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Tang C, Chen P, Si FL, Lv JC, Shi SF, Zhou XJ, Liu LJ, Zhang H. Time-Varying Proteinuria and Progression of IgA Nephropathy: A Cohort Study. Am J Kidney Dis 2024; 84:170-178.e1. [PMID: 38364955 DOI: 10.1053/j.ajkd.2023.12.016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2023] [Revised: 11/20/2023] [Accepted: 12/08/2023] [Indexed: 02/18/2024]
Abstract
RATIONALE & OBJECTIVE Proteinuria is a surrogate end point for predicting long-term kidney outcomes in IgA nephropathy (IgAN) with levels<1g/day identified as a therapeutic target. However, this threshold has not been sufficiently studied. We quantified the associations of progression of IgAN with various levels of proteinuria. STUDY DESIGN Observational cohort study. SETTING & PARTICIPANTS 1,530 patients with IgAN and at least 12 months of follow-up at Peking University First Hospital. EXPOSURE Proteinuria levels updated over time (time-varying proteinuria, TVP). OUTCOME A composite kidney outcome of a 50% reduction in the estimated glomerular filtration rate or end-stage kidney disease. ANALYTICAL APPROACH Marginal structural models. RESULTS After a median follow-up period of 43.5 (IQR, 27.2-72.8) months, 254 patients (16.6%) developed the composite kidney outcome. A graded association was observed between TVP and composite kidney outcomes with higher risk among those with proteinuria of≥0.5g/day. Compared with TVP<0.3g/day, the HRs for proteinuria levels of 0.3 to<0.5g/day, 0.5 to<1.0g/day, 1.0 to<2.0g/day, and≥2.0g/day were 2.22 (95% CI, 0.88-5.58), 4.04 (95% CI, 1.93-8.46), 8.46 (95% CI, 3.80-18.83), and 38.00 (95% CI, 17.62-81.95), respectively. The trend was more pronounced in patients with baseline proteinuria of≥1.0g/day, among whom a higher risk was observed with TVP of 0.3 to<0.5g/day compared with TVP<0.3g/day (HR, 3.26 [95% CI, 1.07-9.92], P=0.04). However, in patients with baseline proteinuria levels of<1g/day, the risk of composite kidney outcome only began to increase when TVP was≥1.0g/day (HR, 3.25 [95% CI, 1.06-9.90]). LIMITATIONS Single-center observational study, selection bias, and unmeasured confounders. CONCLUSIONS This study showed that patients with IgAN and proteinuria levels of>0.5g/day, have an elevated risk of kidney failure especially among patients with proteinuria levels≥1.0g/day before initiating treatment. These data may serve to inform the selection of proteinuria targets in the treatment of IgAN. PLAIN-LANGUAGE SUMMARY The presence of proteinuria has often been considered a surrogate end point and a possible therapeutic target in clinical trials in IgA nephropathy (IgAN). Some guidelines recommend a reduction in proteinuria to<1g/day as a treatment goal based on the results of previous longitudinal studies. However, these findings may have been biased because they did not properly adjust for time-dependent confounders. Using marginal structural models to appropriately account for these confounding influences, we observed that patients with IgAN and proteinuria levels≥0.5g/day have an elevated risk of kidney failure, especially among patients who had proteinuria levels of≥1.0g/day before initiating treatment. These data may serve to inform the selection of proteinuria targets in the treatment of IgAN.
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Affiliation(s)
- Chen Tang
- Renal Division, Peking University First Hospital, Peking University Institute of Nephrology, Key Laboratory of Renal Disease, Ministry of Health of China, Key Laboratory of Chronic Kidney Disease Prevention and Treatment (Peking University), Ministry of Education, and Research Units of Diagnosis and Treatment of Immune-Mediated Kidney Diseases, Chinese Academy of Medical Sciences, Beijing, People's Republic of China
| | - Pei Chen
- Renal Division, Peking University First Hospital, Peking University Institute of Nephrology, Key Laboratory of Renal Disease, Ministry of Health of China, Key Laboratory of Chronic Kidney Disease Prevention and Treatment (Peking University), Ministry of Education, and Research Units of Diagnosis and Treatment of Immune-Mediated Kidney Diseases, Chinese Academy of Medical Sciences, Beijing, People's Republic of China
| | - Feng-Lei Si
- Renal Division, Peking University First Hospital, Peking University Institute of Nephrology, Key Laboratory of Renal Disease, Ministry of Health of China, Key Laboratory of Chronic Kidney Disease Prevention and Treatment (Peking University), Ministry of Education, and Research Units of Diagnosis and Treatment of Immune-Mediated Kidney Diseases, Chinese Academy of Medical Sciences, Beijing, People's Republic of China
| | - Ji-Cheng Lv
- Renal Division, Peking University First Hospital, Peking University Institute of Nephrology, Key Laboratory of Renal Disease, Ministry of Health of China, Key Laboratory of Chronic Kidney Disease Prevention and Treatment (Peking University), Ministry of Education, and Research Units of Diagnosis and Treatment of Immune-Mediated Kidney Diseases, Chinese Academy of Medical Sciences, Beijing, People's Republic of China
| | - Su-Fang Shi
- Renal Division, Peking University First Hospital, Peking University Institute of Nephrology, Key Laboratory of Renal Disease, Ministry of Health of China, Key Laboratory of Chronic Kidney Disease Prevention and Treatment (Peking University), Ministry of Education, and Research Units of Diagnosis and Treatment of Immune-Mediated Kidney Diseases, Chinese Academy of Medical Sciences, Beijing, People's Republic of China
| | - Xu-Jie Zhou
- Renal Division, Peking University First Hospital, Peking University Institute of Nephrology, Key Laboratory of Renal Disease, Ministry of Health of China, Key Laboratory of Chronic Kidney Disease Prevention and Treatment (Peking University), Ministry of Education, and Research Units of Diagnosis and Treatment of Immune-Mediated Kidney Diseases, Chinese Academy of Medical Sciences, Beijing, People's Republic of China
| | - Li-Jun Liu
- Renal Division, Peking University First Hospital, Peking University Institute of Nephrology, Key Laboratory of Renal Disease, Ministry of Health of China, Key Laboratory of Chronic Kidney Disease Prevention and Treatment (Peking University), Ministry of Education, and Research Units of Diagnosis and Treatment of Immune-Mediated Kidney Diseases, Chinese Academy of Medical Sciences, Beijing, People's Republic of China.
| | - Hong Zhang
- Renal Division, Peking University First Hospital, Peking University Institute of Nephrology, Key Laboratory of Renal Disease, Ministry of Health of China, Key Laboratory of Chronic Kidney Disease Prevention and Treatment (Peking University), Ministry of Education, and Research Units of Diagnosis and Treatment of Immune-Mediated Kidney Diseases, Chinese Academy of Medical Sciences, Beijing, People's Republic of China
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Park SK, Jung JY, Kim MH, Oh CM, Shin S, Ha E, Lee S, Jung MH, Ryoo JH. Changes in urine dipstick proteinuria and its relation to the risk of diabetic retinopathy and neuropathy. Endocrine 2024:10.1007/s12020-024-03928-8. [PMID: 38907116 DOI: 10.1007/s12020-024-03928-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/31/2024] [Accepted: 06/10/2024] [Indexed: 06/23/2024]
Abstract
BACKGROUND Proteinuria is considered as a predictor for cardiovascular complications in diabetes mellitus (DM). However, no study has examined the association between changes in proteinuria and the risk of diabetic microvascular complications. METHODS Study participants were 71,825 DM patients who received urine dipstick test for proteinuria both in 2003-2004 and 2006-2007. They were categorized into four groups according to changes in proteinuria over 3 years (negative: negative → negative, resolved: proteinuria ≥ 1+ → negative, incident: negative → proteinuria ≥ 1+, persistent: proteinuria ≥ 1+ → proteinuria ≥ 1+). Cox-proportional hazard model was used in assessing the adjusted hazard ratios (HR) and 95% confidence interval (CI) for incidence of retinopathy, and neuropathy (adjusted HR [95% CI]). RESULT In all of DM patients, risk for comprehensive incidence of retinopathy and neuropathy increased in all types of proteinuria changes. In type 1 DM, HR for retinopathy and neuropathy generally increased in order of negative (reference), resolved (2.175 [1.150-4.114] and 1.335 [0.909-1.961]), incident (2.088 [1.185-3.680] and 1.753 [1.275-2.409]), and persistent proteinuria (1.314 [0.418-4.134] and 2.098 [1.274-3.455]). This pattern of relationship was similarly observed in type 2 DM for retinopathy and neuropathy: negative (reference), resolved (1.490 [1.082-2.051] and 1.164 [0.988-1.371]), incident (1.570 [1.161-2.123] and 1.291 [1.112-1.500]), and persistent proteinuria (2.309 [1.407-3.788] and 1.272 [0.945-1.712]). CONCLUSION Risk for diabetic retinopathy and neuropathy generally increased in order of negative, resolved, incident, and persistent proteinuria. Once manifested proteinuria was associated with the increased risk of diabetic retinopathy and neuropathy even after remission of proteinuria.
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Affiliation(s)
- Sung Keun Park
- Total Healthcare Center, Kangbuk Samsung Hospital, Sungkyunkwan University, School of Medicine, Seoul, Korea
| | - Ju Young Jung
- Total Healthcare Center, Kangbuk Samsung Hospital, Sungkyunkwan University, School of Medicine, Seoul, Korea
| | - Min-Ho Kim
- Ewha Medical Data Organization, Ewha Womans University Seoul Hospital, Seoul, Korea
| | - Chang-Mo Oh
- Departments of Preventive Medicine, School of Medicine, Kyung Hee University, Seoul, Korea
| | - Soonsu Shin
- Department of Occupational and Environment Medicine, Kyung Hee University Hospital, Seoul, Korea
| | - Eunhee Ha
- Department of Occupational and Environment Medicine, College of Medicine, Ewha Womans University, Seoul, Korea
| | - Sangho Lee
- Department of Anesthesiology and Pain Medicine, Kyung Hee University College of Medicine, Kyung Hee University Hospital, Seoul, Korea
| | - Min Hyung Jung
- Department of Obstetrics and Gynecology, School of Medicine, Kyung Hee University, Seoul, Korea
| | - Jae-Hong Ryoo
- Departments of Occupational and Environmental Medicine, School of Medicine, Kyung Hee University, Seoul, Korea.
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Wu Y, Benson MA, Sun SX. Cell-Driven Fluid Dynamics: A Physical Model of Active Systemic Circulation. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.05.19.594862. [PMID: 38826192 PMCID: PMC11142051 DOI: 10.1101/2024.05.19.594862] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2024]
Abstract
Active fluid circulation and transport are key functions of living organisms, which drive efficient delivery of oxygen and nutrients to various physiological compartments. Because fluid circulation occurs in a network, the systemic flux and pressure are not simple outcomes of any given component. Rather, they are emergent properties of network elements and network topology. Moreover, consistent pressure and osmolarity gradients across compartments such as the kidney, interstitium, and vessels are known. How these gradients and network properties are established and maintained is an unanswered question in systems physiology. Previous studies have shown that epithelial cells are fluid pumps that actively generate pressure and osmolarity gradients. Polarization and activity of ion exchangers that drive fluid flux in epithelial cells are affected by pressure and osmolarity gradients. Therefore, there is an unexplored coupling between the pressure and osmolarity in the circulating network. Here we develop a mathematical theory that integrates the influence of pressure and osmolarity on solute transport and explores both cell fluid transport and systemic circulation. This model naturally generates pressure and osmolarity gradients across physiological compartments, and demonstrates how systemic transport properties can depend on cell properties, and how the cell state can depend on systemic properties. When epithelial and endothelial pumps are considered together, we predict how pressures at various points in the network depend on the overall osmolarity of the system. The model can be improved by including physiological geometries and expanding solute species, and highlights the interplay of fluid properties with cell function in living organisms.
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Affiliation(s)
- Yufei Wu
- Department of Mechanical Engineering, Johns Hopkins University, Baltimore, Maryland, USA
- Institute for NanoBioTechnology, Johns Hopkins University, Baltimore, Maryland, USA
| | - Morgan A. Benson
- Department of Mechanical Engineering, Johns Hopkins University, Baltimore, Maryland, USA
- Institute for NanoBioTechnology, Johns Hopkins University, Baltimore, Maryland, USA
| | - Sean X. Sun
- Department of Mechanical Engineering, Johns Hopkins University, Baltimore, Maryland, USA
- Institute for NanoBioTechnology, Johns Hopkins University, Baltimore, Maryland, USA
- Center for Cell Dynamics, Johns Hopkins School of Medicine, Baltimore, Maryland, USA
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4
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Kato T, Mizuno R, Miyake H. Prevalence and management of proteinuria associated with vascular endothelial growth factor receptor-targeted tyrosine kinase inhibitor treatment in advanced renal cell carcinoma, hepatocellular carcinoma, and thyroid cancer. Int J Urol 2024; 31:465-474. [PMID: 38318663 DOI: 10.1111/iju.15409] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2023] [Accepted: 01/17/2024] [Indexed: 02/07/2024]
Abstract
Vascular endothelial growth factor receptor-targeted tyrosine kinase inhibitors (VEGFR-TKIs) are often used for treatment of several types of cancer; however, they are associated with an increased risk of proteinuria, sometimes leading to treatment discontinuation. We searched PubMed and Scopus to identify clinical studies examining the incidence and risk factors for proteinuria caused by VEGFR-TKIs in patients with renal cell carcinoma, thyroid cancer, and hepatocellular carcinoma. The global incidence of proteinuria ranged from 6% to 34% for all grades of proteinuria, and from 1% to 10% for grade ≥3 proteinuria. The incidence of proteinuria did not differ significantly by cancer type, but in all three cancer types, there was a trend toward a higher incidence of proteinuria with lenvatinib than with other VEGFR-TKIs. In terms of risk factors, the incidence of proteinuria was significantly higher among Asians (including Japanese) compared with non-Asian populations. Other risk factors included diabetes mellitus, hypertension, and previous nephrectomy. When grade 3/4 proteinuria occurs, patients should be treated according to the criteria for dose reduction or withdrawal specified for each drug. For grade 2 proteinuria, treatment should be continued when the benefits outweigh the risks. Referral to a nephrologist should be considered for symptoms related to decreased renal function or when proteinuria has not improved after medication withdrawal. These management practices should be implemented universally, regardless of the cancer type.
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Affiliation(s)
- Taigo Kato
- Department of Urology, Osaka University Graduate School of Medicine, Osaka, Japan
| | - Ryuichi Mizuno
- Department of Urology, Keio University School of Medicine, Tokyo, Japan
| | - Hideaki Miyake
- Division of Urology, Kobe University Graduate School of Medicine, Hyogo, Japan
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Pollmann NS, Vogel T, Pongs C, Katou S, Morgül H, Houben P, Görlich D, Kneifel F, Reuter S, Pollmann L, Pascher A, Becker F. Donor Proteinuria and Allograft Function in Kidney Transplantation: Short- and Long-Term Results From a Retrospective Cohort Study. Transpl Int 2023; 36:11953. [PMID: 38156296 PMCID: PMC10754218 DOI: 10.3389/ti.2023.11953] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2023] [Accepted: 11/13/2023] [Indexed: 12/30/2023]
Abstract
Donor proteinuria (DP) is a common but rarely evaluated aspect of today's kidney transplant allocation process. While proteinuria after kidney transplantation is a risk factor for impaired graft function and survival, the long-term effects of DP in kidney transplantation have not yet been evaluated. Therefore, this study aims to investigate the impact of DP on the long-term outcome after kidney transplantation. A total of 587 patients were found to be eligible and were stratified into two groups: (1) those receiving a graft from a donor without proteinuria (DP-) and (2) those receiving a graft from a donor with proteinuria (DP+). At 36 months, there was no difference in the primary composite endpoint including graft loss and patient survival (log-rank test, p = 0.377). However, the analysis of DP+ subgroups showed a significant decrease in overall patient survival in the group with high DP (p = 0.017). DP did not adversely affect patient or graft survival over 36 months. Nevertheless, this work revealed a trend towards decreased overall survival of patients with severe proteinuria in the subgroup analysis. Therefore, the underlying results suggest caution in allocating kidneys from donors with high levels of proteinuria.
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Affiliation(s)
- Nicola Sariye Pollmann
- Department of General, Visceral and Transplant Surgery, University Hospital Muenster, Muenster, Germany
| | - Thomas Vogel
- Department of General, Visceral and Transplant Surgery, University Hospital Muenster, Muenster, Germany
| | - Caroline Pongs
- Department of General, Visceral and Transplant Surgery, University Hospital Muenster, Muenster, Germany
| | - Shadi Katou
- Department of General, Visceral and Transplant Surgery, University Hospital Muenster, Muenster, Germany
| | - Haluk Morgül
- Department of General, Visceral and Transplant Surgery, University Hospital Muenster, Muenster, Germany
| | - Philipp Houben
- Department of General, Visceral and Transplant Surgery, University Hospital Muenster, Muenster, Germany
| | - Dennis Görlich
- Institute of Biostatistics and Clinical Research, University Hospital Muenster, Muenster, Germany
| | - Felicia Kneifel
- Department of General, Visceral and Transplant Surgery, University Hospital Muenster, Muenster, Germany
| | - Stefan Reuter
- Department of Medicine D, Division of General Internal Medicine, Nephrology and Rheumatology, University Hospital Muenster, Muenster, Germany
| | - Lukas Pollmann
- Department of General, Visceral and Transplant Surgery, University Hospital Muenster, Muenster, Germany
| | - Andreas Pascher
- Department of General, Visceral and Transplant Surgery, University Hospital Muenster, Muenster, Germany
| | - Felix Becker
- Department of General, Visceral and Transplant Surgery, University Hospital Muenster, Muenster, Germany
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Pokidysheva EN, Redhair N, Ailsworth O, Page-McCaw P, Rollins-Smith L, Jamwal VS, Ohta Y, Bächinger HP, Murawala P, Flajnik M, Fogo AB, Abrahamson D, Hudson JK, Boudko SP, Hudson BG. Collagen IV of basement membranes: II. Emergence of collagen IV α345 enabled the assembly of a compact GBM as an ultrafilter in mammalian kidneys. J Biol Chem 2023; 299:105459. [PMID: 37977222 PMCID: PMC10746531 DOI: 10.1016/j.jbc.2023.105459] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2023] [Revised: 10/28/2023] [Accepted: 10/31/2023] [Indexed: 11/19/2023] Open
Abstract
The collagen IVα345 (Col-IVα345) scaffold, the major constituent of the glomerular basement membrane (GBM), is a critical component of the kidney glomerular filtration barrier. In Alport syndrome, affecting millions of people worldwide, over two thousand genetic variants occur in the COL4A3, COL4A4, and COL4A5 genes that encode the Col-IVα345 scaffold. Variants cause loss of scaffold, a suprastructure that tethers macromolecules, from the GBM or assembly of a defective scaffold, causing hematuria in nearly all cases, proteinuria, and often progressive kidney failure. How these variants cause proteinuria remains an enigma. In a companion paper, we found that the evolutionary emergence of the COL4A3, COL4A4, COL4A5, and COL4A6 genes coincided with kidney emergence in hagfish and shark and that the COL4A3 and COL4A4 were lost in amphibians. These findings opened an experimental window to gain insights into functionality of the Col-IVα345 scaffold. Here, using tissue staining, biochemical analysis and TEM, we characterized the scaffold chain arrangements and the morphology of the GBM of hagfish, shark, frog, and salamander. We found that α4 and α5 chains in shark GBM and α1 and α5 chains in amphibian GBM are spatially separated. Scaffolds are distinct from one another and from the mammalian Col-IVα345 scaffold, and the GBM morphologies are distinct. Our findings revealed that the evolutionary emergence of the Col-IVα345 scaffold enabled the genesis of a compact GBM that functions as an ultrafilter. Findings shed light on the conundrum, defined decades ago, whether the GBM or slit diaphragm is the primary filter.
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Affiliation(s)
- Elena N Pokidysheva
- Division of Nephrology and Hypertension, Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee, USA; Aspirnaut, Vanderbilt University Medical Center, Nashville, Tennessee, USA; Center for Matrix Biology, Vanderbilt University Medical Center, Nashville, Tennessee, USA.
| | - Neve Redhair
- Aspirnaut, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - Octavia Ailsworth
- Aspirnaut, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - Patrick Page-McCaw
- Division of Nephrology and Hypertension, Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee, USA; Center for Matrix Biology, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - Louise Rollins-Smith
- Department of Pathology Microbiology and Immunology, Vanderbilt University School of Medicine, Nashville, Tennessee, USA
| | | | - Yuko Ohta
- Department of Microbiology and Immunology, School of Medicine, University of Maryland, Baltimore, Maryland, USA
| | | | - Prayag Murawala
- Mount Desert Island Biological Laboratory, Bar Harbor, Maine, USA; Clinic for Kidney and Hypertension Diseases, Hannover Medical School, Hannover, Germany
| | - Martin Flajnik
- Department of Microbiology and Immunology, School of Medicine, University of Maryland, Baltimore, Maryland, USA
| | - Agnes B Fogo
- Division of Nephrology and Hypertension, Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee, USA; Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - Dale Abrahamson
- Department of Cell Biology and Physiology, The Jared Grantham Kidney Institute, University of Kansas Medical Center, Kansas City, Kansas, USA
| | - Julie K Hudson
- Aspirnaut, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - Sergei P Boudko
- Division of Nephrology and Hypertension, Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee, USA; Center for Matrix Biology, Vanderbilt University Medical Center, Nashville, Tennessee, USA; Department of Biochemistry, Vanderbilt University, Nashville, Tennessee, USA
| | - Billy G Hudson
- Division of Nephrology and Hypertension, Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee, USA; Aspirnaut, Vanderbilt University Medical Center, Nashville, Tennessee, USA; Center for Matrix Biology, Vanderbilt University Medical Center, Nashville, Tennessee, USA; Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee, USA; Department of Biochemistry, Vanderbilt University, Nashville, Tennessee, USA; Vanderbilt-Ingram Cancer Center, Vanderbilt University, Nashville, Tennessee, USA; Vanderbilt Institute of Chemical Biology, Vanderbilt University, Nashville, Tennessee, USA; Department of Biological Sciences, Vanderbilt University, Nashville, Tennessee, USA; Department of Cell and Developmental Biology, Vanderbilt University, Nashville, Tennessee, USA
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Collier W, Haaland B, Inker L, Greene T. Handling missing within-study correlations in the evaluation of surrogate endpoints. Stat Med 2023; 42:4738-4762. [PMID: 37845797 PMCID: PMC10704210 DOI: 10.1002/sim.9886] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2022] [Revised: 07/16/2023] [Accepted: 08/14/2023] [Indexed: 10/18/2023]
Abstract
Rigorous evaluation of surrogate endpoints is performed in a trial-level analysis in which the strength of the association between treatment effects on the clinical and surrogate endpoints is quantified across a collection of previously conducted trials. To reduce bias in measures of the performance of the surrogate, the statistical model must account for the sampling error in each trial's estimated treatment effects and their potential correlation. Unfortunately, these within-study correlations can be difficult to obtain, especially for meta-analysis of published trial results where individual patient data is not available. As such, these terms are frequently partially or completely missing in the analysis. We show that improper handling of these missing terms can meaningfully alter the perceived quality of the surrogate and we introduce novel strategies to handle the missingness.
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Affiliation(s)
- Willem Collier
- Population and Public Health Sciences, Keck School of Medicine, University of Southern California, CA, United States
- Population Health Sciences, University of Utah School of Medicine, UT, United States
| | - Benjamin Haaland
- Population Health Sciences, University of Utah School of Medicine, UT, United States
| | - Lesley Inker
- Division of Nephrology, Tufts University Medical Center, MA, United States
| | - Tom Greene
- Population Health Sciences, University of Utah School of Medicine, UT, United States
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8
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Divya, Darshna, Sammi A, Chandra P. Design and development of opto-electrochemical biosensing devices for diagnosing chronic kidney disease. Biotechnol Bioeng 2023; 120:3116-3136. [PMID: 37439074 DOI: 10.1002/bit.28490] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2023] [Revised: 06/03/2023] [Accepted: 06/27/2023] [Indexed: 07/14/2023]
Abstract
Chronic kidney disease (CKD) is emerging as one of the major causes of the increase in mortality rate and is expected to become 5th major cause by 2050. Many studies have shown that it is majorly related to various risk factors, and thus becoming one of the major health issues around the globe. Early detection of renal disease lowers the overall burden of disease by preventing individuals from developing kidney impairment. Therefore, diagnosis and prevention of CKD are becoming the major challenges, and in this situation, biosensors have emerged as one of the best possible solutions. Biosensors are becoming one of the preferred choices for various diseases diagnosis as they provide simpler, cost-effective and precise methods for onsite detection. In this review, we have tried to discuss the globally developed biosensors for the detection of CKD, focusing on their design, pattern, and applicability in real samples. Two major classifications of biosensors based on transduction systems, that is, optical and electrochemical, for kidney disease have been discussed in detail. Also, the major focus is given to clinical biomarkers such as albumin, creatinine, and others related to kidney dysfunction. Furthermore, the globally developed sensors for the detection of CKD are discussed in tabulated form comparing their analytical performance, response time, specificity as well as performance in biological fluids.
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Affiliation(s)
- Divya
- Laboratory of Bio-Physio Sensors and Nanobioengineering School of Biochemical Engineering, Indian Institute of Technology (BHU) Varanasi, Varanasi, Uttar Pradesh, India
| | - Darshna
- Laboratory of Bio-Physio Sensors and Nanobioengineering School of Biochemical Engineering, Indian Institute of Technology (BHU) Varanasi, Varanasi, Uttar Pradesh, India
| | - Aditi Sammi
- Laboratory of Bio-Physio Sensors and Nanobioengineering School of Biochemical Engineering, Indian Institute of Technology (BHU) Varanasi, Varanasi, Uttar Pradesh, India
| | - Pranjal Chandra
- Laboratory of Bio-Physio Sensors and Nanobioengineering School of Biochemical Engineering, Indian Institute of Technology (BHU) Varanasi, Varanasi, Uttar Pradesh, India
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9
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Novacescu D, Latcu SC, Bardan R, Daminescu L, Cumpanas AA. Contemporary Biomarkers for Renal Transplantation: A Narrative Overview. J Pers Med 2023; 13:1216. [PMID: 37623466 PMCID: PMC10456039 DOI: 10.3390/jpm13081216] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2023] [Revised: 07/18/2023] [Accepted: 07/28/2023] [Indexed: 08/26/2023] Open
Abstract
Renal transplantation (RT) is the preferred treatment for end-stage renal disease. However, clinical challenges persist, i.e., early detection of graft dysfunction, timely identification of rejection episodes, personalization of immunosuppressive therapy, and prediction of long-term graft survival. Biomarkers have emerged as valuable tools to address these challenges and revolutionize RT patient care. Our review synthesizes the existing scientific literature to highlight promising biomarkers, their biological characteristics, and their potential roles in enhancing clinical decision-making and patient outcomes. Emerging non-invasive biomarkers seemingly provide valuable insights into the immunopathology of nephron injury and allograft rejection. Moreover, we analyzed biomarkers with intra-nephron specificities, i.e., glomerular vs. tubular (proximal vs. distal), which can localize an injury in different nephron areas. Additionally, this paper provides a comprehensive analysis of the potential clinical applications of biomarkers in the prediction, detection, differential diagnosis and assessment of post-RT non-surgical allograft complications. Lastly, we focus on the pursuit of immune tolerance biomarkers, which aims to reclassify transplant recipients based on immune risk thresholds, guide personalized immunosuppression strategies, and ultimately identify patients for whom immunosuppression may safely be reduced. Further research, validation, standardization, and prospective studies are necessary to fully harness the clinical utility of RT biomarkers and guide the development of targeted therapies.
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Affiliation(s)
- Dorin Novacescu
- Doctoral School, Victor Babes University of Medicine and Pharmacy Timisoara, Eftimie Murgu Square, No. 2, 300041 Timisoara, Romania;
| | - Silviu Constantin Latcu
- Doctoral School, Victor Babes University of Medicine and Pharmacy Timisoara, Eftimie Murgu Square, No. 2, 300041 Timisoara, Romania;
- Department of Urology, “Pius Brinzeu” Timisoara County Emergency Hospital, Liviu Rebreanu Boulevard, Nr. 156, 300723 Timisoara, Romania; (R.B.); (L.D.); (A.A.C.)
- Department XV, Discipline of Urology, Victor Babes University of Medicine and Pharmacy Timisoara, Eftimie Murgu Square, No. 2, 300041 Timisoara, Romania
| | - Razvan Bardan
- Department of Urology, “Pius Brinzeu” Timisoara County Emergency Hospital, Liviu Rebreanu Boulevard, Nr. 156, 300723 Timisoara, Romania; (R.B.); (L.D.); (A.A.C.)
- Department XV, Discipline of Urology, Victor Babes University of Medicine and Pharmacy Timisoara, Eftimie Murgu Square, No. 2, 300041 Timisoara, Romania
| | - Liviu Daminescu
- Department of Urology, “Pius Brinzeu” Timisoara County Emergency Hospital, Liviu Rebreanu Boulevard, Nr. 156, 300723 Timisoara, Romania; (R.B.); (L.D.); (A.A.C.)
| | - Alin Adrian Cumpanas
- Department of Urology, “Pius Brinzeu” Timisoara County Emergency Hospital, Liviu Rebreanu Boulevard, Nr. 156, 300723 Timisoara, Romania; (R.B.); (L.D.); (A.A.C.)
- Department XV, Discipline of Urology, Victor Babes University of Medicine and Pharmacy Timisoara, Eftimie Murgu Square, No. 2, 300041 Timisoara, Romania
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10
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Boeckhaus J, Mohr L, Dihazi H, Tönshoff B, Weber LT, Pape L, Latta K, Fehrenbach H, Lange-Sperandio B, Kettwig M, Staude H, König S, John-Kroegel U, Gellermann J, Hoppe B, Galiano M, Haffner D, Rhode H, Gross O. Ratio of Urinary Proteins to Albumin Excretion Shifts Substantially during Progression of the Podocytopathy Alport Syndrome, and Spot Urine Is a Reliable Method to Detect These Pathologic Changes. Cells 2023; 12:cells12091333. [PMID: 37174733 PMCID: PMC10177071 DOI: 10.3390/cells12091333] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2023] [Revised: 04/12/2023] [Accepted: 05/04/2023] [Indexed: 05/15/2023] Open
Abstract
The urinary albumin- and protein-to-creatinine ratios (UACR and UPCR, respectively) are key endpoints in most clinical trials assessing risk of progression of chronic kidney disease (CKD). For the first time, the current study compares the UACR versus the UPCR head-to-head at early stages of CKD, taking use of the hereditary podocytopathy Alport syndrome (AS) as a model disease for any CKD. Urine samples originated from the prospective randomized, controlled EARLY PRO-TECT Alport trial (NCT01485978). Urine samples from 47 children with confirmed diagnoses of AS at very early stages of CKD were divided according to the current stage of AS: stage 0 (UACR < 30 mg/g), stage 1 (30-300 mg/g) or stage 2 (>300 mg/g). The range of estimated glomerular filtration rate was 75-187.6 mL/min. The mean age was 10.4 ± 4.5 years. In children at stage 0, proteinuria in spot urine, confirmed in 24 h urine, was almost ten times higher than albuminuria (106.4 ± 42.2 vs. 12.5 ± 9.7; p < 0.05); it was "only" about three times higher in stage 1 (328.5 ± 210.1 vs. 132.3 ± 80.5; p < 0.05) and almost equal in stage 2 (1481.9 ± 983.4 vs. 1109.7 ± 873.6; p = 0.36). In 17 children, UACRs and UPCRs were measured simultaneously in 24 h urine and spot urine in the same study visit. Interestingly, the UACR (and UPCR) in 24 h urine vs. in spot urine varied by less than 10% (266.8 ± 426.4 vs. 291.2 ± 530.2). In conclusion, our study provides the first evidence that in patients with normal glomerular filtration rate (GFR) and low amounts of albuminuria, especially in children with podocytopathies such as AS, measuring the UACR and UPCR in spot urine is a reliable and convenient alternative to 24 h urine collection. Our study advocates both the UACR and the UPCR as relevant diagnostic biomarkers in future clinical trials in children with glomerular diseases because the UPCR seems to be a very significant parameter at very early stages of podocytopathies. The German Federal Ministry of Education and Research funded this trial (01KG1104).
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Affiliation(s)
- Jan Boeckhaus
- Clinic for Nephrology and Rheumatology, University Medical Center Goettingen, 37075 Goettingen, Germany
| | - Lea Mohr
- Clinic for Nephrology and Rheumatology, University Medical Center Goettingen, 37075 Goettingen, Germany
| | - Hassan Dihazi
- Clinic for Nephrology and Rheumatology, University Medical Center Goettingen, 37075 Goettingen, Germany
| | - Burkhard Tönshoff
- Department of Pediatrics I, University Children's Hospital Heidelberg, 69120 Heidelberg, Germany
| | - Lutz T Weber
- Pediatric Nephrology, Children's and Adolescents' Hospital, Faculty of Medicine and University Hospital Cologne, University of Cologne, 50937 Cologne, Germany
| | - Lars Pape
- Department of Pediatric Kidney, Liver and Metabolic Diseases, Hannover Medical School, 30625 Hannover, Germany
- Department of Pediatrics II, University Childrens' Hospital, University of Duisburg-Essen, 45147 Essen, Germany
| | - Kay Latta
- Clementine Kinderhospital Frankfurt, 60316 Frankfurt, Germany
| | - Henry Fehrenbach
- Pediatric Nephrology, Children's Hospital, 87700 Memmingen, Germany
| | | | - Matthias Kettwig
- Clinic of Pediatrics and Adolescent Medicine, University Medical Center Göttingen, 37075 Göttingen, Germany
| | - Hagen Staude
- Pediatric Nephrology, University Children's Hospital Rostock, 18057 Rostock, Germany
| | - Sabine König
- University Children's Hospital Münster, 48149 Münster, Germany
| | - Ulrike John-Kroegel
- Division of Pediatric Nephrology, University Children's Hospital, 07743 Jena, Germany
| | - Jutta Gellermann
- Pediatric Nephrology, Charité Children's Hospital, 10117 Berlin, Germany
| | - Bernd Hoppe
- Division of Pediatric Nephrology, Department of Pediatrics, University of Bonn, 53121 Bonn, Germany
| | - Matthias Galiano
- Department of Pediatrics and Adolescent Medicine, University Hospital, Friedrich-Alexander-University Erlangen, 91054 Erlangen, Germany
| | - Dieter Haffner
- Department of Pediatric Kidney, Liver and Metabolic Diseases, Hannover Medical School, 30625 Hannover, Germany
| | - Heidrun Rhode
- Department of Internal Medicine I, Cardiology, Angiology, Intensive Medical Care, University Hospital Jena, Am Klinikum 1, 07747 Jena, Germany
| | - Oliver Gross
- Clinic for Nephrology and Rheumatology, University Medical Center Goettingen, 37075 Goettingen, Germany
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11
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Longobardi I, Gualano B, Seguro AC, Roschel H. Is It Time for a Requiem for Creatine Supplementation-Induced Kidney Failure? A Narrative Review. Nutrients 2023; 15:nu15061466. [PMID: 36986197 PMCID: PMC10054094 DOI: 10.3390/nu15061466] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2023] [Revised: 03/13/2023] [Accepted: 03/15/2023] [Indexed: 03/22/2023] Open
Abstract
Creatine has become one of the most popular dietary supplements among a wide range of healthy and clinical populations. However, its potential adverse effects on kidney health are still a matter of concern. This is a narrative review of the effects of creatine supplementation on kidney function. Despite a few case reports and animal studies suggesting that creatine may impair kidney function, clinical trials with controlled designs do not support this claim. Creatine supplementation may increase serum creatinine (Crn) concentration for some individuals, but it does not necessarily indicate kidney dysfunction, as creatine is spontaneously converted into Crn. Based on studies assessing kidney function using reliable methods, creatine supplements have been shown to be safe for human consumption. Further studies with people who have pre-existing kidney disease remain necessary.
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Affiliation(s)
- Igor Longobardi
- Applied Physiology and Nutrition Research Group, School of Physical Education and Sport, School of Medicine, University of Sao Paulo, Sao Paulo 01246-903, SP, Brazil; (I.L.); (B.G.)
| | - Bruno Gualano
- Applied Physiology and Nutrition Research Group, School of Physical Education and Sport, School of Medicine, University of Sao Paulo, Sao Paulo 01246-903, SP, Brazil; (I.L.); (B.G.)
- Rheumatology Division, Hospital das Clinicas HCFMUSP, Faculdade de Medicina, Universidade de São Paulo, Sao Paulo 01246-903, SP, Brazil
| | - Antonio Carlos Seguro
- Nephrology Division, Hospital das Clinicas HCFMUSP, Faculdade de Medicina, Universidade de São Paulo, Sao Paulo 01246-903, SP, Brazil;
| | - Hamilton Roschel
- Applied Physiology and Nutrition Research Group, School of Physical Education and Sport, School of Medicine, University of Sao Paulo, Sao Paulo 01246-903, SP, Brazil; (I.L.); (B.G.)
- Rheumatology Division, Hospital das Clinicas HCFMUSP, Faculdade de Medicina, Universidade de São Paulo, Sao Paulo 01246-903, SP, Brazil
- Correspondence: ; Tel.: +55-11-3061-8789
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12
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Peroxisome proliferator-activated receptor ɣ agonist mediated inhibition of heparanase expression reduces proteinuria. EBioMedicine 2023; 90:104506. [PMID: 36889064 PMCID: PMC10043778 DOI: 10.1016/j.ebiom.2023.104506] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2022] [Revised: 02/16/2023] [Accepted: 02/16/2023] [Indexed: 03/08/2023] Open
Abstract
BACKGROUND Proteinuria is associated with many glomerular diseases and a risk factor for the progression to renal failure. We previously showed that heparanase (HPSE) is essential for the development of proteinuria, whereas peroxisome proliferator-activated receptor ɣ (PPARɣ) agonists can ameliorate proteinuria. Since a recent study showed that PPARɣ regulates HPSE expression in liver cancer cells, we hypothesized that PPARɣ agonists exert their reno-protective effect by inhibiting glomerular HPSE expression. METHODS Regulation of HPSE by PPARɣ was assessed in the adriamycin nephropathy rat model, and cultured glomerular endothelial cells and podocytes. Analyses included immunofluorescence staining, real-time PCR, heparanase activity assay and transendothelial albumin passage assay. Direct binding of PPARɣ to the HPSE promoter was evaluated by the luciferase reporter assay and chromatin immunoprecipitation assay. Furthermore, HPSE activity was assessed in 38 type 2 diabetes mellitus (T2DM) patients before and after 16/24 weeks treatment with the PPARɣ agonist pioglitazone. FINDINGS Adriamycin-exposed rats developed proteinuria, an increased cortical HPSE and decreased heparan sulfate (HS) expression, which was ameliorated by treatment with pioglitazone. In line, the PPARɣ antagonist GW9662 increased cortical HPSE and decreased HS expression, accompanied with proteinuria in healthy rats, as previously shown. In vitro, GW9662 induced HPSE expression in both endothelial cells and podocytes, and increased transendothelial albumin passage in a HPSE-dependent manner. Pioglitazone normalized HPSE expression in adriamycin-injured human endothelial cells and mouse podocytes, and adriamycin-induced transendothelial albumin passage was reduced as well. Importantly, we demonstrated a regulatory effect of PPARɣ on HPSE promoter activity and direct PPARy binding to the HPSE promoter region. Plasma HPSE activity of T2DM patients treated with pioglitazone for 16/24 weeks was related to their hemoglobin A1c and showed a moderate, near significant correlation with plasma creatinine levels. INTERPRETATION PPARɣ-mediated regulation of HPSE expression appears an additional mechanism explaining the anti-proteinuric and renoprotective effects of thiazolidinediones in clinical practice. FUNDING This study was financially supported by the Dutch Kidney Foundation, by grants 15OI36, 13OKS023 and 15OP13. Consortium grant LSHM16058-SGF (GLYCOTREAT; a collaboration project financed by the PPP allowance made available by Top Sector Life Sciences & Health to the Dutch Kidney Foundation to stimulate public-private partnerships).
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13
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Cong Y, Baimanov D, Zhou Y, Chen C, Wang L. Penetration and translocation of functional inorganic nanomaterials into biological barriers. Adv Drug Deliv Rev 2022; 191:114615. [PMID: 36356929 DOI: 10.1016/j.addr.2022.114615] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2022] [Revised: 10/23/2022] [Accepted: 11/02/2022] [Indexed: 11/09/2022]
Abstract
With excellent physicochemical properties, inorganic nanomaterials (INMs) have exhibited a series of attractive applications in biomedical fields. Biological barriers prevent successful delivery of nanomedicine in living systems that limits the development of nanomedicine especially for sufficient delivery of drugs and effective therapy. Numerous researches have focused on overcoming these biological barriers and homogeneity of organisms to enhance therapeutic efficacy, however, most of these strategies fail to resolve these challenges. In this review, we present the latest progress about how INMs interact with biological barriers and penetrate these barriers. We also summarize that both native structure and components of biological barriers and physicochemical properties of INMs contributed to the penetration capacity. Knowledge about the relationship between INMs structure and penetration capacity will guide the design and application of functional and efficient nanomedicine in the future.
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Affiliation(s)
- Yalin Cong
- CAS Key Laboratory for Biomedical Effects of Nanomaterials and Nanosafety, CAS Center for Excellence in Nanoscience, National Center for Nanoscience and Technology of China & Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049, PR China; University of Chinese Academy of Sciences, Beijing 100049, PR China; CAS-HKU Joint Laboratory of Metallomics on Health and Environment, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049, PR China
| | - Didar Baimanov
- CAS Key Laboratory for Biomedical Effects of Nanomaterials and Nanosafety, CAS Center for Excellence in Nanoscience, National Center for Nanoscience and Technology of China & Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049, PR China; University of Chinese Academy of Sciences, Beijing 100049, PR China; CAS-HKU Joint Laboratory of Metallomics on Health and Environment, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049, PR China; Engineering Research Center of Clinical Functional Materials and Diagnosis & Treatment Devices of Zhejiang Province, Wenzhou Institute, University of Chinese Academy of Sciences, Wenzhou 325000, PR China
| | - Yunlong Zhou
- Engineering Research Center of Clinical Functional Materials and Diagnosis & Treatment Devices of Zhejiang Province, Wenzhou Institute, University of Chinese Academy of Sciences, Wenzhou 325000, PR China
| | - Chunying Chen
- CAS Key Laboratory for Biomedical Effects of Nanomaterials and Nanosafety, CAS Center for Excellence in Nanoscience, National Center for Nanoscience and Technology of China & Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049, PR China; University of Chinese Academy of Sciences, Beijing 100049, PR China; GBA Research Innovation Institute for Nanotechnology, Guangzhou 510700, Guangdong, PR China; Research Unit of Nanoscience and Technology, Chinese Academy of Medical Sciences, Beijing 100730, PR China
| | - Liming Wang
- CAS Key Laboratory for Biomedical Effects of Nanomaterials and Nanosafety, CAS Center for Excellence in Nanoscience, National Center for Nanoscience and Technology of China & Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049, PR China; University of Chinese Academy of Sciences, Beijing 100049, PR China; CAS-HKU Joint Laboratory of Metallomics on Health and Environment, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049, PR China.
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14
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Upregulation of OASIS/CREB3L1 in podocytes contributes to the disturbance of kidney homeostasis. Commun Biol 2022; 5:734. [PMID: 35869269 PMCID: PMC9307819 DOI: 10.1038/s42003-022-03709-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2021] [Accepted: 07/12/2022] [Indexed: 12/02/2022] Open
Abstract
Podocyte injury is involved in the onset and progression of various kidney diseases. We previously demonstrated that the transcription factor, old astrocyte specifically induced substance (OASIS) in myofibroblasts, contributes to kidney fibrosis, as a novel role of OASIS in the kidneys. Importantly, we found that OASIS is also expressed in podocytes; however, the pathophysiological significance of OASIS in podocytes remains unknown. Upon lipopolysaccharide (LPS) treatment, there is an increase in OASIS in murine podocytes. Enhanced serum creatinine levels and tubular injury, but not albuminuria and podocyte injury, are attenuated upon podocyte-restricted OASIS knockout in LPS-treated mice, as well as diabetic mice. The protective effects of podocyte-specific OASIS deficiency on tubular injury are mediated by protein kinase C iota (PRKCI/PKCι), which is negatively regulated by OASIS in podocytes. Furthermore, podocyte-restricted OASIS transgenic mice show tubular injury and tubulointerstitial fibrosis, with severe albuminuria and podocyte degeneration. Finally, there is an increase in OASIS-positive podocytes in the glomeruli of patients with minimal change nephrotic syndrome and diabetic nephropathy. Taken together, OASIS in podocytes contributes to podocyte and/or tubular injury, in part through decreased PRKCI. The induction of OASIS in podocytes is a critical event for the disturbance of kidney homeostasis. Upregulation of transcription factor OASIS in podocytes contributes to podocyte and/or tubular injury through decreased PRKCi expression and is a critical event for the disturbance of kidney homeostasis.
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15
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Musiała A, Donizy P, Augustyniak-Bartosik H, Jakuszko K, Banasik M, Kościelska-Kasprzak K, Krajewska M, Kamińska D. Biomarkers in Primary Focal Segmental Glomerulosclerosis in Optimal Diagnostic-Therapeutic Strategy. J Clin Med 2022; 11:jcm11123292. [PMID: 35743361 PMCID: PMC9225193 DOI: 10.3390/jcm11123292] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2022] [Revised: 06/02/2022] [Accepted: 06/06/2022] [Indexed: 02/01/2023] Open
Abstract
Focal segmental glomerulosclerosis (FSGS) involves podocyte injury. In patients with nephrotic syndrome, progression to end-stage renal disease often occurs over the course of 5 to 10 years. The diagnosis is based on a renal biopsy. It is presumed that primary FSGS is caused by an unknown plasma factor that might be responsible for the recurrence of FSGS after kidney transplantation. The nature of circulating permeability factors is not explained and particular biological molecules responsible for inducing FSGS are still unknown. Several substances have been proposed as potential circulating factors such as soluble urokinase-type plasminogen activator receptor (suPAR) and cardiolipin-like-cytokine 1 (CLC-1). Many studies have also attempted to establish which molecules are related to podocyte injury in the pathogenesis of FSGS such as plasminogen activator inhibitor type-1 (PAI-1), angiotensin II type 1 receptors (AT1R), dystroglycan(DG), microRNAs, metalloproteinases (MMPs), forkheadbox P3 (FOXP3), and poly-ADP-ribose polymerase-1 (PARP1). Some biomarkers have also been studied in the context of kidney tissue damage progression: transforming growth factor-beta (TGF-β), human neutrophil gelatinase-associated lipocalin (NGAL), malondialdehyde (MDA), and others. This paper describes molecules that could potentially be considered as circulating factors causing primary FSGS.
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Affiliation(s)
- Aleksandra Musiała
- Department of Nephrology and Transplantation Medicine, Wroclaw Medical University, 50-556 Wroclaw, Poland; (H.A.-B.); (K.J.); (M.B.); (K.K.-K.); (M.K.); (D.K.)
- Correspondence: ; Tel.: +48-6-0172-8231
| | - Piotr Donizy
- Department of Clinical and Experimental Pathology, Division of Clinical Pathology, Wroclaw Medical University, 50-556 Wroclaw, Poland;
| | - Hanna Augustyniak-Bartosik
- Department of Nephrology and Transplantation Medicine, Wroclaw Medical University, 50-556 Wroclaw, Poland; (H.A.-B.); (K.J.); (M.B.); (K.K.-K.); (M.K.); (D.K.)
| | - Katarzyna Jakuszko
- Department of Nephrology and Transplantation Medicine, Wroclaw Medical University, 50-556 Wroclaw, Poland; (H.A.-B.); (K.J.); (M.B.); (K.K.-K.); (M.K.); (D.K.)
| | - Mirosław Banasik
- Department of Nephrology and Transplantation Medicine, Wroclaw Medical University, 50-556 Wroclaw, Poland; (H.A.-B.); (K.J.); (M.B.); (K.K.-K.); (M.K.); (D.K.)
| | - Katarzyna Kościelska-Kasprzak
- Department of Nephrology and Transplantation Medicine, Wroclaw Medical University, 50-556 Wroclaw, Poland; (H.A.-B.); (K.J.); (M.B.); (K.K.-K.); (M.K.); (D.K.)
| | - Magdalena Krajewska
- Department of Nephrology and Transplantation Medicine, Wroclaw Medical University, 50-556 Wroclaw, Poland; (H.A.-B.); (K.J.); (M.B.); (K.K.-K.); (M.K.); (D.K.)
| | - Dorota Kamińska
- Department of Nephrology and Transplantation Medicine, Wroclaw Medical University, 50-556 Wroclaw, Poland; (H.A.-B.); (K.J.); (M.B.); (K.K.-K.); (M.K.); (D.K.)
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16
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Jin J, Li Y, Zhu Y, Ni J. A single center, retrospective chart review of associations between cessation of second-line therapies and relapse rates of childhood refractory minimal change nephrotic syndrome. Curr Ther Res Clin Exp 2022; 96:100671. [PMID: 35574245 PMCID: PMC9092853 DOI: 10.1016/j.curtheres.2022.100671] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2021] [Accepted: 04/07/2022] [Indexed: 11/16/2022] Open
Affiliation(s)
| | - Yufeng Li
- Address correspondence to: Yu-Feng Li, MD, PhD, Department of Pediatric Nephrology, Rheumatology, and Immunology, Xinhua Hospital Affiliated to Shanghai Jiaotong University School of Medicine, No.1665, Kongjiang Rd, Yangpu District, Shanghai 200092, China.
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17
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Liang S, Luo D, Hu L, Fang M, Li J, Deng J, Fang H, Zhang H, He L, Xu J, Liang Y, Chen C. Variations of urinary N-acetyl-β-D-glucosaminidase levels and its performance in detecting acute kidney injury under different thyroid hormones levels: a prospectively recruited, observational study. BMJ Open 2022; 12:e055787. [PMID: 35241468 PMCID: PMC8896032 DOI: 10.1136/bmjopen-2021-055787] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
OBJECTIVE Changes in thyroid function will be accompanied by changes in urinary N-acetyl-β-D-glucosaminidase (uNAG) levels. Therefore, whether thyroid hormones interfere the ability of uNAG in detecting acute kidney injury (AKI) has raised concern in patients with critical illness. DESIGN A prospectively recruited, observational study was performed. SETTING Adults admitted to the intensive care unit of a grade A tertiary hospital in China. PARTICIPANTS A total of 1919 critically ill patients were enrolled in the study. MAIN OUTCOME MEASURES To investigate the variations of the ability of uNAG to detect AKI in patients with critical illness under different thyroid hormones levels (differences in area under the curve (AUC) for uNAG diagnosis and prediction of AKI with different thyroid hormones levels). RESULTS The bivariate correlation analysis revealed that FT3 and TT3 levels were independently associated with uNAG levels (p<0.001). FT3 and uNAG also showed correlation in multivariable linear regression analysis (p<0.001). After stratification according to the levels of FT3 or TT3, significant variation was observed in the uNAG levels with different quartiles (p<0.05). However, in patients with varying FT3 and TT3 levels, no significant difference was found in the AUCs of uNAG to detect AKI (p>0.05). CONCLUSIONS Even if uNAG levels varied with FT3 and TT3 levels, these hormones did not interfere with uNAG's ability to detect AKI in patients with critical illness.
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Affiliation(s)
- Silin Liang
- Department of Intensive Care Unit of Cardiovascular Surgery, Guangdong Cardiovascular Institute, Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences, 96 Dongchuan Road, Guangzhou 510080, Guangdong Province, People's Republic of China
- Department of Critical Care Medicine, Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences, 106 Zhongshan Er Road, Guangzhou 510080, Guangdong Province, People's Republic of China
| | - Dandong Luo
- Department of Intensive Care Unit of Cardiovascular Surgery, Guangdong Cardiovascular Institute, Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences, 96 Dongchuan Road, Guangzhou 510080, Guangdong Province, People's Republic of China
| | - Linhui Hu
- Department of Critical Care Medicine, Maoming People's Hospital, 101 Weimin Road, Maoming 525000, Guangdong Province, People's Republic of China
- Center of Scientific Research, Maoming People's Hospital, 101 Weimin Road, Maoming 525000, Guangdong Province, People's Republic of China
| | - Miaoxian Fang
- Department of Intensive Care Unit of Cardiovascular Surgery, Guangdong Cardiovascular Institute, Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences, 96 Dongchuan Road, Guangzhou 510080, Guangdong Province, People's Republic of China
| | - Jiaxin Li
- Department of Intensive Care Unit of Cardiovascular Surgery, Guangdong Cardiovascular Institute, Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences, 96 Dongchuan Road, Guangzhou 510080, Guangdong Province, People's Republic of China
| | - Jia Deng
- Department of Intensive Care Unit of Cardiovascular Surgery, Guangdong Cardiovascular Institute, Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences, 96 Dongchuan Road, Guangzhou 510080, Guangdong Province, People's Republic of China
- Department of Critical Care Medicine, Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences, 106 Zhongshan Er Road, Guangzhou 510080, Guangdong Province, People's Republic of China
| | - Heng Fang
- Department of Intensive Care Unit of Cardiovascular Surgery, Guangdong Cardiovascular Institute, Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences, 96 Dongchuan Road, Guangzhou 510080, Guangdong Province, People's Republic of China
- Department of Critical Care Medicine, Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences, 106 Zhongshan Er Road, Guangzhou 510080, Guangdong Province, People's Republic of China
| | - Huidan Zhang
- Department of Intensive Care Unit of Cardiovascular Surgery, Guangdong Cardiovascular Institute, Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences, 96 Dongchuan Road, Guangzhou 510080, Guangdong Province, People's Republic of China
- Department of Critical Care Medicine, Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences, 106 Zhongshan Er Road, Guangzhou 510080, Guangdong Province, People's Republic of China
| | - Linling He
- Department of Intensive Care Unit of Cardiovascular Surgery, Guangdong Cardiovascular Institute, Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences, 96 Dongchuan Road, Guangzhou 510080, Guangdong Province, People's Republic of China
- Department of Critical Care Medicine, Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences, 106 Zhongshan Er Road, Guangzhou 510080, Guangdong Province, People's Republic of China
| | - Jing Xu
- Department of Intensive Care Unit of Cardiovascular Surgery, Guangdong Cardiovascular Institute, Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences, 96 Dongchuan Road, Guangzhou 510080, Guangdong Province, People's Republic of China
- Department of Critical Care Medicine, Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences, 106 Zhongshan Er Road, Guangzhou 510080, Guangdong Province, People's Republic of China
| | - Yufan Liang
- Department of Critical Care Medicine, Maoming People's Hospital, 101 Weimin Road, Maoming 525000, Guangdong Province, People's Republic of China
- Center of Scientific Research, Maoming People's Hospital, 101 Weimin Road, Maoming 525000, Guangdong Province, People's Republic of China
| | - Chunbo Chen
- Department of Intensive Care Unit of Cardiovascular Surgery, Guangdong Cardiovascular Institute, Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences, 96 Dongchuan Road, Guangzhou 510080, Guangdong Province, People's Republic of China
- Department of Critical Care Medicine, Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences, 106 Zhongshan Er Road, Guangzhou 510080, Guangdong Province, People's Republic of China
- The Second School of Clinical Medicine, Southern Medical University, Guangzhou, Guangdong Province, People's Republic of China
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18
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Neonatal Proteinuria in Calves-A Quantitative Approach. Animals (Basel) 2021; 11:ani11123602. [PMID: 34944377 PMCID: PMC8698049 DOI: 10.3390/ani11123602] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2021] [Revised: 12/16/2021] [Accepted: 12/17/2021] [Indexed: 11/16/2022] Open
Abstract
Simple Summary A newborn’s survival depends on the quick adaptation of the organism to new environmental conditions. Newborn calves show high somatic maturity compared to, for example, human newborns, but their body functions with a lower efficiency than that of adult cattle. Adaptation processes concern all organs, including the kidneys, which are not morphologically mature after birth. The ongoing morphological changes imply functional alterations in the kidneys. There is an increase in blood flow through the kidneys and the glomerular filtration rate, as well as an increase in the efficiency of resorption processes of primary urine components into the blood, including proteins. Protein is present in trace amounts in the urine of healthy adults of various species. It can occur in larger amounts in the urine of sick animals, as well as in certain physiological states, e.g., in newborns. The presence of protein in the urine of newborns in the quantity exceeding 300 mg/24 h/m2 is called neonatal proteinuria. The causes of proteinuria in healthy newborns have not been clearly elucidated. Many studies have focused on proteinuria in newborns and sick children and sick animals, especially dogs and cats. The present study was the first to quantify the hypothesis of the occurrence of proteinuria in healthy calves in the first week of life and to assess its intensity and dynamics, based on the analysis of changes in total protein excretion in the urine and its fractions differing in molecular weight (albumin, low molecular weight proteins (LMW) and high molecular weight proteins (HMW)). It should be noted that the analysis of excreted protein fractions is a sensitive diagnostic indicator of the type of kidney disease, e.g., increased HMW protein excretion may indicate damage to the renal glomeruli, and loss of LMW proteins may indicate renal tubular disease. Abstract Urine testing is a convenient, non-invasive method of obtaining information about body functions. Depending on the intended purpose, urine testing may be qualitative and/or quantitative. Urine analysis can also include proteins. There are no data in the literature on the occurrence of proteinuria in healthy neonatal calves. The present study was the first that aimed to quantify the hypothesis of proteinuria occurrence in these animals in the first week of life, to assess its intensity and dynamics and to understand the underlying causes of proteinuria in healthy calves. The research was carried out on 15 healthy calves in the first seven days of life. Calves were catheterized to determine minute diuresis. Total protein concentration was determined in blood plasma and urine. Urine proteins were separated by electrophoresis (SDSPAGE) and their concentration and percentage were determined by densitometry using an image archiving and analysis software. The separated proteins were divided into three groups according to molecular weight for albumin, LMW and HMW proteins. The results were standardized per 1 m2 of body surface area and statistically analyzed. Neonatal proteinuria was demonstrated in healthy calves, mainly resulting from the high concentration of LMW proteins in the urine. Their percentages decreased significantly from 84.46% on the first day of calves’ life to 64.02% on day 7. At the same time, a statistically significant increase was observed in the proportion of albumin and high molecular weight proteins in urine total protein. Albumin percentage increased from 9.54% (on day 1) to almost 20% (on day 7), while the proportion of HMW proteins increased from 6.68% to 18.13%, respectively. The concentration of total protein in the urine of newborn calves amounted to 14.64 g/L and decreased statistically significantly during the first 72 h of postnatal life, stabilizing at the level of 3–4 g/L. The mean value of total protein excretion in the first week of life was 4.81 mg/min/m2 (i.e., 6.93 g/24 h/m2). The analysis of protein concentration in the urine and its excretion, as well as changes in urinary excretion of the tested protein fractions, indicated that neonatal proteinuria in healthy neonatal calves was tubular (i.e., main reason is the reduced absorption of proteins in nephrons). In addition, research showed that there was a rapid improvement in resorptive mechanisms in tubular cells. It should be assumed that the filtration barrier in the kidneys of these animals after birth is morphologically prepared to retain high molecular weight proteins. It seems that the increased permeability of the filtration barrier in the glomeruli does not necessarily indicate the immaturity of the kidneys, but may indicate the kidneys’ adaptation to excess protein removal from the body during feeding with high-protein food (colostrum), with an open intestinal barrier enabling protein absorption from the gastrointestinal tract to the blood.
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Jeon J, Kim J. Dipstick proteinuria and risk of type 2 diabetes mellitus: a nationwide population-based cohort study. J Transl Med 2021; 19:271. [PMID: 34174896 PMCID: PMC8235563 DOI: 10.1186/s12967-021-02934-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Accepted: 06/09/2021] [Indexed: 12/17/2022] Open
Abstract
Background Proteinuria has been recognized as a marker of systemic inflammation and endothelial dysfunction associated with insulin resistance and β-cell impairment, which can contribute to the development of type 2 diabetes mellitus (T2DM). However, it is unknown whether the dipstick proteinuria test has a predictive value for new-onset T2DM. Methods This retrospective cohort study analyzed 239,287 non-diabetic participants who participated in the Korean nationwide health screening program in 2009–2010. Proteinuria was determined by the urine dipstick test at the baseline health screening. We performed multivariate Cox proportional regression analyses for the development of new-onset T2DM. Follow-up was performed until December 2015. Results During the mean follow-up period of 5.73 years, 22,215 participants were diagnosed with new-onset T2DM. The presence of proteinuria was significantly associated with an increased risk of T2DM (adjusted hazard ratio: 1.19, 95% confidence interval: 1.10, 1.29). There was a positive dose–response relationship between the degree of dipstick proteinuria and T2DM risk. This significant association between proteinuria and T2DM risk was consistent regardless of the fasting glucose level at baseline. Conclusions Dipstick proteinuria is a significant risk factor for new-onset T2DM. Therefore, proteinuria might be a useful biomarker to identify those at a high risk for developing T2DM. Supplementary Information The online version contains supplementary material available at 10.1186/s12967-021-02934-y.
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Affiliation(s)
- Jimin Jeon
- Department of Neurology, Yongin Severance Hospital, Yonsei University College of Medicine, 363, Dongbaekjukjeon-daero, Giheung-gu, Yongin, 16995, Republic of Korea
| | - Jinkwon Kim
- Department of Neurology, Yongin Severance Hospital, Yonsei University College of Medicine, 363, Dongbaekjukjeon-daero, Giheung-gu, Yongin, 16995, Republic of Korea.
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Sharma S, Smyth B. From Proteinuria to Fibrosis: An Update on Pathophysiology and Treatment Options. Kidney Blood Press Res 2021; 46:411-420. [PMID: 34130301 DOI: 10.1159/000516911] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2020] [Accepted: 04/28/2021] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Proteinuria is a key biomarker in nephrology. It is central to diagnosis and risk assessment and the primary target of many important therapies. Etiologies resulting in pathological proteinuria include congenital and acquired disorders, as well as both glomerular (immune/non-immune mediated) and tubular defects. SUMMARY Untreated proteinuria is strongly linked to progressive loss of kidney function and kidney failure. Excess protein reaching the renal tubules is ordinarily resorbed by the tubular epithelium. However, when these mechanisms are overwhelmed, a variety of inflammatory and fibrotic pathways are activated, causing both interstitial fibrosis and glomerulosclerosis. Nevertheless, the specific mechanisms underlying this are complex and remain incompletely understood. Recently, a number of treatments, in addition to angiotensin system blockade, have been shown to effectively slow the progression of proteinuric chronic kidney disease. However, additional therapies are clearly needed. Key message: This review provides an update on the pathophysiology of proteinuria, the pathways leading to fibrosis, and an overview of current and emerging therapies.
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Affiliation(s)
- Sonia Sharma
- Department of Pediatric Nephrology, Fortis Hospital, Shalimar-Bagh, New Delhi, India
| | - Brendan Smyth
- Department of Renal Medicine, St. George Hospital, Sydney, New South Wales, Australia
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Reconsidering Garth Robinson: fluid flow and the glomerular filtration barrier. Curr Opin Nephrol Hypertens 2020; 29:273-279. [PMID: 32235269 DOI: 10.1097/mnh.0000000000000606] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
PURPOSE OF REVIEW The goal of this review is to present recent models of the filtration barrier that may suggest mechanism-based treatments for proteinuric renal disease. The vast majority of renal failure occurs in diseases of glomerular proteinuria. The physiology of the filtration barrier remains incompletely understood, preventing invention of mechanism-based therapies. Research is currently dominated by molecular biology approaches to the kidney instead of engineering-based filtration and transport models. RECENT FINDINGS Reexamination of two older paradigms (basement membrane and slit diaphragm) and critical analysis of newer models may provide mechanistic insight to guide further research. We expand on our theory of podocyte-basement membrane mechanical interactions and speculate on mechanisms of action of the leading treatment for proteinuria, angiotensin blockade. SUMMARY Treatment of proteinuria remains largely empiric and based on inhibition of the renin-angiotensin-aldosterone system, with additional benefit from statins and vitamin D. Improved definition of transport phenomena in the capillary wall may suggest rational design of new interventions.
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Kawachi H, Fukusumi Y. New insight into podocyte slit diaphragm, a therapeutic target of proteinuria. Clin Exp Nephrol 2020; 24:193-204. [PMID: 32020343 PMCID: PMC7040068 DOI: 10.1007/s10157-020-01854-3] [Citation(s) in RCA: 69] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2019] [Accepted: 01/15/2020] [Indexed: 12/26/2022]
Abstract
Dysfunction of slit diaphragm, a cell–cell junction of glomerular podocytes, is involved in the development of proteinuria in several glomerular diseases. Slit diaphragm should be a target of a novel therapy for proteinuria. Nephrin, NEPH1, P-cadherin, FAT, and ephrin-B1 were reported to be extracellular components forming a molecular sieve of the slit diaphragm. Several cytoplasmic proteins such as ZO-1, podocin, CD2AP, MAGI proteins and Par-complex molecules were identified as scaffold proteins linking the slit diaphragm to the cytoskeleton. In this article, new insights into these molecules and the pathogenic roles of the dysfunction of these molecules were introduced. The slit diaphragm functions not only as a barrier but also as a signaling platform transfer the signal to the inside of the cell. For maintaining the slit diaphragm function properly, the phosphorylation level of nephrin is strictly regulated. The recent studies on the signaling pathway from nephrin, NEPH1, and ephrin-B1 were reviewed. Although the mechanism regulating the function of the slit diaphragm had remained unclear, recent studies revealed TRPC6 and angiotensin II-regulating mechanisms play a critical role in regulating the barrier function of the slit diaphragm. In this review, recent investigations on the regulation of the slit diaphragm function were reviewed, and a strategy for the establishment of a novel therapy for proteinuria was proposed.
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Affiliation(s)
- Hiroshi Kawachi
- Department of Cell Biology, Kidney Research Center, Niigata University Graduate School of Medical and Dental Sciences, 1-757 Asahimachi-dori, Chuo-ku, Niigata, 951-8510, Japan.
| | - Yoshiyasu Fukusumi
- Department of Cell Biology, Kidney Research Center, Niigata University Graduate School of Medical and Dental Sciences, 1-757 Asahimachi-dori, Chuo-ku, Niigata, 951-8510, Japan
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Alghadban S, Kenawy HI, Dudler T, Schwaeble WJ, Brunskill NJ. Absence of the Lectin Activation Pathway of Complement Ameliorates Proteinuria-Induced Renal Injury. Front Immunol 2019; 10:2238. [PMID: 31608060 PMCID: PMC6768126 DOI: 10.3389/fimmu.2019.02238] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2019] [Accepted: 09/04/2019] [Indexed: 12/15/2022] Open
Abstract
Proteinuria is an adverse prognostic feature in renal diseases. In proteinuric nephropathies, filtered proteins exert an injurious effect on the renal tubulointerstitium, resulting in inflammation and fibrosis. In the present study, we assessed to what extent complement activation via the lectin pathway may contribute to renal injury in response to proteinuria-related stress in proximal tubular cells. We used the well-established mouse model of protein overload proteinuria (POP) to assess the effect of lectin pathway inhibition on renal injury and fibrotic changes characteristic of proteinuric nephropathy. To this end, we compared experimental outcomes in wild type mice with MASP-2-deficient mice or wild type mice treated with MASP-2 inhibitor to block lectin pathway functional activity. Multiple markers of renal injury were assessed including renal function, proteinuria, macrophage infiltration, and cytokine release profiles. Both MASP-2-deficient and MASP-2 inhibitor-treated wild type mice exhibited renoprotection from proteinuria with significantly less tubulointerstitial injury when compared to isotype control antibody treated mice. This indicates that therapeutic targeting of MASP-2 in proteinuric nephropathies may offer a useful strategy in the clinical management of proteinuria associated pathologies in a variety of different underlying renal diseases.
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Affiliation(s)
- Samy Alghadban
- Department of Infection, Immunity and Inflammation, College of Life Sciences, University of Leicester, Leicester, United Kingdom.,Zoology Department, Faculty of Science, Al-Azhar University, Cairo, Egypt
| | - Hany I Kenawy
- Department of Infection, Immunity and Inflammation, College of Life Sciences, University of Leicester, Leicester, United Kingdom.,Microbiology and Immunology Department, Faculty of Pharmacy, Mansoura University, Mansoura, Egypt
| | | | - Wilhelm J Schwaeble
- Department of Infection, Immunity and Inflammation, College of Life Sciences, University of Leicester, Leicester, United Kingdom.,Department of Veterinary Medicine, University of Cambridge, Cambridge, United Kingdom
| | - Nigel J Brunskill
- Department of Infection, Immunity and Inflammation, College of Life Sciences, University of Leicester, Leicester, United Kingdom.,Department of Nephrology, Leicester General Hospital, Leicester, United Kingdom
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Heerspink HJL, Greene T, Tighiouart H, Gansevoort RT, Coresh J, Simon AL, Chan TM, Hou FF, Lewis JB, Locatelli F, Praga M, Schena FP, Levey AS, Inker LA. Change in albuminuria as a surrogate endpoint for progression of kidney disease: a meta-analysis of treatment effects in randomised clinical trials. Lancet Diabetes Endocrinol 2019; 7:128-139. [PMID: 30635226 DOI: 10.1016/s2213-8587(18)30314-0] [Citation(s) in RCA: 209] [Impact Index Per Article: 41.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/05/2018] [Revised: 10/22/2018] [Accepted: 10/23/2018] [Indexed: 01/10/2023]
Abstract
BACKGROUND Change in albuminuria has strong biological plausibility as a surrogate endpoint for progression of chronic kidney disease, but empirical evidence to support its validity is lacking. We aimed to determine the association between treatment effects on early changes in albuminuria and treatment effects on clinical endpoints and surrograte endpoints, to inform the use of albuminuria as a surrogate endpoint in future randomised controlled trials. METHODS In this meta-analysis, we searched PubMed for publications in English from Jan 1, 1946, to Dec 15, 2016, using search terms including "chronic kidney disease", "chronic renal insufficiency", "albuminuria", "proteinuria", and "randomized controlled trial"; key inclusion criteria were quantifiable measurements of albuminuria or proteinuria at baseline and within 12 months of follow-up and information on the incidence of end-stage kidney disease. We requested use of individual patient data from the authors of eligible studies. For all studies that the authors agreed to participate and that had sufficient data, we estimated treatment effects on 6-month change in albuminuria and the composite clinical endpoint of treated end-stage kidney disease, estimated glomerular filtration rate of less than 15 mL/min per 1·73 m2, or doubling of serum creatinine. We used a Bayesian mixed-effects meta-regression analysis to relate the treatment effects on albuminuria to those on the clinical endpoint across studies and developed a prediction model for the treatment effect on the clinical endpoint on the basis of the treatment effect on albuminuria. FINDINGS We identified 41 eligible treatment comparisons from randomised trials (referred to as studies) that provided sufficient patient-level data on 29 979 participants (21 206 [71%] with diabetes). Over a median follow-up of 3·4 years (IQR 2·3-4·2), 3935 (13%) participants reached the composite clinical endpoint. Across all studies, with a meta-regression slope of 0·89 (95% Bayesian credible interval [BCI] 0·13-1·70), each 30% decrease in geometric mean albuminuria by the treatment relative to the control was associated with an average 27% lower hazard for the clinical endpoint (95% BCI 5-45%; median R2 0·47, 95% BCI 0·02-0·96). The association strengthened after restricting analyses to patients with baseline albuminuria of more than 30 mg/g (ie, 3·4 mg/mmol; R2 0·72, 0·05-0·99]). For future trials, the model predicts that treatments that decrease the geometric mean albuminuria to 0·7 (ie, 30% decrease in albuminuria) relative to the control will provide an average hazard ratio (HR) for the clinical endpoint of 0·68, and 95% of sufficiently large studies would have HRs between 0·47 and 0·95. INTERPRETATION Our results support a role for change in albuminuria as a surrogate endpoint for the progression of chronic kidney disease, particularly in patients with high baseline albuminuria; for patients with low baseline levels of albuminuria this association is less certain. FUNDING US National Kidney Foundation.
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Affiliation(s)
- Hiddo J L Heerspink
- Department of Clinical Pharmacy and Pharmacology, University of Groningen, University Medical Center Groningen, Groningen, Netherlands
| | - Tom Greene
- Division of Epidemiology, Department of Internal Medicine, University of Utah, Salt Lake City, UT, USA
| | - Hocine Tighiouart
- Institute for Clinical Research and Health Policy Studies, Boston, MA, USA; Tufts Medical Center, Boston, MA, USA; Tufts Clinical and Translational Science Institute, Tufts University, Boston, MA, USA
| | - Ron T Gansevoort
- Department of Nephrology, University of Groningen, University Medical Center Groningen, Groningen, Netherlands
| | - Josef Coresh
- Department of Epidemiology, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA
| | | | - Tak Mao Chan
- Department of Medicine, University of Hong Kong, Queen Mary Hospital, Pokfulam, Hong Kong
| | - Fan Fan Hou
- Division of Nephrology, Nanfang Hospital, Southern Medical University, Guangzhou, China
| | - Julia B Lewis
- Division of Nephrology, Vanderbilt University, Nashville, TN, USA
| | - Francesco Locatelli
- Department of Nephrology and Dialysis, Hospital Alessandro Manzoni, Lecco, Italy
| | - Manuel Praga
- Nephrology Department, Hospital Universitario 12 de Octubre, Madrid, Spain
| | - Francesco Paolo Schena
- Renal, Dialysis and Transplant Unit, Department of Emergency and Organ Transplantation, University of Bari, Bari, Italy
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Sodium bicarbonate loading limits tubular cast formation independent of glomerular injury and proteinuria in Dahl salt-sensitive rats. Clin Sci (Lond) 2018; 132:1179-1197. [PMID: 29650676 DOI: 10.1042/cs20171630] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2017] [Revised: 04/10/2018] [Accepted: 04/12/2018] [Indexed: 11/17/2022]
Abstract
Sodium bicarbonate (NaHCO3) slows the decline in kidney function in patients with chronic kidney disease (CKD), yet the mechanisms mediating this effect remain unclear. The Dahl salt-sensitive (SS) rat develops hypertension and progressive renal injury when fed a high salt diet; however, the effect of alkali loading on kidney injury has never been investigated in this model. We hypothesized that NaHCO3 protects from the development of renal injury in Dahl salt-sensitive rats via luminal alkalization which limits the formation of tubular casts, which are a prominent pathological feature in this model. To examine this hypothesis, we determined blood pressure and renal injury responses in Dahl SS rats drinking vehicle (0.1 M NaCl) or NaHCO3 (0.1 M) solutions as well as in Dahl SS rats lacking the voltage-gated proton channel (Hv1). We found that oral NaHCO3 reduced tubular NH4+ production, tubular cast formation, and interstitial fibrosis in rats fed a high salt diet for 2 weeks. This effect was independent of changes in blood pressure, glomerular injury, or proteinuria and did not associate with changes in renal inflammatory status. We found that null mutation of Hv1 also limited cast formation in Dahl SS rats independent of proteinuria or glomerular injury. As Hv1 is localized to the luminal membrane of TAL, our data suggest that alkalization of the luminal fluid within this segment limits cast formation in this model. Reduced cast formation, secondary to luminal alkalization within TAL segments may mediate some of the protective effects of alkali loading observed in CKD patients.
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Restless legs syndrome: a rarity in the Nigerian pregnant population? Sleep Med 2018; 43:47-53. [PMID: 29482812 DOI: 10.1016/j.sleep.2018.01.002] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/06/2017] [Revised: 12/15/2017] [Accepted: 01/04/2018] [Indexed: 11/23/2022]
Abstract
OBJECTIVES The prevalence of RLS in pregnancy is higher when compared with the general population however it remains unknown among indigenous black Africans. Available data indicate that RLS is uncommon in sub-Saharan Africa. We embarked on this study to determine the prevalence and characteristics of RLS in an antenatal clinic sample of Nigerian pregnant women compared with a primary care sample of non-pregnant women. METHODS A total of 310 pregnant women and non-pregnant women filled out a questionnaire which incorporated the 2014 minimal criteria of the International Restless Legs Syndrome Study Group. Demographic and clinical data, including sleep duration and samples for blood hemoglobin concentration and urinalysis were obtained. RESULTS The mean ages of the pregnant and non-pregnant women were 24.9 ± 5.6 years and 23.6 + 5.4 years, respectively (p = 0.003). There was no case of RLS found among pregnant women while five (1.6%) of the non-pregnant women fulfilled the criteria for RLS. Overall, the prevalence report of RLS symptoms was associated with lower mean habitual nocturnal sleep duration (p < 0.05) coffee (p = 0.013) and kola nut (0.023) consumption, report of leg cramps (p < 0.001) and proteinuria (p = 0.047), Report of leg cramps and proteinuria were independently associated with RLS. CONCLUSION The prevalence of restless legs syndrome is low among women of child-bearing age in the Nigerian population and may be lower in pregnancy. Report of leg cramps and proteinuria are independently associated with RLS.
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Yamazaki M, Fukusumi Y, Kayaba M, Kitazawa Y, Takamura S, Narita I, Kawachi H. Possible role for glomerular-derived angiotensinogen in nephrotic syndrome. J Renin Angiotensin Aldosterone Syst 2016; 17:17/4/1470320316681223. [PMID: 27932705 PMCID: PMC5843942 DOI: 10.1177/1470320316681223] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2016] [Accepted: 10/28/2016] [Indexed: 01/13/2023] Open
Abstract
Background and objective: Renin–angiotensin system (RAS) inhibitors reduce glomerular injury and proteinuria, indicating that angiotensin II (Ang II) is involved in glomerular diseases. Although the local RAS is reported to play an essential role in maintaining local tissue functions, the role of the local RAS in regulating glomerular function is not well evaluated. In this study, we analyzed the glomerular expression of RAS components in nephrotic models and the effect of Ang II receptor blockers (ARB) on the expression of angiotensinogen (AGT). Methods: The levels of glomerular expression of RAS components were analyzed in two nephrotic models: anti-nephrin antibody-induced nephropathy and PAN nephropathy, a mimic of human minimal change nephrotic syndrome. The effect of the ARB irbesartan on the expression of AGT in the nephrotic model was analyzed. Results: Glomerular expression of AGT and the receptors for Ang II was clearly increased in the nephrotic models, while the expression levels of renin, ACE and ACE2 were decreased. ARB treatment suppressed the increase of glomerular expression of AGT in the nephrotic model. Conclusion: It is conceivable that the promoted local RAS action participated in the glomerular dysfunction, and that ARB treatment ameliorated slit diaphragm injury by inhibiting the positive feedback loop of the activated local Ang II action.
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Affiliation(s)
- Mihoko Yamazaki
- Department of Cell Biology, Kidney Research Center, Niigata University Graduate School of Medical and Dental Sciences, Japan.,Department of Nephrology and Rheumatology, Kidney Research Center, Niigata University Graduate School of Medical and Dental Sciences, Japan
| | - Yoshiyasu Fukusumi
- Department of Cell Biology, Kidney Research Center, Niigata University Graduate School of Medical and Dental Sciences, Japan
| | - Mutsumi Kayaba
- Department of Cell Biology, Kidney Research Center, Niigata University Graduate School of Medical and Dental Sciences, Japan
| | - Yukina Kitazawa
- Department of Cell Biology, Kidney Research Center, Niigata University Graduate School of Medical and Dental Sciences, Japan
| | - Sayuri Takamura
- Department of Cell Biology, Kidney Research Center, Niigata University Graduate School of Medical and Dental Sciences, Japan
| | - Ichiei Narita
- Department of Nephrology and Rheumatology, Kidney Research Center, Niigata University Graduate School of Medical and Dental Sciences, Japan
| | - Hiroshi Kawachi
- Department of Cell Biology, Kidney Research Center, Niigata University Graduate School of Medical and Dental Sciences, Japan
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Comparison of the Efficacy of Tacrolimus Versus Cyclosporine in the Treatment of Idiopathic Membranous Nephropathy. Nephrourol Mon 2016. [DOI: 10.5812/numonthly.42473] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
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Cathepsin L is crucial for the development of early experimental diabetic nephropathy. Kidney Int 2016; 90:1012-1022. [DOI: 10.1016/j.kint.2016.06.035] [Citation(s) in RCA: 49] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2015] [Revised: 06/22/2016] [Accepted: 06/30/2016] [Indexed: 11/20/2022]
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Mori KP, Yokoi H, Kasahara M, Imamaki H, Ishii A, Kuwabara T, Koga K, Kato Y, Toda N, Ohno S, Kuwahara K, Endo T, Nakao K, Yanagita M, Mukoyama M, Mori K. Increase of Total Nephron Albumin Filtration and Reabsorption in Diabetic Nephropathy. J Am Soc Nephrol 2016; 28:278-289. [PMID: 27382987 DOI: 10.1681/asn.2015101168] [Citation(s) in RCA: 53] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2015] [Accepted: 05/28/2016] [Indexed: 12/20/2022] Open
Abstract
The amount of albumin filtered through the glomeruli and reabsorbed at the proximal tubules in normal and in diabetic kidneys is debated. The megalin/cubilin complex mediates protein reabsorption, but genetic knockout of megalin is perinatally lethal. To overcome current technical problems, we generated a drug-inducible megalin-knockout mouse line, megalin(lox/lox);Ndrg1-CreERT2 (iMegKO), in which megalin expression can be shut off at any time by administration of tamoxifen (Tam). Tam administration in adult iMegKO mice decreased the expression of renal megalin protein by 92% compared with that in wild-type C57BL/6J mice and almost completely abrogated renal reabsorption of intravenously injected retinol-binding protein. Furthermore, urinary albumin excretion increased to 175 μg/d (0.46 mg albumin/mg creatinine) in Tam-treated iMegKO mice, suggesting that this was the amount of total nephron albumin filtration. By comparing Tam-treated, streptozotocin-induced diabetic iMegKO mice with Tam-treated nondiabetic iMegKO mice, we estimated that the development of diabetes led to a 1.9-fold increase in total nephron albumin filtration, a 1.8-fold increase in reabsorption, and a significant reduction in reabsorption efficiency (86% efficiency versus 96% efficiency in nondiabetic mice). Insulin treatment normalized these abnormalities. Akita;iMegKO mice, another model of type 1 diabetes, showed equivalent results. Finally, nondiabetic iMegKO mice had a glomerular sieving coefficient of albumin of 1.7×10-5, which approximately doubled in diabetic iMegKO mice. This study reveals actual values and changes of albumin filtration and reabsorption in early diabetic nephropathy in mice, bringing new insights to our understanding of renal albumin dynamics associated with the hyperfiltration status of diabetic nephropathy.
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Affiliation(s)
| | | | - Masato Kasahara
- Department of Clinical and Translational Research, Institute for Clinical and Translational Science, Nara Medical University, Nara, Japan
| | | | | | - Takashige Kuwabara
- Department of Nephrology, Graduate School of Medical Sciences, Kumamoto University, Kumamoto, Japan
| | | | | | | | | | - Koichiro Kuwahara
- Department of Cardiovascular Medicine, Kyoto University Graduate School of Medicine, Kyoto, Japan
| | | | | | - Motoko Yanagita
- Department of Nephrology and.,TMK Project, Medical Innovation Center, Kyoto University Graduate School of Medicine, Kyoto, Japan
| | - Masashi Mukoyama
- Department of Nephrology, Graduate School of Medical Sciences, Kumamoto University, Kumamoto, Japan
| | - Kiyoshi Mori
- TMK Project, Medical Innovation Center, Kyoto University Graduate School of Medicine, Kyoto, Japan; .,Department of Molecular and Clinical Pharmacology, School of Pharmaceutical Sciences, University of Shizuoka, Shizuoka, Japan; and.,Department of Nephrology and Kidney Research, Shizuoka General Hospital, Shizuoka, Japan
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Garsen M, Benner M, Dijkman HB, van Kuppevelt TH, Li JP, Rabelink TJ, Vlodavsky I, Berden JHM, Rops ALWMM, Elkin M, van der Vlag J. Heparanase Is Essential for the Development of Acute Experimental Glomerulonephritis. THE AMERICAN JOURNAL OF PATHOLOGY 2016; 186:805-15. [PMID: 26873445 DOI: 10.1016/j.ajpath.2015.12.008] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/17/2015] [Revised: 11/26/2015] [Accepted: 12/08/2015] [Indexed: 01/20/2023]
Abstract
Heparanase, a heparan sulfate (HS)--specific endoglucuronidase, mediates the onset of proteinuria and renal damage during experimental diabetic nephropathy. Glomerular heparanase expression is increased in most proteinuric diseases. Herein, we evaluated the role of heparanase in two models of experimental glomerulonephritis, being anti-glomerular basement membrane and lipopolysaccharide-induced glomerulonephritis, in wild-type and heparanase-deficient mice. Induction of experimental glomerulonephritis led to an increased heparanase expression in wild-type mice, which was associated with a decreased glomerular expression of a highly sulfated HS domain, and albuminuria. Albuminuria was reduced in the heparanase-deficient mice in both models of experimental glomerulonephritis, which was accompanied by a better renal function and less renal damage. Notably, glomerular HS expression was preserved in the heparanase-deficient mice. Glomerular leukocyte and macrophage influx was reduced in the heparanase-deficient mice, which was accompanied by a reduced expression of both types 1 and 2 helper T-cell cytokines. In vitro, tumor necrosis factor-α and lipopolysaccharide directly induced heparanase expression and increased transendothelial albumin passage. Our study shows that heparanase contributes to proteinuria and renal damage in experimental glomerulonephritis by decreasing glomerular HS expression, enhancing renal leukocyte and macrophage influx, and affecting the local cytokine milieu.
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Affiliation(s)
- Marjolein Garsen
- Department of Nephrology, Radboud University Medical Center, Nijmegen, the Netherlands
| | - Marilen Benner
- Department of Nephrology, Radboud University Medical Center, Nijmegen, the Netherlands
| | - Henry B Dijkman
- Department of Pathology, Radboud University Medical Center, Nijmegen, the Netherlands
| | - Toin H van Kuppevelt
- Department of Biochemistry, Radboud University Medical Center, Nijmegen, the Netherlands
| | - Jin-Ping Li
- Department of Medical Biochemistry and Microbiology, Uppsala University, Uppsala, Sweden
| | - Ton J Rabelink
- Department of Nephrology, Leiden University Medical Center, Leiden, the Netherlands
| | - Israel Vlodavsky
- Cancer and Vascular Biology Research Center, Bruce Rappaport Faculty of Medicine, Technion, Haifa, Israel
| | - Jo H M Berden
- Department of Nephrology, Radboud University Medical Center, Nijmegen, the Netherlands
| | | | - Michael Elkin
- Sharett Institute, Hadassah-Hebrew University Medical Center, Jerusalem, Israel
| | - Johan van der Vlag
- Department of Nephrology, Radboud University Medical Center, Nijmegen, the Netherlands.
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Takahashi A, Fukusumi Y, Yamazaki M, Kayaba M, Kitazawa Y, Tomita M, Kawachi H. Angiotensin II type 1 receptor blockade ameliorates proteinuria in puromycin aminonucleoside nephropathy by inhibiting the reduction of NEPH1 and nephrin. J Nephrol 2014; 27:627-34. [PMID: 25298195 DOI: 10.1007/s40620-014-0147-z] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2014] [Accepted: 09/29/2014] [Indexed: 01/13/2023]
Abstract
BACKGROUND The precise pathogenic mechanism and role of angiotensin II (Ang II) action in the development of proteinuria in minimal change nephrotic syndrome (MCNS) is uncertain. METHODS The glomerular expressions of the slit diaphragm (SD) molecules nephrin, podocin and NEPH1 in rat puromycin aminonucleoside (PAN) nephropathy, a mimic of MCNS, were analyzed. The effects of Ang II receptor blockade (ARB) (irbesartan 15 mg/kg body weight/day) on proteinuria and on the expression of the SD molecules were analyzed. RESULTS mRNA expressions of nephrin, podocin and NEPH1 were decreased to an undetectable level at 1 h. The staining of these SD molecules shifted to a discontinuous pattern, and their intensity was reduced. NEPH1 staining was reduced to an undetectable level on day 10. ARB treatment ameliorated the peak value of proteinuria (237.6 ± 97.0 vs. 359.0 ± 63.3 mg/day, p < 0.05), and prevented the decrease in the mRNA expression of the SD molecules (nephrin 66.96 %, podocin 60.40 %, NEPH1 77.87 % of normal level). The immunofluorescence staining of NEPH1 was restored by ARB. ARB treatment enhanced the expression of NEPH1 of normal rats. CONCLUSIONS Dysfunction of the SD molecules including NEPH1 is a crucial initiation event of PAN nephropathy. ARB treatment ameliorates proteinuria in PAN nephropathy by inhibiting the reduction of NEPH1 and nephrin. Ang II action regulates the expression of NEPH1 and nephrin in not only the pathological but also physiological state.
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MESH Headings
- Angiotensin II Type 1 Receptor Blockers/pharmacology
- Animals
- Biphenyl Compounds/pharmacology
- Disease Models, Animal
- Disease Progression
- Female
- Gene Expression Regulation
- Intracellular Signaling Peptides and Proteins/metabolism
- Irbesartan
- Kidney Glomerulus/drug effects
- Kidney Glomerulus/metabolism
- Membrane Proteins/genetics
- Membrane Proteins/metabolism
- Nephrosis, Lipoid/chemically induced
- Nephrosis, Lipoid/drug therapy
- Nephrosis, Lipoid/genetics
- Nephrosis, Lipoid/metabolism
- Proteinuria/chemically induced
- Proteinuria/genetics
- Proteinuria/metabolism
- Proteinuria/prevention & control
- Puromycin Aminonucleoside
- Rats, Wistar
- Receptor, Angiotensin, Type 1/drug effects
- Receptor, Angiotensin, Type 1/metabolism
- Tetrazoles/pharmacology
- Time Factors
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Affiliation(s)
- Aya Takahashi
- Department of Cell Biology, Institute of Nephrology, Niigata University Graduate School of Medical and Dental Sciences, 1-757 Asahimachi-dori, Chuo-ku, Niigata, Niigata, 951-8510, Japan
| | - Yoshiyasu Fukusumi
- Department of Cell Biology, Institute of Nephrology, Niigata University Graduate School of Medical and Dental Sciences, 1-757 Asahimachi-dori, Chuo-ku, Niigata, Niigata, 951-8510, Japan
| | - Mihoko Yamazaki
- Department of Cell Biology, Institute of Nephrology, Niigata University Graduate School of Medical and Dental Sciences, 1-757 Asahimachi-dori, Chuo-ku, Niigata, Niigata, 951-8510, Japan
| | - Mutsumi Kayaba
- Department of Cell Biology, Institute of Nephrology, Niigata University Graduate School of Medical and Dental Sciences, 1-757 Asahimachi-dori, Chuo-ku, Niigata, Niigata, 951-8510, Japan
| | - Yukina Kitazawa
- Department of Cell Biology, Institute of Nephrology, Niigata University Graduate School of Medical and Dental Sciences, 1-757 Asahimachi-dori, Chuo-ku, Niigata, Niigata, 951-8510, Japan
| | - Masayuki Tomita
- Department of Cell Biology, Institute of Nephrology, Niigata University Graduate School of Medical and Dental Sciences, 1-757 Asahimachi-dori, Chuo-ku, Niigata, Niigata, 951-8510, Japan
| | - Hiroshi Kawachi
- Department of Cell Biology, Institute of Nephrology, Niigata University Graduate School of Medical and Dental Sciences, 1-757 Asahimachi-dori, Chuo-ku, Niigata, Niigata, 951-8510, Japan.
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Renal biopsy: use of biomarkers as a tool for the diagnosis of focal segmental glomerulosclerosis. DISEASE MARKERS 2014; 2014:192836. [PMID: 24719498 PMCID: PMC3955602 DOI: 10.1155/2014/192836] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 11/26/2013] [Revised: 01/15/2014] [Accepted: 01/15/2014] [Indexed: 12/12/2022]
Abstract
Focal segmental glomerulosclerosis (FSGS) is a glomerulopathy associated with nephrotic syndrome and podocyte injury. FSGS occurs both in children and adults and it is considered the main idiopathic nephrotic syndrome nowadays. It is extremely difficult to establish a morphological diagnosis, since some biopsies lack a considerable quantifiable number of sclerotic glomeruli, given their focal aspect and the fact that FSGS occurs in less than half of the glomeruli. Therefore, many biological molecules have been evaluated as potential markers that would enhance the diagnosis of FSGS. Some of these molecules and receptors are associated with the pathogenesis of FSGS and have potential use in diagnosis.
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Kim J, Patnaik N, Chorny N, Frank R, Infante L, Sethna C. Second-line immunosuppressive treatment of childhood nephrotic syndrome: a single-center experience. NEPHRON EXTRA 2014; 4:8-17. [PMID: 24575119 PMCID: PMC3934602 DOI: 10.1159/000357355] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
Abstract
Objective Most cases of idiopathic nephrotic syndrome in childhood are responsive to corticosteroids. However, there is a small group of children that demonstrate steroid resistance (steroid-resistant nephrotic syndrome; SRNS), steroid dependence, or that frequently relapse (frequent-relapse steroid-sensitive nephrotic syndrome; FR-SSNS) which are more clinically difficult to treat. Therefore, second-line immunosuppressants, such as alkylating agents, calcineurin inhibitors, antimetabolites and, more recently, rituximab, have been used with varying success. The objective was to evaluate the response rates of various second-line therapies in the treatment of childhood nephrotic syndrome. Study Design A retrospective chart review of pediatric subjects with idiopathic nephrotic syndrome was conducted at a single tertiary care center (2007-2012). Drug responses were classified as complete response, partial response, and no response. Results Of the 188 charts reviewed, 121 children were classified as SSNS and 67 children as SRNS; 58% were classified as FR-SSNS. Sixty-five subjects were diagnosed with focal segmental glomerulosclerosis via biopsy. Follow-up ranged from 6 months to 21 years. The combined rate of complete and partial response for mycophenolate mofetil (MMF) was 65% (33/51) in SSNS and 67% (6/9) in SRNS. For tacrolimus, the response rate was 96% (22/23) for SSNS and 77% (17/22) for SRNS. Eighty-three percent (5/6) of SSNS subjects treated with rituximab went into complete remission; 60% relapsed after B-cell repletion. Eight refractory subjects were treated with combined MMF/tacrolimus/corticosteroid therapy with a 75% response rate. Conclusion Our experience demonstrates that older medications can be replaced with newer ones such as MMF, tacrolimus, and rituximab with good outcomes and better side effect profiles. The treatment of refractory cases with combination therapy is promising.
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Affiliation(s)
- J Kim
- Division of Pediatric Nephrology, Department of Pediatrics, Cohen Children's Medical Center of New York, North Shore-LIJ Health System, New Hyde Park, N.Y., USA
| | - N Patnaik
- Division of Pediatric Nephrology, Department of Pediatrics, Cohen Children's Medical Center of New York, North Shore-LIJ Health System, New Hyde Park, N.Y., USA
| | - N Chorny
- Division of Pediatric Nephrology, Department of Pediatrics, Cohen Children's Medical Center of New York, North Shore-LIJ Health System, New Hyde Park, N.Y., USA
| | - R Frank
- Division of Pediatric Nephrology, Department of Pediatrics, Cohen Children's Medical Center of New York, North Shore-LIJ Health System, New Hyde Park, N.Y., USA
| | - L Infante
- Division of Pediatric Nephrology, Department of Pediatrics, Cohen Children's Medical Center of New York, North Shore-LIJ Health System, New Hyde Park, N.Y., USA
| | - C Sethna
- Division of Pediatric Nephrology, Department of Pediatrics, Cohen Children's Medical Center of New York, North Shore-LIJ Health System, New Hyde Park, N.Y., USA
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36
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Garsen M, Rops AL, Rabelink TJ, Berden JH, van der Vlag J. The role of heparanase and the endothelial glycocalyx in the development of proteinuria. Nephrol Dial Transplant 2013; 29:49-55. [DOI: 10.1093/ndt/gft410] [Citation(s) in RCA: 73] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Yuan H, Liu N, Sun GD, Jia Y, Luo P, Miao LN. Effect of prolonged tacrolimus treatment in idiopathic membranous nephropathy with nephrotic syndrome. Pharmacology 2013; 91:259-66. [PMID: 23652322 DOI: 10.1159/000348570] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2012] [Accepted: 01/23/2013] [Indexed: 11/19/2022]
Abstract
OBJECTIVE Tacrolimus has been used for idiopathic membranous nephropathy (IMN) therapy, but most patients who achieved remission showed a high relapse rate when tacrolimus was withdrawn after 6-12 months of therapy. We proposed that a prolonged therapeutic course should help reduce the relapse rate. METHODS A total of 42 patients with nephrotic syndrome caused by IMN were randomly divided into short-term (n = 20) and long-term (n = 22) groups. All patients received initial treatment with tacrolimus and prednisone for 6 months, and afterward only the long-term patient group was tapered with low-dose tacrolimus until 24 months. RESULTS Over 85% of the patients achieved proteinuria reduction, serum albumin improvement and serum lipid recovery; the probability of remission in both groups was over 80% at 6 months. The remission rate was steady at over 80% after 12 and 24 months in the long-term group, but only 50 and 45%, respectively, in the short-term group. Nine patients (45%) relapsed in the short-term group after tacrolimus withdrawal, while not a single patient suffered recurrence in the long-term group. The concentration of tacrolimus remained similar between the two groups at 5-8 ng/ml during the initial 6 months, and was significantly decreased at 12 months compared to 6 months (p < 0.05), along with reduction of oral administration in the long-term group. CONCLUSION Combined therapy of tacrolimus with prednisone can relieve IMN significantly; prolonged tacrolimus treatment at a low blood concentration can alleviate the illness persistently, with a low recurrence rate and gratifying safety.
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Affiliation(s)
- Hang Yuan
- Department of Nephrology, Second Hospital of Jilin University, Changchun, China
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Komorowsky CV, Brosius FC, Pennathur S, Kretzler M. Perspectives on systems biology applications in diabetic kidney disease. J Cardiovasc Transl Res 2012; 5:491-508. [PMID: 22733404 PMCID: PMC3422674 DOI: 10.1007/s12265-012-9382-7] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/13/2012] [Accepted: 05/22/2012] [Indexed: 12/18/2022]
Abstract
Diabetic kidney disease (DKD) is a microvascular complication of type 1 and 2 diabetes with a devastating impact on individuals with the disease, their families, and society as a whole. DKD is the single most frequent cause of incident chronic kidney disease cases and accounts for over 40% of the population with end-stage renal disease. Contributing factors for the high prevalence are the increase in obesity and subsequent diabetes combined with an improved long-term survival with diabetes. Environment and genetic variations contribute to DKD susceptibility and progressive loss of kidney function. How the molecular mechanisms of genetic and environmental exposures interact during DKD initiation and progression is the focus of ongoing research efforts. The development of standardized, unbiased high-throughput profiling technologies of human DKD samples opens new avenues in capturing the multiple layers of DKD pathobiology. These techniques routinely interrogate analytes on a genome-wide scale generating comprehensive DKD-associated fingerprints. Linking the molecular fingerprints to deep clinical phenotypes may ultimately elucidate the intricate molecular interplay in a disease stage and subtype-specific manner. This insight will form the basis for accurate prognosis and facilitate targeted therapeutic interventions. In this review, we present ongoing efforts from large-scale data integration translating "-omics" research efforts into improved and individualized health care in DKD.
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Affiliation(s)
- Claudiu V. Komorowsky
- Department of Internal Medicine, Division of Nephrology, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Frank C. Brosius
- Department of Internal Medicine, Division of Nephrology, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Subramaniam Pennathur
- Department of Internal Medicine, Division of Nephrology, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Matthias Kretzler
- Department of Internal Medicine, Division of Nephrology, University of Michigan Medical School, Ann Arbor, MI, USA
- Department of Computational Medicine and Bioinformatics, University of Michigan Medical School, Ann Arbor, MI, USA
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Gulati A, Sinha A, Gupta A, Kanitkar M, Sreenivas V, Sharma J, Mantan M, Agarwal I, Dinda AK, Hari P, Bagga A. Treatment with tacrolimus and prednisolone is preferable to intravenous cyclophosphamide as the initial therapy for children with steroid-resistant nephrotic syndrome. Kidney Int 2012; 82:1130-5. [PMID: 22763815 DOI: 10.1038/ki.2012.238] [Citation(s) in RCA: 69] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
There are limited data on the relative efficacy and safety of calcineurin inhibitors and alkylating agents for idiopathic steroid-resistant nephrotic syndrome in children. To clarify this, we compared tacrolimus and intravenous cyclophosphamide therapy in a multicenter, randomized, controlled trial of 131 consecutive pediatric patients with minimal change disease, focal segmental glomerulosclerosis, or mesangioproliferative glomerulonephritis, stratified for initial or late steroid resistance. Patients were randomized to receive tacrolimus for 12 months or 6-monthly infusions of intravenous cyclophosphamide with both arms receiving equal amounts of alternate-day prednisolone. The primary outcome of complete or partial remission at 6 months, based on spot urine protein to creatinine ratios, was significantly higher in children receiving tacrolimus compared to cyclophosphamide (hazard ratio 2.64). Complete remission was significantly higher with tacrolimus (52.4%) than with cyclophosphamide (14.8%). The secondary outcome of sustained remission or steroid-sensitive relapse of nephrotic syndrome at 12 months was significantly higher with tacrolimus than cyclophosphamide. Treatment withdrawal was higher with cyclophosphamide, chiefly due to systemic infections. Compared to cyclophosphamide, 3 patients required treatment with tacrolimus to achieve 1 additional remission. Thus, tacrolimus and prednisolone are effective, safe, and preferable to cyclophosphamide as the initial therapy for patients with steroid-resistant nephrotic syndrome.
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Affiliation(s)
- Ashima Gulati
- Department of Pediatrics, All India Institute of Medical Sciences, New Delhi, India
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40
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Molina L, Salvetat N, Ameur RB, Peres S, Sommerer N, Jarraya F, Ayadi H, Molina F, Granier C. Analysis of the variability of human normal urine by 2D-GE reveals a “public” and a “private” proteome. J Proteomics 2011; 75:70-80. [DOI: 10.1016/j.jprot.2011.06.031] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2011] [Revised: 06/22/2011] [Accepted: 06/25/2011] [Indexed: 01/30/2023]
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Lisowska-Myjak B, Krych A, Kołodziejczyk A, Pachecka J, Gaciong Z. Urinary proteins, N-acetyl-β-D-glucosaminidase activity and estimated glomerular filtration rate in hypertensive patients with normoalbuminuria and microalbuminuria. Nephrology (Carlton) 2011; 16:403-9. [PMID: 21265931 DOI: 10.1111/j.1440-1797.2011.01444.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
BACKGROUND The aim of the study was to assess novel candidate markers measured in the urine of normoalbuminuric and microalbuminuric patients (the urinary albumin-to-creatinine ratio < 30 mg/mmol) with essential hypertension to be used for early detection and assessment of progressive deterioration in renal function. METHODS Albumin, α-1-antitrypsin, orosomucoid, transferrin, retinol-binding protein and α-1-microglobulin concentrations and the NAG (N-acetyl-β-D-glucosaminidase) activity in the urine were evaluated in 102 hypertensive subjects with urinary albumin-to-creatinine ratio (uACR) < 30 mg/mmol. The estimated glomerular filtration rate (e-GFR) was calculated using the Modification of Diet in Renal Disease Study equation. RESULTS The decreasing e-GFR values in normo- and microalbuminuric patients with essential hypertension were accompanied by significant increases (P < 0.05) in the NAG activity and uACR value in the urine. The e-GFR significantly (P < 0.05) correlated with the NAG activity in the urine, but no association was observed with the urinary concentrations of any of the individual proteins (P > 0.05). CONCLUSIONS In normoalbuminuric and microalbuminuric patients with essential hypertension renal impairment measured by e-GFR is related to the increased urinary NAG activity and uACR rather than elevated concentrations of individual proteins. Urinary NAG activity and uACR value seem independently promising candidate markers for use in assessing progression of early renal impairment in patients with hypertension.
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Affiliation(s)
- Barbara Lisowska-Myjak
- Department of Biochemistry and Clinical Chemistry, Medical University of Warsaw, Warsaw, Poland. basia.myjak@ interia.pl
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Huang ZS, Chen YM, Wu KD, Chen MF. Higher peripheral neutrophil and monocyte counts are independent indicators of the presence and severity of proteinuria in apparently normal adults. Intern Med J 2011; 40:30-6. [PMID: 20561363 DOI: 10.1111/j.1445-5994.2008.01881.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
BACKGROUND Proteinuria reflects disrupted renal function in which enhanced immuno-inflammation activity plays a key role. So far, information concerning the relations between proteinuria and peripheral different leucocyte counts is limited. We thereby conducted this study aiming to obtain comprehensive information of the issue. METHODS Study subjects were participants of a health check programme from 2000 to 2002. Additional two enrolment criteria were (i) leucocyte analysis was checked with a same blood cell counter and (ii) urinalysis showed no pyuria or haematuria. Data of subjects were retrospectively collected and analysed by using sas program. RESULTS Higher neutrophil and monocyte counts, but not lymphocyte count, were significantly associated with both the presence and the severity of proteinuria (all P < 0.0001, n= 12 225). Such associations maintained significant after adjustments of age, sex, body mass index, mean blood pressure and blood levels of glycosylated hemoglobin (HbA1c), total cholesterol, triglycerides and creatinine (all P< or = 0.001, n= 12 225). There was a sharp increase in the incidence of proteinuria in association with a neutrophil count > or =4.50 x 10(9)/L (P< or = 0.0001). CONCLUSION Our study showed that in apparently normal adults the presence and the severity of proteinuria could be reflected by the peripheral neutrophil and monocyte counts, but not the lymphocyte count. These findings, together with the documented inflammatory basis of proteinuria and the diverse pathophysiological roles of differential leucocytes, suggest that peripheral differential leucocyte counting may be useful in predicting the course of an existing proteinuria. Perspective longitudinal follow-up studies are needed to test this presumption.
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Affiliation(s)
- Z-S Huang
- Department of Internal Medicine, National Taiwan University Hospital, College of Medicine, National Taiwan University, Taipei, Taiwan.
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Ritz E, Schmieder RE, Pollock CA. Renal protection in diabetes: lessons from ONTARGET. Cardiovasc Diabetol 2010; 9:60. [PMID: 20920303 PMCID: PMC2959007 DOI: 10.1186/1475-2840-9-60] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/23/2010] [Accepted: 10/01/2010] [Indexed: 01/13/2023] Open
Abstract
Hypertension is an important independent risk factor for renal disease. If hypertension and chronic renal disease co-exist, as is common in patients with diabetes mellitus, the risk of cardiovascular disease is heightened. The importance of rigorous blood pressure control is recognized in current guidelines, with a recommended target of office blood pressure of < 130/80 mmHg; although ambulatory blood pressure may be more appropriate in order to identify the 24-hour hypertensive burden. Even lower blood pressure may further reduce the progression of chronic kidney disease, but the incidence of cardiovascular events may increase. Albuminuria not only indicates renal damage, but is also a powerful predictor of cardiovascular morbidity and mortality at least in patients with high cardiovascular risk and potentially pre-existing vascular damage. Management of the multiple factors for renal and cardiovascular disease is mandatory in the diabetic patient. The renin-angiotensin system (RAS) plays a pivotal role in the progression of renal disease, as well as in hypertension and target-organ damage. The use of agents that target the RAS confer renoprotection in addition to antihypertensive activity. There is extensive evidence of the renoprotective effect of angiotensin II receptor blockers (ARBs), and specifically telmisartan. In addition to providing 24-hour blood pressure control, clinical studies in patients with diabetes show that telmisartan improves renal endothelial function, prevents progression from microalbuminuria to macroalbuminuria, slows the decline in glomerular filtration rate and reduces proteinuria in overt nephropathy. These effects cannot be solely attributed to blood pressure control. In contrast to other members of the ARB class, the renoprotective effect of telmisartan is not confined to the management of diabetic nephropathy; slowing the progression of albuminuria has been demonstrated in the ONgoing Telmisartan Alone and in combination with Ramipril Global Endpoint Trial (ONTARGET), which included diabetic and non-diabetic patients at high risk of cardiovascular events.
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Affiliation(s)
- Eberhard Ritz
- Universitat Erlangen, Medizinische Klinik IV, Erlangen, Germany
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Stitt-Cavanagh EM, Faour WH, Takami K, Carter A, Vanderhyden B, Guan Y, Schneider A, Breyer MD, Kennedy CRJ. A maladaptive role for EP4 receptors in podocytes. J Am Soc Nephrol 2010; 21:1678-90. [PMID: 20671216 DOI: 10.1681/asn.2009121234] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
Abstract
Inhibition of p38 mitogen-activated protein kinase and cyclooxygenase-2 reduces albuminuria in models of chronic kidney disease marked by podocyte injury. Previously, we identified a feedback loop in podocytes whereby an in vitro surrogate for glomerular capillary pressure (i.e., mechanical stretch) along with prostaglandin E(2) stimulation of its EP4 receptor induced cyclooxygenase-2 in a p38-dependent manner. Here we asked whether stimulation of EP4 receptors would exacerbate glomerulopathies associated with enhanced glomerular capillary pressure. We generated mice with either podocyte-specific overexpression or depletion of the EP4 receptor (EP4(pod+) and EP4(pod-/-), respectively). Glomerular prostaglandin E(2)-stimulated cAMP levels were eightfold greater for EP4(pod+) mice compared with nontransgenic (non-TG) mice. In contrast, EP4 mRNA levels were >50% lower, and prostaglandin E(2)-induced cAMP synthesis was absent in podocytes isolated from EP4(pod-/-) mice. Non-TG and EP4(pod+) mice underwent 5/6 nephrectomy and exhibited similar increases in systolic BP (+25 mmHg) by 4 weeks compared with sham-operated controls. Two weeks after nephrectomy, the albumin-creatinine ratio of EP4(pod+) mice (3438 μg/mg) was significantly higher than that of non-TG mice (773 μg/mg; P < 0.0001). Consistent with more severe renal injury, the survival rate for nephrectomized EP4(pod+) mice was significantly lower than that for non-TG mice (14 versus 67%). In contrast, 6 weeks after nephrectomy, the albumin-creatinine ratio of EP4(pod-/-) mice (753 μg/mg) was significantly lower than that of non-TG mice (2516 μg/mg; P < 0.05). These findings suggest that prostaglandin E(2), acting via EP4 receptors contributes to podocyte injury and compromises the glomerular filtration barrier.
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Affiliation(s)
- Erin M Stitt-Cavanagh
- Kidney Research Centre, Division of Nephrology, Department of Medicine, Ottawa Hospital, Ottawa Hospital Research Institute, Ottawa, Ontario, Canada
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45
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Roberti I, Vyas S. Long-term outcome of children with steroid-resistant nephrotic syndrome treated with tacrolimus. Pediatr Nephrol 2010; 25:1117-24. [PMID: 20217433 DOI: 10.1007/s00467-010-1471-8] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/02/2009] [Revised: 11/23/2009] [Accepted: 01/12/2010] [Indexed: 11/26/2022]
Abstract
We report the outcome of our single-center, long-term follow-up study of tacrolimus therapy in children with steroid-resistant nephrotic syndrome (SRNS). All cases of nephrotic syndrome (NS) with kidney biopsies treated at our center between January 2000 and July 2008 were reviewed. Children with systemic lupus erythematosus and steroid-dependent NS were excluded. Nineteen children with SRNS received tacrolimus. Histopathological analysis of the biopsy revealed the underlying conditions of these 19 patients to be focal segmental glomerulosclerosis (ten patients), C1q nephropathy (four), membranous nephropathy (two), minimal change disease (one), membranoproliferative glomerulonephritis (one), and immunoglobulin A nephropathy (one). The mean follow-up was 55 months, and the median age of the patient cohort was 10 years. We observed complete remission in 11 (58%) patients, partial remission in six (32%), and failure to respond in two (9%). The median time to response was 8 weeks. Side effects were mild and transient (one case of acute kidney injury and three cases of hyperglycemia). The initial rate for combined partial and complete remission of the NS in children with SRNS was 81%, which was sustained in 58% of the patients on follow-up. Among children with FSGS, the sustained remission rate was 50%, while 40% progressed to end-stage renal disease (ESRD) (mean time 52 months). Based on the results of this study, we conclude that tacrolimus is an effective and well-tolerated therapeutic option for the treatment of SRNS in children. However, the occurrence of relapses of the NS with progression to ESRD during the long-term follow-up indicates the need for careful monitoring of such patients.
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Affiliation(s)
- Isabel Roberti
- Pediatric Nephrology and Transplantation, Saint Barnabas Medical Center, 94 Old Short Hills Road, East Wing suite 304, Livingston, NJ, 07039, USA.
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Candiano G, Santucci L, Petretto A, Bruschi M, Dimuccio V, Urbani A, Bagnasco S, Ghiggeri GM. 2D-electrophoresis and the urine proteome map: Where do we stand? J Proteomics 2010; 73:829-44. [DOI: 10.1016/j.jprot.2009.12.003] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2009] [Revised: 11/30/2009] [Accepted: 12/02/2009] [Indexed: 12/19/2022]
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Thongboonkerd V, Mungdee S, Chiangjong W. Should urine pH be adjusted prior to gel-based proteome analysis? J Proteome Res 2009; 8:3206-11. [PMID: 19351137 DOI: 10.1021/pr900127x] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
The urine has become one of the most widely used clinical samples for biomarker discovery. The pH of human urine may vary largely from 4.5 to 8.0. Previously, it was questionable whether the urine pH would affect proteome analysis and whether the urine pH needed to be adjusted prior to proteome analysis remained unclear. We therefore performed a systematic analysis of the effect of urine pH on proteome profile. Midstream second morning and random afternoon urine samples were collected from 5 males and 5 females who were healthy and had no recent medication. After removal of cells and debris by low-speed centrifugation, pH levels of individual samples were measured and urinary proteins were isolated by 75% ethanol precipitation. Equally loaded 100 microg of proteins from individual samples were resolved in 2-DE (linear pH 3-10) and visualized with SYPRO Ruby fluorescence stain. There was no significant correlation between difference in the morning versus afternoon urine pH (DeltapH) and %match of protein spots derived from morning versus afternoon urine samples in individual samples (Pearson's r = 0.074; p = 0.839). In parallel, all individual samples with equal volume were pooled. The pH of the pooled urine was adjusted to 4-10 and urinary proteome profiles were analyzed as for individual samples. ANOVA with Tukey's posthoc multiple comparisons showed no significant differences in total number of detected spots and %match among various pH levels. Our data suggest that the urine pH has no significant effects on urinary proteome profile and thus needs no adjustment prior to gel-based proteome analysis.
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Affiliation(s)
- Visith Thongboonkerd
- Medical Proteomics Unit, Office for Research and Development, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand.
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Ahmed FE. Liquid chromatography–mass spectrometry: a tool for proteome analysis and biomarker discovery and validation. ACTA ACUST UNITED AC 2009; 3:429-44. [DOI: 10.1517/17530050902832855] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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Xia L, Zhou M, Kalhorn TF, Ho HTB, Wang J. Podocyte-specific expression of organic cation transporter PMAT: implication in puromycin aminonucleoside nephrotoxicity. Am J Physiol Renal Physiol 2009; 296:F1307-13. [PMID: 19357181 DOI: 10.1152/ajprenal.00046.2009] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
Plasma membrane monoamine transporter (PMAT) is a novel polyspecific organic cation transporter that transports organic cations and the purine nucleoside, adenosine. PMAT is expressed in the kidney, but the specific localization and function of this transporter in renal cells are unclear. In this study, we developed a polyclonal antibody toward a 14-amino acid sequence in the last intracellular loop of PMAT and determined the precise cellular localization of PMAT in human and rat kidneys. Surprisingly, we found that the PMAT protein was predominantly expressed in the glomerulus with minimal expression in tubular cells. Within the glomerulus, dual-color immunofluorescence labeling showed that the PMAT protein was specifically localized to the visceral glomerular epithelial cells, i.e., podocytes. There was no significant PMAT immunoreactivity in mesangial or glomerular endothelial cells. We further showed that puromycin aminonucleoside (PAN), a classic podocyte toxin that induces massive proteinuria and severe glomerulopathy, is transported by PMAT. Expression of PMAT in Madin-Darby canine kidney cells significantly increased cell sensitivity to PAN. Decynium 22, a potent PMAT inhibitor, abolished PAN toxicity in PMAT-expressing cells. Together, our data suggest that PMAT is specifically expressed in podocytes and may play an important role in PAN-induced kidney injury.
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Affiliation(s)
- Li Xia
- Department of Pharmaceutics, H272J Health Sciences Bldg., Univ. of Washington, Seattle, WA 98195-7610, USA
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