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Bhardwaj R, Bhardwaj A, Dhawan DK, Tandon C, Kaur T. 4-PBA rescues hyperoxaluria induced nephrolithiasis by modulating urinary glycoproteins: Cross talk between endoplasmic reticulum, calcium homeostasis and mitochondria. Life Sci 2022; 305:120786. [PMID: 35809664 DOI: 10.1016/j.lfs.2022.120786] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2022] [Revised: 06/28/2022] [Accepted: 07/01/2022] [Indexed: 12/15/2022]
Abstract
AIM Urinary glycoproteins such as Tamm Horsfall Protein (THP) and Osteopontin (OPN) are well established key regulators of renal stone formation. Additionally, recent revelations have highlighted the influence of Endoplasmic Reticulum (ER) and mitochondria of crucial importance in nephrolithiasis. However, till date conclusive approach highlighting the influence of ER stress on urinary glycoproteins and chaperone in nephrolithiasis remains elusive. Therefore, the present study was focussed on deciphering the possible effect of 4-PBA mitigating ER stress on urinary glycoproteins and calnexin (chaperone) with emphasis on interlinking calcium homeostasis in hyperoxaluric rats. MATERIAL AND METHODS Post 9 days of treatment, animals were sacrificed, and renal tissues were investigated for urinary glycoproteins, calnexin, calcium homeostasis, ER environment, redox status, and mitochondrial linkage. KEY FINDINGS 4-PBA appreciably reversed the altered levels of THP, OPN, and calnexin observed along with curtailing the disrupted calcium homeostasis when assessed for SERCA activity and intra-cellular calcium levels. Additionally, significant improvement in the perturbed ER environment as verified by escalated ER stress markers, disturbed protein folding-aggregation-degradation (congo red assay) pathway, and redox status was found post 4-PBA intervention. Interestingly, linkage of ER stress and mitochondria was established under hyperoxaluric conditions when assessed for protein levels of VDAC1 and GRP75. SIGNIFICANCE 4-PBA treatment resulted in rectifying the repercussions of ER-mitochondrial caused distress when assessed for protein folding/aggregation/degradation events along with disturbed calcium homeostasis. The present study advocates the necessity to adopt a holistic vision towards hyperoxaluria with emphasis on glycoproteins and ER environment.
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Affiliation(s)
- Rishi Bhardwaj
- Department of Biophysics, Panjab University, Chandigarh, India
| | - Ankita Bhardwaj
- Department of Biophysics, Panjab University, Chandigarh, India
| | | | | | - Tanzeer Kaur
- Department of Biophysics, Panjab University, Chandigarh, India.
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Utami SB, Endo R, Hamada T, Notsu T, Minato H, Komatsu K, Nakayama Y, Shirayoshi Y, Yamamoto K, Okada S, Ninomiya H, Otuki A, Hisatome I. Hsp70 promotes maturation of uromodulin mutants that cause familial juvenile hyperuricemic nephropathy and suppresses cellular damage. Clin Exp Nephrol 2022; 26:522-529. [PMID: 35212881 DOI: 10.1007/s10157-022-02196-y] [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: 12/27/2021] [Accepted: 02/04/2022] [Indexed: 11/28/2022]
Abstract
BACKGROUND Familial juvenile hyperuricemic nephropathy (FJHN) is an autosomal dominant disorder caused by mutations in UMOD. Here we studied effects of genetic expression and pharmacological induction of Hsp70 on the UMOD mutants C112Y and C217G. METHODS We expressed wild type (WT), C112Y and C217G in HEK293 cells and studied their maturation and cellular damage using western blot and flow cytometry. RESULTS Expression of C112Y or C217G increased pro-apoptotic proteins, decreased anti-apoptotic proteins, and induced cellular apoptosis as examined by annexin V staining and flow cytometry. Overexpression of Hsp70 or administration of an Hsp70 inducer geranylgeranylacetone (GGA) promoted maturation of the mutant proteins, increased their secreted forms, normalized the levels of pro- and anti-apoptotic proteins and suppressed apoptosis. CONCLUSION These findings indicated that Hsp70 enhanced maturation of C112Y and C217G and reduced cellular apoptosis, suggesting that Hsp70 induction might be of a therapeutic value for treatment of FJHN.
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Affiliation(s)
- Sulistiyati Bayu Utami
- Department of Genetic Medicine and Regenerative Therapeutics, Faculty of Medicine, Tottori University, Yonago, Japan.,Department of Cardiology and Vascular Medicine, Diponegoro University, Semarang, Indonesia
| | - Ryo Endo
- Department of Anesthesiology, Faculty of Medicine, Tottori University, Yonago, Japan
| | - Toshihiro Hamada
- Department of Community-Based Family Medicine, Faculty of Medicine, Tottori University, Yonago, Japan.
| | - Tomomi Notsu
- Department of Genetic Medicine and Regenerative Therapeutics, Faculty of Medicine, Tottori University, Yonago, Japan
| | - Hiroyuki Minato
- Department of Anesthesiology, Faculty of Medicine, Tottori University, Yonago, Japan
| | - Koji Komatsu
- Department of Psychiatry, Faculty of Medicine, Tottori University, Yonago, Japan
| | - Yuji Nakayama
- Research Center for Bioscience and Technology, Tottori University, Yonago, Japan
| | - Yasuaki Shirayoshi
- Department of Genetic Medicine and Regenerative Therapeutics, Faculty of Medicine, Tottori University, Yonago, Japan
| | - Kazuhiro Yamamoto
- Division of Cardiovascular Medicine, Department of Molecular Medicine and Therapeutics, Faculty of Medicine, Tottori University, Yonago, 683-8503, Japan
| | - Shinichi Okada
- Department of Pediatrics, Yonago Medical Center, Yonago, Japan
| | - Haruaki Ninomiya
- Department of Biological Regulation, Faculty of Medicine, Tottori University, Yonago, Japan
| | - Akihiro Otuki
- Department of Anesthesiology, Faculty of Medicine, Tottori University, Yonago, Japan
| | - Ichiro Hisatome
- Department of Genetic Medicine and Regenerative Therapeutics, Faculty of Medicine, Tottori University, Yonago, Japan.,Department of Cardiovascular Medicine, Yonago Medical Center, Yonago, Japan
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Mary S, Boder P, Rossitto G, Graham L, Scott K, Flynn A, Kipgen D, Graham D, Delles C. Salt loading decreases urinary excretion and increases intracellular accumulation of uromodulin in stroke-prone spontaneously hypertensive rats. Clin Sci (Lond) 2021; 135:2749-2761. [PMID: 34870708 PMCID: PMC8689196 DOI: 10.1042/cs20211017] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2021] [Revised: 11/24/2021] [Accepted: 12/06/2021] [Indexed: 12/15/2022]
Abstract
Uromodulin (UMOD) is the most abundant renal protein secreted into urine by the thick ascending limb (TAL) epithelial cells of the loop of Henle. Genetic studies have demonstrated an association between UMOD risk variants and hypertension. We aimed to dissect the role of dietary salt in renal UMOD excretion in normotension and chronic hypertension. Normotensive Wistar-Kyoto rats (WKY) and stroke-prone spontaneously hypertensive rats (SHRSP) (n=8/sex/strain) were maintained on 1% NaCl for 3 weeks. A subset of salt-loaded SHRSP was treated with nifedipine. Salt-loading in SHRSP increased blood pressure (ΔSBP 35 ± 5 mmHg, P<0.0001) and kidney injury markers such as kidney injury marker-1 (KIM-1; fold change, FC 3.4; P=0.003), neutrophil gelatinase-associated lipocalin (NGAL; FC, 2.0; P=0.012) and proteinuria. After salt-loading there was a reduction in urinary UMOD excretion in WKY and SHRSP by 26 and 55% respectively, compared with baseline. Nifedipine treatment reduced blood pressure (BP) in SHRSP, however, did not prevent salt-induced reduction in urinary UMOD excretion. In all experiments, changes in urinary UMOD excretion were dissociated from kidney UMOD protein and mRNA levels. Colocalization and ex-vivo studies showed that salt-loading increased intracellular UMOD retention in both WKY and SHRSP. Our study provides novel insights into the interplay among salt, UMOD, and BP. The role of UMOD as a cardiovascular risk marker deserves mechanistic reappraisal and further investigations based on our findings.
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Affiliation(s)
- Sheon Mary
- Institute of Cardiovascular and Medical Sciences, University of Glasgow, Glasgow, Scotland, U.K
| | - Philipp Boder
- Institute of Cardiovascular and Medical Sciences, University of Glasgow, Glasgow, Scotland, U.K
| | - Giacomo Rossitto
- Institute of Cardiovascular and Medical Sciences, University of Glasgow, Glasgow, Scotland, U.K
- Department of Medicine, University of Padua, Padua, Italy
| | - Lesley Graham
- Institute of Cardiovascular and Medical Sciences, University of Glasgow, Glasgow, Scotland, U.K
| | - Kayley Scott
- Institute of Cardiovascular and Medical Sciences, University of Glasgow, Glasgow, Scotland, U.K
| | - Arun Flynn
- Institute of Cardiovascular and Medical Sciences, University of Glasgow, Glasgow, Scotland, U.K
| | - David Kipgen
- Department of Pathology, Queen Elizabeth University Hospital, Glasgow, Scotland, U.K
| | - Delyth Graham
- Institute of Cardiovascular and Medical Sciences, University of Glasgow, Glasgow, Scotland, U.K
| | - Christian Delles
- Institute of Cardiovascular and Medical Sciences, University of Glasgow, Glasgow, Scotland, U.K
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Abstract
Autosomal dominant tubulointerstitial kidney disease (ADTKD) is a recently defined entity that includes rare kidney diseases characterized by tubular damage and interstitial fibrosis in the absence of glomerular lesions, with inescapable progression to end-stage renal disease. These diseases have long been neglected and under-recognized, in part due to confusing and inconsistent terminology. The introduction of a gene-based, unifying terminology led to the identification of an increasing number of cases, with recent data suggesting that ADTKD is one of the more common monogenic kidney diseases after autosomal dominant polycystic kidney disease, accounting for ~5% of monogenic disorders causing chronic kidney disease. ADTKD is caused by mutations in at least five different genes, including UMOD, MUC1, REN, HNF1B and, more rarely, SEC61A1. These genes encode various proteins with renal and extra-renal functions. The mundane clinical characteristics and lack of appreciation of family history often result in a failure to diagnose ADTKD. This Primer highlights the different types of ADTKD and discusses the distinct genetic and clinical features as well as the underlying mechanisms.
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Graham LA, Aman A, Campbell DD, Augley J, Graham D, McBride MW, Fraser NJ, Ferreri NR, Dominiczak AF, Padmanabhan S. Salt stress in the renal tubules is linked to TAL-specific expression of uromodulin and an upregulation of heat shock genes. Physiol Genomics 2018; 50:964-972. [PMID: 30216136 PMCID: PMC6293113 DOI: 10.1152/physiolgenomics.00057.2018] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2018] [Revised: 08/20/2018] [Accepted: 09/12/2018] [Indexed: 12/15/2022] Open
Abstract
Previously, our comprehensive cardiovascular characterization study validated Uromodulin as a blood pressure gene. Uromodulin is a glycoprotein exclusively synthesized at the thick ascending limb of the loop of Henle and is encoded by the Umod gene. Umod-/- mice have significantly lower blood pressure than Umod+/+ mice, are resistant to salt-induced changes in blood pressure, and show a leftward shift in pressure-natriuresis curves reflecting changes of sodium reabsorption. Salt stress triggers transcription factors and genes that alter renal sodium reabsorption. To date there are no studies on renal transcriptome responses to salt stress. Here we aimed use RNA-Seq to delineate salt stress pathways in tubules isolated from Umod+/+ mice (a model of sodium retention) and Umod-/- mice (a model of sodium depletion) ± 300 mosmol sodium chloride ( n = 3 per group). In response to salt stress, the tubules of Umod+/+ mice displayed an upregulation of heat shock transcripts. The greatest changes occurred in the expression of: Hspa1a (Log2 fold change 4.35, P = 2.48 e-12) and Hspa1b (Log2 fold change 4.05, P = 2.48 e-12). This response was absent in tubules of Umod-/- mice. Interestingly, seven of the genes discordantly expressed in the Umod-/- tubules were electrolyte transporters. Our results are the first to show that salt stress in renal tubules alters the transcriptome, increasing the expression of heat shock genes. This direction of effect in Umod+/+ tubules suggest the difference is due to the presence of Umod facilitating greater sodium entry into the tubule cell reflecting a specific response to salt stress.
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Affiliation(s)
- Lesley A Graham
- The British Heart Foundation Centre of Excellence, Institute of Cardiovascular and Medical Sciences, College of Medical, Veterinary, and Life Sciences, University of Glasgow , Glasgow , United Kingdom
| | - Alisha Aman
- The British Heart Foundation Centre of Excellence, Institute of Cardiovascular and Medical Sciences, College of Medical, Veterinary, and Life Sciences, University of Glasgow , Glasgow , United Kingdom
| | - Desmond D Campbell
- The British Heart Foundation Centre of Excellence, Institute of Cardiovascular and Medical Sciences, College of Medical, Veterinary, and Life Sciences, University of Glasgow , Glasgow , United Kingdom
| | - Julian Augley
- Wolfson Wohl Cancer Research Centre, Glasgow Polyomics, University of Glasgow, Bearsden, United Kingdom
| | - Delyth Graham
- The British Heart Foundation Centre of Excellence, Institute of Cardiovascular and Medical Sciences, College of Medical, Veterinary, and Life Sciences, University of Glasgow , Glasgow , United Kingdom
| | - Martin W McBride
- The British Heart Foundation Centre of Excellence, Institute of Cardiovascular and Medical Sciences, College of Medical, Veterinary, and Life Sciences, University of Glasgow , Glasgow , United Kingdom
| | - Niall J Fraser
- University of Dundee, Ninewells Hospital , Dundee , United Kingdom
| | - Nicholas R Ferreri
- Department of Pharmacology, New York Medical College, Valhalla, New York
| | - Anna F Dominiczak
- The British Heart Foundation Centre of Excellence, Institute of Cardiovascular and Medical Sciences, College of Medical, Veterinary, and Life Sciences, University of Glasgow , Glasgow , United Kingdom
| | - Sandosh Padmanabhan
- The British Heart Foundation Centre of Excellence, Institute of Cardiovascular and Medical Sciences, College of Medical, Veterinary, and Life Sciences, University of Glasgow , Glasgow , United Kingdom
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Ma L, Liu Y, Landry NK, El-Achkar TM, Lieske JC, Wu XR. Point mutation in D8C domain of Tamm-Horsfall protein/uromodulin in transgenic mice causes progressive renal damage and hyperuricemia. PLoS One 2017; 12:e0186769. [PMID: 29145399 PMCID: PMC5690637 DOI: 10.1371/journal.pone.0186769] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2017] [Accepted: 10/07/2017] [Indexed: 12/28/2022] Open
Abstract
Hereditary mutations in Tamm-Horsfall protein (THP/uromodulin) gene cause autosomal dominant kidney diseases characterized by juvenile-onset hyperuricemia, gout and progressive kidney failure, although the disease pathogenesis remains unclear. Here we show that targeted expression in transgenic mice of a mutation within the domain of 8 cysteines of THP in kidneys' thick ascending limb (TAL) caused unfolded protein response in younger (1-month old) mice and apoptosis in older (12-month old) mice. While the young mice had urine concentration defects and polyuria, such defects progressively reversed in the older mice to marked oliguria, highly concentrated urine, fibrotic kidneys and reduced creatinine clearance. Both the young and the old transgenic mice had significantly higher serum uric acid and its catabolic product, allantoin, than age-matched wild-type mice. This THP mutation apparently caused primary defects in TAL by compromising the luminal translocation and reabsorptive functions of NKCC2 and ROMK and secondary responses in proximal tubules by upregulating NHE3 and URAT1. Our results strongly suggest that the progressive worsening of kidney functions reflects the accumulation of the deleterious effects of the misfolded mutant THP and the compensatory responses. Transgenic mice recapitulating human THP/uromodulin-associated kidney diseases could be used to elucidate their pathogenesis and test novel therapeutic strategies.
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Affiliation(s)
- Lijie Ma
- Departments of Urology and Pathology, New York University School of Medicine, New York, New York, United States of America
| | - Yan Liu
- Departments of Urology and Pathology, New York University School of Medicine, New York, New York, United States of America
| | - Nichole K. Landry
- Division of Nephrology, Indiana University School of Medicine and Indianapolis VA, Indianapolis, Indiana, United States of America
| | - Tarek M. El-Achkar
- Division of Nephrology, Indiana University School of Medicine and Indianapolis VA, Indianapolis, Indiana, United States of America
| | - John C. Lieske
- Division of Nephrology and Hypertension, Mayo Clinic, Rochester, Minnesota, United States of America
| | - Xue-Ru Wu
- Departments of Urology and Pathology, New York University School of Medicine, New York, New York, United States of America
- Veterans Affairs New York Harbor Healthcare System, Manhattan Campus, New York, New York, United States of America
- * E-mail:
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7
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Graham LA, Dominiczak AF, Ferreri NR. Role of renal transporters and novel regulatory interactions in the TAL that control blood pressure. Physiol Genomics 2017; 49:261-276. [PMID: 28389525 PMCID: PMC5451551 DOI: 10.1152/physiolgenomics.00017.2017] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2017] [Revised: 03/27/2017] [Accepted: 04/05/2017] [Indexed: 12/31/2022] Open
Abstract
Hypertension (HTN), a major public health issue is currently the leading factor in the global burden of disease, where associated complications account for 9.4 million deaths worldwide every year. Excessive dietary salt intake is among the environmental factors that contribute to HTN, known as salt sensitivity. The heterogeneity of salt sensitivity and the multiple mechanisms that link high salt intake to increases in blood pressure are of upmost importance for therapeutic application. A continual increase in the kidney's reabsorption of sodium (Na+) relies on sequential actions at various segments along the nephron. When the distal segments of the nephron fail to regulate Na+, the effects on Na+ homeostasis are unfavorable. We propose that the specific nephron region where increased active uptake occurs as a result of variations in Na+ reabsorption is at the thick ascending limb of the loop of Henle (TAL). The purpose of this review is to urge the consideration of the TAL as contributing to the pathophysiology of salt-sensitive HTN. Further research in this area will enable development of a therapeutic application for targeted treatment.
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Affiliation(s)
- Lesley A Graham
- BHF Glasgow Cardiovascular Research Centre, University of Glasgow Cardiovascular and Medical Sciences, Glasgow, United Kingdom; and
| | - Anna F Dominiczak
- BHF Glasgow Cardiovascular Research Centre, University of Glasgow Cardiovascular and Medical Sciences, Glasgow, United Kingdom; and
| | - Nicholas R Ferreri
- Department of Pharmacology, New York Medical College, Valhalla, New York
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BMP type II receptor as a therapeutic target in pulmonary arterial hypertension. Cell Mol Life Sci 2017; 74:2979-2995. [PMID: 28447104 PMCID: PMC5501910 DOI: 10.1007/s00018-017-2510-4] [Citation(s) in RCA: 74] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2016] [Revised: 03/09/2017] [Accepted: 03/17/2017] [Indexed: 12/30/2022]
Abstract
Pulmonary arterial hypertension (PAH) is a chronic disease characterized by a progressive elevation in mean pulmonary arterial pressure. This occurs due to abnormal remodeling of small peripheral lung vasculature resulting in progressive occlusion of the artery lumen that eventually causes right heart failure and death. The most common cause of PAH is inactivating mutations in the gene encoding a bone morphogenetic protein type II receptor (BMPRII). Current therapeutic options for PAH are limited and focused mainly on reversal of pulmonary vasoconstriction and proliferation of vascular cells. Although these treatments can relieve disease symptoms, PAH remains a progressive lethal disease. Emerging data suggest that restoration of BMPRII signaling in PAH is a promising alternative that could prevent and reverse pulmonary vascular remodeling. Here we will focus on recent advances in rescuing BMPRII expression, function or signaling to prevent and reverse pulmonary vascular remodeling in PAH and its feasibility for clinical translation. Furthermore, we summarize the role of described miRNAs that directly target the BMPR2 gene in blood vessels. We discuss the therapeutic potential and the limitations of promising new approaches to restore BMPRII signaling in PAH patients. Different mutations in BMPR2 and environmental/genetic factors make PAH a heterogeneous disease and it is thus likely that the best approach will be patient-tailored therapies.
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9
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Schaeffer C, Merella S, Pasqualetto E, Lazarevic D, Rampoldi L. Mutant uromodulin expression leads to altered homeostasis of the endoplasmic reticulum and activates the unfolded protein response. PLoS One 2017; 12:e0175970. [PMID: 28437467 PMCID: PMC5402980 DOI: 10.1371/journal.pone.0175970] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2017] [Accepted: 04/03/2017] [Indexed: 12/19/2022] Open
Abstract
Uromodulin is the most abundant urinary protein in physiological conditions. It is exclusively produced by renal epithelial cells lining the thick ascending limb of Henle's loop (TAL) and it plays key roles in kidney function and disease. Mutations in UMOD, the gene encoding uromodulin, cause autosomal dominant tubulointerstitial kidney disease uromodulin-related (ADTKD-UMOD), characterised by hyperuricemia, gout and progressive loss of renal function. While the primary effect of UMOD mutations, retention in the endoplasmic reticulum (ER), is well established, its downstream effects are still largely unknown. To gain insight into ADTKD-UMOD pathogenesis, we performed transcriptional profiling and biochemical characterisation of cellular models (immortalised mouse TAL cells) of robust expression of wild type or mutant GFP-tagged uromodulin. In this model mutant uromodulin accumulation in the ER does not impact on cell viability and proliferation. Transcriptional profiling identified 109 genes that are differentially expressed in mutant cells relative to wild type ones. Up-regulated genes include several ER resident chaperones and protein disulphide isomerases. Consistently, pathway enrichment analysis indicates that mutant uromodulin expression affects ER function and protein homeostasis. Interestingly, mutant uromodulin expression induces the Unfolded Protein Response (UPR), and specifically the IRE1 branch, as shown by an increased splicing of XBP1. Consistent with UPR induction, we show increased interaction of mutant uromodulin with ER chaperones Bip, calnexin and PDI. Using metabolic labelling, we also demonstrate that while autophagy plays no role, mutant protein is partially degraded by the proteasome through ER-associated degradation. Our work demonstrates that ER stress could play a central role in ADTKD-UMOD pathogenesis. This sets the bases for future work to develop novel therapeutic strategies through modulation of ER homeostasis and associated protein degradation pathways.
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Affiliation(s)
- Céline Schaeffer
- Molecular Genetics of Renal Disorders, Division of Genetics and Cell Biology, IRCCS San Raffaele Scientific Institute, Milan, Italy
| | - Stefania Merella
- Center of Translational Genomics and Bioinformatics, IRCCS San Raffaele Scientific Institute, Milan, Italy
| | - Elena Pasqualetto
- Molecular Genetics of Renal Disorders, Division of Genetics and Cell Biology, IRCCS San Raffaele Scientific Institute, Milan, Italy
| | - Dejan Lazarevic
- Center of Translational Genomics and Bioinformatics, IRCCS San Raffaele Scientific Institute, Milan, Italy
| | - Luca Rampoldi
- Molecular Genetics of Renal Disorders, Division of Genetics and Cell Biology, IRCCS San Raffaele Scientific Institute, Milan, Italy
- * E-mail:
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Sreedharan R, Van Why SK. Heat shock proteins in the kidney. Pediatr Nephrol 2016; 31:1561-70. [PMID: 26913726 DOI: 10.1007/s00467-015-3297-x] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/19/2015] [Revised: 12/01/2015] [Accepted: 12/07/2015] [Indexed: 12/15/2022]
Abstract
Heat shock proteins (Hsps) are essential to cell survival through their function as protein chaperones. The role they play in kidney health and disease is varied. Hsp induction may be either beneficial or detrimental to the kidney, depending on the specific Hsp, type of cell, and context. This review addresses the role of Hsps in the kidney, including during development, as osmoprotectants, and in various kidney disease models. Heat shock transcription factor, activated by a stress on renal cells, induces Hsp elaboration and separately regulates immune responses that can contribute to renal injury. Induced Hsps in the intracellular compartment are mostly beneficial in the kidney by stabilizing and restoring cell architecture and function through acting as protein chaperones. Intracellular Hsps also inhibit apoptosis and facilitate cell proliferation, preserving renal tubule viability after acute injury, but enhancing progression of cystic kidney disease and malignancy. Induced Hsps in the extracellular compartment, either circulating or located on outer cell membranes, are mainly detrimental through enhancing inflammation pathways to injury. Correctly harnessing these stress proteins promises the opportunity to alter the course of acute and chronic kidney disease.
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Affiliation(s)
- Rajasree Sreedharan
- Pediatrics, Nephrology, Medical College of Wisconsin, 999 N. 92nd St., Suite C510, Milwaukee, WI, 53226, USA
| | - Scott K Van Why
- Pediatrics, Nephrology, Medical College of Wisconsin, 999 N. 92nd St., Suite C510, Milwaukee, WI, 53226, USA.
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12
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Prejbisz A, Sellin L, Szwench-Pietrasz E, Woznowski M, Michałowska I, Blondin D, Sajnaga D, Epplen JT, Litwin M, Dekomien G, Januszewicz M, Helmchen U, Matuszkiewicz-Rowińska J, Adamczak M, Więcek A, Januszewicz A, Rump LC. Smaller caliber renal arteries are a novel feature of uromodulin-associated kidney disease. Kidney Int 2015; 88:160-6. [PMID: 25671765 DOI: 10.1038/ki.2015.2] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2014] [Revised: 11/26/2014] [Accepted: 12/11/2014] [Indexed: 12/15/2022]
Abstract
Hyperuricemia is very common in industrialized countries and known to promote vascular smooth muscle cell proliferation. Juvenile hyperuricemia is a hallmark of uromodulin-associated kidney disease characterized by progressive interstitial renal fibrosis leading to end-stage renal disease within decades. Here we describe a member of a Polish-German family with a history of familial background of chronic kidney disease, hyperuricemia, and gout. This patient had hypertension because of bilateral small renal arteries, hyperuricemia, and chronic kidney disease. Clinical and molecular studies were subsequently performed in 39 family members, which included a physical examination, Duplex ultrasound of the kidneys, laboratory tests for renal function, and urine analysis. In eight family members contrast-enhanced renal artery imaging by computed tomography-angiography or magnetic resonance imaging was conducted and showed that bilateral non-arteriosclerotic small caliber renal arteries were associated with hyperuricemia and chronic kidney disease. Of the 26 family members who underwent genotyping, 11 possessed the P236R mutation (c.707C>G) of the uromodulin gene. All family members with a small caliber renal artery carried the uromodulin P236R mutation. Statistical analysis showed a strong correlation between reduced renal artery lumen and decreased estimated glomerular filtration rate. Thus, bilateral small caliber renal arteries are a new clinical phenotype associated with an uromodulin mutation.
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Affiliation(s)
| | - Lorenz Sellin
- Department of Nephrology, Medical School, Heinrich Heine University, University Hospital Duesseldorf, Duesseldorf, Germany
| | | | - Magdalena Woznowski
- Department of Nephrology, Medical School, Heinrich Heine University, University Hospital Duesseldorf, Duesseldorf, Germany
| | | | - Dirk Blondin
- Department of Radiology, Medical School, Heinrich Heine University, Duesseldorf, Germany
| | - Dariusz Sajnaga
- Department of Cardiology, Railway Hospital, Pruszków, Poland
| | - Jorg T Epplen
- Department of Human Genetics, Ruhr University Bochum, Bochum, Germany
| | - Mieczysław Litwin
- Department of Nephrology and Arterial Hypertension, Department of Research, Children's Memorial Health Institute, Warsaw, Poland
| | - Gabriele Dekomien
- Department of Human Genetics, Ruhr University Bochum, Bochum, Germany
| | | | - Udo Helmchen
- Nierenregister Hamburg, Department of Pathology, University Hospital Eppendorf, Hamburg, Germany
| | | | - Marcin Adamczak
- Department of Nephrology, Endocrinology and Metabolic Diseases, Medical University of Silesia, Katowice, Poland
| | - Andrzej Więcek
- Department of Nephrology, Endocrinology and Metabolic Diseases, Medical University of Silesia, Katowice, Poland
| | | | - Lars C Rump
- Department of Nephrology, Medical School, Heinrich Heine University, University Hospital Duesseldorf, Duesseldorf, Germany
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13
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The therapeutic effects of 4-phenylbutyric acid in maintaining proteostasis. Int J Biochem Cell Biol 2015; 61:45-52. [PMID: 25660369 DOI: 10.1016/j.biocel.2015.01.015] [Citation(s) in RCA: 184] [Impact Index Per Article: 20.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2014] [Revised: 01/27/2015] [Accepted: 01/28/2015] [Indexed: 12/11/2022]
Abstract
Recently, there has been an increasing amount of literature published on the effects of 4-phenylbutyric acid (4-PBA) in various biological systems. 4-PBA is currently used clinically to treat urea cycle disorders under the trade name Buphenyl. Recent studies however have explored 4-PBA in the context of a low weight molecular weight chemical chaperone. Its properties as a chemical chaperone prevent misfolded protein aggregation and alleviate endoplasmic reticulum (ER) stress. As the ER is responsible for folding proteins targeted for use in membranes or secreted out of the cell, failure of maintaining adequate ER homeostasis may lead to protein misfolding and subsequent cell and organ pathology. Accumulation of misfolded proteins within the ER activates the unfolded protein response (UPR), a molecular repair response. The activation of the UPR aims to restore ER and cellular proteostasis by regulating the rate of synthesis of newly formed proteins as well as initiating molecular programs aimed to help fold or degrade misfolded proteins. If proteostasis is not restored, the UPR may initiate pro-apoptotic pathways. It is suggested that 4-PBA may help fold proteins in the ER, attenuating the activation of the UPR, and thus potentially alleviating various pathologies. This review discusses the biomedical research exploring the potential therapeutic effects of 4-PBA in various in vitro and in vivo model systems and clinical trials, while also commenting on the possible mechanisms of action.
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Kuma A, Tamura M, Ishimatsu N, Miyamoto T, Serino R, Ishimori S, Morisada N, Iijima K, Yamada S, Takeuchi M, Abe H, Otsuji Y. A novel UMOD gene mutation associated with uromodulin-associated kidney disease in a young woman with moderate kidney dysfunction. Intern Med 2015; 54:631-5. [PMID: 25786455 DOI: 10.2169/internalmedicine.54.3151] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Uromodulin-associated kidney disease (UAKD) is an autosomal dominant disease caused by a mutation in the uromodulin (UMOD) gene, leading to end-stage renal disease. We herein report the case of a family with UAKD caused by a novel mutation (C135G) in the UMOD gene. A 31-year-old woman had a low estimated glomerular filtration rate (59.7 mL/min per 1.73 m(2)). Her father, grandfather and paternal aunt had received maintenance hemodialysis therapy since their 40's. This case underscores the importance of performing genetic testing in young patients even in cases involving only moderate abnormalities in the kidney function.
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Affiliation(s)
- Akihiro Kuma
- The Second Department of Internal Medicine, School of Medicine, University of Occupational and Environmental Health, Japan
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Padmanabhan S, Graham L, Ferreri NR, Graham D, McBride M, Dominiczak AF. Uromodulin, an Emerging Novel Pathway for Blood Pressure Regulation and Hypertension. Hypertension 2014; 64:918-23. [DOI: 10.1161/hypertensionaha.114.03132] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Affiliation(s)
- Sandosh Padmanabhan
- From the BHF Glasgow Cardiovascular Research Centre, Institute of Cardiovascular and Medical Sciences, University of Glasgow, Glasgow, United Kingdom (S.P., L.G., D.G., M.M., A.F.D.); and Department of Pharmacology, New York Medical College, Valhalla (N.R.F.)
| | - Lesley Graham
- From the BHF Glasgow Cardiovascular Research Centre, Institute of Cardiovascular and Medical Sciences, University of Glasgow, Glasgow, United Kingdom (S.P., L.G., D.G., M.M., A.F.D.); and Department of Pharmacology, New York Medical College, Valhalla (N.R.F.)
| | - Nicholas R. Ferreri
- From the BHF Glasgow Cardiovascular Research Centre, Institute of Cardiovascular and Medical Sciences, University of Glasgow, Glasgow, United Kingdom (S.P., L.G., D.G., M.M., A.F.D.); and Department of Pharmacology, New York Medical College, Valhalla (N.R.F.)
| | - Delyth Graham
- From the BHF Glasgow Cardiovascular Research Centre, Institute of Cardiovascular and Medical Sciences, University of Glasgow, Glasgow, United Kingdom (S.P., L.G., D.G., M.M., A.F.D.); and Department of Pharmacology, New York Medical College, Valhalla (N.R.F.)
| | - Martin McBride
- From the BHF Glasgow Cardiovascular Research Centre, Institute of Cardiovascular and Medical Sciences, University of Glasgow, Glasgow, United Kingdom (S.P., L.G., D.G., M.M., A.F.D.); and Department of Pharmacology, New York Medical College, Valhalla (N.R.F.)
| | - Anna F. Dominiczak
- From the BHF Glasgow Cardiovascular Research Centre, Institute of Cardiovascular and Medical Sciences, University of Glasgow, Glasgow, United Kingdom (S.P., L.G., D.G., M.M., A.F.D.); and Department of Pharmacology, New York Medical College, Valhalla (N.R.F.)
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Apoptosis induced by an uromodulin mutant C112Y and its suppression by topiroxostat. Clin Exp Nephrol 2014; 19:576-84. [DOI: 10.1007/s10157-014-1032-8] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2014] [Accepted: 09/09/2014] [Indexed: 12/26/2022]
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Interstitial calcinosis in renal papillae of genetically engineered mouse models: relation to Randall's plaques. Urolithiasis 2014; 43 Suppl 1:65-76. [PMID: 25096800 DOI: 10.1007/s00240-014-0699-3] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2013] [Accepted: 07/22/2014] [Indexed: 02/08/2023]
Abstract
Genetically engineered mouse models (GEMMs) have been highly instrumental in elucidating gene functions and molecular pathogenesis of human diseases, although their use in studying kidney stone formation or nephrolithiasis remains relatively limited. This review intends to provide an overview of several knockout mouse models that develop interstitial calcinosis in the renal papillae. Included herein are mice deficient for Tamm-Horsfall protein (THP; also named uromodulin), osteopontin (OPN), both THP and OPN, Na(+)-phosphate cotransporter Type II (Npt2a) and Na(+)/H(+) exchanger regulatory factor (NHERF-1). The baseline information of each protein is summarized, along with key morphological features of the interstitial calcium deposits in mice lacking these proteins. Attempts are made to correlate the papillary interstitial deposits found in GEMMs with Randall's plaques, the latter considered precursors of idiopathic calcium stones in patients. The pathophysiology that underlies the renal calcinosis in the knockout mice is also discussed wherever information is available. Not all the knockout models are allocated equal space because some are more extensively characterized than others. Despite the inroads already made, the exact physiological underpinning, origin, evolution and fate of the papillary interstitial calcinosis in the GEMMs remain incompletely defined. Greater investigative efforts are warranted to pin down the precise role of the papillary interstitial calcinosis in nephrolithiasis using the existing models. Additionally, more sophisticated, second-generation GEMMs that allow gene inactivation in a time-controlled manner and "compound mice" that bear several genetic alterations are urgently needed, in light of mounting evidence that nephrolithiasis is a multifactorial, multi-stage and polygenic disease.
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Uromodulin: old friend with new roles in health and disease. Pediatr Nephrol 2014; 29:1151-8. [PMID: 23880785 DOI: 10.1007/s00467-013-2563-z] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/29/2013] [Revised: 06/16/2013] [Accepted: 06/26/2013] [Indexed: 12/11/2022]
Abstract
The most abundant urinary protein, Tamm-Horsfall protein, later renamed uromodulin, is expressed exclusively by the thick ascending limb cells of the kidney and released into urine from the apical cell membrane. Uromodulin is believed to protect against urinary tract infections and stones, but its other physiologic functions have remained obscure until recently. Renewed interest in uromodulin has been brought about by the identification of uromodulin mutations as causes of a discrete group of diseases that are distinct from nephronophthisis. The three overlapping clinical uromodulin-associated kidney diseases (UAKD) are medullary cystic disease type 2, familial juvenile hyperuricemic nephropathy and glomerulocystic kidney disease. Previously thought of as "adult diseases", it is now recognized that they may also present in childhood and even in infancy. Common characteristics of all three diseases are autosomal dominant inheritance, unremarkable urine sediment and slow progression to end-stage renal disease (ESRD). They are frequently associated with hyperuricemia and gout. These diseases appear to result from failure of the mutant uromodulin to be incorporated into the apical cilium, thereby placing UAKD in the category of "ciliopathies". In addition to causing specific UAKD, certain uromodulin gene polymorphisms have been linked to ESRD in general, suggesting that uromodulin plays a modulatory role in kidney disease progression.
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Kemter E, Sklenak S, Rathkolb B, Hrabě de Angelis M, Wolf E, Aigner B, Wanke R. No amelioration of uromodulin maturation and trafficking defect by sodium 4-phenylbutyrate in vivo: studies in mouse models of uromodulin-associated kidney disease. J Biol Chem 2014; 289:10715-10726. [PMID: 24567330 DOI: 10.1074/jbc.m113.537035] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Uromodulin (UMOD)-associated kidney disease (UAKD) belongs to the hereditary progressive ER storage diseases caused by maturation defects of mutant UMOD protein. Current treatments of UAKD patients are symptomatic and cannot prevent disease progression. Two in vitro studies reported a positive effect of the chemical chaperone sodium 4-phenylbutyrate (4-PBA) on mutant UMOD maturation. Thus, 4-PBA was suggested as a potential treatment for UAKD. This study evaluated the effects of 4-PBA in two mouse models of UAKD. In contrast to previous in vitro studies, treatment with 4-PBA did not increase HSP70 expression or improve maturation and trafficking of mutant UMOD in vivo. Kidney function of UAKD mice was actually deteriorated by 4-PBA treatment. In transfected tubular epithelial cells, 4-PBA did not improve maturation but increased the expression level of both mutant and wild-type UMOD protein. Activation of NF-κB pathway in thick ascending limb of Henle's loop cells of UAKD mice was detected by increased abundance of RelB and phospho-IκB kinase α/β, an indirect activator of NF-κB. Furthermore, the abundance of NF-κB1 p105/p50, NF-κB2 p100/p52, and TRAF2 was increased in UAKD. NF-κB activation was identified as a novel disease mechanism of UAKD and might be a target for therapeutic intervention.
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Affiliation(s)
- Elisabeth Kemter
- Chair for Molecular Animal Breeding and Biotechnology, Gene Center, Ludwig-Maximilians-Universität München, 81377 Munich, Germany.
| | - Stefanie Sklenak
- Chair for Molecular Animal Breeding and Biotechnology, Gene Center, Ludwig-Maximilians-Universität München, 81377 Munich, Germany
| | - Birgit Rathkolb
- Chair for Molecular Animal Breeding and Biotechnology, Gene Center, Ludwig-Maximilians-Universität München, 81377 Munich, Germany; German Mouse Clinic, Institute of Experimental Genetics, Helmholtz Zentrum München, 85764 Neuherberg, Germany; German Research Center of Diabetes Research (DZD), Helmholtz Zentrum München, 85764 Neuherberg, Germany
| | - Martin Hrabě de Angelis
- German Mouse Clinic, Institute of Experimental Genetics, Helmholtz Zentrum München, 85764 Neuherberg, Germany; German Research Center of Diabetes Research (DZD), Helmholtz Zentrum München, 85764 Neuherberg, Germany
| | - Eckhard Wolf
- Chair for Molecular Animal Breeding and Biotechnology, Gene Center, Ludwig-Maximilians-Universität München, 81377 Munich, Germany
| | - Bernhard Aigner
- Chair for Molecular Animal Breeding and Biotechnology, Gene Center, Ludwig-Maximilians-Universität München, 81377 Munich, Germany
| | - Ruediger Wanke
- Institute of Veterinary Pathology, Center for Clinical Veterinary Medicine, Ludwig-Maximilians-Universität München, 80539 Munich, Germany
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Yang YM, Lane KB, Sehgal PB. Subcellular mechanisms in pulmonary arterial hypertension: combinatorial modalities that inhibit anterograde trafficking and cause bone morphogenetic protein receptor type 2 mislocalization. Pulm Circ 2013; 3:533-50. [PMID: 24618539 DOI: 10.1086/674336] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
Abstract
Abstract The natural history of familial pulmonary arterial hypertension (PAH) typically involves mutations in and/or haploinsuffciency of BMPR2 (gene for bone morphogenetic protein receptor type 2) but with low penetrance (10%-15%), delayed onset (in the third or fourth decade), and a gender bias (two- to fourfold more prevalent in postpubertal women). Thus, investigators have sought an understanding of "second-hit" modalities that might affect BMPR2 anterograde trafficking and/or function. Indeed, vascular lung lesions in PAH have been reported to contain enlarged "vacuolated" endothelial and smooth muscle cells with dilated endoplasmic reticulum (ER) cisternae, increased ER structural protein reticulon 4 (also called Nogo-B), and enlarged and fragmented Golgi apparatus. We recently replicated this cellular phenotype in primary human pulmonary arterial endothelial cells and human pulmonary arterial smooth muscle cells in culture by acute knockdown of the estradiol 17β (E2)-responsive proteins signal transducer and activator of transcription 5a (STAT5a) and STAT5b using small interfering RNAs (siRNAs). We have now investigated whether functional haploinsufficiences of these molecules, alone or in combination with other modalities, might interfere with anterograde membrane trafficking using (a) the quantitative tsO45VSV-G-GFP trafficking assay and (b) assays for cell-surface localization of Flag-tagged BMPR2 molecules. The G glycoprotein of the vesicular stomatitis virus (VSV-G) trafficking assay was validated in EA.hy926 endothelial cells by showing that cells exposed to monocrotaline pyrrole displayed reduced anterograde trafficking. Thereafter, the combinatorial knockdowns of STAT5a, STAT5b, BMPR2, and/or endothelial nitric oxide synthase as well as exposure to E2 or 2-methoxyestradiol were observed to significantly inhibit VSV-G trafficking. These combinations also led to intracellular trapping of wild-type Flag-tagged BMPR2. Overexpression of the PAH disease-derived F14 and KDF mutants of BMPR2, which were trapped in the ER/Golgi, also inhibited VSV-G trafficking in trans. Moreover, probenecid, a chemical chaperone in clinical use today, partially restored cell-surface localization of the KDF but not the F14 mutant. These data identify several combinatorial modalities that inhibit VSV-G anterograde trafficking and cause mislocalization of BMPR2. These modalities merit consideration in defining aspects of the late-developing and gender-biased natural history of human PAH.
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Affiliation(s)
- Yang-Ming Yang
- 1 Department of Cell Biology and Anatomy, New York Medical College, Valhalla, New York, USA
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Treatment with 17-allylamino-17-demethoxygeldanamycin ameliorated symptoms of Bartter syndrome type IV caused by mutated Bsnd in mice. Biochem Biophys Res Commun 2013; 441:544-9. [PMID: 24189473 DOI: 10.1016/j.bbrc.2013.10.129] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2013] [Accepted: 10/24/2013] [Indexed: 11/21/2022]
Abstract
Mutations of BSND, which encodes barttin, cause Bartter syndrome type IV. This disease is characterized by salt and fluid loss, hypokalemia, metabolic alkalosis, and sensorineural hearing impairment. Barttin is the β-subunit of the ClC-K chloride channel, which recruits it to the plasma membranes, and the ClC-K/barttin complex contributes to transepithelial chloride transport in the kidney and inner ear. The retention of mutant forms of barttin in the endoplasmic reticulum (ER) is etiologically linked to Bartter syndrome type IV. Here, we report that treatment with 17-allylamino-17-demethoxygeldanamycin (17-AAG), an Hsp90 inhibitor, enhanced the plasma membrane expression of mutant barttins (R8L and G47R) in Madin-Darby canine kidney cells. Administration of 17-AAG to Bsnd(R8L/R8L) knock-in mice elevated the plasma membrane expression of R8L in the kidney and inner ear, thereby mitigating hypokalemia, metabolic alkalosis, and hearing loss. These results suggest that drugs that rescue ER-retained mutant barttin may be useful for treating patients with Bartter syndrome type IV.
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