF CLASS II HISTONE DEACETYLASES IN TWO MOUSE MODELS OF TEMPORAL LOBE EPILEPSY. EPIGENETIC MECHANISMS LIKE ALTERED HISTONE ACETYLATION MAY HAVE A CRUCIAL ROLE IN EPILEPTOGENESIS. IN TWO MOUSE MODELS OF TEMPORAL LOBE EPILEPSY, WE INVESTIGATED CHANGES IN THE EXPRESSION OF CLASS II HISTONE DEACETYLASES (HDAC), A GROUP OF SIGNAL TRANSDUCERS THAT SHUTTLE BETWEEN NUCLEUS AND CYTOPLASM. INTRAHIPPOCAMPAL INJECTION OF KAINIC ACID (KA) INDUCED A STATUS EPILEPTICUS, DEVELOPMENT OF SPONTANEOUS SEIZURES (AFTER 3 DAYS), AND FINALLY CHRONIC EPILEPSY AND GRANULE CELL DISPERSION. EXPRESSION OF CLASS II HDAC MRNAS WAS INVESTIGATED AT DIFFERENT TIME INTERVALS AFTER KA INJECTION IN THE GRANULE CELL LAYERS AND IN SECTORS CA1 AND CA3 CONTRALATERAL TO THE SITE OF KA INJECTION LACKING NEURODEGENERATION. INCREASED EXPRESSION OF HDAC5 AND 9 MRNAS COINCIDED WITH PRONOUNCED GRANULE CELL DISPERSION IN THE KA-INJECTED HIPPOCAMPUS AT LATE INTERVALS (14-28 DAYS AFTER KA) AND EQUALLY AFFECTED BOTH HDAC9 SPLICE VARIANTS. IN CONTRAST, IN THE PILOCARPINE MODEL (SHOWING NO GRANULE CELL DISPERSION), WE OBSERVED DECREASES IN THE EXPRESSION OF HDAC5 AND 9 AT THE SAME TIME INTERVALS. BEYOND THIS, STRIKING SIMILARITIES BETWEEN BOTH TEMPORAL LOBE EPILEPSY MODELS SUCH AS FAST DECREASES IN HDAC7 AND 10 MRNAS DURING THE ACUTE STATUS EPILEPTICUS WERE OBSERVED, NOTABLY ALSO IN THE CONTRALATERAL HIPPOCAMPUS NOT AFFECTED BY NEURODEGENERATION. THE PARTICULAR PATTERNS OF HDAC MRNA EXPRESSION SUGGEST A ROLE IN EPILEPTOGENESIS AND GRANULE CELL DISPERSION. REDUCED EXPRESSION OF HDACS MAY RESULT IN INCREASED EXPRESSION OF PRO- AND ANTICONVULSIVE PROTEINS. ON THE OTHER HAND, EXPORT OF HDACS FROM THE NUCLEUS INTO THE CYTOPLASM COULD ALLOW FOR DEACETYLATION OF CYTOPLASMATIC PROTEINS INVOLVED IN AXONAL AND DENDRITIC REMODELING, LIKE GRANULE CELL DISPERSION. HDAC 5 AND HDAC 9 EXPRESSION IS HIGHLY INCREASED IN GRANULE CELLS OF THE KA-INJECTED HIPPOCAMPUS AND PARALLELS GRANULE CELL DISPERSION. BOTH HDACS ARE THOUGHT TO BE TARGETED TO THE CYTOPLASM AND TO ACT THERE BY DEACETYLATING CYTOPLASMATIC (E.G. CYTOSCELETON-RELATED) PROTEINS. 2016 7 1831 37 EFFECTS OF MATERNAL SEPARATION AND ANTIDEPRESSANT DRUG ON EPIGENETIC REGULATION OF THE BRAIN-DERIVED NEUROTROPHIC FACTOR EXON I PROMOTER IN THE ADULT RAT HIPPOCAMPUS. AIM: EARLY LIFE STRESS CAN INDUCE EPIGENETIC CHANGES THROUGH GENETIC AND ENVIRONMENTAL INTERACTIONS AND IS A RISK FACTOR FOR DEPRESSION. BRAIN-DERIVED NEUROTROPHIC FACTOR (BDNF) HAS BEEN IMPLICATED IN THE PATHOPHYSIOLOGY OF DEPRESSION AND ANTIDEPRESSANT DRUG ACTION. WE INVESTIGATED EPIGENETIC CHANGES AT THE BDNF EXON I PROMOTER IN THE HIPPOCAMPUS OF ADULT RATS SUBJECTED TO MATERNAL SEPARATION (MS) DURING EARLY LIFE AND TREATED WITH AN ANTIDEPRESSANT DRUG AS ADULTS. METHODS: RAT PUPS WERE SUBJECTED TO MS FROM POSTNATAL DAY 1 TO 21 AND RECEIVED CHRONIC ESCITALOPRAM (ESC) AS ADULTS. WE ASSESSED THE EFFECTS OF MS AND ESC ON BDNF EXON I AND DNA METHYLTRANSFERASES (DNMT) MRNA LEVELS (QUANTITATIVE REVERSE-TRANSCRIPTION POLYMERASE CHAIN REACTION), ACETYLATED HISTONE H3, AND MECP2 BINDING TO THE BDNF PROMOTER I (CHROMATIN IMMUNOPRECIPITATION FOLLOWED BY REAL-TIME POLYMERASE CHAIN REACTION), AND BDNF PROTEIN LEVELS (ENZYME-LINKED IMMUNOSORBENT ASSAY). RESULTS: THE LEVELS OF BDNF PROTEIN, EXON I MRNA, HISTONE H3 ACETYLATION, AND DNMT1 AND DNMT3A MRNA WERE ALTERED IN THE MS GROUP COMPARED WITH THE CONTROL GROUP. SIGNIFICANT DECREASES WERE OBSERVED IN THE BDNF PROTEIN, EXON I MRNA, AND HISTONE H3 ACETYLATION LEVELS AND THERE WERE SIGNIFICANT INCREASES IN DNMT1 AND DNMT3A MRNA LEVELS. THE COMPARISON BETWEEN THE MS + ESC AND MS GROUPS REVEALED SIGNIFICANT INCREASES IN BDNF PROTEIN, EXON I MRNA, AND HISTONE H3 ACETYLATION LEVELS AND SIGNIFICANT DECREASES IN MECP2 AND DNMT1 AND DNMT3A MRNA LEVELS. CONCLUSION: THESE FINDINGS INDICATE THAT MS INDUCED EPIGENETIC CHANGES AT THE BDNF EXON I PROMOTER AND THESE CHANGES WERE PREVENTED BY ANTIDEPRESSANT DRUG TREATMENT DURING ADULTHOOD. 2018 8 1320 32 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 9 6418 29 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 10 5703 29 SINGLE-CELL MULTIOMICS REVEAL THE SCALE OF MULTILAYERED ADAPTATIONS ENABLING CLL RELAPSE DURING VENETOCLAX THERAPY. VENETOCLAX (VEN) INHIBITS THE PROSURVIVAL PROTEIN BCL2 TO INDUCE APOPTOSIS AND IS A STANDARD THERAPY FOR CHRONIC LYMPHOCYTIC LEUKEMIA (CLL), DELIVERING HIGH COMPLETE REMISSION RATES AND PROLONGED PROGRESSION-FREE SURVIVAL IN RELAPSED CLL BUT WITH EVENTUAL LOSS OF EFFICACY. A SPECTRUM OF SUBCLONAL GENETIC CHANGES ASSOCIATED WITH VEN RESISTANCE HAS NOW BEEN DESCRIBED. TO FULLY UNDERSTAND CLINICAL RESISTANCE TO VEN, WE COMBINED SINGLE-CELL SHORT- AND LONG-READ RNA-SEQUENCING TO REVEAL THE PREVIOUSLY UNAPPRECIATED SCALE OF GENETIC AND EPIGENETIC CHANGES UNDERPINNING ACQUIRED VEN RESISTANCE. THESE APPEAR TO BE MULTILAYERED. ONE LAYER COMPRISES CHANGES IN THE BCL2 FAMILY OF APOPTOSIS REGULATORS, ESPECIALLY THE PROSURVIVAL FAMILY MEMBERS. THIS INCLUDES PREVIOUSLY DESCRIBED MUTATIONS IN BCL2 AND AMPLIFICATION OF THE MCL1 GENE BUT IS HETEROGENEOUS ACROSS AND WITHIN INDIVIDUAL PATIENT LEUKEMIAS. CHANGES IN THE PROAPOPTOTIC GENES ARE NOTABLY UNCOMMON, EXCEPT FOR SINGLE CASES WITH SUBCLONAL LOSSES OF BAX OR NOXA. MUCH MORE PROMINENT WAS UNIVERSAL MCL1 GENE UPREGULATION. THIS WAS DRIVEN BY AN OVERLYING LAYER OF EMERGENT NF-KAPPAB (NUCLEAR FACTOR KAPPA B) ACTIVATION, WHICH PERSISTED IN CIRCULATING CELLS DURING VEN THERAPY. WE DISCOVERED THAT MCL1 COULD BE A DIRECT TRANSCRIPTIONAL TARGET OF NF-KAPPAB. BOTH THE SWITCH TO ALTERNATIVE PROSURVIVAL FACTORS AND NF-KAPPAB ACTIVATION LARGELY DISSIPATE FOLLOWING VEN DISCONTINUATION. OUR STUDIES REVEAL THE EXTENT OF PLASTICITY OF CLL CELLS IN THEIR ABILITY TO EVADE VEN-INDUCED APOPTOSIS. IMPORTANTLY, THESE FINDINGS PINPOINT NEW APPROACHES TO CIRCUMVENT VEN RESISTANCE AND PROVIDE A SPECIFIC BIOLOGICAL JUSTIFICATION FOR THE STRATEGY OF VEN DISCONTINUATION ONCE A MAXIMAL RESPONSE IS ACHIEVED RATHER THAN MAINTAINING LONG-TERM SELECTIVE PRESSURE WITH THE DRUG. 2022 11 1848 40 EFFECTS OF VENLAFAXINE ON THE EXPRESSION LEVEL AND METHYLATION STATUS OF GENES INVOLVED IN OXIDATIVE STRESS IN RATS EXPOSED TO A CHRONIC MILD STRESS. RECENT HUMAN AND ANIMAL STUDIES INDICATE THAT OXIDATIVE AND NITROSATIVE STRESS MAY PLAY A ROLE IN THE AETIOLOGY AND PATHOGENESIS OF DEPRESSION. THIS STUDY INVESTIGATES THE EFFECT OF CHRONIC ADMINISTRATION OF THE SEROTONIN-NOREPINEPHRINE REUPTAKE INHIBITOR, VENLAFAXINE, ON THE EXPRESSION AND METHYLATION STATUS OF SOD1, SOD2, GPX1, GPX4, CAT, NOS1 AND NOS2 IN THE BRAIN AND BLOOD OF RATS EXPOSED TO A CHRONIC MILD STRESS (CMS) MODEL OF DEPRESSION. SEPARATE GROUPS OF ANIMALS WERE EXPOSED TO CMS FOR 2 OR 7 WEEKS; THE SECOND GROUP RECEIVED SALINE OR VENLAFAXINE (10 MG/KG/D, IP) FOR 5 WEEKS. AFTER COMPLETION OF BOTH STRESS CONDITIONS AND DRUG ADMINISTRATION, THE MRNA AND PROTEIN EXPRESSION OF SELECTED GENES AND THE METHYLATION STATUS OF THEIR PROMOTERS WERE MEASURED IN PERIPHERAL MONONUCLEAR BLOOD CELLS (PBMCS) AND IN BRAIN STRUCTURES (HIPPOCAMPUS, AMYGDALA, HYPOTHALAMUS, MIDBRAIN, CORTEX, BASAL GANGLIA) WITH THE USE OF TAQMAN GENE EXPRESSION ASSAY, WESTERN BLOT AND METHYLATION-SENSITIVE HIGH-RESOLUTION MELTING TECHNIQUES. CMS CAUSED A DECREASE IN SUCROSE CONSUMPTION, AND THIS EFFECT WAS NORMALIZED BY FLUOXETINE. IN PBMCS, SOD1, SOD2 AND NOS2 MRNA EXPRESSION CHANGED ONLY AFTER VENLAFAXINE ADMINISTRATION. IN BRAIN, CAT, GPX1, GPX4 AND NOS1 GENE EXPRESSION CHANGED FOLLOWING CMS OR VENLAFAXINE EXPOSURE, MOST PROMINENTLY IN THE HIPPOCAMPUS, MIDBRAIN AND BASAL GANGLIA. CMS INCREASED THE METHYLATION OF THE GPX1 PROMOTER IN PBMCS, THE SECOND GPX4 PROMOTER IN MIDBRAIN AND BASAL GANGLIA, AND SOD1 AND SOD2 IN HIPPOCAMPUS. THE CMS ANIMALS TREATED WITH VENLAFAXINE DISPLAYED A SIGNIFICANTLY HIGHER CAT LEVEL IN MIDBRAIN AND CEREBRAL CORTEX. CMS CAUSED AN ELEVATION OF GPX4 IN THE HIPPOCAMPUS, WHICH WAS LOWERED IN CEREBRAL CORTEX BY VENLAFAXINE. THE RESULTS INDICATE THAT CMS AND VENLAFAXINE ADMINISTRATION AFFECT THE METHYLATION OF PROMOTERS OF GENES INVOLVED IN OXIDATIVE AND NITROSATIVE STRESS. THEY ALSO INDICATE THAT PERIPHERAL AND CENTRAL TISSUE DIFFER IN THEIR RESPONSE TO STRESS OR ANTIDEPRESSANT TREATMENTS. IT IS POSSIBLE THAT THAT APART FROM DNA METHYLATION, A CRUCIAL ROLE OF EXPRESSION LEVEL OF GENES MAY BE PLAYED BY OTHER FORMS OF EPIGENETIC REGULATION, SUCH AS HISTONE MODIFICATION OR MICRORNA INTERFERENCE. THESE FINDINGS PROVIDE STRONG EVIDENCE FOR THESIS THAT ANALYSIS OF THE LEVEL OF MRNA AND PROTEIN EXPRESSION AS WELL AS THE STATUS OF PROMOTER METHYLATION CAN HELP IN UNDERSTANDING THE PATHOMECHANISMS OF MENTAL DISEASES, INCLUDING DEPRESSION, AND THE MECHANISMS OF ACTION OF DRUGS EFFECTIVE IN THEIR THERAPY. 2020 12 3372 31 HISTONE MODIFICATIONS OF THE CRHR1 GENE IN A RAT MODEL OF DEPRESSION FOLLOWING CHRONIC STRESS. MULTIPLE LINES OF EVIDENCE SUGGEST A LINK BETWEEN DEPRESSION AND CHANGES IN HYPOTHALAMIC-PITUITARY-ADRENAL (HPA)-AXIS HORMONE DYNAMICS, INCLUDING ALTERED REGULATION OF THE CORTICOTROPHIN-RELEASING HORMONE (CRH) AND ITS MAIN RECEPTOR, CORTICOTROPHIN-RELEASING HORMONE RECEPTOR 1 (CRHR1). HOWEVER, THE PRECISE MOLECULAR MECHANISMS UNDERLYING DEPRESSION REMAIN POORLY UNDERSTOOD. IN THIS STUDY, WE EMPLOYED A MODEL OF DEPRESSION IN RATS BY SUBJECTING ANIMALS TO 21 DAYS OF CHRONIC UNPREDICTABLE MILD STRESS (CUMS). REAL-TIME PCR AND WESTERN BLOTTING WERE USED TO STUDY THE MRNA AND PROTEIN EXPRESSION LEVELS OF CRHR1 IN THE HYPOTHALAMUS. IN ADDITION, CHROMATIN IMMUNOPRECIPITATION ASSAYS WERE USED TO DETECT HISTONE METHYLATION AT THE CRHR1 GENE PROMOTER; THE LEVELS OF HISTONE H3 TRIMETHYLATION AT LYSINES 4 (H3K4) AND 9 (H3K9) REFLECT ACTIVE TRANSCRIPTION AND TRANSCRIPTIONAL REPRESSION, RESPECTIVELY. RATS EXPOSED TO CUMS EXHIBITED SIGNIFICANT REDUCTION IN LOCOMOTION AND SUCROSE PREFERENCE. THESE BEHAVIORAL ALTERATIONS WERE ASSOCIATED WITH ELEVATED EXPRESSION LEVELS OF CRHR1 MRNA AND PROTEIN IN THE HYPOTHALAMUS OF RATS IN THE CUMS GROUP. WE ALSO FOUND THAT THE LEVELS OF H3K9 TRIMETHYLATION AT THE CRHR1 GENE PROMOTER IN THE CUMS GROUP WERE SIGNIFICANTLY LOWER THAN THOSE IN THE CONTROL GROUP, WHEREAS H3K4 TRIMETHYLATION LEVELS WERE THE SAME FOR BOTH GROUPS. TAKEN TOGETHER, OUR FINDINGS SUGGEST THAT THE INCREASE IN CRHR1 EXPRESSION IN THE HYPOTHALAMUS OF STRESSED RATS CORRELATES WITH A DECREASE IN THE REPRESSIVE CHROMATIN STATE CAUSED BY REDUCED H3K9 TRIMETHYLATION LEVELS. THESE DATA ARE THE FIRST IN VIVO EVIDENCE OF A ROLE FOR CHROMATIN MODIFICATIONS IN THE REGULATION OF CRHR1 GENE EXPRESSION IN THE HYPOTHALAMUS, AND MAY PROVIDE NOVEL INSIGHT INTO THERAPEUTIC APPROACHES TO TREAT DEPRESSION. 2014 13 1800 23 EFFECT OF HISTONE DEACETYLASE INHIBITOR ON ETHANOL WITHDRAWAL-INDUCED HYPERALGESIA IN RATS. BACKGROUND: INCREASED PAIN SENSITIVITY IS OBSERVED FOLLOWING ALCOHOL WITHDRAWAL, AND ATTEMPTS TO ALLEVIATE THIS HYPERALGESIA CAN CONTRIBUTE TO THE CYCLE OF ADDICTION. THE AIM OF THIS STUDY WAS TO DETERMINE IF ALCOHOL WITHDRAWAL-INDUCED HYPERALGESIA WAS OBSERVED IN A CHRONIC ETHANOL EXPOSURE MODEL AND IF THIS PAIN WAS AFFECTED BY HISTONE DEACETYLASE INHIBITORS, THUS REVEALING AN EPIGENETIC MECHANISM. METHODS: ADULT MALE SPRAGUE DAWLEY RATS RECEIVED LIEBER-DECARLI LIQUID CONTROL OR ETHANOL (9% V/V) DIET FOR 15 DAYS. MECHANICAL SENSITIVITY WAS MEASURED WITH VON FREY HAIR STIMULATION OF THE HINDPAW DURING ETHANOL ADMINISTRATION AND 24- AND 72-HOUR WITHDRAWAL. RESULTS: ETHANOL WITHDRAWAL PRODUCED SEVERE AND SUSTAINED MECHANICAL HYPERALGESIA, AN EFFECT NOT OBSERVED IN THE CONTROL OR ETHANOL-MAINTAINED GROUPS. FURTHERMORE, THIS HYPERALGESIA WAS ATTENUATED BY THE HISTONE DEACETYLASE INHIBITOR, SUBEROYLANILIDE HYDROXAMIC ACID TREATMENT. CONCLUSIONS: HEIGHTENED PAIN SENSITIVITY WAS OBSERVED FOLLOWING WITHDRAWAL FROM CHRONIC ETHANOL EXPOSURE, AND HISTONE DEACETYLASE INHIBITORS COULD BE NOVEL TREATMENTS FOR THIS ALCOHOL WITHDRAWAL-INDUCED HYPERALGESIA. 2019 14 4947 35 PATERNAL SEPSIS INDUCES ALTERATIONS OF THE SPERM METHYLOME AND DAMPENS OFFSPRING IMMUNE RESPONSES-AN ANIMAL STUDY. BACKGROUND: SEPSIS REPRESENTS THE UTMOST SEVERE CONSEQUENCE OF INFECTION, INVOLVING A DYSREGULATED AND SELF-DAMAGING IMMUNE RESPONSE OF THE HOST. WHILE DIFFERENT ENVIRONMENTAL EXPOSURES LIKE CHRONIC STRESS OR MALNUTRITION HAVE BEEN WELL DESCRIBED TO REPROGRAM THE GERMLINE AND SUBSEQUENTLY OFFSPRING ATTRIBUTES, THE INTERGENERATIONAL IMPACT OF SEPSIS AS A TREMENDOUS IMMUNOLOGICAL STRESSOR HAS NOT BEEN EXAMINED YET. METHODS: POLYMICROBIAL SEPSIS IN 12-WEEK-OLD MALE C57BL/6 MICE WAS INDUCED BY CECAL LIGATION AND PUNCTURE (CLP), FOLLOWED BY A MATING OF THE MALE SURVIVORS (OR APPROPRIATE SHAM CONTROL ANIMALS) 6 WEEKS LATER WITH HEALTHY FEMALES. ALVEOLAR MACROPHAGES OF OFFSPRING ANIMALS WERE ISOLATED AND STIMULATED WITH EITHER LPS OR ZYMOSAN, AND SUPERNATANT LEVELS OF TNF-ALPHA WERE QUANTIFIED BY ELISA. FURTHERMORE, SYSTEMIC CYTOKINE RESPONSE TO INTRAPERITONEALLY INJECTED LPS WAS ASSESSED AFTER 24 H. ALSO, MORPHOLOGY, MOTILITY, AND GLOBAL DNA METHYLATION OF THE SEPSIS SURVIVORS' SPERM WAS EXAMINED. RESULTS: COMPARATIVE REDUCED REDUCTION BISULFITE SEQUENCING (RRBS) OF SPERM REVEALED CHANGES OF DNA METHYLATION (N = 381), MOST PRONOUNCED IN THE INTERGENIC GENOME AS WELL AS WITHIN INTRONS OF DEVELOPMENTALLY RELEVANT GENES. OFFSPRING OF SEPSIS FATHERS EXHIBITED A SLIGHT DECREASE IN BODY WEIGHT, WITH A MORE PRONOUNCED WEIGHT DIFFERENCE IN MALE ANIMALS (CLP VS. SHAM). MALE DESCENDANTS OF SEPSIS FATHERS, BUT NOT FEMALE DESCENDANTS, EXHIBITED LOWER PLASMA CONCENTRATIONS OF IL-6, TNF-ALPHA, AND IL-10 24 H AFTER INJECTION OF LPS. IN LINE, ONLY ALVEOLAR MACROPHAGES OF MALE DESCENDANTS OF SEPSIS FATHERS PRODUCED LESS TNF-ALPHA UPON ZYMOSAN STIMULATION COMPARED TO SHAM DESCENDANTS, WHILE LPS RESPONSES KEPT UNCHANGED. CONCLUSION: WE CAN PROVE THAT MALE-BUT SURPRISINGLY NOT FEMALE-DESCENDANTS OF POST-SEPSIS FATHERS SHOW A DAMPENED SYSTEMIC AS WELL AS PULMONARY IMMUNE RESPONSE. BASED ON THIS OBSERVATION OF AN IMMUNE HYPO-RESPONSIVITY, WE PROPOSE THAT MALE DESCENDANTS OF SEPSIS FATHERS ARE AT RISK TO DEVELOP FUNGAL AND BACTERIAL INFECTIONS AND MIGHT BENEFIT FROM THERAPEUTIC IMMUNE MODULATION. 2018 15 3331 33 HISTONE DEACETYLASE INHIBITOR SUBERANILOHYDROXAMIC ACID TREATMENT REVERSES HYPOSENSITIVITY TO GAMMA-AMINOBUTYRIC ACID IN THE VENTRAL TEGMENTAL AREA DURING ETHANOL WITHDRAWAL. BACKGROUND: THE VENTRAL TEGMENTAL AREA (VTA) IS IMPORTANT FOR ALCOHOL-RELATED REWARD AND REINFORCEMENT. MOUSE VTA NEURONS ARE HYPOSENSITIVE TO GAMMA-AMINOBUTYRIC ACID (GABA) DURING ETHANOL (ETOH) WITHDRAWAL, AND GABA RESPONSIVENESS IS NORMALIZED BY IN VITRO TREATMENT WITH HISTONE DEACETYLASE INHIBITORS (HDACI). THE PRESENT STUDY EXAMINED THE EFFECT OF A SYSTEMICALLY ADMINISTERED HDACI, SUBERANILOHYDROXAMIC ACID (SAHA) ON GABA SENSITIVITY, AND RELATED MOLECULAR CHANGES IN VTA NEURONS DURING WITHDRAWAL AFTER CHRONIC ETOH INTAKE IN RATS. METHODS: SPRAGUE DAWLEY MALE ADULT RATS WERE FED WITH LIEBER-DECARLI DIET (9% ETOH OR CONTROL DIET) FOR 16 DAYS. EXPERIMENTAL GROUPS INCLUDED CONTROL DIET-FED AND ETOH DIET-FED (0- OR 24-HOUR WITHDRAWAL) RATS TREATED WITH EITHER SAHA OR VEHICLE INJECTION. SINGLE-UNIT RECORDINGS WERE USED TO MEASURE THE RESPONSE OF VTA NEURONS TO GABA. IMMUNOHISTOCHEMISTRY WAS PERFORMED TO EXAMINE LEVELS OF HDAC2, ACETYLATED HISTONE H3 LYSINE 9 (ACH3K9), AND GABA(A) RECEPTOR ALPHA1 AND ALPHA5 SUBUNITS IN THE VTA; QUANTITATIVE POLYMERASE CHAIN REACTION WAS PERFORMED TO EXAMINE THE MRNA LEVELS OF HDAC2 AND GABA(A) RECEPTOR SUBUNITS. RESULTS: VTA NEURONS FROM THE WITHDRAWAL GROUP EXHIBITED GABA HYPOSENSITIVITY. IN VIVO SAHA TREATMENT 2 HOURS BEFORE SACRIFICE NORMALIZED THE SENSITIVITY OF VTA NEURONS TO GABA. ETOH WITHDRAWAL WAS ASSOCIATED WITH INCREASED HDAC2 AND DECREASED ACH3K9 PROTEIN LEVELS; SAHA TREATMENT NORMALIZED ACH3K9 LEVELS. INTERESTINGLY, NO SIGNIFICANT CHANGE WAS OBSERVED IN THE MRNA LEVELS OF HDAC2. THE MRNA LEVELS, BUT NOT PROTEIN LEVELS, OF GABA(A) RECEPTOR ALPHA1 AND ALPHA5 SUBUNITS WERE INCREASED DURING WITHDRAWAL. CONCLUSIONS: WITHDRAWAL FROM CHRONIC ETOH EXPOSURE RESULTS IN A DECREASE IN GABA-MEDIATED INHIBITION, AND THIS GABA HYPOSENSITIVITY IS NORMALIZED BY IN VIVO SAHA TREATMENT. DISRUPTION OF SIGNALING IN THE VTA PRODUCED BY ALTERATION OF GABA NEUROTRANSMISSION COULD BE 1 NEUROADAPTIVE PHYSIOLOGICAL PROCESS LEADING TO CRAVING AND RELAPSE. THESE RESULTS SUGGEST THAT HDACI PHARMACOTHERAPY WITH AGENTS LIKE SAHA MIGHT BE AN EFFECTIVE TREATMENT FOR ALCOHOLISM. 2018 16 1003 24 CHRONIC TREATMENT WITH FLUOXETINE INDUCES SEX-DEPENDENT ANALGESIC EFFECTS AND MODULATES HDAC2 AND MGLU2 EXPRESSION IN FEMALE MICE. GENDER AND SEX DIFFERENCES IN PAIN RECOGNITION AND DRUG RESPONSES HAVE BEEN REPORTED IN CLINICAL TRIALS AND EXPERIMENTAL MODELS OF PAIN. AMONG ANTIDEPRESSANTS, CONTRADICTORY RESULTS HAVE BEEN OBSERVED IN PATIENTS TREATED WITH SELECTIVE SEROTONIN REUPTAKE INHIBITORS (SSRIS). THIS STUDY EVALUATED SEX DIFFERENCES IN RESPONSE TO THE SSRI FLUOXETINE AFTER CHRONIC ADMINISTRATION IN THE MOUSE FORMALIN TEST. ADULT MALE AND FEMALE CD1 MICE WERE INTRAPERITONEALLY INJECTED WITH FLUOXETINE (10 MG/KG) FOR 21 DAYS AND SUBJECTED TO PAIN ASSESSMENT. FLUOXETINE TREATMENT REDUCED THE SECOND PHASE OF THE FORMALIN TEST ONLY IN FEMALE MICE WITHOUT PRODUCING BEHAVIORAL CHANGES IN MALES. WE ALSO OBSERVED THAT FLUOXETINE WAS ABLE TO SPECIFICALLY INCREASE THE EXPRESSION OF METABOTROPIC GLUTAMATE RECEPTOR TYPE-2 (MGLU2) IN FEMALES. ALSO A REDUCED EXPRESSION OF THE EPIGENETIC MODIFYING ENZYME, HISTONE DEACETYLASE 2 (HDAC2), IN DORSAL ROOT GANGLIA (DRG) AND DORSAL HORN (DH) TOGETHER WITH AN INCREASE HISTONE 3 ACETYLATION (H3) LEVEL WAS OBSERVED IN FEMALES BUT NOT IN MALES. WITH THIS STUDY WE PROVIDE EVIDENCE THAT FLUOXETINE INDUCES SEX SPECIFIC CHANGES IN HDAC2 AND MGLU2 EXPRESSION IN THE DH OF THE SPINAL CORD AND IN DRGS AND SUGGESTS A MOLECULAR EXPLANATION FOR THE ANALGESIC EFFECTS IN FEMALE MICE. 2017 17 4579 25 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 18 6108 28 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 19 4397 37 MODULATION OF DNA METHYLATION AND GENE EXPRESSION IN RODENT CORTICAL NEUROPLASTICITY PATHWAYS EXERTS RAPID ANTIDEPRESSANT-LIKE EFFECTS. BACKGROUND: STRESS INCREASES DNA METHYLATION, PRIMARILY A SUPPRESSIVE EPIGENETIC MECHANISM CATALYZED BY DNA METHYLTRANSFERASES (DNMT), AND DECREASES THE EXPRESSION OF GENES INVOLVED IN NEURONAL PLASTICITY AND MOOD REGULATION. DESPITE CHRONIC ANTIDEPRESSANT TREATMENT DECREASES STRESS-INDUCED DNA METHYLATION, IT IS NOT KNOWN WHETHER INHIBITION OF DNMT WOULD CONVEY RAPID ANTIDEPRESSANT-LIKE EFFECTS. AIM: THIS WORK TESTED SUCH A HYPOTHESIS AND EVALUATED WHETHER A BEHAVIORAL EFFECT INDUCED BY DNMT INHIBITORS (DNMTI) CORRESPONDS WITH CHANGES IN DNA METHYLATION AND TRANSCRIPT LEVELS IN GENES CONSISTENTLY ASSOCIATED WITH THE NEUROBIOLOGY OF DEPRESSION AND SYNAPTIC PLASTICITY (BDNF, TRKB, 5-HT(1A), NMDA, AND AMPA). METHODS: MALE WISTAR RATS RECEIVED INTRAPERITONEAL (I.P.) INJECTION OF TWO PHARMACOLOGICALLY DIFFERENT DNMTI (5-AZAD 0.2 AND 0.6 MG/KG OR RG108 0.6 MG/KG) OR VEHICLE (1 ML/KG), 1 H OR 7 DAYS BEFORE THE LEARNED HELPLESSNESS TEST (LH). DNA METHYLATION IN TARGET GENES AND THE CORRESPONDENT TRANSCRIPT LEVELS WERE MEASURED IN THE HIPPOCAMPUS (HPC) AND PREFRONTAL CORTEX (PFC) USING MEDIP-QPCR. IN PARALLEL SEPARATE GROUPS, THE ANTIDEPRESSANT-LIKE EFFECT OF 5-AZAD AND RG108 WAS INVESTIGATED IN THE FORCED SWIMMING TEST (FST). THE INVOLVEMENT OF CORTICAL BDNF-TRKB-MTOR PATHWAYS WAS ASSESSED BY INTRA-VENTRAL MEDIAL PFC (VMPFC) INJECTIONS OF RAPAMYCIN (MTOR INHIBITOR), K252A (TRKB RECEPTOR ANTAGONIST), OR VEHICLE (0.2 MUL/SIDE). RESULTS: WE FOUND THAT BOTH 5-AZAD AND RG108 ACUTELY AND 7 DAYS BEFORE THE TEST DECREASED ESCAPE FAILURES IN THE LH. LH STRESS INCREASED DNA METHYLATION AND DECREASED TRANSCRIPT LEVELS OF BDNF IV AND TRKB IN THE PFC, EFFECTS THAT WERE NOT SIGNIFICANTLY ATTENUATED BY RG108 TREATMENT. THE SYSTEMIC ADMINISTRATION OF 5-AZAD (0.2 MG/KG) AND RG108 (0.2 MG/KG) INDUCED AN ANTIDEPRESSANT-LIKE EFFECT IN FST, WHICH WAS, HOWEVER, ATTENUATED BY TRKB AND MTOR INHIBITION INTO THE VMPFC. CONCLUSION: THESE FINDINGS SUGGEST THAT ACUTE INHIBITION OF STRESS-INDUCED DNA METHYLATION PROMOTES RAPID AND SUSTAINED ANTIDEPRESSANT EFFECTS ASSOCIATED WITH INCREASED BDNF-TRKB-MTOR SIGNALING IN THE PFC. 2021 20 2353 30 EPIGENETIC REGULATION OF OPIOID-INDUCED HYPERALGESIA, DEPENDENCE, AND TOLERANCE IN MICE. REPEATED ADMINISTRATION OF OPIOIDS SUCH AS MORPHINE INDUCES PERSISTENT BEHAVIORAL CHANGES INCLUDING OPIOID-INDUCED HYPERALGESIA (OIH), TOLERANCE, AND PHYSICAL DEPENDENCE. IN THE CURRENT WORK WE EXPLORED HOW THE BALANCE OF HISTONE ACETYLTRANSFERASE (HAT) VERSUS HISTONE DEACETYLASE (HDAC) MIGHT REGULATE THESE MORPHINE-INDUCED CHANGES. NOCICEPTIVE THRESHOLDS, ANALGESIA, AND PHYSICAL DEPENDENCE WERE ASSESSED DURING AND FOR A PERIOD OF SEVERAL WEEKS AFTER MORPHINE EXPOSURE. TO PROBE THE ROLES OF HISTONE ACETYLATION, THE HAT INHIBITOR CURCUMIN OR A SELECTIVE HDAC INHIBITOR SUBEROYLANILIDE HYDROXAMIC ACID (SAHA) WAS ADMINISTERED DAILY TO GROUPS OF ANIMALS. HISTONE ACETYLATION IN SPINAL CORD WAS ASSESSED BY WESTERN BLOT AND IMMUNOHISTOCHEMISTRY. CONCURRENT ADMINISTRATION OF CURCUMIN WITH MORPHINE FOR 4 DAYS SIGNIFICANTLY REDUCED DEVELOPMENT OF OPIOID-INDUCED MECHANICAL ALLODYNIA, THERMAL HYPERALGESIA, TOLERANCE, AND PHYSICAL DEPENDENCE. CONVERSELY, THE HDAC INHIBITOR SAHA ENHANCED THESE RESPONSES. INTERESTINGLY, SAHA TREATMENT AFTER THE TERMINATION OF OPIOID ADMINISTRATION SUSTAINED THESE BEHAVIORAL CHANGES FOR AT LEAST 4 WEEKS. HISTONE H3 ACETYLATION IN THE DORSAL HORN OF THE SPINAL CORD WAS INCREASED AFTER CHRONIC MORPHINE TREATMENT, BUT H4 ACETYLATION WAS UNCHANGED. MOREOVER, WE OBSERVED A DECREASE IN HDAC ACTIVITY IN THE SPINAL CORDS OF MORPHINE-TREATED MICE WHILE OVERALL HAT ACTIVITY WAS UNCHANGED, SUGGESTING A SHIFT TOWARD A STATE OF ENHANCED HISTONE ACETYLATION. PERSPECTIVE: THE CURRENT STUDY INDICATES THAT EPIGENETIC MECHANISMS PLAY A CRUCIAL ROLE IN OPIOID-INDUCED LONG-LASTING NEUROPLASTICITY. THESE RESULTS PROVIDE NEW SIGHT INTO UNDERSTANDING THE MECHANISMS OF OPIOID-INDUCED NEUROPLASTICITY AND SUGGEST NEW STRATEGIES TO LIMIT OPIOID ABUSE POTENTIAL AND INCREASE THE VALUE OF THESE DRUGS AS ANALGESICS. 2013