1 5142 103 POTENTIAL ROLE FOR HISTONE DEACETYLATION IN CHRONIC DIAZEPAM-INDUCED DOWNREGULATION OF ALPHA1-GABA(A) RECEPTOR SUBUNIT EXPRESSION. CORROBORATING EVIDENCE INDICATE THAT THE DOWNREGULATION OF GABA(A) RECEPTOR SUBUNIT EXPRESSION MAY UNDERLIE TOLERANCE TO THE ANTICONVULSANT AND ANXIOLYTIC ACTIONS OF BENZODIAZEPINE (BZ) LIGANDS THAT ACT AS FULL ALLOSTERIC MODULATORS (FAMS) OF GABA ACTIONS AT A VARIETY OF GABA(A) RECEPTOR SUBTYPES. WE AND OTHERS HAVE SHOWN THAT 10-14 DAYS TREATMENT WITH INCREASING DOSES OF DIAZEPAM (A FAM) RESULTED IN ANTICONVULSANT TOLERANCE AND DECREASED THE EXPRESSION OF THE ALPHA1 GABA(A) RECEPTOR SUBUNIT MRNA AND PROTEIN IN FRONTAL CORTEX. IN ADDITION, WE HAVE ALSO SHOWN THAT LONG-TERM TREATMENT WITH IMIDAZENIL, A PARTIAL ALLOSTERIC MODULATOR OF GABA ACTION AT SELECTIVE GABA(A) RECEPTOR SUBTYPES, FAIL TO CHANGE THE EXPRESSION OF THE ALPHA1 SUBUNIT MRNA OR INDUCE TOLERANCE TO ITS ANTICONVULSANT OR ANXIOLYTIC ACTION. HOWEVER, LITTLE IS KNOWN REGARDING THE POTENTIAL ROLE OF EPIGENETIC MECHANISMS ON LONG-TERM BZ-INDUCED DOWNREGULATION OF GABA(A) RECEPTOR SUBUNIT. THEREFORE, WE EXAMINED THE ROLE OF HISTONE ACETYLATION AND DNA METHYLATION MECHANISMS ON LONG-TERM DIAZEPAM-INDUCED DOWNREGULATION OF THE ALPHA1 SUBUNIT MRNA EXPRESSION IN RAT FRONTAL CORTEX. WE FOUND THAT 10 DAYS TREATMENT WITH INCREASING DOSES OF DIAZEPAM BUT NOT IMIDAZENIL DECREASED THE EXPRESSION OF THE ALPHA1 GABA(A) RECEPTOR SUBUNIT MRNA AND PROMOTER ACETYLATION IN FRONTAL CORTEX. IN ADDITION, WE ALSO FOUND THAT 10 DAYS TREATMENT WITH DIAZEPAM BUT NOT IMIDAZENIL INCREASED THE EXPRESSION OF HISTONE DEACETYLASE (HDAC) 1 AND 2 IN FRONTAL CORTEX. THUS, THE INCREASED EXPRESSION OF HDAC1 AND HDAC2 (CLASS 1 HDACS) AND CONSEQUENTLY INCREASED HISTONE DEACETYLATION MECHANISM OF THIS CLASS 1 HDACS, MAY UNDERLIE LONG-TERM DIAZEPAM-INDUCED DECREASED EXPRESSION OF THE ALPHA1 GABA(A) RECEPTOR SUBUNIT MRNA IN FRONTAL CORTEX. 2018 2 6352 27 THE ROLE OF GABA(A) RECEPTORS IN THE DEVELOPMENT OF ALCOHOLISM. ALCOHOLISM IS A COMMON, HERITABLE, CHRONIC RELAPSING DISORDER. GABA(A) RECEPTORS UNDERGO ALLOSTERIC MODULATION BY ETHANOL, ANESTHETICS, BENZODIAZEPINES AND NEUROSTEROIDS AND HAVE BEEN IMPLICATED IN THE ACUTE AS WELL AS THE CHRONIC EFFECTS OF ETHANOL INCLUDING TOLERANCE, DEPENDENCE AND WITHDRAWAL. MEDICATIONS TARGETING GABA(A) RECEPTORS AMELIORATE THE SYMPTOMS OF ACUTE WITHDRAWAL. ETHANOL INDUCES PLASTICITY IN GABA(A) RECEPTORS: TOLERANCE IS ASSOCIATED WITH GENERALLY DECREASED GABA(A) RECEPTOR ACTIVATION AND DIFFERENTIALLY ALTERED SUBUNIT EXPRESSION. THE DOPAMINE (DA) MESOLIMBIC REWARD PATHWAY ORIGINATING IN THE VENTRAL TEGMENTAL AREA (VTA), AND INTERACTING STRESS CIRCUITRY PLAY AN IMPORTANT ROLE IN THE DEVELOPMENT OF ADDICTION. VTA GABAERGIC INTERNEURONS ARE THE PRIMARY INHIBITORY REGULATORS OF DA NEURONS AND A SUBSET OF VTA GABA(A) RECEPTORS MAY BE IMPLICATED IN THE SWITCH FROM HEAVY DRINKING TO DEPENDENCE. GABA(A) RECEPTORS MODULATE ANXIETY AND RESPONSE TO STRESS; IMPORTANT ELEMENTS OF SUSTAINED DRINKING AND RELAPSE. THE GABA(A) RECEPTOR SUBUNIT GENES CLUSTERED ON CHROMOSOME 4 ARE HIGHLY EXPRESSED IN THE REWARD PATHWAY. SEVERAL RECENT STUDIES HAVE PROVIDED STRONG EVIDENCE THAT ONE OF THESE GENES, GABRA2, IS IMPLICATED IN ALCOHOLISM IN HUMANS. THE INFLUENCE OF THE INTERACTION BETWEEN ETHANOL AND GABA(A) RECEPTORS IN THE REWARD PATHWAY ON THE DEVELOPMENT OF ALCOHOLISM TOGETHER WITH GENETIC AND EPIGENETIC VULNERABILITIES WILL BE EXPLORED IN THIS REVIEW. 2008 3 5039 24 PHARMACOGENETICS OF CHRONIC PAIN MANAGEMENT. OBJECTIVE: THE EXPERIENCE OF CHRONIC PAIN IS ONE OF THE COMMONEST REASONS INDIVIDUALS SEEK MEDICAL ATTENTION, MAKING THE MANAGEMENT OF CHRONIC PAIN A MAJOR ISSUE IN CLINICAL PRACTICE. DRUG METABOLISM AND RESPONSES ARE AFFECTED BY MANY FACTORS, WITH GENETIC VARIATIONS OFFERING ONLY A PARTIAL EXPLANATION OF AN INDIVIDUAL'S RESPONSE. THERE IS A PAUCITY OF EVIDENCE FOR THE BENEFITS OF PHARMACOGENETIC TESTING IN THE CONTEXT OF PAIN MANAGEMENT. DESIGN AND METHODS: WE REVIEWED THE LITERATURE BETWEEN 2000 AND 2013, AND REFERENCES CITED THEREIN, USING VARIOUS KEYWORDS RELATED TO PAIN MANAGEMENT, PHARMACOLOGY AND PHARMACOGENETICS. RESULTS: OPIOIDS CONTINUE TO BE THE MAINSTAY OF CHRONIC PAIN MANAGEMENT. SEVERAL NON-OPIOID BASED THERAPIES, SUCH AS TREATMENT WITH CANNABINOIDS, GENE THERAPY AND EPIGENETIC-BASED APPROACHES ARE NOW AVAILABLE FOR THESE PATIENTS. ADJUVANT THERAPIES WITH ANTIDEPRESSANTS, BENZODIAZEPINES OR ANTICONVULSANTS CAN ALSO BE USEFUL IN MANAGING PAIN. CURRENTLY, LABORATORY MONITORING OF PAIN MANAGEMENT PATIENTS, IF PERFORMED, IS LARGELY THROUGH URINE DRUG MEASUREMENTS. CONCLUSIONS: DRUG HALF-LIFE CALCULATIONS CAN BE USED AS FUNCTIONAL MARKERS OF THE CUMULATIVE EFFECT OF PHARMACOGENETICS AND DRUG-DRUG INTERACTIONS. ASSESSMENT OF HALF-LIFE AND THERAPEUTIC EFFECTS MAY BE MORE USEFUL THAN GENETIC TESTING IN PREVENTING ADVERSE DRUG REACTIONS TO PAIN MEDICATIONS, WHILE ENSURING EFFECTIVE ANALGESIA. DEFINITIVE, MASS SPECTROMETRY-BASED METHODS, CAPABLE OF MEASURING PARENT DRUG AND METABOLITE LEVELS, ARE THE MOST USEFUL ASSAYS FOR THIS PURPOSE. URINE DRUG MEASUREMENTS DO NOT NECESSARILY CORRELATE WITH SERUM DRUG CONCENTRATIONS OR THERAPEUTIC EFFECTS. THEREFORE, THEY ARE LIMITED IN THEIR USE IN MONITORING EFFICACY AND TOXICITY. 2014 4 3331 34 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 5 3346 39 HISTONE DEACETYLASES MEDIATE GABA(A) RECEPTOR EXPRESSION, PHYSIOLOGY, AND BEHAVIORAL MALADAPTATIONS IN RAT MODELS OF ALCOHOL DEPENDENCE. ALCOHOL USE DISORDERS ARE CHRONIC DEBILITATING DISEASES CHARACTERIZED BY SEVERE WITHDRAWAL SYMPTOMS THAT CONTRIBUTE TO MORBIDITY AND RELAPSE. GABA(A) RECEPTOR (GABA(A)R) ADAPTATIONS HAVE LONG BEEN IMPLICATED IN THE CHRONIC EFFECTS OF ALCOHOL AND CONTRIBUTE TO MANY WITHDRAWAL SYMPTOMS ASSOCIATED WITH ALCOHOL DEPENDENCE. IN RODENTS, GABA(A)R HYPOFUNCTION RESULTS FROM DECREASES IN GABRA1 EXPRESSION, ALTHOUGH THE UNDERLYING MECHANISM CONTROLLING GABRA1 EXPRESSION AFTER CHRONIC ETHANOL EXPOSURE IS STILL UNKNOWN. WE FOUND THAT CHRONIC ETHANOL EXPOSURE USING EITHER ETHANOL GAVAGE OR TWO-BOTTLE CHOICE VOLUNTARY ACCESS PARADIGMS DECREASED GABRA1 EXPRESSION AND INCREASED HDAC2 AND HDAC3 EXPRESSION. ADMINISTRATION OF THE HDAC INHIBITOR TRICHOSTATIN A (TSA) AFTER CHRONIC ETHANOL EXPOSURE PREVENTS THE DECREASE IN GABRA1 EXPRESSION AND FUNCTION AS WELL AS THE INCREASE IN HDAC2 AND HDAC3 EXPRESSION IN BOTH THE CORTEX AND THE MEDIAL PREFRONTAL CORTEX (MPFC). CHRONIC ETHANOL EXPOSURE AND WITHDRAWAL, BUT NOT ACUTE ETHANOL EXPOSURE OR ACUTE WITHDRAWAL, CAUSE A SELECTIVE UPREGULATION OF HDAC2 AND HDAC3 ASSOCIATED WITH THE GABRA1 PROMOTER THAT ACCOMPANIES A DECREASE IN H3 ACETYLATION OF THE GABRA1 PROMOTER AND THE REDUCTION IN GABA(A)R ALPHA1 SUBUNIT EXPRESSION. TSA ADMINISTRATION PREVENTED EACH OF THESE MOLECULAR EVENTS AS WELL AS BEHAVIORAL MANIFESTATIONS OF ETHANOL DEPENDENCE, INCLUDING TOLERANCE TO ZOLPIDEM-INDUCED LOSS OF RIGHTING REFLEX, REDUCED OPEN-ARM TIME IN THE ELEVATED PLUS MAZE, REDUCED CENTER-TIME AND LOCOMOTOR ACTIVITY IN THE OPEN-FIELD ASSAY, AND TSA REDUCED VOLUNTARY ETHANOL CONSUMPTION. THE RESULTS SHOW HOW CHRONIC ETHANOL EXPOSURE REGULATES THE HIGHLY PROMINENT GABA(A)R ALPHA1 SUBUNIT BY AN EPIGENETIC MECHANISM THAT REPRESENTS A POTENTIAL TREATMENT MODALITY FOR ALCOHOL DEPENDENCE. 2018 6 5657 34 SEX-DEPENDENT PRONOCICEPTIVE ROLE OF SPINAL ALPHA(5) -GABA(A) RECEPTOR AND ITS EPIGENETIC REGULATION IN NEUROPATHIC RODENTS. EXTRASYNAPTIC ALPHA(5) -SUBUNIT CONTAINING GABA(A) (ALPHA(5) -GABA(A) ) RECEPTORS PARTICIPATE IN CHRONIC PAIN. PREVIOUSLY, WE REPORTED A SEX DIFFERENCE IN THE ACTION OF ALPHA(5) -GABA(A) RECEPTORS IN DYSFUNCTIONAL PAIN. HOWEVER, THE UNDERLYING MECHANISMS REMAIN UNKNOWN. THE AIM OF THIS STUDY WAS TO EXAMINE THIS SEXUAL DIMORPHISM IN NEUROPATHIC RODENTS AND THE MECHANISMS INVOLVED. FEMALE AND MALE WISTAR RATS OR ICR MICE WERE SUBJECTED TO NERVE INJURY FOLLOWED BY ALPHA(5) -GABA(A) RECEPTOR INVERSE AGONIST INTRATHECAL ADMINISTRATION, L-655,708. THE DRUG PRODUCED AN ANTIALLODYNIC EFFECT IN NERVE-INJURED FEMALE RATS AND MICE, AND A LOWER EFFECT IN MALES. WE HYPOTHESIZED THAT CHANGES IN ALPHA(5) -GABA(A) RECEPTOR, PROBABLY INFLUENCED BY HORMONAL AND EPIGENETIC STATUS, MIGHT UNDERLIE THIS SEX DIFFERENCE. THUS, WE PERFORMED QPCR AND WESTERN BLOT. NERVE INJURY INCREASED ALPHA(5) -GABA(A) MRNA AND PROTEIN IN FEMALE DORSAL ROOT GANGLIA (DRG) AND DECREASED THEM IN DRG AND SPINAL CORD OF MALES. TO INVESTIGATE THE HORMONAL INFLUENCE OVER ALPHA(5) -GABA(A) RECEPTOR ACTIONS, WE PERFORMED NERVE INJURY TO OVARIECTOMIZED RATS AND RECONSTITUTED THEM WITH 17BETA-ESTRADIOL (E2). OVARIECTOMY ABROGATED L-655,708 ANTIALLODYNIC EFFECT AND E2 RESTORED IT. OVARIECTOMY DECREASED ALPHA(5) -GABA(A) RECEPTOR AND ESTROGEN RECEPTOR ALPHA PROTEIN IN DRG OF NEUROPATHIC FEMALE RATS, WHILE E2 ENHANCED THEM. SINCE DNA METHYLATION MIGHT CONTRIBUTE TO ALPHA(5) -GABA(A) RECEPTOR DOWN-REGULATION IN MALES, WE EXAMINED CPG ISLAND DNA METHYLATION OF ALPHA(5) -GABA(A) RECEPTOR CODING GENE THROUGH PYROSEQUENCING. NERVE INJURY INCREASED METHYLATION IN MALE, BUT NOT FEMALE RATS. PHARMACOLOGICAL INHIBITION OF DNA METHYLTRANSFERASES INCREASED ALPHA(5) -GABA(A) RECEPTOR AND ENABLED L-655,708 ANTINOCICEPTIVE EFFECT IN MALE RATS. THESE RESULTS SUGGEST THAT ALPHA(5) -GABA(A) RECEPTOR IS A SUITABLE TARGET TO TREAT CHRONIC PAIN IN FEMALES. 2021 7 5201 32 PRENATAL MORPHINE EXPOSURE INCREASES GAMMA OSCILLATION AND THETA COHERENCE IN THE RAT REWARD SYSTEM. PREVIOUS STUDIES HAVE FOUND THAT PRENATAL MORPHINE (PNM) EXPOSURE LEADS TO BOTH INCREASED AND DECREASED RISK OF SUBSTANCE ABUSE IN OFFSPRING. UNDERSTANDING MORE ABOUT THE NEUROBIOLOGICAL CHANGES AFTER THE PNM EXPOSURE WOULD HELP TO UNDERSTAND MORE ABOUT THIS ISSUE. SIGNALING FROM DOPAMINE NEURONS OF THE VENTRAL TEGMENTAL AREA (VTA) IN THE MESOACCUMBAL AND MESOCORTICAL PATHWAYS PLAYS A VITAL ROLE IN DRUG DEPENDENCY. TO PROVIDE FURTHER KNOWLEDGE ABOUT THE EFFECTS OF PNM ON DRUG SEEKING BEHAVIOR AND THE DOPAMINE SYSTEM. WE RECORDED LOCAL FIELD POTENTIALS (LFP) SIMULTANEOUSLY IN THE VTA, NAC (NUCLEUS ACCUMBENS), BLA (BASOLATERAL AMYGDALA) AND MPFC (MEDIAL PREFRONTAL CORTEX) IN MALE ADULT RATS PRENATALLY TREATED WITH SALINE OR MORPHINE. MORPHINE (10 MG/KG) INDUCED CONDITIONED PLACE PREFERENCE (CPP) ESTABLISHMENT, EXTINCTION AND PRIMING WERE TESTED TO INVESTIGATE THE EFFECTS OF PNM ON ADDICTIVE-LIKE BEHAVIOR. IN ADDITION, THE EXPRESSION OF NUCLEAR HISTONE DEACETYLASES (HDAC4, HDAC5), WHICH PLAYS ESSENTIAL EPIGENETIC ROLES IN NEUROPLASTICITY AFTER DRUG USE WERE ALSO TESTED IN VTA AND NAC. THE RESULTS SHOWED THAT PNM DID NOT CHANGE THE ACQUISITION OF MORPHINE CPP IN MALE RATS, BUT IMPAIRED CPP EXTINCTION AND MORPHINE (5 MG/KG) - PRIMED REINSTATEMENT OF CPP AFTER EXTINCTION. PNM INCREASED THE LOW GAMMA (30-60 HZ) AND HIGH (60-90 HZ) GAMMA LFP POWERS IN NAC AND BLA. PNM ALSO LEADS TO INCREASED THETA (4-9 HZ) COHERENCE BETWEEN VTA AND NAC, AND INCREASED HDAC5 EXPRESSION IN VTA. AFTER CHRONIC MORPHINE ADMINISTRATION, COHERENCE BETWEEN VTA-NAC, MPFC-NAC AND MPFC-BLA INCREASED SIGNIFICANTLY IN PNS RATS, BUT NO CHANGES WERE FIND IN PNM RATS, INDICATING IMPAIRED PLASTICITY IN BRAIN CIRCUITS. ALL THESE RESULTS SUGGEST THAT PNM EXPOSURE INCREASED REWARD PROCESSING IN ADULT MALE RATS, BUT IMPAIRED MORPHINE CPP EXTINCTION AND REINSTATEMENT, WHICH RELATE TO DECREASES NETWORK PLASTICITY AND INCREASED HDAC5 EXPRESSION IN THE REWARD SYSTEM. 2022 8 893 30 CHRONIC ETHANOL EXPOSURE AND WITHDRAWAL IMPAIR SYNAPTIC GABA(A) RECEPTOR-MEDIATED NEUROTRANSMISSION IN DEEP-LAYER PREFRONTAL CORTEX. BACKGROUND: THE PREFRONTAL CORTEX (PFC) ACTS AS AN INTEGRATIVE HUB FOR THE PROCESSING OF CORTICAL AND SUBCORTICAL INPUT INTO MEANINGFUL EFFERENT SIGNALING, PERMITTING COMPLEX ASSOCIATIVE BEHAVIORS. PFC DYSFUNCTION IS CONSISTENTLY OBSERVED WITH ETHANOL (ETOH) DEPENDENCE AND IS A CORE COMPONENT OF THE PATHOLOGY OF ALCOHOL USE DISORDERS IN CURRENT MODELS OF ADDICTION. WHILE INTRACORTICAL GAMMA-AMINOBUTRYRIC ACID (GABA)ERGIC NEUROTRANSMISSION IS UNDERSTOOD TO BE ESSENTIAL FOR MAINTAINING COORDINATED NETWORK ACTIVITY WITHIN THE CORTEX, RELATIVELY LITTLE IS KNOWN REGARDING FUNCTIONAL GABAERGIC ADAPTATIONS IN PFC DURING ETOH DEPENDENCE. METHODS: IN THE PRESENT STUDY, MALE AND FEMALE (> POSTNATAL DAY 60) SPRAGUE-DAWLEY RATS WERE ADMINISTERED ETOH (5.0 G/KG; INTRAGASTRIC GAVAGE) FOR 14 TO 15 CONSECUTIVE DAYS. TWENTY-FOUR HOURS AFTER THE FINAL ADMINISTRATION, ANIMALS WERE SACRIFICED AND BRAINS EXTRACTED FOR ELECTROPHYSIOLOGICAL RECORDINGS OF ISOLATED GABA(A) RECEPTOR-MEDIATED CURRENTS OR ANALYSIS OF GABA(A) RECEPTOR SUBUNIT PROTEIN EXPRESSION IN DEEP-LAYER PFC NEURONS. RESULTS: CHRONIC ETOH EXPOSURE SIGNIFICANTLY ATTENUATED ACTIVITY-DEPENDENT SPONTANEOUS GABA(A) RECEPTOR-MEDIATED INHIBITORY POSTSYNAPTIC CURRENT (IPSC) FREQUENCY WITH NO EFFECT ON AMPLITUDE. FURTHERMORE, ANALYSIS OF IPSC DECAY KINETICS REVEALED A SIGNIFICANT ENHANCEMENT OF IPSC DECAY TIME THAT WAS ASSOCIATED WITH DECREMENTS IN EXPRESSION OF THE ALPHA1 GABA(A) RECEPTOR SUBUNIT, INDICATIVE OF FURTHER IMPAIRED PHASIC INHIBITION. THESE PHENOMENA OCCURRED IRRESPECTIVE OF NEURON PROJECTION DESTINATION AND SEX. BASED ON PREVIOUS OBSERVATIONS BY OUR LABORATORY OF AN EPIGENETIC MECHANISM FOR ETOH-INDUCED CHANGES IN CORTICAL GABA(A) RECEPTOR SUBUNIT EXPRESSION, THE HISTONE DEACETYLASE INHIBITOR TRICHOSTATIN A WAS ADMINISTERED TO WATER- AND ETOH-EXPOSED ANIMALS, AND PREVENTED ETOH-INDUCED CHANGES IN SPONTANEOUS IPSC FREQUENCY, IPSC DECAY KINETICS, AND GABA(A) RECEPTOR SUBUNIT EXPRESSION. CONCLUSIONS: TAKEN TOGETHER, THESE RESULTS DEMONSTRATE THAT CHRONIC ETOH EXPOSURE IMPAIRS SYNAPTIC INHIBITORY NEUROTRANSMISSION IN DEEP-LAYER PYRAMIDAL NEURONS OF THE MEDIAL PFC IN BOTH MALE AND FEMALE RATS. THESE MALADAPTATIONS OCCUR IN NEURONS PROJECTING TO NUMEROUS REGIONS IMPLICATED IN THE SEQUELAE OF ETOH DEPENDENCE, OFFERING A MECHANISTIC LINK BETWEEN THE MANIFESTATION OF PFC DYSFUNCTION AND NEGATIVE AFFECTIVE STATES OBSERVED WITH EXTENDED CONSUMPTION. 2019 9 4498 28 MORPHINE REGULATES ARGONAUTE 2 AND TH EXPRESSION AND ACTIVITY BUT NOT MIR-133B IN MIDBRAIN DOPAMINERGIC NEURONS. EPIGENETIC CHANGES SUCH AS MICRORNAS (MIRS)/AGO2-INDUCED GENE SILENCING REPRESENT COMPLEX MOLECULAR SIGNATURE THAT REGULATE CELLULAR PLASTICITY. RECENT STUDIES SHOWED INVOLVEMENT OF MIRS AND AGO2 IN DRUG ADDICTION. IN THIS STUDY, WE SHOW THAT CHANGES IN GENE EXPRESSION INDUCED BY MORPHINE AND MORPHINE WITHDRAWAL OCCUR WITH CONCOMITANT EPIGENETIC MODIFICATIONS IN THE MESOLIMBIC DOPAMINERGIC (DA) PATHWAY [VENTRAL TEGMENTAL AREA (VTA)/NUCLEUS ACCUMBENS (NAC) SHELL], WHICH IS CRITICALLY INVOLVED IN DRUG-INDUCED DEPENDENCE. WE FOUND THAT ACUTE OR CHRONIC MORPHINE ADMINISTRATION AS WELL AS MORPHINE WITHDRAWAL DID NOT MODIFY MIR-133B MESSENGER RNA (MRNA) EXPRESSION IN THE VTA, WHEREAS AGO2 PROTEIN LEVELS WERE DECREASED AND INCREASED IN MORPHINE-DEPENDENT RATS AND AFTER MORPHINE WITHDRAWAL, RESPECTIVELY. THESE CHANGES WERE PARALLELED WITH ENHANCED AND DECREASED NAC TYROSINE HYDROXYLASE (TH) PROTEIN (AN EARLY DA MARKER) IN MORPHINE-DEPENDENT RATS AND AFTER WITHDRAWAL, RESPECTIVELY. WE ALSO OBSERVED CHANGES IN TH MRNA EXPRESSION IN THE VTA THAT COULD BE RELATED TO AGO2-INDUCED TRANSLATIONAL REPRESSION OF TH MRNA DURING MORPHINE WITHDRAWAL. HOWEVER, THE VTA NUMBER OF TH-POSITIVE NEURONS SUFFERED NO ALTERATIONS AFTER THE DIFFERENT TREATMENT. ACUTE MORPHINE ADMINISTRATION PRODUCED A MARKED INCREASE IN TH ACTIVITY AND DA TURNOVER IN THE NAC (SHELL). IN CONTRAST, PRECIPITATED MORPHINE WITHDRAWAL DECREASED TH ACTIVATION AND DID NOT CHANGE DA TURNOVER. THESE FINDINGS PROVIDE NEW INFORMATION INTO THE POSSIBLE CORRELATION BETWEEN AGO2/MIRS COMPLEX REGULATION AND DA NEURONS PLASTICITY DURING OPIATE ADDICTION. 2015 10 4418 23 MOLECULAR AND EPIGENETIC ASPECTS OF OPIOID RECEPTORS IN DRUG ADDICTION AND PAIN MANAGEMENT IN SPORT. OPIOIDS ARE SUBSTANCES DERIVED FROM OPIUM (NATURAL OPIOIDS). IN ITS RAW STATE, OPIUM IS A GUMMY LATEX EXTRACTED FROM PAPAVER SOMNIFERUM. THE USE OF OPIOIDS AND THEIR NEGATIVE HEALTH CONSEQUENCES AMONG PEOPLE WHO USE DRUGS HAVE BEEN STUDIED. TODAY, OPIOIDS ARE STILL THE MOST COMMONLY USED AND EFFECTIVE ANALGESIC TREATMENTS FOR SEVERE PAIN, BUT THEIR USE AND ABUSE CAUSES DETRIMENTAL SIDE EFFECTS FOR HEALTH, INCLUDING ADDICTION, THUS IMPACTING THE USER'S QUALITY OF LIFE AND CAUSING OVERDOSE. THE MESOCORTICOLIMBIC DOPAMINERGIC CIRCUITRY REPRESENTS THE BRAIN CIRCUIT MEDIATING BOTH NATURAL REWARDS AND THE REWARDING ASPECTS OF NEARLY ALL DRUGS OF ABUSE, INCLUDING OPIOIDS. HENCE, UNDERSTANDING HOW OPIOIDS AFFECT THE FUNCTION OF DOPAMINERGIC CIRCUITRY MAY BE USEFUL FOR BETTER KNOWLEDGE OF THE PROCESS AND TO DEVELOP EFFECTIVE THERAPEUTIC STRATEGIES IN ADDICTION. THE AIM OF THIS REVIEW WAS TO SUMMARIZE THE MAIN FEATURES OF OPIOIDS AND OPIOID RECEPTORS AND FOCUS ON THE MOLECULAR AND UPCOMING EPIGENETIC MECHANISMS LEADING TO OPIOID ADDICTION. SINCE SYNTHETIC OPIOIDS CAN BE EFFECTIVE FOR PAIN MANAGEMENT, THEIR ABILITY TO INDUCE ADDICTION IN ATHLETES, WITH THE RISK OF INCURRING DOPING, IS ALSO DISCUSSED. 2023 11 1706 29 DYNORPHIN/KOP AND NOCICEPTIN/NOP GENE EXPRESSION AND EPIGENETIC CHANGES BY COCAINE IN RAT STRIATUM AND NUCLEUS ACCUMBENS. COCAINE INDUCES NEUROCHEMICAL CHANGES OF ENDOGENOUS PRODYNORPHIN-KAPPA OPIOID RECEPTOR (PDYN-KOP) AND PRONOCICEPTIN/ORPHANINFQ-NOCICEPTIN RECEPTOR (PN/OFQ-NOP) SYSTEMS. BOTH SYSTEMS PLAY AN IMPORTANT ROLE IN REWARDING MECHANISMS AND ADDICTIVE STIMULUS PROCESSING BY MODULATING DRUG-INDUCED DOPAMINERGIC ACTIVATION IN THE MESOCORTICO-LIMBIC BRAIN AREAS. THEY ARE ALSO INVOLVED IN REGULATING STRESS MECHANISMS RELATED TO ADDICTION. THE AIM OF THIS STUDY WAS TO INVESTIGATE POSSIBLE CHANGES OF GENE EXPRESSION OF THE DYNORPHINERGIC AND NOCICEPTINERGIC SYSTEM COMPONENTS IN THE NUCLEUS ACCUMBENS (NA) AND IN MEDIAL AND LATERAL CAUDATE PUTAMEN (MCPU AND LCPU, RESPECTIVELY) OF RATS, FOLLOWING CHRONIC SUBCUTANEOUS INFUSION OF COCAINE. IN ADDITION, THE EPIGENETIC HISTONE MODIFICATIONS H3K4ME3 AND H3K27ME3 (AN ACTIVATING AND A REPRESSIVE MARKER, RESPECTIVELY) AT THE PROMOTER LEVEL OF THE PDYN, KOP, PN/OFQ AND NOP GENES WERE INVESTIGATED. RESULTS SHOWED THAT COCAINE INDUCED PDYN GENE EXPRESSION UP-REGULATION IN THE NA AND LCPU, AND ITS DOWN-REGULATION IN THE MCPU, WHEREAS KOP MRNA LEVELS WERE UNCHANGED. MOREOVER, COCAINE EXPOSURE DECREASED PN/OFQ GENE EXPRESSION IN THE NA AND LCPU, WHILE NOP MRNA LEVELS APPEARED SIGNIFICANTLY INCREASED IN THE NA AND DECREASED IN THE LCPU. SPECIFIC CHANGES OF THE H3K4ME3 AND H3K27ME3 LEVELS WERE FOUND AT PDYN, PN/OFQ, AND NOP GENE PROMOTER, CONSISTENT WITH THE OBSERVED GENE EXPRESSION ALTERATIONS. THE PRESENT FINDINGS CONTRIBUTE TO BETTER DEFINE THE ROLE OF ENDOGENOUS PDYN-KOP AND PN/OFQ-NOP SYSTEMS IN NEUROPLASTICITY MECHANISMS FOLLOWING CHRONIC COCAINE TREATMENT. THE EPIGENETIC HISTONE MODIFICATIONS UNDERLYING THE GENE EXPRESSION CHANGES LIKELY MEDIATE THE EFFECTS OF COCAINE ON TRANSCRIPTIONAL REGULATION OF SPECIFIC GENE PROMOTERS THAT RESULT IN LONG-LASTING DRUG-INDUCED PLASTICITY. 2014 12 6602 21 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 4850 30 OPIOIDS AND OPIOID RECEPTORS; UNDERSTANDING PHARMACOLOGICAL MECHANISMS AS A KEY TO THERAPEUTIC ADVANCES AND MITIGATION OF THE MISUSE CRISIS. OPIOIDS ARE A MAINSTAY IN ACUTE PAIN MANAGEMENT AND PRODUCE THEIR EFFECTS AND SIDE EFFECTS (E.G., TOLERANCE, OPIOID-USE DISORDER AND IMMUNE SUPPRESSION) BY INTERACTION WITH OPIOID RECEPTORS. I WILL DISCUSS OPIOID PHARMACOLOGY IN SOME CONTROVERSIAL AREAS OF ENQUIRY OF ANAESTHETIC RELEVANCE. THE MAIN OPIOID TARGET IS THE MICRO (MU,MOP) RECEPTOR BUT OTHER MEMBERS OF THE OPIOID RECEPTOR FAMILY, DELTA (DELTA; DOP) AND KAPPA (KAPPA; KOP) OPIOID RECEPTORS ALSO PRODUCE ANALGESIC ACTIONS. THESE ARE NALOXONE-SENSITIVE. THERE IS IMPORTANT CLINICAL DEVELOPMENT RELATING TO THE NOCICEPTIN/ORPHANIN FQ (NOP) RECEPTOR, AN OPIOID RECEPTOR THAT IS NOT NALOXONE-SENSITIVE. BETTER UNDERSTANDING OF THE DRIVERS FOR OPIOID EFFECTS AND SIDE EFFECTS MAY FACILITATE SEPARATION OF SIDE EFFECTS AND PRODUCTION OF SAFER DRUGS. OPIOIDS BIND TO THE RECEPTOR ORTHOSTERIC SITE TO PRODUCE THEIR EFFECTS AND CAN ENGAGE MONOMER OR HOMO-, HETERODIMER RECEPTORS. SOME LIGANDS CAN DRIVE ONE INTRACELLULAR PATHWAY OVER ANOTHER. THIS IS THE BASIS OF BIASED AGONISM (OR FUNCTIONAL SELECTIVITY). OPIOID ACTIONS AT THE ORTHOSTERIC SITE CAN BE MODULATED ALLOSTERICALLY AND POSITIVE ALLOSTERIC MODULATORS THAT ENHANCE OPIOID ACTION ARE IN DEVELOPMENT. AS WELL AS TARGETING LIGAND-RECEPTOR INTERACTION AND TRANSDUCTION, MODULATING RECEPTOR EXPRESSION AND HENCE FUNCTION IS ALSO TRACTABLE. THERE IS EVIDENCE FOR EPIGENETIC ASSOCIATIONS WITH DIFFERENT TYPES OF PAIN AND ALSO SUBSTANCE MISUSE. AS LONG AS THE OPIOID NARRATIVE IS DEFINED BY THE 'OPIOID CRISIS' THE DRIVE TO REMOVE THEM COULD GATHER PACE. THIS WILL DENY USE WHERE THEY ARE EFFECTIVE, AND ACCESS TO MORPHINE FOR PAIN RELIEF IN LOW INCOME COUNTRIES. 2023 14 2886 28 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 15 2705 33 EXERCISE AND LOW-LEVEL GABA(A) RECEPTOR INHIBITION MODULATE LOCOMOTOR ACTIVITY AND THE EXPRESSION OF BDNF ACCOMPANIED BY CHANGES IN EPIGENETIC REGULATION IN THE HIPPOCAMPUS. AEROBIC EXERCISE IS KNOWN TO INCREASE EXPRESSION OF BRAIN-DERIVED NEUROTROPHIC FACTOR (BDNF) IN THE HIPPOCAMPUS AND TO IMPROVE COGNITIVE FUNCTION. THE INHIBITION OF GABAERGIC SYNAPSES ENHANCES HIPPOCAMPAL PLASTICITY AS WELL AS LEARNING AND MEMORY. THE OBJECTIVE OF THE PRESENT STUDY WAS TO EXAMINE THE INTERACTIVE EFFECT OF LOW-LEVEL GABA(A) RECEPTOR INHIBITION AND EXERCISE ON BEHAVIOR TESTS (COGNITIVE FUNCTION AND LOCOMOTOR ACTIVITY), EXPRESSION OF BDNF AND EPIGENETIC REGULATIONS INCLUDING THE ACTIVITY LEVELS OF HISTONE ACETYLTRANSFERASES (HATS) AND HISTONE DEACETYLASES (HDACS) IN THE HIPPOCAMPUS. ICR MICE WERE DIVIDED INTO TWO GROUPS: THOSE WHO DID NOT PARTICIPATE IN EXERCISE AND THOSE WHO PARTICIPATED IN EXERCISE. EACH GROUP WAS SUBDIVIDED INTO TWO OTHER GROUPS: THE ONE WHO RECEIVED VEHICLE AND THE ONE WHO RECEIVED GABA(A) RECEPTOR ANTAGONIST, BICUCULLIN. WE ADMINISTERED SALINE OR BICUCULLINE INTRAPERITONEALLY TO THE MICE AT A NON-EPILEPTIC DOSE OF 0.25 MG/KG, WHEREAS THE MICE WERE EXERCISED ON A TREADMILL FOR APPROXIMATELY 1 H A DAY, 5 DAYS A WEEK FOR 4 WEEKS. NOVEL-OBJECT RECOGNITION TEST AND LOCOMOTOR ACTIVITY WERE ASSESSED AT A REST DAY APPROXIMATELY 4 DAYS BEFORE THE EUTHANASIA. THE MICE WERE EUTHANIZED 4 H AFTER THE LAST EXERCISE SESSION. AEROBIC EXERCISE FOR 4 WEEKS INCREASED MRNA AND PROTEIN EXPRESSION OF BDNF IN THE HIPPOCAMPUS, ACCOMPANIED BY ENHANCED HAT ACTIVITY. ALTERNATIVELY, BICUCULLINE ADMINISTRATION INCREASED HDAC ACTIVITY IN THE HIPPOCAMPUS. FURTHERMORE, EXERCISE IN THE PRESENCE OF BICUCULLINE ADMINISTRATION INCREASED LOCOMOTOR ACTIVITY, INDICATING THAT EXERCISE COMBINED WITH LOW-LEVEL GABA(A) RECEPTOR INHIBITION POTENTIATED THE ACTIVITY OF THE MICE. ALTOGETHER, THE PRESENT STUDY SUGGESTED THAT EXERCISE BENEFICIALLY CONTRIBUTES TO NEUROPROTECTION IN THE HIPPOCAMPUS ACCOMPANIED BY THE UP-REGULATION OF BDNF EXPRESSION AND EPIGENETIC REGULATION, WHEREAS THE CHRONIC INHIBITION OF GABA(A) RECEPTOR POTENTIATES EXERCISE-INDUCED BEHAVIORAL ACTIVITY. 2018 16 4469 22 MOLECULAR NEUROLOGICAL CORRELATES OF ENDORPHINERGIC/DOPAMINERGIC MECHANISMS IN REWARD CIRCUITRY LINKED TO ENDORPHINERGIC DEFICIENCY SYNDROME (EDS). THE CONSENSUS OF THE CURRENT LITERATURE STRONGLY SUPPORTS THE CONCEPT THAT BRAIN NEUROTRANSMITTERS, AND SECOND MESSENGERS INVOLVED IN THE NET RELEASE OF DOPAMINE IN THE MESOLIMBIC REGION, ESPECIALLY THE NUCLEUS ACCUMBENS (NAC), IS DIRECTLY LINKED TO MOTIVATION, ANTI-STRESS, INCENTIVE SALIENCE (WANTING), AND WELL-BEING. THE ROLE OF DOPAMINE IN TERMS OF ALCOHOL WITHDRAWAL SYMPTOMOLOGY, COCAINE CRAVING BEHAVIOR, DOPAMINE -CONDENSATION PRODUCTS (TIQS), AND MORE RECENTLY, THE GENETIC ASPECTS OF DRUG-SEEKING AND PRO-DOPAMINE REGULATION, PROVIDE COMPELLING EVIDENCE OF THE RELEVANT MOLECULAR NEUROLOGICAL CORRELATES OF DOPAMINERGIC /ENDORPHINERGIC MECHANISMS IN REWARD CIRCUITRY DUE TO GENETIC POLYMORPHISMS AND EPIGENETIC INSULTS. IN THE FACE OF AN AMERICANS OPIOID EPIDEMIC, THE CLINICAL CONSENSUS IS TO TREAT OPIOID USE DISORDER (OUD) WITH LIFE-LONG OPIOID SUBSTITUTION THERAPY. HOWEVER, THE AUTHORS SUGGEST A PARADIGM SHIFT INVOLVING NOVEL MODALITIES LIKE TARGETING THE ENDORPHINERGIC SYSTEM LINKED TO DOPAMINE RELEASE AT THE NAC, IN TERMS OF THE INDUCTION OF REQUIRED "DOPAMINE HOMEOSTASIS." UTILIZING THE KNOWN GENETIC - ENVIRONMENTAL INTERACTION THEOREM P = G +E, THE AUTHORS PROVIDE A CLEAR RATIONALE FOR THE ADOPTION OF GENETIC RISK TESTING COUPLED WITH ENDORPHINERGIC/DOPAMINE REGULATION TO ADDRESS DYSFUNCTION ACROSS THE BRAIN REWARD CIRCUITRY. THE GOAL OF ALTERING RESTING-STATE, FUNCTIONAL CONNECTIVITY MAY REQUIRE A GENTLE "NEUROTRANSMITTER FIX" VIS ENKEPHALINASE INHIBITION TO OVERCOME OR COMBAT - SELF-INDUCTION OF ACUTE DOPAMINE RELEASE VIA PSYCHOACTIVE SUBSTANCE MISUSE RESULTING IN CHRONIC DOPAMINE DOWN-REGULATION. AS SUBSETS OF REWARD DEFICIENCY, WE ARE POISED TO PROVIDE NOVEL, GENETICALLY GUIDED THERAPY FOR ENDORPHINERGIC, OPIOIDERGIC, AND DOPAMINERGIC DEFICIENCIES AND RELATED SYNDROMES, UTILIZING "PRECISION ADDICTION MANAGEMENT. 2020 17 2012 24 EPIGENETIC BASIS OF OPIATE SUPPRESSION OF BDNF GENE EXPRESSION IN THE VENTRAL TEGMENTAL AREA. BRAIN-DERIVED NEUROTROPHIC FACTOR (BDNF) HAS A CRUCIAL ROLE IN MODULATING NEURAL AND BEHAVIORAL PLASTICITY TO DRUGS OF ABUSE. WE FOUND A PERSISTENT DOWNREGULATION OF EXON-SPECIFIC BDNF EXPRESSION IN THE VENTRAL TEGMENTAL AREA (VTA) IN RESPONSE TO CHRONIC OPIATE EXPOSURE, WHICH WAS MEDIATED BY SPECIFIC EPIGENETIC MODIFICATIONS AT THE CORRESPONDING BDNF GENE PROMOTERS. EXPOSURE TO CHRONIC MORPHINE INCREASED STALLING OF RNA POLYMERASE II AT THESE BDNF PROMOTERS IN VTA AND ALTERED PERMISSIVE AND REPRESSIVE HISTONE MODIFICATIONS AND OCCUPANCY OF THEIR REGULATORY PROTEINS AT THE SPECIFIC PROMOTERS. FURTHERMORE, WE FOUND THAT MORPHINE SUPPRESSED BINDING OF PHOSPHO-CREB (CAMP RESPONSE ELEMENT BINDING PROTEIN) TO BDNF PROMOTERS IN VTA, WHICH RESULTED FROM ENRICHMENT OF TRIMETHYLATED H3K27 AT THE PROMOTERS, AND THAT DECREASED NURR1 (NUCLEAR RECEPTOR RELATED-1) EXPRESSION ALSO CONTRIBUTED TO BDNF REPRESSION AND ASSOCIATED BEHAVIORAL PLASTICITY TO MORPHINE. OUR FINDINGS SUGGEST PREVIOUSLY UNKNOWN EPIGENETIC MECHANISMS OF MORPHINE-INDUCED MOLECULAR AND BEHAVIORAL NEUROADAPTATIONS. 2015 18 2841 28 FREQUENCY OF THE DOPAMINE RECEPTOR D3 (RS6280) VS. OPIOID RECEPTOR MICRO1 (RS1799971) POLYMORPHIC RISK ALLELES IN PATIENTS WITH OPIOID USE DISORDER: A PREPONDERANCE OF DOPAMINERGIC MECHANISMS? WHILE OPIOIDS ARE A POWERFUL CLASS OF DRUGS THAT INHIBIT TRANSMISSION OF PAIN SIGNALS, THEIR USE IS TARNISHED BY THE CURRENT EPIDEMIC OF OPIOID USE DISORDER (OUD) AND OVERDOSE DEATHS. NOTWITHSTANDING PUBLISHED REPORTS, THERE REMAIN GAPS IN OUR KNOWLEDGE OF OPIOID RECEPTOR MECHANISMS AND THEIR ROLE IN OPIOID SEEKING BEHAVIOR. THUS, NOVEL INSIGHTS INTO MOLECULAR, NEUROGENETIC AND NEUROPHARMACOLOGICAL BASES OF OUD ARE NEEDED. WE PROPOSE THAT AN ADDICTIVE ENDOPHENOTYPE MAY NOT BE ENTIRELY SPECIFIC TO THE DRUG OF CHOICE BUT RATHER MAY BE GENERALIZABLE TO ALTERED BRAIN REWARD CIRCUITS IMPACTING NET MESOCORTICOLIMBIC DOPAMINE RELEASE. WE SUGGEST THAT GENETIC OR EPIGENETIC ALTERATIONS ACROSS DOPAMINERGIC REWARD SYSTEMS LEAD TO UNCONTROLLABLE SELF-ADMINISTRATION OF OPIOIDS AND OTHER DRUGS. FOR INSTANCE, DIMINISHED AVAILABILITY VIA KNOCKOUT OF DOPAMINE D3 RECEPTOR (DRD3) INCREASES VULNERABILITY TO OPIOIDS. BUILDING UPON THIS CONCEPT VIA THE USE OF A SOPHISTICATED POLYMORPHIC RISK ANALYSIS IN A HUMAN COHORT OF CHRONIC OPIOID USERS, WE FOUND EVIDENCE FOR A HIGHER FREQUENCY OF POLYMORPHIC DRD3 RISK ALLELE (RS6280) THAN OPIOID RECEPTOR MICRO1 (RS1799971). IN CONCLUSION, WHILE OPIOIDERGIC MECHANISMS ARE INVOLVED IN OUD, DOPAMINE-RELATED RECEPTORS MAY HAVE PRIMARY INFLUENCE ON OPIOID-SEEKING BEHAVIOR IN AFRICAN AMERICANS. THESE FINDINGS SUGGEST OUD-TARGETED NOVEL AND IMPROVED NEUROPHARMACOLOGICAL THERAPIES MAY REQUIRE FOCUS ON DRD3-MEDIATED REGULATION OF DOPAMINERGIC HOMEOSTASIS. 2022 19 2670 26 ETHANOL ACTIONS ON THE VENTRAL TEGMENTAL AREA: NOVEL POTENTIAL TARGETS ON REWARD PATHWAY NEURONS. THE VENTRAL TEGMENTAL AREA (VTA) EVALUATES SALIENCE OF ENVIRONMENTAL STIMULI AND PROVIDES DOPAMINERGIC INNERVATION TO MANY BRAIN AREAS AFFECTED BY ACUTE AND CHRONIC ETHANOL EXPOSURE. WHILE PRIMARILY ASSOCIATED WITH REWARDING AND REINFORCING STIMULI, RECENT EVIDENCE INDICATES A ROLE FOR THE VTA IN AVERSION AS WELL. ETHANOL ACTIONS IN THE VTA MAY TRIGGER NEUROADAPTATION RESULTING IN REDUCTION OF THE AVERSIVE RESPONSES TO ALCOHOL AND A RELATIVE INCREASE IN THE REWARDING RESPONSES. IN SEARCHING FOR EFFECTIVE PHARMACOTHERAPIES FOR THE TREATMENT OF ALCOHOL ABUSE AND ALCOHOLISM, RECOGNITION OF THIS IMBALANCE MAY REVEAL NOVEL STRATEGIES. IN ADDITION TO CONVENTIONAL RECEPTOR/ION CHANNEL PHARMACOTHERAPIES, EPIGENETIC FACTORS THAT CONTROL NEUROADAPTATION TO CHRONIC ETHANOL TREATMENT CAN BE TARGETED AS AN AVENUE FOR DEVELOPMENT OF THERAPEUTIC APPROACHES TO RESTORE THE BALANCE. FURTHERMORE, WHEN EXPLORING THERAPIES TO ADDRESS REWARD/AVERSION IMBALANCE IN THE ACTION OF ALCOHOL IN THE VTA, SEX DIFFERENCES HAVE TO BE TAKEN INTO ACCOUNT TO ENSURE EFFECTIVE TREATMENT FOR BOTH MEN AND WOMEN. THESE PRINCIPLES APPLY TO A VTA-CENTRIC APPROACH TO THERAPIES, BUT SHOULD HOLD TRUE WHEN THINKING ABOUT THE OVERALL APPROACH IN THE DEVELOPMENT OF NEUROACTIVE DRUGS TO TREAT ALCOHOL USE DISORDERS. ALTHOUGH THE FUNCTIONS OF THE VTA ITSELF ARE COMPLEX, IT IS A USEFUL MODEL SYSTEM TO EVALUATE THE REWARD/AVERSION IMBALANCE THAT OCCURS WITH ETHANOL EXPOSURE AND COULD BE USED TO PROVIDE NEW LEADS IN THE EFFORTS TO DEVELOP NOVEL DRUGS TO TREAT ALCOHOLISM. 2018 20 1330 33 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