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Höppner J, Jüppner H. Rare genetic disorders that impair parathyroid hormone synthesis, secretion, or bioactivity provide insights into the diagnostic utility of different parathyroid hormone assays. Curr Opin Nephrol Hypertens 2024; 33:375-382. [PMID: 38701324 DOI: 10.1097/mnh.0000000000000999] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/05/2024]
Abstract
PURPOSE OF REVIEW Parathyroid hormone (PTH) is the major peptide hormone regulator of blood calcium homeostasis. Abnormal PTH levels can be observed in patients with various congenital and acquired disorders, including chronic kidney disease (CKD). This review will focus on rare human diseases caused by PTH mutations that have provided insights into the regulation of PTH synthesis and secretion as well as the diagnostic utility of different PTH assays. RECENT FINDINGS Over the past years, numerous diseases affecting calcium and phosphate homeostasis have been defined at the molecular level that are responsible for reduced or increased serum PTH levels. The underlying genetic mutations impair parathyroid gland development, involve the PTH gene itself, or alter function of the calcium-sensing receptor (CaSR) or its downstream signaling partners that contribute to regulation of PTH synthesis or secretion. Mutations in the pre sequence of the mature PTH peptide can, for instance, impair hormone synthesis or intracellular processing, while amino acid substitutions affecting the secreted PTH(1-84) impair PTH receptor (PTH1R) activation, or cause defective cleavage of the pro-sequence and thus secretion of a pro- PTH with much reduced biological activity. Mutations affecting the secreted hormone can alter detection by different PTH assays, thus requiring detailed knowledge of the utilized diagnostic test. SUMMARY Rare diseases affecting PTH synthesis and secretion have offered helpful insights into parathyroid biology and the diagnostic utility of commonly used PTH assays, which may have implications for the interpretation of PTH measurements in more common disorders such as CKD.
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Affiliation(s)
| | - Harald Jüppner
- Endocrine Unit
- Pediatric Nephrology Unit, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts, USA
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Küng CJ, Daryadel A, Fuente R, Haykir B, de Angelis MH, Hernando N, Rubio-Aliaga I, Wagner CA. A novel mouse model for familial hypocalciuric hypercalcemia (FHH1) reveals PTH-dependent and independent CaSR defects. Pflugers Arch 2024; 476:833-845. [PMID: 38386045 PMCID: PMC11033242 DOI: 10.1007/s00424-024-02927-y] [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: 12/19/2023] [Revised: 02/11/2024] [Accepted: 02/12/2024] [Indexed: 02/23/2024]
Abstract
The Calcium-sensing receptor (CaSR) senses extracellular calcium, regulates parathyroid hormone (PTH) secretion, and has additional functions in various organs related to systemic and local calcium and mineral homeostasis. Familial hypocalciuric hypercalcemia type I (FHH1) is caused by heterozygous loss-of-function mutations in the CaSR gene, and is characterized by the combination of hypercalcemia, hypocalciuria, normal to elevated PTH, and facultatively hypermagnesemia and mild bone mineralization defects. To date, only heterozygous Casr null mice have been available as model for FHH1. Here we present a novel mouse FHH1 model identified in a large ENU-screen that carries an c.2579 T > A (p.Ile859Asn) variant in the Casr gene (CasrBCH002 mice). In order to dissect direct effects of the genetic variant from PTH-dependent effects, we crossed CasrBCH002 mice with PTH deficient mice. Heterozygous CasrBCH002 mice were fertile, had normal growth and body weight, were hypercalcemic and hypermagnesemic with inappropriately normal PTH levels and urinary calcium excretion replicating some features of FHH1. Hypercalcemia and hypermagnesemia were independent from PTH and correlated with higher expression of claudin 16 and 19 in kidneys. Likewise, reduced expression of the renal TRPM6 channel in CasrBCH002 mice was not dependent on PTH. In bone, mutations in Casr rescued the bone phenotype observed in Pth null mice by increasing osteoclast numbers and improving the columnar pattern of chondrocytes in the growth zone. In summary, CasrBCH002 mice represent a new model to study FHH1 and our results indicate that only a part of the phenotype is driven by PTH.
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Affiliation(s)
- Catharina J Küng
- Institute of Physiology, University of Zürich, Winterthurerstrasse 190, CH-8057, Zurich, Switzerland
| | - Arezoo Daryadel
- Institute of Physiology, University of Zürich, Winterthurerstrasse 190, CH-8057, Zurich, Switzerland
| | - Rocio Fuente
- Institute of Physiology, University of Zürich, Winterthurerstrasse 190, CH-8057, Zurich, Switzerland
- Department of Morphology and Cellular Biology, University of Oviedo, Oviedo, Spain
| | - Betül Haykir
- Institute of Physiology, University of Zürich, Winterthurerstrasse 190, CH-8057, Zurich, Switzerland
| | - Martin Hrabĕ de Angelis
- Institute of Experimental Genetics, Helmholtz Zentrum München, German Research Center for Environmental Health, Neuherberg, Germany
- Lehrstuhl Für Experimentelle Genetik, Technische Universität München, Freising-Weihenstephan, Germany
- Member of German Center for Diabetes Research (DZD), Neuherberg, Germany
| | - Nati Hernando
- Institute of Physiology, University of Zürich, Winterthurerstrasse 190, CH-8057, Zurich, Switzerland
| | - Isabel Rubio-Aliaga
- Institute of Physiology, University of Zürich, Winterthurerstrasse 190, CH-8057, Zurich, Switzerland
| | - Carsten A Wagner
- Institute of Physiology, University of Zürich, Winterthurerstrasse 190, CH-8057, Zurich, Switzerland.
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Yahyavi SK, Boisen IM, Cui Z, Jorsal MJ, Kooij I, Holt R, Juul A, Blomberg Jensen M. Calcium and vitamin D homoeostasis in male fertility. Proc Nutr Soc 2024; 83:95-108. [PMID: 38072394 DOI: 10.1017/s002966512300486x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2023]
Abstract
Calcium and vitamin D have well-established roles in maintaining calcium balance and bone health. Decades of research in human subjects and animals have revealed that calcium and vitamin D also have effects on many other organs including male reproductive organs. The presence of calcium-sensing receptor, vitamin D receptor, vitamin D activating and inactivating enzymes and calcium channels in the testes, male reproductive tract and human spermatozoa suggests that vitamin D and calcium may modify male reproductive function. Functional animal models have shown that vitamin D deficiency in male rodents leads to a decrease in successful mating and fewer pregnancies, often caused by impaired sperm motility and poor sperm morphology. Human studies have to a lesser extent validated these findings; however, newer studies suggest a positive effect of vitamin D supplementation on semen quality in cases with vitamin D deficiency, which highlights the need for initiatives to prevent vitamin D deficiency. Calcium channels in male reproductive organs and spermatozoa contribute to the regulation of sperm motility and capacitation, both essential for successful fertilisation, which supports a need to avoid calcium deficiency. Studies have demonstrated that vitamin D, as a regulator of calcium homoeostasis, influences calcium influx in the testis and spermatozoa. Emerging evidence suggests a potential link between vitamin D deficiency and male infertility, although further investigation is needed to establish a definitive causal relationship. Understanding the interplay between vitamin D, calcium and male reproductive health may open new avenues for improving fertility outcomes in men.
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Affiliation(s)
- Sam Kafai Yahyavi
- Division of Translational Endocrinology, Department of Endocrinology and Internal Medicine, Copenhagen University Hospital - Herlev and Gentofte, Herlev, Denmark
- Group of Skeletal, Mineral, and Gonadal Endocrinology, Department of Growth and Reproduction, Copenhagen University Hospital - Rigshospitalet, Copenhagen, Denmark
| | - Ida Marie Boisen
- Division of Translational Endocrinology, Department of Endocrinology and Internal Medicine, Copenhagen University Hospital - Herlev and Gentofte, Herlev, Denmark
- Group of Skeletal, Mineral, and Gonadal Endocrinology, Department of Growth and Reproduction, Copenhagen University Hospital - Rigshospitalet, Copenhagen, Denmark
| | - Zhihui Cui
- Division of Translational Endocrinology, Department of Endocrinology and Internal Medicine, Copenhagen University Hospital - Herlev and Gentofte, Herlev, Denmark
- Group of Skeletal, Mineral, and Gonadal Endocrinology, Department of Growth and Reproduction, Copenhagen University Hospital - Rigshospitalet, Copenhagen, Denmark
| | - Mads Joon Jorsal
- Division of Translational Endocrinology, Department of Endocrinology and Internal Medicine, Copenhagen University Hospital - Herlev and Gentofte, Herlev, Denmark
- Group of Skeletal, Mineral, and Gonadal Endocrinology, Department of Growth and Reproduction, Copenhagen University Hospital - Rigshospitalet, Copenhagen, Denmark
| | - Ireen Kooij
- Division of Translational Endocrinology, Department of Endocrinology and Internal Medicine, Copenhagen University Hospital - Herlev and Gentofte, Herlev, Denmark
- Group of Skeletal, Mineral, and Gonadal Endocrinology, Department of Growth and Reproduction, Copenhagen University Hospital - Rigshospitalet, Copenhagen, Denmark
| | - Rune Holt
- Division of Translational Endocrinology, Department of Endocrinology and Internal Medicine, Copenhagen University Hospital - Herlev and Gentofte, Herlev, Denmark
- Group of Skeletal, Mineral, and Gonadal Endocrinology, Department of Growth and Reproduction, Copenhagen University Hospital - Rigshospitalet, Copenhagen, Denmark
| | - Anders Juul
- Department of Growth and Reproduction, Copenhagen University Hospital - Rigshospitalet, Copenhagen, Denmark
- International Centre for Research and Research Training in Endocrine Disruption of Male Reproduction and Child Health (EDMaRC), Copenhagen University Hospital - Rigshospitalet, Copenhagen, Denmark
- Department of Clinical Medicine, Copenhagen University Hospital - Rigshospitalet, Copenhagen, Denmark
| | - Martin Blomberg Jensen
- Division of Translational Endocrinology, Department of Endocrinology and Internal Medicine, Copenhagen University Hospital - Herlev and Gentofte, Herlev, Denmark
- Group of Skeletal, Mineral, and Gonadal Endocrinology, Department of Growth and Reproduction, Copenhagen University Hospital - Rigshospitalet, Copenhagen, Denmark
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Sinigaglia B, Escudero J, Biagini SA, Garcia-Calleja J, Moreno J, Dobon B, Acosta S, Mondal M, Walsh S, Aguileta G, Vallès M, Forrow S, Martin-Caballero J, Migliano AB, Bertranpetit J, Muñoz FJ, Bosch E. Exploring Adaptive Phenotypes for the Human Calcium-Sensing Receptor Polymorphism R990G. Mol Biol Evol 2024; 41:msae015. [PMID: 38285634 PMCID: PMC10859840 DOI: 10.1093/molbev/msae015] [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: 01/18/2024] [Revised: 01/23/2024] [Accepted: 01/23/2024] [Indexed: 01/31/2024] Open
Abstract
Rainforest hunter-gatherers from Southeast Asia are characterized by specific morphological features including a particularly dark skin color (D), short stature (S), woolly hair (W), and the presence of steatopygia (S)-fat accumulation localized in the hips (DSWS phenotype). Based on previous evidence in the Andamanese population, we first characterized signatures of adaptive natural selection around the calcium-sensing receptor gene in Southeast Asian rainforest groups presenting the DSWS phenotype and identified the R990G substitution (rs1042636) as a putative adaptive variant for experimental follow-up. Although the calcium-sensing receptor has a critical role in calcium homeostasis by directly regulating the parathyroid hormone secretion, it is expressed in different tissues and has been described to be involved in many biological functions. Previous works have also characterized the R990G substitution as an activating polymorphism of the calcium-sensing receptor associated with hypocalcemia. Therefore, we generated a knock-in mouse for this substitution and investigated organismal phenotypes that could have become adaptive in rainforest hunter-gatherers from Southeast Asia. Interestingly, we found that mouse homozygous for the derived allele show not only lower serum calcium concentration but also greater body weight and fat accumulation, probably because of enhanced preadipocyte differentiation and lipolysis impairment resulting from the calcium-sensing receptor activation mediated by R990G. We speculate that such differential features in humans could have facilitated the survival of hunter-gatherer groups during periods of nutritional stress in the challenging conditions of the Southeast Asian tropical rainforests.
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Affiliation(s)
- Barbara Sinigaglia
- Institut de Biologia Evolutiva (UPF-CSIC), Departament de Medicina i Ciències de la Vida, Universitat Pompeu Fabra, Parc de Recerca Biomèdica de Barcelona, Barcelona 08003, Spain
| | - Jorge Escudero
- Institut de Biologia Evolutiva (UPF-CSIC), Departament de Medicina i Ciències de la Vida, Universitat Pompeu Fabra, Parc de Recerca Biomèdica de Barcelona, Barcelona 08003, Spain
| | - Simone A Biagini
- Institut de Biologia Evolutiva (UPF-CSIC), Departament de Medicina i Ciències de la Vida, Universitat Pompeu Fabra, Parc de Recerca Biomèdica de Barcelona, Barcelona 08003, Spain
| | - Jorge Garcia-Calleja
- Institut de Biologia Evolutiva (UPF-CSIC), Departament de Medicina i Ciències de la Vida, Universitat Pompeu Fabra, Parc de Recerca Biomèdica de Barcelona, Barcelona 08003, Spain
| | - Josep Moreno
- PCB-PRBB Animal Facility Alliance, Parc de Recerca Biomèdica de Barcelona, Barcelona 08003, Spain
| | - Begoña Dobon
- Institut de Biologia Evolutiva (UPF-CSIC), Departament de Medicina i Ciències de la Vida, Universitat Pompeu Fabra, Parc de Recerca Biomèdica de Barcelona, Barcelona 08003, Spain
| | - Sandra Acosta
- Institut de Biologia Evolutiva (UPF-CSIC), Departament de Medicina i Ciències de la Vida, Universitat Pompeu Fabra, Parc de Recerca Biomèdica de Barcelona, Barcelona 08003, Spain
- UB Institute of Neuroscience, Department of Pathology and Experimental Therapeutics, Universitat de Barcelona, Barcelona 08007, Spain
| | - Mayukh Mondal
- Institute of Genomics, University of Tartu, Tartu 51010, Estonia
- Institute of Clinical Molecular Biology, Christian-Albrechts-Universität zu Kiel, Kiel 24118, Germany
| | - Sandra Walsh
- Institut de Biologia Evolutiva (UPF-CSIC), Departament de Medicina i Ciències de la Vida, Universitat Pompeu Fabra, Parc de Recerca Biomèdica de Barcelona, Barcelona 08003, Spain
| | - Gabriela Aguileta
- Institut de Biologia Evolutiva (UPF-CSIC), Departament de Medicina i Ciències de la Vida, Universitat Pompeu Fabra, Parc de Recerca Biomèdica de Barcelona, Barcelona 08003, Spain
| | - Mònica Vallès
- Institut de Biologia Evolutiva (UPF-CSIC), Departament de Medicina i Ciències de la Vida, Universitat Pompeu Fabra, Parc de Recerca Biomèdica de Barcelona, Barcelona 08003, Spain
| | - Stephen Forrow
- Mouse Mutant Core Facility, Institute for Research in Biomedicine (IRB), Barcelona 08028, Spain
| | - Juan Martin-Caballero
- PCB-PRBB Animal Facility Alliance, Parc de Recerca Biomèdica de Barcelona, Barcelona 08003, Spain
| | - Andrea Bamberg Migliano
- Human Evolutionary Ecology Group, Department of Evolutionary Anthropology, University of Zurich, Zurich 8057, Switzerland
| | - Jaume Bertranpetit
- Institut de Biologia Evolutiva (UPF-CSIC), Departament de Medicina i Ciències de la Vida, Universitat Pompeu Fabra, Parc de Recerca Biomèdica de Barcelona, Barcelona 08003, Spain
| | - Francisco J Muñoz
- Laboratory of Molecular Physiology, Departament de Medicina i Ciències de la Vida, Universitat Pompeu Fabra, Parc de Recerca Biomèdica de Barcelona, Barcelona 08003, Spain
| | - Elena Bosch
- Institut de Biologia Evolutiva (UPF-CSIC), Departament de Medicina i Ciències de la Vida, Universitat Pompeu Fabra, Parc de Recerca Biomèdica de Barcelona, Barcelona 08003, Spain
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5
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Jha S, Simonds WF. Molecular and Clinical Spectrum of Primary Hyperparathyroidism. Endocr Rev 2023; 44:779-818. [PMID: 36961765 PMCID: PMC10502601 DOI: 10.1210/endrev/bnad009] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/17/2022] [Revised: 02/09/2023] [Accepted: 03/17/2023] [Indexed: 03/25/2023]
Abstract
Recent data suggest an increase in the overall incidence of parathyroid disorders, with primary hyperparathyroidism (PHPT) being the most prevalent parathyroid disorder. PHPT is associated with morbidities (fractures, kidney stones, chronic kidney disease) and increased risk of death. The symptoms of PHPT can be nonspecific, potentially delaying the diagnosis. Approximately 15% of patients with PHPT have an underlying heritable form of PHPT that may be associated with extraparathyroidal manifestations, requiring active surveillance for these manifestations as seen in multiple endocrine neoplasia type 1 and 2A. Genetic testing for heritable forms should be offered to patients with multiglandular disease, recurrent PHPT, young onset PHPT (age ≤40 years), and those with a family history of parathyroid tumors. However, the underlying genetic cause for the majority of patients with heritable forms of PHPT remains unknown. Distinction between sporadic and heritable forms of PHPT is useful in surgical planning for parathyroidectomy and has implications for the family. The genes currently known to be associated with heritable forms of PHPT account for approximately half of sporadic parathyroid tumors. But the genetic cause in approximately half of the sporadic parathyroid tumors remains unknown. Furthermore, there is no systemic therapy for parathyroid carcinoma, a rare but potentially fatal cause of PHPT. Improved understanding of the molecular characteristics of parathyroid tumors will allow us to identify biomarkers for diagnosis and novel targets for therapy.
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Affiliation(s)
- Smita Jha
- Metabolic Diseases Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892-1752, USA
| | - William F Simonds
- Metabolic Diseases Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892-1752, USA
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6
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Kameda Y. Cellular and molecular mechanisms of the organogenesis and development, and function of the mammalian parathyroid gland. Cell Tissue Res 2023; 393:425-442. [PMID: 37410127 DOI: 10.1007/s00441-023-03785-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2022] [Accepted: 05/12/2023] [Indexed: 07/07/2023]
Abstract
Serum calcium homeostasis is mainly regulated by parathormone (PTH) secreted by the parathyroid gland. Besides PTH and Gcm2, a master gene for parathyroid differentiation, many genes are expressed in the gland. Especially, calcium-sensing receptor (CaSR), vitamin D receptor (VDR), and Klotho function to prevent increased secretion of PTH and hyperplasia of the parathyroid gland under chronic hypocalcemia. Parathyroid-specific dual deletion of Klotho and CaSR induces a marked enlargement of the glandular size. The parathyroid develops from the third and fourth pharyngeal pouches except murine species in which the gland is derived from the third pouch only. The development of the murine parathyroid gland is categorized as follows: (1) formation and differentiation of the pharyngeal pouches, (2) appearance of parathyroid domain in the third pharyngeal pouch together with thymus domain, (3) migration of parathyroid primordium attached to the top of thymus, and (4) contact with the thyroid lobe and separation from the thymus. The transcription factors and signaling molecules involved in each of these developmental stages are elaborated. In addition, mesenchymal neural crest cells surrounding the pharyngeal pouches and parathyroid primordium and invading the parathyroid parenchyma participate in the development of the gland.
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Affiliation(s)
- Yoko Kameda
- Department of Anatomy, Kitasato University School of Medicine, Sagamihara, Kanagawa, 252-0374, Japan.
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7
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Meyer MB, Pike JW. Genomic mechanisms controlling renal vitamin D metabolism. J Steroid Biochem Mol Biol 2023; 228:106252. [PMID: 36657729 PMCID: PMC10006327 DOI: 10.1016/j.jsbmb.2023.106252] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/03/2023] [Accepted: 01/15/2023] [Indexed: 01/18/2023]
Abstract
Vitamin D metabolism centers on regulation in the kidney of CYP27B1 induction by PTH, suppression by FGF23 and 1,25(OH)2D3, and reciprocal CYP24A1 suppression by PTH, and induction by FGF23 and 1,25(OH)2D3. This coordinated genomic regulation through enhancer modules results in the production and dynamic maintenance of circulating endocrine 1,25(OH)2D3 which, together with PTH and FGF23, controls mineral homeostasis. We discovered enhancers near Cyp27b1 in the mouse kidney located within intronic regions of Mettl1 and Mettl21b genes. These kidney-specific enhancers ("M1", "M21") control Cyp27b1. Through CRISPR/Cas deletion, we found that PTH activation of Cyp27b1 is lost with deletion of M1, whereas FGF23 suppression is lost with deletion of M21. The combination of both deletions (M1/M21-DIKO) eliminated the suppression by 1,25(OH)2D3. Cyp24a1 activation by 1,25(OH)2D3 is controlled by a promoter proximal pair of VDREs as well as a distal region - 35 to - 37 kb (DS2). We also found that FGF23 activation and PTH suppression of Cyp24a1 was located in a region - 21 to - 37 kb downstream (DS1). More recently, using in vivo ChIP-seq in mouse kidney, we demonstrate that PTH activation rapidly induces increased recruitment of pCREB and its coactivators, CBP and CRTC2, to the M1 and M21 enhancers near the Cyp27b1 gene. At distal enhancers of the Cyp24a1 gene, PTH suppression promotes dismisses CBP with only minor changes in pCREB and CRTC2 occupancy, all of which correlate with a suppression of basal histone acetylation across this locus and reduced transcripts. Surprisingly, we find that 1,25(OH)2D3 suppression increases the occupancy of CRTC2 in the M1 enhancer, a novel observation for CRTC2 and/or 1,25(OH)2D3 action. The suppressive actions of 1,25(OH)2D3 and FGF23 at the Cyp27b1 gene are associated with a reduction in CBP recruitment at these enhancers. Although FGF23-regulated transcription factors remain unknown, we hypothesize that VDR occupancy induced at the M1 and M21 enhancers by 1,25(OH)2D3 likely disrupts or competes with the active conformation of these CREB modules thereby preventing full induction by PTH. Our findings show coactivators such as CRTC2 and CBP contribute to Cyp27b1 and Cyp24a1 transcription and provide molecular insight into the coordinated mechanistic actions of PTH, FGF23, and 1,25(OH)2D3 in the kidney that regulate mineral homeostasis.
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Affiliation(s)
- Mark B Meyer
- Department of Nutritional Sciences, University of Wisconsin-Madison, Madison, WI 53706, USA; Department of Biochemistry, University of Wisconsin-Madison, Madison, WI 53706, USA.
| | - J Wesley Pike
- Department of Biochemistry, University of Wisconsin-Madison, Madison, WI 53706, USA
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8
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Houillier P, Lievre L, Hureaux M, Prot-Bertoye C. Mechanisms of paracellular transport of magnesium in intestinal and renal epithelia. Ann N Y Acad Sci 2023; 1521:14-31. [PMID: 36622354 DOI: 10.1111/nyas.14953] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Magnesium is the fourth most abundant cation in the body. It plays a critical role in many biological processes, including the process of energy release. Paracellular transport of magnesium is mandatory for magnesium homeostasis. In addition to intestinal absorption that occurs in part across the paracellular pathway, magnesium is reabsorbed by the kidney tubule. The bulk of magnesium is reabsorbed through the paracellular pathway in the proximal tubule and the thick ascending limb of the loop of Henle. The finding that rare genetic diseases due to pathogenic variants in genes encoding specific claudins (CLDNs), proteins located at the tight junction that determine the selectivity and the permeability of the paracellular pathway, led to an awareness of their importance in magnesium homeostasis. Familial hypomagnesemia with hypercalciuria and nephrocalcinosis is caused by a loss of function of CLDN16 or CLDN19. Pathogenic CLDN10 variants cause HELIX syndrome, which is associated with a severe renal loss of sodium chloride and hypermagnesemia. The present review summarizes the current knowledge of the mechanisms and factors involved in paracellular magnesium permeability. The review also highlights some of the unresolved questions that need to be addressed.
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Affiliation(s)
- Pascal Houillier
- Centre de Recherche des Cordeliers, INSERM, Sorbonne Université, Université Paris Cité, Paris, France
- CNRS ERL 8228 - Laboratoire de Physiologie Rénale et Tubulopathies, Paris, France
- Assistance Publique-Hôpitaux de Paris, Hôpital Européen Georges Pompidou, Service de Physiologie, Paris, France
- Centre de Référence des Maladies Rénales Héréditaires de l'Enfant et de l'Adulte (MARHEA), Paris, France
- Centre de Référence des Maladies Rares du Calcium et du Phosphate, Paris, France
| | - Loïc Lievre
- Centre de Recherche des Cordeliers, INSERM, Sorbonne Université, Université Paris Cité, Paris, France
- CNRS ERL 8228 - Laboratoire de Physiologie Rénale et Tubulopathies, Paris, France
| | - Marguerite Hureaux
- Centre de Référence des Maladies Rénales Héréditaires de l'Enfant et de l'Adulte (MARHEA), Paris, France
- Assistance Publique-Hôpitaux de Paris, Hôpital Européen Georges Pompidou, Service de Génétique, Paris, France
- Paris Centre de Recherche Cardio-vasculaire, INSERM, Université Paris Cité, Paris, France
| | - Caroline Prot-Bertoye
- Centre de Recherche des Cordeliers, INSERM, Sorbonne Université, Université Paris Cité, Paris, France
- CNRS ERL 8228 - Laboratoire de Physiologie Rénale et Tubulopathies, Paris, France
- Assistance Publique-Hôpitaux de Paris, Hôpital Européen Georges Pompidou, Service de Physiologie, Paris, France
- Centre de Référence des Maladies Rénales Héréditaires de l'Enfant et de l'Adulte (MARHEA), Paris, France
- Centre de Référence des Maladies Rares du Calcium et du Phosphate, Paris, France
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9
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Gong Y, Yang B, Zhang D, Zhang Y, Tang Z, Yang L, Coate KC, Yin L, Covington BA, Patel RS, Siv WA, Sellick K, Shou M, Chang W, Danielle Dean E, Powers AC, Chen W. Hyperaminoacidemia induces pancreatic α cell proliferation via synergism between the mTORC1 and CaSR-Gq signaling pathways. Nat Commun 2023; 14:235. [PMID: 36646689 PMCID: PMC9842633 DOI: 10.1038/s41467-022-35705-4] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2021] [Accepted: 12/20/2022] [Indexed: 01/18/2023] Open
Abstract
Glucagon has emerged as a key regulator of extracellular amino acid (AA) homeostasis. Insufficient glucagon signaling results in hyperaminoacidemia, which drives adaptive proliferation of glucagon-producing α cells. Aside from mammalian target of rapamycin complex 1 (mTORC1), the role of other AA sensors in α cell proliferation has not been described. Here, using both genders of mouse islets and glucagon receptor (gcgr)-deficient zebrafish (Danio rerio), we show α cell proliferation requires activation of the extracellular signal-regulated protein kinase (ERK1/2) by the AA-sensitive calcium sensing receptor (CaSR). Inactivation of CaSR dampened α cell proliferation, which was rescued by re-expression of CaSR or activation of Gq, but not Gi, signaling in α cells. CaSR was also unexpectedly necessary for mTORC1 activation in α cells. Furthermore, coactivation of Gq and mTORC1 induced α cell proliferation independent of hyperaminoacidemia. These results reveal another AA-sensitive mediator and identify pathways necessary and sufficient for hyperaminoacidemia-induced α cell proliferation.
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Affiliation(s)
- Yulong Gong
- Department of Molecular Physiology & Biophysics, Vanderbilt University, 2215 Garland Ave, Nashville, TN, 37232, USA
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, Hubei, 430072, China
| | - Bingyuan Yang
- Department of Molecular Physiology & Biophysics, Vanderbilt University, 2215 Garland Ave, Nashville, TN, 37232, USA
| | - Dingdong Zhang
- Department of Molecular Physiology & Biophysics, Vanderbilt University, 2215 Garland Ave, Nashville, TN, 37232, USA
- College of Animal Science and Technology, Nanjing Agricultural University, Nanjing, 210095, China
| | - Yue Zhang
- Department of Molecular Physiology & Biophysics, Vanderbilt University, 2215 Garland Ave, Nashville, TN, 37232, USA
| | - Zihan Tang
- Department of Molecular Physiology & Biophysics, Vanderbilt University, 2215 Garland Ave, Nashville, TN, 37232, USA
| | - Liu Yang
- Department of Molecular Physiology & Biophysics, Vanderbilt University, 2215 Garland Ave, Nashville, TN, 37232, USA
| | - Katie C Coate
- Division of Diabetes, Endocrinology and Metabolism, Department of Medicine, Vanderbilt University Medical Center, 2215 Garland Ave, Nashville, TN, 37232, USA
| | - Linlin Yin
- Department of Molecular Physiology & Biophysics, Vanderbilt University, 2215 Garland Ave, Nashville, TN, 37232, USA
| | - Brittney A Covington
- Department of Molecular Physiology & Biophysics, Vanderbilt University, 2215 Garland Ave, Nashville, TN, 37232, USA
| | - Ravi S Patel
- Department of Molecular Physiology & Biophysics, Vanderbilt University, 2215 Garland Ave, Nashville, TN, 37232, USA
| | - Walter A Siv
- Division of Diabetes, Endocrinology and Metabolism, Department of Medicine, Vanderbilt University Medical Center, 2215 Garland Ave, Nashville, TN, 37232, USA
| | - Katelyn Sellick
- Division of Diabetes, Endocrinology and Metabolism, Department of Medicine, Vanderbilt University Medical Center, 2215 Garland Ave, Nashville, TN, 37232, USA
| | - Matthew Shou
- Division of Diabetes, Endocrinology and Metabolism, Department of Medicine, Vanderbilt University Medical Center, 2215 Garland Ave, Nashville, TN, 37232, USA
| | - Wenhan Chang
- University of California San Francisco and San Francisco VA Medical Center, San Francisco, CA, 94158, USA
| | - E Danielle Dean
- Department of Molecular Physiology & Biophysics, Vanderbilt University, 2215 Garland Ave, Nashville, TN, 37232, USA
- Division of Diabetes, Endocrinology and Metabolism, Department of Medicine, Vanderbilt University Medical Center, 2215 Garland Ave, Nashville, TN, 37232, USA
| | - Alvin C Powers
- Department of Molecular Physiology & Biophysics, Vanderbilt University, 2215 Garland Ave, Nashville, TN, 37232, USA
- Division of Diabetes, Endocrinology and Metabolism, Department of Medicine, Vanderbilt University Medical Center, 2215 Garland Ave, Nashville, TN, 37232, USA
- VA Tennessee Valley Healthcare System, Nashville, TN, 37212, USA
| | - Wenbiao Chen
- Department of Molecular Physiology & Biophysics, Vanderbilt University, 2215 Garland Ave, Nashville, TN, 37232, USA.
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10
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Sharma A, Memon S, Lila AR, Sarathi V, Arya S, Jadhav SS, Hira P, Garale M, Gosavi V, Karlekar M, Patil V, Bandgar T. Genotype-Phenotype Correlations in Asian Indian Children and Adolescents with Primary Hyperparathyroidism. Calcif Tissue Int 2022; 111:229-241. [PMID: 35567607 DOI: 10.1007/s00223-022-00985-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/06/2022] [Accepted: 04/26/2022] [Indexed: 11/02/2022]
Abstract
Childhood and adolescent primary hyperparathyroidism (PHPT) is a very rare disease. Data on its molecular genetics are scarce. We performed a retrospective analysis (January 2000-January 2021) to determine the deleterious germline variants and genotype-phenotype correlations in children and adolescents < 20 years diagnosed with PHPT from a single referral center. Clinical features, biochemistry, imaging, management, and genetics (clinical exome analyzed for 11 PHPT and 7 pancreatitis-associated genes, MLPA for CDC73) were recorded. Thirty-six patients (20 males; median age 17 years) were classified into those with familial and/or syndromic (F/S) or apparently sporadic (AS) presentation. Sixteen (44.4%) harbored pathogenic/likely pathogenic germline variants in PHPT-associated genes. The genetic yield in F/S group was 90% (MEN1:8/10; CDC73:1/10), and AS group was 26.9% (CDC73:4/26; CASR:3/26). F/S group had frequent asymptomatic presentation (60% vs none; P < 0.001), lower serum PTH (237.5 vs 1369.1 pg/mL; P = 0.001), and maximum parathyroid dimension (0.9 vs 2.2 cm; P = 0.01) than AS group. Among the AS group, renal involvement was higher in those with molecular diagnoses (71.4% vs 10.5%; P = 0.01). All those with novel CASR variants (including one homozygous) had hypercalciuria and histology-proven parathyroid adenoma/carcinoma. A missense CTRC VUS occurred in one patient with chronic pancreatitis. In summary, Asian Indian children and adolescents with PHPT have high genetic yield, even with apparently sporadic presentation. The phenotypic spectrum of CASR variants is expanded to include childhood/adolescent PHPT with hypercalciuria and single gland neoplasia. The proposed roles for renal involvement to predict molecular diagnosis among those with apparently sporadic presentation require further elucidation.
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Affiliation(s)
- Anima Sharma
- Department of Endocrinology, Seth GS Medical College and KEM Hospital, Parel, Mumbai, 400012, India
| | - Saba Memon
- Department of Endocrinology, Seth GS Medical College and KEM Hospital, Parel, Mumbai, 400012, India
| | - Anurag R Lila
- Department of Endocrinology, Seth GS Medical College and KEM Hospital, Parel, Mumbai, 400012, India
| | - Vijaya Sarathi
- Department of Endocrinology, Vydehi Institute of Medical Sciences and Research Centre, Bengaluru, 560066, India
| | - Sneha Arya
- Department of Endocrinology, Seth GS Medical College and KEM Hospital, Parel, Mumbai, 400012, India
| | - Swati S Jadhav
- Department of Endocrinology, Sapthagiri Institute of Medical Sciences and Research Centre, Bengaluru, 560090, India
| | - Priya Hira
- Department of Radiodiagnosis, Seth GS Medical College and KEM Hospital, Parel, Mumbai, India
| | - Mahadeo Garale
- Department of Surgery, Seth GS Medical College and KEM Hospital, Parel, Mumbai, India
| | - Vikrant Gosavi
- Department of Endocrinology, Seth GS Medical College and KEM Hospital, Parel, Mumbai, 400012, India
| | - Manjiri Karlekar
- Department of Endocrinology, Seth GS Medical College and KEM Hospital, Parel, Mumbai, 400012, India
| | - Virendra Patil
- Department of Endocrinology, Seth GS Medical College and KEM Hospital, Parel, Mumbai, 400012, India
| | - Tushar Bandgar
- Department of Endocrinology, Seth GS Medical College and KEM Hospital, Parel, Mumbai, 400012, India.
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11
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Wang X, Lundblad J, Smith SM. Reduced affinity of calcium sensing-receptor heterodimers and reduced mutant homodimer trafficking combine to impair function in a model of familial hypocalciuric hypercalcemia type 1. PLoS One 2022; 17:e0266993. [PMID: 35857775 PMCID: PMC9299317 DOI: 10.1371/journal.pone.0266993] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2022] [Accepted: 06/30/2022] [Indexed: 11/18/2022] Open
Abstract
Heterozygous loss-of-function mutation of the calcium sensing-receptor (CaSR), causes familial hypocalciuric hypercalcemia type 1 (FHH1), a typically benign condition characterized by mild hypercalcemia. In contrast, homozygous mutation of this dimer-forming G-protein coupled receptor manifests as the lethal neonatal severe hyperparathyroidism (NSHPT). To investigate the mechanisms by which CaSR mutations lead to these distinct disease states, we engineered wild-type (WT) and an exon 5-deficient disease-causing mutation, and transfected expression constructs into human embryonic kidney (HEK) cells. WT protein was mainly membrane-expressed whereas the mutant CaSR protein (mCaSR) was confined to the cytoplasm. Co-expression of WT CaSR directed mCaSR to the cell membrane. In assays of CaSR function, increases in extracellular [Ca2+] ([Ca2+]o) increased intracellular [Ca2+] ([Ca2+]i) in cells expressing WT CaSR while the response was reduced in cells co-expressing mutant and WT receptor. Untransfected cells or those expressing mCaSR alone, showed minimal, equivalent responses to increased [Ca2+]o. Immunoprecipitation experiments confirmed an association between mutant and wild-type CaSR. The affinity of the WT CaSR for calcium was three times greater than that of the heterodimer. The maximal functional response to [Ca]o was dependent on localization of CaSR to the membrane level and independent of homo- or heterodimerizations. In summary, these results suggest that heterodimerization of WT and mCaSR receptors, rescues the trafficking defect of the mutant receptors and also reduces the affinity of the WT-mutant heterodimer for [Ca]o. In contrast, the homozygous mutants do not produce functional receptors on cell membrane. These data indicate how substantial differences between signaling of hetero- and homodimeric mutants may lead to profound differences in the severity of disease in heterozygous and homozygous carriers of these mutations.
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Affiliation(s)
- Xiaohua Wang
- Division of Pulmonary and Critical Care Medicine, Oregon Health and Science University, Portland, Oregon, United States of America
| | - James Lundblad
- Division of Endocrinology and Diabetes, Oregon Health and Science University, Portland, Oregon, United States of America
- Section of Endocrinology and Diabetes, VA Portland Health Care System, Portland, Oregon, United States of America
| | - Stephen M. Smith
- Division of Pulmonary and Critical Care Medicine, Oregon Health and Science University, Portland, Oregon, United States of America
- Sections of Pulmonary and Critical Care Medicine and Research & Development, VA Portland Health Care System, Portland, Oregon, United States of America
- * E-mail:
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12
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The importance of kidney calcium handling in the homeostasis of extracellular fluid calcium. Pflugers Arch 2022; 474:885-900. [PMID: 35842482 DOI: 10.1007/s00424-022-02725-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2022] [Revised: 06/09/2022] [Accepted: 06/30/2022] [Indexed: 12/13/2022]
Abstract
Extracellular fluid calcium concentration must be maintained within a narrow range in order to sustain many biological functions, encompassing muscle contraction, blood coagulation, and bone and tooth mineralization. Blood calcium value is critically dependent on the ability of the renal tubule to reabsorb the adequate amount of filtered calcium. Tubular calcium reabsorption is carried out by various and complex mechanisms in 3 distinct segments: the proximal tubule, the cortical thick ascending limb of the loop of Henle, and the late distal convoluted/connecting tubule. In addition, calcium reabsorption is tightly controlled by many endocrine, paracrine, and autocrine factors, as well as by non-hormonal factors, in order to adapt the tubular handling of calcium to the metabolic requirements. The present review summarizes the current knowledge of the mechanisms and factors involved in calcium handling by the kidney and, ultimately, in extracellular calcium homeostasis. The review also highlights some of our gaps in understanding that need to be addressed in the future.
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13
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Li X, Lu Y, Zhang L, Song A, Zhang H, Pang B, Liu J, Sun X, Ji H, Huang L, Yang M. Implications of regulator of G-protein signaling 5 expression in the pathogenesis of primary and secondary hyperparathyroidism. BMC Endocr Disord 2022; 22:156. [PMID: 35681135 PMCID: PMC9185949 DOI: 10.1186/s12902-022-01066-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/17/2022] [Accepted: 05/31/2022] [Indexed: 12/02/2022] Open
Abstract
OBJECTIVE To study the protein and mRNA expressions of regulator of G-protein signaling 5 (RGS5) in the pathogenesis of hyperparathyroidism. METHODS The expression of RGS5 protein in 20 primary hyperparathyroidism (PHPT), 31 secondary hyperparathyroidism (SHPT), and 20 control cases were studied by immunohistochemistry (IHC). The expression of RGS5 mRNA in 15 PHPT, 102 SHPT, and 7 normal parathyroid tissue were measured by quantitative real-time PCR (qRT-PCR) method. RESULTS The expressions of RGS5 in PHPT tissues were significantly higher than that in SHPT and normal parathyroid tissues (P < 0.05). While the differences in RGS5 protein expressions between SHPT and respective control samples were not statistically significant (P > 0.05). Likewise, the RGS5 mRNA expression in PHPT was significantly higher than that in SHPT (P < 0.05) and normal parathyroid (P < 0.05) samples. In a similar line, the differences in RGS5 gene expressions between SHPT and control tissues were not statistically significant (P > 0.05). CONCLUSIONS The characteristic RGS5 protein and mRNA levels in hyperparathyroidism might be helpful in discovering the pathomechanism of hyperparathyroidism and novel therapeutic targets as well.
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Affiliation(s)
- Xin Li
- Institute of Clinical Medicine Research, China-Japan Friendship Hospital, 100029, Beijing, China
| | - Yao Lu
- Department of General Surgery, China-Japan Friendship Hospital, 100029, Beijing, China
| | - Ling Zhang
- Center of Nephrology, China-Japan Friendship Hospital, 100029, Beijing, China
| | - Aiping Song
- Department of Pathology, China-Japan Friendship Hospital, 100029, Beijing, China
| | - Honglei Zhang
- Department of Pathology, China-Japan Friendship Hospital, 100029, Beijing, China
| | - Bo Pang
- State Key Laboratory of Infectious Disease Prevention and Control, National Institute for Communicable Disease Control and Prevention, CDC 155, Changbai Road, Beijing, 102206, Changping, China
| | - Jun Liu
- Department of General Surgery, China-Japan Friendship Hospital, 100029, Beijing, China
| | - Xiaoliang Sun
- Department of General Surgery, China-Japan Friendship Hospital, 100029, Beijing, China
| | - Haoyang Ji
- Department of General Surgery, China-Japan Friendship Hospital, 100029, Beijing, China
| | - Linping Huang
- Department of General Surgery, China-Japan Friendship Hospital, 100029, Beijing, China
| | - Meng Yang
- Department of General Surgery, China-Japan Friendship Hospital, 100029, Beijing, China.
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14
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Schepelmann M, Ranieri M, Lopez-Fernandez I, Webberley TS, Brennan SC, Yarova PL, Graca J, Hanif UK, Müller C, Manhardt T, Salzmann M, Quasnichka H, Price SA, Ward DT, Gilbert T, Matchkov VV, Fenton RA, Herberger A, Hwong J, Santa Maria C, Tu CL, Kallay E, Valenti G, Chang W, Riccardi D. Impaired Mineral Ion Metabolism in a Mouse Model of Targeted Calcium-Sensing Receptor (CaSR) Deletion from Vascular Smooth Muscle Cells. J Am Soc Nephrol 2022; 33:1323-1340. [PMID: 35581010 PMCID: PMC9257819 DOI: 10.1681/asn.2021040585] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2021] [Accepted: 03/07/2022] [Indexed: 11/03/2022] Open
Abstract
BACKGROUND Impaired mineral ion metabolism is a hallmark of CKD-metabolic bone disorder. It can lead to pathologic vascular calcification and is associated with an increased risk of cardiovascular mortality. Loss of calcium-sensing receptor (CaSR) expression in vascular smooth muscle cells exacerbates vascular calcification in vitro. Conversely, vascular calcification can be reduced by calcimimetics, which function as allosteric activators of CaSR. METHODS To determine the role of the CaSR in vascular calcification, we characterized mice with targeted Casr gene knockout in vascular smooth muscle cells ( SM22α CaSR Δflox/Δflox ). RESULTS Vascular smooth muscle cells cultured from the knockout (KO) mice calcified more readily than those from control (wild-type) mice in vitro. However, mice did not show ectopic calcifications in vivo but they did display a profound mineral ion imbalance. Specifically, KO mice exhibited hypercalcemia, hypercalciuria, hyperphosphaturia, and osteopenia, with elevated circulating fibroblast growth factor 23 (FGF23), calcitriol (1,25-D3), and parathyroid hormone levels. Renal tubular α-Klotho protein expression was increased in KO mice but vascular α-Klotho protein expression was not. Altered CaSR expression in the kidney or the parathyroid glands could not account for the observed phenotype of the KO mice. CONCLUSIONS These results suggest that, in addition to CaSR's established role in the parathyroid-kidney-bone axis, expression of CaSR in vascular smooth muscle cells directly contributes to total body mineral ion homeostasis.
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Affiliation(s)
- Martin Schepelmann
- School of Biosciences, Cardiff University, Cardiff, United Kingdom .,Institute of Pathophysiology and Allergy Research, Medical University of Vienna, Vienna, Austria
| | - Marianna Ranieri
- Department of Biosciences, Biotechnologies and Biopharmaceutics, University of Bari, Bari, Italy
| | | | | | - Sarah C Brennan
- School of Biosciences, Cardiff University, Cardiff, United Kingdom.,Charles Perkins Centre, University of Sydney, Sydney, Australia
| | - Polina L Yarova
- School of Biosciences, Cardiff University, Cardiff, United Kingdom.,Translational and Clinical Research Institute, Newcastle University Medical School, Newcastle upon Tyne, United Kingdom
| | - Joao Graca
- School of Biosciences, Cardiff University, Cardiff, United Kingdom.,AstraZeneca, Macclesfield, United Kingdom
| | | | - Christian Müller
- Institute of Pathophysiology and Allergy Research, Medical University of Vienna, Vienna, Austria
| | - Teresa Manhardt
- Institute of Pathophysiology and Allergy Research, Medical University of Vienna, Vienna, Austria
| | - Martina Salzmann
- Institute of Pathophysiology and Allergy Research, Medical University of Vienna, Vienna, Austria
| | - Helen Quasnichka
- School of Biosciences, Cardiff University, Cardiff, United Kingdom
| | | | - Donald T Ward
- Division of Diabetes, Endocrinology, and Gastroenterology, University of Manchester, Manchester, United Kingdom
| | - Thierry Gilbert
- Centre for Developmental Biology, University Paul Sabatier, Toulouse, France
| | | | - Robert A Fenton
- Department of Biomedicine, Aarhus University, Aarhus, Denmark
| | - Amanda Herberger
- Department of Medicine, University of California, San Francisco, California
| | - Jenna Hwong
- Department of Medicine, University of California, San Francisco, California
| | | | - Chia-Ling Tu
- Department of Medicine, University of California, San Francisco, California
| | - Enikö Kallay
- Institute of Pathophysiology and Allergy Research, Medical University of Vienna, Vienna, Austria
| | - Giovanna Valenti
- Department of Biosciences, Biotechnologies and Biopharmaceutics, University of Bari, Bari, Italy
| | - Wenhan Chang
- Department of Medicine, University of California, San Francisco, California
| | - Daniela Riccardi
- School of Biosciences, Cardiff University, Cardiff, United Kingdom
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15
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Mullin BH, Pavlos NJ, Brown SJ, Walsh JP, McKellar RA, Wilson SG, Ward BK. Functional Assessment of Calcium-Sensing Receptor Variants Confirms Familial Hypocalciuric Hypercalcaemia. J Endocr Soc 2022; 6:bvac025. [PMID: 35356007 PMCID: PMC8962451 DOI: 10.1210/jendso/bvac025] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/24/2021] [Indexed: 11/26/2022] Open
Abstract
Context In the clinic it is important to differentiate primary hyperparathyroidism (PHPT) from the more benign, inherited disorder, familial hypocalciuric hypercalcemia (FHH). Since the conditions may sometimes overlap biochemically, identification of calcium-sensing receptor (CASR) gene variants causative of FHH (but not PHPT) is the most decisive diagnostic aid. When novel variants are identified, bioinformatics and functional assessment are required to establish pathogenicity. Objective We identified 3 novel CASR transmembrane domain missense variants, Thr699Asn, Arg701Gly, and Thr808Pro, in 3 probands provisionally diagnosed with FHH and examined the variants using bioinformatics and functional analysis. Methods Bioinformatics assessment utilized wANNOVAR software. For functional characterization, each variant was cloned into a mammalian expression vector; wild-type and variant receptors were transfected into HEK293 cells, and their expression and cellular localization were assessed by Western blotting and confocal immunofluorescence, respectively. Receptor activation in HEK293 cells was determined using an IP-One ELISA assay following stimulation with Ca++ ions. Results Bioinformatics analysis of the variants was unable to definitively assign pathogenicity. Compared with wild-type receptor, all variants demonstrated impaired expression of mature receptor reaching the cell surface and diminished activation at physiologically relevant Ca++ concentrations. Conclusion Three CASR missense variants identified in probands provisionally diagnosed with FHH result in receptor inactivation and are therefore likely causative of FHH. Inactivation may be due to inadequate processing/trafficking of mature receptor and/or conformational changes induced by the variants affecting receptor signaling. This study demonstrates the value of functional studies in assessing genetic variants identified in hypercalcemic patients.
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Affiliation(s)
- Benjamin H Mullin
- Department of Endocrinology and Diabetes, Sir Charles Gairdner Hospital, Nedlands, WA, Australia
- School of Biomedical Sciences, University of Western Australia, Nedlands, WA, Australia
| | - Nathan J Pavlos
- School of Biomedical Sciences, University of Western Australia, Nedlands, WA, Australia
| | - Suzanne J Brown
- Department of Endocrinology and Diabetes, Sir Charles Gairdner Hospital, Nedlands, WA, Australia
| | - John P Walsh
- Department of Endocrinology and Diabetes, Sir Charles Gairdner Hospital, Nedlands, WA, Australia
- Medical School, University of Western Australia, Nedlands, WA, Australia
| | - Ross A McKellar
- Department of Endocrinology and Diabetes, Sir Charles Gairdner Hospital, Nedlands, WA, Australia
| | - Scott G Wilson
- Department of Endocrinology and Diabetes, Sir Charles Gairdner Hospital, Nedlands, WA, Australia
- School of Biomedical Sciences, University of Western Australia, Nedlands, WA, Australia
- Department of Twin Research and Genetic Epidemiology, King’s College London, London, UK
| | - Bryan K Ward
- Department of Endocrinology and Diabetes, Sir Charles Gairdner Hospital, Nedlands, WA, Australia
- Harry Perkins Institute of Medical Research, Centre for Medical Research, QEII Medical Centre, University of Western Australia, Nedlands, WA, Australia
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16
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Irsik DL, Bollag WB, Isales CM. Renal Contributions to Age-Related Changes in Mineral Metabolism. JBMR Plus 2021; 5:e10517. [PMID: 34693188 PMCID: PMC8520061 DOI: 10.1002/jbm4.10517] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/31/2020] [Revised: 04/28/2021] [Accepted: 05/09/2021] [Indexed: 11/10/2022] Open
Abstract
Aging results in a general decline in function in most systems. This is particularly true with respect to the skeleton and renal systems, impacting mineral homeostasis. Calcium and phosphate regulation requires tight coordination among the intestine, bone, parathyroid gland, and kidney. The role of the intestine is to absorb calcium and phosphate from the diet. The bone stores or releases calcium and phosphate depending on the body's needs. In response to low plasma ionized calcium concentration, the parathyroid gland produces parathyroid hormone, which modulates bone turnover. The kidney reabsorbs or excretes the minerals and serves as the final regulator of plasma concentration. Many hormones are involved in this process in addition to parathyroid hormone, including fibroblast growth factor 23 produced by the bone and calcitriol synthesized by the kidney. Sclerostin, calcitonin, osteoprotegerin, and receptor activator of nuclear factor‐κB ligand also contribute to tissue‐specific regulation. Changes in the function of organs due to aging or disease can perturb this balance. During aging, the intestine cannot absorb calcium efficiently due to decreased expression of key proteins. In the bone, the balance between bone formation and bone resorption tends toward the latter in older individuals. The kidney may not filter blood as efficiently in the later decades of life, and the expression of certain proteins necessary for mineral homeostasis declines with age. These changes often lead to dysregulation of organismal mineral homeostasis. This review will focus on how mineral homeostasis is impacted by aging with a particular emphasis on the kidney's role in this process. © 2021 The Authors. JBMR Plus published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research.
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Affiliation(s)
- Debra L Irsik
- Charlie Norwood VA Medical Center Augusta GA USA.,Department of Neuroscience and Regenerative Medicine Augusta University Augusta GA USA
| | - Wendy B Bollag
- Charlie Norwood VA Medical Center Augusta GA USA.,Department of Physiology Augusta University Augusta GA USA
| | - Carlos M Isales
- Department of Neuroscience and Regenerative Medicine Augusta University Augusta GA USA.,Division of Endocrinology, Department of Medicine Augusta University Augusta GA USA
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17
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Salinity-dependent expression of calcium-sensing receptors in Atlantic salmon (Salmo salar) tissues. J Comp Physiol A Neuroethol Sens Neural Behav Physiol 2021; 207:505-522. [PMID: 34114081 DOI: 10.1007/s00359-021-01493-3] [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: 12/31/2020] [Revised: 05/23/2021] [Accepted: 05/26/2021] [Indexed: 10/21/2022]
Abstract
Multiple reports suggest that calcium-sensing receptors (CaSRs) are involved in calcium homeostasis, osmoregulation, and/or salinity sensing in fish (Loretz 2008, Herberger and Loretz 2013). We have isolated three unique full-length CaSR cDNAs from Atlantic salmon (Salmo salar) kidney that share many features with other reported CaSRs. Using anti-CaSR antibodies and PCR primers specific for individual salmon CaSR transcripts we show expression in osmoregulatory, neuroendocrine and sensory tissues. Furthermore, CaSRs are expressed in different patterns in salmon tissues where mRNA and protein expression are modified by freshwater or seawater acclimation. For example, in seawater, CaSR mRNA and protein expression is increased significantly in kidney as compared to freshwater. Electrophysiological recordings of olfactory responses produced upon exposure of salmon olfactory epithelium to CaSR agonists suggest a role for CaSRs in chemoreception in this species consistent with other freshwater, anadromous, and marine species where similar olfactory responses to divalent and polyvalent cations have been reported. These data provide further support for a role of CaSR proteins in osmoregulatory and sensory functions in Atlantic salmon, an anadromous species that experiences a broad range of environmental salinities in its life history.
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18
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Figueres L, Beck-Cormier S, Beck L, Marks J. The Complexities of Organ Crosstalk in Phosphate Homeostasis: Time to Put Phosphate Sensing Back in the Limelight. Int J Mol Sci 2021; 22:5701. [PMID: 34071837 PMCID: PMC8199323 DOI: 10.3390/ijms22115701] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2021] [Revised: 05/13/2021] [Accepted: 05/21/2021] [Indexed: 12/16/2022] Open
Abstract
Phosphate homeostasis is essential for health and is achieved via interaction between the bone, kidney, small intestine, and parathyroid glands and via intricate processes involving phosphate transporters, phosphate sensors, and circulating hormones. Numerous genetic and acquired disorders are associated with disruption in these processes and can lead to significant morbidity and mortality. The role of the kidney in phosphate homeostasis is well known, although it is recognized that the cellular mechanisms in murine models and humans are different. Intestinal phosphate transport also appears to differ in humans and rodents, with recent studies demonstrating a dominant role for the paracellular pathway. The existence of phosphate sensing has been acknowledged for decades; however, the underlying molecular mechanisms are poorly understood. At least three phosphate sensors have emerged. PiT2 and FGFR1c both act as phosphate sensors controlling Fibroblast Growth Factor 23 secretion in bone, whereas the calcium-sensing receptor controls parathyroid hormone secretion in response to extracellular phosphate. All three of the proposed sensors are expressed in the kidney and intestine but their exact function in these organs is unknown. Understanding organ interactions and the mechanisms involved in phosphate sensing requires significant research to develop novel approaches for the treatment of phosphate homeostasis disorders.
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Affiliation(s)
- Lucile Figueres
- Department of Neuroscience, Physiology and Pharmacology, Royal Free Campus, University College London, London NW3 2PF, UK;
- CHU de Nantes, Université de Nantes, F-44042 Nantes, France
| | - Sarah Beck-Cormier
- Inserm, UMR 1229, RMeS Regenerative Medicine and Skeleton, Université de Nantes, ONIRIS, F-44042 Nantes, France; (S.B.-C.); (L.B.)
| | - Laurent Beck
- Inserm, UMR 1229, RMeS Regenerative Medicine and Skeleton, Université de Nantes, ONIRIS, F-44042 Nantes, France; (S.B.-C.); (L.B.)
| | - Joanne Marks
- Department of Neuroscience, Physiology and Pharmacology, Royal Free Campus, University College London, London NW3 2PF, UK;
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19
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Tan RSG, Lee CHL, Dimke H, Todd Alexander R. The role of calcium-sensing receptor signaling in regulating transepithelial calcium transport. Exp Biol Med (Maywood) 2021; 246:2407-2419. [PMID: 33926258 DOI: 10.1177/15353702211010415] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
The calcium-sensing receptor (CaSR) plays a critical role in sensing extracellular calcium (Ca2+) and signaling to maintain Ca2+ homeostasis. In the parathyroid, the CaSR regulates secretion of parathyroid hormone, which functions to increase extracellular Ca2+ levels. The CaSR is also located in other organs imperative to Ca2+ homeostasis including the kidney and intestine, where it modulates Ca2+ reabsorption and absorption, respectively. In this review, we describe CaSR expression and its function in transepithelial Ca2+ transport in the kidney and intestine. Activation of the CaSR leads to G protein dependent and independent signaling cascades. The known CaSR signal transduction pathways involved in modulating paracellular and transcellular epithelial Ca2+ transport are discussed. Mutations in the CaSR cause a range of diseases that manifest in altered serum Ca2+ levels. Gain-of-function mutations in the CaSR result in autosomal dominant hypocalcemia type 1, while loss-of-function mutations cause familial hypocalciuric hypercalcemia. Additionally, the putative serine protease, FAM111A, is discussed as a potential regulator of the CaSR because mutations in FAM111A cause Kenny Caffey syndrome type 2, gracile bone dysplasia, and osteocraniostenosis, diseases that are characterized by hypocalcemia, hypoparathyroidism, and bony abnormalities, i.e. share phenotypic features of autosomal dominant hypocalcemia. Recent work has helped to elucidate the effect of CaSR signaling cascades on downstream proteins involved in Ca2+ transport across renal and intestinal epithelia; however, much remains to be discovered.
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Affiliation(s)
- Rebecca Siu Ga Tan
- Department of Physiology, University of Alberta, Edmonton T6G 1C9, Canada.,Membrane Protein Disease Research Group, University of Alberta, Edmonton T6G 1C9, Canada
| | | | - Henrik Dimke
- Department of Cardiovascular and Renal Research, Institute of Molecular Medicine, University of Southern Denmark, Odense 5000, Denmark.,Department of Nephrology, Odense University Hospital, Odense 5000, Denmark
| | - R Todd Alexander
- Department of Physiology, University of Alberta, Edmonton T6G 1C9, Canada.,Membrane Protein Disease Research Group, University of Alberta, Edmonton T6G 1C9, Canada.,Department of Pediatrics, University of Alberta, Edmonton T6G 1C9, Canada
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20
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Boisen IM, Rehfeld A, Mos I, Poulsen NN, Nielsen JE, Schwarz P, Rejnmark L, Dissing S, Bach-Mortensen P, Juul A, Bräuner-Osborne H, Lanske B, Blomberg Jensen M. The Calcium-Sensing Receptor Is Essential for Calcium and Bicarbonate Sensitivity in Human Spermatozoa. J Clin Endocrinol Metab 2021; 106:e1775-e1792. [PMID: 33340048 DOI: 10.1210/clinem/dgaa937] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/21/2020] [Indexed: 11/19/2022]
Abstract
CONTEXT The calcium-sensing receptor (CaSR) is essential to maintain a stable calcium concentration in serum. Spermatozoa are exposed to immense changes in concentrations of CaSR ligands such as calcium, magnesium, and spermine during epididymal maturation, in the ejaculate, and in the female reproductive environment. However, the role of CaSR in human spermatozoa is unknown. OBJECTIVE This work aimed to investigate the role of CaSR in human spermatozoa. METHODS We identified CaSR in human spermatozoa and characterized the response to CaSR agonists on intracellular calcium, acrosome reaction, and 3',5'-cyclic adenosine 5'-monophosphate (cAMP) in spermatozoa from men with either loss-of-function or gain-of-function mutations in CASR and healthy donors. RESULTS CaSR is expressed in human spermatozoa and is essential for sensing extracellular free ionized calcium (Ca2+) and Mg2+. Activators of CaSR augmented the effect of sperm-activating signals such as the response to HCO3- and the acrosome reaction, whereas spermatozoa from men with a loss-of-function mutation in CASR had a diminished response to HCO3-, lower progesterone-mediated calcium influx, and were less likely to undergo the acrosome reaction in response to progesterone or Ca2+. CaSR activation increased cAMP through soluble adenylyl cyclase (sAC) activity and increased calcium influx through CatSper. Moreover, external Ca2+ or Mg2+ was indispensable for HCO3- activation of sAC. Two male patients with a CASR loss-of-function mutation in exon 3 presented with normal sperm counts and motility, whereas a patient with a loss-of-function mutation in exon 7 had low sperm count, motility, and morphology. CONCLUSION CaSR is important for the sensing of Ca2+, Mg2+, and HCO3- in spermatozoa, and loss-of-function may impair male sperm function.
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Affiliation(s)
- Ida Marie Boisen
- Group of Skeletal, Mineral, and Gonadal Endocrinology, Department of Growth and Reproduction, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark
- Division of Bone and Mineral Research, Harvard School of Dental Medicine/Harvard Medical School, Harvard University, Boston, MA, USA
| | - Anders Rehfeld
- Department of Growth and Reproduction, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark
| | - Iris Mos
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Nadia Nicholine Poulsen
- Group of Skeletal, Mineral, and Gonadal Endocrinology, Department of Growth and Reproduction, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark
| | - John Erik Nielsen
- Department of Growth and Reproduction, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark
| | - Peter Schwarz
- Department of Endocrinology, Rigshospitalet, Copenhagen, Denmark
- Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Lars Rejnmark
- Department of Endocrinology, Aarhus University Hospital, Aarhus, Denmark
| | - Steen Dissing
- Department of Cellular and Molecular Medicine, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | | | - Anders Juul
- Department of Growth and Reproduction, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark
- Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Hans Bräuner-Osborne
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Beate Lanske
- Division of Bone and Mineral Research, Harvard School of Dental Medicine/Harvard Medical School, Harvard University, Boston, MA, USA
| | - Martin Blomberg Jensen
- Group of Skeletal, Mineral, and Gonadal Endocrinology, Department of Growth and Reproduction, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark
- Division of Bone and Mineral Research, Harvard School of Dental Medicine/Harvard Medical School, Harvard University, Boston, MA, USA
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21
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Hannan FM, Stevenson M, Bayliss AL, Stokes VJ, Stewart M, Kooblall KG, Gorvin CM, Codner G, Teboul L, Wells S, Thakker RV. Ap2s1 mutation causes hypercalcaemia in mice and impairs interaction between calcium-sensing receptor and adaptor protein-2. Hum Mol Genet 2021; 30:880-892. [PMID: 33729479 PMCID: PMC8165646 DOI: 10.1093/hmg/ddab076] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2020] [Revised: 02/09/2021] [Accepted: 02/26/2021] [Indexed: 12/16/2022] Open
Abstract
Adaptor protein 2 (AP2), a heterotetrameric complex comprising AP2α, AP2β2, AP2μ2 and AP2σ2 subunits, is ubiquitously expressed and involved in endocytosis and trafficking of membrane proteins, such as the calcium-sensing receptor (CaSR), a G-protein coupled receptor that signals via Gα11. Mutations of CaSR, Gα11 and AP2σ2, encoded by AP2S1, cause familial hypocalciuric hypercalcaemia types 1–3 (FHH1–3), respectively. FHH3 patients have heterozygous AP2S1 missense Arg15 mutations (p.Arg15Cys, p.Arg15His or p.Arg15Leu) with hypercalcaemia, which may be marked and symptomatic, and occasional hypophosphataemia and osteomalacia. To further characterize the phenotypic spectrum and calcitropic pathophysiology of FHH3, we used CRISPR/Cas9 genome editing to generate mice harboring the AP2S1 p.Arg15Leu mutation, which causes the most severe FHH3 phenotype. Heterozygous (Ap2s1+/L15) mice were viable, and had marked hypercalcaemia, hypermagnesaemia, hypophosphataemia, and increases in alkaline phosphatase activity and fibroblast growth factor-23. Plasma 1,25-dihydroxyvitamin D was normal, and no alterations in bone mineral density or bone turnover were noted. Homozygous (Ap2s1L15/L15) mice invariably died perinatally. Co-immunoprecipitation studies showed that the AP2S1 p.Arg15Leu mutation impaired protein–protein interactions between AP2σ2 and the other AP2 subunits, and also with the CaSR. Cinacalcet, a CaSR positive allosteric modulator, decreased plasma calcium and parathyroid hormone concentrations in Ap2s1+/L15 mice, but had no effect on the diminished AP2σ2-CaSR interaction in vitro. Thus, our studies have established a mouse model that is representative for FHH3 in humans, and demonstrated that the AP2S1 p.Arg15Leu mutation causes a predominantly calcitropic phenotype, which can be ameliorated by treatment with cinacalcet.
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Affiliation(s)
- Fadil M Hannan
- Academic Endocrine Unit, Radcliffe Department of Medicine, University of Oxford, Oxford OX3 7LJ, UK.,Nuffield Department of Women's and Reproductive Health, University of Oxford, Oxford OX3 9DU, UK
| | - Mark Stevenson
- Academic Endocrine Unit, Radcliffe Department of Medicine, University of Oxford, Oxford OX3 7LJ, UK
| | - Asha L Bayliss
- Academic Endocrine Unit, Radcliffe Department of Medicine, University of Oxford, Oxford OX3 7LJ, UK
| | - Victoria J Stokes
- Academic Endocrine Unit, Radcliffe Department of Medicine, University of Oxford, Oxford OX3 7LJ, UK
| | - Michelle Stewart
- Mammalian Genetics Unit and Mary Lyon Centre, MRC Harwell Institute, Harwell Campus, Oxfordshire OX11 0RD, UK
| | - Kreepa G Kooblall
- Academic Endocrine Unit, Radcliffe Department of Medicine, University of Oxford, Oxford OX3 7LJ, UK
| | - Caroline M Gorvin
- Academic Endocrine Unit, Radcliffe Department of Medicine, University of Oxford, Oxford OX3 7LJ, UK
| | - Gemma Codner
- Mammalian Genetics Unit and Mary Lyon Centre, MRC Harwell Institute, Harwell Campus, Oxfordshire OX11 0RD, UK
| | - Lydia Teboul
- Mammalian Genetics Unit and Mary Lyon Centre, MRC Harwell Institute, Harwell Campus, Oxfordshire OX11 0RD, UK
| | - Sara Wells
- Mammalian Genetics Unit and Mary Lyon Centre, MRC Harwell Institute, Harwell Campus, Oxfordshire OX11 0RD, UK
| | - Rajesh V Thakker
- Academic Endocrine Unit, Radcliffe Department of Medicine, University of Oxford, Oxford OX3 7LJ, UK
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22
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Cho H, Lee J, Jang S, Lee J, Oh TI, Son Y, Lee E. CaSR-Mediated hBMSCs Activity Modulation: Additional Coupling Mechanism in Bone Remodeling Compartment. Int J Mol Sci 2020; 22:ijms22010325. [PMID: 33396907 PMCID: PMC7795180 DOI: 10.3390/ijms22010325] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2020] [Revised: 12/24/2020] [Accepted: 12/27/2020] [Indexed: 02/01/2023] Open
Abstract
Near the bone remodeling compartments (BRC), extracellular calcium concentration (Ca2+o) is locally elevated and bone marrow stromal cells (BMSCs) close to the BRC can be exposed to high calcium concentration. The calcium-sensing receptor (CaSR) is known to play a key role in maintaining extracellular calcium homeostasis by sensing fluctuations in the levels of extracellular calcium (Ca2+o). When human BMSCs (hBMSCs) were exposed to various calcium concentrations (1.8, 3, 5, 10, 30 mM), moderate-high extracellular calcium concentrations (3–5 mM) stimulated proliferation, while a high calcium concentration (30 mM) inhibited the proliferation. Exposure to various calcium concentrations did not induce significant differences in the apoptotic cell fraction. Evaluation of multi-lineage differentiation potential showed no significant difference among various calcium concentration groups, except for the high calcium concentration (30 mM) treated group, which resulted in increased calcification after in vitro osteogenic differentiation. Treatment of NPS2143, a CaSR inhibitor, abolished the stimulatory effect on hBMSCs proliferation and migration indicating that CaSR is involved. These results suggest that the calcium concentration gradient near the BRC may play an important role in bone remodeling by acting as an osteoblast–osteoclast coupling mechanism through CaSR.
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Affiliation(s)
- Hyunji Cho
- College of Life Science and Graduate School of Biotechnology, Kyung Hee University, Seochon-dong, Kiheung-go, Yongin-si, Geonggi-do 17104, Korea;
| | - Jisoo Lee
- Department of Medical Engineering, Graduate School, Kyung Hee University, Seoul 02447, Korea; (J.L.); (S.J.)
| | - Seoyoung Jang
- Department of Medical Engineering, Graduate School, Kyung Hee University, Seoul 02447, Korea; (J.L.); (S.J.)
| | - Jungsun Lee
- R&D Institute, Biosolution Inc., Seoul 18111, Korea;
| | - Tong In Oh
- Department of Biomedical Engineering, School of Medicine, Kyung Hee University, Seoul 02447, Korea;
| | - Youngsook Son
- Department of Genetic Engineering, College of Life Science, Kyung Hee University, Seochon-dong, Kiheung-go, Yongin-si, Geonggi-do 17104, Korea
- Correspondence: (Y.S.); (E.L.); Tel.: +82-31-201-3822 (Y.S.); +82-10-3751-7532 (E.L.)
| | - EunAh Lee
- Impedance Imaging Research Center, Kyung Hee University, Seoul 02447, Korea
- Correspondence: (Y.S.); (E.L.); Tel.: +82-31-201-3822 (Y.S.); +82-10-3751-7532 (E.L.)
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23
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Schöneberg T, Liebscher I. Mutations in G Protein-Coupled Receptors: Mechanisms, Pathophysiology and Potential Therapeutic Approaches. Pharmacol Rev 2020; 73:89-119. [PMID: 33219147 DOI: 10.1124/pharmrev.120.000011] [Citation(s) in RCA: 51] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
There are approximately 800 annotated G protein-coupled receptor (GPCR) genes, making these membrane receptors members of the most abundant gene family in the human genome. Besides being involved in manifold physiologic functions and serving as important pharmacotherapeutic targets, mutations in 55 GPCR genes cause about 66 inherited monogenic diseases in humans. Alterations of nine GPCR genes are causatively involved in inherited digenic diseases. In addition to classic gain- and loss-of-function variants, other aspects, such as biased signaling, trans-signaling, ectopic expression, allele variants of GPCRs, pseudogenes, gene fusion, and gene dosage, contribute to the repertoire of GPCR dysfunctions. However, the spectrum of alterations and GPCR involvement is probably much larger because an additional 91 GPCR genes contain homozygous or hemizygous loss-of-function mutations in human individuals with currently unidentified phenotypes. This review highlights the complexity of genomic alteration of GPCR genes as well as their functional consequences and discusses derived therapeutic approaches. SIGNIFICANCE STATEMENT: With the advent of new transgenic and sequencing technologies, the number of monogenic diseases related to G protein-coupled receptor (GPCR) mutants has significantly increased, and our understanding of the functional impact of certain kinds of mutations has substantially improved. Besides the classical gain- and loss-of-function alterations, additional aspects, such as biased signaling, trans-signaling, ectopic expression, allele variants of GPCRs, uniparental disomy, pseudogenes, gene fusion, and gene dosage, need to be elaborated in light of GPCR dysfunctions and possible therapeutic strategies.
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Affiliation(s)
- Torsten Schöneberg
- Rudolf Schönheimer Institute of Biochemistry, Molecular Biochemistry, Medical Faculty, Leipzig, Germany
| | - Ines Liebscher
- Rudolf Schönheimer Institute of Biochemistry, Molecular Biochemistry, Medical Faculty, Leipzig, Germany
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24
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Mouly C, Vargas-Poussou R, Lienhardt A, Silve C, Hureaux M, Magdelaine C, Buffet A, Grunenwald S, Kuhn JM, Brue T, Reznik Y, Tabarin A, Martin-Coignard D, Haymann JP, Tack I, Bennet A, Caron P, Linglart A, Vezzosi D. Clinical characteristics of familial hypocalciuric hypercalcaemia type 1: A multicentre study of 77 adult patients. Clin Endocrinol (Oxf) 2020; 93:248-260. [PMID: 32347971 DOI: 10.1111/cen.14211] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/16/2019] [Revised: 03/17/2020] [Accepted: 03/31/2020] [Indexed: 11/30/2022]
Abstract
OBJECTIVE Familial hypocalciuric hypercalcaemia type 1 (FHH1), related to heterozygous loss-of-function mutations of the calcium-sensing receptor gene, is the main differential diagnosis for primary hyperparathyroidism. The aim of our study was to describe clinical characteristics of adult patients living in France with a genetically confirmed FHH1. DESIGN AND PATIENTS This observational, retrospective, multicentre study included 77 adults, followed up in 32 clinical departments in France, with a genetic FHH1 diagnosis between 2001 and 2012. RESULTS Hypercalcaemia was diagnosed at a median age of 53 years [IQR: 38-61]. The diagnosis was made after clinical manifestations, routine analysis or familial screening in 56, 34 and 10% of cases, respectively, (n = 58; data not available for 19 patients). Chondrocalcinosis was present in 11/51 patients (22%), bone fractures in 8/56 (14%) and renal colic in 6/55 (11%). The median serum calcium was 2.74 mmol/L [IQR: 2.63-2.86 mmol/L], the median plasma parathyroid hormone level was 4.9 pmol/L [3.1-7.1], and the median 24-hour urinary calcium excretion was 2.8 mmol/24 hours [IQR: 1.9-4.0]. Osteoporosis (dual X-ray absorptiometry) or kidney stones (renal ultrasonography) were found in 6/38 patients (16%) and 9/32 patients (28%), respectively. Fourteen patients (18%) underwent parathyroid surgery; parathyroid adenoma was found in three patients (21%) and parathyroid hyperplasia in nine patients (64%). No correlation between genotype and phenotype was established. CONCLUSION This large cohort study demonstrates that FHH1 clinical characteristics can be atypical in 33 patients (43%). Clinicians should be aware of this rare differential diagnosis in order to adopt an appropriate treatment strategy.
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Affiliation(s)
- Céline Mouly
- Department of Endocrinology, Larrey Hospital, CardioMet Institute, University Hospital Centre of Toulouse, Toulouse, France
| | | | - Anne Lienhardt
- Department of Medical Paediatrics, University Hospital Centre of Limoges, Limoges, France
| | - Caroline Silve
- Department of Molecular Biochemistry and Genetics, Cochin Hospital, Paris, France
| | - Marguerite Hureaux
- Department of Genetics, European Hospital Georges Pompidou, Paris, France
| | - Corinne Magdelaine
- Department of Molecular Genetic Biochemistry, University Hospital Centre of Limoges, Limoges, France
| | - Alexandre Buffet
- Department of Endocrinology, Larrey Hospital, CardioMet Institute, University Hospital Centre of Toulouse, Toulouse, France
| | - Solange Grunenwald
- Department of Endocrinology, Larrey Hospital, CardioMet Institute, University Hospital Centre of Toulouse, Toulouse, France
| | - Jean-Marc Kuhn
- Department of Endocrinology, Diabetes and Metabolic Diseases, University Hospital Centre of Rouen, Rouen, France
| | - Thierry Brue
- Department of Endocrinology, Diabetes and Metabolic Disorders, University Hospital Centre of Marseille, Marseille, France
| | - Yves Reznik
- Department of Endocrinology-Diabetology, University Hospital Centre of Caen, Caen, France
| | - Antoine Tabarin
- Department of Endocrinology, Diabetology, Metabolic Diseases and Nutrition, University Hospital Centre of Bordeaux, Bordeaux, France
| | | | | | - Ivan Tack
- Department of Physiological Function Tests, University Hospital Centre of Toulouse, Toulouse, France
| | - Antoine Bennet
- Department of Endocrinology, Larrey Hospital, CardioMet Institute, University Hospital Centre of Toulouse, Toulouse, France
| | - Philippe Caron
- Department of Endocrinology, Larrey Hospital, CardioMet Institute, University Hospital Centre of Toulouse, Toulouse, France
| | - Agnès Linglart
- Department of Paediatric Endocrinology, Diabetology and Severe Obesity, Bicêtre Hospital, Paris, France
| | - Delphine Vezzosi
- Department of Endocrinology, Larrey Hospital, CardioMet Institute, University Hospital Centre of Toulouse, Toulouse, France
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25
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Magno AL, Leatherbarrow KM, Brown SJ, Wilson SG, Walsh JP, Ward BK. Functional Analysis of Calcium-Sensing Receptor Variants Identified in Families Provisionally Diagnosed with Familial Hypocalciuric Hypercalcaemia. Calcif Tissue Int 2020; 107:230-239. [PMID: 32638038 DOI: 10.1007/s00223-020-00715-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/08/2020] [Accepted: 06/18/2020] [Indexed: 12/11/2022]
Abstract
Identification of variants in the calcium-sensing receptor (CASR) gene is an important means of distinguishing between familial hypocalciuric hypercalcaemia (FHH) and primary hyperparathyroidism. However, identification and bioinformatics analysis of genetic variants alone is now considered insufficient as definitive proof; additional functional assessment is required to diagnose FHH with certainty. We identified two novel variants, D433Y and C739Y, and one previously reported variant G509R in the CASR of four kindreds provisionally diagnosed with FHH and aimed to functionally characterise these variants to confirm the diagnosis. Variant receptors were cloned as FLAG-tagged constructs into the mammalian expression vector, pcDNA3.1. Wild type and variant receptor constructs were expressed in HEK293 cells and their expression assessed by Western blot analysis and their functionality analysed using an IP-One assay which measures myo-inositol 1-phosphate accumulation following CaSR activation. Western blot analysis showed that the D433Y receptor had diminished mature glycosylated receptor compared with wild type CaSR whereas the G509R receptor had a complete lack of mature receptor. The C739Y receptor was consistently overexpressed. Functional assessment showed the D433Y receptor to be mildly inactivating at physiological calcium concentrations whereas the G509R receptor was inactive at all calcium concentrations. By contrast, the C739Y variant was activating compared to wild type receptor which is inconsistent with it causing FHH. We conclude that functional assessment of CaSR variants using the IP-One assay was useful in the investigation of suspected FHH probands, confirming the D433Y and G509R variants as likely pathogenic/pathogenic, but dismissing the C739Y variant as causing FHH.
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Affiliation(s)
- Aaron L Magno
- Department of Endocrinology and Diabetes, Sir Charles Gairdner Hospital, Block C, Level 1, Hospital Avenue, Nedlands, WA, Australia
| | - Kassandra M Leatherbarrow
- Department of Endocrinology and Diabetes, Sir Charles Gairdner Hospital, Block C, Level 1, Hospital Avenue, Nedlands, WA, Australia
| | - Suzanne J Brown
- Department of Endocrinology and Diabetes, Sir Charles Gairdner Hospital, Block C, Level 1, Hospital Avenue, Nedlands, WA, Australia
| | - Scott G Wilson
- Department of Endocrinology and Diabetes, Sir Charles Gairdner Hospital, Block C, Level 1, Hospital Avenue, Nedlands, WA, Australia
- School of Biomedical Sciences, University of Western Australia, Nedlands, WA, Australia
- Department of Twin Research and Genetic Epidemiology, King's College London, London, UK
| | - John P Walsh
- Department of Endocrinology and Diabetes, Sir Charles Gairdner Hospital, Block C, Level 1, Hospital Avenue, Nedlands, WA, Australia
- Medical School, University of Western Australia, Nedlands, WA, Australia
| | - Bryan K Ward
- Department of Endocrinology and Diabetes, Sir Charles Gairdner Hospital, Block C, Level 1, Hospital Avenue, Nedlands, WA, Australia.
- Harry Perkins Institute of Medical Research, Centre for Medical Research, QEII Medical Centre, University of Western Australia, Nedlands, WA, Australia.
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Calcium-Sensing Receptor and Regulation of WNK Kinases in the Kidney. Cells 2020; 9:cells9071644. [PMID: 32659887 PMCID: PMC7407487 DOI: 10.3390/cells9071644] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2020] [Revised: 07/01/2020] [Accepted: 07/06/2020] [Indexed: 12/27/2022] Open
Abstract
The kidney is essential for systemic calcium homeostasis. Urinary calcium excretion can be viewed as an integrative renal response to endocrine and local stimuli. The extracellular calcium-sensing receptor (CaSR) elicits a number of adaptive reactions to increased plasma Ca2+ levels including the control of parathyroid hormone release and regulation of the renal calcium handling. Calcium reabsorption in the distal nephron of the kidney is functionally coupled to sodium transport. Apart from Ca2+ transport systems, CaSR signaling affects relevant distal Na+-(K+)-2Cl- cotransporters, NKCC2 and NCC. NKCC2 and NCC are activated by a kinase cascade comprising with-no-lysine [K] kinases (WNKs) and two homologous Ste20-related kinases, SPAK and OSR1. Gain-of-function mutations within the WNK-SPAK/OSR1-NKCC2/NCC pathway lead to renal salt retention and hypertension, whereas loss-of-function mutations have been associated with salt-losing tubulopathies such as Bartter or Gitelman syndromes. A Bartter-like syndrome has been also described in patients carrying gain-of-function mutations in the CaSR gene. Recent work suggested that CaSR signals via the WNK-SPAK/OSR1 cascade to modulate salt reabsorption along the distal nephron. The review presented here summarizes the latest progress in understanding of functional interactions between CaSR and WNKs and their potential impact on the renal salt handling and blood pressure.
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27
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Leach K, Hannan FM, Josephs TM, Keller AN, Møller TC, Ward DT, Kallay E, Mason RS, Thakker RV, Riccardi D, Conigrave AD, Bräuner-Osborne H. International Union of Basic and Clinical Pharmacology. CVIII. Calcium-Sensing Receptor Nomenclature, Pharmacology, and Function. Pharmacol Rev 2020; 72:558-604. [PMID: 32467152 PMCID: PMC7116503 DOI: 10.1124/pr.119.018531] [Citation(s) in RCA: 47] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
The calcium-sensing receptor (CaSR) is a class C G protein-coupled receptor that responds to multiple endogenous agonists and allosteric modulators, including divalent and trivalent cations, L-amino acids, γ-glutamyl peptides, polyamines, polycationic peptides, and protons. The CaSR plays a critical role in extracellular calcium (Ca2+ o) homeostasis, as demonstrated by the many naturally occurring mutations in the CaSR or its signaling partners that cause Ca2+ o homeostasis disorders. However, CaSR tissue expression in mammals is broad and includes tissues unrelated to Ca2+ o homeostasis, in which it, for example, regulates the secretion of digestive hormones, airway constriction, cardiovascular effects, cellular differentiation, and proliferation. Thus, although the CaSR is targeted clinically by the positive allosteric modulators (PAMs) cinacalcet, evocalcet, and etelcalcetide in hyperparathyroidism, it is also a putative therapeutic target in diabetes, asthma, cardiovascular disease, and cancer. The CaSR is somewhat unique in possessing multiple ligand binding sites, including at least five putative sites for the "orthosteric" agonist Ca2+ o, an allosteric site for endogenous L-amino acids, two further allosteric sites for small molecules and the peptide PAM, etelcalcetide, and additional sites for other cations and anions. The CaSR is promiscuous in its G protein-coupling preferences, and signals via Gq/11, Gi/o, potentially G12/13, and even Gs in some cell types. Not surprisingly, the CaSR is subject to biased agonism, in which distinct ligands preferentially stimulate a subset of the CaSR's possible signaling responses, to the exclusion of others. The CaSR thus serves as a model receptor to study natural bias and allostery. SIGNIFICANCE STATEMENT: The calcium-sensing receptor (CaSR) is a complex G protein-coupled receptor that possesses multiple orthosteric and allosteric binding sites, is subject to biased signaling via several different G proteins, and has numerous (patho)physiological roles. Understanding the complexities of CaSR structure, function, and biology will aid future drug discovery efforts seeking to target this receptor for a diversity of diseases. This review summarizes what is known to date regarding key structural, pharmacological, and physiological features of the CaSR.
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Affiliation(s)
- Katie Leach
- Drug Discovery Biology, Monash Institute of Pharmaceutical Science, Monash University, Parkville, Australia (K.L., T.M.J., A.N.K.); Nuffield Department of Women's & Reproductive Health (F.M.H.) and Academic Endocrine Unit, Radcliffe Department of Clinical Medicine (F.M.H., R.V.T.), University of Oxford, Oxford, United Kingdom; Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark (T.C.M., H.B.-O.); Faculty of Biology, Medicine and Health, The University of Manchester, Manchester, United Kingdom (D.T.W.); Department of Pathophysiology and Allergy Research, Medical University of Vienna, Vienna, Austria (E.K.); Physiology, School of Medical Sciences and Bosch Institute (R.S.M.) and School of Life & Environmental Sciences, Charles Perkins Centre (A.D.C.), University of Sydney, Sydney, Australia; and School of Biosciences, Cardiff University, Cardiff, United Kingdom (D.R.)
| | - Fadil M Hannan
- Drug Discovery Biology, Monash Institute of Pharmaceutical Science, Monash University, Parkville, Australia (K.L., T.M.J., A.N.K.); Nuffield Department of Women's & Reproductive Health (F.M.H.) and Academic Endocrine Unit, Radcliffe Department of Clinical Medicine (F.M.H., R.V.T.), University of Oxford, Oxford, United Kingdom; Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark (T.C.M., H.B.-O.); Faculty of Biology, Medicine and Health, The University of Manchester, Manchester, United Kingdom (D.T.W.); Department of Pathophysiology and Allergy Research, Medical University of Vienna, Vienna, Austria (E.K.); Physiology, School of Medical Sciences and Bosch Institute (R.S.M.) and School of Life & Environmental Sciences, Charles Perkins Centre (A.D.C.), University of Sydney, Sydney, Australia; and School of Biosciences, Cardiff University, Cardiff, United Kingdom (D.R.)
| | - Tracy M Josephs
- Drug Discovery Biology, Monash Institute of Pharmaceutical Science, Monash University, Parkville, Australia (K.L., T.M.J., A.N.K.); Nuffield Department of Women's & Reproductive Health (F.M.H.) and Academic Endocrine Unit, Radcliffe Department of Clinical Medicine (F.M.H., R.V.T.), University of Oxford, Oxford, United Kingdom; Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark (T.C.M., H.B.-O.); Faculty of Biology, Medicine and Health, The University of Manchester, Manchester, United Kingdom (D.T.W.); Department of Pathophysiology and Allergy Research, Medical University of Vienna, Vienna, Austria (E.K.); Physiology, School of Medical Sciences and Bosch Institute (R.S.M.) and School of Life & Environmental Sciences, Charles Perkins Centre (A.D.C.), University of Sydney, Sydney, Australia; and School of Biosciences, Cardiff University, Cardiff, United Kingdom (D.R.)
| | - Andrew N Keller
- Drug Discovery Biology, Monash Institute of Pharmaceutical Science, Monash University, Parkville, Australia (K.L., T.M.J., A.N.K.); Nuffield Department of Women's & Reproductive Health (F.M.H.) and Academic Endocrine Unit, Radcliffe Department of Clinical Medicine (F.M.H., R.V.T.), University of Oxford, Oxford, United Kingdom; Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark (T.C.M., H.B.-O.); Faculty of Biology, Medicine and Health, The University of Manchester, Manchester, United Kingdom (D.T.W.); Department of Pathophysiology and Allergy Research, Medical University of Vienna, Vienna, Austria (E.K.); Physiology, School of Medical Sciences and Bosch Institute (R.S.M.) and School of Life & Environmental Sciences, Charles Perkins Centre (A.D.C.), University of Sydney, Sydney, Australia; and School of Biosciences, Cardiff University, Cardiff, United Kingdom (D.R.)
| | - Thor C Møller
- Drug Discovery Biology, Monash Institute of Pharmaceutical Science, Monash University, Parkville, Australia (K.L., T.M.J., A.N.K.); Nuffield Department of Women's & Reproductive Health (F.M.H.) and Academic Endocrine Unit, Radcliffe Department of Clinical Medicine (F.M.H., R.V.T.), University of Oxford, Oxford, United Kingdom; Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark (T.C.M., H.B.-O.); Faculty of Biology, Medicine and Health, The University of Manchester, Manchester, United Kingdom (D.T.W.); Department of Pathophysiology and Allergy Research, Medical University of Vienna, Vienna, Austria (E.K.); Physiology, School of Medical Sciences and Bosch Institute (R.S.M.) and School of Life & Environmental Sciences, Charles Perkins Centre (A.D.C.), University of Sydney, Sydney, Australia; and School of Biosciences, Cardiff University, Cardiff, United Kingdom (D.R.)
| | - Donald T Ward
- Drug Discovery Biology, Monash Institute of Pharmaceutical Science, Monash University, Parkville, Australia (K.L., T.M.J., A.N.K.); Nuffield Department of Women's & Reproductive Health (F.M.H.) and Academic Endocrine Unit, Radcliffe Department of Clinical Medicine (F.M.H., R.V.T.), University of Oxford, Oxford, United Kingdom; Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark (T.C.M., H.B.-O.); Faculty of Biology, Medicine and Health, The University of Manchester, Manchester, United Kingdom (D.T.W.); Department of Pathophysiology and Allergy Research, Medical University of Vienna, Vienna, Austria (E.K.); Physiology, School of Medical Sciences and Bosch Institute (R.S.M.) and School of Life & Environmental Sciences, Charles Perkins Centre (A.D.C.), University of Sydney, Sydney, Australia; and School of Biosciences, Cardiff University, Cardiff, United Kingdom (D.R.)
| | - Enikö Kallay
- Drug Discovery Biology, Monash Institute of Pharmaceutical Science, Monash University, Parkville, Australia (K.L., T.M.J., A.N.K.); Nuffield Department of Women's & Reproductive Health (F.M.H.) and Academic Endocrine Unit, Radcliffe Department of Clinical Medicine (F.M.H., R.V.T.), University of Oxford, Oxford, United Kingdom; Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark (T.C.M., H.B.-O.); Faculty of Biology, Medicine and Health, The University of Manchester, Manchester, United Kingdom (D.T.W.); Department of Pathophysiology and Allergy Research, Medical University of Vienna, Vienna, Austria (E.K.); Physiology, School of Medical Sciences and Bosch Institute (R.S.M.) and School of Life & Environmental Sciences, Charles Perkins Centre (A.D.C.), University of Sydney, Sydney, Australia; and School of Biosciences, Cardiff University, Cardiff, United Kingdom (D.R.)
| | - Rebecca S Mason
- Drug Discovery Biology, Monash Institute of Pharmaceutical Science, Monash University, Parkville, Australia (K.L., T.M.J., A.N.K.); Nuffield Department of Women's & Reproductive Health (F.M.H.) and Academic Endocrine Unit, Radcliffe Department of Clinical Medicine (F.M.H., R.V.T.), University of Oxford, Oxford, United Kingdom; Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark (T.C.M., H.B.-O.); Faculty of Biology, Medicine and Health, The University of Manchester, Manchester, United Kingdom (D.T.W.); Department of Pathophysiology and Allergy Research, Medical University of Vienna, Vienna, Austria (E.K.); Physiology, School of Medical Sciences and Bosch Institute (R.S.M.) and School of Life & Environmental Sciences, Charles Perkins Centre (A.D.C.), University of Sydney, Sydney, Australia; and School of Biosciences, Cardiff University, Cardiff, United Kingdom (D.R.)
| | - Rajesh V Thakker
- Drug Discovery Biology, Monash Institute of Pharmaceutical Science, Monash University, Parkville, Australia (K.L., T.M.J., A.N.K.); Nuffield Department of Women's & Reproductive Health (F.M.H.) and Academic Endocrine Unit, Radcliffe Department of Clinical Medicine (F.M.H., R.V.T.), University of Oxford, Oxford, United Kingdom; Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark (T.C.M., H.B.-O.); Faculty of Biology, Medicine and Health, The University of Manchester, Manchester, United Kingdom (D.T.W.); Department of Pathophysiology and Allergy Research, Medical University of Vienna, Vienna, Austria (E.K.); Physiology, School of Medical Sciences and Bosch Institute (R.S.M.) and School of Life & Environmental Sciences, Charles Perkins Centre (A.D.C.), University of Sydney, Sydney, Australia; and School of Biosciences, Cardiff University, Cardiff, United Kingdom (D.R.)
| | - Daniela Riccardi
- Drug Discovery Biology, Monash Institute of Pharmaceutical Science, Monash University, Parkville, Australia (K.L., T.M.J., A.N.K.); Nuffield Department of Women's & Reproductive Health (F.M.H.) and Academic Endocrine Unit, Radcliffe Department of Clinical Medicine (F.M.H., R.V.T.), University of Oxford, Oxford, United Kingdom; Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark (T.C.M., H.B.-O.); Faculty of Biology, Medicine and Health, The University of Manchester, Manchester, United Kingdom (D.T.W.); Department of Pathophysiology and Allergy Research, Medical University of Vienna, Vienna, Austria (E.K.); Physiology, School of Medical Sciences and Bosch Institute (R.S.M.) and School of Life & Environmental Sciences, Charles Perkins Centre (A.D.C.), University of Sydney, Sydney, Australia; and School of Biosciences, Cardiff University, Cardiff, United Kingdom (D.R.)
| | - Arthur D Conigrave
- Drug Discovery Biology, Monash Institute of Pharmaceutical Science, Monash University, Parkville, Australia (K.L., T.M.J., A.N.K.); Nuffield Department of Women's & Reproductive Health (F.M.H.) and Academic Endocrine Unit, Radcliffe Department of Clinical Medicine (F.M.H., R.V.T.), University of Oxford, Oxford, United Kingdom; Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark (T.C.M., H.B.-O.); Faculty of Biology, Medicine and Health, The University of Manchester, Manchester, United Kingdom (D.T.W.); Department of Pathophysiology and Allergy Research, Medical University of Vienna, Vienna, Austria (E.K.); Physiology, School of Medical Sciences and Bosch Institute (R.S.M.) and School of Life & Environmental Sciences, Charles Perkins Centre (A.D.C.), University of Sydney, Sydney, Australia; and School of Biosciences, Cardiff University, Cardiff, United Kingdom (D.R.)
| | - Hans Bräuner-Osborne
- Drug Discovery Biology, Monash Institute of Pharmaceutical Science, Monash University, Parkville, Australia (K.L., T.M.J., A.N.K.); Nuffield Department of Women's & Reproductive Health (F.M.H.) and Academic Endocrine Unit, Radcliffe Department of Clinical Medicine (F.M.H., R.V.T.), University of Oxford, Oxford, United Kingdom; Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark (T.C.M., H.B.-O.); Faculty of Biology, Medicine and Health, The University of Manchester, Manchester, United Kingdom (D.T.W.); Department of Pathophysiology and Allergy Research, Medical University of Vienna, Vienna, Austria (E.K.); Physiology, School of Medical Sciences and Bosch Institute (R.S.M.) and School of Life & Environmental Sciences, Charles Perkins Centre (A.D.C.), University of Sydney, Sydney, Australia; and School of Biosciences, Cardiff University, Cardiff, United Kingdom (D.R.)
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28
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Onopiuk M, Eby B, Nesin V, Ngo P, Lerner M, Gorvin CM, Stokes VJ, Thakker RV, Brandi ML, Chang W, Humphrey MB, Tsiokas L, Lau K. Control of PTH secretion by the TRPC1 ion channel. JCI Insight 2020; 5:132496. [PMID: 32213715 PMCID: PMC7205425 DOI: 10.1172/jci.insight.132496] [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: 08/08/2019] [Accepted: 03/16/2020] [Indexed: 11/17/2022] Open
Abstract
Familial hypocalciuric hypercalcemia (FHH) is a genetic condition associated with hypocalciuria, hypercalcemia, and, in some cases, inappropriately high levels of circulating parathyroid hormone (PTH). FHH is associated with inactivating mutations in the gene encoding the Ca2+-sensing receptor (CaSR), a GPCR, and GNA11 encoding G protein subunit α 11 (Gα11), implicating defective GPCR signaling as the root pathophysiology for FHH. However, the downstream mechanism by which CaSR activation inhibits PTH production/secretion is incompletely understood. Here, we show that mice lacking the transient receptor potential canonical channel 1 (TRPC1) develop chronic hypercalcemia, hypocalciuria, and elevated PTH levels, mimicking human FHH. Ex vivo and in vitro studies revealed that TRPC1 serves a necessary and sufficient mediator to suppress PTH secretion from parathyroid glands (PTGs) downstream of CaSR in response to high extracellular Ca2+ concentration. Gα11 physically interacted with both the N- and C-termini of TRPC1 and enhanced CaSR-induced TRPC1 activity in transfected cells. These data identify TRPC1-mediated Ca2+ signaling as an essential component of the cellular apparatus controlling PTH secretion in the PTG downstream of CaSR.
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Affiliation(s)
| | - Bonnie Eby
- Department of Medicine, Division of Nephrology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, USA
| | | | | | - Megan Lerner
- Department of Surgery, Oklahoma City, Oklahoma, USA
| | - Caroline M Gorvin
- Academic Endocrine Unit, Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - Victoria J Stokes
- Academic Endocrine Unit, Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - Rajesh V Thakker
- Academic Endocrine Unit, Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - Maria Luisa Brandi
- Department of Biomedicals Sperimentals and Clinicals Sciences, Università degli Studi di Firenze and Fondazione FIRMO, Florence, Italy
| | - Wenhan Chang
- Endocrinology and Metabolism, Department of Medicine, UCSF, San Francisco, California, USA
| | - Mary Beth Humphrey
- Department of Medicine, Division of Rheumatology, Immunology, and Allergy, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, USA.,Department of Veterans Affairs, Oklahoma City, Oklahoma, USA
| | | | - Kai Lau
- Department of Medicine, Division of Nephrology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, USA.,Department of Veterans Affairs, Oklahoma City, Oklahoma, USA
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29
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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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30
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Madhavan P, Van Do TH, Bale A, Majumdar S. A NOVEL MUTATION IN CALCIUM-SENSING RECEPTOR PRESENTING AS FAMILIAL HYPOCALCIURIC HYPERCALCEMIA IN A YOUNG MAN. AACE Clin Case Rep 2020; 5:e226-e229. [PMID: 31967040 DOI: 10.4158/accr-2018-0236] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2018] [Accepted: 01/20/2019] [Indexed: 12/28/2022] Open
Abstract
Objective Familial hypocalciuric hypercalcemia (FHH) is considered a relatively benign condition characterized by elevated serum calcium with relatively low urinary calcium excretion. It typically results from an altered set point in calcium homeostasis originating from mutations in the calcium-sensing receptor (CASR), AP2S1, or GNA11 genes, which encode for the calcium-sensing receptor (CaSR), adaptor-related protein complex 2, and G-protein alpha-11 subunit, respectively. Despite numerous reports of novel variants in these genes associated with FHH, new variants continue to be discovered. Methods We describe a 20-year-old man with a family history of hypercalcemia who had clinical findings compatible with FHH and no evidence of multiple endocrine neoplasia who underwent CASR gene sequencing for evaluation of hypercalcemia. Parathyroid gland single-photon emission computerized tomography scan was normal. Results CASR gene sequencing revealed a previously unreported heterozygous intronic variant at position 1608+3A>G (chromosome 3: 121994892) resulting in a 77-residue deletion. His mother has a history of bipolar disorder and hyperparathyroidism with an adenoma found on imaging, yet our patient had no evidence of adenoma and therefore no surgical intervention was recommended. Given that CaSR plays a role in parathyroid growth, some variants in CASR may ultimately lead to parathyroid hypertrophy and be mistaken for primary hyperparathyroidism. Conclusion Long-term clinical follow up will be helpful in understanding the ultimate effects of specific CASR mutations on parathyroid growth or progression to significant hypercalcemia.
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31
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van der Wijst J, Belge H, Bindels RJM, Devuyst O. Learning Physiology From Inherited Kidney Disorders. Physiol Rev 2019; 99:1575-1653. [PMID: 31215303 DOI: 10.1152/physrev.00008.2018] [Citation(s) in RCA: 52] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
The identification of genes causing inherited kidney diseases yielded crucial insights in the molecular basis of disease and improved our understanding of physiological processes that operate in the kidney. Monogenic kidney disorders are caused by mutations in genes coding for a large variety of proteins including receptors, channels and transporters, enzymes, transcription factors, and structural components, operating in specialized cell types that perform highly regulated homeostatic functions. Common variants in some of these genes are also associated with complex traits, as evidenced by genome-wide association studies in the general population. In this review, we discuss how the molecular genetics of inherited disorders affecting different tubular segments of the nephron improved our understanding of various transport processes and of their involvement in homeostasis, while providing novel therapeutic targets. These include inherited disorders causing a dysfunction of the proximal tubule (renal Fanconi syndrome), with emphasis on epithelial differentiation and receptor-mediated endocytosis, or affecting the reabsorption of glucose, the handling of uric acid, and the reabsorption of sodium, calcium, and magnesium along the kidney tubule.
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Affiliation(s)
- Jenny van der Wijst
- Department of Physiology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center , Nijmegen , The Netherlands ; Institute of Physiology, University of Zurich , Zurich , Switzerland ; and Division of Nephrology, Institute of Experimental and Clinical Research (IREC), Medical School, Université catholique de Louvain, Brussels, Belgium
| | - Hendrica Belge
- Department of Physiology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center , Nijmegen , The Netherlands ; Institute of Physiology, University of Zurich , Zurich , Switzerland ; and Division of Nephrology, Institute of Experimental and Clinical Research (IREC), Medical School, Université catholique de Louvain, Brussels, Belgium
| | - René J M Bindels
- Department of Physiology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center , Nijmegen , The Netherlands ; Institute of Physiology, University of Zurich , Zurich , Switzerland ; and Division of Nephrology, Institute of Experimental and Clinical Research (IREC), Medical School, Université catholique de Louvain, Brussels, Belgium
| | - Olivier Devuyst
- Department of Physiology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center , Nijmegen , The Netherlands ; Institute of Physiology, University of Zurich , Zurich , Switzerland ; and Division of Nephrology, Institute of Experimental and Clinical Research (IREC), Medical School, Université catholique de Louvain, Brussels, Belgium
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32
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The Nervous System Relevance of the Calcium Sensing Receptor in Health and Disease. Molecules 2019; 24:molecules24142546. [PMID: 31336912 PMCID: PMC6680999 DOI: 10.3390/molecules24142546] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2019] [Revised: 07/05/2019] [Accepted: 07/10/2019] [Indexed: 02/08/2023] Open
Abstract
The calcium sensing receptor (CaSR) was first identified in parathyroid glands, and its primary role in controlling systemic calcium homeostasis by the regulation of parathyroid hormone (PTH) secretion has been extensively described in literature. Additionally, the receptor has also been investigated in cells and tissues not directly involved in calcium homeostasis, e.g., the nervous system (NS), where it plays crucial roles in early neural development for the differentiation of neurons and glial cells, as well as in the adult nervous system for synaptic transmission and plasticity. Advances in the knowledge of the CaSR's function in such physiological processes have encouraged researchers to further broaden the receptor's investigation in the neuro-pathological conditions of the NS. Interestingly, pre-clinical data suggest that receptor inhibition by calcilytics might be effective in counteracting the pathomechanism underlying Alzheimer's disease and ischemia, while a CaSR positive modulation with calcimimetics has been proposed as a potential approach for treating neuroblastoma. Importantly, such promising findings led to the repurposing of CaSR modulators as novel pharmacological alternatives for these disorders. Therefore, the aim of this review article is to critically appraise evidence which, so far, has been yielded from the investigation of the role of the CaSR in physiology of the nervous system and to focus on the most recent emerging concepts which have reported the receptor as a therapeutic target for neurodegeneration and neuroblastic tumors.
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33
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The role of GPCRs in bone diseases and dysfunctions. Bone Res 2019; 7:19. [PMID: 31646011 PMCID: PMC6804689 DOI: 10.1038/s41413-019-0059-6] [Citation(s) in RCA: 52] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2019] [Revised: 05/22/2019] [Accepted: 05/27/2019] [Indexed: 12/13/2022] Open
Abstract
The superfamily of G protein-coupled receptors (GPCRs) contains immense structural and functional diversity and mediates a myriad of biological processes upon activation by various extracellular signals. Critical roles of GPCRs have been established in bone development, remodeling, and disease. Multiple human GPCR mutations impair bone development or metabolism, resulting in osteopathologies. Here we summarize the disease phenotypes and dysfunctions caused by GPCR gene mutations in humans as well as by deletion in animals. To date, 92 receptors (5 glutamate family, 67 rhodopsin family, 5 adhesion, 4 frizzled/taste2 family, 5 secretin family, and 6 other 7TM receptors) have been associated with bone diseases and dysfunctions (36 in humans and 72 in animals). By analyzing data from these 92 GPCRs, we found that mutation or deletion of different individual GPCRs could induce similar bone diseases or dysfunctions, and the same individual GPCR mutation or deletion could induce different bone diseases or dysfunctions in different populations or animal models. Data from human diseases or dysfunctions identified 19 genes whose mutation was associated with human BMD: 9 genes each for human height and osteoporosis; 4 genes each for human osteoarthritis (OA) and fracture risk; and 2 genes each for adolescent idiopathic scoliosis (AIS), periodontitis, osteosarcoma growth, and tooth development. Reports from gene knockout animals found 40 GPCRs whose deficiency reduced bone mass, while deficiency of 22 GPCRs increased bone mass and BMD; deficiency of 8 GPCRs reduced body length, while 5 mice had reduced femur size upon GPCR deletion. Furthermore, deficiency in 6 GPCRs induced osteoporosis; 4 induced osteoarthritis; 3 delayed fracture healing; 3 reduced arthritis severity; and reduced bone strength, increased bone strength, and increased cortical thickness were each observed in 2 GPCR-deficiency models. The ever-expanding number of GPCR mutation-associated diseases warrants accelerated molecular analysis, population studies, and investigation of phenotype correlation with SNPs to elucidate GPCR function in human diseases.
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34
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Balenga N, Koh J, Azimzadeh P, Hogue J, Gabr M, Stains JP, Olson JA. Parathyroid-Targeted Overexpression of Regulator of G-Protein Signaling 5 (RGS5) Causes Hyperparathyroidism in Transgenic Mice. J Bone Miner Res 2019; 34:955-963. [PMID: 30690792 PMCID: PMC8210536 DOI: 10.1002/jbmr.3674] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/31/2018] [Revised: 12/14/2018] [Accepted: 12/18/2018] [Indexed: 12/20/2022]
Abstract
The relationship between impaired calcium sensing, dysregulated parathyroid hormone (PTH) secretion, and parathyroid cell proliferation in parathyroid neoplasia is not understood. We previously reported that a GTPase activating protein, regulator of G-protein signaling 5 (RGS5) is overexpressed in a subset of parathyroid tumors associated with primary hyperparathyroidism (PHPT) and that RGS5 can inhibit signaling from the calcium-sensing receptor (CASR). In vivo, we found that RGS5-null mice have abnormally low PTH levels. To gain a better understanding of the potential role of RGS5 overexpression in parathyroid neoplasia and PHPT and to investigate whether inhibition of CASR signaling can lead to parathyroid neoplasia, we created and characterized a transgenic mouse strain overexpressing RGS5 specifically in the parathyroid gland. These mice develop hyperparathyroidism, bone changes reflective of elevated PTH, and parathyroid neoplasia. Further, expression of exogenous RGS5 in normal human parathyroid cells results in impaired signaling from CASR and negative feedback on PTH secretion. These results provide evidence that RGS5 can modulate signaling from CASR and support a role for RGS5 in the pathogenesis of PHPT through inhibition of CASR signaling. © 2019 American Society for Bone and Mineral Research.
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Affiliation(s)
- Nariman Balenga
- Division of General and Oncologic Surgery, Department of Surgery, University of Maryland School of Medicine, Baltimore, MD, USA
| | - James Koh
- Department of Surgery, University of California at San Francisco, San Francisco, CA, USA
| | - Pedram Azimzadeh
- Division of General and Oncologic Surgery, Department of Surgery, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Joyce Hogue
- Department of Surgery, University of California at San Francisco, San Francisco, CA, USA
| | - Mostafa Gabr
- Department of Surgery, University of California at San Francisco, San Francisco, CA, USA
| | - Joseph P Stains
- Department of Orthopaedics, University of Maryland School of Medicine, Baltimore, MD, USA
| | - John A Olson
- Division of General and Oncologic Surgery, Department of Surgery, University of Maryland School of Medicine, Baltimore, MD, USA
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35
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Lee JJ, Liu X, O'Neill D, Beggs MR, Weissgerber P, Flockerzi V, Chen XZ, Dimke H, Alexander RT. Activation of the calcium sensing receptor attenuates TRPV6-dependent intestinal calcium absorption. JCI Insight 2019; 5:128013. [PMID: 31013259 DOI: 10.1172/jci.insight.128013] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Plasma calcium (Ca2+) is maintained by amending the release of parathyroid hormone and through direct effects of the Ca2+ sensing receptor (CaSR) in the renal tubule. Combined, these mechanisms alter intestinal Ca2+ absorption by modulating 1,25-dihydroxy vitamin D3 production, bone resorption, and renal Ca2+ excretion. The CaSR is a therapeutic target in the treatment of secondary hyperparathyroidism and hypocalcemia a common complication of calcimimetic therapy. The CaSR is also expressed in intestinal epithelium, however, a direct role in regulating local intestinal Ca2+ absorption is unknown. Chronic CaSR activation decreased expression of genes involved in Ca2+ absorption. In Ussing chambers, increasing extracellular Ca2+ or basolateral application of the calcimimetic cinacalcet decreased net Ca2+ absorption across intestinal preparations acutely. Conversely, Ca2+ absorption increased with decreasing extracellular Ca2+ concentration. These responses were absent in mice expressing a non-functional TRPV6, TRPV6D541A. Cinacalcet also attenuated Ca2+ fluxes through TRPV6 in Xenopus oocytes when co-expressed with the CaSR. Moreover, the phospholipase C inhibitor, U73122, prevented cinacalcet-mediated inhibition of Ca2+ flux. These results reveal a regulatory pathway whereby activation of the CaSR in the basolateral membrane of the intestine directly attenuates local Ca2+ absorption via TRPV6 to prevent hypercalcemia and help explain how calcimimetics induce hypocalcemia.
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Affiliation(s)
- Justin J Lee
- Department of Physiology, University of Alberta, Edmonton, Alberta, Canada.,The Women's and Children's Health Research Institute, Edmonton, Alberta, Canada
| | - Xiong Liu
- Department of Physiology, University of Alberta, Edmonton, Alberta, Canada
| | - Debbie O'Neill
- Department of Physiology, University of Alberta, Edmonton, Alberta, Canada
| | - Megan R Beggs
- Department of Physiology, University of Alberta, Edmonton, Alberta, Canada.,The Women's and Children's Health Research Institute, Edmonton, Alberta, Canada
| | - Petra Weissgerber
- Experimentelle und Klinische Pharmakologie und Toxikologie, Saarland University, Hamburg, Germany
| | - Veit Flockerzi
- Experimentelle und Klinische Pharmakologie und Toxikologie, Saarland University, Hamburg, Germany
| | - Xing-Zhen Chen
- Department of Physiology, University of Alberta, Edmonton, Alberta, Canada
| | - Henrik Dimke
- Department of Cardiovascular and Renal Research, Institute of Molecular Medicine, University of Southern Denmark, Odense, Denmark.,Department of Nephrology, Odense University Hospital, Odense, Denmark
| | - R Todd Alexander
- Department of Physiology, University of Alberta, Edmonton, Alberta, Canada.,The Women's and Children's Health Research Institute, Edmonton, Alberta, Canada.,Department of Pediatrics, University of Alberta, Edmonton, Alberta, Canada
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36
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Ovejero D, Misof BM, Gafni RI, Dempster D, Zhou H, Klaushofer K, Collins MT, Roschger P. Bone Matrix Mineralization in Patients With Gain-of-Function Calcium-Sensing Receptor Mutations Is Distinctly Different From that in Postsurgical Hypoparathyroidism. J Bone Miner Res 2019; 34:661-668. [PMID: 30496603 DOI: 10.1002/jbmr.3638] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/01/2018] [Revised: 10/10/2018] [Accepted: 11/12/2018] [Indexed: 12/19/2022]
Abstract
The role of the calcium-sensing receptor (CaSR) as a regulator of parathyroid hormone secretion is well established, but its function in bone is less well defined. In an effort to elucidate the CaSR's skeletal role, bone tissue and material characteristics from patients with autosomal dominant hypocalcemia (ADH), a genetic form of primary hypoparathyroidism caused by CASR gain-of-function mutations, were compared to patients with postsurgical hypoparathyroidism (PSH). Bone structure and formation/resorption indices and mineralization density distribution (BMDD), were examined in transiliac biopsy samples from PSH (n = 13) and ADH (n = 6) patients by histomorphometry and quantitative backscatter electron imaging, respectively. Bone mineral density (BMD by DXA) and biochemical characteristics were measured at the time of the biopsy. Because both study groups comprised children and adults, all measured biopsy parameters and BMD outcomes were converted to Z-scores for comparison. Histomorphometric indices were normal and not different between ADH and PSH, with the exception of mineral apposition rate Z-score, which was higher in the ADH group. Similarly, average BMD Z-scores were normal and not different between ADH and PSH. Significant differences were observed for the BMDD: average Z-scores of mean and typical degree of mineralization (CaMean, CaPeak, respectively) were lower (p = 0.02 and p = 0.03, respectively), whereas the heterogeneity of mineralization (CaWidth) and percentage of lower mineralized areas (CaLow) were increased in ADH versus PSH (p = 0.01 and p = 0.002, respectively). The BMDD outcomes point toward a direct, PTH-independent role of the CaSR in the regulation of bone mineralization. © 2018 American Society for Bone and Mineral Research.
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Affiliation(s)
- Diana Ovejero
- Skeletal Disorders and Mineral Homeostasis Section, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, MD, USA.,Musculoskeletal Research group, Hospital del Mar Research Institute, Barcelona, Barcelona (Spain).,National Research Council, Institute of Clinical Physiology, Lecce, Italy
| | - Barbara M Misof
- Ludwig Boltzmann Institute of Osteology at the Hanusch Hospital of Social Health Insurance Vienna (WGKK) and Austrian Social Insurance for Occupational Risk (AUVA) Trauma Centre Meidling, 1st Medical Department, Hanusch Hospital, Vienna, Austria
| | - Rachel I Gafni
- Skeletal Disorders and Mineral Homeostasis Section, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, MD, USA
| | - David Dempster
- Columbia University College of Physicians & Surgeons, New York, NY, USA.,Regional Bone Center, Helen Hayes Hospital, West Haverstraw, NY, USA
| | - Hua Zhou
- Regional Bone Center, Helen Hayes Hospital, West Haverstraw, NY, USA
| | - Klaus Klaushofer
- Ludwig Boltzmann Institute of Osteology at the Hanusch Hospital of Social Health Insurance Vienna (WGKK) and Austrian Social Insurance for Occupational Risk (AUVA) Trauma Centre Meidling, 1st Medical Department, Hanusch Hospital, Vienna, Austria
| | - Michael T Collins
- Skeletal Disorders and Mineral Homeostasis Section, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, MD, USA
| | - Paul Roschger
- Ludwig Boltzmann Institute of Osteology at the Hanusch Hospital of Social Health Insurance Vienna (WGKK) and Austrian Social Insurance for Occupational Risk (AUVA) Trauma Centre Meidling, 1st Medical Department, Hanusch Hospital, Vienna, Austria
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37
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Terzioglu-Usak S, Elibol B, Dalli T, Guler C, Aysan E. Effect of Restraint Stress on Plasma PTH Concentration and Its Molecular Targets Expressions in Wistar Rats. Int J Endocrinol Metab 2018; 16:e66979. [PMID: 30464774 PMCID: PMC6216602 DOI: 10.5812/ijem.66979] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/31/2018] [Revised: 07/16/2018] [Accepted: 09/08/2018] [Indexed: 12/13/2022] Open
Abstract
BACKGROUND There are limited numbers of experimental studies related to the potential role of parathormone/parathyroid hormone (PTH) in response to psychological stress. In the current study, we aimed to cross-examine, for the first time, changes in PTH plasma concentration and the expression of its molecular targets mediated by restraint stress in rats. METHODS Male Wistar rats (n = 42) were separated into control and stressed groups. They were further divided into two groups that received chronic restraint stress (CRS) for 7 and 28 consecutive days (n = 7 for each group). Elevated plus maze and tail suspension test were used to determine the anxiety- and depressive-like behaviors of a different set of rats including stress and control groups (n = 7 for each group). The plasma levels of adrenocorticotropic hormone (ACTH), corticosterone, and intact parathormone (iPTH) were measured by enzyme-linked immunosorbent assay (ELISA). In addition, alterations in the expressions of glucocorticoid receptor (GR), calcium sensing receptor (CaSR), and parathormone receptor (PTHR1) of kidney and total thyroid gland tissues were estimated by Western Blotting. RESULTS There was no significant difference in the plasma level of iPTH while significant increases in the levels of ACTH and corticosterone were noted in the stressed-animals at day 7 and 21 (P = 0.010 and P = 0.016, respectively) of restraint stress. However, we found a negative correlation between iPTH and corticosterone levels in acute restraint stress (r = 0.771, P = 0.002). In addition, the expression of PTHR1 significantly decreased in the kidney at day 7 (P = 0.001) and in the thyroid gland at day 28 (P = 0.05) in response to CRS. CONCLUSIONS To sum up, CRS has a significant effect on the expression of parathormone receptor rather than the iPTH concentration. The present results add a new dimension to stress research through the negative effect of chronic stress on the PTH signaling pathway.
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Affiliation(s)
- Sule Terzioglu-Usak
- Department of Medical Biology, Bezmialem Vakıf University, Istanbul, Turkey
- Corresponding Author: Department of Medical Biology, Faculty of Medicine, Bezmialem Vakif University, 34093, Istanbul, Turkey. Tel: +90-5059378211, Fax: +90-3122107976,
| | - Birsen Elibol
- Department of Medical Biology, Bezmialem Vakıf University, Istanbul, Turkey
| | - Tugce Dalli
- Experimental Research Center, Bezmialem Vakıf University, Istanbul, Turkey
| | - Cansu Guler
- Department of Patients Rights, Bezmialem Vakıf University, Istanbul, Turkey
- Institute of Addiction and Forensic Sciences, Forensic Psychology and Behavioural Evidence, Istanbul Uskudar University, Istanbul, Turkey
| | - Erhan Aysan
- Department of General Surgery, Bezmialem Vakif University, Istanbul,Turkey
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38
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Iamartino L, Elajnaf T, Kallay E, Schepelmann M. Calcium-sensing receptor in colorectal inflammation and cancer: Current insights and future perspectives. World J Gastroenterol 2018; 24:4119-4131. [PMID: 30271078 PMCID: PMC6158479 DOI: 10.3748/wjg.v24.i36.4119] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/29/2018] [Revised: 07/11/2018] [Accepted: 08/01/2018] [Indexed: 02/06/2023] Open
Abstract
The extracellular calcium-sensing receptor (CaSR) is best known for its action in the parathyroid gland and kidneys where it controls body calcium homeostasis. However, the CaSR has different roles in the gastrointestinal tract, where it is ubiquitously expressed. In the colon, the CaSR is involved in controlling multiple mechanisms, including fluid transport, inflammation, cell proliferation and differentiation. Although the expression pattern and functions of the CaSR in the colonic microenvironment are far from being completely understood, evidence has been accumulating that the CaSR might play a protective role against both colonic inflammation and colorectal cancer. For example, CaSR agonists such as dipeptides have been suggested to reduce colonic inflammation, while dietary calcium was shown to reduce the risk of colorectal cancer. CaSR expression is lost in colonic malignancies, indicating that the CaSR is a biomarker for colonic cancer progression. This dual anti-inflammatory and anti-tumourigenic role of the CaSR makes it especially interesting in colitis-associated colorectal cancer. In this review, we describe the clinical and experimental evidence for the role of the CaSR in colonic inflammation and colorectal cancer, the intracellular signalling pathways which are putatively involved in these actions, and the possibilities to exploit these actions of the CaSR for future therapies of colonic inflammation and cancer.
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Affiliation(s)
- Luca Iamartino
- Institute of Pathophysiology and Allergy Research, Medical University of Vienna, Vienna 1090, Austria
| | - Taha Elajnaf
- Institute of Pathophysiology and Allergy Research, Medical University of Vienna, Vienna 1090, Austria
| | - Enikö Kallay
- Institute of Pathophysiology and Allergy Research, Medical University of Vienna, Vienna 1090, Austria
| | - Martin Schepelmann
- Institute of Pathophysiology and Allergy Research, Medical University of Vienna, Vienna 1090, Austria
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39
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Lin LY, Yeh YH, Hung GY, Lin CH, Hwang PP, Horng JL. Role of Calcium-Sensing Receptor in Mechanotransducer-Channel-Mediated Ca 2+ Influx in Hair Cells of Zebrafish Larvae. Front Physiol 2018; 9:649. [PMID: 29899708 PMCID: PMC5988855 DOI: 10.3389/fphys.2018.00649] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2017] [Accepted: 05/14/2018] [Indexed: 01/16/2023] Open
Abstract
The calcium-sensing receptor (CaSR) is an extracellular Ca2+ sensor that plays a critical role in maintaining Ca2+ homeostasis in several organs, including the parathyroid gland and kidneys. In this study, through in situ hybridization, the expression of CaSR mRNA was found in the neuromasts of zebrafish larvae. Immunohistochemistry further demonstrated that the CaSR protein was present in neuromast hair cell stereocilia and basolateral membranes. Based on the expression and subcellular localization of the CaSR in hair cells, we hypothesized that the CaSR is expressed in zebrafish lateral-line hair cells to regulate mechanotransducer (MET)-channel-mediated Ca2+ entry. Using the scanning ion-selective electrode technique, MET-channel-mediated Ca2+ influx at the stereocilia of hair cells was measured in intact larvae. Ca2+ influx was suppressed after larvae were pretreated with a CaSR activator (R-568) or high-Ca2+ (HCa) medium. Gene knockdown by using morpholino oligonucleotides decreased CaSR expression in hair cells and eliminated the effects of R-568 and HCa on Ca2+ influx. In addition, we found that treatment with R-568 attenuated neomycin-induced hair cell death. This study is the first to demonstrate that the CaSR is involved in mechanotransduction in zebrafish hair cells.
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Affiliation(s)
- Li-Yih Lin
- Department of Life Science, National Taiwan Normal University, Taipei, Taiwan
| | - Ya-Hsin Yeh
- Department of Life Science, National Taiwan Normal University, Taipei, Taiwan
| | - Giun-Yi Hung
- Department of Life Science, National Taiwan Normal University, Taipei, Taiwan.,Department of Pediatrics, Taipei Veterans General Hospital, Taipei, Taiwan.,Department of Pediatrics, Faculty of Medicine, National Yang-Ming University, Taipei, Taiwan
| | - Chia-Hao Lin
- Institute of Cellular and Organismic Biology, Academia Sinica, Taipei, Taiwan.,Department of Anatomy and Cell Biology, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan
| | - Pung-Pung Hwang
- Institute of Cellular and Organismic Biology, Academia Sinica, Taipei, Taiwan
| | - Jiun-Lin Horng
- Department of Anatomy and Cell Biology, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan
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40
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Interrelated role of Klotho and calcium-sensing receptor in parathyroid hormone synthesis and parathyroid hyperplasia. Proc Natl Acad Sci U S A 2018; 115:E3749-E3758. [PMID: 29618612 DOI: 10.1073/pnas.1717754115] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
The pathogenesis of parathyroid gland hyperplasia is poorly understood, and a better understanding is essential if there is to be improvement over the current strategies for prevention and treatment of secondary hyperparathyroidism. Here we investigate the specific role of Klotho expressed in the parathyroid glands (PTGs) in mediating parathyroid hormone (PTH) and serum calcium homeostasis, as well as the potential interaction between calcium-sensing receptor (CaSR) and Klotho. We generated mouse strains with PTG-specific deletion of Klotho and CaSR and dual deletion of both genes. We show that ablating CaSR in the PTGs increases PTH synthesis, that Klotho has a pivotal role in suppressing PTH in the absence of CaSR, and that CaSR together with Klotho regulates PTH biosynthesis and PTG growth. We utilized the tdTomato gene in our mice to visualize and collect PTGs to reveal an inhibitory function of Klotho on PTG cell proliferation. Chronic hypocalcemia and ex vivo PTG culture demonstrated an independent role for Klotho in mediating PTH secretion. Moreover, we identify an interaction between PTG-expressed CaSR and Klotho. These findings reveal essential and interrelated functions for CaSR and Klotho during parathyroid hyperplasia.
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41
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Geddes RF, Jepson RE, Forcada Y, Elliott J, Syme HM. Associations between single nucleotide polymorphisms in the calcium sensing receptor and chronic kidney disease-mineral and bone disorder in cats. Vet J 2018; 235:34-41. [PMID: 29704936 DOI: 10.1016/j.tvjl.2018.02.010] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2017] [Revised: 02/14/2018] [Accepted: 02/15/2018] [Indexed: 11/26/2022]
Abstract
Feline chronic kidney disease (CKD) is associated with high variability in severity of CKD-mineral and bone disorder (CKD-MBD). The calcium sensing receptor (CaSR) regulates circulating parathyroid hormone (PTH) and calcium concentrations. Single nucleotide polymorphisms (SNPs) in the CaSR are associated with severity of secondary renal hyperparathyroidism and total calcium concentrations in human patients receiving haemodialysis. The objective of this study was to explore associations between polymorphisms in the feline CaSR (fCaSR) and biochemical changes observed in CKD-MBD. Client owned cats (≥9years) were retrospectively included. SNP discovery was performed in 20 cats with azotaemic CKD and normal or dysregulated calcium concentrations. Non-pedigree cats (n=192) (125 with azotaemic CKD and 66 healthy), Persians (n=40) and Burmese (n=25) were genotyped for all identified SNPs using KASP. Biochemical parameters from the date of CKD diagnosis or from first visit to the clinic (healthy cats) were used. Associations between genotype and ionized calcium, total calcium, phosphate, PTH and FGF-23 were performed for non-pedigree cats using logistic regression. Sequence alignment against the fCaSR sequence revealed eight novel exonic SNPs. KASP genotyping had high accuracy (99.6%) and a low failure rate (<6%) for all SNPs. Allele frequencies varied between breeds. In non-pedigree cats, one synonymous SNP CaSR:c.1269G>A was associated with logPTH concentration (adjusted for plasma creatinine concentration), with a recessive model having the best fit (G/G vs A/A-G/A, P=0.031). Genetic variation in the fCaSR is unlikely to explain the majority of the variability in presence and severity of CKD-MBD in cats.
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Affiliation(s)
- R F Geddes
- Department of Clinical Sciences and Services, Royal Veterinary College, Hawkshead Lane, North Mymms, Hertfordshire, AL9 7TA, UK.
| | - R E Jepson
- Department of Clinical Sciences and Services, Royal Veterinary College, Hawkshead Lane, North Mymms, Hertfordshire, AL9 7TA, UK
| | - Y Forcada
- Department of Clinical Sciences and Services, Royal Veterinary College, Hawkshead Lane, North Mymms, Hertfordshire, AL9 7TA, UK
| | - J Elliott
- Department of Comparative Biomedical Sciences, Royal Veterinary College, 4 Royal College Street, London, NW1 0TU, UK
| | - H M Syme
- Department of Clinical Sciences and Services, Royal Veterinary College, Hawkshead Lane, North Mymms, Hertfordshire, AL9 7TA, UK
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42
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Cozzolino M, Pasho S, Fallabrino G, Olivi L, Gallieni M, Brancaccio D. Pathogenesis of Secondary Hyperparathyroidism. Int J Artif Organs 2018; 32:75-80. [DOI: 10.1177/039139880903200203] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Chronic renal failure is the primary cause of secondary hyperparathyroidism (SHPT). Patients with mineral metabolism disorders commonly present with low serum calcium levels, hyperphosphatemia, and calcitriol deficiency. In normal renal function subjects, parathyroid cells have a low turnover and rarely undergo mitoses. In uremic conditions, however, parathyroid glands become hyperplasic and leave quiescence. During the last ten years, new molecular mechanisms have been investigated to better understand the pathogenesis of SHPT: the emerging role of the Calcium Sensing Receptor (CaSR); the importance of the parathyroid expression of the Vitamin D receptor (VDR); the growing evidence on the central role of the Fibroblast Growth Factor 23 (FGF-23). In contrast, the discovery of a parathyroid phosphate sensor or receptor has yet to be made.
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Affiliation(s)
- Mario Cozzolino
- Renal Division, San Paolo Hospital, University of Milan, Milan - Italy
| | - Sabina Pasho
- Renal Division, San Paolo Hospital, University of Milan, Milan - Italy
| | | | - Laura Olivi
- Renal Division, San Paolo Hospital, University of Milan, Milan - Italy
| | - Maurizio Gallieni
- Renal Division, San Paolo Hospital, University of Milan, Milan - Italy
| | - Diego Brancaccio
- Renal Division, San Paolo Hospital, University of Milan, Milan - Italy
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43
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Li X, Yu L, Asuncion F, Grisanti M, Alexander S, Hensley K, Han CY, Niu QT, Dwyer D, Villasenor K, Stolina M, Dean C, Ominsky MS, Ke HZ, Tomlinson JE, Richards WG. Etelcalcetide (AMG 416), a peptide agonist of the calcium-sensing receptor, preserved cortical bone structure and bone strength in subtotal nephrectomized rats with established secondary hyperparathyroidism. Bone 2017; 105:163-172. [PMID: 28867373 DOI: 10.1016/j.bone.2017.08.026] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/30/2017] [Revised: 08/24/2017] [Accepted: 08/28/2017] [Indexed: 10/18/2022]
Abstract
Sustained elevation of parathyroid hormone (PTH) is catabolic to cortical bone, as evidenced by deterioration in bone structure (cortical porosity), and is a major factor for increased fracture risk in chronic kidney disease (CKD). Etelcalcetide (AMG 416), a novel peptide agonist of the calcium-sensing receptor, reduces PTH levels in subtotal nephrectomized (Nx) rats and in hemodialysis patients with secondary hyperparathyroidism (SHPT) in clinical studies; however, effects of etelcalcetide on bone have not been determined. In a rat model of established SHPT with renal osteodystrophy, etelcalcetide or vehicle was administered by subcutaneous (s.c.) injection to subtotal Nx rats with elevated PTH (>750pg/mL) once per day for 6weeks. Sham-operated rats receiving vehicle (s.c.) served as non-SHPT controls. Prior to treatment, significant increases in serum creatinine (2-fold), blood urea nitrogen (BUN, 3-fold), PTH (5-fold), fibroblast growth factor-23 (FGF23; 13-fold) and osteocalcin (12-fold) were observed in SHPT rats compared to non-SHPT controls. Elevations in serum creatinine and BUN were unaffected by treatment with vehicle or etelcalcetide. In contrast, etelcalcetide significantly decreased PTH, FGF23 and osteocalcin, whereas vehicle treatment did not. Cortical bone porosity increased and bone strength decreased in vehicle-treated SHPT rats compared to non-SHPT controls. Cortical bone structure improved and energy to failure was significantly greater in SHPT rats treated with etelcalcetide compared to vehicle. Mineralization lag time and marrow fibrosis were significantly reduced by etelcalcetide. In conclusion, etelcalcetide reduced bone turnover, attenuated mineralization defect and marrow fibrosis, and preserved cortical bone structure and bone strength by lowering PTH in subtotal Nx rats with established SHPT.
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Affiliation(s)
- Xiaodong Li
- Department of Cardiometabolic Disorders, Amgen Inc., Thousand Oaks, CA, USA.
| | - Longchuan Yu
- Department of Cardiometabolic Disorders, Amgen Inc., Thousand Oaks, CA, USA
| | - Frank Asuncion
- Department of Cardiometabolic Disorders, Amgen Inc., Thousand Oaks, CA, USA
| | - Mario Grisanti
- Department of Cardiometabolic Disorders, Amgen Inc., Thousand Oaks, CA, USA
| | - Shawn Alexander
- Department of Cardiometabolic Disorders, Amgen Inc., Thousand Oaks, CA, USA
| | - Kelly Hensley
- Department of Comparative Biology and Safety Sciences, Amgen Inc., Thousand Oaks, CA, USA
| | - Chun-Ya Han
- Department of Cardiometabolic Disorders, Amgen Inc., Thousand Oaks, CA, USA
| | - Qing-Tian Niu
- Department of Cardiometabolic Disorders, Amgen Inc., Thousand Oaks, CA, USA
| | - Denise Dwyer
- Department of Cardiometabolic Disorders, Amgen Inc., Thousand Oaks, CA, USA
| | - Kelly Villasenor
- Department of Cardiometabolic Disorders, Amgen Inc., Thousand Oaks, CA, USA
| | - Marina Stolina
- Department of Cardiometabolic Disorders, Amgen Inc., Thousand Oaks, CA, USA
| | - Charles Dean
- Department of Comparative Biology and Safety Sciences, Amgen Inc., Thousand Oaks, CA, USA
| | - Michael S Ominsky
- Department of Cardiometabolic Disorders, Amgen Inc., Thousand Oaks, CA, USA
| | - Hua Zhu Ke
- Department of Cardiometabolic Disorders, Amgen Inc., Thousand Oaks, CA, USA
| | - James E Tomlinson
- Department of Cardiometabolic Disorders, Amgen Inc., Thousand Oaks, CA, USA
| | - William G Richards
- Department of Cardiometabolic Disorders, Amgen Inc., Thousand Oaks, CA, USA
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44
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Howles SA, Hannan FM, Gorvin CM, Piret SE, Paudyal A, Stewart M, Hough TA, Nesbit MA, Wells S, Brown SD, Cox RD, Thakker RV. Cinacalcet corrects hypercalcemia in mice with an inactivating Gα11 mutation. JCI Insight 2017; 2:96540. [PMID: 29046478 PMCID: PMC5846897 DOI: 10.1172/jci.insight.96540] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2017] [Accepted: 09/19/2017] [Indexed: 11/17/2022] Open
Abstract
Loss-of-function mutations of GNA11, which encodes G-protein subunit α11 (Gα11), a signaling partner for the calcium-sensing receptor (CaSR), result in familial hypocalciuric hypercalcemia type 2 (FHH2). FHH2 is characterized by hypercalcemia, inappropriately normal or raised parathyroid hormone (PTH) concentrations, and normal or low urinary calcium excretion. A mouse model for FHH2 that would facilitate investigations of the in vivo role of Gα11 and the evaluation of calcimimetic drugs, which are CaSR allosteric activators, is not available. We therefore screened DNA from > 10,000 mice treated with the chemical mutagen N-ethyl-N-nitrosourea (ENU) for GNA11 mutations and identified a Gα11 variant, Asp195Gly (D195G), which downregulated CaSR-mediated intracellular calcium signaling in vitro, consistent with it being a loss-of-function mutation. Treatment with the calcimimetic cinacalcet rectified these signaling responses. In vivo studies showed mutant heterozygous (Gna11+/195G) and homozygous (Gna11195G/195G) mice to be hypercalcemic with normal or increased plasma PTH concentrations and normal urinary calcium excretion. Cinacalcet (30mg/kg orally) significantly reduced plasma albumin–adjusted calcium and PTH concentrations in Gna11+/195G and Gna11195G/195G mice. Thus, our studies have established a mouse model with a germline loss-of-function Gα11 mutation that is representative for FHH2 in humans and demonstrated that cinacalcet can correct the associated abnormalities of plasma calcium and PTH. Cinacalcet corrects hypercalcemia in a mouse model for familial hypocalciuric hypercalcemia type 2 (FHH2) caused by a germline loss-of-function G-protein subunit α11 (Gα11) mutation, Asp195Gly.
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Affiliation(s)
- Sarah A Howles
- Academic Endocrine Unit, Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - Fadil M Hannan
- Academic Endocrine Unit, Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom.,Department of Musculoskeletal Biology, Institute of Ageing and Chronic Disease, University of Liverpool, Liverpool, United Kingdom
| | - Caroline M Gorvin
- Academic Endocrine Unit, Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - Sian E Piret
- Academic Endocrine Unit, Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - Anju Paudyal
- Mammalian Genetics Unit and Mary Lyon Centre, Medical Research Council (MRC) Harwell Institute, Harwell Science and Innovation Campus, United Kingdom
| | - Michelle Stewart
- Mammalian Genetics Unit and Mary Lyon Centre, Medical Research Council (MRC) Harwell Institute, Harwell Science and Innovation Campus, United Kingdom
| | - Tertius A Hough
- Mammalian Genetics Unit and Mary Lyon Centre, Medical Research Council (MRC) Harwell Institute, Harwell Science and Innovation Campus, United Kingdom
| | - M Andrew Nesbit
- Academic Endocrine Unit, Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom.,Biomedical Sciences Research Institute, Ulster University, Coleraine, United Kingdom
| | - Sara Wells
- Mammalian Genetics Unit and Mary Lyon Centre, Medical Research Council (MRC) Harwell Institute, Harwell Science and Innovation Campus, United Kingdom
| | - Stephen Dm Brown
- Mammalian Genetics Unit and Mary Lyon Centre, Medical Research Council (MRC) Harwell Institute, Harwell Science and Innovation Campus, United Kingdom
| | - Roger D Cox
- Mammalian Genetics Unit and Mary Lyon Centre, Medical Research Council (MRC) Harwell Institute, Harwell Science and Innovation Campus, United Kingdom
| | - Rajesh V Thakker
- Academic Endocrine Unit, Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom
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Li H, Sun S, Chen J, Xu G, Wang H, Qian Q. Genetics of Magnesium Disorders. KIDNEY DISEASES 2017; 3:85-97. [PMID: 29344503 DOI: 10.1159/000477730] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/27/2017] [Revised: 05/23/2017] [Indexed: 12/30/2022]
Abstract
Background Magnesium (Mg2+), the second most abundant cation in the cell, is woven into a multitude of cellular functions. Dysmagnesemia is associated with multiple diseases and, when severe, can be life-threatening. Summary This review discusses Mg2+ homeostasis and function with specific focus on renal Mg2+ handling. Intrarenal channels and transporters related to Mg2+ absorption are discussed. Unraveling the rare genetic diseases with manifestations of dysmagnesemia has greatly increased our understanding of the complex and intricate regulatory network in the kidney, specifically, functions of tight junction proteins including claudin-14, -16, -19, and -10; apical ion channels including: TRPM6, Kv1.1, and ROMK; small regulatory proteins including AC3 and ANK3; and basolateral proteins including EGF receptor, γ-subunit (FXYD2) of Na-K-ATPase, Kir4.1, CaSR, CNNM2, and SLC41A. Although our understanding of Mg2+ handling of the kidney has expanded considerably in the last two decades, many questions remain. Future studies are needed to elucidate a multitude of unknown aspects of Mg2+ handling in the kidney. Key Message Understanding rare and genetic diseases of Mg2+ dysregulation has expanded our knowledge and furthers the development of strategies for preventing and managing dysmagnesemia.
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Affiliation(s)
- Heng Li
- Kidney Disease Center, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, China.,Division of Nephrology and Hypertension, Department of Medicine, Mayo Clinic College of Medicine, Rochester, Minnesota, USA
| | - Shiren Sun
- Department of Nephrology, Xijing Hospital, The Fourth Military Medical University, Xian, China
| | - Jianghua Chen
- Kidney Disease Center, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, China
| | - Goushuang Xu
- Department of Nephrology, Xijing Hospital, The Fourth Military Medical University, Xian, China
| | - Hanmin Wang
- Department of Nephrology, Xijing Hospital, The Fourth Military Medical University, Xian, China
| | - Qi Qian
- Division of Nephrology and Hypertension, Department of Medicine, Mayo Clinic College of Medicine, Rochester, Minnesota, USA
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Gorvin CM, Rogers A, Stewart M, Paudyal A, Hough TA, Teboul L, Wells S, Brown SD, Cox RD, Thakker RV. N-ethyl-N-nitrosourea-Induced Adaptor Protein 2 Sigma Subunit 1 ( Ap2s1) Mutations Establish Ap2s1 Loss-of-Function Mice. JBMR Plus 2017; 1:3-15. [PMID: 29479578 PMCID: PMC5824975 DOI: 10.1002/jbm4.10001] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
The adaptor protein‐2 sigma subunit (AP2σ), encoded by AP2S1, forms a heterotetrameric complex, with AP2α, AP2β, and AP2μ subunits, that is pivotal for clathrin‐mediated endocytosis, and AP2σ loss‐of‐function mutations impair internalization of the calcium‐sensing receptor (CaSR), a G‐protein–coupled receptor, and cause familial hypocalciuric hypercalcemia type‐3 (FHH3). Mice with AP2σ mutations that would facilitate investigations of the in vivo role of AP2σ, are not available, and we therefore embarked on establishing such mice. We screened >10,000 mice treated with the mutagen N‐ethyl‐N‐nitrosourea (ENU) for Ap2s1 mutations and identified 5 Ap2s1 variants, comprising 2 missense (Tyr20Asn and Ile123Asn) and 3 intronic base substitutions, one of which altered the invariant donor splice site dinucleotide gt to gc. Three‐dimensional modeling and cellular expression of the missense Ap2s1 variants did not reveal them to alter AP2σ structure or CaSR‐mediated signaling, but investigation of the donor splice site variant revealed it to result in an in‐frame deletion of 17 evolutionarily conserved amino acids (del17) that formed part of the AP2σ α1‐helix, α1‐β3 loop, and β3 strand. Heterozygous mutant mice (Ap2s1+/del17) were therefore established, and these had AP2σ haplosufficiency but were viable with normal appearance and growth. Ap2s1+/del17 mice, when compared with Ap2s1+/+ mice, also had normal plasma concentrations of calcium, phosphate, magnesium, creatinine, urea, sodium, potassium, and alkaline phosphatase activity; normal urinary fractional excretion of calcium, phosphate, sodium, and potassium; and normal plasma parathyroid hormone (PTH) and 1,25‐dihydroxyvitamin D (1,25(OH)2) concentrations. However, homozygous Ap2s1del17/del17 mice were non‐viable and died between embryonic days 3.5 and 9.5 (E3.5–9.5), thereby indicating that AP2σ likely has important roles at the embryonic patterning stages and organogenesis of the heart, thyroid, liver, gut, lungs, pancreas, and neural systems. Thus, our studies have established a mutant mouse model that is haplosufficient for AP2σ. © 2017 The Authors. JBMR Plus is published by Wiley Periodicals, Inc. on behalf of the American Society for Bone and Mineral Research.
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Affiliation(s)
- Caroline M Gorvin
- Academic Endocrine Unit, Radcliffe Department of Medicine, University of Oxford, Oxford Centre for Diabetes, Endocrinology, and Metabolism (OCDEM), Churchill Hospital, Oxford, UK
| | - Angela Rogers
- Academic Endocrine Unit, Radcliffe Department of Medicine, University of Oxford, Oxford Centre for Diabetes, Endocrinology, and Metabolism (OCDEM), Churchill Hospital, Oxford, UK
| | - Michelle Stewart
- Mary Lyon Centre and Mammalian Genetics Unit, Medical Research Council Harwell Institute, Harwell Campus, Oxfordshire, UK
| | - Anju Paudyal
- Mary Lyon Centre and Mammalian Genetics Unit, Medical Research Council Harwell Institute, Harwell Campus, Oxfordshire, UK
| | - Tertius A Hough
- Mary Lyon Centre and Mammalian Genetics Unit, Medical Research Council Harwell Institute, Harwell Campus, Oxfordshire, UK
| | - Lydia Teboul
- Mary Lyon Centre and Mammalian Genetics Unit, Medical Research Council Harwell Institute, Harwell Campus, Oxfordshire, UK
| | - Sara Wells
- Mary Lyon Centre and Mammalian Genetics Unit, Medical Research Council Harwell Institute, Harwell Campus, Oxfordshire, UK
| | - Steve Dm Brown
- Mary Lyon Centre and Mammalian Genetics Unit, Medical Research Council Harwell Institute, Harwell Campus, Oxfordshire, UK
| | - Roger D Cox
- Mary Lyon Centre and Mammalian Genetics Unit, Medical Research Council Harwell Institute, Harwell Campus, Oxfordshire, UK
| | - Rajesh V Thakker
- Academic Endocrine Unit, Radcliffe Department of Medicine, University of Oxford, Oxford Centre for Diabetes, Endocrinology, and Metabolism (OCDEM), Churchill Hospital, Oxford, UK
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47
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Chiara V, Sabrina C. Epigenetics of human parathyroid tumors. INTERNATIONAL JOURNAL OF ENDOCRINE ONCOLOGY 2017. [DOI: 10.2217/ije-2017-0002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
Parathyroid tumors are common endocrine neoplasia associated with primary hyperparathyroidism, a metabolic disorder sustained by parathormone hypersecretion. The epigenetic scenario in parathyroid tumors is beginning to be decoded. Here, main findings are reviewed: hypermethylation of specific DNA CpG islands has been described, despite global DNA promoter hypomethylation was not detectable; embryonic-related miRNAs, belonging to the C19MC and miR‐371-373 clusters, and miR‐296, are deregulated; expression of histone H1.2 and H2B is increased; expression of histone methyltransferase EZH2, BMI1 and RIZ1 is impaired; the tumor suppressor HIC1, MEN1 and CDC73 gene products, key molecules in parathyroid tumorigenesis, may be involved in epigenetic aberrant changes. Epigenetic changes are more frequent and more consistent in parathyroid malignancies, and positively correlated with severity of primary hyperparathyroidism.
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Affiliation(s)
- Verdelli Chiara
- Laboratory of Experimental Endocrinology, IRCCS Istituto Ortopedico Galeazzi, Milan, Italy
| | - Corbetta Sabrina
- Endocrinology Unit, Department of Biomedical Sciences for Health, University of Milan, IRCCS Istituto Ortopedico Galeazzi, Milan, Italy
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48
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Harada K, Inoue A, Yamauchi A, Fujii A. [The pharmacological profile and the clinical efficacy of the world's 1st intravenous calcimimetics; etelcalcetide hydrochloride (Parsabiv ®)]. Nihon Yakurigaku Zasshi 2017; 150:98-113. [PMID: 28794306 DOI: 10.1254/fpj.150.98] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
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Kersten S, Arjona FJ. Ion transport in the zebrafish kidney from a human disease angle: possibilities, considerations, and future perspectives. Am J Physiol Renal Physiol 2017; 312:F172-F189. [DOI: 10.1152/ajprenal.00425.2016] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2016] [Revised: 11/11/2016] [Accepted: 11/14/2016] [Indexed: 12/31/2022] Open
Abstract
Unique experimental advantages, such as its embryonic/larval transparency, high-throughput nature, and ease of genetic modification, underpin the rapid emergence of the zebrafish ( Danio rerio) as a preeminent model in biomedical research. Particularly in the field of nephrology, the zebrafish provides a promising model for studying the physiological implications of human solute transport processes along consecutive nephron segments. However, although the zebrafish might be considered a valuable model for numerous renal ion transport diseases and functional studies of many channels and transporters, not all human renal electrolyte transport mechanisms and human diseases can be modeled in the zebrafish. With this review, we explore the ontogeny of zebrafish renal ion transport, its nephron structure and function, and thereby demonstrate the clinical translational value of this model. By critical assessment of genomic and amino acid conservation of human proteins involved in renal ion handling (channels, transporters, and claudins), kidney and nephron segment conservation, and renal electrolyte transport physiology in the zebrafish, we provide researchers and nephrologists with an indication of the possibilities and considerations of the zebrafish as a model for human renal ion transport. Combined with advanced techniques envisioned for the future, implementation of the zebrafish might expand beyond unraveling pathophysiological mechanisms that underlie distinct genetic or environmentally, i.e., pharmacological and lifestyle, induced renal transport deficits. Specifically, the ease of drug administration and the exploitation of improved genetic approaches might argue for the adoption of the zebrafish as a model for preclinical personalized medicine for distinct renal diseases and renal electrolyte transport proteins.
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Affiliation(s)
- Simone Kersten
- Department of Physiology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, The Netherlands; and
- Nephrology Division, Department of Medicine, Massachusetts General Hospital, Charlestown, Massachusetts
| | - Francisco J. Arjona
- Department of Physiology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, The Netherlands; and
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50
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Ringer C, Tune S, Bertoune MA, Schwarzbach H, Tsujikawa K, Weihe E, Schütz B. Disruption of calcitonin gene-related peptide signaling accelerates muscle denervation and dampens cytotoxic neuroinflammation in SOD1 mutant mice. Cell Mol Life Sci 2017; 74:339-358. [PMID: 27554772 PMCID: PMC11107523 DOI: 10.1007/s00018-016-2337-4] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2016] [Revised: 08/06/2016] [Accepted: 08/08/2016] [Indexed: 12/13/2022]
Abstract
Amyotrophic lateral sclerosis (ALS) is a fatal motor neuron disease. Neuronal vacuolization and glial activation are pathologic hallmarks in the superoxide dismutase 1 (SOD1) mouse model of ALS. Previously, we found the neuropeptide calcitonin gene-related peptide (CGRP) associated with vacuolization and astrogliosis in the spinal cord of these mice. We now show that CGRP abundance positively correlated with the severity of astrogliosis, but not vacuolization, in several motor and non-motor areas throughout the brain. SOD1 mice harboring a genetic depletion of the βCGRP isoform showed reduced CGRP immunoreactivity associated with vacuolization, while motor functions, body weight, survival, and astrogliosis were not altered. When CGRP signaling was completely disrupted through genetic depletion of the CGRP receptor component, receptor activity-modifying protein 1 (RAMP1), hind limb muscle denervation, and loss of muscle performance were accelerated, while body weight and survival were not affected. Dampened neuroinflammation, i.e., reduced levels of astrogliosis in the brain stem already in the pre-symptomatic disease stage, and reduced microgliosis and lymphocyte infiltrations during the late disease phase were additional neuropathology features in these mice. On the molecular level, mRNA expression levels of brain-derived neurotrophic factor (BDNF) and those of the anti-inflammatory cytokine interleukin 6 (IL-6) were elevated, while those of several pro-inflammatory cytokines found reduced in the brain stem of RAMP1-deficient SOD1 mice at disease end stage. Our results thus identify an important, possibly dual role of CGRP in ALS pathogenesis.
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Affiliation(s)
- Cornelia Ringer
- Department of Molecular Neurosciences, Institute of Anatomy and Cell Biology, Philipps-University, Robert-Koch-Strasse 8, 35037, Marburg, Germany
- Institute of Anatomy, University of Lübeck, Lübeck, Germany
| | - Sarah Tune
- Department of Physiology, University of Lübeck, Lübeck, Germany
| | - Mirjam A Bertoune
- Department of Medical Cell Biology, Institute of Anatomy and Cell Biology, Philipps-University, Marburg, Germany
| | - Hans Schwarzbach
- Department of Medical Cell Biology, Institute of Anatomy and Cell Biology, Philipps-University, Marburg, Germany
| | - Kazutake Tsujikawa
- Laboratory of Molecular and Cellular Physiology, Graduate School of Pharmaceutical Sciences, Osaka University, Yamadaoka, Suita, Osaka, Japan
| | - Eberhard Weihe
- Department of Molecular Neurosciences, Institute of Anatomy and Cell Biology, Philipps-University, Robert-Koch-Strasse 8, 35037, Marburg, Germany.
| | - Burkhard Schütz
- Department of Molecular Neurosciences, Institute of Anatomy and Cell Biology, Philipps-University, Robert-Koch-Strasse 8, 35037, Marburg, Germany.
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