1 6341 80 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 2 2613 44 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 3 4195 37 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 3156 30 GLYCEMIC MEMORIES AND THE EPIGENETIC COMPONENT OF DIABETIC NEPHROPATHY. A STRONG CASE FOR THE DEREGULATION OF EPIGENETIC CHROMATIN MODIFICATIONS IN THE DEVELOPMENT AND PROGRESSION OF VARIOUS CHRONIC COMPLICATIONS OF DIABETES HAS EMERGED FROM RECENT EXPERIMENTAL OBSERVATIONS. CLINICAL TRIALS OF TYPE 1 AND TYPE 2 DIABETES PATIENTS HIGHLIGHT THE IMPORTANCE OF EARLY AND INTENSIVE TREATMENT AND THE PROLONGED DAMAGE OF HYPERGLYCEMIA ON ORGANS SUCH AS THE KIDNEY. THE FUNCTIONAL RELATIONSHIP BETWEEN THE REGULATION OF CHROMATIN ARCHITECTURE AND PERSISTENT GENE EXPRESSION CHANGES CONFERRED BY PRIOR HYPERGLYCEMIA REPRESENTS AN IMPORTANT AVENUE OF INVESTIGATION FOR EXPLAINING DIABETIC NEPHROPATHY. WHILE SEVERAL STUDIES IMPLICATE EPIGENETIC CHANGES AT THE CHROMATIN TEMPLATE IN THE DEREGULATED GENE EXPRESSION ASSOCIATED WITH DIABETIC NEPHROPATHY, THE MOLECULAR DETERMINANTS OF METABOLIC MEMORY IN RENAL CELLS REMAIN POORLY UNDERSTOOD. THERE IS NOW STRONG EVIDENCE FROM EXPERIMENTAL ANIMALS AND CELL CULTURE OF PERSISTENT GLUCOSE-DRIVEN CHANGES IN VASCULAR ENDOTHELIAL GENE EXPRESSION THAT MAY ALSO HAVE RELEVANCE FOR THE MICROVASCULATURE OF THE KIDNEY. EXPLORATION OF EPIGENETIC MECHANISMS UNDERLYING THE HYPERGLYCEMIC CUE MEDIATING PERSISTENT TRANSCRIPTIONAL CHANGES IN RENAL CELLS HOLDS NOVEL THERAPEUTIC POTENTIAL FOR DIABETIC NEPHROPATHY. 2013 5 2491 38 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 6 2163 29 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 7 2965 41 GENETIC AND EPIGENETIC MODIFICATIONS IN THE PATHOGENESIS OF DIABETIC RETINOPATHY: A MOLECULAR LINK TO REGULATE GENE EXPRESSION. INTENSIFICATION IN THE FREQUENCY OF DIABETES AND THE ASSOCIATED VASCULAR COMPLICATIONS HAS BEEN A ROOT CAUSE OF BLINDNESS AND VISUAL IMPAIRMENT WORLDWIDE. ONE SUCH VASCULAR COMPLICATION WHICH HAS BEEN THE PROMINENT CAUSE OF BLINDNESS; RETINAL VASCULATURE, NEURONAL AND GLIAL ABNORMALITIES IS DIABETIC RETINOPATHY (DR), A CHRONIC COMPLICATED OUTCOME OF TYPE 1 AND TYPE 2 DIABETES. IT HAS ALSO BECOME CLEAR THAT "GENETIC" VARIATIONS IN POPULATION ALONE CAN'T EXPLAIN THE DEVELOPMENT AND PROGRESSION OF DIABETES AND ITS COMPLICATIONS INCLUDING DR. DR EXPERIENCES ENGAGEMENT OF FOREMOST MEDIATORS OF DIABETES SUCH AS HYPERGLYCEMIA, OXIDANT STRESS, AND INFLAMMATORY FACTORS THAT LEAD TO THE DYSREGULATION OF "EPIGENETIC" MECHANISMS INVOLVING HISTONE ACETYLATION AND HISTONE AND DNA METHYLATION, CHROMATIN REMODELING AND EXPRESSION OF A COMPLEX SET OF STRESS-REGULATED AND DISEASE-ASSOCIATED GENES. IN ADDITION, BOTH ELEVATED GLUCOSE CONCENTRATION AND INSULIN RESISTANCE LEAVE A ROBUST EFFECT ON EPIGENETIC REPROGRAMMING OF THE ENDOTHELIAL CELLS TOO, SINCE ENDOTHELIUM ASSOCIATED WITH THE EYE AIDS IN MAINTAINING THE VASCULAR HOMEOSTASIS. FURTHERMORE, SEVERAL STUDIES CONDUCTED ON THE DISEASE SUGGEST THAT THE MODIFICATIONS OF THE EPIGENOME MIGHT BE THE FUNDAMENTAL MECHANISM(S) FOR THE PROPOSED METABOLIC MEMORY' RESULTING INTO PROLONGED GENE EXPRESSION FOR INFLAMMATION AND CELLULAR DYSFUNCTION EVEN AFTER ATTAINING THE GLYCEMIC CONTROL IN DIABETICS. HENCEFORTH, THE PRESENT REVIEW FOCUSES ON THE ASPECTS OF GENETIC AND EPIGENETIC ALTERATIONS IN GENES SUCH AS VASCULAR ENDOTHELIAL GROWTH FACTOR AND ALDOSE REDUCTASE CONSIDERED BEING ASSOCIATED WITH DR. IN ADDITION, WE DISCUSS BRIEFLY THE ROLE OF THE THIOREDOXIN-INTERACTING PROTEIN TXNIP, WHICH IS STRONGLY INDUCED BY HIGH GLUCOSE AND DIABETES, IN CELLULAR OXIDATIVE STRESS AND MITOCHONDRIAL DYSFUNCTION POTENTIALLY LEADING TO CHROMATIN REMODELING AND OCULAR COMPLICATIONS OF DIABETES. THE IDENTIFICATION OF DISEASE-ASSOCIATED GENES AND THEIR EPIGENETIC REGULATIONS WILL LEAD TO POTENTIAL NEW DRUGS AND GENE THERAPIES AS WELL AS PERSONALIZED MEDICINE TO PREVENT OR SLOW DOWN THE PROGRESSION OF DR. 2016 8 2549 35 EPIGENETICS IN OBESITY AND DIABETES MELLITUS: NEW INSIGHTS. A LONG-TERM COMPLICATION OF OBESITY IS THE DEVELOPMENT OF TYPE 2 DIABETES (T2D). PATIENTS WITH T2D HAVE BEEN DESCRIBED AS HAVING EPIGENETIC MODIFICATIONS. EPIGENETICS IS THE POST-TRANSCRIPTIONAL MODIFICATION OF DNA OR ASSOCIATED FACTORS CONTAINING GENETIC INFORMATION. THESE ENVIRONMENTALLY-INFLUENCED MODIFICATIONS, MAINTAINED DURING CELL DIVISION, CAUSE STABLE CHANGES IN GENE EXPRESSION. EPIGENETIC MODIFICATIONS OF T2D ARE DNA METHYLATION, ACETYLATION, UBIQUITYLATION, SUMOYLATION, AND PHOSPHORYLATION AT THE LYSINE RESIDUE AT THE AMINO TERMINUS OF HISTONES, AFFECTING DNA, HISTONES, AND NON-CODING RNA. DNA METHYLATION HAS BEEN SHOWN IN PANCREATIC ISLETS, ADIPOSE TISSUE, SKELETAL MUSCLE, AND THE LIVER. FURTHERMORE, EPIGENETIC CHANGES HAVE BEEN OBSERVED IN CHRONIC COMPLICATIONS OF T2D, SUCH AS DIABETIC NEPHROPATHY, DIABETIC RETINOPATHY, AND DIABETIC NEUROPATHY. RECENTLY, A NEW DRUG HAS BEEN DEVELOPED WHICH ACTS ON BROMODOMAINS AND EXTRATERMINAL (BET) DOMAIN PROTEINS, WHICH OPERATE LIKE EPIGENETIC READERS AND COMMUNICATE WITH CHROMATIN TO MAKE DNA ACCESSIBLE FOR TRANSCRIPTION BY INHIBITING THEM. THIS DRUG (APABETALONE) IS BEING STUDIED TO PREVENT MAJOR ADVERSE CARDIOVASCULAR EVENTS IN PEOPLE WITH T2D, LOW HDL CHOLESTEROL, CHRONIC KIDNEY FAILURE, AND RECENT CORONARY EVENTS. THIS REVIEW AIMS TO DESCRIBE THE RELATIONSHIP BETWEEN OBESITY, LONG-TERM COMPLICATIONS SUCH AS T2D, AND EPIGENETIC MODIFICATIONS AND THEIR POSSIBLE TREATMENTS. 2023 9 776 31 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 10 3748 36 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 11 2190 39 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 12 4192 34 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 2028 28 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 6067 33 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 15 2009 30 EPIGENETIC BASIS OF DIABETIC VASCULOPATHY. TYPE 2 DIABETES MELLITUS (T2DM) CAUSES PERIPHERAL VASCULAR DISEASE BECAUSE OF WHICH SEVERAL BLOOD-BORNE FACTORS, INCLUDING VITAL NUTRIENTS FAIL TO REACH THE AFFECTED TISSUE. TISSUE EPIGENOME IS SENSITIVE TO CHRONIC HYPERGLYCEMIA AND IS KNOWN TO CAUSE PATHOGENESIS OF MICRO- AND MACROVASCULAR COMPLICATIONS. THESE VASCULAR COMPLICATIONS OF T2DM MAY PERPETUATE THE ONSET OF ORGAN DYSFUNCTION. THE BURDEN OF DIABETES IS PRIMARILY BECAUSE OF A WIDE RANGE OF COMPLICATIONS OF WHICH NONHEALING DIABETIC ULCERS REPRESENT A MAJOR COMPONENT. THUS, IT IS IMPERATIVE THAT CURRENT RESEARCH HELP RECOGNIZE MORE EFFECTIVE METHODS FOR THE DIAGNOSIS AND MANAGEMENT OF EARLY VASCULAR INJURIES. THIS REVIEW ADDRESSES THE SIGNIFICANCE OF EPIGENETIC PROCESSES SUCH AS DNA METHYLATION AND HISTONE MODIFICATIONS IN THE EVOLUTION OF MACROVASCULAR AND MICROVASCULAR COMPLICATIONS OF T2DM. 2022 16 2171 34 EPIGENETIC MECHANISMS IN THE PATHOGENESIS OF DIABETIC FOOT ULCERS. THE INCIDENCE OF DIABETES MELLITUS, A CHRONIC METABOLIC DISEASE ASSOCIATED WITH BOTH PREDISPOSING GENETIC AND ENVIRONMENTAL FACTORS, IS INCREASING GLOBALLY. AS A RESULT, IT IS EXPECTED THAT THERE WILL ALSO BE AN INCREASING INCIDENCE OF DIABETIC COMPLICATIONS WHICH ARISE AS A RESULT OF POOR GLYCEMIC CONTROL. COMPLICATIONS INCLUDE CARDIOVASCULAR DISEASES, NEPHROPATHY, RETINOPATHY AND DIABETIC FOOT ULCERS. THE FINDINGS OF SEVERAL MAJOR CLINICAL TRIALS HAVE IDENTIFIED THAT DIABETIC COMPLICATIONS MAY ARISE EVEN AFTER MANY YEARS OF PROPER GLYCEMIC CONTROL. THIS HAS LED TO THE CONCEPT OF PERSISTENT EPIGENETIC CHANGES. VARIOUS EPIGENETIC MECHANISMS HAVE BEEN IDENTIFIED AS IMPORTANT CONTRIBUTORS TO THE PATHOGENESIS OF DIABETES AND DIABETIC COMPLICATIONS. THE AIM OF THIS REVIEW IS TO PROVIDE AN OVERVIEW OF THE PATHOBIOLOGY OF TYPE 2 DIABETES WITH AN EMPHASIS ON COMPLICATIONS, PARTICULARLY DIABETIC FOOT ULCERS. AN OVERVIEW OF EPIGENETIC MECHANISMS IS PROVIDED AND THE FOCUS IS ON THE EMERGING EVIDENCE FOR ABERRANT EPIGENETIC MECHANISMS IN DIABETIC FOOT ULCERS. 2012 17 5997 29 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 18 4193 34 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 19 6902 39 [THE IMPACT OF CHROMATIN MODIFICATION ON THE DEVELOPMENT OF CHRONIC COMPLICATIONS IN PATIENTS WITH DIABETES]. DIABETES IS A CHRONIC, METABOLIC DISEASE. OVER 347 MILLION PEOPLE WORLDWIDE HAVE DIABETES. CHRONIC COMPLICATIONS (RETINOPATHY, NEPHROPATHY OR NEUROPATHY) ARE THE MAJOR DANGEROUS OUTCOME OF THIS DISEASE. RECENT STUDIES INDICATE A SIGNIFICANT ROLE OF EPIGENETIC REGULATION IN THE DEVELOPMENT OF CHRONIC COMPLICATIONS IN PATIENTS WITH DIABETES. HYPERGLYCEMIA COULD CAUSE ABNORMAL REGULATION OF THE ACTIVITY OF ENZYMES PARTICIPATING IN THE POST-TRANSLATIONAL HISTONE MODIFICATIONS (PTHMS) AND INITIATION OF CHANGES IN PATTERNS OF DNA METHYLATION. IT LEADS TO MODIFICATION OF CHROMATIN STRUCTURE. THESE EPIGENETIC ABNORMALITIES RESULT IN CHANGES IN THE EXPRESSION OF GENES INVOLVED IN DEVELOPMENT OF CHRONIC INFLAMMATION, SUCH AS NF-KAPPAB (NUCLEAR FACTOR KAPPAB GENE), TNFALPHA (TUMOR NECROSIS FACTOR A GENE), IL6 (INTERLEUKIN 6 GENE) OR MCP1 (MONOCYTE CHEMOATTRACTANT PROTEIN 1 GENE). IT ENHANCES ENDOTHELIAL CELL DYSFUNCTION, WHICH PLAYS AN IMPORTANT ROLE IN DEVELOPMENT OF CHRONIC, DIABETIC COMPLICATIONS. IN ADDITION, CAUSED BY HYPERGLYCEMIA EPIGENETIC MODIFICATIONS CHANGES IN STRUCTURE OF CHROMATIN EXPLAINS "METABOLIC MEMORY", A PHENOMENON OF PRESENCE OF PATHOLOGICAL PATHWAYS RELATED TO THE PROLONGED HYPERGLYCEMIA IN THE PAST, DESPITE MAINTAINING GOOD METABOLIC CONTROL LATER ON. 2015 20 1974 35 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