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ObjectivesTo examine whether urinary excretion of cysteine-rich protein 61 (Cyr61), an acknowledged proinflammatory factor in kidney pathologies, increases in chronic kidney disease (CKD) and is associated with subsequent rapid kidney function decline.DesignAn observational cohort study.SettingIn the nephrology outpatient clinics of a tertiary hospital in Taiwan.ParticipantsWe enrolled 138 adult CKD outpatients (n=12, 32, 18, 18, 29 and 29 in stages 1, 2, 3a, 3b, 4 and 5 CKD, respectively) between February and October 2014 and followed them for 1 year. Their mean age was 60.46±13.16 years, and 51 (37%) of them were women.Primary outcome measuresUrinary Cyr61 levels were measured by ELISA. Rapid kidney function decline was defined as an estimated glomerular filtration rate (eGFR) decline rate ≥ 4 mL/min/1.73 m2/year or developing end-stage renal disease during subsequent 3-month or 1-year follow-up period. Models were adjusted for demographic and clinical variables.ResultsThe urine Cyr61-to-creatinine ratio (UCyr61CR) increased significantly in patients with stage 4 or 5 CKD. Multivariable linear regression analysis showed that log(UCyr61CR) was positively correlated with log(urine protein-to-creatinine ratio) (pConclusionsElevated urinary Cyr61 excretion is associated with rapid short-term kidney function deterioration in patients with CKD. Measuring urinary Cyr61 excretion is clinically valuable for monitoring disease trajectory and may guide treatment planning.

In adults, membranous nephropathy (MN) is a major cause of nephrotic syndrome. However, the etiology of approximately 75% of MN cases is idiopathic. Secondary causes of MN are autoimmune diseases, infection, drugs, and malignancy. The pathogenesis of MN involves formation of immune complex in subepithelial sites, but the definite mechanism is still unknown. There are three hypotheses about the formation of immune complex, including preformed immune complex, in situ immune-complex formation, and autoantibody against podocyte membrane antigen. The formation of immune complex initiates complement activation, which subsequently leads to glomerular damage. Recently, the antiphospholipase A2 receptor antibody was found to be associated with idiopathic MN. This finding may be useful in the diagnosis and prognosis of MN. The current treatment includes best supportive care, which consists of the use of angiotensin-converting enzyme inhibitors/angiotensin II receptor blockers, lipid-lowering agents, and optimal control of blood pressure. Immunosuppressive agents should be used for patients who suffer from refractory proteinuria or complications associated with nephrotic syndrome. Existing evidence supports the use of a combination of steroid and alkylating agents. This article reviews the epidemiology, pathogenesis, diagnosis, and the treatment of MN.

Fibrosis of the peritoneal cavity remains a serious, life-threatening problem in the treatment of kidney failure with peritoneal dialysis. The mechanism of fibrosis remains unclear partly because the fibrogenic cells have not been identified with certainty. Recent studies have proposed mesothelial cells to be an important source of myofibroblasts through the epithelial–mesenchymal transition; however, confirmatory studies in vivo are lacking. Here, we show by inducible genetic fate mapping that type I collagen–producing submesothelial fibroblasts are specific progenitors of α-smooth muscle actin–positive myofibroblasts that accumulate progressively in models of peritoneal fibrosis induced by sodium hypochlorite, hyperglycemic dialysis solutions, or TGF-β1. Similar genetic mapping of Wilms’ tumor-1–positive mesothelial cells indicated that peritoneal membrane disruption is repaired and replaced by surviving mesothelial cells in peritoneal injury, and not by submesothelial fibroblasts. Although primary cultures of mesothelial cells or submesothelial fibroblasts each expressed α-smooth muscle actin under the influence of TGF-β1, only submesothelial fibroblasts expressed α-smooth muscle actin after induction of peritoneal fibrosis in mice. Furthermore, pharmacologic inhibition of the PDGF receptor, which is expressed by submesothelial fibroblasts but not mesothelial cells, attenuated the peritoneal fibrosis but not the remesothelialization induced by hypochlorite. Thus, our data identify distinctive fates for injured mesothelial cells and submesothelial fibroblasts during peritoneal injury and fibrosis.

Blood pressure control with renin-angiotensin system (RAS) blockade has remained the gold standard for treating patients with proteinuric chronic kidney disease (CKD) up to date. Nevertheless, RAS blockade slows but does not halt the progression of kidney disease, thus highlighting the need to search for additional therapeutic approaches. The nonselective phosphodiesterase (PDE) inhibitor pentoxifylline (PTX) is an old drug that exhibits prominent anti-inflammatory, anti-proliferative and anti-fibrotic activities both in vitro and in vivo. Studies in human subjects have shown that PTX monotherapy decreases urinary protein excretion, and add-on therapy of PTX to background RAS blockade additively reduces proteinuria in patients with CKD of various etiology. More recent studies find that PTX combined with RAS blockade delays the decline of glomerular filtration rate in diabetic patients with mild to moderate CKD, and reduces the risk of end-stage renal disease in diabetic and non-diabetic patients in late stage of CKD with high proteinuria levels. In this review, we update the clinical trial results of PTX as monotherapy, or in conjunction or in comparison with RAS blockade on patients with proteinuria and CKD, and propose a mechanistic scheme explaining the renoprotective activities of this drug.

Background/PurposeSeveral studies have shown the renoprotective effects of pentoxifylline in the treatment of chronic kidney disease (CKD). This study was conducted to examine whether there was an increased benefit of including pentoxifylline with angiotensin-converting enzyme inhibitor (ACEI) or angiotensin II receptor blocker (ARB) in the treatment of CKD.MethodsA single-center retrospective analysis was conducted. A total of 661 Stage 3B-5 CKD patients who received ACEI or ARB treatment were recruited. The patients were divided into the pentoxifylline use group and the no pentoxifylline group. Renal survival analysis of the two groups was compared. Subgroup analysis was performed by dividing the patients into lower [urine protein to creatinine ratio (UPCR)

Pericytes have been identified as the major source of precursors of scar-producing myofibroblasts during kidney fibrosis. The underlying mechanisms triggering pericyte-myofibroblast transition are poorly understood. Transforming growth factor β-1 (TGF-β1) is well recognized as a pluripotent cytokine that drives organ fibrosis. We investigated the role of TGF-β1 in inducing profibrotic signaling from epithelial cells to activate pericyte-myofibroblast transition. Increased expression of TGF-β1 was detected predominantly in injured epithelium after unilateral ureteral obstruction, whereas downstream signaling from the TGF-β1 receptor increased in both injured epithelium and pericytes. In mice with ureteral obstruction that were treated with the pan anti–TGF-β antibody (1D11) or TGF-β receptor type I inhibitor (SB431542), kidney pericyte-myofibroblast transition was blunted. The consequence was marked attenuation of fibrosis. In addition, epithelial cell cycle G2/M arrest and production of profibrotic cytokines were both attenuated. Although TGF-β1 alone did not trigger pericyte proliferation in vitro, it robustly induced α smooth muscle actin (α-SMA). In cultured kidney epithelial cells, TGF-β1 stimulated G2/M arrest and production of profibrotic cytokines that had the capacity to stimulate proliferation and transition of pericytes to myofibroblasts. In conclusion, this study identified a novel link between injured epithelium and pericyte-myofibroblast transition through TGF-β1 during kidney fibrosis.

Summary BackgroundandobjectivesRelativelylittleisknownaboutthelong-termoutcomesofdifferenthistologictypesof primary glomerulonephritis in Asian populations. Design, setting, participants, & measurements From 1993 to 2006, 987 patients undergoing renal biopsy were studied, and 580 patients (mean age=44.4 years, male=58.5%) with the four most common forms of glomerulonephritis (membranous nephropathy, focal and segmental glomerulosclerosis,IgA nephropathy, and minimal change disease) were selected for analysis. Median follow-up period was 5.9 (interquartile range=5.7) years. Results The focal and segmental glomerulosclerosis group displayed the highest incidence of ESRD (25.8%) and the fastest decline of estimated GFR (4.6 ml/min per 1.73 m 2 per year). The IgA nephropathy group also had a higher rate of ESRD than the membranous nephropathy patients (19.2% versus 4.3%, P,0.001). In contrast, the membranous nephropathy group exhibited an overall death rate similar to the focal and segmental glomerulosclerosis group (17.2% versus 14.4%) but higher than the IgA nephropathy and minimal change disease patients (4.6% and 3.7%, respectively, P,0.001). The most powerful predictor for ESRD was focal and segmental glomerulosclerosis, whereas the strongest predictor for all-cause mortality was membranous nephropathy with higher proteinuria. Protectors against ESRD included male sex and higher hemoglobin. Conclusions Most predictors for ESRD and overall mortality found in this ethnic Chinese cohort were similar to other studies. However, some risk factors linked with distinct glomerular pathologies displayed differential clinical outcomes. Clin J Am Soc Nephrol 7: ccc–ccc, 2012. doi: 10.2215/CJN.04500511

BACKGROUND Hemodialysis patients suffer from poor quality of life and survival. A retrospective cohort study was performed to examine the sex differences in self-reported quality of life and mortality in a Taiwanese hemodialysis cohort. METHODS A total of 816 stable hemodialysis patients were included. Patients completed two questionnaires: the 36-item Short Form Health Survey Questionnaire (SF-36, Taiwan Standard Version 1.0) to assess health-related quality of life (HRQoL) and the Beck Depression Inventory (BDI, Chinese Version) to assess depressive mood. Mortality outcomes were recorded for a seven-year follow-up period. RESULTS After adjustment for confounding factors, women had significantly higher BDI scores (P=.003), lower physical functioning (P

Pericytes are the major source of scar-producing myofibroblasts following kidney injury; however, the mechanisms of this transition are unclear. To clarify this, we examined Collagen 1 (α1)-green fluorescent protein (GFP) reporter mice (pericytes and myofibroblasts express GFP) following ureteral obstruction or ischemia–reperfusion injury and focused on the role of platelet-derived growth factor (PDGF)-receptor (PDGFR) signaling in these two different injury models. Pericyte proliferation was noted after injury with reactivation of α-smooth muscle actin expression, a marker of the myofibroblast phenotype. PDGF expression increased in injured tubules, endothelium, and macrophages after injury, whereas PDGFR subunits α and β were expressed exclusively in interstitial GFP-labeled pericytes and myofibroblasts. When PDGFRα or PDGFRβ activation was inhibited by receptor-specific antibody following injury, proliferation and differentiation of pericytes decreased. The antibodies also blunted the injury-induced transcription of PDGF , transforming growth factor β1 , and chemokine CCL2. They also reduced macrophage infiltration and fibrosis. Imatinib, a PDGFR tyrosine kinase inhibitor, attenuated pericyte proliferation and kidney fibrosis in both fibrogenic models. Thus, PDGFR signaling is involved in pericyte activation, proliferation, and differentiation into myofibroblasts during progressive kidney injury. Hence, pericytes may be a novel target to prevent kidney fibrosis by means of PDGFR signaling blockade.

Existing chronic kidney disease (CKD) is among the most potent predictors of postoperative acute kidney injury (AKI). Here we quantified this risk in a multicenter, observational study of 9425 patients who survived to hospital discharge after major surgery. CKD was defined as a baseline estimated glomerular filtration rate45 ml/min per 1.73 m(2). AKI was stratified according to the maximum simplified RIFLE classification at hospitalization and unresolved AKI defined as a persistent increase in serum creatinine of more than half above the baseline or the need for dialysis at discharge. A Cox proportional hazard model showed that patients with AKI-on-CKD during hospitalization had significantly worse long-term survival over a median follow-up of 4.8 years (hazard ratio, 1.7) [corrected] than patients with AKI but without CKD.The incidence of long-term dialysis was 22.4 and 0.17 per 100 person-years among patients with and without existing CKD, respectively. The adjusted hazard ratio for long-term dialysis in patients with AKI-on-CKD was 19.8 compared to patients who developed AKI without existing CKD. Furthermore, AKI-on-CKD but without kidney recovery at discharge had a worse outcome (hazard ratios of 4.6 and 213, respectively) for mortality and long-term dialysis as compared to patients without CKD or AKI. Thus, in a large cohort of postoperative patients who developed AKI, those with existing CKD were at higher risk for long-term mortality and dialysis after hospital discharge than those without. These outcomes were significantly worse in those with unresolved AKI at discharge.

OBJECTIVES: To obtain information about the effect of prolonged aldosterone excess on kidney function. METHODS: We determined kidney function changes defined by cystatin C-based estimations of glomerular filtration rate (CysC-GFR). Pretreatment proteinuria and intrarenal Doppler velocimetric indices in primary aldosteronism were examined and followed after adrenalectomy or spironolactone treatment. RESULTS: This prospective, multicenter study included 130 primary aldosteronism patients (56 men; age, 49.9 ± 13.4 years: 100 with adenoma and 30 with idiopathic hyperaldosteronism) and 73 essential hypertension patients (36 men; age, 51.4 ± 14.8 years) as controls. Patients with primary aldosteronism had higher CysC-GFR (P < 0.05) and heavier proteinuria (0.042) than those with essential hypertension. With primary aldosteronism, a higher aldosterone-renin ratio (odds ratio, OR = 7.85, P = 0.008) was independently related to pretreatment CysC-GFR. The factors related to pretreatment proteinuria included CysC-GFR (OR, -0.006, P = 0.001), plasma aldosterone concentration (OR, 0.004, P = 0.002), and duration of hypertension (OR, 0.016, P = 0.032). Duration of hypertension was also independently correlated with the pretreatment resistive index among primary aldosteronism patients (OR, 0.004, P = 0.035). CysC-GFR (all, P < 0.05), proteinuria (P < 0.001), and resistive index (P < 0.001) decreased 1 year after adrenalectomy but not with spironolactone treatment. CONCLUSION: Our data suggest that prolonged hyperaldosteronism will cause relative kidney hyperfiltration and reversible intrarenal vascular structural changes, which disguise the consequent renal injury, including declining GFR and proteinuria. Adrenalectomy and spironolactone treatment exert different clinical impacts toward kidney damage even with a similar blood pressure-lowering effect.

Sleep disturbance is common in dialysis patients and is associated with the development of enhanced inflammatory responses. Cognitive-behavioral therapy is effective for sleep disturbance and reduces inflammation experienced by peritoneal dialysis patients; however, this has not been studied in hemodialysis patients. To determine whether alleviation of sleep disturbance in hemodialysis patients also leads to less inflammation, we conducted a randomized controlled interventional study of 72 sleep-disturbed hemodialysis patients. Within this patient cohort, 37 received tri-weekly cognitive-behavioral therapy lasting 6 weeks and the remaining 35, who received sleep hygiene education, served as controls. The adjusted post-trial primary outcome scores of the Pittsburgh Sleep Quality Index, the Fatigue Severity Scale, the Beck Depression Inventory, and the Beck Anxiety Inventory were all significantly improved from baseline by therapy compared with the control group. The post-trial secondary outcomes of high-sensitive C-reactive protein, IL-18, and oxidized low-density lipoprotein levels significantly declined with cognitive-behavioral therapy in comparison with the control group. Thus, our results suggest that cognitive-behavioral therapy is effective for correcting disorganized sleep patterns, and for reducing inflammation and oxidative stress in hemodialysis patients.

Background Though aldosterone–renin ratio (ARR) is the current routine screening method for suspicious primary aldosteronism, we hypothesized that the simple formula combining body mass index (BMI) and serum potassium to urine potassium clearance (PUKC) ratio was comparable to ARR. Methods Records of patients who were referred to the National Taiwan University Hospital for investigation of primary aldosteronism from January 1995 through December 2007 were retrieved. Primary aldosteronism was diagnosed based on the modified 4-corners criteria, otherwise essential hypertension was diagnosed. In both groups, the PUKC/BMI ratio was determined as well as the ARR. Bland–Altman and mountain-plot analysis were used to validate the agreement between ARR and PUKC/BMI. Receiver operating characteristic (ROC) curves were used to compare the sensitivity and specificity of PUKC/BMI and ARR. Results The records for urinary potassium were analyzed for 177 hypertensive patients (134 patients with primary aldosteronism). ROC curves showed comparable areas under the curves of both methods (95% CI: − 0.029 to 0.183; p = 0.186). Bland–Altman analysis further supported the agreement between ARR and PUKC/BMI ratio. Conclusions We found that the screening power of PUKC/BMI was as good as that of conventional ARR. With the quick and extensive availability of the PUKC/BMI method and its equivalence to ARR, this screening strategy would be a good first-line tool for massive community-based primary aldosteronism surveys.

Hyperphosphataemia in end-stage renal disease (ESRD) is a major contributor to the development of cardiovascular disease. It has been proposed that the phosphate binder sevelamer has pleiotropic properties. The aim of this study was to evaluate the effects of sevelamer compared with calcium acetate on serum lipid profiles, uric acid and reactive oxygen species in haemodialysis patients with hyperphosphataemia.An 8-week, randomized, open-label, parallel-group study was conducted after a 2-week washout period. A total of 52 patients with ESRD on maintenance haemodialysis were screened for enrolment; 26 patients were randomized to each of the sevelamer and calcium acetate groups. Reactive oxygen species (ROS) production, i.e. superoxide and hydrogen peroxide (H2O2)-related radicals, were detected by chemiluminescence measurement with lucigenin and luminol, respectively.There were no significant differences between treatment groups in changes in serum phosphorus (p=0.378) and adjusted serum calcium levels (p=0.980), but there were more hypercalcaemic events in the calcium acetate group (12.0% vs 3.7%) during treatment. Total serum cholesterol (p0.001) and low-density lipoprotein (LDL) cholesterol (p0.001) levels decreased significantly compared with baseline in the sevelamer group. The decreases in total serum cholesterol and LDL cholesterol were correlated with the reductions in serum phosphorus levels during sevelamer treatment (correlation coefficient [r]=0.266 and 0.386, respectively). Serum uric acid decreased significantly in the sevelamer group (p=0.020), and this change was correlated with serum phosphorus changes (r=0.458). Decreases in plasma H2O2-related radicals, the major oxidative stressor in ROS (p0.001), but not superoxide (p=0.593), were observed after sevelamer treatment.The improvements in multiple lipid surrogates, uric acid and ROS seen in this study show that sevelamer is a promising therapy for treatment of hyperphosphataemia in maintenance haemodialysis patients with a high risk of cardiovascular disease.

Microvascular pericytes and perivascular fibroblasts have recently been identified as the source of scar-producing myofibroblasts that appear after injury of the kidney. We show that cross talk between pericytes and endothelial cells concomitantly dictates development of fibrosis and loss of microvasculature after injury. When either platelet-derived growth factor receptor (R)-β signaling in pericytes or vascular endothelial growth factor (VEGF)R2 signaling in endothelial cells was blocked by circulating soluble receptor ectodomains, both fibrosis and capillary rarefaction were markedly attenuated during progressive kidney injury. Blockade of either receptor-mediated signaling pathway prevented pericyte differentiation and proliferation, but VEGFR2 blockade also attenuated recruitment of inflammatory macrophages throughout disease progression. Whereas injury down-regulated angiogenic VEGF164, the dys-angiogenic isomers VEGF120 and VEGF188 were up-regulated, suggesting that pericyte-myofibroblast differentiation triggers endothelial loss by a switch in secretion of VEGF isomers. These findings link fibrogenesis inextricably with microvascular rarefaction for the first time, add new significance to fibrogenesis, and identify novel therapeutic targets.

Peritoneal fibrosis (PF), including simple sclerosis and encapsulating peritoneal sclerosis (EPS), is a serious complication in patients on long-term peritoneal dialysis. Tamoxifen has successfully been used in treating EPS; however, the mechanism of tamoxifen in treating EPS fibrosis disorders remains unclear. This study demonstrates a possible antifibrotic mechanism of tamoxifen. A bleach-induced PF rat model was applied as the in vivo treatment target. Tamoxifen was intraperitoneally injected daily to treat PF. The PF scores and thickness of the submesothelial zone over the liver surface were measured as indicators for the severity of PF. Human peritoneal mesothelial cells (HPMC) were used as an in vitro model to test the antifibrotic effect of tamoxifen. Gene expressions of transforming growth factors-β (TGF-β), connective tissue growth factor (CTGF) and collagen were investigated using quantitative polymerase chain reactions. In HPMC, tamoxifen showed paradoxical effects between collagen I and TGF-β. Tamoxifen also inhibited TGF-β-induced collagen and CTGF. The possible antifibrotic effect of tamoxifen is through inhibiting CTGF to block collagen synthesis, although it enhances TGF-β which increases fibrosis. These results provide a possible molecular mechanism for tamoxifen.

The maintenance of good health-related quality of life (HRQoL) is an important goal for end-stage renal disease (ESRD) patients. Whether hemodialysis (HD) and peritoneal dialysis (PD) have different impacts on HRQoL is a concern shared by both physicians and patients. A comparison study of HRQoL between Taiwanese HD and PD patients was conducted. ESRD patients at 14 hospitals or dialysis centers in northern Taiwan were recruited in this cross-sectional study. The Chinese-language version of the 36-item Short Form Health Survey Questionnaire (SF-36, Taiwan Standard Version 1.0) was used to evaluate HRQoL. Ordinal regression analyses were used to explore the independent association between HRQoL scores and dialysis modality. By Bonferroni correction test, a P value of

Background: Dialysis patients with uremic pruritus have worse outcomes. However, the pathophysiology of the high mortality in these patients remains inconclusive except for links with calcium/phosphate imbalance and sleep disturbance. Whether inflammation, an outcome predictor in dialysis patients, plays a role is unknown. Methods: This prospective study included 321 chronic hemodialysis (HD) patients ( >3 months) for survival analysis. A visual analog scale (VAS) was used to measure the severity of itching, and the patients were divided into four groups: no pruritus (VAS = 0, N = 118), mild (VAS 1–3, N = 76), moderate (VAS 4–7, N = 89) and severe pruritus (VAS 8–10, N = 38). The Pittsburgh Sleep Quality Index (PSQI) was used to define sleep disturbance, while high-sensitive C-reactive protein (hs-CRP) and tumor necrosis factor α (TNF-α) were used to evaluate inflammation. The patients were followed-up for 30 months. Results: Patients with moderate/severe pruritus had higher hs-CRP, but similar TNF-α levels; they also had a worse survival rate ( P = 0.0197, log rank test). By stratifying hs-CRP levels, those with higher hs-CRP had worse survival regardless of the severity of uremic pruritus. In a Cox proportional hazard model, hs-CRP levels and moderate/severe uremic pruritus were independent predictors of mortality after adjusting for age, poor sleeper (PSQI > 5), diabetes, albumin, phosphate, hemoglobin and parathyroid hormone levels and (hs-CRP) × (moderate/severe uremic pruritus) (all P < 0.05). Conclusion: In moderate/severe pruritic HD patients, those with higher hs-CRP suffer from worse overall mortality. Inflammation may bridge uremic pruritus to high mortality, and elevated hs-CRP predicts a worse outcome in this population.

OBJECTIVE To assess, in a retrospective cohort, urinary tract urothelial carcinoma (UT-UC) in patients with various stages of chronic kidney disease (CKD) and their clinicopathological features, as patients with end-stage renal disease (ESRD) have a higher incidence of UT-UC, but the relationship between early stages of CKD and characteristics of UT-UC are less well known. PATIENTS AND METHODS The study included 267 patients with pathologically confirmed UT-UC from January 1994 to December 2006; all had a physical examination (blood pressure), and measurements of laboratory data (serum creatinine, serum haemoglobin) and pathological data. The glomerular filtration rate (GFR) was calculated using the Modification of Diet in Renal Disease equation. Patients were divided into three groups by individual GFR (mL/min), i.e. >60 (no/mild CKD), 30–60 (CKD stage 3) and

This study evaluated the correlations between spiritual beliefs and health-related quality of life (HRQOL) of hemodialysis (HD) patients in Taiwan. Participants had to complete two questionnaires: the 36-item Short Form Health Survey Questionnaire and the Royal Free Interview for Spiritual and Religious Beliefs. They were then divided into three groups according to their strength of spiritual beliefs—having no, weak, or strong beliefs. Demographic, clinical, and laboratory data among groups were compared. Correlations between spiritual beliefs and HRQOL were then determined by the analysis of covariance and the post hoc Scheffe tests. Six hundred thirty-three patients completed the study. There were more women in the group of patients with strong beliefs (P = 0.005) and more less-educated patients in the group of patients with weak beliefs (P = 0.005). Patients with no or with strong spiritual beliefs had higher role physical (P = 0.01) and social functioning (SF) (P = 0.001) scores than patients with weak beliefs. After adjustment for gender, age, marital status, education, comorbidities, and time on dialysis, patients with no or with strong spiritual beliefs were found to have higher SF scores (P = 0.02) than patients with weak beliefs. HD patients with no or strong spiritual beliefs had higher SF HRQOL than those with weak spiritual beliefs.

Lysophosphatidic acid (LPA) and its specific G-protein-coupled receptors have mitogen-like activities in cellular signal transduction. At the intracellular level, LPA is produced by phospholipase A1 (PLA1) or PLA2; at the extracellular level, LPA is produced by autotaxin/lysophospholipase D. Lipid phosphate phosphatases (LPPs) dephosphorylate LPA and thereby attenuate LPA signaling. Chronic kidney diseases (CKDs) and end-stage renal disease (ESRD) are significant public health issues throughout the world. In these conditions, there is a production and accumulation of transforming growth factor (TGF-β) and connective tissue growth factor (CTGF), leading to accumulation of extracellular matrix proteins and renal fibrosis. In addition, CKD risk factors such as diabetes mellitus, hypertension, dyslipidemia, and activation of the renin-angiotensin- aldosterone system can lead to overexpression of the TGF-β-CTGF-collagen/fibronectin axis and thereby accelerate formation of renal fibrosis. More than five LPA receptors (LPA1 - LPA5) have been identified and have been shown to be expressed in different tissues. LPA1 mediates lung and renal fibrosis following injury, and Ki16425 has been shown to be an antagonist of the LPA1 receptor and an attenuator of fibrosis formation. In this review, we provide a brief update on the concepts of renal fibrosis and the pathogenetic roles of the different LPA signaling pathways, discuss some recent patents on pharmaceuticals that disrupt these pathways, and introduce some pilot studies that have explored the therapeutic potentials of LPA receptor antagonists for management of renal fibrosis.

Background. Increased inflammation has been noted in sleep disorder patients with normal renal function. However, the relationship between sleep quality and circulating inflammatory markers has not been previously studied in haemodialysis (HD) patients. Methods. A total of 114 HD end-stage renal disease patients receiving maintenance HD for >3 months were included in this study. Pittsburgh Sleep Quality Index (PSQI) was used to measure individual’s sleep quality. Based on the global PSQI score, patients were divided into groups of good sleepers (PSQI < 5) and bad sleepers (PSQI ≥ 5). Results. Twenty-three patients (20.2%) were classified as good sleepers and 91 patients (79.8%) were bad sleepers. Bad sleepers have significantly higher serum hsCRP level and lower serum phosphate level (all P < 0.05). The global PSQI score, or worse sleep quality are positively correlated with serum triglyceride level, high-sensitivity C-reactive protein(hsCRP)level,IL-1βlevelandnegativelycorrelated with the haemoglobin and phosphate level. In the multivariable linear regression model, levels of hsCRP (β = 0.209, P = 0.029) and triglyceride (β = 0.212, P = 0.025) were both significant independent predictors for the global PSQI score. Conclusion. Our study demonstrated severe impairment of sleep quality in HD patients and corroborated the role of inflammation in the pathogenesis of sleep disturbance.

Background/Aims: Pentoxifylline (PTX) has been shown to inhibit renal inflammation in a rat model of crescentic glomerulonephritis. The present study investigated the role of PTX in renal fibrosis in rats with crescentic glomerulonephritis. Methods: A rat model of accelerated anti-glomerular basement membrane glomerulonephritis was induced and treated with PTX or vehicle control for 3, 7, 14 and 28 days. The therapeutic effect and mechanism of PTX on renal fibrosis were examined by Northern blot and immunohistochemistry. Results: Diseased rats treated with vehicle control developed a severe crescentic glomerulonephritis with progressive renal fibrosis identified by a marked accumulation of α-SMA+ myofibroblasts and collagen matrix. This was associated with tubular epithelial-myofibroblast transition as evident by de novo expression of α-SMA and a loss of E-cadherin on damaged tubular epithelial cells. Further studies revealed that severe renal fibrosis was associated with upregulation of renal TGF-β1 and activation of TGF-β/Smad signaling, which was blocked by treatment with PTX. Conclusions: PTX may be an anti-fibrosis agent capable of inhibiting renal fibrosis in a rat model of crescentic glomerulonephritis. Blockade of TGF-β1 expression and Smad2/3 activation may be a mechanism by which PTX inhibits renal fibrosis.

The peritoneum is subject to alterations in the life-long course of peritoneal dialysis (PD). Studies of the parietal peritoneum by non-invasive ultrasonography in PD patients are limited. We hypothesize that a prolonged PD duration is associated with a thicker peritoneum on ultrasonography and alterations in Doppler indexes of mesenteric vessels.We recruited two groups of patients, 18 who had7 years of PD and 18 who had12 months of PD. We excluded patients with active peritonitis, history of major abdominal surgery, cirrhosis or malignancy. We measured the sonographic thickness of the parietal peritoneum and Doppler indexes of mesenteric vessels by trans-abdominal ultrasonography at two PD units in Taiwan.We found no significant difference between two groups of PD patients in peritoneal thickness and in Doppler indexes. However, our univariate and multivariate analysis indicated that peritoneal thickness is associated with peritoneal transport characteristics (dialysate/plasma creatinine) but not with age, duration of dialysis, body height, body weight or Doppler index. The peritoneum is significantly thicker in rapid transporters than in slow transporters (RUQ: 0.59 +/- 0.40 mm versus 0.27 +/- 0.29 mm, P = 0.01; LUQ: 0.60 +/- 0.40 mm versus 0.27 +/- 0.32 mm, P = 0.016; LQ: 1.07 +/- 0.85 mm versus 0.48 +/- 0.53 mm, P = 0.026). In addition, rapid transporters have a marginally lower Doppler resistive index of the superior mesenteric artery (0.87 +/- 0.08 versus 0.90 +/- 0.10, P = 0.028).Our data showed that peritoneal thickening is not inevitable in long-term PD patients. Sonographic thickness in the parietal peritoneum is associated with transport characteristics. Rapid transporters have a significantly thicker peritoneum. The Doppler index of mesenteric vessels had no association with PD duration or transport characteristics. Trans-abdominal ultrasonography is non-invasive and useful in evaluating peritoneal characteristics of PD patients.

This study aimed to study the effect of bradykinin on reactive oxygen species (ROS) generation, mitochondrial injury, and cell death induced by ATP depletion in cell culture. Renal tubular cells were subjected to ATP depletion. Cell death was evaluated with LDH release, sub-G0/G1 fraction, Hoechst staining, and annexin V binding assay. ROS generation, mitochondrial membrane potential (DeltaPsi(m)), and intramitochondrial calcium were evaluated with flow cytometry. Translocation of cytochrome c and activation of apoptotic protein were analyzed with cell fractionating and Western blotting. Intracellular calcium was measured with a spectrofluorometer. Bradykinin enhanced cellular LDH release, apoptosis, generation of superoxide, and hydrogen peroxide induced by ATP depletion. Bradykinin also enhanced the loss of DeltaPsi(m), translocation of cytochrome c into cytosol, and activation of apoptotic protein. The intracellular/mitochondrial calcium was higher in bradykinin-treated cells. All these effects were reversed by coadministration with bradykinin B2 receptor (B2R) antagonist. Besides, blocking the phospholipase C (PLC) could reverse the synergistic effect of bradykinin with ATP depletion on ROS generation, mitochondrial damage, accumulation of intracellular/mitochondrial calcium, and apoptosis. Activation of B2R aggravates ROS generation, mitochondrial damage, and cell death induced by ATP depletion. These effects may act through the PLC-Ca(2+) signaling pathway.

Background The prevalence of sexual dysfunction among male haemodialysis patients is high. Sexual dysfunction is composed of both physiological and psychological factors. However, the role of psychological depression is still obscure. Methods A multicentre cross-sectional study of 411 male haemodialysis patients was conducted to define the determinants of sexual dysfunction. Mid-week pre-dialytic biochemical and haematological parameters were obtained. All patients were required to complete three questionnaires by themselves: (i) the International Index of Erectile Function (IIEF, Chinese version); (ii) the Beck Depression Inventory (BDI, Chinese version) and (iii) the 36-item Short Form Health Survey Questionnaire (SF-36, Taiwan Standard Version 1.0). Results In total, 154 male patients completed the IIEF questionnaire. Their mean age was 50.2 +/- 10.7 years. A linear multivariable regression analysis demonstrated advanced age, diabetes and the presence of depressive symptoms to be independently associated with sexual dysfunction. Subjects with sexual dysfunction had significantly lower quality of life scores. Conclusions The presence of depressive symptoms, highly prevalent in haemodialysis patients, is an independent factor of sexual dysfunction in male haemodialysis patients. In a comprehensive approach to the management of sexual dysfunction, a thorough evaluation of psychological depression must be included.

The purpose of pulse analysis system is to provide a platform for researchers to analyze, share, and store patients' pulse data. Researchers can use the system to extract features through Fast Fourier Transform (FFT), harmonics, Ensemble Empirical Mode Decomposition (EEMD), and then take advantage of the former result to gather statistics and classify patients through two-sample t-test or paired-sample t-test. A group of researchers working in National Taiwan University Hospital (NTUH) have done an experiment to examine whether to find out acute kidney injury (AKI) through this system is feasible. The experimental subjects were patients who received open heart surgery. The experiment result shows that after surgery the mean value of harmonic 2 and 3 of patients with postoperative AKI from the proposed pulse analysis system decreased significantly, but not in patients without AKI. This system may have a potential for clinical use to detect AKI after open heart surgery and probably other disease. However, we need more cases to verify this experiment result because the number of AKI patients is limited.

The kallikrein/kinin system is beneficial in ischemia/reperfusion injury in heart, controversial in brain, but detrimental in lung, liver, and intestine. We examined the role of the kallikrein/kinin system in acute ischemia/reperfusion renal injury induced by 40 min occlusion of the renal artery followed by reperfusion. Rats were infused with tissue kallikrein protein 5 days before (pretreated group) or after (treated group) ischemia. Two days later, the pretreated group exhibited the worst renal dysfunction, followed by the treated group, then the control group. Kallikrein increased tubular necrosis and inflammatory cell infiltration with generation of more tumor necrosis factor-alpha and monocyte chemoattractant protein-1. Reactive oxygen species (ROS), malondialdehyde, and reduced/oxidized glutathione measurement revealed that the oxidative stress was augmented by kallikrein administration in both ischemic and reperfusion phases. The groups with more ROS generation also had more apoptotic renal cells. The deleterious effects of kallikrein on ischemia/reperfusion injury were reversed by cotreatment with bradykinin B2 receptor (B2R) antagonist, but not B1 receptor antagonist, and were not associated with hemodynamic changes. We conclude that early activation of B2R augmented ROS generation in ischemia/reperfusion renal injury, resulting in subsequent apoptosis, inflammation, and tissue damage. This finding suggests the potential application of B2R antagonists in acute ischemic renal disease associated with bradykinin activation.

Background. After long-term treatment with continuous ambulatory peritoneal dialysis (CAPD), some patients may develop peritoneal fibrosis. Peritoneal mesothelial cells (PMCs) participate in the inflammatory reactions in the peritoneal cavity, and transforming growth factor-b1 (TGF-b1) and interleukin-1b (IL-1b) are involved in peritoneal fibrosis. Diltiazem is used frequently in patients with CAPD to treat hypertension. The objectives of this study were to examine the effects of diltiazem on collagen- and IL-1b-induced TGF-b1 production on human PMCs and the signalling pathway of diltiazem in this induction. Methods. Human PMCs were cultured from the enzymatic disaggregation of human omentum. Collagen synthesis was measured by [ 3 H]proline incorporation into pepsin-resistant, salt-precipitated collagen. The expression of collagen I and III, and TGF-b1 mRNA was evaluated by northern blotting. The production of TGF-b1 by human PMCs was measured by immunoassay. The changes of intracellular calcium level after adding Fura-2-AM were measured by fluorescence spectrophotometry. Western blotting was used to assess mitogen-activated protein kinase (MAPK) signalling proteins. Results. We found that diltiazem (

Background/Purpose: Pauci-immune glomerulonephritis (GN) is an important cause of crescentic GN, acute renal failure and mortality. However, data are limited on the clinical presentation and outcome in antineutrophil cytoplasmic antibody (ANCA) negative patients, especially in Asians. Methods: This retrospective study analyzed medical records and pathology slides of patients who received renal biopsy between February 1998 and October 2004. Enzyme-linked immunosorbent assay was used routinely for ANCA testing in all patients. Results: Among 637 patients with biopsy-proven GN included in this study, 88 (13.8%) had glomerular crescent formation. Among them, pauci-immune crescentic glomerulonephritis (PICGN) (42 patients, 47.2%) and lupus nephritis (25 patients, 28.4%) were the most common pathologic diagnoses. Lupus patients were younger (p=0.028), while PICGN patients had more chronic lesions (p＜0.001), extensive glomerular crescents (p＜0.001), less severe proteinuria (p＜0.001) and poorer renal survival (p=0.0017). Among the PICGN patients, 62.5% had a positive ANCA test, 80% had myeloperoxidase-ANCA and 20% had proteinase-3-ANCA. Subgroup analysis showed that ANCA negativity was associated with less crescent formation (p＜0.001) but more chronic glomerular lesions (p＜0.001) and a trend toward worse renal outcome (p=0.055). Conclusion: This study illustrates the necessity for pathologic diagnosis of pauci-immune GN despite ANCA negativity. The poor prognosis associated with ANCA negativity in this study may be partly due to delayed diagnosis since these patients frequently lacked systemic involvement.

Background/Aims: This study investigated changes of interleukin-18 (IL-18) levels before and after dialysis, and the possible association with other pro-inflammatory cytokines, such as interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α). Methods: Plasma IL-18 of healthy controls, and pre- and post-dialysis of uremic patients undergoing hemodialysis (HD) were evaluated by ELISA methodology. Results: Plasma IL-18 levels were significantly increased in patients with maintenance HD (p Conclusion: Plasma IL-18 concentration was significantly higher in HD patients and was significantly elevated by cellulose-based HD processes. Pre-activation of immunologically active cells may contribute to the association between pre-dialysis IL-18 and post-dialysis IL-6 and TNF-α levels.

Peritoneal dialysis (PD) has been established as a main renal replacement therapy for approximately 20 years. However, long-term peritoneal exposure to high glucose and other unphysiologic contents in the PD solution may potentiate the development of peritoneal fibrosing syndrome (PFS) in PD patients. PFS is composed of a wide spectrum of peritoneal alterations, which has been observed in PD patients. Molecular studies have shown that the fibrogenic effect of peritoneal mesothelial cells and the accompanying accumulation of extracellular matrix in the peritoneum are key events leading to PFS. In this review, we highlight the impact of PFS and its pathogenetic factors, including bioincompatible PD solution, multidisciplinary inflammatory mediators, and stimulatory cytokines in the peritoneal cavity. Current therapeutic strategies based on both clinical and basic evidence for the prevention or treatment of PFS are also reviewed.

Sexual dysfunction in female hemodialysis patients: A multicenter study. Background Sexual function is one aspect of physical functioning. Sexual dysfunction, no matter the etiology, could cause distress. In female hemodialysis patients, sexual problems have often been neglected in clinical performance and research. Methods We conducted this study by use of self-reported questionnaires. A total of 578 female hemodialysis patients in northern Taiwan were included in this study. Demographic data, comorbid diseases, medications in use, biochemical, and hematologic parameters were analyzed. All patients were asked to complete by themselves three questionnaires: ( 1 ) the Index of Female Sexual Function (IFSF) to assess sexual function; ( 2 ) the Beck Depression Inventory (BDI) (Chinese version) to rate the severity of depressive symptoms; and ( 3 ) the 36-item Short Form Health Survey Questionnaire (SF-36, Taiwan Standard Version 1.0) to survey their quality of life. Results A total of 138 female patients were enrolled into further analysis. The mean age was 48.7 ± 11.2 years old. The mean IFSF score was 24.5 ± 9.3. Age, BDI score, and serum triglyceride levels were the independent factors of dysfunction in each sexual functional dimension. Patients with higher IFSF scores had significantly higher scores in physical functioning and mental health ( P = 0.007 and 0.018, respectively). Patients with higher intercourse satisfaction had significantly higher general health scores ( P = 0.001). Conclusion Sexual dysfunction is frequent in the female hemodialysis population. It is strongly associated with increasing age, dyslipidemia, and depression. The subjects with sexual dysfunction had poorer quality of life. The diagnosis and treatment of sexual dysfunction should be included in the clinical assessment.

A 63-year-old woman of South Asian origin, a Gujerati-speaking Hindu, was admitted 5 years ago to the renal unit at Leicester General Hospital for further evaluation of chronic kidney disease (CKD). She was born in India, moved to East Africa as a child, and migrated from Malawi to the United Kingdom in 1972. Her medical history included four uneventful pregnancies. She has no history of diabetes mellitus or hypertension. Three of her cousins had developed type 2 diabetes in the fourth decade of life, and her deceased aunt developed end-stage renal disease (ESRD) in the seventh decade of life and required renal replacement therapy (RRT). Three months before admission, the patient had reported increasing tiredness and was found to have a normochromic normocytic anemia, which was unresponsive to oral iron supplementation. On admission she reported continuing tiredness and breathlessness on moderate exertion, with no angina, cough, sputum, or wheeze. She reported nocturia for the previous 5 years but no other urinary symptoms. A review of systems was otherwise