Genetic variants of interferon-response factor 5 are associated with the incidence of chronic kidney disease: the D.E.S.I.R. study.

Inflammation has been associated with renal diseases. The Interferon Regulatory Factor (IRF)-5 is a key transcription factor in the pro-inflammatory polarization of M1-like macrophages. GWAS have reported that the IRF5 locus is associated with autoimmune diseases and with the estimated glomerular filtration rate (eGFR). We study whether allelic variations in IRF5 are associated with the incidence of chronic kidney disease (CKD) in a general population. We genotyped eleven IRF5 SNPs in the French D.E.S.I.R. cohort from the general population (n = 4820). Associations of SNPs with baseline renal parameters were assessed. Data were analyzed for three endpoints during a 9-year follow-up, incidence of:at least stage 3 CKD, the KDIGO criterion "certain drop in eGFR", and incidence of micro/macro albuminuria. In the cross-sectional analysis, rs10954213 and rs10954214 were associated with eGFR and rs1874328 with urinary albumin/creatinine ratio (ACR). Rs3807306, rs11761199, rs78658945, rs1874328, rs10954213 and rs11770589 were associated with the incidence of stage 3 CKD in multi-adjusted models. Rs4731532, rs3807306, and rs11761199 were associated with the incidence of CKD defined by the KDIGO. Rs4731532, rs3807306, rs11761199 and rs79288514 were associated with the incidence of micro/macro albuminuria. Our results support the hypothesis of the importance of IRF5 mediated macrophage polarization in the etiology of CKD.

Leukocyte telomere length, allelic variations in related genes and risk of coronary heart disease in people with long-standing type 1 diabetes.

BACKGROUND: Type 1 diabetes is associated with accelerated vascular aging and advanced atherosclerosis resulting in increased rates of cardiovascular disease and premature death. We evaluated associations between Leukocyte telomere length (LTL), allelic variations (SNPs) in LTL-related genes and the incidence of coronary heart disease (CHD) in adults with long-standing type 1 diabetes. METHODS: We assessed associations of LTL, measured at baseline by RT-PCR, and of SNPs in 11 LTL-related genes with the risk of coronary heart disease (CHD: myocardial infarction or coronary revascularization) and all-cause death during follow-up in two multicenter French-Belgian prospective cohorts of people with long-standing type 1 diabetes. RESULTS: In logistic and Cox analyses, the lowest tertile of LTL distribution (short telomeres) at baseline was associated with the prevalence of myocardial infarction at baseline and with increased risk of CHD (Hazard ratio 3.14 (1.39-7.70), p = 0.005, for shorter vs longer tertile of LTL) and all-cause death (Hazard ratio 1.63 (95% CI 1.04-2.55), p = 0.03, for shorter vs combined intermediate and longer tertiles of LTL) during follow-up. Allelic variations in six genes related to telomere biology (TERC, NAF1, TERT, TNKS, MEN1 and BICD1) were also associated with the incidence of CHD during follow-up. The associations were independent of sex, age, duration of diabetes, and a range of relevant confounding factors at baseline. CONCLUSIONS: Our results suggest that short LTL is an independent risk factor for CHD in people with type 1 diabetes.

Plasma total adiponectin and changes in renal function in a cohort from the community: the prospective Data from an Epidemiological Study on the Insulin Resistance Syndrome study.

BACKGROUND: High adiponectin levels are associated with diabetic nephropathy. Nevertheless, it is not known whether plasma adiponectin is associated with renal function decline in the general population. We evaluated whether adiponectin concentrations were associated with changes in renal function in a community cohort, the Data from an Epidemiological Study on the Insulin Resistance Syndrome (DESIR) study. METHODS: Plasma adiponectin concentrations were measured in a random sample of 3284 people from the DESIR study, a 9-year prospective cohort from the general population. Data were analysed for three endpoints during follow-up: incidence of Stage 3 chronic kidney disease (CKD); the Kidney Disease: Improving Global Outcomes (KDIGO) criterion 'certain drop in eGFR' and rapid kidney function decline [estimated glomerular filtration rate (eGFR) slope steeper than -3 mL/min/1.73 m2/year]. RESULTS: After exclusion of participants with an eGFR <60 mL/min/1.73 m2 at baseline and those with type 2 diabetes or impaired fasting glycaemia at any time during follow-up (remaining n = 2174), there was a 113% higher risk for a rapid decline in kidney function in participants with adiponectin above the third tertile (T3) versus below the first tertile (T1) (Ptrend = 0.004) and a 53% higher risk for kidney function decline as defined by the KDIGO criterion (Ptrend = 0.04). In a cross-sectional analysis, adiponectin was positively associated with urinary albumin:creatinine ratio at baseline (P = 0.009). CONCLUSIONS: In a healthy cohort from the general population, higher levels of plasma adiponectin were associated with decreased renal function at baseline and at follow-up. This result is similar to what is observed in people with diabetic nephropathy, in contrast with animal models of nephropathy.

Prognostic value of plasma MR-proADM vs NT-proBNP for heart failure in people with type 2 diabetes: the SURDIAGENE prospective study.

AIMS/HYPOTHESIS: N-terminal pro-B-type natriuretic peptide (NT-proBNP) is the gold standard prognostic biomarker for diagnosis and occurrence of heart failure. Here, we compared its prognostic value for the occurrence of congestive heart failure with that of plasma mid-region pro-adrenomedullin (MR-proADM), a surrogate for adrenomedullin, a vasoactive peptide with vasodilator and natriuretic properties, in people with type 2 diabetes. METHODS: Plasma MR-proADM concentration was measured in baseline samples of a hospital-based cohort of consecutively recruited participants with type 2 diabetes. Our primary endpoint was heart failure requiring hospitalisation. RESULTS: We included 1438 participants (age 65 ± 11 years; 604 women and 834 men). Hospitalisation for heart failure occurred during follow-up (median 64 months) in 206 participants; the incidence rate of heart failure was 2.5 (95% CI 2.2, 2.9) per 100 person-years. Plasma concentrations of MR-proADM and NT-proBNP were significantly associated with heart failure in a Cox multivariable analysis model when adjusted for age, diabetes duration, history of coronary heart disease, proteinuria and baseline eGFR (adjHR [95%CI] 1.83 [1.51, 2.21] and 2.20 [1.86, 2.61], respectively, per 1 SD log10 increment, both p < 0.001). MR-proADM contributed significant supplementary information to the prognosis of heart failure when we considered the clinical risk factors (integrated discrimination improvement [IDI, mean ± SEM] 0.021 ± 0.007, p = 0.001) (Table 3). Inclusion of NT-proBNP in the multivariable model including MR-proADM contributed significant complementary information on prediction of heart failure (IDI [mean ± SEM] 0.028 ± 0.008, p < 0.001). By contrast, MR-proADM did not contribute supplementary information on prediction of heart failure in a model including NT-proBNP (IDI [mean ± SEM] 0.003 ± 0.003, p = 0.27), with similar results for heart failure with reduced ejection fraction and preserved ejection fraction. CONCLUSIONS/INTERPRETATION: MR-proADM is a prognostic biomarker for heart failure in people with type 2 diabetes but gives no significant complementary information on prediction of heart failure compared with NT-proBNP.

Plasma copeptin, kidney disease, and risk for cardiovascular morbidity and mortality in two cohorts of type 2 diabetes.

BACKGROUND: Cardiovascular disease and kidney damage are tightly associated in people with type 2 diabetes. Experimental evidence supports a causal role for vasopressin (or antidiuretic hormone) in the development of diabetic kidney disease (DKD). Plasma copeptin, the COOH-terminal portion of pre-provasopressin and a surrogate marker of vasopressin, was shown to be positively associated with the development and progression of DKD. Here we assessed the association of plasma copeptin with the risk of cardiovascular events during follow-up in two prospective cohorts of type 2 diabetic patients, and we examined if this association could be mediated by deleterious effects of vasopressin on the kidney. METHODS: We studied 3098 and 1407 type 2 diabetic patients from the French cohorts DIABHYCAR and SURDIAGENE, respectively. We considered the incidence during follow-up (median: 5 years) of a combined end point composed of myocardial infarction, coronary revascularization, hospitalization for congestive heart failure, or cardiovascular death. Copeptin concentration was measured in baseline plasma samples by an immunoluminometric assay. RESULTS: The cumulative incidence of cardiovascular events during follow-up by sex-specific tertiles of baseline plasma copeptin was 15.6% (T1), 18.7% (T2) and 21.7% (T3) in DIABHYCAR (p = 0.002), and 27.7% (T1), 34.1% (T2) and 47.6% (T3) in SURDIAGENE (p < 0.0001). Cox proportional hazards survival regression analyses confirmed the association of copeptin with cardiovascular events in both cohorts: hazard ratio with 95% confidence interval for T3 vs. T1 was 1.29 (1.04-1.59), p = 0.02 (DIABHYCAR), and 1.58 (1.23-2.04), p = 0.0004 (SURDIAGENE), adjusted for sex, age, BMI, duration of diabetes, systolic blood pressure, arterial hypertension, HbA1c, total cholesterol, HDL-cholesterol, triglycerides, estimated glomerular filtration rate (eGFR), urinary albumin concentration (UAC), active tobacco smoking, and previous history of myocardial infarction at baseline. No interaction was observed between plasma copeptin and eGFR (p = 0.40) or UAC (p = 0.61) categories on the risk of cardiovascular events in analyses of pooled cohorts. CONCLUSIONS: Plasma copeptin was positively associated with major cardiovascular events in people with type 2 diabetes. This association cannot be solely accounted for by the association of copeptin with kidney-related traits.

Non-severe hypoglycaemia is associated with weight gain in patients with type 1 diabetes: Results from the Diabetes Control and Complication Trial.

It is unclear whether the frequent non-severe episodes of hypoglycaemia observed during intensive glucose control in individuals with type 1 diabetes (T1D) are associated with subsequent weight gain. We analysed the association between non-severe hypoglycaemia and weight gain in 1441 Diabetes Control and Complication Trial (DCCT) participants. Non-severe hypoglycaemia was assessed by hypo-score (ie, number of blood glucose values <70 mg/dL divided by the total number of measurements during the DCCT quarterly visits). Significant associations were observed between the hypo-score and annual and total weight gain. The annual weight gain by hypo-score tertiles was 0.8 ± 1.2 (T1), 1.3 ± 1.5 (T2) and 1.4 ± 1.3 kg/y (T3), P < .001 for T2 and T3 vs T1, and for T3 vs T2. The odds ratio for a weight gain of 1.8 kg/y was 2.14 (95% CI, 1.56-2.93) for T2, and 2.53 (95%CI, 1.85-3.45) for T3 vs T1. These differences in weight gain and in risk of weight gain remained significant after adjustment for sex, age, duration of diabetes, HbA1c at baseline and treatment arms. In conclusion, our analysis shows a significant association between non-severe hypoglycaemia and weight gain in individuals with T1D from the DCCT.

Plasma proprotein-convertase-subtilisin/kexin type 9 (PCSK9) and cardiovascular events in type 2 diabetes.

AIM: To investigate whether plasma concentrations of proprotein-convertase-subtilisin/kexin type 9 (PCSK9) were associated with cardiovascular (CV) events in two cohorts of patients with type 2 diabetes mellitus. METHODS: We considered patients from the DIABHYCAR (n = 3137) and the SURDIAGENE (n = 1468) studies. Baseline plasma PCSK9 concentration was measured using an immunofluorescence assay. In post hoc, but preplanned, analyses we assessed the relationship between PCSK9 and the following endpoints: (1) a combined endpoint of major CV events: CV death, non-fatal myocardial infarction (MI), stroke and heart failure-related hospital admission; (2) a composite of all CV events: MI, stroke, heart failure-related hospital admission, coronary/peripheral angioplasty or bypass, CV death; (3) MI; (4) stroke/transient ischaemic attack (TIA); and (5) CV death. RESULTS: In the DIABHYCAR study, plasma PCSK9 tertiles were associated with the incidence of MI, all CV events and stroke/TIA (P for trend <.05). In adjusted Cox analysis, plasma PCSK9 was associated, independently of classic risk factors, with the incidence of major CV events (hazard ratio [HR] for 1-unit increase of log[PCSK9] 1.28 [95% confidence interval {CI} 1.06-1.55]), the incidence of MI (HR 1.66 [95% CI 1.05-2.63]), and the incidence of all CV events (HR 1.22 [95% CI 1.04-1.44]), but not with CV death. Plasma PCSK9 was not associated with the incidence of CV disease in the participants of the SURDIAGENE study with high CV risk treated with statins and insulin. CONCLUSIONS: We found that PCSK9 was inconsistently associated with CV events in populations with type 2 diabetes. The association may depend on the level of CV risk and the background treatment.

T-cadherin gene variants are associated with nephropathy in subjects with type 1 diabetes.

BACKGROUND: High plasma adiponectin levels are associated with diabetic nephropathy (DN). T-cadherin gene (CDH13) variants have been shown to be associated with adiponectin levels. We investigated associations between allelic variations of CDH13 and DN in subjects with type 1 diabetes. METHODS: Two CDH13 polymorphisms were analysed in 1297 Caucasian subjects with type 1 diabetes from the 'Survival Genetic Nephropathy' (SURGENE) (n = 340, 10-year follow-up), 'Genesis France-Belgium' (GENESIS) (n = 501, 5-year follow-up for n = 462) and 'Génétique de la Néphropathie Diabétique' (GENEDIAB) (n = 456, 9-year follow-up for n = 283) cohorts. Adiponectin levels were measured in plasma samples from GENESIS and GENEDIAB cohorts. RESULTS: Pooled analysis of GENEDIAB and GENESIS studies showed that baseline plasma adiponectin levels were higher in subjects with established/advanced DN at inclusion (P < 0.0001) and in subjects who developed end-stage renal disease (ESRD) at follow-up (P < 0.0001). The minor allele of rs3865188 was associated with lower adiponectin levels (P = 0.006). rs11646213 [odds ratio (OR) 1.47; 95% confidence interval (CI) 1.18-1.85; P = 0.0009] and rs3865188 (OR 0.71; 95% CI 0.57-0.90; P = 0.004) were associated with baseline prevalence of established/advanced DN. These polymorphisms were also associated with the risk of ESRD (0.006 < P < 0.03). The association between rs11646213 (but not rs3865188) and renal function remained significant after adjustment for plasma adiponectin. In SURGENE, rs11646213 [hazard ratio (HR) 1.69; 95% CI 1.01-2.71; P = 0.04] and rs3865188 (HR 0.74; 95% CI 0.55-0.99; P = 0.04) were associated with risk of renal events (defined as progression to more severe DN stages). CONCLUSIONS: Plasma adiponectin levels are associated with the prevalence of DN and the incidence of ESRD in patients with type 1 diabetes. CDH13 polymorphisms are also associated with the prevalence and incidence of DN, and with the incidence of ESRD in these patients. The association between CDH13 and DN may be due to pleiotropic effects, both dependent and independent of plasma adiponectin levels.

Death, end-stage renal disease and renal function decline in patients with diabetic nephropathy in French cohorts of type 1 and type 2 diabetes.

AIMS/HYPOTHESIS: Microvascular complications are a common feature of diabetes but additional research is needed regarding diabetic nephropathy endpoints in type 1 and type 2 diabetes. METHODS: We compared 277 type 1 diabetes patients with 942 type 2 diabetes patients, with clinical proteinuria and no endstage renal disease (ESRD) at baseline, prospectively followed for death, ESRD and decline in estimated glomerular filtration rate (eGFR, all available measures). RESULTS: The incidence rate of death was 67.0 (95% CI 59.2, 74.8) vs. 24.6 (95% CI, 19.0, 30.2) per 1,000 patient-years, in type 2 diabetes and type 1 diabetes, respectively. Unadjusted risk for death was greater for type 2 diabetes patients (HR 3.423; 95% CI, 2.501, 4.683; p<0.0001), but the difference did not persist after adjustment for age (HRage-adj 0.859; 95% CI 0.581, 1.269; p=0.445). The incidence rate of ESRD was 18.4 (95% CI 14.2, 22.5) vs. 47.1 (95%CI 38.4, 55.9) per 1,000 patient-years, in type 2 diabetes and type 1 diabetes, respectively. Unadjusted risk for ESRD was lower in type 2 diabetes (HR 0.399; 95% CI 0.287, 0.554; p<0.0001), but the difference did not persist after adjustment for sex, age and baseline serum creatinine (HRadj 0.989; 95% CI 0.597, 1.639; p=0.965). In a mixed linear model, eGFR decline was not significantly different in type 2 vs. type 1 diabetes (difference in slope −0.19 [0.28] ml min(−1) 1.73 m(−2) year(−1); p=0.512). CONCLUSIONS/INTERPRETATION: In diabetic nephropathy, once baseline risk factors were taken into account the risk for death, ESRD and renal function decline did not significantly differ between type 1 diabetes and type 2 diabetes.

Contribution of the low-frequency, loss-of-function p.R270H mutation in FFAR4 (GPR120) to increased fasting plasma glucose levels.

BACKGROUND: We previously reported that the low-frequency, loss-of-function variant p.R270H in FFAR4 encoding the lipid sensor GPR120 was associated with obesity. Gpr120-deficient mice develop obesity and both impaired fasting glucose and glucose intolerance under a high-fat diet. We aimed to assess the contribution of p.R270H to type 2 diabetes (T2D) risk and the variation of glucose-related traits. METHODS: We genotyped p.R270H in 8996 non-diabetic individuals (among whom 4523 had an oral glucose tolerance test (OGTT)) and in a T2D case-control study including 4725 cases and 4339 controls. The regression models were adjusted for age, sex and body mass index (BMI). RESULTS: We found a significant association between p.R270H and increased fasting glucose levels (ß=0.092±0.05 mmol/L; p=4.13×10(-4)). Furthermore, p.R270H nominally contributed to decreased homeostasis model of pancreatic ß-cell function (HOMA-B; ß=-0.090±0.06; p=6.01×10(-3)). Despite a high statistical power, we did not find any significant association between p.R270H and T2D risk or the variation of fasting insulin levels, the homeostasis model of insulin resistance or OGTT-derived indices. CONCLUSIONS: These results suggest that the low-frequency p.R270H variant which inhibits GPR120 activity might influence fasting glucose levels in a normal physiological range. This study does not exclude that other coding mutations in FFAR4 with stronger functional effect than p.R270H may be associated with T2D.

GUESS-ing polygenic associations with multiple phenotypes using a GPU-based evolutionary stochastic search algorithm.

Genome-wide association studies (GWAS) yielded significant advances in defining the genetic architecture of complex traits and disease. Still, a major hurdle of GWAS is narrowing down multiple genetic associations to a few causal variants for functional studies. This becomes critical in multi-phenotype GWAS where detection and interpretability of complex SNP(s)-trait(s) associations are complicated by complex Linkage Disequilibrium patterns between SNPs and correlation between traits. Here we propose a computationally efficient algorithm (GUESS) to explore complex genetic-association models and maximize genetic variant detection. We integrated our algorithm with a new Bayesian strategy for multi-phenotype analysis to identify the specific contribution of each SNP to different trait combinations and study genetic regulation of lipid metabolism in the Gutenberg Health Study (GHS). Despite the relatively small size of GHS (n  =  3,175), when compared with the largest published meta-GWAS (n > 100,000), GUESS recovered most of the major associations and was better at refining multi-trait associations than alternative methods. Amongst the new findings provided by GUESS, we revealed a strong association of SORT1 with TG-APOB and LIPC with TG-HDL phenotypic groups, which were overlooked in the larger meta-GWAS and not revealed by competing approaches, associations that we replicated in two independent cohorts. Moreover, we demonstrated the increased power of GUESS over alternative multi-phenotype approaches, both Bayesian and non-Bayesian, in a simulation study that mimics real-case scenarios. We showed that our parallel implementation based on Graphics Processing Units outperforms alternative multi-phenotype methods. Beyond multivariate modelling of multi-phenotypes, our Bayesian model employs a flexible hierarchical prior structure for genetic effects that adapts to any correlation structure of the predictors and increases the power to identify associated variants. This provides a powerful tool for the analysis of diverse genomic features, for instance including gene expression and exome sequencing data, where complex dependencies are present in the predictor space.

The loss-of-function PCSK9 p.R46L genetic variant does not alter glucose homeostasis.

AIMS/HYPOTHESIS: Proprotein convertase subtilisin/kexin type 9 (PCSK9) is a critical regulator of cholesterol homeostasis. PCSK9 inhibitors are being actively developed to lower LDL-cholesterol levels. However, there are conflicting data regarding the consequences of Pcsk9 deficiency on glucose homeostasis in mouse models. Here, we analysed in humans the association between the PCSK9 p.R46L loss-of-function (LOF) variant and (1) glucose homeostasis variables; (2) type 2 diabetes status; and (3) the risk of 9 year incident type 2 diabetes in a prospective study. METHODS: PCSK9 p.R46L was genotyped in 4630 French participants from the Data from an Epidemiological Study on the Insulin Resistance Syndrome (DESIR) prospective study and in 1342 French participants with type 2 diabetes. The association between p.R46L and metabolic traits or type 2 diabetes risk was assessed through linear or logistic regression models adjusted for age, sex and BMI. The association between p.R46L and incident type 2 diabetes was assessed using a Cox regression model adjusted for sex, age and BMI at baseline. RESULTS: Significant associations (p < 10(-6)) were found between p.R46L and lower total cholesterol (-0.394 mmol/l), LDL-cholesterol (-0.393 mmol/l) and apolipoprotein B concentrations (-0.099 g/l). However, no significant association was observed between p.R46L and markers of glucose homeostasis (including fasting glucose, fasting insulin, HbA1c, HOMA-B, HOMA-IR) or type 2 diabetes risk. Furthermore, no significant association between p.R46L variant and risk of incident type 2 diabetes was observed in DESIR. CONCLUSIONS/INTERPRETATION: The PCSK9 p.R46L LOF variant was not associated with impaired glucose homeostasis in humans. These data are reassuring regarding the safety of PCSK9 inhibitors.

Plasma extracellular superoxide dismutase concentration, allelic variations in the SOD3 gene and risk of myocardial infarction and all-cause mortality in people with type 1 and type 2 diabetes.

BACKGROUND: Oxidative stress is involved in development of diabetes complications. Extracellular superoxide dismutase (EC-SOD, SOD3) is a major extracellular antioxidant enzyme and is highly expressed in arterial walls. Advanced oxidation protein products (AOPP) and 8-iso-prostaglandin (isoprostane) are markers of oxidative stress. We investigated association of SOD3 gene variants, plasma concentrations of EC-SOD, AOPP and isoprostane with myocardial infarction and mortality in diabetic patients. METHODS: We studied three cohorts designed to evaluate the vascular complications of diabetes: the GENEDIAB study (469 participants with type 1 diabetes at baseline; follow-up data for 259 participants), the GENESIS study (603 participants with type 1 diabetes at baseline; follow-up data for 525 participants) and the DIABHYCAR study (3137 participants with type 2 diabetes at baseline and follow-up). Duration of follow-up was 9, 5, and 5 years, respectively. Main outcome measures were incidence of myocardial infarction, and cardiovascular and total mortality during follow-up. Six single nucleotide polymorphisms in the SOD3 locus were genotyped in the three cohorts. Plasma concentrations of EC-SOD, AOPP, and isoprostane were measured in baseline samples of GENEDIAB participants. RESULTS: In GENEDIAB/GENESIS pooled cohorts, the minor T-allele of rs2284659 variant was inversely associated with the prevalence at baseline (Odds Ratio 0.48, 95% CI 0.29-0.78, p = 0.004) and the incidence during follow-up of myocardial infarction (Hazard Ratio 0.58, 95% CI 0.40-0.83, p = 0.003) and with cardiovascular (HR 0.33, 95% CI 0.08-0.74, p = 0.004) and all-cause mortality (HR 0.44, 95% CI 0.21-0.73, p = 0.0006). The protective allele was associated with higher plasma EC-SOD and lower plasma AOPP concentrations in GENEDIAB. It was also inversely associated with incidence of myocardial infarction (HR 0.75, 95% CI 0.59-0.94, p = 0.01) and all-cause mortality (HR 0.87, 95% CI 0.79-0.97, p = 0.008) in DIABHYCAR. CONCLUSIONS: The T-allele of rs2284659 in the promoter of SOD3 was associated with a more favorable plasma redox status and with better cardiovascular outcomes in diabetic patients. Our results suggest that EC-SOD plays an important role in the mechanisms of vascular protection against diabetes-related oxidative stress.

Plasma Copeptin and Decline in Renal Function in a Cohort from the Community: The Prospective D.E.S.I.R. Study.

BACKGROUND/AIMS: In recent days, chronic kidney disease (CKD) is becoming an increasing public health problem. Identification of factors contributing to its progression is crucial for designing preventive interventions. Previous studies suggested that chronically high vasopressin is deleterious to the renal function. We evaluated plasma copeptin, a surrogate of vasopressin, as a predictor for renal function decline in a community cohort. METHODS: Plasma copeptin was measured at baseline in 1,234 participants from the D.E.S.I.R. study, a prospective cohort from the French general population. All participants were followed for 9 years. Progression towards CKD during follow-up was defined as an estimated glomerular filtration rate (eGFR) below 60 ml/min/1.73 m2 on at least one follow-up visit. We have also considered the criterion 'Certain Drop in eGFR' proposed by the Kidney Disease Improving Global Outcomes (KDIGO) group. RESULTS: Progression towards CKD was observed in 86 (7.0%) participants. Factors like age, female gender, plasma copeptin and use of angiotensin converting enzyme inhibitor or angiotensin 2 receptor blocker at baseline were positively associated, and eGFR inversely associated with CKD progression during follow-up. The hazard ratio per unit of log10-transformed plasma copeptin was 1.65 (95% CI 1.06-2.54) and p=0.02. Copeptin was similarly associated with CKD and this was observed when we considered the KDIGO criterion: OR 3.03 (95% CI 1.21-7.57), p=0.02. CONCLUSION: The plasma copeptin level was independently and positively associated with progression towards CKD in a community-based cohort. Our results add to the available evidence for a deleterious effect of high vasopressin on renal health not only in selected groups of patients with CKD but also in the general population.

Catalase activity, allelic variations in the catalase gene and risk of kidney complications in patients with type 1 diabetes.

AIMS/HYPOTHESIS: Oxidative stress is involved in the pathogenesis of diabetic nephropathy. The antioxidant enzyme catalase plays a key role in redox regulation in the kidney. We investigated associations of catalase gene (CAT) polymorphisms and plasma catalase activity with diabetic nephropathy in type 1 diabetic patients. METHODS: We genotyped nine single nucleotide polymorphisms (SNPs) in the CAT region in participants from the Survival Genetic Nephropathy (SURGENE) (340 French participants, 10 year follow-up) and the Génétique de la Néphropathie Diabétique (GENEDIAB) (444 Belgian and French participants, 8 year follow-up) study cohorts. Replication was performed in a Brazilian cross-sectional cohort (n = 451). Baseline plasma catalase activity was measured in SURGENE (n = 120) and GENEDIAB (n = 391) participants. RESULTS: The A allele of rs7947841 was associated with the prevalence of incipient (OR 2.79, 95% CI 1.21, 6.24, p = 0.01) and established or advanced nephropathy (OR 5.72, 95% CI 1.62, 22.03, p = 0.007), and with the incidence of renal events, which were defined as new cases of microalbuminuria or progression to a more severe stage of nephropathy during follow-up (HR 1.82, 95% CI 1.13, 2.81, p = 0.01) in SURGENE participants. The same risk allele was associated with incipient nephropathy (OR 3.13, 95% CI 1.42, 7.24, p = 0.004) and with the incidence of end-stage renal disease (ESRD) (HR 2.11, 95% CI 1.23, 3.60, p = 0.008) in GENEDIAB participants. In both cohorts, the risk allele was associated with lower catalase activity. Associations with incipient and established or advanced nephropathy were confirmed in the replication cohort. CONCLUSIONS/INTERPRETATION: CAT variants were associated with the prevalence and incidence of diabetic nephropathy and ESRD in type 1 diabetic patients. Our results confirm the protective role of catalase against oxidative stress in the kidney.

High plasma concentrations of acyl-coenzyme A binding protein (ACBP) predispose to cardiovascular disease: Evidence for a phylogenetically conserved proaging function of ACBP.

Autophagy defects accelerate aging, while stimulation of autophagy decelerates aging. Acyl-coenzyme A binding protein (ACBP), which is encoded by a diazepam-binding inhibitor (DBI), acts as an extracellular feedback regulator of autophagy. As shown here, knockout of the gene coding for the yeast orthologue of ACBP/DBI (ACB1) improves chronological aging, and this effect is reversed by knockout of essential autophagy genes (ATG5, ATG7) but less so by knockout of an essential mitophagy gene (ATG32). In humans, ACBP/DBI levels independently correlate with body mass index (BMI) as well as with chronological age. In still-healthy individuals, we find that high ACBP/DBI levels correlate with future cardiovascular events (such as heart surgery, myocardial infarction, and stroke), an association that is independent of BMI and chronological age, suggesting that ACBP/DBI is indeed a biomarker of "biological" aging. Concurringly, ACBP/DBI plasma concentrations correlate with established cardiovascular risk factors (fasting glucose levels, systolic blood pressure, total free cholesterol, triglycerides), but are inversely correlated with atheroprotective high-density lipoprotein (HDL). In mice, neutralization of ACBP/DBI through a monoclonal antibody attenuates anthracycline-induced cardiotoxicity, which is a model of accelerated heart aging. In conclusion, plasma elevation of ACBP/DBI constitutes a novel biomarker of chronological aging and facets of biological aging with a prognostic value in cardiovascular disease.

Allelic variations in superoxide dismutase-1 (SOD1) gene and renal and cardiovascular morbidity and mortality in type 2 diabetic subjects.

BACKGROUND: Oxidative stress is involved in the pathophysiology of renal and cardiovascular complications of diabetes. Superoxide dismutase (SOD) enzymes play a major role in detoxification of reactive oxygen species and protection against oxidative stress. Associations of SOD1 gene variants with diabetic nephropathy were reported in patients with type 1 diabetes. We investigated associations of allelic variations in SOD1 gene with nephropathy and cardiovascular complications in patients with type 2 diabetes. METHODS: Seven SNPs in SOD1 region were analyzed in 3744 type 2 European Caucasian diabetic patients from the DIABHYCAR (a 6-year prospective study) and DIABHYCAR_GENE cohorts. Odds ratios or hazard ratios for prevalence and incidence of diabetic nephropathy and cardiovascular events were estimated. RESULTS: We observed an association of rs1041740 with the prevalence of microalbuminuria at baseline (OR 1.51, 95% CI 1.10-2.10, p=0.01). No association with the incidence of renal events (doubling of the serum creatinine levels or the requirement of hemodialysis or renal transplantation) or cardiovascular events (myocardial infarction or stroke) was observed during follow-up. However, three variants were associated with increased risk of death from cardiovascular causes (sudden death, fatal myocardial infarction or stroke) during the follow-up: rs9974610 (HR 0.64, 95% CI 0.46-0.88, p=0.005), rs10432782 (HR 1.71, 95% CI 1.16-2.48, p=0.007) and rs1041740 (HR 1.78, 95% CI 1.10-2.78, p=0.02). CONCLUSIONS: Our results are consistent with a major role for SOD1 in the mechanisms of cardiovascular protection against oxidative stress in type 2 diabetic subjects.

Plasma Adrenomedullin, Allelic Variations in the ADM Gene, and Risk for Lower-Limb Amputation in People With Type 2 Diabetes.

OBJECTIVE: Patients with diabetes have an increased risk for lower-limb amputation (LLA), but biomarkers to assess risk of LLA are lacking. Adrenomedullin (ADM) is a vasodilator peptide that also plays a role in fluid and electrolyte homeostasis in the kidney, increasing natriuresis and diuresis. ADM was shown to be associated with cardiovascular and renal events in diabetes, but it was not investigated in terms of LLA risk. We investigated the hypothesis that ADM is associated with LLA in people with type 2 diabetes. RESEARCH DESIGN AND METHODS: We studied 4,375 participants in the DIABHYCAR and SURDIAGENE cohorts (men, 68%; mean 66 years of age; mean duration of diabetes 12 years; and median follow-up 5.3 years). Plasma midregional proadrenomedullin (MR-proADM; a surrogate for ADM) was measured by immunofluorescence. Five single nucleotide polymorphisms (SNPs) in the ADM gene region were genotyped. RESULTS: LLA requirement during follow-up by increasing tertiles of plasma MR-proADM distribution was 1.0% (tertile 1 [T1]), 2.3% (T2), and 4.4% (T3) (P < 0.0001). In Cox multivariate analysis, the adjusted hazard ratio (95% CI) for LLA was 4.40 (2.30-8.88) (P < 0.0001) for T3 versus T1. Moreover, MR-proADM significantly improved indices for risk stratification of LLA. Four SNPs were associated with plasma MR-proADM concentration at baseline and with LLA during follow-up. Alleles associated with higher MR-proADM were associated with increased LLA risk. CONCLUSIONS: We observed associations of plasma MR-proADM with LLA and of ADM SNPs with plasma MR-proADM and with LLA in people with type 2 diabetes. This pattern of Mendelian randomization supports the causality of the association of ADM with LLA.

Allelic variations in superoxide dismutase-1 (SOD1) gene are associated with increased risk of diabetic nephropathy in type 1 diabetic subjects.

BACKGROUND: Oxidative stress is involved in the pathophysiology of diabetic nephropathy. The superoxide dismutase (SOD) enzymes play a major role in detoxification of reactive oxygen species and have a protective effect against diabetic nephropathy. We investigated associations of allelic variations in SOD1 gene with nephropathy in patients with type 1 diabetes. METHODS: Seven SNPs in SOD1 region were analyzed in 1285 type 1 European Caucasian diabetic patients from the SURGENE prospective study (n=340; ten year follow-up), and the Genesis France-Belgium (n=501) and GENEDIAB (n=444) cross-sectional studies. Cox proportional hazards and logistic regression analyses were used to estimate hazard ratios or odds ratios for incidence and prevalence of diabetic nephropathy. RESULTS: In the SURGENE study, the T-allele of rs1041740 was associated with the prevalence of incipient (OR 5.75, 95% CI 1.78-19.39, p=0.004) and established/advanced nephropathy at baseline (OR 8.95, 95% CI 1.51-58.42, p=0.02), and with the incidence of incipient nephropathy during follow-up (HR 1.46, 95% C.I. 1.13-1.90, p=0.004). The variant was also associated with decreased estimated glomerular filtration rate (eGFR) throughout the study. In cross-sectional study of Genesis/GENEDIAB cohorts, the G-allele of rs17880135 was associated with incipient (OR 7.53, 95% CI 2.30-25.45, p=0.001), established (OR 6.04, 95% CI 1.52-23.91, p=0.01) and advanced nephropathy (OR 10.03, 95% CI 2.95-35.44, p=0.0003). CONCLUSIONS: SOD1 allelic variations were associated with the prevalence of diabetic nephropathy, with the incidence of microalbuminuria and with decreased eGFR in type 1 diabetic subjects. These results are consistent with an implication of oxidative stress in the pathophysiology of diabetic nephropathy and with the major role for antioxidant enzymes as a mechanism of renal protection.