1 5541 112 ROLE OF DIETARY PHENOLS IN MITIGATING MICROGLIA-MEDIATED NEUROINFLAMMATION. CHRONIC NEUROINFLAMMATION IS A PATHOLOGICAL FEATURE OF A NUMBER OF CENTRAL NERVOUS SYSTEM (CNS) DISEASES AND IS MEDIATED BY SUSTAINED ACTIVATION OF MICROGLIAL CELLS, THE INNATE IMMUNE CELLS OF THE CNS. STUDIES HAVE MAINLY FOCUSED ON IDENTIFYING THE MOLECULAR AND EPIGENETIC MECHANISMS OF MICROGLIAL ACTIVATION. THIS IS CRUCIAL IN DESIGNING THERAPEUTIC STRATEGIES FOR NEUROPATHOLOGIES IN WHICH PROLONGED MICROGLIAL ACTIVATION IS KNOWN TO EXACERBATE DISEASE CONDITION. IN RECENT YEARS, INCREASING EVIDENCE SHOW THAT NATURALLY OCCURRING COMPOUNDS PRESENT IN REGULAR DIET COULD FUNCTION AS "NUTRACEUTICALS," ARRESTING MICROGLIAL ACTIVATION, AND THUS CONFERRING NEUROPROTECTION. THIS REVIEW SUMMARIZES OUR UNDERSTANDING OF THE ROLE OF DIETARY PHENOLIC NUTRACEUTICALS IN MITIGATING MICROGLIA-MEDIATED NEUROINFLAMMATION. STUDIES SHOW THAT THESE NATURAL PHENOLS INHIBIT KEY SIGNALING PATHWAYS IN ACTIVATED MICROGLIA SUCH AS THE NFKAPPAB, MAPK AND JAK-STAT THAT TRIGGER MICROGLIA-MEDIATED INFLAMMATION IN VARIOUS NEUROPATHOLOGICAL CONDITIONS SUCH AS INJURY, INFECTION, STROKE, AUTISM AND NEURODEGENERATIVE DISEASES, I.E., ALZHEIMER'S DISEASE AND PARKINSON'S DISEASE. THE ANTI-INFLAMMATORY AND ANTIOXIDANT EFFECT EXERTED BY THESE NATURAL PHENOLS HAVE SHOWN CONSIDERABLE SUCCESS IN IMPROVING DISEASE CONDITION IN ANIMAL MODELS OF NEUROPATHOLOGIES, AND THUS SEEM TO BE SUITABLE CANDIDATES FOR DEVELOPING THERAPEUTIC STRATEGIES. 2016 2 4149 31 MECHANISTIC INSIGHT INTO THE EFFECTS OF CURCUMIN ON NEUROINFLAMMATION-DRIVEN CHRONIC PAIN. CHRONIC PAIN IS A PERSISTENT AND UNREMITTING CONDITION THAT HAS IMMENSE EFFECTS ON PATIENTS' QUALITY OF LIFE. STUDIES HAVE SHOWN THAT NEUROINFLAMMATION IS ASSOCIATED WITH THE INDUCTION AND PROGRESSION OF CHRONIC PAIN. THE ACTIVATION OF MICROGLIA AND ASTROCYTES IS THE MAJOR HALLMARK OF SPINAL NEUROINFLAMMATION LEADING TO NEURONAL EXCITABILITY IN THE PROJECTION NEURONS. EXCESSIVE ACTIVATION OF MICROGLIA AND ASTROCYTES IS ONE OF THE MAJOR CONTRIBUTING FACTORS TO THE EXACERBATION OF PAIN. HOWEVER, THE CURRENT CHRONIC PAIN TREATMENTS, MAINLY BY TARGETING THE NEURONAL CELLS, REMAIN INEFFECTIVE AND UNABLE TO MEET THE PATIENTS' NEEDS. CURCUMIN, A NATURAL PLANT PRODUCT FOUND IN THE CURCUMA GENUS, IMPROVES CHRONIC PAIN BY DIMINISHING THE RELEASE OF INFLAMMATORY MEDIATORS FROM THE SPINAL GLIA. THIS REVIEW DETAILS THE ROLE OF CURCUMIN IN MICROGLIA AND ASTROCYTES BOTH IN VITRO AND IN VIVO AND HOW IT IMPROVES PAIN. WE ALSO DESCRIBE THE MECHANISM OF CURCUMIN BY HIGHLIGHTING THE MAJOR GLIA-MEDIATED CASCADES IN PAIN. MOREOVER, THE ROLE OF CURCUMIN ON INFLAMMASOME AND EPIGENETIC REGULATION IS DISCUSSED. FURTHERMORE, WE DISCUSS THE STRATEGIES USED TO IMPROVE THE EFFICACY OF CURCUMIN. THIS REVIEW ILLUSTRATES THAT CURCUMIN MODULATING MICROGLIA AND ASTROCYTES COULD ASSURE THE TREATMENT OF CHRONIC PAIN BY SUPPRESSING SPINAL NEUROINFLAMMATION. 2021 3 4333 43 MICRORNAS: KEY PLAYERS IN MICROGLIA AND ASTROCYTE MEDIATED INFLAMMATION IN CNS PATHOLOGIES. THE SIGNIFICANCE OF MICROGLIA AND ASTROCYTES IN NEURAL DEVELOPMENT, IN MAINTAINING SYNAPTIC CONNECTIONS AND HOMEOSTASIS IN THE HEALTHY BRAIN IS WELL ESTABLISHED. MICROGLIA ARE DYNAMIC IMMUNE CELLS OF THE BRAIN THAT ELICIT AN IMMUNE RESPONSE DURING BRAIN DAMAGE AND ALSO PARTICIPATE IN TISSUE REPAIR AND REGENERATION, WHILE ASTROCYTES CONTRIBUTE TO THE LOCAL INFLAMMATORY RESPONSE BY PRODUCING PROINFLAMMATORY CYTOKINES AND RESOLVING NEURONAL DAMAGE THROUGH PRODUCTION OF ANTI-INFLAMMATORY CYTOKINES AND NEUROTROPHIC FACTORS. RECENT EFFORTS HAVE FOCUSED ON ELUCIDATING THE EPIGENETIC MECHANISMS WHICH REGULATE GLIAL CELL BEHAVIOR IN NORMAL AND PATHOLOGIC STATES. AN IMPORTANT CLASS OF EPIGENETIC REGULATORS IS MICRORNAS (MIRNAS) WHICH ARE SMALL NON-CODING RNA MOLECULES THAT REGULATE GENE EXPRESSION POSTTRANSCRIPTIONALLY. CERTAIN DYSREGULATED MIRNAS CONTRIBUTE TO CHRONIC MICROGLIAL INFLAMMATION IN THE BRAIN, THEREBY LEADING TO PROGRESSION OF NEUROLOGICAL DISEASES LIKE ALZHEIMER'S DISEASE, TRAUMATIC INJURY, AMYOTROPHIC LATERAL SCLEROSIS AND STROKE. FURTHER, SEVERAL MIRNAS ARE DIFFERENTIALLY EXPRESSED IN ASTROCYTES AFTER ISCHEMIA AND SPINAL CORD INJURY. DESPITE KNOWLEDGE ABOUT MIRNAS IN NEUROINFLAMMATION, LITTLE IS KNOWN ABOUT EFFECTIVE DELIVERY ROUTES AND PHARMACOKINETIC DATA FOR MIRNA BASED THERAPEUTICS. THIS REVIEW SUMMARIZES THE CURRENT RESEARCH ON THE ROLE OF MIRNAS IN PROMOTING AND INHIBITING INFLAMMATORY RESPONSE OF MICROGLIA AND ASTROCYTES IN A DISEASE-SPECIFIC MANNER. IN ADDITION, MIRNA DELIVERY AS A THERAPEUTIC STRATEGY TO TREAT NEUROINFLAMMATION IS DISCUSSED. 2016 4 2350 37 EPIGENETIC REGULATION OF NEUROINFLAMMATION IN PARKINSON'S DISEASE. NEUROINFLAMMATION IS ONE OF THE MOST SIGNIFICANT FACTORS INVOLVED IN THE INITIATION AND PROGRESSION OF PARKINSON'S DISEASE. PD IS A NEURODEGENERATIVE DISORDER WITH A MOTOR DISABILITY LINKED WITH VARIOUS COMPLEX AND DIVERSIFIED RISK FACTORS. THESE FACTORS TRIGGER MYRIADS OF CELLULAR AND MOLECULAR PROCESSES, SUCH AS MISFOLDING DEFECTIVE PROTEINS, OXIDATIVE STRESS, MITOCHONDRIAL DYSFUNCTION, AND NEUROTOXIC SUBSTANCES THAT INDUCE SELECTIVE NEURODEGENERATION OF DOPAMINE NEURONS. THIS NEURONAL DAMAGE ACTIVATES THE NEURONAL IMMUNE SYSTEM, INCLUDING GLIAL CELLS AND INFLAMMATORY CYTOKINES, TO TRIGGER NEUROINFLAMMATION. THE TRANSITION OF ACUTE TO CHRONIC NEUROINFLAMMATION ENHANCES THE SUSCEPTIBILITY OF INFLAMMATION-INDUCED DOPAMINERGIC NEURON DAMAGE, FORMING A VICIOUS CYCLE AND PROMPTING AN INDIVIDUAL TO PD DEVELOPMENT. EPIGENETIC MECHANISMS RECENTLY HAVE BEEN AT THE FOREFRONT OF THE REGULATION OF NEUROINFLAMMATORY FACTORS IN PD, PROPOSING A NEW DAWN FOR BREAKING THIS VICIOUS CYCLE. THIS REVIEW EXAMINED THE CORE EPIGENETIC MECHANISMS INVOLVED IN THE ACTIVATION AND PHENOTYPIC TRANSFORMATION OF GLIAL CELLS MEDIATED NEUROINFLAMMATION IN PD. WE FOUND THAT EPIGENETIC MECHANISMS DO NOT WORK INDEPENDENTLY, DESPITE BEING COORDINATED WITH EACH OTHER TO ACTIVATE NEUROINFLAMMATORY PATHWAYS. IN THIS REGARD, WE ATTEMPTED TO FIND THE SYNERGIC CORRELATION AND CONTRIBUTION OF THESE EPIGENETIC MODIFICATIONS WITH VARIOUS NEUROINFLAMMATORY PATHWAYS TO BROADEN THE CANVAS OF UNDERLYING PATHOLOGICAL MECHANISMS INVOLVED IN PD DEVELOPMENT. MOREOVER, THIS STUDY HIGHLIGHTED THE DUAL CHARACTERISTICS (NEUROPROTECTIVE/NEUROTOXIC) OF THESE EPIGENETIC MARKS, WHICH MAY COUNTERACT PD PATHOGENESIS AND MAKE THEM POTENTIAL CANDIDATES FOR DEVISING FUTURE PD DIAGNOSIS AND TREATMENT. 2021 5 6347 27 THE ROLE OF EPIGENETICS IN NEUROINFLAMMATORY-DRIVEN DISEASES. NEURODEGENERATIVE DISORDERS ARE CHARACTERIZED BY THE PROGRESSIVE LOSS OF CENTRAL AND/OR PERIPHERAL NERVOUS SYSTEM NEURONS. WITHIN THIS CONTEXT, NEUROINFLAMMATION COMES UP AS ONE OF THE MAIN FACTORS LINKED TO NEURODEGENERATION PROGRESSION. IN FACT, NEUROINFLAMMATION HAS BEEN RECOGNIZED AS AN OUTSTANDING FACTOR FOR ALZHEIMER'S DISEASE (AD), AMYOTROPHIC LATERAL SCLEROSIS (ALS), PARKINSON'S DISEASE (PD), AND MULTIPLE SCLEROSIS (MS). INTERESTINGLY, NEUROINFLAMMATORY DISEASES ARE CHARACTERIZED BY DRAMATIC CHANGES IN THE EPIGENETIC PROFILE, WHICH MIGHT PROVIDE NOVEL PROGNOSTIC AND THERAPEUTIC FACTORS TOWARDS NEUROINFLAMMATORY TREATMENT. DEEP CHANGES IN DNA AND HISTONE METHYLATION, ALONG WITH HISTONE ACETYLATION AND ALTERED NON-CODING RNA EXPRESSION, HAVE BEEN REPORTED AT THE ONSET OF INFLAMMATORY DISEASES. THE AIM OF THIS WORK IS TO REVIEW THE CURRENT KNOWLEDGE ON THIS FIELD. 2022 6 6139 30 THE ETIOLOGICAL CONTRIBUTION OF GABAERGIC PLASTICITY TO THE PATHOGENESIS OF NEUROPATHIC PAIN. NEUROPATHIC PAIN DEVELOPING AFTER PERIPHERAL OR CENTRAL NERVE INJURY IS THE RESULT OF PATHOLOGICAL CHANGES GENERATED THROUGH COMPLEX MECHANISMS. DISRUPTION IN THE HOMEOSTASIS OF EXCITATORY AND INHIBITORY NEURONS WITHIN THE CENTRAL NERVOUS SYSTEM IS A CRUCIAL FACTOR IN THE FORMATION OF HYPERALGESIA OR ALLODYNIA OCCURRING WITH NEUROPATHIC PAIN. THE CENTRAL GABAERGIC PATHWAY HAS RECEIVED ATTENTION FOR ITS EXTENSIVE DISTRIBUTION AND FUNCTION IN NEURAL CIRCUITS, INCLUDING THE GENERATION AND DEVELOPMENT OF NEUROPATHIC PAIN. GABAERGIC INHIBITORY CHANGES THAT OCCUR IN THE INTERNEURONS ALONG DESCENDING MODULATORY AND NOCICEPTIVE PATHWAYS IN THE CENTRAL NERVOUS SYSTEM ARE BELIEVED TO GENERATE NEURONAL PLASTICITY, SUCH AS SYNAPTIC PLASTICITY OR FUNCTIONAL PLASTICITY OF THE RELATED GENES OR PROTEINS, THAT IS THE FOUNDATION OF PERSISTENT NEUROPATHIC PAIN. THE PRIMARY GABAERGIC PLASTICITY OBSERVED IN NEUROPATHIC PAIN INCLUDES GABAERGIC SYNAPSE HOMO- AND HETEROSYNAPTIC PLASTICITY, DECREASED SYNTHESIS OF GABA, DOWN-EXPRESSION OF GLUTAMIC ACID DECARBOXYLASE AND GABA TRANSPORTER, ABNORMAL EXPRESSION OF NKCC1 OR KCC2, AND DISTURBED FUNCTION OF GABA RECEPTORS. IN THIS REVIEW, WE DESCRIBE POSSIBLE MECHANISMS ASSOCIATED WITH GABAERGIC PLASTICITY, SUCH AS CENTRAL SENSITIZATION AND GABAERGIC INTERNEURON APOPTOSIS, AND THE EPIGENETIC ETIOLOGIES OF GABAERGIC PLASTICITY IN NEUROPATHIC PAIN. MOREOVER, WE SUMMARIZE POTENTIAL THERAPEUTIC TARGETS OF GABAERGIC PLASTICITY THAT MAY ALLOW FOR SUCCESSFUL RELIEF OF HYPERALGESIA FROM NERVE INJURY. FINALLY, WE COMPARE THE EFFECTS OF THE GABAERGIC SYSTEM IN NEUROPATHIC PAIN TO OTHER TYPES OF CHRONIC PAIN TO UNDERSTAND THE CONTRIBUTION OF GABAERGIC PLASTICITY TO NEUROPATHIC PAIN. 2019 7 2214 40 EPIGENETIC MODIFICATIONS ASSOCIATED TO NEUROINFLAMMATION AND NEUROPATHIC PAIN AFTER NEURAL TRAUMA. ACCUMULATING EVIDENCE SUGGESTS THAT EPIGENETIC ALTERATIONS LIE BEHIND THE INDUCTION AND MAINTENANCE OF NEUROPATHIC PAIN. NEUROPATHIC PAIN IS USUALLY A CHRONIC CONDITION CAUSED BY A LESION, OR PATHOLOGICAL CHANGE, WITHIN THE NERVOUS SYSTEM. NEUROPATHIC PAIN APPEARS FREQUENTLY AFTER NERVE AND SPINAL CORD INJURIES OR DISEASES, PRODUCING A DEBILITATION OF THE PATIENT AND A DECREASE OF THE QUALITY OF LIFE. AT THE CELLULAR LEVEL, NEUROPATHIC PAIN IS THE RESULT OF NEURONAL PLASTICITY SHAPED BY AN INCREASE IN THE SENSITIVITY AND EXCITABILITY OF SENSORY NEURONS OF THE CENTRAL AND PERIPHERAL NERVOUS SYSTEM. ONE OF THE MECHANISMS THOUGHT TO CONTRIBUTE TO HYPEREXCITABILITY AND THEREFORE TO THE ONTOGENY OF NEUROPATHIC PAIN IS THE ALTERED EXPRESSION, TRAFFICKING, AND FUNCTIONING OF RECEPTORS AND ION CHANNELS EXPRESSED BY PRIMARY SENSORY NEURONS. BESIDES, NEURONAL AND GLIAL CELLS, SUCH AS MICROGLIA AND ASTROCYTES, TOGETHER WITH BLOOD BORNE MACROPHAGES, PLAY A CRITICAL ROLE IN THE INDUCTION AND MAINTENANCE OF NEUROPATHIC PAIN BY RELEASING POWERFUL NEUROMODULATORS SUCH AS PRO-INFLAMMATORY CYTOKINES AND CHEMOKINES, WHICH ENHANCE NEURONAL EXCITABILITY. ALTERED GENE EXPRESSION OF NEURONAL RECEPTORS, ION CHANNELS, AND PRO-INFLAMMATORY CYTOKINES AND CHEMOKINES, HAVE BEEN ASSOCIATED TO EPIGENETIC ADAPTATIONS OF THE INJURED TISSUE. WITHIN THIS REVIEW, WE DISCUSS THE INVOLVEMENT OF THESE EPIGENETIC CHANGES, INCLUDING HISTONE MODIFICATIONS, DNA METHYLATION, NON-CODING RNAS, AND ALTERATION OF CHROMATIN MODIFIERS, THAT HAVE BEEN SHOWN TO TRIGGER MODIFICATION OF NOCICEPTION AFTER NEURAL LESIONS. IN PARTICULAR, THE FUNCTION ON THESE PROCESSES OF EZH2, JMJD3, MECP2, SEVERAL HISTONE DEACETYLASES (HDACS) AND HISTONE ACETYL TRANSFERASES (HATS), G9A, DNMT, REST AND DIVERSE NON-CODING RNAS, ARE DESCRIBED. DESPITE THE EFFORT ON DEVELOPING NEW THERAPIES, CURRENT TREATMENTS HAVE ONLY PRODUCED LIMITED RELIEF OF THIS PAIN IN A PORTION OF PATIENTS. THUS, THE PRESENT REVIEW AIMS TO CONTRIBUTE TO FIND NOVEL TARGETS FOR CHRONIC NEUROPATHIC PAIN TREATMENT. 2018 8 5580 35 ROLE OF NEUROTOXICANTS IN THE PATHOGENESIS OF ALZHEIMER'S DISEASE: A MECHANISTIC INSIGHT. ALZHEIMER'S DISEASE (AD) IS THE MOST CONSPICUOUS CHRONIC NEURODEGENERATIVE SYNDROME, WHICH HAS BECOME A SIGNIFICANT CHALLENGE FOR THE GLOBAL HEALTHCARE SYSTEM. MULTIPLE STUDIES HAVE CORROBORATED A CLEAR ASSOCIATION OF NEUROTOXICANTS WITH AD PATHOGENICITY, SUCH AS AMYLOID BETA (ABETA) PROTEINS AND NEUROFIBRILLARY TANGLES (NFTS), SIGNALLING PATHWAY MODIFICATIONS, CELLULAR STRESS, COGNITIVE DYSFUNCTIONS, NEURONAL APOPTOSIS, NEUROINFLAMMATION, EPIGENETIC MODIFICATION, AND SO ON. THIS REVIEW, THEREFORE, AIMED TO ADDRESS SEVERAL ESSENTIAL MECHANISMS AND SIGNALLING CASCADES, INCLUDING WNT (WINGLESS AND INT.) SIGNALLING PATHWAY, AUTOPHAGY, MAMMALIAN TARGET OF RAPAMYCIN (MTOR), PROTEIN KINASE C (PKC) SIGNALLING CASCADES, CELLULAR REDOX STATUS, ENERGY METABOLISM, GLUTAMATERGIC NEUROTRANSMISSIONS, IMMUNE CELL STIMULATIONS (E.G. MICROGLIA, ASTROCYTES) AS WELL AS AN AMYLOID PRECURSOR PROTEIN (APP), PRESENILIN-1 (PSEN1), PRESENILIN-2 (PSEN2) AND OTHER AD-RELATED GENE EXPRESSIONS THAT HAVE BEEN PRETENTIOUS AND MODULATED BY THE VARIOUS NEUROTOXICANTS. THIS REVIEW CONCLUDED THAT NEUROTOXICANTS PLAY A MOMENTOUS ROLE IN DEVELOPING AD THROUGH MODULATING VARIOUS SIGNALLING CASCADES. NEVERTHELESS, COMPREHENSION OF THIS RISK AGENT-INDUCED NEUROTOXICITY IS FAR TOO LITTLE. MORE IN-DEPTH EPIDEMIOLOGICAL AND SYSTEMATIC INVESTIGATIONS ARE NEEDED TO UNDERSTAND THE POTENTIAL MECHANISMS BETTER TO ADDRESS THESE NEUROTOXICANTS AND IMPROVE APPROACHES TO THEIR RISK EXPOSURE THAT AID IN AD PATHOGENESIS.KEY MESSAGESINEVITABLE CASCADE MECHANISMS OF HOW ALZHEIMER'S DISEASE-RELATED (AD-RELATED) GENE EXPRESSIONS ARE MODULATED BY NEUROTOXICANTS HAVE BEEN DISCUSSED.INVOLVEMENT OF THE NEUROTOXICANTS-INDUCED PATHWAYS CAUSED AN EXTENDED RISK OF AD IS EXPLICITED.INTEGRATION OF CELL CULTURE, ANIMALS AND POPULATION-BASED ANALYSIS ON THE CLINICAL SEVERITY OF AD IS ADDRESSED. 2021 9 4969 36 PATHOLOGICAL NEUROINFLAMMATORY CONVERSION OF REACTIVE ASTROCYTES IS INDUCED BY MICROGLIA AND INVOLVES CHROMATIN REMODELING. FOLLOWING BRAIN INJURY OR IN NEURODEGENERATIVE DISEASES, ASTROCYTES BECOME REACTIVE AND MAY SUFFER PATHOLOGICAL REMODELING, FEATURES OF WHICH ARE THE LOSS OF THEIR HOMEOSTATIC FUNCTIONS AND A PRO-INFLAMMATORY GAIN OF FUNCTION THAT FACILITATES NEURODEGENERATION. PHARMACOLOGICAL INTERVENTION TO MODULATE THIS ASTROGLIAL RESPONSE AND NEUROINFLAMMATION IS AN INTERESTING NEW THERAPEUTIC RESEARCH STRATEGY, BUT IT STILL REQUIRES A DEEPER UNDERSTANDING OF THE UNDERLYING CELLULAR AND MOLECULAR MECHANISMS OF THE PHENOMENON. BASED ON THE KNOWN MICROGLIAL-ASTROGLIAL INTERACTION, THE PROMINENT ROLE OF THE NUCLEAR FACTOR KAPPA B (NF-KAPPAB) PATHWAY IN MEDIATING ASTROGLIAL PATHOLOGICAL PRO-INFLAMMATORY GAIN OF FUNCTION, AND ITS ABILITY TO RECRUIT CHROMATIN-REMODELING ENZYMES, WE FIRST EXPLORED THE MICROGLIAL ROLE IN THE INITIATION OF ASTROGLIAL PRO-INFLAMMATORY CONVERSION AND THEN MONITORED THE PROGRESSION OF EPIGENETIC CHANGES IN THE ASTROCYTIC CHROMATIN. DIFFERENT CONFIGURATIONS OF PRIMARY GLIAL CULTURE WERE USED TO MODULATE MICROGLIA-ASTROCYTE CROSSTALK WHILE INDUCING PRO-INFLAMMATORY GAIN OF FUNCTION BY LIPOPOLYSACCHARIDE (LPS) EXPOSURE. IN VIVO, BRAIN ISCHEMIA BY CORTICAL DEVASCULARIZATION (PIAL DISRUPTION) WAS PERFORMED TO VERIFY THE PRESENCE OF EPIGENETIC MARKS IN REACTIVE ASTROCYTES. OUR RESULTS SHOWED THAT 1) MICROGLIA IS REQUIRED TO INITIATE THE PATHOLOGICAL CONVERSION OF ASTROCYTES BY TRIGGERING THE NF-KAPPAB SIGNALING PATHWAY; 2) THIS INTERACTION IS MEDIATED BY SOLUBLE FACTORS AND INDUCES STABLE ASTROGLIAL PHENOTYPIC CHANGES; 3) THE PATHOLOGICAL CONVERSION PROMOTES CHROMATIN REMODELING WITH STABLE INCREASE IN H3K9K14AC, TEMPORARY INCREASE IN H3K27AC, AND TEMPORARY REDUCTION IN HETEROCHROMATIN MARK H3K9ME3; AND 4) IN VIVO REACTIVE ASTROCYTES SHOW INCREASED H3K27AC MARK IN THE NEUROINFLAMMATORY MILIEU FROM THE ISCHEMIC PENUMBRA. OUR FINDINGS INDICATE THAT ASTROGLIAL PATHOLOGICAL PRO-INFLAMMATORY GAIN OF FUNCTION IS ASSOCIATED WITH PROFOUND CHANGES IN THE CONFIGURATION OF ASTROCYTIC CHROMATIN, WHICH IN TURN ARE INITIATED BY MICROGLIA-DERIVED CUES. THESE RESULTS OPEN A NEW AVENUE IN THE STUDY OF POTENTIAL PHARMACOLOGICAL INTERVENTIONS THAT MODIFY THE INITIATION AND STABILIZATION OF ASTROGLIAL PATHOLOGICAL REMODELING, WHICH WOULD BE USEFUL IN ACUTE AND CHRONIC CNS INJURY. EPIGENETIC CHANGES REPRESENT A PLAUSIBLE PHARMACOLOGICAL TARGET TO INTERFERE WITH THE STABILIZATION OF THE PATHOLOGICAL ASTROGLIAL PHENOTYPE. 2021 10 5591 25 ROLE OF THE EPIGENETIC FACTOR SIRT7 IN NEUROINFLAMMATION AND NEUROGENESIS. EPIGENETIC REGULATORS ARE INCREASINGLY RECOGNIZED AS RELEVANT MODULATORS IN THE IMMUNE AND NERVOUS SYSTEM. THE CLASS OF SIRTUINS CONSISTS OF NAD(+)-DEPENDENT HISTONE DEACETYLASES THAT REGULATE TRANSCRIPTION. SIRTUIN FAMILY MEMBER SIRT1 HAS ALREADY BEEN SHOWN TO INFLUENCE THE DISEASE COURSE IN AN ANIMAL MODEL OF AUTOIMMUNE NEUROINFLAMMATION (EXPERIMENTAL AUTOIMMUNE ENCEPHALOMYELITIS (EAE). A ROLE OF SIRT7, A RELATED EPIGENETIC REGULATOR, ON IMMUNE SYSTEM REGULATION HAS BEEN PROPOSED BEFORE, AS THESE MICE ARE MORE SUSCEPTIBLE TO DEVELOP INFLAMMATORY CARDIOMYOPATHY. SIRT7(-/-) ANIMALS SHOWED NO DIFFERENCES IN CLINICAL SCORE COMPARED TO WILD-TYPE LITTERMATES AFTER EAE INDUCTION WITH MYELIN OLIGODENDROCYTE GLYCOPROTEIN (MOG) PEPTIDE (35-55), ALTHOUGH WE FOUND SUBTLE IMMUNE ALTERATIONS AT DIFFERENT PHASES OF EAE AND DECREASED SURVIVAL OF NEWLY GENERATED NEURONS IN THE HIPPOCAMPUS. OUR DATA INDICATE THAT SIRT7 HAS A SLIGHT PROTECTIVE IMPACT ON BOTH THE ADAPTIVE IMMUNE SYSTEM AND NEUROGENESIS. HOWEVER, OVERALL THIS EPIGENETIC FACTOR IS NOT CAPABLE OF IMPACTING THE ACUTE OR CHRONIC PHASE OF NEUROINFLAMMATION. 2018 11 4614 28 NERVE EXCITABILITY AND NEUROPATHIC PAIN IS REDUCED BY BET PROTEIN INHIBITION AFTER SPARED NERVE INJURY. NEUROPATHIC PAIN IS A COMMON DISABILITY PRODUCED BY ENHANCED NEURONAL EXCITABILITY AFTER NERVOUS SYSTEM INJURY. THE PATHOPHYSIOLOGICAL CHANGES THAT UNDERLIE THE GENERATION AND MAINTENANCE OF NEUROPATHIC PAIN REQUIRE MODIFICATIONS OF TRANSCRIPTIONAL PROGRAMS. IN PARTICULAR, THERE IS AN INDUCTION OF PRO-INFLAMMATORY NEUROMODULATORS LEVELS, AND CHANGES IN THE EXPRESSION OF ION CHANNELS AND OTHER FACTORS INTERVENING IN THE DETERMINATION OF THE MEMBRANE POTENTIAL IN NEURONAL CELLS. WE HAVE PREVIOUSLY FOUND THAT INHIBITION OF THE BET PROTEINS EPIGENETIC READERS REDUCED NEUROINFLAMMATION AFTER SPINAL CORD INJURY. WITHIN THE PRESENT STUDY WE AIMED TO DETERMINE IF BET PROTEIN INHIBITION MAY ALSO AFFECT NEUROINFLAMMATION AFTER A PERIPHERAL NERVE INJURY, AND IF THIS WOULD BENEFICIALLY ALTER NEURONAL EXCITABILITY AND NEUROPATHIC PAIN. FOR THIS PURPOSE, C57BL/6 FEMALE MICE UNDERWENT SPARED NERVE INJURY (SNI), AND WERE TREATED WITH THE BET INHIBITOR JQ1, OR VEHICLE. ELECTROPHYSIOLOGICAL AND ALGESIMETRY TESTS WERE PERFORMED ON THESE MICE. WE ALSO DETERMINED THE EFFECTS OF JQ1 TREATMENT AFTER INJURY ON NEUROINFLAMMATION, AND THE EXPRESSION OF NEURONAL COMPONENTS IMPORTANT FOR THE MAINTENANCE OF AXON MEMBRANE POTENTIAL. WE FOUND THAT TREATMENT WITH JQ1 AFFECTED NEURONAL EXCITABILITY AND MECHANICAL HYPERALGESIA AFTER SNI IN MICE. BET PROTEIN INHIBITION REGULATED CYTOKINE EXPRESSION AND REDUCED MICROGLIAL REACTIVITY AFTER INJURY. IN ADDITION, JQ1 TREATMENT ALTERED THE EXPRESSION OF SCN3A, SCN9A, KCNA1, KCNQ2, KCNQ3, HCN1 AND HCN2 ION CHANNELS, AS WELL AS THE EXPRESSION OF THE NA(+)/K(+) ATPASE PUMP SUBUNITS. IN CONCLUSION, BOTH, ALTERATION OF INFLAMMATION, AND NEURONAL TRANSCRIPTION, COULD BE THE RESPONSIBLE EPIGENETIC MECHANISMS FOR THE REDUCTION OF EXCITABILITY AND HYPERALGESIA OBSERVED AFTER BET INHIBITION. INHIBITION OF BET PROTEINS IS A PROMISING THERAPY FOR REDUCING NEUROPATHIC PAIN AFTER NEURAL INJURY. PERSPECTIVE: NEUROPATHIC PAIN IS A COMMON DISABILITY PRODUCED BY ENHANCED NEURONAL EXCITABILITY AFTER NERVOUS SYSTEM INJURY. THE UNDERLYING PATHOPHYSIOLOGICAL CHANGES REQUIRE MODIFICATIONS OF TRANSCRIPTIONAL PROGRAMS. THIS STUDY NOTES THAT INHIBITION OF BET PROTEINS IS A PROMISING THERAPY FOR REDUCING NEUROPATHIC PAIN AFTER NEURAL INJURY. 2021 12 533 35 ASTROCYTIC TRANSCRIPTION FACTOR REST UPREGULATES GLUTAMATE TRANSPORTER EAAT2, PROTECTING DOPAMINERGIC NEURONS FROM MANGANESE-INDUCED EXCITOTOXICITY. CHRONIC EXPOSURE TO HIGH LEVELS OF MANGANESE (MN) LEADS TO MANGANISM, A NEUROLOGICAL DISORDER WITH SIMILAR SYMPTOMS TO THOSE INHERENT TO PARKINSON'S DISEASE. HOWEVER, THE UNDERLYING MECHANISMS OF THIS PATHOLOGICAL CONDITION HAVE YET TO BE ESTABLISHED. SINCE THE HUMAN EXCITATORY AMINO ACID TRANSPORTER 2 (EAAT2) (GLUTAMATE TRANSPORTER 1 IN RODENTS) IS PREDOMINANTLY EXPRESSED IN ASTROCYTES AND ITS DYSREGULATION IS INVOLVED IN MN-INDUCED EXCITOTOXIC NEURONAL INJURY, CHARACTERIZATION OF THE MECHANISMS THAT MEDIATE THE MN-INDUCED IMPAIRMENT IN EAAT2 FUNCTION IS CRUCIAL FOR THE DEVELOPMENT OF NOVEL THERAPEUTICS AGAINST MN NEUROTOXICITY. REPRESSOR ELEMENT 1-SILENCING TRANSCRIPTION FACTOR (REST) EXERTS PROTECTIVE EFFECTS IN MANY NEURODEGENERATIVE DISEASES. BUT THE EFFECTS OF REST ON EAAT2 EXPRESSION AND ENSUING NEUROPROTECTION ARE UNKNOWN. GIVEN THAT THE EAAT2 PROMOTER CONTAINS REST BINDING SITES, THE PRESENT STUDY INVESTIGATED THE ROLE OF REST IN EAAT2 EXPRESSION AT THE TRANSCRIPTIONAL LEVEL IN ASTROCYTES AND MN-INDUCED NEUROTOXICITY IN AN ASTROCYTE-NEURON COCULTURE SYSTEM. THE RESULTS REVEAL THAT ASTROCYTIC REST POSITIVELY REGULATES EAAT2 EXPRESSION WITH THE RECRUITMENT OF AN EPIGENETIC MODIFIER, CAMP RESPONSE ELEMENT-BINDING PROTEIN-BINDING PROTEIN/P300, TO ITS CONSENSUS BINDING SITES IN THE EAAT2 PROMOTER. MOREOVER, ASTROCYTIC OVEREXPRESSION OF REST ATTENUATES MN-INDUCED REDUCTION IN EAAT2 EXPRESSION, LEADING TO ATTENUATION OF GLUTAMATE-INDUCED NEUROTOXICITY IN THE ASTROCYTE-NEURON COCULTURE SYSTEM. OUR FINDINGS DEMONSTRATE THAT ASTROCYTIC REST PLAYS A CRITICAL ROLE IN PROTECTION AGAINST MN-INDUCED NEUROTOXICITY BY ATTENUATING MN-INDUCED EAAT2 REPRESSION AND THE ENSUING EXCITOTOXIC DOPAMINERGIC NEURONAL INJURY. THIS INDICATES THAT ASTROCYTIC REST COULD BE A POTENTIAL MOLECULAR TARGET FOR THE TREATMENT OF MN TOXICITY AND OTHER NEUROLOGICAL DISORDERS ASSOCIATED WITH EAAT2 DYSREGULATION. 2021 13 2272 23 EPIGENETIC REDUCTION OF MIR-214-3P UPREGULATES ASTROCYTIC COLONY-STIMULATING FACTOR-1 AND CONTRIBUTES TO NEUROPATHIC PAIN INDUCED BY NERVE INJURY. EMERGING EVIDENCE HAS INDICATED THAT COLONY-STIMULATING FACTOR-1 (CSF1) MODULATES NEUROINFLAMMATION IN THE CENTRAL NERVOUS SYSTEM AND THE DEVELOPMENT OF NEUROPATHIC PAIN, WHILE THE UNDERLYING MECHANISM REMAINS UNKNOWN. HERE, WE IDENTIFIED THE INCREASED EXPRESSION OF CSF1 DERIVED FROM ACTIVATED ASTROCYTES IN THE IPSILATERAL DORSAL HORN IN RATS WITH SPINAL NERVE LIGATION (SNL). SUPPRESSION OF CSF1 EXPRESSION ALLEVIATED NEUROINFLAMMATION, NEURONAL HYPEREXCITABILITY, AND GLUTAMATERGIC RECEPTOR SUBUNIT UPREGULATION IN THE DORSAL HORN AND IMPROVED SNL-INDUCED PAIN BEHAVIOR. WE ALSO FOUND REDUCED MIR-214-3P EXPRESSION IN THE IPSILATERAL DORSAL HORN FOLLOWING AN SNL PROCEDURE; MIR-214-3P DIRECTLY BOUND TO THE 3'-UTR OF CSF1 MRNA AND NEGATIVELY REGULATED CSF1 EXPRESSION. INTRATHECAL DELIVERY OF MIR-214-3P MIMIC REVERSED THE ENHANCED EXPRESSION OF CSF1 AND ASTROCYTE OVERACTIVITY AND ALLEVIATED THE IL-6 UPREGULATION AND PAIN BEHAVIOR INDUCED BY SNL. MOREOVER, SUPPRESSION OF SPINAL MIR-214-3P INCREASED ASTROCYTE REACTIVITY, PROMOTED CSF1 AND IL-6 PRODUCTION, AND INDUCED PAIN HYPERSENSITIVITY IN NAIVE ANIMALS. FURTHERMORE, SNL INDUCED THE EXPRESSION OF DNA METHYLTRANSFERASE 3A (DNMT3A) THAT WAS ASSOCIATED WITH THE HYPERMETHYLATION OF THE MIR-214-3P PROMOTER, LEADING TO REDUCED MIR-214-3P EXPRESSION IN THE MODEL RODENTS. TREATMENT WITH THE DNMT INHIBITOR ZEBULARINE SIGNIFICANTLY REDUCED CYTOSINE METHYLATION IN THE MIR-214-3P PROMOTER; THIS REDUCED METHYLATION CONSEQUENTLY INCREASED THE EXPRESSION OF MIR-214-3P AND DECREASED THE CONTENT OF CSF1 IN THE IPSILATERAL DORSAL HORN AND, FURTHER, ATTENUATED IL-6 PRODUCTION AND PAIN BEHAVIOR IN RATS WITH SNL. TOGETHER, OUR DATA INDICATE THAT THE DNMT3A-MEDIATED EPIGENETIC SUPPRESSION OF MIR-214-3P ENHANCED CSF1 PRODUCTION IN ASTROCYTES, WHICH SUBSEQUENTLY INDUCED NEUROINFLAMMATION AND PAIN BEHAVIOR IN SNL MODEL RATS. 2020 14 4620 26 NEURO-IMMUNE DYSFUNCTION DURING BRAIN AGING: NEW INSIGHTS IN MICROGLIAL CELL REGULATION. MICROGLIA, THE RESIDENT IMMUNE CELLS OF THE BRAIN, ARE AT THE CENTER OF COMMUNICATION BETWEEN THE CENTRAL NERVOUS SYSTEM AND IMMUNE SYSTEM. WHILE THESE BRAIN-IMMUNE INTERACTIONS ARE BALANCED IN HEALTHY ADULTHOOD, THE ABILITY TO MAINTAIN HOMEOSTASIS DURING AGING IS IMPAIRED. MICROGLIA DEVELOP A LOSS OF INTEGRATED REGULATORY NETWORKS INCLUDING ABERRANT SIGNALING FROM OTHER BRAIN CELLS, IMMUNE SENSORS, AND EPIGENETIC MODIFIERS. THE LOW-GRADE CHRONIC NEUROINFLAMMATION ASSOCIATED WITH THIS DYSFUNCTIONAL ACTIVITY LIKELY CONTRIBUTES TO COGNITIVE DEFICITS AND SUSCEPTIBILITY TO AGE-RELATED PATHOLOGIES. A BETTER UNDERSTANDING OF THE UNDERLYING MECHANISMS RESPONSIBLE FOR NEURO-IMMUNE DYSREGULATION WITH AGE IS CRUCIAL FOR PROVIDING TARGETED THERAPEUTIC STRATEGIES TO SUPPORT BRAIN REPAIR AND HEALTHY AGING. 2016 15 3675 23 INFLAMMATION AND HISTONE MODIFICATION IN CHRONIC PAIN. INCREASING EVIDENCE SUGGESTS THAT EPIGENETIC MECHANISMS HAVE GREAT POTENTIAL IN THE FIELD OF PAIN. THE CHANGES AND ROLES OF EPIGENETICS OF THE SPINAL CORD AND DORSAL ROOT GANGLIA IN THE CHRONIC PAIN PROCESS MAY PROVIDE BROAD INSIGHTS FOR FUTURE PAIN MANAGEMENT. PRO-INFLAMMATORY CYTOKINES AND CHEMOKINES RELEASED BY MICROGLIA AND ASTROCYTES, AS WELL AS BLOOD-DERIVED MACROPHAGES, PLAY CRITICAL ROLES IN INDUCING AND MAINTAINING CHRONIC PAIN, WHILE HISTONE MODIFICATIONS MAY PLAY AN IMPORTANT ROLE IN INFLAMMATORY METABOLISM. THIS REVIEW PROVIDES AN OVERVIEW OF NEUROINFLAMMATION AND CHRONIC PAIN, AND WE SYSTEMATICALLY DISCUSS THE REGULATION OF NEUROINFLAMMATION AND HISTONE MODIFICATIONS IN THE CONTEXT OF CHRONIC PAIN. SPECIFICALLY, WE ANALYZED THE ROLE OF EPIGENETICS IN ALLEVIATING OR EXACERBATING CHRONIC PAIN BY MODULATING MICROGLIA, ASTROCYTES, AND THE PROINFLAMMATORY MEDIATORS THEY RELEASE. THIS REVIEW AIMED TO CONTRIBUTE TO THE DISCOVERY OF NEW THERAPEUTIC TARGETS FOR CHRONIC PAIN. 2022 16 4138 37 MECHANISMS OF MICROGLIAL ACTIVATION IN MODELS OF INFLAMMATION AND HYPOXIA: IMPLICATIONS FOR CHRONIC INTERMITTENT HYPOXIA. CHRONIC INTERMITTENT HYPOXIA (CIH) IS A HALLMARK OF SLEEP APNOEA, A CONDITION ASSOCIATED WITH DIVERSE CLINICAL DISORDERS. CIH AND SLEEP APNOEA ARE CHARACTERIZED BY INCREASED REACTIVE OXYGEN SPECIES FORMATION, PERIPHERAL AND CNS INFLAMMATION, NEURONAL DEATH AND NEUROCOGNITIVE DEFICITS. FEW STUDIES HAVE EXAMINED THE ROLE OF MICROGLIA, THE RESIDENT CNS IMMUNE CELLS, IN MODELS OF CIH. THUS, LITTLE IS KNOWN CONCERNING THEIR DIRECT CONTRIBUTIONS TO NEUROPATHOLOGY OR THE CELLULAR MECHANISMS REGULATING THEIR ACTIVITIES DURING OR FOLLOWING PATHOLOGICAL CIH. IN THIS REVIEW, WE IDENTIFY GAPS IN KNOWLEDGE REGARDING CIH-INDUCED MICROGLIAL ACTIVATION, AND PROPOSE MECHANISMS BASED ON DATA FROM RELATED MODELS OF HYPOXIA AND/OR HYPOXIA-REOXYGENATION. CIH MAY DIRECTLY AFFECT MICROGLIA, OR MAY HAVE INDIRECT EFFECTS VIA THE PERIPHERY OR OTHER CNS CELLS. PERIPHERAL INFLAMMATION MAY INDIRECTLY ACTIVATE MICROGLIA VIA ENTRY OF PRO-INFLAMMATORY MOLECULES INTO THE CNS, AND/OR ACTIVATION OF VAGAL AFFERENTS THAT TRIGGER CNS INFLAMMATION. CIH-INDUCED RELEASE OF DAMAGE-ASSOCIATED MOLECULAR PATTERNS FROM INJURED CNS CELLS MAY ALSO ACTIVATE MICROGLIA VIA INTERACTIONS WITH PATTERN RECOGNITION RECEPTORS EXPRESSED ON MICROGLIA. FOR EXAMPLE, TOLL-LIKE RECEPTORS ACTIVATE MITOGEN-ACTIVATED PROTEIN KINASE/TRANSCRIPTION FACTOR PATHWAYS REQUIRED FOR MICROGLIAL INFLAMMATORY GENE EXPRESSION. ALTHOUGH EPIGENETIC EFFECTS FROM CIH HAVE NOT YET BEEN STUDIED IN MICROGLIA, POTENTIAL EPIGENETIC MECHANISMS IN MICROGLIAL REGULATION ARE DISCUSSED, INCLUDING MICRORNAS, HISTONE MODIFICATIONS AND DNA METHYLATION. EPIGENETIC EFFECTS CAN OCCUR DURING CIH, OR LONG AFTER IT HAS ENDED. A BETTER UNDERSTANDING OF CIH EFFECTS ON MICROGLIAL ACTIVITIES MAY BE IMPORTANT TO REVERSE CIH-INDUCED NEUROPATHOLOGY IN PATIENTS WITH SLEEP DISORDERED BREATHING. 2016 17 3736 39 INNATE IMMUNE TOLERANCE IN MICROGLIA DOES NOT IMPACT ON CENTRAL NERVOUS SYSTEM PRION DISEASE. PRION DISEASES SUCH AS CREUTZFELDT-JAKOB DISEASE IN HUMANS, BOVINE SPONGIFORM ENCEPHALOPATHY IN CATTLE, AND SCRAPIE IN SHEEP, ARE INFECTIOUS AND CHRONIC NEURODEGENERATIVE DISEASES TO WHICH THERE ARE NO CURES. INFECTION WITH PRIONS IN THE CENTRAL NERVOUS SYSTEM (CNS) ULTIMATELY CAUSES EXTENSIVE NEURODEGENERATION, AND THIS IS ACCOMPANIED BY PROMINENT MICROGLIAL AND ASTROCYTIC ACTIVATION IN AFFECTED REGIONS. THE MICROGLIA ARE THE CNS MACROPHAGES AND HELP MAINTAIN NEURONAL HOMEOSTASIS, CLEAR DEAD OR DYING CELLS AND PROVIDE DEFENSE AGAINST PATHOGENS. THE MICROGLIA ALSO PROVIDE NEUROPROTECTION DURING CNS PRION DISEASE, BUT THEIR PRO-INFLAMMATORY ACTIVATION MAY EXACERBATE THE DEVELOPMENT OF THE NEUROPATHOLOGY. INNATE IMMUNE TOLERANCE INDUCED BY CONSECUTIVE SYSTEMIC BACTERIAL LIPOPOLYSACCHARIDE (LPS) TREATMENT CAN INDUCE LONG-TERM EPIGENETIC CHANGES IN THE MICROGLIA IN THE BRAIN THAT SEVERAL MONTHS LATER CAN DAMPEN THEIR RESPONSIVENESS TO SUBSEQUENT LPS TREATMENT AND IMPEDE THE DEVELOPMENT OF NEURITIC DAMAGE IN A TRANSGENIC MOUSE MODEL OF ALZHEIMER'S DISEASE-LIKE PATHOLOGY. WE THEREFORE REASONED THAT INNATE IMMUNE TOLERANCE IN MICROGLIA MIGHT SIMILARLY IMPEDE THE SUBSEQUENT DEVELOPMENT OF CNS PRION DISEASE. TO TEST THIS HYPOTHESIS GROUPS OF MICE WERE FIRST INFECTED WITH PRIONS BY INTRACEREBRAL INJECTION, AND 35 DAYS LATER GIVEN FOUR CONSECUTIVE SYSTEMIC INJECTIONS WITH LPS TO INDUCE INNATE IMMUNE TOLERANCE. OUR DATA SHOW THAT CONSECUTIVE SYSTEMIC LPS TREATMENT DID NOT AFFECT THE SUBSEQUENT DEVELOPMENT OF CNS PRION DISEASE. OUR DATA SUGGESTS INNATE IMMUNE TOLERANCE IN MICROGLIA DOES NOT INFLUENCE THE SUBSEQUENT ONSET OF PRION DISEASE-INDUCED NEUROPATHOLOGY IN MICE, DESPITE PREVIOUSLY PUBLISHED EVIDENCE OF THIS EFFECT IN AN ALZHEIMER'S DISEASE MOUSE MODEL. 2022 18 1105 32 COMBINED INHIBITION OF HISTONE DEACETYLASES AND BET FAMILY PROTEINS AS EPIGENETIC THERAPY FOR NERVE INJURY-INDUCED NEUROPATHIC PAIN. CURRENT TREATMENTS FOR NEUROPATHIC PAIN HAVE OFTEN MODERATE EFFICACY AND PRESENT UNWANTED EFFECTS SHOWING THE NEED TO DEVELOP EFFECTIVE THERAPIES. ACCUMULATING EVIDENCE SUGGESTS THAT HISTONE ACETYLATION PLAYS ESSENTIAL ROLES IN CHRONIC PAIN AND THE ANALGESIC ACTIVITY OF HISTONE DEACETYLASES (HDACS) INHIBITORS IS DOCUMENTED. BROMODOMAIN AND EXTRA-TERMINAL DOMAIN (BET) PROTEINS ARE EPIGENETIC READERS THAT INTERACT WITH ACETYLATED LYSINE RESIDUES ON HISTONES, BUT LITTLE IS KNOWN ABOUT THEIR IMPLICATION IN NEUROPATHIC PAIN. THUS, THE CURRENT STUDY WAS AIMED TO INVESTIGATE THE EFFECT OF THE COMBINATION OF HDAC AND BET INHIBITORS IN THE SPARED NERVE INJURY (SNI) MODEL IN MICE. INTRANASAL ADMINISTRATION OF I-BET762 (BET INHIBITOR) OR SAHA (HDAC INHIBITOR) ATTENUATED THERMAL AND MECHANICAL HYPERSENSITIVITY AND THIS ANTIALLODYNIC ACTIVITY WAS IMPROVED BY CO-ADMINISTRATION OF BOTH DRUGS. SPINAL CORD SECTIONS OF SNI MICE SHOWED AN INCREASED EXPRESSION OF HDAC1 AND BRD4 PROTEINS AND COMBINATION PRODUCED A STRONGER REDUCTION COMPARED TO EACH EPIGENETIC AGENT ALONE. SAHA AND I-BET762, ADMINISTERED ALONE OR IN COMBINATION, COUNTERACTED THE SNI-INDUCED MICROGLIA ACTIVATION BY INHIBITING THE EXPRESSION OF IBA1, CD11B, INDUCIBLE NITRIC OXIDE SYNTHASE (INOS), THE ACTIVATION OF NUCLEAR FACTOR-KAPPAB (NF-KAPPAB) AND SIGNAL TRANSDUCER AND ACTIVATOR OF TRANSCRIPTION-1 (STAT1) WITH COMPARABLE EFFICACY. CONVERSELY, THE EPIGENETIC INHIBITORS SHOWED A MODEST EFFECT ON SPINAL PROINFLAMMATORY CYTOKINES CONTENT THAT WAS SIGNIFICANTLY POTENTIATED BY THEIR COMBINATION. PRESENT RESULTS INDICATE A KEY ROLE OF ACETYLATED HISTONES AND THEIR RECRUITMENT BY BET PROTEINS ON MICROGLIA-MEDIATED SPINAL NEUROINFLAMMATION. TARGETING NEUROPATHIC PAIN WITH THE COMBINATION OF HDAC AND BET INHIBITORS MAY REPRESENT A PROMISING NEW THERAPEUTIC OPTION. 2021 19 4304 30 MICRORNA-223 PROTECTS NEURONS FROM DEGENERATION IN EXPERIMENTAL AUTOIMMUNE ENCEPHALOMYELITIS. MULTIPLE SCLEROSIS IS A CHRONIC INFLAMMATORY, DEMYELINATING, AND NEURODEGENERATIVE DISEASE AFFECTING THE BRAIN, SPINAL CORD AND OPTIC NERVES. NEURONAL DAMAGE IS TRIGGERED BY VARIOUS HARMFUL FACTORS THAT ENGAGE DIVERSE SIGNALLING CASCADES IN NEURONS; THUS, THERAPEUTIC APPROACHES TO PROTECT NEURONS WILL NEED TO FOCUS ON AGENTS THAT CAN TARGET MULTIPLE BIOLOGICAL PROCESSES. WE HAVE THEREFORE FOCUSED OUR ATTENTION ON MICRORNAS: SMALL NON-CODING RNAS THAT PRIMARILY FUNCTION AS POST-TRANSCRIPTIONAL REGULATORS THAT TARGET MESSENGER RNAS AND REPRESS THEIR TRANSLATION INTO PROTEINS. A SINGLE MICRORNA CAN TARGET MANY FUNCTIONALLY RELATED MESSENGER RNAS MAKING MICRORNAS POWERFUL EPIGENETIC REGULATORS. DYSREGULATION OF MICRORNAS HAS BEEN DESCRIBED IN MANY NEURODEGENERATIVE DISEASES INCLUDING MULTIPLE SCLEROSIS. HERE, WE REPORT THAT TWO MICRORNAS, MIR-223-3P AND MIR-27A-3P, ARE UPREGULATED IN NEURONS IN THE EXPERIMENTAL AUTOIMMUNE ENCEPHALOMYELITIS MOUSE MODEL OF CNS INFLAMMATION AND IN GREY MATTER-CONTAINING MULTIPLE SCLEROSIS LESIONS. PRIOR WORK HAS SHOWN PERIPHERAL BLOOD MONONUCLEAR CELL CONDITIONED MEDIA CAUSES SUBLETHAL DEGENERATION OF NEURONS IN CULTURE. WE FIND OVEREXPRESSION OF MIR-27A-3P OR MIR-223-3P PROTECTS DISSOCIATED CORTICAL NEURONS FROM CONDITION MEDIA MEDIATED DEGENERATION. INTRODUCTION OF MIR-223-3P IN VIVO IN MOUSE RETINAL GANGLION CELLS PROTECTS THEIR AXONS FROM DEGENERATION IN EXPERIMENTAL AUTOIMMUNE ENCEPHALOMYELITIS. IN SILICO ANALYSIS REVEALED THAT MESSENGER RNAS INVOLVED IN GLUTAMATE RECEPTOR SIGNALLING ARE ENRICHED AS MIR-27A-3P AND MIR-223-3P TARGETS. WE OBSERVE THAT ANTAGONISM OF NMDA AND AMPA TYPE GLUTAMATE RECEPTORS PROTECTS NEURONS FROM CONDITION MEDIA DEPENDENT DEGENERATION. OUR RESULTS SUGGEST THAT MIR-223-3P AND MIR-27A-3P ARE UPREGULATED IN RESPONSE TO INFLAMMATION TO MEDIATE A COMPENSATORY NEUROPROTECTIVE GENE EXPRESSION PROGRAM THAT DESENSITIZES NEURONS TO GLUTAMATE BY TARGETING MESSENGER RNAS INVOLVED IN GLUTAMATE RECEPTOR SIGNALLING. 2019 20 3587 35 IMPACT OF TLR4 ON BEHAVIORAL AND COGNITIVE DYSFUNCTIONS ASSOCIATED WITH ALCOHOL-INDUCED NEUROINFLAMMATORY DAMAGE. TOLL-LIKE RECEPTORS (TLRS) PLAY AN IMPORTANT ROLE IN THE INNATE IMMUNE RESPONSE, AND EMERGING EVIDENCE INDICATES THEIR ROLE IN BRAIN INJURY AND NEURODEGENERATION. OUR RECENT RESULTS HAVE DEMONSTRATED THAT ETHANOL IS CAPABLE OF ACTIVATING GLIAL TLR4 RECEPTORS AND THAT THE ELIMINATION OF THESE RECEPTORS IN MICE PROTECTS AGAINST ETHANOL-INDUCED GLIAL ACTIVATION, INDUCTION OF INFLAMMATORY MEDIATORS AND APOPTOSIS. THIS STUDY WAS DESIGNED TO ASSESS WHETHER ETHANOL-INDUCED INFLAMMATORY DAMAGE CAUSES BEHAVIORAL AND COGNITIVE CONSEQUENCES, AND IF BEHAVIORAL ALTERATIONS ARE DEPENDENT OF TLR4 FUNCTIONS. HERE WE SHOW IN MICE DRINKING ALCOHOL FOR 5MONTHS, FOLLOWED BY A 15-DAY WITHDRAWAL PERIOD, THAT ACTIVATION OF THE ASTROGLIAL AND MICROGLIAL CELLS IN FRONTAL CORTEX AND STRIATUM IS MAINTAINED AND THAT THESE EVENTS ARE ASSOCIATED WITH COGNITIVE AND ANXIETY-RELATED BEHAVIORAL IMPAIRMENTS IN WILD-TYPE (WT) MICE, AS DEMONSTRATED BY TESTING THE ANIMALS WITH OBJECT MEMORY RECOGNITION, CONDITIONED TASTE AVERSION AND DARK AND LIGHT BOX ANXIETY TASKS. MICE LACKING TLR4 RECEPTORS ARE PROTECTED AGAINST ETHANOL-INDUCED INFLAMMATORY DAMAGE, AND BEHAVIORAL ASSOCIATED EFFECTS. WE FURTHER ASSESS THE POSSIBILITY OF THE EPIGENETIC MODIFICATIONS PARTICIPATING IN SHORT- OR LONG-TERM BEHAVIORAL EFFECTS ASSOCIATED WITH NEUROINFLAMMATORY DAMAGE. WE SHOW THAT CHRONIC ALCOHOL TREATMENT DECREASES H4 HISTONE ACETYLATION AND HISTONE ACETYLTRANSFERASES ACTIVITY IN FRONTAL CORTEX, STRIATUM AND HIPPOCAMPUS OF WT MICE. ALTERATIONS IN CHROMATIN STRUCTURE WERE NOT OBSERVED IN TLR4(-/-) MICE. THESE RESULTS PROVIDE THE FIRST EVIDENCE OF THE ROLE THAT TLR4 FUNCTIONS PLAY IN THE BEHAVIORAL CONSEQUENCES OF ALCOHOL-INDUCED INFLAMMATORY DAMAGE AND SUGGEST THAT THE EPIGENETIC MODIFICATIONS MEDIATED BY TLR4 COULD CONTRIBUTE TO SHORT- OR LONG-TERM ALCOHOL-INDUCED BEHAVIORAL OR COGNITIVE DYSFUNCTIONS. 2011