1 3435 136 HYPERGLYCEMIA AND VASCULAR METABOLIC MEMORY: TRUTH OR FICTION? PREVENTION OF LONG-TERM COMPLICATIONS REMAINS THE MAIN CHALLENGE IN THE TREATMENT OF DIABETES. A STRONG RELATIONSHIP BETWEEN GLUCOSE CONTROL AND DEVELOPMENT OF COMPLICATIONS IS APPARENT IN ALL EPIDEMIOLOGIC STUDIES. YET, INTERVENTION TRIALS HAVE YIELDED QUESTIONABLE RESULTS, PARTICULARLY WHEN INTENSIVE TREATMENT WAS INTRODUCED IN PATIENTS WITH LONG-STANDING DIABETES. IT HAS BEEN POSTULATED THAT IN THESE SUBJECTS, PRIOR EXPOSURE TO CHRONIC HYPERGLYCEMIA MAY HAVE GENERATED A NEGATIVE "METABOLIC MEMORY," PREVENTING FULL EXERTION OF THE BENEFICIAL EFFECTS OF ANY SUBSEQUENT IMPROVEMENT OF GLUCOSE CONTROL. THIS PHENOMENON HAS BEEN REPLICATED IN ANIMAL MODELS AND IT RECOGNIZES A MOLECULAR BASIS IN THE ROLE OF OXIDATIVE STRESS, ADVANCED GLYCATION PROCESSES, AND EPIGENETIC MECHANISMS ACCOUNTING FOR SELF-PERPETUATING MODIFICATIONS OF GENE EXPRESSION. CONVERSELY, EARLY INTERVENTION IN BOTH TYPE 1 AND TYPE 2 DIABETES HAS PROVEN THAT GOOD GLYCEMIC CONTROL REDUCES THE RISK OF DEVELOPMENT AND PROGRESSION OF COMPLICATIONS WITH A BENEFICIAL EFFECT THAT EXTENDS WELL BEYOND THE DURATION OF NEAR-NORMOGLYCEMIA. THIS HAS BROUGHT UP THE CONCEPT OF "METABOLIC LEGACY," AN ADVANTAGE HANDED DOWN BY EARLY AND EFFECTIVE IMPLEMENTATION OF TREATMENTS DESIGNED TO REDUCE BLOOD GLUCOSE LEVELS AS SAFELY AS POSSIBLE ALONG WITH MULTIFACTORIAL INTERVENTION OF ALL CARDIOVASCULAR RISK FACTORS. THE EVIDENCE, NATURE, AND CLINICAL IMPLICATION OF THESE CONCEPTS ARE REVIEWED. 2013 2 5997 46 THE "METABOLIC MEMORY" THEORY AND THE EARLY TREATMENT OF HYPERGLYCEMIA IN PREVENTION OF DIABETIC COMPLICATIONS. SEVERAL EPIDEMIOLOGICAL AND PROSPECTIVE STUDIES SUGGEST THAT AN EARLY INTENSIVE CONTROL OF HYPERGLYCAEMIA IS ABLE TO DECREASE THE RISK OF DIABETIC MICRO- AND MACRO-VASCULAR COMPLICATIONS. A GROWING BODY OF EXPERIMENTAL EVIDENCE SUPPORTS THE CONCEPT THAT THE RISK FOR DIABETES COMPLICATIONS MAY BE LINKED TO OXIDATIVE STRESS, NON-ENZYMATIC GLYCATION OF PROTEINS, EPIGENETIC CHANGES, AND CHRONIC INFLAMMATION, LAYING THE FOUNDATION FOR THE "METABOLIC MEMORY" THEORY. FROM A CLINICAL POINT OF VIEW, THIS THEORY SUPPORTS THE NEED FOR A VERY EARLY AGGRESSIVE TREATMENT, WITH THE GOAL OF NORMALIZING METABOLIC CONTROL AS SOON AS POSSIBLE. IT MAY ALSO PROVE BENEFICIAL TO INTRODUCE THERAPEUTIC AGENTS THAT ARE ABLE TO REDUCE REACTIVE SPECIES AND GLYCATION, IN ADDITION TO PRESENTING BETTER CONTROL OF GLUCOSE LEVELS IN PATIENTS WITH DIABETES, IN ORDER TO MINIMIZE LONG-TERM DIABETES COMPLICATIONS. IN THIS REVIEW, WE EVALUATE THE EFFECT OF GLUCOSE INTAKE AND METABOLISM IN THE LIGHT OF THIS THEORY. 2017 3 4195 52 METABOLIC MEMORY: MECHANISMS AND IMPLICATIONS FOR DIABETIC RETINOPATHY. CHRONIC HYPERGLYCEMIA OF DIABETES LEADS TO MICROVASCULAR COMPLICATIONS THAT SEVERELY IMPACT QUALITY OF LIFE. DIABETIC RETINOPATHY (DR) MAY BE THE MOST COMMON OF THESE AND IS A LEADING CAUSE OF VISUAL IMPAIRMENT AND BLINDNESS AMONG WORKING AGE ADULTS IN DEVELOPED NATIONS. MANY LARGE-SCALE TYPE 1 AND TYPE 2 DIABETES CLINICAL TRIALS HAVE DEMONSTRATED THAT EARLY INTENSIVE GLYCEMIC CONTROL CAN REDUCE THE INCIDENCE AND PROGRESSION OF MICRO AND MACROVASCULAR COMPLICATIONS. ON THE OTHER HAND, EPIDEMIOLOGICAL AND PROSPECTIVE DATA HAVE REVEALED THAT THE STRESSORS OF DIABETIC VASCULATURE PERSIST BEYOND THE POINT WHEN GLYCEMIC CONTROL HAS BEEN ACHIEVED. THESE KINDS OF PERSISTENT ADVERSE EFFECTS OF HYPERGLYCEMIA ON THE DEVELOPMENT AND PROGRESSION OF COMPLICATIONS HAS BEEN DEFINED AS "METABOLIC MEMORY", AND OXIDATIVE STRESS, ADVANCED GLYCATION END PRODUCTS AND EPIGENETIC CHANGES HAVE BEEN IMPLICATED IN THE PROCESS. RECENT STUDIES HAVE INDICATED THAT SUCH "HYPERGLYCEMIC MEMORY" MAY ALSO INFLUENCE DR, SUGGESTING THAT MANIPULATION OF HYPERGLYCEMIC MEMORY MAY PROVE A BENEFICIAL APPROACH TO PREVENTION AND TREATMENT. THIS REVIEW SUMMARIZES THE EVIDENCE FROM DR-RELATED CLINICAL TRIALS AND MECHANISTIC STUDIES TO INVESTIGATE THE SIGNIFICANCE OF METABOLIC MEMORY IN DR AND UNDERSTAND ITS POTENTIAL AS A TARGET OF MOLECULAR THERAPEUTICS AIMED AT REVERSING HYPERGLYCEMIC MEMORY. 2012 4 2190 47 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 5 2028 42 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 6 4193 45 METABOLIC MEMORY AND DIABETIC NEPHROPATHY: BENEFICIAL EFFECTS OF NATURAL EPIGENETIC MODIFIERS. NEPHROPATHY IS ONE OF THE MOST FREQUENT COMPLICATIONS OF CHRONIC DIABETES. THE MAIN REASON FOR NEPHROPATHY DESPITE BEING HYPERGLYCEMIA, BUT IT PROGRESSES EVEN AFTER GOOD GLYCEMIC CONTROL HAS BEEN ACHIEVED IN DIABETIC PATIENTS. THE EFFECTS OF PRIOR EXPOSURE TO HIGH BLOOD GLUCOSE CONDITIONS DEPEND UPON THE SEVERITY AND DURATION OF THIS EXPOSURE, INDICATING A "METABOLIC MEMORY" PHENOMENON. HYPERGLYCEMIA NOT ONLY INCREASES OXIDATIVE STRESS BUT IS ALSO ALLEGED TO START SEVERAL BIOCHEMICAL ANOMALIES AND ALTER GENE EXPRESSION ASSOCIATED WITH METABOLIC HOMEOSTASIS. HIGH GLUCOSE LEVELS INDUCE EPIGENETIC MODIFICATIONS THAT ALTER GENE EXPRESSION WITHOUT CHANGING DNA SEQUENCES. THESE EPIGENETIC MODIFICATIONS HAVE SHOWN TO BE REVERSIBLE AND HAVE THE POTENTIAL TO CEASE ADVERSE EFFECTS IF GOOD GLYCEMIC CONTROL IS ACHIEVED FROM INITIATION OF DIABETES. HOWEVER, IF GOOD GLYCEMIC CONTROL IS NOT ACHIEVED FOR MONTHS, THESE MODIFICATIONS STAND FIRM TO REVERSALS. THERAPIES AND DRUGS HAVE BEEN IN USE TO PREVENT EPIGENETIC MODIFICATIONS AND OXIDATIVE STRESS, WHICH ALSO HELPED IN AMELIORATING DIABETIC NEPHROPATHY. BUT THESE SYNTHETIC DRUGS ARE LOADED WITH SIDE EFFECTS LIKE INCREASED BODY WEIGHT, KIDNEY DYSFUNCTION ETC. SO PHYTOCHEMICALS ARE EMERGING AS ALTERNATIVES AND MANY OF THEM HAVE ALREADY BEEN USED TO TREAT NEPHROPATHY. BUT STILL, THERE IS RIGOROUS NEED TO EVALUATE PHYTOCHEMICALS WHICH CAN REGULATE EPIGENETIC EVENTS AND HAVE THE POTENTIAL TO DECELERATE THE FURTHER PROGRESSION OF THESE LIFE-THREATENING DISEASES. IN THIS REVIEW ARTICLE WE DISCUSS THE POTENTIAL EPIGENETIC MODIFIERS FROM PLANTS THAT CAN ERASE METABOLIC MEMORY AND CAN THUS BE PROTECTIVE AGAINST DIABETIC NEPHROPATHY. 2020 7 2163 40 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 8 2062 31 EPIGENETIC CONTROL OF HYPERTENSION BY DNA METHYLATION: A REAL POSSIBILITY. HYPERTENSION IS A COMMON CHRONIC DISEASE THAT PARTICULARLY AFFECTS THE ELDERLY AND CAN TRIGGER SEVERAL CARDIOVASCULAR CONDITIONS. ALTHOUGH THE TREATMENT OF HYPERTENSION HAS EVOLVED IN RECENT DECADES, MANY HYPERTENSIVE PATIENTS STILL DO NOT HAVE PROPERLY CONTROLLED BLOOD PRESSURE. ACCUMULATING EVIDENCE SUPPORTS THE HYPOTHESIS THAT DNA METHYLATION PLAYS AN IMPORTANT ROLE IN REGULATING GENE EXPRESSION, ALTERING THE PHENOTYPE AND FUNCTION OF THE CARDIOVASCULAR SYSTEM. THE PRESENT REVIEW HIGHLIGHTS RECENT ADVANCES IN RESEARCH ON DNA METHYLATION IN THE DEVELOPMENT OF HYPERTENSION. SEVERAL PRECLINICAL AND CLINICAL EVIDENCE SHOW THAT METHYLATION OF DIFFERENT TARGETS APPEARS TO BE INVOLVED IN HYPERTENSION. STUDIES OF THE INVOLVEMENT OF DNA METHYLATION HAVE GREATLY IMPROVED OUR UNDERSTANDING OF HYPERTENSION, BUT ITS USE AS A VALID THERAPEUTIC TARGET IS STILL UNKNOWN. FURTHER STUDIES COULD HELP TO BRING TO LIGHT THE TRUTH ABOUT GENE THERAPY IN HYPERTENSION. 2021 9 3848 30 IS EPIGENETICS AN IMPORTANT LINK BETWEEN EARLY LIFE EVENTS AND ADULT DISEASE? BACKGROUND: EPIGENETIC MECHANISMS PROVIDE ONE POTENTIAL EXPLANATION FOR HOW ENVIRONMENTAL INFLUENCES IN EARLY LIFE CAUSE LONG-TERM CHANGES IN CHRONIC DISEASE SUSCEPTIBILITY. WHEREAS EPIGENETIC DYSREGULATION IS INCREASINGLY IMPLICATED IN VARIOUS RARE DEVELOPMENTAL SYNDROMES AND CANCER, THE ROLE OF EPIGENETICS IN COMPLEX CHRONIC DISEASES, SUCH AS CARDIOVASCULAR DISEASE, TYPE 2 DIABETES AND OBESITY, REMAINS LARGELY UNCHARACTERIZED. EXTENSIVE WORK IN ANIMAL MODELS IS REQUIRED TO DEVELOP SPECIFIC HYPOTHESES THAT CAN BE PRACTICABLY TESTED IN HUMANS. ANIMAL MODELS: WE HAVE DEVELOPED A MOUSE MODEL SHOWING THAT METHYL DONOR SUPPLEMENTATION PREVENTS TRANSGENERATIONAL AMPLIFICATION OF OBESITY, SUGGESTING A ROLE FOR DNA METHYLATION IN THE DEVELOPMENTAL ESTABLISHMENT OF BODY WEIGHT REGULATION. CONCLUSIONS: COUPLING SUCH MODELS WITH RECENTLY DEVELOPED EPIGENOMIC TECHNOLOGIES SHOULD ULTIMATELY ENABLE US TO DETERMINE IF EPIGENETICS IS AN IMPORTANT LINK BETWEEN EARLY LIFE EVENTS AND ADULT DISEASE. 2009 10 4125 36 MECHANISMS OF DISEASE: IN UTERO PROGRAMMING IN THE PATHOGENESIS OF HYPERTENSION. NUTRITIONAL AND OTHER ENVIRONMENTAL CUES DURING DEVELOPMENT CAN PERMANENTLY ALTER THE STRUCTURE, HOMEOSTATIC SYSTEMS, AND FUNCTIONS OF THE BODY. THIS PHENOMENON HAS BEEN REFERRED TO AS 'PROGRAMMING'. EPIDEMIOLOGICAL AND ANIMAL STUDIES SHOW THAT PROGRAMMED EFFECTS OPERATE WITHIN THE NORMAL RANGE OF GROWTH AND DEVELOPMENT, AND INFLUENCE THE RISK OF CHRONIC DISEASE IN ADULT LIFE. WE REVIEW THE EVIDENCE THAT THESE EFFECTS INCLUDE REDUCED NEPHRON NUMBER AND COMPENSATORY ADAPTATIONS, WHICH MIGHT LEAD TO HYPERTENSION, AND PERHAPS ACCELERATE THE DECLINE IN RENAL FUNCTION THAT ACCOMPANIES AGING. THESE PROCESSES MIGHT BE EXACERBATED BY PROGRAMMED CHANGES IN VASCULAR STRUCTURE AND FUNCTION, AND ALTERATIONS IN ENDOCRINE AND METABOLIC HOMEOSTASIS. PROGRAMMED EFFECTS MIGHT BE INITIATED AS EARLY AS THE PERICONCEPTUAL PHASE OF DEVELOPMENT, AND COULD INVOLVE EPIGENETIC CHANGES IN GENE EXPRESSION OR ALTERED STEM CELL ALLOCATION. BETTER UNDERSTANDING OF THESE PROCESSES COULD LEAD TO THE DEVELOPMENT OF NOVEL DIAGNOSTIC AND PREVENTIVE MEASURES, AND TO EARLY DETECTION OF AT-RISK INDIVIDUALS. BY MONITORING BLOOD PRESSURE, WEIGHT, AND RENAL FUNCTION IN CHILDREN, IT MIGHT BE POSSIBLE TO REDUCE THE RISK OF CARDIOVASCULAR AND RENAL DISEASE IN LATER LIFE. 2006 11 1371 43 DEVELOPMENTAL ORIGINS OF HEALTH AND DISEASE: NEW INSIGHTS. EPIDEMIOLOGICAL AND ANIMAL STUDIES SHOW THAT SMALL CHANGES IN THE DEVELOPMENTAL ENVIRONMENT CAN INDUCE PHENOTYPIC CHANGES AFFECTING AN INDIVIDUAL'S RESPONSES TO THEIR LATER ENVIRONMENT. THESE MAY ALTER THE RISK OF CHRONIC DISEASE SUCH AS METABOLIC SYNDROME OR CARDIOVASCULAR DISEASE. RECENT RESEARCH SHOWS THAT ANIMALS EXPOSED TO SUCH A MISMATCH BETWEEN PRENATAL AND POSTNATAL ENVIRONMENT DEVELOP OBESITY, REDUCED ACTIVITY, LEPTIN AND INSULIN RESISTANCE, ELEVATED BLOOD PRESSURE AND VASCULAR ENDOTHELIAL DYSFUNCTION. EPIGENETIC PROCESSES ARE INVOLVED IN SUCH EFFECTS, TARGETED TO PROMOTER REGIONS OF SPECIFIC GENES IN SPECIFIC TISSUES. SUCH FINE CONTROL OF GENE EXPRESSION SUGGESTS THAT THE MECHANISMS HAVE BEEN RETAINED THROUGH EVOLUTION THROUGH THEIR ADAPTIVE ADVANTAGE, RATHER THAN REPRESENTING EXTREME EFFECTS OF DEVELOPMENTAL DISRUPTION AKIN TO TERATOGENESIS. THERE MAY BE ADAPTIVE ADVANTAGE IN A DEVELOPMENTAL CUE INDUCING A PHENOTYPIC CHANGE IN GENERATIONS BEYOND THE IMMEDIATE PREGNANCY, AND A RANGE OF DATA THAT SUPPORT THIS CONCEPT. IN ANIMALS, EPIGENETIC EFFECTS SUCH AS DNA METHYLATION CAN BE PASSED TO SUCCESSIVE GENERATIONS. ENVIRONMENTAL TOXINS, INCLUDING ENDOCRINE DISRUPTORS, MAY INDUCE GREATER RISK OF CHRONIC DISEASE, EVEN AT LOW EXPOSURE LEVELS, IF THEY AFFECT SUCH NORMAL DEVELOPMENTAL EPIGENETIC PROCESSES. APPROPRIATE INTERVENTIONS MAY HAVE LONG-TERM MULTIGENERATIONAL EFFECTS TO REDUCE THE RISK OF CHRONIC DISEASE. 2008 12 4192 36 METABOLIC MEMORY AND CHRONIC DIABETES COMPLICATIONS: POTENTIAL ROLE FOR EPIGENETIC MECHANISMS. RECENT ESTIMATES INDICATE THAT DIABETES MELLITUS CURRENTLY AFFECTS MORE THAN 10 % OF THE WORLD'S POPULATION. EVIDENCE FROM BOTH THE LABORATORY AND LARGE SCALE CLINICAL TRIALS HAS REVEALED THAT PROLONGED HYPERGLYCEMIA INDUCES CHRONIC COMPLICATIONS WHICH PERSIST AND PROGRESS UNIMPEDED EVEN WHEN GLYCEMIC CONTROL IS PHARMACEUTICALLY ACHIEVED VIA THE PHENOMENON OF METABOLIC MEMORY. THE EPIGENOME IS COMPRISED OF ALL CHROMATIN MODIFICATIONS INCLUDING POST TRANSLATIONAL HISTONE MODIFICATION, EXPRESSION CONTROL VIA MIRNAS AND THE METHYLATION OF CYTOSINE WITHIN DNA. MODIFICATIONS OF THESE EPIGENETIC MARKS NOT ONLY ALLOW CELLS AND ORGANISMS TO QUICKLY RESPOND TO CHANGING ENVIRONMENTAL STIMULI BUT ALSO CONFER THE ABILITY OF THE CELL TO "MEMORIZE" THESE ENCOUNTERS. AS SUCH, THESE PROCESSES HAVE GAINED MUCH ATTENTION AS POTENTIAL MOLECULAR MECHANISMS UNDERLYING METABOLIC MEMORY AND CHRONIC DIABETIC COMPLICATIONS. HERE WE PRESENT A REVIEW OF THE VERY RECENT LITERATURE PUBLISHED PERTAINING TO THIS SUBJECT. 2012 13 6812 35 [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 14 2613 50 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 15 5821 37 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 16 6905 26 [THE ROLE OF EPIGENETIC REGULATIONS IN EARLY CHILDHOOD DISEASES]. WITH THE ACCEPTANCE OF "THE DEVELOPMENTAL ORIGINS OF HEALTH AND DISEASE" CONCEPT IN THE 1990S, IT BECAME CLEAR THAT EPIGENETIC INHERITANCE, WHICH DO NOT INVOLVE CHANGES IN THE DNA SEQUENCE HAS IMPORTANT ROLE IN THE PATHOGENESIS OF DISEASES. EPIGENETIC REGULATION SERVES THE ADAPTATION TO THE CHANGING ENVIRONMENT AND MAINTAINS THE REPRODUCTIVE FITNESS EVEN ON THE DRAWBACK OF INCREASED RISK OF DISEASES IN LATER LIFE. THE ROLE OF EPIGENETIC MECHANISMS IN CHRONIC NON-COMMUNICABLE DISEASES HAS BEEN WELL ESTABLISHED. RECENT STUDIES HAVE REVEALED THAT EPIGENETIC CHANGES HAVE ALSO CAUSAL ROLE IN CERTAIN PEDIATRIC DISEASES. THE REVIEW EVALUATES THE RECENT EPIGENETIC FINDINGS IN THE PATHOMECHANISM OF COMMON PEDIATRIC DISEASES. THE WIDE RANGE AND LONG-LASTING DURATION OF EPIGENETIC REGULATIONS GIVE IMPORTANCE TO THE SUBJECT. METHODS ARE ALREADY AVAILABLE TO EVALUATE A PART OF THE EPIGENETIC CHANGES IN THE CLINICAL PRACTICE, PRESENTLY AIMING PRIMARILY THE ESTIMATION OF THE DISEASE RISK OR DEFINITION OF DIAGNOSIS. FURTHERMORE, THERE ARE ALREADY AVAILABLE LIMITED MEANS TO INFLUENCE THE EPIGENETIC REGULATION. 2019 17 6204 37 THE INFLUENCE OF EPIGENETICS AND INFLAMMATION ON CARDIOMETABOLIC RISKS. CARDIOMETABOLIC DISEASES INCLUDE METABOLIC SYNDROME, OBESITY, TYPE 2 DIABETES MELLITUS, AND HYPERTENSION. EPIGENETIC MODIFICATIONS PARTICIPATE IN CARDIOMETABOLIC DISEASES THROUGH SEVERAL PATHWAYS, INCLUDING INFLAMMATION, VASCULAR DYSFUNCTION, AND INSULIN RESISTANCE. EPIGENETIC MODIFICATIONS, WHICH ENCOMPASS ALTERATIONS TO GENE EXPRESSION WITHOUT MUTATING THE DNA SEQUENCE, HAVE GAINED MUCH ATTENTION IN RECENT YEARS, SINCE THEY HAVE BEEN CORRELATED WITH CARDIOMETABOLIC DISEASES AND MAY BE TARGETED FOR THERAPEUTIC INTERVENTIONS. EPIGENETIC MODIFICATIONS ARE GREATLY INFLUENCED BY ENVIRONMENTAL FACTORS, SUCH AS DIET, PHYSICAL ACTIVITY, CIGARETTE SMOKING, AND POLLUTION. SOME MODIFICATIONS ARE HERITABLE, INDICATING THAT THE BIOLOGICAL EXPRESSION OF EPIGENETIC ALTERATIONS MAY BE OBSERVED ACROSS GENERATIONS. MOREOVER, MANY PATIENTS WITH CARDIOMETABOLIC DISEASES PRESENT WITH CHRONIC INFLAMMATION, WHICH CAN BE INFLUENCED BY ENVIRONMENTAL AND GENETIC FACTORS. THE INFLAMMATORY ENVIRONMENT WORSENS THE PROGNOSIS OF CARDIOMETABOLIC DISEASES AND FURTHER INDUCES EPIGENETIC MODIFICATIONS, PREDISPOSING PATIENTS TO THE DEVELOPMENT OF OTHER METABOLISM-ASSOCIATED DISEASES AND COMPLICATIONS. A DEEPER UNDERSTANDING OF INFLAMMATORY PROCESSES AND EPIGENETIC MODIFICATIONS IN CARDIOMETABOLIC DISEASES IS NECESSARY TO IMPROVE OUR DIAGNOSTIC CAPABILITIES, PERSONALIZED MEDICINE APPROACHES, AND THE DEVELOPMENT OF TARGETED THERAPEUTIC INTERVENTIONS. FURTHER UNDERSTANDING MAY ALSO ASSIST IN PREDICTING DISEASE OUTCOMES, ESPECIALLY IN CHILDREN AND YOUNG ADULTS. THIS REVIEW DESCRIBES EPIGENETIC MODIFICATIONS AND INFLAMMATORY PROCESSES UNDERLYING CARDIOMETABOLIC DISEASES, AND FURTHER DISCUSSES ADVANCES IN THE RESEARCH FIELD WITH A FOCUS ON SPECIFIC POINTS FOR INTERVENTIONAL THERAPY. 2023 18 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 19 3748 51 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 20 4425 37 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