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Urolithiasis as an extraarticular manifestation of ankylosing spondylitis. Rheumatol Int 2017; 37:1949-1956. [DOI: 10.1007/s00296-017-3788-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2017] [Accepted: 08/07/2017] [Indexed: 12/17/2022]
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Caballero D, Li Y, Fetene J, Ponsetto J, Chen A, Zhu C, Braddock DT, Bergwitz C. Intraperitoneal pyrophosphate treatment reduces renal calcifications in Npt2a null mice. PLoS One 2017; 12:e0180098. [PMID: 28704395 PMCID: PMC5509111 DOI: 10.1371/journal.pone.0180098] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2017] [Accepted: 06/09/2017] [Indexed: 12/12/2022] Open
Abstract
Mutations in the proximal tubular sodium-dependent phosphate co-transporters NPT2a and NPT2c have been reported in patients with renal stone disease and nephrocalcinosis, however the relative contribution of genotype, dietary calcium and phosphate, and modifiers of mineralization such as pyrophosphate (PPi) to the formation of renal mineral deposits is unclear. In the present study, we used Npt2a-/- mice to model the renal calcifications observed in these disorders. We observed elevated urinary excretion of PPi in Npt2a-/- mice when compared to WT mice. Presence of two hypomorphic Extracellular nucleotide pyrophosphatase phosphodiesterase 1 (Enpp1asj/asj) alleles decreased urine PPi and worsened renal calcifications in Npt2a-/- mice. These studies suggest that PPi is a thus far unrecognized factor protecting Npt2a-/- mice from the development of renal mineral deposits. Consistent with this conclusion, we next showed that renal calcifications in these mice can be reduced by intraperitoneal administration of sodium pyrophosphate. If confirmed in humans, urine PPi could therefore be of interest for developing new strategies to prevent the nephrocalcinosis and nephrolithiasis seen in phosphaturic disorders.
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Affiliation(s)
- Daniel Caballero
- Department of Medicine, Section Endocrinology, Yale University School of Medicine, New Haven, CT, United States of America
| | - Yuwen Li
- Endocrine Unit, Massachusetts General Hospital and Harvard Medical School, Boston, United States of America
- Department of Pediatrics, The First Affiliated Hospital, Nanjing Medical University, Nanjing, Jiangsu Province, China
| | - Jonathan Fetene
- Department of Medicine, Section Endocrinology, Yale University School of Medicine, New Haven, CT, United States of America
| | - Julian Ponsetto
- Department of Medicine, Section Endocrinology, Yale University School of Medicine, New Haven, CT, United States of America
| | - Alyssa Chen
- Department of Medicine, Section Endocrinology, Yale University School of Medicine, New Haven, CT, United States of America
| | - Chuanlong Zhu
- Gastroenterology Unit, Massachusetts General Hospital and Harvard Medical School, Boston, United States of America
- Department of Infectious Diseases, The First Affiliated Hospital, Nanjing Medical University, Nanjing, Jiangsu Province, China
| | - Demetrios T. Braddock
- Department of Pathology, Yale University School of Medicine, New Haven, CT, United States of America
| | - Clemens Bergwitz
- Department of Medicine, Section Endocrinology, Yale University School of Medicine, New Haven, CT, United States of America
- * E-mail:
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Vasudevan V, Samson P, Smith AD, Okeke Z. The genetic framework for development of nephrolithiasis. Asian J Urol 2016; 4:18-26. [PMID: 29264202 PMCID: PMC5730897 DOI: 10.1016/j.ajur.2016.11.003] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2016] [Accepted: 07/12/2016] [Indexed: 11/24/2022] Open
Abstract
Over 1%–15% of the population worldwide is affected by nephrolithiasis, which remains the most common and costly disease that urologists manage today. Identification of at-risk individuals remains a theoretical and technological challenge. The search for monogenic causes of stone disease has been largely unfruitful and a technological challenge; however, several candidate genes have been implicated in the development of nephrolithiasis. In this review, we will review current data on the genetic inheritance of stone disease, as well as investigate the evolving role of genetic analysis and counseling in the management of nephrolithiasis.
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Affiliation(s)
- Vinaya Vasudevan
- Smith Institute for Urology, Hofstra Northwell School of Medicine, Lake Success, NY, USA
| | - Patrick Samson
- Smith Institute for Urology, Hofstra Northwell School of Medicine, Lake Success, NY, USA
| | - Arthur D Smith
- Smith Institute for Urology, Hofstra Northwell School of Medicine, Lake Success, NY, USA
| | - Zeph Okeke
- Smith Institute for Urology, Hofstra Northwell School of Medicine, Lake Success, NY, USA
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Sadr-Eshkevari P, Ashnagar S, Rashad A, Dietz M, Jackowski J, Abdulazim A, Prochnow N. Bisphosphonates and connexin 43: a critical review of evidence. ACTA ACUST UNITED AC 2014; 21:241-7. [PMID: 24946183 DOI: 10.3109/15419061.2014.927869] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Bisphosphonates (BPs) are drugs commonly used in the treatment of various disease arising or affecting bone tissue. There is a standard use in bone neoplasia and metastasis, hormonal and developmental disorders as well as for compensation of adverse effects in several medical therapies. Many in-vivo and in-vitro studies have assessed the efficacy of this drug and its function in cellular scale. In this concern, BPs are described to inhibit the resorptive function of osteoclasts and to prevent apoptosis of osteoblasts and osteocytes. They can preserve the osteocytic network, reduce fracture rate, and increase the bone mineral content, which is therapeutically used. Connexin 43 (Cx43) is a crucial molecule for basal regulation of bone homeostasis, development, and differentiation. It is described for signal transduction in many physiological and pathological stimuli and recently to be involved in BP action.
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Abstract
Human and mouse alkaline phosphatases (AP) are encoded by a multigene family expressed ubiquitously in multiple tissues. Gene knockout (KO) findings have helped define some of the precise exocytic functions of individual isozymes in bone, teeth, the central nervous system, and in the gut. For instance, deficiency in tissue-nonspecific alkaline phosphatase (TNAP) in mice (Alpl (-/-) mice) and humans leads to hypophosphatasia (HPP), an inborn error of metabolism characterized by epileptic seizures in the most severe cases, caused by abnormal metabolism of pyridoxal-5'-phosphate (the predominant form of vitamin B6) and by hypomineralization of the skeleton and teeth featuring rickets and early loss of teeth in children or osteomalacia and dental problems in adults caused by accumulation of inorganic pyrophosphate (PPi). Enzyme replacement therapy with mineral-targeting TNAP prevented all the manifestations of HPP in mice, and clinical trials with this protein therapeutic are showing promising results in rescuing life-threatening HPP in infants. Conversely, TNAP induction in the vasculature during generalized arterial calcification of infancy (GACI), type II diabetes, obesity, and aging can cause medial vascular calcification. TNAP inhibitors, discussed extensively in this book, are in development to prevent pathological arterial calcification. The brush border enzyme intestinal alkaline phosphatase (IAP) plays an important role in fatty acid (FA) absorption, in protecting gut barrier function, and in determining the composition of the gut microbiota via its ability to dephosphorylate lipopolysaccharide (LPS). Knockout mice (Akp3 (-/-)) deficient in duodenal-specific IAP (dIAP) become obese, and develop hyperlipidemia and hepatic steatosis when fed a high-fat diet (HFD). These changes are accompanied by upregulation in the jejunal-ileal expression of the Akp6 IAP isozyme (global IAP, or gIAP) and concomitant upregulation of FAT/CD36, a phosphorylated fatty acid translocase thought to play a role in facilitating the transport of long-chain fatty acids into cells. gIAP, but not dIAP, is able to modulate the phosphorylation status of FAT/CD36. dIAP, even though it is expressed in the duodenum, is shed into the gut lumen and is active in LPS dephosphorylation throughout the gut lumen and in the feces. Akp3 (-/-) mice display gut dysbiosis and are more prone to dextran sodium sulfate-induced colitis than wild-type mice. Of relevance, oral administration of recombinant calf IAP prevents the dysbiosis and protects the gut from chronic colitis. Analogous to the role of IAP in the gut, TNAP expression in the liver may have a proactive role from bacterial endotoxin insult. Finally, more recent studies suggest that neuronal death in Alzheimer's disease may also be associated with TNAP function on certain brain-specific phosphoproteins. This review recounts the established roles of TNAP and IAP and briefly discusses new areas of investigation related to multisystemic functions of these isozymes.
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Naljayan M, Kumar S, Steinman T, Reisin E. Hypomagnesemia and hypokalemia: a successful oral therapeutic approach after 16 years of potassium and magnesium intravenous replacement therapy. Clin Kidney J 2014; 7:214-6. [PMID: 25852875 PMCID: PMC4377789 DOI: 10.1093/ckj/sfu014] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Key Words] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2013] [Accepted: 02/11/2014] [Indexed: 11/25/2022] Open
Affiliation(s)
- Mihran Naljayan
- Division of Nephrology and Hypertension, Department of Medicine , Louisiana State University Health Sciences Center , New Orleans, LA , USA
| | - Suresh Kumar
- Division of Nephrology and Hypertension , Louisiana State University Health Sciences Center , New Orleans, LA , USA
| | - Theodore Steinman
- Harvard Medical School , Beth Israel Deaconess Medical Center , Boston, MA , USA
| | - Efrain Reisin
- Division of Nephrology and Hypertension , Louisiana State University Health Sciences Center , New Orleans, LA , USA
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Moochhala SH. Extracellular pyrophosphate in the kidney: how does it get there and what does it do? Nephron Clin Pract 2012; 120:p33-8. [PMID: 23075758 PMCID: PMC5166521 DOI: 10.1159/000341597] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Pyrophosphate (PPi) is well known as a regulator of calcification, and the ANKH (ANK in mouse) protein has a role in the membrane transport of PPi. Earlier work concentrated on bones and joints, but ANKH is also likely to have important roles in the kidney, with newer studies focusing on vascular calcification in renal failure. Renal calcification can occur due to a naturally occurring ANK mouse mutation, yet other ANK mutations do not cause a renal phenotype. Despite evidence over 10 years of ANKH's involvement in PPi transport, efflux of PPi via ANKH has never been demonstrated. Rather than physically moving PPi, the ANKH protein may assist its membrane transport in other ways such as by hydrolysis and compartmentalisation. Protein complexes may account for effects of ANKH that are specific to particular tissues. In the kidney, recent localisation data may be helpful in suggesting physiological roles for ANKH, such as its co-localisation with aquaporin-2 and cilial proteins. Such diverse functions would reflect the ubiquitous nature of ANKH in tissues and its profound evolutionary conservation.
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Affiliation(s)
- Shabbir H Moochhala
- UCL Centre for Nephrology Royal Free, Royal Free London NHS Foundation Trust, London, UK. smoochhala @ nhs.net
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KORKMAZ CENGIZ, SAYER JOHNA. ANKH and Renal Stone Formation in Ankylosing Spondylitis. J Rheumatol 2012; 39:1756; author reply 1757. [DOI: 10.3899/jrheum.120161] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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Lezcano V, Bellido T, LI P, Boland R, Morelli S. Role of connexin 43 in the mechanism of action of alendronate: dissociation of anti-apoptotic and proliferative signaling pathways. Arch Biochem Biophys 2012; 518:95-102. [PMID: 22230328 PMCID: PMC3804299 DOI: 10.1016/j.abb.2011.12.022] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2011] [Revised: 12/21/2011] [Accepted: 12/23/2011] [Indexed: 11/28/2022]
Abstract
Bisphosphonates (BPs) inhibit osteocyte and osteoblast apoptosis via opening of connexin (Cx) 43 hemichannels and activating the extracellular signal regulated kinases ERKs. Previously, we hypothesized that intracellular survival signaling is initiated by interaction of BPs with Cx43. However, using whole cell binding assays with [(3)H]-alendronate, herein we demonstrated the presence of saturable, specific and high affinity binding sites in the Cx43-expressing ROS 17/2.8 osteoblastic cells, authentic osteoblasts and MLO-Y4 cells expressing Cx43 or not, as well as in HeLa cells lacking Cx43 expression and ROS 17/2.8 cells pretreated with agents that disassemble Cx channels. In addition, both BPs and the PTP inhibitor Na(3)VO(4) increased proliferation of cells expressing Cx43 or not. Furthermore, although BPs are internalized and inhibit intracellular enzymes in osteoclasts, whether the drugs penetrate non-resorptive bone cells is not known. To clarify this, we evaluated the osteoblastic uptake of AF-ALN, a fluorescently labeled analog of alendronate. AF-ALN was rapidly internalized in cells expressing Cx43 or not indicating that this process is not mediated via Cx43 hemichannels. Altogether, these findings suggest that although required for triggering intracellular survival signaling by BPs, Cx43 is dispensable for cellular BP binding, its uptake, as well as the proliferative effects of these agents.
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Affiliation(s)
- V Lezcano
- Departamento de Biología, Bioquímica y Farmacia, Universidad Nacional del Sur, Bahía Blanca, Argentina
| | - T Bellido
- Department of Anatomy and Cell Biology, Indiana University School of Medicine. Indianapolis, Indiana, USA
- Division of Endocrinology, Department of Internal Medicine, Indiana University School of Medicine. Indianapolis, Indiana, USA
| | - Plotkin LI
- Department of Anatomy and Cell Biology, Indiana University School of Medicine. Indianapolis, Indiana, USA
| | - R Boland
- Departamento de Biología, Bioquímica y Farmacia, Universidad Nacional del Sur, Bahía Blanca, Argentina
| | - S Morelli
- Departamento de Biología, Bioquímica y Farmacia, Universidad Nacional del Sur, Bahía Blanca, Argentina
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The Genetics of Kidney Stones. Urolithiasis 2012. [DOI: 10.1007/978-1-4471-4387-1_16] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Morava E, Kühnisch J, Drijvers JM, Robben JH, Cremers C, van Setten P, Branten A, Stumpp S, de Jong A, Voesenek K, Vermeer S, Heister A, Claahsen-van der Grinten HL, O'Neill CW, Willemsen MA, Lefeber D, Deen PMT, Kornak U, Kremer H, Wevers RA. Autosomal recessive mental retardation, deafness, ankylosis, and mild hypophosphatemia associated with a novel ANKH mutation in a consanguineous family. J Clin Endocrinol Metab 2011; 96:E189-98. [PMID: 20943778 PMCID: PMC5393418 DOI: 10.1210/jc.2010-1539] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
CONTEXT Mutations in ANKH cause the highly divergent conditions familial chondrocalcinosis and craniometaphyseal dysplasia. The gene product ANK is supposed to regulate tissue mineralization by transporting pyrophosphate to the extracellular space. OBJECTIVE We evaluated several family members of a large consanguineous family with mental retardation, deafness, and ankylosis. We compared their skeletal, metabolic, and serological parameters to that of the autosomal recessive progressive ankylosis (ank) mouse mutant, caused by a loss-of-function mutation in the murine ortholog Ank. PARTICIPANTS The studied patients had painful small joint soft-tissue calcifications, progressive spondylarthropathy, osteopenia, mild hypophosphatemia, mixed hearing loss, and mental retardation. RESULTS After mapping the disease gene to 5p15, we identified the novel homozygous ANK missense mutation L244S in all patients. Although L244 is a highly conserved amino acid, the mutated ANK protein was detected at normal levels at the plasma membrane in primary patient fibroblasts. The phenotype was highly congruent with the autosomal recessive progressive ankylosis (ank) mouse mutant. This indicates a loss-of-function effect of the L244S mutation despite normal ANK protein expression. Interestingly, our analyses revealed that the primary step of joint degeneration is fibrosis and mineralization of articular soft tissues. Moreover, heterozygous carriers of the L244S mutation showed mild osteoarthritis without metabolic alterations, pathological calcifications, or central nervous system involvement. CONCLUSION Beyond the description of the first human progressive ankylosis phenotype, our results indicate that ANK influences articular soft tissues commonly involved in degenerative joint disorders. Furthermore, this human disorder provides the first direct evidence for a role of ANK in the central nervous system.
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Affiliation(s)
- Eva Morava
- Radboud University Nijmegen, Department of Pediatrics, Nijmegen, The Netherlands.
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Graziani G, Fedeli C, Moroni L, Cosmai L, Badalamenti S, Ponticelli C. Gitelman syndrome: pathophysiological and clinical aspects. QJM 2010; 103:741-8. [PMID: 20650971 DOI: 10.1093/qjmed/hcq123] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Giltelman syndrome (GS) is a recessive salt-losing tubulopathy of children or young adults caused by a mutation of genes encoding the human sodium chloride cotransporters and magnesium channels in the thiazide-sensitive segments of the distal convoluted tubule. The plasma biochemical picture is characterized by hypokalemia, hypomagnesemia, hypocalciuria, metabolic alkalosis and hypereninemic hyperaldosteronism. However, patients with GS present some clinical and biochemical alterations resembling that observed in thiazide diuretics abuse. On the pathophysiological point of view, GS represents a useful and interesting human model to better understand the clinical consequences of plasma hydro-electrolytes and acid-base derangements, associated with multiple hormonal alterations. The impact of this complex disorder involves cardiovascular, muscle-skeletal and some other physiological functions, adversely affecting the patient's quality of life. This review tries to summarize and better explain the linkage between the electrolytes, neurohormonal derangements and clinical picture. Moreover, the differential diagnosis between other similar electrolyte-induced clinical disorders and GS is also discussed.
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Affiliation(s)
- G Graziani
- Nephrology and Dialysis Unit, IRCCS Istituto Clinico Humanitas, Rozzano, Milano, Italy.
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Zajac A, Baek SH, Salhab I, Radecki MA, Kim S, Hakonarson H, Nah HD. Novel ANKH mutation in a patient with sporadic craniometaphyseal dysplasia. Am J Med Genet A 2010; 152A:770-6. [PMID: 20186813 DOI: 10.1002/ajmg.a.33317] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Craniometaphyseal dysplasia is caused by mutations in ANKH (ankylosis, progressive homolog [mouse]) in the majority of cases, and all of the reported mutations are single amino acid changes. Genomic DNA from an affected patient, his biological parents, and a sibling was amplified and ANKH was sequenced. The affected patient had a complex heterozygous mutation in exon 7 (c.936T > C, c.938C > G, c.942_953delTGGTTGACGGAA), predicting p.Try290Gln and p.Trp292_Glu295del. We studied the effect of the predicted mutation on the subcellular distribution of ANKH protein. Immunofluorescent labeling of COS-7 cells transduced with normal or mutant Ank (murine progressive ankylosis), showed that normal Ank localized to both the plasma membrane and cytoplasm, whereas mutant Ank was detected only in the cytoplasmic compartment. We propose that this craniometaphyseal dysplasia mutation causes a loss of ANKH protein expression and activity in the plasma membrane as a result of aberrant intracellular protein trafficking.
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Affiliation(s)
- Allison Zajac
- Division of Plastic and Reconstructive Surgery, The Children's Hospital of Philadelphia, Philadelphia, Pennsylvania 19104, USA
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Abstract
Craniometaphyseal dysplasia (CMD) is a monogenic human disorder characterized by thickening of craniofacial bones and flaring metaphyses of long bones. Mutations for autosomal dominant CMD have been identified in the progressive ankylosis gene ANKH. Previous studies of Ank loss-of-function models, Ank(null/null) and Ank(ank/ank) mice, suggest that Ank plays a role in the regulation of bone mineralization. However, the mechanism for Ank mutations leading to CMD remains unknown. We generated the first knockin (KI) mouse model for CMD expressing a human mutation (Phe377 deletion) in ANK. Homozygous Ank knockin mice (Ank(KI/KI)) replicate many typical features of human CMD including hyperostosis of craniofacial bones, massive jawbones, decreased diameters of cranial foramina, obliteration of nasal sinuses, fusion of middle ear bones, and club-shaped femurs. In addition, Ank(KI/KI) mice have increased serum alkaline phosphatase and TRACP5b, as reported in CMD patients. Biochemical markers of bone formation and bone resorption, N-terminal propeptide of type I procollagen and type I collagen cross-linked C-terminal telopeptide, are significantly increased in Ank(KI/KI) mice, suggesting increased bone turnover. Interestingly, Ank(KI/KI) bone marrow-derived macrophage cultures show decreased osteoclastogenesis. Despite the hyperostotic phenotype, bone matrix in Ank(KI/KI) mice is hypomineralized and less mature, indicating that biomechanical properties of bones may be compromised by the Ank mutation. We believe this new mouse model will facilitate studies of skeletal abnormalities in CMD at cellular and molecular levels.
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Moochhala SH, Sayer JA, Carr G, Simmons NL. Renal calcium stones: insights from the control of bone mineralization. Exp Physiol 2007; 93:43-9. [PMID: 17911353 DOI: 10.1113/expphysiol.2007.040790] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Extracellular pyrophosphate (PPi) plays a central role in the control of normal bone mineralization since it antagonizes inorganic phosphate in the promotion of hydroxyapatite deposition. Studies using knock-out mice have established the functional importance of PPi generation via nucleotide pyrophosphatase phosphodiesterases (NPP) and of PPi transmembrane transport by the progressive ankylosis (ANK) protein. Tissue non-specific alkaline phosphatase activity counteracts this by hydrolysis of PPi to inorganic phosphate. The molecular nature and transport function of ANK are reviewed. A close parallel is drawn between the controlled mineralization of bone and the prevention of abnormal calcium crystal deposition within the kidney, especially when concentrated urine is produced. Pyrophosphate is present in urine, and ANK is expressed in the cortical collecting duct where PPi transport to both the tubular lumen and the renal interstitium may occur. Pyrophosphate may also be generated here by nucleoside triphosphate diphosphohydrolases (NTPD2 and 3) together with NPP1. Alkaline phosphatase activity is restricted to the proximal nephron, remote from these sites of PPi generation, transport and function. The physiological importance of PPi generation and transport in preventing idiopathic calcium renal stone disease and nephrocalcinosis now needs to be established.
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Affiliation(s)
- S H Moochhala
- Epithelial Research Group, Institute for Cell and Molecular Biosciences, Medical School, Framlington Place, University of Newcastle upon Tyne, Newcastle upon Tyne NE2 4HH, UK
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