1
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Sillence DO. A Dyadic Nosology for Osteogenesis Imperfecta and Bone Fragility Syndromes 2024. Calcif Tissue Int 2024:10.1007/s00223-024-01248-7. [PMID: 38942908 DOI: 10.1007/s00223-024-01248-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/24/2024] [Accepted: 06/17/2024] [Indexed: 06/30/2024]
Abstract
In 2023 following extensive consultation with key stakeholders, the expert Nosology Working Group of the International Skeletal Dysplasia Society (ISDS) published the new Dyadic Nosology for Genetic Disorders of the Skeleton. Some 770 entities were delineated associated with 552 genes. From these entities, over 40 genes resulting in distinct forms of Osteogenesis Imperfecta (OI) and Bone Fragility and/or Familial Osteoporosis were identified. To assist clinicians and lay stake holders and bring the considerable body of knowledge of the matrix biology and genomics to people with OI as well as to clinicians and scientists, a dyadic nosology has been recommended. This combines a genomic co-descriptor with a phenotypic naming based on the widely used Sillence nosology for the OI syndromes and the many other syndromes characterized in part by bone fragility.This review recapitulates and explains the evolution from the simple Congenita and Tarda subclassification of OI in the 1970 nosology, which was replaced by the Sillence types I-IV nosology which was again replaced in 2009 with 5 clinical groups, type 1 to 5. Qualitative and quantitative defects in type I collagen polypeptides were postulated to account for the genetic heterogeneity in OI for nearly 30 years, when OI type 5, a non-collagen disorder was recognized. Advances in matrix biology and genomics since that time have confirmed a surprising complexity both in transcriptional as well as post-translational mechanisms of collagens as well as in the many mechanisms of calcified tissue homeostasis and integrity.
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Affiliation(s)
- David Owen Sillence
- Specialities of Genomic Medicine and Paediatrics and Adolescent Health, Children's Hospital Westmead, Sydney University Clinical School, Westmead, NSW, 2145, Australia.
- Department of Genetic Medicine, Honorary Emeritus Consultant, Westmead Hospital, Westmead, NSW, 2145, Australia.
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2
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Rohacs T. Phosphoinositide Regulation of TRP Channels: A Functional Overview in the Structural Era. Annu Rev Physiol 2024; 86:329-355. [PMID: 37871124 DOI: 10.1146/annurev-physiol-042022-013956] [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] [Indexed: 10/25/2023]
Abstract
Transient receptor potential (TRP) ion channels have diverse activation mechanisms including physical stimuli, such as high or low temperatures, and a variety of intracellular signaling molecules. Regulation by phosphoinositides and their derivatives is their only known common regulatory feature. For most TRP channels, phosphatidylinositol 4,5-bisphosphate [PI(4,5)P2] serves as a cofactor required for activity. Such dependence on PI(4,5)P2 has been demonstrated for members of the TRPM subfamily and for the epithelial TRPV5 and TRPV6 channels. Intracellular TRPML channels show specific activation by PI(3,5)P2. Structural studies uncovered the PI(4,5)P2 and PI(3,5)P2 binding sites for these channels and shed light on the mechanism of channel opening. PI(4,5)P2 regulation of TRPV1-4 as well as some TRPC channels is more complex, involving both positive and negative effects. This review discusses the functional roles of phosphoinositides in TRP channel regulation and molecular insights gained from recent cryo-electron microscopy structures.
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Affiliation(s)
- Tibor Rohacs
- Department of Pharmacology, Physiology and Neuroscience, Rutgers New Jersey Medical School, Newark, New Jersey;
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3
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Huang J, Korsunsky A, Yazdani M, Chen J. Targeting TRP channels: recent advances in structure, ligand binding, and molecular mechanisms. Front Mol Neurosci 2024; 16:1334370. [PMID: 38273937 PMCID: PMC10808746 DOI: 10.3389/fnmol.2023.1334370] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2023] [Accepted: 12/26/2023] [Indexed: 01/27/2024] Open
Abstract
Transient receptor potential (TRP) channels are a large and diverse family of transmembrane ion channels that are widely expressed, have important physiological roles, and are associated with many human diseases. These proteins are actively pursued as promising drug targets, benefitting greatly from advances in structural and mechanistic studies of TRP channels. At the same time, the complex, polymodal activation and regulation of TRP channels have presented formidable challenges. In this short review, we summarize recent progresses toward understanding the structural basis of TRP channel function, as well as potential ligand binding sites that could be targeted for therapeutics. A particular focus is on the current understanding of the molecular mechanisms of TRP channel activation and regulation, where many fundamental questions remain unanswered. We believe that a deeper understanding of the functional mechanisms of TRP channels will be critical and likely transformative toward developing successful therapeutic strategies targeting these exciting proteins. This endeavor will require concerted efforts from computation, structural biology, medicinal chemistry, electrophysiology, pharmacology, drug safety and clinical studies.
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Affiliation(s)
- Jian Huang
- Department of Chemistry, University of Massachusetts, Amherst, MA, United States
| | - Aron Korsunsky
- Department of Chemistry, University of Massachusetts, Amherst, MA, United States
| | - Mahdieh Yazdani
- Modeling and Informatics, Merck & Co., Inc., West Point, PA, United States
| | - Jianhan Chen
- Department of Chemistry, University of Massachusetts, Amherst, MA, United States
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4
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Humer C, Radiskovic T, Horváti K, Lindinger S, Groschner K, Romanin C, Höglinger C. Bidirectional Allosteric Coupling between PIP 2 Binding and the Pore of the Oncochannel TRPV6. Int J Mol Sci 2024; 25:618. [PMID: 38203789 PMCID: PMC10779433 DOI: 10.3390/ijms25010618] [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: 12/08/2023] [Revised: 12/31/2023] [Accepted: 01/01/2024] [Indexed: 01/12/2024] Open
Abstract
The epithelial ion channel TRPV6 plays a pivotal role in calcium homeostasis. Channel function is intricately regulated at different stages, involving the lipid phosphatidylinositol-4,5-bisphosphate (PIP2). Given that dysregulation of TRPV6 is associated with various diseases, including different types of cancer, there is a compelling need for its pharmacological targeting. Structural studies provide insights on how TRPV6 is affected by different inhibitors, with some binding to sites else occupied by lipids. These include the small molecule cis-22a, which, however, also binds to and thereby blocks the pore. By combining calcium imaging, electrophysiology and optogenetics, we identified residues within the pore and the lipid binding site that are relevant for regulation by cis-22a and PIP2 in a bidirectional manner. Yet, mutation of the cytosolic pore exit reduced inhibition by cis-22a but preserved sensitivity to PIP2 depletion. Our data underscore allosteric communication between the lipid binding site and the pore and vice versa for most sites along the pore.
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Affiliation(s)
- Christina Humer
- Institute of Biophysics, Johannes Kepler University Linz, 4020 Linz, Austria; (C.H.); (T.R.); (C.R.)
| | - Tamara Radiskovic
- Institute of Biophysics, Johannes Kepler University Linz, 4020 Linz, Austria; (C.H.); (T.R.); (C.R.)
| | - Kata Horváti
- Institute of Materials and Environmental Chemistry, Research Centre for Natural Sciences, 1117 Budapest, Hungary;
| | - Sonja Lindinger
- Institute of Biophysics, Johannes Kepler University Linz, 4020 Linz, Austria; (C.H.); (T.R.); (C.R.)
| | - Klaus Groschner
- Gottfried Schatz Research Center, Division of Biophysics, Medical University of Graz, 8010 Graz, Austria;
| | - Christoph Romanin
- Institute of Biophysics, Johannes Kepler University Linz, 4020 Linz, Austria; (C.H.); (T.R.); (C.R.)
| | - Carmen Höglinger
- Institute of Biophysics, Johannes Kepler University Linz, 4020 Linz, Austria; (C.H.); (T.R.); (C.R.)
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5
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Kim M, Hong KT, Park HJ, Kim BK, Lee YJ, Choi JY, Choi YH, Park SH, Kim HS, Kang HJ. Use of larotrectinib in a pediatric patient with NTRK-rearranged spindle cell neoplasm and subsequent recurring bone fracture. Pediatr Blood Cancer 2023; 70:e30679. [PMID: 37715725 DOI: 10.1002/pbc.30679] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/30/2023] [Accepted: 09/04/2023] [Indexed: 09/18/2023]
Affiliation(s)
- Minji Kim
- Department of Pediatrics, Seoul National University College of Medicine, Seoul National University Children's Hospital, Seoul, Republic of Korea
| | - Kyung Taek Hong
- Department of Pediatrics, Seoul National University College of Medicine, Seoul National University Children's Hospital, Seoul, Republic of Korea
- Seoul National University Cancer Research Institute, Seoul, Republic of Korea
| | - Hyun Jin Park
- Department of Pediatrics, Seoul National University College of Medicine, Seoul National University Children's Hospital, Seoul, Republic of Korea
- Seoul National University Cancer Research Institute, Seoul, Republic of Korea
| | - Bo Kyung Kim
- Department of Pediatrics, Seoul National University College of Medicine, Seoul National University Children's Hospital, Seoul, Republic of Korea
- Seoul National University Cancer Research Institute, Seoul, Republic of Korea
| | - Yun Jeong Lee
- Department of Pediatrics, Seoul National University College of Medicine, Seoul National University Children's Hospital, Seoul, Republic of Korea
| | - Jung Yoon Choi
- Department of Pediatrics, Seoul National University College of Medicine, Seoul National University Children's Hospital, Seoul, Republic of Korea
- Seoul National University Cancer Research Institute, Seoul, Republic of Korea
| | - Young Hun Choi
- Department of Radiology, Seoul National University College of Medicine, Seoul National University Hospital, Seoul, Republic of Korea
| | - Sung-Hye Park
- Department of Pathology, Seoul National University College of Medicine, Seoul National University Hospital, Seoul, Republic of Korea
| | - Han-Soo Kim
- Department of Orthopedic Surgery, Seoul National University College of Medicine, Seoul National University Hospital, Seoul, Republic of Korea
| | - Hyoung Jin Kang
- Department of Pediatrics, Seoul National University College of Medicine, Seoul National University Children's Hospital, Seoul, Republic of Korea
- Seoul National University Cancer Research Institute, Seoul, Republic of Korea
- Wide River Institute of Immunology, Hongcheon, Republic of Korea
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6
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Neuberger A, Sobolevsky AI. Molecular pharmacology of the onco-TRP channel TRPV6. Channels (Austin) 2023; 17:2266669. [PMID: 37838981 PMCID: PMC10578198 DOI: 10.1080/19336950.2023.2266669] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2023] [Accepted: 09/29/2023] [Indexed: 10/17/2023] Open
Abstract
TRPV6, a representative of the vanilloid subfamily of TRP channels, serves as the principal calcium uptake channel in the gut. Dysregulation of TRPV6 results in disturbed calcium homeostasis leading to a variety of human diseases, including many forms of cancer. Inhibitors of this oncochannel are therefore particularly needed. In this review, we provide an overview of recent advances in structural pharmacology that uncovered the molecular mechanisms of TRPV6 inhibition by a variety of small molecules, including synthetic and natural, plant-derived compounds as well as some prospective and clinically approved drugs.
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Affiliation(s)
- Arthur Neuberger
- Department of Biochemistry and Molecular Biophysics, Columbia University, New York, NY, USA
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7
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Mazarico-Altisent I, Capel I, Baena N, Bella-Cueto MR, Barcons S, Guirao X, Pareja R, Muntean A, Arsentales V, Caixàs A, Rigla M. Genetic testing for familial hyperparathyroidism: clinical-genetic profile in a Mediterranean cohort. Front Endocrinol (Lausanne) 2023; 14:1244361. [PMID: 37810884 PMCID: PMC10558207 DOI: 10.3389/fendo.2023.1244361] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/22/2023] [Accepted: 09/04/2023] [Indexed: 10/10/2023] Open
Abstract
Background Approximately 10% of primary hyperparathyroidism cases are hereditary, due to germline mutations in certain genes. Although clinically relevant, a systematized genetic diagnosis is missing due to a lack of firm evidence regarding individuals to test and which genes to evaluate. Methods A customized gene panel (AIP, AP2S1, CASR, CDC73, CDKN1A, CDKN1B, CDKN2B, CDKN2C, GCM2, GNA11, MEN1, PTH, RET, and TRPV6) was performed in 40 patients from the Mediterranean area with suspected familial hyperparathyroidism (≤45 years of age, family history, high-risk histology, associated tumour, multiglandular disease, or recurrent hyperparathyroidism). We aimed to determine the prevalence of germline variants in these patients, to clinically characterize the probands and their relatives, and to compare disease severity in carriers versus those with a negative genetic test. Results Germline variants were observed in 9/40 patients (22.5%): 2 previously unknown pathogenic/likely pathogenic variants of CDKN1B (related to MEN4), 1 novel variant of uncertain significance of CDKN2C, 4 variants of CASR (3 pathogenic/likely pathogenic variants and 1 variant of uncertain significance), and 2 novel variants of uncertain significance of TRPV6. Familial segregation studies allowed diagnosis and early treatment of PHPT in first-degree relatives of probands. Conclusion The observed prevalence of germline variants in the Mediterranean cohort under study was remarkable and slightly higher than that seen in other populations. Genetic screening for suspected familial hyperparathyroidism allows the early diagnosis and treatment of PHPT and other related comorbidities. We recommend genetic testing for patients with primary hyperparathyroidism who present with high-risk features.
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Affiliation(s)
- Isabel Mazarico-Altisent
- Endocrinology and Nutrition Department, Parc Taulí University Hospital, Institut d’Investigació i Innovació Parc Taulí (I3PT), Medicine Department, Universitat Autònoma de Barcelona, Sabadell, Barcelona, Spain
| | - Ismael Capel
- Endocrinology and Nutrition Department, Parc Taulí University Hospital, Institut d’Investigació i Innovació Parc Taulí (I3PT), Medicine Department, Universitat Autònoma de Barcelona, Sabadell, Barcelona, Spain
| | - Neus Baena
- Genetic Department, Parc Taulí University Hospital, Institut d’Investigació i Innovació Parc Taulí (I3PT), Medicine Department, Universitat Autònoma de Barcelona, Sabadell, Barcelona, Spain
| | - Maria Rosa Bella-Cueto
- Pathology Department, Parc Taulí University Hospital, Institut d’Investigació i Innovació Parc Taulí (I3PT), Medicine Department, Universitat Autònoma de Barcelona, Sabadell, Barcelona, Spain
| | - Santi Barcons
- Surgery Department, Parc Taulí University Hospital, Institut d’Investigació i Innovació Parc Taulí (I3PT), Medicine Department, Universitat Autònoma de Barcelona, Sabadell, Barcelona, Spain
| | - Xavier Guirao
- Surgery Department, Parc Taulí University Hospital, Institut d’Investigació i Innovació Parc Taulí (I3PT), Medicine Department, Universitat Autònoma de Barcelona, Sabadell, Barcelona, Spain
| | - Rocío Pareja
- Endocrinology and Nutrition Department, Parc Taulí University Hospital, Institut d’Investigació i Innovació Parc Taulí (I3PT), Medicine Department, Universitat Autònoma de Barcelona, Sabadell, Barcelona, Spain
| | - Andreea Muntean
- Endocrinology and Nutrition Department, Parc Taulí University Hospital, Institut d’Investigació i Innovació Parc Taulí (I3PT), Medicine Department, Universitat Autònoma de Barcelona, Sabadell, Barcelona, Spain
| | - Valeria Arsentales
- Endocrinology and Nutrition Department, Parc Taulí University Hospital, Institut d’Investigació i Innovació Parc Taulí (I3PT), Medicine Department, Universitat Autònoma de Barcelona, Sabadell, Barcelona, Spain
| | - Assumpta Caixàs
- Endocrinology and Nutrition Department, Parc Taulí University Hospital, Institut d’Investigació i Innovació Parc Taulí (I3PT), Medicine Department, Universitat Autònoma de Barcelona, Sabadell, Barcelona, Spain
| | - Mercedes Rigla
- Endocrinology and Nutrition Department, Parc Taulí University Hospital, Institut d’Investigació i Innovació Parc Taulí (I3PT), Medicine Department, Universitat Autònoma de Barcelona, Sabadell, Barcelona, Spain
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8
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Lee BH, De Jesús Pérez JJ, Moiseenkova-Bell V, Rohacs T. Structural basis of the activation of TRPV5 channels by long-chain acyl-Coenzyme-A. Nat Commun 2023; 14:5883. [PMID: 37735536 PMCID: PMC10514044 DOI: 10.1038/s41467-023-41577-z] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2022] [Accepted: 09/10/2023] [Indexed: 09/23/2023] Open
Abstract
Long-chain acyl-coenzyme A (LC-CoA) is a crucial metabolic intermediate that plays important cellular regulatory roles, including activation and inhibition of ion channels. The structural basis of ion channel regulation by LC-CoA is not known. Transient receptor potential vanilloid 5 and 6 (TRPV5 and TRPV6) are epithelial calcium-selective ion channels. Here, we demonstrate that LC-CoA activates TRPV5 and TRPV6 in inside-out patches, and both exogenously supplied and endogenously produced LC-CoA can substitute for the natural ligand phosphatidylinositol 4,5-bisphosphate (PI(4,5)P2) in maintaining channel activity in intact cells. Utilizing cryo-electron microscopy, we determined the structure of LC-CoA-bound TRPV5, revealing an open configuration with LC-CoA occupying the same binding site as PI(4,5)P2 in previous studies. This is consistent with our finding that PI(4,5)P2 could not further activate the channels in the presence of LC-CoA. Our data provide molecular insights into ion channel regulation by a metabolic signaling molecule.
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Affiliation(s)
- Bo-Hyun Lee
- Department of Pharmacology, Physiology and Neuroscience, Rutgers, New Jersey Medical School, Newark, NJ, USA
- Department of Physiology, Gyeongsang National University Medical School, Jinju, Korea
| | - José J De Jesús Pérez
- Department of Systems Pharmacology and Translational Therapeutics, University of Pennsylvania, Philadelphia, PA, USA
| | - Vera Moiseenkova-Bell
- Department of Systems Pharmacology and Translational Therapeutics, University of Pennsylvania, Philadelphia, PA, USA.
| | - Tibor Rohacs
- Department of Pharmacology, Physiology and Neuroscience, Rutgers, New Jersey Medical School, Newark, NJ, USA.
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9
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Neuberger A, Trofimov YA, Yelshanskaya MV, Khau J, Nadezhdin KD, Khosrof LS, Krylov NA, Efremov RG, Sobolevsky AI. Molecular pathway and structural mechanism of human oncochannel TRPV6 inhibition by the phytocannabinoid tetrahydrocannabivarin. Nat Commun 2023; 14:4630. [PMID: 37532722 PMCID: PMC10397291 DOI: 10.1038/s41467-023-40362-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2022] [Accepted: 07/25/2023] [Indexed: 08/04/2023] Open
Abstract
The calcium-selective oncochannel TRPV6 is an important driver of cell proliferation in human cancers. Despite increasing interest of pharmacological research in developing synthetic inhibitors of TRPV6, natural compounds acting at this channel have been largely neglected. On the other hand, pharmacokinetics of natural small-molecule antagonists optimized by nature throughout evolution endows these compounds with a medicinal potential to serve as potent and safe next-generation anti-cancer drugs. Here we report the structure of human TRPV6 in complex with tetrahydrocannabivarin (THCV), a natural cannabinoid inhibitor extracted from Cannabis sativa. We use cryo-electron microscopy combined with electrophysiology, calcium imaging, mutagenesis, and molecular dynamics simulations to identify THCV binding sites in the portals that connect the membrane environment surrounding the protein to the central cavity of the channel pore and to characterize the allosteric mechanism of TRPV6 inhibition. We also propose the molecular pathway taken by THCV to reach its binding site. Our study provides a foundation for the development of new TRPV6-targeting drugs.
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Affiliation(s)
- Arthur Neuberger
- Department of Biochemistry and Molecular Biophysics, Columbia University, New York, NY, USA
| | - Yury A Trofimov
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia
| | - Maria V Yelshanskaya
- Department of Biochemistry and Molecular Biophysics, Columbia University, New York, NY, USA
| | - Jeffrey Khau
- Department of Biochemistry and Molecular Biophysics, Columbia University, New York, NY, USA
| | - Kirill D Nadezhdin
- Department of Biochemistry and Molecular Biophysics, Columbia University, New York, NY, USA
| | - Lena S Khosrof
- Department of Biochemistry and Molecular Biophysics, Columbia University, New York, NY, USA
| | - Nikolay A Krylov
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia
| | - Roman G Efremov
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia
| | - Alexander I Sobolevsky
- Department of Biochemistry and Molecular Biophysics, Columbia University, New York, NY, USA.
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10
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Neuberger A, Trofimov YA, Yelshanskaya MV, Nadezhdin KD, Krylov NA, Efremov RG, Sobolevsky AI. Structural mechanism of human oncochannel TRPV6 inhibition by the natural phytoestrogen genistein. Nat Commun 2023; 14:2659. [PMID: 37160865 PMCID: PMC10169861 DOI: 10.1038/s41467-023-38352-5] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2022] [Accepted: 04/27/2023] [Indexed: 05/11/2023] Open
Abstract
Calcium-selective oncochannel TRPV6 is the major driver of cell proliferation in human cancers. While significant effort has been invested in the development of synthetic TRPV6 inhibitors, natural channel blockers have been largely neglected. Here we report the structure of human TRPV6 in complex with the plant-derived phytoestrogen genistein, extracted from Styphnolobium japonicum, that was shown to inhibit cell invasion and metastasis in cancer clinical trials. Despite the pharmacological value, the molecular mechanism of TRPV6 inhibition by genistein has remained enigmatic. We use cryo-EM combined with electrophysiology, calcium imaging, mutagenesis, and molecular dynamics simulations to show that genistein binds in the intracellular half of the TRPV6 pore and acts as an ion channel blocker and gating modifier. Genistein binding to the open channel causes pore closure and a two-fold symmetrical conformational rearrangement in the S4-S5 and S6-TRP helix regions. The unprecedented mechanism of TRPV6 inhibition by genistein uncovers new possibilities in structure-based drug design.
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Affiliation(s)
- Arthur Neuberger
- Department of Biochemistry and Molecular Biophysics, Columbia University, New York, NY, USA
| | - Yury A Trofimov
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia
| | - Maria V Yelshanskaya
- Department of Biochemistry and Molecular Biophysics, Columbia University, New York, NY, USA
| | - Kirill D Nadezhdin
- Department of Biochemistry and Molecular Biophysics, Columbia University, New York, NY, USA
| | - Nikolay A Krylov
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia
| | - Roman G Efremov
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia
| | - Alexander I Sobolevsky
- Department of Biochemistry and Molecular Biophysics, Columbia University, New York, NY, USA.
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Goma M, Hagiwara SI, Wada T, Maeyama T, Okamoto N, Ishii S, Etani Y, Masamune A. A case of early-onset idiopathic chronic pancreatitis associated with a loss-of-function TRPV6 p.R483Q variant successfully treated by pancreatic duct stenting. Clin J Gastroenterol 2023:10.1007/s12328-023-01805-x. [PMID: 37119441 DOI: 10.1007/s12328-023-01805-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/11/2023] [Accepted: 04/14/2023] [Indexed: 05/01/2023]
Abstract
Several pancreatitis-related genetic variants have been identified. Recently, the association of loss-of-function variants in the transient receptor potential cation channel subfamily V member 6 (TRPV6) gene and early-onset non-alcoholic chronic pancreatitis (CP) has been reported. However, detailed clinical presentation of the cases carrying TRPV6 variants remains largely unknown. We report a case of early CP carrying a TRPV6 variant in which recurrent attacks of pancreatitis were successfully managed by pancreatic duct stenting. A 12-year-old boy with CP was referred to our hospital for further investigation. He had experienced recurrent pancreatitis attacks since he was 11 years old. Pancreatic ductal anomalies were not identified on magnetic resonance cholangiopancreatography. Genetic analysis revealed that the patient had a loss-of-function TRPV6 c.1448G > A (p.R483Q) variant in a heterozygous form. Conservative treatments were not effective; thus, we placed pancreatic duct stent by endoscopic intervention, and the frequency of relapses have dramatically decreased. We present the first pediatric report of early CP associated with the TRPV6 variant that was successfully treated with pancreatic duct stenting. This case suggests that pancreatic duct stenting is effective in preventing the relapse of pancreatitis related to the TRPV6 variant.
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Affiliation(s)
- Mizuki Goma
- Department of Gastroenterology, Nutrition and Endocrinology, Osaka Women's and Children's Hospital, 840 Murodo-cho, Izumi, Osaka, 594-1101, Japan
| | - Shin-Ichiro Hagiwara
- Department of Gastroenterology, Nutrition and Endocrinology, Osaka Women's and Children's Hospital, 840 Murodo-cho, Izumi, Osaka, 594-1101, Japan.
| | - Tamaki Wada
- Department of Gastroenterology, Nutrition and Endocrinology, Osaka Women's and Children's Hospital, 840 Murodo-cho, Izumi, Osaka, 594-1101, Japan
| | - Takatoshi Maeyama
- Department of Gastroenterology, Nutrition and Endocrinology, Osaka Women's and Children's Hospital, 840 Murodo-cho, Izumi, Osaka, 594-1101, Japan
| | - Nobuhiko Okamoto
- Department of Medical Genetics, Osaka Women's and Children's Hospital, 840 Murodo-cho, Izumi, Osaka, 594-1101, Japan
| | - Shuji Ishii
- Department of Gastroenterology and Hepatology, Osaka General Medical Center, 3-1-56 Mandaihigashi, Sumiyoshi-ku, Osaka, 558-8558, Japan
| | - Yuri Etani
- Department of Gastroenterology, Nutrition and Endocrinology, Osaka Women's and Children's Hospital, 840 Murodo-cho, Izumi, Osaka, 594-1101, Japan
| | - Atsushi Masamune
- Division of Gastroenterology, Tohoku University Graduate School of Medicine, 1-1 Seiryo-machi, Aoba-ku, Sendai, 980-8574, Japan
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12
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Intracellular Helix-Loop-Helix Domain Modulates Inactivation Kinetics of Mammalian TRPV5 and TRPV6 Channels. Int J Mol Sci 2023; 24:ijms24054470. [PMID: 36901904 PMCID: PMC10003196 DOI: 10.3390/ijms24054470] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2022] [Revised: 02/10/2023] [Accepted: 02/17/2023] [Indexed: 03/12/2023] Open
Abstract
TRPV5 and TRPV6 are calcium-selective ion channels expressed at the apical membrane of epithelial cells. Important for systemic calcium (Ca2+) homeostasis, these channels are considered gatekeepers of this cation transcellular transport. Intracellular Ca2+ exerts a negative control over the activity of these channels by promoting inactivation. TRPV5 and TRPV6 inactivation has been divided into fast and slow phases based on their kinetics. While slow inactivation is common to both channels, fast inactivation is characteristic of TRPV6. It has been proposed that the fast phase depends on Ca2+ binding and that the slow phase depends on the binding of the Ca2+/Calmodulin complex to the internal gate of the channels. Here, by means of structural analyses, site-directed mutagenesis, electrophysiology, and molecular dynamic simulations, we identified a specific set of amino acids and interactions that determine the inactivation kinetics of mammalian TRPV5 and TRPV6 channels. We propose that the association between the intracellular helix-loop-helix (HLH) domain and the TRP domain helix (TDh) favors the faster inactivation kinetics observed in mammalian TRPV6 channels.
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Walker V, Vuister GW. Biochemistry and pathophysiology of the Transient Potential Receptor Vanilloid 6 (TRPV6) calcium channel. Adv Clin Chem 2023; 113:43-100. [PMID: 36858649 DOI: 10.1016/bs.acc.2022.11.002] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
TRPV6 is a Transient Receptor Potential Vanilloid (TRPV) cation channel with high selectivity for Ca2+ ions. First identified in 1999 in a search for the gene which mediates intestinal Ca2+ absorption, its far more extensive repertoire as a guardian of intracellular Ca2+ has since become apparent. Studies on TRPV6-deficient mice demonstrated additional important roles in placental Ca2+ transport, fetal bone development and male fertility. The first reports of inherited deficiency in newborn babies appeared in 2018, revealing its physiological importance in humans. There is currently strong evidence that TRPV6 also contributes to the pathogenesis of some common cancers. The recently reported association of TRPV6 deficiency with non-alcoholic chronic pancreatitis suggests a role in normal pancreatic function. Over time and with greater awareness of TRPV6, other disease-associations are likely to emerge. Powerful analytical tools have provided invaluable insights into the structure and operation of TRPV6. Its roles in Ca2+ signaling and carcinogenesis, and the use of channel inhibitors in cancer treatment are being intensively investigated. This review first briefly describes the biochemistry and physiology of the channel, and analytical methods used to investigate these. The focus subsequently shifts to the clinical disorders associated with abnormal expression and the underlying pathophysiology. The aims of this review are to increase awareness of this channel, and to draw together findings from a wide range of sources which may help to formulate new ideas for further studies.
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Affiliation(s)
- Valerie Walker
- Department of Clinical Biochemistry, University Hospital Southampton NHS Foundation Trust, Southampton General Hospital, Southampton, United Kingdom.
| | - Geerten W Vuister
- Department of Molecular and Cell Biology, Leicester Institute of Structural and Chemical Biology, University of Leicester, Leicester, United Kingdom
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Spix B, Castiglioni AJ, Remis NN, Flores EN, Wartenberg P, Wyatt A, Boehm U, Gudermann T, Biel M, García-Añoveros J, Grimm C. Whole-body analysis of TRPML3 (MCOLN3) expression using a GFP-reporter mouse model reveals widespread expression in secretory cells and endocrine glands. PLoS One 2022; 17:e0278848. [PMID: 36520788 PMCID: PMC10045552 DOI: 10.1371/journal.pone.0278848] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2022] [Accepted: 11/27/2022] [Indexed: 12/23/2022] Open
Abstract
TRPML3 (mucolipin 3, MCOLN3) is an endolysosomal cation channel belonging to the TRPML subfamily of transient receptor potential channels. Gain-of-function mutations in the Trpml3 gene cause deafness, circling behavior and coat color dilution in mice due to cell death of TRPML3-expressing hair cells of the inner ear or skin melanocytes, respectively. Furthermore, TRPML3 was found to play a role in the long term survival of cochlear hair cells (its absence contributing to presbycusis), in specialized giant lysosomes that neonatal (birth to weaning) enterocytes used for the uptake and digestion of maternal milk nutrients, and in the expulsion of exosome-encased bacteria such as uropathogenic E. coli, infecting bladder epithelial cells. Recently, TRPML3 was found to be expressed at high levels in alveolar macrophages and loss of TRPML3 results in a lung emphysema phenotype, confirmed in two independently engineered Trpml3 knockout lines. TRPML3 is not ubiquitously expressed like its relative TRPML1 and thus cellular expression of TRPML3 on a whole-tissue level remains, with the exceptions mentioned above, largely elusive. To overcome this problem, we generated a τGFP reporter mouse model for TRPML3 and compared expression data obtained from this model by immunofluorescence on tissue sections with immunohistochemistry using TRPML3 antibodies and in situ hybridization. We thus uncovered expression in several organs and distinct cell types. We confirmed TRPML3 expression in both neonatal and adult alveolar macrophages, in melanocytes of hair follicles and glabrous skin, in principle cells of the collecting duct of the neonatal and adult kidney, and in olfactory sensory neurons of the olfactory epithelium, including its fibres protruding to the glomeruli of the olfactory bulb. Additionally, we localized TRPML3 in several glands including parathyroid, thyroid, salivary, adrenal, and pituitary gland, testes and ovaries, suggestive of potential roles for the channel in secretion or uptake of different hormones.
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Affiliation(s)
- Barbara Spix
- Walther Straub Institute of Pharmacology and Toxicology, Faculty of Medicine, Ludwig-Maximilians-University, Munich, Germany
| | - Andrew J. Castiglioni
- Department of Anesthesiology, Northwestern University Feinberg School of Medicine, Chicago, Illinois, United States of America
| | - Natalie N. Remis
- Department of Anesthesiology, Northwestern University Feinberg School of Medicine, Chicago, Illinois, United States of America
- Integrated Graduate Program in the Life Sciences (IGP), Northwestern University Feinberg School of Medicine, Chicago, Illinois, United States of America
| | - Emma N. Flores
- Department of Anesthesiology, Northwestern University Feinberg School of Medicine, Chicago, Illinois, United States of America
- Northwestern University Interdepartmental Neuroscience (NUIN) graduate program, Chicago, Illinois, United States of America
| | - Philipp Wartenberg
- Center for Molecular Signaling (PZMS), Experimental Pharmacology, Saarland University, Homburg, Germany
| | - Amanda Wyatt
- Center for Molecular Signaling (PZMS), Experimental Pharmacology, Saarland University, Homburg, Germany
| | - Ulrich Boehm
- Center for Molecular Signaling (PZMS), Experimental Pharmacology, Saarland University, Homburg, Germany
| | - Thomas Gudermann
- Walther Straub Institute of Pharmacology and Toxicology, Faculty of Medicine, Ludwig-Maximilians-University, Munich, Germany
| | - Martin Biel
- Department of Pharmacy, Ludwig-Maximilians-University, Munich, Germany
| | - Jaime García-Añoveros
- Department of Anesthesiology, Northwestern University Feinberg School of Medicine, Chicago, Illinois, United States of America
- Integrated Graduate Program in the Life Sciences (IGP), Northwestern University Feinberg School of Medicine, Chicago, Illinois, United States of America
- Northwestern University Interdepartmental Neuroscience (NUIN) graduate program, Chicago, Illinois, United States of America
- Departments of Neurology and Neuroscience, and Hugh Knowles Center for Clinical and Basic Science in Hearing and Its Disorders, Northwestern University Feinberg School of Medicine, Chicago, Illinois, United States of America
| | - Christian Grimm
- Walther Straub Institute of Pharmacology and Toxicology, Faculty of Medicine, Ludwig-Maximilians-University, Munich, Germany
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Rohacs T, Fluck EC, De Jesús-Pérez JJ, Moiseenkova-Bell VY. What structures did, and did not, reveal about the function of the epithelial Ca 2+ channels TRPV5 and TRPV6. Cell Calcium 2022; 106:102620. [PMID: 35834842 DOI: 10.1016/j.ceca.2022.102620] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2022] [Revised: 06/29/2022] [Accepted: 07/01/2022] [Indexed: 12/15/2022]
Abstract
Transient Receptor Potential Vanilloid 5 and 6 (TRPV5 and TRPV6) are Ca2+ selective epithelial ion channels. They are the products of a relatively recent gene duplication in mammals, and have high sequence homology to each other. Their functional properties are also much more similar to each other than to other members of the TRPV subfamily. They are both constitutively active, and this activity depends on the endogenous cofactor phosphatidylinositol 4,5-bisphosphate [PI(4,5)P2]. Both channels undergo Ca2+-induced inactivation, which is mediated by direct binding of the ubiquitous Ca2+ binding protein calmodulin (CaM) to the channels, and by a decrease in PI(4,5)P2 levels by Ca2+ -induced activation of phospholipase C (PLC). Recent cryo electron microscopy (cryo-EM) and X-ray crystallography structures provided detailed structural information for both TRPV5 and TRPV6. This review will discuss this structural information in the context of the function of these channels focusing on the mechanism of CaM inhibition, activation by PI(4,5)P2 and binding of pharmacological modulators.
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Affiliation(s)
- Tibor Rohacs
- Department of Pharmacology, Physiology and Neuroscience, New Jersey Medical School, Rutgers University, Newark, New Jersey 07103, USA.
| | - Edwin C Fluck
- Department of Systems Pharmacology and Translational Therapeutics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
| | - José J De Jesús-Pérez
- Department of Systems Pharmacology and Translational Therapeutics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
| | - Vera Y Moiseenkova-Bell
- Department of Systems Pharmacology and Translational Therapeutics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA.
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Wang L, Cai R, Chen XZ, Peng JB. Molecular insights into the structural and dynamical changes of calcium channel TRPV6 induced by its interaction with phosphatidylinositol 4,5-bisphosphate. J Biomol Struct Dyn 2022:1-10. [PMID: 35950523 PMCID: PMC9918602 DOI: 10.1080/07391102.2022.2109752] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/15/2022]
Abstract
Transient receptor potential vanilloid subfamily member 6 (TRPV6) is an epithelial calcium channel that regulates the initial step of the transcellular calcium transport pathway. TRPV6 is expressed in the kidney, intestine, placenta, and other tissues, and the dysregulation of the channel is implicated in several human cancers. It has been reported that phosphatidylinositol 4,5-bisphosphate (PIP2) activates TRPV6 and its close homologue TRPV5; however, the underlying molecular mechanism is less clear. Recently, a structure of rabbit TRPV5 in complex with dioctanoyl (diC8) PIP2, a soluble form of PIP2, was determined by cryo-electron microscopy. Based on this structure, the structural model of human TRPV6 with PIP2 was set up, and then molecular dynamics simulations were performed for TRPV6 with and without PIP2. Simulation results show that the positively charged residues responsible for TRPV5 binding of diC8 PIP2 are conserved in the interactions between TRPV6 and PIP2. The binding of PIP2 to TRPV6 increases the distance between the diagonally opposed residues D542 in the selectivity filter and that between the diagonally opposed M578 residues in the lower gate of TRPV6. A secondary structural analysis reveals that residues M578 in TRPV6 undergo structural and position changes during the binding of PIP2 with TRPV6. In addition, principal component analysis indicates that the binding of PIP2 increases the dynamical motions of both the selectivity filter and the lower gate of TRPV6. These changes induced by PIP2 favor the channel opening. Thus, this study provides a basis for understanding the mechanism underlying the PIP2-induced TRPV6 channel activation.Communicated by Ramaswamy H. Sarma.
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Affiliation(s)
- Lingyun Wang
- Division of Nephrology, Department of Medicine, Nephrology Research and Training Center, University of Alabama at Birmingham, Birmingham, AL 35294
| | - Ruiqi Cai
- Membrane Protein Disease Research Group, Department of Physiology, Faculty of Medicine and Dentistry, University of Alberta, T6G 2H7 Edmonton, AB, Canada
| | - Xing-Zhen Chen
- Membrane Protein Disease Research Group, Department of Physiology, Faculty of Medicine and Dentistry, University of Alberta, T6G 2H7 Edmonton, AB, Canada
| | - Ji-Bin Peng
- Division of Nephrology, Department of Medicine, Nephrology Research and Training Center, University of Alabama at Birmingham, Birmingham, AL 35294,Department of Urology, University of Alabama at Birmingham, Birmingham, AL 35294,To whom correspondence should be addressed:
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TRPV6 Regulation by Cis-22a and Cholesterol. Biomolecules 2022; 12:biom12060804. [PMID: 35740929 PMCID: PMC9221249 DOI: 10.3390/biom12060804] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2022] [Revised: 06/03/2022] [Accepted: 06/05/2022] [Indexed: 02/04/2023] Open
Abstract
The highly calcium-selective transient receptor potential vanilloid-type channel TRPV6 is important for epithelial Ca2+ transport. Proper regulation of the inherently constitutively active TRPV6 channels is intricate in preserving Ca2+ homeostasis, whereby structural and functional data suggest that lipids hold an essential role. Altered expression levels or specific TRPV6 mutations may lead to diseases, hence, TRPV6 represents an interesting target for pharmacological modulation. Recent cryo-EM data identified that the specific TRPV6 blocker cis-22a binds, apart from the pore, to a site within the tetrameric channel that largely matches a lipid binding pocket, LBS-2. Therein, cis-22a may replace a lipid such as cholesterol that is bound in the open state. Based on site-directed mutagenesis and functional recordings, we identified and characterized a series of residues within LBS-2 that are essential for TRPV6 inhibition by cis-22a. Additionally, we investigated the modulatory potential of diverse cholesterol depletion efforts on TRPV6 activity. While LBS-2 mutants exhibited altered maximum currents, slow Ca2+-dependent inactivation (SCDI) as well as less inhibition by cis-22a, TRPV6 activity was resistant to cholesterol depletion. Hence, lipids other than cholesterol may predominate TRPV6 regulation when the channel is expressed in HEK293 cells.
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Khattar V, Wang L, Peng JB. Calcium selective channel TRPV6: Structure, function, and implications in health and disease. Gene 2022; 817:146192. [PMID: 35031425 PMCID: PMC8950124 DOI: 10.1016/j.gene.2022.146192] [Citation(s) in RCA: 22] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2020] [Revised: 12/20/2021] [Accepted: 01/07/2022] [Indexed: 12/14/2022]
Abstract
Calcium-selective channel TRPV6 (Transient Receptor Potential channel family, Vanilloid subfamily member 6) belongs to the TRP family of cation channels and plays critical roles in transcellular calcium (Ca2+) transport, reuptake of Ca2+ into cells, and maintaining a local low Ca2+ environment for certain biological processes. Recent crystal and cryo-electron microscopy-based structures of TRPV6 have revealed mechanistic insights on how the protein achieves Ca2+ selectivity, permeation, and inactivation by calmodulin. The TRPV6 protein is expressed in a range of epithelial tissues such as the intestine, kidney, placenta, epididymis, and exocrine glands such as the pancreas, prostate and salivary, sweat, and mammary glands. The TRPV6 gene is a direct transcriptional target of the active form of vitamin D and is efficiently regulated to meet the body's need for Ca2+ demand. In addition, TRPV6 is also regulated by the level of dietary Ca2+ and under physiological conditions such as pregnancy and lactation. Genetic models of loss of function in TRPV6 display hypercalciuria, decreased bone marrow density, deficient weight gain, reduced fertility, and in some cases alopecia. The models also reveal that the channel plays an indispensable role in maintaining maternal-fetal Ca2+ transport and low Ca2+ environment in the epididymal lumen that is critical for male fertility. Most recently, loss of function mutations in TRPV6 gene is linked to transient neonatal hyperparathyroidism and early onset chronic pancreatitis. TRPV6 is overexpressed in a wide range of human malignancies and its upregulation is strongly correlated to tumor aggressiveness, metastasis, and poor survival in selected cancers. This review summarizes the current state of knowledge on the expression, structure, biophysical properties, function, polymorphisms, and regulation of TRPV6. The aberrant expression, polymorphisms, and dysfunction of this protein linked to human diseases are also discussed.
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Affiliation(s)
- Vinayak Khattar
- Division of Nephrology, Department of Medicine, Nephrology Research and Training Center, Department of Urology, University of Alabama at Birmingham, Birmingham, AL 35294, USA
| | - Lingyun Wang
- Division of Nephrology, Department of Medicine, Nephrology Research and Training Center, Department of Urology, University of Alabama at Birmingham, Birmingham, AL 35294, USA
| | - Ji-Bin Peng
- Division of Nephrology, Department of Medicine, Nephrology Research and Training Center, Department of Urology, University of Alabama at Birmingham, Birmingham, AL 35294, USA.
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Gorvin CM. Genetic causes of neonatal and infantile hypercalcaemia. Pediatr Nephrol 2022; 37:289-301. [PMID: 33990852 PMCID: PMC8816529 DOI: 10.1007/s00467-021-05082-z] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/11/2021] [Revised: 03/25/2021] [Accepted: 04/06/2021] [Indexed: 12/02/2022]
Abstract
The causes of hypercalcaemia in the neonate and infant are varied, and often distinct from those in older children and adults. Hypercalcaemia presents clinically with a range of symptoms including failure to thrive, poor feeding, constipation, polyuria, irritability, lethargy, seizures and hypotonia. When hypercalcaemia is suspected, an accurate diagnosis will require an evaluation of potential causes (e.g. family history) and assessment for physical features (such as dysmorphology, or subcutaneous fat deposits), as well as biochemical measurements, including total and ionised serum calcium, serum phosphate, creatinine and albumin, intact parathyroid hormone (PTH), vitamin D metabolites and urinary calcium, phosphate and creatinine. The causes of neonatal hypercalcaemia can be classified into high or low PTH disorders. Disorders associated with high serum PTH include neonatal severe hyperparathyroidism, familial hypocalciuric hypercalcaemia and Jansen's metaphyseal chondrodysplasia. Conditions associated with low serum PTH include idiopathic infantile hypercalcaemia, Williams-Beuren syndrome and inborn errors of metabolism, including hypophosphatasia. Maternal hypocalcaemia and dietary factors and several rare endocrine disorders can also influence neonatal serum calcium levels. This review will focus on the common causes of hypercalcaemia in neonates and young infants, considering maternal, dietary, and genetic causes of calcium dysregulation. The clinical presentation and treatment of patients with these disorders will be discussed.
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Affiliation(s)
- Caroline M. Gorvin
- Institute of Metabolism and Systems Research and Centre for Endocrinology, Diabetes and Metabolism, University of Birmingham, Birmingham, B15 2TT UK ,Centre of Membrane Proteins and Receptors (COMPARE), Universities of Birmingham and Nottingham, Birmingham, B15 2TT UK
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Fecher-Trost C, Wolske K, Wesely C, Löhr H, Klawitter DS, Weissgerber P, Gradhand E, Burren CP, Mason AE, Winter M, Wissenbach U. Mutations That Affect the Surface Expression of TRPV6 Are Associated with the Upregulation of Serine Proteases in the Placenta of an Infant. Int J Mol Sci 2021; 22:12694. [PMID: 34884497 PMCID: PMC8657554 DOI: 10.3390/ijms222312694] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2021] [Revised: 11/18/2021] [Accepted: 11/22/2021] [Indexed: 02/07/2023] Open
Abstract
Recently, we reported a case of an infant with neonatal severe under-mineralizing skeletal dysplasia caused by mutations within both alleles of the TRPV6 gene. One mutation results in an in frame stop codon (R510stop) that leads to a truncated, nonfunctional TRPV6 channel, and the second in a point mutation (G660R) that, surprisingly, does not affect the Ca2+ permeability of TRPV6. We mimicked the subunit composition of the unaffected heterozygous parent and child by coexpressing the TRPV6 G660R and R510stop mutants and combinations with wild type TRPV6. We show that both the G660R and R510stop mutant subunits are expressed and result in decreased calcium uptake, which is the result of the reduced abundancy of functional TRPV6 channels within the plasma membrane. We compared the proteomic profiles of a healthy placenta with that of the diseased infant and detected, exclusively in the latter two proteases, HTRA1 and cathepsin G. Our results implicate that the combination of the two mutant TRPV6 subunits, which are expressed in the placenta of the diseased child, is responsible for the decreased calcium uptake, which could explain the skeletal dysplasia. In addition, placental calcium deficiency also appears to be associated with an increase in the expression of proteases.
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Affiliation(s)
- Claudia Fecher-Trost
- Experimental and Clinical Pharmacology and Toxicology, Center for Molecular Signaling (PZMS), Saarland University, Buildings 61.4 and 46, 66421 Homburg, Germany; (C.F.-T.); (K.W.); (C.W.); (H.L.); (D.S.K.); (P.W.); (M.W.)
| | - Karin Wolske
- Experimental and Clinical Pharmacology and Toxicology, Center for Molecular Signaling (PZMS), Saarland University, Buildings 61.4 and 46, 66421 Homburg, Germany; (C.F.-T.); (K.W.); (C.W.); (H.L.); (D.S.K.); (P.W.); (M.W.)
| | - Christine Wesely
- Experimental and Clinical Pharmacology and Toxicology, Center for Molecular Signaling (PZMS), Saarland University, Buildings 61.4 and 46, 66421 Homburg, Germany; (C.F.-T.); (K.W.); (C.W.); (H.L.); (D.S.K.); (P.W.); (M.W.)
| | - Heidi Löhr
- Experimental and Clinical Pharmacology and Toxicology, Center for Molecular Signaling (PZMS), Saarland University, Buildings 61.4 and 46, 66421 Homburg, Germany; (C.F.-T.); (K.W.); (C.W.); (H.L.); (D.S.K.); (P.W.); (M.W.)
| | - Daniel S. Klawitter
- Experimental and Clinical Pharmacology and Toxicology, Center for Molecular Signaling (PZMS), Saarland University, Buildings 61.4 and 46, 66421 Homburg, Germany; (C.F.-T.); (K.W.); (C.W.); (H.L.); (D.S.K.); (P.W.); (M.W.)
| | - Petra Weissgerber
- Experimental and Clinical Pharmacology and Toxicology, Center for Molecular Signaling (PZMS), Saarland University, Buildings 61.4 and 46, 66421 Homburg, Germany; (C.F.-T.); (K.W.); (C.W.); (H.L.); (D.S.K.); (P.W.); (M.W.)
- Transgenic Technologies, Center for Molecular Signaling (PZMS), Saarland University, Building 61.4, 66421 Homburg, Germany
| | - Elise Gradhand
- Kinder- und Perinatalpathologie Dr. Senckenberg, Institut für Pathologie Universitätsklinikum Frankfurt/Main Theodor-Stern-Kai 7, 60590 Frankfurt, Germany;
| | - Christine P. Burren
- Department of Translational Health Sciences, Bristol Medical School, University of Bristol, University Hospitals Bristol and Weston NHS Foundation Trust, Upper Maudlin St, Bristol BS2 8BJ, UK;
| | - Anna E. Mason
- Histopathology Department, Aneurin Bevan University Health Board, Royal Gwent Hospital, Cardiff NP20 2UB, UK;
| | - Manuel Winter
- Experimental and Clinical Pharmacology and Toxicology, Center for Molecular Signaling (PZMS), Saarland University, Buildings 61.4 and 46, 66421 Homburg, Germany; (C.F.-T.); (K.W.); (C.W.); (H.L.); (D.S.K.); (P.W.); (M.W.)
| | - Ulrich Wissenbach
- Experimental and Clinical Pharmacology and Toxicology, Center for Molecular Signaling (PZMS), Saarland University, Buildings 61.4 and 46, 66421 Homburg, Germany; (C.F.-T.); (K.W.); (C.W.); (H.L.); (D.S.K.); (P.W.); (M.W.)
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Structural mechanisms of TRPV6 inhibition by ruthenium red and econazole. Nat Commun 2021; 12:6284. [PMID: 34725357 PMCID: PMC8560856 DOI: 10.1038/s41467-021-26608-x] [Citation(s) in RCA: 31] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2021] [Accepted: 10/14/2021] [Indexed: 11/26/2022] Open
Abstract
TRPV6 is a calcium-selective ion channel implicated in epithelial Ca2+ uptake. TRPV6 inhibitors are needed for the treatment of a broad range of diseases associated with disturbed calcium homeostasis, including cancers. Here we combine cryo-EM, calcium imaging, and mutagenesis to explore molecular bases of human TRPV6 inhibition by the antifungal drug econazole and the universal ion channel blocker ruthenium red (RR). Econazole binds to an allosteric site at the channel’s periphery, where it replaces a lipid. In contrast, RR inhibits TRPV6 by binding in the middle of the ion channel’s selectivity filter and plugging its pore like a bottle cork. Despite different binding site locations, both inhibitors induce similar conformational changes in the channel resulting in closure of the gate formed by S6 helices bundle crossing. The uncovered molecular mechanisms of TRPV6 inhibition can guide the design of a new generation of clinically useful inhibitors. TRPV6 is a calcium-selective ion channel that is involved in numerous calcium-dependent physiological processes and it is of interest as a potential drug target. Here, the authors present the cryo-EM structures of human TRPV6 with the bound inhibitors ruthenium red and the antifungal drug econazole and discuss their inhibition mechanisms.
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Wartenberg P, Lux F, Busch K, Fecher-Trost C, Flockerzi V, Krasteva-Christ G, Boehm U, Weissgerber P. A TRPV6 expression atlas for the mouse. Cell Calcium 2021; 100:102481. [PMID: 34628109 DOI: 10.1016/j.ceca.2021.102481] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2021] [Revised: 09/03/2021] [Accepted: 09/27/2021] [Indexed: 01/01/2023]
Abstract
The transient receptor potential vanilloid 6 (TRPV6) channel is highly Ca2+-selective and has been implicated in mediating transcellular Ca2+ transport and thus maintaining the Ca2+ balance in the body. To characterize its physiological function(s), a detailed expression profile of the TRPV6 channel throughout the body is essential. Capitalizing on a recently established murine Trpv6-reporter strain, we identified primary TRPV6 channel-expressing cells in an organism-wide manner. In a complementary experimental approach, we characterized TRPV6 expression in different tissues of wild-type mice by TRPV6 immunoprecipitation (IP) followed by mass spectrometry analysis and correlated these data with the reporter gene expression. Taken together, we present a TRPV6 expression atlas throughout the entire body of juvenile and adult mice, providing a novel resource to investigate the role of TRPV6 channels in vivo.
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Affiliation(s)
- Philipp Wartenberg
- Department of Experimental and Clinical Pharmacology and Toxicology, Center for Molecular Signaling (PZMS), Saarland University School of Medicine, Homburg, Germany
| | - Femke Lux
- Department of Experimental and Clinical Pharmacology and Toxicology, Center for Molecular Signaling (PZMS), Saarland University School of Medicine, Homburg, Germany
| | - Kai Busch
- Department of Experimental and Clinical Pharmacology and Toxicology, Center for Molecular Signaling (PZMS), Saarland University School of Medicine, Homburg, Germany
| | - Claudia Fecher-Trost
- Department of Experimental and Clinical Pharmacology and Toxicology, Center for Molecular Signaling (PZMS), Saarland University School of Medicine, Homburg, Germany
| | - Veit Flockerzi
- Department of Experimental and Clinical Pharmacology and Toxicology, Center for Molecular Signaling (PZMS), Saarland University School of Medicine, Homburg, Germany
| | | | - Ulrich Boehm
- Department of Experimental and Clinical Pharmacology and Toxicology, Center for Molecular Signaling (PZMS), Saarland University School of Medicine, Homburg, Germany
| | - Petra Weissgerber
- Department of Experimental and Clinical Pharmacology and Toxicology, Center for Molecular Signaling (PZMS), Saarland University School of Medicine, Homburg, Germany.
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Auto-inhibitory intramolecular S5/S6 interaction in the TRPV6 channel regulates breast cancer cell migration and invasion. Commun Biol 2021; 4:990. [PMID: 34413465 PMCID: PMC8376870 DOI: 10.1038/s42003-021-02521-3] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2021] [Accepted: 08/04/2021] [Indexed: 11/09/2022] Open
Abstract
TRPV6, a Ca-selective channel, is abundantly expressed in the placenta, intestine, kidney and bone marrow. TRPV6 is vital to Ca homeostasis and its defective expression or function is linked to transient neonatal hyperparathyroidism, Lowe syndrome/Dent disease, renal stone, osteoporosis and cancers. The fact that the molecular mechanism underlying the function and regulation of TRPV6 is still not well understood hampers, in particular, the understanding of how TRPV6 contributes to breast cancer development. By electrophysiology and Ca imaging in Xenopus oocytes and cancer cells, molecular biology and numerical simulation, here we reveal an intramolecular S5/S6 helix interaction in TRPV6 that is functionally autoinhibitory and is mediated by the R532:D620 bonding. Predicted pathogenic mutation R532Q within S5 disrupts the S5/S6 interaction leading to gain-of-function of the channel, which promotes breast cancer cell progression through strengthening of the TRPV6/PI3K interaction, activation of a PI3K/Akt/GSK-3β cascade, and up-regulation of epithelial-mesenchymal transition and anti-apoptosis.
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24
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Comments on the evolution of TRPV6. Ann Anat 2021; 238:151753. [PMID: 33964462 DOI: 10.1016/j.aanat.2021.151753] [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: 03/24/2021] [Revised: 04/09/2021] [Accepted: 04/09/2021] [Indexed: 10/21/2022]
Abstract
It is well known that not all biological findings derived from animals can be directly applied to humans. The TRPV6 protein may serve as an example which highlights these inter-species differences as an example of parallel evolutionary pathways. TRPV6 (and TRPV5) belong to a family of ion channels from the transient receptor potential group but are selectively permeable for Ca2+, in contrast to other members of the family. Sequences with recognizable similarity to TRPV6 can already be found in archaebacteria. These ancient sequences show clear similarity to the ion-conducting pore of TRPV6. Over the course of evolution, the duplication of the TRPV6 gene gave rise to TRPV5. Duplications of the complete genome as well as subsequent loss of genetic material have led to a variety of different TRPV5/6 combinations. In addition, there is an N-terminal extension of the protein in placental animals. This extension causes translation of TRPV6 to be initiated from an ACG codon. Inactivation of one TRPV6 allele can be correlated with alcohol-independent pancreatitis in humans while inactivation of both alleles leads to skeletal dysplasia of newborn babies. The latter effect is not observed in mice, implying that the effects due to perturbations in TRPV6 levels are much more pronounced in humans.
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25
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Mapping the expression of transient receptor potential channels across murine placental development. Cell Mol Life Sci 2021; 78:4993-5014. [PMID: 33884443 PMCID: PMC8233283 DOI: 10.1007/s00018-021-03837-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2020] [Revised: 03/17/2021] [Accepted: 04/08/2021] [Indexed: 12/12/2022]
Abstract
Transient receptor potential (TRP) channels play prominent roles in ion homeostasis by their ability to control cation influx. Mouse placentation is governed by the processes of trophoblast proliferation, invasion, differentiation, and fusion, all of which require calcium signaling. Although certain TRP channels have been shown to contribute to maternal–fetal transport of magnesium and calcium, a role for TRP channels in specific trophoblast functions has been disregarded. Using qRT-PCR and in situ hybridisation, the spatio-temporal expression pattern of TRP channels in the mouse placenta across gestation (E10.5–E18.5) was assessed. Prominent expression was observed for Trpv2, Trpm6, and Trpm7. Calcium microfluorimetry in primary trophoblast cells isolated at E14.5 of gestation further revealed the functional activity of TRPV2 and TRPM7. Finally, comparing TRP channels expression in mouse trophoblast stem cells (mTSCs) and mouse embryonic stem cells (mESC) confirmed the specific expression of TRPV2 during placental development. Moreover, TRP channel expression was similar in mTSCs compared to primary trophoblasts and validate mTSC as a model to study TRP channels in placental development. Collectivity, our results identify a specific spatio-temporal TRP channel expression pattern in trophoblasts, suggesting a possible involvement in regulating the process of placentation.
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Zhao S, Rohacs T. The newest TRP channelopathy: Gain of function TRPM3 mutations cause epilepsy and intellectual disability. Channels (Austin) 2021; 15:386-397. [PMID: 33853504 PMCID: PMC8057083 DOI: 10.1080/19336950.2021.1908781] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Transient Receptor Potential Melastatin 3 (TRPM3) is a Ca2+ permeable nonselective cation channel, activated by heat and chemical agonists, such as the endogenous neuro-steroid Pregnenolone Sulfate (PregS) and the chemical compound CIM0216. TRPM3 is expressed in peripheral sensory neurons of the dorsal root ganglia (DRG), and its role in noxious heat sensation in mice is well established. TRPM3 is also expressed in a number of other tissues, including the brain, but its role there has been largely unexplored. Recent reports showed that two mutations in TRPM3 are associated with a developmental and epileptic encephalopathy, pointing to an important role of TRPM3 in the human brain. Subsequent reports found that the two disease-associated mutations increased basal channel activity, and sensitivity of the channel to activation by heat and chemical agonists. This review will discuss these mutations in the context of human diseases caused by mutations in other TRP channels, and in the context of the biophysical properties and physiological functions of TRPM3.
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Affiliation(s)
- Siyuan Zhao
- Department of Pharmacology, Physiology and Neuroscience, Rutgers, New Jersey Medical School, Newark, NJ, USA
| | - Tibor Rohacs
- Department of Pharmacology, Physiology and Neuroscience, Rutgers, New Jersey Medical School, Newark, NJ, USA
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27
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Ribet ABP, Ng PY, Pavlos NJ. Membrane Transport Proteins in Osteoclasts: The Ins and Outs. Front Cell Dev Biol 2021; 9:644986. [PMID: 33718388 PMCID: PMC7952445 DOI: 10.3389/fcell.2021.644986] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2020] [Accepted: 02/09/2021] [Indexed: 12/12/2022] Open
Abstract
During bone resorption, the osteoclast must sustain an extraordinarily low pH environment, withstand immense ionic pressures, and coordinate nutrient and waste exchange across its membrane to sustain its unique structural and functional polarity. To achieve this, osteoclasts are equipped with an elaborate set of membrane transport proteins (pumps, transporters and channels) that serve as molecular ‘gatekeepers’ to regulate the bilateral exchange of ions, amino acids, metabolites and macromolecules across the ruffled border and basolateral domains. Whereas the importance of the vacuolar-ATPase proton pump and chloride voltage-gated channel 7 in osteoclasts has long been established, comparatively little is known about the contributions of other membrane transport proteins, including those categorized as secondary active transporters. In this Special Issue review, we provide a contemporary update on the ‘ins and outs’ of membrane transport proteins implicated in osteoclast differentiation, function and bone homeostasis and discuss their therapeutic potential for the treatment of metabolic bone diseases.
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Affiliation(s)
- Amy B P Ribet
- Bone Biology and Disease Laboratory, School of Biomedical Sciences, The University of Western Australia, Nedlands, WA, Australia
| | - Pei Ying Ng
- Bone Biology and Disease Laboratory, School of Biomedical Sciences, The University of Western Australia, Nedlands, WA, Australia
| | - Nathan J Pavlos
- Bone Biology and Disease Laboratory, School of Biomedical Sciences, The University of Western Australia, Nedlands, WA, Australia
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Nett V, Erhardt N, Wyatt A, Wissenbach U. Human TRPV6-pathies caused by gene mutations. Biochim Biophys Acta Gen Subj 2021; 1865:129873. [PMID: 33610740 DOI: 10.1016/j.bbagen.2021.129873] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2020] [Revised: 02/11/2021] [Accepted: 02/11/2021] [Indexed: 12/22/2022]
Abstract
The TRP-family of ion channels consists of 27 members in humans. Most TRP channels are non- selective cation channels with the exception of TRPV5 and TRPV6 which exhibit a high permeability for Ca2+ ions. A functional channel is formed by 4 identical subunits [1]. A growing number of mutations are present in human TRPV6 genes which alter channel function and can lead to elevated blood levels of the parathyroid hormone accompanied by transient hyperparathyroidism. Recent publications suggest that TRPV6 mutations could also trigger non-alcoholic chronic pancreatitis. This review summarises the consequences of these mutations within the TRPV6 gene.
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Affiliation(s)
- Verena Nett
- Institut für Experimentelle und Klinische Pharmakologie und Toxikologie, Universität des Saarlandes, 66421 Homburg, Germany.
| | - Nicole Erhardt
- Institut für Experimentelle und Klinische Pharmakologie und Toxikologie, Universität des Saarlandes, 66421 Homburg, Germany.
| | - Amanda Wyatt
- Institut für Experimentelle und Klinische Pharmakologie und Toxikologie, Universität des Saarlandes, 66421 Homburg, Germany.
| | - Ulrich Wissenbach
- Institut für Experimentelle und Klinische Pharmakologie und Toxikologie, Universität des Saarlandes, 66421 Homburg, Germany.
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Saraff V, Nadar R, Shaw N. Neonatal Bone Disorders. Front Pediatr 2021; 9:602552. [PMID: 33889553 PMCID: PMC8057522 DOI: 10.3389/fped.2021.602552] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/03/2020] [Accepted: 03/08/2021] [Indexed: 11/30/2022] Open
Abstract
Neonatologists care for newborns with either an antenatal suspicion or postnatal diagnosis of bone disease. With improved ultrasound imaging techniques, more cases of neonatal bone disorders are identified antenatally and this requires further diagnostic/molecular testing either antenatally or soon after birth for confirmation of the diagnosis and facilitating subsequent management. Prompt diagnosis is vital in certain conditions where initiation of treatment is time critical and life saving. We outline an approach to diagnosis, investigation, and management of a neonate with a suspected bone disorder.
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Affiliation(s)
- Vrinda Saraff
- Institute of Applied Health Research, University of Birmingham, Birmingham, United Kingdom.,Department of Endocrinology & Diabetes, Birmingham Women's and Children's National Health Service (NHS) Foundation Trust, Birmingham, United Kingdom
| | - Ruchi Nadar
- Department of Endocrinology & Diabetes, Birmingham Women's and Children's National Health Service (NHS) Foundation Trust, Birmingham, United Kingdom
| | - Nick Shaw
- Department of Endocrinology & Diabetes, Birmingham Women's and Children's National Health Service (NHS) Foundation Trust, Birmingham, United Kingdom.,Institute of Metabolism and Systems Research, University of Birmingham, Birmingham, United Kingdom
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30
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Taylor-Miller T, Allgrove J. Endocrine Diseases of Newborn: Epidemiology, Pathogenesis, Therapeutic Options, and Outcome "Current Insights Into Disorders of Calcium and Phosphate in the Newborn". Front Pediatr 2021; 9:600490. [PMID: 33614549 PMCID: PMC7892781 DOI: 10.3389/fped.2021.600490] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/30/2020] [Accepted: 01/13/2021] [Indexed: 11/13/2022] Open
Abstract
The physiology and regulation of bone minerals in the fetus and the newborn is significantly different from children and adults. The bone minerals calcium, phosphate and magnesium are all maintained at higher concentrations in utero to achieve adequate bone accretion. This is an integral component of normal fetal development which facilitates safe neonatal transition to post-natal life. When deciphering the cause of bone mineral disorders in newborns, the potential differential diagnosis list is broad and complex, including several extremely rare conditions. Also, significant discoveries including new embryological molecular genetic transcription factors, the role of active placental mineral transport, and hormone regulation factors have changed the understanding of calcium and phosphate homeostasis in the fetus and the newborn. This article will guide clinicians through an updated review of calcium and phosphate physiology, then review specific conditions pertinent to successful neonatal care. Furthermore, with the advancement of increasingly rapid molecular genetic testing, genomics will continue to play a greater role in this area of fetal diagnostics and prognostication.
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Affiliation(s)
- Tashunka Taylor-Miller
- Department of Endocrinology and Metabolic Medicine, Great Ormond Street Hospital for Children NHS Foundation Trust, London, United Kingdom
| | - Jeremy Allgrove
- Department of Endocrinology and Metabolic Medicine, Great Ormond Street Hospital for Children NHS Foundation Trust, London, United Kingdom
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31
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Transient Receptor Potential Vanilloid 6 (TRPV6) Proteins Control the Extracellular Matrix Structure of the Placental Labyrinth. Int J Mol Sci 2020; 21:ijms21249674. [PMID: 33352987 PMCID: PMC7767235 DOI: 10.3390/ijms21249674] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2020] [Revised: 12/11/2020] [Accepted: 12/15/2020] [Indexed: 02/07/2023] Open
Abstract
Calcium-selective transient receptor potential Vanilloid 6 (TRPV6) channels are expressed in fetal labyrinth trophoblasts as part of the feto-maternal barrier, necessary for sufficient calcium supply, embryo growth, and bone development during pregnancy. Recently, we have shown a less- compact labyrinth morphology of Trpv6-deficient placentae, and reduced Ca2+ uptake of primary trophoblasts upon functional deletion of TRPV6. Trpv6-/- trophoblasts show a distinct calcium-dependent phenotype. Deep proteomic profiling of wt and Trpv6-/- primary trophoblasts using label-free quantitative mass spectrometry leads to the identification of 2778 proteins. Among those, a group of proteases, including high-temperature requirement A serine peptidase 1 (HTRA1) and different granzymes are more abundantly expressed in Trpv6-/- trophoblast lysates, whereas the extracellular matrix protein fibronectin and the fibronectin-domain-containing protein 3A (FND3A) were markedly reduced. Trpv6-/-placenta lysates contain a higher intrinsic proteolytic activity increasing fibronectin degradation. Our results show that the extracellular matrix formation of the placental labyrinth depends on TRPV6; its deletion in trophoblasts correlates with the increased expression of proteases controlling the extracellular matrix in the labyrinth during pregnancy.
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32
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Why endogenous TRPV6 currents are not detectable-what can we learn from bats? Cell Calcium 2020; 92:102302. [DOI: 10.1016/j.ceca.2020.102302] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2020] [Revised: 09/18/2020] [Accepted: 09/22/2020] [Indexed: 11/21/2022]
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33
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Bhardwaj R, Lindinger S, Neuberger A, Nadezhdin KD, Singh AK, Cunha MR, Derler I, Gyimesi G, Reymond JL, Hediger MA, Romanin C, Sobolevsky AI. Inactivation-mimicking block of the epithelial calcium channel TRPV6. SCIENCE ADVANCES 2020; 6:eabe1508. [PMID: 33246965 PMCID: PMC7695471 DOI: 10.1126/sciadv.abe1508] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/03/2020] [Accepted: 10/14/2020] [Indexed: 05/25/2023]
Abstract
Epithelial calcium channel TRPV6 plays vital roles in calcium homeostasis, and its dysregulation is implicated in multifactorial diseases, including cancers. Here, we study the molecular mechanism of selective nanomolar-affinity TRPV6 inhibition by (4-phenylcyclohexyl)piperazine derivatives (PCHPDs). We use x-ray crystallography and cryo-electron microscopy to solve the inhibitor-bound structures of TRPV6 and identify two types of inhibitor binding sites in the transmembrane region: (i) modulatory sites between the S1-S4 and pore domains normally occupied by lipids and (ii) the main site in the ion channel pore. Our structural data combined with mutagenesis, functional and computational approaches suggest that PCHPDs plug the open pore of TRPV6 and convert the channel into a nonconducting state, mimicking the action of calmodulin, which causes inactivation of TRPV6 channels under physiological conditions. This mechanism of inhibition explains the high selectivity and potency of PCHPDs and opens up unexplored avenues for the design of future-generation biomimetic drugs.
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Affiliation(s)
- Rajesh Bhardwaj
- Department of Nephrology and Hypertension and Department of Biomedical Research, University of Bern, Inselspital, Freiburgstrasse 15, CH-3010 Bern, Switzerland
| | - Sonja Lindinger
- Institute of Biophysics, Johannes Kepler University Linz, Gruberstrasse 40, 4020 Linz, Austria
| | - Arthur Neuberger
- Department of Biochemistry and Molecular Biophysics, Columbia University, 650 West 168th Street, New York, NY 10032, USA
| | - Kirill D Nadezhdin
- Department of Biochemistry and Molecular Biophysics, Columbia University, 650 West 168th Street, New York, NY 10032, USA
| | - Appu K Singh
- Department of Biochemistry and Molecular Biophysics, Columbia University, 650 West 168th Street, New York, NY 10032, USA
- Department of Biological Sciences and Bioengineering, Indian Institute of Technology, Kanpur 208016, India
| | - Micael R Cunha
- Department of Chemistry and Biochemistry, University of Bern, Freiestrasse 3, 3012 Bern, Switzerland
| | - Isabella Derler
- Institute of Biophysics, Johannes Kepler University Linz, Gruberstrasse 40, 4020 Linz, Austria
| | - Gergely Gyimesi
- Department of Nephrology and Hypertension and Department of Biomedical Research, University of Bern, Inselspital, Freiburgstrasse 15, CH-3010 Bern, Switzerland
| | - Jean-Louis Reymond
- Department of Chemistry and Biochemistry, University of Bern, Freiestrasse 3, 3012 Bern, Switzerland
| | - Matthias A Hediger
- Department of Nephrology and Hypertension and Department of Biomedical Research, University of Bern, Inselspital, Freiburgstrasse 15, CH-3010 Bern, Switzerland.
| | - Christoph Romanin
- Institute of Biophysics, Johannes Kepler University Linz, Gruberstrasse 40, 4020 Linz, Austria.
| | - Alexander I Sobolevsky
- Department of Biochemistry and Molecular Biophysics, Columbia University, 650 West 168th Street, New York, NY 10032, USA.
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34
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Cunha MR, Bhardwaj R, Carrel AL, Lindinger S, Romanin C, Parise-Filho R, Hediger MA, Reymond JL. Natural product inspired optimization of a selective TRPV6 calcium channel inhibitor. RSC Med Chem 2020; 11:1032-1040. [PMID: 33479695 PMCID: PMC7513592 DOI: 10.1039/d0md00145g] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2020] [Accepted: 06/18/2020] [Indexed: 12/25/2022] Open
Abstract
Transient receptor potential vanilloid 6 (TRPV6) is a calcium channel implicated in multifactorial diseases and overexpressed in numerous cancers. We recently reported the phenyl-cyclohexyl-piperazine cis-22a as the first submicromolar TRPV6 inhibitor. This inhibitor showed a seven-fold selectivity against the closely related calcium channel TRPV5 and no activity on store-operated calcium channels (SOC), but very significant off-target effects and low microsomal stability. Here, we surveyed analogues incorporating structural features of the natural product capsaicin and identified 3OG, a new oxygenated analog with similar potency against TRPV6 (IC50 = 0.082 ± 0.004 μM) and ion channel selectivity, but with high microsomal stability and very low off-target effects. This natural product-inspired inhibitor does not exhibit any non-specific toxicity effects on various cell lines and is proposed as a new tool compound to test pharmacological inhibition of TRPV6 mediated calcium flux in disease models.
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Affiliation(s)
- Micael Rodrigues Cunha
- Department of Chemistry and Biochemistry , University of Bern , Freiestrasse 3 , 3012 Bern , Switzerland .
- Department of Pharmacy , University of São Paulo , Prof. Lineu Prestes Avenue 580 , 05508-000 São Paulo , Brazil .
| | - Rajesh Bhardwaj
- Department of Nephrology and Hypertension , University Hospital Bern , Inselspital , 3010 Bern , Switzerland .
| | - Aline Lucie Carrel
- Department of Chemistry and Biochemistry , University of Bern , Freiestrasse 3 , 3012 Bern , Switzerland .
| | - Sonja Lindinger
- Institute of Biophysics , Johannes Kepler University Linz , Gruberstrasse 40 , 4020 Linz , Austria
| | - Christoph Romanin
- Institute of Biophysics , Johannes Kepler University Linz , Gruberstrasse 40 , 4020 Linz , Austria
| | - Roberto Parise-Filho
- Department of Pharmacy , University of São Paulo , Prof. Lineu Prestes Avenue 580 , 05508-000 São Paulo , Brazil .
| | - Matthias A Hediger
- Department of Nephrology and Hypertension , University Hospital Bern , Inselspital , 3010 Bern , Switzerland .
| | - Jean-Louis Reymond
- Department of Chemistry and Biochemistry , University of Bern , Freiestrasse 3 , 3012 Bern , Switzerland .
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Suzuki Y, Sawada H, Tokumasu T, Suzuki S, Ninomiya S, Shirai M, Mukai T, Saito CT, Nishimura G, Tominaga M. Novel TRPV6 mutations in the spectrum of transient neonatal hyperparathyroidism. J Physiol Sci 2020; 70:33. [PMID: 32646367 PMCID: PMC10717230 DOI: 10.1186/s12576-020-00761-2] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2019] [Accepted: 07/03/2020] [Indexed: 12/23/2022]
Abstract
Maternal-fetal calcium (Ca2+) transport in the placenta plays a critical role in maintaining fetal bone mineralization. Mutations in the gene encoding the transient receptor potential cation channel, subfamily V, member 6 (TRPV6) have been identified as causative mutations of transient neonatal hyperparathyroidism due to insufficient maternal-fetal Ca2+ transport in the placenta. In this study, we found two novel mutations in subjects that have transient neonatal hyperparathyroidism. TRPV6 carrying the mutation p.Arg390His that localizes to the outer edge of the first transmembrane domain (S1) showed impaired trafficking to the plasma membrane, whereas TRPV6 having the mutation p.Gly291Ser in the sixth ankyrin repeat (AR) domain had channel properties that were comparable those of WT channels, although the increases in steady-state intracellular Ca2+ concentration could have led to Ca2+ overload and subsequent death of cells expressing this mutant channel. These results indicate that the AR6 domain contributes to TRPV6-mediated maintenance of intracellular Ca2+ concentrations, and that this region could play a novel role in regulating the activity of TRPV6 Ca2+-selective channels.
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Affiliation(s)
- Yoshiro Suzuki
- Department of Physiology, Iwate Medical University, 1-1-1 Idaidori, Yahaba-cho, Shiwa-gun, Iwate, 028-3694, Japan.
- Division of Cell Signaling, National Institute for Physiological Sciences (Exploratory Research Center on Life and Living Systems), National Institutes of Natural Sciences, Okazaki, 444-8787, Japan.
- Department of Physiological Sciences, SOKENDAI (The Graduate University for Advanced Studies), Okazaki, 444-8787, Japan.
| | - Hirotake Sawada
- Department of Fundamental Nursing, Faculty of Medicine, University of Miyazaki, Miyazaki, 889-1692, Japan
| | - Tomoko Tokumasu
- Department of Pediatrics, Kurashiki Central Hospital, Kurashiki, 710-8602, Japan
| | - Shigeru Suzuki
- Department of Pediatrics, Asahikawa-Kosei General Hospital, Asahikawa, 078-8211, Japan
- Department of Pediatrics, Asahikawa Medical University, Asahikawa, 078-8510, Japan
| | - Shinsuke Ninomiya
- Department of Clinical Genetics, Kurashiki Central Hospital, Kurashiki, 710-8602, Japan
| | - Masaru Shirai
- Department of Pediatrics, Asahikawa-Kosei General Hospital, Asahikawa, 078-8211, Japan
| | - Tokuo Mukai
- Department of Pediatrics, Asahikawa-Kosei General Hospital, Asahikawa, 078-8211, Japan
- Department of Pediatrics, Japanese Red Cross Asahikawa Hospital, Asahikawa, 070-8530, Japan
| | - Claire T Saito
- Division of Cell Signaling, National Institute for Physiological Sciences (Exploratory Research Center on Life and Living Systems), National Institutes of Natural Sciences, Okazaki, 444-8787, Japan
| | - Gen Nishimura
- Center for Intractable Disease, Saitama Medical University Hospital, Saitama, 350-0495, Japan
| | - Makoto Tominaga
- Division of Cell Signaling, National Institute for Physiological Sciences (Exploratory Research Center on Life and Living Systems), National Institutes of Natural Sciences, Okazaki, 444-8787, Japan
- Department of Physiological Sciences, SOKENDAI (The Graduate University for Advanced Studies), Okazaki, 444-8787, Japan
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36
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Zou W, Wang Y, Ren X, Wang L, Deng S, Mao X, Li Z, Liao Z. TRPV6
variants confer susceptibility to chronic pancreatitis in the Chinese population. Hum Mutat 2020; 41:1351-1357. [DOI: 10.1002/humu.24032] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2020] [Revised: 04/28/2020] [Accepted: 05/04/2020] [Indexed: 02/06/2023]
Affiliation(s)
- Wen‐Bin Zou
- Department of Gastroenterology, Digestive Endoscopy Center, Changhai HospitalSecond Military Medical University Shanghai China
- Shanghai Institute of Pancreatic Diseases Shanghai China
| | - Yuan‐Chen Wang
- Department of Gastroenterology, Digestive Endoscopy Center, Changhai HospitalSecond Military Medical University Shanghai China
- Shanghai Institute of Pancreatic Diseases Shanghai China
| | - Xin‐Lu Ren
- Department of Clinical MedicineQueen Mary College of Nanchang University Nanchang China
| | - Lei Wang
- Shi‐Shi BioPharmWuhan Institute of Biotechnology Wuhan China
| | - Shun‐Jiang Deng
- Department of Gastroenterology, Digestive Endoscopy Center, Changhai HospitalSecond Military Medical University Shanghai China
- Shanghai Institute of Pancreatic Diseases Shanghai China
| | - Xiao‐Tong Mao
- Department of Gastroenterology, Digestive Endoscopy Center, Changhai HospitalSecond Military Medical University Shanghai China
- Shanghai Institute of Pancreatic Diseases Shanghai China
| | - Zhao‐Shen Li
- Department of Gastroenterology, Digestive Endoscopy Center, Changhai HospitalSecond Military Medical University Shanghai China
- Shanghai Institute of Pancreatic Diseases Shanghai China
| | - Zhuan Liao
- Department of Gastroenterology, Digestive Endoscopy Center, Changhai HospitalSecond Military Medical University Shanghai China
- Shanghai Institute of Pancreatic Diseases Shanghai China
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37
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Masamune A, Kotani H, Sörgel FL, Chen JM, Hamada S, Sakaguchi R, Masson E, Nakano E, Kakuta Y, Niihori T, Funayama R, Shirota M, Hirano T, Kawamoto T, Hosokoshi A, Kume K, Unger L, Ewers M, Laumen H, Bugert P, Mori MX, Tsvilovskyy V, Weißgerber P, Kriebs U, Fecher-Trost C, Freichel M, Diakopoulos KN, Berninger A, Lesina M, Ishii K, Itoi T, Ikeura T, Okazaki K, Kaune T, Rosendahl J, Nagasaki M, Uezono Y, Algül H, Nakayama K, Matsubara Y, Aoki Y, Férec C, Mori Y, Witt H, Shimosegawa T. Variants That Affect Function of Calcium Channel TRPV6 Are Associated With Early-Onset Chronic Pancreatitis. Gastroenterology 2020; 158:1626-1641.e8. [PMID: 31930989 DOI: 10.1053/j.gastro.2020.01.005] [Citation(s) in RCA: 71] [Impact Index Per Article: 17.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/15/2019] [Revised: 12/09/2019] [Accepted: 01/02/2020] [Indexed: 01/21/2023]
Abstract
BACKGROUND & AIMS Changes in pancreatic calcium levels affect secretion and might be involved in development of chronic pancreatitis (CP). We investigated the association of CP with the transient receptor potential cation channel subfamily V member 6 gene (TRPV6), which encodes a Ca2+-selective ion channel, in an international cohort of patients and in mice. METHODS We performed whole-exome DNA sequencing from a patient with idiopathic CP and from his parents, who did not have CP. We validated our findings by sequencing DNA from 300 patients with CP (not associated with alcohol consumption) and 1070 persons from the general population in Japan (control individuals). In replication studies, we sequenced DNA from patients with early-onset CP (20 years or younger) not associated with alcohol consumption from France (n = 470) and Germany (n = 410). We expressed TRPV6 variants in HEK293 cells and measured their activity using Ca2+ imaging assays. CP was induced by repeated injections of cerulein in TRPV6mut/mut mice. RESULTS We identified the variants c.629C>T (p.A210V) and c.970G>A (p.D324N) in TRPV6 in the index patient. Variants that affected function of the TRPV6 product were found in 13 of 300 patients (4.3%) and 1 of 1070 control individuals (0.1%) from Japan (odds ratio [OR], 48.4; 95% confidence interval [CI], 6.3-371.7; P = 2.4 × 10-8). Twelve of 124 patients (9.7%) with early-onset CP had such variants. In the replication set from Europe, 18 patients with CP (2.0%) carried variants that affected the function of the TRPV6 product compared with 0 control individuals (P = 6.2 × 10-8). Variants that did not affect the function of the TRPV6 product (p.I223T and p.D324N) were overrepresented in Japanese patients vs control individuals (OR, 10.9; 95% CI, 4.5-25.9; P = 7.4 × 10-9 for p.I223T and P = .01 for p.D324N), whereas the p.L299Q was overrepresented in European patients vs control individuals (OR, 3.0; 95% CI, 1.9-4.8; P = 1.2 × 10-5). TRPV6mut/mut mice given cerulein developed more severe pancreatitis than control mice, as shown by increased levels of pancreatic enzymes, histologic alterations, and pancreatic fibrosis. CONCLUSIONS We found that patients with early-onset CP not associated with alcohol consumption carry variants in TRPV6 that affect the function of its product, perhaps by altering Ca2+ balance in pancreatic cells. TRPV6 regulates Ca2+ homeostasis and pancreatic inflammation.
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Affiliation(s)
- Atsushi Masamune
- Division of Gastroenterology, Tohoku University Graduate School of Medicine, Sendai, Japan.
| | - Hiroshi Kotani
- Laboratory of Molecular Biology, Department of Synthetic Chemistry and Biological Chemistry, Graduate School of Engineering, Kyoto University, Kyoto, Japan
| | - Franziska Lena Sörgel
- Else Kröner-Fresenius-Zentrum für Ernährungsmedizin, Paediatric Nutritional Medicine, Technische Universität München, Freising, Germany
| | - Jian-Min Chen
- Inserm, Univ Brest, EFS, UMR 1078, GGB, Brest, France
| | - Shin Hamada
- Division of Gastroenterology, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Reiko Sakaguchi
- Laboratory of Molecular Biology, Department of Synthetic Chemistry and Biological Chemistry, Graduate School of Engineering, Kyoto University, Kyoto, Japan; Institute for Integrated Cell-Material Sciences, Kyoto University, Kyoto, Japan
| | - Emmanuelle Masson
- Inserm, Univ Brest, EFS, UMR 1078, GGB, Brest, France; CHU Brest, Service de Génétique, Brest, France
| | - Eriko Nakano
- Division of Gastroenterology, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Yoichi Kakuta
- Division of Gastroenterology, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Tetsuya Niihori
- Department of Medical Genetics, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Ryo Funayama
- Division of Cell Proliferation, United Centers for Advanced Research and Translational Medicine, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Matsuyuki Shirota
- Division of Cell Proliferation, United Centers for Advanced Research and Translational Medicine, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Tatsuya Hirano
- Laboratory of Molecular Biology, Department of Synthetic Chemistry and Biological Chemistry, Graduate School of Engineering, Kyoto University, Kyoto, Japan
| | - Tetsuya Kawamoto
- Laboratory of Molecular Biology, Department of Synthetic Chemistry and Biological Chemistry, Graduate School of Engineering, Kyoto University, Kyoto, Japan
| | - Atsuki Hosokoshi
- Laboratory of Molecular Biology, Department of Synthetic Chemistry and Biological Chemistry, Graduate School of Engineering, Kyoto University, Kyoto, Japan
| | - Kiyoshi Kume
- Division of Gastroenterology, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Lara Unger
- Else Kröner-Fresenius-Zentrum für Ernährungsmedizin, Paediatric Nutritional Medicine, Technische Universität München, Freising, Germany
| | - Maren Ewers
- Else Kröner-Fresenius-Zentrum für Ernährungsmedizin, Paediatric Nutritional Medicine, Technische Universität München, Freising, Germany
| | - Helmut Laumen
- Else Kröner-Fresenius-Zentrum für Ernährungsmedizin, Paediatric Nutritional Medicine, Technische Universität München, Freising, Germany
| | - Peter Bugert
- Institute of Transfusion Medicine and Immunology, Medical Faculty Mannheim, Heidelberg University, German Red Cross Blood Service of Baden-Württemberg-Hessen, Mannheim, Germany
| | - Masayuki X Mori
- Laboratory of Molecular Biology, Department of Synthetic Chemistry and Biological Chemistry, Graduate School of Engineering, Kyoto University, Kyoto, Japan
| | - Volodymyr Tsvilovskyy
- Pharmakologisches Institut, Universität Heidelberg, Heidelberg, Germany; German Center for Cardiovascular Research, partner site Heidelberg, Germany
| | - Petra Weißgerber
- Experimentelle und Klinische Pharmakologie und Toxikologie, Universität des Saarlandes, Homburg, Germany
| | - Ulrich Kriebs
- Pharmakologisches Institut, Universität Heidelberg, Heidelberg, Germany; German Center for Cardiovascular Research, partner site Heidelberg, Germany
| | - Claudia Fecher-Trost
- Experimentelle und Klinische Pharmakologie und Toxikologie, Universität des Saarlandes, Homburg, Germany
| | - Marc Freichel
- Pharmakologisches Institut, Universität Heidelberg, Heidelberg, Germany; German Center for Cardiovascular Research, partner site Heidelberg, Germany
| | - Kalliope N Diakopoulos
- Mildred Scheel Chair of Tumor Metabolism and Comprehensive Cancer Center Munich at the Klinikum rechts der Isar, Technical University of Munich, Munich, Germany
| | - Alexandra Berninger
- Mildred Scheel Chair of Tumor Metabolism and Comprehensive Cancer Center Munich at the Klinikum rechts der Isar, Technical University of Munich, Munich, Germany
| | - Marina Lesina
- Mildred Scheel Chair of Tumor Metabolism and Comprehensive Cancer Center Munich at the Klinikum rechts der Isar, Technical University of Munich, Munich, Germany
| | - Kentaro Ishii
- Department of Gastroenterology and Hepatology, Tokyo Medical University, Tokyo, Japan
| | - Takao Itoi
- Department of Gastroenterology and Hepatology, Tokyo Medical University, Tokyo, Japan
| | - Tsukasa Ikeura
- Department of Gastroenterology and Hepatology, Kansai Medical University, Hirakata, Japan
| | - Kazuichi Okazaki
- Department of Gastroenterology and Hepatology, Kansai Medical University, Hirakata, Japan
| | - Tom Kaune
- Department of Internal Medicine I, Martin Luther University, Halle (Saale), Germany
| | - Jonas Rosendahl
- Department of Internal Medicine I, Martin Luther University, Halle (Saale), Germany
| | - Masao Nagasaki
- Department of Integrative Genomics, Tohoku Medical Megabank Organization, Tohoku University, Sendai, Japan
| | - Yasuhito Uezono
- Cancer Pathophysiology Division, National Cancer Center Research Institute, Tokyo, Japan
| | - Hana Algül
- Mildred Scheel Chair of Tumor Metabolism and Comprehensive Cancer Center Munich at the Klinikum rechts der Isar, Technical University of Munich, Munich, Germany
| | - Keiko Nakayama
- Division of Cell Proliferation, United Centers for Advanced Research and Translational Medicine, Tohoku University Graduate School of Medicine, Sendai, Japan
| | | | - Yoko Aoki
- Department of Medical Genetics, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Claude Férec
- Inserm, Univ Brest, EFS, UMR 1078, GGB, Brest, France; CHU Brest, Service de Génétique, Brest, France
| | - Yasuo Mori
- Laboratory of Molecular Biology, Department of Synthetic Chemistry and Biological Chemistry, Graduate School of Engineering, Kyoto University, Kyoto, Japan
| | - Heiko Witt
- Else Kröner-Fresenius-Zentrum für Ernährungsmedizin, Paediatric Nutritional Medicine, Technische Universität München, Freising, Germany
| | - Tooru Shimosegawa
- Division of Gastroenterology, Tohoku University Graduate School of Medicine, Sendai, Japan
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Sahin-Tóth M. Channelopathy of the Pancreas Causes Chronic Pancreatitis. Gastroenterology 2020; 158:1538-1540. [PMID: 32205170 PMCID: PMC7751598 DOI: 10.1053/j.gastro.2020.03.027] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/28/2020] [Accepted: 03/06/2020] [Indexed: 12/02/2022]
Affiliation(s)
- Miklós Sahin-Tóth
- Department of Surgery, University of California Los Angeles, Los Angeles, California.
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van Goor MK, de Jager L, Cheng Y, van der Wijst J. High-resolution structures of transient receptor potential vanilloid channels: Unveiling a functionally diverse group of ion channels. Protein Sci 2020; 29:1569-1580. [PMID: 32232875 PMCID: PMC7314393 DOI: 10.1002/pro.3861] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2020] [Revised: 03/21/2020] [Accepted: 03/24/2020] [Indexed: 12/13/2022]
Abstract
Transient receptor potential vanilloid (TRPV) channels are part of the superfamily of TRP ion channels and play important roles in widespread physiological processes including both neuronal and non‐neuronal pathways. Various diseases such as skeletal abnormalities, chronic pain, and cancer are associated with dysfunction of a TRPV channel. In order to obtain full understanding of disease pathogenesis and create opportunities for therapeutic intervention, it is essential to unravel how these channels function at a molecular level. In the past decade, incredible progress has been made in biochemical sample preparation of large membrane proteins and structural biology techniques, including cryo‐electron microscopy. This has resulted in high resolution structures of all TRPV channels, which has provided novel insights into the molecular mechanisms of channel gating and regulation that will be summarized in this review.
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Affiliation(s)
- Mark K van Goor
- Department of Physiology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Leanne de Jager
- Department of Physiology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Yifan Cheng
- Department of Biochemistry and Biophysics, University of California San Francisco, San Francisco, California, United States.,Howard Hughes Medical Institute, University of California, San Francisco, California, United States
| | - Jenny van der Wijst
- Department of Physiology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, The Netherlands
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Marx SJ, Sinaii N. Neonatal Severe Hyperparathyroidism: Novel Insights From Calcium, PTH, and the CASR Gene. J Clin Endocrinol Metab 2020; 105:5645387. [PMID: 31778168 PMCID: PMC7111126 DOI: 10.1210/clinem/dgz233] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/25/2019] [Accepted: 11/26/2019] [Indexed: 12/24/2022]
Abstract
CONTEXT Neonatal severe hyperparathyroidism (NSHPT) is rare and potentially lethal. It is usually from homozygous or heterozygous germline-inactivating CASR variant(s). NSHPT shows a puzzling range of serum calcium and parathyroid hormone (PTH) levels. Optimal therapy is unclear. EVIDENCE ACQUISITION We categorized genotype/phenotype pairings related to CASRs. For the 2 pairings in NSHPT, each of 57 cases of neonatal severe hyperparathyroidism required calcium, PTH, upper normal PTH, and dosage of a germline pathogenic CASR variant. EVIDENCE SYNTHESIS Homozygous and heterozygous NSHPT are 2 among a spectrum of 9 genotype/phenotype pairings relating to CASRs and NSHPT. For the 2 NSHPT pairings, expressions differ in CASR allelic dosage, CASR variant severity, and sufficiency of maternofetal calcium fluxes. Homozygous dosage of CASR variants was generally more aggressive than heterozygous. Among heterozygotes, high-grade CASR variants in vitro were more pathogenic in vivo than low-grade variants. Fetal calcium insufficiency as from maternal hypoparathyroidism caused fetal secondary hyperparathyroidism, which persisted and was reversible in neonates. Among NSHPT pairings, calcium and PTH were higher in CASR homozygotes than in heterozygotes. Extreme hypercalcemia (above 4.5 mM; normal 2.2-2.6 mM) is a robust biomarker, occurring only in homozygotes (83% of that pairing). It could occur during the first week. CONCLUSIONS In NSHPT pairings, the homozygotes for pathogenic CASR variants show higher calcium and PTH levels than heterozygotes. Calcium levels above 4.5 mM among NSHPT are frequent and unique only to most homozygotes. This cutoff supports early and robust diagnosis of CASR dosage. Thereby, it promotes definitive total parathyroidectomy in most homozygotes.
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MESH Headings
- Biomarkers/analysis
- Calcium/blood
- Female
- Genotype
- Heterozygote
- Homozygote
- Humans
- Hyperparathyroidism, Primary/blood
- Hyperparathyroidism, Primary/diagnosis
- Hyperparathyroidism, Primary/genetics
- Infant, Newborn
- Infant, Newborn, Diseases/blood
- Infant, Newborn, Diseases/diagnosis
- Infant, Newborn, Diseases/genetics
- Male
- Mutation
- Parathyroid Hormone/blood
- Prognosis
- Receptors, Calcium-Sensing/genetics
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Affiliation(s)
- Stephen J Marx
- Office of the Scientific Director, Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD), Bethesda, MD
- Correspondence: Stephen Marx MD, N.I.H., Bld 6A, Room 2A-04A, MSC 0614, 6 Center Drive, Bethesda, MD 20892, USA. E-mail:
| | - Ninet Sinaii
- Biostatistics and Clinical Epidemiology Service, National Institutes of Health Clinical Center, Bethesda, MD
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Mason AE, Grier D, Smithson SF, Burren CP, Gradhand E. Post-mortem histology in transient receptor potential cation channel subfamily V member 6 (TRPV6) under-mineralising skeletal dysplasia suggests postnatal skeletal recovery: a case report. BMC MEDICAL GENETICS 2020; 21:64. [PMID: 32228492 PMCID: PMC7106792 DOI: 10.1186/s12881-020-01007-z] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/21/2019] [Accepted: 03/20/2020] [Indexed: 12/14/2022]
Abstract
Background The calcium-selective channel TRPV6 (transient receptor potential cation channel subfamily V member 6) is crucial for maternal-fetal calcium transport across the placenta. TRPV6 mutations have recently been associated with an antenatally severe under-mineralising skeletal dysplasia accompanied by postnatal biochemical abnormalities. This is the first post-mortem report in a patient with TRPV6 skeletal dysplasia. Case presentation The female infant had severe antenatal and postnatal skeletal abnormalities by 20 weeks gestation and was ventilator-dependent from birth. These skeletal abnormalities were apparent at an earlier gestational age than in previous reported cases and a more severe clinical course ensued. Biochemical and skeletal abnormalities, including bone density, improved postnatally but cardiac arrest at 4 months of age led to withdrawal of intensive care. Compound heterozygous TRPV6 variants (c.1978G > C p.(Gly660Arg) and c.1528C > T p.(Arg510Ter)) were identified on exome sequencing. Post-mortem identified skeletal abnormalities but no specific abnormalities in other organ systems. No placental pathology was found, multi-organ histological features reflected prolonged intensive care only. Post-mortem macroscopic examination indicated reduced thoracic size and short, pale and pliable ribs. Histological examination identified reduced number of trabeculae in the diaphyses (away from the growth plates), whereas metaphyses showed adequate mineralisation and normal number of trabeculae, but with slightly enlarged reactive chondrocytes, indicating post-natal skeletal growth recovery. Post-mortem radiological findings demonstrated improved bone density, improved rib width, healed fractures, although ribs were still shorter than normal. Long bones (especially humerus and femur) had improved from initial poorly defined metaphyses and reduced bone density to sharply defined metaphyses, prominent growth restart lines in distal diaphyses and bone-in-bone appearance along diaphyses. Conclusions This case provide bone histological confirmation that human skeletal development is compromised in the presence of TRPV6 pathogenic variants. Post-mortem findings were consistent with abnormal in utero skeletal mineralisation due to severe calcium deficit from compromised placental calcium transfer, followed by subsequent phenotypic improvement with adequate postnatal calcium availability. Significant skeletal recovery occurs in the early weeks of postnatal life in TRPV6 skeletal dysplasia.
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Affiliation(s)
- Anna E Mason
- Bristol Medical School Translational Health Sciences, University of Bristol, Bristol, UK
| | - David Grier
- Department of Radiology, Bristol Royal Hospital for Children, University Hospitals Bristol NHS Foundation Trust, Bristol, UK
| | - Sarah F Smithson
- Bristol Medical School Translational Health Sciences, University of Bristol, Bristol, UK.,Department of Clinical Genetics, St Michaels Hospital, University Hospitals Bristol NHS Foundation Trust, Bristol, UK
| | - Christine P Burren
- Bristol Medical School Translational Health Sciences, University of Bristol, Bristol, UK.,Department of Paediatric Endocrinology, Bristol Royal Hospital for Children, University Hospitals Bristol NHS Foundation Trust, Bristol, UK
| | - Elise Gradhand
- Severn Pathology, Paediatric and Perinatal Pathology, Southmead Hospital, North Bristol NHS Trust, Bristol, UK. .,Dr. Senckenberg. Institut für Pathologie, Universitätsklinikum Frankfurt/Main, Theodor-Stern-Kai 7, 60590, Frankfurt, Germany.
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Yelshanskaya MV, Nadezhdin KD, Kurnikova MG, Sobolevsky AI. Structure and function of the calcium-selective TRP channel TRPV6. J Physiol 2020; 599:2673-2697. [PMID: 32073143 DOI: 10.1113/jp279024] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2019] [Accepted: 02/03/2020] [Indexed: 12/23/2022] Open
Abstract
Epithelial calcium channel TRPV6 is a member of the vanilloid subfamily of TRP channels that is permeable to cations and highly selective to Ca2+ ; it shows constitutive activity regulated negatively by Ca2+ and positively by phosphoinositol and cholesterol lipids. In this review, we describe the molecular structure of TRPV6 and discuss how its structural elements define its unique functional properties. High Ca2+ selectivity of TRPV6 originates from the narrow selectivity filter, where Ca2+ ions are directly coordinated by a ring of anionic aspartate side chains. Divalent cations Ca2+ and Ba2+ permeate TRPV6 pore according to the knock-off mechanism, while tight binding of Gd3+ to the aspartate ring blocks the channel and prevents Na+ from permeating the pore. The iris-like channel opening is accompanied by an α-to-π helical transition in the pore-lining transmembrane helix S6. As a result of this transition, the intracellular halves of the S6 helices bend and rotate by about 100 deg, exposing different residues to the channel pore in the open and closed states. Channel opening is also associated with changes in occupancy of the transmembrane domain lipid binding sites. The inhibitor 2-aminoethoxydiphenyl borate (2-APB) binds to TRPV6 in a pocket formed by the cytoplasmic half of the S1-S4 transmembrane helical bundle and shifts open-closed channel equilibrium towards the closed state by outcompeting lipids critical for activation. Ca2+ inhibits TRPV6 via binding to calmodulin (CaM), which mediates Ca2+ -dependent inactivation. The TRPV6-CaM complex exhibits 1:1 stoichiometry; one TRPV6 tetramer binds both CaM lobes, which adopt a distinct head-to-tail arrangement. The CaM C-terminal lobe plugs the channel through a unique cation-π interaction by inserting the side chain of lysine K115 into a tetra-tryptophan cage at the ion channel pore intracellular entrance. Recent studies of TRPV6 structure and function described in this review advance our understanding of the role of this channel in physiology and pathophysiology and inform new therapeutic design.
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Affiliation(s)
- Maria V Yelshanskaya
- Department of Biochemistry and Molecular Biophysics, Columbia University, 650 West 168th Street, New York, NY, 10032, USA
| | - Kirill D Nadezhdin
- Department of Biochemistry and Molecular Biophysics, Columbia University, 650 West 168th Street, New York, NY, 10032, USA
| | - Maria G Kurnikova
- Chemistry Department, Carnegie Mellon University, 4400 Fifth Ave, Pittsburgh, PA, 15213, USA
| | - Alexander I Sobolevsky
- Department of Biochemistry and Molecular Biophysics, Columbia University, 650 West 168th Street, New York, NY, 10032, USA
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Abstract
Two decades ago a class of ion channels, hitherto unsuspected, was discovered. In mammals these Transient Receptor Potential channels (TRPs) have not only expanded in number (to 26 functional channels) but also expanded the view of our interface with the physical and chemical environment. Some are heat and cold sensors while others monitor endogenous and/or exogenous chemical signals. Some TRP channels monitor osmotic potential, and others measure cell movement, stretching, and fluid flow. Many TRP channels are major players in nociception and integration of pain signals. One member of the vanilloid sub-family of channels is TRPV6. This channel is highly selective for divalent cations, particularly calcium, and plays a part in general whole-body calcium homeostasis, capturing calcium in the gut from the diet. TRPV6 can be greatly elevated in a number of cancers deriving from epithelia and considerable study has been made of its role in the cancer phenotype where calcium control is dysfunctional. This review compiles and updates recent published work on TRPV6 as a promising drug target in a number of cancers including those afflicting breast, ovarian, prostate and pancreatic tissues.
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Affiliation(s)
- John M Stewart
- Soricimed Biopharma Inc. 18 Botsford Street, Moncton, NB, Canada, E1C 4W7
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Screening of Molecular Targets of Action of Atractylodin in Cholangiocarcinoma by Applying Proteomic and Metabolomic Approaches. Metabolites 2019; 9:metabo9110260. [PMID: 31683902 PMCID: PMC6918361 DOI: 10.3390/metabo9110260] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2019] [Revised: 10/29/2019] [Accepted: 10/31/2019] [Indexed: 12/21/2022] Open
Abstract
Cholangiocarcinoma (CCA) is cancer of the bile duct and the highest incidence of CCA in the world is reported in Thailand. Our previous in vitro and in vivo studies identified Atractylodes lancea (Thunb) D.C. as a promising candidate for CCA treatment. The present study aimed to examine the molecular targets of action of atractylodin, the bioactive compound isolated from A. lancea, in CCA cell line by applying proteomic and metabolomic approaches. Intra- and extracellular proteins and metabolites were identified by LC-MS/MS following exposure of CL-6, the CCA cell line, to atractylodin for 24 and 48 h. Analysis of the protein functions and pathways involved was performed using a Venn diagram, PANTHER, and STITCH software. Analysis of the metabolite functions and pathways involved, including the correlation between proteins and metabolites identified was performed using MetaboAnalyst software. Results suggested the involvement of atractylodin in various cell biology processes. These include the cell cycle, apoptosis, DNA repair, immune response regulation, wound healing, blood vessel development, pyrimidine metabolism, the citrate cycle, purine metabolism, arginine and proline metabolism, glyoxylate and dicarboxylate metabolism, the pentose phosphate pathway, and fatty acid biosynthesis. Therefore, it was proposed that the action of atractylodin may involve the destruction of the DNA of cancer cells, leading to cell cycle arrest and cell apoptosis.
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Beggs MR, Lee JJ, Busch K, Raza A, Dimke H, Weissgerber P, Engel J, Flockerzi V, Alexander RT. TRPV6 and Ca v1.3 Mediate Distal Small Intestine Calcium Absorption Before Weaning. Cell Mol Gastroenterol Hepatol 2019; 8:625-642. [PMID: 31398491 PMCID: PMC6889763 DOI: 10.1016/j.jcmgh.2019.07.005] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/02/2019] [Revised: 07/15/2019] [Accepted: 07/17/2019] [Indexed: 12/12/2022]
Abstract
BACKGROUND & AIMS Intestinal Ca2+ absorption early in life is vital to achieving optimal bone mineralization. The molecular details of intestinal Ca2+ absorption have been defined in adults after peak bone mass is obtained, but they are largely unexplored during development. We sought to delineate the molecular details of transcellular Ca2+ absorption during this critical period. METHODS Expression of small intestinal and renal calcium transport genes was assessed by using quantitative polymerase chain reaction. Net calcium flux across small intestinal segments was measured in Ussing chambers, including after pharmacologic inhibition or genetic manipulation of TRPV6 or Cav1.3 calcium channels. Femurs were analyzed by using micro-computed tomography and histology. RESULTS Net TRPV6-mediated Ca2+ flux across the duodenum was absent in pre-weaned (P14) mice but present after weaning. In contrast, we found significant transcellular Ca2+ absorption in the jejunum at 2 weeks but not 2 months of age. Net jejunal Ca2+ absorption observed at P14 was not present in either Trpv6 mutant (D541A) mice or Cav1.3 knockout mice. We observed significant nifedipine-sensitive transcellular absorption across the ileum at P14 but not 2 months. Cav1.3 knockout pups exhibited delayed bone mineral accrual, compensatory nifedipine-insensitive Ca2+ absorption in the ileum, and increased expression of renal Ca2+ reabsorption mediators at P14. Moreover, weaning pups at 2 weeks reduced jejunal and ileal Cav1.3 expression. CONCLUSIONS We have detailed novel pathways contributing to transcellular Ca2+ transport across the distal small intestine of mice during development, highlighting the complexity of the multiple mechanisms involved in achieving a positive Ca2+ balance early in life.
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Affiliation(s)
- Megan R. Beggs
- Department of Physiology, University of Alberta, Edmonton, Alberta, Canada,The Women’s & Children’s Health Research Institute, Edmonton, Alberta, Canada
| | - Justin J. Lee
- Department of Physiology, University of Alberta, Edmonton, Alberta, Canada,The Women’s & Children’s Health Research Institute, Edmonton, Alberta, Canada
| | - Kai Busch
- Experimentelle und Klinische Pharmakologie und Toxikologie, Saarland University, Homburg, Germany
| | - Ahsan Raza
- Experimentelle und Klinische Pharmakologie und Toxikologie, Saarland University, Homburg, Germany
| | - Henrik Dimke
- Department of Cardiovascular and Renal Research, Institute of Molecular Medicine, University of Southern Denmark, Odense, Denmark
| | - Petra Weissgerber
- Experimentelle und Klinische Pharmakologie und Toxikologie, Saarland University, Homburg, Germany
| | - Jutta Engel
- Department of Biophysics, Center for Integrative Physiology and Molecular Medicine (CIPMM), Saarland University, School of Medicine, Homburg, Germany
| | - Veit Flockerzi
- Experimentelle und Klinische Pharmakologie und Toxikologie, Saarland University, Homburg, Germany
| | - R. Todd Alexander
- Department of Physiology, University of Alberta, Edmonton, Alberta, Canada,The Women’s & Children’s Health Research Institute, Edmonton, Alberta, Canada,Department of Pediatrics, University of Alberta, Edmonton, Alberta, Canada,Correspondence Address correspondence to: R. Todd Alexander, MD, PhD, Department of Pediatrics, 4-585 Edmonton Clinic Health Academy, 11405 – 87 Avenue, University of Alberta, Edmonton, Alberta T6G 2R7, Canada. fax: (780) 248-5556.
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Fecher-Trost C, Lux F, Busch KM, Raza A, Winter M, Hielscher F, Belkacemi T, van der Eerden B, Boehm U, Freichel M, Weissgerber P. Maternal Transient Receptor Potential Vanilloid 6 (Trpv6) Is Involved In Offspring Bone Development. J Bone Miner Res 2019; 34:699-710. [PMID: 30786075 DOI: 10.1002/jbmr.3646] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/17/2018] [Revised: 11/16/2018] [Accepted: 11/18/2018] [Indexed: 12/29/2022]
Abstract
Embryonic growth and bone development depend on placental Ca2+ transport across the feto-maternal barrier to supply minerals to the fetus. The individual factors and cellular mechanisms that regulate placental Ca2+ transfer, however, are only beginning to emerge. We find that the Ca2+ -selective transient receptor potential vanilloid 6 (TRPV6) channel is expressed in trophoblasts of the fetal labyrinth, in the yolk sac, and in the maternal part of the placenta. Lack of functional TRPV6 channels in the mother leads to a reduced Ca2+ content in both placenta and embryo. Ca2+ uptake in trophoblasts is impaired in the absence of Trpv6. Trpv6-deficient embryos are smaller, have a lower body weight, and shorter and less calcified femurs. The altered cortical bone microarchitecture persists in adulthood. We show that TRPV6's Ca2+ -conducting property causes this embryonic and bone phenotype. Our results show that TRPV6 is necessary for the Ca2+ uptake in trophoblasts and that TRPV6 deficiency in the placenta leads to reduced embryo growth, minor bone calcification, and impaired bone development. © 2019 American Society for Bone and Mineral Research.
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Affiliation(s)
- Claudia Fecher-Trost
- Pharmacology and Toxicology, Center for Molecular Signaling (PZMS), Saarland University School of Medicine, Homburg, Germany
| | - Femke Lux
- Pharmacology and Toxicology, Center for Molecular Signaling (PZMS), Saarland University School of Medicine, Homburg, Germany
| | - Kai-Markus Busch
- Pharmacology and Toxicology, Center for Molecular Signaling (PZMS), Saarland University School of Medicine, Homburg, Germany
| | - Ahsan Raza
- Pharmacology and Toxicology, Center for Molecular Signaling (PZMS), Saarland University School of Medicine, Homburg, Germany
| | - Manuel Winter
- Pharmacology and Toxicology, Center for Molecular Signaling (PZMS), Saarland University School of Medicine, Homburg, Germany
| | - Franziska Hielscher
- Pharmacology and Toxicology, Center for Molecular Signaling (PZMS), Saarland University School of Medicine, Homburg, Germany
| | - Thabet Belkacemi
- Pharmacology and Toxicology, Center for Molecular Signaling (PZMS), Saarland University School of Medicine, Homburg, Germany
| | - Bram van der Eerden
- Department of Internal Medicine, Laboratory for Calcium and Bone Metabolism, Erasmus MC, Rotterdam, Netherlands
| | - Ulrich Boehm
- Pharmacology and Toxicology, Center for Molecular Signaling (PZMS), Saarland University School of Medicine, Homburg, Germany
| | - Marc Freichel
- Institute of Pharmacology, Heidelberg University, Heidelberg, Germany
| | - Petra Weissgerber
- Pharmacology and Toxicology, Center for Molecular Signaling (PZMS), Saarland University School of Medicine, Homburg, Germany.,Transgenic Technologies, Center for Molecular Signaling (PZMS), Saarland University School of Medicine, Homburg, Germany
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Yamashita S, Mizumoto H, Sawada H, Suzuki Y, Hata D. TRPV6 Gene Mutation in a Dizygous Twin With Transient Neonatal Hyperparathyroidism. J Endocr Soc 2019; 3:602-606. [PMID: 30820485 PMCID: PMC6389352 DOI: 10.1210/js.2018-00374] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/14/2018] [Accepted: 12/28/2018] [Indexed: 01/27/2023] Open
Abstract
Maternal-fetal transport of calcium (Ca2+) is important for bone mineralization in fetal development. Insufficient Ca2+ transport causes transient neonatal hyperparathyroidism (TNHP). Transient receptor potential cation channel, subfamily V, member 6 (TRPV6), has been found to play an important role in the active transport of Ca2+ through the placenta. Recently, TRPV6 gene was found to be the gene responsible for TNHP with severe skeletal undermineralization. To date, only seven cases of TNHP caused by TRPV6 recessive mutations have been reported. We present a case of TNHP caused by TRPV6 gene mutations. A female newborn was hospitalized because of respiratory distress. Marked undermineralization of the skeleton was observed in X-ray imaging. Laboratory examination revealed markedly high PTH and absence of hypercalcemia along with vitamin D deficiency. Her twin brother presented with almost no symptoms. Maternal laboratory findings indicated normocalcemia, but vitamin D deficiency with a high PTH level for the lactation period was observed. We initially diagnosed the patient as having secondary hyperparathyroidism because of maternal vitamin D deficiency. Nevertheless, the reasons underlying the discordant clinical manifestations between the twin siblings remained unclear. Our analysis of TRPV6 gene clarified that the patient had compound heterozygote mutations, which were reported previously (p.Ile223Thr and p.Gly428Arg). Pathologic mutations in TRPV6 gene were not detected in the other sibling. The clinical symptoms in the patient were transient: they resolved during infancy. TNHP caused by TRPV6 gene mutations is a unique disease in terms of its transient pathology in utero and relief after birth.
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Affiliation(s)
- Sumie Yamashita
- Department of Pediatrics, Kitano Hospital, Tazuke Kofukai Medical Research Institute, Osaka, Japan
| | - Hiroshi Mizumoto
- Department of Pediatrics, Kitano Hospital, Tazuke Kofukai Medical Research Institute, Osaka, Japan
| | - Hirotake Sawada
- Division of Pediatrics, Department of Developmental and Urological-Reproductive Medicine, Faculty of Medicine, University of Miyazaki, Miyazaki, Japan
| | - Yoshiro Suzuki
- Division of Cell Signaling, National Institute for Physiological Sciences, National Institutes of Natural Sciences, Okazaki, Japan
| | - Daisuke Hata
- Department of Pediatrics, Kitano Hospital, Tazuke Kofukai Medical Research Institute, Osaka, Japan
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Marx SJ, Goltzman D. Evolution of Our Understanding of the Hyperparathyroid Syndromes: A Historical Perspective. J Bone Miner Res 2019; 34:22-37. [PMID: 30536424 PMCID: PMC6396287 DOI: 10.1002/jbmr.3650] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/16/2018] [Revised: 11/14/2018] [Accepted: 11/20/2018] [Indexed: 12/19/2022]
Abstract
We review advancing and overlapping stages for our understanding of the expressions of six hyperparathyroid (HPT) syndromes: multiple endocrine neoplasia type 1 (MEN1) or type 4, multiple endocrine neoplasia type 2A (MEN2A), hyperparathyroidism-jaw tumor syndrome, familial hypocalciuric hypercalcemia, neonatal severe primary hyperparathyroidism, and familial isolated hyperparathyroidism. During stage 1 (1903 to 1967), the introduction of robust measurement of serum calcium was a milestone that uncovered hypercalcemia as the first sign of dysfunction in many HPT subjects, and inheritability was reported in each syndrome. The earliest reports of HPT syndromes were biased toward severe or striking manifestations. During stage 2 (1959 to 1985), the early formulations of a syndrome were improved. Radioimmunoassays (parathyroid hormone [PTH], gastrin, insulin, prolactin, calcitonin) were breakthroughs. They could identify a syndrome carrier, indicate an emerging tumor, characterize a tumor, or monitor a tumor. During stage 3 (1981 to 2006), the assembly of many cases enabled recognition of further details. For example, hormone non-secreting skin lesions were discovered in MEN1 and MEN2A. During stage 4 (1985 to the present), new genomic tools were a revolution for gene identification. Four principal genes ("principal" implies mutated or deleted in 50% or more probands for its syndrome) (MEN1, RET, CASR, CDC73) were identified for five syndromes. During stage 5 (1993 to the present), seven syndromal genes other than a principal gene were identified (CDKN1B, CDKN2B, CDKN2C, CDKN1A, GNA11, AP2S1, GCM2). Identification of AP2S1 and GCM2 became possible because of whole-exome sequencing. During stages 4 and 5, the newly identified genes enabled many studies, including robust assignment of the carriers and non-carriers of a mutation. Furthermore, molecular pathways of RET and the calcium-sensing receptor were elaborated, thereby facilitating developments in pharmacotherapy. Current findings hold the promise that more genes for HPT syndromes will be identified and studied in the near future. © 2018 American Society for Bone and Mineral Research.
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Affiliation(s)
- Stephen J Marx
- Office of the Scientific Director, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, USA
| | - David Goltzman
- Calcium Research Laboratory, Metabolic Disorders and Complications Program, Research Institute of the McGill University Health Centre, Montreal, Canada
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