1 772 101 CDYL DEFICIENCY BRAKES NEURONAL EXCITABILITY AND NOCICEPTION THROUGH PROMOTING KCNB1 TRANSCRIPTION IN PERIPHERAL SENSORY NEURONS. EPIGENETIC MODIFICATIONS ARE INVOLVED IN THE ONSET, DEVELOPMENT, AND MAINTENANCE OF PAIN; HOWEVER, THE PRECISE EPIGENETIC MECHANISM UNDERLYING PAIN REGULATION REMAINS ELUSIVE. HERE IT IS REPORTED THAT THE EPIGENETIC FACTOR CHROMODOMAIN Y-LIKE (CDYL) IS CRUCIAL FOR PAIN PROCESSING. SELECTIVE KNOCKOUT OF CDYL IN SENSORY NEURONS RESULTS IN DECREASED NEURONAL EXCITABILITY AND NOCICEPTION. MOREOVER, CDYL FACILITATES HISTONE 3 LYSINE 27 TRIMETHYLATION (H3K27ME3) DEPOSITION AT THE KCNB1 INTRON REGION THUS SILENCING VOLTAGE-GATED POTASSIUM CHANNEL (K(V) ) SUBFAMILY MEMBER K(V) 2.1 TRANSCRIPTION. LOSS FUNCTION OF CDYL ENHANCES TOTAL K(V) AND K(V) 2.1 CURRENT DENSITY IN DORSAL ROOT GANGLIA AND KNOCKDOWN OF K(V) 2.1 REVERSES THE PAIN-RELATED PHENOTYPES OF CDYL DEFICIENCY MICE. FURTHERMORE, FOCAL ADMINISTRATION OF A NOVEL POTENT CDYL ANTAGONIST BLUNTS NOCICEPTION AND ATTENUATES NEUROPATHIC PAIN. THESE FINDINGS REVEAL THAT CDYL IS A CRITICAL REGULATOR OF PAIN SENSATION AND SHED LIGHT ON THE DEVELOPMENT OF NOVEL ANALGESICS TARGETING EPIGENETIC MECHANISMS. 2022 2 4944 17 PATERNAL PRECONCEPTION ETHANOL EXPOSURE BLUNTS HYPOTHALAMIC-PITUITARY-ADRENAL AXIS RESPONSIVITY AND STRESS-INDUCED EXCESSIVE FLUID INTAKE IN MALE MICE. A GROWING NUMBER OF ENVIRONMENTAL INSULTS HAVE BEEN SHOWN TO INDUCE EPIGENETIC EFFECTS THAT PERSIST ACROSS GENERATIONS. FOR INSTANCE, PATERNAL PRECONCEPTION EXPOSURES TO ETHANOL OR STRESS HAVE INDEPENDENTLY BEEN SHOWN TO EXERT SUCH INTERGENERATIONAL EFFECTS. SINCE ETHANOL EXPOSURE IS A PHYSIOLOGICAL STRESSOR THAT ACTIVATES THE HYPOTHALAMIC-PITUITARY-ADRENAL (HPA) AXIS, WE HYPOTHESIZED THAT PATERNAL ETHANOL EXPOSURE WOULD IMPACT STRESS RESPONSIVITY OF OFFSPRING. ADULT MALE MICE WERE EXPOSED TO CHRONIC INTERMITTENT VAPOR ETHANOL OR CONTROL CONDITIONS FOR 5 WEEKS BEFORE BEING MATED WITH ETHANOL-NAIVE FEMALES TO PRODUCE ETHANOL (E)- AND CONTROL (C)-SIRED OFFSPRING. ADULT MALE AND FEMALE OFFSPRING WERE TESTED FOR PLASMA CORTICOSTERONE (CORT) LEVELS FOLLOWING ACUTE RESTRAINT STRESS AND THE MALE OFFSPRING WERE FURTHER EXAMINED FOR STRESS-EVOKED 2-BOTTLE CHOICE ETHANOL-DRINKING. PATERNAL ETHANOL EXPOSURE BLUNTED PLASMA CORT LEVELS FOLLOWING ACUTE RESTRAINT STRESS SELECTIVELY IN MALE OFFSPRING; FEMALES WERE UNAFFECTED. IN A STRESS-EVOKED ETHANOL-DRINKING ASSAY, THERE WAS NO EFFECT OF STRESS ON ETHANOL CONSUMPTION. HOWEVER, C-SIRED MALES EXHIBITED INCREASED TOTAL FLUID INTAKE (POLYDIPSIA) IN RESPONSE TO STRESS WHILE E-SIRED MALES WERE RESISTANT TO THIS STRESS-INDUCED PHENOTYPE. TAKEN TOGETHER, THESE DATA SUGGEST THAT PATERNAL ETHANOL EXPOSURE IMPARTS STRESS HYPORESPONSIVITY TO MALE OFFSPRING. 2016 3 1714 17 DYSLEXIA AS AN ADAPTATION TO CORTICO-LIMBIC STRESS SYSTEM REACTIVITY. A NEW SCHOOL OF THOUGHT IN EVOLUTIONARY DEVELOPMENTAL BIOLOGY, COMBINED WITH RESEARCH IN THE NEUROBIOLOGY OF STRESS, SUGGEST THAT EARLY EXPOSURE TO STRESSFUL CIRCUMSTANCES MAY BE A CAUSE OF DYSLEXIA. A BALANCE BETWEEN EPIGENETIC, STRESS-INDUCED AND COGNITIVE-GROWTH GENETIC PROGRAMS MODULATES THE BRAIN'S CELLULAR, REGIONAL, AND NETWORK HOMEOSTASIS. THIS BALANCE IS ESSENTIAL FOR ADAPTABILITY TO THE NORMATIVE RANGE OF EVERYDAY STRESS. HOWEVER, EVEN MILD CHRONIC STRESS EXPOSITION MAY OVERACTIVATE THE HYPOTHALMIC-PITUITARY-ADRENAL STRESS AXIS, UPSETTING THE HOMEOSTATIC BALANCE BETWEEN THESE PROGRAMS, AND EXPOSING THE BRAIN TO HARMFUL LEVELS OF STRESS HORMONES. A PROTECTIVE STRATEGY TO SUSTAINED DISEQUILIBRIUM PRECOCIOUSLY ADVANCES MATURATION AT THE COST OF NEUROPLASTICITY, WHICH BLUNTS STRESS AXIS REACTIVITY BUT ALSO COMPROMISES LEARNING POTENTIAL IN THE PREFRONTAL CORTEX AND NETWORKS ASSOCIATED WITH DYSLEXIA. STRESS EXCEEDING AN INDIVIDUAL'S RANGE OF RESILIENCE: (1) REDUCES LEVELS OF TFEB AND BDNF, GENE REGULATORY FACTORS PROLONGING MATURATION AND NEUROPLASTICITY; (2) INTERFERES WITH THE INSULAR CORTEX, AMYGDALA AND HIPPOCAMPUS IN COORDINATING AFFERENT VISCERAL SIGNALS WITH COGNITIVE PERFORMANCE; (3) OVER-RECRUITS THE BRAIN'S DEFAULT MODE NETWORK; AND (4) AMPLIFIES RELEASE FROM THE LOCUS COERULEUS/NOREPINEPHRINE SYSTEM WHICH IMPAIRS THE ENTRAINMENT OF OSCILLATIONS IN THE LOWER PHONOLOGICAL FREQUENCIES OF SPEECH. EVIDENCE SUPPORTING A STRESS-GROWTH IMBALANCE IS PRELIMINARY, BUT HOLDS PROMISE FOR RECONCEPTUALIZING THE NEUROBIOLOGY OF DYSLEXIA AND REDUCING ITS PREVALENCE. 2020 4 863 32 CHROMODOMAIN Y-LIKE PROTEIN-MEDIATED HISTONE CROTONYLATION REGULATES STRESS-INDUCED DEPRESSIVE BEHAVIORS. BACKGROUND: MAJOR DEPRESSIVE DISORDER IS A PREVALENT AND LIFE-THREATENING ILLNESS IN MODERN SOCIETY. THE SUSCEPTIBILITY TO MAJOR DEPRESSIVE DISORDER IS PROFOUNDLY INFLUENCED BY ENVIRONMENTAL FACTORS, SUCH AS STRESSFUL LIFESTYLE OR TRAUMATIC EVENTS, WHICH COULD IMPOSE MALADAPTIVE TRANSCRIPTIONAL PROGRAM THROUGH EPIGENETIC REGULATION. HOWEVER, THE UNDERLYING MOLECULAR MECHANISMS REMAIN ELUSIVE. HERE, WE EXAMINED THE ROLE OF HISTONE CROTONYLATION, A NOVEL TYPE OF HISTONE MODIFICATION, AND CHROMODOMAIN Y-LIKE PROTEIN (CDYL), A CROTONYL-COENZYME A HYDRATASE AND HISTONE METHYLLYSINE READER, IN THIS PROCESS. METHODS: WE USED CHRONIC SOCIAL DEFEAT STRESS AND MICRODEFEAT STRESS TO EXAMINE THE DEPRESSIVE BEHAVIORS. IN ADDITION, WE COMBINED PROCEDURES THAT DIAGNOSE BEHAVIORAL STRATEGY IN MALE MICE WITH HISTONE EXTRACTION, VIRAL-MEDIATED CDYL MANIPULATIONS, RNA SEQUENCING, CHROMATIN IMMUNOPRECIPITATION, WESTERN BLOT, AND MESSENGER RNA QUANTIFICATION. RESULTS: THE RESULTS INDICATE THAT STRESS-SUSCEPTIBLE RODENTS EXHIBIT LOWER LEVELS OF HISTONE CROTONYLATION IN THE MEDIAL PREFRONTAL CORTEX CONCURRENT WITH SELECTIVE UPREGULATION OF CDYL. OVEREXPRESSION OF CDYL IN THE PRELIMBIC CORTEX, A SUBREGION OF THE MEDIAL PREFRONTAL CORTEX, INCREASES MICRODEFEAT-INDUCED SOCIAL AVOIDANCE BEHAVIORS AND ANHEDONIA IN MICE. CONVERSELY, KNOCKDOWN OF CDYL IN THE PRELIMBIC CORTEX PREVENTS CHRONIC SOCIAL DEFEAT STRESS-INDUCED DEPRESSION-LIKE BEHAVIORS. MECHANISTICALLY, WE SHOW THAT CDYL INHIBITS STRUCTURAL SYNAPTIC PLASTICITY MAINLY BY TRANSCRIPTIONAL REPRESSION OF NEUROPEPTIDE VGF NERVE GROWTH FACTOR INDUCIBLE, AND THIS ACTIVITY IS DEPENDENT ON ITS DUAL EFFECT ON HISTONE CROTONYLATION AND H3K27 TRIMETHYLATION ON THE VGF PROMOTER. CONCLUSIONS: OUR RESULTS DEMONSTRATE THAT CDYL-MEDIATED HISTONE CROTONYLATION PLAYS A CRITICAL ROLE IN REGULATING STRESS-INDUCED DEPRESSION, PROVIDING A POTENTIAL THERAPEUTIC TARGET FOR MAJOR DEPRESSIVE DISORDER. 2019 5 4943 19 PATERNAL PRECONCEPTION ALCOHOL EXPOSURE IMPARTS INTERGENERATIONAL ALCOHOL-RELATED BEHAVIORS TO MALE OFFSPRING ON A PURE C57BL/6J BACKGROUND. WHILE ALCOHOL USE DISORDER (AUD) IS A HIGHLY HERITABLE CONDITION, THE BASIS OF AUD IN FAMILIES WITH A HISTORY OF ALCOHOLISM IS DIFFICULT TO EXPLAIN BY GENETIC VARIATION ALONE. EMERGING EVIDENCE SUGGESTS THAT PARENTAL EXPERIENCE PRIOR TO CONCEPTION CAN AFFECT INHERITANCE OF COMPLEX BEHAVIORS IN OFFSPRING VIA NON-GENOMIC (EPIGENETIC) MECHANISMS. FOR INSTANCE, MALE C57BL/6J (B6) MICE EXPOSED TO CHRONIC INTERMITTENT VAPOR ETHANOL (CIE) PRIOR TO MATING WITH STRAIN 129S1/SVIMJ ETHANOL-NAIVE FEMALES PRODUCE MALE OFFSPRING WITH REDUCED ETHANOL-DRINKING PREFERENCE, INCREASED ETHANOL SENSITIVITY, AND INCREASED BRAIN-DERIVED NEUROTROPHIC FACTOR (BDNF) EXPRESSION IN THE VENTRAL TEGMENTAL AREA (VTA). IN THE PRESENT STUDY, WE TESTED THE HYPOTHESIS THAT THESE INTERGENERATIONAL EFFECTS OF PATERNAL CIE ARE REPRODUCIBLE IN MALE OFFSPRING ON AN INBRED B6 BACKGROUND. TO THIS END, B6 MALES WERE EXPOSED TO 6 WEEKS OF CIE (OR ROOM AIR AS A CONTROL) BEFORE MATING WITH ETHANOL-NAIVE B6 FEMALES TO PRODUCE ETHANOL (E)-SIRED AND CONTROL (C)-SIRED MALE AND FEMALE OFFSPRING. WE OBSERVED A SEX-SPECIFIC EFFECT, AS E-SIRED MALES EXHIBITED DECREASED TWO-BOTTLE FREE-CHOICE ETHANOL-DRINKING PREFERENCE, INCREASED SENSITIVITY TO THE ANXIOLYTIC EFFECTS OF ETHANOL, AND INCREASED VTA BDNF EXPRESSION; NO DIFFERENCES WERE OBSERVED IN FEMALE OFFSPRING. THESE FINDINGS CONFIRM AND EXTEND OUR PREVIOUS RESULTS BY DEMONSTRATING THAT THE EFFECTS OF PATERNAL PRECONCEPTION ETHANOL ARE REPRODUCIBLE USING GENETICALLY IDENTICAL, INBRED B6 ANIMALS. 2017 6 69 30 A MEDIAL PREFRONTAL CORTEX-NUCLEUS ACUMENS CORTICOTROPIN-RELEASING FACTOR CIRCUITRY FOR NEUROPATHIC PAIN-INCREASED SUSCEPTIBILITY TO OPIOID REWARD. RECENT STUDIES HAVE SHOWN THAT PERSISTENT PAIN FACILITATES THE RESPONSE TO MORPHINE REWARD. HOWEVER, THE CIRCUIT MECHANISM UNDERLYING THIS PROCESS REMAINS AMBIGUOUS. IN THIS STUDY, USING CHRONIC CONSTRICTION INJURY (CCI) OF THE SCIATIC NERVE IN MICE, WE FOUND THAT PERSISTENT NEUROPATHIC PAIN REDUCED THE MINIMUM NUMBER OF MORPHINE CONDITIONING SESSIONS REQUIRED TO INDUCE CONDITIONED PLACE PREFERENCE (CPP) BEHAVIOR. THIS DOSE OF MORPHINE HAD NO EFFECT ON THE PAIN THRESHOLD. IN THE MEDIAL PREFRONTAL CORTEX (MPFC), WHICH IS INVOLVED IN BOTH PAIN AND EMOTION PROCESSING, CORTICOTROPIN-RELEASING FACTOR (CRF) EXPRESSING NEURONAL ACTIVITY WAS INCREASED IN CCI MICE. CHEMOGENETIC INHIBITION OF MPFC CRF NEURONS REVERSED CCI-INDUCED MORPHINE CPP FACILITATION. FURTHERMORE, THE NUCLEUS ACUMENS (NAC) RECEIVED MPFC CRF FUNCTIONAL PROJECTIONS THAT EXERTED EXCITATORY EFFECTS ON NAC NEURONS. OPTOGENETIC INHIBITION OF MPCF NEURONAL TERMINALS OR LOCAL INFUSION OF THE CRF RECEPTOR 1 (CRFR1) ANTAGONIST IN THE NAC RESTORED THE EFFECTS OF NEUROPATHIC PAIN ON MORPHINE-INDUCED CPP BEHAVIOR, BUT NOT IN NORMAL MICE. ON A MOLECULAR LEVEL, IN CCI MICE, CRFR1 PROTEIN EXPRESSION WAS INCREASED IN THE NAC BY A HISTONE DIMETHYLTRANSFERASE G9A-MEDIATED EPIGENETIC MECHANISM. LOCAL G9A KNOCKDOWN INCREASED THE EXPRESSION OF CRFR1 AND MIMICKED CCI-INDUCED HYPERSENSITIVITY TO ACQUIRING MORPHINE CPP. TAKEN TOGETHER, THESE FINDINGS DEMONSTRATE A PREVIOUSLY UNKNOWN AND SPECIFIC MPFC CRF ENGAGEMENT OF NAC NEURONAL CIRCUITS, THE SENSITIZATION OF WHICH FACILITATES BEHAVIORAL RESPONSES TO MORPHINE REWARD IN NEUROPATHIC PAIN STATES VIA CRFR1S. 2018 7 6551 24 TRANSGENERATIONAL BLUNTING OF MORPHINE-INDUCED CORTICOSTERONE SECRETION IS ASSOCIATED WITH DYSREGULATED GENE EXPRESSION IN MALE OFFSPRING. A NUMBER OF PARENTAL EXPERIENCES, EVEN WHEN OCCURRING PRIOR TO CONCEPTION, HAVE BEEN SHOWN TO INDUCE TRANSGENERATIONAL EFFECTS BEYOND THE FIRST GENERATION. IN THE CASE OF EXPOSURE TO DRUGS OF ABUSE, STUDIES IN RODENTS SUGGEST THAT OFFSPRING DEMONSTRATE SIGNIFICANT DIFFERENCES IN HOW THEY RESPOND TO THE DRUG TO WHICH THEIR PARENT WAS EXPOSED. WE HAVE PREVIOUSLY OBSERVED SIGNIFICANT ALTERATIONS IN MORPHINE ANALGESIA, CONDITIONED PLACE PREFERENCE AND SELF-ADMINISTRATION IN THE OFFSPRING OF FEMALES EXPOSED TO MORPHINE DURING ADOLESCENT DEVELOPMENT. IN ADDITION TO EFFECTS ON PAIN PERCEPTION AND REWARD, MORPHINE ALSO MODULATES THE HYPOTHALAMIC PITUITARY ADRENAL (HPA) AXIS. THE PURPOSE OF THE CURRENT STUDY WAS TO DETERMINE WHETHER FEMALE ADOLESCENT MORPHINE EXPOSURE RESULTS IN TRANSGENERATIONAL EFFECTS ON REGULATION OF THE HPA AXIS BY MORPHINE IN FUTURE GENERATIONS. ADOLESCENT MORPHINE WAS ADMINISTERED TO FEMALE SPRAGUE DAWLEY RATS USING A 10 DAY, ESCALATING DOSE REGIMEN OF MORPHINE (5-25 MG/KG; FROM 30 TO 39 DAYS OF AGE). CONTROL ANIMALS RECEIVED SALINE. BOTH SALINE AND MORPHINE EXPOSED FEMALES (SAL-F0 AND MOR-F0, RESPECTIVELY) WERE MATED WITH DRUG NAIVE MALES BEGINNING AT LEAST 3 WEEKS AFTER THE FINAL INJECTION. PLASMA CORTICOSTERONE LEVELS WERE MEASURED IN MALE AND FEMALE OFFSPRING (F1) DURING ADULTHOOD FOLLOWING 0, 0.1, OR 10 MG/KG MORPHINE. IN ADDITION, EXPRESSION OF CORTICOTROPIN RELEASING HORMONE (CRH) AND MU OPIOID RECEPTOR (OPRM1) IN THE PARAVENTRICULAR NUCLEUS (PVN) WERE MEASURED USING QUANTITATIVE PCR. MOR-F1 MALES, BUT NOT FEMALES, HAD BLUNTED MORPHINE-INDUCED CORTICOSTERONE SECRETION. THIS EFFECT WAS SPECIFIC TO OFFSPRING FROM FEMALES EXPOSED TO MORPHINE DURING ADOLESCENCE AS THOSE EXPOSED DURING ADULTHOOD PRODUCED OFFSPRING IN WHICH THE EFFECT WAS ABSENT. IN ADDITION, MOR-F1 MALES HAD SIGNIFICANTLY LOWER LEVELS OF PVN CRH FOLLOWING SALINE. THESE EFFECTS WERE NOT DRIVEN BY PVN OPRM1 IN THE F1 MALES AS THERE WERE NO DIFFERENCES BASED ON MATERNAL ADOLESCENT EXPOSURE. TO DETERMINE THE PERSISTENCE OF THE BLUNTED MORPHINE-INDUCED CORTICOSTERONE EFFECT, SAL-F2 AND MOR-F2 MALES WERE EXAMINED. BLUNTED MORPHINE-INDUCED CORTICOSTERONE SECRETION EXTENDED INTO THE MOR-F2 GENERATION, AS WELL AS EFFECTS ON CRH. IN ADDITION, THERE WAS ADDITIONAL DYSREGULATION OFOPRM1 EXPRESSION IN THE PVN IN MOR-F2 COMPARED WITH SAL-F2 MALES. THESE FINDINGS SUGGEST THAT SEX-SPECIFIC ALTERATIONS IN OPIOID-MEDIATED REGULATION OF THE HPA AXIS ARE TRANSGENERATIONALLY TRANSMITTED FOR AT LEAST TWO GENERATIONS FOLLOWING FEMALE ADOLESCENT MORPHINE EXPOSURE. THESE EFFECTS MAY PLAY A ROLE IN THE PREVIOUSLY OBSERVED CHANGES IN MORPHINE ANALGESIA AND REWARD-RELATED BEHAVIORS OBSERVED IN THIS PHENOTYPE. IN ADDITION, ALTERATIONS IN HPA FUNCTIONING SUCH AS THESE MAY PLAY A BROAD ROLE IN TRANSGENERATIONAL EPIGENETIC TRANSMISSION. 2018 8 1005 22 CHRONIC VARIABLE PHYSICAL STRESS DURING THE PERIPUBERTAL-JUVENILE PERIOD CAUSES DIFFERENTIAL DEPRESSIVE AND ANXIOGENIC EFFECTS IN THE NOVELTY-SEEKING PHENOTYPE: FUNCTIONAL IMPLICATIONS FOR HIPPOCAMPAL AND AMYGDALAR BRAIN-DERIVED NEUROTROPHIC FACTOR AND THE MOSSY FIBRE PLASTICITY. EXPERIMENTALLY NAIVE RATS SHOW VARIANCE IN THEIR LOCOMOTOR REACTIVITY TO NOVELTY, SOME DISPLAYING HIGHER (HR) WHILE OTHERS DISPLAYING LOWER (LR) REACTIVITY, ASSOCIATED WITH VULNERABILITY TO STRESS. WE EMPLOYED A CHRONIC VARIABLE PHYSICAL STRESS REGIMEN INCORPORATING INTERMITTENT AND RANDOM EXPOSURES OF PHYSICAL STRESSORS OR CONTROL HANDLING DURING THE PERIPUBERTAL-JUVENILE PERIOD TO ASSESS INTERACTIONS BETWEEN STRESS AND THE LRHR PHENOTYPE IN DEPRESSIVE- AND ANXIETY-LIKE BEHAVIORS ON THE FORCED SWIM AND SOCIAL INTERACTION TESTS, RESPECTIVELY. A DECREASE IN IMMOBILITY IN THE FORCED SWIM TEST ALONG WITH A DECREASE IN SOCIAL CONTACT IN THE SOCIAL INTERACTION TEST WERE OBSERVED IN THE JUVENILE HRS, COUPLED WITH INCREASES IN BRAIN-DERIVED NEUROTROPHIC FACTOR (BDNF) MRNA IN THE HIPPOCAMPUS AND IN THE BASOLATERAL AMYGDALA WITH CHRONIC VARIABLE PHYSICAL STRESS. IN CONTRAST, AN INCREASE IN IMMOBILITY IN THE FORCED SWIM TEST AND A DECREASE IN SOCIAL CONTACT WAS OBSERVED IN THE LR COUNTERPARTS COUPLED WITH AN INCREASE IN THE BDNF MRNA IN THE BASOLATERAL AMYGDALA FOLLOWING CHRONIC VARIABLE PHYSICAL STRESS. FURTHERMORE, CHRONIC PHYSICAL STRESS LED TO INCREASED H3 AND H4 ACETYLATION AT THE P2 AND P4 PROMOTERS OF THE HIPPOCAMPAL BDNF GENE IN THE HR RATS THAT IS ASSOCIATED WITH INCREASED SUPRAPYRAMIDAL MOSSY FIBRE (SP-MF) TERMINAL FIELD VOLUME. IN CONTRAST, CHRONIC VARIABLE PHYSICAL STRESS LED TO DECREASED H4 ACETYLATION AT THE P4 PROMOTER, ASSOCIATED WITH DECREASED SP-MF VOLUME IN THE LR RATS. THESE FINDINGS SHOW DISSOCIATION IN DEPRESSIVE- AND ANXIETY-LIKE BEHAVIORS FOLLOWING CHRONIC VARIABLE PHYSICAL STRESS IN THE JUVENILE HR ANIMALS THAT MAY BE MEDIATED BY INCREASED LEVELS OF BDNF IN THE HIPPOCAMPUS AND IN THE AMYGDALA, RESPECTIVELY. MOREOVER, CHRONIC VARIABLE PHYSICAL STRESS DURING THE PERIPUBERTAL-JUVENILE PERIOD RESULTS IN OPPOSITE EFFECTS IN DEPRESSIVE-LIKE BEHAVIOR IN THE LRHR RATS BY WAY OF INDUCING DIFFERENTIAL EPIGENETIC REGULATION OF THE HIPPOCAMPAL BDNF GENE THAT, IN TURN, MAY MEDIATE MOSSY FIBRE SPROUTING. 2011 9 1740 22 EARLY ENRICHED ENVIRONMENT PREVENTS EPIGENETIC P11 GENE CHANGES INDUCED BY ADULTHOOD STRESS IN MICE. POSITIVE EXPERIENCES IN EARLY LIFE MAY IMPROVE THE CAPACITY TO COPE WITH ADULTHOOD STRESS THROUGH EPIGENETIC MODIFICATION. WE INVESTIGATED WHETHER AN ENRICHED ENVIRONMENT (EE) IN THE POSTNATAL PERIOD AFFECTED EPIGENETIC CHANGES IN THE P11 GENE INDUCED BY CHRONIC UNPREDICTABLE STRESS (CUS) IN ADULT C57BL/6J MICE. EE WAS INTRODUCED FOR 5 WEEKS DURING POSTNATAL DAYS 21-55. AFTER EE, THE MICE WERE SUBJECTED TO CUS FOR 4 WEEKS. EE PREVENTED DEPRESSION-LIKE BEHAVIOR INDUCED BY ADULT CUS. EE PREVENTED A DECREASE IN P11 MRNA AND HISTONE H3 ACETYLATION INDUCED BY CUS, WITH CHANGES IN THE EXPRESSION OF HISTONE DEACETYLASE 5. MOREOVER, EE PREVENTED CHANGES IN TRIMETHYLATION OF HISTONE H3 LYSINE 4 (H3K4) AND H3K27 INDUCED BY CUS. FURTHERMORE, EE HAD POSITIVE EFFECTS ON BEHAVIOR AND EPIGENETIC ALTERATIONS IN ADULT MICE WITHOUT CUS. THESE RESULTS SUGGEST THAT ONE OF THE UNDERLYING MECHANISMS OF EARLY-LIFE EE MAY INVOLVE EPIGENETIC MODIFICATION OF THE HIPPOCAMPAL P11 GENE PROMOTER. 2021 10 581 19 BEHAVIORAL AND NEUROCHEMICAL CHARACTERIZATION OF TRKB-DEPENDENT MECHANISMS OF AGOMELATINE IN GLUCOCORTICOID RECEPTOR-IMPAIRED MICE. GROWING EVIDENCE INDICATES THAT IMPAIRMENT OF THE STRESS RESPONSE, IN PARTICULAR THE NEGATIVE FEEDBACK REGULATION MECHANISM EXERTED BY THE HYPOTHALAMO-PITUITARY-ADRENAL (HPA) AXIS, MIGHT BE RESPONSIBLE FOR THE HIPPOCAMPAL ATROPHY OBSERVED IN DEPRESSED PATIENTS. ANTIDEPRESSANTS, POSSIBLY THROUGH THE ACTIVATION OF BDNF SIGNALING, MAY ENHANCE NEUROPLASTICITY AND RESTORE NORMAL HIPPOCAMPAL FUNCTIONS. IN THIS CONTEXT, GLUCOCORTICOID RECEPTOR-IMPAIRED (GR-I) MICE-A TRANSGENIC MOUSE MODEL OF REDUCED GR-INDUCED NEGATIVE FEEDBACK REGULATION OF THE HPA AXIS-WERE USED TO INVESTIGATE THE ROLE OF BDNF/TRKB SIGNALING IN THE BEHAVIORAL AND NEUROCHEMICAL EFFECTS OF THE NEW GENERATION ANTIDEPRESSANT DRUG, AGOMELATINE. GR-I MICE EXHIBITED MARKED ALTERATIONS IN DEPRESSIVE-LIKE AND ANXIETY-LIKE BEHAVIORS, TOGETHER WITH A DECREASED CELL PROLIFERATION AND ALTERED LEVELS OF NEUROPLASTIC AND EPIGENETIC MARKERS IN THE HIPPOCAMPUS. GR-I MICE AND THEIR WILD-TYPE LITTERMATES WERE TREATED FOR 21 DAYS WITH VEHICLE, AGOMELATINE (50MG/KG/DAY; I.P) OR THE TRKB INHIBITOR ANA-12 (0.5MG/KG/DAY, I.P) ALONE, OR IN COMBINATION WITH AGOMELATINE. CHRONIC TREATMENT WITH AGOMELATINE RESULTED IN ANTIDEPRESSANT-LIKE EFFECTS IN GR-I MICE AND REVERSED THE DEFICIT IN HIPPOCAMPAL CELL PROLIFERATION AND SOME OF THE ALTERATIONS OF MRNA PLASTICITY MARKERS IN GR-I MICE. ANA-12 BLOCKED THE EFFECT OF AGOMELATINE ON MOTOR ACTIVITY AS WELL AS ITS ABILITY TO RESTORE A NORMAL HIPPOCAMPAL CELL PROLIFERATION AND EXPRESSION OF NEUROTROPHIC FACTORS. ALTOGETHER, OUR FINDINGS INDICATE THAT AGOMELATINE REQUIRES TRKB SIGNALING TO REVERSE SOME OF THE MOLECULAR AND BEHAVIORAL ALTERATIONS CAUSED BY HPA AXIS IMPAIRMENT. 2016 11 4222 18 METHYLATION AT THE CPG ISLAND SHORE REGION UPREGULATES NR3C1 PROMOTER ACTIVITY AFTER EARLY-LIFE STRESS. EARLY-LIFE STRESS (ELS) INDUCES LONG-LASTING CHANGES IN GENE EXPRESSION CONFERRING AN INCREASED RISK FOR THE DEVELOPMENT OF STRESS-RELATED MENTAL DISORDERS. GLUCOCORTICOID RECEPTORS (GR) MEDIATE THE NEGATIVE FEEDBACK ACTIONS OF GLUCOCORTICOIDS (GC) IN THE PARAVENTRICULAR NUCLEUS (PVN) OF THE HYPOTHALAMUS AND ANTERIOR PITUITARY AND THEREFORE PLAY A KEY ROLE IN THE REGULATION OF THE HYPOTHALAMIC-PITUITARY-ADRENAL (HPA) AXIS AND THE ENDOCRINE RESPONSE TO STRESS. WE HERE SHOW THAT ELS PROGRAMS THE EXPRESSION OF THE GR GENE (NR3C1) BY SITE-SPECIFIC HYPERMETHYLATION AT THE CPG ISLAND (CGI) SHORE IN HYPOTHALAMIC NEURONS THAT PRODUCE CORTICOTROPIN-RELEASING HORMONE (CRH), THUS PREVENTING CRH UPREGULATION UNDER CONDITIONS OF CHRONIC STRESS. CPGS MAPPING TO THE NR3C1 CGI SHORE REGION ARE DYNAMICALLY REGULATED BY ELS AND UNDERPIN METHYLATION-SENSITIVE CONTROL OF THIS REGION'S INSULATION-LIKE FUNCTION VIA YING YANG 1 (YY1) BINDING. OUR RESULTS PROVIDE NEW INSIGHT INTO HOW A GENOMIC ELEMENT INTEGRATES EXPERIENCE-DEPENDENT EPIGENETIC PROGRAMMING OF THE COMPOSITE PROXIMAL NR3C1 PROMOTER, AND ASSIGNS AN INSULATING ROLE TO THE CGI SHORE. 2015 12 6266 15 THE NEUROBIOLOGY OF SUICIDE. THE STRESS-DIATHESIS MODEL POSITS THAT SUICIDE IS THE RESULT OF AN INTERACTION BETWEEN STATE-DEPENDENT (ENVIRONMENTAL) STRESSORS AND A TRAIT-LIKE DIATHESIS OR SUSCEPTIBILITY TO SUICIDAL BEHAVIOUR, INDEPENDENT OF PSYCHIATRIC DISORDERS. FINDINGS FROM POST-MORTEM STUDIES OF THE BRAIN AND FROM GENOMIC AND IN-VIVO NEUROIMAGING STUDIES INDICATE A BIOLOGICAL BASIS FOR THIS DIATHESIS, INDICATING THE IMPORTANCE OF NEUROBIOLOGICAL SCREENING AND INTERVENTIONS, IN ADDITION TO COGNITIVE AND MOOD INTERVENTIONS, IN THE PREVENTION OF SUICIDE. EARLY-LIFE ADVERSITY AND EPIGENETIC MECHANISMS MIGHT EXPLAIN SOME OF THE LINK BETWEEN SUICIDE RISK AND BRAIN CIRCUITRY AND NEUROCHEMISTRY ABNORMALITIES. RESULTS FROM A RANGE OF STUDIES USING DIVERSE DESIGNS AND POST-MORTEM AND IN-VIVO TECHNIQUES SHOW IMPAIRMENTS OF THE SEROTONIN NEUROTRANSMITTER SYSTEM AND THE HYPOTHALAMIC-PITUITARY-ADRENAL AXIS STRESS-RESPONSE SYSTEM IN THE DIATHESIS FOR SUICIDAL BEHAVIOUR. THESE IMPAIRMENTS MANIFEST AS IMPAIRED COGNITIVE CONTROL OF MOOD, PESSIMISM, REACTIVE AGGRESSIVE TRAITS, IMPAIRED PROBLEM SOLVING, OVER-REACTIVITY TO NEGATIVE SOCIAL SIGNS, EXCESSIVE EMOTIONAL PAIN, AND SUICIDAL IDEATION, LEADING TO SUICIDAL BEHAVIOUR. BIOMARKERS RELATED TO THE DIATHESIS MIGHT HELP TO INFORM RISK-ASSESSMENT PROCEDURES AND TREATMENT CHOICE IN THE PREVENTION OF SUICIDE. 2014 13 3463 17 HYPOTHALAMIC-PITUITARY-ADRENAL AND HYPOTHALAMIC-PITUITARY-GONADAL AXES: SEX DIFFERENCES IN REGULATION OF STRESS RESPONSIVITY. GONADAL HORMONES PLAY A KEY ROLE IN THE ESTABLISHMENT, ACTIVATION, AND REGULATION OF THE HYPOTHALAMIC-PITUITARY-ADRENAL (HPA) AXIS. BY INFLUENCING THE RESPONSE AND SENSITIVITY TO RELEASING FACTORS, NEUROTRANSMITTERS, AND HORMONES, GONADAL STEROIDS HELP ORCHESTRATE THE GAIN OF THE HPA AXIS TO FINE-TUNE THE LEVELS OF STRESS HORMONES IN THE GENERAL CIRCULATION. FROM EARLY LIFE TO ADULTHOOD, GONADAL STEROIDS CAN DIFFERENTIALLY AFFECT THE HPA AXIS, RESULTING IN SEX DIFFERENCES IN THE RESPONSIVITY OF THIS AXIS. THE HPA AXIS INFLUENCES MANY PHYSIOLOGICAL FUNCTIONS MAKING AN ORGANISM'S RESPONSE TO CHANGES IN THE ENVIRONMENT APPROPRIATE FOR ITS REPRODUCTIVE STATUS. ALTHOUGH THE ACUTE HPA RESPONSE TO STRESSORS IS A BENEFICIAL RESPONSE, CONSTANT ACTIVATION OF THIS CIRCUITRY BY CHRONIC OR TRAUMATIC STRESSFUL EPISODES MAY LEAD TO A DYSREGULATION OF THE HPA AXIS AND CAUSE PATHOLOGY. COMPARED TO MALES, FEMALE MICE AND RATS SHOW A MORE ROBUST HPA AXIS RESPONSE, AS A RESULT OF CIRCULATING ESTRADIOL LEVELS WHICH ELEVATE STRESS HORMONE LEVELS DURING NON-THREATENING SITUATIONS, AND DURING AND AFTER STRESSORS. FLUCTUATING LEVELS OF GONADAL STEROIDS IN FEMALES ACROSS THE ESTROUS CYCLE ARE A MAJOR FACTOR CONTRIBUTING TO SEX DIFFERENCES IN THE ROBUSTNESS OF HPA ACTIVITY IN FEMALES COMPARED TO MALES. MOREOVER, GONADAL STEROIDS MAY ALSO CONTRIBUTE TO EPIGENETIC AND ORGANIZATIONAL INFLUENCES ON THE HPA AXIS EVEN BEFORE PUBERTY. CORRESPONDINGLY, CROSSTALK BETWEEN THE HYPOTHALAMIC-PITUITARY-GONADAL (HPG) AND HPA AXES COULD LEAD TO ABNORMALITIES OF STRESS RESPONSES. IN HUMANS, A DYSREGULATED STRESS RESPONSE IS ONE OF THE MOST COMMON SYMPTOMS SEEN ACROSS MANY NEUROPSYCHIATRIC DISORDERS, AND AS A RESULT, SUCH INTERACTIONS MAY EXACERBATE PERIPHERAL PATHOLOGIES. IN THIS REVIEW, WE DISCUSS THE HPA AND HPG AXES AND REVIEW HOW GONADAL STEROIDS INTERACT WITH THE HPA AXIS TO REGULATE THE STRESS CIRCUITRY DURING ALL STAGES IN LIFE. 2017 14 4935 17 PATERNAL COCAINE TAKING ELICITS EPIGENETIC REMODELING AND MEMORY DEFICITS IN MALE PROGENY. PATERNAL ENVIRONMENTAL PERTURBATIONS INCLUDING EXPOSURE TO DRUGS OF ABUSE CAN PRODUCE PROFOUND EFFECTS ON THE PHYSIOLOGY AND BEHAVIOR OF OFFSPRING VIA EPIGENETIC MODIFICATIONS. HERE WE SHOW THAT ADULT DRUG-NAIVE MALE OFFSPRING OF COCAINE-EXPOSED SIRES HAVE MEMORY FORMATION DEFICITS AND ASSOCIATED REDUCTIONS IN NMDA RECEPTOR-MEDIATED HIPPOCAMPAL SYNAPTIC PLASTICITY. REDUCED LEVELS OF THE ENDOGENOUS NMDA RECEPTOR CO-AGONIST D-SERINE WERE ACCOMPANIED BY INCREASED EXPRESSION OF THE D-SERINE DEGRADING ENZYME D-AMINO ACID OXIDASE (DAO1) IN THE HIPPOCAMPUS OF COCAINE-SIRED MALE PROGENY. INCREASED DAO1 TRANSCRIPTION WAS ASSOCIATED WITH ENRICHMENT OF PERMISSIVE EPIGENETIC MARKS ON HISTONE PROTEINS IN THE HIPPOCAMPUS OF MALE COCAINE-SIRED PROGENY, SOME OF WHICH WERE ENHANCED NEAR THE DAO1 LOCUS. FINALLY, HIPPOCAMPAL ADMINISTRATION OF D-SERINE REVERSED BOTH THE MEMORY FORMATION AND SYNAPTIC PLASTICITY DEFICITS. COLLECTIVELY, THESE RESULTS DEMONSTRATE THAT PATERNAL COCAINE EXPOSURE PRODUCES EPIGENETIC REMODELING IN THE HIPPOCAMPUS LEADING TO NMDA RECEPTOR-DEPENDENT MEMORY FORMATION AND SYNAPTIC PLASTICITY IMPAIRMENTS ONLY IN MALE PROGENY, WHICH HAS SIGNIFICANT IMPLICATIONS FOR THE MALE DESCENDANTS OF CHRONIC COCAINE USERS. 2017 15 2905 17 GENE DYSREGULATION IN THE ADULT RAT PARAVENTRICULAR NUCLEUS AND AMYGDALA BY PRENATAL EXPOSURE TO DEXAMETHASONE. FETAL PROGRAMMING IS THE CONCEPT THAT MATERNAL STRESSORS DURING CRITICAL PERIODS OF FETAL DEVELOPMENT CAN ALTER OFFSPRING PHENOTYPES POSTNATALLY. EXCESS GLUCOCORTICOIDS CAN INTERACT WITH THE FETUS TO EFFECT GENETIC AND EPIGENETIC CHANGES IMPLICATED IN ADVERSE DEVELOPMENTAL OUTCOMES. THE PRESENT STUDY INVESTIGATES HOW CHRONIC EXPOSURE TO THE SYNTHETIC GLUCOCORTICOID DEXAMETHASONE DURING LATE GESTATION ALTERS THE EXPRESSION OF GENES RELATED TO BEHAVIOR IN BRAIN AREAS RELEVANT TO THE REGULATION AND FUNCTION OF THE HYPOTHALAMIC-PITUITARY-ADRENAL AXIS. PREGNANT WISTAR KYOTO RATS RECEIVED SUBCUTANEOUS INJECTIONS OF DEXAMETHASONE (100 MUG/KG) DAILY FROM GESTATIONAL DAY 15-21 OR VEHICLE ONLY AS SHAM CONTROLS. THE AMYGDALA AND PARAVENTRICULAR NUCLEUS (PVN) WERE MICRO-PUNCHED TO EXTRACT MRNA FOR REVERSE TRANSCRIPTION AND QUANTITATIVE POLYMERASE CHAIN REACTION FOR THE ANALYSIS OF THE EXPRESSION OF SPECIFIC GENES. IN THE PVN, THE EXPRESSION OF THE GLUCOCORTICOID RECEPTOR NR3C1 WAS DOWNREGULATED IN FEMALE RATS IN RESPONSE TO PROGRAMMING. THE EXPRESSION OF CACNA1C ENCODING THE CA(V)1.2 PORE SUBUNIT OF L-TYPE VOLTAGE-GATED CALCIUM CHANNELS WAS DOWNREGULATED IN MALE AND FEMALE RATS PRENATALLY EXPOSED TO DEXAMETHASONE. COLLECTIVELY, THE RESULTS SUGGEST THAT PRENATAL EXPOSURE TO ELEVATED LEVELS OF GLUCOCORTICOIDS PLAYS A ROLE IN THE DYSREGULATION OF THE HYPOTHALAMIC-PITUITARY-ADRENAL AXIS AND POTENTIALLY LEARNING AND MEMORY BY ALTERING THE EXPRESSION OF SPECIFIC GENES WITHIN THE AMYGDALA AND PVN. 2022 16 1466 12 DISTINCT ACTIONS OF ANCESTRAL VINCLOZOLIN AND JUVENILE STRESS ON NEURAL GENE EXPRESSION IN THE MALE RAT. EXPOSURE TO THE ENDOCRINE DISRUPTING CHEMICAL VINCLOZOLIN DURING GESTATION OF AN F0 GENERATION AND/OR CHRONIC RESTRAINT STRESS DURING ADOLESCENCE OF THE F3 DESCENDANTS AFFECTS BEHAVIOR, PHYSIOLOGY, AND GENE EXPRESSION IN THE BRAIN. GENES RELATED TO THE NETWORKS OF GROWTH FACTORS, SIGNALING PEPTIDES, AND RECEPTORS, STEROID HORMONE RECEPTORS AND ENZYMES, AND EPIGENETIC RELATED FACTORS WERE MEASURED USING QUANTITATIVE POLYMERASE CHAIN REACTION VIA TAQMAN LOW DENSITY ARRAYS TARGETING 48 GENES IN THE CENTRAL AMYGDALOID NUCLEUS, MEDIAL AMYGDALOID NUCLEUS, MEDIAL PREOPTIC AREA (MPOA), LATERAL HYPOTHALAMUS (LH), AND THE VENTROMEDIAL NUCLEUS OF THE HYPOTHALAMUS. WE FOUND THAT GROWTH FACTORS ARE PARTICULARLY VULNERABLE TO ANCESTRAL EXPOSURE IN THE CENTRAL AND MEDIAL AMYGDALA; RESTRAINT STRESS DURING ADOLESCENCE AFFECTED NEURAL GROWTH FACTORS IN THE MEDIAL AMYGDALA. SIGNALING PEPTIDES WERE AFFECTED BY BOTH ANCESTRAL EXPOSURE AND STRESS DURING ADOLESCENCE PRIMARILY IN HYPOTHALAMIC NUCLEI. STEROID HORMONE RECEPTORS AND ENZYMES WERE STRONGLY AFFECTED BY RESTRAINT STRESS IN THE MPOA. EPIGENETIC RELATED GENES WERE AFFECTED BY STRESS IN THE VENTROMEDIAL NUCLEUS AND BY BOTH ANCESTRAL EXPOSURE AND STRESS DURING ADOLESCENCE INDEPENDENTLY IN THE CENTRAL AMYGDALA. IT IS NOTEWORTHY THAT THE LH SHOWED NO EFFECTS OF EITHER MANIPULATION. GENE EXPRESSION IS DISCUSSED IN THE CONTEXT OF BEHAVIORAL AND PHYSIOLOGICAL MEASURES PREVIOUSLY PUBLISHED. 2015 17 4945 12 PATERNAL PRECONCEPTION EVERY-OTHER-DAY ETHANOL DRINKING ALTERS BEHAVIOR AND ETHANOL CONSUMPTION IN OFFSPRING. ALCOHOL USE DISORDER IS A DEVASTATING DISEASE WITH A COMPLEX ETIOLOGY. RECENT PRECLINICAL STUDIES HAVE REVEALED THAT PATERNAL PRECONCEPTION CHRONIC INTERMITTENT ETHANOL (ETOH) EXPOSURE VIA VAPORIZED ETOH ALTERED DRINKING BEHAVIORS AND SENSITIVITY TO ETOH SELECTIVELY IN MALE OFFSPRING. IN THE CURRENT STUDY, WE USED A VOLUNTARY ORAL ROUTE OF PATERNAL PRECONCEPTION ETOH EXPOSURE, I.E., INTERMITTENT EVERY-OTHER-DAY TWO-BOTTLE CHOICE DRINKING, AND TESTED OFFSPRING FOR BEHAVIORAL ALTERATIONS. FIFTEEN ETOH DRINKING SIRES AND 10 CONTROL SIRES WERE MATED TO ETOH NAIVE FEMALES TO PRODUCE ETOH-SIRED AND CONTROL-SIRED OFFSPRING. THESE OFFSPRING WERE TESTED USING THE ELEVATED PLUS MAZE, OPEN FIELD, DRINKING IN THE DARK, AND UNLIMITED ACCESS TWO-BOTTLE CHOICE ASSAYS. WE FOUND THAT PATERNAL PRECONCEPTION EVERY-OTHER-DAY TWO-BOTTLE CHOICE DRINKING RESULTED IN REDUCED ETOH CONSUMPTION SELECTIVELY IN MALE OFFSPRING IN THE DRINKING IN THE DARK ASSAY COMPARED TO CONTROL-SIRED OFFSPRING. NO DIFFERENCES WERE DETECTED IN EITHER SEX IN THE UNLIMITED ACCESS TWO-BOTTLE CHOICE AND ELEVATED PLUS MAZE ASSAYS. OPEN FIELD ANALYSIS REVEALED COMPLEX CHANGES IN BASAL BEHAVIOR AND ETOH-INDUCED BEHAVIORS THAT WERE SEX SPECIFIC. WE CONCLUDED THAT PATERNAL PRECONCEPTION VOLUNTARY ETOH CONSUMPTION HAS PERSISTENT EFFECTS THAT IMPACT THE NEXT GENERATION. THIS STUDY ADDS TO A GROWING APPRECIATION THAT ONE'S BEHAVIORAL RESPONSE TO ETOH AND ETOH DRINKING BEHAVIOR ARE IMPACTED BY ETOH EXPOSURE OF THE PRIOR GENERATION. 2019 18 4930 15 PATERNAL ALCOHOL EXPOSURE REDUCES ACQUISITION OF OPERANT ALCOHOL SELF-ADMINISTRATION AND AFFECTS BDNF DNA METHYLATION IN MALE AND FEMALE OFFSPRING. FAMILIAL TRANSMISSION OF ALCOHOL USE DISORDER REFLECTS GENETIC AND ENVIRONMENTAL FACTORS. PATERNAL ALCOHOL EXPOSURE MAY AFFECT RODENT OFFSPRING VIA EPIGENETIC MODIFICATIONS TRANSMITTED THROUGH THE MALE GERM LINE. WHILE SUCH EXPOSURE ALTERS ALCOHOL SENSITIVITY IN MOUSE OFFSPRING, NO STUDIES EXAMINED IF IT IMPACTS THE DEVELOPMENT OF OPERANT ALCOHOL SELF-ADMINISTRATION IN RATS. WE EXPOSED MALE (SIRES) WISTAR RATS TO CHRONIC INTERMITTENT ETHANOL IN VAPOUR CHAMBERS (16 H/DAY; 5 DAYS/WEEK) OR TO AIR FOR 6 WEEKS. EIGHT WEEKS LATER, RATS WERE MATED WITH ALCOHOL-NAIVE FEMALES. ADULT ALCOHOL- AND CONTROL-SIRED F1 OFFSPRING WERE ASSESSED IN ACQUISITION OF ALCOHOL SELF-ADMINISTRATION IN WHICH INCREASING ALCOHOL CONCENTRATIONS (2.5%, 5% AND 10%, V/V) WERE DELIVERED AFTER ONE LEVER PRESS (FIXED RATIO 1 OR FR1). PRIOR TO ALCOHOL SESSIONS, RATS WERE TRAINED TO LEVER PRESS FOR FOOD DELIVERY UNDER AN FR1 SCHEDULE OF REINFORCEMENT. DNA METHYLATION LEVELS OF THE BRAIN DERIVED NEUROTROPHIC FACTOR (BDNF) GENE WERE MEASURED IN SPERM, NUCLEUS ACCUMBENS (NAC) AND MEDIAL PREFRONTAL CORTEX (MPFC) IN SIRES AND IN OFFSPRING. ALCOHOL-EXPOSED SIRES HAD LOWER BDNF DNA METHYLATION LEVELS IN NAC AND GREATER METHYLATION LEVELS IN MPFC. ALTHOUGH THIS PATTERN WAS NOT RECAPITULATED IN OFFSPRING, ALCOHOL-SIRED OFFSPRING OF BOTH SEXES DID SHOW ABERRANT BDNF DNA METHYLATION PATTERNS COMPARED TO CONTROL-SIRED OFFSPRING. ALCOHOL-SIRED OFFSPRING SELF-ADMINISTERED LESS ALCOHOL (5% AND 10%) WITH NO GROUP DIFFERENCES IN FOOD RESPONDING. RESULTS INDICATE THAT PATERNAL ALCOHOL EXPOSURE PRIOR TO CONCEPTION PROTECTS AGAINST ALCOHOL'S INITIAL REINFORCING EFFECTS BUT THE PATTERN OF DYSREGULATED BDNF METHYLATION IN REWARD-RELATED CIRCUITRY DID NOT MIMIC CHANGES SEEN IN SIRES. 2022 19 1197 17 CORTICOSTERONE INDUCES DISCRETE EPIGENETIC SIGNATURES IN THE DORSAL AND VENTRAL HIPPOCAMPUS THAT DEPEND UPON SEX AND GENOTYPE: FOCUS ON METHYLATED NR3C1 GENE. THE GENOMIC EFFECTS OF CIRCULATING GLUCOCORTICOIDS ARE PARTICULARLY RELEVANT IN CORTICO-LIMBIC STRUCTURES, WHICH EXPRESS A HIGH CONCENTRATION OF STEROID HORMONE RECEPTORS. TO DATE, NO STUDIES HAVE INVESTIGATED GENOMIC DIFFERENCES IN HIPPOCAMPAL SUBREGIONS, NAMELY THE DORSAL (DHPC) AND VENTRAL (VHPC) HIPPOCAMPUS, IN PRECLINICAL MODELS TREATED WITH EXOGENOUS GLUCOCORTICOIDS. CHRONIC ORAL CORTICOSTERONE (CORT) IN MOUSE IS A PHARMACOLOGICAL APPROACH THAT DISRUPTS THE ACTIVITY OF THE HYPOTHALAMIC-PITUITARY-ADRENAL AXIS, INCREASES AFFECTIVE BEHAVIOR, AND INDUCES GENOMIC CHANGES AFTER STRESS IN THE HPC OF WILDTYPE (WT) MICE AND MICE HETEROZYGOUS FOR THE GENE CODING FOR BRAIN-DERIVED NEUROTROPHIC FACTOR VAL66MET (HMET), A VARIANT ASSOCIATED WITH GENETIC SUSCEPTIBILITY TO STRESS. USING RNA-SEQUENCING, WE INVESTIGATED THE GENOMIC SIGNATURES OF ORAL CORT IN THE DHPC AND VHPC OF WT AND HMET MALE AND FEMALE MICE, AND EXAMINED SEX AND GENOTYPE DIFFERENCES IN RESPONSE TO ORAL CORT. MALES UNDER CORT SHOWED LOWER GLYCEMIA AND INCREASED ANXIETY- AND DEPRESSION-LIKE BEHAVIOR COMPARED TO FEMALES THAT SHOWED INSTEAD OPPOSITE AFFECTIVE BEHAVIOR IN RESPONSE TO CORT. RANK-RANK-HYPERGEOMETRIC OVERLAP (RRHO) WAS USED TO IDENTIFY GENES FROM A CONTINUOUS GRADIENT OF SIGNIFICANCY THAT WERE CONCORDANT ACROSS GROUPS. RRHO SHOWED THAT CORT-INDUCED DIFFERENTIALLY EXPRESSED GENES (DEGS) IN WT MICE AND HMET MICE CONVERGED IN THE DHPC OF MALES AND FEMALES, WHILE IN THE VHPC, DEGS CONVERGED IN MALES AND DIVERGED IN FEMALES. THE VHPC SHOWED A HIGHER NUMBER OF DEGS COMPARED TO THE DHPC AND EXHIBITED SEX DIFFERENCES RELATED TO GLUCOCORTICOID RECEPTOR (GR)-BINDING GENES AND EPIGENETIC MODIFIERS. METHYL-DNA-IMMUNOPRECIPITATION IN THE VHPC REVEALED DIFFERENTIAL METHYLATION OF THE EXONS 1(C) AND 1(F) OF THE GR GENE (NR3C1) IN HMET FEMALES. TOGETHER, WE REPORT BEHAVIORAL AND ENDOCRINOLOGICAL SEX DIFFERENCES IN RESPONSE TO CORT, AS WELL AS EPIGENETIC SIGNATURES THAT I) DIFFER IN THE DHPC AND VHPC,II) ARE DISTINCT IN MALES AND FEMALES, AND III) IMPLICATE DIFFERENTIAL METHYLATION OF NR3C1 SELECTIVELY IN HMET FEMALES. 2022 20 3092 18 GENOMIC AND EPIGENOMIC MECHANISMS OF GLUCOCORTICOIDS IN THE BRAIN. FOLLOWING THE DISCOVERY OF GLUCOCORTICOID RECEPTORS IN THE HIPPOCAMPUS AND OTHER BRAIN REGIONS, RESEARCH HAS FOCUSED ON UNDERSTANDING THE EFFECTS OF GLUCOCORTICOIDS IN THE BRAIN AND THEIR ROLE IN REGULATING EMOTION AND COGNITION. GLUCOCORTICOIDS ARE ESSENTIAL FOR ADAPTATION TO STRESSORS (ALLOSTASIS) AND IN MALADAPTATION RESULTING FROM ALLOSTATIC LOAD AND OVERLOAD. ALLOSTATIC OVERLOAD, WHICH CAN OCCUR DURING CHRONIC STRESS, CAN RESHAPE THE HYPOTHALAMIC-PITUITARY-ADRENAL AXIS THROUGH EPIGENETIC MODIFICATION OF GENES IN THE HIPPOCAMPUS, HYPOTHALAMUS AND OTHER STRESS-RESPONSIVE BRAIN REGIONS. GLUCOCORTICOIDS EXERT THEIR EFFECTS ON THE BRAIN THROUGH GENOMIC MECHANISMS THAT INVOLVE BOTH GLUCOCORTICOID RECEPTORS AND MINERALOCORTICOID RECEPTORS DIRECTLY BINDING TO DNA, AS WELL AS BY NON-GENOMIC MECHANISMS. FURTHERMORE, GLUCOCORTICOIDS SYNERGIZE BOTH GENOMICALLY AND NON-GENOMICALLY WITH NEUROTRANSMITTERS, NEUROTROPHIC FACTORS, SEX HORMONES AND OTHER STRESS MEDIATORS TO SHAPE AN ORGANISM'S PRESENT AND FUTURE RESPONSES TO A STRESSFUL ENVIRONMENT. HERE, WE DISCUSS THE MECHANISMS OF GLUCOCORTICOID ACTION IN THE BRAIN AND REVIEW HOW GLUCOCORTICOIDS INTERACT WITH STRESS MEDIATORS IN THE CONTEXT OF ALLOSTASIS, ALLOSTATIC LOAD AND STRESS-INDUCED NEUROPLASTICITY. 2017