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Xiao J, Lv J, Wang S, Zhou Y, Chen L, Lu J, Zhang X, Wang X, Gu Y, Lu Q. Association of serum 25-hydroxyvitamin D with metabolic syndrome and type 2 diabetes: a one sample Mendelian randomization study. BMC Geriatr 2021; 21:391. [PMID: 34187381 PMCID: PMC8244233 DOI: 10.1186/s12877-021-02307-6] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2021] [Accepted: 05/25/2021] [Indexed: 01/08/2023] Open
Abstract
Background Vitamin D deficiency has been associated with type 2 diabetes (T2D) and metabolic syndrome (MS) and its components. However, it is unclear whether a low concentration of vitamin D is the cause or consequence of these health conditions. Thus, this study aimed to evaluate the association of vitamin D concentrations and its genetic risk scores (GRSs) with MS and its component diseases, such as T2D, in middle-aged and elderly participants from rural eastern China. Methods A subset of 2393 middle-aged and elderly individuals were selected from 70,458 participants of the Nantong Chronic Diseases Study of 2017–2018 in China. We used two 25-hydroxyvitamin D (25[OH]D) synthesis single-nucleotide polymorphisms (SNPs) (DHCR7-rs12785878 and CYP2R1-rs10741657) and two 25(OH) D metabolism SNPs (GC-rs2282679 and CYP24A1-rs6013897) for creating GRSs, which were used as instrumental variables to assess the effect of genetically lowered 25(OH) D concentrations on MS and T2D based on the Wald ratio. F statistics were used to validate that the four SNPs genetically determined 25(OH) D concentrations. Results Compared to vitamin D sufficient individuals, individuals with vitamin D insufficiency had an odds ratio (OR [95% confidence interval {CI}]) of MS of 1.30 (1.06–1.61) and of T2D of 1.32 (1.08–1.64), individuals with vitamin D deficiency had an ORs (95% CI) of MS of 1.50 (1.24–1.79) and of T2D of 1.47 (1.12–1.80), and those with vitamin D severe deficiency had an ORs (95% CI) of MS of 1.52 (1.29–1.85) and of T2D of 1.54 (1.27–1.85). Mendelian randomization analysis showed a 25-nmol/L decrease in genetically instrumented serum 25(OH) D concentrations using the two synthesis SNPs (DHCR7 and CYP2R1 genes) associated with the risk of T2D and abnormal diastolic blood pressure (DBP) with ORs of 1.10 (95%CI: 1.02–1.45) for T2D and 1.14 (95%CI: 1.03–1.43) for DBP. Conclusions This one sample Mendelian randomization analysis shows genetic evidence for a causal role of lower 25(OH) D concentrations in promoting of T2D and abnormal DBP in middle-aged and elderly participants from rural China. Supplementary Information The online version contains supplementary material available at 10.1186/s12877-021-02307-6.
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Affiliation(s)
- Jing Xiao
- Department of Epidemiology and Medical Statistics, School of Public Health, Nantong University, No.9 Seyuan Road, Chongchuan District, Nantong, Jiangsu, P.R. China, 226019
| | - Jingyi Lv
- Department of Epidemiology and Medical Statistics, School of Public Health, Nantong University, No.9 Seyuan Road, Chongchuan District, Nantong, Jiangsu, P.R. China, 226019
| | - Shiyu Wang
- Department of Epidemiology and Medical Statistics, School of Public Health, Nantong University, No.9 Seyuan Road, Chongchuan District, Nantong, Jiangsu, P.R. China, 226019
| | - Yang Zhou
- Department of Epidemiology and Medical Statistics, School of Public Health, Nantong University, No.9 Seyuan Road, Chongchuan District, Nantong, Jiangsu, P.R. China, 226019
| | - Lunwen Chen
- Department of Epidemiology and Medical Statistics, School of Public Health, Nantong University, No.9 Seyuan Road, Chongchuan District, Nantong, Jiangsu, P.R. China, 226019
| | - Juying Lu
- Department of Endocrinology and Metabolism, Affiliated Hospital of Nantong University, No.20 Xisi Road, Chongchuan District, Nantong, Jiangsu, P.R. China, 226001
| | - Xiaoyi Zhang
- Department of Endocrinology and Metabolism, Affiliated Hospital of Nantong University, No.20 Xisi Road, Chongchuan District, Nantong, Jiangsu, P.R. China, 226001
| | - Xiaojian Wang
- Department of Chronic Disease and Prevention, Center for Disease Control and Prevention of Haian, Nantong, Jiangsu, P.R. China, 226600
| | - Yunjuan Gu
- Department of Endocrinology and Metabolism, Affiliated Hospital of Nantong University, No.20 Xisi Road, Chongchuan District, Nantong, Jiangsu, P.R. China, 226001.
| | - Qingyun Lu
- Department of Epidemiology and Medical Statistics, School of Public Health, Nantong University, No.9 Seyuan Road, Chongchuan District, Nantong, Jiangsu, P.R. China, 226019.
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Bikle DD. The Free Hormone Hypothesis: When, Why, and How to Measure the Free Hormone Levels to Assess Vitamin D, Thyroid, Sex Hormone, and Cortisol Status. JBMR Plus 2020; 5:e10418. [PMID: 33553985 PMCID: PMC7839820 DOI: 10.1002/jbm4.10418] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/01/2020] [Revised: 08/29/2020] [Accepted: 09/22/2020] [Indexed: 12/13/2022] Open
Abstract
The free hormone hypothesis postulates that only the nonbound fraction (the free fraction) of hormones that otherwise circulate in blood bound to their carrier proteins is able to enter cells and exert biologic effects. In this review, I will examine four hormone groups-vitamin D metabolites (especially 25OHD), thyroid hormones (especially thyroxine [T4]), sex steroids (especially testosterone), and glucocorticoids (especially cortisol)-that are bound to various degrees to their respective binding proteins-vitamin D-binding protein (DBP), thyroid-binding globulin (TBG), sex hormone-binding globulin (SHBG), and cortisol-binding globulin (CBG)-for which a strong case can be made that measurement of the free hormone level provides a better assessment of hormonal status than the measurement of total hormonal levels under conditions in which the binding proteins are affected in levels or affinities for the hormones to which they bind. I will discuss the rationale for this argument based on the free hormone hypothesis, discuss potential exceptions to the free hormone hypothesis, and review functions of the binding proteins that may be independent of their transport role. I will then review the complications involved with measuring the free hormone levels and the efforts to calculate those levels based on estimates of binding constants and levels of both total hormone and total binding protein. In this review, the major focus will be on DBP and free 25OHD, but the parallels and differences with the other binding proteins and hormones will be highlighted. Vitamin D and its metabolites, thyroid hormones, sex steroids, and glucocorticoids are transported in blood bound to serum proteins. The tightness of binding varies depending on the hormone and the binding protein such that the percent free varies from 0.03% for T4 and 25OHD to 4% for cortisol with testosterone at 2%. Although the major function of the primary carrier proteins (DBP, TBG, SHBG, and CBG) may be to transport their respective lipophilic hormones within the aqueous media that is plasma, these proteins may have other functions independent of their transport function. For most tissues, these hormones enter the cell as the free hormone presumably by diffusion (the free hormone hypothesis), although a few tissues such as the kidney and reproductive tissues express megalin/cubilin enabling by endocytosis protein-bound hormone to enter the cell. Measuring the free levels of these protein-bound hormones is likely to provide a better measure of the true hormone status than measuring the total levels in situations where the levels and/or affinities of the binding proteins are altered. Methods to measure free hormone levels are problematic as the free levels can be quite low, the methods require separation of bound and free that could disturb the steady state, and the means of separating bound and free are prone to error. Calculation of free levels using existing data for association constants between the hormone and its binding protein are likewise prone to error because of assumptions of linear binding models and invariant association constants, both of which are invalid. © 2020 The Author. JBMR Plus published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research.
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Affiliation(s)
- Daniel D Bikle
- Department of Medicine University of California San Francisco USA.,Department of Medicine San Francisco VA Medical Center San Francisco CA USA
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Bikle DD, Schwartz J. Vitamin D Binding Protein, Total and Free Vitamin D Levels in Different Physiological and Pathophysiological Conditions. Front Endocrinol (Lausanne) 2019; 10:317. [PMID: 31191450 PMCID: PMC6546814 DOI: 10.3389/fendo.2019.00317] [Citation(s) in RCA: 213] [Impact Index Per Article: 42.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/25/2019] [Accepted: 05/01/2019] [Indexed: 12/19/2022] Open
Abstract
This review focuses on the biologic importance of the vitamin D binding protein (DBP) with emphasis on its regulation of total and free vitamin D metabolite levels in various clinical conditions. Nearly all DBP is produced in the liver, where its regulation is influenced by estrogen, glucocorticoids and inflammatory cytokines but not by vitamin D itself. DBP is the most polymorphic protein known, and different DBP alleles can have substantial impact on its biologic functions. The three most common alleles-Gc1f, Gc1s, Gc2-differ in their affinity with the vitamin D metabolites and have been variably associated with a number of clinical conditions. Although DBP has a number of biologic functions independent of vitamin D, its major biologic function is that of regulating circulating free and total levels of vitamin D metabolites. 25 hydroxyvitamin D (25(OH)D) is the best studied form of vitamin D as it provides the best measure of vitamin D status. In a normal non-pregnant individual, approximately 0.03% of 25(OH)D is free; 85% is bound to DBP, 15% is bound to albumin. The free hormone hypothesis postulates that only free 25(OH)D can enter cells. This hypothesis is supported by the observation that mice lacking DBP, and therefore with essentially undetectable 25(OH)D levels, do not show signs of vitamin D deficiency unless put on a vitamin D deficient diet. Similar observations have recently been described in a family with a DBP mutation. This hypothesis also applies to other protein bound lipophilic hormones including glucocorticoids, sex steroids, and thyroid hormone. However, tissues expressing the megalin/cubilin complex, such as the kidney, have the capability of taking up 25(OH)D still bound to DBP, but most tissues rely on the free level. Attempts to calculate the free level using affinity constants generated in a normal individual along with measurement of DBP and total 25(OH)D have not accurately reflected directly measured free levels in a number of clinical conditions. In this review, we examine the impact of different clinical conditions as well as different DBP alleles on the relationship between total and free 25(OH)D, using only data in which the free 25(OH)D level was directly measured. The major conclusion is that a number of clinical conditions alter this relationship, raising the question whether measuring just total 25(OH)D might be misleading regarding the assessment of vitamin D status, and such assessment might be improved by measuring free 25(OH)D instead of or in addition to total 25(OH)D.
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Affiliation(s)
- Daniel David Bikle
- Department of Medicine, University of California, San Francisco, San Francisco, CA, United States
- Endocrine Research Unit, San Francisco Veterans Affairs Medical Center, San Francisco, CA, United States
- *Correspondence: Daniel David Bikle
| | - Janice Schwartz
- Department of Medicine, University of California, San Francisco, San Francisco, CA, United States
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Miller S, Coveney C, Johnson J, Farmaki AE, Gupta N, Tobin MD, Wain LV, McCormack FX, Boocock DJ, Johnson SR. The vitamin D binding protein axis modifies disease severity in lymphangioleiomyomatosis. Eur Respir J 2018; 52:1800951. [PMID: 30093573 PMCID: PMC6214577 DOI: 10.1183/13993003.00951-2018] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2018] [Accepted: 07/29/2018] [Indexed: 12/31/2022]
Abstract
Lymphangioleiomyomatosis (LAM) is a rare disease of women. Decline in lung function is variable, making appropriate targeting of therapy difficult. We used unbiased serum proteomics to identify markers associated with outcome in LAM.101 women with LAM and 22 healthy controls were recruited from the National Centre for LAM in the UK. 152 DNA and serum samples with linked lung function and outcome data were obtained from patients in the National Heart, Lung and Blood Institute LAM Registry in the USA. Proteomic analysis was performed on a discovery cohort of 50 LAM and 20 control serum samples using a SCIEX SWATH mass spectrometric workflow. Protein levels were quantitated by ELISA and single nucleotide polymorphisms in GC (group-specific component) encoding vitamin D binding protein (VTDB) were genotyped.Proteomic analysis showed VTDB was 2.6-fold lower in LAM than controls. Serum VTDB was lower in progressive compared with stable LAM (p=0.001) and correlated with diffusing capacity of the lung for carbon monoxide (p=0.01). Median time to death or lung transplant was reduced by 46 months in those with CC genotypes at rs4588 and 38 months in those with non-A-containing haplotypes at rs7041/4588 (p=0.014 and 0.008, respectively).The VTDB axis is associated with disease severity and outcome, and GC genotype could help predict transplant-free survival in LAM.
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Affiliation(s)
- Suzanne Miller
- Division of Respiratory Medicine, University of Nottingham and National Institute for Health Research, Respiratory Biomedical Research Centre, Nottingham, UK
| | - Clare Coveney
- John van Geest Cancer Research Centre, Nottingham Trent University, Nottingham, UK
| | - Janice Johnson
- Division of Respiratory Medicine, University of Nottingham and National Institute for Health Research, Respiratory Biomedical Research Centre, Nottingham, UK
| | - Aliki-Eleni Farmaki
- Dept of Health Sciences, College of Life Sciences, University of Leicester, Leicester, UK
| | - Nishant Gupta
- Division of Pulmonary, Critical Care and Sleep Medicine, University of Cincinnati, Cincinnati, OH, USA
| | - Martin D Tobin
- Dept of Health Sciences, College of Life Sciences, University of Leicester, Leicester, UK
- National Institute for Health Research Leicester Respiratory Biomedical Research Centre, Glenfield Hospital, Leicester, UK
| | - Louise V Wain
- Dept of Health Sciences, College of Life Sciences, University of Leicester, Leicester, UK
- National Institute for Health Research Leicester Respiratory Biomedical Research Centre, Glenfield Hospital, Leicester, UK
| | - Francis X McCormack
- Division of Pulmonary, Critical Care and Sleep Medicine, University of Cincinnati, Cincinnati, OH, USA
| | - David J Boocock
- John van Geest Cancer Research Centre, Nottingham Trent University, Nottingham, UK
| | - Simon R Johnson
- Division of Respiratory Medicine, University of Nottingham and National Institute for Health Research, Respiratory Biomedical Research Centre, Nottingham, UK
- National Centre for LAM, Queen's Medical Centre, Nottingham, UK
- Nottingham Molecular Pathology Node, Nottingham, UK
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5
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Liu HJ, Henske EP. Vitamin D binding protein: a new biomarker of disease severity in lymphangioleiomyomatosis. Eur Respir J 2018; 52:52/5/1801886. [PMID: 30385604 DOI: 10.1183/13993003.01886-2018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2018] [Accepted: 10/21/2018] [Indexed: 11/05/2022]
Affiliation(s)
- Heng-Jia Liu
- Division of Pulmonary and Critical Care Medicine, Dept of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
| | - Elizabeth P Henske
- Division of Pulmonary and Critical Care Medicine, Dept of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
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Lund-Nielsen J, Vedel-Krogh S, Kobylecki CJ, Brynskov J, Afzal S, Nordestgaard BG. Vitamin D and Inflammatory Bowel Disease: Mendelian Randomization Analyses in the Copenhagen Studies and UK Biobank. J Clin Endocrinol Metab 2018; 103:3267-3277. [PMID: 29947775 DOI: 10.1210/jc.2018-00250] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/30/2018] [Accepted: 06/21/2018] [Indexed: 12/14/2022]
Abstract
CONTEXT Vitamin D may be a modifiable risk factor for inflammatory bowel disease (IBD). OBJECTIVES We tested the hypothesis that plasma 25-hydroxyvitamin D levels are causally associated with risk of Crohn disease (CD) and ulcerative colitis (UC). DESIGN, SETTING, PATIENTS, AND INTERVENTIONS We used a Mendelian randomization design to study 120,013 individuals from the Copenhagen City Heart Study, the Copenhagen General Population Study, and a Copenhagen-based cohort of patients with IBD. Of these, 35,558 individuals had plasma 25-hydroxyvitamin D measurements available, and 115,110 were genotyped for rs7944926 and rs11234027 in DHCR7 and rs10741657 and rs12794714 in CYP2R1, all variants associated with plasma 25-hydroxyvitamin D levels. We identified 653 cases of CD and 1265 cases of UC, of which 58 and 113, respectively, had 25-hydroxyvitamin D measurements available. We also included genetic data from 408,455 individuals from the UK Biobank, including 1707 CD cases and 3147 UC cases. MAIN OUTCOME MEASURE Hazard ratios for higher plasma 25-hydroxyvitamin D levels. RESULTS The multivariable-adjusted hazard ratios for 10 nmol/L higher 25-hydroxyvitamin D level were 1.04 (95% CI: 0.93 to 1.16) for CD and 1.13 (95% CI: 1.06 to 1.21) for UC. A combined 25-hydroxyvitamin D allele score was associated with a 1.4-nmol/L increase in plasma 25-hydroxyvitamin D level and hazard ratios of 0.98 (95% CI: 0.94 to 1.03) for CD and 1.01 (95% CI: 0.97 to 1.05) for UC. Combining genetic data from the Copenhagen studies and the UK Biobank, genetically determined vitamin D did not appear to influence the risk of CD or UC. CONCLUSIONS Our results do not support a major role for vitamin D deficiency in the development of IBD.
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Affiliation(s)
- Josephine Lund-Nielsen
- Department of Clinical Biochemistry, Herlev and Gentofte Hospital, Copenhagen University Hospital, Copenhagen, Herlev, Denmark
- The Copenhagen General Population Study, Herlev and Gentofte Hospital, Copenhagen University Hospital, Copenhagen, Herlev, Denmark
- Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Signe Vedel-Krogh
- Department of Clinical Biochemistry, Herlev and Gentofte Hospital, Copenhagen University Hospital, Copenhagen, Herlev, Denmark
- The Copenhagen General Population Study, Herlev and Gentofte Hospital, Copenhagen University Hospital, Copenhagen, Herlev, Denmark
| | - Camilla Jannie Kobylecki
- Department of Clinical Biochemistry, Herlev and Gentofte Hospital, Copenhagen University Hospital, Copenhagen, Herlev, Denmark
- The Copenhagen General Population Study, Herlev and Gentofte Hospital, Copenhagen University Hospital, Copenhagen, Herlev, Denmark
| | - Jørn Brynskov
- Department of Gastroenterology, Herlev and Gentofte Hospital, Copenhagen University Hospital, Copenhagen, Herlev, Denmark
| | - Shoaib Afzal
- Department of Clinical Biochemistry, Herlev and Gentofte Hospital, Copenhagen University Hospital, Copenhagen, Herlev, Denmark
- The Copenhagen General Population Study, Herlev and Gentofte Hospital, Copenhagen University Hospital, Copenhagen, Herlev, Denmark
| | - Børge G Nordestgaard
- Department of Clinical Biochemistry, Herlev and Gentofte Hospital, Copenhagen University Hospital, Copenhagen, Herlev, Denmark
- The Copenhagen General Population Study, Herlev and Gentofte Hospital, Copenhagen University Hospital, Copenhagen, Herlev, Denmark
- Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
- The Copenhagen City Heart Study, Frederiksberg Hospital, Copenhagen University Hospital, Copenhagen, Denmark
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Lu L, Bennett DA, Millwood IY, Parish S, McCarthy MI, Mahajan A, Lin X, Bragg F, Guo Y, Holmes MV, Afzal S, Nordestgaard BG, Bian Z, Hill M, Walters RG, Li L, Chen Z, Clarke R. Association of vitamin D with risk of type 2 diabetes: A Mendelian randomisation study in European and Chinese adults. PLoS Med 2018; 15:e1002566. [PMID: 29718904 PMCID: PMC5931494 DOI: 10.1371/journal.pmed.1002566] [Citation(s) in RCA: 68] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/09/2017] [Accepted: 04/06/2018] [Indexed: 12/19/2022] Open
Abstract
BACKGROUND Observational studies have reported that higher plasma 25-hydroxyvitamin D (25[OH]D) concentrations are associated with lower risks of diabetes, but it is unclear if these associations are causal. The aim of this study was to test the relevance of 25(OH)D for type 2 diabetes using genetically instrumented differences in plasma 25(OH)D concentrations. METHODS AND FINDINGS Data were available on four 25(OH)D single nucleotide polymorphisms (SNPs; n = 82,464), plasma 25(OH)D concentrations (n = 13,565), and cases with diabetes (n = 5,565) in the China Kadoorie Biobank (CKB). The effects on risk of diabetes were assessed by a genetic score using two 25(OH)D synthesis SNPs (DHCR7-rs12785878 and CYP2R1-rs10741657), with and without the addition of SNPs affecting the transport (GC/DBP-rs2282679) and catabolism (CYP24A1-rs6013897) of 25(OH)D. The CKB results were combined in a meta-analysis of 10 studies for the 2 synthesis SNPs (n = 58,312 cases) and 7 studies for all 4 SNPs (n = 32,796 cases). Mean (SD) 25(OH)D concentration was 62 (20) nmol/l in CKB, and the per allele effects of genetic scores on 25(OH)D were 2.87 (SE 0.39) for the synthesis SNPs and 3.54 (SE 0.32) for all SNPs. A 25-nmol/l higher biochemically measured 25(OH)D was associated with a 9% (95% CI: 0%-18%) lower risk of diabetes in CKB. In a meta-analysis of all studies, a 25-nmol/l higher genetically instrumented 25(OH)D concentration was associated with a 14% (95% CI: 3%-23%) lower risk of diabetes (p = 0.01) using the 2 synthesis SNPs. An equivalent difference in 25(OH)D using a genetic score with 4 SNPs was not significantly associated with diabetes (odds ratio 8%, 95% CI: -1% to 16%, lower risk, p = 0.07), but had some evidence of pleiotropy. A limitation of the meta-analysis was the access only to study level rather than individual level data. CONCLUSIONS The concordant risks of diabetes for biochemically measured and genetically instrumented differences in 25(OH)D using synthesis SNPs provide evidence for a causal effect of higher 25(OH)D for prevention of diabetes.
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Affiliation(s)
- Ling Lu
- Clinical Trial Service Unit and Epidemiological Studies Unit, Nuffield Department of Population Health, University of Oxford, Oxford, United Kingdom
- Laboratory of Nutrition and Metabolism, Institute for Nutritional Sciences, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, China
| | - Derrick A Bennett
- Clinical Trial Service Unit and Epidemiological Studies Unit, Nuffield Department of Population Health, University of Oxford, Oxford, United Kingdom
| | - Iona Y Millwood
- Clinical Trial Service Unit and Epidemiological Studies Unit, Nuffield Department of Population Health, University of Oxford, Oxford, United Kingdom
- Medical Research Council Population Health Research Unit at the University of Oxford, Oxford, United Kingdom
| | - Sarah Parish
- Clinical Trial Service Unit and Epidemiological Studies Unit, Nuffield Department of Population Health, University of Oxford, Oxford, United Kingdom
- Medical Research Council Population Health Research Unit at the University of Oxford, Oxford, United Kingdom
| | - Mark I McCarthy
- Oxford Centre for Diabetes, Endocrinology and Metabolism, University of Oxford, Oxford, United Kingdom
- Wellcome Trust Centre for Human Genetics, Nuffield Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - Anubha Mahajan
- Wellcome Trust Centre for Human Genetics, Nuffield Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - Xu Lin
- Laboratory of Nutrition and Metabolism, Institute for Nutritional Sciences, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, China
| | - Fiona Bragg
- Clinical Trial Service Unit and Epidemiological Studies Unit, Nuffield Department of Population Health, University of Oxford, Oxford, United Kingdom
| | - Yu Guo
- Chinese Academy of Medical Sciences, Dong Cheng District, Beijing, China
| | - Michael V Holmes
- Clinical Trial Service Unit and Epidemiological Studies Unit, Nuffield Department of Population Health, University of Oxford, Oxford, United Kingdom
- Medical Research Council Population Health Research Unit at the University of Oxford, Oxford, United Kingdom
| | - Shoaib Afzal
- Department of Clinical Biochemistry, Herlev and Gentofte Hospital, Copenhagen University Hospital, Herlev, Denmark
- Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Børge G Nordestgaard
- Department of Clinical Biochemistry, Herlev and Gentofte Hospital, Copenhagen University Hospital, Herlev, Denmark
- Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Zheng Bian
- Chinese Academy of Medical Sciences, Dong Cheng District, Beijing, China
| | - Michael Hill
- Clinical Trial Service Unit and Epidemiological Studies Unit, Nuffield Department of Population Health, University of Oxford, Oxford, United Kingdom
| | - Robin G Walters
- Clinical Trial Service Unit and Epidemiological Studies Unit, Nuffield Department of Population Health, University of Oxford, Oxford, United Kingdom
| | - Liming Li
- Chinese Academy of Medical Sciences, Dong Cheng District, Beijing, China
- Department of Epidemiology and Biostatistics, Peking University Health Science Center, Peking University, Beijing, China
| | - Zhengming Chen
- Clinical Trial Service Unit and Epidemiological Studies Unit, Nuffield Department of Population Health, University of Oxford, Oxford, United Kingdom
| | - Robert Clarke
- Clinical Trial Service Unit and Epidemiological Studies Unit, Nuffield Department of Population Health, University of Oxford, Oxford, United Kingdom
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Yang L, Chen H, Zhao M, Peng P. Prognostic value of circulating vitamin D binding protein, total, free and bioavailable 25-hydroxy vitamin D in patients with colorectal cancer. Oncotarget 2018; 8:40214-40221. [PMID: 28388568 PMCID: PMC5522208 DOI: 10.18632/oncotarget.16597] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2017] [Accepted: 03/13/2017] [Indexed: 12/15/2022] Open
Abstract
Numerous studies have suggested that there was a significantly positive association between circulating total 25-hydroxyvitamin D (25(OH)D) and survival in colorectal cancer patients. Moreover, plasma vitamin D was also found significantly associated with the concentration of vitamin D binding protein (VDBP). However, there was no paper to clarify the prognostic value of VDBP, free and bioavailable 25(OH)D in colorectal carcinogenesis. The aim of this study was to comprehensively assess the prognostic value of VDBP, total, free and bioavailable 25(OH)D in stage I-III colorectal cancer patients. A total of 206 colorectal cancer patients were enrolled in this prospective study. Preoperative plasma total 25(OH)D and VDBP concentrations were measured by direct enzyme-linked immunosorbent assay, and albumin concentration was measured by Beckman automatic biochemical analyzer. Free and bioavailable 25(OH)D concentrations were calculated based on the concentrations of plasma VDBP, total 25(OH) D and albumin. X-title program was used to determine the optimal cut-off values of VDBP, total, free and bioavailable 25(OH)D. Results showed that elevated free and bioavailable 25(OH)D were significantly associated with better 5-year overall survival (OS) by univariate analysis. By multivariate cox analysis, we also found that the high level of free 25(OH)D (HR = 0.442, 95%CI = 0.238–0.819, P < 0.010) could be identified as an independent factor for better OS. In conclusion, our study suggested that higher levels of free and bioavailable 25(OH)D were associated with better OS in stage I-III colorectal cancer patients. Moreover, free 25(OH)D could be considered as an independent prognostic biomarker for OS.
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Affiliation(s)
- Lin Yang
- Department of Gastroenterology, Zhongda Hospital, School of Medicine, Southeast University, Nanjing, Jiangsu, China
| | - Hong Chen
- Department of Gastroenterology, Zhongda Hospital, School of Medicine, Southeast University, Nanjing, Jiangsu, China
| | - Miao Zhao
- Department of Gastroenterology, Zhongda Hospital, School of Medicine, Southeast University, Nanjing, Jiangsu, China
| | - Peng Peng
- Department of Gastroenterology, Zhongda Hospital, School of Medicine, Southeast University, Nanjing, Jiangsu, China
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Vitamin D Axis in Inflammatory Bowel Diseases: Role, Current Uses and Future Perspectives. Int J Mol Sci 2017; 18:ijms18112360. [PMID: 29112157 PMCID: PMC5713329 DOI: 10.3390/ijms18112360] [Citation(s) in RCA: 47] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2017] [Revised: 10/27/2017] [Accepted: 10/29/2017] [Indexed: 12/11/2022] Open
Abstract
Increasing evidence supports the concept that the vitamin D axis possesses immunoregulatory functions, with vitamin D receptor (VDR) status representing the major determinant of vitamin D’s pleiotropic effects. Vitamin D promotes the production of anti-microbial peptides, including β-defensins and cathelicidins, the shift towards Th2 immune responses, and regulates autophagy and epithelial barrier integrity. Impairment of vitamin D-mediated pathways are associated with chronic inflammatory conditions, including inflammatory bowel diseases (IBD). Interestingly, inhibition of vitamin D pathways results in dysbiosis of the gut microbiome, which has mechanistically been implicated in the development of IBD. Herein, we explore the role of the vitamin D axis in immune-mediated diseases, with particular emphasis on its interplay with the gut microbiome in the pathogenesis of IBD. The potential clinical implications and therapeutic relevance of this interaction will also be discussed, including optimizing VDR function, both with vitamin D analogues and probiotics, which may represent a complementary approach to current IBD treatments.
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Denburg MR, Bhan I. Vitamin D-Binding Protein in Health and Chronic Kidney Disease. Semin Dial 2015; 28:636-44. [PMID: 26332676 DOI: 10.1111/sdi.12422] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Vitamin D-binding protein (DBP) is a multifunctional protein that has attracted increasing interest in recent years, largely because of its potential role in modulating the activity of vitamin D. Nearly all circulating vitamin D (~85-90%) circulates bound to DBP, with a smaller proportion bound to albumin, leaving <5% circulating freely. DBP may also play roles beyond vitamin D binding, with potential roles in the immune system and elsewhere. Numerous polymorphisms of DBP exist around the world, and recent studies have identified relevance of different DBP phenotypes in determining DBP concentration and vitamin D affinity. This review focuses on the known roles of DBP in health and kidney disease, and current views on the relevance of DBP polymorphisms.
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Affiliation(s)
- Michelle R Denburg
- Departments of Pediatrics and Epidemiology, The Children's Hospital of Philadelphia, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania
| | - Ishir Bhan
- Department of Medicine, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts
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11
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Persson LJP, Aanerud M, Hiemstra PS, Michelsen AE, Ueland T, Hardie JA, Aukrust P, Bakke PS, Eagan TML. Vitamin D, vitamin D binding protein, and longitudinal outcomes in COPD. PLoS One 2015; 10:e0121622. [PMID: 25803709 PMCID: PMC4372215 DOI: 10.1371/journal.pone.0121622] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2014] [Accepted: 02/02/2015] [Indexed: 11/18/2022] Open
Abstract
Background Associations between Vitamin D3 [25(OH)D], vitamin D binding protein (VDBP) and chronic obstructive pulmonary disease (COPD) are previously reported. We aimed to further investigate these associations on longitudinal outcomes. Methods 426 COPD patients from western Norway, GOLD stage II-IV, aged 40–76, were followed every six-month from 2006 through 2009 with spirometry, bioelectrical impedance measurements and registration of exacerbation frequency. Serum 25(OH)D and VDBP levels were determined at study-entry by high-performance liquid chromatography coupled with mass spectrometry and enzyme immunoassays respectively. Yearly change in lung function and body composition was assessed by generalized estimating equations (GEE), yearly exacerbation rate by negative binomial regression models, and 5 years all-cause mortality by Cox proportional-hazard regression. Results 1/3 of the patients had vitamin D deficiency (<20ng/mL) and a greater decline in both FEV1 and FVC, compared to patients with normal levels; for FEV1 this difference only reached statistical significance in the 28 patients with the lowest levels (<10ng/mL, p = 0.01). Neither 25(OH)D nor VDBP levels predicted exacerbation rate, change in fat free mass index or risk of death. Conclusion Severe vitamin D deficiency may affect decline in lung function parameters in COPD. Neither 25(OH)D nor VDBP levels did otherwise predict markers of disease progression.
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Affiliation(s)
- Louise J. P. Persson
- Dept. of Thoracic Medicine, Haukeland University Hospital, Bergen, Norway
- * E-mail:
| | - Marianne Aanerud
- Dept. of Medicine, Haukeland University Hospital, Bergen, Norway
| | - Pieter S. Hiemstra
- Dept. of Pulmonology, Leiden University Medical Center, Leiden, The Netherlands
| | - Annika E. Michelsen
- Research Institute of Internal Medicine, Oslo University Hospital Rikshospitalet, Oslo, Norway
| | - Thor Ueland
- Research Institute of Internal Medicine, Oslo University Hospital Rikshospitalet, Oslo, Norway
- K.G. Jebsen Inflammatory Research Center, University of Oslo, Oslo, Norway
- Institute of Clinical Medicine, University of Oslo, Oslo, Norway
| | - Jon A. Hardie
- Dept. of Clinical Science, University of Bergen, Bergen, Norway
| | - Pål Aukrust
- Research Institute of Internal Medicine, Oslo University Hospital Rikshospitalet, Oslo, Norway
- Section of Clinical Immunology and Infectious Diseases, Oslo University Hospital Rikshospitalet, Oslo, Norway
- K.G. Jebsen Inflammatory Research Center, University of Oslo, Oslo, Norway
- Institute of Clinical Medicine, University of Oslo, Oslo, Norway
| | - Per S. Bakke
- Dept. of Clinical Science, University of Bergen, Bergen, Norway
| | - Tomas M. L. Eagan
- Dept. of Thoracic Medicine, Haukeland University Hospital, Bergen, Norway
- Dept. of Clinical Science, University of Bergen, Bergen, Norway
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12
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Ying HQ, Sun HL, He BS, Pan YQ, Wang F, Deng QW, Chen J, Liu X, Wang SK. Circulating vitamin D binding protein, total, free and bioavailable 25-hydroxyvitamin D and risk of colorectal cancer. Sci Rep 2015; 5:7956. [PMID: 25609140 PMCID: PMC4302314 DOI: 10.1038/srep07956] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2014] [Accepted: 12/24/2014] [Indexed: 11/29/2022] Open
Abstract
Epidemiological investigation have suggested that there is a significantly inverse association between circulating 25-hydroxyvitamin D (25(OH)D) and the risk for developing colorectal cancer (CRC) in humans. However, little is known about the role of vitamin D binding protein (VDBP) in colorectal carcinogenesis. Blood samples were collected from 212 CRC patients and 212 controls matched with age, gender and blood collection time. We used logistic regression to calculate the odds ratios and 95% confidence intervals for further estimation of the association of the quartiles of VDBP, total, free and bioavailable 25(OH)D with CRC risk. The results revealed that there was no significant association between circulating VDBP concentrations and CRC in the present study, and that a negative association existed between total 25(OH)D and the risk of CRC, which was unchanged after adjustment for VDBP. Higher levels of free and bioavailable 25(OH)D were significantly associated with decreased risk of CRC. After stratifying by VDBP, high levels of total, free and bioavailable 25(OH)D were associated significantly with decreased CRC risk among participants with circulating VDBP below the median. These findings indicate that VDBP is not directly associated with the risk of CRC, but it modulates circulating free and bioavailable 25(OH)D concentration.
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Affiliation(s)
- Hou-Qun Ying
- 1] Medical college, Southeast University, Nanjing 210009, Jiangsu, China [2] Nanjing First Hospital, Nanjing Medical University, Nanjing 210006, Jiangsu, China
| | - Hui-Ling Sun
- 1] Nanjing First Hospital, Nanjing Medical University, Nanjing 210006, Jiangsu, China [2] College of Life Sciences, Nanjing Normal University, Nanjing 210006, Jiangsu, China
| | - Bang-Shun He
- Nanjing First Hospital, Nanjing Medical University, Nanjing 210006, Jiangsu, China
| | - Yu-Qin Pan
- Nanjing First Hospital, Nanjing Medical University, Nanjing 210006, Jiangsu, China
| | - Feng Wang
- Nanjing First Hospital, Nanjing Medical University, Nanjing 210006, Jiangsu, China
| | - Qi-Wen Deng
- Nanjing First Hospital, Nanjing Medical University, Nanjing 210006, Jiangsu, China
| | - Jie Chen
- 1] Nanjing First Hospital, Nanjing Medical University, Nanjing 210006, Jiangsu, China [2] College of Life Sciences, Nanjing Normal University, Nanjing 210006, Jiangsu, China
| | - Xian Liu
- Nanjing First Hospital, Nanjing Medical University, Nanjing 210006, Jiangsu, China
| | - Shu-Kui Wang
- 1] Medical college, Southeast University, Nanjing 210009, Jiangsu, China [2] Nanjing First Hospital, Nanjing Medical University, Nanjing 210006, Jiangsu, China
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13
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Bratke K, Wendt A, Garbe K, Kuepper M, Julius P, Lommatzsch M, Virchow JC. Vitamin D binding protein and vitamin D in human allergen-induced endobronchial inflammation. Clin Exp Immunol 2014; 177:366-72. [PMID: 24730464 DOI: 10.1111/cei.12346] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/07/2014] [Indexed: 01/02/2023] Open
Abstract
Allergic asthma is a chronic disease of the airways associated with airway hyperresponsiveness, a variable degree of airflow obstruction, airway remodelling and a characteristic airway inflammation. Factors of the vitamin D axis, which include vitamin D metabolites and vitamin D binding protein (VDBP), have been linked to asthma, but only few data exist about their regulation in the lung during acute allergen-induced airway inflammation. Therefore, we analysed the regulation of factors of the vitamin D axis during the early- and late-phase reaction of allergic asthma. Fifteen patients with mild allergic asthma underwent segmental allergen challenge. VDBP was analysed in bronchoalveolar lavage fluid (BALF) and serum using the enzyme-linked immunosorbent assay (ELISA) technique. 25-hydroxyvitamin D(3)[25(OH)D(3)] and 1,25-dihydroxyvitamin D(3)[1,25(OH)(2)D(3)] were analysed by a commercial laboratory using the liquid chromatography-mass spectrometry (LC/MS) technique. VDBP (median 2·3, range 0·2-7·1 μg/ml), 25(OH)D(3) (median 0·060, range < 0·002-3·210 ng/ml) and 1,25(OH)(2)D(3) (median < 0·1, range < 0·1-2·8 pg/ml) were significantly elevated in BALF 24 h but not 10 min after allergen challenge. After correction for plasma leakage using the plasma marker protein albumin, VDBP and 25(OH)D(3) were still increased significantly while 1,25(OH)(2)D(3) was not. VDBP and 25(OH)D(3) were correlated with each other and with the inflammatory response 24 h after allergen challenge. Serum concentrations of all three factors were not influenced by allergen challenge. In conclusion, we report a significant increase in VDBP and 25(OH)D(3) in human BALF 24 h after allergen challenge, suggesting a role for these factors in the asthmatic late-phase reaction.
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Affiliation(s)
- K Bratke
- Department of Pneumology, University of Rostock, Rostock, Germany
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14
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Trujillo G, Habiel DM, Ge L, Ramadass M, Cooke NE, Kew RR. Neutrophil recruitment to the lung in both C5a- and CXCL1-induced alveolitis is impaired in vitamin D-binding protein-deficient mice. THE JOURNAL OF IMMUNOLOGY 2013; 191:848-56. [PMID: 23752613 DOI: 10.4049/jimmunol.1202941] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Knowledge of how neutrophils respond to chemotactic signals in a complex inflammatory environment is not completely understood. Moreover, even less is known about factors in physiological fluids that regulate the activity of chemoattractants. The vitamin D-binding protein (DBP) has been shown to significantly enhance chemotaxis to complement activation peptide C5a using purified proteins in vitro, and by ex vivo depletion of DBP in physiological fluids, but this function has not been determined in vivo. DBP null ((-/-)) mice were used to investigate how a systemic absence of this plasma protein affects leukocyte recruitment in alveolitis models of lung inflammation. DBP(-/-) mice had significantly reduced (~50%) neutrophil recruitment to the lungs compared with their wild-type DBP(+/+) counterparts in three different alveolitis models, two acute and one chronic. The histology of DBP(-/-) mouse lungs also showed significantly less injury than wild-type animals. The chemotactic cofactor function of DBP appears to be selective for neutrophil recruitment, but, in contrast to previous in vitro results, in vivo DBP can enhance the activity of other chemoattractants, including CXCL1. The reduced neutrophil response in DBP(-/-) mice could be rescued to wild-type levels by administering exogenous DBP. Finally, in inflammatory fluids, DBP binds to G-actin released from damaged cells, and this complex may be the active chemotactic cofactor. To our knowledge, results show for the first time that DBP is a significant chemotactic cofactor in vivo and not specific for C5a, suggesting that this ubiquitous plasma protein may have a more significant role in neutrophil recruitment than previously recognized.
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Affiliation(s)
- Glenda Trujillo
- Department of Pathology, Stony Brook University School of Medicine, Stony Brook, NY 11794, USA
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15
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Teles LMB, Aquino EN, Neves ACD, Garcia CHS, Roepstorff P, Fontes B, Castro MS, Fontes W. Comparison of the neutrophil proteome in trauma patients and normal controls. Protein Pept Lett 2012; 19:663-72. [PMID: 22519539 PMCID: PMC3382372 DOI: 10.2174/092986612800493977] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2011] [Revised: 12/12/2011] [Accepted: 12/14/2011] [Indexed: 01/11/2023]
Abstract
Background: Neutrophils have an impressive array of microbicidal weapons, and in the presence of a pathogen, progress from a quiescent state in the bloodstream to a completely activated state. Failure to regulate this activation, for example, when the blood is flooded with cytokines after severe trauma, causes inappropriate neutrophil activation that paradoxically, is associated with tissue and organ damage. Acidic proteomic maps of quiescent human neutrophils were analyzed and compared to those of activated neutrophils from severe trauma patients. The analysis revealed 114 spots whose measured volumes differed between activated and quiescent neutrophils, with 27 upregulated and 87 downregulated in trauma conditions. Among the identified proteins, grancalcin, S100-A9 and CACNB2 reinforce observed correlations between motility and ion flux, ANXA3, SNAP, FGD1 and Zfyve19 are involved in vesicular transport and exocytosis, and GSTP1, HSPA1 HSPA1L, MAOB, UCH-L5, and PPA1 presented evidence that activated neutrophils may have diminished protection against oxidative damage and are prone to apoptosis. These are discussed, along with proteins involved in cytoskeleton reorganization, reactive oxygen species production, and ion flux. Proteins such as Zfyve19, MAOB and albumin- like protein were described for the first time in the neutrophil. In this work we achieved the identification of several proteins potentially involved in inflammatory signaling after trauma, as well as proteins described for the first time in neutrophils. | ![]() |
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Affiliation(s)
- Liz M B Teles
- Laboratory of Biochemistry and Protein Chemistry, Cell Biology Department, University of Brasília, Brasilia, DF, Brazil. CEP 70910-900
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16
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Garg M, Lubel JS, Sparrow MP, Holt SG, Gibson PR. Review article: vitamin D and inflammatory bowel disease--established concepts and future directions. Aliment Pharmacol Ther 2012; 36:324-44. [PMID: 22686333 DOI: 10.1111/j.1365-2036.2012.05181.x] [Citation(s) in RCA: 70] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/18/2012] [Revised: 05/11/2012] [Accepted: 05/25/2012] [Indexed: 02/06/2023]
Abstract
BACKGROUND Understanding of the role of vitamin D in health and disease has increased markedly in the past decade, with its involvement extending well beyond traditional roles in calcium and phosphate homeostasis and musculoskeletal health. This conceptual expansion has been underpinned by identification and exploration of components of this axis including vitamin D-binding protein, key enzymes and receptors in multiple cell types, and a greater recognition of nonclassical autocrine and paracrine effects. Its influence in IBD remains uncertain. AIM To review the role of vitamin D in bone health, immune regulation and cancer prevention in IBD, and to outline practical issues and limitations of its use. METHODS An extensive online literature review including PubMed and Medline. RESULTS In patients with IBD, the vitamin D axis provides an important and often underutilised pathway to preserving bone health. Furthermore, an exciting body of clinical and basic science research demonstrates that these pathways may have an integral part to play in regulation of the immune response in IBD, through effects on the intestinal barrier, antigen presenting cells and adaptive T cells. The possibility of chemoprevention requires further study. The optimal target level of 25-hydroxy vitamin D in patients with IBD is currently uncertain, as is the best therapeutic modality. CONCLUSIONS Study of vitamin D pathways may result in the development of relatively inexpensive therapeutic options to optimise patient outcomes. Further prospective clinical research is required to address efficacy and long-term safety.
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Affiliation(s)
- M Garg
- Department of Gastroenterology & Hepatology, Eastern Health, Box Hill, Vic., Australia.
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17
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Chun RF. New perspectives on the vitamin D binding protein. Cell Biochem Funct 2012; 30:445-56. [DOI: 10.1002/cbf.2835] [Citation(s) in RCA: 176] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2012] [Revised: 03/09/2012] [Accepted: 03/28/2012] [Indexed: 12/23/2022]
Affiliation(s)
- Rene F. Chun
- UCLA/Orthopaedic Hospital; Department of Orthopaedic Surgery, Orthopaedic Hospital Research Center, David Geffen School of Medicine at UCLA; Los Angeles; California; USA
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18
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Demkow U, van Overveld FJ. Role of elastases in the pathogenesis of chronic obstructive pulmonary disease: implications for treatment. Eur J Med Res 2011; 15 Suppl 2:27-35. [PMID: 21147616 PMCID: PMC4360323 DOI: 10.1186/2047-783x-15-s2-27] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Neutrophil elastase, metalloproteinases, and their inhibitors play an important role in the development of chronic obstructive pulmonary disease (COPD), resulting in extensive tissue damage and malfunctioning of the airways. Nearly fifty years after the protease-antiprotease imbalance hypothesis has been suggested for the cause of emphysema, it is still appealing, but it does not explain the considerable variation in the clinical expressions of emphysema. However, there are many recent research findings to support the imbalance hypothesis as will be shown in this review. Although limited, there might be openings for the treatment of the disease.
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Affiliation(s)
- Urszula Demkow
- Dept. Lab. Diagn. and Clin. Immunol., Warsaw Medical University, Warsaw, Poland.
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19
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The emerging role of vitamin D binding protein in multiple sclerosis. J Neurol 2010; 258:353-8. [DOI: 10.1007/s00415-010-5797-8] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2010] [Revised: 09/20/2010] [Accepted: 10/07/2010] [Indexed: 01/22/2023]
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20
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Zhang J, Habiel DM, Ramadass M, Kew RR. Identification of two distinct cell binding sequences in the vitamin D binding protein. BIOCHIMICA ET BIOPHYSICA ACTA 2010; 1803:623-9. [PMID: 20211661 PMCID: PMC2856814 DOI: 10.1016/j.bbamcr.2010.02.010] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/05/2010] [Revised: 02/22/2010] [Accepted: 02/24/2010] [Indexed: 02/04/2023]
Abstract
The vitamin D binding protein (DBP) is a multifunctional, albumin-like plasma protein that often requires cell surface binding to mediate some of its diverse functions. DBP binds to several different molecules on the external face of the plasma membrane indicating that it may possess distinct cell binding sequences. In this report, surface plasmon resonance was utilized to evaluate the relative binding of the human myeloid cell line U937 to immobilized recombinant expressed DBP in order to identify cell localization sequences. U937 cells showed robust binding to immobilized native DBP, but essentially no interaction when sensor chips were coated with beta(2)-microglobulin or BSA. The cell-DBP interaction was completely eliminated if cells were pretreated with soluble DBP. Recombinant DBP domains and truncated domains were next evaluated to determine the location of cell binding regions. Domains I (amino acids 1-191) and III (379-458), but not domain II (192-378), could support cell binding. Further evaluation of domain I, using truncated proteins and overlapping peptides, demonstrated that a single amino acid sequence, residues 150-172 (NYGQAPLSLLVSYTKSYLSMVGS), mediated cell binding. The domain III cell binding region was investigated using truncated versions of domain III fused to full-length domain II that served as a scaffold. These experiments indicated that the cell binding sequence is located in the first portion of that domain (379-402: ELSSFIDKGQELCADYSENTFTEY). Overlapping peptides spanning this sequence could partially block cell binding only when used in combination. We conclude that DBP contains two cell localization sequences that may be required for some of the multiple functions of this protein.
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Affiliation(s)
- Jianhua Zhang
- Department of Pathology, Stony Brook University School of Medicine, Stony Brook, NY 11794-8691, USA
| | - David M. Habiel
- Department of Pathology, Stony Brook University School of Medicine, Stony Brook, NY 11794-8691, USA
| | - Mahalakshmi Ramadass
- Department of Pathology, Stony Brook University School of Medicine, Stony Brook, NY 11794-8691, USA
| | - Richard R. Kew
- Department of Pathology, Stony Brook University School of Medicine, Stony Brook, NY 11794-8691, USA
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21
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Swamy N, Ray R. Fatty acid-binding site environments of serum vitamin D-binding protein and albumin are different. Bioorg Chem 2008; 36:165-8. [DOI: 10.1016/j.bioorg.2008.02.002] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2008] [Revised: 02/13/2008] [Accepted: 02/14/2008] [Indexed: 11/27/2022]
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High C5a levels are associated with increased mortality in sepsis patients--no enhancing effect by actin-free Gc-globulin. Clin Biochem 2008; 41:974-80. [PMID: 18538666 DOI: 10.1016/j.clinbiochem.2008.05.005] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2008] [Accepted: 05/12/2008] [Indexed: 11/24/2022]
Abstract
BACKGROUND Immune paralysis of phagocytic cells due to excess of the complement activation product C5a has been proposed as a critical pathomechanism in sepsis. In vitro studies suggest an interaction of C5a with Group-specific globulin (Gc-globulin). STUDY OBJECTIVES To examine the predictive value of serum concentrations of both, C5a and actin-free Gc-globulin, and their ratio for prognosis (mortality) of critically ill patients. PATIENTS 154 critically ill (septic and non-septic) adult patients admitted to a Medical ICU and 38 healthy controls. MEASUREMENTS Actin-free Gc-globulin and C5a were measured on ICU admission, alongside extensive laboratory, clinical and prospective outcome measures. RESULTS Actin-free Gc-globulin and C5a serum concentrations were significantly reduced in critically ill patients compared with healthy controls. C5a levels, but not actin-free Gc-globulin, were significantly lower in patients with sepsis (n=112) than in critically ill patients without sepsis (n=42). C5a serum level was a prognostic parameter in patients with sepsis: High C5a levels were associated with increased mortality (at ICU and during follow-up). Although C5a and actin-free Gc-globulin were positively correlated, increasing serum concentrations of actin-free Gc-globulin did not enhance the C5a dependent effects in terms of prognosis or mortality in septic patients. CONCLUSIONS Investigation for C5a and/or actin-free Gc-globulin serum levels upon admission to the ICU may be helpful diagnostic tools. In patients with sepsis, C5a levels are an independent predictor of prognosis. However, different to pre-existing in vitro data, a clinically relevant interaction between actin-free Gc-globulin and C5a in terms of prognosis in severe inflammatory conditions is not given.
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Silva J, López-Farré AJ, Mateos-Cáceres PJ, González A, Maroto L, Macaya C, Rodríguez E. Proteomic pattern of plasma in off-pump coronary artery bypass surgery. Clin Chem Lab Med 2008; 46:1074-84. [DOI: 10.1515/cclm.2008.234] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Gressner OA, Lahme B, Gressner AM. Gc-globulin (vitamin D binding protein) is synthesized and secreted by hepatocytes and internalized by hepatic stellate cells through Ca(2+)-dependent interaction with the megalin/gp330 receptor. Clin Chim Acta 2007; 390:28-37. [PMID: 18194670 DOI: 10.1016/j.cca.2007.12.011] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2007] [Revised: 12/10/2007] [Accepted: 12/10/2007] [Indexed: 01/22/2023]
Abstract
BACKGROUND Gc-globulin or vitamin D binding protein is a highly expressed, multifunctional and polymorphic serum protein, which also serves as the major transporter for vitamin D metabolites in the circulation. The present study was performed to analyze the interaction between gc-globulin of hepatocytes and hepatic stellate cells, the most important fat-/retinol-storing cell type in the liver, which spontaneously transdifferentiates to myofibroblasts in culture. METHODS Hepatic stellate cells and hepatocytes were isolated by the pronase/collagenase reperfusion method, hepatocytes by collagenase reperfusion of the organ. Gc-globulin expression was monitored by immunocytochemistry, immunoblotting, RT-PCR, metabolic labelling with [(35)S]-methionine, and its intracellular binding to alpha-smooth-muscle actin was investigated by co-immunoprecipitation. Cytoskeletal stainings of gc-globulin and alpha-smooth-muscle actin in hepatic stellate cells and the identification of the receptors megalin/gp330, HCAM/CD44, cubilin and annexin A2 were performed with confocal immunocytochemistry, immunoblotting and/or FACS-analysis. RESULTS Hepatocytes synthesize and secrete gc-globulin as shown by RT-PCR and [(35)S]-methionine labelling, which could be suppressed by cycloheximide. Also, a strong signal for gc-globulin was detected in the immunoblot of native hepatic stellate cell lysates. However, no mRNA for gc-globulin was found in this cell type, which suggests no active synthesis by hepatic stellate cells. Hepatic stellate cells were tested positively for the presence of known gc-globulin interacting receptors megalin/gp330, HCAM/CD44, cubilin and annexin A2. Inhibition of the megalin/gp330 receptor by a competitive, neutralizing antibody resulted in decreased intracellular availability of gc-globulin in hepatic stellate cells. The latter effect was enhanced by additional incubation of hepatic stellate cells with EDTA for complexing Ca(2+), suggesting a Ca(2+)-dependent internalization of gc-globulin into hepatic stellate cells via the megalin/gp300 receptor. This was supported by confocal microscopy which showed a co-localization of gc-globulin with the multifunctional megalin/gp330 receptor on this cell type. Inside hepatic stellate cells, a linkage between gc-globulin and alpha-smooth muscle actin filaments of hepatic stellate cells was detected by immunocytochemistry. Intracellular binding of gc-globulin to alpha-smooth-muscle actin filaments was confirmed by co-immunoprecipitation. CONCLUSION We give evidence to the expression of the megalin/gp330 receptor on hepatic stellate cells and that this receptor is involved in the Ca(2+)-dependent internalization of gc-globulin into hepatic stellate cells, a protein synthesized and secreted into the extracellular space and circulation by hepatocytes. Inside hepatic stellate cells, it co-localizes with and binds to alpha-smooth muscle actin filaments. Under consideration of the available literature, these findings propose a participation of gc-globulin in hepatic vitamin D metabolism as well as in hepatic stellate cell stability and apoptosis as important mechanisms of liver regeneration.
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Affiliation(s)
- Olav A Gressner
- Institute of Clinical Chemistry and Pathobiochemistry, RWTH-University Hospital, Aachen, Germany.
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25
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Ray A, Swamy N, Ray R. Cross-talk among structural domains of human DBP upon binding 25-hydroxyvitamin D. Biochem Biophys Res Commun 2007; 365:746-50. [PMID: 18035050 DOI: 10.1016/j.bbrc.2007.11.033] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2007] [Accepted: 11/08/2007] [Indexed: 11/26/2022]
Abstract
Serum vitamin D-binding protein (DBP) is structurally very similar to serum albumin (ALB); both have three distinct structural domains and high cysteine-content. Yet, functionally they are very different. DBP possesses high affinity for vitamin D metabolites and G-actin, but ALB does not. It has been suggested that there may be cross-talk among the domains so that binding of one ligand may influence the binding of others. In this study we have employed 2-p-toluidinyl-6-sulfonate (TNS), a reporter molecule that fluoresces upon binding to hydrophobic pockets of DBP. We observed that recombinant domain III possesses strong binding for TNS, which is not influenced by 25-hydroxyvitamin D(3) (25-OH-D(3)), yet TNS fluorescence of the whole protein is quenched by 25-OH-D(3). These results provide a direct evidence of cross-talk among the structural domains of DBP.
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Affiliation(s)
- Arjun Ray
- Bioorganic Chemistry & Structural Biology, Department of Medicine, Boston University School of Medicine, 85 East Newton Street, Boston, MA 02118, USA
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Gressner O, Meier U, Hillebrandt S, Wasmuth HE, Köhl J, Sauerbruch T, Lammert F. Gc-globulin concentrations and C5 haplotype-tagging polymorphisms contribute to variations in serum activity of complement factor C5. Clin Biochem 2007; 40:771-5. [PMID: 17428459 DOI: 10.1016/j.clinbiochem.2007.02.001] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2006] [Revised: 02/03/2007] [Accepted: 02/06/2007] [Indexed: 12/11/2022]
Abstract
OBJECTIVES To investigate the role of Gc-globulin and C5 gene variants as co-factors in the regulation of profibrogenic C5 serum activities. DESIGN Retrospective clinical investigation with 100 healthy probands. Genomic DNA was isolated from whole blood and examined for the human C5 htSNPs rs17611 and rs2300929. Actin-free Gc-globulin-, total Gc-globulin- and total C5-concentrations in serum were measured using ELISA assays; C5 activities in serum were determined using radial immunodiffusion. RESULTS C5 serum concentrations were significantly elevated in individuals carrying at least one profibrogenic allele of the C5 htSNP rs17611, but no association between C5 htSNPs and C5 serum activities was detected, albeit C5 activities correlated positively with C5 concentrations in serum. However, C5 activities were also positively correlated with total and actin-free Gc-globulin concentrations. CONCLUSION Our findings indicate that C5 gene variants and Gc-globulin levels co-define the proinflammatory and profibrogenic effects of C5 in patients at-risk for progression of liver fibrosis.
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Affiliation(s)
- Olav Gressner
- Department of Internal Medicine I, University Hospital Bonn, University of Bonn, Sigmund-Freud-Str 25, Bonn, Germany
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Abstract
BACKGROUND Gc-globulin (vitamin D-binding protein) appears to have important functions in addition to its role as a carrier of vitamin D. APPROACH We reviewed recent studies focusing on the pathophysiologic functions and clinical significance of Gc-globulin. RESULTS Serum concentrations of Gc-globulin, as determined by immunoassay techniques, are decreased in severe injury. The extent of the decrease may have prognostic significance for patient outcomes. Clinical studies and animal models have shown that Gc-globulin has an important role in the clearance of procoagulant actin from the circulation after its release during cell necrosis and tissue injury. Gc-globulin has other potential roles in responses to acute tissue injury through conversion to a macrophage-activating factor, neutrophil chemotactic activity, and enhancement of C5a-mediated signaling. CONCLUSION Considering the important physiologic roles of Gc-globulin in responses to tissue injury, such as clearance of actin, measurement of Gc-globulin may have value in directing the care of patients in many clinical disorders.
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Affiliation(s)
- Ursula Meier
- Institute of Clinical Chemistry and Pathobiochemistry and Central Laboratory, Rheinisch-Westfälische Technische Hochschule (RWTH)-University Hospital Aachen, Aachen, Germany.
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Korytina GF, Akhmadishina LZ, Yanbaeva DG, Victorova TV. Genotypes of the vitamin D-binding protein gene in patients with chronic obstructive pulmonary disease and in the healthy population of the Republic Bashkortostan. Mol Biol 2006. [DOI: 10.1134/s002689330602004x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Shah AB, DiMartino SJ, Trujillo G, Kew RR. Selective inhibition of the C5a chemotactic cofactor function of the vitamin D binding protein by 1,25(OH)2 vitamin D3. Mol Immunol 2005; 43:1109-15. [PMID: 16115686 PMCID: PMC1403830 DOI: 10.1016/j.molimm.2005.07.023] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2005] [Indexed: 10/25/2022]
Abstract
The Vitamin D binding protein (DBP) is a multifunctional plasma protein that can significantly enhance the chemotactic response to complement fragment C5a. The chemotactic cofactor function of DBP requires cell surface binding in order to mediate this process. The goal of this study was to investigate the effect of ligating DBP with its two primary physiological ligands, Vitamin D and G-actin, on both binding to neutrophils and the ability to enhance chemotaxis to C5a. There was no difference in neutrophil binding between of the holo (bound) forms versus the apo (unbound) form of radioiodinated DBP, indicating that the cell binding region of DBP is likely distinct from the Vitamin D sterol and G-actin binding sites. Likewise, G-actin, 25(OH)D3, and G-actin plus 25(OH)D3 bound to DBP did not alter its capacity to enhance chemotaxis toward C5a. However, the active form of Vitamin D (1,25(OH)2D3) completely eliminated the chemotactic cofactor function of DBP. Dose-response curves demonstrated that as little as 1pM 1,25(OH)2D3 significantly inhibited chemotaxis enhancement. Moreover, at physiological concentrations 1,25(OH)2D3 needs to be bound to DBP to mediate the inhibitory effect. Neutrophil chemotaxis to optimal concentrations of C5a, formyl peptide, CXCL8 or leukotriene B4 was not altered by 1,25(OH)2D3, indicating that the active vitamin does not have a global inhibitory effect on neutrophil chemotaxis. Finally, inhibition of cell surface alkaline phosphatase (AP) with sodium orthovanadate completely reversed the inhibitory effect of 1,25(OH)2D3. These results indicate that the cell binding and co-chemotactic functions of DBP are not altered when the protein binds G-actin and/or Vitamin D. Furthermore, the co-chemotactic signal from DBP can be eliminated or counteracted by 1,25(OH)2D3.
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Affiliation(s)
| | | | | | - Richard R. Kew
- Address all correspondence to Dr. Richard R. Kew, Department of Pathology, Stony Brook University, Stony Brook, NY 11794-8691. Tel: (631)444-3941, Fax: (631)444-3424. E-mail:
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