Search

To investigate the association of clinical and histological characteristics and the development of ESRD in T2DM patients with renal involvement. We conducted a retrospective analysis of clinical and pathologic data from T2DM patients who underwent renal biopsy (n = 120). The mean age, duration of diabetes, and eGFR were 50.9 ± 11.2 years, 92.8 ± 41.3 months, 55.1 ± 42.3 mL/min/1.73 m2, respectively. Among these patients, 57 (47.5%) were diagnosed with diabetic nephropathy (DN), and 63 (52.5%) with non-diabetic renal disease (NDRD). The most common subtype of NDRD is membranous nephropathy. Compared with the NDRD group, the DN group had a longer duration of diabetes, worse renal function, and a higher proportion of diabetic retinopathy. Kaplan–Meier analysis showed that the 5-year renal survival rate of the DN group was only 41%, whereas that of the NDRD group was 84%. ESRD was defined as eGFR below 15 mL/min/1.73 m2. After multivariate adjustment, the risk of ESRD in DN patients was 3.81 times higher than that in NDRD patients. According to Glomerular Class, the 5-year renal survival rate of type IIA, IIB, III, and IV in the DN group was 88, 56, 28, and 15%, respectively. Kaplan–Meier analysis showed that there was a significant difference in renal survival among different glomerular classes or different interstitial fibrosis and tubular atrophy (IFTA) scores. But Cox proportional hazards analysis indicated that only IFTA score (HR 2.75, 95% CI 1.37–5.51, P = 0.001), but not the glomerular class (HR 1.21, 95% CI 0.73–2.00, P = 0.465), could predict renal outcome when adjusting for multivariate. The prognosis of DN patients is significantly worse than that of NDRD patients. Compared with glomerular lesions, tubulointerstitial lesions were associated with higher risk for renal death in DN patients.

Fatty acid oxidation (FAO) dysfunction is one of the important mechanisms of renal fibrosis. Sirtuin 3 (Sirt3) has been confirmed to alleviate acute kidney injury (AKI) by improving mitochondrial function and participate in the regulation of FAO in other disease models. However, it is not clear whether Sirt3 is involved in regulating FAO to improve the prognosis of AKI induced by cisplatin. Here, using a murine model of cisplatin‐induced AKI, we revealed that there were significantly FAO dysfunction and extensive lipid deposition in the mice with AKI. Metabolomics analysis suggested reprogrammed energy metabolism and decreased ATP production. In addition, fatty acid deposition can increase reactive oxygen species (ROS) production and induce apoptosis. Our data suggested that Sirt3 deletion aggravated FAO dysfunction, resulting in increased apoptosis of kidney tissues and aggravated renal injury. The activation of Sirt3 by honokiol could improve FAO and renal function and reduced fatty acid deposition in wide‐type mice, but not Sirt3‐defective mice. We concluded that Sirt3 may regulate FAO by deacetylating liver kinase B1 and activating AMP‐activated protein kinase. Also, the activation of Sirt3 by honokiol increased ATP production as well as reduced ROS and lipid peroxidation through improving mitochondrial function. Collectively, these results provide new evidence that Sirt3 is protective against AKI. Enhancing Sirt3 to improve FAO may be a potential strategy to prevent kidney injury in the future.

Background Elevated serum uric acid (SUA) is associated with increased cardiovascular (CV) and all-cause mortality risk in the general population, but the impact of UA on mortality in hemodialysis patients is still controversial. The aim of the study was to explore the relationship between SUA and all-cause mortality and CV mortality in hemodialysis patients. Methods This retrospective, observational cohort study included 210 HD patients with a mean age of 56.6 ± 16.6 years. All demographic and laboratory data were recorded at baseline. The Kaplan–Meier method and Cox proportional hazard regression model were used to examine the association between SUA and all-cause mortality and CV mortality in HD patients. Results With 420 µmol/L (20th percentile) and 644 µmol/L (80th percentile) as the boundary points, the patients were divided into three groups. After a median follow-up of 49.8 months, 68 (32.4%) all-cause deaths and 34 (16.2%) CV deaths were recorded. The Kaplan–Meier method showed that with a decrease in SUA, all-cause mortality (log rank χ2 = 15.61, p = .000), and CV mortality (log rank χ2=14.28, p = .000) increased. Each 100 µmol/L increase in SUA was associated with lower all-cause mortality with an hazard ratio (HR) of 0.792 (0.645–0.972) and lower CV mortality with an HR of 0.683 (0.505–0.924) after adjusting for age, sex, and complications. Compared to the lowest quartile, all-cause mortality [HR 0.351(0.132–0.934), p = .036] and CV mortality [HR 0.112 (0.014–0.925), p = .042] were lower in the highest SUA quartile. Conclusion A lower SUA level in HD patients was associated with a higher risk of all-cause mortality and CV mortality. Moreover, higher SUA concentrations may be cardioprotective in HD patients.

Aim: To identify the alterations of N6-methyladenosine (m6A) RNA profiles in cisplatin-induced acute kidney injury (Cis-AKI) in mice.Materials and Methods: The total level of m6A and the expression of methyltransferases and demethylases in the kidneys were measured. The profiles of methylated RNAs were determined by the microarray method. Bioinformatics analysis was performed to predict the functions.Results: Global m6A levels were increased after cisplatin treatment, accompanied by the alterations of Mettl3, Mettl14, Wtap, Fto, and Alkbh5. A total of 618 mRNAs and 98 lncRNAs were significantly differentially methylated in response to cisplatin treatment. Bioinformatics analysis indicated that the methylated mRNAs predominantly acted on the metabolic process.Conclusion: M6A epitranscriptome might be significantly altered in Cis-AKI, which is potentially implicated in the development of nephrotoxicity.

The relationship between resting pulse rate (PR) and the occurrence of hypertension and cardiovascular (CV) mortality has been described in the general population. Few studies have examined the relationship between ambulatory PR, ambulatory blood pressure (BP), and target organ damage (TOD) in patients with chronic kidney disease (CKD). A total of 1509 patients with CKD were recruited in our hospital. Ambulatory blood pressure monitoring (ABPM) over a 24‐hours period was performed and referenced with clinical data in this cross‐sectional study. TOD was measured by estimated glomerular filtration rate (eGFR), left ventricular hypertrophy (LVH), and carotid intima‐media thickness (cIMT). Univariate and multivariate analyses were used to evaluate the relationship between PR, BP, and TOD. The percentage of male patients was 58.3% with a mean age of 44.6 ± 16.2 years. Nocturnal PR rather than 24‐hours PR or daytime PR was an independent risk factor for clinical hypertension, 24‐hours hypertension, BP dipper state, poor renal function, and LVH. In addition, the authors found that nighttime PR >74 beats/min (bpm) group was independently associated with clinical hypertension, 24‐hours hypertension, day and night hypertension, nondipping BP, lower eGFR, and LVH when compared with nighttime PR 74 bpm group was performed. Multivariate analyses indicated nighttime PR >74 bpm remained independently associated with clinical hypertension, daytime and nighttime hypertension, and LVH. An increased nocturnal PR is associated with TOD, higher BP, and nondipping BP in patients with CKD.

Background Heterozygous mutations in the inverted formin 2 (INF2) gene are related to secondary focal segmental glomerulosclerosis (FSGS), a rare secondary disease associated with rapidly progressive renal failure. Case presentation We report a patient with familial autosomal INF2 mutation manifesting nephritic syndromes and elevated serum creatinine levels. Mutational analysis revealed an autosomal dominant (AD) inheritance pattern and a mutation in exon 4 (p.Arg214Cys) of INF2 as the likely cause, which has not been previously described in an Asian family. The patient progressed to end-stage renal disease (ESRD) and received hemodialysis. His mother had undergone renal transplant 3 years earlier, and his grandmother had carried the p.Arg214Cys mutation for more than 80 years without any sign of renal dysfunction. Conclusions This is the first report to identify an association between a familial autosomal dominant INF2 p.Arg214Cys mutation and rapidly progressive renal disease in an Asian family. INF2 mutation analysis should not be restricted to individuals without family history of FSGS, rather it should also be performed on individuals for whom drug-based therapies are not effective. In this case, kidney transplant is an effective alternative.

Pulmonary hypertension is common in chronic kidney disease (CKD) patients. However, the prognostic value of pulmonary hypertension in Chinese predialytic CKD patients is rarely reported. We evaluated the relevant factors and prognostic value of pulmonary hypertension in CKD patients. This retrospective cohort study enrolled 1092 predialytic patients from The Third Affiliated Hospital of Sun Yat-Sen University from May 1st, 2011, to December 31st, 2016. Data of interest were retrieved from electronic medical records. Pulmonary hypertension was defined as pulmonary arterial systolic pressure (PASP) ≥ 35 mmHg by echocardiology. All participants were followed from the date of the first echocardiography examination. The primary endpoints were all-cause mortality and cardiovascular mortality. The secondary endpoint was end-stage renal disease (ESRD) defined as starting renal replacement therapy. The prevalence of pulmonary hypertension was 15.9% in the study population. For CKD stage 1, 2, 3a, 3b, 4 and 5, the prevalence was 6.0%, 9.6%, 17.2%, 13.3%, 20.7% and 26.6%, respectively. Older age, lower left ventricular ejection fraction, anemia and higher pulse pressure were independently associated with pulmonary hypertension in CKD patients. In multivariate Cox regression analysis, pulmonary hypertension was the independent risk factor for cardiovascular mortality, but not of all-cause mortality and ESRD. Pulmonary hypertension is not rare in early CKD patients. Patients with older age, anemia, higher pulse pressure and compromised heart function were more likely to comorbid pulmonary hypertension. Pulmonary hypertension maybe a sign of worse cardiovascular outcome in CKD patients.

The authors aimed to investigate the epidemiology of morning blood pressure (BP) surge (MBPS) in chronic kidney disease (CKD) patients, and the interaction effect between MBPS and dipping status for target organ damage (TOD). A total of 823 non‐dialysis CKD patients were enrolled in this cross‐sectional study. Subjects were grouped according to their systolic BP morning surge and dipping status, assessed by 24‐hour ambulatory BP monitoring. Patients with elevated MBPS had the highest quartile of MBPS (≥26.89 mm Hg). Non‐dipping pattern was defined as a decline in the nocturnal systolic BP of .05). There was a statistically significant association between MBPS and the non‐dipping pattern (OR 0.17, 95% CI 0.12‐0.25; OR 0.92, 95% CI 0.91‐0.93). Multiple linear regression analyses showed that excessive MBPS is an independent risk factor for poor renal function, independent of a non‐dipping pattern, and BP level, whereas the non‐dipping pattern was an important risk factor for left ventricular hypertrophy. Special attention should be paid to synchronous control of MBPS and nocturnal BP in CKD patients in clinical practice.

Background/Aims: Previously we have shown that activation of the nuclear factor (erythroid-derived 2)-like 2 (Nrf2)-antioxidant response element (ARE) attenuated hyperglycemia-induced damage in podocytes, but the molecular mechanism remains unknown. Methods: Tert-butylhydroquinone (t-BHQ) and small interfering RNAs (siRNAs) were used to regulate Nrf2 expression, while nicotinamide and siRNAs were used to regulate sirtuin 1 (Sirt1) activity and expression, respectively. Mitochondrial superoxide, membrane potential and ATP levels were measured to assess changes in mitochondrial function. Nephrin and synaptopodin expression were measured by western blot analysis. Human podocytes and db/db diabetic mice were used in this study. Results: t-BHQ pretreatment of human podocytes exposed to high glucose (HG) alleviated mitochondrial dysfunction, enhanced the expression of Sirt1, nephrin and synaptopodin and lowered BSA permeability compared with podocytes exposed to HG without t-BHQ pretreatment (p< 0.05). Human podocytes exposed to HG had more severe mitochondrial dysfunction, lower expression of Sirt1, synaptopodin and nephrin and higher BSA permeability than podocytes exposed to HG when Nrf2 expression was downregulated by siRNAs (p< 0.05). The protection provided by activation of the Nrf-ARE pathway in podocytes exposed to HG was partially diminished when Sirt1 expression or activity was decreased by siRNAs or inhibitor compared with podocytes exposed to HG and pretreated with t-BHQ (p< 0.05). When nicotinamide and t-BHQ were both administered to db/db mice, we observed higher levels of urinary albumin/creatinine, lower nephrin and synaptopodin expression, more severe mesangial matrix deposition, collagen deposition on pathological slides and mitochondrial structural damage in podocytes compared to db/db mice treated only with t-BHQ. Conclusions: Our findings suggest that crosstalk between Sirt1 and the Nrf2-ARE anti-oxidative pathway forms a positive feedback loop and that protection provided by t-BHQ activation of the Nrf2-ARE pathway in db/db mice is partly dependent on Sirt1.

Aim This study was designed to evaluate the relationship between sleep quality and hypertension and to determine if there was an association between nondipper blood pressure (BP) and sleep quality in chronic kidney disease (CKD) patients. Methods A total of 775 pre-dialysis CKD patients (314 normal BP patients, 461 hypertension patients) defined as dippers or nondippers by ambulatory BP monitoring were recruited for this study. Demographics and clinical correlates were collected, including body mass index, estimated glomerular filtration rate (eGFR) and other measures. Sleep quality was measured using the Pittsburgh Sleep Quality Index (PSQI). Results A total of 185 (58.9%) patients with normal BP and 341 (74.0%) hypertensive patients had a nondipper BP pattern. The hypertension group had a higher prevalence of the nondipper BP pattern, smoking, alcohol intake and diabetes mellitus (DM) and lower eGFR levels and poorer sleep quality than the normal BP group. Patients with the nondipper BP pattern had lower haemoglobin, worse renal function and poorer sleep quality when compared with hypertensive CKD patients with the dipping BP pattern. PSQI scores were significantly associated with the rate of nocturnal BP decline (P < 0.05) in the hypertension group but not in the normal BP group. Poor sleep quality was an independent factor affecting BP pattern in hypertensive CKD patients using multivariate linear and logistic regression analyses. There was no association between sleep quality and hypertension in CKD patients after multivariate logistic regression analyses. Conclusion Poor sleep quality, which is commonly observed in pre-dialysis CKD patients, is an independent associated factor of the nondipper BP pattern in hypertensive CKD patients. No association was found between poor sleep and nondipper BP in normotensive patients.

Masked hypertension (MHT) and white-coat hypertension (WCHT) have been studied among the general population and hypertensive patients. However, little insight is available on the prognosis of MHT and WCHT in patients with chronic kidney disease (CKD). We investigated the role of MHT and WCHT in the prognosis of patients with non-dialysis CKD.A prospective cohort study was conducted between July 2010 and December 2014. A total of 588 patients with non-dialysis CKD were enrolled for ambulatory and clinic blood pressure (BP) monitoring. Patients were divided into four groups according to levels of clinic and ambulatory BP: normotension (NT), WCHT, MHT, and sustained hypertension (SHT). We recorded the time to: total mortality, renal events, and cardiovascular events. Multivariate Cox regression analyses were explored to ascertain the prognostic value of MHT and WCHT for these end points.Fifty-six CKD patients (9.5%) exhibited WCHT and 121 (20.6%) demonstrated MHT. There were no differences in incidence of total mortality or renal and cardiovascular events between patients with WCHT and those with NT, whereas the occurrence of these three events was higher in patients with MHT and SHT than in patients with NT (P0.05). Moreover, patients with SHT had the highest incidence of renal and cardiovascular events (P0.05). Multivariate Cox regression analyses showed that MHT (vs. NT) and SHT (vs. NT) were associated with an increased risk for total mortality (MHT: hazard ratio [HR], 8.88, 95% confidence interval [CI], 1.04-75.59; SHT: 8.15, 1.02-65.24), renal events (MHT: 3.70, 1.23-11.12; SHT: 3.95, 1.42-11.01), major adverse cardiac and cerebrovascular events (MACCE) (MHT: 8.66, 1.09-68.79; SHT: 11.16, 1.48-84.03), whereas WCHT (vs. NT) was not associated with these risks.MHT (rather than WCHT) is associated with a risk of total mortality, MACCE, and renal events in patients with non-dialysis CKD.

The early initiation of renal replacement therapy has been recommended for patients with acute renal failure by some studies, but its effects on mortality and renal recovery are unknown. We conducted an updated meta-analysis to provide quantitative evaluations of the association between the early initiation of renal replacement therapy and mortality for patients with acute kidney injury. After applying inclusion/exclusion criteria, 51 studies, including 10 randomized controlled trials, with a total of 8179 patients were analyzed. Analysis of the included trials showed that patients receiving early renal replacement therapy had a 25% reduction in all-cause mortality compared to those receiving late renal replacement therapy (risk ratio [RR] 0.75, 95% CI [0.69, 0.82]). We also noted a 30% increase in renal recovery (RR 1.30, 95% CI [1.07, 1.56]), a reduction in hospitalization of 5.84 days (mean difference [MD], 95% CI [–10.27, –1.41]) and a reduction in the duration of mechanical ventilation of 2.33 days (MD, 95% CI [–3.40, –1.26]) in patients assigned to early renal replacement therapy. The early initiation of renal replacement therapy was associated with a decreased risk of all-cause mortality compared with the late initiation of RRT in patients with acute kidney injury. These findings should be interpreted with caution given the heterogeneity between studies. Further studies are needed to identify the causes of mortality and to assess whether mortality differs by dialysis dose.

To investigate the effect of cardiac valve calcification (CVC) on all-cause and cardiovascular mortality in maintenance hemodialysis (MHD) patients. A retrospective cohort study was conducted in 183 long-term hemodialysis patients with complete follow-up data from January 1, 2012, to December 30, 2015. The baseline data between CVC and non-CVC groups were compared. Kaplan–Meier method was used to analyze all-cause and cardiovascular mortality. The effect of CVC on prognosis was analyzed using the Cox proportional hazard regression model and subgroup analysis. Among 183 patients under hemodialysis, 104 (56.8%) were males, with an average age of 56.1 ± 17.0 years and 68 (37.2%) were complicated with valvular calcification. The median follow-up period was 30.8 months. All-cause and cardiovascular mortality were 50% vs. 14.8% and 25% vs. 7.0% in the CVC and non-CVC groups, respectively (P

Aim: This study was carried out to identify the expression profile and role of circRNAs in cisplatin-induced acute kidney injury (AKI). Materials & methods: In this study, an AKI model was established in cisplatin-treated mice, and the expression of circRNAs was profiled by next-generation sequencing. The differential expression levels of selected circRNAs were determined by quantitative real-time polymerase chain reaction. Bioinformatics analysis was conducted to predict the functions. Results: In total, 368 circRNAs were detected to be differentially expressed in response to cisplatin treatment. Bioinformatics analysis indicated that the parental genes of the differentially expressed circRNAs were predominantly implicated in the cell and cell part, cellular process and cancer pathways. Conclusion: CircRNAs might be differentially expressed in AKI, which are potentially involved in pathophysiology of cisplatin-induced nephrotoxicity.

The regulatory roles of long noncoding RNAs (lncRNAs) in transcriptional coactivators are still largely unknown. Here, we have shown that the peroxisome proliferator-activated receptor γ (PPARγ) coactivator α (PGC-1α, encoded by Ppargc1a) is functionally regulated by the lncRNA taurine-upregulated gene 1 (Tug1). Further, we have described a role for Tug1 in the regulation of mitochondrial function in podocytes. Using a murine model of diabetic nephropathy (DN), we performed an unbiased RNA-sequencing (RNA-seq) analysis of kidney glomeruli and identified Tug1 as a differentially expressed lncRNA in the diabetic milieu. Podocyte-specific overexpression (OE) of Tug1 in diabetic mice improved the biochemical and histological features associated with DN. Unexpectedly, we found that Tug1 OE rescued the expression of PGC-1α and its transcriptional targets. Tug1 OE was also associated with improvements in mitochondrial bioenergetics in the podocytes of diabetic mice. Mechanistically, we found that the interaction between Tug1 and PGC-1α promotes the binding of PGC-1α to its own promoter. We identified a Tug1-binding element (TBE) upstream of the Ppargc1a gene and showed that Tug1 binds with the TBE to enhance Ppargc1a promoter activity. These findings indicate that a direct interaction between PGC-1α and Tug1 modulates mitochondrial bioenergetics in podocytes in the diabetic milieu.

Background Masked hypertension and white-coat hypertension have been studied among the general population and in hypertensive patients. However, little insight is available on masked and white-coat hypertension among patients with chronic kidney disease (CKD). Methods We recruited 1322 CKD patients admitted to our hospital division. Patients were divided into four groups: normotension; white-coat hypertension (WCHT); masked hypertension (MHT); sustained hypertension. Multivariable logistic regression analyses were used to evaluate the correlation between WCHT, MHT and renal/cardiovascular parameters. Results The prevalence of WCHT and MHT was 10.21% and 16.11%, respectively. Patients with WCHT and MHT had more severe target-organ damage (TOD) than patients with normotension, but had less severe TOD than patients with sustained hypertension. MHT correlated with impaired renal function and left-ventricular hypertrophy, whereas WCHT was associated with abnormal carotid intima media thickness. Age, body mass index, clinic and 24-h systolic blood pressure correlated with MHT, whereas clinic, 24-h diastolic blood pressure and night-time systolic blood pressure was associated with WCHT. Conclusions Prevalence of WCHT and MHT was 10.21% and 16.11%, respectively. WCHT and MHT show a close relationship with TOD in CKD patients.

Silybin is a secondary metabolite isolated from the seeds of blessed milk thistle (Silybum marianum) that has anti-inflammatory, antioxidative, antifibrotic, and antitumor properties. Here, we showed that silybin protected against cisplatin-induced acute kidney injury (AKI) by improving mitochondrial function through the regulation of sirtuin 3 (SIRT3) expression. Male SV129 and SIRT3 knockout (KO) mice were administered a single intraperitoneal (i.p.) injection of cisplatin with or without treatment with silybin. Moreover, cultured HK2 cells were used to evaluate mitochondrial morphology and function. Our data suggested that silybin enhanced SIRT3 expression after cisplatin administration both in vivo and in vitro. Silybin treatment improved mitochondrial function and bioenergetics in wild-type, but not SIRT3-defective, cells and mice. Moreover, we demonstrated that silybin markedly attenuated cisplatin-induced AKI and tubular cell apoptosis and improved cell regeneration in a SIRT3-dependent manner. Collectively, these results suggest that silybin is a pharmacological activator of SIRT3 capable of protecting against cisplatin-induced tubular cell apoptosis and AKI by improving mitochondrial function. Thus, silybin could serve as a potential clinical renoprotective adjuvant treatment in cisplatin chemotherapy.

Background Irisin is a recently discovered myokine thought to be involved in multiple metabolism abnormalities in most dialysis patients. However, the myokine has not been thoroughly studied in peritoneal dialysis. This study aimed to evaluate serum irisin levels and establish their relation to dialysis adequacy, insulin resistance, and bone metabolism status in patients on peritoneal dialysis. Methods A total of 59 nondiabetic prevalent peritoneal dialysis patients and 52 age- and sex-matched healthy controls were enrolled in this cross-sectional study. Serum irisin concentration was assessed by enzyme-linked immunosorbent assay. The correlations between serum irisin and dialysis adequacy, clinical, and metabolic variables were investigated. Results Serum irisin levels were lower in nondiabetic peritoneal dialysis patients (17.02ng/ml) compared with healthy controls (22.17ng/ml, P

A recent study demonstrated that advanced glycation end products (AGEs) play a role in monocyte infiltration in mesangial areas in diabetic nephropathy. The Ras homolog gene family, member A Rho kinase (RhoA/ROCK) pathway plays a role in regulating cell migration. We hypothesized that the RhoA/ROCK pathway affects adhesion and inflammation in endothelial cells induced by AGEs. Rat glomerular endothelial cells (rGECs) were cultured with AGEs (80 μg/ml) in vitro. The ROCK inhibitor Y27632 (10 nmol/l) and ROCK1-siRNA were used to inhibit ROCK. We investigated levels of the intercellular adhesion molecule 1 (ICAM-1) and monocyte chemoattractant protein1 (MCP-1) in rGECs. Db/db mice were used as a diabetes model and received Fasudil (10 mg/kg/d, n = 6) via intraperitoneal injection for 12 weeks. We found that AGEs increased the expression of ICAM-1 and MCP-1 in rGECs, and the RhoA/ROCK pathway inhibitor Y27632 depressed the release of adhesion molecules. Moreover, blocking the RhoA/ROCK pathway ameliorated macrophage transfer to the endothelium. Reduced expression of adhesion molecules and amelioration of inflammatory cell infiltration in the glomerulus were observed in db/db mice treated with Fasudil. The RhoA/ROCK pathway plays a role in adhesion molecule expression and inflammatory cell infiltration in glomerular endothelial cells induced by AGEs.

Damage to podocytes caused by excessive reactive oxygen species (ROS) contributes to onset and progression of diabetic kidney disease (DKD). Nuclear factor (erythroid-derived 2)-like 2 (Nrf2) is a redox-sensing transcription factor that can induce the expression of antioxidant enzymes. We explored whether activation of Nrf2 pathway attenuated hyperglycemia-induced injuries in mouse podocytes.Tert-Butylhydroquinone (tBHQ) and small interfering RNAs (siRNAs) were used to regulate Nrf2 expression. Apoptosis and intracellular superoxide anion production were measured by flow cytometry. The activity of the Nrf2 antioxidant pathway was measured by an antioxidant response element (ARE)-driven luciferase reporter gene assay, and Nrf2 expression was assessed by real-time PCR and western blot analyses.Podocytes incubated with high-glucose (HG) medium had higher intracellular superoxide anion and hydrogen peroxide production, higher apoptosis rate, higher bovine serum albumin (BSA) permeability and lower synaptopodin expression compared with podocytes exposed normal glucose (NG) (p0.05). tBHQ increased the activity of the Nrf2 antioxidant pathway and enhanced nuclear Nrf2 expression, reduced intracellular superoxide anion and hydrogen peroxide production, apoptosis rate and BSA permeability, and restored synaptopodin expression in podocytes exposed to HG (pO.05). Podocytes with Nrf2 siRNAs showed higher intracellular superoxide anion and hydrogen peroxide production, apoptosis and BSA permeability as well as lower synaptopodin expression compared with podocytes exposed to HG (p0.05).Our findings suggest that protection against activation of the Nrf2-ARE pathway in podocytes exposed to hyperglycemia. Thus, regulation of the Nrf2-ARE pathway could be a therapeutic option to combat oxidative stress and inhibit the development of DKD.

The aim of this study was to investigate the effects of advanced glycation end-products (AGEs) on podocyte adhesion and the underlying mechanisms. Immortalized mouse podocytes were exposed to various conditions and podocyte adhesion was evaluated using a hexosaminidase assay. The expression levels of integrin-linked kinase (ILK) were measured by quantitative polymerase chain reaction (qPCR) and western blotting. Treatment with AGEs resulted in a significant, concentration-dependent reduction in podocyte adhesion (P

The “reverse dipping” blood pressure (BP) pattern has been studied among the general population and in individuals suffering from hypertension. However, the prognosis of this pattern in chronic kidney disease (CKD) patients is not known. We monitored BP throughout the day and followed health outcomes in 588 CKD patients admitted to our hospital. Time to all-cause mortality, cardiovascular mortality, renal events and cardiovascular events was recorded. Multivariate-adjusted Cox regression analyses were carried out to detect the prognostic value of a reverse dipping BP pattern. Prevalence of a “dipper”, “non-dipper” and “reverse dippers” was 34.69%, 43.54% and 18.03%, respectively. Patients with a reverse dipping pattern had a higher prevalence of total mortality, cardiovascular mortality, renal events and cardiovascular events than patients with a dipping pattern (P versus dippers) were associated with a higher risk of total mortality (hazard ratio [HR], 5.08; 95% confidence interval [CI], 1.79~14.47), cardiovascular mortality (4.17; 1.25~13.88), renal events (3.00; 1.59~5.65) and cardiovascular events (4.12; 1.78~9.51) even after adjustment by 24-h systolic BP. These data suggest that a reverse dipping BP pattern, independent of 24-h levels of systolic BP, has prognostic value in CKD patients not undergoing dialysis.

Hyperhomocysteinemia (HHcy) is recognized as a risk factor for cardiovascular disease. However, the prevalence of HHcy and its role in association with target organ damage in patients with chronickidney disease (CKD) are not well understood. This cross-sectional study included 1042 CKD patients who were admitted to our hospital. Patients were divided into two groups: hyperhomocysteinemia and normohomocysteinemia. Multivariable linear regression analyses were used to evaluate the association between plasma homocysteine and renal/cardiovascular parameters. The prevalence of HHcy in patients with CKD was 52.78%, and the prevalence in CKD stage 1, stage 2, stage 3, stage 4 and stage 5 patients was 10.73%, 29.22%, 58.71%, 75.23% and 83.75%, respectively. Patients with HHcy had higher incidences of renal damage, left ventricular hypertrophy, left ventricular diastolic dysfunction and abnormal carotid intima-media thickness compared with patients with normohomocysteinemia (p < 0.05), while multivariable linear regression analyses showed plasma homocysteine was only associated with the estimated glomerular filtration rate (eGFR). eGFR, uric acid, albumin, gender, hemoglobin and calcium×phosphate were associated with levels of plasma homocysteine in these CKD patients. The prevalence of HHcy in Chinese patients with CKD was high, and serum homocysteine levels were associated with impaired renal function in these patients.

INTRODUCTION Dyslipidemia is often detected in patients with chronic kidney disease (CKD). Previous studies of the relationship between lipid profiles and kidney function have yielded variable results. We aimed to investigate the correlation between serum lipid levels and kidney function evaluated by measured glomerular filtration rate (mGFR) in Chinese patients with CKD. METHODS A cross-sectional study was conducted on 2036 Chinese CKD patients who had mGFR. Linear regression analysis was performed to evaluate the correlation between different serum lipid levels and mGFR, while logistic regression analysis was used to investigate the association between CKD stages and the risk of different types of dyslipidemia. RESULTS The mean age was 55 years and the mean mGFR was 63 mL/min/1.73m2. After adjusting for some confounders (age, gender, body mass index, a history of diabetes, fasting glucose, a history of hypertension, systolic blood pressure, diastolic blood pressure, smoking status, hemoglobin, serum potassium, serum albumin, and serum uric acid), serum triglyceride level showed a negative correlation with mGFR (β = -0.006, P = 0.006) in linear regression analysis, and CKD stages were positively related to the risk of hypertriglyceridemia (odds ratios were 1.329, 1.868, 2.514 and P were 0.046, < 0.001, < 0.001 for CKD stage 2, 3, 4/5, respectively) in logistic regression anlysis. CONCLUSIONS Serum triglyceride level is independently association with mGFR. Patients with reduced kidney function are more likely to have higher serum triglyceride levels. Further longitudinal, multicenter and well-conducted studies are needed to provide more evidence.

The early initiation of renal replacement therapy has been recommended for patients with acute renal failure by some studies, but its effects on mortality and renal recovery are unknown. We conducted an updated meta-analysis to provide quantitative evaluations of the association between the early initiation of renal replacement therapy and mortality for patients with acute kidney injury. After applying inclusion/exclusion criteria, 51 studies, including 10 randomized controlled trials, with a total of 8179 patients were analyzed. Analysis of the included trials showed that patients receiving early renal replacement therapy had a 25% reduction in all-cause mortality compared to those receiving late renal replacement therapy (risk ratio [RR] 0.75, 95% CI [0.69, 0.82]). We also noted a 30% increase in renal recovery (RR 1.30, 95% CI [1.07, 1.56]), a reduction in hospitalization of 5.84 days (mean difference [MD], 95% CI [-10.27, -1.41]) and a reduction in the duration of mechanical ventilation of 2.33 days (MD, 95% CI [-3.40, -1.26]) in patients assigned to early renal replacement therapy. The early initiation of renal replacement therapy was associated with a decreased risk of all-cause mortality compared with the late initiation of RRT in patients with acute kidney injury. These findings should be interpreted with caution given the heterogeneity between studies. Further studies are needed to identify the causes of mortality and to assess whether mortality differs by dialysis dose.

Patients with both hypertension and hyperhomocysteinemia, termed H-type hypertension, have a high risk for cardiocerebrovascular diseases. However, little is known about the prevalence of H-type hypertension or its role in target organ damage in patients with chronic kidney disease (CKD). The authors recruited 1042 patients with CKD who were admitted to their hospital division. Multiple linear regression analyses were used to evaluate the association between H-type hypertension and renal/cardiovascular parameters. A total of 460 (44.14%) CKD patients had H-type hypertension. Multivariate logistic regression analysis showed that H-type hypertension is associated with serum albumin, uric acid, estimated glomerular filtration rate (eGFR), and 24-hour systolic blood pressure. Patients with H-type hypertension had the worst renal function and left ventricular hypertrophy among all patients, while the levels of carotid intima-media thickness (cIMT) in patients with H-type hypertension were only slightly higher than in patients with normotension and normohomocysteinemia (P

This study was designed to evaluate the relationship between sleep quality and hypertension and to determine if there was an association between nondipper blood pressure (BP) and sleep quality in chronic kidney disease (CKD) patients.A total of 775 pre-dialysis CKD patients (314 normal BP patients, 461 hypertension patients) defined as dippers or nondippers by ambulatory BP monitoring were recruited for this study. Demographics and clinical correlates were collected, including body mass index, estimated glomerular filtration rate (eGFR) and other measures. Sleep quality was measured using the Pittsburgh Sleep Quality Index (PSQI).A total of 185 (58.9%) patients with normal BP and 341 (74.0%) hypertensive patients had a nondipper BP pattern. The hypertension group had a higher prevalence of the nondipper BP pattern, smoking, alcohol intake and diabetes mellitus (DM) and lower eGFR levels and poorer sleep quality than the normal BP group. Patients with the nondipper BP pattern had lower haemoglobin, worse renal function and poorer sleep quality when compared with hypertensive CKD patients with the dipping BP pattern. PSQI scores were significantly associated with the rate of nocturnal BP decline (P0.05) in the hypertension group but not in the normal BP group. Poor sleep quality was an independent factor affecting BP pattern in hypertensive CKD patients using multivariate linear and logistic regression analyses. There was no association between sleep quality and hypertension in CKD patients after multivariate logistic regression analyses.Poor sleep quality, which is commonly observed in pre-dialysis CKD patients, is an independent associated factor of the nondipper BP pattern in hypertensive CKD patients. No association was found between poor sleep and nondipper BP in normotensive patients.

Podocyte injury plays an important role in glomerulosclerosis in IgA nephropathy (IgAN). Eepithelial-to-mesenchymal transition (EMT) caused by different factors is the main reason for podocyte damage. This study hypothesized that conditioned mesangial medium may induced EMT process of podocytes and thereby lead to glomerular injury or sclerosis.Podocytes were incubated in medium from mesangial cells incubated with aggregated IgA1(aIgA1) isolated from IgAN patients. Wortmannin were used to inhibit phosphatidylinositol-3-kinase (PI3-K) in podocytes.Western blot analysis, real-time PCR and confocal fluorescent microscopy demonstrated that reduced expression of P-Cadherin, Zonula occludens-1 (ZO-1) and podocin, increased expression of fibroblast -specific protein (FSP-1), α-smooth muscle action(α-SMA) and desmin in podocytes exposed to medium from mesangial cells incubated with aIgA1 isolated from IgAN patients compared with podocytes cultured in RPMI 1640 medium containing 0.5% fetal bovine serum ( FBS) (p0.05). Mesangial medium resulted in a greater albumin influx across the podocyte monolayer (p0.05). Phosphorylation of Akt increased with this medium, as indicated by an increase in the p-Akt/Akt ratio. Treatment with wortmannin partly restored the changes in epithelial and mesenchymal markers and albumin influx. IgAN patients with massive proteinuria showed remarkable α-SMA and FSP-1 expression in podocytes.Our findings indicated that mesangial medium from cells incubated with aIgA1 isolated from IgAN patients induced EMT in podocytes and the PI3-K/ Akt-signaling pathway was involved in the process.

The present study aimed to investigate the effects of advanced glycation end‑products (AGEs) on the permeability of glomerular endothelial cells (GEnCs) and determine whether enhanced permeability was due to degradation of tight junction (TJ) complexes by matrix metalloproteinases (MMPs). Cultured monolayers of GEnCs were exposed to AGEs at different doses and treatment durations in the presence or absence of the organic MMP‑2/9 inhibitor (2R)‑2‑((4‑biphenyl sulfony‑l)amino)‑3‑phenylproprionic acid) (BiPs). Expression of the TJ proteins occludin and claudin‑5 was determined by western blot analysis and immunofluorescence, while the permeability of the GEnCs was measured using transendothelial electrical resistance and by diffusion of 4 kDa fluorescein isothiocyanate (FITC)‑dextran. The activities of MMP‑2 and MMP‑9 were assayed using gelatin zymography. The results indicated that AGE‑treated cultures significantly reduced occludin and claudin‑5 immunoreactivity. Similarly, the surface expression of these proteins was significantly reduced and rows of TJs which normally connect endothelial cells became discontinuous or fractured following AGE exposure. Disruption of TJs was accompanied by significantly reduced transendothelial resistance and hyperpermeability to FITC‑dextran. Treatment with AGEs evoked a dose‑ and time‑dependent upregulation of MMP‑2 and MMP‑9. However, co‑administration of AGEs and BiPS, an inhibitor of MMP‑2/MMP‑9, inhibited the downregulation of occludin and claudin‑5, with a concomitant reversal of GEnC monolayer hyperpermeability. In conclusion, AGEs promoted glomerular hyperpermeability in vitro by the MMP‑mediated disruption of TJs. Chronic elevation of endothelial cell AGEs in diabetes mellitus may contribute to glomerular hyperpermeability by inducing the overexpression of MMPs, which degrade TJs, leading to proteinuria.

Background The ambulatory arterial stiffness index (AASI) can be used to predict cardiovascular morbidity and mortality in hypertensive patients. However, data on AASI in Chinese patients with chronic kidney disease (CKD) is not available. Methods This cross-sectional study enrolled 583 CKD patients. Univariate and multivariate analyses were used to evaluate the relationship between AASI and renal function and parameters of cardiovascular injury. Results Patients with a higher AASI had a higher systolic blood pressure, a lower estimated glomerular filtration rate (eGFR), a higher serum cystatin C, a higher left ventricular mass index (LVMI) and carotid intima-media thickness (cIMT). Univariate analyses showed that AASI was positively correlated with serum cystatin C (r=0.296, P r=0.182, P r = 0.205, P r = –0.200, P Conclusions These data suggest that AASI was closely correlated with renal function and parameters of cardiovascular injury in Chinese CKD patients. Good quality, long-term, large longitudinal trials to validate the role of AASI in clinical practice for Chinese CKD patients.

Background Endothelial dysfunction is an early sign of diabetic cardiovascular disease and may contribute to progressive diabetic nephropathy (DN). There is increasing evidence that dysfunction of the endothelial tight junction is a crucial step in the development of endothelial hyperpermeability, but it is unknown whether this occurs in glomerular endothelial cells (GEnCs) during the progression of DN. We examined tight junction dysfunction of GEnCs during early-stage DN and the potential underlying mechanisms. We also examined the effect of simvastatin (3-Hydroxy-3-methylglutaryl CoA reductase inhibitor) on dysfunction of the tight junctions of cultured GEnCs and in db/db mice with early-stage DN. Methods We assessed the expression of occludin and ZO-1, two major components of the tight junction complex, in cultured rat GEnCs treated with high glucose and in 12 week-old db/db mice with early-stage DN. We also investigated activation of RhoA/ROCK1 signaling, GEnC permeability, and renal function of the mice. Results High glucose suppresses occludin expression and disrupts occludin/ZO-1 translocation in GEnCs. These changes were associated with increased permeability to albumin and activation of RhoA/ROCK1 signaling. Occludin and ZO-1 dysregulation also occurred in the glomeruli of mice with early-stage DN, and these abnormalities were accompanied by albuminuria and activation of RhoA/ROCK1 in isolated glomeruli. Simvastatin prevented high glucose or hyperglycemia-induced dysregulation of occludin and ZO-1 by inhibition of RhoA/ROCK1 signaling in cultured GEnCs and in db/db mice with early-stage DN. Conclusion Our results indicate that activation of RhoA/ROCK1 by high glucose disrupts the expression and translocation of occludin/ZO-1 and that simvastatin alleviates occludin/ZO-1 dysregulation and albuminuria by suppressing RhoA/ROCK1 signaling during early-stage DN. These results suggest a potential therapeutic strategy for preventing the onset of albuminuria in early-stage DN.

Background IgA nephropathy (IgAN) is characterized by mesangial deposition of polymeric IgA1, and podocyte injury plays an important role in glomerulosclerosis of the disease. Our previous study indicated that medium of mesangial cells co-incubated with aggregated IgA1 (aIgA1), isolated from IgAN patients, down-regulated nephrin expression. Yet the mechanism remains unclear. Materials and methods Podocytes were incubated with a medium of mesangial cells co-incubated with aIgA1, which was isolated from IgAN patients, and enalaprilat (10−5 M), valsartan (10−5 M) and anti-mouse tumour necrosis factor-α antibody (50 ng mL−1) separately. Nephrin expression in podocytes was measured by real-time polymerase chain reaction and Western blot analysis. Results The level of angiotensinogen and angiotensin-converting enzyme mRNAs in podocytes, as well as angiotensin, was also increased by a medium of mesangial cells co-incubated with aIgA1 from IgAN patients(P

Purpose: To investigate the influence of IgA1 isolated from IgA nephropathy (IgAN) patients on integrin-linked kinase (ILK) synthesis and adhesive capacity of podocytes through indirect pathways. Methods: IgA1 was isolated from healthy control or IgAN patients’ sera using jacalin affinity chromatography and S-200 chromatography. Podocytes were treated with medium from mesangial cells incubated with aggregated IgA1 (aIgA1, 100 ?g/ml), in the presence or absence of valsartan (10-5M) or neutralizing antibodies of tumor necrosis factor-? (TNF-?, 50 ng/ml). Adhesive capacity of podocytes was assessed by cell counting manually and hexosaminidase assay. Real-time PCR and western blotting were used to detect the expression of ILK. Results: Medium from mesangial cells incubated with aIgA1 from IgAN patients reduced podocyte adhesion to collagen compared with medium from mesangial cells incubated with control medium(RPMI-1640 with 0.5% FBS) (35.0±4.8% vs. 60.0±2.0%; P < 0.05). While medium from mesangial cells incubated with aIgA1 from IgAN patients upregulated ILK expression in podocytes at mRNA and protein levels compared with medium from mesangial cells without aIgA1 incubated (1.6-fold and 1.38-fold higher than control, respectively, P < 0.05). Defects in podocyte adhesion and up-regulation of ILK synthesis induced by medium from mesangial cells incubated with aIgA1 from IgAN patients can be partially reversed by the pre-treatment for 1 hour with valsartan(P < 0.05), while pre-treatment with neutralizing antibodies of TNF-? produced no protective effect on podocytes (P > 0.05). Conclusion: Serum IgA1 from IgAN patients may inhibit adhesive capacity and up-regulate ILK synthesis in podocytes through indirect pathways.

SUMMARY Aim: Abnormal immunoglobulin (Ig)A1 is considered to play a pivotal role in IgA nephropathy. We used mouse podocytes as the experimental model to investigate the effect of aggregated IgA1 (aIgA1) isolated from IgA nephropathy (IgAN) patients on nephrin expression in podocytes through direct and indirect pathways. Methods: Jacalin affinity chromatography and Sephacryl S-200 molecular sieve chromatography were used to isolate IgA1 from blood of IgAN patients which was therefore became aIgA1. Podocytes were incubated with aIgA1 or special mesangial medium. Nephrin expression in podocytes was measured by real-time polymerase chain reaction and western blot analysis. Results: Aggregated IgA1 from IgAN patients and healthy controls reduced nephrin expression in podocytes at mRNA and protein levels when compared with podocytes incubated with control medium (RPMI-1640 with 0.5% foetal bovine serum) (P