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Al-Diab O, Sünkel C, Blanc E, Catar RA, Ashraf MI, Zhao H, Wang P, Rinschen MM, Fritsche-Guenther R, Grahammer F, Bachmann S, Beule D, Kirwan JA, Rajewsky N, Huber TB, Gürgen D, Kusch A. Sex-specific molecular signature of mouse podocytes in homeostasis and in response to pharmacological challenge with rapamycin. Biol Sex Differ 2024; 15:72. [PMID: 39278930 PMCID: PMC11404044 DOI: 10.1186/s13293-024-00647-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/26/2023] [Accepted: 08/30/2024] [Indexed: 09/18/2024] Open
Abstract
BACKGROUND Sex differences exist in the prevalence and progression of major glomerular diseases. Podocytes are the essential cell-type in the kidney which maintain the physiological blood-urine barrier, and pathological changes in podocyte homeostasis are critical accelerators of impairment of kidney function. However, sex-specific molecular signatures of podocytes under physiological and stress conditions remain unknown. This work aimed at identifying sexual dimorphic molecular signatures of podocytes under physiological condition and pharmacologically challenged homeostasis with mechanistic target of rapamycin (mTOR) inhibition. mTOR is a crucial regulator involved in a variety of physiological and pathological stress responses in the kidney and inhibition of this pathway may therefore serve as a general stress challenger to get fundamental insights into sex differences in podocytes. METHODS The genomic ROSAmT/mG-NPHS2 Cre mouse model was used which allows obtaining highly pure podocyte fractions for cell-specific molecular analyses, and vehicle or pharmacologic treatment with the mTOR inhibitor rapamycin was performed for 3 weeks. Subsequently, deep RNA sequencing and proteomics were performed of the isolated podocytes to identify intrinsic sex differences. Studies were supplemented with metabolomics from kidney cortex tissues. RESULTS Although kidney function and morphology remained normal in all experimental groups, RNA sequencing, proteomics and metabolomics revealed strong intrinsic sex differences in the expression levels of mitochondrial, translation and structural transcripts, protein abundances and regulation of metabolic pathways. Interestingly, rapamycin abolished prominent sex-specific clustering of podocyte gene expression and induced major changes only in male transcriptome. Several sex-biased transcription factors could be identified as possible upstream regulators of these sexually dimorphic responses. Concordant to transcriptomics, metabolomic changes were more prominent in males. Remarkably, high number of previously reported kidney disease genes showed intrinsic sexual dimorphism and/or different response patterns towards mTOR inhibition. CONCLUSIONS Our results highlight remarkable intrinsic sex-differences and sex-specific response patterns towards pharmacological challenged podocyte homeostasis which might fundamentally contribute to sex differences in kidney disease susceptibilities and progression. This work provides rationale and an in-depth database for novel targets to be tested in specific kidney disease models to advance with sex-specific treatment strategies.
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Affiliation(s)
- Ola Al-Diab
- Department of Nephrology and Medical Intensive Care, Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Charitéplatz 1, 10117, Berlin, Germany
| | - Christin Sünkel
- Berlin Institute for Medical Systems Biology (BIMSB), Max Delbrück Center for Molecular Medicine in the Helmholtz Association, Hannoversche Str 28, 10115, Berlin, Germany
| | - Eric Blanc
- Core Unit Bioinformatics, Berlin Institute of Health at Charité - Universitätsmedizin Berlin, Charitéplatz 1, 10117, Berlin, Germany
| | - Rusan Ali Catar
- Department of Nephrology and Medical Intensive Care, Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Charitéplatz 1, 10117, Berlin, Germany
| | - Muhammad Imtiaz Ashraf
- Department of Surgery, Experimental Surgery, Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Augustenburger Platz 1, 13353, Berlin, Germany
| | - Hongfan Zhao
- Department of Nephrology and Medical Intensive Care, Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Charitéplatz 1, 10117, Berlin, Germany
- Department of Urology, Xijing Hospital, Fourth Military Medical University, Xi'an, Shaanxi, China
| | - Pinchao Wang
- Department of Nephrology and Medical Intensive Care, Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Charitéplatz 1, 10117, Berlin, Germany
| | - Markus M Rinschen
- III. Department of Medicine, University Hospital Hamburg Eppendorf, Martinistraße 52, 20246, Hamburg, Germany
- Department of Biomedicine, Aarhus University, Aarhus, Denmark
| | - Raphaela Fritsche-Guenther
- Metabolomics Platform, Berlin Institute of Health at Charité - Universitätsmedizin Berlin, Lindenberger Weg 80, 10117, Berlin, Germany
| | - Florian Grahammer
- III. Department of Medicine, University Hospital Hamburg Eppendorf, Martinistraße 52, 20246, Hamburg, Germany
| | - Sebastian Bachmann
- Institute of Functional Anatomy, Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Charitéplatz 1, 10117, Berlin, Germany
| | - Dieter Beule
- Core Unit Bioinformatics, Berlin Institute of Health at Charité - Universitätsmedizin Berlin, Charitéplatz 1, 10117, Berlin, Germany
| | - Jennifer A Kirwan
- Metabolomics Platform, Berlin Institute of Health at Charité - Universitätsmedizin Berlin, Lindenberger Weg 80, 10117, Berlin, Germany
| | - Nikolaus Rajewsky
- Berlin Institute for Medical Systems Biology (BIMSB), Max Delbrück Center for Molecular Medicine in the Helmholtz Association, Hannoversche Str 28, 10115, Berlin, Germany
- Department of Pediatric Oncology and Hematology, Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Augustenburger Platz 1, 13353, Berlin, Germany
| | - Tobias B Huber
- III. Department of Medicine, University Hospital Hamburg Eppendorf, Martinistraße 52, 20246, Hamburg, Germany
| | - Dennis Gürgen
- Experimental Pharmacology & Oncology Berlin-Buch GmbH, 13125 Berlin-Buch, Germany
| | - Angelika Kusch
- Department of Nephrology and Medical Intensive Care, Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Charitéplatz 1, 10117, Berlin, Germany.
- BIH Biomedical Innovation Academy (BIA), Berlin Institute of Health at Charité - Universitätsmedizin Berlin, Charitéplatz 1, 10117, Berlin, Germany.
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Higashi AY, Saito AC, Higashi T, Furuse K, Furuse M, Chiba H, Kazama JJ. Bicellular Localization of Tricellular Junctional Protein Angulin-3/ILDR2 Allows Detection of Podocyte Injury. THE AMERICAN JOURNAL OF PATHOLOGY 2024; 194:673-683. [PMID: 38311119 DOI: 10.1016/j.ajpath.2024.01.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/06/2023] [Revised: 12/19/2023] [Accepted: 01/18/2024] [Indexed: 02/06/2024]
Abstract
Podocytes serve as part of the renal filtration unit with slit diaphragms. Although the structure of slit diaphragms between two cells is well characterized, how the tricellular contact of podocytes is organized and how it changes in injured podocytes remains unknown. This study focused on a tricellular junction protein, angulin-3, and its localization in healthy podocytes, in developmental stages, and in pathologic conditions, using a newly established monoclonal antibody. Angulin-3 was confined at tricellular junctions of primordial podocytes, then transiently localized at bicellular junctions as foot process interdigitation developed and the intercellular junctions rearranged into slit diaphragm, and eventually distributed in a sparse punctate pattern on the foot processes of adult podocytes. In the rodent podocyte injury models, angulin-3 showed bicellular localization between the foot processes, and the localization turned from punctate to dashed linear pattern along the effaced foot processes with the progression of podocyte injury. Angulin-3 also accumulated between foot processes in a linear pattern in kidney biopsy samples of human nephrotic syndrome. Additionally, the line length of angulin-3 staining signal correlated with risk of relapse under glucocorticoid therapy in patients with minimal change nephrotic syndrome. This study proposes an image program to score the linearity of the accumulation pattern of angulin-3 to evaluate the relapse risk of patients with minimal change nephrotic syndrome.
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Affiliation(s)
- Atsuko Y Higashi
- Department of Nephrology and Hypertension, Fukushima Medical University, Fukushima, Japan.
| | - Akira C Saito
- Department of Basic Pathology, Fukushima Medical University, Fukushima, Japan
| | - Tomohito Higashi
- Department of Basic Pathology, Fukushima Medical University, Fukushima, Japan
| | - Kyoko Furuse
- Division of Cell Structure, National Institute for Physiological Sciences, Okazaki, Japan
| | - Mikio Furuse
- Division of Cell Structure, National Institute for Physiological Sciences, Okazaki, Japan; Department of Physiological Sciences, School of Life Science, SOKENDAI (Graduate University for Advanced Studies), Okazaki, Japan
| | - Hideki Chiba
- Department of Basic Pathology, Fukushima Medical University, Fukushima, Japan
| | - Junichiro J Kazama
- Department of Nephrology and Hypertension, Fukushima Medical University, Fukushima, Japan
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3
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Waller AP, Wolfgang KJ, Pruner I, Stevenson ZS, Abdelghani E, Muralidharan K, Wilkie TK, Blissett AR, Calomeni EP, Vetter TA, Brodsky SV, Smoyer WE, Nieman MT, Kerlin BA. Prothrombin Knockdown Protects Podocytes and Reduces Proteinuria in Glomerular Disease. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2023.06.20.544360. [PMID: 38464017 PMCID: PMC10925217 DOI: 10.1101/2023.06.20.544360] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/12/2024]
Abstract
Chronic kidney disease (CKD) is a leading cause of death, and its progression is driven by glomerular podocyte injury and loss, manifesting as proteinuria. Proteinuria includes urinary loss of coagulation zymogens, cofactors, and inhibitors. Importantly, both CKD and proteinuria significantly increase the risk of thromboembolic disease. Prior studies demonstrated that anticoagulants reduced proteinuria in rats and that thrombin injured cultured podocytes. Herein we aimed to directly determine the influence of circulating prothrombin on glomerular pathobiology. We hypothesized that (pro)thrombin drives podocytopathy, podocytopenia, and proteinuria. Glomerular proteinuria was induced with puromycin aminonucleoside (PAN) in Wistar rats. Circulating prothrombin was either knocked down using a rat-specific antisense oligonucleotide or elevated by serial intravenous infusions of prothrombin protein, which are previously established methods to model hypo- (LoPT) and hyper-prothrombinemia (HiPT), respectively. After 10 days (peak proteinuria in this model) plasma prothrombin levels were determined, kidneys were examined for (pro)thrombin co-localization to podocytes, histology, and electron microscopy. Podocytopathy and podocytopenia were determined and proteinuria, and plasma albumin were measured. LoPT significantly reduced prothrombin colocalization to podocytes, podocytopathy, and proteinuria with improved plasma albumin. In contrast, HiPT significantly increased podocytopathy and proteinuria. Podocytopenia was significantly reduced in LoPT vs. HiPT rats. In summary, prothrombin knockdown ameliorated PAN-induced glomerular disease whereas hyper-prothrombinemia exacerbated disease. Thus, (pro)thrombin antagonism may be a viable strategy to simultaneously provide thromboprophylaxis and prevent podocytopathy-mediated CKD progression.
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Guo H, Rogg M, Keller J, Scherzinger AK, Jäckel J, Meyer C, Sammarco A, Helmstädter M, Gorka O, Groß O, Schell C, Bechtel-Walz W. ADP-Ribosylation Factor-Interacting Protein 2 Acts as a Novel Regulator of Mitophagy and Autophagy in Podocytes in Diabetic Nephropathy. Antioxidants (Basel) 2024; 13:81. [PMID: 38247505 PMCID: PMC10812550 DOI: 10.3390/antiox13010081] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2023] [Revised: 12/22/2023] [Accepted: 01/03/2024] [Indexed: 01/23/2024] Open
Abstract
(1) Background: Differentiated podocytes are particularly vulnerable to oxidative stress and cellular waste products. The disease-related loss of postmitotic podocytes is a direct indicator of renal disease progression and aging. Podocytes use highly specific regulated networks of autophagy and endocytosis that counteract the increasing number of damaged protein aggregates and help maintain cellular homeostasis. Here, we demonstrate that ARFIP2 is a regulator of autophagy and mitophagy in podocytes both in vitro and in vivo. (2) Methods: In a recent molecular regulatory network analysis of mouse glomeruli, we identified ADP-ribosylation factor-interacting protein 2 (Arfip2), a cytoskeletal regulator and cofactor of ATG9-mediated autophagosome formation, to be differentially expressed with age. We generated an Arfip2-deficient immortalized podocyte cell line using the CRISPR/Cas technique to investigate the significance of Arfip2 for renal homeostasis in vitro. For the in vivo analyses of Arfip2 deficiency, we used a mouse model of Streptozotozin-induced type I diabetes and investigated physiological data and (patho)histological (ultra)structural modifications. (3) Results: ARFIP2 deficiency in immortalized human podocytes impedes autophagy. Beyond this, ARFIP2 deficiency in human podocytes interferes with ATG9A trafficking and the PINK1-Parkin pathway, leading to the compromised fission of mitochondria and short-term increase in mitochondrial respiration and induction of mitophagy. In diabetic mice, Arfip2 deficiency deteriorates autophagy and leads to foot process effacement, histopathological changes, and early albuminuria. (4) Conclusions: In summary, we show that ARFIP2 is a novel regulator of autophagy and mitochondrial homeostasis in podocytes by facilitating ATG9A trafficking during PINK1/Parkin-regulated mitophagy.
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Affiliation(s)
- Haihua Guo
- Department of Medicine IV, University Medical Center, Faculty of Medicine, University of Freiburg, 79106 Freiburg, Germany
| | - Manuel Rogg
- Institute of Surgical Pathology, Medical Center, Faculty of Medicine, University of Freiburg, 79106 Freiburg, Germany
| | - Julia Keller
- Department of Medicine IV, University Medical Center, Faculty of Medicine, University of Freiburg, 79106 Freiburg, Germany
- Faculty of Biology, University of Freiburg, 79106 Freiburg, Germany
| | - Ann-Kathrin Scherzinger
- Department of Medicine IV, University Medical Center, Faculty of Medicine, University of Freiburg, 79106 Freiburg, Germany
- Faculty of Biology, University of Freiburg, 79106 Freiburg, Germany
| | - Julia Jäckel
- Department of Medicine IV, University Medical Center, Faculty of Medicine, University of Freiburg, 79106 Freiburg, Germany
| | - Charlotte Meyer
- Department of Medicine IV, University Medical Center, Faculty of Medicine, University of Freiburg, 79106 Freiburg, Germany
| | - Alena Sammarco
- Institute of Surgical Pathology, Medical Center, Faculty of Medicine, University of Freiburg, 79106 Freiburg, Germany
| | - Martin Helmstädter
- Department of Medicine IV, University Medical Center, Faculty of Medicine, University of Freiburg, 79106 Freiburg, Germany
- EMcore, Renal Division, University Medical Center, Faculty of Medicine, University of Freiburg, 79106 Freiburg, Germany
| | - Oliver Gorka
- Institute of Neuropathology, Experimental Neuropathology, University Medical Center, Faculty of Medicine, University of Freiburg, 79106 Freiburg, Germany
| | - Olaf Groß
- Institute of Neuropathology, Experimental Neuropathology, University Medical Center, Faculty of Medicine, University of Freiburg, 79106 Freiburg, Germany
| | - Christoph Schell
- Institute of Surgical Pathology, Medical Center, Faculty of Medicine, University of Freiburg, 79106 Freiburg, Germany
- Freiburg Institute for Advanced Studies (FRIAS), University of Freiburg, 79106 Freiburg, Germany
| | - Wibke Bechtel-Walz
- Department of Medicine IV, University Medical Center, Faculty of Medicine, University of Freiburg, 79106 Freiburg, Germany
- Berta-Ottenstein Program, Faculty of Medicine, University of Freiburg, 79106 Freiburg, Germany
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5
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Gerlach GF, Imseis ZH, Cooper SL, Santos AN, O’Brien LL. Mapping of the podocin proximity-dependent proteome reveals novel components of the kidney podocyte foot process. Front Cell Dev Biol 2023; 11:1195037. [PMID: 37325559 PMCID: PMC10262054 DOI: 10.3389/fcell.2023.1195037] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2023] [Accepted: 05/03/2023] [Indexed: 06/17/2023] Open
Abstract
Introduction: The unique architecture of glomerular podocytes is integral to kidney filtration. Interdigitating foot processes extend from the podocyte cell body, wrap around fenestrated capillaries, and form specialized junctional complexes termed slit diaphragms to create a molecular sieve. However, the full complement of proteins which maintain foot process integrity, and how this localized proteome changes with disease, remain to be elucidated. Methods: Proximity-dependent biotin identification (BioID) enables the identification of spatially localized proteomes. To this end, we developed a novel in vivo BioID knock-in mouse model. We utilized the slit diaphragm protein podocin (Nphs2) to create a podocin-BioID fusion. Podocin-BioID localizes to the slit diaphragm, and biotin injection leads to podocyte-specific protein biotinylation. We isolated the biotinylated proteins and performed mass spectrometry to identify proximal interactors. Results and Discussion: Gene ontology analysis of 54 proteins specifically enriched in our podocin-BioID sample revealed 'cell junctions,' 'actin binding,' and 'cytoskeleton organization' as top terms. Known foot process components were identified, and we further uncovered two novel proteins: the tricellular junctional protein Ildr2 and the CDC42 and N-WASP interactor Fnbp1l. We confirmed that Ildr2 and Fnbp1l are expressed by podocytes and partially colocalize with podocin. Finally, we investigated how this proteome changes with age and uncovered a significant increase in Ildr2. This was confirmed by immunofluorescence on human kidney samples and suggests altered junctional composition may preserve podocyte integrity. Together, these assays have led to new insights into podocyte biology and support the efficacy of utilizing BioID in vivo to interrogate spatially localized proteomes in health, aging, and disease.
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Affiliation(s)
| | | | | | | | - Lori L. O’Brien
- Department of Cell Biology and Physiology, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States
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6
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Frommherz LH, Sayar SB, Wang Y, Trefzer LK, He Y, Leppert J, Eßer P, Has C. Integrin α3 negative podocytes: A gene expression study. Matrix Biol Plus 2022; 16:100119. [PMID: 36060790 PMCID: PMC9429797 DOI: 10.1016/j.mbplus.2022.100119] [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: 09/26/2021] [Revised: 07/30/2022] [Accepted: 08/07/2022] [Indexed: 12/04/2022] Open
Abstract
New cell model to investigate the impact of loss of integrin α3 in podocytes. In this novel model, genes of the extracellular matrix and adhesome are mostly downregulated. Loss of integrin α3 results in changes of cell adhesion and spreading.
Integrin α3β1 is a cell adhesion receptor widely expressed in epithelial cells. Pathogenic variants in the gene encoding the integrin α3 subunit ITGA3 lead to a syndrome including interstitial lung disease, nephrotic syndrome, and epidermolysis bullosa (ILNEB). Renal involvement mainly consists of glomerular disease caused by loss of adhesion between podocytes and the glomerular basement membrane. The aim of this study was to characterize the impact of loss of integrin α3 on human podocytes. ITGA3 was stably knocked-out in the human podocyte cell line AB8/13, designated as PodoA3−, and in human proximal tubule epithelial cell line HK2 using the targeted genome editing technique CRISPR/Cas9. Cell clones were characterized by Sanger sequencing, quantitative PCR, Western Blot and immunofluorescence staining. RNASeq of integrin α3 negative cells and controls was performed to identify differential gene expression patterns. Differentiated PodoA3− did not substantially change morphology and adhesion under standard culture conditions, but displayed significantly reduced spreading and adhesion when seed on laminin 511 in serum free medium. Gene expression studies demonstrated a distinct dysregulation of the adhesion network with downregulation of most integrin α3 interaction partners. In agreement with this, biological processes such as “extracellular matrix organization” and “cell differentiation” as well as KEGG pathways such as “ECM-receptor interaction”, “focal adhesion” and the “PI3K-Akt signaling pathway” were significantly downregulated in human podocytes lacking the integrin α3 subunit.
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Affiliation(s)
- L H Frommherz
- Department of Dermatology, Medical Center - University of Freiburg, Freiburg, Germany.,Department of Dermatology and Allergology, University Hospital, LMU Munich, Germany
| | - S B Sayar
- Department of Dermatology, Medical Center - University of Freiburg, Freiburg, Germany
| | - Y Wang
- Department of Dermatology, Medical Center - University of Freiburg, Freiburg, Germany
| | - L K Trefzer
- Department of Dermatology, Medical Center - University of Freiburg, Freiburg, Germany
| | - Y He
- Department of Dermatology, Medical Center - University of Freiburg, Freiburg, Germany
| | - J Leppert
- Department of Dermatology, Medical Center - University of Freiburg, Freiburg, Germany
| | - P Eßer
- Department of Dermatology, Medical Center - University of Freiburg, Freiburg, Germany
| | - C Has
- Department of Dermatology, Medical Center - University of Freiburg, Freiburg, Germany
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7
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A slit-diaphragm-associated protein network for dynamic control of renal filtration. Nat Commun 2022; 13:6446. [PMID: 36307401 PMCID: PMC9616960 DOI: 10.1038/s41467-022-33748-1] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2022] [Accepted: 09/29/2022] [Indexed: 12/25/2022] Open
Abstract
The filtration of blood in the kidney which is crucial for mammalian life is determined by the slit-diaphragm, a cell-cell junction between the foot processes of renal podocytes. The slit-diaphragm is thought to operate as final barrier or as molecular sensor of renal filtration. Using high-resolution proteomic analysis of slit-diaphragms affinity-isolated from rodent kidney, we show that the native slit-diaphragm is built from the junction-forming components Nephrin, Neph1 and Podocin and a co-assembled high-molecular weight network of proteins. The network constituents cover distinct classes of proteins including signaling-receptors, kinases/phosphatases, transporters and scaffolds. Knockout or knock-down of either the core components or the selected network constituents tyrosine kinase MER (MERTK), atrial natriuretic peptide-receptor C (ANPRC), integral membrane protein 2B (ITM2B), membrane-associated guanylate-kinase, WW and PDZ-domain-containing protein1 (MAGI1) and amyloid protein A4 resulted in target-specific impairment or disruption of the filtration process. Our results identify the slit-diaphragm as a multi-component system that is endowed with context-dependent dynamics via a co-assembled protein network.
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8
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Li X, Venkatesh I, Villanueva V, Wei H, Geraghty T, Rajagopalan A, Helmuth RW, Altintas MM, Faridi HM, Gupta V. Podocyte-specific deletion of miR-146a increases podocyte injury and diabetic kidney disease. Front Med (Lausanne) 2022; 9:897188. [PMID: 36059820 PMCID: PMC9433550 DOI: 10.3389/fmed.2022.897188] [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] [Subscribe] [Scholar Register] [Received: 03/15/2022] [Accepted: 07/26/2022] [Indexed: 11/13/2022] Open
Abstract
Diabetic glomerular injury is a major complication of diabetes mellitus and is the leading cause of end stage renal disease (ESRD). Healthy podocytes are essential for glomerular function and health. Injury or loss of these cells results in increased proteinuria and kidney dysfunction and is a common finding in various glomerulopathies. Thus, mechanistic understanding of pathways that protect podocytes from damage are essential for development of future therapeutics. MicroRNA-146a (miR-146a) is a negative regulator of inflammation and is highly expressed in myeloid cells and podocytes. We previously reported that miR-146a levels are significantly reduced in the glomeruli of patients with diabetic nephropathy (DN). Here we report generation of mice with selective deletion of miR-146a in podocytes and use of these mice in models of glomerular injury. Induction of glomerular injury in C57BL/6 wildtype mice (WT) and podocyte-specific miR-146a knockout (Pod-miR146a-/-) animals via administration of low-dose lipopolysaccharide (LPS) or nephrotoxic serum (NTS) resulted in increased proteinuria in the knockout mice, suggesting that podocyte-expressed miR-146a protects these cells, and thus glomeruli, from damage. Furthermore, induction of hyperglycemia using streptozotocin (STZ) also resulted in an accelerated development of glomerulopathy and a rapid increase in proteinuria in the knockout animals, as compared to the WT animals, further confirming the protective role of podocyte-expressed miR-146a. We also confirmed that the direct miR-146a target, ErbB4, was significantly upregulated in the diseased glomeruli and erlotinib, an ErbB4 and EGFR inhibitor, reducedits upregulation and the proteinuria in treated animals. Primary miR146-/- podocytes from these animals also showed a basally upregulated TGFβ-Smad3 signaling in vitro. Taken together, this study shows that podocyte-specific miR-146a is imperative for protecting podocytes from glomerular damage, via modulation of ErbB4/EGFR, TGFβ, and linked downstream signaling.
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Affiliation(s)
- Xiaobo Li
- Department of Internal Medicine, Drug Discovery Center, Rush University Medical Center, Chicago, IL, United States
| | - Ishwarya Venkatesh
- Department of Internal Medicine, Drug Discovery Center, Rush University Medical Center, Chicago, IL, United States
| | - Veronica Villanueva
- Department of Internal Medicine, Drug Discovery Center, Rush University Medical Center, Chicago, IL, United States
| | - Huiting Wei
- Department of Pathology, The First Affiliated Hospital Sun Yat-sen University, Guangzhou, China
| | - Terese Geraghty
- Department of Internal Medicine, Drug Discovery Center, Rush University Medical Center, Chicago, IL, United States
| | - Anugraha Rajagopalan
- Department of Internal Medicine, Drug Discovery Center, Rush University Medical Center, Chicago, IL, United States
| | - Richard W. Helmuth
- Department of Internal Medicine, Drug Discovery Center, Rush University Medical Center, Chicago, IL, United States
| | - Mehmet M. Altintas
- Department of Internal Medicine, Drug Discovery Center, Rush University Medical Center, Chicago, IL, United States
| | - Hafeez M. Faridi
- College of Pharmacy, Chicago State University, Chicago, IL, United States
| | - Vineet Gupta
- Department of Internal Medicine, Drug Discovery Center, Rush University Medical Center, Chicago, IL, United States
- Division of Hematology, Oncology and Cellar Therapies, Department of Internal Medicine, Rush University Medical Center, Chicago, IL, United States
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9
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Hutzfeldt AD, Tan Y, Bonin LL, Beck BB, Baumbach J, Lassé M, Demir F, Rinschen MM. Consensus draft of the native mouse podocyte-ome. Am J Physiol Renal Physiol 2022; 323:F182-F197. [PMID: 35796460 DOI: 10.1152/ajprenal.00058.2022] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The podocyte is a key cell in maintaining renal filtration barrier integrity. Several recent studies have analyzed the entity of genome-coded molecules in the podocyte at deep resolution. This avenue of "podocyte-ome" research was enabled by a variety of techniques, including single-cell transcriptomics, FACS-sorting with and without genetically encoded markers, and deep acquisition of proteomics. However, data across various omics studies are not well-integrated with each other. Here, we aim to establish a common, simplified knowledgebase for the mouse "podocyte-ome" by integrating bulk RNA sequencing and bulk proteomics of sorted podocytes and single cell transcriptomics. Three datasets of each omics type from different laboratories, respectively, were integrated, visualized and bioinformatically analyzed. The procedure sheds light on conserved processes of podocytes, but also on limitations and specific features of the used technologies. High expression of glycan GPI anchor synthesis and turnover, and retinol metabolism was identified as a relatively understudied feature of podocytes, while there are both podocyte-enriched and podocyte-depleted actin binding molecules. We compiled aggregated data in an application that illustrates the features of the dataset and allows for exploratory analyses through individual gene query of podocyte identity in absolute and relative quantification towards other glomerular cell types, keywords, GO-terms and gene set enrichments. This consensus draft is a first step towards common molecular omics knowledge of kidney cells.
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Affiliation(s)
- Arvid D Hutzfeldt
- III Department of Medicine, grid.13648.38University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Yifan Tan
- Department of Biomedicine, grid.7048.bAarhus University, Aarhus, Denmark
| | - Léna Lydie Bonin
- Department of Biomedicine, grid.7048.bAarhus University, Aarhus, Denmark
| | - Bodo B Beck
- Institute of Human Genetics, Faculty of Medicine and University Hospital Cologne, grid.6190.eUniversity of Cologne, Cologne, Germany
| | - Jan Baumbach
- Institute for Computational Systems Biology, grid.9026.dUniversität Hamburg, Hamburg, Germany
| | - Moritz Lassé
- III Department of Medicine, grid.13648.38University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Fatih Demir
- Department of Biomedicine, grid.7048.bAarhus University, Aarhus, Denmark
| | - Markus M Rinschen
- Department of Biomedicine, grid.7048.bAarhus University, Aarhus, Denmark
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10
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NUP133 Controls Nuclear Pore Assembly, Transcriptome Composition, and Cytoskeleton Regulation in Podocytes. Cells 2022; 11:cells11081259. [PMID: 35455939 PMCID: PMC9025798 DOI: 10.3390/cells11081259] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2022] [Revised: 04/04/2022] [Accepted: 04/05/2022] [Indexed: 02/04/2023] Open
Abstract
Steroid-resistant nephrotic syndrome (SRNS) frequently leads to end-stage renal disease, ultimately requiring kidney replacement therapies. SRNS is often caused by hereditary monogenic mutations, specifically affecting specialized epithelial cells (podocytes) of the glomerular filtration barrier. Mutations in several components of the nuclear pore complex, including NUP133 and NUP107, have been recently identified to cause hereditary SRNS. However, underlying pathomechanisms, eliciting podocyte-specific manifestations of these nucleoporopathies, remained largely elusive. Here, we generated an in vitro model of NUP133-linked nucleoporopathies using CRISPR/Cas9-mediated genome editing in human podocytes. Transcriptome, nuclear pore assembly, and cytoskeleton regulation of NUP133 loss-of-function, mutant, and wild-type podocytes were analyzed. Loss of NUP133 translated into a disruption of the nuclear pore, alterations of the podocyte-specific transcriptome, and impaired cellular protrusion generation. Surprisingly, comparative analysis of the described SRNS-related NUP133 mutations revealed only mild defects. Am impaired protein interaction in the Y-complex and decrease of NUP133 protein levels might be the primary and unifying consequence of mutant variants, leading to a partial loss-of-function phenotype and disease manifestation in susceptible cell types, such as podocytes.
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11
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BECLIN1 Is Essential for Podocyte Secretory Pathways Mediating VEGF Secretion and Podocyte-Endothelial Crosstalk. Int J Mol Sci 2022; 23:ijms23073825. [PMID: 35409185 PMCID: PMC8998849 DOI: 10.3390/ijms23073825] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2022] [Revised: 03/17/2022] [Accepted: 03/29/2022] [Indexed: 02/06/2023] Open
Abstract
Vascular endothelial growth factor A (VEGFA) secretion from podocytes is crucial for maintaining endothelial integrity within the glomerular filtration barrier. However, until now, the molecular mechanisms underlying podocyte secretory function remained unclear. Through podocyte-specific deletion of BECLIN1 (ATG6 or Becn1), a key protein in autophagy initiation, we identified a major role for this molecule in anterograde Golgi trafficking. The Becn1-deficient podocytes displayed aberrant vesicle formation in the trans-Golgi network (TGN), leading to dramatic vesicle accumulation and complex disrupted patterns of intracellular vesicle trafficking and membrane dynamics. Phenotypically, podocyte-specific deletion of Becn1 resulted in early-onset glomerulosclerosis, which rapidly progressed and dramatically reduced mouse life span. Further, in vivo and in vitro studies clearly showed that VEGFA secretion, and thereby endothelial integrity, greatly depended on BECLIN1 availability and function. Being the first to demonstrate the importance of a secretory pathway for podocyte integrity and function, we identified BECLIN1 as a key component in this complex cellular process. Functionally, by promoting VEGFA secretion, a specific secretory pathway emerged as an essential component for the podocyte-endothelial crosstalk that maintains the glomerular filtration barrier.
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12
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Rogg M, Maier JI, Van Wymersch C, Helmstädter M, Sammarco A, Lindenmeyer M, Zareba P, Montanez E, Walz G, Werner M, Endlich N, Benzing T, Huber TB, Schell C. α-Parvin Defines a Specific Integrin Adhesome to Maintain the Glomerular Filtration Barrier. J Am Soc Nephrol 2022; 33:786-808. [PMID: 35260418 PMCID: PMC8970443 DOI: 10.1681/asn.2021101319] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2021] [Accepted: 01/17/2022] [Indexed: 12/19/2022] Open
Abstract
BACKGROUND The cell-matrix adhesion between podocytes and the glomerular basement membrane is essential for the integrity of the kidney's filtration barrier. Despite increasing knowledge about the complexity of integrin adhesion complexes, an understanding of the regulation of these protein complexes in glomerular disease remains elusive. METHODS We mapped the in vivo composition of the podocyte integrin adhesome. In addition, we analyzed conditional knockout mice targeting a gene (Parva) that encodes an actin-binding protein (α-parvin), and murine disease models. To evaluate podocytes in vivo, we used super-resolution microscopy, electron microscopy, multiplex immunofluorescence microscopy, and RNA sequencing. We performed functional analysis of CRISPR/Cas9-generated PARVA single knockout podocytes and PARVA and PARVB double knockout podocytes in three- and two-dimensional cultures using specific extracellular matrix ligands and micropatterns. RESULTS We found that PARVA is essential to prevent podocyte foot process effacement, detachment from the glomerular basement membrane, and the development of FSGS. Through the use of in vitro and in vivo models, we identified an inherent PARVB-dependent compensatory module at podocyte integrin adhesion complexes, sustaining efficient mechanical linkage at the filtration barrier. Sequential genetic deletion of PARVA and PARVB induces a switch in structure and composition of integrin adhesion complexes. This redistribution of these complexes translates into a loss of the ventral actin cytoskeleton, decreased adhesion capacity, impaired mechanical resistance, and dysfunctional extracellular matrix assembly. CONCLUSIONS The findings reveal adaptive mechanisms of podocyte integrin adhesion complexes, providing a conceptual framework for therapeutic strategies to prevent podocyte detachment in glomerular disease.
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Affiliation(s)
- Manuel Rogg
- Institute of Surgical Pathology, Faculty of Medicine, Medical Center-University of Freiburg, Freiburg, Germany
| | - Jasmin I Maier
- Institute of Surgical Pathology, Faculty of Medicine, Medical Center-University of Freiburg, Freiburg, Germany
| | - Clara Van Wymersch
- Institute of Surgical Pathology, Faculty of Medicine, Medical Center-University of Freiburg, Freiburg, Germany
| | - Martin Helmstädter
- Department of Medicine IV, Faculty of Medicine, Medical Center-University of Freiburg, Freiburg, Germany
| | - Alena Sammarco
- Institute of Surgical Pathology, Faculty of Medicine, Medical Center-University of Freiburg, Freiburg, Germany
| | - Maja Lindenmeyer
- III. Department of Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Paulina Zareba
- Institute of Surgical Pathology, Faculty of Medicine, Medical Center-University of Freiburg, Freiburg, Germany
| | - Eloi Montanez
- Department of Physiological Sciences, Faculty of Medicine, University of Barcelona and Health Sciences and Bellvitge Biomedical Research Institute (IDIBELL), Barcelona, Spain
| | - Gerd Walz
- Department of Medicine IV, Faculty of Medicine, Medical Center-University of Freiburg, Freiburg, Germany
| | - Martin Werner
- Institute of Surgical Pathology, Faculty of Medicine, Medical Center-University of Freiburg, Freiburg, Germany
| | - Nicole Endlich
- Department of Anatomy and Cell Biology, University Medicine Greifswald, Greifswald, Germany
| | - Thomas Benzing
- Department II of Internal Medicine and Center for Molecular Medicine Cologne, University of Cologne, Faculty of Medicine and University Hospital Cologne, Cologne, Germany
| | - Tobias B Huber
- III. Department of Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Christoph Schell
- Institute of Surgical Pathology, Faculty of Medicine, Medical Center-University of Freiburg, Freiburg, Germany .,Freiburg Institute for Advanced Studies (FRIAS), University of Freiburg, Freiburg, Germany
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13
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Wonnacott A, Denby L, Coward RJM, Fraser DJ, Bowen T. MicroRNAs and their delivery in diabetic fibrosis. Adv Drug Deliv Rev 2022; 182:114045. [PMID: 34767865 DOI: 10.1016/j.addr.2021.114045] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2021] [Revised: 09/21/2021] [Accepted: 11/04/2021] [Indexed: 12/11/2022]
Abstract
The global prevalence of diabetes mellitus was estimated to be 463 million people in 2019 and is predicted to rise to 700 million by 2045. The associated financial and societal costs of this burgeoning epidemic demand an understanding of the pathology of this disease, and its complications, that will inform treatment to enable improved patient outcomes. Nearly two decades after the sequencing of the human genome, the significance of noncoding RNA expression is still being assessed. The family of functional noncoding RNAs known as microRNAs regulates the expression of most genes encoded by the human genome. Altered microRNA expression profiles have been observed both in diabetes and in diabetic complications. These transcripts therefore have significant potential and novelty as targets for therapy, therapeutic agents and biomarkers.
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Affiliation(s)
- Alexa Wonnacott
- Wales Kidney Research Unit, Division of Infection & Immunity, School of Medicine, College of Biomedical and Life Sciences, Cardiff University, Heath Park, Cardiff CF14 4XN, UK
| | - Laura Denby
- Centre for Cardiovascular Science, Queen's Medical Research Institute, University of Edinburgh, Little France Crescent, Edinburgh EH16 4TJ, UK
| | - Richard J M Coward
- Bristol Renal, Dorothy Hodgkin Building, Bristol Medical School, University of Bristol, Bristol BS1 3NY, UK
| | - Donald J Fraser
- Wales Kidney Research Unit, Division of Infection & Immunity, School of Medicine, College of Biomedical and Life Sciences, Cardiff University, Heath Park, Cardiff CF14 4XN, UK
| | - Timothy Bowen
- Wales Kidney Research Unit, Division of Infection & Immunity, School of Medicine, College of Biomedical and Life Sciences, Cardiff University, Heath Park, Cardiff CF14 4XN, UK.
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14
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Koehler S, Odenthal J, Ludwig V, Jess DU, Höhne M, Jüngst C, Grawe F, Helmstädter M, Janku JL, Bergmann C, Hoyer PF, Hagmann HHH, Walz G, Bloch W, Niessen C, Schermer B, Wodarz A, Denholm B, Benzing T, Iden S, Brinkkoetter PT. Scaffold polarity proteins Par3A and Par3B share redundant functions while Par3B acts independent of atypical protein kinase C/Par6 in podocytes to maintain the kidney filtration barrier. Kidney Int 2021; 101:733-751. [PMID: 34929254 DOI: 10.1016/j.kint.2021.11.030] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2021] [Revised: 11/08/2021] [Accepted: 11/22/2021] [Indexed: 10/19/2022]
Abstract
Glomerular diseases are a major cause for chronic kidney disorders. In most cases podocyte injury is causative for disease development. Cytoskeletal rearrangements and morphological changes are hallmark features of podocyte injury and result in dedifferentiation and loss of podocytes. Here, we establish a link between the Par3 polarity complex and actin regulators necessary to establish and maintain podocyte architecture by utilizing mouse and Drosophila models to characterize the functional role of Par3A and Par3B and its fly homologue Bazooka in vivo. Only simultaneous inactivation of both Par3 proteins caused a severe disease phenotype. Rescue experiments in Drosophila nephrocytes revealed atypical protein kinase C (aPKC)-Par6 dependent and independent effects. While Par3A primarily acts via aPKC-Par6, Par3B function was independent of Par6. Actin-associated synaptopodin protein levels were found to be significantly upregulated upon loss of Par3A/B in mouse podocytes. Tropomyosin2, which shares functional similarities with synaptopodin, was also elevated in Bazooka depleted nephrocytes. The simultaneous depletion of Bazooka and Tropomyosin2 resulted in a partial rescue of the Bazooka knockdown phenotype and prevented increased Rho1, a member of a GTPase protein family regulating the cytoskeleton. The latter contribute to the nephrocyte phenotype observed upon loss of Bazooka. Thus, we demonstrate that Par3 proteins share a high functional redundancy but also have specific functions. Par3A acts in an aPKC-Par6 dependent way and regulates RhoA-GTP levels, while Par3B exploits Par6 independent functions influencing synaptopodin localization. Hence, Par3A and Par3B link elements of polarity signaling and actin regulators to maintain podocyte architecture.
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Affiliation(s)
- Sybille Koehler
- Department II of Internal Medicine; Center for Molecular Medicine Cologne (CMMC), University of Cologne, Faculty of Medicine and University Hospital Cologne, Cologne, Germany; Biomedical Sciences, University of Edinburgh, Edinburgh, Scotland, UK.
| | - Johanna Odenthal
- Department II of Internal Medicine; Center for Molecular Medicine Cologne (CMMC), University of Cologne, Faculty of Medicine and University Hospital Cologne, Cologne, Germany
| | - Vivian Ludwig
- Department II of Internal Medicine; Center for Molecular Medicine Cologne (CMMC), University of Cologne, Faculty of Medicine and University Hospital Cologne, Cologne, Germany
| | - David Unnersjö Jess
- Department II of Internal Medicine; Center for Molecular Medicine Cologne (CMMC), University of Cologne, Faculty of Medicine and University Hospital Cologne, Cologne, Germany
| | - Martin Höhne
- Department II of Internal Medicine; Center for Molecular Medicine Cologne (CMMC), University of Cologne, Faculty of Medicine and University Hospital Cologne, Cologne, Germany; Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD), University of Cologne, Cologne, Germany
| | - Christian Jüngst
- Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD), University of Cologne, Cologne, Germany
| | - Ferdi Grawe
- Center for Molecular Medicine Cologne (CMMC), University of Cologne, Faculty of Medicine and University Hospital Cologne, Cologne, Germany; Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD), University of Cologne, Cologne, Germany; Molecular Cell Biology, Institute I for Anatomy, University of Cologne, Faculty of Medicine and University Hospital Cologne, Cologne, Germany
| | - Martin Helmstädter
- Renal Division, Department of Medicine, Faculty of Medicine and Medical Center, University of Freiburg, Freiburg, Germany
| | - Johanna L Janku
- Department II of Internal Medicine; Center for Molecular Medicine Cologne (CMMC), University of Cologne, Faculty of Medicine and University Hospital Cologne, Cologne, Germany
| | - Carsten Bergmann
- Medizinische Genetik Mainz, Limbach Genetics, Mainz, Germany; Department of Medicine, Nephrology, University Hospital Freiburg, Germany
| | - Peter F Hoyer
- Klinik für Kinderheilkunde 2, Zentrum für Kinder- und Jugendmedizin, Universitätsklinikum Essen, Essen, Germany
| | - H H Henning Hagmann
- Department II of Internal Medicine; Center for Molecular Medicine Cologne (CMMC), University of Cologne, Faculty of Medicine and University Hospital Cologne, Cologne, Germany
| | - Gerd Walz
- Renal Division, Department of Medicine, Faculty of Medicine and Medical Center, University of Freiburg, Freiburg, Germany
| | - Wilhelm Bloch
- Department of Molecular and Cellular Sport Medicine, Institute of Cardiovascular Research and Sport Medicine, German Sport University Cologne, Cologne, Germany
| | - Carien Niessen
- Center for Molecular Medicine Cologne (CMMC), University of Cologne, Faculty of Medicine and University Hospital Cologne, Cologne, Germany; Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD), University of Cologne, Cologne, Germany; Department of Dermatology, University Hospital of Cologne, Cologne, Germany
| | - Bernhard Schermer
- Department II of Internal Medicine; Center for Molecular Medicine Cologne (CMMC), University of Cologne, Faculty of Medicine and University Hospital Cologne, Cologne, Germany; Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD), University of Cologne, Cologne, Germany
| | - Andreas Wodarz
- Center for Molecular Medicine Cologne (CMMC), University of Cologne, Faculty of Medicine and University Hospital Cologne, Cologne, Germany; Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD), University of Cologne, Cologne, Germany; Molecular Cell Biology, Institute I for Anatomy, University of Cologne, Faculty of Medicine and University Hospital Cologne, Cologne, Germany
| | - Barry Denholm
- Biomedical Sciences, University of Edinburgh, Edinburgh, Scotland, UK
| | - Thomas Benzing
- Department II of Internal Medicine; Center for Molecular Medicine Cologne (CMMC), University of Cologne, Faculty of Medicine and University Hospital Cologne, Cologne, Germany; Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD), University of Cologne, Cologne, Germany
| | - Sandra Iden
- Center for Molecular Medicine Cologne (CMMC), University of Cologne, Faculty of Medicine and University Hospital Cologne, Cologne, Germany; Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD), University of Cologne, Cologne, Germany; Institute for Cell and Developmental Biology, Saarland University, Homburg/Saar, Germany
| | - Paul T Brinkkoetter
- Department II of Internal Medicine; Center for Molecular Medicine Cologne (CMMC), University of Cologne, Faculty of Medicine and University Hospital Cologne, Cologne, Germany.
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15
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Wang Y, Niu A, Pan Y, Cao S, Terker AS, Wang S, Fan X, Toth CL, Ramirez Solano MA, Michell DL, Contreras D, Allen RM, Zhu W, Sheng Q, Fogo AB, Vickers KC, Zhang MZ, Harris RC. Profile of Podocyte Translatome During Development of Type 2 and Type 1 Diabetic Nephropathy Using Podocyte-Specific TRAP mRNA RNA-seq. Diabetes 2021; 70:2377-2390. [PMID: 34233930 PMCID: PMC8576501 DOI: 10.2337/db21-0110] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/08/2021] [Accepted: 06/29/2021] [Indexed: 12/22/2022]
Abstract
Podocyte injury is important in development of diabetic nephropathy (DN). Although several studies have reported single-cell-based RNA sequencing (RNA-seq) of podocytes in type 1 DN (T1DN), the podocyte translating mRNA profile in type 2 DN (T2DN) has not previously been compared with that of T1DN. We analyzed the podocyte translatome in T2DN in podocin-Cre; Rosa26fsTRAP; eNOS-/-; db/db mice and compared it with that of streptozotocin-induced T1DN in podocin-Cre; Rosa26fsTRAP; eNOS-/- mice using translating ribosome affinity purification (TRAP) and RNA-seq. More than 125 genes were highly enriched in the podocyte ribosome. More podocyte TRAP genes were differentially expressed in T2DN than in T1DN. TGF-β signaling pathway genes were upregulated, while MAPK pathway genes were downregulated only in T2DN, while ATP binding and cAMP-mediated signaling genes were downregulated only in T1DN. Genes regulating actin filament organization and apoptosis increased, while genes regulating VEGFR signaling and glomerular basement membrane components decreased in both type 1 and type 2 diabetic podocytes. A number of diabetes-induced genes not previously linked to podocyte injury were confirmed in both mouse and human DN. On the basis of differences and similarities in the podocyte translatome in T2DN and T1DN, investigators can identify factors underlying the pathophysiology of DN and novel therapeutic targets to treat diabetes-induced podocyte injury.
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MESH Headings
- Animals
- Diabetes Mellitus, Experimental/genetics
- Diabetes Mellitus, Experimental/metabolism
- Diabetes Mellitus, Experimental/pathology
- Diabetes Mellitus, Type 1/complications
- Diabetes Mellitus, Type 1/genetics
- Diabetes Mellitus, Type 1/metabolism
- Diabetes Mellitus, Type 2/complications
- Diabetes Mellitus, Type 2/genetics
- Diabetes Mellitus, Type 2/metabolism
- Diabetic Nephropathies/genetics
- Diabetic Nephropathies/metabolism
- Diabetic Nephropathies/pathology
- Gene Expression Profiling
- Male
- Mice
- Mice, Inbred C57BL
- Mice, Knockout
- Organ Specificity/genetics
- Podocytes/metabolism
- Podocytes/pathology
- Protein Biosynthesis/genetics
- Proteome/analysis
- Proteome/genetics
- Proteome/metabolism
- RNA, Messenger/analysis
- RNA, Messenger/genetics
- RNA, Messenger/metabolism
- RNA-Seq
- Sequence Analysis, RNA
- Streptozocin
- Transcriptome
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Affiliation(s)
- Yinqiu Wang
- Division of Nephrology and Hypertension, Vanderbilt University School of Medicine, Nashville, TN
- Vanderbilt Center for Kidney Disease, Vanderbilt University School of Medicine, Nashville, TN
| | - Aolei Niu
- Division of Nephrology and Hypertension, Vanderbilt University School of Medicine, Nashville, TN
- Vanderbilt Center for Kidney Disease, Vanderbilt University School of Medicine, Nashville, TN
| | - Yu Pan
- Division of Nephrology and Hypertension, Vanderbilt University School of Medicine, Nashville, TN
- Vanderbilt Center for Kidney Disease, Vanderbilt University School of Medicine, Nashville, TN
| | - Shirong Cao
- Division of Nephrology and Hypertension, Vanderbilt University School of Medicine, Nashville, TN
- Vanderbilt Center for Kidney Disease, Vanderbilt University School of Medicine, Nashville, TN
| | - Andrew S Terker
- Division of Nephrology and Hypertension, Vanderbilt University School of Medicine, Nashville, TN
- Vanderbilt Center for Kidney Disease, Vanderbilt University School of Medicine, Nashville, TN
| | - Suwan Wang
- Division of Nephrology and Hypertension, Vanderbilt University School of Medicine, Nashville, TN
- Vanderbilt Center for Kidney Disease, Vanderbilt University School of Medicine, Nashville, TN
| | - Xiaofeng Fan
- Division of Nephrology and Hypertension, Vanderbilt University School of Medicine, Nashville, TN
- Vanderbilt Center for Kidney Disease, Vanderbilt University School of Medicine, Nashville, TN
| | - Cynthia L Toth
- Division of Cardiovascular Medicine, Department of Medicine, Vanderbilt University School of Medicine, Nashville, TN
| | - Marisol A Ramirez Solano
- Division of Cardiovascular Medicine, Department of Medicine, Vanderbilt University School of Medicine, Nashville, TN
| | - Danielle L Michell
- Division of Cardiovascular Medicine, Department of Medicine, Vanderbilt University School of Medicine, Nashville, TN
| | - Danielle Contreras
- Division of Cardiovascular Medicine, Department of Medicine, Vanderbilt University School of Medicine, Nashville, TN
| | - Ryan M Allen
- Division of Cardiovascular Medicine, Department of Medicine, Vanderbilt University School of Medicine, Nashville, TN
| | - Wanying Zhu
- Division of Cardiovascular Medicine, Department of Medicine, Vanderbilt University School of Medicine, Nashville, TN
| | - Quanhu Sheng
- Division of Cardiovascular Medicine, Department of Medicine, Vanderbilt University School of Medicine, Nashville, TN
| | - Agnes B Fogo
- Division of Nephrology and Hypertension, Vanderbilt University School of Medicine, Nashville, TN
- Department of Pathology, Microbiology and Immunology, Vanderbilt University School of Medicine, Nashville, TN
| | - Kasey C Vickers
- Division of Cardiovascular Medicine, Department of Medicine, Vanderbilt University School of Medicine, Nashville, TN
| | - Ming-Zhi Zhang
- Division of Nephrology and Hypertension, Vanderbilt University School of Medicine, Nashville, TN
- Vanderbilt Center for Kidney Disease, Vanderbilt University School of Medicine, Nashville, TN
| | - Raymond C Harris
- Division of Nephrology and Hypertension, Vanderbilt University School of Medicine, Nashville, TN
- Vanderbilt Center for Kidney Disease, Vanderbilt University School of Medicine, Nashville, TN
- Department of Veterans Affairs, Nashville, TN
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16
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PPARγ and TGFβ-Major Regulators of Metabolism, Inflammation, and Fibrosis in the Lungs and Kidneys. Int J Mol Sci 2021; 22:ijms221910431. [PMID: 34638771 PMCID: PMC8508998 DOI: 10.3390/ijms221910431] [Citation(s) in RCA: 50] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2021] [Revised: 09/24/2021] [Accepted: 09/24/2021] [Indexed: 01/06/2023] Open
Abstract
Peroxisome proliferator-activated receptor gamma (PPARγ) is a type II nuclear receptor, initially recognized in adipose tissue for its role in fatty acid storage and glucose metabolism. It promotes lipid uptake and adipogenesis by increasing insulin sensitivity and adiponectin release. Later, PPARγ was implicated in cardiac development and in critical conditions such as pulmonary arterial hypertension (PAH) and kidney failure. Recently, a cluster of different papers linked PPARγ signaling with another superfamily, the transforming growth factor beta (TGFβ), and its receptors, all of which play a major role in PAH and kidney failure. TGFβ is a multifunctional cytokine that drives inflammation, fibrosis, and cell differentiation while PPARγ activation reverses these adverse events in many models. Such opposite biological effects emphasize the delicate balance and complex crosstalk between PPARγ and TGFβ. Based on solid experimental and clinical evidence, the present review summarizes connections and their implications for PAH and kidney failure, highlighting the similarities and differences between lung and kidney mechanisms as well as discussing the therapeutic potential of PPARγ agonist pioglitazone.
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17
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Hatje FA, Wedekind U, Sachs W, Loreth D, Reichelt J, Demir F, Kosub C, Heintz L, Tomas NM, Huber TB, Skuza S, Sachs M, Zielinski S, Rinschen MM, Meyer-Schwesinger C. Tripartite Separation of Glomerular Cell Types and Proteomes from Reporter-Free Mice. J Am Soc Nephrol 2021; 32:2175-2193. [PMID: 34074698 PMCID: PMC8729851 DOI: 10.1681/asn.2020091346] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2020] [Accepted: 04/09/2021] [Indexed: 02/04/2023] Open
Abstract
BACKGROUND The glomerulus comprises podocytes, mesangial cells, and endothelial cells, which jointly determine glomerular filtration. Understanding this intricate functional unit beyond the transcriptome requires bulk isolation of these cell types for biochemical investigations. We developed a globally applicable tripartite isolation method for murine mesangial and endothelial cells and podocytes (timMEP). METHODS We separated glomerular cell types from wild-type or mT/mG mice via a novel FACS approach, and validated their purity. Cell type proteomes were compared between strains, ages, and sex. We applied timMEP to the podocyte-targeting, immunologic, THSD7A-associated, model of membranous nephropathy. RESULTS timMEP enabled protein-biochemical analyses of podocytes, mesangial cells, and endothelial cells derived from reporter-free mice, and allowed for the characterization of podocyte, endothelial, and mesangial proteomes of individual mice. We identified marker proteins for mesangial and endothelial proteins, and outlined protein-based, potential communication networks and phosphorylation patterns. The analysis detected cell type-specific proteome differences between mouse strains and alterations depending on sex, age, and transgene. After exposure to anti-THSD7A antibodies, timMEP resolved a fine-tuned initial stress response, chiefly in podocytes, that could not be detected by bulk glomerular analyses. The combination of proteomics with super-resolution imaging revealed a specific loss of slit diaphragm, but not of other foot process proteins, unraveling a protein-based mechanism of podocyte injury in this animal model. CONCLUSION timMEP enables glomerular cell type-resolved investigations at the transcriptional and protein-biochemical level in health and disease, while avoiding reporter-based artifacts, paving the way toward the comprehensive and systematic characterization of glomerular cell biology.
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Affiliation(s)
- Favian A. Hatje
- Institute of Cellular and Integrative Physiology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Uta Wedekind
- Institute of Cellular and Integrative Physiology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Wiebke Sachs
- Institute of Cellular and Integrative Physiology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Desiree Loreth
- Institute of Cellular and Integrative Physiology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Julia Reichelt
- Institute of Cellular and Integrative Physiology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Fatih Demir
- Department of Biomedicine, Aarhus University, Aarhus, Denmark
| | - Christopher Kosub
- Institute of Cellular and Integrative Physiology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Lukas Heintz
- Institute of Cellular and Integrative Physiology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Nicola M. Tomas
- III Department of Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Tobias B. Huber
- III Department of Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Sinah Skuza
- Institute of Cellular and Integrative Physiology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Marlies Sachs
- Institute of Cellular and Integrative Physiology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Stephanie Zielinski
- Institute of Cellular and Integrative Physiology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Markus M. Rinschen
- Department of Biomedicine, Aarhus University, Aarhus, Denmark
- III Department of Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
- Department II of Internal Medicine, Center for Molecular Medicine Cologne, University of Cologne, Cologne, Germany
| | - Catherine Meyer-Schwesinger
- Institute of Cellular and Integrative Physiology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
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18
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Korin B, Chung JJ, Avraham S, Shaw AS. Preparation of single-cell suspensions of mouse glomeruli for high-throughput analysis. Nat Protoc 2021; 16:4068-4083. [PMID: 34282333 DOI: 10.1038/s41596-021-00578-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2020] [Accepted: 05/27/2021] [Indexed: 02/06/2023]
Abstract
The kidney glomerulus is essential for proper kidney function. Until recently, technical challenges associated with glomerular isolation and subsequent dissolution into single cells have limited the detailed characterization of cells in the glomerulus. Previous techniques of kidney dissociation result in low glomerular cell yield, which limits high-throughput analysis. The ability to efficiently purify glomeruli and digest the tissue into single cells is especially important for single-cell characterization methods. Here, we present a detailed and comprehensive technique for the extraction and preparation of mouse glomerular cells, with high yield and viability. The method includes direct renal perfusion of Dynabeads via the renal artery followed by kidney dissociation and isolation of glomeruli by magnet; these steps provide a high number and purity of isolated glomeruli, which are further dissociated into single cells. The balanced representation of podocytes, mesangial and endothelial cells in single-cell suspensions of mouse glomeruli, and the high cell viability observed, confirm the efficiency of our method. With some practice, the procedure can be done in <3 h (excluding equipment setup and data analysis). This protocol provides a valuable technique for advancing future single-cell-based studies of the glomerulus in health, injury and disease.
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Affiliation(s)
- Ben Korin
- Department of Research Biology, Genentech, South San Francisco, CA, USA
| | - Jun-Jae Chung
- Department of Research Biology, Genentech, South San Francisco, CA, USA
| | - Shimrit Avraham
- Department of Research Biology, Genentech, South San Francisco, CA, USA
| | - Andrey S Shaw
- Department of Research Biology, Genentech, South San Francisco, CA, USA.
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19
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Fu J, Yi Z, Cai M, Yuan W, Zhang W, Lee K, He JC. Global transcriptomic changes in glomerular endothelial cells in mice with podocyte depletion and glomerulosclerosis. Cell Death Dis 2021; 12:687. [PMID: 34244474 PMCID: PMC8270962 DOI: 10.1038/s41419-021-03951-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2020] [Revised: 06/03/2021] [Accepted: 06/08/2021] [Indexed: 02/06/2023]
Abstract
Podocytes are a key component of the glomerular filtration barrier, and its dysfunction and eventual loss drive glomerular disease progression. Recent research has demonstrated the importance of podocyte cross-talk with other glomerular cells, such as glomerular endothelial cells (GECs), in both glomerular homeostasis and in disease settings. However, how GECs are affected globally by podocyte injury and loss in disease settings remains unclear. Therefore, to characterize the molecular changes occurring in GECs in response to the podocyte loss, we performed the transcriptomic profiling of isolated GECs after diphtheria toxin (DT)-mediated podocyte depletion in transgenic mice with podocyte-specific human DT receptor and endothelial-specific enhanced yellow fluorescent protein (EYFP) expression. DT administration led to nearly 40% of podocyte loss with the development of glomerulosclerosis. Differential gene expression analysis of isolated GECs in the diseased mice showed significant changes in pathways related to cell adhesion and actin cytoskeleton, proliferation, and angiogenesis, as well as apoptosis and cell death. However, quantification of EYFP + GECs indicated that there was a reduction in GECs in the diseased mice, suggesting that despite the ongoing proliferation, the concomitant injury and the activation of cell death program results in their overall net loss. The upstream regulator analysis strongly indicated the involvement of p53, TGF-β1, and TNF-α as key mediators of the molecular changes occurring in GECs in the diseased mice. Our findings demonstrate significant molecular changes in GECs as a secondary consequence of podocyte loss and provide a valuable resource for further in-depth analysis of potential glomerular cross-talk mediators.
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Affiliation(s)
- Jia Fu
- Division of Nephrology, Department of Medicine, Icahn School of Medicine at Mount Sinai, New York, NY, USA.
| | - Zhengzi Yi
- Division of Nephrology, Department of Medicine, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Minchao Cai
- Department of Nephrology, Shanghai General Hospital, Shanghai Jiao Tong University, Shanghai, China
| | - Weijie Yuan
- Department of Nephrology, Shanghai General Hospital, Shanghai Jiao Tong University, Shanghai, China
| | - Weijia Zhang
- Division of Nephrology, Department of Medicine, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Kyung Lee
- Division of Nephrology, Department of Medicine, Icahn School of Medicine at Mount Sinai, New York, NY, USA.
| | - John Cijiang He
- Division of Nephrology, Department of Medicine, Icahn School of Medicine at Mount Sinai, New York, NY, USA.
- Renal Program, James J. Peters Veterans Affairs Medical Center at Bronx, New York, NY, USA.
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20
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Yang J, Zhang D, Motojima M, Kume T, Hou Q, Pan Y, Duan A, Zhang M, Jiang S, Hou J, Shi J, Qin Z, Liu Z. Super-Enhancer-Associated Transcription Factors Maintain Transcriptional Regulation in Mature Podocytes. J Am Soc Nephrol 2021; 32:1323-1337. [PMID: 33771836 PMCID: PMC8259645 DOI: 10.1681/asn.2020081177] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2020] [Accepted: 01/30/2021] [Indexed: 02/04/2023] Open
Abstract
BACKGROUND Transcriptional programs control cell fate, and identifying their components is critical for understanding diseases caused by cell lesion, such as podocytopathy. Although many transcription factors (TFs) are necessary for cell-state maintenance in glomeruli, their roles in transcriptional regulation are not well understood. METHODS The distribution of H3K27ac histones in human glomerulus cells was analyzed to identify superenhancer-associated TFs, and ChIP-seq and transcriptomics were performed to elucidate the regulatory roles of the TFs. Transgenic animal models of disease were further investigated to confirm the roles of specific TFs in podocyte maintenance. RESULTS Superenhancer distribution revealed a group of potential TFs in core regulatory circuits in human glomerulus cells, including FOXC1/2, WT1, and LMX1B. Integration of transcriptome and cistrome data of FOXC1/2 in mice resolved transcriptional regulation in podocyte maintenance. FOXC1/2 regulated differentiation-associated transcription in mature podocytes. In both humans and animal models, mature podocyte injury was accompanied by deregulation of FOXC1/2 expression, and FOXC1/2 overexpression could protect podocytes in zebrafish. CONCLUSIONS FOXC1/2 maintain podocyte differentiation through transcriptional stabilization. The genome-wide chromatin resources support further investigation of TFs' regulatory roles in glomeruli transcription programs.
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Affiliation(s)
- Jingping Yang
- Medical School of Nanjing University, Nanjing, China
- National Clinical Research Center of Kidney Diseases, Jinling Hospital, Medical School of Nanjing University, Nanjing, China
| | - Difei Zhang
- National Clinical Research Center of Kidney Diseases, Jinling Hospital, Medical School of Nanjing University, Nanjing, China
| | - Masaru Motojima
- Department of Clinical Pharmacology, Tokai University School of Medicine, Isehara, Japan
| | - Tsutomu Kume
- Feinberg Cardiovascular Research Institute, Feinberg School of Medicine, Northwestern University, Chicago, Illinois
| | - Qing Hou
- National Clinical Research Center of Kidney Diseases, Jinling Hospital, Medical School of Nanjing University, Nanjing, China
| | - Yu Pan
- National Clinical Research Center of Kidney Diseases, Jinling Hospital, Medical School of Nanjing University, Nanjing, China
| | - Aiping Duan
- National Clinical Research Center of Kidney Diseases, Jinling Hospital, Medical School of Nanjing University, Nanjing, China
| | - Mingchao Zhang
- National Clinical Research Center of Kidney Diseases, Jinling Hospital, Medical School of Nanjing University, Nanjing, China
| | - Song Jiang
- National Clinical Research Center of Kidney Diseases, Jinling Hospital, Medical School of Nanjing University, Nanjing, China
| | - Jinhua Hou
- National Clinical Research Center of Kidney Diseases, Jinling Hospital, Medical School of Nanjing University, Nanjing, China
| | - Jingsong Shi
- National Clinical Research Center of Kidney Diseases, Jinling Hospital, Medical School of Nanjing University, Nanjing, China
| | - Zhaohui Qin
- Department of Biostatistics and Bioinformatics, Rollins School of Public Health, Emory University, Atlanta, Georgia
| | - Zhihong Liu
- Medical School of Nanjing University, Nanjing, China
- National Clinical Research Center of Kidney Diseases, Jinling Hospital, Medical School of Nanjing University, Nanjing, China
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21
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Abstract
The identification of the phospholipase A2 receptor 1 (PLA2R) and thrombospondin type-1 domain-containing protein 7A (THSD7A) as podocyte antigens in adult patients with membranous nephropathy (MN) has strongly impacted both experimental and clinical research on this disease. Evidence has been furnished that podocyte-directed autoantibodies can cause MN, and novel PLA2R- and THSD7A-specific animal models have been developed. Today, measurement of serum autoantibody levels and staining of kidney biopsies for the target antigens guides MN diagnosis and treatment worldwide. Additionally, anti-PLA2R antibodies have been proven to be valuable prognostic biomarkers in MN. Despite these impressive advances, a variety of questions regarding the disease pathomechanisms, clinical use of antibody measurement, and future treatments remain unanswered. In this review, we will outline recent advances made in the field of MN and discuss open questions and perspectives with a focus on novel antigen identification, mechanisms of podocyte injury, clinical use of antibody measurement to guide diagnosis and treatment, and the potential of innovative, pathogenesis-based treatment strategies.
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22
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Mechanisms of Primary Membranous Nephropathy. Biomolecules 2021; 11:biom11040513. [PMID: 33808418 PMCID: PMC8065962 DOI: 10.3390/biom11040513] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2021] [Revised: 03/23/2021] [Accepted: 03/26/2021] [Indexed: 12/11/2022] Open
Abstract
Membranous nephropathy (MN) is an autoimmune disease of the kidney glomerulus and one of the leading causes of nephrotic syndrome. The disease exhibits heterogenous outcomes with approximately 30% of cases progressing to end-stage renal disease. The clinical management of MN has steadily advanced owing to the identification of autoantibodies to the phospholipase A2 receptor (PLA2R) in 2009 and thrombospondin domain-containing 7A (THSD7A) in 2014 on the podocyte surface. Approximately 50–80% and 3–5% of primary MN (PMN) cases are associated with either anti-PLA2R or anti-THSD7A antibodies, respectively. The presence of these autoantibodies is used for MN diagnosis; antibody levels correlate with disease severity and possess significant biomarker values in monitoring disease progression and treatment response. Importantly, both autoantibodies are causative to MN. Additionally, evidence is emerging that NELL-1 is associated with 5–10% of PMN cases that are PLA2R- and THSD7A-negative, which moves us one step closer to mapping out the full spectrum of PMN antigens. Recent developments suggest exostosin 1 (EXT1), EXT2, NELL-1, and contactin 1 (CNTN1) are associated with MN. Genetic factors and other mechanisms are in place to regulate these factors and may contribute to MN pathogenesis. This review will discuss recent developments over the past 5 years.
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23
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Talyan S, Filipów S, Ignarski M, Smieszek M, Chen H, Kühne L, Butt L, Göbel H, Hoyer-Allo KJR, Koehler FC, Altmüller J, Brinkkötter P, Schermer B, Benzing T, Kann M, Müller RU, Dieterich C. CALINCA-A Novel Pipeline for the Identification of lncRNAs in Podocyte Disease. Cells 2021; 10:692. [PMID: 33804736 PMCID: PMC8003990 DOI: 10.3390/cells10030692] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2021] [Revised: 03/13/2021] [Accepted: 03/15/2021] [Indexed: 11/16/2022] Open
Abstract
Diseases of the renal filtration unit-the glomerulus-are the most common cause of chronic kidney disease. Podocytes are the pivotal cell type for the function of this filter and focal-segmental glomerulosclerosis (FSGS) is a classic example of a podocytopathy leading to proteinuria and glomerular scarring. Currently, no targeted treatment of FSGS is available. This lack of therapeutic strategies is explained by a limited understanding of the defects in podocyte cell biology leading to FSGS. To date, most studies in the field have focused on protein-coding genes and their gene products. However, more than 80% of all transcripts produced by mammalian cells are actually non-coding. Here, long non-coding RNAs (lncRNAs) are a relatively novel class of transcripts and have not been systematically studied in FSGS to date. The appropriate tools to facilitate lncRNA research for the renal scientific community are urgently required due to a row of challenges compared to classical analysis pipelines optimized for coding RNA expression analysis. Here, we present the bioinformatic pipeline CALINCA as a solution for this problem. CALINCA automatically analyzes datasets from murine FSGS models and quantifies both annotated and de novo assembled lncRNAs. In addition, the tool provides in-depth information on podocyte specificity of these lncRNAs, as well as evolutionary conservation and expression in human datasets making this pipeline a crucial basis to lncRNA studies in FSGS.
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Affiliation(s)
- Sweta Talyan
- German Center for Cardiovascular Research (DZHK), Partner Site Heidelberg/Mannheim, Im Neuenheimer Feld 669, 69120 Heidelberg, Germany;
- Section of Bioinformatics and Systems Cardiology, Klaus Tschira Institute for Integrative Computational Cardiology and Department of Internal Medicine III, Im Neuenheimer Feld 669, 69120 Heidelberg, Germany;
| | - Samantha Filipów
- Department II of Internal Medicine and Center for Molecular Medicine, University of Cologne, Faculty of Medicine and University Hospital Cologne, 50931 Cologne, Germany; (S.F.); (M.I.); (H.C.); (L.K.); (L.B.); (K.J.R.H.-A.); (F.C.K.); (P.B.); (B.S.); (T.B.); (M.K.)
- Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD), University of Cologne, 50931 Cologne, Germany
| | - Michael Ignarski
- Department II of Internal Medicine and Center for Molecular Medicine, University of Cologne, Faculty of Medicine and University Hospital Cologne, 50931 Cologne, Germany; (S.F.); (M.I.); (H.C.); (L.K.); (L.B.); (K.J.R.H.-A.); (F.C.K.); (P.B.); (B.S.); (T.B.); (M.K.)
- Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD), University of Cologne, 50931 Cologne, Germany
| | - Magdalena Smieszek
- Section of Bioinformatics and Systems Cardiology, Klaus Tschira Institute for Integrative Computational Cardiology and Department of Internal Medicine III, Im Neuenheimer Feld 669, 69120 Heidelberg, Germany;
| | - He Chen
- Department II of Internal Medicine and Center for Molecular Medicine, University of Cologne, Faculty of Medicine and University Hospital Cologne, 50931 Cologne, Germany; (S.F.); (M.I.); (H.C.); (L.K.); (L.B.); (K.J.R.H.-A.); (F.C.K.); (P.B.); (B.S.); (T.B.); (M.K.)
- Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD), University of Cologne, 50931 Cologne, Germany
| | - Lucas Kühne
- Department II of Internal Medicine and Center for Molecular Medicine, University of Cologne, Faculty of Medicine and University Hospital Cologne, 50931 Cologne, Germany; (S.F.); (M.I.); (H.C.); (L.K.); (L.B.); (K.J.R.H.-A.); (F.C.K.); (P.B.); (B.S.); (T.B.); (M.K.)
- Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD), University of Cologne, 50931 Cologne, Germany
| | - Linus Butt
- Department II of Internal Medicine and Center for Molecular Medicine, University of Cologne, Faculty of Medicine and University Hospital Cologne, 50931 Cologne, Germany; (S.F.); (M.I.); (H.C.); (L.K.); (L.B.); (K.J.R.H.-A.); (F.C.K.); (P.B.); (B.S.); (T.B.); (M.K.)
- Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD), University of Cologne, 50931 Cologne, Germany
| | - Heike Göbel
- Institute for Pathology, Diagnostic and Experimental Nephropathology Unit, University of Cologne, Faculty of Medicine and University Hospital Cologne, 50931 Cologne, Germany;
| | - K. Johanna R. Hoyer-Allo
- Department II of Internal Medicine and Center for Molecular Medicine, University of Cologne, Faculty of Medicine and University Hospital Cologne, 50931 Cologne, Germany; (S.F.); (M.I.); (H.C.); (L.K.); (L.B.); (K.J.R.H.-A.); (F.C.K.); (P.B.); (B.S.); (T.B.); (M.K.)
- Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD), University of Cologne, 50931 Cologne, Germany
| | - Felix C. Koehler
- Department II of Internal Medicine and Center for Molecular Medicine, University of Cologne, Faculty of Medicine and University Hospital Cologne, 50931 Cologne, Germany; (S.F.); (M.I.); (H.C.); (L.K.); (L.B.); (K.J.R.H.-A.); (F.C.K.); (P.B.); (B.S.); (T.B.); (M.K.)
- Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD), University of Cologne, 50931 Cologne, Germany
| | - Janine Altmüller
- Cologne Center for Genomics, University of Cologne, 50931 Cologne, Germany;
| | - Paul Brinkkötter
- Department II of Internal Medicine and Center for Molecular Medicine, University of Cologne, Faculty of Medicine and University Hospital Cologne, 50931 Cologne, Germany; (S.F.); (M.I.); (H.C.); (L.K.); (L.B.); (K.J.R.H.-A.); (F.C.K.); (P.B.); (B.S.); (T.B.); (M.K.)
- Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD), University of Cologne, 50931 Cologne, Germany
| | - Bernhard Schermer
- Department II of Internal Medicine and Center for Molecular Medicine, University of Cologne, Faculty of Medicine and University Hospital Cologne, 50931 Cologne, Germany; (S.F.); (M.I.); (H.C.); (L.K.); (L.B.); (K.J.R.H.-A.); (F.C.K.); (P.B.); (B.S.); (T.B.); (M.K.)
- Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD), University of Cologne, 50931 Cologne, Germany
| | - Thomas Benzing
- Department II of Internal Medicine and Center for Molecular Medicine, University of Cologne, Faculty of Medicine and University Hospital Cologne, 50931 Cologne, Germany; (S.F.); (M.I.); (H.C.); (L.K.); (L.B.); (K.J.R.H.-A.); (F.C.K.); (P.B.); (B.S.); (T.B.); (M.K.)
- Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD), University of Cologne, 50931 Cologne, Germany
| | - Martin Kann
- Department II of Internal Medicine and Center for Molecular Medicine, University of Cologne, Faculty of Medicine and University Hospital Cologne, 50931 Cologne, Germany; (S.F.); (M.I.); (H.C.); (L.K.); (L.B.); (K.J.R.H.-A.); (F.C.K.); (P.B.); (B.S.); (T.B.); (M.K.)
- Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD), University of Cologne, 50931 Cologne, Germany
| | - Roman-Ulrich Müller
- Department II of Internal Medicine and Center for Molecular Medicine, University of Cologne, Faculty of Medicine and University Hospital Cologne, 50931 Cologne, Germany; (S.F.); (M.I.); (H.C.); (L.K.); (L.B.); (K.J.R.H.-A.); (F.C.K.); (P.B.); (B.S.); (T.B.); (M.K.)
- Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD), University of Cologne, 50931 Cologne, Germany
| | - Christoph Dieterich
- German Center for Cardiovascular Research (DZHK), Partner Site Heidelberg/Mannheim, Im Neuenheimer Feld 669, 69120 Heidelberg, Germany;
- Section of Bioinformatics and Systems Cardiology, Klaus Tschira Institute for Integrative Computational Cardiology and Department of Internal Medicine III, Im Neuenheimer Feld 669, 69120 Heidelberg, Germany;
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24
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Okabe M, Yamamoto K, Miyazaki Y, Motojima M, Ohtsuka M, Pastan I, Yokoo T, Matsusaka T. Indirect podocyte injury manifested in a partial podocytectomy mouse model. Am J Physiol Renal Physiol 2021; 320:F922-F933. [PMID: 33719575 DOI: 10.1152/ajprenal.00602.2020] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
In progressive glomerular diseases, segmental podocyte injury often expands, leading to global glomerulosclerosis by unclear mechanisms. To study the expansion of podocyte injury, we established a new mosaic mouse model in which a fraction of podocytes express human (h)CD25 and can be injured by the immunotoxin LMB2. hCD25+ and hCD25- podocytes were designed to express tdTomato and enhanced green fluorescent protein (EGFP), respectively, which enabled cell sorting analysis of podocytes. After the injection of LMB2, mosaic mice developed proteinuria and glomerulosclerosis. Not only tdTomato+ podocytes but also EGFP+ podocytes were decreased in number and showed damage, as evidenced by a decrease in nephrin and an increase in desmin at both protein and RNA levels. Transcriptomics analysis found a decrease in the glucocorticoid-induced transcript 1 gene and an increase in the thrombospondin 4, heparin-binding EGF-like growth factor, and transforming growth factor-β genes in EGFP+ podocytes; these genes may be candidate mediators of secondary podocyte damage. Pathway analysis suggested that focal adhesion, integrin-mediated cell adhesion, and focal adhesion-phosphatidylinositol 3-kinase-Akt-mammalian target of rapamycin signaling are involved in secondary podocyte injury. Finally, treatment of mosaic mice with angiotensin II receptor blocker markedly ameliorated secondary podocyte injury. This mosaic podocyte injury model has distinctly demonstrated that damaged podocytes cause secondary podocyte damage, which may be a promising therapeutic target in progressive kidney diseases.NEW & NOTEWORTHY This novel mosaic model has demonstrated that when a fraction of podocytes is injured, other podocytes are subjected to secondary injury. This spreading of injury may occur ubiquitously irrespective of the primary cause of podocyte injury, leading to end-stage renal failure. Understanding the molecular mechanism of secondary podocyte injury and its prevention is important for the treatment of progressive kidney diseases. This model will be a powerful tool for studying the indirect podocyte injury.
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Affiliation(s)
- Masahiro Okabe
- Division of Nephrology and Hypertension, Department of Internal Medicine, Jikei University School of Medicine, Tokyo, Japan.,Department of Basic Medicine, Tokai University School of Medicine, Isehara, Japan
| | - Kazuyoshi Yamamoto
- Division of Nephrology and Hypertension, Department of Internal Medicine, Jikei University School of Medicine, Tokyo, Japan.,Department of Basic Medicine, Tokai University School of Medicine, Isehara, Japan
| | - Yoichi Miyazaki
- Division of Nephrology and Hypertension, Department of Internal Medicine, Jikei University School of Medicine, Tokyo, Japan
| | - Masaru Motojima
- Department of Clinical Pharmacology, Tokai University School of Medicine, Isehara, Japan
| | - Masato Ohtsuka
- Department of Basic Medicine, Tokai University School of Medicine, Isehara, Japan.,Institute of Medical Science, Tokai University School of Medicine, Isehara, Japan
| | - Ira Pastan
- Laboratory of Molecular Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, Maryland
| | - Takashi Yokoo
- Division of Nephrology and Hypertension, Department of Internal Medicine, Jikei University School of Medicine, Tokyo, 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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25
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EPB41L5 controls podocyte extracellular matrix assembly by adhesome-dependent force transmission. Cell Rep 2021; 34:108883. [PMID: 33761352 DOI: 10.1016/j.celrep.2021.108883] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2020] [Revised: 12/21/2020] [Accepted: 02/25/2021] [Indexed: 12/14/2022] Open
Abstract
The integrity of the kidney filtration barrier essentially relies on the balanced interplay of podocytes and the glomerular basement membrane (GBM). Here, we show by analysis of in vitro and in vivo models that a loss of the podocyte-specific FERM-domain protein EPB41L5 results in impaired extracellular matrix (ECM) assembly. By using quantitative proteomics analysis of the secretome and matrisome, we demonstrate a shift in ECM composition characterized by diminished deposition of core GBM components, such as LAMA5. Integrin adhesome proteomics reveals that EPB41L5 recruits PDLIM5 and ACTN4 to integrin adhesion complexes (IACs). Consecutively, EPB41L5 knockout podocytes show insufficient maturation of integrin adhesion sites, which translates into impaired force transmission and ECM assembly. These observations build the framework for a model in which EPB41L5 functions as a cell-type-specific regulator of the podocyte adhesome and controls a localized adaptive module in order to prevent podocyte detachment and thereby ensures GBM integrity.
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26
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Liu L, Ma F, Hao Y, Yi Z, Yu X, Xu B, Wei C, Hu J. Integrative Informatics Analysis of Transcriptome and Identification of Interacted Genes in the Glomeruli and Tubules in CKD. Front Med (Lausanne) 2021; 7:615306. [PMID: 33644086 PMCID: PMC7906987 DOI: 10.3389/fmed.2020.615306] [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: 10/08/2020] [Accepted: 12/23/2020] [Indexed: 11/16/2022] Open
Abstract
Chronic kidney disease (CKD) is a complex disease in which the renal function is compromised chronically. Many studies have indicated the crosstalk between the tubule and the glomerulus in CKD progression. However, our understanding of the interaction of tubular and glomerular injury remains incomplete. In this study, we applied a meta-analysis approach on the transcriptome of the tubules and glomeruli of CKD patients to identify differentially expressed genes (DEGs) signature. Functional analysis of pathways and Gene Ontology found that tubular DEGs were mainly involved in cell assembly and remodeling, glomerular DEGs in cell proliferation and apoptosis, and overlapping DEGs mainly in immune response. Correlation analysis was performed to identify the associated DEGs in the tubules and glomeruli. Secreted protein comparison and verification experiments indicated that WFDC2 from the tubule could downregulate PEX19 mRNA and protein levels at the glomeruli in diabetic kidney disease (DKD). This study revealed the distinctive pathways of the tubules and glomeruli and identified interacted genes during CKD progression.
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Affiliation(s)
- Lingyun Liu
- Department of Andrology, The First Hospital of Jilin University, Jilin, China
| | - Fuzhe Ma
- Department of Nephrology, The First Hospital of Jilin University, Jilin, China
| | - Yuanyuan Hao
- Department of Urology, The First Hospital of Jilin University, Jilin, China
| | - Zhengzi Yi
- Division of Nephrology, Icahn School of Medicine at Mount Sinai, New York, NY, United States
| | - Xiaoxia Yu
- Division of Nephrology, Affiliated Zhongshan Hospital of Dalian University, Dalian, China
| | - Bo Xu
- Department of Urology, The First Hospital of Jilin University, Jilin, China
| | - Chengguo Wei
- Division of Nephrology, Icahn School of Medicine at Mount Sinai, New York, NY, United States
| | - Jinghai Hu
- Department of Urology, The First Hospital of Jilin University, Jilin, China
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27
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Xiao M, Bohnert BN, Aypek H, Kretz O, Grahammer F, Aukschun U, Wörn M, Janessa A, Essigke D, Daniel C, Amann K, Huber TB, Plow EF, Birkenfeld AL, Artunc F. Plasminogen deficiency does not prevent sodium retention in a genetic mouse model of experimental nephrotic syndrome. Acta Physiol (Oxf) 2021; 231:e13512. [PMID: 32455507 DOI: 10.1111/apha.13512] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2020] [Revised: 05/15/2020] [Accepted: 05/19/2020] [Indexed: 12/19/2022]
Abstract
AIM Sodium retention is the hallmark of nephrotic syndrome (NS) and mediated by the proteolytic activation of the epithelial sodium channel (ENaC) by aberrantly filtered serine proteases. Plasmin is highly abundant in nephrotic urine and has been proposed to be the principal serine protease responsible for ENaC activation in NS. However, a proof of the essential role of plasmin in experimental NS is lacking. METHODS We used a genetic mouse model of NS based on an inducible podocin knockout (Bl6-Nphs2tm3.1Antc *Tg(Nphs1-rtTA*3G)8Jhm *Tg(tetO-cre)1Jaw or nphs2Δipod ). These mice were crossed with plasminogen deficient mice (Bl6-Plgtm1Jld or plg-/- ) to generate double knockout mice (nphs2Δipod *plg-/- ). NS was induced after oral doxycycline treatment for 14 days and mice were followed for subsequent 14 days. RESULTS Uninduced nphs2Δipod *plg-/- mice had normal kidney function and sodium handling. After induction, proteinuria increased similarly in both nphs2Δipod *plg+/+ and nphs2Δipod *plg-/- mice. Western blot revealed the urinary excretion of plasminogen and plasmin in nphs2Δipod *plg+/+ mice which were absent in nphs2Δipod *plg-/- mice. After the onset of proteinuria, amiloride-sensitive natriuresis was increased compared to the uninduced state in both genotypes. Subsequently, urinary sodium excretion dropped in both genotypes leading to an increase in body weight and development of ascites. Treatment with the serine protease inhibitor aprotinin prevented sodium retention in both genotypes. CONCLUSIONS This study shows that mice lacking urinary plasminogen are not protected from ENaC-mediated sodium retention in experimental NS. This points to an essential role of other urinary serine proteases in the absence of plasminogen.
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Affiliation(s)
- Mengyun Xiao
- Department of Internal Medicine Division of Endocrinology, Diabetology and Nephrology University Hospital Tübingen Tübingen Germany
| | - Bernhard N. Bohnert
- Department of Internal Medicine Division of Endocrinology, Diabetology and Nephrology University Hospital Tübingen Tübingen Germany
- Institute of Diabetes Research and Metabolic Diseases (IDM) of the Helmholtz Center Munich at the University Tübingen Tübingen Germany
- German Center for Diabetes Research (DZD) at the University Tübingen Tübingen Germany
| | - Hande Aypek
- III. Department of Medicine University Medical Center Hamburg‐Eppendorf Hamburg Germany
| | - Oliver Kretz
- III. Department of Medicine University Medical Center Hamburg‐Eppendorf Hamburg Germany
| | - Florian Grahammer
- III. Department of Medicine University Medical Center Hamburg‐Eppendorf Hamburg Germany
| | - Ute Aukschun
- IV. Department of Medicine, Faculty and University Medical Center Freiburg Freiburg Germany
| | - Matthias Wörn
- Department of Internal Medicine Division of Endocrinology, Diabetology and Nephrology University Hospital Tübingen Tübingen Germany
| | - Andrea Janessa
- Department of Internal Medicine Division of Endocrinology, Diabetology and Nephrology University Hospital Tübingen Tübingen Germany
| | - Daniel Essigke
- Department of Internal Medicine Division of Endocrinology, Diabetology and Nephrology University Hospital Tübingen Tübingen Germany
| | - Christoph Daniel
- Institute of Nephropathology Friedrich‐Alexander University Erlangen‐Nürnberg (FAU) Erlangen Germany
| | - Kerstin Amann
- Institute of Nephropathology Friedrich‐Alexander University Erlangen‐Nürnberg (FAU) Erlangen Germany
| | - Tobias B. Huber
- III. Department of Medicine University Medical Center Hamburg‐Eppendorf Hamburg Germany
| | - Edward F. Plow
- Lerner Research InstituteCleveland Clinic Cleveland OH USA
| | - Andreas L. Birkenfeld
- Department of Internal Medicine Division of Endocrinology, Diabetology and Nephrology University Hospital Tübingen Tübingen Germany
- Institute of Diabetes Research and Metabolic Diseases (IDM) of the Helmholtz Center Munich at the University Tübingen Tübingen Germany
- German Center for Diabetes Research (DZD) at the University Tübingen Tübingen Germany
| | - Ferruh Artunc
- Department of Internal Medicine Division of Endocrinology, Diabetology and Nephrology University Hospital Tübingen Tübingen Germany
- Institute of Diabetes Research and Metabolic Diseases (IDM) of the Helmholtz Center Munich at the University Tübingen Tübingen Germany
- German Center for Diabetes Research (DZD) at the University Tübingen Tübingen Germany
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28
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Gujarati NA, Vasquez JM, Bogenhagen DF, Mallipattu SK. The complicated role of mitochondria in the podocyte. Am J Physiol Renal Physiol 2020; 319:F955-F965. [PMID: 33073585 PMCID: PMC7792691 DOI: 10.1152/ajprenal.00393.2020] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2020] [Revised: 10/13/2020] [Accepted: 10/13/2020] [Indexed: 02/06/2023] Open
Abstract
Mitochondria play a complex role in maintaining cellular function including ATP generation, generation of biosynthetic precursors for macromolecules, maintenance of redox homeostasis, and metabolic waste management. Although the contribution of mitochondrial function in various kidney diseases has been studied, there are still avenues that need to be explored under healthy and diseased conditions. Mitochondrial damage and dysfunction have been implicated in experimental models of podocytopathy as well as in humans with glomerular diseases resulting from podocyte dysfunction. Specifically, in the podocyte, metabolism is largely driven by oxidative phosphorylation or glycolysis depending on the metabolic needs. These metabolic needs may change drastically in the presence of podocyte injury in glomerular diseases such as diabetic kidney disease or focal segmental glomerulosclerosis. Here, we review the role of mitochondria in the podocyte and the factors regulating its function at baseline and in a variety of podocytopathies to identify potential targets for therapy.
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Affiliation(s)
- Nehaben A Gujarati
- Division of Nephrology, Department of Medicine, Renaissance School of Medicine at Stony Brook University, Stony Brook, New York
| | - Jessica M Vasquez
- Division of Nephrology, Department of Medicine, Renaissance School of Medicine at Stony Brook University, Stony Brook, New York
| | - Daniel F Bogenhagen
- Department of Pharmacological Sciences, Renaissance School of Medicine at Stony Brook University, Stony Brook, New York
| | - Sandeep K Mallipattu
- Division of Nephrology, Department of Medicine, Renaissance School of Medicine at Stony Brook University, Stony Brook, New York
- Renal Section, Northport Department of Veterans Affairs Medical Center, Northport, New York
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29
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Wang Y, Eng DG, Kaverina NV, Loretz CJ, Koirala A, Akilesh S, Pippin JW, Shankland SJ. Global transcriptomic changes occur in aged mouse podocytes. Kidney Int 2020; 98:1160-1173. [PMID: 32592814 PMCID: PMC7606654 DOI: 10.1016/j.kint.2020.05.052] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2020] [Revised: 05/17/2020] [Accepted: 05/28/2020] [Indexed: 01/15/2023]
Abstract
Glomerular podocytes undergo structural and functional changes with advanced age, that increase susceptibility of aging kidneys to worse outcomes following superimposed glomerular diseases. To delineate transcriptional changes in podocytes in aged mice, RNA-seq was performed on isolated populations of reporter-labeled (tdTomato) podocytes from multiple young (two to three months) and advanced aged mice (22 to 24 months, equivalent to 70 plus year old humans). Of the 2,494 differentially expressed genes, 1,219 were higher and 1,275 were lower in aged podocytes. Pathway enrichment showed that major biological processes increased in aged podocytes included immune responses, non-coding RNA metabolism, gene silencing and MAP kinase signaling. Conversely, aged podocytes showed downregulation of developmental, morphogenesis and metabolic processes. Canonical podocyte marker gene expression decreased in aged podocytes, with increases in apoptotic and senescence genes providing a mechanism for the progressive loss of podocytes seen with aging. In addition, we revealed aberrations in the podocyte autocrine signaling network, identified the top transcription factors perturbed in aged podocytes, and uncovered candidate gene modulations that might promote healthy aging in podocytes. The transcriptional signature of aging is distinct from other kidney diseases. Thus, our study provides insights into biomarker discovery and molecular targeting of the aging process itself within podocytes.
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Affiliation(s)
- Yuliang Wang
- Paul G. Allen School of Computer Science and Engineering, University of Washington, Seattle, Washington, USA; Institute for Stem Cell & Regenerative Medicine, University of Washington, Seattle, Washington, USA
| | - Diana G Eng
- Division of Nephrology, University of Washington, Seattle, Washington, USA
| | - Natalya V Kaverina
- Division of Nephrology, University of Washington, Seattle, Washington, USA
| | - Carol J Loretz
- Division of Nephrology, University of Washington, Seattle, Washington, USA
| | - Abbal Koirala
- Division of Nephrology, University of Washington, Seattle, Washington, USA
| | - Shreeram Akilesh
- Department of Pathology, University of Washington, Seattle, Washington, USA
| | - Jeffrey W Pippin
- Division of Nephrology, University of Washington, Seattle, Washington, USA
| | - Stuart J Shankland
- Division of Nephrology, University of Washington, Seattle, Washington, USA.
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30
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Rinschen MM, Saez-Rodriguez J. The tissue proteome in the multi-omic landscape of kidney disease. Nat Rev Nephrol 2020; 17:205-219. [PMID: 33028957 DOI: 10.1038/s41581-020-00348-5] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/14/2020] [Indexed: 02/07/2023]
Abstract
Kidney research is entering an era of 'big data' and molecular omics data can provide comprehensive insights into the molecular footprints of cells. In contrast to transcriptomics, proteomics and metabolomics generate data that relate more directly to the pathological symptoms and clinical parameters observed in patients. Owing to its complexity, the proteome still holds many secrets, but has great potential for the identification of drug targets. Proteomics can provide information about protein synthesis, modification and degradation, as well as insight into the physical interactions between proteins, and between proteins and other biomolecules. Thus far, proteomics in nephrology has largely focused on the discovery and validation of biomarkers, but the systematic analysis of the nephroproteome can offer substantial additional insights, including the discovery of mechanisms that trigger and propagate kidney disease. Moreover, proteome acquisition might provide a diagnostic tool that complements the assessment of a kidney biopsy sample by a pathologist. Such applications are becoming increasingly feasible with the development of high-throughput and high-coverage technologies, such as versatile mass spectrometry-based techniques and protein arrays, and encourage further proteomics research in nephrology.
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Affiliation(s)
- Markus M Rinschen
- Department of Biomedicine, Aarhus University, Aarhus, Denmark. .,III. Department of Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany. .,Department II of Internal Medicine and Center for Molecular Medicine Cologne, University of Cologne, Cologne, Germany. .,Department of Chemistry, Scripps Center for Metabolomics and Mass Spectrometry, Scripps Research, La Jolla, CA, USA.
| | - Julio Saez-Rodriguez
- Institute for Computational Biomedicine, Faculty of Medicine, Heidelberg University, and Heidelberg University Hospital, Bioquant, Heidelberg, Germany.,Joint Research Center for Computational Biomedicine, RWTH Aachen University Hospital, Aachen, Germany.,Molecular Medicine Partnership Unit, European Molecular Biology Laboratory and Heidelberg University, Heidelberg, Germany
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31
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Struk T, Nair V, Eichinger F, Kretzler M, Wedlich-Söldner R, Bayraktar S, Pavenstädt H. Transcriptome analysis of primary podocytes reveals novel calcium regulated regulatory networks. FASEB J 2020; 34:14490-14506. [PMID: 32931033 DOI: 10.1096/fj.201902493rr] [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: 10/05/2019] [Revised: 08/11/2020] [Accepted: 08/14/2020] [Indexed: 11/11/2022]
Abstract
Podocytes are pivotal in establishing the selective permeability of the glomerular filtration barrier. Recently, we showed that an increase of the intracellular calcium ion concentration [Ca2+ ] causes a rapid and transient actin reset (CaAR) measurable through live imaging microscopy using lifeact-mCherry as an actin dye in different cell types including the podocyte. This and other studies show the critical role [Ca2+ ] and the actin cytoskeleton play in podocyte homeostasis. To further investigate the role of [Ca2+ ] and the actin cytoskeleton in podocytes, we used a double fluorescent reporter mouse model to establish a primary podocyte culture system. We treated these podocytes temporarily with a Calcium Ionophore and facultatively with Latrunculin A, an inhibitor of actin polymerization. Unbiased genome wide transcriptional analysis identified a transcriptional response in podocytes to elevated [Ca2+ ] levels, affecting mRNA levels of PDGF-BB, RICTOR, and MIR17HG as mediators of Ca2+ -signaling. Comparison of the ex vivo transcriptional response from the primary podocyte culture with glomerular transcripts across a wide spectrum of CKD disease confirmed co-regulation of transcript sets, establishing the disease relevance of the model system. Our findings demonstrate novel [Ca2+ ] regulated gene networks in podocytes deepening our understanding of podocyte biology and disease.
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Affiliation(s)
- Thaddäus Struk
- Department of Medicine, University of Münster, Münster, Germany
| | - Viji Nair
- Michigan Kidney Translational Medical Core, University of Michigan, Ann Arbor, MI, USA
| | - Felix Eichinger
- Michigan Kidney Translational Medical Core, University of Michigan, Ann Arbor, MI, USA
| | - Matthias Kretzler
- Michigan Kidney Translational Medical Core, University of Michigan, Ann Arbor, MI, USA.,Internal Medicine, Department of Nephrology, University of Michigan, Ann Arbor, MI, USA
| | | | - Samet Bayraktar
- Department of Medicine, University of Münster, Münster, Germany
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32
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Ge X, Zhang T, Yu X, Muwonge AN, Anandakrishnan N, Wong NJ, Haydak JC, Reid JM, Fu J, Wong JS, Bhattacharya S, Cuttitta CM, Zhong F, Gordon RE, Salem F, Janssen W, Hone JC, Zhang A, Li H, He JC, Gusella GL, Campbell KN, Azeloglu EU. LIM-Nebulette Reinforces Podocyte Structural Integrity by Linking Actin and Vimentin Filaments. J Am Soc Nephrol 2020; 31:2372-2391. [PMID: 32737144 DOI: 10.1681/asn.2019121261] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2019] [Accepted: 06/06/2020] [Indexed: 12/14/2022] Open
Abstract
BACKGROUND Maintenance of the intricate interdigitating morphology of podocytes is crucial for glomerular filtration. One of the key aspects of specialized podocyte morphology is the segregation and organization of distinct cytoskeletal filaments into different subcellular components, for which the exact mechanisms remain poorly understood. METHODS Cells from rats, mice, and humans were used to describe the cytoskeletal configuration underlying podocyte structure. Screening the time-dependent proteomic changes in the rat puromycin aminonucleoside-induced nephropathy model correlated the actin-binding protein LIM-nebulette strongly with glomerular function. Single-cell RNA sequencing and immunogold labeling were used to determine Nebl expression specificity in podocytes. Automated high-content imaging, super-resolution microscopy, atomic force microscopy (AFM), live-cell imaging of calcium, and measurement of motility and adhesion dynamics characterized the physiologic role of LIM-nebulette in podocytes. RESULTS Nebl knockout mice have increased susceptibility to adriamycin-induced nephropathy and display morphologic, cytoskeletal, and focal adhesion abnormalities with altered calcium dynamics, motility, and Rho GTPase activity. LIM-nebulette expression is decreased in diabetic nephropathy and FSGS patients at both the transcript and protein level. In mice, rats, and humans, LIM-nebulette expression is localized to primary, secondary, and tertiary processes of podocytes, where it colocalizes with focal adhesions as well as with vimentin fibers. LIM-nebulette shRNA knockdown in immortalized human podocytes leads to dysregulation of vimentin filament organization and reduced cellular elasticity as measured by AFM indentation. CONCLUSIONS LIM-nebulette is a multifunctional cytoskeletal protein that is critical in the maintenance of podocyte structural integrity through active reorganization of focal adhesions, the actin cytoskeleton, and intermediate filaments.
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Affiliation(s)
- Xuhua Ge
- Division of Nephrology, Department of Medicine, Icahn School of Medicine at Mount Sinai, New York, New York
| | - Tao Zhang
- Division of Nephrology, Department of Medicine, Icahn School of Medicine at Mount Sinai, New York, New York
| | - Xiaoxia Yu
- Division of Nephrology, Department of Medicine, Icahn School of Medicine at Mount Sinai, New York, New York
| | - Alecia N Muwonge
- Division of Nephrology, Department of Medicine, Icahn School of Medicine at Mount Sinai, New York, New York
| | - Nanditha Anandakrishnan
- Division of Nephrology, Department of Medicine, Icahn School of Medicine at Mount Sinai, New York, New York
| | - Nicholas J Wong
- Division of Nephrology, Department of Medicine, Icahn School of Medicine at Mount Sinai, New York, New York
| | - Jonathan C Haydak
- Division of Nephrology, Department of Medicine, Icahn School of Medicine at Mount Sinai, New York, New York
| | - Jordan M Reid
- Division of Nephrology, Department of Medicine, Icahn School of Medicine at Mount Sinai, New York, New York
| | - Jia Fu
- Division of Nephrology, Department of Medicine, Icahn School of Medicine at Mount Sinai, New York, New York
| | - Jenny S Wong
- Division of Nephrology, Department of Medicine, Icahn School of Medicine at Mount Sinai, New York, New York
| | - Smiti Bhattacharya
- Division of Nephrology, Department of Medicine, Icahn School of Medicine at Mount Sinai, New York, New York.,Department of Mechanical Engineering, Columbia University, New York, New York
| | - Christina M Cuttitta
- Division of Nephrology, Department of Medicine, Icahn School of Medicine at Mount Sinai, New York, New York
| | - Fang Zhong
- Division of Nephrology, Department of Medicine, Icahn School of Medicine at Mount Sinai, New York, New York
| | - Ronald E Gordon
- Department of Pathology, Icahn School of Medicine at Mount Sinai, New York, New York
| | - Fadi Salem
- Department of Pathology, Icahn School of Medicine at Mount Sinai, New York, New York
| | - William Janssen
- Department of Neuroscience, Icahn School of Medicine at Mount Sinai, New York, New York
| | - James C Hone
- Department of Mechanical Engineering, Columbia University, New York, New York
| | - Aihua Zhang
- Department of Nephrology, Children's Hospital of Nanjing Medical University, Nanjing, China
| | - Hong Li
- Department of Microbiology, Biochemistry and Molecular Genetics, Rutgers University-New Jersey Medical School, Newark, New Jersey
| | - John C He
- Division of Nephrology, Department of Medicine, Icahn School of Medicine at Mount Sinai, New York, New York.,Department of Pharmacological Sciences, Icahn School of Medicine at Mount Sinai, New York, New York
| | - G Luca Gusella
- Division of Nephrology, Department of Medicine, Icahn School of Medicine at Mount Sinai, New York, New York
| | - Kirk N Campbell
- Division of Nephrology, Department of Medicine, Icahn School of Medicine at Mount Sinai, New York, New York
| | - Evren U Azeloglu
- Division of Nephrology, Department of Medicine, Icahn School of Medicine at Mount Sinai, New York, New York .,Department of Pharmacological Sciences, Icahn School of Medicine at Mount Sinai, New York, New York
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33
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Saoud R, Jaffa MA, Habib A, Zhao J, Al Hariri M, Zhu R, Hasan A, Ziyadeh FN, Kobeissy F, Mechref Y, Jaffa AA. Modulation of proteomic and inflammatory signals by Bradykinin in podocytes. J Adv Res 2020; 24:409-422. [PMID: 32518694 PMCID: PMC7270529 DOI: 10.1016/j.jare.2020.05.021] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2020] [Revised: 05/16/2020] [Accepted: 05/18/2020] [Indexed: 01/19/2023] Open
Abstract
Podocyte damage is one of the hallmarks of diabetic nephropathy leading to proteinuria and kidney damage. The underlying mechanisms of podocyte injury are not well defined. Bradykinin (BK) was shown to contribute to diabetic kidney disease. Here, we evaluated the temporal changes in proteome profile and inflammatory signals of podocytes in response to BK (10−7M). Protein profile was evaluated by liquid chromatography mass Spectrometry (LC-MS/MS) analysis. Proteome profile analysis of podocytes treated with BK (10−7M) for 3 and 6 h, revealed 61 proteins that were differentially altered compared to unstimulated control podocytes. Pathway enrichment analysis suggested inhibition of cell death pathways, engagement of cytoskeletal elements and activation of inflammatory pathways. One of the inflammatory proteins that was identified to be induced by BK treatment is Prostaglandin (PG) H Synthase-2 (Cyclooxygenase-2, COX-2). In addition, BK significantly induced the production and release of PGE2 and this effect was inhibited by both COX-2 and MEK Kinase inhibitors, demonstrating that the production of PGE2 by BK is mediated via COX-2 and MAPK-dependent mechanisms. These findings provide a global understanding of the effector modulated proteome in response to BK and also reveal BK as an important modulator of inflammation and a potential player in podocyte injury.
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Affiliation(s)
- Richard Saoud
- Department of Biochemistry and Molecular Genetics, Faculty of Medicine, American University of Beirut, Lebanon
| | - Miran A Jaffa
- Epidemiology and Population Health Department, Faculty of Health Sciences, American University of Beirut, Lebanon
| | - Aida Habib
- Department of Biochemistry and Molecular Genetics, Faculty of Medicine, American University of Beirut, Lebanon.,INSERM-U1149, Centre de Recherche sur l'Inflammation, Sorbonne Paris Cité, Laboratoire d'Excellence Inflamex, Faculté de Médecine, Site Xavier Bichat, Université de Paris, France
| | - Jingfu Zhao
- Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, TX 79409, United States
| | - Moustafa Al Hariri
- Department of Biochemistry and Molecular Genetics, Faculty of Medicine, American University of Beirut, Lebanon
| | - Rui Zhu
- Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, TX 79409, United States
| | - Anwarul Hasan
- Department of Mechanical and Industrial Engineering, Qatar University, Qatar
| | - Fuad N Ziyadeh
- Department of Biochemistry and Molecular Genetics, Faculty of Medicine, American University of Beirut, Lebanon.,Department of Internal Medicine, Faculty of Medicine, American University of Beirut, Lebanon
| | - Firas Kobeissy
- Department of Biochemistry and Molecular Genetics, Faculty of Medicine, American University of Beirut, Lebanon
| | - Yehia Mechref
- Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, TX 79409, United States
| | - Ayad A Jaffa
- Department of Biochemistry and Molecular Genetics, Faculty of Medicine, American University of Beirut, Lebanon
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34
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Concerted EP2 and EP4 Receptor Signaling Stimulates Autocrine Prostaglandin E 2 Activation in Human Podocytes. Cells 2020; 9:cells9051256. [PMID: 32438662 PMCID: PMC7290667 DOI: 10.3390/cells9051256] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2020] [Revised: 04/29/2020] [Accepted: 05/14/2020] [Indexed: 12/14/2022] Open
Abstract
Glomerular hyperfiltration is an important mechanism in the development of albuminuria. During hyperfiltration, podocytes are exposed to increased fluid flow shear stress (FFSS) in Bowman’s space. Elevated Prostaglandin E2 (PGE2) synthesis and upregulated cyclooxygenase 2 (Cox2) are associated with podocyte injury by FFSS. We aimed to elucidate a PGE2 autocrine/paracrine pathway in human podocytes (hPC). We developed a modified liquid chromatography tandem mass spectrometry (LC/ESI-MS/MS) protocol to quantify cellular PGE2, 15-keto-PGE2, and 13,14-dihydro-15-keto-PGE2 levels. hPC were treated with PGE2 with or without separate or combined blockade of prostaglandin E receptors (EP), EP2, and EP4. Furthermore, the effect of FFSS on COX2, PTGER2, and PTGER4 expression in hPC was quantified. In hPC, stimulation with PGE2 led to an EP2- and EP4-dependent increase in cyclic adenosine monophosphate (cAMP) and COX2, and induced cellular PGE2. PTGER4 was downregulated after PGE2 stimulation in hPC. In the corresponding LC/ESI-MS/MS in vivo analysis at the tissue level, increased PGE2 and 15-keto-PGE2 levels were observed in isolated glomeruli obtained from a well-established rat model with glomerular hyperfiltration, the Munich Wistar Frömter rat. COX2 and PTGER2 were upregulated by FFSS. Our data thus support an autocrine/paracrine COX2/PGE2 pathway in hPC linked to concerted EP2 and EP4 signaling.
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35
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Bukosza EN, Kratochwill K, Kornauth C, Schachner H, Aufricht C, Gebeshuber CA. Podocyte RNA sequencing reveals Wnt- and ECM-associated genes as central in FSGS. PLoS One 2020; 15:e0231898. [PMID: 32302353 PMCID: PMC7164636 DOI: 10.1371/journal.pone.0231898] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2019] [Accepted: 04/02/2020] [Indexed: 12/18/2022] Open
Abstract
Loss of podocyte differentiation can cause nephrotic-range proteinuria and Focal and Segmental Glomerulosclerosis (FSGS). As specific therapy is still lacking, FSGS frequently progresses to end-stage renal disease. The exact molecular mechanisms of FSGS and gene expression changes in podocytes are complex and widely unknown as marker changes have mostly been assessed on the glomerular level. To gain a better insight, we isolated podocytes of miR-193a overexpressing mice, which suffer from FSGS due to suppression of the podocyte master regulator Wt1. We characterised the podocytic gene expression changes by RNAseq and identified many novel candidate genes not linked to FSGS so far. This included strong upregulation of the receptor tyrosine kinase EphA6 and a massive dysregulation of circadian genes including the loss of the transcriptional activator Arntl. By comparison with podocyte-specific changes in other FSGS models we found a shared dysregulation of genes associated with the Wnt signaling cascade, while classical podocyte-specific genes appeared widely unaltered. An overlap with gene expression screens from human FSGS patients revealed a strong enrichment in genes associated with extra-cellular matrix (ECM) and metabolism. Our data suggest that FSGS progression might frequently depend on pathways that are often overlooked when considering podocyte homeostasis.
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Affiliation(s)
- Eva Nora Bukosza
- Translational Medicine Institute, Semmelweis University Budapest, Budapest, Hungary
- Division of Pediatric Nephrology and Gastroenterology, Department of Pediatrics and Adolescent Medicine, Medical University of Vienna, Vienna, Austria
| | - Klaus Kratochwill
- Division of Pediatric Nephrology and Gastroenterology, Department of Pediatrics and Adolescent Medicine, Medical University of Vienna, Vienna, Austria
- Christian Doppler Laboratory for Molecular Stress Research in Peritoneal Dialysis, Department of Pediatrics and Adolescent Medicine, Medical University of Vienna, Vienna, Austria
| | - Christoph Kornauth
- Clinical Division of Hematology and Hemostaseology, Department of Internal Medicine I, Medical University of Vienna, Vienna, Austria
- Clinical Institute of Pathology, Medical University of Vienna, Vienna, Austria
| | - Helga Schachner
- Clinical Institute of Pathology, Medical University of Vienna, Vienna, Austria
| | - Christoph Aufricht
- Division of Pediatric Nephrology and Gastroenterology, Department of Pediatrics and Adolescent Medicine, Medical University of Vienna, Vienna, Austria
| | - Christoph A. Gebeshuber
- Division of Pediatric Nephrology and Gastroenterology, Department of Pediatrics and Adolescent Medicine, Medical University of Vienna, Vienna, Austria
- Clinical Institute of Pathology, Medical University of Vienna, Vienna, Austria
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36
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Koehler S, Kuczkowski A, Kuehne L, Jüngst C, Hoehne M, Grahammer F, Eddy S, Kretzler M, Beck BB, Höhfeld J, Schermer B, Benzing T, Brinkkoetter PT, Rinschen MM. Proteome Analysis of Isolated Podocytes Reveals Stress Responses in Glomerular Sclerosis. J Am Soc Nephrol 2020; 31:544-559. [PMID: 32047005 DOI: 10.1681/asn.2019030312] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2019] [Accepted: 12/04/2019] [Indexed: 12/15/2022] Open
Abstract
BACKGROUND Understanding podocyte-specific responses to injury at a systems level is difficult because injury leads to podocyte loss or an increase of extracellular matrix, altering glomerular cellular composition. Finding a window into early podocyte injury might help identify molecular pathways involved in the podocyte stress response. METHODS We developed an approach to apply proteome analysis to very small samples of purified podocyte fractions. To examine podocytes in early disease states in FSGS mouse models, we used podocyte fractions isolated from individual mice after chemical induction of glomerular disease (with Doxorubicin or LPS). We also applied single-glomerular proteome analysis to tissue from patients with FSGS. RESULTS Transcriptome and proteome analysis of glomeruli from patients with FSGS revealed an underrepresentation of podocyte-specific genes and proteins in late-stage disease. Proteome analysis of purified podocyte fractions from FSGS mouse models showed an early stress response that includes perturbations of metabolic, mechanical, and proteostasis proteins. Additional analysis revealed a high correlation between the amount of proteinuria and expression levels of the mechanosensor protein Filamin-B. Increased expression of Filamin-B in podocytes in biopsy samples from patients with FSGS, in single glomeruli from proteinuric rats, and in podocytes undergoing mechanical stress suggests that this protein has a role in detrimental stress responses. In Drosophila, nephrocytes with reduced filamin homolog Cher displayed altered filtration capacity, but exhibited no change in slit diaphragm structure. CONCLUSIONS We identified conserved mechanisms of the podocyte stress response through ultrasensitive proteome analysis of human glomerular FSGS tissue and purified native mouse podocytes during early disease stages. This approach enables systematic comparisons of large-scale proteomics data and phenotype-to-protein correlation.
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Affiliation(s)
- Sybille Koehler
- Department II of Internal Medicine and Center for Molecular Medicine Cologne, University of Cologne, Faculty of Medicine and University Hospital Cologne, Cologne, Germany.,Biomedical Sciences, University of Edinburgh, Edinburgh, Scotland, United Kingdom
| | - Alexander Kuczkowski
- Department II of Internal Medicine and Center for Molecular Medicine Cologne, University of Cologne, Faculty of Medicine and University Hospital Cologne, Cologne, Germany
| | - Lucas Kuehne
- Department II of Internal Medicine and Center for Molecular Medicine Cologne, University of Cologne, Faculty of Medicine and University Hospital Cologne, Cologne, Germany
| | - Christian Jüngst
- Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases, University of Cologne, Cologne, Germany
| | - Martin Hoehne
- Department II of Internal Medicine and Center for Molecular Medicine Cologne, University of Cologne, Faculty of Medicine and University Hospital Cologne, Cologne, Germany.,Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases, University of Cologne, Cologne, Germany
| | - Florian Grahammer
- III. Department of Medicine, University Medical Center Hamburg-Eppendorf, Eppendorf, Hamburg, Germany
| | - Sean Eddy
- Division of Nephrology, Department of Internal Medicine, and
| | - Matthias Kretzler
- Division of Nephrology, Department of Internal Medicine, and.,Department of Computational Medicine and Bioinformatics, University of Michigan, Ann Arbor, Michigan
| | - Bodo B Beck
- Department of Human Genetics, University Hospital Cologne, Cologne, Germany
| | - Jörg Höhfeld
- Cell Biology, University of Bonn, Bonn, Germany; and
| | - Bernhard Schermer
- Department II of Internal Medicine and Center for Molecular Medicine Cologne, University of Cologne, Faculty of Medicine and University Hospital Cologne, Cologne, Germany.,Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases, University of Cologne, Cologne, Germany
| | - Thomas Benzing
- Department II of Internal Medicine and Center for Molecular Medicine Cologne, University of Cologne, Faculty of Medicine and University Hospital Cologne, Cologne, Germany.,Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases, University of Cologne, Cologne, Germany
| | - Paul T Brinkkoetter
- Department II of Internal Medicine and Center for Molecular Medicine Cologne, University of Cologne, Faculty of Medicine and University Hospital Cologne, Cologne, Germany;
| | - Markus M Rinschen
- Department II of Internal Medicine and Center for Molecular Medicine Cologne, University of Cologne, Faculty of Medicine and University Hospital Cologne, Cologne, Germany; .,Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases, University of Cologne, Cologne, Germany.,Center for Metabolomics and Mass Spectrometry, The Scripps Research Institute, La Jolla, California
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Stotter BR, Talbot BE, Capen DE, Artelt N, Zeng J, Matsumoto Y, Endlich N, Cummings RD, Schlondorff JS. Cosmc-dependent mucin-type O-linked glycosylation is essential for podocyte function. Am J Physiol Renal Physiol 2020; 318:F518-F530. [PMID: 31904283 DOI: 10.1152/ajprenal.00399.2019] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Mucin-type O-linked glycosylation, a posttranslational modification affecting the stability and biophysical characteristics of proteins, requires C1GalT1 (T synthase) and its obligate, X-linked chaperone Cosmc. Hypomorphic C1GalT1 mutations cause renal failure via not yet established mechanisms. We hypothesize that impaired Cosmc-dependent O-glycosylation in podocytes is sufficient to cause disease. Podocyte-specific Cosmc knockout mice were generated and phenotyped to test this hypothesis. Female heterozygous mice displaying mosaic inactivation of Cosmc in podocytes due to random X-linked inactivation were also examined. Mice with podocyte-specific Cosmc deletion develop profound albuminuria, foot process effacement, glomerular sclerosis, progressive renal failure, and impaired survival. Glomerular transcriptome analysis reveals early changes in cell adhesion, extracellular matrix organization, and chemokine-mediated signaling pathways, coupled with podocyte loss. Expression of the O-glycoprotein podoplanin was lost, while Tn antigen, representing immature O-glycans, was most abundantly found on podocalyxin. In contrast to hemizygous male and homozygous female animals, heterozygous female mosaic animals developed only mild albuminuria, focal foot process effacement, and nonprogressive kidney disease. Ultrastructurally, Cosmc-deficient podocytes formed Tn antigen-positive foot processes interdigitating with those of normal podocytes but not with other Cosmc-deficient cells. This suggests a cell nonautonomous mechanism for mucin-type O-glycoproteins in maintaining podocyte function. In summary, our findings demonstrated an essential and likely cell nonautonomous role for mucin-type O-glycosylation for podocyte function.
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Affiliation(s)
- Brian R Stotter
- Division of Nephrology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts.,Division of Nephrology, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts
| | - Brianna E Talbot
- Division of Nephrology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts
| | - Diane E Capen
- Center for Systems Biology/Program in Membrane Biology, Massachusetts General Hospital, Boston, Massachusetts
| | - Nadine Artelt
- Institute for Anatomy and Cell Biology, University Medicine Greifswald, Greifswald, Germany
| | - Junwei Zeng
- National Center for Functional Glycomics, Department of Surgery, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts
| | - Yasuyuki Matsumoto
- National Center for Functional Glycomics, Department of Surgery, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts
| | - Nicole Endlich
- Institute for Anatomy and Cell Biology, University Medicine Greifswald, Greifswald, Germany
| | - Richard D Cummings
- National Center for Functional Glycomics, Department of Surgery, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts
| | - Johannes S Schlondorff
- Division of Nephrology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts
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38
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Bork T, Liang W, Yamahara K, Lee P, Tian Z, Liu S, Schell C, Thedieck K, Hartleben B, Patel K, Tharaux PL, Lenoir O, Huber TB. Podocytes maintain high basal levels of autophagy independent of mtor signaling. Autophagy 2019; 16:1932-1948. [PMID: 31865844 PMCID: PMC7595647 DOI: 10.1080/15548627.2019.1705007] [Citation(s) in RCA: 66] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
While constant basal levels of macroautophagy/autophagy are a prerequisite to preserve long-lived podocytes at the filtration barrier, MTOR regulates at the same time podocyte size and compensatory hypertrophy. Since MTOR is known to generally suppress autophagy, the apparently independent regulation of these two key pathways of glomerular maintenance remained puzzling. We now report that long-term genetic manipulation of MTOR activity does in fact not influence high basal levels of autophagy in podocytes either in vitro or in vivo. Instead we present data showing that autophagy in podocytes is mainly controlled by AMP-activated protein kinase (AMPK) and ULK1 (unc-51 like kinase 1). Pharmacological inhibition of MTOR further shows that the uncoupling of MTOR activity and autophagy is time dependent. Together, our data reveal a novel and unexpected cell-specific mechanism, which permits concurrent MTOR activity as well as high basal autophagy rates in podocytes. Thus, these data indicate manipulation of the AMPK-ULK1 axis rather than inhibition of MTOR as a promising therapeutic intervention to enhance autophagy and preserve podocyte homeostasis in glomerular diseases. Abbreviations: AICAR: 5-aminoimidazole-4-carboxamide ribonucleotide; AMPK: AMP-activated protein kinase; ATG: autophagy related; BW: body weight; Cq: chloroquine; ER: endoplasmic reticulum; ESRD: end stage renal disease; FACS: fluorescence activated cell sorting; GFP: green fluorescent protein; i.p.: intra peritoneal; MAP1LC3/LC3: microtubule-associated protein 1 light chain 3; MTOR: mechanistic target of rapamycin kinase; NPHS1: nephrosis 1, nephrin; NPHS2: nephrosis 2, podocin; PLA: proximity-ligation assay; PRKAA: 5ʹ-AMP-activated protein kinase catalytic subunit alpha; RPTOR/RAPTOR: regulatory associated protein of MTOR, complex 1; RFP: red fluorescent protein; TSC1: tuberous sclerosis 1; ULK1: unc-51 like kinase 1
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Affiliation(s)
- Tillmann Bork
- Department of Medicine IV, Faculty of Medicine, University of Freiburg , Freiburg, Germany
| | - Wei Liang
- Department of Medicine IV, Faculty of Medicine, University of Freiburg , Freiburg, Germany.,Division of Nephrology, Renmin Hospital of Wuhan University , Wuhan, China
| | - Kosuke Yamahara
- Department of Medicine IV, Faculty of Medicine, University of Freiburg , Freiburg, Germany.,Department of Medicine, Shiga University of Medical Science , Otsu, Japan
| | - Philipp Lee
- Department of Medicine IV, Faculty of Medicine, University of Freiburg , Freiburg, Germany
| | - Zhejia Tian
- Department of Medicine IV, Faculty of Medicine, University of Freiburg , Freiburg, Germany
| | - Shuya Liu
- III. Department of Medicine, University Medical Center Hamburg-Eppendorf , Hamburg, Germany
| | - Christoph Schell
- Department of Medicine IV, Faculty of Medicine, University of Freiburg , Freiburg, Germany.,Institute of Surgical Pathology, Faculty of Medicine, University of Freiburg , Freiburg, Germany.,Berta-Ottenstein Programme, Faculty of Medicine, University of Freiburg , Freiburg, Germany
| | - Kathrin Thedieck
- Institute of Biochemistry and Center for Molecular Biosciences Innsbruck, University of Innsbruck , Innsbruck, Austria.,Department of Pediatrics, Section Systems Medicine of Metabolism and Signaling, University of Groningen, University Medical Center Groningen (UMCG) , Groningen, The Netherlands.,Department of Neuroscience, School of Medicine and Health Sciences, Carl von Ossietzky University Oldenburg , Oldenburg, Germany
| | - Bjoern Hartleben
- Institute of Pathology, Hannover Medical School , Hannover, Germany
| | - Ketan Patel
- School of Biological Science, University of Reading , Reading, UK.,FFRIAS, Freiburg Institute for Advanced Studies, Albert-Ludwigs-University , Freiburg, Germany
| | - Pierre-Louis Tharaux
- PARCC, INSERM, Université de Paris , Paris, France.,Nephrology Division, Georges Pompidou European Hospital , Paris, France
| | | | - Tobias B Huber
- III. Department of Medicine, University Medical Center Hamburg-Eppendorf , Hamburg, Germany
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39
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Rinschen MM, Gödel M, Grahammer F, Zschiedrich S, Helmstädter M, Kretz O, Zarei M, Braun DA, Dittrich S, Pahmeyer C, Schroder P, Teetzen C, Gee H, Daouk G, Pohl M, Kuhn E, Schermer B, Küttner V, Boerries M, Busch H, Schiffer M, Bergmann C, Krüger M, Hildebrandt F, Dengjel J, Benzing T, Huber TB. A Multi-layered Quantitative In Vivo Expression Atlas of the Podocyte Unravels Kidney Disease Candidate Genes. Cell Rep 2019; 23:2495-2508. [PMID: 29791858 PMCID: PMC5986710 DOI: 10.1016/j.celrep.2018.04.059] [Citation(s) in RCA: 60] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2017] [Revised: 02/07/2018] [Accepted: 04/15/2018] [Indexed: 12/31/2022] Open
Abstract
Damage to and loss of glomerular podocytes has been identified as the culprit lesion in progressive kidney diseases. Here, we combine mass spectrometry-based proteomics with mRNA sequencing, bioinformatics, and hypothesis-driven studies to provide a comprehensive and quantitative map of mammalian podocytes that identifies unanticipated signaling pathways. Comparison of the in vivo datasets with proteomics data from podocyte cell cultures showed a limited value of available cell culture models. Moreover, in vivo stable isotope labeling by amino acids uncovered surprisingly rapid synthesis of mitochondrial proteins under steady-state conditions that was perturbed under autophagy-deficient, disease-susceptible conditions. Integration of acquired omics dimensions suggested FARP1 as a candidate essential for podocyte function, which could be substantiated by genetic analysis in humans and knockdown experiments in zebrafish. This work exemplifies how the integration of multi-omics datasets can identify a framework of cell-type-specific features relevant for organ health and disease. Deep proteome and transcriptome analyses of native podocytes unravel druggable targets Static and dynamic proteomics uncover features of podocyte identity and proteostasis Candidate genes for nephrotic syndrome were predicted based on multi-omic integration FARP1 is a previously unreported candidate gene for human proteinuric kidney disease
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Affiliation(s)
- Markus M Rinschen
- Department II of Internal Medicine, University of Cologne, 50931 Cologne, Germany; Center for Molecular Medicine Cologne (CMMC), University of Cologne, 50931 Cologne, Germany; Cologne Excellence Cluster on Cellular Stress Responses in Aging Associated Diseases (CECAD), University of Cologne, 50931 Cologne, Germany; Systems Biology of Ageing Cologne (Sybacol), University of Cologne, 50931 Cologne, Germany.
| | - Markus Gödel
- III. Department of Medicine, University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany; Department of Medicine IV, Medical Center and Faculty of Medicine, University of Freiburg, 79110 Freiburg, Germany
| | - Florian Grahammer
- III. Department of Medicine, University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany; Department of Medicine IV, Medical Center and Faculty of Medicine, University of Freiburg, 79110 Freiburg, Germany
| | - Stefan Zschiedrich
- Department of Medicine IV, Medical Center and Faculty of Medicine, University of Freiburg, 79110 Freiburg, Germany
| | - Martin Helmstädter
- Department of Medicine IV, Medical Center and Faculty of Medicine, University of Freiburg, 79110 Freiburg, Germany
| | - Oliver Kretz
- III. Department of Medicine, University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany; Department of Medicine IV, Medical Center and Faculty of Medicine, University of Freiburg, 79110 Freiburg, Germany
| | - Mostafa Zarei
- Freiburg Institute for Advanced Studies (FRIAS), University of Freiburg, 79104 Freiburg, Germany; Center for Systems Biology (ZBSA), Albert Ludwigs University, 79104 Freiburg, Germany
| | - Daniela A Braun
- Division of Nephrology, Boston Children's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Sebastian Dittrich
- Department II of Internal Medicine, University of Cologne, 50931 Cologne, Germany; Center for Molecular Medicine Cologne (CMMC), University of Cologne, 50931 Cologne, Germany
| | - Caroline Pahmeyer
- Department II of Internal Medicine, University of Cologne, 50931 Cologne, Germany; Center for Molecular Medicine Cologne (CMMC), University of Cologne, 50931 Cologne, Germany
| | - Patricia Schroder
- Department of Medicine/Nephrology, Hannover Medical School, 30625 Hannover, Germany; Mount Desert Island Biological Laboratory, Salisbury Cove, ME 04609, USA
| | - Carolin Teetzen
- Department of Medicine IV, Medical Center and Faculty of Medicine, University of Freiburg, 79110 Freiburg, Germany
| | - HeonYung Gee
- Mount Desert Island Biological Laboratory, Salisbury Cove, ME 04609, USA; Department of Pharmacology, Brain Korea 21 PLUS Project for Medical Sciences, Yonsei University College of Medicine, Seoul 03722, Korea
| | - Ghaleb Daouk
- Division of Nephrology, Boston Children's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Martin Pohl
- Department of General Pediatrics, Adolescent Medicine and Neonatology, Medical Center and Faculty of Medicine, University of Freiburg, 79106 Freiburg, Germany
| | - Elisa Kuhn
- Center for Human Genetics, Bioscientia, 55218 Ingelheim, Germany
| | - Bernhard Schermer
- Department II of Internal Medicine, University of Cologne, 50931 Cologne, Germany; Center for Molecular Medicine Cologne (CMMC), University of Cologne, 50931 Cologne, Germany; Cologne Excellence Cluster on Cellular Stress Responses in Aging Associated Diseases (CECAD), University of Cologne, 50931 Cologne, Germany; Systems Biology of Ageing Cologne (Sybacol), University of Cologne, 50931 Cologne, Germany
| | - Victoria Küttner
- Department for Neuroanatomy, University of Freiburg, 79104 Freiburg, Germany; Freiburg Institute for Advanced Studies (FRIAS), University of Freiburg, 79104 Freiburg, Germany; Department of Dermatology, Medical Center - University of Freiburg, 79106 Freiburg, Germany
| | - Melanie Boerries
- Systems Biology of the Cellular Microenvironment Group, Institute of Molecular Medicine and Cell Research, Albert Ludwigs University Freiburg, 79106 Freiburg, Germany; German Cancer Consortium (DKTK), 79106 Freiburg, Germany; German Cancer Research Center (DKFZ), 69120 Heidelberg, Germany
| | - Hauke Busch
- Systems Biology of the Cellular Microenvironment Group, Institute of Molecular Medicine and Cell Research, Albert Ludwigs University Freiburg, 79106 Freiburg, Germany; Lübeck Institute for Experimental Dermatology (LIED), University of Lübeck, 23562 Lübeck, Germany
| | - Mario Schiffer
- Department of Medicine/Nephrology, Hannover Medical School, 30625 Hannover, Germany; Mount Desert Island Biological Laboratory, Salisbury Cove, ME 04609, USA
| | - Carsten Bergmann
- Department of Medicine IV, Medical Center and Faculty of Medicine, University of Freiburg, 79110 Freiburg, Germany; Center for Human Genetics, Bioscientia, 55218 Ingelheim, Germany
| | - Marcus Krüger
- Center for Molecular Medicine Cologne (CMMC), University of Cologne, 50931 Cologne, Germany; Cologne Excellence Cluster on Cellular Stress Responses in Aging Associated Diseases (CECAD), University of Cologne, 50931 Cologne, Germany
| | - Friedhelm Hildebrandt
- Division of Nephrology, Boston Children's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Joern Dengjel
- Freiburg Institute for Advanced Studies (FRIAS), University of Freiburg, 79104 Freiburg, Germany; Center for Systems Biology (ZBSA), Albert Ludwigs University, 79104 Freiburg, Germany; Department of Dermatology, Medical Center - University of Freiburg, 79106 Freiburg, Germany; Department of Biology, University of Fribourg, 1700 Fribourg, Switzerland; BIOSS Centre for Biological Signaling Studies, Albert Ludwigs University Freiburg, 79104 Freiburg, Germany
| | - Thomas Benzing
- Department II of Internal Medicine, University of Cologne, 50931 Cologne, Germany; Center for Molecular Medicine Cologne (CMMC), University of Cologne, 50931 Cologne, Germany; Cologne Excellence Cluster on Cellular Stress Responses in Aging Associated Diseases (CECAD), University of Cologne, 50931 Cologne, Germany; Systems Biology of Ageing Cologne (Sybacol), University of Cologne, 50931 Cologne, Germany.
| | - Tobias B Huber
- III. Department of Medicine, University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany; Department of Medicine IV, Medical Center and Faculty of Medicine, University of Freiburg, 79110 Freiburg, Germany; Freiburg Institute for Advanced Studies (FRIAS), University of Freiburg, 79104 Freiburg, Germany; Center for Systems Biology (ZBSA), Albert Ludwigs University, 79104 Freiburg, Germany; BIOSS Centre for Biological Signaling Studies, Albert Ludwigs University Freiburg, 79104 Freiburg, Germany.
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40
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Puelles VG, van der Wolde JW, Wanner N, Scheppach MW, Cullen-McEwen LA, Bork T, Lindenmeyer MT, Gernhold L, Wong MN, Braun F, Cohen CD, Kett MM, Kuppe C, Kramann R, Saritas T, van Roeyen CR, Moeller MJ, Tribolet L, Rebello R, Sun YB, Li J, Müller-Newen G, Hughson MD, Hoy WE, Person F, Wiech T, Ricardo SD, Kerr PG, Denton KM, Furic L, Huber TB, Nikolic-Paterson DJ, Bertram JF. mTOR-mediated podocyte hypertrophy regulates glomerular integrity in mice and humans. JCI Insight 2019; 4:99271. [PMID: 31534053 DOI: 10.1172/jci.insight.99271] [Citation(s) in RCA: 61] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2017] [Accepted: 08/08/2019] [Indexed: 02/06/2023] Open
Abstract
The cellular origins of glomerulosclerosis involve activation of parietal epithelial cells (PECs) and progressive podocyte depletion. While mammalian target of rapamycin-mediated (mTOR-mediated) podocyte hypertrophy is recognized as an important signaling pathway in the context of glomerular disease, the role of podocyte hypertrophy as a compensatory mechanism preventing PEC activation and glomerulosclerosis remains poorly understood. In this study, we show that glomerular mTOR and PEC activation-related genes were both upregulated and intercorrelated in biopsies from patients with focal segmental glomerulosclerosis (FSGS) and diabetic nephropathy, suggesting both compensatory and pathological roles. Advanced morphometric analyses in murine and human tissues identified podocyte hypertrophy as a compensatory mechanism aiming to regulate glomerular functional integrity in response to somatic growth, podocyte depletion, and even glomerulosclerosis - all of this in the absence of detectable podocyte regeneration. In mice, pharmacological inhibition of mTOR signaling during acute podocyte loss impaired hypertrophy of remaining podocytes, resulting in unexpected albuminuria, PEC activation, and glomerulosclerosis. Exacerbated and persistent podocyte hypertrophy enabled a vicious cycle of podocyte loss and PEC activation, suggesting a limit to its beneficial effects. In summary, our data highlight a critical protective role of mTOR-mediated podocyte hypertrophy following podocyte loss in order to preserve glomerular integrity, preventing PEC activation and glomerulosclerosis.
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Affiliation(s)
- Victor G Puelles
- Development and Stem Cells Program, Monash Biomedicine Discovery Institute and Department of Anatomy and Developmental Biology, Monash University, Melbourne, Australia.,Department of Nephrology, Monash Health, Melbourne, Australia.,Center for Inflammatory Diseases, Monash University, Melbourne, Australia.,III. Department of Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - James W van der Wolde
- Development and Stem Cells Program, Monash Biomedicine Discovery Institute and Department of Anatomy and Developmental Biology, Monash University, Melbourne, Australia
| | - Nicola Wanner
- III. Department of Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | | | - Luise A Cullen-McEwen
- Development and Stem Cells Program, Monash Biomedicine Discovery Institute and Department of Anatomy and Developmental Biology, Monash University, Melbourne, Australia
| | - Tillmann Bork
- Renal Division, University Medical Center Freiburg, Freiburg, Germany
| | - Maja T Lindenmeyer
- III. Department of Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Lukas Gernhold
- III. Department of Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Milagros N Wong
- III. Department of Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Fabian Braun
- III. Department of Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Clemens D Cohen
- Nephrological Center Medical Clinic and Polyclinic IV, University of Munich, Munich, Germany
| | - Michelle M Kett
- Cardiovascular Program, Monash Biomedicine Discovery Institute and Department of Physiology, Monash University, Melbourne, Australia
| | | | | | | | | | | | - Leon Tribolet
- Development and Stem Cells Program, Monash Biomedicine Discovery Institute and Department of Anatomy and Developmental Biology, Monash University, Melbourne, Australia
| | - Richard Rebello
- Development and Stem Cells Program, Monash Biomedicine Discovery Institute and Department of Anatomy and Developmental Biology, Monash University, Melbourne, Australia
| | - Yu By Sun
- Development and Stem Cells Program, Monash Biomedicine Discovery Institute and Department of Anatomy and Developmental Biology, Monash University, Melbourne, Australia
| | - Jinhua Li
- Development and Stem Cells Program, Monash Biomedicine Discovery Institute and Department of Anatomy and Developmental Biology, Monash University, Melbourne, Australia
| | - Gerhard Müller-Newen
- Institute of Biochemistry and Molecular Biology, RWTH Aachen University, Aachen, Germany
| | - Michael D Hughson
- Department of Pathology, University of Mississippi Medical Center, Jackson, Mississippi, USA
| | - Wendy E Hoy
- Centre for Chronic Disease, The University of Queensland, Brisbane, Queensland, Australia
| | - Fermin Person
- Institute of Pathology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Thorsten Wiech
- Institute of Pathology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Sharon D Ricardo
- Development and Stem Cells Program, Monash Biomedicine Discovery Institute and Department of Anatomy and Developmental Biology, Monash University, Melbourne, Australia
| | - Peter G Kerr
- Department of Nephrology, Monash Health, Melbourne, Australia.,Center for Inflammatory Diseases, Monash University, Melbourne, Australia
| | - Kate M Denton
- Cardiovascular Program, Monash Biomedicine Discovery Institute and Department of Physiology, Monash University, Melbourne, Australia
| | - Luc Furic
- Prostate Cancer Translational Research Laboratory, Peter MacCallum Cancer Centre.,Sir Peter MacCallum Department of Oncology, University of Melbourne, Australia.,Cancer Program, Biomedicine Discovery Institute and Department of Anatomy and Developmental Biology, Monash University, Melbourne, Australia
| | - Tobias B Huber
- III. Department of Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - David J Nikolic-Paterson
- Department of Nephrology, Monash Health, Melbourne, Australia.,Center for Inflammatory Diseases, Monash University, Melbourne, Australia
| | - John F Bertram
- Development and Stem Cells Program, Monash Biomedicine Discovery Institute and Department of Anatomy and Developmental Biology, Monash University, Melbourne, Australia
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41
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A bigenic mouse model of FSGS reveals perturbed pathways in podocytes, mesangial cells and endothelial cells. PLoS One 2019; 14:e0216261. [PMID: 31461442 PMCID: PMC6713350 DOI: 10.1371/journal.pone.0216261] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2019] [Accepted: 08/12/2019] [Indexed: 11/24/2022] Open
Abstract
Focal segmental glomerulosclerosis is a major cause of end stage renal disease. Many patients prove unresponsive to available therapies. An improved understanding of the molecular basis of the disease process could provide insights leading to novel therapeutic approaches. In this study we carried out an RNA-seq analysis of the altered gene expression patterns of podocytes, mesangial cells and glomerular endothelial cells of the bigenic Cd2ap+/-, Fyn-/- mutant mouse model of FSGS. In the podocytes we observed upregulation of many genes related to the Tgfβ family/pathway, including Gdnf, Tgfβ1, Tgfβ2, Snai2, Vegfb, Bmp4, and Tnc. The mutant podocytes also showed upregulation of Acta2, a marker of smooth muscle and associated with myofibroblasts, which are implicated in driving fibrosis. GO analysis of the podocyte upregulated genes identified elevated protein kinase activity, increased expression of growth factors, and negative regulation of cell adhesion, perhaps related to the observed podocyte loss. Both podocytes and mesangial cells showed strong upregulation of aldehyde dehydrogenase genes involved in the synthesis of retinoic acid. Similarly, the Cd2ap+/-, Fyn-/- mesangial cells, as well as podocytes in other genetic models, and the glomeruli of human FSGS patients, all show upregulation of the serine protease Prss23, with the common thread suggesting important functionality. Another gene with strong upregulation in the Cd2ap+/-, Fyn-/- mutant mesangial cells as well as multiple other mutant mouse models of FSGS was thrombospondin, which activates the secreted inactive form of Tgfβ. The Cd2ap+/-, Fyn-/- mutant endothelial cells showed elevated expression of genes involved in cell proliferation, angioblast migration, angiogenesis, and neovasculature, all consistent with the formation of new blood vessels in the diseased glomerulus. The resulting global definition of the perturbed molecular pathways in the three major cell types of the mutant glomerulus provide deeper understanding of the molecular pathogenic pathways.
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Reichelt-Wurm S, Wirtz T, Chittka D, Lindenmeyer M, Reichelt RM, Beck S, Politis P, Charonis A, Kretz M, Huber TB, Liu S, Banas B, Banas MC. Glomerular expression pattern of long non-coding RNAs in the type 2 diabetes mellitus BTBR mouse model. Sci Rep 2019; 9:9765. [PMID: 31278342 PMCID: PMC6611801 DOI: 10.1038/s41598-019-46180-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2018] [Accepted: 06/11/2019] [Indexed: 11/09/2022] Open
Abstract
The prevalence of type 2 diabetes mellitus (T2DM) and by association diabetic nephropathy (DN) will continuously increase in the next decades. Nevertheless, the underlying molecular mechanisms are largely unknown and studies on the role of new actors like long non-coding RNAs (lncRNAs) barely exist. In the present study, the inherently insulin-resistant mouse strain "black and tan, brachyuric" (BTBR) served as T2DM model. While wild-type mice do not exhibit pathological changes, leptin-deficient diabetic animals develop a severe T2DM accompanied by a DN, which closely resembles the human phenotype. We analyzed the glomerular expression of lncRNAs from wild-type and diabetic BTBR mice (four, eight, 16, and 24 weeks) applying the "GeneChip Mouse Whole Transcriptome 1.0 ST" array. This microarray covered more lncRNA gene loci than any other array before. Over the observed time, our data revealed differential expression patterns of 1746 lncRNAs, which markedly differed from mRNAs. We identified protein-coding and non-coding genes, that were not only co-located but also co-expressed, indicating a potentially cis-acting function of these lncRNAs. In vitro-experiments strongly suggested a cell-specific expression of these lncRNA-mRNA-pairs. Additionally, protein-coding genes, being associated with significantly regulated lncRNAs, were enriched in various biological processes and pathways, that were strongly linked to diabetes.
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Affiliation(s)
| | - Tobias Wirtz
- Department of Nephrology, University Hospital Regensburg, Regensburg, Germany
| | - Dominik Chittka
- Department of Nephrology, University Hospital Regensburg, Regensburg, Germany
| | - Maja Lindenmeyer
- Nephrological Center, Medical Clinic and Policlinic IV, University Hospital of Munich, Munich, Germany.,III. Department of Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Robert M Reichelt
- Department of Biochemistry, Genetics and Microbiology, Institute of Microbiology, University of Regensburg, Regensburg, Germany
| | - Sebastian Beck
- Department of Nephrology, University Hospital Regensburg, Regensburg, Germany
| | - Panagiotis Politis
- Center for Basic Research, Biomedical Research Foundation of the Academy of Athens, Athens, Greece
| | - Aristidis Charonis
- Center for Clinical, Experimental Surgery and Translational Research, Biomedical Research Foundation of the Academy of Athens, Athens, Greece
| | - Markus Kretz
- Institute of Biochemistry, Genetics and Microbiology, University of Regensburg, Regensburg, Germany
| | - Tobias B Huber
- III. Department of Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Shuya Liu
- III. Department of Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Bernhard Banas
- Department of Nephrology, University Hospital Regensburg, Regensburg, Germany
| | - Miriam C Banas
- Department of Nephrology, University Hospital Regensburg, Regensburg, Germany
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Boehm M, Bukosza EN, Huttary N, Herzog R, Aufricht C, Kratochwill K, Gebeshuber CA. A systems pharmacology workflow with experimental validation to assess the potential of anakinra for treatment of focal and segmental glomerulosclerosis. PLoS One 2019; 14:e0214332. [PMID: 30921378 PMCID: PMC6438574 DOI: 10.1371/journal.pone.0214332] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2018] [Accepted: 03/11/2019] [Indexed: 12/20/2022] Open
Abstract
Focal and Segmental Glomerulosclerosis (FSGS) is a severe glomerulopathy that frequently leads to end stage renal disease. Only a subset of patients responds to current therapies, making it important to identify alternative therapeutic options. The interleukin (IL)-1 receptor antagonist anakinra is beneficial in several diseases with renal involvement. Here, we evaluated the potential of anakinra for FSGS treatment. Molecular process models obtained from scientific literature data were used to build FSGS pathology and anakinra mechanism of action models by exploiting information on protein interactions. These molecular models were compared by statistical interference analysis and expert based molecular signature matching. Experimental validation was performed in Adriamycin- and lipopolysaccharide (LPS)-induced nephropathy mouse models. Interference analysis (containing 225 protein coding genes and 8 molecular process segments) of the FSGS molecular pathophysiology model with the drug mechanism of action of anakinra identified a statistically significant overlap with 43 shared molecular features that were enriched in pathways relevant in FSGS, such as plasminogen activating cascade, inflammation and apoptosis. Expert adjudication of molecular signature matching, focusing on molecular process segments did not suggest a high therapeutic potential of anakinra in FSGS. In line with this, experimental validation did not result in altered proteinuria or significant changes in expression of the FSGS-relevant genes COL1A1 and NPHS1. In summary, an integrated bioinformatic and experimental workflow showed that FSGS relevant molecular processes can be significantly affected by anakinra beyond the direct drug target IL-1 receptor type 1 (IL1R1) context but might not counteract central pathophysiology processes in FSGS. Anakinra is therefore not suggested for extended preclinical trials.
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Affiliation(s)
- Michael Boehm
- Division of Pediatric Nephrology and Gastroenterology, Department of Pediatrics and Adolescent Medicine, Medical University of Vienna, Vienna, Austria
| | - Eva Nora Bukosza
- Institute of Pathophysiology, Semmelweis University Budapest, Budapest, Hungary
| | - Nicole Huttary
- Clinical Institute of Pathology, Medical University of Vienna, Vienna, Austria
| | - Rebecca Herzog
- Division of Pediatric Nephrology and Gastroenterology, Department of Pediatrics and Adolescent Medicine, Medical University of Vienna, Vienna, Austria
- Christian Doppler Laboratory for Molecular Stress Research in Peritoneal Dialysis, Department of Pediatrics and Adolescent Medicine, Medical University of Vienna, Vienna, Austria
| | - Christoph Aufricht
- Division of Pediatric Nephrology and Gastroenterology, Department of Pediatrics and Adolescent Medicine, Medical University of Vienna, Vienna, Austria
| | - Klaus Kratochwill
- Division of Pediatric Nephrology and Gastroenterology, Department of Pediatrics and Adolescent Medicine, Medical University of Vienna, Vienna, Austria
- Christian Doppler Laboratory for Molecular Stress Research in Peritoneal Dialysis, Department of Pediatrics and Adolescent Medicine, Medical University of Vienna, Vienna, Austria
- * E-mail: (KK); (CAG)
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44
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Tang J, Yao D, Yan H, Chen X, Wang L, Zhan H. The Role of MicroRNAs in the Pathogenesis of Diabetic Nephropathy. Int J Endocrinol 2019; 2019:8719060. [PMID: 31885563 PMCID: PMC6914872 DOI: 10.1155/2019/8719060] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/06/2019] [Revised: 10/07/2019] [Accepted: 10/22/2019] [Indexed: 02/08/2023] Open
Abstract
Diabetic nephropathy (DN) is one of the most common microvascular complications in diabetic patients; it is also an important cause of renal dysfunction, renal fibrosis, and end-stage renal disease. Unfortunately, the pathogenesis of DN is complex and has not yet been fully elucidated; hence, the pathogenesis of DN to determine effective treatments of crucial importance is deeply explored. Early DN research focuses on hemodynamic changes and metabolic disorders, and recent studies have shown the regulatory role of microRNAs (miRNAs) in genes, which may be a new diagnostic marker and therapeutic target for diabetic nephropathy. In this review, we summarize the recent advances in the clinical value and molecular mechanisms of miRNAs in DN, providing new ideas for the diagnosis and treatment of DN.
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Affiliation(s)
- Jian Tang
- Hospital of Chengdu University of Traditional Chinese Medicine, Chengdu 610075, Sichuan, China
| | - Deyi Yao
- Chengdu University of Traditional Chinese Medicine, Chengdu 610075, Sichuan, China
| | - Haiying Yan
- Chengdu University of Traditional Chinese Medicine, Chengdu 610075, Sichuan, China
| | - Xing Chen
- Chengdu University of Traditional Chinese Medicine, Chengdu 610075, Sichuan, China
| | - Linjia Wang
- Chengdu University of Traditional Chinese Medicine, Chengdu 610075, Sichuan, China
| | - Huakui Zhan
- Hospital of Chengdu University of Traditional Chinese Medicine, Chengdu 610075, Sichuan, China
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45
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Schell C, Sabass B, Helmstaedter M, Geist F, Abed A, Yasuda-Yamahara M, Sigle A, Maier JI, Grahammer F, Siegerist F, Artelt N, Endlich N, Kerjaschki D, Arnold HH, Dengjel J, Rogg M, Huber TB. ARP3 Controls the Podocyte Architecture at the Kidney Filtration Barrier. Dev Cell 2018; 47:741-757.e8. [PMID: 30503751 PMCID: PMC6302147 DOI: 10.1016/j.devcel.2018.11.011] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2017] [Revised: 09/03/2018] [Accepted: 11/01/2018] [Indexed: 12/20/2022]
Abstract
Podocytes, highly specialized epithelial cells, build the outer part of the kidney filtration barrier and withstand high mechanical forces through a complex network of cellular protrusions. Here, we show that Arp2/3-dependent actin polymerization controls actomyosin contractility and focal adhesion maturation of podocyte protrusions and thereby regulates formation, maintenance, and capacity to adapt to mechanical requirements of the filtration barrier. We find that N-WASP-Arp2/3 define the development of complex arborized podocyte protrusions in vitro and in vivo. Loss of dendritic actin networks results in a pronounced activation of the actomyosin cytoskeleton and the generation of over-maturated but less efficient adhesion, leading to detachment of podocytes. Our data provide a model to explain podocyte protrusion morphology and their mechanical stability based on a tripartite relationship between actin polymerization, contractility, and adhesion. ARP3-dependent actin assembly is required for podocyte process formation Arp2/3 thereby links process formation, podocyte adhesion and mechano-adaptation Arp2/3 function is regulated by a reciprocal interplay with actomyosin
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Affiliation(s)
- Christoph Schell
- Institute of Surgical Pathology, Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg 79106, Germany; Department of Medicine IV, Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg 79106, Germany; Berta-Ottenstein Programme, Faculty of Medicine, University of Freiburg, Freiburg 79106, Germany
| | - Benedikt Sabass
- Institute of Complex Systems-2, Forschungszentrum Jülich, Jülich 52428, Germany
| | - Martin Helmstaedter
- Department of Medicine IV, Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg 79106, Germany
| | - Felix Geist
- Department of Medicine IV, Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg 79106, Germany
| | - Ahmed Abed
- Department of Medicine IV, Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg 79106, Germany
| | - Mako Yasuda-Yamahara
- Department of Medicine IV, Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg 79106, Germany; Department of Medicine, Shiga University of Medical Science, Otsu, Shiga 520-2192, Japan
| | - August Sigle
- Department of Medicine IV, Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg 79106, Germany
| | - Jasmin I Maier
- Institute of Surgical Pathology, Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg 79106, Germany; Department of Medicine IV, Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg 79106, Germany
| | - Florian Grahammer
- Department of Medicine IV, Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg 79106, Germany; III. Department of Medicine, University Medical Center Hamburg-Eppendorf, Hamburg 20246, Germany
| | - Florian Siegerist
- Department of Anatomy and Cell Biology, University Medicine Greifswald, Greifswald 17487, Germany
| | - Nadine Artelt
- Department of Anatomy and Cell Biology, University Medicine Greifswald, Greifswald 17487, Germany
| | - Nicole Endlich
- Department of Anatomy and Cell Biology, University Medicine Greifswald, Greifswald 17487, Germany
| | | | - Hans-Henning Arnold
- Cell and Molecular Biology, Technical University of Braunschweig, Braunschweig 38106, Germany
| | - Jörn Dengjel
- BIOSS Center for Biological Signaling Studies, Albert-Ludwigs-University Freiburg, Freiburg 79106, Germany; Department of Biology, University of Fribourg, Fribourg 1700, Switzerland; Department of Dermatology, Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg 79104, Germany
| | - Manuel Rogg
- Department of Medicine IV, Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg 79106, Germany
| | - Tobias B Huber
- Department of Medicine IV, Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg 79106, Germany; III. Department of Medicine, University Medical Center Hamburg-Eppendorf, Hamburg 20246, Germany; BIOSS Center for Biological Signaling Studies, Albert-Ludwigs-University Freiburg, Freiburg 79106, Germany.
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46
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Okabe M, Motojima M, Miyazaki Y, Pastan I, Yokoo T, Matsusaka T. Global polysome analysis of normal and injured podocytes. Am J Physiol Renal Physiol 2018; 316:F241-F252. [PMID: 30379099 DOI: 10.1152/ajprenal.00115.2018] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Podocyte injury is a key event for progressive renal failure. We have previously established a mouse model of inducible podocyte injury (NEP25) that progressively develops glomerulosclerosis after immunotoxin injection. We performed polysome analysis of intact and injured podocytes utilizing the NEP25 and RiboTag transgenic mice, in which a hemagglutinin tag is attached to ribosomal protein L22 selectively in podocytes. Podocyte-specific polysomes were successfully obtained by immunoprecipitation with an antihemagglutinin antibody from glomerular homogenate and analyzed using a microarray. Compared with glomerular cells, 353 genes were highly expressed and enriched in podocytes; these included important podocyte genes and also heretofore uncharacterized genes, such as Dach1 and Foxd2. Podocyte injury by immunotoxin induced many genes to be upregulated, including inflammation-related genes despite no infiltration of inflammatory cells in the glomeruli. MafF and Egr-1, which structurally have the potential to antagonize MafB and WT1, respectively, were rapidly and markedly increased in injured podocytes before MafB and WT1 were decreased. We demonstrated that Maff and Egr1 knockdown increased the MafB targets Nphs2 and Ptpro and the WT1 targets Ptpro, Nxph3, and Sulf1, respectively. This indicates that upregulated MafF and Egr-1 may promote deterioration of podocytes by antagonizing MafB and WT1. Our systematic microarray study of the heretofore undescribed behavior of podocyte genes may open new insights into the understanding of podocyte pathophysiology.
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Affiliation(s)
- 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
| | - Masaru Motojima
- Department of Clinical Pharmacology, Tokai University School of Medicine , Isehara , Japan
| | - Yoichi Miyazaki
- 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
| | - Takashi Yokoo
- Division of Nephrology and Hypertension, Department of Internal Medicine, The Jikei University School of Medicine , Tokyo , 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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47
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Rennert L, Zschiedrich S, Sandner L, Hartleben B, Cicko S, Ayata CK, Meyer C, Zech A, Zeiser R, Huber TB, Idzko M, Grahammer F. P2Y2R Signaling Is Involved in the Onset of Glomerulonephritis. Front Immunol 2018; 9:1589. [PMID: 30061884 PMCID: PMC6054981 DOI: 10.3389/fimmu.2018.01589] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2018] [Accepted: 06/27/2018] [Indexed: 12/19/2022] Open
Abstract
Endogenously released adenosine-5’-triphosphate (ATP) is a key regulator of physiological function and inflammatory responses in the kidney. Genetic or pharmacological inhibition of purinergic receptors has been linked to attenuation of inflammatory disorders and hence constitutes promising new avenues for halting and reverting inflammatory renal diseases. However, the involvement of purinergic receptors in glomerulonephritis (GN) has only been incompletely mapped. Here, we demonstrate that induction of GN in an experimental antibody-mediated GN model results in a significant increase of urinary ATP-levels and an upregulation of P2Y2R expression in resident kidney cells as well as infiltrating leukocytes pointing toward a possible role of the ATP/P2Y2R-axis in glomerular disease initiation. In agreement, decreasing extracellular ATP-levels or inhibition of P2R during induction of antibody-mediated GN leads to a reduction in all cardinal features of GN such as proteinuria, glomerulosclerosis, and renal failure. The specific involvement of P2Y2R could be further substantiated by demonstrating the protective effect of the lack of P2Y2R in antibody-mediated GN. To systematically differentiate between the function of P2Y2R on resident renal cells versus infiltrating leukocytes, we performed bone marrow-chimera experiments revealing that P2Y2R on hematopoietic cells is the main driver of the ATP/P2Y2R-mediated disease progression in antibody-mediated GN. Thus, these data unravel an important pro-inflammatory role for P2Y2R in the pathogenesis of GN.
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Affiliation(s)
- Laura Rennert
- Department of Medicine IV, Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Stefan Zschiedrich
- Department of Medicine IV, Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Lukas Sandner
- Department of Medicine IV, Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany.,Department of Pneumology, University Medical Center Freiburg, Freiburg, Germany
| | - Björn Hartleben
- Department of Medicine IV, Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Sanja Cicko
- Department of Pneumology, University Medical Center Freiburg, Freiburg, Germany
| | - Cemil Korcan Ayata
- Department of Pneumology, University Medical Center Freiburg, Freiburg, Germany
| | - Charlotte Meyer
- Department of Pneumology, University Medical Center Freiburg, Freiburg, Germany
| | - Andreas Zech
- Department of Pneumology, University Medical Center Freiburg, Freiburg, Germany
| | - Robert Zeiser
- Department of Hematology, Oncology and Stem Cell Transplantation, University Medical Center Freiburg, Freiburg, Germany
| | - Tobias B Huber
- Department of Medicine IV, Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany.,III. Department of Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany.,BIOSS Center for Biological Signalling Studies, Albert-Ludwigs-University, Freiburg, Germany
| | - Marco Idzko
- Department of Pneumology, University Medical Center Freiburg, Freiburg, Germany.,Division of Pulmonology, Department of Medicine II, Medical University Vienna, Vienna, Austria
| | - Florian Grahammer
- Department of Medicine IV, Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany.,III. Department of Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
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48
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Yasuda-Yamahara M, Rogg M, Yamahara K, Maier JI, Huber TB, Schell C. AIF1L regulates actomyosin contractility and filopodial extensions in human podocytes. PLoS One 2018; 13:e0200487. [PMID: 30001384 PMCID: PMC6042786 DOI: 10.1371/journal.pone.0200487] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2018] [Accepted: 06/27/2018] [Indexed: 11/17/2022] Open
Abstract
Podocytes are highly-specialized epithelial cells essentially required for the generation and the maintenance of the kidney filtration barrier. This elementary function is directly based on an elaborated cytoskeletal apparatus establishing a complex network of primary and secondary processes. Here, we identify the actin-bundling protein allograft-inflammatory-inhibitor 1 like (AIF1L) as a selectively expressed podocyte protein in vivo. We describe the distinct subcellular localization of AIF1L to actin stress fibers, focal adhesion complexes and the nuclear compartment of podocytes in vitro. Genetic deletion of AIF1L in immortalized human podocytes resulted in an increased formation of filopodial extensions and decreased actomyosin contractility. By the use of SILAC based quantitative proteomics analysis we describe the podocyte specific AIF1L interactome and identify several components of the actomyosin machinery such as MYL9 and UNC45A as potential AIF1L interaction partners. Together, these findings indicate an involvement of AIF1L in the stabilization of podocyte morphology by titrating actomyosin contractility and membrane dynamics.
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Affiliation(s)
- Mako Yasuda-Yamahara
- Department of Medicine IV, Medical Center – University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
- Department of Medicine, Shiga University of Medical Science, Otsu, Shiga, Japan
| | - Manuel Rogg
- Department of Medicine IV, Medical Center – University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Kosuke Yamahara
- Department of Medicine IV, Medical Center – University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
- Department of Medicine, Shiga University of Medical Science, Otsu, Shiga, Japan
| | - Jasmin I. Maier
- Department of Medicine IV, Medical Center – University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
- Institute for Surgical Pathology, University Medical Center Freiburg, Freiburg, Germany
| | - Tobias B. Huber
- Department of Medicine IV, Medical Center – University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
- BIOSS Center for Biological Signalling Studies, Albert-Ludwigs-University Freiburg, Freiburg, Germany
- Department of Medicine III, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
- * E-mail:
| | - Christoph Schell
- Department of Medicine IV, Medical Center – University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
- Institute for Surgical Pathology, University Medical Center Freiburg, Freiburg, Germany
- Berta-Ottenstein Programme, Faculty of Medicine, University of Freiburg, Freiburg, Germany
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49
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Fu J, Wei C, Zhang W, Schlondorff D, Wu J, Cai M, He W, Baron MH, Chuang PY, Liu Z, He JC, Lee K. Gene expression profiles of glomerular endothelial cells support their role in the glomerulopathy of diabetic mice. Kidney Int 2018; 94:326-345. [PMID: 29861058 PMCID: PMC6054896 DOI: 10.1016/j.kint.2018.02.028] [Citation(s) in RCA: 58] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2017] [Revised: 02/06/2018] [Accepted: 02/15/2018] [Indexed: 01/15/2023]
Abstract
Endothelial dysfunction promotes the pathogenesis of diabetic nephropathy (DN), which is considered to be an early event in disease progression. However, the molecular changes associated with glomerular endothelial cell (GEC) injury in early DN are not well defined. Most gene expression studies have relied on the indirect assessment of GEC injury from isolated glomeruli or renal cortices. Here, we present transcriptomic analysis of isolated GECs, using streptozotocin-induced diabetic wildtype (STZ-WT) and diabetic eNOS-null (STZ-eNOS-/-) mice as models of mild and advanced DN, respectively. GECs of both models in comparison to their respective nondiabetic controls showed significant alterations in the regulation of apoptosis, oxidative stress, and proliferation. The extent of these changes was greater in STZ-eNOS-/- than in STZ-WT GECs. Additionally, genes in STZ-eNOS-/- GECs indicated further dysregulation in angiogenesis and epigenetic regulation. Moreover, a biphasic change in the number of GECs, characterized by an initial increase and subsequent decrease over time, was observed only in STZ-eNOS-/- mice. This is consistent with an early compensatory angiogenic process followed by increased apoptosis, leading to an overall decrease in GEC survival in DN progression. From the genes altered in angiogenesis in STZ-eNOS-/- GECs, we identified potential candidate genes, Lrg1 and Gpr56, whose function may augment diabetes-induced angiogenesis. Thus, our results support a role for GEC in DN by providing direct evidence for alterations of GEC gene expression and molecular pathways. Candidate genes of specific pathways, such as Lrg1 and Gpr56, can be further explored for potential therapeutic targeting to mitigate the initiation and progression of DN.
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Affiliation(s)
- Jia Fu
- Division of Nephrology, Department of Medicine, Icahn School of Medicine at Mount Sinai, New York, New York, USA; National Clinical Research Center of Kidney Diseases, Jinling Hospital, Nanjing University School of Medicine, Nanjing, China
| | - Chengguo Wei
- Division of Nephrology, Department of Medicine, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - Weijia Zhang
- Division of Nephrology, Department of Medicine, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - Detlef Schlondorff
- Division of Nephrology, Department of Medicine, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - Jinshan Wu
- Division of Nephrology, Department of Medicine, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - Minchao Cai
- Division of Nephrology, Department of Medicine, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - Wu He
- Flow Cytometry Shared Resource Facility, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - Margaret H Baron
- Division of Hematology and Medical Oncology, Department of Medicine, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - Peter Y Chuang
- Division of Nephrology, Department of Medicine, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - Zhihong Liu
- National Clinical Research Center of Kidney Diseases, Jinling Hospital, Nanjing University School of Medicine, Nanjing, China.
| | - John Cijiang He
- Division of Nephrology, Department of Medicine, Icahn School of Medicine at Mount Sinai, New York, New York, USA; Renal Program, James J. Peters VA Medical Center at Bronx, New York, New York, USA.
| | - Kyung Lee
- Division of Nephrology, Department of Medicine, Icahn School of Medicine at Mount Sinai, New York, New York, USA.
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50
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Karaiskos N, Rahmatollahi M, Boltengagen A, Liu H, Hoehne M, Rinschen M, Schermer B, Benzing T, Rajewsky N, Kocks C, Kann M, Müller RU. A Single-Cell Transcriptome Atlas of the Mouse Glomerulus. J Am Soc Nephrol 2018; 29:2060-2068. [PMID: 29794128 DOI: 10.1681/asn.2018030238] [Citation(s) in RCA: 125] [Impact Index Per Article: 20.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2018] [Accepted: 04/28/2018] [Indexed: 11/03/2022] Open
Abstract
Background Three different cell types constitute the glomerular filter: mesangial cells, endothelial cells, and podocytes. However, to what extent cellular heterogeneity exists within healthy glomerular cell populations remains unknown.Methods We used nanodroplet-based highly parallel transcriptional profiling to characterize the cellular content of purified wild-type mouse glomeruli.Results Unsupervised clustering of nearly 13,000 single-cell transcriptomes identified the three known glomerular cell types. We provide a comprehensive online atlas of gene expression in glomerular cells that can be queried and visualized using an interactive and freely available database. Novel marker genes for all glomerular cell types were identified and supported by immunohistochemistry images obtained from the Human Protein Atlas. Subclustering of endothelial cells revealed a subset of endothelium that expressed marker genes related to endothelial proliferation. By comparison, the podocyte population appeared more homogeneous but contained three smaller, previously unknown subpopulations.Conclusions Our study comprehensively characterized gene expression in individual glomerular cells and sets the stage for the dissection of glomerular function at the single-cell level in health and disease.
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Affiliation(s)
- Nikos Karaiskos
- Systems Biology of Gene Regulatory Elements, Berlin Institute for Medical Systems Biology, Max Delbrück Center for Molecular Medicine in the Helmholtz Association, Berlin, Germany
| | | | - Anastasiya Boltengagen
- Systems Biology of Gene Regulatory Elements, Berlin Institute for Medical Systems Biology, Max Delbrück Center for Molecular Medicine in the Helmholtz Association, Berlin, Germany
| | - Haiyue Liu
- Systems Biology of Gene Regulatory Elements, Berlin Institute for Medical Systems Biology, Max Delbrück Center for Molecular Medicine in the Helmholtz Association, Berlin, Germany
| | - Martin Hoehne
- Department II of Internal Medicine and Center for Molecular Medicine Cologne
| | - Markus Rinschen
- Department II of Internal Medicine and Center for Molecular Medicine Cologne.,Scripps Center for Metabolomics and Mass Spectrometry, The Scripps Research Institute, San Diego, California
| | - Bernhard Schermer
- Department II of Internal Medicine and Center for Molecular Medicine Cologne.,Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases, and.,Systems Biology of Ageing Cologne, University of Cologne, Cologne, Germany; and
| | - Thomas Benzing
- Department II of Internal Medicine and Center for Molecular Medicine Cologne.,Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases, and.,Systems Biology of Ageing Cologne, University of Cologne, Cologne, Germany; and
| | - Nikolaus Rajewsky
- Systems Biology of Gene Regulatory Elements, Berlin Institute for Medical Systems Biology, Max Delbrück Center for Molecular Medicine in the Helmholtz Association, Berlin, Germany
| | - Christine Kocks
- Systems Biology of Gene Regulatory Elements, Berlin Institute for Medical Systems Biology, Max Delbrück Center for Molecular Medicine in the Helmholtz Association, Berlin, Germany;
| | - Martin Kann
- Department II of Internal Medicine and Center for Molecular Medicine Cologne
| | - Roman-Ulrich Müller
- Department II of Internal Medicine and Center for Molecular Medicine Cologne, .,Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases, and.,Systems Biology of Ageing Cologne, University of Cologne, Cologne, Germany; and
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