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Grigore TV, Zuidscherwoude M, Olauson H, Hoenderop JG. Lessons from Klotho mouse models to understand mineral homeostasis. Acta Physiol (Oxf) 2024:e14220. [PMID: 39176993 DOI: 10.1111/apha.14220] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2024] [Revised: 07/30/2024] [Accepted: 08/14/2024] [Indexed: 08/24/2024]
Abstract
AIM Klotho, a key component of the endocrine fibroblast growth factor receptor-fibroblast growth factor axis, is a multi-functional protein that impacts renal electrolyte handling. The physiological significance of Klotho will be highlighted in the regulation of calcium, phosphate, and potassium metabolism. METHODS In this review, we compare several murine models with different renal targeted deletions of Klotho and the insights into the molecular and physiological function that these models offer. RESULTS In vivo, Klotho deficiency is associated with severely impaired mineral metabolism, with consequences on growth, longevity and disease development. Additionally, we explore the perspectives of Klotho in renal pathology and vascular events, as well as potential Klotho treatment options. CONCLUSION This comprehensive review emphasizes the use of Klotho to shed light on deciphering the renal molecular in vivo mechanisms in electrolyte handling, as well as novel therapeutic interventions.
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Affiliation(s)
- Teodora V Grigore
- Department of Medical BioSciences, Radboud Research Institute for Medical Innovation, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Malou Zuidscherwoude
- Department of Medical BioSciences, Radboud Research Institute for Medical Innovation, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Hannes Olauson
- Division of Pathology, Department of Laboratory Medicine, Karolinska Institutet, Stockholm, Sweden
| | - Joost G Hoenderop
- Department of Medical BioSciences, Radboud Research Institute for Medical Innovation, Radboud University Medical Center, Nijmegen, The Netherlands
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Liu J, Wang H, Liu Q, Long S, Wu Y, Wang N, Lin W, Chen G, Lin M, Wen J. Klotho exerts protection in chronic kidney disease associated with regulating inflammatory response and lipid metabolism. Cell Biosci 2024; 14:46. [PMID: 38584258 PMCID: PMC11000353 DOI: 10.1186/s13578-024-01226-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2023] [Accepted: 03/27/2024] [Indexed: 04/09/2024] Open
Abstract
BACKGROUND The anti-aging protein Klotho plays a protective role in kidney disease, but its potential as a biomarker for chronic kidney disease (CKD) is controversial. Additionally, the main pathways through which Klotho exerts its effects on CKD remain unclear. Therefore, we used bioinformatics and clinical data analysis to determine its role in CKD. RESULTS We analyzed the transcriptomic and clinical data from the Nephroseq v5 database and found that the Klotho gene was mainly expressed in the tubulointerstitium, and its expression was significantly positively correlated with estimated glomerular filtration rate (eGFR) and negatively correlated with blood urea nitrogen (BUN) in CKD. We further found that Klotho gene expression was mainly negatively associated with inflammatory response and positively associated with lipid metabolism in CKD tubulointerstitium by analyzing two large sample-size CKD tubulointerstitial transcriptome datasets. By analyzing 10-year clinical data from the National Health and Nutrition Examination Survey (NHANES) 2007-2016, we also found that Klotho negatively correlated with inflammatory biomarkers and triglyceride and positively correlated with eGFR in the CKD population. Mediation analysis showed that Klotho could improve renal function in the general population by modulating the inflammatory response and lipid metabolism, while in the CKD population, it primarily manifested by mediating the inflammatory response. Restricted cubic spline (RCS) analysis showed that the optimal concentration range for Klotho to exert its biological function was around 1000 pg/ml. Kaplan-Meier curves showed that lower cumulative hazards of all-cause mortality in participants with higher levels of Klotho. We also demonstrated that Klotho could reduce cellular inflammatory response and improve cellular lipid metabolism by establishing an in vitro model similar to CKD. CONCLUSIONS Our results suggest that Klotho exerts protection in CKD, which may be mainly related to the regulation of inflammatory response and lipid metabolism, and it can serve as a potential biomarker for CKD.
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Affiliation(s)
- Junhui Liu
- Shengli Clinical Medical College of Fujian Medical University, Fujian Medical University, Fuzhou, China
- Department of Endocrinology, Fujian Provincial Hospital, Shengli Clinical Medical College of Fujian Medical University, Fuzhou, China
| | - Huaicheng Wang
- Shengli Clinical Medical College of Fujian Medical University, Fujian Medical University, Fuzhou, China
| | - Qinyu Liu
- Shengli Clinical Medical College of Fujian Medical University, Fujian Medical University, Fuzhou, China
- Department of Endocrinology, Fujian Provincial Hospital, Shengli Clinical Medical College of Fujian Medical University, Fuzhou, China
| | - Shushu Long
- Shengli Clinical Medical College of Fujian Medical University, Fujian Medical University, Fuzhou, China
- Department of Endocrinology, Fujian Provincial Hospital, Shengli Clinical Medical College of Fujian Medical University, Fuzhou, China
| | - Yanfang Wu
- Shengli Clinical Medical College of Fujian Medical University, Fujian Medical University, Fuzhou, China
- Department of Endocrinology, Fujian Provincial Hospital, Shengli Clinical Medical College of Fujian Medical University, Fuzhou, China
| | - Nengying Wang
- Shengli Clinical Medical College of Fujian Medical University, Fujian Medical University, Fuzhou, China
- Department of Endocrinology, Fujian Provincial Hospital, Shengli Clinical Medical College of Fujian Medical University, Fuzhou, China
| | - Wei Lin
- Shengli Clinical Medical College of Fujian Medical University, Fujian Medical University, Fuzhou, China
- Department of Endocrinology, Fujian Provincial Hospital, Shengli Clinical Medical College of Fujian Medical University, Fuzhou, China
| | - Gang Chen
- Shengli Clinical Medical College of Fujian Medical University, Fujian Medical University, Fuzhou, China.
- Department of Endocrinology, Fujian Provincial Hospital, Shengli Clinical Medical College of Fujian Medical University, Fuzhou, China.
| | - Miao Lin
- Shengli Clinical Medical College of Fujian Medical University, Fujian Medical University, Fuzhou, China.
- Department of Nephrology, Provincial Clinical College, Fujian Provincial Hospital, Fujian Medical University, Fuzhou, China.
| | - Junping Wen
- Shengli Clinical Medical College of Fujian Medical University, Fujian Medical University, Fuzhou, China.
- Department of Endocrinology, Fujian Provincial Hospital, Shengli Clinical Medical College of Fujian Medical University, Fuzhou, China.
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Soomro QH, Charytan DM. New Insights on Cardiac Arrhythmias in Patients With Kidney Disease. Semin Nephrol 2024; 44:151518. [PMID: 38772780 DOI: 10.1016/j.semnephrol.2024.151518] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/23/2024]
Abstract
The risk of arrhythmia and its management become increasingly complex as kidney disease progresses. This presents a multifaceted clinical challenge. Our discussion addresses these specific challenges relevant to patients as their kidney disease advances. We highlight numerous opportunities for enhancing the current standard of care within this realm. Additionally, this review delves into research concerning early detection, prevention, diagnosis, and treatment of various arrhythmias spanning the spectrum of kidney disease.
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Kassianides X, Bhandari S. The differential effect of modern intravenous iron on fibroblast growth factor 23 and phosphate in non-dialysis dependent CKD - the exploratory randomized controlled double-blind ExplorIRON-CKD study. BMC Nephrol 2024; 25:54. [PMID: 38347520 PMCID: PMC10860218 DOI: 10.1186/s12882-023-03440-7] [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: 07/21/2023] [Accepted: 12/14/2023] [Indexed: 02/15/2024] Open
Abstract
BACKGROUND Intravenous iron is commonly used in patients with non-dialysis-dependent chronic kidney disease (CKD). Modern intravenous iron compounds (e.g. ferric derisomaltose (FDI), ferric carboxymaltose (FCM)) are increasingly utilized with similar efficacy. A differential effect in terms of hypophosphatemia has been noted following administration of FCM, which may be related to fibroblast growth factor 23 (FGF23). This study was designed to examine the comparative effects of FDI and FCM on FGF23, phosphate and other markers of bone turnover. METHODS The single-center double-blind randomized controlled trial "Iron and Phosphaturia - ExplorIRON-CKD" primarily assessed the effects of FCM and FDI on intact FGF23 and phosphate, whilst also studying the impact on vitamin D, parathyroid hormone and phosphaturia. Bone markers including alkaline phosphatase, bone-specific alkaline phosphatase, procollagen type 1 N-terminal propeptide and carboxy-terminal collagen cross-linked telopeptide were monitored. Non-dialysis-dependent CKD patients (stage 3a-5) with iron deficiency with/without anemia (serum ferritin < 200 µg/L or transferrin saturation = 20% and serum ferritin 200-299 µg/L) were randomized to receive FDI or FCM in a 1:1 ratio. At baseline 1000 mg of intravenous iron was administered followed by 500-1000 mg at 1 month to achieve replenishment. Measurements were performed at baseline, 1-2 days following iron administration, 2 weeks, 1 month (second iron administration), 1-2 days following second administration, 2 months and 3 months following initial infusion. RESULTS Twenty-six patients participated in the trial; 14 randomized to FDI and 12 to FCM. Intact FGF23 increased following administration of iron, and the increase was significantly higher with FCM compared to FDI (Baseline to 1-2 days following 1st administration: FDI: 3.0 (IQR: - 15.1 - 13.8) % vs. FCM: 146.1 (IQR: 108.1-203.1) %; p < 0.001 and Baseline to 1-2 days following 2nd administration: FDI: 3.2 (IQR: - 3.5 - 25.4) % vs. FCM: 235.1 (138.5-434.6) %; p = 0.001). Phosphate levels decreased in the FCM group, causing a significant difference versus FDI 2 weeks following administration of the first dose. A significantly greater decrease in 1,25 (OH)2 Vitamin D was noted with FCM. Several markers of bone turnover significantly changed following administration of FCM but not FDI. CONCLUSIONS The study suggests a differential effect on FGF23 following administration of FCM compared to FDI in non-dialysis-dependent CKD patients, similar to other patient groups. This may lead to changes consistent with hypovitaminosis D and alterations in bone turnover with potential clinical consequences. Further definitive studies are required to understand these differences of intravenous iron compounds. TRIAL REGISTRATION European Union Drug Regulating Authorities Clinical Trials Database (EudraCT) number: 2019-004370-26 ( https://www.clinicaltrialsregister.eu/ctr-search/trial/2019-004370-26/GB ) (First date of trial registration: 03/12/2019).
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Affiliation(s)
- Xenophon Kassianides
- Academic Renal Research Department, Hull University Teaching Hospitals NHS Trust and the Hull York Medical School, Kingston upon Hull, UK.
| | - Sunil Bhandari
- Academic Renal Research Department, Hull University Teaching Hospitals NHS Trust and the Hull York Medical School, Kingston upon Hull, UK
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5
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Xiang Z, Wang M, Miao C, Jin D, Wang H. Mechanism of calcitriol regulating parathyroid cells in secondary hyperparathyroidism. Front Pharmacol 2022; 13:1020858. [PMID: 36267284 PMCID: PMC9577402 DOI: 10.3389/fphar.2022.1020858] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2022] [Accepted: 09/15/2022] [Indexed: 12/03/2022] Open
Abstract
A common consequence of chronic renal disease is secondary hyperparathyroidism (SHPT) and is closely related to the mortality and morbidity of uremia patients. Secondary hyperparathyroidism (SHPT) is caused by excessive PTH production and release, as well as parathyroid enlargement. At present, the mechanism of cell proliferation in secondary hyperparathyroidism (SHPT) is not completely clear. Decreased expression of the vitamin D receptor (VDR) and calcium-sensing receptor (CaSR), and 1,25(OH)2D3 insufficiency all lead to a decrease in cell proliferation suppression, and activation of multiple pathways is also involved in cell proliferation in renal hyperparathyroidism. The interaction between the parathormone (PTH) and parathyroid hyperplasia and 1,25(OH)2D3 has received considerable attention. 1,25(OH)2D3 is commonly applied in the therapy of renal hyperparathyroidism. It regulates the production of parathormone (PTH) and parathyroid cell proliferation through transcription and post-transcription mechanisms. This article reviews the role of 1,25(OH)2D3 in parathyroid cells in secondary hyperparathyroidism and its current understanding and potential molecular mechanism.
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Franco ML, Beyerstedt S, Rangel ÉB. Klotho and Mesenchymal Stem Cells: A Review on Cell and Gene Therapy for Chronic Kidney Disease and Acute Kidney Disease. Pharmaceutics 2021; 14:pharmaceutics14010011. [PMID: 35056905 PMCID: PMC8778857 DOI: 10.3390/pharmaceutics14010011] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2021] [Revised: 12/16/2021] [Accepted: 12/17/2021] [Indexed: 02/07/2023] Open
Abstract
Chronic kidney disease (CKD) and acute kidney injury (AKI) are public health problems, and their prevalence rates have increased with the aging of the population. They are associated with the presence of comorbidities, in particular diabetes mellitus and hypertension, resulting in a high financial burden for the health system. Studies have indicated Klotho as a promising therapeutic approach for these conditions. Klotho reduces inflammation, oxidative stress and fibrosis and counter-regulates the renin-angiotensin-aldosterone system. In CKD and AKI, Klotho expression is downregulated from early stages and correlates with disease progression. Therefore, the restoration of its levels, through exogenous or endogenous pathways, has renoprotective effects. An important strategy for administering Klotho is through mesenchymal stem cells (MSCs). In summary, this review comprises in vitro and in vivo studies on the therapeutic potential of Klotho for the treatment of CKD and AKI through the administration of MSCs.
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Affiliation(s)
- Marcella Liciani Franco
- Albert Einstein Research and Education Institute, Hospital Israelita Albert Einstein, Sao Paulo 05652-900, Brazil; (M.L.F.); (S.B.)
| | - Stephany Beyerstedt
- Albert Einstein Research and Education Institute, Hospital Israelita Albert Einstein, Sao Paulo 05652-900, Brazil; (M.L.F.); (S.B.)
| | - Érika Bevilaqua Rangel
- Albert Einstein Research and Education Institute, Hospital Israelita Albert Einstein, Sao Paulo 05652-900, Brazil; (M.L.F.); (S.B.)
- Nephrology Division, Federal University of São Paulo, Sao Paulo 04038-901, Brazil
- Correspondence: ; Tel.: +55-11-2151-2148
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Sprague SM, Martin KJ, Coyne DW. Phosphate Balance and CKD-Mineral Bone Disease. Kidney Int Rep 2021; 6:2049-2058. [PMID: 34386654 PMCID: PMC8343779 DOI: 10.1016/j.ekir.2021.05.012] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2021] [Accepted: 05/10/2021] [Indexed: 12/29/2022] Open
Abstract
Chronic kidney disease-mineral bone disorder (CKD-MBD) is a common comorbidity in patients with CKD. Characterized by laboratory abnormalities, bone abnormality, and vascular calcification, CKD-MBD encompasses a group of mineral and hormone disturbances that are strongly associated with increased cardiovascular (CV) morbidity and mortality. Abnormal serum phosphate concentrations are an independent risk factor for CV morbidity and mortality, and overall mortality. Phosphate retention plays a central role in initiating and driving many other disturbances in CKD-MBD (e.g., increased parathyroid hormone and fibroblast growth factor 23 concentrations, hypocalcemia, low vitamin D) that are also linked to increased CV risk. Thus, effective phosphate control is a logical therapeutic target for CKD-MBD treatment. Current phosphate management strategies (dietary restrictions, dialysis, phosphate binders) are insufficient to consistently achieve and maintain target phosphate concentrations in patients on dialysis. Phosphate binders reduce available phosphate for intestinal absorption but do not impair the dominant phosphate absorption pathway. Novel therapies that consider new mechanistic understandings of intestinal phosphate absorption are needed. One such therapy is tenapanor, a targeted sodium-hydrogen exchanger isoform 3 inhibitor that has been shown to reduce serum phosphate concentrations in multiple clinical trials. Tenapanor has a novel mechanism of action that reduces intestinal phosphate absorption in the primary paracellular phosphate absorption pathway.
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Affiliation(s)
- Stuart M. Sprague
- Division of Nephrology and Hypertension, NorthShore University Health System, Evanston, IL, USA
| | | | - Daniel W. Coyne
- Department of Medicine, Washington University School of Medicine, St. Louis, MO, USA
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8
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Tang PK, Geddes RF, Jepson RE, Elliott J. A feline-focused review of chronic kidney disease-mineral and bone disorders - Part 1: Physiology of calcium handling. Vet J 2021; 275:105719. [PMID: 34311095 DOI: 10.1016/j.tvjl.2021.105719] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2020] [Revised: 06/03/2021] [Accepted: 07/21/2021] [Indexed: 01/01/2023]
Abstract
Mineral derangements are a common consequence of chronic kidney disease (CKD). Despite the well-established role of phosphorus in the pathophysiology of CKD, the implications of calcium disturbances associated with CKD remain equivocal. Calcium plays an essential role in numerous physiological functions in the body and is a fundamental structural component of bone. An understanding of calcium metabolism is required to understand the potential adverse clinical implications and outcomes secondary to the (mal)adaptation of calcium-regulating hormones in CKD. The first part of this two-part review covers the physiology of calcium homeostasis (kidneys, intestines and bones) and details the intimate relationships between calcium-regulating hormones (parathyroid hormone, calcitriol, fibroblast growth factor 23, α-Klotho and calcitonin) and the role of the calcium-sensing receptor.
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Affiliation(s)
- Pak-Kan Tang
- Department of Comparative Biomedical Sciences, Royal Veterinary College, University of London, London, UK.
| | - Rebecca F Geddes
- Department of Clinical Science and Services, Royal Veterinary College, University of London, London, UK
| | - Rosanne E Jepson
- Department of Clinical Science and Services, Royal Veterinary College, University of London, London, UK
| | - Jonathan Elliott
- Department of Comparative Biomedical Sciences, Royal Veterinary College, University of London, London, UK
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Habas E, Eledrisi M, Khan F, Elzouki ANY. Secondary Hyperparathyroidism in Chronic Kidney Disease: Pathophysiology and Management. Cureus 2021; 13:e16388. [PMID: 34408941 PMCID: PMC8362860 DOI: 10.7759/cureus.16388] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/14/2021] [Indexed: 12/25/2022] Open
Abstract
Serum calcium concentration is the main determinant of parathyroid hormone (PTH) release. Defect in the activation of vitamin D in the kidneys due to chronic kidney disease (CKD) leads to hypocalcemia and hyperphosphatemia, resulting in a compensatory increase in parathyroid gland cellularity and parathyroid hormone production and causing secondary hyperparathyroidism (SHP). Correction and maintenance of normal serum calcium and phosphate are essential to preventing SHP, hungry bone disease, cardiovascular events, and anemia development. Understanding the pathophysiology of PTH and possible therapeutic agents can reduce the development and associated complications of SHP in patients with CKD. Medical interventions to control serum calcium, phosphate, and PTH such as vitamin D analogs, calcium receptor blockers, and parathyroidectomy are needed in some CKD patients. In this review, we discuss the pathophysiology, clinical presentation, and management of SHP in CKD patients.
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Affiliation(s)
| | | | - Fahmi Khan
- Internal Medicine, Hamad General Hospital, Doha, QAT
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10
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He K, Han S, An L, Zhang J. Inhibition of MicroRNA-214 Alleviates Lung Injury and Inflammation via Increasing FGFR1 Expression in Ventilator-Induced Lung Injury. Lung 2021; 199:63-72. [PMID: 33389067 DOI: 10.1007/s00408-020-00415-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2020] [Accepted: 12/11/2020] [Indexed: 11/27/2022]
Abstract
PURPOSE Ventilator-induced lung injury (VILI) is an additional inflammatory injury caused by mechanical ventilation (MV). This study aimed to determine the effects of microRNA-214 (miR-214) on VILI and its underlying mechanism of action. METHODS To develop a VILI mouse model, mice were subjected to MV. The expression of miR-214 was detected by qRT-PCR. The macrophages, fibroblasts, epithelial cells, and endothelial cells were isolated from lung tissues by fluorescence-activated cell sorting. The histopathological changes of lung, lung wet/dry weight (W/D) ratio, and myeloperoxidase (MPO) activity were used to evaluate the degree of lung injury. The levels of pro-inflammatory cytokines in bronchoalveolar lavage fluid (BALF) were measured by enzyme-linked immunosorbent assay (ELISA). Dual-luciferase reporter assay was performed to determine the interactions between miR-214 and FGFR1. Western blot was used to detect the protein expression of FGFR1, p-AKT, and p-PI3K. RESULTS The expression of miR-214 was increased in lung tissues and macrophages, fibroblasts, epithelial cells, and endothelial cells isolated from lung tissues in VILI mice. MiR-214 inhibition decreased the histopathological changes of lung, lung W/D ratio, MPO activity, and pro-inflammatory cytokines levels in BALF in VILI mice. FGFR1 was targeted by miR-214. The protein expression of FGFR1 was decreased in VILI mice. Ponatinib (FGFR1 inhibitor) reversed the suppressive effects of miR-214 inhibition on lung injury and inflammation of VILI mice. MiR-214 increased the activity of PI3K/AKT pathway by regulating FGFR1. CONCLUSIONS Inhibition of miR-214 attenuated lung injury and inflammation in VILI mice by increasing FGFR1 expression, providing a novel therapeutic target for VILI.
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Affiliation(s)
- Kun He
- Department of Anesthesiology, The Fourth Hospital of Shijiazhuang, No. 206, Zhongshan East Road, Shijiazhuang, 050011, Hebei, China
| | - Shuang Han
- Department of Anesthesiology, Hebei General Hospital, No. 348, Heping West Road, Shijiazhuang, 050051, Hebei, China
| | - Li An
- Department of Anesthesiology, The Fourth Hospital of Shijiazhuang, No. 206, Zhongshan East Road, Shijiazhuang, 050011, Hebei, China.
| | - Jin Zhang
- Department of Anesthesiology, The Fourth Hospital of Shijiazhuang, No. 206, Zhongshan East Road, Shijiazhuang, 050011, Hebei, China
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Maxwell KD, Chuang J, Chaudhry M, Nie Y, Bai F, Sodhi K, Liu J, Shapiro JI. The potential role of Na-K-ATPase and its signaling in the development of anemia in chronic kidney disease. Am J Physiol Renal Physiol 2020; 320:F234-F242. [PMID: 33356956 DOI: 10.1152/ajprenal.00244.2020] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Chronic kidney disease (CKD) is one of the most prominent diseases affecting our population today. According to the Factsheet published by Centers for Disease Control and Prevention (CDC), it effects approximately 15% of the total population in the United States in some way, shape, or form. Within the myriad of symptomatology associated with CKD, one of the most prevalent factors in terms of affecting quality of life is anemia. Anemia of CKD cannot be completely attributed to one mechanism or cause, but rather has a multifactorial origin in the pathophysiology of CKD. While briefly summarizing well-documented risk factors, this review, as a hypothesis, aims to explore the possible role of Na-K-ATPase and its signaling function [especially recent identified reactive oxygen species (ROS) amplification function] in the interwoven mechanisms of development of the anemia of CKD.
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Affiliation(s)
- Kyle D Maxwell
- Department of Biomsedical Sciences, Joan C. Edwards School of Medicine, Marshall University, Huntington, West Virginia
| | - Justin Chuang
- Department of Biomsedical Sciences, Joan C. Edwards School of Medicine, Marshall University, Huntington, West Virginia
| | - Muhammad Chaudhry
- Department of Biomsedical Sciences, Joan C. Edwards School of Medicine, Marshall University, Huntington, West Virginia
| | - Ying Nie
- Department of Biomsedical Sciences, Joan C. Edwards School of Medicine, Marshall University, Huntington, West Virginia
| | - Fang Bai
- Department of Biomsedical Sciences, Joan C. Edwards School of Medicine, Marshall University, Huntington, West Virginia
| | - Komal Sodhi
- Department of Biomsedical Sciences, Joan C. Edwards School of Medicine, Marshall University, Huntington, West Virginia.,Department of Medicine, Joan C. Edwards School of Medicine, Marshall University, Huntington, West Virginia
| | - Jiang Liu
- Department of Biomsedical Sciences, Joan C. Edwards School of Medicine, Marshall University, Huntington, West Virginia
| | - Joseph I Shapiro
- Department of Medicine, Joan C. Edwards School of Medicine, Marshall University, Huntington, West Virginia
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12
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Laflamme D, Backus R, Brown S, Butterwick R, Czarnecki-Maulden G, Elliott J, Fascetti A, Polzin D. A review of phosphorus homeostasis and the impact of different types and amounts of dietary phosphate on metabolism and renal health in cats. J Vet Intern Med 2020; 34:2187-2196. [PMID: 33159358 PMCID: PMC7694857 DOI: 10.1111/jvim.15961] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2020] [Revised: 10/11/2020] [Accepted: 10/27/2020] [Indexed: 12/14/2022] Open
Abstract
Elevated concentrations of serum phosphate are linked with progression and increased case fatality rate in animals and humans with chronic kidney disease. Elevated concentrations of serum phosphate can be a risk factor for development of renal and cardiovascular diseases or osteoporosis in previously healthy people. In rodents, an excess intake of dietary phosphorus combined with an inverse dietary calcium : phosphorus ratio (<1 : 1) contributes to renal calcification. Renal injury also has occured in cats fed experimental diets supplemented with highly soluble phosphate salts, especially in diets with inverse calcium : phosphorus ratios. However, not all phosphorus sources contribute similarly to this effect. This review, which focuses on cats, summarizes the published evidence regarding phosphorus metabolism and homeostasis, including the relative impact of different dietary phosphorus sources, and their impact on the kidneys. No data currently shows that commercial cat foods induce renal injury. However, some diets contain high amounts of phosphorus relative to recommendations and some have inverse Ca : P ratios and so could increase the risk for development of kidney disease. While limiting the use of highly soluble phosphates appears to be important, there are insufficient data to support a specific upper limit for phosphate intake. This review also proposes areas where additional research is needed in order to strengthen conclusions and recommendations regarding dietary phosphorus for cats.
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Affiliation(s)
| | - Robert Backus
- Department of Veterinary Medicine and Surgery, College of Veterinary Medicine, University of Missouri, Columbia, Missouri, USA
| | - Scott Brown
- College of Veterinary Medicine, University of Georgia, Athens, Georgia, USA
| | | | | | - Jonathan Elliott
- Royal Veterinary College, University of London, London, United Kingdom
| | - Andrea Fascetti
- Department of Molecular Biosciences, University of California, Davis, California, USA
| | - David Polzin
- Veterinary Clinical Sciences Department, College of Veterinary Medicine, University of Minnesota, St Paul, Minnesota, USA
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Abstract
Parathyroid hormone is an essential regulator of extracellular calcium and phosphate. PTH enhances calcium reabsorption while inhibiting phosphate reabsorption in the kidneys, increases the synthesis of 1,25-dihydroxyvitamin D, which then increases gastrointestinal absorption of calcium, and increases bone resorption to increase calcium and phosphate. Parathyroid disease can be an isolated endocrine disorder or part of a complex syndrome. Genetic mutations can account for diseases of parathyroid gland formulation, dysregulation of parathyroid hormone synthesis or secretion, and destruction of the parathyroid glands. Over the years, a number of different options are available for the treatment of different types of parathyroid disease. Therapeutic options include surgical removal of hypersecreting parathyroid tissue, administration of parathyroid hormone, vitamin D, activated vitamin D, calcium, phosphate binders, calcium-sensing receptor, and vitamin D receptor activators to name a few. The accurate assessment of parathyroid hormone also provides essential biochemical information to properly diagnose parathyroid disease. Currently available immunoassays may overestimate or underestimate bioactive parathyroid hormone because of interferences from truncated parathyroid hormone fragments, phosphorylation of parathyroid hormone, and oxidation of amino acids of parathyroid hormone.
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Affiliation(s)
- Edward Ki Yun Leung
- Department of Pathology and Laboratory Medicine, Children's Hospital Los Angeles, Los Angeles, CA, United States; Department of Pathology, Keck School of Medicine of University of Southern California, Los Angeles, CA, United States.
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Thongprayoon C, Neyra JA, Hansrivijit P, Medaura J, Leeaphorn N, Davis PW, Kaewput W, Bathini T, Salim SA, Chewcharat A, Aeddula NR, Vallabhajosyula S, Mao MA, Cheungpasitporn W. Serum Klotho in Living Kidney Donors and Kidney Transplant Recipients: A Meta-Analysis. J Clin Med 2020; 9:jcm9061834. [PMID: 32545510 PMCID: PMC7355868 DOI: 10.3390/jcm9061834] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2020] [Revised: 06/07/2020] [Accepted: 06/09/2020] [Indexed: 02/06/2023] Open
Abstract
α-Klotho is a known anti-aging protein that exerts diverse physiological effects, including phosphate homeostasis. Klotho expression occurs predominantly in the kidney and is significantly decreased in patients with chronic kidney disease. However, changes in serum klotho levels and impacts of klotho on outcomes among kidney transplant (KTx) recipients and kidney donors remain unclear. A literature search was conducted using MEDLINE, EMBASE, and Cochrane Database from inception through October 2019 to identify studies evaluating serum klotho levels and impacts of klotho on outcomes among KTx recipients and kidney donors. Study results were pooled and analyzed utilizing a random-effects model. Ten cohort studies with a total of 431 KTx recipients and 5 cohort studies with a total of 108 living kidney donors and were identified. After KTx, recipients had a significant increase in serum klotho levels (at 4 to 13 months post-KTx) with a mean difference (MD) of 243.11 pg/mL (three studies; 95% CI 67.41 to 418.81 pg/mL). Although KTx recipients had a lower serum klotho level with a MD of = -234.50 pg/mL (five studies; 95% CI -444.84 to -24.16 pg/mL) compared to healthy unmatched volunteers, one study demonstrated comparable klotho levels between KTx recipients and eGFR-matched controls. Among kidney donors, there was a significant decrease in serum klotho levels post-nephrectomy (day 3 to day 5) with a mean difference (MD) of -232.24 pg/mL (three studies; 95% CI -299.41 to -165.07 pg/mL). At one year following kidney donation, serum klotho levels remained lower than baseline before nephrectomy with a MD of = -110.80 pg/mL (two studies; 95% CI 166.35 to 55.24 pg/mL). Compared to healthy volunteers, living kidney donors had lower serum klotho levels with a MD of = -92.41 pg/mL (two studies; 95% CI -180.53 to -4.29 pg/mL). There is a significant reduction in serum klotho levels after living kidney donation and an increase in serum klotho levels after KTx. Future prospective studies are needed to assess the impact of changes in klotho on clinical outcomes in KTx recipients and living kidney donors.
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Affiliation(s)
- Charat Thongprayoon
- Division of Nephrology and Hypertension, Mayo Clinic, Rochester, MN 55905, USA;
- Correspondence: (C.T.); (W.C.)
| | - Javier A. Neyra
- Division of Nephrology, Bone and Mineral Metabolism, Department of Internal Medicine, University of Kentucky, Lexington, KY 40506, USA;
- Charles and Jane Pak Center for Mineral Metabolism and Clinical Research, Dallas, TX 75390, USA
- Division of Nephrology, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Panupong Hansrivijit
- Department of Internal Medicine, University of Pittsburgh Medical Center Pinnacle, Harrisburg, PA 17105, USA;
| | - Juan Medaura
- Division of Nephrology, Department of Medicine, University of Mississippi Medical Center, Jackson, MS 39216, USA; (J.M.); (P.W.D.); (S.A.S.)
| | - Napat Leeaphorn
- Renal Transplant Program, University of Missouri-Kansas City School of Medicine/Saint Luke’s Health System, Kansas City, MO 64110, USA;
| | - Paul W. Davis
- Division of Nephrology, Department of Medicine, University of Mississippi Medical Center, Jackson, MS 39216, USA; (J.M.); (P.W.D.); (S.A.S.)
| | - Wisit Kaewput
- Department of Military and Community Medicine, Phramongkutklao College of Medicine, Bangkok 10400, Thailand;
| | - Tarun Bathini
- Department of Internal Medicine, University of Arizona, Tucson, AZ 85721, USA;
| | - Sohail Abdul Salim
- Division of Nephrology, Department of Medicine, University of Mississippi Medical Center, Jackson, MS 39216, USA; (J.M.); (P.W.D.); (S.A.S.)
| | - Api Chewcharat
- Division of Nephrology and Hypertension, Mayo Clinic, Rochester, MN 55905, USA;
| | - Narothama Reddy Aeddula
- Division of Nephrology, Department of Medicine, Deaconess Health System, Evansville, IN 47710, USA;
| | | | - Michael A. Mao
- Division of Nephrology and Hypertension, Mayo Clinic, Jacksonville, FL 32224, USA;
| | - Wisit Cheungpasitporn
- Division of Nephrology, Department of Medicine, University of Mississippi Medical Center, Jackson, MS 39216, USA; (J.M.); (P.W.D.); (S.A.S.)
- Correspondence: (C.T.); (W.C.)
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15
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Meng F, Bertucci C, Gao Y, Li J, Luu S, LeBoff MS, Glowacki J, Zhou S. Fibroblast growth factor 23 counters vitamin D metabolism and action in human mesenchymal stem cells. J Steroid Biochem Mol Biol 2020; 199:105587. [PMID: 32004706 DOI: 10.1016/j.jsbmb.2020.105587] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/01/2019] [Revised: 11/15/2019] [Accepted: 01/08/2020] [Indexed: 02/07/2023]
Abstract
Chronic kidney disease (CKD) is associated with elevated circulating fibroblast growth factor 23 (FGF23), impaired renal biosynthesis of 1α,25-dihydroxyvitamin D (1α,25(OH)2D), low bone mass, and increased fracture risk. Our previous data with human mesenchymal stem cells (hMSCs) indicated that vitamin D metabolism in hMSCs is regulated as it is in the kidney and promotes osteoblastogenesis in an autocrine/paracrine manner. In this study, we tested the hypothesis that FGF23 inhibits vitamin D metabolism and action in hMSCs. hMSCs were isolated from discarded marrow during hip arthroplasty, including two subjects receiving hemodialysis and a series of 20 subjects (aged 49-83 years) with estimated glomerular filtration rate (eGFR) data. The direct in vitro effects of rhFGF23 on hMSCs were analyzed by RT-PCR, Western immunoblot, and biochemical assays. Ex vivo analyses showed positive correlations for both secreted and membrane-bound αKlotho gene expression in hMSCs with eGFR of the subjects from whom hMSCs were isolated. There was downregulated constitutive expression of αKlotho, but not FGFR1 in hMSCs obtained from two hemodialysis subjects. In vitro, rhFGF23 countered vitamin D-stimulated osteoblast differentiation of hMSCs by reducing the vitamin D receptor, CYP27B1/1α-hydroxylase, biosynthesis of 1α,25(OH)2D3, and signaling through BMP-7. These data demonstrate that dysregulated vitamin D metabolism in hMSCs may contribute to impaired osteoblastogenesis and altered bone and mineral metabolism in CKD subjects due to elevated FGF23. This supports the importance of intracellular vitamin D metabolism in autocrine/paracrine regulation of osteoblast differentiation in hMSCs.
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Affiliation(s)
- Fangang Meng
- Department of Orthopedic Surgery, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, USA; Department of Joint Surgery, The First Affiliated Hospital of Sun Yat-Sen University, Guangzhou, Guangdong, China
| | - Christopher Bertucci
- Department of Orthopedic Surgery, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, USA
| | - Yuan Gao
- Department of Orthopedic Surgery, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, USA; Department of Orthopedics, Qilu Hospital of Shandong University, Jinan, Shandong, China
| | - Jing Li
- Department of Orthopedic Surgery, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, USA; Department of Endocrinology, West China Hospital, West China School of Medicine, Sichuan University, Chengdu, Sichuan, China
| | - Simon Luu
- Department of Orthopedic Surgery, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, USA
| | - Meryl S LeBoff
- Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, USA
| | - Julie Glowacki
- Department of Orthopedic Surgery, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, USA
| | - Shuanhu Zhou
- Department of Orthopedic Surgery, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, USA.
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16
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Liu Q, Zhu LJ, Waaga-Gasser AM, Ding Y, Cao M, Jadhav SJ, Kirollos S, Shekar PS, Padera RF, Chang YC, Xu X, Zeisberg EM, Charytan DM, Hsiao LL. The axis of local cardiac endogenous Klotho-TGF-β1-Wnt signaling mediates cardiac fibrosis in human. J Mol Cell Cardiol 2019; 136:113-124. [PMID: 31520610 DOI: 10.1016/j.yjmcc.2019.09.004] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/20/2019] [Revised: 08/31/2019] [Accepted: 09/09/2019] [Indexed: 12/16/2022]
Abstract
BACKGROUND Cardiovascular fibrosis is a major contributor to cardiovascular disease, the primary cause of death in patients with chronic kidney disease (CKD). We previously reported expression of endogenous Klotho in human arteries, and that CKD is a state of Klotho deficiency, resulting in vascular calcification, but myocardial expression of Klotho is poorly understood. This study aimed to further clarify endogenous Klotho's functional roles in cardiac fibrosis in patients with underlying CKD. METHODS AND RESULTS Human atrial appendage specimens were collected during cardiac surgery from individuals with or without CKD. Cardiac fibrosis was quantified using trichrome staining. For endogenous Klotho functional studies, primary human cardiomyocytes (HCMs) were treated with uremic serum from CKD patients or recombinant human TGF-β1. The effects of endogenous Klotho in HCMs were studied using Klotho-siRNA and Klotho-plasmid transfection. Both gene and protein expression of endogenous Klotho are found in human heart, but decreased Klotho expression is clearly associated with the degree of cardiac fibrosis in CKD patients. Moreover, we show that endogenous Klotho is expressed by HCMs and cardiac fibroblasts (HCFs) but that HCM expression is suppressed by uremic serum or TGF-β1. Klotho knockdown or overexpression aggravates or mitigates TGF-β1-induced fibrosis and canonical Wnt signaling in HCMs, respectively. Furthermore, co-culture of HCMs with HCFs increases TGF-β1-induced fibrogenic proteins in HCFs, but overexpression of endogenous Klotho in HCMs mitigates this effect, suggesting functional crosstalk between HCMs and HCFs. CONCLUSIONS Our data from analysis of human hearts as well as functional in vitro studies strongly suggests that the loss of cardiac endogenous Klotho in CKD patients, specifically in cardiomyocytes, facilitates intensified TGF-β1 signaling which enables more vigorous cardiac fibrosis through upregulated Wnt signaling. Upregulation of endogenous Klotho inhibits pathogenic Wnt/β-catenin signaling and may offer a novel strategy for prevention and treatment of cardiac fibrosis in CKD patients.
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Affiliation(s)
- Qinghua Liu
- Department of Nephrology, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou 510080, China; Renal Division, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Lang-Jing Zhu
- Department of Nephrology, The Eighth Affiliated Hospital, Sun Yat-sen University, Shenzhen 518033, China; Renal Division, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Ana Maria Waaga-Gasser
- Renal Division, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Yan Ding
- Renal Division, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Minghua Cao
- Renal Division, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Shreyas J Jadhav
- Renal Division, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Sandra Kirollos
- Renal Division, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Prem S Shekar
- Division of Cardiac Surgery, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Robert F Padera
- Department of Pathology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Yu-Chun Chang
- Renal Division, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Xingbo Xu
- Department of Cardiology and Pneumology, University Medical Center of Göttingen, Georg-August University, Göttingen, Lower Saxony 37075, Germany; German Centre for Cardiovascular Research (DZHK), Göttingen, Lower Saxony 37075, Germany
| | - Elisabeth M Zeisberg
- Department of Cardiology and Pneumology, University Medical Center of Göttingen, Georg-August University, Göttingen, Lower Saxony 37075, Germany; German Centre for Cardiovascular Research (DZHK), Göttingen, Lower Saxony 37075, Germany; Nephrology Division, Langone Medical Center, New York University, New York, NY 10016, USA
| | - David M Charytan
- Nephrology Division, Langone Medical Center, New York University, New York, NY 10016, USA.
| | - Li-Li Hsiao
- Renal Division, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA.
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17
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Chandran M, Wong J. Secondary and Tertiary Hyperparathyroidism in Chronic Kidney Disease: An Endocrine and Renal Perspective. Indian J Endocrinol Metab 2019; 23:391-399. [PMID: 31741895 PMCID: PMC6844175 DOI: 10.4103/ijem.ijem_292_19] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Secondary Hyperparathyroidism (SHP) seen as a frequent complication in Chronic Kidney Disease (CKD) has many pathogenetic peculiarities that are still incompletely defined and understood. During the long course of chronic renal failure, SHP can also transform sometimes into the hypercalcemic state characterized by quasi-autonomous production of Parathyroid Hormone from the parathyroid glands: a disorder that is termed Tertiary Hyperparathyroidism. The clinical consequences of SHP in CKD are protean, encompassing bone and mineral abnormalities but as recently identified, also several metabolic and cardiovascular problems, the most important of which is vascular calcification. There have been several advances in the therapeutic armamentarium available for the treatment of SHP, though clear demonstration of a benefit regarding major clinical outcomes with any of the new agents is still lacking. This narrative review summarizes the current understanding about this disorder and highlights some of the recent research on the subject.
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Affiliation(s)
- Manju Chandran
- Department of Endocrinology, Osteoporosis and Bone Metabolism Unit, Singapore General Hospital, Singapore
| | - Jiunn Wong
- Department of Renal Medicine, Singapore General Hospital, Singapore
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18
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Silva AP, Mendes F, Carias E, Gonçalves RB, Fragoso A, Dias C, Tavares N, Café HM, Santos N, Rato F, Leão Neves P, Almeida E. Plasmatic Klotho and FGF23 Levels as Biomarkers of CKD-Associated Cardiac Disease in Type 2 Diabetic Patients. Int J Mol Sci 2019; 20:E1536. [PMID: 30934737 PMCID: PMC6480092 DOI: 10.3390/ijms20071536] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2019] [Revised: 03/20/2019] [Accepted: 03/22/2019] [Indexed: 12/24/2022] Open
Abstract
BACKGROUND Research over the past decade has focused on the role of Klotho as a cardio protective agent that prevents the effects of aging on the heart and reduces the burden of cardiovascular disease CVD. The role of the interaction between fibroblast growth factor 23-(FGF-23)/Klotho in Klotho-mediated actions is still under debate. The main objective was to ascertain the potential use of plasmatic Klotho and FGF23 as markers for CKD-associated cardiac disease and mortality. METHODS This was a prospective analysis conducted in an outpatient diabetic nephropathy clinic, enrolling 107 diabetic patients with stage 2⁻3 CKD. Patients were divided into three groups according to their left ventricular mass index and relative wall thickness. RESULTS Multinomial regression analysis demonstrated that low Klotho and higher FGF-23 levels were linked to a greater risk of concentric hypertrophy. In the generalized linear model (GLM), Klotho, FGF-23 and cardiac geometry groups were statistically significant as independent variables of cardiovascular hospitalization (p = 0.007). According to the Cox regression model, fatal cardiovascular events were associated with the following cardiac geometric classifications; eccentric hypertrophy (p = 0.050); concentric hypertrophy (p = 0.041), and serum phosphate ≥ 3.6 mg/dL (p = 0.025), FGF-23 ≥ 168 (p = 0.0149), α-klotho < 313 (p = 0.044). CONCLUSIONS In our population, Klotho and FGF23 are associated with cardiovascular risk in the early stages of CKD.
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Affiliation(s)
- Ana Paula Silva
- Nephrology Department, Centro Hospitalar Universitário do Algarve, 800-836 Faro, Portugal.
- Departamento de Ciências Biomédicas e Medicina, Universidade do Algarve, 8005-139 Faro, Portugal.
| | - Filipa Mendes
- Nephrology Department, Centro Hospitalar Universitário do Algarve, 800-836 Faro, Portugal.
| | - Eduarda Carias
- Nephrology Department, Centro Hospitalar Universitário do Algarve, 800-836 Faro, Portugal.
| | - Rui Baptista Gonçalves
- Departamento de Ciências Biomédicas e Medicina, Universidade do Algarve, 8005-139 Faro, Portugal.
| | - André Fragoso
- Nephrology Department, Centro Hospitalar Universitário do Algarve, 800-836 Faro, Portugal.
| | - Carolina Dias
- Departamento de Ciências Biomédicas e Medicina, Universidade do Algarve, 8005-139 Faro, Portugal.
| | - Nelson Tavares
- Cardiology Department, Centro Hospitalar Universitário do Algarve, 8000-386 Faro, Portugal.
| | - Hugo Mendonça Café
- Cardiology Department, Centro Hospitalar Universitário do Algarve, 8000-386 Faro, Portugal.
| | - Nélio Santos
- Clinic Pathology Department, Centro Hospitalar Universitário do Algarve, 8000-836, Faro, Portugal.
| | - Fátima Rato
- Clinic Pathology Department, Centro Hospitalar Universitário do Algarve, 8000-836, Faro, Portugal.
| | - Pedro Leão Neves
- Nephrology Department, Centro Hospitalar Universitário do Algarve, 800-836 Faro, Portugal.
- Departamento de Ciências Biomédicas e Medicina, Universidade do Algarve, 8005-139 Faro, Portugal.
| | - Edgar Almeida
- Faculdadade de Medicina da Universidade de Lisboa, 1600-190 Lisboa, Portugal.
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19
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Rodríguez-Ortiz ME, Pendón-Ruiz de Mier MV, Rodríguez M. Parathyroidectomy in dialysis patients: Indications, methods, and consequences. Semin Dial 2019; 32:444-451. [PMID: 30656752 DOI: 10.1111/sdi.12772] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Secondary hyperparathyroidism, characterized by increased PTH synthesis and secretion, is often seen in advanced stages of chronic kidney disease. Excessive proliferation of parathyroid cells leads to the development of diffuse hyperplasia that subsequently progresses to nodular histology. Refractory hyperparathyroidism occurs when parathyroid glands fail to respond to medical therapy. Parathyroidectomy (PTX), surgical resection of parathyroid glands, is usually performed in cases of persistent serum levels of PTH above 1000 pg/mL associated with hypercalcemia or when hyperparathyroidism is refractory to conservative therapy. Parathyroidectomy can be carried out using different procedures: subtotal PTX or total PTX with or without parathyroid autotransplantation. Parathyroid surgery may have undesirable consequences due to PTH oversuppression, such as the development of adynamic bone disease; hungry bone syndrome is quite common after this surgery. However, PTX improves survival and parameters of mineral metabolism. Parathyroidectomy needs to be considered in those patients with severe hyperparathyroidism with a poor response to pharmacological treatment and with distinct undesirable effects of PTH on bone and mineral metabolism parameters.
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Affiliation(s)
- María E Rodríguez-Ortiz
- Maimónides Institute for Biomedical Research (IMIBIC), Córdoba, Spain.,Reina Sofía University Hospital, Córdoba, Spain.,University of Córdoba, Córdoba, Spain.,Spanish Renal Research Network (REDinREN), Institute of Health Carlos III, Madrid, Spain
| | - María V Pendón-Ruiz de Mier
- Maimónides Institute for Biomedical Research (IMIBIC), Córdoba, Spain.,Reina Sofía University Hospital, Córdoba, Spain.,University of Córdoba, Córdoba, Spain.,Spanish Renal Research Network (REDinREN), Institute of Health Carlos III, Madrid, Spain
| | - Mariano Rodríguez
- Maimónides Institute for Biomedical Research (IMIBIC), Córdoba, Spain.,University of Córdoba, Córdoba, Spain.,Spanish Renal Research Network (REDinREN), Institute of Health Carlos III, Madrid, Spain.,Nephrology Service, University Hospital Reina Sofía, Córdoba, Spain
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20
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Zheng CM, Wu CC, Lu CL, Hou YC, Wu MS, Hsu YH, Chen R, Chang TJ, Shyu JF, Lin YF, Lu KC. Hypoalbuminemia differently affects the serum bone turnover markers in hemodialysis patients. Int J Med Sci 2019; 16:1583-1592. [PMID: 31839746 PMCID: PMC6909808 DOI: 10.7150/ijms.39158] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/08/2019] [Accepted: 10/03/2019] [Indexed: 12/20/2022] Open
Abstract
Renal osteodystrophy (ROD) represents bone disorders related to chronic kidney disease (CKD) and several bone biomarkers are used clinically to predict ROD in CKD and hemodialysis (HD) patients. Serum albumin associates with inflammation other than nutritional status in these patients. Chronic inflammation is proved to relate with bone loss, however, the influence of hypoalbuminemia on bone biomarkers is still unclear. In this study, we evaluated the pattern of bone biomarker changes and further studied the influence of hypoalbuminemia on these biomarkers. A total of 300 maintenance HD patients were evaluated and 223 HD patients were included in the study. The patients were grouped according to serum parathyroid hormone (PTH) levels (PTH ≤150 pg/mL, PTH 150-300 pg/mL, PTH 300-600 pg/mL and PTH >600 pg/mL). Bone biomarkers and inflammatory markers were measured and their relation with PTH levels was determined. Significantly increased interleukin-6 (IL-6) and lower albumin levels were noted among PTH>600 pg/mL group. Bone turnover markers were significantly higher in PTH >600 pg/mL group (p< 0.05). Hypoalbuminemia significantly increased the fibroblast growth factor-23 (FGF-23) and procollagen type 1N-terminal propeptide (P1NP) in PTH ≤150 pg/mL, PTH 150-300 pg/mL, PTH 300-600 pg/mL groups, whereas no such relation was noted among PTH> 600 ng/dL group. In conclusion, hypoalbuminemia represents a chronic inflammation which differently relates to bone turnover markers according to serum PTH levels in SHPT patients. Thus, serum albumin measurement should be considered in determining bone disorders among these patients.
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Affiliation(s)
- Cai Mei Zheng
- Graduate Institute of Clinical Medicine, College of Medicine, Taipei Medical University, Taipei 11031, Taiwan.,Division of Nephrology, Department of Internal Medicine, Shuang Ho Hospital, Taipei Medical University, New Taipei City 235, Taiwan
| | - Chia Chao Wu
- Division of Nephrology, Department of Medicine, Tri-Service General Hospital, National Defense Medical Center, Taipei 114, Taiwan
| | - Chien Lin Lu
- Graduate Institute of Clinical Medicine, College of Medicine, Taipei Medical University, Taipei 11031, Taiwan.,Division of Nephrology, Department of Medicine, Fu Jen Catholic University Hospital, School of Medicine, Fu Jen Catholic University, New Taipei City 242, Taiwan
| | - Yi Chou Hou
- Graduate Institute of Clinical Medicine, College of Medicine, Taipei Medical University, Taipei 11031, Taiwan.,Division of Nephrology, Department of Medicine, Cardinal-Tien Hospital, School of Medicine, Fu Jen Catholic University, New Taipei City 23155, Taiwan
| | - Mai Szu Wu
- Graduate Institute of Clinical Medicine, College of Medicine, Taipei Medical University, Taipei 11031, Taiwan.,Division of Nephrology, Department of Internal Medicine, Shuang Ho Hospital, Taipei Medical University, New Taipei City 235, Taiwan
| | - Yung Ho Hsu
- Graduate Institute of Clinical Medicine, College of Medicine, Taipei Medical University, Taipei 11031, Taiwan.,Division of Nephrology, Department of Internal Medicine, Shuang Ho Hospital, Taipei Medical University, New Taipei City 235, Taiwan
| | - Remy Chen
- Chief, Kidney Dialysis Center, Hasuda Hospital, Negane, Hasuda City, Saitama, 3490131, Japan
| | - Tian Jong Chang
- Graduate Institute of Life Sciences, National Defense Medical Center, Taipei 114, Taiwan.,Performance Appraisal Section, Secretary Office, Shuang Ho Hospital, Taipei Medical University, Taipei, Taiwan
| | - Jia Fwu Shyu
- Graduate Institute of Clinical Medicine, College of Medicine, Taipei Medical University, Taipei 11031, Taiwan.,Department of Biology and Anatomy, National Defense Medical Center, Taipei 114, Taiwan
| | - Yuh Feng Lin
- Graduate Institute of Clinical Medicine, College of Medicine, Taipei Medical University, Taipei 11031, Taiwan.,Division of Nephrology, Department of Internal Medicine, Shuang Ho Hospital, Taipei Medical University, New Taipei City 235, Taiwan
| | - Kuo Cheng Lu
- Graduate Institute of Clinical Medicine, College of Medicine, Taipei Medical University, Taipei 11031, Taiwan.,Division of Nephrology, Department of Medicine, Fu Jen Catholic University Hospital, School of Medicine, Fu Jen Catholic University, New Taipei City 242, Taiwan
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21
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Tabecka-Lonczynska A, Mytych J, Solek P, Kowalewski MP, Koziorowski M. Seasonal expression of insulin-like growth factor 1 (IGF-1), its receptor IGF-1R and klotho in testis and epididymis of the European bison (Bison bonasus, Linnaeus 1758). Theriogenology 2018; 126:199-205. [PMID: 30579142 DOI: 10.1016/j.theriogenology.2018.12.016] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2018] [Accepted: 12/04/2018] [Indexed: 12/12/2022]
Abstract
The European bisons are the largest mammals of Europe that are still in danger of extinction. The species conservation is associated with their continuous reproduction, and bisons are characterized by the well-pronounced seasonality of reproductive processes. However, the exact mechanisms regulating their reproduction still remain unknown. Our previous studies indicated the involvement of some of the growth factors in the regulation of male seasonal reproductive activities in bison, showing expression patterns that seemed to be regulated by the length of the daylight. In the present study, using RT-PCR and Western blot approaches, we verified the expression and possible relationship between the insulin-like growth factor (IGF-1), its receptor (IGF-1R), and klotho in testis and epididymis of the European bison in pre- and post-reproductive periods, i.e., in June and in December. The observed expression of IGF-1 and IGF-1R mRNA in testis and epididymis was higher in June than in December. At the same time, klotho mRNA expression in both testis and epididymis did not differ between the analyzed seasons. However, along with the higher levels of IGF-1R protein observed in June, klotho protein levels for the membrane form and for the secrete form were higher in December than in June. Finally, the messenger and protein expression profiles presented herein indicate the importance of both the IGF-system and klotho in reproductive processes in the European bison, implying their involvement in the regulation of seasonal testicular activity in males of this threatened species.
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Affiliation(s)
- Anna Tabecka-Lonczynska
- Department of Animal Physiology and Reproduction, Faculty of Biotechnology, University of Rzeszow, Werynia 502, 36-100, Kolbuszowa, Poland.
| | - Jennifer Mytych
- Department of Animal Physiology and Reproduction, Faculty of Biotechnology, University of Rzeszow, Werynia 502, 36-100, Kolbuszowa, Poland
| | - Przemyslaw Solek
- Department of Animal Physiology and Reproduction, Faculty of Biotechnology, University of Rzeszow, Werynia 502, 36-100, Kolbuszowa, Poland
| | - Mariusz P Kowalewski
- Institute of Veterinary Anatomy, Vetsuisse Faculty, University of Zurich, Zurich, Winterthurerstr. 260, CH-8057, Switzerland
| | - Marek Koziorowski
- Department of Animal Physiology and Reproduction, Faculty of Biotechnology, University of Rzeszow, Werynia 502, 36-100, Kolbuszowa, Poland
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Sato T, Komaba H, Nagatani T, Watanabe T, Kishida Y, Fukagawa M. The Pituitary Is a Candidate Organ That Modulates Circulating Klotho Levels. J Endocr Soc 2018; 3:52-61. [PMID: 30697600 PMCID: PMC6344344 DOI: 10.1210/js.2018-00223] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/24/2018] [Accepted: 11/09/2018] [Indexed: 11/19/2022] Open
Abstract
Context The antiaging protein Klotho is shed and released into the blood stream (soluble Klotho). Growth hormone (GH) is considered an active Klotho regulator, because growth retardation is described in Klotho-deficient mice. The origin of circulating Klotho is, however, not fully understood. Objectives Our objective was to analyze a possible role of the pituitary in regulating soluble Klotho in patients with pituitary adenomas. Patients, Design, and Setting We analyzed serum levels of soluble Klotho, GH, and insulin-like growth factor 1 (IGF-1) from 21 consecutive patients in our center with pituitary tumor, 7 with GH-producing adenomas (GHomas), and 14 with non–GH-producing pituitary adenomas (non-GHomas), before and after endoscopic transsphenoidal surgery (eTSS). Main Outcome Measure Soluble Klotho levels were determined by ELISA with antihuman Klotho antibodies. Results Baseline soluble Klotho levels in all patients, those with GHoma and those with non-GHoma, were 542 (median) (interquartile range: 403, 652), 1083 (425, 1213), and 525 (399, 590), respectively. A drastic reduction in Klotho levels was identified in those with GHoma, accompanied by decreases in GH and IGF-1 levels, after eTSS. Interestingly, patients with non-GHoma had significant declines in soluble Klotho without any significant changes in GH levels. Moreover, an oral glucose tolerance test revealed that soluble Klotho levels decreased, whereas a paradoxical GH peak was observed after glucose intake in a patient with GHoma. Conclusions Our data suggest that the pituitary may be a key organ that regulates circulating Klotho concentrations, implying that the pituitary possibly controls circulating Klotho through GH-dependent and/or GH-independent mechanisms.
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Affiliation(s)
- Tetsuhiko Sato
- General Internal Medicine, Nagoya Daini Red Cross Hospital, Nagoya, Japan
| | - Hirotaka Komaba
- Division of Nephrology, Endocrinology, and Metabolism, Tokai University School of Medicine, Isehara, Japan
| | - Tetsuya Nagatani
- Division of Neurosurgery, Nagoya Daini Red Cross Hospital, Nagoya, Japan
| | - Tadashi Watanabe
- Division of Neurosurgery, Nagoya Daini Red Cross Hospital, Nagoya, Japan
| | - Yugo Kishida
- Division of Neurosurgery, Nagoya Daini Red Cross Hospital, Nagoya, Japan
| | - Masafumi Fukagawa
- Division of Nephrology, Endocrinology, and Metabolism, Tokai University School of Medicine, Isehara, Japan
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Lekawanvijit S. Cardiotoxicity of Uremic Toxins: A Driver of Cardiorenal Syndrome. Toxins (Basel) 2018; 10:toxins10090352. [PMID: 30200452 PMCID: PMC6162485 DOI: 10.3390/toxins10090352] [Citation(s) in RCA: 58] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2018] [Revised: 08/19/2018] [Accepted: 08/30/2018] [Indexed: 02/07/2023] Open
Abstract
Cardiovascular disease (CVD) is highly prevalent in the setting of chronic kidney disease (CKD). Such coexistence of CVD and CKD—the so-called “cardiorenal or renocardiac syndrome”—contributes to exponentially increased risk of cardiovascular (CV) mortality. Uremic cardiomyopathy is a characteristic cardiac pathology commonly found in CKD. CKD patients are also predisposed to heart rhythm disorders especially atrial fibrillation. Traditional CV risk factors as well as known CKD-associated CV risk factors such as anemia are insufficient to explain CV complications in the CKD population. Accumulation of uremic retention solutes is a hallmark of impaired renal excretory function. Many of them have been considered inert solutes until their biological toxicity is unraveled and they become accepted as “uremic toxins”. Direct cardiotoxicity of uremic toxins has been increasingly demonstrated in recent years. This review offers a mechanistic insight into the pathological cardiac remodeling and dysfunction contributed by uremic toxins with a main focus on fibroblastic growth factor-23, an emerging toxin playing a central role in the chronic kidney disease–mineral bone disorder, and the two most investigated non-dialyzable protein-bound uremic toxins, indoxyl sulfate and p-cresyl sulfate. Potential therapeutic strategies that could address these toxins and their relevant mediated pathways since pre-dialysis stages are also discussed.
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Affiliation(s)
- Suree Lekawanvijit
- Department of Pathology, Faculty of Medicine, Chiang Mai University, 110 Intawaroros Rd, Sribhoom, Chiang Mai 50200, Thailand.
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Hernando N, Wagner CA. Mechanisms and Regulation of Intestinal Phosphate Absorption. Compr Physiol 2018; 8:1065-1090. [PMID: 29978897 DOI: 10.1002/cphy.c170024] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
States of hypo- and hyperphosphatemia have deleterious consequences including rickets/osteomalacia and renal/cardiovascular disease, respectively. Therefore, the maintenance of appropriate plasma levels of phosphate is an essential requirement for health. This control is executed by the collaborative action of intestine and kidney whose capacities to (re)absorb phosphate are regulated by a number of hormonal and metabolic factors, among them parathyroid hormone, fibroblast growth factor 23, 1,25(OH)2 vitamin D3 , and dietary phosphate. The molecular mechanisms responsible for the transepithelial transport of phosphate across enterocytes are only partially understood. Indeed, whereas renal reabsorption entirely relies on well-characterized active transport mechanisms of phosphate across the renal proximal epithelia, intestinal absorption proceeds via active and passive mechanisms, with the molecular identity of the passive component still unknown. The active absorption of phosphate depends mostly on the activity and expression of the sodium-dependent phosphate cotransporter NaPi-IIb (SLC34A2), which is highly regulated by many of the factors, mentioned earlier. Physiologically, the contribution of NaPi-IIb to the maintenance of phosphate balance appears to be mostly relevant during periods of low phosphate availability. Therefore, its role in individuals living in industrialized societies with high phosphate intake is probably less relevant. Importantly, small increases in plasma phosphate, even within normal range, associate with higher risk of cardiovascular disease. Therefore, therapeutic approaches to treat hyperphosphatemia, including dietary phosphate restriction and phosphate binders, aim at reducing intestinal absorption. Here we review the current state of research in the field. © 2017 American Physiological Society. Compr Physiol 8:1065-1090, 2018.
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Affiliation(s)
- Nati Hernando
- National Center for Competence in Research NCCR Kidney.CH, Institute of Physiology, University Zurich-Irchel, Zurich, Switzerland
| | - Carsten A Wagner
- National Center for Competence in Research NCCR Kidney.CH, Institute of Physiology, University Zurich-Irchel, Zurich, Switzerland
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Interrelated role of Klotho and calcium-sensing receptor in parathyroid hormone synthesis and parathyroid hyperplasia. Proc Natl Acad Sci U S A 2018; 115:E3749-E3758. [PMID: 29618612 DOI: 10.1073/pnas.1717754115] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
The pathogenesis of parathyroid gland hyperplasia is poorly understood, and a better understanding is essential if there is to be improvement over the current strategies for prevention and treatment of secondary hyperparathyroidism. Here we investigate the specific role of Klotho expressed in the parathyroid glands (PTGs) in mediating parathyroid hormone (PTH) and serum calcium homeostasis, as well as the potential interaction between calcium-sensing receptor (CaSR) and Klotho. We generated mouse strains with PTG-specific deletion of Klotho and CaSR and dual deletion of both genes. We show that ablating CaSR in the PTGs increases PTH synthesis, that Klotho has a pivotal role in suppressing PTH in the absence of CaSR, and that CaSR together with Klotho regulates PTH biosynthesis and PTG growth. We utilized the tdTomato gene in our mice to visualize and collect PTGs to reveal an inhibitory function of Klotho on PTG cell proliferation. Chronic hypocalcemia and ex vivo PTG culture demonstrated an independent role for Klotho in mediating PTH secretion. Moreover, we identify an interaction between PTG-expressed CaSR and Klotho. These findings reveal essential and interrelated functions for CaSR and Klotho during parathyroid hyperplasia.
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26
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Bouksila M, Kaabachi W, Mrad M, Smaoui W, El Kateb EC, Zouaghi MK, Hamzaoui K, Bahlous A. FGF 23, PTH and vitamin D status in end stage renal disease patients affected by VDR Fok I and Bsm I variants. Clin Biochem 2018; 54:42-50. [DOI: 10.1016/j.clinbiochem.2018.02.009] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2017] [Revised: 02/13/2018] [Accepted: 02/15/2018] [Indexed: 02/07/2023]
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Parathyroidectomy in patients with chronic kidney disease: Impacts of different techniques on the biochemical and clinical evolution of secondary hyperparathyroidism. Surgery 2018; 163:381-387. [DOI: 10.1016/j.surg.2017.09.005] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2017] [Revised: 08/29/2017] [Accepted: 09/13/2017] [Indexed: 11/19/2022]
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Olauson H, Mencke R, Hillebrands JL, Larsson TE. Tissue expression and source of circulating αKlotho. Bone 2017; 100:19-35. [PMID: 28323144 DOI: 10.1016/j.bone.2017.03.043] [Citation(s) in RCA: 68] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/08/2016] [Revised: 03/15/2017] [Accepted: 03/16/2017] [Indexed: 12/16/2022]
Abstract
αKlotho (Klotho), a type I transmembrane protein and a coreceptor for Fibroblast Growth Factor-23, was initially thought to be expressed only in a limited number of tissues, most importantly the kidney, parathyroid gland and choroid plexus. Emerging data may suggest a more ubiquitous Klotho expression pattern which has prompted reevaluation of the restricted Klotho paradigm. Herein we systematically review the evidence for Klotho expression in various tissues and cell types in humans and other mammals, and discuss potential reasons behind existing conflicting data. Based on current literature and tissue expression atlases, we propose a classification of tissues into high, intermediate and low/absent Klotho expression. The functional relevance of Klotho in organs with low expression levels remain uncertain and there is currently limited data on a role for membrane-bound Klotho outside the kidney. Finally, we review the evidence for the tissue source of soluble Klotho, and conclude that the kidney is likely to be the principal source of circulating Klotho in physiology.
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Affiliation(s)
- Hannes Olauson
- Division of Renal Medicine, Department of Clinical Science, Intervention and Technology, Karolinska Institutet, Stockholm, Sweden.
| | - Rik Mencke
- Division of Pathology, Department of Pathology and Medical Biology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Jan-Luuk Hillebrands
- Division of Pathology, Department of Pathology and Medical Biology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Tobias E Larsson
- Division of Renal Medicine, Department of Clinical Science, Intervention and Technology, Karolinska Institutet, Stockholm, Sweden
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Neyra JA, Hu MC. Potential application of klotho in human chronic kidney disease. Bone 2017; 100:41-49. [PMID: 28115282 PMCID: PMC5474175 DOI: 10.1016/j.bone.2017.01.017] [Citation(s) in RCA: 78] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/01/2016] [Revised: 01/18/2017] [Accepted: 01/18/2017] [Indexed: 01/13/2023]
Abstract
The extracellular domain of transmembrane alpha-Klotho (αKlotho, hereinafter simply called Klotho) is cleaved by secretases and released into the circulation as soluble Klotho. Soluble Klotho in the circulation starts to decline early in chronic kidney disease (CKD) stage 2 and urinary Klotho possibly even earlier in CKD stage 1. Therefore soluble Klotho could serve as an early and sensitive marker of kidney function decline. Moreover, preclinical animal data support Klotho deficiency is not just merely a biomarker, but a pathogenic factor for CKD progression and extrarenal CKD complications including cardiovascular disease and disturbed mineral metabolism. Prevention of Klotho decline, re-activation of endogenous Klotho production or supplementation of exogenous Klotho are all associated with attenuation of renal fibrosis, retardation of CKD progression, improvement of mineral metabolism, amelioration of cardiomyopathy, and alleviation of vascular calcification in CKD. Therefore Klotho is not only a diagnostic and/or prognostic marker for CKD, but the treatment of Klotho deficiency may be a promising strategy to prevent, retard, and decrease the burden of comorbidity in CKD.
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Affiliation(s)
- Javier A Neyra
- Department of Internal Medicine, University of Texas Southwestern Medical Center, USA; Charles and Jane Pak Center for Mineral Metabolism and Clinical Research, University of Texas Southwestern Medical Center, USA
| | - Ming Chang Hu
- Department of Internal Medicine, University of Texas Southwestern Medical Center, USA; Charles and Jane Pak Center for Mineral Metabolism and Clinical Research, University of Texas Southwestern Medical Center, USA.
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Ter Braake AD, Shanahan CM, de Baaij JHF. Magnesium Counteracts Vascular Calcification: Passive Interference or Active Modulation? Arterioscler Thromb Vasc Biol 2017; 37:1431-1445. [PMID: 28663256 DOI: 10.1161/atvbaha.117.309182] [Citation(s) in RCA: 73] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2017] [Accepted: 06/15/2017] [Indexed: 12/24/2022]
Abstract
Over the last decade, an increasing number of studies report a close relationship between serum magnesium concentration and cardiovascular disease risk in the general population. In end-stage renal disease, an association was found between serum magnesium and survival. Hypomagnesemia was identified as a strong predictor for cardiovascular disease in these patients. A substantial body of in vitro and in vivo studies has identified a protective role for magnesium in vascular calcification. However, the precise mechanisms and its contribution to cardiovascular protection remain unclear. There are currently 2 leading hypotheses: first, magnesium may bind phosphate and delay calcium phosphate crystal growth in the circulation, thereby passively interfering with calcium phosphate deposition in the vessel wall. Second, magnesium may regulate vascular smooth muscle cell transdifferentiation toward an osteogenic phenotype by active cellular modulation of factors associated with calcification. Here, the data supporting these major hypotheses are reviewed. The literature supports both a passive inorganic phosphate-buffering role reducing hydroxyapatite formation and an active cell-mediated role, directly targeting vascular smooth muscle transdifferentiation. However, current evidence relies on basic experimental designs that are often insufficient to delineate the underlying mechanisms. The field requires more advanced experimental design, including determination of intracellular magnesium concentrations and the identification of the molecular players that regulate magnesium concentrations in vascular smooth muscle cells.
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Affiliation(s)
- Anique D Ter Braake
- From the Department of Physiology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, The Netherlands (A.D.t.B., J.H.F.d.B.); Cardiovascular Division, BHF Centre of Research Excellence, James Black Centre, King's College, London, United Kingdom (C.M.S.); and Department of Physiology, Anatomy and Genetics, University of Oxford, United Kingdom (J.H.F.d.B.)
| | - Catherine M Shanahan
- From the Department of Physiology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, The Netherlands (A.D.t.B., J.H.F.d.B.); Cardiovascular Division, BHF Centre of Research Excellence, James Black Centre, King's College, London, United Kingdom (C.M.S.); and Department of Physiology, Anatomy and Genetics, University of Oxford, United Kingdom (J.H.F.d.B.)
| | - Jeroen H F de Baaij
- From the Department of Physiology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, The Netherlands (A.D.t.B., J.H.F.d.B.); Cardiovascular Division, BHF Centre of Research Excellence, James Black Centre, King's College, London, United Kingdom (C.M.S.); and Department of Physiology, Anatomy and Genetics, University of Oxford, United Kingdom (J.H.F.d.B.).
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31
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Bleskestad IH, Thorsen IS, Jonsson G, Skadberg Ø, Gøransson LG. The impact of calcineurin inhibitors on neutrophil gelatinase-associated lipocalin and fibroblast growth factor 23 in long-term kidney transplant patients. Clin Transplant 2017; 31. [PMID: 28523792 DOI: 10.1111/ctr.13015] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/15/2017] [Indexed: 12/20/2022]
Abstract
BACKGROUND Neutrophil gelatinase-associated lipocalin (NGAL), a protein with bacteriostatic functions rapidly excreted from stimulated or damaged epithelial cells, is elevated in acute and chronic kidney disease. A calcineurin dependent signaling pathway for fibroblast growth factor 23 (FGF23) has been revealed, but the effect of calcineurin inhibitors (CNIs) on the levels of NGAL and markers of mineral metabolism in long-term kidney transplant patients has not been explored. METHODS In a cross-sectional study, 39 patients who received a first kidney transplant more than 10 years ago were split into two groups based on whether (n=28) or not (n=11) they used CNIs. Only patients with well-functioning grafts defined as an estimated glomerular filtration rate ≥45 mL/min per 1.73 m2 were included. RESULTS The median levels of NGAL, intact parathyroid hormone (iPTH), and iFGF23 were significantly higher in CNI users vs CNI nonusers, 167.0 (134.0-235.0) ng/mL vs 105.0 (91.3-117.0) ng/mL, P<.001, 13.8 (10.0-17.3) pmol/L vs 8.4 (6.4-9.9) pmol/L, P=.003, and 81.6 (56.4-116.5) pg/mL vs 61.8 (43.3-72.1) pg/mL, P=.04 respectively. CONCLUSIONS The median levels of iFGF23 were higher in CNI users compared to CNI nonusers giving support to the notion of a CNI induced FGF23 resistance in the parathyroid. The net result of CNIs side effects needs to be further explored.
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Affiliation(s)
| | - Inga Strand Thorsen
- Department of Internal Medicine, Stavanger University Hospital, Stavanger, Norway
| | - Grete Jonsson
- Department of Medical Biochemistry, Stavanger University Hospital, Stavanger, Norway
| | - Øyvind Skadberg
- Department of Medical Biochemistry, Stavanger University Hospital, Stavanger, Norway
| | - Lasse Gunnar Gøransson
- Department of Internal Medicine, Stavanger University Hospital, Stavanger, Norway.,Department of Clinical Medicine (K1), University of Bergen, Bergen, Norway
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Portillo MR, Rodríguez-Ortiz ME. Secondary Hyperparthyroidism: Pathogenesis, Diagnosis, Preventive and Therapeutic Strategies. Rev Endocr Metab Disord 2017; 18:79-95. [PMID: 28378123 DOI: 10.1007/s11154-017-9421-4] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Uremic secondary hyperparathyroidism is a multifactorial and complex disease often present in advanced stages of chronic kidney disease. The accumulation of phosphate, the increased FGF23 levels, the reduction in active vitamin D production, and the tendency to hypocalcemia are persistent stimuli for the development and progression of parathyroid hyperplasia with increased secretion of PTH. Parathyroid proliferation may become nodular mainly in cases of advanced hyperparathyroidism. The alterations in the regulation of mineral metabolism, the development of bone disease and extraosseous calcifications are essential components of chronic kidney disease-mineral and bone disorder and have been associated with negative outcomes. The management of hyperparathyroidism includes the correction of vitamin D deficiency and control of serum phosphorus and PTH without inducing hypercalcemia. An update of the leading therapeutic tools available for the prevention and clinical management of secondary hyperparathyroidism, its diagnosis, and the main mechanisms and factors involved in the pathogenesis of the disease will be described in this review.
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Affiliation(s)
- Mariano Rodríguez Portillo
- Nephrology Service, Instituto Maimónides de Investigación Biomédica de Córdoba (IMIBIC), Reina Sofía University Hospital/University of Córdoba, Avda. Menéndez Pidal, S/N, 14004, Córdoba, Spain.
- REDinREN, Madrid, Spain.
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Dalton GD, Xie J, An SW, Huang CL. New Insights into the Mechanism of Action of Soluble Klotho. Front Endocrinol (Lausanne) 2017; 8:323. [PMID: 29250031 PMCID: PMC5715364 DOI: 10.3389/fendo.2017.00323] [Citation(s) in RCA: 121] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/01/2017] [Accepted: 11/02/2017] [Indexed: 12/31/2022] Open
Abstract
The klotho gene encodes a type I single-pass transmembrane protein that contains a large extracellular domain, a membrane spanning segment, and a short intracellular domain. Klotho protein exists in several forms including the full-length membrane form (mKl) and a soluble circulating form [soluble klotho (sKl)]. mKl complexes with fibroblast growth factor receptors to form coreceptors for FGF23, which allows it to participate in FGF23-mediated signal transduction and regulation of phosphate and calcium homeostasis. sKl is present in the blood, urine, and cerebrospinal fluid where it performs a multitude of functions including regulation of ion channels/transporters and growth factor signaling. How sKl exerts these pleiotropic functions is poorly understood. One hurdle in understanding sKl's mechanism of action as a "hormone" has been the inability to identify a receptor that mediates its effects. In the body, the kidneys are a major source of sKl and sKl levels decline during renal disease. sKl deficiency in chronic kidney disease makes the heart susceptible to stress-induced injury. Here, we summarize the current knowledge of mKl's mechanism of action, the mechanistic basis of sKl's protective, FGF23-independent effects on the heart, and provide new insights into the mechanism of action of sKl focusing on recent findings that sKl binds sialogangliosides in membrane lipid rafts to regulate growth factor signaling.
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Affiliation(s)
- George D. Dalton
- Department of Medicine, Division of Gastroenterology, Duke University Medical Center, Durham, NC, United States
| | - Jian Xie
- Department of Internal Medicine, Division of Nephrology and Hypertension, University of Iowa Carver College of Medicine, Iowa City, IA, United States
| | - Sung-Wan An
- Department of Internal Medicine, Division of Nephrology and Hypertension, University of Iowa Carver College of Medicine, Iowa City, IA, United States
| | - Chou-Long Huang
- Department of Internal Medicine, Division of Nephrology and Hypertension, University of Iowa Carver College of Medicine, Iowa City, IA, United States
- *Correspondence: Chou-Long Huang,
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Mytych J, Wos I, Solek P, Koziorowski M. Protective role of klotho protein on epithelial cells upon co-culture with activated or senescent monocytes. Exp Cell Res 2016; 350:358-367. [PMID: 28011195 DOI: 10.1016/j.yexcr.2016.12.013] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2016] [Revised: 12/13/2016] [Accepted: 12/20/2016] [Indexed: 12/13/2022]
Abstract
Monocytes ensure proper functioning and maintenance of epithelial cells, while good condition of monocytes is a key factor of these interactions. Although, it was shown that in some circumstances, a population of altered monocytes may appear, there is no data regarding their effect on epithelial cells. In this study, using direct co-culture model with LPS-activated and Dox-induced senescent THP-1 monocytes, we reported for the first time ROS-induced DNA damage, reduced metabolic activity, proliferation inhibition and cell cycle arrest followed by p16-, p21- and p27-mediated DNA damage response pathways activation, premature senescence and apoptosis induction in HeLa cells. Also, we show that klotho protein possessing anti-aging and anti-inflammatory characteristics reduced cytotoxic and genotoxic events by inhibition of insulin/IGF-IR and downregulation of TRF1 and TRF2 proteins. Therefore, klotho protein could be considered as a protective factor against changes caused by altered monocytes in epithelial cells.
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Affiliation(s)
- Jennifer Mytych
- Institute of Applied Biotechnology and Basic Sciences, University of Rzeszow, Werynia 502, 36-100 Kolbuszowa, Poland; Centre of Applied Biotechnology and Basic Sciences, University of Rzeszow, Werynia 502, 36-100 Kolbuszowa, Poland.
| | - Izabela Wos
- Institute of Applied Biotechnology and Basic Sciences, University of Rzeszow, Werynia 502, 36-100 Kolbuszowa, Poland; Centre of Applied Biotechnology and Basic Sciences, University of Rzeszow, Werynia 502, 36-100 Kolbuszowa, Poland
| | - Przemyslaw Solek
- Institute of Applied Biotechnology and Basic Sciences, University of Rzeszow, Werynia 502, 36-100 Kolbuszowa, Poland; Centre of Applied Biotechnology and Basic Sciences, University of Rzeszow, Werynia 502, 36-100 Kolbuszowa, Poland
| | - Marek Koziorowski
- Institute of Applied Biotechnology and Basic Sciences, University of Rzeszow, Werynia 502, 36-100 Kolbuszowa, Poland; Centre of Applied Biotechnology and Basic Sciences, University of Rzeszow, Werynia 502, 36-100 Kolbuszowa, Poland
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Yu T, Yang Y, Liu Y, Zhang Y, Xu H, Li M, Ponnusamy M, Wang K, Wang JX, Li PF. A FGFR1 inhibitor patent review: progress since 2010. Expert Opin Ther Pat 2016; 27:439-454. [PMID: 27976968 DOI: 10.1080/13543776.2017.1272574] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
INTRODUCTION FGFR1 is a well known molecular target for anticancer therapy. Many studies have proved that the regulation of FGFR1 activity is a promising therapeutic approach to treat a series of cancers. Therefore, the development of potent inhibitors has consequently become a key focus in the present drug discovery, and it is encouraging that several highly selective FGFR1 inhibitors have been identified from various sources in recent years. Areas covered: This article reviews patents and patent applications related to selective FGFR1 inhibitors published from 2010 to 2016. This summary highlights about 15 patents from different pharmaceutical companies and academic research groups. We used Baidu and NCBI search engines to find relevant patents as a search term. Expert opinion: In the past few years, considerable progress has been made in the identification and development of selective FGFR1 inhibitors in use. At present, at least 10 inhibitors of FGFR1 are in clinical trials, and several agents have shown encouraging results under experimental conditions. Given the fact that FGFR1 plays a crucial role in the regulation of cancer and other diseases, we hope that it will gain further attraction from pharmaceutical companies and encourage development of more novel, safe and efficient FGFR1 inhibitors in the future.
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Affiliation(s)
- Tao Yu
- a Institute for Translational Medicine , Qingdao University , Qingdao , People's Republic of China
| | - Yanyan Yang
- a Institute for Translational Medicine , Qingdao University , Qingdao , People's Republic of China
| | - Yan Liu
- b Food and Drug Administration of Linyi City , Hedong District Branch , Linyi , People's Republic of China
| | - Yinfeng Zhang
- a Institute for Translational Medicine , Qingdao University , Qingdao , People's Republic of China
| | - Hong Xu
- c Department of Orthodontics , Affiliated Hospital of Qingdao University , People's Republic of China
| | - Mengpeng Li
- a Institute for Translational Medicine , Qingdao University , Qingdao , People's Republic of China
| | - Murugavel Ponnusamy
- a Institute for Translational Medicine , Qingdao University , Qingdao , People's Republic of China
| | - Kun Wang
- a Institute for Translational Medicine , Qingdao University , Qingdao , People's Republic of China
| | - Jian-Xun Wang
- a Institute for Translational Medicine , Qingdao University , Qingdao , People's Republic of China
| | - Pei-Feng Li
- a Institute for Translational Medicine , Qingdao University , Qingdao , People's Republic of China
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Abstract
Calcium is an important ion in cell signaling, hormone regulation, and bone health. Its regulation is complex and intimately connected to that of phosphate homeostasis. Both ions are maintained at appropriate levels to maintain the extracellular to intracellular gradients, allow for mineralization of bone, and to prevent extra skeletal and urinary calcification. The homeostasis involves the target organs intestine, parathyroid glands, kidney, and bone. Multiple hormones converge to regulate the extracellular calcium level: parathyroid hormone, vitamin D (principally 25(OH)D or 1,25(OH)2D), fibroblast growth factor 23, and α-klotho. Fine regulation of calcium homeostasis occurs in the thick ascending limb and collecting tubule segments via actions of the calcium sensing receptor and several channels/transporters. The kidney participates in homeostatic loops with bone, intestine, and parathyroid glands. Initially in the course of progressive kidney disease, the homeostatic response maintains serum levels of calcium and phosphorus in the desired range, and maintains neutral balance. However, once the kidneys are no longer able to appropriately respond to hormones and excrete calcium and phosphate, positive balance ensues leading to adverse cardiac and skeletal abnormalities. © 2016 American Physiological Society. Compr Physiol 6:1781-1800, 2016.
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Affiliation(s)
- Sharon M Moe
- Division of Nephrology, Indiana University School of Medicine, Roudebush Veterans Administration Medical Center, Indianapolis, Indiana.,Section of Nephrology, Roudebush Veterans Administration Medical Center, Indianapolis, Indiana
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Abstract
Fibroblast growth factor-23 (FGF23) is a bone-derived hormone known to suppress phosphate reabsorption and vitamin D hormone production in the kidney. Klotho was originally discovered as an anti-aging factor, but the functional role of Klotho is still a controversial issue. Three major functions have been proposed, a hormonal function of soluble Klotho, an enzymatic function as glycosidase, and the function as an obligatory co-receptor for FGF23 signaling. The purpose of this review is to highlight the recent advances in the area of FGF23 and Klotho signaling in the kidney, in the parathyroid gland, in the cardiovascular system, in bone, and in the central nervous system. During recent years, major new functions of FGF23 and Klotho have been discovered in these organ systems. Based on these novel findings, FGF23 has emerged as a pleiotropic endocrine and auto-/paracrine factor influencing not only mineral metabolism but also cardiovascular function.
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Abstract
Alpha-Klotho (αKlotho) protein is encoded by the gene, Klotho, and functions as a coreceptor for endocrine fibroblast growth factor-23. The extracellular domain of αKlotho is cleaved by secretases and released into the circulation where it is called soluble αKlotho. Soluble αKlotho in the circulation starts to decline in chronic kidney disease (CKD) stage 2 and urinary αKlotho in even earlier CKD stage 1. Therefore soluble αKlotho is an early and sensitive marker of decline in kidney function. Preclinical data from numerous animal experiments support αKlotho deficiency as a pathogenic factor for CKD progression and extrarenal CKD complications including cardiac and vascular disease, hyperparathyroidism, and disturbed mineral metabolism. αKlotho deficiency induces cell senescence and renders cells susceptible to apoptosis induced by a variety of cellular insults including oxidative stress. αKlotho deficiency also leads to defective autophagy and angiogenesis and promotes fibrosis in the kidney and heart. Most importantly, prevention of αKlotho decline, upregulation of endogenous αKlotho production, or direct supplementation of soluble αKlotho are all associated with attenuation of renal fibrosis, retardation of CKD progression, improvement of mineral metabolism, amelioration of cardiac function and morphometry, and alleviation of vascular calcification in CKD. Therefore in rodents, αKlotho is not only a diagnostic and prognostic marker for CKD but the enhancement of endogenous or supplement of exogenous αKlotho are promising therapeutic strategies to prevent, retard, and decrease the comorbidity burden of CKD.
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Affiliation(s)
- J A Neyra
- University of Texas Southwestern Medical Center, Dallas, TX, United States; Charles and Jane Pak Center for Mineral Metabolism and Clinical Research, University of Texas Southwestern Medical Center, Dallas, TX, United States
| | - M C Hu
- University of Texas Southwestern Medical Center, Dallas, TX, United States; Charles and Jane Pak Center for Mineral Metabolism and Clinical Research, University of Texas Southwestern Medical Center, Dallas, TX, United States.
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Abstract
PURPOSE OF REVIEW Mineral and bone disorders are common problems in organ transplant recipients. Successful transplantation solves many aspects of abnormal mineral and bone metabolism, but the degree of improvement is frequently incomplete. Posttransplant bone disease can affect long-term outcomes as well as increase the likelihood of fracture. In this article, we reviewed the major posttransplant bone diseases and recent advances in treatment strategies. RECENT FINDINGS Pretransplant bone disease and immunosuppressants are important risk factors for posttransplant bone disease. Corticosteroid withdrawal may result in minimal or no protection against fractures, with increased risk for acute rejection. Vitamin D analogue and bisphosphonate are frequently used to prevent and treat posttransplant osteoporosis. Posttransplant hyperparathyroidism increases the risk for all-cause mortality and graft loss, but not major cardiovascular events. Cinacalcet was well tolerated and effectively controlled hypercalcemic hyperparathyroidism; however, it did not improve bone mineral density and discontinuation led to parathyroid hormone rebound. Six-month paricalcitol supplementation reduced parathyroid hormone levels and attenuated bone remodeling and mineral loss in case of posttransplant hyperparathyroidism. SUMMARY Posttransplant bone diseases present in various forms, including osteoporosis, hyperparathyroidism, adynamic bone disease, and osteonecrosis. Prophylactic and therapeutic approaches to both pretransplant and posttransplant periods should be considered.
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Affiliation(s)
- Hee Jung Jeon
- aDepartment of Internal Medicine, Hallym University Kangdong Sacred Heart Hospital, Seoul, Republic of Korea bDivision of Nephrology, Department of Internal Medicine, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea cTransplantation Center, Seoul National University Hospital, Seoul, Republic of Korea *Hee Jung Jeon and Hyosang Kim contributed equally to the writing of this article
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Malyszko J, Koc-Zorawska E, Matuszkiewicz-Rowinska J, Malyszko J. FGF23 and Klotho in relation to markers of endothelial dysfunction in kidney transplant recipients. Transplant Proc 2015; 46:2647-50. [PMID: 25380886 DOI: 10.1016/j.transproceed.2014.09.015] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
BACKGROUND Fibroblast growth factor (FGF) 23 is a newly discovered member of the FGF family. Klotho is a cofactor of FGF23. Activation of the FGF23-Klotho system is responsible for negative phosphate balance. In addition, FGF23 appears to be a risk factor for cardiovascular complications. The aim of this study was to assess levels of FGF23 and Klotho in stable kidney transplant recipients on triple immunosuppressive therapy in relation to comorbidities and markers endothelial dysfunction. Healthy volunteers served as a control group. METHODS Hemoglobin, urea, and creatinine were studied with the use of standard laboratory methods in the hospital central laboratory. We assessed FGF23 and Klotho, markers of endothelial function/injury von Willebrand factor (vWF), intercellular adhesion molecule (ICAM), vascular cell adhesion molecule (VCAM), and interleukin (IL) 6, N-terminal pro-B-type natriuretic peptide (NT-proBNP) and copeptin with the use of commercially available assays. RESULTS FGF23 was significantly higher and Klotho significantly lower in kidney transplant recipients compared with healthy volunteers. FGF23 correlated with copeptin (r = 0.28; P < .05), IL-6 (r = 0.39; P < .01), VCAM (r = 0.36; P < .01), time after transplantation (r = 0.31; P < .05), platelet count (r = 0.31; P < .05), mean corpuscular volume (r = -0.40; P < .01), and phosphate (r = 0.31; P < .05). Klotho correlated with NT-proBNP (r = 0.38; P < .01), vWF (r = -0.26; P < .05), calcium (r = -0.39; P < .01), and age (r = 0.45; P < .001). FGF23 was significantly higher and Klotho significantly lower in patients with estimated glomerular filtration rate (eGFR) >60 mL/min compared with patients with eGFR <60 mL/min. CONCLUSIONS Disturbances in the FGF23-Klotho system appeared to be related to the endothelial cell injury. Thus they are involved not only in pathogenesis of the metabolic bone disease but also in cardiovascular complications, particularly in kidney disease.
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Affiliation(s)
- Jolanta Malyszko
- 2nd Department of Nephrology, Medical University, Bialystok, Poland.
| | - E Koc-Zorawska
- 2nd Department of Nephrology, Medical University, Bialystok, Poland
| | - J Matuszkiewicz-Rowinska
- Department of Nephrology, Internal Medicine and Dialysis Therapy, Medical University, Warsaw, Poland
| | - Jacek Malyszko
- 2nd Department of Nephrology, Medical University, Bialystok, Poland
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Lim K, Groen A, Molostvov G, Lu T, Lilley KS, Snead D, James S, Wilkinson IB, Ting S, Hsiao LL, Hiemstra TF, Zehnder D. α-Klotho Expression in Human Tissues. J Clin Endocrinol Metab 2015; 100:E1308-18. [PMID: 26280509 PMCID: PMC4596032 DOI: 10.1210/jc.2015-1800] [Citation(s) in RCA: 128] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
CONTEXT α-Klotho has emerged as a powerful regulator of the aging process. To date, the expression profile of α-Klotho in human tissues is unknown, and its existence in some human tissue types is subject to much controversy. OBJECTIVE This is the first study to characterize systemwide tissue expression of transmembrane α-Klotho in humans. We have employed next-generation targeted proteomic analysis using parallel reaction monitoring in parallel with conventional antibody-based methods to determine the expression and spatial distribution of human α-Klotho expression in health. RESULTS The distribution of α-Klotho in human tissues from various organ systems, including arterial, epithelial, endocrine, reproductive, and neuronal tissues, was first identified by immunohistochemistry. Kidney tissues showed strong α-Klotho expression, whereas liver did not reveal a detectable signal. These results were next confirmed by Western blotting of both whole tissues and primary cells. To validate our antibody-based results, α-Klotho-expressing tissues were subjected to parallel reaction monitoring mass spectrometry (data deposited at ProteomeXchange, PXD002775) identifying peptides specific for the full-length, transmembrane α-Klotho isoform. CONCLUSIONS The data presented confirm α-Klotho expression in the kidney tubule and in the artery and provide evidence of α-Klotho expression across organ systems and cell types that has not previously been described in humans.
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Felsenfeld AJ, Levine BS, Rodriguez M. Pathophysiology of Calcium, Phosphorus, and Magnesium Dysregulation in Chronic Kidney Disease. Semin Dial 2015; 28:564-77. [DOI: 10.1111/sdi.12411] [Citation(s) in RCA: 89] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Affiliation(s)
- Arnold J. Felsenfeld
- Department of Medicine; VA Greater Los Angeles Healthcare System and the David Geffen School of Medicine at UCLA; Los Angeles California
| | - Barton S. Levine
- Department of Medicine; VA Greater Los Angeles Healthcare System and the David Geffen School of Medicine at UCLA; Los Angeles California
| | - Mariano Rodriguez
- Nephrology Service; IMIBIC; Hospital Universitario Reina Sofia; University of Cordoba; Cordoba Spain
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Tran L, Batech M, Rhee CM, Streja E, Kalantar-Zadeh K, Jacobsen SJ, Sim JJ. Serum phosphorus and association with anemia among a large diverse population with and without chronic kidney disease. Nephrol Dial Transplant 2015; 31:636-45. [PMID: 26254460 DOI: 10.1093/ndt/gfv297] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2015] [Accepted: 07/09/2015] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND We hypothesized that phosphorus has an effect on anemia in both normal kidney function and early chronic kidney disease (CKD). We sought to determine whether higher phosphorus levels are associated with anemia in a large diverse population without CKD and early CKD. METHODS This study is a historical population-based study within the Kaiser Permanente Southern California health system (1 January 1998 to 31 December 2013) among individuals aged 18 years and older with estimated glomerular filtration rate >30 mL/min/1.73 m(2) and measurements of serum phosphorus, creatinine and hemoglobin. Individuals were excluded if they had secondary causes of anemia. Odds ratio (OR) estimated for moderate anemia defined as hemoglobin <11 g/dL for both sexes. Mild anemia was defined as <12 g/dL (females) and <13 g/dL (males). RESULTS Among 155 974 individuals, 4.1% had moderate anemia and 12.9% had mild anemia. Serum phosphorus levels ≥3.5 mg/dL were associated with both mild and moderate anemia. Moderate anemia OR (95% confidence interval) was 1.16 (1.04-1.29) for every 0.5 mg/dL phosphorus increase and 1.26 (1.07-1.48) in the highest versus middle phosphorus tertile. Additional independent anemia risk factors, including female sex, Asian race, diabetes, low albumin and low iron saturation, were observed, but did not alter the anemia-phosphorus association. CONCLUSIONS Higher phosphorus levels were associated with a greater likelihood for anemia in a population with early CKD and normal kidney function. Phosphorus may be a biomarker for anemia and may affect aspects of hematopoiesis.
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Affiliation(s)
- Lac Tran
- Division of Nephrology and Hypertension, Kaiser Permanente Los Angeles Medical Center, Los Angeles, CA, USA
| | - Michael Batech
- Department of Research and Evaluation, Kaiser Permanente Southern California, Pasadena, CA, USA
| | - Connie M Rhee
- Division of Nephrology and Hypertension, University of California Irvine School of Medicine, University of California Irvine Medical Center, Irvine, CA, USA
| | - Elani Streja
- Division of Nephrology and Hypertension, University of California Irvine School of Medicine, University of California Irvine Medical Center, Irvine, CA, USA
| | - Kamyar Kalantar-Zadeh
- Division of Nephrology and Hypertension, University of California Irvine School of Medicine, University of California Irvine Medical Center, Irvine, CA, USA
| | - Steven J Jacobsen
- Department of Research and Evaluation, Kaiser Permanente Southern California, Pasadena, CA, USA
| | - John J Sim
- Division of Nephrology and Hypertension, Kaiser Permanente Los Angeles Medical Center, Los Angeles, CA, USA
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Olauson H, Vervloet MG, Cozzolino M, Massy ZA, Ureña Torres P, Larsson TE. New insights into the FGF23-Klotho axis. Semin Nephrol 2015; 34:586-97. [PMID: 25498378 DOI: 10.1016/j.semnephrol.2014.09.005] [Citation(s) in RCA: 62] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Abnormal mineral metabolism is a hallmark in patients with advanced chronic kidney disease (CKD). Hyperphosphatemia, and the homeostatic mechanisms controlling phosphate metabolism, have received particular attention over the past decade. The phosphate-regulating hormone fibroblast growth factor-23 (FGF23) was discovered through studies of rare hypophosphatemic disorders, whereas Klotho, which subsequently turned out to be a co-receptor for FGF23, was identified in a mouse model showing hyperphosphatemia and multiple aging-like traits. The FGF23-Klotho endocrine axis is a pivotal regulator of mineral metabolism. In CKD, early onset of Klotho deficiency contributes to renal FGF23 resistance and a maladaptive increase in circulating FGF23. FGF23 is an early biomarker of renal injury and increased FGF23 predicts adverse clinical outcomes, in particular cardiovascular disease. A paradigm of FGF23 excess and Klotho deficiency is proposed, in which FGF23 preferentially stimulates left ventricular hypertrophy, and loss of Klotho augments fibrosis, endothelial dysfunction, and vascular calcification. The clinical benefit of FGF23 and Klotho measurements remain uncertain, nevertheless, the FGF23-Klotho axis is a solid candidate for a novel diagnostic and therapeutic target in CKD.
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Affiliation(s)
- Hannes Olauson
- Division of Renal Medicine, Department of Clinical Science, Intervention and Technology, Karolinska Institutet, Stockholm, Sweden
| | - Marc G Vervloet
- Department of Nephrology, Institute for Cardiovascular Research, VU University Medical Center, Amsterdam, The Netherlands
| | - Mario Cozzolino
- Department of Health Sciences, University of Milan, Renal Division, San Paolo Hospital, Milan, Italy
| | - Ziad A Massy
- Inserm U-1088, Université de Picardie Jules Verne (UPJV), Amiens, France; Division of Nephrology, Ambroise Paré Hospital, Paris-Ile-de-France-Ouest University (Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)), Paris-Boulogne Billancourt, France
| | - Pablo Ureña Torres
- Service of Nephrology and Dialysis, Clinique du Landy and Department of Renal Physiology, Necker Hospital, University of Paris Descartes, Paris, France
| | - Tobias E Larsson
- Division of Renal Medicine, Department of Clinical Science, Intervention and Technology, Karolinska Institutet, Stockholm, Sweden; Department of Nephrology, Karolinska University Hospital, Stockholm, Sweden.
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Vervloet MG, Adema AY, Larsson TE, Massy ZA. The role of klotho on vascular calcification and endothelial function in chronic kidney disease. Semin Nephrol 2015; 34:578-85. [PMID: 25498377 DOI: 10.1016/j.semnephrol.2014.09.003] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Recent insights into novel roles of klotho in vascular biology make this primarily kidney-derived protein a possible candidate to form a link between chronic kidney disease and cardiovascular morbidity and mortality. Typical features of vascular dysfunction or structural abnormalities in the arterial wall are exacerbated in klotho-deficient states. Reported klotho functions include inhibition of local phosphate transport in vascular cells, phenotypic switches of vascular cellular elements into bone-forming cells, attenuation of matrix mineralization and calcification, and also preservation of endothelial functional properties and viability. To a large extent these insights rely on animal models of kidney or cardiovascular diseases. In this review the current state of knowledge on these issues is summarized, and we aim to provide a possible new perspective on cardiovascular disease in chronic kidney disease.
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Affiliation(s)
- Marc G Vervloet
- Department of Nephrology, VU University Medical Center, Amsterdam, The Netherlands; Institute for Cardiovascular Research VU (ICaR-VU), VU University Medical Center, Amsterdam, The Netherlands.
| | - Aaltje Y Adema
- Department of Nephrology, VU University Medical Center, Amsterdam, The Netherlands
| | - Tobias E Larsson
- Department of Clinical Science, Intervention and Technology, Renal Unit, Karolinska Institute, Stockholm, Sweden; Department of Nephrology, Karolinska University Hospital, Stockholm, Sweden
| | - Ziad A Massy
- Inserm U-1088, University of Picardie Jules verne (UPJV), Amiens, France; Division of Nephrology, Ambroise Paré Hospital, Paris-Ile-de-France-Ouest University (University of Versailles Saint Quentin (UVSQ)), Paris-Boulogne Billancourt, France
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Abstract
Traditionally, control of phosphorus in the body has been considered secondary to the tighter control of calcium by parathyroid hormone and vitamin D. However, over the past decade, substantial advances have been made in understanding the control of phosphorus by the so-called phosphatonin system, the lynchpin of which is fibroblast growth factor 23 (FGF23). FGF23 binds to the klotho/FGFR1c receptor complex in renal tubular epithelial cells, leading to upregulation of Na/Pi cotransporters and subsequent excretion of phosphorus from the body. In addition, FGF23 inhibits parathyroid hormone and the renal 1α-hydroxylase enzyme, while it stimulates 24-hydroxylase, leading to decreased 1,25-dihydroxyvitamin D3. FGF23 is intimately involved in the pathogenesis of a number of diseases, particularly the hereditary hypophosphatemic rickets group and chronic kidney disease, and is a target for the development of new treatments in human medicine. Little work has been done on FGF23 or the other phosphatonins in veterinary medicine, but increases in FGF23 are seen with chronic kidney disease in cats, and increased FGF23 expression has been found in soft tissue sarcomas in dogs.
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Affiliation(s)
- M. R. Hardcastle
- Gribbles Veterinary Pathology Ltd, Mt Wellington, Auckland, New Zealand
| | - K. E. Dittmer
- Animal and Biomedical Sciences, Institute of Veterinary, Massey University, Palmerston North, New Zealand
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Differential expression and regulation of Klotho by paricalcitol in the kidney, parathyroid, and aorta of uremic rats. Kidney Int 2015; 87:1141-52. [PMID: 25692955 PMCID: PMC4449811 DOI: 10.1038/ki.2015.22] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2014] [Revised: 11/21/2014] [Accepted: 12/11/2014] [Indexed: 12/29/2022]
Abstract
Klotho plays an important role in the pathogenesis of cardiovascular disease in chronic kidney disease (CKD). Klotho is highly expressed in the kidney and parathyroid glands, but its presence in the vasculature is debated. Renal Klotho is decreased in CKD, but the effect of uremia on Klotho in other tissues is not defined. The effect of vitamin D receptor activator therapy in CKD on expression of Klotho in various tissues is also in debate. In uremic rats (surgical 5/6th nephrectomy model), we compared 3-months of treatment with and without paricalcitol on Klotho immunostaining in the kidney, parathyroid glands and aorta. With uremia, Klotho was unchanged in the parathyroid, significantly decreased in the kidney (66%) and the intimal-medial area of the aorta (69%), and significantly increased in the adventitial area of the aorta (67%) compared with controls. Paricalcitol prevented the decrease in Klotho in the kidney, increased expression in the parathyroid (31%), had no effect in the aortic media, but blunted the increase of Klotho in aortic adventitia. We propose that fibroblasts are responsible for expression of Klotho in the adventitia. In hyperplastic human parathyroid tissue from uremic patients, Klotho was higher in oxyphil compared with chief cells. Thus, under our conditions of moderate CKD and mild-to-moderate hyperphosphatemia in rats, the differential expression of Klotho and its regulation by paricalcitol in uremia is tissue-dependent.
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Kooman JP, Kotanko P, Schols AMWJ, Shiels PG, Stenvinkel P. Chronic kidney disease and premature ageing. Nat Rev Nephrol 2014; 10:732-42. [PMID: 25287433 DOI: 10.1038/nrneph.2014.185] [Citation(s) in RCA: 270] [Impact Index Per Article: 27.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Chronic kidney disease (CKD) shares many phenotypic similarities with other chronic diseases, including heart failure, chronic obstructive pulmonary disease, HIV infection and rheumatoid arthritis. The most apparent similarity is premature ageing, involving accelerated vascular disease and muscle wasting. We propose that in addition to a sedentary lifestyle and psychosocial and socioeconomic determinants, four major disease-induced mechanisms underlie premature ageing in CKD: an increase in allostatic load, activation of the 'stress resistance response', activation of age-promoting mechanisms and impairment of anti-ageing pathways. The most effective current interventions to modulate premature ageing-treatment of the underlying disease, optimal nutrition, correction of the internal environment and exercise training-reduce systemic inflammation and oxidative stress and induce muscle anabolism. Deeper mechanistic insight into the phenomena of premature ageing as well as early diagnosis of CKD might improve the application and efficacy of these interventions and provide novel leads to combat muscle wasting and vascular impairment in chronic diseases.
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Affiliation(s)
- Jeroen P Kooman
- Department of Internal Medicine, Division of Nephrology, Maastricht University Medical Center, PO Box 5800, 6202 AZ Maastrich, Netherlands
| | - Peter Kotanko
- Renal Research Institute, 315 East 62nd Street, 4th floor, NY 10065, New York, USA
| | - Annemie M W J Schols
- Department of Respiratory Medicine, NUTRIM School for Nutrition, Toxicology and Metabolism, Maastricht University Medical Center, PO Box 5800, 6202 AZ Maastrich, Netherlands
| | - Paul G Shiels
- Institute of Cancer Sciences, Wolfson Wohl Translational Research Centre, University of Glasgow, Garscube Estate, Switchback Road, Bearsden, Glasgow G61 1QH, UK
| | - Peter Stenvinkel
- Division of Renal Medicine, Department of Clinical Science, Intervention and Technology, Karolinska University Hospital, Huddinge, Karolinska Institutet, SE-14157 Stockholm, Sweden
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49
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Lindberg K, Amin R, Moe OW, Hu MC, Erben RG, Östman Wernerson A, Lanske B, Olauson H, Larsson TE. The kidney is the principal organ mediating klotho effects. J Am Soc Nephrol 2014; 25:2169-75. [PMID: 24854271 PMCID: PMC4178446 DOI: 10.1681/asn.2013111209] [Citation(s) in RCA: 214] [Impact Index Per Article: 21.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2013] [Accepted: 02/26/2014] [Indexed: 12/14/2022] Open
Abstract
Klotho was discovered as an antiaging gene, and α-Klotho (Klotho) is expressed in multiple tissues with a broad set of biologic functions. Membrane-bound Klotho binds fibroblast growth factor 23 (FGF23), but a soluble form of Klotho is also produced by alternative splicing or cleavage of the extracellular domain of the membrane-bound protein. The relative organ-specific contributions to the levels and effects of circulating Klotho remain unknown. We explored these issues by generating a novel mouse strain with Klotho deleted throughout the nephron (Six2-KL(-/-)). Klotho shedding from Six2-KL(-/-) kidney explants was undetectable and the serum Klotho level was reduced by approximately 80% in Six2-KL(-/-) mice compared with wild-type littermates. Six2-KL(-/-) mice exhibited severe growth retardation, kyphosis, and premature death, closely resembling the phenotype of systemic Klotho knockout mice. Notable biochemical changes included hyperphosphatemia, hypercalcemia, hyperaldosteronism, and elevated levels of 1,25-dihydroxyvitamin D and Fgf23, consistent with disrupted renal Fgf23 signaling. Kidney histology demonstrated interstitial fibrosis and nephrocalcinosis in addition to absent dimorphic tubules. A direct comparative analysis between Six2-KL(-/-) and systemic Klotho knockout mice supports extensive, yet indistinguishable, extrarenal organ manifestations. Thus, our data reveal the kidney as the principal contributor of circulating Klotho and Klotho-induced antiaging traits.
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Affiliation(s)
- Karolina Lindberg
- Division of Renal Medicine, Department of Clinical Science, Intervention, and Technology, Karolinska Institutet, Stockholm Sweden
| | - Risul Amin
- Division of Renal Medicine, Department of Clinical Science, Intervention, and Technology, Karolinska Institutet, Stockholm Sweden
| | - Orson W Moe
- Charles and Jane Pak Center for Mineral Metabolism and Clinical Research, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, Texas
| | - Ming-Chang Hu
- Charles and Jane Pak Center for Mineral Metabolism and Clinical Research, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, Texas
| | - Reinhold G Erben
- Department of Biomedical Sciences, University of Veterinary Medicine Vienna, Vienna, Austria
| | - Annika Östman Wernerson
- Division of Pathology, Department of Laboratory Medicine, Karolinska Institutet and Karolinska University Hospital, Stockholm, Sweden
| | - Beate Lanske
- Department of Oral Medicine, Infection, and Immunity, Harvard School of Dental Medicine, Boston, Massachusetts; and
| | - Hannes Olauson
- Division of Renal Medicine, Department of Clinical Science, Intervention, and Technology, Karolinska Institutet, Stockholm Sweden
| | - Tobias E Larsson
- Division of Renal Medicine, Department of Clinical Science, Intervention, and Technology, Karolinska Institutet, Stockholm Sweden; Department of Nephrology, Karolinska University Hospital, Stockholm, Sweden
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50
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Abstract
Vitamin D is a hormone with pleiotropic effects. It mainly regulates calcium and phosphate metabolism through interactions with FGF23 and its receptor klotho. In addition, it has been shown that Vitamin D also regulates the immune response and has protective effects from cardiovascular disease, cancer and infections. Most renal transplant recipients have overt Vitamin D deficiency, a condition that may be associated with a decline in graft function and other complications. After kidney transplantation, elevated levels of FGF23 may predict increased risks of death and allograft loss. Theoretically, an optimal Vitamin D supplementation might favor operational tolerance and protect transplant recipients from the triad cardiovascular disease-cancer-infection. However, more solid data are needed to confirm this and to set the optimal level of serum Vitamin D supplementation in order to attain the best clinical outcome.
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Affiliation(s)
- Claudio Ponticelli
- Nephrology and Dialysis Unit, Humanitas Clinical and Research Centre, via Manzoni 56, Rozzano (Mi), Italy
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