1 6024 129 THE BIOCHEMISTRY AND EPIGENETICS OF EPILEPSY: FOCUS ON ADENOSINE AND GLYCINE. EPILEPSY, ONE OF THE MOST PREVALENT NEUROLOGICAL CONDITIONS, PRESENTS AS A COMPLEX DISORDER OF NETWORK HOMEOSTASIS CHARACTERIZED BY SPONTANEOUS NON-PROVOKED SEIZURES AND ASSOCIATED COMORBIDITIES. CURRENTLY USED ANTIEPILEPTIC DRUGS HAVE BEEN DESIGNED TO SUPPRESS NEURONAL HYPEREXCITABILITY AND THEREBY TO SUPPRESS EPILEPTIC SEIZURES. HOWEVER, THE CURRENT ARMAMENTARIUM OF ANTIEPILEPTIC DRUGS IS NOT EFFECTIVE IN OVER 30% OF PATIENTS, DOES NOT AFFECT THE COMORBIDITIES OF EPILEPSY, AND DOES NOT PREVENT THE DEVELOPMENT AND PROGRESSION OF EPILEPSY (EPILEPTOGENESIS). PREVENTION OF EPILEPSY AND ITS PROGRESSION REMAINS THE HOLY GRAIL FOR EPILEPSY RESEARCH AND THERAPY DEVELOPMENT, REQUIRING NOVEL CONCEPTUAL ADVANCES TO FIND A SOLUTION TO THIS URGENT MEDICAL NEED. THE METHYLATION HYPOTHESIS OF EPILEPTOGENESIS SUGGESTS THAT CHANGES IN DNA METHYLATION ARE IMPLICATED IN THE PROGRESSION OF THE DISEASE. IN PARTICULAR, GLOBAL DNA HYPERMETHYLATION APPEARS TO BE ASSOCIATED WITH CHRONIC EPILEPSY. CLINICAL AS WELL AS EXPERIMENTAL EVIDENCE DEMONSTRATES THAT EPILEPSY AND ITS PROGRESSION CAN BE PREVENTED BY BIOCHEMICAL MANIPULATIONS AND THOSE THAT TARGET PREVIOUSLY UNRECOGNIZED EPIGENETIC FUNCTIONS CONTRIBUTING TO EPILEPSY DEVELOPMENT AND MAINTENANCE OF THE EPILEPTIC STATE. THIS MINI-REVIEW WILL DISCUSS, EPIGENETIC MECHANISMS IMPLICATED IN EPILEPTOGENESIS AND BIOCHEMICAL INTERACTIONS BETWEEN ADENOSINE AND GLYCINE AS A CONCEPTUAL ADVANCE TO UNDERSTAND THE CONTRIBUTION OF MALADAPTIVE CHANGES IN BIOCHEMISTRY AS A MAJOR CONTRIBUTING FACTOR TO THE DEVELOPMENT OF EPILEPSY. NEW FINDINGS BASED ON BIOCHEMICAL MANIPULATION OF THE DNA METHYLOME SUGGEST THAT: (I) EPIGENETIC MECHANISMS PLAY A FUNCTIONAL ROLE IN EPILEPTOGENESIS; AND (II) THERAPEUTIC RECONSTRUCTION OF THE EPIGENOME IS AN EFFECTIVE ANTIEPILEPTOGENIC THERAPY. 2016 2 1652 29 DOPAMINE SIGNALING LEADS TO LOSS OF POLYCOMB REPRESSION AND ABERRANT GENE ACTIVATION IN EXPERIMENTAL PARKINSONISM. POLYCOMB GROUP (PCG) PROTEINS BIND TO AND REPRESS GENES IN EMBRYONIC STEM CELLS THROUGH LINEAGE COMMITMENT TO THE TERMINAL DIFFERENTIATED STATE. PCG REPRESSED GENES ARE COMMONLY CHARACTERIZED BY THE PRESENCE OF THE EPIGENETIC HISTONE MARK H3K27ME3, CATALYZED BY THE POLYCOMB REPRESSIVE COMPLEX 2. HERE, WE PRESENT IN VIVO EVIDENCE FOR A PREVIOUSLY UNRECOGNIZED PLASTICITY OF PCG-REPRESSED GENES IN TERMINALLY DIFFERENTIATED BRAIN NEURONS OF PARKISONIAN MICE. WE SHOW THAT ACUTE ADMINISTRATION OF THE DOPAMINE PRECURSOR, L-DOPA, INDUCES A REMARKABLE INCREASE IN H3K27ME3S28 PHOSPHORYLATION. THE INDUCTION OF THE H3K27ME3S28P HISTONE MARK SPECIFICALLY OCCURS IN MEDIUM SPINY NEURONS EXPRESSING DOPAMINE D1 RECEPTORS AND IS DEPENDENT ON MSK1 KINASE ACTIVITY AND DARPP-32-MEDIATED INHIBITION OF PROTEIN PHOSPHATASE-1. CHROMATIN IMMUNOPRECIPITATION (CHIP) EXPERIMENTS SHOWED THAT INCREASED H3K27ME3S28P WAS ACCOMPANIED BY REDUCED PCG BINDING TO REGULATORY REGIONS OF GENES. AN ANALYSIS OF THE GENOME WIDE DISTRIBUTION OF L-DOPA-INDUCED H3K27ME3S28 PHOSPHORYLATION BY CHIP SEQUENCING (CHIP-SEQ) IN COMBINATION WITH EXPRESSION ANALYSIS BY RNA-SEQUENCING (RNA-SEQ) SHOWED THAT THE INDUCTION OF H3K27ME3S28P CORRELATED WITH INCREASED EXPRESSION OF A SUBSET OF PCG REPRESSED GENES. WE FOUND THAT INDUCTION OF H3K27ME3S28P PERSISTED DURING CHRONIC L-DOPA ADMINISTRATION TO PARKISONIAN MICE AND CORRELATED WITH ABERRANT GENE EXPRESSION. WE PROPOSE THAT DOPAMINERGIC TRANSMISSION CAN ACTIVATE PCG REPRESSED GENES IN THE ADULT BRAIN AND THEREBY CONTRIBUTE TO LONG-TERM MALADAPTIVE RESPONSES INCLUDING THE MOTOR COMPLICATIONS, OR DYSKINESIA, CAUSED BY PROLONGED ADMINISTRATION OF L-DOPA IN PARKINSON'S DISEASE. 2014 3 2498 76 EPIGENETICS AND EPILEPSY PREVENTION: THE THERAPEUTIC POTENTIAL OF ADENOSINE AND METABOLIC THERAPIES. PREVENTION OF EPILEPSY AND ITS PROGRESSION REMAINS THE MOST URGENT NEED FOR EPILEPSY RESEARCH AND THERAPY DEVELOPMENT. NOVEL CONCEPTUAL ADVANCES ARE REQUIRED TO MEANINGFULLY ADDRESS THIS FUNDAMENTAL CHALLENGE. MALADAPTIVE EPIGENETIC CHANGES, WHICH INCLUDE METHYLATION OF DNA AND ACETYLATION OF HISTONES - AMONG OTHER MECHANISMS, ARE NOW WELL RECOGNIZED TO PLAY A FUNCTIONAL ROLE IN THE DEVELOPMENT OF EPILEPSY AND ITS PROGRESSION. THE METHYLATION HYPOTHESIS OF EPILEPTOGENESIS SUGGESTS THAT CHANGES IN DNA METHYLATION ARE IMPLICATED IN THE PROGRESSION OF THE DISEASE. IN THIS CONTEXT, GLOBAL DNA HYPERMETHYLATION IS PARTICULARLY ASSOCIATED WITH CHRONIC EPILEPSY. LIKEWISE, ACETYLATION CHANGES OF HISTONES HAVE BEEN LINKED TO EPILEPSY DEVELOPMENT. CLINICAL AS WELL AS EXPERIMENTAL EVIDENCE DEMONSTRATE THAT EPILEPSY AND ITS PROGRESSION CAN BE PREVENTED BY METABOLIC AND BIOCHEMICAL MANIPULATIONS THAT TARGET PREVIOUSLY UNRECOGNIZED EPIGENETIC FUNCTIONS CONTRIBUTING TO EPILEPSY DEVELOPMENT AND MAINTENANCE OF THE EPILEPTIC STATE. THIS REVIEW WILL DISCUSS EPIGENETIC MECHANISMS IMPLICATED IN EPILEPSY DEVELOPMENT AS WELL AS METABOLIC AND BIOCHEMICAL INTERACTIONS THOUGHT TO DRIVE EPILEPTOGENESIS. THEREFORE, METABOLIC AND BIOCHEMICAL MECHANISMS ARE IDENTIFIED AS NOVEL TARGETS FOR EPILEPSY PREVENTION. WE WILL SPECIFICALLY DISCUSS ADENOSINE BIOCHEMISTRY AS A NOVEL THERAPEUTIC STRATEGY TO RECONSTRUCT THE DNA METHYLOME AS ANTIEPILEPTOGENIC STRATEGY AS WELL AS METABOLIC MEDIATORS, SUCH AS BETA-HYDROXYBUTYRATE, WHICH AFFECT HISTONE ACETYLATION. FINALLY, METABOLIC DIETARY INTERVENTIONS (SUCH AS THE KETOGENIC DIET) WHICH HAVE THE UNIQUE POTENTIAL TO PREVENT EPILEPTOGENESIS THROUGH RECENTLY IDENTIFIED EPIGENETIC MECHANISMS WILL BE REVIEWED. THIS ARTICLE IS PART OF THE SPECIAL ISSUE ENTITLED 'NEW EPILEPSY THERAPIES FOR THE 21ST CENTURY - FROM ANTISEIZURE DRUGS TO PREVENTION, MODIFICATION AND CURE OF EPILEPSY'. 2020 4 1407 29 DIETARY INFLUENCES ON MUTAGENESIS--WHERE IS THIS FIELD GOING? EARLY STUDIES ON DIETARY MUTAGENESIS WERE MOSTLY OBSERVATIONAL, WITH LARGE NUMBERS OF POTENTIAL DIETARY MUTAGENS BEING IDENTIFIED FROM EVERY CONCEIVABLE DIETARY SOURCE. THESE INCLUDED KNOWN DIETARY CARCINOGENS SUCH AS AFLATOXIN B1 AND BENZO[A]PYRENE, AND HITHERTO UNRECOGNIZED DIETARY MUTAGENS, SUCH AS THE PYROLYSIS PRODUCTS FORMED DURING THE HEATING OF PROTEINACEOUS MATERIALS (HETEROCYCLIC AMINES). THE 1993 EVALUATION OF 2-AMINO-3-METHYL-3H-IMIDAZO(4,5-J)QUINOLINE AS A PROBABLE HUMAN CARCINOGEN BY THE INTERNATIONAL AGENCY FOR RESEARCH ON CANCER WAS A LANDMARK, AS THIS WAS DONE IN THE ABSENCE OF SPECIFIC HUMAN CARCINOGENICITY DATA, AND STRONGLY INFLUENCED BY MUTAGENICITY TEST DATA. IN THE 21ST CENTURY, THE FIELD HAS MOVED FROM THE IDENTIFICATION OF MORE AND MORE MUTAGENS, TO MOLECULAR EPIDEMIOLOGIC APPROACHES THAT NOT ONLY SHOW A MUTAGENIC EFFECT BUT ALSO SEEK TO LINK IT TO A DIETARY (OR ENVIRONMENTAL) CAUSE. EFFECTS OF DIET IN STIMULATING CHRONIC INFLAMMATION MAY LEAD TO REACTIVE SPECIES AND THEREBY MUTATION AS A SECONDARY CONSEQUENCE, WHILE DIETARY DEFICIENCIES AND NUTRIENT IMBALANCES MAY BE STRONG SOURCES OF MUTAGENESIS. RECOGNITION OF THE ROLES OF NUTRIENTS IN CELL SIGNALING PROCESSES AND CONTROL OF MICRORNAS SUGGEST MAJOR INFLUENCES ON GENE EXPRESSION, IN THE ABSENCE OF PERMANENT DNA CHANGES. GENOME-WIDE ASSOCIATION STUDIES HAVE HIGHLIGHTED NEW PATHWAYS SUCH AS JAK/STAT SIGNALING THAT PROFOUNDLY INFLUENCE GENOMIC INSTABILITY AND RESPONSES TO DIETARY MUTAGENS. WITH IMPROVED METHODOLOGIES FOR DNA SEQUENCING AND EPIGENETIC CHANGES, IT IS TIME TO APPLY MORE SOPHISTICATED APPROACHES TO RECOGNIZING AND PROVING THE ROLE OF DIET AS A PRIMARY MODULATOR OF MUTAGENESIS IN HUMANS. 2010 5 2026 31 EPIGENETIC CHANGES IN BONE MARROW PROGENITOR CELLS INFLUENCE THE INFLAMMATORY PHENOTYPE AND ALTER WOUND HEALING IN TYPE 2 DIABETES. CLASSICALLY ACTIVATED (M1) MACROPHAGES ARE KNOWN TO PLAY A ROLE IN THE DEVELOPMENT OF CHRONIC INFLAMMATION ASSOCIATED WITH IMPAIRED WOUND HEALING IN TYPE 2 DIABETES (T2D); HOWEVER, THE MECHANISM RESPONSIBLE FOR THE DOMINANT PROINFLAMMATORY (M1) MACROPHAGE PHENOTYPE IN T2D WOUNDS IS UNKNOWN. SINCE EPIGENETIC ENZYMES CAN DIRECT MACROPHAGE PHENOTYPES, WE ASSESSED THE ROLE OF HISTONE METHYLATION IN BONE MARROW (BM) STEM/PROGENITOR CELLS IN THE PROGRAMMING OF MACROPHAGES TOWARD A PROINFLAMMATORY PHENOTYPE. WE HAVE FOUND THAT A REPRESSIVE HISTONE METHYLATION MARK, H3K27ME3, IS DECREASED AT THE PROMOTER OF THE IL-12 GENE IN BM PROGENITORS AND THIS EPIGENETIC SIGNATURE IS PASSED DOWN TO WOUND MACROPHAGES IN A MURINE MODEL OF GLUCOSE INTOLERANCE (DIET-INDUCED OBESE). THESE EPIGENETICALLY "PREPROGRAMMED" MACROPHAGES RESULT IN POISED MACROPHAGES IN PERIPHERAL TISSUE AND NEGATIVELY IMPACT WOUND REPAIR. WE FOUND THAT IN DIABETIC CONDITIONS THE H3K27 DEMETHYLASE JMJD3 DRIVES IL-12 PRODUCTION IN MACROPHAGES AND THAT IL-12 PRODUCTION CAN BE MODULATED BY INHIBITING JMJD3. USING HUMAN T2D TISSUE AND MURINE MODELS, WE HAVE IDENTIFIED A PREVIOUSLY UNRECOGNIZED MECHANISM BY WHICH MACROPHAGES ARE PROGRAMMED TOWARD A PROINFLAMMATORY PHENOTYPE, ESTABLISHING A PATTERN OF UNRESTRAINED INFLAMMATION ASSOCIATED WITH NONHEALING WOUNDS. HENCE, HISTONE DEMETHYLASE INHIBITOR-BASED THERAPY MAY REPRESENT A NOVEL TREATMENT OPTION FOR DIABETIC WOUNDS. 2015 6 693 28 BREAKING BOUNDARIES: PAN BETI DISRUPT 3D CHROMATIN STRUCTURE, BD2-SELECTIVE BETI ARE STRICTLY EPIGENETIC TRANSCRIPTIONAL REGULATORS. BACKGROUND: BROMODOMAIN AND EXTRATERMINAL PROTEINS (BETS) ARE MORE THAN JUST EPIGENETIC REGULATORS OF TRANSCRIPTION. HERE WE HIGHLIGHT A NEW ROLE FOR THE BET PROTEIN BRD4 IN THE MAINTENANCE OF HIGHER ORDER CHROMATIN STRUCTURE AT TOPOLOGICALLY ASSOCIATING DOMAIN BOUNDARIES (TADBS). BD2-SELECTIVE AND PAN (NON-SELECTIVE) BET INHIBITORS (BETI) DIFFERENTIALLY SUPPORT CHROMATIN STRUCTURE, SELECTIVELY AFFECTING TRANSCRIPTION AND CELL VIABILITY. METHODS: USING RNA-SEQ AND BRD4 CHIP-SEQ, THE DIFFERENTIAL EFFECT OF BETI TREATMENT ON THE TRANSCRIPTOME AND BRD4 CHROMATIN OCCUPANCY OF HUMAN AORTIC ENDOTHELIAL CELLS FROM DIABETIC PATIENTS (DHAECS) STIMULATED WITH TNFALPHA WAS EVALUATED. CHROMATIN DECONDENSATION AND DNA FRAGMENTATION WAS ASSESSED BY IMMUNOFLUORESCENCE IMAGING AND QUANTIFICATION. KEY DHAEC FINDINGS WERE VERIFIED IN PROLIFERATING MONOCYTE-LIKE THP-1 CELLS USING REAL TIME-PCR, BRD4 CO-IMMUNOPRECIPITATION STUDIES, WESTERN BLOTS, PROLIFERATION AND APOPTOSIS ASSAYS. FINDINGS: WE DISCOVERED THAT 1) BRD4 CO-LOCALIZES WITH YING-YANG 1 (YY1) AT TADBS, CRITICAL CHROMATIN STRUCTURE COMPLEXES PROXIMAL TO MANY DNA REPAIR GENES. 2) BD2-SELECTIVE BETI ENRICH BRD4/YY1 ASSOCIATIONS, WHILE PAN-BETI DO NOT. 3) FAILURE TO SUPPORT CHROMATIN STRUCTURES THROUGH BRD4/YY1 ENRICHMENT INHIBITS DNA REPAIR GENE TRANSCRIPTION, WHICH INDUCES DNA DAMAGE RESPONSES, AND CAUSES WIDESPREAD CHROMATIN DECONDENSATION, DNA FRAGMENTATION, AND APOPTOSIS. 4) BD2-SELECTIVE BETI MAINTAIN HIGH ORDER CHROMATIN STRUCTURE AND CELL VIABILITY, WHILE REDUCING DELETERIOUS PRO-INFLAMMATORY TRANSCRIPTION. INTERPRETATION: BRD4 PLAYS A PREVIOUSLY UNRECOGNIZED ROLE AT TADBS. BETI DIFFERENTIALLY IMPACT TADB STABILITY. OUR RESULTS PROVIDE TRANSLATIONAL INSIGHT FOR THE DEVELOPMENT OF BETI AS THERAPEUTICS FOR A RANGE OF DISEASES INCLUDING CVD, CHRONIC KIDNEY DISEASE, CANCER, AND COVID-19. 2022 7 2739 27 EXPOSURE TO AIR POLLUTION DISRUPTS CIRCADIAN RHYTHM THROUGH ALTERATIONS IN CHROMATIN DYNAMICS. 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