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Tanzi A, Buono L, Grange C, Iampietro C, Brossa A, Arcolino FO, Arigoni M, Calogero R, Perin L, Deaglio S, Levtchenko E, Peruzzi L, Bussolati B. Urine-derived podocytes from steroid resistant nephrotic syndrome patients as a model for renal-progenitor derived extracellular vesicles effect and drug screening. J Transl Med 2024; 22:762. [PMID: 39143486 PMCID: PMC11323595 DOI: 10.1186/s12967-024-05575-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2024] [Accepted: 08/04/2024] [Indexed: 08/16/2024] Open
Abstract
BACKGROUND Personalized disease models are crucial for evaluating how diseased cells respond to treatments, especially in case of innovative biological therapeutics. Extracellular vesicles (EVs), nanosized vesicles released by cells for intercellular communication, have gained therapeutic interest due to their ability to reprogram target cells. We here utilized urinary podocytes obtained from children affected by steroid-resistant nephrotic syndrome with characterized genetic mutations as a model to test the therapeutic potential of EVs derived from kidney progenitor cells (nKPCs). METHODS EVs were isolated from nKPCs derived from the urine of a preterm neonate. Three lines of urinary podocytes obtained from nephrotic patients' urine and a line of Alport syndrome patient podocytes were characterized and used to assess albumin permeability in response to nKPC-EVs or various drugs. RNA sequencing was conducted to identify commonly modulated pathways after nKPC-EV treatment. siRNA transfection was used to demonstrate the involvement of SUMO1 and SENP2 in the modulation of permeability. RESULTS Treatment with the nKPC-EVs significantly reduced permeability across all the steroid-resistant patients-derived and Alport syndrome-derived podocytes. At variance, podocytes appeared unresponsive to standard pharmacological treatments, with the exception of one line, in alignment with the patient's clinical response at 48 months. By RNA sequencing, only two genes were commonly upregulated in nKPC-EV-treated genetically altered podocytes: small ubiquitin-related modifier 1 (SUMO1) and Sentrin-specific protease 2 (SENP2). SUMO1 and SENP2 downregulation increased podocyte permeability confirming the role of the SUMOylation pathway. CONCLUSIONS nKPCs emerge as a promising non-invasive source of EVs with potential therapeutic effects on podocytes with genetic dysfunction, through modulation of SUMOylation, an important pathway for the stability of podocyte slit diaphragm proteins. Our findings also suggest the feasibility of developing a non-invasive in vitro model for screening regenerative compounds on patient-derived podocytes.
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Affiliation(s)
- Adele Tanzi
- Department of Molecular Biotechnology and Health Sciences, University of Turin, Via Nizza 52, Turin, 10125, Italy
| | - Lola Buono
- Department of Molecular Biotechnology and Health Sciences, University of Turin, Via Nizza 52, Turin, 10125, Italy
| | - Cristina Grange
- Department of Medical Sciences, University of Turin, Turin, Italy
| | - Corinne Iampietro
- Department of Molecular Biotechnology and Health Sciences, University of Turin, Via Nizza 52, Turin, 10125, Italy
| | - Alessia Brossa
- Department of Molecular Biotechnology and Health Sciences, University of Turin, Via Nizza 52, Turin, 10125, Italy
| | - Fanny Oliveira Arcolino
- Department of Pediatric Nephrology, Emma Children's Hospital, Amsterdam UMC, Amsterdam, The Netherlands
- Emma Centrum of Personalized Medicine, Emma Children's Hospital, Amsterdam UMC, Amsterdam, The Netherlands
| | - Maddalena Arigoni
- Department of Molecular Biotechnology and Health Sciences, University of Turin, Via Nizza 52, Turin, 10125, Italy
| | - Raffaele Calogero
- Department of Molecular Biotechnology and Health Sciences, University of Turin, Via Nizza 52, Turin, 10125, Italy
| | - Laura Perin
- Department of Urology, Children's Hospital Los Angeles, Los Angeles, CA, USA
| | - Silvia Deaglio
- Department of Medical Sciences, University of Turin, Turin, Italy
| | - Elena Levtchenko
- Department of Pediatric Nephrology, Emma Children's Hospital, Amsterdam UMC, Amsterdam, The Netherlands
- Department of Development and Regeneration, Cluster Woman and Child, Laboratory of Pediatric Nephrology, KU Leuven, Leuven, Belgium
| | - Licia Peruzzi
- Pediatric Nephrology, ERKNet Center, Regina Margherita Children's Hospital, AOU Città della, Salute e della Scienza di Torino, Turin, Italy
| | - Benedetta Bussolati
- Department of Molecular Biotechnology and Health Sciences, University of Turin, Via Nizza 52, Turin, 10125, Italy.
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Kruangkum T, Jaiboon K, Pakawanit P, Saetan J, Pudgerd A, Wannapaiboon S, Chotwiwatthanakun C, Cummins SF, Sobhon P, Vanichviriyakit R. Anatomical and molecular insights into the antennal gland of the giant freshwater prawn Macrobrachium rosenbergii. Cell Tissue Res 2024; 397:125-146. [PMID: 38878176 PMCID: PMC11291661 DOI: 10.1007/s00441-024-03898-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2023] [Accepted: 05/07/2024] [Indexed: 08/03/2024]
Abstract
In this study, the complex organization of the AnG in the giant freshwater prawn Macrobrachium rosenbergii was revealed using various techniques, including conventional histology, histochemistry, scanning electron microscopy, and X-ray tomography. The results showed the diversity of cells in the AnG and the detailed organization of the labyrinth's tubule into four radiated areas from the central to peripheral zones. The study also demonstrated the expression of some vertebrate kidney-associated homolog genes, aquaporin (AQP), solute carrier family 22 (SLC-22), nephrin, and uromodulin, in the AnG by qPCR. The result of in situ hybridization further showed the localization of SLC-22 and AQP transcript in the bladder and labyrinth's epithelium, specifically in regions 2, 3, and 4. Additionally, the study revealed neuropeptide expressions in the AnG by qPCR and in situ hybridization, i.e., crustacean hyperglycemic hormone (CHH) and molt inhibiting hormone (MIH), implying that the AnG may have a role in hormone production. Moreover, male and female prawns exhibited different levels of AQP, SLC-22, nephrin, and CHH expressions during the premolt and intermolt stages, suggesting a crucial role relevant to the molting stages. In conclusion, this study clarified the complex structure of the AnG in M. rosenbergii and demonstrated for the first time the expression of vertebrate kidney-associated genes and the possible endocrine role of the AnG. Further investigation is needed to clarify the role of these genes, particularly during ecdysis. The implications of these findings could significantly advance our understanding of the AnG in decapod crustaceans.
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Affiliation(s)
- Thanapong Kruangkum
- Department of Anatomy, Faculty of Science, Mahidol University, Bangkok, 10400, Thailand
- Center of Excellence for Shrimp Molecular Biology and Biotechnology (Centex Shrimp), Faculty of Science, Mahidol University, Rama VI Road, Bangkok, 10400, Thailand
| | - Kornchanok Jaiboon
- Center of Excellence for Shrimp Molecular Biology and Biotechnology (Centex Shrimp), Faculty of Science, Mahidol University, Rama VI Road, Bangkok, 10400, Thailand
| | - Phakkhananan Pakawanit
- Synchrotron Light Research Institute (Public Organization), Nakhon Ratchasima, 30000, Thailand
| | - Jirawat Saetan
- Division of Health and Applied Sciences, Faculty of Science, Prince of Songkla University, Hat Yai, Songkhla, 90112, Thailand
| | - Arnon Pudgerd
- Division of Anatomy, School of Medical Science, University of Phayao, Muang, Phayao, 56000, Thailand
| | - Suttipong Wannapaiboon
- Synchrotron Light Research Institute (Public Organization), Nakhon Ratchasima, 30000, Thailand
| | - Charoonroj Chotwiwatthanakun
- Center of Excellence for Shrimp Molecular Biology and Biotechnology (Centex Shrimp), Faculty of Science, Mahidol University, Rama VI Road, Bangkok, 10400, Thailand
- Mahidol University, Nakhonsawan Campus, Nakhonsawan, 60130, Thailand
| | - Scott F Cummins
- Centre for Bioinnovation, University of the Sunshine Coast, Maroochydore DC, Sippy Downs, QLD, 4558, Australia
- School of Science, Technology and Engineering, University of the Sunshine Coast, Maroochydore DC, Sippy Downs, QLD, 4558, Australia
| | - Prasert Sobhon
- Department of Anatomy, Faculty of Science, Mahidol University, Bangkok, 10400, Thailand
| | - Rapeepun Vanichviriyakit
- Department of Anatomy, Faculty of Science, Mahidol University, Bangkok, 10400, Thailand.
- Center of Excellence for Shrimp Molecular Biology and Biotechnology (Centex Shrimp), Faculty of Science, Mahidol University, Rama VI Road, Bangkok, 10400, Thailand.
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Liu X, Qin H, Liu Y, Ma J, Li Y, He Y, Zhu H, Mao L. The biological functions and pathological mechanisms of CASK in various diseases. Heliyon 2024; 10:e28863. [PMID: 38638974 PMCID: PMC11024568 DOI: 10.1016/j.heliyon.2024.e28863] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2023] [Revised: 03/21/2024] [Accepted: 03/26/2024] [Indexed: 04/20/2024] Open
Abstract
Background As a scaffold protein, calcium/calmodulin-dependent serine protein kinase (CASK) has been extensively studied in a variety of tissues throughout the body. The Cask gene is ubiquitous in several tissues, such as the neurons, islets, heart, kidneys and sperm, and is mostly localised in the cytoplasm adjacent to the basement membrane. CASK binds to a variety of proteins through its domains to exerting its biological activity. Scope of review Here, we discuss the role of CASK in multiple tissues throughout the body. The role of different CASK domains in regulating neuronal development, neurotransmitter release and synaptic vesicle secretion was emphasised; the regulatory mechanism of CASK on the function of pancreatic islet β cells was analysed; the role of CASK in cardiac physiology, kidney and sperm development was discussed; and the role of CASK in different tumours was compared. Finally, we clarify the importance of the Cask gene in the body, and how deletion or mutation of the Cask gene can have adverse consequences. Major conclusions CASK is a conserved gene with similar roles in various tissues. The function of the Cask gene in the nervous system is mainly involved in the development of the nervous system and the release of neurotransmitters. In the endocrine system, an involvement of CASK has been reported in the process of insulin vesicle transport. CASK is also involved in cardiomyocyte ion channel regulation, kidney and sperm development, and tumour proliferation. CASK is an indispensable gene for the whole body, and CASK mutations can cause foetal malformations or death at birth. In this review, we summarise the biological functions and pathological mechanisms of CASK in various systems, thereby providing a basis for further in-depth studies of CASK functions.
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Affiliation(s)
- Xingjing Liu
- Department of Endocrinology, The Affiliated Huaian No.1 People’s Hospital of Nanjing Medical University, Huaian, Jiangsu Province, China
| | - Haonan Qin
- Department of Orthopedics, The Affiliated Huaian No.1 People’s Hospital of Nanjing Medical University, Huaian, Jiangsu Province, China
| | - Yuanyuan Liu
- Department of Endocrinology, The Affiliated Huaian No.1 People’s Hospital of Nanjing Medical University, Huaian, Jiangsu Province, China
| | - Jingjing Ma
- Department of Endocrinology, The Affiliated Huaian No.1 People’s Hospital of Nanjing Medical University, Huaian, Jiangsu Province, China
| | - Yiming Li
- Department of Endocrinology, The Affiliated Huaian No.1 People’s Hospital of Nanjing Medical University, Huaian, Jiangsu Province, China
| | - Yu He
- Department of Endocrinology, The Affiliated Huaian No.1 People’s Hospital of Nanjing Medical University, Huaian, Jiangsu Province, China
| | - Huimin Zhu
- Department of Electrophysiology, The Affiliated Huaian No.1 People’s Hospital of Nanjing Medical University, Huaian, Jiangsu Province, China
| | - Li Mao
- Department of Endocrinology, The Affiliated Huaian No.1 People’s Hospital of Nanjing Medical University, Huaian, Jiangsu Province, China
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Qadri AH, Prajapati J, Faheem I, Bhattacharjee U, Padmanaban HK, Mulukala SKN, Pasupulati AK. Biophysical characterization and insights into the oligomeric nature of CD2-associated protein. INTERNATIONAL JOURNAL OF BIOCHEMISTRY AND MOLECULAR BIOLOGY 2024; 15:20-33. [PMID: 38765876 PMCID: PMC11101965 DOI: 10.62347/uvsh8436] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/05/2023] [Accepted: 02/27/2024] [Indexed: 05/22/2024]
Abstract
INTRODUCTION Glomerular podocytes are specialized epithelial cells localized to the blood-urine interface of the kidney. Podocyte slit-diaphragm (SD), a size-and-charge-selective junction, is instrumental in blood ultrafiltration and the formation of protein-free urine. The SD consists of macromolecular complexes of several proteins, such as nephrin, podocin, and CD2-associated protein (CD2AP). CD2AP is an adapter protein and is considered to be crucial for the integrity of SD. Mutations in the SD proteins cause nephrotic syndrome (NS), characterized by proteinuria. SD proteins' structural features must be elucidated to understand the mechanism of proteinuria in NS. In this study, we expressed, purified, and biophysically characterized heterologously expressed human CD2AP. METHODS Codon-optimized human CD2AP was expressed in E. coli Rosetta cells. The recombinant protein was induced with 1 mM IPTG and purified by Ni-NTA affinity chromatography. Analytical size-exclusion chromatography, blue native-PAGE, circular dichroism, and fluorescence spectroscopy were performed to decipher the oligomeric nature, secondary structural content, and tertiary packing of CD2AP. RESULTS Our analysis revealed that CD2AP adopts a predominantly disordered secondary structure despite exhibiting moderate tertiary packing, characterized by low helical and β-sheet content. CD2AP readily assembles into homo-oligomers, with octamers and tetramers constituting the primary population. Interestingly, the inherent flexibility of CD2AP's secondary structural elements appears resistant to thermal denaturation. Frameshift mutation (p.K579Efs*7) that leads to loss of the coiled-coil domain promotes aberrant oligomerization of CD2AP through SH3 domains. CONCLUSION We successfully expressed full-length human CD2AP in a heterologous system, wherein the secondary structure of CD2AP is predominantly disordered. CD2AP can form higher-order oligomers, and the significance of these oligomers and the impact of mutations in the context of size-selective permeability of SD needs further investigation.
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Affiliation(s)
- Abrar H Qadri
- Department of Biochemistry, University of HyderabadHyderabad 500046, India
| | - Jyotsana Prajapati
- Department of Biochemistry, University of HyderabadHyderabad 500046, India
| | - Iqball Faheem
- Department of Microbiology and Cell Biology, Indian Institute of ScienceBangalore 560012, India
| | - Utsa Bhattacharjee
- Department of Biochemistry, University of HyderabadHyderabad 500046, India
| | | | | | - Anil K Pasupulati
- Department of Biochemistry, University of HyderabadHyderabad 500046, India
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Su Y, Long Y, Xie K. Cingulin family: Structure, function and clinical significance. Life Sci 2024; 341:122504. [PMID: 38354973 DOI: 10.1016/j.lfs.2024.122504] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2023] [Revised: 01/21/2024] [Accepted: 02/11/2024] [Indexed: 02/16/2024]
Abstract
Cingulin and its paralog paracingulin are vital components of the apical junctional complex in vertebrate epithelial and endothelial cells. They are both found in tight junctions (TJ), and paracingulin is also detectable in adherens junctions (AJ) as TJ cytoplasmic plaque proteins. Cingulin and paracingulin interact with other proteins to perform functions. They interact with cytoskeletal proteins, modulate the activity of small GTPases, such as RhoA and Rac1, and regulate gene expression. In addition, cingulin and paracingulin regulate barrier function and many pathological processes, including inflammation and tumorigenesis. In this review, we summarize the discovery and structure, expression and subcellular distribution, and molecular interactions of cingulin family proteins and discuss their role in development, physiology, and pathological processes.
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Affiliation(s)
- Yuling Su
- Center for Pancreatic Cancer Research, The South China University of Technology School of Medicine, Guangzhou, Guangdong 510006, China
| | - You Long
- Center for Pancreatic Cancer Research, The South China University of Technology School of Medicine, Guangzhou, Guangdong 510006, China
| | - Keping Xie
- Center for Pancreatic Cancer Research, The South China University of Technology School of Medicine, Guangzhou, Guangdong 510006, China; The Second Affiliated Hospital and Guangzhou First People's Hospital, South China University of Technology School of Medicine, Guangdong 510006, China; The South China University of Technology Comprehensive Cancer Center, Guangzhou, Guangdong 510006, China.
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Gujarati NA, Chow AK, Mallipattu SK. Central role of podocytes in mediating cellular cross talk in glomerular health and disease. Am J Physiol Renal Physiol 2024; 326:F313-F325. [PMID: 38205544 PMCID: PMC11207540 DOI: 10.1152/ajprenal.00328.2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2023] [Revised: 12/20/2023] [Accepted: 12/20/2023] [Indexed: 01/12/2024] Open
Abstract
Podocytes are highly specialized epithelial cells that surround the capillaries of the glomeruli in the kidney. Together with the glomerular endothelial cells, these postmitotic cells are responsible for regulating filtrate from the circulating blood with their organized network of interdigitating foot processes that wrap around the glomerular basement membrane. Although podocyte injury and subsequent loss is the hallmark of many glomerular diseases, recent evidence suggests that the cell-cell communication between podocytes and other glomerular and nonglomerular cells is critical for the development and progression of kidney disease. In this review, we highlight these key cellular pathways of communication and how they might be a potential target for therapy in glomerular disease. We also postulate that podocytes might serve as a central hub for communication in the kidney under basal conditions and in response to cellular stress, which may have implications for the development and progression of glomerular diseases.
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Affiliation(s)
- Nehaben A Gujarati
- Division of Nephrology, Department of Medicine, Stony Brook University, Stony Brook, New York, United States
| | - Andrew K Chow
- Division of Nephrology, Department of Medicine, Stony Brook University, Stony Brook, New York, United States
| | - Sandeep K Mallipattu
- Division of Nephrology, Department of Medicine, Stony Brook University, Stony Brook, New York, United States
- Renal Section, Northport Veterans Affairs Medical Center, Northport, New York, United States
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Tanzi A, Buono L, Grange C, Iampietro C, Brossa A, Arcolino FO, Arigoni M, Calogero R, Perin L, Deaglio S, Levtchenko E, Peruzzi L, Bussolati B. Urine-derived podocytes from steroid resistant nephrotic syndrome patients as a model for renal-progenitor derived extracellular vesicles effect and drug screening. RESEARCH SQUARE 2024:rs.3.rs-3959549. [PMID: 38464119 PMCID: PMC10925474 DOI: 10.21203/rs.3.rs-3959549/v1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/12/2024]
Abstract
Background Personalized disease models are crucial for assessing the specific response of diseased cells to drugs, particularly novel biological therapeutics. Extracellular vesicles (EVs), nanosized vesicles released by cells for intercellular communication, have gained therapeutic interest due to their ability to reprogram target cells. We here utilized urinary podocytes obtained from children affected by steroid-resistant nephrotic syndrome with characterized genetic mutations as a model to test the therapeutic potential of EVs derived from kidney progenitor cells. Methods EVs were isolated from kidney progenitor cells (nKPCs) derived from the urine of a preterm neonate. Three lines of urinary podocytes obtained from nephrotic patients' urine and a line of Alport patient podocytes were characterized and used to assess albumin permeability in response to various drugs or to nKPC-EVs. RNA sequencing was conducted to identify commonly modulated pathways. Results Podocytes appeared unresponsive to pharmacological treatments, except for a podocyte line demonstrating responsiveness, in alignment with the patient's clinical response at 48 months. At variance, treatment with the nKPC-EVs was able to significantly reduce permeability in all the steroid-resistant patients-derived podocytes as well as in the line of Alport-derived podocytes. RNA sequencing of nKPC-EV-treated podocytes revealed the common upregulation of two genes (small ubiquitin-related modifier 1 (SUMO1) and Sentrin-specific protease 2 (SENP2)) involved in the SUMOylation pathway, a process recently demonstrated to play a role in slit diaphragm stabilization. Gene ontology analysis on podocyte expression profile highlighted cell-to-cell adhesion as the primary upregulated biological activity in treated podocytes. Conclusions nKPCs emerge as a promising non-invasive source of EVs with potential therapeutic effects on podocyte dysfunction. Furthermore, our findings suggest the possibility of establishing a non-invasive in vitro model for screening regenerative compounds on patient-derived podocytes.
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Affiliation(s)
- Adele Tanzi
- University of Turin: Universita degli Studi di Torino
| | - Lola Buono
- University of Turin: Universita degli Studi di Torino
| | | | | | | | | | | | | | | | | | | | - Licia Peruzzi
- Azienda Ospedaliero Universitaria Città della Salute e della Scienza di Torino: Azienda Ospedaliero Universitaria Citta della Salute e della Scienza di Torino
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Tsang TH, Wiese M, Helmstädter M, Stehle T, Seyfferth J, Shvedunova M, Holz H, Walz G, Akhtar A. Transcriptional regulation by the NSL complex enables diversification of IFT functions in ciliated versus nonciliated cells. SCIENCE ADVANCES 2023; 9:eadh5598. [PMID: 37624894 PMCID: PMC10456878 DOI: 10.1126/sciadv.adh5598] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/12/2023] [Accepted: 07/25/2023] [Indexed: 08/27/2023]
Abstract
Members of the NSL histone acetyltransferase complex are involved in multiorgan developmental syndromes. While the NSL complex is known for its importance in early development, its role in fully differentiated cells remains enigmatic. Using a kidney-specific model, we discovered that deletion of NSL complex members KANSL2 or KANSL3 in postmitotic podocytes led to catastrophic kidney dysfunction. Systematic comparison of two primary differentiated cell types reveals the NSL complex as a master regulator of intraciliary transport genes in both dividing and nondividing cells. NSL complex ablation led to loss of cilia and impaired sonic hedgehog pathway in ciliated fibroblasts. By contrast, nonciliated podocytes responded with altered microtubule dynamics and obliterated podocyte functions. Finally, overexpression of wild-type but not a double zinc finger (ZF-ZF) domain mutant of KANSL2 rescued the transcriptional defects, revealing a critical function of this domain in NSL complex assembly and function. Thus, the NSL complex exhibits bifurcation of functions to enable diversity of specialized outcomes in differentiated cells.
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Affiliation(s)
- Tsz Hong Tsang
- Max Planck Institute of Immunobiology and Epigenetics, 79108 Freiburg, Germany
- Faculty of Biology, University of Freiburg, 79104 Freiburg, Germany
- International Max Planck Research School for Molecular and Cellular Biology (IMPRS-MCB), 79108 Freiburg, Germany
| | - Meike Wiese
- Max Planck Institute of Immunobiology and Epigenetics, 79108 Freiburg, Germany
| | - Martin Helmstädter
- Department of Medicine IV, University Freiburg Medical Center, Faculty of Medicine, University of Freiburg, Hugstetter Strasse 55, 79106 Freiburg, Germany
| | - Thomas Stehle
- Max Planck Institute of Immunobiology and Epigenetics, 79108 Freiburg, Germany
| | - Janine Seyfferth
- Max Planck Institute of Immunobiology and Epigenetics, 79108 Freiburg, Germany
| | - Maria Shvedunova
- Max Planck Institute of Immunobiology and Epigenetics, 79108 Freiburg, Germany
| | - Herbert Holz
- Max Planck Institute of Immunobiology and Epigenetics, 79108 Freiburg, Germany
| | - Gerd Walz
- Department of Medicine IV, University Freiburg Medical Center, Faculty of Medicine, University of Freiburg, Hugstetter Strasse 55, 79106 Freiburg, Germany
- BIOSS Centre for Biological Signalling Studies, University of Freiburg, Schänzlestrasse 18, 79104 Freiburg, Germany
- CIBSS Centre for Integrative Biological Signalling Studies, University of Freiburg, Schänzlestrasse 18, 79104 Freiburg, Germany
| | - Asifa Akhtar
- Max Planck Institute of Immunobiology and Epigenetics, 79108 Freiburg, Germany
- CIBSS Centre for Integrative Biological Signalling Studies, University of Freiburg, Schänzlestrasse 18, 79104 Freiburg, Germany
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Robles-Osorio ML, Sabath E. Tight junction disruption and the pathogenesis of the chronic complications of diabetes mellitus: A narrative review. World J Diabetes 2023; 14:1013-1026. [PMID: 37547580 PMCID: PMC10401447 DOI: 10.4239/wjd.v14.i7.1013] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/28/2023] [Revised: 03/20/2023] [Accepted: 05/23/2023] [Indexed: 07/12/2023] Open
Abstract
The chronic complications of diabetes mellitus constitute a major public health problem. For example, diabetic eye diseases are the most important cause of blindness, and diabetic nephropathy is the most frequent cause of chronic kidney disease worldwide. The cellular and molecular mechanisms of these chronic complications are still poorly understood, preventing the development of effective treatment strategies. Tight junctions (TJs) are epithelial intercellular junctions located at the most apical region of cell-cell contacts, and their main function is to restrict the passage of molecules through the paracellular space. The TJs consist of over 40 proteins, and the most important are occludin, claudins and the zonula occludens. Accumulating evidence suggests that TJ disruption in different organs, such as the brain, nerves, retina and kidneys, plays a fundamental pathophysiological role in the development of chronic complications. Increased permeability of the blood-brain barrier and the blood-retinal barrier has been demonstrated in diabetic neuropathy, brain injury and diabetic retinopathy. The consequences of TJ disruption on kidney function or progression of kidney disease are currently unknown. In the present review, we highlighted the molecular events that lead to barrier dysfunction in diabetes. Further investigation of the mechanisms underlying TJ disruption is expected to provide new insights into therapeutic approaches to ameliorate the chronic complications of diabetes mellitus.
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Affiliation(s)
| | - Ernesto Sabath
- Renal and Metabolism Unit, Hospital General de Querétaro, Queretaro 76180, Mexico
- Department of Nutrition, Universidad Autónoma de Queretaro, Queretaro 76230, Mexico
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Gerlach GF, Imseis ZH, Cooper SL, Santos AN, O’Brien LL. Mapping of the podocin proximity-dependent proteome reveals novel components of the kidney podocyte foot process. Front Cell Dev Biol 2023; 11:1195037. [PMID: 37325559 PMCID: PMC10262054 DOI: 10.3389/fcell.2023.1195037] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2023] [Accepted: 05/03/2023] [Indexed: 06/17/2023] Open
Abstract
Introduction: The unique architecture of glomerular podocytes is integral to kidney filtration. Interdigitating foot processes extend from the podocyte cell body, wrap around fenestrated capillaries, and form specialized junctional complexes termed slit diaphragms to create a molecular sieve. However, the full complement of proteins which maintain foot process integrity, and how this localized proteome changes with disease, remain to be elucidated. Methods: Proximity-dependent biotin identification (BioID) enables the identification of spatially localized proteomes. To this end, we developed a novel in vivo BioID knock-in mouse model. We utilized the slit diaphragm protein podocin (Nphs2) to create a podocin-BioID fusion. Podocin-BioID localizes to the slit diaphragm, and biotin injection leads to podocyte-specific protein biotinylation. We isolated the biotinylated proteins and performed mass spectrometry to identify proximal interactors. Results and Discussion: Gene ontology analysis of 54 proteins specifically enriched in our podocin-BioID sample revealed 'cell junctions,' 'actin binding,' and 'cytoskeleton organization' as top terms. Known foot process components were identified, and we further uncovered two novel proteins: the tricellular junctional protein Ildr2 and the CDC42 and N-WASP interactor Fnbp1l. We confirmed that Ildr2 and Fnbp1l are expressed by podocytes and partially colocalize with podocin. Finally, we investigated how this proteome changes with age and uncovered a significant increase in Ildr2. This was confirmed by immunofluorescence on human kidney samples and suggests altered junctional composition may preserve podocyte integrity. Together, these assays have led to new insights into podocyte biology and support the efficacy of utilizing BioID in vivo to interrogate spatially localized proteomes in health, aging, and disease.
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Affiliation(s)
| | | | | | | | - Lori L. O’Brien
- Department of Cell Biology and Physiology, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States
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Lee MS, Devi S, He JC, Zhou W. A zebrafish model of congenital nephrotic syndrome of the Finnish type. Front Cell Dev Biol 2022; 10:976043. [PMID: 36187478 PMCID: PMC9515793 DOI: 10.3389/fcell.2022.976043] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2022] [Accepted: 08/12/2022] [Indexed: 11/13/2022] Open
Abstract
Nephrotic syndrome (NS) is a disease characterized by proteinuria and subsequent hypoalbuminemia, hyperlipidemia and edema due to the defective renal glomerular filtration barrier (GFB). Mutations of NPHS1, encoding NEPHRIN, a podocyte protein essential for normal GFB, cause congenital nephrotic syndrome (CNS) of the Finnish type (CNF), which accounts for about 50% of CNS cases. We generated zebrafish nphs1 mutants by using CRISPR/Cas9. These mutants completely lack nephrin proteins in podocytes and develop progressive peri-orbital and whole-body edema after 5 days post fertilization. Ultra-structurally, loss of nephrin results in absence of slit-diaphragms and progressive foot process effacement in zebrafish pronephric glomeruli, similar to the pathological changes in human CNF patients. Interestingly, some nphs1 mutants are viable to adulthood despite ultra-structural defects in renal glomeruli. Using a reporter line Tg (l-fabp:VDBP-GFP) expressing GFP-tagged vitamin-D-binding protein in the blood plasma, we observed a reduction of intravascular GFP fluorescence in the nphs1 mutants, a hypoalbuminemia-like phenotype. In addition, we detected excretion of GFP by the nphs1 mutants, reminiscent of proteinuria. Therefore, we have demonstrated that the nphs1 mutant zebrafish recapitulate the human NS phenotypes and provide a novel and relevant animal model useful for screening therapeutical agents for this disease.
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Affiliation(s)
- Mi-Sun Lee
- Michigan Neuroscience Institute, University of Michigan, Ann Arbor, MI, United States
| | - Sulochana Devi
- Michigan Neuroscience Institute, University of Michigan, Ann Arbor, MI, United States
| | - John Cijiang He
- Division of Nephrology, Department of Medicine, Icahn School of Medicine at Mount Sinai, New York, NY, United States
- *Correspondence: John Cijiang He, ; Weibin Zhou,
| | - Weibin Zhou
- Division of Nephrology, Department of Medicine, Icahn School of Medicine at Mount Sinai, New York, NY, United States
- *Correspondence: John Cijiang He, ; Weibin Zhou,
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12
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Hansen J, Sealfon R, Menon R, Eadon MT, Lake BB, Steck B, Anjani K, Parikh S, Sigdel TK, Zhang G, Velickovic D, Barwinska D, Alexandrov T, Dobi D, Rashmi P, Otto EA, Rivera M, Rose MP, Anderton CR, Shapiro JP, Pamreddy A, Winfree S, Xiong Y, He Y, de Boer IH, Hodgin JB, Barisoni L, Naik AS, Sharma K, Sarwal MM, Zhang K, Himmelfarb J, Rovin B, El-Achkar TM, Laszik Z, He JC, Dagher PC, Valerius MT, Jain S, Satlin LM, Troyanskaya OG, Kretzler M, Iyengar R, Azeloglu EU. A reference tissue atlas for the human kidney. SCIENCE ADVANCES 2022; 8:eabn4965. [PMID: 35675394 PMCID: PMC9176741 DOI: 10.1126/sciadv.abn4965] [Citation(s) in RCA: 68] [Impact Index Per Article: 34.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/03/2021] [Accepted: 04/20/2022] [Indexed: 05/08/2023]
Abstract
Kidney Precision Medicine Project (KPMP) is building a spatially specified human kidney tissue atlas in health and disease with single-cell resolution. Here, we describe the construction of an integrated reference map of cells, pathways, and genes using unaffected regions of nephrectomy tissues and undiseased human biopsies from 56 adult subjects. We use single-cell/nucleus transcriptomics, subsegmental laser microdissection transcriptomics and proteomics, near-single-cell proteomics, 3D and CODEX imaging, and spatial metabolomics to hierarchically identify genes, pathways, and cells. Integrated data from these different technologies coherently identify cell types/subtypes within different nephron segments and the interstitium. These profiles describe cell-level functional organization of the kidney following its physiological functions and link cell subtypes to genes, proteins, metabolites, and pathways. They further show that messenger RNA levels along the nephron are congruent with the subsegmental physiological activity. This reference atlas provides a framework for the classification of kidney disease when multiple molecular mechanisms underlie convergent clinical phenotypes.
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Affiliation(s)
- Jens Hansen
- Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Rachel Sealfon
- Princeton University, Princeton, NJ, USA
- Flatiron Institute, New York, NY, USA
| | - Rajasree Menon
- University of Michigan School of Medicine, Ann Arbor, MI, USA
| | | | - Blue B. Lake
- Department of Bioengineering, University of California San Diego, La Jolla, CA, USA
| | - Becky Steck
- University of Michigan School of Medicine, Ann Arbor, MI, USA
| | - Kavya Anjani
- University of California San Francisco School of Medicine, San Francisco, CA, USA
| | - Samir Parikh
- Ohio State University College of Medicine, Columbus, OH, USA
| | - Tara K. Sigdel
- University of California San Francisco School of Medicine, San Francisco, CA, USA
| | - Guanshi Zhang
- University of Texas–Health San Antonio School of Medicine, San Antonio, TX, USA
| | | | - Daria Barwinska
- Indiana University School of Medicine, Indianapolis, IN, USA
| | | | - Dejan Dobi
- University of California San Francisco School of Medicine, San Francisco, CA, USA
| | - Priyanka Rashmi
- University of California San Francisco School of Medicine, San Francisco, CA, USA
| | - Edgar A. Otto
- University of Michigan School of Medicine, Ann Arbor, MI, USA
| | - Miguel Rivera
- University of California San Francisco School of Medicine, San Francisco, CA, USA
| | - Michael P. Rose
- University of Michigan School of Medicine, Ann Arbor, MI, USA
| | - Christopher R. Anderton
- University of Texas–Health San Antonio School of Medicine, San Antonio, TX, USA
- Pacific Northwest National Laboratory, Richland, WA, USA
| | - John P. Shapiro
- Ohio State University College of Medicine, Columbus, OH, USA
| | - Annapurna Pamreddy
- University of Texas–Health San Antonio School of Medicine, San Antonio, TX, USA
| | - Seth Winfree
- Indiana University School of Medicine, Indianapolis, IN, USA
| | - Yuguang Xiong
- Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Yongqun He
- University of Michigan School of Medicine, Ann Arbor, MI, USA
| | - Ian H. de Boer
- Schools of Medicine and Public Health, University of Washington, Seattle, WA, USA
| | | | | | - Abhijit S. Naik
- University of Michigan School of Medicine, Ann Arbor, MI, USA
| | - Kumar Sharma
- University of Texas–Health San Antonio School of Medicine, San Antonio, TX, USA
| | - Minnie M. Sarwal
- University of California San Francisco School of Medicine, San Francisco, CA, USA
| | - Kun Zhang
- Department of Bioengineering, University of California San Diego, La Jolla, CA, USA
| | - Jonathan Himmelfarb
- Schools of Medicine and Public Health, University of Washington, Seattle, WA, USA
| | - Brad Rovin
- Ohio State University College of Medicine, Columbus, OH, USA
| | | | - Zoltan Laszik
- University of California San Francisco School of Medicine, San Francisco, CA, USA
| | | | | | - M. Todd Valerius
- Brigham and Women’s Hospital, Harvard Medical School, Cambridge, MA, USA
| | - Sanjay Jain
- Washington University in Saint Louis School of Medicine, St. Louis, MS, USA
| | - Lisa M. Satlin
- Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Olga G. Troyanskaya
- Princeton University, Princeton, NJ, USA
- Flatiron Institute, New York, NY, USA
| | | | - Ravi Iyengar
- Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | | | - Kidney Precision Medicine Project
- Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Princeton University, Princeton, NJ, USA
- Flatiron Institute, New York, NY, USA
- University of Michigan School of Medicine, Ann Arbor, MI, USA
- Indiana University School of Medicine, Indianapolis, IN, USA
- Department of Bioengineering, University of California San Diego, La Jolla, CA, USA
- University of California San Francisco School of Medicine, San Francisco, CA, USA
- Ohio State University College of Medicine, Columbus, OH, USA
- University of Texas–Health San Antonio School of Medicine, San Antonio, TX, USA
- Pacific Northwest National Laboratory, Richland, WA, USA
- European Molecular Biology Laboratory, Heidelberg, Germany
- Schools of Medicine and Public Health, University of Washington, Seattle, WA, USA
- Duke University School of Medicine, Durham, NC, USA
- Brigham and Women’s Hospital, Harvard Medical School, Cambridge, MA, USA
- Washington University in Saint Louis School of Medicine, St. Louis, MS, USA
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13
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Fishel Bartal M, Lindheimer MD, Sibai BM. Proteinuria during pregnancy: definition, pathophysiology, methodology, and clinical significance. Am J Obstet Gynecol 2022; 226:S819-S834. [PMID: 32882208 DOI: 10.1016/j.ajog.2020.08.108] [Citation(s) in RCA: 38] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2020] [Revised: 08/24/2020] [Accepted: 08/27/2020] [Indexed: 12/31/2022]
Abstract
Qualitative and quantitative measurement of urine protein excretion is one of the most common tests performed during pregnancy. For more than 100 years, proteinuria was necessary for the diagnosis of preeclampsia, but recent guidelines recommend that proteinuria is sufficient but not necessary for the diagnosis. Still, in clinical practice, most patients with gestational hypertension will be diagnosed as having preeclampsia based on the presence of proteinuria. Although the reference standard for measuring urinary protein excretion is a 24-hour urine collection, spot urine protein-to-creatinine ratio is a reasonable "rule-out" test for proteinuria. Urine dipstick screening for proteinuria does not provide any clinical benefit and should not be used to diagnose proteinuria. The classic cutoff cited to define proteinuria during pregnancy is a value of >300 mg/24 hours or a urine protein-to-creatinine ratio of at least 0.3. Using this cutoff, the rate of isolated proteinuria in pregnancy may reach 8%, whereas preeclampsia occurs among 3% to 8% of pregnancies. Although this threshold is widely accepted, its origin is not based on evidence on adverse pregnancy outcomes but rather on expert opinion and results of small studies. After reviewing the available data, the most important factor that influences maternal and neonatal outcome is the severity of blood pressures and presence of end organ damage, rather than the excess protein excretion. Because the management of gestational hypertension and preeclampsia without severe features is almost identical in frequency of surveillance and timing of delivery, the separation into 2 disorders is unnecessary. If the management of women with gestational hypertension with a positive assessment of proteinuria will not change, we believe that urine assessment for proteinuria is unnecessary in women who develop new-onset blood pressure at or after 20 weeks' gestation. Furthermore, we do not recommend repeated measurement of proteinuria for women with preeclampsia, the amount of proteinuria does not seem to be related to poor maternal and neonatal outcomes, and monitoring proteinuria may lead to unindicated preterm deliveries and related neonatal complications. Our current diagnosis of preeclampsia in women with chronic kidney disease may be based on a change in protein excretion, a baseline protein excretion evaluation is critical in certain conditions such as chronic hypertension, diabetes, and autoimmune or other renal disorders. The current definition of superimposed preeclampsia possesses a diagnostic dilemma, and it is unclear whether a change in the baseline proteinuria reflects another systemic disease such as preeclampsia or whether women with chronic disease such as chronic hypertension or diabetes will experience a different "normal" pattern of protein excretion during pregnancy. Finally, limited data are available regarding angiogenic and other biomarkers in women with chronic kidney disease as a potential aid in distinguishing the worsening of baseline chronic kidney disease and chronic hypertension from superimposed preeclampsia.
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Abstract
Rho family GTPases are molecular switches best known for their pivotal role in dynamic regulation of the actin cytoskeleton, but also of cellular morphology, motility, adhesion and proliferation. The prototypic members of this family (RhoA, Rac1 and Cdc42) also contribute to the normal kidney function and play important roles in the structure and function of various kidney cells including tubular epithelial cells, mesangial cells and podocytes. The kidney's vital filtration function depends on the structural integrity of the glomerulus, the proximal portion of the nephron. Within the glomerulus, the architecturally actin-based cytoskeleton podocyte forms the final cellular barrier to filtration. The glomerulus appears as a highly dynamic signalling hub that is capable of integrating intracellular cues from its individual structural components. Dynamic regulation of the podocyte cytoskeleton is required for efficient barrier function of the kidney. As master regulators of actin cytoskeletal dynamics, Rho GTPases are therefore of critical importance for sustained kidney barrier function. Dysregulated activities of the Rho GTPases and of their effectors are implicated in the pathogenesis of both hereditary and idiopathic forms of kidney diseases. Diabetic nephropathy is a progressive kidney disease that is caused by injury to kidney glomeruli. High glucose activates RhoA/Rho-kinase in mesangial cells, leading to excessive extracellular matrix production (glomerulosclerosis). This RhoA/Rho-kinase pathway also seems involved in the post-transplant hypertension frequently observed during treatment with calcineurin inhibitors, whereas Rac1 activation was observed in post-transplant ischaemic acute kidney injury.
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Affiliation(s)
- Clara Steichen
- Inserm UMR-1082 Irtomit, Poitiers, France,Faculté De Médecine Et De Pharmacie, Université De Poitiers, Poitiers, France
| | - Claude Hervé
- Inserm UMR-1082 Irtomit, Poitiers, France,CONTACT Claude HervéInserm UMR-1082 Irtomit, Poitiers, France
| | - Thierry Hauet
- Inserm UMR-1082 Irtomit, Poitiers, France,Faculté De Médecine Et De Pharmacie, Université De Poitiers, Poitiers, France,Department of Medical Biology, Service De Biochimie, CHU De Poitiers, Poitiers, France
| | - Nicolas Bourmeyster
- Faculté De Médecine Et De Pharmacie, Université De Poitiers, Poitiers, France,Department of Medical Biology, Service De Biochimie, CHU De Poitiers, Poitiers, France,Laboratoire STIM CNRS ERL 7003, Université de Poitiers, Poitiers Cédex, France
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15
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Agarwal S, Sudhini YR, Polat OK, Reiser J, Altintas MM. Renal cell markers: lighthouses for managing renal diseases. Am J Physiol Renal Physiol 2021; 321:F715-F739. [PMID: 34632812 DOI: 10.1152/ajprenal.00182.2021] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Kidneys, one of the vital organs in our body, are responsible for maintaining whole body homeostasis. The complexity of renal function (e.g., filtration, reabsorption, fluid and electrolyte regulation, and urine production) demands diversity not only at the level of cell types but also in their overall distribution and structural framework within the kidney. To gain an in depth molecular-level understanding of the renal system, it is imperative to discern the components of kidney and the types of cells residing in each of the subregions. Recent developments in labeling, tracing, and imaging techniques have enabled us to mark, monitor, and identify these cells in vivo with high efficiency in a minimally invasive manner. In this review, we summarize different cell types, specific markers that are uniquely associated with those cell types, and their distribution in the kidney, which altogether make kidneys so special and different. Cellular sorting based on the presence of certain proteins on the cell surface allowed for the assignment of multiple markers for each cell type. However, different studies using different techniques have found contradictions in cell type-specific markers. Thus, the term "cell marker" might be imprecise and suboptimal, leading to uncertainty when interpreting the data. Therefore, we strongly believe that there is an unmet need to define the best cell markers for a cell type. Although the compendium of renal-selective marker proteins presented in this review is a resource that may be useful to researchers, we acknowledge that the list may not be necessarily exhaustive.
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Affiliation(s)
- Shivangi Agarwal
- Department of Internal Medicine, Rush University, Chicago, Illinois
| | | | - Onur K Polat
- Department of Internal Medicine, Rush University, Chicago, Illinois
| | - Jochen Reiser
- Department of Internal Medicine, Rush University, Chicago, Illinois
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16
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Wang B, Qian JY, Tang TT, Lin LL, Yu N, Guo HL, Ni WJ, Lv LL, Wen Y, Li ZL, Wu M, Cao JY, Liu BC. VDR/Atg3 Axis Regulates Slit Diaphragm to Tight Junction Transition via p62-Mediated Autophagy Pathway in Diabetic Nephropathy. Diabetes 2021; 70:2639-2651. [PMID: 34376476 DOI: 10.2337/db21-0205] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/09/2021] [Accepted: 08/01/2021] [Indexed: 12/09/2022]
Abstract
Foot process effacement is an important feature of early diabetic nephropathy (DN), which is closely related to the development of albuminuria. Under certain nephrotic conditions, the integrity and function of the glomerular slit diaphragm (SD) structure were impaired and replaced by the tight junction (TJ) structure, resulting in so-called SD-TJ transition, which could partially explain the effacement of foot processes at the molecular level. However, the mechanism underlying the SD-TJ transition has not been described in DN. Here, we demonstrated that impaired autophagic flux blocked p62-mediated degradation of ZO-1 (TJ protein) and promoted podocytes injury via activation of caspase3 and caspase8. Interestingly, the expression of VDR in podocytes was decreased under diabetes conditions, which impaired autophagic flux through downregulating Atg3. Of note, we also found that VDR abundance was negatively associated with impaired autophagic flux and SD-TJ transition in the glomeruli from human renal biopsy samples with DN. Furthermore, VDR activation improved autophagic flux and attenuated SD-TJ transition in the glomeruli of diabetic animal models. In conclusion, our data provided the novel insight that VDR/Atg3 axis deficiency resulted in SD-TJ transition and foot processes effacement via blocking the p62-mediated autophagy pathway in DN.
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Affiliation(s)
- Bin Wang
- Institute of Nephrology, Zhong Da Hospital, Southeast University School of Medicine, Nanjing, China
| | - Jing-Yi Qian
- Institute of Nephrology, Zhong Da Hospital, Southeast University School of Medicine, Nanjing, China
| | - Tao-Tao Tang
- Institute of Nephrology, Zhong Da Hospital, Southeast University School of Medicine, Nanjing, China
| | - Li-Lu Lin
- Division of Nephrology, The Fifth People's Hospital of Shanghai, Fudan University, Shanghai, China
| | - Nan Yu
- Division of Nephrology, The Fifth People's Hospital of Shanghai, Fudan University, Shanghai, China
| | - Hong-Lei Guo
- Department of Nephrology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China
| | - Wei-Jie Ni
- Institute of Nephrology, Zhong Da Hospital, Southeast University School of Medicine, Nanjing, China
| | - Ling-Li Lv
- Institute of Nephrology, Zhong Da Hospital, Southeast University School of Medicine, Nanjing, China
| | - Yi Wen
- Institute of Nephrology, Zhong Da Hospital, Southeast University School of Medicine, Nanjing, China
| | - Zuo-Lin Li
- Institute of Nephrology, Zhong Da Hospital, Southeast University School of Medicine, Nanjing, China
| | - Min Wu
- Institute of Nephrology, Zhong Da Hospital, Southeast University School of Medicine, Nanjing, China
| | - Jing-Yuan Cao
- Institute of Nephrology, Zhong Da Hospital, Southeast University School of Medicine, Nanjing, China
| | - Bi-Cheng Liu
- Institute of Nephrology, Zhong Da Hospital, Southeast University School of Medicine, Nanjing, China
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17
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Shankland SJ, Wang Y, Shaw AS, Vaughan JC, Pippin JW, Wessely O. Podocyte Aging: Why and How Getting Old Matters. J Am Soc Nephrol 2021; 32:2697-2713. [PMID: 34716239 PMCID: PMC8806106 DOI: 10.1681/asn.2021050614] [Citation(s) in RCA: 31] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2021] [Accepted: 08/26/2021] [Indexed: 02/04/2023] Open
Abstract
The effects of healthy aging on the kidney, and how these effects intersect with superimposed diseases, are highly relevant in the context of the population's increasing longevity. Age-associated changes to podocytes, which are terminally differentiated glomerular epithelial cells, adversely affect kidney health. This review discusses the molecular and cellular mechanisms underlying podocyte aging, how these mechanisms might be augmented by disease in the aged kidney, and approaches to mitigate progressive damage to podocytes. Furthermore, we address how biologic pathways such as those associated with cellular growth confound aging in humans and rodents.
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Affiliation(s)
- Stuart J. Shankland
- Division of Nephrology, University of Washington, Seattle, Washington
- Institute for Stem Cell & Regenerative Medicine, University of Washington, Seattle, Washington
| | - Yuliang Wang
- Institute for Stem Cell & Regenerative Medicine, University of Washington, Seattle, Washington
- Paul G. Allen School of Computer Science and Engineering, University of Washington, Seattle, Washington
| | - Andrey S. Shaw
- Department of Research Biology, Genentech, South San Francisco, California
| | - Joshua C. Vaughan
- Department of Chemistry, University of Washington, Seattle, Washington
- Department of Physiology and Biophysics, University of Washington, Seattle, Washington
| | - Jeffrey W. Pippin
- Division of Nephrology, University of Washington, Seattle, Washington
| | - Oliver Wessely
- Lerner Research Institute, Department of Cardiovascular & Metabolic Sciences, Cleveland Clinic Foundation, Cleveland, Ohio
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18
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Rogacka D. Insulin resistance in glomerular podocytes: Potential mechanisms of induction. Arch Biochem Biophys 2021; 710:109005. [PMID: 34371008 DOI: 10.1016/j.abb.2021.109005] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2021] [Revised: 07/19/2021] [Accepted: 08/05/2021] [Indexed: 01/15/2023]
Abstract
Glomerular podocytes are a target for the actions of insulin. Accumulating evidence indicates that exposure to nutrient overload induces insulin resistance in these cells, manifested by abolition of the stimulatory effect of insulin on glucose uptake. Numerous recent studies have investigated potential mechanisms of the induction of insulin resistance in podocytes. High glucose concentrations stimulated reactive oxygen species production through NADPH oxidase activation, decreased adenosine monophosphate-activated protein kinase (AMPK) phosphorylation, and reduced deacetylase sirtuin 1 (SIRT1) protein levels and activity. Calcium signaling involving transient receptor potential cation channel C, member 6 (TRPC6) also was demonstrated to play an essential role in the regulation of insulin-dependent signaling and glucose uptake in podocytes. Furthermore, podocytes exposed to diabetic environment, with elevated insulin levels become insulin resistant as a result of degradation of insulin receptor (IR), resulting in attenuation of insulin signaling responsiveness. Also elevated levels of palmitic acid appear to be an important factor and contributor to podocytes insulin resistance. This review summarizes cellular and molecular alterations that contribute to the development of insulin resistance in glomerular podocytes.
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Affiliation(s)
- Dorota Rogacka
- Mossakowski Medical Research Institute, Polish Academy of Sciences, Laboratory of Molecular and Cellular Nephrology, Wita Stwosza 63, 80-308, Gdansk, Poland; University of Gdansk, Faculty of Chemistry, Department of Molecular Biotechnology, Wita Stwosza 63, 80-308, Gdansk, Poland.
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19
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Zhang H, Lin L, Liu J, Pan L, Lin Z, Zhang M, Zhang J, Cao Y, Zhu J, Zhang R. Phase Separation of MAGI2-Mediated Complex Underlies Formation of Slit Diaphragm Complex in Glomerular Filtration Barrier. J Am Soc Nephrol 2021; 32:1946-1960. [PMID: 34330769 PMCID: PMC8455267 DOI: 10.1681/asn.2020111590] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2020] [Accepted: 03/22/2021] [Indexed: 02/04/2023] Open
Abstract
BACKGROUND Slit diaphragm is a specialized adhesion junction between the opposing podocytes, establishing the final filtration barrier to urinary protein loss. At the cytoplasmic insertion site of each slit diaphragm there is an electron-dense and protein-rich cellular compartment that is essential for slit diaphragm integrity and signal transduction. Mutations in genes that encode components of this membrane-less compartment have been associated with glomerular diseases. However, the molecular mechanism governing formation of compartmentalized slit diaphragm assembly remains elusive. METHODS We systematically investigated the interactions between key components at slit diaphragm, such as MAGI2, Dendrin, and CD2AP, through a combination of biochemical, biophysical, and cell biologic approaches. RESULTS We demonstrated that MAGI2, a unique MAGUK family scaffold protein at slit diaphragm, can autonomously undergo liquid-liquid phase separation. Multivalent interactions among the MAGI2-Dendrin-CD2AP complex drive the formation of the highly dense slit diaphragm condensates at physiologic conditions. The reconstituted slit diaphragm condensates can effectively recruit Nephrin. A nephrotic syndrome-associated mutation of MAGI2 interfered with formation of the slit diaphragm condensates, thus leading to impaired enrichment of Nephrin. CONCLUSIONS Key components at slit diaphragm (e.g., MAGI2 and its complex) can spontaneously undergo phase separation. The reconstituted slit diaphragm condensates can be enriched in adhesion molecules and cytoskeletal adaptor proteins. Therefore, the electron-dense slit diaphragm assembly might form via phase separation of core components of the slit diaphragm in podocytes.
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Affiliation(s)
- Haijiao Zhang
- State Key Laboratory of Cell Biology, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences Center for Excellence in Molecular Cell Science, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Shanghai, China
| | - Lin Lin
- Bio-X Institutes, Key Laboratory for the Genetics of Developmental and Neuropsychiatric Disorders, Ministry of Education, Shanghai Jiao Tong University, Shanghai, China
| | - Jianping Liu
- State Key Laboratory of Bioorganic and Natural Products Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai, China
| | - Lifeng Pan
- State Key Laboratory of Bioorganic and Natural Products Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai, China
| | - Zhijie Lin
- Division of Life Science, State Key Laboratory of Molecular Neuroscience, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China
| | - Mingjie Zhang
- Division of Life Science, State Key Laboratory of Molecular Neuroscience, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China,School of Life Sciences, Southern University of Science and Technology, Shenzhen, China
| | - Jiong Zhang
- School of Life Sciences and Technology, Tongji University, Shanghai, China
| | - Ying Cao
- School of Life Sciences and Technology, Tongji University, Shanghai, China
| | - Jinwei Zhu
- Bio-X Institutes, Key Laboratory for the Genetics of Developmental and Neuropsychiatric Disorders, Ministry of Education, Shanghai Jiao Tong University, Shanghai, China
| | - Rongguang Zhang
- State Key Laboratory of Cell Biology, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences Center for Excellence in Molecular Cell Science, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Shanghai, China
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20
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Rogacka D, Piwkowska A. Beneficial effects of metformin on glomerular podocytes in diabetes. Biochem Pharmacol 2021; 192:114687. [PMID: 34274355 DOI: 10.1016/j.bcp.2021.114687] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2021] [Revised: 07/12/2021] [Accepted: 07/13/2021] [Indexed: 01/15/2023]
Abstract
Podocytes and their foot processes form an important cellular layer of the glomerular barrier involved in regulating glomerular permeability. Disturbances in podocyte function play a central role in the development of proteinuria in diabetic nephropathy. The retraction of podocyte foot processes forming a slit diaphragm is a common feature of proteinuria. Metformin is an oral antidiabetic agent of the biguanide class that is widely recommended for the treatment of high blood glucose in patients with type 2 diabetes mellitus. In addition to lowering glucose, several recent studies have reported potential beneficial effects of metformin on diabetic kidney function. Furthermore, a key molecule of the antidiabetic mechanism of action of metformin is adenosine 5'-monophospate-activated protein kinase (AMPK), as the metformin-induced activation of AMPK is well documented. The present review summarizes current knowledge on the protective effects of metformin against pathological changes in podocytes that are induced by hyperglycemia.
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Affiliation(s)
- Dorota Rogacka
- Laboratory of Molecular and Cellular Nephrology, Mossakowski Medical Research Institute Polish Academy of Sciences, Wita Stwosza 63, Gdansk 80-308, Poland; Department of Molecular Biotechnology, Faculty of Chemistry, University of Gdansk, Wita Stwosza 63, Gdansk 80-308, Poland
| | - Agnieszka Piwkowska
- Laboratory of Molecular and Cellular Nephrology, Mossakowski Medical Research Institute Polish Academy of Sciences, Wita Stwosza 63, Gdansk 80-308, Poland; Department of Molecular Biotechnology, Faculty of Chemistry, University of Gdansk, Wita Stwosza 63, Gdansk 80-308, Poland.
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21
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Haley KE, Elshani M, Um IH, Bell C, Caie PD, Harrison DJ, Reynolds PA. YAP Translocation Precedes Cytoskeletal Rearrangement in Podocyte Stress Response: A Podometric Investigation of Diabetic Nephropathy. Front Physiol 2021; 12:625762. [PMID: 34335284 PMCID: PMC8320019 DOI: 10.3389/fphys.2021.625762] [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: 11/03/2020] [Accepted: 05/21/2021] [Indexed: 11/13/2022] Open
Abstract
Podocyte loss plays a pivotal role in the pathogenesis of glomerular disease. However, the mechanisms underlying podocyte damage and loss remain poorly understood. Although detachment of viable cells has been documented in experimental Diabetic Nephropathy, correlations between reduced podocyte density and disease severity have not yet been established. YAP, a mechanosensing protein, has recently been shown to correlate with glomerular disease progression, however, the underlying mechanism has yet to be fully elucidated. In this study, we sought to document podocyte density in Diabetic Nephropathy using an amended podometric methodology, and to investigate the interplay between YAP and cytoskeletal integrity during podocyte injury. Podocyte density was quantified using TLE4 and GLEPP1 multiplexed immunofluorescence. Fourteen Diabetic Nephropathy cases were analyzed for both podocyte density and cytoplasmic translocation of YAP via automated image analysis. We demonstrate a significant decrease in podocyte density in Grade III/IV cases (124.5 per 106 μm3) relative to Grade I/II cases (226 per 106 μm3) (Student's t-test, p < 0.001), and further show that YAP translocation precedes cytoskeletal rearrangement following injury. Based on these findings we hypothesize that a significant decrease in podocyte density in late grade Diabetic Nephropathy may be explained by early cytoplasmic translocation of YAP.
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Affiliation(s)
- Kathryn E Haley
- School of Medicine, University of St Andrews, St Andrews, United Kingdom.,Biomedical Sciences Research Complex (BSRC), University of St Andrews, St Andrews, United Kingdom
| | - Mustafa Elshani
- School of Medicine, University of St Andrews, St Andrews, United Kingdom.,Directorate of Laboratory Medicine, Lothian University Hospitals Trust, Royal Infirmary, Edinburgh, United Kingdom
| | - In Hwa Um
- School of Medicine, University of St Andrews, St Andrews, United Kingdom
| | - Cameron Bell
- School of Medicine, University of St Andrews, St Andrews, United Kingdom.,Acute Internal Medicine, Queen Elizabeth University Hospital, Glasgow, United Kingdom
| | - Peter D Caie
- School of Medicine, University of St Andrews, St Andrews, United Kingdom
| | - David J Harrison
- School of Medicine, University of St Andrews, St Andrews, United Kingdom.,Directorate of Laboratory Medicine, Lothian University Hospitals Trust, Royal Infirmary, Edinburgh, United Kingdom
| | - Paul A Reynolds
- School of Medicine, University of St Andrews, St Andrews, United Kingdom.,Biomedical Sciences Research Complex (BSRC), University of St Andrews, St Andrews, United Kingdom
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22
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Tesch F, Siegerist F, Hay E, Artelt N, Daniel C, Amann K, Zimmermann U, Kavvadas P, Grisk O, Chadjichristos C, Endlich K, Chatziantoniou C, Endlich N. Super-resolved local recruitment of CLDN5 to filtration slits implicates a direct relationship with podocyte foot process effacement. J Cell Mol Med 2021; 25:7631-7641. [PMID: 34156149 PMCID: PMC8358871 DOI: 10.1111/jcmm.16519] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2021] [Revised: 03/22/2021] [Accepted: 03/24/2021] [Indexed: 11/28/2022] Open
Abstract
Under healthy conditions, foot processes of neighbouring podocytes are interdigitating and connected by an electron‐dense slit diaphragm. Besides slit diaphragm proteins, typical adherens junction proteins are also found to be expressed at this cell‐cell junction. It is therefore considered as a highly specialized type of adherens junction. During podocyte injury, podocyte foot processes lose their characteristic 3D structure and the filtration slits typical meandering structure gets linearized. It is still under debate how this change of structure leads to the phenomenon of proteinuria. Using super‐resolution 3D‐structured illumination microscopy, we observed a spatially restricted up‐regulation of the tight junction protein claudin‐5 (CLDN5) in areas where podocyte processes of patients suffering from minimal change disease (MCD), focal and segmental glomerulosclerosis (FSGS) as well as in murine nephrotoxic serum (NTS) nephritis and uninephrectomy DOCA‐salt hypertension models, were locally injured. CLDN5/nephrin ratios in human glomerulopathies and NTS‐treated mice were significantly higher compared to controls. In patients, the CLDN5/nephrin ratio is significantly correlated with the filtration slit density as a foot process effacement marker, confirming a direct association of local CLDN5 up‐regulation in injured foot processes. Moreover, CLDN5 up‐regulation was observed in some areas of high filtration slit density, suggesting that CLND5 up‐regulation preceded the changes of foot processes. Therefore, CLDN5 could serve as a biomarker predicting early foot process effacement.
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Affiliation(s)
- Florian Tesch
- Department of Anatomy and Cell Biology, University Medicine Greifswald, Greifswald, Germany
| | - Florian Siegerist
- Department of Anatomy and Cell Biology, University Medicine Greifswald, Greifswald, Germany
| | - Eleonora Hay
- Department of Anatomy and Cell Biology, University Medicine Greifswald, Greifswald, Germany.,Department of Mental and Physical Health and Preventive Medicine, Section of Human Anatomy, University of Campania "Luigi Vanvitelli", Naples, Italy
| | - Nadine Artelt
- Department of Anatomy and Cell Biology, University Medicine Greifswald, Greifswald, Germany
| | - Christoph Daniel
- Department of Nephropathology, Institute of Pathology, University of Erlangen-Nuremberg, Erlangen, Germany
| | - Kerstin Amann
- Department of Nephropathology, Institute of Pathology, University of Erlangen-Nuremberg, Erlangen, Germany
| | - Uwe Zimmermann
- Department of Urology, University Medicine Greifswald, Greifswald, Germany
| | | | - Olaf Grisk
- Institute for Physiology, Medizinische Hochschule Brandenburg Theodor Fontane, Neuruppin, Germany
| | | | - Karlhans Endlich
- Department of Anatomy and Cell Biology, University Medicine Greifswald, Greifswald, Germany
| | | | - Nicole Endlich
- Department of Anatomy and Cell Biology, University Medicine Greifswald, Greifswald, Germany
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23
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Mysh M, Poulton JS. The Basolateral Polarity Module Promotes Slit Diaphragm Formation in Drosophila Nephrocytes, a Model of Vertebrate Podocytes. J Am Soc Nephrol 2021; 32:1409-1424. [PMID: 33795424 PMCID: PMC8259641 DOI: 10.1681/asn.2020071050] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2020] [Accepted: 02/12/2021] [Indexed: 02/04/2023] Open
Abstract
BACKGROUND Podocyte slit diaphragms (SDs) are intercellular junctions that function as size-selective filters, excluding most proteins from urine. Abnormalities in SDs cause proteinuria and nephrotic syndrome. Podocytes exhibit apicobasal polarity, which can affect fundamental aspects of cell biology, including morphology, intercellular junction formation, and asymmetric protein distribution along the plasma membrane. Apical polarity protein mutations cause nephrotic syndrome, and data suggest apical polarity proteins regulate SD formation. However, there is no evidence that basolateral polarity proteins regulate SDs. Thus, the role of apicobasal polarity in podocytes remains unclear. METHODS Genetic manipulations and transgenic reporters determined the effects of disrupting apicobasal polarity proteins in Drosophila nephrocytes, which have SDs similar to those of mammalian podocytes. Confocal and electron microscopy were used to characterize SD integrity after loss of basolateral polarity proteins, and genetic-interaction studies illuminated relationships among apicobasal polarity proteins. RESULTS The study identified four novel regulators of nephrocyte SDs: Dlg, Lgl, Scrib, and Par-1. These proteins comprise the basolateral polarity module and its effector kinase. The data suggest these proteins work together, with apical polarity proteins, to regulate SDs by promoting normal endocytosis and trafficking of SD proteins. CONCLUSIONS Given the recognized importance of apical polarity proteins and SD protein trafficking in podocytopathies, the findings connecting basolateral polarity proteins to these processes significantly advance our understanding of SD regulation.
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Affiliation(s)
- Michael Mysh
- Department of Biology, UNC Kidney Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina
| | - John S. Poulton
- Division of Nephrology and Hypertension, Department of Medicine, UNC Kidney Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina
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24
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Cobb MB, Wu W, Attipoe EM, Johnson AC, Garrett MR. Nephron-deficient HSRA rats exhibit renal injury with age but have limited renal damage from streptozotocin-induced hyperglycemia. Am J Physiol Renal Physiol 2021; 320:F1093-F1105. [PMID: 33843272 PMCID: PMC8285653 DOI: 10.1152/ajprenal.00487.2020] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2020] [Revised: 04/05/2021] [Accepted: 04/05/2021] [Indexed: 01/13/2023] Open
Abstract
Hypertension and diabetes are the greatest factors influencing the progression of chronic kidney disease (CKD). Investigation into the role of nephron number in CKD alone or with hypertension has revealed a strong inverse relationship between the two; however, not much is known about the connection between nephron number and diabetic kidney disease. The heterogeneous stock-derived model of unilateral renal agenesis (HSRA) rat, a novel model of nephron deficiency, provides a unique opportunity to study the association between nephron number and hypertension and diabetes on CKD. HSRA rats exhibit failure of one kidney to develop in 50-75% of offspring, whereas the remaining offspring are born with two kidneys. Rats born with one kidney (HSRA-S) develop significant renal injury with age compared with two-kidney littermates (HSRA-C). The induction of hypertension as a secondary stressor leads to significantly more renal injury in HSRA-S compared with HSRA-C rats and nephrectomized HSRA-C (HSRA-UNX) rats. The present study sought to address the hypothesis that nephron deficiency in the HSRA rat would hasten renal injury in the presence of a secondary stressor of hyperglycemia. HSRA animals did not exhibit diabetes-related traits at any age; thus, streptozotocin (STZ) was used to induce hyperglycemia in HSRA-S, HSRA-C, and HSRA-UNX rats. STZ- and vehicle-treated animals were followed for 15 wk. STZ-treated animals developed robust hyperglycemia, but in contrast to the response to hypertension, neither HSRA-S nor HSRA-UNX animals developed proteinuria compared with vehicle treatment. In total, our data indicate that hyperglycemia from STZ alone does not have a significant impact on the onset or progression of injury in young one-kidney HSRA animals.NEW & NOTEWORTHY The HSRA rat, a novel model of nephron deficiency, provides a unique opportunity to study the association between nephron number and confounding cardiovascular complications that impact kidney health. Although hypertension was previously shown to exacerbate renal injury in young HSRA animals, diabetic hyperglycemia did not lead to worse renal injury, suggesting that nephron number has limited impact on kidney injury, at least in this model.
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Affiliation(s)
- Meredith B Cobb
- Department of Pharmacology and Toxicology, University of Mississippi Medical Center, Jackson, Mississippi
| | - Wenjie Wu
- Department of Pharmacology and Toxicology, University of Mississippi Medical Center, Jackson, Mississippi
| | - Esinam M Attipoe
- Department of Pharmacology and Toxicology, University of Mississippi Medical Center, Jackson, Mississippi
| | - Ashley C Johnson
- Department of Pharmacology and Toxicology, University of Mississippi Medical Center, Jackson, Mississippi
| | - Michael R Garrett
- Department of Pharmacology and Toxicology, University of Mississippi Medical Center, Jackson, Mississippi
- Department of Medicine (Nephrology), University of Mississippi Medical Center, Jackson, Mississippi
- Department of Pediatrics (Genetics), University of Mississippi Medical Center, Jackson, Mississippi
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25
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Singh AK, Kolligundla LP, Francis J, Pasupulati AK. Detrimental effects of hypoxia on glomerular podocytes. J Physiol Biochem 2021; 77:193-203. [PMID: 33835424 DOI: 10.1007/s13105-021-00788-y] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2020] [Accepted: 01/11/2021] [Indexed: 12/19/2022]
Abstract
Hypoxia-inducible factor1 (HIF1) plays a pivotal role in ensuring cells adapt to low-oxygen conditions. Depletion of oxygen, a co-substrate during hydroxylation of prolyl (P402 and P564) residues of HIF1⍺, evades HIF1⍺ ubiquitination and enables its dimerization with HIF1β to mediate global transcriptional response to hypoxia. Though HIF1 is largely considered eliciting a protective role during physiological or pathological hypoxia or ischemia, elevated HIF1 during chronic hypoxia contributes to glomerular diseases' pathology and proteinuria. The glomerulus is responsible for renal permselectivity and excretion of ultra-filtrated urine. Podocytes are the glomerulus' major cell types and are instrumental for glomerular filtration, permselectivity, and glomerular basement membrane maintenance. Podocyte injury is expected to impair the efficiency of glomerular filtration and manifestation of glomerulosclerosis and proteinuria. Accumulated evidence suggests that podocytes are susceptible to various insults during chronic hypoxia, including podocyte EMT, slit-diaphragm dysfunction, foot process effacement, and cytoskeletal derangement due to accumulation of HIF1. This review discusses how hypoxia/HIF1 signaling regulates various features and function of podocytes during exposure to chronic hypoxia or inducing HIF1 by various chemical modulators.
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Affiliation(s)
- Ashish K Singh
- Department of Biochemistry, School of Life Sciences, University of Hyderabad, Hyderabad, India
| | - Lakshmi P Kolligundla
- Department of Biochemistry, School of Life Sciences, University of Hyderabad, Hyderabad, India
| | - Justus Francis
- Department of Biochemistry, School of Life Sciences, University of Hyderabad, Hyderabad, India
| | - Anil K Pasupulati
- Department of Biochemistry, School of Life Sciences, University of Hyderabad, Hyderabad, India.
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26
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Horton WB, Barrett EJ. Microvascular Dysfunction in Diabetes Mellitus and Cardiometabolic Disease. Endocr Rev 2021; 42:29-55. [PMID: 33125468 PMCID: PMC7846151 DOI: 10.1210/endrev/bnaa025] [Citation(s) in RCA: 116] [Impact Index Per Article: 38.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/14/2020] [Indexed: 02/07/2023]
Abstract
This review takes an inclusive approach to microvascular dysfunction in diabetes mellitus and cardiometabolic disease. In virtually every organ, dynamic interactions between the microvasculature and resident tissue elements normally modulate vascular and tissue function in a homeostatic fashion. This regulation is disordered by diabetes mellitus, by hypertension, by obesity, and by dyslipidemia individually (or combined in cardiometabolic disease), with dysfunction serving as an early marker of change. In particular, we suggest that the familiar retinal, renal, and neural complications of diabetes mellitus are late-stage manifestations of microvascular injury that begins years earlier and is often abetted by other cardiometabolic disease elements (eg, hypertension, obesity, dyslipidemia). We focus on evidence that microvascular dysfunction precedes anatomic microvascular disease in these organs as well as in heart, muscle, and brain. We suggest that early on, diabetes mellitus and/or cardiometabolic disease can each cause reversible microvascular injury with accompanying dysfunction, which in time may or may not become irreversible and anatomically identifiable disease (eg, vascular basement membrane thickening, capillary rarefaction, pericyte loss, etc.). Consequences can include the familiar vision loss, renal insufficiency, and neuropathy, but also heart failure, sarcopenia, cognitive impairment, and escalating metabolic dysfunction. Our understanding of normal microvascular function and early dysfunction is rapidly evolving, aided by innovative genetic and imaging tools. This is leading, in tissues like the retina, to testing novel preventive interventions at early, reversible stages of microvascular injury. Great hope lies in the possibility that some of these interventions may develop into effective therapies.
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Affiliation(s)
- William B Horton
- Division of Endocrinology and Metabolism, Department of Medicine
| | - Eugene J Barrett
- Division of Endocrinology and Metabolism, Department of Medicine.,Department of Pharmacology, University of Virginia School of Medicine, Charlottesville, Virginia
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27
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Agarwal S, Sudhini YR, Reiser J, Altintas MM. From Infancy to Fancy: A Glimpse into the Evolutionary Journey of Podocytes in Culture. KIDNEY360 2020; 2:385-397. [PMID: 35373019 PMCID: PMC8740988 DOI: 10.34067/kid.0006492020] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/30/2020] [Accepted: 12/22/2020] [Indexed: 02/04/2023]
Abstract
Podocytes are critical components of the filtration barrier and responsible for maintaining healthy kidney function. An assault on podocytes is generally associated with progression of chronic glomerular diseases. Therefore, podocyte pathophysiology is a favorite research subject for nephrologists. Despite this, podocyte research has lagged because of the unavailability of techniques for culturing such specialized cells ex vivo in quantities that are adequate for mechanistic studies. In recent years, this problem was circumvented by the efforts of researchers, who successfully developed several in vitro podocyte cell culture model systems that paved the way for incredible discoveries in the field of nephrology. This review sets us on a journey that provides a comprehensive insight into the groundbreaking breakthroughs and novel technologic advances made in the field of podocyte cell culture so far, beginning from its inception, evolution, and progression. In this study, we also describe in detail the pros and cons of different models that are being used to culture podocytes. Our extensive and exhaustive deliberation on the status of podocyte cell culture will facilitate researchers to choose wisely an appropriate model for their own research to avoid potential pitfalls in the future.
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28
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Prikryl P, Satrapova V, Frydlova J, Hruskova Z, Zima T, Tesar V, Vokurka M. Mass spectrometry-based proteomic exploration of the small urinary extracellular vesicles in ANCA-associated vasculitis in comparison with total urine. J Proteomics 2020; 233:104067. [PMID: 33307252 DOI: 10.1016/j.jprot.2020.104067] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2020] [Revised: 09/11/2020] [Accepted: 11/29/2020] [Indexed: 01/07/2023]
Abstract
ANCA-associated vasculitis (AAV) is a rare, but potentially severe autoimmune disease, even nowadays displaying increased mortality and morbidity. Finding early biomarkers of activity and prognosis is thus very important. Small extracellular vesicles (EVs) isolated from urine can be considered as a non-invasive source of biomarkers. We evaluated several protocols for urinary EV isolation. To eliminate contaminating non-vesicular proteins due to AAV associated proteinuria we used proteinase K treatment. We investigated the differences in proteomes of small EVs of patients with AAV compared to healthy controls by label-free LC-MS/MS. In parallel, we performed an analogous proteomic analysis of urine samples from identical patients. The study results showed significant differences and similarities in both EV and urine proteome, the latter one being highly affected by proteinuria. Using bioinformatics tools we explored differentially changed proteins and their related pathways with a focus on the pathophysiology of AAV. Our findings indicate significant regulation of Golgi enzymes, such as MAN1A1, which can be involved in T cell activation by N-glycans glycosylation and may thus play a key role in pathogenesis and diagnosis of AAV. SIGNIFICANCE: The present study explores for the first time the changes in proteomes of small extracellular vesicles and urine of patients with renal ANCA-associated vasculitis compared to healthy controls by label-free LC-MS/MS. Isolation of vesicles from proteinuric urine samples has been modified to minimize contamination by plasma proteins and to reduce co-isolation of extraluminal proteins. Differentially changed proteins and their related pathways with a role in the pathophysiology of AAV were described and discussed. The results could be helpful for the research of potential biomarkers in renal vasculitis associated with ANCA.
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Affiliation(s)
- Petr Prikryl
- Institute of Pathological Physiology, First Faculty of Medicine, Charles University, Prague, Czech Republic
| | - Veronika Satrapova
- Department of Nephrology, First Faculty of Medicine, Charles University and General University Hospital, Prague, Czech Republic
| | - Jana Frydlova
- Institute of Pathological Physiology, First Faculty of Medicine, Charles University, Prague, Czech Republic
| | - Zdenka Hruskova
- Department of Nephrology, First Faculty of Medicine, Charles University and General University Hospital, Prague, Czech Republic
| | - Tomas Zima
- Institute of Clinical Biochemistry and Laboratory Diagnostics, First Faculty of Medicine, Charles University and General University Hospital, Prague, Czech Republic
| | - Vladimir Tesar
- Department of Nephrology, First Faculty of Medicine, Charles University and General University Hospital, Prague, Czech Republic
| | - Martin Vokurka
- Institute of Pathological Physiology, First Faculty of Medicine, Charles University, Prague, Czech Republic.
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29
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Tian X, Inoue K, Zhang Y, Wang Y, Sperati CJ, Pedigo CE, Zhao T, Yan M, Groener M, Moledina DG, Ebenezer K, Li W, Zhang Z, Liebermann DA, Greene L, Greer P, Parikh CR, Ishibe S. Inhibiting calpain 1 and 2 in cyclin G associated kinase-knockout mice mitigates podocyte injury. JCI Insight 2020; 5:142740. [PMID: 33208557 PMCID: PMC7710277 DOI: 10.1172/jci.insight.142740] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2020] [Accepted: 10/08/2020] [Indexed: 12/27/2022] Open
Abstract
Evidence for reduced expression of cyclin G associated kinase (GAK) in glomeruli of patients with chronic kidney disease was observed in the Nephroseq human database, and GAK was found to be associated with the decline in kidney function. To examine the role of GAK, a protein that functions to uncoat clathrin during endocytosis, we generated podocyte-specific Gak-knockout mice (Gak-KO), which developed progressive proteinuria and kidney failure with global glomerulosclerosis. We isolated glomeruli from the mice carrying the mutation to perform messenger RNA profiling and unearthed evidence for dysregulated podocyte calpain protease activity as an important contributor to progressive podocyte damage. Treatment with calpain inhibitor III specifically inhibited calpain-1/-2 activities, mitigated the degree of proteinuria and glomerulosclerosis, and led to a striking increase in survival in the Gak-KO mice. Podocyte-specific deletion of Capns1, essential for calpain-1 and calpain-2 activities, also improved proteinuria and glomerulosclerosis in Gak-KO mice. Increased podocyte calpain activity-mediated proteolysis of IκBα resulted in increased NF-κB p65-induced expression of growth arrest and DNA-damage-inducible 45 beta in the Gak-KO mice. Our results suggest that loss of podocyte-associated Gak induces glomerular injury secondary to calcium dysregulation and aberrant calpain activation, which when inhibited, can provide a protective role.
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MESH Headings
- Animals
- Calpain/antagonists & inhibitors
- Diabetic Nephropathies/etiology
- Diabetic Nephropathies/metabolism
- Diabetic Nephropathies/pathology
- Diabetic Nephropathies/therapy
- Female
- Glomerulosclerosis, Focal Segmental/etiology
- Glomerulosclerosis, Focal Segmental/metabolism
- Glomerulosclerosis, Focal Segmental/pathology
- Glomerulosclerosis, Focal Segmental/therapy
- Humans
- Intracellular Signaling Peptides and Proteins/genetics
- Intracellular Signaling Peptides and Proteins/metabolism
- Male
- Mice
- Mice, Inbred C57BL
- Mice, Knockout
- Podocytes/metabolism
- Podocytes/pathology
- Protein Serine-Threonine Kinases/genetics
- Protein Serine-Threonine Kinases/metabolism
- Protein Serine-Threonine Kinases/physiology
- Renal Insufficiency, Chronic/etiology
- Renal Insufficiency, Chronic/metabolism
- Renal Insufficiency, Chronic/pathology
- Renal Insufficiency, Chronic/therapy
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Affiliation(s)
- Xuefei Tian
- Department of Internal Medicine, Yale University School of Medicine, New Haven, Connecticut, USA
| | - Kazunori Inoue
- Department of Internal Medicine, Yale University School of Medicine, New Haven, Connecticut, USA
| | - Yan Zhang
- State Key Laboratory of Organ Failure Research, Southern Medical University, Nanfang Hospital, Guangzhou, China
- Center for Bioinformatics, School of Basic Medical Sciences, Southern Medical University, Guangzhou, China
| | - Ying Wang
- Department of Internal Medicine, Yale University School of Medicine, New Haven, Connecticut, USA
| | - C. John Sperati
- Division of Nephrology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Christopher E. Pedigo
- Department of Internal Medicine, Yale University School of Medicine, New Haven, Connecticut, USA
| | - Tingting Zhao
- Department of Internal Medicine, Yale University School of Medicine, New Haven, Connecticut, USA
| | - Meihua Yan
- Department of Internal Medicine, Yale University School of Medicine, New Haven, Connecticut, USA
| | - Marwin Groener
- Department of Internal Medicine, Yale University School of Medicine, New Haven, Connecticut, USA
| | - Dennis G. Moledina
- Department of Internal Medicine, Yale University School of Medicine, New Haven, Connecticut, USA
| | - Karen Ebenezer
- Department of Internal Medicine, Yale University School of Medicine, New Haven, Connecticut, USA
| | - Wei Li
- Department of Internal Medicine, Yale University School of Medicine, New Haven, Connecticut, USA
| | - Zhenhai Zhang
- State Key Laboratory of Organ Failure Research, Southern Medical University, Nanfang Hospital, Guangzhou, China
- Center for Bioinformatics, School of Basic Medical Sciences, Southern Medical University, Guangzhou, China
| | - Dan A. Liebermann
- Fels Institute of Cancer Research and Molecular Biology and Department of Medical Genetics and Molecular Biochemistry, Lewis Katz School of Medicine, Temple University, Philadelphia, Pennsylvania USA
| | - Lois Greene
- Laboratory of Cell Biology, National Heart, Lung, and Blood Institute, NIH, Bethesda, Maryland, USA
| | - Peter Greer
- Queen’s Cancer Research Institute, Kingston, Ontario, Canada
| | - Chirag R. Parikh
- Division of Nephrology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Shuta Ishibe
- Department of Internal Medicine, Yale University School of Medicine, New Haven, Connecticut, USA
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30
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Abdallah M, Nagarajan S, Martin M, Tamer M, Faour WH, Bassil M, Cuisinier FJG, Gergely C, Varga B, Pall O, Miele P, Balme S, El Tahchi M, Bechelany M. Enhancement of Podocyte Attachment on Polyacrylamide Hydrogels with Gelatin-Based Polymers. ACS APPLIED BIO MATERIALS 2020; 3:7531-7539. [PMID: 35019494 DOI: 10.1021/acsabm.0c00734] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Biological activities of cells such as survival and differentiation processes are mainly maintained by a specific extracellular matrix (ECM). Hydrogels have recently been employed successfully in tissue engineering applications. In particular, scaffolds made of gelatin methacrylate-based hydrogels (GelMA) showed great potential due to their biocompatibility, biofunctionality, and low mechanical strength. The development of a hydrogel having tunable and appropriate mechanical properties as well as chemical and biological cues was the aim of this work. A synthetic and biological hybrid hydrogel was developed to mimic the biological and mechanical properties of native ECM. A combination of gelatin methacrylate and acrylamide (GelMA-AAm)-based hydrogels was studied, and it showed tunable mechanical properties upon changing the polymer concentrations. Different GelMA-AAm samples were prepared and studied by varying the concentrations of GelMA and AAm (AAm2.5% + GelMA3%, AAm5% + GelMA3%, and AAm5% + GelMA5%). The swelling behavior, biodegradability, physicochemical and mechanical properties of GelMA-AAm were also characterized. The results showed a variation of swelling capability and a tunable elasticity ranging from 4.03 to 24.98 kPa depending on polymer concentrations. Moreover, the podocyte cell morphology, cytoskeleton reorganization and differentiation were evaluated as a function of GelMA-AAm mechanical properties. We concluded that the AAm2.5% + GelMA3% hydrogel sample having an elasticity of 4.03 kPa can mimic the native kidney glomerular basement membrane (GBM) elasticity and allow podocyte cell attachment without the functionalization of the gel surface with adhesion proteins compared to synthetic hydrogels (PAAm). This work will further enhance the knowledge of the behavior of podocyte cells to understand their biological properties in both healthy and diseased states.
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Affiliation(s)
- Maya Abdallah
- Institut Européen des Membranes, IEM UMR 5635, Univ Montpellier, ENSCM, CNRS, Montpellier 34095, France
| | - Sakthivel Nagarajan
- Institut Européen des Membranes, IEM UMR 5635, Univ Montpellier, ENSCM, CNRS, Montpellier 34095, France
| | - Marta Martin
- Laboratoire Charles Coulomb, Université de Montpellier, CNRS, Montpellier 34095, France
| | - Marleine Tamer
- Institut Européen des Membranes, IEM UMR 5635, Univ Montpellier, ENSCM, CNRS, Montpellier 34095, France
| | - Wissam H Faour
- Gilbert and Rose-Marie Chagoury School of Medicine, Lebanese American University, Byblos, Lebanon
| | - Maria Bassil
- Faculty of Sciences II, Department of Physics, Biomaterials and Intelligent Materials Research Laboratory (LBMI), Lebanese University, Beirut, Lebanon
| | - Frederic J G Cuisinier
- Laboratoire de Bioingénierie et Nanosciences, Université de Montpellier, Montpellier, France
| | - Csilla Gergely
- Laboratoire Charles Coulomb, Université de Montpellier, CNRS, Montpellier 34095, France
| | - Bela Varga
- Laboratoire Charles Coulomb, Université de Montpellier, CNRS, Montpellier 34095, France
| | - Orsolya Pall
- Laboratoire de Bioingénierie et Nanosciences, Université de Montpellier, Montpellier, France
| | - Philippe Miele
- Institut Européen des Membranes, IEM UMR 5635, Univ Montpellier, ENSCM, CNRS, Montpellier 34095, France
| | - Sebastien Balme
- Institut Européen des Membranes, IEM UMR 5635, Univ Montpellier, ENSCM, CNRS, Montpellier 34095, France
| | - Mario El Tahchi
- Faculty of Sciences II, Department of Physics, Biomaterials and Intelligent Materials Research Laboratory (LBMI), Lebanese University, Beirut, Lebanon
| | - Mikhael Bechelany
- Institut Européen des Membranes, IEM UMR 5635, Univ Montpellier, ENSCM, CNRS, Montpellier 34095, France
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Wang Y, Eng DG, Kaverina NV, Loretz CJ, Koirala A, Akilesh S, Pippin JW, Shankland SJ. Global transcriptomic changes occur in aged mouse podocytes. Kidney Int 2020; 98:1160-1173. [PMID: 32592814 PMCID: PMC7606654 DOI: 10.1016/j.kint.2020.05.052] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2020] [Revised: 05/17/2020] [Accepted: 05/28/2020] [Indexed: 01/15/2023]
Abstract
Glomerular podocytes undergo structural and functional changes with advanced age, that increase susceptibility of aging kidneys to worse outcomes following superimposed glomerular diseases. To delineate transcriptional changes in podocytes in aged mice, RNA-seq was performed on isolated populations of reporter-labeled (tdTomato) podocytes from multiple young (two to three months) and advanced aged mice (22 to 24 months, equivalent to 70 plus year old humans). Of the 2,494 differentially expressed genes, 1,219 were higher and 1,275 were lower in aged podocytes. Pathway enrichment showed that major biological processes increased in aged podocytes included immune responses, non-coding RNA metabolism, gene silencing and MAP kinase signaling. Conversely, aged podocytes showed downregulation of developmental, morphogenesis and metabolic processes. Canonical podocyte marker gene expression decreased in aged podocytes, with increases in apoptotic and senescence genes providing a mechanism for the progressive loss of podocytes seen with aging. In addition, we revealed aberrations in the podocyte autocrine signaling network, identified the top transcription factors perturbed in aged podocytes, and uncovered candidate gene modulations that might promote healthy aging in podocytes. The transcriptional signature of aging is distinct from other kidney diseases. Thus, our study provides insights into biomarker discovery and molecular targeting of the aging process itself within podocytes.
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Affiliation(s)
- Yuliang Wang
- Paul G. Allen School of Computer Science and Engineering, University of Washington, Seattle, Washington, USA; Institute for Stem Cell & Regenerative Medicine, University of Washington, Seattle, Washington, USA
| | - Diana G Eng
- Division of Nephrology, University of Washington, Seattle, Washington, USA
| | - Natalya V Kaverina
- Division of Nephrology, University of Washington, Seattle, Washington, USA
| | - Carol J Loretz
- Division of Nephrology, University of Washington, Seattle, Washington, USA
| | - Abbal Koirala
- Division of Nephrology, University of Washington, Seattle, Washington, USA
| | - Shreeram Akilesh
- Department of Pathology, University of Washington, Seattle, Washington, USA
| | - Jeffrey W Pippin
- Division of Nephrology, University of Washington, Seattle, Washington, USA
| | - Stuart J Shankland
- Division of Nephrology, University of Washington, Seattle, Washington, USA.
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Kawachi H, Fukusumi Y. New insight into podocyte slit diaphragm, a therapeutic target of proteinuria. Clin Exp Nephrol 2020; 24:193-204. [PMID: 32020343 PMCID: PMC7040068 DOI: 10.1007/s10157-020-01854-3] [Citation(s) in RCA: 64] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2019] [Accepted: 01/15/2020] [Indexed: 12/26/2022]
Abstract
Dysfunction of slit diaphragm, a cell–cell junction of glomerular podocytes, is involved in the development of proteinuria in several glomerular diseases. Slit diaphragm should be a target of a novel therapy for proteinuria. Nephrin, NEPH1, P-cadherin, FAT, and ephrin-B1 were reported to be extracellular components forming a molecular sieve of the slit diaphragm. Several cytoplasmic proteins such as ZO-1, podocin, CD2AP, MAGI proteins and Par-complex molecules were identified as scaffold proteins linking the slit diaphragm to the cytoskeleton. In this article, new insights into these molecules and the pathogenic roles of the dysfunction of these molecules were introduced. The slit diaphragm functions not only as a barrier but also as a signaling platform transfer the signal to the inside of the cell. For maintaining the slit diaphragm function properly, the phosphorylation level of nephrin is strictly regulated. The recent studies on the signaling pathway from nephrin, NEPH1, and ephrin-B1 were reviewed. Although the mechanism regulating the function of the slit diaphragm had remained unclear, recent studies revealed TRPC6 and angiotensin II-regulating mechanisms play a critical role in regulating the barrier function of the slit diaphragm. In this review, recent investigations on the regulation of the slit diaphragm function were reviewed, and a strategy for the establishment of a novel therapy for proteinuria was proposed.
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Affiliation(s)
- Hiroshi Kawachi
- Department of Cell Biology, Kidney Research Center, Niigata University Graduate School of Medical and Dental Sciences, 1-757 Asahimachi-dori, Chuo-ku, Niigata, 951-8510, Japan.
| | - Yoshiyasu Fukusumi
- Department of Cell Biology, Kidney Research Center, Niigata University Graduate School of Medical and Dental Sciences, 1-757 Asahimachi-dori, Chuo-ku, Niigata, 951-8510, Japan
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33
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Eftekhari A, Vahed SZ, Kavetskyy T, Rameshrad M, Jafari S, Chodari L, Hosseiniyan SM, Derakhshankhah H, Ahmadian E, Ardalan M. Cell junction proteins: Crossing the glomerular filtration barrier in diabetic nephropathy. Int J Biol Macromol 2020; 148:475-482. [PMID: 31962072 DOI: 10.1016/j.ijbiomac.2020.01.168] [Citation(s) in RCA: 45] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2019] [Revised: 01/17/2020] [Accepted: 01/17/2020] [Indexed: 12/20/2022]
Abstract
Diabetic nephropathy as a deleterious complication of diabetes mellitus and an important cause of end-stage renal failure is characterized by changes in the molecular and cellular levels. Cell-cell communication via the gap and tight junctions are involved in the pathogenesis of diseases such as diabetes and kidney failure. Studying cell junctions including gap junctions, tight junctions, and anchoring junctions within the nephron can be used as an early sign of diabetic nephropathy. Furthermore, cell junctions may be an upcoming target by pharmacological methods to improve treatments of diabetic nephropathy and pave the way to introduce promising therapeutic strategies based on cell-cell communications effects and its translation into clinical studies for the treatment of diabetic nephropathy.
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Affiliation(s)
- Aziz Eftekhari
- Pharmacology and Toxicology Department, Maragheh University of Medical Sciences, Maragheh, Iran
| | | | - Taras Kavetskyy
- Drohobych Ivan Franko State Pedagogical University, Drohobych, Ukraine; The John Paul II Catholic University of Lublin, Lublin, Poland
| | - Maryam Rameshrad
- Natural Products and Medicinal Plants Research Center, North Khorasan University of Medical Sciences, Bojnurd, Iran
| | - Samira Jafari
- Pharmaceutical Sciences Research Center, Health Institute, Kermanshah University of Medical Sciences, Kermanshah, Iran
| | - Leila Chodari
- Physiology Department, Faculty of Medicine, Urmia University of Medical Sciences, Urmia, Iran
| | | | - Hossein Derakhshankhah
- Pharmaceutical Sciences Research Center, Health Institute, Kermanshah University of Medical Sciences, Kermanshah, Iran
| | - Elham Ahmadian
- Kidney Research Center, Tabriz University of Medical Sciences, Tabriz, Iran; Students Research Committee, Tabriz University of Medical Sciences, Tabriz, Iran.
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Takamura S, Fukusumi Y, Zhang Y, Narita I, Kawachi H. Partitioning-Defective-6-Ephrin-B1 Interaction Is Regulated by Nephrin-Mediated Signal and Is Crucial in Maintaining Slit Diaphragm of Podocyte. THE AMERICAN JOURNAL OF PATHOLOGY 2019; 190:333-346. [PMID: 31837290 DOI: 10.1016/j.ajpath.2019.10.015] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/08/2019] [Revised: 09/04/2019] [Accepted: 10/18/2019] [Indexed: 01/15/2023]
Abstract
Ephrin-B1 plays a critical role at slit diaphragm. Partitioning-defective (Par)-6 is down-regulated in podocyte of ephrin-B1 knockout mouse, suggesting that Par-6 is associated with ephrin-B1. Par polarity complex, consisting of Par-6, Par-3, and atypical protein kinase C, is essential for tight junction formation. In this study, the expression of Par-6 was analyzed in the normal and nephrotic syndrome model rats, and the molecular association of Par-6, Par-3, ephrin-B1, and nephrin was assessed with the human embryonic kidney 293 cell expression system. Par-6 was concentrated at slit diaphragm. Par 6 interacted with ephrin-B1 but not with nephrin, and Par-3 interacted with nephrin but not with ephrin-B1. The complexes of Par-6-ephrin-B1 and Par-3-nephrin were linked via extracellular sites of ephrin-B1 and nephrin. The Par-6-ephrin-B1 complex was delinked from the Par-3-nephrin complex, and Par-6 and ephrin-B1 were clearly down-regulated already at early phase of nephrotic model. The alteration of Par-6/ephrin-B1 advanced that of Par-3/nephrin. Stimulation to nephrin phosphorylated not only nephrin but also ephrin-B1, and consequently inhibited the interaction between ephrin-B1 and Par-6. Par-6 appeared at presumptive podocyte of early developmental stage and moved to basal area at capillary loop stage to participate in slit diaphragm formation at the final stage. Par-6-ephrin-B1 interaction is crucial for formation and maintenance of slit diaphragm of podocyte.
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Affiliation(s)
- Sayuri Takamura
- Department of Cell Biology, Kidney Research Center, Niigata University Graduate School of Medical and Dental Sciences, Niigata, Japan; Division of Clinical Nephrology and Rheumatology, Kidney Research Center, Niigata University Graduate School of Medical and Dental Sciences, Niigata, Japan
| | - Yoshiyasu Fukusumi
- Department of Cell Biology, Kidney Research Center, Niigata University Graduate School of Medical and Dental Sciences, Niigata, Japan
| | - Ying Zhang
- Department of Cell Biology, Kidney Research Center, Niigata University Graduate School of Medical and Dental Sciences, Niigata, Japan
| | - Ichiei Narita
- Division of Clinical Nephrology and Rheumatology, Kidney Research Center, Niigata University Graduate School of Medical and Dental Sciences, Niigata, Japan
| | - Hiroshi Kawachi
- Department of Cell Biology, Kidney Research Center, Niigata University Graduate School of Medical and Dental Sciences, Niigata, Japan.
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Ectopic expression of CLDN2 in podocytes is associated with childhood onset nephrotic syndrome. Pediatr Res 2019; 86:485-491. [PMID: 31086291 DOI: 10.1038/s41390-019-0423-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/05/2019] [Revised: 04/19/2019] [Accepted: 04/24/2019] [Indexed: 11/08/2022]
Abstract
BACKGROUND Animal models of nephrotic syndrome (NS) revealed that tight junction (TJ)-like structures are generated together with a concomitant decrease in slit diaphragms (SDs). Claudins (CLDNs) are capable of forming TJ strands and thereby the backbone of TJs. We showed the ectopic expression of CLDN2 in podocytes in pediatric NS, and detected its localization. METHODS Renal frozen specimens were obtained by biopsy from 49 pediatric patients: 21 subjects with MCD, 18 with FSGS, and 10 with IgA nephritis (IgA-N). CLDN2 expression was observed by immunohistochemistry and the CLDN2-positive area was calculated. Moreover, its localization was detected using immunoelectron microscopy. RESULTS CLDN2 is ectopically detected in cases with MCD and FSGS before remission. The CLDN2-stained region in MCD and FSGS glomeruli before remission was significantly greater than that after remission as well as in IgA-N patients. Immunoelectron microscopy revealed that CLDN2 was concentrated along newly formed TJs in podocytes. CONCLUSION The same pathological findings in terms of ectopic CLDN2 expression in podocytes were shown in cases with MCD and FSGS before remission. Immunofluorescence and immunoelectron studies of CLDN2 appear to afford a powerful tool for the diagnosis of primary NS. In addition, CLDN2 expression level may be related to disease status.
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36
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Rachubik P, Piwkowska A. The role of vasodilator‐stimulated phosphoprotein in podocyte functioning. Cell Biol Int 2019; 43:1092-1101. [DOI: 10.1002/cbin.11149] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2018] [Accepted: 04/06/2019] [Indexed: 12/20/2022]
Affiliation(s)
- Patrycja Rachubik
- Laboratory of Molecular and Cellular Nephrology, Mossakowski Medical Research CentrePolish Academy of Sciences Wita Stwosza 63, 80‐308 Gdańsk Poland
| | - Agnieszka Piwkowska
- Laboratory of Molecular and Cellular Nephrology, Mossakowski Medical Research CentrePolish Academy of Sciences Wita Stwosza 63, 80‐308 Gdańsk Poland
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Andrikou C, Thiel D, Ruiz-Santiesteban JA, Hejnol A. Active mode of excretion across digestive tissues predates the origin of excretory organs. PLoS Biol 2019; 17:e3000408. [PMID: 31356592 PMCID: PMC6687202 DOI: 10.1371/journal.pbio.3000408] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2019] [Revised: 08/08/2019] [Accepted: 07/12/2019] [Indexed: 11/21/2022] Open
Abstract
Most bilaterian animals excrete toxic metabolites through specialized organs, such as nephridia and kidneys, which share morphological and functional correspondences. In contrast, excretion in non-nephrozoans is largely unknown, and therefore the reconstruction of ancestral excretory mechanisms is problematic. Here, we investigated the excretory mode of members of the Xenacoelomorpha, the sister group to Nephrozoa, and Cnidaria, the sister group to Bilateria. By combining gene expression, inhibitor experiments, and exposure to varying environmental ammonia conditions, we show that both Xenacoelomorpha and Cnidaria are able to excrete across digestive-associated tissues. However, although the cnidarian Nematostella vectensis seems to use diffusion as its main excretory mode, the two xenacoelomorphs use both active transport and diffusion mechanisms. Based on these results, we propose that digestive-associated tissues functioned as excretory sites before the evolution of specialized organs in nephrozoans. We conclude that the emergence of a compact, multiple-layered bilaterian body plan necessitated the evolution of active transport mechanisms, which were later recruited into the specialized excretory organs.
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Affiliation(s)
- Carmen Andrikou
- Sars International Centre for Marine Molecular Biology, University of Bergen, Bergen, Norway
| | - Daniel Thiel
- Sars International Centre for Marine Molecular Biology, University of Bergen, Bergen, Norway
| | | | - Andreas Hejnol
- Sars International Centre for Marine Molecular Biology, University of Bergen, Bergen, Norway
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38
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Nakuluri K, Mukhi D, Mungamuri SK, Pasupulati AK. Stabilization of hypoxia-inducible factor 1α by cobalt chloride impairs podocyte morphology and slit-diaphragm function. J Cell Biochem 2019; 120:7667-7678. [PMID: 30387200 DOI: 10.1002/jcb.28041] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2018] [Accepted: 10/15/2018] [Indexed: 01/24/2023]
Abstract
Glomerular podocytes are the major components of the renal filtration barrier, and altered podocyte permselectivity is a key event in the pathogenesis of proteinuric conditions. Clinical conditions such as ischemia and sleep apnea and extreme physiological conditions such as high-altitude sickness are presented with renal hypoxia and are associated with significant proteinuria. Hypoxia is considered as an etiological factor in the progression of acute renal injury. A sustained increase in hypoxia-inducible factor 1α (HIF1α) is a major adaptive stimulus to the hypoxic conditions. Although the temporal association between hypoxia and proteinuria is known, the mechanism by which hypoxia elicits proteinuria remains to be investigated. Furthermore, stabilization of HIF1α is being considered as a therapeutic option to treat anemia in patients with chronic kidney disease. Therefore, in this study, we induced stabilization of HIF1α in glomerular regions in vivo and in podocytes in vitro upon exposure to cobalt chloride. The elevated HIF1α expression is concurrence with diminished expression of nephrin and podocin, podocyte foot-processes effacement, and significant proteinuria. Podocytes exposed to cobalt chloride lost their arborized morphology and cell-cell connections and also displayed cytoskeletal derangements. Elevation in expression of HIF1α is in concomitance with loss of nephrin and podocin in patients with diabetic nephropathy and chronic kidney disease. In summary, the current study suggests that HIF1α stabilization impairs podocyte function vis-à-vis glomerular permselectivity.
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Affiliation(s)
- Krishnamurthy Nakuluri
- Department of Biochemistry, School of Life Sciences, University of Hyderabad, Hyderabad, India
| | - Dhanunjay Mukhi
- Department of Biochemistry, School of Life Sciences, University of Hyderabad, Hyderabad, India
| | - Sathish Kumar Mungamuri
- Asian Health Care Foundation, Institute of Basic Sciences and Translational Research, Asian Institute of Gastroenterology, Hyderabad, India
| | - Anil Kumar Pasupulati
- Department of Biochemistry, School of Life Sciences, University of Hyderabad, Hyderabad, India
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Yu SMW, Nissaisorakarn P, Husain I, Jim B. Proteinuric Kidney Diseases: A Podocyte's Slit Diaphragm and Cytoskeleton Approach. Front Med (Lausanne) 2018; 5:221. [PMID: 30255020 PMCID: PMC6141722 DOI: 10.3389/fmed.2018.00221] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2018] [Accepted: 07/18/2018] [Indexed: 01/19/2023] Open
Abstract
Proteinuric kidney diseases are a group of disorders with diverse pathological mechanisms associated with significant losses of protein in the urine. The glomerular filtration barrier (GFB), comprised of the three important layers, the fenestrated glomerular endothelium, the glomerular basement membrane (GBM), and the podocyte, dictates that disruption of any one of these structures should lead to proteinuric disease. Podocytes, in particular, have long been considered as the final gatekeeper of the GFB. This specialized visceral epithelial cell contains a complex framework of cytoskeletons forming foot processes and mediate important cell signaling to maintain podocyte health. In this review, we will focus on slit diaphragm proteins such as nephrin, podocin, TRPC6/5, as well as cytoskeletal proteins Rho/small GTPases and synaptopodin and their respective roles in participating in the pathogenesis of proteinuric kidney diseases. Furthermore, we will summarize the potential therapeutic options targeting the podocyte to treat this group of kidney diseases.
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Affiliation(s)
- Samuel Mon-Wei Yu
- Department of Medicine, Jacobi Medical Center, Bronx, NY, United States
| | | | - Irma Husain
- Department of Medicine, James J. Peters VA Medical Center, Bronx, NY, United States
| | - Belinda Jim
- Department of Medicine, Jacobi Medical Center, Bronx, NY, United States.,Renal Division, Jacobi Medical Center, Bronx, NY, United States
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40
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Weng Z, Shang Y, Ji Z, Ye F, Lin L, Zhang R, Zhu J. Structural Basis of Highly Specific Interaction between Nephrin and MAGI1 in Slit Diaphragm Assembly and Signaling. J Am Soc Nephrol 2018; 29:2362-2371. [PMID: 30006415 PMCID: PMC6115659 DOI: 10.1681/asn.2017121275] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2017] [Accepted: 06/19/2018] [Indexed: 01/07/2023] Open
Abstract
BACKGROUND The slit diaphragm is a specialized adhesion junction between opposing podocytes, establishing the final filtration barrier that prevents passage of proteins from the capillary lumen into the urinary space. Nephrin, the key structural and signaling adhesion molecule expressed in the slit diaphragm, contains an evolutionally conserved, atypical PDZ-binding motif (PBM) reported to bind to a variety of proteins in the slit diaphragm. Several mutations in NPHS1 (the gene encoding nephrin) that result in nephrin lacking an intact PBM are associated with glomerular diseases. However, the molecular basis of nephrin-PBM-mediated protein complexes is still unclear. METHODS Using a combination of biochemic, biophysic, and cell biologic approaches, we systematically investigated the interactions between nephrin-PBM and PDZ domain-containing proteins in the slit diaphragm. RESULTS We found that nephrin-PBM specifically binds to one member of the membrane-associated guanylate kinase family of scaffolding proteins, MAGI1, but not to another, MAGI2. The complex structure of MAGI1-PDZ3/nephrin-PBM reveals that the Gly at the -3 position of nephrin-PBM is the determining feature for MAGI1-PDZ3 recognition, which sharply contrasts with the typical PDZ/PBM binding mode. A single gain-of-function mutation within MAGI2 enabled nephrin-PBM binding. In addition, using our structural analysis, we developed a highly efficient inhibitory peptide capable of specifically blocking the nephrin/MAGI1 interaction. CONCLUSIONS MAGI1 interacts with nephrin-PBM with exquisite specificity. A newly developed, potent inhibitory peptide that blocks this interaction may be useful for future functional investigations in vivo. Our findings also provide possible explanations for the diseases caused by NPHS1 mutations.
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Affiliation(s)
- Zhuangfeng Weng
- State Key Laboratory of Molecular Biology, Shanghai Science Research Center, Chinese Academy of Sciences Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Shanghai, China;,School of Life Science and Technology, ShanghaiTech University, Shanghai, China; and
| | - Yuan Shang
- Division of Life Science, State Key Laboratory of Molecular Neuroscience, and
| | - Zeyang Ji
- Division of Life Science, State Key Laboratory of Molecular Neuroscience, and
| | - Fei Ye
- Division of Life Science, State Key Laboratory of Molecular Neuroscience, and,Center of Systems Biology and Human Health, Hong Kong University of Science and Technology, Kowloon, Hong Kong, China
| | - Lin Lin
- State Key Laboratory of Molecular Biology, Shanghai Science Research Center, Chinese Academy of Sciences Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Shanghai, China
| | - Rongguang Zhang
- State Key Laboratory of Molecular Biology, Shanghai Science Research Center, Chinese Academy of Sciences Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Shanghai, China;,School of Life Science and Technology, ShanghaiTech University, Shanghai, China; and
| | - Jinwei Zhu
- State Key Laboratory of Molecular Biology, Shanghai Science Research Center, Chinese Academy of Sciences Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Shanghai, China
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41
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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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Kumar N, Liao TD, Romero CA, Maheshwari M, Peterson EL, Carretero OA. Thymosin β4 Deficiency Exacerbates Renal and Cardiac Injury in Angiotensin-II-Induced Hypertension. Hypertension 2018; 71:1133-1142. [PMID: 29632102 DOI: 10.1161/hypertensionaha.118.10952] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2018] [Revised: 02/13/2018] [Accepted: 03/13/2018] [Indexed: 11/16/2022]
Abstract
Thymosin β4 (Tβ4), a ubiquitous peptide, regulates several cellular processes that include cell morphology, wound healing, and inflammatory response. Administration of exogenous Tβ4 is protective in diabetic nephropathy and in a unilateral ureteral obstruction model. However, the role of endogenous Tβ4 in health and disease conditions remains unclear. To elucidate the pathophysiological role of endogenous Tβ4 in hypertension, we examined angiotensin-II (Ang-II)-induced renal and cardiac damage in Tβ4 knockout (Tβ4 KO) mice. Tβ4 KO and wild-type C57BL/6 mice were infused continuously for 6 weeks with either vehicle or Ang-II (980 ng/kg per minute). At baseline, Tβ4 deficiency did not affect renal and cardiac function. Systolic blood pressure in the Ang-II group was similar in wild-type and Tβ4 KO mice (wild-type Ang-II, 179.25±10.11 mm Hg; Tβ4 KO Ang-II, 169.81±6.54 mm Hg). Despite the similar systolic blood pressure after Ang-II infusion, Tβ4-deficient mice had dramatically increased albuminuria and decreased nephrin expression in the kidney (P<0.005). In the heart of Tβ4 KO mice, Ang-II reduced ejection fraction and shortening fraction (ejection fraction: wild-type Ang-II 77.95%±1.03%; Tβ4 KO Ang-II 62.58%±3.25%; P<0.005), which was accompanied by cardiac hypertrophy and left ventricular dilatation. In addition, renal and cardiac infiltration of CD68 macrophages, intercellular adhesion molecule-1, and total collagen content were increased after Ang-II infusion in Tβ4 KO mice (P<0.005). Overall, our data indicate that endogenous Tβ4 is crucial in preventing tissue injury from Ang-II-induced hypertension. This study gives new insights into the protective role of endogenous Tβ4 in hypertensive end-organ damage.
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Affiliation(s)
- Nitin Kumar
- From the Hypertension and Vascular Research Division, Department of Internal Medicine (N.K., T.-D.L., C.A.R., M.M., O.A.C.)
| | - Tang-Dong Liao
- From the Hypertension and Vascular Research Division, Department of Internal Medicine (N.K., T.-D.L., C.A.R., M.M., O.A.C.)
| | - Cesar A Romero
- From the Hypertension and Vascular Research Division, Department of Internal Medicine (N.K., T.-D.L., C.A.R., M.M., O.A.C.)
| | - Mani Maheshwari
- From the Hypertension and Vascular Research Division, Department of Internal Medicine (N.K., T.-D.L., C.A.R., M.M., O.A.C.)
| | - Edward L Peterson
- and Department of Public Health Sciences (E.L.P.), Henry Ford Hospital, Detroit, MI
| | - Oscar A Carretero
- From the Hypertension and Vascular Research Division, Department of Internal Medicine (N.K., T.-D.L., C.A.R., M.M., O.A.C.)
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Liu YC, Chun J. Prospects for Precision Medicine in Glomerulonephritis Treatment. Can J Kidney Health Dis 2018; 5:2054358117753617. [PMID: 29449955 PMCID: PMC5808958 DOI: 10.1177/2054358117753617] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2017] [Accepted: 11/12/2017] [Indexed: 02/06/2023] Open
Abstract
Background: Glomerulonephritis (GN) consists of a group of kidney diseases that are categorized based on shared histopathological features. The current classifications for GN make it difficult to distinguish the individual variability in presentation, disease progression, and response to treatment. GN is a significant cause of end-stage renal disease (ESRD), and improved therapies are desperately needed because current immunosuppressive therapies sometimes lack efficacy and can lead to significant toxicities. In recent years, the combination of high-throughput genetic approaches and technological advances has identified important regulators contributing to GN. Objectives: In this review, we summarize recent findings in podocyte biology and advances in experimental approaches that have opened the possibility of precision medicine in GN treatment. We provide an integrative basic science and clinical overview of new developments in GN research and the discovery of potential candidates for targeted therapies in GN. Findings: Advances in podocyte biology have identified many candidates for therapeutic targets and potential biomarkers of glomerular disease. The goal of precision medicine in GN is now being pursued with recent technological improvements in genetics, accessibility of biologic and clinical information with tissue biobanks, high-throughput analysis of large-scale data sets, and new human model systems such as kidney organoids. Conclusion: With advances in data collection, technologies, and experimental model systems, we now have vast tools available to pursue precision medicine in GN. We anticipate a growing number of studies integrating data from high-throughput analysis with the development of diagnostic tools and targeted therapies for GN in the near future.
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Affiliation(s)
- Yulu Cherry Liu
- Department of Cell Biology, Harvard Medical School, Boston, MA, USA
| | - Justin Chun
- Division of Nephrology, Department of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA.,Division of Nephrology, Department of Medicine, University of Calgary, Alberta, Canada
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44
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González-Mariscal L, Raya-Sandino A, González-González L, Hernández-Guzmán C. Relationship between G proteins coupled receptors and tight junctions. Tissue Barriers 2018; 6:e1414015. [PMID: 29420165 DOI: 10.1080/21688370.2017.1414015] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Tight junctions (TJs) are sites of cell-cell adhesion, constituted by a cytoplasmic plaque of molecules linked to integral proteins that form a network of strands around epithelial and endothelial cells at the uppermost portion of the lateral membrane. TJs maintain plasma membrane polarity and form channels and barriers that regulate the transit of ions and molecules through the paracellular pathway. This structure that regulates traffic between the external milieu and the organism is affected in numerous pathological conditions and constitutes an important target for therapeutic intervention. Here, we describe how a wide array of G protein-coupled receptors that are activated by diverse stimuli including light, ions, hormones, peptides, lipids, nucleotides and proteases, signal through heterotrimeric G proteins, arrestins and kinases to regulate TJs present in the blood-brain barrier, the blood-retinal barrier, renal tubular cells, keratinocytes, lung and colon, and the slit diaphragm of the glomerulus.
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Affiliation(s)
- Lorenza González-Mariscal
- a Department of Physiology , Biophysics and Neuroscience, Center for Research and Advanced Studies (Cinvestav) , Mexico City , Mexico
| | - Arturo Raya-Sandino
- a Department of Physiology , Biophysics and Neuroscience, Center for Research and Advanced Studies (Cinvestav) , Mexico City , Mexico
| | - Laura González-González
- a Department of Physiology , Biophysics and Neuroscience, Center for Research and Advanced Studies (Cinvestav) , Mexico City , Mexico
| | - Christian Hernández-Guzmán
- a Department of Physiology , Biophysics and Neuroscience, Center for Research and Advanced Studies (Cinvestav) , Mexico City , Mexico
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45
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Cell shape information is transduced through tension-independent mechanisms. Nat Commun 2017; 8:2145. [PMID: 29247198 PMCID: PMC5732205 DOI: 10.1038/s41467-017-02218-4] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2017] [Accepted: 11/14/2017] [Indexed: 01/25/2023] Open
Abstract
The shape of a cell within tissues can represent the history of chemical and physical signals that it encounters, but can information from cell shape regulate cellular phenotype independently? Using optimal control theory to constrain reaction-diffusion schemes that are dependent on different surface-to-volume relationships, we find that information from cell shape can be resolved from mechanical signals. We used microfabricated 3-D biomimetic chips to validate predictions that shape-sensing occurs in a tension-independent manner through integrin β3 signaling pathway in human kidney podocytes and smooth muscle cells. Differential proteomics and functional ablation assays indicate that integrin β3 is critical in transduction of shape signals through ezrin–radixin–moesin (ERM) family. We used experimentally determined diffusion coefficients and experimentally validated simulations to show that shape sensing is an emergent cellular property enabled by multiple molecular characteristics of integrin β3. We conclude that 3-D cell shape information, transduced through tension-independent mechanisms, can regulate phenotype. It is not known whether the shape of a cell can regulate cellular phenotype independently. Here, the authors show that culturing kidney podocytes or smooth muscle cells on 3-D biomimetic surfaces results in phenotypic changes and that cell shape is sensed by integrin β3 in a tension-independent manner.
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Hochapfel F, Denk L, Mendl G, Schulze U, Maaßen C, Zaytseva Y, Pavenstädt H, Weide T, Rachel R, Witzgall R, Krahn MP. Distinct functions of Crumbs regulating slit diaphragms and endocytosis in Drosophila nephrocytes. Cell Mol Life Sci 2017; 74:4573-4586. [PMID: 28717874 PMCID: PMC11107785 DOI: 10.1007/s00018-017-2593-y] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2016] [Revised: 06/26/2017] [Accepted: 07/13/2017] [Indexed: 10/19/2022]
Abstract
Mammalian podocytes, the key determinants of the kidney's filtration barrier, differentiate from columnar epithelial cells and several key determinants of apical-basal polarity in the conventional epithelia have been shown to regulate podocyte morphogenesis and function. However, little is known about the role of Crumbs, a conserved polarity regulator in many epithelia, for slit-diaphragm formation and podocyte function. In this study, we used Drosophila nephrocytes as model system for mammalian podocytes and identified a conserved function of Crumbs proteins for cellular morphogenesis, nephrocyte diaphragm assembly/maintenance, and endocytosis. Nephrocyte-specific knock-down of Crumbs results in disturbed nephrocyte diaphragm assembly/maintenance and decreased endocytosis, which can be rescued by Drosophila Crumbs as well as human Crumbs2 and Crumbs3, which were both expressed in human podocytes. In contrast to the extracellular domain, which facilitates nephrocyte diaphragm assembly/maintenance, the intracellular FERM-interaction motif of Crumbs is essential for regulating endocytosis. Moreover, Moesin, which binds to the FERM-binding domain of Crumbs, is essential for efficient endocytosis. Thus, we describe here a new mechanism of nephrocyte development and function, which is likely to be conserved in mammalian podocytes.
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Affiliation(s)
- Florian Hochapfel
- Molecular and Cellular Anatomy, University of Regensburg, Universitätsstr. 31, 93053, Regensburg, Germany
- Medizinische Klinik und Poliklinik D, Universitätsklinikum Münster, Domagkstr. 3a, 48149, Münster, Germany
| | - Lucia Denk
- Molecular and Cellular Anatomy, University of Regensburg, Universitätsstr. 31, 93053, Regensburg, Germany
| | - Gudrun Mendl
- Molecular and Cellular Anatomy, University of Regensburg, Universitätsstr. 31, 93053, Regensburg, Germany
| | - Ulf Schulze
- Medizinische Klinik und Poliklinik D, Universitätsklinikum Münster, Domagkstr. 3a, 48149, Münster, Germany
| | - Christine Maaßen
- Molecular and Cellular Anatomy, University of Regensburg, Universitätsstr. 31, 93053, Regensburg, Germany
| | - Yulia Zaytseva
- Molecular and Cellular Anatomy, University of Regensburg, Universitätsstr. 31, 93053, Regensburg, Germany
| | - Hermann Pavenstädt
- Medizinische Klinik und Poliklinik D, Universitätsklinikum Münster, Domagkstr. 3a, 48149, Münster, Germany
| | - Thomas Weide
- Medizinische Klinik und Poliklinik D, Universitätsklinikum Münster, Domagkstr. 3a, 48149, Münster, Germany
| | - Reinhard Rachel
- Molecular and Cellular Anatomy, University of Regensburg, Universitätsstr. 31, 93053, Regensburg, Germany
| | - Ralph Witzgall
- Molecular and Cellular Anatomy, University of Regensburg, Universitätsstr. 31, 93053, Regensburg, Germany
| | - Michael P Krahn
- Molecular and Cellular Anatomy, University of Regensburg, Universitätsstr. 31, 93053, Regensburg, Germany.
- Medizinische Klinik und Poliklinik D, Universitätsklinikum Münster, Domagkstr. 3a, 48149, Münster, Germany.
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Lu Y, Ye Y, Bao W, Yang Q, Wang J, Liu Z, Shi S. Genome-wide identification of genes essential for podocyte cytoskeletons based on single-cell RNA sequencing. Kidney Int 2017; 92:1119-1129. [PMID: 28709640 DOI: 10.1016/j.kint.2017.04.022] [Citation(s) in RCA: 49] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2017] [Revised: 04/06/2017] [Accepted: 04/13/2017] [Indexed: 12/21/2022]
Abstract
Gene expression differs substantially among individual cells of the same type. We speculate that genes that are expressed in all but a portion of cells of a given cell type would be likely essential and required for either the cell survival (housekeeping) or for the cell type's unique structure and function, enabling the organism to survive. Here, we performed RNA-seq of 20 mouse podocytes using the Fluidigm C1 system and identified 335 genes that were expressed in all of them. Among them, 239 genes were also expressed in mesangial and endothelial cells and were involved in energy metabolism, protein synthesis, etc., as housekeeping genes. In contrast, 92 genes were preferentially expressed in podocytes (over five-fold versus expression in mesangial and endothelial cells) and are, therefore, the essential candidate genes specific for podocytes. Assessments by bioinformatics, conserved expression in human podocytes, and association with injury/disease all support the essentiality of these genes for podocytes. Factually, 27 of the 92 genes are already known to be essential for podocyte structure and function. Thirty-seven novel genes were functionally analyzed by siRNA silencing, and we found that a deficiency of 30 genes led to either cytoskeletal injury (FGFR1, AOX1, AIF1L, HAUS8, RAB3B, LPIN2, GOLIM4, CERS6, ARHGEF18, ARPC1A, SRGAP1, ITGB5, ILDR2, MPP5, TSC22D1, DNAJC11, SEPT10, MOCS2, FNBP1L, and TMOD3) or significant downregulation of CD2AP and synaptopodin (IFT80, MYOM2, ANXA4, CYB5R4, GPC1, ZNF277, NSF, ITGAV, CRYAB, and MTSS1). Thus, the list of genes essential for podocyte cytoskeletons is expanded by single-cell RNA sequencing. It appears that podocyte-specific essential genes are mainly associated with podocyte cytoskeletons.
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Affiliation(s)
- Yuqiu Lu
- National Clinical Research Center for Kidney Diseases, Jinling Hospital, Nanjing University School of Medicine, Nanjing, Jiangsu 210002, China
| | - Yuting Ye
- National Clinical Research Center for Kidney Diseases, Jinling Hospital, Nanjing University School of Medicine, Nanjing, Jiangsu 210002, China
| | - Wenduona Bao
- National Clinical Research Center for Kidney Diseases, Jinling Hospital, Nanjing University School of Medicine, Nanjing, Jiangsu 210002, China
| | - Qianqian Yang
- National Clinical Research Center for Kidney Diseases, Jinling Hospital, Nanjing University School of Medicine, Nanjing, Jiangsu 210002, China
| | - Jinquan Wang
- National Clinical Research Center for Kidney Diseases, Jinling Hospital, Nanjing University School of Medicine, Nanjing, Jiangsu 210002, China
| | - Zhihong Liu
- National Clinical Research Center for Kidney Diseases, Jinling Hospital, Nanjing University School of Medicine, Nanjing, Jiangsu 210002, China
| | - Shaolin Shi
- National Clinical Research Center for Kidney Diseases, Jinling Hospital, Nanjing University School of Medicine, Nanjing, Jiangsu 210002, China.
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Michgehl U, Pavenstädt H, Vollenbröker B. Cross talk between the Crumbs complex and Hippo signaling in renal epithelial cells. Pflugers Arch 2017; 469:917-926. [PMID: 28612137 DOI: 10.1007/s00424-017-2004-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2017] [Revised: 05/18/2017] [Accepted: 05/19/2017] [Indexed: 12/12/2022]
Abstract
Cell polarity has a crucial role in organizing cells into tissues and in mediating transport processes and cell-cell communication. Especially the cells of the nephron require apicobasal polarity to establish and maintain their barrier function. The Crumbs complex including the integral membrane protein Crumbs, as well as Pals1 and Patj, is essential for the establishment of apicobasal polarity. The interactions of the core proteins and the interplay with other processes have been characterized in various epithelial cell lines in detail. Notably, Crb2 and Crb3 are expressed within the kidney and play an important role in the proper function of podocytes and tubules, respectively. The interaction of polarity proteins and components of the Hippo pathway-an evolutionarily highly conserved kinase cascade regulating cell proliferation, organ size, and tissue regeneration-has been discovered recently. Here, we discuss potential molecular and physiological links between the Crumbs complex and the Hippo pathway in renal cells.
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Affiliation(s)
- U Michgehl
- Internal Medicine D, University Hospital of Muenster, Albert-Schweitzer-Campus 1, A14, D-48149, Muenster, Germany.
| | - H Pavenstädt
- Internal Medicine D, University Hospital of Muenster, Albert-Schweitzer-Campus 1, A14, D-48149, Muenster, Germany
| | - B Vollenbröker
- Internal Medicine D, University Hospital of Muenster, Albert-Schweitzer-Campus 1, A14, D-48149, Muenster, Germany
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Abstract
The last 5 years have witnessed tremendous advances in both light- and electron-microscopic techniques in the biomedical sciences. Application of these new cutting-edge methods to glomerular biology has advanced considerably and, in part, completed our endeavor to draw a detailed map of the glomerular tuft. The scope of this review is to illustrate these new insights within both the morphometry of podocyte cells and the architecture of the glomerular filtration barrier and to assess whether these findings have indeed had an impact on our biological understanding of glomerular function.
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Affiliation(s)
- Florian Grahammer
- Department of Medicine IV, Medical Center and Faculty of Medicine, University of Freiburg, Breisacherstrasse 66, 79106, Freiburg, Germany. .,III. Medical Clinic, University Medical Center Hamburg-Eppendorf, Martinistrasse 52, 20246, Hamburg, Germany.
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A biomimetic gelatin-based platform elicits a pro-differentiation effect on podocytes through mechanotransduction. Sci Rep 2017; 7:43934. [PMID: 28262745 PMCID: PMC5338254 DOI: 10.1038/srep43934] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2016] [Accepted: 02/01/2017] [Indexed: 01/12/2023] Open
Abstract
Using a gelatin microbial transglutaminase (gelatin-mTG) cell culture platform tuned to exhibit stiffness spanning that of healthy and diseased glomeruli, we demonstrate that kidney podocytes show marked stiffness sensitivity. Podocyte-specific markers that are critical in the formation of the renal filtration barrier are found to be regulated in association with stiffness-mediated cellular behaviors. While podocytes typically de-differentiate in culture and show diminished physiological function in nephropathies characterized by altered tissue stiffness, we show that gelatin-mTG substrates with Young’s modulus near that of healthy glomeruli elicit a pro-differentiation and maturation response in podocytes better than substrates either softer or stiffer. The pro-differentiation phenotype is characterized by upregulation of gene and protein expression associated with podocyte function, which is observed for podocytes cultured on gelatin-mTG gels of physiological stiffness independent of extracellular matrix coating type and density. Signaling pathways involved in stiffness-mediated podocyte behaviors are identified, revealing the interdependence of podocyte mechanotransduction and maintenance of their physiological function. This study also highlights the utility of the gelatin-mTG platform as an in vitro system with tunable stiffness over a range relevant for recapitulating mechanical properties of soft tissues, suggesting its potential impact on a wide range of research in cellular biophysics.
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