1 3748 129 INSIGHTS INTO THE ROLE OF DNA METHYLATION AND PROTEIN MISFOLDING IN DIABETES MELLITUS. BACKGROUND: DIABETES MELLITUS IS A METABOLIC DISORDER THAT IS CHARACTERIZED BY IMPAIRED GLUCOSE TOLERANCE RESULTING FROM DEFECTS IN INSULIN SECRETION, INSULIN ACTION, OR BOTH. EPIGENETIC MODIFICATIONS, WHICH ARE DEFINED AS INHERITED CHANGES IN GENE EXPRESSION THAT OCCUR WITHOUT CHANGES IN GENE SEQUENCE, ARE INVOLVED IN THE ETIOLOGY OF DIABETES. METHODS: IN THIS REVIEW, WE FOCUSED ON THE ROLE OF DNA METHYLATION AND PROTEIN MISFOLDING AND THEIR CONTRIBUTION TO THE DEVELOPMENT OF BOTH TYPE 1 AND TYPE 2 DIABETES MELLITUS. RESULTS: CHANGES IN DNA METHYLATION IN PARTICULAR ARE HIGHLY ASSOCIATED WITH THE DEVELOPMENT OF DIABETES. PROTEIN FUNCTION IS DEPENDENT ON THEIR PROPER FOLDING IN THE ENDOPLASMIC RETICULUM. DEFECTIVE PROTEIN FOLDING AND CONSEQUENTLY THEIR FUNCTIONS HAVE ALSO BEEN REPORTED TO PLAY A ROLE. EARLY TREATMENT OF DIABETES HAS PROVEN TO BE OF GREAT BENEFIT, AS EVEN TRANSIENT HYPERGLYCEMIA MAY LEAD TO PATHOLOGICAL EFFECTS AND COMPLICATIONS LATER ON. THIS HAS BEEN EXPLAINED BY THE THEORY OF THE DEVELOPMENT OF A METABOLIC MEMORY IN DIABETES. THE BASIS FOR THIS METABOLIC MEMORY WAS ATTRIBUTED TO OXIDATIVE STRESS, CHRONIC INFLAMMATION, NON-ENZYMATIC GLYCATION OF PROTEINS AND IMPORTANTLY, EPIGENETIC CHANGES. THIS HIGHLIGHTS THE IMPORTANCE OF LINKING NEW THERAPEUTICS TARGETING EPIGENETIC MECHANISMS WITH TRADITIONAL ANTIDIABETIC DRUGS. CONCLUSION: ALTHOUGH NEW DATA IS EVOLVING ON THE RELATION BETWEEN DNA METHYLATION, PROTEIN MISFOLDING, AND THE ETIOLOGY OF DIABETES, MORE STUDIES ARE REQUIRED FOR DEVELOPING NEW RELEVANT DIAGNOSTICS AND THERAPEUTICS. 2019 2 2163 47 EPIGENETIC MECHANISMS IN DIABETIC VASCULAR COMPLICATIONS. THERE HAS BEEN A RAPID INCREASE IN THE INCIDENCE OF DIABETES AS WELL THE ASSOCIATED VASCULAR COMPLICATIONS. BOTH GENETIC AND ENVIRONMENTAL FACTORS HAVE BEEN IMPLICATED IN THESE PATHOLOGIES. INCREASING EVIDENCE SUGGESTS THAT EPIGENETIC FACTORS PLAY A KEY ROLE IN THE COMPLEX INTERPLAY BETWEEN GENES AND THE ENVIRONMENT. ACTIONS OF MAJOR PATHOLOGICAL MEDIATORS OF DIABETES AND ITS COMPLICATIONS SUCH AS HYPERGLYCAEMIA, OXIDANT STRESS, AND INFLAMMATORY FACTORS CAN LEAD TO DYSREGULATED EPIGENETIC MECHANISMS THAT AFFECT CHROMATIN STRUCTURE AND GENE EXPRESSION. FURTHERMORE, PERSISTENCE OF THIS ALTERED STATE OF THE EPIGENOME MAY BE THE UNDERLYING MECHANISM CONTRIBUTING TO A 'METABOLIC MEMORY' THAT RESULTS IN CHRONIC INFLAMMATION AND VASCULAR DYSFUNCTION IN DIABETES EVEN AFTER ACHIEVING GLYCAEMIC CONTROL. FURTHER EXAMINATION OF EPIGENETIC MECHANISMS BY ALSO TAKING ADVANTAGE OF RECENTLY DEVELOPED NEXT-GENERATION SEQUENCING TECHNOLOGIES CAN PROVIDE NOVEL INSIGHTS INTO THE PATHOLOGY OF DIABETES AND ITS COMPLICATIONS AND LEAD TO THE DISCOVERY OF MUCH NEEDED NEW DRUG TARGETS FOR THESE DISEASES. IN THIS REVIEW, WE HIGHLIGHT THE ROLE OF EPIGENETICS IN DIABETES AND ITS VASCULAR COMPLICATIONS, AND RECENT TECHNOLOGICAL ADVANCES THAT HAVE SIGNIFICANTLY ACCELERATED THE FIELD. 2011 3 2613 48 EPIGENETICS: DECIPHERING ITS ROLE IN DIABETES AND ITS CHRONIC COMPLICATIONS. 1. INCREASING EVIDENCE SUGGESTS THAT EPIGENETIC FACTORS MIGHT REGULATE THE COMPLEX INTERPLAY BETWEEN GENES AND THE ENVIRONMENT, AND AFFECT HUMAN DISEASES, SUCH AS DIABETES AND ITS COMPLICATIONS. 2. CLINICAL TRIALS HAVE UNDERSCORED THE LONG LASTING BENEFICIAL EFFECTS OF STRICT GLYCAEMIC CONTROL FOR REDUCING THE PROGRESSION OF DIABETIC COMPLICATIONS. THEY HAVE ALSO SHOWN THAT DIABETIC COMPLICATIONS, SUCH AS DIABETIC NEPHROPATHY, A CHRONIC KIDNEY DISORDER, CAN CONTINUE EVEN AFTER BLOOD GLUCOSE NORMALIZATION, SUGGESTING A METABOLIC MEMORY OF THE PRIOR GLYCAEMIC STATE. 3. DYSREGULATION OF EPIGENETIC POST-TRANSCRIPTIONAL MODIFICATIONS OF HISTONES IN CHROMATIN, INCLUDING HISTONE LYSINE METHYLATION, HAS BEEN IMPLICATED IN ABERRANT GENE REGULATION ASSOCIATED WITH THE PATHOLOGY OF DIABETES AND ITS COMPLICATIONS. GENOME-WIDE STUDIES HAVE SHOWN CELL-TYPE SPECIFIC CHANGES IN HISTONE METHYLATION PATTERNS UNDER DIABETIC CONDITIONS. IN ADDITION, STUDIES IN VASCULAR CELLS HAVE SHOWN LONG LASTING CHANGES IN EPIGENETIC MODIFICATIONS AT KEY INFLAMMATORY GENE PROMOTERS AFTER PRIOR EXPOSURE TO DIABETIC CONDITIONS, SUGGESTING A POSSIBLE MECHANISM FOR METABOLIC MEMORY. 4. RECENT STUDIES HAVE SHOWN ROLES FOR HISTONE METHYLATION, DNA METHYLATION, AS WELL AS MICRORNA IN DIABETIC NEPHROPATHY. WHETHER THESE EPIGENETIC FACTORS PLAY A ROLE IN METABOLIC MEMORY OF DIABETIC KIDNEY DISEASE IS LESS WELL UNDERSTOOD. 5. THE INCIDENCE OF DIABETES IS GROWING RAPIDLY, AS ALSO THE COST OF TREATING THE RESULTING COMPLICATIONS. A BETTER UNDERSTANDING OF METABOLIC MEMORY AND THE POTENTIAL INVOLVEMENT OF EPIGENETIC MECHANISMS IN THIS PHENOMENON COULD ENABLE THE DEVELOPMENT OF NEW THERAPEUTIC TARGETS FOR THE TREATMENT AND/OR PREVENTION OF SUSTAINED DIABETIC COMPLICATIONS. 2011 4 776 47 CELL- AND TISSUE-SPECIFIC EPIGENETIC CHANGES ASSOCIATED WITH CHRONIC INFLAMMATION IN INSULIN RESISTANCE AND TYPE 2 DIABETES MELLITUS. TYPE 2 DIABETES MELLITUS (T2DM) IS A CHRONIC METABOLIC DISORDER CHARACTERIZED BY HYPERGLYCAEMIA, WHICH CAN CAUSE MICRO- AND MACROVASCULAR COMPLICATIONS. CHRONIC INFLAMMATION MAY BE THE CAUSE AND RESULT OF T2DM, AND ITS RELATED COMPLICATIONS AS AN IMBALANCE BETWEEN PRO- AND ANTI-INFLAMMATORY CYTOKINES CAN AFFECT IMMUNE FUNCTIONS. APART FROM GENETIC CHANGES OCCURRING WITHIN THE BODY RESULTING IN INFLAMMATION IN T2DM, EPIGENETIC MODIFICATIONS CAN MODIFY GENE EXPRESSION IN RESPONSE TO ENVIRONMENTAL CUES SUCH AS AN UNHEALTHY DIET, LACK OF EXERCISE AND OBESITY. THE MOST WIDELY STUDIED EPIGENETIC MODIFICATION, DNA METHYLATION (DNAM), REGULATES GENE EXPRESSION AND MAY MANIPULATE INFLAMMATORY GENES TO INCREASE OR DECREASE INFLAMMATION ASSOCIATED WITH T2DM. THIS REVIEW EXPLORES THE STUDIES RELATED TO EPIGENETIC CHANGES, MORE SPECIFICALLY DNAM, ASSOCIATED WITH CHRONIC INFLAMMATION IN T2DM, AT BOTH THE CELL AND TISSUE LEVELS. STUDYING EPIGENETIC ALTERATIONS DURING INFLAMMATORY RESPONSE, AS A RESULT OF GENETIC AND ENVIRONMENTAL SIGNALS, CREATES OPPORTUNITIES FOR THE DEVELOPMENT OF "EARLY DETECTION/RELATIVE RISK" TESTS TO AID IN PREVENTION OF T2DM. UNDERSTANDING INFLAMMATION IN T2DM AT THE GENE LEVEL IN INFLAMMATION-ASSOCIATED CELLS AND TISSUES MAY PROVIDE FURTHER INSIGHT FOR THE DEVELOPMENT OF SPECIFIC THERAPEUTIC TARGETS FOR THE DISORDER. 2018 5 6067 55 THE DIABETES MELLITUS-ATHEROSCLEROSIS CONNECTION: THE ROLE OF LIPID AND GLUCOSE METABOLISM AND CHRONIC INFLAMMATION. DIABETES MELLITUS COMPRISES A GROUP OF CARBOHYDRATE METABOLISM DISORDERS THAT SHARE A COMMON MAIN FEATURE OF CHRONIC HYPERGLYCEMIA THAT RESULTS FROM DEFECTS OF INSULIN SECRETION, INSULIN ACTION, OR BOTH. INSULIN IS AN IMPORTANT ANABOLIC HORMONE, AND ITS DEFICIENCY LEADS TO VARIOUS METABOLIC ABNORMALITIES IN PROTEINS, LIPIDS, AND CARBOHYDRATES. ATHEROSCLEROSIS DEVELOPS AS A RESULT OF A MULTISTEP PROCESS ULTIMATELY LEADING TO CARDIOVASCULAR DISEASE ASSOCIATED WITH HIGH MORBIDITY AND MORTALITY. ALTERATION OF LIPID METABOLISM IS A RISK FACTOR AND CHARACTERISTIC FEATURE OF ATHEROSCLEROSIS. POSSIBLE LINKS BETWEEN THE TWO CHRONIC DISORDERS DEPENDING ON ALTERED METABOLIC PATHWAYS HAVE BEEN INVESTIGATED IN NUMEROUS STUDIES. IT WAS SHOWN THAT BOTH TYPES OF DIABETES MELLITUS CAN ACTUALLY INDUCE ATHEROSCLEROSIS DEVELOPMENT OR FURTHER ACCELERATE ITS PROGRESSION. ELEVATED GLUCOSE LEVEL, DYSLIPIDEMIA, AND OTHER METABOLIC ALTERATIONS THAT ACCOMPANY THE DISEASE DEVELOPMENT ARE TIGHTLY INVOLVED IN THE PATHOGENESIS OF ATHEROSCLEROSIS AT ALMOST EVERY STEP OF THE ATHEROGENIC PROCESS. CHRONIC INFLAMMATION IS CURRENTLY CONSIDERED AS ONE OF THE KEY FACTORS IN ATHEROSCLEROSIS DEVELOPMENT AND IS PRESENT STARTING FROM THE EARLIEST STAGES OF THE PATHOLOGY INITIATION. IT MAY ALSO BE REGARDED AS ONE OF THE POSSIBLE LINKS BETWEEN ATHEROSCLEROSIS AND DIABETES MELLITUS. HOWEVER, THE DATA AVAILABLE SO FAR DO NOT ALLOW FOR DEVELOPING EFFECTIVE ANTI-INFLAMMATORY THERAPEUTIC STRATEGIES THAT WOULD STOP ATHEROSCLEROTIC LESION PROGRESSION OR INDUCE LESION REDUCTION. IN THIS REVIEW, WE SUMMARIZE THE MAIN ASPECTS OF DIABETES MELLITUS THAT POSSIBLY AFFECT THE ATHEROGENIC PROCESS AND ITS RELATIONSHIP WITH CHRONIC INFLAMMATION. WE ALSO DISCUSS THE ESTABLISHED PATHOPHYSIOLOGICAL FEATURES THAT LINK ATHEROSCLEROSIS AND DIABETES MELLITUS, SUCH AS OXIDATIVE STRESS, ALTERED PROTEIN KINASE SIGNALING, AND THE ROLE OF CERTAIN MIRNA AND EPIGENETIC MODIFICATIONS. 2020 6 2190 50 EPIGENETIC MECHANISMS. THE INCIDENCE OF DIABETES AND RELATED COMPLICATIONS LIKE NEPHROPATHY IS GROWING RAPIDLY AND HAS BECOME A MAJOR HEALTH CARE ISSUE. CHANGES IN THE ENVIRONMENT AND NUTRITIONAL HABITS HAVE BEEN IMPLICATED AS MAJOR PLAYERS. FURTHERMORE, IT IS BECOMING INCREASINGLY CLEAR THAT EPIGENETIC FACTORS MAY MODULATE THE CONNECTIONS BETWEEN GENES AND THE ENVIRONMENT. WHILE DIABETES IN ITSELF IS TREATABLE TO A LARGE EXTENT, IT IS STILL ASSOCIATED WITH SIGNIFICANTLY INCREASED RISK FOR COMPLICATIONS INCLUDING CHRONIC KIDNEY AND CARDIOVASCULAR DISEASES. CURRENT TREATMENTS HAVE ADDED PREVENTATIVE APPROACHES SO AS TO AVOID FUTURE DIABETIC COMPLICATIONS. UNFORTUNATELY, DIABETIC PATIENTS ARE OFTEN PLAGUED WITH THE CONTINUED DEVELOPMENT OF VARIOUS COMPLICATIONS EVEN AFTER ACHIEVING GLUCOSE CONTROL. THIS HAS BEEN SUGGESTED TO BE ATTRIBUTABLE TO A MYSTERIOUS PHENOMENON TERMED 'METABOLIC MEMORY' OF THE PRIOR GLYCEMIC STATE. RECENT STUDIES HAVE SUGGESTED THAT EPIGENETIC CHANGES TO CHROMATIN CAN AFFECT GENE EXPRESSION IN RESPONSE TO VARIOUS STIMULI, AND CHANGES IN KEY BIOCHEMICAL PATHWAYS AND EPIGENETIC HISTONE AND DNA METHYLATION PATTERNS IN CHROMATIN HAVE BEEN OBSERVED IN A DIABETIC MILIEU. THESE ACCUMULATING DATA SUGGEST THAT METABOLIC OR HYPERGLYCEMIC MEMORY MAY BE DUE TO EPIGENETIC CHANGES IN SPECIFIC TARGET TISSUES ALTERING GENE EXPRESSION WITHOUT CHANGING THE GENETIC CODE ITSELF. WHILE THE GENETICS OF DIABETES HAS LONG BEEN THE FOCUS OF SCIENTIFIC RESEARCH, MUCH LESS IS KNOWN ABOUT THE ROLE OF EPIGENETICS AND THE RELATED MOLECULAR PATHWAYS THAT MIGHT AFFECT THE DEVELOPMENT OF DIABETES AND THE ASSOCIATED COMPLICATIONS. FURTHER STUDIES OF EPIGENETIC MECHANISMS ARE THEREFORE TIMELY AND COULD PROVIDE VALUABLE NEW INSIGHTS INTO THE PATHOLOGY OF DIABETIC COMPLICATIONS AND ALSO UNCOVER MUCH NEEDED NEW THERAPEUTIC TARGETS. 2011 7 6812 41 [EPIGENETICS, INTERFACE BETWEEN ENVIRONMENT AND GENES: ROLE IN COMPLEX DISEASES]. EPIGENETICS IS THE STUDY OF HERITABLE CHANGES IN GENE EXPRESSION OR CELLULAR PHENOTYPE CAUSED BY MECHANISMS OTHER THAN CHANGES IN THE UNDERLYING DNA SEQUENCE. EPIGENETICS IS ONE OF THE MAJOR MECHANISMS EXPLAINING THE "DEVELOPMENTAL ORIGIN OF HEALTH AND DISEASES" (DOHAD). BESIDES GENETIC BACKGROUND INHERITED FROM PARENTS, WHICH CONFERS SUSCEPTIBILITY TO CERTAIN PATHOLOGIES, EPIGENETIC CHANGES CONSTITUTE THE MEMORY OF PREVIOUS EVENTS, EITHER POSITIVE OR NEGATIVE, ALONG THE LIFE CYCLE, INCLUDING AT THE IN UTERO STAGE. THE LATER EXPOSITION TO HOSTILE ENVIRONMENT MAY REVEAL SUCH SUSCEPTIBILITY, WITH THE DEVELOPMENT OF VARIOUS PATHOLOGIES, AMONG THEM NUMEROUS CHRONIC COMPLEX DISEASES. THE DEMONSTRATION OF SUCH A SEQUENCE OF EVENTS HAS BEEN SHOWN FOR METABOLIC DISEASES AS OBESITY, METABOLIC SYNDROME AND TYPE 2 DIABETES, CARDIOVASCULAR DISEASE AND CANCER. IN CONTRAST TO GENETIC PREDISPOSITION, WHICH IS IRREVERSIBLE, EPIGENETIC CHANGES ARE POTENTIALLY REVERSIBLE, THUS GIVING TARGETS NOT ONLY FOR PREVENTION, BUT POSSIBLY ALSO FOR THE TREATMENT OF CERTAIN COMPLEX DISEASES. 2012 8 2491 41 EPIGENETICS AND CARDIOVASCULAR DISEASE IN DIABETES. TYPE 2 DIABETES HAS BECOME A MAJOR HEALTH ISSUE WORLDWIDE. CHRONIC HYPERGLYCEMIA INDUCES A LOW-GRADE INFLAMMATION THAT, ON TOP OF OTHER MECHANISMS, LEADS TO ENDOTHELIAL DYSFUNCTION. MOUNTING EVIDENCE SUGGESTS THAT DNA METHYLATION, POST-TRANSLATIONAL MODIFICATIONS OF HISTONES, AND LONG NON-CODING RNAS PLAY AN IMPORTANT ROLE IN THE INITIATION, MAINTENANCE, AND PROGRESSION OF BOTH MACRO- AND MICRO-VASCULAR COMPLICATIONS OF DIABETES. LONG-TERM EXPOSURE TO HYPERGLYCEMIA INDUCES EPIGENETIC CHANGES THAT COULD BECOME IRREVERSIBLE, A PHENOMENON KNOWN AS THE 'METABOLIC MEMORY.' WHETHER EPIGENETIC-BASED THERAPIES COULD BE USED TO SLOW OR LIMIT THE PROGRESSION OF CARDIOVASCULAR DISEASE REMAINS UNCLEAR. WHILE NON-CODING RNAS ARE CURRENTLY INVESTIGATED AS POTENTIAL BIOMARKERS THAT PREDICT DIABETIC CARDIOVASCULAR DISEASE INCIDENCE AND PROGRESSION, THEIR THERAPEUTIC ROLE IS ONLY HYPOTHETICAL. IN THIS REVIEW, WE HIGHLIGHT THE LATEST FINDINGS IN EXPERIMENTAL AND CLINICAL STUDIES RELEVANT TO EPIGENETICS AND CARDIOVASCULAR DISEASE IN DIABETES. 2015 9 4273 40 MICROBIOTA AND EPIGENETICS: HEALTH IMPACT. EPIGENETIC CHANGES ASSOCIATED WITH DISEASE DEVELOPMENT AND PROGRESSIONS ARE OF INCREASING IMPORTANCE BECAUSE OF THEIR POTENTIAL DIAGNOSTIC AND THERAPEUTIC APPLICATIONS. SEVERAL EPIGENETIC CHANGES ASSOCIATED WITH CHRONIC METABOLIC DISORDERS HAVE BEEN STUDIED IN VARIOUS DISEASES. EPIGENETIC CHANGES ARE MOSTLY MODULATED BY ENVIRONMENTAL FACTORS, INCLUDING THE HUMAN MICROBIOTA LIVING IN DIFFERENT PARTS OF OUR BODIES. THE MICROBIAL STRUCTURAL COMPONENTS AND THE MICROBIALLY DERIVED METABOLITES DIRECTLY INTERACT WITH HOST CELLS, THEREBY MAINTAINING HOMEOSTASIS. MICROBIOME DYSBIOSIS, ON THE OTHER HAND, IS KNOWN TO PRODUCE ELEVATED LEVELS OF DISEASE-LINKED METABOLITES, WHICH MAY DIRECTLY AFFECT A HOST METABOLIC PATHWAY OR INDUCE EPIGENETIC CHANGES THAT CAN LEAD TO DISEASE DEVELOPMENT. DESPITE THEIR IMPORTANT ROLE IN HOST PHYSIOLOGY AND SIGNAL TRANSDUCTION, THERE HAS BEEN LITTLE RESEARCH INTO THE MECHANICS AND PATHWAYS ASSOCIATED WITH EPIGENETIC MODIFICATIONS. THIS CHAPTER FOCUSES ON THE RELATIONSHIP BETWEEN MICROBES AND THEIR EPIGENETIC EFFECTS IN DISEASED PATHOLOGY, AS WELL AS ON THE REGULATION AND METABOLISM OF THE DIETARY OPTIONS AVAILABLE TO THE MICROBES. FURTHERMORE, THIS CHAPTER ALSO PROVIDES A PROSPECTIVE LINK BETWEEN THESE TWO IMPORTANT PHENOMENA, TERMED "MICROBIOME AND EPIGENETICS." 2023 10 5821 44 STRESS IN OBESITY AND ASSOCIATED METABOLIC AND CARDIOVASCULAR DISORDERS. OBESITY HAS SIGNIFICANT IMPLICATIONS FOR HEALTHCARE, SINCE IT IS A MAJOR RISK FACTOR FOR BOTH TYPE 2 DIABETES AND THE METABOLIC SYNDROME. THIS SYNDROME IS A COMMON AND COMPLEX DISORDER COMBINING OBESITY, DYSLIPIDEMIA, HYPERTENSION, AND INSULIN RESISTANCE. IT IS ASSOCIATED WITH HIGH ATHEROSCLEROTIC CARDIOVASCULAR RISK, WHICH CAN ONLY PARTIALLY BE EXPLAINED BY ITS COMPONENTS. THEREFORE, TO EXPLAIN HOW OBESITY CONTRIBUTES TO THE DEVELOPMENT OF METABOLIC AND CARDIOVASCULAR DISORDERS, MORE AND BETTER INSIGHT IS REQUIRED INTO THE EFFECTS OF PERSONAL AND ENVIRONMENTAL STRESS ON DISEASE PROCESSES. IN THIS PAPER, WE SHOW THAT OBESITY IS A CHRONIC INFLAMMATORY DISEASE, WHICH HAS MANY MOLECULAR MECHANISMS IN COMMON WITH ATHEROSCLEROSIS. FURTHERMORE, WE FOCUS ON THE ROLE OF OXIDATIVE STRESS ASSOCIATED WITH OBESITY IN THE DEVELOPMENT OF THE METABOLIC SYNDROME. WE DISCUSS HOW SEVERAL STRESS CONDITIONS ARE RELATED TO INFLAMMATION AND OXIDATIVE STRESS IN ASSOCIATION WITH OBESITY AND ITS COMPLICATIONS. WE ALSO EMPHASIZE THE RELATION BETWEEN STRESS CONDITIONS AND THE DEREGULATION OF EPIGENETIC CONTROL MECHANISMS BY MEANS OF MICRORNAS AND SHOW HOW THIS IMPAIRMENT FURTHER CONTRIBUTES TO THE DEVELOPMENT OF OBESITY, CLOSING THE VICIOUS CIRCLE. FINALLY, WE DISCUSS THE LIMITATIONS OF CURRENT ANTI-INFLAMMATION AND ANTIOXIDANT THERAPY TO TREAT OBESITY. 2012 11 4425 51 MOLECULAR BASIS OF AGEING IN CHRONIC METABOLIC DISEASES. AIM: OVER THE LAST DECADES, THE SHIFT IN AGE DISTRIBUTION TOWARDS OLDER AGES AND THE PROGRESSIVE AGEING WHICH HAS OCCURRED IN MOST POPULATIONS HAVE BEEN PARALLELED BY A GLOBAL EPIDEMIC OF OBESITY AND ITS RELATED METABOLIC DISORDERS, PRIMARILY, TYPE 2 DIABETES (T2D). DYSFUNCTION OF THE ADIPOSE TISSUE (AT) IS WIDELY RECOGNIZED AS A SIGNIFICANT HALLMARK OF THE AGEING PROCESS THAT, IN TURN, RESULTS IN SYSTEMIC METABOLIC ALTERATIONS. THESE INCLUDE INSULIN RESISTANCE, ACCUMULATION OF ECTOPIC LIPIDS AND CHRONIC INFLAMMATION, WHICH ARE RESPONSIBLE FOR AN ELEVATED RISK OF OBESITY AND T2D ONSET ASSOCIATED TO AGEING. ON THE OTHER HAND, OBESITY AND T2D, THE PARADIGMS OF AT DYSFUNCTION, SHARE MANY PHYSIOLOGICAL CHARACTERISTICS WITH THE AGEING PROCESS, SUCH AS AN INCREASED BURDEN OF SENESCENT CELLS AND EPIGENETIC ALTERATIONS. THUS, THESE CHRONIC METABOLIC DISORDERS MAY REPRESENT A STATE OF ACCELERATED AGEING. MATERIALS AND METHODS: A MORE PRECISE EXPLANATION OF THE FUNDAMENTAL AGEING MECHANISMS THAT OCCUR IN AT AND A DEEPER UNDERSTANDING OF THEIR ROLE IN THE INTERPLAY BETWEEN ACCELERATED AGEING AND AT DYSFUNCTION CAN BE A FUNDAMENTAL LEAP TOWARDS NOVEL THERAPIES THAT ADDRESS THE CAUSES, NOT JUST THE SYMPTOMS, OF OBESITY AND T2D, UTILIZING STRATEGIES THAT TARGET EITHER SENESCENT CELLS OR DNA METHYLATION. RESULTS: IN THIS REVIEW, WE SUMMARIZE THE CURRENT KNOWLEDGE OF THE PATHWAYS THAT LEAD TO AT DYSFUNCTION IN THE CHRONOLOGICAL AGEING PROCESS AS WELL AS THE PATHOPHYSIOLOGY OF OBESITY AND T2D, EMPHASIZING THE CRITICAL ROLE OF CELLULAR SENESCENCE AND DNA METHYLATION. CONCLUSION: FINALLY, WE HIGHLIGHT THE NEED FOR FURTHER RESEARCH FOCUSED ON TARGETING THESE MECHANISMS. 2020 12 6341 36 THE ROLE OF EPIGENETIC MODIFICATIONS IN LATE COMPLICATIONS IN TYPE 1 DIABETES. TYPE 1 DIABETES IS A CHRONIC AUTOIMMUNE DISEASE IN WHICH THE DESTRUCTION OF PANCREATIC BETA CELLS LEADS TO HYPERGLYCEMIA. THE PREVENTION OF HYPERGLYCEMIA IS VERY IMPORTANT TO AVOID OR AT LEAST POSTPONE THE DEVELOPMENT OF MICRO- AND MACROVASCULAR COMPLICATIONS, ALSO KNOWN AS LATE COMPLICATIONS. THESE INCLUDE DIABETIC RETINOPATHY, CHRONIC RENAL FAILURE, DIABETIC NEUROPATHY, AND CARDIOVASCULAR DISEASES. THE IMPACT OF LONG-TERM HYPERGLYCEMIA HAS BEEN SHOWN TO PERSIST LONG AFTER THE NORMALIZATION OF BLOOD GLUCOSE LEVELS, A PHENOMENON KNOWN AS METABOLIC MEMORY. IT IS BELIEVED THAT EPIGENETIC MECHANISMS SUCH AS DNA METHYLATION, HISTONE MODIFICATIONS, AND MICRORNAS, PLAY AN IMPORTANT ROLE IN METABOLIC MEMORY. THE AIM OF THIS REVIEW IS TO ADDRESS THE IMPACT OF LONG-TERM HYPERGLYCEMIA ON EPIGENETIC MARKS IN LATE COMPLICATIONS OF TYPE 1 DIABETES. 2022 13 2028 34 EPIGENETIC CHANGES IN DIABETES. DIABETES IS A MULTIFACTORIAL DISEASE WITH NUMEROUS PATHWAYS INFLUENCING ITS PROGRESSION AND RECENT OBSERVATIONS SUGGEST THAT THE COMPLEXITY OF THE DISEASE CANNOT BE ENTIRELY ACCOUNTED FOR BY GENETIC PREDISPOSITION. A COMPELLING ARGUMENT FOR AN EPIGENETIC COMPONENT IS RAPIDLY EMERGING. EPIGENETIC PROCESSES AT THE CHROMATIN TEMPLATE SIGNIFICANTLY SENSITIZE TRANSCRIPTIONAL AND PHENOTYPIC OUTCOMES TO ENVIRONMENTAL SIGNALING INFORMATION INCLUDING METABOLIC STATE, NUTRITIONAL REQUIREMENTS AND HISTORY. EPIGENETIC MECHANISMS IMPACT GENE EXPRESSION THAT COULD PREDISPOSE INDIVIDUALS TO THE DIABETIC PHENOTYPE DURING INTRAUTERINE AND EARLY POSTNATAL DEVELOPMENT, AS WELL AS THROUGHOUT ADULT LIFE. FURTHERMORE, EPIGENETIC CHANGES COULD ACCOUNT FOR THE ACCELERATED RATES OF CHRONIC AND PERSISTENT MICROVASCULAR AND MACROVASCULAR COMPLICATIONS ASSOCIATED WITH DIABETES. EPIDEMIOLOGICAL AND EXPERIMENTAL ANIMAL STUDIES IDENTIFIED POOR GLYCEMIC CONTROL AS A MAJOR CONTRIBUTOR TO THE DEVELOPMENT OF DIABETIC COMPLICATIONS AND HIGHLIGHT THE REQUIREMENT FOR EARLY INTERVENTION. EARLY EXPOSURE TO HYPERGLYCEMIA CAN DRIVE THE DEVELOPMENT OF COMPLICATIONS THAT MANIFEST LATE IN THE PROGRESSION OF THE DISEASE AND PERSIST DESPITE IMPROVED GLYCEMIC CONTROL, INDICATING A MEMORY OF THE METABOLIC INSULT. UNDERSTANDING THE MOLECULAR EVENTS THAT UNDERLIE THESE TRANSCRIPTIONAL CHANGES WILL SIGNIFICANTLY CONTRIBUTE TO NOVEL THERAPEUTIC INTERVENTIONS TO PREVENT, REVERSE OR RETARD THE DELETERIOUS EFFECTS OF THE DIABETIC MILIEU. 2013 14 3749 42 INSIGHTS INTO THE ROLE OF PLASMATIC AND EXOSOMAL MICRORNAS IN OXIDATIVE STRESS-RELATED METABOLIC DISEASES. A COMMON DENOMINATOR OF METABOLIC DISEASES, INCLUDING TYPE 2 DIABETES MELLITUS, DYSLIPIDEMIA, AND ATHEROSCLEROSIS, ARE ELEVATED OXIDATIVE STRESS AND CHRONIC INFLAMMATION. THESE COMPLEX, MULTI-FACTORIAL DISEASES ARE CAUSED BY THE DETRIMENTAL INTERACTION BETWEEN THE INDIVIDUAL GENETIC BACKGROUND AND MULTIPLE ENVIRONMENTAL STIMULI. THE CELLS, INCLUDING THE ENDOTHELIAL ONES, ACQUIRE A PREACTIVATED PHENOTYPE AND METABOLIC MEMORY, EXHIBITING INCREASED OXIDATIVE STRESS, INFLAMMATORY GENE EXPRESSION, ENDOTHELIAL VASCULAR ACTIVATION, AND PROTHROMBOTIC EVENTS, LEADING TO VASCULAR COMPLICATIONS. THERE ARE DIFFERENT PATHWAYS INVOLVED IN THE PATHOGENESIS OF METABOLIC DISEASES, AND INCREASED KNOWLEDGE SUGGESTS A ROLE OF THE ACTIVATION OF THE NF-KB PATHWAY AND NLRP3 INFLAMMASOME AS KEY MEDIATORS OF METABOLIC INFLAMMATION. EPIGENETIC-WIDE ASSOCIATED STUDIES PROVIDE NEW INSIGHT INTO THE ROLE OF MICRORNAS IN THE PHENOMENON OF METABOLIC MEMORY AND THE DEVELOPMENT CONSEQUENCES OF VESSEL DAMAGE. IN THIS REVIEW, WE WILL FOCUS ON THE MICRORNAS RELATED TO THE CONTROL OF ANTI-OXIDATIVE ENZYMES, AS WELL AS MICRORNAS RELATED TO THE CONTROL OF MITOCHONDRIAL FUNCTIONS AND INFLAMMATION. THE OBJECTIVE IS THE SEARCH FOR NEW THERAPEUTIC TARGETS TO IMPROVE THE FUNCTIONING OF MITOCHONDRIA AND REDUCE OXIDATIVE STRESS AND INFLAMMATION, DESPITE THE ACQUIRED METABOLIC MEMORY. 2023 15 1974 42 EPIGENETIC ALTERATIONS CAUSED BY NUTRITIONAL STRESS DURING FETAL PROGRAMMING OF THE ENDOCRINE PANCREAS. NUTRITION DURING CRITICAL PERIODS OF DEVELOPMENT IS ONE OF THE PIVOTAL FACTORS IN ESTABLISHING A LIFELONG HEALTHY METABOLISM. DIFFERENT NUTRITIONAL DEFICIENCIES SUCH AS A LOW AVAILABILITY OF PROTEINS IN THE MATERNAL DIET PRODUCE ALTERATIONS IN OFFSPRING THAT INCLUDE CHANGES IN INSULIN AND GLUCOSE METABOLISM, A DECREASE IN THE SIZE AND NUMBER OF CELLS OF PANCREATIC ISLETS OF LANGERHANS, AND PREMATURE AGEING OF THE SECRETORY FUNCTION OF PANCREATIC BETA CELLS. MOREOVER, IT HAS BEEN REPORTED THAT CHRONIC NUTRITIONAL STRESS IS ASSOCIATED WITH EPIGENETIC ALTERATIONS IN MECHANISMS OF GENE REGULATION DURING PANCREATIC DEVELOPMENT AND FUNCTION. THESE ALTERATIONS CAN LEAD TO DYSFUNCTIONAL STATES IN PANCREATIC BETA CELLS, WHICH IN THE LONG RUN ARE RESPONSIBLE FOR THE ONSET OF METABOLIC DISEASES LIKE TYPE 2 DIABETES. THE PRESENT REVIEW SUMMARIZES THE MOST IMPORTANT EVIDENCE IN RELATION TO THE PARTICIPATION OF EPIGENETIC MECHANISMS IN THE REGULATION OF GENE EXPRESSION DURING THE INTRAUTERINE PROGRAMMING OF THE ENDOCRINE PANCREAS IN ANIMAL MODELS. SUCH MECHANISMS INCLUDE DNA METHYLATION AS WELL AS MODIFICATIONS OF HISTONES AND MICRORNAS (MIRNAS). 2015 16 2154 45 EPIGENETIC MECHANISMS AND KIDNEY DISEASES. IN RECENT YEARS, MOLECULAR RESEARCH HAS BROUGHT TO LIGHT A SERIES OF MECHANISMS INVOLVED IN THE REGULATION OF GENE FUNCTION WITHOUT ALTERING THE DNA SEQUENCE. THESE MECHANISMS ARE DESCRIBED WITH THE TERM "EPIGENETICS" AND INCLUDE MODIFICATIONS IN THE STRUCTURE OF THE HUMAN GENOME, LEADING TO HERITABLE AND POTENTIALLY REVERSIBLE CHANGES IN GENE EXPRESSION. THERE IS NOW INCREASING EVIDENCE SUGGESTING THAT SEVERAL CHARACTERISTIC FEATURES OF CHRONIC KIDNEY DISEASE SUCH AS HYPERHOMOCYSTEINEMIA, SUBCLINICAL INFLAMMATION, INCREASED OXIDATIVE STRESS AND OTHERS MAY AFFECT THE HUMAN EPIGENOME. IN ADDITION, ANIMAL STUDIES HAVE SUGGESTED A POSSIBLE LINK BETWEEN NUTRITION AND ENVIRONMENTAL EXPOSURE DURING THE PERICONCEPTIONAL PERIOD AND EPIGENETIC CHANGES IN THE EXPRESSION OF MAJOR GENES IMPLICATED IN KIDNEY ORGANOGENESIS; THESE CHANGES RESULT IN A DIMINISHED NUMBER OF NEPHRONS IN THE DEVELOPING KIDNEY, WHICH PREDISPOSES TO AN INCREASED RISK FOR HYPERTENSION AND CHRONIC KIDNEY DISEASE IN FUTURE LIFE. THE UNDERSTANDING OF THE ROLE OF EPIGENETIC PHENOMENA IN THE PATHOGENESIS OF CHRONIC KIDNEY DISEASE OPENS NEW AVENUES FOR FUTURE THERAPEUTIC STRATEGIES, THROUGH THE DEVELOPMENT OF PHARMACEUTICAL AGENTS THAT TARGET DIRECTLY WITH THE CHANGES IN THE HUMAN EPIGENOME. SUCH EPIGENETIC DRUGS ARE ALREADY IN CLINICAL USE FOR THE TREATMENT OF CANCER AS WELL AS UNDER INVESTIGATION FOR THE USE IN OTHER DISEASES. THIS REVIEW WILL SUMMARIZE THE EXISTING DATA ON THE LINK BETWEEN EPIGENETIC MECHANISMS AND CHRONIC UREMIC MILIEU, AS WELL AS THE PROMISING RESULTS OF ONGOING RESEARCH IN THE FIELD OF EPIGENETIC DRUGS THAT COULD REPRESENT ADDITIONAL OPTIONS IN OUR THERAPEUTIC ARMAMENTARIUM FOR PATIENTS WITH CHRONIC KIDNEY DISEASE. 2011 17 2333 37 EPIGENETIC REGULATION OF INFLAMMATION: THE METABOLOMICS CONNECTION. EPIGENETIC FACTORS ARE CONSIDERED THE REGULATOR OF COMPLEX MACHINERY BEHIND INFLAMMATORY DISORDERS AND SIGNIFICANTLY CONTRIBUTED TO THE EXPRESSION OF INFLAMMATION-ASSOCIATED GENES. EPIGENETIC MODIFICATIONS MODULATE VARIATION IN THE EXPRESSION PATTERN OF TARGET GENES WITHOUT AFFECTING THE DNA SEQUENCE. THE CURRENT KNOWLEDGE OF EPIGENETIC RESEARCH FOCUSED ON THEIR ROLE IN THE PATHOGENESIS OF VARIOUS INFLAMMATORY DISEASES THAT CAUSES MORBIDITY AND MORTALITY WORLDWIDE. INFLAMMATORY DISEASES ARE CATEGORIZED AS ACUTE AND CHRONIC BASED ON THE DISEASE SEVERITY AND ARE REGULATED BY THE EXPRESSION PATTERN OF VARIOUS GENES. HENCE, UNDERSTANDING THE ROLE OF EPIGENETIC MODIFICATIONS DURING INFLAMMATION PROGRESSION WILL CONTRIBUTE TO THE DISEASE OUTCOMES AND THERAPEUTIC APPROACHES. THIS REVIEW ALSO FOCUSES ON THE METABOLOMICS APPROACH ASSOCIATED WITH THE STUDY OF INFLAMMATORY DISORDERS. INFLAMMATORY RESPONSES AND METABOLIC REGULATION ARE HIGHLY INTEGRATED AND VARIOUS ADVANCED TECHNIQUES ARE ADOPTED TO STUDY THE METABOLIC SIGNATURE MOLECULES. HERE WE DISCUSS SEVERAL METABOLOMICS APPROACHES USED TO LINK INFLAMMATORY DISORDERS AND EPIGENETIC CHANGES. WE PROPOSED THAT DECIPHERING THE MECHANISM BEHIND THE INFLAMMATION-METABOLISM LOOP MAY HAVE IMMENSE IMPORTANCE IN BIOMARKERS RESEARCH AND MAY ACT AS A PRINCIPAL COMPONENT IN DRUG DISCOVERY AS WELL AS THERAPEUTIC APPLICATIONS. 2022 18 4793 31 NUTRITIONAL FACTORS, DNA METHYLATION, AND RISK OF TYPE 2 DIABETES AND OBESITY: PERSPECTIVES AND CHALLENGES. A HEALTHY DIET IMPROVES LIFE EXPECTANCY AND HELPS TO PREVENT COMMON CHRONIC DISEASES SUCH AS TYPE 2 DIABETES (T2D) AND OBESITY. THE MECHANISMS DRIVING THESE EFFECTS ARE NOT FULLY UNDERSTOOD, BUT ARE LIKELY TO INVOLVE EPIGENETICS. EPIGENETIC MECHANISMS CONTROL GENE EXPRESSION, MAINTAINING THE DNA SEQUENCE, AND THEREFORE THE FULL GENOMIC INFORMATION INHERITED FROM OUR PARENTS, UNCHANGED. AN INTERESTING FEATURE OF EPIGENETIC CHANGES LIES IN THEIR DYNAMIC NATURE AND REVERSIBILITY. ACCORDINGLY, THEY ARE SUSCEPTIBLE TO CORRECTION THROUGH TARGETED INTERVENTIONS. HERE WE WILL REVIEW THE EVIDENCE SUPPORTING A ROLE FOR NUTRITIONAL FACTORS IN MEDIATING METABOLIC DISEASE RISK THROUGH DNA METHYLATION CHANGES. SPECIAL EMPHASIS WILL BE PLACED ON THE POTENTIAL OF USING DNA METHYLATION TRAITS AS BIOMARKERS TO PREDICT RISK OF OBESITY AND T2D AS WELL AS ON THEIR RESPONSE TO DIETARY AND PHARMACOLOGICAL (EPI-DRUG) INTERVENTIONS. 2019 19 3404 38 HOW EPIGENETICS IMPACTS ON HUMAN DISEASES. EPIGENETICS IS A RAPIDLY GROWING FIELD OF BIOLOGY THAT STUDIES THE CHANGES IN GENE EXPRESSION THAT ARE NOT DUE TO ALTERATIONS IN THE DNA SEQUENCE BUT RATHER THE CHEMICAL MODIFICATIONS OF DNA AND ITS ASSOCIATED PROTEINS. EPIGENETIC MECHANISMS CAN PROFOUNDLY INFLUENCE GENE EXPRESSION, CELL DIFFERENTIATION, TISSUE DEVELOPMENT, AND DISEASE SUSCEPTIBILITY. UNDERSTANDING EPIGENETIC CHANGES IS ESSENTIAL TO ELUCIDATE THE MECHANISMS UNDERLYING THE INCREASINGLY RECOGNIZED ROLE OF ENVIRONMENTAL AND LIFESTYLE FACTORS IN HEALTH AND DISEASE AND THE INTERGENERATIONAL TRANSMISSION OF PHENOTYPES. RECENT STUDIES SUGGEST EPIGENETICS MAY BE CRITICAL IN VARIOUS DISEASES, FROM CARDIOVASCULAR DISEASE AND CANCER TO NEURODEVELOPMENTAL AND NEURODEGENERATIVE DISORDERS. EPIGENETIC MODIFICATIONS ARE POTENTIALLY REVERSIBLE AND COULD PROVIDE NEW THERAPEUTIC AVENUES FOR TREATING THESE DISEASES USING EPIGENETIC MODULATORS. MOREOVER, EPIGENETICS PROVIDE INSIGHT INTO DISEASE PATHOGENESIS AND BIOMARKERS FOR DISEASE DIAGNOSIS AND RISK STRATIFICATION. NEVERTHELESS, EPIGENETIC INTERVENTIONS HAVE THE POTENTIAL FOR UNINTENDED CONSEQUENCES AND MAY POTENTIALLY LEAD TO INCREASED RISKS OF UNEXPECTED OUTCOMES, SUCH AS ADVERSE DRUG REACTIONS, DEVELOPMENTAL ABNORMALITIES, AND CANCER. THEREFORE, RIGOROUS STUDIES ARE ESSENTIAL TO MINIMIZE THE RISKS ASSOCIATED WITH EPIGENETIC THERAPIES AND TO DEVELOP SAFE AND EFFECTIVE INTERVENTIONS FOR IMPROVING HUMAN HEALTH. THIS ARTICLE PROVIDES A SYNTHETIC AND HISTORICAL VIEW OF THE ORIGIN OF EPIGENETICS AND SOME OF THE MOST RELEVANT ACHIEVEMENTS. 2023 20 2789 37 FACTORS INFLUENCING EPIGENETIC MECHANISMS: IS THERE A ROLE FOR BARIATRIC SURGERY? EPIGENETICS IS THE INTERACTION BETWEEN THE GENOME AND ENVIRONMENTAL STIMULI CAPABLE OF INFLUENCING GENE EXPRESSION DURING DEVELOPMENT AND AGING. A LARGE NUMBER OF STUDIES HAVE SHOWN THAT METABOLIC DISEASES ARE HIGHLY ASSOCIATED WITH EPIGENETIC ALTERATIONS, SUGGESTING THAT EPIGENETIC FACTORS MAY PLAY A CENTRAL ROLE IN OBESITY. TO INVESTIGATE THESE RELATIONSHIPS, WE FOCUS OUR ATTENTION ON THE MOST COMMON EPIGENETIC MODIFICATIONS THAT OCCUR IN OBESITY, INCLUDING DNA METHYLATION AND POST-TRANSLATIONAL MODIFICATIONS OF HISTONES. WE ALSO CONSIDER BARIATRIC SURGERY AS AN EPIGENETIC FACTOR, EVALUATING HOW THE ANATOMIC AND PHYSIOLOGIC MODIFICATIONS INDUCED BY THESE SURGICAL TECHNIQUES CAN CHANGE GENE EXPRESSION. HERE WE DISCUSS THE IMPORTANCE OF EPIGENETIC MECHANISMS IN CHRONIC DISEASE AND CANCER, AND THE ROLE OF EPIGENETIC DISTURBANCES IN OBESITY, WITH A FOCUS ON THE ROLE OF BARIATRIC SURGERY. 2020