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Sheikh IA, Midura-Kiela MT, Herchuelz A, Sokolow S, Kiela PR, Ghishan FK. The Na +/Ca 2+ exchanger NCX3 mediates Ca 2+ entry into matrix vesicles to facilitate initial steps of mineralization in osteoblasts. J Extracell Vesicles 2024; 13:e12450. [PMID: 38859730 DOI: 10.1002/jev2.12450] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2023] [Revised: 02/23/2024] [Accepted: 04/24/2024] [Indexed: 06/12/2024] Open
Abstract
Matrix vesicles (MVs) provide the initial site for amorphous hydroxyapatite (HA) formation within mineralizing osteoblasts. Although Na+/Ca2+ exchanger isoform-3 (NCX3, SLC8A3) was presumed to function as major Ca2+ transporter responsible for Ca2+ extrusion out of osteoblast into the calcifying bone matrix, its presence and functional role in MVs have not been investigated. In this study, we investigated the involvement of NCX3 in MV-mediated mineralization process and its impact on bone formation. Using differentiated MC3T3-E1 cells, we demonstrated that NCX3 knockout in these cells resulted in a significant reduction of Ca2+ deposition due to reduced Ca2+ entry within the MVs, leading to impaired mineralization. Consequently, the capacity of MVs to promote extracellular HA formation was diminished. Moreover, primary osteoblast isolated from NCX3 deficient mice (NCX3-/-) exhibits reduced mineralization efficacy without any effect on osteoclast activity. To validate this in vitro finding, μCT analysis revealed a substantial decrease in trabecular bone mineral density in both genders of NCX3-/- mice, thus supporting the critical role of NCX3 in facilitating Ca2+ uptake into the MVs to initiate osteoblast-mediated mineralization. NCX3 expression was also found to be the target of downregulation by inflammatory mediators in vitro and in vivo. This newfound understanding of NCX3's functional role in MVs opens new avenues for therapeutic interventions aimed at enhancing bone mineralization and treating mineralization-related disorders.
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Affiliation(s)
- Irshad A Sheikh
- Daniel Cracchiolo Institute for Pediatric Autoimmune Disease Research, Steele Children's Research Center, Department of Pediatrics, University of Arizona, Tucson, Arizona, USA
| | - Monica T Midura-Kiela
- Daniel Cracchiolo Institute for Pediatric Autoimmune Disease Research, Steele Children's Research Center, Department of Pediatrics, University of Arizona, Tucson, Arizona, USA
| | - André Herchuelz
- Laboratoire de Pharmacodynamie et de Thérapeutique, Faculté de Médecine, Université Libre de Bruxelles, Bruxelles, Belgium
| | - Sophie Sokolow
- School of Nursing, University of California, Los Angeles (UCLA), Los Angeles, California, USA
| | - Pawel R Kiela
- Daniel Cracchiolo Institute for Pediatric Autoimmune Disease Research, Steele Children's Research Center, Department of Pediatrics, University of Arizona, Tucson, Arizona, USA
- Department of Immunobiology, University of Arizona, Tucson, Arizona, USA
| | - Fayez K Ghishan
- Daniel Cracchiolo Institute for Pediatric Autoimmune Disease Research, Steele Children's Research Center, Department of Pediatrics, University of Arizona, Tucson, Arizona, USA
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2
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Lee H, Jeon JH, Kim ES. Mitochondrial dysfunctions in T cells: focus on inflammatory bowel disease. Front Immunol 2023; 14:1219422. [PMID: 37809060 PMCID: PMC10556505 DOI: 10.3389/fimmu.2023.1219422] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2023] [Accepted: 09/06/2023] [Indexed: 10/10/2023] Open
Abstract
Mitochondria has emerged as a critical ruler of metabolic reprogramming in immune responses and inflammation. In the context of colitogenic T cells and IBD, there has been increasing research interest in the metabolic pathways of glycolysis, pyruvate oxidation, and glutaminolysis. These pathways have been shown to play a crucial role in the metabolic reprogramming of colitogenic T cells, leading to increased inflammatory cytokine production and tissue damage. In addition to metabolic reprogramming, mitochondrial dysfunction has also been implicated in the pathogenesis of IBD. Studies have shown that colitogenic T cells exhibit impaired mitochondrial respiration, elevated levels of mROS, alterations in calcium homeostasis, impaired mitochondrial biogenesis, and aberrant mitochondria-associated membrane formation. Here, we discuss our current knowledge of the metabolic reprogramming and mitochondrial dysfunctions in colitogenic T cells, as well as the potential therapeutic applications for treating IBD with evidence from animal experiments.
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Affiliation(s)
- Hoyul Lee
- Research Institute of Aging and Metabolism, Kyungpook National University, Daegu, Republic of Korea
| | - Jae-Han Jeon
- Research Institute of Aging and Metabolism, Kyungpook National University, Daegu, Republic of Korea
- Department of Internal Medicine, School of Medicine, Kyungpook National University, Kyungpook National University Chilgok Hospital, Daegu, Republic of Korea
| | - Eun Soo Kim
- Division of Gastroenterology, Department of Internal Medicine, Kyungpook National University, Kyungpook National University Hospital, Daegu, Republic of Korea
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3
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Luo ZH, Ma JX, Zhang W, Tian AX, Gong SW, Li Y, Lai YX, Ma XL. Alterations in the microenvironment and the effects produced of TRPV5 in osteoporosis. J Transl Med 2023; 21:327. [PMID: 37198647 DOI: 10.1186/s12967-023-04182-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2022] [Accepted: 05/05/2023] [Indexed: 05/19/2023] Open
Abstract
The pathogenesis of osteoporosis involves multiple factors, among which alterations in the bone microenvironment play a crucial role in disrupting normal bone metabolic balance. Transient receptor potential vanilloid 5 (TRPV5), a member of the TRPV family, is an essential determinant of the bone microenvironment, acting at multiple levels to influence its properties. TRPV5 exerts a pivotal influence on bone through the regulation of calcium reabsorption and transportation while also responding to steroid hormones and agonists. Although the metabolic consequences of osteoporosis, such as loss of bone calcium, reduced mineralization capacity, and active osteoclasts, have received significant attention, this review focuses on the changes in the osteoporotic microenvironment and the specific effects of TRPV5 at various levels.
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Affiliation(s)
- Zhi-Heng Luo
- Tianjin Hospital, Tianjin University, Jie Fang Nan Road 406, Tianjin, 300211, People's Republic of China
- Tianjin Key Laboratory of Orthopedic Biomechanics and Medical Engineering, Tianjin Hospital, Tianjin, 300050, People's Republic of China
| | - Jian-Xiong Ma
- Tianjin Hospital, Tianjin University, Jie Fang Nan Road 406, Tianjin, 300211, People's Republic of China
- Tianjin Key Laboratory of Orthopedic Biomechanics and Medical Engineering, Tianjin Hospital, Tianjin, 300050, People's Republic of China
| | - Wei Zhang
- Centre for Translational Medicine Research & Development, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, 1068 Xue Yuan Avenue, Shenzhen University Town, Shenzhen, 518055, Guangdong, People's Republic of China
| | - Ai-Xian Tian
- Tianjin Hospital, Tianjin University, Jie Fang Nan Road 406, Tianjin, 300211, People's Republic of China
- Tianjin Key Laboratory of Orthopedic Biomechanics and Medical Engineering, Tianjin Hospital, Tianjin, 300050, People's Republic of China
| | - Shu-Wei Gong
- Tianjin Hospital, Tianjin University, Jie Fang Nan Road 406, Tianjin, 300211, People's Republic of China
- Tianjin Key Laboratory of Orthopedic Biomechanics and Medical Engineering, Tianjin Hospital, Tianjin, 300050, People's Republic of China
| | - Yan Li
- Tianjin Hospital, Tianjin University, Jie Fang Nan Road 406, Tianjin, 300211, People's Republic of China
- Tianjin Key Laboratory of Orthopedic Biomechanics and Medical Engineering, Tianjin Hospital, Tianjin, 300050, People's Republic of China
| | - Yu-Xiao Lai
- Centre for Translational Medicine Research & Development, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, 1068 Xue Yuan Avenue, Shenzhen University Town, Shenzhen, 518055, Guangdong, People's Republic of China.
| | - Xin-Long Ma
- Tianjin Hospital, Tianjin University, Jie Fang Nan Road 406, Tianjin, 300211, People's Republic of China.
- Tianjin Key Laboratory of Orthopedic Biomechanics and Medical Engineering, Tianjin Hospital, Tianjin, 300050, People's Republic of China.
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4
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Chen C, Xie C, Xiong Y, Wu H, Wu L, Zhu J, Xing C, Mao H. Damage of uremic myocardium by p-cresyl sulfate and the ameliorative effect of Klotho by regulating SIRT6 ubiquitination. Toxicol Lett 2022; 367:19-31. [PMID: 35839976 DOI: 10.1016/j.toxlet.2022.06.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2022] [Revised: 06/01/2022] [Accepted: 06/20/2022] [Indexed: 11/15/2022]
Abstract
Uremic cardiomyopathy (UCM) is a common complication in patients with chronic kidney disease (CKD) and an important risk factor for death. P-Cresyl sulfate (PCS) is a damaging factor in UCM, and Klotho is a protective factor. However, the molecular mechanisms of Klotho and PCS in UCM and the relationship between PCS and Klotho are unclear. In vitro, Klotho treatment inhibited PCS-induced cardiomyocyte hypertrophy and apoptosis by blocking mTOR phosphorylation and inhibiting DNA double-strand breaks (DSBs), respectively. Moreover, PCS increased SIRT6 protein ubiquitination and downregulated SIRT6 protein expression, while Klotho inhibited SIRT6 protein ubiquitination and upregulated SIRT6 protein expression. In a mouse model of 5/6 nephrectomy (5/6Nx)-induced UCM, the expression of Klotho in the kidney and serum was decreased, and the expression of SIRT6 protein in myocardial tissues was lower. PCS further reduced Klotho and SIRT6 expression, aggravated heart structure and function abnormalities, and increased myocardial cell apoptosis in UCM mice. Administration of Klotho protein inhibited the downregulation of SIRT6 protein expression and improved cardiac structure and function. Furthermore, serum PCS level was associated with the left ventricular mass (LVM) and left ventricular mass index (LVMI) in hemodialysis patients. In conclusion, the uremic toxin PCS injures cardiomyocytes via mTOR phosphorylation and DSBs, and Klotho antagonizes the damaging effects of PCS. Moreover, the SIRT6 protein plays an important role in UCM, and Klotho suppresses SIRT6 ubiquitination induced by PCS, further improves cardiac structure and function in UCM and exerts protective effects.
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Affiliation(s)
- Cheng Chen
- Department of Nephrology, Jiangsu Province Hospital, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China,; Department of Medical Science, Yangzhou Polytechnic College, Yangzhou, China
| | - Caidie Xie
- Department of Nephrology, Jiangsu Province Hospital, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China,; Department of Nephrology, Nanjing Second Hospital, Nanjing Hospital Affiliated to Nanjing University of Traditional Chinese Medicine, Nanjing, China
| | - Yiqing Xiong
- Department of Nephrology, Jiangsu Province Hospital, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China
| | - Hanzhang Wu
- Department of Nephrology, Jiangsu Province Hospital, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China
| | - Lin Wu
- Department of Nephrology, Jiangsu Province Hospital, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China
| | - Jingfeng Zhu
- Department of Nephrology, Jiangsu Province Hospital, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China
| | - Changying Xing
- Department of Nephrology, Jiangsu Province Hospital, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China,.
| | - Huijuan Mao
- Department of Nephrology, Jiangsu Province Hospital, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China,.
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5
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Peek CT, Ford CA, Eichelberger KR, Jacobse J, Torres TP, Maseda D, Latour YL, Piazuelo MB, Johnson JR, Byndloss MX, Wilson KT, Rathmell JC, Goettel JA, Cassat JE. Intestinal Inflammation Promotes MDL-1 + Osteoclast Precursor Expansion to Trigger Osteoclastogenesis and Bone Loss. Cell Mol Gastroenterol Hepatol 2022; 14:731-750. [PMID: 35835390 PMCID: PMC9420375 DOI: 10.1016/j.jcmgh.2022.07.002] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/26/2022] [Revised: 07/01/2022] [Accepted: 07/05/2022] [Indexed: 12/13/2022]
Abstract
BACKGROUND & AIMS Inflammatory bowel disease (IBD) is characterized by severe gastrointestinal inflammation, but many patients experience extra-intestinal disease. Bone loss is one common extra-intestinal manifestation of IBD that occurs through dysregulated interactions between osteoclasts and osteoblasts. Systemic inflammation has been postulated to contribute to bone loss, but the specific pathologic mechanisms have not yet been fully elucidated. We hypothesized that intestinal inflammation leads to bone loss through increased abundance and altered function of osteoclast progenitors. METHODS We used chemical, T cell driven, and infectious models of intestinal inflammation to determine the impact of intestinal inflammation on bone volume, the skeletal cytokine environment, and the cellular changes to pre-osteoclast populations within bone marrow. Additionally, we evaluated the potential for monoclonal antibody treatment against an inflammation-induced osteoclast co-receptor, myeloid DNAX activation protein 12-associating lectin-1 (MDL-1) to reduce bone loss during colitis. RESULTS We observed significant bone loss across all models of intestinal inflammation. Bone loss was associated with an increase in pro-osteoclastogenic cytokines within the bone and an expansion of a specific Cd11b-/loLy6Chi osteoclast precursor (OCP) population. Intestinal inflammation led to altered OCP expression of surface receptors involved in osteoclast differentiation and function, including the pro-osteoclastogenic co-receptor MDL-1. OCPs isolated from mice with intestinal inflammation demonstrated enhanced osteoclast differentiation ex vivo compared to controls, which was abrogated by anti-MDL-1 antibody treatment. Importantly, in vivo anti-MDL-1 antibody treatment ameliorated bone loss during intestinal inflammation. CONCLUSIONS Collectively, these data implicate the pathologic expansion and altered function of OCPs expressing MDL-1 in bone loss during IBD.
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Affiliation(s)
- Christopher T. Peek
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee
| | - Caleb A. Ford
- Department of Biomedical Engineering, Vanderbilt University, Nashville, Tennessee
| | - Kara R. Eichelberger
- Department of Pediatrics, Division of Pediatric Infectious Diseases, Vanderbilt University Medical Center, Nashville, Tennessee
| | - Justin Jacobse
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee,Division of Gastroenterology, Hepatology, and Nutrition, Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee
| | - Teresa P. Torres
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee
| | - Damian Maseda
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee,Department of Dermatology, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Yvonne L. Latour
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee
| | - M. Blanca Piazuelo
- Division of Gastroenterology, Hepatology, and Nutrition, Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee,Center for Mucosal Inflammation and Cancer, Vanderbilt University Medical Center, Nashville, Tennessee
| | - Joshua R. Johnson
- Vanderbilt Center for Bone Biology, Vanderbilt University Medical Center, Nashville, Tennessee
| | - Mariana X. Byndloss
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee,Vanderbilt Institute for Infection, Immunology, and Inflammation, Vanderbilt University Medical Center, Nashville, Tennessee
| | - Keith T. Wilson
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee,Division of Gastroenterology, Hepatology, and Nutrition, Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee,Vanderbilt Institute for Infection, Immunology, and Inflammation, Vanderbilt University Medical Center, Nashville, Tennessee,Center for Mucosal Inflammation and Cancer, Vanderbilt University Medical Center, Nashville, Tennessee,Veterans Affairs Tennessee Valley Healthcare System, Nashville, Tennessee
| | - Jeffrey C. Rathmell
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee,Vanderbilt Institute for Infection, Immunology, and Inflammation, Vanderbilt University Medical Center, Nashville, Tennessee,Center for Mucosal Inflammation and Cancer, Vanderbilt University Medical Center, Nashville, Tennessee,Vanderbilt Center for Immunobiology, Vanderbilt University Medical Center, Nashville, Tennessee
| | - Jeremy A. Goettel
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee,Division of Gastroenterology, Hepatology, and Nutrition, Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee,Vanderbilt Institute for Infection, Immunology, and Inflammation, Vanderbilt University Medical Center, Nashville, Tennessee,Center for Mucosal Inflammation and Cancer, Vanderbilt University Medical Center, Nashville, Tennessee
| | - James E. Cassat
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee,Department of Biomedical Engineering, Vanderbilt University, Nashville, Tennessee,Department of Pediatrics, Division of Pediatric Infectious Diseases, Vanderbilt University Medical Center, Nashville, Tennessee,Vanderbilt Institute for Infection, Immunology, and Inflammation, Vanderbilt University Medical Center, Nashville, Tennessee,Center for Mucosal Inflammation and Cancer, Vanderbilt University Medical Center, Nashville, Tennessee,Vanderbilt Center for Immunobiology, Vanderbilt University Medical Center, Nashville, Tennessee,Vanderbilt Center for Bone Biology, Vanderbilt University Medical Center, Nashville, Tennessee,Correspondence Address correspondence to: Dr Jim Cassat, Division of Pediatric Infectious Diseases, Department of Pediatrics, Vanderbilt University Medical Center, 1035 Light Hall, 2215-B Garland Ave, Nashville, TN, 37232. tel: (615) 936-6494.
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6
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Rajput S, Mehta P, Mittal M, Rajender S, Chattopadhyay N. Human Relevance of Preclinical Studies on the Skeletal Impact of Inflammatory Bowel Disease: A Systematic Review and Meta-Analysis. Calcif Tissue Int 2021; 108:708-724. [PMID: 33558960 DOI: 10.1007/s00223-021-00808-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/08/2020] [Accepted: 01/12/2021] [Indexed: 01/02/2023]
Abstract
Inflammatory bowel disease (IBD) is a relapsing chronic idiopathic inflammatory condition. The increased risks of fractures in the spine and decreased BMD at all weight-bearing skeletal sites have been reported in IBD patients. The understanding of the mechanisms of IBD-induced bone loss is far from complete. Appropriate animal models are a prerequisite for studying IBD-induced bone loss, which prompted us to undertake quantitative meta-analyses by pooling data from the available IBD models that assessed various bone parameters. Sufficient data for meta-analysis are obtained from chemically- but not genetically induced models. Among the chemically induced models, only the effects of dextran sulfate sodium (DSS) and 2,4,6-trinitrobenzene sulfonic acid (TNBS) on bone parameters have been reported. Meta-analysis showed that both DSS (Hedge's g = 2.124, p = 0.001) and TNBS (Hedge's g = 6.292, p = 0.000) increased inflammatory disease severity. In pooled analysis, bone volumes in femur (Hedge's g = - 3.42, p = 0.000) and tibia (Hedge's g = - 2.49, p = 0.000) showed significant losses upon DSS administration. Similarly, bone formation rate was significantly reduced upon IBD induction (Hedge's g = - 3.495, p = 0.006). Besides, cortical thickness was reduced and trabecular microstructure deteriorated by IBD induction. Insufficient data precluded us from determining the effect of IBD on bone strength and calciotropic hormones, as well as the impact of proinflammatory cytokines on bone turnover. This meta-analysis showed that IBD induction in rodents causes significant bone loss. Impaired osteoblast function appears to be the cause of this impact.
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Affiliation(s)
- Swati Rajput
- Division of Endocrinology and Centre for Research in Anabolic Skeletal Targets in Health and Illness (ASTHI), CSIR-Central Drug Research Institute, Sector 10, Jankipuram Extension, Sitapur Road, Lucknow, 226031, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, India
| | - Poonam Mehta
- Division of Endocrinology and Centre for Research in Anabolic Skeletal Targets in Health and Illness (ASTHI), CSIR-Central Drug Research Institute, Sector 10, Jankipuram Extension, Sitapur Road, Lucknow, 226031, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, India
| | - Monika Mittal
- Division of Endocrinology and Centre for Research in Anabolic Skeletal Targets in Health and Illness (ASTHI), CSIR-Central Drug Research Institute, Sector 10, Jankipuram Extension, Sitapur Road, Lucknow, 226031, India
| | - Singh Rajender
- Division of Endocrinology and Centre for Research in Anabolic Skeletal Targets in Health and Illness (ASTHI), CSIR-Central Drug Research Institute, Sector 10, Jankipuram Extension, Sitapur Road, Lucknow, 226031, India.
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, India.
| | - Naibedya Chattopadhyay
- Division of Endocrinology and Centre for Research in Anabolic Skeletal Targets in Health and Illness (ASTHI), CSIR-Central Drug Research Institute, Sector 10, Jankipuram Extension, Sitapur Road, Lucknow, 226031, India.
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, India.
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Rondanelli M, Lamburghini S, Faliva MA, Peroni G, Riva A, Allegrini P, Spadaccini D, Gasparri C, Iannello G, Infantino V, Alalwan TA, Perna S, Miccono A. A food pyramid, based on a review of the emerging literature, for subjects with inflammatory bowel disease. ACTA ACUST UNITED AC 2020; 68:17-46. [PMID: 32499202 DOI: 10.1016/j.endinu.2020.01.004] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2019] [Revised: 12/14/2019] [Accepted: 01/08/2020] [Indexed: 02/07/2023]
Abstract
Emerging literature suggests that diet plays an important modulatory role in inflammatory bowel disease (IBD) through the management of inflammation and oxidative stress. The aim of this narrative review is to evaluate the evidence collected up till now regarding optimum diet therapy for IBD and to design a food pyramid for these patients. The pyramid shows that carbohydrates should be consumed every day (3 portions), together with tolerated fruits and vegetables (5 portions), yogurt (125ml), and extra virgin olive oil; weekly, fish (4 portions), white meat (3 portions), eggs (3 portions), pureed legumes (2 portions), seasoned cheeses (2 portions), and red or processed meats (once a week). At the top of the pyramid, there are two pennants: the red one means that subjects with IBD need some personalized supplementation and the black one means that there are some foods that are banned. The food pyramid makes it easier for patients to decide what they should eat.
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Affiliation(s)
- Mariangela Rondanelli
- IRCCS Mondino Foundation, Pavia, Department of Public Health, Experimental and Forensic Medicine, Unit of Human and Clinical Nutrition, University of Pavia, Pavia 27100, Italy
| | - Silvia Lamburghini
- University of Pavia, Department of Public Health, Experimental and Forensic Medicine, Section of Human Nutrition, Endocrinology and Nutrition Unit, Azienda di Servizi alla Persona, Pavia 27100, Italy
| | - Milena A Faliva
- University of Pavia, Department of Public Health, Experimental and Forensic Medicine, Section of Human Nutrition, Endocrinology and Nutrition Unit, Azienda di Servizi alla Persona, Pavia 27100, Italy
| | - Gabriella Peroni
- University of Pavia, Department of Public Health, Experimental and Forensic Medicine, Section of Human Nutrition, Endocrinology and Nutrition Unit, Azienda di Servizi alla Persona, Pavia 27100, Italy
| | - Antonella Riva
- Research and Development Unit, Indena, Milan 20146, Italy
| | | | - Daniele Spadaccini
- University of Pavia, Department of Public Health, Experimental and Forensic Medicine, Section of Human Nutrition, Endocrinology and Nutrition Unit, Azienda di Servizi alla Persona, Pavia 27100, Italy
| | - Clara Gasparri
- University of Pavia, Department of Public Health, Experimental and Forensic Medicine, Section of Human Nutrition, Endocrinology and Nutrition Unit, Azienda di Servizi alla Persona, Pavia 27100, Italy
| | - Giancarlo Iannello
- General Management, Azienda di Servizi alla Persona "Istituto Santa Margherita", Pavia 27100, Italy
| | - Vittoria Infantino
- University of Bari Aldo Moro, Department of Biomedical Science and Human Oncology, Section of Human Nutrition, Endocrinology and Nutrition Unit, Azienda di Servizi alla Persona, Pavia 27100, Italy.
| | - Tariq A Alalwan
- Department of Biology, College of Science, University of Bahrain, Sakhir Campus, P.O. Box 32038, Bahrain
| | - Simone Perna
- Department of Biology, College of Science, University of Bahrain, Sakhir Campus, P.O. Box 32038, Bahrain
| | - Alessandra Miccono
- University of Pavia, Department of Public Health, Experimental and Forensic Medicine, Section of Human Nutrition, Endocrinology and Nutrition Unit, Azienda di Servizi alla Persona, Pavia 27100, Italy
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8
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TRPV Subfamily (TRPV2, TRPV3, TRPV4, TRPV5, and TRPV6) Gene and Protein Expression in Patients with Ulcerative Colitis. J Immunol Res 2020; 2020:2906845. [PMID: 32455137 PMCID: PMC7231094 DOI: 10.1155/2020/2906845] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2019] [Revised: 03/04/2020] [Accepted: 04/11/2020] [Indexed: 12/22/2022] Open
Abstract
Introduction TRPVs are a group of receptors with a channel activity predominantly permeable to Ca2+. This subfamily is involved in the development of gastrointestinal diseases such as ulcerative colitis (UC). The aim of the study was to characterize the gene and protein expression of the TRPV subfamily in UC patients and controls. Methods We determined by quantitative PCR the gene expression of TRPV2, TRPV3, TRPV4, TRPV5, and TRPV6 in 45 UC patients (29 active UC and 16 remission UC) and 26 noninflamed controls. Protein expression was evaluated in 5 μm thick sections of formalin-fixed, paraffin-embedded tissue from 5 customized severe active UC patients and 5 control surgical specimens. Results TRPV2 gene expression was increased in the control group compared with active UC and remission patients (P = 0.002 and P = 0.05, respectively). TRPV3 gene expression was significantly higher in controls than in active UC patients (P = 0.002). The gene expression of TRPV4 was significantly higher in colonic tissue from patients with remission UC compared with active UC patients (P = 0.05) and controls (P = 0.005). TRPV5 had significantly higher mRNA levels in a control group compared with active UC patients (P = 0.02). The gene expression of TRPV6 was significantly higher in the colonic tissue from patients with active UC compared with the control group (P = 0.05). The protein expression of TRPV2 was upregulated in the mucosa and submucosa from the controls compared with the UC patients (P ≤ 0.003). The protein expression of TRPV3 and TRPV4 was upregulated in all intestinal layers from the controls compared with the UC patients (P < 0.001). TRPV5 was upregulated in the submucosa and serosa from the controls vs. UC patients (P < 0.001). TRPV6 was upregulated in all intestinal layers from the UC patients vs. controls (P ≤ 0.001). Conclusion The TRPV subfamily clearly showed a differential expression in the UC patients compared with the controls, suggesting their role in the pathophysiology of UC.
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9
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Mechanisms Underlying Bone Loss Associated with Gut Inflammation. Int J Mol Sci 2019; 20:ijms20246323. [PMID: 31847438 PMCID: PMC6940820 DOI: 10.3390/ijms20246323] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2019] [Revised: 11/29/2019] [Accepted: 12/10/2019] [Indexed: 12/11/2022] Open
Abstract
Patients with gastrointestinal diseases frequently suffer from skeletal abnormality, characterized by reduced bone mineral density, increased fracture risk, and/or joint inflammation. This pathological process is characterized by altered immune cell activity and elevated inflammatory cytokines in the bone marrow microenvironment due to disrupted gut immune response. Gastrointestinal disease is recognized as an immune malfunction driven by multiple factors, including cytokines and signaling molecules. However, the mechanism by which intestinal inflammation magnified by gut-residing actors stimulates bone loss remains to be elucidated. In this article, we discuss the main risk factors potentially contributing to intestinal disease-associated bone loss, and summarize current animal models, illustrating gut-bone axis to bridge the gap between intestinal inflammation and skeletal disease.
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10
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Cherng JH, Hsu YJ, Liu CC, Tang SH, Sartika D, Chang SJ, Fan GY, Wu ST, Meng E. Activities of Ca 2+-related ion channels during the formation of kidney stones in an infection-induced urolithiasis rat model. Am J Physiol Renal Physiol 2019; 317:F1342-F1349. [PMID: 31509008 DOI: 10.1152/ajprenal.00199.2019] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
Bacterial infection has long been recognized to contribute to struvite urinary stone deposition; however, its contribution to the development of chronic kidney stones has not been extensively investigated. In the present study, we hypothesized another possible method of bacteria contributing to the formation of calcium oxalate (CaOx) that accounts for the biggest part of the kidney stone. Bacteria may play important roles by influencing renal Ca2+-related ion channel activities, resulting in chronic inflammation of the kidney along with rapid aggregation of stones. We examined the correlation among infection-promoted CaOx kidney stones and alterations in Ca2+-related ion channels in an animal model with experimentally induced Proteus mirabilis and foreign body infection. After the bladder was infected for 7 days, the data demonstrated that stones were presented and induced severe renal tubular breakage as well as altered levels of monocyte chemoattractant protein-1, cyclooxygenase-2, osteopontin, and transient receptor potential vanilloid member 5 expression, reflecting responses of kidney ion channels. Monocyte chemoattractant protein-1, osteopontin, and transient receptor potential vanilloid member 5 expression was significantly downregulated over time, indicating the chronic inflammation phase of the kidney and accelerated aggregation of CaOx crystals, respectively, whereas cyclooxygenase-2 exhibited no differences. These results indicated that bacterial infection is considerably correlated with an alteration in renal Ca2+-related ion channels and might support specific and targeted Ca2+-related ion channel-based therapeutics for urolithiasis and related inflammatory renal damage.
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Affiliation(s)
- Juin-Hong Cherng
- Department and Graduate Institute of Biology and Anatomy, National Defense Medical Center, Taipei, Taiwan, Republic of China.,Department of Gerontological Health Care, National Taipei University of Nursing and Health Sciences, Taipei, Taiwan, Republic of China
| | - Yu-Juei Hsu
- Division of Nephrology, Department of Medicine, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan, Republic of China
| | - Chuan-Chieh Liu
- Department of Cardiology, Cardinal Tien Hospital, Taipei, Taiwan, Republic of China
| | - Shou-Hung Tang
- Division of Urology, Department of Surgery, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan, Republic of China
| | - Dewi Sartika
- Department and Graduate Institute of Biology and Anatomy, National Defense Medical Center, Taipei, Taiwan, Republic of China
| | - Shu-Jen Chang
- Division of Rheumatology/Immunology/Allergy, Department of Internal Medicine, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan, Republic of China
| | - Gang-Yi Fan
- Graduate Institute of Medical Sciences, National Defense Medical Center, Taipei, Taiwan, Republic of China
| | - Sheng-Tang Wu
- Division of Urology, Department of Surgery, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan, Republic of China
| | - En Meng
- Division of Urology, Department of Surgery, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan, Republic of China
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11
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Pawlak D, Domaniewski T, Znorko B, Pawlak K. The use of LP533401 as a therapeutic option for renal osteodystrophy affects, renal calcium handling, vitamin D metabolism, and bone health in uremic rats. Expert Opin Ther Targets 2019; 23:353-364. [PMID: 30801205 DOI: 10.1080/14728222.2019.1586883] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
BACKGROUND Klotho is a key regulator of phosphate and Ca2+-transport in the kidney. Recently, we showed that treatment with LP533401 improved bone health in rats with chronic kidney disease (CKD) via the normalization of serum phosphate resulting from the reduced renal expression of phosphate cotransporters, including Klotho. METHODS We evaluated the effect of LP533401 therapy on Klotho-expression-dependent Ca2+-transporters, renal calcium handling, and the potential consequences for the bone of uremic rats. RESULTS Treatment with LP533401 and its vehicle resulted in the inhibition of transient receptor potential vanilloid receptor subtypes 5 and 6 (TRPV5, TRPV6) and calbindin (CaBP-28k, CaBP-9k) expression. The compensatory acceleration in renal expression of Na+/Ca2+-exchanger, 25-hydroxyvitamin d-1α-hydroxylase (CYP27B1), the intensification of vitamin D metabolism, and disruption of sophisticated balance between 1,25-dihydroxyvitamin D-serotonin was observed, especially in rats treated with LP533401. The imbalance between 1,25-dihydroxyvitamin D-serotonin levels led to intensified bone remodeling and improvement in bone geometry, mineral status, and strength in animals treated with LP533401. CONCLUSION The modulation of circulating serotonin and its relation to other regulators of calcium handling can play an important role in calcium homeostasis and bone integrity in CKD rats treated with LP533401.
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Affiliation(s)
- Dariusz Pawlak
- a Department of Pharmacodynamics , Medical University of Bialystok , Bialystok , Poland
| | - Tomasz Domaniewski
- b Department of Monitored Pharmacotherapy , Medical University of Bialystok , Bialystok , Poland
| | - Beata Znorko
- b Department of Monitored Pharmacotherapy , Medical University of Bialystok , Bialystok , Poland
| | - Krystyna Pawlak
- b Department of Monitored Pharmacotherapy , Medical University of Bialystok , Bialystok , Poland
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12
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Renal ischemia-reperfusion injury impairs renal calcium, magnesium, and phosphate handling in mice. Pflugers Arch 2019; 471:901-914. [PMID: 30685787 DOI: 10.1007/s00424-019-02255-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2018] [Revised: 01/04/2019] [Accepted: 01/10/2019] [Indexed: 01/04/2023]
Abstract
Fibroblast growth factor 23 (FGF23) levels are elevated in patients with acute kidney injury (AKI). The consequences on renal Ca2+, Mg2+, and Pi regulatory mechanisms are unknown. We hypothesized that renal ischemia-reperfusion (I/R) injury alters the expression of important renal Ca2+, Mg2+, and Pi transport proteins. I/R injury was induced in male C57BL/6 mice by clamping both renal arteries for 27 min. Mice were investigated 18 h later. The mRNA and protein levels of renal Ca2+, Mg2+, and Pi transport proteins were measured by RT-qPCR and western blot analysis. I/R injury-induced hyperphosphatemia and hypermagnesemia were paralleled by a decrease in glomerular filtration rate and an increase in the fractional excretion of Ca2+, Mg2+, and Pi. I/R injury affected the fibroblast growth factor 23 (FGF23)-klotho-vitamin D axis by increasing plasma levels of FGF23 and downregulation of renal klotho expression. Plasma levels of PTH and 1,25-dihydroxyvitamin D3 were unchanged. Further, downregulation of key genes for paracellular reabsorption of Ca2+ and Mg2+ (claudin (Cldn)2, Cldn10b, Cldn16, Cldn19) and for active transcellular transport of Ca2+, Mg2+, and Pi (calbindin-D28K, Ncx1, Pmca4, Cnnm2, Trpm7, NaPi-2a, and NaPi-2c) was observed. However, renal expression of Trpv5 and Trpv6 was increased. In vitro studies support a direct effect of proinflammatory cytokines on the mRNA expression of Cldn16, Cldn19, and Trpv6. Our findings indicate that renal I/R injury increases FGF23 blood levels independent of PTH and 1,25-dihydroxyvitamin D3. This increase is associated with hypermagnesemia, hyperphosphatemia, and increased or decreased expression of specific renal Ca2+, Mg2+, and Pi transporters, respectively.
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13
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Meurer M, Höcherl K. Endotoxaemia differentially regulates the expression of renal Ca 2+ transport proteins in mice. Acta Physiol (Oxf) 2019; 225:e13175. [PMID: 30133162 DOI: 10.1111/apha.13175] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2017] [Revised: 08/17/2018] [Accepted: 08/18/2018] [Indexed: 12/16/2022]
Abstract
AIM Alterations in parathyroid hormone (PTH) and/or vitamin D signalling are frequently reported in patients with sepsis. The consequences on renal and intestinal Ca2+ and Pi regulatory mechanisms are still unclear. We hypothesized that endotoxaemia alters the expression of important renal and intestinal Ca2+ and Pi transport proteins. METHODS Male C57BL/6 mice were treated with lipopolysaccharide (LPS; 3 mg/kg; i.p.). The mRNA and protein levels of renal and intestinal Ca2+ and Pi transport proteins were measured by RT-qPCR, immunohistochemistry and western blot analysis. RESULTS Lipopolysaccharide-induced hypocalcaemia and hyperphosphataemia was paralleled by a decrease in glomerular filtration rate and urinary excretion of Ca2+ and Pi . Endotoxaemia augmented plasma levels of PTH and affected the fibroblast growth factor 23 (FGF23)-klotho-vitamin D axis by increasing plasma levels of FGF23 and downregulation of renal klotho expression. Renal expression of CYP27b1 and plasma levels of 1,25-dihydroxyvitamin D3 were increased in response to LPS. Endotoxaemia augmented the renal expression of TRPV5, TRPV6 and PiT1, whereas the renal expression of calbindin-D28K , NCX1, NaPi -2a and NaPi -2c were decreased. Incubation of primary distal tubule cells with LPS increased TRPV6 mRNA levels. Furthermore, LPS decreased the intestinal expression of TRPV6, calbindin-D9K and of NaPi -2b. CONCLUSION Our findings indicate that endotoxaemia is associated with hypocalcaemia and hyperphosphataemia and a disturbed FGF23-klotho-vitamin D signaling. Further, LPS-induced acute kidney injury was accompanied by an increased or decreased expression of specific renal and intestinal Ca2+ and Pi transporters respectively. It seems unlikely that LPS-induced hypocalcaemia is due to renal loss of Ca2+ .
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Affiliation(s)
- Manuel Meurer
- Institute of Experimental and Clinical Pharmacology and Toxicology; Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU); Erlangen Germany
| | - Klaus Höcherl
- Institute of Experimental and Clinical Pharmacology and Toxicology; Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU); Erlangen Germany
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14
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Olesen CW, Vogensen J, Axholm I, Severin M, Schnipper J, Pedersen IS, von Stemann JH, Schrøder JM, Christensen DP, Pedersen SF. Trafficking, localization and degradation of the Na +,HCO 3- co-transporter NBCn1 in kidney and breast epithelial cells. Sci Rep 2018; 8:7435. [PMID: 29743600 PMCID: PMC5943355 DOI: 10.1038/s41598-018-25059-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2017] [Accepted: 04/13/2018] [Indexed: 01/28/2023] Open
Abstract
The Na+;HCO3− co-transporter NBCn1 (SLC4A7) is a major regulator of intracellular pH yet its trafficking and turnover are essentially unstudied. Here, we used MDCK-II and MCF-7 cells to investigate these processes in epithelial cells. GFP-NBCn1 membrane localization was abolished by truncation of the full NBCn1 C-terminal tail (C-tail) yet did not require the C-terminal PDZ-binding motif (ETSL). Glutathione-S-Transferase-pulldown of the C-tail followed by mass spectrometry analysis revealed putative interactions with multiple sorting-, degradation- and retention factors, including the scaffolding protein RACK1. Pulldown of FLAG-tagged deletion constructs mapped the RACK1 interaction to the proximal NBCn1 C-tail. Proximity Ligation Assay and co-immunoprecipitation confirmed that native NBCn1 interacts with RACK1 in a cellular context. Consistent with a functional role of this complex, RACK1 knockdown reduced NBCn1 membrane localization without affecting total NBCn1 expression. Notably, only non-confluent cells exhibited detectable NBCn1-RACK1 plasma membrane co-localization, suggesting that RACK1 regulates the trafficking of NBCn1 to the membrane. Whereas total NBCn1 degradation was slow, with a half-life of more than 24 h, one-third of surface NBCn1 was constitutively endocytosed from the basolateral membrane within 60 min. This suggests that a fraction of NBCn1 exhibits recycling between the basolateral membrane and intracellular compartment(s). Our findings have important implications for understanding NBCn1 regulation as well as its dysregulation in disease.
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Affiliation(s)
- Christina Wilkens Olesen
- Section for Cell Biology and Physiology, Department of Biology, University of Copenhagen, Universitetsparken 13, DK-2100, Copenhagen Ø, Denmark
| | - Jens Vogensen
- Section for Cell Biology and Physiology, Department of Biology, University of Copenhagen, Universitetsparken 13, DK-2100, Copenhagen Ø, Denmark
| | - Ida Axholm
- Section for Cell Biology and Physiology, Department of Biology, University of Copenhagen, Universitetsparken 13, DK-2100, Copenhagen Ø, Denmark
| | - Marc Severin
- Section for Cell Biology and Physiology, Department of Biology, University of Copenhagen, Universitetsparken 13, DK-2100, Copenhagen Ø, Denmark
| | - Julie Schnipper
- Section for Cell Biology and Physiology, Department of Biology, University of Copenhagen, Universitetsparken 13, DK-2100, Copenhagen Ø, Denmark
| | - Isabella Skandorff Pedersen
- Section for Cell Biology and Physiology, Department of Biology, University of Copenhagen, Universitetsparken 13, DK-2100, Copenhagen Ø, Denmark
| | - Jakob Hjorth von Stemann
- Section for Cell Biology and Physiology, Department of Biology, University of Copenhagen, Universitetsparken 13, DK-2100, Copenhagen Ø, Denmark
| | - Jacob Morville Schrøder
- Section for Cell Biology and Physiology, Department of Biology, University of Copenhagen, Universitetsparken 13, DK-2100, Copenhagen Ø, Denmark
| | - Dan Ploug Christensen
- Section for Cell Biology and Physiology, Department of Biology, University of Copenhagen, Universitetsparken 13, DK-2100, Copenhagen Ø, Denmark.
| | - Stine Falsig Pedersen
- Section for Cell Biology and Physiology, Department of Biology, University of Copenhagen, Universitetsparken 13, DK-2100, Copenhagen Ø, Denmark.
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15
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The role of fibroblast growth factor 23 and Klotho in uremic cardiomyopathy. Curr Opin Nephrol Hypertens 2018; 25:314-24. [PMID: 27219043 DOI: 10.1097/mnh.0000000000000231] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
PURPOSE OF REVIEW In chronic kidney disease (CKD), multiple factors contribute to the development of cardiac hypertrophy by directly targeting the heart or indirectly by inducing systemic changes such as hypertension, anemia, and inflammation. Furthermore, disturbances in phosphate metabolism have been identified as nonclassical risk factors for cardiovascular mortality in these patients. With declining kidney function, the physiologic regulators of phosphate homeostasis undergo changes in their activity as well as their circulating levels, thus potentially contributing to cardiac hypertrophy once they are out of balance. Recently, two of these phosphate regulators, fibroblast growth factor 23 (FGF23) and Klotho, have been shown to affect cardiac remodeling, thereby unveiling a novel pathomechanism of cardiac hypertrophy in CKD. Here we discuss the potential direct versus indirect effects of FGF23 and the soluble form of Klotho on the heart, and their crosstalk in the regulation of cardiac hypertrophy. RECENT FINDINGS In models of CKD, FGF23 can directly target cardiac myocytes via FGF receptor 4 and induce cardiac hypertrophy in a blood pressure-independent manner. Soluble Klotho may directly target the heart via an unknown receptor thereby protecting the myocardium from pathologic stress stimuli that are associated with CKD, such as uremic toxins or FGF23. SUMMARY Elevated serum levels of FGF23 and reduced serum levels of soluble Klotho contribute to uremic cardiomyopathy in a synergistic manner.
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16
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Zeng T, Duan X, Zhu W, Liu Y, Wu W, Zeng G. SaRNA-mediated activation of TRPV5 reduces renal calcium oxalate deposition in rat via decreasing urinary calcium excretion. Urolithiasis 2017; 46:271-278. [PMID: 28776078 DOI: 10.1007/s00240-017-1004-z] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/25/2016] [Accepted: 07/23/2017] [Indexed: 01/29/2023]
Abstract
Hypercalciuria is a main risk factor for kidney stone formation. TRPV5 is the gatekeeper protein for mediating calcium transport and reabsorption in the kidney. In the present study, we tested the effect of TRPV5 activation with small activating RNA (saRNA), which could induce gene expression by targeting the promoter of the gene, on ethylene glycol (EG)-induced calcium oxalate (CaOx) crystals formation in rat kidney. Five pairs of RNA activation sequences targeting the promoter of rat TRPV5 were designed and synthesized. The synthesized saRNA with the strongest activating effect was selected, and transcellular calcium transportation was tested by Fura-2 analysis. Subsequently, Sprague-Dawley rats were equally divided into three groups and fed with water, 1% EG for 28 days after injecting the negative control saRNA, 1% EG for 28 days after injecting the selected TRPV5-saRNA, respectively. The CaOx crystal formation and the 24-h urine components were assessed. In vitro study, saRNA ds-320 could significantly activate the expression of TRPV5 and transcellular calcium transportation. In vivo study, after 28 days treatment of EG, rats pre-infected with saRNA ds-320 had lower urinary calcium excretion and renal CaOx crystals formation as compared to that pre-infected with negative control saRNA. Activation of TRVP5 with saRNA ds-320 could inhibit EG-induced calcium oxalate crystals formation via promoting urine calcium reabsorption and decreasing urine calcium excretion in rats.
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Affiliation(s)
- Tao Zeng
- Department of Urology, Minimally Invasive Surgery Center, The First Affiliated Hospital of Guangzhou Medical University, Kangda Road 1#, Haizhu District, Guangzhou, 510230, Guangdong, China.,Guangdong Key Laboratory of Urology, Minimally Invasive Surgery Center, The First Affiliated Hospital of Guangzhou Medical University, Kangda Road 1#, Haizhu District, Guangzhou, 510230, Guangdong, China
| | - Xiaolu Duan
- Department of Urology, Minimally Invasive Surgery Center, The First Affiliated Hospital of Guangzhou Medical University, Kangda Road 1#, Haizhu District, Guangzhou, 510230, Guangdong, China.,Guangdong Key Laboratory of Urology, Minimally Invasive Surgery Center, The First Affiliated Hospital of Guangzhou Medical University, Kangda Road 1#, Haizhu District, Guangzhou, 510230, Guangdong, China
| | - Wei Zhu
- Department of Urology, Minimally Invasive Surgery Center, The First Affiliated Hospital of Guangzhou Medical University, Kangda Road 1#, Haizhu District, Guangzhou, 510230, Guangdong, China.,Guangdong Key Laboratory of Urology, Minimally Invasive Surgery Center, The First Affiliated Hospital of Guangzhou Medical University, Kangda Road 1#, Haizhu District, Guangzhou, 510230, Guangdong, China
| | - Yang Liu
- Department of Urology, Minimally Invasive Surgery Center, The First Affiliated Hospital of Guangzhou Medical University, Kangda Road 1#, Haizhu District, Guangzhou, 510230, Guangdong, China.,Guangdong Key Laboratory of Urology, Minimally Invasive Surgery Center, The First Affiliated Hospital of Guangzhou Medical University, Kangda Road 1#, Haizhu District, Guangzhou, 510230, Guangdong, China
| | - Wenqi Wu
- Department of Urology, Minimally Invasive Surgery Center, The First Affiliated Hospital of Guangzhou Medical University, Kangda Road 1#, Haizhu District, Guangzhou, 510230, Guangdong, China.,Guangdong Key Laboratory of Urology, Minimally Invasive Surgery Center, The First Affiliated Hospital of Guangzhou Medical University, Kangda Road 1#, Haizhu District, Guangzhou, 510230, Guangdong, China
| | - Guohua Zeng
- Department of Urology, Minimally Invasive Surgery Center, The First Affiliated Hospital of Guangzhou Medical University, Kangda Road 1#, Haizhu District, Guangzhou, 510230, Guangdong, China. .,Guangdong Key Laboratory of Urology, Minimally Invasive Surgery Center, The First Affiliated Hospital of Guangzhou Medical University, Kangda Road 1#, Haizhu District, Guangzhou, 510230, Guangdong, China.
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17
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Radhakrishnan VM, Gilpatrick MM, Parsa NA, Kiela PR, Ghishan FK. Expression of Cav1.3 calcium channel in the human and mouse colon: posttranscriptional inhibition by IFNγ. Am J Physiol Gastrointest Liver Physiol 2017; 312:G77-G84. [PMID: 27932504 PMCID: PMC5283901 DOI: 10.1152/ajpgi.00394.2016] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/08/2016] [Revised: 12/05/2016] [Accepted: 12/06/2016] [Indexed: 01/31/2023]
Abstract
It has been hypothesized that apically expressed L-type Ca2+ channel Cav1.3 (encoded by CACNA1D gene) contributes toward an alternative TRPV6-independent route of intestinal epithelial Ca2+ absorption, especially during digestion when high luminal concentration of Ca2+ and other nutrients limit TRPV6 contribution. We and others have implicated altered expression and activity of key mediators of intestinal and renal Ca2+ (re)absorption as contributors to negative systemic Ca2+ balance and bone loss in intestinal inflammation. Here, we investigated the effects of experimental colitis and related inflammatory mediators on colonic Cav1.3 expression. We confirmed Cav1.3 expression within the segments of the mouse and human gastrointestinal tract. Consistent with available microarray data (GEO database) from inflammatory bowel disease (IBD) patients, mouse colonic expression of Cav1.3 was significantly reduced in trinitrobenzene sulfonic acid (TNBS) colitis. In vitro, IFNγ most potently reduced Cav1.3 expression. We reproduced these findings in vivo with wild-type and Stat1-/- mice injected with IFNγ. The observed effect in Stat1-/- suggested a noncanonical transcriptional repression or a posttranscriptional mechanism. In support of the latter, we observed no effect on the cloned Cav1.3 gene promoter activity and accelerated Cav1.3 mRNA decay rate in IFNγ-treated HCT116 cells. While the relative contribution of Cav1.3 to intestinal Ca2+ absorption and its value as a therapeutic target remain to be established, we postulate that Cav1.3 downregulation in IBD may contribute to the negative systemic Ca2+ balance, to increased bone resorption, and to reduced bone mineral density in IBD patients.
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Affiliation(s)
| | | | - Nour Alhoda Parsa
- 1Department of Pediatrics, The University of Arizona, Tucson, Arizona; and
| | - Pawel R. Kiela
- 1Department of Pediatrics, The University of Arizona, Tucson, Arizona; and ,2Department of Immunobiology, The University of Arizona, Tucson, Arizona
| | - Fayez K. Ghishan
- 1Department of Pediatrics, The University of Arizona, Tucson, Arizona; and
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18
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Sopjani M, Dërmaku-Sopjani M. Klotho-Dependent Cellular Transport Regulation. VITAMINS AND HORMONES 2016; 101:59-84. [PMID: 27125738 DOI: 10.1016/bs.vh.2016.02.003] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Klotho is a transmembrane protein that in humans is encoded by the hKL gene. This protein is known to have aging suppressor effects and is predominantly expressed in the distal convoluted tubule of the kidney, parathyroid glands, and choroid plexus of the brain. The Klotho protein exists in both full-length membrane form and a soluble secreted form, which exerts numerous distinct functions. The extracellular domain of Klotho can be enzymatically cleaved off and released into the systemic circulation where it functions as β-glucuronidase and a hormone. Soluble Klotho is a multifunction protein present in the biological fluids including blood, urine, and cerebrospinal fluid of mammals. Klotho deficiency leads to multiple organ failure accompanied by early appearance of multiple age-related disorders and early death, whereas overexpression of Klotho results in the opposite effects. Klotho, an enzyme and hormone, has been reported to participate in the regulation of cellular transport processes across the plasma membrane either indirectly through inhibiting calcitriol (1,25(OH)2D3) formation or other mechanism, or by directly affecting transporter proteins, including ion channels, cellular carriers, and Na(+)/K(+)-ATPase. Accordingly, Klotho protein serves as a powerful regulator of cellular transport across the plasma membrane. Importantly, Klotho-dependent cellular transport regulation implies stimulatory or inhibitory effects. Klotho has been shown to play a key role in the regulation of multiple calcium and potassium ion channels, and various cellular carriers including the Na(+)-coupled cotransporters such as NaPi-IIa, NaPi-IIb, EAAT3, and EAAT4, CreaT1 as well as Na(+)/K(+)-ATPase. These regulations are parts of the antiaging function of Klotho, which will be discussing throughout this chapter. Clearly, further experimental efforts are required to investigate the effect of Klotho on other transport proteins and underlying molecular mechanisms by which Klotho exerts its effect.
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Affiliation(s)
- M Sopjani
- University of Prishtina, Prishtinë, Republic of Kosova.
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19
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Ohya S, Kito H, Hatano N, Muraki K. Recent advances in therapeutic strategies that focus on the regulation of ion channel expression. Pharmacol Ther 2016; 160:11-43. [PMID: 26896566 DOI: 10.1016/j.pharmthera.2016.02.001] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
A number of different ion channel types are involved in cell signaling networks, and homeostatic regulatory mechanisms contribute to the control of ion channel expression. Profiling of global gene expression using microarray technology has recently provided novel insights into the molecular mechanisms underlying the homeostatic and pathological control of ion channel expression. It has demonstrated that the dysregulation of ion channel expression is associated with the pathogenesis of neural, cardiovascular, and immune diseases as well as cancers. In addition to the transcriptional, translational, and post-translational regulation of ion channels, potentially important evidence on the mechanisms controlling ion channel expression has recently been accumulated. The regulation of alternative pre-mRNA splicing is therefore a novel therapeutic strategy for the treatment of dominant-negative splicing disorders. Epigenetic modification plays a key role in various pathological conditions through the regulation of pluripotency genes. Inhibitors of pre-mRNA splicing and histone deacetyalase/methyltransferase have potential as potent therapeutic drugs for cancers and autoimmune and inflammatory diseases. Moreover, membrane-anchoring proteins, lysosomal and proteasomal degradation-related molecules, auxiliary subunits, and pharmacological agents alter the protein folding, membrane trafficking, and post-translational modifications of ion channels, and are linked to expression-defect channelopathies. In this review, we focused on recent insights into the transcriptional, spliceosomal, epigenetic, and proteasomal regulation of ion channel expression: Ca(2+) channels (TRPC/TRPV/TRPM/TRPA/Orai), K(+) channels (voltage-gated, KV/Ca(2+)-activated, KCa/two-pore domain, K2P/inward-rectifier, Kir), and Ca(2+)-activated Cl(-) channels (TMEM16A/TMEM16B). Furthermore, this review highlights expression of these ion channels in expression-defect channelopathies.
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Affiliation(s)
- Susumu Ohya
- Department of Pharmacology, Division of Pathological Sciences, Kyoto Pharmaceutical University, Kyoto 607-8414, Japan.
| | - Hiroaki Kito
- Department of Pharmacology, Division of Pathological Sciences, Kyoto Pharmaceutical University, Kyoto 607-8414, Japan
| | - Noriyuki Hatano
- Laboratory of Cellular Pharmacology, School of Pharmacy, Aichi-Gakuin University, Nagoya 464-8650, Japan
| | - Katsuhiko Muraki
- Laboratory of Cellular Pharmacology, School of Pharmacy, Aichi-Gakuin University, Nagoya 464-8650, Japan.
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20
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RamaKrishnan AM, Sankaranarayanan K. Understanding autoimmunity: The ion channel perspective. Autoimmun Rev 2016; 15:585-620. [PMID: 26854401 DOI: 10.1016/j.autrev.2016.02.004] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2016] [Accepted: 01/29/2016] [Indexed: 12/11/2022]
Abstract
Ion channels are integral membrane proteins that orchestrate the passage of ions across the cell membrane and thus regulate various key physiological processes of the living system. The stringently regulated expression and function of these channels hold a pivotal role in the development and execution of various cellular functions. Malfunction of these channels results in debilitating diseases collectively termed channelopathies. In this review, we highlight the role of these proteins in the immune system with special emphasis on the development of autoimmunity. The role of ion channels in various autoimmune diseases is also listed out. This comprehensive review summarizes the ion channels that could be used as molecular targets in the development of new therapeutics against autoimmune disorders.
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Affiliation(s)
| | - Kavitha Sankaranarayanan
- AU-KBC Research Centre, Madras Institute of Technology, Anna University, Chrompet, Chennai 600 044, India.
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21
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Brückner M, Lenz P, Mücke MM, Gohar F, Willeke P, Domagk D, Bettenworth D. Diagnostic imaging advances in murine models of colitis. World J Gastroenterol 2016; 22:996-1007. [PMID: 26811642 PMCID: PMC4716050 DOI: 10.3748/wjg.v22.i3.996] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/29/2015] [Revised: 09/09/2015] [Accepted: 11/13/2015] [Indexed: 02/06/2023] Open
Abstract
Inflammatory bowel diseases (IBD) such as Crohn’s disease and ulcerative colitis are chronic-remittent inflammatory disorders of the gastrointestinal tract still evoking challenging clinical diagnostic and therapeutic situations. Murine models of experimental colitis are a vital component of research into human IBD concerning questions of its complex pathogenesis or the evaluation of potential new drugs. To monitor the course of colitis, to the present day, classical parameters like histological tissue alterations or analysis of mucosal cytokine/chemokine expression often require euthanasia of animals. Recent advances mean revolutionary non-invasive imaging techniques for in vivo murine colitis diagnostics are increasingly available. These novel and emerging imaging techniques not only allow direct visualization of intestinal inflammation, but also enable molecular imaging and targeting of specific alterations of the inflamed murine mucosa. For the first time, in vivo imaging techniques allow for longitudinal examinations and evaluation of intra-individual therapeutic response. This review discusses the latest developments in the different fields of ultrasound, molecularly targeted contrast agent ultrasound, fluorescence endoscopy, confocal laser endomicroscopy as well as tomographic imaging with magnetic resonance imaging, computed tomography and fluorescence-mediated tomography, discussing their individual limitations and potential future diagnostic applications in the management of human patients with IBD.
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A Single Nucleotide Polymorphism (rs4236480) in TRPV5 Calcium Channel Gene Is Associated with Stone Multiplicity in Calcium Nephrolithiasis Patients. Mediators Inflamm 2015; 2015:375427. [PMID: 26089600 PMCID: PMC4452106 DOI: 10.1155/2015/375427] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2014] [Revised: 03/31/2015] [Accepted: 04/17/2015] [Indexed: 12/11/2022] Open
Abstract
Nephrolithiasis is characterized by calcification of stones in the kidneys from an unknown cause. Animal models demonstrated the functional roles of the transient receptor potential vanilloid member 5 (TRPV5) gene in calcium renal reabsorption and hypercalciuria. Therefore, TRPV5 was suggested to be involved in calcium homeostasis. However, whether genetic polymorphisms of TRPV5 are associated with kidney stone multiplicity or recurrence is unclear. In this study, 365 Taiwanese kidney-stone patients were recruited. Both biochemical data and DNA samples were collected. Genotyping was performed by a TaqMan allelic discrimination assay. We found that a TRPV5 polymorphism (rs4236480) was observed to be associated with stone multiplicity of calcium nephrolithiasis, as the risk of stone multiplicity was higher in patients with the TT+CT genotype than in patients with the CC genotype (p = 0.0271). In summary, despite the complexity of nephrolithiasis and the potential association of numerous calcium homeostatic absorption/reabsorption factors, TRPV5 plays an important role in the pathogenesis of calcium nephrolithiasis.
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Kim JH, Hwang KH, Park KS, Kong ID, Cha SK. Biological Role of Anti-aging Protein Klotho. J Lifestyle Med 2015; 5:1-6. [PMID: 26528423 PMCID: PMC4608225 DOI: 10.15280/jlm.2015.5.1.1] [Citation(s) in RCA: 125] [Impact Index Per Article: 13.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2014] [Accepted: 02/16/2015] [Indexed: 12/15/2022] Open
Abstract
Klotho-deficient mice have accelerated aging phenotypes, whereas overexpression of Klotho in mice extends lifespan. Klotho is an anti-aging single-pass membrane protein predominantly produced in the kidney, with shedding of the amino-terminal extracellular domain into the systemic circulation. Circulating levels of soluble Klotho decrease with age, and the klotho gene is associated with increased risk of age-related diseases. The three forms of Klotho protein have distinct functions. Membrane Klotho forms a complex with fibroblast growth factor (FGF) receptors, functions as an obligatory co-receptor for FGF23, which is involved in aging and the development of chronic diseases via regulation of Pi and vitamin D metabolism. Secreted Klotho functions as a humoral factor with pleiotropic activities including regulation of oxidative stress, growth factor signaling, and ion homeostasis. Secreted Klotho is also involved in organ protection. The intracellular form of Klotho suppresses inflammation-mediated cellular senescence and mineral metabolism. Herein we provide a brief overview of the structure and function and recent research about Klotho.
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Affiliation(s)
- Ji-Hee Kim
- Departments of Physiology and Global Medical Science, Yonsei University Wonju College of Medicine, Wonju, Korea
| | - Kyu-Hee Hwang
- Departments of Physiology and Global Medical Science, Yonsei University Wonju College of Medicine, Wonju, Korea
| | - Kyu-Sang Park
- Departments of Physiology and Global Medical Science, Yonsei University Wonju College of Medicine, Wonju, Korea ; Institute of Lifestyle Medicine, Yonsei University Wonju College of Medicine, Wonju, Korea
| | - In Deok Kong
- Departments of Physiology and Global Medical Science, Yonsei University Wonju College of Medicine, Wonju, Korea ; Institute of Lifestyle Medicine, Yonsei University Wonju College of Medicine, Wonju, Korea
| | - Seung-Kuy Cha
- Departments of Physiology and Global Medical Science, Yonsei University Wonju College of Medicine, Wonju, Korea ; Institute of Lifestyle Medicine, Yonsei University Wonju College of Medicine, Wonju, Korea ; Nuclear Receptor Research Consortium, Yonsei University Wonju College of Medicine, Wonju, Korea
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Parsons K, Nakatani Y, Nguyen MD. p600/UBR4 in the central nervous system. Cell Mol Life Sci 2015; 72:1149-60. [PMID: 25424645 PMCID: PMC11113099 DOI: 10.1007/s00018-014-1788-8] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2014] [Revised: 11/06/2014] [Accepted: 11/17/2014] [Indexed: 10/24/2022]
Abstract
A decade ago, the large 600 kDa mammalian protein p600 (also known as UBR4) was discovered as a multifunctional protein with roles in anoikis, viral transformation and protein degradation. Recently, p600 has emerged as a critical protein in the mammalian brain with roles in neurogenesis, neuronal migration, neuronal signaling and survival. How p600 integrates these apparently unrelated functions to maintain tissue homeostasis and murine survival remains unclear. The common molecular basis underlying many of the actions of p600 suggests, however, certain conservation and transposition of these functions across systems. In this review, we summarize the central nervous system functions of p600 and propose new perspectives on its biological complexity in neuronal physiology and neurological diseases.
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Affiliation(s)
- Kari Parsons
- Department of Clinical Neurosciences, University of Calgary, Hotchkiss Brain Institute, 3330 Hospital Drive NW, Calgary, T2N 4N1, Canada,
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Radhakrishnan VM, Kojs P, Ramalingam R, Midura-Kiela MT, Angeli P, Kiela PR, Ghishan FK. Experimental colitis is associated with transcriptional inhibition of Na+/Ca2+ exchanger isoform 1 (NCX1) expression by interferon γ in the renal distal convoluted tubules. J Biol Chem 2015; 290:8964-74. [PMID: 25648899 DOI: 10.1074/jbc.m114.616516] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2014] [Indexed: 01/20/2023] Open
Abstract
NCX1 is a Na(+)/Ca(2+) exchanger, which is believed to provide a key route for basolateral Ca(2+) efflux in the renal epithelia, thus contributing to renal Ca(2+) reabsorption. Altered mineral homeostasis, including intestinal and renal Ca(2+) transport may represent a significant component of the pathophysiology of the bone mineral density loss associated with Inflammatory Bowel Diseases (IBD). The objective of our research was to investigate the effects of TNBS and DSS colitis and related inflammatory mediators on renal Ncx1 expression. Colitis was associated with decreased renal Ncx1 expression, as examined by real-time RT-PCR, Western blotting, and immunofluorescence. In mIMCD3 cells, IFNγ significantly reduced Ncx1 mRNA and protein expression. Similar effects were observed in cells transiently transfected with a reporter construct bearing the promoter region of the kidney-specific Ncx1 gene. This inhibitory effect of IFNγ is mediated by STAT1 recruitment to the proximal promoter region of Ncx1. Further in vivo study with Stat1(-/-) mice confirmed that STAT1 is indeed required for the IFNγ mediated Ncx1 gene regulation. These results strongly support the hypothesis that impaired renal Ca(2+) handling occurs in experimental colitis. Negative regulation of NCX1- mediated renal Ca(2+) absorption by IFNγ may significantly contribute to the altered Ca(2+) homeostasis in IBD patients and to IBD-associated loss of bone mineral density.
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Affiliation(s)
| | - Pawel Kojs
- From the Departments of Pediatrics, Steele Children's Research Center and
| | | | | | - Peter Angeli
- Zanvyl Krieger School of Arts and Sciences Johns Hopkins University, Baltimore, Maryland 21218
| | - Pawel R Kiela
- From the Departments of Pediatrics, Steele Children's Research Center and Immunobiology, University of Arizona Health Sciences Center, Tucson, Arizona 85724, and
| | - Fayez K Ghishan
- From the Departments of Pediatrics, Steele Children's Research Center and
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Abstract
The epithelium of the gastrointestinal tract is one of the most versatile tissues in the organism, responsible for providing a tight barrier between dietary and bacterial antigens and the mucosal and systemic immune system while maintaining efficient digestive and absorptive processes to ensure adequate nutrient and energy supply. Inflammatory bowel diseases (Crohn's disease and ulcerative colitis) are associated with a breakdown of both functions, which in some cases are clearly interrelated. In this updated literature review, we focus on the effects of intestinal inflammation and the associated immune mediators on selected aspects of the transepithelial transport of macronutrients and micronutrients. The mechanisms responsible for nutritional deficiencies are not always clear and could be related to decreased intake, malabsorption, and excess losses. We summarize the known causes of nutrient deficiencies and the mechanism of inflammatory bowel disease-associated diarrhea. We also overview the consequences of impaired epithelial transport, which infrequently transcend its primary purpose to affect the gut microbial ecology and epithelial integrity. Although some of those regulatory mechanisms are relatively well established, more work needs to be done to determine how inflammatory cytokines can alter the transport process of nutrients across the gastrointestinal and renal epithelia.
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Abstract
TRPV5 is one of the two channels in the TRPV family that exhibit high selectivity to Ca(2+) ions. TRPV5 mediates Ca(2+) influx into cells as the first step to transport Ca(2+) across epithelia. The specialized distribution in the distal tubule of the kidney positions TRPV5 as a key player in Ca(2+) reabsorption. The responsiveness in expression and/or activity of TRPV5 to hormones such as 1,25-dihydroxyvitamin D3, parathyroid hormone, estrogen, and testosterone makes TRPV5 suitable for its role in the fine-tuning of Ca(2+) reabsorption. This role is further optimized by the modulation of TRPV5 trafficking and activity via its binding partners; co-expressed proteins; tubular factors such as calbindin-D28k, calmodulin, klotho, uromodulin, and plasmin; extracellular and intracellular factors such as proton, Mg(2+), Ca(2+), and phosphatidylinositol-4,5-bisphosphate; and fluid flow. These regulations allow TRPV5 to adjust its overall activity in response to the body's demand for Ca(2+) and to prevent kidney stone formation. A point mutation in mouse Trpv5 gene leads to hypercalciuria similar to Trpv5 knockout mice, suggesting a possible role of TRPV5 in hypercalciuric disorders in humans. In addition, the single nucleotide polymorphisms in Trpv5 gene prevalently present in African descents may contribute to the efficient renal Ca(2+) reabsorption among African descendants. TRPV5 represents a potential therapeutic target for disorders with altered Ca(2+) homeostasis.
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Affiliation(s)
- Tao Na
- Cell Collection and Research Center, Institute for Biological Product Control, National Institutes for Food and Drug Control, Beijing, China
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