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Proteome-Wide Differential Effects of Peritoneal Dialysis Fluid Properties in an In Vitro Human Endothelial Cell Model. Int J Mol Sci 2022; 23:ijms23148010. [PMID: 35887356 PMCID: PMC9317527 DOI: 10.3390/ijms23148010] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2022] [Revised: 07/13/2022] [Accepted: 07/15/2022] [Indexed: 01/27/2023] Open
Abstract
To replace kidney function, peritoneal dialysis (PD) utilizes hyperosmotic PD fluids with specific physico-chemical properties. Their composition induces progressive damage of the peritoneum, leading to vasculopathies, decline of membrane function, and PD technique failure. Clinically used PD fluids differ in their composition but still remain bioincompatible. We mapped the molecular pathomechanisms in human endothelial cells induced by the different characteristics of widely used PD fluids by proteomics. Of 7894 identified proteins, 3871 were regulated at least by 1 and 49 by all tested PD fluids. The latter subset was enriched for cell junction-associated proteins. The different PD fluids individually perturbed proteins commonly related to cell stress, survival, and immune function pathways. Modeling two major bioincompatibility factors of PD fluids, acidosis, and glucose degradation products (GDPs) revealed distinct effects on endothelial cell function and regulation of cellular stress responses. Proteins and pathways most strongly affected were members of the oxidative stress response. Addition of the antioxidant and cytoprotective additive, alanyl-glutamine (AlaGln), to PD fluids led to upregulation of thioredoxin reductase-1, an antioxidant protein, potentially explaining the cytoprotective effect of AlaGln. In conclusion, we mapped out the molecular response of endothelial cells to PD fluids, and provided new evidence for their specific pathomechanisms, crucial for improvement of PD therapies.
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2
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Herzog R, Sacnun JM, González-Mateo G, Bartosova M, Bialas K, Wagner A, Unterwurzacher M, Sobieszek IJ, Daniel-Fischer L, Rusai K, Pascual-Antón L, Kaczirek K, Vychytil A, Schmitt CP, López-Cabrera M, Alper SL, Aufricht C, Kratochwill K. Lithium preserves peritoneal membrane integrity by suppressing mesothelial cell αB-crystallin. Sci Transl Med 2021; 13:13/608/eaaz9705. [PMID: 34433641 DOI: 10.1126/scitranslmed.aaz9705] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2019] [Revised: 04/30/2021] [Accepted: 08/04/2021] [Indexed: 01/18/2023]
Abstract
Life-saving renal replacement therapy by peritoneal dialysis (PD) is limited in use and duration by progressive impairment of peritoneal membrane integrity and homeostasis. Preservation of peritoneal membrane integrity during chronic PD remains an urgent but long unmet medical need. PD therapy failure results from peritoneal fibrosis and angiogenesis caused by hypertonic PD fluid (PDF)-induced mesothelial cytotoxicity. However, the pathophysiological mechanisms involved are incompletely understood, limiting identification of therapeutic targets. We report that addition of lithium chloride (LiCl) to PDF is a translatable intervention to counteract PDF-induced mesothelial cell death, peritoneal membrane fibrosis, and angiogenesis. LiCl improved mesothelial cell survival in a dose-dependent manner. Combined transcriptomic and proteomic characterization of icodextrin-based PDF-induced mesothelial cell injury identified αB-crystallin as the mesothelial cell protein most consistently counter-regulated by LiCl. In vitro and in vivo overexpression of αB-crystallin triggered a fibrotic phenotype and PDF-like up-regulation of vascular endothelial growth factor (VEGF), CD31-positive cells, and TGF-β-independent activation of TGF-β-regulated targets. In contrast, αB-crystallin knockdown decreased VEGF expression and early mesothelial-to-mesenchymal transition. LiCl reduced VEGF release and counteracted fibrosis- and angiogenesis-associated processes. αB-crystallin in patient-derived mesothelial cells was specifically up-regulated in response to PDF and increased in peritoneal mesothelial cells from biopsies from pediatric patients undergoing PD, correlating with markers of angiogenesis and fibrosis. LiCl-supplemented PDF promoted morphological preservation of mesothelial cells and the submesothelial zone in a mouse model of chronic PD. Thus, repurposing LiCl as a cytoprotective PDF additive may offer a translatable therapeutic strategy to combat peritoneal membrane deterioration during PD therapy.
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Affiliation(s)
- Rebecca Herzog
- Christian Doppler Laboratory for Molecular Stress Research in Peritoneal Dialysis, Department of Pediatrics and Adolescent Medicine, Medical University of Vienna, 1090 Vienna, Austria.,Division of Pediatric Nephrology and Gastroenterology, Department of Pediatrics and Adolescent Medicine, Comprehensive Center for Pediatrics, Medical University of Vienna, 1090 Vienna, Austria
| | - Juan Manuel Sacnun
- Christian Doppler Laboratory for Molecular Stress Research in Peritoneal Dialysis, Department of Pediatrics and Adolescent Medicine, Medical University of Vienna, 1090 Vienna, Austria.,Division of Pediatric Nephrology and Gastroenterology, Department of Pediatrics and Adolescent Medicine, Comprehensive Center for Pediatrics, Medical University of Vienna, 1090 Vienna, Austria.,Zytoprotec GmbH, 1090 Vienna, Austria
| | - Guadalupe González-Mateo
- Tissue and Organ Homeostasis, Molecular Biology Centre Severo Ochoa, CSIC-UAM, 28049 Madrid, Spain
| | - Maria Bartosova
- Division of Pediatric Nephrology, Center for Pediatric and Adolescent Medicine, University of Heidelberg, 69120 Heidelberg, Germany
| | - Katarzyna Bialas
- Christian Doppler Laboratory for Molecular Stress Research in Peritoneal Dialysis, Department of Pediatrics and Adolescent Medicine, Medical University of Vienna, 1090 Vienna, Austria.,Zytoprotec GmbH, 1090 Vienna, Austria
| | - Anja Wagner
- Christian Doppler Laboratory for Molecular Stress Research in Peritoneal Dialysis, Department of Pediatrics and Adolescent Medicine, Medical University of Vienna, 1090 Vienna, Austria.,Division of Pediatric Nephrology and Gastroenterology, Department of Pediatrics and Adolescent Medicine, Comprehensive Center for Pediatrics, Medical University of Vienna, 1090 Vienna, Austria
| | - Markus Unterwurzacher
- Christian Doppler Laboratory for Molecular Stress Research in Peritoneal Dialysis, Department of Pediatrics and Adolescent Medicine, Medical University of Vienna, 1090 Vienna, Austria.,Division of Pediatric Nephrology and Gastroenterology, Department of Pediatrics and Adolescent Medicine, Comprehensive Center for Pediatrics, Medical University of Vienna, 1090 Vienna, Austria
| | - Isabel J Sobieszek
- Christian Doppler Laboratory for Molecular Stress Research in Peritoneal Dialysis, Department of Pediatrics and Adolescent Medicine, Medical University of Vienna, 1090 Vienna, Austria.,Division of Pediatric Nephrology and Gastroenterology, Department of Pediatrics and Adolescent Medicine, Comprehensive Center for Pediatrics, Medical University of Vienna, 1090 Vienna, Austria
| | - Lisa Daniel-Fischer
- Christian Doppler Laboratory for Molecular Stress Research in Peritoneal Dialysis, Department of Pediatrics and Adolescent Medicine, Medical University of Vienna, 1090 Vienna, Austria.,Division of Pediatric Nephrology and Gastroenterology, Department of Pediatrics and Adolescent Medicine, Comprehensive Center for Pediatrics, Medical University of Vienna, 1090 Vienna, Austria
| | - Krisztina Rusai
- Division of Pediatric Nephrology and Gastroenterology, Department of Pediatrics and Adolescent Medicine, Comprehensive Center for Pediatrics, Medical University of Vienna, 1090 Vienna, Austria
| | - Lucía Pascual-Antón
- Tissue and Organ Homeostasis, Molecular Biology Centre Severo Ochoa, CSIC-UAM, 28049 Madrid, Spain
| | - Klaus Kaczirek
- Department of General Surgery, Medical University of Vienna, 1090 Vienna, Austria
| | - Andreas Vychytil
- Department of Medicine III, Division of Nephrology and Dialysis, Medical University of Vienna, 1090 Vienna, Austria
| | - Claus Peter Schmitt
- Division of Pediatric Nephrology, Center for Pediatric and Adolescent Medicine, University of Heidelberg, 69120 Heidelberg, Germany
| | - Manuel López-Cabrera
- Tissue and Organ Homeostasis, Molecular Biology Centre Severo Ochoa, CSIC-UAM, 28049 Madrid, Spain
| | - Seth L Alper
- Division of Nephrology, Beth Israel Deaconess Medical Center, Boston, MA 02215, USA.,Department of Medicine, Harvard Medical School, Boston, MA 02115, USA
| | - Christoph Aufricht
- Division of Pediatric Nephrology and Gastroenterology, Department of Pediatrics and Adolescent Medicine, Comprehensive Center for Pediatrics, Medical University of Vienna, 1090 Vienna, Austria
| | - Klaus Kratochwill
- Christian Doppler Laboratory for Molecular Stress Research in Peritoneal Dialysis, Department of Pediatrics and Adolescent Medicine, Medical University of Vienna, 1090 Vienna, Austria. .,Division of Pediatric Nephrology and Gastroenterology, Department of Pediatrics and Adolescent Medicine, Comprehensive Center for Pediatrics, Medical University of Vienna, 1090 Vienna, Austria
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3
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Masola V, Bonomini M, Onisto M, Ferraro PM, Arduini A, Gambaro G. Biological Effects of XyloCore, a Glucose Sparing PD Solution, on Mesothelial Cells: Focus on Mesothelial-Mesenchymal Transition, Inflammation and Angiogenesis. Nutrients 2021; 13:2282. [PMID: 34209455 PMCID: PMC8308380 DOI: 10.3390/nu13072282] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2021] [Revised: 06/25/2021] [Accepted: 06/29/2021] [Indexed: 12/15/2022] Open
Abstract
Glucose-based solutions remain the most used osmotic agents in peritoneal dialysis (PD), but unavoidably they contribute to the loss of peritoneal filtration capacity. Here, we evaluated at a molecular level the effects of XyloCore, a new PD solution with a low glucose content, in mesothelial and endothelial cells. Cell viability, integrity of mesothelial and endothelial cell membrane, activation of mesothelial and endothelial to mesenchymal transition programs, inflammation, and angiogenesis were evaluated by several techniques. Results showed that XyloCore preserves mesothelial and endothelial cell viability and membrane integrity. Moreover XyloCore, unlike glucose-based solutions, does not exert pro-fibrotic, -inflammatory, and -angiogenic effects. Overall, the in vitro evidence suggests that XyloCore could represent a potential biocompatible solution promising better outcomes in clinical practice.
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Affiliation(s)
- Valentina Masola
- Division of Nephrology and Dialysis, Department of Medicine, Piazzale A. Stefani 1, 37126 Verona, Italy;
- Department of Biomedical Sciences, University of Padova, Viale G. Colombo 3, 35121 Padova, Italy;
| | - Mario Bonomini
- Nephrology and Dialysis Unit, Department of Medicine, G. d’Annunzio University, Chieti-Pescara, SS.Annunziata Hospital, Via dei Vestini, 66013 Chieti, Italy;
| | - Maurizio Onisto
- Department of Biomedical Sciences, University of Padova, Viale G. Colombo 3, 35121 Padova, Italy;
| | - Pietro Manuel Ferraro
- U.O.S. Terapia Conservativa della Malattia Renale Cronica, U.O.C. Nefrologia, Dipartimento di Scienze Mediche e Chirurgiche, Fondazione Policlinico Universitario A. Gemelli IRCCS, 00178 Rome, Italy;
- Dipartimento Universitario di Medicina e Chirurgia Traslazionale, Università Cattolica del Sacro Cuore, 00178 Rome, Italy
| | - Arduino Arduini
- R&D Department, Iperboreal Pharma Srl, 65122 Pescara, Italy;
| | - Giovanni Gambaro
- Division of Nephrology and Dialysis, Department of Medicine, Piazzale A. Stefani 1, 37126 Verona, Italy;
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Herzog R, Bartosova M, Tarantino S, Wagner A, Unterwurzacher M, Sacnun JM, Lichtenauer AM, Kuster L, Schaefer B, Alper SL, Aufricht C, Schmitt CP, Kratochwill K. Peritoneal Dialysis Fluid Supplementation with Alanyl-Glutamine Attenuates Conventional Dialysis Fluid-Mediated Endothelial Cell Injury by Restoring Perturbed Cytoprotective Responses. Biomolecules 2020; 10:biom10121678. [PMID: 33334074 PMCID: PMC7765520 DOI: 10.3390/biom10121678] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2020] [Revised: 12/09/2020] [Accepted: 12/12/2020] [Indexed: 12/18/2022] Open
Abstract
Long-term clinical outcome of peritoneal dialysis (PD) depends on adequate removal of small solutes and water. The peritoneal endothelium represents the key barrier and peritoneal transport dysfunction is associated with vascular changes. Alanyl-glutamine (AlaGln) has been shown to counteract PD-induced deteriorations but the effect on vascular changes has not yet been elucidated. Using multiplexed proteomic and bioinformatic analyses we investigated the molecular mechanisms of vascular pathology in-vitro (primary human umbilical vein endothelial cells, HUVEC) and ex-vivo (arterioles of patients undergoing PD) following exposure to PD-fluid. An overlap of 1813 proteins (40%) of over 3100 proteins was identified in both sample types. PD-fluid treatment significantly altered 378 in endothelial cells and 192 in arterioles. The HUVEC proteome resembles the arteriolar proteome with expected sample specific differences of mainly immune system processes only present in arterioles and extracellular region proteins primarily found in HUVEC. AlaGln-addition to PD-fluid revealed 359 differentially abundant proteins and restored the molecular process landscape altered by PD fluid. This study provides evidence on validity and inherent limitations of studying endothelial pathomechanisms in-vitro compared to vascular ex-vivo findings. AlaGln could reduce PD-associated vasculopathy by reducing endothelial cellular damage, restoring perturbed abundances of pathologically important proteins and enriching protective processes.
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Affiliation(s)
- Rebecca Herzog
- Division of Pediatric Nephrology and Gastroenterology, Department of Pediatrics and Adolescent Medicine, Comprehensive Center for Pediatrics, Medical University of Vienna, 1090 Vienna, Austria; (R.H.); (S.T.); (J.M.S.); (A.M.L.); (L.K.); (C.A.)
- Christian Doppler Laboratory for Molecular Stress Research in Peritoneal Dialysis, Medical University of Vienna, 1090 Vienna, Austria; (A.W.); (M.U.)
| | - Maria Bartosova
- Center for Pediatric and Adolescent Medicine, University of Heidelberg, 69120 Heidelberg, Germany; (M.B.); (B.S.); (C.P.S.)
| | - Silvia Tarantino
- Division of Pediatric Nephrology and Gastroenterology, Department of Pediatrics and Adolescent Medicine, Comprehensive Center for Pediatrics, Medical University of Vienna, 1090 Vienna, Austria; (R.H.); (S.T.); (J.M.S.); (A.M.L.); (L.K.); (C.A.)
- Zytoprotec GmbH, 1090 Vienna, Austria
| | - Anja Wagner
- Division of Pediatric Nephrology and Gastroenterology, Department of Pediatrics and Adolescent Medicine, Comprehensive Center for Pediatrics, Medical University of Vienna, 1090 Vienna, Austria; (R.H.); (S.T.); (J.M.S.); (A.M.L.); (L.K.); (C.A.)
- Christian Doppler Laboratory for Molecular Stress Research in Peritoneal Dialysis, Medical University of Vienna, 1090 Vienna, Austria; (A.W.); (M.U.)
| | - Markus Unterwurzacher
- Division of Pediatric Nephrology and Gastroenterology, Department of Pediatrics and Adolescent Medicine, Comprehensive Center for Pediatrics, Medical University of Vienna, 1090 Vienna, Austria; (R.H.); (S.T.); (J.M.S.); (A.M.L.); (L.K.); (C.A.)
- Christian Doppler Laboratory for Molecular Stress Research in Peritoneal Dialysis, Medical University of Vienna, 1090 Vienna, Austria; (A.W.); (M.U.)
| | - Juan Manuel Sacnun
- Division of Pediatric Nephrology and Gastroenterology, Department of Pediatrics and Adolescent Medicine, Comprehensive Center for Pediatrics, Medical University of Vienna, 1090 Vienna, Austria; (R.H.); (S.T.); (J.M.S.); (A.M.L.); (L.K.); (C.A.)
- Zytoprotec GmbH, 1090 Vienna, Austria
| | - Anton M. Lichtenauer
- Division of Pediatric Nephrology and Gastroenterology, Department of Pediatrics and Adolescent Medicine, Comprehensive Center for Pediatrics, Medical University of Vienna, 1090 Vienna, Austria; (R.H.); (S.T.); (J.M.S.); (A.M.L.); (L.K.); (C.A.)
| | - Lilian Kuster
- Division of Pediatric Nephrology and Gastroenterology, Department of Pediatrics and Adolescent Medicine, Comprehensive Center for Pediatrics, Medical University of Vienna, 1090 Vienna, Austria; (R.H.); (S.T.); (J.M.S.); (A.M.L.); (L.K.); (C.A.)
| | - Betti Schaefer
- Center for Pediatric and Adolescent Medicine, University of Heidelberg, 69120 Heidelberg, Germany; (M.B.); (B.S.); (C.P.S.)
| | - Seth L. Alper
- Division of Nephrology and Center for Vascular Biology Research, Beth Israel Deaconess Medical Center, Boston, MA 02215, USA;
- Department of Medicine, Harvard Medical School, Boston, MA 02115, USA
| | - Christoph Aufricht
- Division of Pediatric Nephrology and Gastroenterology, Department of Pediatrics and Adolescent Medicine, Comprehensive Center for Pediatrics, Medical University of Vienna, 1090 Vienna, Austria; (R.H.); (S.T.); (J.M.S.); (A.M.L.); (L.K.); (C.A.)
| | - Claus Peter Schmitt
- Center for Pediatric and Adolescent Medicine, University of Heidelberg, 69120 Heidelberg, Germany; (M.B.); (B.S.); (C.P.S.)
| | - Klaus Kratochwill
- Division of Pediatric Nephrology and Gastroenterology, Department of Pediatrics and Adolescent Medicine, Comprehensive Center for Pediatrics, Medical University of Vienna, 1090 Vienna, Austria; (R.H.); (S.T.); (J.M.S.); (A.M.L.); (L.K.); (C.A.)
- Christian Doppler Laboratory for Molecular Stress Research in Peritoneal Dialysis, Medical University of Vienna, 1090 Vienna, Austria; (A.W.); (M.U.)
- Correspondence: ; Tel.: +43-140400-80
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IL-17A as a Potential Therapeutic Target for Patients on Peritoneal Dialysis. Biomolecules 2020; 10:biom10101361. [PMID: 32987705 PMCID: PMC7598617 DOI: 10.3390/biom10101361] [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: 08/26/2020] [Revised: 09/16/2020] [Accepted: 09/22/2020] [Indexed: 12/13/2022] Open
Abstract
Chronic kidney disease (CKD) is a health problem reaching epidemic proportions. There is no cure for CKD, and patients may progress to end-stage renal disease (ESRD). Peritoneal dialysis (PD) is a current replacement therapy option for ESRD patients until renal transplantation can be achieved. One important problem in long-term PD patients is peritoneal membrane failure. The mechanisms involved in peritoneal damage include activation of the inflammatory and immune responses, associated with submesothelial immune infiltrates, angiogenesis, loss of the mesothelial layer due to cell death and mesothelial to mesenchymal transition, and collagen accumulation in the submesothelial compact zone. These processes lead to fibrosis and loss of peritoneal membrane function. Peritoneal inflammation and membrane failure are strongly associated with additional problems in PD patients, mainly with a very high risk of cardiovascular disease. Among the inflammatory mediators involved in peritoneal damage, cytokine IL-17A has recently been proposed as a potential therapeutic target for chronic inflammatory diseases, including CKD. Although IL-17A is the hallmark cytokine of Th17 immune cells, many other cells can also produce or secrete IL-17A. In the peritoneum of PD patients, IL-17A-secreting cells comprise Th17 cells, γδ T cells, mast cells, and neutrophils. Experimental studies demonstrated that IL-17A blockade ameliorated peritoneal damage caused by exposure to PD fluids. This article provides a comprehensive review of recent advances on the role of IL-17A in peritoneal membrane injury during PD and other PD-associated complications.
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Alanyl-Glutamine Restores Tight Junction Organization after Disruption by a Conventional Peritoneal Dialysis Fluid. Biomolecules 2020; 10:biom10081178. [PMID: 32823646 PMCID: PMC7464725 DOI: 10.3390/biom10081178] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2020] [Revised: 08/07/2020] [Accepted: 08/11/2020] [Indexed: 12/13/2022] Open
Abstract
Understanding and targeting the molecular basis of peritoneal solute and protein transport is essential to improve peritoneal dialysis (PD) efficacy and patient outcome. Supplementation of PD fluids (PDF) with alanyl-glutamine (AlaGln) increased small solute transport and reduced peritoneal protein loss in a recent clinical trial. Transepithelial resistance and 10 kDa and 70 kDa dextran transport were measured in primary human endothelial cells (HUVEC) exposed to conventional acidic, glucose degradation products (GDP) containing PDF (CPDF) and to low GDP containing PDF (LPDF) with and without AlaGln. Zonula occludens-1 (ZO-1) and claudin-5 were quantified by Western blot and immunofluorescence and in mice exposed to saline and CPDF for 7 weeks by digital imaging analyses. Spatial clustering of ZO-1 molecules was assessed by single molecule localization microscopy. AlaGln increased transepithelial resistance, and in CPDF exposed HUVEC decreased dextran transport rates and preserved claudin-5 and ZO-1 abundance. Endothelial clustering of membrane bound ZO-1 was higher in CPDF supplemented with AlaGln. In mice, arteriolar endothelial claudin-5 was reduced in CPDF, but restored with AlaGln, while mesothelial claudin-5 abundance was unchanged. AlaGln supplementation seals the peritoneal endothelial barrier, and when supplemented to conventional PD fluid increases claudin-5 and ZO-1 abundance and clustering of ZO-1 in the endothelial cell membrane.
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7
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Bonomini M, Borras FE, Troya-Saborido M, Carreras-Planella L, Di Liberato L, Arduini A. Proteomic Research in Peritoneal Dialysis. Int J Mol Sci 2020; 21:ijms21155489. [PMID: 32752018 PMCID: PMC7432538 DOI: 10.3390/ijms21155489] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Revised: 07/21/2020] [Accepted: 07/29/2020] [Indexed: 02/06/2023] Open
Abstract
Peritoneal dialysis (PD) is an established home care, cost-effective renal replacement therapy (RRT), which offers several advantages over the most used dialysis modality, hemodialysis. Despite its potential benefits, however, PD is an under-prescribed method of treating uremic patients. Infectious complications (primarily peritonitis) and bio-incompatibility of PD solutions are the main contributors to PD drop-out, due to their potential for altering the functional and anatomical integrity of the peritoneal membrane. To improve the clinical outcome of PD, there is a need for biomarkers to identify patients at risk of PD-related complications and to guide personalized interventions. Several recent studies have shown that proteomic investigation may be a powerful tool in the prediction, early diagnosis, prognostic assessment, and therapeutic monitoring of patients on PD. Indeed, analysis of the proteome present in PD effluent has uncovered several proteins involved in inflammation and pro-fibrotic insult, in encapsulating peritoneal sclerosis, or even in detecting early changes before any measurable modifications occur in the traditional clinical parameters used to evaluate PD efficacy. We here review the proteomic studies conducted thus far, addressing the potential use of such omics methodology in identifying potential new biomarkers of the peritoneal membrane welfare in relation to dialytic prescription and adequacy.
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Affiliation(s)
- Mario Bonomini
- Nephrology and Dialysis Unit, Department of Medicine, G. d’Annunzio University, Chieti-Pescara, SS. Annunziata Hospital, Via dei Vestini, 66013 Chieti, Italy;
- Correspondence:
| | - Francesc E. Borras
- Nephrology Department, Campus Can Ruti, Germans Trias i Pujol Research Institute (IGTP), REMAR-IGTP Group, Germans Trias i Pujol University Hospital, Carretera de Can Ruti, Camí de les Escoles s/n, 08916 Barcelona, Spain; (F.E.B.); (M.T.-S.); (L.C.-P.)
| | - Maribel Troya-Saborido
- Nephrology Department, Campus Can Ruti, Germans Trias i Pujol Research Institute (IGTP), REMAR-IGTP Group, Germans Trias i Pujol University Hospital, Carretera de Can Ruti, Camí de les Escoles s/n, 08916 Barcelona, Spain; (F.E.B.); (M.T.-S.); (L.C.-P.)
| | - Laura Carreras-Planella
- Nephrology Department, Campus Can Ruti, Germans Trias i Pujol Research Institute (IGTP), REMAR-IGTP Group, Germans Trias i Pujol University Hospital, Carretera de Can Ruti, Camí de les Escoles s/n, 08916 Barcelona, Spain; (F.E.B.); (M.T.-S.); (L.C.-P.)
| | - Lorenzo Di Liberato
- Nephrology and Dialysis Unit, Department of Medicine, G. d’Annunzio University, Chieti-Pescara, SS. Annunziata Hospital, Via dei Vestini, 66013 Chieti, Italy;
| | - Arduino Arduini
- Department of Research and Development, CoreQuest Sagl, Tecnopolo, 6934 Bioggio, Switzerland;
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Roumeliotis S, Dounousi E, Salmas M, Eleftheriadis T, Liakopoulos V. Unfavorable Effects of Peritoneal Dialysis Solutions on the Peritoneal Membrane: The Role of Oxidative Stress. Biomolecules 2020; 10:biom10050768. [PMID: 32423139 PMCID: PMC7277773 DOI: 10.3390/biom10050768] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2020] [Revised: 05/08/2020] [Accepted: 05/12/2020] [Indexed: 02/07/2023] Open
Abstract
One of the main limitations to successful long-term use of peritoneal dialysis (PD) as a renal replacement therapy is the harmful effects of PD solutions to the structure and function of the peritoneal membrane (PM). In PD, the PM serves as a semipermeable membrane that, due to exposure to PD solutions, undergoes structural alterations, including peritoneal fibrosis, vasculopathy, and neoangiogenesis. In recent decades, oxidative stress (OS) has emerged as a novel risk factor for mortality and cardiovascular disease in PD patients. Moreover, it has become evident that OS plays a pivotal role in the pathogenesis and development of the chronic, progressive injury of the PM. In this review, we aimed to present several aspects of OS in PD patients, including the pathophysiologic effects on the PM, clinical implications, and possible therapeutic antioxidant strategies that might protect the integrity of PM during PD therapy.
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Affiliation(s)
- Stefanos Roumeliotis
- Division of Nephrology and Hypertension, 1st Department of Internal Medicine, School of Medicine, Aristotle University of Thessaloniki, 54636 Thessaloniki, Greece;
| | - Evangelia Dounousi
- Department of Nephrology, Faculty of Medicine, School of Health Sciences, University of Ioannina, 45110 Ioannina, Greece;
| | - Marios Salmas
- Department of Anatomy, School of Medicine, National and Kapodistrian University of Athens, 11527 Athens, Greece;
| | | | - Vassilios Liakopoulos
- Division of Nephrology and Hypertension, 1st Department of Internal Medicine, School of Medicine, Aristotle University of Thessaloniki, 54636 Thessaloniki, Greece;
- Correspondence: ; Tel.: +30-2310-994-694
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Rohilla S, Dureja H, Chawla V. Cytoprotective Agents to Avoid Chemotherapy Induced Sideeffects on Normal Cells: A Review. Curr Cancer Drug Targets 2019; 19:765-781. [DOI: 10.2174/1568009619666190326120457] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2018] [Revised: 03/01/2019] [Accepted: 03/10/2019] [Indexed: 01/16/2023]
Abstract
Anticancer agents play a vital role in the cure of patients suffering from malignancy. Though, the chemotherapeutic agents are associated with various adverse effects which produce significant toxic symptoms in the patients. But this therapy affects both the malignant and normal cells and leads to constricted therapeutic index of antimalignant drugs which adversely impacts the quality of patients’ life. Due to these adversities, sufficient dose of drug is not delivered to patients leading to delay in treatment or improper treatment. Chemoprotective agents have been developed either to minimize or to mitigate the toxicity allied with chemotherapeutic agents. Without any concession in the therapeutic efficacy of anticancer drugs, they provide organ specific guard to normal tissues.
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Affiliation(s)
- Seema Rohilla
- Department of Pharmaceutics, Hindu College of Pharmacy, Sonepat- 131001, India
| | - Harish Dureja
- Department of Pharmaceutical Sciences, Maharshi Dayanand University, Rohtak-124001, India
| | - Vinay Chawla
- Institute of Pharmaceutical Sciences, Baba Farid University of Health Sciences, Faridkot-151203, India
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10
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Jiang N, Zhang Z, Shao X, Jing R, Wang C, Fang W, Mou S, Ni Z. Blockade of thrombospondin-1 ameliorates high glucose-induced peritoneal fibrosis through downregulation of TGF-β1/Smad3 signaling pathway. J Cell Physiol 2019; 235:364-379. [PMID: 31236971 DOI: 10.1002/jcp.28976] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2018] [Revised: 05/22/2019] [Accepted: 05/23/2019] [Indexed: 01/01/2023]
Abstract
BACKGROUND Transforming growth factor-β1 (TGF-β1) is a profibrotic cytokine which induces mesothelial cell mesothelial-to-mesenchymal transition (MMT) and peritoneal fibrosis in patients receiving treatment of peritoneal dialysis. Because thrombospondin-1 (TSP-1) is able to activate latent TGF-β1 in vivo, we investigated whether blockade of TSP-1 could modulate mesothelial cell MMT and ameliorate peritoneal fibrosis. METHODS Human pleural mesothelial cells (Met-5A cells) were treated with TSP-1 and addition of TGF-β1 neutralizing antibody to assess the effect of TSP-1 on MMT. Furthermore, TSP-1 blocking peptide Leu-Ser-Lys-Leu (LSKL) was applied to Met-5A cells treated with 4.25% d-glucose to determine its function in high glucose-induced MMT. Consequently, a uremic dialysate injection rat model was set up to confirm the results in vivo. RESULTS Exposure of Met-5A cells to TSP-1 increased TGF-β1 secretion, expression and bioactivity, triggered Smad3 phosphorylation, upregulated the expression of mesenchymal molecules including fibronectin, collagen type III, α-smooth muscle actin, Snail, and decreased calretinin expression. The effect was partially attenuated by TGF-β1 neutralizing antibody. TSP-1 expression in Met-5A cells was increased by 4.25% d-glucose, followed by increased secretion and bioactivity of TGF-β1, the onset of Smad3 phosphorylation and induction of MMT. LSKL significantly attenuated high glucose-mediated mesothelial cell MMT and ameliorated peritoneal fibrosis in uremic rats receiving dextrose dialysate injection. CONCLUSIONS Taken together, these data demonstrated that TSP-1 contributes to mesothelial cell MMT by activating TGF-β1/Smad3 signaling pathway and blockade of TSP-1 attenuates high glucose-mediated mesothelial cell MMT and peritoneal fibrosis.
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Affiliation(s)
- Na Jiang
- Department of Nephrology, Ren Ji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Zhen Zhang
- Department of Nephrology, Ren Ji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Xinghua Shao
- Department of Nephrology, Ren Ji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Ran Jing
- Department of Nephrology, Ren Ji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Chunlin Wang
- Department of Nephrology, Ren Ji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Wei Fang
- Department of Nephrology, Ren Ji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Shan Mou
- Department of Nephrology, Ren Ji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Zhaohui Ni
- Department of Nephrology, Ren Ji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
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11
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Boehm M, Herzog R, Klinglmüller F, Lichtenauer AM, Wagner A, Unterwurzacher M, Beelen RHJ, Alper SL, Aufricht C, Kratochwill K. The Peritoneal Surface Proteome in a Model of Chronic Peritoneal Dialysis Reveals Mechanisms of Membrane Damage and Preservation. Front Physiol 2019; 10:472. [PMID: 31156443 PMCID: PMC6530346 DOI: 10.3389/fphys.2019.00472] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2018] [Accepted: 04/04/2019] [Indexed: 12/31/2022] Open
Abstract
Peritoneal dialysis (PD) fluids are cytotoxic to the peritoneum. Recent studies have shown that alanyl-glutamine (AlaGln) modulates the cellular stress response, improves mesothelial cell survival, reduces submesothelial thickening in experimental models of PD, and in clinical studies improves PD effluent cell stress and immune responses. However, the mechanisms of AlaGln-mediated membrane protection are not yet fully understood. Here, we explore those mechanisms through application of a novel proteomics approach in a clinically relevant in vivo model in rats. Experimental PD was performed for 5 weeks using conventional single-chamber bag (SCB) or neutral dual-chamber bag (DCB), PD fluid (PDF), with or without AlaGln supplementation, via a surgically implanted catheter. Rats subjected to a single dwell without catheter implantation served as controls. The peritoneal surface proteome was directly harvested by detergent extraction and subjected to proteomic analysis by two-dimensional difference gel electrophoresis (2D-DiGE) with protein identification by mass spectrometry. An integrated bioinformatic approach was applied to identify proteins significantly affected by the treatments despite biological variation and interfering high abundance proteins. From 505 of 744 common spots on 59 gels, 222 unique proteins were identified. Using UniProt database information, proteins were assigned either as high abundance plasma proteins, or as cellular proteins. Statistical analysis employed an adapted workflow from RNA-sequencing, the trimmed mean of M-values (TMM) for normalization, and a mixed model for computational identification of significantly differentially abundant proteins. The most prominently enriched pathways after 5 weeks chronic treatment with SCB or DCB, PDFs belonged to clusters reflecting tissue damage and cell differentiation by cytoskeletal reorganization, immune responses, altered metabolism, and oxidative stress and redox homeostasis. Although the AlaGln effect was not as prominent, associated enriched pathways showed mostly regression to control or patterns opposite that of the PDF effect. Our study describes the novel peritoneal surface proteome through combined proteomic and bioinformatic analyses, and assesses changes elicited by chronic experimental PD. The biological processes so identified promise to link molecular mechanisms of membrane damage and protection in the in vivo rat model to pathomechanisms and cytoprotective effects observed in vitro and in clinical PD.
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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
| | - 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
| | - Florian Klinglmüller
- Center for Medical Statistics, Informatics, and Intelligent Systems-CeMSIIS, Medical University of Vienna, Vienna, Austria
| | - Anton M Lichtenauer
- Division of Pediatric Nephrology and Gastroenterology, Department of Pediatrics and Adolescent Medicine, Medical University of Vienna, Vienna, Austria
| | - Anja Wagner
- 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
| | - Markus Unterwurzacher
- 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
| | - Robert H J Beelen
- Department of Molecular Cell Biology and Immunology, VU University Medical Center, Amsterdam, Netherlands
| | - Seth L Alper
- Division of Nephrology, Beth Israel Deaconess Medical Center, Boston, MA, United States.,Department of Medicine, Harvard Medical School, Boston, MA, United States
| | - 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
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12
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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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13
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Wiesenhofer FM, Herzog R, Boehm M, Wagner A, Unterwurzacher M, Kasper DC, Alper SL, Vychytil A, Aufricht C, Kratochwill K. Targeted Metabolomic Profiling of Peritoneal Dialysis Effluents Shows Anti-oxidative Capacity of Alanyl-Glutamine. Front Physiol 2019; 9:1961. [PMID: 30719009 PMCID: PMC6348277 DOI: 10.3389/fphys.2018.01961] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2018] [Accepted: 12/28/2018] [Indexed: 01/25/2023] Open
Abstract
Readily available peritoneal dialysis (PD) effluents from PD patients in the course of renal replacement therapy are a potentially rich source for molecular markers for predicting clinical outcome, monitoring the therapy, and therapeutic interventions. The complex clinical phenotype of PD patients might be reflected in the PD effluent metabolome. Metabolomic analysis of PD effluent might allow quantitative detection and assessment of candidate PD biomarkers for prognostication and therapeutic monitoring. We therefore subjected peritoneal equilibration test effluents from 20 stable PD patients, obtained in a randomized controlled trial (RCT) to evaluate cytoprotective effects of standard PD solution (3.86% glucose) supplemented with 8 mM alanyl-glutamine (AlaGln) to targeted metabolomics analysis. One hundred eighty eight pre-defined metabolites, including free amino acids, acylcarnitines, and glycerophospholipids, as well as custom metabolic indicators calculated from these metabolites were surveyed in a high-throughput assay requiring only 10 μl of PD effluent. Metabolite profiles of effluents from the cross-over trial were analyzed with respect to AlaGln status and clinical parameters such as duration of PD therapy and history of previous episodes of peritonitis. This targeted approach detected and quantified 184 small molecules in PD effluent, a larger number of detected metabolites than in all previous metabolomic studies in PD effluent combined. Metabolites were clustered within substance classes regarding concentrations after a 4-h dwell. PD effluent metabolic profiles were differentiated according to PD patient sub-populations, revealing novel changes in small molecule abundance during PD therapy. AlaGln supplementation of PD fluid altered levels of specific metabolites, including increases in alanine and glutamine but not glutamate, and reduced levels of small molecule indicators of oxidative stress, such as methionine sulfoxide. Our study represents the first application of targeted metabolomics to PD effluents. The observed metabolomic changes in PD effluent associated with AlaGln-supplementation during therapy suggested an anti-oxidant effect, and were consistent with the restoration of important stress and immune processes previously noted in the RCT. High-throughput detection of PD effluent metabolomic signatures and their alterations by therapeutic interventions offers new opportunities for metabolome-clinical correlation in PD and for prescription of personalized PD therapy.
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Affiliation(s)
- Florian M Wiesenhofer
- Christian Doppler Laboratory for Molecular Stress Research in Peritoneal Dialysis, Department of Pediatrics and Adolescent Medicine, Medical University of Vienna, Vienna, Austria.,Division of Pediatric Nephrology and Gastroenterology, Department of Pediatrics and Adolescent Medicine, Medical University of Vienna, Vienna, Austria
| | - Rebecca Herzog
- Christian Doppler Laboratory for Molecular Stress Research in Peritoneal Dialysis, Department of Pediatrics and Adolescent Medicine, Medical University of Vienna, Vienna, Austria.,Division of Pediatric Nephrology and Gastroenterology, Department of Pediatrics and Adolescent Medicine, Medical University of Vienna, Vienna, Austria
| | - Michael Boehm
- Christian Doppler Laboratory for Molecular Stress Research in Peritoneal Dialysis, Department of Pediatrics and Adolescent Medicine, Medical University of Vienna, Vienna, Austria
| | - Anja Wagner
- Christian Doppler Laboratory for Molecular Stress Research in Peritoneal Dialysis, Department of Pediatrics and Adolescent Medicine, Medical University of Vienna, Vienna, Austria.,Division of Pediatric Nephrology and Gastroenterology, Department of Pediatrics and Adolescent Medicine, Medical University of Vienna, Vienna, Austria
| | - Markus Unterwurzacher
- Christian Doppler Laboratory for Molecular Stress Research in Peritoneal Dialysis, Department of Pediatrics and Adolescent Medicine, Medical University of Vienna, Vienna, Austria.,Division of Pediatric Nephrology and Gastroenterology, Department of Pediatrics and Adolescent Medicine, Medical University of Vienna, Vienna, Austria
| | | | - Seth L Alper
- Division of Nephrology and Vascular Biology Research Center, Beth Israel Deaconess Medical Center, Boston, MA, United States.,Department of Medicine, Harvard Medical School, Boston, MA, United States
| | - Andreas Vychytil
- Division of Nephrology and Dialysis, Department of Medicine III, 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
- Christian Doppler Laboratory for Molecular Stress Research in Peritoneal Dialysis, Department of Pediatrics and Adolescent Medicine, Medical University of Vienna, Vienna, Austria.,Division of Pediatric Nephrology and Gastroenterology, Department of Pediatrics and Adolescent Medicine, Medical University of Vienna, Vienna, Austria
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14
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Bartosova M, Schmitt CP. Biocompatible Peritoneal Dialysis: The Target Is Still Way Off. Front Physiol 2019; 9:1853. [PMID: 30700974 PMCID: PMC6343681 DOI: 10.3389/fphys.2018.01853] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2018] [Accepted: 12/07/2018] [Indexed: 01/01/2023] Open
Abstract
Peritoneal dialysis (PD) is a cost-effective, home-based therapy for patients with end-stage renal disease achieving similar outcome as compared to hemodialysis. Still, a minority of patients only receive PD. To a significant extend, this discrepancy is explained by major limitations regarding PD efficiency and sustainability. Due to highly unphysiological composition of PD fluids, the peritoneal membrane undergoes rapid morphological and long-term functional alterations, which limit the treatment and contribute to adverse patient outcome. This review is focused on the peritoneal membrane ultrastructure and its transformation in patients with kidney disease and chronic PD, underlying molecular mechanisms, and potential systemic sequelae. Current knowledge on the impact of conventional and second-generation PD fluids is described; novel strategies and innovative PD fluid types are discussed.
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Affiliation(s)
| | - Claus Peter Schmitt
- Center for Pediatric and Adolescent Medicine Heidelberg, University of Heidelberg, Heidelberg, Germany
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15
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Witowski J, Kamhieh-Milz J, Kawka E, Catar R, Jörres A. IL-17 in Peritoneal Dialysis-Associated Inflammation and Angiogenesis: Conclusions and Perspectives. Front Physiol 2018; 9:1694. [PMID: 30534087 PMCID: PMC6275317 DOI: 10.3389/fphys.2018.01694] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2018] [Accepted: 11/09/2018] [Indexed: 12/13/2022] Open
Abstract
Long-term peritoneal dialysis (PD) is associated with peritoneal membrane remodeling. This includes changes in peritoneal vasculature, which may ultimately lead to inadequate solute and water removal and treatment failure. The potential cause of such alterations is chronic inflammation induced by repeated episodes of infectious peritonitis and/or exposure to bioincompatible PD fluids. While these factors may jeopardize the peritoneal membrane integrity, it is not clear why adverse peritoneal remodeling develops only in some PD patients. Increasing evidence points to the differences that occur between patients in response to the same invading microorganism and/or the differences in the course of inflammatory reaction triggered by different species. Such differences may be related to the involvement of different inflammatory mediators. Here, we discuss the potential role of IL-17 in these processes with emphasis on its impact on peritoneal mesothelial cells and peritoneal vascularity.
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Affiliation(s)
- Janusz Witowski
- Department of Pathophysiology, Poznan University of Medical Sciences, Poznań, Poland.,Department of Nephrology, Medical Intensive Care, Charité - Universitätsmedizin Berlin, Berlin, Germany
| | - Julian Kamhieh-Milz
- Department of Transfusion Medicine, Charité - Universitätsmedizin Berlin, Berlin, Germany
| | - Edyta Kawka
- Department of Pathophysiology, Poznan University of Medical Sciences, Poznań, Poland
| | - Rusan Catar
- Department of Nephrology, Medical Intensive Care, Charité - Universitätsmedizin Berlin, Berlin, Germany.,Berlin Institute of Health, Berlin, Germany
| | - Achim Jörres
- Department of Medicine I, Nephrology, Transplantation, Medical Intensive Care, University of Witten/Herdecke, Cologne-Merheim Medical Center, Cologne, Germany
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16
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Vychytil A, Herzog R, Probst P, Ribitsch W, Lhotta K, Machold-Fabrizii V, Wiesholzer M, Kaufmann M, Salmhofer H, Windpessl M, Rosenkranz AR, Oberbauer R, König F, Kratochwill K, Aufricht C. A randomized controlled trial of alanyl-glutamine supplementation in peritoneal dialysis fluid to assess impact on biomarkers of peritoneal health. Kidney Int 2018; 94:1227-1237. [PMID: 30360960 DOI: 10.1016/j.kint.2018.08.031] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2018] [Revised: 07/25/2018] [Accepted: 08/09/2018] [Indexed: 01/26/2023]
Abstract
In early clinical testing, acute addition of alanyl-glutamine (AlaGln) to glucose-based peritoneal dialysis (PD) fluids restored peritoneal cellular stress responses and leukocyte function. This study was designed to test the effect of extended treatment with AlaGln-supplemented PD fluid on biomarkers of peritoneal health. In a double-blinded, randomized crossover design, stable PD patients were treated with AlaGln (8 mM) or placebo added to PD fluid for eight weeks. As primary outcome measures, dialysate cancer-antigen 125 (CA-125) appearance rate and ex vivo stimulated interleukin-6 (IL-6) release were assessed in peritoneal equilibration tests. In 8 Austrian centers, 54 patients were screened, 50 randomized, and 41 included in the full analysis set. AlaGln supplementation significantly increased CA-125 appearance rate and ex vivo stimulated IL-6 release. AlaGln supplementation also reduced peritoneal protein loss, increased ex vivo stimulated tumor necrosis factor (TNF)-α release, and reduced systemic IL-8 levels. No adverse safety signals were observed. All 4 peritonitis episodes occurred during standard PD fluid treatment. A novel AlaGln-supplemented PD fluid improves biomarkers of peritoneal membrane integrity, immune competence, and systemic inflammation compared to unsupplemented PD fluid with neutral pH and low-glucose degradation. A phase 3 trial is needed to determine the impact of AlaGln supplementation on hard clinical outcomes.
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Affiliation(s)
- Andreas Vychytil
- Department of Medicine III, Division of Nephrology and Dialysis, Medical University of Vienna, Vienna, Austria.
| | - Rebecca Herzog
- Department of Pediatrics and Adolescent Medicine, Division of Pediatric Nephrology and Gastroenterology, Medical University of Vienna, Vienna, Austria; Christian Doppler Laboratory for Molecular Stress Research in Peritoneal Dialysis, Medical University of Vienna, Vienna, Austria
| | - Paul Probst
- Department of Medicine III, Division of Nephrology and Dialysis, Medical University of Vienna, Vienna, Austria
| | - Werner Ribitsch
- Department of Internal Medicine, Clinical Division of Nephrology, Medical University of Graz, Graz, Austria
| | - Karl Lhotta
- Department of Internal Medicine 3 (Nephrology and Dialysis), Feldkirch Academic Teaching Hospital, Feldkirch, Austria
| | | | - Martin Wiesholzer
- Department of Internal Medicine I, University Hospital St. Poelten, Karl Landsteiner University of Health Sciences, St. Poelten, Austria
| | - Michaela Kaufmann
- Department of Medicine III, Nephrology, Transplantation, Rheumatology, Geriatrics, Ordensklinikum Linz, Krankenhaus der Elisabethinen Linz, Linz, Austria
| | - Hermann Salmhofer
- Department of Medicine I, Paracelsus Medical University, Salzburg, Austria
| | - Martin Windpessl
- Department of Internal Medicine IV, Klinikum Wels-Grieskirchen, Wels, Austria
| | - Alexander R Rosenkranz
- Department of Internal Medicine, Clinical Division of Nephrology, Medical University of Graz, Graz, Austria
| | - Rainer Oberbauer
- Department of Medicine III, Division of Nephrology and Dialysis, Medical University of Vienna, Vienna, Austria
| | - Franz König
- Center for Medical Statistics, Informatics and Intelligent Systems, Medical University of Vienna, Vienna, Austria
| | - Klaus Kratochwill
- Department of Pediatrics and Adolescent Medicine, Division of Pediatric Nephrology and Gastroenterology, Medical University of Vienna, Vienna, Austria; Christian Doppler Laboratory for Molecular Stress Research in Peritoneal Dialysis, Medical University of Vienna, Vienna, Austria
| | - Christoph Aufricht
- Department of Pediatrics and Adolescent Medicine, Division of Pediatric Nephrology and Gastroenterology, Medical University of Vienna, Vienna, Austria
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17
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Peritoneal dialysis beyond kidney failure? J Control Release 2018; 282:3-12. [DOI: 10.1016/j.jconrel.2018.01.017] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2017] [Accepted: 01/17/2018] [Indexed: 12/19/2022]
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18
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Targeting Toll-like receptors with soluble Toll-like receptor 2 prevents peritoneal dialysis solution-induced fibrosis. Kidney Int 2018; 94:346-362. [PMID: 29861057 DOI: 10.1016/j.kint.2018.03.014] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2017] [Revised: 03/05/2018] [Accepted: 03/15/2018] [Indexed: 12/13/2022]
Abstract
Peritoneal membrane failure due to fibrosis limits the use of peritoneal dialysis (PD). Peritoneal fibrosis may potentially be induced by sterile inflammation caused by ongoing cellular stress due to prolonged exposure to PD solutions (PDS). Effective therapies to prevent this process remain to be developed. Toll-like receptors (TLRs) mediate sterile inflammation by recognizing damage-associated molecular patterns (DAMPs) released by cellular stress. We evaluated the involvement of TLRs and DAMPs in PDS-induced fibrosis models and the therapeutic potential of TLR-DAMP targeting for preventing fibrosis. A range of PDS elicited pro-inflammatory and fibrotic responses from PD patient peritoneal leukocytes, mesothelial cells and mouse peritoneal leukocytes. TLR2/4 blockade of human peritoneal cells or TLR2/4 knockouts inhibited these effects. PDS did not induce rapid ERK phosphorylation or IκB-α degradation, suggesting that they do not contain components capable of direct TLR activation. However, PDS increased the release of Hsp70 and hyaluronan, both TLR2/4 DAMP ligands, by human and mouse peritoneal cells, and their blockade decreased PDS-driven inflammation. Soluble TLR2, a TLR inhibitor, reduced PDS-induced pro-inflammatory and fibrotic cytokine release ex vivo. Daily catheter infusion of PDS in mice caused peritoneal fibrosis, but co-administration of soluble TLR2 prevented fibrosis, suppressed pro-fibrotic gene expression and pro-inflammatory cytokine production, reduced leukocyte/neutrophil recruitment, recovered Treg cell levels and increased the Treg:Th17 ratio. Thus, TLR2/4, Hsp70 and hyaluronan showed major roles in PDS-induced peritoneal inflammation and fibrosis. The study demonstrates the therapeutic potential of a TLR-DAMP targeting strategy to prevent PDS-induced fibrosis.
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19
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Schneider KH, Enayati M, Grasl C, Walter I, Budinsky L, Zebic G, Kaun C, Wagner A, Kratochwill K, Redl H, Teuschl AH, Podesser BK, Bergmeister H. Acellular vascular matrix grafts from human placenta chorion: Impact of ECM preservation on graft characteristics, protein composition and in vivo performance. Biomaterials 2018; 177:14-26. [PMID: 29885585 DOI: 10.1016/j.biomaterials.2018.05.045] [Citation(s) in RCA: 45] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2018] [Revised: 05/18/2018] [Accepted: 05/26/2018] [Indexed: 02/06/2023]
Abstract
Small diameter vascular grafts from human placenta, decellularized with either Triton X-100 (Triton) or SDS and crosslinked with heparin were constructed and characterized. Graft biochemical properties, residual DNA, and protein composition were evaluated to compare the effect of the two detergents on graft matrix composition and structural alterations. Biocompatibility was tested in vitro by culturing the grafts with primary human macrophages and in vivo by subcutaneous implantation of graft conduits (n = 7 per group) into the flanks of nude rats. Subsequently, graft performance was evaluated using an aortic implantation model in Sprague Dawley rats (one month, n = 14). In situ graft imaging was performed using MRI angiography. Retrieved specimens were analyzed by electromyography, scanning electron microscopy, histology and immunohistochemistry to evaluate cell migration and the degree of functional tissue remodeling. Both decellularization methods resulted in grafts of excellent biocompatibility in vitro and in vivo, with low immunogenic potential. Proteomic data revealed removal of cytoplasmic proteins with relative enrichment of ECM proteins in decelluarized specimens of both groups. Noteworthy, LC-Mass Spectrometry analysis revealed that 16 proteins were exclusively preserved in Triton decellularized specimens in comparison to SDS-treated specimens. Aortic grafts showed high patency rates, no signs of thrombus formation, aneurysms or rupture. Conduits of both groups revealed tissue-specific cell migration indicative of functional remodeling. This study strongly suggests that decellularized allogenic grafts from the human placenta have the potential to be used as vascular replacement materials. Both detergents produced grafts with low residual immunogenicity and appropriate mechanical properties. Observed differences in graft characteristics due to preservation method had no impact on successful in vivo performance in the rodent model.
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Affiliation(s)
- Karl H Schneider
- Ludwig Boltzmann Cluster for Cardiovascular Research, Vienna, Austria; Center for Biomedical Research Medical University of Vienna, Vienna, Austria; Austrian Cluster for Tissue Regeneration, Vienna, Austria
| | - Marjan Enayati
- Ludwig Boltzmann Cluster for Cardiovascular Research, Vienna, Austria; Center for Biomedical Research Medical University of Vienna, Vienna, Austria
| | - Christian Grasl
- Center for Biomedical Research Medical University of Vienna, Vienna, Austria; Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Austria
| | - Ingrid Walter
- Department of Pathobiology, University of Veterinary Medicine Vienna, Vienna, Austria
| | - Lubos Budinsky
- Preclinical Imaging Laboratory, Division of Molecular and Gender Imaging, Department of Biomedical Imaging and Image-guided Therapy, Medical University of Vienna, Vienna, Austria
| | - Gabriel Zebic
- Center for Biomedical Research Medical University of Vienna, Vienna, Austria
| | - Christoph Kaun
- Division of Internal Medicine II, Medical University of Vienna, Vienna, Austria
| | - Anja Wagner
- Department of Pediatric and Adolescent Medicine, Medical University of Vienna, Vienna, Austria; Christian Doppler Laboratory for Molecular Stress Research in Peritoneal Dialysis, Vienna, Austria
| | - Klaus Kratochwill
- Department of Pediatric and Adolescent Medicine, Medical University of Vienna, Vienna, Austria; Christian Doppler Laboratory for Molecular Stress Research in Peritoneal Dialysis, Vienna, Austria
| | - Heinz Redl
- Ludwig Boltzmann Institute for Experimental and Clinical Traumatology in AUVA Trauma Center, Vienna, Austria; Austrian Cluster for Tissue Regeneration, Vienna, Austria
| | - Andreas H Teuschl
- Department of Biochemical Engineering, University of Applied Sciences Technikum Wien, Vienna, Austria; Austrian Cluster for Tissue Regeneration, Vienna, Austria; City of Vienna Competence Team Siganltransduction, Vienna, Austria
| | - Bruno K Podesser
- Ludwig Boltzmann Cluster for Cardiovascular Research, Vienna, Austria; Center for Biomedical Research Medical University of Vienna, Vienna, Austria; Austrian Cluster for Tissue Regeneration, Vienna, Austria
| | - Helga Bergmeister
- Ludwig Boltzmann Cluster for Cardiovascular Research, Vienna, Austria; Center for Biomedical Research Medical University of Vienna, Vienna, Austria; Austrian Cluster for Tissue Regeneration, Vienna, Austria.
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Abstract
Peritoneal dialysis (PD) is a successfully used method for renal replacement therapy. However, long-term PD may be associated with peritoneal fibrosis and ultrafiltration failure. The key factors linked to their appearance are repeated episodes of inflammation associated with peritonitis and long-term exposure to bioincompatible PD fluids. Different strategies have been proposed to preserve the peritoneal membrane. This article reviews the functional and structural alterations related to PD and strategies whereby we may prevent them to preserve the peritoneal membrane. The use of new, more biocompatible, PD solutions is promising, although further morphologic studies in patients using these solutions are needed. Blockade of the renin-angiotensin-aldosterone system appears to be efficacious and strongly should be considered. Other agents have been proven in experimental studies, but most of them have not yet been tested appropriately in human beings.
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Affiliation(s)
- M Auxiliadora Bajo
- Home Dialysis Unit, Nephrology Department, La Paz University Hospital, Madrid, Spain.
| | - Gloria Del Peso
- University Autónoma of Madrid, Hospital La Paz Institute for Health Research, Spanish Renal Research Network, Reina Sofia Institute for Nephrology Research, Madrid, Spain
| | - Isaac Teitelbaum
- Home Dialysis Program, University of Colorado Hospital, University of Colorado School of Medicine, Aurora, CO
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21
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Herzog R, Boehm M, Unterwurzacher M, Wagner A, Parapatics K, Májek P, Mueller AC, Lichtenauer A, Bennett KL, Alper SL, Vychytil A, Aufricht C, Kratochwill K. Effects of Alanyl-Glutamine Treatment on the Peritoneal Dialysis Effluent Proteome Reveal Pathomechanism-Associated Molecular Signatures. Mol Cell Proteomics 2017; 17:516-532. [PMID: 29208752 PMCID: PMC5836375 DOI: 10.1074/mcp.ra117.000186] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2017] [Revised: 11/16/2017] [Indexed: 12/21/2022] Open
Abstract
Peritoneal dialysis (PD) is a modality of renal replacement therapy in which the high volumes of available PD effluent (PDE) represents a rich source of biomarkers for monitoring disease and therapy. Although this information could help guide the management of PD patients, little is known about the potential of PDE to define pathomechanism-associated molecular signatures in PD. We therefore subjected PDE to a high-performance multiplex proteomic analysis after depletion of highly-abundant plasma proteins and enrichment of low-abundance proteins. A combination of label-free and isobaric labeling strategies was applied to PDE samples from PD patients (n = 20) treated in an open-label, randomized, two-period, cross-over clinical trial with standard PD fluid or with a novel PD fluid supplemented with alanyl-glutamine (AlaGln). With this workflow we identified 2506 unique proteins in the PDE proteome, greatly increasing coverage beyond the 171 previously-reported proteins. The proteins identified range from high abundance plasma proteins to low abundance cellular proteins, and are linked to larger numbers of biological processes and pathways, some of which are novel for PDE. Interestingly, proteins linked to membrane remodeling and fibrosis are overrepresented in PDE compared with plasma, whereas the proteins underrepresented in PDE suggest decreases in host defense, immune-competence and response to stress. Treatment with AlaGln-supplemented PD fluid is associated with reduced activity of membrane injury-associated mechanisms and with restoration of biological processes involved in stress responses and host defense. Our study represents the first application of the PDE proteome in a randomized controlled prospective clinical trial of PD. This novel proteomic workflow allowed detection of low abundance biomarkers to define pathomechanism-associated molecular signatures in PD and their alterations by a novel therapeutic intervention.
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Affiliation(s)
- Rebecca Herzog
- From the ‡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
| | - Michael Boehm
- From the ‡Division of Pediatric Nephrology and Gastroenterology, Department of Pediatrics and Adolescent Medicine, Medical University of Vienna, Vienna, Austria
| | - Markus Unterwurzacher
- From the ‡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
| | - Anja Wagner
- From the ‡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
| | - Katja Parapatics
- ¶CeMM Research Center for Molecular Medicine of the Austrian Academy of Sciences, Vienna, Austria
| | - Peter Májek
- ¶CeMM Research Center for Molecular Medicine of the Austrian Academy of Sciences, Vienna, Austria
| | - André C Mueller
- ¶CeMM Research Center for Molecular Medicine of the Austrian Academy of Sciences, Vienna, Austria
| | - Anton Lichtenauer
- From the ‡Division of Pediatric Nephrology and Gastroenterology, Department of Pediatrics and Adolescent Medicine, Medical University of Vienna, Vienna, Austria
| | - Keiryn L Bennett
- ¶CeMM Research Center for Molecular Medicine of the Austrian Academy of Sciences, Vienna, Austria
| | - Seth L Alper
- ‖Division of Nephrology, Beth Israel Deaconess Medical Center, Boston, Massachusetts.,**Department of Medicine, Harvard Medical School, Boston, Massachusetts
| | - Andreas Vychytil
- ‡‡Department of Medicine III, Division of Nephrology and Dialysis, Medical University of Vienna, Vienna, Austria
| | - Christoph Aufricht
- From the ‡Division of Pediatric Nephrology and Gastroenterology, Department of Pediatrics and Adolescent Medicine, Medical University of Vienna, Vienna, Austria
| | - Klaus Kratochwill
- From the ‡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
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22
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Biomarker research to improve clinical outcomes of peritoneal dialysis: consensus of the European Training and Research in Peritoneal Dialysis (EuTRiPD) network. Kidney Int 2017; 92:824-835. [PMID: 28797473 DOI: 10.1016/j.kint.2017.02.037] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2016] [Revised: 02/16/2017] [Accepted: 02/27/2017] [Indexed: 12/15/2022]
Abstract
Peritoneal dialysis (PD) therapy substantially requires biomarkers as tools to identify patients who are at the highest risk for PD-related complications and to guide personalized interventions that may improve clinical outcome in the individual patient. In this consensus article, members of the European Training and Research in Peritoneal Dialysis Network (EuTRiPD) review the current status of biomarker research in PD and suggest a selection of biomarkers that can be relevant to the care of PD patients and that are directly accessible in PD effluents. Currently used biomarkers such as interleukin-6, interleukin-8, ex vivo-stimulated interleukin-6 release, cancer antigen-125, and advanced oxidation protein products that were collected through a Delphi procedure were first triaged for inclusion as surrogate endpoints in a clinical trial. Next, novel biomarkers were selected as promising candidates for proof-of-concept studies and were differentiated into inflammation signatures (including interleukin-17, M1/M2 macrophages, and regulatory T cell/T helper 17), mesothelial-to-mesenchymal transition signatures (including microRNA-21 and microRNA-31), and signatures for senescence and inadequate cellular stress responses. Finally, the need for defining pathogen-specific immune fingerprints and phenotype-associated molecular signatures utilizing effluents from the clinical cohorts of PD patients and "omics" technologies and bioinformatics-biostatistics in future joint-research efforts was expressed. Biomarker research in PD offers the potential to develop valuable tools for improving patient management. However, for all biomarkers discussed in this consensus article, the association of biological rationales with relevant clinical outcomes remains to be rigorously validated in adequately powered, prospective, independent clinical studies.
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23
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Is there such a thing as biocompatible peritoneal dialysis fluid? Pediatr Nephrol 2017; 32:1835-1843. [PMID: 27722783 PMCID: PMC5579143 DOI: 10.1007/s00467-016-3461-y] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/04/2016] [Revised: 07/01/2016] [Accepted: 07/01/2016] [Indexed: 10/31/2022]
Abstract
Introduction of the so-called biocompatible peritoneal dialysis (PD) fluids was based on a large body of experimental evidence and various clinical trials suggesting important clinical benefits. Of these, until now, only preservation of residual renal function-likely due to lower glucose degradation product load and, in case of icodextrin, improved fluid and blood pressure control-have consistently been proven, whereas the impact on important clinical endpoints such as infectious complications, preservation of PD membrane transport function, and patient outcome, are still debated. In view of the high morbidity and mortality rates of PD patients, novel approaches are warranted and comprise the search for alternative osmotic agents and enrichment of PD fluids with specific pharmacologic agents, such as alanyl-glutamine, potentially counteracting local but also systemic sequelae of uremia and PD.
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24
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Kratochwill K, Boehm M, Herzog R, Gruber K, Lichtenauer AM, Kuster L, Csaicsich D, Gleiss A, Alper SL, Aufricht C, Vychytil A. Addition of Alanyl-Glutamine to Dialysis Fluid Restores Peritoneal Cellular Stress Responses - A First-In-Man Trial. PLoS One 2016; 11:e0165045. [PMID: 27768727 PMCID: PMC5074513 DOI: 10.1371/journal.pone.0165045] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2016] [Accepted: 10/01/2016] [Indexed: 12/14/2022] Open
Abstract
BACKGROUND Peritonitis and ultrafiltration failure remain serious complications of chronic peritoneal dialysis (PD). Dysfunctional cellular stress responses aggravate peritoneal injury associated with PD fluid exposure, potentially due to peritoneal glutamine depletion. In this randomized cross-over phase I/II trial we investigated cytoprotective effects of alanyl-glutamine (AlaGln) addition to glucose-based PDF. METHODS In a prospective randomized cross-over design, 20 stable PD outpatients underwent paired peritoneal equilibration tests 4 weeks apart, using conventional acidic, single chamber 3.86% glucose PD fluid, with and without 8 mM supplemental AlaGln. Heat-shock protein 72 expression was assessed in peritoneal effluent cells as surrogate parameter of cellular stress responses, complemented by metabolomics and functional immunocompetence assays. RESULTS AlaGln restored peritoneal glutamine levels and increased the primary outcome heat-shock protein expression (effect 1.51-fold, CI 1.07-2.14; p = 0.022), without changes in peritoneal ultrafiltration, small solute transport, or biomarkers reflecting cell mass and inflammation. Further effects were glutamine-like metabolomic changes and increased ex-vivo LPS-stimulated cytokine release from healthy donor peripheral blood monocytes. In patients with a history of peritonitis (5 of 20), AlaGln supplementation decreased dialysate interleukin-8 levels. Supplemented PD fluid also attenuated inflammation and enhanced stimulated cytokine release in a mouse model of PD-associated peritonitis. CONCLUSION We conclude that AlaGln-supplemented, glucose-based PD fluid can restore peritoneal cellular stress responses with attenuation of sterile inflammation, and may improve peritoneal host-defense in the setting of PD.
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Affiliation(s)
- 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
- Zytoprotec GmbH, Vienna, Austria
| | - Michael Boehm
- Division of Pediatric Nephrology and Gastroenterology, Department of Pediatrics and Adolescent Medicine, 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
- Zytoprotec GmbH, Vienna, Austria
| | - Katharina Gruber
- Division of Pediatric Nephrology and Gastroenterology, Department of Pediatrics and Adolescent Medicine, Medical University of Vienna, Vienna, Austria
| | - Anton Michael Lichtenauer
- Division of Pediatric Nephrology and Gastroenterology, Department of Pediatrics and Adolescent Medicine, Medical University of Vienna, Vienna, Austria
- Zytoprotec GmbH, Vienna, Austria
| | - Lilian Kuster
- Division of Pediatric Nephrology and Gastroenterology, Department of Pediatrics and Adolescent Medicine, Medical University of Vienna, Vienna, Austria
- Zytoprotec GmbH, Vienna, Austria
| | - Dagmar Csaicsich
- Division of Pediatric Nephrology and Gastroenterology, Department of Pediatrics and Adolescent Medicine, Medical University of Vienna, Vienna, Austria
| | - Andreas Gleiss
- Center for Medical Statistics, Informatics, and Intelligent Systems, Medical University of Vienna, Vienna, Austria
| | - Seth L. Alper
- Division of Nephrology and Center for Vascular Biology Research, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Christoph Aufricht
- Division of Pediatric Nephrology and Gastroenterology, Department of Pediatrics and Adolescent Medicine, Medical University of Vienna, Vienna, Austria
| | - Andreas Vychytil
- Division of Nephrology and Dialysis, Medical University of Vienna, Vienna, Austria
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25
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Csaicsich D, Lichtenauer AM, Vychytil A, Kasper DC, Herzog R, Aufricht C, Kratochwill K. Feasibility of Metabolomics Analysis of Dialysate Effluents from Patients Undergoing Peritoneal Equilibration Testing. Perit Dial Int 2016; 35:590-2. [PMID: 26450481 DOI: 10.3747/pdi.2014.00118] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Affiliation(s)
- Dagmar Csaicsich
- Department of Pediatrics and Adolescent Medicine, Medical University of Vienna, Vienna, Austria
| | - Anton M Lichtenauer
- Department of Pediatrics and Adolescent Medicine, Medical University of Vienna, Vienna, Austria Zytoprotec GmbH, Vienna, Austria
| | - Andreas Vychytil
- Division of Nephrology and Dialysis, Medical University of Vienna, Vienna, Austria
| | - David C Kasper
- Department of Pediatrics and Adolescent Medicine, Medical University of Vienna, Vienna, Austria
| | - Rebecca Herzog
- Department of Pediatrics and Adolescent Medicine, Medical University of Vienna, Vienna, Austria Zytoprotec GmbH, Vienna, Austria
| | - Christoph Aufricht
- Department of Pediatrics and Adolescent Medicine, Medical University of Vienna, Vienna, Austria
| | - Klaus Kratochwill
- Department of Pediatrics and Adolescent Medicine, Medical University of Vienna, Vienna, Austria Zytoprotec GmbH, Vienna, Austria
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26
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Ferrantelli E, Liappas G, Vila Cuenca M, Keuning ED, Foster TL, Vervloet MG, Lopéz-Cabrera M, Beelen RHJ. The dipeptide alanyl-glutamine ameliorates peritoneal fibrosis and attenuates IL-17 dependent pathways during peritoneal dialysis. Kidney Int 2016; 89:625-35. [PMID: 26880457 DOI: 10.1016/j.kint.2015.12.005] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2014] [Revised: 09/11/2015] [Accepted: 09/24/2015] [Indexed: 01/07/2023]
Abstract
Peritoneal dialysis (PD) can result in chronic inflammation and progressive peritoneal membrane damage. Alanyl-Glutamine (Ala-Gln), a dipeptide with immunomodulatory effects, improved resistance of mesothelial cells to PD fluids. Recently, interleukin-17 (IL-17) was found to be associated with PD-induced peritoneal damage. Here we studied the capacity of intraperitoneal Ala-Gln administration to protect against peritoneal damage by modulating IL-17 expression in uremic rat and mouse PD exposure models. Supplementation of PD fluid with Ala-Gln resulted in reduced peritoneal thickness, αSMA expression and angiogenesis. Addition of Ala-Gln also attenuated the IL-17 pathway expression induced by PD, reflected by substantial reduction or normalization of peritoneal levels of IL-17, transforming growth factor β, IL-6, and the transcription factor retinoic acid receptor-related orphan receptor gamma T. Moreover, increased levels of IL-17 were associated with PD-induced peritoneal thickening. Conversely, Ala-Gln treatment prevented peritoneal extracellular matrix deposition, an effect seen with IL-17 blockade. Thus, intraperitoneal administration of Ala-Gln, a stable dipeptide commonly used in parenteral nutrition, ameliorates PD-induced peritoneal damage in animal models, in part by modulating IL-17 expression. Hence, Ala-Gln supplementation of dialysate may be a potential strategy to ameliorate peritoneal deterioration during PD.
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Affiliation(s)
- Evelina Ferrantelli
- Department of Molecular Cell Biology and Immunology, VU University Medical Center, Amsterdam, The Netherlands
| | - Georgios Liappas
- Centro de Biología Molecular Severo Ochoa, CSIC-UAM, Madrid, Spain
| | - Marc Vila Cuenca
- Department of Molecular Cell Biology and Immunology, VU University Medical Center, Amsterdam, The Netherlands
| | - Eelco D Keuning
- Department of Molecular Cell Biology and Immunology, VU University Medical Center, Amsterdam, The Netherlands
| | - Thomas L Foster
- Department of Molecular Cell Biology and Immunology, VU University Medical Center, Amsterdam, The Netherlands
| | - Marc G Vervloet
- Department of Nephrology, VU University Medical Center Amsterdam, The Netherlands
| | | | - Robert H J Beelen
- Department of Molecular Cell Biology and Immunology, VU University Medical Center, Amsterdam, The Netherlands.
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Senescence-Associated Changes in Proteome and O-GlcNAcylation Pattern in Human Peritoneal Mesothelial Cells. BIOMED RESEARCH INTERNATIONAL 2015; 2015:382652. [PMID: 26640786 PMCID: PMC4657062 DOI: 10.1155/2015/382652] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/22/2015] [Revised: 10/24/2015] [Accepted: 10/25/2015] [Indexed: 12/17/2022]
Abstract
INTRODUCTION Senescence of peritoneal mesothelial cells represents a biological program defined by arrested cell growth and altered cell secretory phenotype with potential impact in peritoneal dialysis. This study aims to characterize cellular senescence at the level of global protein expression profiles and modification of proteins with O-linked N-acetylglucosamine (O-GlcNAcylation). METHODS A comparative proteomics analysis between young and senescent human peritoneal mesothelial cells (HPMC) was performed using two-dimensional gel electrophoresis. O-GlcNAc status was assessed by Western blot under normal conditions and after modulation with 6-diazo-5-oxo-L-norleucine (DON) to decrease O-GlcNAcylation or O-(2-acetamido-2-deoxy-D-glucopyranosylidene) amino N-phenyl carbamate (PUGNAc) to increase O-GlcNAcylation. RESULTS Comparison of protein pattern of senescent and young HPMC revealed 29 differentially abundant protein spots, 11 of which were identified to be actin (cytoplasmic 1 and 2), cytokeratin-7, cofilin-2, transgelin-2, Hsp60, Hsc70, proteasome β-subunits (type-2 and type-3), nucleoside diphosphate kinase A, and cytosolic 5'(3')-deoxyribonucleotidase. Although the global level of O-GlcNAcylation was comparable, senescent cells were not sensitive to modulation by PUGNAc. DISCUSSION This study identified changes of the proteome and altered dynamics of O-GlcNAc regulation in senescent mesothelial cells. Whereas changes in cytoskeleton-associated proteins likely reflect altered cell morphology, changes in chaperoning and housekeeping proteins may have functional impact on cellular stress response in peritoneal dialysis.
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Cross-omics comparison of stress responses in mesothelial cells exposed to heat- versus filter-sterilized peritoneal dialysis fluids. BIOMED RESEARCH INTERNATIONAL 2015; 2015:628158. [PMID: 26495307 PMCID: PMC4606138 DOI: 10.1155/2015/628158] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/13/2015] [Accepted: 08/31/2015] [Indexed: 02/06/2023]
Abstract
Recent research suggests that cytoprotective responses, such as expression of heat-shock proteins, might be inadequately induced in mesothelial cells by heat-sterilized peritoneal dialysis (PD) fluids. This study compares transcriptome data and multiple protein expression profiles for providing new insight into regulatory mechanisms. Two-dimensional difference gel electrophoresis (2D-DIGE) based proteomics and topic defined gene expression microarray-based transcriptomics techniques were used to evaluate stress responses in human omental peritoneal mesothelial cells in response to heat- or filter-sterilized PD fluids. Data from selected heat-shock proteins were validated by 2D western-blot analysis. Comparison of proteomics and transcriptomics data discriminated differentially regulated protein abundance into groups depending on correlating or noncorrelating transcripts. Inadequate abundance of several heat-shock proteins following exposure to heat-sterilized PD fluids is not reflected on the mRNA level indicating interference beyond transcriptional regulation. For the first time, this study describes evidence for posttranscriptional inadequacy of heat-shock protein expression by heat-sterilized PD fluids as a novel cytotoxic property. Cross-omics technologies introduce a novel way of understanding PDF bioincompatibility and searching for new interventions to reestablish adequate cytoprotective responses.
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29
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Janus kinase signaling activation mediates peritoneal inflammation and injury in vitro and in vivo in response to dialysate. Kidney Int 2014; 86:1187-96. [PMID: 25007168 DOI: 10.1038/ki.2014.209] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2014] [Revised: 04/17/2014] [Accepted: 04/24/2014] [Indexed: 11/08/2022]
Abstract
Peritoneal membrane pathology limits long-term peritoneal dialysis (PD). Here, we tested whether JAK/STAT signaling is implicated and if its attenuation might be salutary. In cultured mesothelial cells, PD fluid activated, and the pan-JAK inhibitor P6 reduced, phospho-STAT1 and phospho-STAT3, periostin secretion, and cleaved caspase-3. Ex vivo, JAK was phosphorylated in PD effluent cells from long-term but not new PD patients. MCP-1 and periostin were increased in PD effluent in long term compared with new patients. In rats, twice daily, PD fluid infusion induced phospho-JAK, mesothelial cell hyperplasia, inflammation, fibrosis, and hypervascularity after 10 days of exposure to PD fluid. Concomitant instillation of a JAK1/2 inhibitor virtually completely attenuated these changes. Thus, our studies directly implicate JAK/STAT signaling in the mediation of peritoneal membrane pathology as a consequence of PD.
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30
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Herzog R, Bender TO, Vychytil A, Bialas K, Aufricht C, Kratochwill K. Dynamic O-linked N-acetylglucosamine modification of proteins affects stress responses and survival of mesothelial cells exposed to peritoneal dialysis fluids. J Am Soc Nephrol 2014; 25:2778-88. [PMID: 24854264 DOI: 10.1681/asn.2013101128] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
The ability of cells to respond and survive stressful conditions is determined, in part, by the attachment of O-linked N-acetylglucosamine (O-GlcNAc) to proteins (O-GlcNAcylation), a post-translational modification dependent on glucose and glutamine. This study investigates the role of dynamic O-GlcNAcylation of mesothelial cell proteins in cell survival during exposure to glucose-based peritoneal dialysis fluid (PDF). Immortalized human mesothelial cells and primary mesothelial cells, cultured from human omentum or clinical effluent of PD patients, were assessed for O-GlcNAcylation under normal conditions or after exposure to PDF. The dynamic status of O-GlcNAcylation and effects on cellular survival were investigated by chemical modulation with 6-diazo-5-oxo-L-norleucine (DON) to decrease or O-(2-acetamido-2-deoxy-D-glucopyranosylidene)amino N-phenyl carbamate (PUGNAc) to increase O-GlcNAc levels. Viability was decreased by reducing O-GlcNAc levels by DON, which also led to suppressed expression of the cytoprotective heat shock protein 72. In contrast, increasing O-GlcNAc levels by PUGNAc or alanyl-glutamine led to significantly improved cell survival paralleled by higher heat shock protein 72 levels during PDF treatment. Addition of alanyl-glutamine increased O-GlcNAcylation and partly counteracted its inhibition by DON, also leading to improved cell survival. Immunofluorescent analysis of clinical samples showed that the O-GlcNAc signal primarily originates from mesothelial cells. In conclusion, this study identified O-GlcNAcylation in mesothelial cells as a potentially important molecular mechanism after exposure to PDF. Modulating O-GlcNAc levels by clinically feasible interventions might evolve as a novel therapeutic target for the preservation of peritoneal membrane integrity in PD.
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Affiliation(s)
- Rebecca Herzog
- Department of Pediatrics and Adolescent Medicine and Zytoprotec GmbH, Vienna, Austria; and
| | - Thorsten O Bender
- Department of Nephrology and Medical Intensive Care, Charité University of Medicine Berlin, Berlin, Germany
| | - Andreas Vychytil
- Division of Nephrology and Dialysis, Department of Medicine III, Medical University of Vienna, Vienna, Austria
| | | | | | - Klaus Kratochwill
- Department of Pediatrics and Adolescent Medicine and Zytoprotec GmbH, Vienna, Austria; and
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Rusai K, Herzog R, Kuster L, Kratochwill K, Aufricht C. GSK-3β inhibition protects mesothelial cells during experimental peritoneal dialysis through upregulation of the heat shock response. Cell Stress Chaperones 2013; 18:569-79. [PMID: 23494401 PMCID: PMC3745257 DOI: 10.1007/s12192-013-0410-6] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2012] [Revised: 01/29/2013] [Accepted: 01/31/2013] [Indexed: 02/04/2023] Open
Abstract
Non-physiological components of peritoneal dialysis fluids (PDF) lead to the injury of peritoneal mesothelial cells resulting in the failure of peritoneal dialysis (PD) potentially via inadequate induction of the protective heat shock response (HSR). Glycogen synthase kinase-3β (GSK-3β) is a negative regulator of cell survival partly by suppression of the HSR and is influenced by stress stimuli also present in conventional PDF. The effects of PDF on GSK-3β activation and the impact of GSK-3β inhibition with lithium (LiCl) were investigated on cell survival with special regard to HSR, in particular to heat shock transcription factor 1 (HSF-1) activation and Hsp72 production in an in vitro model of PD using MeT-5A and primary mesothelial cells. Incubation of cells with the PDF Dianeal® (glucose-based, low pH, high glucose degradation products (GDP)) and Extraneal® (icodextrin-based, low pH, low GDP) caused activation of GSK-3β compared to the other tested PDF, i.e. Balance®, Physioneal® (normal pH, glucose-based, low GDP) and Nutrineal® (moderately acidic, amino acid-based). Inhibition of GSK-3β with LiCl in Dianeal® and Extraneal®-treated cells dose-dependently decreased cell damage and death rate and was paralleled by higher HSF-1 activation and Hsp72 expression. GSK-3β is activated by low pH GDP containing PDF with and without glucose as osmotic agent, indicating that GSK-3β is involved in mesothelial cell signalling in response to experimental PD. Inhibition of GSK-3β with LiCl ameliorated cell injury and improved HSR upon PDF exposure. Thus, GSK-3β inhibitors likely have therapeutic potential as cytoprotective additive for decreasing PDF toxicity.
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Affiliation(s)
- K. Rusai
- />Department of Pediatrics and Adolescent Medicine, Medical University of Vienna, Währinger Gürtel 18-20, 1090 Vienna, Austria
| | - R. Herzog
- />Zytoprotec GmbH, 1010 Vienna, Austria
| | - L. Kuster
- />Department of Pediatrics and Adolescent Medicine, Medical University of Vienna, Währinger Gürtel 18-20, 1090 Vienna, Austria
| | - K. Kratochwill
- />Department of Pediatrics and Adolescent Medicine, Medical University of Vienna, Währinger Gürtel 18-20, 1090 Vienna, Austria
- />Zytoprotec GmbH, 1010 Vienna, Austria
| | - C. Aufricht
- />Department of Pediatrics and Adolescent Medicine, Medical University of Vienna, Währinger Gürtel 18-20, 1090 Vienna, Austria
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A method to resolve the composition of heterogeneous affinity-purified protein complexes assembled around a common protein by chemical cross-linking, gel electrophoresis and mass spectrometry. Nat Protoc 2012; 8:75-97. [PMID: 23237831 DOI: 10.1038/nprot.2012.133] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Protein complexes form, dissociate and re-form in order to perform specific cellular functions. In this two-pronged protocol, noncovalent protein complexes are initially isolated by affinity purification for subsequent identification of the components by liquid chromatography high-resolution mass spectrometry (LC-MS) on a hybrid LTQ Orbitrap Velos. In the second prong of the approach, the affinity-purification strategy includes a chemical cross-linking step to 'freeze' a series of concurrently formed, heterogeneous protein subcomplex species that are visualized by gel electrophoresis. This branch of the methodology amalgamates standard and well-practiced laboratory methods to reveal compositional changes that occur in protein complex architecture. By using mouse N-terminally tagged streptavidin-binding peptide-hemagglutinin-TANK-binding kinase 1 (SH-TBK1), we chemically cross-linked the affinity-purified complex of SH-TBK1 with the homobifunctional lysine-specific reagent bis(sulfosuccinimidyl) suberate (BS(3)), and we separated the resultant protein complexes by denaturation and by silver-stained one- and two-dimensional SDS-PAGE. We observed a range of cross-linked TBK1 complexes of variable pI and M(r) and confirmed them by immunoblotting. LC-MS analysis of in situ-digested cross-linked proteins shows differences in the composition of the TBK1 subcomplexes. The protocol is inherently simple and can be readily extended to the investigation of a range of protein complexes. From cell lysis to data generation by LC-MS, the protocol takes approximately 2.5 to 5.5 d to perform.
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