Genome-Wide Association Analysis of Protein-Coding Variants in IgA Nephropathy.

SIGNIFICANCE STATEMENT: Genome-wide association studies have identified nearly 20 IgA nephropathy susceptibility loci. However, most nonsynonymous coding variants, particularly ones that occur rarely or at a low frequency, have not been well investigated. The authors performed a chip-based association study of IgA nephropathy in 8529 patients with the disorder and 23,224 controls. They identified a rare variant in the gene encoding vascular endothelial growth factor A (VEGFA) that was significantly associated with a two-fold increased risk of IgA nephropathy, which was further confirmed by sequencing analysis. They also identified a novel common variant in PKD1L3 that was significantly associated with lower haptoglobin protein levels. This study, which was well-powered to detect low-frequency variants with moderate to large effect sizes, helps expand our understanding of the genetic basis of IgA nephropathy susceptibility. BACKGROUND: Genome-wide association studies have identified nearly 20 susceptibility loci for IgA nephropathy. However, most nonsynonymous coding variants, particularly those occurring rarely or at a low frequency, have not been well investigated. METHODS: We performed a three-stage exome chip-based association study of coding variants in 8529 patients with IgA nephropathy and 23,224 controls, all of Han Chinese ancestry. Sequencing analysis was conducted to investigate rare coding variants that were not covered by the exome chip. We used molecular dynamic simulation to characterize the effects of mutations of VEGFA on the protein's structure and function. We also explored the relationship between the identified variants and the risk of disease progression. RESULTS: We discovered a novel rare nonsynonymous risk variant in VEGFA (odds ratio, 1.97; 95% confidence interval [95% CI], 1.61 to 2.41; P = 3.61×10 -11 ). Further sequencing of VEGFA revealed twice as many carriers of other rare variants in 2148 cases compared with 2732 controls. We also identified a common nonsynonymous risk variant in PKD1L3 (odds ratio, 1.16; 95% CI, 1.11 to 1.21; P = 1.43×10 -11 ), which was associated with lower haptoglobin protein levels. The rare VEGFA mutation could cause a conformational change and increase the binding affinity of VEGFA to its receptors. Furthermore, this variant was associated with the increased risk of kidney disease progression in IgA nephropathy (hazard ratio, 2.99; 95% CI, 1.09 to 8.21; P = 0.03). CONCLUSIONS: Our study identified two novel risk variants for IgA nephropathy in VEGFA and PKD1L3 and helps expand our understanding of the genetic basis of IgA nephropathy susceptibility.

Identification and functional characterization of the first deep intronic GLA mutation (IVS4+1326C>T) causing renal variant of Fabry disease.

BACKGROUND: Fabry disease (FD, OMIM #301500) is an X-linked lysosomal disorder caused by the deficiency of α-galactosidase A (α-GalA), encoded by the GLA gene. Among more than 1100 reported GLA mutations, few were deep intronic mutations which have been linked to classic and cardiac variants of FD. METHODS AND RESULTS: We report a novel hemizygous deep intronic GLA mutation (IVS4+1326C>T) in a 33-year-old Chinese man with a mild α-GalA deficiency phenotype involving isolated proteinuria and predominant globotriaosylceramide deposits in podocytes. IVS4+1326C>T, which appears to be the first deep intronic GLA mutation associated with renal variant of FD, was identified by Sanger sequencing the entire GLA genomic DNA sequence of the patient's peripheral mononuclear blood lymphocytes (PBMCs). Further sequencing of cDNA from PBMCs of the patient revealed a minor full-length GLA transcript accounting for about 25% of total GLA transcript, along with two major aberrantly spliced GLA transcripts encoding mutant forms of α-GalA with little enzyme activity characterized by in vitro α-GalA overexpression system in the HEK293T cells. Thus, the combined clinical phenotype, genetic analysis and functional studies verified the pathogenicity of IVS4+1326C>T. CONCLUSIONS: The identification of IVS4+1326C>T establishes a link between deep intronic GLA mutation and the renal variant of FD, which extends the mutation spectrum in GLA gene and justifies further study of how IVS4+1326C>T and potentially other deep intronic GLA mutations contribute to Fabry podocytopathy through aberrant splicing. Future studies should also assess the true incidence of IVS4+1326C>T in patients with different variants of FD, which may improve early genetic diagnosis to allow timely treatment that can prevent disease progression and improve survival.

Efficacy and safety of Shenyankangfu Tablet, a Chinese patent medicine, for primary glomerulonephritis: A multicenter randomized controlled trial.

BACKGROUND: Shenyankangfu Tablet (SYKFT) is a Chinese patent medicine that has been used widely to decrease proteinuria and the progression of chronic kidney disease. OBJECTIVE: This trial compared the efficacy and safety of SYKFT, for the control of proteinuria in primary glomerulonephritis patients, against the standard drug, losartan potassium. DESIGN, SETTING, PARTICIPANTS AND INTERVENTION: This was a multicenter, double-blind, randomized, controlled clinical trial. Primary glomerulonephritis patients, aged 18-70 years, with blood pressure ≤ 140/90 mmHg, estimated glomerular filtration rate (eGFR) ≥ 45 mL/min per 1.73 m2, and 24-hour proteinuria level of 0.5-3.0 g, were recruited in 41 hospitals across 19 provinces in China and were randomly divided into five groups: SYKFT, losartan potassium 50 mg or 100 mg, SYKFT plus losartan potassium 50 mg or 100 mg. MAIN OUTCOME MEASURES: The primary outcome was change in the 24-hour proteinuria level, after 48 weeks of treatment. RESULTS: A total of 735 participants were enrolled. The percent decline of urine protein quantification in the SYKFT group after 48 weeks was 8.78% ± 2.56% (P = 0.006) more than that in the losartan 50 mg group, which was 0.51% ± 2.54% (P = 1.000) less than that in the losartan 100 mg group. Compared with the losartan potassium 50 mg group, the SYKFT plus losartan potassium 50 mg group had a 13.39% ± 2.49% (P < 0.001) greater reduction in urine protein level. Compared with the losartan potassium 100 mg group, the SYKFT plus losartan potassium 100 mg group had a 9.77% ± 2.52% (P = 0.001) greater reduction in urine protein. With a superiority threshold of 15%, neither was statistically significant. eGFR, serum creatinine and serum albumin from the baseline did not change statistically significant. The average change in TCM syndrome score between the patients who took SYKFT (-3.00 [-6.00, -2.00]) and who did not take SYKFT (-2.00 [-5.00, 0]) was statistically significant (P = 0.003). No obvious adverse reactions were observed in any group. CONCLUSION: SYKFT decreased the proteinuria and improved the TCM syndrome scores of primary glomerulonephritis patients, with no change in the rate of decrease in the eGFR. SYKFT plus losartan potassium therapy decreased proteinuria more than losartan potassium therapy alone. TRIAL REGISTRATION NUMBER: NCT02063100 on ClinicalTrials.gov.

Decreased KLHL3 expression is involved in the activation of WNK-OSR1/SPAK-NCC cascade in type 1 diabetic mice.

Familial hyperkalemic hypertension (FHHt; also called pseudohypoaldosteronism type II) is a hereditary hypertensive disease which can be caused by mutations in four genes: WNK1 [with no lysine (K) 1], WNK4, Kelch-like3 (KLHL3), and cullin3 (CUL3). Decreased KLHL3 expression was identified as being involved in the pathogenesis of FHHt caused by cullin 3 disease mutations. Recent studies have revealed an increased WNK4 and hence Na-Cl cotransporter (NCC) activity in the db/db mice, resulting from PKC-mediated KLHL3 phosphorylation, which impairs the degradation of its substrate, WNK4. However, whether WNK4 and NCC were activated in type 1 diabetes still remains unclear. We created streptozotocin-induced type 1 diabetic mice and revealed that renal WNK-oxidative stress response kinase-1/STE20/SPS1-related proline alanine-rich kinase (OSR1/SPAK)-NCC cascade was activated, whereas KLHL3 expression was markedly decreased and CUL3 was heavily neddylated. Moreover, decreased KLHL3 was reversed and WNK1 and WNK4 abundance increased by MLN4924, a neddylation inhibitor. In vitro, our study also showed decreased KLHL3 abundance without any significant change in phosphorylated KLHL3 under high glucose exposure. These results indicate that decreased KLHL3 likely plays a role in the pathogenesis of renal sodium reabsorption in hyperglycemic conditions.

Genome-Wide Meta-Analysis Identifies Three Novel Susceptibility Loci and Reveals Ethnic Heterogeneity of Genetic Susceptibility for IgA Nephropathy.

BACKGROUND: Eighteen known susceptibility loci for IgAN account for only a small proportion of IgAN risk. METHODS: Genome-wide meta-analysis was performed in 2628 patients and 11,563 controls of Chinese ancestry, and a replication analysis was conducted in 6879 patients and 9019 controls of Chinese descent and 1039 patients and 1289 controls of European ancestry. The data were used to assess the association of susceptibility loci with clinical phenotypes for IgAN, and to investigate genetic heterogeneity of IgAN susceptibility between the two populations. Imputation-based analysis of the MHC/HLA region extended the scrutiny. RESULTS: Identification of three novel loci (rs6427389 on 1q23.1 [P=8.18×10-9, OR=1.132], rs6942325 on 6p25.3 [P=1.62×10-11, OR=1.165], and rs2240335 on 1p36.13 [P=5.10×10-9, OR=1.114]), implicates FCRL3, DUSP22.IRF4, and PADI4 as susceptibility genes for IgAN. Rs2240335 is associated with the expression level of PADI4, and rs6427389 is in high linkage disequilibrium with rs11264799, which showed a strong expression quantitative trail loci effect on FCRL3. Of the 24 confirmed risk SNPs, six showed significant heterogeneity of genetic effects and DEFA showed clear evidence of allelic heterogeneity between the populations. Imputation-based analysis of the MHC region revealed significant associations at three HLA polymorphisms (HLA allele DPB1*02, AA_DRB1_140_32657458_T, and AA_DQA1_34_32717152) and two SNPs (rs9275464 and rs2295119). CONCLUSIONS: A meta-analysis of GWAS data revealed three novel genetic risk loci for IgAN, and three HLA polymorphisms and two SNPs within the MHC region, and demonstrated the genetic heterogeneity of seven loci out of 24 confirmed risk SNPs.  These variants may explain susceptibility differences between Chinese and European populations.

Effect of Sheng Xue Ning Tablets on Renal Anemia in Patients Subject to Maintenance Hemodialysis and Safety Evaluation: A Multi-setting Prospective Randomized Study.

This study compared Sheng Xue Ning (SXN) tablets with ferrous succinate (FS) tablets in terms of their efficacy for the treatment of iron-deficient renal anemia and safety in patients subject to maintenance hemodialysis (MHD). A total of 94 patients undergoing MHD were randomly assigned to an experiment group (receiving oral SXN tablets, SXN group) and a control group (orally given FS tablets, FS group) and followed up for 12 weeks. Erythropoietin (EPO) was used in both groups. The efficacy was assessed by detecting the subsequent changes in hemoglobin (Hb), serum iron (SI), SF and transferrin saturation (TSAT). At the 12th week, Hb and TSAT levels in both groups were significantly increased compared to those in the screening period (P<0.05). However, no significant difference in Hb and TSAT was found between the two groups. The average weekly EPO dosage used was lower in SXN group than in FS group (P<0.05) at the 10th week and the 12th week. Our study showed that SXN tablets can effectively ameliorate renal anemia and keep iron metabolism stable in MHD patients, and its efficacy is virtually close to that of FS tablets. Meanwhile, SXN tablets can reduce the dosage of EPO and have a good safety profile.

De novo Cardiac Valve Calcification after Hemodialysis in End-Stage Renal Disease Patients Predicts Future Cardiovascular Events: A Longitudinal Cohort Study.

BACKGROUND: Cardiac valve calcification (CVC) in maintenance hemodialysis patients is associated with adverse cardiovascular outcomes. However, whether de novo CVC in incident hemodialysis patients predicts future cardiovascular events is unknown. METHODS: This study included 174 patients newly receiving hemodialysis without CVC as reflected by echocardiography between January 2005 and December 2014. De novo CVC was determined with echocardiography once every 6 months until December 2016. RESULTS: The median follow-up was 66 months (range, 19-141). De novo CVC developed in 80 out of 174 (45.98%) subjects: 58 developed aortic valve calcification (AVC) alone, 42 developed mitral valve calcification (MVC) alone, and 20 developed both AVC and MVC. The median time from baseline to de novo CVC was 46 months (range, 3-120) for AVC and 50 months (range, 13-127) for MVC. Patients who developed CVC had a higher major adverse cardiovascular events (MACE) rate than those who did not (AVC: 30/58 [51.72%] vs. 23/116 [19.83%]; MVC: 25/42 [59.52%] vs. 28/132 [21.21%]). Multivariate time-dependent Cox regression showed an association between MACE with both de novo AVC and MVC (AVC: hazard ratio [HR] 3.2, 95% confidence interval [CI] 1.55-6.63; MVC: HR 5.95, 95% CI 2.90-12.20). CONCLUSIONS: De novo CVC is an independent risk factor for MACE in hemodialysis patients, and regular CVC screening among hemodialysis patients without preexisting CVC may be helpful to identify patients at increased risk of adverse cardiovascular outcomes.

First identification of PODXL nonsense mutations in autosomal dominant focal segmental glomerulosclerosis.

Recently, a novel heterozygous missense mutation c.T1421G (p. L474R) in the PODXL gene encoding podocalyxin was identified in an autosomal dominant focal segmental glomerulosclerosis (AD-FSGS) pedigree. However, this PODXL mutation appeared not to impair podocalyxin function, and it is necessary to identify new PODXL mutations and determine their causative role for FSGS. In the present study, we report the identification of a heterozygous nonsense PODXL mutation (c.C976T; p. Arg326X) in a Chinese pedigree featured by proteinuria and renal insufficiency with AD inheritance by whole exome sequencing (WES). Total mRNA and PODXL protein abundance were decreased in available peripheral blood cell samples of two affected patients undergoing hemodialysis, compared with those in healthy controls and hemodialysis controls without PODXL mutation. We identified another novel PODXL heterozygous nonsense mutation (c.C1133G; p.Ser378X) in a British-Indian pedigree of AD-FSGS by WES. In vitro study showed that, human embryonic kidney 293T cells transfected with the pEGFP-PODXL-Arg326X or pEGFP-PODXL-Ser378X plasmid expressed significantly lower mRNA and PODXL protein compared with cells transfected with the wild-type plasmid. Blocking nonsense-mediated mRNA decay (NMD) significantly restored the amount of mutant mRNA and PODXL proteins, which indicated that the pathogenic effect of PODXL nonsense mutations is likely due to NMD, resulting in podocalyxin deficiency. Functional consequences caused by the PODXL nonsense mutations were inferred by siRNA knockdown in cultured podocytes and podocalyxin down-regulation by siRNA resulted in decreased RhoA and ezrin activities, cell migration and stress fiber formation. Our results provided new data implicating heterozygous PODXL nonsense mutations in the development of FSGS.

Safety, Effectiveness, and Manipulability of Peritoneal Dialysis Machines Made in China: A Randomized, Crossover, Multicenter Clinical Study.

BACKGROUND: Automated peritoneal dialysis (APD) can cater to individual needs, provide treatment while asleep, take into account the adequacy of dialysis, and improve the quality of life. Currently, independent research and development of APD machines made in China are more conducive to patients. A randomized, multicenter, crossover study was conducted by comparing an APD machine made in China with an imported machine. The safety, effectiveness, and manipulability of the two machines were compared. METHODS: Two hundred and sixty patients who underwent peritoneal dialysis (PD) on a regular basis in 18 centers between August 2015 and February 2016 were included. The inclusion criteria include age ≥18 years and PD ≥30 days. The exclusion criteria were as follows: hemodialysis; exit site or tunnel infection; and peritonitis ≤30 days. The patients were randomly divided into Group A, who were first treated with a FM machine made in China, then changed to an imported machine; and Group B, who were treated using the reverse sequence. APD treatment was performed with 10 L/10 h and 5 cycles of exchange. After 72 h, the daily peritoneal Kt/V, the accuracy of the injection rate, accuracy of the injection temperature, safety, and manipulability of the machine were assessed. Noninferiority test was conducted between the two groups. RESULTS: The daily peritoneal Kt/V in the APD machine made in China and the imported APD machine were 0.17 (0.14, 0.25) and 0.16 (0.13, 0.23), respectively. There was no significant difference between the groups (Z = 0.15, P = 0.703). The lower limit of the daily Kt/V difference between the two groups was 0.0069, which was greater than the noninferiority value of -0.07 in this study. The accuracy of the injection rate and injection temperature was 89.7% and 91.5%, respectively, in the domestic APD machine, which were both slightly better than the accuracy rates of 84.0% and 86.8% in the imported APD machine (89.7% vs. 84.0%, P = 0.2466; 91.5% vs. 86.8%, P = 0.0954). Therefore, the APD machine made in China was not inferior to the imported APD machine. The fuselage of the imported APD machine was space-saving, while the APD machine made in China was superior with respect to body mobility, man-machine dialog operation, alarm control, and patient information recognition. CONCLUSIONS: The FM machine made in China was not inferior to the imported APD machine. In addition, the FM machine made in China had better operability. TRIAL REGISTRATION: Clinicaltrials.gov, NCT02525497; https://clinicaltrials.gov/ct2/results?cond=&term=NCT02525497&cntry=& state=&city=&dist=.

Randomised, open-label, multicentre trial comparing haemodialysis plus haemoperfusion versus haemodialysis alone in adult patients with end-stage renal disease (HD/HP vs HD): study protocol.

INTRODUCTION: Haemodialysis (HD) is the cornerstone treatment for patients with end-stage renal disease (ESRD). However, highly protein bound or large molecular weight uremic toxins such as phenolic and indolic compounds and homocysteine, which are associated with adverse outcomes such as cardiovascular disease of patients with ESRD, are difficult to remove via HD but can be effectively eliminates by haemoperfusion (HP). The proposed trial (referred to as HD/HP vs HD below) is a randomised, open-label, multicentre trial comparing HD plus HP versus HD alone in adult patients with ESRD. The primary endpoint measure is all-cause mortality. METHODS AND ANALYSIS: We plan to enrol 1364 maintenance HD patients from 11 medical centres in Shanghai. Participants will be randomised to receive HD plus HP or HD alone at a 1:1 ratio after 1-month run-in period. In both arms, patients will receive low-flux HD at a frequency of two times a week and haemodiafiltration at a frequency of once a week. In the intervention group, subjects also received HP once every 2 weeks. Follow-up is scheduled at 3, 6, 12, 18 and 24 months after randomisation, and will consist the following: routine physical examinations, standard lab panels (blood routine, liver/residual kidney functions, tests of the coagulation system, etc), dialysis adequacy (standard Kt/V), chest X-ray, ECG, echocardiography, heart function rating. Adverse events will be assessed according to the international conference on harmonisation guidelines. The primary outcome is 24-month all-cause mortality. Secondary outcomes will include cardiovascular-related mortality, the occurrence of major cardiovascular events and the quality of life. ETHICS AND DISSEMINATION: The study protocol has been approved by the Ethical Committees of all 11 participating centres. Clinical Research Unit of Xin Hua Hospital will oversee the study. The results will be presented at national and international academic meetings, and submitted to peer-reviewed journals for publications. TRIAL REGISTRATION NUMBER: NCT03227770; Pre-results.

Impact of hemoglobin variability on cardiovascular mortality in maintenance hemodialysis patients.

PURPOSE: Although the association between anemia and cardiovascular mortality in hemodialysis patients is well established, whether hemoglobin variability (Hgb-Var) affects the prognosis remains unclear. We aimed to evaluate the association between Hgb-Var and cardiovascular mortality in Chinese hemodialysis patients. METHODS: This retrospective study included 252 patients starting hemodialysis in Xin Hua Hospital between January 2009 and December 2015. Patients were divided into three tertiles based on Hgb-Var, as reflected by SD Hgbmean, SD Hgbrange, and Hgbdeflection during a 12-month evaluation period after hemodialysis initiation. Left ventricular ejection fraction (EF) and left ventricular mass index (LVMI) were evaluated by echocardiography. Information on cardiovascular deaths occurred by December 2017 was collected. Multivariate Cox regression models were constructed to evaluate the association between Hgb-Var and cardiovascular mortality. RESULTS: A total of 75 deaths and 52 cardiovascular deaths occurred during the 47-month follow-up (range 29.5-70). Under multivariate regression, the subgroup with the highest Hgb-Var had a higher risk of cardiovascular mortality after adjusting for relevant factors (HR vs. lowest SD Hgbmean: 9.15, 95% CI 2.82, 29.693, P < 0.0001; HR vs. lowest SD Hgbrange: 3.81, 95% CI 1.40, 10.38, P = 0.005). Per 1 SD of Hgbmean and Hgbrange elevations were both related to a 10% increase in the cardiovascular mortality risk. Baseline EF% and LVMI did not differ across the Hgb-Var subgroups. EF% upon the last patient visit to the clinic was lower in the subgroup with the highest SD Hgbmean (P = 0.02). CONCLUSIONS: High Hgb-Var is an independent risk factor for cardiovascular mortality in hemodialysis patients and might influence the cardiac function.

Resveratrol attenuates skeletal muscle atrophy induced by chronic kidney disease via MuRF1 signaling pathway.

Skeletal muscle atrophy is an important clinical characteristic of chronic kidney disease (CKD); however, at present, the therapeutic approaches to muscle atrophy induced by CKD are still at an early stage of development. Resveratrol is used to attenuate muscle atrophy in other experimental models, but the effects on a CKD model are largely unknown. Here, we showed that resveratrol prevented an increase in MuRF1 expression and attenuated muscle atrophy in vivo model of CKD. We also found that phosphorylation of NF-κB was inhibited at the same time. Dexamethasone-induced MuRF1 upregulation was significantly attenuated in C2C12 myotubes by resveratrol in vitro, but this effect on C2C12 myotubes was abrogated by a knockdown of NF-κB, suggesting that the beneficial effect of resveratrol was NF-κB dependent. Our findings provide novel information about the ability of resveratrol to prevent or treat muscle atrophy induced by CKD.

Combination therapy with lamivudine and angiotensin-converting enzyme inhibitor/angiotensin receptor blocker for hepatitis B virus-associated glomerulonephritis with mild to moderate proteinuria: a clinical review of 38 cases.

PURPOSE: The treatment of HBV-associated glomerulonephritis (HBV-GN) is still a challenge in clinical practice now. The objective of this study was to report the pathological characteristics of HBV-GN presenting with mild to moderate proteinuria and to evaluate the therapeutic efficacy of lamivudine (LAM) in combination with angiotensin-converting enzyme inhibitor (ACEI)/angiotensin receptor blocker (ARB) as compared to ACEI/ARB monotherapy. METHODS: We conducted a retrospective observational study in HBV-GN patients between 2005 and 2014. The patients were classified into two groups: Group 1 included patients treated with LAM plus ACEI/ARB (n = 20), and group 2, patients treated with ACEI/ARB alone (n = 18). Their clinical and pathological characteristics were collected; we analyzed the therapeutic responses and assessed the correlation between renal and liver pathologies. RESULTS: Our results showed that the most common type of HBV-GN was IgA nephropathy. LAM plus ACEI/ARB therapy was better in reducing 24-h urinary protein excretion, alanine aminotransferase, and aspartate aminotransferase levels, while maintaining the level of kidney function. The proportion of patients who achieved remission (CR + PR) was higher in the LAM plus ACEI/ARB group than in the ACEI/ARB monotherapy group (χ 2 = 5.371, P = 0.035). CONCLUSION: In the HBV-GN patients with mild to moderate proteinuria, LAM plus ACEI/ARB not only improved liver function but also better reduced 24-h proteinuria.

Effects of mineralocorticoid receptor antagonists on the progression of diabetic nephropathy.

AIMS/INTRODUCTION: We aimed to evaluate the potential benefits and adverse effects of adding a mineralocorticoid receptor antagonist (MRA) to angiotensin-converting enzyme inhibitors (ACEI) and/or angiotensin receptor blockers (ARB), as standard treatment in patients with diabetic nephropathy. MATERIALS AND METHODS: We scanned the Embase, PubMed and Cochrane Central Register of Controlled Trials databases for human clinical trials published in English until June 2016, evaluating renal outcomes in patients with diabetic nephropathy. RESULTS: A total of 18 randomized controlled trials involving 1,786 patients were included. Compared with ACEI/ARB alone, co-administration of MRA and ACEI/ARB significantly reduced urinary albumin excretion and the urinary albumin-creatinine ratio (mean difference -69.38, 95% confidence intervals -103.53 to -35.22, P < 0.0001; mean difference -215.74, 95% confidence intervals -409.22 to -22.26, P = 0.03, respectively). A decrease of blood pressure was also found in the co-administration of MRA and ACEI/ARB groups. However, we did not observe any improvement in the glomerular filtration rate. There was a significant increase in the risk of hyperkalemia on the addition of MRA to ACEI/ARB treatment (relative risk 3.74, 95% confidence intervals 2.30-6.09, P < 0.00001). CONCLUSIONS: These findings suggest that co-administration of MRA and ACEI/ARB has beneficial effects on renal outcomes with increasing the incidence of hyperkalemia.

miR-204 regulates epithelial-mesenchymal transition by targeting SP1 in the tubular epithelial cells after acute kidney injury induced by ischemia-reperfusion.

Acute kidney injury (AKI) is a disease where kidney function is lost almost instantaneously; it can develop very rapidly over few hours to maximum of few days. Despite the advent of technology, the clinical management against this disease is very poor, and most of the time it is life-threatening. AKI has been actively regulated by extracellular matrix proteins (ECM), however, its underlying mechanism of regulation during AKI progression is very poorly understood. In this study, we explored the integrated network of mRNA and microRNAs (miRNAs) that maintains the progression of ECM after induction of AKI by lethal ischemia. To identify key regulators of ECM, we screened large number of transcriptomes using laser capture microdissection (LCM) technique in addition to microarray and RT-qPCR. Our result clearly showed that 9 miRNAs including miR-21, miR-483, miR-5115, miR-204e, miR-128, miR-181c, miR-203, miR-204 and miR-204c were highly regulated, out of which miR-204 expression change (decrease) was most drastic during ischemia/reperfusion. Detail mechanistic study utilizing combined experimental and computational approach revealed that TGF-ß signaling pathway was potentially modulated by deregulated miRNA-204 through SP1, where the TGF-ß signaling pathway plays a vital role in ECM regulation. Apart from targeting SP1 and antagonizing epithelial-mesenchymal transition (EMT) signaling our result also showed that miR-204 protects interstitial tissue of renal tubules from chronic fibrotic change. Altogether our study provides sufficient details of how miRNA mediated ECM regulation occur during AKI, which can be effectively utilized in future for better AKI management and diagnosis.

Serum phosphorus is related to left ventricular remodeling independent of renal function in hospitalized patients with chronic kidney disease.

BACKGROUND: Increasing evidence indicated that phosphorus emerged as an important cardiovascular risk factor in patients with chronic kidney disease (CKD). The fact that serum phosphorus was closely linked to vascular and valvar calcification may account for one important reason. However, left ventricular remodeling may also serve as another potential mechanism of the cardiac toxicity of phosphorus. In the present study, we evaluated the association of serum phosphorus with left ventricular remodeling. METHODS: We investigated consecutive hospitalized patients with pre-dialysis CKD, who did not have symptomatic heart failure or take any phosphorus binder or calcitriol medications. Transthoracic echocardiography was applied to assess their left ventricular remodeling indices, both structural and functional. RESULTS: The 296 study subjects (mean age 56.4years) included 169 (57.1%) men, 203 (68.6%) hypertensive patients. In addition to gender, systolic blood pressure, and estimated glomerular filtration rate, serum phosphorus was an independent determinant of left ventricular mass index (LVMI, P=0.001). Similarly, serum phosphorus was also a determinant of left ventricular end diastolic dimension (P=0.0003), but not of relative wall thickness. In multivariate logistic analyses, serum phosphorus was significantly and independently associated with the prevalence of left ventricular hypertrophy (LVH, odds ratio [OR] 2.38 for each 1mmol/L increase, 95% CI 1.20-4.75, P=0.01). Moreover, the association was only confirmatory in eccentric LVH (OR 3.01, 95% CI 1.43-6.32, P=0.003) but not in concentric LVH (1.38, 95% CI, 0.54-3.49, P=0.50). CONCLUSION: Serum phosphorus was significantly and independently associated with LVMI and the prevalence of eccentric LVH in hospitalized patients with CKD.

Prevalence, awareness, and treatment of anemia in Chinese patients with nondialysis chronic kidney disease: First multicenter, cross-sectional study.

This was the first multicenter, cross-sectional survey to assess the prevalence of anemia, patient awareness, and treatment status in China. Data of patients with chronic kidney disease (CKD; age, 18-75 years; both out- and inpatients) from 25 hospitals in Shanghai, seeking medical treatment at the nephrology department, were collected between July 1, 2012 and August 31, 2012. The prevalence, awareness, and treatment of anemia in patients with nondialysis CKD (ND-CKD) were assessed. Anemia was defined as serum hemoglobin (Hb) levels ≤12 g/dL in women and ≤13 g/dL in men. A total of 2420 patients with ND-CKD were included. Anemia was established in 1246 (51.5%) patients: 639 (51.3%) men and 607 (48.7%) women. The prevalence of anemia increased with advancing CKD stage (χtrend = 675.14, P < 0.001). Anemia was more prevalent in patients with diabetic nephropathy (68.0%) than in patients with hypertensive renal damage (56.6%) or chronic glomerulonephritis (46.1%, both P < 0.001). Only 39.8% of the anemic patients received treatment with erythropoietin and 27.1% patients received iron products; furthermore, 22.7% of the patients started receiving treatment when their Hb level reached 7 g/dL. The target-achieving rate (Hb at 11-12 g/dL) was only 8.2%. Of the 1246 anemia patients, only 7.5% received more effective and recommended intravenous supplementation. Anemia is highly prevalent in patients with ND-CKD in China, with a low target-achieving rate and poor treatment patterns. The study highlights the need to improve multiple aspects of CKD management to delay the progression of renal failure.

Delayed diagnosis of Townes-Brocks syndrome with multicystic kidneys and renal failure caused by a novel SALL1 nonsense mutation: A case report.

Townes-Brocks syndrome (TBS) is a rare autosomal dominant congenital anomaly syndrome characterized by the triad of anorectal, hand and external ear malformations. Kidney involvement is less common and may progress to end-stage renal failure (ESRF) early in life. The present study reports the case of a male patient presenting with multiple bilateral cortical kidney cysts at the age of 4 years, at which time the kidneys were of normal size and function. A clinical diagnosis of autosomal recessive polycystic kidney disease was made initially as the patient's parents are clinically healthy. However, the consideration of extra-renal involvements (imperforate anus at birth, preaxial polydactyly and dysplastic right ear) following the progression of the patient to ESRF at the age of 16 years, led to the diagnosis of TBS. This prompted sequencing of the SALL1 gene, which identified a novel heterozygous nonsense mutation in the mutational 'hotspot' of exon 2 (c.874C>T, p.Q292X), and this mutation was not detected in healthy controls. The current case highlights that TBS may present with normal sized, cystic kidneys in childhood, while recognition of extra-renal features of cystic kidney diseases, such as TBS, and genetic testing may facilitate the correct diagnosis and transmission mode. Reaching a correct diagnosis of as TBS is important since this condition has a 50% rate of transmission to offspring and can progress to ESRF early in life.

Identification of new susceptibility loci for IgA nephropathy in Han Chinese.

IgA nephropathy (IgAN) is one of the most common primary glomerulonephritis. Previously identified genome-wide association study (GWAS) loci explain only a fraction of disease risk. To identify novel susceptibility loci in Han Chinese, we conduct a four-stage GWAS comprising 8,313 cases and 19,680 controls. Here, we show novel associations at ST6GAL1 on 3q27.3 (rs7634389, odds ratio (OR)=1.13, P=7.27 × 10(-10)), ACCS on 11p11.2 (rs2074038, OR=1.14, P=3.93 × 10(-9)) and ODF1-KLF10 on 8q22.3 (rs2033562, OR=1.13, P=1.41 × 10(-9)), validate a recently reported association at ITGAX-ITGAM on 16p11.2 (rs7190997, OR=1.22, P=2.26 × 10(-19)), and identify three independent signals within the DEFA locus (rs2738058, P=1.15 × 10(-19); rs12716641, P=9.53 × 10(-9); rs9314614, P=4.25 × 10(-9), multivariate association). The risk variants on 3q27.3 and 11p11.2 show strong association with mRNA expression levels in blood cells while allele frequencies of the risk variants within ST6GAL1, ACCS and DEFA correlate with geographical variation in IgAN prevalence. Our findings expand our understanding on IgAN genetic susceptibility and provide novel biological insights into molecular mechanisms underlying IgAN.

Imbalance of regulatory T cells to Th17 cells in IgA nephropathy.

BACKGROUND: Dysregulation of CD4 (+) T cell subsets participates in the pathogenesis of IgA nephropathy (IgAN). FoxP3 (+) regulatory T cells (Treg) and Th17 cells are two novel subsets of CD4 (+) T cells. This study aims to investigate Treg/Th17 balance in IgAN patients. METHODS: Peripheral frequencies of Th17 and Treg functional subsets - CD45RA (+) FoxP3(low) resting Treg (rTreg) and CD45RA(-)FoxP3(high) activated Treg (aTreg) were assessed in 63 adult IgAN patients. Expression of transcription factors (FoxP3 and RORγt) and related cytokines of Treg and Th17 were analysed. Renal expression of FoxP3 and IL-17A were detected by immunohistochemistry. RESULTS: Compared with normal controls, IgAN patients had decreased frequency of CD45RA(-)FoxP3(high) aTreg subset (p < 0.05), increased frequency of Th17 (p < 0.05) and decreased ratio of Treg/Th17 (p < 0.05). Frequency of aTreg subset correlated with SBP(r = - 0.57, p < 0.05), DBP (r = - 0.50, p < 0.05), eGFR (r = 0.68, p < 0.05) and 24 h proteinuria (r = - 0.58, p < 0.05). RORγtmRNA/FoxP3mRNA ratio increased in IgAN (p < 0.05). Serum IL-17A, IL-21, IL-23, IL-1ß and IL-6 elevated while IL-10 decreased in IgAN (p < 0.05), and serum IL-17A correlated with 24 h proteinuria (r = 0.35, p < 0.05). Serum TGF-ß1 wasn't different between the two groups. Renal interstitial infiltration of FoxP3 (+) mononuclear cells were observed in IgAN patients, particularly prominent in those with > 25% tubular atrophy/interstitial fibrosis. Tubular IL-17A expression was found in 34 out of 63 IgAN patients. Compared with 29 patients without IL-17A expression, these patients had lower renal function, greater proteinuria, and more severe tubulointerstitial damage. CONCLUSIONS: Imbalance of Treg/Th17 found in IgAN may play a role in disease pathogenesis and progression.