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Grigore TV, Zuidscherwoude M, Olauson H, Hoenderop JG. Lessons from Klotho mouse models to understand mineral homeostasis. Acta Physiol (Oxf) 2024; 240:e14220. [PMID: 39176993 DOI: 10.1111/apha.14220] [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: 05/31/2024] [Revised: 07/30/2024] [Accepted: 08/14/2024] [Indexed: 08/24/2024]
Abstract
AIM Klotho, a key component of the endocrine fibroblast growth factor receptor-fibroblast growth factor axis, is a multi-functional protein that impacts renal electrolyte handling. The physiological significance of Klotho will be highlighted in the regulation of calcium, phosphate, and potassium metabolism. METHODS In this review, we compare several murine models with different renal targeted deletions of Klotho and the insights into the molecular and physiological function that these models offer. RESULTS In vivo, Klotho deficiency is associated with severely impaired mineral metabolism, with consequences on growth, longevity and disease development. Additionally, we explore the perspectives of Klotho in renal pathology and vascular events, as well as potential Klotho treatment options. CONCLUSION This comprehensive review emphasizes the use of Klotho to shed light on deciphering the renal molecular in vivo mechanisms in electrolyte handling, as well as novel therapeutic interventions.
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Affiliation(s)
- Teodora V Grigore
- Department of Medical BioSciences, Radboud Research Institute for Medical Innovation, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Malou Zuidscherwoude
- Department of Medical BioSciences, Radboud Research Institute for Medical Innovation, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Hannes Olauson
- Division of Pathology, Department of Laboratory Medicine, Karolinska Institutet, Stockholm, Sweden
| | - Joost G Hoenderop
- Department of Medical BioSciences, Radboud Research Institute for Medical Innovation, Radboud University Medical Center, Nijmegen, The Netherlands
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2
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Wan Abdul Azim WA, Kassim NK, Taib H, Abdullah NH, Che Abdul Aziz NA, Ibrahim HA. The Effect of Periodontitis on Fibroblast Growth Factor 23 Levels in Predialysis Chronic Kidney Disease Patients. Cureus 2024; 16:e65166. [PMID: 39176315 PMCID: PMC11339633 DOI: 10.7759/cureus.65166] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/22/2024] [Indexed: 08/24/2024] Open
Abstract
Introduction Chronic kidney disease (CKD) is known to cause an increase in fibroblast growth factor 23 (FGF23). Periodontitis, a condition recognized as a risk factor for CKD, is also potentially associated with the increment of FGF23. This study aims to compare FGF23 levels in CKD patients with and without periodontitis and non-CKD patients with and without periodontitis. Correlation with serum phosphate, calcium, and intact parathyroid hormone (iPTH) was assessed. Additionally, associations between FGF23, calcium, phosphate, iPTH, creatinine, urea, plaque score, and bleeding score with periodontitis in CKD patients were determined. Method A total of 124 participants were categorized into four groups: CKD patients with periodontitis (n=31), CKD patients without periodontitis (n=32), periodontitis patients without CKD (n=32), and healthy population (n=29). The selected CKD patients include those from stages 3 and 4 (predialysis) patients. Serum levels of FGF23, calcium, phosphate, iPTH, creatinine, and urea were analyzed. Oral examinations were conducted to determine the presence and absence of periodontitis and assess plaque and bleeding scores. Result A significantly higher level of FGF23 was found in CKD compared to non-CKD groups; however, no difference was observed with the presence of periodontitis in both CKD and non-CKD. There was no significant correlation found between FGF23 and serum calcium, phosphate, or iPTH concerning periodontal status. Apart from the bleeding score, there was no association between FGF23, calcium, phosphate, iPTH, creatinine, urea, and plaque score with the presence of periodontitis in CKD patients. Conclusion The presence of periodontitis was not associated with higher FGF23 levels in CKD patients. Changes in FGF23, calcium, phosphate, iPTH, creatinine, urea, and plaque score could not be attributed to the presence of periodontitis in CKD patients.
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Affiliation(s)
- Wan Asma Wan Abdul Azim
- Department of Chemical Pathology, Universiti Sains Malaysia School of Medical Sciences, Kubang Kerian, MYS
| | | | - Haslina Taib
- Unit of Periodontics, School of Dental Sciences, Universiti Sains Malaysia, Kubang Kerian, MYS
| | - Nurul Huda Abdullah
- Department of Internal Medicine, Universiti Sains Malaysia School of Medical Sciences, Kubang Kerian, MYS
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Saaoud F, Lu Y, Xu K, Shao Y, Praticò D, Vazquez-Padron RI, Wang H, Yang X. Protein-rich foods, sea foods, and gut microbiota amplify immune responses in chronic diseases and cancers - Targeting PERK as a novel therapeutic strategy for chronic inflammatory diseases, neurodegenerative disorders, and cancer. Pharmacol Ther 2024; 255:108604. [PMID: 38360205 PMCID: PMC10917129 DOI: 10.1016/j.pharmthera.2024.108604] [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: 11/09/2023] [Revised: 01/05/2024] [Accepted: 01/29/2024] [Indexed: 02/17/2024]
Abstract
The endoplasmic reticulum (ER) is a cellular organelle that is physiologically responsible for protein folding, calcium homeostasis, and lipid biosynthesis. Pathological stimuli such as oxidative stress, ischemia, disruptions in calcium homeostasis, and increased production of normal and/or folding-defective proteins all contribute to the accumulation of misfolded proteins in the ER, causing ER stress. The adaptive response to ER stress is the activation of unfolded protein response (UPR), which affect a wide variety of cellular functions to maintain ER homeostasis or lead to apoptosis. Three different ER transmembrane sensors, including PKR-like ER kinase (PERK), activating transcription factor 6 (ATF6), and inositol-requiring enzyme-1 (IRE1), are responsible for initiating UPR. The UPR involves a variety of signal transduction pathways that reduce unfolded protein accumulation by boosting ER-resident chaperones, limiting protein translation, and accelerating unfolded protein degradation. ER is now acknowledged as a critical organelle in sensing dangers and determining cell life and death. On the other hand, UPR plays a critical role in the development and progression of several diseases such as cardiovascular diseases (CVD), metabolic disorders, chronic kidney diseases, neurological disorders, and cancer. Here, we critically analyze the most current knowledge of the master regulatory roles of ER stress particularly the PERK pathway as a conditional danger receptor, an organelle crosstalk regulator, and a regulator of protein translation. We highlighted that PERK is not only ER stress regulator by sensing UPR and ER stress but also a frontier sensor and direct senses for gut microbiota-generated metabolites. Our work also further highlighted the function of PERK as a central hub that leads to metabolic reprogramming and epigenetic modification which further enhanced inflammatory response and promoted trained immunity. Moreover, we highlighted the contribution of ER stress and PERK in the pathogenesis of several diseases such as cancer, CVD, kidney diseases, and neurodegenerative disorders. Finally, we discuss the therapeutic target of ER stress and PERK for cancer treatment and the potential novel therapeutic targets for CVD, metabolic disorders, and neurodegenerative disorders. Inhibition of ER stress, by the development of small molecules that target the PERK and UPR, represents a promising therapeutic strategy.
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Affiliation(s)
- Fatma Saaoud
- Lemole Center for Integrated Lymphatics and Vascular Research, Department of Cardiovascular Sciences, Temple University Lewis Katz School of Medicine, Philadelphia, PA, USA
| | - Yifan Lu
- Lemole Center for Integrated Lymphatics and Vascular Research, Department of Cardiovascular Sciences, Temple University Lewis Katz School of Medicine, Philadelphia, PA, USA
| | - Keman Xu
- Lemole Center for Integrated Lymphatics and Vascular Research, Department of Cardiovascular Sciences, Temple University Lewis Katz School of Medicine, Philadelphia, PA, USA
| | - Ying Shao
- Lemole Center for Integrated Lymphatics and Vascular Research, Department of Cardiovascular Sciences, Temple University Lewis Katz School of Medicine, Philadelphia, PA, USA
| | - Domenico Praticò
- Alzheimer's Center, Temple University Lewis Katz School of Medicine, Philadelphia, PA, USA
| | | | - Hong Wang
- Metabolic Disease Research, Department of Cardiovascular Sciences, Temple University Lewis Katz School of Medicine, Philadelphia, PA, USA
| | - Xiaofeng Yang
- Lemole Center for Integrated Lymphatics and Vascular Research, Department of Cardiovascular Sciences, Temple University Lewis Katz School of Medicine, Philadelphia, PA, USA; Metabolic Disease Research, Department of Cardiovascular Sciences, Temple University Lewis Katz School of Medicine, Philadelphia, PA, USA.
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4
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Martín-Vírgala J, Martín-Carro B, Fernández-Villabrille S, Ruiz-Torres MP, Gómez-Alonso C, Rodríguez-García M, Fernández-Martín JL, Alonso-Montes C, Panizo S, Cannata-Andía JB, Naves-Díaz M, Carrillo-López N. Soluble Klotho, a Potential Biomarker of Chronic Kidney Disease-Mineral Bone Disorders Involved in Healthy Ageing: Lights and Shadows. Int J Mol Sci 2024; 25:1843. [PMID: 38339121 PMCID: PMC10855561 DOI: 10.3390/ijms25031843] [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: 12/28/2023] [Revised: 01/23/2024] [Accepted: 01/31/2024] [Indexed: 02/12/2024] Open
Abstract
Shortly after the discovery of Klotho, interest grew in its potential role in chronic kidney disease (CKD). There are three isoforms of the Klotho protein: αKlotho, βKlotho and γKlotho. This review will focus on αKlotho due to its relevance as a biomarker in CKD. αKlotho is synthesized mainly in the kidneys, but it can be released into the bloodstream and urine as soluble Klotho (sKlotho), which undertakes systemic actions, independently or in combination with FGF23. It is usually accepted that sKlotho levels are reduced early in CKD and that lower levels of sKlotho might be associated with the main chronic kidney disease-mineral bone disorders (CKD-MBDs): cardiovascular and bone disease. However, as results are inconsistent, the applicability of sKlotho as a CKD-MBD biomarker is still a matter of controversy. Much of the inconsistency can be explained due to low sample numbers, the low quality of clinical studies, the lack of standardized assays to assess sKlotho and a lack of consensus on sample processing, especially in urine. In recent decades, because of our longer life expectancies, the prevalence of accelerated-ageing diseases, such as CKD, has increased. Exercise, social interaction and caloric restriction are considered key factors for healthy ageing. While exercise and social interaction seem to be related to higher serum sKlotho levels, it is not clear whether serum sKlotho might be influenced by caloric restriction. This review focuses on the possible role of sKlotho as a biomarker in CKD-MBD, highlighting the difference between solid knowledge and areas requiring further research, including the role of sKlotho in healthy ageing.
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Affiliation(s)
- Julia Martín-Vírgala
- Metabolismo Óseo, Vascular y Enfermedades Inflamatorias Crónicas, Instituto de Investigación Sanitaria del Principado de Asturias (ISPA), 33011 Oviedo, Spain
- Redes de Investigación Cooperativa Orientadas a Resultados en Salud (RICORS2040, Kidney Disease), 28040 Madrid, Spain;
| | - Beatriz Martín-Carro
- Metabolismo Óseo, Vascular y Enfermedades Inflamatorias Crónicas, Instituto de Investigación Sanitaria del Principado de Asturias (ISPA), 33011 Oviedo, Spain
- Redes de Investigación Cooperativa Orientadas a Resultados en Salud (RICORS2040, Kidney Disease), 28040 Madrid, Spain;
| | - Sara Fernández-Villabrille
- Metabolismo Óseo, Vascular y Enfermedades Inflamatorias Crónicas, Instituto de Investigación Sanitaria del Principado de Asturias (ISPA), 33011 Oviedo, Spain
- Redes de Investigación Cooperativa Orientadas a Resultados en Salud (RICORS2040, Kidney Disease), 28040 Madrid, Spain;
| | - María Piedad Ruiz-Torres
- Redes de Investigación Cooperativa Orientadas a Resultados en Salud (RICORS2040, Kidney Disease), 28040 Madrid, Spain;
- Área 5—Fisiología y Fisiopatología Renal y Vascular del Instituto Ramón y Cajal de Investigación Sanitaria (IRYCIS), Physiology Unit, Department of Systems Biology, Facultad de Medicina y Ciencias de la Salud, Universidad de Alcalá, 28871 Alcalá de Henares, Spain
| | - Carlos Gómez-Alonso
- Metabolismo Óseo, Vascular y Enfermedades Inflamatorias Crónicas, Instituto de Investigación Sanitaria del Principado de Asturias (ISPA), 33011 Oviedo, Spain
- Bone and Mineral Research Unit, Hospital Universitario Central de Asturias, 33011 Oviedo, Spain
| | - Minerva Rodríguez-García
- Metabolismo Óseo, Vascular y Enfermedades Inflamatorias Crónicas, Instituto de Investigación Sanitaria del Principado de Asturias (ISPA), 33011 Oviedo, Spain
- Redes de Investigación Cooperativa Orientadas a Resultados en Salud (RICORS2040, Kidney Disease), 28040 Madrid, Spain;
- Nephrology Unit, Hospital Universitario Central de Asturias, 33011 Oviedo, Spain
| | - José Luis Fernández-Martín
- Metabolismo Óseo, Vascular y Enfermedades Inflamatorias Crónicas, Instituto de Investigación Sanitaria del Principado de Asturias (ISPA), 33011 Oviedo, Spain
- Redes de Investigación Cooperativa Orientadas a Resultados en Salud (RICORS2040, Kidney Disease), 28040 Madrid, Spain;
- Bone and Mineral Research Unit, Hospital Universitario Central de Asturias, 33011 Oviedo, Spain
| | - Cristina Alonso-Montes
- Metabolismo Óseo, Vascular y Enfermedades Inflamatorias Crónicas, Instituto de Investigación Sanitaria del Principado de Asturias (ISPA), 33011 Oviedo, Spain
- Redes de Investigación Cooperativa Orientadas a Resultados en Salud (RICORS2040, Kidney Disease), 28040 Madrid, Spain;
| | - Sara Panizo
- Metabolismo Óseo, Vascular y Enfermedades Inflamatorias Crónicas, Instituto de Investigación Sanitaria del Principado de Asturias (ISPA), 33011 Oviedo, Spain
- Redes de Investigación Cooperativa Orientadas a Resultados en Salud (RICORS2040, Kidney Disease), 28040 Madrid, Spain;
| | - Jorge B. Cannata-Andía
- Redes de Investigación Cooperativa Orientadas a Resultados en Salud (RICORS2040, Kidney Disease), 28040 Madrid, Spain;
- Department of Medicine, Universidad de Oviedo, 33011 Oviedo, Spain
| | - Manuel Naves-Díaz
- Metabolismo Óseo, Vascular y Enfermedades Inflamatorias Crónicas, Instituto de Investigación Sanitaria del Principado de Asturias (ISPA), 33011 Oviedo, Spain
- Redes de Investigación Cooperativa Orientadas a Resultados en Salud (RICORS2040, Kidney Disease), 28040 Madrid, Spain;
- Bone and Mineral Research Unit, Hospital Universitario Central de Asturias, 33011 Oviedo, Spain
| | - Natalia Carrillo-López
- Metabolismo Óseo, Vascular y Enfermedades Inflamatorias Crónicas, Instituto de Investigación Sanitaria del Principado de Asturias (ISPA), 33011 Oviedo, Spain
- Redes de Investigación Cooperativa Orientadas a Resultados en Salud (RICORS2040, Kidney Disease), 28040 Madrid, Spain;
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5
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Lee JC, Hsieh TH, Kao YC, Tsai CF, Huang HY, Shih CY, Song HL, Oda Y, Chih-Hsueh Chen P, Pan CC, Sittampalam K, Petersson F, Konishi E, Chiu WY, Chen CF, Carpenter TO, Lu TP, Chang CD, Huang SC, Folpe AL. Klotho Overexpression Is Frequently Associated With Upstream Rearrangements in Fusion-Negative Phosphaturic Mesenchymal Tumors of Bone and Sinonasal Tract. Mod Pathol 2023; 36:100336. [PMID: 37742927 DOI: 10.1016/j.modpat.2023.100336] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2023] [Revised: 08/31/2023] [Accepted: 09/15/2023] [Indexed: 09/26/2023]
Abstract
Phosphaturic mesenchymal tumors (PMT) are uncommon neoplasms that cause hypophosphatemia/osteomalacia mainly by secreting fibroblast growth factor 23. We previously identified FN1::FGFR1/FGF1 fusions in nearly half of the PMTs and frequent KL (Klotho or α-Klotho) overexpression in only those with no known fusion. Here, we studied a larger cohort of PMTs for KL expression and alterations. By FN1 break-apart fluorescence in situ hybridization (FISH) and reappraisal of previous RNA sequencing data, 6 tumors previously considered "fusion-negative" (defined by negative results of FISH for FN1::FGFR1 fusion and FGF1 break-apart and/or of RNA sequencing) were reclassified as fusion-positive PMTs, including 1 containing a novel FN1::ZACN fusion. The final cohort of fusion-negative PMTs included 33 tumors from 32 patients, which occurred in the bone (n = 18), soft tissue (n = 10), sinonasal tract (n = 4), and brain (n = 1). In combination with previous work, RNA sequencing, RNA in situ hybridization, and immunohistochemistry showed largely concordant results and demonstrated KL/α-Klotho overexpression in 17 of the 28 fusion-negative and none of the 10 fusion-positive PMTs studied. Prompted by a patient in this cohort harboring germline KL upstream translocation with systemic α-Klotho overexpression and multifocal PMTs, FISH was performed and revealed KL rearrangement in 16 of the 33 fusion-negative PMTs (one also with amplification), including 14 of the 17 cases with KL/α-Klotho overexpression and none of the 11 KL/α-Klotho-low fusion-negative and 11 fusion-positive cases studied. Whole genomic sequencing confirmed translocation and inversion in 2 FISH-positive cases involving the KL upstream region, warranting further investigation into the mechanism whereby these rearrangements may lead to KL upregulation. Methylated DNA immunoprecipitation and sequencing suggested no major role of promoter methylation in KL regulation in PMT. Interestingly, KL-high/-rearranged cases seemed to form a clinicopathologically homogeneous group, showing a predilection for skeletal/sinonasal locations and typically matrix-poor, cellular solitary fibrous tumor-like morphology. Importantly, FGFR1 signaling pathways were upregulated in fusion-negative PMTs regardless of the KL status compared with non-PMT mesenchymal tumors by gene set enrichment analysis, perhaps justifying FGFR1 inhibition in treating this subset of PMTs.
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Affiliation(s)
- Jen-Chieh Lee
- Department and Graduate Institute of Pathology, National Taiwan University Hospital, National Taiwan University College of Medicine, Taipei, Taiwan.
| | - Tsung-Han Hsieh
- Joint Biobank, Office of Human Research, Taipei Medical University, Taipei, Taiwan
| | - Yu-Chien Kao
- Department of Pathology, Taipei Medical University Hospital and School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan; Department of Pathology, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Cheng-Fong Tsai
- Department of Medical Research, National Taiwan University Hospital, Taipei, Taiwan
| | - Hsuan-Ying Huang
- Department of Anatomical Pathology, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung, Taiwan
| | - Ching-Yu Shih
- Institute of Health Data Analytics and Statistics, College of Public Health, National Taiwan University, Taipei, Taiwan
| | - Hsiang-Lin Song
- Department of Pathology, National Taiwan University Hospital Hsin-Chu Branch, Zhubei City, Taiwan
| | - Yoshinao Oda
- Department of Anatomic Pathology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
| | - Paul Chih-Hsueh Chen
- Department of Pathology, National Yang Ming University and Taipei Veterans General Hospital, Taipei, Taiwan
| | - Chin-Chen Pan
- Department of Pathology, National Yang Ming University and Taipei Veterans General Hospital, Taipei, Taiwan
| | | | - Fredrik Petersson
- Department of Pathology, National University Health System, Singapore, Singapore
| | - Eiichi Konishi
- Department of Pathology, Kyoto Prefectural University of Medicine, Kyoto, Japan
| | - Wei-Yih Chiu
- Division of Metabolism and Endocrinology, Department of Internal Medicine, National Taiwan University Hospital, Taipei, Taiwan
| | - Cheng-Fong Chen
- Department of Orthopedics, Taipei Veterans General Hospital, Taipei, Taiwan
| | - Thomas O Carpenter
- Department of Pediatrics (Endocrinology), Yale University School of Medicine, New Haven, Connecticut
| | - Tzu-Pin Lu
- Institute of Health Data Analytics and Statistics, College of Public Health, National Taiwan University, Taipei, Taiwan
| | - Ching-Di Chang
- Department of Radiology, Kaohsiung Chang Gung Memorial Hospital, Kaohsiung, Taiwan
| | - Shih-Chiang Huang
- Department of Anatomic Pathology, Linkou Chang Gung Memorial Hospital, Chang Gung University, College of Medicine, Taoyuan, Taiwan; Graduate Institute of Clinical Medical Sciences, College of Medicine, Chang Gung University, Taoyuan, Taiwan
| | - Andrew L Folpe
- Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, Minnesota
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Hobson S, Arefin S, Witasp A, Hernandez L, Kublickiene K, Shiels PG, Stenvinkel P. Accelerated Vascular Aging in Chronic Kidney Disease: The Potential for Novel Therapies. Circ Res 2023; 132:950-969. [PMID: 37053277 DOI: 10.1161/circresaha.122.321751] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 04/15/2023]
Abstract
The pathophysiology of vascular disease is linked to accelerated biological aging and a combination of genetic, lifestyle, biological, and environmental risk factors. Within the scenario of uncontrolled artery wall aging processes, CKD (chronic kidney disease) stands out as a valid model for detailed structural, functional, and molecular studies of this process. The cardiorenal syndrome relates to the detrimental bidirectional interplay between the kidney and the cardiovascular system. In addition to established risk factors, this group of patients is subjected to a plethora of other emerging vascular risk factors, such as inflammation, oxidative stress, mitochondrial dysfunction, vitamin K deficiency, cellular senescence, somatic mutations, epigenetic modifications, and increased apoptosis. A better understanding of the molecular mechanisms through which the uremic milieu triggers and maintains early vascular aging processes, has provided important new clues on inflammatory pathways and emerging risk factors alike, and to the altered behavior of cells in the arterial wall. Advances in the understanding of the biology of uremic early vascular aging opens avenues to novel pharmacological and nutritional therapeutic interventions. Such strategies hold promise to improve future prevention and treatment of early vascular aging not only in CKD but also in the elderly general population.
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Affiliation(s)
- S Hobson
- Division of Renal Medicine, Department of Clinical Science, Intervention and Technology, Karolinska Institutet, Stockholm, Sweden (S.H., S.A., A.W., L.H., K.K., P.S.)
| | - S Arefin
- Division of Renal Medicine, Department of Clinical Science, Intervention and Technology, Karolinska Institutet, Stockholm, Sweden (S.H., S.A., A.W., L.H., K.K., P.S.)
| | - A Witasp
- Division of Renal Medicine, Department of Clinical Science, Intervention and Technology, Karolinska Institutet, Stockholm, Sweden (S.H., S.A., A.W., L.H., K.K., P.S.)
| | - L Hernandez
- Division of Renal Medicine, Department of Clinical Science, Intervention and Technology, Karolinska Institutet, Stockholm, Sweden (S.H., S.A., A.W., L.H., K.K., P.S.)
| | - K Kublickiene
- Division of Renal Medicine, Department of Clinical Science, Intervention and Technology, Karolinska Institutet, Stockholm, Sweden (S.H., S.A., A.W., L.H., K.K., P.S.)
| | - P G Shiels
- School of Molecular Biosciences, MVLS, University of Glasgow, United Kingdom (P.G.S.)
| | - P Stenvinkel
- Division of Renal Medicine, Department of Clinical Science, Intervention and Technology, Karolinska Institutet, Stockholm, Sweden (S.H., S.A., A.W., L.H., K.K., P.S.)
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7
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Heijboer AC, Cavalier E. The Measurement and Interpretation of Fibroblast Growth Factor 23 (FGF23) Concentrations. Calcif Tissue Int 2023; 112:258-270. [PMID: 35665817 PMCID: PMC9859838 DOI: 10.1007/s00223-022-00987-9] [Citation(s) in RCA: 20] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/17/2022] [Accepted: 05/06/2022] [Indexed: 02/05/2023]
Abstract
Two decades after the discovery of the hormone FGF23, we know more about phosphate homeostasis as it turned out that FGF23 is the central hormone that regulates this. Hereditary hypophosphatemic rickets and tumor-induced osteomalacia could by then be explained, by autonomous FGF23 production, and the nephrology field was excited by this new marker as it turned out to be independently associated with mortality in people treated by hemodialysis. This led to the development of several immunoassays to be able to measure FGF23 in blood. In the past years we learned that FGF23 is a rather stable peptide, the precision of the assays is acceptable but assays are not standardized and therefore not comparable. This means that reference values and cutoff values need to be assay specific. For several assays reference values have been established and gender and age did not seem of high importance. The phosphate content of the diet, which can be culturally dependent, however, should be taken into account when interpreting results, but to what extent is not totally clear. Currently, clinical application of the immunoassays is established in the diagnosis of hereditary hypophosphatemic rickets and diagnosis and follow-up of tumor-induced osteomalacia. Definite conclusions on the usefulness of the FGF23 measurement in people with CKD either as a marker for risk prediction or a as target for treatment remains to be determined. The latter applications would require dedicated prospective clinical trials, which may take years, before providing answers. To improve the standardization of the FGF23 assays and to shed light on the biological functions that fragments might have we might aim for an LC-MS/MS-based method to quantify both intact and fragmented FGF23. In this literature review we will summarize the current knowledge on the physiological role of FGF23, its quantification, and the clinical usefulness of its determination.
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Affiliation(s)
- Annemieke C Heijboer
- Endocrine Laboratory, Department of Clinical Chemistry, Amsterdam Gastroenterology Endocrinology & Metabolism, Amsterdam UMC, Vrije Universiteit Amsterdam and University of Amsterdam, de Boelelaan 1117 and Meibergdreef 9, Amsterdam, The Netherlands.
| | - Etienne Cavalier
- Department of Clinical Chemistry, CHU de Liège, University of Liège, 4000, Liège, Belgium
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Zhou W, Chen MM, Liu HL, Si ZL, Wu WH, Jiang H, Wang LX, Vaziri ND, An XF, Su K, Chen C, Tan NH, Zhang ZH. Dihydroartemisinin suppresses renal fibrosis in mice by inhibiting DNA-methyltransferase 1 and increasing Klotho. Acta Pharmacol Sin 2022; 43:2609-2623. [PMID: 35347248 PMCID: PMC9525601 DOI: 10.1038/s41401-022-00898-3] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2021] [Accepted: 03/06/2022] [Indexed: 02/07/2023] Open
Abstract
Renal fibrosis is an unavoidable end result of all forms of progressive chronic kidney diseases (CKD). Discovery of efficacious drugs against renal fibrosis is in crucial need. In a preliminary study we found that a derivative of artemisinin, dihydroartemisinin (DHA), exerted strong renoprotection, and reversed renal fibrosis in adenine-induced CKD mouse model. In this study we investigated the anti-fibrotic mechanisms of DHA, particularly its specific target in renal cells. Renal fibrosis was induced in mice by unilateral ureteral obstruction (UUO) or oral administration of adenine (80 mg · kg-1), the mice received DHA (30 mg · kg-1 · d-1, i.g.) for 14 or 21 days, respectively. We showed that DHA administration markedly attenuated the inflammation and fibrotic responses in the kidneys and significantly improved the renal function in both the renal fibrosis mouse models. In adenine-treated mice, DHA was more effective than 5-azacytidine against renal fibrosis. The anti-fibrotic effects of DHA were also observed in TGF-β1-treated HK-2 cells. In order to determine the target protein of DHA, we conducted pull-down technology coupled with shotgun proteomics using a small-molecule probe based on the structure of DHA (biotin-DHA). As a results, DNA methyltransferase 1 (DNMT1) was identified as the anti-fibrotic target of DHA in 3 different types of renal cell lines (HK-2, HEK293 and 3T3). We demonstrated that DHA directly bound to Asn 1529 and Thr 1528 of DNMT1 with a Kd value of 8.18 μM. In primary mouse renal tubular cells, we showed that DHA (10 μM) promoted DNMT1 degradation via the ubiquitin-proteasome pathway. DHA-reduced DNMT1 expression effectively reversed Klotho promoter hypermethylation, which led to the reversal of Klotho protein loss in the kidney of UUO mice. This subsequently resulted in inhibition of the Wnt/β-catenin and TGF-β/Smad signaling pathways and consequently conferred renoprotection in the animals. Knockdown of Klotho abolished the renoprotective effect of DHA in UUO mice. Our study reveals a novel pharmacological activity for DHA, i.e., renoprotection. DHA exhibits this effect by targeting DNMT1 to reverse Klotho repression. This study provides an evidence for the possible clinical application of DHA in the treatment of renal fibrosis.
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Affiliation(s)
- Wei Zhou
- State Key Laboratory of Natural Medicines, Department of TCMs Pharmaceuticals, School of Traditional Chinese Pharmacy, China Pharmaceutical University, Nanjing, 210009, China
| | - Min-Min Chen
- State Key Laboratory of Natural Medicines, Department of TCMs Pharmaceuticals, School of Traditional Chinese Pharmacy, China Pharmaceutical University, Nanjing, 210009, China
| | - Hui-Ling Liu
- State Key Laboratory of Natural Medicines, Department of TCMs Pharmaceuticals, School of Traditional Chinese Pharmacy, China Pharmaceutical University, Nanjing, 210009, China
| | - Zi-Lin Si
- State Key Laboratory of Natural Medicines, Department of TCMs Pharmaceuticals, School of Traditional Chinese Pharmacy, China Pharmaceutical University, Nanjing, 210009, China
| | - Wen-Hui Wu
- State Key Laboratory of Natural Medicines, Department of TCMs Pharmaceuticals, School of Traditional Chinese Pharmacy, China Pharmaceutical University, Nanjing, 210009, China
| | - Hong Jiang
- State Key Laboratory of Natural Medicines, Department of TCMs Pharmaceuticals, School of Traditional Chinese Pharmacy, China Pharmaceutical University, Nanjing, 210009, China
| | - Lin-Xiao Wang
- State Key Laboratory of Natural Medicines, Department of TCMs Pharmaceuticals, School of Traditional Chinese Pharmacy, China Pharmaceutical University, Nanjing, 210009, China
| | - Nosratola D Vaziri
- Division of Nephrology and Hypertension, School of Medicine, University of California Irvine, Irvine, CA, USA
| | - Xiao-Fei An
- Affiliated Hospital of Nanjing University of Chinese Medicine, Nanjing, 210023, China
| | - Ke Su
- Department of Nephrology, Renmin Hospital of Wuhan University, Wuhan, 430060, China
| | - Cheng Chen
- Department of Nephrology, Renmin Hospital of Wuhan University, Wuhan, 430060, China
| | - Ning-Hua Tan
- State Key Laboratory of Natural Medicines, Department of TCMs Pharmaceuticals, School of Traditional Chinese Pharmacy, China Pharmaceutical University, Nanjing, 210009, China.
| | - Zhi-Hao Zhang
- State Key Laboratory of Natural Medicines, Department of TCMs Pharmaceuticals, School of Traditional Chinese Pharmacy, China Pharmaceutical University, Nanjing, 210009, China.
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9
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Portales-Castillo I, Simic P. PTH, FGF-23, Klotho and Vitamin D as regulators of calcium and phosphorus: Genetics, epigenetics and beyond. Front Endocrinol (Lausanne) 2022; 13:992666. [PMID: 36246903 PMCID: PMC9558279 DOI: 10.3389/fendo.2022.992666] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/12/2022] [Accepted: 09/12/2022] [Indexed: 11/30/2022] Open
Abstract
The actions of several bone-mineral ion regulators, namely PTH, FGF23, Klotho and 1,25(OH)2 vitamin D (1,25(OH)2D), control calcium and phosphate metabolism, and each of these molecules has additional biological effects related to cell signaling, metabolism and ultimately survival. Therefore, these factors are tightly regulated at various levels - genetic, epigenetic, protein secretion and cleavage. We review the main determinants of mineral homeostasis including well-established genetic and post-translational regulators and bring attention to the epigenetic mechanisms that affect the function of PTH, FGF23/Klotho and 1,25(OH)2D. Clinically relevant epigenetic mechanisms include methylation of cytosine at CpG-rich islands, histone deacetylation and micro-RNA interference. For example, sporadic pseudohypoparathyroidism type 1B (PHP1B), a disease characterized by resistance to PTH actions due to blunted intracellular cAMP signaling at the PTH/PTHrP receptor, is associated with abnormal methylation at the GNAS locus, thereby leading to reduced expression of the stimulatory G protein α-subunit (Gsα). Post-translational regulation is critical for the function of FGF-23 and such modifications include glycosylation and phosphorylation, which regulate the cleavage of FGF-23 and hence the proportion of available FGF-23 that is biologically active. While there is extensive data on how 1,25(OH)2D and the vitamin D receptor (VDR) regulate other genes, much more needs to be learned about their regulation. Reduced VDR expression or VDR mutations are the cause of rickets and are thought to contribute to different disorders. Epigenetic changes, such as increased methylation of the VDR resulting in decreased expression are associated with several cancers and infections. Genetic and epigenetic determinants play crucial roles in the function of mineral factors and their disorders lead to different diseases related to bone and beyond.
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Affiliation(s)
- Ignacio Portales-Castillo
- Department of Medicine, Division of Nephrology, Massachusetts General Hospital and Harvard Medical School, Boston, MA, United States
- Endocrine Unit, Massachusetts General Hospital and Harvard Medical School, Boston, MA, United States
| | - Petra Simic
- Department of Medicine, Division of Nephrology, Massachusetts General Hospital and Harvard Medical School, Boston, MA, United States
- Endocrine Unit, Massachusetts General Hospital and Harvard Medical School, Boston, MA, United States
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10
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Matías-García PR, Ward-Caviness CK, Raffield LM, Gao X, Zhang Y, Wilson R, Gào X, Nano J, Bostom A, Colicino E, Correa A, Coull B, Eaton C, Hou L, Just AC, Kunze S, Lange L, Lange E, Lin X, Liu S, Nwanaji-Enwerem JC, Reiner A, Shen J, Schöttker B, Vokonas P, Zheng Y, Young B, Schwartz J, Horvath S, Lu A, Whitsel EA, Koenig W, Adamski J, Winkelmann J, Brenner H, Baccarelli AA, Gieger C, Peters A, Franceschini N, Waldenberger M. DNAm-based signatures of accelerated aging and mortality in blood are associated with low renal function. Clin Epigenetics 2021; 13:121. [PMID: 34078457 PMCID: PMC8170969 DOI: 10.1186/s13148-021-01082-w] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2020] [Accepted: 04/18/2021] [Indexed: 01/30/2023] Open
Abstract
BACKGROUND The difference between an individual's chronological and DNA methylation predicted age (DNAmAge), termed DNAmAge acceleration (DNAmAA), can capture life-long environmental exposures and age-related physiological changes reflected in methylation status. Several studies have linked DNAmAA to morbidity and mortality, yet its relationship with kidney function has not been assessed. We evaluated the associations between seven DNAm aging and lifespan predictors (as well as GrimAge components) and five kidney traits (estimated glomerular filtration rate [eGFR], urine albumin-to-creatinine ratio [uACR], serum urate, microalbuminuria and chronic kidney disease [CKD]) in up to 9688 European, African American and Hispanic/Latino individuals from seven population-based studies. RESULTS We identified 23 significant associations in our large trans-ethnic meta-analysis (p < 1.43E-03 and consistent direction of effect across studies). Age acceleration measured by the Extrinsic and PhenoAge estimators, as well as Zhang's 10-CpG epigenetic mortality risk score (MRS), were associated with all parameters of poor kidney health (lower eGFR, prevalent CKD, higher uACR, microalbuminuria and higher serum urate). Six of these associations were independently observed in European and African American populations. MRS in particular was consistently associated with eGFR (β = - 0.12, 95% CI = [- 0.16, - 0.08] change in log-transformed eGFR per unit increase in MRS, p = 4.39E-08), prevalent CKD (odds ratio (OR) = 1.78 [1.47, 2.16], p = 2.71E-09) and higher serum urate levels (β = 0.12 [0.07, 0.16], p = 2.08E-06). The "first-generation" clocks (Hannum, Horvath) and GrimAge showed different patterns of association with the kidney traits. Three of the DNAm-estimated components of GrimAge, namely adrenomedullin, plasminogen-activation inhibition 1 and pack years, were positively associated with higher uACR, serum urate and microalbuminuria. CONCLUSION DNAmAge acceleration and DNAm mortality predictors estimated in whole blood were associated with multiple kidney traits, including eGFR and CKD, in this multi-ethnic study. Epigenetic biomarkers which reflect the systemic effects of age-related mechanisms such as immunosenescence, inflammaging and oxidative stress may have important mechanistic or prognostic roles in kidney disease. Our study highlights new findings linking kidney disease to biological aging, and opportunities warranting future investigation into DNA methylation biomarkers for prognostic or risk stratification in kidney disease.
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Affiliation(s)
- Pamela R Matías-García
- TUM School of Medicine, Technical University of Munich, Munich, Germany.
- Research Unit Molecular Epidemiology, Institute of Epidemiology, Helmholtz Zentrum München, German Research Center for Environmental Health, Munich/Neuherberg, Germany.
- Institute of Epidemiology, Helmholtz Zentrum München, German Research Center for Environmental Health, Munich/Neuherberg, Germany.
- German Center for Cardiovascular Research (DZHK), Partner Site Munich Heart Alliance, Munich, Germany.
| | - Cavin K Ward-Caviness
- Center for Public Health and Environmental Assessment, US Environmental Protection Agency, Chapel Hill, NC, USA
| | - Laura M Raffield
- Department of Genetics, University of North Carolina, Chapel Hill, NC, USA
| | - Xu Gao
- Laboratory of Precision Environmental Health, Mailman School of Public Health, Columbia University, New York, NY, USA
| | - Yan Zhang
- Division of Clinical Epidemiology and Aging Research, German Cancer Research Center (DKFZ), Heidelberg, Germany
- German Cancer Consortium (DKTK), German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Rory Wilson
- Research Unit Molecular Epidemiology, Institute of Epidemiology, Helmholtz Zentrum München, German Research Center for Environmental Health, Munich/Neuherberg, Germany
- Institute of Epidemiology, Helmholtz Zentrum München, German Research Center for Environmental Health, Munich/Neuherberg, Germany
| | - Xīn Gào
- Division of Clinical Epidemiology and Aging Research, German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Jana Nano
- Institute of Epidemiology, Helmholtz Zentrum München, German Research Center for Environmental Health, Munich/Neuherberg, Germany
- German Center for Diabetes Research (DZD), Neuherberg, Germany
| | - Andrew Bostom
- Center For Primary Care and Prevention, Memorial Hospital of Rhode Island, Pawtucket, RI, USA
| | - Elena Colicino
- Department of Environmental Medicine and Public Health, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Adolfo Correa
- Departments of Medicine and Pediatrics, University of Mississippi Medical Center, Jackson, MS, USA
| | - Brent Coull
- Department of Biostatistics, Harvard T.H. Chan School of Public Health, Boston, MA, USA
| | - Charles Eaton
- Center For Primary Care and Prevention, Memorial Hospital of Rhode Island, Pawtucket, RI, USA
- Department of Family Medicine, Warren Alpert Medical School, Brown University, Providence, RI, USA
| | - Lifang Hou
- Department of Preventive Medicine, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | - Allan C Just
- Department of Environmental Medicine and Public Health, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Sonja Kunze
- Research Unit Molecular Epidemiology, Institute of Epidemiology, Helmholtz Zentrum München, German Research Center for Environmental Health, Munich/Neuherberg, Germany
- Institute of Epidemiology, Helmholtz Zentrum München, German Research Center for Environmental Health, Munich/Neuherberg, Germany
| | - Leslie Lange
- Department of Medicine, University of Colorado Denver, Anschutz Medical Campus, Aurora, CO, USA
| | - Ethan Lange
- Department of Medicine, University of Colorado Denver, Anschutz Medical Campus, Aurora, CO, USA
| | - Xihong Lin
- Veterans Affairs Normative Aging Study, Veterans Affairs Boston Healthcare System, Department of Medicine, Boston University School of Medicine, Boston, MA, USA
| | - Simin Liu
- Department of Epidemiology, School of Public Health, Brown University, Providence, RI, USA
| | | | - Alex Reiner
- Department of Epidemiology, University of Washington, Seattle, WA, USA
| | - Jincheng Shen
- Department of Population Health Sciences, School of Medicine, University of Utah, Salt Lake City, UT, USA
| | - Ben Schöttker
- Division of Clinical Epidemiology and Aging Research, German Cancer Research Center (DKFZ), Heidelberg, Germany
- Network Aging Research, University of Heidelberg, Heidelberg, Germany
| | - Pantel Vokonas
- Veterans Affairs Normative Aging Study, Veterans Affairs Boston Healthcare System, Department of Medicine, Boston University School of Medicine, Boston, MA, USA
| | - Yinan Zheng
- Department of Preventive Medicine, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | - Bessie Young
- Nephrology, Hospital and Specialty Medicine and Center for Innovation for Veteran-Centered and Value Driven Care, Veterans Affairs Puget Sound Health Care System, Seattle, WA, USA
- Division of Nephrology, Kidney Research Institute, University of Washington, Seattle, WA, USA
| | - Joel Schwartz
- Department of Environmental Health, Harvard T.H. Chan School of Public Health, Boston, MA, USA
| | - Steve Horvath
- Department of Human Genetics, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, CA, USA
| | - Ake Lu
- Department of Human Genetics, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, CA, USA
| | - Eric A Whitsel
- Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina, Chapel Hill, NC, USA
- Department of Medicine, School of Medicine, University of North Carolina, Chapel Hill, NC, USA
| | - Wolfgang Koenig
- German Center for Cardiovascular Research (DZHK), Partner Site Munich Heart Alliance, Munich, Germany
- Deutsches Herzzentrum München, Technische Universität München, Munich, Germany
- Institute of Epidemiology and Medical Biometry, University of Ulm, Ulm, Germany
| | - Jerzy Adamski
- Research Unit Molecular Endocrinology and Metabolism, Genome Analysis Center, Helmholtz Zentrum München, German Research Center for Environmental Health, Munich/Neuherberg, Germany
- Chair for Experimental Genetics, Technical University of Munich, Freising-Weihenstephan, Germany
- Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| | - Juliane Winkelmann
- Institute of Neurogenomics, Helmholtz Zentrum München, German Research Center for Environmental Health, Munich/Neuherberg, Germany
- Chair Neurogenetics, Klinikum rechts der Isar, Technical University of Munich, Munich, Germany
- Institute of Human Genetics, Klinikum rechts der Isar, Technical University of Munich, Munich, Germany
- Munich Cluster for Systems Neurology (SyNergy), Munich, Germany
| | - Hermann Brenner
- Division of Clinical Epidemiology and Aging Research, German Cancer Research Center (DKFZ), Heidelberg, Germany
- Network Aging Research, University of Heidelberg, Heidelberg, Germany
| | - Andrea A Baccarelli
- Laboratory of Precision Environmental Health, Mailman School of Public Health, Columbia University, New York, NY, USA
| | - Christian Gieger
- Research Unit Molecular Epidemiology, Institute of Epidemiology, Helmholtz Zentrum München, German Research Center for Environmental Health, Munich/Neuherberg, Germany
- Institute of Epidemiology, Helmholtz Zentrum München, German Research Center for Environmental Health, Munich/Neuherberg, Germany
| | - Annette Peters
- Institute of Epidemiology, Helmholtz Zentrum München, German Research Center for Environmental Health, Munich/Neuherberg, Germany
- German Center for Cardiovascular Research (DZHK), Partner Site Munich Heart Alliance, Munich, Germany
- German Center for Diabetes Research (DZD), Neuherberg, Germany
| | - Nora Franceschini
- Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina, Chapel Hill, NC, USA
| | - Melanie Waldenberger
- Research Unit Molecular Epidemiology, Institute of Epidemiology, Helmholtz Zentrum München, German Research Center for Environmental Health, Munich/Neuherberg, Germany.
- Institute of Epidemiology, Helmholtz Zentrum München, German Research Center for Environmental Health, Munich/Neuherberg, Germany.
- German Center for Cardiovascular Research (DZHK), Partner Site Munich Heart Alliance, Munich, Germany.
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11
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Uremic Toxins, Oxidative Stress, Atherosclerosis in Chronic Kidney Disease, and Kidney Transplantation. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2021; 2021:6651367. [PMID: 33628373 PMCID: PMC7895596 DOI: 10.1155/2021/6651367] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/31/2020] [Revised: 01/25/2021] [Accepted: 01/29/2021] [Indexed: 12/21/2022]
Abstract
Patients with chronic kidney disease (CKD) are at a high risk for cardiovascular disease (CVD), and approximately half of all deaths among patients with CKD are a direct result of CVD. The premature cardiovascular disease extends from mild to moderate CKD stages, and the severity of CVD and the risk of death increase with a decline in kidney function. Successful kidney transplantation significantly decreases the risk of death relative to long-term dialysis treatment; nevertheless, the prevalence of CVD remains high and is responsible for approximately 20-35% of mortality in renal transplant recipients. The prevalence of traditional and nontraditional risk factors for CVD is higher in patients with CKD and transplant recipients compared with the general population; however, it can only partly explain the highly increased cardiovascular burden in CKD patients. Nontraditional risk factors, unique to CKD patients, include proteinuria, disturbed calcium, and phosphate metabolism, anemia, fluid overload, and accumulation of uremic toxins. This accumulation of uremic toxins is associated with systemic alterations including inflammation and oxidative stress which are considered crucial in CKD progression and CKD-related CVD. Kidney transplantation can mitigate the impact of some of these nontraditional factors, but they typically persist to some degree following transplantation. Taking into consideration the scarcity of data on uremic waste products, oxidative stress, and their relation to atherosclerosis in renal transplantation, in the review, we discussed the impact of uremic toxins on vascular dysfunction in CKD patients and kidney transplant recipients. Special attention was paid to the role of native and transplanted kidney function.
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12
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Xia J, Cao W. Epigenetic modifications of Klotho expression in kidney diseases. J Mol Med (Berl) 2021; 99:581-592. [PMID: 33547909 DOI: 10.1007/s00109-021-02044-8] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2020] [Revised: 12/10/2020] [Accepted: 01/20/2021] [Indexed: 12/21/2022]
Abstract
Developments of many renal diseases are substantially influenced by epigenetic modifications of numerous genes, mainly mediated by DNA methylations, histone modifications, and microRNA interference; however, not all gene modifications causally affect the disease onset or progression. Klotho is a critical gene whose repressions in various pathological conditions reportedly involve epigenetic regulatory mechanisms. Klotho is almost unexceptionally repressed early after acute or chronic renal injuries and its levels inversely correlated with the disease progression and severity. Moreover, the strategies of Klotho derepression via epigenetic modulations beneficially change the pathological courses both in vitro and in vivo. Hence, Klotho is not only considered a biomarker of the renal disease but also a potential or even an ideal target of therapeutic epigenetic intervention. Here, we summarize and discuss studies that investigate the Klotho repression and intervention in renal diseases from an epigenetic point of view. These information might shed new sights into the effective therapeutic strategies to prevent and treat various renal disorders.
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Affiliation(s)
- Jinkun Xia
- Center for Organ Fibrosis and Remodeling Research, Jiangsu Key Lab of Molecular Medicine, Nanjing University School of Medicine, Nanjing, China
| | - Wangsen Cao
- Center for Organ Fibrosis and Remodeling Research, Jiangsu Key Lab of Molecular Medicine, Nanjing University School of Medicine, Nanjing, China.
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13
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Neyra JA, Hu MC, Moe OW. Klotho in Clinical Nephrology: Diagnostic and Therapeutic Implications. Clin J Am Soc Nephrol 2020; 16:162-176. [PMID: 32699047 PMCID: PMC7792642 DOI: 10.2215/cjn.02840320] [Citation(s) in RCA: 79] [Impact Index Per Article: 19.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
αKlotho (called Klotho here) is a membrane protein that serves as the coreceptor for the circulating hormone fibroblast growth factor 23 (FGF23). Klotho is also cleaved and released as a circulating substance originating primarily from the kidney and exerts a myriad of housekeeping functions in just about every organ. The vital role of Klotho is shown by the multiorgan failure with genetic deletion in rodents, with certain features reminiscent of human disease. The most common causes of systemic Klotho deficiency are AKI and CKD. Preclinical data on Klotho biology have advanced considerably and demonstrated its potential diagnostic and therapeutic value; however, multiple knowledge gaps exist in the regulation of Klotho expression, release, and metabolism; its target organs; and mechanisms of action. In the translational and clinical fronts, progress has been more modest. Nonetheless, Klotho has potential clinical applications in the diagnosis of AKI and CKD, in prognosis of progression and extrarenal complications, and finally, as replacement therapy for systemic Klotho deficiency. The overall effect of Klotho in clinical nephrology requires further technical advances and additional large prospective human studies.
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Affiliation(s)
- Javier A. Neyra
- Charles and Jane Pak Center for Mineral Metabolism and Clinical Research, Dallas, Texas
- Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, Texas
- Division of Nephrology, Bone and Mineral Metabolism, Department of Internal Medicine, University of Kentucky, Lexington, Kentucky
| | - Ming Chang Hu
- Charles and Jane Pak Center for Mineral Metabolism and Clinical Research, Dallas, Texas
- Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, Texas
| | - Orson W. Moe
- Charles and Jane Pak Center for Mineral Metabolism and Clinical Research, Dallas, Texas
- Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, Texas
- Department of Physiology, University of Texas Southwestern Medical Center, Dallas, Texas
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14
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Zhang XT, Wang G, Ye LF, Pu Y, Li RT, Liang J, Wang L, Lee KKH, Yang X. Baicalin reversal of DNA hypermethylation-associated Klotho suppression ameliorates renal injury in type 1 diabetic mouse model. Cell Cycle 2020; 19:3329-3347. [PMID: 33190590 PMCID: PMC7751632 DOI: 10.1080/15384101.2020.1843815] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2020] [Revised: 09/22/2020] [Accepted: 10/27/2020] [Indexed: 02/06/2023] Open
Abstract
Baicalin is a flavone glycoside that possesses numerous pharmacological properties. but its protective mode of action in kidney injury induced by diabetes mellitus remains incompletely understood. Using a streptozotocin (STZ)-induced diabetic mouse model, we found that baicalin could ameliorate diabetes-induced the pathological changes of the kidney function and morphology through suppressing inflammation and oxidative stress. Furthermore, baicalin treatment could alleviate interstitial fibrosis in the diabetic kidney via inhibiting epithelial-to-mesenchymal transition (EMT), which was accompanied by a sharp upregulation of Klotho, the endogenous inhibitor of renal fibrosis. We further verified that baicalin-rescued expression of Klotho was associated with Klotho promoter hypomethylation due to aberrant methyltransferase 3a expressions. Klotho knockdown via RNA interferences largely abrogated the anti-renal fibrotic effects of Baicalin in HK2 cells. These findings suggested that baicalin could alleviate renal injury-induced by diabates through partly modulating Klotho promoter methylation, which provides new insights into the treatment of diabetic nephropathy.
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Affiliation(s)
- Xiao-Tan Zhang
- International Joint Laboratory for Embryonic Development & Prenatal Medicine, Division of Histology and Embryology, Medical College, Jinan University, Guangzhou, China
- Department of Clinical Pathology, The First Affiliated Hospital of Jinan University, Guangzhou, China
| | - Guang Wang
- International Joint Laboratory for Embryonic Development & Prenatal Medicine, Division of Histology and Embryology, Medical College, Jinan University, Guangzhou, China
| | - Liu-Fang Ye
- International Joint Laboratory for Embryonic Development & Prenatal Medicine, Division of Histology and Embryology, Medical College, Jinan University, Guangzhou, China
| | - Yu Pu
- International Joint Laboratory for Embryonic Development & Prenatal Medicine, Division of Histology and Embryology, Medical College, Jinan University, Guangzhou, China
| | - Run-Tong Li
- International Joint Laboratory for Embryonic Development & Prenatal Medicine, Division of Histology and Embryology, Medical College, Jinan University, Guangzhou, China
| | - Jianxin Liang
- International Joint Laboratory for Embryonic Development & Prenatal Medicine, Division of Histology and Embryology, Medical College, Jinan University, Guangzhou, China
| | - Lijun Wang
- Department of Public Health, Medical College, Jinan University, Guangzhou, China
| | - Kenneth Ka Ho Lee
- Key Laboratory for Regenerative Medicine of the Ministry of Education, School of Biomedical Sciences, Chinese University of Hong Kong, Shatin, Hong Kong
| | - Xuesong Yang
- International Joint Laboratory for Embryonic Development & Prenatal Medicine, Division of Histology and Embryology, Medical College, Jinan University, Guangzhou, China
- Key Laboratory for Regenerative Medicine of the Ministry of Education, Jinan University, Guangzhou, China
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15
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Nowak N. Protective factors as biomarkers and targets for prevention and treatment of diabetic nephropathy: From current human evidence to future possibilities. J Diabetes Investig 2020; 11:1085-1096. [PMID: 32196975 PMCID: PMC7477513 DOI: 10.1111/jdi.13257] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/28/2019] [Revised: 03/03/2020] [Accepted: 03/17/2020] [Indexed: 12/16/2022] Open
Abstract
Although hyperglycemia, high blood pressure and aging increase the risk of developing kidney complications, some diabetes patients exposed to these risk factors do not develop kidney disease, suggesting the presence of endogenous protective factors. There is a growing need to understand these factors determining protection of the kidney in order to improve the design of preventive strategies and to enhance the processes responsible for renoprotection. The aim of this review was to present the existing molecular and epidemiological data on factors showing protective effects in diabetic kidney disease, and to summarize the evidence regarding their potential in the area of future clinical diagnostics, therapeutics and early preventive strategies. These include transcriptomic and proteomic studies regarding the anti-inflammatory, anti-fibrotic and regenerative factors that were associated with slower progression of renal function loss. Another focus is the new evidence regarding the evaluation of alterations in the regulatory epigenome and its involvement in the risk of diabetic kidney disease. Further effort is required to validate and extend these findings, and to define their potential for clinical implementation in the future.
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Affiliation(s)
- Natalia Nowak
- Faculty of MedicineCenter for Bioinformatics and Data AnalysisMedical University of BialystokBialystokPoland
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16
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Provenzano M, De Nicola L, Pena MJ, Capitoli G, Garofalo C, Borrelli S, Gagliardi I, Antolini L, Andreucci M. Precision Nephrology Is a Non-Negligible State of Mind in Clinical Research: Remember the Past to Face the Future. Nephron Clin Pract 2020; 144:463-478. [PMID: 32810859 DOI: 10.1159/000508983] [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] [Received: 02/25/2020] [Accepted: 05/26/2020] [Indexed: 11/19/2022] Open
Abstract
CKD is a major public health problem. It is characterized by a multitude of risk factors that, when aggregated, can strongly modify outcome. While major risk factors, namely, albuminuria and low estimated glomerular filtration rate (eGFR) have been well analyzed, a large variability in disease progression still remains. This happens because (1) the weight of each risk factor varies between populations (general population or CKD cohort), countries, and single individuals and (2) response to nephroprotective drugs is so heterogeneous that a non-negligible part of patients maintains a high cardiorenal risk despite optimal treatment. Precision nephrology aims at individualizing cardiorenal prognosis and therapy. The purpose of this review is to focus on the risk stratification in different areas, such as clinical practice, population research, and interventional trials, and to describe the strategies used in observational or experimental studies to afford individual-level evidence. The future of precision nephrology is also addressed. Observational studies can in fact provide more adequate findings by collecting more information on risk factors and building risk prediction models that can be applied to each individual in a reliable fashion. Similarly, new clinical trial designs can reduce the individual variability in response to treatment and improve individual outcomes.
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Affiliation(s)
- Michele Provenzano
- Renal Unit, Department of Health Sciences, "Magna Graecia" University, Catanzaro, Italy,
| | - Luca De Nicola
- Renal Unit, Department of Advanced Medical and Surgical Sciences, University of Campania "Luigi Vanvitelli,", Naples, Italy
| | - Michelle J Pena
- Department of Clinical Pharmacy and Pharmacology, University Medical Center Groningen, Groningen, The Netherlands
| | - Giulia Capitoli
- Center of Biostatistics for Clinical Epidemiology, School of Medicine and Surgery, University of Milano-Bicocca, Monza, Italy
| | - Carlo Garofalo
- Renal Unit, Department of Advanced Medical and Surgical Sciences, University of Campania "Luigi Vanvitelli,", Naples, Italy
| | - Silvio Borrelli
- Renal Unit, Department of Advanced Medical and Surgical Sciences, University of Campania "Luigi Vanvitelli,", Naples, Italy
| | - Ida Gagliardi
- Renal Unit, Department of Health Sciences, "Magna Graecia" University, Catanzaro, Italy
| | - Laura Antolini
- Center of Biostatistics for Clinical Epidemiology, School of Medicine and Surgery, University of Milano-Bicocca, Monza, Italy
| | - Michele Andreucci
- Renal Unit, Department of Health Sciences, "Magna Graecia" University, Catanzaro, Italy
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17
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Vervloet MG. FGF23 measurement in chronic kidney disease: What is it really reflecting? Clin Chim Acta 2020; 505:160-166. [PMID: 32156608 DOI: 10.1016/j.cca.2020.03.013] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2020] [Revised: 03/05/2020] [Accepted: 03/06/2020] [Indexed: 12/20/2022]
Abstract
Fibroblast growth factor can be measured in clinical practice using ELISA, with acceptable validity. Different from many metabolites and minerals, its value can differ by a thousand-fold between individuals, largely because of differences in kidney function and dietary habits. This wide range complicates the proper interpretation of the concentration of FGF23, both in terms of the appropriateness of a given value for a given estimated GFR, and in terms of estimating the magnitude of risk for clinical events, with which FGF23 is clearly associated. In this narrative review, the impact of kidney function, exposure to phosphate from diet, and novel emerging factors that influence FGF23 concentrations are discussed. These and yet to define determinants of FGF23 question the causality of the association of FGF23 with hard (cardiovascular) endpoints, as observed in several epidemiological studies.
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Affiliation(s)
- Marc G Vervloet
- Amsterdam University Medical Center, Department of Nephrology, and Amsterdam Cardiovascular Sciences (ACS), Meibergdreef 9, 1105 AZ Amsterdam, the Netherlands.
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18
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Cheikhi A, Barchowsky A, Sahu A, Shinde SN, Pius A, Clemens ZJ, Li H, Kennedy CA, Hoeck JD, Franti M, Ambrosio F. Klotho: An Elephant in Aging Research. J Gerontol A Biol Sci Med Sci 2020; 74:1031-1042. [PMID: 30843026 DOI: 10.1093/gerona/glz061] [Citation(s) in RCA: 44] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2018] [Indexed: 12/12/2022] Open
Abstract
The year 2017 marked the 20th anniversary of the first publication describing Klotho. This single protein was and is remarkable in that its absence in mice conferred an accelerated aging, or progeroid, phenotype with a dramatically shortened life span. On the other hand, genetic overexpression extended both health span and life span by an impressive 30%. Not only has Klotho deficiency been linked to a number of debilitating age-related illnesses but many subsequent reports have lent credence to the idea that Klotho can compress the period of morbidity and extend the life span of both model organisms and humans. This suggests that Klotho functions as an integrator of organ systems, making it both a promising tool for advancing our understanding of the biology of aging and an intriguing target for interventional studies. In this review, we highlight advances in our understanding of Klotho as well as key challenges that have somewhat limited our view, and thus translational potential, of this potent protein.
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Affiliation(s)
- Amin Cheikhi
- Department of Physical Medicine and Rehabilitation, University of Pittsburgh.,Division of Geriatric Medicine, Department of Medicine, University of Pittsburgh
| | - Aaron Barchowsky
- Department of Environmental and Occupational Health, University of Pittsburgh.,Department of Pharmacology and Chemical Biology, University of Pittsburgh
| | - Amrita Sahu
- Department of Physical Medicine and Rehabilitation, University of Pittsburgh.,Department of Environmental and Occupational Health, University of Pittsburgh
| | - Sunita N Shinde
- Department of Physical Medicine and Rehabilitation, University of Pittsburgh
| | - Abish Pius
- Department of Physical Medicine and Rehabilitation, University of Pittsburgh
| | - Zachary J Clemens
- Department of Physical Medicine and Rehabilitation, University of Pittsburgh
| | - Hua Li
- Department of Biotherapeutics Discovery, Research Division, Boehringer Ingelheim Pharmaceuticals, Inc. Ridgefield, Connecticut
| | - Charles A Kennedy
- Department of Research Beyond Borders, Regenerative Medicine, Boehringer Ingelheim Pharmaceuticals, Inc. Ridgefield, Connecticut
| | - Joerg D Hoeck
- Department of Research Beyond Borders, Regenerative Medicine, Boehringer Ingelheim Pharmaceuticals, Inc. Ridgefield, Connecticut
| | - Michael Franti
- Department of Research Beyond Borders, Regenerative Medicine, Boehringer Ingelheim Pharmaceuticals, Inc. Ridgefield, Connecticut
| | - Fabrisia Ambrosio
- Department of Physical Medicine and Rehabilitation, University of Pittsburgh.,Department of Environmental and Occupational Health, University of Pittsburgh.,Department of Bioengineering, University of Pittsburgh, Pennsylvania.,McGowan Institute for Regenerative Medicine, University of Pittsburgh, Pennsylvania
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19
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Lacroix JS, Urena-Torres P. Potentielle application de l’axe fibroblast growth factor 23-Klotho dans la maladie rénale chronique. Nephrol Ther 2020; 16:83-92. [DOI: 10.1016/j.nephro.2019.05.003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2019] [Accepted: 05/19/2019] [Indexed: 12/17/2022]
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20
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The Signaling of Cellular Senescence in Diabetic Nephropathy. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2019; 2019:7495629. [PMID: 31687085 PMCID: PMC6794967 DOI: 10.1155/2019/7495629] [Citation(s) in RCA: 103] [Impact Index Per Article: 20.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/19/2019] [Revised: 07/03/2019] [Accepted: 07/23/2019] [Indexed: 12/13/2022]
Abstract
Diabetic nephropathy is the leading cause of chronic kidney disease (CKD) in western countries. Notably, it has a rapidly rising prevalence in China. The patients, commonly complicated with cardiovascular diseases and neurologic disorders, are at high risk to progress into end-stage renal disease (ESRD) and death. However, the pathogenic mechanisms of diabetic nephropathy have not been determined. Cellular senescence, which recently has gained broad attention, is thought to be an important player in the onset and development of diabetic nephropathy. In this issue, we generally review the mechanisms of cellular senescence in diabetic nephropathy, which involve telomere attrition, DNA damage, epigenetic alterations, mitochondrial dysfunction, loss of Klotho, Wnt/β-catenin signaling activation, persistent inflammation, and accumulation of uremic toxins. Moreover, we highlight the potential therapeutic targets of cellular senescence in diabetic nephropathy and provide important clues for clinical strategies.
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21
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Vervloet M. Modifying Phosphate Toxicity in Chronic Kidney Disease. Toxins (Basel) 2019; 11:E522. [PMID: 31505780 PMCID: PMC6784221 DOI: 10.3390/toxins11090522] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2019] [Revised: 08/29/2019] [Accepted: 09/05/2019] [Indexed: 02/06/2023] Open
Abstract
Phosphate toxicity is a well-established phenomenon, especially in chronic kidney disease (CKD), where hyperphosphatemia is a frequent occurrence when CKD is advanced. Many therapeutic efforts are targeted at phosphate, and comprise dietary intervention, modifying dialysis schemes, treating uncontrolled hyperparathyroidism and importantly, phosphate binder therapy. Despite all these interventions, hyperphosphatemia persists in many, and its pathological influence is ongoing. In nephrological care, a somewhat neglected aspect of treatment-when attempts fail to lower exposure to a toxin like phosphate-is to explore the possibility of "anti-dotes". Indeed, quite a long list of factors modify, or are mediators of phosphate toxicity. Addressing these, especially when phosphate itself cannot be sufficiently controlled, may provide additional protection. In this narrative overview, several factors are discussed that may qualify as either such a modifier or mediator, that can be influenced by other means than simply lowering phosphate exposure. A wider scope when targeting phosphate-induced comorbidity in CKD, in particular cardiovascular disease, may alleviate the burden of disease that is the consequence of this potentially toxic mineral in CKD.
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Affiliation(s)
- Marc Vervloet
- Department of Nephrology and Amsterdam Cardiovascular Sciences, Amsterdam University Medical Center, De Boelelaan 1117, 1081 HV Amsterdam, The Netherlands.
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22
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Jiang W, Xiao T, Han W, Xiong J, He T, Liu Y, Huang Y, Yang K, Bi X, Xu X, Yu Y, Li Y, Gu J, Zhang J, Huang Y, Zhang B, Zhao J. Klotho inhibits PKCα/p66SHC-mediated podocyte injury in diabetic nephropathy. Mol Cell Endocrinol 2019; 494:110490. [PMID: 31207271 DOI: 10.1016/j.mce.2019.110490] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/29/2019] [Revised: 06/12/2019] [Accepted: 06/12/2019] [Indexed: 10/26/2022]
Abstract
Diabetic nephropathy (DN) is a progressive disease, the main pathogeny of which is podocyte injury. As a calcium-dependent serine/threonine protein kinase involved in podocyte injury, protein kinase C isoform α (PKCα) was reported to regulate the phosphorylation of p66SHC. However, the role of PKCα/p66SHC in DN remains unknown. Klotho, an anti-aging protein with critical roles in protecting kidney, is expressed predominantly in the kidney and secreted in the blood. Nonetheless, the mechanism underlying amelioration of podocyte injury by Klotho in DN remains unclear. Our data showed that Klotho was decreased in STZ-treated mice and was further declined in diabetic KL ± mice. As expected, Klotho deficiency aggravated diabetes-induced proteinuria and podocyte injury, accompanied by the activation of PKCα and p66SHC. In contrast, overexpression of Klotho partially ameliorated PKCα/p66SHC-mediated podocyte injury and proteinuria. In addition, in vitro experiments showed that activation of PKCα and subsequently increased intracellular reactive oxygen species (ROS) was involved in podocytic apoptosis induced by high glucose (HG), which could be partially reversed by Klotho. Hence, we conclude that Klotho might inhibit PKCα/p66SHC-mediated podocyte injury in diabetic nephropathy.
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Affiliation(s)
- Wei Jiang
- Department of Nephrology, Institute of Nephrology of Chongqing and Kidney Center of PLA, Xinqiao Hospital, Third Military Medical University, Chongqing, China
| | - Tangli Xiao
- Department of Nephrology, Institute of Nephrology of Chongqing and Kidney Center of PLA, Xinqiao Hospital, Third Military Medical University, Chongqing, China
| | - Wenhao Han
- Department of Nephrology, Institute of Nephrology of Chongqing and Kidney Center of PLA, Xinqiao Hospital, Third Military Medical University, Chongqing, China
| | - Jiachuan Xiong
- Department of Nephrology, Institute of Nephrology of Chongqing and Kidney Center of PLA, Xinqiao Hospital, Third Military Medical University, Chongqing, China
| | - Ting He
- Department of Nephrology, Institute of Nephrology of Chongqing and Kidney Center of PLA, Xinqiao Hospital, Third Military Medical University, Chongqing, China
| | - Yong Liu
- Department of Nephrology, Institute of Nephrology of Chongqing and Kidney Center of PLA, Xinqiao Hospital, Third Military Medical University, Chongqing, China
| | - Yinghui Huang
- Department of Nephrology, Institute of Nephrology of Chongqing and Kidney Center of PLA, Xinqiao Hospital, Third Military Medical University, Chongqing, China
| | - Ke Yang
- Department of Nephrology, Institute of Nephrology of Chongqing and Kidney Center of PLA, Xinqiao Hospital, Third Military Medical University, Chongqing, China
| | - Xianjin Bi
- Department of Nephrology, Institute of Nephrology of Chongqing and Kidney Center of PLA, Xinqiao Hospital, Third Military Medical University, Chongqing, China
| | - Xinli Xu
- Department of Nephrology, Institute of Nephrology of Chongqing and Kidney Center of PLA, Xinqiao Hospital, Third Military Medical University, Chongqing, China
| | - Yanlin Yu
- Department of Nephrology, Institute of Nephrology of Chongqing and Kidney Center of PLA, Xinqiao Hospital, Third Military Medical University, Chongqing, China
| | - Yan Li
- Department of Nephrology, Institute of Nephrology of Chongqing and Kidney Center of PLA, Xinqiao Hospital, Third Military Medical University, Chongqing, China
| | - Jun Gu
- State Key Laboratory of Protein and Plant Gene Research, College of Life Science, Peking University, Beijing, China
| | - Jingbo Zhang
- Department of Nephrology, Institute of Nephrology of Chongqing and Kidney Center of PLA, Xinqiao Hospital, Third Military Medical University, Chongqing, China
| | - Yunjian Huang
- Department of Nephrology, Institute of Nephrology of Chongqing and Kidney Center of PLA, Xinqiao Hospital, Third Military Medical University, Chongqing, China
| | - Bo Zhang
- Department of Nephrology, Institute of Nephrology of Chongqing and Kidney Center of PLA, Xinqiao Hospital, Third Military Medical University, Chongqing, China.
| | - Jinghong Zhao
- Department of Nephrology, Institute of Nephrology of Chongqing and Kidney Center of PLA, Xinqiao Hospital, Third Military Medical University, Chongqing, China.
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23
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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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Wei H, Li H, Song X, Du X, Cai Y, Li C, Dong L, Dong J. Serum klotho: a potential predictor of cerebrovascular disease in hemodialysis patients. BMC Nephrol 2019; 20:63. [PMID: 30791885 PMCID: PMC6385422 DOI: 10.1186/s12882-019-1232-2] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2017] [Accepted: 01/25/2019] [Indexed: 12/15/2022] Open
Abstract
BACKGROUND Hemodialysis patients suffer from a serious threat of cerebrovascular disease. Klotho, as an aging-suppressor gene, contributes to protect on vascular calcification and oxidative stress, which are the risk factors of cerebrovascular disease. The purpose of the present study is to determine the relationship between serum klotho and cerebrovascular disease in patients receiving hemodialysis. METHODS Serum klotho levels of hemodialysis patients were measured by ELISA. Cerebrovascular diseases were diagnosed by CT or MRI scans. The cognitive function of hemodialysis patients with cerebrovascular disease were evaluated with a neuropsychological battery assessing domains of global cognition verbal memory, spatial memory, executive function and verbal fluency. RESULTS Eighty-eight patients were included, 57 ± 14 years, 63.64% male, 52.27% older than 60 years. Twenty-eight participants had cerebrovascular disease (23 cases had cerebral infarction, 5 cases had cerebral hemorrhage). The average level of serum klotho of all participants was 119.10 ± 47.29 pg/ml. The serum klotho level was significantly associated with cerebrovascular disease in hemodialysis patients (HR(95%CI) = 0.975(0.960-0.990), p = 0.001). The optimal cut-off value of serum klotho for predicting cerebrovascular disease in hemodialysis patients was 137.22 pg/ml, with a specificity of 96.4% and a sensitivity of 46.7%. But serum klotho was not an independent risk factor of cognitive impairment for hemodialysis patients with cerebrovascular disease (HR((95%CI) = 1.002(0.986-1.018), p = 0.776) or with cerebral infarction (HR(95%CI) = 1.005(0.987-1.023), p = 0.576). CONCLUSIONS The serum klotho level is a potential predictor of cerebrovascular disease in hemodialysis patients, but it is not an independent risk factor of cognitive impairment for hemodialysis patients with cerebrovascular disease.
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Affiliation(s)
- Honglan Wei
- Department of Nephrology, Puai Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, 430033, People's Republic of China
| | - Hua Li
- Department of Nephrology, Puai Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, 430033, People's Republic of China
| | - Xiaohong Song
- Department of Nephrology, Puai Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, 430033, People's Republic of China
| | - Xingguo Du
- Department of Nephrology, Puai Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, 430033, People's Republic of China
| | - Yuan Cai
- Department of Nephrology, Puai Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, 430033, People's Republic of China
| | - Chengxu Li
- Department of Nephrology, Puai Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, 430033, People's Republic of China
| | - Liping Dong
- Department of Nephrology, Puai Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, 430033, People's Republic of China
| | - Junwu Dong
- Department of Nephrology, Puai Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, 430033, People's Republic of China.
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25
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Liu WC, Tomino Y, Lu KC. Impacts of Indoxyl Sulfate and p-Cresol Sulfate on Chronic Kidney Disease and Mitigating Effects of AST-120. Toxins (Basel) 2018; 10:toxins10090367. [PMID: 30208594 PMCID: PMC6162782 DOI: 10.3390/toxins10090367] [Citation(s) in RCA: 113] [Impact Index Per Article: 18.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2018] [Revised: 09/07/2018] [Accepted: 09/08/2018] [Indexed: 02/07/2023] Open
Abstract
Uremic toxins, such as indoxyl sulfate (IS) and p-cresol, or p-cresyl sulfate (PCS), are markedly accumulated in the organs of chronic kidney disease (CKD) patients. These toxins can induce inflammatory reactions and enhance oxidative stress, prompting glomerular sclerosis and interstitial fibrosis, to aggravate the decline of renal function. Consequently, uremic toxins play an important role in the worsening of renal and cardiovascular functions. Furthermore, they destroy the quantity and quality of bone. Oral sorbent AST-120 reduces serum levels of uremic toxins in CKD patients by adsorbing the precursors of IS and PCS generated by amino acid metabolism in the intestine. Accordingly, AST-120 decreases the serum IS levels and reduces the production of reactive oxygen species by endothelial cells, to impede the subsequent oxidative stress. This slows the progression of cardiovascular and renal diseases and improves bone metabolism in CKD patients. Although large-scale studies showed no obvious benefits from adding AST-120 to the standard therapy for CKD patients, subsequent sporadic studies may support its use. This article summarizes the mechanisms of the uremic toxins, IS, and PCS, and discusses the multiple effects of AST-120 in CKD patients.
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Affiliation(s)
- Wen-Chih Liu
- Division of Nephrology, Department of Internal Medicine, Tungs' Taichung Metro Harbor Hospital, Taichung City 435, Taiwan.
- Graduate Institute of Clinical Medicine, College of Medicine, Taipei Medical University, Taipei 106, Taiwan.
| | - Yasuhiko Tomino
- Asian Pacific Renal Research Promotion Office, Medical Corporation SHOWAKAI, Tokyo 160-0023, Japan.
| | - Kuo-Cheng Lu
- Division of Nephrology, Department of Medicine, Fu-Jen Catholic University Hospital, School of Medicine, Fu-Jen Catholic University, New Taipei City 243, Taiwan.
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Correlation between Soluble α-Klotho and Renal Function in Patients with Chronic Kidney Disease: A Review and Meta-Analysis. BIOMED RESEARCH INTERNATIONAL 2018; 2018:9481475. [PMID: 30159331 PMCID: PMC6109492 DOI: 10.1155/2018/9481475] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/15/2017] [Revised: 05/29/2018] [Accepted: 07/11/2018] [Indexed: 01/11/2023]
Abstract
Objective Over decades, numerous inconsistent studies are reported on the relationship between soluble α-Klotho and renal function in patients with chronic kidney disease (CKD). This study aims to perform a meta-analysis to figure out the correlations between soluble α-Klotho and renal function in patients with CKD. Materials and Methods We searched medical and scientific literature databases, PubMed and EMBASE (from the inception to October 2017), for publications that reported studies on associations between soluble α-Klotho and renal function in patients with CKD. Only publications in English were extracted. Summary correlation coefficient (r) values were extracted from each study, and 95% confidence intervals (CIs) were calculated. Publication bias was tested, and sensitivity and subgroup analyses were performed to investigate potential heterogeneity. Results Of 611 studies, 9 publications with 1457 patients were included into the analysis. The following data were extracted from the literature: first author, year of publication, research region, research index, sample size, average age and Pearson or Spearman correlation coefficient, study design, the αKlotho/FGF23 assays utilized, full length, or the C-terminal fragment of FGF23. The pooled r between α-Klotho and estimated glomerular filtration rate (eGFR), FGF-23 were 0.35 (95%CI, 0.23~0.46, and P<0.05), -0.10 (95%CI, -0.19~-0.01, and P<0.05) with remarkable significance, indicating moderate heterogeneity. There was no significant heterogeneity between subgroups in analyses of α-Klotho and eGFR stratified by research region, mean age, and eGFR, but heterogeneity exists in analyses of α-Klotho and FGF-23 stratified by research region. There was no significant correlation between a-klotho and Ca and PTH and PHOS. There was no evidence of publication bias with Egger's test (p=0.360) or with Begg's test (p=0.902) and the distribution of funnel plots was symmetrical in all of our analysis. Conclusions There exists a significant positive correlation between soluble α-Klotho and eGFR in patients with CKD. Also, a significant negative correlation between α-Klotho and FGF23 levels is proven. This raises hope to employ αKlotho and FGF23 as early biomarkers of CKD. However, further large prospective follow-up researches are needed to validate this hypothesis and to explore whether maintaining or elevating the Klotho level could improve renal function and complications in CKD patients.
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27
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Wang JJ, Chi NH, Huang TM, Connolly R, Chen LW, Chueh SCJ, Kan WC, Lai CC, Wu VC, Fang JT, Chu TS, Wu KD. Urinary biomarkers predict advanced acute kidney injury after cardiovascular surgery. CRITICAL CARE : THE OFFICIAL JOURNAL OF THE CRITICAL CARE FORUM 2018; 22:108. [PMID: 29699579 PMCID: PMC5921971 DOI: 10.1186/s13054-018-2035-8] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/21/2017] [Accepted: 04/09/2018] [Indexed: 02/08/2023]
Abstract
BACKGROUND Acute kidney injury (AKI) after cardiovascular surgery is a serious complication. Little is known about the ability of novel biomarkers in combination with clinical risk scores for prediction of advanced AKI. METHODS In this prospectively conducted multicenter study, urine samples were collected from 149 adults at 0, 3, 6, 12 and 24 h after cardiovascular surgery. We measured urinary hemojuvelin (uHJV), kidney injury molecule-1 (uKIM-1), neutrophil gelatinase-associated lipocalin (uNGAL), α-glutathione S-transferase (uα-GST) and π-glutathione S-transferase (uπ-GST). The primary outcome was advanced AKI, under the definition of Kidney Disease: Improving Global Outcomes (KDIGO) stage 2, 3 and composite outcomes were KDIGO stage 2, 3 or 90-day mortality after hospital discharge. RESULTS Patients with advanced AKI had significantly higher levels of uHJV and uKIM-1 at 3, 6 and 12 h after surgery. When normalized by urinary creatinine level, uKIM-1 in combination with uHJV at 3 h post-surgery had a high predictive ability for advanced AKI and composite outcome (AUC = 0.898 and 0.905, respectively). The combination of this biomarker panel (normalized uKIM-1, uHJV at 3 h post-operation) and Liano's score was superior in predicting advanced AKI (AUC = 0.931, category-free net reclassification improvement of 1.149, and p < 0.001). CONCLUSIONS When added to Liano's score, normalized uHJV and uKIM-1 levels at 3 h after cardiovascular surgery enhanced the identification of patients at higher risk of progression to advanced AKI and composite outcomes.
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Affiliation(s)
- Jian-Jhong Wang
- Division of Nephrology, Department of Internal Medicine, Chi Mei Medical Center, Liouying, Tainan, Taiwan.,NSARF group (National Taiwan University Hospital Study Group of ARF), Taipei, Taiwan
| | - Nai-Hsin Chi
- Department of Surgery, National Taiwan University Hospital, Taipei, Taiwan
| | - Tao-Min Huang
- NSARF group (National Taiwan University Hospital Study Group of ARF), Taipei, Taiwan.,Division of Nephrology, Department of Internal Medicine, National Taiwan University Hospital, Taipei, Taiwan
| | - Rory Connolly
- School of Biotechnology, Dublin City University, Glasnevin, Dublin 9, Ireland
| | - Liang Wen Chen
- Department of Surgery, National Taiwan University Hospital, Taipei, Taiwan
| | - Shih-Chieh Jeff Chueh
- Cleveland Clinic Lerner College of Medicine and Glickman Urological and Kidney Institute, Cleveland Clinic, Cleveland, USA
| | - Wei-Chih Kan
- Division of Nephrology, Department of Internal Medicine, Chi-Mei Medical Center, Tainan, Taiwan
| | - Chih-Cheng Lai
- Department of Intensive Care Medicine, Chi Mei Medical Center, Liouying, Tainan, Taiwan
| | - Vin-Cent Wu
- NSARF group (National Taiwan University Hospital Study Group of ARF), Taipei, Taiwan. .,Division of Nephrology, Department of Internal Medicine, National Taiwan University Hospital, Taipei, Taiwan.
| | - Ji-Tseng Fang
- Chang Gung University College of Medicine, Taoyuan, Taiwan.,Kidney Research Center, Department of Nephrology, Chang Gung Memorial Hospital, Taoyuan City, Taiwan
| | - Tzong-Shinn Chu
- NSARF group (National Taiwan University Hospital Study Group of ARF), Taipei, Taiwan.,Division of Nephrology, Department of Internal Medicine, National Taiwan University Hospital, Taipei, Taiwan
| | - Kwan-Dun Wu
- NSARF group (National Taiwan University Hospital Study Group of ARF), Taipei, Taiwan.,Division of Nephrology, Department of Internal Medicine, National Taiwan University Hospital, Taipei, Taiwan
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28
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Kimura T, Shiizaki K, Akimoto T, Shinzato T, Shimizu T, Kurosawa A, Kubo T, Nanmoku K, Kuro-O M, Yagisawa T. The impact of preserved Klotho gene expression on antioxidative stress activity in healthy kidney. Am J Physiol Renal Physiol 2018; 315:F345-F352. [PMID: 29693450 DOI: 10.1152/ajprenal.00486.2017] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Klotho, which was originally identified as an antiaging gene, forms a complex with fibroblast growth factor 23 receptor in the kidney, with subsequent signaling that regulates mineral metabolism. Other biological activities of Klotho, including antiaging effects such as protection from various types of cellular stress, have been shown; however, the precise mechanism of these effects of Klotho gene in the healthy human kidney is not well understood. In this study, we examined the relationships of Klotho and antioxidative stress gene expression levels in zero-hour biopsy specimens from 44 donors in kidney transplantation and verified them in animal models whose Klotho gene expression levels were varied. The nitrotyrosine expression level in the kidney was evaluated in these animal models. Expression levels of Klotho gene were positively correlated with the p53 gene and antioxidant enzyme genes such as catalase, superoxide dismutase 1 (SOD1), SOD2, peroxiredoxin 3 (PRDX3), and glutathione peroxidase 1 (GPX1) but not clinical parameters such as age and renal function or pathological features such as glomerulosclerosis and interstitial fibrosis tubular atrophy. The expression levels of all genes were significantly higher in mice with Klotho overexpression than in wild-type mice, and those except for catalase, PRDX3, and GPX1 were significantly lower in Klotho-deficient mice than in wild-type littermate mice. Nitrotyrosine-positive bands of various sizes were observed in kidney from Klotho-deficient mice only. The preservation of Klotho gene expression might induce the antioxidative stress mechanism for homeostasis of healthy human kidney independently of its general condition, including age, renal function, and histological findings.
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Affiliation(s)
- Takaaki Kimura
- Division of Renal Surgery and Transplantation, Department of Urology, Jichi Medical University, Shimotsuke, Tochigi , Japan
| | - Kazuhiro Shiizaki
- Division of Anti-aging Medicine, Center for Molecular Medicine, Jichi Medical University, Shimotsuke, Tochigi , Japan
| | - Tetsu Akimoto
- Division of Nephrology, Department of Internal Medicine, Jichi Medical University, Shimotsuke, Tochigi , Japan
| | - Takahiro Shinzato
- Division of Renal Surgery and Transplantation, Department of Urology, Jichi Medical University, Shimotsuke, Tochigi , Japan
| | - Toshihiro Shimizu
- Division of Renal Surgery and Transplantation, Department of Urology, Jichi Medical University, Shimotsuke, Tochigi , Japan
| | - Akira Kurosawa
- Division of Renal Surgery and Transplantation, Department of Urology, Jichi Medical University, Shimotsuke, Tochigi , Japan
| | - Taro Kubo
- Division of Renal Surgery and Transplantation, Department of Urology, Jichi Medical University, Shimotsuke, Tochigi , Japan
| | - Koji Nanmoku
- Division of Renal Surgery and Transplantation, Department of Urology, Jichi Medical University, Shimotsuke, Tochigi , Japan
| | - Makoto Kuro-O
- Division of Anti-aging Medicine, Center for Molecular Medicine, Jichi Medical University, Shimotsuke, Tochigi , Japan
| | - Takashi Yagisawa
- Division of Renal Surgery and Transplantation, Department of Urology, Jichi Medical University, Shimotsuke, Tochigi , Japan
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29
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Gazdhar A, Ravikumar P, Pastor J, Heller M, Ye J, Zhang J, Moe OW, Geiser T, Hsia CCW. Alpha-Klotho Enrichment in Induced Pluripotent Stem Cell Secretome Contributes to Antioxidative Protection in Acute Lung Injury. Stem Cells 2017; 36:616-625. [PMID: 29226550 DOI: 10.1002/stem.2752] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2017] [Revised: 11/07/2017] [Accepted: 11/21/2017] [Indexed: 02/06/2023]
Abstract
Induced pluripotent stem cells (iPSCs) have been reported to alleviate organ injury, although the mechanisms of action remain unclear and administration of intact cells faces many limitations. We hypothesized that cell-free conditioned media (CM) containing the secretome of iPSCs possess antioxidative constituents that can alleviate pulmonary oxidant stress damage. We derived iPSCs from human dermal fibroblasts and harvested the CM. Addition of iPSC CM to cultured human alveolar type-1 epithelial cells mitigated hyperoxia-induced depletion of endogenous total antioxidant capacity while tracheal instillation of iPSC CM into adult rat lungs enhanced hyperoxia-induced increase in TAC. In both the in vitro and in vivo models, iPSC CM ameliorated oxidative damage to DNA, lipid, and protein, and activated the nuclear factor (erythroid 2)-related factor 2 (Nrf2) network of endogenous antioxidant proteins. Compared with control fibroblast-conditioned or cell-free media, iPSC CM is highly enriched with αKlotho at a concentration up to more than 10-fold of that in normal serum. αKlotho is an essential antioxidative cell maintenance and protective factor and an activator of the Nrf2 network. Immunodepletion of αKlotho reduced iPSC CM-mediated cytoprotection by ∼50%. Thus, the abundant αKlotho content significantly contributes to iPSC-mediated antioxidation and cytoprotection. Results uncover a major mechanism of iPSC action, suggest a fundamental role of αKlotho in iPSC maintenance, and support the translational potential of airway delivery of cell-free iPSC secretome for protection against lung injury. The targeted cell-free secretome-based approach may also be applicable to the amelioration of injury in other organs. Stem Cells 2018;36:616-625.
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Affiliation(s)
- Amiq Gazdhar
- Department of Pulmonary Medicine, University Hospital, Bern, Switzerland.,Department of Clinical Research, University Hospital, Bern, Switzerland
| | - Priya Ravikumar
- Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, Texas, USA.,Charles and Jane Pak Center of Mineral Metabolism and Clinical Research, University of Texas Southwestern Medical Center, Dallas, Texas, USA
| | - Johanne Pastor
- Charles and Jane Pak Center of Mineral Metabolism and Clinical Research, University of Texas Southwestern Medical Center, Dallas, Texas, USA
| | - Manfred Heller
- Department of Clinical Research, University Hospital, Bern, Switzerland
| | - Jianfeng Ye
- Charles and Jane Pak Center of Mineral Metabolism and Clinical Research, University of Texas Southwestern Medical Center, Dallas, Texas, USA
| | - Jianning Zhang
- Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, Texas, USA.,Charles and Jane Pak Center of Mineral Metabolism and Clinical Research, University of Texas Southwestern Medical Center, Dallas, Texas, USA
| | - Orson W Moe
- Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, Texas, USA.,Charles and Jane Pak Center of Mineral Metabolism and Clinical Research, University of Texas Southwestern Medical Center, Dallas, Texas, USA.,Department of Physiology, University of Texas Southwestern Medical Center, Dallas, Texas, USA
| | - Thomas Geiser
- Department of Pulmonary Medicine, University Hospital, Bern, Switzerland.,Department of Clinical Research, University Hospital, Bern, Switzerland
| | - Connie C W Hsia
- Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, Texas, USA
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30
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He L, Wei Q, Liu J, Yi M, Liu Y, Liu H, Sun L, Peng Y, Liu F, Venkatachalam MA, Dong Z. AKI on CKD: heightened injury, suppressed repair, and the underlying mechanisms. Kidney Int 2017; 92:1071-1083. [PMID: 28890325 DOI: 10.1016/j.kint.2017.06.030] [Citation(s) in RCA: 268] [Impact Index Per Article: 38.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2017] [Revised: 06/13/2017] [Accepted: 06/19/2017] [Indexed: 02/07/2023]
Abstract
Acute kidney injury (AKI) and chronic kidney disease (CKD) are interconnected. Although AKI-to-CKD transition has been intensively studied, the information of AKI on CKD is very limited. Nonetheless, AKI, when occurring in patients with CKD, is known to be more severe and difficult to recover. CKD is associated with significant changes in cell signaling in kidney tissues, including the activation of transforming growth factor-β, p53, hypoxia-inducible factor, and major developmental pathways. At the cellular level, CKD is characterized by mitochondrial dysfunction, oxidative stress, and aberrant autophagy. At the tissue level, CKD is characterized by chronic inflammation and vascular dysfunction. These pathologic changes may contribute to the heightened sensitivity of, and nonrecovery from, AKI in patients with CKD.
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Affiliation(s)
- Liyu He
- Department of Nephrology, The Second Xiangya Hospital, Central South University, Changsha, Hunan, China
| | - Qingqing Wei
- Department of Cellular Biology and Anatomy, Medical College of Georgia at Augusta University and Charlie Norwood VA Medical Center, Augusta, Georgia, USA
| | - Jing Liu
- Department of Nephrology, The Second Xiangya Hospital, Central South University, Changsha, Hunan, China; Department of Cellular Biology and Anatomy, Medical College of Georgia at Augusta University and Charlie Norwood VA Medical Center, Augusta, Georgia, USA
| | - Mixuan Yi
- Department of Nephrology, The Second Xiangya Hospital, Central South University, Changsha, Hunan, China; Department of Cellular Biology and Anatomy, Medical College of Georgia at Augusta University and Charlie Norwood VA Medical Center, Augusta, Georgia, USA
| | - Yu Liu
- Department of Nephrology, The Second Xiangya Hospital, Central South University, Changsha, Hunan, China
| | - Hong Liu
- Department of Nephrology, The Second Xiangya Hospital, Central South University, Changsha, Hunan, China
| | - Lin Sun
- Department of Nephrology, The Second Xiangya Hospital, Central South University, Changsha, Hunan, China
| | - Youming Peng
- Department of Nephrology, The Second Xiangya Hospital, Central South University, Changsha, Hunan, China
| | - Fuyou Liu
- Department of Nephrology, The Second Xiangya Hospital, Central South University, Changsha, Hunan, China
| | - Manjeri A Venkatachalam
- Department of Pathology, University of Texas Health Science Center at San Antonio, San Antonio, Texas, USA
| | - Zheng Dong
- Department of Nephrology, The Second Xiangya Hospital, Central South University, Changsha, Hunan, China; Department of Cellular Biology and Anatomy, Medical College of Georgia at Augusta University and Charlie Norwood VA Medical Center, Augusta, Georgia, USA.
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31
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Wang WJ, Cai GY, Chen XM. Cellular senescence, senescence-associated secretory phenotype, and chronic kidney disease. Oncotarget 2017; 8:64520-64533. [PMID: 28969091 PMCID: PMC5610023 DOI: 10.18632/oncotarget.17327] [Citation(s) in RCA: 60] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2017] [Accepted: 03/24/2017] [Indexed: 12/19/2022] Open
Abstract
Chronic kidney disease (CKD) is increasingly being accepted as a type of renal ageing. The kidney undergoes age-related alterations in both structure and function. To date, a comprehensive analysis of cellular senescence and senescence-associated secretory phenotype (SASP) in CKD is lacking. Hence, this review mainly discusses the relationship between the two phenomena to show the striking similarities between SASP and CKD-associated secretory phenotype (CASP). It has been reported that replicative senescence, stress-induced premature ageing, and epigenetic abnormalities participate in the occurrence and development of CKD. Genomic damage and external environmental stimuli cause increased levels of oxidative stress and a chronic inflammatory state as a result of irreversible cell cycle arrest and low doses of SASP. Similar to SASP, CASP factors activate tissue repair by multiple mechanisms. Once tissue repair fails, the accumulated SASP or CASP species aggravate DNA damage response (DDR) and cause the senescent cells to secrete more SASP factors, accelerating the process of cellular ageing and eventually leading to various ageing-related changes. It is concluded that cellular senescence and SASP participate in the pathological process of CKD, and correspondingly CKD accelerated the progression of cell senescence and the secretion of SASP. These results will facilitate the integration of these mechanisms into the care and management of CKD and other age-related diseases.
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Affiliation(s)
- Wen-Juan Wang
- Department of Nephrology, Chinese PLA General Hospital, Chinese PLA Institute of Nephrology, State Key Laboratory of Kidney Diseases, National Clinical Research Center for Kidney Diseases, Beijing 100853, China
- Department of Nephrology, Beijing Changping Hospital, Beijing 102200, China
| | - Guang-Yan Cai
- Department of Nephrology, Chinese PLA General Hospital, Chinese PLA Institute of Nephrology, State Key Laboratory of Kidney Diseases, National Clinical Research Center for Kidney Diseases, Beijing 100853, China
| | - Xiang-Mei Chen
- Department of Nephrology, Chinese PLA General Hospital, Chinese PLA Institute of Nephrology, State Key Laboratory of Kidney Diseases, National Clinical Research Center for Kidney Diseases, Beijing 100853, China
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32
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Zinellu A, Sotgia S, Sotgiu E, Assaretti S, Baralla A, Mangoni AA, Satta AE, Carru C. Cholesterol lowering treatment restores blood global DNA methylation in chronic kidney disease (CKD) patients. Nutr Metab Cardiovasc Dis 2017; 27:822-829. [PMID: 28755807 DOI: 10.1016/j.numecd.2017.06.011] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/03/2017] [Revised: 06/19/2017] [Accepted: 06/19/2017] [Indexed: 12/14/2022]
Abstract
BACKGROUND AND AIMS Chronic kidney disease (CKD) is characterized by increased oxidative stress (OS). In consideration of the well-known link between OS and DNA methylation we assessed DNA methylcytosine (mCyt) concentrations in CKD patients at baseline and during cholesterol lowering treatment. METHODS AND RESULTS DNA methylation and OS indices (malonyldialdehyde, MDA; allantoin/uric acid ratio, All/UA) were measured in 30 CKD patients randomized to three cholesterol lowering regimens for 12 months (simvastatin 40 mg/day, ezetimibe/simvastatin 10/20 mg/day, or ezetimibe/simvastatin 10/40 mg/day) and 30 age- and sex-matched healthy controls. DNA methylation was significantly lower in CKD patients vs. controls (4.06 ± 0.20% vs. 4.27 ± 0.17% mCyt, p = 0.0001). Treatment significantly increased mCyt DNA concentrations in all patients (4.06 ± 0.04% at baseline; 4.12 ± 0.03% at 4 months; 4.17 ± 0.03% at 8 months; and 4.20 ± 0.02% at 12 months, p = 0.0001 for trend). A trend for a greater effect on DNA methylation was observed with combined treatment ezetimibe/simvastatin 10/40 mg/day (+5.2% after one year treatment). The treatment-associated mCyt increase was significantly correlated with the concomitant reduction in MDA concentrations and All/AU ratios. CONCLUSION Our results demonstrate that CKD patients have a lower degree of DNA methylation and that cholesterol lowering treatment restores mCyt DNA concentrations to levels similar to healthy controls. The treatment-associated increase in DNA methylation is correlated with a concomitant reduction in OS markers. The study was registered at clinicaltrials.gov (NCT00861731).
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Affiliation(s)
- A Zinellu
- Department of Biomedical Sciences, University of Sassari, Sassari, Italy.
| | - S Sotgia
- Department of Biomedical Sciences, University of Sassari, Sassari, Italy
| | - E Sotgiu
- Department of Biomedical Sciences, University of Sassari, Sassari, Italy
| | - S Assaretti
- Department of Biomedical Sciences, University of Sassari, Sassari, Italy
| | - A Baralla
- Department of Biomedical Sciences, University of Sassari, Sassari, Italy
| | - A A Mangoni
- Department of Clinical Pharmacology, School of Medicine, Flinders University, Adelaide, Australia
| | - A E Satta
- Department of Surgical, Microsurgical and Medical Sciences, University of Sassari, Sassari, Italy
| | - C Carru
- Department of Biomedical Sciences, University of Sassari, Sassari, Italy; Quality Control Unit, University Hospital Sassari (AOU), Sassari, Italy
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33
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Neyra JA, Hu MC. Potential application of klotho in human chronic kidney disease. Bone 2017; 100:41-49. [PMID: 28115282 PMCID: PMC5474175 DOI: 10.1016/j.bone.2017.01.017] [Citation(s) in RCA: 82] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/01/2016] [Revised: 01/18/2017] [Accepted: 01/18/2017] [Indexed: 01/13/2023]
Abstract
The extracellular domain of transmembrane alpha-Klotho (αKlotho, hereinafter simply called Klotho) is cleaved by secretases and released into the circulation as soluble Klotho. Soluble Klotho in the circulation starts to decline early in chronic kidney disease (CKD) stage 2 and urinary Klotho possibly even earlier in CKD stage 1. Therefore soluble Klotho could serve as an early and sensitive marker of kidney function decline. Moreover, preclinical animal data support Klotho deficiency is not just merely a biomarker, but a pathogenic factor for CKD progression and extrarenal CKD complications including cardiovascular disease and disturbed mineral metabolism. Prevention of Klotho decline, re-activation of endogenous Klotho production or supplementation of exogenous Klotho are all associated with attenuation of renal fibrosis, retardation of CKD progression, improvement of mineral metabolism, amelioration of cardiomyopathy, and alleviation of vascular calcification in CKD. Therefore Klotho is not only a diagnostic and/or prognostic marker for CKD, but the treatment of Klotho deficiency may be a promising strategy to prevent, retard, and decrease the burden of comorbidity in CKD.
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Affiliation(s)
- Javier A Neyra
- Department of Internal Medicine, University of Texas Southwestern Medical Center, USA; Charles and Jane Pak Center for Mineral Metabolism and Clinical Research, University of Texas Southwestern Medical Center, USA
| | - Ming Chang Hu
- Department of Internal Medicine, University of Texas Southwestern Medical Center, USA; Charles and Jane Pak Center for Mineral Metabolism and Clinical Research, University of Texas Southwestern Medical Center, USA.
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34
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Current epigenetic aspects the clinical kidney researcher should embrace. Clin Sci (Lond) 2017; 131:1649-1667. [DOI: 10.1042/cs20160596] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2016] [Revised: 04/17/2017] [Accepted: 04/19/2017] [Indexed: 02/06/2023]
Abstract
Chronic kidney disease (CKD), affecting 10–12% of the world’s adult population, is associated with a considerably elevated risk of serious comorbidities, in particular, premature vascular disease and death. Although a wide spectrum of causative factors has been identified and/or suggested, there is still a large gap of knowledge regarding the underlying mechanisms and the complexity of the CKD phenotype. Epigenetic factors, which calibrate the genetic code, are emerging as important players in the CKD-associated pathophysiology. In this article, we review some of the current knowledge on epigenetic modifications and aspects on their role in the perturbed uraemic milieu, as well as the prospect of applying epigenotype-based diagnostics and preventive and therapeutic tools of clinical relevance to CKD patients. The practical realization of such a paradigm will require that researchers apply a holistic approach, including the full spectrum of the epigenetic landscape as well as the variability between and within tissues in the uraemic milieu.
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35
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Shiels PG, McGuinness D, Eriksson M, Kooman JP, Stenvinkel P. The role of epigenetics in renal ageing. Nat Rev Nephrol 2017. [PMID: 28626222 DOI: 10.1038/nrneph.2017.78] [Citation(s) in RCA: 76] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
An ability to separate natural ageing processes from processes specific to morbidities is required to understand the heterogeneity of age-related organ dysfunction. Mechanistic insight into how epigenetic factors regulate ageing throughout the life course, linked to a decline in renal function with ageing, is already proving to be of value in the analyses of clinical and epidemiological cohorts. Noncoding RNAs provide epigenetic regulatory circuits within the kidney, which reciprocally interact with DNA methylation processes, histone modification and chromatin. These interactions have been demonstrated to reflect the biological age and function of renal allografts. Epigenetic factors control gene expression and activity in response to environmental perturbations. They also have roles in highly conserved signalling pathways that modulate ageing, including the mTOR and insulin/insulin-like growth factor signalling pathways, and regulation of sirtuin activity. Nutrition, the gut microbiota, inflammation and environmental factors, including psychosocial and lifestyle stresses, provide potential mechanistic links between the epigenetic landscape of ageing and renal dysfunction. Approaches to modify the renal epigenome via nutritional intervention, targeting the methylome or targeting chromatin seem eminently feasible, although caution is merited owing to the potential for intergenerational and transgenerational effects.
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Affiliation(s)
- Paul G Shiels
- Section of Epigenetics, Institute of Cancer Sciences, Wolfson Wohl Translational Research Centre, University of Glasgow, Garscube Estate, Switchback Road, Bearsden, Glasgow G61 1QH, UK
| | - Dagmara McGuinness
- Section of Epigenetics, Institute of Cancer Sciences, Wolfson Wohl Translational Research Centre, University of Glasgow, Garscube Estate, Switchback Road, Bearsden, Glasgow G61 1QH, UK
| | - Maria Eriksson
- Department of Biosciences and Nutrition (BioNut), H2, Eriksson, Novum 141, 83 Huddinge, Sweden
| | - Jeroen P Kooman
- Department of Internal Medicine, Division of Nephrology, Maastricht University Medical Center, PO Box 5800, 6202 AZ Maastrich, Netherlands
| | - Peter Stenvinkel
- Division of Renal Medicine, Department of Clinical Science, Intervention and Technology, Karolinska University Hospital, Huddinge, Karolinska Institutet, SE-14157 Stockholm, Sweden
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36
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Yin S, Zhang Q, Yang J, Lin W, Li Y, Chen F, Cao W. TGFβ-incurred epigenetic aberrations of miRNA and DNA methyltransferase suppress Klotho and potentiate renal fibrosis. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2017; 1864:1207-1216. [PMID: 28285987 DOI: 10.1016/j.bbamcr.2017.03.002] [Citation(s) in RCA: 58] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/08/2016] [Revised: 03/03/2017] [Accepted: 03/06/2017] [Indexed: 12/31/2022]
Abstract
Renal fibrosis is a common pathological feature of chronic kidney diseases (CKD) and its development and progression are significantly affected by epigenetic modifications such as aberrant miRNA and DNA methylation. Klotho is an anti-aging and anti-fibrotic protein and its early decline after renal injury is reportedly associated with aberrant DNA methylation. However, the key upstream pathological mediators and the molecular cascade leading to epigenetic Klotho suppression are not exclusively established. Here we investigate the epigenetic mechanism of Klotho deficiency and its functional relevance in renal fibrogenesis. Fibrotic kidneys induced by unilateral ureteral occlusion (UUO) displayed marked Klotho suppression and the promoter hypermethylation. These abnormalities were likely due to deregulated transforming growth factor-beta (TGFβ) since TGFβ alone caused the similar epigenetic aberrations in cultured renal cells and TGFβ blockade prevented the alterations in UUO kidney. Further investigation revealed that TGFβ enhanced DNA methyltransferase (DNMT) 1 and DNMT3a via inhibiting miR-152 and miR-30a in both renal cells and fibrotic kidneys. Accordingly the blockade of either TGFβ signaling or DNMT1/3a activities significantly recovered the Klotho loss and attenuated pro-fibrotic protein expression and renal fibrosis. Moreover, Klotho knockdown by RNA interferences abolished the anti-fibrotic effects of DNMT inhibition in both TGFβ-treated renal cell and UUO kidney, indicating that TGFβ-mediated miR-152/30a inhibitions, DNMT1/3a aberrations and subsequent Klotho loss constitute a critical regulatory loop that eliminates Klotho's anti-fibrotic activities and potentiates renal fibrogenesis. Thus, our study elaborates a novel epigenetic cascade of renal fibrogenesis and reveals the potential therapeutic targets for treating the renal fibrosis-associated kidney diseases.
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Affiliation(s)
- Shasha Yin
- Nanjing University School of Medicine, Jiangsu, Key Laboratory of Molecular Medicine, Nanjing 210093, China
| | - Qin Zhang
- Nanjing University School of Medicine, Jiangsu, Key Laboratory of Molecular Medicine, Nanjing 210093, China
| | - Jun Yang
- Nanjing University School of Medicine, Jiangsu, Key Laboratory of Molecular Medicine, Nanjing 210093, China
| | - Wenjun Lin
- Nanjing University School of Medicine, Jiangsu, Key Laboratory of Molecular Medicine, Nanjing 210093, China
| | - Yanning Li
- Nanjing University School of Medicine, Jiangsu, Key Laboratory of Molecular Medicine, Nanjing 210093, China
| | - Fang Chen
- Nanjing University School of Medicine, Jiangsu, Key Laboratory of Molecular Medicine, Nanjing 210093, China
| | - Wangsen Cao
- Nanjing University School of Medicine, Jiangsu, Key Laboratory of Molecular Medicine, Nanjing 210093, China.
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37
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Sun L, Zou LX, Chen MJ. Make Precision Medicine Work for Chronic Kidney Disease. Med Princ Pract 2017; 26:101-107. [PMID: 28152529 PMCID: PMC5588375 DOI: 10.1159/000455101] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/07/2016] [Accepted: 12/13/2016] [Indexed: 02/03/2023] Open
Abstract
Precision medicine is based on accurate diagnosis and tailored intervention through the use of omics and clinical data together with epidemiology and environmental exposures. Precision medicine should be achieved with minimum adverse events and maximum efficacy in patients with chronic kidney disease (CKD). In this review, the breakthroughs of omics in CKD and the application of systems biology are reviewed. The potential role of transforming growth factor-β1 in the targeted intervention of renal fibrosis is discussed as an example of how to make precision medicine work for CKD.
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Affiliation(s)
- Ling Sun
- *Ling Sun, Department of Nephrology, Xuzhou Central Hospital, Medical College of Southeast University, Xuzhou City, Jiangsu Province (China), E-Mail
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38
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Lu X, Hu MC. Klotho/FGF23 Axis in Chronic Kidney Disease and Cardiovascular Disease. KIDNEY DISEASES 2016; 3:15-23. [PMID: 28785560 DOI: 10.1159/000452880] [Citation(s) in RCA: 123] [Impact Index Per Article: 15.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/01/2016] [Accepted: 10/26/2016] [Indexed: 12/26/2022]
Abstract
BACKGROUND Membrane αKlotho (hereinafter called Klotho) is highly expressed in the kidney and functions as a coreceptor of FGF receptors (FGFRs) to activate specific fibroblast growth factor 23 (FGF23) signal pathway. FGF23 is produced in bones and participates in the maintenance of mineral homeostasis. The extracellular domain of transmembrane Klotho can be cleaved by secretases and released into the circulation as soluble Klotho. Soluble Klotho does not only weakly activate FGFRs to transduce the FGF23 signaling pathway, but also functions as an enzyme and hormonal substance to play a variety of biological functions. FGF23 exerts its biological effects through activation of FGFRs in a Klotho-dependent manner. However, extremely high FGF23 can exert its pathological action in a Klotho-independent manner. SUMMARY The decline in serum and urinary Klotho followed by a rise in serum FGF23 at an early stage of chronic kidney disease (CKD) functions as an early biomarker for kidney dysfunction and can also serve as a predictor for risk of cardiovascular disease (CVD) and mortality in both CKD patients and the general population. Moreover, Klotho deficiency is a pathogenic factor for CKD progression and CVD. FGF23 may also contribute to CVD. Prevention of Klotho decline, reactivation of endogenous Klotho production, or supplementation of exogenous Klotho attenuate renal fibrosis, retard CKD progression, improve mineral metabolism, ameliorate cardiomyopathy, and alleviate vascular calcification in CKD. However, the poor CVD outcome after depletion of FGF23 with FGF23 antibody stimulates the generation of a more specific inhibitor of FGF23 for CKD treatment. KEY MESSAGE Klotho/FGF23 may not only be diagnostic and/or prognostic biomarkers for CKD and CVD, but are also pathogenic contributors to CKD progression and CVD development. The Klotho/FGF23 axis should be a novel target for renal clinics.
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Affiliation(s)
- Xiang Lu
- Department of Geriatrics, Sir Run Run Hospital, Nanjing Medical University, Nanjing, PR China
| | - Ming Chang Hu
- Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX, USA.,Department of Pediatrics, University of Texas Southwestern Medical Center, Dallas, TX, USA.,Department of Charles and Jane Pak Center for Mineral Metabolism and Clinical Research, University of Texas Southwestern Medical Center, Dallas, TX, USA
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39
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Zhang Q, Yin S, Liu L, Liu Z, Cao W. Rhein reversal of DNA hypermethylation-associated Klotho suppression ameliorates renal fibrosis in mice. Sci Rep 2016; 6:34597. [PMID: 27703201 PMCID: PMC5050540 DOI: 10.1038/srep34597] [Citation(s) in RCA: 44] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2016] [Accepted: 09/15/2016] [Indexed: 11/15/2022] Open
Abstract
Renal fibrosis is the hallmark of chronic kidney diseases (CKD) and its development and progression are significantly affected by epigenetic modifications. Rhein, a plant-derived anthraquinone, displays strong anti-fibrosis properties, but its protective mode of action remains incompletely understood. Here we explore the mechanism of Rhein anti-renal fibrosis by investigating its regulation of Klotho, a known renal anti-fibrotic protein whose suppression after renal injury reportedly involves aberrant DNA methylation. We report that Rhein is an impressive up-regulator of Klotho and it markedly reversed Klotho down-regulation in unilateral ureteral occlusion-induced fibrotic kidney. Further examinations revealed that Klotho loss in fibrotic kidney is associated with Klotho promoter hypermethylation due to aberrant methyltransferase 1 and 3a expressions. However, Rhein significantly corrected all these epigenetic alterations and subsequently alleviated pro-fibrotic protein expression and renal fibrosis, whereas Klotho knockdown via RNA interferences largely abrogated the anti-renal fibrotic effects of Rhein, suggesting that Rhein epigenetic reversal of Klotho loss represents a critical mode of action that confers Rhein’s anti- renal fibrotic functions. Altogether our studies uncover a novel hypomethylating character of Rhein in preventing Klotho loss and renal fibrosis, and demonstrate the efficacy of Klotho-targeted epigenetic intervention in potential treatment of renal fibrosis-associated kidney diseases.
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Affiliation(s)
- Qin Zhang
- Division of Nephrology, Jinling Hospital, Southern Medical University, Nanjing, 210016, China.,National Clinical Research Center of Kidney Diseases, Jinling Hospital, Nanjing University School of Medicine, Nanjing, 210016, China
| | - Shasha Yin
- The Key lab of Jiangsu molecular Medicine, Nanjing University School of Medicine, Nanjing, 210093, China
| | - Lin Liu
- National Clinical Research Center of Kidney Diseases, Jinling Hospital, Nanjing University School of Medicine, Nanjing, 210016, China
| | - Zhihong Liu
- Division of Nephrology, Jinling Hospital, Southern Medical University, Nanjing, 210016, China.,National Clinical Research Center of Kidney Diseases, Jinling Hospital, Nanjing University School of Medicine, Nanjing, 210016, China
| | - Wangsen Cao
- National Clinical Research Center of Kidney Diseases, Jinling Hospital, Nanjing University School of Medicine, Nanjing, 210016, China.,The Key lab of Jiangsu molecular Medicine, Nanjing University School of Medicine, Nanjing, 210093, China
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40
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Zhang Q, Liu L, Lin W, Yin S, Duan A, Liu Z, Cao W. Rhein reverses Klotho repression via promoter demethylation and protects against kidney and bone injuries in mice with chronic kidney disease. Kidney Int 2016; 91:144-156. [PMID: 27692562 DOI: 10.1016/j.kint.2016.07.040] [Citation(s) in RCA: 91] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2016] [Revised: 07/19/2016] [Accepted: 07/28/2016] [Indexed: 12/26/2022]
Abstract
Rhein is an anthraquinone compound isolated from the medicinal plant rhubarb and mainly used in the clinical treatment of diabetic nephropathy. Rhein exhibits various renoprotective functions, but the underlying mechanisms are not fully determined. However, its renoprotective properties recapitulate the role of Klotho, a renal-specific antiaging protein critical for maintaining kidney homeostasis. Here we explored the connections between rhein renoprotection and Klotho in a mouse model of adenine-induced chronic kidney disease. In addition to being an impressive Klotho upregulator, rhein remarkably reversed renal Klotho deficiency in adenine-treated mice. This effect was associated with significant improvement in disturbed serum biochemistry, profibrogenic protein expression, and kidney and bone damage. Further investigation of the molecular basis of Klotho loss revealed that these kidneys displayed marked inductions of DNA methyltransferase DNMT1/DNMT3a and Klotho promoter hypermethylation, whereas rhein treatment effectively corrected these alterations. The renal protective effects of rhein were largely abolished when Klotho was knocked-down by RNA interferences, suggesting that rhein reversal of Klotho deficiency is essential for its renoprotective actions. Thus, our study clarifies how rhein regulation of Klotho expression contributes to its renoprotection and brings new insights into Klotho-targeted strategy for the treatment of kidney diseases of various etiologies.
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Affiliation(s)
- Qin Zhang
- National Clinical Research Center of Kidney Diseases, Jinling Hospital, Nanjing University School of Medicine, Nanjing, China; The Key Lab of Jiangsu Molecular Medicine, Nanjing University School of Medicine, Nanjing, China; Division of Nephrology, Jinling Hospital, Southern Medical University, Nanjing, China
| | - Lin Liu
- National Clinical Research Center of Kidney Diseases, Jinling Hospital, Nanjing University School of Medicine, Nanjing, China
| | - Wenjun Lin
- National Clinical Research Center of Kidney Diseases, Jinling Hospital, Nanjing University School of Medicine, Nanjing, China
| | - Shasha Yin
- The Key Lab of Jiangsu Molecular Medicine, Nanjing University School of Medicine, Nanjing, China
| | - Aiping Duan
- National Clinical Research Center of Kidney Diseases, Jinling Hospital, Nanjing University School of Medicine, Nanjing, China
| | - Zhihong Liu
- National Clinical Research Center of Kidney Diseases, Jinling Hospital, Nanjing University School of Medicine, Nanjing, China; Division of Nephrology, Jinling Hospital, Southern Medical University, Nanjing, China.
| | - Wangsen Cao
- National Clinical Research Center of Kidney Diseases, Jinling Hospital, Nanjing University School of Medicine, Nanjing, China; The Key Lab of Jiangsu Molecular Medicine, Nanjing University School of Medicine, Nanjing, China.
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Abstract
Alpha-Klotho (αKlotho) protein is encoded by the gene, Klotho, and functions as a coreceptor for endocrine fibroblast growth factor-23. The extracellular domain of αKlotho is cleaved by secretases and released into the circulation where it is called soluble αKlotho. Soluble αKlotho in the circulation starts to decline in chronic kidney disease (CKD) stage 2 and urinary αKlotho in even earlier CKD stage 1. Therefore soluble αKlotho is an early and sensitive marker of decline in kidney function. Preclinical data from numerous animal experiments support αKlotho deficiency as a pathogenic factor for CKD progression and extrarenal CKD complications including cardiac and vascular disease, hyperparathyroidism, and disturbed mineral metabolism. αKlotho deficiency induces cell senescence and renders cells susceptible to apoptosis induced by a variety of cellular insults including oxidative stress. αKlotho deficiency also leads to defective autophagy and angiogenesis and promotes fibrosis in the kidney and heart. Most importantly, prevention of αKlotho decline, upregulation of endogenous αKlotho production, or direct supplementation of soluble αKlotho are all associated with attenuation of renal fibrosis, retardation of CKD progression, improvement of mineral metabolism, amelioration of cardiac function and morphometry, and alleviation of vascular calcification in CKD. Therefore in rodents, αKlotho is not only a diagnostic and prognostic marker for CKD but the enhancement of endogenous or supplement of exogenous αKlotho are promising therapeutic strategies to prevent, retard, and decrease the comorbidity burden of CKD.
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Affiliation(s)
- J A Neyra
- University of Texas Southwestern Medical Center, Dallas, TX, United States; Charles and Jane Pak Center for Mineral Metabolism and Clinical Research, University of Texas Southwestern Medical Center, Dallas, TX, United States
| | - M C Hu
- University of Texas Southwestern Medical Center, Dallas, TX, United States; Charles and Jane Pak Center for Mineral Metabolism and Clinical Research, University of Texas Southwestern Medical Center, Dallas, TX, United States.
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Buendía P, Ramírez R, Aljama P, Carracedo J. Klotho Prevents Translocation of NFκB. VITAMINS AND HORMONES 2016; 101:119-50. [PMID: 27125740 DOI: 10.1016/bs.vh.2016.02.005] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Klotho protein is a β-glucuronidase capable of hydrolyzing steroid β-glucuronides. Two molecules are produced by the Klotho gene, a membrane bound form and a circulating form. This protein is recognized as an antiaging gene with pleiotropic functions. The activation of cellular systems is associated with the pathogenesis of several chronic and degenerative diseases associated with an inflammatory state. Inflammation is characterized by an activation of NFκB. Klotho suppresses nuclear factor NFκB activation and the subsequent transcription of proinflammatory genes. This review focuses on the current understanding of Klotho protein function and its relationship with NFκB regulation, emphasizing its potential involvement in the pathophysiologic process.
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Affiliation(s)
- P Buendía
- Instituto Maimónides de Investigación Biomédica de Córdoba (IMIBIC), Universidad de Córdoba/Hospital Universitario Reina Sofía, Córdoba, Spain
| | - R Ramírez
- Alcalá de Henares University, Madrid, Spain
| | - P Aljama
- Instituto Maimónides de Investigación Biomédica de Córdoba (IMIBIC), Universidad de Córdoba/Hospital Universitario Reina Sofía, Córdoba, Spain
| | - J Carracedo
- Instituto Maimónides de Investigación Biomédica de Córdoba (IMIBIC), Universidad de Córdoba/Hospital Universitario Reina Sofía, Córdoba, Spain.
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Shiao CC, Wu PC, Huang TM, Lai TS, Yang WS, Wu CH, Lai CF, Wu VC, Chu TS, Wu KD. Long-term remote organ consequences following acute kidney injury. CRITICAL CARE : THE OFFICIAL JOURNAL OF THE CRITICAL CARE FORUM 2015; 19:438. [PMID: 26707802 PMCID: PMC4699348 DOI: 10.1186/s13054-015-1149-5] [Citation(s) in RCA: 48] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Acute kidney injury (AKI) has been a global health epidemic problem with soaring incidence, increased long-term risks for multiple comorbidities and mortality, as well as elevated medical costs. Despite the improvement of patient outcomes following the advancements in preventive and therapeutic strategies, the mortality rates among critically ill patients with AKI remain as high as 40–60 %. The distant organ injury, a direct consequence of deleterious systemic effects, following AKI is an important explanation for this phenomenon. To date, most evidence of remote organ injury in AKI is obtained from animal models. Whereas the observations in humans are from a limited number of participants in a relatively short follow-up period, or just focusing on the cytokine levels rather than clinical solid outcomes. The remote organ injury is caused with four underlying mechanisms: (1) “classical” pattern of acute uremic state; (2) inflammatory nature of the injured kidneys; (3) modulating effect of AKI of the underlying disease process; and (4) healthcare dilemma. While cytokines/chemokines, leukocyte extravasation, oxidative stress, and certain channel dysregulation are the pathways involving in the remote organ damage. In the current review, we summarized the data from experimental studies to clinical outcome studies in the field of organ crosstalk following AKI. Further, the long-term consequences of distant organ-system, including liver, heart, brain, lung, gut, bone, immune system, and malignancy following AKI with temporary dialysis were reviewed and discussed.
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Affiliation(s)
- Chih-Chung Shiao
- Division of Nephrology, Department of Internal Medicine, Saint Mary's Hospital Luodong, 160 Chong-Cheng South Road, Luodong, Yilan, 265, Taiwan.,Saint Mary's Medicine, Nursing and Management College, 160 Chong-Cheng South Road, Luodong, Yilan, 265, Taiwan
| | - Pei-Chen Wu
- Division of Nephrology, Department of Internal Medicine, MacKay Memorial Hospital, 92, Sec. 2, Zhongshan N. Road, Taipei, 10449, Taiwan
| | - Tao-Min Huang
- Division of Nephrology, Department of Internal Medicine, National Taiwan University Hospital Yun-Lin Branch, 579, Sec. 2, Yunlin Road, Douliu City, Yunlin County, 640, Taiwan
| | - Tai-Shuan Lai
- Department of Internal Medicine, National Taiwan University Hospital, Bei-Hu Branch, 87 Neijiang Street, Taipei, 108, Taiwan
| | - Wei-Shun Yang
- Division of Nephrology, Department of Internal Medicine, National Taiwan University Hospital, Hisn-Chu Branch, No.25, Lane 442, Sec. 1, Jingguo Road, Hsin-Chu City, 300, Taiwan
| | - Che-Hsiung Wu
- Division of Nephrology, Taipei Tzu Chi Hospital, Buddhist Tzu Chi Medical Foundation, Taipei, Taiwan.,School of Medicine, Tzu Chi University, Hualien, Taiwan
| | - Chun-Fu Lai
- Division of Nephrology, Department of Internal Medicine, National Taiwan University Hospital, 7 Chung-Shan South Road, Zhong-Zheng District, Taipei, 100, Taiwan
| | - Vin-Cent Wu
- Division of Nephrology, Department of Internal Medicine, National Taiwan University Hospital, 7 Chung-Shan South Road, Zhong-Zheng District, Taipei, 100, Taiwan.
| | - Tzong-Shinn Chu
- Division of Nephrology, Department of Internal Medicine, National Taiwan University Hospital, 7 Chung-Shan South Road, Zhong-Zheng District, Taipei, 100, Taiwan
| | - Kwan-Dun Wu
- Division of Nephrology, Department of Internal Medicine, National Taiwan University Hospital, 7 Chung-Shan South Road, Zhong-Zheng District, Taipei, 100, Taiwan
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Activation of AMP-Activated Protein Kinase by Adenine Alleviates TNF-Alpha-Induced Inflammation in Human Umbilical Vein Endothelial Cells. PLoS One 2015; 10:e0142283. [PMID: 26544976 PMCID: PMC4636334 DOI: 10.1371/journal.pone.0142283] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2015] [Accepted: 10/20/2015] [Indexed: 12/28/2022] Open
Abstract
The AMP-activated protein kinase (AMPK) signaling system plays a key role in cellular stress by repressing the inflammatory responses induced by the nuclear factor-kappa B (NF-κB) system. Previous studies suggest that the anti-inflammatory role of AMPK involves activation by adenine, but the mechanism that allows adenine to produce these effects has not yet been elucidated. In human umbilical vein endothelial cells (HUVECs), adenine was observed to induce the phosphorylation of AMPK in both a time- and dose-dependent manner as well as its downstream target acetyl Co-A carboxylase (ACC). Adenine also attenuated NF-κB targeting of gene expression in a dose-dependent manner and decreased monocyte adhesion to HUVECs following tumor necrosis factor (TNF-α) treatment. The short hairpin RNA (shRNA) against AMPK α1 in HUVECs attenuated the adenine-induced inhibition of NF-κB activation in response to TNF-α, thereby suggesting that the anti-inflammatory role of adenine is mediated by AMPK. Following the knockdown of adenosyl phosphoribosyl transferase (APRT) in HUVECs, adenine supplementation failed to induce the phosphorylation of AMPK and ACC. Similarly, the expression of a shRNA against APRT nullified the anti-inflammatory effects of adenine in HUVECs. These results suggested that the role of adenine as an AMPK activator is related to catabolism by APRT, which increases the cellular AMP levels to activate AMPK.
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Klinger M, Banasik M. Immunological characteristics of the elderly allograft recipient. Transplant Rev (Orlando) 2015; 29:219-23. [DOI: 10.1016/j.trre.2015.07.002] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2015] [Revised: 06/28/2015] [Accepted: 07/28/2015] [Indexed: 01/24/2023]
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Felsenfeld AJ, Levine BS, Rodriguez M. Pathophysiology of Calcium, Phosphorus, and Magnesium Dysregulation in Chronic Kidney Disease. Semin Dial 2015; 28:564-77. [DOI: 10.1111/sdi.12411] [Citation(s) in RCA: 89] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Affiliation(s)
- Arnold J. Felsenfeld
- Department of Medicine; VA Greater Los Angeles Healthcare System and the David Geffen School of Medicine at UCLA; Los Angeles California
| | - Barton S. Levine
- Department of Medicine; VA Greater Los Angeles Healthcare System and the David Geffen School of Medicine at UCLA; Los Angeles California
| | - Mariano Rodriguez
- Nephrology Service; IMIBIC; Hospital Universitario Reina Sofia; University of Cordoba; Cordoba Spain
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47
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Olauson H, Vervloet MG, Cozzolino M, Massy ZA, Ureña Torres P, Larsson TE. New insights into the FGF23-Klotho axis. Semin Nephrol 2015; 34:586-97. [PMID: 25498378 DOI: 10.1016/j.semnephrol.2014.09.005] [Citation(s) in RCA: 62] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Abnormal mineral metabolism is a hallmark in patients with advanced chronic kidney disease (CKD). Hyperphosphatemia, and the homeostatic mechanisms controlling phosphate metabolism, have received particular attention over the past decade. The phosphate-regulating hormone fibroblast growth factor-23 (FGF23) was discovered through studies of rare hypophosphatemic disorders, whereas Klotho, which subsequently turned out to be a co-receptor for FGF23, was identified in a mouse model showing hyperphosphatemia and multiple aging-like traits. The FGF23-Klotho endocrine axis is a pivotal regulator of mineral metabolism. In CKD, early onset of Klotho deficiency contributes to renal FGF23 resistance and a maladaptive increase in circulating FGF23. FGF23 is an early biomarker of renal injury and increased FGF23 predicts adverse clinical outcomes, in particular cardiovascular disease. A paradigm of FGF23 excess and Klotho deficiency is proposed, in which FGF23 preferentially stimulates left ventricular hypertrophy, and loss of Klotho augments fibrosis, endothelial dysfunction, and vascular calcification. The clinical benefit of FGF23 and Klotho measurements remain uncertain, nevertheless, the FGF23-Klotho axis is a solid candidate for a novel diagnostic and therapeutic target in CKD.
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Affiliation(s)
- Hannes Olauson
- Division of Renal Medicine, Department of Clinical Science, Intervention and Technology, Karolinska Institutet, Stockholm, Sweden
| | - Marc G Vervloet
- Department of Nephrology, Institute for Cardiovascular Research, VU University Medical Center, Amsterdam, The Netherlands
| | - Mario Cozzolino
- Department of Health Sciences, University of Milan, Renal Division, San Paolo Hospital, Milan, Italy
| | - Ziad A Massy
- Inserm U-1088, Université de Picardie Jules Verne (UPJV), Amiens, France; Division of Nephrology, Ambroise Paré Hospital, Paris-Ile-de-France-Ouest University (Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)), Paris-Boulogne Billancourt, France
| | - Pablo Ureña Torres
- Service of Nephrology and Dialysis, Clinique du Landy and Department of Renal Physiology, Necker Hospital, University of Paris Descartes, Paris, France
| | - Tobias E Larsson
- Division of Renal Medicine, Department of Clinical Science, Intervention and Technology, Karolinska Institutet, Stockholm, Sweden; Department of Nephrology, Karolinska University Hospital, Stockholm, Sweden.
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48
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Abstract
The discovery of the Klotho (KL) gene, which was originally identified as a putative aging-suppressor gene, has generated tremendous interest and has advanced understanding of the aging process. In mice, the overexpression of the KL gene extends the life span, whereas mutations to the KL gene shorten the life span. The human KL gene encodes the α-Klotho protein, which is a multifunctional protein that regulates the metabolism of phosphate, calcium, and vitamin D. α-Klotho also may function as a hormone, although the α-Klotho receptor(s) has not been found. Point mutations of the KL gene in humans are associated with hypertension and kidney disease, which suggests that α-Klotho may be essential to the maintenance of normal renal function. Three α-Klotho protein types with potentially different functions have been identified: a full-length transmembrane α-Klotho, a truncated soluble α-Klotho, and a secreted α-Klotho. Recent evidence suggests that α-Klotho suppresses the insulin and Wnt signaling pathways, inhibits oxidative stress, and regulates phosphatase and calcium absorption. In this review, we provide an update on recent advances in the understanding of the molecular, genetic, biochemical, and physiological properties of the KL gene. Specifically, this review focuses on the structure of the KL gene and the factors that regulate KL gene transcription, the key sites in the regulation of α-Klotho enzyme activity, the α-Klotho signaling pathways, and the molecular mechanisms that underlie α-Klotho function. This current understanding of the molecular biology of the α-Klotho protein may offer new insights into its function and role in aging.
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Affiliation(s)
- Yuechi Xu
- Department of Physiology, College of Medicine, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma 73104
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Young GH, Lin JT, Cheng YF, Huang CF, Chao CY, Nong JY, Chen PK, Chen HM. Identification of adenine modulating AMPK activation in NIH/3T3 cells by proteomic approach. J Proteomics 2015; 120:204-14. [DOI: 10.1016/j.jprot.2015.03.012] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2015] [Revised: 02/28/2015] [Accepted: 03/12/2015] [Indexed: 02/08/2023]
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50
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Meijers RWJ, Betjes MGH, Baan CC, Litjens NHR. T-cell ageing in end-stage renal disease patients: Assessment and clinical relevance. World J Nephrol 2014; 3:268-276. [PMID: 25374821 PMCID: PMC4220360 DOI: 10.5527/wjn.v3.i4.268] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/10/2014] [Revised: 07/08/2014] [Accepted: 08/31/2014] [Indexed: 02/06/2023] Open
Abstract
End-stage renal disease (ESRD) patients have a defective T-cell-mediated immune system which is related to excessive premature ageing of the T-cell compartment. This is likely to be caused by the uremia-associated pro-inflammatory milieu, created by loss of renal function. Therefore, ESRD patients are highly susceptible for infections, have an increased risk for virus-associated cancers, respond poorly to vaccination and have an increased risk for atherosclerotic diseases. Three ageing parameters can be used to assess an immunological T-cell age. First, thymic output can be determined by assessing the T-cell receptor excision circles-content together with CD31 expression within the naïve T cells. Second, the telomere length of T cells and third the T-cell differentiation status are also indicators of T-cell ageing. Analyses based on these parameters in ESRD patients revealed that the immunological T-cell age is increased by on average 20 years compared to the chronological age. After kidney transplantation (KTx) the aged T-cell phenotype persists although the pro-inflammatory milieu is diminished. This might be explained by epigenetic modifications at hematopoietic stem cells level. Assessment of an immunological T-cell age could be an important tool to identify KTx recipients who are at risk for allograft rejection or to prevent over-immunosuppression.
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