51
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Charlton JR, Tan W, Daouk G, Teot L, Rosen S, Bennett KM, Cwiek A, Nam S, Emma F, Jouret F, Oliveira JP, Tranebjærg L, Frykholm C, Mane S, Hildebrandt F, Srivastava T, Storm T, Christensen EI, Nielsen R. Beyond the tubule: pathological variants of LRP2, encoding the megalin receptor, result in glomerular loss and early progressive chronic kidney disease. Am J Physiol Renal Physiol 2020; 319:F988-F999. [PMID: 33103447 DOI: 10.1152/ajprenal.00295.2020] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Pathogenic variants in the LRP2 gene, encoding the multiligand receptor megalin, cause a rare autosomal recessive syndrome: Donnai-Barrow/Facio-Oculo-Acoustico-Renal (DB/FOAR) syndrome. Because of the rarity of the syndrome, the long-term consequences of the tubulopathy on human renal health have been difficult to ascertain, and the human clinical condition has hitherto been characterized as a benign tubular condition with asymptomatic low-molecular-weight proteinuria. We investigated renal function and morphology in a murine model of DB/FOAR syndrome and in patients with DB/FOAR. We analyzed glomerular filtration rate in mice by FITC-inulin clearance and clinically characterized six families, including nine patients with DB/FOAR and nine family members. Urine samples from patients were analyzed by Western blot analysis and biopsy materials were analyzed by histology. In the mouse model, we used histological methods to assess nephrogenesis and postnatal renal structure and contrast-enhanced magnetic resonance imaging to assess glomerular number. In megalin-deficient mice, we found a lower glomerular filtration rate and an increase in the abundance of injury markers, such as kidney injury molecule-1 and N-acetyl-β-d-glucosaminidase. Renal injury was validated in patients, who presented with increased urinary kidney injury molecule-1, classical markers of chronic kidney disease, and glomerular proteinuria early in life. Megalin-deficient mice had normal nephrogenesis, but they had 19% fewer nephrons in early adulthood and an increased fraction of nephrons with disconnected glomerulotubular junction. In conclusion, megalin dysfunction, as present in DB/FOAR syndrome, confers an increased risk of progression into chronic kidney disease.
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Affiliation(s)
- Jennifer R Charlton
- Division of Nephrology, Department of Pediatrics, University of Virginia, Charlottesville, Virginia
| | - Weizhen Tan
- Division of Nephrology, Massachusetts General Hospital for Children, Boston, Massachusetts
| | - Ghaleb Daouk
- Division of Nephrology, Massachusetts General Hospital for Children, Boston, Massachusetts
| | - Lisa Teot
- Department of Pathology, Boston Children's Hospital, Boston, Massachusetts
| | - Seymour Rosen
- Department of Pathology, Boston Children's Hospital, Boston, Massachusetts.,Department of Pathology, Beth Israel Deaconess Medical Center, Boston, Massachusetts
| | - Kevin M Bennett
- Department of Radiology, Washington University in Saint Louis, St. Louis, Missouri
| | - Aleksandra Cwiek
- Division of Nephrology, Department of Pediatrics, University of Virginia, Charlottesville, Virginia
| | - Sejin Nam
- Department of Physics, University of Hawai'i at Manoa, Manoa, Hawai'i
| | - Francesco Emma
- Division of Nephrology, Department of Pediatric Subspecialties, Bambino Gesù Children's Hospital- Istituto di Ricovero e Cura a Carattere Scientifico, Rome, Italy
| | - François Jouret
- Groupe Interdisciplinaire de Génoprotéomique Appliquée, Unit of Cardiovascular Sciences, University of Liège, Liège, Belgium
| | - João Paulo Oliveira
- Service of Medical Genetics, São João University Hospital Centre and Faculty of Medicine, University of Porto and i3S-Institute for Health Research and Innovation, Porto, Portugal
| | - Lisbeth Tranebjærg
- Department of Clinical Genetics, Rigshospitalet/The Kennedy Centre, Copenhagen, Denmark.,Institute of Clinical Medicine, University of Copenhagen, The Panum Institute, Copenhagen, Denmark
| | - Carina Frykholm
- Department of Immunology, Genetics and Pathology, Uppsala University, Uppsala, Sweden
| | - Shrikant Mane
- Department of Genetics, Yale University School of Medicine, New Haven, Connecticut
| | - Friedhelm Hildebrandt
- Department of Medicine, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts
| | | | - Tina Storm
- Department of Biomedicine, Aarhus University, Aarhus, Denmark
| | | | - Rikke Nielsen
- Department of Biomedicine, Aarhus University, Aarhus, Denmark
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52
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Jakovac H, Stašić N, Krašević M, Jonjić N, Radošević-Stašić B. Expression profiles of metallothionein-I/II and megalin/LRP-2 in uterine cervical squamous lesions. Virchows Arch 2020; 478:735-746. [PMID: 33084977 PMCID: PMC7990851 DOI: 10.1007/s00428-020-02947-w] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2020] [Revised: 09/18/2020] [Accepted: 10/09/2020] [Indexed: 12/29/2022]
Abstract
Metallothioneins (MTs) are phylogenetically old cysteine-rich proteins, which are implicated in a variety of physiological and pathological processes. Their growth-regulating, anti-apoptotic and anti-inflammatory functions have been attributed not only to intracellular free radical scavenging and to zinc and copper regulation but also to the ability of secreted MT to bind on surface lipoprotein receptor-megalin/LRP2, which enables the endocytosis of MT-I/II and a wide range of other functionally distinct ligands. In the present study, we analysed the expression pattern of both proteins in 55 cases of premalignant transformation of cervical squamous cells, i.e. in low- and high-grade squamous intraepithelial lesion (LSIL and HSIL). The data showed that in LSIL (cervical intraepithelial neoplasia CIN1; N = 25) MTs were present only in basal and parabasal cells and that megalin was only weakly expressed. In HSIL (CIN2; N = 15 and CIN 3/carcinoma in situ; N = 15), however, overexpression and co-localization of MT with megalin were found in the entire hyperplastic epithelium. Moreover, megalin immunoreactivity appeared on the glandular epithelium and vascular endothelium, as well as on lymphatic cells in stroma. Besides, multiple megalin-positive cells expressed phosphorylated Akt1, implying that MT- and/or megalin-dependent prosurvival signal transduction pathways might contribute to the development of severe cervical dysplasia. The data emphasize the diagnostic power of combined MT/megalin analysis in pre-cancer screening.
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Affiliation(s)
- Hrvoje Jakovac
- Department of Physiology and Immunology, Medical Faculty, University of Rijeka, B. Branchetta 20, 51 000 Rijeka, Croatia
| | - Nikola Stašić
- Teaching Institute of Public Health, Primorsko-goranska County, Medical Faculty, University of Rijeka, Rijeka, Croatia
| | - Maja Krašević
- Department of Pathology, Medical Faculty, University of Rijeka, Rijeka, Croatia
| | - Nives Jonjić
- Department of Pathology, Medical Faculty, University of Rijeka, Rijeka, Croatia
| | - Biserka Radošević-Stašić
- Department of Physiology and Immunology, Medical Faculty, University of Rijeka, B. Branchetta 20, 51 000 Rijeka, Croatia
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53
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Gomes JR, Lobo A, Nogueira R, Terceiro AF, Costelha S, Lopes IM, Magalhães A, Summavielle T, Saraiva MJ. Neuronal megalin mediates synaptic plasticity-a novel mechanism underlying intellectual disabilities in megalin gene pathologies. Brain Commun 2020; 2:fcaa135. [PMID: 33225275 PMCID: PMC7667529 DOI: 10.1093/braincomms/fcaa135] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2020] [Revised: 07/14/2020] [Accepted: 07/16/2020] [Indexed: 12/15/2022] Open
Abstract
Donnai-Barrow syndrome, a genetic disorder associated to LRP2 (low-density lipoprotein receptor 2/megalin) mutations, is characterized by unexplained neurological symptoms and intellectual deficits. Megalin is a multifunctional endocytic clearance cell-surface receptor, mostly described in epithelial cells. This receptor is also expressed in the CNS, mainly in neurons, being involved in neurite outgrowth and neuroprotective mechanisms. Yet, the mechanisms involved in the regulation of megalin in the CNS are poorly understood. Using transthyretin knockout mice, a megalin ligand, we found that transthyretin positively regulates neuronal megalin levels in different CNS areas, particularly in the hippocampus. Transthyretin is even able to rescue megalin downregulation in transthyretin knockout hippocampal neuronal cultures, in a positive feedback mechanism via megalin. Importantly, transthyretin activates a regulated intracellular proteolysis mechanism of neuronal megalin, producing an intracellular domain, which is translocated to the nucleus, unveiling megalin C-terminal as a potential transcription factor, able to regulate gene expression. We unveil that neuronal megalin reduction affects physiological neuronal activity, leading to decreased neurite number, length and branching, and increasing neuronal susceptibility to a toxic insult. Finally, we unravel a new unexpected role of megalin in synaptic plasticity, by promoting the formation and maturation of dendritic spines, and contributing for the establishment of active synapses, both in in vitro and in vivo hippocampal neurons. Moreover, these structural and synaptic roles of megalin impact on learning and memory mechanisms, since megalin heterozygous mice show hippocampal-related memory and learning deficits in several behaviour tests. Altogether, we unveil a complete novel role of megalin in the physiological neuronal activity, mainly in synaptic plasticity with impact in learning and memory. Importantly, we contribute to disclose the molecular mechanisms underlying the cognitive and intellectual disabilities related to megalin gene pathologies.
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Affiliation(s)
- João R Gomes
- Molecular Neurobiology Unit, IBMC- Instituto de Biologia Molecular e Celular, 4200-135 Porto, Portugal.,I3S-Instituto de Investigação e Inovação em Saúde, Universidade do Porto, 4200-135 Porto, Portugal
| | - Andrea Lobo
- I3S-Instituto de Investigação e Inovação em Saúde, Universidade do Porto, 4200-135 Porto, Portugal.,Addiction Biology Group, IBMC- Instituto de Biologia Molecular e Celular, 4200-135 Porto, Portugal
| | - Renata Nogueira
- Molecular Neurobiology Unit, IBMC- Instituto de Biologia Molecular e Celular, 4200-135 Porto, Portugal.,I3S-Instituto de Investigação e Inovação em Saúde, Universidade do Porto, 4200-135 Porto, Portugal
| | - Ana F Terceiro
- I3S-Instituto de Investigação e Inovação em Saúde, Universidade do Porto, 4200-135 Porto, Portugal.,Addiction Biology Group, IBMC- Instituto de Biologia Molecular e Celular, 4200-135 Porto, Portugal
| | - Susete Costelha
- Molecular Neurobiology Unit, IBMC- Instituto de Biologia Molecular e Celular, 4200-135 Porto, Portugal.,I3S-Instituto de Investigação e Inovação em Saúde, Universidade do Porto, 4200-135 Porto, Portugal
| | - Igor M Lopes
- I3S-Instituto de Investigação e Inovação em Saúde, Universidade do Porto, 4200-135 Porto, Portugal.,Addiction Biology Group, IBMC- Instituto de Biologia Molecular e Celular, 4200-135 Porto, Portugal
| | - Ana Magalhães
- I3S-Instituto de Investigação e Inovação em Saúde, Universidade do Porto, 4200-135 Porto, Portugal.,Addiction Biology Group, IBMC- Instituto de Biologia Molecular e Celular, 4200-135 Porto, Portugal
| | - Teresa Summavielle
- I3S-Instituto de Investigação e Inovação em Saúde, Universidade do Porto, 4200-135 Porto, Portugal.,Addiction Biology Group, IBMC- Instituto de Biologia Molecular e Celular, 4200-135 Porto, Portugal
| | - Maria J Saraiva
- Molecular Neurobiology Unit, IBMC- Instituto de Biologia Molecular e Celular, 4200-135 Porto, Portugal.,I3S-Instituto de Investigação e Inovação em Saúde, Universidade do Porto, 4200-135 Porto, Portugal
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54
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Bellucci MC, Volonterio A. Aminoglycosides: From Antibiotics to Building Blocks for the Synthesis and Development of Gene Delivery Vehicles. Antibiotics (Basel) 2020; 9:E504. [PMID: 32796727 PMCID: PMC7459817 DOI: 10.3390/antibiotics9080504] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Revised: 07/29/2020] [Accepted: 08/07/2020] [Indexed: 02/06/2023] Open
Abstract
Aminoglycosides are a class of naturally occurring and semi synthetic antibiotics that have been used for a long time in fighting bacterial infections. Due to acquired antibiotic resistance and inherent toxicity, aminoglycosides have experienced a decrease in interest over time. However, in the last decade, we are seeing a renaissance of aminoglycosides thanks to a better understanding of their chemistry and mode of action, which had led to new trends of application. The purpose of this comprehensive review is to highlight one of these new fields of application: the use of aminoglycosides as building blocks for the development of liposomal and polymeric vectors for gene delivery. The design, synthetic strategies, ability to condensate the genetic material, the efficiency in transfection, and cytotoxicity as well as when available, the antibacterial activity of aminoglycoside-based cationic lipids and polymers are covered and critically analyzed.
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Affiliation(s)
- Maria Cristina Bellucci
- Department of Food, Environmental and Nutritional Sciences, Università degli Studi di Milano, via Celoria 2, 20133 Milano, Italy;
| | - Alessandro Volonterio
- Department of Chemistry, Material and Chemical Engineer “Giulio Natta”, Politecnico di Milano, via Mancinelli 7, 20131 Milano, Italy
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55
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Marable SS, Chung E, Park JS. Hnf4a Is Required for the Development of Cdh6-Expressing Progenitors into Proximal Tubules in the Mouse Kidney. J Am Soc Nephrol 2020; 31:2543-2558. [PMID: 32764140 DOI: 10.1681/asn.2020020184] [Citation(s) in RCA: 38] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2020] [Accepted: 07/06/2020] [Indexed: 01/03/2023] Open
Abstract
BACKGROUND Hepatocyte NF 4α (Hnf4a) is a major regulator of renal proximal tubule (PT) development. In humans, a mutation in HNF4A impairs PT functions and is associated with Fanconi renotubular syndrome (FRTS). In mice, mosaic deletion of Hnf4a in the developing kidney reduces the population of PT cells, leading to FRTS-like symptoms. The molecular mechanisms underlying the role of Hnf4a in PT development remain unclear. METHODS The gene deletion tool Osr2Cre removed Hnf4a in developing nephrons in mice, generating a novel model for FRTS. Immunofluorescence analysis characterized the mutant phenotype, and lineage analysis tested whether Cadherin-6 (Cdh6)-expressing cells are PT progenitors. Genome-wide mapping of Hnf4a binding sites and differential gene analysis of Hnf4a mutant kidneys identified direct target genes of Hnf4a. RESULTS Deletion of Hnf4a with Osr2Cre led to the complete loss of mature PT cells, lethal to the Hnf4a mutant mice. Cdh6high, lotus tetragonolobus lectin-low (LTLlow) cells serve as PT progenitors and demonstrate higher proliferation than Cdh6low, LTLhigh differentiated PT cells. Additionally, Hnf4a is required for PT progenitors to differentiate into mature PT cells. Genomic analyses revealed that Hnf4a directly regulates the expression of genes involved in transmembrane transport and metabolism. CONCLUSIONS Hnf4a promotes the differentiation of PT progenitors into mature PT cells by regulating the expression of genes associated with reabsorption, the major function of PT cells.
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Affiliation(s)
- Sierra S Marable
- Division of Pediatric Urology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio.,Division of Developmental Biology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio
| | - Eunah Chung
- Division of Pediatric Urology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio.,Division of Developmental Biology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio
| | - Joo-Seop Park
- Division of Pediatric Urology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio .,Division of Developmental Biology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio.,Department of Surgery, University of Cincinnati College of Medicine, Cincinnati, Ohio
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56
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Kim CS, Mathew AP, Uthaman S, Moon MJ, Bae EH, Kim SW, Park IK. Glycol chitosan-based renal docking biopolymeric nanomicelles for site-specific delivery of the immunosuppressant. Carbohydr Polym 2020; 241:116255. [DOI: 10.1016/j.carbpol.2020.116255] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2019] [Revised: 03/25/2020] [Accepted: 04/02/2020] [Indexed: 01/26/2023]
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57
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Bryniarski MA, Yee BM, Chaves LD, Stahura CM, Yacoub R, Morris ME. Megalin-mediated albumin endocytosis in cultured murine mesangial cells. Biochem Biophys Res Commun 2020; 529:740-746. [PMID: 32736701 DOI: 10.1016/j.bbrc.2020.05.166] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2020] [Accepted: 05/22/2020] [Indexed: 12/25/2022]
Abstract
Endocytosis by podocytes is gaining increased attention as a biologic means of removing large proteins such as serum albumin from the glomerular barrier. Some of this function has been attributed to the megalin/cubilin (Lrp2/Cubn) receptor complex and the albumin recycling protein FcRn (Fcgrt). However, whether other glomerular cells possess the potential to perform this same phenomenon or express these proteins remains uncharacterized. Mesangial cells are uniquely positioned in glomeruli and represent a cell type capable of performing several diverse functions. Here, the expression of megalin and FcRn in murine mesangial cells along with the megalin adaptor protein Dab-2 (Dab2) was shown for the first time. Cubilin mRNA expression was detected, but the absence of the cubilin partner amnionless (Amn) suggested that cubilin is minimally functional, if at all, in these cells. Mesangial cell endocytosis of albumin was characterized and shown to involve a receptor-mediated process. Albumin endocytosis was significantly impaired (p < 0.01) under inducible megalin knockdown conditions in stably transduced mesangial cells. The current work provides both the novel identification of megalin and FcRn in mesangial cells and the functional demonstration of megalin-mediated albumin endocytosis.
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Affiliation(s)
- Mark A Bryniarski
- Department of Pharmaceutical Sciences, School of Pharmacy and Pharmaceutical Sciences, University at Buffalo, 303 Pharmacy Building, Buffalo, NY, 14214, USA
| | - Benjamin M Yee
- Department of Pharmaceutical Sciences, School of Pharmacy and Pharmaceutical Sciences, University at Buffalo, 303 Pharmacy Building, Buffalo, NY, 14214, USA
| | - Lee D Chaves
- Department of Internal Medicine, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, 875 Ellicott St, Buffalo, NY, 14214, USA
| | - Corrine M Stahura
- Department of Internal Medicine, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, 875 Ellicott St, Buffalo, NY, 14214, USA
| | - Rabi Yacoub
- Department of Internal Medicine, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, 875 Ellicott St, Buffalo, NY, 14214, USA
| | - Marilyn E Morris
- Department of Pharmaceutical Sciences, School of Pharmacy and Pharmaceutical Sciences, University at Buffalo, 303 Pharmacy Building, Buffalo, NY, 14214, USA.
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58
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Joyce KE, Delamere J, Bradwell S, Myers SD, Ashdown K, Rue C, Lucas SJ, Thomas OD, Fountain A, Edsell M, Myers F, Malein W, Imray C, Clarke A, Lewis CT, Newman C, Johnson B, Cadigan P, Wright A, Bradwell A. Hypoxia is not the primary mechanism contributing to exercise-induced proteinuria. BMJ Open Sport Exerc Med 2020; 6:e000662. [PMID: 32341794 PMCID: PMC7173992 DOI: 10.1136/bmjsem-2019-000662] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/23/2020] [Indexed: 11/28/2022] Open
Abstract
Introduction Proteinuria increases at altitude and with exercise, potentially as a result of hypoxia. Using urinary alpha-1 acid glycoprotein (α1-AGP) levels as a sensitive marker of proteinuria, we examined the impact of relative hypoxia due to high altitude and blood pressure-lowering medication on post-exercise proteinuria. Methods Twenty individuals were pair-matched for sex, age and ACE genotype. They completed maximal exercise tests once at sea level and twice at altitude (5035 m). Losartan (100 mg/day; angiotensin-receptor blocker) and placebo were randomly assigned within each pair 21 days before ascent. The first altitude exercise test was completed within 24–48 hours of arrival (each pair within ~1 hour). Acetazolamide (125 mg two times per day) was administrated immediately after this test for 48 hours until the second altitude exercise test. Results With placebo, post-exercise α1-AGP levels were similar at sea level and altitude. Odds ratio (OR) for increased resting α1-AGP at altitude versus sea level was greater without losartan (2.16 times greater). At altitude, OR for reduced post-exercise α1-AGP (58% lower) was higher with losartan than placebo (2.25 times greater, p=0.059) despite similar pulse oximetry (SpO2) (p=0.95) between groups. Acetazolamide reduced post-exercise proteinuria by approximately threefold (9.3±9.7 vs 3.6±6.0 μg/min; p=0.025) although changes were not correlated (r=−0.10) with significant improvements in SpO2 (69.1%±4.5% vs 75.8%±3.8%; p=0.001). Discussion Profound systemic hypoxia imposed by altitude does not result in greater post-exercise proteinuria than sea level. Losartan and acetazolamide may attenuate post-exercise proteinuria, however further research is warranted.
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Affiliation(s)
- Kelsley E Joyce
- School of Sport, Exercise, and Rehabilitation Sciences, University of Birmingham, Birmingham, UK.,Birmingham Medical Research Expeditionary Society, University of Birmingham, Birmingham, UK
| | - John Delamere
- Birmingham Medical Research Expeditionary Society, University of Birmingham, Birmingham, UK.,Institute of Clinical Sciences, University of Birmingham, Birmingham, UK
| | - Susie Bradwell
- Birmingham Medical Research Expeditionary Society, University of Birmingham, Birmingham, UK.,Medical School, East Surrey Hospital, Redhill, Surrey, UK
| | - Stephen David Myers
- Birmingham Medical Research Expeditionary Society, University of Birmingham, Birmingham, UK.,Occupational Performance Research Group, University of Chichester Department of Sport and Exercise Sciences, Chichester, West Sussex, UK
| | - Kimberly Ashdown
- Birmingham Medical Research Expeditionary Society, University of Birmingham, Birmingham, UK.,Occupational Performance Research Group, University of Chichester Department of Sport and Exercise Sciences, Chichester, West Sussex, UK
| | - Carla Rue
- Birmingham Medical Research Expeditionary Society, University of Birmingham, Birmingham, UK.,Occupational Performance Research Group, University of Chichester Department of Sport and Exercise Sciences, Chichester, West Sussex, UK
| | - Samuel Je Lucas
- School of Sport, Exercise, and Rehabilitation Sciences, University of Birmingham, Birmingham, UK.,Birmingham Medical Research Expeditionary Society, University of Birmingham, Birmingham, UK
| | - Owen D Thomas
- Birmingham Medical Research Expeditionary Society, University of Birmingham, Birmingham, UK.,Institute of Clinical Sciences, University of Birmingham, Birmingham, UK
| | - Amy Fountain
- Research & Development, Binding Site Group Ltd, Edgbaston, Birmingham, UK
| | - Mark Edsell
- Birmingham Medical Research Expeditionary Society, University of Birmingham, Birmingham, UK.,St. George's University Hospital, University of London, London, UK
| | - Fiona Myers
- School of Biological Sciences, University of Portsmouth, Portsmouth, UK
| | - Will Malein
- Birmingham Medical Research Expeditionary Society, University of Birmingham, Birmingham, UK.,Department of Anaesthesia, Ninewells Hospital, Dundee, UK
| | - Chris Imray
- Birmingham Medical Research Expeditionary Society, University of Birmingham, Birmingham, UK.,Vascular Surgery, University Hospitals Coventry and Warwickshire NHS Trust, Coventry, UK
| | - Alex Clarke
- Birmingham Medical Research Expeditionary Society, University of Birmingham, Birmingham, UK.,Department of Bioengineering, Imperial College London, London, UK
| | - Chrisopher T Lewis
- Birmingham Medical Research Expeditionary Society, University of Birmingham, Birmingham, UK.,Academic Foundation Programme, NHS Highland, Inverness, United Kingdom
| | - Charles Newman
- Birmingham Medical Research Expeditionary Society, University of Birmingham, Birmingham, UK.,University Hospitals Birmingham NHS Foundation Trust, Birmingham, UK
| | - Brian Johnson
- Birmingham Medical Research Expeditionary Society, University of Birmingham, Birmingham, UK.,BASEM, Doncaster, UK
| | - Patrick Cadigan
- Birmingham Medical Research Expeditionary Society, University of Birmingham, Birmingham, UK
| | - Alexander Wright
- Birmingham Medical Research Expeditionary Society, University of Birmingham, Birmingham, UK.,Medical School, University of Birmingham, Birmingham, UK
| | - Arthur Bradwell
- Birmingham Medical Research Expeditionary Society, University of Birmingham, Birmingham, UK.,Institute of Clinical Sciences, University of Birmingham, Birmingham, UK
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Ren Q, Weyer K, Rbaibi Y, Long KR, Tan RJ, Nielsen R, Christensen EI, Baty CJ, Kashlan OB, Weisz OA. Distinct functions of megalin and cubilin receptors in recovery of normal and nephrotic levels of filtered albumin. Am J Physiol Renal Physiol 2020; 318:F1284-F1294. [PMID: 32200668 DOI: 10.1152/ajprenal.00030.2020] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Proximal tubule (PT) cells express a single saturable albumin-binding site whose affinity matches the estimated tubular concentration of albumin; however, albumin uptake capacity is greatly increased under nephrotic conditions. Deciphering the individual contributions of megalin and cubilin to the uptake of normal and nephrotic levels of albumin is impossible in vivo, as knockout of megalin in mice globally disrupts PT endocytic uptake. We quantified concentration-dependent albumin uptake in an optimized opossum kidney cell culture model and fit the kinetic profiles to identify albumin-binding affinities and uptake capacities. Mathematical deconvolution fit best to a three-component model that included saturable high- and low-affinity uptake sites for albumin and underlying nonsaturable uptake consistent with passive uptake of albumin in the fluid phase. Knockdown of cubilin or its chaperone amnionless selectively reduced the binding capacity of the high-affinity site, whereas knockdown of megalin impacted the low-affinity site. Knockdown of disabled-2 decreased the capacities of both binding sites. Additionally, knockdown of megalin or disabled-2 profoundly inhibited the uptake of a fluid phase marker, with cubilin knockdown having a more modest effect. We propose a novel model for albumin retrieval along the PT in which cubilin and megalin receptors have different functions in recovering filtered albumin in proximal tubule cells. Cubilin binding to albumin is tuned to capture normally filtered levels of the protein. In contrast, megalin binding to albumin is of lower affinity, and its expression is also essential for enabling the recovery of high concentrations of albumin in the fluid phase.
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Affiliation(s)
- Qidong Ren
- School of Medicine, Tsinghua University, Beijing, China.,Renal-Electrolyte Division, Department of Medicine, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
| | - Kathrin Weyer
- Department of Biomedicine, Aarhus University, Aarhus, Denmark
| | - Youssef Rbaibi
- Renal-Electrolyte Division, Department of Medicine, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
| | - Kimberly R Long
- Renal-Electrolyte Division, Department of Medicine, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
| | - Roderick J Tan
- Renal-Electrolyte Division, Department of Medicine, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
| | - Rikke Nielsen
- Department of Biomedicine, Aarhus University, Aarhus, Denmark
| | | | - Catherine J Baty
- Renal-Electrolyte Division, Department of Medicine, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
| | - Ossama B Kashlan
- Renal-Electrolyte Division, Department of Medicine, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
| | - Ora A Weisz
- Renal-Electrolyte Division, Department of Medicine, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
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Protective Role of Vitamin D in Renal Tubulopathies. Metabolites 2020; 10:metabo10030115. [PMID: 32204545 PMCID: PMC7142711 DOI: 10.3390/metabo10030115] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2020] [Revised: 03/13/2020] [Accepted: 03/17/2020] [Indexed: 02/06/2023] Open
Abstract
Vitamin D is tightly linked with renal tubular homeostasis: the mitochondria of proximal convoluted tubule cells are the production site of 1α,25-dihydroxyvitamin D3. Patients with renal impairment or tubular injury often suffer from chronic inflammation. This alteration comes from oxidative stress, acidosis, decreased clearance of inflammatory cytokines and stimulation of inflammatory factors. The challenge is to find the right formula for each patient to correctly modulate the landscape of treatment and preserve the essential functions of the organism without perturbating its homeostasis. The complexity of the counter-regulation mechanisms and the different axis involved in the Vitamin D equilibrium pose a major issue on Vitamin D as a potential effective anti-inflammatory drug. The therapeutic use of this compound should be able to inhibit the development of inflammation without interfering with normal homeostasis. Megalin-Cubilin-Amnionless and the FGF23-Klotho axis represent two Vitamin D-linked mechanisms that could modulate and ameliorate the damage response at the renal tubular level, balancing Vitamin D therapy with an effect potent enough to contrast the inflammatory cascades, but which avoids potential severe side effects.
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Oroojalian F, Charbgoo F, Hashemi M, Amani A, Yazdian-Robati R, Mokhtarzadeh A, Ramezani M, Hamblin MR. Recent advances in nanotechnology-based drug delivery systems for the kidney. J Control Release 2020; 321:442-462. [PMID: 32067996 DOI: 10.1016/j.jconrel.2020.02.027] [Citation(s) in RCA: 89] [Impact Index Per Article: 22.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2020] [Revised: 02/12/2020] [Accepted: 02/13/2020] [Indexed: 12/24/2022]
Abstract
The application of nanotechnology in medicine has the potential to make a great impact on human health, ranging from prevention to diagnosis and treatment of disease. The kidneys are the main organ of the human urinary system, responsible for filtering the blood, and concentrating metabolic waste into urine by means of the renal glomerulus. The glomerular filtration apparatus presents a barrier against therapeutic agents based on charge and/or molecular size. Therefore, drug delivery to the kidneys faces significant difficulties resulting in treatment failure in several renal disorders. Accordingly, different strategies have recently being explored for enhancing the delivery of therapeutic agents across the filtration barrier of the glomerulus. Nanosystems with different physicochemical properties, including size, shape, surface, charge, and possessing biological features such as high cellular internalization, low cytotoxicity, controllable pharmacokinetics and biodistribution, have shown promising results for renal therapy. Different types of nanoparticles (NPs) have been used to deliver drugs to the kidney. In this review, we discuss nanotechnology-based drug delivery approaches for acute kidney injury, chronic kidney disease, renal fibrosis, renovascular hypertension and kidney cancer.
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Affiliation(s)
- Fatemeh Oroojalian
- Department of Advanced Sciences and Technologies, North Khorasan University of Medical Sciences, Bojnurd, Iran
| | - Fahimeh Charbgoo
- DWI - Leibniz Institute for Interactive Materials, Forckenbeckstr. 50, 52056 Aachen, Germany
| | - Maryam Hashemi
- Nanotechnology Research Center, Pharmaceutical Technology Institute, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Amir Amani
- Department of Advanced Sciences and Technologies, North Khorasan University of Medical Sciences, Bojnurd, Iran; Department of Medical Nanotechnology, School of Advanced Technologies in Medicine, Tehran University of Medical Sciences, Tehran, Iran
| | - Rezvan Yazdian-Robati
- Molecular and Cell Biology Research Center, Faculty of Medicine, Mazandaran University of Medical Sciences, Sari, Iran
| | - Ahad Mokhtarzadeh
- Immunology Research Center, Tabriz University of Medical Sciences, Tabriz, Iran.
| | - Mohammad Ramezani
- Department of Pharmaceutical Biotechnology, School of Pharmacy, Mashhad University of Medical Sciences, Mashhad, Iran.
| | - Michael R Hamblin
- Wellman Center for Photomedicine, Massachusetts General Hospital, Boston, MA 02114, USA; Department of Dermatology, Harvard Medical School, Boston, MA 02115, USA; Laser Research Centre, Faculty of Health Science, University of Johannesburg, Doornfontein 2028, South Africa.
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62
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Sawada A, Kawanishi K, Horita S, Omoto K, Okumi M, Shimizu T, Taneda S, Fuchinoue S, Ishida H, Honda K, Hattori M, Tanabe K, Koike J, Nagashima Y, Nitta K. Monoclonal immunoglobulin G deposits on tubular basement membrane in renal allograft: is this significant for chronic allograft injury? Nephrol Dial Transplant 2020; 34:711-717. [PMID: 30124906 PMCID: PMC6452215 DOI: 10.1093/ndt/gfy256] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2017] [Indexed: 12/24/2022] Open
Abstract
Background Tubular basement membrane immune deposits (TBMID) has rarely been observed in renal allografts. It is usually found in BK virus nephropathy and immune complex glomerulonephritis; however, its significance is not well understood. We conducted a retrospective clinicopathological study on monoclonal immunoglobulin G (IgG) TBMID. Methods We studied 7177 renal allograft biopsy specimens obtained from Tokyo Women’s Medical University from 2007 to 2015 and performed light microscopic, electron microscopic and immunofluorescence studies. Results Tubular basement membrane (TBM) deposits of IgG were found in 73 biopsies from 61 patients and the IgG subclass was obtained in 31 biopsies. There were no cases of monoclonal IgA or IgM TBMID. In total, 13 biopsies from 10 patients showed monoclonal IgG TBMID. Of these, seven showed monoclonal IgG1κ TBMID and one each showed monoclonal IgG2κ, IgG2λ and IgG3κ TBMID. Conversely, eight patients showed polyclonal IgG TBMID. In electron microscopy, large granular electron-dense deposits (EDDs) in the TBM were detected in all patients with monoclonal IgG1κ TBMID. EDDs were absent in TBM in patients with monoclonal IgG2κ, IgG2λ or IgG3κ TBMID. Progression of interstitial fibrosis and tubular atrophy (IFTA) was significantly higher in patients with monoclonal IgG1κ TBMID than in those with polyclonal IgG TBMID (P < 0.05). There were no significant differences in the other clinical parameters between monoclonal IgG1κ and polyclonal IgG TBMID. Conclusions This is the first study of patients with monoclonal IgG TBMID in renal allografts. We found that monoclonal IgG1κ TBMID was associated with EDD formation in TBM and IFTA progression.
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Affiliation(s)
- Anri Sawada
- Department of Surgical Pathology, Tokyo Women's Medical University, Tokyo, Japan.,Department of Medicine, Kidney Center, Tokyo Women's Medical University, Tokyo, Japan
| | - Kunio Kawanishi
- Department of Surgical Pathology, Tokyo Women's Medical University, Tokyo, Japan
| | - Shigeru Horita
- Division of Pathology, Kidney Center, Tokyo Women's Medical University, Tokyo, Japan
| | - Kazuya Omoto
- Department of Transplant Surgery, Kidney Center, Toda Chuo General Hospital, Saitama, Japan
| | - Masayoshi Okumi
- Department of Urology, Kidney Center, Tokyo Women's Medical University, Tokyo, Japan
| | - Tomokazu Shimizu
- Department of Transplant Surgery, Kidney Center, Toda Chuo General Hospital, Saitama, Japan
| | - Sekiko Taneda
- Department of Surgical Pathology, Tokyo Women's Medical University, Tokyo, Japan
| | - Shohei Fuchinoue
- Department of Surgery, Kidney Center, Tokyo Women's Medical University, Tokyo, Japan
| | - Hideki Ishida
- Department of Urology, Kidney Center, Tokyo Women's Medical University, Tokyo, Japan
| | - Kazuho Honda
- Department of Anatomy, Showa University School of Medicine, Tokyo, Japan
| | - Motoshi Hattori
- Department of Pediatric Nephrology, Kidney Center, Tokyo Women's Medical University, Tokyo, Japan
| | - Kazunari Tanabe
- Department of Urology, Kidney Center, Tokyo Women's Medical University, Tokyo, Japan
| | - Junki Koike
- Department of Pathology, Kawasaki Municipal Tama Hospital, Kawasaki, Kanagawa, Japan
| | - Yoji Nagashima
- Department of Surgical Pathology, Tokyo Women's Medical University, Tokyo, Japan
| | - Kosaku Nitta
- Department of Medicine, Kidney Center, Tokyo Women's Medical University, Tokyo, Japan
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63
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Chen Z, Luciani A, Mateos JM, Barmettler G, Giles RH, Neuhauss SCF, Devuyst O. Transgenic zebrafish modeling low-molecular-weight proteinuria and lysosomal storage diseases. Kidney Int 2019; 97:1150-1163. [PMID: 32061435 DOI: 10.1016/j.kint.2019.11.016] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2019] [Revised: 10/16/2019] [Accepted: 11/01/2019] [Indexed: 12/12/2022]
Abstract
Epithelial cells lining the proximal tubule of the kidney reabsorb and metabolize most of the filtered low-molecular-weight proteins through receptor-mediated endocytosis and lysosomal processing. Congenital and acquired dysfunctions of the proximal tubule are consistently reflected by the inappropriate loss of solutes including low-molecular-weight proteins in the urine. The zebrafish pronephros shares individual functional segments with the human nephron, including lrp2a/megalin-dependent endocytic transport processes of the proximal tubule. Although the zebrafish has been used as a model organism for toxicological studies and drug discovery, there is no available assay that allows large-scale assessment of proximal tubule function in larval or adult stages. Here we establish a transgenic Tg(lfabp::½vdbp-mCherry) zebrafish line expressing in the liver the N-terminal region of vitamin D-binding protein coupled to the acid-insensitive, red monomeric fluorescent protein mCherry (½vdbp-mCherry). This low-molecular-weight protein construct is secreted into the bloodstream, filtered through the glomerulus, reabsorbed by receptor-mediated endocytosis and processed in the lysosomes of proximal tubule cells of the fish. Thus, our proof-of-concept studies using zebrafish larvae knockout for lrp2a and clcn7 or exposed to known nephrotoxins (gentamicin and cisplatin) demonstrate that this transgenic line is useful to monitor low-molecular-weight proteinuria and lysosomal processing. This represents a powerful new model organism for drug screening and studies of nephrotoxicity.
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Affiliation(s)
- Zhiyong Chen
- Institute of Physiology, University of Zurich, Zurich, Switzerland
| | | | - José María Mateos
- Center for Microscopy and Image Analysis, University of Zurich, Zurich, Switzerland
| | - Gery Barmettler
- Center for Microscopy and Image Analysis, University of Zurich, Zurich, Switzerland
| | - Rachel H Giles
- Department of Nephrology and Hypertension, Hubrecht Institute, Utrecht, The Netherlands; University Medical Center Utrecht, Utrecht, The Netherlands
| | | | - Olivier Devuyst
- Institute of Physiology, University of Zurich, Zurich, Switzerland.
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Olsen CE, Cheung LH, Weyergang A, Berg K, Vallera DA, Rosenblum MG, Selbo PK. Design, Characterization, and Evaluation of scFvCD133/rGelonin: A CD133-Targeting Recombinant Immunotoxin for Use in Combination with Photochemical Internalization. J Clin Med 2019; 9:jcm9010068. [PMID: 31888091 PMCID: PMC7019722 DOI: 10.3390/jcm9010068] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2019] [Revised: 12/17/2019] [Accepted: 12/22/2019] [Indexed: 01/02/2023] Open
Abstract
The objective of this study was to develop and explore a novel CD133-targeting immunotoxin (IT) for use in combination with the endosomal escape method photochemical internalization (PCI). scFvCD133/rGelonin was recombinantly constructed by fusing a gene (scFvCD133) encoding the scFv that targets both non-glycosylated and glycosylated forms of both human and murine CD133/prominin-1 to a gene encoding the ribosome-inactivating protein (RIP) gelonin (rGelonin). RIP-activity was assessed in a cell-free translation assay. Selective binding and intracellular accumulation of scFvCD133/rGelonin was evaluated by flow cytometry and fluorescence microscopy. PCI of scFvCD133/rGelonin was explored in CD133high and CD133low cell lines and a CD133neg cell line, where cytotoxicity was evaluated by the MTT assay. scFvCD133/rGelonin exhibited superior binding to and a higher accumulation in CD133high cells compared to CD133low cells. No cytotoxic responses were detected in either CD133high or CD133low cells after 72 h incubation with <100 nM scFvCD133/rGelonin. Despite a severe loss in RIP-activity of scFvCD133/rGelonin compared to free rGelonin, PCI of scFvCD133/rGelonin induced log-fold reduction of viability compared to PCI of rGelonin. Strikingly, PCI of scFvCD133/rGelonin exceeded the cytotoxicity of PCI of rGelonin also in CD133low cells. In conclusion, PCI promotes strong cytotoxic activity of the per se non-toxic scFvCD133/rGelonin in both CD133high and CD133low cancer cells.
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Affiliation(s)
- Cathrine Elisabeth Olsen
- Department of Radiation Biology, Institute for Cancer Research, Oslo University Hospital, The Norwegian Radium Hospital, N-0310 Oslo, Norway; (C.E.O.); (A.W.); (K.B.)
| | - Lawrence H. Cheung
- Department of Experimental Therapeutics, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA; (L.H.C.); (M.G.R.)
| | - Anette Weyergang
- Department of Radiation Biology, Institute for Cancer Research, Oslo University Hospital, The Norwegian Radium Hospital, N-0310 Oslo, Norway; (C.E.O.); (A.W.); (K.B.)
| | - Kristian Berg
- Department of Radiation Biology, Institute for Cancer Research, Oslo University Hospital, The Norwegian Radium Hospital, N-0310 Oslo, Norway; (C.E.O.); (A.W.); (K.B.)
| | - Daniel A. Vallera
- Department of Therapeutic Radiology-Radiation Oncology, University of Minnesota, Masonic Cancer Center, Minneapolis, MN 55455, USA;
| | - Michael G. Rosenblum
- Department of Experimental Therapeutics, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA; (L.H.C.); (M.G.R.)
| | - Pål Kristian Selbo
- Department of Radiation Biology, Institute for Cancer Research, Oslo University Hospital, The Norwegian Radium Hospital, N-0310 Oslo, Norway; (C.E.O.); (A.W.); (K.B.)
- Correspondence: ; Tel.: +47-22781469
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65
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Elsabbagh RA, Abdel Rahman MF, Hassanein SI, Hanafi RS, Assal RA, Shaban GM, Gad MZ. The association of megalin and cubilin genetic variants with serum levels of 25-hydroxvitamin D and the incidence of acute coronary syndrome in Egyptians: A case control study. J Adv Res 2019; 21:49-56. [PMID: 31641537 PMCID: PMC6796724 DOI: 10.1016/j.jare.2019.09.006] [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: 08/09/2019] [Revised: 09/19/2019] [Accepted: 09/23/2019] [Indexed: 12/17/2022] Open
Abstract
Megalin and cubilin are two receptors that mediate endocytosis of 25-hydroxyvitamin D (25(OH)D) for its final activation by hydroxylation. The aim of the present study was to evaluate the association of polymorphisms in megalin (rs2075252 and rs4668123) and cubilin (rs1801222 and rs12766939) with the circulating serum levels of 25(OH)D and with the early incidence of acute coronary syndrome (ACS) in Egyptians. The study included 328 subjects; 185 ACS patients aged between 27 and 60 years, and 143 healthy age-matched controls. Genotyping of cubilin rs12766939 Single Nucleotide Polymorphism (SNP) was performed using Real-Time Polymerase Chain Reaction (qPCR) and for megalin rs4668123 and rs2075252 and cubilin rs1801222 by Polymerase Chain Reaction- Restriction Fragment Length Polymorphism (PCR-RFLP). 25(OH)D levels were measured by Ultra Performance Liquid Chromatography- Tandem Mass Spectroscopy (UPLC-MS/MS). Results showed that vitamin D deficiency was highly linked to ACS incidence (P < 0.0001). The megalin rs4668123 CC, cubilin rs1801222 GG and cubilin rs12766939 GG + GA genotypes are associated with a higher ACS incidence and can be considered risk factors, according to Chi-squared test (P = 0.0003, 0.0442, 0.013 respectively). Conversely, the megalin rs2075252 SNP was not associated with increased ACS incidence. However, after performing multiple logistic regression analysis, only the megalin rs4668123 SNP was considered an independent ACS risk factor. Furthermore, the megalin rs4668123 CC genotype was associated with lower 25(OH)D levels (P = 0.0018). In conclusion, megalin rs4668123 (CC) was linked to lower 25(OH)D levels and can be considered an independent risk factor for incidence of ACS.
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Affiliation(s)
- Raghda A. Elsabbagh
- Clinical Biochemistry Unit, Faculty of Pharmacy and Biotechnology, The German University in Cairo, Egypt
| | - Mohamed F. Abdel Rahman
- Biochemistry Department, Faculty of Pharmacy, October University for Modern Science and Arts, 6th of October City, Egypt
| | - Sally I. Hassanein
- Clinical Biochemistry Unit, Faculty of Pharmacy and Biotechnology, The German University in Cairo, Egypt
| | - Rasha S. Hanafi
- Department of Pharmaceutical Chemistry, Faculty of Pharmacy and Biotechnology, The German University in Cairo, Egypt
| | - Reem A. Assal
- Department of Pharmacology and Toxicology, Faculty of Pharmacy and Biotechnology, The German University in Cairo, Egypt
| | | | - Mohamed Z. Gad
- Clinical Biochemistry Unit, Faculty of Pharmacy and Biotechnology, The German University in Cairo, Egypt
- Corresponding author.
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66
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Gliozzi ML, Rbaibi Y, Long KR, Vitturi DA, Weisz OA. Hemoglobin alters vitamin carrier uptake and vitamin D metabolism in proximal tubule cells: implications for sickle cell disease. Am J Physiol Cell Physiol 2019; 317:C993-C1000. [PMID: 31509446 DOI: 10.1152/ajpcell.00287.2019] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Kidney disease, including proximal tubule (PT) dysfunction, and vitamin D deficiency are among the most prevalent complications in sickle cell disease (SCD) patients. Although these two comorbidities have never been linked in SCD, the PT is the primary site for activation of vitamin D. Precursor 25-hydroxyvitamin D [25(OH)D] bound to vitamin D-binding protein (DBP) is taken up by PT cells via megalin/cubilin receptors, hydroxylated to the active 1,25-dihydroxyvitamin D [1,25(OH)2D] form, and released into the bloodstream. We tested the hypothesis that cell-free hemoglobin (Hb) filtered into the PT lumen impairs vitamin D uptake and metabolism. Hb at concentrations expected to be chronically present in the ultrafiltrate of SCD patients competed directly with DBP for apical uptake by PT cells. By contrast, uptake of retinol binding protein was impaired only at considerably higher Hb concentrations. Prolonged exposure to Hb led to increased oxidative stress in PT cells and to a selective increase in mRNA levels of the CYP27B1 hydroxylase, although protein levels were unchanged. Hb exposure also impaired vitamin D metabolism in PT cells, resulting in reduced ratio of 1,25(OH)2D:25(OH)D. Moreover, plasma levels of 1,25(OH)2D were reduced in a mouse model of SCD. Together, our data suggest that Hb released by chronic hemolysis has multiple effects on PT function that contribute to vitamin D deficiency in SCD patients.
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Affiliation(s)
- Megan L Gliozzi
- Renal-Electrolyte Division, Department of Medicine, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
| | - Youssef Rbaibi
- Renal-Electrolyte Division, Department of Medicine, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
| | - Kimberly R Long
- Renal-Electrolyte Division, Department of Medicine, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
| | - Dario A Vitturi
- Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania.,Pittsburgh Heart, Lung, and Blood Vascular Medicine Institute, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
| | - Ora A Weisz
- Renal-Electrolyte Division, Department of Medicine, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania.,Pittsburgh Heart, Lung, and Blood Vascular Medicine Institute, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
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67
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Arakawa Y, Ushijima K, Tsuchiya H, Morishige JI, Mii A, Ando H, Tsuruoka SI, Fujimura A. Influence of renal ischaemia-reperfusion injury on renal neutrophil gelatinase-associated lipocalin receptor (24p3R) in rats. Clin Exp Pharmacol Physiol 2019; 46:1166-1173. [PMID: 31211866 DOI: 10.1111/1440-1681.13129] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2018] [Revised: 06/02/2019] [Accepted: 06/13/2019] [Indexed: 11/29/2022]
Abstract
The neutrophil gelatinase-associated lipocalin (NGAL) receptor (24p3R) is expressed in distal nephron and contributes to the endocytosis of NGAL in urine. This study was undertaken to evaluate an influence of renal ischaemia-reperfusion injury on 24p3R. Unilateral renal pedicle was clamped for 0, 10, 20, 30, or 45 minutes in male Wistar rats. Urine was collected for 24 hours after reperfusion, and ischaemic kidney and blood sample were obtained. Apparent histological injury in the ischaemic kidney was detected in the 30 and 45 minutes-treated groups. Urinary NGAL excretion elevated in rats with renal ischaemia for more than 20 minutes, while serum creatinine increased in rats for more than 30 minutes of ischaemia. Renal protein expression of NGAL did not significantly change. Renal mRNA expressions of megalin and cubilin, which are expressed at renal proximal tubules and uptake NGAL, decreased in animals with renal ischaemia for more than 20 minutes. Renal protein expression of 24p3R, which is expressed at renal distal tubules and uptake NGAL, decreased in rats with renal ischaemia for 45 min. This study showed for the first time that renal 24p3R decreased in response to renal ischaemia. As relatively longer renal ischaemia (45 minutes) decreased renal 24p3R protein and increased urinary NGAL excretion, the down-regulation of 24p3R protein might contribute to the elevated urinary excretion of NGAL in rats with unilateral ischaemia-reperfusion injury.
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Affiliation(s)
- Yusuke Arakawa
- Division of Nephrology, Nippon Medical School, Tokyo, Japan.,Divisions of Clinical Pharmacology, Department of Pharmacology, Jichi Medical University, Tochigi, Japan
| | - Kentaro Ushijima
- Divisions of Clinical Pharmacology, Department of Pharmacology, Jichi Medical University, Tochigi, Japan
| | - Hiroyoshi Tsuchiya
- Divisions of Molecular Pharmacology, Department of Pharmacology, Jichi Medical University, Tochigi, Japan
| | - Jun-Ichi Morishige
- Department of Cellular and Molecular Function Analysis, Kanazawa University, Ishikawa, Japan
| | - Akiko Mii
- Division of Nephrology, Nippon Medical School, Tokyo, Japan
| | - Hitoshi Ando
- Department of Cellular and Molecular Function Analysis, Kanazawa University, Ishikawa, Japan
| | | | - Akio Fujimura
- Divisions of Clinical Pharmacology, Department of Pharmacology, Jichi Medical University, Tochigi, Japan
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68
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Knoppert SN, Valentijn FA, Nguyen TQ, Goldschmeding R, Falke LL. Cellular Senescence and the Kidney: Potential Therapeutic Targets and Tools. Front Pharmacol 2019; 10:770. [PMID: 31354486 PMCID: PMC6639430 DOI: 10.3389/fphar.2019.00770] [Citation(s) in RCA: 43] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2019] [Accepted: 06/14/2019] [Indexed: 01/10/2023] Open
Abstract
Chronic kidney disease (CKD) is an increasing health burden (affecting approximately 13.4% of the population). Currently, no curative treatment options are available and treatment is focused on limiting the disease progression. The accumulation of senescent cells has been implicated in the development of kidney fibrosis by limiting tissue rejuvenation and through the secretion of pro-fibrotic and pro-inflammatory mediators termed as the senescence-associated secretory phenotype. The clearance of senescent cells in aging models results in improved kidney function, which shows promise for the options of targeting senescent cells in CKD. There are several approaches for the development of “senotherapies”, the most rigorous of which is the elimination of senescent cells by the so-called senolytic drugs either newly developed or repurposed for off-target effects in terms of selectively inducing apoptosis in senescent cells. Several chemotherapeutics and checkpoint inhibitors currently used in daily oncological practice show senolytic properties. However, the applicability of such senolytic compounds for the treatment of renal diseases has hardly been investigated. A serious concern is that systemic side effects will limit the use of senolytics for kidney fibrosis. Specifically targeting senescent cells and/or targeted drug delivery to the kidney might circumvent these side effects. In this review, we discuss the connection between CKD and senescence, the pharmacological options for targeting senescent cells, and the means to specifically target the kidney.
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Affiliation(s)
- Sebastian N Knoppert
- Department of Pathology, University Medical Center Utrecht, Utrecht, Netherlands
| | - Floris A Valentijn
- Department of Pathology, University Medical Center Utrecht, Utrecht, Netherlands
| | - Tri Q Nguyen
- Department of Pathology, University Medical Center Utrecht, Utrecht, Netherlands
| | - Roel Goldschmeding
- Department of Pathology, University Medical Center Utrecht, Utrecht, Netherlands
| | - Lucas L Falke
- Department of Pathology, University Medical Center Utrecht, Utrecht, Netherlands.,Department of Internal Medicine, Diakonessenhuis, University Medical Center Utrecht, Utrecht, Netherlands
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69
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Storm T, Burgoyne T, Dunaief JL, Christensen EI, Futter C, Nielsen R. Selective Ablation of Megalin in the Retinal Pigment Epithelium Results in Megaophthalmos, Macromelanosome Formation and Severe Retina Degeneration. Invest Ophthalmol Vis Sci 2019; 60:322-330. [PMID: 30665232 PMCID: PMC6343679 DOI: 10.1167/iovs.18-25667] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Purpose Mutations in the megalin-encoding gene, LRP2, cause high myopia as seen in patients suffering from Donnai-Barrow/facio-oculo-acoustico-renal syndrome. Megalin is present in both the nonpigmented epithelium of the ciliary body and in the RPE. In this study, we set out to establish an animal model to study the mechanisms underlying the ocular phenotype and to establish if high myopia/megaophthalmos is induced by postnatal megalin-deficiency in the RPE. Methods Postnatal RPE-specific deletion of megalin was generated by crossing mice bearing a homozygous loxP-flanked Lrp2 allele with transgenic mice expressing the Cre recombinase driven by the BEST1 promotor. The model was investigated by immunohistologic techniques, and transmission electron microscopy. Results Mice with postnatal RPE-specific loss of megalin developed a megaophthalmos phenotype with dramatic increase in ocular size and severe retinal thinning associated with compromised vision. This phenotype was present at postnatal day 14, indicating rapid development in the period from onset of BEST1 promotor activity at postnatal day 10. Additionally, RPE melanosomes exhibited abnormal size and morphology, suggested by electron tomography to be caused by fusion events between multiple melanosomes. Conclusions Postnatal loss of megalin in the RPE induces dramatic and rapid ocular growth and retinal degeneration compatible with the high myopia observed in Donnai-Barrow patients. The morphologic changes of RPE melanosomes, believed to be largely inert and fully differentiated at birth, suggested a continued plasticity of mature melanosomes and a requirement for megalin to maintain their number and morphology.
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Affiliation(s)
- Tina Storm
- Department of Biomedicine, Faculty of Health Sciences, Aarhus University, Aarhus, Denmark
| | | | - Joshua L Dunaief
- F.M. Kirby Center for Molecular Ophthalmology, Scheie Eye Institute, University of Pennsylvania, Philadelphia, Pennsylvania, United States
| | - Erik I Christensen
- Department of Biomedicine, Faculty of Health Sciences, Aarhus University, Aarhus, Denmark
| | - Clare Futter
- UCL Institute of Ophthalmology, London, United Kingdom
| | - Rikke Nielsen
- Department of Biomedicine, Faculty of Health Sciences, Aarhus University, Aarhus, Denmark
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70
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Affiliation(s)
- Andrew M Hall
- Institute of Anatomy, University of Zurich, Zurich, Switzerland; .,Department of Nephrology, University Hospital Zurich, Zurich, Switzerland
| | - Robert J Unwin
- Department of Renal Medicine, University College London, London, United Kingdom; and.,CVRM Biopharmaceuticals R&D, AstraZeneca, Gothenburg, Sweden
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71
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Prange JA, Aleandri S, Komisarski M, Luciani A, Käch A, Schuh CD, Hall AM, Mezzenga R, Devuyst O, Landau EM. Overcoming Endocytosis Deficiency by Cubosome Nanocarriers. ACS APPLIED BIO MATERIALS 2019; 2:2490-2499. [DOI: 10.1021/acsabm.9b00187] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Affiliation(s)
- Jenny A. Prange
- Institute of Physiology, University of Zurich, Zurich 8057, Switzerland
| | - Simone Aleandri
- Department of Chemistry, University of Zurich, Zurich 8057, Switzerland
| | - Marek Komisarski
- Department of Chemistry, University of Zurich, Zurich 8057, Switzerland
| | | | - Andres Käch
- Center for Microscopy and Image Analysis, University of Zurich, Zurich 8057, Switzerland
| | | | - Andrew M. Hall
- Institute of Anatomy, University of Zurich, Zurich 8057, Switzerland
| | - Raffaele Mezzenga
- Department of Health Sciences & Technology, ETH Zurich, Zurich 8092, Switzerland
| | - Olivier Devuyst
- Institute of Physiology, University of Zurich, Zurich 8057, Switzerland
| | - Ehud M. Landau
- Department of Chemistry, University of Zurich, Zurich 8057, Switzerland
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72
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Gravotta D, Perez Bay A, Jonker CTH, Zager PJ, Benedicto I, Schreiner R, Caceres PS, Rodriguez-Boulan E. Clathrin and clathrin adaptor AP-1 control apical trafficking of megalin in the biosynthetic and recycling routes. Mol Biol Cell 2019; 30:1716-1728. [PMID: 31091172 PMCID: PMC6727755 DOI: 10.1091/mbc.e18-12-0811] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
Megalin (gp330, LRP-2) is a protein structurally related to the low-density lipoprotein receptor family that displays a large luminal domain with multiligand binding properties. Megalin localizes to the apical surface of multiple epithelia, where it participates in endocytosis of a variety of ligands performing roles important for development or homeostasis. We recently described the apical recycling pathway of megalin in Madin–Darby canine kidney (MDCK) cells and found that it is a long-lived, fast recycling receptor with a recycling turnover of 15 min and a half-life of 4.8 h. Previous work implicated clathrin and clathrin adaptors in the polarized trafficking of fast recycling basolateral receptors. Hence, here we study the role of clathrin and clathrin adaptors in megalin’s apical localization and trafficking. Targeted silencing of clathrin or the γ1 subunit of clathrin adaptor AP-1 by RNA interference in MDCK cells disrupted apical localization of megalin, causing its redistribution to the basolateral membrane. In contrast, silencing of the γ2 subunit of AP-1 had no effect on megalin polarity. Trafficking assays we developed using FM4-HA-miniMegalin-GFP, a reversible conditional endoplasmic reticulum–retained chimera, revealed that clathrin and AP-1 silencing disrupted apical sorting of megalin in both biosynthetic and recycling routes. Our experiments demonstrate that clathrin and AP-1 control the sorting of an apical transmembrane protein.
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Affiliation(s)
- Diego Gravotta
- Margaret Dyson Vision Research Institute, Weill Cornell Medicine, New York, NY 10065
| | - Andres Perez Bay
- Margaret Dyson Vision Research Institute, Weill Cornell Medicine, New York, NY 10065
| | - Caspar T H Jonker
- Margaret Dyson Vision Research Institute, Weill Cornell Medicine, New York, NY 10065
| | - Patrick J Zager
- Margaret Dyson Vision Research Institute, Weill Cornell Medicine, New York, NY 10065
| | - Ignacio Benedicto
- Margaret Dyson Vision Research Institute, Weill Cornell Medicine, New York, NY 10065
| | - Ryan Schreiner
- Margaret Dyson Vision Research Institute, Weill Cornell Medicine, New York, NY 10065
| | - Paulo S Caceres
- Margaret Dyson Vision Research Institute, Weill Cornell Medicine, New York, NY 10065
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73
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Fels J, Scharner B, Zarbock R, Zavala Guevara IP, Lee WK, Barbier OC, Thévenod F. Cadmium Complexed with β2-Microglubulin, Albumin and Lipocalin-2 rather than Metallothionein Cause Megalin:Cubilin Dependent Toxicity of the Renal Proximal Tubule. Int J Mol Sci 2019; 20:ijms20102379. [PMID: 31091675 PMCID: PMC6566203 DOI: 10.3390/ijms20102379] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2019] [Revised: 05/03/2019] [Accepted: 05/09/2019] [Indexed: 11/25/2022] Open
Abstract
Cadmium (Cd2+) in the environment is a significant health hazard. Chronic low Cd2+ exposure mainly results from food and tobacco smoking and causes kidney damage, predominantly in the proximal tubule. Blood Cd2+ binds to thiol-containing high (e.g., albumin, transferrin) and low molecular weight proteins (e.g., the high-affinity metal-binding protein metallothionein, β2-microglobulin, α1-microglobulin and lipocalin-2). These plasma proteins reach the glomerular filtrate and are endocytosed at the proximal tubule via the multiligand receptor complex megalin:cubilin. The current dogma of chronic Cd2+ nephrotoxicity claims that Cd2+-metallothionein endocytosed via megalin:cubilin causes renal damage. However, a thorough study of the literature strongly argues for revision of this model for various reasons, mainly: (i) It relied on studies with unusually high Cd2+-metallothionein concentrations; (ii) the KD of megalin for metallothionein is ~105-times higher than (Cd2+)-metallothionein plasma concentrations. Here we investigated the uptake and toxicity of ultrafiltrated Cd2+-binding protein ligands that are endocytosed via megalin:cubilin in the proximal tubule. Metallothionein, β2-microglobulin, α1-microglobulin, lipocalin-2, albumin and transferrin were investigated, both as apo- and Cd2+-protein complexes, in a rat proximal tubule cell line (WKPT-0293 Cl.2) expressing megalin:cubilin at low passage, but is lost at high passage. Uptake was determined by fluorescence microscopy and toxicity by MTT cell viability assay. Apo-proteins in low and high passage cells as well as Cd2+-protein complexes in megalin:cubilin deficient high passage cells did not affect cell viability. The data prove Cd2+-metallothionein is not toxic, even at >100-fold physiological metallothionein concentrations in the primary filtrate. Rather, Cd2+-β2-microglobulin, Cd2+-albumin and Cd2+-lipocalin-2 at concentrations present in the primary filtrate are taken up by low passage proximal tubule cells and cause toxicity. They are therefore likely candidates of Cd2+-protein complexes damaging the proximal tubule via megalin:cubilin at concentrations found in the ultrafiltrate.
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Affiliation(s)
- Johannes Fels
- Department of Physiology, Pathophysiology & Toxicology and ZBAF (Centre for Biomedical Education and Research), Faculty of Health, School of Medicine, Witten/Herdecke University, D-58453 Witten, Germany.
| | - Bettina Scharner
- Department of Physiology, Pathophysiology & Toxicology and ZBAF (Centre for Biomedical Education and Research), Faculty of Health, School of Medicine, Witten/Herdecke University, D-58453 Witten, Germany.
| | - Ralf Zarbock
- Department of Physiology, Pathophysiology & Toxicology and ZBAF (Centre for Biomedical Education and Research), Faculty of Health, School of Medicine, Witten/Herdecke University, D-58453 Witten, Germany.
| | - Itzel Pamela Zavala Guevara
- Departamento de Toxicología, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional (CINVESTAV-IPN), Mexico 07360, México.
| | - Wing-Kee Lee
- Department of Physiology, Pathophysiology & Toxicology and ZBAF (Centre for Biomedical Education and Research), Faculty of Health, School of Medicine, Witten/Herdecke University, D-58453 Witten, Germany.
| | - Olivier C Barbier
- Departamento de Toxicología, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional (CINVESTAV-IPN), Mexico 07360, México.
| | - Frank Thévenod
- Department of Physiology, Pathophysiology & Toxicology and ZBAF (Centre for Biomedical Education and Research), Faculty of Health, School of Medicine, Witten/Herdecke University, D-58453 Witten, Germany.
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74
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Acute Tubular Injury is Associated With Severe Traumatic Brain Injury: in Vitro Study on Human Tubular Epithelial Cells. Sci Rep 2019; 9:6090. [PMID: 30988316 PMCID: PMC6465296 DOI: 10.1038/s41598-019-42147-4] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2018] [Accepted: 03/15/2019] [Indexed: 01/12/2023] Open
Abstract
Acute kidney injury following traumatic brain injury is associated with poor outcome. We investigated in vitro the effects of plasma of brain injured patients with acute tubular kidney injury on kidney tubular epithelial cell function. we performed a prospective observational clinical study in ICU in a trauma centre of the University hospital in Italy including twenty-three ICU patients with traumatic brain injury consecutively enrolled. Demographic data were recorded on admission: age 39 ± 19, Glasgow Coma Score 5 (3–8). Neutrophil Gelatinase-Associated Lipocalin and inflammatory mediators were measured in plasma on admission and after 24, 48 and 72 hours; urine were collected for immunoelectrophoresis having healthy volunteers as controls. Human renal proximal tubular epithelial cells were stimulated with patients or controls plasma. Adhesion of freshly isolated human neutrophils and trans-epithelial electrical resistance were assessed; cell viability (XTT assay), apoptosis (TUNEL staining), Neutrophil Gelatinase-Associated Lipocalin and Megalin expression (quantitative real-time PCR) were measured. All patients with normal serum creatinine showed increased plasmatic Neutrophil Gelatinase-Associated Lipocalin and increased urinary Retinol Binding Protein and α1-microglobulin. Neutrophil Gelatinase-Associated Lipocalin was significantly correlated with both inflammatory mediators and markers of tubular damage. Patient’ plasma incubated with tubular cells significantly increased adhesion of neutrophils, reduced trans-epithelial electrical resistance, exerted a cytotoxic effect and triggered apoptosis and down-regulated the endocytic receptor Megalin compared to control. Plasma of brain injured patients with increased markers of subclinical acute kidney induced a pro-inflammatory phenotype, cellular dysfunction and apoptotic death in tubular epithelial cells.
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75
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Smith CP, Lee WK, Haley M, Poulsen SB, Thévenod F, Fenton RA. Proximal tubule transferrin uptake is modulated by cellular iron and mediated by apical membrane megalin-cubilin complex and transferrin receptor 1. J Biol Chem 2019; 294:7025-7036. [PMID: 30833328 PMCID: PMC6497946 DOI: 10.1074/jbc.ra118.006390] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2018] [Revised: 02/27/2019] [Indexed: 01/12/2023] Open
Abstract
Receptor-mediated endocytosis is responsible for reabsorption of transferrin (Tf) in renal proximal tubules (PTs). Although the role of the megalin-cubilin receptor complex (MCRC) in this process is unequivocal, modalities independent of this complex are evident but as yet undefined. Here, using immunostaining and Tf-flux assays, FACS analysis, and fluorescence imaging, we report localization of Tf receptor 1 (TfR1), the cognate Tf receptor mediating cellular holo-Tf (hTf) acquisition, to the apical brush border of the PT, with expression gradually declining along the PT in mouse and rat kidneys. In functional studies, hTf uptake across the apical membrane of cultured PT epithelial cell (PTEC) monolayers increased in response to decreased cellular iron after desferrioxamine (DFO) treatment. We also found that apical hTf uptake under basal conditions is receptor-associated protein (RAP)-sensitive and therefore mediated by the MCRC but becomes RAP-insensitive under DFO treatment, with concomitantly decreased megalin and cubilin expression levels and increased TfR1 expression. Thus, as well as the MCRC, TfR1 mediates hTf uptake across the PT apical brush border, but in conditions of decreased cellular iron, hTf uptake is predominated by augmented apical TfR1. In conclusion, both the MCRC and TfR1 mediate hTf uptake across apical brush border membranes of PTECs and reciprocally respond to decreased cellular iron. Our findings have implications for renal health, whole-body iron homeostasis, and pathologies arising from disrupted iron balance.
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Affiliation(s)
- Craig P Smith
- From the School of Medical Sciences, The University of Manchester, Manchester M13 9PT, United Kingdom,
| | - Wing-Kee Lee
- Physiology, Pathophysiology and Toxicology, University of Witten/Herdecke, D-58453 Witten, Germany, and
| | - Matthew Haley
- From the School of Medical Sciences, The University of Manchester, Manchester M13 9PT, United Kingdom
| | - Søren B Poulsen
- Department of Biomedicine, Aarhus University, Aarhus, 8000 Denmark
| | - Frank Thévenod
- Physiology, Pathophysiology and Toxicology, University of Witten/Herdecke, D-58453 Witten, Germany, and
| | - Robert A Fenton
- Department of Biomedicine, Aarhus University, Aarhus, 8000 Denmark
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76
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Atangcho L, Navaratna T, Thurber GM. Hitting Undruggable Targets: Viewing Stabilized Peptide Development through the Lens of Quantitative Systems Pharmacology. Trends Biochem Sci 2019; 44:241-257. [PMID: 30563724 PMCID: PMC6661118 DOI: 10.1016/j.tibs.2018.11.008] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2018] [Revised: 08/31/2018] [Accepted: 11/22/2018] [Indexed: 01/10/2023]
Abstract
Stabilized peptide therapeutics have the potential to hit currently undruggable targets, dramatically expanding the druggable genome. However, major obstacles to their development include poor intracellular delivery, rapid degradation, low target affinity, and membrane toxicity. With the emergence of multiple stabilization techniques and screening technologies, the high efficacy of various bioactive peptides has been demonstrated in vitro, albeit with limited success in vivo. We discuss here the chemical and pharmacokinetic barriers to achieving in vivo efficacy, analyze the characteristics of FDA-approved peptide drugs, and propose a developmental tool that considers the molecular properties of stabilized peptides in a comprehensive and quantitative manner to achieve the necessary rates for in vivo delivery to the target, efficacy, and ultimately clinical translation.
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Affiliation(s)
- Lydia Atangcho
- Department of Chemical Engineering, University of Michigan, Ann Arbor, MI, USA
| | - Tejas Navaratna
- Department of Chemical Engineering, University of Michigan, Ann Arbor, MI, USA
| | - Greg M Thurber
- Department of Chemical Engineering, University of Michigan, Ann Arbor, MI, USA; Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI, USA.
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77
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Iron uptake by ZIP8 and ZIP14 in human proximal tubular epithelial cells. Biometals 2019; 32:211-226. [PMID: 30806852 PMCID: PMC6437295 DOI: 10.1007/s10534-019-00183-7] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2018] [Accepted: 12/14/2018] [Indexed: 12/11/2022]
Abstract
In patients with iron overload disorders, increasing number of reports of renal dysfunction and renal iron deposition support an association between increased iron exposure and renal injury. In systemic iron overload, elevated circulating levels of transferrin-bound (TBI) and non-transferrin-bound iron (NTBI) are filtered to the renal proximal tubules, where they may cause injury. However, the mechanisms of tubular iron handling remain elusive. To unravel molecular renal proximal tubular NTBI and TBI handling, human conditionally immortalized proximal tubular epithelial cells (ciPTECs) were incubated with 55Fe as NTBI and fluorescently labeled holo-transferrin as TBI. Ferrous iron importers ZIP8 and ZIP14 were localized in the ciPTEC plasma membrane. Whereas silencing of either ZIP8 or ZIP14 alone did not affect 55Fe uptake, combined silencing significantly reduced 55Fe uptake compared to control (p < 0.05). Furthermore, transferrin receptor 1 (TfR1) and ZIP14, but not ZIP8, colocalized with early endosome antigen 1 (EEA1). TfR1 and ZIP14 also colocalized with uptake of fluorescently labeled transferrin. Furthermore, ZIP14 silencing decreased 55Fe uptake after 55Fe-Transferrin exposure (p < 0.05), suggesting ZIP14 could be involved in early endosomal transport of TBI-derived iron into the cytosol. Our data suggest that human proximal tubular epithelial cells take up TBI and NTBI, where ZIP8 and ZIP14 are both involved in NTBI uptake, but ZIP14, not ZIP8, mediates TBI-derived iron uptake. This knowledge provides more insights in the mechanisms of renal iron handling and suggests that ZIP8 and ZIP14 could be potential targets for limiting renal iron reabsorption and enhancing urinary iron excretion in systemic iron overload disorders.
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78
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Channels, transporters and receptors for cadmium and cadmium complexes in eukaryotic cells: myths and facts. Biometals 2019; 32:469-489. [DOI: 10.1007/s10534-019-00176-6] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2019] [Accepted: 01/21/2019] [Indexed: 12/21/2022]
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79
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Shrestha S, Sunaga H, Hanaoka H, Yamaguchi A, Kuwahara S, Umbarawan Y, Nakajima K, Machida T, Murakami M, Saito A, Tsushima Y, Kurabayashi M, Iso T. Circulating FABP4 is eliminated by the kidney via glomerular filtration followed by megalin-mediated reabsorption. Sci Rep 2018; 8:16451. [PMID: 30401801 PMCID: PMC6219568 DOI: 10.1038/s41598-018-34902-w] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2018] [Accepted: 10/28/2018] [Indexed: 01/15/2023] Open
Abstract
Circulating fatty acid binding protein 4 (FABP4), secreted from adipocytes, is a potential biomarker for metabolic and cardiovascular diseases. Circulating FABP4 levels are positively associated with adiposity and adrenergic stimulation, but negatively with renal function. In this study, we addressed the issue of how the kidney regulates clearance of circulating FABP4. Tracing study revealed remarkable accumulation of 125I-labeled FABP4 in the kidney. Exogenous FABP4 was exclusively detected in the apical membrane of proximal tubule epithelial cells (PTECs). Bilateral nephrectomy resulted in marked elevation of circulating FABP4 levels. Accelerated lipolysis by β-3 adrenergic stimulation led to a marked elevation in circulating FABP4 in mice with severe renal dysfunction. Megalin, an endocytic receptor expressed in PTECs, plays a major role in reabsorption of proteins filtered through glomeruli. Quartz-crystal microbalance study revealed that FABP4 binds to megalin. In kidney-specific megalin knockout mice, a large amount of FABP4 was excreted in urine while circulating FABP4 levels were significantly reduced. Our data suggest that circulating FABP4 is processed by the kidney via the glomerular filtration followed by megalin-mediated reabsorption. Thus, it is likely that circulating FABP4 levels are determined mainly by balance between secretion rate of FABP4 from adipocytes and clearance rate of the kidney.
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Affiliation(s)
- Suman Shrestha
- Department of Diagnostic Radiology and Nuclear Medicine, Gunma University Graduate School of Medicine, 3-39-22 Showa-machi, Maebashi, Gunma, 371-8511, Japan
| | - Hiroaki Sunaga
- Department of Cardiovascular Medicine, Gunma University Graduate School of Medicine, 3-39-22 Showa-machi, Maebashi, Gunma, 371-8511, Japan
| | - Hirofumi Hanaoka
- Department of Bioimaging Information Analysis, Gunma University Graduate School of Medicine, 3-39-22 Showa-machi, Maebashi, Gunma, 371-8511, Japan
| | - Aiko Yamaguchi
- Department of Bioimaging Information Analysis, Gunma University Graduate School of Medicine, 3-39-22 Showa-machi, Maebashi, Gunma, 371-8511, Japan
| | - Shoji Kuwahara
- Department of Applied Molecular Medicine, Niigata University Graduate School of Medical and Dental Sciences, 1-757 Asahimachi-dori, Chuo-ku, Niigata, 951-8585, Japan
| | - Yogi Umbarawan
- Department of Cardiovascular Medicine, Gunma University Graduate School of Medicine, 3-39-22 Showa-machi, Maebashi, Gunma, 371-8511, Japan.,Department of Internal Medicine, Faculty of Medicine Universitas Indonesia, Jl. Salemba Raya No. 6, Jakarta, 10430, Indonesia
| | - Kiyomi Nakajima
- Department of Clinical Laboratory Medicine, Gunma University Graduate School of Medicine, 3-39-22 Showa-machi, Maebashi, Gunma, 371-8511, Japan
| | - Tetsuo Machida
- Department of Clinical Laboratory Medicine, Gunma University Graduate School of Medicine, 3-39-22 Showa-machi, Maebashi, Gunma, 371-8511, Japan
| | - Masami Murakami
- Department of Clinical Laboratory Medicine, Gunma University Graduate School of Medicine, 3-39-22 Showa-machi, Maebashi, Gunma, 371-8511, Japan
| | - Akihiko Saito
- Department of Applied Molecular Medicine, Niigata University Graduate School of Medical and Dental Sciences, 1-757 Asahimachi-dori, Chuo-ku, Niigata, 951-8585, Japan
| | - Yoshito Tsushima
- Department of Diagnostic Radiology and Nuclear Medicine, Gunma University Graduate School of Medicine, 3-39-22 Showa-machi, Maebashi, Gunma, 371-8511, Japan.,Research Program for Diagnostic and Molecular Imaging, Division of Integrated Oncology Research, Gunma University Initiative for Advanced Research (GIAR), 3-39-22 Showa-machi, Maebashi, Gunma, 371-8511, Japan
| | - Masahiko Kurabayashi
- Department of Cardiovascular Medicine, Gunma University Graduate School of Medicine, 3-39-22 Showa-machi, Maebashi, Gunma, 371-8511, Japan.,Program for obesity-related cardiovascular disease, Division of Endocrinology, Metabolism and Signaling, Gunma University Initiative for Advanced Research (GIAR), 3-39-22 Showa-machi, Maebashi, Gunma, 371-8511, Japan
| | - Tatsuya Iso
- Department of Cardiovascular Medicine, Gunma University Graduate School of Medicine, 3-39-22 Showa-machi, Maebashi, Gunma, 371-8511, Japan.
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80
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Weiss A, Spektor L, A. Cohen L, Lifshitz L, Magid Gold I, Zhang DL, Truman-Rosentsvit M, Leichtmann-Bardoogo Y, Nyska A, Addadi S, Rouault TA, Meyron-Holtz EG. Orchestrated regulation of iron trafficking proteins in the kidney during iron overload facilitates systemic iron retention. PLoS One 2018; 13:e0204471. [PMID: 30321179 PMCID: PMC6188744 DOI: 10.1371/journal.pone.0204471] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2018] [Accepted: 09/07/2018] [Indexed: 01/24/2023] Open
Abstract
The exact route of iron through the kidney and its regulation during iron overload are not completely elucidated. Under physiologic conditions, non-transferrin and transferrin bound iron passes the glomerular filter and is reabsorbed through kidney epithelial cells, so that hardly any iron is found in the urine. To study the route of iron reabsorption through the kidney, we analyzed the location and regulation of iron metabolism related proteins in kidneys of mice with iron overload, elicited by iron dextran injections. Transferrin Receptor 1 was decreased as expected, following iron overload. In contrast, the multi-ligand hetero-dimeric receptor-complex megalin/cubilin, which also mediates the internalization of transferrin, was highly up-regulated. Moreover, with increasing iron, intracellular ferritin distribution shifted in renal epithelium from an apical location to a punctate distribution throughout the epithelial cells. In addition, in contrast to many other tissues, the iron exporter ferroportin was not reduced by iron overload in the kidney. Iron accumulated mainly in interstitial macrophages, and more prominently in the medulla than in the cortex. This suggests that despite the reduction of Transferrin Receptor 1, alternative pathways may effectively mediate re-absorption of iron that cycles through the kidney during parenterally induced iron-overload. The most iron consuming process of the body, erythropoiesis, is regulated by the renal erythropoietin producing cells in kidney interstitium. We propose, that the efficient re-absorption of iron by the kidney, also during iron overload enables these cells to sense systemic iron and regulate its usage based on the systemic iron state.
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Affiliation(s)
- Avital Weiss
- Laboratory for Molecular Nutrition, Faculty of Biotechnology and Food Engineering, Technion-Israel Institute of Technology, Haifa, Israel
| | - Lior Spektor
- Laboratory for Molecular Nutrition, Faculty of Biotechnology and Food Engineering, Technion-Israel Institute of Technology, Haifa, Israel
| | - Lyora A. Cohen
- Laboratory for Molecular Nutrition, Faculty of Biotechnology and Food Engineering, Technion-Israel Institute of Technology, Haifa, Israel
| | - Lena Lifshitz
- Laboratory for Molecular Nutrition, Faculty of Biotechnology and Food Engineering, Technion-Israel Institute of Technology, Haifa, Israel
| | - Inbar Magid Gold
- Laboratory for Molecular Nutrition, Faculty of Biotechnology and Food Engineering, Technion-Israel Institute of Technology, Haifa, Israel
| | - De-Liang Zhang
- Molecular Medicine Program, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Marianna Truman-Rosentsvit
- Laboratory for Molecular Nutrition, Faculty of Biotechnology and Food Engineering, Technion-Israel Institute of Technology, Haifa, Israel
| | - Yael Leichtmann-Bardoogo
- Laboratory for Molecular Nutrition, Faculty of Biotechnology and Food Engineering, Technion-Israel Institute of Technology, Haifa, Israel
| | - Abraham Nyska
- Sackler School of Medicine, Tel Aviv University, and Consultant in Toxicologic Pathology, Timrat, Israel
| | | | - Tracey A. Rouault
- Molecular Medicine Program, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Esther G. Meyron-Holtz
- Laboratory for Molecular Nutrition, Faculty of Biotechnology and Food Engineering, Technion-Israel Institute of Technology, Haifa, Israel
- * E-mail:
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81
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Schuh CD, Polesel M, Platonova E, Haenni D, Gassama A, Tokonami N, Ghazi S, Bugarski M, Devuyst O, Ziegler U, Hall AM. Combined Structural and Functional Imaging of the Kidney Reveals Major Axial Differences in Proximal Tubule Endocytosis. J Am Soc Nephrol 2018; 29:2696-2712. [PMID: 30301861 DOI: 10.1681/asn.2018050522] [Citation(s) in RCA: 68] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2018] [Accepted: 09/18/2018] [Indexed: 12/13/2022] Open
Abstract
BACKGROUND The kidney proximal convoluted tubule (PCT) reabsorbs filtered macromolecules via receptor-mediated endocytosis (RME) or nonspecific fluid phase endocytosis (FPE); endocytosis is also an entry route for disease-causing toxins. PCT cells express the protein ligand receptor megalin and have a highly developed endolysosomal system (ELS). Two PCT segments (S1 and S2) display subtle differences in cellular ultrastructure; whether these translate into differences in endocytotic function has been unknown. METHODS To investigate potential differences in endocytic function in S1 and S2, we quantified ELS protein expression in mouse kidney PCTs using real-time quantitative polymerase chain reaction and immunostaining. We also used multiphoton microscopy to visualize uptake of fluorescently labeled ligands in both living animals and tissue cleared using a modified CLARITY approach. RESULTS Uptake of proteins by RME occurs almost exclusively in S1. In contrast, dextran uptake by FPE takes place in both S1 and S2, suggesting that RME and FPE are discrete processes. Expression of key ELS proteins, but not megalin, showed a bimodal distribution; levels were far higher in S1, where intracellular distribution was also more polarized. Tissue clearing permitted imaging of ligand uptake at single-organelle resolution in large sections of kidney cortex. Analysis of segmented tubules confirmed that, compared with protein uptake, dextran uptake occurred over a much greater length of the PCT, although individual PCTs show marked heterogeneity in solute uptake length and three-dimensional morphology. CONCLUSIONS Striking axial differences in ligand uptake and ELS function exist along the PCT, independent of megalin expression. These differences have important implications for understanding topographic patterns of kidney diseases and the origins of proteinuria.
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Affiliation(s)
| | | | | | - Dominik Haenni
- Institute of Anatomy.,Center for Microscopy and Image Analysis, and
| | - Alkaly Gassama
- Institute of Physiology, University of Zurich, Zurich, Switzerland; and
| | - Natsuko Tokonami
- Institute of Physiology, University of Zurich, Zurich, Switzerland; and
| | | | | | - Olivier Devuyst
- Institute of Physiology, University of Zurich, Zurich, Switzerland; and
| | - Urs Ziegler
- Center for Microscopy and Image Analysis, and
| | - Andrew M Hall
- Institute of Anatomy, .,Department of Nephrology, University Hospital Zurich, Zurich, Switzerland
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82
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Yasuike M, Iwasaki Y, Nishiki I, Nakamura Y, Matsuura A, Yoshida K, Noda T, Andoh T, Fujiwara A. The yellowtail (Seriola quinqueradiata) genome and transcriptome atlas of the digestive tract. DNA Res 2018; 25:547-560. [PMID: 30329019 PMCID: PMC6191305 DOI: 10.1093/dnares/dsy024] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2017] [Accepted: 06/28/2018] [Indexed: 12/30/2022] Open
Abstract
Seriola quinqueradiata (yellowtail) is the most widely farmed and economically important fish in aquaculture in Japan. In this study, we used the genome of haploid yellowtail fish larvae for de novo assembly of whole-genome sequences, and built a high-quality draft genome for the yellowtail. The total length of the assembled sequences was 627.3 Mb, consisting of 1,394 scaffold sequences (>2 kb) with an N50 length of 1.43 Mb. A total of 27,693 protein-coding genes were predicted for the draft genome, and among these, 25,832 predicted genes (93.3%) were functionally annotated. Given our lack of knowledge of the yellowtail digestive system, and using the annotated draft genome as a reference, we conducted an RNA-Seq analysis of its three digestive organs (stomach, intestine and rectum). The RNA-Seq results highlighted the importance of certain genes in encoding proteolytic enzymes necessary for digestion and absorption in the yellowtail gastrointestinal tract, and this finding will accelerate development of formulated feeds for this species. Since this study offers comprehensive annotation of predicted protein-coding genes, it has potential broad application to our understanding of yellowtail biology and aquaculture.
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Affiliation(s)
- Motoshige Yasuike
- Research Center for Bioinformatics and Biosciences, National Research Institute of Fisheries Science, Japan Fisheries Research and Education Agency, Yokohama, Kanagawa, Japan
| | - Yuki Iwasaki
- Research Center for Bioinformatics and Biosciences, National Research Institute of Fisheries Science, Japan Fisheries Research and Education Agency, Yokohama, Kanagawa, Japan
| | - Issei Nishiki
- Research Center for Bioinformatics and Biosciences, National Research Institute of Fisheries Science, Japan Fisheries Research and Education Agency, Yokohama, Kanagawa, Japan
| | - Yoji Nakamura
- Research Center for Bioinformatics and Biosciences, National Research Institute of Fisheries Science, Japan Fisheries Research and Education Agency, Yokohama, Kanagawa, Japan
| | - Aiko Matsuura
- Research Center for Bioinformatics and Biosciences, National Research Institute of Fisheries Science, Japan Fisheries Research and Education Agency, Yokohama, Kanagawa, Japan
| | - Kazunori Yoshida
- Goto Laboratory, Stock Enhancement and Aquaculture Division, Seikai National Fisheries Research Institute Japan Fisheries Research and Education Agency, Tamanoura-cho, Goto, Nagasaki, Japan
| | - Tsutomu Noda
- Goto Laboratory, Stock Enhancement and Aquaculture Division, Seikai National Fisheries Research Institute Japan Fisheries Research and Education Agency, Tamanoura-cho, Goto, Nagasaki, Japan
| | - Tadashi Andoh
- Stock Enhancement and Aquaculture Division, Seikai National Fisheries Research Institute, Japan Fisheries Research and Education Agency, Nagasaki, Japan
| | - Atushi Fujiwara
- Research Center for Bioinformatics and Biosciences, National Research Institute of Fisheries Science, Japan Fisheries Research and Education Agency, Yokohama, Kanagawa, Japan
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83
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Talks BJ, Bradwell SB, Delamere J, Rayner W, Clarke A, Lewis CT, Thomas OD, Bradwell AR. Urinary Alpha-1-Acid Glycoprotein Is a Sensitive Marker of Glomerular Protein Leakage at Altitude. High Alt Med Biol 2018; 19:295-298. [PMID: 29889556 PMCID: PMC6157339 DOI: 10.1089/ham.2018.0017] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2018] [Accepted: 04/18/2018] [Indexed: 11/13/2022] Open
Abstract
Talks, Ben J., Susie B. Bradwell, John Delamere, Will Rayner, Alex Clarke, Chris T. Lewis, Owen D. Thomas, and Arthur R. Bradwell. Urinary alpha-1-acid glycoprotein is a sensitive marker of glomerular protein leakage at altitude. High Alt Med Biol. 19:295-298, 2018.-Proteinuria is an established feature of ascent to altitude and may be caused by a loss of negative charges on glomerular capillary walls (GCWs). To test this hypothesis, we measured two similar sized but oppositely charged proteins in urine: negatively charged alpha-1-acid glycoprotein (α1-AGP, 41-43 kDa) and positively charged dimeric lambda free light chains (λ-FLCs, 50 kDa). Twenty-four-hour urinary leakage was compared with albumin, a 66 kDa negatively charged protein. We studied 23 individuals (ages 23-78 years, male = 17) at baseline (140 m) and daily during an expedition to 5035 m. The results showed a significant increase in median urinary leakage of α1-AGP (p < 0.0001; 6.85-fold) and albumin (p = 0.0006; 1.65-fold) with ascent to altitude, but no significant increase in leakage of λ-FLCs (p = 0.39; 1.14-fold). α1-AGP correlated with the daily ascent profile (p = 0.0026) and partial pressure of oxygen (p = 0.01), whereas albumin showed no correlation (p = 0.19). Urinary α1-AGP was a more sensitive marker of altitude proteinuria than urinary albumin and λ-FLCs, and supported the possibility of loss of GCW negative charges at altitude.
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Affiliation(s)
- Ben J. Talks
- Medical School, College of Medical and Dental Sciences, University of Birmingham, Birmingham, United Kingdom
- Birmingham Medical Research Expeditionary Society, Birmingham, United Kingdom
| | - Susie B. Bradwell
- Birmingham Medical Research Expeditionary Society, Birmingham, United Kingdom
- East Surrey Hospital Redhill, Surrey, United Kingdom
| | - John Delamere
- Medical School, College of Medical and Dental Sciences, University of Birmingham, Birmingham, United Kingdom
- Birmingham Medical Research Expeditionary Society, Birmingham, United Kingdom
| | - Will Rayner
- The Binding Site Group Ltd., Birmingham, United Kingdom
| | - Alex Clarke
- Birmingham Medical Research Expeditionary Society, Birmingham, United Kingdom
- Newcastle Upon Tyne Hospitals NHS Foundation Trust, Newcastle Upon Tyne, United Kingdom
| | - Chris T. Lewis
- Birmingham Medical Research Expeditionary Society, Birmingham, United Kingdom
- Raigmore Hospital, Inverness, Highland, United Kingdom
| | - Owen D. Thomas
- Birmingham Medical Research Expeditionary Society, Birmingham, United Kingdom
- Taunton and Somerset NHS Foundation Trust, Taunton, United Kingdom
| | - Arthur R. Bradwell
- Medical School, College of Medical and Dental Sciences, University of Birmingham, Birmingham, United Kingdom
- Birmingham Medical Research Expeditionary Society, Birmingham, United Kingdom
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84
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Liu C, Hu Y, Lin J, Fu H, Lim LY, Yuan Z. Targeting strategies for drug delivery to the kidney: From renal glomeruli to tubules. Med Res Rev 2018; 39:561-578. [DOI: 10.1002/med.21532] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2018] [Revised: 07/10/2018] [Accepted: 07/18/2018] [Indexed: 12/22/2022]
Affiliation(s)
- Chun‐Ping Liu
- Department of PharmacyCollege of Veterinary Medicine, Sichuan Agricultural UniversityChengdu China
- Key Laboratory of Animal Disease and Human Health of Sichuan ProvinceChengdu China
| | - You Hu
- Department of PharmacyCollege of Veterinary Medicine, Sichuan Agricultural UniversityChengdu China
- Key Laboratory of Animal Disease and Human Health of Sichuan ProvinceChengdu China
| | - Ju‐Chun Lin
- Department of PharmacyCollege of Veterinary Medicine, Sichuan Agricultural UniversityChengdu China
- Key Laboratory of Animal Disease and Human Health of Sichuan ProvinceChengdu China
| | - Hua‐Lin Fu
- Department of PharmacyCollege of Veterinary Medicine, Sichuan Agricultural UniversityChengdu China
- Key Laboratory of Animal Disease and Human Health of Sichuan ProvinceChengdu China
| | - Lee Yong Lim
- Pharmacy, Centre for Optimization of Medicines, School of Allied Health, The University of Western AustraliaCrawley Australia
| | - Zhi‐Xiang Yuan
- Department of PharmacyCollege of Veterinary Medicine, Sichuan Agricultural UniversityChengdu China
- Key Laboratory of Animal Disease and Human Health of Sichuan ProvinceChengdu China
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85
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Otterpohl KL, Hart RG, Evans C, Surendran K, Chandrasekar I. Nonmuscle myosin 2 proteins encoded by Myh9, Myh10, and Myh14 are uniquely distributed in the tubular segments of murine kidney. Physiol Rep 2018; 5. [PMID: 29208685 PMCID: PMC5727274 DOI: 10.14814/phy2.13513] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2017] [Revised: 10/27/2017] [Accepted: 10/30/2017] [Indexed: 11/24/2022] Open
Abstract
The diverse epithelial cell types of the kidneys are segregated into nephron segments and the collecting ducts in order to endow each tubular segment with unique functions. The rich diversity of the epithelial cell types is highlighted by the unique membrane channels and receptors expressed within each nephron segment. Our previous work identified a critical role for Myh9 and Myh10 in mammalian endocytosis. Here, we examined the expression patterns of Nonmuscle myosin 2 (NM2) heavy chains encoded by Myh9, Myh10, and Myh14 in mouse kidneys as these genes may confer unique nephron segment‐specific membrane transport properties. Interestingly, we found that each segment of the renal tubules predominately expressed only two of the three NM2 isoforms, with isoform‐specific subcellular localization, and different levels of expression within a nephron segment. Additionally, we identify Myh14 to be restricted to the intercalated cells and Myh10 to be restricted to the principal cells within the collecting ducts and connecting segments. We speculate that the distinct expression pattern of the NM2 proteins likely reflects the diversity of the intracellular trafficking machinery present within the different renal tubular epithelial segments.
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Affiliation(s)
- Karla L Otterpohl
- Enabling Technologies Group - Sanford Research, Sioux Falls, South Dakota, USA
| | - Ryan G Hart
- Enabling Technologies Group - Sanford Research, Sioux Falls, South Dakota, USA
| | - Claire Evans
- Molecular Pathology Core, Sanford Research, Sioux Falls, South Dakota, USA
| | - Kameswaran Surendran
- Pediatrics and Rare Diseases Group - Sanford Research, Sioux Falls, South Dakota, USA.,Department of Pediatrics, USD Sanford School of Medicine, Sioux Falls, South Dakota, USA
| | - Indra Chandrasekar
- Enabling Technologies Group - Sanford Research, Sioux Falls, South Dakota, USA.,Department of Pediatrics, USD Sanford School of Medicine, Sioux Falls, South Dakota, USA
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86
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Silva-Aguiar RP, Bezerra NCF, Lucena MC, Sirtoli GM, Sudo RT, Zapata-Sudo G, Takiya CM, Pinheiro AAS, Dias WB, Caruso-Neves C. O-GlcNAcylation reduces proximal tubule protein reabsorption and promotes proteinuria in spontaneously hypertensive rats. J Biol Chem 2018; 293:12749-12758. [PMID: 29954945 DOI: 10.1074/jbc.ra118.001746] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2018] [Revised: 06/27/2018] [Indexed: 12/11/2022] Open
Abstract
Hypertensive individuals are at greater risk for developing chronic kidney disease (CKD). Reducing proteinuria has been suggested as a possible therapeutic approach to treat CKD. However, the mechanisms underlying the development of proteinuria in hypertensive conditions are incompletely understood. Cardiac and vascular dysfunction is associated with changes in the O-GlcNAcylation pathway in hypertensive models. We hypothesized that O-GlcNAcylation is also involved in renal damage, especially development of proteinuria, associated with hypertension. Using the spontaneously hypertensive rat (SHR) model, we observed higher renal cortex O-GlcNAcylation, glutamine-fructose aminotransferase (GFAT), and O-GlcNAc transferase (OGT) protein expression, which positively correlated with proteinuria. Interestingly, this was observed in hypertensive, but not pre-hypertensive, rats. Pharmacological inhibition of GFAT decreased renal cortex O-GlcNAcylation, proteinuria, and albuminuria in SHR. Using a proximal tubule cell line, we observed that increased O-GlcNAcylation reduced megalin surface expression and albumin endocytosis in vitro, and the effects were correlated in vivo Moreover, megalin is O-GlcNAcylated both in vitro and in vivo In conclusion, our results demonstrate a new mechanism involved in hypertension-associated proteinuria.
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Affiliation(s)
- Rodrigo Pacheco Silva-Aguiar
- Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21949-900, Brazil
| | - Nathália C F Bezerra
- Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21949-900, Brazil
| | - Miguel C Lucena
- Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21949-900, Brazil
| | - Gabriela M Sirtoli
- Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21949-900, Brazil
| | - Roberto T Sudo
- Programa de Desenvolvimento de Fármacos, Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21941-902, Brazil
| | - Gisele Zapata-Sudo
- Programa de Desenvolvimento de Fármacos, Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21941-902, Brazil
| | - Christina M Takiya
- Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21949-900, Brazil
| | - Ana Acacia S Pinheiro
- Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21949-900, Brazil
| | - Wagner Barbosa Dias
- Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21949-900, Brazil
| | - Celso Caruso-Neves
- Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21949-900, Brazil; Instituto Nacional de Ciência e Tecnologia em Medicina Regenerativa (INCT-Regenera), Rio de Janeiro 21941-902, Brazil.
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87
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Bryniarski MA, Yee BM, Jaffri I, Chaves LD, Yu JA, Guan X, Ghavam N, Yacoub R, Morris ME. Increased megalin expression in early type 2 diabetes: role of insulin-signaling pathways. Am J Physiol Renal Physiol 2018; 315:F1191-F1207. [PMID: 29949391 DOI: 10.1152/ajprenal.00210.2018] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
The megalin/cubilin complex is responsible for the majority of serum protein reclamation in the proximal tubules. The current study examined if decreases in their renal expression, along with the albumin recycling protein neonatal Fc receptor (FcRn) could account for proteinuria/albuminuria in the Zucker diabetic fatty rat model of type 2 diabetes. Immunoblots of renal cortex samples obtained at worsening disease stages demonstrated no loss in megalin, cubilin, or FcRn, even when proteinuria was measured. Additionally, early diabetic rats exhibited significantly increased renal megalin expression when compared with controls (adjusted P < 0.01). Based on these results, the ability of insulin to increase megalin was examined in a clonal subpopulation of the opossum kidney proximal tubule cell line. Insulin treatments (24 h, 100 nM) under high glucose conditions significantly increased megalin protein ( P < 0.0001), mRNA ( P < 0.0001), and albumin endocytosis. The effect on megalin expression was prevented with inhibitors against key effectors of insulin intracellular signaling, phosphatidylinositide 3-kinase and Akt. Studies using rapamycin to inhibit the mechanistic target of rapamycin complex 1 (mTORC1) resulted in a loss of insulin-induced megalin expression. However, subsequent evaluation demonstrated these effects were independent of initial mTORC1 suppression. The presented results provide insight into the expression of megalin, cubilin, and FcRn in type 2 diabetes, which may be impacted by elevated insulin and glucose. Furthermore, proximal tubule endocytic activity in early diabetics may be enhanced, a process that could have a significant role in proteinuria-induced renal damage.
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Affiliation(s)
- Mark A Bryniarski
- Department of Pharmaceutical Sciences, School of Pharmacy and Pharmaceutical Sciences, University at Buffalo , New York
| | - Benjamin M Yee
- Department of Pharmaceutical Sciences, School of Pharmacy and Pharmaceutical Sciences, University at Buffalo , New York
| | - Irum Jaffri
- Department of Pharmaceutical Sciences, School of Pharmacy and Pharmaceutical Sciences, University at Buffalo , New York
| | - Lee D Chaves
- Department of Internal Medicine, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo , New York
| | - Jin Ah Yu
- Department of Pharmaceutical Sciences, School of Pharmacy and Pharmaceutical Sciences, University at Buffalo , New York
| | - Xiaowen Guan
- Department of Pharmaceutical Sciences, School of Pharmacy and Pharmaceutical Sciences, University at Buffalo , New York
| | - Nazanin Ghavam
- Department of Pharmaceutical Sciences, School of Pharmacy and Pharmaceutical Sciences, University at Buffalo , New York
| | - Rabi Yacoub
- Department of Internal Medicine, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo , New York
| | - Marilyn E Morris
- Department of Pharmaceutical Sciences, School of Pharmacy and Pharmaceutical Sciences, University at Buffalo , New York
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88
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Dabrowski M, Bukowy-Bieryllo Z, Zietkiewicz E. Advances in therapeutic use of a drug-stimulated translational readthrough of premature termination codons. Mol Med 2018; 24:25. [PMID: 30134808 PMCID: PMC6016875 DOI: 10.1186/s10020-018-0024-7] [Citation(s) in RCA: 99] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2018] [Accepted: 05/01/2018] [Indexed: 12/31/2022] Open
Abstract
Premature termination codons (PTCs) in the coding regions of mRNA lead to the incorrect termination of translation and generation of non-functional, truncated proteins. Translational readthrough of PTCs induced by pharmaceutical compounds is a promising way of restoring functional protein expression and reducing disease symptoms, without affecting the genome or transcriptome of the patient. While in some cases proven effective, the clinical use of readthrough-inducing compounds is still associated with many risks and difficulties. This review focuses on problems directly associated with compounds used to stimulate PTC readthrough, such as their interactions with the cell and organism, their toxicity and bioavailability (cell permeability; tissue deposition etc.). Various strategies designed to overcome these problems are presented.
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Affiliation(s)
- Maciej Dabrowski
- Institute of Human Genetics; Polish Academy of Sciences, Poznan, Poland
| | | | - Ewa Zietkiewicz
- Institute of Human Genetics; Polish Academy of Sciences, Poznan, Poland.
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89
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Streng AS, van der Linden N, Kocken JMM, Bekers O, Bouwman FG, Mariman ECM, Meex SJR, Wodzig WKWH, de Boer D. Mass Spectrometric Identification of Cardiac Troponin T in Urine of Patients Suffering from Acute Myocardial Infarction. J Appl Lab Med 2018; 2:857-867. [PMID: 33636816 DOI: 10.1373/jalm.2017.024224] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2017] [Accepted: 08/30/2017] [Indexed: 11/06/2022]
Abstract
BACKGROUND Because of its high cardiospecificity, cardiac troponin T (cTnT) is one of the first-choice biomarkers to diagnose acute myocardial infarction (AMI). cTnT is extensively fragmented in serum of patients suffering from AMI. However, it is currently unknown whether all cTnT is completely degraded in the body or whether some cTnT fragments can leave the body via urine. The aim of the present study is to develop a method for the detection of cTnT in urine and to examine whether cTnT is detectable in patient urine. METHODS Proteins in urine samples of 20 patients were precipitated using a cTnT-specific immunoprecipitation technique and a nonspecific acetonitrile protein precipitation. After in-solution digestion of the precipitated proteins, the resulting peptides were separated and analyzed using HPLC and mass spectrometry with a targeted selected ion monitoring assay with data-dependent tandem mass spectrometry (t-SIM/dd-MS2). RESULTS The t-SIM/dd-MS2 assay was validated using a synthetic peptide standard containing 10 specific cTnT peptides of interest and with purified human intact cTnT spiked in urine from healthy individuals. Using this assay, 6 different cTnT-specific peptides were identified in urine samples from 3 different patients, all suffering from AMI. CONCLUSIONS We show here for the first time that cTnT can be present in the urine of AMI patients using a targeted LC-MS/MS assay. Whether the presence of cTnT in urine reflects a physiological or pathophysiological process still needs to be elucidated.
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Affiliation(s)
- Alexander S Streng
- Department of Clinical Chemistry, Central Diagnostic Laboratory, Maastricht University Medical Center, Maastricht, the Netherlands
| | - Noreen van der Linden
- Department of Clinical Chemistry, Central Diagnostic Laboratory, Maastricht University Medical Center, Maastricht, the Netherlands
| | - Jordy M M Kocken
- Department of Clinical Chemistry, Central Diagnostic Laboratory, Maastricht University Medical Center, Maastricht, the Netherlands
| | - Otto Bekers
- Department of Clinical Chemistry, Central Diagnostic Laboratory, Maastricht University Medical Center, Maastricht, the Netherlands
| | - Freek G Bouwman
- Department of Human Biology, Maastricht University, Maastricht, the Netherlands
| | - Edwin C M Mariman
- Department of Human Biology, Maastricht University, Maastricht, the Netherlands
| | - Steven J R Meex
- Department of Clinical Chemistry, Central Diagnostic Laboratory, Maastricht University Medical Center, Maastricht, the Netherlands
| | - Will K W H Wodzig
- Department of Clinical Chemistry, Central Diagnostic Laboratory, Maastricht University Medical Center, Maastricht, the Netherlands
| | - Douwe de Boer
- Department of Clinical Chemistry, Central Diagnostic Laboratory, Maastricht University Medical Center, Maastricht, the Netherlands
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90
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Heo JY, Kim JE, Dan Y, Kim YW, Kim JY, Cho KH, Bae YK, Im SS, Liu KH, Song IH, Kim JR, Lee IK, Park SY. Clusterin deficiency induces lipid accumulation and tissue damage in kidney. J Endocrinol 2018; 237:175-191. [PMID: 29563234 DOI: 10.1530/joe-17-0453] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/08/2018] [Accepted: 03/21/2018] [Indexed: 01/15/2023]
Abstract
Clusterin is a secretory glycoprotein that is involved in multiple physiopathological processes, including lipid metabolism. Previous studies have shown that clusterin prevents hepatic lipid accumulation via suppression of sterol regulatory element-binding protein (SREBP) 1. In this study, we examined the role of clusterin in renal lipid accumulation in clusterin-knockout mice and NRK52e tubular epithelial cells. Clusterin deficiency increased the expression of SREBP1 and its target genes and decreased malonyl-CoA decarboxylase protein levels in the kidney. Expression of the endocytic receptor, megalin, and scavenger receptor class A was increased in clusterin-deficient mice. Functional analysis of lipid metabolism also revealed that lipid uptake and triglyceride synthesis were increased and fatty acid oxidation was reduced, leading to increased lipid accumulation in clusterin-deficient mice. These phenomena were accompanied by mesangial expansion, fibrosis and increased urinary protein-to-creatinine ratio. High-fat feeding aggravated these clusterin deficiency-induced pathological changes. Clusterin knockdown in NRK52e cells increased lipogenic gene expression and lipid levels, whereas overexpression of clusterin by treatment with adenovirus or recombinant clusterin protein suppressed lipogenic gene expression and lipid levels. Transforming growth factor-beta 1 (TGFB1) expression increased in the kidney of clusterin-deficient mice and suppression of TGFB1 in NRK52e cells suppressed lipid accumulation. These results suggest that clusterin deficiency induces renal lipid accumulation by dysregulating the expression of lipid metabolism-related factors and TGFB1, thereby leading to chronic kidney disease. Hence, clusterin may serve as a therapeutic target for lipid-induced chronic kidney disease.
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Affiliation(s)
- Jung-Yoon Heo
- Department of PhysiologyCollege of Medicine, Yeungnam University, Daegu, Korea
- Smart-Aging Convergence Research CenterCollege of Medicine, Yeungnam University, Daegu, Korea
| | - Ji-Eun Kim
- Department of PhysiologyCollege of Medicine, Yeungnam University, Daegu, Korea
- Smart-Aging Convergence Research CenterCollege of Medicine, Yeungnam University, Daegu, Korea
| | - Yongwook Dan
- Weinberg CollegeNorthwestern University, Evanston, Illinois, USA
| | - Yong-Woon Kim
- Department of PhysiologyCollege of Medicine, Yeungnam University, Daegu, Korea
| | - Jong-Yeon Kim
- Department of PhysiologyCollege of Medicine, Yeungnam University, Daegu, Korea
| | - Kyu Hyang Cho
- Department of Internal MedicineCollege of Medicine, Yeungnam University, Daegu, Korea
| | - Young Kyung Bae
- Department of PathologyCollege of Medicine, Yeungnam University, Daegu, Korea
| | - Seung-Soon Im
- Department of PhysiologyKeimyung University School of Medicine, Daegu, Korea
| | - Kwang-Hyeon Liu
- College of Pharmacy and Research Institute of Pharmaceutical SciencesKyungpook National University, Daegu, Korea
| | - In-Hwan Song
- Department of AnatomyCollege of Medicine, Yeungnam University, Daegu, Korea
| | - Jae-Ryong Kim
- Smart-Aging Convergence Research CenterCollege of Medicine, Yeungnam University, Daegu, Korea
- Department of Biochemistry and Molecular BiologyCollege of Medicine, Yeungnam University, Daegu, Korea
| | - In-Kyu Lee
- Department of Internal MedicineSchool of Medicine, Kyungpook National University, Daegu, Korea
| | - So-Young Park
- Department of PhysiologyCollege of Medicine, Yeungnam University, Daegu, Korea
- Smart-Aging Convergence Research CenterCollege of Medicine, Yeungnam University, Daegu, Korea
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91
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Eriguchi M, Lin M, Yamashita M, Zhao TV, Khan Z, Bernstein EA, Gurley SB, Gonzalez-Villalobos RA, Bernstein KE, Giani JF. Renal tubular ACE-mediated tubular injury is the major contributor to microalbuminuria in early diabetic nephropathy. Am J Physiol Renal Physiol 2018; 314:F531-F542. [PMID: 29187372 PMCID: PMC5966765 DOI: 10.1152/ajprenal.00523.2017] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2017] [Revised: 11/13/2017] [Accepted: 11/28/2017] [Indexed: 12/30/2022] Open
Abstract
Diabetic nephropathy is a major cause of end-stage renal disease in developed countries. While angiotensin-converting enzyme (ACE) inhibitors are used to treat diabetic nephropathy, how intrarenal ACE contributes to diabetic renal injury is uncertain. Here, two mouse models with different patterns of renal ACE expression were studied to determine the specific contribution of tubular vs. glomerular ACE to early diabetic nephropathy: it-ACE mice, which make endothelial ACE but lack ACE expression by renal tubular epithelium, and ACE 3/9 mice, which lack endothelial ACE and only express renal ACE in tubular epithelial cells. The absence of endothelial ACE normalized the glomerular filtration rate and endothelial injury in diabetic ACE 3/9 mice. However, these mice developed tubular injury and albuminuria and displayed low renal levels of megalin that were similar to those observed in diabetic wild-type mice. In diabetic it-ACE mice, despite hyperfiltration, the absence of renal tubular ACE greatly reduced tubulointerstitial injury and albuminuria and increased renal megalin expression compared with diabetic wild-type and diabetic ACE 3/9 mice. These findings demonstrate that endothelial ACE is a central regulator of the glomerular filtration rate while tubular ACE is a key player in the development of tubular injury and albuminuria. These data suggest that tubular injury, rather than hyperfiltration, is the main cause of microalbuminuria in early diabetic nephropathy.
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Affiliation(s)
- Masahiro Eriguchi
- Department of Biomedical Sciences, Cedars-Sinai Medical Center , Los Angeles, California
| | - Mercury Lin
- Departments of Pathology and Laboratory Medicine, Cedars-Sinai Medical Center , Los Angeles, California
| | - Michifumi Yamashita
- Departments of Pathology and Laboratory Medicine, Cedars-Sinai Medical Center , Los Angeles, California
| | - Tuantuan V Zhao
- Department of Biomedical Sciences, Cedars-Sinai Medical Center , Los Angeles, California
| | - Zakir Khan
- Department of Biomedical Sciences, Cedars-Sinai Medical Center , Los Angeles, California
| | - Ellen A Bernstein
- Department of Biomedical Sciences, Cedars-Sinai Medical Center , Los Angeles, California
| | - Susan B Gurley
- Division of Nephrology, Department of Medicine, Duke University School of Medicine , Durham, North Carolina
| | | | - Kenneth E Bernstein
- Department of Biomedical Sciences, Cedars-Sinai Medical Center , Los Angeles, California
- Departments of Pathology and Laboratory Medicine, Cedars-Sinai Medical Center , Los Angeles, California
| | - Jorge F Giani
- Department of Biomedical Sciences, Cedars-Sinai Medical Center , Los Angeles, California
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92
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Glund S, Gan G, Moschetti V, Reilly P, Honickel M, Grottke O, Van Ryn J. The Renal Elimination Pathways of the Dabigatran Reversal Agent Idarucizumab and its Impact on Dabigatran Elimination. Clin Appl Thromb Hemost 2018. [PMID: 29534609 PMCID: PMC6714879 DOI: 10.1177/1076029618755947] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Idarucizumab, a humanized monoclonal antibody fragment (Fab), provides rapid and sustained reversal of dabigatran-mediated anticoagulation. Idarucizumab and dabigatran are mainly eliminated via the kidneys. This analysis aimed to characterize the renal elimination of idarucizumab and investigate the influence of idarucizumab on the pharmacokinetics (PK) of dabigatran and vice versa. Studies were conducted in 5/6 nephrectomized rats, in human volunteers with and without renal impairment, and in a porcine liver trauma model. In both rats and humans, renal impairment increased idarucizumab exposure and initial half-life but did not affect its terminal half-life. Urinary excretion of unchanged idarucizumab increased with increasing idarucizumab dose, suggesting saturation of renal tubular reuptake processes at higher doses. The PK of idarucizumab was unaffected by dabigatran. In contrast, idarucizumab administration resulted in redistribution of dabigatran to the plasma, where it was bound and inactivated by idarucizumab. Urinary excretion of dabigatran after administration of idarucizumab was delayed, but total dabigatran excreted in urine was unaffected. Idarucizumab and dabigatran were eliminated together via renal pathways.
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Affiliation(s)
- Stephan Glund
- 1 Boehringer Ingelheim Pharma GmbH & Co KG, Biberach an der Riß, Germany
| | - Guanfa Gan
- 2 Boehringer Ingelheim Pharmaceuticals, Inc, Ridgefield, CT, USA
| | | | - Paul Reilly
- 2 Boehringer Ingelheim Pharmaceuticals, Inc, Ridgefield, CT, USA
| | - Markus Honickel
- 4 Department of Anaesthesiology, RWTH Aachen University Hospital, Aachen, Germany
| | - Oliver Grottke
- 4 Department of Anaesthesiology, RWTH Aachen University Hospital, Aachen, Germany
| | - Joanne Van Ryn
- 1 Boehringer Ingelheim Pharma GmbH & Co KG, Biberach an der Riß, Germany
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93
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Kokoris SI, Gavriilaki E, Miari A, Travlou Α, Kyriakou E, Anagnostopoulos A, Grouzi E. Renal involvement in paroxysmal nocturnal hemoglobinuria: an update on clinical features, pathophysiology and treatment. ACTA ACUST UNITED AC 2018; 23:558-566. [PMID: 29486674 DOI: 10.1080/10245332.2018.1444563] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
OBJECTIVES The present review summarizes the available knowledge regarding acute and chronic kidney dysfunction in patients with paroxysmal nocturnal hemoglobinuria (PNH) focusing on its clinical features, pathophysiology and treatment. METHODS A thorough PubMed search was performed using as main keywords: 'paroxysmal nocturnal hemoglobinuria', 'acute kidney injury', 'chronic kidney disease' and 'eculizumab'. RESULTS PNH's etiopathogenesis is based on acquired mutations that lead to the reduction or absence of CD55 and CD59 complement regulators, which are responsible for some of the disease's major clinical features, like intravascular hemolysis, cytopenias and thrombosis. PNH is often underdiagnosed, mainly due to its occasional mild manifestations and to its ability to mimic other severe clinical conditions. Various mechanisms have been proposed for the kidney damage attributed to the release of cell-free heme and free iron, including inflammatory response, oxidative stress, nitric oxide depletion, renal ischemia, membrane damage and apoptosis. Eculizumab, a terminal complement inhibitor, provides a safe and effective treatment option, especially when it is initiated early in the presence of kidney damage. DISCUSSION Kidney injury is a poorly investigated clinical feature of PNH that affects a significant portion of patients. Increased awareness is needed by physicians to recognize the early signs and symptoms of acute and chronic renal insufficiency, so as to initiate the necessary therapy. It is also important to re-evaluation of PNH-specific treatments during the course of the disease. CONCLUSION Understanding the difficult but at the same time impressive mechanisms behind PNH remains a challenge for treating physicians.
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Affiliation(s)
- Styliani I Kokoris
- a Laboratory of Hematology and Hospital Blood Transfusion Department , University General Hospital 'Attikon', Medical School, National and Kapodistrian University of Athens , Chaidari Attica , Greece
| | - Eleni Gavriilaki
- b Hematology Department-BMT Unit , G. Papanicolaou Hospital , Thessaloniki , Greece
| | - Aggeliki Miari
- c Medical School , University of Athens , Athens , Greece
| | - Αnthi Travlou
- c Medical School , University of Athens , Athens , Greece.,d Laboratory of Thrombosis, Bleeding Disorders and Anticoagulation Monitoring , Medical Centre of Psychico , Athens , Greece
| | - Elias Kyriakou
- a Laboratory of Hematology and Hospital Blood Transfusion Department , University General Hospital 'Attikon', Medical School, National and Kapodistrian University of Athens , Chaidari Attica , Greece
| | | | - Elissavet Grouzi
- e Department of Transfusion Service and Clinical Hemostasis , 'Saint Savvas' Oncology Hospital , Athens , Greece
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94
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Sirac C, Herrera GA, Sanders PW, Batuman V, Bender S, Ayala MV, Javaugue V, Teng J, Turbat-Herrera EA, Cogné M, Touchard G, Leung N, Bridoux F. Animal models of monoclonal immunoglobulin-related renal diseases. Nat Rev Nephrol 2018; 14:246-264. [DOI: 10.1038/nrneph.2018.8] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
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95
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Decreased expression of megalin and cubilin and altered mitochondrial activity in tenofovir nephrotoxicity. Hum Pathol 2018; 73:89-101. [PMID: 29309806 DOI: 10.1016/j.humpath.2017.12.018] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/08/2017] [Revised: 12/06/2017] [Accepted: 12/16/2017] [Indexed: 11/20/2022]
Abstract
Tenofovir disoproxil fumarate (TDF) is a commonly used antiretroviral drug for HIV, rarely causing Fanconi syndrome and acute kidney injury. We retrospectively analyzed the clinico pathological presentation of 20 cases of tenofovir-induced tubulopathy, and investigated the renal expression of the megalin and cubilin proteins, as well as the mitochondrial respiratory chain activity. Estimated glomerular filtration rate (eGFR) before TDF exposure was 92 ml/min/1.73m2, decreasing to 27.5 ml/min/1.73m2 at the time of biopsy, with 30% of patients requiring renal replacement therapy. Proximal tubular expression of megalin and cubilin was altered in 19 and 18 cases, respectively, whereas it was preserved in patients exposed to TDF without proximal tubular dysfunction and in HIV-negative patients with acute tubular necrosis. Loss of megalin/cubilin was correlated with low eGFR and high urine retinol binding protein at the time of biopsy, low eGFR at last follow-up, and was more severe in patients with multifactorial toxicity. Patients with additional nephrotoxic conditions promoting tenofovir accumulation showed a lower eGFR at presentation and at last follow-up, and more severe lesions of acute tubular necrosis, than those with isolated tenofovir toxicity. Altered mitochondrial COX activity in proximal tubules was observed and may be an early cellular alteration in tenofovir nephrotoxicity. In conclusion, altered megalin/cubilin expression represents a distinctive feature in tenofovir-induced tubulopathy, and its severity is correlated with urine retinol binding protein loss and is associated with a poor renal prognosis. Concomitant exposure to other nephrotoxic conditions severely impacts the renal presentation and outcome.
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96
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Elshaer SS, Anwar HM. Relevance of megalin receptor injury with nuclear factor-kappa B upregulation in acute kidney injury induced in rats. J Biochem Mol Toxicol 2017; 32. [PMID: 29286200 DOI: 10.1002/jbt.22014] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2017] [Revised: 11/04/2017] [Accepted: 11/20/2017] [Indexed: 12/22/2022]
Abstract
Proximal tubule protein take-up is interceded by 2 receptors, megalin and cubilin. These receptors rescue an assortment of filtered ligands including fundamental vitamins and hormones. The objective of this study was to investigate the potential relation of megalin receptor injury with nuclear factor-kappa B (NF-κB) upregulation in acute kidney injury rat model. Twenty four rats were allocated into two groups: control group received saline, while the second group was intoxicated with cadmium chloride (2.4 mg Cd/kg/day i.p) for 30 days. Blood urea nitrogen, serum creatinine, tissue oxidant-antioxidant parameters (malondialdehyde [MDA] and reduced glutathione [GSH]) and expression levels for NF-κB, toll like receptor-2 (TLR2), toll like receptor-4 (TLR4), and megalin receptor were estimated. Noticeable downregulation of megalin receptor versus upregulation of NF-κB, TLR2, and TLR4 were observed in AKI rat model together with significant elevation in MDA as well as significant reduction in GSH. The study concluded that the oxidative stress in kidney tissue leads to megalin receptor damage, which indeed motivates upregulation of NF-κB through TLRs 2 and 4 pathways.
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Affiliation(s)
- Shereen Saeid Elshaer
- Department of Biochemistry, Pharmacy Faculty for Girls, Al-Azhar University, Cairo, Egypt
| | - Hend Mohamed Anwar
- Department of Biochemistry, National Organization for Drug Control and Research (NODCAR), Giza, Egypt
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97
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Valentijn FA, Falke LL, Nguyen TQ, Goldschmeding R. Cellular senescence in the aging and diseased kidney. J Cell Commun Signal 2017; 12:69-82. [PMID: 29260442 PMCID: PMC5842195 DOI: 10.1007/s12079-017-0434-2] [Citation(s) in RCA: 98] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2017] [Accepted: 11/03/2017] [Indexed: 12/19/2022] Open
Abstract
The program of cellular senescence is involved in both the G1 and G2 phase of the cell cycle, limiting G1/S and G2/M progression respectively, and resulting in prolonged cell cycle arrest. Cellular senescence is involved in normal wound healing. However, multiple organs display increased senescent cell numbers both during natural aging and after injury, suggesting that senescent cells can have beneficial as well as detrimental effects in organismal aging and disease. Also in the kidney, senescent cells accumulate in various compartments with advancing age and renal disease. In experimental studies, forced apoptosis induction through the clearance of senescent cells leads to better preservation of kidney function during aging. Recent groundbreaking studies demonstrate that senescent cell depletion through INK-ATTAC transgene-mediated or cell-penetrating FOXO4-DRI peptide induced forced apoptosis, reduced age-associated damage and dysfunction in multiple organs, in particular the kidney, and increased performance and lifespan. Senescence is also involved in oncology and therapeutic depletion of senescent cells by senolytic drugs has been studied in experimental and human cancers. Although studies with senolytic drugs in models of kidney injury are lacking, their dose limiting side effects on other organs suggest that targeted delivery might be needed for successful application of senolytic drugs for treatment of kidney disease. In this review, we discuss (i) current understanding of the mechanisms and associated pathways of senescence, (ii) evidence of senescence occurrence and causality with organ injury, and (iii) therapeutic strategies for senescence depletion (senotherapy) including targeting, all in the context of renal aging and disease.
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Affiliation(s)
- F A Valentijn
- Department of Pathology, University Medical Center Utrecht, H04.312, Heidelberglaan 110, 3584, CX, Utrecht, The Netherlands
| | - L L Falke
- Department of Pathology, University Medical Center Utrecht, H04.312, Heidelberglaan 110, 3584, CX, Utrecht, The Netherlands
- Department of Internal Medicine, Diakonessenhuis, Utrecht, The Netherlands
| | - T Q Nguyen
- Department of Pathology, University Medical Center Utrecht, H04.312, Heidelberglaan 110, 3584, CX, Utrecht, The Netherlands
| | - Roel Goldschmeding
- Department of Pathology, University Medical Center Utrecht, H04.312, Heidelberglaan 110, 3584, CX, Utrecht, The Netherlands.
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98
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Zeng B, Chen GL, Garcia-Vaz E, Bhandari S, Daskoulidou N, Berglund LM, Jiang H, Hallett T, Zhou LP, Huang L, Xu ZH, Nair V, Nelson RG, Ju W, Kretzler M, Atkin SL, Gomez MF, Xu SZ. ORAI channels are critical for receptor-mediated endocytosis of albumin. Nat Commun 2017; 8:1920. [PMID: 29203863 PMCID: PMC5714946 DOI: 10.1038/s41467-017-02094-y] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2016] [Accepted: 11/06/2017] [Indexed: 01/15/2023] Open
Abstract
Impaired albumin reabsorption by proximal tubular epithelial cells (PTECs) has been highlighted in diabetic nephropathy (DN), but little is known about the underlying molecular mechanisms. Here we find that ORAI1-3, are preferentially expressed in PTECs and downregulated in patients with DN. Hyperglycemia or blockade of insulin signaling reduces the expression of ORAI1-3. Inhibition of ORAI channels by BTP2 and diethylstilbestrol or silencing of ORAI expression impairs albumin uptake. Transgenic mice expressing a dominant-negative Orai1 mutant (E108Q) increases albuminuria, and in vivo injection of BTP2 exacerbates albuminuria in streptozotocin-induced and Akita diabetic mice. The albumin endocytosis is Ca2+-dependent and accompanied by ORAI1 internalization. Amnionless (AMN) associates with ORAIs and forms STIM/ORAI/AMN complexes after Ca2+ store depletion. STIM1/ORAI1 colocalizes with clathrin, but not with caveolin, at the apical membrane of PTECs, which determines clathrin-mediated endocytosis. These findings provide insights into the mechanisms of protein reabsorption and potential targets for treating diabetic proteinuria. Patients with diabetic nephropathy suffer from impaired albumin reabsorption by proximal tubular epithelial cells. Here authors use diabetic and transgenic mouse models and in vitro models to show the cause for this lies in the down regulation and internalization of the ion channels, ORAI1-3.
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Affiliation(s)
- Bo Zeng
- Centre for Cardiovascular and Metabolic Research, Hull York Medical School, University of Hull, Hull, HU6 7RX, UK. .,Key Laboratory of Medical Electrophysiology, Ministry of Education, and Institute of Cardiovascular Research, Southwest Medical University, Luzhou, 646000, China.
| | - Gui-Lan Chen
- Centre for Cardiovascular and Metabolic Research, Hull York Medical School, University of Hull, Hull, HU6 7RX, UK.,Key Laboratory of Medical Electrophysiology, Ministry of Education, and Institute of Cardiovascular Research, Southwest Medical University, Luzhou, 646000, China
| | - Eliana Garcia-Vaz
- Department of Clinical Sciences in Malmö, Lund University Diabetes Centre, Lund University, Malmö, 214 28 Malmö, Sweden
| | - Sunil Bhandari
- Department of Renal Medicine and Hull York Medical School, Hull Royal Infirmary, Hull and East Yorkshire Hospitals NHS Trust, Hull, HU3 2JZ, UK
| | - Nikoleta Daskoulidou
- Centre for Cardiovascular and Metabolic Research, Hull York Medical School, University of Hull, Hull, HU6 7RX, UK
| | - Lisa M Berglund
- Department of Clinical Sciences in Malmö, Lund University Diabetes Centre, Lund University, Malmö, 214 28 Malmö, Sweden
| | - Hongni Jiang
- Centre for Cardiovascular and Metabolic Research, Hull York Medical School, University of Hull, Hull, HU6 7RX, UK
| | - Thomas Hallett
- Centre for Cardiovascular and Metabolic Research, Hull York Medical School, University of Hull, Hull, HU6 7RX, UK
| | - Lu-Ping Zhou
- Key Laboratory of Medical Electrophysiology, Ministry of Education, and Institute of Cardiovascular Research, Southwest Medical University, Luzhou, 646000, China
| | - Li Huang
- Key Laboratory of Medical Electrophysiology, Ministry of Education, and Institute of Cardiovascular Research, Southwest Medical University, Luzhou, 646000, China
| | - Zi-Hao Xu
- Key Laboratory of Medical Electrophysiology, Ministry of Education, and Institute of Cardiovascular Research, Southwest Medical University, Luzhou, 646000, China
| | - Viji Nair
- Department of Internal Medicine & Department of Computational Medicine and Bioinformatics, University of Michigan, Ann Arbor, MI, 48109, USA
| | - Robert G Nelson
- Chronic Kidney Disease Section, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Phoenix, AZ, 85014, USA
| | - Wenjun Ju
- Department of Internal Medicine & Department of Computational Medicine and Bioinformatics, University of Michigan, Ann Arbor, MI, 48109, USA
| | - Matthias Kretzler
- Department of Internal Medicine & Department of Computational Medicine and Bioinformatics, University of Michigan, Ann Arbor, MI, 48109, USA
| | - Stephen L Atkin
- Centre for Cardiovascular and Metabolic Research, Hull York Medical School, University of Hull, Hull, HU6 7RX, UK.,Weill Cornell Medical College Qatar, PO Box, 24144, Doha, Qatar
| | - Maria F Gomez
- Department of Clinical Sciences in Malmö, Lund University Diabetes Centre, Lund University, Malmö, 214 28 Malmö, Sweden
| | - Shang-Zhong Xu
- Centre for Cardiovascular and Metabolic Research, Hull York Medical School, University of Hull, Hull, HU6 7RX, UK.
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99
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Moschetti V, Norris S, Stangier J, Schmohl M, Ryn JV, Lang B, Ramael S, Reilly P, Glund S. A randomised study in healthy volunteers to investigate the safety, tolerability and pharmacokinetics of idarucizumab, a specific antidote to dabigatran. Thromb Haemost 2017; 113:943-51. [DOI: 10.1160/th14-12-1080] [Citation(s) in RCA: 198] [Impact Index Per Article: 28.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2014] [Accepted: 02/20/2015] [Indexed: 12/16/2022]
Abstract
SummaryIdarucizumab, a monoclonal antibody fragment that binds dabigatran with high affinity, is in development as a specific antidote for dabigatran. In this first-in-human, single-rising-dose study, we investigated the pharmacokinetics, safety and tolerability of idarucizumab. Healthy male volunteers aged 18–45 years received between 20 mg and 8 g idarucizumab as a 1-hour intravenous infusion in 10 sequential dose groups, or 1, 2 or 4 g idarucizumab as a 5-minute infusion. Subjects within each dose group were randomised 3:1 to idarucizumab or placebo. A total of 110 randomised subjects received study drug (27 placebo, 83 idarucizumab). Peak and total exposure to idarucizumab increased proportionally with dose. Maximum plasma concentrations were achieved near the end of infusion, followed by a rapid decline, with an initial idarucizumab half-life of ∼45 minutes. For the 5-minute infusions, this resulted in a reduction of plasma concentrations to less than 5 % of peak within 4 hours. Idarucizumab (in the absence of dabigatran) had no effect on coagulation parameters or endogenous thrombin potential. Overall adverse event (AE) frequency was similar for idarucizumab and placebo, and no relationship with idarucizumab dose was observed. Drug-related AEs (primary endpoint) were rare (occurring in 2 placebo and 3 idarucizumab subjects) and were mostly of mild intensity; none of them resulted in study discontinuation. In conclusion, the pharmacokinetic profile of idarucizumab meets the requirement for rapid peak exposure and rapid elimination, with no effect on pharmacodynamic parameters. Idarucizumab was safe and well tolerated in healthy males.Clinical trial registration: http://clinicaltrials.gov/ct2/show/NCT01688830?term=NCT01688830&rank=1 (NCT01688830).
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100
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Gianesello L, Priante G, Ceol M, Radu CM, Saleem MA, Simioni P, Terrin L, Anglani F, Del Prete D. Albumin uptake in human podocytes: a possible role for the cubilin-amnionless (CUBAM) complex. Sci Rep 2017; 7:13705. [PMID: 29057905 PMCID: PMC5651885 DOI: 10.1038/s41598-017-13789-z] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2017] [Accepted: 10/02/2017] [Indexed: 12/23/2022] Open
Abstract
Albumin re-uptake is a receptor-mediated pathway located in renal proximal tubuli. There is increasing evidence of glomerular protein handling by podocytes, but little is known about the mechanism behind this process. In this study, we found that human podocytes in vitro are committed to internalizing albumin through a receptor-mediated mechanism even after exposure to low doses of albumin. We show that these cells express cubilin, megalin, ClC-5, amnionless and Dab2, which are partners in the tubular machinery. Exposing human podocytes to albumin overload prompted an increase in CUBILIN, AMNIONLESS and CLCN5 gene expression. Inhibiting cubilin led to a reduction in albumin uptake, highlighting its importance in this mechanism. We demonstrated that human podocytes are committed to performing endocytosis via a receptor-mediated mechanism even in the presence of low doses of albumin. We also disclosed that protein overload first acts on the expression of the cubilin-amnionless (CUBAM) complex in these cells, then involves the ClC-5 channel, providing the first evidence for a possible role of the CUBAM complex in albumin endocytosis in human podocytes.
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Affiliation(s)
- Lisa Gianesello
- Clinical Nephrology, Department of Medicine - DIMED, University of Padua, 35129, Padua, Italy
| | - Giovanna Priante
- Clinical Nephrology, Department of Medicine - DIMED, University of Padua, 35129, Padua, Italy
| | - Monica Ceol
- Clinical Nephrology, Department of Medicine - DIMED, University of Padua, 35129, Padua, Italy
| | - Claudia M Radu
- Thrombotic and Hemorrhagic Diseases Unit, Department of Medicine - DIMED, University of Padua, 35129, Padua, Italy
| | - Moin A Saleem
- Academic and Children's Renal Unit, Dorothy Hodgkin Building, BS8 1TH, Bristol, United Kingdom
| | - Paolo Simioni
- Thrombotic and Hemorrhagic Diseases Unit, Department of Medicine - DIMED, University of Padua, 35129, Padua, Italy
| | - Liliana Terrin
- Clinical Nephrology, Department of Medicine - DIMED, University of Padua, 35129, Padua, Italy
| | - Franca Anglani
- Clinical Nephrology, Department of Medicine - DIMED, University of Padua, 35129, Padua, Italy
| | - Dorella Del Prete
- Clinical Nephrology, Department of Medicine - DIMED, University of Padua, 35129, Padua, Italy.
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