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Cozzolino M, Cianciolo G, Podestà MA, Ciceri P, Galassi A, Gasperoni L, La Manna G. Current Therapy in CKD Patients Can Affect Vitamin K Status. Nutrients 2020; 12:nu12061609. [PMID: 32486167 PMCID: PMC7352600 DOI: 10.3390/nu12061609] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2020] [Revised: 05/27/2020] [Accepted: 05/28/2020] [Indexed: 12/15/2022] Open
Abstract
Chronic kidney disease (CKD) patients have a higher risk of cardiovascular (CVD) morbidity and mortality compared to the general population. The links between CKD and CVD are not fully elucidated but encompass both traditional and uremic-related risk factors. The term CKD-mineral and bone disorder (CKD-MBD) indicates a systemic disorder characterized by abnormal levels of calcium, phosphate, PTH and FGF-23, along with vitamin D deficiency, decreased bone mineral density or altered bone turnover and vascular calcification. A growing body of evidence shows that CKD patients can be affected by subclinical vitamin K deficiency; this has led to identifying such a condition as a potential therapeutic target given the specific role of Vitamin K in metabolism of several proteins involved in bone and vascular health. In other words, we can hypothesize that vitamin K deficiency is the common pathogenetic link between impaired bone mineralization and vascular calcification. However, some of the most common approaches to CKD, such as (1) low vitamin K intake due to nutritional restrictions, (2) warfarin treatment, (3) VDRA and calcimimetics, and (4) phosphate binders, may instead have the opposite effects on vitamin K metabolism and storage in CKD patients.
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Affiliation(s)
- Mario Cozzolino
- Renal Division, ASST Santi Paolo e Carlo, Department of Health Sciences, University of Milan, 20142 Milan, Italy; (M.C.); (M.A.P.); (A.G.)
| | - Giuseppe Cianciolo
- Nephrology, Dialysis and Renal Transplant Unit, Department of Experimental Diagnostic and Specialty Medicine (DIMES), S. Orsola Hospital, University of Bologna, 40126 Bologna, Italy; (G.C.); (L.G.)
| | - Manuel Alfredo Podestà
- Renal Division, ASST Santi Paolo e Carlo, Department of Health Sciences, University of Milan, 20142 Milan, Italy; (M.C.); (M.A.P.); (A.G.)
| | - Paola Ciceri
- Renal Research Laboratory, Department of Nephrology, Dialysis and Renal Transplant, Fondazione IRCCS Ca’ Granda, Ospedale Maggiore Policlinico, 20122 Milan, Italy;
| | - Andrea Galassi
- Renal Division, ASST Santi Paolo e Carlo, Department of Health Sciences, University of Milan, 20142 Milan, Italy; (M.C.); (M.A.P.); (A.G.)
| | - Lorenzo Gasperoni
- Nephrology, Dialysis and Renal Transplant Unit, Department of Experimental Diagnostic and Specialty Medicine (DIMES), S. Orsola Hospital, University of Bologna, 40126 Bologna, Italy; (G.C.); (L.G.)
| | - Gaetano La Manna
- Nephrology, Dialysis and Renal Transplant Unit, Department of Experimental Diagnostic and Specialty Medicine (DIMES), S. Orsola Hospital, University of Bologna, 40126 Bologna, Italy; (G.C.); (L.G.)
- Correspondence: ; Tel.: +39-051214-3255
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Chen Y, Gao Y, Tao Y, Lin D, An S. Identification of a Calcium-sensing Receptor in Human Dental Pulp Cells That Regulates Mineral Trioxide Aggregate–induced Mineralization. J Endod 2019; 45:907-916. [DOI: 10.1016/j.joen.2019.03.019] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2019] [Revised: 02/28/2019] [Accepted: 03/28/2019] [Indexed: 12/23/2022]
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Vitamin K in Chronic Kidney Disease. Nutrients 2019; 11:nu11010168. [PMID: 30646590 PMCID: PMC6356438 DOI: 10.3390/nu11010168] [Citation(s) in RCA: 46] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2018] [Revised: 12/13/2018] [Accepted: 01/11/2019] [Indexed: 12/19/2022] Open
Abstract
Vitamin K is a composite term referring to a group of fat-soluble vitamins that function as a cofactor for the enzyme γ-glutamyl carboxylase (GGCX), which activates a number of vitamin K-dependent proteins (VKDPs) involved in haemostasis and vascular and bone health. Accumulating evidence demonstrates that chronic kidney disease (CKD) patients suffer from subclinical vitamin K deficiency, suggesting that this represents a population at risk for the biological consequences of poor vitamin K status. This deficiency might be caused by exhaustion of vitamin K due to its high requirements by vitamin K-dependent proteins to inhibit calcification.
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Ruderman I, Holt SG, Hewitson TD, Smith ER, Toussaint ND. Current and potential therapeutic strategies for the management of vascular calcification in patients with chronic kidney disease including those on dialysis. Semin Dial 2018; 31:487-499. [PMID: 29733462 DOI: 10.1111/sdi.12710] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Patients with CKD have accelerated vascular stiffening contributing significantly to excess cardiovascular morbidity and mortality. Much of the arterial stiffening is thought to involve vascular calcification (VC), but the pathogenesis of this phenomenon is complex, resulting from a disruption of the balance between promoters and inhibitors of calcification in a uremic milieu, along with derangements in calcium and phosphate metabolic pathways. Management of traditional cardiovascular risk factors to reduce VC may be influential but has not been shown to significantly improve mortality. Control of mineral metabolism may potentially reduce the burden of VC, although using conventional approaches of restricting dietary phosphate, administering phosphate binders, and use of active vitamin D and calcimimetics, remains controversial because recommended biochemical targets are hard to achieve and clinical relevance hard to define. Increasing time on dialysis is perhaps another therapy with potential effectiveness in this area. Despite current treatments, cardiovascular morbidity and mortality remain high in this group. Novel therapies for addressing VC include magnesium and vitamin K supplementation, which are currently being investigated in large randomized control trials. Other therapeutic targets include crystallization inhibitors, ligand trap for activin receptors and BMP-7. This review summarizes current treatment strategies and therapeutic targets for the future management of VC in patients with CKD.
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Affiliation(s)
- Irene Ruderman
- Department of Nephrology, The Royal Melbourne Hospital, Parkville, Vic., Australia.,Department of Medicine (RMH), The University of Melbourne, Melbourne, Vic., Australia
| | - Stephen G Holt
- Department of Nephrology, The Royal Melbourne Hospital, Parkville, Vic., Australia.,Department of Medicine (RMH), The University of Melbourne, Melbourne, Vic., Australia
| | - Tim D Hewitson
- Department of Nephrology, The Royal Melbourne Hospital, Parkville, Vic., Australia.,Department of Medicine (RMH), The University of Melbourne, Melbourne, Vic., Australia
| | - Edward R Smith
- Department of Nephrology, The Royal Melbourne Hospital, Parkville, Vic., Australia.,Department of Medicine (RMH), The University of Melbourne, Melbourne, Vic., Australia
| | - Nigel D Toussaint
- Department of Nephrology, The Royal Melbourne Hospital, Parkville, Vic., Australia.,Department of Medicine (RMH), The University of Melbourne, Melbourne, Vic., Australia
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Harper E, Forde H, Davenport C, Rochfort KD, Smith D, Cummins PM. Vascular calcification in type-2 diabetes and cardiovascular disease: Integrative roles for OPG, RANKL and TRAIL. Vascul Pharmacol 2016; 82:30-40. [DOI: 10.1016/j.vph.2016.02.003] [Citation(s) in RCA: 88] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2015] [Revised: 02/01/2016] [Accepted: 02/21/2016] [Indexed: 12/14/2022]
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Fusaro M, Giannini S, Gallieni M, Noale M, Tripepi G, Rossini M, Messa P, Rigotti P, Pati T, Barbisoni F, Piccoli A, Aghi A, Alessi M, Bonfante L, Fabris F, Zambon S, Sella S, Iervasi G, Plebani M. Calcimimetic and vitamin D analog use in hemodialyzed patients is associated with increased levels of vitamin K dependent proteins. Endocrine 2016; 51:333-41. [PMID: 26130027 DOI: 10.1007/s12020-015-0673-z] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/09/2015] [Accepted: 06/20/2015] [Indexed: 12/24/2022]
Abstract
Matrix Gla protein (MGP) and bone Gla protein (BGP) are two vitamin K-dependent proteins (VKDPs) involved in the regulation of vascular calcification (VC). We carried out a secondary analysis of the VIKI study to evaluate associations between drug consumption and VKDP levels in 387 hemodialyzed patients. The VIKI study assessed the prevalence of vitamin K deficiency in hemodialysis patients. We evaluated drug consumption, determined BGP and MGP levels, and verified the presence of any vertebral fractures (VF) and VC by spine radiographs. Total BGP levels were twice as high with calcimimetics versus no calcimimetics (290 vs. 158.5 mcg/L, p < 0.0001) and 69 % higher with vitamin D analogs (268 vs. 159 mcg/L, p < 0.0001). Total MGP was 19 % higher with calcimimetics (21.5 vs. 18.1 mcg/L, p = 0.04) and 54 % higher with calcium acetate (27.9 vs. 18.1 mcg/L, p = 0.003); no difference was found with vitamin D analogs (21.1 vs. 18.3 mcg/L, p = 0.43). Median Total BGP level was 29 % lower in patients with ≥1 VF (151 vs. 213 mcg/L, p = 0.0091) and 36 % lower in patients with VC (164 vs. 262.1 mcg/L, p = 0.0003). In non-survivors, median BGP and MGP were lower, but only for MGP this difference reached the statistical significance (152 vs. 191 mcg/L, p = 0.20 and 15.0 vs. 19.7 mcg/L, p = 0.02, respectively). Pending studies on vitamin K supplementation, calcimimetics, and vitamin D analogs may play a role in preserving vitamin K-dependent protein activity, thus contributing to bone and vascular health in CKD patients.
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Affiliation(s)
- Maria Fusaro
- National Research Council (CNR), Neuroscience Institute, Via Giustiniani, 2, 35128, Padua, Italy.
| | - Sandro Giannini
- Department of Medicine, Clinica Medica 1, University of Padua, Padua, Italy
| | - Maurizio Gallieni
- Nephrology and Dialysis Unit, San Carlo Borromeo Hospital, Department of Biomedical and Clinical Sciences "L. Sacco", University of Milan, Milan, Italy
| | - Marianna Noale
- National Research Council (CNR), Neuroscience Institute, Via Giustiniani, 2, 35128, Padua, Italy
| | - Giovanni Tripepi
- CNR-IFC Pathophysiology of Renal Diseases and Hypertension Unit, Reggio Calabria, Italy
| | - Maurizio Rossini
- Rheumatology Unit, Department of Medicine, University of Verona, Verona, Italy
| | - Piergiorgio Messa
- Fondazione Ca' Granda-IRCCS Ospedale Maggiore Policlinico, Milan, Italy
| | - Paolo Rigotti
- Kidney - Pancreas Transplant Unit, Department of Surgical, Oncological and Gastroenterological Sciences, University of Padua, Padua, Italy
| | - Tecla Pati
- Nephrology and Dialysis Unit, Hospital of Rovigo, Rovigo, Italy
| | | | | | - Andrea Aghi
- Nephrology Unit, University of Padua, Padua, Italy
| | | | | | - Fabrizio Fabris
- Department of Medicine, Clinica Medica 1, University of Padua, Padua, Italy
| | - Sabina Zambon
- Department of Medicine, Clinica Medica 1, University of Padua, Padua, Italy
| | - Stefania Sella
- Department of Medicine, Clinica Medica 1, University of Padua, Padua, Italy
| | | | - Mario Plebani
- Laboratory Medicine Unit, Department of Medicine, University of Padua, Padua, Italy
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Calcium-sensing receptor-mediated osteogenic and early-stage neurogenic differentiation in umbilical cord matrix mesenchymal stem cells from a large animal model. PLoS One 2014; 9:e111533. [PMID: 25379789 PMCID: PMC4224416 DOI: 10.1371/journal.pone.0111533] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2013] [Accepted: 10/03/2014] [Indexed: 01/15/2023] Open
Abstract
BACKGROUND Umbilical cord matrix mesenchymal stem cells (UCM-MSCs) present a wide range of potential therapeutical applications. The extracellular calcium-sensing receptor (CaSR) regulates physiological and pathological processes. We investigated, in a large animal model, the involvement of CaSR in triggering osteogenic and neurogenic differentiation of two size-sieved UCM-MSC lines, by using AMG641, a novel potent research calcimimetic acting as CaSR agonist. METHODOLOGY/PRINCIPAL FINDINGS Large (>8 µm in diameter) and small (<8 µm) equine UCM-MSC lines were cultured in medium with high calcium (Ca2+) concentration ([Ca2+]o; 2.87 mM) and dose-response effects of AMG641 (0.01 to 3µM) on cell proliferation were evaluated. Both cell lines were then cultured in osteogenic or neurogenic differentiation medium containing: 1) low [Ca2+]o (0.37 mM); 2) high [Ca2+]o (2.87 mM); 3) AMG641 (0.05, 0.1 or 1 µM) with high [Ca2+]o and 4) the CaSR antagonist NPS2390 (10 mM for 30 min) followed by incubation with AMG641 in high [Ca2+]o. Expression of osteogenic or neurogenic differentiation biomarkers was compared among groups. In both cell lines, AMG641 dose-dependently increased cell proliferation (up to P<0.001). Osteogenic molecular markers expression was differentially regulated by AMG641, with stimulatory (OPN up-regulation) in large or inhibitory (RUNX2 and OPN down-regulation) effects in small cells, respectively. AMG641 significantly increased alkaline phosphatase activity and calcium phosphate deposition in both cell lines. Following treatment with AMG641 during osteogenic differentiation, in both cell lines CaSR expression was inversely related to that of osteogenic markers and inhibition of CaSR by NPS2390 blocked AMG641-dependent responses. Early-stage neurogenic differentiation was promoted/triggered by AMG641 in both cell lines, as Nestin and CaSR mRNA transcription up-regulation were observed. CONCLUSIONS/SIGNIFICANCE Calcium- and AMG641-induced CaSR stimulation promoted in vitro proliferation and osteogenic and early-stage neurogenic differentiation of UCM-MSCs. CaSR activation may play a fundamental role in selecting specific differentiation checkpoints of these two differentiation routes, as related to cell commitment status.
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Hénaut L, Boudot C, Massy ZA, Lopez-Fernandez I, Dupont S, Mary A, Drüeke TB, Kamel S, Brazier M, Mentaverri R. Calcimimetics increase CaSR expression and reduce mineralization in vascular smooth muscle cells: mechanisms of action. Cardiovasc Res 2013; 101:256-65. [DOI: 10.1093/cvr/cvt249] [Citation(s) in RCA: 60] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Latif F, Khalid MM, Khan F, Omar Z, Ali FA. Role of hyperphosphatemia-mediated vascular calcification in cardiovascular outcomes and its management. J Cardiovasc Med (Hagerstown) 2013; 14:410-5. [DOI: 10.2459/jcm.0b013e32835ec53d] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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Abstract
The calcium-sensing receptor (CaR) is the key controller of extracellular calcium (Ca(2+)(o)) homeostasis via its regulation of parathyroid hormone (PTH) secretion and renal Ca(2+) reabsorption. The CaR-selective calcimimetic drug Cinacalcet stimulates the CaR to suppress PTH secretion in chronic kidney disease and represents the world's first clinically available receptor positive allosteric modulator (PAM). Negative CaR allosteric modulators (NAMs), known as calcilytics, can increase PTH secretion and are being investigated as possible bone anabolic treatments against age-related osteoporosis. Here we address the current state of development and clinical use of a series of positive and negative CaR modulators. In addition, clinical CaR mutations and transgenic mice carrying tissue-specific CaR deletions have provided a novel understanding of the relative functional importance of CaR in both calciotropic tissues and those elsewhere in the body. The development of CaR-selective modulators and signalling reagents have provided us with a more detailed appreciation of how the CaR signals in vivo. Thus, both of these areas of CaR research will be reviewed.
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Affiliation(s)
- Donald T Ward
- Faculty of Life Sciences, The University of ManchesterManchester, UK
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Zheng CM, Lu KC, Wu CC, Hsu YH, Lin YF. Association of Serum Phosphate and Related Factors in ESRD-Related Vascular Calcification. Int J Nephrol 2011; 2011:939613. [PMID: 21660259 PMCID: PMC3108197 DOI: 10.4061/2011/939613] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2011] [Accepted: 03/12/2011] [Indexed: 12/16/2022] Open
Abstract
Vascular calcification is common in ESRD patients and is important in increasing mortality from cardiovascular complications in these patients. Hyperphosphatemia related to chronic kidney disease is increasingly known as major stimulus for vascular calcification. Hyperphosphatemia and vascular calcification become popular discussion among nephrologist environment more than five decades, and many researches have been evolved. Risk factors for calcification are nowadays focused for the therapeutic prevention of vascular calcification with the hope of reducing cardiovascular complications.
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Affiliation(s)
- Cai-Mei Zheng
- Division of Nephrology, Department of Medicine, Taipei Medical University-Shuang Ho Hospital, Taipei Medical University, Taipei 235, Taiwan
| | - Kuo-Cheng Lu
- Department of Medicine, Cardinal Tien Hospital, School of Medicine, Fu Jen Catholic University, Taipei 231, Taiwan
| | - Chia-Chao Wu
- Division of Nephrology, Department of Medicine, Tri-Service General Hospital, National Defense Medical Center, Taipei 114, Taiwan
- Graduate Institute of Microbiology and Immunology, National Defense Medical Center, Taipei 114, Taiwan
| | - Yung-Ho Hsu
- Division of Nephrology, Department of Medicine, Taipei Medical University-Shuang Ho Hospital, Taipei Medical University, Taipei 235, Taiwan
| | - Yuh-Feng Lin
- Division of Nephrology, Department of Medicine, Taipei Medical University-Shuang Ho Hospital, Taipei Medical University, Taipei 235, Taiwan
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[Atypical obstruction during a hemodialysis catheter replacement]. Nephrol Ther 2011; 7:188-90. [PMID: 21296633 DOI: 10.1016/j.nephro.2010.12.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2010] [Revised: 12/08/2010] [Accepted: 12/11/2010] [Indexed: 11/20/2022]
Abstract
We followed a 60-year-old woman in our department for a vascular chronic kidney disease. The peritoneal dialysis was stopped because of a Candida albicans catheter infection. As the patient refused the arterio-venous fistula creation, we have placed a central venous catheter (Medcomp 32cm). Because the instability of the cuff, we decided to remove and change it by another one (Quinton 40cm). The discovery of an important cylindrical calcification has complicated the manipulation requiring tranquility and agility. The finding of a massive calcification is uncommon and confirms the major risk of calcification in chronic kidney disease patients.
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Mizobuchi M, Ogata H, Hosaka N, Kumata C, Nakazawa A, Kondo F, Koiwa F, Kinugasa E, Akizawa T. Effects of calcimimetic combined with an angiotensin-converting enzyme inhibitor on uremic cardiomyopathy progression. Am J Nephrol 2011; 34:256-67. [PMID: 21791922 DOI: 10.1159/000330188] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
BACKGROUND/AIMS Angiotensin-converting enzyme (ACE) inhibitors have cardioprotective properties and functional calcium-sensing receptors express in cardiac myocytes. METHODS Rats were made uremic by 5/6 nephrectomy and treated as follows: uremic rats were fed on a regular diet (UC), uremic + enalapril (E), uremic + calcimimetic agent R-568 (R-568), and uremic + enalapril + R-568 (E+R-568). A group of normal rats served as controls (NC). RESULTS Blood pressure (BP) and left ventricle mass were elevated significantly in the UC and R-568 groups compared with those in the NC group, but were indistinguishable from normal controls in the E and E+R-568 groups. Cardiac fibrosis was significantly increased in the UC group compared with that in the NC group. This increase was significantly attenuated in the R-568 and E groups, and the attenuation was further enhanced in the E+R-568 group. Factors associated with cardiac hypertrophy such as proliferating cell nuclear antigen, cyclin D1, and cyclin D2, as well as factors associated with cardiac fibrosis such as type I collagen, fibronectin, and transforming growth factor-β1 were significantly increased in the UC group compared with those in the NC group. Monotherapy with R-568 or E attenuated this increase and the combination further attenuated these measures. CONCLUSIONS Calcimimetics can suppress the progression of uremic cardiomyopathy and this effect is amplified when BP is controlled via renin-angiotensin system blockade.
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Affiliation(s)
- Masahide Mizobuchi
- Division of Nephrology, Department of Medicine, Showa University School of Medicine, Tokyo, Japan.
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Brown EM. Clinical utility of calcimimetics targeting the extracellular calcium-sensing receptor (CaSR). Biochem Pharmacol 2010; 80:297-307. [PMID: 20382129 DOI: 10.1016/j.bcp.2010.04.002] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2010] [Revised: 03/31/2010] [Accepted: 04/01/2010] [Indexed: 02/03/2023]
Abstract
Calcimimetics, which activate the extracellular calcium (Ca(o)(2+))-sensing receptor in the parathyroid and other tissues participating in Ca(o)(2+) homeostasis, were the first described allosteric activators of a G-protein-coupled receptor. Cinacalcet, the only calcimimetic currently approved for human use, is used clinically for treating secondary hyperparathyroidism (e.g., overactivity of parathyroid glands) in patients being dialyzed for chronic kidney disease. By sensitizing the parathyroids to Ca(o)(2+), cinacalcet lowers the circulating parathyroid hormone (PTH) level. It also reduces serum calcium and phosphate, changes increasing the percentage of patients achieving the guidelines recommended by the National Kidney Foundation (NKF) for these minerals. Studies are underway addressing whether better adherence to these guidelines in patients receiving cinacalcet reduces cardiovascular disease and related mortality, which are both common is the dialysis population. The second approved use of cinacalcet is for treating hypercalcemia in patients with inoperable parathyroid carcinoma. In this setting, it provides the first medical therapy chronically lowering serum calcium concentration in this condition, albeit not to normal in most patients. Its effect on the long-term prognosis of these patients, if any, is presently unclear. "Off-label" administration of cinacalcet [i.e., not yet approved by the US Food and Drug Administration (FDA)] effectively lowers serum calcium and/or PTH in various other forms of hyperparathyroidism and increases serum phosphate in renal phosphate-wasting syndromes by reducing PTH-induced phosphaturia. In the future, the drug could conceivably be utilized to modulate the activity of the CaSR in other tissues (i.e., kidney, colon) in therapeutically desirable ways.
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Affiliation(s)
- Edward M Brown
- Division of Endocrinology, Diabetes and Hypertension, Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, EBRC 223A, 221 Longwood Ave, Boston, MA 02115, United States.
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Riccardi D, Brown EM. Physiology and pathophysiology of the calcium-sensing receptor in the kidney. Am J Physiol Renal Physiol 2010; 298:F485-99. [PMID: 19923405 PMCID: PMC2838589 DOI: 10.1152/ajprenal.00608.2009] [Citation(s) in RCA: 227] [Impact Index Per Article: 16.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2009] [Accepted: 11/13/2009] [Indexed: 12/21/2022] Open
Abstract
The extracellular calcium-sensing receptor (CaSR) plays a major role in the maintenance of a physiological serum ionized calcium (Ca2+) concentration by regulating the circulating levels of parathyroid hormone. It was molecularly identified in 1993 by Brown et al. in the laboratory of Dr. Steven Hebert with an expression cloning strategy. Subsequent studies have demonstrated that the CaSR is highly expressed in the kidney, where it is capable of integrating signals deriving from the tubular fluid and/or the interstitial plasma. Additional studies elucidating inherited and acquired mutations in the CaSR gene, the existence of activating and inactivating autoantibodies, and genetic polymorphisms of the CaSR have greatly enhanced our understanding of the role of the CaSR in mineral ion metabolism. Allosteric modulators of the CaSR are the first drugs in their class to become available for clinical use and have been shown to treat successfully hyperparathyroidism secondary to advanced renal failure. In addition, preclinical and clinical studies suggest the possibility of using such compounds in various forms of hypercalcemic hyperparathyroidism, such as primary and lithium-induced hyperparathyroidism and that occurring after renal transplantation. This review addresses the role of the CaSR in kidney physiology and pathophysiology as well as current and in-the-pipeline treatments utilizing CaSR-based therapeutics.
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Affiliation(s)
- Daniela Riccardi
- School of Biosciences, Cardiff University, Cardiff, United Kingdom.
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