1 5363 65 RECENT ADVANCES IN DIABETIC KIDNEY DISEASES: FROM KIDNEY INJURY TO KIDNEY FIBROSIS. DIABETIC KIDNEY DISEASE (DKD) IS THE LEADING CAUSE OF CHRONIC KIDNEY DISEASE AND END-STAGE RENAL DISEASE. THE NATURAL HISTORY OF DKD INCLUDES GLOMERULAR HYPERFILTRATION, PROGRESSIVE ALBUMINURIA, DECLINING ESTIMATED GLOMERULAR FILTRATION RATE, AND, ULTIMATELY, KIDNEY FAILURE. IT IS KNOWN THAT DKD IS ASSOCIATED WITH METABOLIC CHANGES CAUSED BY HYPERGLYCEMIA, RESULTING IN GLOMERULAR HYPERTROPHY, GLOMERULOSCLEROSIS, AND TUBULOINTERSTITIAL INFLAMMATION AND FIBROSIS. HYPERGLYCEMIA IS ALSO KNOWN TO CAUSE PROGRAMMED EPIGENETIC MODIFICATION. HOWEVER, THE DETAILED MECHANISMS INVOLVED IN THE ONSET AND PROGRESSION OF DKD REMAIN ELUSIVE. IN THIS REVIEW, WE DISCUSS RECENT ADVANCES REGARDING THE PATHOGENIC MECHANISMS INVOLVED IN DKD. 2021 2 6575 29 TREATMENT OF DIABETIC KIDNEY DISEASE: CURRENT AND FUTURE. DIABETIC KIDNEY DISEASE (DKD) IS THE MAJOR CAUSE OF END-STAGE KIDNEY DISEASE. HOWEVER, ONLY RENIN-ANGIOTENSIN SYSTEM INHIBITOR WITH MULTIDISCIPLINARY TREATMENTS IS EFFECTIVE FOR DKD. IN 2019, SODIUM-GLUCOSE COTRANSPORTER 2 (SGLT2) INHIBITOR SHOWED EFFICACY AGAINST DKD IN CANAGLIFLOZIN AND RENAL EVENTS IN DIABETES WITH ESTABLISHED NEPHROPATHY CLINICAL EVALUATION (CREDENCE) TRIAL, ADDING A NEW TREATMENT OPTION. HOWEVER, THE PROGRESSION OF DKD HAS NOT BEEN COMPLETELY CONTROLLED. THE PATIENTS WITH TRANSIENT EXPOSURE TO HYPERGLYCEMIA DEVELOP DIABETIC COMPLICATIONS, INCLUDING DKD, EVEN AFTER NORMALIZATION OF THEIR BLOOD GLUCOSE. TEMPORARY HYPERGLYCEMIA CAUSES ADVANCED GLYCATION END PRODUCT (AGE) ACCUMULATIONS AND EPIGENETIC CHANGES AS METABOLIC MEMORY. THE DRUGS THAT IMPROVE METABOLIC MEMORY ARE AWAITED, AND AGE INHIBITORS AND HISTONE MODIFICATION INHIBITORS ARE THE FOCUS OF CLINICAL AND BASIC RESEARCH. IN ADDITION, INCRETIN-RELATED DRUGS SHOWED A RENOPROTECTIVE ABILITY IN MANY CLINICAL TRIALS, AND THESE TRIALS WITH RENAL OUTCOME AS THEIR PRIMARY ENDPOINT ARE CURRENTLY ONGOING. HYPOXIA-INDUCIBLE FACTOR PROLYL HYDROXYLASE INHIBITORS RECENTLY APPROVED FOR RENAL ANEMIA MAY BE RENOPROTECTIVE SINCE THEY IMPROVE TUBULOINTERSTITIAL HYPOXIA. FURTHERMORE, NF-E2-RELATED FACTOR 2 ACTIVATORS IMPROVED THE GLOMERULAR FILTRATION RATE OF DKD PATIENTS IN BARDOXOLONE METHYL TREATMENT: RENAL FUNCTION IN CHRONIC KIDNEY DISEASE/TYPE 2 DIABETES (BEAM) TRIAL AND PHASE II STUDY OF BARDOXOLONE METHYL IN PATIENTS WITH CHRONIC KIDNEY DISEASE AND TYPE 2 DIABETES (TSUBAKI) TRIAL. THUS, FOLLOWING SGLT2 INHIBITOR, NUMEROUS NOVEL DRUGS COULD BE UTILIZED IN TREATING DKD. FUTURE STUDIES ARE EXPECTED TO PROVIDE NEW INSIGHTS. 2021 3 4137 22 MECHANISMS OF METABOLIC MEMORY AND RENAL HYPOXIA AS A THERAPEUTIC TARGET IN DIABETIC KIDNEY DISEASE. DIABETIC KIDNEY DISEASE (DKD) IS A WORLDWIDE PUBLIC HEALTH PROBLEM. THE DEFINITION OF DKD IS UNDER DISCUSSION. ALTHOUGH THE TERM DKD WAS ORIGINALLY DEFINED AS 'KIDNEY DISEASE SPECIFIC TO DIABETES,' DKD FREQUENTLY MEANS CHRONIC KIDNEY DISEASE WITH DIABETES MELLITUS AND INCLUDES NOT ONLY CLASSICAL DIABETIC NEPHROPATHY, BUT ALSO KIDNEY DYSFUNCTION AS A RESULT OF NEPHROSCLEROSIS AND OTHER CAUSES. METABOLIC MEMORY PLAYS A CRUCIAL ROLE IN THE PROGRESSION OF VARIOUS COMPLICATIONS OF DIABETES, INCLUDING DKD. THE MECHANISMS OF METABOLIC MEMORY IN DKD ARE SUPPOSED TO INCLUDE ADVANCED GLYCATION END-PRODUCTS, DEOXYRIBONUCLEIC ACID METHYLATION, HISTONE MODIFICATIONS AND NON-CODING RIBONUCLEIC ACID INCLUDING MICRO RIBONUCLEIC ACID. REGARDLESS OF THE PRESENCE OF DIABETES MELLITUS, THE FINAL COMMON PATHWAY IN CHRONIC KIDNEY DISEASE IS CHRONIC KIDNEY HYPOXIA, WHICH INFLUENCES EPIGENETIC PROCESSES, INCLUDING DEOXYRIBONUCLEIC ACID METHYLATION, HISTONE MODIFICATION, AND CONFORMATIONAL CHANGES IN MICRO RIBONUCLEIC ACID AND CHROMATIN. THEREFORE, HYPOXIA AND OXIDATIVE STRESS ARE APPROPRIATE TARGETS OF THERAPIES AGAINST DKD. PROLYL HYDROXYLASE DOMAIN INHIBITOR ENHANCES THE DEFENSIVE MECHANISMS AGAINST HYPOXIA. BARDOXOLONE METHYL PROTECTS AGAINST OXIDATIVE STRESS, AND CAN EVEN REVERSE IMPAIRED RENAL FUNCTION; A PHASE 2 TRIAL WITH CONSIDERABLE ATTENTION TO HEART COMPLICATIONS IS CURRENTLY ONGOING IN JAPAN. 2017 4 1983 28 EPIGENETIC ALTERATIONS IN PODOCYTES IN DIABETIC NEPHROPATHY. RECENTLY, EPIGENETIC ALTERATIONS HAVE BEEN SHOWN TO BE INVOLVED IN THE PATHOGENESIS OF DIABETES AND ITS COMPLICATIONS. KIDNEY PODOCYTES, WHICH ARE GLOMERULAR EPITHELIAL CELLS, ARE IMPORTANT CELLS THAT FORM A SLIT MEMBRANE-A BARRIER FOR PROTEINURIA. PODOCYTES ARE TERMINALLY DIFFERENTIATED CELLS WITHOUT CELL DIVISION OR REPLENISHMENT ABILITIES. THEREFORE, PODOCYTE DAMAGE IS SUGGESTED TO BE ONE OF THE KEY FACTORS DETERMINING RENAL PROGNOSIS. RECENT STUDIES, INCLUDING OURS, SUGGEST THAT EPIGENETIC CHANGES IN PODOCYTES ARE ASSOCIATED WITH CHRONIC KIDNEY DISEASE, INCLUDING DIABETIC NEPHROPATHY. FURTHERMORE, THE ASSOCIATION BETWEEN DNA DAMAGE REPAIR AND EPIGENETIC CHANGES IN DIABETIC PODOCYTES HAS BEEN DEMONSTRATED. DETECTION OF PODOCYTE DNA DAMAGE AND EPIGENETIC CHANGES USING HUMAN SAMPLES, SUCH AS KIDNEY BIOPSY AND URINE-DERIVED CELLS, MAY BE A PROMISING STRATEGY FOR ESTIMATING KIDNEY DAMAGE AND RENAL PROGNOSES IN PATIENTS WITH DIABETES. TARGETING EPIGENETIC PODOCYTE CHANGES AND ASSOCIATED DNA DAMAGE MAY BECOME A NOVEL THERAPEUTIC STRATEGY FOR PREVENTING PROGRESSION TO END-STAGE RENAL DISEASE (ESRD) AND PROVIDE A POSSIBLE PROGNOSTIC MARKER IN DIABETIC NEPHROPATHY. THIS REVIEW SUMMARIZES RECENT ADVANCES REGARDING EPIGENETIC CHANGES, ESPECIALLY DNA METHYLATION, IN PODOCYTES IN DIABETIC NEPHROPATHY AND ADDRESSES DETECTION OF THESE ALTERATIONS IN HUMAN SAMPLES. ADDITIONALLY, WE FOCUSED ON DNA DAMAGE, WHICH IS INCREASED UNDER HIGH-GLUCOSE CONDITIONS AND ASSOCIATED WITH THE GENERATION OF EPIGENETIC CHANGES IN PODOCYTES. FURTHERMORE, EPIGENETIC MEMORY IN DIABETES IS DISCUSSED. UNDERSTANDING THE ROLE OF EPIGENETIC CHANGES IN PODOCYTES IN DIABETIC NEPHROPATHY MAY BE OF GREAT IMPORTANCE CONSIDERING THE INCREASING DIABETIC NEPHROPATHY PATIENT POPULATION IN AN AGING SOCIETY. 2021 5 6648 25 UPDATE ON DIAGNOSIS, PATHOPHYSIOLOGY, AND MANAGEMENT OF DIABETIC KIDNEY DISEASE. DIABETIC KIDNEY DISEASE (DKD) IS A CHRONIC COMPLICATION OF DIABETES MELLITUS WHICH MAY EVENTUALLY LEAD TO END-STAGE KIDNEY DISEASE (ESKD). DESPITE IMPROVEMENTS IN GLYCAEMIC CONTROL AND BLOOD PRESSURE MANAGEMENT WITH RENIN-ANGIOTENSIN-ALDOSTERONE SYSTEM (RAAS) BLOCKADE, THE CURRENT THERAPY CANNOT COMPLETELY HALT DKD PROGRESSION TO ESKD IN SOME PATIENTS. DKD IS A HETEROGENEOUS DISEASE ENTITY IN TERMS OF ITS CLINICAL MANIFESTATIONS, HISTOPATHOLOGY AND THE RATE OF PROGRESSION, WHICH MAKES IT DIFFICULT TO DEVELOP EFFECTIVE THERAPEUTICS. IT WAS FORMERLY CONSIDERED THAT ALBUMINURIA PRECEDED KIDNEY FUNCTION DECLINE IN DKD, BUT RECENT EPIDEMIOLOGICAL STUDIES REVEALED THAT A DISTINCT GROUP OF PATIENTS PRESENTED KIDNEY DYSFUNCTION WITHOUT DEVELOPING ALBUMINURIA. OTHER COMORBIDITIES, SUCH AS HYPERTENSION, OBESITY AND GOUT, ALSO AFFECT THE CLINICAL COURSE OF DKD. THE PATHOPHYSIOLOGY OF DKD IS COMPLEX AND MULTIFACTORIAL, INVOLVING BOTH METABOLIC AND HAEMODYNAMIC FACTORS. THESE INDUCE ACTIVATION OF INTRACELLULAR SIGNALLING PATHWAYS, OXIDATIVE STRESS, HYPOXIA, DYSREGULATED AUTOPHAGY AND EPIGENETIC CHANGES, WHICH RESULT IN KIDNEY INFLAMMATION AND FIBROSIS. RECENTLY, TWO GROUPS OF ANTIDIABETIC DRUGS, SODIUM-GLUCOSE COTRANSPORTER 2 (SGLT2) INHIBITORS AND GLUCAGON-LIKE PEPTIDE-1 (GLP-1) RECEPTOR AGONISTS, WERE DEMONSTRATED TO PROVIDE RENOPROTECTION ON TOP OF THEIR GLUCOSE-LOWERING EFFECTS. SEVERAL OTHER THERAPEUTIC AGENTS ARE ALSO BEING DEVELOPED AND EVALUATED IN CLINICAL TRIALS. 2021 6 6409 27 THE SIGNALING OF CELLULAR SENESCENCE IN DIABETIC NEPHROPATHY. DIABETIC NEPHROPATHY IS THE LEADING CAUSE OF CHRONIC KIDNEY DISEASE (CKD) IN WESTERN COUNTRIES. NOTABLY, IT HAS A RAPIDLY RISING PREVALENCE IN CHINA. THE PATIENTS, COMMONLY COMPLICATED WITH CARDIOVASCULAR DISEASES AND NEUROLOGIC DISORDERS, ARE AT HIGH RISK TO PROGRESS INTO END-STAGE RENAL DISEASE (ESRD) AND DEATH. HOWEVER, THE PATHOGENIC MECHANISMS OF DIABETIC NEPHROPATHY HAVE NOT BEEN DETERMINED. CELLULAR SENESCENCE, WHICH RECENTLY HAS GAINED BROAD ATTENTION, IS THOUGHT TO BE AN IMPORTANT PLAYER IN THE ONSET AND DEVELOPMENT OF DIABETIC NEPHROPATHY. IN THIS ISSUE, WE GENERALLY REVIEW THE MECHANISMS OF CELLULAR SENESCENCE IN DIABETIC NEPHROPATHY, WHICH INVOLVE TELOMERE ATTRITION, DNA DAMAGE, EPIGENETIC ALTERATIONS, MITOCHONDRIAL DYSFUNCTION, LOSS OF KLOTHO, WNT/BETA-CATENIN SIGNALING ACTIVATION, PERSISTENT INFLAMMATION, AND ACCUMULATION OF UREMIC TOXINS. MOREOVER, WE HIGHLIGHT THE POTENTIAL THERAPEUTIC TARGETS OF CELLULAR SENESCENCE IN DIABETIC NEPHROPATHY AND PROVIDE IMPORTANT CLUES FOR CLINICAL STRATEGIES. 2019 7 6051 20 THE CONTRIBUTION OF HISTONE CROTONYLATION TO TISSUE HEALTH AND DISEASE: FOCUS ON KIDNEY HEALTH. ACUTE KIDNEY INJURY (AKI) AND CHRONIC KIDNEY DISEASE (CKD) ARE THE MOST SEVERE CONSEQUENCES OF KIDNEY INJURY. THEY ARE INTERCONNECTED SYNDROMES AS CKD PREDISPOSES TO AKI AND AKI MAY ACCELERATE CKD PROGRESSION. DESPITE THEIR GROWING IMPACT ON THE GLOBAL BURDEN OF DISEASE, THERE IS NO SATISFACTORY TREATMENT FOR AKI AND CURRENT THERAPEUTIC APPROACHES TO CKD REMAIN SUBOPTIMAL. RECENT RESEARCH HAS FOCUSED ON THE THERAPEUTIC TARGET POTENTIAL OF EPIGENETIC REGULATION OF GENE EXPRESSION, INCLUDING NON-CODING RNAS AND THE COVALENT MODIFICATIONS OF HISTONES AND DNA. INDEED, SEVERAL DRUGS TARGETING HISTONE MODIFICATIONS ARE IN CLINICAL USE OR UNDERGOING CLINICAL TRIALS. ACYL-LYSINE HISTONE MODIFICATIONS (E.G. METHYLATION, ACETYLATION, AND CROTONYLATION) HAVE MODULATED EXPERIMENTAL KIDNEY INJURY. MOST RECENTLY, INCREASED HISTONE LYSINE CROTONYLATION (KCR) WAS OBSERVED DURING EXPERIMENTAL AKI AND COULD BE REPRODUCED IN CULTURED TUBULAR CELLS EXPOSED TO INFLAMMATORY STRESS TRIGGERED BY THE CYTOKINE TWEAK. THE DEGREE OF KIDNEY HISTONE CROTONYLATION WAS MODULATED BY CROTONATE AVAILABILITY AND CROTONATE SUPPLEMENTATION PROTECTED FROM NEPHROTOXIC AKI. WE NOW REVIEW THE FUNCTIONAL RELEVANCE OF HISTONE CROTONYLATION IN KIDNEY DISEASE AND OTHER PATHOPHYSIOLOGICAL CONTEXTS, AS WELL AS THE IMPLICATIONS FOR THE DEVELOPMENT OF NOVEL THERAPEUTIC APPROACHES. THESE STUDIES PROVIDE INSIGHTS INTO THE OVERALL ROLE OF HISTONE CROTONYLATION IN HEALTH AND DISEASE. 2020 8 2555 18 EPIGENETICS IN RENAL DISEASES. WITH AGING, PREVALENCE OF OBESITY, HYPERTENSION, DIABETES AND RENAL DISEASES HAVE INCREASED GLOBALLY. OVER THE LAST TWO DECADES, THE PREVALENCE OF RENAL DISEASES HAS BEEN INTENSELY INCREASING. RENAL DISEASE AND RENAL PROGRAMMING ARE REGULATED BY EPIGENETIC MODIFICATIONS LIKE DNA METHYLATION AND HISTONE MODIFICATIONS. ENVIRONMENTAL FACTORS HAVE SIGNIFICANT ROLE IN THE PATHOPHYSIOLOGY OF RENAL DISEASE PROGRESSION. UNDERSTANDING THE POTENTIAL OF EPIGENETIC REGULATION OF GENE EXPRESSION MAY BE USEFUL IN RENAL DISEASE PROGNOSIS, DIAGNOSIS AND PROVIDES NOVEL THERAPEUTIC MEASURES. IN A NUTSHELL, THIS CHAPTER TALKS ABOUT THE ROLE OF EPIGENETIC MECHANISMS-DNA METHYLATION, HISTONE MODIFICATION, AND NONCODING RNA IN DIFFERENT RENAL DISEASES. THESE INCLUDE DIABETIC KIDNEY DISEASE, DIABETIC NEPHROPATHY, RENAL FIBROSIS, ETC. 2023 9 2121 32 EPIGENETIC HISTONE MODIFICATIONS IN THE PATHOGENESIS OF DIABETIC KIDNEY DISEASE. DIABETIC KIDNEY DISEASE (DKD), AS THE MAIN COMPLICATION OF DIABETES MELLITUS, IS THE PRIMARY CAUSE OF THE END-STAGE RENAL DISEASE (ESRD) AND THE MOST COMMON CHRONIC KIDNEY DISEASE. OVERALL, 30-40% OF PATIENTS WITH TYPE 1 AND TYPE 2 DIABETES EVENTUALLY DEVELOP DKD. ALTHOUGH SOME DIABETES PATIENTS HAVE INTENSIFIED GLYCEMIC CONTROL, THEY STILL DEVELOP DIABETIC KIDNEY DISEASE. CURRENT TREATMENT METHODS CAN ALLEVIATE BUT DO NOT MARKEDLY HALT DISEASE DEVELOPMENT, RESULTING IN RENAL FAILURE AND SEVERE COMPLICATIONS, EVEN CONTRIBUTING TO ELEVATED MORBIDITY AND MORTALITY RATES. DKD IS A DISEASE WITH INTERACTIONS OF GENES AND THE ENVIRONMENT. EMERGING EVIDENCE INDICATES THAT DKD-ASSOCIATED KEY GENES ARE ALSO REGULATED BY THE EPIGENETIC MECHANISM. RECENTLY, INCREASING RESEARCHES INVOLVING CELLS AND EXPERIMENTAL ANIMALS DEMONSTRATED THAT HISTONE POST-TRANSLATIONAL MODIFICATIONS CAN MEDIATE GENE EXPRESSION, WHICH CORRELATED WITH DIABETIC KIDNEY DISEASE. NOVEL THERAPEUTIC STRATEGIES FOR EPIGENETIC EVENTS COULD BE BENEFICIAL FOR THE EARLY DETECTION AND TREATMENT OF DKD TO PREVENT IT FROM DEVELOPING INTO END-STAGE RENAL DISEASE (ESRD). IN THIS REVIEW, WE DISCUSS PRIOR FINDINGS IN THE FIELD OF HISTONE MODIFICATIONS IN DKD, ESPECIALLY HISTONE ACETYLATION AND HISTONE METHYLATION. WE THEN FOCUS ON RECENT DEVELOPMENTS IN HISTONE ACETYLATION AND METHYLATION INVOLVED IN THE PATHOGENESIS OF DKD. 2021 10 6075 29 THE DYNAMICS AND PLASTICITY OF EPIGENETICS IN DIABETIC KIDNEY DISEASE: THERAPEUTIC APPLICATIONS VIS-A-VIS. CHRONIC KIDNEY DISEASE (CKD) REFERS TO THE PHENOMENON OF PROGRESSIVE DECLINE IN THE GLOMERULAR FILTRATION RATE ACCOMPANIED BY ADVERSE CONSEQUENCES, INCLUDING FLUID RETENTION, ELECTROLYTE IMBALANCE, AND AN INCREASED CARDIOVASCULAR RISK COMPARED TO THOSE WITH NORMAL RENAL FUNCTION. THE TRIGGERS FOR THE IRREVERSIBLE RENAL FUNCTION DETERIORATION ARE MULTIFACTORIAL, AND DIABETES MELLITUS SERVES AS A MAJOR CONTRIBUTOR TO THE DEVELOPMENT OF CKD, NAMELY DIABETIC KIDNEY DISEASE (DKD). RECENTLY, EPIGENETIC DYSREGULATION EMERGED AS A PIVOTAL PLAYER STEERING THE PROGRESSION OF DKD, PARTLY RESULTING FROM HYPERGLYCEMIA-ASSOCIATED METABOLIC DISTURBANCES, RISING OXIDATIVE STRESS, AND/OR UNCONTROLLED INFLAMMATION. IN THIS REVIEW, WE DESCRIBE THE MAJOR EPIGENETIC MOLECULAR MECHANISMS, FOLLOWED BY SUMMARIZING CURRENT UNDERSTANDINGS OF THE EPIGENETIC ALTERATIONS PERTAINING TO DKD. WE HIGHLIGHT THE EPIGENETIC REGULATORY PROCESSES INVOLVED IN SEVERAL CRUCIAL RENAL CELL TYPES: MESANGIAL CELLS, PODOCYTES, TUBULAR EPITHELIA, AND GLOMERULAR ENDOTHELIAL CELLS. FINALLY, WE HIGHLIGHT EPIGENETIC BIOMARKERS AND RELATED THERAPEUTIC CANDIDATES THAT HOLD PROMISING POTENTIAL FOR THE EARLY DETECTION OF DKD AND THE AMELIORATION OF ITS PROGRESSION. 2022 11 4822 22 OCHRATOXIN A: 50 YEARS OF RESEARCH. SINCE OCHRATOXIN A (OTA) WAS DISCOVERED, IT HAS BEEN UBIQUITOUS AS A NATURAL CONTAMINANT OF MOLDY FOOD AND FEED. THE MULTIPLE TOXIC EFFECTS OF OTA ARE A REAL THREAT FOR HUMAN BEINGS AND ANIMAL HEALTH. FOR EXAMPLE, OTA CAN CAUSE PORCINE NEPHROPATHY BUT CAN ALSO DAMAGE POULTRIES. HUMANS EXPOSED TO OTA CAN DEVELOP (NOTABLY BY INHALATION IN THE DEVELOPMENT OF ACUTE RENAL FAILURE WITHIN 24 H) A RANGE OF CHRONIC DISORDERS SUCH AS UPPER UROTHELIAL CARCINOMA. OTA PLAYS THE MAIN ROLE IN THE PATHOGENESIS OF SOME RENAL DISEASES INCLUDING BALKAN ENDEMIC NEPHROPATHY, KIDNEY TUMORS OCCURRING IN CERTAIN ENDEMIC REGIONS OF THE BALKAN PENINSULA, AND CHRONIC INTERSTITIAL NEPHROPATHY OCCURRING IN NORTHERN AFRICAN COUNTRIES AND LIKELY IN OTHER PARTS OF THE WORLD. OTA LEADS TO DNA ADDUCT FORMATION, WHICH IS KNOWN FOR ITS GENOTOXICITY AND CARCINOGENICITY. THE PRESENT ARTICLE DISCUSSES HOW RENAL CARCINOGENICITY AND NEPHROTOXICITY CAUSE BOTH OXIDATIVE STRESS AND DIRECT GENOTOXICITY. CAREFUL ANALYSES OF THE DATA SHOW THAT OTA CARCINOGENIC EFFECTS ARE DUE TO COMBINED DIRECT AND INDIRECT MECHANISMS (E.G., GENOTOXICITY, OXIDATIVE STRESS, EPIGENETIC FACTORS). ALTOGETHER THIS PROVIDES STRONG EVIDENCE THAT OTA CARCINOGENICITY CAN ALSO OCCUR IN HUMANS. 2016 12 2579 24 EPIGENETICS OF KIDNEY DISEASE. DNA METHYLATION AND HISTONE MODIFICATIONS DETERMINE RENAL PROGRAMMING AND THE DEVELOPMENT AND PROGRESSION OF RENAL DISEASE. THE IDENTIFICATION OF THE WAY IN WHICH THE RENAL CELL EPIGENOME IS ALTERED BY ENVIRONMENTAL MODIFIERS DRIVING THE ONSET AND PROGRESSION OF RENAL DISEASES HAS EXTENDED OUR UNDERSTANDING OF THE PATHOPHYSIOLOGY OF KIDNEY DISEASE PROGRESSION. IN THIS REVIEW, WE FOCUS ON CURRENT KNOWLEDGE CONCERNING THE IMPLICATIONS OF EPIGENETIC MODIFICATIONS DURING RENAL DISEASE FROM EARLY DEVELOPMENT TO CHRONIC KIDNEY DISEASE PROGRESSION INCLUDING RENAL FIBROSIS, DIABETIC NEPHROPATHY AND THE TRANSLATIONAL POTENTIAL OF IDENTIFYING NEW BIOMARKERS AND TREATMENTS FOR THE PREVENTION AND THERAPY OF CHRONIC KIDNEY DISEASE AND END-STAGE KIDNEY DISEASE. 2017 13 5370 22 RECENT ADVANCES IN UNDERSTANDING OF CHRONIC KIDNEY DISEASE. CHRONIC KIDNEY DISEASE (CKD) IS DEFINED AS ANY CONDITION THAT CAUSES REDUCED KIDNEY FUNCTION OVER A PERIOD OF TIME. FIBROSIS, TUBULAR ATROPHY AND INTERSTITIAL INFLAMMATION ARE THE HALLMARK OF PATHOLOGICAL FEATURES IN CKD. REGARDLESS OF INITIAL INSULT, CKD HAS SOME COMMON PATHWAYS LEADING CKD TO END-STAGE KIDNEY DISEASE, INCLUDING HYPOXIA IN THE TUBULOINTERSTITIUM AND PROTEINURIA. RECENT ADVANCES IN GENOME EDITING TECHNOLOGIES AND STEM CELL RESEARCH GIVE GREAT INSIGHTS TO UNDERSTAND THE PATHOGENESIS OF CKD, INCLUDING IDENTIFICATIONS OF THE ORIGINS OF RENAL MYOFIBROBLASTS AND TUBULAR EPITHELIAL CELLS UPON INJURY. ENVIRONMENTAL FACTORS SUCH AS HYPOXIA, OXIDATIVE STRESS, AND EPIGENETIC FACTORS IN RELATION TO CKD ARE ALSO DISCUSSED. 2015 14 2285 19 EPIGENETIC REGULATION IN KIDNEY TOXICITY: INSIGHTS FROM CISPLATIN NEPHROTOXICITY. NEPHROTOXICITY, AS A RESULT OF THE EXPOSURE OF KIDNEY TO ENDOGENOUS AND EXOGENOUS TOXINS, IS AN IMPORTANT FACTOR FOR ACUTE KIDNEY INJURY AND THE DEVELOPMENT OF PROGRESSIVE CHRONIC KIDNEY DISEASE. CISPLATIN IS AMONG THE MOST WIDELY STUDIED KIDNEY TOXICANTS. IN THE PAST DECADE, EPIGENETIC REGULATION HAS EMERGED AS A NOTABLE PATHOGENIC MECHANISM IN CISPLATIN NEPHROTOXICITY, INCLUDING DNA METHYLATION, HISTONE MODIFICATION, AND NONCODING RNAS. IN THIS REVIEW, WE USE CISPLATIN NEPHROTOXICITY AS AN EXAMPLE TO HIGHLIGHT THE EPIGENETIC ALTERATION, FUNCTION, AND UNDERLYING MECHANISM IN KIDNEY TOXICITY. THE STUDY OF EPIGENETIC REGULATION IN KIDNEY TOXICITY IS STILL IN ITS INFANCY, AND FURTHER INVESTIGATION WILL BRING NEW INSIGHTS FOR THE DEVELOPMENT OF NOVEL DIAGNOSTIC BIOMARKERS AND THERAPEUTIC INTERVENTIONS. 2019 15 4820 24 OCHRATOXIN A AS A POTENTIAL ETIOLOGIC FACTOR IN ENDEMIC NEPHROPATHY: LESSONS FROM TOXICITY STUDIES IN RATS. VARIOUS REPORTS SUGGEST THAT CHRONIC DIETARY EXPOSURE TO OCHRATOXIN A (OTA), A MYCOTOXIN FREQUENTLY DETECTED IN VARIOUS FOOD ITEMS MAY BE LINKED TO THE PATHOGENESIS OF ENDEMIC NEPHROPATHY, A CHRONIC TUBULOINTERSTITIAL KIDNEY DISEASE WHICH OCCURS IN GEOGRAPHICALLY LIMITED AREAS OF THE BALKAN REGION. OTA IS A POTENT NEPHROTOXIN AND RENAL CARCINOGEN. HOWEVER, THE PATHOLOGICAL LESIONS OBSERVED IN KIDNEYS OF RATS TREATED WITH OTA APPEAR BE RATHER DIFFERENT FROM THE CLINICAL AND PATHOLOGICAL CHARACTERISTICS OF ENDEMIC NEPHROPATHY. MOREOVER, INCREASING EVIDENCE SUGGESTS THAT OTA DOES NOT BIND TO DNA BUT INDUCES TUMORS BY AN EPIGENETIC, THRESHOLDED MECHANISM. THIS IMPLIES THAT THERE IS A DOSE BELOW WHICH NO ADVERSE HEALTH EFFECTS ARE EXPECTED TO OCCUR. BASED ON FOOD CONSUMPTION DATA AND OTA SERUM CONCENTRATIONS, IT APPEARS THAT HUMAN EXPOSURE - EVEN IN AREAS WITH RELATIVELY HIGH DIETARY EXPOSURE TO OTA SUCH AS ENDEMIC VILLAGES - IS SEVERAL ORDERS OF MAGNITUDE BELOW DOSES KNOWN TO CAUSE NEPHROTOXICITY AND TUMOR FORMATION IN LABORATORY ANIMALS. WHILE IT IS UNDOUBTEDLY IMPORTANT TO ENCOURAGE PREVENTION OF FOOD CONTAMINATION BY OTA AND OTHER MYCOTOXINS, THESE OBSERVATIONS SUGGEST THAT OTA IS NOT LIKELY TO BE AN ETIOLOGICAL FACTOR INVOLVED IN BEN AND INDICATE A NEED TO SEARCH FOR NEW CLUES FOR THE ETIOLOGY OF THIS ENDEMIC KIDNEY DISEASE. 2007 16 4513 17 MULTI-OMIC APPROACHES TO ACUTE KIDNEY INJURY AND REPAIR. THE KIDNEY HAS A REMARKABLE REGENERATIVE CAPACITY. IN RESPONSE TO ISCHEMIC OR TOXIC INJURY, PROXIMAL TUBULE CELLS CAN PROLIFERATE TO REBUILD DAMAGED TUBULES AND RESTORE KIDNEY FUNCTION. HOWEVER, SEVERE ACUTE KIDNEY INJURY (AKI) OR RECURRENT AKI EVENTS CAN LEAD TO MALADAPTIVE REPAIR AND DISEASE PROGRESSION FROM AKI TO CHRONIC KIDNEY DISEASE (CKD). THE APPLICATION OF SINGLE CELL TECHNOLOGIES HAS IDENTIFIED INJURED PROXIMAL TUBULE CELL STATES WEEKS AFTER AKI, DISTINGUISHED BY A PRO-INFLAMMATORY SENESCENT MOLECULAR SIGNATURE. EPIGENETIC STUDIES HIGHLIGHTED DYNAMIC CHANGES IN THE CHROMATIN LANDSCAPE OF THE KIDNEY FOLLOWING AKI AND DESCRIBED KEY TRANSCRIPTION FACTORS LINKED TO THE AKI RESPONSE. THE INTEGRATION OF MULTI-OMIC TECHNOLOGIES OPENS NEW POSSIBILITIES TO IMPROVE OUR UNDERSTANDING OF AKI AND THE DRIVING FORCES BEHIND THE AKI-TO-CKD TRANSITION, WITH THE ULTIMATE GOAL OF DESIGNING TAILORED DIAGNOSTIC AND THERAPEUTIC STRATEGIES TO IMPROVE AKI OUTCOMES AND PREVENT KIDNEY DISEASE PROGRESSION. 2021 17 4971 26 PATHOPHYSIOLOGIC MECHANISMS IN DIABETIC KIDNEY DISEASE: A FOCUS ON CURRENT AND FUTURE THERAPEUTIC TARGETS. DIABETIC KIDNEY DISEASE (DKD) IS THE PRIMARY CAUSE OF CHRONIC KIDNEY DISEASE AROUND THE GLOBE AND IS ONE OF THE MAIN COMPLICATIONS IN PATIENTS WITH TYPE 1 AND 2 DIABETES. THE STANDARD TREATMENT FOR DKD IS DRUGS CONTROLLING HYPERGLYCEMIA AND HIGH BLOOD PRESSURE. RENIN ANGIOTENSIN ALDOSTERONE SYSTEM BLOCKADE AND SODIUM GLUCOSE COTRANSPORTER 2 (SGLT2) INHIBITION HAVE YIELDED PROMISING RESULTS IN DKD, BUT MANY DIABETIC PATIENTS ON SUCH TREATMENTS NEVERTHELESS CONTINUE TO DEVELOP DKD, LEADING TO KIDNEY FAILURE AND CARDIOVASCULAR COMORBIDITIES. NEW THERAPEUTIC OPTIONS ARE URGENTLY REQUIRED. WE REVIEW HERE THE PROMISING THERAPEUTIC AVENUES BASED ON INSIGHTS INTO THE MECHANISMS OF DKD THAT HAVE RECENTLY EMERGED, INCLUDING MINERALOCORTICOID RECEPTOR ANTAGONISTS, SGLT2 INHIBITORS, GLUCAGON-LIKE PEPTIDE-1 RECEPTOR AGONIST, ENDOTHELIN RECEPTOR A INHIBITION, ANTI-INFLAMMATORY AGENTS, AUTOPHAGY ACTIVATORS AND EPIGENETIC REMODELLING. THE INVOLVEMENT OF SEVERAL MOLECULAR MECHANISMS IN DKD PATHOGENESIS, TOGETHER WITH THE GENETIC AND EPIGENETIC VARIABILITY OF THIS CONDITION, MAKES IT DIFFICULT TO TARGET THIS HETEROGENEOUS PATIENT POPULATION WITH A SINGLE DRUG. PERSONALIZED MEDICINE, TAKING INTO ACCOUNT THE GENETIC AND MECHANISTIC VARIABILITY, MAY THEREFORE IMPROVE RENAL AND CARDIOVASCULAR PROTECTION IN DIABETIC PATIENTS WITH DKD. 2020 18 6299 29 THE PROXIMAL TUBULE IS THE PRIMARY TARGET OF INJURY AND PROGRESSION OF KIDNEY DISEASE: ROLE OF THE GLOMERULOTUBULAR JUNCTION. THERE IS AN ALARMING GLOBAL INCREASE IN THE INCIDENCE OF END-STAGE KIDNEY DISEASE, FOR WHICH EARLY BIOMARKERS AND EFFECTIVE TREATMENT OPTIONS ARE LACKING. LARGELY BASED ON THE HISTOLOGY OF THE END-STAGE KIDNEY AND ON THE MODEL OF UNILATERAL URETERAL OBSTRUCTION, CURRENT INVESTIGATION IS FOCUSED ON THE PATHOGENESIS OF RENAL INTERSTITIAL FIBROSIS AS A CENTRAL MECHANISM IN THE PROGRESSION OF CHRONIC KIDNEY DISEASE (CKD). IT IS NOW RECOGNIZED THAT CUMULATIVE EPISODES OF ACUTE KIDNEY INJURY (AKI) CAN LEAD TO CKD, AND, CONVERSELY, CKD IS A RISK FACTOR FOR AKI. BASED ON RECENT AND HISTORIC STUDIES, THIS REVIEW SHIFTS ATTENTION FROM THE GLOMERULUS AND INTERSTITIUM TO THE PROXIMAL TUBULE AS THE PRIMARY SENSOR AND EFFECTOR IN THE PROGRESSION OF CKD AS WELL AS AKI. PACKED WITH MITOCHONDRIA AND DEPENDENT ON OXIDATIVE PHOSPHORYLATION, THE PROXIMAL TUBULE IS PARTICULARLY VULNERABLE TO INJURY (OBSTRUCTIVE, ISCHEMIC, HYPOXIC, OXIDATIVE, METABOLIC), RESULTING IN CELL DEATH AND ULTIMATELY IN THE FORMATION OF ATUBULAR GLOMERULI. ANIMAL MODELS OF HUMAN GLOMERULAR AND TUBULAR DISORDERS HAVE PROVIDED EVIDENCE FOR A BROAD REPERTOIRE OF MORPHOLOGICAL AND FUNCTIONAL RESPONSES OF THE PROXIMAL TUBULE, REVEALING PROCESSES OF DEGENERATION AND REPAIR THAT MAY LEAD TO NEW THERAPEUTIC STRATEGIES. MOST PROMISING ARE STUDIES THAT ENCOMPASS THE ENTIRE LIFE CYCLE FROM FETUS TO SENESCENCE, RECOGNIZING EPIGENETIC FACTORS. THE APPLICATION OF TECHNIQUES IN MOLECULAR CHARACTERIZATION OF TUBULE SEGMENTS AND THE DEVELOPMENT OF HUMAN KIDNEY ORGANOIDS MAY PROVIDE NEW INSIGHTS INTO THE MAMMALIAN KIDNEY SUBJECTED TO STRESS OR INJURY, LEADING TO BIOMARKERS OF EARLY CKD AND NEW THERAPIES. 2016 19 2034 23 EPIGENETIC CHANGES IN THE ACUTE KIDNEY INJURY-TO-CHRONIC KIDNEY DISEASE TRANSITION. PREVIOUSLY ACUTE KIDNEY INJURY (AKI) HAD BEEN BELIEVED TO BE A TRANSIENT EVENT, AND RECOVERY FROM AKI HAD BEEN THOUGHT TO LEAD TO NO CONSEQUENCES. HOWEVER, RECENT EPIDEMIOLOGICAL STUDIES HAVE SHOWN THAT EVEN IF THERE IS COMPLETE RECOVERY OF THE KIDNEY FUNCTION, AKI CAN EVENTUALLY RESULT IN CHRONIC KIDNEY DISEASE (CKD) AND EVENTUALLY IN END-STAGE KIDNEY DISEASE IN THE LONG TERM. TRANSITION OF AKI TO CKD IS MEDIATED BY MULTIPLE MECHANISMS, INCLUDING ABERRANT CELL CYCLE ARREST AND HYPOXIA. HYPOXIA OF THE KIDNEY IS INDUCED BY RAREFACTION OF THE PERITUBULAR CAPILLARIES AFTER AKI EPISODES, AND INDUCES INFLAMMATION AND FIBROSIS. IT SHOULD ALSO BE NOTED THAT EPIGENETIC CHANGES ARE CLOSELY RELATED TO HYPOXIA, AND EPIGENETIC CHANGES INDUCED BY HYPOXIA, CALLED "HYPOXIC MEMORY" CAN EXPLAIN THE AKI-TO-CKD TRANSITION IN THE LONG TERM AFTER COMPLETE RECOVERY FROM THE INITIAL AKI EPISODE. TARGETING HYPOXIA AND SUBSEQUENT EPIGENETIC CHANGES ARE PROMISING STRATEGIES TO BLOCK THE TRANSITION FROM AKI TO CKD. 2017 20 1665 30 DOWNREGULATION OF KIDNEY PROTECTIVE FACTORS BY INFLAMMATION: ROLE OF TRANSCRIPTION FACTORS AND EPIGENETIC MECHANISMS. CHRONIC KIDNEY DISEASE (CKD) IS ASSOCIATED TO AN INCREASED RISK OF DEATH, CKD PROGRESSION, AND ACUTE KIDNEY INJURY (AKI) EVEN FROM EARLY STAGES, WHEN GLOMERULAR FILTRATION RATE (GFR) IS PRESERVED. THE LINK BETWEEN EARLY CKD AND THESE RISKS IS UNCLEAR, SINCE THERE IS NO ACCUMULATION OF UREMIC TOXINS. HOWEVER, PATHOLOGICAL ALBUMINURIA AND KIDNEY INFLAMMATION ARE FREQUENT FEATURES OF EARLY CKD, AND THE PRODUCTION OF KIDNEY PROTECTIVE FACTORS MAY BE DECREASED. INDEED, KLOTHO EXPRESSION IS ALREADY DECREASED IN CKD CATEGORY G1 (NORMAL GFR). KLOTHO HAS ANTI-AGING AND NEPHROPROTECTIVE PROPERTIES, AND DECREASED KLOTHO LEVELS MAY CONTRIBUTE TO INCREASE THE RISK OF DEATH, CKD PROGRESSION, AND AKI. IN THIS REVIEW, WE DISCUSS THE DOWNREGULATION BY MEDIATORS OF INFLAMMATION OF MOLECULES WITH SYSTEMIC AND/OR RENAL LOCAL PROTECTIVE FUNCTIONS, EXEMPLIFIED BY KLOTHO AND PEROXISOME PROLIFERATOR-ACTIVATED RECEPTOR GAMMA COACTIVATOR-1ALPHA (PGC-1ALPHA), A TRANSCRIPTION FACTOR THAT PROMOTES MITOCHONDRIAL BIOGENESIS. CYTOKINES SUCH AS TWEAK, TNF-ALPHA, OR TRANSFORMING GROWTH FACTOR -BETA1 PRODUCED LOCALLY DURING KIDNEY INJURY OR RELEASED FROM INFLAMMATORY SITES AT OTHER ORGANS MAY DECREASE KIDNEY EXPRESSION OF KLOTHO AND PGC-1ALPHA OR LEAD TO SUBOPTIMAL RECRUITMENT OF THESE NEPHROPROTECTIVE PROTEINS. TRANSCRIPTION FACTORS (E.G., SMAD3 AND NF-KAPPAB) AND EPIGENETIC MECHANISMS (E.G., HISTONE ACETYLATION OR METHYLATION) CONTRIBUTE TO DOWNREGULATE THE EXPRESSION OF KLOTHO AND/OR PGC-1ALPHA, WHILE HISTONE CROTONYLATION PROMOTES PGC-1ALPHA EXPRESSION. NF-KAPPABIZ FACILITATES THE REPRESSIVE EFFECT OF NF-KAPPAB ON KLOTHO EXPRESSION. A DETAILED UNDERSTANDING OF THESE MEDIATORS MAY CONTRIBUTE TO THE DEVELOPMENT OF NOVEL THERAPEUTIC APPROACHES TO PREVENT CKD PROGRESSION AND ITS NEGATIVE IMPACT ON MORTALITY AND AKI. 2016