1 5546 122 ROLE OF EPIGENETIC MECHANISMS IN THE DEVELOPMENT OF CHRONIC COMPLICATIONS OF DIABETES. THERE IS GROWING EVIDENCE THAT EPIGENETIC REGULATION OF GENE EXPRESSION INCLUDING POST-TRANSLATIONAL HISTONE MODIFICATIONS (PTHMS), DNA METHYLATION AND MICRORNA (MIRNA)-REGULATION OF MRNA TRANSLATION COULD PLAY A CRUCIAL ROLE IN THE DEVELOPMENT OF CHRONIC, DIABETIC COMPLICATIONS. HYPERGLYCEMIA CAN INDUCE AN ABNORMAL ACTION OF PTHMS AND DNA METHYLTRANSFERASES AS WELL AS ALTER THE LEVELS OF NUMEROUS MIRNAS IN ENDOTHELIAL CELLS, VASCULAR SMOOTH MUSCLE CELLS, CARDIOMYOCYTES, RETINA, AND RENAL CELLS. THESE EPIGENETIC ABNORMALITIES RESULT IN CHANGES IN THE EXPRESSION OF NUMEROUS GENES CONTRIBUTING TO EFFECTS SUCH AS DEVELOPMENT OF CHRONIC INFLAMMATION, IMPAIRED CLEARANCE OF REACTIVE OXYGEN SPECIES (ROS), ENDOTHELIAL CELL DYSFUNCTION AND/OR THE ACCUMULATION OF EXTRACELLULAR MATRIX IN THE KIDNEY, WHICH CAUSING THE DEVELOPMENT OF RETINOPATHY, NEPHROPATHY OR CARDIOMYOPATHY. SOME EPIGENETIC MODIFICATIONS, FOR EXAMPLE PTHMS AND DNA METHYLATION, BECOME IRREVERSIBLE OVER TIME. THEREFORE, THESE PROCESSES HAVE GAINED MUCH ATTENTION IN EXPLAINING THE LONG-LASTING DETRIMENTAL CONSEQUENCES OF HYPERGLYCAEMIA CAUSING THE DEVELOPMENT OF CHRONIC COMPLICATIONS EVEN AFTER IMPROVED GLYCAEMIC CONTROL IS ACHIEVED. OUR REVIEW SUGGESTS THAT THE TREATMENT OF CHRONIC COMPLICATIONS SHOULD FOCUS ON ERASING METABOLIC MEMORY BY TARGETING CHROMATIN MODIFICATION ENZYMES AND BY RESTORING MIRNA LEVELS. 2014 2 6902 52 [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 3 2613 54 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 4 607 43 BEYOND GENETICS: EPIGENETIC CODE IN CHRONIC KIDNEY DISEASE. EPIGENETICS REFERS TO A HERITABLE CHANGE IN THE PATTERN OF GENE EXPRESSION THAT IS MEDIATED BY A MECHANISM SPECIFICALLY NOT DUE TO ALTERATIONS IN THE PRIMARY NUCLEOTIDE SEQUENCE. WELL-KNOWN EPIGENETIC MECHANISMS ENCOMPASS DNA METHYLATION, CHROMATIN REMODELING (HISTONE MODIFICATIONS), AND RNA INTERFERENCE. FUNCTIONALLY, EPIGENETICS PROVIDES AN EXTRA LAYER OF TRANSCRIPTIONAL CONTROL AND PLAYS A CRUCIAL ROLE IN NORMAL PHYSIOLOGICAL DEVELOPMENT, AS WELL AS IN PATHOLOGICAL CONDITIONS. ABERRANT DNA METHYLATION IS IMPLICATED IN IMMUNE DYSFUNCTION, INFLAMMATION, AND INSULIN RESISTANCE. EPIGENETIC CHANGES MAY BE RESPONSIBLE FOR 'METABOLIC MEMORY' AND DEVELOPMENT OF MICRO- AND MACROVASCULAR COMPLICATIONS OF DIABETES. MICRORNAS ARE CRITICAL IN THE MAINTENANCE OF GLOMERULAR HOMEOSTASIS AND HENCE RNA INTERFERENCE MAY BE IMPORTANT IN THE PROGRESSION OF RENAL DISEASE. RECENT STUDIES HAVE SHOWN THAT EPIGENETIC MODIFICATIONS ORCHESTRATE THE EPITHELIAL-MESENCHYMAL TRANSITION AND EVENTUALLY FIBROSIS OF THE RENAL TISSUE. OXIDATIVE STRESS, INFLAMMATION, HYPERHOMOCYSTEINEMIA, AND UREMIC TOXINS COULD INDUCE EPIMUTATIONS IN CHRONIC KIDNEY DISEASE. EPIGENETIC ALTERATIONS ARE ASSOCIATED WITH INFLAMMATION AND CARDIOVASCULAR DISEASE IN PATIENTS WITH CHRONIC KIDNEY DISEASE. REVERSIBLE NATURE OF THE EPIGENETIC CHANGES GIVES A UNIQUE OPPORTUNITY TO HALT OR EVEN REVERSE THE DISEASE PROCESS THROUGH TARGETED THERAPEUTIC STRATEGIES. 2011 5 3156 41 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 6 4336 38 MICRORNAS: THE UNDERLYING MEDIATORS OF PATHOGENETIC PROCESSES IN VASCULAR COMPLICATIONS OF DIABETES. DIABETES MELLITUS CAUSES CHRONIC COMPLICATIONS PRIMARILY AFFECTING THE VASCULATURE OF VARIOUS ORGANS, RISKING PATIENTS FOR RENAL FAILURE, VISION LOSS AND HEART FAILURE. A NEWLY DISCOVERED CLASS OF MOLECULES, MICRORNAS, MAY BE IMPORTANT IN THE GENESIS OF THESE PATHOLOGIC PROCESSES. MICRORNAS REGULATE GENE EXPRESSION AT THE POST-TRANSCRIPTIONAL LEVEL BY INHIBITING TARGET MESSENGER RNA TRANSLATION. IN DISEASE STATES, HOWEVER, THE EXPRESSION OF MICRORNAS OFTEN IS ALTERED, RESULTING IN FURTHER ALTERED EXPRESSION (MOSTLY OVEREXPRESSION) OF DOWNSTREAM TARGET GENES. INTERESTINGLY, RESTORING MICRORNA EXPRESSION TO NORMAL LEVELS CAN CORRECT DOWNSTREAM EFFECTS AND PREVENT DIABETES-ASSOCIATED CHANGES. INVESTIGATIONS INTO MICRORNA INVOLVED IN VARIOUS PATHOGENETIC PROCESSES MEDIATING DIABETIC NEPHROPATHY, RETINOPATHY AND CARDIOMYOPATHY ARE HIGHLIGHTED IN THIS REVIEW. FUTURE DIRECTIONS OF MICRORNA IN THERAPEUTICS AND DIAGNOSTICS ARE ALSO DISCUSSED. IT IS OUR INTENT TO HELP THE READER APPRECIATE THE DIVERSE INTERACTIONS MICRORNAS HAVE IN CELLULAR SIGNALLING AND HOW UNDERSTANDING EPIGENETIC ELEMENTS, SUCH AS MICRORNAS, POTENTIALLY CAN YIELD NEW THERAPEUTIC STRATEGIES. 2013 7 6129 47 THE EPIGENETIC REGULATION OF PODOCYTE FUNCTION IN DIABETES. CHRONIC HYPERGLYCEMIA EARLY IN THE COURSE OF DIABETES CONFERS A SUSTAINED INCREASE IN THE RISK OF COMPLICATIONS DEVELOPMENT. IN RECENT YEARS, EFFORTS TO UNDERSTAND THE MOLECULAR BASIS FOR THIS "METABOLIC MEMORY" HAVE FOCUSED ON EPIGENETIC MECHANISMS AS A MEANS BY WHICH TRANSIENT HIGH GLUCOSE CAN CAUSE PERSISTENT AND PROPAGATED CHANGES IN CELL FUNCTION. FOR INSTANCE, IN VASCULAR ENDOTHELIAL CELLS, SMOOTH MUSCLE CELLS AND PERIPHERAL BLOOD CELLS, TEMPORARY EXPOSURE TO HIGH GLUCOSE CAUSES CHANGES IN EPIGENETIC MARKS THAT PROMOTE A SHIFT TOWARDS A PRO-INFLAMMATORY PHENOTYPE. HOWEVER, THE INFLUENCE OF EPIGENETIC PROCESSES IN COMPLICATIONS DEVELOPMENT EXTENDS BEYOND THEIR CONTRIBUTION TO METABOLIC MEMORY. PODOCYTES, FOR EXAMPLE, ARE TERMINALLY DIFFERENTIATED CELLS OF THE RENAL GLOMERULUS WHOSE INJURY IS A MAJOR CONTRIBUTOR TO THE PATHOGENESIS OF NEPHROPATHY. OVER RECENT MONTHS, SEVERAL REPORTS HAVE EMERGED DESCRIBING THE ESSENTIAL ACTIONS OF HISTONE-MODIFYING ENZYMES AND DNA METHYLATION PATTERNS (THE TWO PRINCIPAL EPIGENETIC MECHANISMS) IN MAINTAINING PODOCYTE INTEGRITY, ESPECIALLY UNDER DIABETIC CONDITIONS. HERE, WE REVIEW THE KNOWN AND POTENTIAL ROLE OF EPIGENETIC PROCESSES WITHIN PODOCYTES, FOCUSING ON THE EVIDENCE LINKING THESE PROCESSES TO OXIDATIVE STRESS, CROSSTALK WITH TUBULE CELLS, AUTOPHAGY AND SLIT-PORE PROTEIN EXPRESSION. WHETHER PODOCYTES THEMSELVES EXHIBIT A METABOLIC MEMORY AWAITS TO BE SEEN. 2015 8 6341 39 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 9 2163 44 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 10 1487 35 DNA DAMAGE AND EPIGENETIC CHANGES IN KIDNEY DISEASES - FOCUSED ON TRANSCRIPTION FACTORS IN PODOCYTES. RECENTLY IT HAS BEEN SHOWN THAT EPIGENETIC MECHANISMS ARE INVOLVED IN INITIATION AND PROGRESSION OF CARIDIOVASCULAR AND METABOLIC DISEASES, INCLUDING DIABETES, OBESITY, ATHEROSCLEROSIS, HEART FAILURE, HYPERTENSION AND KIDNEY DISEASES. IN THESE CHRONIC DISEASES, VARIOUS EXOGENOUS AND ENDOGENOUS STRESSES CAUSE DNA DAMAGE, FOLLOWED BY DNA REPAIR PROCESS. ACCUMULATION OF DNA DAMAGES AND IMPAIRED REPAIR PROCESS CAN LEAD TO EPIGENETIC CHANGES, WHICH MAY CONTRIBUTE TO ONSET AND PROGRESSION OF DISEASES. RECENTLY WE HAVE SHOWN THAT THERAPEUTIC EFFECT OF TRANSCRIPTION FACTOR KLF4 (KRUPPEL-LIKE FACTOR 4) IN KIDNEY GLOMERULAR EPITHELIAL CELLS (PODOCYTES) ON PROTEINURIC KIDNEY DISEASES THROUGH EPIGENETIC MECHANISMS. OUR RESULT SUGGESTS THE POSSIBILITY OF TRANSCRIPTION FACTORS AS A TARGET OF SELECTIVE EPIGENETIC THERAPY. MOREOVER, WE HAVE REPORTED THAT RENIN-ANGIOTENSIN SYSTEM (RAS) BLOCKERS, WHICH ARE WIDELY PRESCRIBED FOR THE TREATMENT OF CARDIOVASCULAR DISEASES, CAN RESTORE EPIGENETIC CHANGES THROUGH KLF4 IN PART. THESE RESULTS SUGGEST THAT ACTIVATION OF RAS CAUSES EPIGENETIC CHANGES IN DISEASE STATES, AND ELUCIDATION OF THE PRECISE MECHANISM MAY LEAD TO ESTABLISHMENT OF NOVEL THERAPEUTIC TARGET OF KIDNEY DISEASES. IN THIS REVIEW WE FOCUS ON DNA DAMAGE REPAIR SYSTEM AND EPIGENETIC MODULATORS IN DISEASE STATES, AND SPECULATE A CANDIDATE FOR EPIGENETIC THERAPY OF KIDNEY DISEASES. 2016 11 2206 40 EPIGENETIC MODIFICATIONS AND DIABETIC RETINOPATHY. DIABETIC RETINOPATHY REMAINS ONE OF THE MOST DEBILITATING CHRONIC COMPLICATIONS, BUT DESPITE EXTENSIVE RESEARCH IN THE FIELD, THE EXACT MECHANISM(S) RESPONSIBLE FOR HOW RETINA IS DAMAGED IN DIABETES REMAINS AMBIGUOUS. MANY METABOLIC PATHWAYS HAVE BEEN IMPLICATED IN ITS DEVELOPMENT, AND GENES ASSOCIATED WITH THESE PATHWAYS ARE ALTERED. DIABETIC ENVIRONMENT ALSO FACILITATES EPIGENETICS MODIFICATIONS, WHICH CAN ALTER THE GENE EXPRESSION WITHOUT PERMANENT CHANGES IN DNA SEQUENCE. THE ROLE OF EPIGENETICS IN DIABETIC RETINOPATHY IS NOW AN EMERGING AREA, AND RECENT WORK HAS SHOWN THAT GENES ENCODING MITOCHONDRIAL SUPEROXIDE DISMUTASE (SOD2) AND MATRIX METALLOPROTEINASE-9 (MMP-9) ARE EPIGENETICALLY MODIFIED, ACTIVATES OF EPIGENETIC MODIFICATION ENZYMES, HISTONE LYSINE DEMETHYLASE 1 (LSD1), AND DNA METHYLTRANSFERASE ARE INCREASED, AND THE MICRO RNAS RESPONSIBLE FOR REGULATING NUCLEAR TRANSCRIPTIONAL FACTOR AND VEGF ARE UPREGULATED. WITH THE GROWING EVIDENCE OF EPIGENETIC MODIFICATIONS IN DIABETIC RETINOPATHY, BETTER UNDERSTANDING OF THESE MODIFICATIONS HAS POTENTIAL TO IDENTIFY NOVEL TARGETS TO INHIBIT THIS DEVASTATING DISEASE. FORTUNATELY, THE INHIBITORS AND MIMICS TARGETED TOWARDS HISTONE MODIFICATION, DNA METHYLATION, AND MIRNAS ARE NOW BEING TRIED FOR CANCER AND OTHER CHRONIC DISEASES, AND BETTER UNDERSTANDING OF THE ROLE OF EPIGENETICS IN DIABETIC RETINOPATHY WILL OPEN THE DOOR FOR THEIR POSSIBLE USE IN COMBATING THIS BLINDING DISEASE. 2013 12 2965 49 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 13 2195 40 EPIGENETIC MODIFICATION MECHANISMS INVOLVED IN INFLAMMATION AND FIBROSIS IN RENAL PATHOLOGY. THE GROWING INCIDENCE OF OBESITY, HYPERTENSION, AND DIABETES, COUPLED WITH THE AGING OF THE POPULATION, IS INCREASING THE PREVALENCE OF RENAL DISEASES IN OUR SOCIETY. CHRONIC KIDNEY DISEASE (CKD) IS CHARACTERIZED BY PERSISTENT INFLAMMATION, FIBROSIS, AND LOSS OF RENAL FUNCTION LEADING TO END-STAGE RENAL DISEASE. NOWADAYS, CKD TREATMENT HAS LIMITED EFFECTIVENESS UNDERSCORING THE IMPORTANCE OF THE DEVELOPMENT OF INNOVATIVE THERAPEUTIC OPTIONS. RECENT STUDIES HAVE IDENTIFIED HOW EPIGENETIC MODIFICATIONS PARTICIPATE IN THE SUSCEPTIBILITY TO CKD AND HAVE EXPLAINED HOW THE ENVIRONMENT INTERACTS WITH THE RENAL CELL EPIGENOME TO CONTRIBUTE TO RENAL DAMAGE. EPIGENETIC MECHANISMS REGULATE CRITICAL PROCESSES INVOLVED IN GENE REGULATION AND DOWNSTREAM CELLULAR RESPONSES. THE MOST RELEVANT EPIGENETIC MODIFICATIONS THAT PLAY A CRITICAL ROLE IN RENAL DAMAGE INCLUDE DNA METHYLATION, HISTONE MODIFICATIONS, AND CHANGES IN MIRNA LEVELS. IMPORTANTLY, THESE EPIGENETIC MODIFICATIONS ARE REVERSIBLE AND, THEREFORE, A SOURCE OF POTENTIAL THERAPEUTIC TARGETS. HERE, WE WILL EXPLAIN HOW EPIGENETIC MECHANISMS MAY REGULATE ESSENTIAL PROCESSES INVOLVED IN RENAL PATHOLOGY AND HIGHLIGHT SOME POSSIBLE EPIGENETIC THERAPEUTIC STRATEGIES FOR CKD TREATMENT. 2018 14 3826 40 INVESTIGATION OF EPIGENETICS IN KIDNEY CELL BIOLOGY. EPIGENETICS IS THE STUDY OF HERITABLE CHANGES IN DNA OR ITS ASSOCIATED PROTEINS EXCEPT MUTATIONS IN GENE SEQUENCE. EPIGENETIC REGULATION PLAYS FUNDAMENTAL ROLES IN THE PROCESSES OF KIDNEY CELL BIOLOGY THROUGH THE ACTION OF DNA METHYLATION, CHROMATIN MODIFICATIONS VIA EPIGENETIC REGULATORS AND INTERACTION VIA TRANSCRIPTION FACTORS, AND NONCODING RNA SPECIES. KIDNEY DISEASES, INCLUDING ACUTE KIDNEY INJURY, CHRONIC KIDNEY DISEASE, NEPHRITIC AND NEPHROTIC SYNDROMES, PYELONEPHRITIS AND POLYCYSTIC KIDNEY DISEASES ARE DRIVEN BY ABERRANT ACTIVITY IN NUMEROUS SIGNALING PATHWAYS IN EVEN INDIVIDUAL KIDNEY CELL. EPIGENETIC ALTERATIONS, INCLUDING DNA METHYLATION, HISTONE ACETYLATION AND METHYLATION, NONCODING RNAS, AND PROTEIN POSTTRANSLATIONAL MODIFICATIONS, COULD DISRUPT ESSENTIAL PATHWAYS THAT PROTECT THE RENAL CELLS FROM UNCONTROLLED GROWTH, APOPTOSIS AND ESTABLISHMENT OF OTHER RENAL ASSOCIATED SYNDROMES, WHICH HAVE BEEN RECOGNIZED AS ONE OF THE CRITICAL MECHANISMS FOR REGULATING FUNCTIONAL CHANGES THAT DRIVE AND MAINTAIN THE KIDNEY DISEASE PHENOTYPE. IN THIS CHAPTER, WE BRIEFLY SUMMARIZE THE EPIGENETIC MECHANISMS IN KIDNEY CELL BIOLOGY AND EPIGENETIC BASIS OF KIDNEY DEVELOPMENT, AND INTRODUCE EPIGENETIC TECHNIQUES THAT CAN BE USED IN INVESTIGATING THE MOLECULAR MECHANISM OF KIDNEY CELL BIOLOGY AND KIDNEYS DISEASES, PRIMARILY FOCUSING ON THE INTEGRATION OF DNA METHYLATION AND CHROMATIN IMMUNOPRECIPITATION TECHNOLOGIES INTO KIDNEY DISEASE ASSOCIATED STUDIES. FUTURE STUDIES USING THESE EMERGING TECHNOLOGIES WILL ELUCIDATE HOW ALTERATIONS IN THE RENAL CELL EPIGENOME COOPERATE WITH GENETIC ABERRATIONS FOR KIDNEY DISEASE INITIATION AND PROGRESSION. INCORPORATING EPIGENOMIC TESTING INTO THE CLINICAL RESEARCH IS ESSENTIAL TO FUTURE STUDIES WITH EPIGENETICS BIOMARKERS AND PRECISION MEDICINE USING EMERGING EPIGENETIC THERAPIES. 2019 15 4668 34 NEW INSIGHTS INTO MOLECULAR MECHANISMS OF EPIGENETIC REGULATION IN KIDNEY DISEASE. THE NUMBER OF PATIENTS WITH KIDNEY FAILURE HAS INCREASED IN RECENT YEARS. DIFFERENT FACTORS CONTRIBUTE TO THE PROGRESSION OF CHRONIC KIDNEY DISEASE, INCLUDING GLOMERULAR SCLEROSIS, ATHEROSCLEROSIS OF THE RENAL ARTERIES AND TUBULOINTERSTITIAL FIBROSIS. TUBULOINTERSTITIAL INJURY IS INDUCED BY HYPOXIA AND OTHER INFLAMMATORY SIGNALS, LEADING TO FIBROBLAST ACTIVATION. TECHNOLOGICAL ADVANCES USING HIGH-THROUGHPUT SEQUENCING HAS ENABLED THE DETERMINATION OF THE EXPRESSION PROFILE OF ALMOST ALL GENES, REVEALING THAT GENE EXPRESSION IS INTRICATELY REGULATED BY DNA METHYLATION, HISTONE MODIFICATION, CHANGES IN CHROMOSOME CONFORMATION, LONG NON-CODING RNAS AND MICRORNAS. THESE EPIGENETIC MODIFICATIONS ARE STORED AS CELLULAR EPIGENETIC MEMORY. EPIGENETIC MEMORY LEADS TO ADULT-ONSET DISEASE OR AGEING IN THE LONG TERM AND MAY POSSIBLY PLAY AN IMPORTANT ROLE IN THE KIDNEY DISEASE PROCESS. HEREIN WE EMPHASIZE THE IMPORTANCE OF CLARIFYING THE MOLECULAR MECHANISMS UNDERLYING EPIGENETIC MODIFICATIONS BECAUSE THIS MAY LEAD TO THE DEVELOPMENT OF NEW THERAPEUTIC TARGETS IN KIDNEY DISEASE. 2016 16 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 17 1505 34 DNA METHYLATION AND HISTONE MODIFICATION IN HYPERTENSION. SYSTEMIC HYPERTENSION, WHICH EVENTUALLY RESULTS IN HEART FAILURE, RENAL FAILURE OR STROKE, IS A COMMON CHRONIC HUMAN DISORDER THAT PARTICULARLY AFFECTS ELDERS. ALTHOUGH MANY SIGNALING PATHWAYS INVOLVED IN THE DEVELOPMENT OF HYPERTENSION HAVE BEEN REPORTED OVER THE PAST DECADES, WHICH HAS LED TO THE IMPLEMENTATION OF A WIDE VARIETY OF ANTI-HYPERTENSIVE THERAPIES, ONE HALF OF ALL HYPERTENSIVE PATIENTS STILL DO NOT HAVE THEIR BLOOD PRESSURE CONTROLLED. THE FRONTIER IN UNDERSTANDING THE MOLECULAR MECHANISMS UNDERLYING HYPERTENSION HAS NOW ADVANCED TO THE LEVEL OF EPIGENOMICS. PARTICULARLY, INCREASING EVIDENCE IS EMERGING THAT DNA METHYLATION AND HISTONE MODIFICATIONS PLAY AN IMPORTANT ROLE IN GENE REGULATION AND ARE INVOLVED IN ALTERATION OF THE PHENOTYPE AND FUNCTION OF VASCULAR CELLS IN RESPONSE TO ENVIRONMENTAL STRESSES. THIS REVIEW SEEKS TO HIGHLIGHT THE RECENT ADVANCES IN OUR KNOWLEDGE OF THE EPIGENETIC REGULATIONS AND MECHANISMS OF HYPERTENSION, FOCUSING ON THE ROLE OF DNA METHYLATION AND HISTONE MODIFICATION IN THE VASCULAR WALL. A BETTER UNDERSTANDING OF THE EPIGENOMIC REGULATION IN THE HYPERTENSIVE VESSEL MAY LEAD TO THE IDENTIFICATION OF NOVEL TARGET MOLECULES THAT, IN TURN, MAY LEAD TO NOVEL DRUG DISCOVERIES FOR THE TREATMENT OF HYPERTENSION. 2018 18 2609 36 EPIGENETICS: A POTENTIAL KEY MECHANISM INVOLVED IN THE PATHOGENESIS OF CARDIORENAL SYNDROMES. EPIGENETICS IS DEFINED AS THE HERITABLE CHANGES IN GENE EXPRESSION PATTERNS WHICH ARE NOT DIRECTLY ENCODED BY MODIFICATIONS IN THE NUCLEOTIDE DNA SEQUENCE OF THE GENOME, INCLUDING HIGHER ORDER CHROMATIN ORGANIZATION, DNA METHYLATION, CYTOSINE MODIFICATIONS, COVALENT HISTONE TAIL MODIFICATIONS, AND SHORT NON-CODING RNA MOLECULES. RECENTLY, MUCH ATTENTION HAS BEEN PAID TO THE ROLE AND THE FUNCTION OF EPIGENETICS AND EPIMUTATIONS IN THE CELLULAR AND SUBCELLULAR PATHWAYS AND IN THE REGULATION OF GENES IN THE SETTING OF BOTH KIDNEY AND CARDIOVASCULAR DISEASE. INDEED, DEREGULATION OF HISTONE ALTERATIONS HAS BEEN HIGHLIGHTED IN A LARGE SPECTRUM OF RENAL AND CARDIAC DISEASE, INCLUDING CHRONIC AND ACUTE RENAL INJURY, RENAL AND CARDIAC FIBROSIS, CARDIAC HYPERTROPHY AND FAILURE, KIDNEY CONGENITAL ANOMALIES, RENAL HYPOXIA, AND DIABETIC RENAL COMPLICATIONS. NEVERTHELESS, THE ROLE OF EPIGENETICS IN THE PATHOGENESIS AND PATHOPHYSIOLOGY OF CARDIORENAL SYNDROMES IS CURRENTLY UNDEREXPLORED. GIVEN THE SIGNIFICANT CLINICAL RELEVANCE OF HEART-KIDNEY CROSSTALK, EFFORTS IN THE RESEARCH FOR NEW ACTION MECHANISMS CONCURRENTLY OPERATING IN BOTH PATHOLOGIES ARE THUS OF MAXIMUM INTEREST. THIS REVIEW FOCUSES ON EPIGENETIC MECHANISMS INVOLVED IN HEART AND KIDNEY DISEASE, AND THEIR POSSIBLE ROLE IN THE SETTING OF CARDIORENAL SYNDROMES. 2018 19 2549 38 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 20 6377 37 THE ROLE OF NON-CODING RNAS IN DIABETIC NEPHROPATHY: POTENTIAL APPLICATIONS AS BIOMARKERS FOR DISEASE DEVELOPMENT AND PROGRESSION. DIABETIC NEPHROPATHY, A PROGRESSIVE KIDNEY DISEASE THAT DEVELOPS SECONDARY TO DIABETES, IS THE MAJOR CAUSE OF CHRONIC KIDNEY DISEASE IN DEVELOPED COUNTRIES, AND CONTRIBUTES SIGNIFICANTLY TO INCREASED MORBIDITY AND MORTALITY AMONG INDIVIDUALS WITH DIABETES. ALTHOUGH THE CAUSES OF DIABETIC NEPHROPATHY ARE NOT FULLY UNDERSTOOD, RECENT STUDIES DEMONSTRATE A ROLE FOR EPIGENETIC FACTORS IN THE DEVELOPMENT OF THE DISEASE. FOR EXAMPLE, NON-CODING RNA (NCRNA) MOLECULES, INCLUDING MICRORNAS (MIRNAS), HAVE BEEN SHOWN TO BE FUNCTIONALLY IMPORTANT IN MODULATING RENAL RESPONSE TO HYPERGLYCEMIA AND PROGRESSION OF DIABETIC NEPHROPATHY. CHARACTERIZATION OF MIRNA EXPRESSION IN DIABETIC NEPHROPATHY FROM STUDIES OF ANIMAL MODELS OF DIABETES, AND IN VITRO INVESTIGATIONS USING DIFFERENT TYPES OF KIDNEY CELLS ALSO SUPPORT THIS ROLE. THE GOAL OF THIS REVIEW, THEREFORE, IS TO SUMMARIZE THE CURRENT STATE OF KNOWLEDGE OF SPECIFIC NCRNAS INVOLVED IN THE DEVELOPMENT OF DIABETIC NEPHROPATHY, WITH A FOCUS ON THE POTENTIAL ROLE OF MIRNAS TO SERVE AS SENSITIVE, NON-INVASIVE BIOMARKERS OF KIDNEY DISEASE AND PROGRESSION. NON-CODING RNAS ARE CURRENTLY RECOGNIZED AS POTENTIALLY IMPORTANT REGULATORS OF GENES INVOLVED IN PROCESSES RELATED TO THE DEVELOPMENT OF DIABETIC NEPHROPATHY, AND AS SUCH, REPRESENT VIABLE TARGETS FOR BOTH CLINICAL DIAGNOSTIC STRATEGIES AND THERAPEUTIC INTERVENTION. 2013