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Matias P, Ávila G, Ferreira AC, Laranjinha I, Ferreira A. Hypomagnesemia: a potential underlooked cause of persistent vitamin D deficiency in chronic kidney disease. Clin Kidney J 2023; 16:1776-1785. [PMID: 37915933 PMCID: PMC10616498 DOI: 10.1093/ckj/sfad123] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2022] [Indexed: 11/03/2023] Open
Abstract
Magnesium and vitamin D play important roles in most cells of the body. These nutrients act in a coordinated fashion to maintain physiologic functions of various organs, and their abnormal balance could adversely affect these functions. Therefore, deficient states of both nutrients may lead to several chronic medical conditions and increased cardiovascular and all-cause mortality. Chronic kidney disease (CKD) patients have altered metabolism of both magnesium and vitamin D. Some studies indicate that magnesium could have a role in the synthesis and metabolism of vitamin D, and that magnesium supplementation substantially reversed the resistance to vitamin D treatment in some clinical situations. Recent observational studies also found that magnesium intake significantly interacted with vitamin D status and, particularly with the risk of cardiovascular mortality. It is therefore essential to ensure adequate levels of magnesium to obtain the optimal benefits of vitamin D supplementation in CKD patients. In this review, we discuss magnesium physiology, magnesium and vitamin D metabolism in CKD, potential metabolic interactions between magnesium and vitamin D and its clinical relevance, as well as the possible role of magnesium supplementation to assure adequate vitamin D levels.
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Affiliation(s)
- Patrícia Matias
- Nephrology Department, Hospital de Santa Cruz - Centro Hospitalar de Lisboa Ocidental, Carnaxide, Portugal
- NOVA Medical School, Lisbon, Portugal
| | - Gonçalo Ávila
- Nephrology Department, Hospital de Santa Cruz - Centro Hospitalar de Lisboa Ocidental, Carnaxide, Portugal
| | - Ana Carina Ferreira
- NOVA Medical School, Lisbon, Portugal
- Nephrology department, Hospital Curry Cabral - Centro Hospitalar e Universitário de Lisboa Central, Lisbon, Portugal
| | - Ivo Laranjinha
- Nephrology Department, Hospital de Santa Cruz - Centro Hospitalar de Lisboa Ocidental, Carnaxide, Portugal
| | - Aníbal Ferreira
- NOVA Medical School, Lisbon, Portugal
- Nephrology department, Hospital Curry Cabral - Centro Hospitalar e Universitário de Lisboa Central, Lisbon, Portugal
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2
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Ureña Torres PA, Souberbielle JC, Solal MC. Bone Fragility in Chronic Kidney Disease Stage 3 to 5: The Use of Vitamin D Supplementation. Metabolites 2022; 12:metabo12030266. [PMID: 35323709 PMCID: PMC8953916 DOI: 10.3390/metabo12030266] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2022] [Revised: 03/10/2022] [Accepted: 03/17/2022] [Indexed: 12/02/2022] Open
Abstract
Frequently silent until advanced stages, bone fragility associated with chronic kidney disease-mineral and bone disease (CKD-MBD) is one of the most devastating complications of CKD. Its pathophysiology includes the reduction of active vitamin D metabolites, phosphate accumulation, decreased intestinal calcium absorption, renal alpha klotho production, and elevated fibroblast growth factor 23 (FGF23) levels. Altogether, these factors contribute firstly to secondary hyperparathyroidism, and ultimately, to micro- and macrostructural bone changes, which lead to low bone mineral density and an increased risk of fracture. A vitamin D deficiency is common in CKD patients, and low circulating 25(OH)D levels are invariably associated with high serum parathyroid hormone (PTH) levels as well as with bone mineralization defects, such as osteomalacia in case of severe forms. It is also associated with a variety of non-skeletal diseases, including cardiovascular disease, diabetes mellitus, multiple sclerosis, cancer, and reduced immunological response. Current international guidelines recommend supplementing CKD patients with nutritional vitamin D as in the general population; however, there is no randomized clinical trial (RCT) evaluating the effect of vitamin D (or vitamin D+calcium) supplementation on the risk of fracture in the setting of CKD. It is also unknown what level of circulating 25(OH)D would be sufficient to prevent bone abnormalities and fractures in these patients. The impact of vitamin D supplementation on other surrogate endpoints, including bone mineral density and bone-related circulating biomarkers (PTH, FGF23, bone-specific alkaline phosphatase, sclerostin) has been evaluated in several RTCs; however, the results were not always translated into an improvement in long-term outcomes, such as reduced fracture risk. This review provides a brief and comprehensive update on CKD-related bone fragility and the use of natural vitamin D supplementation in these patients.
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Affiliation(s)
- Pablo Antonio Ureña Torres
- Department of Dialysis AURA Nord Saint Ouen, 12, Rue Anselme, 93400 Saint Ouen, France
- Department of Renal Physiology, Necker Hospital, University of Paris Descartes, 75015 Paris, France;
- Correspondence: (P.A.U.T.); (M.C.S.)
| | - Jean Claude Souberbielle
- Department of Renal Physiology, Necker Hospital, University of Paris Descartes, 75015 Paris, France;
| | - Martine Cohen Solal
- Bioscar INSERM U1132, Department of Rheumatology, Université de Paris, Hôpital Lariboisière, 75010 Paris, France
- Correspondence: (P.A.U.T.); (M.C.S.)
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3
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Biruete A, Shin A, Kistler BM, Moe SM. Feeling gutted in chronic kidney disease (CKD): Gastrointestinal disorders and therapies to improve gastrointestinal health in individuals CKD, including those undergoing dialysis. Semin Dial 2021:10.1111/sdi.13030. [PMID: 34708456 PMCID: PMC9043041 DOI: 10.1111/sdi.13030] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2021] [Accepted: 09/21/2021] [Indexed: 12/15/2022]
Abstract
Chronic kidney disease (CKD) affects 9.1% of the population worldwide. CKD may lead to structural and functional gastrointestinal alterations, including impairment in the intestinal barrier, digestion and absorption of nutrients, motility, and changes to the gut microbiome. These changes can lead to increased gastrointestinal symptoms in people with CKD, even in early grades of kidney dysfunction. Gastrointestinal symptoms have been associated with lower quality of life and reduced nutritional status. Therefore, there has been considerable interest in improving gastrointestinal health in this clinical population. Gastrointestinal health can be influenced by lifestyle and medications, particularly in advanced grades of kidney dysfunction. Therapies focused on gastrointestinal health have been studied, including the use of probiotics, prebiotics, and synbiotics, yielding limited and conflicting results. This review summarizes the alterations in the gastrointestinal tract structure and function and provides an overview of potential nutritional interventions that kidney disease professionals can provide to improve gastrointestinal health in individuals with CKD.
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Affiliation(s)
- Annabel Biruete
- Department of Nutrition and Dietetics, Indiana University-Purdue University Indianapolis, Indianapolis, Indiana, USA
- Division of Nephrology, Department of Medicine, Indiana University School of Medicine, Indianapolis, Indiana, USA
| | - Andrea Shin
- Division of Gastroenterology and Hepatology, Department of Medicine, Indiana University School of Medicine, Indianapolis, Indiana, USA
| | - Brandon M. Kistler
- Department of Nutrition and Health Science, Ball State University, Muncie, Indiana, USA
| | - Sharon M. Moe
- Division of Nephrology, Department of Medicine, Indiana University School of Medicine, Indianapolis, Indiana, USA
- Department of Anatomy, Cell Biology, and Anatomy, Indiana University School of Medicine, Indianapolis, Indiana, USA
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4
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Abstract
Context Vitamin D is frequently prescribed as a supplement, yet its absorption remains poorly understood. Objective This systematic review was performed to evaluate data on mechanisms involved in the intestinal absorption of vitamin D. Data Sources PubMed, Embase, and Cochrane Library databases were searched. Study Selection The following studies were included: experimental laboratory studies of vitamin D absorption through the enterocyte brush-border membrane; absorption tests that used radiolabeled vitamin D; and clinical trials in adults that investigated a single dose of cholecalciferol or ergocalciferol and reported at least 2 measurements of serum cholecalciferol, ergocalciferol, or 25-hydroxyvitamin D. Data Extraction From 2069 articles identified, 46 met the inclusion criteria. Results Different methods were employed to evaluate vitamin D absorption. Recent research suggests that vitamin D absorption is not an exclusive simple diffusion process. Vitamin D was better absorbed when it was consumed with fat-containing meals, but absorption also occurred without fat or oily vehicles. Factors that modified cholesterol absorption also altered vitamin D absorption. Conclusion Vitamin D is probably absorbed through passive diffusion and a mechanism involving membrane carriers, especially cholesterol transporters, although data remain scarce. Some data suggest that fat, when consumed concomitantly with vitamin D, improves vitamin D absorption.
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Affiliation(s)
- Mariana Costa Silva
- School of Medicine, Postgraduate Program in Medicine: Medical Sciences, Federal University of Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brazil
| | - Tania Weber Furlanetto
- School of Medicine, Postgraduate Program in Medicine: Medical Sciences, Federal University of Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brazil.,Internal Medicine Division, Hospital de Clinicas de Porto Alegre, Porto Alegre, Brazil
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5
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Cardoso MP, Pereira LAL. Native vitamin D in pre-dialysis chronic kidney disease. Nefrologia 2018; 39:18-28. [PMID: 30274806 DOI: 10.1016/j.nefro.2018.07.004] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2018] [Accepted: 07/12/2018] [Indexed: 02/08/2023] Open
Abstract
Chronic kidney disease patients have a high prevalence of vitamin D insufficiency/deficiency. Vitamin D deficiency has been associated with a variety of bone, metabolic and cardiovascular disorders. However, the role of native vitamin D supplementation (ergocalciferol, cholecalciferol or calcifediol) remains unclear in chronic kidney disease (CKD), particularly in the pre-dialytic phase. Several international guidelines have been developed on CKD-Mineral and Bone Disorder, but the optimal strategy for native vitamin D supplementation and its clinical benefit remains a subject of debate in the scientific community. This paper aims to review the available literature, including randomized clinical trials that evaluated the effects of native vitamin D supplementation on pre-dialysis CKD on biochemical and clinically relevant outcomes.
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Affiliation(s)
- Mariana P Cardoso
- Faculty of Medicine of University of Porto, Al. Prof. Hernâni Monteiro, 4200-451 Porto, Portugal.
| | - Luciano A L Pereira
- Institute of Investigation and Innovation in Health, University of Porto, Rua Alfredo Allen, 208, 4200-135 Porto, Portugal; Nephrology and Infeciology Group, INEB-National Institute of Biomedical Engineer, University of Porto, Rua Alfredo Allen, 208, 4200-135 Porto, Portugal; Department of Nephrology, São João Hospital Center, Al. Prof. Hernâni Monteiro, 4200-451 Porto, Portugal
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Franca Gois PH, Wolley M, Ranganathan D, Seguro AC. Vitamin D Deficiency in Chronic Kidney Disease: Recent Evidence and Controversies. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2018; 15:E1773. [PMID: 30126163 PMCID: PMC6121405 DOI: 10.3390/ijerph15081773] [Citation(s) in RCA: 58] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/18/2018] [Revised: 08/14/2018] [Accepted: 08/16/2018] [Indexed: 12/16/2022]
Abstract
Vitamin D (VD) is a pro-hormone essential for life in higher animals. It is present in few types of foods and is produced endogenously in the skin by a photochemical reaction. The final step of VD activation occurs in the kidneys involving a second hydroxylation reaction to generate the biologically active metabolite 1,25(OH)₂-VD. Extrarenal 1α-hydroxylation has also been described to have an important role in autocrine and paracrine signaling. Vitamin D deficiency (VDD) has been in the spotlight as a major public healthcare issue with an estimated prevalence of more than a billion people worldwide. Among individuals with chronic kidney disease (CKD), VDD prevalence has been reported to be as high as 80%. Classically, VD plays a pivotal role in calcium and phosphorus homeostasis. Nevertheless, there is a growing body of evidence supporting the importance of VD in many vital non-skeletal biological processes such as endothelial function, renin-angiotensin-aldosterone system modulation, redox balance and innate and adaptive immunity. In individuals with CKD, VDD has been associated with albuminuria, faster progression of kidney disease and increased all-cause mortality. Recent guidelines support VD supplementation in CKD based on extrapolation from cohorts conducted in the general population. In this review, we discuss new insights on the multifactorial pathophysiology of VDD in CKD as well as how it may negatively modulate different organs and systems. We also critically review the latest evidence and controversies of VD monitoring and supplementation in CKD patients.
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Affiliation(s)
- Pedro Henrique Franca Gois
- Kidney Health Service, Royal Brisbane and Women's Hospital, Herston QLD 4029, Australia.
- Medical School, University of Queensland, Herston QLD 4029, Australia.
| | - Martin Wolley
- Kidney Health Service, Royal Brisbane and Women's Hospital, Herston QLD 4029, Australia.
- Medical School, University of Queensland, Herston QLD 4029, Australia.
| | - Dwarakanathan Ranganathan
- Kidney Health Service, Royal Brisbane and Women's Hospital, Herston QLD 4029, Australia.
- Medical School, University of Queensland, Herston QLD 4029, Australia.
| | - Antonio Carlos Seguro
- Laboratory of Medical Research-LIM12, Nephrology Department, University of São Paulo School of Medicine, São Paulo, CEP 01246-903, Brazil.
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Han N, Hong SH, Kim YS, Kim DK, Kim IW, Ji E, Oh JM. Effect of additive calcium administration on FGF23 levels in patients with mild chronic kidney disease treated with calcitriol: a randomized, open-labeled clinical trial. Ther Clin Risk Manag 2017; 13:999-1007. [PMID: 28860784 PMCID: PMC5565373 DOI: 10.2147/tcrm.s142564] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
BACKGROUND The purpose of the present study was to determine the effect of additional calcium carbonate treatment on fibroblast growth factor 23 (FGF23) levels in patients treated with calcitriol. METHODS In this randomized, open-labeled, and parallel-group study, a total of 30 patients with early chronic kidney disease (CKD) and vitamin D deficiency were randomly assigned to two groups and received interventions for 8 weeks: 1) a combination of calcium carbonate and calcitriol group; and 2) calcitriol only group. The primary outcome was the difference in percentage change of serum FGF23 levels from baseline between the two groups. Secondary end points included the changes in serum levels of calcium, phosphate, parathyroid hormone (PTH), and 25-hydroxyvitamin D3 (25(OH)D) from baseline. RESULTS Serum FGF23 levels were more elevated in the combination group than in the calcitriol-alone group. However, both mean change and percentage change in the serum FGF23 levels during the 8-week period were not significantly different between the two groups. Serum calcium level was increased significantly only in the combination treatment group. There was no significant difference in percentage change of serum calcium levels between the two groups. In addition, changes in serum levels of phosphate, 25(OH)D, or PTH were not significantly different between the two groups. In correlation analysis, changes in serum FGF23 levels were positively correlated with changes in serum calcium and phosphate levels, but not with changes in 25(OH)D or PTH levels. No serious adverse events were observed, however, there was one case of mild gastrointestinal discomfort. CONCLUSION This study revealed that additional calcium carbonate treatment significantly increased serum FGF23 levels in patients treated with calcitriol, with their synergistic effect in promoting intestinal calcium absorption. This suggests that serum FGF23 levels should be monitored regularly, especially in those who use combination of vitamin D and calcium carbonate from the early stages of CKD.
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Affiliation(s)
- Nayoung Han
- Research Institute of Pharmaceutical Sciences, College of Pharmacy, Seoul National University, Seoul
| | - Su Hyun Hong
- Research Institute of Pharmaceutical Sciences, College of Pharmacy, Seoul National University, Seoul.,Pharmaceutical Standardization Division, Drug Evaluation Department, National Institute of Food and Drug Safety Evaluation, Ministry of Food and Drug Safety, Chungcheongbuk-do
| | - Yon Su Kim
- Division of Nephrology, Department of Internal Medicine, Seoul National University Hospital, Seoul
| | - Dong Ki Kim
- Division of Nephrology, Department of Internal Medicine, Seoul National University Hospital, Seoul
| | - In-Wha Kim
- Research Institute of Pharmaceutical Sciences, College of Pharmacy, Seoul National University, Seoul
| | - Eunhee Ji
- College of Pharmacy, Gachon University, Incheon, Republic of Korea
| | - Jung Mi Oh
- Research Institute of Pharmaceutical Sciences, College of Pharmacy, Seoul National University, Seoul
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8
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Friedl C, Zitt E. Vitamin D prohormone in the treatment of secondary hyperparathyroidism in patients with chronic kidney disease. Int J Nephrol Renovasc Dis 2017; 10:109-122. [PMID: 28546765 PMCID: PMC5436758 DOI: 10.2147/ijnrd.s97637] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Secondary hyperparathyroidism (sHPT) represents the adaptive and very often, finally, maladaptive response of the organism to control the disturbed homeostasis of calcium, phosphorus, and vitamin D metabolism caused by declining renal function in chronic kidney disease (CKD). sHPT leads to cardiovascular and extravascular calcifications and is directly linked to an increased risk of cardiovascular morbidity and mortality as well as excess all-cause mortality. Vitamin D plays an important role in the development of sHPT. CKD patients are characterized by a high prevalence of hypovitaminosis D. Supplementation with both vitamin D prohormones cholecalciferol and ergocalciferol enables the achievement and maintenance of a normal vitamin D status when given in adequate doses over an appropriate treatment period. In patients with earlier stages of CKD, sHPT is influenced by and can be successfully treated with vitamin D prohormone supplementation, whereas in patients with very late stages of CKD and those requiring dialysis, treatment with prohormones seems to be of limited efficacy. This review gives an overview of the pathogenesis of sHPT, summarizes vitamin D metabolism, and discusses the existing literature regarding the role of vitamin D prohormone in the treatment of sHPT in patients with CKD.
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Affiliation(s)
- Claudia Friedl
- Department of Internal Medicine, Clinical Division of Nephrology, Medical University of Graz, Graz
| | - Emanuel Zitt
- Department of Nephrology and Dialysis, Feldkirch Academic Teaching Hospital, Feldkirch, Austria
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9
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Brown RB, Haq A, Stanford CF, Razzaque MS. Vitamin D, phosphate, and vasculotoxicity. Can J Physiol Pharmacol 2015; 93:1077-82. [DOI: 10.1139/cjpp-2015-0083] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Vascular calcification is a complex process that results in the ectopic deposition of calcium-phosphate hydroxyapatite. Medial and intimal vascular calcification is frequently present in patients with diabetes mellitus and chronic kidney disease (CKD), and markedly increases the morbidity and mortality of these patients. Increased serum levels of calcium and phosphate, along with the use of active vitamin D metabolites, are commonly implicated in the evolvement of vascular wall mineralization in CKD patients. Because CKD patients have lower serum levels of vitamin D, they are routinely prescribed vitamin D supplements that exert a dualistic role that is both healthful and harmful in these patients, perhaps protecting bone health, but at the expense of promoting vascular pathology. This review briefly explains how reducing the phosphate burden in CKD patients could minimize vitamin-D-associated vascular wall calcification.
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Affiliation(s)
- Ronald B. Brown
- College of Human Ecology, Kansas State University, Manhattan, KS 66506, USA
| | - Afrozul Haq
- Division of Research & Development, VPS Healthcare, Abu Dhabi, UAE
| | | | - Mohammed S. Razzaque
- Division of Research & Development, VPS Healthcare, Abu Dhabi, UAE
- Department of Applied Oral Sciences, Forsyth Institute, 245 First Street, Cambridge, MA 02142, USA
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10
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Nigwekar SU, Tamez H, Thadhani RI. Vitamin D and chronic kidney disease-mineral bone disease (CKD-MBD). BONEKEY REPORTS 2014; 3:498. [PMID: 24605215 DOI: 10.1038/bonekey.2013.232] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/26/2013] [Accepted: 09/04/2013] [Indexed: 02/07/2023]
Abstract
Chronic kidney disease (CKD) is a modern day epidemic and has significant morbidity and mortality implications. Mineral and bone disorders are common in CKD and are now collectively referred to as CKD- mineral and bone disorder (MBD). These abnormalities begin to appear even in early stages of CKD and contribute to the pathogenesis of renal osteodystrophy. Alteration in vitamin D metabolism is one of the key features of CKD-MBD that has major clinical and research implications. This review focuses on biology, epidemiology and management aspects of these alterations in vitamin D metabolism as they relate to skeletal aspects of CKD-MBD in adult humans.
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Affiliation(s)
- Sagar U Nigwekar
- Division of Nephrology, Massachusetts General Hospital , Boston, MA, USA
| | - Hector Tamez
- Division of Cardiology, Beth Israel Deaconess Medical Center , Boston, MA, USA
| | - Ravi I Thadhani
- Division of Nephrology, Massachusetts General Hospital , Boston, MA, USA
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11
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Nigwekar SU, Bhan I, Thadhani R. Ergocalciferol and Cholecalciferol in CKD. Am J Kidney Dis 2012; 60:139-56. [DOI: 10.1053/j.ajkd.2011.12.035] [Citation(s) in RCA: 82] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2011] [Accepted: 12/27/2011] [Indexed: 12/14/2022]
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12
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D'Amour P, Rousseau L, Hornyak S, Yang Z, Cantor T. Influence of Secondary Hyperparathyroidism Induced by Low Dietary Calcium, Vitamin D Deficiency, and Renal Failure on Circulating Rat PTH Molecular Forms. Int J Endocrinol 2011; 2011:469783. [PMID: 21747853 PMCID: PMC3124668 DOI: 10.1155/2011/469783] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/26/2011] [Accepted: 04/14/2011] [Indexed: 11/24/2022] Open
Abstract
Rats(r) with secondary hyperparathyroidism were studied to define the relationship between vitamin D metabolites and rPTH levels measured by 3 different rat ELISAs. Controls and renal failure (RF) rats were on a normal diet, while 2 groups on a low-calcium (-Ca) or a vitamin D-deficient (-D) diet. RF was induced surgically. Mild RF rats had normal calcium and 25(OH)D but reduced 1,25(OH)(2)D levels (P < .001) with a 2.5-fold increased in rPTH (P < .001). Severe RF rats and those on a -Ca or -D diet had reduced calcium (P < .01) and 25(OH)D levels (P < .05), with rPTH increased by 2 (-Ca diet; P < .05), 4 (-D diet; P < .001), and 20-folds (RF; P < .001) while 1,25(OH)(2)D was high (-Ca diet: P < .001) or low (-D diet, RF: P < .001). 25(OH)D and 1,25(OH)(2)D were positively and negatively related on the -Ca and -D diets, respectively. rPTH molecular forms behaved as expected in RF and on -Ca diet, but not on -D diet with more C-rPTH fragments when less were expected. This may be related to the short-time course of this study compared to prior studies.
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Affiliation(s)
- Pierre D'Amour
- Centre de Recherche, Centre Hospitalier de l'Université de Montréal (CRCHUM), Hôpital Saint-Luc Département de Médecine, Université de Montréal, Montréal, QC, Canada H2X 1P1
- *Pierre D'Amour:
| | - Louise Rousseau
- Centre de Recherche, Centre Hospitalier de l'Université de Montréal (CRCHUM), Hôpital Saint-Luc Département de Médecine, Université de Montréal, Montréal, QC, Canada H2X 1P1
| | | | - Zan Yang
- Scantibodies Laboratory Inc., Santee, CA 92071, USA
| | - Tom Cantor
- Scantibodies Laboratory Inc., Santee, CA 92071, USA
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Abstract
Although protein-energy malnutrition occurs commonly in patients with end-stage renal disease undergoing maintenance dialysis treatment, it is not the only form of malnutrition that may exist in these individuals. They may also suffer from deficiencies of micronutrients, particularly trace elements and vitamins. More commonly occurring vitamin deficiencies in maintenance dialysis patients include those for vitamin C (ascorbate), folate, vitamin B6 (pyridoxine), and 1,25-dihydroxycholecalciferol (calcitriol). Among trace elements, deficiencies may occur more commonly for iron, zinc, and possibly selenium, whereas toxicities are more common with aluminum and possibly copper. Evidence suggests that there is an abnormally high prevalence of antioxidant deficiency in maintenance dialysis patients, especially because a low intake of protein and energy may be associated with inadequate ingestion of antioxidant vitamins (ie, vitamins E and C and carotenoids). Thus, some micronutrient deficiencies in maintenance dialysis patients may contribute to the development of atherosclerotic cardiovascular disease. Dietary requirements for vitamins and trace elements in maintenance dialysis patients are reviewed and the recommended daily intakes are discussed.
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Affiliation(s)
- Kamyar Kalantar-Zadeh
- Division of Nephrology and Hypertension, Harbor-UCLA Medical Center, and David Geffen School of Medicine, University of California Los Angeles, Torrance, CA 90509-2910, USA.
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14
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Pahl MV, Barbari A, Vaziri ND, Hollander D, Yazdani M, Tran J, Kan R. Intestinal absorption of linoleic acid in experimental renal failure. Br J Nutr 1991; 66:467-77. [PMID: 1772871 DOI: 10.1079/bjn19910048] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Linoleic acid (LA) transport in rats with experimental short-term and long-term renal failure (RF) was compared with that of sham-operated normal animals on liberal food intake and pair-fed animals. The perfusions in vivo and incubations in vitro were conducted using a micellar solution containing a wide range of LA concentrations. Both absorption in vivo and uptake in vitro of LA were significantly reduced in animals with short-term RF. Lipid extraction and separation by thin-layer chromatography revealed a marked LA trapping as trilinolein (TL) in the perfused intestinal tissue in the short-term RF group. The esterification process, as defined by the rate of LA incorporation into TL, was moderately reduced in short-term RF animals. The thickness of the unstirred water layer showed no significant difference among the groups studied. In contrast, animals with long-term RF exhibited normal absorption of LA in vivo at all concentrations tested. In conclusion, LA absorption is reduced in short-term RF and restored in long-term RF. Several steps including LA transport into and TL transport out of the enterocyte and the esterification process were impaired in short-term RF. These changes are not due to alteration in the unstirred water layer, anorexia, weight loss or a rapid effect of uraemic chemical environment or circulatory factors.
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Affiliation(s)
- M V Pahl
- Department of Medicine, University of California, Irvine 92668
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15
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Pahl MV, Barbari A, Vaziri ND, Hollander D, Sanchez M, Oveisi F, Patel N. Intestinal absorption of arachidonic acid in experimental azotemia. Life Sci 1990; 46:1649-56. [PMID: 2113152 DOI: 10.1016/0024-3205(90)90379-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
The effect of renal failure (RF) on intestinal absorption of dietary fatty acids is not known. We studied the intestinal absorption of arachidonic acid (AA) in rats with experimental short-term (2 weeks post-subtotal nephrectomy) and long-term (5-6 weeks post-subtotal nephrectomy) RF. The results were compared with those obtained in sham-operated animals on liberal food intake (NL) and in those pair-fed (PF) with the respective RF groups. In vivo perfusion and in vitro incubation experiments were performed at a wide range of AA concentrations. The rates of AA transport determined both in vivo and in vitro were significantly lower in the short-term RF group than those found in the NL controls and the PF animals who showed comparable values. In contrast animals with long-term RF exhibited an increased rate of AA transport as compared with the respective controls. The observed changes in the transport rates appeared to parallel directional changes in mucosal mass which was reduced in animals with short-term RF and restored in those with long-term RF.
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Affiliation(s)
- M V Pahl
- Department of Medicine, University of California, Irvine 92717
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16
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Inagaki O, Syono T, Nagasaka H, Fujita Y, Inoue S, Mori H. Effect of 1,25-dihydroxyvitamin D3 on intestinal glucose absorption in uremic rats. Ren Fail 1989; 11:17-21. [PMID: 2772282 DOI: 10.3109/08860228909066941] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
The effect of 1,25-dihydroxyvitamin D3 (1,25-D) on the absorption of glucose in the small intestine was studied in five-sixths nephrectomized uremic rats and sham-operated rats. Four weeks after the nephrectomy, the uremic animals were divided into two groups: One group was given 1,25-D (300 pmol/kg body weight/day, three times per week) intraperitoneally, and the other was left untreated. One week after the 1,25-D treatment, an in vivo glucose absorption test was performed at 00.00 h in consideration of the circadian rhythm of glucose absorption. In untreated uremic rats, the glucose absorption rate was lower than in sham-operated rats. In 1,25-D treated uremic rats, the glucose absorption rate was higher than in untreated uremic rats and not lower than in sham-operated rats. These results suggest that the absorption rate of glucose of the small intestine is reduced in uremic rats and that it is recovered on treatment with 1,25-D.
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Affiliation(s)
- O Inagaki
- Dialysis Unit, Hyogo College of Medicine, Nishinomiya, Japan
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Barbari A, Vaziri ND, Benavides I, Chen YT, Said H, Pahl MV. Intestinal transport of pyridoxine in experimental renal failure. Life Sci 1989; 45:663-9. [PMID: 2770420 DOI: 10.1016/0024-3205(89)90053-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Renal failure (RF) has been shown to alter intestinal transport of a number of nutrients. We studied jejunal absorption of pyridoxine (B6) in rats rendered azotemic by subtotal nephrectomy (RF group) and compared the results with those obtained in normal rats subjected to sham operation (controls) and animals pair-fed (PF) with their RF counterparts. In vivo recirculating perfusion and in vitro everted sac techniques were employed. The in vitro experiments were repeated using sera from uremic and normal individuals to assess the possible effect of uremic chemical environment. The results showed significant reduction in B6 absorption in vivo in the RF group as compared to the control and PF groups. Paradoxically, the rate of in vitro B6 absorption determined for a wide range of concentrations was increased in the RF and PF groups as compared to the control group. The observed increase in B6 absorption in vitro suggests enhanced permeability in the RF and PF groups due probably to reduced nutrient intake which was common to both groups. The disparity between the in vivo and in vitro results is indicative of some inhibitory factor(s) present in the RF animals. Sacs containing uremic serum showed significantly suppressed B6 absorption in vitro as compared to those containing normal serum. These observations suggest that the uremic chemical environment may be, in part, responsible for the observed impairment of B6 transport in RF animals despite in vitro evidence of hyperpermeability.
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Affiliation(s)
- A Barbari
- Department of Medicine, University of California, Irvine 92717
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