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 2 448 24 APABETALONE MEDIATED EPIGENETIC MODULATION IS ASSOCIATED WITH FAVORABLE KIDNEY FUNCTION AND ALKALINE PHOSPHATASE PROFILE IN PATIENTS WITH CHRONIC KIDNEY DISEASE. BACKGROUND/AIMS: THE ASSOCIATION BETWEEN SERUM ALKALINE PHOSPHATASE (ALP) WITH ADVERSE CARDIOVASCULAR OUTCOMES, IN CHRONIC KIDNEY DISEASE (CKD) PATIENTS HAS PREVIOUSLY BEEN REPORTED AND MAY BE A RESULT OF INCREASED VASCULAR CALCIFICATION AND INFLAMMATION. HERE WE REPORT, FOR THE FIRST TIME, THE EFFECTS OF PHARMACOLOGIC EPIGENETIC MODULATION ON LEVELS OF ALP AND KIDNEY FUNCTION VIA A NOVEL ORAL SMALL MOLECULE BET INHIBITOR, APABETALONE, IN CKD PATIENTS. METHODS: A POST-HOC ANALYSIS EVALUATED PATIENTS WITH ESTIMATED GLOMERULAR FILTRATION RATE (EGFR) <60 ML/MIN/1.73M2, WHO PARTICIPATED IN THE APABETALONE PHASE 2 RANDOMIZED CONTROLLED TRIALS (SUSTAIN AND ASSURE). 48 CKD SUBJECTS WITH A HISTORY OF CARDIOVASCULAR DISEASE (CVD) WERE TREATED WITH 100MG TWICE-DAILY OF 24 AND 26 WEEKS OF APABETALONE OR PLACEBO. ALP AND EGFR WERE MEASURED PRIOR TO RANDOMIZATION AND AT FINAL VISITS. RESULTS: PATIENTS WHO RECEIVED APABETALONE (N=35) VERSUS PLACEBO (N=13) OVER 6 MONTHS SHOWED SIGNIFICANTLY (P=0.02) LOWERED SERUM ALP -14.0% (P<0.0001 VERSUS BASELINE) VERSUS -6.3% (P=0.9 VERSUS BASELINE). THE EGFR IN THE APABETALONE GROUP INCREASED BY 3.4% (1.7 ML/MIN/1.73 M2) (P=0.04 VERSUS BASELINE) AND DECREASED BY 5.8% (2.9 ML/MIN/1.73 M2) (P=0.6 VERSUS BASELINE) IN THE PLACEBO GROUP. APABETALONE WAS WELL TOLERATED. CONCLUSION: A POST-HOC ANALYSIS OF CKD SUBJECTS FROM THE SUSTAIN AND ASSURE RANDOMIZED CONTROLLED TRIALS DEMONSTRATED FAVORABLE EFFECTS OF APABETALONE ON ALP AND EGFR, AND GENERATED THE HYPOTHESIS THAT EPIGENETIC MODULATION BY BET INHIBITION MAY POTENTIALLY OFFER A NOVEL THERAPEUTIC STRATEGY TO TREAT CVD AND PROGRESSIVE KIDNEY FUNCTION LOSS IN CKD PATIENTS. THIS IS BEING EXAMINED IN THE PHASE III TRIAL BETONMACE. 2018 3 1625 23 DNAM-BASED SIGNATURES OF ACCELERATED AGING AND MORTALITY IN BLOOD ARE ASSOCIATED WITH LOW RENAL FUNCTION. BACKGROUND: THE DIFFERENCE BETWEEN AN INDIVIDUAL'S CHRONOLOGICAL AND DNA METHYLATION PREDICTED AGE (DNAMAGE), TERMED DNAMAGE ACCELERATION (DNAMAA), CAN CAPTURE LIFE-LONG ENVIRONMENTAL EXPOSURES AND AGE-RELATED PHYSIOLOGICAL CHANGES REFLECTED IN METHYLATION STATUS. SEVERAL STUDIES HAVE LINKED DNAMAA TO MORBIDITY AND MORTALITY, YET ITS RELATIONSHIP WITH KIDNEY FUNCTION HAS NOT BEEN ASSESSED. WE EVALUATED THE ASSOCIATIONS BETWEEN SEVEN DNAM AGING AND LIFESPAN PREDICTORS (AS WELL AS GRIMAGE COMPONENTS) AND FIVE KIDNEY TRAITS (ESTIMATED GLOMERULAR FILTRATION RATE [EGFR], URINE ALBUMIN-TO-CREATININE RATIO [UACR], SERUM URATE, MICROALBUMINURIA AND CHRONIC KIDNEY DISEASE [CKD]) IN UP TO 9688 EUROPEAN, AFRICAN AMERICAN AND HISPANIC/LATINO INDIVIDUALS FROM SEVEN POPULATION-BASED STUDIES. RESULTS: WE IDENTIFIED 23 SIGNIFICANT ASSOCIATIONS IN OUR LARGE TRANS-ETHNIC META-ANALYSIS (P < 1.43E-03 AND CONSISTENT DIRECTION OF EFFECT ACROSS STUDIES). AGE ACCELERATION MEASURED BY THE EXTRINSIC AND PHENOAGE ESTIMATORS, AS WELL AS ZHANG'S 10-CPG EPIGENETIC MORTALITY RISK SCORE (MRS), WERE ASSOCIATED WITH ALL PARAMETERS OF POOR KIDNEY HEALTH (LOWER EGFR, PREVALENT CKD, HIGHER UACR, MICROALBUMINURIA AND HIGHER SERUM URATE). SIX OF THESE ASSOCIATIONS WERE INDEPENDENTLY OBSERVED IN EUROPEAN AND AFRICAN AMERICAN POPULATIONS. MRS IN PARTICULAR WAS CONSISTENTLY ASSOCIATED WITH EGFR (BETA = - 0.12, 95% CI = [- 0.16, - 0.08] CHANGE IN LOG-TRANSFORMED EGFR PER UNIT INCREASE IN MRS, P = 4.39E-08), PREVALENT CKD (ODDS RATIO (OR) = 1.78 [1.47, 2.16], P = 2.71E-09) AND HIGHER SERUM URATE LEVELS (BETA = 0.12 [0.07, 0.16], P = 2.08E-06). THE "FIRST-GENERATION" CLOCKS (HANNUM, HORVATH) AND GRIMAGE SHOWED DIFFERENT PATTERNS OF ASSOCIATION WITH THE KIDNEY TRAITS. THREE OF THE DNAM-ESTIMATED COMPONENTS OF GRIMAGE, NAMELY ADRENOMEDULLIN, PLASMINOGEN-ACTIVATION INHIBITION 1 AND PACK YEARS, WERE POSITIVELY ASSOCIATED WITH HIGHER UACR, SERUM URATE AND MICROALBUMINURIA. CONCLUSION: DNAMAGE ACCELERATION AND DNAM MORTALITY PREDICTORS ESTIMATED IN WHOLE BLOOD WERE ASSOCIATED WITH MULTIPLE KIDNEY TRAITS, INCLUDING EGFR AND CKD, IN THIS MULTI-ETHNIC STUDY. EPIGENETIC BIOMARKERS WHICH REFLECT THE SYSTEMIC EFFECTS OF AGE-RELATED MECHANISMS SUCH AS IMMUNOSENESCENCE, INFLAMMAGING AND OXIDATIVE STRESS MAY HAVE IMPORTANT MECHANISTIC OR PROGNOSTIC ROLES IN KIDNEY DISEASE. OUR STUDY HIGHLIGHTS NEW FINDINGS LINKING KIDNEY DISEASE TO BIOLOGICAL AGING, AND OPPORTUNITIES WARRANTING FUTURE INVESTIGATION INTO DNA METHYLATION BIOMARKERS FOR PROGNOSTIC OR RISK STRATIFICATION IN KIDNEY DISEASE. 2021 4 2005 24 EPIGENETIC ASSOCIATIONS WITH ESTIMATED GLOMERULAR FILTRATION RATE AMONG MEN WITH HUMAN IMMUNODEFICIENCY VIRUS INFECTION. BACKGROUND: PEOPLE LIVING WITH HUMAN IMMUNODEFICIENCY VIRUS (HIV) INFECTION HAVE HIGHER RISK FOR CHRONIC KIDNEY DISEASE (CKD), DEFINED BY A REDUCED ESTIMATED GLOMERULAR FILTRATION RATE (EGFR). PREVIOUS STUDIES HAVE IMPLICATED EPIGENETIC CHANGES RELATED TO CKD; HOWEVER, THE MECHANISM OF HIV-RELATED CKD HAS NOT BEEN THOROUGHLY INVESTIGATED. METHODS: WE CONDUCTED AN EPIGENOME-WIDE ASSOCIATION STUDY OF EGFR AMONG 567 HIV-POSITIVE AND 117 HIV-NEGATIVE MALE PARTICIPANTS IN THE VETERANS AGING COHORT STUDY TO IDENTIFY EPIGENETIC SIGNATURES OF KIDNEY FUNCTION. RESULTS: BY SURVEYING MORE THAN 400 000 CYTOSINE GUANINE DINUCLEOTIDE (CPG) SITES MEASURED FROM PERIPHERAL BLOOD MONONUCLEAR CELLS, WE IDENTIFIED 15 SITES THAT WERE SIGNIFICANTLY ASSOCIATED WITH EGFR (FALSE DISCOVERY RATE Q VALUE < 0.05) AMONG HIV-POSITIVE PARTICIPANTS. THE MOST SIGNIFICANT CPG SITES, LOCATED AT MAD1L1, TSNARE1/BAI1, AND LTV1, WERE ALL NEGATIVELY ASSOCIATED WITH EGFR (CG06329547, P = 5.25 X 10-9; CG23281907, P = 1.37 X 10-8; CG18368637, P = 5.17 X 10-8). WE ALSO REPLICATED PREVIOUSLY REPORTED EGFR-ASSOCIATED CPG SITES INCLUDING CG17944885 (P = 2.5 X 10-5) LOCATED BETWEEN ZNF788 AND ZNF20 ON CHROMOSOME 19 IN THE POOLED POPULATION. CONCLUSIONS: IN THIS STUDY WE UNCOVERED NOVEL EPIGENETIC ASSOCIATIONS WITH KIDNEY FUNCTION AMONG PEOPLE LIVING WITH HIV AND SUGGEST POTENTIAL EPIGENETIC MECHANISMS LINKED WITH HIV-RELATED CKD RISK. 2020 5 3383 20 HNF1B NEPHROPATHY HAS A SLOW-PROGRESSIVE PHENOTYPE IN CHILDHOOD-WITH THE EXCEPTION OF VERY EARLY ONSET CASES: RESULTS OF THE GERMAN MULTICENTER HNF1B CHILDHOOD REGISTRY. BACKGROUND: HNF1B GENE MUTATIONS ARE AN IMPORTANT CAUSE OF BILATERAL (CYSTIC) DYSPLASIA IN CHILDREN, COMPLICATED BY CHRONIC RENAL INSUFFICIENCY. THE CLINICAL VARIABILITY, THE ABSENCE OF GENOTYPE-PHENOTYPE CORRELATIONS, AND LIMITED LONG-TERM DATA RENDER COUNSELING OF AFFECTED FAMILIES DIFFICULT. METHODS: LONGITUDINAL DATA OF 62 CHILDREN PROBANDS WITH GENETICALLY PROVEN HNF1B NEPHROPATHY WAS OBTAINED IN A MULTICENTER APPROACH. GENETIC FAMILY CASCADE SCREENING WAS PERFORMED IN 30/62 CASES. RESULTS: EIGHTY-SEVEN PERCENT OF PATIENTS HAD BILATERAL DYSPLASIA, 74% VISIBLE BILATERAL, AND 16% UNILATERAL RENAL CYSTS AT THE END OF OBSERVATION. CYST DEVELOPMENT WAS NON-PROGRESSIVE IN 72% WITH A MEAN GLOMERULAR FILTRATION RATE (GFR) LOSS OF - 0.33 ML/MIN/1.73M(2) PER YEAR (+/- 8.9). IN PATIENTS WITH AN INCREASE IN CYST NUMBER, THE ANNUAL GFR REDUCTION WAS - 2.8 ML/MIN/1.73M(2) (+/- 13.2), IN THE TOTAL COHORT - 1.0 ML/MIN/1.73M(2) (+/-10.3). A SUBSET OF HNF1B PATIENTS DIFFERS FROM THIS GROUP AND DEVELOPS END STAGE RENAL DISEASE (ESRD) AT VERY EARLY AGES < 2 YEARS. HYPERURICEMIA (37%) WAS A FREQUENT FINDING AT YOUNG AGE (MEDIAN 1 YEAR), WHEREAS HYPOMAGNESEMIA (24%), ELEVATED LIVER ENZYMES (21%), AND HYPERGLYCEMIA (8%) SHOWED AN INCREASED INCIDENCE IN THE TEENAGED CHILD. GENETIC ANALYSIS REVEALED NO GENOTYPE-PHENOTYPE CORRELATIONS BUT A SIGNIFICANT PARENT-OF-ORIGIN EFFECT WITH A PREPONDERANCE OF 81% OF MATERNAL INHERITANCE IN DOMINANT CASES. CONCLUSIONS: IN MOST CHILDREN, HNF1B NEPHROPATHY HAS A NON-PROGRESSIVE COURSE OF CYST DEVELOPMENT AND A SLOW-PROGRESSIVE COURSE OF KIDNEY FUNCTION. A SUBGROUP OF PATIENTS DEVELOPED ESRD AT VERY YOUNG AGE < 2 YEARS REQUIRING SPECIAL MEDICAL ATTENTION. THE PARENT-OF-ORIGIN EFFECT SUGGESTS AN INFLUENCE OF EPIGENETIC MODIFIERS IN HNF1B DISEASE. 2019 6 4825 21 OCULAR FUNDUS ABNORMALITIES IN PATIENTS WITH BALKAN ENDEMIC NEPHROPATHY AND OTHER CHRONIC KIDNEY DISEASES. AIM: THE AIM OF THIS STUDY WAS TO EXAMINE THE OCULAR FUNDUS PATHOLOGY IN PATIENTS WITH BALKAN ENDEMIC NEPHROPATHY (BN) AND CHRONIC KIDNEY DISEASES (CKD). METHODS: THE STUDY INCLUDED 51 PATIENTS WITH BN FROM THE SOUTH MORAVA RIVER REGION IN SERBIA, AND 102 SUBJECTS WITH DIFFERENT STAGES OF CHRONIC RENAL DISEASES, MATCHED ACCORDING TO AGE AND GENDER, OBTAINED FROM A DATABASE USED IN A RECENTLY PUBLISHED STUDY. ALL PATIENTS HAD VISITED OUTPATIENT DEPARTMENT OF THE CLINIC OF NEPHROLOGY, CLINICAL CENTER NIS. ALL PATIENTS UNDERWENT ROUTINE OPHTHALMIC EXAMINATIONS. RESULTS: THERE WERE SIGNIFICANTLY MORE (P < 0.001) PATIENTS WITH AGE-RELATED MACULAR DEGENERATION (AMD) IN THE GROUP WITH BN (31.37 %) THAN IN THOSE WITH CKD (5.88 %). MULTIVARIATE LOGISTIC REGRESSION ANALYSIS CONFIRMED THAT THE SIGNIFICANT FACTORS RELATED TO AMD IN THE GROUP WITH BN WERE ALBUMINURIA (P < 0.05) AND PROTEINURIA (P < 0.05); IN CKD PATIENTS, THE LEVEL OF HDL (P < 0.05), WHILE NEGATIVE CORRELATION WITH THE LEVEL OF TRIGLYCERIDE WAS REGISTERED (P < 0.05). THERE WAS NO ASSOCIATION BETWEEN ESTIMATED GLOMERULAR FILTRATION RATE AND AMD. THE SIGNIFICANT FACTORS RELATED TO RETINOPATHY IN THE GROUP WITH BN ARE AGE (P < 0.05) AND SERUM CREATININE VALUES (P < 0.05), IN PATIENTS WITH CKD INCREASING AGE (P < 0.001) AND DM (P < 0.05). CONCLUSION: OCULAR FUNDUS PATHOLOGY IN PATIENTS WITH BN IS SIMILAR TO THE PATHOLOGY OF OTHER CKD, BUT WITH SIGNIFICANTLY MORE AMD (ABOUT FOUR TIMES), PROBABLY RELATED TO THE GENETIC/EPIGENETIC FACTORS. 2015 7 307 25 ALBUMINURIA DOWNREGULATION OF THE ANTI-AGING FACTOR KLOTHO: THE MISSING LINK POTENTIALLY EXPLAINING THE ASSOCIATION OF PATHOLOGICAL ALBUMINURIA WITH PREMATURE DEATH. TEN PERCENT OF THE ADULT POPULATION HAS CHRONIC KIDNEY DISEASE (CKD), WHICH IS DIAGNOSED WHEN THE GLOMERULAR FILTRATION RATE (GFR) IS BELOW 60 ML/MIN PER 1.73 M(2) OR WHEN ALBUMINURIA IS ABOVE 30 MG/DAY. THE NUMERICAL THRESHOLDS WERE CHOSEN BECAUSE THEY ARE ASSOCIATED WITH AN INCREASED RISK OF CKD PROGRESSION OR PREMATURE DEATH WITHIN A WIDER SCENARIO OF ACCELERATED AGING. INDEED, CKD IS ONE OF THE FASTEST GROWING CAUSES OF DEATH WORLDWIDE. A DECREASED GFR IS ASSOCIATED WITH THE ACCUMULATION OF URAEMIC TOXINS THAT MAY PROMOTE TISSUE AND ORGAN DAMAGE. HOWEVER, CKD MAY BE DIAGNOSED WHEN THE GFR IS COMPLETELY NORMAL, AS LONG AS THERE IS PATHOLOGICAL ALBUMINURIA. A KEY UNANSWERED QUESTION TO STEM THE RISE OF CKD-ASSOCIATED DEATHS IS WHETHER THE ASSOCIATION BETWEEN ISOLATED ALBUMINURIA (WHEN THE GFR IS NORMAL) AND PREMATURE DEATH IS CAUSAL. THE RECENT DEMONSTRATION THAT ALBUMINURIA PER SE DIRECTLY SUPPRESSES THE PRODUCTION OF THE ANTI-AGING FACTOR KLOTHO BY KIDNEY TUBULAR CELLS MAY BE ONE OF THE FIRST STEPS TO ADDRESS THE CAUSALITY OF THE ALBUMINURIA-PREMATURE DEATH-ACCELERATED AGING ASSOCIATION. THIS HYPOTHESIS SHOULD BE TESTED IN INTERVENTIONAL STUDIES THAT SHOULD DRAW FROM TRANSLATIONAL SCIENCE ADVANCES. THUS, THE OBSERVATION THAT ALBUMINURIA DECREASES KLOTHO PRODUCTION THROUGH EPIGENETIC MECHANISMS IMPLIES THAT KLOTHO DOWNREGULATION MAY PERSIST AFTER THE CORRECTION OF ALBUMINURIA, AND INNOVATIVE THERAPEUTIC APPROACHES ARE NEEDED TO RESTORE KLOTHO PRODUCTION. ON THE BASIS OF RECENT LITERATURE, THESE MAY INCLUDE MANIPULATION OF NF-KAPPAB REGULATORS SUCH AS B CELL LYMPHOMA 3 PROTEIN (BCL-3), AND EPIGENETIC REGULATORS SUCH AS HISTONE DEACETYLASES, OR THE REPURPOSING OF DRUGS SUCH AS PENTOXIFYLLINE. 2020 8 1271 26 CYTOSINE METHYLATION PREDICTS RENAL FUNCTION DECLINE IN AMERICAN INDIANS. DIABETIC NEPHROPATHY ACCOUNTS FOR MOST OF THE EXCESS MORTALITY IN INDIVIDUALS WITH DIABETES, BUT THE MOLECULAR MECHANISMS BY WHICH NEPHROPATHY DEVELOPS ARE LARGELY UNKNOWN. HERE WE TESTED CYTOSINE METHYLATION LEVELS AT 397,063 GENOMIC CPG SITES FOR ASSOCIATION WITH DECLINE IN THE ESTIMATED GLOMERULAR FILTRATION RATE (EGFR) OVER A SIX YEAR PERIOD IN 181 DIABETIC PIMA INDIANS. METHYLATION LEVELS AT 77 SITES SHOWED SIGNIFICANT ASSOCIATION WITH EGFR DECLINE AFTER CORRECTION FOR MULTIPLE COMPARISONS. A MODEL INCLUDING METHYLATION LEVEL AT TWO PROBES (CG25799291 AND CG22253401) IMPROVED PREDICTION OF EGFR DECLINE IN ADDITION TO BASELINE EGFR AND THE ALBUMIN TO CREATININE RATIO WITH THE PERCENT OF VARIANCE EXPLAINED SIGNIFICANTLY IMPROVING FROM 23.1% TO 42.2%. CG22253401 WAS ALSO SIGNIFICANTLY ASSOCIATED WITH EGFR DECLINE IN A CASE-CONTROL STUDY DERIVED FROM THE CHRONIC RENAL INSUFFICIENCY COHORT. PROBES AT WHICH METHYLATION SIGNIFICANTLY ASSOCIATED WITH EGFR DECLINE WERE LOCALIZED TO GENE REGULATORY REGIONS AND ENRICHED FOR GENES WITH METABOLIC FUNCTIONS AND APOPTOSIS. THREE OF THE 77 PROBES THAT WERE ASSOCIATED WITH EGFR DECLINE IN BLOOD SAMPLES SHOWED DIRECTIONALLY CONSISTENT AND SIGNIFICANT ASSOCIATION WITH FIBROSIS IN MICRODISSECTED HUMAN KIDNEY TISSUE, AFTER CORRECTION FOR MULTIPLE COMPARISONS. THUS, CYTOSINE METHYLATION LEVELS MAY PROVIDE BIOMARKERS OF DISEASE PROGRESSION IN DIABETIC NEPHROPATHY AND EPIGENETIC VARIATIONS CONTRIBUTE TO THE DEVELOPMENT OF DIABETIC KIDNEY DISEASE. 2018 9 1576 27 DNA METHYLATION PROFILE ASSOCIATED WITH RAPID DECLINE IN KIDNEY FUNCTION: FINDINGS FROM THE CRIC STUDY. BACKGROUND: EPIGENETIC MECHANISMS MAY BE IMPORTANT IN THE PROGRESSION OF CHRONIC KIDNEY DISEASE (CKD). METHODS: WE STUDIED THE GENOME-WIDE DNA METHYLATION PATTERN ASSOCIATED WITH RAPID LOSS OF KIDNEY FUNCTION USING THE INFINIUM HUMANMETHYLATION 450 K BEADCHIP IN 40 CHRONIC RENAL INSUFFICIENCY (CRIC) STUDY PARTICIPANTS (N = 3939) WITH THE HIGHEST AND LOWEST RATES OF DECLINE IN ESTIMATED GLOMERULAR FILTRATION RATE. RESULTS: THE MEAN EGFR SLOPE WAS 2.2 (1.4) AND -5.1 (1.2) ML/MIN/1.73 M(2) IN THE STABLE KIDNEY FUNCTION GROUP AND THE RAPID PROGRESSION GROUP, RESPECTIVELY. CPG ISLANDS IN NPHP4, IQSEC1 AND TCF3 WERE HYPERMETHYLATED TO A LARGER EXTENT IN SUBJECTS WITH STABLE KIDNEY FUNCTION (P-VALUES OF 7.8E-05 TO 9.5E-05). THESE GENES ARE INVOLVED IN PATHWAYS KNOWN TO PROMOTE THE EPITHELIAL TO MESENCHYMAL TRANSITION AND RENAL FIBROSIS. OTHER CKD-RELATED GENES THAT WERE DIFFERENTIALLY METHYLATED ARE NOS3, NFKBIL2, CLU, NFKBIB, TGFB3 AND TGFBI, WHICH ARE INVOLVED IN OXIDATIVE STRESS AND INFLAMMATORY PATHWAYS (P-VALUES OF 4.5E-03 TO 0.046). PATHWAY ANALYSIS USING INGENUITY PATHWAY ANALYSIS SHOWED THAT GENE NETWORKS RELATED TO CELL SIGNALING, CARBOHYDRATE METABOLISM AND HUMAN BEHAVIOR ARE EPIGENETICALLY REGULATED IN CKD. CONCLUSIONS: EPIGENETIC MODIFICATIONS MAY BE IMPORTANT IN DETERMINING THE RATE OF LOSS OF KIDNEY FUNCTION IN PATIENTS WITH ESTABLISHED CKD. 2014 10 3592 23 IMPAIRED VASCULAR FUNCTION CONTRIBUTES TO EXERCISE INTOLERANCE IN CHRONIC KIDNEY DISEASE. BACKGROUND: EXERCISE INTOLERANCE IS AN IMPORTANT FEATURE IN PATIENTS WITH CHRONIC KIDNEY DISEASE (CKD) AND IS PROGNOSTIC FOR BOTH INCREASED MORBIDITY AND MORTALITY. LITTLE IS KNOWN ABOUT THE UNDERLYING MECHANISMS IN PREDIALYSIS CKD. THIS STUDY AIMED TO GAIN MORE INSIGHT INTO THE ROLE OF VASCULAR DYSFUNCTION IN THE EXERCISE INTOLERANCE OF PREDIALYSIS CKD. IN ADDITION, VASCULAR-RELATED MICRORNAS (MIRNAS)-AS EPIGENETIC REGULATORS OF EXERCISE CAPACITY-WERE ANALYSED. METHODS: SIXTY-THREE PATIENTS WITH CKD STAGES 1-5 AND 18 HEALTHY CONTROLS WERE INCLUDED. PEAK OXYGEN CONSUMPTION (VO(2)PEAK) WAS DETERMINED BY CARDIOPULMONARY EXERCISE TESTING, ENDOTHELIAL FUNCTION BY FLOW-MEDIATED DILATION (FMD) AND ARTERIAL STIFFNESS BY CAROTID-FEMORAL PULSE WAVE VELOCITY (PWV). PLASMA MIRNA LEVELS (MIR-21, MIR-126, MIR-146A, MIR-150 AND MIR-210) WERE QUANTIFIED BY QUANTITATIVE RT-PCR. RESULTS: VO(2)PEAK WAS ALREADY IMPAIRED IN MILD CKD (STAGES 1-3A) AND SIGNIFICANTLY CORRELATED WITH ESTIMATED GLOMERULAR FILTRATION RATE (EGFR; R = 0.525, P < 0.001). LIKEWISE, BOTH FMD AND PWV WERE SIGNIFICANTLY CORRELATED WITH EGFR (R = 0.319, P = 0.007 AND R = -0.365, P = 0.001, RESPECTIVELY). IN MULTIPLE REGRESSION ANALYSIS, PWV REMAINED ONE OF THE STRONGEST INDEPENDENT DETERMINANTS OF VO(2)PEAK (BETA = -0.301, P = 0.01). OF THE STUDIED MIRNA, CIRCULATING LEVELS OF MIR-146A AND MIR-150 CORRELATED WITH EGFR, PWV AND VO(2)PEAK, BUT THE ASSOCIATION WITH THE LATTER WAS LOST WHEN CORRECTING FOR PWV. CONCLUSIONS: ARTERIAL STIFFNESS CONTRIBUTES TO THE OBSERVED REDUCED AEROBIC CAPACITY IN PREDIALYSIS CKD, INDEPENDENT OF AGE, HAEMOGLOBIN LEVELS AND ENDOTHELIAL FUNCTION AND REPRESENTS A PROMISING THERAPEUTIC TARGET FOR IMPROVING EXERCISE CAPACITY IN THIS POPULATION. FUTURE WORK IS REQUIRED TO ELUCIDATE WHY HIGHER CIRCULATING LEVELS OF MIR-146A AND MIR-150 ARE ASSOCIATED WITH IMPAIRED RENAL FUNCTION AND INCREASED ARTERIAL STIFFNESS. 2016 11 6080 21 THE EFFECT OF DNA METHYLATION IN THE DEVELOPMENT AND PROGRESSION OF CHRONIC KIDNEY DISEASE IN THE GENERAL POPULATION: AN EPIGENOME-WIDE ASSOCIATION STUDY USING THE KOREAN GENOME AND EPIDEMIOLOGY STUDY DATABASE. BACKGROUND: ALTHOUGH KNOWLEDGE OF THE GENETIC FACTORS INFLUENCING KIDNEY DISEASE IS INCREASING, EPIGENETIC PROFILES, WHICH ARE ASSOCIATED WITH CHRONIC KIDNEY DISEASE (CKD), HAVE NOT BEEN FULLY ELUCIDATED. WE SOUGHT TO IDENTIFY THE DNA METHYLATION STATUS OF CPG SITES ASSOCIATED WITH REDUCED KIDNEY FUNCTION AND EXAMINE WHETHER THE IDENTIFIED CPG SITES ARE ASSOCIATED WITH CKD DEVELOPMENT. METHOD: WE ANALYZED DNA METHYLATION PATTERNS OF 440 PARTICIPANTS IN THE KOREAN GENOME AND EPIDEMIOLOGY STUDY (KOGES) WITH ESTIMATED GLOMERULAR FILTRATION RATES (EGFRS) >/= 60 ML/MIN/1.73 M(2) AT BASELINE. CKD DEVELOPMENT WAS DEFINED AS A DECREASE IN THE EGFR OF <60 AT ANY TIME DURING AN 8-YEAR FOLLOW-UP PERIOD ("CKD PREDICTION" ANALYSIS). IN ADDITION, AMONG THE 440 PARTICIPANTS, 49 PARTICIPANTS WHO UNDERWENT A SECOND METHYLATION PROFILING WERE ASSESSED FOR AN ASSOCIATION BETWEEN A DECLINE IN KIDNEY FUNCTION AND CHANGES IN THE DEGREE OF METHYLATION OF CPG SITES DURING THE 8 YEARS ("KIDNEY FUNCTION SLOPE" ANALYSIS). RESULTS: IN THE CKD PREDICTION ANALYSIS, METHYLATION PROFILES OF A TOTAL OF 403,129 CPG SITES WERE EVALUATED AT BASELINE IN 440 PARTICIPANTS, AND INCREASED AND DECREASED METHYLATION OF 268 AND 189 CPG SITES, RESPECTIVELY, WERE SIGNIFICANTLY CORRELATED WITH THE DEVELOPMENT OF CKD IN MULTIVARIABLE LOGISTIC REGRESSION. DURING KIDNEY FUNCTION SLOPE ANALYSIS USING FOLLOW-UP METHYLATION PROFILES OF 49 PARTICIPANTS, THE PERCENT METHYLATION CHANGES IN 913 CPG SITES SHOWED A LINEAR RELATIONSHIP WITH THE PERCENT CHANGE IN EGFR DURING 8 YEARS. DURING FUNCTIONAL ENRICHMENT ANALYSES FOR SIGNIFICANT CPG SITES FOUND IN THE CKD PREDICTION AND KIDNEY FUNCTION SLOPE ANALYSES, WE FOUND THAT THOSE CPG SITES REPRESENTED MAPK, PI3K/AKT, AND RAP1 PATHWAYS. IN ADDITION, THREE CPG SITES FROM THREE GENES, NPHS2, CHCHD4, AND AHR, WERE FOUND TO BE SIGNIFICANT IN THE CKD PREDICTION ANALYSIS AND RELATED TO A DECLINE IN KIDNEY FUNCTION. CONCLUSION: IT IS SUGGESTED THAT DNA METHYLATION ON SPECIFIC GENES IS ASSOCIATED WITH THE DEVELOPMENT OF CKD AND THE DETERIORATION OF KIDNEY FUNCTION. 2023 12 2621 24 EPIGENOME-WIDE ASSOCIATION STUDIES IDENTIFY DNA METHYLATION ASSOCIATED WITH KIDNEY FUNCTION. CHRONIC KIDNEY DISEASE (CKD) IS DEFINED BY REDUCED ESTIMATED GLOMERULAR FILTRATION RATE (EGFR). PREVIOUS GENETIC STUDIES HAVE IMPLICATED REGULATORY MECHANISMS CONTRIBUTING TO CKD. HERE WE PRESENT EPIGENOME-WIDE ASSOCIATION STUDIES OF EGFR AND CKD USING WHOLE-BLOOD DNA METHYLATION OF 2264 ARIC STUDY AND 2595 FRAMINGHAM HEART STUDY PARTICIPANTS TO IDENTIFY EPIGENETIC SIGNATURES OF KIDNEY FUNCTION. OF 19 CPG SITES SIGNIFICANTLY ASSOCIATED (P < 1E-07) WITH EGFR/CKD AND REPLICATED, FIVE ALSO ASSOCIATE WITH RENAL FIBROSIS IN BIOPSIES FROM CKD PATIENTS AND SHOW CONCORDANT DNA METHYLATION CHANGES IN KIDNEY CORTEX. LEAD CPGS AT PTPN6/PHB2, ANKRD11, AND TNRC18 MAP TO ACTIVE ENHANCERS IN KIDNEY CORTEX. AT PTPN6/PHB2 CG19942083, METHYLATION IN KIDNEY CORTEX ASSOCIATES WITH LOWER RENAL PTPN6 EXPRESSION, HIGHER EGFR, AND LESS RENAL FIBROSIS. THE REGIONS CONTAINING THE 243 EGFR-ASSOCIATED (P < 1E-05) CPGS ARE SIGNIFICANTLY ENRICHED FOR TRANSCRIPTION FACTOR BINDING SITES OF EBF1, EP300, AND CEBPB (P < 5E-6). OUR FINDINGS HIGHLIGHT KIDNEY FUNCTION ASSOCIATED EPIGENETIC VARIATION. 2017 13 3884 37 KIDNEY DISEASE IN DIABETES. PERSONS WITH DIABETES MAKE UP THE FASTEST GROWING GROUP OF KIDNEY DIALYSIS AND TRANSPLANT RECIPIENTS IN THE UNITED STATES. IN 1985, WHEN THE FIRST EDITION OF DIABETES IN AMERICA WAS PUBLISHED, 20,961 PERSONS WITH DIABETES WERE RECEIVING RENAL REPLACEMENT THERAPY, REPRESENTING 29% OF ALL NEW CASES OF END-STAGE RENAL DISEASE (ESRD). BY 2012, 239,837 PERSONS WITH DIABETES WERE ON RENAL REPLACEMENT THERAPY, ACCOUNTING FOR 44% OF ALL NEW ESRD CASES. THE INCREASED COUNT REFLECTS GROWTH IN DIABETES PREVALENCE AND INCREASED ACCESS TO DIALYSIS AND TRANSPLANTATION. THOSE WITH A PRIMARY DIAGNOSIS OF DIABETES HAVE LOWER SURVIVAL RELATIVE TO OTHER CAUSES OF ESRD, PRIMARILY BECAUSE OF THE COEXISTENT MORBIDITY ASSOCIATED WITH DIABETES, PARTICULARLY CARDIOVASCULAR DISEASES (CVD). WHILE SURVIVAL ON DIALYSIS HAS SLOWLY IMPROVED ACROSS MODALITIES SINCE THE 1990S, IT REMAINS REDUCED IN PERSONS WITH DIABETES, HALF OF WHOM DIE WITHIN 3 YEARS OF BEGINNING DIALYSIS IN THE UNITED STATES. SIMILAR TO PERSONS WITH ESRD IN GENERAL, THE LEADING CAUSES OF DEATH AMONG ADULTS WITH DIABETES WHO STARTED DIALYSIS IN 1995-2009 WERE CVD (58% OF THE DEATHS) AND INFECTIONS (13% OF THE DEATHS). KIDNEY TRANSPLANT RECIPIENTS WITH DIABETES HAVE MUCH BETTER SURVIVAL THAN THOSE ON DIALYSIS, INDICATING A SIGNIFICANT IMPACT OF THE TYPE OF RENAL REPLACEMENT THERAPY (TRANSPLANT VERSUS DIALYSIS) ON LONG-TERM SURVIVAL. KIDNEY FAILURE AFFECTS ABOUT 1% OF PERSONS WITH DIABETES IN THE UNITED STATES. A CONSIDERABLY HIGHER PROPORTION, ABOUT 40%, HAVE LESS SEVERE KIDNEY DISEASE. SINCE THE SECOND EDITION OF DIABETES IN AMERICA WAS PUBLISHED IN 1995, A WEALTH OF NEW INFORMATION HAS CONTRIBUTED SUBSTANTIALLY TO THE UNDERSTANDING OF KIDNEY DISEASE ASSOCIATED WITH DIABETES. IN 2002, THE NATIONAL KIDNEY FOUNDATION'S KIDNEY DISEASE OUTCOME QUALITY INITIATIVE PUBLISHED A UNIFORM DEFINITION OF CHRONIC KIDNEY DISEASE (CKD) AND CLASSIFICATION OF ITS STAGES IRRESPECTIVE OF UNDERLYING CAUSE, THUS PROVIDING A COMMON LANGUAGE FOR DEFINING BOTH THE SEVERITY AND PROGNOSIS OF KIDNEY DISEASE. THE DEFINITION AND CLASSIFICATION OF CKD WERE SUBSEQUENTLY UPDATED AND REFINED BY THE KIDNEY DISEASE: IMPROVING GLOBAL OUTCOMES IN 2012. ACCORDINGLY, CKD IS CLASSIFIED BASED ON BOTH ALBUMINURIA AND GLOMERULAR FILTRATION RATE (GFR) CATEGORIES, AND TOGETHER WITH KIDNEY FAILURE, THESE CONDITIONS ARE COLLECTIVELY REFERRED TO AS CKD, REGARDLESS OF ETIOLOGY. IN ADDITION, THE KIDNEY DISEASE: IMPROVING GLOBAL OUTCOMES RECOMMENDS USING EQUATIONS TO ESTIMATE GFR (EGFR), WHICH INCLUDE THE ROUTINELY OBTAINED VARIABLES SERUM CREATININE, AGE, SEX, AND RACE/ETHNICITY. THE USE OF SERUM CYSTATIN C, AN ENDOGENOUS FILTRATION MARKER LESS INFLUENCED THAN SERUM CREATININE BY VARIATIONS IN MUSCLE MASS, DIET, AND TUBULAR SECRETION, HAS EMERGED AS AN ALTERNATIVE OR AN ADJUNCT TO SERUM CREATININE-BASED EQUATIONS, PARTICULARLY IN PERSONS WITH DIABETES, IN WHOM EARLY KIDNEY DISEASE IS OFTEN CHARACTERIZED BY ELEVATED GFR. SINCE THE LATE 1990S, NEW MOLECULAR MECHANISMS HAVE BEEN DEFINED THAT ARE HELPING TO EXPLAIN THE DEVELOPMENT AND PROGRESSION OF DIABETIC KIDNEY DISEASE. GLOMERULAR STRUCTURAL LESIONS WERE FOUND TO EXPLAIN 95% OF THE VARIABILITY IN ALBUMIN EXCRETION AND 78% OF GFR VARIABILITY. THE LATTER PERCENTAGE INCREASED TO 92% BY ADDING INDICES OF GLOMERULAR-TUBULAR JUNCTION ABNORMALITIES AND INTERSTITIAL EXPANSION TO THE REGRESSION MODELS. PODOCYTE INJURY APPEARS TO PLAY AN ESSENTIAL ROLE IN THE PROGRESSION OF DIABETIC NEPHROPATHY. IN PERSONS WITH EITHER TYPE 1 OR TYPE 2 DIABETES, PODOCYTE CHANGES MAY OCCUR EVEN BEFORE THE INCREASE IN ALBUMINURIA, SUGGESTING THAT DIABETES ITSELF MAY INDUCE PODOCYTE ALTERATIONS. MUCH HAS ALSO BEEN WRITTEN ABOUT THE PROGNOSTIC IMPLICATIONS OF CKD. ELEVATED ALBUMINURIA AND LOW GFR ARE ASSOCIATED WITH ESRD, FATAL AND NONFATAL CVD, AND ALL-CAUSE MORTALITY. A META-ANALYSIS OF 1,024,977 PARTICIPANTS (NEARLY 13% WITH DIABETES) FROM 30 GENERAL POPULATION AND HIGH-RISK CARDIOVASCULAR COHORTS AND 13 CKD COHORTS INDICATED THAT WHILE THE ABSOLUTE RISKS FOR ALL-CAUSE AND CVD MORTALITY ARE HIGHER IN THE PRESENCE OF DIABETES, THE RELATIVE RISKS OF ESRD OR DEATH BY EGFR AND ALBUMINURIA ARE SIMILAR WITH OR WITHOUT DIABETES. THESE FINDINGS UNDERSCORE THE IMPORTANCE OF KIDNEY DISEASE PER SE AS A PREDICTOR OF IMPORTANT CLINICAL OUTCOMES, REGARDLESS OF THE UNDERLYING CAUSE OF KIDNEY DISEASE. NEW BIOMARKERS OF DIABETIC KIDNEY DISEASE APPEAR TO HAVE ADDITIONAL PROGNOSTIC INFORMATION BEYOND THAT PROVIDED BY ALBUMINURIA. THESE MARKERS INCLUDE KIDNEY INJURY MOLECULE 1, LIVER FATTY ACID-BINDING PROTEIN, N-ACETYL-BETA-D-GLUCOSAMINIDASE, NEUTROPHIL GELATINASE-ASSOCIATED LIPOCALIN, BETA-TRACE PROTEIN, BETA(2)-MICROGLOBULIN, AND TUMOR NECROSIS FACTOR RECEPTORS 1 AND 2. MANY CONCEPTS ABOUT RISK FACTORS FOR CKD ILLUSTRATED IN THIS CHAPTER HAVE NOT CHANGED SINCE 1995, AND WHERE THEY HAVE, THOSE CHANGES ARE DISCUSSED. IN PARTICULAR, MAJOR ADVANCES HAVE BEEN MADE IN ELUCIDATING THE GENETIC AND EPIGENETIC COMPLEXITY OF CKD, WHICH CONTRIBUTED TO DEFINING CELLULAR METABOLIC MEMORY AND THE UNDERSTANDING OF THE LONGLASTING EFFECTS OF STRICT GLYCEMIC CONTROL OBSERVED IN PERSONS WITH TYPE 1 DIABETES OR TYPE 2 DIABETES. IMPROVEMENTS IN THE MANAGEMENT OF PERSONS WITH DIABETES AND CKD HAVE EXTENDED THE TIME COURSE FROM ONSET OF SEVERE ALBUMINURIA TO ESRD AND REDUCED THE OCCURRENCE OF CVD. IN TYPE 1 DIABETES, THE COMBINED DIABETES CONTROL AND COMPLICATIONS TRIAL (DCCT) AND ITS LONG-TERM FOLLOW-UP, THE EPIDEMIOLOGY OF DIABETES INTERVENTIONS AND COMPLICATIONS (EDIC) OBSERVATIONAL STUDY, INDICATED THAT INTENSIVE EARLY METABOLIC CONTROL REDUCED THE RISK OF IMPAIRED GFR BY 50% AND OF CVD OUTCOMES BY 42%, WITH A SPECIFIC 57% DECREASE IN MYOCARDIAL INFARCTION, STROKE, OR DEATH FROM CVD, EFFECTS THAT WERE PARTLY MEDIATED BY THE REDUCED INCIDENCE OF DIABETIC KIDNEY DISEASE. AMONG PERSONS WITH TYPE 2 DIABETES, A META-ANALYSIS OF RANDOMIZED CONTROLLED TRIALS INDICATED THAT MORE INTENSIVE GLYCEMIC CONTROL (GLYCOSYLATED HEMOGLOBIN [A1C] <7%) WAS ASSOCIATED WITH A SIGNIFICANT 10% REDUCTION IN ALBUMINURIA BUT HAD NO EFFECTS ON MORTALITY, KIDNEY FAILURE, OR OTHER VASCULAR OUTCOMES. THE ACTION TO CONTROL CARDIOVASCULAR RISK IN DIABETES (ACCORD) TRIAL, TARGETING AN A1C LEVEL <6.0% IN THE INTENSIVE INTERVENTION ARM, REPORTED AN INCREASED RISK OF CVD DEATH FOR INTENSIVE VERSUS CONVENTIONAL GLYCEMIC CONTROL, ALTHOUGH IT REMAINS UNCLEAR WHETHER THIS EFFECT WAS RELATED TO MORE HYPOGLYCEMIC EPISODES, THE USE OF ADDITIONAL HYPOGLYCEMIC MEDICINES, OR TO THE TARGET GLYCEMIC LEVEL ITSELF. LIKEWISE, THE MODEST GAINS IN INTERMEDIATE OUTCOMES IN THE INTENSIVE TREATMENT ARMS OF THE ACTION IN DIABETES AND VASCULAR DISEASE: PRETERAX AND DIAMICRON MODIFIED RELEASE CONTROLLED EVALUATION (ADVANCE) AND THE VETERANS AFFAIRS DIABETES (VADT) TRIAL WERE COUNTERBALANCED BY A TWOFOLD TO THREEFOLD HIGHER RISK OF SEVERE HYPOGLYCEMIA. TOGETHER, THESE TRIALS INDICATE THAT GLYCEMIC CONTROL IS EXTREMELY USEFUL UP TO A POINT, BUT MORE AGGRESSIVE GLYCEMIC CONTROL MAY BE HARMFUL. SIMILARLY, FOR BLOOD PRESSURE CONTROL, 2014-2015 RECOMMENDATIONS BY THE GUIDELINE-WRITING GROUPS ENDORSE LESS INTENSIVE AND MORE INDIVIDUALIZED BLOOD PRESSURE TARGETS FOR DIABETES AND CKD THAN IN THE PAST. PERSONS WITH DIABETES AND CKD REQUIRE MULTIDISCIPLINARY MANAGEMENT INVOLVING A COMBINATION OF TREATMENTS AND BEHAVIORAL ADJUSTMENTS TO DELAY PROGRESSION OF CKD AND TO PREVENT THE ASSOCIATED COMPLICATIONS. THE STENO-2 STUDY, A LANDMARK PROSPECTIVE, RANDOMIZED TRIAL IN DENMARK, DEMONSTRATED THAT COMPARED WITH CONVENTIONAL TREATMENT, INTENSIVE MULTIFACTORIAL INTERVENTION LED TO 46% LOWER DEATH RATE, 56% LESS SEVERE ALBUMINURIA, 43% LOWER INCIDENCE OF DIABETIC RETINOPATHY, AND 47% LOWER INCIDENCE OF AUTONOMIC NEUROPATHY DURING THE 13.3-YEAR STUDY PERIOD. 2018 14 2148 26 EPIGENETIC MARKERS OF RENAL FUNCTION IN AFRICAN AMERICANS. CHRONIC KIDNEY DISEASE (CKD) IS AN INCREASING CONCERN IN THE UNITED STATES DUE TO ITS RAPIDLY RISING PREVALENCE, PARTICULARLY AMONG AFRICAN AMERICANS. EPIGENETIC DNA METHYLATION MARKERS ARE BECOMING IMPORTANT BIOMARKERS OF CHRONIC DISEASES SUCH AS CKD. TO BETTER UNDERSTAND HOW THESE METHYLATION MARKERS PLAY A ROLE IN KIDNEY FUNCTION, WE MEASURED 26,428 DNA METHYLATION SITES IN 972 AFRICAN AMERICANS FROM THE GENETIC EPIDEMIOLOGY NETWORK OF ARTERIOPATHY (GENOA) STUDY. WE THEN EVALUATED (1) WHETHER EPIGENETIC MARKERS ARE ASSOCIATED WITH ESTIMATED GLOMERULAR FILTRATION RATE (EGFR), (2) WHETHER THE SIGNIFICANTLY ASSOCIATED MARKERS ARE ALSO ASSOCIATED WITH TRADITIONAL RISK FACTORS AND/OR NOVEL BIOMARKERS FOR EGFR, AND (3) HOW MUCH ADDITIONAL VARIATION IN EGFR IS EXPLAINED BY EPIGENETIC MARKERS BEYOND ESTABLISHED RISK FACTORS AND BIOMARKERS. THE MAJORITY OF METHYLATION MARKERS MOST SIGNIFICANTLY ASSOCIATED WITH EGFR (24 OUT OF THE TOP 30) APPEARED TO FUNCTION, AT LEAST IN PART, THROUGH PATHWAYS RELATED TO AGING, INFLAMMATION, OR CHOLESTEROL. HOWEVER, SIX EPIGENETIC MARKERS WERE STILL ABLE TO SIGNIFICANTLY PREDICT EGFR AFTER ADJUSTMENT FOR OTHER RISK FACTORS. THIS WORK SHOWS THAT EPIGENETIC MARKERS MAY OFFER VALUABLE NEW INSIGHT INTO THE COMPLEX PATHOPHYSIOLOGY OF CKD IN AFRICAN AMERICANS. 2013 15 5186 21 PREMATURITY IN MICE LEADS TO REDUCTION IN NEPHRON NUMBER, HYPERTENSION, AND PROTEINURIA. THE NEPHRON NUMBER AT BIRTH IS A QUANTITATIVE TRAIT THAT CORRELATES INVERSELY WITH THE RISK OF HYPERTENSION AND CHRONIC KIDNEY DISEASE LATER IN LIFE. DURING KIDNEY DEVELOPMENT, THE NEPHRON NUMBER IS CONTROLLED BY MULTIPLE FACTORS INCLUDING GENETIC, EPIGENETIC, AND ENVIRONMENTAL MODIFIERS. PREMATURE BIRTH, WHICH REPRESENTS MORE THAN 12% OF ANNUAL LIVE BIRTHS IN THE UNITED STATES, HAS BEEN LINKED TO LOW NEPHRON NUMBER AND THE DEVELOPMENT OF HYPERTENSION LATER IN LIFE. IN THIS REPORT, WE DESCRIBE THE DEVELOPMENT OF A MOUSE MODEL OF PREMATURITY-INDUCED REDUCTION OF NEPHRON NUMBER. PREMATURE MICE, DELIVERED 1 AND 2 DAYS EARLY, HAVE 17.4 +/- 2.3% (N = 6) AND 23.6 +/- 2% (N = 10) FEWER NEPHRONS, RESPECTIVELY, WHEN COMPARED WITH FULL-TERM ANIMALS (12,252 +/- 571 NEPHRONS/KIDNEY, N = 10). AFTER 5 WEEKS OF AGE, THE MICE DELIVERED 2 DAYS PREMATURE SHOW LOWER REAL-TIME GLOMERULAR FILTRATION RATE (GFR, 283 +/- 13 VS 389 +/- 26 MUL/MIN). THE PREMATURE MICE ALSO DEVELOP HYPERTENSION (MEAN ARTERIAL PRESSURE [MAP], 134 +/- 18 VS 120 +/- 14 MM HG) AND ALBUMINURIA (286 +/- 83 VS 176 +/- 59 MUG ALBUMIN/MG CREATININE). THIS MOUSE MODEL PROVIDES A PROOF OF CONCEPT THAT PREMATURITY LEADS TO REDUCED NEPHRON NUMBER AND HYPERTENSION, AND THIS MODEL WILL BE USEFUL IN STUDYING THE PATHOPHYSIOLOGY OF PREMATURITY-INDUCED NEPHRON NUMBER REDUCTIONS AND HYPERTENSION. 2012 16 5846 24 STUDY PROTOCOL: RATIONALE AND DESIGN OF THE COMMUNITY-BASED PROSPECTIVE COHORT STUDY OF KIDNEY FUNCTION AND DIABETES IN RURAL NEW MEXICO, THE COMPASS STUDY. BACKGROUND: RURAL AREAS IN THE STATE OF NEW MEXICO HAVE BEEN THE "GROUND-ZERO" FOR THE EPIDEMIC OF DIABETIC CHRONIC KIDNEY DISEASE (CKD) IN THE UNITED STATES. HOWEVER, THERE IS LIMITED RESEARCH ABOUT RISK FACTORS OF DIABETIC CKD IN THIS AREA AND SCARCE DATA REGARDING THE PERFORMANCE OF EMERGING MARKERS OF RENAL FILTRATION AND EPIGENETIC BIOMARKERS OF RENAL FUNCTION AND DIABETES IN THIS AREA WITH ITS UNIQUE ETHNIC/RACIAL POPULATION. WE DESIGNED THE COMPASS STUDY AS A COMMUNITY-BASED PROGRAM IN RURAL NEW MEXICO AIMING TO SCREEN FOR CKD AND TO DISCOVER CKD-RELATED TRANSLATIONAL BIOMARKERS. METHODS/DESIGN: THE STUDY INVOLVES A PROSPECTIVE, LONGITUDINAL COHORT DESIGN INVOLVING INDIVIDUALS LIVING IN RURAL NEW MEXICO. PARTICIPANTS UNDERGO A SCREENING FOR KIDNEY DISEASE USING MARKERS OF ABNORMAL RENAL FILTRATION (IMPAIRED GLOMERULAR FILTRATION RATE) OR DAMAGE (ALBUMINURIA). THOSE FOUND TO HAVE CKD ON THE BASIS OF THESE TESTS OR THOSE AT RISK FOR CKD ARE ENROLLED IN A PROSPECTIVE LONGITUDINAL COHORT. WE MEASURE MARKERS OF RENAL FUNCTION, INSULIN RESISTANCE AND EPIGENETICS (MICRORNAS) ON PATIENTS. INDIVIDUALS ARE INVITED TO PARTICIPATE IN INTERVIEWS AND FOCUS GROUPS IN ORDER TO CHARACTERIZE THEIR ATTITUDES TOWARDS RESEARCH AND BARRIERS OR FACILITATORS TO PARTICIPATION IN FUTURE RESEARCH STUDIES ABOUT KIDNEY DISEASE. DISCUSSION: THIS STUDY WILL PROVIDE IMPORTANT DATA ABOUT THE LOCAL EPIDEMIOLOGY OF KIDNEY DISEASE IN A HIGH-RISK RURAL SETTING AND THE UTILITY OF EMERGING RENAL FILTRATION MARKERS (BETA 2 MICROGLOBULIN AND CYSTATIN C), WHILE GENERATING DATA AND METHODS FOR THE ANALYSES OF MICRORNA BIOMARKERS. THE QUALITATIVE RESEARCH SUBPROJECT WILL IDENTIFY FACTORS ASSOCIATED WITH INCREASED WILLINGNESS TO PARTICIPATE IN FUTURE TRANSLATIONAL RESEARCH PROJECTS. WITH ITS GEOGRAPHICAL FOCUS, THIS STUDY WILL ADDRESS A CRITICAL DISPARITY IN KIDNEY DISEASE RESEARCH, WHILE GENERATING NOVEL EPIGENETIC DATA THAT ARE RELEVANT FOR FUTURE STUDIES IN THE GENERAL POPULATION. 2018 17 933 27 CHRONIC KIDNEY DISEASE. THE DEFINITION AND CLASSIFICATION OF CHRONIC KIDNEY DISEASE (CKD) HAVE EVOLVED OVER TIME, BUT CURRENT INTERNATIONAL GUIDELINES DEFINE THIS CONDITION AS DECREASED KIDNEY FUNCTION SHOWN BY GLOMERULAR FILTRATION RATE (GFR) OF LESS THAN 60 ML/MIN PER 1.73 M(2), OR MARKERS OF KIDNEY DAMAGE, OR BOTH, OF AT LEAST 3 MONTHS DURATION, REGARDLESS OF THE UNDERLYING CAUSE. DIABETES AND HYPERTENSION ARE THE MAIN CAUSES OF CKD IN ALL HIGH-INCOME AND MIDDLE-INCOME COUNTRIES, AND ALSO IN MANY LOW-INCOME COUNTRIES. INCIDENCE, PREVALENCE, AND PROGRESSION OF CKD ALSO VARY WITHIN COUNTRIES BY ETHNICITY AND SOCIAL DETERMINANTS OF HEALTH, POSSIBLY THROUGH EPIGENETIC INFLUENCE. MANY PEOPLE ARE ASYMPTOMATIC OR HAVE NON-SPECIFIC SYMPTOMS SUCH AS LETHARGY, ITCH, OR LOSS OF APPETITE. DIAGNOSIS IS COMMONLY MADE AFTER CHANCE FINDINGS FROM SCREENING TESTS (URINARY DIPSTICK OR BLOOD TESTS), OR WHEN SYMPTOMS BECOME SEVERE. THE BEST AVAILABLE INDICATOR OF OVERALL KIDNEY FUNCTION IS GFR, WHICH IS MEASURED EITHER VIA EXOGENOUS MARKERS (EG, DTPA, IOHEXOL), OR ESTIMATED USING EQUATIONS. PRESENCE OF PROTEINURIA IS ASSOCIATED WITH INCREASED RISK OF PROGRESSION OF CKD AND DEATH. KIDNEY BIOPSY SAMPLES CAN SHOW DEFINITIVE EVIDENCE OF CKD, THROUGH COMMON CHANGES SUCH AS GLOMERULAR SCLEROSIS, TUBULAR ATROPHY, AND INTERSTITIAL FIBROSIS. COMPLICATIONS INCLUDE ANAEMIA DUE TO REDUCED PRODUCTION OF ERYTHROPOIETIN BY THE KIDNEY; REDUCED RED BLOOD CELL SURVIVAL AND IRON DEFICIENCY; AND MINERAL BONE DISEASE CAUSED BY DISTURBED VITAMIN D, CALCIUM, AND PHOSPHATE METABOLISM. PEOPLE WITH CKD ARE FIVE TO TEN TIMES MORE LIKELY TO DIE PREMATURELY THAN THEY ARE TO PROGRESS TO END STAGE KIDNEY DISEASE. THIS INCREASED RISK OF DEATH RISES EXPONENTIALLY AS KIDNEY FUNCTION WORSENS AND IS LARGELY ATTRIBUTABLE TO DEATH FROM CARDIOVASCULAR DISEASE, ALTHOUGH CANCER INCIDENCE AND MORTALITY ARE ALSO INCREASED. HEALTH-RELATED QUALITY OF LIFE IS SUBSTANTIALLY LOWER FOR PEOPLE WITH CKD THAN FOR THE GENERAL POPULATION, AND FALLS AS GFR DECLINES. INTERVENTIONS TARGETING SPECIFIC SYMPTOMS, OR AIMED AT SUPPORTING EDUCATIONAL OR LIFESTYLE CONSIDERATIONS, MAKE A POSITIVE DIFFERENCE TO PEOPLE LIVING WITH CKD. INEQUITY IN ACCESS TO SERVICES FOR THIS DISEASE DISPROPORTIONALLY AFFECTS DISADVANTAGED POPULATIONS, AND HEALTH SERVICE PROVISION TO INCENTIVISE EARLY INTERVENTION OVER PROVISION OF CARE ONLY FOR ADVANCED CKD IS STILL EVOLVING IN MANY COUNTRIES. 2017 18 2629 23 EPIGENOME-WIDE ASSOCIATION STUDY OF DIABETIC CHRONIC KIDNEY DISEASE PROGRESSION IN THE KOREAN POPULATION: THE KNOW-CKD STUDY. SINCE THE ETIOLOGY OF DIABETIC CHRONIC KIDNEY DISEASE (CKD) IS MULTIFACTORIAL, STUDIES ON DNA METHYLATION FOR KIDNEY FUNCTION DETERIORATION HAVE RARELY BEEN PERFORMED DESPITE THE NEED FOR AN EPIGENETIC APPROACH. THEREFORE, THIS STUDY AIMED TO IDENTIFY EPIGENETIC MARKERS ASSOCIATED WITH CKD PROGRESSION BASED ON THE DECLINE IN THE ESTIMATED GLOMERULAR FILTRATION RATE IN DIABETIC CKD IN KOREA. AN EPIGENOME-WIDE ASSOCIATION STUDY WAS PERFORMED USING WHOLE BLOOD SAMPLES FROM 180 CKD RECRUITED FROM THE KNOW-CKD COHORT. PYROSEQUENCING WAS ALSO PERFORMED ON 133 CKD PARTICIPANTS AS AN EXTERNAL REPLICATION ANALYSIS. FUNCTIONAL ANALYSES, INCLUDING THE ANALYSIS OF DISEASE-GENE NETWORKS, REACTOME PATHWAYS, AND PROTEIN-PROTEIN INTERACTION NETWORKS, WERE CONDUCTED TO IDENTIFY THE BIOLOGICAL MECHANISMS OF CPG SITES. A PHENOME-WIDE ASSOCIATION STUDY WAS PERFORMED TO DETERMINE THE ASSOCIATIONS BETWEEN CPG SITES AND OTHER PHENOTYPES. TWO EPIGENETIC MARKERS, CG10297223 ON AGTR1 AND CG02990553 ON KRT28 INDICATED A POTENTIAL ASSOCIATION WITH DIABETIC CKD PROGRESSION. BASED ON THE FUNCTIONAL ANALYSES, OTHER PHENOTYPES (BLOOD PRESSURE AND CARDIAC ARRHYTHMIA FOR AGTR1) AND BIOLOGICAL PATHWAYS (KERATINIZATION AND CORNIFIED ENVELOPE FOR KRT28) RELATED TO CKD WERE ALSO IDENTIFIED. THIS STUDY SUGGESTS A POTENTIAL ASSOCIATION BETWEEN THE CG10297223 AND CG02990553 AND THE PROGRESSION OF DIABETIC CKD IN KOREANS. NEVERTHELESS, FURTHER VALIDATION IS NEEDED THROUGH ADDITIONAL STUDIES. 2023 19 3451 22 HYPERMETHYLATIONS OF RASAL1 AND KLOTHO IS ASSOCIATED WITH RENAL DYSFUNCTION IN A CHINESE POPULATION ENVIRONMENTALLY EXPOSED TO CADMIUM. EXPOSURE TO CADMIUM (CD) CAN AFFECT BOTH DNA METHYLATION AND RENAL FUNCTION, BUT THERE ARE FEW EXAMPLES OF THE ASSOCIATION BETWEEN EPIGENETIC MARKERS AND CD-INDUCED KIDNEY DAMAGE. IT HAS BEEN SUGGESTED THAT HYPERMETHYLATION OF THE GENES RASAL1 AND KLOTHO IS ASSOCIATED WITH RENAL FIBROGENESIS. TO INVESTIGATE WHETHER HYPERMETHYLATION OF RASAL1 AND KLOTHO IN PERIPHERAL BLOOD DNA CAN BE ASSOCIATED WITH CD EXPOSURE AND/OR CD-INDUCED RENAL DYSFUNCTION, THE DEGREES OF METHYLATION OF RASAL1 AND KLOTHO IN PERIPHERAL BLOOD DNA FROM 81 RESIDENTS IN CD-POLLUTED AND NON-POLLUTED AREAS WERE MEASURED USING BISULFATE-PCR-PYROSEQUENCING. CHANGES IN BLOOD CADMIUM (BCD), URINARY CADMIUM (UCD), AND KIDNEY PARAMETERS WERE MEASURED, AND THE GLOMERULAR FILTRATION RATE (EGFR) WAS ESTIMATED. THE LEVELS OF BCD AND UCD CORRELATED POSITIVELY WITH THE LEVELS OF DNA METHYLATION IN RASAL1 AND IN KLOTHO. THE MORE HEAVILY EXPOSED RESIDENTS (BCD, 4.23-13.22MUG/L; UCD, 8.65-32.90MUG/G CREATININE) EXHIBITED OBVIOUS RENAL DYSFUNCTION. NOTABLY, WHEN CD CONCENTRATION IN BLOOD AND URINE WAS ADJUSTED, THE INCREASED METHYLATION LEVEL IN RASAL1 WAS INVERSELY CORRELATED WITH EGFR (P<0.01) BUT THE RELATIONSHIP BETWEEN HYPERMETHYLATION OF KLOTHO AND EGFR WAS NOT STATISTICALLY SIGNIFICANT. THE METHYLATION OF RASAL1 INCREASED ALONG WITH THE INCREASED ABNORMAL PREVALENCE OF EGFR. OUR FINDINGS SUGGEST THAT CD EXPOSURE CAN INDUCE THE HYPERMETHYLATION OF RASAL1 AND KLOTHO. HYPERMETHYLATION OF RASAL1 MAY BE AN INDICATOR OF THE PROGRESS FOR CHRONIC KIDNEY DISEASE. 2013 20 3095 27 GENOMIC APPROACHES IN THE SEARCH FOR MOLECULAR BIOMARKERS IN CHRONIC KIDNEY DISEASE. BACKGROUND: CHRONIC KIDNEY DISEASE (CKD) IS RECOGNISED AS A GLOBAL PUBLIC HEALTH PROBLEM, MORE PREVALENT IN OLDER PERSONS AND ASSOCIATED WITH MULTIPLE CO-MORBIDITIES. DIABETES MELLITUS AND HYPERTENSION ARE COMMON AETIOLOGIES FOR CKD, BUT IGA GLOMERULONEPHRITIS, MEMBRANOUS GLOMERULONEPHRITIS, LUPUS NEPHRITIS AND AUTOSOMAL DOMINANT POLYCYSTIC KIDNEY DISEASE ARE ALSO COMMON CAUSES OF CKD. MAIN BODY: CONVENTIONAL BIOMARKERS FOR CKD INVOLVING THE USE OF ESTIMATED GLOMERULAR FILTRATION RATE (EGFR) DERIVED FROM FOUR VARIABLES (SERUM CREATININE, AGE, GENDER AND ETHNICITY) ARE RECOMMENDED BY CLINICAL GUIDELINES FOR THE EVALUATION, CLASSIFICATION, AND STRATIFICATION OF CKD. HOWEVER, THESE CLINICAL BIOMARKERS PRESENT SOME LIMITATIONS, ESPECIALLY FOR EARLY STAGES OF CKD, ELDERLY INDIVIDUALS, EXTREME BODY MASS INDEX VALUES (SERUM CREATININE), OR ARE INFLUENCED BY INFLAMMATION, STEROID TREATMENT AND THYROID DYSFUNCTION (SERUM CYSTATIN C). THERE IS THEREFORE A NEED TO IDENTIFY ADDITIONAL NON-INVASIVE BIOMARKERS THAT ARE USEFUL IN CLINICAL PRACTICE TO HELP IMPROVE CKD DIAGNOSIS, INFORM PROGNOSIS AND GUIDE THERAPEUTIC MANAGEMENT. CONCLUSION: CKD IS A MULTIFACTORIAL DISEASE WITH ASSOCIATED GENETIC AND ENVIRONMENTAL RISK FACTORS. HENCE, MANY STUDIES HAVE EMPLOYED GENETIC, EPIGENETIC AND TRANSCRIPTOMIC APPROACHES TO IDENTIFY BIOMARKERS FOR KIDNEY DISEASE. IN THIS REVIEW, WE HAVE SUMMARISED THE MOST IMPORTANT STUDIES IN HUMANS INVESTIGATING GENOMIC BIOMARKERS FOR CKD IN THE LAST DECADE. SEVERAL GENES, INCLUDING UMOD, SHROOM3 AND ELMO1 HAVE BEEN STRONGLY ASSOCIATED WITH RENAL DISEASES, AND SOME OF THEIR TRAITS, SUCH AS EGFR AND SERUM CREATININE. THE ROLE OF EPIGENETIC AND TRANSCRIPTOMIC BIOMARKERS IN CKD AND RELATED DISEASES IS STILL UNCLEAR. THE COMBINATION OF MULTIPLE BIOMARKERS INTO CLASSIFIERS, INCLUDING GENOMIC, AND/OR EPIGENOMIC, MAY GIVE A MORE COMPLETE PICTURE OF KIDNEY DISEASES. 2018