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Prajapati M, Zhang JZ, Chong GS, Chiu L, Mercadante CJ, Kowalski HL, Antipova O, Lai B, Ralle M, Jackson BP, Punshon T, Guo S, Aghajan M, Bartnikas TB. Manganese transporter SLC30A10 and iron transporters SLC40A1 and SLC11A2 impact dietary manganese absorption. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.07.17.603814. [PMID: 39071439 PMCID: PMC11275741 DOI: 10.1101/2024.07.17.603814] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/30/2024]
Abstract
SLC30A10 deficiency is a disease of severe manganese excess attributed to loss of SLC30A10-dependent manganese excretion via the gastrointestinal tract. Patients develop dystonia, cirrhosis, and polycythemia. They are treated with chelators but also respond to oral iron, suggesting that iron can outcompete manganese for absorption in this disease. Here we explore the latter observation. Intriguingly, manganese absorption is increased in Slc30a10-deficient mice despite manganese excess. Studies of multiple mouse models indicate that increased dietary manganese absorption reflects two processes: loss of manganese export from enterocytes into the gastrointestinal tract lumen by SLC30A10, and increased absorption of dietary manganese by iron transporters SLC11A2 (DMT1) and SLC40A1 (ferroportin). Our work demonstrates that aberrant absorption contributes prominently to SLC30A10 deficiency and expands our understanding of biological interactions between iron and manganese. Based on these results, we propose a reconsideration of the role of iron transporters in manganese homeostasis is warranted.
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Affiliation(s)
- Milankumar Prajapati
- Department of Pathology and Laboratory Medicine, Brown University, Providence, RI, 02912, USA
| | - Jared Z. Zhang
- Department of Pathology and Laboratory Medicine, Brown University, Providence, RI, 02912, USA
| | - Grace S. Chong
- Department of Pathology and Laboratory Medicine, Brown University, Providence, RI, 02912, USA
| | - Lauren Chiu
- Department of Pathology and Laboratory Medicine, Brown University, Providence, RI, 02912, USA
| | - Courtney J. Mercadante
- Department of Pathology and Laboratory Medicine, Brown University, Providence, RI, 02912, USA
| | - Heather L. Kowalski
- Department of Pathology and Laboratory Medicine, Brown University, Providence, RI, 02912, USA
| | - Olga Antipova
- Advanced Photon Source, Argonne National Laboratory, Argonne, IL, 60439, USA
| | - Barry Lai
- Advanced Photon Source, Argonne National Laboratory, Argonne, IL, 60439, USA
| | - Martina Ralle
- Department of Molecular and Medical Genetics, Oregon Health & Science University, Portland, OR, 97239, USA
| | - Brian P. Jackson
- Biomedical National Elemental Imaging Resource, Dartmouth College, Hanover, NH, 03755, USA
| | - Tracy Punshon
- Biomedical National Elemental Imaging Resource, Dartmouth College, Hanover, NH, 03755, USA
| | - Shuling Guo
- Ionis Pharmaceuticals, Inc., Carlsbad, CA, 92010, USA
| | | | - Thomas B. Bartnikas
- Department of Pathology and Laboratory Medicine, Brown University, Providence, RI, 02912, USA
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Prajapati M, Zhang JZ, Chiu L, Chong GS, Mercadante CJ, Kowalski HL, Delaney B, Anderson JA, Guo S, Aghajan M, Bartnikas TB. Hepatic HIF2 is a key determinant of manganese excess and polycythemia in SLC30A10 deficiency. JCI Insight 2024; 9:e169738. [PMID: 38652538 PMCID: PMC11141921 DOI: 10.1172/jci.insight.169738] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2023] [Accepted: 04/10/2024] [Indexed: 04/25/2024] Open
Abstract
Manganese is an essential yet potentially toxic metal. Initially reported in 2012, mutations in SLC30A10 are the first known inherited cause of manganese excess. SLC30A10 is an apical membrane protein that exports manganese from hepatocytes into bile and from enterocytes into the lumen of the gastrointestinal tract. SLC30A10 deficiency results in impaired gastrointestinal manganese excretion, leading to manganese excess, neurologic deficits, liver cirrhosis, polycythemia, and erythropoietin excess. Neurologic and liver disease are attributed to manganese toxicity. Polycythemia is attributed to erythropoietin excess. The goal of this study was to determine the basis of erythropoietin excess in SLC30A10 deficiency. Here, we demonstrate that transcription factors hypoxia-inducible factor 1a (Hif1a) and 2a (Hif2a), key mediators of the cellular response to hypoxia, are both upregulated in livers of Slc30a10-deficient mice. Hepatic Hif2a deficiency corrected erythropoietin expression and polycythemia and attenuated aberrant hepatic gene expression in Slc30a10-deficient mice, while hepatic Hif1a deficiency had no discernible impact. Hepatic Hif2a deficiency also attenuated manganese excess, though the underlying cause of this is not clear at this time. Overall, our results indicate that hepatic HIF2 is a key determinant of pathophysiology in SLC30A10 deficiency and expand our understanding of the contribution of HIFs to human disease.
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Affiliation(s)
- Milankumar Prajapati
- Department of Pathology and Laboratory Medicine, Brown University, Providence, Rhode Island, USA
| | - Jared Z. Zhang
- Department of Pathology and Laboratory Medicine, Brown University, Providence, Rhode Island, USA
| | - Lauren Chiu
- Department of Pathology and Laboratory Medicine, Brown University, Providence, Rhode Island, USA
| | - Grace S. Chong
- Department of Pathology and Laboratory Medicine, Brown University, Providence, Rhode Island, USA
| | - Courtney J. Mercadante
- Department of Pathology and Laboratory Medicine, Brown University, Providence, Rhode Island, USA
| | - Heather L. Kowalski
- Department of Pathology and Laboratory Medicine, Brown University, Providence, Rhode Island, USA
| | - Bradley Delaney
- Department of Pathology and Laboratory Medicine, Brown University, Providence, Rhode Island, USA
| | - Jessica A. Anderson
- Department of Pathology and Laboratory Medicine, Brown University, Providence, Rhode Island, USA
| | - Shuling Guo
- Ionis Pharmaceuticals, Inc., Carlsbad, California, USA
| | | | - Thomas B. Bartnikas
- Department of Pathology and Laboratory Medicine, Brown University, Providence, Rhode Island, USA
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3
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Azucenas CR, Ruwe TA, Bonamer JP, Qiao B, Ganz T, Jormakka M, Nemeth E, Mackenzie B. Comparative analysis of the functional properties of human and mouse ferroportin. Am J Physiol Cell Physiol 2023; 324:C1110-C1118. [PMID: 36939203 PMCID: PMC10191125 DOI: 10.1152/ajpcell.00063.2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2023] [Revised: 03/16/2023] [Accepted: 03/16/2023] [Indexed: 03/21/2023]
Abstract
Ferroportin (Fpn)-expressed at the plasma membrane of macrophages, enterocytes, and hepatocytes-mediates the transfer of cellular iron into the blood plasma. Under the control of the iron-regulatory hormone hepcidin, Fpn serves a critical role in systemic iron homeostasis. Although we have previously characterized human Fpn, a great deal of research in iron homeostasis and disorders uses mouse models. By way of example, the flatiron mouse, a model of classical ferroportin disease, bears the mutation H32R in Fpn and is characterized by systemic iron deficiency and macrophage iron retention. The flatiron mouse also appears to exhibit a manganese phenotype, raising the possibility that mouse Fpn serves a role in manganese metabolism. At odds with this observation, we have found that human Fpn does not transport manganese, so we considered the possibility that a species difference could explain this discrepancy. We tested the hypothesis that mouse but not human Fpn can transport manganese and performed a comparative analysis of mouse and human Fpn. We examined the functional properties of human Fpn, mouse Fpn, and mutant mouse Fpn by using radiotracer assays in RNA-injected Xenopus oocytes. We found that neither mouse nor human Fpn transports manganese. Mouse and human Fpn share identical properties with respect to substrate profile, calcium dependence, optimal pH, and hepcidin sensitivity. We have also demonstrated that Fpn is not an ATPase pump. Our findings validate the use of mouse models of ferroportin function in iron homeostasis and disease.
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Affiliation(s)
- Corbin R Azucenas
- Department of Pharmacology & Systems Physiology, University of Cincinnati College of Medicine, Cincinnati, Ohio, United States
- Medical Sciences Program, University of Cincinnati College of Medicine, Cincinnati, Ohio, United States
- Systems Biology & Physiology Program, University of Cincinnati College of Medicine, Cincinnati, Ohio, United States
| | - T Alex Ruwe
- Department of Pharmacology & Systems Physiology, University of Cincinnati College of Medicine, Cincinnati, Ohio, United States
- Systems Biology & Physiology Program, University of Cincinnati College of Medicine, Cincinnati, Ohio, United States
| | - John P Bonamer
- Department of Pharmacology & Systems Physiology, University of Cincinnati College of Medicine, Cincinnati, Ohio, United States
| | - Bo Qiao
- Department of Medicine, David Geffen School of Medicine at UCLA, Los Angeles, California, United States
| | - Tomas Ganz
- Department of Medicine, David Geffen School of Medicine at UCLA, Los Angeles, California, United States
- Department of Pathology, David Geffen School of Medicine at UCLA, Los Angeles, California, United States
| | - Mika Jormakka
- Department of Cell Biology, Graduate School of Medicine, Kyoto University, Kyoto, Japan
| | - Elizabeta Nemeth
- Department of Medicine, David Geffen School of Medicine at UCLA, Los Angeles, California, United States
| | - Bryan Mackenzie
- Department of Pharmacology & Systems Physiology, University of Cincinnati College of Medicine, Cincinnati, Ohio, United States
- Medical Sciences Program, University of Cincinnati College of Medicine, Cincinnati, Ohio, United States
- Systems Biology & Physiology Program, University of Cincinnati College of Medicine, Cincinnati, Ohio, United States
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4
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Prajapati M, Zhang JZ, Mercadante CJ, Kowalski HL, Delaney B, Anderson JA, Guo S, Aghajan M, Bartnikas TB. Hypoxia-inducible factor 2 is a key determinant of manganese excess and polycythemia in SLC30A10 deficiency. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.02.20.529270. [PMID: 36865210 PMCID: PMC9980069 DOI: 10.1101/2023.02.20.529270] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/23/2023]
Abstract
Manganese is an essential yet potentially toxic metal. Initially reported in 2012, mutations in SLC30A10 are the first known inherited cause of manganese excess. SLC30A10 is an apical membrane transport protein that exports manganese from hepatocytes into bile and from enterocytes into the lumen of the gastrointestinal tract. SLC30A10 deficiency results in impaired gastrointestinal manganese excretion, leading to severe manganese excess, neurologic deficits, liver cirrhosis, polycythemia, and erythropoietin excess. Neurologic and liver disease are attributed to manganese toxicity. Polycythemia is attributed to erythropoietin excess, but the basis of erythropoietin excess in SLC30A10 deficiency has yet to be established. Here we demonstrate that erythropoietin expression is increased in liver but decreased in kidneys in Slc30a10-deficient mice. Using pharmacologic and genetic approaches, we show that liver expression of hypoxia-inducible factor 2 (Hif2), a transcription factor that mediates the cellular response to hypoxia, is essential for erythropoietin excess and polycythemia in Slc30a10-deficient mice, while hypoxia-inducible factor 1 (HIF1) plays no discernible role. RNA-seq analysis determined that Slc30a10-deficient livers exhibit aberrant expression of a large number of genes, most of which align with cell cycle and metabolic processes, while hepatic Hif2 deficiency attenuates differential expression of half of these genes in mutant mice. One such gene downregulated in Slc30a10-deficient mice in a Hif2-dependent manner is hepcidin, a hormonal inhibitor of dietary iron absorption. Our analyses indicate that hepcidin downregulation serves to increase iron absorption to meet the demands of erythropoiesis driven by erythropoietin excess. Finally, we also observed that hepatic Hif2 deficiency attenuates tissue manganese excess, although the underlying cause of this observation is not clear at this time. Overall, our results indicate that HIF2 is a key determinant of pathophysiology in SLC30A10 deficiency.
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Affiliation(s)
- Milankumar Prajapati
- Department of Pathology and Laboratory Medicine, Brown University, Providence, Rhode Island, 02912, USA
| | - Jared Z. Zhang
- Department of Pathology and Laboratory Medicine, Brown University, Providence, Rhode Island, 02912, USA
| | - Courtney J. Mercadante
- Department of Pathology and Laboratory Medicine, Brown University, Providence, Rhode Island, 02912, USA
| | - Heather L. Kowalski
- Department of Pathology and Laboratory Medicine, Brown University, Providence, Rhode Island, 02912, USA
| | - Bradley Delaney
- Department of Pathology and Laboratory Medicine, Brown University, Providence, Rhode Island, 02912, USA
| | - Jessica A. Anderson
- Department of Pathology and Laboratory Medicine, Brown University, Providence, Rhode Island, 02912, USA
| | - Shuling Guo
- Ionis Pharmaceuticals, Inc., Carlsbad, CA, 92010, USA
| | | | - Thomas B. Bartnikas
- Department of Pathology and Laboratory Medicine, Brown University, Providence, Rhode Island, 02912, USA
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Bağda E, Altundağ H, Keskin CS. Deep Eutectic Solvent-based Extraction of As, Mn, Pb, Cr, and Ni from Spleen, Kidney, and Brain Samples. JOURNAL OF ANALYTICAL CHEMISTRY 2022. [DOI: 10.1134/s1061934822090027] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Vadolas J, Ng GZ, Kysenius K, Crouch PJ, Dames S, Eisermann M, Nualkaew T, Vilcassim S, Schaeper U, Grigoriadis G. SLN124, a GalNac-siRNA targeting transmembrane serine protease 6, in combination with deferiprone therapy reduces ineffective erythropoiesis and hepatic iron-overload in a mouse model of β-thalassaemia. Br J Haematol 2021; 194:200-210. [PMID: 33942901 PMCID: PMC8359948 DOI: 10.1111/bjh.17428] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2021] [Accepted: 03/02/2021] [Indexed: 02/06/2023]
Abstract
Beta‐thalassaemia is an inherited blood disorder characterised by ineffective erythropoiesis and anaemia. Consequently, hepcidin expression is reduced resulting in increased iron absorption and primary iron overload. Hepcidin is under the negative control of transmembrane serine protease 6 (TMPRSS6) via cleavage of haemojuvelin (HJV), a co‐receptor for the bone morphogenetic protein (BMP)‐mothers against decapentaplegic homologue (SMAD) signalling pathway. Considering the central role of the TMPRSS6/HJV/hepcidin axis in iron homeostasis, the inhibition of TMPRSS6 expression represents a promising therapeutic strategy to increase hepcidin production and ameliorate anaemia and iron overload in β‐thalassaemia. In the present study, we investigated a small interfering RNA (siRNA) conjugate optimised for hepatic targeting of Tmprss6 (SLN124) in β‐thalassaemia mice (Hbbth3/+). Two subcutaneous injections of SLN124 (3 mg/kg) were sufficient to normalise hepcidin expression and reduce anaemia. We also observed a significant improvement in erythroid maturation, which was associated with a significant reduction in splenomegaly. Treatment with the iron chelator, deferiprone (DFP), did not impact any of the erythroid parameters. However, the combination of SLN124 with DFP was more effective in reducing hepatic iron overload than either treatment alone. Collectively, we show that the combination therapy can ameliorate several disease symptoms associated with chronic anaemia and iron overload, and therefore represents a promising pharmacological modality for the treatment of β‐thalassaemia and related disorders.
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Affiliation(s)
- Jim Vadolas
- Department of Molecular and Translational Sciences, Monash University, Clayton, VIC, Australia.,Centre for Cancer Research, Hudson Institute of Medical Research, Clayton, VIC, Australia
| | - Garrett Z Ng
- Department of Biochemistry and Molecular Biology, Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Parkville, Australia
| | - Kai Kysenius
- Department of Pharmacology and Therapeutics, Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Melbourne, VIC, Australia
| | - Peter J Crouch
- Department of Pharmacology and Therapeutics, Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Melbourne, VIC, Australia
| | | | | | - Tiwaporn Nualkaew
- Centre for Cancer Research, Hudson Institute of Medical Research, Clayton, VIC, Australia
| | - Shahla Vilcassim
- School of Clinical Sciences at Monash Health, Monash University, Clayton, VIC, Australia
| | | | - George Grigoriadis
- Centre for Cancer Research, Hudson Institute of Medical Research, Clayton, VIC, Australia.,School of Clinical Sciences at Monash Health, Monash University, Clayton, VIC, Australia
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Iron and manganese transport in mammalian systems. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2020; 1868:118890. [PMID: 33091506 DOI: 10.1016/j.bbamcr.2020.118890] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 07/21/2020] [Revised: 09/24/2020] [Accepted: 10/08/2020] [Indexed: 12/23/2022]
Abstract
Studies in recent years have significantly expanded, refined, and redefined the repertoire of transporters and other proteins involved in iron and manganese (Mn) transport and homeostasis. In this review, we discuss highlights of the recent literature on iron and Mn transport, focusing on the roles of membrane transporters and related proteins. Studies are considered from the vantage point of main organs, tissues, and cell types that actively control whole-body iron or Mn homeostasis, with emphasis on studies in which in vivo metal transport was measured directly or implicated by using knockout mouse models. Overviews of whole-body and cellular iron and Mn homeostasis are also provided to give physiological context for key transporters and to highlight how they participate in the uptake, intracellular trafficking, and efflux of each metal. Important similarities and differences in iron and Mn transport are noted, and future research opportunities and challenges are identified.
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Horning KJ, Joshi P, Nitin R, Balachandran RC, Yanko FM, Kim K, Christov P, Aschner M, Sulikowski GA, Weaver CD, Bowman AB. Identification of a selective manganese ionophore that enables nonlethal quantification of cellular manganese. J Biol Chem 2020; 295:3875-3890. [PMID: 32047113 PMCID: PMC7086026 DOI: 10.1074/jbc.ra119.009781] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2019] [Revised: 02/11/2020] [Indexed: 01/14/2023] Open
Abstract
Available assays for measuring cellular manganese (Mn) levels require cell lysis, restricting longitudinal experiments and multiplexed outcome measures. Conducting a screen of small molecules known to alter cellular Mn levels, we report here that one of these chemicals induces rapid Mn efflux. We describe this activity and the development and implementation of an assay centered on this small molecule, named manganese-extracting small molecule (MESM). Using inductively-coupled plasma-MS, we validated that this assay, termed here "manganese-extracting small molecule estimation route" (MESMER), can accurately assess Mn in mammalian cells. Furthermore, we found evidence that MESM acts as a Mn-selective ionophore, and we observed that it has increased rates of Mn membrane transport, reduced cytotoxicity, and increased selectivity for Mn over calcium compared with two established Mn ionophores, calcimycin (A23187) and ionomycin. Finally, we applied MESMER to test whether prior Mn exposures subsequently affect cellular Mn levels. We found that cells receiving continuous, elevated extracellular Mn accumulate less Mn than cells receiving equally-elevated Mn for the first time for 24 h, indicating a compensatory cellular homeostatic response. Use of the MESMER assay versus a comparable detergent lysis-based assay, cellular Fura-2 Mn extraction assay, reduced the number of cells and materials required for performing a similar but cell lethality-based experiment to 25% of the normally required sample size. We conclude that MESMER can accurately quantify cellular Mn levels in two independent cells lines through an ionophore-based mechanism, maintaining cell viability and enabling longitudinal assessment within the same cultures.
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Affiliation(s)
- Kyle J. Horning
- Vanderbilt Brain Institute, Vanderbilt University, Nashville, Tennessee 37232
| | - Piyush Joshi
- Vanderbilt Brain Institute, Vanderbilt University, Nashville, Tennessee 37232
| | - Rachana Nitin
- Vanderbilt Brain Institute, Vanderbilt University, Nashville, Tennessee 37232
| | | | - Frank M. Yanko
- School of Health Sciences, Purdue University, West Lafayette, Indiana 47907
| | - Kwangho Kim
- Vanderbilt Institute of Chemical Biology, Vanderbilt University, Nashville, Tennessee 37232,Department of Chemistry, Vanderbilt University, Nashville, Tennessee 37235
| | - Plamen Christov
- Vanderbilt Institute of Chemical Biology, Vanderbilt University, Nashville, Tennessee 37232
| | - Michael Aschner
- Department of Molecular Pharmacology, Albert Einstein College of Medicine, Bronx, New York 10461
| | - Gary A. Sulikowski
- Vanderbilt Institute of Chemical Biology, Vanderbilt University, Nashville, Tennessee 37232,Department of Chemistry, Vanderbilt University, Nashville, Tennessee 37235,Department of Pharmacology, Vanderbilt University, Nashville, Tennessee 37212
| | - C. David Weaver
- Department of Chemistry, Vanderbilt University, Nashville, Tennessee 37235,Department of Pharmacology, Vanderbilt University, Nashville, Tennessee 37212
| | - Aaron B. Bowman
- Vanderbilt Brain Institute, Vanderbilt University, Nashville, Tennessee 37232,School of Health Sciences, Purdue University, West Lafayette, Indiana 47907, To whom correspondence should be addressed:
Purdue University, 550 Stadium Mall Dr., HAMP 1173A, West Lafayette, IN 47907-2051. E-mail:
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9
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Mercadante CJ, Prajapati M, Conboy HL, Dash ME, Herrera C, Pettiglio MA, Cintron-Rivera L, Salesky MA, Rao DB, Bartnikas TB. Manganese transporter Slc30a10 controls physiological manganese excretion and toxicity. J Clin Invest 2019; 129:5442-5461. [PMID: 31527311 PMCID: PMC6877324 DOI: 10.1172/jci129710] [Citation(s) in RCA: 59] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2019] [Accepted: 09/10/2019] [Indexed: 12/30/2022] Open
Abstract
Manganese (Mn), an essential metal and nutrient, is toxic in excess. Toxicity classically results from inhalational exposures in individuals who work in industrial settings. The first known disease of inherited Mn excess, identified in 2012, is caused by mutations in the metal exporter SLC30A10 and is characterized by Mn excess, dystonia, cirrhosis, and polycythemia. To investigate the role of SLC30A10 in Mn homeostasis, we first generated whole-body Slc30a10-deficient mice, which developed severe Mn excess and impaired systemic and biliary Mn excretion. Slc30a10 localized to canalicular membranes of hepatocytes, but mice with liver Slc30a10 deficiency developed minimal Mn excess despite impaired biliary Mn excretion. Slc30a10 also localized to the apical membrane of enterocytes, but mice with Slc30a10 deficiency in small intestines developed minimal Mn excess despite impaired Mn export into the lumen of the small intestines. Finally, mice with Slc30a10 deficiency in liver and small intestines developed Mn excess that was less severe than that observed in mice with whole-body Slc30a10 deficiency, suggesting that additional sites of Slc30a10 expression contribute to Mn homeostasis. Overall, these results indicated that Slc30a10 is essential for Mn excretion by hepatocytes and enterocytes and could be an effective target for pharmacological intervention to treat Mn toxicity.
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Affiliation(s)
- Courtney J. Mercadante
- Department of Pathology and Laboratory Medicine, Brown University, Providence, Rhode Island, USA
| | - Milankumar Prajapati
- Department of Pathology and Laboratory Medicine, Brown University, Providence, Rhode Island, USA
| | - Heather L. Conboy
- Department of Pathology and Laboratory Medicine, Brown University, Providence, Rhode Island, USA
| | - Miriam E. Dash
- Department of Pathology and Laboratory Medicine, Brown University, Providence, Rhode Island, USA
| | - Carolina Herrera
- Department of Pathology and Laboratory Medicine, Brown University, Providence, Rhode Island, USA
| | - Michael A. Pettiglio
- Department of Pathology and Laboratory Medicine, Brown University, Providence, Rhode Island, USA
| | - Layra Cintron-Rivera
- Department of Pathology and Laboratory Medicine, Brown University, Providence, Rhode Island, USA
| | - Madeleine A. Salesky
- Department of Pathology and Laboratory Medicine, Brown University, Providence, Rhode Island, USA
| | - Deepa B. Rao
- Center for Drug Evaluation and Research, US Food and Drug Administration, Silver Spring, Maryland, USA
| | - Thomas B. Bartnikas
- Department of Pathology and Laboratory Medicine, Brown University, Providence, Rhode Island, USA
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