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Neyra JA, Moe OW. Bone Dysregulation in Acute Kidney Injury. Nephron Clin Pract 2023; 147:747-753. [PMID: 37757785 DOI: 10.1159/000534228] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2023] [Accepted: 09/05/2023] [Indexed: 09/29/2023] Open
Abstract
Acute kidney injury (AKI) is a highly prevalent condition with multiple acute and chronic consequences. Survivors of AKI are at risk of AKI-to-chronic kidney disease (CKD) transition, which carries significant morbidity and mortality. One retrospective analysis showed increased risk of bone fracture post-AKI in humans, which was independent of CKD development. While there are several theoretical reasons for late disturbances of bone health post-AKI, no definitive data are available to date. An important question is whether there are bone sequelae from AKI that are independent of CKD, meaning bone disease prior to the onset, or in the absence of CKD - a form of "post-AKI osteopathy." While preclinical studies examining bone health after acute stressors have focused mostly on sepsis models, multiple experimental AKI models are readily available for longitudinal bone health interrogation. Future research should be tailored to define whether AKI is a risk factor, independent of CKD, for bone disease and if present, the time course and type of bone disease. This review summarizes a fraction of the existing data to provide some guidance in future research efforts.
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Affiliation(s)
- Javier A Neyra
- Department of Medicine, University of Alabama, Birmingham, Alabama, USA
- Charles and Jane Pak Center for Mineral Metabolism and Clinical Research, University of Texas Southwestern Medical Center, Dallas, Texas, USA
| | - Orson W Moe
- Charles and Jane Pak Center for Mineral Metabolism and Clinical Research, University of Texas Southwestern Medical Center, Dallas, Texas, USA
- Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, Texas, USA
- Departments of Internal Medicine and Physiology, University of Texas Southwestern Medical Center, Dallas, Texas, USA
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McCoy IE, Hsu JY, Zhang X, Diamantidis CJ, Taliercio J, Go AS, Liu KD, Drawz P, Srivastava A, Horwitz EJ, He J, Chen J, Lash JP, Weir MR, Hsu CY. Probing the Association between Acute Kidney Injury and Cardiovascular Outcomes. Clin J Am Soc Nephrol 2023; 18:01277230-990000000-00137. [PMID: 37116457 PMCID: PMC10356151 DOI: 10.2215/cjn.0000000000000163] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2023] [Accepted: 04/17/2023] [Indexed: 04/30/2023]
Abstract
BACKGROUND Patients hospitalized with AKI have higher subsequent risks of heart failure, atherosclerotic cardiovascular events, and mortality than their counterparts without AKI, but these higher risks may be due to differences in prehospitalization patient characteristics, including the baseline level of estimated glomerular filtration rate (eGFR), the rate of prior eGFR decline, and the proteinuria level, rather than AKI itself. METHODS Among 2177 adult participants in the Chronic Renal Insufficiency Cohort study who were hospitalized in 2013-2019, we compared subsequent risks of heart failure, atherosclerotic cardiovascular events, and mortality between those with serum creatinine-based AKI (495 patients) and those without AKI (1682 patients). We report both crude associations and associations sequentially adjusted for prehospitalization characteristics including eGFR, eGFR slope, and urine protein-creatinine ratio (UPCR). RESULTS Compared with patients hospitalized without AKI, those with hospitalized AKI had lower eGFR prehospitalization (42 versus 49 ml/min per 1.73 m 2 ), faster chronic loss of eGFR prehospitalization (-0.84 versus -0.51 ml/min per 1.73 m 2 per year), and more proteinuria prehospitalization (UPCR 0.28 versus 0.16 g/g); they also had higher prehospitalization systolic BP (130 versus 127 mm Hg; P < 0.01 for all comparisons). Adjustment for prehospitalization patient characteristics attenuated associations between AKI and all three outcomes, but AKI remained an independent risk factor. Attenuation of risk was similar after adjustment for absolute eGFR, eGFR slope, or proteinuria, individually or in combination. CONCLUSIONS Prehospitalization variables including eGFR, eGFR slope, and proteinuria confounded associations between AKI and adverse cardiovascular outcomes, but these associations remained significant after adjusting for prehospitalization variables.
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Affiliation(s)
- Ian E. McCoy
- Division of Nephrology, University of California San Francisco, San Francisco, California
| | - Jesse Y. Hsu
- Department of Biostatistics, Epidemiology, and Informatics, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Xiaoming Zhang
- Department of Biostatistics, Epidemiology, and Informatics, University of Pennsylvania, Philadelphia, Pennsylvania
| | | | - Jonathan Taliercio
- Department of Kidney Medicine, Cleveland Clinic Foundation, Cleveland, Ohio
| | - Alan S. Go
- Division of Research, Kaiser Permanente Northern California, Oakland, California
| | - Kathleen D. Liu
- Division of Nephrology, University of California San Francisco, San Francisco, California
| | - Paul Drawz
- Division of Nephrology and Hypertension, University of Minnesota, Minneapolis, Minnesota
| | - Anand Srivastava
- Division of Nephrology, Department of Medicine, University of Illinois Chicago, Chicago, Illinois
| | - Edward J. Horwitz
- Division of Nephrology, MetroHealth Medical Center, Case Western Reserve University, Cleveland, Ohio
| | - Jiang He
- Department of Epidemiology, Tulane University, New Orleans, Louisiana
| | - Jing Chen
- Department of Epidemiology, Tulane University, New Orleans, Louisiana
- Division of Nephrology, Tulane University, New Orleans, Louisiana
| | - James P. Lash
- Department of Medicine, University of Illinois College of Medicine at Chicago, Chicago, Illinois
| | - Matthew R. Weir
- Division of Nephrology, University of Maryland School of Medicine, Baltimore, Maryland
| | - Chi-yuan Hsu
- Division of Nephrology, University of California San Francisco, San Francisco, California
- Division of Research, Kaiser Permanente Northern California, Oakland, California
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3
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Copur S, Demiray A, Basile C, Kanbay M. Endocrinological disorders in acute kidney injury: an often overlooked field of clinical research. J Nephrol 2023; 36:885-893. [PMID: 36652168 DOI: 10.1007/s40620-022-01554-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2022] [Accepted: 12/05/2022] [Indexed: 01/19/2023]
Abstract
Acute kidney injury (AKI) is a common comorbidity, affecting approximately one in five hospitalized adults. The kidney is the site for the production, metabolism or excretion of most hormones, including the production of erythropoietin (EPO), the active form of vitamin D, renin, thrombopoietin, and the excretion of insulin, catecholamines, gastrin and many other hormones. Therefore, it is reasonable to say that AKI can have a considerable impact on the endocrine system. Although the effects of AKI on various parameters, including cardiovascular parameters, serum electrolytes and acid-base disorders, neuro-humoral mechanisms and neurological outcomes have been extensively studied, the endocrinological consequences of AKI are understudied. Thyroid dysfunction, mainly euthyroid sick syndrome, hypo/hyperglycemia, bone mineral disorders, changes in EPO and atrial natriuretic peptide (ANP) levels are commonly found in AKI. EPO, thyroxine and ANP administration have been evaluated as potential tools to prevent or treat AKI with varying success, while the effects of AKI on some key hormones, including cortisol and insulin, have never been studied. Aim of this narrative review is to illustrate what is known and what is not known about the endocrinological outcomes of AKI. Few clinical trials are ongoing: however, there is a clear need for large-scale randomized controlled trials investigating the endocrinological consequences of AKI.
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Affiliation(s)
- Sidar Copur
- Department of Medicine, Koc University School of Medicine, Istanbul, Turkey
| | - Atalay Demiray
- Department of Medicine, Koc University School of Medicine, Istanbul, Turkey
| | - Carlo Basile
- Associazione Nefrologica Gabriella Sebastio, Martina Franca, Italy.
| | - Mehmet Kanbay
- Department of Medicine, Division of Nephrology, Koc University School of Medicine, Istanbul, Turkey
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Jones GRD, Chung JZY. The effect of acute changes in glomerular filtration rate on common biochemical tests. Pract Lab Med 2022; 31:e00280. [PMID: 35669080 PMCID: PMC9163749 DOI: 10.1016/j.plabm.2022.e00280] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2022] [Revised: 05/12/2022] [Accepted: 05/13/2022] [Indexed: 01/05/2023] Open
Abstract
Objectives To characterise the effect of acute kidney injury on the concentration of common biochemical analytes. Design and methods: Pairs of serum or plasma samples from the same patients routinely submitted to the laboratory were subject to further analysis based on changes in serum creatinine within 72 h. Samples collected from patients on dialysis were excluded. Samples were measured for 28 biochemical analytes including electrolytes, liver function tests, iron studies, creatine kinase, amylase, lipase, parathyroid hormone, troponin T and troponin I, B-natriuretic peptide and NT pro B-natriuretic peptide. Results 148 sample pairs were included with 99 having a rise in serum creatinine >50%, 18 with a fall of >50% and 31 with smaller changes. Acute changes in renal function were associated with changes in the concentration of several analytes, with the changes of the greatest magnitude observed in urea, phosphate, urate, parathyroid hormone, troponin T, BNP and NT-ProBNP. The remaining analytes did not show significant changes with changes in renal function. Conclusion Acute changes in renal function are associated with significant changes in concentration of some serum/plasma biochemical analytes but not others. Expected changes in analyte concentration must be considered in the setting of acute kidney injury to avoid misinterpretation of blood test results.
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Affiliation(s)
- Graham Ross Dallas Jones
- Department of Chemical Pathology, SydPath, St Vincent's Hospital, Sydney, Victoria St, Darlinghurst, NSW, 2010, Australia
- Faculty of Medicine, University of New South Wales, Randwick, NSW, 2031, Australia
| | - Jason Zhi Yong Chung
- Department of Biochemistry, The Children's Hospital at Westmead, Westmead, NSW, 2145, Australia
- The Children's Hospital at Westmead Clinical School, The University of Sydney, Westmead, NSW, 2145, Australia
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The Role of Vitamin D in SARS-CoV-2 Infection and Acute Kidney Injury. Int J Mol Sci 2022; 23:ijms23137368. [PMID: 35806377 PMCID: PMC9266309 DOI: 10.3390/ijms23137368] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2022] [Revised: 06/30/2022] [Accepted: 06/30/2022] [Indexed: 02/04/2023] Open
Abstract
Vitamin D has been described as an essential nutrient and hormone, which can cause nuclear, non-genomic, and mitochondrial effects. Vitamin D not only controls the transcription of thousands of genes, directly or indirectly through the modulation of calcium fluxes, but it also influences the cell metabolism and maintenance specific nuclear programs. Given its broad spectrum of activity and multiple molecular targets, a deficiency of vitamin D can be involved in many pathologies. Vitamin D deficiency also influences mortality and multiple outcomes in chronic kidney disease (CKD). Active and native vitamin D serum levels are also decreased in critically ill patients and are associated with acute kidney injury (AKI) and in-hospital mortality. In addition to regulating calcium and phosphate homeostasis, vitamin D-related mechanisms regulate adaptive and innate immunity. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections have a role in excessive proinflammatory cell recruitment and cytokine release, which contribute to alveolar and full-body endothelial damage. AKI is one of the most common extrapulmonary manifestations of severe coronavirus disease 2019 (COVID-19). There are also some correlations between the vitamin D level and COVID-19 severity via several pathways. Proper vitamin D supplementation may be an attractive therapeutic strategy for AKI and has the benefits of low cost and low risk of toxicity and side effects.
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Singh NP, Panwar V, Aggarwal NP, Chhabra SK, Gupta AK, Ganguli A. Regulation of Calcium Homeostasis in Acute Kidney Injury: A Prospective Observational Study. Indian J Crit Care Med 2022; 26:302-306. [PMID: 35519919 PMCID: PMC9015928 DOI: 10.5005/jp-journals-10071-24124] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
Background Maintaining homeostasis is an integral part of all physiological processes both in health and disease including critically ill patients and may impact clinical outcomes. The present study was designed to assess prevalence of serum calcium, phosphate, vitamin-D3, FGF-23, and PTH levels abnormalities in AKI. Patients and methods Single-center, prospective, observational study in a tertiary care hospital. Patients meeting KDIGO criteria for AKI were included. Paired blood samples were drawn from eligible patients—first sample within 24 hours of AKI diagnosis and second after 5 days or at time of hospital discharge, whichever was earlier for measuring serum calcium (albumin corrected), phosphate, PTH, 25(OH)Vit-D, and FGF-23 levels. Clinical outcomes analyzed included survival status, utilization of RRT, and hospital stay. Results Of the 50 patients with AKI, about three-fourths were males. Mean age of the participants was 57.32 ± 11.47 years. Around half of patients had hypocalcemia and four-fifths had low serum phosphate. Nearly 82% had low 25(OH)Vit-D and 52% cases had high PTH level. Patients who underwent RRT had numerically higher but not significant serum calcium and PTH levels. FGF-23 levels (pg/mL) were significantly higher in patients on RRT (81.70 ± 17.30 vs non-RRT, 72.43 ± 20.27, p = 0.049), nonsurvivors (87.96 ± 18.82 vs survivors 57.11 ± 15.19, p = 0.045), and those hospitalized for time of stay above median (109.67 ± 26.97 vs below median 70.27 ± 20.43, p = 0.046). Among all the bone and mineral parameters analyzed high FGF23 levels were consistently linked with poor clinical outcomes in AKI. Conclusion The present study found high prevalence of calcium and phosphate disorders in AKI with dysregulated phosphate homeostasis as evidenced from elevated FGF-23 levels linked with morbidity and mortality in AKI. How to cite this article Singh NP, Panwar V, Aggarwal NP, Chhabra SK, Gupta AK, Ganguli A. Regulation of Calcium Homeostasis in Acute Kidney Injury: A Prospective Observational Study. Indian J Crit Care Med 2022;26(3):302–306.
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Affiliation(s)
- Narinder Pal Singh
- Faculty of Medicine and Health Sciences, SGT Medical College Hospital and Research Institute, Gurugram, Haryana, India
- Narinder Pal Singh, Faculty of Medicine and Health Sciences, SGT Medical College Hospital and Research Institute, Gurugram, Haryana, India, Phone: +91 9868446621, e-mail:
| | - Vikrant Panwar
- Department of Gastroenterology, Artemis Institute of Health Sciences, Gurugram, Haryana, India
| | - Neeru P Aggarwal
- Department of Nephrology, Max Super Speciality Hospital, Ghaziabad, Uttar Pradesh, India
| | - Satish K Chhabra
- Department of Nephrology, Max Super Speciality Hospital, Patparganj, New Delhi, India
| | - Anish K Gupta
- Faculty of Medicine and Health Sciences, SGT Medical College Hospital and Research Institute, Gurugram, Haryana, India
| | - Anirban Ganguli
- Department of Nephrology, Georgetown University, Washington, DC, United States of America
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Molecular Mechanisms and Biomarkers Associated with Chemotherapy-Induced AKI. Int J Mol Sci 2022; 23:ijms23052638. [PMID: 35269781 PMCID: PMC8910619 DOI: 10.3390/ijms23052638] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2022] [Revised: 02/25/2022] [Accepted: 02/25/2022] [Indexed: 12/10/2022] Open
Abstract
Acute kidney injury (AKI) is a life-threatening condition characterized by a rapid and transient decrease in kidney function. AKI is part of an array of conditions collectively defined as acute kidney diseases (AKD). In AKD, persistent kidney damage and dysfunction lead to chronic kidney disease (CKD) over time. A variety of insults can trigger AKI; however, chemotherapy-associated nephrotoxicity is increasingly recognized as a significant side effect of chemotherapy. New biomarkers are urgently needed to identify patients at high risk of developing chemotherapy-associated nephrotoxicity and subsequent AKI. However, a lack of understanding of cellular mechanisms that trigger chemotherapy-related nephrotoxicity has hindered the identification of effective biomarkers to date. In this review, we aim to (1) describe the known and potential mechanisms related to chemotherapy-induced AKI; (2) summarize the available biomarkers for early AKI detection, and (3) raise awareness of chemotherapy-induced AKI.
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Zechner C, Adams-Huet B, Gregory B, Neyra JA, Rule JA, Li X, Rakela J, Moe OW, Lee WM. Hypophosphatemia in acute liver failure of a broad range of etiologies is associated with phosphaturia without kidney damage or phosphatonin elevation. Transl Res 2021; 238:1-11. [PMID: 34298149 PMCID: PMC8572166 DOI: 10.1016/j.trsl.2021.07.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/16/2021] [Revised: 06/21/2021] [Accepted: 07/15/2021] [Indexed: 11/19/2022]
Abstract
Hypophosphatemia is a common and dangerous complication of acute liver failure (ALF) of various etiologies. While various mechanisms for ALF-associated hypophosphatemia have been proposed including high phosphate uptake into regenerating hepatocytes, acetaminophen (APAP)-associated hypophosphatemia was linked to renal phosphate wasting, and APAP-induced renal tubular injury was proposed as underlying mechanism. We studied 30 normophosphatemic and 46 hypophosphatemic (serum phosphate < 2.5 mg/dL) patients from the Acute Liver Failure Study Group registry with APAP- or non-APAP-induced ALF. Since kidney injury affects phosphate excretion, patients with elevated serum creatinine (>1.2 mg/dL) were excluded. Maximal amount of renal tubular phosphate reabsorption per filtered volume (TmP/GFR) was calculated from simultaneous serum and urine phosphate and creatinine levels to assess renal phosphate handling. Instead of enhanced renal phosphate reabsorption as would be expected during hypophosphatemia of non-renal causes, serum phosphate was positively correlated with TmP/GFR in both APAP- and non-APAP-induced ALF patients (R2 = 0.66 and 0.46, respectively; both P < 0.0001), indicating renal phosphate wasting. Surprisingly, there was no evidence of kidney damage based on urinary markers including neutrophil gelatinase-associated lipocalin and cystatin C even in the APAP group. Additionally, there was no evidence that the known serum phosphatonins parathyroid hormone, fibroblast growth factor 23, and α-Klotho contribute to the observed hypophosphatemia. We conclude that the observed hypophosphatemia with renal phosphate wasting in both APAP- and non-APAP-mediated ALF is likely the result of renal tubular phosphate leak from yet-to-be identified factor(s) with no evidence for proximal tubular damage or contribution of known phosphatonins.
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Affiliation(s)
- Christoph Zechner
- Division of Endocrinology, Department of Internal Medicine, UT Southwestern Medical Center, Dallas, Texas, USA; Department of Pharmacology. UT Southwestern Medical Center, Dallas, Texas, USA; Charles and Jane Pak Center for Mineral Metabolism and Clinical Research, UT Southwestern Medical Center, Dallas, Texas, USA.
| | - Beverley Adams-Huet
- Charles and Jane Pak Center for Mineral Metabolism and Clinical Research, UT Southwestern Medical Center, Dallas, Texas, USA; Division of Biostatistics, Population and Data Sciences, Department of Clinical Sciences, UT Southwestern Medical Center, Dallas, Texas, USA
| | - Blake Gregory
- Division of Digestive and Liver Diseases, Department of Internal Medicine, UT Southwestern Medical Center, Dallas, Texas, USA; Division of Primary Care, Department of Internal Medicine, Alameda Health System, Oakland, California, USA
| | - Javier A Neyra
- Charles and Jane Pak Center for Mineral Metabolism and Clinical Research, UT Southwestern Medical Center, Dallas, Texas, USA; Division of Nephrology, Department of Internal Medicine, UT Southwestern Medical Center, Dallas, Texas, USA; Division of Nephrology, Bone and Mineral Metabolism, Department of Internal Medicine, University of Kentucky, Lexington, Kentucky, USA
| | - Jody A Rule
- Division of Digestive and Liver Diseases, Department of Internal Medicine, UT Southwestern Medical Center, Dallas, Texas, USA
| | - Xilong Li
- Division of Biostatistics, Population and Data Sciences, Department of Clinical Sciences, UT Southwestern Medical Center, Dallas, Texas, USA
| | - Jorge Rakela
- Division of Gastroenterology and Hepatology, Mayo Clinic Arizona, Phoenix, Arizona, USA
| | - Orson W Moe
- Charles and Jane Pak Center for Mineral Metabolism and Clinical Research, UT Southwestern Medical Center, Dallas, Texas, USA; Division of Nephrology, Department of Internal Medicine, UT Southwestern Medical Center, Dallas, Texas, USA; Department of Physiology, UT Southwestern Medical Center, Dallas, Texas, USA
| | - William M Lee
- Division of Digestive and Liver Diseases, Department of Internal Medicine, UT Southwestern Medical Center, Dallas, Texas, USA.
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FGF23 ameliorates ischemia-reperfusion induced acute kidney injury via modulation of endothelial progenitor cells: targeting SDF-1/CXCR4 signaling. Cell Death Dis 2021; 12:409. [PMID: 33866326 PMCID: PMC8053200 DOI: 10.1038/s41419-021-03693-w] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/25/2020] [Revised: 03/30/2021] [Accepted: 04/01/2021] [Indexed: 01/09/2023]
Abstract
The levels of fibroblast growth factor 23 (FGF23) rapidly increases after acute kidney injury (AKI). However, the role of FGF23 in AKI is still unclear. Here, we observe that pretreatment with FGF23 protein into ischemia-reperfusion induced AKI mice ameliorates kidney injury by promoting renal tubular regeneration, proliferation, vascular repair, and attenuating tubular damage. In vitro assays demonstrate that SDF-1 induces upregulation of its receptor CXCR4 in endothelial progenitor cells (EPCs) via a non-canonical NF-κB signaling pathway. FGF23 crosstalks with the SDF-1/CXCR4 signaling and abrogates SDF-1-induced EPC senescence and migration, but not angiogenesis, in a Klotho-independent manner. The downregulated pro-angiogenic IL-6, IL-8, and VEGF-A expressions after SDF-1 infusion are rescued after adding FGF23. Diminished therapeutic ability of SDF-1-treated EPCs is counteracted by FGF23 in a SCID mouse in vivo AKI model. Together, these data highlight a revolutionary and important role that FGF23 plays in the nephroprotection of IR-AKI.
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10
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Bonavia A, Stiles N. Renohepatic crosstalk: a review of the effects of acute kidney injury on the liver. Nephrol Dial Transplant 2021; 37:1218-1228. [PMID: 33527986 DOI: 10.1093/ndt/gfaa297] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2020] [Indexed: 12/13/2022] Open
Abstract
Several theories regarding acute kidney injury (AKI)-related mortality have been entertained, although mounting evidence supports the paradigm that impaired kidney function directly and adversely affects the function of several remote organs. The kidneys and liver are fundamental to human metabolism and detoxification, and it is therefore hardly surprising that critical illness complicated by hepatorenal dysfunction portends a poor prognosis. Several diseases can simultaneously impact the proper functioning of the liver and kidneys, although this review will address the impact of AKI on liver function. While evidence for this relationship in humans remains sparse, we present supportive studies and then discuss the most likely mechanisms by which AKI can cause liver dysfunction. These include 'traditional' complications of AKI (uremia, volume overload and acute metabolic acidosis, among others) as well as systemic inflammation, hepatic leukocyte infiltration, cytokine-mediated liver injury and hepatic oxidative stress. We conclude by addressing the therapeutic implications of these findings to clinical medicine.
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Affiliation(s)
- Anthony Bonavia
- Department of Anesthesiology and Perioperative Medicine, Penn State Milton S. Hershey Medical Center, Hershey, PA, USA.,Department of Pharmacology, Penn State College of Medicine, Hershey, PA, USA
| | - Nicholas Stiles
- Department of Anesthesiology and Perioperative Medicine, Penn State Milton S. Hershey Medical Center, Hershey, PA, USA
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Kangelaris KN, Clemens R, Fang X, Jauregui A, Liu T, Vessel K, Deiss T, Sinha P, Leligdowicz A, Liu KD, Zhuo H, Alder MN, Wong HR, Calfee CS, Lowell C, Matthay MA. A neutrophil subset defined by intracellular olfactomedin 4 is associated with mortality in sepsis. Am J Physiol Lung Cell Mol Physiol 2020; 320:L892-L902. [PMID: 33355521 DOI: 10.1152/ajplung.00090.2020] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Sepsis is a heterogeneous syndrome clinically and biologically, but biomarkers of distinct host response pathways for early prognostic information and testing targeted treatments are lacking. Olfactomedin 4 (OLFM4), a matrix glycoprotein of neutrophil-specific granules, defines a distinct neutrophil subset that may be an independent risk factor for poor outcomes in sepsis. We hypothesized that increased percentage of OLFM4+ neutrophils on sepsis presentation would be associated with mortality. In a single-center, prospective cohort study, we enrolled adults admitted to an academic medical center from the emergency department (ED) with suspected sepsis [identified by 2 or greater systemic inflammatory response syndrome (SIRS) criteria and antibiotic receipt] from March 2016 through December 2017, followed by sepsis adjudication according to Sepsis-3. We collected 200 µL of whole blood within 24 h of admission and stained for the neutrophil surface marker CD66b followed by intracellular staining for OLFM4 quantitated by flow cytometry. The predictors for 60-day mortality were 1) percentage of OLFM4+ neutrophils and 2) OLFM4+ neutrophils at a cut point of ≥37.6% determined by the Youden Index. Of 120 enrolled patients with suspected sepsis, 97 had sepsis and 23 had nonsepsis SIRS. The mean percentage of OLFM4+ neutrophils was significantly increased in both sepsis and nonsepsis SIRS patients who died (P ≤ 0.01). Among sepsis patients with elevated OLFM4+ (≥37.6%), 56% died, compared with 18% with OLFM4+ <37.6% (P = 0.001). The association between OLFM4+ and mortality withstood adjustment for age, sex, absolute neutrophil count, comorbidities, and standard measures of severity of illness (SOFA score, APACHE III) (P < 0.03). In summary, OLFM4+ neutrophil percentage is independently associated with 60-day mortality in sepsis and may represent a novel measure of the heterogeneity of host response to sepsis.
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Affiliation(s)
- Kirsten N Kangelaris
- Division of Hospital Medicine, Department of Medicine, University of California, San Francisco, California
| | - Regina Clemens
- Division of Hospital Medicine, Department of Medicine, University of California, San Francisco, California
| | - Xiaohui Fang
- Department of Medicine, Cardiovascular Research Institute, University of California, San Francisco, California.,Department of Anesthesia, Cardiovascular Research Institute, University of California, San Francisco, California
| | - Alejandra Jauregui
- Department of Medicine, Cardiovascular Research Institute, University of California, San Francisco, California.,Department of Anesthesia, Cardiovascular Research Institute, University of California, San Francisco, California
| | - Tom Liu
- Department of Medicine, Cardiovascular Research Institute, University of California, San Francisco, California.,Department of Anesthesia, Cardiovascular Research Institute, University of California, San Francisco, California
| | - Kathryn Vessel
- Department of Medicine, Cardiovascular Research Institute, University of California, San Francisco, California.,Department of Anesthesia, Cardiovascular Research Institute, University of California, San Francisco, California
| | - Thomas Deiss
- Department of Medicine, Cardiovascular Research Institute, University of California, San Francisco, California.,Department of Anesthesia, Cardiovascular Research Institute, University of California, San Francisco, California
| | - Pratik Sinha
- Department of Medicine, Cardiovascular Research Institute, University of California, San Francisco, California.,Department of Anesthesia, Cardiovascular Research Institute, University of California, San Francisco, California
| | - Aleksandra Leligdowicz
- Department of Medicine, Cardiovascular Research Institute, University of California, San Francisco, California.,Department of Anesthesia, Cardiovascular Research Institute, University of California, San Francisco, California.,Interdepartmental Division of Critical Care Medicine, University of Toronto, Toronto, Ontario, Canada
| | - Kathleen D Liu
- Department of Medicine, Cardiovascular Research Institute, University of California, San Francisco, California.,Department of Anesthesia, Cardiovascular Research Institute, University of California, San Francisco, California
| | - Hanjing Zhuo
- Department of Medicine, Cardiovascular Research Institute, University of California, San Francisco, California.,Department of Anesthesia, Cardiovascular Research Institute, University of California, San Francisco, California
| | - Matthew N Alder
- Division of Critical Care Medicine, Department of Pediatrics, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio
| | - Hector R Wong
- Division of Critical Care Medicine, Department of Pediatrics, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio
| | - Carolyn S Calfee
- Department of Medicine, Cardiovascular Research Institute, University of California, San Francisco, California.,Department of Anesthesia, Cardiovascular Research Institute, University of California, San Francisco, California
| | - Clifford Lowell
- Department of Laboratory Medicine, University of California, San Francisco, California
| | - Michael A Matthay
- Department of Medicine, Cardiovascular Research Institute, University of California, San Francisco, California.,Department of Anesthesia, Cardiovascular Research Institute, University of California, San Francisco, California
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12
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Alternative Tobacco Product Use in Critically Ill Patients. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2020; 17:ijerph17238707. [PMID: 33255164 PMCID: PMC7727672 DOI: 10.3390/ijerph17238707] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/21/2020] [Revised: 11/20/2020] [Accepted: 11/20/2020] [Indexed: 01/15/2023]
Abstract
Background: Alternative tobacco product (ATP) use has bee linked to critical illness, however, few studies have examined the use of these substances in critically ill populations. We sought to examine ATP use within critically ill patients and to define barriers in accurately assessing use within this population. Methods: We prospectively studied 533 consecutive patients from the Early Assessment of Renal and Lung Injury study, enrolled between 2013 and 2016 at a tertiary referral center and a safety-net hospital. ATP use information (electronic cigarettes, cigars, pipes, hookahs/waterpipes, and snus/chewing tobacco) was obtained from the patient or surrogate using a detailed survey. Reasons for non-completion of the survey were recorded, and differences between survey responders vs. non-responders, self- vs. surrogate responders, and ATP users vs. non-users were explored. Results: Overall, 80% (n = 425) of subjects (56% male) completed a tobacco product use survey. Of these, 12.2% (n = 52) reported current ATP use, while 5.6% reported using multiple ATP products. When restricted to subjects who were self-responders, 17% reported ATP use, while 10% reported current cigarette smoking alone. The mean age of ATP users was 57 ± 17 years. Those who did not complete a survey were sicker and more likely to have died during admission. Subjects who completed the survey as self-responders reported higher levels of ATP use than ones with surrogate responders (p < 0.0001). Conclusion: ATP use is common among critically ill patients despite them being generally older than traditional users. Survey self-responders were more likely than surrogate responders to report use. These findings highlight the importance of improving our current methods of surveillance of ATP use in older adults in the outpatient setting.
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Mace ML, Olgaard K, Lewin E. New Aspects of the Kidney in the Regulation of Fibroblast Growth Factor 23 (FGF23) and Mineral Homeostasis. Int J Mol Sci 2020; 21:E8810. [PMID: 33233840 PMCID: PMC7699902 DOI: 10.3390/ijms21228810] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2020] [Revised: 11/16/2020] [Accepted: 11/19/2020] [Indexed: 02/07/2023] Open
Abstract
The bone-derived hormone fibroblast growth factor 23 (FGF23) acts in concert with parathyroid hormone (PTH) and the active vitamin D metabolite calcitriol in the regulation of calcium (Ca) and phosphate (P) homeostasis. More factors are being identified to regulate FGF23 levels and the endocrine loops between the three hormones. The present review summarizes the complex regulation of FGF23 and the disturbed FGF23/Klotho system in chronic kidney disease (CKD). In addition to the reduced ability of the injured kidney to regulate plasma levels of FGF23, several CKD-related factors have been shown to stimulate FGF23 production. The high circulating FGF23 levels have detrimental effects on erythropoiesis, the cardio-vascular system and the immune system, all contributing to the disturbed system biology in CKD. Moreover, new factors secreted by the injured kidney and the uremic calcified vasculature play a role in the mineral and bone disorder in CKD and create a vicious pathological crosstalk.
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Affiliation(s)
- Maria L. Mace
- Department of Nephrology, Rigshospitalet, University of Copenhagen, 2100 Copenhagen, Denmark; (K.O.); (E.L.)
| | - Klaus Olgaard
- Department of Nephrology, Rigshospitalet, University of Copenhagen, 2100 Copenhagen, Denmark; (K.O.); (E.L.)
| | - Ewa Lewin
- Department of Nephrology, Rigshospitalet, University of Copenhagen, 2100 Copenhagen, Denmark; (K.O.); (E.L.)
- Department of Nephrology, Herlev Hospital, University of Copenhagen, 2730 Herlev, Denmark
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Inflammation both increases and causes resistance to FGF23 in normal and uremic rats. Clin Sci (Lond) 2020; 134:15-32. [PMID: 31860056 DOI: 10.1042/cs20190779] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2019] [Revised: 12/03/2019] [Accepted: 12/20/2019] [Indexed: 12/19/2022]
Abstract
Fibroblast growth factor 23 (FGF23) increases phosphorus excretion and decreases calcitriol (1,25(OH)2D) levels. FGF23 increases from early stages of renal failure. We evaluated whether strict control of phosphorus intake in renal failure prevents the increase in FGF23 and to what extent inflammation impairs regulation of FGF23. The study was performed in 5/6 nephrectomized (Nx) Wistar rats fed diets containing 0.2-1.2% phosphorus for 3 or 15 days. FGF23 levels significantly increased in all Nx groups in the short-term (3-day) experiment. However, at 15 days, FGF23 increased in all Nx rats except in those fed 0.2% phosphorus. In a second experiment, Nx rats fed low phosphorus diets (0.2 and 0.4%) for 15 days received daily intraperitoneal lipopolysaccharide (LPS) injections to induce inflammation. In these rats, FGF23 increased despite the low phosphorus diets. Thus, higher FGF23 levels were needed to maintain phosphaturia and normal serum phosphorus values. Renal Klotho expression was preserved in Nx rats on a 0.2% phosphorus diet, reduced on a 0.4% phosphorus diet, and markedly reduced in Nx rats receiving LPS. In ex vivo experiments, high phosphorus and LPS increased nuclear β-catenin and p65-NFκB and decreased Klotho. Inhibition of inflammation and Wnt signaling activation resulted in decreased FGF23 levels and increased renal Klotho. In conclusion, strict control of phosphorus intake prevented the increase in FGF23 in renal failure, whereas inflammation independently increased FGF23 values. Decreased Klotho may explain the renal resistance to FGF23 in inflammation. These effects are likely mediated by the activation of NFkB and Wnt/β-catenin signaling.
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Fayed A, Radwan WA, Amin M, Gamal A. Prediction of mortality and need for renal replacement therapy in patients of acute kidney injury using fibroblast growth factor 23. SAUDI JOURNAL OF KIDNEY DISEASES AND TRANSPLANTATION 2020; 30:1044-1051. [PMID: 31696842 DOI: 10.4103/1319-2442.270259] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Abstract
Acute kidney injury (AKI) occurs in up to 50% of patients admitted to the intensive care units. Fibroblast growth factor 23 (FGF23), which plays an important role in regulating phosphate, rises early in AKI. Few studies were conducted to correlate the level of FGF23 and adverse outcomes in AKI. The study was conducted on 30 participants with AKI, which was defined according to AKI network criteria, admitted to the Critical Care Department, Kasr El Aini Hospital, Cairo University between July 2016 and May 2017, and serum FGF23 was measured within 24 h of AKI onset to correlate the level of FGF23 with mortality and need for renal replacement therapy (RRT). Enrollment FGF23 levels were significantly higher among patients who died than in the survival group (mean level: 544.2 vs. 59.3 pg/mL, P = 0.004). Furthermore, FGF23 levels were significantly higher in patients who needed RRT than in other participants (mean level: 529.5 vs. 285.11 pg/mL, P = 0.04). There was a statistically significant positive relationship between FGF23 level and sequential organ failure assessment score (P = 0.03). In patients with AKI, higher FGF23 levels are associated with increased risk of mortality and need for RRT.
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Affiliation(s)
- Ahmed Fayed
- Department of Internal Medicine, Nephrology Unit, Kasr Al Aini School of Medicine, Cairo University, Cairo, Egypt
| | - Waheed Ahmed Radwan
- Department of Critical Care, Kasr El Aini School of Medicine, Cairo University, Cairo, Egypt
| | - Mohamed Amin
- Department of Critical Care, Kasr El Aini School of Medicine, Cairo University, Cairo, Egypt
| | - Ahmed Gamal
- Department of Critical Care, Kasr El Aini School of Medicine, Cairo University, Cairo, Egypt
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Hegde A, Denburg MR, Glenn DA. Acute Kidney Injury and Pediatric Bone Health. Front Pediatr 2020; 8:635628. [PMID: 33634055 PMCID: PMC7900149 DOI: 10.3389/fped.2020.635628] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/30/2020] [Accepted: 12/30/2020] [Indexed: 12/29/2022] Open
Abstract
Acute kidney injury (AKI) has been associated with deleterious impacts on a variety of body systems. While AKI is often accompanied by dysregulation of mineral metabolism-including alterations in calcium, phosphate, vitamin D, parathyroid hormone, fibroblast growth factor 23, and klotho-its direct effects on the skeletal system of children and adolescents remain largely unexplored. In this review, the pathophysiology of dysregulated mineral metabolism in AKI and its potential effects on skeletal health are discussed, including data associating AKI with fracture risk.
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Affiliation(s)
- Anisha Hegde
- Department of Pediatrics, University of North Carolina Hospitals, Chapel Hill, NC, United States
| | - Michelle R Denburg
- Division of Nephrology, The Children's Hospital of Philadelphia, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States
| | - Dorey A Glenn
- Division of Nephrology, University of North Carolina School of Medicine, Chapel Hill, NC, United States
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Postdischarge Major Adverse Cardiovascular Events of ICU Survivors Who Received Acute Renal Replacement Therapy. Crit Care Med 2019; 46:e1047-e1054. [PMID: 30095497 DOI: 10.1097/ccm.0000000000003357] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
OBJECTIVES Long-term risk of a major adverse cardiovascular events in ICU survivors who underwent acute renal replacement therapy requires further investigation. DESIGN Nationwide population-based study using the claims database of Korea. SETTING Index admission cases of ICU survivors in government-designated tertiary hospitals PATIENTS:: The study group consisted of ICU survivors who underwent acute renal replacement therapy, and the control group consisted of those without acute renal replacement therapy. Patients were excluded if they 1) were under age 20, 2) expired within 30 days after discharge, 3) received ICU care for less than 24 hours, 4) had a previous ICU admission, 5) had a history of major adverse cardiovascular event, or 6) had a major adverse cardiovascular event-related cardio/cerebrovascular diseases. The outcomes of the patients who received continuous renal replacement therapy were compared with those of patients who received only intermittent renal replacement therapy. INTERVENTIONS None. MEASUREMENTS AND MAIN RESULTS Information regarding patient characteristics and treatment modalities was collected and adjusted. The main outcome was major adverse cardiovascular event, including acute myocardial infarction, revascularization, and acute ischemic stroke. Patient mortality and progression to end-stage renal disease were also evaluated. We included 12,380 acute renal replacement therapy patients and 382,018 patients in the control group. Among the study group, 6,891 patients were included in the continuous renal replacement therapy group, and 5,034 in the intermittent renal replacement therapy group. The risks of major adverse cardiovascular event (adjusted hazard ratio, 1.463 [1.323-1.619]; p < 0.001), all-cause mortality (adjusted hazard ratio, 1.323 [1.256-1.393]; p < 0.001), and end-stage renal disease (adjusted hazard ratio, 18.110 [15.779-20.786]; p < 0.001) were higher in the acute renal replacement therapy patients than the control group. When we compared the continuous renal replacement therapy patients with the intermittent renal replacement therapy patients, the risk of major adverse cardiovascular event was comparable (adjusted hazard ratio, 1.049 [0.888-1.239]; p = 0.575). CONCLUSIONS Clinicians should note the increased risk of a long-term major adverse cardiovascular event in acute renal replacement therapy patients and consider appropriate risk factor management. Significant difference in the risk of postdischarge major adverse cardiovascular event was not identified between continuous renal replacement therapy and intermittent renal replacement therapy.
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Abstract
The care of patients with acute kidney injury (AKI) has been limited due to the lack of effective therapeutics that can either prevent AKI during high-risk situations or treat AKI once established. A revolution in the scientific understanding of the pathogenesis of AKI has led to the identification of potential therapeutic targets. These targets include pathways involved in inflammation, cellular repair and fibrosis, cellular metabolism and mitochondrial function, oxidative stress, apoptosis, and hemodynamics and oxygen delivery. Many compounds are entering early-phase clinical trials. In addition, efforts to better describe sub-categories of AKI (through endo-phenotyping) hold promise to target therapies more effectively based upon pathways that are operative in the pathogenesis. These advances bring optimism that the care of patients with AKI will be transformed with the hope of better outcomes.
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Affiliation(s)
- Matthew Hulse
- Divison of Critical Care, Department of Anesthesiology, University of Virginia Health System, Charlottesville, VA, 22908, USA
| | - Mitchell H Rosner
- Division of Nephrology, Department of Medicine, University of Virginia Health System, 135 Hospital Drive, Suite 1031, Charlottesville, VA, 22908, USA.
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Bär L, Stournaras C, Lang F, Föller M. Regulation of fibroblast growth factor 23 (FGF23) in health and disease. FEBS Lett 2019; 593:1879-1900. [PMID: 31199502 DOI: 10.1002/1873-3468.13494] [Citation(s) in RCA: 52] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2019] [Revised: 03/26/2019] [Accepted: 03/27/2019] [Indexed: 12/19/2022]
Abstract
Fibroblast growth factor 23 (FGF23) is mainly produced in the bone and, upon secretion, forms a complex with a FGF receptor and coreceptor αKlotho. FGF23 can exert several endocrine functions, such as inhibiting renal phosphate reabsorption and 1,25-dihydroxyvitamin D3 production. Moreover, it has paracrine activities on several cell types, including neutrophils and hepatocytes. Klotho and Fgf23 deficiencies result in pathologies otherwise encountered in age-associated diseases, mainly as a result of hyperphosphataemia-dependent calcification. FGF23 levels are also perturbed in the plasma of patients with several disorders, including kidney or cardiovascular diseases. Here, we review mechanisms controlling FGF23 production and discuss how FGF23 regulation is perturbed in disease.
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Affiliation(s)
- Ludmilla Bär
- Institute of Agricultural and Nutritional Sciences, Martin Luther University Halle-Wittenberg, Halle (Saale), Germany
| | - Christos Stournaras
- Institute of Biochemistry, University of Crete Medical School, Heraklion, Greece
| | - Florian Lang
- Institute of Physiology, University of Tübingen, Germany
| | - Michael Föller
- Institute of Physiology, University of Hohenheim, Stuttgart, Germany
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20
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Abstract
Acute kidney injury (AKI) is associated with many of the same mineral metabolite abnormalities that are observed in chronic kidney disease. These include increased circulating levels of the osteocyte-derived, vitamin D-regulating hormone, fibroblast growth factor 23 (FGF23), and decreased renal expression of klotho, the co-receptor for FGF23. Recent data have indicated that increased FGF23 and decreased klotho levels in the blood and urine could serve as novel predictive biomarkers of incident AKI, or as novel prognostic biomarkers of adverse outcomes in patients with established AKI. In addition, because FGF23 and klotho exert numerous classic as well as off-target effects on a variety of organ systems, targeting their dysregulation in AKI may represent a unique opportunity for therapeutic intervention. We review the pathophysiology, kinetics, and regulation of FGF23 and klotho in animal and human studies of AKI, and we discuss the challenges and opportunities involved in targeting FGF23 and klotho therapeutically.
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Affiliation(s)
- Marta Christov
- Department of Medicine, New York Medical College, Valhalla, NY.
| | - Javier A Neyra
- Division of Nephrology, Bone and Mineral Metabolism, Department of Internal Medicine, University of Kentucky, Lexington, KY; Division of Nephrology, Department of Internal Medicine, University of Texas Southwestern, Dallas, TX
| | - Sanjeev Gupta
- Department of Medicine, New York Medical College, Valhalla, NY
| | - David E Leaf
- Division of Renal Medicine, Brigham and Women's Hospital, Boston, MA
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Renal ischemia-reperfusion injury impairs renal calcium, magnesium, and phosphate handling in mice. Pflugers Arch 2019; 471:901-914. [PMID: 30685787 DOI: 10.1007/s00424-019-02255-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2018] [Revised: 01/04/2019] [Accepted: 01/10/2019] [Indexed: 01/04/2023]
Abstract
Fibroblast growth factor 23 (FGF23) levels are elevated in patients with acute kidney injury (AKI). The consequences on renal Ca2+, Mg2+, and Pi regulatory mechanisms are unknown. We hypothesized that renal ischemia-reperfusion (I/R) injury alters the expression of important renal Ca2+, Mg2+, and Pi transport proteins. I/R injury was induced in male C57BL/6 mice by clamping both renal arteries for 27 min. Mice were investigated 18 h later. The mRNA and protein levels of renal Ca2+, Mg2+, and Pi transport proteins were measured by RT-qPCR and western blot analysis. I/R injury-induced hyperphosphatemia and hypermagnesemia were paralleled by a decrease in glomerular filtration rate and an increase in the fractional excretion of Ca2+, Mg2+, and Pi. I/R injury affected the fibroblast growth factor 23 (FGF23)-klotho-vitamin D axis by increasing plasma levels of FGF23 and downregulation of renal klotho expression. Plasma levels of PTH and 1,25-dihydroxyvitamin D3 were unchanged. Further, downregulation of key genes for paracellular reabsorption of Ca2+ and Mg2+ (claudin (Cldn)2, Cldn10b, Cldn16, Cldn19) and for active transcellular transport of Ca2+, Mg2+, and Pi (calbindin-D28K, Ncx1, Pmca4, Cnnm2, Trpm7, NaPi-2a, and NaPi-2c) was observed. However, renal expression of Trpv5 and Trpv6 was increased. In vitro studies support a direct effect of proinflammatory cytokines on the mRNA expression of Cldn16, Cldn19, and Trpv6. Our findings indicate that renal I/R injury increases FGF23 blood levels independent of PTH and 1,25-dihydroxyvitamin D3. This increase is associated with hypermagnesemia, hyperphosphatemia, and increased or decreased expression of specific renal Ca2+, Mg2+, and Pi transporters, respectively.
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23
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Malek M. Brain consequences of acute kidney injury: Focusing on the hippocampus. Kidney Res Clin Pract 2018; 37:315-322. [PMID: 30619687 PMCID: PMC6312775 DOI: 10.23876/j.krcp.18.0056] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2018] [Revised: 07/19/2018] [Accepted: 07/31/2018] [Indexed: 12/11/2022] Open
Abstract
The high mortality rates associated with acute kidney injury are mainly due to extra-renal complications that occur following distant-organ involvement. Damage to these organs, which is commonly referred to as multiple organ dysfunction syndrome, has more severe and persistent effects. The brain and its sub-structures, such as the hippocampus, are vulnerable organs that can be adversely affected. Acute kidney injury may be associated with numerous brain and hippocampal complications, as it may alter the permeability of the blood-brain barrier. Although the pathogenesis of acute uremic encephalopathy is poorly understood, some of the underlying mechanisms that may contribute to hippocampal involvement include the release of multiple inflammatory mediators that coincide with hippocampus inflammation and cytotoxicity, neurotransmitter derangement, transcriptional dysregulation, and changes in the expression of apoptotic genes. Impairment of brain function, especially of a structure that has vital activity in learning and memory and is very sensitive to renal ischemic injury, can ultimately lead to cognitive and functional complications in patients with acute kidney injury. The objective of this review was to assess these complications in the brain following acute kidney injury, with a focus on the hippocampus as a critical region for learning and memory.
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Affiliation(s)
- Maryam Malek
- Department of Physiology, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran
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Abstract
Aims: This study aimed to assess whether neutrophil gelatinase-associated lipocalin (NGAL) and fibroblast growth factor 23 (FGF23) could be reliable biomarkers for early diagnosis of contrast-induced nephropathy (CIN). Methods: 202 patients who underwent percutaneous coronary intervention (PCI) were included in the research. All subjects were divided into CIN group and non-CIN group. Serum NGAL and FGF23 were evaluated before and 0, 1, and 2 days after PCI. Serum levels of these two markers were compared intra-group and among groups. Receiver-operating characteristic (ROC) analysis and logistic regression models were conducted to assess the diagnostic performance of NGAL and FGF23 in detecting CIN. Results: When compared with baseline values, serum levels of both NGAL and FGF23 in all subjects increased after PCI, and the values peaked 1 day after PCI, but the changing was greater in CIN group. There were obvious differences between two groups in serum NGAL after 1, 2 days, and similar differences present in serum FGF23 after 1 day. ROC analysis showed that the area under the curve (AUC) of relative values (percent change from the baseline) in NGAL after 1 day was 0.899 (95% CI: 0.834–0.964, p = .000), the optimum cutoff was 49% (sensitivity = 80%, specificity = 92.4%). And the AUC in FGF23 was 0.814 (95% CI: 0.733–0.894, p = .000), the optimum cutoff was 20% (sensitivity = 73.3%, specificity = 87.6%). Both serum NGAL and serum FGF23 could improve the clinical models in identifying CIN. Conclusions: NGAL and FGF23 may have certain value in early diagnosis of CIN.
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Affiliation(s)
- Huihui Li
- a Department of Nephropathy , Xiangya Hospital Central-South University , Changsha , Hunan 410008 , China
| | - Zaixin Yu
- b Department of Cardiology , Xiangya Hospital Central-South University , Changsha , Hunan 410008 , China
| | - Lu Gan
- a Department of Nephropathy , Xiangya Hospital Central-South University , Changsha , Hunan 410008 , China
| | - Ling Peng
- a Department of Nephropathy , Xiangya Hospital Central-South University , Changsha , Hunan 410008 , China
| | - Qiaoling Zhou
- a Department of Nephropathy , Xiangya Hospital Central-South University , Changsha , Hunan 410008 , China
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Outcome Prediction of Acute Kidney Injury Biomarkers at Initiation of Dialysis in Critical Units. J Clin Med 2018; 7:jcm7080202. [PMID: 30082648 PMCID: PMC6112021 DOI: 10.3390/jcm7080202] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2018] [Revised: 08/01/2018] [Accepted: 08/03/2018] [Indexed: 12/31/2022] Open
Abstract
: The ideal circumstances for whether and when to start RRT remain unclear. The outcome predictive ability of acute kidney injury (AKI) biomarkers measuring at dialysis initializing need more validation. This prospective, multi-center observational cohort study enrolled 257 patients with AKI undergoing renal replacement therapy (RRT) shortly after admission. At the start of RRT, blood and urine samples were collected for relevant biomarker measurement. RRT dependence and all-cause mortality were recorded up to 90 days after discharge. Areas under the receiver operator characteristic (AUROC) curves and a multivariate generalized additive model were applied to predict outcomes. One hundred and thirty-five (52.5%) patients died within 90 days of hospital discharge. Plasma c-terminal FGF-23 (cFGF-23) had the best discriminative ability (AUROC, 0.687) as compared with intact FGF-23 (iFGF-23) (AUROC, 0.504), creatinine-adjusted urine neutrophil gelatinase-associated lipocalin (AUROC, 0.599), and adjusted urine cFGF-23 (AUROC, 0.653) regardless whether patients were alive or not on day 90. Plasma cFGF-23 levels above 2050 RU/mL were independently associated with higher 90-day mortality (HR 1.76, p = 0.020). Higher cFGF-23 levels predicted less weaning from dialysis in survivors (HR, 0.62, p = 0.032), taking mortality as a competing risk. Adding cFGF-23 measurement to the AKI risk predicting score significantly improved risk stratification and 90-day mortality prediction (total net reclassification improvement = 0.148; p = 0.002). In patients with AKI who required RRT, increased plasma cFGF-23 levels correlated with higher 90-day overall mortality after discharge and predicted worse kidney recovery in survivors. When coupled to the AKI risk predicting score, cFGF-23 significantly improved mortality risk prediction. This observation adds evidence that cFGF-23 could be used as an optimal timing biomarker to initiate RRT.
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Sakan S, Premuzic V, Bandic Pavlovic D, Basic-Jukic N. Consequence of Elevated Fibroblast Growth Factor 23 Levels in Acute Kidney Injury, Renal Recovery and Overall Survival in Intensive Care Unit Patients After Major Surgery. Ther Apher Dial 2018; 22:544-551. [PMID: 30009421 DOI: 10.1111/1744-9987.12703] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2018] [Revised: 04/20/2018] [Accepted: 04/20/2018] [Indexed: 11/27/2022]
Abstract
The main goal of our study was to investigate the role of increased fibroblast growth factor 23 (FGF23) levels on renal recovery and overall survival. We conducted a prospective case-control cohort study, which included 121 adult cases who developed AKI after major surgical procedures. The subjects were followed-up until the last enrolled patient survived 180 days or until the time of death. Higher FGF23 levels positively correlated with serum creatinine levels (P < 0.05). Significantly higher number of patients without diuresis and with FGF23 ≤ 709 RU/mL survived when compared to patients without diuresis and with FGF23 ≥ 709 RU/mL (P < 0.001). FGF23 levels >709 RU/mL were a good predictive tool for overall mortality in a 6-month period (P < 0.05). This is the first study to analyze the impact of FGF23 values on short-term renal recovery and survival of patients with AKI after major surgery. The FGF23 increase related to AKI especially in more severe stages and in patients without diuresis is an independent risk factor for mortality.
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Affiliation(s)
- Sanja Sakan
- Clinical Department of Anesthesiology and Intensive Care, University Hospital Center Zagreb, Zagreb, Croatia
| | - Vedran Premuzic
- Department of Nephrology, Arterial Hypertension, Dialysis and Transplantation, University Hospital Center Zagreb, Zagreb, Croatia
| | - Daniela Bandic Pavlovic
- Clinical Department of Anesthesiology and Intensive Care, University Hospital Center Zagreb, Zagreb, Croatia.,School of Medicine, University of Zagreb, Zagreb, Croatia
| | - Nikolina Basic-Jukic
- Department of Nephrology, Arterial Hypertension, Dialysis and Transplantation, University Hospital Center Zagreb, Zagreb, Croatia.,School of Medicine, University of Zagreb, Zagreb, Croatia.,School of Medicine, University of Osijek, Osijek, Croatia
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Serum and urine FGF23 and IGFBP-7 for the prediction of acute kidney injury in critically ill children. BMC Pediatr 2018; 18:192. [PMID: 29907141 PMCID: PMC6004091 DOI: 10.1186/s12887-018-1175-y] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/27/2017] [Accepted: 06/11/2018] [Indexed: 01/17/2023] Open
Abstract
Background Fibroblast growth factor 23 (FGF23) and insulin-like growth factor binding protein 7 (IGFBP-7) are suggested to be biomarkers for predicting acute kidney injury (AKI). We compared them with proposed AKI biomarker of cystatin C (CysC), and aimed (1) to examine whether concentrations of these biomarkers vary with age, body weight, illness severity assessed by pediatric risk of mortality III score, and kidney function assessed by estimated glomerular filtration rate (eGFR), (2) to determine the association between these biomarkers and AKI, and (3) to evaluate whether these biomarkers could serve as early independent predictors of AKI in critically ill children. Methods This prospective single center study included 144 critically ill patients admitted to the pediatric intensive care unit (PICU) regardless of diagnosis. Serum and spot urine samples were collected during the first 24 h after PICU admission. AKI was diagnosed based on the AKI network (AKIN) criteria. Results Twenty-one patients developed AKI within 120 h of sample collection, including 11 with severe AKI defined as AKIN stages 2 and 3. Serum FGF23 levels were independently associated with eGFR after adjustment in a multivariate linear analysis (P < 0.001). Urinary IGFBP-7 (Adjusted OR = 2.94 per 1000 ng/mg increase, P = 0.035), serum CysC (Adjusted OR = 5.28, P = 0.005), and urinary CysC (Adjusted OR = 1.13 per 1000 ng/mg increase, P = 0.022) remained significantly associated with severe AKI after adjustment for body weight and illness severity, respectively. Urinary IGFBP-7 level was predictive of severe AKI and achieved the AUC of 0.79 (P = 0.001), but was not better than serum (AUC = 0.89, P < 0.001) and urinary (AUC = 0.88, P < 0.001) CysC in predicting severe AKI. Conclusions Serum FGF23 levels were inversely related to measures of eGFR. In contrast to serum and urinary FGF23 which are not associated with AKI in a general and heterogeneous PICU population, an increased urinary IGFBP-7 level was independently associated with the increased risk of severe AKI diagnosed within the next 5 days after sampling, but not superior to serum or urinary CysC in predicting severe AKI in critically ill children.
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Leaf DE, Siew ED, Eisenga MF, Singh K, Mc Causland FR, Srivastava A, Alp Ikizler T, Ware LB, Ginde AA, Kellum JA, Palevsky PM, Wolf M, Waikar SS. Fibroblast Growth Factor 23 Associates with Death in Critically Ill Patients. Clin J Am Soc Nephrol 2018; 13:531-541. [PMID: 29519954 PMCID: PMC5969465 DOI: 10.2215/cjn.10810917] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2017] [Accepted: 01/03/2018] [Indexed: 01/29/2023]
Abstract
BACKGROUND AND OBJECTIVES Dysregulated mineral metabolism is a common and potentially maladaptive feature of critical illness, especially in patients with AKI, but its association with death has not been comprehensively investigated. We sought to determine whether elevated plasma levels of the osteocyte-derived, vitamin D-regulating hormone, fibroblast growth factor 23 (FGF23), are prospectively associated with death in critically ill patients with AKI requiring RRT, and in a general cohort of critically ill patients with and without AKI. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS We measured plasma FGF23 and other mineral metabolite levels in two cohorts of critically ill patients (n=1527). We included 817 patients with AKI requiring RRT who enrolled in the ARF Trial Network (ATN) study, and 710 patients with and without AKI who enrolled in the Validating Acute Lung Injury biomarkers for Diagnosis (VALID) study. We hypothesized that higher FGF23 levels at enrollment are independently associated with higher 60-day mortality. RESULTS In the ATN study, patients in the highest compared with lowest quartiles of C-terminal (cFGF23) and intact FGF23 (iFGF23) had 3.84 (95% confidence interval, 2.31 to 6.41) and 2.08 (95% confidence interval, 1.03 to 4.21) fold higher odds of death, respectively, after adjustment for demographics, comorbidities, and severity of illness. In contrast, plasma/serum levels of parathyroid hormone, vitamin D metabolites, calcium, and phosphate were not associated with 60-day mortality. In the VALID study, patients in the highest compared with lowest quartiles of cFGF23 and iFGF23 had 3.52 (95% confidence interval, 1.96 to 6.33) and 1.93 (95% confidence interval, 1.12 to 3.33) fold higher adjusted odds of death. CONCLUSIONS Higher FGF23 levels are independently associated with greater mortality in critically ill patients.
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Affiliation(s)
- David E Leaf
- Due to the number of contributing authors, the affiliations are provided in the Supplemental Material
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Jung SY, Kwon J, Park S, Jhee JH, Yun HR, Kim H, Kee YK, Yoon CY, Chang TI, Kang EW, Park JT, Yoo TH, Kang SW, Han SH. Phosphate is a potential biomarker of disease severity and predicts adverse outcomes in acute kidney injury patients undergoing continuous renal replacement therapy. PLoS One 2018; 13:e0191290. [PMID: 29415048 PMCID: PMC5802883 DOI: 10.1371/journal.pone.0191290] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2017] [Accepted: 01/01/2018] [Indexed: 01/10/2023] Open
Abstract
Hyperphosphatemia is associated with mortality in patients with chronic kidney disease, and is common in critically ill patients with acute kidney injury (AKI); however, its clinical implication in these patients is unknown. We conducted an observational study in 1144 patients (mean age, 63.2 years; male, 705 [61.6%]) with AKI who received continuous renal replacement therapy (CRRT) between January 2009 and September 2016. Phosphate levels were measured before (0 h) and 24 h after CRRT initiation. We assessed disease severity using various clinical parameters. Phosphate at 0 h positively correlated with the Acute Physiology and Chronic Health Evaluation II (APACHE II; P < 0.001) and Sequential Organ Failure Assessment (SOFA; P < 0.001) scores, and inversely with mean arterial pressure (MAP; P = 0.02) and urine output (UO; P = 0.01). In a fully adjusted linear regression analysis for age, sex, Charlson comorbidity index (CCI), MAP, and estimated glomerular filtration rate (eGFR), higher 0 h phosphate level was significantly associated with high APACHE II (P < 0.001) and SOFA (P = 0.04) scores, suggesting that phosphate represents disease severity. A multivariable Cox model also showed that hyperphosphatemia was significantly associated with increased 28-day (HR 1.05, 95% CI 1.02-1.08, P = 0.001) and 90-day (HR 1.05, 95% CI 1.02-1.08, P = 0.001) mortality. Furthermore, patients with increased phosphate level during 24 h were at higher risk of death than those with stable or decreased phosphate levels. Finally, c-statistics significantly increased when phosphate was added to a model that included age, sex, CCI, body mass index, eGFR, MAP, hemoglobin, serum albumin, C-reactive protein, and APACHE II score. This study shows that phosphate is a potential biomarker that can reflect disease severity and predict mortality in critically ill patients receiving CRRT.
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Affiliation(s)
- Su-Young Jung
- Department of Internal Medicine, College of Medicine, Institute of Kidney Disease Research, Yonsei University, Seoul, Korea
| | - Jaeyeol Kwon
- Department of Internal Medicine, College of Medicine, Institute of Kidney Disease Research, Yonsei University, Seoul, Korea
| | - Seohyun Park
- Department of Internal Medicine, College of Medicine, Institute of Kidney Disease Research, Yonsei University, Seoul, Korea
| | - Jong Hyun Jhee
- Department of Internal Medicine, College of Medicine, Institute of Kidney Disease Research, Yonsei University, Seoul, Korea
| | - Hae-Ryong Yun
- Department of Internal Medicine, College of Medicine, Institute of Kidney Disease Research, Yonsei University, Seoul, Korea
| | - HyoungNae Kim
- Department of Internal Medicine, College of Medicine, Institute of Kidney Disease Research, Yonsei University, Seoul, Korea
| | - Youn Kyung Kee
- Department of Internal Medicine, College of Medicine, Institute of Kidney Disease Research, Yonsei University, Seoul, Korea
| | - Chang-Yun Yoon
- Department of Internal Medicine, College of Medicine, Institute of Kidney Disease Research, Yonsei University, Seoul, Korea
| | - Tae-Ik Chang
- Department of Internal Medicine, NHIS Medical Center, Ilsan Hospital, Ilsan, Korea
| | - Ea Wha Kang
- Department of Internal Medicine, NHIS Medical Center, Ilsan Hospital, Ilsan, Korea
| | - Jung Tak Park
- Department of Internal Medicine, College of Medicine, Institute of Kidney Disease Research, Yonsei University, Seoul, Korea
| | - Tae-Hyun Yoo
- Department of Internal Medicine, College of Medicine, Institute of Kidney Disease Research, Yonsei University, Seoul, Korea
| | - Shin-Wook Kang
- Department of Internal Medicine, College of Medicine, Institute of Kidney Disease Research, Yonsei University, Seoul, Korea
| | - Seung Hyeok Han
- Department of Internal Medicine, College of Medicine, Institute of Kidney Disease Research, Yonsei University, Seoul, Korea
- * E-mail:
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Toro L, Barrientos V, León P, Rojas M, Gonzalez M, González-Ibáñez A, Illanes S, Sugikawa K, Abarzúa N, Bascuñán C, Arcos K, Fuentealba C, Tong AM, Elorza AA, Pinto ME, Alzamora R, Romero C, Michea L. Erythropoietin induces bone marrow and plasma fibroblast growth factor 23 during acute kidney injury. Kidney Int 2018; 93:1131-1141. [PMID: 29395333 DOI: 10.1016/j.kint.2017.11.018] [Citation(s) in RCA: 71] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2017] [Revised: 10/26/2017] [Accepted: 11/09/2017] [Indexed: 12/13/2022]
Abstract
It is accepted that osteoblasts/osteocytes are the major source for circulating fibroblast growth factor 23 (FGF23). However, erythropoietic cells of bone marrow also express FGF23. The modulation of FGF23 expression in bone marrow and potential contribution to circulating FGF23 has not been well studied. Moreover, recent studies show that plasma FGF23 may increase early during acute kidney injury (AKI). Erythropoietin, a kidney-derived hormone that targets erythropoietic cells, increases in AKI. Here we tested whether an acute increase of plasma erythropoietin induces FGF23 expression in erythropoietic cells of bone marrow thereby contributing to the increase of circulating FGF23 in AKI. We found that erythroid progenitor cells of bone marrow express FGF23. Erythropoietin increased FGF23 expression in vivo and in bone marrow cell cultures via the homodimeric erythropoietin receptor. In experimental AKI secondary to hemorrhagic shock or sepsis in rodents, there was a rapid increase of plasma erythropoietin, and an induction of bone marrow FGF23 expression together with a rapid increase of circulating FGF23. Blockade of the erythropoietin receptor fully prevented the induction of bone marrow FGF23 and partially suppressed the increase of circulating FGF23. Finally, there was an early increase of both circulating FGF23 and erythropoietin in a cohort of patients with severe sepsis who developed AKI within 48 hours of admission. Thus, increases in plasma erythropoietin and erythropoietin receptor activation are mechanisms implicated in the increase of plasma FGF23 in AKI.
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Affiliation(s)
- Luis Toro
- Instituto de Ciencias Biomedicas, Facultad de Medicina, Universidad de Chile, Santiago, Chile; Division of Nephrology, Department of Medicine, Hospital Clinico Universidad de Chile, Santiago, Chile; Centro de Investigacion Clinica Avanzada, Hospital Clinico Universidad de Chile, Santiago, Chile
| | - Víctor Barrientos
- Instituto de Ciencias Biomedicas, Facultad de Medicina, Universidad de Chile, Santiago, Chile; Millennium Institute on Immunology and Immunotherapy, Santiago, Chile
| | - Pablo León
- Instituto de Ciencias Biomedicas, Facultad de Medicina, Universidad de Chile, Santiago, Chile
| | - Macarena Rojas
- Instituto de Ciencias Biomedicas, Facultad de Medicina, Universidad de Chile, Santiago, Chile
| | - Magdalena Gonzalez
- Instituto de Ciencias Biomedicas, Facultad de Medicina, Universidad de Chile, Santiago, Chile
| | - Alvaro González-Ibáñez
- Millennium Institute on Immunology and Immunotherapy, Santiago, Chile; Center for Biomedical Research, Faculty of Biological Sciences and Faculty of Medicine, Universidad Andrés Bello, Santiago, Chile
| | - Sebastián Illanes
- Department of Obstetrics and Gynaecology, Faculty of Medicine, Universidad de los Andes, Santiago, Chile
| | | | - Néstor Abarzúa
- Instituto de Ciencias Biomedicas, Facultad de Medicina, Universidad de Chile, Santiago, Chile
| | - César Bascuñán
- Instituto de Ciencias Biomedicas, Facultad de Medicina, Universidad de Chile, Santiago, Chile
| | - Katherine Arcos
- Instituto de Ciencias Biomedicas, Facultad de Medicina, Universidad de Chile, Santiago, Chile
| | - Carlos Fuentealba
- Instituto de Ciencias Biomedicas, Facultad de Medicina, Universidad de Chile, Santiago, Chile
| | - Ana María Tong
- Clinical Laboratory, Hospital Clinico Universidad de Chile, Santiago, Chile
| | - Alvaro A Elorza
- Millennium Institute on Immunology and Immunotherapy, Santiago, Chile; Center for Biomedical Research, Faculty of Biological Sciences and Faculty of Medicine, Universidad Andrés Bello, Santiago, Chile
| | | | - Rodrigo Alzamora
- Instituto de Ciencias Biomedicas, Facultad de Medicina, Universidad de Chile, Santiago, Chile; Millennium Nucleus of Ion Channel-Associated Diseases (MiNICAD), Santiago, Chile
| | - Carlos Romero
- Critical Care Unit, Department of Medicine, Hospital Clínico Universidad de Chile, Santiago, Chile
| | - Luis Michea
- Instituto de Ciencias Biomedicas, Facultad de Medicina, Universidad de Chile, Santiago, Chile; Division of Nephrology, Department of Medicine, Hospital Clinico Universidad de Chile, Santiago, Chile; Millennium Institute on Immunology and Immunotherapy, Santiago, Chile.
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Eren M, Place AT, Thomas PM, Flevaris P, Miyata T, Vaughan DE. PAI-1 is a critical regulator of FGF23 homeostasis. SCIENCE ADVANCES 2017; 3:e1603259. [PMID: 28924605 PMCID: PMC5597312 DOI: 10.1126/sciadv.1603259] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/22/2016] [Accepted: 08/11/2017] [Indexed: 05/29/2023]
Abstract
Elevated levels of fibroblast growth factor 23 (FGF23), a bone-derived phosphaturic hormone, are associated with a number of pathologic conditions including chronic kidney disease, cardiac hypertrophy, and congestive heart failure. Currently, there are no specific treatments available to lower plasma FGF23 levels. We have recently reported that genetic plasminogen activator inhibitor-1 (PAI-1) deficiency provided a significant reduction in circulating FGF23 levels while simultaneously prolonging the life span of Klotho-deficient mice. We extend our investigations into the effect of PAI-1 on FGF23 homeostasis. Transgenic overexpression of PAI-1 resulted in threefold increase in FGF23 levels compared to wild-type littermates. Moreover, pharmacological modulation of PAI-1 activity with the small-molecule PAI-1 antagonist TM5441 significantly reduced FGF23 levels in PAI-1 transgenic and Klotho-deficient mice. In addition, TM5441 treatment or PAI-1 deficiency significantly accelerated the clearance of endogenous FGF23 and recombinant human FGF23 from circulation in mice with acute kidney injury. On the basis of these observations, we studied the effects of plasminogen activators (PAs), tissue-type PA (tPA) and urokinase-type PA (uPA), on FGF23. We demonstrate that both PAs directly cleave FGF23; however, it is not known whether the PA-generated FGF23 peptides retain or acquire functions that affect binding and/or signaling properties of intact FGF23. PAI-1 inhibits the PA-dependent cleavage of FGF23, and TM5441 inhibition of PAI-1 restores the proteolysis of FGF23. Furthermore, top-down proteomic analysis indicates that tPA cleaves FGF23 at multiple arginines including the proconvertase sensitive site R176. In summary, our results indicate that PAI-1 prevents the PA-driven proteolysis of FGF23 and PAI-1 inhibition provides a novel therapeutic approach to prevent the pathologic consequences of increased FGF23.
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Affiliation(s)
- Mesut Eren
- Department of Medicine, Northwestern University Feinberg School of Medicine, Chicago, IL 60611, USA
- Feinberg Cardiovascular Research Institute, Northwestern University Feinberg School of Medicine, Chicago, IL 60611, USA
| | - Aaron T. Place
- Department of Medicine, Northwestern University Feinberg School of Medicine, Chicago, IL 60611, USA
- Feinberg Cardiovascular Research Institute, Northwestern University Feinberg School of Medicine, Chicago, IL 60611, USA
| | - Paul M. Thomas
- Proteomics Center of Excellence, Northwestern University Feinberg School of Medicine, Chicago, IL 60611, USA
| | - Panagiotis Flevaris
- Department of Medicine, Northwestern University Feinberg School of Medicine, Chicago, IL 60611, USA
- Feinberg Cardiovascular Research Institute, Northwestern University Feinberg School of Medicine, Chicago, IL 60611, USA
| | - Toshio Miyata
- United Centers for Advanced Research and Translational Medicine, Tohoku University Graduate School of Medicine, Miyagi, Japan
| | - Douglas E. Vaughan
- Department of Medicine, Northwestern University Feinberg School of Medicine, Chicago, IL 60611, USA
- Feinberg Cardiovascular Research Institute, Northwestern University Feinberg School of Medicine, Chicago, IL 60611, USA
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Lim AKH. Transient secondary hyperparathyroidism in acute kidney injury. Intern Med J 2017; 46:857-8. [PMID: 27405896 DOI: 10.1111/imj.13095] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2015] [Accepted: 02/04/2016] [Indexed: 12/31/2022]
Affiliation(s)
- A K H Lim
- Department of General Medicine, Monash Health, Melbourne, Victoria, Australia.,Department of Nephrology, Monash Health, Melbourne, Victoria, Australia.,School of Clinical Sciences, Monash University Department of Medicine, Monash Health, Melbourne, Victoria, Australia
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Kanbay M, Vervloet M, Cozzolino M, Siriopol D, Covic A, Goldsmith D, Solak Y. Novel Faces of Fibroblast Growth Factor 23 (FGF23): Iron Deficiency, Inflammation, Insulin Resistance, Left Ventricular Hypertrophy, Proteinuria and Acute Kidney Injury. Calcif Tissue Int 2017; 100:217-228. [PMID: 27826644 DOI: 10.1007/s00223-016-0206-7] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/08/2016] [Accepted: 10/31/2016] [Indexed: 12/21/2022]
Abstract
FGF23 is a hormone that appears as the core regulator of phosphate metabolism. Great deal of data has accumulated to demonstrate increased FGF23 secretion from the bone to compensate for even subtle increases in serum phosphorus long before intact PTH. However, recent evidence points to the fact that actions and interactions of FGF23 are not limited solely to phosphate metabolism. FGF23 may be implicated in iron metabolism and erythropoiesis, inflammation, insulin resistance, proteinuria, acute kidney injury and left ventricular hypertrophy. In this review, we will summarize latest experimental and clinical data examining impact of FGF23 on aforementioned pathophysiologic pathways/disorders.
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Affiliation(s)
- Mehmet Kanbay
- Division of Nephrology, Department of Medicine, Koc University School of Medicine, Sariyer, Istanbul, Turkey.
| | - Marc 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
| | - Mario Cozzolino
- Renal Unit, San Paolo Hospital Milan, Department of Health and Science, University of Milan, Milan, Italy
| | - Dimitrie Siriopol
- Nephrology Clinic, Dialysis and Renal Transplant Center, 'C.I. PARHON' University Hospital, 'Grigore T. Popa' University of Medicine, Iasi, Romania
| | - Adrian Covic
- Nephrology Clinic, Dialysis and Renal Transplant Center, 'C.I. PARHON' University Hospital, 'Grigore T. Popa' University of Medicine, Iasi, Romania
| | - David Goldsmith
- Renal and Transplantation Department, Guy's and St Thomas' Hospitals, London, UK
| | - Yalcin Solak
- Department of Nephrology, Sakarya Training and Research Hospital, Sakarya, Turkey
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The effect of nephrectomy on Klotho, FGF-23 and bone metabolism. Int Urol Nephrol 2017; 49:681-688. [PMID: 28130714 PMCID: PMC5357491 DOI: 10.1007/s11255-017-1519-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2016] [Accepted: 01/17/2017] [Indexed: 01/12/2023]
Abstract
Background Increased concentration of fibroblast growth factor 23 (FGF-23) and decreased levels of soluble Klotho (sKL) are linked to negative clinical outcomes among patients with chronic kidney disease and acute kidney injury. Therefore, it is reasonable to hypothesize that GFR reduction caused by nephrectomy might alter mineral metabolism and induces adverse consequences. Whether nephrectomy due to urological indications causes derangements in FGF-23 and sKL has not been studied. The aim of the study was to evaluate the effect of acute GFR decline due to unilateral nephrectomy on bone metabolism, FGF-23 and sKL levels. Methods This is a prospective, single-centre observational study of patients undergoing nephrectomy due to urological indications. Levels of C-terminal FGF-23 (c-FGF-23), sKL and bone turnover markers [β-crosslaps (CTX), bone-specific alkaline phosphatase (bALP) and tartrate-resistant acid phosphatase 5b (TRAP 5b)] were measured before and after surgery (5 ± 2 days). Results Twenty-nine patients were studied (14 females, age 63.0 ± 11.6, eGFR 87.3 ± 19.2 ml/min/1.73 m2). After surgery, eGFR significantly declined (p < 0.0001). Nephrectomy significantly decreased sKL level [709.8 (599.9–831.2) vs. 583.0 (411.7–752.6) pg/ml, p < 0.001] and did not change c-FGF-23 concentration [70.5 (49.8–103.3) vs. 77.1 (60.5–109.1) RU/ml, p = 0.9]. Simultaneously, alterations in bone turnover markers were observed. Serum concentration of CTX increased [0.49 (0.4–0.64) vs. 0.59 (0.46–0.85) ng/ml, p = 0.001], while bALP and TRAP 5b decreased [23.6 (18.8–31.4) vs. 17.9 (15.0–22.0) U/l, p < 0.0001 and 3.3 (3.0–3.7) vs. 2.8 (2.3–3.2) U/l, p < 0.001, respectively]. Conclusions Nephrectomy among patients with preserved renal function before surgery does not increase c-FGF-23 but reduces sKL. Moreover, nephrectomy results in derangements in bone turnover markers in short-term follow-up. These changes may participate in pathogenesis of bone disease after nephrectomy.
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Hanudel MR, Wesseling-Perry K, Gales B, Ramos G, Campbell V, Ethridge K, Scotti M, Elashoff DA, Alejos J, Reemtsen B, Salusky IB. Effects of acute kidney injury and chronic hypoxemia on fibroblast growth factor 23 levels in pediatric cardiac surgery patients. Pediatr Nephrol 2016; 31:661-9. [PMID: 26525200 PMCID: PMC4766020 DOI: 10.1007/s00467-015-3257-5] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/17/2015] [Revised: 10/20/2015] [Accepted: 10/20/2015] [Indexed: 01/07/2023]
Abstract
BACKGROUND Fibroblast growth factor-23 (FGF23) levels are elevated in cardiopulmonary bypass (CPB)-associated acute kidney injury (AKI); however, it is unknown how much of the circulating FGF23 is intact and bioactive. Hypoxia may induce FGF23 production, yet its impact in humans is unknown. Pediatric cardiac surgery patients have both a high incidence of CPB-associated AKI and a high prevalence of chronic hypoxemia. METHODS We assessed the effects of hypoxemia and CPB-associated AKI on C-terminal FGF23 (cFGF23) and intact FGF23 (iFGF23) levels in 32 pediatric cardiac surgery patients with normal estimated glomerular filtration rate (eGFR). Plasma cFGF23 and iFGF23 were measured preoperatively and serially postoperatively. RESULTS Despite normal renal and ventricular function, preoperative cFGF23 levels were high and elevated out of proportion to iFGF23 levels. Preoperative oxygen saturation measurements correlated inversely with FGF23 levels. Preoperative cFGF23 and oxygen saturation both predicted postoperative AKI. Postoperatively, cFGF23 and iFGF23 increased by 2 h postreperfusion; iFGF23 then returned to baseline, but cFGF23 remained elevated through 24 h postreperfusion. Group status (AKI vs. non-AKI) modified the effect of time on changes in iFGF23 levels but not cFGF23 levels. CONCLUSIONS Preoperative cFGF23 may predict CPB-associated kidney dysfunction. Changes over time in cFGF23 and iFGF23 levels post-CPB differ. Chronic hypoxemia may affect FGF23 production in humans.
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Affiliation(s)
- Mark R. Hanudel
- Department of Pediatrics, David Geffen School of Medicine at UCLA, Los Angeles, CA
| | | | - Barbara Gales
- Department of Pediatrics, David Geffen School of Medicine at UCLA, Los Angeles, CA
| | - Georgina Ramos
- Department of Pediatrics, David Geffen School of Medicine at UCLA, Los Angeles, CA
| | - Vicky Campbell
- Department of Pediatrics, David Geffen School of Medicine at UCLA, Los Angeles, CA
| | - Kristen Ethridge
- Department of Pediatrics, David Geffen School of Medicine at UCLA, Los Angeles, CA
| | - Mary Scotti
- Department of Pediatrics, David Geffen School of Medicine at UCLA, Los Angeles, CA
| | - David A. Elashoff
- Department of Medicine, David Geffen School of Medicine at UCLA, Los Angeles, CA
| | - Juan Alejos
- Department of Pediatrics, David Geffen School of Medicine at UCLA, Los Angeles, CA
| | - Brian Reemtsen
- Department of Surgery, David Geffen School of Medicine at UCLA, Los Angeles, CA
| | - Isidro B. Salusky
- Department of Pediatrics, David Geffen School of Medicine at UCLA, Los Angeles, CA
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Leaf DE, Christov M, Jüppner H, Siew E, Ikizler TA, Bian A, Chen G, Sabbisetti VS, Bonventre JV, Cai X, Wolf M, Waikar SS. Fibroblast growth factor 23 levels are elevated and associated with severe acute kidney injury and death following cardiac surgery. Kidney Int 2016; 89:939-48. [PMID: 26924052 DOI: 10.1016/j.kint.2015.12.035] [Citation(s) in RCA: 67] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2015] [Revised: 11/24/2015] [Accepted: 12/03/2015] [Indexed: 10/22/2022]
Abstract
Fibroblast growth factor 23 (FGF23) is elevated in chronic kidney disease and associated with increased mortality, but data on FGF23 in humans with acute kidney injury (AKI) are limited. Here we tested whether FGF23 levels rise early in the course of AKI following cardiac surgery and if higher postoperative FGF23 levels are independently associated with severe AKI and adverse outcomes. Plasma C-terminal FGF23 (cFGF23) levels were measured preoperatively, at the end of cardiopulmonary bypass, and on postoperative days 1 and 3 in 250 patients undergoing cardiac surgery. We also measured intact FGF23, parathyroid hormone, phosphate, and vitamin D metabolites in a subgroup of 18 patients with severe AKI and 18 matched non-AKI controls. Beginning at the end of cardiopulmonary bypass, cFGF23 levels were significantly and consistently higher in patients who developed AKI compared with those who did not. The early increase in cFGF23 predated changes in other mineral metabolites. The levels of intact FGF23 also increased in patients who developed severe AKI, but the magnitude was lower than cFGF23. In analyses adjusted for age, preoperative eGFR, and cardiopulmonary bypass time, higher cFGF23 levels at the end of cardiopulmonary bypass were significantly associated with greater risk of severe AKI and the need for renal replacement therapy or death. Thus, cFGF23 levels rise early in AKI following cardiac surgery and are independently associated with adverse postoperative outcomes.
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Affiliation(s)
- David E Leaf
- Division of Renal Medicine, Brigham and Women's Hospital, Boston, Massachusetts, USA.
| | - Marta Christov
- Endocrine Unit and Pediatric Nephrology Unit, Massachusetts General Hospital, Boston, Massachusetts, USA; Department of Medicine, New York Medical College, Valhalla, NY
| | - Harald Jüppner
- Endocrine Unit and Pediatric Nephrology Unit, Massachusetts General Hospital, Boston, Massachusetts, USA
| | - Edward Siew
- Division of Nephrology and Hypertension, Vanderbilt Center for Kidney Disease, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - T Alp Ikizler
- Division of Nephrology and Hypertension, Vanderbilt Center for Kidney Disease, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - Aihua Bian
- Department of Biostatistics, Vanderbilt Center for Kidney Disease, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - Guanhua Chen
- Department of Biostatistics, Vanderbilt Center for Kidney Disease, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - Venkata S Sabbisetti
- Division of Renal Medicine, Brigham and Women's Hospital, Boston, Massachusetts, USA
| | - Joseph V Bonventre
- Division of Renal Medicine, Brigham and Women's Hospital, Boston, Massachusetts, USA
| | - Xuan Cai
- Division of Nephrology, Department of Medicine and Center for Translational Metabolism and Health, Institute for Public Health and Medicine, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, USA
| | - Myles Wolf
- Division of Nephrology, Department of Medicine and Center for Translational Metabolism and Health, Institute for Public Health and Medicine, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, USA
| | - Sushrut S Waikar
- Division of Renal Medicine, Brigham and Women's Hospital, Boston, Massachusetts, USA
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Neyra JA, Moe OW, Hu MC. Fibroblast growth factor 23 and acute kidney injury. Pediatr Nephrol 2015; 30:1909-18. [PMID: 25480729 PMCID: PMC4458234 DOI: 10.1007/s00467-014-3006-1] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/22/2014] [Revised: 11/03/2014] [Accepted: 11/04/2014] [Indexed: 02/07/2023]
Abstract
Fibroblast growth factor 23 (FGF23), which is produced in bone, participates in the maintenance of phosphate metabolism and can serve as a biomarker for adverse cardiovascular outcomes in patients with chronic kidney disease and end-stage renal disease. Circulating FGF23 rapidly increases after acute kidney injury (AKI), preceding other known markers such as neutrophil gelatinase-associated lipocalin and serum creatinine. The increase in FGF23 in AKI appears to be independent of parathyroid hormone, vitamin D signaling pathways, and dietary phosphate. The potential mechanisms include: (1) increased production of FGF23 in the bone by yet-to-be-identified factors; (2) ectopic production of FGF23 by injured renal tubules; and (3) decreased renal clearance of circulating FGF23. Circulating FGF23 determined by intact FGF23 enzyme-linked immunosorbent assay (ELISA) is a more reliable biomarker of AKI than FGF23 C-terminal ELISA (a mixed readout of C-terminal fragment and intact FGF23). Given that FGF23 can be ectopically expressed in differentiated renal tubules and iron modulates FGF23 metabolism, an effect of iron on FGF23 expression in renal tubules is conceivable but remains to be confirmed. More clinical and experimental studies are required to validate the use of circulating FGF23 as a biomarker for the early identification of AKI and prediction of short- and long-term adverse outcomes post-AKI. More importantly, the biologic effect of increased FGF23 in AKI needs to be defined.
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Affiliation(s)
- Javier A Neyra
- Department of Internal Medicine, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd, Dallas, TX, 75390-885, USA
| | - Orson W Moe
- Department of Internal Medicine, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd, Dallas, TX, 75390-885, USA
- Department of Physiology, University of Texas Southwestern Medical Center, Dallas, TX, USA
- Charles and Jane Pak Center for Mineral Metabolism and Clinical Research, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd, Dallas, TX, 75390-885, USA
| | - Ming Chang Hu
- Department of Internal Medicine, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd, Dallas, TX, 75390-885, USA.
- Charles and Jane Pak Center for Mineral Metabolism and Clinical Research, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd, Dallas, TX, 75390-885, USA.
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FGF23 in Acute and Chronic Illness. DISEASE MARKERS 2015; 2015:358086. [PMID: 26491212 PMCID: PMC4600945 DOI: 10.1155/2015/358086] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/09/2015] [Revised: 09/03/2015] [Accepted: 09/06/2015] [Indexed: 12/31/2022]
Abstract
FGF23 is a bone-derived phosphaturic hormone that may become a useful biomarker for the identification of high-risk patients in chronic but also acute disease. It rises early in chronic kidney disease and is strongly and independently associated with excess morbidity and mortality. Emerging data suggest that FGF23 is also elevated in different scenarios of acute illness. In this review, we give an overview on the role of this interesting disease marker and potential and proven interventional strategies and discuss a blueprint for future research.
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Abstract
High circulating levels of fibroblast growth factor 23 (FGF23) have been demonstrated in kidney failure, but mechanisms of this are not well understood. Here we examined the impact of the kidney on the early regulation of intact FGF23 in acute uremia as induced by bilateral or unilateral nephrectomy (BNX and UNX, respectively) in the rat. BNX induced a significant increase in plasma intact FGF23 levels from 112 to 267 pg/ml within 15 min, which remained stable thereafter. UNX generated intact FGF23 levels between that seen in BNX and sham-operated rats. The intact to C-terminal FGF23 ratio was significantly increased in BNX rats. The rapid rise in FGF23 after BNX was independent of parathyroid hormone or FGF receptor signaling. No evidence of early stimulation of FGF23 gene expression in the bone was found. Furthermore, acute severe hyperphosphatemia or hypercalcemia had no impact on intact FGF23 levels in normal and BNX rats. The half-life of exogenous recombinant human FGF23 was significantly prolonged from 4.4 to 11.8 min in BNX rats. Measurements of plasma FGF23 in the renal artery and renal vein demonstrated a significant renal extraction. Thus the kidney is important in FGF23 homeostasis by regulation of its plasma level and metabolism.
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Kangelaris KN, Prakash A, Liu KD, Aouizerat B, Woodruff PG, Erle DJ, Rogers A, Seeley EJ, Chu J, Liu T, Osterberg-Deiss T, Zhuo H, Matthay MA, Calfee CS. Increased expression of neutrophil-related genes in patients with early sepsis-induced ARDS. Am J Physiol Lung Cell Mol Physiol 2015; 308:L1102-13. [PMID: 25795726 DOI: 10.1152/ajplung.00380.2014] [Citation(s) in RCA: 114] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2014] [Accepted: 03/16/2015] [Indexed: 01/10/2023] Open
Abstract
The early sequence of events leading to the development of the acute respiratory distress syndrome (ARDS) in patients with sepsis remains inadequately understood. The purpose of this study was to identify changes in gene expression early in the course of illness, when mechanisms of injury may provide the most relevant treatment and prognostic targets. We collected whole blood RNA in critically ill patients admitted from the Emergency Department to the intensive care unit within 24 h of admission at a tertiary care center. Whole genome expression was compared in patients with sepsis and ARDS to patients with sepsis alone. We selected genes with >1 log2 fold change and false discovery rate <0.25, determined their significance in the literature, and performed pathway analysis. Several genes were upregulated in 29 patients with sepsis with ARDS compared with 28 patients with sepsis alone. The most differentially expressed genes included key mediators of the initial neutrophil response to infection: olfactomedin 4, lipocalin 2, CD24, and bactericidal/permeability-increasing protein. These gene expression differences withstood adjustment for age, sex, study batch, white blood cell count, and presence of pneumonia or aspiration. Pathway analysis demonstrated overrepresentation of genes involved in known respiratory and infection pathways. These data indicate that several neutrophil-related pathways may be involved in the early pathogenesis of sepsis-related ARDS. In addition, identifiable gene expression differences occurring early in the course of sepsis-related ARDS may further elucidate understanding of the neutrophil-related mechanisms in progression to ARDS.
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Affiliation(s)
- Kirsten Neudoerffer Kangelaris
- Department of Medicine, Division of Hospital Medicine, University of California-San Francisco, San Francisco, California;
| | - Arun Prakash
- Departments of Medicine and Anesthesia, University of California-San Francisco, San Francisco, California
| | - Kathleen D Liu
- Departments of Medicine and Anesthesia, University of California-San Francisco, San Francisco, California; Cardiovascular Research Institute, University of California-San Francisco, San Francisco, California
| | - Bradley Aouizerat
- Department of Physiologic Nursing, University of California-San Francisco, San Francisco, California; Institute for Human Genetics, University of California-San Francisco, San Francisco, California
| | - Prescott G Woodruff
- Departments of Medicine and Anesthesia, University of California-San Francisco, San Francisco, California; Department of Medicine, Division of Pulmonary, Critical Care, Allergy and Sleep Medicine, University of California-San Francisco, San Francisco, California; and
| | - David J Erle
- Department of Medicine, Division of Pulmonary, Critical Care, Allergy and Sleep Medicine, University of California-San Francisco, San Francisco, California; and
| | - Angela Rogers
- Department of Medicine, Division of Pulmonary, Critical Care, Allergy and Sleep Medicine, University of California-San Francisco, San Francisco, California; and Department of Pulmonary and Critical Care, Stanford University, Stanford, California
| | - Eric J Seeley
- Department of Medicine, Division of Pulmonary, Critical Care, Allergy and Sleep Medicine, University of California-San Francisco, San Francisco, California; and
| | - Jeffrey Chu
- Departments of Medicine and Anesthesia, University of California-San Francisco, San Francisco, California
| | - Tom Liu
- Departments of Medicine and Anesthesia, University of California-San Francisco, San Francisco, California
| | - Thomas Osterberg-Deiss
- Departments of Medicine and Anesthesia, University of California-San Francisco, San Francisco, California
| | - Hanjing Zhuo
- Departments of Medicine and Anesthesia, University of California-San Francisco, San Francisco, California
| | - Michael A Matthay
- Departments of Medicine and Anesthesia, University of California-San Francisco, San Francisco, California; Cardiovascular Research Institute, University of California-San Francisco, San Francisco, California; Department of Medicine, Division of Pulmonary, Critical Care, Allergy and Sleep Medicine, University of California-San Francisco, San Francisco, California; and
| | - Carolyn S Calfee
- Departments of Medicine and Anesthesia, University of California-San Francisco, San Francisco, California; Cardiovascular Research Institute, University of California-San Francisco, San Francisco, California; Department of Medicine, Division of Pulmonary, Critical Care, Allergy and Sleep Medicine, University of California-San Francisco, San Francisco, California; and
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Leaf DE, Raed A, Donnino MW, Ginde AA, Waikar SS. Reply: active and native vitamin D in critical illness. Am J Respir Crit Care Med 2015; 190:1194-6. [PMID: 25398113 DOI: 10.1164/rccm.201408-1454le] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Affiliation(s)
- David E Leaf
- 1 Brigham and Women's Hospital Boston, Massachusetts
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Abstract
PURPOSE OF REVIEW To review the emerging literature on changes in fibroblast growth factor 23 (FGF23) levels in the setting of acute kidney injury (AKI). RECENT FINDINGS Studies suggest that FGF23 levels are elevated in patients with AKI and correlate with increased risk of death or need for dialysis in adults, or prolonged ventilation time and higher fluid gain in children. Animal studies have shown that the cause behind this FGF23 increase is multifactorial and includes increased production in bone and decreased clearance, but not vitamin D or parathyroid hormone (PTH) activated pathways. Interestingly, FGF23 levels are found to be mildly elevated even in hospitalized patients without kidney injury, although this observation may be limited to only c-terminal FGF23 fragments. The prognostic implications of an elevated FGF23 value in patients with AKI need to be confirmed in larger cohorts and evaluated for long-term outcomes such as the development of new chronic kidney disease (CKD) or CKD progression, as well as cardiovascular disease, similar to the studies of FGF23 in the prevalent CKD population. SUMMARY FGF23 levels are elevated in patients with AKI and are associated with morbidity and mortality in small human studies. Mechanistic work in animals suggests that the elevation is independent of PTH or vitamin D signaling pathways. Much work remains to understand the physiology behind FGF23 elevation and the long-term effects of FGF23 in AKI.
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Matheny ME, Peterson JF, Eden SK, Hung AM, Speroff T, Abdel-Kader K, Parr SK, Ikizler TA, Siew ED. Laboratory test surveillance following acute kidney injury. PLoS One 2014; 9:e103746. [PMID: 25117447 PMCID: PMC4130516 DOI: 10.1371/journal.pone.0103746] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2014] [Accepted: 07/01/2014] [Indexed: 01/25/2023] Open
Abstract
BACKGROUND Patients with hospitalized acute kidney injury (AKI) are at increased risk for accelerated loss of kidney function, morbidity, and mortality. We sought to inform efforts at improving post-AKI outcomes by describing the receipt of renal-specific laboratory test surveillance among a large high-risk cohort. METHODS We acquired clinical data from the Electronic health record (EHR) of 5 Veterans Affairs (VA) hospitals to identify patients hospitalized with AKI from January 1st, 2002 to December 31st, 2009, and followed these patients for 1 year or until death, enrollment in palliative care, or improvement in renal function to estimated GFR (eGFR) ≥ 60 L/min/1.73 m(2). Using demographic data, administrative codes, and laboratory test data, we evaluated the receipt and timing of outpatient testing for serum concentrations of creatinine and any as well as quantitative proteinuria recommended for CKD risk stratification. Additionally, we reported the rate of phosphorus and parathyroid hormone (PTH) monitoring recommended for chronic kidney disease (CKD) patients. RESULTS A total of 10,955 patients admitted with AKI were discharged with an eGFR<60 mL/min/1.73 m2. During outpatient follow-up at 90 and 365 days, respectively, creatinine was measured on 69% and 85% of patients, quantitative proteinuria was measured on 6% and 12% of patients, PTH or phosphorus was measured on 10% and 15% of patients. CONCLUSIONS Measurement of creatinine was common among all patients following AKI. However, patients with AKI were infrequently monitored with assessments of quantitative proteinuria or mineral metabolism disorder, even for patients with baseline kidney disease.
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Affiliation(s)
- Michael E. Matheny
- Geriatrics Research Education & Clinical Center (GRECC), Tennessee Valley Healthcare System (TVHS), Veteran's Health Administration, Nashville, TN, United States of America
- Department of Biomedical Informatics, Vanderbilt University School of Medicine, Nashville, TN, United States of America
- Division of General Internal Medicine, Department of Medicine, Vanderbilt University School of Medicine, Nashville, TN, United States of America
- Department of Biostatistics, Vanderbilt University School of Medicine, Nashville, TN, United States of America
| | - Josh F. Peterson
- Department of Biomedical Informatics, Vanderbilt University School of Medicine, Nashville, TN, United States of America
- Division of General Internal Medicine, Department of Medicine, Vanderbilt University School of Medicine, Nashville, TN, United States of America
| | - Svetlana K. Eden
- Department of Biostatistics, Vanderbilt University School of Medicine, Nashville, TN, United States of America
| | - Adriana M. Hung
- Geriatrics Research Education & Clinical Center (GRECC), Tennessee Valley Healthcare System (TVHS), Veteran's Health Administration, Nashville, TN, United States of America
- Division of Nephrology, Department of Medicine, Vanderbilt University School of Medicine, Nashville, TN, United States of America
| | - Theodore Speroff
- Geriatrics Research Education & Clinical Center (GRECC), Tennessee Valley Healthcare System (TVHS), Veteran's Health Administration, Nashville, TN, United States of America
- Division of General Internal Medicine, Department of Medicine, Vanderbilt University School of Medicine, Nashville, TN, United States of America
- Department of Biostatistics, Vanderbilt University School of Medicine, Nashville, TN, United States of America
| | - Khaled Abdel-Kader
- Division of Nephrology, Department of Medicine, Vanderbilt University School of Medicine, Nashville, TN, United States of America
| | - Sharidan K. Parr
- Division of Nephrology, Department of Medicine, Vanderbilt University School of Medicine, Nashville, TN, United States of America
| | - T. Alp Ikizler
- Division of Nephrology, Department of Medicine, Vanderbilt University School of Medicine, Nashville, TN, United States of America
| | - Edward D. Siew
- Division of Nephrology, Department of Medicine, Vanderbilt University School of Medicine, Nashville, TN, United States of America
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Wang WJ, Chao CT, Huang YC, Wang CY, Chang CH, Huang TM, Lai CF, Huang HY, Shiao CC, Chu TS, Chen YM, Wu VC, Ko WJ, Wu KD. The impact of acute kidney injury with temporary dialysis on the risk of fracture. J Bone Miner Res 2014; 29:676-84. [PMID: 23929760 DOI: 10.1002/jbmr.2061] [Citation(s) in RCA: 73] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/20/2013] [Revised: 07/22/2013] [Accepted: 07/29/2013] [Indexed: 12/21/2022]
Abstract
Acute kidney injury (AKI) has a negative impact on long-term renal function and prognosis. However, the association between acute renal dysfunction and long-term effects on bone disorders has not yet been characterized. Using a population-based cohort study, we aimed to evaluate associations between AKI and long-term effects on bone fractures. We identified relevant data of all hospitalized patients aged >18 years with histories of dialysis-requiring AKI, with subsequent recovery and discharge, from the claim records of the Taiwan National Health Insurance database between 2000 and 2008. We determined long-term de novo bone fracture and all-cause mortality after patients' index-hospitalization discharge using propensity score-adjusted Cox proportional hazard model. Varying-time models were used to adjust for long-term effects of end-stage renal disease (ESRD) on main outcomes. Among 448 AKI patients who had dialysis and survived 90 days after index-hospitalization discharge without reentering dialysis, 273 were male (60.9%) with a mean age of 61.4 ± 16.6 years. Controls included 1792 hospitalized patients without AKI, dialysis, or bone fracture history. In the AKI recovery group, bone fracture incidence was 320 per 10,000 person-years and hazard ratio (HR) of long-term bone fracture was 1.25 (p = 0.049) compared with the control group, independent of subsequent ESRD status (HR = 1.55; p = 0.01). Both AKI recovery status (HR = 2.31; p < 0.001) and time varying factor of bone fracture (HR = 1.43; p < 0.001) were independent predictors of mortality compared with controls. In conclusion, AKI requiring temporary dialysis independently increases long-term risk of bone fracture, regardless of subsequent progression to ESRD. Long-term bone fractures may negatively impact patient mortality.
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Affiliation(s)
- Wei-Jie Wang
- Department of Internal Medicine, Tao-Yuan General Hospital, Tao-Yuan County, Taiwan
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Wu VC, Wu CH, Huang TM, Wang CY, Lai CF, Shiao CC, Chang CH, Lin SL, Chen YY, Chen YM, Chu TS, Chiang WC, Wu KD, Tsai PR, Chen L, Ko WJ. Long-term risk of coronary events after AKI. J Am Soc Nephrol 2014; 25:595-605. [PMID: 24503241 DOI: 10.1681/asn.2013060610] [Citation(s) in RCA: 245] [Impact Index Per Article: 24.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
The incidence rate of AKI in hospitalized patients is increasing. However, relatively little attention has been paid to the association of AKI with long-term risk of adverse coronary events. Our study investigated hospitalized patients who recovered from de novo dialysis-requiring AKI between 1999 and 2008 using patient data collected from inpatient claims from Taiwan National Health Insurance. We used Cox regression with time-varying covariates to adjust for subsequent CKD and ESRD after discharge. Results were further validated by analysis of a prospectively constructed database. Among 17,106 acute dialysis patients who were discharged, 4869 patients recovered from dialysis-requiring AKI (AKI recovery group) and were matched with 4869 patients without AKI (non-AKI group). The incidence rates of coronary events were 19.8 and 10.3 per 1000 person-years in the AKI recovery and non-AKI groups, respectively. AKI recovery associated with higher risk of coronary events (hazard ratio [HR], 1.67; 95% confidence interval [95% CI], 1.36 to 2.04) and all-cause mortality (HR, 1.67; 95% CI, 1.57 to 1.79) independent of the effects of subsequent progression to CKD and ESRD. The risk levels of de novo coronary events after hospital discharge were similar in patients with diabetes alone and patients with AKI alone (P=0.23). Our results reveal that AKI with recovery associated with higher long-term risks of coronary events and death in this cohort, suggesting that AKI may identify patients with high risk of future coronary events. Enhanced postdischarge follow-up of renal function of patients who have recovered from temporary dialysis may be warranted.
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Affiliation(s)
- Vin-Cent Wu
- Division of Nephrology, Department of Internal Medicine
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Vijayan A, Li T, Dusso A, Jain S, Coyne DW. Relationship of 1,25 dihydroxy Vitamin D Levels to Clinical Outcomes in Critically Ill Patients with Acute Kidney Injury. ACTA ACUST UNITED AC 2014; 5. [PMID: 26295008 DOI: 10.4172/2161-0959.1000190] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
BACKGROUND Calcitriol [1,25(OH)2D] plays a central role in endocrine regulation of bone and mineral metabolism. Low 1,25(OH)2D levels in chronic kidney disease (CKD) are associated with increased cardiovascular morbidity and mortality. However, the role of 1,25(OH)2D in acute kidney injury (AKI) is unclear, with very limited data. This pilot study examined the relationship between 1,25(OH)2D levels in critically ill patients with AKI and clinical outcomes. METHODS Plasma 1,25(OH)2D, intact parathyroid hormone (iPTH), 25-OH Vitamin D (VitD), calcium and phosphorus were measured in 34 patients with AKI without pre-existing chronic kidney disease and 12 healthy controls. RESULTS The mean 1,25(OH)2D levels were significantly lower in patients with AKI compared to controls, (42±5.6 pg/mL vs. 76.1±5.3 pg/mL, P <0.0001). The mortality in patients with AKI was 30%. 1,25(OH)2D levels were higher in non-survivors than survivors (62±41.4 pg/mL vs. 33.7±24.2 pg/mL respectively, P = 0.046) and serum phosphorus was also higher in non-survivors (6.2±2.1 mg/dL vs. 4.6±1.6 mg/dL, P = 0.019). However, on multivariate regression analysis, accounting for age and APACHE II score, higher levels of 1,25(OH)2D was not associated with mortality in critically ill patients with AKI. CONCLUSION Mineral metabolism is dysregulated within days of acute renal injury in critically ill patients. On univariate analysis, high levels of calcitriol were associated with adverse clinical outcome in AKI. This association was not apparent after adjusting for age and APACHE II. Large controlled studies are needed to confirm these results, and determine if higher 1,25(OH)2D mediates worse outcomes in AKI.
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Affiliation(s)
- Anitha Vijayan
- Renal Division, Washington University in St. Louis, St. Louis, MO
| | - Tingting Li
- Renal Division, Washington University in St. Louis, St. Louis, MO
| | - Adriana Dusso
- Renal Division, Washington University in St. Louis, St. Louis, MO
| | - Sanjay Jain
- Renal Division, Washington University in St. Louis, St. Louis, MO
| | - Daniel W Coyne
- Renal Division, Washington University in St. Louis, St. Louis, MO
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Ichchou L, Rist S, Lespessailles E, Prié D, Benhamou CL. Reversible increase in FGF23 in a hypophosphatemic renal and bone disease linked to antiviral therapy by adefovir. Joint Bone Spine 2013; 80:668-9. [DOI: 10.1016/j.jbspin.2013.02.014] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2012] [Accepted: 02/26/2013] [Indexed: 11/26/2022]
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Ali FN, Hassinger A, Price H, Langman CB. Preoperative plasma FGF23 levels predict acute kidney injury in children: results of a pilot study. Pediatr Nephrol 2013; 28:959-62. [PMID: 23314442 DOI: 10.1007/s00467-012-2395-2] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/15/2012] [Revised: 12/06/2012] [Accepted: 12/07/2012] [Indexed: 10/27/2022]
Abstract
BACKGROUND Acute kidney injury (AKI) carries a large burden of morbidity and mortality. Early diagnosis may lead to better strategies of clinical care. Cardiac surgery involving cardiopulmonary bypass is associated with a significant incidence of AKI. The study objective was to determine whether or not preoperative fibroblast growth factor-23 (FGF23) levels differed among pediatric patients who did or did not develop AKI following cardiac surgery. METHODS A nested case-control study was performed. FGF23 levels were measured pre- and post-operatively in 19 children without chronic kidney disease (CKD) who underwent cardiopulmonary bypass. Five patients developed AKI and 14 patients served as controls. RESULTS FGF23 levels in patients who developed AKI following cardiac surgery were elevated above normal levels, both pre-operatively and post-operatively compared with those patients who did not develop AKI. Relative risk of developing AKI when the pre-operative FGF23 level was >86 RU/mL was 2.0 (p = 0.033). Preoperative FGF23 levels correlated with post-operative fluid gain (correlation coefficient 0.607, p = 0.0059). CONCLUSIONS FGF23 may serve as a pre-operative prognostic indicator of the development of AKI following cardiopulmonary bypass surgery in pediatric patients without CKD. Identifying patients more likely to have AKI following surgery provides a means of achieving closer clinical management of AKI and fluid balance.
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Affiliation(s)
- Farah N Ali
- Kidney Diseases, Lurie Children's Hospital, 225 E Chicago Avenue, Box 37, Chicago, IL, USA.
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Chua HR, Schneider AG, Baldwin I, Collins A, Ho L, Bellomo R. Phoxilium vs Hemosol-B0 for continuous renal replacement therapy in acute kidney injury. J Crit Care 2013; 28:884.e7-14. [PMID: 23683569 DOI: 10.1016/j.jcrc.2013.02.013] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2012] [Revised: 01/12/2013] [Accepted: 02/17/2013] [Indexed: 10/26/2022]
Abstract
PURPOSE This study aimed to compare the biochemical effects of Phoxilium (containing phosphate at 1.2 mmol/L; Gambro Lundia AB, Lund, Sweden) and Hemosol-B0 (Gambro Lundia AB) as dialysate and/or replacement fluid during continuous renal replacement therapy (CRRT). METHODS We examined serum biochemistry in critically ill patients for 42 hours of Phoxilium administration for the prevention of hypophosphatemia during CRRT and compared them with corresponding results in random historical controls who received Hemosol-B0. RESULTS We studied 15 patients in each arm (Phoxilium vs Hemosol-B0). Respective median ages were 57 (49-68) and 64 (57-67) years. Baseline patient illness severity scores, prescribed CRRT effluent rates, and cumulative phosphate intakes were comparable. After 36 to 42 hours of Phoxilium administration, serum phosphate levels increased from 0.95 (0.81-1.13) to 1.44 (1.23-1.78) mmol/L, in contrast to the decline from 1.71 (1.09-2.00) to 0.83 (0.55-1.59) mmol/L with Hemosol-B0 (P=.0001). Serum ionized calcium levels decreased from 1.27 (1.22-1.37) to 1.12 (1.06-1.21) mmol/L with Phoxilium, compared with an increase from 1.09 (0.90-1.19) to 1.20 (1.16-1.25) mmol/L with Hemosol-B0 (P<.0001). Serum bicarbonate, base excess levels, and effective strong ion difference decreased with Phoxilium and were lower than those with Hemosol-B0 at 36 to 42 hours (P<.05). CONCLUSION Phoxilium effectively prevented hypophosphatemia during CRRT but was associated with relative metabolic acidosis and hypocalcemia compared with Hemosol-B0 use.
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Affiliation(s)
- Horng-Ruey Chua
- Department of Intensive Care, Austin Hospital, Melbourne, Australia; Division of Nephrology, University Medicine Cluster, National University Hospital, National University Health System, Singapore
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Plasma FGF23 levels increase rapidly after acute kidney injury. Kidney Int 2013; 84:776-85. [PMID: 23657144 PMCID: PMC3766419 DOI: 10.1038/ki.2013.150] [Citation(s) in RCA: 131] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2012] [Revised: 01/22/2013] [Accepted: 02/22/2013] [Indexed: 12/19/2022]
Abstract
Emerging evidence suggests that fibroblast growth factor 23 (FGF23) levels are elevated in patients with acute kidney injury (AKI). In order to determine how early this increase occurs we used a murine folic acid nephropathy model and found that plasma FGF23 levels increased significantly from baseline already after 1 hour of AKI, with an 18-fold increase at 24 hours. Similar elevations of FGF23 levels were found when AKI was induced in mice with osteocyte-specific parathyroid hormone receptor ablation or the global deletion of parathyroid hormone or vitamin D receptor, indicating that the increase in FGF23 was independent of parathyroid hormone and vitamin D signaling. Furthermore, FGF23 levels increased to a similar extent in wild-type mice maintained on normal or phosphate-depleted diets prior to induction of AKI, indicating that the marked FGF23 elevation is at least partially independent of dietary phosphate. Bone production of FGF23 was significantly increased in AKI. The half-life of intravenously administered recombinant FGF23 was only modestly increased. Consistent with the mouse data, plasma FGF23 levels rose 15.9-fold by 24 hours following cardiac surgery in patients who developed AKI. The levels were significantly higher than in those without postoperative AKI. Thus, circulating FGF23 levels rise rapidly during AKI in rodents and humans. In mice this increase is independent of established modulators of FGF23 secretion.
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