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Naas S, Krüger R, Knaup KX, Naas J, Grampp S, Schiffer M, Wiesener M, Schödel J. Hypoxia controls expression of kidney-pathogenic MUC1 variants. Life Sci Alliance 2023; 6:e202302078. [PMID: 37316299 PMCID: PMC10267510 DOI: 10.26508/lsa.202302078] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2023] [Revised: 05/31/2023] [Accepted: 06/01/2023] [Indexed: 06/16/2023] Open
Abstract
The interplay between genetic and environmental factors influences the course of chronic kidney disease (CKD). In this context, genetic alterations in the kidney disease gene MUC1 (Mucin1) predispose to the development of CKD. These variations comprise the polymorphism rs4072037, which alters splicing of MUC1 mRNA, the length of a region with variable number of tandem repeats (VNTR), and rare autosomal-dominant inherited dominant-negative mutations in or 5' to the VNTR that causes autosomal dominant tubulointerstitial kidney disease (ADTKD-MUC1). As hypoxia plays a pivotal role in states of acute and chronic kidney injury, we explored the effects of hypoxia-inducible transcription factors (HIF) on the expression of MUC1 and its pathogenic variants in isolated primary human renal tubular cells. We defined a HIF-binding DNA regulatory element in the promoter-proximal region of MUC1 from which hypoxia or treatment with HIF stabilizers, which were recently approved for an anti-anemic therapy in CKD patients, increased levels of wild-type MUC1 and the disease-associated variants. Thus, application of these compounds might exert unfavorable effects in patients carrying MUC1 risk variants.
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Affiliation(s)
- Stephanie Naas
- Department of Nephrology and Hypertension, Uniklinikum Erlangen und Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany
| | - René Krüger
- Department of Nephrology and Hypertension, Uniklinikum Erlangen und Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany
| | - Karl Xaver Knaup
- Department of Nephrology and Hypertension, Uniklinikum Erlangen und Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany
| | - Julia Naas
- Center for Integrative Bioinformatics Vienna (CIBIV), Max Perutz Labs, University of Vienna and Medical University of Vienna, Wien, Austria
| | - Steffen Grampp
- Department of Nephrology and Hypertension, Uniklinikum Erlangen und Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany
| | - Mario Schiffer
- Department of Nephrology and Hypertension, Uniklinikum Erlangen und Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany
| | - Michael Wiesener
- Department of Nephrology and Hypertension, Uniklinikum Erlangen und Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany
| | - Johannes Schödel
- Department of Nephrology and Hypertension, Uniklinikum Erlangen und Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany
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2
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Torsello B, De Marco S, Bombelli S, Cifola I, Morabito I, Invernizzi L, Meregalli C, Zucchini N, Strada G, Perego RA, Bianchi C. High glucose induces an activated state of partial epithelial-mesenchymal transition in human primary tubular cell cultures. PLoS One 2023; 18:e0279655. [PMID: 36827456 PMCID: PMC9956654 DOI: 10.1371/journal.pone.0279655] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2022] [Accepted: 12/12/2022] [Indexed: 02/26/2023] Open
Abstract
Tubulointerstitial fibrosis is observed in diabetic nephropathy. It is still debated whether tubular cells, undergoing epithelial-mesenchymal transition (EMT) in high glucose (HG) conditions, may contribute to interstitial fibrosis development. In this study, we investigated the phenotypic and molecular EMT-like changes and the alteration of inflammatory and fibrogenic secretome induced by HG in human primary tubular cell cultures. Taking advantage of this in vitro cell model composed of proximal and distal tubular cells, we showed that HG-treated tubular cells acquired a fibroblast-like morphology with increased cytoplasmic stress fibers, maintaining the expression of the epithelial markers specific of proximal and distal tubular cells. HG increased Snail1, miRNA210 and Vimentin mesenchymal markers, decreased N-cadherin expression and migration ability of primary tubular cells, while E-cadherin expression and focal adhesion distribution were not affected. Furthermore, HG treatment of tubular cells altered the inflammatory cytokine secretion creating a secretome able to enhance the proliferation and migration of fibroblasts. Our findings show that HG promotes an activated state of partial EMT in human tubular primary cells and induces a pro-inflammatory and pro-fibrogenic microenvironment, supporting the active role of tubular cells in diabetic nephropathy onset.
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Affiliation(s)
- Barbara Torsello
- School of Medicine and Surgery, University of Milano-Bicocca, Monza, Italy
| | - Sofia De Marco
- School of Medicine and Surgery, University of Milano-Bicocca, Monza, Italy
| | - Silvia Bombelli
- School of Medicine and Surgery, University of Milano-Bicocca, Monza, Italy
| | - Ingrid Cifola
- Institute for Biomedical Technologies (ITB), National Research Council (CNR), Segrate, Italy
| | - Ivana Morabito
- School of Medicine and Surgery, University of Milano-Bicocca, Monza, Italy
| | - Lara Invernizzi
- School of Medicine and Surgery, University of Milano-Bicocca, Monza, Italy
| | - Chiara Meregalli
- School of Medicine and Surgery, University of Milano-Bicocca, Monza, Italy
| | - Nicola Zucchini
- Pathology Unit, Azienda Socio Sanitaria Territoriale (ASST) Monza, San Gerardo Hospital, Monza, Italy
| | - Guido Strada
- ASST North Milan, Bassini Hospital, Cinisello Balsamo, Italy
| | - Roberto A. Perego
- School of Medicine and Surgery, University of Milano-Bicocca, Monza, Italy
| | - Cristina Bianchi
- School of Medicine and Surgery, University of Milano-Bicocca, Monza, Italy
- * E-mail:
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3
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Yealland G, Jevtic M, Eckardt KU, Schueler M. Modeling ciliopathies in patient-derived primary cells. Methods Cell Biol 2023; 176:139-158. [PMID: 37164535 DOI: 10.1016/bs.mcb.2023.02.016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/29/2023]
Abstract
Ciliopathies comprise a group of inherited diseases caused by mutations in genes encoding proteins that localize to cilia or centrosomes. They afflict multiple organs and are one of the most frequent monogenic causes of kidney failure in adults, adolescents and children. Primary cilia play diverse roles in cell signaling, cell cycle regulation, planar cell polarity and mechanosensing. The use of patient-derived cells possessing endogenous disease causing mutations enables the study of these processes and their dysregulation in disease. Here we describe methods to cultivate patient-derived dermal fibroblast and renal epithelial cells isolated from urine. Fibroblasts are highly robust, long-lived, and easy to culture cells in which ciliary assembly can be easily induced. Similarly, the ability to acquire and culture ciliated renal epithelial cells without patient-invasive-intervention holds great potential to further our understanding of ciliopathies. In addition to monolayer cultures, we also detail the formation of three-dimensional renal-epithelial organoids-so-called tubuloids-that demonstrate epithelial-polarization and transepithelial transport activities like those seen in vivo renal-tubules. These in vitro models are powerful tools to investigate the underlying disease mechanisms of human ciliopathies that can be employed without the need for heavy-handed genetic or molecular manipulations.
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4
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Parigoris E, Lee JH, Liu AY, Zhao X, Takayama S. Extended longevity geometrically-inverted proximal tubule organoids. Biomaterials 2022; 290:121828. [PMID: 36215909 PMCID: PMC10693433 DOI: 10.1016/j.biomaterials.2022.121828] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2022] [Revised: 09/11/2022] [Accepted: 09/24/2022] [Indexed: 01/22/2023]
Abstract
This study reports the cellular self-organization of primary human renal proximal tubule epithelial cells (RPTECs) around a minimal Matrigel scaffold to produce basal-in and apical-out proximal tubule organoids (tubuloids). These tubuloids are produced and maintained in hanging drop cultures for 90+ days, the longest such culture of any kind reported to date. The tubuloids upregulate maturity markers, such as aquaporin-1 (AQP1) and megalin (LRP2), and exhibit less mesenchymal and proliferation markers, such as vimentin and Ki67, compared to 2D cultures. They also experience changes over time as revealed by a comparison of gene expression patterns of cells in 2D culture and in day 31 and day 67 tubuloids. Gene expression analysis and immunohistochemistry reveal an increase in the expression of megalin, an endocytic receptor that can directly bind and uptake protein or potentially assist protein uptake. The tubuloids, including day 90 tubuloids, uptake fluorescent albumin and reveal punctate fluorescent patterns, suggesting functional endocytic uptake through these receptors. Furthermore, the tubuloids release kidney injury molecule-1 (KIM-1), a common biomarker for kidney injury, when exposed to albumin in both dose- and time-dependent manners. While this study focuses on potential applications for modeling proteinuric kidney disease, the tubuloids may have broad utility for studies where apical proximal tubule cell access is required.
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Affiliation(s)
- Eric Parigoris
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University School of Medicine, Atlanta, GA, United States; The Parker H. Petit Institute of Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, GA, United States
| | - Ji-Hoon Lee
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University School of Medicine, Atlanta, GA, United States; The Parker H. Petit Institute of Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, GA, United States
| | - Amy Yunfan Liu
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University School of Medicine, Atlanta, GA, United States; The Parker H. Petit Institute of Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, GA, United States
| | - Xueying Zhao
- Department of Physiology, Morehouse School of Medicine, Atlanta, GA, United States
| | - Shuichi Takayama
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University School of Medicine, Atlanta, GA, United States; The Parker H. Petit Institute of Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, GA, United States.
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5
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Protze J, Naas S, Krüger R, Stöhr C, Kraus A, Grampp S, Wiesener M, Schiffer M, Hartmann A, Wullich B, Schödel J. The renal cancer risk allele at 14q24.2 activates a novel hypoxia-inducible transcription factor-binding enhancer of DPF3 expression. J Biol Chem 2022; 298:101699. [PMID: 35148991 PMCID: PMC8897700 DOI: 10.1016/j.jbc.2022.101699] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2021] [Revised: 02/02/2022] [Accepted: 02/04/2022] [Indexed: 11/29/2022] Open
Abstract
Evolution of clear cell renal cell carcinoma is guided by dysregulation of hypoxia-inducible transcription factor (HIF) pathways following loss of the von Hippel-Lindau tumor suppressor protein. Renal cell carcinoma (RCC)-associated polymorphisms influence HIF–DNA interactions at enhancers of important oncogenes thereby modulating the risk of developing renal cancer. A strong signal of genome-wide association with RCC was determined for the single nucleotide polymorphism (SNP) rs4903064, located on chr14q.24.2 within an intron of DPF3, encoding for Double PHD Fingers 3, a member of chromatin remodeling complexes; however, it is unclear how the risk allele operates in renal cells. In this study, we used tissue specimens and primary renal cells from a large cohort of RCC patients to examine the function of this polymorphism. In clear cell renal cell carcinoma tissue, isolated tumor cells as well as in primary renal tubular cells, in which HIF was stabilized, we determined genotype-specific increases of DPF3 mRNA levels and identified that the risk SNP resides in an active enhancer region, creating a novel HIF-binding motif. We then confirmed allele-specific HIF binding to this locus using chromatin immunoprecipitation of HIF subunits. Consequentially, HIF-mediated DPF3 regulation was dependent on the presence of the risk allele. Finally, we show that DPF3 deletion in proximal tubular cells retarded cell growth, indicating potential roles for DPF3 in cell proliferation. Our analyses suggest that the HIF pathway differentially operates on a SNP-induced hypoxia-response element at 14q24.2, thereby affecting DPF3 expression, which increases the risk of developing renal cancer.
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Affiliation(s)
- Johanna Protze
- Department of Nephrology and Hypertension, Universitätsklinikum Erlangen und Friedrich-Alexander-Universität Erlangen-Nürnberg, Ulmenweg 18, 91054 Erlangen, Germany
| | - Stephanie Naas
- Department of Nephrology and Hypertension, Universitätsklinikum Erlangen und Friedrich-Alexander-Universität Erlangen-Nürnberg, Ulmenweg 18, 91054 Erlangen, Germany
| | - René Krüger
- Department of Nephrology and Hypertension, Universitätsklinikum Erlangen und Friedrich-Alexander-Universität Erlangen-Nürnberg, Ulmenweg 18, 91054 Erlangen, Germany
| | - Christine Stöhr
- Institute of Pathology, Universitätsklinikum Erlangen und Friedrich-Alexander-Universität Erlangen-Nürnberg, Krankenhausstraße 8-10, 91054 Erlangen, Germany
| | - Andre Kraus
- Department of Nephrology and Hypertension, Universitätsklinikum Erlangen und Friedrich-Alexander-Universität Erlangen-Nürnberg, Ulmenweg 18, 91054 Erlangen, Germany
| | - Steffen Grampp
- Department of Nephrology and Hypertension, Universitätsklinikum Erlangen und Friedrich-Alexander-Universität Erlangen-Nürnberg, Ulmenweg 18, 91054 Erlangen, Germany
| | - Michael Wiesener
- Department of Nephrology and Hypertension, Universitätsklinikum Erlangen und Friedrich-Alexander-Universität Erlangen-Nürnberg, Ulmenweg 18, 91054 Erlangen, Germany
| | - Mario Schiffer
- Department of Nephrology and Hypertension, Universitätsklinikum Erlangen und Friedrich-Alexander-Universität Erlangen-Nürnberg, Ulmenweg 18, 91054 Erlangen, Germany
| | - Arndt Hartmann
- Institute of Pathology, Universitätsklinikum Erlangen und Friedrich-Alexander-Universität Erlangen-Nürnberg, Krankenhausstraße 8-10, 91054 Erlangen, Germany; Comprehensive Cancer Center Erlangen-EMN (CCC ER-EMN), Erlangen, Germany
| | - Bernd Wullich
- Comprehensive Cancer Center Erlangen-EMN (CCC ER-EMN), Erlangen, Germany; Department of Urology and Pediatric Urology, Universitätsklinikum Erlangen und Friedrich-Alexander-Universität Erlangen-Nürnberg, Krankenhausstraße 12, 91054 Erlangen, Germany
| | - Johannes Schödel
- Department of Nephrology and Hypertension, Universitätsklinikum Erlangen und Friedrich-Alexander-Universität Erlangen-Nürnberg, Ulmenweg 18, 91054 Erlangen, Germany.
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Copur S, Rossing P, Afsar B, Sag AA, Siriopol D, Kuwabara M, Ortiz A, Kanbay M. A primer on metabolic memory: why existing diabesity treatments fail. Clin Kidney J 2021; 14:756-767. [PMID: 34512957 PMCID: PMC8422888 DOI: 10.1093/ckj/sfaa143] [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: 04/30/2020] [Indexed: 11/28/2022] Open
Abstract
Despite massive government and private sector investments into prevention of cardiovascular disease, diabetes mellitus and obesity, efforts have largely failed, and the burden of cost remains in the treatment of downstream morbidity and mortality, with overall stagnating outcomes. A new paradigm shift in the approach to these patients may explain why existing treatment strategies fail, and offer new treatment targets. This review aims to provide a clinician-centred primer on metabolic memory, defined as the sum of irreversible genetic, epigenetic, cellular and tissue-level alterations that occur with long-time exposure to metabolic derangements.
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Affiliation(s)
- Sidar Copur
- Department of Medicine, Koc University School of Medicine, Istanbul, Turkey
| | - Peter Rossing
- Steno Diabetes Center Copenhagen, University of Copenhagen, Copenhagen, Denmark
| | - Baris Afsar
- Department of Internal Medicine, Division of Nephrology, Suleyman Demirel University School of Medicine, Isparta, Turkey
| | - Alan A Sag
- Department of Radiology, Division of Vascular and Interventional Radiology, Duke University Medical Center, Durham, NC, USA
| | - Dimitrie Siriopol
- Nephrology Clinic, Dialysis and Renal Transplant Center, 'C.I. PARHON' University Hospital, 'Grigore T. Popa' University of Medicine, Iasi, Romania
| | | | - Alberto Ortiz
- School of Medicine, Dialysis Unit, IIS-Fundacion Jimenez Diaz, Universidad Autónoma de Madrid, Madrid, Spain
| | - Mehmet Kanbay
- Department of Medicine, Division of Nephrology, Koc University School of Medicine, Istanbul, Turkey
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7
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Tziastoudi M, Tsezou A, Stefanidis I. Cadherin and Wnt signaling pathways as key regulators in diabetic nephropathy. PLoS One 2021; 16:e0255728. [PMID: 34411124 PMCID: PMC8375992 DOI: 10.1371/journal.pone.0255728] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2020] [Accepted: 07/22/2021] [Indexed: 12/14/2022] Open
Abstract
AIM A recent meta-analysis of genome-wide linkage studies (GWLS) has identified multiple genetic regions suggestive of linkage with DN harboring hundreds of genes. Moving this number of genetic loci forward into biological insight is truly the next step. Here, we approach this challenge with a gene ontology (GO) analysis in order to yield biological and functional role to the genes, an over-representation test to find which GO terms are enriched in the gene list, pathway analysis, as well as protein network analysis. METHOD GO analysis was performed using protein analysis through evolutionary relationships (PANTHER) version 14.0 software and P-values less than 0.05 were considered statistically significant. GO analysis was followed by over-representation test for the identification of enriched terms. Statistical significance was calculated by Fisher's exact test and adjusted using the false discovery rate (FDR) for correction of multiple tests. Cytoscape with the relevant plugins was used for the construction of the protein network and clustering analysis. RESULTS The GO analysis assign multiple GO terms to the genes regarding the molecular function, the biological process and the cellular component, protein class and pathway analysis. The findings of the over-representation test highlight the contribution of cell adhesion regarding the biological process, integral components of plasma membrane regarding the cellular component, chemokines and cytokines with regard to protein class, while the pathway analysis emphasizes the contribution of Wnt and cadherin signaling pathways. CONCLUSIONS Our results suggest that a core feature of the pathogenesis of DN may be a disturbance in Wnt and cadherin signaling pathways, whereas the contribution of chemokines and cytokines need to be studied in additional studies.
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Affiliation(s)
- Maria Tziastoudi
- Department of Nephrology, School of Medicine, University of Thessaly, Larissa, Greece
| | - Aspasia Tsezou
- Laboratory of Biology, Faculty of Medicine, School of Health Sciences, University of Thessaly, Larissa, Greece
- Laboratory of Cytogenetics and Molecular Genetics, Faculty of Medicine, School of Health Sciences, University of Thessaly, Larissa, Greece
| | - Ioannis Stefanidis
- Department of Nephrology, School of Medicine, University of Thessaly, Larissa, Greece
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8
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Ghosh I, Singh RK, Mishra M, Kapoor S, Jana SS. Switching between blebbing and lamellipodia depends on the degree of non-muscle myosin II activity. J Cell Sci 2021; 134:jcs.248732. [PMID: 33298514 DOI: 10.1242/jcs.248732] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2020] [Accepted: 11/19/2020] [Indexed: 01/09/2023] Open
Abstract
Cells can adopt both mesenchymal and amoeboid modes of migration through membrane protrusive activities, namely formation of lamellipodia and blebbing. How the molecular players control the transition between lamellipodia and blebs is yet to be explored. Here, we show that addition of the ROCK inhibitor Y27632 or low doses of blebbistatin, an inhibitor of non-muscle myosin II (NMII) ATPase activity and filament partitioning, induces blebbing to lamellipodia conversion (BLC), whereas addition of low doses of ML7, an inhibitor of myosin light chain kinase (MLCK), induces lamellipodia to blebbing conversion (LBC) in human MDA-MB-231 cells. Similarly, siRNA-mediated knockdown of ROCK and MLCK induces BLC and LBC, respectively. Interestingly, both blebs and lamellipodia membrane protrusions are able to maintain the ratio of phosphorylated to unphosphorylated regulatory light chain at cortices when MLCK and ROCK, respectively, are inhibited either pharmacologically or genetically, suggesting that MLCK and ROCK activities are interlinked in BLC and LBC. Such BLCs and LBCs are also inducible in other cell lines, including MCF7 and MCF10A. These studies reveal that the relative activity of ROCK and MLCK, which controls both the ATPase activity and filament-forming property of NMII, is a determining factor in whether a cell exhibits blebbing or lamellipodia.
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Affiliation(s)
- Indranil Ghosh
- School of Biological Sciences, Indian Association for the Cultivation of Science, Kolkata 700032, India
| | - Raman K Singh
- School of Biological Sciences, Indian Association for the Cultivation of Science, Kolkata 700032, India.,Weizmann Institute of Science, Rehovot 7610001, Israel
| | - Manjari Mishra
- Department of Chemistry, Indian Institute of Technology - Bombay, Mumbai 400076, India
| | - Shobhna Kapoor
- Department of Chemistry, Indian Institute of Technology - Bombay, Mumbai 400076, India
| | - Siddhartha S Jana
- School of Biological Sciences, Indian Association for the Cultivation of Science, Kolkata 700032, India
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9
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Safi W, Kraus A, Grampp S, Schödel J, Buchholz B. Macrophage migration inhibitory factor is regulated by HIF-1α and cAMP and promotes renal cyst cell proliferation in a macrophage-independent manner. J Mol Med (Berl) 2020; 98:1547-1559. [PMID: 32885302 PMCID: PMC7591438 DOI: 10.1007/s00109-020-01964-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2020] [Revised: 08/10/2020] [Accepted: 08/12/2020] [Indexed: 12/17/2022]
Abstract
Progressive cyst growth leads to decline of renal function in polycystic kidney disease. Macrophage migration inhibitory factor (MIF) was found to be upregulated in cyst-lining cells in a mouse model of polycystic kidney disease and to promote cyst growth. In addition, MIF can be secreted by tubular cells and may contribute to cyst growth in an autocrine manner. However, the underlying mechanisms leading to induction of MIF in cyst-lining cells remained elusive. Here, we demonstrate that hypoxia-inducible transcription factor (HIF) 1α upregulates MIF in cyst-lining cells in a tubule-specific PKD1 knockout mouse. Pharmacological stabilization of HIF-1α resulted in significant increase of MIF in cyst epithelial cells whereas tubule-specific knockout of HIF-1α prevented MIF upregulation. Identical regulation could be found for ABCA1, which has been shown to act as a transport protein for MIF. Furthermore, we show that MIF and ABCA1 are direct target genes of HIF-1α in human primary tubular cells. Next to HIF-1α and hypoxia, we found MIF being additionally regulated by cAMP which is a strong promotor of cyst growth. In line with these findings, HIF-1α- and cAMP-dependent in vitro cyst growth could be decreased by the MIF-inhibitor ISO-1 which resulted in reduced cyst cell proliferation. In conclusion, HIF-1α and cAMP regulate MIF in primary tubular cells and cyst-lining epithelial cells, and MIF promotes cyst growth in the absence of macrophages. In line with these findings, the MIF inhibitor ISO-1 attenuates HIF-1α- and cAMP-dependent in vitro cyst enlargement. KEY MESSAGES: • MIF is upregulated in cyst-lining cells in a polycystic kidney disease mouse model. • MIF upregulation is mediated by hypoxia-inducible transcription factor (HIF) 1α. • ABCA1, transport protein for MIF, is also regulated by HIF-1α in vitro and in vivo. • MIF is additionally regulated by cAMP, a strong promotor of cyst growth. • MIF-inhibitor ISO-1 reduces HIF-1α- and cAMP-dependent cyst growth.
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Affiliation(s)
- Wajima Safi
- Department of Nephrology and Hypertension, Friedrich-Alexander-University Erlangen-Nuernberg, Ulmenweg 18, D - 91054, Erlangen, Germany
- Pluripotency for Organ Regeneration, Institute for Bioengineering of Catalonia (IBEC), The Barcelona Institute of Technology (BIST), Barcelona, Spain
| | - Andre Kraus
- Department of Nephrology and Hypertension, Friedrich-Alexander-University Erlangen-Nuernberg, Ulmenweg 18, D - 91054, Erlangen, Germany
| | - Steffen Grampp
- Department of Nephrology and Hypertension, Friedrich-Alexander-University Erlangen-Nuernberg, Ulmenweg 18, D - 91054, Erlangen, Germany
| | - Johannes Schödel
- Department of Nephrology and Hypertension, Friedrich-Alexander-University Erlangen-Nuernberg, Ulmenweg 18, D - 91054, Erlangen, Germany
| | - Bjoern Buchholz
- Department of Nephrology and Hypertension, Friedrich-Alexander-University Erlangen-Nuernberg, Ulmenweg 18, D - 91054, Erlangen, Germany.
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10
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Lauer V, Grampp S, Platt J, Lafleur V, Lombardi O, Choudhry H, Kranz F, Hartmann A, Wullich B, Yamamoto A, Coleman ML, Ratcliffe PJ, Mole DR, Schödel J. Hypoxia drives glucose transporter 3 expression through hypoxia-inducible transcription factor (HIF)-mediated induction of the long noncoding RNA NICI. J Biol Chem 2020; 295:4065-4078. [PMID: 31690629 PMCID: PMC7105321 DOI: 10.1074/jbc.ra119.009827] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2019] [Revised: 10/18/2019] [Indexed: 12/12/2022] Open
Abstract
Hypoxia-inducible transcription factors (HIFs) directly dictate the expression of multiple RNA species including novel and as yet uncharacterized long noncoding transcripts with unknown function. We used pan-genomic HIF-binding and transcriptomic data to identify a novel long noncoding RNA Noncoding Intergenic Co-Induced transcript (NICI) on chromosome 12p13.31 which is regulated by hypoxia via HIF-1 promoter-binding in multiple cell types. CRISPR/Cas9-mediated deletion of the hypoxia-response element revealed co-regulation of NICI and the neighboring protein-coding gene, solute carrier family 2 member 3 (SLC2A3) which encodes the high-affinity glucose transporter 3 (GLUT3). Knockdown or knockout of NICI attenuated hypoxic induction of SLC2A3, indicating a direct regulatory role of NICI in SLC2A3 expression, which was further evidenced by CRISPR/Cas9-VPR-mediated activation of NICI expression. We also demonstrate that regulation of SLC2A3 is mediated through transcriptional activation rather than posttranscriptional mechanisms because knockout of NICI leads to reduced recruitment of RNA polymerase 2 to the SLC2A3 promoter. Consistent with this we observe NICI-dependent regulation of glucose consumption and cell proliferation. Furthermore, NICI expression is regulated by the von Hippel-Lindau (VHL) tumor suppressor and is highly expressed in clear cell renal cell carcinoma (ccRCC), where SLC2A3 expression is associated with patient prognosis, implying an important role for the HIF/NICI/SLC2A3 axis in this malignancy.
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Affiliation(s)
- Victoria Lauer
- Department of Nephrology and Hypertension, Universitätsklinikum Erlangen and Friedrich-Alexander-Universität Erlangen-Nürnberg, Ulmenweg 18, 91054 Erlangen, Germany
| | - Steffen Grampp
- Department of Nephrology and Hypertension, Universitätsklinikum Erlangen and Friedrich-Alexander-Universität Erlangen-Nürnberg, Ulmenweg 18, 91054 Erlangen, Germany
| | - James Platt
- NDM Research Building, University of Oxford, Old Road Campus, Headington, Oxford OX3 7FZ, United Kingdom
| | - Veronique Lafleur
- NDM Research Building, University of Oxford, Old Road Campus, Headington, Oxford OX3 7FZ, United Kingdom
| | - Olivia Lombardi
- NDM Research Building, University of Oxford, Old Road Campus, Headington, Oxford OX3 7FZ, United Kingdom
| | - Hani Choudhry
- Department of Biochemistry, Faculty of Science, Center of Innovation in Personalized Medicine, King Fahd Center for Medical Research, King Abdulaziz University, Jeddah, Saudi Arabia
| | - Franziska Kranz
- Department of Nephrology and Hypertension, Universitätsklinikum Erlangen and Friedrich-Alexander-Universität Erlangen-Nürnberg, Ulmenweg 18, 91054 Erlangen, Germany; Department of Computer Science 9, Friedrich-Alexander-Universität Erlangen-Nürnberg, Cauerstraße 11, 91058 Erlangen, Germany
| | - Arndt Hartmann
- Institute of Pathology, Universitätsklinikum Erlangen and Friedrich-Alexander-Universität Erlangen-Nürnberg, Krankenhausstraße 8-10, 91054 Erlangen, Germany
| | - Bernd Wullich
- Department of Urology and Pediatric Urology, Universitätsklinikum Erlangen and Friedrich-Alexander-Universität Erlangen-Nürnberg, Krankenhausstraße 12, 91054 Erlangen, Germany
| | - Atsushi Yamamoto
- NDM Research Building, University of Oxford, Old Road Campus, Headington, Oxford OX3 7FZ, United Kingdom
| | - Mathew L Coleman
- Institute of Cancer and Genomic Sciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, United Kingdom
| | - Peter J Ratcliffe
- NDM Research Building, University of Oxford, Old Road Campus, Headington, Oxford OX3 7FZ, United Kingdom
| | - David R Mole
- NDM Research Building, University of Oxford, Old Road Campus, Headington, Oxford OX3 7FZ, United Kingdom
| | - Johannes Schödel
- Department of Nephrology and Hypertension, Universitätsklinikum Erlangen and Friedrich-Alexander-Universität Erlangen-Nürnberg, Ulmenweg 18, 91054 Erlangen, Germany.
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11
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Schley G, Grampp S, Goppelt-Struebe M. Inhibition of oxygen-sensing prolyl hydroxylases increases lipid accumulation in human primary tubular epithelial cells without inducing ER stress. Cell Tissue Res 2020; 381:125-140. [PMID: 32189058 PMCID: PMC7306052 DOI: 10.1007/s00441-020-03186-w] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2019] [Accepted: 02/03/2020] [Indexed: 12/18/2022]
Abstract
The role of the hypoxia-inducible transcription factor (HIF) pathway in renal lipid metabolism is largely unknown. As HIF stabilizing prolyl hydroxylase (PHD) inhibitors are currently investigated in clinical trials for the treatment of renal anemia, we studied the effects of genetic deletion and pharmacological inhibition of PHDs on renal lipid metabolism in transgenic mice and human primary tubular epithelial cells (hPTEC). Tubular cell-specific deletion of HIF prolyl hydroxylase 2 (Phd2) increased the size of Oil Red-stained lipid droplets in mice. In hPTEC, the PHD inhibitors (PHDi) DMOG and ICA augmented lipid accumulation, which was visualized by Oil Red staining and assessed by microscopy and an infrared imaging system. PHDi-induced lipid accumulation required the exogenous availability of fatty acids and was observed in both proximal and distal hPTEC. PHDi treatment was not associated with structural features of cytotoxicity in contrast to treatment with the immunosuppressant cyclosporine A (CsA). PHDi and CsA differentially upregulated the expression of the lipid droplet-associated genes PLIN2, PLIN4 and HILPDA. Both PHDi and CsA activated AMP-activated protein kinase (AMPK) indicating the initiation of a metabolic stress response. However, only CsA triggered endoplasmic reticulum (ER) stress as determined by the increased mRNA expression of multiple ER stress markers but CsA-induced ER stress was not linked to lipid accumulation. Our data raise the possibility that PHD inhibition may protect tubular cells from toxic free fatty acids by trapping them as triacylglycerides in lipid droplets. This mechanism might contribute to the renoprotective effects of PHDi in experimental kidney diseases.
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Affiliation(s)
- Gunnar Schley
- Department of Nephrology and Hypertension, Friedrich-Alexander University Erlangen-Nürnberg and University Hospital Erlangen, Loschgestrasse 8, 91054, Erlangen, Germany.
| | - Steffen Grampp
- Department of Nephrology and Hypertension, Friedrich-Alexander University Erlangen-Nürnberg and University Hospital Erlangen, Loschgestrasse 8, 91054, Erlangen, Germany
| | - Margarete Goppelt-Struebe
- Department of Nephrology and Hypertension, Friedrich-Alexander University Erlangen-Nürnberg and University Hospital Erlangen, Loschgestrasse 8, 91054, Erlangen, Germany
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12
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Sun CQ, Arnold RS, Hsieh CL, Dorin JR, Lian F, Li Z, Petros JA. Discovery and mechanisms of host defense to oncogenesis: targeting the β-defensin-1 peptide as a natural tumor inhibitor. Cancer Biol Ther 2019; 20:774-786. [PMID: 30900935 PMCID: PMC6605992 DOI: 10.1080/15384047.2018.1564564] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2018] [Revised: 11/27/2018] [Accepted: 12/25/2018] [Indexed: 12/28/2022] Open
Abstract
Human beta-defensin-1 (hBD-1) is one of a number of small cationic host-defense peptides. Besides its well-known broad-spectrum antimicrobial function, hBD-1 has recently been identified as a chromosome 8p tumor-suppressor gene. The role of hBD-1 in modulating the host immune response to oncogenesis, associated with cell signaling and potential therapeutic applications, has become increasingly appreciated over time. In this study, multiple approaches were used to illustrate hBD-1 anti-tumor activities. Results demonstrate that hBD-1 peptide alters human epidermal growth factor receptor 2 (HER2) signal transduction and represses retroviral-mediated transgene expression in cancer cells. Loss of orthologous murine defense-1 (mBD1) in mice enhances nickel sulfate-induced leiomyosarcoma and causes mouse kidney cells to exhibit increased susceptibility to HPV-16 E6/7-induced neoplastic transformation. Furthermore, for the first time, a novel function of the urine-derived hBD-1 peptide was discovered to suppress bladder cancer growth and this may lead to future applications in the treatment of malignancy.
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Affiliation(s)
- Carrie Q. Sun
- Department of Urology and Winship Cancer Institute, Emory University, Atlanta, Georgia
| | - Rebecca S. Arnold
- Department of Urology and Winship Cancer Institute, Emory University, Atlanta, Georgia
| | - Chia-Ling Hsieh
- Department of Molecular Medicine, China Medical University Hospital, Taipei, Taiwan
| | - Julia R. Dorin
- Center for Inflammation Research, University of Edinburgh, Edinburgh, UK
| | - Fei Lian
- Emory University School of Medicine, Emory University, Atlanta, Georgia
| | - Zhenghong Li
- School of Medicine, Central South University, Changsha City, Human Province, P. R. China
| | - John A. Petros
- Department of Urology and Winship Cancer Institute, Emory University, Atlanta, Georgia
- Atlanta Veterans Affairs Medical Center, Atlanta, Georgia
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13
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Oliveira M, Lira R, Freire T, Luna C, Martins M, Almeida A, Carvalho S, Cortez E, Stumbo AC, Thole A, Carvalho L. Bone marrow mononuclear cell transplantation rescues the glomerular filtration barrier and epithelial cellular junctions in a renovascular hypertension model. Exp Physiol 2019; 104:740-754. [DOI: 10.1113/ep087330] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2018] [Accepted: 02/19/2019] [Indexed: 12/13/2022]
Affiliation(s)
- Mariana Oliveira
- Laboratory of Stem Cell ResearchHistology and Embryology DepartmentBiology InstituteState University of Rio de Janeiro, Rio de Janeiro, RJ, Brazil
| | - Rafaelle Lira
- Laboratory of Stem Cell ResearchHistology and Embryology DepartmentBiology InstituteState University of Rio de Janeiro, Rio de Janeiro, RJ, Brazil
| | - Thiago Freire
- Laboratory of Stem Cell ResearchHistology and Embryology DepartmentBiology InstituteState University of Rio de Janeiro, Rio de Janeiro, RJ, Brazil
| | - Camila Luna
- Laboratory of Stem Cell ResearchHistology and Embryology DepartmentBiology InstituteState University of Rio de Janeiro, Rio de Janeiro, RJ, Brazil
| | - Marcela Martins
- Laboratory of Stem Cell ResearchHistology and Embryology DepartmentBiology InstituteState University of Rio de Janeiro, Rio de Janeiro, RJ, Brazil
| | - Aline Almeida
- Laboratory of Stem Cell ResearchHistology and Embryology DepartmentBiology InstituteState University of Rio de Janeiro, Rio de Janeiro, RJ, Brazil
| | - Simone Carvalho
- Laboratory of Stem Cell ResearchHistology and Embryology DepartmentBiology InstituteState University of Rio de Janeiro, Rio de Janeiro, RJ, Brazil
| | - Erika Cortez
- Laboratory of Stem Cell ResearchHistology and Embryology DepartmentBiology InstituteState University of Rio de Janeiro, Rio de Janeiro, RJ, Brazil
| | - Ana Carolina Stumbo
- Laboratory of Stem Cell ResearchHistology and Embryology DepartmentBiology InstituteState University of Rio de Janeiro, Rio de Janeiro, RJ, Brazil
| | - Alessandra Thole
- Laboratory of Stem Cell ResearchHistology and Embryology DepartmentBiology InstituteState University of Rio de Janeiro, Rio de Janeiro, RJ, Brazil
| | - Lais Carvalho
- Laboratory of Stem Cell ResearchHistology and Embryology DepartmentBiology InstituteState University of Rio de Janeiro, Rio de Janeiro, RJ, Brazil
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14
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Lawson JS, Liu HH, Syme HM, Purcell R, Wheeler-Jones CPD, Elliott J. The cat as a naturally occurring model of renal interstitial fibrosis: Characterisation of primary feline proximal tubular epithelial cells and comparative pro-fibrotic effects of TGF-β1. PLoS One 2018; 13:e0202577. [PMID: 30138414 PMCID: PMC6107233 DOI: 10.1371/journal.pone.0202577] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2018] [Accepted: 08/06/2018] [Indexed: 01/08/2023] Open
Abstract
Chronic kidney disease (CKD) is common in both geriatric cats and aging humans, and is pathologically characterised by chronic tubulointerstitial inflammation and fibrosis in both species. Cats with CKD may represent a spontaneously occurring, non-rodent animal model of human disease, however little is known of feline renal cell biology. In other species, TGF-β1 signalling in the proximal tubular epithelium is thought to play a key role in the initiation and progression of renal fibrosis. In this study, we first aimed to isolate and characterise feline proximal tubular epithelial cells (FPTEC), comparing them to human primary renal epithelial cells (HREC) and the human proximal tubular cell line HK-2. Secondly, we aimed to examine and compare the effect of human recombinant TGF-β1 on cell proliferation, pro-apoptotic signalling and genes associated with epithelial-to-mesenchymal transition (EMT) in feline and human renal epithelial cells. FPTEC were successfully isolated from cadaverous feline renal tissue, and demonstrated a marker protein expression profile identical to that of HREC and HK-2. Exposure to TGF-β1 (0-10 ng/ml) induced a concentration-dependent loss of epithelial morphology and alterations in gene expression consistent with the occurrence of partial EMT in all cell types. This was associated with transcription of downstream pro-fibrotic mediators, growth arrest in FPTEC and HREC (but not HK-2), and increased apoptotic signalling at high concentrations of TGF- β1. These effects were inhibited by the ALK5 (TGF-β1RI) antagonist SB431542 (5 μM), suggesting they are mediated via the ALK5/TGF-β1RII receptor complex. Taken together, these results suggest that TGF-β1 may be involved in epithelial cell dedifferentiation, growth arrest and apoptosis in feline CKD as in human disease, and that cats may be a useful, naturally occurring model of human CKD.
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Affiliation(s)
- Jack S. Lawson
- Comparative Biomedical Sciences, The Royal Veterinary College, London, United Kingdom
- * E-mail:
| | - Hui-Hsuan Liu
- Comparative Biomedical Sciences, The Royal Veterinary College, London, United Kingdom
| | - Harriet M. Syme
- Clinical Sciences and Services, The Royal Veterinary College, North Mymms, Hatfield, Herts, United Kingdom
| | - Robert Purcell
- Comparative Biomedical Sciences, The Royal Veterinary College, London, United Kingdom
| | | | - Jonathan Elliott
- Comparative Biomedical Sciences, The Royal Veterinary College, London, United Kingdom
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15
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Receptor-independent modulation of TGF-β-induced pro-fibrotic pathways by relaxin-2 in human primary tubular epithelial cells. Cell Tissue Res 2018; 374:619-627. [PMID: 30078103 DOI: 10.1007/s00441-018-2904-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2018] [Accepted: 07/24/2018] [Indexed: 10/28/2022]
Abstract
Renal tubular epithelial cells actively contribute to the development of renal fibrosis and may be targeted by anti-fibrotic drugs. Relaxin-2 (RLX2) applied as recombinant protein is suggested to be renoprotective. Therefore, we investigated whether human primary tubular epithelial cells (hPTEC) obtained from various donors were target cells for the anti-fibrotic actions of RLX2. Treatment of hPTEC with RLX2 reduced the TGF-β1-induced secretion of the pro-fibrotic factor CTGF (connective tissue growth factor) and inhibited fibronectin synthesis and secretion. Furthermore, metalloproteinase MMP2 secretion was increased, with no effect on MMP9. Considerable differences were observed between hPTEC obtained from different donors. Therefore, expression of the relaxin family peptide receptor RXFP1, the major mediator of renal RLX2 effects, was analyzed. A validated antibody detected a double band of 80-90 kDa in cellular homogenates by Western blotting. Expression of the detected protein was not altered by incubation with TGF-β1 and RLX2-induced modulation of CTGF expression did not correlate with the putative receptor expression. Therefore, relaxin family receptors RXFP1-4 were assessed by RNA-seq analysis. No evidence was found for mRNA expression of any of these receptors in several hPTEC preparations. Lack of RXFP1 mRNA was confirmed by qPCR using mRNA obtained from THP-1 cells as positive control. Our data thus provide evidence for primary renal human tubular epithelial cells as targets for the anti-fibrotic actions of RLX2. However, anti-fibrotic effects were observed at micromolar concentrations of RLX2 and shown to be independent of RXFP1 expression.
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16
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HIF stabilization inhibits renal epithelial cell migration and is associated with cytoskeletal alterations. Sci Rep 2018; 8:9497. [PMID: 29934555 PMCID: PMC6015081 DOI: 10.1038/s41598-018-27918-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2018] [Accepted: 06/13/2018] [Indexed: 11/23/2022] Open
Abstract
Acute kidney injury (AKI) is a common and potentially lethal complication in the hospitalized patients, with hypoxic injury being as a major cause. The loss of renal tubular epithelial cells (TEC), one of the AKI hallmarks, is potentially followed by tubular regeneration process orchestrated by the remaining uninjured TECs that undergo proliferation and migration. In this study, we used human primary TEC to investigate the initiation of tubular cell migration and associated cytoskeletal alterations in response to pharmacological HIF stabilization which resembles the pathophysiology of hypoxia. Tubular cells have been shown to migrate as cohorts in a wound healing assay. Importantly, cells of distal tubular origin moved faster than those of proximal origin. HIF stabilization impaired TEC migration, which was confirmed by live single cell tracking. HIF stabilization significantly reduced tubular cell migration velocity and promoted cell spreading. In contrast to the control conditions, HIF stabilization induced actin filaments rearrangement and cell adhesion molecules including paxillin and focal adhesion kinase. Condensed bundling of keratin fibers was also observed, while the expression of different types of keratins, phosphorylation of keratin 18, and the microtubule structure were not altered. In summary, HIF stabilization reduced the ability of renal tubular cells to migrate and led to cytoskeleton reorganization. Our data suggested an important involvement of HIF stabilization during the epithelial migration underlying the mechanism of renal regeneration in response to AKI.
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17
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Bombelli S, Meregalli C, Scalia C, Bovo G, Torsello B, De Marco S, Cadamuro M, Viganò P, Strada G, Cattoretti G, Bianchi C, Perego RA. Nephrosphere-Derived Cells Are Induced to Multilineage Differentiation when Cultured on Human Decellularized Kidney Scaffolds. THE AMERICAN JOURNAL OF PATHOLOGY 2017; 188:184-195. [PMID: 29037855 DOI: 10.1016/j.ajpath.2017.09.012] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/21/2017] [Revised: 09/14/2017] [Accepted: 09/18/2017] [Indexed: 02/06/2023]
Abstract
In end-stage chronic kidney disease, the option of organ transplantation is limited because of the scarce availability of kidneys. The combination of stem cell research, regenerative medicine, and tissue engineering seems a promising approach to produce new transplantable kidneys. Currently, the possibility to repopulate naturally obtained scaffolds with cells of different sources is advancing. Our aim was to test, for the first time, whether the nephrosphere (NS) cells, composed by renal stem/progenitor-like cells, were able to repopulate different nephron portions of renal extracellular matrix scaffolds obtained after decellularization of human renal tissue slices. Our decellularization protocol enabled us to obtain a completely acellular renal scaffold while maintaining the extracellular matrix structure and composition in terms of collagen IV, laminin, and fibronectin. NS cells, cultured on decellularized renal scaffolds with basal medium, differentiated into proximal and distal tubules as well as endothelium, as highlighted by histology and by the specific expression of epithelial cytokeratin 8.18, proximal tubular CD10, distal tubular cytokeratin 7, and endothelial von Willebrand factor markers. Endothelial medium promoted the differentiation toward the endothelium, whereas epithelial medium promoted the differentiation toward the epithelium. NS cells seem to be a good tool for scaffold repopulation, paving the way for experimental investigations focused on whole-kidney reconstruction.
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Affiliation(s)
- Silvia Bombelli
- School of Medicine and Surgery, Milano-Bicocca University, Monza, Italy
| | - Chiara Meregalli
- School of Medicine and Surgery, Milano-Bicocca University, Monza, Italy
| | - Carla Scalia
- School of Medicine and Surgery, Milano-Bicocca University, Monza, Italy
| | - Giorgio Bovo
- Urology Unit, Bassini Hospital, Cinisello Balsamo, Italy
| | - Barbara Torsello
- School of Medicine and Surgery, Milano-Bicocca University, Monza, Italy
| | - Sofia De Marco
- School of Medicine and Surgery, Milano-Bicocca University, Monza, Italy
| | | | - Paolo Viganò
- Urology Unit, Bassini Hospital, Cinisello Balsamo, Italy
| | - Guido Strada
- Urology Unit, Bassini Hospital, Cinisello Balsamo, Italy
| | - Giorgio Cattoretti
- School of Medicine and Surgery, Milano-Bicocca University, Monza, Italy; Anatomo-Pathology Unit, San Gerardo Hospital, Monza, Italy
| | - Cristina Bianchi
- School of Medicine and Surgery, Milano-Bicocca University, Monza, Italy
| | - Roberto A Perego
- School of Medicine and Surgery, Milano-Bicocca University, Monza, Italy.
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18
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Grampp S, Schmid V, Salama R, Lauer V, Kranz F, Platt JL, Smythies J, Choudhry H, Goppelt-Struebe M, Ratcliffe PJ, Mole DR, Schödel J. Multiple renal cancer susceptibility polymorphisms modulate the HIF pathway. PLoS Genet 2017; 13:e1006872. [PMID: 28715484 PMCID: PMC5536434 DOI: 10.1371/journal.pgen.1006872] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2017] [Revised: 07/31/2017] [Accepted: 06/15/2017] [Indexed: 12/03/2022] Open
Abstract
Un-physiological activation of hypoxia inducible factor (HIF) is an early event in most renal cell cancers (RCC) following inactivation of the von Hippel-Lindau tumor suppressor. Despite intense study, how this impinges on cancer development is incompletely understood. To test for the impact of genetic signals on this pathway, we aligned human RCC-susceptibility polymorphisms with genome-wide assays of HIF-binding and observed highly significant overlap. Allele-specific assays of HIF binding, chromatin conformation and gene expression together with eQTL analyses in human tumors were applied to mechanistic analysis of one such overlapping site at chromosome 12p12.1. This defined a novel stage-specific mechanism in which the risk polymorphism, rs12814794, directly creates a new HIF-binding site that mediates HIF-1α isoform specific upregulation of its target BHLHE41. The alignment of multiple sites in the HIF cis-acting apparatus with RCC-susceptibility polymorphisms strongly supports a causal model in which minor variation in this pathway exerts significant effects on RCC development.
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MESH Headings
- Alleles
- Basic Helix-Loop-Helix Transcription Factors/genetics
- Basic Helix-Loop-Helix Transcription Factors/metabolism
- Carcinoma, Renal Cell/diagnosis
- Carcinoma, Renal Cell/genetics
- Cell Line, Tumor
- Chromatin Immunoprecipitation
- Chromosomes, Human, Pair 12/genetics
- Cyclin D1
- Gene Expression Regulation, Neoplastic
- Genetic Predisposition to Disease
- Genome-Wide Association Study
- HeLa Cells
- Hep G2 Cells
- High-Throughput Nucleotide Sequencing
- Humans
- Hypoxia-Inducible Factor 1, alpha Subunit/genetics
- Hypoxia-Inducible Factor 1, alpha Subunit/metabolism
- MCF-7 Cells
- Polymorphism, Single Nucleotide
- Quantitative Trait Loci
- RNA, Small Interfering/genetics
- RNA, Small Interfering/metabolism
- Up-Regulation
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Affiliation(s)
- Steffen Grampp
- Department of Nephrology and Hypertension, Universitätsklinikum Erlangen und Friedrich-Alexander-University Erlangen-Nürnberg, Erlangen, Germany
| | - Virginia Schmid
- NDM Research Building, University of Oxford, Old Road Campus, Headington, Oxford, United Kingdom
| | - Rafik Salama
- NDM Research Building, University of Oxford, Old Road Campus, Headington, Oxford, United Kingdom
| | - Victoria Lauer
- Department of Nephrology and Hypertension, Universitätsklinikum Erlangen und Friedrich-Alexander-University Erlangen-Nürnberg, Erlangen, Germany
| | - Franziska Kranz
- Department of Nephrology and Hypertension, Universitätsklinikum Erlangen und Friedrich-Alexander-University Erlangen-Nürnberg, Erlangen, Germany
- Department of Computer Science 9, Friedrich-Alexander-Universität (FAU) Erlangen-Nürnberg, Erlangen, Germany
| | - James L. Platt
- NDM Research Building, University of Oxford, Old Road Campus, Headington, Oxford, United Kingdom
| | - James Smythies
- NDM Research Building, University of Oxford, Old Road Campus, Headington, Oxford, United Kingdom
| | - Hani Choudhry
- Department of Biochemistry, Faculty of Science, Center of Innovation in Personalized Medicine, King Fahd Center for Medical Research, King Abdulaziz University, Jeddah, Saudi Arabia
| | - Margarete Goppelt-Struebe
- Department of Nephrology and Hypertension, Universitätsklinikum Erlangen und Friedrich-Alexander-University Erlangen-Nürnberg, Erlangen, Germany
| | - Peter J. Ratcliffe
- NDM Research Building, University of Oxford, Old Road Campus, Headington, Oxford, United Kingdom
| | - David R. Mole
- NDM Research Building, University of Oxford, Old Road Campus, Headington, Oxford, United Kingdom
| | - Johannes Schödel
- Department of Nephrology and Hypertension, Universitätsklinikum Erlangen und Friedrich-Alexander-University Erlangen-Nürnberg, Erlangen, Germany
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19
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Wanner N, Bechtel-Walz W. Epigenetics of kidney disease. Cell Tissue Res 2017; 369:75-92. [PMID: 28286899 DOI: 10.1007/s00441-017-2588-x] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2016] [Accepted: 02/15/2017] [Indexed: 02/06/2023]
Abstract
DNA methylation and histone modifications determine renal programming and the development and progression of renal disease. The identification of the way in which the renal cell epigenome is altered by environmental modifiers driving the onset and progression of renal diseases has extended our understanding of the pathophysiology of kidney disease progression. In this review, we focus on current knowledge concerning the implications of epigenetic modifications during renal disease from early development to chronic kidney disease progression including renal fibrosis, diabetic nephropathy and the translational potential of identifying new biomarkers and treatments for the prevention and therapy of chronic kidney disease and end-stage kidney disease.
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Affiliation(s)
- Nicola Wanner
- Department of Medicine IV, Faculty of Medicine, University of Freiburg, Freiburg, Germany. .,Center for Systems Biology (ZBSA), Albert-Ludwigs-University, Freiburg, Germany. .,Renal Division, University Hospital Freiburg, Breisacher Strasse 66, 79106, Freiburg, Germany.
| | - Wibke Bechtel-Walz
- Department of Medicine IV, Faculty of Medicine, University of Freiburg, Freiburg, Germany. .,Renal Division, University Hospital Freiburg, Breisacher Strasse 66, 79106, Freiburg, Germany.
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20
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Muehlich S, Rehm M, Ebenau A, Goppelt-Struebe M. Synergistic induction of CTGF by cytochalasin D and TGFβ-1 in primary human renal epithelial cells: Role of transcriptional regulators MKL1, YAP/TAZ and Smad2/3. Cell Signal 2016; 29:31-40. [PMID: 27721022 DOI: 10.1016/j.cellsig.2016.10.002] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2016] [Revised: 09/26/2016] [Accepted: 10/06/2016] [Indexed: 02/08/2023]
Abstract
Changes in cell morphology that involve alterations of the actin cytoskeleton are a hallmark of diseased renal tubular epithelial cells. While the impact of actin remodeling on gene expression has been analyzed in many model systems based on cell lines, this study investigated human primary tubular epithelial cells isolated from healthy parts of tumor nephrectomies. Latrunculin B (LatB) and cytochalasin D (CytoD) were used to modulate G-actin levels in a receptor-independent manner. Both compounds (at 0.5μM) profoundly altered F-actin structures in a Rho kinase-dependent manner, but only CytoD strongly induced the pro-fibrotic factor CTGF (connective tissue growth factor). CTGF induction was dependent on YAP as shown by transient downregulation experiments. However, CytoD did not alter the nuclear localization of either YAP or TAZ, whereas LatB reduced nuclear levels particularly of TAZ. CytoD modified MKL1, a coactivator of serum response factor (SRF) regulating CTGF induction, and promoted its nuclear localization. TGFβ-1 is one of the major factors involved in tubulointerstitial disease and an inducer of CTGF. Preincubation with CytoD but not LatB synergistically enhanced the TGFβ-1-stimulated synthesis of CTGF, both in cells cultured on plastic dishes as well as in polarized epithelial cells. CytoD had no direct effect on the phosphorylation of Smad2/3, but facilitated their phosphorylation and thus activation by TGFβ-1. Our present findings provide evidence that morphological alterations have a strong impact on cellular signaling of one of the major pro-fibrotic factors, TGFβ-1. However, our data also indicate that changes in cell morphology per se cannot predict those interactions which are critically dependent on molecular fine tuning of actin reorganization.
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Affiliation(s)
- Susanne Muehlich
- Walther Straub Institute of Pharmacology and Toxicology, Ludwig-Maximilians-University Munich, Goethestrasse 33, D-80336 München, Germany
| | - Margot Rehm
- Department of Nephrology and Hypertension, Friedrich-Alexander-Universität Erlangen-Nürnberg, Loschgestrasse 8, D-91054 Erlangen, Germany
| | - Astrid Ebenau
- Department of Nephrology and Hypertension, Friedrich-Alexander-Universität Erlangen-Nürnberg, Loschgestrasse 8, D-91054 Erlangen, Germany
| | - Margarete Goppelt-Struebe
- Department of Nephrology and Hypertension, Friedrich-Alexander-Universität Erlangen-Nürnberg, Loschgestrasse 8, D-91054 Erlangen, Germany.
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21
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P2Y2R is a direct target of HIF-1α and mediates secretion-dependent cyst growth of renal cyst-forming epithelial cells. Purinergic Signal 2016; 12:687-695. [PMID: 27565965 DOI: 10.1007/s11302-016-9532-5] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2016] [Accepted: 08/18/2016] [Indexed: 01/01/2023] Open
Abstract
Polycystic kidney diseases are characterized by numerous renal cysts that continuously enlarge resulting in compression of intact nephrons and tissue hypoxia. Recently, we have shown that hypoxia-inducible factor (HIF)-1α promotes secretion-dependent cyst expansion, presumably by transcriptional regulation of proteins that are involved in calcium-activated chloride secretion. Here, we report that HIF-1α directly activates expression of the purinergic receptor P2Y2R in human primary renal tubular cells. In addition, we found that P2Y2R is highly expressed in cyst-lining cells of human ADPKD kidneys as well as PKD1 orthologous mouse kidneys. Knockdown of P2Y2R in renal collecting duct cells inhibited calcium-dependent chloride secretion in Ussing chamber analyses. In line with these findings, knockdown of P2Y2R retarded cyst expansion in vitro and prevented ATP- and HIF-1α-dependent cyst growth. In conclusion, P2Y2R mediates ATP-dependent cyst growth and is transcriptionally regulated by HIF-1α. These findings provide further mechanistic evidence on how hypoxia promotes cyst growth.
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Montford JR, Lehman AMB, Scobey MS, Weiser-Evans MCM, Nemenoff RA, Furgeson SB. Cytosolic phospholipase A 2α increases proliferation and de-differentiation of human renal tubular epithelial cells. Prostaglandins Other Lipid Mediat 2016; 126:1-8. [PMID: 27554058 DOI: 10.1016/j.prostaglandins.2016.08.001] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2016] [Revised: 07/14/2016] [Accepted: 08/19/2016] [Indexed: 01/03/2023]
Abstract
The group IVA calcium-dependent cytosolic phospholipase A2 (cPLA2α) enzyme controls the release of arachidonic acid from membrane bound phospholipids and is the rate-limiting step in production of eicosanoids. A variety of different kidney injuries activate cPLA2α, therefore we hypothesized that cPLA2α activity would regulate pathologic processes in HK-2 cells, a human renal tubular epithelial cell line, by regulating cell phenotype and proliferation. In two lentiviral cPLA2α-silenced knockdowns, we observed decreased proliferation and increased apoptosis compared to control HK-2 cells. cPLA2α-silenced cells also demonstrated an altered morphology, had increased expression E-cadherin, and decreased expression of Ncadherin. Increased levels of E-cadherin were associated with increased promoter activity and decreased levels of SNAIL1, SNAIL2, and ZEB1, transcriptional repressors of E-cadherin expression. Addition of exogenous arachidonic acid, but not PGE2, reversed the phenotypic changes in cPLA2α-silenced cells. These data suggest that cPLA2α may play a key role in renal repair after injury through a PGE2-independent mechanism.
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Affiliation(s)
- John R Montford
- Division of Renal Diseases and Hypertension, Department of Medicine, University of Colorado-Anschutz Medical Campus, Aurora, CO, United States.
| | - Allison M B Lehman
- Division of Renal Diseases and Hypertension, Department of Medicine, University of Colorado-Anschutz Medical Campus, Aurora, CO, United States
| | - Micah S Scobey
- Division of Renal Diseases and Hypertension, Department of Medicine, University of Colorado-Anschutz Medical Campus, Aurora, CO, United States
| | - Mary C M Weiser-Evans
- Division of Renal Diseases and Hypertension, Department of Medicine, University of Colorado-Anschutz Medical Campus, Aurora, CO, United States
| | - Raphael A Nemenoff
- Division of Renal Diseases and Hypertension, Department of Medicine, University of Colorado-Anschutz Medical Campus, Aurora, CO, United States
| | - Seth B Furgeson
- Division of Renal Diseases and Hypertension, Department of Medicine, University of Colorado-Anschutz Medical Campus, Aurora, CO, United States; Denver Health and Hospitals, Denver, CO, United States
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23
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Preisser F, Giehl K, Rehm M, Goppelt-Struebe M. Inhibitors of oxygen sensing prolyl hydroxylases regulate nuclear localization of the transcription factors Smad2 and YAP/TAZ involved in CTGF synthesis. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2016; 1863:2027-36. [DOI: 10.1016/j.bbamcr.2016.05.001] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/07/2016] [Revised: 04/25/2016] [Accepted: 05/03/2016] [Indexed: 11/27/2022]
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Major Action of Endogenous Lysyl Oxidase in Clear Cell Renal Cell Carcinoma Progression and Collagen Stiffness Revealed by Primary Cell Cultures. THE AMERICAN JOURNAL OF PATHOLOGY 2016; 186:2473-85. [PMID: 27449199 DOI: 10.1016/j.ajpath.2016.05.019] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/20/2015] [Revised: 04/27/2016] [Accepted: 05/23/2016] [Indexed: 11/20/2022]
Abstract
Human clear cell renal cell carcinoma (ccRCC) is therapy resistant; therefore, it is worthwhile studying in depth the molecular aspects of its progression. In ccRCC the biallelic inactivation of the VHL gene leads to stabilization of hypoxia-inducible factors (HIFs). Among the targets of HIF-1α transcriptional activity is the LOX gene, which codes for the inactive proenzyme (Pro-Lox) from which, after extracellular secretion and proteolysis, derives the active enzyme (Lox) and the propeptide (Lox-PP). By increasing stiffness of extracellular matrix by collagen crosslinking, Lox promotes tumor progression and metastasis. Lox and Lox-PP can reenter the cells where Lox promotes cell proliferation and invasion, whereas Lox-PP acts as tumor suppressor because of its Ras recision and apoptotic activity. Few data are available concerning LOX in ccRCC. Using an in vitro model of ccRCC primary cell cultures, we performed, for the first time in ccRCC, a detailed study of endogenous LOX and also investigated their transcriptomic profile. We found that endogenous LOX is overexpressed in ccRCC, is involved in a positive-regulative loop with HIF-1α, and has a major action on ccRCC progression through cellular adhesion, migration, and collagen matrix stiffness increment; however, the oncosuppressive action of Lox-PP was not found to prevail. These findings may suggest translational approaches for new therapeutic strategies in ccRCC.
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25
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Torsello B, Bianchi C, Meregalli C, Di Stefano V, Invernizzi L, De Marco S, Bovo G, Brivio R, Strada G, Bombelli S, Perego RA. Arg tyrosine kinase modulates TGF-β1 production in human renal tubular cells under high-glucose conditions. J Cell Sci 2016; 129:2925-36. [PMID: 27298228 DOI: 10.1242/jcs.183640] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2015] [Accepted: 04/23/2016] [Indexed: 01/15/2023] Open
Abstract
Renal tubular cells are involved in the tubular interstitial fibrosis observed in diabetic nephropathy. It is debated whether epithelial-mesenchymal transition (EMT) affects tubular cells, which under high-glucose conditions overproduce transforming growth factor-β (TGF-β), a fibrogenic cytokine involved in interstitial fibrosis development. Our study investigated the involvement of non-receptor tyrosine kinase Arg (also called Abl2) in TGF-β production. Human primary tubular cell cultures exposed to high-glucose conditions were used. These cells showed an elongated morphology, stress fibers and vimentin increment but maintained most of the epithelial marker expression and distribution. In these cells exposed to high glucose, which overexpressed and secreted active TGF-β1, Arg protein and activity was downregulated. A further TGF-β1 increase was induced by Arg silencing with siRNA, as with the Arg tyrosine kinase inhibitor Imatinib. In the cells exposed to high glucose, reactive oxygen species (ROS)-dependent Arg kinase downregulation induced both RhoA activation, through p190RhoGAPA (also known as ARHGAP35) modulation, and proteasome activity inhibition. These data evidence a new specific involvement of Arg kinase into the regulation of TGF-β1 expression in tubular cells under high-glucose conditions and provide cues for new translational approaches in diabetic nephropathy.
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Affiliation(s)
- Barbara Torsello
- School of Medicine and Surgery, Milano-Bicocca University, Monza 20900, Italy
| | - Cristina Bianchi
- School of Medicine and Surgery, Milano-Bicocca University, Monza 20900, Italy
| | - Chiara Meregalli
- School of Medicine and Surgery, Milano-Bicocca University, Monza 20900, Italy
| | - Vitalba Di Stefano
- School of Medicine and Surgery, Milano-Bicocca University, Monza 20900, Italy
| | - Lara Invernizzi
- School of Medicine and Surgery, Milano-Bicocca University, Monza 20900, Italy
| | - Sofia De Marco
- School of Medicine and Surgery, Milano-Bicocca University, Monza 20900, Italy
| | - Giorgio Bovo
- Anatomo-Pathology Unit, San Gerardo Hospital, Monza 20900, Italy
| | - Rinaldo Brivio
- Clinical Pathology Unit, San Gerardo Hospital, Monza 20900, Italy
| | - Guido Strada
- Urology Unit, Bassini ICP Hospital, Milano 20092, Italy
| | - Silvia Bombelli
- School of Medicine and Surgery, Milano-Bicocca University, Monza 20900, Italy
| | - Roberto A Perego
- School of Medicine and Surgery, Milano-Bicocca University, Monza 20900, Italy
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26
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Cicha I, Scheffler L, Ebenau A, Lyer S, Alexiou C, Goppelt-Struebe M. Mitoxantrone-loaded superparamagnetic iron oxide nanoparticles as drug carriers for cancer therapy: Uptake and toxicity in primary human tubular epithelial cells. Nanotoxicology 2015; 10:557-66. [DOI: 10.3109/17435390.2015.1095364] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
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27
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Forschbach V, Goppelt-Struebe M, Kunzelmann K, Schreiber R, Piedagnel R, Kraus A, Eckardt KU, Buchholz B. Anoctamin 6 is localized in the primary cilium of renal tubular cells and is involved in apoptosis-dependent cyst lumen formation. Cell Death Dis 2015; 6:e1899. [PMID: 26448322 PMCID: PMC4632301 DOI: 10.1038/cddis.2015.273] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2015] [Revised: 08/11/2015] [Accepted: 08/27/2015] [Indexed: 02/07/2023]
Abstract
Primary cilia are antenna-like structures projected from the apical surface of various mammalian cells including renal tubular cells. Functional or structural defects of the cilium lead to systemic disorders comprising polycystic kidneys as a key feature. Here we show that anoctamin 6 (ANO6), a member of the anoctamin chloride channel family, is localized in the primary cilium of renal epithelial cells in vitro and in vivo. ANO6 was not essential for cilia formation and had no effect on in vitro cyst expansion. However, knockdown of ANO6 impaired cyst lumen formation of MDCK cells in three-dimensional culture. In the absence of ANO6, apoptosis was reduced and epithelial cells were incompletely removed from the center of cell aggregates, which form in the early phase of cystogenesis. In line with these data, we show that ANO6 is highly expressed in apoptotic cyst epithelial cells of human polycystic kidneys. These data identify ANO6 as a cilium-associated protein and suggest its functional relevance in cyst formation.
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Affiliation(s)
- V Forschbach
- Department of Nephrology and Hypertension, Friedrich-Alexander-University Erlangen-Nuernberg, 91054 Erlangen, Germany
| | - M Goppelt-Struebe
- Department of Nephrology and Hypertension, Friedrich-Alexander-University Erlangen-Nuernberg, 91054 Erlangen, Germany
| | - K Kunzelmann
- Department of Physiology, University of Regensburg, 93053 Regensburg, Germany
| | - R Schreiber
- Department of Physiology, University of Regensburg, 93053 Regensburg, Germany
| | - R Piedagnel
- Sorbonne Universités, UPMC Univ Paris 06, UMR_S 1155, F-75005 Paris, France
- INSERM, UMR_S 1155, F-75005 Paris, France
| | - A Kraus
- Department of Nephrology and Hypertension, Friedrich-Alexander-University Erlangen-Nuernberg, 91054 Erlangen, Germany
| | - K-U Eckardt
- Department of Nephrology and Hypertension, Friedrich-Alexander-University Erlangen-Nuernberg, 91054 Erlangen, Germany
| | - B Buchholz
- Department of Nephrology and Hypertension, Friedrich-Alexander-University Erlangen-Nuernberg, 91054 Erlangen, Germany
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28
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Giehl K, Keller C, Muehlich S, Goppelt-Struebe M. Actin-mediated gene expression depends on RhoA and Rac1 signaling in proximal tubular epithelial cells. PLoS One 2015; 10:e0121589. [PMID: 25816094 PMCID: PMC4376694 DOI: 10.1371/journal.pone.0121589] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2014] [Accepted: 02/14/2015] [Indexed: 12/29/2022] Open
Abstract
Morphological alterations of cells can lead to modulation of gene expression. An essential link is the MKL1-dependent activation of serum response factor (SRF), which translates changes in the ratio of G- and F-actin into mRNA transcription. SRF activation is only partially characterized in non-transformed epithelial cells. Therefore, the impact of GTPases of the Rho family and changes in F-actin structures were analyzed in renal proximal tubular epithelial cells. Activation of SRF signaling was compared to the regulation of a known MKL1/SRF target gene, connective tissue growth factor (CTGF). In the human proximal tubular cell line HKC-8 overexpression of two actin mutants either favoring or preventing the formation of F-actin fibers regulated SRF-mediated transcription as well as CTGF expression. Only overexpression of constitutively active RhoA activated SRF-dependent gene expression whereas no effect was detected upon overexpression of Rac1 mutants. To elucidate the functional role of Rho kinases as downstream mediators of RhoA, pharmacological inhibition and genetic inhibition by transient siRNA knock down were compared. Upon stimulation with lysophosphatidic acid (LPA) Rho kinase inhibitors partially suppressed SRF-mediated transcription, whereas interference with Rho kinase expression by siRNA reduced activation of SRF, but barely affected CTGF expression. Together with the partial inhibition of CTGF expression by the pharmacological inhibitors Y27432 and H1154, Rho kinases seem to be less important in mediating RhoA signaling related to CTGF expression in HKC-8 epithelial cells. Short term pharmacological inhibition of Rac1 activity by EHT1864 reduced SRF-dependent CTGF expression in HKC-8 cells, but was overcome by a stimulatory effect after prolonged incubation after 4-6 h. Similarly, human primary cells of proximal but not of distal tubular origin showed inhibitory as well as stimulatory effects of Rac1 inhibition. Thus, RhoA signaling activates MKL1-SRF-mediated CTGF expression in proximal tubular cells, whereas Rac1 signaling is more complex with adaptive cellular responses.
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Affiliation(s)
- Klaudia Giehl
- Signal Transduction of Cellular Motility, Internal Medicine V, Justus-Liebig-University Giessen, Giessen, Germany
| | - Christof Keller
- Department of Nephrology and Hypertension, Friedrich-Alexander Universität Erlangen-Nürnberg, Erlangen, Germany
| | - Susanne Muehlich
- Walther Straub Institute of Pharmacology and Toxicology, Ludwig-Maximilians-University, Munich, Germany
| | - Margarete Goppelt-Struebe
- Department of Nephrology and Hypertension, Friedrich-Alexander Universität Erlangen-Nürnberg, Erlangen, Germany
- * E-mail:
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29
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ZHU TIECHUI, YANG JUN, LIU XIANGDONG, ZHANG LIANYUN, ZHANG JIE, WANG YONGTAO, MA HAIJUN, REN ZHENHUI. Hypoxia-inducible adrenomedullin ameliorates the epithelial-to-mesenchymal transition in human proximal tubular epithelial cells. Mol Med Rep 2015; 11:3760-6. [DOI: 10.3892/mmr.2015.3189] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2014] [Accepted: 08/19/2014] [Indexed: 11/06/2022] Open
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30
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McClelland A, Hagiwara S, Kantharidis P. Where are we in diabetic nephropathy. Curr Opin Nephrol Hypertens 2014; 23:80-6. [DOI: 10.1097/01.mnh.0000437612.50040.ae] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
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31
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PKH(high) cells within clonal human nephrospheres provide a purified adult renal stem cell population. Stem Cell Res 2013; 11:1163-77. [PMID: 24012544 DOI: 10.1016/j.scr.2013.08.004] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/20/2012] [Revised: 08/02/2013] [Accepted: 08/03/2013] [Indexed: 01/09/2023] Open
Abstract
The existence and identification of adult renal stem cells is a controversial issue. In this study, renal stem cells were identified from cultures of clonal human nephrospheres. The cultured nephrospheres exhibited the activation of stem cell pathways and contained cells at different levels of maturation. In each nephrosphere the presence of 1.12-1.25 cells mirroring stem cell properties was calculated. The nephrosphere cells were able to generate three-dimensional tubular structures in 3D cultures and in vivo. In clonal human nephrospheres a PKH(high) phenotype was isolated using PKH26 epifluorescence, which can identify quiescent cells within the nephrospheres. The PKH(high) cells, capable of self-renewal and of generating a differentiated epithelial, endothelial and podocytic progeny, can also survive in vivo maintaining the undifferentiated status. The PKH(high) status, together with a CD133(+)/CD24(-) phenotype, identified a homogeneous cell population displaying in vitro self-renewal and multipotency capacity. The resident adult renal stem cell population isolated from nephrospheres can be used for the study of mechanisms that regulate self-renewal and differentiation in adult renal tissue as well as in renal pathological conditions.
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microRNA-124 inhibits migration and invasion by down-regulating ROCK1 in glioma. PLoS One 2013; 8:e69478. [PMID: 23936026 PMCID: PMC3720724 DOI: 10.1371/journal.pone.0069478] [Citation(s) in RCA: 84] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2013] [Accepted: 06/10/2013] [Indexed: 12/19/2022] Open
Abstract
Background The extraordinary invasive capability is a major cause of treatment failure and tumor recurrence in glioma, however, the molecular and cellular mechanisms governing glioma invasion remain poorly understood. Evidence in other cell systems has implicated the regulatory role of microRNA in cell motility and invasion, which promotes us to investigate the biological functions of miR-124 in glioma in this regard. Results We have found that miR-124 is dramatically downregulated in clinical specimen of glioma and is negatively correlated with the tumor pathological grading in the current study. The cells transfected by miR-124 expression vector have demonstrated retarded cell mobility. Using a bioinformatics analysis approach, rho-associated coiled-coil containing protein kinase 1 (ROCK1), a well-known cell mobility-related gene, has been identified as the target of miR-124. A dual-luciferase reporter assay was used to confirm that miR-124 targeted directly the 3′UTR of ROCK1 gene and repressed the ROCK1 expression in U87MG human glioma cell line. Furthermore, experiments have shown that the decreased cell mobility was due to the actin cytoskeleton rearrangements and the reduced cell surface ruffle in U87MG glioma cells. These results are similar to the cellular responses of U87MG glioma cells to the treatment of Y-27632, an inhibitor of ROCK protein. Moreover, a constitutively active ROCK1 in miR-124 over-expressed glioma cells reversed the effects of miR-124. Our results revealed a novel mechanism that miR-124 inhibits glioma cells migration and invasion via ROCK1 downregulation. Conclusions These results suggest that miR-124 may function as anti-migration and anti-invasion influence in glioma and provides a potential approach for developing miR-124-based therapeutic strategies for malignant glioma therapy.
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