FTO-mediated m6A mRNA demethylation aggravates renal fibrosis by targeting RUNX1 and further enhancing PI3K/AKT pathway.

Chronic kidney disease (CKD) is a global health burden, with ineffective therapies leading to increasing morbidity and mortality. Renal interstitial fibrosis is a common pathway in advanced CKD, resulting in kidney function and structure deterioration. In this study, we investigate the role of FTO-mediated N6-methyladenosine (m6A) and its downstream targets in the pathogenesis of renal fibrosis. M6A modification, a prevalent mRNA internal modification, has been implicated in various organ fibrosis processes. We use a mouse model of unilateral ureteral obstruction (UUO) as an in vivo model and treated tubular epithelial cells (TECs) with transforming growth factor (TGF)-ß1 as in vitro models. Our findings revealed increased FTO expression in UUO mouse model and TGF-ß1-treated TECs. By modulating FTO expression through FTO heterozygous mutation mice (FTO+/- ) in vivo and small interfering RNA (siRNA) in vitro, we observed attenuation of UUO and TGF-ß1-induced epithelial-mesenchymal transition (EMT), as evidenced by decreased fibronectin and N-cadherin accumulation and increased E-cadherin levels. Silencing FTO significantly improved UUO and TGF-ß1-induced inflammation, apoptosis, and inhibition of autophagy. Further transcriptomic assays identified RUNX1 as a downstream candidate target of FTO. Inhibiting FTO was shown to counteract UUO/TGF-ß1-induced RUNX1 elevation in vivo and in vitro. We demonstrated that FTO signaling contributes to the elevation of RUNX1 by demethylating RUNX1 mRNA and improving its stability. Finally, we revealed that the PI3K/AKT pathway may be activated downstream of the FTO/RUNX1 axis in the pathogenesis of renal fibrosis. In conclusion, identifying small-molecule compounds that target this axis could offer promising therapeutic strategies for treating renal fibrosis.

The application of new complex indicators in the detection of urine.

BACKGROUND: Accurate diagnosis and assessment of hematuria is crucial for the early detection of chronic kidney disease(CKD). As instability of urinary RBC count (URBC) often results with clinical uncertainty, therefore new urinary indexes are demanded to improve the accuracy of diagnosis of hematuria. In this study, we aimed to investigate the benefit of applying new complex indicators based on random urine red blood cell counts confirmed in hematuric kidney diseases. METHODS: All patients enrolled underwent renal biopsy, and their clinical information was collected. Urinary and blood biomedical indexes were implemented with red blood cell counts to derive complex indicators. Patients were divided into two groups (hematuria-dominant renal histologic lesions and non-hematuria-dominant renal histologic lesions) based on their renal pathological manifestations. The target index was determined by comparing the predictive capabilities of the candidate parameters for hematuric kidney diseases. Hematuria stratification was divided into four categories based on the scale of complex indicators and distributional features. The practicality of the new complex indicators was demonstrated by fitting candidate parameters to models comprising demographic information. RESULTS: A total of 1,066 cases (678 hematuria-dominant renal histologic lesions) were included in this study, with a mean age of 44.9 ± 15 years. In differentiating hematuria-dominant renal histologic lesion from the non-hematuria-dominant renal histologic lesion, the AUC value of "The ratio of the random URBC to 24-h albumin excretion" was 0.76, higher than the standard approach of Lg (URBC) [AUC = 0.744] (95% Confidence interval (CI) 0.712 ~ 0.776). The odds ratio of hematuria-dominant renal histologic lesion (Type I) increased from Q2 (3.81, 95% CI 2.66 ~ 5.50) to Q4 (14.17, 95% CI 9.09 ~ 22.72). The predictive model, composed of stratification of new composite indexes, basic demographic characteristics, and biochemical parameters, performed best with AUC value of 0.869 (95% CI 0.856-0.905). CONCLUSION: The new urinary complex indicators improved the diagnostic accuracy of hematuria and may serve as a useful parameter for screening hematuric kidney diseases.

Association of trimethylamine N-Oxide with cardiovascular and all-cause mortality in hemodialysis patients.

BACKGROUND: Trimethylamine-N-Oxide (TMAO) is a proatherogenic and prothrombotic metabolite. Our study examined the association of plasma TMAO level with cardiovascular and all-cause mortality in hemodialysis (HD) patients. METHODS: Patients who were at least 18 years-old and received HD for at least 6 months were enrolled within 6 months. Patients with coronary heart disease, congestive heart failure, arrhythmia, or stroke within 3 months before study onset were excluded. The primary endpoints were cardiovascular and all-cause death, and the secondary endpoint was cerebrovascular death. RESULTS: We recruited 252 patients and divided them into a high-TMAO group (>4.73 µg/mL) and a low-TMAO group (≤4.73 µg/mL). The median follow-up time was 73.4 months (interquartile range: 42.9, 108). A total of 123 patients died, 39 from cardiovascular disease, 19 from cerebrovascular disease, and 65 from other causes. Kaplan-Meier analysis indicated that the high-TMAO group had a greater incidence of cardiovascular death (Log-Rank: p = 0.006) and all-cause death (Log-Rank: p < 0.001). Cox regression analysis showed that high TMAO level was significantly associated with cardiovascular and all-cause mortality. After adjustment for confounding, this association remained significant for cardiovascular mortality (TMAO as a continuous variable: HR: 1.18, 95%CI: 1.07, 1.294, p < 0.001; TMAO as a dichotomous variable: HR: 3.44, 95%CI: 1.68, 7.08, p < 0.001) and all-cause mortality (TMAO as a continuous variable: HR: 1.14, 95%CI: 1.08, 1.21, p < 0.001; TMAO as a dichotomous variable: HR: 2.54, 95%CI: 1.71, 3.76, p < 0.001). CONCLUSIONS: High plasma TMAO level is significantly and independently associated with cardiovascular and all-cause mortality in HD patients.

Preemptive renal replacement therapy in post-cardiotomy cardiogenic shock patients: a historically controlled cohort study.

BACKGROUND: The aim of the study was to evaluate whether the preemptive renal replacement therapy (RRT) might improve outcomes in post-cardiotomy cardiogenic shock (PCCS) patients. METHODS: In Period A (September 2014-April 2016), patients with PCCS received RRT, depending on conventional indications or bedside attendings. In Period B (May 2016-November 2017), the preemptive RRT strategy was implemented in all PCCS patients in our intensive care unit. The goal-directed RRT was applied for the RRT patients. The hospital mortality and renal recovery were compared between the two periods. RESULTS: A total of 155 patients (76 patients in Period A and 79 patients in Period B) were ultimately enrolled in this study. There were no significant differences in demographic characteristics and intraoperative and postoperative parameters between the two groups. The duration between surgery and RRT initiation was significantly shorter in Period B than in Period A [23 (17, 66) vs. 47 (20, 127) h, P<0.01]. The hospital mortality in Period B was significantly lower than that in Period A (38.0% vs. 59.2%, P<0.01). There were fewer patients with no renal recovery in Period B (4.1% vs. 19.4%, P=0.026). Patients in Period B displayed a significantly shorter time to completely renal recovery (12±15 vs. 25±15 d, P<0.05). CONCLUSIONS: Among PCCS patients, preemptive RRT compared with conventional initiation of RRT reduced mortality in hospital and also led to faster and more frequent recovery of renal function. Our preliminary study supposed that preemptive initiation of RRT might be an effective approach to PCCS with acute kidney injury (AKI).

Self-Care Behavior of Hemodialysis Patients With Arteriovenous Fistula in China: A Multicenter, Cross-Sectional Study.

Improving the level of arteriovenous fistula (AVF) self-care behavior by people receiving hemodialysis is an effective way to reduce the occurrence of complications and mortality. The aim of this study was to assess the self-care behavior of Chinese patients undergoing hemodialysis with arteriovenous fistula. The assessment of self-care behaviors with arteriovenous fistula in hemodialysis (ASBHD-AVF, Portuguese version) was translated into Chinese using Brislin's translation model. The content validity was evaluated by six experts. Then we involved 301 hemodialysis patients with AVF to explore the construct validity of the Chinese version of ASBHD-AVF. Ultimately 216 patients from eight dialysis centers of general hospitals in China were recruited to evaluate the patients' self-care behavior about AVF. Measures included demographic questionnaire, and the Chinese ASBHD-AVF. The Chinese ASBHD-AVF that included 12 items has a good internal consistency (α = 0.865) and content validity (CVI = 0.979). Principal component analysis generated two factors which explained 53.525% of the total variance. About 69.9% of hemodialysis patients' AVF self-care behavior were at a low or moderate level. The level of self-care behavior and knowledge need to be improved. Nurses should give specific guidance according to the patients' own characteristics and different influence factors, in order to improve the recipients' self-care behavior.

Endoplasmic reticulum stress associated apoptosis as a novel mechanism in indoxyl sulfate­induced cardiomyocyte toxicity.

Indoxyl sulfate (IS), a typical uremic toxin, is of great importance in the development of chronic kidney disease. In addition to its nephrotoxicity, previous studies have provided increasing evidence for its cardiovascular toxicity. The mechanism underlying IS­induced cardiovascular toxicity has been elusive to date. The present study aimed to evaluate whether IS treatment could induce apoptosis of H9C2 cells, and used the endoplasmic reticulum (ER) stress­modulator 4­phenylbutyric acid (4­PBA) to evaluate whether IS­induced apoptosis is indeed associated with ERS. To evaluate whether IS induces apoptosis in H9C2 cardiomyocytes, cells were exposed to increasing concentrations of IS (500, 1,000, and 2,000 µM) for 24 h, and apoptosis was detected by flow cytometry. To determine whether IS­induced apoptosis is associated with ERS, cells were divided into 4 groups: control group, PBA group, IS group and PBA+IS group. IS dose­dependently induced apoptosis, and increased the expression of ER chaperones in H9C2 cells. Additionally, 4­PBA treatment decreased IS­induced apoptosis, and reduced ERS­associated protein expression induced by IS. Therefore, the mechanism may be associated with the CCAAT­enhancer­binding protein homologous protein and c­Jun N­terminal kinase signaling pathways.

Reversible preoperative renal dysfunction does not add to the risk of postoperative acute kidney injury after cardiac valve surgery.

OBJECTIVE: To evaluate the impact of the renal dysfunction (RD) type and change of postoperative cardiac function on the risk of developing acute kidney injury (AKI) in patients who underwent cardiac valve surgery. METHOD: Reversible renal dysfunction (RRD) was defined as preoperative RD in patients who had not been initially diagnosed with chronic kidney disease (CKD). Cardiac function improvement (CFI) was defined as postoperative left ventricular ejection function - preoperative left ventricular ejection function (ΔEF) >0%, and cardiac function not improved (CFNI) as ΔEF ≤0%. RESULTS: Of the 4,805 (94%) cardiac valve surgery patients, 301 (6%) were RD cases. The AKI incidence in the RRD group (n=252) was significantly lower than in the CKD group (n=49) (36.5% vs 63.3%, P=0.018). The AKI and renal replacement therapy incidences in the CFI group (n=174) were significantly lower than in the CFNI group (n=127) (33.9% vs 50.4%, P=0.004; 6.3% vs 13.4%, P=0.037). After adjustment for age, gender, and other confounding factors, CKD and CKD + CFNI were identified as independent risk factors for AKI in all patients after cardiac valve surgery. Multivariate logistic regression analysis showed that the risk factors for postoperative AKI in preoperative RD patients were age, gender (male), hypertension, diabetes, chronic heart failure, cardiopulmonary bypass time (every 1 min added), and intraoperative hypotension, while CFI after surgery could reduce the risk. CONCLUSION: For cardiac valve surgery patients, preoperative CKD was an independent risk factor for postoperative AKI, but RRD did not add to the risk. Improved postoperative cardiac function can significantly reduce the risk of postoperative AKI.

High-dose versus low-dose haemofiltration for the treatment of critically ill patients with acute kidney injury: an updated systematic review and meta-analysis.

OBJECTIVE: The purpose of this study was to perform a systematic review and meta-analysis to evaluate the effect of high-dose versus low-dose haemofiltration on the survival of critically ill patients with acute kidney injury (AKI). We hypothesised that high-dose treatments are not associated with a higher risk of mortality. DESIGN: Meta-analysis. SETTING: Randomised controlled trials and two-arm prospective and retrospective studies were included. PARTICIPANTS: Critically ill patients with AKI. INTERVENTIONS: Continuous renal replacement therapy. PRIMARY AND SECONDARY OUTCOME MEASURES: Primary outcomes: 90-day mortality, intensive care unit (ICU) mortality, hospital mortality; secondary outcomes: length of ICU and hospital stay. RESULT: Eight studies including 2970 patients were included in the analysis. Pooled results showed no significant difference in the 90-mortality rate between patients treated with high-dose or low-dose haemofiltration (pooled OR=0.90, 95% CI 0.73 to 1.11, p=0.32). Findings were similar for ICU (pooled OR=1.12, 95% CI 0.94 to 1.34, p=0.21) and hospital mortality (pooled OR=1.03, 95% CI 0.81 to 1.30, p=0.84). Length of ICU and hospital stay were similar between high-dose and low-dose groups. Pooled results are not overly influenced by any one study, different cut-off points of prescribed dose or different cut-off points of delivered dose. Meta-regression analysis indicated that the results were not affected by the percentage of patients with sepsis or septic shock. CONCLUSION: High-dose and low-dose haemofiltration produce similar outcomes with respect to mortality and length of ICU and hospital stay in critically ill patients with AKI.This study was not registered at the time the data were collected and analysed. It has since been registered on 17 February 2017 at http://www.researchregistry.com/, registration number: reviewregistry211.

Significance of perioperative goal-directed hemodynamic approach in preventing postoperative complications in patients after cardiac surgery: a meta-analysis and systematic review.

PURPOSE: Goal-directed hemodynamic therapy (GDT) is used to prevent hypoperfusion resulting from surgery. The objective of this study was to analyze the efficacy and importance of perioperative GDT. METHODS: PUBMED, MEDLINE, CENTRAL, and Google Scholar databases were searched until 17 June 2016 using the search terms: cardiac output, cardiac surgical procedures, hemodynamics, goal-directed therapy, and intraoperative. Randomized-controlled trials with pre-emptive hemodynamic intervention for cardiac surgical population versus standard hemodynamic therapy were included. RESULTS: Nine studies were included with a total of 1148 patients. The overall analysis revealed no significant difference in the all-cause mortality (pooled peto OR =0.58, 95%CI =0.27-1.525, p = 0.164), duration of mechanical ventilation (pooled difference in mean= -1.48, 95%CI= -3.24 to 0.28, p = 0.099), or length of intensive care unit (ICU) stay (pooled difference in mean= -9.10, 95%CI= -20.14 to 1.93, p = 0.106) between patients in the GDT and control groups. Patients in the GDP group were associated with shorter hospital stay than those in the control group (pooled difference in mean= -1.52, 95%CI= -2.31 to -0.73, p < 0.001). CONCLUSION: GDT reduces the length of hospital stay compared with the standard of care. Further studies are necessary to continually assess the benefit of GDT following major surgery. Key Messages The results of this analysis revealed no significant difference between cardiac surgery patients receiving goal-directed hemodynamic therapy (GDT) or conventional fluid therapy in terms of the all-cause mortality, duration of mechanical intervention, and length of ICU-stay. The length of hospital stay was significantly reduced in patients treated with GDT compare to conventional fluid therapy. GDT may have limited benefit in reducing mortality; however, the association to shorter length of hospital stay may suggest that better hemodynamic balance can facilitate postoperative recovery.

Hopf Bifurcation of an Epidemic Model with Delay.

A spatiotemporal epidemic model with nonlinear incidence rate and Neumann boundary conditions is investigated. On the basis of the analysis of eigenvalues of the eigenpolynomial, we derive the conditions of the existence of Hopf bifurcation in one dimension space. By utilizing the normal form theory and the center manifold theorem of partial functional differential equations (PFDs), the properties of bifurcating periodic solutions are analyzed. Moreover, according to numerical simulations, it is found that the periodic solutions can emerge in delayed epidemic model with spatial diffusion, which is consistent with our theoretical results. The obtained results may provide a new viewpoint for the recurrent outbreak of disease.

Lymphocyte depletion and subset alteration correlate to renal function in chronic kidney disease patients.

BACKGROUND: It is widely accepted that chronic renal failure is associated with severe alterations of immune system. However, few studies looked into the immune alteration in earlier stage of chronic kidney disease (CKD) patients. To characterize immune defect in CKD patients, we performed lymphocyte subset analysis and explored its relationship to renal function in this population. METHODS: 472 CKD patients were enrolled in this study. Lymphocyte subsets (CD19(+), CD3(+), CD3(+)CD4(+), CD3(+)CD8(+), CD56(+)CD16(+)) were determined by flow cytometry. Clinical and laboratory data were collected. Patterns of immune cells in different stages of CKD were compared. Multivariate linear regression was used to evaluate the relationship between lymphocyte subset group and renal function. Correlation analysis was used to assess the relationship between lymphocyte subset and other clinical and laboratory data. RESULTS: Decreased lymphocyte counts occurred long before the end stage of renal disease. Increased NK cell percentage was negatively related to estimated glomerular filtration rate (eGFR) (r = -0.259, p < 0.001) while B cell percentage was positively related to eGFR (r = 0.249, p < 0.001). Further multivariate linear regression showed increased B cell percentage (ß = 16.470, 95%CI [1.018-31.922], p = 0.037) and decreased NK cell percentage (ß = -10.659, 95%CI [-20.063 to -1.254], p = 0.026) were independently correlated with higher eGFR, respectively. Patients with lower NK cell percentage and higher B cell percentage tended to have the best renal function. CONCLUSIONS: Lymphocyte depletion and subset alteration occurred during the progress of CKD. Further studies are needed to clarify the role of immune system in CKD and to expand our knowledge about the effect of uremia on the structure and function of immune system.

Delayed ischaemic preconditioning in the presence of galectin-9 protects against renal ischaemic injury through a regulatory T-cell dependent mechanism.

AIM: Renal ischaemia/reperfusion injury (IRI) is a complication of major surgeries. Regulatory T cells (Tregs) can suppress immunologic damage in the renal IR. Previous studies indicated that delayed ischaemic preconditioning (IPC) partially attenuates IR by inducing Treg expansion. Galectin-9 also attenuates inflammation-related organ injury by expanding Tregs, but it was not used in renal IR yet. Our aim was to test whether IPC combined with galectin-9 has an increased renoprotective effect. METHODS: Mice were divided into five treatment groups (n = 6 per group): (i) IR group: renal ischaemia/reperfusion group; (ii) IPC-IR group: IPC followed by renal IR; (iii) IPC-Gal9-IR group: Gal-9 injections during the time between IPC and IR; (iv) IPC-Gal9-PC61-IR group: anti-CD25 antibody administration apart from IPC, Gal-9 and IR; (v) sham-sham group. We assessed the renal function, histopathological scores, and percentages of Tregs and interferon-γ (IFN-γ) cells in peripheral bood, spleen, and kidney and compared these values among the different groups. RESULTS: Serum creatinine measured was significantly lower after IPC and even lower in combination with Gal-9 injection. The histopathological scores for tubulo-interstitial injury were decreased following IPC and markedly lower after the addition of Gal-9. The number of kidney infiltrating neutrophils and IFN-γ secreting CD4+ T cells was diminished in the IPC/Gal9 combination group, while the percentage of Treg cells in the peripheral blood, spleen, and kidney of animals from the IPC-Gal9-IR group was also markedly increased. CONCLUSION: The renoprotective effect of delayed IPC combined with galectin-9 was superior to IPC alone, through a mechanism related to expansion of regulatory T cells.

Risk Factors for Long-Term Mortality and Progressive Chronic Kidney Disease Associated With Acute Kidney Injury After Cardiac Surgery.

The aim of the study was to evaluate risk factors for long-term mortality and progressive chronic kidney disease (CKD) after cardiac surgery in patients with normal preoperative renal function and postoperative acute kidney injury (AKI). From April 2009 to December 2012, we prospectively enrolled 3245 cardiac surgery patients of our hospital. The primary endpoints included survival rates and the secondary endpoint was the incidence of progressive chronic kidney disease (CKD) in a follow-up period of 2 years. Acute kidney injury was staged by KDIGO classification. Progressive CKD was defined as GFR ≤ 30 mL/min/1.73 m or end-stage renal disease (ESRD) (starting renal replacement therapy or renal transplantation).The AKI incidence was 39.9% (n = 1295). The 1 and 2 year overall survival (OS) rates of AKI patients were significantly lower than that for non-AKI patients (85.9% and 82.3% vs 98.1% and 93.7%, P < 0.001), even after complete recovery of renal function during 2 years after intervention (P < 0.001). The 2-year overall survival (OS) rates of patients with AKI stage 1, 2, and 3 were 89.9%, 78.6%, and 61.4% (P < 0.001), respectively. Multivariate Cox regression analysis of factors for 2-year survival rates revealed that besides age (P < 0.001), chronic cardiac failure (P < 0.001), diabetes (P < 0.001), cardiopulmonary bypass time (P < 0.01), and length of intensive care unit (ICU) stay (P = 0.004), AKI was a significant risk factor for reducing 2-year survival rates even after complete recovery of renal function (P < 0.001). The accumulated progressive CKD prevalence was significantly higher in AKI than in non-AKI patients (6.8% vs 0.2%, P < 0.001) in the 2 years after surgery. Even with complete recovery of renal function at discharge, AKI was still a risk factor for accumulated progressive CKD (RR 1.92, 95% CI 1.37-2.69).The 2-year mortality and progressive CKD incidence even after complete recovery of renal function were significantly increased in cardiac surgery patients with postoperative AKI.

[Multi-center randomized control study on the effects of syndrome differentiated traditional Chinese medicine therapy on CKD 1-2 with chronic nephritis proteinuria].

OBJECTIVE: To determine the effects of Syndrome Differentiated Chinese Medicine (TCM) Therapy on (CKD) 1-2 stage chronic kidney disease with proteinuria. METHODS: A prospective randomized control study was undertaken in 11 centers. A total of 396 chronic nephritis patients were divided into a treatment group (n=297) and a control group (n=99). Their TCM syndrome was classified as "Qi and Yin Deficiency of spleen and kidney" or "Qi and Yang Deficiency of spleen and kidney", with accompanying syndromes showing as "water and dampness", "damp-heat", and "blood stasis". Patients in the treatment group took a dose of Chinese medicine daily in response to their syndromes, while the controls took 50 mg/d losartan. The course of treatment was 24 weeks. Changes of 24-hour urinary protein excretion and glomerular filtration rate (eGFR) before and after treatments (4, 8, 12, 16, 20, 24 weeks), as well as clinical efficacy (after 4, 16, 24 weeks treatments) were measured. RESULTS: 361 patients were included in the final program participants comply analysis (PPS). Patients in the treatment group showed gradual decreased 24-hour urinary protein excretion, whereas the controls remained unchanged. Significant differences in 24-hour urinary protein excretion appeared between the experimental and control group at week 20 and 24 (P<0.05). eGFR decreased in all of the patients after treatments (P=0.0014). At three follow-up points, patients in the treatment group had higher eGFR than the controls, but without statistical significance (P>0.05). Significant differences in clinical remission rate, marked effect rate and total effective rate were observed between the treatment and control groups at week 24 (P<0.001). CONCLUSION: Syndrome differentiated TCM therapy can reduce the level of proteinuria in CKD 1-2 nephritis patients, promoting clinical effectiveness and protecting renal functions.

Association of indoxyl sulfate with heart failure among patients on hemodialysis.

BACKGROUND AND OBJECTIVES: Indoxyl sulfate, a protein-bound uremic toxin, may be associated with cardiovascular events and mortality in patients with CKD. This study aimed to investigate the relationship between indoxyl sulfate and heart failure in patients on hemodialysis. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: Patients on hemodialysis for >6 months were enrolled within 6 months. Patients with congestive heart failure, angina pectoris, acute myocardial infarction, cerebral infarction, or cerebral hemorrhage within 3 months before the study or those <18 years old were excluded. The primary end point was first heart failure event during follow-up. RESULTS: In total, 258 patients (145 men) with a mean age of 57.0 ± 14.6 years old were enrolled. Median plasma indoxyl sulfate level was used to categorize patients into two groups: the low-indoxyl sulfate group (indoxyl sulfate ≤ 2.35 µg/ml) and the high-indoxyl sulfate group (indoxyl sulfate >32.35 µg/ml). Then, patients were prospectively followed up for a median of 48.0 (interquartile range: 33.5-48.0) months. During follow-up, 68 patients experienced episodes of first heart failure. Kaplan-Meier analysis revealed the incidence of first heart failure event in the high-indoxyl sulfate group was significantly higher than in the low-indoxyl sulfate group (log rank P<0.001). Cox regression analysis showed indoxyl sulfate was significantly associated with first heart failure event (indoxyl sulfate as the continuous variable: hazard ratio, 1.02; 95% confidence interval [95% CI], 1.01 to 1.03; P=0.001; indoxyl sulfate as the dichotomous variable: hazard ratio, 3.49; 95% CI, 1.97 to 6.20; P<0.001). After adjustment for other confounding factors, the results remained significant (indoxyl sulfate as the continuous variable: hazard ratio, 1.04; 95% CI, 1.02 to 1.06; P<0.001; indoxyl sulfate as the dichotomous variable: hazard ratio, 5.31; 95% CI, 2.43 to 11.58; P<0.001). CONCLUSIONS: Plasma indoxyl sulfate was associated with first heart failure event in patients on hemodialysis. Whether indoxyl sulfate is only a biomarker or involved in the pathogenesis of heart failure in hemodialysis warrants additional study.

Inappropriately elevated endothelin-1 plays a role in the pathogenesis of intradialytic hypertension.

The aim of this study is to investigate the effects of endogenous vasoactive substances on the occurrence of intradialytic hypertension (IDH) in patients during maintenance hemodialysis. Thirty-four maintenance hemodialysis patients were enrolled in this trial, and 17 of them were diagnosed with IDH (defined as an increase in blood pressure of at least 10 mmHg during or immediately after a hemodialysis session), while 17 age-matched and sex-matched controls without IDH were selected for a retrospective comparison. We collected patients' blood samples before and after a dialysis session and measured the plasma levels of N-terminal fragment brain natriuretic peptide, renin, angiotensin-II, aldosterone (ALD), angiotensin-converting enzyme (ACE), endothelin-1 (ET-1), nitric oxide (NO), norepinephrine (NOR), and adrenomedullin. The post-dialysis serum ET-1 concentrations were significantly higher (4.09 ± 2.06 vs. 2.75 ± 1.34 pg/mL, P < 0.05), while the post-dialysis ratio of NO to ET-1 was lower (17.79 ± 5.65 vs. 24.78 ± 12.04, P < 0.05) in IDH patients compared with the control group. Post-dialysis ALD and NOR values were significantly lower (P < 0.01) and ACE levels were significantly higher (P < 0.01) than the pre-dialysis concentrations only in the control and not in the IDH group. All other measured factors did not differ significantly between the groups and between pre-dialysis and post-dialysis determinations. Compared with blood angiotensin-II, ALD, ACE, NOR, adrenomedullin, N-terminal fragment brain natriuretic peptide, and NO status, inappropriately elevated ET-1 plasma concentrations may play a predominant role in the pathogenesis of IDH.

A novel contrast-induced acute kidney injury model based on the 5/6-nephrectomy rat and nephrotoxicological evaluation of iohexol and iodixanol in vivo.

Contrast-induced acute kidney injury (CI-AKI) is a serious complication in patients after administration of iodinated contrast media. Proper animal models of CI-AKI can help understand the mechanisms involved and prevent the disorder. We used the 5/6-nephrectomized (NE) rat to develop a CI-AKI model and to evaluate differences in the toxic effects on the kidney between iohexol and iodixanol. We found that six weeks after ablative surgery was the preferred time to induce CI-AKI. We compared multiple pretreatment plans and found that dehydration for 48 hours before iodixanol (320, 10 mL/kg) administration was optimal to induce CI-AKI in the 5/6 NE rats. Compared with iodixanol, iohexol induced a significantly greater reduction in renal function, severe renal tissue damage, intrarenal hypoxia, and apoptotic tubular cells. Iohexol and iodixanol resulted in similarly marked increases in levels of inflammation and oxidative stress. In summary, the 5/6 NE rat combined with dehydration for 48 hours is a useful pretreatment to establish a novel and reliable CI-AKI model. Iohexol induced more severe CI-AKI than iodixanol in this model.

Rapamycin reduces renal hypoxia, interstitial inflammation and fibrosis in a rat model of unilateral ureteral obstruction.

PURPOSE: The purpose of this study was to explore effects of rapamycin on renal hypoxia, interstitial inflammation and fibrosis, and the expression of transforming growth factor ß1 (TGF-ß1), vascular endothelial growth factor (VEGF), Flk-1 and Flt-1 in a rat model of unilateral ureteral obstruction (UUO). METHODS: Male Sprague-Dawley rats (n=36) were randomly divided into three groups (n=12 per group): sham surgery, UUO and UUO plus rapamycin (0.2 mg/kg/d). Serum creatinine (Scr), blood urea nitrogen, uric acid, triglycerides, cholesterol and 24-h urine protein levels were measured. The extent of interstitial fibrosis was determined by Masson's trichrome staining. ED-1 positive macrophages, type III collagen, hypoxia, TGF-1, VEGF, Flk-1, and Flt-1 mRNA and protein expressions were detected using immunohistochemical staining, real-time PCR and Western blot. RESULTS: UUO induced an elevation in Scr, renal hypoxia, inflammation, interstitial fibrosis, TGF-ß1, VEGF, Flk-1, and Flt-1 mRNA and protein expression levels (P < 0.05). Rapamycin alleviated the UUO-induced renal hypoxia, infiltration of inflammatory cells and tubulointerstitial fibrosis (at days 3 and 7). Rapamycin also down-regulated the UUO-induced elevated expression levels of TGF-ß1 and Flt-1 mRNA and protein (P < 0.05). Rapamycin decreased VEGF mRNA and protein expression at day 3, and increased Flk-1 mRNA and protein expression at day 7, compared with the UUO group (P < 0.05). CONCLUSION: Rapamycin shows beneficial effects by reducing UUO-induced renal hypoxia, inflammation and tubulointerstitial fibrosis.

Efficacy and safety of Abelmoschus manihot for primary glomerular disease: a prospective, multicenter randomized controlled clinical trial.

BACKGROUND: Abelmoschus manihot, a single medicament of traditional Chinese medicine, has been widely used to treat kidney disease. This is the first randomized controlled clinical trial to assess its efficacy and safety in patients with primary glomerular disease. STUDY DESIGN: Prospective, open-label, multicenter, randomized, controlled, clinical trial. SETTING & PARTICIPANTS: From May 2010 to October 2011, a total of 417 patients with biopsy-proven primary glomerular disease from 26 hospitals participated in the study. INTERVENTIONS: A manihot in the form of a huangkui capsule, 2.5 g, 3 times per day; losartan potassium, 50mg/d; or combined treatment, a huangkui capsule at 2.5 g 3 times per day, was combined with losartan potassium, 50mg/d. The duration of intervention was 24 weeks. OUTCOMES & MEASUREMENTS: The primary outcome was change in 24-hour proteinuria from baseline after treatment. Change in estimated glomerular filtration rate (eGFR) from baseline after treatment was a secondary outcome. The 24-hour proteinuria was measured every 4 weeks and eGFR was measured at 0, 4, 12, and 24 weeks. RESULTS: Mean baseline urine protein excretion was 1,045, 1,084, and 1,073 mg/d in the A manihot, losartan, and combined groups, respectively, and mean eGFR was 108, 106, and 106 mL/min/1.73 m2, respectively. After 24 weeks of treatment, mean changes in proteinuria were protein excretion of -508, -376, and -545 mg/d, respectively (P=0.003 for A manihot vs losartan and P<0.001 for the combined treatment vs losartan). Mean eGFR did not change significantly. The incidence of adverse reactions was not different among the 3 groups (P>0.05), and there were no severe adverse events in any group. LIMITATIONS: Results cannot be generalized to those with nephrotic syndrome or reduced eGFR. CONCLUSIONS: A manihot is a promising therapy for patients with primary kidney disease (chronic kidney disease stages 1-2) with moderate proteinuria.

Efficacy and safety of Changfu peritoneal dialysis solution: a multi-center prospective randomized controlled trial.

BACKGROUND: A multi-center large scale study is needed to confirm the efficacy and safety of domestic peritoneal dialysis (PD) solutions. Some researchers believe that 6 L/d is enough for adequate dialysis, but there is no multi-center prospective study on Chinese population to confirm this. In this study, we evaluated the efficacy and safety of domestic PD solution (Changfu) and its difference between 6 L and 8 L dosage. METHODS: Adult PD patients who had taken PD therapy for at least one month were selected and divided into four groups according to two dialysis solution brands and two dialysis dosages, i.e., 6 L dose with Changfu dialysis solution, 6 L dose with Baxter dialysis solution, 8 L dose with Changfu dialysis solution, and 8 L dose with Baxter dialysis solution. After 48 weeks, the changes of primary and secondary efficacy indices were compared between different types and different dosages. We also analyzed the changes of safety indices. RESULTS: Changes of Kt/V from baseline to 48 weeks between Changfu and Baxter showed no statistical differences; so did those of creatinine clearance rate (Ccr). Normalized protein catabolic rate (nPCR) from baseline to 48 weeks between Changfu and Baxter showed no statistical differences; so did those of net ultrafiltration volume (nUF) and estimated glomerular filtration rate (eGFR). Changes of nPCR from baseline to 48 weeks between 6 L and 8 L showed no statistical differences; so did those of nUF and eGFR. The decline of Kt/V from baseline to 48 weeks in 6 L group was more than that in 8 L group. Change of Ccr was similar. During the 48-week period, the mean Kt/V was above 1.7/w, and mean Ccr was above 50 L×1.73 m(-2)×w(-1). More adverse events were found in Changfu group before Changfu Corporation commenced technology optimization, and the statistical differences disappeared after that. CONCLUSIONS: The domestic PD solution (Changfu) was proven to be as effective as Baxter dialysis solution. During 48-week period, a dosage of 6 L/d was enough for these patients to reach adequate PD. Clinical study promotes technological optimization, further helps to improve the safety indices of the medical products.