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Haffner‐Luntzer M, Heilmann A, Heidler V, Liedert A, Schinke T, Amling M, Yorgan TA, vom Scheidt A, Ignatius A. Hypochlorhydria-induced calcium malabsorption does not affect fracture healing but increases post-traumatic bone loss in the intact skeleton. J Orthop Res 2016; 34:1914-1921. [PMID: 26945509 PMCID: PMC5157780 DOI: 10.1002/jor.23221] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/20/2015] [Accepted: 02/29/2016] [Indexed: 02/04/2023]
Abstract
Efficient calcium absorption is essential for skeletal health. Patients with impaired gastric acidification display low bone mass and increased fracture risk because calcium absorption is dependent on gastric pH. We investigated fracture healing and post-traumatic bone turnover in mice deficient in Cckbr, encoding a gastrin receptor that affects acid secretion by parietal cells. Cckbr-/- mice display hypochlorhydria, calcium malabsorption, and osteopenia. Cckbr-/- and wildtype (WT) mice received a femur osteotomy and were fed either a standard or calcium-enriched diet. Healed and intact bones were assessed by biomechanical testing, histomorphometry, micro-computed tomography, and quantitative backscattering. Parathyroid hormone (PTH) serum levels were determined by enzyme-linked immunosorbent assay. Fracture healing was unaffected in Cckbr-/- mice. However, Cckbr-/- mice displayed increased calcium mobilization from the intact skeleton during bone healing, confirmed by significantly elevated PTH levels and osteoclast numbers compared to WT mice. Calcium supplementation significantly reduced secondary hyperparathyroidism and bone resorption in the intact skeleton in both genotypes, but more efficiently in WT mice. Furthermore, calcium administration improved bone healing in WT mice, indicated by significantly increased mechanical properties and bone mineral density of the fracture callus, whereas it had no significant effect in Cckbr-/- mice. Therefore, under conditions of hypochlorhydria-induced calcium malabsorption, calcium, which is essential for callus mineralization, appears to be increasingly mobilized from the intact skeleton in favor of fracture healing. Calcium supplementation during fracture healing prevented systemic calcium mobilization, thereby maintaining bone mass and improving fracture healing in healthy individuals whereas the effect was limited by gastric hypochlorhydria. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 34:1914-1921, 2016.
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Affiliation(s)
- Melanie Haffner‐Luntzer
- Institute of Orthopedic Research and BiomechanicsUniversity Medical Center UlmHelmholtzstraße 14Ulm89081Germany
| | - Aline Heilmann
- Institute of Orthopedic Research and BiomechanicsUniversity Medical Center UlmHelmholtzstraße 14Ulm89081Germany
| | - Verena Heidler
- Institute of Orthopedic Research and BiomechanicsUniversity Medical Center UlmHelmholtzstraße 14Ulm89081Germany
| | - Astrid Liedert
- Institute of Orthopedic Research and BiomechanicsUniversity Medical Center UlmHelmholtzstraße 14Ulm89081Germany
| | - Thorsten Schinke
- Department of Osteology and BiomechanicsUniversity Medical Center Hamburg‐EppendorfMartinistraße 52Hamburg20246Germany
| | - Michael Amling
- Department of Osteology and BiomechanicsUniversity Medical Center Hamburg‐EppendorfMartinistraße 52Hamburg20246Germany
| | - Timur Alexander Yorgan
- Department of Osteology and BiomechanicsUniversity Medical Center Hamburg‐EppendorfMartinistraße 52Hamburg20246Germany
| | - Annika vom Scheidt
- Department of Osteology and BiomechanicsUniversity Medical Center Hamburg‐EppendorfMartinistraße 52Hamburg20246Germany
| | - Anita Ignatius
- Institute of Orthopedic Research and BiomechanicsUniversity Medical Center UlmHelmholtzstraße 14Ulm89081Germany
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Kraidith K, Svasti S, Teerapornpuntakit J, Vadolas J, Chaimana R, Lapmanee S, Suntornsaratoon P, Krishnamra N, Fucharoen S, Charoenphandhu N. Hepcidin and 1,25(OH)2D3 effectively restore Ca2+ transport in β-thalassemic mice: reciprocal phenomenon of Fe2+ and Ca2+ absorption. Am J Physiol Endocrinol Metab 2016; 311:E214-23. [PMID: 27245334 DOI: 10.1152/ajpendo.00067.2016] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/22/2016] [Accepted: 05/23/2016] [Indexed: 12/15/2022]
Abstract
Previously, β-thalassemia, an inherited anemic disorder with iron overload caused by loss-of-function mutation of β-globin gene, has been reported to induce osteopenia and impaired whole body calcium metabolism, but the pathogenesis of aberrant calcium homeostasis remains elusive. Herein, we investigated how β-thalassemia impaired intestinal calcium absorption and whether it could be restored by administration of 1,25-dihydroxyvitamin D3 [1,25(OH)2D3] or hepcidin, the latter of which was the liver-derived antagonist of intestinal iron absorption. The results showed that, in hemizygous β-globin knockout (BKO) mice, the duodenal calcium transport was lower than that in wild-type littermates, and severity was especially pronounced in female mice. Both active and passive duodenal calcium fluxes in BKO mice were found to be less than those in normal mice. This impaired calcium transport could be restored by 7-day 1,25(OH)2D3 treatment. The 1,25(OH)2D3-induced calcium transport was diminished by inhibitors of calcium transporters, e.g., L-type calcium channel, NCX1, and PMCA1b, as well as vesicular transport inhibitors. Interestingly, the duodenal calcium transport exhibited an inverse correlation with transepithelial iron transport, which was markedly enhanced in thalassemic mice. Thus, 3-day subcutaneous hepcidin injection and acute direct hepcidin exposure in the Ussing chamber were capable of restoring the thalassemia-associated impairment of calcium transport; however, the positive effect of hepcidin on calcium transport was completely blocked by proteasome inhibitors MG132 and bortezomib. In conclusion, both 1,25(OH)2D3 and hepcidin could be used to alleviate the β-thalassemia-associated impairment of calcium absorption. Therefore, our study has shed light on the development of a treatment strategy to rescue calcium dysregulation in β-thalassemia.
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Affiliation(s)
- Kamonshanok Kraidith
- Center of Calcium and Bone Research, Faculty of Science, Mahidol University, Bangkok, Thailand; Department of Physiology, Faculty of Science, Mahidol University, Bangkok, Thailand
| | - Saovaros Svasti
- Thalassemia Research Center, Institute of Molecular Biosciences, Mahidol University, Nakhon Pathom, Thailand; and
| | | | - Jim Vadolas
- Cell and Gene Therapy Research Group, Murdoch Childrens Research Institute, Royal Children's Hospital, Melbourne, Australia
| | - Rattana Chaimana
- Center of Calcium and Bone Research, Faculty of Science, Mahidol University, Bangkok, Thailand; Department of Physiology, Faculty of Science, Mahidol University, Bangkok, Thailand
| | - Sarawut Lapmanee
- Center of Calcium and Bone Research, Faculty of Science, Mahidol University, Bangkok, Thailand; Department of Physiology, Faculty of Science, Mahidol University, Bangkok, Thailand
| | - Panan Suntornsaratoon
- Center of Calcium and Bone Research, Faculty of Science, Mahidol University, Bangkok, Thailand
| | - Nateetip Krishnamra
- Center of Calcium and Bone Research, Faculty of Science, Mahidol University, Bangkok, Thailand; Department of Physiology, Faculty of Science, Mahidol University, Bangkok, Thailand
| | - Suthat Fucharoen
- Thalassemia Research Center, Institute of Molecular Biosciences, Mahidol University, Nakhon Pathom, Thailand; and
| | - Narattaphol Charoenphandhu
- Center of Calcium and Bone Research, Faculty of Science, Mahidol University, Bangkok, Thailand; Department of Physiology, Faculty of Science, Mahidol University, Bangkok, Thailand;
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