1 4395 119 MODM DNA METHYLTRANSFERASE METHYLOME ANALYSIS REVEALS A POTENTIAL ROLE FOR MORAXELLA CATARRHALIS PHASEVARIONS IN OTITIS MEDIA. MORAXELLA CATARRHALIS IS A SIGNIFICANT CAUSE OF OTITIS MEDIA AND EXACERBATIONS OF CHRONIC OBSTRUCTIVE PULMONARY DISEASE. HERE, WE CHARACTERIZE A PHASE-VARIABLE DNA METHYLTRANSFERASE (MODM), WHICH CONTAINS 5'-CAAC-3' REPEATS IN ITS OPEN READING FRAME THAT MEDIATE HIGH-FREQUENCY MUTATION RESULTING IN REVERSIBLE ON/OFF SWITCHING OF MODM EXPRESSION. THREE MODM ALLELES HAVE BEEN IDENTIFIED (MODM1-3), WITH MODM2 BEING THE MOST COMMONLY FOUND ALLELE. USING SINGLE-MOLECULE, REAL-TIME (SMRT) GENOME SEQUENCING AND METHYLOME ANALYSIS, WE HAVE DETERMINED THAT THE MODM2 METHYLATION TARGET IS 5'-GAR(M6)AC-3', AND 100% OF THESE SITES ARE METHYLATED IN THE GENOME OF THE M. CATARRHALIS 25239 MODM2 ON STRAIN. PROTEOMIC ANALYSIS OF MODM2 ON AND OFF VARIANTS REVEALED THAT MODM2 REGULATES EXPRESSION OF MULTIPLE GENES THAT HAVE POTENTIAL ROLES IN COLONIZATION, INFECTION, AND PROTECTION AGAINST HOST DEFENSES. INVESTIGATION OF THE DISTRIBUTION OF MODM ALLELES IN A PANEL OF M. CATARRHALIS STRAINS, ISOLATED FROM THE NASOPHARYNX OF HEALTHY CHILDREN OR MIDDLE EAR EFFUSIONS FROM PATIENTS WITH OTITIS MEDIA, REVEALED A STATISTICALLY SIGNIFICANT ASSOCIATION OF MODM3 WITH OTITIS MEDIA ISOLATES. THE MODULATION OF GENE EXPRESSION VIA THE MODM PHASE-VARIABLE REGULON (PHASEVARION), AND THE SIGNIFICANT ASSOCIATION OF THE MODM3 ALLELE WITH OTITIS MEDIA, SUGGESTS A KEY ROLE FOR MODM PHASEVARIONS IN THE PATHOGENESIS OF THIS ORGANISM. 2014 2 1124 29 COMPLETE GENOME SEQUENCE OF MORAXELLA CATARRHALIS STRAIN CCRI-195ME, ISOLATED FROM THE MIDDLE EAR. MORAXELLA CATARRHALIS IS AN IMPORTANT BACTERIAL PATHOGEN THAT CAUSES OTITIS MEDIA AND EXACERBATIONS OF CHRONIC OBSTRUCTIVE PULMONARY DISEASE. HERE, WE REPORT THE COMPLETE GENOME SEQUENCE OF M. CATARRHALIS STRAIN CCRI-195ME, WHICH CONTAINS THE PHASE-VARIABLE EPIGENETIC REGULATOR MODM3. 2017 3 6261 67 THE MORAXELLA CATARRHALIS PHASE-VARIABLE DNA METHYLTRANSFERASE MODM3 IS AN EPIGENETIC REGULATOR THAT AFFECTS BACTERIAL SURVIVAL IN AN IN VIVO MODEL OF OTITIS MEDIA. BACKGROUND: MORAXELLA CATARRHALIS IS A LEADING CAUSE OF OTITIS MEDIA (OM) AND CHRONIC OBSTRUCTIVE PULMONARY DISEASE (COPD). M. CATARRHALIS CONTAINS A TYPE III DNA ADENINE METHYLTRANSFERASE (MODM) THAT IS PHASE-VARIABLY EXPRESSED (I.E., ITS EXPRESSION IS SUBJECT TO RANDOM, REVERSIBLE ON/OFF SWITCHING). MODM HAS SIX TARGET RECOGNITION DOMAIN ALLELES (MODM1-6), AND WE HAVE PREVIOUSLY SHOWN THAT MODM2 IS THE PREDOMINANT ALLELE, WHILE MODM3 IS ASSOCIATED WITH OM. PHASE-VARIABLE DNA METHYLTRANSFERASES MEDIATE EPIGENETIC REGULATION AND MODULATE PATHOGENESIS IN SEVERAL BACTERIA. MODM2 OF M. CATARRHALIS REGULATES THE EXPRESSION OF A PHASEVARION CONTAINING GENES IMPORTANT FOR COLONIZATION AND INFECTION. HERE WE DESCRIBE THE PHASE-VARIABLE EXPRESSION OF MODM3, THE MODM3 METHYLATION SITE AND THE SUITE OF GENES REGULATED WITHIN THE MODM3 PHASEVARION. RESULTS: PHASE-VARIABLE EXPRESSION OF MODM3, MEDIATED BY VARIATION IN LENGTH OF A 5'-(CAAC)(N)-3' TETRANUCLEOTIDE REPEAT TRACT IN THE OPEN READING FRAME WAS DEMONSTRATED IN M. CATARRHALIS STRAIN CCRI-195ME WITH GENESCAN FRAGMENT LENGTH ANALYSIS AND WESTERN IMMUNOBLOT. WE DETERMINED THAT MODM3 IS AN ACTIVE N6-ADENINE METHYLTRANSFERASE THAT METHYLATES THE SEQUENCE 5'-AC(M6)ATC-3'. METHYLATION WAS DETECTED AT ALL 4446 5'-ACATC-3' SITES IN THE GENOME WHEN MODM3 IS EXPRESSED. RNASEQ ANALYSIS IDENTIFIED 31 GENES THAT ARE DIFFERENTIALLY EXPRESSED BETWEEN MODM3 ON AND OFF VARIANTS, INCLUDING FIVE GENES THAT ARE INVOLVED IN THE RESPONSE TO OXIDATIVE AND NITROSATIVE STRESS, WITH POTENTIAL ROLES IN BIOFILM FORMATION AND SURVIVAL IN ANAEROBIC ENVIRONMENTS. AN IN VIVO CHINCHILLA (CHINCHILLA LANIGERA) MODEL OF OTITIS MEDIA DEMONSTRATED THAT TRANSBULLAR CHALLENGE WITH THE MODM3 OFF VARIANT RESULTED IN AN INCREASED MIDDLE EAR BACTERIAL LOAD COMPARED TO A MODM3 ON VARIANT. IN ADDITION, CO-INFECTION EXPERIMENTS WITH NTHI AND M. CATARRHALIS MODM3 ON OR MODM3 OFF VARIANTS REVEALED THAT PHASE VARIATION OF MODM3 ALTERED SURVIVAL OF NTHI IN THE MIDDLE EAR DURING EARLY AND LATE STAGE INFECTION. CONCLUSIONS: PHASE VARIATION OF MODM3 EPIGENETICALLY REGULATES THE EXPRESSION OF A PHASEVARION CONTAINING MULTIPLE GENES THAT ARE POTENTIALLY IMPORTANT IN THE PROGRESSION OF OTITIS MEDIA. 2019 4 3064 32 GENOME-WIDE DNA METHYLATION ENCODES CARDIAC TRANSCRIPTIONAL REPROGRAMMING IN HUMAN ISCHEMIC HEART FAILURE. ISCHEMIC CARDIOMYOPATHY (ICM) IS THE CLINICAL ENDPOINT OF CORONARY HEART DISEASE AND A LEADING CAUSE OF HEART FAILURE. DESPITE GROWING DEMANDS TO DEVELOP PERSONALIZED APPROACHES TO TREAT ICM, PROGRESS IS LIMITED BY INADEQUATE KNOWLEDGE OF ITS PATHOGENESIS. SINCE EPIGENETICS HAS BEEN IMPLICATED IN THE DEVELOPMENT OF OTHER CHRONIC DISEASES, THE CURRENT STUDY WAS DESIGNED TO DETERMINE WHETHER TRANSCRIPTIONAL AND/OR EPIGENETIC CHANGES ARE SUFFICIENT TO DISTINGUISH ICM FROM OTHER ETIOLOGIES OF HEART FAILURE. SPECIFICALLY, WE HYPOTHESIZE THAT GENOME-WIDE DNA METHYLATION ENCODES TRANSCRIPTIONAL REPROGRAMMING IN ICM. RNA-SEQUENCING ANALYSIS WAS PERFORMED ON HUMAN ISCHEMIC LEFT VENTRICULAR TISSUE OBTAINED FROM PATIENTS WITH END-STAGE HEART FAILURE, WHICH ENRICHED KNOWN TARGETS OF THE POLYCOMB METHYLTRANSFERASE EZH2 COMPARED TO NON-ISCHEMIC HEARTS. COMBINED RNA SEQUENCING AND GENOME-WIDE DNA METHYLATION ANALYSIS REVEALED A ROBUST GENE EXPRESSION PATTERN CONSISTENT WITH SUPPRESSION OF OXIDATIVE METABOLISM, INDUCED ANAEROBIC GLYCOLYSIS, AND ALTERED CELLULAR REMODELING. LASTLY, KLF15 WAS IDENTIFIED AS A PUTATIVE UPSTREAM REGULATOR OF METABOLIC GENE EXPRESSION THAT WAS ITSELF REGULATED BY EZH2 IN A SET DOMAIN-DEPENDENT MANNER. OUR OBSERVATIONS THEREFORE DEFINE A NOVEL ROLE OF DNA METHYLATION IN THE METABOLIC REPROGRAMMING OF ICM. FURTHERMORE, WE IDENTIFY EZH2 AS AN EPIGENETIC REGULATOR OF KLF15 ALONG WITH DNA HYPERMETHYLATION, AND WE PROPOSE A NOVEL MECHANISM THROUGH WHICH CORONARY HEART DISEASE REPROGRAMS THE EXPRESSION OF BOTH INTERMEDIATE ENZYMES AND UPSTREAM REGULATORS OF CARDIAC METABOLISM SUCH AS KLF15. 2019 5 3204 27 HDAC3 REGULATES GINGIVAL FIBROBLAST INFLAMMATORY RESPONSES IN PERIODONTITIS. HISTONE DEACETYLASES (HDACS) ARE IMPORTANT REGULATORS OF GENE EXPRESSION THAT ARE ABERRANTLY REGULATED IN SEVERAL INFLAMMATORY AND INFECTIOUS DISEASES. HDAC INHIBITORS (HDACI) SUPPRESS INFLAMMATORY ACTIVATION OF VARIOUS CELL TYPES THROUGH EPIGENETIC AND NON-EPIGENETIC MECHANISMS, AND AMELIORATE PATHOLOGY IN A MOUSE MODEL OF PERIODONTITIS. ACTIVATION OF GINGIVAL FIBROBLASTS (GFS) SIGNIFICANTLY CONTRIBUTES TO THE DEVELOPMENT OF PERIODONTITIS AND THE ANAEROBIC BACTERIUM PORPHYROMONAS GINGIVALIS PLAYS A KEY ROLE IN DRIVING CHRONIC INFLAMMATION. HERE, WE ANALYZED THE ROLE OF HDACS IN INFLAMMATORY RESPONSES OF GFS. PAN-HDACI SUBEROYLANILIDE HYDROXAMIC ACID (SAHA) AND/OR ITF2357 (GIVINOSTAT) SIGNIFICANTLY REDUCED TNFALPHA- AND P. GINGIVALIS-INDUCIBLE EXPRESSION AND/OR PRODUCTION OF A CLUSTER OF INFLAMMATORY MEDIATORS IN HEALTHY DONOR GFS (IL1B, CCL2, CCL5, CXCL10, COX2, AND MMP3) WITHOUT AFFECTING CELL VIABILITY. SELECTIVE INHIBITION OF HDAC3/6, BUT NOT SPECIFIC HDAC1, HDAC6, OR HDAC8 INHIBITION, REPRODUCED THE SUPPRESSIVE EFFECTS OF PAN-HDACI ON THE INFLAMMATORY GENE EXPRESSION PROFILE INDUCED BY TNFALPHA AND P. GINGIVALIS, SUGGESTING A CRITICAL ROLE FOR HDAC3 IN GF INFLAMMATORY ACTIVATION. CONSISTENTLY, SILENCING OF HDAC3 EXPRESSION WITH SIRNA LARGELY RECAPITULATED THE EFFECTS OF HDAC3/6I ON MRNA LEVELS OF INFLAMMATORY MEDIATORS IN P. GINGIVALIS-INFECTED GFS. IN CONTRAST, P. GINGIVALIS INTERNALIZATION AND INTRACELLULAR SURVIVAL IN GFS REMAINED UNAFFECTED BY HDACI. ACTIVATION OF MITOGEN-ACTIVATED PROTEIN KINASES AND NFKAPPAB SIGNALING WAS UNAFFECTED BY GLOBAL OR HDAC3/6-SELECTIVE HDACI, AND NEW PROTEIN SYNTHESIS WAS NOT REQUIRED FOR GENE SUPPRESSION BY HDACI. FINALLY, PAN-HDACI AND HDAC3/6I SUPPRESSED P. GINGIVALIS-INDUCED EXPRESSION OF IL1B, CCL2, CCL5, CXCL10, MMP1, AND MMP3 IN GFS FROM PATIENTS WITH PERIODONTITIS. OUR RESULTS IDENTIFY HDAC3 AS AN IMPORTANT REGULATOR OF INFLAMMATORY GENE EXPRESSION IN GFS AND SUGGEST THAT THERAPEUTIC TARGETING OF HDAC ACTIVITY, IN PARTICULAR HDAC3, MAY BE CLINICALLY BENEFICIAL IN SUPPRESSING INFLAMMATION IN PERIODONTAL DISEASE. 2020 6 2273 43 EPIGENETIC REGULATION ALTERS BIOFILM ARCHITECTURE AND COMPOSITION IN MULTIPLE CLINICAL ISOLATES OF NONTYPEABLE HAEMOPHILUS INFLUENZAE. BIOFILMS PLAY A CRITICAL ROLE IN THE COLONIZATION, PERSISTENCE, AND PATHOGENESIS OF MANY HUMAN PATHOGENS. MULTIPLE MUCOSA-ASSOCIATED PATHOGENS HAVE EVOLVED A MECHANISM OF RAPID ADAPTATION, TERMED THE PHASEVARION, WHICH FACILITATES A COORDINATED REGULATION OF NUMEROUS GENES THROUGHOUT THE BACTERIAL GENOME. THIS EPIGENETIC REGULATION OCCURS VIA PHASE VARIATION OF A DNA METHYLTRANSFERASE, MOD. THE PHASEVARION OF NONTYPEABLE HAEMOPHILUS INFLUENZAE (NTHI) SIGNIFICANTLY AFFECTS THE SEVERITY OF EXPERIMENTAL OTITIS MEDIA AND REGULATES SEVERAL DISEASE-RELATED PROCESSES. HOWEVER, THE ROLE OF THE NTHI PHASEVARION IN BIOFILM FORMATION IS UNCLEAR. THE PRESENT STUDY SHOWS THAT THE PHASEVARIONS OF MULTIPLE NTHI CLINICAL ISOLATES REGULATE IN VITRO BIOFILM FORMATION UNDER DISEASE-SPECIFIC MICROENVIRONMENTAL CONDITIONS. THE IMPACT OF PHASEVARION REGULATION WAS GREATEST UNDER ALKALINE CONDITIONS THAT MIMIC THOSE KNOWN TO OCCUR IN THE MIDDLE EAR DURING DISEASE. UNDER ALKALINE CONDITIONS, NTHI STRAINS THAT EXPRESS THE MODA2 METHYLTRANSFERASE FORMED BIOFILMS WITH SIGNIFICANTLY GREATER BIOMASS AND LESS DISTINCT ARCHITECTURE THAN THOSE FORMED BY A MODA2-DEFICIENT POPULATION. THE BIOFILMS FORMED BY NTHI STRAINS THAT EXPRESS MODA2 ALSO CONTAINED LESS EXTRACELLULAR DNA (EDNA) AND SIGNIFICANTLY LESS EXTRACELLULAR HU, A DNABII DNA-BINDING PROTEIN CRITICAL FOR BIOFILM STRUCTURAL STABILITY. STABLE BIOFILM STRUCTURE IS CRITICAL FOR BACTERIAL PATHOGENESIS AND PERSISTENCE IN MULTIPLE EXPERIMENTAL MODELS OF DISEASE. THESE RESULTS IDENTIFY A ROLE FOR THE PHASEVARION IN REGULATION OF BIOFILM FORMATION, A PROCESS INTEGRAL TO THE CHRONIC NATURE OF MANY INFECTIONS. UNDERSTANDING THE ROLE OF THE PHASEVARION IN BIOFILM FORMATION IS CRITICAL TO THE DEVELOPMENT OF PREVENTION AND TREATMENT STRATEGIES FOR THESE CHRONIC DISEASES.IMPORTANCE UPPER RESPIRATORY TRACT INFECTIONS ARE THE NUMBER ONE REASON FOR A CHILD TO VISIT THE EMERGENCY DEPARTMENT, AND OTITIS MEDIA (MIDDLE EAR INFECTION) RANKS THIRD OVERALL. BIOFILMS CONTRIBUTE SIGNIFICANTLY TO THE CHRONIC NATURE OF BACTERIAL RESPIRATORY TRACT INFECTIONS, INCLUDING OTITIS MEDIA, AND MAKE THESE DISEASES PARTICULARLY DIFFICULT TO TREAT. SEVERAL MUCOSA-ASSOCIATED HUMAN PATHOGENS UTILIZE A MECHANISM OF RAPID ADAPTATION TERMED THE PHASEVARION, OR PHASEVARIABLE REGULON, TO RESIST ENVIRONMENTAL AND HOST IMMUNE PRESSURES. IN THIS STUDY, WE ASSESSED THE ROLE OF THE PHASEVARION IN REGULATION OF BIOFILM FORMATION BY NONTYPEABLE HAEMOPHILUS INFLUENZAE (NTHI), WHICH CAUSES NUMEROUS RESPIRATORY TRACT DISEASES. WE FOUND THAT THE NTHI PHASEVARION REGULATES BIOFILM STRUCTURE AND CRITICAL BIOFILM MATRIX COMPONENTS UNDER DISEASE-SPECIFIC CONDITIONS. THE FINDINGS OF THIS WORK COULD BE SIGNIFICANT IN THE DESIGN OF IMPROVED STRATEGIES AGAINST NTHI INFECTIONS, AS WELL AS DISEASES DUE TO OTHER PATHOGENS THAT UTILIZE A PHASEVARION. 2018 7 4493 28 MORAXELLA CATARRHALIS INDUCES INFLAMMATORY RESPONSE OF BRONCHIAL EPITHELIAL CELLS VIA MAPK AND NF-KAPPAB ACTIVATION AND HISTONE DEACETYLASE ACTIVITY REDUCTION. MORAXELLA CATARRHALIS IS A MAJOR CAUSE OF INFECTIOUS EXACERBATIONS OF CHRONIC OBSTRUCTIVE LUNG DISEASE (COPD) AND MAY ALSO CONTRIBUTE TO THE PATHOGENESIS OF COPD. LITTLE IS KNOWN ABOUT M. CATARRHALIS-BRONCHIAL EPITHELIUM INTERACTION. WE INVESTIGATED ACTIVATION OF M. CATARRHALIS INFECTED BRONCHIAL EPITHELIAL CELLS AND CHARACTERIZED THE SIGNAL TRANSDUCTION PATHWAYS. MOREOVER, WE TESTED THE HYPOTHESIS THAT THE M. CATARRHALIS-INDUCED CYTOKINE EXPRESSION IS REGULATED BY ACETYLATION OF HISTONE RESIDUES AND CONTROLLED BY HISTONE DEACETYLASE ACTIVITY (HDAC). WE DEMONSTRATED THAT M. CATARRHALIS INDUCED A STRONG TIME- AND DOSE-DEPENDENT INFLAMMATORY RESPONSE IN THE BRONCHIAL EPITHELIAL CELL LINE (BEAS-2B), CHARACTERIZED BY THE RELEASE OF IL-8 AND GM-CSF. FOR THIS CYTOKINE LIBERATION ACTIVATION OF THE ERK AND P38 MITOGEN-ACTIVATED PROTEIN (MAP) KINASES AND TRANSCRIPTION FACTOR NF-KAPPAB WAS REQUIRED. FURTHERMORE, M. CATARRHALIS-INFECTED BRONCHIAL EPITHELIAL CELLS SHOWED AN ENHANCED ACETYLATION OF HISTONE H3 AND H4 GLOBALLY AND AT THE PROMOTER OF THE IL8 GENE. PREVENTING HISTONE DEACETYLATION BY THE HISTONE DEACETYLASE INHIBITOR TRICHOSTATIN A AUGMENTED THE M. CATARRHALIS-INDUCED IL-8 RESPONSE. AFTER EXPOSURE TO M. CATARRHALIS, WE FOUND A DECREASE IN GLOBAL HISTONE DEACETYLASE EXPRESSION AND ACTIVITY. OUR FINDINGS SUGGEST THAT M. CATARRHALIS-INDUCED ACTIVATION OF IL8 GENE TRANSCRIPTION WAS CAUSED BY INTERFERENCE WITH EPIGENETIC MECHANISMS REGULATING IL8 GENE ACCESSIBILITY. OUR FINDINGS PROVIDE INSIGHT INTO IMPORTANT MOLECULAR AND CELLULAR MECHANISMS OF M. CATARRHALIS-INDUCED ACTIVATION OF HUMAN BRONCHIAL EPITHELIUM. 2006 8 3585 30 IMPACT OF THE EXPOSOME ON THE EPIGENOME IN INFLAMMATORY BOWEL DISEASE PATIENTS AND ANIMAL MODELS. INFLAMMATORY BOWEL DISEASES (IBD) ARE CHRONIC INFLAMMATORY DISORDERS OF THE GASTROINTESTINAL TRACT THAT ENCOMPASS TWO MAIN PHENOTYPES, NAMELY CROHN'S DISEASE AND ULCERATIVE COLITIS. THESE CONDITIONS OCCUR IN GENETICALLY PREDISPOSED INDIVIDUALS IN RESPONSE TO ENVIRONMENTAL FACTORS. EPIGENETICS, ACTING BY DNA METHYLATION, POST-TRANSLATIONAL HISTONES MODIFICATIONS OR BY NON-CODING RNAS, COULD EXPLAIN HOW THE EXPOSOME (OR ALL ENVIRONMENTAL INFLUENCES OVER THE LIFE COURSE, FROM CONCEPTION TO DEATH) COULD INFLUENCE THE GENE EXPRESSION TO CONTRIBUTE TO INTESTINAL INFLAMMATION. WE PERFORMED A SCOPING SEARCH USING MEDLINE TO IDENTIFY ALL THE ELEMENTS OF THE EXPOSOME THAT MAY PLAY A ROLE IN INTESTINAL INFLAMMATION THROUGH EPIGENETIC MODIFICATIONS, AS WELL AS THE UNDERLYING MECHANISMS. THE ENVIRONMENTAL FACTORS EPIGENETICALLY INFLUENCING THE OCCURRENCE OF INTESTINAL INFLAMMATION ARE THE MATERNAL LIFESTYLE (MAINLY DIET, THE OCCURRENCE OF INFECTION DURING PREGNANCY AND SMOKING); BREASTFEEDING; MICROBIOTA; DIET (INCLUDING A LOW-FIBER DIET, HIGH-FAT DIET AND DEFICIENCY IN MICRONUTRIENTS); SMOKING HABITS, VITAMIN D AND DRUGS (E.G., IBD TREATMENTS, ANTIBIOTICS AND PROBIOTICS). INFLUENCED BY BOTH MICROBIOTA AND DIET, SHORT-CHAIN FATTY ACIDS ARE GUT MICROBIOTA-DERIVED METABOLITES RESULTING FROM THE ANAEROBIC FERMENTATION OF NON-DIGESTIBLE DIETARY FIBERS, PLAYING AN EPIGENETICALLY MEDIATED ROLE IN THE INTEGRITY OF THE EPITHELIAL BARRIER AND IN THE DEFENSE AGAINST INVADING MICROORGANISMS. ALTHOUGH THE IMPACT OF SOME ENVIRONMENTAL FACTORS HAS BEEN IDENTIFIED, THE EXPOSOME-INDUCED EPIMUTATIONS IN IBD REMAIN A LARGELY UNDEREXPLORED FIELD. HOW THESE ENVIRONMENTAL EXPOSURES INDUCE EPIGENETIC MODIFICATIONS (IN TERMS OF DURATION, FREQUENCY AND THE TIMING AT WHICH THEY OCCUR) AND HOW OTHER ENVIRONMENTAL FACTORS ASSOCIATED WITH IBD MODULATE EPIGENETICS DESERVE TO BE FURTHER INVESTIGATED. 2022 9 4563 31 MYELOID DNA METHYLTRANSFERASE3B DEFICIENCY AGGRAVATES PULMONARY FIBROSIS BY ENHANCING PROFIBROTIC MACROPHAGE ACTIVATION. BACKGROUND: IDIOPATHIC PULMONARY FIBROSIS (IPF) IS A CHRONIC, PROGRESSIVE AND SEVERE DISEASE CHARACTERIZED BY EXCESSIVE MATRIX DEPOSITION IN THE LUNGS. MACROPHAGES PLAY CRUCIAL ROLES IN MAINTAINING LUNG HOMEOSTASIS BUT ARE ALSO CENTRAL IN THE PATHOGENESIS OF LUNG DISEASES LIKE PULMONARY FIBROSIS. ESPECIALLY, MACROPHAGE POLARIZATION/ACTIVATION SEEMS TO PLAY A CRUCIAL ROLE IN PATHOLOGY AND EPIGENETIC REPROGRAMING IS WELL-KNOWN TO REGULATE MACROPHAGE POLARIZATION. DNA METHYLATION ALTERATIONS IN IPF LUNGS HAVE BEEN WELL DOCUMENTED, BUT THE ROLE OF DNA METHYLATION IN SPECIFIC CELL TYPES, ESPECIALLY MACROPHAGES, IS POORLY DEFINED. METHODS: IN ORDER TO DETERMINE THE ROLE OF DNA METHYLATION IN MACROPHAGES DURING PULMONARY FIBROSIS, WE SUBJECTED MACROPHAGE SPECIFIC DNA METHYLTRANSFERASE (DNMT)3B, WHICH MEDIATES THE DE NOVO DNA METHYLATION, DEFICIENT MICE TO THE BLEOMYCIN-INDUCED PULMONARY FIBROSIS MODEL. MACROPHAGE POLARIZATION AND FIBROTIC PARAMETERS WERE EVALUATED AT 21 DAYS AFTER BLEOMYCIN ADMINISTRATION. DNMT3B KNOCKOUT AND WILD TYPE BONE MARROW-DERIVED MACROPHAGES WERE STIMULATED WITH EITHER INTERLEUKIN (IL)4 OR TRANSFORMING GROWTH FACTOR BETA 1 (TGFB1) IN VITRO, AFTER WHICH PROFIBROTIC GENE EXPRESSION AND DNA METHYLATION AT THE ARG1 PROMOTOR WERE DETERMINED. RESULTS: WE SHOW THAT DNMT3B DEFICIENCY PROMOTES ALTERNATIVE MACROPHAGE POLARIZATION INDUCED BY IL4 AND TGFB1 IN VITRO AND ALSO ENHANCES PROFIBROTIC MACROPHAGE POLARIZATION IN THE ALVEOLAR SPACE DURING PULMONARY FIBROSIS IN VIVO. MOREOVER, MYELOID SPECIFIC DELETION OF DNMT3B PROMOTED THE DEVELOPMENT OF EXPERIMENTAL PULMONARY FIBROSIS. CONCLUSIONS: IN SUMMARY, THESE DATA SUGGEST THAT MYELOID DNMT3B REPRESSES FIBROTIC MACROPHAGE POLARIZATION AND PROTECTS AGAINST BLEOMYCIN INDUCED PULMONARY FIBROSIS. 2022 10 3767 24 INTEGRATIVE EPIGENOMIC ANALYSIS IN DIFFERENTIATED HUMAN PRIMARY BRONCHIAL EPITHELIAL CELLS EXPOSED TO CIGARETTE SMOKE. CIGARETTE SMOKE (CS) IS ONE OF THE MAJOR RISK FACTORS FOR MANY PULMONARY DISEASES, INCLUDING CHRONIC OBSTRUCTIVE PULMONARY DISEASE (COPD) AND LUNG CANCER. THE FIRST LINE OF DEFENSE FOR CS EXPOSURE IS THE BRONCHIAL EPITHELIAL CELLS. ELUCIDATION OF THE EPIGENETIC CHANGES DURING CS EXPOSURE IS KEY TO GAINING A MECHANISTIC UNDERSTANDING INTO HOW MATURE AND DIFFERENTIATED BRONCHIAL EPITHELIAL CELLS RESPOND TO CS. THEREFORE, WE PERFORMED EPIGENOMIC PROFILING IN CONJUNCTION WITH TRANSCRIPTIONAL PROFILING IN WELL-DIFFERENTIATED HUMAN BRONCHIAL EPITHELIAL (HBE) CELLS CULTURED IN AIR-LIQUID INTERFACE (ALI) EXPOSED TO THE VAPOR PHASE OF CS. THE GENOME-WIDE ENRICHMENT OF HISTONE 3 LYSINE 27 ACETYLATION WAS DETECTED BY CHROMATIN IMMUNOPRECIPITATION FOLLOWED BY NEXT GENERATION SEQUENCING (CHIP-SEQ) IN HBE CELLS AND SUGGESTED THE PLAUSIBLE BINDING OF SPECIFIC TRANSCRIPTION FACTORS RELATED TO CS EXPOSURE. ADDITIONALLY, INTERROGATION OF CHIP-SEQ DATA WITH GENE EXPRESSION PROFILING OF HBE CELLS AFTER CS EXPOSURE FOR DIFFERENT DURATIONS (3 HOURS, 2 DAYS, 4 DAYS) SUGGESTED THAT EARLIER EPIGENETIC CHANGES (3 HOURS AFTER CS EXPOSURE) MAY BE ASSOCIATED WITH LATER GENE EXPRESSION CHANGES INDUCED BY CS EXPOSURE (4 DAYS). THE INTEGRATION OF EPIGENETICS AND GENE EXPRESSION DATA REVEALED SIGNALING PATHWAYS RELATED TO CS-INDUCED EPIGENETIC CHANGES IN HBE CELLS THAT MAY IDENTIFY NOVEL REGULATORY PATHWAYS RELATED TO CS-INDUCED COPD. 2018 11 589 27 BET BROMODOMAIN INHIBITORS SUPPRESS INFLAMMATORY ACTIVATION OF GINGIVAL FIBROBLASTS AND EPITHELIAL CELLS FROM PERIODONTITIS PATIENTS. BET BROMODOMAIN PROTEINS ARE IMPORTANT EPIGENETIC REGULATORS OF GENE EXPRESSION THAT BIND ACETYLATED HISTONE TAILS AND REGULATE THE FORMATION OF ACETYLATION-DEPENDENT CHROMATIN COMPLEXES. BET INHIBITORS SUPPRESS INFLAMMATORY RESPONSES IN MULTIPLE CELL TYPES AND ANIMAL MODELS, AND PROTECT AGAINST BONE LOSS IN EXPERIMENTAL PERIODONTITIS IN MICE. HERE, WE ANALYZED THE ROLE OF BET PROTEINS IN INFLAMMATORY ACTIVATION OF GINGIVAL FIBROBLASTS (GFS) AND GINGIVAL EPITHELIAL CELLS (GECS). WE SHOW THAT THE BET INHIBITORS I-BET151 AND JQ1 SIGNIFICANTLY REDUCED EXPRESSION AND/OR PRODUCTION OF DISTINCT, BUT OVERLAPPING, PROFILES OF CYTOKINE-INDUCIBLE MEDIATORS OF INFLAMMATION AND BONE RESORPTION IN GFS FROM HEALTHY DONORS (IL6, IL8, IL1B, CCL2, CCL5, COX2, AND MMP3) AND THE GEC LINE TIGK (IL6, IL8, IL1B, CXCL10, MMP9) WITHOUT AFFECTING CELL VIABILITY. ACTIVATION OF MITOGEN-ACTIVATED PROTEIN KINASE AND NUCLEAR FACTOR-KAPPAB PATHWAYS WAS UNAFFECTED BY I-BET151, AS WAS THE HISTONE ACETYLATION STATUS, AND NEW PROTEIN SYNTHESIS WAS NOT REQUIRED FOR THE ANTI-INFLAMMATORY EFFECTS OF BET INHIBITION. I-BET151 AND JQ1 ALSO SUPPRESSED EXPRESSION OF INFLAMMATORY CYTOKINES, CHEMOKINES, AND OSTEOCLASTOGENIC MEDIATORS IN GFS AND TIGKS INFECTED WITH THE KEY PERIODONTAL PATHOGEN PORPHYROMONAS GINGIVALIS. NOTABLY, P. GINGIVALIS INTERNALIZATION AND INTRACELLULAR SURVIVAL IN GFS AND TIGKS REMAINED UNAFFECTED BY BET INHIBITORS. FINALLY, INHIBITION OF BET PROTEINS SIGNIFICANTLY REDUCED P. GINGIVALIS-INDUCED INFLAMMATORY MEDIATOR EXPRESSION IN GECS AND GFS FROM PATIENTS WITH PERIODONTITIS. OUR RESULTS DEMONSTRATE THAT BET INHIBITORS MAY BLOCK THE EXCESSIVE INFLAMMATORY MEDIATOR PRODUCTION BY RESIDENT CELLS OF THE GINGIVAL TISSUE AND IDENTIFY THE BET FAMILY OF EPIGENETIC READER PROTEINS AS A POTENTIAL THERAPEUTIC TARGET IN THE TREATMENT OF PERIODONTAL DISEASE. 2019 12 4980 20 PATHOPHYSIOLOGY OF LIVER FIBROSIS. PROGRESSIVE ACCUMULATION OF FIBRILLAR EXTRACELLULAR MATRIX (ECM) IN THE LIVER IS THE CONSEQUENCE OF REITERATED LIVER TISSUE DAMAGE DUE TO INFECTIVE (MOSTLY HEPATITIS B AND C VIRUSES), TOXIC/DRUG-INDUCED, METABOLIC AND AUTOIMMUNE CAUSES, AND THE RELATIVE CHRONIC ACTIVATION OF THE WOUND-HEALING REACTION. THE PROCESS MAY RESULT IN CLINICALLY EVIDENT LIVER CIRRHOSIS AND HEPATIC FAILURE. ALTHOUGH CIRRHOSIS IS THE COMMON RESULT OF PROGRESSIVE FIBROGENESIS, THERE ARE DISTINCT PATTERNS OF FIBROTIC DEVELOPMENT RELATED TO THE UNDERLYING DISORDERS CAUSING THE FIBROSIS. THESE DIFFERENT PATTERNS OF FIBROGENIC EVOLUTION ARE RELATED TO DIFFERENT FACTORS AND PARTICULARLY: (1) THE TOPOGRAPHIC LOCALIZATION OF TISSUE DAMAGE, (2) THE RELATIVE CONCENTRATION OF PROFIBROGENIC FACTORS AND (3) THE PREVALENT PROFIBROGENIC MECHANISM(S). THE MECHANISMS RESPONSIBLE FOR THE FIBROGENIC EVOLUTION OF CHRONIC LIVER DISEASES CAN BE SUMMARIZED IN THREE MAIN GROUPS: CHRONIC ACTIVATION OF THE WOUND-HEALING REACTION, OXIDATIVE STRESS-RELATED MOLECULAR MECHANISMS, AND THE DERANGEMENT OF THE SO-CALLED 'EPITHELIAL-MESENCHYMAL' INTERACTION LEADING TO THE GENERATION OF REACTIVE CHOLANGIOCYTES AND PERIBILIARY FIBROSIS. MOST OF THE KNOWLEDGE ON THE CELL AND MOLECULAR BIOLOGY OF HEPATIC FIBROSIS DERIVES FROM IN VITRO STUDIES EMPLOYING CULTURE OF ACTIVATED HEPATIC STELLATE CELLS ISOLATED FROM RAT, MOUSE OR HUMAN LIVER. IT IS NOW EVIDENT THAT OTHER ECM-PRODUCING CELLS, I.E. FIBROBLASTS AND MYOFIBROBLASTS OF THE PORTAL TRACT AND CIRCULATING 'FIBROCYTES', ARE LIKELY TO CONTRIBUTE TO LIVER FIBROSIS. MORE RECENTLY, THE ATTENTION IS PROGRESSIVELY SHIFTING TO THE PROFIBROTIC MICROENVIRONMENT OF THE LIVER WITH INCREASING INTEREST FOR THE ROLE OF IMMUNE CELLS AND SPECIFIC SUBSETS OF MACROPHAGES REGULATING THE PROGRESSION OR THE REGRESSION OF FIBROSIS, THE ROLE OF INTESTINAL MICROBIOTA AND THE INFLUENCE OF TISSUE STIFFNESS. OTHER MAJOR AREAS OF DEVELOPMENT INCLUDE THE ROLE OF TISSUE HYPOXIA AND THE ESTABLISHMENT OF AN ANAEROBIC PROINFLAMMATORY ENVIRONMENT AND THE INFLUENCE OF EPIGENETIC MODIFICATION IN CONDITIONING THE PROGRESSION OF FIBROSIS. 2015 13 4303 24 MICRORNA-223 INHIBITS TISSUE FACTOR EXPRESSION IN VASCULAR ENDOTHELIAL CELLS. OBJECTIVE: ATHEROSCLEROSIS IS A CHRONIC INFLAMMATORY PROCESS, IN WHICH VASCULAR ENDOTHELIAL CELLS (ECS) BECOME DYSFUNCTIONAL OWING TO THE EFFECTS OF CHEMICAL SUBSTANCES, SUCH AS INFLAMMATORY FACTOR AND GROWTH FACTORS. TISSUE FACTOR (TF) EXPRESSION IS INDUCED BY THE ABOVE CHEMICAL SUBSTANCES IN ACTIVATED ECS. TF INITIATES THROMBOSIS ON DISRUPTED ATHEROSCLEROTIC PLAQUES WHICH PLAYS AN ESSENTIAL ROLE DURING THE ONSET OF ACUTE CORONARY SYNDROMES (ACS). INCREASING EVIDENCES SUGGEST THE IMPORTANT ROLE OF MICRORNAS AS EPIGENETIC REGULATORS OF ATHEROSCLEROTIC DISEASE. THE AIM OF OUR STUDY IS TO IDENTIFY IF MICRORNA-223 (MIR-223) TARGETS TF IN ECS. METHODS AND RESULTS: BIOINFORMATIC ANALYSIS SHOWED THAT TF IS A TARGET CANDIDATE OF MIR-223. WESTERN BLOTTING ANALYSIS REVEALED THAT TUMOR NECROSIS FACTOR ALPHA (TNF-ALPHA) INCREASED TF EXPRESSION IN AORTA OF C57BL/6J MICE AND CULTURED ECS (EA.HY926 CELLS AND HUVEC) AFTER 4 H TREATMENT. IN TNF-ALPHA TREATED ECS, TF MRNA WAS ALSO INCREASED MEASURED BY REAL-TIME PCR. REAL-TIME PCR RESULTS SHOWED THAT MIR-223 LEVELS WERE DOWNREGULATED IN TNF-ALPHA-TREATED AORTA OF C57BL/6J MICE AND CULTURED ECS. TRANSFECTION OF ECS WITH MIR-223 MIMIC OR MIR-223 INHIBITOR MODIFIED TF EXPRESSION BOTH IN MRNA AND PROTEIN LEVELS. LUCIFERASE ASSAYS CONFIRMED THAT MIR-223 SUPPRESSED TF EXPRESSION BY BINDING TO THE SEQUENCE OF TF 3'-UNTRANSLATED REGIONS (3'UTR). TF PROCOAGULANT ACTIVITY WAS INHIBITED BY OVEREXPRESSING MIR-223 WITH OR WITHOUT TNF-ALPHA STIMULATION. CONCLUSIONS: MIR-223-MEDIATED SUPPRESSION OF TF EXPRESSION PROVIDES A NOVEL MOLECULAR MECHANISM FOR THE REGULATION OF COAGULATION CASCADE, AND SUGGESTS A CLUE AGAINST THROMBOGENESIS DURING THE PROCESS OF ATHEROSCLEROTIC PLAQUE RUPTURE. 2014 14 172 24 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 15 3512 22 IDIOPATHIC PULMONARY FIBROSIS. IDIOPATHIC PULMONARY FIBROSIS IS A DEVASTATING, AGE-RELATED LUNG DISEASE OF UNKNOWN CAUSE THAT HAS FEW TREATMENT OPTIONS. THIS DISEASE WAS ONCE THOUGHT TO BE A CHRONIC INFLAMMATORY PROCESS, BUT CURRENT EVIDENCE INDICATES THAT THE FIBROTIC RESPONSE IS DRIVEN BY ABNORMALLY ACTIVATED ALVEOLAR EPITHELIAL CELLS (AECS). THESE CELLS PRODUCE MEDIATORS THAT INDUCE THE FORMATION OF FIBROBLAST AND MYOFIBROBLAST FOCI THROUGH THE PROLIFERATION OF RESIDENT MESENCHYMAL CELLS, ATTRACTION OF CIRCULATING FIBROCYTES, AND STIMULATION OF THE EPITHELIAL TO MESENCHYMAL TRANSITION. THE FIBROBLAST AND MYOFIBROBLAST FOCI SECRETE EXCESSIVE AMOUNTS OF EXTRACELLULAR MATRIX, MAINLY COLLAGENS, RESULTING IN SCARRING AND DESTRUCTION OF THE LUNG ARCHITECTURE. THE MECHANISMS THAT LINK IDIOPATHIC PULMONARY FIBROSIS WITH AGEING AND ABERRANT EPITHELIAL ACTIVATION ARE UNKNOWN; EVIDENCE SUGGESTS THAT THE ABNORMAL RECAPITULATION OF DEVELOPMENTAL PATHWAYS AND EPIGENETIC CHANGES HAVE A ROLE. IN THIS SEMINAR, WE REVIEW RECENT DATA ON THE CLINICAL COURSE, THERAPEUTIC OPTIONS, AND UNDERLYING MECHANISMS THOUGHT TO BE INVOLVED IN THE PATHOGENESIS OF IDIOPATHIC PULMONARY FIBROSIS. 2011 16 6111 15 THE EPIGENETIC ARCHITECTURE AT GENE PROMOTERS DETERMINES CELL TYPE-SPECIFIC LPS TOLERANCE. SYNOVIAL FIBROBLASTS (SF) DRIVE INFLAMMATION AND JOINT DESTRUCTION IN CHRONIC ARTHRITIS. HERE WE SHOW THAT SF POSSESS A DISTINCT TYPE OF LPS TOLERANCE COMPARED TO MACROPHAGES AND OTHER TYPES OF FIBROBLASTS. IN SF AND DERMAL FIBROBLASTS, GENES THAT WERE NON-TOLERIZABLE AFTER REPEATED LPS STIMULATION INCLUDED PRO-INFLAMMATORY CYTOKINES, CHEMOKINES AND MATRIX METALLOPROTEINASES, WHEREAS ANTI-VIRAL GENES WERE TOLERIZABLE. IN MACROPHAGES, ALL MEASURED GENES WERE TOLERIZABLE, WHEREAS IN GINGIVAL AND FORESKIN FIBROBLASTS THESE GENES WERE NON-TOLERIZABLE. REPEATED STIMULATION OF SF WITH LPS RESULTED IN LOSS OF ACTIVATING HISTONE MARKS ONLY IN PROMOTERS OF TOLERIZABLE GENES. THE EPIGENETIC LANDSCAPE AT PROMOTERS OF TOLERIZABLE GENES WAS SIMILAR IN UNSTIMULATED SF AND MONOCYTES, WHEREAS THE BASAL CONFIGURATION OF HISTONE MARKS PROFOUNDLY DIFFERED IN GENES THAT WERE NON-TOLERIZABLE IN SF ONLY. OUR DATA SUGGEST THAT THE EPIGENETIC CONFIGURATION AT GENE PROMOTERS REGULATES CELL-SPECIFIC LPS-INDUCED RESPONSES AND PRIMES SF TO SUSTAIN THEIR INFLAMMATORY RESPONSE IN CHRONIC ARTHRITIS. 2017 17 5592 25 ROLE OF TUMOR NECROSIS FACTOR-ALPHA IN THE HUMAN SYSTEMIC ENDOTOXIN-INDUCED TRANSCRIPTOME. TNFALPHA HAS BEEN IMPLICATED IN THE PATHOGENESIS OF VARIOUS INFLAMMATORY DISEASES. DIFFERENT STRATEGIES TO INHIBIT TNFALPHA IN PATIENTS WITH SEPSIS AND CHRONIC INFLAMMATORY CONDITIONS HAVE SHOWN CONTRASTING OUTCOMES. ALTHOUGH TNFALPHA INHIBITORS ARE WIDELY USED IN CLINICAL PRACTICE, THE IMPACT OF TNFALPHA ANTAGONISM ON WHITE BLOOD CELL GENE EXPRESSION PROFILES DURING ACUTE INFLAMMATION IN HUMANS IN VIVO HAS NOT BEEN ASSESSED. WE HERE LEVERAGED THE ESTABLISHED MODEL OF HUMAN ENDOTOXEMIA TO EXAMINE THE EFFECT OF THE TNFALPHA ANTAGONIST, ETANERCEPT, ON THE GENOME-WIDE TRANSCRIPTIONAL RESPONSES IN CIRCULATING LEUKOCYTES INDUCED BY INTRAVENOUS LPS ADMINISTRATION IN MALE SUBJECTS. ETANERCEPT PRE-TREATMENT RESULTED IN A MARKEDLY DAMPENED TRANSCRIPTIONAL RESPONSE TO LPS. GENE CO-EXPRESSION NETWORK ANALYSIS REVEALED THIS LPS-INDUCED TRANSCRIPTOME CAN BE CATEGORIZED AS TNFALPHA RESPONSIVE AND NON-RESPONSIVE MODULES. HIGHLY SIGNIFICANT TNFALPHA RESPONSIVE MODULES INCLUDE NF-KB SIGNALING, ANTIVIRAL RESPONSES AND T-CELL MEDIATED RESPONSES. WITHIN THESE TNFALPHA RESPONSIVE MODULES WE DELINEATE FUNDAMENTAL GENES INVOLVED IN EPIGENETIC MODIFICATIONS, TRANSCRIPTIONAL INITIATION AND ELONGATION. THUS, WE PROVIDE COMPREHENSIVE INFORMATION ABOUT MOLECULAR PATHWAYS THAT MIGHT BE TARGETED BY THERAPEUTIC INTERVENTIONS THAT SEEK TO INHIBIT TNFALPHA ACTIVITY DURING HUMAN INFLAMMATORY DISEASES. 2013 18 5915 25 TARGETING A PHOSPHO-STAT3-MIRNAS PATHWAY IMPROVES VESICULAR HEPATIC STEATOSIS IN AN IN VITRO AND IN VIVO MODEL. NON-ALCOHOLIC FATTY LIVER DISEASE (NAFLD) IS A LEADING CAUSE OF CHRONIC LIVER DISEASE. ALTHOUGH GENETIC PREDISPOSITION AND EPIGENETIC FACTORS CONTRIBUTE TO THE DEVELOPMENT OF NAFLD, OUR UNDERSTANDING OF THE MOLECULAR MECHANISM INVOLVED IN THE PATHOGENESIS OF THE DISEASE IS STILL EMERGING. HERE WE INVESTIGATED A POSSIBLE ROLE OF A MICRORNAS-STAT3 PATHWAY IN THE INDUCTION OF HEPATIC STEATOSIS. DIFFERENTIATED HEPARG CELLS TREATED WITH THE FATTY ACID SODIUM OLEATE (FATTY DHEPARG) RECAPITULATED FEATURES OF LIVER VESICULAR STEATOSIS AND ACTIVATED A CELL-AUTONOMOUS INFLAMMATORY RESPONSE, INDUCING STAT3-TYROSINE-PHOSPHORYLATION. WITH A GENOME-WIDE APPROACH (CHROMATIN IMMUNOPRECIPITATION SEQUENCING), MANY PHOSPHO-STAT3 BINDING SITES WERE IDENTIFIED IN FATTY DHEPARG CELLS AND SEVERAL STAT3 AND/OR NAFLD-REGULATED MICRORNAS SHOWED INCREASED EXPRESSION LEVELS, INCLUDING MIR-21. INNOVATIVE CARS (COHERENT ANTI-STOKES RAMAN SCATTERING) MICROSCOPY REVEALED THAT CHEMICAL INHIBITION OF STAT3 ACTIVITY DECREASED LIPID ACCUMULATION AND DEREGULATED STAT3-RESPONSIVE MICRORNAS, INCLUDING MIR-21, IN LIPID OVERLOADED DHEPARG CELLS. WE WERE ABLE TO SHOW IN VIVO THAT REDUCING PHOSPHO-STAT3-MIR-21 LEVELS IN C57/BL6 MICE LIVER, BY LONG-TERM TREATMENT WITH METFORMIN, PROTECTED MICE FROM AGING-DEPENDENT HEPATIC VESICULAR STEATOSIS. OUR RESULTS IDENTIFIED A MICRORNAS-PHOSPHOSTAT3 PATHWAY INVOLVED IN THE DEVELOPMENT OF HEPATIC STEATOSIS, WHICH MAY REPRESENT A MOLECULAR MARKER FOR BOTH DIAGNOSIS AND THERAPEUTIC TARGETING. 2018 19 5575 30 ROLE OF MICRORNAS IN SIGNALING PATHWAYS ASSOCIATED WITH THE PATHOGENESIS OF IDIOPATHIC PULMONARY FIBROSIS: A FOCUS ON EPITHELIAL-MESENCHYMAL TRANSITION. IDIOPATHIC PULMONARY FIBROSIS (IPF) IS A CHRONIC AND PROGRESSIVE DISEASE WITH HIGH MORTALITY AND UNCLEAR ETIOLOGY. PREVIOUS EVIDENCE SUPPORTS THAT THE ORIGIN OF THIS DISEASE IS ASSOCIATED WITH EPIGENETIC ALTERATIONS, AGE, AND ENVIRONMENTAL FACTORS. IPF INITIATES WITH CHRONIC EPITHELIAL LUNG INJURIES, FOLLOWED BY BASAL MEMBRANE DESTRUCTION, WHICH PROMOTES THE ACTIVATION OF MYOFIBROBLASTS AND EXCESSIVE SYNTHESIS OF EXTRACELLULAR MATRIX (ECM) PROTEINS, AS WELL AS EPITHELIAL-MESENCHYMAL TRANSITION (EMT). DUE TO MIRNAS' ROLE AS REGULATORS OF APOPTOSIS, PROLIFERATION, DIFFERENTIATION, AND CELL-CELL INTERACTION PROCESSES, SOME STUDIES HAVE INVOLVED MIRNAS IN THE BIOGENESIS AND PROGRESSION OF IPF. IN THIS CONTEXT, THE ANALYSIS AND DISCUSSION OF THE PROBABLE ASSOCIATION OF MIRNAS WITH THE SIGNALING PATHWAYS INVOLVED IN THE DEVELOPMENT OF IPF WOULD IMPROVE OUR KNOWLEDGE OF THE ASSOCIATED MOLECULAR MECHANISMS, THEREBY FACILITATING ITS EVALUATION AS A THERAPEUTIC TARGET FOR THIS SEVERE LUNG DISEASE. IN THIS WORK, THE MOST RECENT PUBLICATIONS EVALUATING THE ROLE OF MIRNAS AS REGULATORS OR ACTIVATORS OF SIGNAL PATHWAYS ASSOCIATED WITH THE PATHOGENESIS OF IPF WERE ANALYZED. THE SEARCH IN PUBMED WAS MADE USING THE FOLLOWING TERMS: "MIRNAS AND IDIOPATHIC PULMONARY FIBROSIS (IPF)"; "MIRNAS AND IPF AND SIGNALING PATHWAYS (SP)"; AND "MIRNAS AND IPF AND SP AND IPF PATHOGENESIS". ADDITIONALLY, WE FOCUS MAINLY ON THOSE WORKS WHERE THE SIGNALING PATHWAYS INVOLVED WITH EMT, FIBROBLAST DIFFERENTIATION, AND SYNTHESIS OF ECM COMPONENTS WERE ASSESSED. FINALLY, THE IMPORTANCE AND SIGNIFICANCE OF MIRNAS AS POTENTIAL THERAPEUTIC OR DIAGNOSTIC TOOLS FOR THE TREATMENT OF IPF ARE DISCUSSED. 2022 20 2940 28 GENETIC AND EPIGENETIC ALTERATIONS IN NORMAL AND SENSITIVE COPD-DISEASED HUMAN BRONCHIAL EPITHELIAL CELLS REPEATEDLY EXPOSED TO AIR POLLUTION-DERIVED PM(2.5). EVEN THOUGH CLINICAL, EPIDEMIOLOGICAL AND TOXICOLOGICAL STUDIES HAVE PROGRESSIVELY PROVIDED A BETTER KNOWLEDGE OF THE UNDERLYING MECHANISMS BY WHICH AIR POLLUTION-DERIVED PARTICULATE MATTER (PM) EXERTS ITS HARMFUL HEALTH EFFECTS, FURTHER IN VITRO STUDIES ON RELEVANT CELL SYSTEMS ARE STILL NEEDED. HENCE, AIMING OF GETTING CLOSER TO THE HUMAN IN VIVO CONDITIONS, PRIMARY HUMAN BRONCHIAL EPITHELIAL CELLS DERIVED FROM NORMAL SUBJECTS (NHBE) OR SENSITIVE CHRONIC OBSTRUCTIVE PULMONARY DISEASE (COPD)-DISEASED PATIENTS (DHBE) WERE DIFFERENTIATED AT THE AIR-LIQUID INTERFACE. THEREAFTER, THEY WERE REPEATEDLY EXPOSED TO AIR POLLUTION-DERIVED PM(2.5) TO STUDY THE OCCURRENCE OF SOME RELEVANT GENETIC AND/OR EPIGENETIC ENDPOINTS. CONCENTRATION-, EXPOSURE- AND SEASON-DEPENDENT INCREASES OF OH-B[A]P METABOLITES IN NHBE, AND TO A LESSER EXTENT, COPD-DHBE CELLS WERE REPORTED; HOWEVER, THERE WERE MORE TETRA-OH-B[A]P AND 8-OHDG DNA ADDUCTS IN COPD-DHBE CELLS. NO INCREASE IN PRIMARY DNA STRAND BREAK NOR CHROMOSOMAL ABERRATION WAS OBSERVED IN REPEATEDLY EXPOSED CELLS. TELOMERE LENGTH AND TELOMERASE ACTIVITY WERE MODIFIED IN A CONCENTRATION- AND EXPOSURE-DEPENDENT MANNER IN NHBE AND PARTICULARLY COPD-DHBE CELLS. THERE WERE A GLOBAL DNA HYPOMETHYLATION, A P16 GENE PROMOTER HYPERMETHYLATION, AND A DECREASING DNA METHYLTRANSFERASE ACTIVITY IN NHBE AND NOTABLY COPD-DHBE CELLS REPEATEDLY EXPOSED. CHANGES IN SITE-SPECIFIC METHYLATION, ACETYLATION, AND PHOSPHORYLATION OF HISTONE H3 (I.E., H3K4ME3, H3K9AC, H3K27AC, AND H3S10PH) AND RELATED ENZYME ACTIVITIES OCCURRED IN A CONCENTRATION- AND EXPOSURE-DEPENDENT MANNER IN ALL THE REPEATEDLY EXPOSED CELLS. COLLECTIVELY, THESE RESULTS HIGHLIGHTED THE KEY ROLE PLAYED BY GENETIC AND EVEN EPIGENETIC EVENTS IN NHBE AND PARTICULARLY SENSITIVE COPD-DHBE CELLS REPEATEDLY EXPOSED TO AIR POLLUTION-DERIVED PM(2.5) AND THEIR DIFFERENT RESPONSIVENESS. WHILE THESE SPECIFIC EPIGENETIC CHANGES HAVE BEEN ALREADY DESCRIBED IN COPD AND EVEN LUNG CANCER PHENOTYPES, OUR FINDINGS SUPPORTED THAT, TOGETHER WITH GENETIC EVENTS, THESE EPIGENETIC EVENTS COULD DRAMATICALLY CONTRIBUTE TO THE SHIFT FROM HEALTHY TO DISEASED PHENOTYPES FOLLOWING REPEATED EXPOSURE TO RELATIVELY LOW DOSES OF AIR POLLUTION-DERIVED PM(2.5). 2017