Discovery of GLO1 New Related Genes and Pathways by RNA-Seq on A2E-Stressed Retinal Epithelial Cells Could Improve Knowledge on Retinitis Pigmentosa.

Endogenous antioxidants protect cells from reactive oxygen species (ROS)-related deleterious effects, and an imbalance in the oxidant/antioxidant systems generates oxidative stress. Glyoxalase 1 (GLO1) is a ubiquitous cellular enzyme involved in detoxification of methylglyoxal (MG), a cytotoxic byproduct of glycolysis whose excess can produce oxidative stress. In retinitis pigmentosa, one of the most diffuse cause of blindness, oxidative damage leads to photoreceptor death. To clarify the role of GLO1 in retinitis pigmentosa onset and progression, we treated human retinal pigment epithelium cells by the oxidant agent A2E. Transcriptome profiles between treated and untreated cells were performed by RNA-Seq, considering two time points (3 and 6 h), after the basal one. The exposure to A2E highlighted significant expression differences and splicing events in 370 GLO1 first-neighbor genes, and 23 of them emerged from pathway clustered analysis as main candidates to be associated with retinitis pigmentosa. Such a hypothesis was corroborated by the involvement of previously analyzed genes in specific cellular activities related to oxidative stress, such as glyoxylate and dicarboxylate metabolism, glycolysis, axo-dendritic transport, lipoprotein activity and metabolism, SUMOylation and retrograde transport at the trans-Golgi network. Our findings could be the starting point to explore unclear molecular mechanisms involved in retinitis pigmentosa etiopathogenesis.

Role of oxidative stress in Retinitis pigmentosa: new involved pathways by an RNA-Seq analysis.

Retinitis pigmentosa (RP) is a very heterogeneous inherited ocular disorder group characterized by progressive retinal disruption. Retinal pigment epithelium (RPE) degeneration, due to oxidative stress which arrests the metabolic support to photoreceptors, represents one of the principal causes of RP. Here, the role of oxidative stress in RP onset and progression was analyzed by a comparative whole transcriptome analysis of human RPE cells, treated with 100 µg/ml of oxLDL and untreated, at different time points. Experiment was thrice repeated and performed on Ion ProtonTM sequencing system. Data analysis, including low quality reads trimming and gene expression quantification, was realized by CLC Genomics Workbench software. The whole analysis highlighted 14 clustered "macro-pathways" and many sub-pathways, classified by selection of 5271 genes showing the highest alteration of expression. Among them, 23 genes were already known to be RP causative ones (15 over-expressed and 8 down-expressed), and their enrichment and intersection analyses highlighted new 77 candidate related genes (49 over-expressed and 28 down-expressed). A final filtering analysis then highlighted 29 proposed candidate genes. This data suggests that many new genes, not yet associated with RP, could influence its etiopathogenesis.

Correction to: Neuropsychological Assessment in Elderly Men with Benign Prostatic Hyperplasia Treated with Dutasteride.

Catalano Antonino, Martino Gabriella, Bellone Federica, Papalia Maria, Lasco Carmen, Basile Giorgio, Sardella Alberto, Nicocia Giacomo, Morabito Nunziata, Lasco Antonino.

Neuropsychological Assessment in Elderly Men with Benign Prostatic Hyperplasia Treated with Dutasteride.

BACKGROUND AND OBJECTIVE: Benign prostatic hyperplasia (BPH) is a common disease found in elderly men and 5α-reductase (5α-R) inhibitors are a commonly used treatment option. 5α-reduced steroids are compounds that play a role in several functions across different organs and systems. In the adult brain, 5α-R accounts for neuroactive steroid production. Whether neuropsychological impairment could be due to dutasteride treatment, a 5α-R inhibitor affecting the production of dihydrotestosterone (DHT), is still unknown. The aim of our study was to investigate neuropsychological features in men receiving dutasteride. METHODS: The Mini Mental State Examination (MMSE), the Clock Drawing Test (CDT), the Frontal Assessment Battery (FAB), the Hamilton Anxiety Rating Scale (HAM-A), the Beck Depression Inventory second edition (BDI-II) and the Short Form-12 (SF-12) questionnaire were administered in order to explore both cognitive impairment and psychological features. RESULTS: In a sample of BPH patients (n = 40; mean age 71.4 ± 7.4 years), men receiving dutasteride showed no significant differences during the neuropsychological assessment in comparison with an age-matched control group, consisting of BPH men not receiving dutasteride (p < 0.05). No significant associations were recorded between treatment duration and any of the administered tests. CONCLUSIONS: This is the first study investigating the neuropsychological features in dutasteride users. Our preliminary data are consistent with the safety of dutasteride under a mental profile.

GLO1 gene polymorphisms and their association with retinitis pigmentosa: a case-control study in a Sicilian population.

Glyoxalase 1 (GLO1) is a ubiquitous cellular enzyme involved in detoxification of methylglyoxal (MGO), a cytotoxic byproduct of glycolysis, whose excess can cause oxidative stress. In retinitis pigmentosa (RP), the prevalent cause of blindness just during working life in the industrialized countries, oxidative stress represents one of the possible mechanisms leading to death of cones following that of rods in the retina. To date, the causes of secondary death of cones remain unclear and among proposed mechanisms are: the deprivation of trophic factors normally produced by healthy rods, a compromised uptake of nutrients to cones due to irreversible destruction of RPE-cone outer segment, microglial activation and following release of pro-inflammatory cytokines and rod-derived toxins. In present paper, role of oxidative stress due to an excess of MGO was evaluated. In particular, we wanted to determine whether single nucleotide polymorphisms (SNPs) in GLO1 influence enzyme activity, contributing to cone death in advanced RP. 120 healthy controls and 80 RP patients from Sicilian population were genotyped for three GLO1 common SNPs, rs1130534 (c.372A>T, p.G124G), rs2736654 (c.A332C, p.E111A) and rs1049346 (c.-7C>T, 5'-UTR). While c.A332C polymorphism was not associated with RP, c.372A>T showed an allelic association (T372 allele frequency = 70% vs 60% in controls, p = 0.0071). Conversely, c.-7C>T showed both genotypic (χ2 = 68.0952; p = 1.634e-15) and allelic associations (χ2 = 51.7094; p = 6.435e-13): mutated allele frequency was higher in controls than in patients, suggesting its possible protective role. RP susceptibility may be associated with two of the analyzed GLO1 polymorphisms (rs1130534 and rs1049346).

The combination of new missense mutation with [A(TA)7TAA] dinucleotide repeat in UGT1A1 gene promoter causes Gilbert's syndrome.

Gilbert's syndrome is a benign form of unconjugated hyperbilirubinemia caused by reduction of hepatic activity of bilirubin glucuronosyltranferase. The most common genotype of Gilbert's syndrome is the homozygous polymorphism [A(TA)7TAA] in the promoter of the gene for UDP-glucuronosyltransferase 1A1 (UGT1A1), which results in a decrease in UGT1A1 activity. However, individuals with normal bilirubin levels and no clinical symptoms of Gilbert's syndrome may also present this in a homozygous condition. By direct sequencing, we performed UGT1A1 gene analysis on a 31-year-old man with Gilbert's syndrome and homozygous for [A(TA)7TAA], and on his parents. Two UGT1A1 mutations were identified. Both mutations were inherited from each of the two parents, both with normal levels of bilirubin. One of the two mutations, c.993 (p.Q331H), is a missense mutation and is predicted to have a deleterious effect on protein functionality. Given the importance for clinicians to consider the Gilbert genotype in cases with unexplained indirect hyperbilirubinemia, the case we report may add a new variant to the spectrum of mutations of Gilbert's syndrome.

The future of phosphate binders: a perspective on novel therapeutics.

Chronic kidney disease-mineral bone disorder (CKD-MBD) is a common complication of CKD. The therapeutic strategies for the treatment of CKD-MBD include phosphate binders, active vitamin D analogs and calcimimetics. The first class of drugs provided nephrologists with a range of phosphate binders that are able to decrease circulating phosphate and parathyroid hormone but involve some tolerability and safety issues. In the past 2 years, new phosphate binders have been launched and others are still under development. Serum phosphate increases only in the late stages of CKD but clinical abnormalities begin to occur earlier when multiple mechanisms try to compensate for the progressive reduced ability of the kidney to eliminate phosphorus with urine. Accordingly, starting phosphate binders when phosphatemia reaches values higher than normal may represent a late therapeutic approach. Serum phosphorus is not the ideal biomarker for the diagnosis and treatment of phosphate imbalance. This role could be better played by fibroblast growth factor 23, whose serum concentrations rise earlier in CKD. A more detailed knowledge of the mechanisms underlying CKD-MBD development will provide new therapeutic targets and then new perspectives for the treatment of phosphate imbalance in the future.

Neutrophil gelatinase-associated lipocalin (NGAL) reflects iron status in haemodialysis patients.

BACKGROUND: An iron deficiency is often present in haemodialysis (HD) patients; however, although transferrin saturation (TSAT) of <20% and/or serum ferritin of <200 ng/mL should express iron scarcity, in HD patients high ferritin levels could be related to inflammation rather than reflecting optimal iron stores. METHODS: The aim of the present study was to evaluate serum levels of neutrophil gelatinase-associated lipocalin (NGAL), a small siderophore-binding protein, in a cohort of 56 chronic HD patients in order to determine its possible relationships with iron status. RESULTS: NGAL levels were markedly higher in HD patients than in healthy controls; furthermore, HD patients with TSAT <20% had lower NGAL values than healthy controls, whereas the correction of iron deficiency by means of chronic i.v. iron administration significantly increased NGAL values from baseline. Findings from univariate and multivariate analyses demonstrated that NGAL was a significant predictor of hsCRP, spKT/V and TSAT. In ROC analysis, a NGAL cut-off level of

Neutrophil gelatinase-associated lipocalin as an early biomarker of nephropathy in diabetic patients.

BACKGROUND/AIMS: Renal tubulointerstitium plays an important role in the development and progression of diabetic nephropathy. METHODS: With the present study, we aimed at evaluating the levels of neutrophil gelatinase-associated lipocalin (NGAL), a tubular stress protein, in serum (sNGAL) and urine (uNGAL) from a cohort of 56 patients with type 2 diabetes mellitus categorized into three groups (normoalbuminuria, microalbuminuria and diabetic nephropathy). RESULTS: All groups showed increased NGAL values with respect to controls; interestingly, increased NGAL levels were already found in diabetic patients without early signs of glomerular damage (normoalbuminuric). Both sNGAL and uNGAL increased in parallel with the severity of renal disease, reaching higher levels in patients with manifest diabetic nephropathy. The assessment of Pearson coefficient evidenced significant relationships between sNGAL and, respectively, uNGAL, serum creatinine and GFR (inversely) and between uNGAL and, respectively, serum creatinine, proteinuria, albuminuria, serum albumin and GFR (both inversely). CONCLUSIONS: NGAL might play an important role in the pathophysiology of renal adaptation to diabetes, probably as a defensive mechanism aiming to mitigate tubular suffering. Furthermore, NGAL measurement might become a useful and noninvasive tool for the evaluation of renal involvement in diabetic patients as well as for the early diagnosis of incipient nephropathy.

Increased plasma neutrophil gelatinase-associated lipocalin levels predict mortality in elderly patients with chronic heart failure.

Chronic congestive heart failure (CHF) is associated with an increase in cytokines and inflammatory markers, particularly in elderly patients in whom chronic inflammation is generally present per se. In the present pilot study, neutrophil gelatinase-associated lipocalin (NGAL), a recently discovered cytokine, was analyzed together with different clinical and laboratory parameters in a small cohort of 46 elderly patients with CHF of various degrees. NGAL levels in the cohort were found to be significantly higher than in healthy age-balanced controls (458.5 [62.5-1212.4] vs. 37.8 [15.9-46.5] ng/mL; p = 0.0001). Furthermore, NGAL values increased in parallel with the clinical severity of CHF (New York Heart Association [NYHA] classification), the highest levels being reached in class IV patients (p = 0.0001). After a 2-year follow up, Kaplan-Meier curves indicated that patients with baseline NGAL > 783 ng/mL (best receiver operating characteristic [ROC]-derived cut-off value) had a significantly higher mortality (p = 0.001; log-rank test) and 4.08 hazards ratio (95% confidence interval [CI], 1.29-12.96) for death than the other subjects considered. Although preliminary, our findings suggest that NGAL plays a pivotal role in the systemic adaptation to chronic heart failure in elderly patients. Moreover, they indicate, for the first time, that measurement of NGAL may be of important prognostic value in the assessment of survival, thus extending the predictive properties of this cytokine beyond the clinical field of renal disease.

Neutrophil gelatinase-associated lipocalin (NGAL) and progression of chronic kidney disease.

BACKGROUND AND OBJECTIVES: Chronic kidney disease (CKD) has recently assumed epidemic proportion, becoming a troubling emerging cause of morbidity, especially if it progresses to terminal stage (ESRD). The authors aimed to evaluate whether neutrophil gelatinase-associated lipocalin (NGAL), a novel specific biomarker of acute kidney injury, could predict the progression of CKD. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: Serum and urinary NGAL levels, together with a series of putative progression factors, were evaluated in a cohort of 96 patients (mean age: 57 +/- 16 years) affected by nonterminal CKD (eGFR > or =15 ml/min/1.73 m(2)) of various etiology. Progression of CKD, assessed as doubling of baseline serum creatinine and/or onset of ESRD, was evaluated during follow-up. RESULTS: At baseline, both serum and urinary NGAL were inversely, independently, and closely related to eGFR. After a median follow-up of 18.5 mo (range 1.01 to 20), 31 patients (32%) reached the composite endpoint. At baseline, these patients were significantly older and showed increased serum creatinine, calcium-phosphate product, C-reactive protein, fibrinogen, daily proteinuria, and NGAL levels, whereas eGFR values were significantly lower. Univariate followed by multivariate Cox proportional hazard regression analysis showed that urinary NGAL and sNGAL predicted CKD progression independently of other potential confounders, including eGFR and age. CONCLUSION: In patients with CKD, NGAL closely reflects the entity of renal impairment and represents a strong and independent risk marker for progression of CKD.

Effect of a single intravenous immunoglobulin infusion on neutrophil gelatinase-associated lipocalin levels in proteinuric patients with normal renal function.

The aim of the present study was to evaluate levels of neutrophil gelatinase-associated lipocalin (NGAL), a stress protein increased after renal and systemic stimuli, in a cohort of 15 patients with severe proteinuria secondary to idiopathic membranous nephropathy and conserved renal function. Neutrophil gelatinase-associated lipocalin levels and the fractional excretion of this protein were higher in patients than in healthy controls. Furthermore, a close correlation was found between serum NGAL and urinary (uNGAL) (r = 0.81; P < 0.01) and between uNGAL and daily proteinuria (r = 0.44; P < 0.03). One hour after infusion of a single high-dose bolus of intravenous immunoglobulin (0.4 g/kg), a new and promising therapy for several kidney diseases, a marked reduction was found in NGAL levels (serum NGAL 194.1 +/- 121 vs 370.1 +/- 180.5 ng/mL, P < 0.05; urinary NGAL 153.3 +/- 108.6 vs 502.2 +/- 293.4 ng/mL, P < 0.03); this was maintained 24 hours after the treatment. The findings made suggest that the NGAL balance is altered in patients with severe proteinuria who have not yet developed overt chronic renal failure, thus confirming the potential use of this protein as an early biomarker of kidney damage preceding the increase in serum creatinine levels. Furthermore, also extra-renal cells (neutrophils, endothelium) may hyper-release NGAL, expressing systemic stress related to severe proteinuria. This would explain the impressive decrease occurring in NGAL values after intravenous immunoglobulin infusion, thus providing further evidence of the antiinflammatory properties of this particular therapeutic approach and indicating the possible value of NGAL measurement in monitoring the efficacy of treatment of renal diseases.

Pathological and prognostic value of urinary neutrophil gelatinase-associated lipocalin in macroproteinuric patients with worsening renal function.

BACKGROUND/AIMS: Persistent proteinuria is a sign of renal damage caused by several factors, but it is itself a cause of tubular injury leading to chronic renal failure. Neutrophil gelatinase-associated lipocalin (NGAL) is a stress protein released by tubular cells which urinary excretion (uNGAL) increases in response to various stimuli. METHODS: In the present study we analyzed uNGAL levels in 23 macroproteinuric patients with membranous glomerulonephritis. RESULTS: In these subjects, uNGAL concentrations were significantly higher than in controls, directly correlated with proteinuria and inversely related to residual renal function. Patients were further categorized into two groups, according to a cut-off baseline uNGAL value of 350 ng/ml and evaluated during a 1-year follow-up period. After 12 months, subjects with higher uNGAL levels showed a significant worsening in baseline renal function and a 3.36 risk ratio of developing a severe decrease in GFR (>or=50% of baseline values) compared with others. CONCLUSIONS: These findings suggest that NGAL may play a key role in tubular adaptations to persistent macroproteinuria. Furthermore, a new, interesting application of NGAL measurement could be proposed in clinical nephrology as a predictor of worsening renal function in patients affected by chronic kidney disease.

Neutrophil gelatinase-associated lipocalin in patients with autosomal-dominant polycystic kidney disease.

It is known that many tubular proteins are involved in the pathogenesis of autosomal-dominant polycystic kidney disease (ADPKD), which causes 8-10% of the cases of end-stage renal disease (ESRD) worldwide. Neutrophil gelatinase-associated lipocalin (NGAL) is a protein expressed on tubular cells of which the production is markedly increased in response to harmful stimuli such as ischemia or toxicity. In the present study, serum and urinary NGAL levels were evaluated in 26 ADPKD subjects. Both levels were significantly higher in patients than in controls (sNGAL 174 +/- 52 vs. 50 +/- 27 ng/ml, p < 0.05; uNGAL 119 +/- 42 vs. 7 +/- 6 ng/ml, p < 0.005) and a close correlation was also found between these parameters and the residual renal function (sNGAL/GFR: r = -0.8, p = 0.006; sNGAL/Creatinine: r = 0.9, p = 0.007; uNGAL/GFR: r = -0.49, p < 0.05; uNGAL/Creatinine: r = 0.84, p < 0.001). Patients were further divided into two groups according to the cystic development assessed with echotomography; subjects with higher cystic growth (HCG) presented higher sNGAL and uNGAL levels with respect to others (sNGAL: 242 +/- 89 vs. 88 +/- 34 ng/ml, p < 0.05; uNGAL: 158 +/- 45 vs. 73 +/- 27 ng/ml, p < 0.05). The strict correlation between NGAL levels and residual renal function is perfectly in accord with recent studies on patients with other ESRD-associated diseases. We can hypothesize that tubular cells produce big quantities of NGAL as a consequence of increased apoptosis following chronic damage or as a compensatory response, similar to that observed in acute stress conditions (ischemia, toxicity ...). Finally, our last finding that patients with HCG showed higher levels of NGAL suggests that this protein could be also involved in the cyst growth process, as previously reported about epithelial and tumoral expansion.

Effects of atorvastatin treatment on sICAM-1 and plasma nitric oxide levels in hypercholesterolemic subjects.

This study investigated the behavior of soluble intercellular adhesion molecule-1 (sICAM-1) and serum nitric oxide (NO) products, nitrite/nitrate (NO2-/NO3-), in subjects with primary hypercholesterolemia (HCh) without other risk factors and atherosclerosis. The effect of a short-term cholesterol-lowering treatment with atorvastatin, an HMG-CoA reductase inhibitor, on the levels of sICAM-1 and NO2-/NO3- were also investigated. After 4 weeks of placebo administration, 40 HCh (15 males and 25 females) were randomized in 2 groups: 20 subjects (atorvastatin group) received 10 mg/day of atorvastatin and the remaining 20 (placebo group) continued to take placebo. At baseline and after 4 and 12 weeks of atorvastatin or placebo administration, serum sICAM-1 and NO2-/NO3-levels were evaluated. The basal levels of these parameters were compared with those of 20 healthy subjects (C), matched for sex and age. Hypercholesterolemic subjects showed sICAM-1 and NO2-/NO3- basal values that were higher (331.7 +/- 60.3 ng/mL vs. 202.3 +/- 32.3 ng/mL, p<0.001) and lower (10.4 +/- 2.5 micromol/L vs. 20.7 +/- 4.4 micromol/L, p<0.01) than controls. No correlation between sICAM-1 or NO products and plasma cholesterol values was found, whereas there was an inverse correlation between sICAM-1 and NO2-/NO3- levels. Atorvastatin administration significantly decreased sICAM-1 and increased NO2-/NO3- levels, however these changes were not correlated with the reduction of plasma cholesterol. These data support the hypothesize that patients with HCh with no signs of arterial lesions, may have latent atherosclerosis, expressed as an increase of sICAM-1 and decrease in NO product levels. An improvement in the levels of these parameters after a short-time treatment with atorvastatin was also demonstrated.

Mitogen-activated protein kinases and NF-kappa B are involved in TNF-alpha responses to group B streptococci.

TNF-alpha is a mediator of lethality in experimental infections by group B streptococcus (GBS), an important human pathogen. Little is known of signal transduction pathways involved in GBS-induced TNF-alpha production. Here we investigate the role of mitogen-activated protein kinases (MAPKs) and NF-kappa B in TNF-alpha production by human monocytes stimulated with GBS or LPS, used as a positive control. Western blot analysis of cell lysates indicates that extracellular signal-regulated kinase 1/2 (ERK 1/2), p38, and c-Jun N-terminal kinase MAPKs, as well as I kappa B alpha, became phosphorylated, and hence activated, in both LPS- and GBS-stimulated monocytes. The kinetics of these phosphorylation events, as well as those of TNF-alpha production, were delayed by 30-60 min in GBS-stimulated, relative to LPS-stimulated, monocytes. Selective inhibitors of ERK 1/2 (PD98059 or U0126), p38 (SB203580), or NF-kappa B (caffeic acid phenetyl ester (CAPE)) could all significantly reduce TNF-alpha production, although none of the inhibitors used alone was able to completely prevent TNF-alpha release. However, this was completely blocked by combinations of the inhibitors, including PD98059-SB203580, PD98059-CAPE, or SB203580-CAPE combinations, in both LPS- and GBS-stimulated monocytes. In conclusion, our data indicate that the simultaneous activation of multiple pathways, including NF-kappa B, ERK 1/2, and p38 MAPKs, is required to induce maximal TNF-alpha production. Accordingly, in septic shock caused by either GBS or Gram-negative bacteria, complete inhibition of TNF-alpha release may require treatment with drugs or drug combinations capable of inhibiting multiple activation pathways.

The anti-tumor activity of bacillus Calmette-Guerin in bladder cancer is associated with an increase in the circulating level of interleukin-2.

Bacillus Calmette-Guerin (BCG) is currently employed in the treatment of superficial bladder cancer but, despite its recognized effectiveness in preventing recurrences and progression, the immune mechanisms behind its antitumor activity remain to be delineated. In this study we provide evidence that a prolonged increase in the plasma levels of IL-2, but not IL-1beta, IL-4, IL-10, IL-2R or TNF-alpha occured in patients affected by bladder cancer following effective BCG treatment. Conversely, a drop in circulating IL-2 was consistently associated with tumor relapse. The level of IL-2 was elevated even further 15 days after the last BCG administration in patients who did not experience tumor recurrence, suggesting a prolonged T cell-mediated response against antigens other than BCG. Our results indicate that a specific type 1 immune response plays a major role in the anti-cancer activity of BCG. In addition, monitoring IL-2 plasma levels may offer a useful tool for predicting tumor recurrences.

Adiponectin, metabolic risk factors, and cardiovascular events among patients with end-stage renal disease.

Adiponectin (ADPN), which is a secretory protein of adipose tissue, attenuates endothelial inflammatory responses in vitro. Among human subjects, plasma ADPN concentrations are reduced among patients with atherosclerotic complications but are substantially increased among patients with advanced renal failure. The clinical and biochemical correlates of plasma ADPN levels were investigated and the predictive power of ADPN levels with respect to survival rates and cardiovascular events was prospectively tested in a cohort of 227 hemodialysis patients, who were monitored for 31 +/- 13 mo. Plasma ADPN levels were 2.5 times higher (P < 0.0001) among dialysis patients (15.0 +/- 7.7 microg/ml) than among healthy subjects (6.3 +/- 2.0 microg/ml), were independent of age, and were higher (P = 0.03) among women (15.2 +/- 7.9 microg/ml) than among men (14.0 +/- 7.4 microg/ml). For both genders, plasma ADPN levels were inversely related to body mass index values, plasma leptin levels, insulin levels, serum triglyceride levels, and homeostatic model assessment index values. Furthermore, plasma ADPN levels were directly related to HDL cholesterol levels and inversely related to von Willebrand factor levels. Plasma ADPN levels were lower (P < 0.05) among patients who experienced new cardiovascular events (13.7 +/- 7.3 microg/ml) than among event-free patients (15.8 +/- 7.8 microg/ml). There was a 3% risk reduction for each 1 microg/ml increase in plasma ADPN levels, and the relative risk of adverse cardiovascular events was 1.56 times (95% confidence interval, 1.12 to 1.99 times) higher among patients in the first ADPN tertile, compared with those in the third tertile. Plasma ADPN levels are an inverse predictor of cardiovascular outcomes among patients with end-stage renal disease. Furthermore, ADPN is related to several metabolic risk factors in a manner consistent with the hypothesis that this protein acts as a protective factor for the cardiovascular system.