1 594 117 BET PROTEIN INHIBITOR JQ1 MODULATES MITOCHONDRIAL DYSFUNCTION AND OXIDATIVE STRESS INDUCED BY CHRONIC KIDNEY DISEASE. AMONG THE MECHANISMS INVOLVED IN THE PROGRESSION OF KIDNEY DISEASE, MITOCHONDRIAL DYSFUNCTION HAS SPECIAL RELEVANCE. EPIGENETIC DRUGS SUCH AS INHIBITORS OF EXTRA-TERMINAL DOMAIN PROTEINS (IBET) HAVE SHOWN BENEFICIAL EFFECTS IN EXPERIMENTAL KIDNEY DISEASE, MAINLY BY INHIBITING PROLIFERATIVE AND INFLAMMATORY RESPONSES. THE IMPACT OF IBET ON MITOCHONDRIAL DAMAGE WAS EXPLORED IN IN VITRO STUDIES IN RENAL CELLS STIMULATED WITH TGF-BETA1 AND IN VIVO IN MURINE UNILATERAL URETERAL OBSTRUCTION (UUO) MODEL OF PROGRESSIVE KIDNEY DAMAGE. IN VITRO, JQ1 PRETREATMENT PREVENTED THE TGF-BETA1-INDUCED DOWNREGULATION OF COMPONENTS OF THE OXIDATIVE PHOSPHORYLATION CHAIN (OXPHOS), SUCH AS CYTOCHROME C AND CV-ATP5A IN HUMAN PROXIMAL TUBULAR CELLS. IN ADDITION, JQ1 ALSO PREVENTED THE ALTERED MITOCHONDRIAL DYNAMICS BY AVOIDING THE INCREASE IN THE DRP-1 FISSION FACTOR. IN UUO MODEL, RENAL GENE EXPRESSION LEVELS OF CYTOCHROME C AND CV-ATP5A AS WELL AS PROTEIN LEVELS OF CYTOCHROME C WERE REDUCED THESE CHANGES WERE PREVENTED BY JQ1 ADMINISTRATION. IN ADDITION, JQ1 DECREASED PROTEIN LEVELS OF THE DRP1 FISSION PROTEIN AND INCREASED THE OPA-1 FUSION PROTEIN, RESTORING MITOCHONDRIAL DYNAMICS. MITOCHONDRIA ALSO PARTICIPATE IN THE MAINTENANCE OF REDOX BALANCE. JQ1 RESTORED THE GENE EXPRESSION OF ANTIOXIDANT PROTEINS, SUCH AS CATALASE AND HEME OXYGENASE 1 IN TGF-BETA1-STIMULATED HUMAN PROXIMAL TUBULAR CELLS AND IN MURINE OBSTRUCTED KIDNEYS. INDEED, IN TUBULAR CELLS, JQ1 DECREASED ROS PRODUCTION INDUCED BY STIMULATION WITH TGF-BETA1, AS EVALUATED BY MITOSOXTM. IBETS, SUCH AS JQ1, IMPROVE MITOCHONDRIAL DYNAMICS, FUNCTIONALITY, AND OXIDATIVE STRESS IN KIDNEY DISEASE. 2023 2 592 27 BET BROMODOMAIN PROTEINS REGULATE TRANSCRIPTIONAL REPROGRAMMING IN GENETIC DILATED CARDIOMYOPATHY. THE BROMODOMAIN AND EXTRATERMINAL (BET) FAMILY COMPRISES EPIGENETIC READER PROTEINS THAT ARE IMPORTANT REGULATORS OF INFLAMMATORY AND HYPERTROPHIC GENE EXPRESSION IN THE HEART. WE PREVIOUSLY IDENTIFIED THE ACTIVATION OF PROINFLAMMATORY GENE NETWORKS AS A KEY EARLY DRIVER OF DILATED CARDIOMYOPATHY (DCM) IN TRANSGENIC MICE EXPRESSING A MUTANT FORM OF PHOSPHOLAMBAN (PLNR9C) - A GENETIC CAUSE OF DCM IN HUMANS. WE HYPOTHESIZED THAT BETS COACTIVATE THIS INFLAMMATORY PROCESS, REPRESENTING A CRITICAL NODE IN THE PROGRESSION OF DCM. TO TEST THIS HYPOTHESIS, WE TREATED PLNR9C OR AGE-MATCHED WT MICE LONGITUDINALLY WITH THE SMALL MOLECULE BET BROMODOMAIN INHIBITOR JQ1 OR VEHICLE. BET INHIBITION ABROGATED ADVERSE CARDIAC REMODELING, REDUCED CARDIAC FIBROSIS, AND PROLONGED SURVIVAL IN PLNR9C MICE BY INHIBITING EXPRESSION OF PROINFLAMMATORY GENE NETWORKS AT ALL STAGES OF DISEASE. SPECIFICALLY, JQ1 HAD PROFOUND EFFECTS ON PROINFLAMMATORY GENE NETWORK EXPRESSION IN CARDIAC FIBROBLASTS, WHILE HAVING LITTLE EFFECT ON GENE EXPRESSION IN CARDIOMYOCYTES. CARDIAC FIBROBLAST PROLIFERATION WAS ALSO SUBSTANTIALLY REDUCED BY JQ1. MECHANISTICALLY, WE DEMONSTRATED THAT BRD4 SERVES AS A DIRECT AND ESSENTIAL REGULATOR OF NF-KAPPAB-MEDIATED PROINFLAMMATORY GENE EXPRESSION IN CARDIAC FIBROBLASTS. SUPPRESSING PROINFLAMMATORY GENE EXPRESSION VIA BET BROMODOMAIN INHIBITION COULD BE A NOVEL THERAPEUTIC STRATEGY FOR CHRONIC DCM IN HUMANS. 2020 3 595 29 BET PROTEINS REGULATE EXPRESSION OF OSR1 IN EARLY KIDNEY DEVELOPMENT. IN UTERO RENAL DEVELOPMENT IS SUBJECT TO MATERNAL METABOLIC AND ENVIRONMENTAL INFLUENCES AFFECTING LONG-TERM RENAL FUNCTION AND THE RISK OF DEVELOPING CHRONIC KIDNEY FAILURE AND CARDIOVASCULAR DISEASE. EPIGENETIC PROCESSES HAVE BEEN IMPLICATED IN THE ORCHESTRATION OF RENAL DEVELOPMENT AND PRENATAL PROGRAMMING OF NEPHRON NUMBER. HOWEVER, THE ROLE OF MANY EPIGENETIC MODIFIERS FOR KIDNEY DEVELOPMENT IS STILL UNCLEAR. BROMODOMAIN AND EXTRA-TERMINAL DOMAIN (BET) PROTEINS ACT AS HISTONE ACETYLATION READER MOLECULES AND PROMOTE GENE TRANSCRIPTION. BET FAMILY MEMBERS BRD2, BRD3 AND BRD4 ARE EXPRESSED IN THE NEPHROGENIC ZONE DURING KIDNEY DEVELOPMENT. HERE, THE EFFECT OF THE BET INHIBITOR JQ1 ON RENAL DEVELOPMENT IS EVALUATED. INHIBITION OF BET PROTEINS VIA JQ1 LEADS TO REDUCED GROWTH OF METANEPHRIC KIDNEY CULTURES, LOSS OF THE NEPHRON PROGENITOR CELL POPULATION, AND PREMATURE AND DISTURBED NEPHRON DIFFERENTIATION. GENE EXPRESSION OF KEY NEPHRON PROGENITOR TRANSCRIPTION FACTOR OSR1 IS DOWNREGULATED AFTER 24 H BET INHIBITION, WHILE LHX1 AND PAX8 EXPRESSION IS INCREASED. MINING OF BRD4 CHIP-SEQ AND GENE EXPRESSION DATA IDENTIFY OSR1 AS A KEY FACTOR REGULATED BY BRD4-CONTROLLED GENE ACTIVATION. INHIBITION OF BRD4 BY BET INHIBITOR JQ1 LEADS TO DOWNREGULATION OF OSR1, THEREBY CAUSING A DISTURBANCE IN THE BALANCE OF NEPHRON PROGENITOR CELL SELF-RENEWAL AND PREMATURE DIFFERENTIATION OF THE NEPHRON, WHICH ULTIMATELY LEADS TO KIDNEY HYPOPLASIA AND DISTURBED NEPHRON DEVELOPMENT. THIS RAISES QUESTIONS ABOUT THE POTENTIAL TERATOGENIC EFFECTS OF BET INHIBITORS FOR EMBRYONIC DEVELOPMENT. IN SUMMARY, OUR WORK HIGHLIGHTS THE ROLE OF BET PROTEINS FOR PRENATAL PROGRAMMING OF NEPHROGENESIS AND IDENTIFIES OSR1 AS A POTENTIAL TARGET OF BET PROTEINS. 2021 4 3527 22 IL-6 ENHANCES THE NUCLEAR TRANSLOCATION OF DNA CYTOSINE-5-METHYLTRANSFERASE 1 (DNMT1) VIA PHOSPHORYLATION OF THE NUCLEAR LOCALIZATION SEQUENCE BY THE AKT KINASE. THE EPIGENETIC PROGRAMMING OF GENOMIC DNA IS ACCOMPLISHED, IN PART, BY SEVERAL DNA CYTOSINE-5-METHYLTRANSFERASES THAT ACT BY COVALENTLY MODIFYING CYTOSINES WITH THE ADDITION OF A METHYL GROUP. THIS COVALENT MODIFICATION IS MAINTAINED BY THE DNA CYTOSINE-5-METHYLTRANSFERASE-1 ENZYME (DNMT1), WHICH IS CAPABLE OF ACTING IN CONCERT WITH OTHER SIMILAR ENZYMES TO SILENCE IMPORTANT TUMOR SUPPRESSOR GENES. IL-6 IS A MULTIFUNCTIONAL MEDIATOR OF INFLAMMATION, ACTING THROUGH SEVERAL MAJOR SIGNALING CASCADES, INCLUDING THE PHOSPHATIDYLINOSITOL-3-KINASE PATHWAY (PI-3-K), WHICH ACTIVATES PROTEIN KINASE B (AKT/PKB) DOWNSTREAM. HERE, WE SHOW THAT THE SUBCELLULAR LOCALIZATION OF DNMT1 CAN BE ALTERED BY THE ADDITION OF IL-6, INCREASING THE RATE OF NUCLEAR TRANSLOCATION OF THE ENZYME FROM THE CYTOSOLIC COMPARTMENT. THE MECHANISM OF NUCLEAR TRANSLOCATION OF DNMT1 IS GREATLY ENHANCED BY PHOSPHORYLATION OF THE DNMT1 NUCLEAR LOCALIZATION SIGNAL (NLS) BY PKB/AKT KINASE. MUTAGENIC ALTERATION OF THE TWO AKT TARGET AMINO ACIDS WITHIN THE NLS RESULTS IN A MAJOR LOSS OF DNMT1 NUCLEAR TRANSLOCATION, WHILE THE CREATION OF A "PHOSPHO-MIMIC" AMINO ACID (MUTATION TO ACIDIC RESIDUES) RESTORES THIS COMPARTMENTATION ABILITY. THESE OBSERVATIONS SUGGEST AN INTERESTING HYPOTHESIS REGARDING HOW MEDIATORS OF CHRONIC INFLAMMATION MAY DISTURB THE DELICATE BALANCE OF CELLULAR COMPARTMENTALIZATION OF IMPORTANT PROTEINS, AND REVEALS A POTENTIAL MECHANISM FOR THE INDUCTION OR ENHANCEMENT OF TUMOR GROWTH VIA ALTERATION OF THE COMPONENTS INVOLVED IN THE EPIGENETIC PROGRAMMING OF A CELL. 2007 5 2002 18 EPIGENETIC AND POST-TRANSCRIPTIONAL REPRESSION SUPPORT METABOLIC SUPPRESSION IN CHRONICALLY HYPOXIC GOLDFISH. GOLDFISH ENTER A HYPOMETABOLIC STATE TO SURVIVE CHRONIC HYPOXIA. WE RECENTLY DESCRIBED TISSUE-SPECIFIC CONTRIBUTIONS OF MEMBRANE LIPID COMPOSITION REMODELING AND MITOCHONDRIAL FUNCTION TO METABOLIC SUPPRESSION ACROSS DIFFERENT GOLDFISH TISSUES. HOWEVER, THE MOLECULAR AND ESPECIALLY EPIGENETIC FOUNDATIONS OF HYPOXIA TOLERANCE IN GOLDFISH UNDER METABOLIC SUPPRESSION ARE NOT WELL UNDERSTOOD. HERE WE SHOW THAT COMPONENTS OF THE MOLECULAR OXYGEN-SENSING MACHINERY ARE ROBUSTLY ACTIVATED ACROSS TISSUES IRRESPECTIVE OF HYPOXIA DURATION. INDUCTION OF GENE EXPRESSION OF ENZYMES INVOLVED IN DNA METHYLATION TURNOVER AND MICRORNA BIOGENESIS SUGGEST A ROLE FOR EPIGENETIC TRANSCRIPTIONAL AND POST-TRANSCRIPTIONAL SUPPRESSION OF GENE EXPRESSION IN THE HYPOXIA-ACCLIMATED BRAIN. CONVERSELY, MECHANISTIC TARGET OF RAPAMYCIN-DEPENDENT TRANSLATIONAL MACHINERY ACTIVITY IS NOT REDUCED IN LIVER AND WHITE MUSCLE, SUGGESTING THIS PATHWAY DOES NOT CONTRIBUTE TO LOWERING CELLULAR ENERGY EXPENDITURE. FINALLY, MOLECULAR EVIDENCE SUPPORTS PREVIOUSLY REPORTED CHRONIC HYPOXIA-DEPENDENT CHANGES IN MEMBRANE CHOLESTEROL, LIPID METABOLISM AND MITOCHONDRIAL FUNCTION VIA CHANGES IN TRANSCRIPTS INVOLVED IN CHOLESTEROL BIOSYNTHESIS, BETA-OXIDATION, AND MITOCHONDRIAL FUSION IN MULTIPLE TISSUES. OVERALL, THIS STUDY SHOWS THAT CHRONIC HYPOXIA ROBUSTLY INDUCES EXPRESSION OF OXYGEN-SENSING MACHINERY ACROSS TISSUES, INDUCES REPRESSIVE TRANSCRIPTIONAL AND POST-TRANSCRIPTIONAL EPIGENETIC MARKS ESPECIALLY IN THE CHRONIC HYPOXIA-ACCLIMATED BRAIN AND SUPPORTS A ROLE FOR MEMBRANE REMODELING AND MITOCHONDRIAL FUNCTION AND DYNAMICS IN PROMOTING METABOLIC SUPPRESSION. 2022 6 3193 33 HDAC INHIBITION REGULATES OXIDATIVE STRESS IN CD4(+)THELPER CELLS OF CHRONIC OBSTRUCTIVE PULMONARY DISEASE AND NON-SMALL CELL LUNG CANCER PATIENTS VIA MITOCHONDRIAL TRANSCRIPTION FACTOR A (MTTFA) MODULATING NF-KAPPAB/HIF1ALPHA AXIS. HISTONE DEACETYLASES (HDACS) PLAY A CRUCIAL ROLE IN THE EPIGENETIC REGULATION OF GENE EXPRESSION BY REMODELLING CHROMATIN. ISOENZYMES OF THE HDAC FAMILY EXHIBIT ABERRANT REGULATION IN A WIDE VARIETY OF CANCERS AS WELL AS SEVERAL INFLAMMATORY LUNG DISORDERS LIKE CHRONIC OBSTRUCTIVE PULMONARY DISEASE (COPD). INHIBITION OF HDACS IS A POTENTIAL THERAPEUTIC STRATEGY THAT COULD BE USED TO REVERSE EPIGENETIC MODIFICATION. TRICHOSTATIN A (TSA), A POWERFUL HISTONE DEACETYLASE (HDAC) INHIBITOR, HAS ANTI-CANCER EFFECTS IN NUMEROUS CANCER TYPES. HOWEVER, IT IS NOT YET APPARENT HOW HDAC INHIBITORS AFFECT HUMAN NON-SMALL CELL LUNG CANCER CELLS (NSCLC) AND COPD. THIS STUDY AIMS TO INVESTIGATE TSA'S ROLE IN RESTORING MITOCHONDRIAL DYSFUNCTION AND ITS EFFECT ON HYPOXIA AND INFLAMMATION IN CD4(+)T CELLS OBTAINED FROM PATIENTS WITH COPD AND LUNG CANCER. AS A RESULT OF TREATMENT WITH TSA, THERE IS A REDUCTION IN THE EXPRESSION OF INFLAMMATORY CYTOKINES AND A DECREASED ENRICHMENT OF TRANSCRIPTIONAL FACTORS ASSOCIATED WITH INFLAMMATION AT VEGFA GENE LOCI. WE HAVE SEEN A SUBSTANTIAL DECREASE IN THE EXPRESSION OF NF-KAPPAB AND HIF1ALPHA, WHICH ARE THE CRITICAL MEDIATORS OF INFLAMMATION AND HYPOXIA, RESPECTIVELY. FOLLOWING TSA TREATMENT, MTTFA EXPRESSION WAS INCREASED, FACILITATING PATIENTS WITH COPD AND NSCLC IN THE RECOVERY OF THEIR DYSFUNCTIONAL MITOCHONDRIA. FURTHERMORE, WE HAVE DISCOVERED THAT TSA TREATMENT IN PATIENTS WITH COPD AND NSCLC MAY LEAD TO IMMUNOPROTECTIVE NESS BY INDUCING TH1NESS. OUR FINDING GIVES A NEW INSIGHT INTO THE EXISTING BODY OF KNOWLEDGE REGARDING TSA-BASED THERAPEUTIC METHODS AND HIGHLIGHTS THE NECESSITY OF EPIGENETIC THERAPY FOR THESE DEVASTATING LUNG DISORDERS. 2023 7 4582 35 N-TERMINAL BET BROMODOMAIN INHIBITORS DISRUPT A BRD4-P65 INTERACTION AND REDUCE INDUCIBLE NITRIC OXIDE SYNTHASE TRANSCRIPTION IN PANCREATIC BETA-CELLS. CHRONIC INFLAMMATION OF PANCREATIC ISLETS IS A KEY DRIVER OF BETA-CELL DAMAGE THAT CAN LEAD TO AUTOREACTIVITY AND THE EVENTUAL ONSET OF AUTOIMMUNE DIABETES (T1D). IN THE ISLET, ELEVATED LEVELS OF PROINFLAMMATORY CYTOKINES INDUCE THE TRANSCRIPTION OF THE INDUCIBLE NITRIC OXIDE SYNTHASE (INOS) GENE, NOS2, ULTIMATELY RESULTING IN INCREASED NITRIC OXIDE (NO). EXCESSIVE OR PROLONGED EXPOSURE TO NO CAUSES BETA-CELL DYSFUNCTION AND FAILURE ASSOCIATED WITH DEFECTS IN MITOCHONDRIAL RESPIRATION. RECENT STUDIES SHOWED THAT INHIBITION OF THE BROMODOMAIN AND EXTRATERMINAL DOMAIN (BET) FAMILY OF PROTEINS, A DRUGGABLE CLASS OF EPIGENETIC READER PROTEINS, PREVENTS THE ONSET AND PROGRESSION OF T1D IN THE NON-OBESE DIABETIC MOUSE MODEL. WE HYPOTHESIZED THAT BET PROTEINS CO-ACTIVATE TRANSCRIPTION OF CYTOKINE-INDUCED INFLAMMATORY GENE TARGETS IN BETA-CELLS AND THAT SELECTIVE, CHEMOTHERAPEUTIC INHIBITION OF BET BROMODOMAINS COULD REDUCE SUCH TRANSCRIPTION. HERE, WE INVESTIGATED THE ABILITY OF BET BROMODOMAIN SMALL MOLECULE INHIBITORS TO REDUCE THE BETA-CELL RESPONSE TO THE PROINFLAMMATORY CYTOKINE INTERLEUKIN 1 BETA (IL-1BETA). BET BROMODOMAIN INHIBITION ATTENUATED IL-1BETA-INDUCED TRANSCRIPTION OF THE INFLAMMATORY MEDIATOR NOS2 AND CONSEQUENT INOS PROTEIN AND NO PRODUCTION. REDUCED NOS2 TRANSCRIPTION IS CONSISTENT WITH INHIBITION OF NF-KAPPAB FACILITATED BY DISRUPTING THE INTERACTION OF A SINGLE BET FAMILY MEMBER, BRD4, WITH THE NF-KAPPAB SUBUNIT, P65. USING RECENTLY REPORTED SELECTIVE INHIBITORS OF THE FIRST AND SECOND BET BROMODOMAINS, INHIBITION OF ONLY THE FIRST BROMODOMAIN WAS NECESSARY TO REDUCE THE INTERACTION OF BRD4 WITH P65 IN BETA-CELLS. MOREOVER, INHIBITION OF THE FIRST BROMODOMAIN WAS SUFFICIENT TO MITIGATE IL-1BETA-DRIVEN DECREASES IN MITOCHONDRIAL OXYGEN CONSUMPTION RATES AND BETA-CELL VIABILITY. BY IDENTIFYING A ROLE FOR THE INTERACTION BETWEEN BRD4 AND P65 IN CONTROLLING THE RESPONSE OF BETA-CELLS TO PROINFLAMMATORY CYTOKINES, WE PROVIDE MECHANISTIC INFORMATION ON HOW BET BROMODOMAIN INHIBITION CAN DECREASE INFLAMMATION. THESE STUDIES ALSO SUPPORT THE POTENTIAL THERAPEUTIC APPLICATION OF MORE SELECTIVE BET BROMODOMAIN INHIBITORS IN ATTENUATING BETA-CELL INFLAMMATION. 2022 8 4362 31 MIR?152 REGULATES TGF?BETA1?INDUCED EPITHELIAL?MESENCHYMAL TRANSITION BY TARGETING HPIP IN TUBULAR EPITHELIAL CELLS. RENAL FIBROSIS IS A COMMON PATHOLOGICAL FEATURE OF CHRONIC KIDNEY DISEASES, AND THEIR DEVELOPMENT AND PROGRESSION ARE INFLUENCED BY EPIGENETIC MODIFICATIONS INCLUDING ABERRANT MICRORNA (MIRNA OR MIR) EXPRESSION. MIRNAS HAVE BEEN DEMONSTRATED TO MODULATE THE AGGRESSIVENESS OF VARIOUS CANCERS AND HAVE EMERGED AS POSSIBLE THERAPEUTIC AGENTS FOR THE MANAGEMENT OF RENAL FIBROSIS. TRANSFORMING GROWTH FACTOR BETA1 (TGF?BETA1)?INDUCED EPITHELIAL?MESENCHYMAL TRANSITION (EMT) OF TUBULAR EPITHELIAL CELLS SERVES A ROLE IN THE INITIATION AND PROGRESSION OF RENAL FIBROSIS. FURTHERMORE, RECENT RESULTS INDICATED THAT THE PROGRESSION OF EMT IS REVERSIBLE. THE PRESENT STUDY AIMED TO CLARIFY THE ROLE OF MIR?152 IN EMT OF THE TUBULAR EPITHELIAL CELL LINE HK?2, STIMULATED BY TGF?BETA1, USING IN VITRO TRANSFECTION WITH A MIR?152 MIMIC AND TO FURTHER INVESTIGATE THE UNDERLYING MECHANISM OF MIR?152 ACTIVITY. IN THE PRESENT STUDY, MIR?152 EXPRESSION WAS SIGNIFICANTLY REDUCED IN TGF?BETA1?TREATED HK?2 CELLS, ACCOMPANIED BY AN INCREASED EXPRESSION OF HEMATOPOIETIC PRE?B?CELL LEUKEMIA TRANSCRIPTION FACTOR (PBX)?INTERACTING PROTEIN (HPIP). ADDITIONALLY, MIR?152 OVEREXPRESSION INHIBITED TGF?BETA1?INDUCED EMT AND SUPPRESSED HPIP EXPRESSION BY DIRECTLY TARGETING THE 3' UNTRANSLATED REGION OF HPIP IN HK?2 CELLS. FURTHERMORE, UPREGULATION OF HPIP REVERSED MIR?152?MEDIATED INHIBITORY EFFECTS ON THE EMT. COLLECTIVELY, THE RESULTS SUGGEST THAT DOWNREGULATION OF MIR?152 INITIATES THE DEDIFFERENTIATION OF RENAL TUBULES AND PROGRESSION OF RENAL FIBROSIS, WHICH MAY PROVIDE IMPORTANT TARGETS FOR PREVENTION STRATEGIES OF RENAL FIBROSIS. 2018 9 4605 30 NEGATIVE REGULATORS OF TGF-BETA1 SIGNALING IN RENAL FIBROSIS; PATHOLOGICAL MECHANISMS AND NOVEL THERAPEUTIC OPPORTUNITIES. ELEVATED EXPRESSION OF THE MULTIFUNCTIONAL CYTOKINE TRANSFORMING GROWTH FACTOR BETA1 (TGF-BETA1) IS CAUSATIVELY LINKED TO KIDNEY FIBROSIS PROGRESSION INITIATED BY DIABETIC, HYPERTENSIVE, OBSTRUCTIVE, ISCHEMIC AND TOXIN-INDUCED INJURY. THERAPEUTICALLY RELEVANT APPROACHES TO DIRECTLY TARGET THE TGF-BETA1 PATHWAY (E.G., NEUTRALIZING ANTIBODIES AGAINST TGF-BETA1), HOWEVER, REMAIN ELUSIVE IN HUMANS. TGF-BETA1 SIGNALING IS SUBJECTED TO EXTENSIVE NEGATIVE CONTROL AT THE LEVEL OF TGF-BETA1 RECEPTOR, SMAD2/3 ACTIVATION, COMPLEX ASSEMBLY AND PROMOTER ENGAGEMENT DUE TO ITS CRITICAL ROLE IN TISSUE HOMEOSTASIS AND NUMEROUS PATHOLOGIES. PROGRESSIVE KIDNEY INJURY IS ACCOMPANIED BY THE DEREGULATION (LOSS OR GAIN OF EXPRESSION) OF SEVERAL NEGATIVE REGULATORS OF THE TGF-BETA1 SIGNALING CASCADE BY MECHANISMS INVOLVING PROTEIN AND MRNA STABILITY OR EPIGENETIC SILENCING, FURTHER AMPLIFYING TGF-BETA1/SMAD3 SIGNALING AND FIBROSIS. EXPRESSION OF BONE MORPHOGENETIC PROTEINS 6 AND 7 (BMP6/7), SMAD7, SLOAN-KETTERING INSTITUTE PROTO-ONCOGENE (SKI) AND SKI-RELATED NOVEL GENE (SNON), PHOSPHATE TENSIN HOMOLOG ON CHROMOSOME 10 (PTEN), PROTEIN PHOSPHATASE MAGNESIUM/MANGANESE DEPENDENT 1A (PPM1A) AND KLOTHO ARE DRAMATICALLY DECREASED IN VARIOUS NEPHROPATHIES IN ANIMALS AND HUMANS ALBEIT WITH DIFFERENT KINETICS WHILE THE EXPRESSION OF SMURF1/2 E3 LIGASES ARE INCREASED. SUCH DEREGULATIONS FREQUENTLY INITIATE MALADAPTIVE RENAL REPAIR INCLUDING RENAL EPITHELIAL CELL DEDIFFERENTIATION AND GROWTH ARREST, FIBROTIC FACTOR (CONNECTIVE TISSUE GROWTH FACTOR (CTGF/CCN2), PLASMINOGEN ACTIVATOR INHIBITOR TYPE-1 (PAI-1), TGF-BETA1) SYNTHESIS/SECRETION, FIBROPROLIFERATIVE RESPONSES AND INFLAMMATION. THIS REVIEW ADDRESSES HOW LOSS OF THESE NEGATIVE REGULATORS OF TGF-BETA1 PATHWAY EXACERBATES RENAL LESION FORMATION AND DISCUSSES THE THERAPEUTIC VALUE IN RESTORING THE EXPRESSION OF THESE MOLECULES IN AMELIORATING FIBROSIS, THUS, PRESENTING NOVEL APPROACHES TO SUPPRESS TGF-BETA1 HYPERACTIVATION DURING CHRONIC KIDNEY DISEASE (CKD) PROGRESSION. 2021 10 6665 33 UPSTREAM AND DOWNSTREAM REGULATORS OF KLOTHO EXPRESSION IN CHRONIC KIDNEY DISEASE. KLOTHO IS A CRITICAL PROTEIN THAT PROTECTS THE KIDNEY. KLOTHO IS SEVERELY DOWNREGULATED IN CHRONIC KIDNEY DISEASE (CKD), AND ITS DEFICIENCY IS IMPLICATED IN THE PATHOGENESIS AND PROGRESSION OF CKD. CONVERSELY, AN INCREASE IN KLOTHO LEVELS RESULTS IN IMPROVED KIDNEY FUNCTION AND DELAYS CKD PROGRESSION, SUPPORTING THE NOTION THAT MODULATING KLOTHO LEVELS COULD REPRESENT A POSSIBLE THERAPEUTIC STRATEGY FOR CKD TREATMENT. NEVERTHELESS, THE REGULATORY MECHANISMS RESPONSIBLE FOR THE LOSS OF KLOTHO REMAIN ELUSIVE. PREVIOUS STUDIES HAVE DEMONSTRATED THAT OXIDATIVE STRESS, INFLAMMATION, AND EPIGENETIC MODIFICATIONS CAN MODULATE KLOTHO LEVELS. THESE MECHANISMS RESULT IN A DECREASE IN KLOTHO MRNA TRANSCRIPT LEVELS AND REDUCED TRANSLATION, THUS CAN BE GROUPED TOGETHER AS UPSTREAM REGULATORY MECHANISMS. HOWEVER, THERAPEUTIC STRATEGIES THAT AIM TO RESCUE KLOTHO LEVELS BY TARGETING THESE UPSTREAM MECHANISMS DO NOT ALWAYS RESULT IN INCREASED KLOTHO, INDICATING THE INVOLVEMENT OF OTHER REGULATORY MECHANISMS. EMERGING EVIDENCE HAS SHOWN THAT ENDOPLASMIC RETICULUM (ER) STRESS, THE UNFOLDED PROTEIN RESPONSE, AND ER-ASSOCIATED DEGRADATION ALSO AFFECT THE MODIFICATION, TRANSLOCATION, AND DEGRADATION OF KLOTHO, AND THUS ARE PROPOSED TO BE DOWNSTREAM REGULATORY MECHANISMS. HERE, WE DISCUSS THE CURRENT UNDERSTANDING OF UPSTREAM AND DOWNSTREAM REGULATORY MECHANISMS OF KLOTHO AND EXAMINE POTENTIAL THERAPEUTIC STRATEGIES TO UPREGULATE KLOTHO EXPRESSION FOR CKD TREATMENT. 2023 11 5088 33 PIPERLONGUMINE REGULATES EPIGENETIC MODULATION AND ALLEVIATES PSORIASIS-LIKE SKIN INFLAMMATION VIA INHIBITION OF HYPERPROLIFERATION AND INFLAMMATION. PSORIASIS IS AN AUTOIMMUNE SKIN DISEASE, WHERE CHRONIC IMMUNE RESPONSES DUE TO EXAGGERATED CYTOKINE SIGNALING, ABNORMAL DIFFERENTIATION, AND EVASION OF KERATINOCYTES APOPTOSIS PLAYS A CRUCIAL ROLE IN MEDIATING ABNORMAL KERATINOCYTES HYPERPROLIFERATION. FROM THE THERAPEUTIC PERSPECTIVE, THE MOLECULES WITH STRONG ANTI-PROLIFERATIVE AND ANTI-INFLAMMATORY PROPERTIES COULD HAVE TREMENDOUS RELEVANCE. IN THIS STUDY, WE DEMONSTRATED THAT PIPERLONGUMINE (PPL) TREATMENT EFFECTIVELY ABROGATED THE HYPERPROLIFERATION AND DIFFERENTIATION OF KERATINOCYTES BY INDUCING ROS-MEDIATED LATE APOPTOSIS WITH LOSS OF MITOCHONDRIAL MEMBRANE POTENTIAL. BESIDES, THE ARREST OF CELL CYCLE WAS FOUND AT SUB-G1 PHASE AS A RESULT OF DNA FRAGMENTATION. MOLECULARLY, INHIBITION OF STAT3 AND AKT SIGNALING WAS OBSERVED WITH A DECREASE IN PROLIFERATIVE MARKERS SUCH AS PCNA, KI67, AND CYCLIN D1 ALONG WITH ANTI-APOPTOTIC BCL-2 PROTEIN EXPRESSION. KERATIN 17 IS A CRITICAL REGULATOR OF KERATINOCYTE DIFFERENTIATION, AND IT WAS FOUND TO BE DOWNREGULATED WITH PPL SIGNIFICANTLY. FURTHERMORE, PROMINENT ANTI-INFLAMMATORY EFFECTS WERE OBSERVED BY INHIBITION OF LIPOPOLYSACCHARIDE (LPS)/IMIQUIMOD (IMQ)-INDUCED P65 NF-KAPPAB SIGNALING CASCADE AND STRONGLY INHIBITED THE PRODUCTION OF CYTOKINE STORM INVOLVED IN PSORIASIS-LIKE SKIN INFLAMMATION, THUS LED TO THE RESTORATION OF NORMAL EPIDERMAL ARCHITECTURE WITH REDUCTION OF EPIDERMAL HYPERPLASIA AND SPLENOMEGALY. IN ADDITION, PPL EPIGENETICALLY INHIBITED HISTONE-MODIFYING ENZYMES, WHICH INCLUDE HISTONE DEACETYLASES (HDACS) OF CLASS I (HDAC1-4) AND CLASS II (HDAC6) EVALUATED BY IMMUNOBLOTTING AND HDAC ENZYME ASSAY KIT. IN ADDITION, OUR RESULTS SHOW THAT PPL EFFECTIVELY INHIBITS THE NUCLEAR TRANSLOCATION OF P65 AND A HISTONE MODULATOR HDAC3, THUS SEQUESTERED IN THE CYTOPLASM OF MACROPHAGES. FURTHERMORE, PPL EFFECTIVELY ENHANCED THE PROTEIN-PROTEIN INTERACTIONS OF HDAC3 AND P65 WITH IKAPPABALPHA, WHICH WAS DISRUPTED BY LPS STIMULATION AND WERE EVALUATED BY CO-IP AND MOLECULAR MODELING. COLLECTIVELY, OUR FINDINGS INDICATE THAT PIPERLONGUMINE MAY SERVE AS AN ANTI-PROLIFERATIVE AND ANTI-INFLAMMATORY AGENT AND COULD SERVE AS A POTENTIAL THERAPEUTIC OPTION IN TREATING PSORIASIS. 2020 12 3207 29 HDACI: CELLULAR EFFECTS, OPPORTUNITIES FOR RESTORATIVE DENTISTRY. ACETYLATION OF HISTONE AND NON-HISTONE PROTEINS ALTERS GENE EXPRESSION AND INDUCES A HOST OF CELLULAR EFFECTS. THE ACETYLATION PROCESS IS HOMEOSTATICALLY BALANCED BY TWO GROUPS OF CELLULAR ENZYMES, HISTONE ACETYLTRANSFERASES (HATS) AND HISTONE DEACETYLASES (HDACS). HAT ACTIVITY RELAXES THE STRUCTURE OF THE HUMAN CHROMATIN, RENDERING IT TRANSCRIPTIONALLY ACTIVE, THEREBY INCREASING GENE EXPRESSION. IN CONTRAST, HDAC ACTIVITY LEADS TO GENE SILENCING. THE ENZYMATIC BALANCE CAN BE 'TIPPED' BY HISTONE DEACETYLASE INHIBITORS (HDACI), LEADING TO AN ACCUMULATION OF ACETYLATED PROTEINS, WHICH SUBSEQUENTLY MODIFY CELLULAR PROCESSES INCLUDING STEM CELL DIFFERENTIATION, CELL CYCLE, APOPTOSIS, GENE EXPRESSION, AND ANGIOGENESIS. THERE IS A VARIETY OF NATURAL AND SYNTHETIC HDACI AVAILABLE, AND THEIR PLEIOTROPIC EFFECTS HAVE CONTRIBUTED TO DIVERSE CLINICAL APPLICATIONS, NOT ONLY IN CANCER BUT ALSO IN NON-CANCER AREAS, SUCH AS CHRONIC INFLAMMATORY DISEASE, BONE ENGINEERING, AND NEURODEGENERATIVE DISEASE. INDEED, IT APPEARS THAT HDACI-MODULATED EFFECTS MAY DIFFER BETWEEN 'NORMAL' AND TRANSFORMED CELLS, PARTICULARLY WITH REGARD TO REACTIVE OXYGEN SPECIES ACCUMULATION, APOPTOSIS, PROLIFERATION, AND CELL CYCLE ARREST. THE POTENTIAL BENEFICIAL EFFECTS OF HDACI FOR HEALTH, RESULTING FROM THEIR ABILITY TO REGULATE GLOBAL GENE EXPRESSION BY EPIGENETIC MODIFICATION OF DNA-ASSOCIATED PROTEINS, ALSO OFFER POTENTIAL FOR APPLICATION WITHIN RESTORATIVE DENTISTRY, WHERE THEY MAY PROMOTE DENTAL TISSUE REGENERATION FOLLOWING PULPAL DAMAGE. 2011 13 689 40 BRD4 AS A THERAPEUTIC TARGET IN PULMONARY DISEASES. BROMODOMAIN AND EXTRA-TERMINAL DOMAIN (BET) PROTEINS ARE EPIGENETIC MODULATORS THAT REGULATE GENE TRANSCRIPTION THROUGH INTERACTING WITH ACETYLATED LYSINE RESIDUES OF HISTONE PROTEINS. BET PROTEINS HAVE MULTIPLE ROLES IN REGULATING KEY CELLULAR FUNCTIONS SUCH AS CELL PROLIFERATION, DIFFERENTIATION, INFLAMMATION, OXIDATIVE AND REDOX BALANCE, AND IMMUNE RESPONSES. AS A RESULT, BET PROTEINS HAVE BEEN FOUND TO BE ACTIVELY INVOLVED IN A BROAD RANGE OF HUMAN LUNG DISEASES INCLUDING ACUTE LUNG INFLAMMATION, ASTHMA, PULMONARY ARTERIAL HYPERTENSION, PULMONARY FIBROSIS, AND CHRONIC OBSTRUCTIVE PULMONARY DISEASE (COPD). DUE TO THE IDENTIFICATION OF SPECIFIC SMALL MOLECULAR INHIBITORS OF BET PROTEINS, TARGETING BET IN THESE LUNG DISEASES HAS BECOME AN AREA OF INCREASING INTEREST. EMERGING EVIDENCE HAS DEMONSTRATED THE BENEFICIAL EFFECTS OF BET INHIBITORS IN PRECLINICAL MODELS OF VARIOUS HUMAN LUNG DISEASES. THIS IS, IN GENERAL, LARGELY RELATED TO THE ABILITY OF BET PROTEINS TO BIND TO PROMOTERS OF GENES THAT ARE CRITICAL FOR INFLAMMATION, DIFFERENTIATION, AND BEYOND. BY MODULATING THESE CRITICAL GENES, BET PROTEINS ARE INTEGRATED INTO THE PATHOGENESIS OF DISEASE PROGRESSION. THE INTRINSIC HISTONE ACETYLTRANSFERASE ACTIVITY OF BROMODOMAIN-CONTAINING PROTEIN 4 (BRD4) IS OF PARTICULAR INTEREST, SEEMS TO ACT INDEPENDENTLY OF ITS BROMODOMAIN BINDING ACTIVITY, AND HAS IMPLICATION IN SOME CONTEXTS. IN THIS REVIEW, WE PROVIDE A BRIEF OVERVIEW OF THE RESEARCH ON BET PROTEINS WITH A FOCUS ON BRD4 IN SEVERAL MAJOR HUMAN LUNG DISEASES, THE UNDERLYING MOLECULAR MECHANISMS, AS WELL AS FINDINGS OF TARGETING BET PROTEINS USING PHARMACEUTICAL INHIBITORS IN DIFFERENT LUNG DISEASES PRECLINICALLY. 2023 14 199 24 ACTIVATED HISTONE ACETYLTRANSFERASE P300/CBP-RELATED SIGNALLING PATHWAYS MEDIATE UP-REGULATION OF NADPH OXIDASE, INFLAMMATION, AND FIBROSIS IN DIABETIC KIDNEY. ACCUMULATING EVIDENCE IMPLICATES THE HISTONE ACETYLATION-BASED EPIGENETIC MECHANISMS IN THE PATHOETIOLOGY OF DIABETES-ASSOCIATED MICRO-/MACROVASCULAR COMPLICATIONS. DIABETIC KIDNEY DISEASE (DKD) IS A PROGRESSIVE CHRONIC INFLAMMATORY MICROVASCULAR DISORDER ULTIMATELY LEADING TO GLOMERULOSCLEROSIS AND KIDNEY FAILURE. WE HYPOTHESIZED THAT HISTONE ACETYLTRANSFERASE P300/CBP MAY BE INVOLVED IN MEDIATING DIABETES-ACCELERATED RENAL DAMAGE. IN THIS STUDY, WE AIMED AT INVESTIGATING THE POTENTIAL ROLE OF P300/CBP IN THE UP-REGULATION OF RENAL NADPH OXIDASE (NOX), REACTIVE OXYGEN SPECIES (ROS) PRODUCTION, INFLAMMATION, AND FIBROSIS IN DIABETIC MICE. DIABETIC C57BL/6J MICE WERE RANDOMIZED TO RECEIVE 10 MG/KG C646, A SELECTIVE P300/CBP INHIBITOR, OR ITS VEHICLE FOR 4 WEEKS. WE FOUND THAT IN THE KIDNEY OF C646-TREATED DIABETIC MICE, THE LEVEL OF H3K27AC, AN EPIGENETIC MARK OF ACTIVE GENE EXPRESSION, WAS SIGNIFICANTLY REDUCED. PHARMACOLOGICAL INHIBITION OF P300/CBP SIGNIFICANTLY DOWN-REGULATED THE DIABETES-INDUCED ENHANCED EXPRESSION OF NOX SUBTYPES, PRO-INFLAMMATORY, AND PRO-FIBROTIC MOLECULES IN THE KIDNEY OF MICE, AND THE GLOMERULAR ROS OVERPRODUCTION. OUR STUDY PROVIDES EVIDENCE THAT THE ACTIVATION OF P300/CBP ENHANCES ROS PRODUCTION, POTENTIALLY GENERATED BY UP-REGULATED NOX, INFLAMMATION, AND THE PRODUCTION OF EXTRACELLULAR MATRIX PROTEINS IN THE DIABETIC KIDNEY. THE DATA SUGGEST THAT P300/CBP-PHARMACOLOGICAL INHIBITORS MAY BE ATTRACTIVE TOOLS TO MODULATE DIABETES-ASSOCIATED PATHOLOGICAL PROCESSES TO EFFICIENTLY REDUCE THE BURDEN OF DKD. 2021 15 19 34 5-AZACYTYDINE AND RESVERATROL REVERSE SENESCENCE AND AGEING OF ADIPOSE STEM CELLS VIA MODULATION OF MITOCHONDRIAL DYNAMICS AND AUTOPHAGY. OBESITY AND ENDOCRINE DISORDERS HAVE BECOME PREVALENT ISSUES IN THE FIELD OF BOTH HUMAN AND VETERINARY MEDICINE. EQUINE METABOLIC SYNDROME IS A COMPLEX DISORDER INVOLVING ALTERNATION IN METABOLISM AND CHRONIC SYSTEMIC INFLAMMATION. IT HAS BEEN SHOWN THAT UNFAVOURABLE MICROENVIRONMENT OF INFLAMED ADIPOSE TISSUE NEGATIVELY AFFECTS ADIPOSE STEM CELL POPULATION (ASC) RESIDING WITHIN, MARKEDLY LIMITING THEIR THERAPEUTIC POTENTIAL. ASCS(EMS) ARE CHARACTERIZED BY INCREASED SENESCENCE APOPTOSIS, EXCESSIVE ACCUMULATION OF REACTIVE OXYGEN SPECIES (ROS), MITOCHONDRIA DETERIORATION AND "AUTOPHAGIC FLUX." THE AIM OF THE PRESENT STUDY WAS TO EVALUATE WHETHER TREATMENT OF ASCS(EMS) WITH A COMBINATION OF 5-AZACYTYDINE (AZA) AND RESVERATROL (RES) WOULD REVERSE AGED PHENOTYPE OF THESE CELLS. FOR THIS REASON, WE PERFORMED THE FOLLOWING ANALYZES: MOLECULAR BIOLOGY (RT-PCR), MICROSCOPIC (IMMUNOFLUORESCENCE, TEM) AND FLOW CYTOMETRY (JC-1, ROS, KI67). WE EVALUATED THE MITOCHONDRIAL STATUS, DYNAMICS AND CLEARANCE AS WELL AS AUTOPHAGIC PATHWAYS. FURTHERMORE, WE INVESTIGATED EPIGENETIC ALTERNATIONS IN TREATED CELLS BY MEASURING THE EXPRESSION OF TET GENES AND ANALYSIS OF DNA METHYLATION STATUS. WE HAVE DEMONSTRATED THAT AZA/RES TREATMENT OF ASCS(EMS) IS ABLE TO REJUVENATE THESE CELLS BY MODULATING MITOCHONDRIAL DYNAMICS, IN PARTICULAR BY PROMOTING MITOCHONDRIAL FUSION OVER FISSION. AFTER AZA/RES TREATMENT, ASCS(EMS) WERE CHARACTERIZED BY INCREASED PROLIFERATION RATE, DECREASED APOPTOSIS AND SENESCENCE AND LOWER ROS ACCUMULATION. OUR FINDINGS OFFER A NOVEL APPROACH AND POTENTIAL TARGETS FOR THE BENEFICIAL EFFECTS OF AZA/RES IN AMELIORATING STEM CELL DYSFUNCTIONS. 2019 16 4702 33 NICOTINE-INDUCED OXIDATIVE STRESS CONTRIBUTES TO EMT AND STEMNESS DURING NEOPLASTIC TRANSFORMATION THROUGH EPIGENETIC MODIFICATIONS IN HUMAN KIDNEY EPITHELIAL CELLS. NICOTINE IS A COMPONENT OF CIGARETTE SMOKE AND MOUNTING EVIDENCE SUGGESTS TOXICITY AND CARCINOGENICITY OF TOBACCO SMOKE IN KIDNEY. CARCINOGENICITY OF NICOTINE ITSELF IN KIDNEY AND THE UNDERLYING MOLECULAR MECHANISMS ARE NOT WELL-UNDERSTOOD. HENCE, THE OBJECTIVE OF THIS STUDY WAS TO DETERMINE THE CARCINOGENIC EFFECTS OF CHRONIC NICOTINE EXPOSURE IN HK-2 HUMAN KIDNEY EPITHELIAL CELLS. THE EFFECTS OF NICOTINE EXPOSURE ON THE EXPRESSION OF GENES FOR CELLULAR REPROGRAMMING, REDOX STATUS, AND GROWTH SIGNALING PATHWAYS WERE ALSO EVALUATED TO UNDERSTAND THE MOLECULAR MECHANISMS. RESULTS REVEALED THAT CHRONIC EXPOSURE TO NICOTINE INDUCED GROWTH AND NEOPLASTIC TRANSFORMATION IN HK-2 CELLS. INCREASED LEVELS OF INTRACELLULAR REACTIVE OXYGEN SPECIES (ROS), ACQUIRED STEM CELL-LIKE SPHERE FORMATION, AND EPITHELIAL-MESENCHYMAL-TRANSITION (EMT) CHANGES WERE OBSERVED IN NICOTINE EXPOSED CELLS. TREATMENT WITH ANTIOXIDANT N-ACETYL CYSTEINE (NAC) RESULTED IN ABROGATION OF EMT AND STEMNESS IN HK-2 CELLS, INDICATING THE ROLE OF NICOTINE-INDUCED ROS IN THESE MORPHOLOGICAL CHANGES. THE RESULT ALSO SUGGESTS THAT ROS CONTROLS THE STEMNESS THROUGH REGULATION OF AKT PATHWAY DURING EARLY STAGES OF CARCINOGENESIS. ADDITIONALLY, THE EXPRESSION OF EPIGENETIC REGULATORY GENES WAS ALTERED IN NICOTINE-EXPOSED CELLS AND THE CHANGES WERE REVERSED BY NAC. THE EPIGENETIC THERAPEUTICS 5-AZA-2'-DEOXYCYTIDINE AND TRICHOSTATIN A ALSO ABROGATED THE STEMNESS. THIS SUGGESTS THE NICOTINE-INDUCED OXIDATIVE STRESS CAUSED EPIGENETIC ALTERATIONS CONTRIBUTING TO STEMNESS DURING NEOPLASTIC TRANSFORMATION. TO OUR KNOWLEDGE, THIS IS THE FIRST REPORT SHOWING THE ROS-MEDIATED EPIGENETIC MODIFICATIONS AS THE UNDERLYING MECHANISM FOR CARCINOGENICITY OF NICOTINE IN HUMAN KIDNEY EPITHELIAL CELLS. THIS STUDY FURTHER SUGGESTS THE POTENTIAL OF EPIGENETIC THERAPEUTICS FOR PHARMACOLOGICAL INTERVENTION IN NICOTINE-INDUCED KIDNEY CANCER. 2019 17 697 28 BROMODOMAIN AND EXTRATERMINAL PROTEINS AS NOVEL EPIGENETIC TARGETS FOR RENAL DISEASES. EPIGENETIC MECHANISMS, ESPECIALLY DNA METHYLATION AND HISTONE MODIFICATIONS, ARE DYNAMIC PROCESSES THAT REGULATE THE GENE EXPRESSION TRANSCRIPTIONAL PROGRAM IN NORMAL AND DISEASED STATES. THE BROMODOMAIN AND EXTRATERMINAL (BET) PROTEIN FAMILY (BRD2, BRD3, BRD4, AND BRDT) ARE EPIGENETIC READERS THAT, VIA BROMODOMAINS, REGULATE GENE TRANSCRIPTION BY BINDING TO ACETYLATED LYSINE RESIDUES ON HISTONES AND MASTER TRANSCRIPTIONAL FACTORS. EXPERIMENTAL DATA HAVE DEMONSTRATED THE INVOLVEMENT OF SOME BET PROTEINS IN MANY PATHOLOGICAL CONDITIONS, INCLUDING TUMOR DEVELOPMENT, INFECTIONS, AUTOIMMUNITY, AND INFLAMMATION. SELECTIVE BROMODOMAIN INHIBITORS ARE EPIGENETIC DRUGS THAT BLOCK THE INTERACTION BETWEEN BET PROTEINS AND ACETYLATED PROTEINS, THUS EXERTING BENEFICIAL EFFECTS. RECENT DATA HAVE DESCRIBED THE BENEFICIAL EFFECT OF BET INHIBITION ON EXPERIMENTAL RENAL DISEASES. EMERGING EVIDENCE UNDERSCORES THE IMPORTANCE OF ENVIRONMENTAL MODIFICATIONS IN THE ORIGIN OF PATHOLOGICAL FEATURES IN CHRONIC KIDNEY DISEASES (CKD). SEVERAL CELLULAR PROCESSES SUCH AS OXIDATION, METABOLIC DISORDERS, CYTOKINES, INFLAMMATION, OR ACCUMULATED UREMIC TOXINS MAY INDUCE EPIGENETIC MODIFICATIONS THAT REGULATE KEY PROCESSES INVOLVED IN RENAL DAMAGE AND IN OTHER PATHOLOGICAL CONDITIONS OBSERVED IN CKD PATIENTS. HERE, WE REVIEW HOW TARGETING BROMODOMAINS IN BET PROTEINS MAY REGULATE ESSENTIAL PROCESSES INVOLVED IN RENAL DISEASES AND IN ASSOCIATED COMPLICATIONS FOUND IN CKD PATIENTS, SUCH AS CARDIOVASCULAR DAMAGE, HIGHLIGHTING THE POTENTIAL OF EPIGENETIC THERAPEUTIC STRATEGIES AGAINST BET PROTEINS FOR CKD TREATMENT AND ASSOCIATED RISKS. 2019 18 5972 20 TET REPRESSION AND INCREASED DNMT ACTIVITY SYNERGISTICALLY INDUCE ABERRANT DNA METHYLATION. CHRONIC INFLAMMATION IS DEEPLY INVOLVED IN VARIOUS HUMAN DISORDERS, SUCH AS CANCER, NEURODEGENERATIVE DISORDERS, AND METABOLIC DISORDERS. INDUCTION OF EPIGENETIC ALTERATIONS, ESPECIALLY ABERRANT DNA METHYLATION, IS ONE OF THE MAJOR MECHANISMS, BUT HOW IT IS INDUCED IS STILL UNCLEAR. HERE, WE FOUND THAT EXPRESSION OF TET GENES, METHYLATION ERASERS, WAS DOWNREGULATED IN INFLAMED MOUSE AND HUMAN TISSUES, AND THAT THIS WAS CAUSED BY UPREGULATION OF TET-TARGETING MIRNAS SUCH AS MIR20A, MIR26B, AND MIR29C, LIKELY DUE TO ACTIVATION OF NF-KAPPAB SIGNALING DOWNSTREAM OF IL-1BETA AND TNF-ALPHA. HOWEVER, TET KNOCKDOWN INDUCED ONLY MILD ABERRANT METHYLATION. NITRIC OXIDE (NO), PRODUCED BY NOS2, ENHANCED ENZYMATIC ACTIVITY OF DNA METHYLTRANSFERASES (DNMTS), METHYLATION WRITERS, AND NO EXPOSURE INDUCED MINIMAL ABERRANT METHYLATION. IN CONTRAST, A COMBINATION OF TET KNOCKDOWN AND NO EXPOSURE SYNERGISTICALLY INDUCED ABERRANT METHYLATION, INVOLVING GENOMIC REGIONS NOT METHYLATED BY EITHER ALONE. THE RESULTS SHOWED THAT A VICIOUS COMBINATION OF TET REPRESSION, DUE TO NF-KAPPAB ACTIVATION, AND DNMT ACTIVATION, DUE TO NO PRODUCTION, IS RESPONSIBLE FOR ABERRANT METHYLATION INDUCTION IN HUMAN TISSUES. 2020 19 172 27 ABSENCE OF HDAC3 BY MATRIX STIFFNESS PROMOTES CHROMATIN REMODELING AND FIBROBLAST ACTIVATION IN IDIOPATHIC PULMONARY FIBROSIS. IDIOPATHIC PULMONARY FIBROSIS (IPF) IS A CHRONIC AND FATAL DISEASE CHARACTERIZED BY PROGRESSIVE AND IRREVERSIBLE LUNG SCARRING ASSOCIATED WITH PERSISTENT ACTIVATION OF FIBROBLASTS. EPIGENETICS COULD INTEGRATE DIVERSE MICROENVIRONMENTAL SIGNALS, SUCH AS STIFFNESS, TO DIRECT PERSISTENT FIBROBLAST ACTIVATION. HISTONE MODIFICATIONS BY DEACETYLASES (HDAC) MAY PLAY AN ESSENTIAL ROLE IN THE GENE EXPRESSION CHANGES INVOLVED IN THE PATHOLOGICAL REMODELING OF THE LUNG. PARTICULARLY, HDAC3 IS CRUCIAL FOR MAINTAINING CHROMATIN AND REGULATING GENE EXPRESSION, BUT LITTLE IS KNOWN ABOUT ITS ROLE IN IPF. IN THE STUDY, CONTROL AND IPF-DERIVED FIBROBLASTS WERE USED TO DETERMINE THE INFLUENCE OF HDAC3 ON CHROMATIN REMODELING AND GENE EXPRESSION ASSOCIATED WITH IPF SIGNATURE. ADDITIONALLY, THE CELLS WERE GROWN ON HYDROGELS TO MIMIC THE STIFFNESS OF A FIBROTIC LUNG. OUR RESULTS SHOWED A DECREASED HDAC3 IN THE NUCLEUS OF IPF FIBROBLASTS, WHICH CORRELATES WITH CHANGES IN NUCLEUS SIZE AND HETEROCHROMATIN LOSS. THE INHIBITION OF HDAC3 WITH A PHARMACOLOGICAL INHIBITOR CAUSES HYPERACETYLATION OF H3K9 AND PROVOKES AN INCREASED EXPRESSION OF COL1A1, ACTA2, AND P21. COMPARABLE RESULTS WERE FOUND IN HYDROGELS, WHERE MATRIX STIFFNESS PROMOTES THE LOSS OF NUCLEAR HDAC3 AND INCREASES THE PROFIBROTIC SIGNATURE. FINALLY, LATRUNCULIN B WAS USED TO CONFIRM THAT CHANGES BY STIFFNESS DEPEND ON THE MECHANOTRANSDUCTION SIGNALS. TOGETHER, THESE RESULTS SUGGEST THAT HDAC3 COULD BE A LINK BETWEEN EPIGENETIC MECHANISMS AND THE FIBROTIC MICROENVIRONMENT. 2023 20 593 34 BET PROTEIN INHIBITION REGULATES CYTOKINE PRODUCTION AND PROMOTES NEUROPROTECTION AFTER SPINAL CORD INJURY. BACKGROUND: SPINAL CORD INJURY (SCI) USUALLY CAUSES A DEVASTATING LIFELONG DISABILITY FOR PATIENTS. AFTER A TRAUMATIC LESION, DISRUPTION OF THE BLOOD-SPINAL CORD BARRIER INDUCES THE INFILTRATION OF MACROPHAGES INTO THE LESION SITE AND THE ACTIVATION OF RESIDENT GLIAL CELLS, WHICH RELEASE CYTOKINES AND CHEMOKINES. THESE EVENTS RESULT IN A PERSISTENT INFLAMMATION, WHICH HAS BOTH DETRIMENTAL AND BENEFICIAL EFFECTS, BUT EVENTUALLY LIMITS FUNCTIONAL RECOVERY AND CONTRIBUTES TO THE APPEARANCE OF NEUROPATHIC PAIN. BROMODOMAIN AND EXTRA-TERMINAL DOMAIN (BET) PROTEINS ARE EPIGENETIC READERS THAT REGULATE THE EXPRESSION OF INFLAMMATORY GENES BY INTERACTING WITH ACETYLATED LYSINE RESIDUES. WHILE BET INHIBITORS ARE A PROMISING THERAPEUTIC STRATEGY FOR CANCER, LITTLE IS KNOWN ABOUT THEIR IMPLICATION AFTER SCI. THUS, THE CURRENT STUDY WAS AIMED TO INVESTIGATE THE ANTI-INFLAMMATORY ROLE OF BET INHIBITORS IN THIS PATHOLOGIC CONDITION. METHODS: WE EVALUATED THE EFFECTIVENESS OF THE BET INHIBITOR JQ1 TO MODIFY MACROPHAGE REACTIVITY IN VITRO AND TO MODULATE INFLAMMATION IN A SCI MICE MODEL. WE ANALYZED THE EFFECTS OF BET INHIBITION IN PRO-INFLAMMATORY AND ANTI-INFLAMMATORY CYTOKINE PRODUCTION IN VITRO AND IN VIVO. WE DETERMINED THE EFFECTIVENESS OF BET INHIBITION IN TISSUE SPARING, INFLAMMATION, NEURONAL PROTECTION, AND BEHAVIORAL OUTCOME AFTER SCI. RESULTS: WE HAVE FOUND THAT THE BET INHIBITOR JQ1 REDUCED THE LEVELS OF PRO-INFLAMMATORY MEDIATORS AND INCREASED THE EXPRESSION OF ANTI-INFLAMMATORY CYTOKINES. A PROLONGED TREATMENT WITH JQ1 ALSO DECREASED REACTIVITY OF MICROGLIA/MACROPHAGES, ENHANCED NEUROPROTECTION AND FUNCTIONAL RECOVERY, AND ACUTELY REDUCED NEUROPATHIC PAIN AFTER SCI. CONCLUSIONS: BET PROTEIN INHIBITION IS AN EFFECTIVE TREATMENT TO REGULATE CYTOKINE PRODUCTION AND PROMOTE NEUROPROTECTION AFTER SCI. THESE NOVEL RESULTS DEMONSTRATE FOR THE FIRST TIME THAT TARGETING BET PROTEINS IS AN ENCOURAGING APPROACH FOR SCI REPAIR AND A POTENTIAL STRATEGY TO TREAT OTHER INFLAMMATORY PATHOLOGIES. 2019