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Tabibzadeh N, Klein M, Try M, Poupon J, Houillier P, Klein C, Cheval L, Crambert G, Lasaad S, Chevillard L, Megarbane B. Low exposition to lithium prevents nephrogenic diabetes insipidus but not microcystic dilations of the collecting ducts in long-term rat model. Arch Pharm (Weinheim) 2024:e2400063. [PMID: 38704748 DOI: 10.1002/ardp.202400063] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2024] [Revised: 04/07/2024] [Accepted: 04/09/2024] [Indexed: 05/07/2024]
Abstract
Lithium induces nephrogenic diabetes insipidus (NDI) and microcystic chronic kidney disease (CKD). As previous clinical studies suggest that NDI is dose-dependent and CKD is time-dependent, we investigated the effect of low exposition to lithium in a long-term experimental rat model. Rats were fed with a normal diet (control group), with the addition of lithium (Li+ group), or with lithium and amiloride (Li+/Ami group) for 6 months, allowing obtaining low plasma lithium concentrations (0.25 ± 0.06 and 0.43 ± 0.16 mmol/L, respectively). Exposition to low concentrations of plasma lithium levels prevented NDI but not microcystic dilations of kidney tubules, which were identified as collecting ducts (CDs) on immunofluorescent staining. Both hypertrophy, characterized by an increase in the ratio of nuclei per tubular area, and microcystic dilations were observed. The ratio between principal cells and intercalated cells was higher in microcystic than in hypertrophied tubules. There was no correlation between AQP2 messenger RNA levels and cellular remodeling of the CD. Additional amiloride treatment in the Li+/Ami group did not allow consistent morphometric and cellular composition changes compared to the Li+ group. Low exposition to lithium prevented overt NDI but not microcystic dilations of the CD, with differential cellular composition in hypertrophied and microcystic CDs, suggesting different underlying cellular mechanisms.
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Affiliation(s)
- Nahid Tabibzadeh
- Laboratoire de Physiologie Rénale et Tubulopathies, Centre de Recherche des Cordeliers, INSERM, Sorbonne Université, Université Paris Cité, Paris, France
- EMR 8228 Unité Métabolisme et Physiologie Rénale, CNRS, Paris, France
| | - Mathieu Klein
- Inserm UMRS-1144, Université Paris Cité, Paris, France
| | - Mélanie Try
- Laboratoire de Physiologie Rénale et Tubulopathies, Centre de Recherche des Cordeliers, INSERM, Sorbonne Université, Université Paris Cité, Paris, France
- EMR 8228 Unité Métabolisme et Physiologie Rénale, CNRS, Paris, France
| | - Joël Poupon
- Department of Biological Toxicology, AP-HP, Lariboisière Hospital, University Paris VII, Paris, France
| | - Pascal Houillier
- Laboratoire de Physiologie Rénale et Tubulopathies, Centre de Recherche des Cordeliers, INSERM, Sorbonne Université, Université Paris Cité, Paris, France
- EMR 8228 Unité Métabolisme et Physiologie Rénale, CNRS, Paris, France
- Assistance Publique-Hôpitaux de Paris, Hôpital Européen Georges Pompidou, Service de Physiologie, Paris, France
| | - Christophe Klein
- Centre d'Histologie, d'Imagerie et de Cytométrie (CHIC), Centre de Recherche des Cordeliers, INSERM, Sorbonne Université, Université de Paris, Paris, France
| | - Lydie Cheval
- Laboratoire de Physiologie Rénale et Tubulopathies, Centre de Recherche des Cordeliers, INSERM, Sorbonne Université, Université Paris Cité, Paris, France
- EMR 8228 Unité Métabolisme et Physiologie Rénale, CNRS, Paris, France
| | - Gilles Crambert
- Laboratoire de Physiologie Rénale et Tubulopathies, Centre de Recherche des Cordeliers, INSERM, Sorbonne Université, Université Paris Cité, Paris, France
- EMR 8228 Unité Métabolisme et Physiologie Rénale, CNRS, Paris, France
| | - Samia Lasaad
- Laboratoire de Physiologie Rénale et Tubulopathies, Centre de Recherche des Cordeliers, INSERM, Sorbonne Université, Université Paris Cité, Paris, France
- EMR 8228 Unité Métabolisme et Physiologie Rénale, CNRS, Paris, France
| | | | - Bruno Megarbane
- Inserm UMRS-1144, Université Paris Cité, Paris, France
- Department of Medical and Toxicological Critical Care, Lariboisière Hospital, Federation of Toxicology, APHP, Paris, France
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2
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Yanda MK, Ciobanu C, Guggino WB, Cebotaru L. CFTR and PC2, partners in the primary cilia in autosomal dominant polycystic kidney disease. Am J Physiol Cell Physiol 2023; 325:C682-C693. [PMID: 37519231 PMCID: PMC10635646 DOI: 10.1152/ajpcell.00197.2023] [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: 05/09/2023] [Revised: 07/13/2023] [Accepted: 07/27/2023] [Indexed: 08/01/2023]
Abstract
Defects in the primary cilium are associated with autosomal dominant polycystic kidney disease (ADPKD). We used a combination of animal models, Western blotting, and confocal microscopy and discovered that CFTR and polycystin 2 (PC2) are both colocalized to the cilium in normal kidneys, with the levels of both being decreased in cystic epithelia. Cilia were longer in CFTR-null mice and in cystic cells in our ADPKD animal models. We examined septin 2, known to play a role in cilia length, to act as a diffusion barrier and to serve as an enhancer of proliferation. We found that septin 2 protein levels were upregulated and colocalized strongly with CFTR in cystic cells. Application of VX-809, the CFTR corrector, restored CFTR and PC2 toward normal in the cilia, decreased the protein levels of septin 2, and drastically reduced septin 2 colocalization with CFTR. Our data suggest that CFTR is present in the cilia and plays a role there, perhaps through its conductance of Cl-. We also postulate that septin 2 is important for localizing CFTR to the apical membrane in cystic epithelia.NEW & NOTEWORTHY CFTR is present in the primary cilia together with polycystin 2 (PC2). Ablation of CFTR makes cilia longer suggesting that CFTR plays a role there, perhaps through its conductance of Cl.
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Affiliation(s)
- Murali K Yanda
- The Johns Hopkins University School of Medicine, Baltimore, Maryland, United States
| | - Cristian Ciobanu
- The Johns Hopkins University School of Medicine, Baltimore, Maryland, United States
| | - William B Guggino
- The Johns Hopkins University School of Medicine, Baltimore, Maryland, United States
| | - Liudmila Cebotaru
- The Johns Hopkins University School of Medicine, Baltimore, Maryland, United States
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3
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Pyrshev K, Stavniichuk A, Tomilin VN, Khayyat NH, Ren G, Kordysh M, Zaika O, Mamenko M, Pochynyuk O. TRPV4 functional status in cystic cells regulates cystogenesis in autosomal recessive polycystic kidney disease during variations in dietary potassium. Physiol Rep 2023; 11:e15641. [PMID: 36946001 PMCID: PMC10031299 DOI: 10.14814/phy2.15641] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2023] [Revised: 02/23/2023] [Accepted: 02/24/2023] [Indexed: 03/23/2023] Open
Abstract
Mechanosensitive TRPV4 channel plays a dominant role in maintaining [Ca2+ ]i homeostasis and flow-sensitive [Ca2+ ]i signaling in the renal tubule. Polycystic kidney disease (PKD) manifests as progressive cyst growth due to cAMP-dependent fluid secretion along with deficient mechanosensitivity and impaired TRPV4 activity. Here, we tested how regulation of renal TRPV4 function by dietary K+ intake modulates the rate of cystogenesis and mechanosensitive [Ca2+ ]i signaling in cystic cells of PCK453 rats, a homologous model of human autosomal recessive PKD (ARPKD). One month treatment with both high KCl (5% K+ ) and KB/C (5% K+ with bicarbonate/citrate) diets significantly increased TRPV4 levels when compared to control (0.9% K+ ). High KCl diet caused an increased TRPV4-dependent Ca2+ influx, and partial restoration of mechanosensitivity in freshly isolated monolayers of cystic cells. Unexpectedly, high KB/C diet induced an opposite effect by reducing TRPV4 activity and worsening [Ca2+ ]i homeostasis. Importantly, high KCl diet decreased cAMP, whereas high KB/C diet further increased cAMP levels in cystic cells (assessed as AQP2 distribution). At the systemic level, high KCl diet fed PCK453 rats had significantly lower kidney-to-bodyweight ratio and reduced cystic area. These beneficial effects were negated by a concomitant administration of an orally active TRPV4 antagonist, GSK2193874, resulting in greater kidney weight, accelerated cystogenesis, and augmented renal injury. High KB/C diet also exacerbated renal manifestations of ARPKD, consistent with deficient TRPV4 activity in cystic cells. Overall, we demonstrate that TRPV4 channel activity negatively regulates cAMP levels in cystic cells thus attenuating (high activity) or accelerating (low activity) ARPKD progression.
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Affiliation(s)
- Kyrylo Pyrshev
- Department of Integrative Biology and PharmacologyThe University of Texas Health Science Center at HoustonHoustonTexasUSA
| | - Anna Stavniichuk
- Department of Integrative Biology and PharmacologyThe University of Texas Health Science Center at HoustonHoustonTexasUSA
| | - Viktor N. Tomilin
- Department of Integrative Biology and PharmacologyThe University of Texas Health Science Center at HoustonHoustonTexasUSA
| | - Naghmeh Hassanzadeh Khayyat
- Department of Integrative Biology and PharmacologyThe University of Texas Health Science Center at HoustonHoustonTexasUSA
| | - Guohui Ren
- Department of Integrative Biology and PharmacologyThe University of Texas Health Science Center at HoustonHoustonTexasUSA
| | - Mariya Kordysh
- Department of Integrative Biology and PharmacologyThe University of Texas Health Science Center at HoustonHoustonTexasUSA
| | - Oleg Zaika
- Department of Integrative Biology and PharmacologyThe University of Texas Health Science Center at HoustonHoustonTexasUSA
| | - Mykola Mamenko
- Department of PhysiologyAugusta UniversityAugustaGeorgiaUSA
| | - Oleh Pochynyuk
- Department of Integrative Biology and PharmacologyThe University of Texas Health Science Center at HoustonHoustonTexasUSA
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4
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Zhang J, Chen J, Xu J, Xue C, Mao Z. Plant-derived compounds for treating autosomal dominant polycystic kidney disease. FRONTIERS IN NEPHROLOGY 2023; 3:1071441. [PMID: 37675342 PMCID: PMC10479581 DOI: 10.3389/fneph.2023.1071441] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/16/2022] [Accepted: 01/12/2023] [Indexed: 09/08/2023]
Abstract
Autosomal dominant polycystic kidney disease (ADPKD), the most common monogenic hereditary kidney disease, is the fourth leading cause of end-stage kidney disease worldwide. In recent years, significant progress has been made in delaying ADPKD progression with different kinds of chemical drugs, such as tolvaptan, rapamycin, and somatostatin. Meanwhile, numerous plant-derived compounds have been investigated for their beneficial effects on slowing ADPKD progression. Among them, saikosaponin-d, Ganoderma triterpenes, curcumin, ginkgolide B, steviol, resveratrol, Sparganum stoloniferum Buch.-Ham, Cordyceps sinensis, triptolide, quercitrin, naringin, cardamonin, gambogic acid, and olive leaf extract have been found to retard renal cyst development by inhibiting cell proliferation or promoting cell apoptosis in renal cyst-lining epithelial cells. Metformin, a synthesized compound derived from French lilac or goat's rue (Galega officinalis), has been proven to retard the progression of ADPKD. This review focuses on the roles and mechanisms of plant-derived compounds in treating ADPKD, which may constitute promising new therapeutics in the future.
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Affiliation(s)
- Jieting Zhang
- School of Medicine, Shanghai University, Shanghai, China
- Division of Nephrology, Shanghai Changzheng Hospital, Second Military Medical University, Shanghai, China
| | - Jiaxin Chen
- Division of Nephrology, Shanghai Changzheng Hospital, Second Military Medical University, Shanghai, China
| | - Jing Xu
- Division of Nephrology, Shanghai Changzheng Hospital, Second Military Medical University, Shanghai, China
| | - Cheng Xue
- Division of Nephrology, Shanghai Changzheng Hospital, Second Military Medical University, Shanghai, China
| | - Zhiguo Mao
- Division of Nephrology, Shanghai Changzheng Hospital, Second Military Medical University, Shanghai, China
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5
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Choudhury MI, Li Y, Mistriotis P, Vasconcelos ACN, Dixon EE, Yang J, Benson M, Maity D, Walker R, Martin L, Koroma F, Qian F, Konstantopoulos K, Woodward OM, Sun SX. Kidney epithelial cells are active mechano-biological fluid pumps. Nat Commun 2022; 13:2317. [PMID: 35484146 PMCID: PMC9050750 DOI: 10.1038/s41467-022-29988-w] [Citation(s) in RCA: 23] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2021] [Accepted: 04/08/2022] [Indexed: 12/11/2022] Open
Abstract
The role of mechanical forces driving kidney epithelial fluid transport and morphogenesis in kidney diseases is unclear. Here, using a microfluidic platform to recapitulate fluid transport activity of kidney cells, we report that renal epithelial cells can actively generate hydraulic pressure gradients across the epithelium. The fluidic flux declines with increasing hydraulic pressure until a stall pressure, in a manner similar to mechanical fluid pumps. For normal human kidney cells, the fluidic flux is from apical to basal, and the pressure is higher on the basal side. For human Autosomal Dominant Polycystic Kidney Disease cells, the fluidic flux is reversed from basal to apical. Molecular and proteomic studies reveal that renal epithelial cells are sensitive to hydraulic pressure gradients, changing gene expression profiles and spatial arrangements of ion exchangers and the cytoskeleton in different pressure conditions. These results implicate mechanical force and hydraulic pressure as important variables during kidney function and morphological change, and provide insights into pathophysiological mechanisms underlying the development and transduction of hydraulic pressure gradients. How mechanical forces drive fluid transport in the kidney remains unclear. Here, the authors use a microfluidic platform to show that kidney epithelial cells generate hydraulic pressure gradients across the epithelium, and that the fluid flux is from apical to basal for normal cells, and inverted in autosomal dominant polycystic kidney disease cells.
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Affiliation(s)
- Mohammad Ikbal Choudhury
- Department of Mechanical Engineering, Johns Hopkins University, Baltimore, MD, United States.,Institute of NanoBioTechnology, Johns Hopkins University, Baltimore, MD, United States
| | - Yizeng Li
- Department of Mechanical Engineering, Johns Hopkins University, Baltimore, MD, United States.,Department of Mechanical Engineering, Kennesaw State University, Marietta, GA, United States
| | - Panagiotis Mistriotis
- Department of Chemical and Biomolecular Engineering, Johns Hopkins University, Baltimore, MD, United States.,Department of Chemical Engineering, Auburn University, Auburn, AL, United States
| | - Ana Carina N Vasconcelos
- Department of Mechanical Engineering, Johns Hopkins University, Baltimore, MD, United States.,Institute of NanoBioTechnology, Johns Hopkins University, Baltimore, MD, United States
| | - Eryn E Dixon
- Department of Biochemistry and Molecular Biology, Maryland PKD Research and Clinical Core Center, University of Maryland School of Medicine, Baltimore, MD, United States.,Department of Physiology, Maryland PKD Research and Clinical Core Center, University of Maryland School of Medicine, Baltimore, MD, United States.,Maryland PKD Research and Clinical Core Center, University of Maryland School of Medicine, Baltimore, MD, United States
| | - Jing Yang
- Department of Mechanical Engineering, Johns Hopkins University, Baltimore, MD, United States.,Institute of NanoBioTechnology, Johns Hopkins University, Baltimore, MD, United States
| | - Morgan Benson
- Institute of NanoBioTechnology, Johns Hopkins University, Baltimore, MD, United States.,Department of Chemical and Biomolecular Engineering, Johns Hopkins University, Baltimore, MD, United States
| | - Debonil Maity
- Institute of NanoBioTechnology, Johns Hopkins University, Baltimore, MD, United States.,Department of Chemical and Biomolecular Engineering, Johns Hopkins University, Baltimore, MD, United States
| | - Rebecca Walker
- Department of Biochemistry and Molecular Biology, Maryland PKD Research and Clinical Core Center, University of Maryland School of Medicine, Baltimore, MD, United States.,Maryland PKD Research and Clinical Core Center, University of Maryland School of Medicine, Baltimore, MD, United States
| | - Leigha Martin
- Department of Chemical and Biomolecular Engineering, Johns Hopkins University, Baltimore, MD, United States
| | - Fatima Koroma
- Department of Chemical and Biomolecular Engineering, Johns Hopkins University, Baltimore, MD, United States
| | - Feng Qian
- Department of Biochemistry and Molecular Biology, Maryland PKD Research and Clinical Core Center, University of Maryland School of Medicine, Baltimore, MD, United States.,Maryland PKD Research and Clinical Core Center, University of Maryland School of Medicine, Baltimore, MD, United States
| | - Konstantinos Konstantopoulos
- Institute of NanoBioTechnology, Johns Hopkins University, Baltimore, MD, United States.,Department of Chemical and Biomolecular Engineering, Johns Hopkins University, Baltimore, MD, United States
| | - Owen M Woodward
- Department of Physiology, Maryland PKD Research and Clinical Core Center, University of Maryland School of Medicine, Baltimore, MD, United States.,Maryland PKD Research and Clinical Core Center, University of Maryland School of Medicine, Baltimore, MD, United States
| | - Sean X Sun
- Department of Mechanical Engineering, Johns Hopkins University, Baltimore, MD, United States. .,Institute of NanoBioTechnology, Johns Hopkins University, Baltimore, MD, United States.
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6
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Pastor-Soler NM, Li H, Pham J, Rivera D, Ho PY, Mancino V, Saitta B, Hallows KR. Metformin improves relevant disease parameters in an autosomal dominant polycystic kidney disease mouse model. Am J Physiol Renal Physiol 2022; 322:F27-F41. [PMID: 34806449 DOI: 10.1152/ajprenal.00298.2021] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2021] [Accepted: 11/10/2021] [Indexed: 12/14/2022] Open
Abstract
Autosomal dominant polycystic kidney disease (ADPKD), caused by mutations in the polycystin 1 (PKD1) or polycystin 2 genes, presents with progressive development of kidney cysts and eventual end-stage kidney disease with limited treatment options. Previous work has shown that metformin reduces cyst growth in rapid ADPKD mouse models via inhibition of cystic fibrosis transmembrane conductance regulator-mediated fluid secretion, mammalian target of rapamycin, and cAMP pathways. The present study importantly tested the effectiveness of metformin as a therapy for ADPKD in a more clinically relevant Pkd1RC/RC mouse model, homozygous for the R3277C knockin point mutation in the Pkd1 gene. This mutation causes ADPKD in humans. Pkd1RC/RC male and female mice, which have a slow progression to end-stage kidney disease, received metformin (300 mg/kg/day in drinking water vs. water alone) from 3 to 9 or 12 mo of age. As previously reported, Pkd1RC/RC females had a more severe disease phenotype as compared with males. Metformin treatment reduced the ratio of total kidney weight-to-body weight relative to age-matched and sex-matched untreated controls at both 9 and 12 mo and reduced the cystic index in females at 9 mo. Metformin also increased glomerular filtration rate, lowered systolic blood pressure, improved anemia, and lowered blood urea nitrogen levels relative to controls in both sexes. Moreover, metformin reduced gene expression of key inflammatory markers and both gene and protein expression of kidney injury marker-1 and cyclin-dependent kinase-1 versus untreated controls. Altogether, these findings suggest several beneficial effects of metformin in this highly relevant slowly progressive ADPKD mouse model, which may help inform new ADPKD therapies in patients.NEW & NOTEWORTHY Metformin treatment improved ADPKD disease severity in a relevant, slowly progressive ADPKD mouse model that recapitulates a PKD-associated PKD1 mutation. Relative to controls, metformin reduced kidney weight/body weight, cystic index and BUN levels, while improving GFR, blood pressure and anemia. Metformin also reduced key inflammatory and injury markers, along with cell proliferation markers. These findings suggest several beneficial effects of metformin in this ADPKD mouse model, which may help inform new ADPKD therapies in patients.
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MESH Headings
- Animals
- Cell Proliferation/drug effects
- Disease Models, Animal
- Disease Progression
- Female
- Genetic Predisposition to Disease
- Glomerular Filtration Rate/drug effects
- Inflammation Mediators/metabolism
- Kidney/drug effects
- Kidney/metabolism
- Kidney/pathology
- Kidney/physiopathology
- Kidney Failure, Chronic/metabolism
- Kidney Failure, Chronic/pathology
- Kidney Failure, Chronic/physiopathology
- Kidney Failure, Chronic/prevention & control
- Male
- Metformin/pharmacology
- Mice, 129 Strain
- Mice, Inbred C57BL
- Mice, Transgenic
- Mutation
- Polycystic Kidney, Autosomal Dominant/drug therapy
- Polycystic Kidney, Autosomal Dominant/metabolism
- Polycystic Kidney, Autosomal Dominant/pathology
- Polycystic Kidney, Autosomal Dominant/physiopathology
- Renal Agents/pharmacology
- TRPP Cation Channels/genetics
- Time Factors
- Mice
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Affiliation(s)
- Núria M Pastor-Soler
- Division of Nephrology and Hypertension, Department of Medicine and USC/UKRO Kidney Research Center, Keck School of Medicine, University of Southern California, Los Angeles, California
| | - Hui Li
- Division of Nephrology and Hypertension, Department of Medicine and USC/UKRO Kidney Research Center, Keck School of Medicine, University of Southern California, Los Angeles, California
| | - Jessica Pham
- Division of Nephrology and Hypertension, Department of Medicine and USC/UKRO Kidney Research Center, Keck School of Medicine, University of Southern California, Los Angeles, California
| | - Daniel Rivera
- Division of Nephrology and Hypertension, Department of Medicine and USC/UKRO Kidney Research Center, Keck School of Medicine, University of Southern California, Los Angeles, California
| | - Pei-Yin Ho
- Division of Nephrology and Hypertension, Department of Medicine and USC/UKRO Kidney Research Center, Keck School of Medicine, University of Southern California, Los Angeles, California
| | - Valeria Mancino
- Division of Nephrology and Hypertension, Department of Medicine and USC/UKRO Kidney Research Center, Keck School of Medicine, University of Southern California, Los Angeles, California
| | - Biagio Saitta
- Division of Nephrology and Hypertension, Department of Medicine and USC/UKRO Kidney Research Center, Keck School of Medicine, University of Southern California, Los Angeles, California
| | - Kenneth R Hallows
- Division of Nephrology and Hypertension, Department of Medicine and USC/UKRO Kidney Research Center, Keck School of Medicine, University of Southern California, Los Angeles, California
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7
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Gupta S, Ozimek-Kulik JE, Phillips JK. Nephronophthisis-Pathobiology and Molecular Pathogenesis of a Rare Kidney Genetic Disease. Genes (Basel) 2021; 12:genes12111762. [PMID: 34828368 PMCID: PMC8623546 DOI: 10.3390/genes12111762] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2021] [Revised: 10/26/2021] [Accepted: 10/27/2021] [Indexed: 12/17/2022] Open
Abstract
The exponential rise in our understanding of the aetiology and pathophysiology of genetic cystic kidney diseases can be attributed to the identification of cystogenic genes over the last three decades. The foundation of this was laid by positional cloning strategies which gradually shifted towards next-generation sequencing (NGS) based screenings. This shift has enabled the discovery of novel cystogenic genes at an accelerated pace unlike ever before and, most notably, the past decade has seen the largest increase in identification of the genes which cause nephronophthisis (NPHP). NPHP is a monogenic autosomal recessive cystic kidney disease caused by mutations in a diverse clade of over 26 identified genes and is the most common genetic cause of renal failure in children. NPHP gene types present with some common pathophysiological features alongside a diverse range of extra-renal phenotypes associated with specific syndromic presentations. This review provides a timely update on our knowledge of this disease, including epidemiology, pathophysiology, anatomical and molecular features. We delve into the diversity of the NPHP causing genes and discuss known molecular mechanisms and biochemical pathways that may have possible points of intersection with polycystic kidney disease (the most studied renal cystic pathology). We delineate the pathologies arising from extra-renal complications and co-morbidities and their impact on quality of life. Finally, we discuss the current diagnostic and therapeutic modalities available for disease management, outlining possible avenues of research to improve the prognosis for NPHP patients.
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Affiliation(s)
- Shabarni Gupta
- Macquarie Medical School, Faculty of Medicine, Health and Human Sciences, Macquarie University, Sydney, NSW 2109, Australia; (J.E.O.-K.); (J.K.P.)
- Correspondence:
| | - Justyna E. Ozimek-Kulik
- Macquarie Medical School, Faculty of Medicine, Health and Human Sciences, Macquarie University, Sydney, NSW 2109, Australia; (J.E.O.-K.); (J.K.P.)
- School of Women’s and Children’s Health, University of New South Wales, Sydney, NSW 2031, Australia
- Department of Paediatric Nephrology, Sydney Children’s Hospital Network, Children’s Hospital at Westmead, Sydney, NSW 2145, Australia
| | - Jacqueline Kathleen Phillips
- Macquarie Medical School, Faculty of Medicine, Health and Human Sciences, Macquarie University, Sydney, NSW 2109, Australia; (J.E.O.-K.); (J.K.P.)
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8
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Olesen ETB, Fenton RA. Aquaporin 2 regulation: implications for water balance and polycystic kidney diseases. Nat Rev Nephrol 2021; 17:765-781. [PMID: 34211154 DOI: 10.1038/s41581-021-00447-x] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/21/2021] [Indexed: 02/06/2023]
Abstract
Targeting the collecting duct water channel aquaporin 2 (AQP2) to the plasma membrane is essential for the maintenance of mammalian water homeostasis. The vasopressin V2 receptor (V2R), which is a GS protein-coupled receptor that increases intracellular cAMP levels, has a major role in this targeting process. Although a rise in cAMP levels and activation of protein kinase A are involved in facilitating the actions of V2R, studies in knockout mice and cell models have suggested that cAMP signalling pathways are not an absolute requirement for V2R-mediated AQP2 trafficking to the plasma membrane. In addition, although AQP2 phosphorylation is a known prerequisite for V2R-mediated plasma membrane targeting, none of the known AQP2 phosphorylation events appears to be rate-limiting in this process, which suggests the involvement of other factors; cytoskeletal remodelling has also been implicated. Notably, several regulatory processes and signalling pathways involved in AQP2 trafficking also have a role in the pathophysiology of autosomal dominant polycystic kidney disease, although the role of AQP2 in cyst progression is unknown. Here, we highlight advances in the field of AQP2 regulation that might be exploited for the treatment of water balance disorders and provide a rationale for targeting these pathways in autosomal dominant polycystic kidney disease.
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Affiliation(s)
- Emma T B Olesen
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark. .,Department of Endocrinology and Nephrology, North Zealand Hospital, Hillerød, Denmark.
| | - Robert A Fenton
- Department of Biomedicine, Faculty of Health, Aarhus University, Aarhus, Denmark.
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9
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Yanda MK, Cebotaru L. VX-809 mitigates disease in a mouse model of autosomal dominant polycystic kidney disease bearing the R3277C human mutation. FASEB J 2021; 35:e21987. [PMID: 34662459 DOI: 10.1096/fj.202101315r] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2021] [Revised: 09/20/2021] [Accepted: 09/28/2021] [Indexed: 12/11/2022]
Abstract
Autosomal dominant polycystic kidney disease (ADPKD) is associated with the formation of renal cysts. We have devised a therapeutic approach, based on reversing the cyst phenotype from secretion to absorption by using VX-809, a modulator of the cystic fibrosis transmembrane regulator trafficking and processing. Our goal is to test VX-809 in RC/RC mice bearing the R3277C human mutation to demonstrate its therapeutic potential. We found that by 5 months of age, RC/RC mice had large cysts and impaired renal function, but when treated with VX-809 between the ages of 3 and 5 months, or 6 and 8 months, the cyst area was reduced in both groups, suggesting that VX-809 had shrunk previously existing cysts. After 2 months of treatment, the cyst size was lower than that of untreated animals of the same age. Our co-localization studies confirmed that cystic fibrosis transmembrane conductance regulator (CFTR) is found predominately at the apical membrane in the untreated animals of each age group, consistent with its role in Cl- secretion; after VX-809 treatment, the basolateral membrane co-localization of CFTR increased ~4-fold, accompanied by a decrease of ~2-3-fold in its apical co-localization, indicating that VX-809 alters the phenotype to favor fluid absorption. Sodium/hydrogen exchanger and epithelial sodium channel, found in normal kidneys at the apical membrane, were almost absent from the cysts. VX-809 restored both levels toward normal. HSP27 is highly expressed in RC/RC mice and lowered toward normal by VX-809. Our demonstration of cyst reduction, improved renal function, and generation of an absorptive phenotype all strongly support the therapeutic potential of VX-809 as a treatment for ADPKD. We show here in an animal model of slowly progressing cyst formation typical of human ADPKD that VX-809 reduces the growth of already established cysts. The magnitude of the effect in the RC/RC mouse model when compared to previous experiments using the same mouse model to evaluate tolvaptan indicates that CFTR modulators warrant further development as a treatment for ADPKD.
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Affiliation(s)
- Murali K Yanda
- Division of Gastroenterology and Hepatology, Department of Medicine, The Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Liudmila Cebotaru
- Division of Gastroenterology and Hepatology, Department of Medicine, The Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
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10
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Lindinger MI, Waller AP. Tracing oral Na
+
and K
+
in sweat during exercise and recovery in horses. Exp Physiol 2021; 106:972-982. [DOI: 10.1113/ep089232] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2020] [Accepted: 02/02/2021] [Indexed: 11/08/2022]
Affiliation(s)
- Michael I. Lindinger
- Research and Development The Nutraceutical Alliance Inc. Burlington Ontario Canada
| | - Amanda P. Waller
- Center for Clinical & Translational Research Nationwide Children's Hospital Columbus OH USA
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11
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Raby KL, Horsely H, McCarthy-Boxer A, Norman JT, Wilson PD. Urinary exosome proteomic profiling defines stage-specific rapid progression of autosomal dominant polycystic kidney disease and tolvaptan efficacy. BBA ADVANCES 2021; 1:100013. [PMID: 37082007 PMCID: PMC10074914 DOI: 10.1016/j.bbadva.2021.100013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2021] [Revised: 04/27/2021] [Accepted: 04/27/2021] [Indexed: 11/17/2022] Open
Abstract
ADPKD is the most common genetic disease of the kidney leading to end-stage renal disease necessitating renal replacement therapy at any time between the 1st and 8th decades of life due to widely variable rates of disease progression. This presents significant patient anxiety and a significant prognostic and therapeutic challenge. Tolvaptan is the only approved drug licensed to slow ADPKD progression by reducing renal cystic expansion but side-effects can limit its efficacy. To address the need to identify new biomarkers to monitor progression of ADPKD and to evaluate the therapeutic effects of Tolvaptan, proteomic analysis was conducted on defined (40-100nm) urinary exosomes isolated from ADPKD patients phenotyped and clinically monitored over a 10-year period. Comparative Gene Ontology analysis of Tandem Mass Tag labelled mass spectrometry-derived protein profiles from urinary exosomes from ADPKD patients with rapid (>10ml/min/5 years decline in estimated glomerular filtration rate) versus slow progression showed distinctive patterns of pathway up-regulation. Clear discrimination between rapid and slowly-progressive profiles were seen in all stages functional decline in ADPKD patients whether with mild (>70ml/min), moderate (50-69ml/min) or severe (<49ml/min) disease at onset. Discriminatory pathways and proteins included Notch-, integrin- and growth factor-signalling; microtubular kinase, vesicular proteins and epidermal growth factor substrates. Confocal microscopy of fluorescently-labelled normal versus ADPKD epithelial cell-derived exosomes in vitro also identified ADPKD-dependent abnormalities in intracellular vesicular trafficking and implicated changes in ADPKD-dependent exosome secretion and target cell uptake as factors underlying urinary exosome excretion biomarker properties. Comparative proteomic analysis of urinary exosomal proteins in individual patients before and after treatment with Tolvaptan for 4 years also identified distinct patterns of pathway modification dependent on the degree of effectiveness of the therapeutic response. Up-regulation of Wnt-pathway and vesicular proteins were characteristic of urinary exosomes from ADPKD patients with good responses to Tolvaptan while upregulation of angiogenesis pathways and additional molecular forms of vasopressin receptor AVPR2 were characteristic in urinary exosomes of ADPKD patients with poor responses. Taken together, these studies conclude that proteomic profiling of urinary exosome biomarkers provides a specific, sensitive and practical non-invasive method to identify and monitor the rate of disease progression and the effects of Tolvaptan therapy in individual ADPKD patients. This provides a means to identify those patients most likely to benefit maximally from therapy and to progress towards a personalization of ADPKD prognosis and management.
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Affiliation(s)
| | | | | | | | - Patricia D. Wilson
- Corresponding author at: University College London, Department of Renal Medicine, 2 Floor, Royal Free Hospital, Rowland Hill Street, London NW3 2PF, United Kingdom.
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12
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Jouret F, Devuyst O. Targeting chloride transport in autosomal dominant polycystic kidney disease. Cell Signal 2020; 73:109703. [PMID: 32619563 DOI: 10.1016/j.cellsig.2020.109703] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2020] [Revised: 06/25/2020] [Accepted: 06/26/2020] [Indexed: 02/07/2023]
Abstract
Autosomal dominant polycystic kidney disease (ADPKD) is the most frequent inherited kidney disease. Transepithelial fluid secretion is one of the key factors of cystogenesis in ADPKD. Multiple studies have suggested that fluid secretion across ADPKD cyst-lining cells is driven by the secretion of chloride, essentially mediated by the CFTR channel and stimulated by increased intracellular levels of 3',5'-cyclic adenosine monophosphate. This review focuses on the pathophysiology of fluid secretion in ADPKD based on the pioneering studies of Jared Grantham and colleagues, and on the follow-up investigations from the molecular level to the potential applications in ADPKD patients. Altogether, the studies of fluid and chloride transport in ADPKD paved the way for innovative therapeutic targets to prevent cyst volume expansion and thus, kidney disease progression.
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Affiliation(s)
- François Jouret
- Division of Nephrology, Department of Internal Medicine, ULiège Academic Hospital, Liège, Belgium,; Groupe Interdisciplinaire de Géno-protéomique Appliquée, Cardiovascular Sciences, ULiège Medical School, Liège, Belgium
| | - Olivier Devuyst
- Division of Nephrology, UCLouvain Medical School, B-1200, Brussels, Belgium,; Mechanisms of Inherited Kidney Disorders, University of Zurich, CH-8057 Zurich, Switzerland.
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13
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Sussman CR, Wang X, Chebib FT, Torres VE. Modulation of polycystic kidney disease by G-protein coupled receptors and cyclic AMP signaling. Cell Signal 2020; 72:109649. [PMID: 32335259 DOI: 10.1016/j.cellsig.2020.109649] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2020] [Revised: 04/16/2020] [Accepted: 04/17/2020] [Indexed: 12/11/2022]
Abstract
Autosomal Dominant Polycystic Kidney Disease (ADPKD) is a systemic disorder associated with polycystic liver disease (PLD) and other extrarenal manifestations, the most common monogenic cause of end-stage kidney disease, and a major burden for public health. Many studies have shown that alterations in G-protein and cAMP signaling play a central role in its pathogenesis. As for many other diseases (35% of all approved drugs target G-protein coupled receptors (GPCRs) or proteins functioning upstream or downstream from GPCRs), treatments targeting GPCR have shown effectiveness in slowing the rate of progression of ADPKD. Tolvaptan, a vasopressin V2 receptor antagonist is the first drug approved by regulatory agencies to treat rapidly progressive ADPKD. Long-acting somatostatin analogs have also been effective in slowing the rates of growth of polycystic kidneys and liver. Although no treatment has so far been able to prevent the development or stop the progression of the disease, these encouraging advances point to G-protein and cAMP signaling as a promising avenue of investigation that may lead to more effective and safe treatments. This will require a better understanding of the relevant GPCRs, G-proteins, cAMP effectors, and of the enzymes and A-kinase anchoring proteins controlling the compartmentalization of cAMP signaling. The purpose of this review is to provide an overview of general GPCR signaling; the function of polycystin-1 (PC1) as a putative atypical adhesion GPCR (aGPCR); the roles of PC1, polycystin-2 (PC2) and the PC1-PC2 complex in the regulation of calcium and cAMP signaling; the cross-talk of calcium and cAMP signaling in PKD; and GPCRs, adenylyl cyclases, cyclic nucleotide phosphodiesterases, and protein kinase A as therapeutic targets in ADPKD.
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Affiliation(s)
- Caroline R Sussman
- Division of Nephrology and Hypertension, Mayo Clinic, Rochester, MN, United States of America
| | - Xiaofang Wang
- Division of Nephrology and Hypertension, Mayo Clinic, Rochester, MN, United States of America
| | - Fouad T Chebib
- Division of Nephrology and Hypertension, Mayo Clinic, Rochester, MN, United States of America
| | - Vicente E Torres
- Division of Nephrology and Hypertension, Mayo Clinic, Rochester, MN, United States of America.
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14
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Yanda MK, Cha B, Cebotaru CV, Cebotaru L. Pharmacological reversal of renal cysts from secretion to absorption suggests a potential therapeutic strategy for managing autosomal dominant polycystic kidney disease. J Biol Chem 2019; 294:17090-17104. [PMID: 31570523 DOI: 10.1074/jbc.ra119.010320] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2019] [Revised: 09/26/2019] [Indexed: 12/19/2022] Open
Abstract
Autosomal-dominant polycystic kidney disease (ADPKD) induces a secretory phenotype, resulting in multiple fluid-filled cysts. We have previously demonstrated that VX-809, a corrector of the cystic fibrosis transmembrane conductance regulator (CFTR), reduces cyst growth. Here, we show that in normal mice CFTR is located within the cells and also at the apical and basolateral membranes. However, in polycystic kidney disease (pkd1)-knockout mice, CFTR was located at the plasma membrane, consistent with its role in cAMP-dependent fluid secretion. In cystic mice, VX-809 treatment increased CFTR levels at the apical membrane and reduced its association with the endoplasmic reticulum. Surprisingly, VX-809 treatment significantly increased CFTR's co-localization with the basolateral membrane in cystic mice. Na+/H+ exchanger 3 (NHE3) is present in pkd1-knockout and normal mice and in proximal tubule-derived, cultured pkd1-knockout cells. VX-809 increased the expression, activity, and apical plasma membrane localization of NHE3. Co-localization of epithelial sodium channel (ENaC) with the plasma membrane was reduced in cysts in pkd1-knockout mice, consistent with an inability of the cysts to absorb fluid. Interestingly, in the cystic mice, VX-809 treatment increased ENaC levels at the apical plasma membrane consistent with fluid absorption. Thus, VX-809 treatment of pkd1-null mouse kidneys significantly affected CFTR, NHE3, and ENaC, altering the cyst phenotype from one poised toward fluid secretion toward one more favorable for absorption. VX-809 also altered the location of CFTR but not of NHE3 or ENaC in normal mice. Given that VX-809 administration is safe, it may have potential utility for treating patients with ADPKD.
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Affiliation(s)
- Murali K Yanda
- Department of Medicine, The Johns Hopkins University School of Medicine, Baltimore, Maryland 21205
| | - Boyoung Cha
- Department of Medicine, The Johns Hopkins University School of Medicine, Baltimore, Maryland 21205
| | - Cristina V Cebotaru
- Department of Medicine, The Johns Hopkins University School of Medicine, Baltimore, Maryland 21205
| | - Liudmila Cebotaru
- Department of Medicine, The Johns Hopkins University School of Medicine, Baltimore, Maryland 21205
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15
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Abstract
Autosomal dominant polycystic kidney disease (ADPKD) is a common genetic disorder characterized by bilateral fluid-filled cysts, renal inflammation and extensive fibrosis, leading to the progressive decline in kidney function. Renal cyst formation begins in utero from aberrant proliferation of tubule epithelial cells; however, the mechanisms for cystogenesis remain unclear. Cell proliferation and Cl--dependent fluid secretion, which drives the accumulation of cyst fluid, are responsible for inexorable growth of cysts and the remarkable appearance of massively enlarged ADPKD kidneys. Investigators have used in vitro assays to explore cellular and molecular mechanisms involved in ADPKD cyst epithelial cell proliferation and Cl--dependent fluid secretion in experimentally controlled environments. These assays have been used to evaluate potential therapeutic approaches to inhibit cellular pathways involved in cyst growth. This chapter discusses methods for measuring ADPKD cell proliferation, transepithelial Cl- secretion, and net fluid transport across cyst epithelial cell monolayers.
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Affiliation(s)
- Gail A Reif
- Departments of Internal Medicine and Molecular and Integrative Physiology, and The Jared Grantham Kidney Institute, University of Kansas Medical Center, Kansas City, KS, United States
| | - Darren P Wallace
- Departments of Internal Medicine and Molecular and Integrative Physiology, and The Jared Grantham Kidney Institute, University of Kansas Medical Center, Kansas City, KS, United States.
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16
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Abstract
Autosomal dominant polycystic kidney disease (ADPKD) is a common genetic disorder characterized by the relentless growth of numerous fluid-filled cysts in the kidneys. Mutations in PKD1 and PKD2, genes that encode polycystin 1 and 2, respectively, are responsible for most cases of ADPKD. Currently, the cellular mechanisms responsible for cyst formation remain poorly understood. In vitro models have been used by researchers to investigate cellular processes for cyst formation in carefully controlled experimental conditions. Madin-Darby canine kidney (MDCK) cells, a distal tubule epithelial cell line, were first used to form 3-dimensional (3-D) cysts within a hydrated collagen gel. This method was applied to epithelial cells cultured from cysts of human ADPKD kidneys, allowing investigators to study cellular mechanisms for cyst growth using cells that harbor the genetic mutations responsible for ADPKD in humans. Studies using ADPKD in vitro cysts have provided insight into cellular processes regulating cell proliferation, fluid secretion, and cell polarity. These assays were used to demonstrate the central role of cAMP agonists, such as arginine vasopressin, on cyst growth; and to test the effectiveness of potential therapeutic agents, including tolvaptan. Results obtained from in vitro cyst experiments demonstrate the translational value of cell model systems for investigating the mechanisms for cyst formation in human ADPKD. In this chapter, we describe protocols for growing ADPKD cells in a 3-D in vitro cyst assay and measuring total cyst volume by microscopy and image analysis.
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17
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Ilatovskaya DV, Levchenko V, Pavlov TS, Isaeva E, Klemens CA, Johnson J, Liu P, Kriegel AJ, Staruschenko A. Salt-deficient diet exacerbates cystogenesis in ARPKD via epithelial sodium channel (ENaC). EBioMedicine 2019; 40:663-674. [PMID: 30745171 PMCID: PMC6413684 DOI: 10.1016/j.ebiom.2019.01.006] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2018] [Revised: 01/04/2019] [Accepted: 01/05/2019] [Indexed: 12/14/2022] Open
Abstract
Background Autosomal Recessive Polycystic Kidney Disease (ARPKD) is marked by cyst formation in the renal tubules, primarily in the collecting duct (CD) system, ultimately leading to end-stage renal disease. Patients with PKD are generally advised to restrict their dietary sodium intake. This study was aimed at testing the outcomes of dietary salt manipulation in ARPKD. Methods PCK/CrljCrlPkhd1pck/CRL (PCK) rats, a model of ARPKD, were fed a normal (0.4% NaCl; NS), high salt (4% NaCl; HS), and sodium-deficient (0.01% NaCl; SD) diets for 8 weeks. Immunohistochemistry, GFR measurements, balance studies, and molecular biology approaches were applied to evaluate the outcomes of the protocol. Renin-angiotensin-aldosterone system (RAAS) levels were assessed using LC-MS/MS, and renal miRNA profiles were studied. Findings Both HS and SD diets resulted in an increase in cystogenesis. However, SD diet caused extensive growth of cysts in the renal cortical area, and hypertrophy of the tissue; RAAS components were enhanced in the SD group. We observed a reduction in epithelial Na+ channel (ENaC) expression in the SD group, accompanied with mRNA level increase. miRNA assay revealed that renal miR-9a-5p level was augmented in the SD group; we showed that this miRNA decreases ENaC channel number in CD cells. Interpretation Our data demonstrate a mechanism of ARPKD progression during salt restriction that involves activity of ENaC. We further show that miR-9a-5p potentially implicated in this mechanism and that miR-9a-5p downregulates ENaC in cultured CD cells. Our findings open new therapeutic possibilities and highlight the importance of understanding salt reabsorption in ARPKD.
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Affiliation(s)
- Daria V Ilatovskaya
- Department of Physiology, Medical College of Wisconsin, 8701 Watertown Plank Road, Milwaukee, WI 53226, USA
| | - Vladislav Levchenko
- Department of Physiology, Medical College of Wisconsin, 8701 Watertown Plank Road, Milwaukee, WI 53226, USA
| | - Tengis S Pavlov
- Department of Physiology, Medical College of Wisconsin, 8701 Watertown Plank Road, Milwaukee, WI 53226, USA
| | - Elena Isaeva
- Department of Physiology, Medical College of Wisconsin, 8701 Watertown Plank Road, Milwaukee, WI 53226, USA
| | - Christine A Klemens
- Department of Physiology, Medical College of Wisconsin, 8701 Watertown Plank Road, Milwaukee, WI 53226, USA
| | - Jessica Johnson
- Department of Physiology, Medical College of Wisconsin, 8701 Watertown Plank Road, Milwaukee, WI 53226, USA
| | - Pengyuan Liu
- Department of Physiology, Medical College of Wisconsin, 8701 Watertown Plank Road, Milwaukee, WI 53226, USA
| | - Alison J Kriegel
- Department of Physiology, Medical College of Wisconsin, 8701 Watertown Plank Road, Milwaukee, WI 53226, USA
| | - Alexander Staruschenko
- Department of Physiology, Medical College of Wisconsin, 8701 Watertown Plank Road, Milwaukee, WI 53226, USA; Clement J. Zablocki VA Medical Center, 5000 West National Avenue, Milwaukee, WI, 53295, USA.
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18
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Malekshahabi T, Khoshdel Rad N, Serra AL, Moghadasali R. Autosomal dominant polycystic kidney disease: Disrupted pathways and potential therapeutic interventions. J Cell Physiol 2019; 234:12451-12470. [PMID: 30644092 DOI: 10.1002/jcp.28094] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2018] [Accepted: 12/07/2018] [Indexed: 12/18/2022]
Abstract
Autosomal dominant polycystic kidney disease (ADPKD) is a monogenic inherited renal cystic disease that occurs in different races worldwide. It is characterized by the development of a multitude of renal cysts, which leads to massive enlargement of the kidney and often to renal failure in adulthood. ADPKD is caused by a mutation in PKD1 or PKD2 genes encoding the proteins polycystin-1 and polycystin-2, respectively. Recent studies showed that cyst formation and growth result from deregulation of multiple cellular pathways like proliferation, apoptosis, metabolic processes, cell polarity, and immune defense. In ADPKD, intracellular cyclic adenosine monophosphate (cAMP) promotes cyst enlargement by stimulating cell proliferation and transepithelial fluid secretion. Several interventions affecting many of these defective signaling pathways have been effective in animal models and some are currently being tested in clinical trials. Moreover, the stem cell therapy can improve nephropathies and according to studies were done in this field, can be considered as a hopeful therapeutic approach in future for PKD. This study provides an in-depth review of the relevant molecular pathways associated with the pathogenesis of ADPKD and their implications in development of potential therapeutic strategies.
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Affiliation(s)
- Talieh Malekshahabi
- Department of Stem Cells and Developmental Biology, Cell Science Research Center, Royan Institute for Stem Cell Biology and Technology, ACECR, Tehran, Iran
| | - Niloofar Khoshdel Rad
- Department of Stem Cells and Developmental Biology, Cell Science Research Center, Royan Institute for Stem Cell Biology and Technology, ACECR, Tehran, Iran
| | - Andreas L Serra
- Department of Internal Medicine and Nephrology, Klinik Hirslanden, Zurich, Switzerland
| | - Reza Moghadasali
- Department of Stem Cells and Developmental Biology, Cell Science Research Center, Royan Institute for Stem Cell Biology and Technology, ACECR, Tehran, Iran
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19
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Bissler JJ, Zadjali F, Bridges D, Astrinidis A, Barone S, Yao Y, Redd JR, Siroky BJ, Wang Y, Finley JT, Rusiniak ME, Baumann H, Zahedi K, Gross KW, Soleimani M. Tuberous sclerosis complex exhibits a new renal cystogenic mechanism. Physiol Rep 2019; 7:e13983. [PMID: 30675765 PMCID: PMC6344348 DOI: 10.14814/phy2.13983] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2018] [Accepted: 12/20/2018] [Indexed: 02/06/2023] Open
Abstract
Tuberous sclerosis complex (TSC) is a tumor predisposition syndrome with significant renal cystic and solid tumor disease. While the most common renal tumor in TSC, the angiomyolipoma, exhibits a loss of heterozygosity associated with disease, we have discovered that the renal cystic epithelium is composed of type A intercalated cells that have an intact Tsc gene that have been induced to exhibit Tsc-mutant disease phenotype. This mechanism appears to be different than that for ADPKD. The murine models described here closely resemble the human disease and both appear to be mTORC1 inhibitor responsive. The induction signaling driving cystogenesis may be mediated by extracellular vesicle trafficking.
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Affiliation(s)
- John J. Bissler
- Department of PediatricsUniversity of Tennessee Health Science Center and Le Bonheur Children's HospitalMemphisTennessee
- St. Jude Children's Research HospitalMemphisTennessee
| | - Fahad Zadjali
- Department of Clinical BiochemistryCollege of Medicine & Health SciencesSultan Qaboos UniversityMuscatOman
| | - Dave Bridges
- Department of Nutritional SciencesUniversity of Michigan School of Public HealthAnn ArborMichigan
| | - Aristotelis Astrinidis
- Department of PediatricsUniversity of Tennessee Health Science Center and Le Bonheur Children's HospitalMemphisTennessee
| | - Sharon Barone
- Departments of MedicineUniversity of Cincinnati College of MedicineCincinnatiOhio
- Center on Genetics of TransportUniversity of Cincinnati College of MedicineCincinnatiOhio
- Research ServicesVeterans Affairs Medical CenterCincinnatiOhio
| | - Ying Yao
- Department of PediatricsUniversity of Tennessee Health Science Center and Le Bonheur Children's HospitalMemphisTennessee
| | - JeAnna R. Redd
- Department of Nutritional SciencesUniversity of Michigan School of Public HealthAnn ArborMichigan
| | - Brian J. Siroky
- Department of PediatricsUniversity of Cincinnati College of MedicineCincinnatiOhio
| | - Yanqing Wang
- Department of Molecular and Cellular BiologyRoswell Park Cancer InstituteBuffaloNew York
| | - Joel T. Finley
- Department of PediatricsUniversity of Tennessee Health Science Center and Le Bonheur Children's HospitalMemphisTennessee
| | - Michael E. Rusiniak
- Department of Molecular and Cellular BiologyRoswell Park Cancer InstituteBuffaloNew York
| | - Heinz Baumann
- Department of Molecular and Cellular BiologyRoswell Park Cancer InstituteBuffaloNew York
| | - Kamyar Zahedi
- Departments of MedicineUniversity of Cincinnati College of MedicineCincinnatiOhio
- Center on Genetics of TransportUniversity of Cincinnati College of MedicineCincinnatiOhio
- Research ServicesVeterans Affairs Medical CenterCincinnatiOhio
| | - Kenneth W. Gross
- Department of Molecular and Cellular BiologyRoswell Park Cancer InstituteBuffaloNew York
| | - Manoocher Soleimani
- Departments of MedicineUniversity of Cincinnati College of MedicineCincinnatiOhio
- Center on Genetics of TransportUniversity of Cincinnati College of MedicineCincinnatiOhio
- Research ServicesVeterans Affairs Medical CenterCincinnatiOhio
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20
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Teulon J, Planelles G, Sepúlveda FV, Andrini O, Lourdel S, Paulais M. Renal Chloride Channels in Relation to Sodium Chloride Transport. Compr Physiol 2018; 9:301-342. [DOI: 10.1002/cphy.c180024] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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21
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Noitem R, Yuajit C, Soodvilai S, Muanprasat C, Chatsudthipong V. Steviol slows renal cyst growth by reducing AQP2 expression and promoting AQP2 degradation. Biomed Pharmacother 2018. [PMID: 29524884 DOI: 10.1016/j.biopha.2018.02.139] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022] Open
Abstract
Overexpression of aquaporin 2 (AQP2) was observed and suggested to be involved in fluid secretion leading to cyst enlargement in polycystic kidney disease (PKD). The cyst expansion deteriorates the renal function and, therefore, therapies targeting cyst enlargement are of clinical interest. Of note, inhibition of vasopressin function using vasopressin 2 receptor (V2R) antagonist which decreased cAMP production along with AQP2 production and function can slow cyst growth in ADPKD. This finding supports the role of AQP2 in cyst enlargement. Steviol, a major metabolite of the sweetening compound stevioside, was reported to retard MDCK cyst growth and enlargement by inhibiting CFTR activity. Interestingly, its efficacy was found to be higher than that of CFTRinh-172. Since steviol was also found to produce diuresis in rodent, it is likely that steviol might have an additional effect in retarding cyst progression, such as inhibition of AQP2 expression and function. Here, we investigated the effect of steviol on AQP2 function and on cyst growth using an in vitro cyst model (MDCK and Pkd1-/- cells). We found that steviol could markedly inhibit cyst growth by reducing AQP2 expression in both Pkd1-/- and MDCK cells. Real-time PCR also revealed that steviol decreased AQP2 mRNA expression level as well. Moreover, a proteasome inhibitor, MG-132, and the lysosomotropic agent, hydroxychloroquine (HCQ) were found to abolish the inhibitory effect of steviol in Pkd1-/- cells. Increased lysosomal enzyme marker (LAMP2) expression following steviol treatment clearly confirmed the involvement of lysosomes in steviol action. In conclusion, our finding showed for the first time that steviol slowed cyst growth, in part, by reducing AQP2 transcription, promoted proteasome, and lysosome-mediated AQP2 degradation. Due to its multiple actions, steviol is a promising compound for further development in the treatment of PKD.
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Affiliation(s)
- Rattikarn Noitem
- Department of Physiology, Faculty of Science, Mahidol University, Ratchathewi, Bangkok, Thailand
| | - Chaowalit Yuajit
- College of Medicine and Public Health, Ubon Ratchathani University, Warin Chamrap, Ubon Ratchathani, Thailand
| | - Sunhapas Soodvilai
- Department of Physiology, Faculty of Science, Mahidol University, Ratchathewi, Bangkok, Thailand
| | - Chatchai Muanprasat
- Department of Physiology, Faculty of Science, Mahidol University, Ratchathewi, Bangkok, Thailand; Excellent Center for Drug Discovery, Mahidol University, Ratchathewi, Bangkok, Thailand; Translational Medicine Graduate Program, Faculty of Medicine Ramathibodi Hospital, Mahidol University, Ratchathewi, Bangkok, Thailand
| | - Varanuj Chatsudthipong
- Department of Physiology, Faculty of Science, Mahidol University, Ratchathewi, Bangkok, Thailand.
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22
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Nag S, Resnick A. Stabilization of hypoxia inducible factor by cobalt chloride can alter renal epithelial transport. Physiol Rep 2017; 5:5/24/e13531. [PMID: 29263117 PMCID: PMC5742700 DOI: 10.14814/phy2.13531] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2017] [Revised: 10/27/2017] [Accepted: 10/31/2017] [Indexed: 01/10/2023] Open
Abstract
Given the importance of the transcriptional regulator hypoxia-inducible factor-1 (HIF-1) for adaptive hypoxia responses, we examined the effect of stabilized HIF-1α on renal epithelial permeability and directed sodium transport. This study was motivated by histological analysis of cystic kidneys showing increased expression levels of HIF-1α and HIF-2α We hypothesize that compression induced localized ischemia-hypoxia of normal epithelia near a cyst leads to local stabilization of HIF-1α, leading to altered transepithelial transport that encourages cyst expansion. We found that stabilized HIF-1α alters both transcellular and paracellular transport through renal epithelial monolayers in a manner consistent with secretory behavior, indicating localized ischemia-hypoxia may lead to altered salt and water transport through kidney epithelial monolayers. A quantity of 100 μmol/L Cobalt chloride (CoCl2) was used acutely to stabilize HIF-1α in confluent cultures of mouse renal epithelia. We measured increased transepithelial permeability and decreased transepithelial resistance (TER) when HIF-1α was stabilized. Most interestingly, we measured a change in the direction of sodium current, most likely corresponding to abnormal secretory function, supporting our positive-feedback hypothesis.
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Affiliation(s)
- Subhra Nag
- Department of Biology, Geology and Environmental Sciences, Cleveland State University, Cleveland, Ohio
| | - Andrew Resnick
- Department of Biology, Geology and Environmental Sciences, Cleveland State University, Cleveland, Ohio .,Department of Physics Cleveland State University, Cleveland, Ohio.,Center for Gene Regulation in Health and Disease, Cleveland State University, Cleveland, Ohio
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23
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Mechanical Characterization of Microengineered Epithelial Cysts by Using Atomic Force Microscopy. Biophys J 2017; 112:398-409. [PMID: 28122225 DOI: 10.1016/j.bpj.2016.12.026] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2016] [Revised: 11/16/2016] [Accepted: 12/19/2016] [Indexed: 01/01/2023] Open
Abstract
Most organs contain interconnected tubular tissues that are one-cell-thick, polarized epithelial monolayers enclosing a fluid-filled lumen. Such tissue organization plays crucial roles in developmental and normal physiology, and the proper functioning of these tissues depends on their regulation by complex biochemical perturbations and equally important, but poorly understood, mechanical perturbations. In this study, by combining micropatterning techniques and atomic force microscopy, we developed a simple in vitro experimental platform for characterizing the mechanical properties of the MDCK II cyst, the simplest model of lumen-enclosing epithelial monolayers. By using this platform, we estimated the elasticity of the cyst monolayer and showed that the presence of a luminal space influences cyst mechanics substantially, which could be attributed to polarization and tissue-level coordination. More interestingly, the results from force-relaxation experiments showed that the cysts also displayed tissue-level poroelastic characteristics that differed slightly from those of single cells. Our study provides the first quantitative findings, to our knowledge, on the tissue-level mechanics of well-polarized epithelial cysts and offers new insights into the interplay between cyst mechanics and cyst physiology. Moreover, our simple platform is a potentially useful tool for enhancing the current understanding of cyst mechanics in health and disease.
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Balasubramaniam SL, Gopalakrishnapillai A, Petrelli NJ, Barwe SP. Knockdown of sodium-calcium exchanger 1 induces epithelial-to-mesenchymal transition in kidney epithelial cells. J Biol Chem 2017; 292:11388-11399. [PMID: 28550085 DOI: 10.1074/jbc.m116.752352] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2016] [Revised: 05/17/2017] [Indexed: 12/17/2022] Open
Abstract
Mesenchymal-to-epithelial transition (MET) and epithelial-to-mesenchymal transition (EMT) are important processes in kidney development. Failure to undergo MET during development leads to the initiation of Wilms tumor, whereas EMT contributes to the development of renal cell carcinomas (RCC). The role of calcium regulators in governing these processes is becoming evident. We demonstrated earlier that Na+/Ca2+ exchanger 1 (NCX1), a major calcium exporter in renal epithelial cells, regulates epithelial cell motility. Here, we show for the first time that NCX1 mRNA and protein expression was down-regulated in Wilms tumor and RCC. Knockdown of NCX1 in Madin-Darby canine kidney cells induced fibroblastic morphology, increased intercellular junctional distance, and induced paracellular permeability, loss of apico-basal polarity in 3D cultures, and anchorage-independent growth, accompanied by expression of mesenchymal markers. We also provide evidence that NCX1 interacts with and anchors E-cadherin to the cell surface independent of NCX1 ion transport activity. Consistent with destabilization of E-cadherin, NCX1 knockdown cells showed an increase in β-catenin nuclear localization, enhanced transcriptional activity, and up-regulation of downstream targets of the β-catenin signaling pathway. Taken together, knockdown of NCX1 in Madin-Darby canine kidney cells alters epithelial morphology and characteristics by destabilization of E-cadherin and induction of β-catenin signaling.
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Affiliation(s)
- Sona Lakshme Balasubramaniam
- From the Nemours Center for Childhood Cancer Research, Alfred I. duPont Hospital for Children, Wilmington, Delaware 19803.,the Department of Biological Sciences, University of Delaware, Newark, Delaware 19716, and
| | - Anilkumar Gopalakrishnapillai
- From the Nemours Center for Childhood Cancer Research, Alfred I. duPont Hospital for Children, Wilmington, Delaware 19803
| | - Nicholas J Petrelli
- the Helen F. Graham Cancer Center, Christiana Care Health System, Newark, Delaware 19718
| | - Sonali P Barwe
- From the Nemours Center for Childhood Cancer Research, Alfred I. duPont Hospital for Children, Wilmington, Delaware 19803, .,the Department of Biological Sciences, University of Delaware, Newark, Delaware 19716, and
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25
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Ilatovskaya DV, Palygin O, Staruschenko A. Functional and therapeutic importance of purinergic signaling in polycystic kidney disease. Am J Physiol Renal Physiol 2016; 311:F1135-F1139. [PMID: 27654892 DOI: 10.1152/ajprenal.00406.2016] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2016] [Accepted: 09/20/2016] [Indexed: 12/12/2022] Open
Abstract
Polycystic kidney diseases (PKD) are a group of inherited nephropathies marked with the formation of fluid-filled cysts along the nephron. This renal disorder affects millions of people worldwide, but current treatment strategies are unfortunately limited to supportive therapy, dietary restrictions, and, eventually, renal transplantation. Recent advances in PKD management are aimed at targeting exaggerated cell proliferation and dedifferentiation to interfere with cyst growth. However, not nearly enough is known about the ion transport properties of the cystic cells, or specific signaling pathways modulating channels and transporters in this condition. There is growing evidence that abnormally elevated concentrations of adenosine triphosphate (ATP) in PKD may contribute to cyst enlargement; change in the profile of purinergic receptors may also result in promotion of cystogenesis. The current mini-review is focused on the role of ATP and associated signaling affecting ion transport properties of the renal cystic epithelia.
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Affiliation(s)
- Daria V Ilatovskaya
- Department of Physiology, Medical College of Wisconsin, Milwaukee, Wisconsin
| | - Oleg Palygin
- Department of Physiology, Medical College of Wisconsin, Milwaukee, Wisconsin
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26
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Gentile G, Remuzzi G. Novel Biomarkers for Renal Diseases? None for the Moment (but One). SLAS DISCOVERY 2016; 21:655-670. [DOI: 10.1177/1087057116629916] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/30/2023]
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27
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Wu M, Yu S. New Insights into the Molecular Mechanisms Targeting Tubular Channels/Transporters in PKD Development. KIDNEY DISEASES 2016; 2:128-135. [PMID: 27921040 DOI: 10.1159/000444839] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/05/2016] [Accepted: 02/18/2016] [Indexed: 12/15/2022]
Abstract
BACKGROUND Autosomal dominant polycystic kidney disease (PKD) or autosomal recessive PKD is caused by a mutation in the PKD1, PKD2 or PKHD1 gene, which encodes polycystin-1, polycystin-2 or fibrocystin, respectively. Embryonic and postnatal mutation studies show that transport or channel function is dysregulated before the initiation of cystogenesis, suggesting that the abnormality of transport or channel function plays a critical role in the pathology of PKD. SUMMARY Polycystin-2 by itself is a calcium-permeable cation channel, and its channel function can be regulated by polycystin-1 or fibrocystin. In this paper, we reviewed the current knowledge about calcium transports and cyclic adenosine monophosphate (cAMP)-driven chloride transports in PKD. In addition, the function and the underlining mechanism of glucose transporters, phosphate transporters and water channels in PKD are also discussed. KEY MESSAGES Abnormalities in calcium handling and exuberant cAMP-dependent cystic fibrosis transmembrane conductance regulator-mediated fluid secretion in the collecting duct are the most important issues in the pathogenesis of PKD.
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Affiliation(s)
- Ming Wu
- Kidney Institute of PLA, Division of Nephrology, Shanghai Changzheng Hospital, Second Military Medical University, Shanghai, PR China
| | - Shengqiang Yu
- Kidney Institute of PLA, Division of Nephrology, Shanghai Changzheng Hospital, Second Military Medical University, Shanghai, PR China
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28
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Jansson K, Venugopal J, Sánchez G, Magenheimer BS, Reif GA, Wallace DP, Calvet JP, Blanco G. Ouabain Regulates CFTR-Mediated Anion Secretion and Na,K-ATPase Transport in ADPKD Cells. J Membr Biol 2015; 248:1145-57. [PMID: 26289599 DOI: 10.1007/s00232-015-9832-7] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2015] [Accepted: 08/06/2015] [Indexed: 01/16/2023]
Abstract
Cyst enlargement in autosomal dominant polycystic kidney disease (ADPKD) requires the transepithelial secretion of fluid into the cyst lumen. We previously showed that physiological amounts of ouabain enhance cAMP-dependent fluid secretion and cyst growth of human ADPKD cyst epithelial cells in culture and formation of cyst-like dilations in metanephric kidneys from Pkd1 mutant mice. Here, we investigated the mechanisms by which ouabain promotes cAMP-dependent fluid secretion and cystogenesis. Ouabain (3 nM) enhanced cAMP-induced cyst-like dilations in embryonic kidneys from Pkd1 (m1Bei) mice, but had no effect on metanephroi from Pkd1 (m1Bei) mice that lack expression of the cystic fibrosis transmembrane conductance regulator (CFTR). Similarly, ouabain stimulation of cAMP-induced fluid secretion and in vitro cyst growth of ADPKD cells were abrogated by CFTR inhibition, showing that CFTR is required for ouabain effects on ADPKD fluid secretion. Moreover, ouabain directly enhanced the cAMP-dependent Cl(-) efflux mediated by CFTR in ADPKD monolayers. Ouabain increased the trafficking of CFTR to the plasma membrane and up-regulated the expression of the CFTR activator PDZK1. Finally, ouabain decreased plasma membrane expression and activity of the Na,K-ATPase in ADPKD cells. Altogether, these results show that ouabain enhances net fluid secretion and cyst formation by activating apical anion secretion via CFTR and decreasing basolateral Na(+) transport via Na,K-ATPase. These results provide new information on the mechanisms by which ouabain affects ADPKD cells and further highlight the importance of ouabain as a non-genomic stimulator of cystogenesis in ADPKD.
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Affiliation(s)
- Kyle Jansson
- Department of Molecular and Integrative Physiology, University of Kansas Medical Center, 3901 Rainbow Boulevard, Kansas City, KS, 66160, USA.,The Kidney Institute, University of Kansas Medical Center, Kansas City, KS, USA
| | - Jessica Venugopal
- Department of Molecular and Integrative Physiology, University of Kansas Medical Center, 3901 Rainbow Boulevard, Kansas City, KS, 66160, USA.,The Kidney Institute, University of Kansas Medical Center, Kansas City, KS, USA
| | - Gladis Sánchez
- Department of Molecular and Integrative Physiology, University of Kansas Medical Center, 3901 Rainbow Boulevard, Kansas City, KS, 66160, USA.,The Kidney Institute, University of Kansas Medical Center, Kansas City, KS, USA
| | - Brenda S Magenheimer
- Department of Biochemistry and Molecular Biology, University of Kansas Medical Center, Kansas City, KS, USA.,The Kidney Institute, University of Kansas Medical Center, Kansas City, KS, USA
| | - Gail A Reif
- Department of Medicine, University of Kansas Medical Center, Kansas City, KS, USA.,The Kidney Institute, University of Kansas Medical Center, Kansas City, KS, USA
| | - Darren P Wallace
- Department of Molecular and Integrative Physiology, University of Kansas Medical Center, 3901 Rainbow Boulevard, Kansas City, KS, 66160, USA.,Department of Medicine, University of Kansas Medical Center, Kansas City, KS, USA.,The Kidney Institute, University of Kansas Medical Center, Kansas City, KS, USA
| | - James P Calvet
- Department of Biochemistry and Molecular Biology, University of Kansas Medical Center, Kansas City, KS, USA.,The Kidney Institute, University of Kansas Medical Center, Kansas City, KS, USA
| | - Gustavo Blanco
- Department of Molecular and Integrative Physiology, University of Kansas Medical Center, 3901 Rainbow Boulevard, Kansas City, KS, 66160, USA. .,The Kidney Institute, University of Kansas Medical Center, Kansas City, KS, USA.
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29
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Chebib FT, Sussman CR, Wang X, Harris PC, Torres VE. Vasopressin and disruption of calcium signalling in polycystic kidney disease. Nat Rev Nephrol 2015; 11:451-64. [PMID: 25870007 PMCID: PMC4539141 DOI: 10.1038/nrneph.2015.39] [Citation(s) in RCA: 87] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Autosomal dominant polycystic kidney disease (ADPKD) is the most common monogenic kidney disease and is responsible for 5-10% of cases of end-stage renal disease worldwide. ADPKD is characterized by the relentless development and growth of cysts, which cause progressive kidney enlargement associated with hypertension, pain, reduced quality of life and eventual kidney failure. Mutations in the PKD1 or PKD2 genes, which encode polycystin-1 (PC1) and polycystin-2 (PC2), respectively, cause ADPKD. However, neither the functions of these proteins nor the molecular mechanisms of ADPKD pathogenesis are well understood. Here, we review the literature that examines how reduced levels of functional PC1 or PC2 at the primary cilia and/or the endoplasmic reticulum directly disrupts intracellular calcium signalling and indirectly disrupts calcium-regulated cAMP and purinergic signalling. We propose a hypothetical model in which dysregulated metabolism of cAMP and purinergic signalling increases the sensitivity of principal cells in collecting ducts and of tubular epithelial cells in the distal nephron to the constant tonic action of vasopressin. The resulting magnified response to vasopressin further enhances the disruption of calcium signalling that is initiated by mutations in PC1 or PC2, and activates downstream signalling pathways that cause impaired tubulogenesis, increased cell proliferation, increased fluid secretion and interstitial inflammation.
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Affiliation(s)
- Fouad T Chebib
- Division of Nephrology and Hypertension, 200 First Street S. W., Mayo Clinic College of Medicine, Rochester, MN 55901, USA
| | - Caroline R Sussman
- Division of Nephrology and Hypertension, 200 First Street S. W., Mayo Clinic College of Medicine, Rochester, MN 55901, USA
| | - Xiaofang Wang
- Division of Nephrology and Hypertension, 200 First Street S. W., Mayo Clinic College of Medicine, Rochester, MN 55901, USA
| | - Peter C Harris
- Division of Nephrology and Hypertension, 200 First Street S. W., Mayo Clinic College of Medicine, Rochester, MN 55901, USA
| | - Vicente E Torres
- Division of Nephrology and Hypertension, 200 First Street S. W., Mayo Clinic College of Medicine, Rochester, MN 55901, USA
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30
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Huqi San-Evoked Rat Colonic Anion Secretion through Increasing CFTR Expression. EVIDENCE-BASED COMPLEMENTARY AND ALTERNATIVE MEDICINE 2015; 2015:301640. [PMID: 26290673 PMCID: PMC4531196 DOI: 10.1155/2015/301640] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/13/2014] [Revised: 10/06/2014] [Accepted: 10/12/2014] [Indexed: 02/07/2023]
Abstract
Huqi San (HQS) is a Chinese herbal preparation of eight medicinal herbs that promote diuresis, detoxification, blood circulation, and cholestasis. Defects in transporter expression and function can cause cholestasis and jaundice. However, the mechanism of the cholestasis underlying HQS effects, especially on the gastrointestinal tract ion secretion, has not been elucidated. Real-time RT-PCR and Western blotting were used to study the expression and localization of cystic fibrosis transmembrane conductance regulator (CFTR) and α-ENaC in rat alimentary tract, and then the effect of HQS on the ion transport in rat distal colon mucosa was investigated using the short-circuit current (ISC) technique. The results showed that pretreatment with HQS significantly enhanced mRNA transcripts and protein content of CFTR in liver and distal colon but not α-ENaC in alimentary organs. HQS increases ISC and decreases the transepithelial resistance. Pretreatment with epithelial Na+ channel blocker did not affect the ISC responses elicited by HQS, but removal of extracellular Cl− or pretreatment with Cl− channel or Na+-K+-2Cl− cotransporter blocker inhibited HQS-elicited ISC responses. These findings demonstrated that HQS, RA, and RP can stimulate Cl− secretion in the distal colon by increasing the mRNA transcripts and protein content of CFTR in liver and distal colon.
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31
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Cui G, McCarty NA. Murine and human CFTR exhibit different sensitivities to CFTR potentiators. Am J Physiol Lung Cell Mol Physiol 2015. [PMID: 26209275 DOI: 10.1152/ajplung.00181.2015] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Development of therapeutic molecules with clinical efficacy as modulators of defective CFTR includes efforts to identify potentiators that can overcome or repair the gating defect in mutant CFTR channels. This has taken a great leap forward with the identification of the potentiator VX-770, now available to patients as "Kalydeco." Other small molecules with different chemical structure also are capable of potentiating the activity of either wild-type or mutant CFTR, suggesting that there are features of the protein that may be targeted to achieve stimulation of channel activity by structurally diverse compounds. However, neither the mechanisms by which these compounds potentiate mutant CFTR nor the site(s) where these compounds bind have been identified. This knowledge gap partly reflects the lack of appropriate experimental models to provide clues toward the identification of binding sites. Here, we have compared the channel behavior and response to novel and known potentiators of human CFTR (hCFTR) and murine (mCFTR) expressed in Xenopus oocytes. Both hCFTR and mCFTR were blocked by GlyH-101 from the extracellular side, but mCFTR activity was increased with GlyH-101 applied directly to the cytoplasmic side. Similarly, glibenclamide only exhibited a blocking effect on hCFTR but both blocked and potentiated mCFTR in excised membrane patches and in intact oocytes. The clinically used CFTR potentiator VX-770 transiently increased hCFTR by ∼13% but potentiated mCFTR significantly more strongly. Our results suggest that mCFTR pharmacological sensitivities differ from hCFTR, which will provide a useful tool for identifying the binding sites and mechanism for these potentiators.
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Affiliation(s)
- Guiying Cui
- Division of Pulmonology, Allergy/Immunology, Cystic Fibrosis, and Sleep, Department of Pediatrics, Emory + Children's Center for Cystic Fibrosis and Airways Disease Research, Emory University School of Medicine and Children's Healthcare of Atlanta, Atlanta, Georgia
| | - Nael A McCarty
- Division of Pulmonology, Allergy/Immunology, Cystic Fibrosis, and Sleep, Department of Pediatrics, Emory + Children's Center for Cystic Fibrosis and Airways Disease Research, Emory University School of Medicine and Children's Healthcare of Atlanta, Atlanta, Georgia
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32
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Noël N, Rieu P. [Pathophysiology, epidemiology, clinical presentation, diagnosis and treatment options for autosomal dominant polycystic kidney disease]. Nephrol Ther 2015; 11:213-25. [PMID: 26113401 DOI: 10.1016/j.nephro.2015.04.001] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2014] [Revised: 04/07/2015] [Accepted: 04/08/2015] [Indexed: 01/12/2023]
Abstract
Autosomal dominant polycystic kidney disease (ADPKD) is the leading genetic cause of end-stage renal disease (ESRD) worldwide. Its prevalence is evaluated according to studies and population between 1/1000 and 1/4000 live births and it accounts for 6 to 8% of incident ESRD patients in developed countries. ADPKD is characterized by numerous cysts in both kidneys and various extrarenal manifestations that are detailed in this review. Clinico-radiological and genetic diagnosis are also discussed. Mutations in the PKD1 and PKD2 codifying for polycystin-1 (PC-1) and polycystin-2 (PC-2) are responsible for the 85 and 15% of ADPKD cases, respectively. In primary cilia of normal kidney epithelial cells, PC-1 and PC-2 interact forming a complex involved in flow- and cilia-dependant signalling pathways where intracellular calcium and cAMP play a central role. Alteration of these multiple signal transduction pathways leads to cystogenesis accompanied by dysregulated planar cell polarity, excessive cell proliferation and fluid secretion, and pathogenic interactions of epithelial cells with an abnormal extracellular matrix. The mass effect of expanding cyst is responsible for the decline in glomerular filtration rate that occurs late in the course of the disease. For many decades, the treatment for ADPKD aims to lessen the condition's symptoms, limit kidney damage, and prevent complications. Recently, the development of promising specific treatment raises the hope to slow the growth of cysts and delay the disease. Treatment strategies targeting cAMP signalling such as vasopressin receptor antagonists or somatostatin analogs have been tested successfully in clinical trials with relative safety. Newer treatments supported by preclinical trials will become available in the next future. Recognizing early markers of renal progression (clinical, imaging, and genetic markers) to identify high-risk patients and multidrug approaches with synergistic effects may provide new opportunities for the treatment of ADPKD.
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Affiliation(s)
- Natacha Noël
- Service de néphrologie, centre hospitalier universitaire de Reims, 51100 Reims, France
| | - Philippe Rieu
- Service de néphrologie, centre hospitalier universitaire de Reims, 51100 Reims, France.
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33
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LaRiviere WB, Irazabal MV, Torres VE. Novel therapeutic approaches to autosomal dominant polycystic kidney disease. Transl Res 2015; 165:488-98. [PMID: 25438190 PMCID: PMC4363282 DOI: 10.1016/j.trsl.2014.11.003] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/11/2014] [Revised: 10/17/2014] [Accepted: 11/06/2014] [Indexed: 01/14/2023]
Abstract
Autosomal dominant polycystic kidney disease (ADPKD) is an inherited disorder characterized by the progressive growth of renal cysts that, over time, destroy the architecture of the renal parenchyma and typically lead to kidney failure by the sixth decade of life. ADPKD is common and represents a leading cause of renal failure worldwide. Currently, there are no Food and Drug Administration-approved treatments for the disease, and the existing standard of care is primarily supportive in nature. However, significant advances in the understanding of the molecular biology of the disease have inspired investigation into potential new therapies. Several drugs designed to slow or arrest the progression of ADPKD have shown promise in preclinical models and clinical trials, including vasopressin receptor antagonists and somatostatin analogs. This article examines the literature underlying the rationale for molecular therapies for ADPKD and reviews the existing clinical evidence for their indication for human patients with the disease.
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Affiliation(s)
- Wells B LaRiviere
- Division of Nephrology and Hypertension, Mayo Clinic, Rochester, Minn
| | - Maria V Irazabal
- Division of Nephrology and Hypertension, Mayo Clinic, Rochester, Minn
| | - Vicente E Torres
- Division of Nephrology and Hypertension, Mayo Clinic, Rochester, Minn.
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34
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Intermediate conductance, Ca2+-activated K+ channels: a novel target for chronic renal diseases. ACTA ACUST UNITED AC 2014. [DOI: 10.1007/s11515-014-1339-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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35
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Cui G, Rahman KS, Infield DT, Kuang C, Prince CZ, McCarty NA. Three charged amino acids in extracellular loop 1 are involved in maintaining the outer pore architecture of CFTR. ACTA ACUST UNITED AC 2014; 144:159-79. [PMID: 25024266 PMCID: PMC4113900 DOI: 10.1085/jgp.201311122] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Disease-associated mutation of charged amino acids in extracellular loop 1 of CFTR may reduce chloride flow by damaging the outer pore architecture. The cystic fibrosis (CF) transmembrane conductance regulator (CFTR) bears six extracellular loops (ECL1–6); ECL1 is the site of several mutations associated with CF. Mutation R117H has been reported to reduce current amplitude, whereas D110H, E116K, and R117C/L/P may impair channel stability. We hypothesized that these amino acids might not be directly involved in ion conduction and permeation but may contribute to stabilizing the outer vestibule architecture in CFTR. We used cRNA injected oocytes combined with electrophysiological techniques to test this hypothesis. Mutants bearing cysteine at these sites were not functionally modified by extracellular MTS reagents and were blocked by GlyH-101 similarly to WT-CFTR. These results suggest that these three residues do not contribute directly to permeation in CFTR. In contrast, mutants D110R-, E116R-, and R117A-CFTR exhibited instability of the open state and significantly shortened burst duration compared with WT-CFTR and failed to be locked into the open state by AMP-PNP (adenosine 5′-(β,γ-imido) triphosphate); charge-retaining mutants showed mainly the full open state with comparably longer open burst duration. These interactions suggest that these ECL1 residues might be involved in maintaining the outer pore architecture of CFTR. A CFTR homology model suggested that E116 interacts with R104 in both the closed and open states, D110 interacts with K892 in the fully closed state, and R117 interacts with E1126 in the open state. These interactions were confirmed experimentally. The results suggest that D110, E116, and R117 may contribute to stabilizing the architecture of the outer pore of CFTR by interactions with other charged residues.
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Affiliation(s)
- Guiying Cui
- Division of Pulmonary, Allergy and Immunology, Cystic Fibrosis, and Sleep, Department of Pediatrics, Center for Cystic Fibrosis and Airways Disease Research, Emory+Children's Pediatric Research Center, Emory University School of Medicine and Children's Healthcare of Atlanta, Atlanta, GA 30322
| | - Kazi S Rahman
- Parker H. Petit Institute for Bioengineering and Bioscience and School of Biology, Georgia Institute of Technology, Atlanta, GA 30332 Parker H. Petit Institute for Bioengineering and Bioscience and School of Biology, Georgia Institute of Technology, Atlanta, GA 30332
| | - Daniel T Infield
- Division of Pulmonary, Allergy and Immunology, Cystic Fibrosis, and Sleep, Department of Pediatrics, Center for Cystic Fibrosis and Airways Disease Research, Emory+Children's Pediatric Research Center, Emory University School of Medicine and Children's Healthcare of Atlanta, Atlanta, GA 30322
| | - Christopher Kuang
- Division of Pulmonary, Allergy and Immunology, Cystic Fibrosis, and Sleep, Department of Pediatrics, Center for Cystic Fibrosis and Airways Disease Research, Emory+Children's Pediatric Research Center, Emory University School of Medicine and Children's Healthcare of Atlanta, Atlanta, GA 30322
| | - Chengyu Z Prince
- Division of Pulmonary, Allergy and Immunology, Cystic Fibrosis, and Sleep, Department of Pediatrics, Center for Cystic Fibrosis and Airways Disease Research, Emory+Children's Pediatric Research Center, Emory University School of Medicine and Children's Healthcare of Atlanta, Atlanta, GA 30322
| | - Nael A McCarty
- Division of Pulmonary, Allergy and Immunology, Cystic Fibrosis, and Sleep, Department of Pediatrics, Center for Cystic Fibrosis and Airways Disease Research, Emory+Children's Pediatric Research Center, Emory University School of Medicine and Children's Healthcare of Atlanta, Atlanta, GA 30322 Parker H. Petit Institute for Bioengineering and Bioscience and School of Biology, Georgia Institute of Technology, Atlanta, GA 30332
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36
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CFTR structure and cystic fibrosis. Int J Biochem Cell Biol 2014; 52:15-25. [PMID: 24534272 DOI: 10.1016/j.biocel.2014.02.004] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2014] [Revised: 02/04/2014] [Accepted: 02/06/2014] [Indexed: 12/31/2022]
Abstract
CFTR (cystic fibrosis transmembrane conductance regulator) is a member of the ATP-binding cassette family of membrane proteins. Although almost all members of this family are transporters, CFTR functions as a channel with specificity for anions, in particular chloride and bicarbonate. In this review we look at what is known about CFTR structure and function within the context of the ATP-binding cassette family. We also review current strategies aimed at obtaining the high resolution structure of the protein.
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37
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Yuajit C, Muanprasat C, Gallagher AR, Fedeles SV, Kittayaruksakul S, Homvisasevongsa S, Somlo S, Chatsudthipong V. Steviol retards renal cyst growth through reduction of CFTR expression and inhibition of epithelial cell proliferation in a mouse model of polycystic kidney disease. Biochem Pharmacol 2014; 88:412-21. [PMID: 24518257 DOI: 10.1016/j.bcp.2014.01.038] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2013] [Revised: 01/30/2014] [Accepted: 01/31/2014] [Indexed: 01/11/2023]
Abstract
Cyst enlargement in autosomal dominant polycystic kidney disease (ADPKD) is associated with cAMP-activated proliferation of cyst-lining epithelial cells and transepithelial fluid secretion into the cyst lumen via cystic fibrosis transmembrane conductance regulator (CFTR) chloride channel leading to renal failure for which no effective treatment is currently available. We previously reported that steviol retards Madin-Darby canine kidney (MDCK) cyst enlargement by inhibiting CFTR channel activity and promoting proteasomal-mediated CFTR degradation. It is imperative to examine the effect of steviol in animal models of ADPKD. Therefore, we examined the effect of steviol on renal cyst growth in an orthologous mouse model of human ADPKD (Pkd1(flox/flox):Pkhd1-Cre). The results showed that daily treatment with both 200mg/kg BW of steviol and 1000mg/kg BW of stevioside for 14 days markedly decreased kidney weight and cystic index in these mice. However, only steviol markedly reduced blood urea nitrogen and creatinine values. Steviol also reduced cell proliferation but had no effect on cell apoptosis. In addition, steviol suppressed CFTR and mTOR/S6K expression in renal cyst-lining epithelial cells. Interestingly, steviol was found to stimulate AMP-activated protein kinase (AMPK). Our findings indicate that steviol slows cyst progression in ADPKD mouse model, in part, through the activation of AMPK which subsequently inhibits CFTR chloride channel expression and inhibits renal epithelial cell proliferation via mTOR/S6K pathway. Most importantly, steviol could markedly improve kidney function in a mouse model of ADPKD. Steviol thus has potential application for further development as a therapeutic compound for the treatment of polycystic kidney disease.
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Affiliation(s)
- Chaowalit Yuajit
- Department of Physiology, Faculty of Science, Mahidol University, Bangkok, Thailand; Department of Internal Medicine, Genetic, Yale University School of Medicine, New Haven, CT, USA
| | - Chatchai Muanprasat
- Department of Physiology, Faculty of Science, Mahidol University, Bangkok, Thailand; Research Center of Transport Protein for Medical Innovation, Faculty of Science, Mahidol University, Bangkok, Thailand
| | - Anna-Rachel Gallagher
- Department of Internal Medicine, Genetic, Yale University School of Medicine, New Haven, CT, USA
| | - Sorin V Fedeles
- Department of Internal Medicine, Genetic, Yale University School of Medicine, New Haven, CT, USA
| | | | - Sureeporn Homvisasevongsa
- Division of Physical Science, Faculty of Science and Technology, Huachiew Chalermprakiet University, Samutprakarn, Thailand
| | - Stefan Somlo
- Department of Internal Medicine, Genetic, Yale University School of Medicine, New Haven, CT, USA.
| | - Varanuj Chatsudthipong
- Department of Physiology, Faculty of Science, Mahidol University, Bangkok, Thailand; Research Center of Transport Protein for Medical Innovation, Faculty of Science, Mahidol University, Bangkok, Thailand.
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Sweeney WE, Avner ED. Pathophysiology of childhood polycystic kidney diseases: new insights into disease-specific therapy. Pediatr Res 2014; 75:148-57. [PMID: 24336431 PMCID: PMC3953890 DOI: 10.1038/pr.2013.191] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/01/2013] [Accepted: 07/11/2013] [Indexed: 12/22/2022]
Abstract
Autosomal dominant polycystic kidney disease (ADPKD) and autosomal recessive polycystic kidney disease (ARPKD) are significant causes of morbidity and mortality in children and young adults. ADPKD, with an incidence of 1:400 to 1:1,000, affects more than 13 million individuals worldwide and is a major cause of end-stage renal disease in adults. However, symptomatic disease is increasingly recognized in children. ARPKD is a dual-organ hepatorenal disease with an incidence of 1:20,000 to 1:40,000 and a heterozygote carrier rate of 1 in 70. Currently, no clinically significant disease-specific therapy exists for ADPKD or ARPKD. The genetic basis of both ADPKD and ARPKD have been identified, and delineation of the basic molecular and cellular pathophysiology has led to the discovery that abnormal ADPKD and ARPKD gene products interact to create "polycystin complexes" located at multiple sites within affected cells. The extracellular matrix and vessels produce a variety of soluble factors that affect the biology of adjacent cells in many dynamic ways. This review will focus on the molecular and cellular bases of the abnormal cystic phenotype and discuss the clinical translation of such basic data into new therapies that promise to alter the natural history of disease for children with genetic PKDs.
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Affiliation(s)
- William E. Sweeney
- Department of Pediatrics and Children’s Research Institute, Medical College of Wisconsin and Children’s Hospital Health System of Wisconsin, Milwaukee, WI
| | - Ellis D. Avner
- Department of Pediatrics and Children’s Research Institute, Medical College of Wisconsin and Children’s Hospital Health System of Wisconsin, Milwaukee, WI,Department of Physiology, Medical College of Wisconsin, Milwaukee, WI
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Torres VE, Harris PC. Strategies targeting cAMP signaling in the treatment of polycystic kidney disease. J Am Soc Nephrol 2014; 25:18-32. [PMID: 24335972 PMCID: PMC3871779 DOI: 10.1681/asn.2013040398] [Citation(s) in RCA: 184] [Impact Index Per Article: 18.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Polycystic kidney disease (PKD) is a leading cause of ESRD worldwide. In PKD, excessive cell proliferation and fluid secretion, pathogenic interactions of mutated epithelial cells with an abnormal extracellular matrix and alternatively activated interstitial macrophages, and the disruption of mechanisms controlling tubular diameter contribute to cyst formation. Studies with animal models suggest that several diverse pathophysiologic mechanisms, including dysregulation of intracellular calcium levels and cAMP signaling, mediate these cystogenic mechanisms. This article reviews the evidence implicating calcium and cAMP as central players in a network of signaling pathways underlying the pathogenesis of PKD and considers the therapeutic relevance of treatment strategies targeting cAMP signaling.
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Affiliation(s)
- Vicente E Torres
- Division of Nephrology and Hypertension, Mayo Clinic, Rochester, Minnesota
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Rangan G. Role of extracellular ATP and P2 receptor signaling in regulating renal cyst growth and interstitial inflammation in polycystic kidney disease. Front Physiol 2013; 4:218. [PMID: 23966953 PMCID: PMC3744908 DOI: 10.3389/fphys.2013.00218] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2013] [Accepted: 07/28/2013] [Indexed: 01/04/2023] Open
Abstract
Polycystic kidney diseases (PKD) are a group of inherited ciliopathies in which the formation and growth of multiple cysts derived from the distal nephron and collecting duct leads to the disruption of normal kidney architecture, chronic interstitial inflammation/fibrosis and hypertension. Kidney failure is the most life-threatening complication of PKD, and is the consequence of cyst expansion, renal interstitial disease and loss of normal kidney tissue. Over the last decade, accumulating evidence suggests that the autocrine and paracrine effects of ATP (through its receptor family P2X and P2Y), could be detrimental for the progression of PKD. (2009). In vitro, ATP-P2 signaling promotes cystic epithelial cell proliferation, chloride-driven fluid secretion and apoptosis. Furthermore, dysfunction of the polycystin signal transduction pathways promotes the secretagogue activity of extracellular ATP by activating a calcium-activated chloride channel via purinergic receptors. Finally, ATP is a danger signal and could potentially contribute to interstitial inflammation associated with PKD. These data suggest that ATP-P2 signaling worsens the progression of cyst enlargement and interstitial inflammation in PKD.
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Affiliation(s)
- Gopi Rangan
- Michael Stern Translational Laboratory for Polycystic Kidney Disease, Centre for Transplant and Renal Research, Westmead Millennium Institute, University of Sydney Sydney, NSW, Australia
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41
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Pkd1 is required for male reproductive tract development. Mech Dev 2013; 130:567-76. [PMID: 23933588 DOI: 10.1016/j.mod.2013.07.006] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2013] [Revised: 06/28/2013] [Accepted: 07/23/2013] [Indexed: 02/07/2023]
Abstract
Reproductive tract abnormalities and male infertility have higher incidence in ADPKD patients than in general populations. In this work, we reveal that Pkd1, whose mutations account for 85% of ADPKD cases, is essential for male reproductive tract development. Disruption of Pkd1 caused multiple organ defects in the murine male reproductive tract. The earliest visible defect in the Pkd1(-/-) reproductive tract was cystic dilation of the efferent ducts, which are derivatives of the mesonephric tubules. Epididymis development was delayed or arrested in the Pkd1(-/-) mice. No sign of epithelial coiling was seen in the null mutants. Disruption of Pkd1 in epithelium alone using the Pax2-cre mice was sufficient to cause efferent duct dilation and coiling defect in the epididymis, suggesting that Pkd1 is critical for epithelium development and maintenance in male reproductive tract. In-depth analysis showed that Pkd1 is required to maintain tubulin cytoskeleton and important for Tgf-β/Bmp signal transduction in epithelium of male reproductive tract. Altogether, our results for the first time provide direct evidence for developmental roles of Pkd1 in the male reproductive tract and provide new insights in reproductive tract abnormalities and infertility in ADPKD patients.
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Singh VP, Singh N, Jaggi AS. A review on renal toxicity profile of common abusive drugs. THE KOREAN JOURNAL OF PHYSIOLOGY & PHARMACOLOGY : OFFICIAL JOURNAL OF THE KOREAN PHYSIOLOGICAL SOCIETY AND THE KOREAN SOCIETY OF PHARMACOLOGY 2013; 17:347-57. [PMID: 23946695 PMCID: PMC3741492 DOI: 10.4196/kjpp.2013.17.4.347] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 05/09/2013] [Revised: 06/25/2013] [Accepted: 07/14/2013] [Indexed: 12/22/2022]
Abstract
Drug abuse has become a major social problem of the modern world and majority of these abusive drugs or their metabolites are excreted through the kidneys and, thus, the renal complications of these drugs are very common. Morphine, heroin, cocaine, nicotine and alcohol are the most commonly abused drugs, and their use is associated with various types of renal toxicity. The renal complications include a wide range of glomerular, interstitial and vascular diseases leading to acute or chronic renal failure. The present review discusses the renal toxicity profile and possible mechanisms of commonly abused drugs including morphine, heroin, cocaine, nicotine, caffeine and alcohol.
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Affiliation(s)
- Varun Parkash Singh
- Department of Pharmaceutical Sciences and Drug Research, Punjabi University, Patiala-147002, India
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Blanco G, Wallace DP. Novel role of ouabain as a cystogenic factor in autosomal dominant polycystic kidney disease. Am J Physiol Renal Physiol 2013; 305:F797-812. [PMID: 23761677 DOI: 10.1152/ajprenal.00248.2013] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
The classic role of the Na-K-ATPase is that of a primary active transporter that utilizes cell energy to establish and maintain transmembrane Na(+) and K(+) gradients to preserve cell osmotic stability, support cell excitability, and drive secondary active transport. Recent studies have revealed that Na-K-ATPase located within cholesterol-containing lipid rafts serves as a receptor for cardiotonic steroids, including ouabain. Traditionally, ouabain was viewed as a toxin produced only in plants, and it was used in relatively high concentrations to experimentally block the pumping action of the Na-K-ATPase. However, the new and unexpected role of the Na-K-ATPase as a signal transducer revealed a novel facet for ouabain in the regulation of a myriad of cell functions, including cell proliferation, hypertrophy, apoptosis, mobility, and metabolism. The seminal discovery that ouabain is endogenously produced in mammals and circulates in plasma has fueled the interest in this endogenous molecule as a potentially important hormone in normal physiology and disease. In this article, we review the role of the Na-K-ATPase as an ion transporter in the kidney, the experimental evidence for ouabain as a circulating hormone, the function of the Na-K-ATPase as a signal transducer that mediates ouabain's effects, and novel results for ouabain-induced Na-K-ATPase signaling in cystogenesis of autosomal dominant polycystic kidney disease.
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Affiliation(s)
- Gustavo Blanco
- Dept. of Molecular and Integrative Physiology, 3901 Rainbow Blvd., Kansas City, KS 66160.
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Spithoven EM, Meijer E, Boertien WE, Sinkeler SJ, Tent H, de Jong PE, Navis G, Gansevoort RT. Tubular secretion of creatinine in autosomal dominant polycystic kidney disease: consequences for cross-sectional and longitudinal performance of kidney function estimating equations. Am J Kidney Dis 2013; 62:531-40. [PMID: 23714171 DOI: 10.1053/j.ajkd.2013.03.030] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2012] [Accepted: 03/07/2013] [Indexed: 11/11/2022]
Abstract
BACKGROUND Autosomal dominant polycystic kidney disease (ADPKD) is characterized by renal tubular cell proliferation and dedifferentiation, which may influence tubular secretion of creatinine (CCr[TS]). STUDY DESIGN Diagnostic test study. SETTING & PARTICIPANTS We therefore investigated CCr(TS) in patients with ADPKD and controls and studied consequences for the performance of glomerular filtration rate (GFR) estimating equations. INDEX & REFERENCE TESTS In patients with ADPKD and healthy controls, we measured GFR as (125)I-iothalamate clearance while simultaneously determining creatinine clearance. OTHER MEASUREMENTS 24-hour urinary albumin excretion. RESULTS In 121 patients with ADPKD (56% men; mean age, 40 ± 11 [SD] years) and 215 controls (48% men; mean age, 53 ± 10 years), measured GFR (mGFR) was 78 ± 30 and 98 ± 17 mL/min/1.73 m(2), respectively, and CCr(TS) was 15.9 ± 10.8 and 10.9 ± 10.6 mL/min/1.73 m(2), respectively (P < 0.001). The higher CCr(TS) in patients with ADPKD remained significant after adjustment for covariates and appeared to be dependent on mGFR. Correlation and accuracy between mGFR and CKD-EPI (Chronic Kidney Disease Epidemiology Collaboration) estimated GFR (eGFR) were 0.95 and 99%, respectively; between mGFR and MDRD (Modification of Diet in Renal Disease) Study eGFR, they were 0.93 and 97%, respectively. Values for bias, precision, and accuracy were similar or slightly better than in controls. In addition, change in mGFR during 3 years of follow-up in 45 patients with ADPKD correlated well with change in eGFR. LIMITATIONS Cross-sectional, single center. CONCLUSIONS CCr(TS) in patients with ADPKD is higher than that in controls, but this effect is limited and observed at only high-normal mGFR. Consequently, the CKD-EPI and MDRD Study equations perform relatively well in estimating GFR and change in GFR in patients with ADPKD.
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Affiliation(s)
- Edwin M Spithoven
- Division of Nephrology, Department of Internal Medicine, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
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Yuajit C, Homvisasevongsa S, Chatsudthipong L, Soodvilai S, Muanprasat C, Chatsudthipong V. Steviol reduces MDCK Cyst formation and growth by inhibiting CFTR channel activity and promoting proteasome-mediated CFTR degradation. PLoS One 2013; 8:e58871. [PMID: 23536832 PMCID: PMC3594167 DOI: 10.1371/journal.pone.0058871] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2012] [Accepted: 02/07/2013] [Indexed: 01/26/2023] Open
Abstract
Cyst enlargement in polycystic kidney disease (PKD) involves cAMP-activated proliferation of cyst-lining epithelial cells and transepithelial fluid secretion into the cyst lumen via cystic fibrosis transmembrane conductance regulator (CFTR) chloride channel. This study aimed to investigate an inhibitory effect and detailed mechanisms of steviol and its derivatives on cyst growth using a cyst model in Madin-Darby canine kidney (MDCK) cells. Among 4 steviol-related compounds tested, steviol was found to be the most potent at inhibiting MDCK cyst growth. Steviol inhibition of cyst growth was dose-dependent; steviol (100 microM) reversibly inhibited cyst formation and cyst growth by 72.53.6% and 38.2±8.5%, respectively. Steviol at doses up to 200 microM had no effect on MDCK cell viability, proliferation and apoptosis. However, steviol acutely inhibited forskolin-stimulated apical chloride current in MDCK epithelia, measured with the Ussing chamber technique, in a dose-dependent manner. Prolonged treatment (24 h) with steviol (100 microM) also strongly inhibited forskolin-stimulated apical chloride current, in part by reducing CFTR protein expression in MDCK cells. Interestingly, proteasome inhibitor, MG-132, abolished the effect of steviol on CFTR protein expression. Immunofluorescence studies demonstrated that prolonged treatment (24 h) with steviol (100 microM) markedly reduced CFTR expression at the plasma membrane. Taken together, the data suggest that steviol retards MDCK cyst progression in two ways: first by directly inhibiting CFTR chloride channel activity and second by reducing CFTR expression, in part, by promoting proteasomal degradation of CFTR. Steviol and related compounds therefore represent drug candidates for treatment of polycystic kidney disease.
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Affiliation(s)
- Chaowalit Yuajit
- Department of Physiology, Faculty of Science, Mahidol University, Bangkok, Thailand
| | - Sureeporn Homvisasevongsa
- Division of Physical Science, Faculty of Science and Technology, Huachiew Chalermprakiet University, Samutprakarn, Thailand
| | - Lisa Chatsudthipong
- Department of Physiology, Faculty of Science, Mahidol University, Bangkok, Thailand
| | - Sunhapas Soodvilai
- Department of Physiology, Faculty of Science, Mahidol University, Bangkok, Thailand
- Research Center of Transport Protein for Medical Innovation, Faculty of Science, Mahidol University, Bangkok, Thailand
| | - Chatchai Muanprasat
- Department of Physiology, Faculty of Science, Mahidol University, Bangkok, Thailand
- Research Center of Transport Protein for Medical Innovation, Faculty of Science, Mahidol University, Bangkok, Thailand
| | - Varanuj Chatsudthipong
- Department of Physiology, Faculty of Science, Mahidol University, Bangkok, Thailand
- Research Center of Transport Protein for Medical Innovation, Faculty of Science, Mahidol University, Bangkok, Thailand
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Zaika O, Mamenko M, Berrout J, Boukelmoune N, O'Neil RG, Pochynyuk O. TRPV4 dysfunction promotes renal cystogenesis in autosomal recessive polycystic kidney disease. J Am Soc Nephrol 2013; 24:604-16. [PMID: 23411787 DOI: 10.1681/asn.2012050442] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
Abstract
The molecular mechanism of cyst formation and expansion in autosomal recessive polycystic kidney disease (ARPKD) is poorly understood, but impaired mechanosensitivity to tubular flow and dysfunctional calcium signaling are important contributors. The activity of the mechanosensitive Ca(2+)-permeable TRPV4 channel underlies flow-dependent Ca(2+) signaling in murine collecting duct (CD) cells, suggesting that this channel may contribute to cystogenesis in ARPKD. Here, we developed a method to isolate CD-derived cysts and studied TRPV4 function in these cysts laid open as monolayers and in nondilated split-open CDs in a rat model of ARPKD. In freshly isolated CD-derived cyst monolayers, we observed markedly impaired TRPV4 activity, abnormal subcellular localization of the channel, disrupted TRPV4 glycosylation, decreased basal [Ca(2+)]i, and loss of flow-mediated [Ca(2+)]i signaling. In contrast, nondilated CDs of these rats exhibited functional TRPV4 with largely preserved mechanosensitive properties. Long-term systemic augmentation of TRPV4 activity with a selective TRPV4 activator significantly attenuated the renal manifestations of ARPKD in a time-dependent manner. At the cellular level, selective activation of TRPV4 restored mechanosensitive Ca(2+) signaling as well as the function and subcellular distribution of TRPV4. In conclusion, the functional status of TRPV4, which underlies mechanosensitive Ca(2+) signaling in CD cells, inversely correlates with renal cystogenesis in ARPKD. Augmenting TRPV4 activity may have therapeutic potential in ARPKD.
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Affiliation(s)
- Oleg Zaika
- Department of Integrative Biology and Pharmacology, University of Texas Health Science Center at Houston, 6431 Fannin, Houston, TX 77030, USA
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Abstract
Claudins are tight junction membrane proteins that regulate paracellular permeability of renal epithelia to small ions, solutes, and water. Claudins interact within the cell membrane and between neighboring cells to form tight junction strands and constitute both the paracellular barrier and the pore. The first extracellular domain of claudins is thought to be the pore-lining domain and contains the determinants of charge selectivity. Multiple claudins are expressed in different nephron segments; such differential expression likely determines the permeability properties of each segment. Recent evidence has identified claudin-2 as constituting the cation-reabsorptive pathway in the proximal tubule; claudin-14, -16, and -19 as forming a complex that regulates calcium transport in the thick ascending limb of the loop of Henle; and claudin-4, -7, and -8 as determinants of collecting duct chloride permeability. Mutations in claudin-16 and -19 cause familial hypercalciuric hypomagnesemia with nephrocalcinosis. The roles of other claudins in kidney diseases remain to be fully elucidated.
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Affiliation(s)
- Jianghui Hou
- Renal Division, Washington University, St. Louis, Missouri 63110, USA
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Jansson K, Nguyen ANT, Magenheimer BS, Reif GA, Aramadhaka LR, Bello-Reuss E, Wallace DP, Calvet JP, Blanco G. Endogenous concentrations of ouabain act as a cofactor to stimulate fluid secretion and cyst growth of in vitro ADPKD models via cAMP and EGFR-Src-MEK pathways. Am J Physiol Renal Physiol 2012; 303:F982-90. [PMID: 22859406 PMCID: PMC3469686 DOI: 10.1152/ajprenal.00677.2011] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2011] [Accepted: 07/26/2012] [Indexed: 01/26/2023] Open
Abstract
In autosomal-dominant polycystic kidney disease (ADPKD), renal cysts develop by aberrant epithelial cell proliferation and transepithelial fluid secretion. We previously showed that ouabain increases proliferation of cultured human ADPKD cells via stimulation of the EGF receptor (EGFR)-Src-MEK/ERK signaling pathway. We examined whether ouabain affects fluid secretion and in vitro cyst growth of human ADPKD cell monolayers, ADPKD cell microcysts cultured in a three-dimensional collagen matrix, and metanephric organ cultures from Pkd1(m1Bei) mice. Physiological concentrations of ouabain alone did not affect net transepithelial basal-to-apical fluid transport in ADPKD monolayers or growth of cultured ADPKD microcysts. In contrast, in the presence of forskolin or 8-bromo-cAMP, ouabain significantly enhanced ADPKD fluid secretion and microcyst expansion. Ouabain exerted this effect by enhancing cAMP-dependent Cl(-) secretion via the CFTR. Similarly, ouabain accelerated cAMP-dependent cyst enlargement in Pkd1(m1Bei) mice metanephroi, with a more prominent response in homozygous than heterozygous mice. Ouabain had no effect on fluid secretion and cystogenesis of normal human kidney cells and caused only slight cystic dilations in wild-type mouse kidneys. The effects of ouabain in ADPKD cells and Pkd1(m1Bei) metanephroi were prevented by inhibitors of EGFR (AG1478), Src (PP2), and MEK (U0126). Together, our results show that ouabain, used in physiological concentrations, has synergistic effects on cAMP-mediated fluid secretion and cyst growth, via activation of the EGFR-Src-MEK pathway. These data provide important evidence for the role of ouabain as an endogenous hormone that exacerbates ADPKD cyst progression.
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Affiliation(s)
- Kyle Jansson
- Dept. of Molecular and Integrative Physiology, 3901 Rainbow Blvd., Kansas City, KS 66160, USA
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Subramanian B, Ko WC, Yadav V, DesRochers TM, Perrone RD, Zhou J, Kaplan DL. The regulation of cystogenesis in a tissue engineered kidney disease system by abnormal matrix interactions. Biomaterials 2012; 33:8383-94. [PMID: 22940218 DOI: 10.1016/j.biomaterials.2012.08.020] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2012] [Accepted: 08/10/2012] [Indexed: 11/17/2022]
Abstract
Autosomal Dominant Polycystic Kidney Disease (ADPKD) remains a major health care concern affecting several million patients worldwide and for which there is no specific treatment. We have employed a 3D tissue engineered disease-like system to emulate cystic structures in vitro and analyzed the extracellular matrix (ECM) interactions in it. The tissue system was developed by culturing normal or polycystin-1 silenced mouse Inner Medullary Collecting Duct (mIMCD) cells in ECM infused into 3D porous silk protein biomaterial scaffolds. In this system, the silk scaffolds provide slow degradation, biocompatibility, and maintain structure and transport for the 3D system, while the ECM molecules retain biological signaling. Using this 3D tissue system we provide evidence for an autocrine signaling loop involving abnormal matrix deposition (collagen type IV and laminin) and its integrin receptor subunit protein (Integrin-β1) in Pkd1 silenced mIMCD cells. In addition, we report that abnormal pericystic ECM interactions between matrix molecules and integrin subunit proteins regulate the rate of cystogenesis in the disease system. Molecular signaling showed abnormalities in cyclin proteins and cell-cycle progression upon Pkd1 knockdown. Importantly, disruption of the abnormal matrix interactions by an additional knockdown (double-silencing) of integrin-β1 in Pkd1 silenced cells reversed the abnormalities and reduced the rate of cystogenesis. Together, these findings indicate that abnormal matrix deposition and altered integrin profile distribution as observed in ADPKD and are critical in cystogenesis and should be considered a target for the development of therapeutics.
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Olteanu D, Liu X, Liu W, Roper VC, Sharma N, Yoder BK, Satlin LM, Schwiebert EM, Bevensee MO. Increased Na+/H+ exchanger activity on the apical surface of a cilium-deficient cortical collecting duct principal cell model of polycystic kidney disease. Am J Physiol Cell Physiol 2012; 302:C1436-51. [PMID: 22301060 DOI: 10.1152/ajpcell.00063.2011] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Pathophysiological anomalies in autosomal dominant and recessive forms of polycystic kidney disease (PKD) may derive from impaired function/formation of the apical central monocilium of ductal epithelia such as that seen in the Oak Ridge polycystic kidney or orpk (Ift88(Tg737Rpw)) mouse and its immortalized cell models for the renal collecting duct. According to a previous study, Na/H exchanger (NHE) activity may contribute to hyperabsorptive Na(+) movement in cilium-deficient ("mutant") cortical collecting duct principal cell monolayers derived from the orpk mice compared with cilium-competent ("rescued") monolayers. To examine NHE activity, we measured intracellular pH (pH(i)) by fluorescence imaging with the pH-sensitive dye BCECF, and used a custom-designed perfusion chamber to control the apical and basolateral solutions independently. Both mutant and rescued monolayers exhibited basolateral Na(+)-dependent acid-base transporter activity in the nominal absence of CO(2)/HCO(3)(-). However, only the mutant cells displayed appreciable apical Na(+)-induced pH(i) recoveries from NH(4)(+) prepulse-induced acid loads. Similar results were obtained with isolated, perfused collecting ducts from orpk vs. wild-type mice. The pH(i) dependence of basolateral cariporide/HOE-694-sensitive NHE activity under our experimental conditions was similar in both mutant and rescued cells, and 3.5- to 4.5-fold greater than apical HOE-sensitive NHE activity in the mutant cells (pH(i) 6.23-6.68). Increased apical NHE activity correlated with increased apical NHE1 expression in the mutant cells, and increased apical localization in collecting ducts of kidney sections from orpk vs. control mice. A kidney-specific conditional cilium-knockout mouse produced a more acidic urine compared with wild-type littermates and became alkalotic by 28 days of age. This study provides the first description of altered NHE activity, and an associated acid-base anomaly in any form of PKD.
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Affiliation(s)
- Dragos Olteanu
- Department of Physiology and Biophysics, University of Alabama at Birmingham, Birmingham, AL 35294, USA
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