1 3164 140 GREEN TEA PREVENTS NAFLD BY MODULATION OF MIR-34A AND MIR-194 EXPRESSION IN A HIGH-FAT DIET MOUSE MODEL. BACKGROUND/AIMS: NONALCOHOLIC FATTY LIVER DISEASE (NAFLD) IS CONSIDERED THE HEPATIC MANIFESTATION OF METABOLIC SYNDROME. IT IS CURRENTLY THE MOST COMMON CHRONIC LIVER DISEASE WITH COMPLEX PATHOGENESIS AND CHALLENGING TREATMENT. HERE, WE INVESTIGATED THE HEPATOPROTECTIVE ROLE OF GREEN TEA (GT) AND DETERMINED THE INVOLVEMENT OF MIRNAS AND ITS MECHANISM OF ACTION. METHODS: MALE C57BL/6 MICE WERE FED WITH A HIGH-FAT DIET FOR 4 WEEKS. AFTER THIS PERIOD, THE ANIMALS RECEIVED GAVAGE WITH GT (500 MG/KG BODY WEIGHT) OVER 12 WEEKS (5 DAYS/WEEK). HEPG2 CELL LINES WERE TRANSFECTED WITH MIR-34A OR MIR-194 MIMETICS AND INHIBITORS TO VALIDATE THE IN VIVO RESULTS OR WERE TREATED WITH TNF-ALPHA TO EVALUATE MIRNA REGULATION. RESULTS: GT SUPPLEMENTATION PROTECTS AGAINST NAFLD DEVELOPMENT BY ALTERING LIPID METABOLISM, INCREASING GENE EXPRESSION INVOLVED IN TRIGLYCERIDES AND FATTY ACID CATABOLISM, AND DECREASING UPTAKE AND LIPID ACCUMULATION. THIS PHENOTYPE WAS ACCOMPANIED BY MIR-34A DOWNREGULATION AND AN INCREASE IN THEIR MRNA TARGETS SIRT1, PPARALPHA, AND INSIG2. GT UPREGULATED HEPATIC MIR-194 BY INHIBITING TNF-ALPHA ACTION LEADING TO A DECREASE IN MIR-194 TARGET GENES HMGCS/APOA5. CONCLUSION: OUR STUDY IDENTIFIED FOR THE FIRST TIME THAT THE BENEFICIAL EFFECTS OF GT IN THE LIVER CAN BE DUE TO THE MODULATION OF MIRNAS, OPENING NEW PERSPECTIVES FOR THE TREATMENT OF NAFLD FOCUSING ON EPIGENETIC REGULATION OF MIR-34A AND MIR-194 AS GREEN TEA TARGETS. 2019 2 3241 53 HEPATIC MICRORNA MODULATION MIGHT BE AN EARLY EVENT TO NON-ALCOHOLIC FATTY LIVER DISEASE DEVELOPMENT DRIVEN BY HIGH-FAT DIET IN MALE MICE. INTRODUCTION: METABOLIC ALTERATIONS CAUSED BY AN IMBALANCE OF MACRONUTRIENT CONSUMPTION ARE OFTEN RELATED TO THE MODULATION OF MICRORNAS (MIRNAS), WHICH COULD ALTER MRNAS EXPRESSION PROFILE AND ACCELERATE THE DEVELOPMENT OF NON-ALCOHOLIC FATTY LIVER DISEASE (NAFLD). AIMS: THIS STUDY AIMED TO INVESTIGATE THE CONTRIBUTION OF MIRNAS IN MODULATING EARLY STAGES OF NAFLD IN MICE SUBMITTED TO A HIGH-FAT DIET (HFD). METHODS AND RESULTS: MALE SWISS MICE, FED EITHER A CONTROL DIET OR AN HFD FOR 1, 3, 7, 15, 30, 56 DAYS, WERE ASSESSED FOR METABOLIC ALTERATIONS, GENE EXPRESSION AND NAFLD MARKERS. A HEPATOCYTE CELL LINE WAS USED TO INVESTIGATE THE EFFECTS OF MIR-370 MODULATION ON ENZYMES INVOLVED IN BETA-OXIDATION. BODY WEIGHT AND ADIPOSITY WERE HIGHER AFTER 7 DAYS OF HFD. FASTING GLUCOSE AND INSULIN INCREASED AFTER 3 AND 7 DAYS OF HFD, RESPECTIVELY. WHILE HEPATIC LIPID CONTENT INCREASED FROM THE FIRST DAY ON, HEPATIC GLYCOGEN HAD A DECREASE AFTER 3 DAYS OF HFD CONSUMPTION. MIR-370 AND LET-7 EXPRESSION INCREASED WITH ACUTE AND CHRONIC EXPOSURE TO HFD, ACCOMPANIED BY CARNITINE PALMITOYLTRANSFERASE 1A (CPT1A), ACYL-COA DEHYDROGENASE VERY LONG CHAIN (ACADVL) AND PROTEIN KINASE AMP-ACTIVATED CATALYTIC SUBUNIT 2 (PRKAA2) DOWNREGULATION, WHILE DECREASED MIR-122 EXPRESSION WAS ACCOMPANIED BY 1-ACYLGLYCEROL-3-PHOSPHATE-O-ACYLTRANSFERASE (AGPAT) UPREGULATION AFTER 56 DAYS OF HFD CONSUMPTION, SOME OF THEM CONFIRMED BY IN VITRO EXPERIMENTS. DESPITE FLUCTUATIONS IN TNFA AND IL6 MRNA LEVELS, MOLECULAR MODULATION WAS CONSISTENT WITH HEPATIC TG AND NAFLD DEVELOPMENT. CONCLUSION: HEPATIC MIR-370-122-LET7 MIRNA MODULATION COULD BE THE FIRST INSULT TO NAFLD DEVELOPMENT, PRECEDING CHANGES IN GLYCEMIC HOMEOSTASIS AND ADIPOSITY. 2022 3 4286 51 MICRORNA EXPRESSION ANALYSIS IN HIGH FAT DIET-INDUCED NAFLD-NASH-HCC PROGRESSION: STUDY ON C57BL/6J MICE. BACKGROUND: HEPATOCELLULAR CARCINOMA (HCC) IS THE MOST COMMON MALIGNANT TUMOR OF THE LIVER. NON-ALCOHOLIC FATTY LIVER DISEASE (NAFLD) IS A FREQUENT CHRONIC LIVER DISORDER IN DEVELOPED COUNTRIES. NAFLD CAN PROGRESS THROUGH THE MORE SEVERE NON ALCOHOLIC STEATOHEPATITIS (NASH), CIRRHOSIS AND, LASTLY, HCC. GENETIC AND EPIGENETIC ALTERATIONS OF CODING GENES AS WELL AS DEREGULATION OF MICRORNAS (MIRNAS) ACTIVITY PLAY A ROLE IN HCC DEVELOPMENT. IN THIS STUDY, THE C57BL/6J MOUSE MODEL WAS LONG TERM HIGH-FAT (HF) OR LOW-FAT (LF) DIET FED, IN ORDER TO ANALYZE MOLECULAR MECHANISMS RESPONSIBLE FOR THE HEPATIC DAMAGE PROGRESSION. METHODS: MICE WERE HF OR LF DIET FED FOR DIFFERENT TIME POINTS, THEN PLASMA AND HEPATIC TISSUES WERE COLLECTED. HISTOLOGICAL AND CLINICAL CHEMISTRY ASSAYS WERE PERFORMED TO ASSESS THE PROGRESSION OF LIVER DISEASE. MICRORNAS' DIFFERENTIAL EXPRESSION WAS EVALUATED ON POOLED RNAS FROM TISSUES, AND SOME MIRNAS SHOWING DYSREGULATION WERE FURTHER ANALYZED AT THE INDIVIDUAL LEVEL. RESULTS: CHOLESTEROL, LOW AND HIGH DENSITY LIPOPROTEINS, TRIGLYCERIDES AND ALANINE AMINOTRANSFERASE INCREASE WAS DETECTED IN HF MICE. GROSS ANATOMICAL EXAMINATION REVEALED HEPATOMEGALY IN HF LIVERS, AND HISTOLOGICAL ANALYSIS HIGHLIGHTED DIFFERENT DEGREES AND LEVELS OF STEATOSIS, INFLAMMATORY INFILTRATE AND FIBROSIS IN HF AND LF ANIMALS, DEMONSTRATING THE PROGRESSION FROM NAFLD THROUGH NASH. MACROSCOPIC NODULES, SHOWING TYPICAL NEOPLASTIC FEATURES, WERE OBSERVED IN 20% OF HF DIET FED MICE. FIFTEEN MIRNAS DIFFERENTIALLY EXPRESSED IN HF WITH RESPECT TO LF HEPATIC TISSUES DURING THE PROGRESSION OF LIVER DAMAGE, AND IN TUMORS WITH RESPECT TO HF NON TUMOR LIVER SPECIMENS WERE IDENTIFIED. AMONG THEM, MIR-340-5P, MIR-484, MIR-574-3P, MIR-720, WHOSE EXPRESSION WAS NEVER DESCRIBED IN NAFLD, NASH AND HCC TISSUES, AND MIR-125A-5P AND MIR-182, WHICH SHOWED EARLY AND SIGNIFICANT DYSREGULATION IN THE SEQUENTIAL HEPATIC DAMAGE PROCESS. CONCLUSIONS: IN THIS STUDY, FIFTEEN MICRORNAS WHICH WERE MODULATED IN HEPATIC TISSUES AND IN TUMORS DURING THE TRANSITION NAFLD-NASH-HCC ARE REPORTED. BESIDES SOME ALREADY DESCRIBED, NEW AND EARLY DYSREGULATED MIRNAS WERE IDENTIFIED. FUNCTIONAL ANALYSES ARE NEEDED TO VALIDATE THE RESULTS HERE OBTAINED, AND TO BETTER DEFINE THE ROLE OF THESE MOLECULES IN THE PROGRESSION OF THE HEPATIC DISEASE. 2016 4 2780 39 EZH2 DOWN-REGULATION EXACERBATES LIPID ACCUMULATION AND INFLAMMATION IN IN VITRO AND IN VIVO NAFLD. NON-ALCOHOLIC FATTY LIVER DISEASE (NAFLD) IS ONE OF THE MOST PREVALENT, CHRONIC LIVER DISEASES, WORLDWIDE. IT IS A MULTIFACTORIAL DISEASE CAUSED BY COMPLEX INTERACTIONS BETWEEN GENETIC, EPIGENETIC AND ENVIRONMENTAL FACTORS. RECENTLY, SEVERAL MICRORNAS, SOME OF WHICH EPIGENETICALLY REGULATED, HAVE BEEN FOUND TO BE UP- AND/OR DOWN-REGULATED DURING NAFLD DEVELOPMENT. HOWEVER, IN NAFLD, THE ESSENTIAL ROLE OF THE POLYCOMB GROUP PROTEIN ENHANCER OF ZESTE HOMOLOG 2 (EZH2), WHICH CONTROLS THE EPIGENETIC SILENCING OF SPECIFIC GENES AND/OR MICRORNAS BY TRIMETHYLATING LYS27 ON HISTONE H3, STILL REMAINS UNKNOWN. IN THIS STUDY, WE DEMONSTRATE THAT THE NUCLEAR EXPRESSION/ACTIVITY OF THE EZH2 PROTEIN IS DOWN-REGULATED BOTH IN LIVERS FROM NAFLD RATS AND IN THE FREE FATTY ACID-TREATED HEPG2. THE DROP IN EZH2 IS INVERSELY CORRELATED WITH: (I) LIPID ACCUMULATION; (II) THE EXPRESSION OF PRO-INFLAMMATORY MARKERS INCLUDING TNF-ALPHA AND TGF-BETA; AND (III) THE EXPRESSION OF MIR-200B AND MIR-155. CONSISTENTLY, THE PHARMACOLOGICAL INHIBITION OF EZH2 BY 3-DEAZANEPLANOCIN A (DZNEP) SIGNIFICANTLY REDUCES EZH2 EXPRESSION/ACTIVITY, WHILE IT INCREASES LIPID ACCUMULATION, INFLAMMATORY MOLECULES AND MICRORNAS. IN CONCLUSION, THE RESULTS OF THIS STUDY SUGGEST THAT THE DEFECTIVE ACTIVITY OF EZH2 CAN ENHANCE THE NAFLD DEVELOPMENT BY FAVOURING STEATOSIS AND THE DE-REPRESSION OF THE INFLAMMATORY GENES AND THAT OF SPECIFIC MICRORNAS. 2013 5 5150 42 PPARALPHA IN THE EPIGENETIC DRIVER SEAT OF NAFLD: NEW THERAPEUTIC OPPORTUNITIES FOR EPIGENETIC DRUGS? NONALCOHOLIC FATTY LIVER DISEASE (NAFLD) IS A GROWING EPIDEMIC AND THE MOST COMMON CAUSE OF CHRONIC LIVER DISEASE WORLDWIDE. IT CONSISTS OF A SPECTRUM OF LIVER DISORDERS RANGING FROM SIMPLE STEATOSIS TO NASH WHICH PREDISPOSES PATIENTS TO FURTHER FIBROSIS, CIRRHOSIS AND EVEN HEPATOCARCINOMA. DESPITE MUCH RESEARCH, AN APPROVED TREATMENT IS STILL LACKING. FINDING NEW THERAPEUTIC TARGETS HAS THEREFORE BEEN A MAIN PRIORITY. KNOWN AS A MAIN REGULATOR OF THE LIPID METABOLISM AND HIGHLY EXPRESSED IN THE LIVER, THE NUCLEAR RECEPTOR PEROXISOME PROLIFERATOR-ACTIVATED RECEPTOR-ALPHA (PPARALPHA) HAS BEEN IDENTIFIED AS AN ATTRACTIVE THERAPEUTIC TARGET. SINCE ITS EXPRESSION IS SILENCED BY DNA HYPERMETHYLATION IN NAFLD PATIENTS, MANY RESEARCH STRATEGIES HAVE AIMED TO RESTORE THE EXPRESSION OF PPARALPHA AND ITS TARGET GENES INVOLVED IN LIPID METABOLISM. ALTHOUGH PREVIOUSLY TESTED PPARALPHA AGONISTS DID NOT AMELIORATE THE DISEASE, CURRENT RESEARCH HAS SHOWN THAT PPARALPHA ALSO INTERACTS AND REGULATES EPIGENETIC DNMT1, JMJD3, TET AND SIRT1 ENZYMES. MOREOVER, THERE IS A GROWING BODY OF EVIDENCE SUGGESTING THE ORCHESTRATING ROLE OF EPIGENETICS IN THE DEVELOPMENT AND PROGRESSION OF NAFLD. THEREFORE, CURRENT THERAPEUTIC STRATEGIES ARE SHIFTING MORE TOWARDS EPIGENETIC DRUGS. THIS REVIEW PROVIDES A CONCISE OVERVIEW OF THE EPIGENETIC REGULATION OF NAFLD WITH A FOCUS ON PPARALPHA REGULATION AND HIGHLIGHTS RECENTLY IDENTIFIED EPIGENETIC INTERACTION PARTNERS OF PPARALPHA. 2022 6 5438 39 REMOVAL OF EPIGENETIC REPRESSIVE MARK ON INFLAMMATORY GENES IN FAT LIVER. NONALCOHOLIC FATTY LIVER DISEASE (NAFLD) IS THE MOST COMMON CHRONIC LIVER DISEASE WORLDWIDE. THE DETAILED EPIGENOMIC CHANGES DURING FAT ACCUMULATION IN LIVER ARE NOT CLEAR YET. HERE, WE PERFORMED CHIP-SEQ ANALYSIS IN THE LIVER TISSUES OF HIGH-FAT DIET AND REGULAR CHOW DIET MICE AND INVESTIGATED THE DYNAMIC LANDSCAPES OF H3K27AC AND H3K9ME3 MARKS ON CHROMATIN. WE FIND THAT THE ACTIVATED TYPICAL ENHANCERS MARKED WITH H3K27AC ARE ENRICHED ON LIPID METABOLIC PATHWAYS IN FAT LIVER; HOWEVER, SUPER ENHANCERS DO NOT CHANGE MUCH. THE REGIONS COVERED WITH H3K9ME3 REPRESSIVE MARK SEEM TO UNDERGO GREAT CHANGES, AND ITS PEAK NUMBER AND INTENSITY BOTH DECREASE IN FAT LIVER. THE ENHANCERS LOCATED IN LOST H3K9ME3 REGIONS ARE ENRICHED IN LIPID METABOLISM AND INFLAMMATORY PATHWAYS; AND MOTIF ANALYSIS SHOWS THAT THEY ARE POTENTIAL TARGETS FOR TRANSCRIPTION FACTORS INVOLVED IN METABOLIC AND INFLAMMATORY PROCESSES. OUR STUDY HAS REVEALED THAT H3K9ME3 MAY PLAY AN IMPORTANT ROLE DURING THE PATHOGENESIS OF NAFLD THROUGH REGULATING THE ACCESSIBILITY OF ENHANCERS. 2023 7 1666 55 DOWNREGULATION OF MICRORNA-145A-5P PROMOTES STEATOSIS-TO-NASH PROGRESSION THROUGH UPREGULATION OF NR4A2. BACKGROUND & AIMS: THE MOLECULAR MECHANISMS UNDERLYING THE PROGRESSION OF SIMPLE STEATOSIS TO NON-ALCOHOLIC STEATOHEPATITIS (NASH) REMAIN INCOMPLETELY UNDERSTOOD, THOUGH THE POTENTIAL ROLE OF EPIGENETIC REGULATION BY MICRORNA (MIRNAS) IS AN AREA OF INCREASING INTEREST. IN THE PRESENT STUDY, WE AIMED TO INVESTIGATE THE ROLE AND MECHANISM OF MIRNAS DURING STEATOSIS-TO-NASH PROGRESSION. METHODS: MIR-145A-5P WAS IDENTIFIED AS AN IMPORTANT CHECKPOINT IN STEATOSIS-TO-NASH PROGRESSION. IN VIVO LOSS-OF-FUNCTION AND GAIN-OF-FUNCTION STUDIES WERE PERFORMED TO EXPLORE THE ROLE OF MIR-145A-5P AND NR4A2 IN NASH PROGRESSION. RNA-SEQUENCING AND BIOINFORMATIC ANALYSIS WERE USED TO INVESTIGATE THE TARGETS OF MIR-145A-5P. RESULTS: SUPPRESSION OF MIR-145A-5P IN THE LIVER AGGRAVATED LIPID ACCUMULATION AND ACTIVATED HEPATIC INFLAMMATION, LIVER INJURY AND FIBROSIS IN STEATOTIC MICE, WHEREAS ITS RESTORATION MARKEDLY ATTENUATED DIET-INDUCED NASH PATHOGENESIS. MECHANISTICALLY, MIR-145A-5P WAS ABLE TO DOWNREGULATE THE NUCLEAR RECEPTOR NR4A2 AND THUS INHIBIT THE EXPRESSION OF NASH-ASSOCIATED GENES. SIMILARLY, NR4A2 OVEREXPRESSION PROMOTED STEATOSIS-TO-NASH PROGRESSION WHILE LIVER-SPECIFIC NR4A2 KNOCKOUT MICE WERE PROTECTED FROM DIET-INDUCED NASH. THIS ROLE OF THE MIR-145A-5P/NR4A2 REGULATORY AXIS WAS ALSO CONFIRMED IN PRIMARY HUMAN HEPATOCYTES. FURTHERMORE, THE EXPRESSION OF MIR-145A-5P WAS REDUCED AND THE EXPRESSION OF NR4A2 WAS INCREASED IN THE LIVERS OF PATIENTS WITH NASH, WHILE THEIR EXPRESSION LEVELS SIGNIFICANTLY NEGATIVELY AND POSITIVELY CORRELATED WITH FEATURES OF LIVER PATHOLOGY, RESPECTIVELY. CONCLUSIONS: OUR FINDINGS HIGHLIGHT THE ROLE OF THE MIR-145A-5P/NR4A2 REGULATORY AXIS IN STEATOSIS-TO-NASH PROGRESSION, SUGGESTING THAT EITHER SUPPLEMENTATION OF MIR-145A-5P OR PHARMACOLOGICAL INHIBITION OF NR4A2 IN HEPATOCYTES MAY PROVIDE A PROMISING THERAPEUTIC APPROACH FOR THE TREATMENT OF NASH. IMPACT AND IMPLICATIONS: NON-ALCOHOLIC FATTY LIVER DISEASE (NAFLD) IS A DYNAMIC SPECTRUM OF CHRONIC LIVER DISEASES RANGING FROM SIMPLE STEATOSIS TO NON-ALCOHOLIC STEATOHEPATITIS (NASH). UNFORTUNATELY, THERE ARE CURRENTLY NO APPROVED DRUGS FOR NASH. OUR CURRENT STUDY IDENTIFIED MIR-145A-5P AS A NOVEL REGULATOR THAT INHIBITS STEATOSIS-TO-NASH PROGRESSION. WE FOUND THAT MIR-145A-5P WAS ABLE TO DOWNREGULATE THE NUCLEAR RECEPTOR NR4A2 TO SUPPRESS THE EXPRESSION OF NASH-ASSOCIATED GENES. THE DIFFERENTIAL EXPRESSION OF MIR-145A-5P AND NR4A2 WAS FURTHER CONFIRMED IN PATIENTS WITH NASH, RAISING THE POSSIBILITY THAT SUPPLEMENTATION OF MIR-145A-5P OR SUPPRESSION OF NR4A2 IN HEPATOCYTES MIGHT PROVIDE NOVEL STRATEGIES FOR TREATING NASH. 2023 8 5305 45 PROTEOMICS ANALYSIS OF HUMAN OBESITY REVEALS THE EPIGENETIC FACTOR HDAC4 AS A POTENTIAL TARGET FOR OBESITY. SEDENTARY LIFESTYLE AND EXCESSIVE ENERGY INTAKE ARE PROMINENT CONTRIBUTORS TO OBESITY; A MAJOR RISK FACTORS FOR THE DEVELOPMENT OF INSULIN RESISTANCE, TYPE 2 DIABETES AND CARDIOVASCULAR DISEASES. ELUCIDATING THE MOLECULAR MECHANISMS UNDERLYING THESE CHRONIC CONDITIONS IS OF RELEVANT IMPORTANCE AS IT MIGHT LEAD TO THE IDENTIFICATION OF NOVEL ANTI-OBESITY TARGETS. THE PURPOSE OF THE CURRENT STUDY IS TO INVESTIGATE DIFFERENTIALLY EXPRESSED PROTEINS BETWEEN LEAN AND OBESE SUBJECTS THROUGH A SHOT-GUN QUANTITATIVE PROTEOMICS APPROACH USING PERIPHERAL BLOOD MONONUCLEAR CELLS (PBMCS) EXTRACTS AS WELL AS POTENTIAL MODULATION OF THOSE PROTEINS BY PHYSICAL EXERCISE. USING THIS APPROACH, A TOTAL OF 47 PROTEINS SHOWED AT LEAST 1.5 FOLD CHANGE BETWEEN LEAN AND OBESE SUBJECTS. IN OBESE, THE PROTEOMIC PROFILING BEFORE AND AFTER 3 MONTHS OF PHYSICAL EXERCISE SHOWED DIFFERENTIAL EXPRESSION OF 38 PROTEINS. THROMBOSPONDIN 1 (TSP1) WAS AMONG THE PROTEINS THAT WERE UPREGULATED IN OBESE SUBJECTS AND THEN DECREASED BY PHYSICAL EXERCISE. CONVERSELY, THE HISTONE DEACETYLASE 4 (HDAC4) WAS DOWNREGULATED IN OBESE SUBJECTS AND THEN INDUCED BY PHYSICAL EXERCISE. THE PROTEOMIC DATA WAS FURTHER VALIDATED BY QRT-PCR, WESTERN BLOT AND IMMUNOHISTOCHEMISTRY IN BOTH PBMCS AND ADIPOSE TISSUE. WE ALSO SHOWED THAT HDAC4 LEVELS CORRELATED POSITIVELY WITH MAXIMUM OXYGEN CONSUMPTION (VO2 MAX) BUT NEGATIVELY WITH BODY MASS INDEX, PERCENT BODY FAT, AND THE INFLAMMATORY CHEMOKINE RANTES. IN FUNCTIONAL ASSAYS, OUR DATA INDICATED THAT ECTOPIC EXPRESSION OF HDAC4 SIGNIFICANTLY IMPAIRED TNF-ALPHA-DEPENDENT ACTIVATION OF NF-KAPPAB, ESTABLISHING THUS A LINK BETWEEN HDAC4 AND REGULATION OF THE IMMUNE SYSTEM. TOGETHER, THE EXPRESSION PATTERN OF HDAC4 IN OBESE SUBJECTS BEFORE AND AFTER PHYSICAL EXERCISE, ITS CORRELATION WITH VARIOUS PHYSICAL, CLINICAL AND METABOLIC PARAMETERS ALONG WITH ITS INHIBITORY EFFECT ON NF-KAPPAB ARE SUGGESTIVE OF A PROTECTIVE ROLE OF HDAC4 AGAINST OBESITY. HDAC4 COULD THEREFORE REPRESENT A POTENTIAL THERAPEUTIC TARGET FOR THE CONTROL AND MANAGEMENT OF OBESITY AND PRESUMABLY INSULIN RESISTANCE. 2013 9 3292 43 HIGH FAT DIET AND EXERCISE LEAD TO A DISRUPTED AND PATHOGENIC DNA METHYLOME IN MOUSE LIVER. HIGH-FAT DIET CONSUMPTION AND SEDENTARY LIFESTYLE ELEVATES RISK FOR OBESITY, NON-ALCOHOLIC FATTY LIVER DISEASE, AND CANCER. EXERCISE TRAINING CONVEYS HEALTH BENEFITS IN POPULATIONS WITH OR WITHOUT THESE CHRONIC CONDITIONS. DIET AND EXERCISE REGULATE GENE EXPRESSION BY MEDIATING EPIGENETIC MECHANISMS IN MANY TISSUES; HOWEVER, SUCH EFFECTS ARE POORLY DOCUMENTED IN THE LIVER, A CENTRAL METABOLIC ORGAN. TO DISSECT THE CONSEQUENCES OF DIET AND EXERCISE ON THE LIVER EPIGENOME, WE MEASURED DNA METHYLATION, USING REDUCED REPRESENTATION BISULFITE SEQUENCING, AND TRANSCRIPTION, USING RNA-SEQ, IN MICE MAINTAINED ON A FAST FOOD DIET WITH SEDENTARY LIFESTYLE OR EXERCISE, COMPARED WITH CONTROL DIET WITH AND WITHOUT EXERCISE. OUR ANALYSES REVEAL THAT GENOME-WIDE DIFFERENTIAL DNA METHYLATION AND EXPRESSION OF GENE CLUSTERS ARE INDUCED BY DIET AND/OR EXERCISE. A COMBINATION OF FAST FOOD AND EXERCISE TRIGGERS EXTENSIVE GENE ALTERATIONS, WITH ENRICHMENT OF CARBOHYDRATE/LIPID METABOLIC PATHWAYS AND MUSCLE DEVELOPMENTAL PROCESSES. THROUGH EVALUATION OF PUTATIVE PROTECTIVE EFFECTS OF EXERCISE ON DIET-INDUCED DNA METHYLATION, WE SHOW THAT HYPERMETHYLATION IS EFFECTIVELY PREVENTED, ESPECIALLY AT PROMOTERS AND ENHANCERS, WHEREAS HYPOMETHYLATION IS ONLY PARTIALLY ATTENUATED. WE ASSESSED DIET-INDUCED DNA METHYLATION CHANGES ASSOCIATED WITH LIVER CANCER-RELATED EPIGENETIC MODIFICATIONS AND IDENTIFIED SIGNIFICANT INCREASES AT LIVER-SPECIFIC ENHANCERS IN FAST FOOD GROUPS, SUGGESTING PARTIAL LOSS OF LIVER CELL IDENTITY. HYPERMETHYLATION AT A SUBSET OF GENE PROMOTERS WAS ASSOCIATED WITH INHIBITION OF TISSUE DEVELOPMENT AND PROMOTION OF CARCINOGENIC PROCESSES. OUR STUDY DEMONSTRATES EXTENSIVE REPROGRAMMING OF THE EPIGENOME BY DIET AND EXERCISE, EMPHASIZING THE FUNCTIONAL RELEVANCE OF EPIGENETIC MECHANISMS AS AN INTERFACE BETWEEN LIFESTYLE MODIFICATIONS AND PHENOTYPIC ALTERATIONS. 2017 10 5074 38 PHYSIOLOGIC AND EPIGENETIC EFFECTS OF NUTRIENTS ON DISEASE PATHWAYS. BACKGROUND/OBJECTIVES: EPIGENETIC REGULATION BY NUTRIENTS CAN INFLUENCE THE DEVELOPMENT OF SPECIFIC DISEASES. THIS STUDY SOUGHT TO EXAMINE THE EFFECT OF INDIVIDUAL NUTRIENTS AND NUTRIENT FAMILIES IN THE CONTEXT OF PREVENTING CHRONIC METABOLIC DISEASES VIA EPIGENETIC REGULATION. THE INHIBITION OF LIPID ACCUMULATION AND INFLAMMATION BY NUTRIENTS INCLUDING PROTEINS, LIPIDS, VITAMINS, AND MINERALS WERE OBSERVED, AND HISTONE ACETYLATION BY HISTONE ACETYLTRANSFERASE (HAT) WAS MEASURED. CORRELATIVE ANALYSES WERE ALSO PERFORMED. MATERIALS/METHODS: NUTRIENTS WERE SELECTED ACCORDING TO INFORMATION FROM THE KOREAN MINISTRY OF FOOD AND DRUG SAFETY. SELECTED NUTRIENT FUNCTIONALITIES, INCLUDING THE ATTENUATION OF FATTY ACID-INDUCED LIPID ACCUMULATION AND LIPOPOLYSACCHARIDE-MEDIATED ACUTE INFLAMMATION WERE EVALUATED IN MOUSE MACROPHAGE RAW264.7 AND MOUSE HEPATOCYTE AML-12 CELLS. EFFECTS OF THE SELECTED NUTRIENTS ON IN VITRO HAT INHIBITION WERE ALSO EVALUATED. RESULTS: NITRIC OXIDE (NO) PRODUCTION CORRELATED WITH HAT ACTIVITY, WHICH WAS REGULATED BY THE AMINO ACIDS GROUP, SUGGESTING THAT AMINO ACIDS POTENTIALLY CONTRIBUTE TO THE ATTENUATION OF NO PRODUCTION VIA THE INHIBITION OF HAT ACTIVITY. UNSATURATED FATTY ACIDS TENDED TO ATTENUATE INFLAMMATION BY INHIBITING NO PRODUCTION, WHICH MAY BE ATTRIBUTABLE TO THE INHIBITION OF IN VITRO HAT ACTIVITY. IN CONTRAST TO WATER-SOLUBLE VITAMINS, THE LIPID-SOLUBLE VITAMINS SIGNIFICANTLY DECREASED NO PRODUCTION. WATER- AND LIPID-SOLUBLE VITAMINS BOTH EXHIBITED SIGNIFICANT INHIBITORY ACTIVITIES AGAINST HAT. IN ADDITION, CALCIUM AND MANGANESE SIGNIFICANTLY INHIBITED LIPID ACCUMULATION, NO PRODUCTION, AND HAT ACTIVITY. CONCLUSIONS: SEVERAL CANDIDATE NUTRIENTS AND THEIR FAMILY MEMBERS MAY HAVE ROLES IN THE PREVENTION OF DISEASES, INCLUDING HEPATIC STEATOSIS AND INFLAMMATION-RELATED DISEASES (I.E., NONALCOHOLIC STEATOHEPATITIS) VIA EPIGENETIC REGULATION. FURTHER STUDIES ARE WARRANTED TO DETERMINE WHICH SPECIFIC AMINO ACIDS, UNSATURATED FATTY ACIDS AND LIPID-SOLUBLE VITAMINS OR SPECIFIC MINERALS INFLUENCE THE DEVELOPMENT OF STEATOSIS AND INFLAMMATORY-RELATED DISEASES. 2023 11 413 41 ANALYSIS OF MIRNAS PROFILES IN SERUM OF PATIENTS WITH STEATOSIS AND STEATOHEPATITIS. NON-ALCOHOLIC FATTY LIVER DISEASE (NAFLD) IS EMERGING AS ONE OF THE MOST COMMON CHRONIC LIVER DISEASES WORLDWIDE, AFFECTING 25% OF THE WORLD POPULATION. IN RECENT YEARS, THERE HAS BEEN INCREASING EVIDENCE FOR THE INVOLVEMENT OF MICRORNAS IN THE EPIGENETIC REGULATION OF GENES TAKING PART IN THE DEVELOPMENT OF STEATOSIS AND STEATOHEPATITIS-TWO MAIN STAGES OF NAFLD PATHOGENESIS. IN THE PRESENT STUDY, MIRNA PROFILES WERE STUDIED IN GROUPS OF PATIENTS WITH STEATOSIS AND STEATOHEPATITIS TO COMPARE THE CHARACTERISTICS OF RNA-DEPENDENT EPIGENETIC REGULATION OF THE STAGES OF NAFLD DEVELOPMENT. ACCORDING TO THE RESULTS OF MIRNA SCREENING, 23 MIRNAS WERE DIFFERENTIALLY EXPRESSED SERUM IN A GROUP OF PATIENTS WITH STEATOHEPATITIS AND 2 IN A GROUP OF PATIENTS WITH STEATOSIS. MIR-195-5P AND MIR-16-5P ARE COMMON DIFFERENTIALLY EXPRESSED MIRNAS FOR BOTH STEATOSIS AND STEATOHEPATITIS. WE ANALYZED THE OBTAINED RESULTS: THE SEARCH FOR TARGET GENES FOR THE DIFFERENTIALLY EXPRESSED MIRNAS IN OUR STUDY AND THE SUBSEQUENT GENE SET ENRICHMENT ANALYSIS PERFORMED ON KEGG AND REACTOME DATABASES REVEALED WHICH METABOLIC PATHWAYS UNDERGO CHANGES IN RNA-DEPENDENT EPIGENETIC REGULATION IN STEATOSIS AND STEATOHEPATITIS. NEW FINDINGS WITHIN THE FRAMEWORK OF THIS STUDY ARE THE DYSREGULATION OF NEUROHUMORAL PATHWAYS IN THE PATHOGENESIS OF NAFLD AS AN OBJECT OF CHANGES IN RNA-DEPENDENT EPIGENETIC REGULATION. THE MIRNAS DIFFERENTIALLY EXPRESSED IN OUR STUDY WERE FOUND TO TARGET 7% OF GENES IN THE CLASSIC PATHOGENESIS OF NAFLD IN THE GROUP OF PATIENTS WITH STEATOSIS AND 50% IN THE GROUP OF PATIENTS WITH STEATOHEPATITIS. THE EFFECTS OF THESE MICRORNAS ON GENES FOR THE PATHOGENESIS OF NAFLD WERE ANALYZED IN DETAIL. MIR-374A-5P, MIR-1-3P AND MIR-23A-3P DO NOT TARGET GENES DIRECTLY INVOLVED IN THE PATHOGENESIS OF NAFLD. THE DIFFERENTIALLY EXPRESSED MIRNAS FOUND IN THIS STUDY TARGET GENES LARGELY RESPONSIBLE FOR MITOCHONDRIAL FUNCTION. THE ROLE OF MIR-423-5P, MIR-143-5P AND MIR-200C-3 IN REGULATING APOPTOTIC PROCESSES IN THE LIVER AND HEPATOCARCINOGENESIS IS OF INTEREST FOR FUTURE EXPERIMENTAL STUDIES. THESE MIR-374A, MIR-143, MIR-1, MIR-23A, AND MIR-423 HAVE POTENTIAL FOR STEATOHEPATITIS DIAGNOSIS AND ARE POORLY STUDIED IN THE CONTEXT OF NAFLD. THUS, THIS WORK OPENS UP PROSPECTS FOR FURTHER STUDIES OF MICRORNAS AS DIAGNOSTIC AND THERAPEUTIC BIOMARKERS FOR NAFLD. 2021 12 613 37 BINGE ALCOHOL ALTERS PNPLA3 LEVELS IN LIVER THROUGH EPIGENETIC MECHANISM INVOLVING HISTONE H3 ACETYLATION. THE HUMAN PNPLA3 (PATATIN-LIKE PHOSPHOLIPASE DOMAIN-CONTAINING 3) GENE CODES FOR A PROTEIN WHICH IS HIGHLY EXPRESSED IN ADIPOSE TISSUE AND LIVER, AND IS IMPLICATED IN LIPID HOMEOSTASIS. WHILE PNPLA3 PROTEIN CONTAINS REGIONS HOMOLOGOUS TO FUNCTIONAL LIPOLYTIC PROTEINS, THE REGULATION OF ITS TISSUE EXPRESSION IS REFLECTIVE OF LIPOGENIC GENES. A NATURALLY OCCURRING GENETIC VARIANT OF PNPLA3 IN HUMANS HAS BEEN LINKED TO INCREASED SUSCEPTIBILITY TO ALCOHOLIC LIVER DISEASE. WE HAVE EXAMINED THE MODULATORY EFFECT OF ALCOHOL ON PNPLA3 PROTEIN AND MRNA EXPRESSION AS WELL AS THE ASSOCIATION OF ITS GENE PROMOTER WITH ACETYLATED HISTONE H3K9 BY CHROMATIN IMMUNOPRECIPITATION (CHIP) ASSAY IN RAT HEPATOCYTES IN VITRO, AND IN VIVO IN MOUSE AND RAT MODELS OF ACUTE BINGE, CHRONIC, AND CHRONIC FOLLOWED BY ACUTE BINGE ETHANOL ADMINISTRATION. PROTEIN EXPRESSION OF PNPLA3 WAS SIGNIFICANTLY INCREASED BY ALCOHOL IN ALL THREE MODELS USED. PNPLA3 MRNA ALSO INCREASED, ALBEIT TO A VARYING DEGREE. CHIP ASSAY USING H3ACK9 ANTIBODY SHOWED INCREASED ASSOCIATION WITH THE PROMOTER OF PNPLA3 IN HEPATOCYTES AND IN MOUSE LIVER. THIS WAS LESS EVIDENT IN RAT LIVERS IN VIVO EXCEPT UNDER CHRONIC TREATMENT. IT IS CONCLUDED FOR THE FIRST TIME THAT HISTONE ACETYLATION PLAYS A ROLE IN THE MODULATION OF PNPLA3 LEVELS IN THE LIVER EXPOSED TO BINGE ETHANOL BOTH IN VITRO AND IN VIVO. 2017 13 3240 49 HEPATIC LIPID ACCUMULATION ALTERS GLOBAL HISTONE H3 LYSINE 9 AND 4 TRIMETHYLATION IN THE PEROXISOME PROLIFERATOR-ACTIVATED RECEPTOR ALPHA NETWORK. RECENT DATA SUGGEST THAT THE ETIOLOGY OF SEVERAL METABOLIC DISEASES IS CLOSELY ASSOCIATED WITH TRANSCRIPTOME ALTERATION BY ABERRANT HISTONE METHYLATION. WE PERFORMED DNA MICROARRAY AND CHIP-ON-CHIP ANALYSES TO EXAMINE TRANSCRIPTOME PROFILING AND TRIMETHYLATION ALTERATIONS TO IDENTIFY THE GENOMIC SIGNATURE OF NONALCOHOLIC FATTY LIVER DISEASE (NAFLD), THE MOST COMMON FORM OF CHRONIC LIVER DISEASE. TRANSCRIPTOME ANALYSIS SHOWED THAT STEATOTIC LIVERS IN HIGH-FAT DIET-FED APOLIPOPROTEIN E2 MICE SIGNIFICANTLY ALTERED THE EXPRESSION OF APPROXIMATELY 70% OF TOTAL GENES COMPARED WITH NORMAL DIET-FED CONTROL LIVERS, SUGGESTING THAT HEPATIC LIPID ACCUMULATION INDUCES DRAMATIC ALTERATIONS IN GENE EXPRESSION IN VIVO. ALSO, PATHWAY ANALYSIS SUGGESTED THAT GENES ENCODING CHROMATIN-REMODELING ENZYMES, SUCH AS JUMONJI C-DOMAIN-CONTAINING HISTONE DEMETHYLASES THAT REGULATE HISTONE H3K9 AND H3K4 TRIMETHYLATION (H3K9ME3, H3K4ME3), WERE SIGNIFICANTLY ALTERED IN STEATOTIC LIVERS. THUS, WE FURTHER INVESTIGATED THE GLOBAL H3K9ME3 AND H3K4ME3 STATUS IN LIPID-ACCUMULATED MOUSE PRIMARY HEPATOCYTES BY CHIP-ON-CHIP ANALYSIS. RESULTS SHOWED THAT HEPATIC LIPID ACCUMULATION INDUCED ABERRANT H3K9ME3 AND H3K4ME3 STATUS IN PEROXISOME PROLIFERATOR-ACTIVATED RECEPTOR ALPHA AND HEPATIC LIPID CATABOLISM NETWORK GENES, REDUCING THEIR MRNA EXPRESSION COMPARED WITH NON-TREATED CONTROL HEPATOCYTES. THIS STUDY PROVIDES THE FIRST EVIDENCE THAT EPIGENETIC REGULATION BY H3K9ME3 AND H3K4ME3 IN HEPATOCYTES MAY BE INVOLVED IN HEPATIC STEATOSIS AND THE PATHOGENESIS OF NAFLD. THUS, CONTROL OF H3K9ME3 AND H3K4ME3 REPRESENTS A POTENTIAL NOVEL NAFLD PREVENTION AND TREATMENT STRATEGY. 2012 14 3935 46 LIVER-SPECIFIC KNOCKDOWN OF CLASS IIA HDACS HAS LIMITED EFFICACY ON GLUCOSE METABOLISM BUT ENTAILS SEVERE ORGAN SIDE EFFECTS IN MICE. HISTONE DEACETYLASES (HDACS) ARE IMPORTANT REGULATORS OF EPIGENETIC GENE MODIFICATION THAT ARE INVOLVED IN THE TRANSCRIPTIONAL CONTROL OF METABOLISM. IN PARTICULAR CLASS IIA HDACS HAVE BEEN SHOWN TO AFFECT HEPATIC GLUCONEOGENESIS AND PREVIOUS APPROACHES REVEALED THAT THEIR INHIBITION REDUCES BLOOD GLUCOSE IN TYPE 2 DIABETIC MICE. IN THE PRESENT STUDY, WE AIMED TO EVALUATE THE POTENTIAL OF CLASS IIA HDAC INHIBITION AS A THERAPEUTIC OPPORTUNITY FOR THE TREATMENT +OF METABOLIC DISEASES. FOR THAT, SIRNAS SELECTIVELY TARGETING HDAC4, 5 AND 7 WERE SELECTED AND USED TO ACHIEVE A COMBINATORIAL KNOCKDOWN OF THESE THREE CLASS IIA HDAC ISOFORMS. SUBSEQUENTLY, THE HEPATOCELLULAR EFFECTS AS WELL AS THE IMPACT ON GLUCOSE AND LIPID METABOLISM WERE ANALYZED IN VITRO AND IN VIVO. THE TRIPLE KNOCKDOWN RESULTED IN A STATISTICALLY SIGNIFICANT DECREASE OF GLUCONEOGENIC GENE EXPRESSION IN MURINE AND HUMAN HEPATOCYTE CELL MODELS. A SIMILAR HDAC-INDUCED DOWNREGULATION OF HEPATIC GLUCONEOGENESIS GENES COULD BE ACHIEVED IN MICE USING A LIVER-SPECIFIC LIPID NANOPARTICLE SIRNA FORMULATION. HOWEVER, THE EFFICACY ON WHOLE BODY GLUCOSE METABOLISM ASSESSED BY PYRUVATE-TOLERANCE TESTS WERE ONLY LIMITED AND DID NOT OUTWEIGH THE SAFETY FINDINGS OBSERVED BY HISTOPATHOLOGICAL ANALYSIS IN SPLEEN AND KIDNEY. MECHANISTICALLY, AFFYMETRIX GENE EXPRESSION STUDIES PROVIDE EVIDENCE THAT CLASS IIA HDACS DIRECTLY TARGET OTHER KEY FACTORS BEYOND THE DESCRIBED FORKHEAD BOX (FOXP) TRANSCRIPTION REGULATORS, SUCH AS HEPATOCYTE NUCLEAR FACTOR 4 ALPHA (HNF4A). DOWNSTREAM OF THESE FACTORS SEVERAL ADDITIONAL PATHWAYS WERE REGULATED NOT MERELY INCLUDING GLUCOSE AND LIPID METABOLISM AND TRANSPORT. IN CONCLUSION, THE LIVER-DIRECTED COMBINATORIAL KNOCKDOWN OF HDAC4, 5 AND 7 BY THERAPEUTIC SIRNAS AFFECTED MULTIPLE PATHWAYS IN VITRO, LEADING IN VIVO TO THE DOWNREGULATION OF GENES INVOLVED IN GLUCONEOGENESIS. HOWEVER, THE EFFECTS ON GENE EXPRESSION LEVEL WERE NOT PARALLELED BY A SIGNIFICANT REDUCTION OF GLUCONEOGENESIS IN MICE. COMBINED KNOCKDOWN OF HDAC ISOFORMS WAS ASSOCIATED WITH SEVERE ADVERSE EFFECTS IN VIVO, CHALLENGING THIS APPROACH AS A TREATMENT OPTION FOR CHRONIC METABOLIC DISORDERS LIKE TYPE 2 DIABETES. 2020 15 3836 36 IONIZING RADIATION POTENTIATES HIGH-FAT DIET-INDUCED INSULIN RESISTANCE AND REPROGRAMS SKELETAL MUSCLE AND ADIPOSE PROGENITOR CELLS. EXPOSURE TO IONIZING RADIATION INCREASES THE RISK OF CHRONIC METABOLIC DISORDERS SUCH AS INSULIN RESISTANCE AND TYPE 2 DIABETES LATER IN LIFE. WE HYPOTHESIZED THAT IRRADIATION REPROGRAMS THE EPIGENOME OF METABOLIC PROGENITOR CELLS, WHICH COULD ACCOUNT FOR IMPAIRED METABOLISM AFTER CANCER TREATMENT. C57BL/6 MICE WERE TREATED WITH A SINGLE DOSE OF IRRADIATION AND SUBJECTED TO HIGH-FAT DIET (HFD). RNA SEQUENCING AND REDUCED REPRESENTATION BISULFITE SEQUENCING WERE USED TO CREATE TRANSCRIPTOMIC AND EPIGENOMIC PROFILES OF PREADIPOCYTES AND SKELETAL MUSCLE SATELLITE CELLS COLLECTED FROM IRRADIATED MICE. MICE SUBJECTED TO TOTAL BODY IRRADIATION SHOWED ALTERATIONS IN GLUCOSE METABOLISM AND, WHEN CHALLENGED WITH HFD, MARKED HYPERINSULINEMIA. INSULIN SIGNALING WAS CHRONICALLY DISRUPTED IN SKELETAL MUSCLE AND ADIPOSE PROGENITOR CELLS COLLECTED FROM IRRADIATED MICE AND DIFFERENTIATED IN CULTURE. EPIGENOMIC PROFILING OF SKELETAL MUSCLE AND ADIPOSE PROGENITOR CELLS FROM IRRADIATED ANIMALS REVEALED SUBSTANTIAL DNA METHYLATION CHANGES, NOTABLY FOR GENES REGULATING THE CELL CYCLE, GLUCOSE/LIPID METABOLISM, AND EXPRESSION OF EPIGENETIC MODIFIERS. OUR RESULTS SHOW THAT TOTAL BODY IRRADIATION ALTERS INTRACELLULAR SIGNALING AND EPIGENETIC PATHWAYS REGULATING CELL PROLIFERATION AND DIFFERENTIATION OF SKELETAL MUSCLE AND ADIPOSE PROGENITOR CELLS AND PROVIDE A POSSIBLE MECHANISM BY WHICH IRRADIATION USED IN CANCER TREATMENT INCREASES THE RISK FOR METABOLIC DISEASE LATER IN LIFE. 2016 16 2590 41 EPIGENETICS OF PROTEASOME INHIBITION IN THE LIVER OF RATS FED ETHANOL CHRONICALLY. AIM: TO EXAMINE THE EFFECTS OF ETHANOL-INDUCED PROTEASOME INHIBITION, AND THE EFFECTS OF PROTEASOME INHIBITION IN THE REGULATION OF EPIGENETIC MECHANISMS. METHODS: RATS WERE FED ETHANOL FOR 1 MO USING THE TSUKAMOTO-FRENCH MODEL AND WERE COMPARED TO RATS GIVEN THE PROTEASOME INHIBITOR PS-341 (BORTEZOMIB, VELCADE(TM)) BY INTRAPERITONEAL INJECTION. MICROARRAY ANALYSIS AND REAL TIME PCR WERE PERFORMED AND PROTEASOME ACTIVITY ASSAYS AND WESTERN BLOT ANALYSIS WERE PERFORMED USING ISOLATED NUCLEI. RESULTS: CHRONIC ETHANOL FEEDING CAUSED A SIGNIFICANT INHIBITION OF THE UBIQUITIN PROTEASOME PATHWAY IN THE NUCLEUS, WHICH LED TO CHANGES IN THE TURNOVER OF TRANSCRIPTIONAL FACTORS, HISTONE-MODIFYING ENZYMES, AND, THEREFORE, AFFECTED EPIGENETIC MECHANISMS. CHRONIC ETHANOL FEEDING WAS RELATED TO AN INCREASE IN HISTONE ACETYLATION, AND IT IS HYPOTHESIZED THAT THE PROTEASOME PROTEOLYTIC ACTIVITY REGULATED HISTONE MODIFICATIONS BY CONTROLLING THE STABILITY OF HISTONE MODIFYING ENZYMES, AND, THEREFORE, REGULATED THE CHROMATIN STRUCTURE, ALLOWING EASY ACCESS TO CHROMATIN BY RNA POLYMERASE, AND, THUS, PROPER GENE EXPRESSION. PROTEASOME INHIBITION BY PS-341 INCREASED HISTONE ACETYLATION SIMILAR TO CHRONIC ETHANOL FEEDING. IN ADDITION, PROTEASOME INHIBITION CAUSED DRAMATIC CHANGES IN HEPATIC REMETHYLATION REACTIONS AS THERE WAS A SIGNIFICANT DECREASE IN THE ENZYMES RESPONSIBLE FOR THE REGENERATION OF S-ADENOSYLMETHIONINE, AND, IN PARTICULAR, A SIGNIFICANT DECREASE IN THE BETAINE-HOMOCYSTEINE METHYLTRANSFERASE ENZYME. THIS SUGGESTED THAT HYPOMETHYLATION WAS ASSOCIATED WITH PROTEASOME INHIBITION, AS INDICATED BY THE DECREASE IN HISTONE METHYLATION. CONCLUSION: THE ROLE OF PROTEASOME INHIBITION IN REGULATING EPIGENETIC MECHANISMS, AND ITS LINK TO LIVER INJURY IN ALCOHOLIC LIVER DISEASE, IS THUS A PROMISING APPROACH TO STUDY LIVER INJURY DUE TO CHRONIC ETHANOL CONSUMPTION. 2009 17 6092 41 THE EFFECTS OF EPIGENETIC MODIFICATION ON THE OCCURRENCE AND PROGRESSION OF LIVER DISEASES AND THE INVOLVED MECHANISM. INTRODUCTION: EPIGENETIC MODIFICATION IS A TYPE OF GENE EXPRESSION AND REGULATION THAT DOES NOT INVOLVE CHANGES IN DNA SEQUENCES. AN INCREASING NUMBER OF STUDIES HAVE PROVEN THAT EPIGENETIC MODIFICATIONS PLAY AN IMPORTANT ROLE IN THE OCCURRENCE AND PROGRESSION OF LIVER DISEASES THROUGH THE GENE REGULATION AND PROTEIN EXPRESSIONS OF HEPATOCELLULAR LIPID METABOLISM, INFLAMMATORY REACTION, CELL PROLIFERATION, AND ACTIVATION, ETC.AREAS COVERED: IN THIS STUDY, WE ELABORATED AND ANALYZED THE UNDERLYING FUNCTIONAL MECHANISM OF EPIGENETIC MODIFICATION IN ALCOHOLIC LIVER DISEASE (ALD), NONALCOHOLIC FATTY LIVER DISEASE (NAFLD), LIVER FIBROSIS (LF), VIRAL HEPATITIS, HEPATOCELLULAR CARCINOMA (HCC), AND RESEARCH PROGRESS OF RECENT YEARS.EXPERT OPINION: THE FURTHER UNDERSTANDING OF EPIGENETIC MECHANISMS THAT CAN REGULATE GENE EXPRESSION AND CELL PHENOTYPE LEADS TO NEW INSIGHTS IN EPIGENETIC CONTROL OF CHRONIC LIVER DISEASE. CURRENTLY, HEPATOLOGISTS ARE EXPLORING THE ROLE OF DNA METHYLATION, HISTONE/CHROMATIN MODIFICATION, AND NON-CODING RNA IN SPECIFIC LIVER PATHOLOGY. THESE FINDINGS HAVE LED TO ADVANCES IN DIRECT EPIGENETIC BIOMARKER TESTING OF PATIENT TISSUE OR BODY FLUID SPECIMENS, AS WELL AS QUANTITATIVE ANALYSIS. BASED ON THESE FINDINGS, DRUG VALIDATION OF SOME TARGETS INVOLVED IN THE EPIGENETIC MECHANISM OF LIVER DISEASE IS GRADUALLY BEING CARRIED OUT CLINICALLY. 2020 18 420 45 ANDROGEN-MEDIATED PERTURBATION OF THE HEPATIC CIRCADIAN SYSTEM THROUGH EPIGENETIC MODULATION PROMOTES NAFLD IN PCOS MICE. IN WOMEN, EXCESS ANDROGEN CAUSES POLYCYSTIC OVARY SYNDROME (PCOS), A COMMON FERTILITY DISORDER WITH COMORBID METABOLIC DYSFUNCTIONS INCLUDING DIABETES, OBESITY, AND NONALCOHOLIC FATTY LIVER DISEASE. USING A PCOS MOUSE MODEL, THIS STUDY SHOWS THAT CHRONIC HIGH ANDROGEN LEVELS CAUSE HEPATIC STEATOSIS WHILE HEPATOCYTE-SPECIFIC ANDROGEN RECEPTOR (AR)-KNOCKOUT RESCUES THIS PHENOTYPE. MOREOVER, THROUGH RNA-SEQUENCING AND METABOLOMIC STUDIES, WE HAVE IDENTIFIED KEY METABOLIC GENES AND PATHWAYS AFFECTED BY HYPERANDROGENISM. OUR STUDIES REVEAL THAT A LARGE NUMBER OF METABOLIC GENES ARE DIRECTLY REGULATED BY ANDROGENS THROUGH AR BINDING TO ANDROGEN RESPONSE ELEMENT SEQUENCES ON THE PROMOTER REGION OF THESE GENES. INTERESTINGLY, A NUMBER OF CIRCADIAN GENES ARE ALSO DIFFERENTIALLY REGULATED BY ANDROGENS. IN VIVO AND IN VITRO STUDIES USING A CIRCADIAN REPORTER [PERIOD2::LUCIFERASE (PER2::LUC)] MOUSE MODEL DEMONSTRATE THAT ANDROGENS CAN DIRECTLY DISRUPT THE HEPATIC TIMING SYSTEM, WHICH IS A KEY REGULATOR OF LIVER METABOLISM. CONSEQUENTLY, STUDIES SHOW THAT ANDROGENS DECREASE H3K27ME3, A GENE SILENCING MARK ON THE PROMOTER OF CORE CLOCK GENES, BY INHIBITING THE EXPRESSION OF HISTONE METHYLTRANSFERASE, EZH2, WHILE INDUCING THE EXPRESSION OF THE HISTONE DEMETHYLASE, JMJD3, WHICH IS RESPONSIBLE FOR ADDING AND REMOVING THE H3K27ME3 MARK, RESPECTIVELY. FINALLY, WE REPORT THAT UNDER HYPERANDROGENIC CONDITIONS, SOME OF THE SAME CIRCADIAN/METABOLIC GENES THAT ARE UPREGULATED IN THE MOUSE LIVER ARE ALSO ELEVATED IN NONHUMAN PRIMATE LIVERS. IN SUMMARY, THESE STUDIES NOT ONLY PROVIDE AN OVERALL UNDERSTANDING OF HOW HYPERANDROGENISM ASSOCIATED WITH PCOS AFFECTS LIVER GENE EXPRESSION AND METABOLISM BUT ALSO OFFER INSIGHT INTO THE UNDERLYING MECHANISMS LEADING TO HEPATIC STEATOSIS IN PCOS. 2022 19 318 35 ALCOHOL-INDUCED EPIGENETIC CHANGES IN CANCER. CHRONIC, HEAVY ALCOHOL CONSUMPTION IS ASSOCIATED WITH SERIOUS NEGATIVE HEALTH EFFECTS, INCLUDING THE DEVELOPMENT OF SEVERAL CANCER TYPES. ONE OF THE PATHWAYS AFFECTED BY ALCOHOL TOXICITY IS THE ONE-CARBON METABOLISM. THE ALCOHOL-INDUCED IMPAIRMENT OF THIS METABOLIC PATHWAY RESULTS IN EPIGENETIC CHANGES ASSOCIATED WITH CANCER DEVELOPMENT. THESE EPIGENETIC CHANGES ARE INDUCED BY FOLATE DEFICIENCY AND BY PRODUCTS OF THE ETHANOL METABOLISM. THE CHANGES INDUCED BY LONG-TERM HEAVY ETHANOL CONSUMPTION RESULT IN ELEVATIONS OF HOMOCYSTEINE AND S-ADENOSYL-HOMOCYSTEINE (SAH) AND REDUCTIONS IN S-ADENOSYLMETHIONINE (SAM) AND ANTIOXIDANT GLUTATHIONE (GSH) LEVELS, LEADING TO ABNORMAL PROMOTER GENE HYPERMETHYLATION, GLOBAL HYPOMETHYLATION, AND METABOLIC INSUFFICIENCY OF ANTIOXIDANT DEFENSE MECHANISMS. IN ADDITION, REACTIVE OXYGEN SPECIES (ROS) GENERATED DURING THE ETHANOL METABOLISM INDUCE ALTERATIONS IN DNA METHYLATION PATTERNS THAT PLAY A CRITICAL ROLE IN CANCER DEVELOPMENT. SPECIFIC EPIGENETIC CHANGES IN ESOPHAGEAL, HEPATIC, AND COLORECTAL CANCERS HAVE BEEN DETECTED IN BLOOD SAMPLES AND PROPOSED TO BE USED CLINICALLY AS EPIGENETIC BIOMARKERS FOR DIAGNOSIS AND PROGNOSIS OF THESE CANCERS. ALSO, GENETIC VARIANTS OF GENES INVOLVED IN ONE-CARBON METABOLISM AND ETHANOL METABOLISM WERE FOUND TO MODULATE THE RELATIONSHIP BETWEEN ALCOHOL-INDUCED EPIGENETIC CHANGES AND CANCER RISK. FURTHERMORE, ALCOHOL METABOLISM PRODUCTS HAVE BEEN ASSOCIATED WITH AN INCREASE IN NADH LEVELS, WHICH LEAD TO HISTONE MODIFICATIONS AND CHANGES IN GENE EXPRESSION THAT IN TURN INFLUENCE CANCER SUSCEPTIBILITY. CHRONIC EXCESSIVE USE OF ALCOHOL ALSO AFFECTS SELECTED MEMBERS OF THE FAMILY OF MICRORNAS, AND AS MIRNAS COULD ACT AS EPIGENETIC REGULATORS, THIS MAY PLAY AN IMPORTANT ROLE IN CARCINOGENESIS. IN CONCLUSION, TARGETING ALCOHOL-INDUCED EPIGENETIC CHANGES IN SEVERAL CANCER TYPES COULD MAKE AVAILABLE CLINICAL TOOLS FOR THE DIAGNOSIS, PROGNOSIS, AND TREATMENT OF THESE CANCERS, WITH AN IMPORTANT ROLE IN PRECISION MEDICINE. 2018 20 457 39 APPLYING A MULTISCALE SYSTEMS BIOLOGY APPROACH TO STUDY THE EFFECT OF CHRONIC LOW-DOSE EXPOSURE TO URANIUM IN RAT KIDNEYS. PURPOSE: TO EXAMINE THE EFFECTS OF LOW-DOSE EXPOSURE TO URANIUM WITH A SYSTEMS BIOLOGY APPROACH, A MULTISCALE HIGH-THROUGHPUT MULTI-OMICS ANALYSIS WAS APPLIED WITH A PROTOCOL FOR CHRONIC EXPOSURE TO THE RAT KIDNEY. METHODS: MALE AND FEMALE RATS WERE CONTAMINATED FOR NINE MONTHS THROUGH THEIR DRINKING WATER WITH A NONTOXIC SOLUTION OF URANYL NITRATE. A MULTISCALE APPROACH ENABLED CLINICAL MONITORING ASSOCIATED WITH METABOLOMIC AND TRANSCRIPTOMIC (MRNA AND MICRORNA) ANALYSES. RESULTS: A SEX-INTERACTION EFFECT WAS OBSERVED IN THE KIDNEY, URINE, AND PLASMA METABOLOMES OF CONTAMINATED RATS. MOREOVER, URINE AND KIDNEY METABOLIC PROFILES CORRELATED AND CONFIRMED THAT THE PRIMARY DYSREGULATED METABOLISMS ARE THOSE OF NICOTINATE-NICOTINAMIDE AND OF UNSATURATED FATTY ACID BIOSYNTHESIS. UPSTREAM OF THE METABOLIC PATHWAYS, TRANSCRIPTOMIC PROFILES OF THE KIDNEY REVEAL GENE ACTIVITY FOCUSED ON GENE REGULATION MECHANISMS, CELL SIGNALING, CELL STRUCTURE, DEVELOPMENTAL PROCESSES, AND CELL PROLIFERATION. EXAMINATION OF EPIGENETIC POST-TRANSCRIPTIONAL GENE REGULATION PROCESSES SHOWED SIGNIFICANT DYSREGULATION OF 70 MICRO-RNAS. THE MULTI-OMICS APPROACH HIGHLIGHTED THE ACTIVITIES OF THE CELLS' BIOLOGICAL PROCESSES ON MULTIPLE SCALES THROUGH ANALYSIS OF GENE EXPRESSION, CONFIRMED BY CHANGES OBSERVED IN THE METABOLOME. CONCLUSION: OUR RESULTS SHOWED CHANGES IN MULTI-OMIC PROFILES OF RATS EXPOSED TO LOW DOSES OF URANIUM CONTAMINATION, COMPARED WITH CONTROLS. THESE CHANGES INVOLVED GENE EXPRESSION AS WELL AS MODIFICATIONS IN THE TRANSCRIPTOME AND THE METABOLOME. THE METABOLOMIC PROFILE CONFIRMED THAT THE MAIN MOLECULAR TARGETS OF URANIUM IN KIDNEY CELLS ARE THE METABOLISM OF NICOTINATE-NICOTINAMIDE AND THE BIOSYNTHESIS OF UNSATURATED FATTY ACIDS. ADDITIONALLY, GENE EXPRESSION ANALYSIS SHOWED THAT THE METABOLISM OF FATTY ACIDS IS TARGETED BY PROCESSES ASSOCIATED WITH CELL FUNCTION. THESE RESULTS DEMONSTRATE THAT MULTISCALE SYSTEMS BIOLOGY IS USEFUL IN ELUCIDATING THE MOST DISCRIMINATIVE PATHWAYS FROM GENOMIC TO METABOLOMIC LEVELS FOR ASSESSING THE BIOLOGICAL IMPACT OF THIS LOW-LEVEL ENVIRONMENTAL EXPOSURE, I.E. THE EXPOSOME. 2019