1 413 147 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 2 6092 43 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 3 6900 46 [THE DIAGNOSTIC IMPORTANCE OF CIRCULATING MICRORNA FOR NON-ALCOHOLIC FATTY LIVER DISEASE (REVIEW OF LITERATURE).]. NON-ALCOHOLIC FATTY LIVER DISEASE (NAFLD) IS ONE OF THE LEADING CAUSES OF CHRONIC LIVER DISEASES IN THE WORLD. THE BIOPSY IS REQUIRED TO CONFIRM THE DIAGNOSIS BUT DUE TO ITS INVASIVENESS, THIS PROCEDURE IS NOT SUITABLE FOR THE MASSIVE SCREENING. THERE ARE LABORATORY CRITERIA OF PRIMARY MEDICAL EXAMINATION OF THE PATIENTS WHO ARE SUSPECTED TO HAVE NAFLD THAT ALLOW DIAGNOSING THE PATHOLOGICAL PROCESS, BUT THESE CRITERIA DO NOT COMPLY WITH CLINICIANS' REQUIREMENTS. AT THE SAME TIME, IT IS CRUCIAL TO IDENTIFY THE PATIENTS IN THE INITIAL STAGES OF NAFLD. RECENTLY, THE ATTENTION OF THE SCIENTISTS WAS CONCENTRATED ON THE RESEARCH OF THE MECHANISM OF NAFLD DEVELOPMENT AND NEW DIAGNOSTIC APPROACHES. ACCUMULATING RESULTS OF THIS RESEARCH SHOW THAT NAFLD DEVELOPMENT IS REGULATED WITH EPIGENETIC FACTORS, INCLUDING MICRORNAS FAMILY (MICRORNA, MIR), THAT MAY HAVE HIGH DIAGNOSTIC AND PROGNOSTIC VALUE. IN THIS REVIEW, DATA EXTRACTED FROM PUBMED ARE USED TO DISCUSS THE POTENTIAL ROLE OF MICRORNA IN THE LIVER LIPID METABOLISM AND FATTY LIVER DISEASE. THE POSSIBILITIES OF MICRO RNA (MIR-16, MIR-21, MIR-34A, MIR-103, MIR-122, MIR-145, MIR-192, AND OTHERS) USE AS PROSPECTIVE BIOMARKERS FOR LOW-INVASIVE NAFLD DIAGNOSTIC, EVALUATION OF STEATOSIS ACTIVITY AND FIBROSIS SCORE AND STAGES, AND PROGNOSTIC MARKERS OF THE DISEASE ARE REVIEWED. THIS RESEARCH DISCUSSES THE ANALYTICAL CHARACTERISTICS, BENEFITS AND POSSIBLE LIMITATIONS OF THEIR USE IN THE CLINICAL PRACTICE. THE PRELIMINARY DATA ALLOW CLAIMING THAT SOME MICRORNAS ARE EXTREMELY PERSPECTIVE LOW-INVASIVE DIAGNOSTIC INSTRUMENT AND FURTHER RESEARCH IS REQUIRED TO INVESTIGATE THE IMPACT OF CERTAIN MICRORNAS IN THE PATHOGENETIC MECHANISM OF NAFLD DEVELOPMENT. 2019 4 4369 35 MIRNAS AND NAFLD: FROM PATHOPHYSIOLOGY TO THERAPY. NON-ALCOHOLIC FATTY LIVER DISEASE (NAFLD) IS ASSOCIATED WITH A THOROUGH REPROGRAMMING OF HEPATIC METABOLISM. EPIGENETIC MECHANISMS, IN PARTICULAR THOSE ASSOCIATED WITH DEREGULATION OF THE EXPRESSIONS AND ACTIVITIES OF MICRORNAS (MIRNAS), PLAY A MAJOR ROLE IN METABOLIC DISORDERS ASSOCIATED WITH NAFLD AND THEIR PROGRESSION TOWARDS MORE SEVERE STAGES OF THE DISEASE. IN THIS REVIEW, WE DISCUSS THE RECENT PROGRESS ADDRESSING THE ROLE OF THE MANY FACETS OF COMPLEX MIRNA REGULATORY NETWORKS IN THE DEVELOPMENT AND PROGRESSION OF NAFLD. THE BASIC CONCEPTS AND MECHANISMS OF MIRNA-MEDIATED GENE REGULATION AS WELL AS THE VARIOUS SETBACKS ENCOUNTERED IN BASIC AND TRANSLATIONAL RESEARCH IN THIS FIELD ARE DEBATED. MIRNAS IDENTIFIED SO FAR, WHOSE EXPRESSIONS/ACTIVITIES ARE DEREGULATED IN NAFLD, AND WHICH CONTRIBUTE TO THE OUTCOMES OF THIS PATHOLOGY ARE FURTHER REVIEWED. FINALLY, THE POTENTIAL THERAPEUTIC USAGES IN A SHORT TO MEDIUM TERM OF MIRNA-BASED STRATEGIES IN NAFLD, IN PARTICULAR TO IDENTIFY NON-INVASIVE BIOMARKERS, OR TO DESIGN PHARMACOLOGICAL ANALOGUES/INHIBITORS HAVING A BROAD RANGE OF ACTIONS ON HEPATIC METABOLISM, ARE HIGHLIGHTED. 2019 5 1128 43 COMPREHENSIVE ANALYSIS OF EPIGENETIC AND EPITRANSCRIPTOMIC GENES' EXPRESSION IN HUMAN NAFLD. NON-ALCOHOLIC FATTY LIVER DISEASE (NAFLD) IS A MULTIFACTORIAL CONDITION WITH A COMPLEX ETIOLOGY. ITS INCIDENCE IS INCREASING GLOBALLY IN PARALLEL WITH THE OBESITY EPIDEMIC, AND IT IS NOW CONSIDERED THE MOST COMMON LIVER DISEASE IN WESTERN COUNTRIES. THE PRECISE MECHANISMS UNDERLYING THE DEVELOPMENT AND PROGRESSION OF NAFLD ARE COMPLEX AND STILL POORLY UNDERSTOOD. THE DYSREGULATION OF EPIGENETIC AND EPITRANSCRIPTOMIC MECHANISMS IS INCREASINGLY RECOGNIZED TO PLAY PATHOGENIC ROLES IN MULTIPLE CONDITIONS, INCLUDING CHRONIC LIVER DISEASES. HERE, WE HAVE PERFORMED A COMPREHENSIVE ANALYSIS OF THE EXPRESSION OF EPIGENETIC AND EPITRANSCRIPTOMIC GENES IN A TOTAL OF 903 LIVER TISSUE SAMPLES CORRESPONDING TO PATIENTS WITH NORMAL LIVER, OBESE PATIENTS, AND PATIENTS WITH NON-ALCOHOLIC FATTY LIVER (NAFL) AND NON-ALCOHOLIC STEATOHEPATITIS (NASH), ADVANCING STAGES IN NAFLD PROGRESSION. WE INTEGRATED TEN TRANSCRIPTOMIC DATASETS IN AN UNBIASED MANNER, ENABLING THEIR ROBUST ANALYSIS AND COMPARISON. WE DESCRIBE THE COMPLETE LANDSCAPE OF EPIGENETIC AND EPITRANSCRIPTOMIC GENES' EXPRESSION ALONG THE COURSE OF THE DISEASE. WE IDENTIFY SIGNATURES OF GENES SIGNIFICANTLY DYSREGULATED IN ASSOCIATION WITH DISEASE PROGRESSION, PARTICULARLY WITH LIVER FIBROSIS DEVELOPMENT. MOST OF THESE EPIGENETIC AND EPITRANSCRIPTOMIC EFFECTORS HAVE NOT BEEN PREVIOUSLY DESCRIBED IN HUMAN NAFLD, AND THEIR ALTERED EXPRESSION MAY HAVE PATHOGENIC IMPLICATIONS. WE ALSO PERFORMED A COMPREHENSIVE ANALYSIS OF THE EXPRESSION OF ENZYMES INVOLVED IN THE METABOLISM OF THE SUBSTRATES AND COFACTORS OF EPIGENETIC AND EPITRANSCRIPTOMIC EFFECTORS. THIS STUDY PROVIDES NOVEL INFORMATION ON NAFLD PATHOGENESIS AND MAY ALSO GUIDE THE IDENTIFICATION OF DRUG TARGETS TO TREAT THIS CONDITION AND ITS PROGRESSION TOWARDS HEPATOCELLULAR CARCINOMA. 2023 6 4286 47 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 7 1285 39 DECIPHERING THE ROLE OF ABERRANT DNA METHYLATION IN NAFLD AND NASH. THE GLOBAL INCIDENCE OF NONALCOHOLIC FATTY LIVER DISEASE (NAFLD) IS MOUNTING INCESSANTLY, AND IT IS EMERGING AS THE MOST FREQUENT CAUSE OF CHRONIC AND END STAGE LIVER DISORDERS. IT IS THE STARTING POINT FOR A RANGE OF CONDITIONS FROM SIMPLE STEATOSIS TO MORE PROGRESSIVE NONALCOHOLIC STEATOHEPATITIS (NASH) AND ASSOCIATED HEPATOCELLULAR CARCINOMA (HCC). DYSREGULATION OF INSULIN SECRETION AND DYSLIPIDEMIA DUE TO OBESITY AND OTHER LIFESTYLE VARIABLES ARE THE PRIMARY CONTRIBUTORS TO ESTABLISHMENT OF NAFLD. ONSET AND PROGRESSION OF NAFLD IS ORCHESTRATED BY AN INTERPLAY OF METABOLIC ENVIRONMENT WITH GENETIC AND EPIGENETIC FACTORS. AN INCOMPLETELY UNDERSTOOD MECHANISM OF NAFLD PROGRESSION HAS GREATLY HAMPERED THE PROGRESS IN IDENTIFICATION OF NOVEL PROGNOSTIC AND THERAPEUTIC STRATEGIES. EMERGING EVIDENCE SUGGESTS ALTERED DNA METHYLATION PATTERN AS A KEY DETERMINANT OF NAFLD PATHOGENESIS. ENVIRONMENTAL AND LIFESTYLE FACTORS CAN MANIPULATE DNA METHYLATION PATTERNS IN A REVERSIBLE MANNER, WHICH MANIFESTS AS CHANGES IN GENE EXPRESSION. IN THIS REVIEW WE ATTEMPT TO HIGHLIGHT THE IMPORTANCE OF DNA METHYLATION IN ESTABLISHMENT AND PROGRESSION OF NAFLD. DEVELOPMENT OF NOVEL DIAGNOSTIC, PROGNOSTIC AND THERAPEUTIC STRATEGIES CENTERED AROUND DNA METHYLATION SIGNATURES AND MODIFIERS HAS ALSO BEEN EXPLORED. 2022 8 5890 42 SYSTEMS BIOLOGY ELUCIDATES COMMON PATHOGENIC MECHANISMS BETWEEN NONALCOHOLIC AND ALCOHOLIC-FATTY LIVER DISEASE. THE ABNORMAL ACCUMULATION OF FAT IN THE LIVER IS OFTEN RELATED EITHER TO METABOLIC RISK FACTORS ASSOCIATED WITH METABOLIC SYNDROME IN THE ABSENCE OF ALCOHOL CONSUMPTION (NONALCOHOLIC FATTY LIVER DISEASE, NAFLD) OR TO CHRONIC ALCOHOL CONSUMPTION (ALCOHOLIC FATTY LIVER DISEASE, AFLD). CLINICAL AND HISTOLOGICAL STUDIES SUGGEST THAT NAFLD AND AFLD SHARE PATHOGENIC MECHANISMS. NEVERTHELESS, CURRENT DATA ARE STILL INCONCLUSIVE AS TO WHETHER THE UNDERLYING BIOLOGICAL PROCESS AND DISEASE PATHWAYS OF NAFLD AND AFLD ARE ALIKE. OUR PRIMARY AIM WAS TO INTEGRATE OMICS AND PHYSIOLOGICAL DATA TO ANSWER THE QUESTION OF WHETHER NAFLD AND AFLD SHARE MOLECULAR PROCESSES THAT LEAD TO DISEASE DEVELOPMENT. WE ALSO EXPLORED THE EXTENT TO WHICH INSULIN RESISTANCE (IR) IS A DISTINCTIVE FEATURE OF NAFLD. TO ANSWER THESE QUESTIONS, WE USED SYSTEMS BIOLOGY APPROACHES, SUCH AS GENE ENRICHMENT ANALYSIS, PROTEIN-PROTEIN INTERACTION NETWORKS, AND GENE PRIORITIZATION, BASED ON MULTI-LEVEL DATA EXTRACTED BY COMPUTATIONAL DATA MINING. WE OBSERVED THAT THE LEADING DISEASE PATHWAYS ASSOCIATED WITH NAFLD DID NOT SIGNIFICANTLY DIFFER FROM THOSE OF AFLD. HOWEVER, SYSTEMS BIOLOGY REVEALED THE IMPORTANCE OF EACH MOLECULAR PROCESS BEHIND EACH OF THE TWO DISEASES, AND DISSECTED DISTINCTIVE MOLECULAR NAFLD AND AFLD-SIGNATURES. COMPARATIVE CO-ANALYSIS OF NAFLD AND AFLD CLARIFIED THE PARTICIPATION OF NAFLD, BUT NOT AFLD, IN CARDIOVASCULAR DISEASE, AND SHOWED THAT INSULIN SIGNALING IS IMPAIRED IN FATTY LIVER REGARDLESS OF THE NOXA, BUT THE PUTATIVE REGULATORY MECHANISMS ASSOCIATED WITH NAFLD SEEM TO ENCOMPASS A COMPLEX NETWORK OF GENES AND PROTEINS, PLAUSIBLE OF EPIGENETIC MODIFICATIONS. GENE PRIORITIZATION SHOWED A CANCER-RELATED FUNCTIONAL MAP THAT SUGGESTS THAT THE FATTY TRANSFORMATION OF THE LIVER TISSUE IS REGARDLESS OF THE CAUSE, AN EMERGING MECHANISM OF UBIQUITOUS ONCOGENIC ACTIVATION. IN CONCLUSION, SIMILAR UNDERLYING DISEASE MECHANISMS LEAD TO NAFLD AND AFLD, BUT SPECIFIC ONES DEPICT A PARTICULAR DISEASE SIGNATURE THAT HAS A DIFFERENT IMPACT ON THE SYSTEMIC CONTEXT. 2013 9 1131 37 COMPREHENSIVE CIRCULAR RNA EXPRESSION PROFILING WITH ASSOCIATED CERNA NETWORK REVEALS THEIR THERAPEUTIC POTENTIAL IN CHOLESTEATOMA. CHOLESTEATOMA IS A CHRONIC DISEASE THAT PATHOLOGICALLY DISPLAYS A BENIGN TUMOR WITH EXCESSIVE SQUAMOUS EPITHELIAL CELL PROLIFERATION IN THE MIDDLE EAR. CLINICALLY, HOWEVER, IT CAN MANIFEST MALIGNANT BEHAVIOR BY DESTROYING ADJACENT TISSUES AND ORGANS. ALTHOUGH PREVIOUS STUDIES HAVE DEMONSTRATED THAT THE PATHOGENESIS OF CHOLESTEATOMA IS CORRELATED WITH EPIGENETIC DYSREGULATION, THE EXACT MECHANISM REMAINS UNCLEAR. CIRCULAR RNAS (CIRCRNAS) HAVE BEEN REVEALED AS BEING ABUNDANTLY EXPRESSED IN VARIOUS ORGANISMS AND HAVE BEEN FOUND TO CONTRIBUTE TO THE REGULATION OF MANY DISEASES. TO DATE, NO REPORTS HAVE ELUCIDATED THEIR EXPRESSION PROFILES AND FUNCTIONS IN CHOLESTEATOMA. IN THE PRESENT STUDY, THE CIRCRNA EXPRESSION PROFILE IN CHOLESTEATOMA WAS EXPLORED FOR THE FIRST TIME BY USING MICROARRAY ANALYSIS. WE OBTAINED A TOTAL OF 355 SIGNIFICANTLY DIFFERENTIALLY EXPRESSED CIRCRNAS IN CHOLESTEATOMA, AMONG WHICH 101 WERE IDENTIFIED TO BE UPREGULATED AND 254 DOWNREGULATED. BY CONSTRUCTING CIRCRNA?LNCRNA?MIRNA?MRNA COMPETING ENDOGENOUS RNA (CERNA) NETWORK, IT WAS DISCOVERED THAT CIRCRNAS MAY FUNCTION AS CERNAS AND CONTRIBUTE TO THE FORMATION OF CHOLESTEATOMA. THESE RESULTS PROVIDE NOVEL INSIGHT INTO THE PATHOGENESIS OF CHOLESTEATOMA AND SUGGEST CIRCRNAS AS POTENTIAL PROMISING THERAPEUTIC TARGETS FOR CHOLESTEATOMA. 2020 10 1666 52 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 11 1348 32 DETERMINANTS OF FIBROSIS PROGRESSION AND REGRESSION IN NASH. CIRRHOSIS HAS BECOME THE MAJOR LIVER-RELATED CLINICAL ENDPOINT IN NON-ALCOHOLIC STEATOHEPATITIS (NASH). HOWEVER, PROGRESSION TO CIRRHOSIS IS LESS PREDICTABLE IN NASH THAN IN OTHER CHRONIC LIVER DISEASES. THIS IS DUE TO THE COMPLEX AND MULTIFACTORIAL AETIOLOGY OF NASH, WHICH IS DETERMINED BY LIFESTYLE AND NUTRITION, MULTIPLE GENETIC AND EPIGENETIC FACTORS, AND A PROMINENT ROLE OF HEPATIC AND EXTRAHEPATIC COMORBIDITIES. THUS, MODEST CHANGES IN THESE COFACTORS CAN ALSO INDUCE FIBROSIS REGRESSION, AT LEAST IN PATIENTS WITH PRECIRRHOTIC LIVER DISEASE. FIBROGENESIS IN NASH CORRELATES WITH, BUT IS INDIRECTLY COUPLED TO, CLASSICAL INFLAMMATION, SINCE FIBROSIS PROGRESSION IS DRIVEN BY REPETITIVE PERIODS OF REPAIR. WHILE HEPATOCYTE LIPOAPOPTOSIS IS A KEY DRIVING FORCE OF FIBROSIS PROGRESSION, ACTIVATED HEPATIC STELLATE CELLS, MYOFIBROBLASTS, CHOLANGIOCYTES, MACROPHAGES AND COMPONENTS OF THE PATHOLOGICAL EXTRACELLULAR MATRIX ARE MAJOR FIBROGENIC EFFECTORS AND THUS PHARMACOLOGICAL TARGETS FOR THERAPIES AIMED AT INHIBITION OF FIBROSIS PROGRESSION OR INDUCTION OF FIBROSIS REVERSAL. THE ADVENT OF NOVEL, HIGHLY SENSITIVE AND SPECIFIC SERUM BIOMARKERS AND IMAGING METHODS TO ASSESS THE DYNAMICS OF LIVER FIBROSIS IN NASH WILL IMPROVE DETECTION, STRATIFICATION AND FOLLOW-UP OF PATIENTS WITH PROGRESSIVE NASH . THESE NON-INVASIVE TOOLS WILL ALSO PROMOTE THE CLINICAL DEVELOPMENT OF ANTIFIBROTIC DRUGS, BY PERMITTING THE DESIGN OF LEAN PROOF-OF-CONCEPT STUDIES, AND ENABLING DEVELOPMENT OF A PERSONALISED ANTIFIBROTIC THERAPY FOR PATIENTS WITH RAPID FIBROSIS PROGRESSION OR ADVANCED DISEASE. 2018 12 5386 35 REDOX HOMEOSTASIS AND EPIGENETICS IN NON-ALCOHOLIC FATTY LIVER DISEASE (NAFLD). NON-ALCOHOLIC FATTY LIVER DISEASE (NAFLD), AN ACCUMULATION OF INTRA-HEPATIC TRIGLYCERIDES THAT IS OFTEN CONSIDERED THE HEPATIC MANIFESTATION OF INSULIN RESISTANCE, IS THE MOST COMMON CAUSE OF CHRONIC LIVER DISEASE IN THE WESTERN COUNTRIES WITH UP TO ONE THIRD OF THE POPULATION AFFECTED. NAFLD IS A SPECTRUM OF DISTURBANCES THAT ENCOMPASSES VARIOUS DEGREES OF LIVER DAMAGE RANGING FROM SIMPLE STEATOSIS TO NON-ALCOHOLIC STEATOHEPATITIS (NASH). NASH IS CHARACTERIZED BY HEPATOCELLULAR INJURY/INFLAMMATION WITH OR WITHOUT FIBROSIS. THE INDIVIDUALS WITH NAFLD DEVELOP NASH IN 10% OF THE CASES, AND ARE ALSO AT RISK OF DEVELOPING HEPATOCELLULAR CARCINOMA (HCC). EPIGENETIC MECHANISMS OF NUCLEAR CHROMATIN REMODELING, SUCH AS DNA METHYLATION, POST-TRANSLATIONAL MODIFICATIONS OF HISTONES, AND INCORPORATION OF HISTONE VARIANTS INTO THE CHROMATIN ARE INCREASINGLY RECOGNIZED AS CRUCIAL FACTORS IN THE PATHOPHYSIOLOGY OF NAFLD. NAFLD IS OFTEN ACCOMPANIED BY OXIDATIVE STRESS: REACTIVE OXYGEN SPECIES (ROS) ARE IMPLICATED IN ALTERED REDUCTION/OXIDATION (REDOX) REACTIONS THAT ATTACK CELLULAR MACROMOLECULES AND ARE DETECTED IN THE LIVER OF PATIENTS AND ANIMAL MODELS OF NAFLD. IN THIS REVIEW, WE SUMMARIZE RECENT KNOWLEDGE ADVANCEMENTS IN THE HEPATIC EPIGENETIC AND REDOX MECHANISMS, AND THEIR POSSIBLE LINKS, INVOLVED IN THE PATHOGENESIS AND TREATMENT OF NAFLD. 2013 13 2954 39 GENETIC AND EPIGENETIC FACTORS DETERMINING NAFLD RISK. BACKGROUND: HEPATIC STEATOSIS IS A COMMON CHRONIC LIVER DISEASE THAT CAN PROGRESS INTO MORE SEVERE STAGES OF NAFLD OR PROMOTE THE DEVELOPMENT OF LIFE-THREATENING SECONDARY DISEASES FOR SOME OF THOSE AFFECTED. THESE INCLUDE THE LIVER ITSELF (NONALCOHOLIC STEATOHEPATITIS OR NASH; FIBROSIS AND CIRRHOSIS, AND HEPATOCELLULAR CARCINOMA) OR OTHER ORGANS SUCH AS THE VESSELS AND THE HEART (CARDIOVASCULAR DISEASE) OR THE ISLETS OF LANGERHANS (TYPE 2 DIABETES). IN ADDITION TO ELEVATED CALORIC INTAKE AND A SEDENTARY LIFESTYLE, GENETIC AND EPIGENETIC PREDISPOSITION CONTRIBUTE TO THE DEVELOPMENT OF NAFLD AND THE SECONDARY DISEASES. SCOPE OF REVIEW: WE PRESENT DATA FROM GENOME-WIDE ASSOCIATION STUDIES (GWAS) AND FUNCTIONAL STUDIES IN RODENTS WHICH DESCRIBE POLYMORPHISMS IDENTIFIED IN GENES RELEVANT FOR THE DISEASE AS WELL AS CHANGES CAUSED BY ALTERED DNA METHYLATION AND GENE REGULATION VIA SPECIFIC MIRNAS. THE REVIEW ALSO PROVIDES INFORMATION ON THE CURRENT STATUS OF THE USE OF GENETIC AND EPIGENETIC FACTORS AS RISK MARKERS. MAJOR CONCLUSION: WITH OUR OVERVIEW WE PROVIDE AN INSIGHT INTO THE GENETIC AND EPIGENETIC LANDSCAPE OF NAFLD AND ARGUE ABOUT THE APPLICABILITY OF CURRENTLY DEFINED RISK SCORES FOR RISK STRATIFICATION AND CONCLUDE THAT FURTHER EFFORTS ARE NEEDED TO MAKE THE SCORES MORE USABLE AND MEANINGFUL. 2021 14 1491 38 DNA HYDROXYMETHYLATION AT THE INTERFACE OF THE ENVIRONMENT AND NONALCOHOLIC FATTY LIVER DISEASE. NON-ALCOHOLIC FATTY LIVER DISEASE (NAFLD) IS ONE OF THE MOST PREVALENT FORMS OF CHRONIC LIVER DISORDERS AMONG ADULTS, CHILDREN, AND ADOLESCENTS, AND A GROWING EPIDEMIC, WORLDWIDE. NOTWITHSTANDING THE KNOWN SUSCEPTIBILITY FACTORS FOR NAFLD, I.E., OBESITY AND METABOLIC SYNDROME, THE EXACT CAUSE(S) OF THIS DISEASE AND THE UNDERLYING MECHANISMS OF ITS INITIATION AND PROGRESSION ARE NOT FULLY ELUCIDATED. NAFLD IS A MULTI-FACETED DISEASE WITH METABOLIC, GENETIC, EPIGENETIC, AND ENVIRONMENTAL DETERMINANTS. ACCUMULATING EVIDENCE SHOWS THAT EXPOSURE TO ENVIRONMENTAL TOXICANTS CONTRIBUTES TO THE DEVELOPMENT OF NAFLD BY PROMOTING MITOCHONDRIAL DYSFUNCTION AND GENERATING REACTIVE OXYGEN SPECIES IN THE LIVER. IMBALANCES IN THE REDOX STATE OF THE CELLS ARE KNOWN TO CAUSE ALTERATIONS IN THE PATTERNS OF 5-HYDROXYMETHYLCYTOSINE (5HMC), THE OXIDATIVE PRODUCT OF 5-METHYLCYTOSINE (5MC), THEREBY INFLUENCING GENE REGULATION. THE 5HMC-MEDIATED DEREGULATION OF GENES INVOLVED IN HEPATIC METABOLISM IS AN EMERGING AREA OF RESEARCH IN NAFLD. THIS REVIEW SUMMARIZES OUR CURRENT KNOWLEDGE ON THE INTERACTIVE ROLE OF XENOBIOTIC EXPOSURE AND DNA HYDROXYMETHYLATION IN THE PATHOGENESIS OF FATTY LIVER DISEASE. INCREASING THE MECHANISTIC KNOWLEDGE OF NAFLD INITIATION AND PROGRESSION IS CRUCIAL FOR THE DEVELOPMENT OF NEW AND EFFECTIVE STRATEGIES FOR PREVENTION AND TREATMENT OF THIS DISEASE. 2019 15 4190 35 METABOLIC DYSFUNCTION-ASSOCIATED FATTY LIVER DISEASE: ADVANCES IN GENETIC AND EPIGENETIC IMPLICATIONS. PURPOSE OF REVIEW: FATTY LIVER ASSOCIATED WITH METABOLIC DYSFUNCTION, ALSO KNOWN UNDER THE ACRONYM NAFLD (NONALCOHOLIC FATTY LIVER DISEASE) IS THE LEADING GLOBAL CAUSE OF CHRONIC LIVER DISEASE. IN THIS REVIEW, WE ADDRESS THE STATE OF RESEARCH ON GENETICS AND EPIGENETICS OF NAFLD WITH FOCUS ON KEY DISCOVERIES AND CONCEPTUAL ADVANCES OVER THE PAST 2 YEARS. RECENT FINDINGS: THE ANALYSIS OF NAFLD-ASSOCIATED GENETIC VARIANT EFFECTS ON THE WHOLE-TRANSCRIPTOME, INCLUDING QUANTITATIVE TRAIT LOCI (QTL) ASSOCIATED WITH GENE EXPRESSION (EQTL) OR SPLICING (SQTL) MAY EXPLAIN PLEIOTROPIC EFFECTS. FUNCTIONAL EXPERIMENTS ON NAFLD-EPIGENETICS, INCLUDING PROFILING OF LIVER CHROMATIN ACCESSIBILITY QUANTITATIVE TRAIT LOCI (CAQTL) SHOW CO-LOCALIZATION WITH NUMEROUS GENOME-WIDE ASSOCIATION STUDY SIGNALS LINKED TO METABOLIC AND CARDIOVASCULAR TRAITS. NOVEL STUDIES PROVIDE INSIGHTS INTO THE MODULATION OF THE HEPATIC TRANSCRIPTOME AND EPIGENOME BY TISSUE MICROBIOTAS. GENETIC VARIATION OF COMPONENTS OF THE LIVER CELLULAR RESPIRASOME MAY RESULT IN BROAD CELLULAR AND METABOLIC EFFECTS. MITOCHONDRIAL NONCODING RNAS MAY REGULATE LIVER INFLAMMATION AND FIBROGENESIS. RNA MODIFICATIONS AS N6-METHYLADENOSINE MAY EXPLAIN SEX-SPECIFIC DIFFERENCES IN LIVER GENE TRANSCRIPTION LINKED TO LIPID TRAITS. SUMMARY: THE LATEST DEVELOPMENTS IN THE FIELD OF NAFLD-GENOMICS CAN BE LEVERAGED FOR IDENTIFYING NOVEL DISEASE MECHANISMS AND THERAPEUTIC TARGETS THAT MAY PREVENT THE MORBIDITY AND MORTALITY ASSOCIATED WITH DISEASE PROGRESSION. VIDEO ABSTRACT: HTTP://LINKS.LWW.COM/COL/A23. 2022 16 1587 35 DNA METHYLATION PROFILING IDENTIFIES NOVEL MARKERS OF PROGRESSION IN HEPATITIS B-RELATED CHRONIC LIVER DISEASE. BACKGROUND: CHRONIC HEPATITIS B INFECTION IS CHARACTERIZED BY HEPATIC IMMUNE AND INFLAMMATORY RESPONSE WITH CONSIDERABLE VARIATION IN THE RATES OF PROGRESSION TO CIRRHOSIS. GENETIC VARIANTS AND ENVIRONMENTAL CUES INFLUENCE PREDISPOSITION TO THE DEVELOPMENT OF CHRONIC LIVER DISEASE; HOWEVER, IT REMAINS UNKNOWN IF ABERRANT DNA METHYLATION IS ASSOCIATED WITH FIBROSIS PROGRESSION IN CHRONIC HEPATITIS B. RESULTS: TO IDENTIFY EPIGENETIC MARKS ASSOCIATED WITH INFLAMMATORY AND FIBROTIC PROCESSES OF THE HEPATITIS B-INDUCED CHRONIC LIVER DISEASE, WE CARRIED OUT HEPATIC GENOME-WIDE METHYLATION PROFILING USING ILLUMINA INFINIUM BEADARRAYS COMPARING MILD AND SEVERE FIBROTIC DISEASE IN A DISCOVERY COHORT OF 29 PATIENTS. WE OBTAINED 310 DIFFERENTIALLY METHYLATED REGIONS AND SELECTED FOUR LOCI COMPRISING THREE GENES FROM THE TOP DIFFERENTIALLY METHYLATED REGIONS: HYPERMETHYLATION OF HOXA2 AND HDAC4 ALONG WITH HYPOMETHYLATION OF PPP1R18 WERE SIGNIFICANTLY LINKED TO SEVERE FIBROSIS. WE REPLICATED THE PROMINENT METHYLATION MARKS IN AN INDEPENDENT COHORT OF 102 PATIENTS BY BISULFITE MODIFICATION AND PYROSEQUENCING. THE TIMING AND CAUSAL RELATIONSHIP OF EPIGENETIC MODIFICATIONS WITH DISEASE SEVERITY WAS FURTHER INVESTIGATED USING A COHORT OF PATIENTS WITH SERIAL BIOPSIES. CONCLUSIONS: OUR FINDINGS SUGGEST A LINKAGE OF WIDESPREAD EPIGENETIC DYSREGULATION WITH DISEASE PROGRESSION IN CHRONIC HEPATITIS B INFECTION. CPG METHYLATION AT NOVEL GENES SHEDS LIGHT ON NEW MOLECULAR PATHWAYS, WHICH CAN BE POTENTIALLY EXPLOITED AS A BIOMARKER OR TARGETED TO ATTENUATE INFLAMMATION AND FIBROSIS. 2016 17 4722 41 NONCODING RNAS IN NONALCOHOLIC FATTY LIVER DISEASE: POTENTIAL DIAGNOSIS AND PROGNOSIS BIOMARKERS. NONALCOHOLIC FATTY LIVER DISEASE (NAFLD) IS CURRENTLY THE MOST COMMON CHRONIC LIVER DISEASE WORLDWIDE IN PART DUE TO THE CONCOMITANT OBESITY PANDEMIC AND INSULIN RESISTANCE (IR). IT IS INCREASINGLY BECOMING EVIDENT THAT NAFLD IS A DISEASE AFFECTING NUMEROUS EXTRAHEPATIC VITAL ORGANS AND REGULATORY PATHWAYS. THE MOLECULAR MECHANISMS UNDERLYING THE NONALCOHOLIC STEATOSIS FORMATION ARE POORLY UNDERSTOOD, AND LITTLE INFORMATION IS AVAILABLE ON THE PATHWAYS THAT ARE RESPONSIBLE FOR THE PROGRESSIVE HEPATOCELLULAR DAMAGE THAT FOLLOWS LIPID ACCUMULATION. RECENTLY, MUCH RESEARCH HAS FOCUSED ON THE IDENTIFICATION OF THE EPIGENETIC MODIFICATIONS THAT CONTRIBUTE TO NAFLD PATHOGENESIS. NONCODING RNAS (NCRNAS) ARE ONE OF SUCH EPIGENETIC FACTORS THAT COULD BE IMPLICATED IN THE NAFLD DEVELOPMENT AND PROGRESSION. IN THIS REVIEW, WE SUMMARIZE THE CURRENT KNOWLEDGE OF THE GENETIC AND EPIGENETIC FACTORS POTENTIALLY UNDERLYING THE DISEASE. PARTICULAR EMPHASIS WILL BE PUT ON THE CONTRIBUTION OF MICRORNAS (MIRNAS), LONG NONCODING RNAS (LNCRNAS), AND CIRCULAR RNAS (CIRCRNAS) TO THE PATHOPHYSIOLOGY OF NAFLD AS WELL AS THEIR POTENTIAL USE AS THERAPEUTIC TARGETS OR AS MARKERS FOR THE PREDICTION AND THE PROGRESSION OF THE DISEASE. 2020 18 4884 34 OVERVIEW OF THE PATHOGENESIS, GENETIC, AND NON-INVASIVE CLINICAL, BIOCHEMICAL, AND SCORING METHODS IN THE ASSESSMENT OF NAFLD. NONALCOHOLIC FATTY LIVER DISEASE (NAFLD) IS THE MOST PREVALENT CHRONIC LIVER DISEASE WORLDWIDE. IT REPRESENTS A RANGE OF DISORDERS, INCLUDING SIMPLE STEATOSIS, NONALCOHOLIC STEATOHEPATITIS (NASH), AND LIVER CIRRHOSIS, AND ITS PREVALENCE CONTINUES TO RISE. IN SOME CASES, HEPATOCELLULAR CARCINOMA (HCC) MAY DEVELOP. THE DEVELOP;MENT OF NON-INVASIVE DIAGNOSTIC AND SCREENING TOOLS IS NEEDED, IN ORDER TO REDUCE THE FREQUENCY OF LIVER BIOPSIES. THE MOST PROMISING METHODS ARE THOSE ABLE TO EXCLUDE ADVANCED FIBROSIS AND QUANTIFY STEATOSIS. IN THIS STUDY, NEW PERSPECTIVE MARKERS FOR INFLAMMATION, OXIDATIVE STRESS, APOPTOSIS, AND FIBROGENESIS; EMERGING SCORING MODELS FOR DETECTING HEPATIC STEATOSIS AND FIBROSIS; AND NEW GENETIC, EPIGENETIC, AND MULTIOMIC STUDIES ARE DISCUSSED. AS ISOLATED BIOCHEMICAL PARAMETERS ARE NOT SPECIFIC OR SENSITIVE ENOUGH TO PREDICT THE PRESENCE OF NASH AND FIBROSIS, THERE IS A TENDENCY TO USE VARIOUS MARKERS AND COMBINE THEM INTO MATHEMATICAL ALGORITHMS. SEVERAL PREDICTIVE MODELS AND SCORING SYSTEMS HAVE BEEN DEVELOPED. CURRENT DATA SUGGESTS THAT PANELS OF MARKERS (NAFLD FIBROSIS SCORE, FIB-4 SCORE, BARD SCORE, AND OTHERS) ARE USEFUL DIAGNOSTIC MODALITIES TO MINIMIZE THE NUMBER OF LIVER BIOPSIES. THE REVIEW UNVEILS PATHOPHYSIOLOGICAL ASPECTS RELATED TO NEW TRENDS IN CURRENT NON-INVASIVE BIOCHEMICAL, GENETIC, AND SCORING METHODS, AND PROVIDES INSIGHT INTO THEIR DIAGNOSTIC ACCURACIES AND SUITABILITY IN CLINICAL PRACTICE. 2019 19 3293 39 HIGH FAT DIET-TRIGGERED NON-ALCOHOLIC FATTY LIVER DISEASE: A REVIEW OF PROPOSED MECHANISMS. OBESITY IS CHARACTERIZED BY THE DEPOSITION OF EXCESSIVE BODY FAT, AND IS CAUSED BY ENERGY IMBALANCE, ESPECIALLY WHEN CONSUMING FAT-RICH DIETS. HIGH FAT DIET (HFD)-ASSOCIATED OBESITY IS GREATLY COMMON IN PATIENTS WITH NON-ALCOHOLIC FATTY LIVER DISEASE (NAFLD) THAT IS EMERGING AS ONE OF THE MOST UNIVERSAL CAUSES OF LIVER DISEASE WORLDWIDE, ESPECIALLY IN WESTERN COUNTRIES. IN SPITE OF ITS HIGH PREVALENCE, ONLY A SMALL PROPORTION OF AFFECTED INDIVIDUALS WILL BECOME INFLAMED, FOLLOWED BY FIBROSIS AND CHRONIC LIVER DISEASES, AND MOST PATIENTS ONLY SHOW SIMPLE STEATOSIS. IN THIS CASE, THE FULL COMPREHENSION OF THE MECHANISMS UNDERLYING THE PROGRESSION OF NAFLD IS OF EXTREME SIGNIFICANCE; IN SPITE OF PROGRESS IN THIS FIELD, AWARENESS ON THE DEVELOPMENT OF NAFLD IS STILL INCOMPLETE. TRADITIONALLY, LIVER STEATOSIS IS COMMONLY CONNECTED WITH HFD, OBESITY, AND INSULIN RESISTANCE (IR). RECENTLY, VARIOUS POSSIBLE MECHANISMS HAVE BEEN PUT FORWARD FOR LIVER DAMAGE, INCLUDING ENDOPLASMIC RETICULUM STRESS, PERTURBATION OF AUTOPHAGY, MITOCHONDRIAL DYSFUNCTION, HEPATOCELLULAR APOPTOSIS, GUT MICROBIOTA IMBALANCE, DYSREGULATION OF MICRORNAS, AND GENETIC/EPIGENETIC RISK FACTORS, AS WELL AS AN INCREASE IN INFLAMMATORY RESPONSES, AMONG MANY OTHERS. COLLECTIVELY, THESE PROPOSED MECHANISMS ALLOW FOR A VARIETY OF HITS ACTING TOGETHER ON SUBJECTS TO MEDIATED NAFLD AND WILL OFFER A MORE ACCURATE EXPLANATION FOR PROGRESSION OF NAFLD. THEREFORE, THIS REVIEW SUMMARIZES THE PRESENT INFORMATION CONCERNING NAFLD AFTER HFD EXPOSURE, AS WELL AS DISCUSSES POSSIBLE MECHANISMS THROUGH WHICH IT MAY ARISE. 2020 20 2909 45 GENE EXPRESSION PROFILING IN FIBROMYALGIA INDICATES AN AUTOIMMUNE ORIGIN OF THE DISEASE AND OPENS NEW AVENUES FOR TARGETED THERAPY. FIBROMYALGIA IS A CHRONIC DISORDER CHARACTERIZED BY WIDESPREAD PAIN AND BY SEVERAL NON-PAIN SYMPTOMS. AUTOIMMUNITY, SMALL FIBER NEUROPATHY AND NEUROINFLAMMATION HAVE BEEN SUGGESTED TO BE INVOLVED IN THE PATHOGENESIS OF THE DISEASE. WE HAVE INVESTIGATED THE GENE EXPRESSION PROFILE IN PERIPHERAL BLOOD MONONUCLEAR CELLS OBTAINED FROM TEN PATIENTS AND TEN HEALTHY SUBJECTS. OF THE 545,500 TRANSCRIPTS ANALYZED, 1673 RESULTED MODULATED IN FIBROMYALGIC PATIENTS. THE MAJORITY OF THESE GENES ARE INVOLVED IN BIOLOGICAL PROCESSES AND PATHWAYS LINKED TO THE CLINICAL MANIFESTATIONS OF THE DISEASE. MOREOVER, GENES INVOLVED IN IMMUNOLOGICAL PATHWAYS CONNECTED TO INTERLEUKIN-17 AND TO TYPE I INTERFERON SIGNATURES WERE ALSO MODULATED, SUGGESTING THAT AUTOIMMUNITY PLAYS A ROLE IN THE DISEASE. WE THEN AIMED AT IDENTIFYING DIFFERENTIALLY EXPRESSED LONG NON-CODING RNAS (LNCRNAS) FUNCTIONALLY CONNECTED TO MODULATED GENES BOTH DIRECTLY AND VIA MICRORNA TARGETING. ONLY TWO LNCRNAS OF THE 298 FOUND MODULATED IN PATIENTS, WERE ABLE TO TARGET THE MOST HIGHLY CONNECTED GENES IN THE FIBROMYALGIA INTERACTOME, SUGGESTING THEIR INVOLVEMENT IN CRUCIAL GENE REGULATION. OUR GENE EXPRESSION DATA WERE CONFIRMED BY REAL TIME PCR, BY AUTOANTIBODY TESTING, DETECTION OF SOLUBLE MEDIATORS AND TH-17 POLARIZATION IN A VALIDATION COHORT OF 50 PATIENTS. OUR RESULTS INDICATE THAT GENETIC AND EPIGENETIC MECHANISMS AS WELL AS AUTOIMMUNITY PLAY A PIVOTAL ROLE IN THE PATHOGENESIS OF FIBROMYALGIA. 2020