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Yufang W, Mingfang L, Nan H, Tingting W. Quercetin-targeted AKT1 regulates the Raf/MEK/ERK signaling pathway to protect against doxorubicin-induced nephropathy in mice. Tissue Cell 2023; 85:102229. [PMID: 37812949 DOI: 10.1016/j.tice.2023.102229] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2023] [Revised: 09/25/2023] [Accepted: 09/28/2023] [Indexed: 10/11/2023]
Abstract
BACKGROUND Doxorubicin is an anthracycline antitumor agent commonly used in clinical practice, which has some nephrotoxicity and is often used to establish mouse models of kidney injury for basic medical research. This study will investigate the protective effect of quercetin on renal function in doxorubicin-induced nephropathy mice. METHODS C57BL/6 mice were divided into control, model, and quercetin low-, and high-dose groups. Serum and urine were collected to analyze markers of kidney function. H&E staining was used to detect pathological changes in renal tissues. Transmission electron microscopy was performed to observe the ultrastructural changes in renal tissues. Immunohistochemistry was performed to detect the changes of Ang II. RT-qPCR was performed to detect the changes of cytokines. ELISA was used to detect changes in serum inflammatory factors. Molecular docking was performed to verify the targeting relationship between quercetin and AKT1. Western blot was performed to detect Bax, Bcl-2, Cyt-c, AKT1, Raf, MEK, and ERK proteins. RESULTS Quercetin could induce the recovery of kidney function in kidney-injured mice; H&E results showed that kidney tissue damage and tissue fibrosis were reduced in kidney-injured mice under quercetin. The mitochondrial swollen structure was destroyed by doxorubicin, while the mitochondrial structure was restored under quercetin. The levels of abnormal apoptotic proteins Bax and Bcl-2 were regulated to normal by quercetin. The high expression of Ang II caused by doxorubicin was down-regulated by quercetin. Abnormal inflammatory factors caused by doxorubicin were reversed by quercetin. Western blot experiments showed that quercetin regulated the protein levels of AKT1 and Raf/MEK/ERK and inhibited the detrimental effects of doxorubicin. CONCLUSION Quercetin may mitigate doxorubicin-induced kidney injury in mice by regulating renal cell inflammatory factors and Raf/MEK/ERK signaling pathway through AKT1 to promote recovery of renal function.
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Affiliation(s)
- Wang Yufang
- Department of Medical Laboratory Diagnosis Lecturer, Quanzhou Medical College, Quanzhou, Fujian Province, China.
| | - Liu Mingfang
- The Second Attached Hospital of Fujian Medical University, Quanzhou, Fujian Province, China
| | - Huang Nan
- Department of Medical Laboratory Diagnosis Lecturer, Quanzhou Medical College, Quanzhou, Fujian Province, China
| | - Wang Tingting
- Department of Medical Laboratory Diagnosis Lecturer, Quanzhou Medical College, Quanzhou, Fujian Province, China
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2
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Rothé B, Fortier S, Gagnieux C, Schmuziger C, Constam DB. Antagonistic interactions among structured domains in the multivalent Bicc1-ANKS3-ANKS6 protein network govern phase transitioning of target mRNAs. iScience 2023; 26:106855. [PMID: 37275520 PMCID: PMC10232731 DOI: 10.1016/j.isci.2023.106855] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2022] [Revised: 04/11/2023] [Accepted: 05/05/2023] [Indexed: 06/07/2023] Open
Abstract
The growing number of diseases linked to aberrant phase transitioning of ribonucleoproteins highlights the need to uncover how the interplay between multivalent protein and RNA interactions is regulated. Cytoplasmic granules of the RNA binding protein Bicaudal-C (Bicc1) are regulated by the ciliopathy proteins ankyrin (ANK) and sterile alpha motif (SAM) domain-containing ANKS3 and ANKS6, but whether and how target mRNAs are affected is unknown. Here, we show that head-to-tail polymers of Bicc1 nucleated by its SAM domain are interconnected by K homology (KH) domains in a protein meshwork that mediates liquid-to-gel transitioning of client transcripts. Moreover, while the dispersion of these granules by ANKS3 concomitantly released bound mRNAs, co-recruitment of ANKS6 by ANKS3 reinstated Bicc1 condensation and ribonucleoparticle assembly. RNA-independent Bicc1 polymerization and its dual regulation by ANKS3 and ANKS6 represent a new mechanism to couple the reversible immobilization of client mRNAs to controlled protein phase transitioning between distinct metastable states.
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Affiliation(s)
- Benjamin Rothé
- Ecole Polytechnique Fédérale de Lausanne (EPFL) SV ISREC, Station 19, 1015 Lausanne, Switzerland
| | - Simon Fortier
- Ecole Polytechnique Fédérale de Lausanne (EPFL) SV ISREC, Station 19, 1015 Lausanne, Switzerland
| | - Céline Gagnieux
- Ecole Polytechnique Fédérale de Lausanne (EPFL) SV ISREC, Station 19, 1015 Lausanne, Switzerland
| | - Céline Schmuziger
- Ecole Polytechnique Fédérale de Lausanne (EPFL) SV ISREC, Station 19, 1015 Lausanne, Switzerland
| | - Daniel B. Constam
- Ecole Polytechnique Fédérale de Lausanne (EPFL) SV ISREC, Station 19, 1015 Lausanne, Switzerland
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3
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Paolocci E, Zaccolo M. Compartmentalised cAMP signalling in the primary cilium. Front Physiol 2023; 14:1187134. [PMID: 37256063 PMCID: PMC10226274 DOI: 10.3389/fphys.2023.1187134] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2023] [Accepted: 04/25/2023] [Indexed: 06/01/2023] Open
Abstract
cAMP is a universal second messenger that relies on precise spatio-temporal regulation to control varied, and often opposing, cellular functions. This is achieved via selective activation of effectors embedded in multiprotein complexes, or signalosomes, that reside at distinct subcellular locations. cAMP is also one of many pathways known to operate within the primary cilium. Dysfunction of ciliary signaling leads to a class of diseases known as ciliopathies. In Autosomal Dominant Polycystic Kidney Disease (ADPKD), a ciliopathy characterized by the formation of fluid-filled kidney cysts, upregulation of cAMP signaling is known to drive cystogenesis. For decades it has been debated whether the primary cilium is an independent cAMP sub-compartment, or whether it shares a diffusible pool of cAMP with the cell body. Recent studies now suggest it is a specific pool of cAMP generated in the cilium that propels cyst formation in ADPKD, supporting the notion that this antenna-like organelle is a compartment within which cAMP signaling occurs independently from cAMP signaling in the bulk cytosol. Here we present examples of cAMP function in the cilium which suggest this mysterious organelle is home to more than one cAMP signalosome. We review evidence that ciliary membrane localization of G-Protein Coupled Receptors (GPCRs) determines their downstream function and discuss how optogenetic tools have contributed to establish that cAMP generated in the primary cilium can drive cystogenesis.
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4
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Devlin L, Dhondurao Sudhindar P, Sayer JA. Renal ciliopathies: promising drug targets and prospects for clinical trials. Expert Opin Ther Targets 2023; 27:325-346. [PMID: 37243567 DOI: 10.1080/14728222.2023.2218616] [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: 03/06/2023] [Revised: 05/12/2023] [Accepted: 05/23/2023] [Indexed: 05/29/2023]
Abstract
INTRODUCTION Renal ciliopathies represent a collection of genetic disorders characterized by deficiencies in the biogenesis, maintenance, or functioning of the ciliary complex. These disorders, which encompass autosomal dominant polycystic kidney disease (ADPKD), autosomal recessive polycystic kidney disease (ARPKD), and nephronophthisis (NPHP), typically result in cystic kidney disease, renal fibrosis, and a gradual deterioration of kidney function, culminating in kidney failure. AREAS COVERED Here we review the advances in basic science and clinical research into renal ciliopathies which have yielded promising small compounds and drug targets, within both preclinical studies and clinical trials. EXPERT OPINION Tolvaptan is currently the sole approved treatment option available for ADPKD patients, while no approved treatment alternatives exist for ARPKD or NPHP patients. Clinical trials are presently underway to evaluate additional medications in ADPKD and ARPKD patients. Based on preclinical models, other potential therapeutic targets for ADPKD, ARPKD, and NPHP look promising. These include molecules targeting fluid transport, cellular metabolism, ciliary signaling and cell-cycle regulation. There is a real and urgent clinical need for translational research to bring novel treatments to clinical use for all forms of renal ciliopathies to reduce kidney disease progression and prevent kidney failure.
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Affiliation(s)
- Laura Devlin
- Translational and Clinical Research Institute, Faculty of Medical Sciences, Newcastle University, Newcastle Upon Tyne, UK
| | - Praveen Dhondurao Sudhindar
- Translational and Clinical Research Institute, Faculty of Medical Sciences, Newcastle University, Newcastle Upon Tyne, UK
| | - John A Sayer
- Translational and Clinical Research Institute, Faculty of Medical Sciences, Newcastle University, Newcastle Upon Tyne, UK
- Renal Services, Newcastle Upon Tyne Hospitals NHS Foundation Trust, Newcastle Upon Tyne, UK
- NIHR Newcastle Biomedical Research Centre, Newcastle Upon Tyne, UK
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5
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Parnell SC, Raman A, Zhang Y, Daniel EA, Dai Y, Khanna A, Reif GA, Vivian JL, Fields TA, Wallace DP. Expression of active B-Raf proto-oncogene in kidney collecting ducts induces cyst formation in normal mice and accelerates cyst growth in mice with polycystic kidney disease. Kidney Int 2022; 102:1103-1114. [PMID: 35760151 PMCID: PMC9588601 DOI: 10.1016/j.kint.2022.05.028] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2021] [Revised: 05/10/2022] [Accepted: 05/13/2022] [Indexed: 12/14/2022]
Abstract
Polycystic kidney disease (PKD) is characterized by the formation and progressive enlargement of fluid-filled cysts due to abnormal cell proliferation. Cyclic AMP agonists, including arginine vasopressin, stimulate ERK-dependent proliferation of cystic cells, but not normal kidney cells. Previously, B-Raf proto-oncogene (BRAF), a MAPK kinase kinase that activates MEK-ERK signaling, was shown to be a central intermediate in the cAMP mitogenic response. However, the role of BRAF on cyst formation and enlargement in vivo had not been demonstrated. To determine if active BRAF induces kidney cyst formation, we generated transgenic mice that conditionally express BRAFV600E, a common activating mutation, and bred them with Pkhd1-Cre mice to express active BRAF in the collecting ducts, a predominant site for cyst formation. Collecting duct expression of BRAFV600E (BRafCD) caused kidney cyst formation as early as three weeks of age. There were increased levels of phosphorylated ERK (p-ERK) and proliferating cell nuclear antigen, a marker for cell proliferation. BRafCD mice developed extensive kidney fibrosis and elevated blood urea nitrogen, indicating a decline in kidney function, by ten weeks of age. BRAFV600E transgenic mice were also bred to Pkd1RC/RC and pcy/pcy mice, well-characterized slowly progressive PKD models. Collecting duct expression of active BRAF markedly increased kidney weight/body weight, cyst number and size, and total cystic area. There were increased p-ERK levels and proliferating cells, immune cell infiltration, interstitial fibrosis, and a decline in kidney function in both these models. Thus, our findings demonstrate that active BRAF is sufficient to induce kidney cyst formation in normal mice and accelerate cystic disease in PKD mice.
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Affiliation(s)
- Stephen C Parnell
- Department of Biochemistry and Molecular Biology, The Jared Grantham Kidney Institute, University of Kansas Medical Center, Kansas City, Kansas, USA
| | - Archana Raman
- Department of Molecular and Integrative Physiology, The Jared Grantham Kidney Institute, University of Kansas Medical Center, Kansas City, Kansas, USA
| | - Yan Zhang
- Department of Internal Medicine, The Jared Grantham Kidney Institute, University of Kansas Medical Center, Kansas City, Kansas, USA
| | - Emily A Daniel
- Department of Internal Medicine, The Jared Grantham Kidney Institute, University of Kansas Medical Center, Kansas City, Kansas, USA
| | - Yuqiao Dai
- Department of Internal Medicine, The Jared Grantham Kidney Institute, University of Kansas Medical Center, Kansas City, Kansas, USA
| | - Aditi Khanna
- Department of Internal Medicine, The Jared Grantham Kidney Institute, University of Kansas Medical Center, Kansas City, Kansas, USA
| | - Gail A Reif
- Department of Internal Medicine, The Jared Grantham Kidney Institute, University of Kansas Medical Center, Kansas City, Kansas, USA
| | - Jay L Vivian
- Department of Pathology and Laboratory Medicine, The Jared Grantham Kidney Institute, University of Kansas Medical Center, Kansas City, Kansas, USA
| | - Timothy A Fields
- Department of Pathology and Laboratory Medicine, The Jared Grantham Kidney Institute, University of Kansas Medical Center, Kansas City, Kansas, USA
| | - Darren P Wallace
- Department of Molecular and Integrative Physiology, The Jared Grantham Kidney Institute, University of Kansas Medical Center, Kansas City, Kansas, USA; Department of Internal Medicine, The Jared Grantham Kidney Institute, University of Kansas Medical Center, Kansas City, Kansas, USA.
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6
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Zhou X, Torres VE. Emerging therapies for autosomal dominant polycystic kidney disease with a focus on cAMP signaling. Front Mol Biosci 2022; 9:981963. [PMID: 36120538 PMCID: PMC9478168 DOI: 10.3389/fmolb.2022.981963] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2022] [Accepted: 08/05/2022] [Indexed: 11/29/2022] Open
Abstract
Autosomal dominant polycystic kidney disease (ADPKD), with an estimated genetic prevalence between 1:400 and 1:1,000 individuals, is the third most common cause of end stage kidney disease after diabetes mellitus and hypertension. Over the last 3 decades there has been great progress in understanding its pathogenesis. This allows the stratification of therapeutic targets into four levels, gene mutation and polycystin disruption, proximal mechanisms directly caused by disruption of polycystin function, downstream regulatory and signaling pathways, and non-specific pathophysiologic processes shared by many other diseases. Dysfunction of the polycystins, encoded by the PKD genes, is closely associated with disruption of calcium and upregulation of cyclic AMP and protein kinase A (PKA) signaling, affecting most downstream regulatory, signaling, and pathophysiologic pathways altered in this disease. Interventions acting on G protein coupled receptors to inhibit of 3',5'-cyclic adenosine monophosphate (cAMP) production have been effective in preclinical trials and have led to the first approved treatment for ADPKD. However, completely blocking cAMP mediated PKA activation is not feasible and PKA activation independently from cAMP can also occur in ADPKD. Therefore, targeting the cAMP/PKA/CREB pathway beyond cAMP production makes sense. Redundancy of mechanisms, numerous positive and negative feedback loops, and possibly counteracting effects may limit the effectiveness of targeting downstream pathways. Nevertheless, interventions targeting important regulatory, signaling and pathophysiologic pathways downstream from cAMP/PKA activation may provide additive or synergistic value and build on a strategy that has already had success. The purpose of this manuscript is to review the role of cAMP and PKA signaling and their multiple downstream pathways as potential targets for emergent therapies for ADPKD.
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Affiliation(s)
- Xia Zhou
- Mayo Clinic, Department of Nephrology, Rochester, MN, United States
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7
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Walker RV, Maranto A, Palicharla VR, Hwang SH, Mukhopadhyay S, Qian F. Cilia-Localized Counterregulatory Signals as Drivers of Renal Cystogenesis. Front Mol Biosci 2022; 9:936070. [PMID: 35832738 PMCID: PMC9272769 DOI: 10.3389/fmolb.2022.936070] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2022] [Accepted: 05/30/2022] [Indexed: 12/18/2022] Open
Abstract
Primary cilia play counterregulatory roles in cystogenesis-they inhibit cyst formation in the normal renal tubule but promote cyst growth when the function of polycystins is impaired. Key upstream cilia-specific signals and components involved in driving cystogenesis have remained elusive. Recent studies of the tubby family protein, Tubby-like protein 3 (TULP3), have provided new insights into the cilia-localized mechanisms that determine cyst growth. TULP3 is a key adapter of the intraflagellar transport complex A (IFT-A) in the trafficking of multiple proteins specifically into the ciliary membrane. Loss of TULP3 results in the selective exclusion of its cargoes from cilia without affecting their extraciliary pools and without disrupting cilia or IFT-A complex integrity. Epistasis analyses have indicated that TULP3 inhibits cystogenesis independently of the polycystins during kidney development but promotes cystogenesis in adults when polycystins are lacking. In this review, we discuss the current model of the cilia-dependent cyst activation (CDCA) mechanism in autosomal dominant polycystic kidney disease (ADPKD) and consider the possible roles of ciliary and extraciliary polycystins in regulating CDCA. We then describe the limitations of this model in not fully accounting for how cilia single knockouts cause significant cystic changes either in the presence or absence of polycystins. Based on available data from TULP3/IFT-A-mediated differential regulation of cystogenesis in kidneys with deletion of polycystins either during development or in adulthood, we hypothesize the existence of cilia-localized components of CDCA (cCDCA) and cilia-localized cyst inhibition (CLCI) signals. We develop the criteria for cCDCA/CLCI signals and discuss potential TULP3 cargoes as possible cilia-localized components that determine cystogenesis in kidneys during development and in adult mice.
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Affiliation(s)
- Rebecca V. Walker
- Division of Nephrology, Department of Medicine, University of Maryland School of Medicine, Baltimore, MD, United States
| | - Anthony Maranto
- Division of Nephrology, Department of Medicine, University of Maryland School of Medicine, Baltimore, MD, United States
| | | | - Sun-Hee Hwang
- Department of Cell Biology, UT Southwestern Medical Center, Dallas, TX, United States
| | - Saikat Mukhopadhyay
- Department of Cell Biology, UT Southwestern Medical Center, Dallas, TX, United States
| | - Feng Qian
- Division of Nephrology, Department of Medicine, University of Maryland School of Medicine, Baltimore, MD, United States
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8
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Scholz JK, Kraus A, Lüder D, Skoczynski K, Schiffer M, Grampp S, Schödel J, Buchholz B. Loss of Polycystin-1 causes cAMP-dependent switch from tubule to cyst formation. iScience 2022; 25:104359. [PMID: 35620436 PMCID: PMC9127160 DOI: 10.1016/j.isci.2022.104359] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2022] [Revised: 03/23/2022] [Accepted: 04/29/2022] [Indexed: 11/24/2022] Open
Abstract
Autosomal dominant polycystic kidney disease is the most common monogenic disease that causes end-stage renal failure. It primarily results from mutations in the PKD1 gene that encodes for Polycystin-1. How loss of Polycystin-1 translates into bilateral renal cyst development is mostly unknown. cAMP is significantly involved in cyst enlargement but its role in cyst initiation has remained elusive. Deletion of Polycystin-1 in collecting duct cells resulted in a switch from tubule to cyst formation and was accompanied by an increase in cAMP. Pharmacological elevation of cAMP in Polycystin-1-competent cells caused cyst formation, impaired plasticity, nondirectional migration, and mis-orientation, and thus strongly resembled the phenotype of Polycystin-1-deficient cells. Mis-orientation of developing tubule cells in metanephric kidneys upon loss of Polycystin-1 was phenocopied by pharmacological increase of cAMP in wildtype kidneys. In vitro, cAMP impaired tubule formation after capillary-induced injury which was further impaired by loss Polycystin-1. Loss of Polycystin-1 switches renal cells from tubule to cyst formation Deletion of Polycystin-1 leads to increase in cAMP Elevation of cAMP in wildtype cells phenocopies Polycystin-1-deficient features Features are: impaired plasticity, nondirectional migration, and mis-orientation
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9
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Kleene SJ. Regenerative Calcium Currents in Renal Primary Cilia. Front Physiol 2022; 13:894518. [PMID: 35620606 PMCID: PMC9127361 DOI: 10.3389/fphys.2022.894518] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2022] [Accepted: 04/18/2022] [Indexed: 11/13/2022] Open
Abstract
Polycystic kidney disease (PKD) is a leading cause of end-stage renal disease. PKD arises from mutations in proteins, one a Ca2+-conducting channel, expressed in the primary cilia of renal epithelial cells. A common hypothesis is that Ca2+ entering through ciliary ion channels may reduce cystogenesis. The cilia have at least two Ca2+-conducting channels: polycystin-2 (PC2) and TRPV4 (transient receptor potential (TRP) cation channel, subfamily V, member 4), but how substantially they can increase intraciliary Ca2+ is unknown. By recording channel activities in isolated cilia, conditions are identified under which the channels can increase free Ca2+ within the cilium by at least 500-fold through regenerative (positive-feedback) signaling. Ca2+ that has entered through a channel can activate the channel internally, which increases the Ca2+ influx, and so on. Regenerative signaling is favored when the concentration of the Ca2+ buffer is reduced or when a slower buffer is used. Under such conditions, the Ca2+ that enters the cilium through a single PC2 channel is sufficient to almost fully activate that same channel. Regenerative signaling is not detectable with reduced external Ca2+. Reduced buffering also allows regenerative signaling through TRPV4 channels, but not through TRPM4 (TRP subfamily M, member 4) channels, which are activated by Ca2+ but do not conduct it. On a larger scale, Ca2+ that enters through TRPV4 channels can cause secondary activation of PC2 channels. I discuss the likelihood of regenerative ciliary Ca2+ signaling in vivo, a possible mechanism for its activation, and how it might relate to cystogenesis.
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Affiliation(s)
- Steven J. Kleene
- Department of Pharmacology and Systems Physiology, University of Cincinnati, Cincinnati, OH, United States
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10
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Ostrom KF, LaVigne JE, Brust TF, Seifert R, Dessauer CW, Watts VJ, Ostrom RS. Physiological roles of mammalian transmembrane adenylyl cyclase isoforms. Physiol Rev 2022; 102:815-857. [PMID: 34698552 PMCID: PMC8759965 DOI: 10.1152/physrev.00013.2021] [Citation(s) in RCA: 38] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2021] [Revised: 09/20/2021] [Accepted: 10/19/2021] [Indexed: 12/12/2022] Open
Abstract
Adenylyl cyclases (ACs) catalyze the conversion of ATP to the ubiquitous second messenger cAMP. Mammals possess nine isoforms of transmembrane ACs, dubbed AC1-9, that serve as major effector enzymes of G protein-coupled receptors (GPCRs). The transmembrane ACs display varying expression patterns across tissues, giving the potential for them to have a wide array of physiological roles. Cells express multiple AC isoforms, implying that ACs have redundant functions. Furthermore, all transmembrane ACs are activated by Gαs, so it was long assumed that all ACs are activated by Gαs-coupled GPCRs. AC isoforms partition to different microdomains of the plasma membrane and form prearranged signaling complexes with specific GPCRs that contribute to cAMP signaling compartments. This compartmentation allows for a diversity of cellular and physiological responses by enabling unique signaling events to be triggered by different pools of cAMP. Isoform-specific pharmacological activators or inhibitors are lacking for most ACs, making knockdown and overexpression the primary tools for examining the physiological roles of a given isoform. Much progress has been made in understanding the physiological effects mediated through individual transmembrane ACs. GPCR-AC-cAMP signaling pathways play significant roles in regulating functions of every cell and tissue, so understanding each AC isoform's role holds potential for uncovering new approaches for treating a vast array of pathophysiological conditions.
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Affiliation(s)
| | - Justin E LaVigne
- Department of Medicinal Chemistry and Molecular Pharmacology, Purdue University, West Lafayette, Indiana
| | - Tarsis F Brust
- Department of Pharmaceutical Sciences, Lloyd L. Gregory School of Pharmacy, Palm Beach Atlantic University, West Palm Beach, Florida
| | - Roland Seifert
- Institute of Pharmacology, Hannover Medical School, Hannover, Germany
| | - Carmen W Dessauer
- Department of Integrative Biology and Pharmacology, McGovern Medical School, The University of Texas Health Sciences Center at Houston, Houston, Texas
| | - Val J Watts
- Department of Medicinal Chemistry and Molecular Pharmacology, Purdue University, West Lafayette, Indiana
- Purdue Institute for Drug Discovery, Purdue University, West Lafayette, Indiana
- Purdue Institute for Integrative Neuroscience, Purdue University, West Lafayette, Indiana
| | - Rennolds S Ostrom
- Department of Biomedical and Pharmaceutical Sciences, Chapman University School of Pharmacy, Irvine, California
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11
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Sudarikova A, Vasileva V, Sultanova R, Ilatovskaya D. Recent advances in understanding ion transport mechanisms in polycystic kidney disease. Clin Sci (Lond) 2021; 135:2521-2540. [PMID: 34751394 PMCID: PMC8589009 DOI: 10.1042/cs20210370] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2021] [Revised: 10/15/2021] [Accepted: 10/26/2021] [Indexed: 12/18/2022]
Abstract
This review focuses on the most recent advances in the understanding of the electrolyte transport-related mechanisms important for the development of severe inherited renal disorders, autosomal dominant (AD) and recessive (AR) forms of polycystic kidney disease (PKD). We provide here a basic overview of the origins and clinical aspects of ARPKD and ADPKD and discuss the implications of electrolyte transport in cystogenesis. Special attention is devoted to intracellular calcium handling by the cystic cells, with a focus on polycystins and fibrocystin, as well as other calcium level regulators, such as transient receptor potential vanilloid type 4 (TRPV4) channels, ciliary machinery, and purinergic receptor remodeling. Sodium transport is reviewed with a focus on the epithelial sodium channel (ENaC), and the role of chloride-dependent fluid secretion in cystic fluid accumulation is discussed. In addition, we highlight the emerging promising concepts in the field, such as potassium transport, and suggest some new avenues for research related to electrolyte handling.
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Affiliation(s)
| | | | - Regina F. Sultanova
- Saint-Petersburg State Chemical Pharmaceutical University, St. Petersburg, Russia
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12
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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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13
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Vasileva VY, Sultanova RF, Sudarikova AV, Ilatovskaya DV. Insights Into the Molecular Mechanisms of Polycystic Kidney Diseases. Front Physiol 2021; 12:693130. [PMID: 34566674 PMCID: PMC8456103 DOI: 10.3389/fphys.2021.693130] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2021] [Accepted: 08/10/2021] [Indexed: 12/18/2022] Open
Abstract
Autosomal dominant (AD) and autosomal recessive (AR) polycystic kidney diseases (PKD) are severe multisystem genetic disorders characterized with formation and uncontrolled growth of fluid-filled cysts in the kidney, the spread of which eventually leads to the loss of renal function. Currently, there are no treatments for ARPKD, and tolvaptan is the only FDA-approved drug that alleviates the symptoms of ADPKD. However, tolvaptan has only a modest effect on disease progression, and its long-term use is associated with many side effects. Therefore, there is still a pressing need to better understand the fundamental mechanisms behind PKD development. This review highlights current knowledge about the fundamental aspects of PKD development (with a focus on ADPKD) including the PC1/PC2 pathways and cilia-associated mechanisms, major molecular cascades related to metabolism, mitochondrial bioenergetics, and systemic responses (hormonal status, levels of growth factors, immune system, and microbiome) that affect its progression. In addition, we discuss new information regarding non-pharmacological therapies, such as dietary restrictions, which can potentially alleviate PKD.
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Affiliation(s)
| | - Regina F Sultanova
- Saint-Petersburg State Chemical Pharmaceutical University, St. Petersburg, Russia.,Department of Physiology, Augusta University, Augusta, GA, United States
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14
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Kinase-anchoring proteins in ciliary signal transduction. Biochem J 2021; 478:1617-1629. [PMID: 33909027 DOI: 10.1042/bcj20200869] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2021] [Revised: 03/23/2021] [Accepted: 03/29/2021] [Indexed: 12/16/2022]
Abstract
Historically, the diffusion of chemical signals through the cell was thought to occur within a cytoplasmic soup bounded by the plasma membrane. This theory was predicated on the notion that all regulatory enzymes are soluble and moved with a Brownian motion. Although enzyme compartmentalization was initially rebuffed by biochemists as a 'last refuge of a scoundrel', signal relay through macromolecular complexes is now accepted as a fundamental tenet of the burgeoning field of spatial biology. A-Kinase anchoring proteins (AKAPs) are prototypic enzyme-organizing elements that position clusters of regulatory proteins at defined subcellular locations. In parallel, the primary cilium has gained recognition as a subcellular mechanosensory organelle that amplifies second messenger signals pertaining to metazoan development. This article highlights advances in our understanding of AKAP signaling within the primary cilium and how defective ciliary function contributes to an increasing number of diseases known as ciliopathies.
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15
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Samidurai A, Xi L, Das A, Iness AN, Vigneshwar NG, Li PL, Singla DK, Muniyan S, Batra SK, Kukreja RC. Role of phosphodiesterase 1 in the pathophysiology of diseases and potential therapeutic opportunities. Pharmacol Ther 2021; 226:107858. [PMID: 33895190 DOI: 10.1016/j.pharmthera.2021.107858] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2020] [Revised: 03/17/2021] [Accepted: 04/14/2021] [Indexed: 12/15/2022]
Abstract
Cyclic nucleotide phosphodiesterases (PDEs) are superfamily of enzymes that regulate the spatial and temporal relationship of second messenger signaling in the cellular system. Among the 11 different families of PDEs, phosphodiesterase 1 (PDE1) sub-family of enzymes hydrolyze both 3',5'-cyclic adenosine monophosphate (cAMP) and 3',5'-cyclic guanosine monophosphate (cGMP) in a mutually competitive manner. The catalytic activity of PDE1 is stimulated by their binding to Ca2+/calmodulin (CaM), resulting in the integration of Ca2+ and cyclic nucleotide-mediated signaling in various diseases. The PDE1 family includes three subtypes, PDE1A, PDE1B and PDE1C, which differ for their relative affinities for cAMP and cGMP. These isoforms are differentially expressed throughout the body, including the cardiovascular, central nervous system and other organs. Thus, PDE1 enzymes play a critical role in the pathophysiology of diseases through the fundamental regulation of cAMP and cGMP signaling. This comprehensive review provides the current research on PDE1 and its potential utility as a therapeutic target in diseases including the cardiovascular, pulmonary, metabolic, neurocognitive, renal, cancers and possibly others.
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Affiliation(s)
- Arun Samidurai
- Division of Cardiology, Pauley Heart Center, Virginia Commonwealth University, Richmond, VA 23298-0204, USA
| | - Lei Xi
- Division of Cardiology, Pauley Heart Center, Virginia Commonwealth University, Richmond, VA 23298-0204, USA
| | - Anindita Das
- Division of Cardiology, Pauley Heart Center, Virginia Commonwealth University, Richmond, VA 23298-0204, USA
| | - Audra N Iness
- Division of Cardiology, Pauley Heart Center, Virginia Commonwealth University, Richmond, VA 23298-0204, USA
| | - Navin G Vigneshwar
- Division of Cardiology, Pauley Heart Center, Virginia Commonwealth University, Richmond, VA 23298-0204, USA
| | - Pin-Lan Li
- Department of Pharmacology and Toxicology, Virginia Commonwealth University, Richmond, VA 23298-0613, USA
| | - Dinender K Singla
- Division of Metabolic and Cardiovascular Sciences, Burnett School of Biomedical Sciences, College of Medicine, University of Central Florida, Orlando, FL 32816, USA
| | - Sakthivel Muniyan
- Department of Biochemistry and Molecular Biology, University of Nebraska Medical Center, Omaha, NE 68198-5870, USA
| | - Surinder K Batra
- Department of Biochemistry and Molecular Biology, University of Nebraska Medical Center, Omaha, NE 68198-5870, USA
| | - Rakesh C Kukreja
- Division of Cardiology, Pauley Heart Center, Virginia Commonwealth University, Richmond, VA 23298-0204, USA.
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16
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Duong Phu M, Bross S, Burkhalter MD, Philipp M. Limitations and opportunities in the pharmacotherapy of ciliopathies. Pharmacol Ther 2021; 225:107841. [PMID: 33771583 DOI: 10.1016/j.pharmthera.2021.107841] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2020] [Accepted: 03/11/2021] [Indexed: 01/10/2023]
Abstract
Ciliopathies are a family of rather diverse conditions, which have been grouped based on the finding of altered or dysfunctional cilia, potentially motile, small cellular antennae extending from the surface of postmitotic cells. Cilia-related disorders include embryonically arising conditions such as Joubert, Usher or Kartagener syndrome, but also afflictions with a postnatal or even adult onset phenotype, i.e. autosomal dominant polycystic kidney disease. The majority of ciliopathies are syndromic rather than affecting only a single organ due to cilia being found on almost any cell in the human body. Overall ciliopathies are considered rare diseases. Despite that, pharmacological research and the strive to help these patients has led to enormous therapeutic advances in the last decade. In this review we discuss new treatment options for certain ciliopathies, give an outlook on promising future therapeutic strategies, but also highlight the limitations in the development of therapeutic approaches of ciliopathies.
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Affiliation(s)
- Max Duong Phu
- Department of Experimental and Clinical Pharmacology and Pharmacogenomics, Section of Pharmacogenomics, Eberhard-Karls-University of Tübingen, 72074 Tübingen, Germany
| | - Stefan Bross
- Department of Experimental and Clinical Pharmacology and Pharmacogenomics, Section of Pharmacogenomics, Eberhard-Karls-University of Tübingen, 72074 Tübingen, Germany
| | - Martin D Burkhalter
- Department of Experimental and Clinical Pharmacology and Pharmacogenomics, Section of Pharmacogenomics, Eberhard-Karls-University of Tübingen, 72074 Tübingen, Germany
| | - Melanie Philipp
- Department of Experimental and Clinical Pharmacology and Pharmacogenomics, Section of Pharmacogenomics, Eberhard-Karls-University of Tübingen, 72074 Tübingen, Germany.
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Park SJ, Li C, Chen YM. Endoplasmic Reticulum Calcium Homeostasis in Kidney Disease: Pathogenesis and Therapeutic Targets. THE AMERICAN JOURNAL OF PATHOLOGY 2020; 191:256-265. [PMID: 33245915 DOI: 10.1016/j.ajpath.2020.11.006] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/25/2020] [Revised: 10/14/2020] [Accepted: 11/06/2020] [Indexed: 01/15/2023]
Abstract
Calcium (Ca2+) homeostasis is a crucial determinant of cellular function and survival. Endoplasmic reticulum (ER) acts as the largest intracellular Ca2+ store that maintains Ca2+ homeostasis through the ER Ca2+ uptake pump, sarco/ER Ca2+ ATPase, ER Ca2+ release channels, inositol 1,4,5-trisphosphate receptor channel, ryanodine receptor, and Ca2+-binding proteins inside of the ER lumen. Alterations in ER homeostasis trigger ER Ca2+ depletion and ER stress, which have been associated with the development of a variety of diseases. In addition, recent studies have highlighted the role of ER Ca2+ imbalance caused by dysfunction of sarco/ER Ca2+ ATPase, ryanodine receptor, and inositol 1,4,5-trisphosphate receptor channel in various kidney diseases. Despite progress in the understanding of the importance of these ER Ca2+ channels, pumps, and binding proteins in the pathogenesis of kidney disease, treatment is still lacking. This mini-review is focused on: i) Ca2+ homeostasis in the ER, ii) ER Ca2+ dyshomeostasis and apoptosis, and iii) altered ER Ca2+ homeostasis in kidney disease, including podocytopathy, diabetic nephropathy, albuminuria, autosomal dominant polycystic kidney disease, and ischemia/reperfusion-induced acute kidney injury.
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Affiliation(s)
- Sun-Ji Park
- Division of Nephrology, Department of Medicine, Washington University School of Medicine, St. Louis, Missouri
| | - Chuang Li
- Division of Nephrology, Department of Medicine, Washington University School of Medicine, St. Louis, Missouri
| | - Ying Maggie Chen
- Division of Nephrology, Department of Medicine, Washington University School of Medicine, St. Louis, Missouri.
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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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Establishing and regulating the composition of cilia for signal transduction. Nat Rev Mol Cell Biol 2020; 20:389-405. [PMID: 30948801 DOI: 10.1038/s41580-019-0116-4] [Citation(s) in RCA: 246] [Impact Index Per Article: 61.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The primary cilium is a hair-like surface-exposed organelle of the eukaryotic cell that decodes a variety of signals - such as odorants, light and Hedgehog morphogens - by altering the local concentrations and activities of signalling proteins. Signalling within the cilium is conveyed through a diverse array of second messengers, including conventional signalling molecules (such as cAMP) and some unusual intermediates (such as sterols). Diffusion barriers at the ciliary base establish the unique composition of this signalling compartment, and cilia adapt their proteome to signalling demands through regulated protein trafficking. Much progress has been made on the molecular understanding of regulated ciliary trafficking, which encompasses not only exchanges between the cilium and the rest of the cell but also the shedding of signalling factors into extracellular vesicles.
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20
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Torres VE. Pro: Tolvaptan delays the progression of autosomal dominant polycystic kidney disease. Nephrol Dial Transplant 2019; 34:30-34. [PMID: 30312438 DOI: 10.1093/ndt/gfy297] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2018] [Accepted: 06/13/2018] [Indexed: 12/28/2022] Open
Abstract
No treatment until now has directly targeted the mechanisms responsible for the development and growth of cysts in autosomal dominant polycystic kidney disease (ADPKD). Strong rationale and preclinical studies using in vitro and in vivo models justified the launching of two large phase 3 clinical trials of tolvaptan in early and later stages of ADPKD. Their design was based on preliminary studies informing on the pharmacokinetics, pharmacodynamics, short-term safety and self-reported tolerability in patients with ADPKD. Tolvaptan slowed kidney growth in the early stage and estimated glomerular filtration rate decline in early and later stages of the disease. All participants had the opportunity to enroll in open-label extension trials to ascertain long-term safety and efficacy. In a single-center analysis of long-term outcomes, the effect of tolvaptan was sustained and cumulative over time supporting a disease-modifying effect of tolvaptan in ADPKD. In the countries where tolvaptan has been approved by regulatory agencies, patients with rapidly progressive ADPKD should be informed about the option of treatment including possible benefits and risks. If a decision to initiate treatment is made, prescribing physicians should educate the patients on the prevention of aquaresis-related adverse events and should be vigilant in the surveillance and management of the potential tolvaptan hepatotoxicity. Other vasopressin V2 receptor antagonists, possibly without potential hepatotoxicity, alternative strategies targeting vasopressin and combination with other drugs able to enhance the efficacy or reduce the aquaresis associated with tolvaptan, deserve further study.
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21
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The pathobiology of polycystic kidney disease from a metabolic viewpoint. Nat Rev Nephrol 2019; 15:735-749. [PMID: 31488901 DOI: 10.1038/s41581-019-0183-y] [Citation(s) in RCA: 64] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/17/2019] [Indexed: 02/07/2023]
Abstract
Autosomal dominant polycystic kidney disease (ADPKD) affects an estimated 1 in 1,000 people and slowly progresses to end-stage renal disease (ESRD) in about half of these individuals. Tolvaptan, a vasopressin 2 receptor blocker, has been approved by regulatory authorities in many countries as a therapy to slow cyst growth, but additional treatments that target dysregulated signalling pathways in cystic kidney and liver are needed. Metabolic reprogramming is a prominent feature of cystic cells and a potentially important contributor to the pathophysiology of ADPKD. A number of pathways previously implicated in the pathogenesis of the disease, such as dysregulated mTOR and primary ciliary signalling, have roles in metabolic regulation and may exert their effects through this mechanism. Some of these pathways are amenable to manipulation through dietary modifications or drug therapies. Studies suggest that polycystin-1 and polycystin-2, which are encoded by PKD1 and PKD2, respectively (the genes that are mutated in >99% of patients with ADPKD), may in part affect cellular metabolism through direct effects on mitochondrial function. Mitochondrial dysfunction could alter the redox state and cellular levels of acetyl-CoA, resulting in altered histone acetylation, gene expression, cytoskeletal architecture and response to cellular stress, and in an immunological response that further promotes cyst growth and fibrosis.
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22
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Foo JN, Xia Y. Polycystic kidney disease: new knowledge and future promises. Curr Opin Genet Dev 2019; 56:69-75. [PMID: 31476629 DOI: 10.1016/j.gde.2019.06.007] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2019] [Revised: 05/27/2019] [Accepted: 06/11/2019] [Indexed: 02/06/2023]
Abstract
Polycystic kidney disease (PKD) is one of the most common genetic kidney diseases, characterized by the formation of fluid-filled renal cysts, which eventually lead to end-stage renal disease. Despite several decades of investigation, explicit molecular and cellular mechanisms underpinning renal cyst formation have been unresolved until recently, severely hampering the development of effective therapeutic approaches. Currently, most PKD therapies have been developed for limiting disease complications, such as hypertension. Although Tolvaptan has been approved for treating PKD in few countries, the associated hepatic toxicity remains a major concern. In this Review, we will discuss recent advances in PKD research, covering aspects ranging from newly identified genetic/epigenetic causes, increment in mechanistic interpretation, novel therapeutic targets, to the promises offered by emerging stem cell technologies.
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Affiliation(s)
- Jia Nee Foo
- Lee Kong Chian School of Medicine, Nanyang Technological University Singapore, 11 Mandalay Road, 308232, Singapore; Human Genetics, Genome Institute of Singapore, A(⁎)STAR, 138672, Singapore.
| | - Yun Xia
- Lee Kong Chian School of Medicine, Nanyang Technological University Singapore, 11 Mandalay Road, 308232, Singapore.
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Small-molecule allosteric activators of PDE4 long form cyclic AMP phosphodiesterases. Proc Natl Acad Sci U S A 2019; 116:13320-13329. [PMID: 31209056 PMCID: PMC6613170 DOI: 10.1073/pnas.1822113116] [Citation(s) in RCA: 52] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Cyclic AMP (cAMP) phosphodiesterase-4 (PDE4) enzymes degrade cAMP and underpin the compartmentalization of cAMP signaling through their targeting to particular protein complexes and intracellular locales. We describe the discovery and characterization of a small-molecule compound that allosterically activates PDE4 long isoforms. This PDE4-specific activator displays reversible, noncompetitive kinetics of activation (increased V max with unchanged K m), phenocopies the ability of protein kinase A (PKA) to activate PDE4 long isoforms endogenously, and requires a dimeric enzyme assembly, as adopted by long, but not by short (monomeric), PDE4 isoforms. Abnormally elevated levels of cAMP provide a critical driver of the underpinning molecular pathology of autosomal dominant polycystic kidney disease (ADPKD) by promoting cyst formation that, ultimately, culminates in renal failure. Using both animal and human cell models of ADPKD, including ADPKD patient-derived primary cell cultures, we demonstrate that treatment with the prototypical PDE4 activator compound lowers intracellular cAMP levels, restrains cAMP-mediated signaling events, and profoundly inhibits cyst formation. PDE4 activator compounds thus have potential as therapeutics for treating disease driven by elevated cAMP signaling as well as providing a tool for evaluating the action of long PDE4 isoforms in regulating cAMP-mediated cellular processes.
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Yanda MK, Liu Q, Cebotaru V, Guggino WB, Cebotaru L. Role of calcium in adult onset polycystic kidney disease. Cell Signal 2019; 53:140-150. [PMID: 30296477 PMCID: PMC6347464 DOI: 10.1016/j.cellsig.2018.10.003] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2018] [Revised: 09/26/2018] [Accepted: 10/04/2018] [Indexed: 12/12/2022]
Abstract
Autosomal dominant polycystic kidney disease (ADPKD) is caused by mutations in genes encoding the polycystin (PC) 1 and 2 proteins. The goal of this study was to determine the role of calcium in regulating cyst growth. Stromal interaction molecule 1 (STIM1) protein expression was 15-fold higher in PC1-null proximal tubule cells (PN) than in heterozygote (PH) controls and 2-fold higher in an inducible, PC1 knockout, mouse model of ADPKD compared to a non-cystic match control. IP3 receptor protein expression was also higher in the cystic mice. Knocking down STIM1 with siRNA reduced cyst growth and lowered cAMP levels in PN cells. Fura2 measurements of intracellular Ca2+ showed higher levels of intracellular Ca2+, SOCE and thaspigargin-stimulated ER Ca2+ release in PN vs. PH cells. There was a dramatic reduction in thapsigargin-stimulated release of ER Ca2+ following STIM1 silencing or application of 2-APB, consistent with altered ER Ca2+ movement; the protein expression of the Ca2+-dependent adenylyl cyclases (AC) AC3 and AC6 was up- and down-regulated, respectively. Like STIM1 knockdown, application of the calmodulin inhibitor W7 lowered cAMP levels, further indicating that STIM1 regulates AC3 via Ca2+ We conclude that the high levels of STIM1 in ADPKD cells play a role in supporting cyst growth and promoting high cAMP levels and an increased release of Ca2+ from the ER. Thus, our results provide novel therapeutic targets for treating ADPKD.
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Affiliation(s)
- Murali K Yanda
- The Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Qiangni Liu
- The Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Valeriu Cebotaru
- University of Maryland School of Medicine, Baltimore, MD 21201, USA
| | | | - Liudmila Cebotaru
- The Johns Hopkins University School of Medicine, Baltimore, MD, USA.
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25
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Müller RU, Benzing T. Management of autosomal-dominant polycystic kidney disease-state-of-the-art. Clin Kidney J 2018; 11:i2-i13. [PMID: 30581561 PMCID: PMC6295602 DOI: 10.1093/ckj/sfy103] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2018] [Accepted: 09/12/2018] [Indexed: 02/07/2023] Open
Abstract
Autosomal-dominant polycystic kidney disease (ADPKD) is the most frequent genetic cause of end-stage renal disease in adults. Affected individuals and families face a significant medical and psychosocial burden due to both renal and extrarenal manifestations. Consequently, interventions that ameliorate the course of the disease and specifically slow down the loss of kidney function are of special interest. Major research efforts in both the clinical and pre-clinical setting in the last two decades resulted in a number of pivotal clinical trials aimed to ameliorate the disease. These studies have underlined the important role of specific supportive measures and provided the basis for first targeted pharmacological therapies. Very recently, the concept of repurposing drugs approved for other conditions for a use in ADPKD has gained increasing attention. Here, we review the current best-practice management of ADPKD patients with a focus on interventions that have reached clinical use to maintain kidney function and give an outlook on future trials and potential novel treatment strategies.
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Affiliation(s)
- Roman-Ulrich Müller
- Department II of Internal Medicine, Center for Molecular Medicine Cologne, University of Cologne, Germany.,Center for Rare and Hereditary Kidney Diseases, University of Cologne, Cologne, Germany
| | - Thomas Benzing
- Department II of Internal Medicine, Center for Molecular Medicine Cologne, University of Cologne, Germany.,Center for Rare and Hereditary Kidney Diseases, University of Cologne, Cologne, Germany
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26
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Leal-Esteban LC, Rothé B, Fortier S, Isenschmid M, Constam DB. Role of Bicaudal C1 in renal gluconeogenesis and its novel interaction with the CTLH complex. PLoS Genet 2018; 14:e1007487. [PMID: 29995892 PMCID: PMC6056059 DOI: 10.1371/journal.pgen.1007487] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2018] [Revised: 07/23/2018] [Accepted: 06/13/2018] [Indexed: 01/06/2023] Open
Abstract
Altered glucose and lipid metabolism fuel cystic growth in polycystic kidneys, but the cause of these perturbations is unclear. Renal cysts also associate with mutations in Bicaudal C1 (Bicc1) or in its self-polymerizing sterile alpha motif (SAM). Here, we found that Bicc1 maintains normoglycemia and the expression of the gluconeogenic enzymes FBP1 and PEPCK in kidneys. A proteomic screen revealed that Bicc1 interacts with the C-Terminal to Lis-Homology domain (CTLH) complex. Since the orthologous Gid complex in S. cerevisae targets FBP1 and PEPCK for degradation, we mapped the topology among CTLH subunits and found that SAM-mediated binding controls Bicc1 protein levels, whereas Bicc1 inhibited the accumulation of several CTLH subunits. Under the conditions analyzed, Bicc1 increased FBP1 protein levels independently of the CTLH complex. Besides linking Bicc1 to cell metabolism, our findings reveal new layers of complexity in the regulation of renal gluconeogenesis compared to lower eukaryotes. Polycystic kidney diseases (PKD) are incurable inherited chronic disorders marked by fluid-filled cysts that frequently cause renal failure. A glycolytic metabolism reminiscent of cancerous cells accelerates cystic growth, but the mechanism underlying such metabolic re-wiring is poorly understood. PKD-like cystic kidneys also develop in mice that lack the RNA-binding protein Bicaudal-C (Bicc1), and mutations in a single copy of human BICC1 associate with renal cystic dysplasia. Here, we report that Bicc1 regulates renal gluconeogenesis. A screen for interacting factors revealed that Bicc1 binds the C-Terminal to Lis-Homology domain (CTLH) complex, which in lower eukaryotes mediates degradation of gluconeogenic enzymes. By contrast, Bicc1 and the mammalian CTLH complex regulated each other, and Bicc1 stimulated the accumulation of the rate-limiting gluconeogenic enzyme even in cells depleted of CTLH subunits. Our finding that Bicc1 is required for normoglycemia implies that renal gluconeogenesis may be important to inhibit cyst formation.
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Affiliation(s)
- Lucia Carolina Leal-Esteban
- Ecole Polytechnique Fédérale de Lausanne (EPFL), School of Life Sciences, Swiss Institute for Experimental Cancer Research (ISREC), Lausanne, Switzerland
| | - Benjamin Rothé
- Ecole Polytechnique Fédérale de Lausanne (EPFL), School of Life Sciences, Swiss Institute for Experimental Cancer Research (ISREC), Lausanne, Switzerland
| | - Simon Fortier
- Ecole Polytechnique Fédérale de Lausanne (EPFL), School of Life Sciences, Swiss Institute for Experimental Cancer Research (ISREC), Lausanne, Switzerland
| | - Manuela Isenschmid
- Ecole Polytechnique Fédérale de Lausanne (EPFL), School of Life Sciences, Swiss Institute for Experimental Cancer Research (ISREC), Lausanne, Switzerland
| | - Daniel B. Constam
- Ecole Polytechnique Fédérale de Lausanne (EPFL), School of Life Sciences, Swiss Institute for Experimental Cancer Research (ISREC), Lausanne, Switzerland
- * E-mail:
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27
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Janssens P, Weydert C, De Rechter S, Wissing KM, Liebau MC, Mekahli D. Expanding the role of vasopressin antagonism in polycystic kidney diseases: From adults to children? Pediatr Nephrol 2018; 33:395-408. [PMID: 28455745 DOI: 10.1007/s00467-017-3672-x] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/08/2016] [Revised: 03/21/2017] [Accepted: 03/30/2017] [Indexed: 02/07/2023]
Abstract
Polycystic kidney disease (PKD) encompasses a group of genetic disorders that are common causes of renal failure. The two classic forms of PKD are autosomal recessive polycystic kidney disease (ARPKD) and autosomal dominant polycystic kidney disease (ADPKD). Despite their clinical differences, ARPKD and ADPKD share many similarities. Altered intracellular Ca2+ and increased cyclic adenosine monophosphate (cAMP) concentrations have repetitively been described as central anomalies that may alter signaling pathways leading to cyst formation. The vasopressin V2 receptor (V2R) antagonist tolvaptan lowers cAMP in cystic tissues and slows renal cystic progression and kidney function decline when given over 3 years in adult ADPKD patients. Tolvaptan is currently approved for the treatment of rapidly progressive disease in adult ADPKD patients. On the occasion of the recent initiation of a clinical trial with tolvaptan in pediatric ADPKD patients, we aim to describe the most important aspects in the literature regarding the AVP-cAMP axis and the clinical use of tolvaptan in PKD.
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Affiliation(s)
- Peter Janssens
- Laboratory of Pediatrics, University Hospitals Leuven, Leuven, Belgium. .,Department of Nephrology, University Hospitals Brussel, Brussel, Belgium.
| | - Caroline Weydert
- Laboratory of Pediatrics, University Hospitals Leuven, Leuven, Belgium
| | - Stephanie De Rechter
- Laboratory of Pediatrics, University Hospitals Leuven, Leuven, Belgium.,Department of Pediatric Nephrology, University Hospitals Leuven, Leuven, Belgium
| | | | - Max Christoph Liebau
- Pediatric Nephrology, Department of Pediatrics and Center for Molecular Medicine, University Hospital of Cologne, Cologne, Germany.,Department II of Internal Medicine, University Hospital of Cologne, Cologne, Germany.,Cologne Excellence Cluster on Cellular Stress Responses in Ageing-Associated Diseases (CECAD) and Systems Biology of Ageing Cologne (Sybacol), University of Cologne, Cologne, Germany
| | - Djalila Mekahli
- Laboratory of Pediatrics, University Hospitals Leuven, Leuven, Belgium.,Department of Pediatric Nephrology, University Hospitals Leuven, Leuven, Belgium
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28
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Park EYJ, Kwak M, Ha K, So I. Identification of clustered phosphorylation sites in PKD2L1: how PKD2L1 channel activation is regulated by cyclic adenosine monophosphate signaling pathway. Pflugers Arch 2017; 470:505-516. [PMID: 29230552 DOI: 10.1007/s00424-017-2095-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2017] [Revised: 11/21/2017] [Accepted: 12/01/2017] [Indexed: 01/01/2023]
Abstract
Polycystic kidney disease 2-like-1 (PKD2L1), or polycystin-L or TRPP2, formerly TRPP3, is a transient receptor potential (TRP) superfamily member. It is a calcium-permeable non-selective cation channel that regulates intracellular calcium concentration and thereby calcium signaling. PKD2L1 has been reported to take part in hedgehog signaling in renal primary cilia and sour tasting coupling with PKD1L3. In addition to the previous reports, PKD2L1 is recently found to play a crucial role in localization with β2-adrenergic receptor (β2AR) on the neuronal primary cilia. The disruption of PKD2L1 leads to the loss of β2AR on the primary cilia and reduction in intracellular concentration of cyclic adenosine monophosphate (cAMP). Since the role of cAMP and PKA is frequently mentioned in the studies of PKD diseases, we investigated on the mechanism of cAMP regulation in relation to the function of PKD2L1 channel. In this study, we observed the activity of PKD2L1 channel increased by the downstream cascades of β2AR and found the clustered phosphorylation sites, Ser-682, Ser-685, and Ser-686 that are significant in the channel regulation by phosphorylation.
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Affiliation(s)
- Eunice Yon June Park
- Department of Physiology, Seoul National University, College of Medicine, Biomedical Science Building 117, 103 Daehakro, Jongro-gu, Seoul, 110-799, South Korea
| | - Misun Kwak
- Department of Physiology, Seoul National University, College of Medicine, Biomedical Science Building 117, 103 Daehakro, Jongro-gu, Seoul, 110-799, South Korea
| | - Kotdaji Ha
- Department of Physiology, University of California, San Francisco, CA, 94158-2517, USA
| | - Insuk So
- Department of Physiology, Seoul National University, College of Medicine, Biomedical Science Building 117, 103 Daehakro, Jongro-gu, Seoul, 110-799, South Korea.
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29
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Ma M, Gallagher AR, Somlo S. Ciliary Mechanisms of Cyst Formation in Polycystic Kidney Disease. Cold Spring Harb Perspect Biol 2017; 9:a028209. [PMID: 28320755 PMCID: PMC5666631 DOI: 10.1101/cshperspect.a028209] [Citation(s) in RCA: 86] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Autosomal-dominant polycystic kidney disease (ADPKD) is a disease of defective tissue homeostasis resulting in active remodeling of nephrons and bile ducts to form fluid-filled sacs called cysts. The causal genes PKD1 and PKD2 encode transmembrane proteins polycystin 1 (PC1) and polycystin 2 (PC2), respectively. Together, the polycystins localize to the solitary primary cilium that protrudes from the apical surface of most kidney tubule cells and is thought to function as a privileged compartment that the cell uses for signal integration of sensory inputs. It has been proposed that PC1 and PC2 form a receptor-channel complex that detects external stimuli and transmit a local calcium-mediated signal, which may control a multitude of cellular processes by an as-yet unknown mechanism. Genetic studies using mouse models of cilia and polycystin dysfunction have shown that polycystins regulate an unknown cilia-dependent signal that is normally part of the homeostatic maintenance of nephron structure. ADPKD ensues when this pathway is dysregulated by absence of polycystins from intact cilia, but disruption of cilia also disrupts this signaling mechanism and ameliorates ADPKD even in the absence of polycystins. Understanding the role of cilia and ciliary signaling in ADPKD is challenging, but success will provide saltatory advances in our understanding of how tubule structure is maintained in healthy kidneys and how disruption of polycystin or cilia function leads to the pathological tissue remodeling process underlying ADPKD.
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Affiliation(s)
- Ming Ma
- Department of Internal Medicine, Yale University School of Medicine, New Haven, Connecticut 06520-8029
| | - Anna-Rachel Gallagher
- Department of Internal Medicine, Yale University School of Medicine, New Haven, Connecticut 06520-8029
| | - Stefan Somlo
- Department of Internal Medicine, Yale University School of Medicine, New Haven, Connecticut 06520-8029
- Department of Genetics, Yale University School of Medicine, New Haven, Connecticut 06520-8029
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30
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Adenylyl cyclase 5 deficiency reduces renal cyclic AMP and cyst growth in an orthologous mouse model of polycystic kidney disease. Kidney Int 2017; 93:403-415. [PMID: 29042084 DOI: 10.1016/j.kint.2017.08.005] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2017] [Revised: 07/24/2017] [Accepted: 08/03/2017] [Indexed: 11/22/2022]
Abstract
Cyclic AMP promotes cyst growth in polycystic kidney disease (PKD) by stimulating cell proliferation and fluid secretion. Previously, we showed that the primary cilium of renal epithelial cells contains a cAMP regulatory complex comprising adenylyl cyclases 5 and 6 (AC5/6), polycystin-2, A-kinase anchoring protein 150, protein kinase A, and phosphodiesterase 4C. In Kif3a mutant cells that lack primary cilia, the formation of this regulatory complex is disrupted and cAMP levels are increased. Inhibition of AC5 reduces cAMP levels in Kif3a mutant cells, suggesting that AC5 may mediate the increase in cAMP in PKD. Here, we examined the role of AC5 in an orthologous mouse model of PKD caused by kidney-specific ablation of Pkd2. Knockdown of AC5 with siRNA attenuated the increase in cAMP levels in Pkd2-deficient renal epithelial cells. Levels of cAMP and AC5 mRNA transcripts were elevated in the kidneys of mice with collecting duct-specific ablation of Pkd2. Compared with Pkd2 single mutant mice, AC5/Pkd2 double mutant mice had less kidney enlargement, lower cyst index, reduced kidney injury, and improved kidney function. Importantly, cAMP levels and cAMP-dependent signaling were reduced in the kidneys of AC5/Pkd2 double mutant compared to the kidneys of Pkd2 single mutant mice. Additionally, we localized endogenous AC5 in the primary cilium of renal epithelial cells and showed that ablation of AC5 reduced ciliary elongation in the kidneys of Pkd2 mutant mice. Thus, AC5 contributes importantly to increased renal cAMP levels and cyst growth in Pkd2 mutant mice, and inhibition of AC5 may be beneficial in the treatment of PKD.
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31
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Clark WF, Devuyst O, Roussel R. The vasopressin system: new insights for patients with kidney diseases: Epidemiological evidence and therapeutic perspectives. J Intern Med 2017; 282:310-321. [PMID: 28905441 DOI: 10.1111/joim.12654] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
People with chronic kidney disease (CKD) are at risk of severe outcomes, such as end-stage renal disease or cardiovascular disease, and CKD is a globally increasing health burden with a high personal and economic cost. Despite major progresses in prevention and therapeutics in last decades, research is still needed to reverse this epidemic trend. The regulation of water balance and the state of activation of the vasopressin system have emerged as factors tightly associated with kidney health, in the general population but also in specific conditions; among them, various stages of CKD, diabetes and autosomal dominant polycystic kidney disease (ADPKD). Basic science findings and also epidemiological evidence have justified important efforts towards interventional studies supporting causality, and opening therapeutic avenues. On the basis of recent clinical data, the blockade of V2 vasopressin receptors using tolvaptan in patients with rapidly progressing ADPKD has been granted in several countries, and a long-term randomized trial evaluating the effect of an increase in water intake in patients with CKD is on-going.
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Affiliation(s)
- W F Clark
- Division of Nephrology, Department of Medicine, London Health Sciences Centre, London, ON, Canada
| | - O Devuyst
- Institute of Physiology, University of Zurich, Zurich, Switzerland
| | - R Roussel
- INSERM, UMR_S 1138, Centre de Recherche des Cordeliers, Paris, France.,Département de Diabétologie, Endocrinologie et Nutrition, Assistance Publique Hôpitaux de Paris, Hôpital Bichat, DHU FIRE, Paris, France.,Sorbonne Paris Cite, UFR de Médecine, Université Paris Diderot, Paris, France
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32
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Yanda MK, Liu Q, Cebotaru V, Guggino WB, Cebotaru L. Histone deacetylase 6 inhibition reduces cysts by decreasing cAMP and Ca 2+ in knock-out mouse models of polycystic kidney disease. J Biol Chem 2017; 292:17897-17908. [PMID: 28887310 DOI: 10.1074/jbc.m117.803775] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2017] [Revised: 08/31/2017] [Indexed: 11/06/2022] Open
Abstract
Autosomal dominant polycystic kidney disease (ADPKD) is associated with progressive enlargement of multiple renal cysts, often leading to renal failure that cannot be prevented by a current treatment. Two proteins encoded by two genes are associated with ADPKD: PC1 (pkd1), primarily a signaling molecule, and PC2 (pkd2), a Ca2+ channel. Dysregulation of cAMP signaling is central to ADPKD, but the molecular mechanism is unresolved. Here, we studied the role of histone deacetylase 6 (HDAC6) in regulating cyst growth to test the possibility that inhibiting HDAC6 might help manage ADPKD. Chemical inhibition of HDAC6 reduced cyst growth in PC1-knock-out mice. In proximal tubule-derived, PC1-knock-out cells, adenylyl cyclase 6 and 3 (AC6 and -3) are both expressed. AC6 protein expression was higher in cells lacking PC1, compared with control cells containing PC1. Intracellular Ca2+ was higher in PC1-knock-out cells than in control cells. HDAC inhibition caused a drop in intracellular Ca2+ and increased ATP-simulated Ca2+ release. HDAC6 inhibition reduced the release of Ca2+ from the endoplasmic reticulum induced by thapsigargin, an inhibitor of endoplasmic reticulum Ca2+-ATPase. HDAC6 inhibition and treatment of cells with the intracellular Ca2+ chelator 1,2-bis(2-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid tetrakis(acetoxymethyl ester) reduced cAMP levels in PC1-knock-out cells. Finally, the calmodulin inhibitors W-7 and W-13 reduced cAMP levels, and W-7 reduced cyst growth, suggesting that AC3 is involved in cyst growth regulated by HDAC6. We conclude that HDAC6 inhibition reduces cell growth primarily by reducing intracellular cAMP and Ca2+ levels. Our results provide potential therapeutic targets that may be useful as treatments for ADPKD.
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Affiliation(s)
- Murali K Yanda
- From the Division of Gastroenterology and Hepatology, Department of Medicine, The Johns Hopkins University School of Medicine, Baltimore, Maryland 21205 and
| | - Qiangni Liu
- From the Division of Gastroenterology and Hepatology, Department of Medicine, The Johns Hopkins University School of Medicine, Baltimore, Maryland 21205 and
| | - Valeriu Cebotaru
- the Department of Medicine, University of Maryland School of Medicine, Baltimore, Maryland 21201
| | - William B Guggino
- From the Division of Gastroenterology and Hepatology, Department of Medicine, The Johns Hopkins University School of Medicine, Baltimore, Maryland 21205 and
| | - Liudmila Cebotaru
- From the Division of Gastroenterology and Hepatology, Department of Medicine, The Johns Hopkins University School of Medicine, Baltimore, Maryland 21205 and
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33
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Wang X, Yamada S, LaRiviere WB, Ye H, Bakeberg JL, Irazabal MV, Chebib FT, van Deursen J, Harris PC, Sussman CR, Behfar A, Ward CJ, Torres VE. Generation and phenotypic characterization of Pde1a mutant mice. PLoS One 2017; 12:e0181087. [PMID: 28750036 PMCID: PMC5531505 DOI: 10.1371/journal.pone.0181087] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2017] [Accepted: 06/26/2017] [Indexed: 12/15/2022] Open
Abstract
It has been proposed that a reduction in intracellular calcium causes an increase in intracellular cAMP and PKA activity through stimulation of calcium inhibitable adenylyl cyclase 6 and inhibition of phosphodiesterase 1 (PDE1), the main enzymes generating and degrading cAMP in the distal nephron and collecting duct, thus contributing to the development and progression of autosomal dominant polycystic kidney disease (ADPKD). In zebrafish pde1a depletion aggravates and overexpression ameliorates the cystic phenotype. To study the role of PDE1A in a mammalian system, we used a TALEN pair to Pde1a exon 7, targeting the histidine-aspartic acid dipeptide involved in ligating the active site Zn++ ion to generate two Pde1a null mouse lines. Pde1a mutants had a mild renal cystic disease and a urine concentrating defect (associated with upregulation of PDE4 activity and decreased protein kinase A dependent phosphorylation of aquaporin-2) on a wild-type genetic background and aggravated renal cystic disease on a Pkd2WS25/- background. Pde1a mutants additionally had lower aortic blood pressure and increased left ventricular (LV) ejection fraction, without a change in LV mass index, consistent with the high aortic and low cardiac expression of Pde1a in wild-type mice. These results support an important role of PDE1A in the renal pathogenesis of ADPKD and in the regulation of blood pressure.
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Affiliation(s)
- Xiaofang Wang
- Division of Nephrology and Hypertension, Mayo Clinic, Rochester, Minnesota, United States of America
| | - Satsuki Yamada
- Department of Cardiovascular Diseases, Mayo Clinic, Rochester, Minnesota, United States of America
| | - Wells B. LaRiviere
- Division of Nephrology and Hypertension, Mayo Clinic, Rochester, Minnesota, United States of America
| | - Hong Ye
- Division of Nephrology and Hypertension, Mayo Clinic, Rochester, Minnesota, United States of America
| | - Jason L. Bakeberg
- Division of Nephrology and Hypertension, University of Kansas Medical Center, Kansas City, Kansas, United States of America
| | - María V. Irazabal
- Division of Nephrology and Hypertension, Mayo Clinic, Rochester, Minnesota, United States of America
| | - Fouad T. Chebib
- Division of Nephrology and Hypertension, Mayo Clinic, Rochester, Minnesota, United States of America
| | - Jan van Deursen
- Department of Biochemistry and Molecular Biology, Mayo Clinic, Rochester, Minnesota, United States of America
| | - Peter C. Harris
- Division of Nephrology and Hypertension, Mayo Clinic, Rochester, Minnesota, United States of America
- Department of Biochemistry and Molecular Biology, Mayo Clinic, Rochester, Minnesota, United States of America
| | - Caroline R. Sussman
- Division of Nephrology and Hypertension, Mayo Clinic, Rochester, Minnesota, United States of America
| | - Atta Behfar
- Department of Cardiovascular Diseases, Mayo Clinic, Rochester, Minnesota, United States of America
| | - Christopher J. Ward
- Division of Nephrology and Hypertension, University of Kansas Medical Center, Kansas City, Kansas, United States of America
- * E-mail: (VET); (CJW)
| | - Vicente E. Torres
- Division of Nephrology and Hypertension, Mayo Clinic, Rochester, Minnesota, United States of America
- * E-mail: (VET); (CJW)
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Yanda MK, Liu Q, Cebotaru L. An inhibitor of histone deacetylase 6 activity, ACY-1215, reduces cAMP and cyst growth in polycystic kidney disease. Am J Physiol Renal Physiol 2017; 313:F997-F1004. [PMID: 28747357 DOI: 10.1152/ajprenal.00186.2017] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2017] [Revised: 06/26/2017] [Accepted: 07/17/2017] [Indexed: 11/22/2022] Open
Abstract
Adult-onset autosomal-dominant polycystic kidney disease (ADPKD) is caused by mutations in either the PKD1 or PKD2 gene, leading to malfunction of their gene products, polycystin 1 or 2. Histone deacetylase 6 (HDAC6) expression and activity are increased in PKD1 mutant renal epithelial cells. Here we studied the effect of ACY-1215, a specific HDAC6 inhibitor, on cyst growth in ADPKD. Treatment with ACY-1215 slowed cyst growth in a mouse model of ADPKD that forms massive cysts within 3 wk after knockout of polycystin 1 function. It also prevented cyst formation in MDCK.2 cells, an in vitro model of cystogenesis, and in an ADPKD cell line derived from the proximal tubules from a pkd1-/-.mouse (PN cells). In PN cells ACY-1215 also reduced the size of already established cysts. We found that ACY-1215 lowered cAMP levels and protein expression of adenylyl cyclase 6. Our results suggest that HDAC6 could potentially serve as a therapeutic target in ADPKD.
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Affiliation(s)
- Murali K Yanda
- Department of Medicine, The Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Qiangni Liu
- Department of Medicine, The Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Liudmila Cebotaru
- Department of Medicine, The Johns Hopkins University School of Medicine, Baltimore, Maryland
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Ye H, Wang X, Constans MM, Sussman CR, Chebib FT, Irazabal MV, Young WF, Harris PC, Kirschner LS, Torres VE. The regulatory 1α subunit of protein kinase A modulates renal cystogenesis. Am J Physiol Renal Physiol 2017; 313:F677-F686. [PMID: 28615245 DOI: 10.1152/ajprenal.00119.2017] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2017] [Revised: 06/09/2017] [Accepted: 06/12/2017] [Indexed: 11/22/2022] Open
Abstract
The failure of the polycystins (PCs) to function in primary cilia is thought to be responsible for autosomal dominant polycystic kidney disease (ADPKD). Primary cilia integrate multiple cellular signaling pathways, including calcium, cAMP, Wnt, and Hedgehog, which control cell proliferation and differentiation. It has been proposed that mutated PCs result in reduced intracellular calcium, which in turn upregulates cAMP, protein kinase A (PKA) signaling, and subsequently other proliferative signaling pathways. However, the role of PKA in ADPKD has not been directly ascertained in vivo, although the expression of the main regulatory subunit of PKA in cilia and other compartments (PKA-RIα, encoded by PRKAR1A) is increased in a mouse model orthologous to ADPKD. Therefore, we generated a kidney-specific knockout of Prkar1a to examine the consequences of constitutive upregulation of PKA on wild-type and Pkd1 hypomorphic (Pkd1RC) backgrounds. Kidney-specific loss of Prkar1a induced renal cystic disease and markedly aggravated cystogenesis in the Pkd1RC models. In both settings, it was accompanied by upregulation of Src, Ras, MAPK/ERK, mTOR, CREB, STAT3, Pax2 and Wnt signaling. On the other hand, Gli3 repressor activity was enhanced, possibly contributing to hydronephrosis and impaired glomerulogenesis in some animals. To assess the relevance of these observations in humans we looked for and found evidence for kidney and liver cystic phenotypes in the Carney complex, a tumoral syndrome caused by mutations in PRKAR1A These observations expand our understanding of the pathogenesis of ADPKD and demonstrate the importance of PRKAR1A highlighting PKA as a therapeutic target in ADPKD.
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Affiliation(s)
- Hong Ye
- Mayo Clinic, Rochester Minnesota; and
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36
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Lemos FO, Ehrlich BE. Polycystin and calcium signaling in cell death and survival. Cell Calcium 2017; 69:37-45. [PMID: 28601384 DOI: 10.1016/j.ceca.2017.05.011] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2017] [Revised: 05/18/2017] [Accepted: 05/19/2017] [Indexed: 12/19/2022]
Abstract
Mutations in polycystin-1 (PC1) and polycystin-2 (PC2) result in a commonly occurring genetic disorder, called Autosomal Dominant Polycystic Kidney Disease (ADPKD), that is characterized by the formation and development of kidney cysts. Epithelial cells with loss-of-function of PC1 or PC2 show higher rates of proliferation and apoptosis and reduced autophagy. PC1 is a large multifunctional transmembrane protein that serves as a sensor that is usually found in complex with PC2, a calcium (Ca2+)-permeable cation channel. In addition to decreased Ca2+ signaling, several other cell fate-related pathways are de-regulated in ADPKD, including cAMP, MAPK, Wnt, JAK-STAT, Hippo, Src, and mTOR. In this review we discuss how polycystins regulate cell death and survival, highlighting the complexity of molecular cascades that are involved in ADPKD.
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Affiliation(s)
- Fernanda O Lemos
- Department of Pharmacology, Yale University, 333 Cedar St, New Haven, CT, 06520, USA
| | - Barbara E Ehrlich
- Department of Pharmacology, Yale University, 333 Cedar St, New Haven, CT, 06520, USA; Department of Cellular and Molecular Physiology, Yale University, 333 Cedar St, New Haven, CT, 06520, USA.
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37
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Dessauer CW, Watts VJ, Ostrom RS, Conti M, Dove S, Seifert R. International Union of Basic and Clinical Pharmacology. CI. Structures and Small Molecule Modulators of Mammalian Adenylyl Cyclases. Pharmacol Rev 2017; 69:93-139. [PMID: 28255005 PMCID: PMC5394921 DOI: 10.1124/pr.116.013078] [Citation(s) in RCA: 128] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Adenylyl cyclases (ACs) generate the second messenger cAMP from ATP. Mammalian cells express nine transmembrane AC (mAC) isoforms (AC1-9) and a soluble AC (sAC, also referred to as AC10). This review will largely focus on mACs. mACs are activated by the G-protein Gαs and regulated by multiple mechanisms. mACs are differentially expressed in tissues and regulate numerous and diverse cell functions. mACs localize in distinct membrane compartments and form signaling complexes. sAC is activated by bicarbonate with physiologic roles first described in testis. Crystal structures of the catalytic core of a hybrid mAC and sAC are available. These structures provide detailed insights into the catalytic mechanism and constitute the basis for the development of isoform-selective activators and inhibitors. Although potent competitive and noncompetitive mAC inhibitors are available, it is challenging to obtain compounds with high isoform selectivity due to the conservation of the catalytic core. Accordingly, caution must be exerted with the interpretation of intact-cell studies. The development of isoform-selective activators, the plant diterpene forskolin being the starting compound, has been equally challenging. There is no known endogenous ligand for the forskolin binding site. Recently, development of selective sAC inhibitors was reported. An emerging field is the association of AC gene polymorphisms with human diseases. For example, mutations in the AC5 gene (ADCY5) cause hyperkinetic extrapyramidal motor disorders. Overall, in contrast to the guanylyl cyclase field, our understanding of the (patho)physiology of AC isoforms and the development of clinically useful drugs targeting ACs is still in its infancy.
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Affiliation(s)
- Carmen W Dessauer
- Department of Integrative Biology and Pharmacology, McGovern Medical School, The University of Texas Health Sciences Center at Houston, Houston, Texas (C.W.D.); Department of Medicinal Chemistry and Molecular Pharmacology, Purdue University, West Lafayette, Indiana (V.J.W.); Department of Biomedical and Pharmaceutical Sciences, Chapman University School of Pharmacy, Irvine, California (R.S.O.); Center for Reproductive Sciences, University of California San Francisco, San Francisco, California (M.C.); Institute of Pharmacy, University of Regensburg, Regensburg, Germany (S.D.); and Institute of Pharmacology, Hannover Medical School, Hannover, Germany (R.S.)
| | - Val J Watts
- Department of Integrative Biology and Pharmacology, McGovern Medical School, The University of Texas Health Sciences Center at Houston, Houston, Texas (C.W.D.); Department of Medicinal Chemistry and Molecular Pharmacology, Purdue University, West Lafayette, Indiana (V.J.W.); Department of Biomedical and Pharmaceutical Sciences, Chapman University School of Pharmacy, Irvine, California (R.S.O.); Center for Reproductive Sciences, University of California San Francisco, San Francisco, California (M.C.); Institute of Pharmacy, University of Regensburg, Regensburg, Germany (S.D.); and Institute of Pharmacology, Hannover Medical School, Hannover, Germany (R.S.)
| | - Rennolds S Ostrom
- Department of Integrative Biology and Pharmacology, McGovern Medical School, The University of Texas Health Sciences Center at Houston, Houston, Texas (C.W.D.); Department of Medicinal Chemistry and Molecular Pharmacology, Purdue University, West Lafayette, Indiana (V.J.W.); Department of Biomedical and Pharmaceutical Sciences, Chapman University School of Pharmacy, Irvine, California (R.S.O.); Center for Reproductive Sciences, University of California San Francisco, San Francisco, California (M.C.); Institute of Pharmacy, University of Regensburg, Regensburg, Germany (S.D.); and Institute of Pharmacology, Hannover Medical School, Hannover, Germany (R.S.)
| | - Marco Conti
- Department of Integrative Biology and Pharmacology, McGovern Medical School, The University of Texas Health Sciences Center at Houston, Houston, Texas (C.W.D.); Department of Medicinal Chemistry and Molecular Pharmacology, Purdue University, West Lafayette, Indiana (V.J.W.); Department of Biomedical and Pharmaceutical Sciences, Chapman University School of Pharmacy, Irvine, California (R.S.O.); Center for Reproductive Sciences, University of California San Francisco, San Francisco, California (M.C.); Institute of Pharmacy, University of Regensburg, Regensburg, Germany (S.D.); and Institute of Pharmacology, Hannover Medical School, Hannover, Germany (R.S.)
| | - Stefan Dove
- Department of Integrative Biology and Pharmacology, McGovern Medical School, The University of Texas Health Sciences Center at Houston, Houston, Texas (C.W.D.); Department of Medicinal Chemistry and Molecular Pharmacology, Purdue University, West Lafayette, Indiana (V.J.W.); Department of Biomedical and Pharmaceutical Sciences, Chapman University School of Pharmacy, Irvine, California (R.S.O.); Center for Reproductive Sciences, University of California San Francisco, San Francisco, California (M.C.); Institute of Pharmacy, University of Regensburg, Regensburg, Germany (S.D.); and Institute of Pharmacology, Hannover Medical School, Hannover, Germany (R.S.)
| | - Roland Seifert
- Department of Integrative Biology and Pharmacology, McGovern Medical School, The University of Texas Health Sciences Center at Houston, Houston, Texas (C.W.D.); Department of Medicinal Chemistry and Molecular Pharmacology, Purdue University, West Lafayette, Indiana (V.J.W.); Department of Biomedical and Pharmaceutical Sciences, Chapman University School of Pharmacy, Irvine, California (R.S.O.); Center for Reproductive Sciences, University of California San Francisco, San Francisco, California (M.C.); Institute of Pharmacy, University of Regensburg, Regensburg, Germany (S.D.); and Institute of Pharmacology, Hannover Medical School, Hannover, Germany (R.S.)
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38
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Abstract
Autosomal dominant polycystic kidney disease (ADPKD) is a signalopathy of renal tubular epithelial cells caused by naturally occurring mutations in two distinct genes, polycystic kidney disease 1 (PKD1) and 2 (PKD2). Genetic variants in PKD1, which encodes the polycystin-1 (PC-1) protein, remain the predominant factor associated with the pathogenesis of nearly two-thirds of all patients diagnosed with PKD. Although the relationship between defective PC-1 with renal cystic disease initiation and progression remains to be fully elucidated, there are numerous clinical studies that have focused upon the control of effector systems involving heterotrimeric G protein regulation. A major regulator in the activation state of heterotrimeric G proteins are G protein-coupled receptors (GPCRs), which are defined by their seven transmembrane-spanning regions. PC-1 has been considered to function as an unconventional GPCR, but the mechanisms by which PC-1 controls signal processing, magnitude, or trafficking through heterotrimeric G proteins remains to be fully known. The diversity of heterotrimeric G protein signaling in PKD is further complicated by the presence of non-GPCR proteins in the membrane or cytoplasm that also modulate the functional state of heterotrimeric G proteins within the cell. Moreover, PC-1 abnormalities promote changes in hormonal systems that ultimately interact with distinct GPCRs in the kidney to potentially amplify or antagonize signaling output from PC-1. This review will focus upon the canonical and noncanonical signaling pathways that have been described in PKD with specific emphasis on which heterotrimeric G proteins are involved in the pathological reorganization of the tubular epithelial cell architecture to exacerbate renal cystogenic pathways.
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Affiliation(s)
- Taketsugu Hama
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Tennessee Health Science Center, Memphis, Tennessee
| | - Frank Park
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Tennessee Health Science Center, Memphis, Tennessee
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Ye H, Wang X, Sussman CR, Hopp K, Irazabal MV, Bakeberg JL, LaRiviere WB, Manganiello VC, Vorhees CV, Zhao H, Harris PC, van Deursen J, Ward CJ, Torres VE. Modulation of Polycystic Kidney Disease Severity by Phosphodiesterase 1 and 3 Subfamilies. J Am Soc Nephrol 2016; 27:1312-20. [PMID: 26374610 PMCID: PMC4849815 DOI: 10.1681/asn.2015010057] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2015] [Accepted: 08/04/2015] [Indexed: 11/03/2022] Open
Abstract
Aberrant intracellular calcium levels and increased cAMP signaling contribute to the development of polycystic kidney disease (PKD). cAMP can be hydrolyzed by various phosphodiesterases (PDEs). To examine the role of cAMP hydrolysis and the most relevant PDEs in the pathogenesis of PKD, we examined cyst development in Pde1- or Pde3-knockout mice on the Pkd2(-/WS25) background (WS25 is an unstable Pkd2 allele). These PDEs were selected because of their importance in cross-talk between calcium and cyclic nucleotide signaling (PDE1), control of cell proliferation and cystic fibrosis transmembrane conductance regulator (CFTR) -driven fluid secretion (PDE3), and response to vasopressin V2 receptor activation (both). In Pkd2(-/WS25) mice, knockout of Pde1a, Pde1c, or Pde3a but not of Pde1b or Pde3b aggravated the development of PKD and was associated with higher levels of protein kinase A-phosphorylated (Ser133) cAMP-responsive binding protein (P-CREB), activating transcription factor-1, and CREB-induced CRE modulator proteins in kidney nuclear preparations. Immunostaining also revealed higher expression of P-CREB in Pkd2(-/) (WS25);Pde1a(-/-), Pkd2(-) (/WS25);Pde1c(-/-), and Pkd2(-/) (WS25);Pde3a(-/-) kidneys. The cystogenic effect of desmopressin administration was markedly enhanced in Pkd2(-/WS25);Pde3a(-/-) mice, despite PDE3 accounting for only a small fraction of renal cAMP PDE activity. These observations show that calcium- and calmodulin-dependent PDEs (PDE1A and PDE1C) and PDE3A modulate the development of PKD, possibly through the regulation of compartmentalized cAMP pools that control cell proliferation and CFTR-driven fluid secretion. Treatments capable of increasing the expression or activity of these PDEs may, therefore, retard the development of PKD.
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Affiliation(s)
- Hong Ye
- Division of Nephrology and Hypertension and
| | | | | | | | | | - Jason L Bakeberg
- Division of Nephrology and Hypertension, The Kidney Institute, University of Kansas Medical Center, Kansas City, Kansas
| | | | - Vincent C Manganiello
- Cardiovascular and Pulmonary Branch, National Heart, Lung and Blood Institute, US National Institutes of Health, Bethesda, Maryland
| | - Charles V Vorhees
- Department of Pediatrics, Division of Neurology, Cincinnati Children's Research Foundation and University of Cincinnati, Cincinnati, Ohio; and
| | - Haiqing Zhao
- Department of Biology, Johns Hopkins University, Baltimore, Maryland
| | | | - Jan van Deursen
- Department of Biochemistry and Molecular Biology, Mayo Clinic, Rochester, Minnesota
| | - Christopher J Ward
- Division of Nephrology and Hypertension, The Kidney Institute, University of Kansas Medical Center, Kansas City, Kansas
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Mangolini A, de Stephanis L, Aguiari G. Role of calcium in polycystic kidney disease: From signaling to pathology. World J Nephrol 2016; 5:76-83. [PMID: 26788466 PMCID: PMC4707171 DOI: 10.5527/wjn.v5.i1.76] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/09/2015] [Revised: 10/21/2015] [Accepted: 12/11/2015] [Indexed: 02/06/2023] Open
Abstract
Autosomal dominant polycystic kidney disease (ADPKD) is the most common inherited monogenic kidney disease. Characterized by the development and growth of cysts that cause progressive kidney enlargement, it ultimately leads to end-stage renal disease. Approximately 85% of ADPKD cases are caused by mutations in the PKD1 gene, while mutations in the PKD2 gene account for the remaining 15% of cases. The PKD1 gene encodes for polycystin-1 (PC1), a large multi-functional membrane receptor protein able to regulate ion channel complexes, whereas polycystin-2 (PC2), encoded by the PKD2 gene, is an integral membrane protein that functions as a calcium-permeable cation channel, located mainly in the endoplasmic reticulum (ER). In the primary cilia of the epithelial cells, PC1 interacts with PC2 to form a polycystin complex that acts as a mechanosensor, regulating signaling pathways involved in the differentiation of kidney tubular epithelial cells. Despite progress in understanding the function of these proteins, the molecular mechanisms associated with the pathogenesis of ADPKD remain unclear. In this review we discuss how an imbalance between functional PC1 and PC2 proteins may disrupt calcium channel activities in the cilium, plasma membrane and ER, thereby altering intracellular calcium signaling and leading to the aberrant cell proliferation and apoptosis associated with the development and growth of renal cysts. Research in this field could lead to the discovery of new molecules able to rebalance intracellular calcium, thereby normalizing cell proliferation and reducing kidney cyst progression.
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Ouabain rescues rat nephrogenesis during intrauterine growth restriction by regulating the complement and coagulation cascades and calcium signaling pathway. J Dev Orig Health Dis 2015; 7:91-101. [PMID: 26442628 DOI: 10.1017/s2040174415007242] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Intrauterine growth restriction (IUGR) is associated with a reduction in the numbers of nephrons in neonates, which increases the risk of hypertension. Our previous study showed that ouabain protects the development of the embryonic kidney during IUGR. To explore this molecular mechanism, IUGR rats were induced by protein and calorie restriction throughout pregnancy, and ouabain was delivered using a mini osmotic pump. RNA sequencing technology was used to identify the differentially expressed genes (DEGs) of the embryonic kidneys. DEGs were submitted to the Database for Annotation and Visualization and Integrated Discovery, and gene ontology enrichment analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis were conducted. Maternal malnutrition significantly reduced fetal weight, but ouabain treatment had no significant effect on body weight. A total of 322 (177 upregulated and 145 downregulated) DEGs were detected between control and the IUGR group. Meanwhile, 318 DEGs were found to be differentially expressed (180 increased and 138 decreased) between the IUGR group and the ouabain-treated group. KEGG pathway analysis indicated that maternal undernutrition mainly disrupts the complement and coagulation cascades and the calcium signaling pathway, which could be protected by ouabain treatment. Taken together, these two biological pathways may play an important role in nephrogenesis, indicating potential novel therapeutic targets against the unfavorable effects of IUGR.
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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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Abstract
Loss of the RNA-binding protein Bicaudal-C (Bicc1) provokes renal and pancreatic cysts as well as ectopic Wnt/β-catenin signaling during visceral left-right patterning. Renal cysts are linked to defective silencing of Bicc1 target mRNAs, including adenylate cyclase 6 (AC6). RNA binding of Bicc1 is mediated by N-terminal KH domains, whereas a C-terminal sterile alpha motif (SAM) self-polymerizes in vitro and localizes Bicc1 in cytoplasmic foci in vivo. To assess a role for multimerization in silencing, we conducted structure modeling and then mutated the SAM domain residues which in this model were predicted to polymerize Bicc1 in a left-handed helix. We show that a SAM-SAM interface concentrates Bicc1 in cytoplasmic clusters to specifically localize and silence bound mRNA. In addition, defective polymerization decreases Bicc1 stability and thus indirectly attenuates inhibition of Dishevelled 2 in the Wnt/β-catenin pathway. Importantly, aberrant C-terminal extension of the SAM domain in bpk mutant Bicc1 phenocopied these defects. We conclude that polymerization is a novel disease-relevant mechanism both to stabilize Bicc1 and to present associated mRNAs in specific silencing platforms.
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44
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Ong ACM, Devuyst O, Knebelmann B, Walz G. Autosomal dominant polycystic kidney disease: the changing face of clinical management. Lancet 2015; 385:1993-2002. [PMID: 26090645 DOI: 10.1016/s0140-6736(15)60907-2] [Citation(s) in RCA: 202] [Impact Index Per Article: 22.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Autosomal dominant polycystic kidney disease is the most common inherited kidney disease and accounts for 7-10% of all patients on renal replacement therapy worldwide. Although first reported 500 years ago, this disorder is still regarded as untreatable and its pathogenesis is poorly understood despite much study. During the past 40 years, however, remarkable advances have transformed our understanding of how the disease develops and have led to rapid changes in diagnosis, prognosis, and treatment, especially during the past decade. This Review will summarise the key findings, highlight recent developments, and look ahead to the changes in clinical practice that will likely arise from the adoption of a new management framework for this major kidney disease.
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Affiliation(s)
- Albert C M Ong
- Academic Nephrology Unit, University of Sheffield Medical School, Sheffield, UK; Sheffield Kidney Institute, Sheffield Teaching Hospitals NHS Foundation Trust, Sheffield, UK.
| | - Olivier Devuyst
- Institute of Physiology, Zurich Center for Integrative Human Physiology, University of Zurich, Zurich, Switzerland; Division of Nephrology, Université catholique de Louvain, Brussels, Belgium
| | - Bertrand Knebelmann
- Centre de Reference Maladies Rénales Héréditaires MARHEA, AP-HP, Hopital Necker, Université Paris Descartes, Paris, France
| | - Gerd Walz
- Department of Nephrology, University Freiburg Medical Center, Freiburg, Germany
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Lemaire LA, Goulley J, Kim YH, Carat S, Jacquemin P, Rougemont J, Constam DB, Grapin-Botton A. Bicaudal C1 promotes pancreatic NEUROG3+ endocrine progenitor differentiation and ductal morphogenesis. Development 2015; 142:858-70. [PMID: 25715394 DOI: 10.1242/dev.114611] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
In human, mutations in bicaudal C1 (BICC1), an RNA binding protein, have been identified in patients with kidney dysplasia. Deletion of Bicc1 in mouse leads to left-right asymmetry randomization and renal cysts. Here, we show that BICC1 is also expressed in both the pancreatic progenitor cells that line the ducts during development, and in the ducts after birth, but not in differentiated endocrine or acinar cells. Genetic inactivation of Bicc1 leads to ductal cell over-proliferation and cyst formation. Transcriptome comparison between WT and Bicc1 KO pancreata, before the phenotype onset, reveals that PKD2 functions downstream of BICC1 in preventing cyst formation in the pancreas. Moreover, the analysis highlights immune cell infiltration and stromal reaction developing early in the pancreas of Bicc1 knockout mice. In addition to these functions in duct morphogenesis, BICC1 regulates NEUROG3(+) endocrine progenitor production. Its deletion leads to a late but sustained endocrine progenitor decrease, resulting in a 50% reduction of endocrine cells. We show that BICC1 functions downstream of ONECUT1 in the pathway controlling both NEUROG3(+) endocrine cell production and ductal morphogenesis, and suggest a new candidate gene for syndromes associating kidney dysplasia with pancreatic disorders, including diabetes.
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Affiliation(s)
- Laurence A Lemaire
- DanStem, University of Copenhagen, 3B Blegdamsvej, Copenhagen N DK-2200, Denmark ISREC, Life Sciences, Ecole Polytechnique Fédérale de Lausanne, Lausanne CH-1015, Switzerland
| | - Joan Goulley
- ISREC, Life Sciences, Ecole Polytechnique Fédérale de Lausanne, Lausanne CH-1015, Switzerland
| | - Yung Hae Kim
- DanStem, University of Copenhagen, 3B Blegdamsvej, Copenhagen N DK-2200, Denmark ISREC, Life Sciences, Ecole Polytechnique Fédérale de Lausanne, Lausanne CH-1015, Switzerland
| | - Solenne Carat
- BBCF, Life Sciences, Ecole Polytechnique Fédérale de Lausanne, Lausanne CH-1015, Switzerland
| | - Patrick Jacquemin
- de Duve Institute, Université catholique de Louvain, Brussels B-1200, Belgium
| | - Jacques Rougemont
- BBCF, Life Sciences, Ecole Polytechnique Fédérale de Lausanne, Lausanne CH-1015, Switzerland
| | - Daniel B Constam
- ISREC, Life Sciences, Ecole Polytechnique Fédérale de Lausanne, Lausanne CH-1015, Switzerland
| | - Anne Grapin-Botton
- DanStem, University of Copenhagen, 3B Blegdamsvej, Copenhagen N DK-2200, Denmark ISREC, Life Sciences, Ecole Polytechnique Fédérale de Lausanne, Lausanne CH-1015, Switzerland
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46
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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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Piazzon N, Bernet F, Guihard L, Leonhard WN, Urfer S, Firsov D, Chehade H, Vogt B, Piergiovanni S, Peters DJM, Bonny O, Constam DB. Urine Fetuin-A is a biomarker of autosomal dominant polycystic kidney disease progression. J Transl Med 2015; 13:103. [PMID: 25888842 PMCID: PMC4416261 DOI: 10.1186/s12967-015-0463-7] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2014] [Accepted: 03/13/2015] [Indexed: 01/08/2023] Open
Abstract
Background Autosomal dominant polycystic kidney disease (ADPKD) is a genetic disorder characterized by numerous fluid-filled cysts that frequently result in end-stage renal disease. While promising treatment options are in advanced clinical development, early diagnosis and follow-up remain a major challenge. We therefore evaluated the diagnostic value of Fetuin-A as a new biomarker of ADPKD in human urine. Results We found that renal Fetuin-A levels are upregulated in both Pkd1 and Bicc1 mouse models of ADPKD. Measurement by ELISA revealed that urinary Fetuin-A levels were significantly higher in 66 ADPKD patients (17.5 ± 12.5 μg/mmol creatinine) compared to 17 healthy volunteers (8.5 ± 3.8 μg/mmol creatinine) or 50 control patients with renal diseases of other causes (6.2 ± 2.9 μg/mmol creatinine). Receiver operating characteristics (ROC) analysis of urinary Fetuin-A levels for ADPKD rendered an optimum cut-off value of 12.2 μg/mmol creatinine, corresponding to 94% of sensitivity and 60% of specificity (area under the curve 0.74 ; p = 0.0019). Furthermore, urinary Fetuin-A levels in ADPKD patients correlated with the degree of renal insufficiency and showed a significant increase in patients with preserved renal function followed for two years. Conclusions Our findings establish urinary Fetuin-A as a sensitive biomarker of the progression of ADPKD. Further studies are required to examine the pathogenic mechanisms of elevated renal and urinary Fetuin-A in ADPKD. Electronic supplementary material The online version of this article (doi:10.1186/s12967-015-0463-7) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Nathalie Piazzon
- Ecole Polytechnique Fédérale de Lausanne (EPFL), Bâtiment SV ISREC, Station 19, Lausanne, Switzerland. .,Department of Pharmacology and Toxicology, University of Lausanne (UNIL), Quartier UNIL-CHUV, Lausanne, Switzerland.
| | - Florian Bernet
- Ecole Polytechnique Fédérale de Lausanne (EPFL), Bâtiment SV ISREC, Station 19, Lausanne, Switzerland.
| | - Linda Guihard
- Service of Nephrology, Lausanne University Hospital (CHUV), Lausanne, Switzerland.
| | - Wouter N Leonhard
- Department of Human Genetics, Leiden Univ. Medical Center, Leiden, The Netherlands.
| | - Séverine Urfer
- Ecole Polytechnique Fédérale de Lausanne (EPFL), Bâtiment SV ISREC, Station 19, Lausanne, Switzerland.
| | - Dmitri Firsov
- Department of Pharmacology and Toxicology, University of Lausanne (UNIL), Quartier UNIL-CHUV, Lausanne, Switzerland.
| | - Hassib Chehade
- Department of Pediatrics, Division of Pediatric Nephrology, Lausanne University Hospital (CHUV), Lausanne, Switzerland.
| | - Bruno Vogt
- Department of Nephrology and Hypertension, Inselspital, Bern, Switzerland.
| | - Sophia Piergiovanni
- Department of Pharmacology and Toxicology, University of Lausanne (UNIL), Quartier UNIL-CHUV, Lausanne, Switzerland.
| | - Dorien J M Peters
- Department of Human Genetics, Leiden Univ. Medical Center, Leiden, The Netherlands.
| | - Olivier Bonny
- Department of Pharmacology and Toxicology, University of Lausanne (UNIL), Quartier UNIL-CHUV, Lausanne, Switzerland. .,Service of Nephrology, Lausanne University Hospital (CHUV), Lausanne, Switzerland.
| | - Daniel B Constam
- Ecole Polytechnique Fédérale de Lausanne (EPFL), Bâtiment SV ISREC, Station 19, Lausanne, Switzerland.
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Impaired epithelial Na+ channel activity contributes to cystogenesis and development of autosomal recessive polycystic kidney disease in PCK rats. Pediatr Res 2015; 77:64-9. [PMID: 25279988 PMCID: PMC4268054 DOI: 10.1038/pr.2014.145] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/27/2014] [Accepted: 07/16/2014] [Indexed: 02/08/2023]
Abstract
BACKGROUND Autosomal recessive polycystic kidney disease is a genetic disorder characterized by the development of renal cysts of tubular epithelial cell origin. Epithelial Na(+) channel (ENaC) is responsible for sodium reabsorption in the aldosterone-sensitive distal nephron. Here, we investigated the ENaC expression and activity in cystic tissue taken from rats with autosomal recessive polycystic kidney disease. METHODS Polycystic kidney (PCK) rats were treated with the selective ENaC inhibitor benzamil given in the drinking water, and after 4 or 12 wk, the severity of morphological malformations in the kidneys was assessed. ENaC and aquaporin-2 expression and ENaC activity were tested with immunohistochemistry and patch-clamp electrophysiology, respectively. RESULTS Treatment with benzamil exacerbated development of cysts compared with the vehicle-treated animals. In contrast, the 12 wk of treatment with the loop diuretic furosemide had no effect on cystogenesis. Single-channel patch-clamp analysis revealed that ENaC activity in the freshly isolated cystic epithelium was significantly lower than that in the noncystic collecting ducts isolated from PCK or normal Sprague-Dawley rats. Immunohistochemical analysis confirmed that β-ENaC and aquaporin-2 expressions in cysts are decreased compared with nondilated tubules from PCK rat kidneys. CONCLUSION We demonstrated that cystic epithelium exhibits low ENaC activity and this phenomenon can contribute to cyst progression.
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Abstract
The synthesis of nonpeptide orally bioavailable vasopressin antagonists devoid of agonistic activity (vaptans) has made possible the selective blockade of vasopressin receptor subtypes for therapeutic purposes. Vaptans acting on the vasopressin V2 receptors (aquaretics) have attracted attention as a possible therapy for heart failure and polycystic kidney disease. Despite a solid rationale and encouraging preclinical testing, aquaretics have not improved clinical outcomes in randomized clinical trials for heart failure. Additional clinical trials with select population targets, more flexible dosing schedules, and possibly a different drug type or combination (balanced V1a/V2 receptor antagonism) may be warranted. Aquaretics are promising for the treatment of autosomal dominant polycystic kidney disease and have been approved in Japan for this indication. More studies are needed to better define their long-term safety and efficacy and optimize their utilization.
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Affiliation(s)
- Vicente E Torres
- Division of Nephrology and Hypertension, Mayo Clinic College of Medicine, Rochester, Minnesota 55905;
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50
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Sussman CR, Ward CJ, Leightner AC, Smith JL, Agarwal R, Harris PC, Torres VE. Phosphodiesterase 1A modulates cystogenesis in zebrafish. J Am Soc Nephrol 2014; 25:2222-30. [PMID: 24700876 PMCID: PMC4178429 DOI: 10.1681/asn.2013040421] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2013] [Accepted: 01/21/2014] [Indexed: 12/17/2022] Open
Abstract
Substantial evidence indicates the importance of elevated cAMP in polycystic kidney disease (PKD). Accumulation of cAMP in cystic tissues may be, in part, caused by enhanced adenylyl cyclase activity, but inhibition of cAMP degradation by phosphodiesterases (PDE) likely has an important role, because cAMP is inactivated much faster than it is synthesized. PDE1 is the only PDE family activated by Ca(2+), which is reduced in PKD cells. To assess the contribution of the PDE1A subfamily to renal cyst formation, we examined the expression and function of PDE1A in zebrafish. We identified two splice isoforms with alternative starts corresponding to human PDE1A1 and PDE1A4. Expression of the two isoforms varied in embryos and adult tissues, and both isoforms hydrolyzed cAMP with Ca(2+)/calmodulin dependence. Depletion of PDE1A in zebrafish embryos using splice- and translation-blocking morpholinos (MOs) caused pronephric cysts, hydrocephalus, and body curvature. Human PDE1A RNA and the PKA inhibitors, H89 and Rp-cAMPS, partially rescued phenotypes of pde1a morphants. Additionally, MO depletion of PDE1A aggravated phenotypes in pkd2 morphants, causing more severe body curvature, and human PDE1A RNA partially rescued pkd2 morphant phenotypes, pronephric cysts, hydrocephalus, and body curvature. Together, these data indicate the integral role of PDE1A and cAMP signaling in renal development and cystogenesis, imply that PDE1A activity is altered downstream of polycystin-2, and suggest that PDE1A is a viable drug target for PKD.
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Affiliation(s)
- Caroline R Sussman
- Nephrology and Hypertension, Mayo Clinic College of Medicine, Rochester, Minnesota
| | - Christopher J Ward
- Nephrology and Hypertension, Mayo Clinic College of Medicine, Rochester, Minnesota
| | - Amanda C Leightner
- Nephrology and Hypertension, Mayo Clinic College of Medicine, Rochester, Minnesota
| | - Jordan L Smith
- Nephrology and Hypertension, Mayo Clinic College of Medicine, Rochester, Minnesota
| | - Reema Agarwal
- Nephrology and Hypertension, Mayo Clinic College of Medicine, Rochester, Minnesota
| | - Peter C Harris
- Nephrology and Hypertension, Mayo Clinic College of Medicine, Rochester, Minnesota
| | - Vicente E Torres
- Nephrology and Hypertension, Mayo Clinic College of Medicine, Rochester, Minnesota
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