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Lautrou M, Narcy A, Dourmad JY, Pomar C, Schmidely P, Létourneau Montminy MP. Dietary Phosphorus and Calcium Utilization in Growing Pigs: Requirements and Improvements. Front Vet Sci 2021; 8:734365. [PMID: 34901241 PMCID: PMC8654138 DOI: 10.3389/fvets.2021.734365] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2021] [Accepted: 10/04/2021] [Indexed: 11/13/2022] Open
Abstract
The sustainability of animal production relies on the judicious use of phosphorus (P). Phosphate, the mined source of agricultural phosphorus supplements, is a non-renewable resource, but phosphorus is essential for animal growth, health, and well-being. P must be provided by efficient and sustainable means that minimize the phosphorus footprint of livestock production by developing precise assessment of the bioavailability of dietary P using robust models. About 60% of the phosphorus in an animal's body occurs in bone at a fixed ratio with calcium (Ca) and the rest is found in muscle. The P and Ca requirements must be estimated together; they cannot be dissociated. While precise assessment of P and Ca requirements is important for animal well-being, it can also help to mitigate the environmental effects of pig farming. These strategies refer to multicriteria approaches of modeling, efficient use of the new generations of phytase, depletion and repletion strategies to prime the animal to be more efficient, and finally combining these strategies into a precision feeding model that provides daily tailored diets for individuals. The industry will need to use strategies such as these to ensure a sustainable plant–animal–soil system and an efficient P cycle.
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Affiliation(s)
- Marion Lautrou
- Département des sciences animales, Université Laval, Quebec, QC, Canada.,UMR Modélisation Systémique Appliquée aux Ruminants, INRA, AgroParisTech, Université Paris-Saclay, Paris, France
| | - Agnès Narcy
- UMR Biologie des oiseaux et aviculture, INRA, Nouzilly, France
| | | | - Candido Pomar
- Agriculture et Agroalimentaire Canada, Sherbrooke, QC, Canada
| | - Philippe Schmidely
- UMR Modélisation Systémique Appliquée aux Ruminants, INRA, AgroParisTech, Université Paris-Saclay, Paris, France
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Li A, Yi B, Han H, Yang S, Hu Z, Zheng L, Wang J, Liao Q, Zhang H. Vitamin D-VDR (vitamin D receptor) regulates defective autophagy in renal tubular epithelial cell in streptozotocin-induced diabetic mice via the AMPK pathway. Autophagy 2021; 18:877-890. [PMID: 34432556 PMCID: PMC9037529 DOI: 10.1080/15548627.2021.1962681] [Citation(s) in RCA: 40] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Diabetic nephropathy (DN) has become a major cause of end-stage renal disease, and autophagy disorder is implicated in the pathogenesis of DN. Our previous studies found that vitamin D (VD) and VDR (vitamin D receptor) played a renoprotective role by inhibiting inflammation and fibrosis. However, whether VD-VDR regulates autophagy disorders in DN remains unclear. In this study, we established a streptozotocin (STZ)-induced diabetic model in vdr knockout (vdr-KO) mice and VDR specifically overexpressed in renal proximal tubular epithelial cells (Vdr-OE) mice. Our results showed that paricalcitol (an activated vitamin D analog) or Vdr-OE could alleviate STZ-induced ALB (albumin) excretion, renal tubule injury and inflammation, while these were worsened in vdr-KO mice. Defective autophagy was observed in the kidneys of STZ mice, which was more pronounced in vdr-KO mice and could be partially restored by paricalcitol or Vdr-OE. In high glucose-induced HK-2 cells, defective autophagy and decreased PRKAA1/AMPK phosphorylation was observed, which could be partially restored by paricalcitol in a VDR-dependent manner. AMPK inhibitor abolished paricalcitol-induced autophagy activation, and AMPK activator restored the defective autophagy in high glucose-induced HK-2 cells. Furthermore, paricalcitol-mediated AMPK activation was abrogated by CAMKK2/CaMKKβ inhibition, but not by STK11/LKB1 knockout. Meanwhile, paricalcitol rescued the decreased Ca2+ concentration induced by high glucose. In conclusion, VD-VDR can restore defective autophagy in the kidney of STZ-induced diabetic mice, which could be attributed to the activation of the Ca2+-CAMKK2-AMPK pathway in renal tubular epithelial cells. Abbreviations: ACTB/β-actin: actin beta;AGE: advanced glycation end-products;AMPK: AMP-activated protein kinase;CAMKK2/CaMKKβ: calcium-calmodulin dependent protein kinase kinase 2;CQ: chloroquine;DN: diabetic nephropathy;HG: high levels of glucose;KO: knockout;LG: low levels of glucose;MAP1LC3/LC3: microtubule associated protein 1 light chain 3;NOD2: nucleotide binding oligomerization domain containing 2;OE: overexpression;PAS: periodic acid Schiff; Pari: paricalcitol;PTECs: proximal renal tubule epithelial cells;RT: room temperature;SQSTM1/p62: sequestosome 1;STK11/LKB1: serine/threonine kinase 11;STZ: streptozotocin;TEM: transmission electron microscopy;VD: vitamin D;VDR: vitamin D receptor;WT: wild-type
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Affiliation(s)
- Aimei Li
- Department of Nephrology, The Third Xiangya Hospital, Central South University, Changsha, Hunan, China
| | - Bin Yi
- Department of Nephrology, The Third Xiangya Hospital, Central South University, Changsha, Hunan, China
| | - Hailong Han
- Centre For Medical Genetics And Hunan Key Laboratory of Medical Genetics, School Of Life Sciences, Central South University, Changsha, Hunan, China.,Department of Neuroscience, Postdoctoral Station For Basic Medicine, Hengyang School of Medicine, University of South China, Hengyang, Hunan, China
| | - Shikun Yang
- Department of Nephrology, The Third Xiangya Hospital, Central South University, Changsha, Hunan, China
| | - Zhaoxin Hu
- Department of Nephrology, The Third Xiangya Hospital, Central South University, Changsha, Hunan, China
| | - Li Zheng
- Department of Nephrology, The Third Xiangya Hospital, Central South University, Changsha, Hunan, China
| | - Jianwen Wang
- Department of Nephrology, The Third Xiangya Hospital, Central South University, Changsha, Hunan, China
| | - Qin Liao
- Department of Anesthesiology, The Third Xiangya Hospital, Central South University, Changsha, Hunan, China
| | - Hao Zhang
- Department of Nephrology, The Third Xiangya Hospital, Central South University, Changsha, Hunan, China
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Wongdee K, Rodrat M, Teerapornpuntakit J, Krishnamra N, Charoenphandhu N. Factors inhibiting intestinal calcium absorption: hormones and luminal factors that prevent excessive calcium uptake. J Physiol Sci 2019; 69:683-696. [PMID: 31222614 PMCID: PMC10717634 DOI: 10.1007/s12576-019-00688-3] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2019] [Accepted: 06/09/2019] [Indexed: 12/11/2022]
Abstract
Besides the two canonical calciotropic hormones, namely parathyroid hormone and 1,25-dihydroxyvitamin D [1,25(OH)2D3], there are several other endocrine and paracrine factors, such as prolactin, estrogen, and insulin-like growth factor that have been known to directly stimulate intestinal calcium absorption. Generally, to maintain an optimal plasma calcium level, these positive regulators enhance calcium absorption, which is indirectly counterbalanced by a long-loop negative feedback mechanism, i.e., through calcium-sensing receptor in the parathyroid chief cells. However, several lines of recent evidence have revealed the presence of calcium absorption inhibitors present in the intestinal lumen and extracellular fluid in close vicinity to enterocytes, which could also directly compromise calcium absorption. For example, luminal iron, circulating fibroblast growth factor (FGF)-23, and stanniocalcin can decrease calcium absorption, thereby preventing excessive calcium uptake under certain conditions. Interestingly, the intestinal epithelial cells themselves could lower their rate of calcium uptake after exposure to high luminal calcium concentration, suggesting a presence of an ultra-short negative feedback loop independent of systemic hormones. The existence of neural regulation is also plausible but this requires more supporting evidence. In the present review, we elaborate on the physiological significance of these negative feedback regulators of calcium absorption, and provide evidence to show how our body can efficiently restrict a flood of calcium influx in order to maintain calcium homeostasis.
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Affiliation(s)
- Kannikar Wongdee
- Faculty of Allied Health Sciences, Burapha University, Chonburi, Thailand
- Center of Calcium and Bone Research (COCAB), Faculty of Science, Mahidol University, Bangkok, Thailand
| | - Mayuree Rodrat
- Center of Calcium and Bone Research (COCAB), Faculty of Science, Mahidol University, Bangkok, Thailand
- Department of Physiology, Faculty of Science, Mahidol University, Rama VI Road, Bangkok, 10400, Thailand
| | - Jarinthorn Teerapornpuntakit
- Center of Calcium and Bone Research (COCAB), Faculty of Science, Mahidol University, Bangkok, Thailand
- Department of Physiology, Faculty of Medical Science, Naresuan University, Phitsanulok, Thailand
| | - Nateetip Krishnamra
- Center of Calcium and Bone Research (COCAB), Faculty of Science, Mahidol University, Bangkok, Thailand
- Department of Physiology, Faculty of Science, Mahidol University, Rama VI Road, Bangkok, 10400, Thailand
| | - Narattaphol Charoenphandhu
- Center of Calcium and Bone Research (COCAB), Faculty of Science, Mahidol University, Bangkok, Thailand.
- Department of Physiology, Faculty of Science, Mahidol University, Rama VI Road, Bangkok, 10400, Thailand.
- Institute of Molecular Biosciences, Mahidol University, Nakhon Pathom, Thailand.
- The Academy of Science, The Royal Society of Thailand, Dusit, Bangkok, Thailand.
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Transcriptome Analysis of Adipose Tissue Indicates That the cAMP Signaling Pathway Affects the Feed Efficiency of Pigs. Genes (Basel) 2018; 9:genes9070336. [PMID: 29973485 PMCID: PMC6070815 DOI: 10.3390/genes9070336] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2018] [Revised: 06/15/2018] [Accepted: 06/28/2018] [Indexed: 12/25/2022] Open
Abstract
Feed efficiency (FE) is one of the main factors that determine the production costs in the pig industry. In this study, RNA Sequencing (RNA-seq) was applied to identify genes and long intergenic non-coding RNAs (lincRNAs) that are differentially expressed (DE) in the adipose tissues of Yorkshire pigs with extremely high and low FE. In total, 147 annotated genes and 18 lincRNAs were identified as DE between high- and low-FE pigs. Seventeen DE lincRNAs were significantly correlated with 112 DE annotated genes at the transcriptional level. Gene ontology (GO) analysis revealed that DE genes were significantly associated with cyclic adenosine monophosphate (cAMP) metabolic process and Ca2+ binding. cAMP, a second messenger has an important role in lipolysis, and its expression is influenced by Ca2+ levels. In high-FE pigs, nine DE genes with Ca2+ binding function, were down-regulated, whereas S100G, which encodes calbindin D9K that serve as a Ca2+ bumper, was up-regulated. Furthermore, ATP2B2, ATP1A4, and VIPR2, which participate in the cAMP signaling pathway, were down-regulated in the upstream of lipolysis pathways. In high-FE pigs, the key genes involved in the lipid biosynthetic process (ELOVL7 and B4GALT6), fatty acid oxidation (ABCD2 and NR4A3), and lipid homeostasis (C1QTNF3 and ABCB4) were down-regulated. These results suggested that cAMP was involved in the regulation on FE of pigs by affecting lipid metabolism in adipose tissues.
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Lertsuwan K, Wongdee K, Teerapornpuntakit J, Charoenphandhu N. Intestinal calcium transport and its regulation in thalassemia: interaction between calcium and iron metabolism. J Physiol Sci 2018; 68:221-232. [PMID: 29484538 PMCID: PMC10717198 DOI: 10.1007/s12576-018-0600-1] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2017] [Accepted: 02/17/2018] [Indexed: 01/19/2023]
Abstract
Osteoporosis and derangement of calcium homeostasis are common complications of thalassemia. Despite being an important process for bone and calcium metabolism, little is known about intestinal calcium transport in thalassemia. Recent reports of decreases in both intestinal calcium transport and bone mineral density in thalassemic patients and animal models suggested that defective calcium absorption might be a cause of thalassemic bone disorder. Herein, the possible mechanisms associated with intestinal calcium malabsorption in thalassemia are discussed. This includes alterations in the calcium transporters and hormonal controls of the transcellular and paracellular intestinal transport systems in thalassemia. In addition, the effects of iron overload on intestinal calcium absorption, and the reciprocal interaction between iron and calcium transport in thalassemia are elaborated. Understanding the mechanisms underlining calcium malabsorption in thalassemia would lead to development of therapeutic agents and mineral supplements that restore calcium absorption as well as prevent osteoporosis in thalassemic patients.
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Affiliation(s)
- Kornkamon Lertsuwan
- Department of Biochemistry, Faculty of Science, Mahidol University, Rama VI Road, Bangkok, 10400, Thailand
- Center of Calcium and Bone Research (COCAB), Faculty of Science, Mahidol University, Rama VI Road, Bangkok, 10400, Thailand
| | - Kannikar Wongdee
- Center of Calcium and Bone Research (COCAB), Faculty of Science, Mahidol University, Rama VI Road, Bangkok, 10400, Thailand
- Office of Academic Management, Faculty of Allied Health Sciences, Burapha University, Chonburi, Thailand
| | - Jarinthorn Teerapornpuntakit
- Center of Calcium and Bone Research (COCAB), Faculty of Science, Mahidol University, Rama VI Road, Bangkok, 10400, Thailand
- Department of Physiology, Faculty of Medical Science, Naresuan University, Phitsanulok, Thailand
| | - Narattaphol Charoenphandhu
- Center of Calcium and Bone Research (COCAB), Faculty of Science, Mahidol University, Rama VI Road, Bangkok, 10400, Thailand.
- Department of Physiology, Faculty of Science, Mahidol University, Rama VI Road, Bangkok, 10400, Thailand.
- Institute of Molecular Biosciences, Mahidol University, Nakhon Pathom, Thailand.
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Prolonged exposure to 1,25(OH) 2D 3 and high ionized calcium induces FGF-23 production in intestinal epithelium-like Caco-2 monolayer: A local negative feedback for preventing excessive calcium transport. Arch Biochem Biophys 2018; 640:10-16. [PMID: 29317227 DOI: 10.1016/j.abb.2017.12.022] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2017] [Revised: 11/19/2017] [Accepted: 12/07/2017] [Indexed: 12/13/2022]
Abstract
Overdose of oral calcium supplement and excessive intestinal calcium absorption can contribute pathophysiological conditions, e.g., nephrolithiasis, vascular calcification, dementia, and cardiovascular accident. Since our previous investigation has indicated that fibroblast growth factor (FGF)-23 could abolish the 1,25-dihydroxyvitamin D3 [1,25(OH)2D3]-enhanced calcium absorption, we further hypothesized that FGF-23 produced locally in the enterocytes might be part of a local negative feedback loop to regulate calcium absorption. Herein, 1,25(OH)2D3 was found to enhance the transcellular calcium transport across the epithelium-like Caco-2 monolayer, and this stimulatory effect was diminished by preceding prolonged exposure to high-dose 1,25(OH)2D3 or high concentration of apical ionized calcium. Pretreatment with a neutralizing antibody for FGF-23 prevented this negative feedback regulation of calcium hyperabsorption induced by 1,25(OH)2D3. FGF-23 exposure completely abolished the 1,25(OH)2D3-enhanced calcium transport. Western blot analysis revealed that FGF-23 expression was upregulated in a dose-dependent manner by 1,25(OH)2D3 or apical calcium exposure. Finally, calcium-sensing receptor (CaSR) inhibitors were found to prevent the apical calcium-induced suppression of calcium transport. In conclusion, prolonged exposure to high apical calcium and calcium hyperabsorption were sensed by CaSR, which, in turn, increased FGF-23 expression to suppress calcium transport. This local negative feedback loop can help prevent unnecessary calcium uptake and its detrimental consequences.
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Christakos S, Veldurthy V, Patel N, Wei R. Intestinal Regulation of Calcium: Vitamin D and Bone Physiology. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2017; 1033:3-12. [PMID: 29101648 DOI: 10.1007/978-3-319-66653-2_1] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The principal function of vitamin D in the maintenance of calcium homeostasis is to increase intestinal calcium absorption. This conclusion was made from studies in vitamin D receptor (VDR) null mice which showed that rickets and osteomalacia were prevented when VDR null mice were fed a rescue diet that included high calcium, indicating that the skeletal abnormalities of the VDR null mice are primarily the result of impaired intestinal calcium absorption. Although vitamin D is critical for controlling intestinal calcium absorption, the mechanisms involved have remained incomplete. This chapter reviews studies, including studies in genetically modified mice, that have provided new insight and have challenged the traditional model of VDR-mediated calcium absorption.
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Affiliation(s)
- Sylvia Christakos
- Department of Microbiology, Biochemistry and Molecular Genetics, Rutgers the State University of New Jersey, New Jersey Medical School, 185 South Orange Ave, Newark, NJ, 07103, USA.
| | - Vaishali Veldurthy
- Department of Microbiology, Biochemistry and Molecular Genetics, Rutgers the State University of New Jersey, New Jersey Medical School, 185 South Orange Ave, Newark, NJ, 07103, USA
| | - Nishant Patel
- Department of Microbiology, Biochemistry and Molecular Genetics, Rutgers the State University of New Jersey, New Jersey Medical School, 185 South Orange Ave, Newark, NJ, 07103, USA
| | - Ran Wei
- Department of Microbiology, Biochemistry and Molecular Genetics, Rutgers the State University of New Jersey, New Jersey Medical School, 185 South Orange Ave, Newark, NJ, 07103, USA
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Abstract
For humans and rodents, duodenum is a very important site of calcium absorption since it is exposed to ionized calcium released from dietary complexes by gastric acid. Calcium traverses the duodenal epithelium via both transcellular and paracellular pathways in a vitamin D-dependent manner. After binding to the nuclear vitamin D receptor, 1,25-dihydroxyvitamin D3 [1,25(OH)2D3] upregulates the expression of several calcium transporter genes, e.g., TRPV5/6, calbindin-D9k, plasma membrane Ca(2+)-ATPase1b, and NCX1, thereby enhancing the transcellular calcium transport. This action has been reported to be under the regulation of parathyroid-kidney-intestinal and bone-kidney-intestinal axes, in which the plasma calcium and fibroblast growth factor-23 act as negative feedback regulators, respectively. 1,25(OH)2D3 also modulates the expression of tight junction-related genes and convective water flow, presumably to increase the paracellular calcium permeability and solvent drag-induced calcium transport. However, vitamin D-independent calcium absorption does exist and plays an important role in calcium homeostasis under certain conditions, particularly in neonatal period, pregnancy, and lactation as well as in naturally vitamin D-impoverished subterranean mammals.
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Haxhiu D, Hoby S, Wenker C, Boos A, Kowalewski MP, Lewis F, Liesegang A. Influence of feeding and UVB exposition on the absorption mechanisms of calcium in the gastrointestinal tract of veiled chameleons (Chamaeleo calyptratus). J Anim Physiol Anim Nutr (Berl) 2014; 98:1021-30. [PMID: 24848550 PMCID: PMC4280901 DOI: 10.1111/jpn.12206] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2013] [Accepted: 05/01/2014] [Indexed: 01/02/2023]
Abstract
The purpose of this study was to investigate the influence of feeding and UVB exposition on the occurrence and distribution patterns of vitamin D receptors (VDR) and calbindin D28k (Cb-D28k) in the gastrointestinal tract of veiled chameleons. Thus, 56 veiled chameleon hatchlings were divided into six treatment groups: UV (with UVB exposure); No (no supplements, no UVB exposure); CaAUV (with calcium (Ca), vitamin A supplementation, UVB exposure); CaA (with Ca, vitamin A supplementation); CaADUV (with Ca, vitamin A, vitamin D supplementation, UVB exposure); and CaAD (with Ca, vitamin A, vitamin D supplementation). Animals were reared under the suspected conditions for 6 months on locust-based diets. Tissue samples of stomach, duodenum, ileum and colon were taken, and semi-quantitative immunohistochemical methods (IHC) were performed to detect Cb-D28k and VDR. VDR immunoreactions were higher in the luminal epithelium of the duodenum than in that of the ileum. VDR immunoreactions in the luminal epithelium were higher at the base of the villi of the duodenum as compared to the tip. Cb-D28k immunoreactions were mainly observed in the luminal epithelium of the duodenum. The two groups treated with all dietary supplements (CaADUV, CaAD) exhibited a higher Cb-D28k immunoreaction as those with no supplements and UVB exposure only. No immunoreaction for both proteins could be detected in the stomach. This study suggests that the duodenum plays an important role in the active transcellular absorption of Ca in veiled chameleons as shown by the immunohistochemical detection of VDR and Cb-D28k. Expression of Cb-D28k, in particular, appears to be regulated by dietary supplementation of vitamin D and vitamin A. VDRs, however, tended to be upregulated when animals were not supplemented with Ca, vitamin D and vitamin A. This may be due to the decreased Ca concentrations which caused vitamin D activation in the skin without any supplementation, but UVB exposure.
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Affiliation(s)
- D Haxhiu
- Vetsuisse Faculty, Institute of Animal Nutrition, University of Zurich, Zurich, Switzerland
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Hwang I, Yang H, Kang HS, Ahn C, Hong EJ, An BS, Jeung EB. Alteration of tight junction gene expression by calcium- and vitamin D-deficient diet in the duodenum of calbindin-null mice. Int J Mol Sci 2013; 14:22997-3010. [PMID: 24264043 PMCID: PMC3856102 DOI: 10.3390/ijms141122997] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2013] [Revised: 11/01/2013] [Accepted: 11/06/2013] [Indexed: 01/01/2023] Open
Abstract
Calcium absorption is regulated by both active (transcellular) and passive (paracellular) pathways. Although each pathway has been studied, correlations between the two pathways have not been well elucidated. In previous investigations, the critical transcellular proteins, calbindin-D9k (CaBP-9k) and -D28k (CaBP-28k), were shown to affect other transcellular pathways by buffering intracellular calcium concentrations. The rate of paracellular calcium transport in the duodenum is generally determined by the expression of tight junction genes. In the present study, the effect of dietary calcium and/or vitamin D supplementation on the expression of tight junction genes (occludin, ZO-1 and claudin 2, 10b, 12 and 15) in the duodenum of CaBP-9k- and/or -28k-deficient mice was examined. With a normal diet, the expression of most tight junction genes in the duodenum was significantly increased in CaBP-9k knockout (KO) mice compared to wild-type (WT) animals. With a calcium- and vitamin D-deficient diet, tight junction gene expression was significantly decreased in the duodenum of the CaBP-9k KO mice. These findings suggest that expression of paracellular tight junction genes is regulated by transcellular CaBP proteins, suggesting that active and passive calcium transport pathways may function cooperatively.
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Affiliation(s)
- Inho Hwang
- Laboratory of Veterinary Biochemistry and Molecular Biology, College of Veterinary Medicine, Chungbuk National University, Cheongju, Chungbuk 361-763, Korea; E-Mails: (I.H.); (H.Y.); (H.-S.K.); (C.A.); (E.-J.H.)
| | - Hyun Yang
- Laboratory of Veterinary Biochemistry and Molecular Biology, College of Veterinary Medicine, Chungbuk National University, Cheongju, Chungbuk 361-763, Korea; E-Mails: (I.H.); (H.Y.); (H.-S.K.); (C.A.); (E.-J.H.)
| | - Hong-Seok Kang
- Laboratory of Veterinary Biochemistry and Molecular Biology, College of Veterinary Medicine, Chungbuk National University, Cheongju, Chungbuk 361-763, Korea; E-Mails: (I.H.); (H.Y.); (H.-S.K.); (C.A.); (E.-J.H.)
| | - Changhwan Ahn
- Laboratory of Veterinary Biochemistry and Molecular Biology, College of Veterinary Medicine, Chungbuk National University, Cheongju, Chungbuk 361-763, Korea; E-Mails: (I.H.); (H.Y.); (H.-S.K.); (C.A.); (E.-J.H.)
| | - Eui-Ju Hong
- Laboratory of Veterinary Biochemistry and Molecular Biology, College of Veterinary Medicine, Chungbuk National University, Cheongju, Chungbuk 361-763, Korea; E-Mails: (I.H.); (H.Y.); (H.-S.K.); (C.A.); (E.-J.H.)
| | - Beum-Soo An
- Department of Biomaterials Science, College of National Resources & Life Science, Pusan National University, 1268-50 Samrangjin-ro, Samrangjin-eup, Miryang-si, Gyeongsangnam-do 627-706, Korea; E-Mail:
| | - Eui-Bae Jeung
- Laboratory of Veterinary Biochemistry and Molecular Biology, College of Veterinary Medicine, Chungbuk National University, Cheongju, Chungbuk 361-763, Korea; E-Mails: (I.H.); (H.Y.); (H.-S.K.); (C.A.); (E.-J.H.)
- Author to whom correspondence should be addressed; E-Mail: ; Tel.: +82-43-261-2397; Fax: +82-43-267-3150
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Cui M, Li Q, Johnson R, Fleet JC. Villin promoter-mediated transgenic expression of transient receptor potential cation channel, subfamily V, member 6 (TRPV6) increases intestinal calcium absorption in wild-type and vitamin D receptor knockout mice. J Bone Miner Res 2012; 27:2097-107. [PMID: 22589201 PMCID: PMC3430830 DOI: 10.1002/jbmr.1662] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Transient receptor potential cation channel, subfamily V, member 6 (TRPV6) is an apical membrane calcium (Ca) channel in the small intestine proposed to be essential for vitamin D-regulated intestinal Ca absorption. Recent studies have challenged the proposed role for TRPV6 in Ca absorption. We directly tested intestinal TRPV6 function in Ca and bone metabolism in wild-type (WT) and vitamin D receptor knockout (VDRKO) mice. TRPV6 transgenic mice (TG) were made with intestinal epithelium-specific expression of a 3X Flag-tagged human TRPV6 protein. TG and VDRKO mice were crossed to make TG-VDRKO mice. Ca and bone metabolism was examined in WT, TG, VDRKO, and TG-VDRKO mice. TG mice developed hypercalcemia and soft tissue calcification on a chow diet. In TG mice fed a 0.25% Ca diet, Ca absorption was more than three-fold higher and femur bone mineral density (BMD) was 26% higher than WT. Renal 1α hydroxylase (CYP27B1) mRNA and intestinal expression of the natural mouse TRPV6 gene were reduced to <10% of WT but small intestine calbindin-D(9k) expression was elevated >15 times in TG mice. TG-VDRKO mice had high Ca absorption that prevented the low serum Ca, high renal CYP27B1 mRNA, low BMD, and abnormal bone microarchitecture seen in VDRKO mice. In addition, small intestinal calbindin D(9K) mRNA and protein levels were elevated in TG-VDRKO. Transgenic TRPV6 expression in intestine is sufficient to increase Ca absorption and bone density, even in VDRKO mice. VDR-independent upregulation of intestinal calbindin D(9k) in TG-VDRKO suggests this protein may buffer intracellular Ca during Ca absorption. © 2012 American Society for Bone and Mineral Research.
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Affiliation(s)
- Min Cui
- Department of Nutrition Science, Purdue University, West Lafayette, IN 47907-2059, USA
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Zhou Y, Tzeng WP, Yang W, Zhou Y, Ye Y, Lee HW, Frey TK, Yang J. Identification of a Ca2+-binding domain in the rubella virus nonstructural protease. J Virol 2007; 81:7517-28. [PMID: 17475644 PMCID: PMC1933374 DOI: 10.1128/jvi.00605-07] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
The rubella virus (RUB) nonstructural protein (NS) open reading frame (ORF) encodes a polypeptide precursor that is proteolytically self cleaved into two replicase components involved in viral RNA replication. A putative EF-hand Ca(2+)-binding motif that was conserved across different genotypes of RUB was predicted within the nonstructural protease that cleaves the precursor by using bioinformatics tools. To probe the metal-binding properties of this motif, we used an established grafting approach and engineered the 12-residue Ca(2+)-coordinating loop into a non-Ca(2+)-binding scaffold protein, CD2. The grafted EF-loop bound to Ca(2+) and its trivalent analogs Tb(3+) and La(3+) with K(d)s of 214, 47, and 14 microM, respectively. Mutations (D1210A and D1217A) of two of the potential Ca(2+)-coordinating ligands in the EF-loop led to the elimination of Tb(3+) binding. Inductive coupled plasma mass spectrometry was used to confirm the presence of Ca(2+) ([Ca(2+)]/[protein] = 0.7 +/- 0.2) in an NS protease minimal metal-binding domain, RUBCa, that spans the EF-hand motif. Conformational studies on RUBCa revealed that Ca(2+) binding induced local conformational changes and increased thermal stability (Delta T(m) = 4.1 degrees C). The infectivity of an RUB infectious cDNA clone containing the mutations D1210A/D1217A was decreased by approximately 20-fold in comparison to the wild-type (wt) clone, and these mutations rapidly reverted to the wt sequence. The NS protease containing these mutations was less efficient at precursor cleavage than the wt NS protease at 35 degrees C, and the mutant NS protease was temperature sensitive at 39 degrees C, confirming that the Ca(2+)-binding loop played a structural role in the NS protease and was specifically required for optimal stability under physiological conditions.
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Affiliation(s)
- Yubin Zhou
- Department of Chemistry, Georgia State University, 50 Decatur St., Atlanta, GA 30303, USA
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Schröder B, Breves G. Mechanisms and regulation of calcium absorption from the gastrointestinal tract in pigs and ruminants: comparative aspects with special emphasis on hypocalcemia in dairy cows. Anim Health Res Rev 2007; 7:31-41. [PMID: 17389052 DOI: 10.1017/s1466252307001144] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Adequate blood calcium (Ca) concentrations are a prerequisite to maintain several physiological functions of mammals such as pig and ruminants. Thus, blood Ca levels have to be regulated within very close limits. This is basically ensured through the coordinated effects of the calcitropic hormones parathyroid hormone (PTH) and calcitriol (1,25-dihydroxyvitamin D3). If plasma Ca decreases, one main effect of subsequently secreted PTH is the stimulation of renal reabsorption of Ca from the glomerular filtrate to reduce urinary Ca loss. Another important action of PTH is the induction of the renal enzyme 1[@@@]\rmalpha [@@@]-hydroxylase, which is responsible for the production of calcitriol. In most monogastric species, so far investigated, one of the most important effects of calcitriol is to stimulate active absorption of Ca from the gastrointestinal tract, particularly the upper small intestines, via a vitamin D-receptor-mediated genomic action. Whether this concept can be transferred without any constrictions to ruminants is still under discussion. Marked interspecies differences have to be recognized with respect to ruminant or non-ruminant animals, particularly with respect to individual segments along the gastrointestinal axis and with respect to vitamin D sensitivity of Ca transport mechanisms. This review will elucidate some of the current concepts related to the mechanisms and sites of Ca absorption in pigs and ruminants with special emphasis on dairy cows where Ca homeostasis is occasionally compromised at the time of parturition.
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Affiliation(s)
- Bernd Schröder
- Department of Physiology, School of Veterinary Medicine, Bischofsholer Damm 15, 30173 Hannover, Germany.
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Zhou Y, Yang W, Kirberger M, Lee HW, Ayalasomayajula G, Yang JJ. Prediction of EF-hand calcium-binding proteins and analysis of bacterial EF-hand proteins. Proteins 2007; 65:643-55. [PMID: 16981205 DOI: 10.1002/prot.21139] [Citation(s) in RCA: 114] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
The EF-hand protein with a helix-loop-helix Ca(2+) binding motif constitutes one of the largest protein families and is involved in numerous biological processes. To facilitate the understanding of the role of Ca(2+) in biological systems using genomic information, we report, herein, our improvement on the pattern search method for the identification of EF-hand and EF-like Ca(2+)-binding proteins. The canonical EF-hand patterns are modified to cater to different flanking structural elements. In addition, on the basis of the conserved sequence of both the N- and C-terminal EF-hands within S100 and S100-like proteins, a new signature profile has been established to allow for the identification of pseudo EF-hand and S100 proteins from genomic information. The new patterns have a positive predictive value of 99% and a sensitivity of 96% for pseudo EF-hands. Furthermore, using the developed patterns, we have identified zero pseudo EF-hand motif and 467 canonical EF-hand Ca(2+) binding motifs with diverse cellular functions in the bacteria genome. The prediction results imply that pseudo EF-hand motifs are phylogenetically younger than canonical EF-hand motifs. Our prediction of Ca(2+) binding motifs provides not only an insight into the role of Ca(2+) and Ca(2+)-binding proteins in bacterial systems, but also a way to explore and define the role of Ca(2+) in other biological systems (calciomics).
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Affiliation(s)
- Yubin Zhou
- Department of Chemistry, Georgia State University, Atlanta, Georgia 30303, USA
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15
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Lee WJ, Monteith GR, Roberts-Thomson SJ. Calcium transport and signaling in the mammary gland: targets for breast cancer. Biochim Biophys Acta Rev Cancer 2005; 1765:235-55. [PMID: 16410040 DOI: 10.1016/j.bbcan.2005.12.001] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2005] [Revised: 12/01/2005] [Accepted: 12/01/2005] [Indexed: 12/30/2022]
Abstract
The mammary gland is subjected to extensive calcium loads during lactation to support the requirements of milk calcium enrichment. Despite the indispensable nature of calcium homeostasis and signaling in regulating numerous biological functions, the mechanisms by which systemic calcium is transported into milk by the mammary gland are far from completely understood. Furthermore, the implications of calcium signaling in terms of regulating proliferation, differentiation and apoptosis in the breast are currently uncertain. Deregulation of calcium homeostasis and signaling is associated with mammary gland pathophysiology and as such, calcium transporters, channels and binding proteins represent potential drug targets for the treatment of breast cancer.
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Affiliation(s)
- Won Jae Lee
- School of Pharmacy, Steele Building, The University of Queensland, Brisbane 4072, Australia
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Luu KC, Nie GY, Hampton A, Fu GQ, Liu YX, Salamonsen LA. Endometrial expression of calbindin (CaBP)-d28k but not CaBP-d9k in primates implies evolutionary changes and functional redundancy of calbindins at implantation. Reproduction 2004; 128:433-41. [PMID: 15454638 DOI: 10.1530/rep.1.00226] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The endometrium is hostile to embryo implantation except during the ‘window of receptivity’. A change in endometrial gene expression is required for the development of receptivity. Calbindin-d9k (CaBP-d9k) and calbindin-d28k (CaBP-d28k) are proteins possessing EF-hand motifs which have high affinity for Ca2+ions. Previously, it has been demonstrated that, in mouse endometrium, the expression of both calbindins is highly regulated during implantation and that both proteins play critical but functionally redundant roles at implantation. This study was the first to determine the expression of these two calbindins in the human and rhesus monkey endometrium. Initial RT-PCR analysis demonstrated that CaBP-d28k but not CaBP-d9k mRNA expression is detectable in the endometrium of both species. Western blot analysis confirmed the presence of immuno-reactive CaBP-d28k protein in the primate endometrium. Furthermore, the endometrial expression pattern of CaBP-d28k mRNA and protein was examined by Northern blot analysis and immunohistochemistry respectively in both species across the menstrual cycle and during early pregnancy. Semi-quantitative statistical analysis of the immunohistochemistry results revealed that, in the human, CaBP-d28k protein expression was maximal in luminal and glandular epithelium during the mid-secretory phase, coinciding with the time when the endometrium is receptive to embryo implantation. Expression in rhesus monkey showed a similar trend. These results suggest that, in the primate endometrium, only CaBP-d28k is expressed and that the specific regulation of this calbindin is potentially important for the establishment of uterine receptivity.
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Affiliation(s)
- Kien C Luu
- Prince Henry's Institute of Medical Research, Clayton, Victoria 3168, Australia
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Kamm K, Hoppe S, Breves G, Schröder B, Schemann M. Effects of the probiotic yeast Saccharomyces boulardii on the neurochemistry of myenteric neurones in pig jejunum. Neurogastroenterol Motil 2004; 16:53-60. [PMID: 14764205 DOI: 10.1046/j.1365-2982.2003.00458.x] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
We studied the effects of food supplementation with Saccharomyces boulardii (S. boulardii; synonym S. cerevisiae HANSEN CBS 5926; 1 g per day for 9 days) on the presence and co-localization patterns of neuronal markers in myenteric neurones of the pig jejunum. The pan neuronal marker Hu revealed no change in the number of neuronal cell bodies per ganglion (37 +/- 7 in control vs 34 +/- 9 in the S. boulardii group). Ranked by size the following cell populations were identified: choline acetyltransferase (ChAT), calbindin-28k (CALB), substance P (SP), neurofilament 160 kD (NF-160), vasoactive intestinal polypeptide (VIP), nitric oxide synthase (NOS), calcitonin gene-related peptide (CGRP), calretinin (CALRET). We found a significant decrease in the number of CALB myenteric neurones in animals which received S. boulardii supplemented diet. None of the other neuronal markers revealed any difference between controls and S. boulardii treated animals. The study reports transmitter-localization patterns in the myenteric plexus of the pig jejunum and provides evidence that changes in the neurochemistry of enteric neurones occur with S. boulardii supplemented diet. Although only CALB expression was altered and the functional significance of this finding remains unknown, our study identified a possible new effector level of probiotics in the gut.
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Affiliation(s)
- K Kamm
- Department of Physiology, School of Veterinary Medicine, Bischofsholer Damm, Hannover, Germany
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Ohta A, Motohashi Y, Sakai K, Hirayama M, Adachi T, Sakuma K. Dietary fructooligosaccharides increase calcium absorption and levels of mucosal calbindin-D9k in the large intestine of gastrectomized rats. Scand J Gastroenterol 1998; 33:1062-8. [PMID: 9829361 DOI: 10.1080/003655298750026769] [Citation(s) in RCA: 49] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
BACKGROUND In gastrectomized rats intestinal calcium absorption and bone calcium levels markedly decrease and the levels recover as a result of feeding fructooligosaccharides (FOS). In the present study we examined the effects of gastrectomy and dietary FOS on intestinal calbindin-D9k (CaBP) levels. METHODS One group of rats was subjected to a sham operation and fed a control diet. Two other groups of rats were gastrectomized, and those in one group were fed the control diet, whereas those in the other group were fed a diet containing 10% FOS. Intestinal calcium, magnesium, and phosphorus absorption levels and intestinal CaBP levels were measured. RESULTS Gastrectomy increased CaBP levels in the distal small intestine, cecum, and colorectum but markedly decreased calcium absorption. Dietary FOS increased CaBP levels in the cecum and colorectum in the case of gastrectomized rats and improved calcium absorption. CONCLUSIONS The results suggest that dietary FOS not only improve intestinal calcium absorption but also serve to maintain local calcium homeostasis in the intestine by increasing mucosal CaBP levels in the large intestine of gastrectomized rats.
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Affiliation(s)
- A Ohta
- Nutritional Science Center, Bioscience Laboratories, Meiji Seika Kaisha, Ltd., Sakado, Saitama, Japan
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Schroeder B, Dahl MR, Breves G. Duodenal Ca2+ absorption is not stimulated by calcitriol during early postnatal development of pigs. THE AMERICAN JOURNAL OF PHYSIOLOGY 1998; 275:G305-13. [PMID: 9688658 DOI: 10.1152/ajpgi.1998.275.2.g305] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
The role of calcitriol in stimulating intestinal active Ca2+ absorption during postnatal life was studied in newborn, suckling, and weaned control (Con) piglets and piglets suffering from inherited calcitriol deficiency (Def piglets). In addition, a group of Def piglets was treated with vitamin D3 (Def-D3 piglets), which normalized plasma calcitriol levels. Regardless of age, duodenal calbindin-D9k concentrations ranged between 1,839 and 2,846 microg/g mucosa in Con piglets, between 821 and 1,219 microg/g mucosa in Def piglets, and between 2,960 and 3,692 microg/g mucosa in Def-D3 animals. In weaned animals, active Ca2+ absorption as calculated from in vitro 45Ca2+ flux rate measurements in Ussing chambers could be related to calbindin-D9k levels. Thus active Ca2+ absorption was completely absent in Def animals but was reconstituted in Def-D3 animals. In contrast, in newborn Def piglets active Ca2+ absorption functioned normally despite the low plasma calcitriol and mucosal calbindin-D9k levels and could not be affected by treatment with vitamin D3. Similar results were obtained from suckling Def piglets. The microtubule-disrupting agent colchicine caused significant inhibition of transepithelial net Ca2+ absorption in duodenal epithelia from newborn piglets without exerting an effect in suckling and weaned animals. Colchicine had no effect on Ca2+ uptake across the brush border membrane of mucosal enterocytes or on glucose-dependent electrogenic net ion flux rates in duodenal preparations from newborn Con piglets. In conclusion, our findings reveal intestinal active Ca2+ absorption during early postnatal life of pigs that involves calcitriol-independent mechanisms and that may include intact microtubule actions.
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Affiliation(s)
- B Schroeder
- Department of Physiology, School of Veterinary Medicine, D-30173 Hannover, Germany
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Schröder B, Hattenhauer O, Breves G. Phosphate transport in pig proximal small intestines during postnatal development: lack of modulation by calcitriol. Endocrinology 1998; 139:1500-7. [PMID: 9528927 DOI: 10.1210/endo.139.4.5922] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The role of calcitriol in the intestinal absorption of inorganic phosphate (Pi) during postnatal development was studied in newborn [<1 week postpartum (pp)], suckling (3-4 weeks pp), and weaned (>6 weeks pp) control piglets (con) and piglets suffering from inherited calcitriol deficiency (def). In addition, a number of def piglets were treated with vitamin D3 (def-D3). Regardless of age, plasma calcitriol concentrations in def piglets were unphysiologically low (16-21 pg/ml) and differed significantly from those in respective con animals (60-69 pg/ml) and vitamin D3-treated def piglets (50-56 pg/ml). However, newborn and suckling def piglets had normal Ca (approximately 3.0 mmol/liter) and Pi (approximately 2.8 mmol/liter) plasma levels. Def piglets became hypocalcemic (1.9 mmol/liter) and hypophosphatemic (1.9 mmol/liter) between 4-6 weeks pp. Treatment with vitamin D3 significantly increased plasma Ca (3.2 mmol/liter) and Pi (2.7 mmol/liter) levels in weaned def animals. Regardless of calcitriol status, net Pi flux rates (active Pi absorption, as determined with the in vitro Ussing-chamber technique) from the upper small intestines was maximal at birth [170-224 nmol/(cm2 x h)] and decreased by approximately 80% during the first week of life before remaining constant [30-50 nmol/(cm2 x h)] during the following development. In weaned def piglets, net Pi flux rates were significantly lower by about 80% compared with those in con animals. Treatment of def piglets with vitamin D3 had no effect in newborn and suckling animals but reconstituted net Pi flux rates to normal values at weaning age. Age-dependent and calcitriol-mediated changes in net Pi flux rates were paralleled by respective maximum velocity values of Na+-dependent Pi uptake across the brush border membrane of the enterocytes (newborn piglets, 1.9-2.2 nmol/(mg protein 10 sec); suckling piglets, 0.4-0.6 nmol/(mg protein x 10 sec); weaned piglets, 0.7, 0.3, and 0.7 nmol/(mg protein x 10 sec) in con, def, and def-D3 animals, respectively). These findings suggest that the apical Pi uptake represents the major rate-limiting step of the overall transepithelial Pi transport. At weaning, Na+/Pi transport across the intestinal brush-border membrane is clearly stimulated by calcitriol, but no significant effects of age or calcitriol on the Km values (0.5-0.7 mmol/liter) were observed. In conclusion, our findings reveal calcitriol-independent mechanisms for active intestinal Pi absorption during the neonatal and suckling periods. The onset of the classical calcitriol-dependent mechanism for active intestinal Pi absorption does not occur until weaning.
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Affiliation(s)
- B Schröder
- Physiologisches Institut, Tierärztliche Hochschule Hannover, Germany.
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