1 6900 142 [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 2 3022 36 GENETICS AND EPIGENETICS PURPOSE IN NONALCOHOLIC FATTY LIVER DISEASE. INTRODUCTION: NONALCOHOLIC FATTY LIVER DISEASE (NAFLD) COMPRISES A BROAD SPECTRUM OF DISEASES, WHICH CAN PROGRESS FROM BENIGN STEATOSIS TO NONALCOHOLIC STEATOHEPATITIS, LIVER CIRRHOSIS AND HEPATOCELLULAR CARCINOMA. NAFLD IS THE MOST COMMON CHRONIC LIVER DISEASE IN DEVELOPED COUNTRIES, AFFECTING APPROXIMATELY 25% OF THE GENERAL POPULATION. INSULIN RESISTANCE, ADIPOSE TISSUE DYSFUNCTION, MITOCHONDRIAL AND ENDOPLASMIC RETICULUM STRESS, CHRONIC INFLAMMATION, GENETIC AND EPIGENETIC FACTORS ARE NAFLD TRIGGERS THAT CONTROL THE DISEASE SUSCEPTIBILITY AND PROGRESSION. AREAS COVERED: IN RECENT YEARS A LARGE NUMBER OF INVESTIGATIONS HAVE BEEN CARRIED OUT TO ELUCIDATE GENETIC AND EPIGENETIC FACTORS IN THE DISEASE PATHOGENESIS, AS WELL AS THE SEARCH FOR DIAGNOSTIC MARKERS AND THERAPEUTIC TARGETS. THIS PAPER OBJECTIVE IS TO REPORT THE MOST STUDIED GENETIC AND EPIGENETIC VARIANTS AROUND NAFLD. EXPERT OPINION: NAFLD LEAD TO VARIOUS COMORBIDITIES, WHICH HAVE A CONSIDERABLE IMPACT ON THE PATIENT WELLNESS AND LIFE QUALITY, AS WELL AS ON THE COSTS THEY GENERATE FOR THE COUNTRY'S HEALTH SERVICES. IT IS ESSENTIAL TO CONTINUE WITH MOLECULAR RESEARCH, SINCE IT COULD BE USED AS A CLINICAL TOOL FOR PROGNOSIS AND DISEASE SEVERITY. SPECIFICALLY, IN THE FIELD OF HEPATOLOGY, PLASMA MIRNAS COULD PROVIDE A NOVEL TOOL IN LIVER DISEASES DIAGNOSIS AND MONITORING, REPRESENTING AN ALTERNATIVE TO INVASIVE DIAGNOSTIC PROCEDURES. 2020 3 4369 36 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 4 2954 33 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 5 1285 33 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 6 3293 43 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 7 4710 32 NON-ALCOHOLIC FATTY LIVER DISEASE AND THE IMPACT OF GENETIC, EPIGENETIC AND ENVIRONMENTAL FACTORS IN THE OFFSPRING. NON-ALCOHOLIC FATTY LIVER DISEASE (NAFLD) IS THE MOST COMMON CHRONIC LIVER DISEASE WORLDWIDE AND IS STRONGLY ASSOCIATED WITH METABOLIC DEREGULATION. MORE RECENTLY, A SIGNIFICANT IMPACT OF PARENTAL NAFLD IN THE OFFSPRING WAS DEMONSTRATED AND HAS BEEN WIDELY DISCUSSED. HOWEVER, PATHOGENETIC PATHWAYS IMPLICATED IN THE INHERITANCE BY THE OFFSPRING AND RELATIVES ARE STILL UNDER DEBATE. PROBABLY, MULTIPLE MECHANISMS ARE INVOLVED AS WELL AS IN NAFLD PATHOGENESIS ITSELF. AMONG THE MULTIFACTORIAL INVOLVED MECHANISMS, GENETIC, EPIGENETIC AND ENVIRONMENTAL BACKGROUNDS ARE STRONGLY RELATED TO NAFLD DEVELOPMENT IN THE OFFSPRING. THUS, BASED ON RECENT EVIDENCE FROM THE AVAILABLE LITERATURE CONCERNING GENETIC, EPIGENETIC AND ENVIRONMENTAL DISEASE MODIFIERS, THIS REVIEW AIMED TO DISCUSS THE RELATIONSHIP BETWEEN PARENTAL NAFLD AND ITS IMPACT ON THE OFFSPRING. 2022 8 4722 42 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 9 4314 35 MICRORNAS AS CONTROLLED SYSTEMS AND CONTROLLERS IN NON-ALCOHOLIC FATTY LIVER DISEASE. NON-ALCOHOLIC FATTY LIVER DISEASE (NAFLD) IS A MULTI-FACETED CONDITION INCLUDING SIMPLE STEATOSIS ALONE OR ASSOCIATED WITH INFLAMMATION AND BALLOONING (NON-ALCOHOLIC STEATOHEPATITIS) AND EVENTUALLY FIBROSIS. THE NAFLD INCIDENCE HAS INCREASED OVER THE LAST TWENTY YEARS BECOMING THE MOST FREQUENT CHRONIC LIVER DISEASE IN INDUSTRIALIZED COUNTRIES. OBESITY, VISCERAL ADIPOSITY, INSULIN RESISTANCE, AND MANY OTHER DISORDERS THAT CHARACTERIZE METABOLIC SYNDROME ARE THE MAJOR PREDISPOSING RISK FACTORS FOR NAFLD. FURTHERMORE, DIFFERENT FACTORS, INCLUDING GENETIC BACKGROUND, EPIGENETIC MECHANISMS AND ENVIRONMENTAL FACTORS, SUCH AS DIET AND PHYSICAL EXERCISE, CONTRIBUTE TO NAFLD DEVELOPMENT AND PROGRESSION. SEVERAL LINES OF EVIDENCE DEMONSTRATE THAT SPECIFIC MICRORNAS EXPRESSION PROFILES ARE STRONGLY ASSOCIATED WITH SEVERAL PATHOLOGICAL CONDITIONS INCLUDING NAFLD. IN NAFLD, MICRORNA DEREGULATION IN RESPONSE TO INTRINSIC GENETIC OR EPIGENETIC FACTORS OR ENVIRONMENTAL FACTORS CONTRIBUTES TO METABOLIC DYSFUNCTION. IN THIS REVIEW WE FOCUSED ON MICRORNAS ROLE BOTH AS CONTROLLED AND CONTROLLERS MOLECULES IN NAFLD DEVELOPMENT AND/OR THEIR EVENTUAL VALUE AS NON-INVASIVE BIOMARKERS OF DISEASE. 2014 10 2544 31 EPIGENETICS IN LIVER DISEASE: FROM BIOLOGY TO THERAPEUTICS. KNOWLEDGE OF THE FUNDAMENTAL EPIGENETIC MECHANISMS GOVERNING GENE EXPRESSION AND CELLULAR PHENOTYPE ARE SUFFICIENTLY ADVANCED THAT NOVEL INSIGHTS INTO THE EPIGENETIC CONTROL OF CHRONIC LIVER DISEASE ARE NOW EMERGING. HEPATOLOGISTS ARE IN THE PROCESS OF SHEDDING LIGHT ON THE ROLES PLAYED BY DNA METHYLATION, HISTONE/CHROMATIN MODIFICATIONS AND NON-CODING RNAS IN SPECIFIC LIVER PATHOLOGIES. ALONGSIDE THESE DISCOVERIES ARE ADVANCES IN THE TECHNOLOGIES FOR THE DETECTION AND QUANTIFICATION OF EPIGENETIC BIOMARKERS, EITHER DIRECTLY FROM PATIENT TISSUE OR FROM BODY FLUIDS. THE PREMISE FOR THIS REVIEW IS TO SURVEY THE RECENT ADVANCES IN THE FIELD OF LIVER EPIGENETICS AND TO EXPLORE THEIR POTENTIAL FOR TRANSLATION BY INDUSTRY AND CLINICAL HEPATOLOGISTS FOR THE DESIGN OF NOVEL THERAPEUTICS AND DIAGNOSTIC/PROGNOSTIC BIOMARKERS. IN PARTICULAR, WE PRESENT FINDINGS IN THE CONTEXT OF HEPATOCELLULAR CARCINOMA, FIBROSIS AND NON-ALCOHOLIC FATTY LIVER DISEASE, WHERE THERE IS URGENT UNMET NEED FOR NEW CLINICAL INTERVENTIONS AND BIOMARKERS. 2016 11 4884 43 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 12 1128 34 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 13 4720 41 NONCODING RNAS AS ADDITIONAL MEDIATORS OF EPIGENETIC REGULATION IN NONALCOHOLIC FATTY LIVER DISEASE. NONALCOHOLIC FATTY LIVER DISEASE (NAFLD) HAS EMERGED AS THE MOST COMMON CAUSE OF CHRONIC LIVER DISORDER WORLDWIDE. IT REPRESENTS A SPECTRUM THAT INCLUDES A CONTINUUM OF DIFFERENT CLINICAL ENTITIES RANGING FROM SIMPLE STEATOSIS TO NONALCOHOLIC STEATOHEPATITIS, WHICH CAN EVOLVE TO CIRRHOSIS AND IN SOME CASES TO HEPATOCELLULAR CARCINOMA, ULTIMATELY LEADING TO LIVER FAILURE. THE PATHOGENESIS OF NAFLD AND THE MECHANISMS UNDERLYING ITS PROGRESSION TO MORE PATHOLOGICAL STAGES ARE NOT COMPLETELY UNDERSTOOD. BESIDES GENETIC FACTORS, EVIDENCE INDICATES THAT EPIGENETIC MECHANISMS OCCURRING IN RESPONSE TO ENVIRONMENTAL STIMULI ALSO CONTRIBUTE TO THE DISEASE RISK. NONCODING RNAS (NCRNAS), INCLUDING MICRORNAS, LONG NONCODING RNAS, AND CIRCULAR RNAS, ARE ONE OF THE EPIGENETIC FACTORS THAT PLAY KEY REGULATORY ROLES IN THE DEVELOPMENT OF NAFLD. AS THE FIELD OF NCRNAS IS RAPIDLY EVOLVING, THE PRESENT REVIEW AIMS TO EXPLORE THE CURRENT STATE OF KNOWLEDGE ON THE ROLES OF THESE RNA SPECIES IN THE PATHOGENESIS OF NAFLD, HIGHLIGHT RELEVANT MECHANISMS BY WHICH SOME NCRNAS CAN MODULATE REGULATORY NETWORKS IMPLICATED IN NAFLD, AND DISCUSS KEY CHALLENGES AND FUTURE DIRECTIONS FACING CURRENT RESEARCH IN THE HOPES OF DEVELOPING NCRNAS AS NEXT-GENERATION NON-INVASIVE DIAGNOSTICS AND THERAPIES IN NAFLD AND SUBSEQUENT PROGRESSION TO HEPATOCELLULAR CARCINOMA. 2022 14 4991 41 PEDIATRIC NON-ALCOHOLIC FATTY LIVER DISEASE: NUTRITIONAL ORIGINS AND POTENTIAL MOLECULAR MECHANISMS. NON-ALCOHOLIC FATTY LIVER DISEASE (NAFLD) IS THE NUMBER ONE CHRONIC LIVER DISEASE WORLDWIDE AND IS ESTIMATED TO AFFECT NEARLY 40% OF OBESE YOUTH AND UP TO 10% OF THE GENERAL PEDIATRIC POPULATION WITHOUT ANY OBVIOUS SIGNS OR SYMPTOMS. ALTHOUGH THE EARLY STAGES OF NAFLD ARE REVERSIBLE WITH DIET AND LIFESTYLE MODIFICATIONS, DETECTING SUCH STAGES IS HINDERED BY A LACK OF NON-INVASIVE METHODS OF RISK ASSESSMENT AND DIAGNOSIS. THIS ABSENCE OF NON-INVASIVE MEANS OF DIAGNOSIS IS DIRECTLY RELATED TO THE SCARCITY OF LONG-TERM PROSPECTIVE STUDIES OF PEDIATRIC NAFLD IN CHILDREN AND ADOLESCENTS. IN THE MAJORITY OF PEDIATRIC NAFLD CASES, THE MECHANISMS DRIVING THE ORIGIN AND RAPID PROGRESSION OF NAFLD REMAIN UNKNOWN. THE PROGRESSION FROM NAFLD TO NON-ALCOHOLIC STEATOHEPATITIS (NASH) IN YOUTH IS ASSOCIATED WITH UNIQUE HISTOLOGICAL FEATURES AND POSSIBLE IMMUNE PROCESSES AND METABOLIC PATHWAYS THAT MAY REFLECT DIFFERENT MECHANISMS COMPARED WITH ADULTS. RECENT DATA SUGGEST THAT CIRCULATING MICRORNAS (MIRNAS) ARE IMPORTANT NEW BIOMARKERS UNDERLYING PATHWAYS OF LIVER INJURY. SEVERAL FACTORS MAY CONTRIBUTE TO PEDIATRIC NAFLD DEVELOPMENT, INCLUDING HIGH-SUGAR DIETS, IN UTERO EXPOSURES VIA EPIGENETIC ALTERATIONS, CHANGES IN THE NEONATAL MICROBIOME, AND ALTERED IMMUNE SYSTEM DEVELOPMENT AND MITOCHONDRIAL FUNCTION. THIS REVIEW FOCUSES ON THE UNIQUE ASPECTS OF PEDIATRIC NAFLD AND HOW NUTRITIONAL EXPOSURES IMPACT THE IMMUNE SYSTEM, MITOCHONDRIA, AND LIVER/GASTROINTESTINAL METABOLIC HEALTH. THESE FACTORS HIGHLIGHT THE NEED FOR ANSWERS TO HOW NAFLD DEVELOPS IN CHILDREN AND FOR EARLY STAGE-SPECIFIC INTERVENTIONS. 2020 15 2287 33 EPIGENETIC REGULATION IN LEAN NONALCOHOLIC FATTY LIVER DISEASE. NONALCOHOLIC FATTY LIVER DISEASE (NAFLD), THE MOST PROMINENT CAUSE OF CHRONIC LIVER DISEASE WORLDWIDE, IS A RAPIDLY GROWING EPIDEMIC. IT CONSISTS OF A WIDE RANGE OF LIVER DISEASES, FROM STEATOSIS TO NONALCOHOLIC STEATOHEPATITIS, AND PREDISPOSES PATIENTS TO LIVER FIBROSIS, CIRRHOSIS, AND EVEN HEPATOCELLULAR CARCINOMA. NAFLD IS STRONGLY CORRELATED WITH OBESITY; HOWEVER, IT HAS BEEN EXTENSIVELY REPORTED AMONG LEAN/NONOBESE INDIVIDUALS IN RECENT YEARS. ALTHOUGH LEAN PATIENTS DEMONSTRATE A LOWER PREVALENCE OF DIABETES MELLITUS, CENTRAL OBESITY, DYSLIPIDEMIA, HYPERTENSION, AND METABOLIC SYNDROME, A PERCENTAGE OF THESE PATIENTS MAY DEVELOP STEATOHEPATITIS, ADVANCED LIVER FIBROSIS, AND CARDIOVASCULAR DISEASE, AND HAVE INCREASED ALL-CAUSE MORTALITY. THE PATHOPHYSIOLOGICAL MECHANISMS OF LEAN NAFLD REMAIN VAGUE. STUDIES HAVE REPORTED THAT LEAN NAFLD DEMONSTRATES A CLOSE ASSOCIATION WITH ENVIRONMENTAL FACTORS, GENETIC PREDISPOSITION, AND EPIGENETIC MODIFICATIONS. IN THIS REVIEW, WE AIM TO DISCUSS AND SUMMARIZE THE EPIGENETIC MECHANISMS INVOLVED IN LEAN NAFLD AND TO INTRODUCE THE INTERACTION BETWEEN EPIGENETIC PATTERNS AND GENETIC OR NON GENETIC FACTORS. SEVERAL EPIGENETIC MECHANISMS HAVE BEEN IMPLICATED IN THE REGULATION OF LEAN NAFLD. THESE INCLUDE DNA METHYLATION, HISTONE MODIFICATIONS, AND NONCODING-RNA-MEDIATED GENE REGULATION. EPIGENETICS IS AN AREA OF SPECIAL INTEREST IN THE SETTING OF LEAN NAFLD AS IT COULD PROVIDE NEW INSIGHTS INTO THE THERAPEUTIC OPTIONS AND NONINVASIVE BIOMARKERS THAT TARGET THIS UNDER-RECOGNIZED AND CHALLENGING DISORDER. 2023 16 1858 38 ELUCIDATING POTENTIAL PROFIBROTIC MECHANISMS OF EMERGING BIOMARKERS FOR EARLY PROGNOSIS OF HEPATIC FIBROSIS. HEPATIC FIBROSIS HAS BEEN ASSOCIATED WITH A SERIES OF PATHOPHYSIOLOGICAL PROCESSES CAUSING EXCESSIVE ACCUMULATION OF EXTRACELLULAR MATRIX PROTEINS. SEVERAL CELLULAR PROCESSES AND MOLECULAR MECHANISMS HAVE BEEN IMPLICATED IN THE DISEASED LIVER THAT AUGMENTS FIBROGENESIS, FIBROGENIC CYTOKINES AND ASSOCIATED LIVER COMPLICATIONS. LIVER BIOPSY REMAINS AN ESSENTIAL DIAGNOSTIC TOOL FOR HISTOLOGICAL EVALUATION OF HEPATIC FIBROSIS TO ESTABLISH A PROGNOSIS. IN ADDITION TO BEING INVASIVE, THIS METHODOLOGY PRESENTS WITH SEVERAL LIMITATIONS INCLUDING POOR COST-EFFECTIVENESS, PROLONGED HOSPITALIZATIONS, AND RISKS OF PERITONEAL BLEEDING, WHILE THE CLINICAL USE OF THIS METHOD DOES NOT REVEAL UNDERLYING PATHOGENIC MECHANISMS. SEVERAL ALTERNATE NONINVASIVE DIAGNOSTIC STRATEGIES HAVE BEEN DEVELOPED, TO DETERMINE THE EXTENT OF HEPATIC FIBROSIS, INCLUDING THE USE OF DIRECT AND INDIRECT BIOMARKERS. IMMEDIATE DIAGNOSIS OF HEPATIC FIBROSIS BY NONINVASIVE MEANS WOULD BE MORE PALATABLE THAN A BIOPSY AND COULD ASSIST CLINICIANS IN TAKING EARLY INTERVENTIONS TIMELY, AVOIDING FATAL COMPLICATIONS, AND IMPROVING PROGNOSIS. THEREFORE, WE SOUGHT TO REVIEW SOME COMMON BIOMARKERS OF LIVER FIBROSIS ALONG WITH SOME EMERGING CANDIDATES, INCLUDING THE OXIDATIVE STRESS-MEDIATED BIOMARKERS, EPIGENETIC AND GENETIC MARKERS, EXOSOMES, AND MIRNAS THAT NEEDS FURTHER EVALUATION AND WOULD HAVE BETTER SENSITIVITY AND SPECIFICITY. WE ALSO AIM TO ELUCIDATE THE POTENTIAL ROLE OF CARDIOTONIC STEROIDS (CTS) AND EVALUATE THE PRO-INFLAMMATORY AND PROFIBROTIC EFFECTS OF CTS IN EXACERBATING HEPATIC FIBROSIS. BY UNDERSTANDING THE UNDERLYING PATHOGENIC PROCESSES, THE EFFICACY OF THESE BIOMARKERS COULD ALLOW FOR EARLY DIAGNOSIS AND TREATMENT OF HEPATIC FIBROSIS IN CHRONIC LIVER DISEASES, ONCE VALIDATED. 2020 17 1491 35 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 18 3105 45 GENOMICS AND PROTEOMICS IN LIVER FIBROSIS AND CIRRHOSIS. GENOMICS AND PROTEOMICS HAVE BECOME INCREASINGLY IMPORTANT IN BIOMEDICAL SCIENCE IN THE PAST DECADE, AS THEY PROVIDE AN OPPORTUNITY FOR HYPOTHESIS-FREE EXPERIMENTS THAT CAN YIELD MAJOR INSIGHTS NOT PREVIOUSLY FORESEEN WHEN SCIENTIFIC AND CLINICAL QUESTIONS ARE BASED ONLY ON HYPOTHESIS-DRIVEN APPROACHES. USE OF THESE TOOLS, THEREFORE, OPENS NEW AVENUES FOR UNCOVERING PHYSIOLOGICAL AND PATHOLOGICAL PATHWAYS. LIVER FIBROSIS IS A COMPLEX DISEASE PROVOKED BY A RANGE OF CHRONIC INJURIES TO THE LIVER, AMONG WHICH ARE VIRAL HEPATITIS, (NON-) ALCOHOLIC STEATOHEPATITIS AND AUTOIMMUNE DISORDERS. SOME CHRONIC LIVER PATIENTS WILL NEVER DEVELOP FIBROSIS OR CIRRHOSIS, WHEREAS OTHERS RAPIDLY PROGRESS TOWARDS CIRRHOSIS IN A FEW YEARS. THIS VARIETY CAN BE CAUSED BY DISEASE-RELATED FACTORS (FOR EXAMPLE, VIRAL GENOTYPE) OR HOST-FACTORS (GENETIC/EPIGENETIC). IT IS VITAL TO ESTABLISH ACCURATE TOOLS TO IDENTIFY THOSE PATIENTS AT HIGHEST RISK FOR DISEASE SEVERITY OR PROGRESSION IN ORDER TO DETERMINE WHO ARE IN NEED OF IMMEDIATE THERAPIES. MOREOVER, THERE IS AN URGENT IMPERATIVE TO IDENTIFY NON-INVASIVE MARKERS THAT CAN ACCURATELY DISTINGUISH MILD AND INTERMEDIATE STAGES OF FIBROSIS. IDEALLY, BIOMARKERS CAN BE USED TO PREDICT DISEASE PROGRESSION AND TREATMENT RESPONSE, BUT THESE STUDIES WILL TAKE MANY YEARS DUE TO THE REQUIREMENT FOR LENGTHY FOLLOW-UP PERIODS TO ASSESS OUTCOMES. CURRENT GENOMIC AND PROTEOMIC RESEARCH PROVIDES MANY CANDIDATE BIOMARKERS, BUT INDEPENDENT VALIDATION OF THESE BIOMARKERS IS LACKING, AND REPRODUCIBILITY IS STILL A KEY CONCERN. THUS, GREAT OPPORTUNITIES AND CHALLENGES LIE AHEAD IN THE FIELD OF GENOMICS AND PROTEOMICS, WHICH, IF SUCCESSFUL, COULD TRANSFORM THE DIAGNOSIS AND TREATMENT OF CHRONIC FIBROSING LIVER DISEASES. 2012 19 6264 31 THE MULTIPLE-HIT PATHOGENESIS OF NON-ALCOHOLIC FATTY LIVER DISEASE (NAFLD). NONALCOHOLIC FATTY LIVER DISEASE (NAFLD) IS INCREASINGLY PREVALENT AND REPRESENTS A GROWING CHALLENGE IN TERMS OF PREVENTION AND TREATMENT. DESPITE ITS HIGH PREVALENCE, ONLY A SMALL MINORITY OF AFFECTED PATIENTS DEVELOPS INFLAMMATION AND SUBSEQUENTLY FIBROSIS AND CHRONIC LIVER DISEASE, WHILE MOST OF THEM ONLY EXHIBIT SIMPLE STEATOSIS. IN THIS CONTEXT, THE FULL UNDERSTANDING OF THE MECHANISMS UNDERLYING THE DEVELOPMENT OF NAFLD AND NON-ALCOHOLIC STEATOHEPATITIS (NASH) IS OF EXTREME IMPORTANCE; DESPITE ADVANCES IN THIS FIELD, KNOWLEDGE ON THE PATHOGENESIS OF NAFLD IS STILL INCOMPLETE. THE 'TWO-HIT' HYPOTHESIS IS NOW OBSOLETE, AS IT IS INADEQUATE TO EXPLAIN THE SEVERAL MOLECULAR AND METABOLIC CHANGES THAT TAKE PLACE IN NAFLD. THE "MULTIPLE HIT" HYPOTHESIS CONSIDERS MULTIPLE INSULTS ACTING TOGETHER ON GENETICALLY PREDISPOSED SUBJECTS TO INDUCE NAFLD AND PROVIDES A MORE ACCURATE EXPLANATION OF NAFLD PATHOGENESIS. SUCH HITS INCLUDE INSULIN RESISTANCE, HORMONES SECRETED FROM THE ADIPOSE TISSUE, NUTRITIONAL FACTORS, GUT MICROBIOTA AND GENETIC AND EPIGENETIC FACTORS. IN THIS ARTICLE, WE REVIEW THE FACTORS THAT FORM THIS HYPOTHESIS. 2016 20 2691 22 EVOLUTION OF HEPATIC FIBROSIS RESEARCH. MOLECULAR ANALYSIS OF HEPATIC FIBROGENESIS HAS PROGRESSED WITH RESPECT TO BOTH FIBROSIS PROGRESSION AND REGRESSION BY USING CELL BIOLOGICAL, MOLECULAR BIOLOGICAL AND (EPI)GENETIC APPROACHES. RECENT RESEARCHES HAVE REVEALED SOURCES OF COLLAGEN-PRODUCING CELLS OTHER THAN HEPATIC STELLATE CELLS IN THE LIVER, AND THE INVOLVEMENT OF THE INNATE IMMUNE SYSTEM AND OXIDATIVE STRESS IN THE FIBROTIC PROCESS HAS ATTRACTED NEW ATTENTION. TOGETHER WITH THESE ADVANCEMENTS IN BASIC KNOWLEDGE ON THE CELLULAR AND MOLECULAR BIOLOGY OF HEPATIC FIBROSIS, CLINICAL RESEARCHES HAVE LINKED THE CLARIFICATION OF THE RELATIONSHIP BETWEEN PROGRESSION OF THE FIBROSIS STAGE AND THERAPEUTIC EFFICACY FOR CHRONIC VIRAL HEPATITIS AND NON-ALCOHOLIC STEATOHEPATITIS AND VALIDATION OF THE REGRESSION OF ADVANCED FIBROSIS, EVEN CIRRHOSIS, OF APPROPRIATE THERAPIES USING MODERN MEDICINES. FURTHERMORE, NON-INVASIVE ASSESSMENT OF LIVER FIBROSIS USING AN ULTRASOUND-BASED MODALITY HAS BECOME A FOCUS IN THE CLINICAL DIAGNOSIS OF LIVER FIBROSIS INSTEAD OF LIVER BIOPSY. TAKEN TOGETHER, LIVER FIBROSIS RESEARCH HAS BEEN EVOLVING BOTH BASICALLY AND CLINICALLY IN THE PAST THREE DECADES. 2011