1 443 112 AORTA MACROPHAGE INFLAMMATORY AND EPIGENETIC CHANGES IN A MURINE MODEL OF OBSTRUCTIVE SLEEP APNEA: POTENTIAL ROLE OF CD36. OBSTRUCTIVE SLEEP APNEA (OSA) AFFECTS 8-10% OF THE POPULATION, IS CHARACTERIZED BY CHRONIC INTERMITTENT HYPOXIA (CIH), AND CAUSALLY ASSOCIATES WITH CARDIOVASCULAR MORBIDITIES. IN CIH-EXPOSED MICE, CLOSELY MIMICKING THE CHRONICITY OF HUMAN OSA, INCREASED ACCUMULATION AND PROLIFERATION OF PRO-INFLAMMATORY METABOLIC M1-LIKE MACROPHAGES HIGHLY EXPRESSING CD36, EMERGED IN AORTA. TRANSCRIPTOMIC AND MEDIP-SEQ APPROACHES IDENTIFIED ACTIVATION OF PRO-ATHEROGENIC PATHWAYS INVOLVING A COMPLEX INTERPLAY OF HISTONE MODIFICATIONS IN FUNCTIONALLY-RELEVANT BIOLOGICAL PATHWAYS, SUCH AS INFLAMMATION AND OXIDATIVE STRESS IN AORTA MACROPHAGES. DISCONTINUATION OF CIH DID NOT ELICIT SIGNIFICANT IMPROVEMENTS IN AORTA WALL MACROPHAGE PHENOTYPE. HOWEVER, CIH-INDUCED AORTA CHANGES WERE ABSENT IN CD36 KNOCKOUT MICE, OUR RESULTS PROVIDE MECHANISTIC INSIGHTS SHOWING THAT CIH EXPOSURES DURING SLEEP IN ABSENCE OF CONCURRENT PRO-ATHEROGENIC SETTINGS (I.E., GENETIC PROPENSITY OR DIETARY MANIPULATION) LEAD TO THE RECRUITMENT OF CD36(+)(HIGH) MACROPHAGES TO THE AORTIC WALL AND TRIGGER ATHEROGENESIS. FURTHERMORE, LONG-TERM CIH-INDUCED CHANGES MAY NOT BE REVERSIBLE WITH USUAL OSA TREATMENT. 2017 2 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 3 4542 39 MURINE MODELS OF SLEEP APNEA: FUNCTIONAL IMPLICATIONS OF ALTERED MACROPHAGE POLARITY AND EPIGENETIC MODIFICATIONS IN ADIPOSE AND VASCULAR TISSUES. OBSTRUCTIVE SLEEP APNEA (OSA) IS A HIGHLY PREVALENT DISEASE ACROSS THE LIFESPAN, IS CHARACTERIZED BY CHRONIC INTERMITTENT HYPOXIA AND SLEEP FRAGMENTATION, AND HAS BEEN INDEPENDENTLY ASSOCIATED WITH SUBSTANTIAL CARDIOMETABOLIC MORBIDITY. HOWEVER, THE REVERSIBILITY OF END-ORGAN MORBIDITY WITH TREATMENT IS NOT ALWAYS APPARENT, SUGGESTING THAT BOTH TISSUE REMODELING AND EPIGENETIC MECHANISMS MAY BE OPERATIONALLY INVOLVED. HERE, WE REVIEW THE CUMULATIVE EVIDENCE FOCUSED AROUND MURINE MODELS OF OSA TO ILLUSTRATE THE TEMPORAL DEPENDENCIES OF CARDIOMETABOLIC DYSFUNCTION AND ITS REVERSIBILITY, AND MORE PARTICULARLY TO DISCUSS THE CRITICAL CONTRIBUTIONS OF TISSUE MACROPHAGES TO ADIPOSE TISSUE INSULIN RESISTANCE AND VASCULAR ATHEROGENESIS. IN ADDITION, WE DESCRIBE INITIAL FINDINGS POTENTIALLY IMPLICATING EPIGENETIC ALTERATIONS IN BOTH THE EMERGENCE OF THE CARDIOMETABOLIC MORBIDITY OF OSA, AND IN ITS REVERSIBILITY WITH TREATMENT. WE ANTICIPATE THAT IMPROVED UNDERSTANDING OF MACROPHAGE BIOLOGY AND EPIGENETICS IN THE CONTEXT OF INTERMITTENT HYPOXIA AND SLEEP FRAGMENTATION WILL LEAD TO DISCOVERY OF NOVEL THERAPEUTIC TARGETS AND IMPROVED CARDIOVASCULAR AND METABOLIC OUTCOMES IN OSA. 2018 4 4489 27 MONOCYTE AND MACROPHAGE IMMUNOMETABOLISM IN ATHEROSCLEROSIS. ATHEROSCLEROSIS IS CHARACTERIZED BY CHRONIC LOW GRADE INFLAMMATION OF ARTERIES THAT RESULTS IN THE DEVELOPMENT OF LIPID DENSE PLAQUES. CHRONIC INFLAMMATION INDUCED BY WESTERN-TYPE DIET IS ASSOCIATED WITH THE RISK OF DEVELOPING ATHEROSCLEROSIS, AND NEW INSIGHTS SHED LIGHT ON THE IMPORTANCE OF METABOLIC AND FUNCTIONAL REPROGRAMMING IN MONOCYTES AND MACROPHAGES FOR PROGRESSION OF ATHEROSCLEROSIS. THIS REVIEW AIMS TO PROVIDE AN OVERVIEW OF OUR CURRENT UNDERSTANDING INTO HOW THE METABOLIC REPROGRAMMING OF GLUCOSE, CHOLESTEROL, FATTY ACID, AND AMINO ACID METABOLISM IN MACROPHAGES CONTRIBUTES TO INFLAMMATION DURING ATHEROSCLEROSIS. RECENT INSIGHTS SUGGEST THAT TRANSCRIPTIONAL AND EPIGENETIC ADAPTATION WITHIN INNATE IMMUNE CELLS (TERMED TRAINED IMMUNITY) PLAY AN IMPORTANT ROLE IN THE PATHOGENESIS OF ATHEROSCLEROSIS. WE PROPOSE THAT METABOLIC CHANGES INDUCED BY PRO-ATHEROGENIC LIPOPROTEINS PARTLY MEDIATE THESE CHANGES IN TRAINED MACROPHAGES. FINALLY, WE DISCUSS THE POSSIBILITY OF MANIPULATING CELLULAR METABOLISM OF IMMUNE CELLS FOR TARGETED THERAPEUTIC INTERVENTION AGAINST ATHEROSCLEROSIS. 2018 5 5544 29 ROLE OF EPIGENETIC ABNORMALITIES AND INTERVENTION IN OBSTRUCTIVE SLEEP APNEA TARGET ORGANS. OBSTRUCTIVE SLEEP APNEA (OSA) IS A COMMON CONDITION THAT HAS CONSIDERABLE IMPACTS ON HUMAN HEALTH. EPIGENETICS HAS BECOME A RAPIDLY DEVELOPING AND EXCITING AREA IN BIOLOGY, AND IT IS DEFINED AS HERITABLE ALTERATIONS IN GENE EXPRESSION AND HAS REGULATORY EFFECTS ON DISEASE PROGRESSION. HOWEVER, THE PUBLISHED LITERATURE THAT IS INTEGRATING BOTH OF THEM IS NOT SUFFICIENT. THE PURPOSE OF THIS ARTICLE IS TO EXPLORE THE RELATIONSHIP BETWEEN OSA AND EPIGENETICS AND TO OFFER BETTER DIAGNOSTIC METHODS AND TREATMENT OPTIONS. EPIGENETIC MODIFICATIONS MAINLY MANIFEST AS POST-TRANSLATIONAL MODIFICATIONS IN DNA AND HISTONE PROTEINS AND REGULATION OF NON-CODING RNAS. CHRONIC INTERMITTENT HYPOXIA-MEDIATED EPIGENETIC ALTERATIONS ARE INVOLVED IN THE PROGRESSION OF OSA AND DIVERSE MULTIORGAN INJURIES, INCLUDING CARDIOVASCULAR DISEASE, METABOLIC DISORDERS, PULMONARY HYPERTENSION, NEURAL DYSFUNCTION, AND EVEN TUMORS. THIS ARTICLE PROVIDES DEEPER INSIGHTS INTO THE DISEASE MECHANISM OF OSA AND POTENTIAL APPLICATIONS OF TARGETED DIAGNOSIS, TREATMENT, AND PROGNOSIS IN OSA COMPLICATIONS. 2023 6 4813 25 OBSTRUCTIVE SLEEP APNEA AND HALLMARKS OF AGING. OBSTRUCTIVE SLEEP APNEA (OSA) IS ONE OF THE MOST COMMON SLEEP DISORDERS. SINCE AGING IS A RISK FACTOR FOR OSA DEVELOPMENT, IT IS EXPECTED THAT ITS PREVALENCE WILL INCREASE WITH THE CURRENT INCREASE IN LIFE SPAN. IN RECENT YEARS, SEVERAL STUDIES HAVE SHOWN THAT OSA POTENTIALLY CONTRIBUTES TO FUNCTIONAL DECLINE, MAINLY PROMPTED BY CHRONIC INTERMITTENT HYPOXIA AND SLEEP FRAGMENTATION. HERE, WE PROPOSE THAT OSA MIGHT ANTICIPATE/AGGRAVATE AGING BY INDUCING CELLULAR AND MOLECULAR IMPAIRMENTS THAT CHARACTERIZE THE AGING PROCESS, SUCH AS STEM CELL EXHAUSTION, TELOMERE ATTRITION AND EPIGENETIC CHANGES. WE SUGGEST THAT FURTHER KNOWLEDGE ON THE IMPACT OF OSA ON AGING MECHANISMS MIGHT CONTRIBUTE TO A BETTER UNDERSTANDING OF HOW OSA MIGHT PUTATIVELY ACCELERATE AGING AND AGING-RELATED DISEASES. 2017 7 1476 24 DIVERSE EPIGENETIC REGULATIONS OF MACROPHAGES IN ATHEROSCLEROSIS. EMERGING RESEARCH ON EPIGENETICS HAS RESULTED IN MANY NOVEL DISCOVERIES IN ATHEROSCLEROSIS (AS), AN INFLAMMAGING-ASSOCIATED DISEASE CHARACTERIZED BY CHRONIC INFLAMMATION PRIMARILY DRIVEN BY MACROPHAGES. THE BULK OF EVIDENCE HAS DEMONSTRATED THE CENTRAL ROLE OF EPIGENETIC MACHINERY IN MACROPHAGE POLARIZATION TO PRO- (M1-LIKE) OR ANTI-INFLAMMATORY (M2-LIKE) PHENOTYPE. AN INCREASING NUMBER OF EPIGENETIC ALTERATIONS AND THEIR MODIFIERS INVOLVED IN REPROGRAMMING MACROPHAGES BY REGULATING DNA METHYLATION OR HISTONE MODIFICATIONS (E.G., METHYLATION, ACETYLATION, AND RECENTLY LACTYLATION) HAVE BEEN IDENTIFIED. THEY MAY ACT TO DETERMINE OR SKEW THE DIRECTION OF MACROPHAGE POLARIZATION IN AS LESIONS, THEREBY REPRESENTING A PROMISING TARGET. HERE WE DESCRIBE THE CURRENT UNDERSTANDING OF THE EPIGENETIC MACHINERY INVOLVING MACROPHAGE POLARIZATION, TO SHED LIGHT ON CHRONIC INFLAMMATION-DRIVING ONSET AND PROGRESSION OF INFLAMMAGING-ASSOCIATED DISEASES, USING AS AS A PROTOTYPIC EXAMPLE, AND DISCUSS THE CHALLENGE FOR DEVELOPING EFFECTIVE THERAPIES TARGETING THE EPIGENETIC MODIFIERS AGAINST THESE DISEASES, PARTICULARLY HIGHLIGHTING A POTENTIAL STRATEGY BASED ON EPIGENETICALLY-GOVERNED REPOLARIZATION FROM M1-LIKE TO M2-LIKE PHENOTYPE. 2022 8 4814 33 OBSTRUCTIVE SLEEP APNEA, CIRCADIAN CLOCK DISRUPTION, AND METABOLIC CONSEQUENCES. OBSTRUCTIVE SLEEP APNEA (OSA) IS A CHRONIC DISORDER CHARACTERIZED BY RECURRENT EPISODES OF APNEA AND HYPOPNEA DURING SLEEP. IT IS ASSOCIATED WITH VARIOUS CARDIOVASCULAR AND METABOLIC COMPLICATIONS, INCLUDING TYPE 2 DIABETES MELLITUS (T2DM) AND OBESITY. MANY PATHWAYS CAN BE RESPONSIBLE FOR T2DM DEVELOPMENT IN OSA PATIENTS, E.G., THOSE RELATED TO HIF-1 AND SIRT1 EXPRESSION. MOREOVER, EPIGENETIC MECHANISMS, SUCH AS MIRNA181A OR MIRNA199, ARE POSTULATED TO PLAY A PIVOTAL ROLE IN THIS LINK. IT HAS BEEN PROVEN THAT OSA INCREASES THE OCCURRENCE OF CIRCADIAN CLOCK DISRUPTION, WHICH IS ALSO A RISK FACTOR FOR METABOLIC DISEASE DEVELOPMENT. CIRCADIAN CLOCK DISRUPTION IMPAIRS THE METABOLISM OF GLUCOSE, LIPIDS, AND THE SECRETION OF BILE ACIDS. THEREFORE, OSA-INDUCED CIRCADIAN CLOCK DISRUPTION MAY BE A POTENTIAL, COMPLEX, UNDERLYING PATHWAY INVOLVED IN DEVELOPING AND EXACERBATING METABOLIC DISEASES AMONG OSA PATIENTS. THE CURRENT PAPER SUMMARIZES THE AVAILABLE INFORMATION PERTAINING TO THE RELATIONSHIP BETWEEN OSA AND CIRCADIAN CLOCK DISRUPTION IN THE CONTEXT OF POTENTIAL MECHANISMS LEADING TO METABOLIC DISORDERS. 2022 9 3436 28 HYPERGLYCEMIC MEMORY OF INNATE IMMUNE CELLS PROMOTES IN VITRO PROINFLAMMATORY RESPONSES OF HUMAN MONOCYTES AND MURINE MACROPHAGES. IT HAS BEEN WELL ESTABLISHED THAT THE PRESENCE OF DIABETES IS ACCOMPANIED BY A CHRONIC INFLAMMATORY STATE PROMOTING VARIOUS DIABETES-ASSOCIATED COMPLICATIONS. ONE POTENTIAL DRIVER OF THIS ENHANCED INFLAMMATORY STATE IN PATIENTS WITH DIABETES IS HYPERGLYCEMIA. EVEN AFTER BLOOD GLUCOSE CONTROL IS ACHIEVED, DIABETES-ASSOCIATED COMPLICATIONS PERSIST, SUGGESTING THE PRESENCE OF A "HYPERGLYCEMIC MEMORY." INNATE IMMUNE CELLS, CRITICALLY INVOLVED IN VARIOUS COMPLICATIONS ASSOCIATED WITH DIABETES, CAN BUILD NONSPECIFIC, IMMUNOLOGICAL MEMORY (TRAINED IMMUNITY) VIA EPIGENETIC REGULATION. WE EXAMINE THE POTENTIAL INVOLVEMENT OF HYPERGLYCEMIA-INDUCED TRAINED IMMUNITY IN PROMOTING INFLAMMATION. OUR RESULTS SHOW THAT HYPERGLYCEMIA INDUCES A TRAINED PHENOTYPE IN VIVO IN MICE AND IN VITRO IN HUMAN MONOCYTES, REPRESENTATIVE BY AN INCREASED TNF-ALPHA SECRETION AFTER EX VIVO STIMULATION WITH LPS. THESE EFFECTS WERE LARGELY MEDIATED BY EPIGENETIC CHANGES CONTROLLED BY THE MIXED LINEAGE LEUKEMIA (MLL) FAMILY BECAUSE TREATMENT WITH THE MLL INHIBITOR MENIN-MLL DURING THE PROCESS OF TRAINED IMMUNITY ACQUISITION REPRESSED THE PROINFLAMMATORY PHENOTYPE. COLLECTIVELY, OUR RESULTS IDENTIFY A NOVEL LINK BETWEEN HYPERGLYCEMIA AND INFLAMMATION IN INNATE IMMUNE CELLS THAT MIGHT EXPLAIN THE INCREASED PROINFLAMMATORY STATE DURING DIABETES POTENTIALLY CONTRIBUTING TO THE DEVELOPMENT OF VARIOUS DIABETES-ASSOCIATED COMPLICATIONS. 2021 10 5560 28 ROLE OF HISTONE DEACETYLASE 2 IN EPIGENETICS AND CELLULAR SENESCENCE: IMPLICATIONS IN LUNG INFLAMMAGING AND COPD. HISTONE DEACETYLASE 2 (HDAC2) IS A CLASS I HISTONE DEACETYLASE THAT REGULATES VARIOUS CELLULAR PROCESSES, SUCH AS CELL CYCLE, SENESCENCE, PROLIFERATION, DIFFERENTIATION, DEVELOPMENT, APOPTOSIS, AND GLUCOCORTICOID FUNCTION IN INHIBITING INFLAMMATORY RESPONSE. HDAC2 HAS BEEN SHOWN TO PROTECT AGAINST DNA DAMAGE RESPONSE AND CELLULAR SENESCENCE/PREMATURE AGING VIA AN EPIGENETIC MECHANISM IN RESPONSE TO OXIDATIVE STRESS. THESE PHENOMENA ARE OBSERVED IN PATIENTS WITH CHRONIC OBSTRUCTIVE PULMONARY DISEASE (COPD). HDAC2 IS POSTTRANSLATIONALLY MODIFIED BY OXIDATIVE/CARBONYL STRESS IMPOSED BY CIGARETTE SMOKE AND OXIDANTS, LEADING TO ITS REDUCTION VIA AN UBIQUITINATION-PROTEASOME DEPENDENT DEGRADATION IN LUNGS OF PATIENTS WITH COPD. IN THIS PERSPECTIVE, WE HAVE DISCUSSED THE ROLE OF HDAC2 POSTTRANSLATIONAL MODIFICATIONS AND ITS ROLE IN REGULATION OF INFLAMMATION, HISTONE/DNA EPIGENETIC MODIFICATIONS, DNA DAMAGE RESPONSE, AND CELLULAR SENESCENCE, PARTICULARLY IN INFLAMMAGING, AND DURING THE DEVELOPMENT OF COPD. WE HAVE ALSO DISCUSSED THE POTENTIAL DIRECTIONS FOR FUTURE TRANSLATIONAL RESEARCH AVENUES IN MODULATING LUNG INFLAMMAGING AND CELLULAR SENESCENCE BASED ON EPIGENETIC CHROMATIN MODIFICATIONS IN DISEASES ASSOCIATED WITH INCREASED OXIDATIVE STRESS. 2012 11 4391 32 MODERATE EXERCISE INDUCES TRAINED IMMUNITY IN MACROPHAGES. DESPITE ITS IMPORTANCE IN PROTECTING THE HOST FROM INFECTIONS AND INJURY, EXCESSIVE INFLAMMATION MAY LEAD TO SERIOUS HUMAN DISEASES INCLUDING AUTOIMMUNE DISORDERS, CARDIOVASCULAR DISEASES, DIABETES, AND CANCER. EXERCISE IS A KNOWN IMMUNOMODULATOR; HOWEVER, WHETHER EXERCISE CAUSES LONG-TERM CHANGES IN INFLAMMATORY RESPONSES AND HOW THESE CHANGES OCCUR ARE LACKING. HERE, WE SHOW THAT CHRONIC MODERATE-INTENSITY TRAINING OF MICE LEADS TO PERSISTENT METABOLIC REWIRING AND CHANGES TO CHROMATIN ACCESSIBILITY IN BONE MARROW-DERIVED MACROPHAGES (BMDMS), WHICH, IN TURN, TEMPERS THEIR INFLAMMATORY RESPONSES. WE SHOW THAT BMDMS FROM EXERCISED MICE EXHIBITED A DECREASE IN LIPOPOLYSACCHARIDE (LPS)-INDUCED NF-KAPPAB ACTIVATION AND PROINFLAMMATORY GENE EXPRESSION ALONG WITH AN INCREASE IN M2-LIKE-ASSOCIATED GENES WHEN COMPARED WITH BMDMS FROM SEDENTARY MICE. THIS WAS ASSOCIATED WITH IMPROVED MITOCHONDRIAL QUALITY AND INCREASED RELIANCE ON OXIDATIVE PHOSPHORYLATION ACCOMPANIED WITH REDUCED MITOCHONDRIAL REACTIVE OXYGEN SPECIES (ROS) PRODUCTION. MECHANISTICALLY, ASSAY FOR TRANSPOSASE-ACCESSIBLE CHROMATIN (ATAC)-SEQ ANALYSIS SHOWED CHANGES IN CHROMATIN ACCESSIBILITY OF GENES ASSOCIATED WITH INFLAMMATORY AND METABOLIC PATHWAYS. OVERALL, OUR DATA SUGGEST THAT CHRONIC MODERATE EXERCISE CAN INFLUENCE THE INFLAMMATORY RESPONSES OF MACROPHAGES BY REPROGRAMMING THEIR METABOLIC AND EPIGENETIC LANDSCAPE.NEW & NOTEWORTHY IN THIS STUDY, WE EXPLAIN HOW LONG-TERM MODERATE EXERCISE TRAINING CAN REDUCE INFLAMMATION IN MOUSE MACROPHAGES BY REPROGRAMMING THE WAY THEY SENSE AND RESPOND TO THE PRESENCE OF PATHOGENS. WE COMPLETED A THOROUGH ANALYSIS AND SHOWED THAT THESE CHANGES PERSIST IN MACROPHAGES BECAUSE EXERCISE IMPROVES THE ABILITY OF CELLS TO UTILIZE OXYGEN WITHOUT PRODUCING DAMAGING COMPOUNDS, AND CHANGES THE WAY THEY ACCESS THEIR DNA. 2023 12 1383 28 DIABETES AND ITS CARDIOVASCULAR COMPLICATIONS: POTENTIAL ROLE OF THE ACETYLTRANSFERASE P300. DIABETES HAS BEEN SHOWN TO ACCELERATE VASCULAR SENESCENCE, WHICH IS ASSOCIATED WITH CHRONIC INFLAMMATION AND OXIDATIVE STRESS, BOTH IMPLICATED IN THE DEVELOPMENT OF ENDOTHELIAL DYSFUNCTION. THIS CONDITION REPRESENTS THE INITIAL ALTERATION LINKING DIABETES TO RELATED CARDIOVASCULAR (CV) COMPLICATIONS. RECENTLY, IT HAS BEEN HYPOTHESISED THAT THE ACETYLTRANSFERASE, P300, MAY CONTRIBUTE TO ESTABLISHING AN EARLY VASCULAR SENESCENT PHENOTYPE, PLAYING A RELEVANT ROLE IN DIABETES-ASSOCIATED INFLAMMATION AND OXIDATIVE STRESS, WHICH DRIVE ENDOTHELIAL DYSFUNCTION. SPECIFICALLY, P300 CAN MODULATE VASCULAR INFLAMMATION THROUGH EPIGENETIC MECHANISMS AND TRANSCRIPTION FACTORS ACETYLATION. INDEED, IT REGULATES THE INFLAMMATORY PATHWAY BY INTERACTING WITH NUCLEAR FACTOR KAPPA-LIGHT-CHAIN-ENHANCER OF ACTIVATED B CELLS P65 SUBUNIT (NF-KAPPAB P65) OR BY INDUCING ITS ACETYLATION, SUGGESTING A CRUCIAL ROLE OF P300 AS A BRIDGE BETWEEN NF-KAPPAB P65 AND THE TRANSCRIPTIONAL MACHINERY. ADDITIONALLY, P300-MEDIATED EPIGENETIC MODIFICATIONS COULD BE UPSTREAM OF THE ACTIVATION OF INFLAMMATORY CYTOKINES, AND THEY MAY INDUCE OXIDATIVE STRESS BY AFFECTING THE PRODUCTION OF REACTIVE OXYGEN SPECIES (ROS). BECAUSE SEVERAL IN VITRO AND IN VIVO STUDIES SHED LIGHT ON THE POTENTIAL USE OF ACETYLTRANSFERASE INHIBITORS, A BETTER UNDERSTANDING OF THE MECHANISMS UNDERLYING THE ROLE OF P300 IN DIABETIC VASCULAR DYSFUNCTION COULD HELP IN FINDING NEW STRATEGIES FOR THE CLINICAL MANAGEMENT OF CV DISEASES RELATED TO DIABETES. 2023 13 5931 33 TARGETING EPIGENETIC MODIFIERS TO REPROGRAMME MACROPHAGES IN NON-RESOLVING INFLAMMATION-DRIVEN ATHEROSCLEROSIS. EPIGENOMIC AND EPIGENETIC RESEARCH HAS BEEN PROVIDING SEVERAL NEW INSIGHTS INTO A VARIETY OF DISEASES CAUSED BY NON-RESOLVING INFLAMMATION, INCLUDING CARDIOVASCULAR DISEASES. ATHEROSCLEROSIS (AS) HAS LONG BEEN RECOGNIZED AS A CHRONIC INFLAMMATORY DISEASE OF THE ARTERIAL WALLS, CHARACTERIZED BY LOCAL PERSISTENT AND STEPWISE ACCELERATING INFLAMMATION WITHOUT RESOLUTION, ALSO KNOWN AS UNCONTROLLED INFLAMMATION. THE PATHOGENESIS OF AS IS DRIVEN PRIMARILY BY HIGHLY PLASTIC MACROPHAGES VIA THEIR POLARIZATION TO PRO- OR ANTI-INFLAMMATORY PHENOTYPES AS WELL AS OTHER NOVEL SUBTYPES RECENTLY IDENTIFIED BY SINGLE-CELL SEQUENCING. ALTHOUGH EMERGING EVIDENCE HAS INDICATED THE KEY ROLE OF THE EPIGENETIC MACHINERY IN THE REGULATION OF MACROPHAGE PLASTICITY, THE INVESTIGATION OF EPIGENETIC ALTERATIONS AND MODIFIERS IN AS AND RELATED INFLAMMATION IS STILL IN ITS INFANCY. AN INCREASING NUMBER OF THE EPIGENETIC MODIFIERS (E.G. TET2, DNMT3A, HDAC3, HDAC9, JMJD3, KDM4A) HAVE BEEN IDENTIFIED IN EPIGENETIC REMODELLING OF MACROPHAGES THROUGH DNA METHYLATION OR HISTONE MODIFICATIONS (E.G. METHYLATION, ACETYLATION, AND RECENTLY LACTYLATION) IN INFLAMMATION. THESE OR MANY UNEXPLORED MODIFIERS FUNCTION TO DETERMINE OR SWITCH THE DIRECTION OF MACROPHAGE POLARIZATION VIA TRANSCRIPTIONAL REPROGRAMMING OF GENE EXPRESSION AND INTRACELLULAR METABOLIC REWIRING UPON MICROENVIRONMENTAL CUES, THEREBY REPRESENTING A PROMISING TARGET FOR ANTI-INFLAMMATORY THERAPY IN AS. HERE, WE REVIEW UP-TO-DATE FINDINGS INVOLVING THE EPIGENETIC REGULATION OF MACROPHAGES TO SHED LIGHT ON THE MECHANISM OF UNCONTROLLED INFLAMMATION DURING AS ONSET AND PROGRESSION. WE ALSO DISCUSS CURRENT CHALLENGES FOR DEVELOPING AN EFFECTIVE AND SAFE ANTI-AS THERAPY THAT TARGETS THE EPIGENETIC MODIFIERS AND PROPOSE A POTENTIAL ANTI-INFLAMMATORY STRATEGY THAT REPOLARIZES MACROPHAGES FROM PRO- TO ANTI-INFLAMMATORY PHENOTYPES. 2021 14 2532 26 EPIGENETICS IN ATHEROSCLEROSIS AND INFLAMMATION. ATHEROSCLEROSIS IS A MULTIFACTORIAL DISEASE WITH A SEVERE BURDEN ON WESTERN SOCIETY. RECENT INSIGHTS INTO THE PATHOGENESIS OF ATHEROSCLEROSIS UNDERSCORE THE IMPORTANCE OF CHRONIC INFLAMMATION IN BOTH THE INITIATION AND PROGRESSION OF VASCULAR REMODELLING. EXPRESSION OF IMMUNOREGULATORY MOLECULES BY VASCULAR WALL COMPONENTS WITHIN THE ATHEROSCLEROTIC LESIONS IS ACCORDINGLY THOUGHT TO CONTRIBUTE TO THE ONGOING INFLAMMATORY PROCESS. BESIDES GENE REGULATORY PROTEINS (TRANSCRIPTION FACTORS), EPIGENETIC MECHANISMS ALSO PLAY AN ESSENTIAL AND FUNDAMENTAL ROLE IN THE TRANSCRIPTIONAL CONTROL OF GENE EXPRESSION. THESE EPIGENETIC MECHANISMS CHANGE THE ACCESSIBILITY OF CHROMATIN BY DNA METHYLATION AND HISTONE MODIFICATIONS. EPIGENETIC MODULATORS ARE THUS CRITICALLY INVOLVED IN THE REGULATION OF VASCULAR, IMMUNE AND TISSUE-SPECIFIC GENE EXPRESSION WITHIN THE ATHEROSCLEROTIC LESION. IMPORTANTLY, EPIGENETIC PROCESSES ARE REVERSIBLE AND MAY PROVIDE AN EXCELLENT THERAPEUTIC TARGET. THE CONCEPT OF EPIGENETIC REGULATION IS GRADUALLY BEING RECOGNIZED AS AN IMPORTANT FACTOR IN THE PATHOGENESIS OF ATHEROSCLEROSIS. RECENT RESEARCH PROVIDES AN ESSENTIAL LINK BETWEEN INFLAMMATION AND REPROGRAMMING OF THE EPIGENOME. IN THIS REVIEW WE THEREFORE DISCUSS THE BASIS OF EPIGENETIC REGULATION - AND THE CONTRIBUTION THEREOF IN THE REGULATION OF INFLAMMATORY PROCESSES IN GENERAL AND DURING ATHEROSCLEROSIS IN PARTICULAR. MOREOVER WE HIGHLIGHT POTENTIAL THERAPEUTIC INTERVENTIONS BASED ON EPIGENETIC MECHANISMS. 2010 15 6219 23 THE KEY ROLE OF DNA METHYLATION AND HISTONE ACETYLATION IN EPIGENETICS OF ATHEROSCLEROSIS. ATHEROSCLEROSIS, WHICH IS THE MOST COMMON CHRONIC DISEASE OF THE CORONARY ARTERY, CONSTITUTES A VASCULAR PATHOLOGY INDUCED BY INFLAMMATION AND PLAQUE ACCUMULATION WITHIN ARTERIAL VESSEL WALLS. BOTH DNA METHYLATION AND HISTONE MODIFICATIONS ARE EPIGENETIC CHANGES RELEVANT FOR ATHEROSCLEROSIS. RECENT STUDIES HAVE SHOWN THAT THE DNA METHYLATION AND HISTONE MODIFICATION SYSTEMS ARE CLOSELY INTERRELATED AND MECHANICALLY DEPENDENT ON EACH OTHER. HEREIN, WE EXPLORE THE FUNCTIONAL LINKAGE BETWEEN THESE SYSTEMS, WITH A PARTICULAR EMPHASIS ON SEVERAL RECENT FINDINGS SUGGESTING THAT HISTONE ACETYLATION CAN HELP IN TARGETING DNA METHYLATION AND THAT DNA METHYLATION MAY CONTROL GENE EXPRESSION DURING ATHEROSCLEROSIS. 2020 16 2168 26 EPIGENETIC MECHANISMS IN MONOCYTES/MACROPHAGES REGULATE INFLAMMATION IN CARDIOMETABOLIC AND VASCULAR DISEASE. CARDIOMETABOLIC AND VASCULAR DISEASE, WITH THEIR ASSOCIATED SECONDARY COMPLICATIONS, ARE THE LEADING CAUSE OF MORBIDITY AND MORTALITY IN WESTERN SOCIETY. CHRONIC INFLAMMATION IS A COMMON THEME THAT UNDERLIES INITIATION AND PROGRESSION OF CARDIOVASCULAR DISEASE. IN THIS REGARD, MONOCYTES/MACROPHAGES ARE KEY PLAYERS IN THE DEVELOPMENT OF A CHRONIC INFLAMMATORY STATE. OVER THE PAST DECADE, EPIGENETIC MODIFICATIONS, SUCH AS DNA METHYLATION AND POSTTRANSLATIONAL HISTONE PROCESSING, HAVE EMERGED AS IMPORTANT REGULATORS OF IMMUNE CELL PHENOTYPES. ACCUMULATING STUDIES REVEAL THE IMPORTANCE OF EPIGENETIC ENZYMES IN THE DYNAMIC REGULATION OF KEY SIGNALING PATHWAYS THAT ALTER MONOCYTE/MACROPHAGE PHENOTYPES IN RESPONSE TO ENVIRONMENTAL STIMULI. IN THIS REVIEW, WE HIGHLIGHT THE CURRENT PARADIGMS OF MONOCYTE/MACROPHAGE POLARIZATION AND THE EMERGING ROLE OF EPIGENETIC MODIFICATION IN THE REGULATION OF MONOCYTE/MACROPHAGE PHENOTYPE IN OBESITY, DIABETES MELLITUS, ATHEROSCLEROSIS, AND ABDOMINAL AORTIC ANEURYSMS. 2019 17 5710 26 SIRT1 DEFICIENCY IN MICROGLIA CONTRIBUTES TO COGNITIVE DECLINE IN AGING AND NEURODEGENERATION VIA EPIGENETIC REGULATION OF IL-1BETA. AGING IS THE PREDOMINANT RISK FACTOR FOR NEURODEGENERATIVE DISEASES. ONE KEY PHENOTYPE AS THE BRAIN AGES IS AN ABERRANT INNATE IMMUNE RESPONSE CHARACTERIZED BY PROINFLAMMATION. HOWEVER, THE MOLECULAR MECHANISMS UNDERLYING AGING-ASSOCIATED PROINFLAMMATION ARE POORLY DEFINED. WHETHER CHRONIC INFLAMMATION PLAYS A CAUSAL ROLE IN COGNITIVE DECLINE IN AGING AND NEURODEGENERATION HAS NOT BEEN ESTABLISHED. HERE WE REPORT A MECHANISTIC LINK BETWEEN CHRONIC INFLAMMATION AND AGING MICROGLIA AND A CAUSAL ROLE OF AGING MICROGLIA IN NEURODEGENERATIVE COGNITIVE DEFICITS. WE SHOWED THAT SIRT1 IS REDUCED WITH THE AGING OF MICROGLIA AND THAT MICROGLIAL SIRT1 DEFICIENCY HAS A CAUSATIVE ROLE IN AGING- OR TAU-MEDIATED MEMORY DEFICITS VIA IL-1BETA UPREGULATION IN MICE. INTERESTINGLY, THE SELECTIVE ACTIVATION OF IL-1BETA TRANSCRIPTION BY SIRT1 DEFICIENCY IS LIKELY MEDIATED THROUGH HYPOMETHYLATING THE SPECIFIC CPG SITES ON IL-1BETA PROXIMAL PROMOTER. IN HUMANS, HYPOMETHYLATION OF IL-1BETA IS STRONGLY ASSOCIATED WITH CHRONOLOGICAL AGE AND WITH ELEVATED IL-1BETA TRANSCRIPTION. OUR FINDINGS REVEAL A NOVEL EPIGENETIC MECHANISM IN AGING MICROGLIA THAT CONTRIBUTES TO COGNITIVE DEFICITS IN AGING AND NEURODEGENERATIVE DISEASES. 2015 18 6543 21 TRANSCRIPTOME REMODELING IN HYPOXIC INFLAMMATION. HYPOXIA IS AN INTEGRAL COMPONENT OF THE INFLAMED TISSUE MICROENVIRONMENT. TODAY, THE INFLUENCE OF HYPOXIA ON THE NATURAL EVOLUTION OF INFLAMMATORY RESPONSES IS WIDELY ACCEPTED; HOWEVER, MANY MOLECULAR AND CELLULAR MECHANISMS MEDIATING THIS RELATIONSHIP REMAIN TO BE CLARIFIED. HYPOXIC STRESS AFFECTS SEVERAL INDEPENDENT TRANSCRIPTIONAL REGULATORS RELATED TO INFLAMMATION IN WHICH HIF-1 AND NF-KAPPAB PLAY CENTRAL ROLES. TRANSCRIPTION FACTORS INTERACT WITH BOTH HATS AND HDACS, WHICH ARE COMPONENTS OF LARGE MULTIPROTEIN CO-REGULATORY COMPLEXES. THIS REVIEW SUMMARIZES THE CURRENT KNOWLEDGE ON HYPOXIA-RESPONSIVE TRANSCRIPTIONAL PATHWAYS IN INFLAMMATION AND THEIR IMPORTANCE IN THE ETIOLOGY OF CHRONIC INFLAMMATORY DISEASES, WITH THE PRIMARY FOCUS ON TRANSCRIPTIONAL CO-REGULATORS AND HISTONE MODIFICATIONS IN DEFINING GENE-SPECIFIC TRANSCRIPTIONAL RESPONSES IN HYPOXIA, AND ON THE RECENT PROGRESS IN THE UNDERSTANDING OF HYPOXIA-MEDIATED EPIGENETIC REPROGRAMMING. FURTHERMORE, THIS REVIEW DISCUSSES THE MOLECULAR CROSS-TALK BETWEEN GLUCOCORTICOID ANTI-INFLAMMATORY PATHWAYS AND HYPOXIA. 2010 19 1382 30 DIABETES ALTERS ACTIVATION AND REPRESSION OF PRO- AND ANTI-INFLAMMATORY SIGNALING PATHWAYS IN THE VASCULATURE. A CENTRAL MECHANISM DRIVING VASCULAR DISEASE IN DIABETES IS IMMUNE CELL-MEDIATED INFLAMMATION. IN DIABETES, ENHANCED OXIDATION AND GLYCATION OF MACROMOLECULES, SUCH AS LIPOPROTEINS, INSULTS THE ENDOTHELIUM, AND ACTIVATES BOTH INNATE AND ADAPTIVE ARMS OF THE IMMUNE SYSTEM BY GENERATING NEW ANTIGENS FOR PRESENTATION TO ADAPTIVE IMMUNE CELLS. CHRONIC INFLAMMATION OF THE ENDOTHELIUM IN DIABETES LEADS TO CONTINUOUS INFILTRATION AND ACCUMULATION OF LEUKOCYTES AT SITES OF ENDOTHELIAL CELL INJURY. WE WILL DESCRIBE THE CENTRAL ROLE OF THE MACROPHAGE AS A SOURCE OF SIGNALING MOLECULES AND DAMAGING BY-PRODUCTS WHICH ACTIVATE INFILTRATING LYMPHOCYTES IN THE TISSUE AND CONTRIBUTE TO THE PRO-OXIDANT AND PRO-INFLAMMATORY MICROENVIRONMENT. AN IMPORTANT ASPECT TO BE CONSIDERED IS THE DIABETES-ASSOCIATED DEFECTS IN THE IMMUNE SYSTEM, SUCH AS FEWER OR DYSFUNCTIONAL ATHERO-PROTECTIVE LEUKOCYTE SUBSETS IN THE DIABETIC LESION COMPARED TO NON-DIABETIC LESIONS. THIS REVIEW WILL DISCUSS THE KEY PRO-INFLAMMATORY SIGNALING PATHWAYS RESPONSIBLE FOR LEUKOCYTE RECRUITMENT AND ACTIVATION IN THE INJURED VESSEL, WITH PARTICULAR FOCUS ON PRO- AND ANTI-INFLAMMATORY PATHWAYS ABERRANTLY ACTIVATED OR REPRESSED IN DIABETES. WE AIM TO DESCRIBE THE INTERACTION BETWEEN ADVANCED GLYCATION END PRODUCTS AND THEIR PRINCIPLE RECEPTOR RAGE, ANGIOTENSIN II, AND THE ANG II TYPE 1 RECEPTOR, IN ADDITION TO REACTIVE OXYGEN SPECIES (ROS) PRODUCTION BY NADPH-OXIDASE ENZYMES THAT ARE RELEVANT TO VASCULAR AND IMMUNE CELL FUNCTION IN THE CONTEXT OF DIABETIC VASCULOPATHY. FURTHERMORE, WE WILL TOUCH ON RECENT ADVANCES IN EPIGENETIC MEDICINE THAT HAVE REVEALED HIGH GLUCOSE-MEDIATED CHANGES IN THE TRANSCRIPTION OF GENES WITH KNOWN PRO-INFLAMMATORY DOWNSTREAM TARGETS. FINALLY, NOVEL ANTI-ATHEROSCLEROSIS STRATEGIES THAT TARGET THE VASCULAR IMMUNE INTERFACE WILL BE EXPLORED; SUCH AS VACCINATION AGAINST MODIFIED LOW-DENSITY LIPOPROTEIN AND PHARMACOLOGICAL INHIBITION OF ROS-PRODUCING ENZYMES. 2013 20 4969 28 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