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Gędaj A, Gregorczyk P, Żukowska D, Chorążewska A, Ciura K, Kalka M, Porębska N, Opaliński Ł. Glycosylation of FGF/FGFR: An underrated sweet code regulating cellular signaling programs. Cytokine Growth Factor Rev 2024; 77:39-55. [PMID: 38719671 DOI: 10.1016/j.cytogfr.2024.04.001] [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: 03/21/2024] [Revised: 04/23/2024] [Accepted: 04/23/2024] [Indexed: 06/22/2024]
Abstract
Fibroblast growth factors (FGFs) and their receptors (FGFRs) constitute plasma-membrane localized signaling hubs that transmit signals from the extracellular environment to the cell interior, governing pivotal cellular processes like motility, metabolism, differentiation, division and death. FGF/FGFR signaling is critical for human body development and homeostasis; dysregulation of FGF/FGFR units is observed in numerous developmental diseases and in about 10% of human cancers. Glycosylation is a highly abundant posttranslational modification that is critical for physiological and pathological functions of the cell. Glycosylation is also very common within FGF/FGFR signaling hubs. Vast majority of FGFs (15 out of 22 members) are N-glycosylated and few FGFs are O-glycosylated. Glycosylation is even more abundant within FGFRs; all FGFRs are heavily N-glycosylated in numerous positions within their extracellular domains. A growing number of studies points on the multiple roles of glycosylation in fine-tuning FGF/FGFR signaling. Glycosylation modifies secretion of FGFs, determines their stability and affects interaction with FGFRs and co-receptors. Glycosylation of FGFRs determines their intracellular sorting, constitutes autoinhibitory mechanism within FGFRs and adjusts FGF and co-receptor recognition. Sugar chains attached to FGFs and FGFRs constitute also a form of code that is differentially decrypted by extracellular lectins, galectins, which transform FGF/FGFR signaling at multiple levels. This review focuses on the identified functions of glycosylation within FGFs and FGFRs and discusses their relevance for the cell physiology in health and disease.
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Affiliation(s)
- Aleksandra Gędaj
- Department of Protein Engineering, Faculty of Biotechnology, University of Wroclaw, Joliot-Curie 14a, Wroclaw 50-383, Poland
| | - Paulina Gregorczyk
- Department of Protein Engineering, Faculty of Biotechnology, University of Wroclaw, Joliot-Curie 14a, Wroclaw 50-383, Poland
| | - Dominika Żukowska
- Department of Protein Engineering, Faculty of Biotechnology, University of Wroclaw, Joliot-Curie 14a, Wroclaw 50-383, Poland
| | - Aleksandra Chorążewska
- Department of Protein Engineering, Faculty of Biotechnology, University of Wroclaw, Joliot-Curie 14a, Wroclaw 50-383, Poland
| | - Krzysztof Ciura
- Department of Protein Engineering, Faculty of Biotechnology, University of Wroclaw, Joliot-Curie 14a, Wroclaw 50-383, Poland
| | - Marta Kalka
- Department of Protein Engineering, Faculty of Biotechnology, University of Wroclaw, Joliot-Curie 14a, Wroclaw 50-383, Poland
| | - Natalia Porębska
- Department of Protein Engineering, Faculty of Biotechnology, University of Wroclaw, Joliot-Curie 14a, Wroclaw 50-383, Poland
| | - Łukasz Opaliński
- Department of Protein Engineering, Faculty of Biotechnology, University of Wroclaw, Joliot-Curie 14a, Wroclaw 50-383, Poland.
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Jiang Q, Qin X, Moriishi T, Fukuyama R, Katsumata S, Matsuzaki H, Komori H, Matsuo Y, Sakane C, Ito K, Hojo H, Ohba S, Komori T. Runx2 Regulates Galnt3 and Fgf23 Expressions and Galnt3 Decelerates Osteoid Mineralization by Stabilizing Fgf23. Int J Mol Sci 2024; 25:2275. [PMID: 38396954 PMCID: PMC10889289 DOI: 10.3390/ijms25042275] [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: 12/30/2023] [Revised: 01/31/2024] [Accepted: 02/05/2024] [Indexed: 02/25/2024] Open
Abstract
Runx2 (runt related transcription factor 2) is an essential transcription factor for osteoblast proliferation and differentiation. Uridine diphosphate (UDP)-N-acetylgalactosamine (GalNAc): polypeptide GalNAc-transferase 3 (Galnt3) prevents proteolytic processing of fibroblast growth factor 23 (Fgf23), which is a hormone that regulates the serum level of phosphorus. Runx2 and Galnt3 were expressed in osteoblasts and osteocytes, and Fgf23 expression was restricted to osteocytes in bone. Overexpression and knock-down of Runx2 upregulated and downregulated, respectively, the expressions of Galnt3 and Fgf23, and Runx2 directly regulated the transcriptional activity of Galnt3 in reporter assays. The expressions of Galnt3 and Fgf23 in osteoblast-specific Runx2 knockout (Runx2fl/flCre) mice were about half those in Runx2fl/fl mice. However, the serum levels of phosphorus and intact Fgf23 in Runx2fl/flCre mice were similar to those in Runx2fl/fl mice. The trabecular bone volume was increased during aging in both male and female Galnt3-/- mice, but the osteoid was reduced. The markers for bone formation and resorption in Galnt3-/- mice were similar to the control in both sexes. Galnt3-/- mice exhibited hyperphosphatemia and hypercalcemia, and the intact Fgf23 was about 40% that of wild-type mice. These findings indicated that Runx2 regulates the expressions of Galnt3 and Fgf23 and that Galnt3 decelerates the mineralization of osteoid by stabilizing Fgf23.
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Affiliation(s)
- Qing Jiang
- Institute of Orthopaedics, Suzhou Medical College, Soochow University, Suzhou 215006, China
- Department of Molecular Bone Biology, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki 852-8588, Japan
| | - Xin Qin
- Institute of Orthopaedics, Suzhou Medical College, Soochow University, Suzhou 215006, China
- Department of Molecular Bone Biology, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki 852-8588, Japan
| | - Takeshi Moriishi
- Department of Cell Biology, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki 852-8588, Japan
| | - Ryo Fukuyama
- Laboratory of Pharmacology, Hiroshima International University, Kure 737-0112, Japan
| | - Shinichi Katsumata
- Department of Nutritional Science, Faculty of Applied Bioscience, Tokyo University of Agriculture, Tokyo 156-8502, Japan
| | - Hiroshi Matsuzaki
- Department of Nutritional Science, Faculty of Applied Bioscience, Tokyo University of Agriculture, Tokyo 156-8502, Japan
| | - Hisato Komori
- Department of Molecular Bone Biology, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki 852-8588, Japan
| | - Yuki Matsuo
- Department of Molecular Bone Biology, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki 852-8588, Japan
- Department of Cell Biology, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki 852-8588, Japan
| | - Chiharu Sakane
- Research Center for Biomedical Models and Animal Welfare, Nagasaki University, Nagasaki 852-8523, Japan
| | - Kosei Ito
- Department of Molecular Bone Biology, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki 852-8588, Japan
| | - Hironori Hojo
- Laboratory of Clinical Biotechnology, Center for Disease Biology and Integrative Medicine, Graduate School of Medicine, The University of Tokyo, Tokyo 113-8655, Japan
| | - Shinsuke Ohba
- Department of Tissue and Developmental Biology, Graduate School of Dentistry, Osaka University, Osaka 565-0871, Japan
| | - Toshihisa Komori
- Department of Molecular Bone Biology, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki 852-8588, Japan
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Clinkenbeard E. Fibroblast Growth Factor 23 Bone Regulation and Downstream Hormonal Activity. Calcif Tissue Int 2023; 113:4-20. [PMID: 37306735 DOI: 10.1007/s00223-023-01092-1] [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: 03/05/2023] [Accepted: 05/01/2023] [Indexed: 06/13/2023]
Abstract
Mineral homeostasis of calcium and phosphate levels is one critical component to the maintenance of bone mineral density (BMD) and strength. Diseases that disrupt calcium and phosphate balanced have highlighted not only the role these minerals play in overall bone homeostasis, but also the factors, hormones and downstream transporters, responsible for mineral metabolism. The key phosphaturic hormone elucidated from studying rare heritable disorders of hypophosphatemia is Fibroblast Growth Factor 23 (FGF23). FGF23 is predominantly secreted from bone cells in an effort to maintain phosphate balance by directly controlling renal reabsorption and indirectly affecting intestinal uptake of this mineral. Multiple factors have been shown to enhance bone mRNA expression; however, FGF23 can also undergo proteolytic cleavage to control secretion of the biologically active form of the hormone. The review focuses specifically on the regulation of FGF23 and its secretion from bone as well as its hormonal actions under physiological and disease conditions.
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Affiliation(s)
- Erica Clinkenbeard
- Department of Medical and Molecular Genetics, School of Medicine, Indiana University, 635 Barnhill Drive MS 5023, Indianapolis, IN, 46202, USA.
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Kritmetapak K, Kumar R. Phosphatonins: From Discovery to Therapeutics. Endocr Pract 2023; 29:69-79. [PMID: 36210014 DOI: 10.1016/j.eprac.2022.09.007] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/22/2022] [Revised: 09/22/2022] [Accepted: 09/23/2022] [Indexed: 01/11/2023]
Abstract
OBJECTIVE Phosphate is crucial for cell signaling, energy metabolism, nucleotide synthesis, and bone mineralization. The gut-bone-parathyroid-kidney axis is influenced by parathyroid hormone, 1,25-dihydroxyvitamin D, and phosphatonins, especially fibroblast growth factor 23 (FGF23). These hormones facilitate maintenance of phosphate homeostasis. This review summarizes current knowledge regarding the phosphate homeostasis, phosphatonin pathophysiology, and clinical implications of FGF23-related hypophosphatemic disorders, with specific focus on burosumab treatment. METHOD A focused literature search of PubMed was conducted. RESULTS Phosphatonins including FGF23, secreted frizzled-related protein 4, matrix extracellular phosphoglycoprotein, and fibroblast growth factor 7 play a pathogenic role in several hypophosphatemic disorders. Excess FGF23 inhibits sodium-dependent phosphate cotransporters (NaPi-2a and NaPi-2c), resulting in hyperphosphaturia and hypophosphatemia. Additionally, FGF23 suppresses 1,25-dihydroxyvitamin D synthesis in the proximal renal tubule, and thus, it indirectly inhibits intestinal phosphate absorption. Disorders of FGF23-related hypophosphatemia include X-linked hypophosphatemia (XLH), autosomal dominant hypophosphatemic rickets, autosomal recessive hypophosphatemic rickets, fibrous dysplasia/McCune-Albright syndrome, and tumor-induced osteomalacia (TIO). Complications of conventional therapy with oral phosphate and vitamin D analogs comprise gastrointestinal distress, hypercalcemia, nephrocalcinosis, and secondary/tertiary hyperparathyroidism. In both children and adults with XLH and TIO, the anti-FGF23 antibody burosumab exhibits a favorable safety profile and is associated with healing of rickets in affected children and improvement of osteomalacia in both children and adults. CONCLUSION The treatment paradigm for XLH and TIO is changing based on data from recent clinical trials. Research suggest that burosumab is effective and safe for pediatric and adult patients with XLH or TIO.
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Affiliation(s)
| | - Rajiv Kumar
- Division of Nephrology and Hypertension, Mayo Clinic, Rochester, Minnesota.
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Guo L, Wang Y, Li S, Zhou L, Li D. GALNT3 protects against phosphate-induced calcification in vascular smooth muscle cells by enhancing active FGF23 and inhibiting the wnt/β-catenin signaling pathway. Cell Signal 2022; 100:110477. [PMID: 36162588 DOI: 10.1016/j.cellsig.2022.110477] [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: 07/30/2022] [Revised: 09/12/2022] [Accepted: 09/20/2022] [Indexed: 11/03/2022]
Abstract
Vascular calcification (VC) acts as a notable risk factor in the cardiovascular system. Disorder of phosphorus (Pi) metabolism promotes VC. Recent findings show that polypeptide N-acetylgalactosaminyltransferase 3(GALNT3) is Pi responsive and with potent effects on Pi homeostasis. However, whether GALNT3 is involved in high Pi-induced VC remains unclear. The present study investigated the potential role of GALNT3 as a novel regulator of VC. In vitro, human aortic smooth muscle cells (HASMCs) calcification was induced by inorganic Pi, while in vivo, C57BL/6 J mice were used to determine the effects of GALNT3 on Vitamin D3-induced medial arterial calcification. Alizarin red staining, Von Kossa staining, calcium and alkaline phosphatase (ALP) activity were performed to test VC. We showed that expression of GALNT3 was increased in the calcified HASMCs and aortas of the calcified mice.In vitro, overexpression of GALNT3 increased the levels of active full-length FGF23, accompanied by suppression of the osteoblast-related factors (Runx2 and BMP2), and further inhibited the formation of calcified nodules. Moreover, the protein levels of Wnt3a and active β-catenin were determined and it was found that GALNT3 significantly inhibited their expression. LiCl, a Wnt/β-catenin signaling activator, was observed to reverse the protective effect of GALNT3 overexpression. The opposite results were observed in the GALNT3 knockdown cells. In vivo, overexpression of GALNT3 by adeno-associated virus decreased the serum Pi and slowed the formation of aortic calcification in the calcified mice. In conclusion, our results indicate that GALNT3 counteracts high Pi-induced osteoblastic differentiation of VSMCs and protects against the initiation and progression of VC by inhibiting the Wnt/β-catenin signaling pathway.
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Affiliation(s)
- Liwei Guo
- School of Forensic Medicine, Xinxiang Medical University, Xinxiang, Henan, China; Xinxiang Key Laboratory of Metabolism and Integrative Physiology, Xinxiang, Henan, China.
| | - Yikai Wang
- School of Forensic Medicine, Xinxiang Medical University, Xinxiang, Henan, China; Xinxiang Key Laboratory of Metabolism and Integrative Physiology, Xinxiang, Henan, China
| | - Shijie Li
- School of Forensic Medicine, Xinxiang Medical University, Xinxiang, Henan, China; Xinxiang Key Laboratory of Metabolism and Integrative Physiology, Xinxiang, Henan, China
| | - Lulu Zhou
- School of Forensic Medicine, Xinxiang Medical University, Xinxiang, Henan, China; Xinxiang Key Laboratory of Metabolism and Integrative Physiology, Xinxiang, Henan, China
| | - Duan Li
- School of Basic Medicine, Xinxiang Medical University, Xinxiang, Henan, China.
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Sharma S, Katz R, Ginsberg C, Bullen A, Vallon V, Thomson S, Moe OW, Hoofnagle AN, de Leeuw PW, Kroon AA, Houben AJHM, Ix JH. Renal Clearance of Fibroblast Growth Factor-23 (FGF23) and its Fragments in Humans. J Bone Miner Res 2022; 37:1170-1178. [PMID: 35373859 PMCID: PMC9177785 DOI: 10.1002/jbmr.4553] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/07/2021] [Revised: 03/08/2022] [Accepted: 03/28/2022] [Indexed: 11/06/2022]
Abstract
Relative abundance of fibroblast growth factor-23 (FGF23) measured by the C-terminal (cFGF23, which measures both intact FGF23 and C-terminal fragments) versus intact (iFGF23, measures only intact hormone) assays varies by kidney function in humans. Differential kidney clearance may explain this finding. We measured cFGF23 and iFGF23 in the aorta and bilateral renal veins of 162 patients with essential hypertension undergoing renal angiography. Using multivariable linear regression, we examined factors associated with aorta to renal vein reduction of FGF23 using both assays. Similar parameters and with addition of urine concentrations of cFGF23 and iFGF23 were measured in six Wistar rats. Mean ± standard deviation (SD) age was 54 ± 12 years, 54% were women, and mean creatinine clearance was 72 ± 48 mL/min/100 g. The human kidney reduced the concentrations of both cFGF23 (16% ± 12%) and iFGF23 (21% ± 16%), but reduction was higher for iFGF23. Greater kidney creatinine and PTH reductions were each independently associated with greater reductions of both cFGF23 and iFGF23. The greater kidney reduction of iFGF23 compared to cFGF23 appeared stable and consistent across the range of creatinine clearance evaluated. Kidney clearance was similar, and urine concentrations of both assays were low in the rat models, suggesting kidney metabolism of both cFGF23 and iFGF23. Renal reduction of iFGF23 is higher than that of creatinine and cFGF23. Our data suggest that FGF23 is metabolized by the kidney. However, the major cell types involved in metabolization of FGF23 requires future study. Kidney clearance of FGF23 does not explain differences in C-terminal and intact moieties across the range of kidney function. © 2022 American Society for Bone and Mineral Research (ASBMR).
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Affiliation(s)
- Shilpa Sharma
- Division of Nephrology, David Geffen School of Medicine at UCLA, Los Angeles, CA, USA.,Nephrology Section, Veterans Affairs Greater Los Angeles Healthcare System, Los Angeles, CA, USA
| | - Ronit Katz
- University of Washington, Seattle, WA, USA
| | - Charles Ginsberg
- Division of Nephrology-Hypertension, Department of Medicine, University of California San Diego, San Diego, CA, USA
| | - Alexander Bullen
- Division of Nephrology-Hypertension, Department of Medicine, University of California San Diego, San Diego, CA, USA.,Nephrology Section, Veterans Affairs San Diego Healthcare System, La Jolla, CA, USA
| | - Volker Vallon
- Division of Nephrology-Hypertension, Department of Medicine, University of California San Diego, San Diego, CA, USA.,Nephrology Section, Veterans Affairs San Diego Healthcare System, La Jolla, CA, USA.,Department of Pharmacology, University of California-San Diego, La Jolla, CA, USA
| | - Scott Thomson
- Division of Nephrology-Hypertension, Department of Medicine, University of California San Diego, San Diego, CA, USA.,Nephrology Section, Veterans Affairs San Diego Healthcare System, La Jolla, CA, USA.,Department of Pharmacology, University of California-San Diego, La Jolla, CA, USA
| | - Orson W Moe
- Charles and Jane Pak Center of Mineral Metabolism and Clinical Research, University of Texas Southwestern Medical Center, Dallas, TX, USA.,Departments of Internal Medicine and Physiology, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | | | - Peter W de Leeuw
- Department of Internal Medicine and CARIM School for Cardiovascular Diseases, Maastricht University Medical Centre, Maastricht, The Netherlands
| | - Abraham A Kroon
- Department of Internal Medicine and CARIM School for Cardiovascular Diseases, Maastricht University Medical Centre, Maastricht, The Netherlands
| | - Alfons J H M Houben
- Department of Internal Medicine and CARIM School for Cardiovascular Diseases, Maastricht University Medical Centre, Maastricht, The Netherlands
| | - Joachim H Ix
- Division of Nephrology-Hypertension, Department of Medicine, University of California San Diego, San Diego, CA, USA.,Nephrology Section, Veterans Affairs San Diego Healthcare System, La Jolla, CA, USA
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Npt2a as a target for treating hyperphosphatemia. Biochem Soc Trans 2022; 50:439-446. [PMID: 34994388 PMCID: PMC9022968 DOI: 10.1042/bst20211005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2021] [Revised: 12/08/2021] [Accepted: 12/13/2021] [Indexed: 12/04/2022]
Abstract
Hyperphosphatemia results from an imbalance in phosphate (Pi) homeostasis. In patients with and without reduced kidney function, hyperphosphatemia is associated with cardiovascular complications. The current mainstays in the management of hyperphosphatemia are oral Pi binder and dietary Pi restriction. Although these options are employed in patients with chronic kidney disease (CKD), they seem inadequate to correct elevated plasma Pi levels. In addition, a paradoxical increase in expression of intestinal Pi transporter and uptake may occur. Recently, studies in rodents targeting the renal Na+/Pi cotransporter 2a (Npt2a), responsible for ∼70% of Pi reabsorption, have been proposed as a potential treatment option. Two compounds (PF-06869206 and BAY-767) have been developed which are selective for Npt2a. These Npt2a inhibitors significantly increased urinary Pi excretion consequently lowering plasma Pi and PTH levels. Additionally, increases in urinary excretions of Na+, Cl− and Ca2+ have been observed. Some of these results are also seen in models of reduced kidney function. Responses of FGF23, a phosphaturic hormone that has been linked to the development of left ventricular hypertrophy in CKD, are ambiguous. In this review, we discuss the recent advances on the role of Npt2a inhibition on Pi homeostasis as well as other pleiotropic effects observed with Npt2a inhibition.
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Al Rifai O, Susan-Resiga D, Essalmani R, Creemers JWM, Seidah NG, Ferron M. In Vivo Analysis of the Contribution of Proprotein Convertases to the Processing of FGF23. Front Endocrinol (Lausanne) 2021; 12:690681. [PMID: 34149625 PMCID: PMC8213403 DOI: 10.3389/fendo.2021.690681] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/03/2021] [Accepted: 05/13/2021] [Indexed: 12/25/2022] Open
Abstract
Fibroblast growth factor 23 (FGF23) is a hormone secreted from fully differentiated osteoblasts and osteocytes that inhibits phosphate reabsorption by kidney proximal tubules. The full-length (i.e., intact) protein mediates FGF23 endocrine functions, while endoproteolytic cleavage at a consensus cleavage sequence for the proprotein convertases (PCs) inactivates FGF23. Two PCs, furin and PC5, were shown to cleave FGF23 in vitro at RHTR179↓, but whether they are fulfilling this function in vivo is currently unknown. To address this question, we used here mice lacking either or both furin and PC5 in cell-specific manners and mice lacking the paired basic amino acid-cleaving enzyme 4 (PACE4) in all cells. Our analysis shows that furin inactivation in osteoblasts and osteocytes results in a 25% increase in circulating intact FGF23, without any significant impact on serum phosphate levels, whether mice are maintained on a normal or a low phosphate diet. Under conditions of iron deficiency, FGF23 is normally processed in control mice, but its processing is impaired in mice lacking furin in osteoblasts and osteocytes. In contrast, FGF23 is normally cleaved following erythropoietin or IL-1β injections in mice lacking furin or both furin and PC5, and in PACE4-deficient mice. Altogether, these studies suggest that furin is only partially responsible for FGF23 cleavage under certain conditions in vivo. The processing of FGF23 may therefore involve the redundant action of multiple PCs or of other peptidases in osteoblasts, osteocytes and hematopoietic cells.
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Affiliation(s)
- Omar Al Rifai
- Unité de recherche en physiologie moléculaire, Institut de Recherches Cliniques de Montréal, Montréal, QC, Canada
- Programme de biologie moléculaire, Université de Montréal, Montréal, QC, Canada
| | - Delia Susan-Resiga
- Unité de recherche en biochimie neuroendocrinienne, Institut de Recherches Cliniques de Montréal, Montréal, QC, Canada
| | - Rachid Essalmani
- Unité de recherche en biochimie neuroendocrinienne, Institut de Recherches Cliniques de Montréal, Montréal, QC, Canada
| | - John W. M. Creemers
- Department of Human Genetics, Katholieke Universiteit (KU) Leuven, Leuven, Belgium
| | - Nabil G. Seidah
- Unité de recherche en biochimie neuroendocrinienne, Institut de Recherches Cliniques de Montréal, Montréal, QC, Canada
| | - Mathieu Ferron
- Unité de recherche en physiologie moléculaire, Institut de Recherches Cliniques de Montréal, Montréal, QC, Canada
- Programme de biologie moléculaire, Université de Montréal, Montréal, QC, Canada
- Département de Médecine, Université de Montréal, Montréal, QC, Canada
- Division of Experimental Medicine, McGill University, Montréal, QC, Canada
- *Correspondence: Mathieu Ferron,
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Research Models for Studying Vascular Calcification. Int J Mol Sci 2020; 21:ijms21062204. [PMID: 32210002 PMCID: PMC7139511 DOI: 10.3390/ijms21062204] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2020] [Revised: 03/17/2020] [Accepted: 03/18/2020] [Indexed: 12/14/2022] Open
Abstract
Calcification of the vessel wall contributes to high cardiovascular morbidity and mortality. Vascular calcification (VC) is a systemic disease with multifaceted contributing and inhibiting factors in an actively regulated process. The exact underlying mechanisms are not fully elucidated and reliable treatment options are lacking. Due to the complex pathophysiology, various research models exist evaluating different aspects of VC. This review aims to give an overview of the cell and animal models used so far to study the molecular processes of VC. Here, in vitro cell culture models of different origins, ex vivo settings using aortic tissue and various in vivo disease-induced animal models are summarized. They reflect different aspects and depict the (patho)physiologic mechanisms within the VC process.
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Abstract
Over the past 25 years, successive cloning of SLC34A1, SLC34A2 and SLC34A3, which encode the sodium-dependent inorganic phosphate (Pi) cotransport proteins 2a-2c, has facilitated the identification of molecular mechanisms that underlie the regulation of renal and intestinal Pi transport. Pi and various hormones, including parathyroid hormone and phosphatonins, such as fibroblast growth factor 23, regulate the activity of these Pi transporters through transcriptional, translational and post-translational mechanisms involving interactions with PDZ domain-containing proteins, lipid microdomains and acute trafficking of the transporters via endocytosis and exocytosis. In humans and rodents, mutations in any of the three transporters lead to dysregulation of epithelial Pi transport with effects on serum Pi levels and can cause cardiovascular and musculoskeletal damage, illustrating the importance of these transporters in the maintenance of local and systemic Pi homeostasis. Functional and structural studies have provided insights into the mechanism by which these proteins transport Pi, whereas in vivo and ex vivo cell culture studies have identified several small molecules that can modify their transport function. These small molecules represent potential new drugs to help maintain Pi homeostasis in patients with chronic kidney disease - a condition that is associated with hyperphosphataemia and severe cardiovascular and skeletal consequences.
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FGF23 at the crossroads of phosphate, iron economy and erythropoiesis. Nat Rev Nephrol 2019; 16:7-19. [PMID: 31519999 DOI: 10.1038/s41581-019-0189-5] [Citation(s) in RCA: 149] [Impact Index Per Article: 29.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/24/2019] [Indexed: 12/20/2022]
Abstract
Fibroblast growth factor 23 (FGF23) was initially characterized as an important regulator of phosphate and calcium homeostasis. New research advances demonstrate that FGF23 is also linked to iron economy, inflammation and erythropoiesis. These advances have been fuelled, in part, by the serendipitous development of two distinct FGF23 assays that can substitute for invasive bone biopsies to infer the activity of the three main steps of FGF23 regulation in bone: transcription, post-translational modification and peptide cleavage. This 'liquid bone biopsy for FGF23 dynamics' enables large-scale longitudinal studies of FGF23 regulation that would otherwise be impossible in humans. The balance between FGF23 production, post-translational modification and cleavage is maintained or perturbed in different hereditary monogenic conditions and in acquired conditions that mimic these genetic disorders, including iron deficiency, inflammation, treatment with ferric carboxymaltose and chronic kidney disease. Looking ahead, a deeper understanding of the relationships between FGF23 regulation, iron homeostasis and erythropoiesis can be leveraged to devise novel therapeutic targets for treatment of anaemia and states of FGF23 excess, including chronic kidney disease.
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Abstract
PURPOSE OF REVIEW The phosphaturic hormone FGF23 is produced primarily in osteoblasts/osteocytes and is known to respond to increases in serum phosphate and 1,25(OH)2 vitamin D (1,25D). Novel regulators of FGF23 were recently identified, and may help explain the pathophysiologies of several diseases. This review will focus on recent studies examining the synthesis and actions of FGF23. RECENT FINDINGS The synthesis of FGF23 in response to 1,25D is similar to other steroid hormone targets, but the cellular responses to phosphate remain largely unknown. The activity of intracellular processing genes control FGF23 glycosylation and phosphorylation, providing critical functions in determining the serum levels of bioactive FGF23. The actions of FGF23 largely occur through its co-receptor αKlotho (KL) under normal circumstances, but FGF23 has KL-independent activity during situations of high concentrations. SUMMARY Recent work regarding FGF23 synthesis and bioactivity, as well as considerations for diseases of altered phosphate balance will be reviewed.
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Affiliation(s)
- Megan L Noonan
- Department of Medical & Molecular Genetics, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Kenneth E White
- Department of Medical & Molecular Genetics, Indiana University School of Medicine, Indianapolis, IN, USA
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Clinkenbeard EL, White KE. Heritable and acquired disorders of phosphate metabolism: Etiologies involving FGF23 and current therapeutics. Bone 2017; 102:31-39. [PMID: 28159712 PMCID: PMC5537045 DOI: 10.1016/j.bone.2017.01.034] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/30/2016] [Revised: 01/20/2017] [Accepted: 01/29/2017] [Indexed: 10/20/2022]
Abstract
Phosphate is critical for many cellular processes and structural functions, including as a key molecule for nucleic acid synthesis and energy metabolism, as well as hydroxyapatite formation in bone. Therefore it is critical to maintain tight regulation of systemic phosphate levels. Based upon its broad biological importance, disruption of normal phosphate homeostasis has detrimental effects on skeletal integrity and overall health. Investigating heritable diseases of altered phosphate metabolism has led to key discoveries underlying the regulation and systemic actions of the phosphaturic hormone Fibroblast growth factor-23 (FGF23). Both molecular and clinical studies have revealed novel targets for the development and optimization of therapies for disorders of phosphate handling. This review will focus upon the bridge between genetic discoveries involving disorders of altered FGF23 bioactivity, as well as describe how these findings have translated into pharmacologic application.
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Affiliation(s)
- Erica L Clinkenbeard
- Department of Medical and Molecular Genetics, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Kenneth E White
- Department of Medical and Molecular Genetics, Indiana University School of Medicine, Indianapolis, IN, USA.
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Song L, Linstedt AD. Inhibitor of ppGalNAc-T3-mediated O-glycosylation blocks cancer cell invasiveness and lowers FGF23 levels. eLife 2017; 6:e24051. [PMID: 28362263 PMCID: PMC5407854 DOI: 10.7554/elife.24051] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2016] [Accepted: 03/30/2017] [Indexed: 01/12/2023] Open
Abstract
Small molecule inhibitors of site-specific O-glycosylation by the polypeptide N-acetylgalactosaminyltransferase (ppGalNAc-T) family are currently unavailable but hold promise as therapeutics, especially if selective against individual ppGalNAc-T isozymes. To identify a compound targeting the ppGalNAc-T3 isozyme, we screened libraries to find compounds that act on a cell-based fluorescence sensor of ppGalNAc-T3 but not on a sensor of ppGalNAc-T2. This identified a hit that subsequent in vitro analysis showed directly binds and inhibits purified ppGalNAc-T3 with no detectable activity against either ppGalNAc-T2 or ppGalNAc-T6. Remarkably, the inhibitor was active in two medically relevant contexts. In cell culture, it opposed increased cancer cell invasiveness driven by upregulated ppGalNAc-T3 suggesting the inhibitor might be anti-metastatic. In cells and mice, it blocked ppGalNAc-T3-mediated glycan-masking of FGF23 thereby increasing its cleavage, a possible treatment of chronic kidney disease. These findings establish a pharmacological approach for the ppGalNAc-transferase family and suggest that targeting specific ppGalNAc-transferases will yield new therapeutics.
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Affiliation(s)
- Lina Song
- Department of Biological Sciences, Carnegie Mellon University, Pittsburgh, United States
| | - Adam D Linstedt
- Department of Biological Sciences, Carnegie Mellon University, Pittsburgh, United States
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Sanchez CP, Mohan S. Genetic Knockout and Rescue Studies in Mice Unravel Abnormal Phosphorus Threshold in Hypophosphatemic Rickets. Endocrinology 2017; 158:455-457. [PMID: 28430915 PMCID: PMC5460786 DOI: 10.1210/en.2017-00030] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/05/2017] [Accepted: 01/11/2017] [Indexed: 11/19/2022]
Affiliation(s)
| | - Subburaman Mohan
- Medicine, and
- Orthopedics, Loma Linda University, Loma Linda, California 92354; and
- Musculoskeletal Disease Center, VA Loma Linda Healthcare System, Loma Linda, California 92357
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Kinoshita S, Kawai M. The FGF23/KLOTHO Regulatory Network and Its Roles in Human Disorders. VITAMINS AND HORMONES 2016; 101:151-74. [PMID: 27125741 DOI: 10.1016/bs.vh.2016.02.001] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The functions of Klotho (KL) are multifaceted and include the regulation of aging and mineral metabolism. It was originally identified as the gene responsible for premature aging-like symptoms in mice and was subsequently shown to function as a coreceptor in the fibroblast growth factor (FGF) 23 signaling pathway. The discovery of KL as a partner for FGF23 led to significant advances in understanding of the molecular mechanisms underlying phosphate and vitamin D metabolism, and simultaneously clarified the pathogenic roles of the FGF23 signaling pathway in human diseases. These novel insights led to the development of new strategies to combat disorders associated with the dysregulated metabolism of phosphate and vitamin D, and clinical trials on the blockade of FGF23 signaling in X-linked hypophosphatemic rickets are ongoing. Molecular and functional insights on KL and FGF23 have been discussed in this review and were extended to how dysregulation of the FGF23/KL axis causes human disorders associated with abnormal mineral metabolism.
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Affiliation(s)
- S Kinoshita
- Osaka Medical Center and Research Institute for Maternal and Child Health, Izumi, Japan
| | - M Kawai
- Osaka Medical Center and Research Institute for Maternal and Child Health, Izumi, Japan.
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Abstract
The regulation of phosphate metabolism as an influence on bone homeostasis is profound. Recent advances in understanding the systemic control of Fibroblast growth factor-23 (FGF23) has uncovered novel effectors of endocrine feedback loops for calcium, phosphate, and vitamin D balance that interact with 'traditional' feedback loops for mineral metabolism. Not only are these findings re-shaping research studying phosphate handling and skeletal interactions, they have provided new therapeutic interventions. Emerging data support that the control of FGF23 production in bone and its circulating concentrations is a multi-layered process, with some influences affecting FGF23 transcription and some post-translational modification of the secreted, bioactive protein. Additionally, the actions of FGF23 on its target tissues via its co-receptor αKlotho, are subject to regulatory events just coming to light. The recent findings of systemic influences on circulating FGF23 and the downstream manifestations on bone homeostasis will be reviewed herein.
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Affiliation(s)
- Erica L Clinkenbeard
- Department of Medical and Molecular Genetics, Division of Molecular Genetics and Gene Therapy, Indiana University School of Medicine, Indianapolis, IN 46202
| | - Kenneth E White
- Department of Medical and Molecular Genetics, Division of Molecular Genetics and Gene Therapy, Indiana University School of Medicine, Indianapolis, IN 46202
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