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IntroductionPrevious studies in Ren-2 transgenic hypertensive rats (TGR) after 5/6 renal ablation (5/6 NX) have shown that besides pharmacological blockade of the renin-angiotensin system (RAS) also increasing kidney tissue epoxyeicosatrienoic acids (EET) levels by blocking soluble epoxide hydrolase (sEH), an enzyme responsible for degradation of EETs, and endothelin type A (ETA) receptor blockade retards chronic kidney disease (CKD) progression. This prompted us to evaluate if this progression will be alleviated by the addition of sEH inhibitor and ETA receptor antagonist to the standard complex blockade of RAS (angiotensin-converting enzyme inhibitor plus angiotensin II type 1 receptor blocker) in rats with established CKD.MethodsThe treatment regimens were initiated 6 weeks after 5/6 NX in TGR, and the follow-up period was 60 weeks.ResultsThe addition of sEH inhibition to RAS blockade improved survival rate, further reduced albuminuria and renal glomerular and kidney tubulointerstitial injury, and attenuated the decline in creatinine clearance - all this as compared with 5/6 NX TGR treated with RAS blockade alone. Addition of ETA receptor antagonist to the combined RAS and sEH blockade not only offered no additional renoprotection but, surprisingly, also abolished the beneficial effects of adding sEH inhibitor to the RAS blockade.ConclusionThese data indicate that pharmacological strategies that combine the blockade of RAS and sEH could be a novel tool to combat the progression of CKD. Any attempts to further extend this therapeutic regimen should be made with extreme caution.

Background: The dosing of aminoglycosides (AGs) in patients with kidney disease is challenging due to their markedly prolonged half-life, which renders pulse dosing schedules unsuitable. We performed a review of the literature that describes the pharmacokinetics of, and dosing recommendations for, AG for patients with abnormal renal functions and various renal replacement therapy modalities, focusing on patients treated with intermittent hemodialysis (iHD). Summary: During one iHD session, dialysis removes a remarkable amount of the drug regardless of the dialyzer type. In patients with severely reduced kidney functions, the distribution phase is prolonged, which needs to be taken into account when drawing samples shortly after drug administration or following an iHD session. Key Messages: The doses recommended for the pulse dosing of patients without kidney disease leads to unacceptably high overall systemic exposure for patients with severely reduced kidney functions even with dosing intervals extended up to 48 h. Therefore, lower doses accompanied by extended dosing intervals must be applied for this patient group. The clinical evidence and current recommendations support the dosing of AG following, rather than before, HD sessions. In patients with end-stage kidney disease, the samples for TDM of AGs should not be drawn earlier than 2 h after end of the infusion and 4 h after the end of iHD session to allow full (re)distribution of the drug.

Introduction: Acute tubulointerstitial nephritis (ATIN) is a well-recognized cause of acute kidney injury (AKI) due to the tubulointerstitial inflammation. The aim of this study was to explore the clinical features, outcomes, and responses to corticosteroid treatment in patients with ATIN. Methods: Patients with biopsy-proven ATIN, who were diagnosed between 1994 and 2016 at the Department of Nephrology, Charles University, First Faculty of Medicine, and General University Hospital in Prague, were included in the study. Patient demographics, the aetiological and clinical features, the treatment given, and the outcome at 1 year of follow-up were extracted from patient records. Results: A total of 103 ATIN patients were analysed, of which 68 had been treated with corticosteroids. There was no significant difference in the median serum creatinine 280 (169–569) µmol/L in the conservatively managed group versus 374 (249–558) µmol/L in the corticosteroid-treated group, p = 0.18, and dependence on dialysis treatment at baseline at the time of biopsy (10.3 vs. 8.6%). During the 1 year of follow-up, those ATIN patients who had been treated with corticosteroids did better and showed greater improvement in kidney function, determined as serum creatinine difference from baseline and from 1 month over 1-year period (p = 0.001). Conclusions: This single-centre retrospective cohort study supports the beneficial role of the administration of corticosteroid therapy in the management of ATIN.

Background/aimsWe found recently that increasing renal epoxyeicosatrienoic acids (EETs) levels by blocking soluble epoxide hydrolase (sEH), an enzyme responsible for EETs degradation, shows renoprotective actions and retards the progression of chronic kidney disease (CKD) in Ren-2 transgenic hypertensive rats (TGR) after 5/6 renal ablation (5/6 NX). This prompted us to examine if additional protection is provided when sEH inhibitor is added to the standard renin-angiotensin system (RAS) blockade, specifically in rats with established CKD.MethodsFor RAS blockade, an angiotensin-converting enzyme inhibitor along with an angiotensin II type receptor blocker was used. RAS blockade was compared to sEH inhibition added to the RAS blockade. Treatments were initiated 6 weeks after 5/6 NX in TGR and the follow-up period was 60 weeks.ResultsCombined RAS and sEH blockade exhibited additional positive impact on the rat survival rate, further reduced albuminuria, further reduced glomerular and tubulointerstitial injury, and attenuated the decline in creatinine clearance when compared to 5/6 NX TGR subjected to RAS blockade alone. These additional beneficial actions were associated with normalization of the intrarenal EETs deficient and a further reduction of urinary angiotensinogen excretion.ConclusionThis study provides evidence that addition of pharmacological inhibition of sEH to RAS blockade in 5/6 NX TGR enhances renoprotection and retards progression of CKD, notably, when applied at an advanced stage.

Introduction: Acute tubulointerstitial nephritis (ATIN) is a well-recognized cause of acute kidney injury (AKI) due to the tubulointerstitial inflammation. The aim of this study was to explore the clinical features, outcomes, and responses to corticosteroid treatment in patients with ATIN. Methods: Patients with biopsy-proven ATIN, who were diagnosed between 1994 and 2016 at the Department of Nephrology, Charles University, First Faculty of Medicine, and General University Hospital in Prague, were included in the study. Patient demographics, the aetiological and clinical features, the treatment given, and the outcome at 1 year of follow-up were extracted from patient records. Results: A total of 103 ATIN patients were analysed, of which 68 had been treated with corticosteroids. There was no significant difference in the median serum creatinine 280 (169–569) µmol/L in the conservatively managed group versus 374 (249–558) µmol/L in the corticosteroid-treated group, p = 0.18, and dependence on dialysis treatment at baseline at the time of biopsy (10.3 vs. 8.6%). During the 1 year of follow-up, those ATIN patients who had been treated with corticosteroids did better and showed greater improvement in kidney function, determined as serum creatinine difference from baseline and from 1 month over 1-year period (p = 0.001). Conclusions: This single-centre retrospective cohort study supports the beneficial role of the administration of corticosteroid therapy in the management of ATIN. [ABSTRACT FROM AUTHOR]

Background/Aims: Podocytes are typically cultured on collagen I; however, collagen I is absent from healthy glomerular basement membranes. Erythropoietin (EPO) is thought to protect podocytes in vivo. Here, we studied how various types of extracellular matrix (ECM) proteins and EPO affect podocytes in culture. Methods: Primary rat podocytes were replated on collagen I, collagen IV, whole ECM extract, laminin, or bare plastic. Cellular adhesion (8 hours after plating), proliferation (5 days, 10 % serum), and resistance to serum deprivation (3 days, 0.5 % serum) were assessed. BrdU incorporation and expression of podocyte-specific markers were employed as measures of cellular proliferation and differentiation, respectively. qPCR was used to verify expression of EPO receptor in cultured podocytes. Results: Cellular adhesion was similar on all ECM proteins and unaffected by EPO. Proliferation was accelerated by laminin and the ECM extract, but the final cell density was similar on all ECM surfaces. Collagen IV supported the serum-deprived cells better than the other ECM proteins. EPO (2-20 ng/ml) improved viability of serum-deprived podocytes on collagen I, collagen IV, and ECM, but not on laminin or bare plastic. The cells expressed mRNA for EPO receptor. Conclusion: The physiological ECM proteins are more supportive of primary podocytic cultures compared with collagen I. The protective effects of EPO during serum deprivation are modulated by the cultivation surface.

Background: The dosing of aminoglycosides (AGs) in patients with kidney disease is challenging due to their markedly prolonged half-life, which renders pulse dosing schedules unsuitable. We performed a review of the literature that describes the pharmacokinetics of, and dosing recommendations for, AG for patients with abnormal renal functions and various renal replacement therapy modalities, focusing on patients treated with intermittent hemodialysis (iHD). Summary: During one iHD session, dialysis removes a remarkable amount of the drug regardless of the dialyzer type. In patients with severely reduced kidney functions, the distribution phase is prolonged, which needs to be taken into account when drawing samples shortly after drug administration or following an iHD session. Key Messages: The doses recommended for the pulse dosing of patients without kidney disease leads to unacceptably high overall systemic exposure for patients with severely reduced kidney functions even with dosing intervals extended up to 48 h. Therefore, lower doses accompanied by extended dosing intervals must be applied for this patient group. The clinical evidence and current recommendations support the dosing of AG following, rather than before, HD sessions. In patients with end-stage kidney disease, the samples for TDM of AGs should not be drawn earlier than 2 h after end of the infusion and 4 h after the end of iHD session to allow full (re)distribution of the drug. [ABSTRACT FROM AUTHOR]

Introduction: Previous studies in Ren-2 transgenic hypertensive rats (TGR) after 5/6 renal ablation (5/6 NX) have shown that besides pharmacological blockade of the renin-angiotensin system (RAS) also increasing kidney tissue epoxyeicosatrienoic acids (EET) levels by blocking soluble epoxide hydrolase (sEH), an enzyme responsible for degradation of EETs, and endothelin type A (ETA) receptor blockade retards chronic kidney disease (CKD) progression. This prompted us to evaluate if this progression will be alleviated by the addition of sEH inhibitor and ETA receptor antagonist to the standard complex blockade of RAS (angiotensin-converting enzyme inhibitor plus angiotensin II type 1 receptor blocker) in rats with established CKD. Methods: The treatment regimens were initiated 6 weeks after 5/6 NX in TGR, and the follow-up period was 60 weeks. Results: The addition of sEH inhibition to RAS blockade improved survival rate, further reduced albuminuria and renal glomerular and kidney tubulointerstitial injury, and attenuated the decline in creatinine clearance – all this as compared with 5/6 NX TGR treated with RAS blockade alone. Addition of ETA receptor antagonist to the combined RAS and sEH blockade not only offered no additional renoprotection but, surprisingly, also abolished the beneficial effects of adding sEH inhibitor to the RAS blockade. Conclusion: These data indicate that pharmacological strategies that combine the blockade of RAS and sEH could be a novel tool to combat the progression of CKD. Any attempts to further extend this therapeutic regimen should be made with extreme caution. [ABSTRACT FROM AUTHOR]

Matrix metalloproteinases (MMPs) are endopeptidases within the metzincin protein family that not only cleave extracellular matrix (ECM) components, but also process the non-ECM molecules, including various growth factors and their binding proteins. MMPs participate in cell to ECM interactions, and MMPs are known to be involved in cell proliferation mechanisms and most probably apoptosis. These proteinases are grouped into six classes: collagenases, gelatinases, stromelysins, matrilysins, membrane type MMPs, and other MMPs. Various mechanisms regulate the activity of MMPs, inhibition by tissue inhibitors of metalloproteinases being the most important. In the kidney, intrinsic glomerular cells and tubular epithelial cells synthesize several MMPs. The measurement of circulating MMPs can provide valuable information in patients with kidney diseases. They play an important role in many renal diseases, both acute and chronic. This review attempts to summarize the current knowledge of MMPs in the kidney and discusses recent data from patient and animal studies with reference to specific diseases. A better understanding of the MMPs' role in renal remodeling may open the way to new interventions favoring deleterious renal changes in a number of kidney diseases. [ABSTRACT FROM AUTHOR]

Background/Aims: We found recently that increasing renal epoxyeicosatrienoic acids (EETs) levels by blocking soluble epoxide hydrolase (sEH), an enzyme responsible for EETs degradation, shows renoprotective actions and retards the progression of chronic kidney disease (CKD) in Ren-2 transgenic hypertensive rats (TGR) after 5/6 renal ablation (5/6 NX). This prompted us to examine if additional protection is provided when sEH inhibitor is added to the standard renin-angiotensin system (RAS) blockade, specifically in rats with established CKD. Methods: For RAS blockade, an angiotensin-converting enzyme inhibitor along with an angiotensin II type receptor blocker was used. RAS blockade was compared to sEH inhibition added to the RAS blockade. Treatments were initiated 6 weeks after 5/6 NX in TGR and the follow-up period was 60 weeks. Results: Combined RAS and sEH blockade exhibited additional positive impact on the rat survival rate, further reduced albuminuria, further reduced glomerular and tubulointerstitial injury, and attenuated the decline in creatinine clearance when compared to 5/6 NX TGR subjected to RAS blockade alone. These additional beneficial actions were associated with normalization of the intrarenal EETs deficient and a further reduction of urinary angiotensinogen excretion. Conclusion: This study provides evidence that addition of pharmacological inhibition of sEH to RAS blockade in 5/6 NX TGR enhances renoprotection and retards progression of CKD, notably, when applied at an advanced stage. [ABSTRACT FROM AUTHOR]

Background: Pregnancy-associated plasma protein A (PAPP-A) is associated with adverse outcome of long-term hemodialysis patients (HD). The aim of the study was to test whether its homolog pregnancy-associated plasma protein A2 (PAPP-A2) can be detected in serum of HD patients and to define its significance. Methods: The studied group consisted of 102 long-term HD patients and 25 healthy controls. HD patients were prospectively followed up for five years (2009-2014). PAPP-A2 was measured by surface plasmon resonance biosensor, PAPP-A by time resolved amplified cryptate emission. Results: PAPP-A2, similarly as PAPP-A, was significantly increased in HD patients (median (interquartile range)) PAPP-A2: 6.2 (2.6- 10.8) ng/mL, vs. 3.0 (0.7-5.9) ng/mL, p=0.006; PAPP-A: 18.9 (14.3-23.4) mIU/L, vs. 9.5 (8.4-10.5) mIU/L, p<0.001). In HD patients, PAPP-A2 correlated weakly but significantly with PAPP-A (τ=0.193, p=0.004). Unlike PAPP-A, PAPP-A2 was not significant for prognosis of HD patients when tested alone. There was a significant interaction between PAPP-A and PAPP-A2 on the mortality due to infection of HD patients (p=0.008). If PAPP-A was below median, mortality due to infection was significantly higher for patients with PAPP-A2 values above median than for patients with low PAPP-A2 levels (p=0.011). Conclusion: PAPP-A2 is increased in HD patients and interacts with PAPP-A on patient's prognosis. [ABSTRACT FROM AUTHOR]

Background/Aims: Podocytes are typically cultured on collagen I; however, collagen I is absent from healthy glomerular basement membranes. Erythropoietin (EPO) is thought to protect podocytes in vivo. Here, we studied how various types of extracellular matrix (ECM) proteins and EPO affect podocytes in culture. Methods: Primary rat podocytes were replated on collagen I, collagen IV, whole ECM extract, laminin, or bare plastic. Cellular adhesion (8 hours after plating), proliferation (5 days, 10 % serum), and resistance to serum deprivation (3 days, 0.5 % serum) were assessed. BrdU incorporation and expression of podocyte-specific markers were employed as measures of cellular proliferation and differentiation, respectively. qPCR was used to verify expression of EPO receptor in cultured podocytes. Results: Cellular adhesion was similar on all ECM proteins and unaffected by EPO. Proliferation was accelerated by laminin and the ECM extract, but the final cell density was similar on all ECM surfaces. Collagen IV supported the serum-deprived cells better than the other ECM proteins. EPO (2-20 ng/ml) improved viability of serum-deprived podocytes on collagen I, collagen IV, and ECM, but not on laminin or bare plastic. The cells expressed mRNA for EPO receptor. Conclusion: The physiological ECM proteins are more supportive of primary podocytic cultures compared with collagen I. The protective effects of EPO during serum deprivation are modulated by the cultivation surface. © 2014 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Our previous studies in rats with ablation nephrectomy have shown similar cardiorenal protective effects of renin-angiotensin system (RAS)-dependent treatment (combination of angiotensin-converting enzyme inhibitor and angiotensin II receptor blocker) and RAS-independent treatment (combination of α- and β-adrenoreceptor antagonist and diuretics). Moreover, selective blockade of endothelin (ET) receptor type A (ETA) improved survival rate and attenuated hypertension and organ damage in Ren-2 transgenic rats. Therefore, we were interested in whether ETA receptor blockade could have additive effects to the classical blockade of the RAS. Transgenic rats underwent 5/6 renal ablation at the age of 2 months and were treated for 20 weeks with RAS blockers alone (angiotensin II receptor blocker - losartan, and angiotensin-converting enzyme inhibitor - trandolapril), ETA receptor blocker alone (atrasentan) or with the combination of RAS and ETA receptor blockade. RAS blockade normalized blood pressure and improved survival. It decreased cardiac hypertrophy and proteinuria as well as tissue angiotensin II and ET-1 levels. In contrast, ETA receptor blockade only partially improved survival rate, reduced blood pressure, attenuated the development of cardiac hypertrophy and transiently reduced proteinuria. However, no additive cardio- and renoprotective effects of ETA and RAS blockade were noted at the end of the study. Copyright © 2012 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Background/Aims: Pregnancy-associated plasma protein A (PAPP-A) is a biomarker related to vascular damage. The aim of the study was to focus on PAPP-A and related parameters and their relationship to the prognosis of long-term hemodialysis (HD) patients. Methods: This is a prospective observational cohort study which included 261 long-term HD patients followed up for 5 years and 66 healthy subjects. PAPP-A, placental growth factor (PlGF), matrix metalloproteinase 2 and 9 (MMP-2, MMP-9), insulin-like growth factor 1 (IGF-1), insulin-like growth factor binding protein-4 (IGFBP-4), and cardiac, nutritional and inflammatory parameters were measured at the beginning of the study and tested as predictors of mortality. Results: PAPP-A, PlGF, IGF-1, IGFBP-4 and MMP-2 were significantly increased in HD patients compared to controls (PAPP-A 27.6 ± 15.5 mIU/l in HD vs. 9.4 ± 2.5 mIU/l in controls, p < 0.001). Increased PAPP-A was a significant independent predictor of overall mortality and mortality due to infection in the multivariate Cox analysis [HR (95% CI): 1.237 (1.060-1.444), p = 0.007, and 1.416 (1.115-1.798), p = 0.004, per standard deviation, respectively]. PAPP-A was not related to cardiovascular mortality. Conclusion: Increased PAPP-A is a significant independent predictor of overall mortality and mortality due to infection but it was not related to cardiovascular mortality in this study. Copyright © 2011 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Background: The calcium-binding protein S100A12 (EN-RAGE) causes inflammation through interaction with the multiligand receptor for advanced glycation end products (RAGE). The aim of the study was to determine S100A12 levels and describe their relationship to inflammatory markers in patients with decreased renal function. Methods: The studied group consisted of 46 patients with various degrees of chronic renal insufficiency (CHRI), 31 long-term hemodialysis (HD) patients and 24 healthy controls. S100A12 and soluble RAGE were assessed immunochemically (ELISA), and routine biochemical parameters were measured. Results: S100A12 levels were not different in CHRI (166 ± 140 ng/ml) and HD patients (127 ± 101 ng/ml) compared to controls (126 ± 106 ng/ml; p = 0.20, n.s.). In CHRI patients, S100A12 correlated with C-reactive protein (CRP) levels, orosomucoid, and inversely with α2-macroglobulin. In HD patients, S100A12 correlated with age, CRP, orosomucoid, fibrinogen and leukocyte levels. In multivariate regression analysis after adjustment for age, S100A12 levels remained correlated with: orosomucoid in CHRI patients; CRP, leukocytes, fibrinogen and negatively with sRAGE in HD patients; and leukocytes in controls. Conclusions: Although S100A12 levels were not elevated in patients with decreased kidney function, a relation to markers of inflammation was found. Further studies are required to demonstrate the significance of S100A12 in patients with decreased renal function. Copyright © 2011 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Background: Advanced glycation end products (AGEs) belong to uremic toxins and some pathological effects of AGEs are linked to RAGE (receptor for AGEs). Their precursors are detoxified by the glyoxalase (GLO) system. The A419C (E111A) polymorphism of the GLO I gene is associated with vascular disease in hemodialysis (HD) patients and some RAGE gene polymorphisms are implicated in various pathological states. Aim: To study the relationship of A419C GLO I and four RAGE polymorphisms (–429T/C, –374T/A, 2184A/G and Gly82Ser) in the prognosis of HD patients. Methods: The group studied consisted of 214 chronic HD patients prospectively followed up for 43 months. 100 patients died, 48 due to cardiovascular causes. Results: The Kaplan-Meier analysis showed a higher mortality rate in patient-mutated homozygotes for RAGE –429CC, RAGE 2184GG and GLO I 419CC. A higher hazard risk was confirmed by the Cox proportional hazards model when wild-type homozygotes were taken as reference: RAGE –429CC 2.28 (95% CI 1.04–4.99), RAGE 2184GG 3.16 (95% CI 1.44–6.93), and GLO I 419CC 1.75 (95% CI 1.08–2.86). Both RAGE polymorphisms were also associated with cardiovascular mortality: RAGE –429CC 3.54 (95% CI 1.37–9.14) and RAGE 2184GG 5.04 (95% CI 1.93–13.11). Conclusion: In summary, our study shows for the first time a link between RAGE and GLO polymorphisms in the prognosis of HD patients. Copyright © 2010 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Background: High cardiovascular risk in patients with chronic kidney disease (CKD) may be related to mineral disorder and microinflammation. Fibroblast growth factor 23 (FGF-23) is a phosphatonin and inhibitor of calcitriol synthesis, which is associated with poor prognosis in CKD patients starting dialysis. Matrix-metalloproteinases (MMP-2, MMP-9) contribute to myocardial remodeling and arterial calcification. FGF-23 and MMPs levels are altered in CKD, however, little is known about their association and relation to cardiovascular (CV) disease. Methods: Standard laboratory parameters, plasma levels of MMP-2, MMP-9, FGF-23, PAPP-A and CV disease history were assessed in 80 patients with CKD 1–5 and 44 healthy control subjects. Results: FGF-23 and MMP-2 (assessed by ELISA) were higher in CKD patients compared to controls. FGF-23 increased from CKD 3, whereas MMP-2 increased only in CKD 5. FGF-23 was positively associated with MMP-2, adjusted to age, eGFR, phosphatemia, calcitriol and parathormone. FGF-23 independently correlated with parathormone and inversely with calcitriol, whereas MMP-2 was related to phosphatemia. FGF-23 was higher in subjects with a history of CV disease compared to those free of such history (559.0 vs.184.0 RU/ml), adjusted to age and eGFR. Conclusion: Our data suggest a possible relationship between FGF-23, MMP-2 and CV disease in CKD. Potential causality of this association remains to be elucidated. Copyright © 2009 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Background: Significant phenotypical variability is observed in autosomal dominant polycystic kidney disease (ADPKD). Dysregulation of vascular endothelial growth factor (VEGF) expression in the kidney has been demonstrated in a wide range of renal diseases. The aim of the present study was to assess the influence of the –2578 C/A and the –1154 G/A polymorphisms in the regulatory region of the VEGF gene upon the progression of ADPKD toward end-stage renal disease (ESRD). Methods: The study was performed on 283 ADPKD patients (145 males, 138 females, mean age 51.7 ± 10.3 years) who had reached ESRD. Patients were divided into three groups: (1) ESRD development later than in 63 years (slow progressors, n = 47), (2) ESRD development before 45 years (rapid progressors, n = 69), and (3) ESRD development between 45 and 63 years (intermediate progressors, n = 167). Genetically unrelated healthy Czech individuals were analyzed as a control group (n = 311, 153 males, 158 females, mean age 44.6 ± 9.2 years). DNA samples were genotyped for the –2578 C/A and for the –1154 G/A polymorphisms of the VEGF gene promoter. The serum levels of VEGF were established in 111 healthy Czech individuals from the control group. Results: The VEGF –2578 C/A and –1154 G/A genotype distribution showed no differences among the groups of slow, rapid and intermediate progressors. The age of ESRD with regard to different genotypes was not significantly different in all ADPKD patients. However, the AA genotype of the –2578 C/A polymorphism was associated with a significantly higher age of ESRD than other genotypes in rapid progressors (42.7 vs. 40.5 years, p = 0.01). The CG haplotype was found significantly more frequent in ADPKD rapid progressors than in slow progressors (p = 0.047). Serum levels of VEGF did not significantly differ in the control group, according to different genotypes of both polymorphisms. Conclusion: To conclude, AA genotype of the –2578 C/A polymorphism was related to better prognosis of the disease in a limited group of ADPKD patients. Classical genetic recessive and dominant model did not find significant influence of separate VEGF polymorphisms on the progression of ADPKD. Accordingly, CG haplotype was associated with earlier onset of ESRD in ADPKD patients. Copyright © 2008 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Background/Aims: Bone marrow-derived endothelial progenitor cells (EPCs) are believed to contribute to endothelial repair after vascular damage. To investigate the potential for microvascular repair in patients with ANCA-associated vasculitis (AAV), we conducted a cross-sectional study determining the number of circulating EPCs in patients with AAV, chronic uremia, atherosclerosis, and in healthy volunteers. Methods: The number of circulating EPCs was determined by colony-forming assay in 41 patients with AAV, 15 hemodialysis patients (without vasculitis), 13 patients with peripheral arterial occlusive disease (PAOD), and 25 healthy controls. Results: Patients with AAV had a significantly lower number of CFU-Hill than healthy subjects (median 0.3 vs. 19.5 CFU-Hill/ml blood, p < 0.0001), but not than patients on hemodialysis or with PAOD. Neither institution of treatment nor entering remission increased the number of EPCs in AAV patients. The number of EPCs did not correlate with markers of disease activity. AAV patients with glomerular filtration rate <15 ml/min had an even lower number of circulating EPCs than patients with better preserved renal function (median 0.05 vs. 1.2 CFU-Hill/ml, p = 0.015) and patients with anti-MPO positivity had a trend towards a higher number of EPCs than patients with anti-PR3 antibodies (median 3.1 vs. 0.18 CFU-Hill/ml, p = 0.06). Conclusion: Patients with AAV have a significant and persistent deficiency of circulating EPCs. A low number of EPCs could reflect an impaired mechanism of vascular repair and may contribute to repeated relapses in these patients. Copyright © 2008 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Background: The present study was performed in hypertensive Ren-2 transgenic rats (TGR) and in normotensive Hannover Sprague-Dawley (HanSD) rats. First, the intrarenal protein expression of CYP4A, the enzyme catalyzing the formation of 20-hydroxyeicosatetraenoic acid (20-HETE), and of CYP2C23, the enzyme responsible for epoxyeicosatrienoic acid (EET) production, was evaluated. Second, the renal functional responses to inhibition of the intrarenal formation of 20-HETE and EETs were investigated. Methods: Renal hemodynamics and electrolyte excretion were evaluated in response to the administration of inhibitors of 20-HETE and EET formation into the renal artery. In renal cortical tissue, CYP4A and CYP2C23 protein expression was assessed by Western blot analysis. Urinary concentrations of 20-HETE and EETs were measured using a fluorescent HPLC assay. Results: TGR have higher kidney CYP4A protein expression and urinary 20-HETE excretion but significantly lower CYP2C23 protein expression and urinary EET excretion than HanSD. Intrarenal inhibition of 20-HETE and EET formation decreased sodium excretion in HanSD, whereas inhibition of 20-HETE increased urinary excretion of sodium in TGR without altering renal hemodynamics. Conclusions: Our data suggest that in TGR, deficient intrarenal synthesis of EETs combined with increased synthesis of 20-HETE with its stimulation of tubular sodium absorption may contribute to the development of hypertension in TGR. Copyright © 2007 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

The article discusses the relationship between biosimilars and its use in renal health care in Central and Eastern Europe (CEE). The economic development of CEE countries resulted to the increase in dialysis facilities. However, different standard of treatment using erythropoietin-stimulating agents still persists despite the increasing availability of dialysis treatment. Economic constraints contributed to the difference standard in the treatment of anemia in patients with chronic renal failure from CEE countries.

Podocytes (glomerular visceral epithelial cells) cover the exterior surface of the glomerular capillaries and contribute to the glomerular filtration membrane. Failure of podocyte function is involved in the progression of chronic glomerular disease; accordingly, research interest into podocyte biology is driven by the need for better protection and perhaps recovery of these cells in renal diseases. This review aims at summarizing available techniques for podocyte cell cultures from both the past and present, with special attention to the currently used methods. The establishment of classical primary cultures is based on isolation of glomeruli by differential sieving. Plating of glomeruli onto a collagen surface is followed by an outgrowth of cobblestone-like cells that, after replating, differentiate into arborized, mature podocytes. Currently, the majority of research studies use immortalized podocytic cell lines most often derived from transgenic mice bearing a conditional immortalizing gene. The podocytes can also be collected and cultured from healthy or diseased animal or patient urine. The urinary podocytes obtained from subjects with active glomerulopathies display higher proliferation potential and viability in vitro, perhaps due to disease-induced transdifferentiation. Finally, a list of phenotypic markers useful for identification and characterization of the cultured podocytic elements is provided. Copyright © 2007 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Background: The aim of the study was to assess the contribution of carbonyl and oxidative stresses to the development of amyloidosis in patients suffering from chronic rheumatic diseases, and the potential influence of renal function to their concentrations was considered. Methods: We investigated 17 patients with chronic rheumatological diseases and histologically proven diagnosis of AA amyloidosis (group AA-RA), 26 patients suffering from rheumatoid arthritis without any signs of AA amyloidosis (group nonAA-RA) and 20 healthy volunteers (Co). In all patients, advanced glycation end products (AGEs), advanced oxidation protein products (AOPP), pregnancy-associated plasma protein A (PAPP-A) and other selected proinflammatory markers were measured. Results: An increase in serum levels of AOPP and AGEs was found in the AA-RA group in comparison with nonAA-RA patients and also with Co (p < 0.001 for all comparisons). AGEs positively correlated with serum creatinine (r = 0.67, p = 0.004) and negatively with glomerular filtration rate (r = –0.54, p = 0.027). We did not find a correlation between AOPP and any other assessed parameters including proteins and renal parameters. PAPP-A levels were not significantly increased in any group of patients (AA-RA, nonAA-RA) in comparison with Co. Conclusions: Increased plasma levels of AGEs and AOPP in the group of patients with AA-RA may have been partly explained by the diminished renal clearance. However, the increase in AOPP levels was higher than what is expected in this degree of renal failure (glomerular filtration rate in the AA-RA group corresponding to chronic kidney disease stage III). Copyright © 2007 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Background/Aims: A growing body of evidence suggests that the interplay between the endothelin (ET) and the renin-angiotensin systems (RAS) plays an important role in the development of the malignant phase of hypertension. The present study was performed to evaluate the role of an interaction between ET and RAS in the development of hypertension and hypertension-associated end-organ damage in homozygous male transgenic rats harboring the mouse Ren-2 renin gene (TGRs) under conditions of normal-salt (NS, 0.45% NaCl) and high-salt (HS, 2% NaCl) intake. Methods: Twenty-eight-day-old homozygous male TGRs and age-matched transgene-negative male normotensive Hannover Sprague-Dawley (HanSD) rats were randomly assigned to groups with NS or HS intake. Nonselective ETA/B receptor blockade was achieved with bosentan (100 mg/kg/day). Systolic blood pressure (BP) was measured in conscious animals by tail plethysmography. Rats were placed into metabolic cages to determine proteinuria and clearance of endogenous creatinine. At the end of the experiment the final arterial BP was measured directly in anesthetized rats. Kidneys were taken for morphological examination. Results: All male HanSD fed either the NS or HS diet exhibited a 100% survival rate until 180 days of age (end of experiment). The survival rate in untreated homozygous male TGRs fed the NS diet was 41%, which was markedly improved by treatment with bosentan to 88%. The HS diet reduced the survival rate in homozygous male TGRs to 10%. The survival rate in homozygous male TGRs on the HS diet was significantly improved by bosentan to 69%. Treatment with bosentan did not influence either the course of hypertension or the final levels of BP in any of the experimental groups of HanSD rats or TGRs. Although the ET-1 content in the renal cortex did not differ between HanSD rats and TGRs, ET-1 in the left heart ventricle of TGRs fed the HS diet was significantly higher compared with all other groups. Administration of bosentan to homozygous male TGRs fed either the NS or HS diet markedly reduced proteinuria, glomerulosclerosis and attenuated the development of cardiac hypertrophy compared with untreated TGR. Conclusions: Our data show that nonselective ETA/B receptor blockade markedly improves the survival rate and ameliorates end-organ damage in homozygous male TGRs without significantly lowering BP.Copyright © 2004 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Background: The aim of the study was to determine pregnancy-associated plasma protein-A (PAPP-A), which was recently described as a new marker of cardiovascular events, in patients with chronic renal insufficiency/ failure and to find out its relationship to renal function and to prominent markers of oxidative stress (advanced oxidation protein products -- AOPP) and inflammation (C-reactive protein -- CRP). Methods: The studied group consisted of 36 chronic hemodialysis patients (HD), 10 patients treated with continuous ambulatory peritoneal dialysis (CAPD) and 38 patients with chronic renal insufficiency (CHRI) not yet dialyzed. PAPP-A was measured by Time Resolved Amplified Cryptate Emission technology. Determination of AOPP is based on a spectrophotometric method. Results: PAPP-A levels are statistically significantly elevated in the both groups of dialyzed patients in comparison with healthy subjects (27.0 ± 16.5 mIU/l in HD and 14.07 ± 6.73 mIU/l in CAPD vs. 8.22 ± 2.7 mIU/l in the control group, p < 0.0001 and p < 0.001, respectively, p < 0.05 HD vs. CAPD). The mean serum PAPP-A levels in the CHRI patients not yet dialyzed were not significantly higher in comparison with the control group (9.72 ± 4.44 vs. 8.22 ± 2.7 mIU/l, n.s.). In the CHRI not dialyzed patients, we found a significant positive correlation between serum creatinine and PAPP-A levels (r = 0.68, p < 0.05). In comparison with controls, AOPP and CRP levels were significantly higher in HD patients [AOPP 155.0 ± 37.9 µmol/l, p < 0.0001 vs. controls, CRP 10.0 (4.6 - 26.9) mg/l (median, interquartile range), p < 0.0001 vs. controls], CAPD patients [AOPP 118.5 ± 25.8 µmol/l, p < 0.0001 vs. controls, CRP 7.7 (2.0-18.8) mg/l, p < 0.01 vs. controls] and AOPP levels in chronic renal failure patients not yet dialyzed (98.5 ± 43.24 µmol/l, p < 0.01 vs. controls). The correlations between PAPP-A and AOPP (r = 0.49, p < 0.05) and PAPP-A and CRP (r = 0.48, p < 0.05) serum concentration were statistically significant in HD patients. In CAPD patients, neither a correlation between PAPP-A and AOPP nor a correlation between PAPP-A and CRP were found. Conclusion: We can conclude that serum PAPP-A levels sensitively reflect the changes in renal function, depend on dialysis modality, and may represent a novel marker associated with inflammation and oxidative stress in chronic renal failure patients. [ABSTRACT FROM AUTHOR]

As a result of oxidative and carbonyl stress, advanced glycation end products (AGEs) are involved in the pathogenesis of severe and frequent diseases and their fatal vascular/cardiovascular complications, i.e. diabetes mellitus and its complications (nephropathy, angiopathy, neuropathy and retinopathy, renal failure and uremic and dialysis-associated complications), atherosclerosis and dialysis-related amyloidosis, neurodegenerative diseases, and rheumatoid arthritis. They are formed via non-enzymatic glycation which is specifically enhanced through the presence of oxidative and carbonyl stress, and their ability to form glycoxidation products in peptide and protein structures finally modulating or inducing biological reactivity. Food can be another source of AGEs; however, high serum AGEs in hemodialysis patients might reflect nutritional status better. Several methods of renal replacement therapy have been studied in connection with the AGE removal, but unfortunately the possibilities are still unsatisfactory even if high flux dialysis, hemofiltration, or hemodiafiltration give better results than conventional low flux dialysis. AGEs are currently being studied in the patients on peritoneal dialysis as their precursors can be formed in the dialysis fluid. AGEs can cause damage to the peritoneum and so a loss of ultrafiltration capacity. Many compounds give promising results in AGE inhibition (inhibition of formation of AGEs, inhibition of their action or degradation of AGEs), are tested for these properties, and eventually undergo clinical studies (e.g. aminoguanidine, OPB-9195, pyridoxamine, antioxidants, N-phenacylthiazolium bromide, antihypertensive drugs, angiotensin-converting enzyme inhibitors and angiotensin II receptor-1 antagonists). [ABSTRACT FROM AUTHOR]

AbstractBackground: A significant phenotypical variability is observed in autosomal dominant polycystic kidney disease (ADPKD). The variability can not be fully explained by the genetic heterogenity of the disease. We examined the influence of the ACE I/D polymorphism, adducin Trp460Gly polymorphism and the association of both polymorphisms on the progression of ADPKD towards end-stage renal failure (ESRF). Methods: 320 ADPKD patients (pts) were analyzed, 220 pts (113 males, 107 females) with ESRF before 63 years of age, with a subgroup (rapid progressors) of 20 pts (12 males, 8 females) with ESRF before 40 years of age, 52 pts (23 males, 29 females) with ESRF later than 63 years of age (slow progressors), 48 ADPKD pts (18 males, 30 females) with mean age ±50 years with serum creatinine <110 μmol/l (slow progressors) and 200 genetically unrelated healthy Czech subjects. DNA samples from collected blood were genotyped for the ACE I/D polymorphism and the Trp460Gly of α-adducin gene polymorphism. Results: The α-adducin genotypes showed no differences among the groups of slow progressors (74% Gly/Gly, 22.9% Gly/Trp and 3.1% Trp/Trp), pts with ESRF before 63 years of age (67.7% Gly/Gly, 30.5% Gly/Trp and 1.8% Trp/Trp) and rapid progressors (75% Gly/Gly, 25% Gly/Trp). The ACE genotypes did not differ among the groups of slow progressors (27.1% I/I, 44.8% I/D and 28.1% D/D), pts with ESRF before 63 years of age (23.6% I/I, 51.4% I/D and 25% D/D) and rapid progressors (20% I/I, 55% I/D and 25% D/D). The distribution did not differ from the control group. The ages of ESRF according to different genotypes did not significantly differ. We observed a significant tendency to better prognosis in Trp allele carriers for I/I genotype in comparison with Gly/Gly homozygous subjects. Conclusion: The ACE and α-adducin polymorphisms do not play a significant role in the progression of ADPKD to ESRF.Copyright © 2003 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

The article profiles Professor Otto Schück, one of the founders of the Czech Society of Nephrology who is celebrating his 80th birthday on August 26, 2006. His educational and career background is provided. The awards given to him are cited, including the Jan Brod Award and the Bruno Watshinger Award. Details of his research work, interests and contributions to nephrology are provided.

No abstract available [ABSTRACT FROM AUTHOR]

No abstract available Copyright © 2010 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

The article provides information on the Czech Society of Nephrology (CSN). The society was founded in 1958 and was headed by Jan Brod, one of the founders of the International Society of Nephrology. An overview of the history of nephrology in the Czech Republic is presented. Aside from its participation in renal health care and educational activities, CSN also awards research grants, co-organizes the Czech-German-Polish Symposia and is in charge of several national renal registries.

The article discusses various reports within the issue related to nephrology, including papers on the differences in the economic situation and renal health care across old and new member states of the European Union, the complexity of the biopharmaceutical production process and the risk of immunogenecity.

Deals with the improvements in the January 2006 issue of "Kidney & Blood Pressure." Launch of its online-first publication service; Emphasis of the issue on endocrine-derived high blood pressure and other secondary causes of hypertension; Effort of the editorial staff of the journal to provide researches concerning renal transplantation.

Discusses the contents of this issue, which includes the text of lectures presented at the 11th International ANCA and Vasculitis Workshop in Prague, Czech Republic in October, 2003. Lecture subjects, including the pathogenesis of vasculitis and important clinical aspects of vasculitis; Details of abstracts accepted for publication.

Introduction: Previous studies in Ren-2 transgenic hypertensive rats (TGR) after 5/6 renal ablation (5/6 NX) have shown that besides pharmacological blockade of the renin-angiotensin system (RAS) also increasing kidney tissue epoxyeicosatrienoic acids (EET) levels by blocking soluble epoxide hydrolase (sEH), an enzyme responsible for degradation of EETs, and endothelin type A (ETA) receptor blockade retards chronic kidney disease (CKD) progression. This prompted us to evaluate if this progression will be alleviated by the addition of sEH inhibitor and ETA receptor antagonist to the standard complex blockade of RAS (angiotensin-converting enzyme inhibitor plus angiotensin II type 1 receptor blocker) in rats with established CKD. Methods: The treatment regimens were initiated 6 weeks after 5/6 NX in TGR, and the follow-up period was 60 weeks. Results: The addition of sEH inhibition to RAS blockade improved survival rate, further reduced albuminuria and renal glomerular and kidney tubulointerstitial injury, and attenuated the decline in creatinine clearance – all this as compared with 5/6 NX TGR treated with RAS blockade alone. Addition of ETA receptor antagonist to the combined RAS and sEH blockade not only offered no additional renoprotection but, surprisingly, also abolished the beneficial effects of adding sEH inhibitor to the RAS blockade. Conclusion: These data indicate that pharmacological strategies that combine the blockade of RAS and sEH could be a novel tool to combat the progression of CKD. Any attempts to further extend this therapeutic regimen should be made with extreme caution.

Background: Pregnancy-associated plasma protein A (PAPP-A) is associated with adverse outcome of long-term hemodialysis patients (HD). The aim of the study was to test whether its homolog pregnancy-associated plasma protein A2 (PAPP-A2) can be detected in serum of HD patients and to define its significance. Methods: The studied group consisted of 102 long-term HD patients and 25 healthy controls. HD patients were prospectively followed up for five years (2009-2014). PAPP-A2 was measured by surface plasmon resonance biosensor, PAPP-A by time resolved amplified cryptate emission. Results: PAPP-A2, similarly as PAPP-A, was significantly increased in HD patients (median (interquartile range)) PAPP-A2: 6.2 (2.6-10.8) ng/mL, vs. 3.0 (0.7-5.9) ng/mL, p=0.006; PAPP-A: 18.9 (14.3-23.4) mIU/L, vs. 9.5 (8.4-10.5) mIU/L, p