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Fukuda A, Sato Y, Shibata H, Fujimoto S, Wiggins RC. Urinary podocyte markers of disease activity, therapeutic efficacy, and long-term outcomes in acute and chronic kidney diseases. Clin Exp Nephrol 2024; 28:496-504. [PMID: 38402504 PMCID: PMC11116200 DOI: 10.1007/s10157-024-02465-y] [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: 12/18/2023] [Accepted: 01/14/2024] [Indexed: 02/26/2024]
Abstract
A critical degree of podocyte depletion causes glomerulosclerosis, and persistent podocyte loss in glomerular diseases drives the progression to end-stage kidney disease. The extent of podocyte injury at a point in time can be histologically assessed by measuring podocyte number, size, and density ("Biopsy podometrics"). However, repeated invasive renal biopsies are associated with increased risk and cost. A noninvasive method for assessing podocyte injury and depletion is required. Albuminuria and proteinuria do not always correlate with disease activity. Podocytes are located on the urinary space side of the glomerular basement membrane, and as they undergo stress or detach, their products can be identified in urine. This raises the possibility that urinary podocyte products can serve as clinically useful markers for monitoring glomerular disease activity and progression ("Urinary podometrics"). We previously reported that urinary sediment podocyte mRNA reflects disease activity in both animal models and human glomerular diseases. This includes diabetes and hypertension which together account for 60% of new-onset dialysis induction patients. Improving approaches to preventing progression is an urgent priority for the renal community. Sufficient evidence now exists to indicate that monitoring urinary podocyte markers could serve as a useful adjunctive strategy for determining the level of current disease activity and response to therapy in progressive glomerular diseases.
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Affiliation(s)
- Akihiro Fukuda
- Department of Endocrinology, Metabolism, Rheumatology and Nephrology, Faculty of Medicine, Oita University, 1-1 Idaigaoka, Hasama-Machi, Yufu City, Oita, 879-5593, Japan.
| | - Yuji Sato
- Division of Nephrology, Department of Internal Medicine, National Health Insurance Takachiho Town Hospital, Takachiho, Miyazaki, Japan
| | - Hirotaka Shibata
- Department of Endocrinology, Metabolism, Rheumatology and Nephrology, Faculty of Medicine, Oita University, 1-1 Idaigaoka, Hasama-Machi, Yufu City, Oita, 879-5593, Japan
| | - Shouichi Fujimoto
- Department of Medical Environment Innovation, Faculty of Medicine, University of Miyazaki, Miyazaki, Japan
| | - Roger C Wiggins
- Division of Nephrology, Department of Internal Medicine, University of Michigan, Ann Arbor, MI, USA
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Okabe M, Koike K, Yamamoto I, Tsuboi N, Matsusaka T, Yokoo T. Early growth response 1 as a podocyte injury marker in human glomerular diseases. Clin Kidney J 2024; 17:sfad289. [PMID: 38186896 PMCID: PMC10768762 DOI: 10.1093/ckj/sfad289] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2023] [Indexed: 01/09/2024] Open
Abstract
Background In human glomerular diseases, visualizing podocyte injury is desirable since podocytes do not regenerate and podocyte injury leads to podocyte loss. Herein, we investigated the utility of immunostaining for early growth response 1 (EGR1), which is expressed in injured podocytes from the early stages of injury in animal experiments, as a podocyte injury marker in human glomerular diseases. Methods This study included 102 patients with biopsy-proven glomerular diseases between 2018 and 2021. The proportion of EGR1 expression in podocytes (%EGR1pod) was analyzed in relation to clinical and histopathological features, including glomerular and urinary podocyte-specific markers. Results %EGR1pod correlated significantly with the urinary protein:creatinine ratio, urinary nephrin and podocin mRNA levels, and glomerular podocin staining (rho = 0.361, 0.514, 0.487 and -0.417, respectively; adjusted P = .002, <.001, <.001 and <.001, respectively). Additionally, %EGR1pod correlated with cellular/fibrocellular crescents (rho = 0.479, adjusted P <.001). %EGR1pod was high in patients with glomerulonephritis, such as immunoglobulin A nephropathy (IgAN), lupus nephritis and antineutrophil cytoplasmic antibody-associated glomerulonephritis, and in those with podocytopathies, such as membranous nephropathy and primary focal segmental glomerulosclerosis, while %EGR1pod was low in patients with minimal change disease. In a subgroup analysis of IgAN, %EGR1pod was higher in Oxford C1 patients than in C0 patients. However, unexpectedly, patients with higher %EGR1pod were more prone to attain proteinuria remission, suggesting that EGR1 in the context of IgAN reflects reversible early injury. Conclusions Our findings indicate that EGR1 is a promising potential marker for identifying active early podocyte injury in human glomerular diseases.
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Affiliation(s)
- Masahiro Okabe
- Division of Nephrology and Hypertension, Department of Internal Medicine, Jikei University School of Medicine, Tokyo, Japan
| | - Kentaro Koike
- Division of Nephrology and Hypertension, Department of Internal Medicine, Jikei University School of Medicine, Tokyo, Japan
| | - Izumi Yamamoto
- Division of Nephrology and Hypertension, Department of Internal Medicine, Jikei University School of Medicine, Tokyo, Japan
| | - Nobuo Tsuboi
- Division of Nephrology and Hypertension, Department of Internal Medicine, Jikei University School of Medicine, Tokyo, Japan
| | - Taiji Matsusaka
- Departments of Basic Medicine, Tokai University School of Medicine, Isehara, Japan
| | - Takashi Yokoo
- Division of Nephrology and Hypertension, Department of Internal Medicine, Jikei University School of Medicine, Tokyo, Japan
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Viswanatha Setty B, Gutlur Nagarajaiah Setty R, Rangaswamaiah H, Veluri G. Podocalyxin in the onset of nephropathy among Indian type 2 diabetes mellitus patients. Bioinformation 2023; 19:1124-1128. [PMID: 38250530 PMCID: PMC10794751 DOI: 10.6026/973206300191124] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2023] [Revised: 12/31/2023] [Accepted: 12/31/2023] [Indexed: 01/23/2024] Open
Abstract
The diabetic nephropathy is one of the most prevalent microvascular complications with type 2 diabetes mellitus. The most accurate and widely used marker for diabetic nephropathy is microalbuminuria and it is also regarded as conventional method. However, it is not a sensitive or specific nephropathy biomarker. Therefore, it is of interest to evaluate the role of podocalyxin to predict early onset of nephropathy in patients with type 2 diabetes mellitus. This cross - sectional study is conducted on 150 subjects. Among these 150 T2DM patients (Group 2: T2DM with normoalbuminuria and Group 3: T2DM with microalbuminuria) and 50 were age, gender and BMI matched healthy controls (Group 1). The biochemical and experimental parameters was analyzed. T2DM patients have higher levels of urine podocalyxin. This level was significantly elevated in patients with T2DM with microalbuminuria than normoalbuminuria. Urinary podocalyxin levels and HbA1c were found to be positively correlated. Thus, urinary podocalyxin is useful as early predictable marker for nephropathy in patients with type 2 diabetes mellitus.
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Affiliation(s)
- Balaji Viswanatha Setty
- Department of General Medicine, Rajarajeshwari Medical College and Hospital, Bangalore, Karnataka, India
| | | | - Hareesh Rangaswamaiah
- Department of General Medicine, Akash Institute of Medical Sciences and Research Centre, Bangalore, Karnataka, India
| | - Ganesh Veluri
- Department of Biochemistry, ESIC Medical College and Hospital, Kalaburagi, Karnataka, India
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Terinte-Balcan G, Stefan G. A closer look: ultrastructural evaluation of high-risk progression IgA nephropathy. Ultrastruct Pathol 2023; 47:461-469. [PMID: 37700534 DOI: 10.1080/01913123.2023.2256836] [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: 07/25/2023] [Accepted: 09/05/2023] [Indexed: 09/14/2023]
Abstract
This retrospective, cross-sectional study sought to examine the ultrastructural characteristics of glomerular lesions using Transmission Electron Microscopy (TEM) in IgA nephropathy (IgAN) and their relationship with the high risk of progression phenotype defined by KDIGO guideline as proteinuria ≥1 g/24 hours despite 3 months of optimized supportive care. We analyzed 81 IgAN patients (median age 41 years, 67% male, eGFR 43.8 mL/min, proteinuria 1.04 g/day); 42 (52%) of them had high risk of progression. There were no differences in terms of age, sex, comorbidities, eGFR, and hematuria between the two groups. High-risk patients more often had segmental glomerulosclerosis (29% vs 8%, p 0.01) in optical microscopy, while in TEM had more frequent podocyte hypertrophy (62% vs 26%, p 0.001) and podocyte foot process detachment from the glomerular basement membrane (19% vs 8%, p 0.05), more often thicker (19% vs 5%, p 0.05) and duplicated (26% vs 10%, p 0.05) glomerular basement membrane, and the presence of subendothelial and subepithelial deposits (31% vs 13%, p 0.05). However, in multivariate binary logistic regression analysis, only podocyte hypertrophy (OR 3.14; 95%CI 1.12, 8.79) was an independent risk factor for high-risk progression in IgAN. These findings highlight the importance of podocytopathy in IgAN progression.
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Affiliation(s)
- George Terinte-Balcan
- Department of Nephrology, University of Medicine and Pharmacy "Carol Davila", Bucharest, Romania
- Ultrastructural Pathology Laboratory, "Victor Babes" National Institute of Pathology, Bucharest, Romania
| | - Gabriel Stefan
- Department of Nephrology, University of Medicine and Pharmacy "Carol Davila", Bucharest, Romania
- Department of Nephrology, "Dr. Carol Davila" Teaching Hospital of Nephrology, Bucharest, Romania
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Terinte-Balcan G, Stancu S, Zugravu A, Capusa C, Radu A, Mircescu G, Stefan G. Prognostic role of glomerular electron microscopy lesions in IgA nephropathy: "the devil is in the details". J Nephrol 2023; 36:2233-2243. [PMID: 37632668 DOI: 10.1007/s40620-023-01744-3] [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: 05/25/2023] [Accepted: 07/28/2023] [Indexed: 08/28/2023]
Abstract
INTRODUCTION Transmission electron microscopy enables examination of ultrastructural glomerular changes; while this tool has already been applied in IgA nephropathy (IgAN), limited information exists on the prognostic value in this disease. We aimed to systematically investigate ultrastructural lesions and assess their role in predicting the evolution of IgA nephropathy to end-stage kidney disease. METHODS A single-center retrospective study was performed on 107 consecutive IgAN patients (median age 42 years, 67% male, estimated glomerular filtration rate 46 mL/min, proteinuria 1.0 g/g) between 2010 and 2015, who were followed-up until end-stage kidney disease, death, or end of study (January 2021). A pathologist evaluated the Mesangial hypercellularity (M), Endocapillary hypercellularity (E), Segmental glomerulosclerosis (S), and Tubular atrophy/interstitial fibrosis-Crescents (C) (MEST-C) score and transmission electron microscopy lesions according to a comprehensive protocol that encompassed all glomerular structures. RESULTS Patients were followed up for a median of 7.1 years; 32 (43%) reached end-stage kidney disease. Patients who reached kidney failure had higher comorbidity score, more frequent arterial hypertension, lower estimated glomerular filtration rate, and higher MEST-C score. In terms of transmission electron microscopy lesions, patients who progressed to end-stage kidney disease had more frequent podocyte activation, effacement, and presence of microvilli; more frequent signs of endothelial cell activation and fenestration; higher mesangial cell proliferation. In the univariate Cox proportional hazard regression, higher MEST-C score and lesions detected by transmission electron microscopy in podocytes, endothelial cells, and mesangial cell proliferation were associated with shorter kidney survival time. In the multivariate Cox proportional hazard regression, only higher MEST-C score, presence of podocytes with microvilli, and mesangial cell proliferation were associated with end-stage kidney disease. CONCLUSION This study shows that, besides the MEST-C score, the presence of podocytes with microvilli and mesangial cell proliferation are associated with poor kidney survival in IgAN patients, highlighting the prognostic value of lesions detected by transmission electron microscopy.
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Affiliation(s)
- George Terinte-Balcan
- University of Medicine and Pharmacy "Carol Davila", Bucharest, Romania
- Ultrastructural Pathology Laboratory, "Victor Babes" National Institute of Pathology, Bucharest, Romania
| | - Simona Stancu
- University of Medicine and Pharmacy "Carol Davila", Bucharest, Romania
- "Dr. Carol Davila" Teaching Hospital of Nephrology, Bucharest, Romania
| | - Adrian Zugravu
- University of Medicine and Pharmacy "Carol Davila", Bucharest, Romania
- "Dr. Carol Davila" Teaching Hospital of Nephrology, Bucharest, Romania
| | - Cristina Capusa
- University of Medicine and Pharmacy "Carol Davila", Bucharest, Romania
- "Dr. Carol Davila" Teaching Hospital of Nephrology, Bucharest, Romania
| | - Andreea Radu
- "Dr. Carol Davila" Teaching Hospital of Nephrology, Bucharest, Romania
| | - Gabriel Mircescu
- University of Medicine and Pharmacy "Carol Davila", Bucharest, Romania
- "Dr. Carol Davila" Teaching Hospital of Nephrology, Bucharest, Romania
| | - Gabriel Stefan
- University of Medicine and Pharmacy "Carol Davila", Bucharest, Romania.
- "Dr. Carol Davila" Teaching Hospital of Nephrology, Bucharest, Romania.
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Watanabe K, Okamoto T, Saitou T, Iwasaki A, Matsushita H, Takeuchi K, Asai A, Ito Y, Hara M, Wakatsuki A. Increased urinary albumin leakage is related to injuries of glomerular glycocalyx and podocytes, and associated with tubular dysfunction in preeclampsia. Pregnancy Hypertens 2023; 32:1-6. [PMID: 36801836 DOI: 10.1016/j.preghy.2023.02.001] [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: 08/16/2022] [Revised: 01/29/2023] [Accepted: 02/12/2023] [Indexed: 02/19/2023]
Abstract
OBJECTIVE The pathogenesis of preeclampsia (PE) is known to be endothelial cell damage; however, the existence of dysfunction in glomerular endothelial glycocalyx, podocytes and tubules remains unclear. The glomerular endothelial glycocalyx, basement membrane, podocytes, and tubules are permeability barriers against albumin excretion. This study aimed to assess the relationship between urinary albumin leakage and injuries of the glomerular endothelial glycocalyx, podocytes, and tubules in patients with PE. METHODS A total of 81 women with uncomplicated pregnancies (control, n = 22), PE (PE, n = 36), or gestational hypertension (GH) (GH, n = 23) were enrolled. We assessed urinary albumin and serum hyaluronan for glycocalyx injuries, podocalyxin for podocytes injuries, and urinary N-acetyl-β-d-glucosaminidase (NAG) and liver-type fatty acid-binding protein (l-FABP) for renal tubular dysfunctions. RESULTS The serum hyaluronan and the urinary podocalyxin levels were higher in the PE and GH groups. The urinary NAG and l-FABP levels were higher in the PE group. Urinary NAG and l-FABP levels positively correlated with urinary albumin excretion. CONCLUSIONS Our findings suggest that increased urinary albumin leakage is related to injuries of the glycocalyx and podocytes, and associated with tubular dysfunction in pregnant women with PE. The clinical trial described in this paper was registered at the UMIN Clinical Trials Registry under registration number UMIN000047875. URL of registration: https://centre6.umin.ac.jp/cgi-open-bin/ctr_e/ctr_view.cgi?recptno=R000054437.
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Affiliation(s)
- Kazushi Watanabe
- Department of Obstetrics and Gynecology, School of Medicine, Aichi Medical University, Nagakute, Aichi, Japan.
| | - Tomohito Okamoto
- Department of Obstetrics and Gynecology, School of Medicine, Aichi Medical University, Nagakute, Aichi, Japan
| | - Takuya Saitou
- Department of Obstetrics and Gynecology, School of Medicine, Aichi Medical University, Nagakute, Aichi, Japan
| | - Ai Iwasaki
- Department of Obstetrics and Gynecology, School of Medicine, Aichi Medical University, Nagakute, Aichi, Japan
| | - Hiroshi Matsushita
- Department of Obstetrics and Gynecology, School of Medicine, Aichi Medical University, Nagakute, Aichi, Japan
| | - Kosei Takeuchi
- Department of Medical Cell Biology, School of Medicine, Aichi Medical University, Nagakute, Aichi, Japan
| | - Akimasa Asai
- Department of Nephrology and Rheumatology, School of Medicine, Aichi Medical University, Nagakute, Aichi, Japan
| | - Yasuhiko Ito
- Department of Nephrology and Rheumatology, School of Medicine, Aichi Medical University, Nagakute, Aichi, Japan
| | | | - Akihiko Wakatsuki
- Department of Obstetrics and Gynecology, School of Medicine, Aichi Medical University, Nagakute, Aichi, Japan
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Coppo R, Fervenza FC. Dendrin in IgA nephropathy: protective or marker of early disease? Nephrol Dial Transplant 2023; 38:261-263. [PMID: 36073761 DOI: 10.1093/ndt/gfac258] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2022] [Indexed: 11/13/2022] Open
Affiliation(s)
- Rosanna Coppo
- Fondazione Ricerca Molinette, Regina Margherita Hospital, Turin, Italy
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Proficient Novel Biomarkers Guide Early Detection of Acute Kidney Injury: A Review. Diseases 2022; 11:diseases11010008. [PMID: 36648873 PMCID: PMC9844481 DOI: 10.3390/diseases11010008] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2022] [Revised: 11/12/2022] [Accepted: 11/30/2022] [Indexed: 01/03/2023] Open
Abstract
The definition of acute kidney injury (AKI), despite improvements in criteria, continues to be based on the level of serum creatinine and urinary output that do not specifically indicate tubular function or injury, or glomerular function or injury that is not significant enough to warrant acute hospitalization of the patient. Finding novel biomarkers of AKI has become a major focus nowadays in nephrology to overcome the further complications of end stage renal disease (ESRD). Many compounds, such as KIM 1, IL 18, NGAL, uromodulin, calprotectin, vanin 1, galactin 3, platelet-derived growth factor (PDGF), urinary Na+/H+ exchanger isoform 3 (NHE3), retinol binding protein (RBP) and Cystatin C, are released from the renal tubules and thus any alterations in tubular function can be detected by measuring these parameters in urine. Additionally, glomerular injury can be detected by measuring immunoglobulin G, nephrin, podocalyxin, podocin, transferrin, netrin-1, pyruvate kinase M2, etc. in urine. These novel biomarkers will be useful for timing the initial insult and assessing the duration of AKI. According to available research, these biomarkers could be applied to assess the onset of AKI, distinguishing between kidney injury and dysfunction, directing the management of AKI, and enhancing disease diagnosis. Therefore, we intend to present recent developments in our understanding of significant biomarkers implicated in various aspects of renal damage. Numerous biomarkers are implicated in various pathophysiological processes that follow renal injury, and can improve prognosis and risk classification.
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Yamamoto K, Okabe M, Tanaka K, Yokoo T, Pastan I, Araoka T, Osafune K, Udagawa T, Koizumi M, Matsusaka T. Podocytes are lost from glomeruli before completing apoptosis. Am J Physiol Renal Physiol 2022; 323:F515-F526. [PMID: 36049065 PMCID: PMC9602714 DOI: 10.1152/ajprenal.00080.2022] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2022] [Revised: 08/05/2022] [Accepted: 08/23/2022] [Indexed: 12/14/2022] Open
Abstract
Although apoptosis of podocytes has been widely reported in in vitro studies, it has been less frequently and less definitively documented in in vivo situations. To investigate this discrepancy, we analyzed the dying process of podocytes in vitro and in vivo using LMB2, a human (h)CD25-directed immunotoxin. LMB2 induced cell death within 2 days in 56.8 ± 13.6% of cultured podocytes expressing hCD25 in a caspase-3, Bak1, and Bax-dependent manner. LMB2 induced typical apoptotic features, including TUNEL staining and fragmented nuclei without lactate dehydrogenase leakage. In vivo, LMB2 effectively eliminated hCD25-expressing podocytes in NEP25 mice. Podocytes injured by LMB2 were occasionally stained for cleaved caspase-3 and cleaved lamin A but never for TUNEL. Urinary sediment contained TUNEL-positive podocytes. To examine the effect of glomerular filtration, we performed unilateral ureteral obstruction in NEP25 mice treated with LMB2 1 day before euthanasia. In the obstructed kidney, glomeruli contained significantly more cleaved lamin A-positive podocytes than those in the contralateral kidney (50.1 ± 5.4% vs. 29.3 ± 4.1%, P < 0.001). To further examine the dying process without glomerular filtration, we treated kidney organoids generated from nephron progenitor cells of NEP25 mice with LMB2. Podocytes showed TUNEL staining and nuclear fragmentation. These results indicate that on activation of apoptotic caspases, podocytes are detached and lost in the urine before nuclear fragmentation and that the physical force of glomerular filtration facilitates detachment. This phenomenon may be the reason why definitive apoptosis is not observed in podocytes in vivo.NEW & NOTEWORTHY This report clarifies why morphologically definitive apoptosis is not observed in podocytes in vivo. When caspase-3 is activated in podocytes, these cells are immediately detached from the glomerulus and lost in the urine before DNA fragmentation occurs. Detachment is facilitated by glomerular filtration. This phenomenon explains why podocytes in vivo rarely show TUNEL staining and never apoptotic bodies.
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Affiliation(s)
- Kazuyoshi Yamamoto
- Division of Nephrology and Hypertension, Department of Internal Medicine, The Jikei University School of Medicine, Tokyo, Japan
- Department of Basic Medicine, Tokai University School of Medicine, Isehara, Japan
| | - Masahiro Okabe
- Division of Nephrology and Hypertension, Department of Internal Medicine, The Jikei University School of Medicine, Tokyo, Japan
- Department of Basic Medicine, Tokai University School of Medicine, Isehara, Japan
| | - Keiko Tanaka
- Department of Basic Medicine, Tokai University School of Medicine, Isehara, Japan
| | - Takashi Yokoo
- Division of Nephrology and Hypertension, Department of Internal Medicine, The Jikei University School of Medicine, Tokyo, Japan
| | - Ira Pastan
- Laboratory of Molecular Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, Maryland
| | - Toshikazu Araoka
- Center for iPS Cell Research and Application, Kyoto University, Kyoto, Japan
| | - Kenji Osafune
- Center for iPS Cell Research and Application, Kyoto University, Kyoto, Japan
| | - Tomohiro Udagawa
- Department of Basic Medicine, Tokai University School of Medicine, Isehara, Japan
| | - Masahiro Koizumi
- Department of Internal Medicine, Tokai University School of Medicine, Isehara, Japan
| | - Taiji Matsusaka
- Department of Basic Medicine, Tokai University School of Medicine, Isehara, Japan
- Institute of Medical Science, Tokai University School of Medicine, Isehara, Japan
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Exfoliated Kidney Cells from Urine for Early Diagnosis and Prognostication of CKD: The Way of the Future? Int J Mol Sci 2022; 23:ijms23147610. [PMID: 35886957 PMCID: PMC9324667 DOI: 10.3390/ijms23147610] [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: 05/30/2022] [Revised: 07/07/2022] [Accepted: 07/08/2022] [Indexed: 11/17/2022] Open
Abstract
Chronic kidney disease (CKD) is a global health issue, affecting more than 10% of the worldwide population. The current approach for formal diagnosis and prognostication of CKD typically relies on non-invasive serum and urine biomarkers such as serum creatinine and albuminuria. However, histological evidence of tubulointerstitial fibrosis is the 'gold standard' marker of the likelihood of disease progression. The development of novel biomedical technologies to evaluate exfoliated kidney cells from urine for non-invasive diagnosis and prognostication of CKD presents opportunities to avoid kidney biopsy for the purpose of prognostication. Efforts to apply these technologies more widely in clinical practice are encouraged, given their potential as a cost-effective approach, and no risk of post-biopsy complications such as bleeding, pain and hospitalization. The identification of biomarkers in exfoliated kidney cells from urine via western blotting, enzyme-linked immunosorbent assay (ELISA), immunofluorescence techniques, measurement of cell and protein-specific messenger ribonucleic acid (mRNA)/micro-RNA and other techniques have been reported. Recent innovations such as multispectral autofluorescence imaging and single-cell RNA sequencing (scRNA-seq) have brought additional dimensions to the clinical application of exfoliated kidney cells from urine. In this review, we discuss the current evidence regarding the utility of exfoliated proximal tubule cells (PTC), podocytes, mesangial cells, extracellular vesicles and stem/progenitor cells as surrogate markers for the early diagnosis and prognostication of CKD. Future directions for development within this research area are also identified.
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Zhao J, Liu H. Mechanism for the therapeutic effect of Tripterygium wilfordii Hook. f. preparations on IgA nephropathy. ZHONG NAN DA XUE XUE BAO. YI XUE BAN = JOURNAL OF CENTRAL SOUTH UNIVERSITY. MEDICAL SCIENCES 2022; 47:573-582. [PMID: 35753727 PMCID: PMC10929912 DOI: 10.11817/j.issn.1672-7347.2022.210410] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Received: 06/29/2021] [Indexed: 06/15/2023]
Abstract
Tripterygium wilfordii Hook. f. is a traditional Chinese herbal medicine. The bioactive compounds from Tripterygium wilfordii Hook. f. have unique immunosuppressive and anti-inflammatory effects, and can exert their pharmacological effects through multi-target and multi-channel. Tripterygium wilfordii Hook. f. preparations have been used in IgA nephropathy (IgAN) for many years and are well accepted for good curative effects. However, the underlying mechanisms are still unclear. It is valuable to summarize the current progress in clinical application of Tripterygium wilfordii Hook. f. preparations in IgAN and other kidney diseases. We discussed the component characteristics, efficacies in reducing urinary protein levels and protecting renal function, as well as the side effects. As for the mechanisms, we should focus on all links of IgAN pathogenesis, including reducing the production of pathogenic IgA, decreasing renal inflammation and fibrosis, and protecting podocytes. As a representative drugs with clear efficacy and potential toxicity, Tripterygium wilfordii Hook. f. preparations need more in-depth basic and clinical research to improve their efficacy and safety.
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Affiliation(s)
- Juanyong Zhao
- Department of Nephrology, Second Xiangya Hospital, Central South University; Key Laboratory of Kidney Disease and Blood Purification of Hunan Province, Changsha 410011, China.
| | - Hong Liu
- Department of Nephrology, Second Xiangya Hospital, Central South University; Key Laboratory of Kidney Disease and Blood Purification of Hunan Province, Changsha 410011, China.
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Mallela SK, Merscher S, Fornoni A. Implications of Sphingolipid Metabolites in Kidney Diseases. Int J Mol Sci 2022; 23:ijms23084244. [PMID: 35457062 PMCID: PMC9025012 DOI: 10.3390/ijms23084244] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2022] [Revised: 04/08/2022] [Accepted: 04/10/2022] [Indexed: 12/18/2022] Open
Abstract
Sphingolipids, which act as a bioactive signaling molecules, are involved in several cellular processes such as cell survival, proliferation, migration and apoptosis. An imbalance in the levels of sphingolipids can be lethal to cells. Abnormalities in the levels of sphingolipids are associated with several human diseases including kidney diseases. Several studies demonstrate that sphingolipids play an important role in maintaining proper renal function. Sphingolipids can alter the glomerular filtration barrier by affecting the functioning of podocytes, which are key cellular components of the glomerular filtration barrier. This review summarizes the studies in our understanding of the regulation of sphingolipid signaling in kidney diseases, especially in glomerular and tubulointerstitial diseases, and the potential to target sphingolipid pathways in developing therapeutics for the treatment of renal diseases.
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Affiliation(s)
- Shamroop kumar Mallela
- Katz Family Division of Nephrology and Hypertension, Department of Medicine, Miller School of Medicine, University of Miami, Miami, FL 33136, USA;
- Peggy and Harold Katz Family Drug Discovery Center, Miller School of Medicine, University of Miami, Miami, FL 33136, USA
| | - Sandra Merscher
- Katz Family Division of Nephrology and Hypertension, Department of Medicine, Miller School of Medicine, University of Miami, Miami, FL 33136, USA;
- Peggy and Harold Katz Family Drug Discovery Center, Miller School of Medicine, University of Miami, Miami, FL 33136, USA
- Correspondence: (S.M.); (A.F.); Tel.: +1-305-243-6567 (S.M.); +1-305-243-3583 (A.F.); Fax: +1-305-243-3209 (S.M.); +1-305-243-3506 (A.F.)
| | - Alessia Fornoni
- Katz Family Division of Nephrology and Hypertension, Department of Medicine, Miller School of Medicine, University of Miami, Miami, FL 33136, USA;
- Peggy and Harold Katz Family Drug Discovery Center, Miller School of Medicine, University of Miami, Miami, FL 33136, USA
- Correspondence: (S.M.); (A.F.); Tel.: +1-305-243-6567 (S.M.); +1-305-243-3583 (A.F.); Fax: +1-305-243-3209 (S.M.); +1-305-243-3506 (A.F.)
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Mizdrak M, Kumrić M, Kurir TT, Božić J. Emerging Biomarkers for Early Detection of Chronic Kidney Disease. J Pers Med 2022; 12:jpm12040548. [PMID: 35455664 PMCID: PMC9025702 DOI: 10.3390/jpm12040548] [Citation(s) in RCA: 22] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2022] [Revised: 03/22/2022] [Accepted: 03/28/2022] [Indexed: 12/14/2022] Open
Abstract
Chronic kidney disease (CKD) is a major and serious global health problem that leads to kidney damage as well as multiple systemic diseases. Early diagnosis and treatment are two major measures to prevent further deterioration of kidney function and to delay adverse outcomes. However, the paucity of early, predictive and noninvasive biomarkers has undermined our ability to promptly detect and treat this common clinical condition which affects more than 10% of the population worldwide. Despite all limitations, kidney function is still measured by serum creatinine, cystatin C, and albuminuria, as well as estimating glomerular filtration rate using different equations. This review aims to provide comprehensive insight into diagnostic methods available for early detection of CKD. In the review, we discuss the following topics: (i) markers of glomerular injury; (ii) markers of tubulointerstitial injury; (iii) the role of omics; (iv) the role of microbiota; (v) and finally, the role of microRNA in the early detection of CKD. Despite all novel findings, none of these biomarkers have met the criteria of an ideal early marker. Since the central role in CKD progression is the proximal tubule (PT), most data from the literature have analyzed biomarkers of PT injury, such as KIM-1 (kidney injury molecule-1), NGAL (neutrophil gelatinase-associated lipocalin), and L-FABP (liver fatty acid-binding protein).
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Affiliation(s)
- Maja Mizdrak
- Department of Nephrology and Hemodialysis, University Hospital of Split, 21000 Split, Croatia;
- Department of Pathophysiology, University of Split School of Medicine, 21000 Split, Croatia; (M.K.); (T.T.K.)
| | - Marko Kumrić
- Department of Pathophysiology, University of Split School of Medicine, 21000 Split, Croatia; (M.K.); (T.T.K.)
| | - Tina Tičinović Kurir
- Department of Pathophysiology, University of Split School of Medicine, 21000 Split, Croatia; (M.K.); (T.T.K.)
- Department of Endocrinology, Diabetes and Metabolic Disorders, University Hospital of Split, 21000 Split, Croatia
| | - Joško Božić
- Department of Pathophysiology, University of Split School of Medicine, 21000 Split, Croatia; (M.K.); (T.T.K.)
- Correspondence:
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Li Q, Zhu L, Shi S, Xu D, Lv J, Zhang H. Case Report: A Pathogenic Missense Variant of WT1 Cosegregates With Proteinuria in a Six-Generation Chinese Family With IgA Nephropathy. Front Med (Lausanne) 2022; 8:810940. [PMID: 35174184 PMCID: PMC8841721 DOI: 10.3389/fmed.2021.810940] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2021] [Accepted: 12/30/2021] [Indexed: 11/13/2022] Open
Abstract
Immunoglobulin A (IgA) nephropathy (IgAN) is the most common type of primary glomerulonephritis worldwide. In addition to hematuria, proteinuria is observed in a considerable proportion of patients with IgAN and has proven to be a strong risk factor for disease progression. Although the exact pathogenesis of IgAN is still unclear, genetic factors are widely considered to play a role in its occurrence and development. Here, we investigated a large IgAN-associated pedigree of 47 members belonging to six generations. Two members of the family who presented with proteinuria and hematuria were diagnosed with IgAN through renal biopsy. Four other members also exhibited proteinuria or hematuria but without renal biopsy. Using whole-exome sequencing, we identified a likely pathogenic variant in WT1 (c.1397C>T; p.Ser466Phe) that cosegregated with proteinuria in the affected family members. In addition, another pathogenic variant in NPHS1 (c.3478C>T; p.Arg1160Ter) was identified; however, it did not cosegregate with abnormal proteinuria. Compared to individuals in the pedigree with only one heterozygous WT1 variant (c.1397C>T; p.Ser466Phe), the proband and her younger brother carried an additional WT1 variant (c.1433-10G>A) and presented with a more severe phenotype and rapid progression to end-stage kidney disease. Our findings suggest the WT1 missense variant (c.1397C>T; p.Ser466Phe)-induced primary podocyte injury might contribute to the proteinuria phenotype and IgAN progression in this pedigree.
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Inoue K. Urinary Podocyte Biomarkers and Glomerular Histologic Change. KIDNEY360 2022; 3:407-409. [PMID: 35582191 PMCID: PMC9034819 DOI: 10.34067/kid.0008212021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/18/2022] [Accepted: 01/20/2022] [Indexed: 01/10/2023]
Affiliation(s)
- Kazunori Inoue
- Department of Nephrology, Osaka University Graduate School of Medicine, Osaka, Japan
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Kabasawa K, Hosojima M, Ito Y, Matsushima K, Tanaka J, Hara M, Nakamura K, Narita I, Saito A. Association of metabolic syndrome traits with urinary biomarkers in Japanese adults. Diabetol Metab Syndr 2022; 14:9. [PMID: 35033174 PMCID: PMC8760661 DOI: 10.1186/s13098-021-00779-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/19/2021] [Accepted: 12/28/2021] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Although metabolic syndrome traits are risk factors for chronic kidney disease, few studies have examined their association with urinary biomarkers. METHODS Urinary biomarkers, including A-megalin, C-megalin, podocalyxin, albumin, α1-microglobulin, β2-microglobulin, and N-acetyl-β-D-glucosaminidase, were cross-sectionally assessed in 347 individuals (52.7% men) with a urine albumin-to-creatinine ratio (ACR) < 300 mg/g in a health checkup. Metabolic syndrome traits were adopted from the National Cholesterol Education Program (third revision) of the Adult Treatment Panel criteria modified for Asians. RESULTS Participants had a mean body mass index, estimated glomerular filtration rate (eGFR), and median ACR of 23.0 kg/m2, 74.8 mL/min/1.73 m2, and 7.5 mg/g, respectively. In age- and sex-adjusted logistic regression analysis, A-megalin and albumin were significantly associated with the clustering number of metabolic syndrome traits (3 or more). After further adjustment with eGFR, higher quartiles of A-megalin and albumin were each independently associated with the clustering number of metabolic syndrome traits (adjusted odds ratio for A-megalin: 1.30 per quartile, 95% CI 1.03-1.64; albumin: 1.42 per quartile, 95% CI 1.12-1.79). CONCLUSIONS Both urinary A-megalin and albumin are associated with the clustering number of metabolic syndrome traits. Further research on urinary A-megalin is warranted to examine its role as a potential marker of kidney damage from metabolic risk factors.
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Affiliation(s)
- Keiko Kabasawa
- Department of Health Promotion Medicine, Niigata University Graduate School of Medical and Dental Sciences, Niigata, Japan.
- Division of Clinical Nephrology and Rheumatology, Kidney Research Center, Niigata University Graduate School of Medical and Dental Sciences, Niigata, Japan.
| | - Michihiro Hosojima
- Department of Clinical Nutrition Science, Kidney Research Center, Niigata University Graduate School of Medical and Dental Sciences, Niigata, Japan
| | - Yumi Ito
- Department of Health Promotion Medicine, Niigata University Graduate School of Medical and Dental Sciences, Niigata, Japan
- Division of Clinical Nephrology and Rheumatology, Kidney Research Center, Niigata University Graduate School of Medical and Dental Sciences, Niigata, Japan
| | | | - Junta Tanaka
- Department of Health Promotion Medicine, Niigata University Graduate School of Medical and Dental Sciences, Niigata, Japan
| | | | - Kazutoshi Nakamura
- Division of Preventive Medicine, Niigata University Graduate School of Medical and Dental Sciences, Niigata, Japan
| | - Ichiei Narita
- Department of Health Promotion Medicine, Niigata University Graduate School of Medical and Dental Sciences, Niigata, Japan
- Division of Clinical Nephrology and Rheumatology, Kidney Research Center, Niigata University Graduate School of Medical and Dental Sciences, Niigata, Japan
| | - Akihiko Saito
- Department of Applied Molecular Medicine, Kidney Research Center, Niigata University Graduate School of Medical and Dental Sciences, Niigata, Japan
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Yu F, Zhu X, Yuan S, Chen X, Li Z, Qu Z, Liu H, Sun L, Liu F. Predictive value of sub classification of focal segmental glomerular sclerosis in Oxford classification of IgA nephropathy. Ann Med 2021; 53:587-595. [PMID: 33825605 PMCID: PMC8032344 DOI: 10.1080/07853890.2021.1897664] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
BACKGROUND The Oxford classification of IgA nephropathy (IgAN) was revised in 2016 which lacked sufficient evidence for prognostic value of subclassification of focal segmental glomerular sclerosis (S lesion), and the proper proportion of S lesion for subclassification remains undetermined. AIM This study aimed to explore the predictive value of the new subclassification of S score on renal outcomes of IgAN patients. METHODS 348 patients with IgAN-associated S lesion were enrolled. According to the optimal cut-off of 25% established by receiver operating characteristic (ROC) curves, we divided S1 patients into two groups: S1a group (S lesion < 25%) and S1b group (S lesion ≥ 25%). IgAN patients with mild lesion (M0E0S0T0C0) were set as the control group. The clinical features at renal biopsy, pathological findings, and follow-up parameters (follow-up time ranged from 1 to 5 years) were collected. We used univariate and multivariate analyses to assess whether the subclassification of S score could refine risk prediction and clinical utility. RESULTS We demonstrated that S lesion ≥ 25% was associated with a more rapid GFR loss and a lower rate of complete remission of proteinuria even adjusted for multiple clinic pathological variables, compared to S1a group (All p values <.05). And the ratio of glomeruli with T lesion and crescents were higher in patients with S lesion ≥ 25%. Data showed that IgAN patients with S lesion ≥ 25% were at an increased risk of poor renal outcomes even with immunosuppression. CONCLUSION This study might recommend new subclassification of S scores (S0 (no S lesion), S1 (S lesion <25% of glomeruli), and S2 (S lesion ≥ 25% of glomeruli)) for the Oxford classification. This model may also help to evaluate pros and cons of immunosuppressive therapy in IgAN patients with different level of S lesion.KEY MESSAGESS lesion ≥ 25% is an independent risk factor for poor renal outcome in IgAN patients.This new subclassification of S scores may help to evaluate pros and cons of immunotherapy in IgAN patients with different level of S lesion.
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Affiliation(s)
- Fang Yu
- Department of Nephrology, The Second Xiangya Hospital of Central South University; Hunan Key Laboratory of Kidney Disease and Blood Purification, Changsha, China.,Department of Nephrology, Army Medical Center, Chongqing, China
| | - Xuejing Zhu
- Department of Nephrology, The Second Xiangya Hospital of Central South University; Hunan Key Laboratory of Kidney Disease and Blood Purification, Changsha, China
| | - Shuguang Yuan
- Department of Nephrology, The Second Xiangya Hospital of Central South University; Hunan Key Laboratory of Kidney Disease and Blood Purification, Changsha, China
| | - Xiaojun Chen
- Department of Nephrology, The Second Xiangya Hospital of Central South University; Hunan Key Laboratory of Kidney Disease and Blood Purification, Changsha, China
| | - Zheng Li
- Department of Nephrology, The Second Xiangya Hospital of Central South University; Hunan Key Laboratory of Kidney Disease and Blood Purification, Changsha, China
| | - Zhong Qu
- Department of emergency surgery, Changsha Central Hospital, Changsha, China
| | - Hong Liu
- Department of Nephrology, The Second Xiangya Hospital of Central South University; Hunan Key Laboratory of Kidney Disease and Blood Purification, Changsha, China
| | - Lin Sun
- Department of Nephrology, The Second Xiangya Hospital of Central South University; Hunan Key Laboratory of Kidney Disease and Blood Purification, Changsha, China
| | - Fuyou Liu
- Department of Nephrology, The Second Xiangya Hospital of Central South University; Hunan Key Laboratory of Kidney Disease and Blood Purification, Changsha, China
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18
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Urinary podocyte markers in kidney diseases. Clin Chim Acta 2021; 523:315-324. [PMID: 34666027 DOI: 10.1016/j.cca.2021.10.017] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2021] [Revised: 09/17/2021] [Accepted: 10/13/2021] [Indexed: 01/19/2023]
Abstract
Podocytes play an important role in the maintenance of kidney function, and they are the primary focus of many kidney diseases. Podocyte injury results in the shedding of podocyte-derived cellular fragments and podocyte-specific molecular targets into the urine, which may serve as biomarkers of kidney diseases. Intact podocytes, either viable or dead, and podocyte-derived microvesicles could be quantified in the urine by various centrifugation, visualization and culture methods. Podocyte-specific protein targets from the nucleus, cytoplasm, slit-diaphragm, glomerular capillary basement membrane, and cytoskeleton, as well as their corresponding messenger RNA (mRNA), in the urine could be quantified by western blotting, ELISA, or quantitative polymerase chain reaction. Although some of these techniques may be expensive or labor-intensive at present, they may become widely available in the future because of the improvement in technology and automation. The application of urinary podocyte markers for the diagnosis and monitoring of various kidney diseases have been explored but the published data in this area are not sufficiently systematic and lack external validation. Further research should focus on standardizing, comparing, and automizing laboratory methods, as well as defining their added value to the routine clinical tests.
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19
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Chang M, Yang B, Li L, Si Y, Zhao M, Hao W, Zhao J, Zhang Y. Modified Huangqi Chifeng Decoction Attenuates Proteinuria by Reducing Podocyte Injury in a Rat Model of Immunoglobulin a Nephropathy. Front Pharmacol 2021; 12:714584. [PMID: 34381367 PMCID: PMC8350133 DOI: 10.3389/fphar.2021.714584] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2021] [Accepted: 07/14/2021] [Indexed: 02/05/2023] Open
Abstract
Modified Huangqi Chifeng decoction (MHCD) has been used to reduce proteinuria in immunoglobulin A nephropathy (IgAN) for many years. Previously, we have demonstrated its protective role in glomerular mesangial cells. Podocyte injury, another key factor associated with proteinuria in IgAN, has also attracted increasing attention. However, whether MHCD can reduce proteinuria by protecting podocytes remains unclear. The present study aimed to investigate the protective effects of MHCD against podocyte injury in a rat model of IgAN. To establish the IgAN model, rats were administered bovine serum albumin, carbon tetrachloride, and lipopolysaccharide. MHCD in three doses or telmisartan was administered once daily for 8 weeks (n = 10 rats/group). Rats with IgAN developed proteinuria at week 6, which worsened over time until drug intervention. After drug intervention, MHCD reduced proteinuria and had no effect on liver and kidney function. Furthermore, MHCD alleviated renal pathological lesions, hyperplasia of mesangial cells, mesangial matrix expansion, and podocyte foot process fusion. Western blot analysis revealed that MHCD increased the expression of the podocyte-associated proteins nephrin and podocalyxin. Additionally, we stained podocyte nuclei with an antibody for Wilms’ tumor protein one and found that MHCD increased the podocyte number in rats with IgAN. In conclusion, these results demonstrate that MHCD attenuates proteinuria by reducing podocyte injury.
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Affiliation(s)
- Meiying Chang
- Department of Nephrology, Xiyuan Hospital, China Academy of Chinese Medical Sciences, Beijing, China
| | - Bin Yang
- Department of Pathology, Xiyuan Hospital, China Academy of Chinese Medical Sciences, Beijing, China
| | - Liusheng Li
- Department of Nephrology, Xiyuan Hospital, China Academy of Chinese Medical Sciences, Beijing, China
| | - Yuan Si
- Department of Nephrology, Xiyuan Hospital, China Academy of Chinese Medical Sciences, Beijing, China
| | - Mingming Zhao
- Department of Nephrology, Xiyuan Hospital, China Academy of Chinese Medical Sciences, Beijing, China
| | - Wei Hao
- Medical Animal Experimental Center, Xiyuan Hospital, China Academy of Chinese Medical Sciences, Beijing, China
| | - Jinning Zhao
- Medical Animal Experimental Center, Xiyuan Hospital, China Academy of Chinese Medical Sciences, Beijing, China
| | - Yu Zhang
- Department of Nephrology, Xiyuan Hospital, China Academy of Chinese Medical Sciences, Beijing, China
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Farzamikia N, Baradaran B, Mostafavi S, Ahmadian E, Hosseiniyan Khatibi SM, Zununi Vahed S, Ardalan M. Podocyte-derived microparticles in IgA nephropathy. Biomed Pharmacother 2021; 141:111891. [PMID: 34237594 DOI: 10.1016/j.biopha.2021.111891] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2021] [Revised: 06/06/2021] [Accepted: 06/28/2021] [Indexed: 12/21/2022] Open
Abstract
Microparticles are a general term for different types of cell plasma membrane-originated vesicles that are released into the extracellular environment. The paracrine action of these nano-sized vesicles is crucial for intercellular communications through the transfer of diverse lipids, cytosolic proteins, RNA as well as microRNAs. The progression of different diseases influences the composition, occurrence, and functions of these cell-derived particles. Podocyte injury has been shown to have an important role in the pathophysiology of many glomerular diseases including IgA nephropathy (IgAN). This review would focus on the possible potential of podocyte-derived microparticles detected in urine to be used as a diagnostic tool in IgAN.
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Affiliation(s)
- Negin Farzamikia
- Kidney Research Center, Tabriz University of Medical Sciences, Tabriz, Iran; Student Research Committee, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Behzad Baradaran
- Immunology Research Center, Faculty of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Soroush Mostafavi
- Kidney Research Center, Tabriz University of Medical Sciences, Tabriz, Iran; Student Research Committee, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Elham Ahmadian
- Kidney Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
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21
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Selvaskandan H, Shi S, Twaij S, Cheung CK, Barratt J. Monitoring Immune Responses in IgA Nephropathy: Biomarkers to Guide Management. Front Immunol 2020; 11:572754. [PMID: 33123151 PMCID: PMC7572847 DOI: 10.3389/fimmu.2020.572754] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2020] [Accepted: 09/17/2020] [Indexed: 11/13/2022] Open
Abstract
IgA nephropathy (IgAN) is the commonest biopsy-reported primary glomerulonephritis worldwide. It has an incidence which peaks among young adults, and 30 to 40% of patients' progress to end stage kidney disease within twenty years of diagnosis. Ten-year kidney survival rates have been reported to be as low as 35% in some parts of the world. The successful management of IgAN is limited by an incomplete understanding of the pathophysiology of IgAN and a poor understanding of how pathophysiology may vary both from patient to patient and between patient groups, particularly across races. This is compounded by a lack of rigorously designed and delivered clinical trials in IgAN. This is slowly changing, with a number of Phase 2 and 3 clinical trials of novel therapies targeting a number of different putative pathogenic pathways in IgAN due to report in the next 5 years. From our current, albeit limited, understanding of the pathophysiology of IgAN it is unlikely a single therapy will be effective in all patients with IgAN. The successful management of IgAN in the future is, therefore, likely to be reliant on targeted therapies, carefully selected based on an individualized understanding of a patient's risk of progression and underlying pathophysiology. The potential role of biomarkers to facilitate personalization of prognostication and treatment of IgAN is immense. Here we review the progress made over the past decade in identifying and validating new biomarkers, with a particular focus on those that reflect immunological responses in IgAN.
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Affiliation(s)
- Haresh Selvaskandan
- Mayer IgA Nephropathy Laboratories, Department of Cardiovascular Sciences, University of Leicester, Leicester, United Kingdom
| | - Sufang Shi
- Mayer IgA Nephropathy Laboratories, Department of Cardiovascular Sciences, University of Leicester, Leicester, United Kingdom
| | - Sara Twaij
- Mayer IgA Nephropathy Laboratories, Department of Cardiovascular Sciences, University of Leicester, Leicester, United Kingdom
| | - Chee Kay Cheung
- Mayer IgA Nephropathy Laboratories, Department of Cardiovascular Sciences, University of Leicester, Leicester, United Kingdom
| | - Jonathan Barratt
- Mayer IgA Nephropathy Laboratories, Department of Cardiovascular Sciences, University of Leicester, Leicester, United Kingdom
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22
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High glucose provokes microvesicles generation from glomerular podocytes via NOX4/ROS pathway. Biosci Rep 2020; 39:220961. [PMID: 31664454 PMCID: PMC6863764 DOI: 10.1042/bsr20192554] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2019] [Revised: 09/12/2019] [Accepted: 10/21/2019] [Indexed: 01/03/2023] Open
Abstract
Microvesicles (MVs) were involved in the pathogenesis of many diseases, such as cardiovascular diseases and diabetes. Oxidative stress played a key role in the development and progression of diabetic nephropathy (DN). Our aim of the present study was to investigate whether high glucose (HG) could provoke MVs generation from podocytes and its potential mechanism. Mouse podocyte clone 5 (MPC-5) was stimulated by HG. The intracellular reactive oxygen species (ROS) of podocytes were measured by fluorescence microscopy with the probe of CM-H2DCFDA and MitoSOX™. Antioxidants N-Acetyl-l-cysteine (NAC) and α lipoic acid (α-LA) were used to treat podocytes after HG stimulation. The rate of podocyte apoptosis was evaluated with Annexin V-FITC by flow cytometry. NOX4 expression was examined and siRNA were performed to explore the mechanism of MVs generation. The quantities of MVs from MPC-5 cells was significantly increased (P<0.05) by 4.6-times after 30 mM glucose stimulation, accompanied with double increased apoptosis. Cellular ROS generation was increased by HG at the peak of 48 h stimulation. HG-induced MVs were significantly decreased by 52.9% after pretreatment by antioxidant NAC. Nevertheless, mitochondrial ROS in podocytes reached a peak at 4 h stimulation, but specific antioxidant α-LA had no effect on the production of MVs (P>0.05). Levels of NOX4 mRNA and protein expression were significantly up-regulated by HG (P<0.05). Podocyte-derived MVs by HG were eliminated by NOX4 siRNA. HG can provoke MVs generation from glomerular podocytes through ROS/NOX4 pathway, not from mitochondrial pathway.
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Liao Y, Wang Z, Wang L, Lin Y, Ye Z, Zeng X, Wei F. MicroRNA-27a-3p directly targets FosB to regulate cell proliferation, apoptosis, and inflammation responses in immunoglobulin a nephropathy. Biochem Biophys Res Commun 2020; 529:1124-1130. [PMID: 32819575 DOI: 10.1016/j.bbrc.2020.06.115] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2020] [Accepted: 06/23/2020] [Indexed: 01/08/2023]
Abstract
Immunoglobulin A nephropathy (IgAN) constitutes the most common primary glomerulonephritis worldwide; however, the exact pathogenesis of IgAN is unknown. Previous genome-wide analysis of microRNA (miRNA) expression in the kidney has confirmed that miRNAs are closely related to the pathological changes of IgAN. Accordingly, in this study we found that miR-27a-3p is upregulated in IgAN kidney tissues in addition to human podocytes and tubule epithelial HK2 but not mesangial cells. Methylthiazolyldiphenyl-tetrazolium bromide (MTT), flow cytometry, real-time polymerase chain reaction, western blot, and enzyme-linked immunosorbent assays were used to verify the regulatory effects of miR-27a-3p and its inhibition on cell proliferation, apoptosis, and release of inflammatory factors in podocytes and HK2 cells. The target genes of miR-27a-3p were predicted using bioinformatics software; the identity of FosB as a target gene of miR-27a-3p was confirmed by luciferase report assay and western blot. Overall, our findings demonstrated that miR-27a-3p regulates cell apoptosis, cell proliferation, and the release of inflammatory cytokines of human podocytes and HK2 cells by directly targeting FosB. Our results therefore suggested that miR-27a-3p might be associated with the pathophysiology of IgAN and may represent a potential target for further studies related to IgAN mechanism or therapeutics.
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Affiliation(s)
- Yu Liao
- 2nd Clinical Medical College of Guangzhou University of Chinese Medicine, Guangzhou, 510405, China; Guangdong Hospital of Traditional Chinese Medicine, Guangzhou, 510120, China
| | - Ziyan Wang
- 2nd Clinical Medical College of Guangzhou University of Chinese Medicine, Guangzhou, 510405, China; General Hospital of Guangzhou Military Command of PLA, Guangzhou, 510062, China
| | - Lixin Wang
- Guangdong Hospital of Traditional Chinese Medicine, Guangzhou, 510120, China; 2nd Clinical Hospital of Guangzhou University of Chinese Medicine, Guangzhou, 510062, China
| | - Yanzhao Lin
- Guangdong Hospital of Traditional Chinese Medicine, Guangzhou, 510120, China; 2nd Clinical Hospital of Guangzhou University of Chinese Medicine, Guangzhou, 510062, China
| | - Ziyi Ye
- Guangdong Hospital of Traditional Chinese Medicine, Guangzhou, 510120, China; 2nd Clinical Hospital of Guangzhou University of Chinese Medicine, Guangzhou, 510062, China
| | - Xufang Zeng
- Guangdong Hospital of Traditional Chinese Medicine, Guangzhou, 510120, China; 2nd Clinical Hospital of Guangzhou University of Chinese Medicine, Guangzhou, 510062, China
| | - Fangning Wei
- Guangdong Hospital of Traditional Chinese Medicine, Guangzhou, 510120, China; 2nd Clinical Hospital of Guangzhou University of Chinese Medicine, Guangzhou, 510062, China.
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Association between Renal Podocalyxin Expression and Renal Dysfunction in Patients with Diabetic Nephropathy: A Single-Center, Retrospective Case-Control Study. BIOMED RESEARCH INTERNATIONAL 2020; 2020:7350781. [PMID: 32337271 PMCID: PMC7157790 DOI: 10.1155/2020/7350781] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/27/2019] [Revised: 01/23/2020] [Accepted: 02/12/2020] [Indexed: 01/16/2023]
Abstract
This retrospective study investigated whether podocalyxin expression in renal biopsies and urine of patients with diabetic nephropathy (DN) is associated with renal function. This retrospective study included 32 patients with nephropathy, secondary to type 2 diabetes treated at the First Hospital of Lanzhou University (January 2010 to January 2015). Compared with the control group, the DN group had a significantly lower renal expression of podocalyxin and higher urinary podocalyxin/creatinine ratio. Patients with DN were divided into the high and low expression groups according to podocalyxin expression in renal tissues. Patients in the low expression group had longer diabetes duration, lower plasma albumin and eGFR, higher glycated hemoglobin (HbA1c), 24 h urinary protein, serum creatinine, and urinary podocalyxin/creatinine ratio, and more severe glomerular, tubulointerstitial, and renal interstitial inflammation than patients in the high expression group (all P < 0.01). The renal survival rate was significantly lower in the low expression group than in the high expression group (P < 0.01). Single-factor Cox regression analysis showed that reduced podocalyxin expression and increased urinary podocalyxin excretion were associated with poor renal outcome. Measuring podocalyxin levels in renal tissues and urine could help evaluate the progression of DN.
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Goerlich N, Brand HA, Langhans V, Tesch S, Schachtner T, Koch B, Paliege A, Schneider W, Grützkau A, Reinke P, Enghard P. Kidney transplant monitoring by urinary flow cytometry: Biomarker combination of T cells, renal tubular epithelial cells, and podocalyxin-positive cells detects rejection. Sci Rep 2020; 10:796. [PMID: 31964937 PMCID: PMC6972704 DOI: 10.1038/s41598-020-57524-7] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2019] [Accepted: 12/31/2019] [Indexed: 01/19/2023] Open
Abstract
Creatinine and proteinuria are used to monitor kidney transplant patients. However, renal biopsies are needed to diagnose renal graft rejection. Here, we assessed whether the quantification of different urinary cells would allow non-invasive detection of rejection. Urinary cell numbers of CD4+ and CD8+ T cells, monocytes/macrophages, tubular epithelial cells (TEC), and podocalyxin(PDX)-positive cells were determined using flow cytometry and were compared to biopsy results. Urine samples of 63 renal transplant patients were analyzed. Patients with transplant rejection had higher amounts of urinary T cells than controls; however, patients who showed worsening graft function without rejection had similar numbers of T cells. T cells correlated with histological findings (interstitial inflammation p = 0.0005, r = 0.70; tubulitis p = 0.006, r = 0.58). Combining the amount of urinary T cells and TEC, or T cells and PDX+ cells, yielded a significant segregation of patients with rejection from patients without rejection (all p < 0.01, area under the curve 0.89–0.91). Urinary cell populations analyzed by flow cytometry have the potential to introduce new monitoring methods for kidney transplant patients. The combination of urinary T cells, TEC, and PDX-positive cells may allow non-invasive detection of transplant rejection.
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Affiliation(s)
| | | | | | | | | | - Benjamin Koch
- Goethe University Hospital Frankfurt, Frankfurt, Germany
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Taherkhani A, Farrokhi Yekta R, Mohseni M, Saidijam M, Arefi Oskouie A. Chronic kidney disease: a review of proteomic and metabolomic approaches to membranous glomerulonephritis, focal segmental glomerulosclerosis, and IgA nephropathy biomarkers. Proteome Sci 2019; 17:7. [PMID: 31889913 PMCID: PMC6925425 DOI: 10.1186/s12953-019-0155-y] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2019] [Accepted: 12/12/2019] [Indexed: 12/12/2022] Open
Abstract
Chronic Kidney Disease (CKD) is a global health problem annually affecting millions of people around the world. It is a comprehensive syndrome, and various factors may contribute to its occurrence. In this study, it was attempted to provide an accurate definition of chronic kidney disease; followed by focusing and discussing on molecular pathogenesis, novel diagnosis approaches based on biomarkers, recent effective antigens and new therapeutic procedures related to high-risk chronic kidney disease such as membranous glomerulonephritis, focal segmental glomerulosclerosis, and IgA nephropathy, which may lead to end-stage renal diseases. Additionally, a considerable number of metabolites and proteins that have previously been discovered and recommended as potential biomarkers of various CKDs using ‘-omics-’ technologies, proteomics, and metabolomics were reviewed.
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Affiliation(s)
- Amir Taherkhani
- 1Research Center for Molecular Medicine, Hamadan University of Medical Sciences, Hamadan, Iran
| | | | - Maede Mohseni
- 3Urology and Nephrology Research Center, Hamadan University of Medical Sciences, Hamadan, Iran
| | - Massoud Saidijam
- 1Research Center for Molecular Medicine, Hamadan University of Medical Sciences, Hamadan, Iran
| | - Afsaneh Arefi Oskouie
- 4Department of Basic Sciences, Faculty of Paramedical Sciences, Shahid Beheshti University of Medical Sciences, Tehran, Iran
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Ma H, Xu Y, Zhang R, Guo B, Zhang S, Zhang X. Differential expression study of circular RNAs in exosomes from serum and urine in patients with idiopathic membranous nephropathy. Arch Med Sci 2019; 15:738-753. [PMID: 31110542 PMCID: PMC6524185 DOI: 10.5114/aoms.2019.84690] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/03/2017] [Accepted: 02/15/2018] [Indexed: 12/11/2022] Open
Abstract
INTRODUCTION The aim of the study was to further explore the pathogenesis of idiopathic membranous nephropathy (IMN), gene-sequencing was used to analyze the differentially expressed circRNAs in exosomes of patients with IMN, which may lay the foundation for the research of circRNAs as a new class of exosome-based IMN diagnosis biomarkers. MATERIAL AND METHODS Ten patients with IMN and ten normal controls were recruited as experimental subjects in our study. The exosomes were extracted from the collected serum and urine. Then, pure circRNAs were extracted from the exosomes with a series of enzymatic reactions. Afterwards, the significantly differentially expressed circRNAs were chosen by the method of gene-sequencing. RESULTS Compared with normal controls, the circRNAs were reduced in the exosomes from serum of patients with IMN, which mostly originated from intron gene regions. Meanwhile, a total of 89 circRNAs were significantly differentially expressed, which were also mostly derived from intron gene regions, including 49 up-regulated and 40 down-regulated genes. However, the species were increased in the exosomes from the urine of patients with IMN compared to normal controls, and they mainly originated from exon gene regions. Simultaneously, 60 circRNAs were significantly differentially expressed, which primarily belonged to intron gene regions, including 54 up-regulated and 6 down-regulated regions. CONCLUSIONS The significant differential and specific expression of circRNAs in the exosomes from patients with IMN were observed. For example, MUC3A, which originated from chr7:100550808|100551062, could be considered a potential diagnostic biomarker of IMN. Furthermore, these figures may be used as a reference or supplement in the research of the pathogenesis of IMN.
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Affiliation(s)
- Hualin Ma
- Department of Nephrology, Shenzhen People’s Hospital, Shenzhen Key Laboratory of Kidney Disease, Second Clinical Medical College, Jinan University, Guangzhou city, Guangdong province, China
| | - Ying Xu
- Department of Hematology, Shenzhen People’s Hospital, Second Clinical Medical College, Jinan University, Shenzhen, China
| | - Rongrong Zhang
- Department of Nephrology, Shenzhen People’s Hospital, Shenzhen Key Laboratory of Kidney Disease, Second Clinical Medical College, Jinan University, Guangzhou city, Guangdong province, China
| | - Baochun Guo
- Department of Nephrology, Shenzhen People’s Hospital, Shenzhen Key Laboratory of Kidney Disease, Second Clinical Medical College, Jinan University, Guangzhou city, Guangdong province, China
| | - Shuyan Zhang
- Department of Nephrology, Shenzhen People’s Hospital, Shenzhen Key Laboratory of Kidney Disease, Second Clinical Medical College, Jinan University, Guangzhou city, Guangdong province, China
| | - Xinzhou Zhang
- Department of Nephrology, Shenzhen People’s Hospital, Shenzhen Key Laboratory of Kidney Disease, Second Clinical Medical College, Jinan University, Guangzhou city, Guangdong province, China
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Abstract
IgA nephropathy (IgAN), a common primary glomerulonephritis worldwide, is associated with a substantial risk of progression to end-stage renal failure. The disease runs a highly variable clinical course with frequent involvement of tubulointerstitial damage. A subgroup of IgAN with proximal tubular epithelial cells (PTECs) and tubulointerstitial damage often is associated with rapid progression to end-stage renal failure. Human mesangial cell-derived mediators lead to podocyte and tubulointerstitial injury via mesangial-podocytic-tubular cross-talk. Although mesangial-podocytic communication plays a pathogenic role in podocytic injury, the implication of a podocyte-PTEC cross-talk pathway in the progression of tubulointerstitial injury in IgAN should not be underscored. We review the role of mesangial-podocytic-tubular cross-talk in the progression of IgAN. We discuss how podocytopathy in IgAN promotes subsequent PTEC dysfunction and whether tubulointerstitial injury affects the propagation of podocytic injury in IgAN. A thorough understanding of the cross-talk mechanisms among mesangial cells, podocytes, and PTECs may lead to better design of potential therapeutic options for IgAN.
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Affiliation(s)
- Joseph C K Leung
- Department of Medicine, Queen Mary Hospital, University of Hong Kong, Pokfulam, Hong Kong..
| | - Kar Neng Lai
- Nephrology Center, Hong Kong Sanatorium and Hospital, Happy Valley, Hong Kong
| | - Sydney C W Tang
- Department of Medicine, Queen Mary Hospital, University of Hong Kong, Pokfulam, Hong Kong
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29
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The first identified heterozygous nonsense mutations in podocalyxin offer new perspectives on the biology of podocytopathies. Clin Sci (Lond) 2019; 133:443-447. [PMID: 30737302 DOI: 10.1042/cs20181067] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2018] [Revised: 01/30/2019] [Accepted: 01/31/2019] [Indexed: 01/17/2023]
Abstract
In the last two decades, our understanding of the genetic underpinnings of inherited podocytopathies has advanced immensely. By sequencing the genomes of a large pool of families affected by focal segmental glomerulosclerosis (FSGS), researchers have identified a common theme: familial podocytopathies are frequently caused by genes selectively expressed in podocytes. Podocalyxin is a podocyte-specific surface sialomucin that has long been known to play important roles in podocyte morphogenesis and function. Few studies, however, have shown a conclusive link between mutations in the gene and FSGS complemented by functional evidence. In a fascinating new paper published in Clinical Science, Lin et al. identify two unrelated pedigrees in which dominant loss-of-function mutations in PODXL lead to adult-onset FSGS. Nonsense-mediated decay of the mutated PODXL transcripts leads to protein insufficiency, which in turn cause podocyte dysfunction through defects in motility and cytoskeletal organization. This is the first study to date that demonstrates, mechanistically, how autosomal dominant mutations in podocalyxin can lead to FSGS and renal insufficiency. Here, we summarize the experimental findings of this manuscript and propose, perhaps, a more controversial hypothesis: down-regulation of podocalyxin protein expression from podocytes is a critical turning point in the progression of most podocytopathies and may be mechanistically relevant to glomerulopathies in which podocyte damage is not necessarily induced by genetic lesions.
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Trimarchi H, Coppo R. Podocytopathy in the mesangial proliferative immunoglobulin A nephropathy: new insights into the mechanisms of damage and progression. Nephrol Dial Transplant 2019; 34:1280-1285. [DOI: 10.1093/ndt/gfy413] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2018] [Accepted: 12/19/2018] [Indexed: 12/25/2022] Open
Abstract
Abstract
Immunoglobulin A nephropathy (IgAN) was defined as a mesangiopathic disease, since the primary site of deposition of IgA immune material is the mesangium, and proliferation of mesangial cells and matrix excess deposition are the first histopathologic lesions. However, the relentless silent progression of IgAN is mostly due to the development of persistent proteinuria, and recent studies indicate that a major role is played by previous damage of function and anatomy of podocytes. In IgAN, the podocytopathic changes are the consequence of initial alterations in the mesangial area with accumulation of IgA containing immune material. Podocytes are therefore affected by interactions of messages originally driven from the mesangium. After continuous insult, podocytes detach from the glomerular basement membrane. This podocytopathy favours not only the development of glomerular focal and segmental sclerosis, but also the progressive renal function loss. It is still debated whether these lesions can be prevented or cured by corticosteroid/immunosuppressive treatment. We aimed to review recent data on the mechanisms implicated in the podocytopathy present in IgAN, showing new molecular risk factors for progression of this disease. Moreover, these observations may indicate that the target for new drugs is not only focused on decreasing the activity of mesangial cells and inflammatory reactions in IgAN, but also on improving podocyte function and survival.
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Affiliation(s)
- Hernán Trimarchi
- Nephrology Service, Hospital Británico de Buenos Aires, Buenos Aires, Argentina
| | - Rosanna Coppo
- Fondazione Ricerca Molinette, Regina Margherita Hospital, Turin, Italy
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31
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Kimura M, Toyoda M, Saito N, Kaneyama N, Miyatake H, Tanaka E, Komaba H, Hara M, Fukagawa M. A Liquid-Based Cytology System, without the Use of Cytocentrifugation, for Detection of Podocytes in Urine Samples of Patients with Diabetic Nephropathy. J Diabetes Res 2019; 2019:9475637. [PMID: 30911554 PMCID: PMC6398024 DOI: 10.1155/2019/9475637] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/02/2018] [Revised: 12/03/2018] [Accepted: 12/25/2018] [Indexed: 12/30/2022] Open
Abstract
OBJECTIVE Podocytes have highly differentiated functions and are extremely difficult to grow; thus, damage of podocytes is associated with glomerular dysfunction. Desquamated podocytes can be detected in urine of patients with severe renal impairment. Unlike the rapidly progressive glomerular damage in glomerulonephritis, only a few desquamated podocytes are usually detected in diabetic nephropathy (DN). It is not clear whether the low podocyte count in DN is due to limitation of the conventional method or true pathological feature. The aim of this study was to compare the conventional method with a newly modified method in detecting podocytes in morning urine samples of patients with DN. MATERIALS AND METHODS The study subjects were patients with type 2 diabetes. Urine samples from these patients were analyzed by the conventional method (Cytospin®) and the modified method (SurePath™). We determined the rate of detection of urinary podocytes and the number of detected cells. RESULTS The detection rate and podocyte count were significantly higher by the modified method than by the conventional method. The differences in the detection rates and numbers of podocytes were not significant between patients with normoalbuminuria and those with macroalbuminuria. However, they were significant in patients with microalbuminuria. The number of podocytes in the urine correlated significantly with the albumin-to-creatinine ratio, but not with the estimated glomerular filtration rate. CONCLUSIONS The true number of urinary podocytes, as measured by the modified SurePath™-based method, in patients with DN is much higher than that estimated by the conventional method.
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Affiliation(s)
- Moritsugu Kimura
- Division of Nephrology, Endocrinology and Metabolism, Department of Internal Medicine, Tokai University School of Medicine, Isehara, Japan
| | - Masao Toyoda
- Division of Nephrology, Endocrinology and Metabolism, Department of Internal Medicine, Tokai University School of Medicine, Isehara, Japan
| | - Nobumichi Saito
- Division of Nephrology, Endocrinology and Metabolism, Department of Internal Medicine, Tokai University School of Medicine, Isehara, Japan
| | - Noriko Kaneyama
- Division of Nephrology, Endocrinology and Metabolism, Department of Internal Medicine, Tokai University School of Medicine, Isehara, Japan
| | - Han Miyatake
- Division of Nephrology, Endocrinology and Metabolism, Department of Internal Medicine, Tokai University School of Medicine, Isehara, Japan
| | - Eitaro Tanaka
- Division of Nephrology, Endocrinology and Metabolism, Department of Internal Medicine, Tokai University School of Medicine, Isehara, Japan
| | - Hirotaka Komaba
- Division of Nephrology, Endocrinology and Metabolism, Department of Internal Medicine, Tokai University School of Medicine, Isehara, Japan
| | | | - Masafumi Fukagawa
- Division of Nephrology, Endocrinology and Metabolism, Department of Internal Medicine, Tokai University School of Medicine, Isehara, Japan
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32
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Horikawa A, Yoneda T, Yaoita E, Yamaguchi K, Shigenobu S, Kuramochi M, Yamate J, Inui T, Ishibashi O. A novel splicing variant of small nucleolar RNA host gene 4 is a podocyte-selective non-coding RNA upregulated in response to puromycin aminonucleoside-induced podocyte injury. J Biochem 2018; 165:447-454. [DOI: 10.1093/jb/mvy118] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2018] [Accepted: 12/13/2018] [Indexed: 12/14/2022] Open
Affiliation(s)
- Aya Horikawa
- Department of Applied Life Sciences, Osaka Prefecture University, Graduate School of Life and Environmental Sciences, 1-1 Gakuen-cho, Naka-ku, Sakai, Osaka, Japan
| | - Tomomi Yoneda
- Department of Applied Life Sciences, Osaka Prefecture University, Graduate School of Life and Environmental Sciences, 1-1 Gakuen-cho, Naka-ku, Sakai, Osaka, Japan
| | - Eishin Yaoita
- Department of Structural Pathology, Kidney Research Center, Niigata University Graduate School of Medical and Dental Sciences, 1-757 Asahimachi-dori, Chuo-ku, Niigata, Japan
| | - Katsushi Yamaguchi
- NIBB Core Research Facilities, National Institute for Basic Biology, 38 Nishigonaka, Myodaiji, Okazaki, Japan
| | - Shuji Shigenobu
- NIBB Core Research Facilities, National Institute for Basic Biology, 38 Nishigonaka, Myodaiji, Okazaki, Japan
| | - Mizuki Kuramochi
- Laboratory of Veterinary Pathology, Graduate School of Life and Environmental Sciences, Osaka Prefecture University, 1-58 Rinku-Ourai-Kita, Izumisano, Osaka, Japan
| | - Jyoji Yamate
- Laboratory of Veterinary Pathology, Graduate School of Life and Environmental Sciences, Osaka Prefecture University, 1-58 Rinku-Ourai-Kita, Izumisano, Osaka, Japan
| | - Takashi Inui
- Department of Applied Life Sciences, Osaka Prefecture University, Graduate School of Life and Environmental Sciences, 1-1 Gakuen-cho, Naka-ku, Sakai, Osaka, Japan
| | - Osamu Ishibashi
- Department of Applied Life Sciences, Osaka Prefecture University, Graduate School of Life and Environmental Sciences, 1-1 Gakuen-cho, Naka-ku, Sakai, Osaka, Japan
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Yuan YP, Zhao H, Peng LQ, Li ZF, Liu S, Yuan CY, Mwamunyi MJ, Pearce D, Yao LJ. The SGK3-triggered ubiquitin-proteasome degradation of podocalyxin (PC) and ezrin in podocytes was associated with the stability of the PC/ezrin complex. Cell Death Dis 2018; 9:1114. [PMID: 30385740 PMCID: PMC6212497 DOI: 10.1038/s41419-018-1161-1] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2018] [Revised: 09/27/2018] [Accepted: 10/18/2018] [Indexed: 12/28/2022]
Abstract
Podocyte damage is commonly accompanied by destabilization of the podocalyxin (PC)/ezrin complex. Serum- and glucocorticoid-inducible kinase 3 (SGK3) plays a role in the maintenance of podocyte function, but the details of this role are poorly understood. Herein we demonstrated that SGK3 and its downstream target protein neural precursor cell expressed developmentally downregulated protein 4 subtype 2 (Nedd4-2) triggered PC and ezrin interaction. In adriamycin (ADR)-induced nephritic mice, and after puromycin aminonucleoside (PAN)-induced podocyte damage in vitro, PC and ezrin protein expression levels decreased significantly, while Nedd4-2 activity increased. Moreover, PAN treatment increased PC and ezrin ubiquitination and decreased PC/ezrin interaction in cultured mouse podocytes. The downregulation of SGK3 activity in mouse podocytes resulted in decreased PC and ezrin protein expression and increased the ubiquitin-proteasome degradation of PC and ezrin. Furthermore, upregulation of SGK3 activity mostly reversed the PAN-induced decrease in PC and ezrin protein expression. Overexpression of Nedd4-2 led to decreased ezrin protein expression via the upregulation of ezrin ubiquitination. In contrast, Nedd4-2 knockdown resulted in increased ezrin protein expression but decreased ezrin ubiquitination. In PC-transfected human embryonic kidney (HEK293T) cells, SGK3 activity downregulation and Nedd4-2 overexpression resulted in decreased PC/ezrin interaction. These results suggested that SGK3 triggers the ubiquitin-proteasome degradation of PC and ezrin, while the SGK3/Nedd4-2 signaling pathway regulates ezrin, but not PC, ubiquitination. Thus SGK3 helps to regulate podocyte function by maintaining the stability of the PC/ezrin complex.
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Affiliation(s)
- Ya-Pei Yuan
- Department of Nephrology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, 430022, Wuhan, China
| | - Hong Zhao
- Department of Trauma Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, 430030, Wuhan, China
| | - Li-Qin Peng
- Department of Nephrology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, 430022, Wuhan, China.,Department of Rheumatology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, 510120, Guangzhou, China
| | - Zi-Fang Li
- Department of Nephrology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, 430022, Wuhan, China
| | - Song Liu
- Department of Nephrology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, 430022, Wuhan, China
| | - Cheng-Yan Yuan
- Department of Nephrology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, 430022, Wuhan, China
| | - Mercy-Julian Mwamunyi
- Department of Nephrology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, 430022, Wuhan, China
| | - David Pearce
- Department of Medicine, University of California, San Francisco, CA, 94107-2140, USA.,Department of Molecular and Cellular Pharmacology, University of California, San Francisco, CA, 94107-2140, USA
| | - Li-Jun Yao
- Department of Nephrology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, 430022, Wuhan, China.
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Akankwasa G, Jianhua L, Guixue C, Changjuan A, Xiaosong Q. Urine markers of podocyte dysfunction: a review of podocalyxin and nephrin in selected glomerular diseases. Biomark Med 2018; 12:927-935. [PMID: 29976076 DOI: 10.2217/bmm-2018-0152] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Urinary podocalyxin and nephrin are urine markers of podocyte dysfunction that may reflect the integrity of kidney's filtration barrier. Studies on their respective roles in glomerular diseases are still underway. However, the isolated and unsystematic manner in which they are being studied does not permit proper identification of their roles in each glomerular disease. As such, there is little or no appreciation of what research has already achieved and what remains to be achieved as the research direction is not clearly defined. We explored the recent studies and outlined the major findings regarding the value of both biomarkers in each of the three glomerular disease entities. Our review covered diabetic nephropathy, membranous nephropathy and IgA nephropathy.
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Affiliation(s)
- Gilbert Akankwasa
- Department of Laboratory Medicine, Shengjing Hospital of China Medical University, No. 36 Sanhao Street, Heping District Shenyang, Liaoning 110004, PR China
| | - Liu Jianhua
- Department of Laboratory Medicine, Shengjing Hospital of China Medical University, No. 36 Sanhao Street, Heping District Shenyang, Liaoning 110004, PR China
| | - Cheng Guixue
- Department of Laboratory Medicine, Shengjing Hospital of China Medical University, No. 36 Sanhao Street, Heping District Shenyang, Liaoning 110004, PR China
| | - An Changjuan
- Department of Laboratory Medicine, Shengjing Hospital of China Medical University, No. 36 Sanhao Street, Heping District Shenyang, Liaoning 110004, PR China
| | - Qin Xiaosong
- Department of Laboratory Medicine, Shengjing Hospital of China Medical University, No. 36 Sanhao Street, Heping District Shenyang, Liaoning 110004, PR China
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35
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Ikuma D, Hiromura K, Kajiyama H, Suwa J, Ikeuchi H, Sakairi T, Kaneko Y, Maeshima A, Kurosawa H, Hirayama Y, Yokota K, Araki Y, Sato K, Asanuma YF, Akiyama Y, Hara M, Nojima Y, Mimura T. The correlation of urinary podocytes and podocalyxin with histological features of lupus nephritis. Lupus 2017; 27:484-493. [PMID: 29050536 DOI: 10.1177/0961203317734918] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Objectives The objective of this study was to test the correlation of urinary podocyte number (U-Pod) and urinary podocalyxin levels (U-PCX) with histology of lupus nephritis. Methods This was an observational, cross-sectional study. Sixty-four patients were enrolled: 40 with lupus nephritis and 24 without lupus nephritis (12 lupus nephritis patients in complete remission and 12 systemic lupus erythematosus patients without lupus nephritis). Urine samples were collected before initiating treatment. U-Pod was determined by counting podocalyxin-positive cells, and U-PCX was measured by sandwich ELISA, normalized to urinary creatinine levels (U-Pod/Cr, U-PCX/Cr). Results Lupus nephritis patients showed significantly higher U-Pod/Cr and U-PCX/Cr compared with patients without lupus nephritis. U-Pod/Cr was high in proliferative lupus nephritis (class III±V/IV±V), especially in pure class IV (4.57 (2.02-16.75)), but low in pure class V (0.30 (0.00-0.71)). U-Pod/Cr showed a positive correlation with activity index ( r=0.50, P=0.0012) and was independently associated with cellular crescent formation. In contrast, U-PCX/Cr was high in both proliferative and membranous lupus nephritis. Receiver operating characteristic analysis revealed significant correlation of U-Pod/Cr with pure class IV, class IV±V and cellular crescent formation, and the combined values of U-Pod/Cr and U-PCX/Cr were shown to be associated with pure class V. Conclusions U-Pod/Cr and U-PCX/Cr correlate with histological features of lupus nephritis.
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Affiliation(s)
- D Ikuma
- 1 Department of Rheumatology and Applied Immunology, Saitama Medical University, Saitama, Japan
| | - K Hiromura
- 2 Department of Medicine and Clinical Science, Gunma University Graduate School of Medicine, Gunma, Japan
| | - H Kajiyama
- 1 Department of Rheumatology and Applied Immunology, Saitama Medical University, Saitama, Japan
| | - J Suwa
- 2 Department of Medicine and Clinical Science, Gunma University Graduate School of Medicine, Gunma, Japan
| | - H Ikeuchi
- 2 Department of Medicine and Clinical Science, Gunma University Graduate School of Medicine, Gunma, Japan
| | - T Sakairi
- 2 Department of Medicine and Clinical Science, Gunma University Graduate School of Medicine, Gunma, Japan
| | - Y Kaneko
- 2 Department of Medicine and Clinical Science, Gunma University Graduate School of Medicine, Gunma, Japan
| | - A Maeshima
- 2 Department of Medicine and Clinical Science, Gunma University Graduate School of Medicine, Gunma, Japan
| | - H Kurosawa
- 3 Diagnostics Research Department, Denka Innovation Center, Tokyo, Japan
| | - Y Hirayama
- 3 Diagnostics Research Department, Denka Innovation Center, Tokyo, Japan
| | - K Yokota
- 1 Department of Rheumatology and Applied Immunology, Saitama Medical University, Saitama, Japan
| | - Y Araki
- 1 Department of Rheumatology and Applied Immunology, Saitama Medical University, Saitama, Japan
| | - K Sato
- 1 Department of Rheumatology and Applied Immunology, Saitama Medical University, Saitama, Japan
| | - Y F Asanuma
- 1 Department of Rheumatology and Applied Immunology, Saitama Medical University, Saitama, Japan
| | - Y Akiyama
- 1 Department of Rheumatology and Applied Immunology, Saitama Medical University, Saitama, Japan.,4 Department of Rheumatology, Japanese Red Cross Ogawa Hospital, Saitama, Japan
| | - M Hara
- 5 Department of Pediatrics, Yoshida Hospital, Niigata, Japan
| | - Y Nojima
- 6 Department of Nephrology, Japanese Red Cross Maebashi Hospital, Gunma, Japan
| | - T Mimura
- 1 Department of Rheumatology and Applied Immunology, Saitama Medical University, Saitama, Japan
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36
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Krochmal M, Cisek K, Filip S, Markoska K, Orange C, Zoidakis J, Gakiopoulou C, Spasovski G, Mischak H, Delles C, Vlahou A, Jankowski J. Identification of novel molecular signatures of IgA nephropathy through an integrative -omics analysis. Sci Rep 2017; 7:9091. [PMID: 28831120 PMCID: PMC5567309 DOI: 10.1038/s41598-017-09393-w] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2017] [Accepted: 07/26/2017] [Indexed: 12/19/2022] Open
Abstract
IgA nephropathy (IgAN) is the most prevalent among primary glomerular diseases worldwide. Although our understanding of IgAN has advanced significantly, its underlying biology and potential drug targets are still unexplored. We investigated a combinatorial approach for the analysis of IgAN-relevant -omics data, aiming at identification of novel molecular signatures of the disease. Nine published urinary proteomics datasets were collected and the reported differentially expressed proteins in IgAN vs. healthy controls were integrated into known biological pathways. Proteins participating in these pathways were subjected to multi-step assessment, including investigation of IgAN transcriptomics datasets (Nephroseq database), their reported protein-protein interactions (STRING database), kidney tissue expression (Human Protein Atlas) and literature mining. Through this process, from an initial dataset of 232 proteins significantly associated with IgAN, 20 pathways were predicted, yielding 657 proteins for further analysis. Step-wise evaluation highlighted 20 proteins of possibly high relevance to IgAN and/or kidney disease. Experimental validation of 3 predicted relevant proteins, adenylyl cyclase-associated protein 1 (CAP1), SHC-transforming protein 1 (SHC1) and prolylcarboxypeptidase (PRCP) was performed by immunostaining of human kidney sections. Collectively, this study presents an integrative procedure for -omics data exploitation, giving rise to biologically relevant results.
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Affiliation(s)
- Magdalena Krochmal
- Biomedical Research Foundation Academy of Athens, Center of Basic Research, Athens, Greece
- RWTH Aachen University Hospital, Institute for Molecular Cardiovascular Research, Aachen, Germany
| | | | - Szymon Filip
- Biomedical Research Foundation Academy of Athens, Center of Basic Research, Athens, Greece
| | - Katerina Markoska
- Department of Nephrology, Medical Faculty, University of Skopje, Skopje, Macedonia
| | - Clare Orange
- Department of Pathology, School of Medicine, University of Glasgow, Glasgow, UK
| | - Jerome Zoidakis
- Biomedical Research Foundation Academy of Athens, Center of Basic Research, Athens, Greece
| | - Chara Gakiopoulou
- Pathology Department, National and Kapodistrian University of Athens, Athens, Greece
| | - Goce Spasovski
- Department of Nephrology, Medical Faculty, University of Skopje, Skopje, Macedonia
| | - Harald Mischak
- Mosaiques Diagnostics GmbH, Hannover, Germany
- University of Glasgow, Institute of Cardiovascular and Medical Sciences, Glasgow, UK
| | - Christian Delles
- Institute of Cardiovascular and Medical Sciences, BHF Glasgow Cardiovascular Research Centre, University of Glasgow, 126 University Place, Glasgow, G12 8TA, UK
| | - Antonia Vlahou
- Biomedical Research Foundation Academy of Athens, Center of Basic Research, Athens, Greece.
| | - Joachim Jankowski
- RWTH Aachen University Hospital, Institute for Molecular Cardiovascular Research, Aachen, Germany.
- University of Maastricht, CARIM School for Cardiovascular Diseases, Maastricht, Netherlands.
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In Acute IgA Nephropathy, Proteinuria and Creatinine Are in the Spot, but Podocyturia Operates in Silence: Any Place for Amiloride? Case Rep Nephrol 2017; 2017:1292531. [PMID: 28473934 PMCID: PMC5394405 DOI: 10.1155/2017/1292531] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2017] [Revised: 02/27/2017] [Accepted: 03/02/2017] [Indexed: 11/26/2022] Open
Abstract
IgA nephropathy is the most frequent cause of primary glomerulonephritis, portends erratic patterns of clinical presentation, and lacks specific treatment. In general, it slowly progresses to end-stage renal disease. The clinical course and the response to therapy are usually assessed with proteinuria and serum creatinine. Validated biomarkers have not been identified yet. In this report, we present a case of acute renal injury with proteinuria and microscopic hematuria in a young male. A kidney biopsy disclosed IgA nephropathy. Podocyturia was significantly elevated compared to normal subjects. Proteinuria, renal function, and podocyturia improved promptly after steroids and these variables remained normal after one year of follow-up, when steroids had already been discontinued and patient continued on valsartan and amiloride. Our report demonstrates that podocyturia is critically elevated during an acute episode of IgA nephropathy, and its occurrence may explain the grim long-term prognosis of this entity. Whether podocyturia could be employed in IgA nephropathy as a trustable biomarker for treatment assessment or even for early diagnosis of IgA nephropathy relapses should be further investigated.
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Fall B, Scott CR, Mauer M, Shankland S, Pippin J, Jefferson JA, Wallace E, Warnock D, Najafian B. Urinary Podocyte Loss Is Increased in Patients with Fabry Disease and Correlates with Clinical Severity of Fabry Nephropathy. PLoS One 2016; 11:e0168346. [PMID: 27992580 PMCID: PMC5161377 DOI: 10.1371/journal.pone.0168346] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2016] [Accepted: 11/29/2016] [Indexed: 11/18/2022] Open
Abstract
Chronic kidney disease is a major complication of Fabry disease. Podocytes accumulate globotriaosylceramide inclusions more than other kidney cell types in Fabry patients. Podocyte injury occurs early in age, and is progressive. Since injured podocytes detach into the urine (podocyturia), we hypothesized that podocyturia would increase in Fabry patients and correlate with clinical severity of Fabry nephropathy. Urine specimens from 39 Fabry patients and 24 healthy subjects were evaluated for podocyturia. Most of the Fabry patients and many healthy subjects had podocyturia. The number of podocytes per gram of urine creatinine (UPodo/g Cr) was 3.6 fold greater in Fabry patients (3,741 ± 2796; p = 0.001) than healthy subjects (1,040 ± 972). Fabry patients with normoalbuminuria and normoproteinuria had over 2-fold greater UPodo/g Cr than healthy subjects (p = 0.048). UPodo/gCr was inversely related to eGFR in male patients (r = -0.69, p = 0.003). UPodo/gCr was directly related to urine protein creatinine ratio (r = 0.33; p = 0.04) in all Fabry patients. These studies confirm increased podocyturia in Fabry disease, even when proteinuria and albuminuria are absent. Podocyturia correlates with clinical severity of Fabry nephropathy, and potentially may be of prognostic value.
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Affiliation(s)
- Brent Fall
- Department of Pathology, University of Washington, Seattle, United States America
| | - C Ronald Scott
- Department of Pediatrics, University of Washington, Seattle, United States America
| | - Michael Mauer
- Departments of Pediatrics, University of Minnesota, Minneapolis, United States America.,Departments of Medicine, University of Minnesota, Minneapolis, United States America
| | - Stuart Shankland
- Department of Medicine, University of Washington, Seattle, United States America
| | - Jeffrey Pippin
- Department of Medicine, University of Washington, Seattle, United States America
| | - Jonathan A Jefferson
- Department of Medicine, University of Washington, Seattle, United States America
| | - Eric Wallace
- Department of Medicine, University of Alabama, Birmingham, United States America
| | - David Warnock
- Department of Medicine, University of Alabama, Birmingham, United States America
| | - Behzad Najafian
- Department of Pathology, University of Washington, Seattle, United States America
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Imaizumi T, Nakatochi M, Akiyama S, Yamaguchi M, Kurosawa H, Hirayama Y, Katsuno T, Tsuboi N, Hara M, Maruyama S. Urinary Podocalyxin as a Biomarker to Diagnose Membranous Nephropathy. PLoS One 2016; 11:e0163507. [PMID: 27668430 PMCID: PMC5036798 DOI: 10.1371/journal.pone.0163507] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2016] [Accepted: 09/09/2016] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND A non-invasive diagnostic marker of membranous nephropathy (MN) is desirable. The urinary level of podocalyxin (PCX) is higher in various glomerular diseases, including MN. The aim of this study was to construct a diagnostic model of MN with the combination of urinary PCX and clinical parameters. METHODS We performed this cross-sectional study to construct the diagnostic models for MN by using data and samples from the multicenter kidney biopsy registry of Nagoya University and its affiliated hospitals. Urinary (u-) PCX was measured by sandwich ELISA. We constructed 3 types of diagnostic models in 105 training samples: u-PCX univariate model, the combined model of clinical parameters other than u-PCX (clinical model), and the combined model of both u-PCX and clinical parameters (combined model). We assessed the clinical usefulness of the diagnostic models through the comparison of c-statistics and decision curve analysis (DCA) in 209 validation samples. RESULTS The clinical model consisted of age, glomerular filtration rate, and diabetes mellitus. In the training cohort, the c-statistics were 0.868 [95% CI, 0.799-0.937] in the combined model. In the validation cohort, sensitivity was 80.5% and specificity was 73.5% on the cut-off value. The net benefit of the combined model was better between threshold probabilities of 40-80% in DCA. CONCLUSIONS In this study, we demonstrated the utility of u-PCX as a diagnostic marker for MN and the clinical usefulness of the diagnostic models, through the combination of u-PCX and clinical parameters including age, glomerular filtration rate, and diabetes mellitus.
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Affiliation(s)
- Takahiro Imaizumi
- Department of Nephrology, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Masahiro Nakatochi
- Biostatistics and Bioinformatics Section, Center for Advanced Medicine and Clinical Research, Nagoya University Hospital, Nagoya, Japan
| | - Shin’ichi Akiyama
- Department of Nephrology, Nagoya University Graduate School of Medicine, Nagoya, Japan
- * E-mail:
| | - Makoto Yamaguchi
- Department of Nephrology, Yokkaichi Municipal Hospital, Yokkaichi, Japan
| | | | | | - Takayuki Katsuno
- Department of Nephrology, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Naotake Tsuboi
- Department of Nephrology, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Masanori Hara
- Department of Pediatrics, Niigata prefecture Yoshida hospital, Tsubame, Japan
| | - Shoichi Maruyama
- Department of Nephrology, Nagoya University Graduate School of Medicine, Nagoya, Japan
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Tomino Y. Diagnosis and treatment of patients with IgA nephropathy in Japan. Kidney Res Clin Pract 2016; 35:197-203. [PMID: 27957413 PMCID: PMC5142264 DOI: 10.1016/j.krcp.2016.09.001] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2016] [Revised: 08/25/2016] [Accepted: 09/02/2016] [Indexed: 01/27/2023] Open
Abstract
Chronic kidney disease (CKD) is a worldwide public health problem that affects millions of people from all racial and ethnic groups. Although CKD is not one specific disease, it is a comprehensive syndrome that includes IgA nephropathy. As reported by the Japanese Society of Nephrology, 13.0 million people have CKD. In Japan, major causes of end-stage kidney disease are type 2 diabetic nephropathy, chronic glomerulonephritis, especially IgA nephropathy, hypertensive nephrosclerosis, and polycystic kidney disease. IgA nephropathy is characterized by polymeric IgA1 with aberrant galactosylation (galactose-deficient IgA1) increased in the blood and deposited in the glomerular mesangial areas, as well as partially in the capillary walls. The tonsils are important as one of the responsible regions in this disease. The clarification of the mechanism of galactose-deficient IgA1 production will pave the way for the development of novel therapies. The results of future research are eagerly awaited. At present, the most important therapeutic goals in patients with IgA nephropathy are the control of hypertension, the decrease of urinary protein excretion, and the inhibition of progression to end-stage kidney disease. Several investigators have reported that renin-angiotensin-aldosterone system inhibitors reduce levels of urinary protein excretion and preserve renal function in patients with IgA nephropathy. In Japan, tonsillectomy and steroid pulse therapy are more effective for patients with IgA nephropathy.
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Affiliation(s)
- Yasuhiko Tomino
- Juntendo University, Tokyo, Japan; Medical Corporation SHOWAKAI, Tokyo, Japan
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41
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Abstract
We have summarized the latest findings on markers for progression of immunoglobulin A (IgA) nephropathy (IgAN), the most common primary glomerulonephritis with a high prevalence among end-stage renal disease (ESRD) patients. The clinical predictors of renal outcome in IgAN nephropathy, such as proteinuria, hypertension, and decreased estimated glomerular filtration rate (eGFR) at the time of the diagnosis, are well known. The Oxford classification of IgAN identified four types of histological lesions (known as the MEST score) associated with the development of ESRD and/or a 50 % reduction in eGFR. In addition, the role of genetic risk factors associated with IgAN is being elucidated by genome-wide association studies, with multiple risk alleles described. Recently, biomarkers in serum (galactose-deficient IgA1, IgA/IgG autoantibodies against galactose-deficient IgA1, and soluble CD 89-IgA complexes) and urine (soluble transferrin receptor, interleukin-6/epidermal growth factor ratio, fractalkine, laminin G-like 3 peptide, κ light chains, and mannan-binding lectin) have been identified. Some of these biomarkers may represent candidates for the development of noninvasive diagnostic tests, that would be useful for detection of subclinical disease activity, monitoring disease progression, assessment of treatment, and at the same time circumventing the complications associated with renal biopsies. These advances, along with future disease-specific therapy, will be helpful in improving the treatment effectiveness, prognosis, and the quality of life in connection with IgAN.
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Abstract
Globally, IgA nephropathy (IgAN) is the most common primary glomerulonephritis that can progress to renal failure. The exact pathogenesis of IgAN is not well defined, but current biochemical and genetic data implicate overproduction of aberrantly glycosylated IgA1. These aberrant immunoglobulins are characterized by galactose deficiency of some hinge-region O-linked glycans. However, aberrant glycosylation alone is insufficient to induce renal injury: the participation of glycan-specific IgA and IgG autoantibodies that recognize the undergalactosylated IgA1 molecule is required. Glomerular deposits of immune complexes containing undergalactosylated IgA1 activate mesangial cells, leading to the local overproduction of cytokines, chemokines and complement. Emerging data indicate that mesangial-derived mediators that are released following mesangial deposition of IgA1 lead to podocyte and tubulointerstitial injury via humoral crosstalk. Patients can present with a range of signs and symptoms, from asymptomatic microscopic haematuria to macroscopic haematuria. The clinical progression varies, with 30-40% of patients reaching end-stage renal disease 20-30 years after the first clinical presentation. Currently, no IgAN-specific therapies are available and patients are managed with the aim of controlling blood pressure and maintaining renal function. However, new therapeutic approaches are being developed, building upon our ever-improving understanding of disease pathogenesis.
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Shoji M, Kobayashi K, Takemoto M, Sato Y, Yokote K. Urinary podocalyxin levels were associated with urinary albumin levels among patients with diabetes. Biomarkers 2015; 21:164-7. [PMID: 26635084 DOI: 10.3109/1354750x.2015.1118551] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Diabetic nephropathy has dramatically increased worldwide. In this study, we measured urinary podocalyxin in 240 patients with diabetes. The relationship between urinary podocalyxin and clinical parameters and the effects of dipeptidyl peptidase-4 inhibitors (DPP4i) and alpha-glucosidase inhibitor (a-GI) on urinary podocalyxin levels were examined. Urinary podocalyxin levels were significantly higher in patients with microalbuminuria than in those with normoalbuminuria. Urinary podocalyxin levels were also significantly related to albumin-to-creatinine ratio. Neither DPP4i nor α-GI ameliorated the increase in urinary podocalyxin levels. Our results indicated that urinary podocalyxin will be not only an early marker but also a treatment target for DN.
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Affiliation(s)
- M Shoji
- a Department of Clinical Cell Biology and Medicine , Chiba University Graduate School of Medicine , Chiba , Japan .,b Department of Medicine , Division of Diabetes, Metabolism and Endocrinology, Chiba University Hospital , Chiba , Japan , and
| | - K Kobayashi
- a Department of Clinical Cell Biology and Medicine , Chiba University Graduate School of Medicine , Chiba , Japan .,b Department of Medicine , Division of Diabetes, Metabolism and Endocrinology, Chiba University Hospital , Chiba , Japan , and
| | - M Takemoto
- a Department of Clinical Cell Biology and Medicine , Chiba University Graduate School of Medicine , Chiba , Japan .,b Department of Medicine , Division of Diabetes, Metabolism and Endocrinology, Chiba University Hospital , Chiba , Japan , and
| | - Y Sato
- c Clinical Research Center, Chiba University Hospital , Chiba , Japan
| | - K Yokote
- a Department of Clinical Cell Biology and Medicine , Chiba University Graduate School of Medicine , Chiba , Japan .,b Department of Medicine , Division of Diabetes, Metabolism and Endocrinology, Chiba University Hospital , Chiba , Japan , and
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Wang Y, Gu Y, Loyd S, Jia X, Groome LJ. Increased urinary levels of podocyte glycoproteins, matrix metallopeptidases, inflammatory cytokines, and kidney injury biomarkers in women with preeclampsia. Am J Physiol Renal Physiol 2015; 309:F1009-17. [PMID: 26671966 DOI: 10.1152/ajprenal.00257.2015] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2015] [Accepted: 10/13/2015] [Indexed: 12/21/2022] Open
Abstract
To investigate kidney injury in preeclampsia, we analyzed 14 biomarkers in urine specimen from 4 groups of pregnant women (normotensive pregnant women and those with pregnancy complicated with chronic hypertension or mild or severe preeclampsia). These biomarkers included 1) podocyte glycoproteins nephrin and podocalyxin, 2) matrix metallopeptidase (MMP)-2 and MMP-9 and their inhibitor tissue inhibitor of metalloproteinase-2, 3) inflammatory molecules and cytokines soluble VCAM-1, TNF-α, soluble TNF receptor receptor-1, IL-6, IL-8, IL-10, and IL-18, and 4) kidney injury biomarkers neutrophil gelatinase-associated lipocalin and kidney injury molecule-1. Postpartum urine specimens (6-8 wk) from normotensive women and those with severe preeclampsia were also evaluated. We found that, first, urine levels of nephrin, MMP-2, MMP-9, and kidney injury molecule-1 were significantly higher before delivery in severe preeclampsia than normotensive groups. The increased levels were all reduced to levels similar to those of the normotensive control group in postpartum specimens from the severe preeclampsia group. Second, soluble VCAM-1, soluble TNF receptor-1, and neutrophil gelatinase-associated lipocalin levels were significantly increased in the severe preeclampsia group compared with the normotensive control group before delivery, but levels of these molecules were significantly reduced in postpartum specimens in both groups. Third, IL-6 and IL-8 levels were not different between preeclampsia and normotensive groups but significantly increased in pregnancy complicated with chronic hypertension. Finally, tissue inhibitor of metalloproteinase-2 and IL-18 levels were not different among the study groups before delivery but were significantly reduced in postpartum specimens from normotensive controls. Our results indicate that the kidney experiences an increased inflammatory response during pregnancy. Most interestingly, tubular epithelial cell injury may also occur in severe preeclampsia. These biomarkers could be used to assess podocyte or tubular injury and kidney inflammatory responses during pregnancy and to evaluate postpartum kidney injury recovery in pregnancy-complicated disorders.
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Affiliation(s)
- Yuping Wang
- Department of Obstetrics and Gynecology, Louisiana State University Health Sciences Center, Shreveport, Louisiana; and Department of Molecular and Cellular Physiology, Louisiana State University Health Sciences Center, Shreveport, Louisiana
| | - Yang Gu
- Department of Obstetrics and Gynecology, Louisiana State University Health Sciences Center, Shreveport, Louisiana; and
| | - Susan Loyd
- Department of Obstetrics and Gynecology, Louisiana State University Health Sciences Center, Shreveport, Louisiana; and
| | - Xiuyue Jia
- Department of Obstetrics and Gynecology, Louisiana State University Health Sciences Center, Shreveport, Louisiana; and
| | - Lynn J Groome
- Department of Obstetrics and Gynecology, Louisiana State University Health Sciences Center, Shreveport, Louisiana; and
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Moresco RN, Speeckaert MM, Delanghe JR. Diagnosis and monitoring of IgA nephropathy: the role of biomarkers as an alternative to renal biopsy. Autoimmun Rev 2015; 14:847-53. [PMID: 26026694 DOI: 10.1016/j.autrev.2015.05.009] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2015] [Accepted: 05/20/2015] [Indexed: 12/13/2022]
Abstract
IgA nephropathy (IgAN) is the most prevalent form of chronic glomerulonephritis in the world. The underlying pathogenesis of this autoimmune disease comprises the formation of immune complexes, including glycan-specific IgA1 or IgG antibodies and an aberrant glycosylation of IgA1. Until now, anatomopathological analysis of renal biopsies is essential for the diagnosis of IgAN and different histological classification systems have been proposed, e.g. the Oxford classification. However, a percutaneous renal biopsy is frequently not performed for several reasons and the Oxford classification system has some limitations. Since the poor prognosis of IgAN patients is partly the result of a delayed diagnosis, there is an urgent need for reliable noninvasive biomarkers that might be applicable in routine clinical practice. This article reviews the advances on the understanding of the underlying pathophysiological mechanisms of IgAN and discusses in depth the recent development of new biomarkers, including the use of proteomics and microRNAs.
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Affiliation(s)
- Rafael N Moresco
- Department of Clinical Chemistry, Ghent University Hospital, Gent, Belgium; Department of Clinical and Toxicological Analysis, Federal University of Santa Maria, Santa Maria, Brazil
| | | | - Joris R Delanghe
- Department of Clinical Chemistry, Ghent University Hospital, Gent, Belgium.
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Fukuda A, Sato Y, Iwakiri T, Komatsu H, Kikuchi M, Kitamura K, Wiggins RC, Fujimoto S. Urine podocyte mRNAs mark disease activity in IgA nephropathy. Nephrol Dial Transplant 2015; 30:1140-50. [PMID: 25956757 DOI: 10.1093/ndt/gfv104] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2014] [Accepted: 03/21/2015] [Indexed: 01/18/2023] Open
Abstract
BACKGROUND Podocyte depletion is a major mechanism driving glomerulosclerosis. We and others have previously projected from model systems that podocyte-specific mRNAs in the urine pellet might serve as glomerular disease markers. We evaluated IgA nephropathy (IgAN) to test this concept. METHODS From 2009 to 2013, early morning voided urine samples and kidney biopsies from IgAN patients (n = 67) were evaluated in comparison with urine samples from healthy age-matched volunteers (n = 28). Urine podocyte (podocin) mRNA expressed in relation to either urine creatinine concentration or a kidney tubular marker (aquaporin 2) was tested as markers. RESULTS Urine podocyte mRNAs were correlated with the severity of active glomerular lesions (segmental glomerulosclerosis and acute extracapillary proliferation), but not with non-glomerular lesions (tubular atrophy/interstitial fibrosis) or with clinical parameters of kidney injury (serum creatinine and estimated glomerular filtration rate), or with degree of accumulated podocyte loss at the time of biopsy. In contrast, proteinuria correlated with all histological and clinical markers. Glomerular tuft podocyte nuclear density (a measure of cumulative podocyte loss) correlated with tubular atrophy/interstitial fibrosis, estimated-glomerular filtration rate and proteinuria, but not with urine podocyte markers. In a subset of the IgA cohort (n = 19, median follow-up period = 37 months), urine podocyte mRNAs were significantly decreased after treatment, in contrast to proteinuria which was not significantly changed. CONCLUSIONS Urine podocyte mRNAs reflect active glomerular injury at a given point in time, and therefore provide both different and additional clinical information that can complement proteinuria in the IgAN decision-making paradigm.
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Affiliation(s)
- Akihiro Fukuda
- First Department of Internal Medicine, University of Miyazaki, Miyazaki, Japan
| | - Yuji Sato
- First Department of Internal Medicine, University of Miyazaki, Miyazaki, Japan
| | - Takashi Iwakiri
- First Department of Internal Medicine, University of Miyazaki, Miyazaki, Japan
| | - Hiroyuki Komatsu
- First Department of Internal Medicine, University of Miyazaki, Miyazaki, Japan
| | - Masao Kikuchi
- First Department of Internal Medicine, University of Miyazaki, Miyazaki, Japan
| | - Kazuo Kitamura
- First Department of Internal Medicine, University of Miyazaki, Miyazaki, Japan
| | - Roger C Wiggins
- Division of Nephrology, Department of Internal Medicine, University of Michigan, Ann Arbor, MI, USA
| | - Shouichi Fujimoto
- First Department of Internal Medicine, University of Miyazaki, Miyazaki, Japan Department of Hemovascular Medicine and Artificial Organs, University of Miyazaki, Miyazaki, Japan
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Sasaki Y, Shimizu Y, Suzuki Y, Horikoshi S, Tomino Y. TWEAK/Fn14 system and crescent formation in IgA nephropathy. BMC Nephrol 2015; 16:27. [PMID: 25885587 PMCID: PMC4363378 DOI: 10.1186/s12882-015-0022-8] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2014] [Accepted: 02/20/2015] [Indexed: 01/16/2023] Open
Abstract
Background The TNF-like weak inducer of apoptosis (TWEAK) contributes to kidney inflammation producing secretion by renal cells. The present study examined whether the level of TWEAK is associated with histologic findings in patients with IgA nephropathy (IgAN). Methods The levels of urinary TWEAK (uTWEAK) from 116 IgAN patients, 50 non-IgA kidney disease patients, and 50 healthy individuals were measured by ELISA. Histological findings of renal biopsy specimens of patients with IgAN were evaluated according to the Oxford classification and histological classification for IgAN in Japan. We investigated the expression of TWEAK/Fn14 in renal tissues of those patients and assessed the effect of TWEAK in glomerular mesangial cells and podocytes. Results The levels of uTWEAK in the patients with IgAN and other renal diseases were significantly higher than in the healthy controls (P < 0.001). In the IgAN patients, the levels of uTWEAK correlated significantly with urinary protein excretion and extracapillary proliferation (r = 0.54, P < 0.001 and r = 0.32, P < 0.001, respectively). In a comparison of the levels of uTWEAK at diagnosis with that of follow-up, the levels of uTWEAK in patients with clinical and partial remission decreased significantly. We showed not only increased expression of both TWEAK and Fn14 in IgAN patients with glomerular crescents but also TWEAK-induced cell motility in podocytes. Conclusions The relationship between the levels of uTWEAK and clinicopathological findings observed in this study suggests that TWEAK/Fn14 system affects crescent formation and proteinuria in patients with IgAN.
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Affiliation(s)
- Yohei Sasaki
- Division of Nephrology, Department of Internal Medicine, Juntendo University Faculty of Medicine, 2-1-1, Hongo, Bunkyo-ku, Tokyo, 113-8421, Japan.
| | - Yoshio Shimizu
- Division of Nephrology, Department of Internal Medicine, Juntendo University Faculty of Medicine, 2-1-1, Hongo, Bunkyo-ku, Tokyo, 113-8421, Japan.
| | - Yusuke Suzuki
- Division of Nephrology, Department of Internal Medicine, Juntendo University Faculty of Medicine, 2-1-1, Hongo, Bunkyo-ku, Tokyo, 113-8421, Japan.
| | - Satoshi Horikoshi
- Division of Nephrology, Department of Internal Medicine, Juntendo University Faculty of Medicine, 2-1-1, Hongo, Bunkyo-ku, Tokyo, 113-8421, Japan.
| | - Yasuhiko Tomino
- Division of Nephrology, Department of Internal Medicine, Juntendo University Faculty of Medicine, 2-1-1, Hongo, Bunkyo-ku, Tokyo, 113-8421, Japan.
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Seki T, Asanuma K, Asao R, Nonaka K, Sasaki Y, Oliva Trejo JA, Kurosawa H, Hirayama Y, Horikoshi S, Tomino Y, Saito A. Significance of urinary full-length megalin in patients with IgA nephropathy. PLoS One 2014; 9:e114400. [PMID: 25502002 PMCID: PMC4264761 DOI: 10.1371/journal.pone.0114400] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2014] [Accepted: 11/10/2014] [Indexed: 11/22/2022] Open
Abstract
Background and Objectives Megalin is highly expressed at the apical membranes of proximal tubular epithelial cells. A urinary full-length megalin (C-megalin) assay is linked to the severity of diabetic nephropathy in type 2 diabetes. This study examined the relationship between levels of urinary C-megalin and histological findings in adult patients with IgA nephropathy (IgAN). Design, Setting, Participants, & Measurements Urine samples voided in the morning on the day of renal biopsy were obtained from 73 patients with IgAN (29 men and 44 women; mean age, 33 years) and 5 patients with membranous nephropathy (MN). Renal pathologic variables were analyzed using the Oxford classification of IgAN, the Shigematsu classification and the Clinical Guidelines of IgAN in Japan. The levels of urinary C-megalin were measured by sandwich ELISA. Results Histological analysis based on the Oxford classification revealed that the levels of urinary C-megalin were correlated with mesangial hypercellularity in IgAN patients (OR = 1.76, 95% CI: 1.04–3.27, P<0.05). There was a significant correlation between the levels of urinary C-megalin and the severity of chronic extracapillary abnormalities according to the Shigematsu classification in IgAN patients (β = 0.33, P = 0.008). The levels of urinary C-megalin were significantly higher in all risk levels of IgAN patients requiring dialysis using the Clinical Guidelines of IgAN in Japan than in the control group. The levels of urinary C-megalin were significantly higher in the high risk and very high risk grades than in the low risk grade (P<0.05). The levels of urinary C-megalin were significantly higher in MN patients compared to the control group. Conclusions The levels of urinary C-megalin are associated with histological abnormalities in adult IgAN patients. There is a possibility that urinary C-megalin is an independent predictor of disease progression of IgAN. In addition, our results suggest that urinary C-megalin is a marker of glomerular abnormalities in various glomerular diseases as well as IgAN.
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Affiliation(s)
- Takuto Seki
- Division of Nephrology, Juntendo University Faculty of Medicine, Tokyo, Japan; TMK project, Medical Innovation Center, Kyoto University Graduate School of Medicine, Kyoto, Japan
| | - Katsuhiko Asanuma
- Division of Nephrology, Juntendo University Faculty of Medicine, Tokyo, Japan; TMK project, Medical Innovation Center, Kyoto University Graduate School of Medicine, Kyoto, Japan
| | - Rin Asao
- Division of Nephrology, Juntendo University Faculty of Medicine, Tokyo, Japan
| | - Kanae Nonaka
- Division of Nephrology, Juntendo University Faculty of Medicine, Tokyo, Japan; TMK project, Medical Innovation Center, Kyoto University Graduate School of Medicine, Kyoto, Japan
| | - Yu Sasaki
- Division of Nephrology, Juntendo University Faculty of Medicine, Tokyo, Japan
| | | | - Hiroyuki Kurosawa
- Reagents Development Department, Denka Seiken Co. Ltd., Niigata, Japan
| | - Yoshiaki Hirayama
- Reagents Development Department, Denka Seiken Co. Ltd., Niigata, Japan
| | - Satoshi Horikoshi
- Division of Nephrology, Juntendo University Faculty of Medicine, Tokyo, Japan
| | - Yasuhiko Tomino
- Division of Nephrology, Juntendo University Faculty of Medicine, Tokyo, Japan
| | - Akihiko Saito
- Department of Applied Molecular Medicine, Niigata University Graduate School of Medicine and Dental Sciences, Niigata, Japan
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Salih M, Zietse R, Hoorn EJ. Urinary extracellular vesicles and the kidney: biomarkers and beyond. Am J Physiol Renal Physiol 2014; 306:F1251-9. [DOI: 10.1152/ajprenal.00128.2014] [Citation(s) in RCA: 126] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
Extracellular vesicles have been isolated in various body fluids, including urine. The cargo of urinary extracellular vesicles (uEVs) is composed of proteins and nucleic acids reflecting the physiological and possibly pathophysiological state of cells lining the nephron. Because urine is a noninvasive and readily available biofluid, the discovery of uEVs has opened a new field of biomarker research. Their potential use as diagnostic, prognostic, or therapeutic biomarkers for various kidney diseases, including glomerulonephritis, acute kidney injury, tubular disorders, and polycystic kidney disease, is currently being explored. Some challenges, however, remain. These challenges include the need to standardize isolation methods, normalization between samples, and validation of candidate biomarkers. Also, the development of a high-throughput platform to isolate and analyze uEVs, for example, an enzyme-linked immunosorbent assay, is desirable. Here, we review recent studies on uEVs dealing with kidney physiology and pathophysiology. Furthermore, we discuss new and exciting developments regarding vesicles, including their role in cell-to-cell communication and the possibility of using vesicles as a therapy for kidney disorders.
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Affiliation(s)
- Mahdi Salih
- Department of Internal Medicine, Nephrology and Transplantation, Erasmus Medical Center, Rotterdam, The Netherlands
| | - Robert Zietse
- Department of Internal Medicine, Nephrology and Transplantation, Erasmus Medical Center, Rotterdam, The Netherlands
| | - Ewout J. Hoorn
- Department of Internal Medicine, Nephrology and Transplantation, Erasmus Medical Center, Rotterdam, The Netherlands
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50
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Rodrigues PG, Bringhenti RN, do Nascimento JF, Joelsons G, dos Santos M, Pereira S, Veronese FV. Expression patterns of podocyte-associated mRNAs in patients with proliferative or non-proliferative glomerulopathies. INTERNATIONAL JOURNAL OF CLINICAL AND EXPERIMENTAL PATHOLOGY 2014; 7:2185-2198. [PMID: 24966927 PMCID: PMC4069963] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Received: 02/17/2014] [Accepted: 03/03/2014] [Indexed: 06/03/2023]
Abstract
AIM It is not clear how the podocyte damage manifests in different glomerulopathies. This study evaluated the podocyte-associated mRNA profiles in renal tissue and urine of patients with proliferative (PGs) or non-proliferative (NPGs) glomerulopathies. METHODS Messenger RNA levels of nephrin, podocin, podocalyxin, synaptopodin, and alpha-actinin-4 were measured in the kidney tissue and urinary cells by real-time polymerase chain reaction. Podocyte-associated mRNAs were correlated with proteinuria and renal function, and the effect of immunosuppressive treatment of PGs and NPGs on urine mRNAs was assessed up to one year of follow up. RESULTS Podocyte-associated mRNAs were expressed consistently less in kidney tissue from patients with NPGs, and urinary podocyte mRNA levels were significantly higher in the PG group. After six months of immunosuppressive therapy, patients with PGs showed a significant reduction in the expression of podocin, podocalyxin, and alpha-actinin-4 compared with baseline (p<0.001). In the NPG group, alpha-actinin-4 levels decreased (p=0.008), and there was also a trend toward reduced podocalyxin mRNA (p=0.08). Urine podocyte-associated mRNAs correlated with the level of proteinuria at baseline and at six months, and there was a trend toward an inverse correlation between urinary mRNAs and kidney function at one year of follow up. CONCLUSIONS Podocyte-associated mRNAs were inhibited in kidney tissue concomitantly with their increase in urine in these patients with glomerulopathies. Different profiles of mRNA expression were seen, pointing to a higher degree of intra-renal podocytopenia in the NPGs and of podocyturia in the PGs. The immunosuppressive therapy effectively reduced the urinary levels of podocyte-associated mRNAs.
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Affiliation(s)
- Patrícia Garcia Rodrigues
- Post-Graduate Program in Medicine: Medical Sciences, Federal University of Rio Grande do SulPorto Alegre, RS, Brazil
| | | | | | - Gabriel Joelsons
- Post-Graduate Program in Medicine: Medical Sciences, Federal University of Rio Grande do SulPorto Alegre, RS, Brazil
| | - Mariane dos Santos
- Post-Graduate Program in Medicine: Medical Sciences, Federal University of Rio Grande do SulPorto Alegre, RS, Brazil
| | - Sane Pereira
- Post-Graduate Program in Medicine: Medical Sciences, Federal University of Rio Grande do SulPorto Alegre, RS, Brazil
| | - Francisco Veríssimo Veronese
- Post-Graduate Program in Medicine: Medical Sciences, Federal University of Rio Grande do SulPorto Alegre, RS, Brazil
- Division of Nephrology, Hospital de Clínicas de Porto AlegrePorto Alegre, RS, Brazil
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