1 2954 129 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 2 1285 46 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 3 4710 28 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 4 3022 38 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 5 6900 33 [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 6 3293 36 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 2544 29 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 8 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 9 4314 37 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 1128 37 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 11 1491 34 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 12 2287 43 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 13 2570 33 EPIGENETICS OF CHRONIC INFLAMMATORY DISEASES. CHRONIC, NONCOMMUNICABLE, AND INFLAMMATION-ASSOCIATED DISEASES REMAIN THE LARGEST CAUSE OF MORBIDITY AND MORTALITY GLOBALLY AND WITHIN THE UNITED STATES. THIS IS MAINLY DUE TO OUR LIMITED UNDERSTANDING OF THE MOLECULAR MECHANISMS THAT UNDERLIE THESE COMPLEX PATHOLOGIES. THE AVAILABLE EVIDENCE INDICATES THAT STUDIES OF EPIGENETICS (TRADITIONALLY DEFINED AS THE HERITABLE CHANGES TO GENE EXPRESSION THAT ARE INDEPENDENT OF CHANGES TO DNA) ARE SIGNIFICANTLY ADVANCING OUR KNOWLEDGE OF THESE INFLAMMATORY CONDITIONS. THIS REVIEW WILL FOCUS ON EPIGENETIC STUDIES OF THREE DISEASES, THAT ARE AMONG THE MOST BURDENSOME GLOBALLY: CARDIOVASCULAR DISEASE, THE NUMBER ONE CAUSE OF DEATHS WORLDWIDE, TYPE 2 DIABETES AND, ALZHEIMER'S DISEASE. THE CURRENT STATUS OF EPIGENETIC RESEARCH, INCLUDING THE ABILITY TO PREDICT DISEASE RISK, AND KEY PATHOPHYSIOLOGICAL DEFECTS ARE DISCUSSED. THE SIGNIFICANCE OF DEFINING THE CONTRIBUTION OF EPIGENETIC DEFECTS TO NONRESOLVING INFLAMMATION AND AGING, EACH ASSOCIATED WITH THESE DISEASES, IS HIGHLIGHTED, AS THESE ARE LIKELY TO PROVIDE NEW INSIGHTS INTO INFLAMMATORY DISEASE PATHOGENESIS. 2019 14 6913 23 [VARIOUS PATHWAYS LEADING TO THE PROGRESSION OF CHRONIC LIVER DISEASES]. AS THE RESULT OF VARIOUS EFFECTS (VIRUSES, METABOLIC DISEASES, NUTRITIONAL FACTORS, TOXIC AGENTS, AUTOIMMUNE PROCESSES) ABNORMAL LIVER FUNCTION, LIVER STEATOSIS AND CONNECTIVE TISSUE REMODELING MAY DEVELOP. PROGRESSION OF THIS PROCESS IS COMPLEX INCLUDING VARIOUS PATHWAYS AND A NUMBER OF FACTORS. THE AUTHORS SUMMARIZE THE FACTORS INVOLVED IN THE PROGRESSION OF CHRONIC LIVER DISEASE. THEY DESCRIBE THE ROLE OF CELLS AND THE PRODUCED INFLAMMATORY MEDIATORS AND CYTOKINES, AS WELL AS THE RELATIONSHIP BETWEEN THE DISEASE AND THE INTESTINAL FLORA. THEY EMPHASIZE THE ROLE OF OXIDATIVE STRESS, MITOCHONDRIAL DYSFUNCTION AND CELL DEATH IN DISEASE PROGRESSION. INSULIN RESISTANCE AND MICRO-ELEMENTS (IRON, COPPER) IN RELATION TO LIVER DAMAGE ARE ALSO DISCUSSED, AND GENETIC AND EPIGENETIC ASPECTS UNDERLYING DISEASE PROGRESSION ARE SUMMARIZED. DISCOVERY OF NOVEL TREATMENT OPTIONS, ASSESSMENT OF THE EFFECTIVENESS OF TREATMENT, AS WELL AS THE SUCCESS AND PROPER TIMING OF LIVER TRANSPLANTATION MAY DEPEND ON A BETTER UNDERSTANDING OF THE PROCESS OF DISEASE PROGRESSION. 2016 15 1871 40 EMERGING ROLE OF EPIGENETICS IN EXPLAINING RELATIONSHIP OF PERIODONTITIS AND CARDIOVASCULAR DISEASES. CARDIOVASCULAR DISEASES SUCH AS ISCHEMIC HEART DISEASES OR STROKE ARE AMONG THE LEADING CAUSE OF DEATHS GLOBALLY, AND EVIDENCE SUGGESTS THAT THESE DISEASES ARE MODULATED BY A MULTIFACTORIAL AND COMPLEX INTERPLAY OF GENETIC, ENVIRONMENTAL, AND LIFESTYLE FACTORS. GENETIC PREDISPOSITION AND CHRONIC EXPOSURE TO MODIFIABLE RISK FACTORS HAVE BEEN EXPLORED TO BE INVOLVED IN THE PATHOPHYSIOLOGY OF CVD. ENVIRONMENTAL FACTORS CONTRIBUTE TO AN INDIVIDUAL'S PROPENSITY TO DEVELOP MAJOR CARDIOVASCULAR RISK FACTORS THROUGH EPIGENETIC MODIFICATIONS OF DNA AND HISTONES VIA MIRNA REGULATION OF PROTEIN TRANSLATION THAT ARE TYPES OF EPIGENETIC MECHANISMS AND PARTICIPATE IN DISEASE DEVELOPMENT. PERIODONTAL DISEASE (PD) IS ONE OF THE MOST COMMON ORAL DISEASES IN HUMANS THAT IS CHARACTERIZED BY LOW-GRADE INFLAMMATION AND HAS BEEN SHOWN TO INCREASE THE RISK OF CVDS. RISK FACTORS INVOLVED IN PD AND CVD ARE DETERMINED BOTH GENETICALLY AND BEHAVIORALLY. PERIODONTAL DISEASES SUCH AS CHRONIC INFLAMMATION PROMOTE DNA METHYLATION. EPIGENETIC MODIFICATIONS INVOLVED IN THE INITIATION AND PROGRESSION OF ATHEROSCLEROSIS PLAY AN ESSENTIAL ROLE IN PLAQUE DEVELOPMENT AND VULNERABILITY. EPIGENETICS HAS OPENED A NEW WORLD TO UNDERSTAND AND MANAGE HUMAN DISEASES, INCLUDING CVDS AND PERIODONTAL DISEASES. GENETIC MEDICINE HAS STARTED A NEW ERA OF EPIGENETICS TO OVERCOME HUMAN DISEASES WITH VARIOUS NEW METHODOLOGY. EPIGENETIC PROFILING MAY AID IN BETTER DIAGNOSIS AND STRATIFICATION OF PATIENTS SHOWING POTENTIAL PREDISPOSED STATES FOR DISEASE. A BETTER UNDERSTANDING OF THE EXACT REGULATORY MECHANISMS OF EPIGENETIC PATHWAYS DRIVING INFLAMMATION IS SLOWLY EMERGING AND WILL AID IN DEVELOPING NOVEL TOOLS FOR THE TREATMENT OF DISEASE. 2021 16 4325 33 MICRORNAS IN THE EVALUATION AND POTENTIAL TREATMENT OF LIVER DISEASES. ACUTE AND CHRONIC LIVER DISEASE CONTINUE TO RESULT IN SIGNIFICANT MORBIDITY AND MORTALITY OF PATIENTS, ALONG WITH INCREASING BURDEN ON THEIR FAMILIES, SOCIETY AND THE HEALTH CARE SYSTEM. THIS IN PART IS DUE TO INCREASED INCIDENCE OF LIVER DISEASE ASSOCIATED FACTORS SUCH AS METABOLIC SYNDROME; IMPROVED SURVIVAL OF PATIENTS WITH CHRONIC PREDISPOSING CONDITIONS SUCH AS HIV; AS WELL AS ADVANCES IN THE FIELD OF TRANSPLANTATION AND ASSOCIATED CARE LEADING TO IMPROVED SURVIVAL. THE FACT THAT ONE DISEASE CAN RESULT IN DIFFERENT MANIFESTATIONS AND OUTCOMES HIGHLIGHTS THE NEED FOR IMPROVED UNDERSTANDING OF NOT JUST GENETIC PHENOMENON PREDISPOSING TO A CONDITION, BUT ADDITIONALLY THE ROLE OF EPIGENETIC AND ENVIRONMENTAL FACTORS LEADING TO THE PHENOTYPE OF THE DISEASE. IT IS NOT SURPRISING THAT PROVIDERS CONTINUE TO FACE DAILY CHALLENGES PERTAINING TO DIAGNOSTIC ACCURACY, PROGNOSTICATION OF DISEASE SEVERITY, PROGRESSION, AND RESPONSE TO THERAPIES. A NUMBER OF THESE CHALLENGES CAN BE ADDRESSED BY INCORPORATING A PERSONALIZED APPROACH OF MANAGEMENT TO THE CURRENT PARADIGM OF CARE. RECENT ADVANCES IN THE FIELDS OF MOLECULAR BIOLOGY AND GENETICS HAVE PAVED THE WAY TO MORE ACCURATE, INDIVIDUALIZED AND PRECISE APPROACH TO CARING FOR LIVER DISEASE. THE STUDY OF MICRORNAS AND THEIR ROLE IN BOTH HEALTHY AND DISEASED LIVERS IS ONE EXAMPLE OF SUCH ADVANCES. AS THESE SMALL, NON-CODING RNAS WORK ON FINE-TUNING OF CELLULAR ACTIVITIES AND ORGAN FUNCTION IN A DYNAMIC AND PRECISE FASHION, THEY PROVIDE US A GOLDEN OPPORTUNITY TO ADVANCE THE FIELD OF HEPATOLOGY. THE STUDY OF MICRORNAS IN LIVER DISEASE PROMISES TREMENDOUS IMPROVEMENT IN HEPATOLOGY AND IS LIKELY TO LAY THE FOUNDATION TOWARDS A PERSONALIZED APPROACH IN LIVER DISEASE. 2016 17 3105 42 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 18 4722 40 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 19 394 37 AN UPDATE IN EPIGENETICS IN METABOLIC-ASSOCIATED FATTY LIVER DISEASE. METABOLIC-ASSOCIATED FATTY LIVER DISEASE (MAFLD) IS CHARACTERIZED BY HEPATIC STEATOSIS ACCOMPANIED BY ONE OF THREE FEATURES: OVERWEIGHT OR OBESITY, T2DM, OR LEAN OR NORMAL WEIGHT WITH EVIDENCE OF METABOLIC DYSREGULATION. IT IS DISTINGUISHED BY EXCESSIVE FAT ACCUMULATION IN HEPATOCYTES, AND A DECREASE IN THE LIVER'S ABILITY TO OXIDIZE FATS, THE ACCUMULATION OF ECTOPIC FAT, AND THE ACTIVATION OF PROINFLAMMATORY PATHWAYS. CHRONIC DAMAGE WILL KEEP THIS PATHOPHYSIOLOGIC CYCLE ACTIVE CAUSING PROGRESSION FROM HEPATIC STEATOSIS TO CIRRHOSIS AND EVENTUALLY, HEPATOCARCINOMA. EPIGENETICS AFFECTING GENE EXPRESSION WITHOUT ALTERING DNA SEQUENCE ALLOWS US TO STUDY MAFLD PATHOPHYSIOLOGY FROM A DIFFERENT PERSPECTIVE, IN WHICH DNA METHYLATION PROCESSES, HISTONE MODIFICATIONS, AND MIRNAS EXPRESSION HAVE BEEN CLOSELY ASSOCIATED WITH MAFLD PROGRESSION. HOWEVER, THESE CONSIDERATIONS ALSO FACED US WITH THE CIRCUMSTANCE THAT MODIFYING THOSE EPIGENETICS PATTERNS MIGHT LEAD TO MAFLD REGRESSION. CURRENTLY, EPIGENETICS IS AN AREA OF GREAT INTEREST BECAUSE IT COULD PROVIDE NEW INSIGHTS IN THERAPEUTIC TARGETS AND NON-INVASIVE BIOMARKERS. THIS REVIEW COMPRISES AN UPDATE ON THE ROLE OF EPIGENETIC PATTERNS, AS WELL AS INNOVATIVE THERAPEUTIC TARGETS AND BIOMARKERS IN MAFLD. 2021 20 5079 38 PHYSIOPATHOLOGY OF NONALCOHOLIC FATTY LIVER DISEASE: FROM DIET TO NUTRIGENOMICS. PURPOSE OF REVIEW: NONALCOHOLIC FATTY LIVER DISEASE (NAFLD) IS THE MOST COMMON CAUSE OF CHRONIC LIVER DISEASE WORLDWIDE AND IS STRONGLY ASSOCIATED WITH METABOLIC DISORDERS, SUCH AS OBESITY, TYPE 2 DIABETES MELLITUS, AND METABOLIC SYNDROME, TO THE EXTENT THAT A NEW DEFINITION OF METABOLIC ASSOCIATED FATTY LIVER DISEASE HAS BEEN PROPOSED. RECENT FINDINGS: INSULIN RESISTANCE, WORSENED BY A HIGH-FAT AND HIGH-CARBOHYDRATE DIET, IS THE KEY TO THE PHYSIOPATHOLOGY OF HEPATIC STEATOSIS. THIS IS DRIVEN BY SEVERAL MECHANISMS THAT ARE MOSTLY ACTIVATED AT A GENETIC LEVEL, SUCH AS DE-NOVO LIPOGENESIS AND TRIGLYCERIDE SYNTHESIS. THEREFORE, MANY DIET REGIMENS HAVE BEEN STUDIED, ALTHOUGH SIGNIFICANT CONTROVERSIES REMAIN REGARDING THEIR METABOLIC EFFECTS AND LONG-TERM SUSTAINABILITY. SUMMARY: IN THIS REVIEW, WE SUMMARIZED THE ROLE AND EFFECTS OF THE MAIN MACRONUTRIENTS ON THE DEVELOPMENT OF NAFLD AND DISCUSSED THE MOLECULAR MECHANISMS INVOLVED. WE ALSO DISCUSSED THE IMPORTANCE OF GENETIC POLYMORPHISMS, EPIGENETIC ALTERATIONS, AND DYSBIOSIS TO DETERMINE IF LIFESTYLE MODIFICATION AND A SPECIFIC DIETARY REGIMEN COULD BE AN ESSENTIAL PART OF NAFLD TREATMENT. 2022