Effect of Vitamin D Receptor Activation on the AGE/RAGE System and Myeloperoxidase in Chronic Kidney Disease Patients

Vitamin D receptor (VDR) activation has been reported to increase circulating levels of the advanced glycation end products (AGE) and their decoy receptor (RAGE). However, until now, the effect of VDR activation on AGE and RAGE has not been tested in the setting of a randomized, double-blind clinical trial. We have therefore analyzed the effect of VDR activation by paricalcitol on pentosidine, S100A12/ENRAGE, and RAGE and on established biomarkers of oxidative stress like myeloperoxidase in CKD patients in the PENNY trial. At baseline, human S100A12/ENRAGE, RAGE, and myeloperoxidase, but not pentosidine, were intercorrelated, and the association between S100A12/ENRAGE and myeloperoxidase (r=0.71, P<0.001) was the strongest among these correlations. Paricalcitol failed to modify biomarkers of the AGE/RAGE system and myeloperoxidase in unadjusted and adjusted analyses by the generalized linear model (GLM). No effect modification by other risk factors was registered. Paricalcitol does not modify biomarkers of the AGE/RAGE system and myeloperoxidase in CKD patients. The apparent increase in RAGE levels by VDR activation reported in previous uncontrolled studies is most likely due to confounding factors rather than to VDR activation per se. This trial is registered with NCT01680198

Conversione da singoletto a tripletto della configurazione Ne2p4 in vicinanza di superfici metalliche: variazioni prodotte da deposizione di metalli alcalini e ossidazione

Dottorato di ricerca in fisica. 8. ciclo. A.a. 1995-96. Supervisore A. BonannoConsiglio Nazionale delle Ricerche - Biblioteca Centrale - P.le Aldo Moro, 7, Rome; Biblioteca Nazionale Centrale - P.za Cavalleggeri, 1, Florence / CNR - Consiglio Nazionale delle RichercheSIGLEITItal

Vitamin D and methylarginines in chronic kidney disease (CKD).

BACKGROUND:Vitamin D associates with the plasma concentration of the endogenous inhibitor of the nitric oxide system asymmetric dimethyl arginine (ADMA) and cross-sectional studies in CKD patients treated with the vitamin D receptor activator paricalcitol show that plasma ADMA is substantially less than in those not receiving this drug. METHODS:In the frame of a randomized, double-blind, placebo controlled trial, the Paracalcitol and ENdothelial fuNction in chronic kidneY disease (PENNY), we investigated whether vitamin D receptor activation by paricalcitol (2 μg/day x 12 weeks) affects the plasma concentration of ADMA and symmetric dimethyl arginine (SDMA) in 88 patients with stage 3 to 4 CKD. RESULTS:Paricalcitol produced the expected small rise in serum calcium and phosphate and a marked PTH suppression. However, ADMA [Paricalcitol: baseline 0.75 μMol/L (95%CI: 0.70-0.81), 12 week 0.72 μMol/L (95%CI: 0.66-0.78); Placebo: baseline 0.75 μMol/L (95%CI: 0.70-0.90) 12 weeks 0.70 μMol/L (95%CI: 0.66-0.74)] and SDMA [Paricalcitol: baseline 0.91 μMol/L (95%CI: 0.82-1.00), 12 week 0.94 μMol/L (95%CI: 0.82-0.1.06); Placebo: baseline 0.91 μMol/L (95%CI: 0.82-1.06) 12 weeks 0.99 μMol/L (95%CI: 0.88-1.10)] remained unchanged during the trial and 2 weeks after stopping these treatments. CONCLUSIONS:Paricalcitol does not modify plasma ADMA and SDMA in patients with stage 3-4 CKD. The apparent beneficial effects of paricalcitol on ADMA registered in cross-sectional studies is likely attributable to confounding by indication rather than to a true effect of this drug on ADMA metabolism

Association of IL-6 and a functional polymorphism in the IL-6 gene with cardiovascular events in patients with CKD

Background and objectives High serumIL-6 is amajor risk factor for cardiovascular disease (CVD) in the general population. This cytokine is substantially increased in patientswith CKD, but it is still unknownwhether the link between IL-6 and CVD in CKD is causal in nature. Design, setting, participants, & measurements In a cohort of 755 patientswith stages 2–5 CKD, consecutively recruited from 22 nephrology units in southern Italy, this study assessed the relationship of serum IL-6 with history of CVD, as well as with incident cardiovascular (CV) events (mean follow up6SD, 31610 months) and used the functional polymorphism (2174 G/C) in the promoter of the IL-6 gene to investigate whether the link between IL-6 and CV events is causal. Results In adjusted analyses, serum IL-6 above the median value was associated with history of CVD (P,0.001) and predicted the incidence rate of CV events (hazard ratio, 1.66; 95% confidence interval [95% CI], 1.11 to 2.49; P=0.01). Patients homozygous for the risk allele (C) of the2174G/C polymorphismhad higher levels of IL-6 than did those with other genotypes (P=0.04). Homozygous CC patients more frequently had a history of CVD (odds ratio, 2.15; 95%CI, 1.15 to 4.00; P=0.02) as well as a 87%higher rate of incident CV events (hazard ratio, 1.87

Serum Erythroferrone Levels Associate with Mortality and Cardiovascular Events in Hemodialysis and in CKD Patients: A Two Cohorts Study

Erythroferrone (ERFE) is a hepcidin inhibitor whose synthesis is stimulated by erythropoietin, which increases iron absorption and mobilization. We studied the association between serum ERFE and mortality and non-fatal cardiovascular (CV) events in a cohort of 1123 hemodialysis patients and in a cohort of 745 stage 1&#8211;5 chronic kidney disease (CKD) patients. Erythroferrone was measured by a validated enzyme-linked immunosorbent assay (ELISA). In the hemodialysis cohort, serum ERFE associated directly with erythropoiesis stimulating agents (ESA) dose (p &lt; 0.001) and inversely with serum iron and ferritin (p &lt; 0.001). Erythroferrone associated with the combined outcome in an analysis adjusting for traditional risk factors, factors peculiar to end-stage kidney disease, serum ferritin, inflammation, and nutritional status (HR, hazard ratio, (5 ng/mL increase: 1.04, 95% confidence interval, CI: 1.01&#8211;1.08, p = 0.005). Furthermore, treatment with ESA modified the relationship between ERFE and the combined end-point in adjusted analyses (p for the effect modification = 0.018). Similarly, in CKD patients there was a linear increase in the risk for the same outcome in adjusted analyses (HR (2 ng/mL increase): 1.04, 95% CI: 1.0&#8211;1.07, p = 0.015). Serum ERFE is associated with mortality and CV events in CKD and in HD patients, and treatment by ESA amplifies the risk for this combined end-point in HD patients

Neuropeptide Y and chronic kidney disease progression: a cohort study

Item does not contain fulltex

Smoking and hyperparathyroidism in patients with end-stage renal disease (ESRD)

Background and methods: Smoking is associated with hyperparathyroidism in the elderly general population and nicotine, the main component of tobacco smoke, stimulates PTH release in experimental models. Although smoking is a persisting problem in patients with endstage renal disease (ESRD), the association between smoking and PTH has never been specifically examined in these patients. We investigated the relationship between smoking and hyperparathyroidism in a well-characterized group of 161 nondiabetic dialysis patients. Results: Sixty-four patients (40%) were smokers. Heavy smokers had higher intact PTH (median: 280 pg/mL) and PTH 1-84 (188 pg/mL) than light smokers (180 pg/mL and 95 pg/mL) and nonsmokers (169 pg/ mL and 95