Radial Artery Deviation and Reimplantation (RADAR) to Accelerate the Maturation of Radial-Cephalic Fistulas for Hemodialysis in Patients with End-Stage Renal Disease.

BACKGROUND: The most common form of vascular access for hemodialysis is a native arteriovenous fistula, which connects the site of the artery to the end of the vein. The maturation process of the fistula plays a crucial role in the establishment of a functional vascular access. Radial artery stenosis is among the potential causes of maturation failure. In these cases, improving the fistula's blood flow may be difficult, as traditional surgical reanastomosis and endovascular intervention frequently fail. Radial artery deviation and reimplantation (RADAR) is a novel and effective technique for creating primary fistulas with a high patency rate. The main disadvantage of this procedure is the ligation of the radial artery and the subsequent known consequences. METHODS: To accelerate maturation, we used RADAR as a secondary approach in three patients with radial artery stenosis and maturation failure. RESULTS: In all patients after surgery, we observed a significant increase in fistula blood flow. Two patients used fistulas for hemodialysis after surgery. We describe the image diagnosis, procedure, and benefits of this method. CONCLUSIONS: The RADAR technique may be successfully used as a secondary access in patients with maturation failure due to RA stenosis to accelerate fistula maturation.

Secondary IgA Nephropathy and IgA-Associated Nephropathy: A Systematic Review of Case Reports.

Primary (pIgAN), secondary IgA nephropathy (sIgAN), and IgA-associated nephropathy can be distinguished. While pIgAN has been thoroughly studied, information about the etiology of sIgAN remains scarce. As concerns sIgAN, several studies suggest that different etiologic factors play a role and ultimately lead to a pathophysiologic process similar to that of pIgAN. In this article, we review a vast number of cases in order to determine the novel putative underlying diseases of sIgAN. Moreover, updates on the common pathophysiology of primary disorders and sIgAN are presented. We identified liver, gastrointestinal, oncological, dermatological, autoimmune, and respiratory diseases, as well as infectious, iatrogenic, and environmental factors, as triggers of sIgAN. As novel biological therapies for listed underlying diseases emerge, we suggest implementing drug-induced sIgAN as a new significant category. Clinicians should acknowledge the possibility of sIgAN progression in patients treated with TNF-α inhibitors, IL-12/IL-23-inhibitors, immune checkpoint inhibitors, CTLA-4, oral anticoagulants, thioureylene derivatives, and anti-vascular endothelial growth factor drugs.

Baseline Proteinuria and Serum Creatinine Concentration as Clinical Predictors of Complete Renal Response in Patients with Lupus Nephritis: A Single-Center Experience.

The aim of the study was to identify robust predictors of complete renal response (CRR), within 36 months, in a single-center cohort of lupus nephritis (LN) patients. Patients with biopsy-confirmed LN who underwent kidney biopsy between 1 January 2010 and 31 December 2020 were included and followed up for at least 6 months. CRR was defined as a reduction of urinary protein-to-creatinine ratio (UPCR) below 0.50 g/g. We evaluated baseline demographic, laboratory, and biopsy characteristics as potential predictors of CRR, and selected the variables further evaluated with Kaplan−Meier curves and log-rank tests. The traits with a p-value < 0.1 were later tested with both uni- and multivariable Cox proportional hazard models. Our sample consisted of 57 patients (84% females, median age 32 years), out of which 63.2% reached CRR within 36 months. The initial UPCR and estimated glomerular filtration rate (eGFR) were the only variables in multivariable Cox regression model, which were selected through backward elimination, with a significance threshold <0.05 (HR = 0.77, p = 0.01 and HR = 1.02, p = 0.001). Our results confirmed the role of initial UPCR and serum creatinine concentration (sCr) as predictors of CRR in LN.

Artificial neural network - an effective tool for predicting the lupus nephritis outcome.

BACKGROUND: Lupus nephropathy (LN) occurs in approximately 50% of patients with systemic lupus erythematosus (SLE), and 20% of them will eventually progress into end-stage renal disease (ESRD). A clinical tool predicting remission of proteinuria might be of utmost importance. In our work, we focused on predicting the chance of complete remission achievement in LN patients, using artificial intelligence models, especially an artificial neural network, called the multi-layer perceptron. METHODS: It was a single centre retrospective study, including 58 individuals, with diagnosed systemic lupus erythematous and biopsy proven lupus nephritis. Patients were assigned into the study cohort, between 1st January 2010 and 31st December 2020, and eventually randomly allocated either to the training set (N = 46) or testing set (N = 12). The end point was remission achievement. We have selected an array of variables, subsequently reduced to the optimal minimum set, providing the best performance. RESULTS: We have obtained satisfactory results creating predictive models allowing to assess, with accuracy of 91.67%, a chance of achieving a complete remission, with a high discriminant ability (AUROC 0.9375). CONCLUSION: Our solution allows an accurate assessment of complete remission achievement and monitoring of patients from the group with a lower probability of complete remission. The obtained models are scalable and can be improved by introducing new patient records.

Prone Position Facilitates Creation of Ulnar-Basilic Arteriovenous Fistula.

BACKGROUND: The distal ulnar-basilic arteriovenous fistula (UBAVF) is a rarely used alternative type of vascular access for haemodialysis. The location of the vein on the back aspect of the forearm forces an extremely uncomfortable external rotation of the upper limb during surgery when the patient is in a supine position. METHODS: We present a new approach towards creating UBAVF, which involves placing the patient in the prone position, thus eliminating the aforementioned inconvenience. The procedure was performed and described in a 46-year-old patient with chronic kidney disease (CKD) due to diabetic nephropathy. In the period from September 2021 to December 2021, we created an additional three UBAVFs with such modifications. RESULTS: All fistulas were patent both immediately after the procedure and 2 weeks after surgery. CONCLUSIONS: The prone position may improve the comfort of both the operator and the patient during the procedure. On top of this, it may have a positive impact on the quality of the arteriovenous anastomosis.

Multisystem Amyloidosis in a Coal Miner with Silicosis: Is Exposure to Silica Dust a Cause of Amyloid Deposition?

The over-secretion of monoclonal immunoglobulin light chains by clonal B cells followed by the aggregation and extracellular deposition of fibrillar deposits are responsible forthe clinical course AL amyloidosis. It is well documented that silica significantly increases the number of immunoglobulin-secreting cells. In the present paper, we report on a coal miner with silicosis and fast progressing primary amyloidosis with predominantly heart, kidney, and lung manifestations. Severeheart failure due to myocardial hypertrophy resulted in the patient's death. We conclude that long-term environmental silica exposure and silica deposition may contribute to the development of monoclonal gammopathy and amyloidosis due to chronic stimulus and the dysregulation of the immune system.

Unintentional puncture of thyroid cyst during insertion of dialysis catheter.

Central venous catheter (CVC) for hemodialysis are frequently implanted to the internal jugular vein. Thyroid cysts are commonly shown in ultrasound examination and their recognition should not pose a problem. Herby we present an uncommon case of the thyroid cyst unintended puncture, during an attempt of CVC insertion. No further clinical consequences were observed. For all practitioners, involved in interventional nephrology, such complication may be of the utmost importance.

Peptide Charge Derivatization as a Tool for Early Detection of Preeclampsia by Mass Spectrometry-A Comparison with the ELISA Test.

Early detection of any preeclampsia biomarkers may lower the risk of mortality, both for a mother and a child. Our study focuses on techniques for preeclampsia biomarker identification by comparing the results of a method using liquid chromatography mass spectrometry in multiple reaction monitoring mode (LC-MS/MS) with those by the enzyme-linked immunosorbent assay (ELISA) test, as well as by comparing the obtained results with clinical data. In the proposed LC-MS/MS method a tryptic digest peptide charge derivatization strategy was used as a tool for sensitive detection of podocin, i.e., a previously discovered preeclampsia biomarker present in urine samples from pregnant women. Urine samples from pregnant women with diagnosed preeclampsia were collected at different stages of pregnancy and from healthy subjects, and then were analyzed by ELISA test and the proposed method with LC-MS/MS. Charge derivatization of the ε amino group of C-terminal lysine residues in tryptic digests by 2,4,6-triphenylpyrylium salt was performed to increase the ionization efficiency in the LC-MS/MS mode. Podocin was identified at the early stage of pregnancy, while its detection using an ELISA test was not possible. The protocol for urine sample preparation was optimized. Our results show that the proposed method by LC-MS/MS in combination with peptide charge derivatization, provides an ultrasensitive tool for diagnosis of preeclampsia, and provides earlier detection than a clinical diagnosis or ELISA test. The proposed solution may revolutionize medical diagnostics.

Clinical and Histopathological Factors Influencing IgA Nephropathy Outcome.

IgA nephropathy (IgAN) is the most frequent primary glomerulonephritis worldwide. Due to its heterogenicity, there is a need to establish robust biomarkers for IgAN, to support treatment decisions and evaluate the risk of progression to end-stage renal disease. Using both clinical and histopathological data, derived from renal biopsies, we aimed to find predictors of renal function deterioration and proteinuria reduction. Clinical and histopathological data of 80 patients with biopsy proven IgAN were analyzed. In a multivariate logarithmic regression model, the presence of endocapillary hypercellularity (E1) predicted a decline in estimated glomerular filtration rate (eGFR)of at least 50% with an odds ratio (OR) of 15.2, whereas serum albumin concentration had a negative influence on eGFR deterioration (OR 0.2). In the second multivariate model, the extent of interstitial fibrosis predicted the worsening of eGFR by 50% (OR 1.1) and serum albumin concentration had a protective impact (OR 0.1). In the univariate logarithmic regression, both the extent of interstitial fibrosis and the presence of endocapillary hypercellularity negatively correlated with the reduction in proteinuria below 1.0 g/24 h with an OR of 0.2 and 0.9, respectively. In our paper, we confirmed the utility of histopathological variables, especially endocapillary hypercellularity and interstitial fibrosis, and clinical parameters, particularly serum albumin concentration, in the prediction of both a decline in eGFR and a reduction in proteinuria in IgA nephropathy.

Selective ESI-MS detection of carbonyl containing compounds by aminooxyacetic acid immobilized on a resin.

There are numerous examples of bioactive compounds containing carbonyl groups including modified proteins with oxidation of side chain of amino acid residues to aldehyde/ketone groups which are frequently considered as markers of oxidative stress. The carbonyl unit can be also distinguished as a substructure in many illegal drugs including anabolic steroids as well as cations derivatives. Based on chemoselective formation of oximes by solid phase immobilized hydroxylamine derivatives we proposed the protocol for derivatization and selective detection of carbonylated compounds in human serum albumin hydrolysate as a complex peptide mixture and of testosterone in urine samples. This allowed for the removal of the matrix and the qualitative and quantitative analysis of the derivatized analyte by LC-MS/MS (or LC-MRM). Herein we report the preparation and chemical characterization of a novel, ChemMatrix - based resin functionalized with aminooxyacetic acid (AOA). The hydroxylamine moiety in this resin is combined with a peptide linker (GRG) containing an arginine residue to enhance the ionization efficiency. Application of an isotopically labeled carbonylated peptide ((H-Leu-Val-Thr(O)-Asp-Leu-Thr-Lys [13C6,15N2]-OH and testosterone-d3 allowed us to carry out quantitative analyses of detected compounds. Our method is general and may be applied for analysis of carbonylated compounds in biological samples. Our method based on application of functionalized resin allowed to quantify the level of free testosterone in small sample (0.5 mL) of urine, while the non-derivatized testosterone from urine sample was not detected during direct LC-MRM analysis.

Focal and segmental glomerulosclerosis in adults: early clinical course and prognostic factors for short-term outcome / Glomeruloesclerosis focal y segmentariaenadultos: evoluciónclínicatemprana y factorespronósticos de resultados a cortoplazo

ABSTRACT Background: Primary focal and segmental glomerulosclerosis progresses to end-stage renal disease in every other patient, and therefore determinants of its long-term outcome have been extensively studied. Immediate response to treatment has been regarded as a positive prognostic predictor and short-term manifestation of the disease could affect its determinants. Therefore, we have sought to assess the early clinical course of primary adult focal and segmental glomerulosclerosis and analyze its prognostic factors. Methods: We have retrospectively assessed clinical course of primary focal and segmental glomerulosclerosis ("not otherwise specified" histological variant) in 84 adults. Renal function was expressed as serum creatinine concentration and equilibrated glomerular filtration rate (MDRD equation). Proteinuria was expressed as protein to urinary creatinine ratio, assessed in the morning voiding sample. The evaluation of these parameters was performed every 3 months after diagnosis. Statistical analysis was achieved using package Statistica. Results: As result of treatment, complete remission of proteinuria, was attained in 30 subjects (35.7%), partial remission in 37 persons (44%), whereas in 17 patients protein excretion rate remained unchanged (20.2%). The severity of glomerular injury, at initial presentation of the disease, correlated with its early (12 months) outcome: patients attaining early complete remission have had the lowest initial proteinuria, higher serum albumin and total protein concentrations than those who have failed to achieve remission. Pharmacotherapy with prednisone, but not with calcineurin inhibitors or mycophenolate mofetil was demonstrated to significantly affect achievement of remission. Conclusions: Early remission of proteinuria in response to treatment is feasible in 44% of patients with primary focal and segmental glomerulosclerosis, it is best achieved in subjects presenting with mild glomerular injury, and in patients treated with prednisone. Higher serum albumin and total protein concentrations predict better response to induction of remission.

RESUMEN Antecedentes: La glomeruloesclerosis focal y segmentaria se convierteennefropatía terminal enuno de cada dos pacientes, por lo que losfactoresdeterminantes de susdesenlaces a largo plazohansidoobjeto de muchosestudios. La respuestainmediata al tratamiento se considera un factor pronóstico favorable, y las manifestaciones a cortoplazo de la enfermedadpuedenafectarlosfactoresdeterminantes. Portodoello, hemosbuscadoevaluar la evoluciónclínicatemprana de la glomeruloesclerosis focal y segmentariaprimaria, y analizarsusfactorespronósticos. Material y métodos: Hemosrealizado un estudioretrospectivo para evaluar la evoluciónclínica de la glomeruloesclerosis focal y segmentariaprimaria (variantehistológica "sin otraespecificación") en 84 pacientesadultos. Se evaluó la función renal a través de la creatininasérica y filtrado glomerular equilibradocalculadomediante la ecuación MDRD. La proteinuria se expresócomorelaciónproteína/creatininaurinaria, evaluadaen la muestramiccionalmatutina. La evaluación de estosparámetros se realizócada 3 mesesdespués del diagnóstico. El análisisestadístico se logróutilizando el paqueteStatistica. Resultados: Como resultado del tratamiento, se obtuvounaremisióncompleta de la proteinuria en 30 sujetos (35,7%), unaremisiónparcialen 37 personas (44%), mientras que, en 17 pacientes, la tasa de excreción de proteínas se mantuvo sin cambios (20,2%). En la presentacióninicial de la enfermedad, la gravedad de la lesión glomerular se correlacionó con suresultadotemprano (12 meses): lospacientes que lograronunaremisióncompletatempranamostraronlosnivelesmásbajos de proteinuria inicial, y concentracionesmásaltas de albúminasérica y proteínastotales que aquellos que no alcanzaron la remisión. Se demostró que la farmacoterapia con prednisona -pero no con inhibidores de calcineurina o micofenolato de mofetilo- condiciona de forma significativa el logro de la remisión. Conclusiones: La remisióntemprana de la proteinuria enrespuesta al tratamientoesfactibleen el 44% de lospacientes con glomeruloesclerosis focal y segmentariaprimaria; se obtienenmejoresresultadosensujetos que presentanunalesión glomerular leve y enpacientestratados con prednisona. Las concentracionesmásaltas de albúminasérica y proteínastotalespredicenunamejorrespuesta para inducir la remisión.

Exhausted Capacity of Bicarbonate Buffer in Renal Failure Diagnosed Using Point of Care Analyzer.

BACKGROUND: Metabolic acidosis in patients with chronic kidney disease (CKD) is a common complication. A bicarbonate concentration in venous blood (V-HCO3-) is a key index for diagnosis and treatment initiation. The aim of our study is to evaluate usability of acid-base balance parameters of in blood taken simultaneously from peripheral artery and the vein. METHODS: A total of 49 patients (median age 66 years [interquartile range IQR 45-75]), with CKD stage G4 or G5 were enrolled in this cross-sectional study. All patients were qualified for arteriovenous fistula creation in pre-dialysis period. The samples were taken during surgery, directly after dissection, and evaluated in a point of care testing analyzer. The arteriovenous difference in bicarbonate levels (Δ-HCO3-) was calculated. According to glomerular filtration rate (eGFR) the group was divided into Group A eGFR ≥ 10 mL/min/1.73 m2) and Group B eGFR < 10 mL/min/1.73 m2). RESULTS: In Group A Δ-HCO3- was significantly higher compared to Group B. No such differences were observed in the case of V-HCO3-. Δ-HCO3- positively correlated with eGFR. The discriminative power of Δ-HCO3- for predicting eGFR < 10 mL/min/1.73 m2 was 0.72 (95% confidence interval [CI] = 0.551-0.88; p = 0.01) which provided 67% sensitivity and 75% specificity. The best cut-off was 0.5 mmol/L. CONCLUSIONS: The Δ-HCO3- lower than 0.5 mmol/L may be used as predictor of exhaust buffer capacity. The value of this tool should be tested in larger population.

Enrichment of Cysteine-Containing Peptide by On-Resin Capturing and Fixed Charge Tag Derivatization for Sensitive ESI-MS Detection.

High complexity of cell and tissue proteomes limits the investigation of proteomic biomarkers. Therefore, the methods of enrichment of some chemical groups of peptides including thiopeptides are important tools that may facilitate the proteomic analysis by reducing sample complexity and increasing proteome coverage. Here, we present a new method of cysteine-containing tryptic peptide enrichment using commercially available TentaGel R RAM resin modified by the linker containing the maleimide group, allowing thiol conjugation. The captured tryptic peptides containing lysine residue were then tagged by 2,4,6-triphenylpyrylium salt to form 2,4,6-triphenylpyridinium derivatives, which increases the ionization efficiency during mass spectrometry analysis. This makes it possible to conduct an ultrasensitive analysis of the trace amount of compounds. The proposed strategy was successfully applied in the enrichment of model tryptic podocin peptide and podocin tryptic digest.

Evaluation of Tryptic Podocin Peptide in Urine Sediment Using LC-MS-MRM Method as a Potential Biomarker of Glomerular Injury in Dogs with Clinical Signs of Renal and Cardiac Disorders.

The early asymptomatic stage of glomerular injury is a diagnostic challenge in the course of renal and extra-renal disease, e.g., heart insufficiency. It was found that podocin, a podocyte-specific protein present in the urine, may serve as a biomarker in the diagnosis of glomerular disease in humans and animals including glomerulonephritis, glomerulosclerosis, amyloidosis, or nephropathy. Therefore, there is a need of development of the sensitive and straightforward method of urinary podocin identification. In this work, we report our extended research under the glomerular injury investigation in dogs by application of clinical examination and LC-MS-MRM method in the identification of canine podocin in urine samples. The LC-MS-MRM method is based on the identification of podocin tryptic peptide with the 218H-AAEILAATPAAVQLR-OH232 sequence. The model peptide was characterized by the highest ionization efficiency of all the proposed model podocin tryptic peptides in a canine urine sediment according to the LC-MS/MS analysis. The obtained results revealed the presence of the model peptide in 40.9% of dogs with MMVD (active glomerular injury secondary to heart disease = cardiorenal syndrome-CRS) and 33.3% dogs with chronic kidney disease. The potential applicability of the developed methodology in the analysis of podocin in canine urine sediments was confirmed.

Safety Studies of Pneumococcal Endolysins Cpl-1 and Pal.

Bacteriophage-derived endolysins have gained increasing attention as potent antimicrobial agents and numerous publications document the in vivo efficacy of these enzymes in various rodent models. However, little has been documented about their safety and toxicity profiles. Here, we present preclinical safety and toxicity data for two pneumococcal endolysins, Pal and Cpl-1. Microarray, and gene profiling was performed on human macrophages and pharyngeal cells exposed to 0.5 µM of each endolysin for six hours and no change in gene expression was noted. Likewise, in mice injected with 15 mg/kg of each endolysin, no physical or behavioral changes were noted, pro-inflammatory cytokine levels remained constant, and there were no significant changes in the fecal microbiome. Neither endolysin caused complement activation via the classic pathway, the alternative pathway, or the mannose-binding lectin pathway. In cellular response assays, IgG levels in mice exposed to Pal or Cpl-1 gradually increased for the first 30 days post exposure, but IgE levels never rose above baseline, suggesting that hypersensitivity or allergic reaction is unlikely. Collectively, the safety and toxicity profiles of Pal and Cpl-1 support further preclinical studies.

Breast Involvement in Anti-Neutrophil Cytoplasmic Antibodies Positive Granulomatosis With Polyangiitis in a 64-Year-Old Female Patient.

In this article, we present a case of a female patient suffering from granulomatosis and polyangiitis with active glomerular disease, who developed exacerbation of pulmonary vasculitis and palpable tumors of right breast. A possibility of neoplastic disease was excluded by histopathological examination of percutaneous biopsy specimen, revealing granulomatous inflammatory infiltrate, without any features of neoplasia. Moreover, both pulmonary and breast lesions subsided following intensification of immunosuppressive/antiinflammatory treatment.

[Long term course of chronic thromboembolic pulmonary hypertension, not preceded by acute, treated pulmonary embolic event]. / Dlugotrwala obserwacja przebiegu przewleklego zakrzepowo zatorowego nadcisnienia plucnego nie poprzedzonego ostrym, leczonym plucnym incydentem zatorowym.

Chronic thromboembolic pulmonary hypertension (CTEPH) may develop as a consequence of silent or symptomatic but unrecognized and not treated thromboembolic events, however, its course is little known. A prospective study with once a year evaluation of survival, Doppler-derived systolic pulmonary artery pressure (PASP), functional NYHA class, and exercise tolerance in a group of 26 newly diagnosed CTEPH patients aging 37 to 82 years with mean pulmonary artery pressure (MPAP) ranging from 21 to 86 mmHg was undertaken. None of patients underwent pulmonary endarterectomy (10 patients had distal embolism, 4 patients had proximal embolism and MPAP < 30 mmHg, 12 patients with proximal embolism and MPAP>30mmHg did not accept risk of surgery). After starting anticoagulation, the 3-year survival in 13 patients with baseline MPAP < 33mmHg was 100%. In these patients PASP decreased < 40 mmHg after 1,2 and 3 year in seven, nine and in all but one patient, respectively. NYHA class improved in 12 patients and trend to increase number of METS during exercise test (p = 0.09) was found. The survival rate for 13 patients with MPAP > 33 mmHg was respectively 77%, 62% and 46%. 3 patients with MPAP > 69 mmHg died before 1 year of follow-up. In summary, patients with newly diagnosed CTEPH preceded by silent or unrecognized thromboembolic events, with MPAP > 33mmHg should be promptly operated whereas patients with MPAP < 33 mmHg, can be initially treated by anticoagulation alone and should be followed regularly with echocardiography, assessment of NYHA class and exercise tolerance.

The clinicopathological determinants of native arteriovenous fistula failure in patients on maintenance hemodialysis.

BACKGROUND: Progressive narrowing of the venous part of dialysis fistulae is caused by hemodynamic and inflammatory factors. OBJECTIVES: The pathogenic and clinical determinants of deterioration of the functioning of arteriovenous fistulae in chronically hemodialyzed patients were evaluated. MATERIAL AND METHODS: The hemodynamic parameters and the activity of inflammatory growth factors in the vessel wall of newly implanted fistulae were assessed and correlated with the clinical course of 34 hemodialyzed patients. Measurements taken at the time of implanting the fistulae included blood flow in the venous part of the anastomosis and its widest diameter by ultrasound Power Doppler, a histopathologic examination of fistula wall samples and measurements of mRNA expression for growth factors PDGFß1 and TGFß in the fistula wall. The results were correlated with clinical data from 36 months' observation: duration of fistula maturation, adequacy of dialysis treatment (eKt/V), the patient's survival, morbidity linked with vascular access problems and general cardiovascular morbidity. RESULTS: The mean duration of fistula maturation was 44.9 days (N = 43, SD = 38.6), whereas the average duration of fistula usage as dialysis access was 795.9 ± 480.6 days. Fistula blood flow at the time of implantation, averaged 1782.2 ± 1735.3 ml/min. The mean number of hospitalization days due to vascular access morbidity was 9.9 ± 15.6 days and it correlated positively with the fistula blood flow (R = 0.596, P = 0.004). There was a negative correlation between the expression of PDGFß1 mRNA and fistula blood flow (R = -0.673, P = 0.011), as well as between TGFß expression and patient survival (R = -0.722, P = 0.002). CONCLUSIONS: Inflammatory activity of the vessel wall growth factors PDGFß1 and TGFß implies impairment of fistula function and the patient's cardiovascular morbidity.

Late angiotensin II receptor blockade in progressive rat mesangioproliferative glomerulonephritis: new insights into mechanisms.

Mesangioproliferative glomerulonephritis is the most common nephritis worldwide. We examined the effects of low- and high-dose telmisartan, an angiotensin II receptor blocker, in rats with progressive anti-Thy1.1 mesangioproliferative glomerulonephritis in a clinically relevant situation of established renal damage. Uninephrectomized nephritic rats were randomized on day 28 to remain untreated (control treatment; CT), or to receive low- (0.1 mg/kg/day, LT) or high-dose telmisartan (10 mg/kg/day, HT), hydrochlorothiazide + hydralazine (8 + 32 mg/kg/day, HCT + H), or atenolol (100 mg/kg/day, AT). CT and LT rats were hypertensive, whereas HT, HCT + H and AT treatment normalized blood pressures. On day 131, despite similar blood lowering effects, only HT, but not AT or HCT + H, prevented loss of renal function and reduced proteinuria compared to CT. Only HT potently ameliorated glomerulosclerosis, tubulointerstitial damage, cortical matrix deposition, podocyte damage and macrophage infiltration. HT reduced cortical expression of platelet derived growth factor receptor-α and -ß as well as transforming growth factor-ß1. LT exhibited minor but significant efficacy even in the absence of antihypertensive effects. Transcript array analyses revealed a four-fold down-regulation of renal cortical chemokine (C-C motif) receptor 6 (CCR6) mRNA by HT, which was confirmed at the protein level. Silencing of CCR6 did not alter podocyte function in vitro, thus indicating a predominant role in the tubulo-interstitium. In human kidney biopsies, CCR6 mRNA and mRNA of its ligand chemokine (C-C motif) ligand 20 was up-regulated in patients with progressive IgA nephropathy compared to stable disease. Thus, delayed treatment with high-dose telmisartan exerted a pronounced benefit in progressive mesangioproliferative glomerulonephritis, which extended beyond that of equivalent blood pressure lowering. We identified down-regulation of platelet-derived growth factor receptors and CCR6 as potential mediators of telmisartan-related renoprotection. CCR6 may also regulate the renal outcome in human mesangioprolfierative glomerulonephritis.