Dietary calcium and vitamin D2 supplementation with enhanced Lentinula edodes improves osteoporosis-like symptoms and induces duodenal and renal active calcium transport gene expression in mice
- 323 Downloads
The two main sources of vitamin D3 are de novo synthesis induced by exposure to ultraviolet (UV) light from the sun, and diet. Vitamin D3 deficiency causes rickets or osteoporosis. Oak mushrooms (Lentinula edodes) that are exposed to UV radiation contain enhanced vitamin D2 and have much higher calcium content than unmodified (non-irradiated) mushrooms. Such modified edible mushrooms have been proposed as a natural alternative source of dietary vitamin D. In the current study, we have examined whether modified oak mushrooms could improve or prevent osteoporosis-like symptoms in mice fed with low calcium and vitamin D3-deficient diet. Four-week-old male mice were fed low calcium, vitamin D3-deficient diets supplemented with 5, 10, or 20% unmodified, calcium-enhanced, or calcium plus vitamin D2-enhanced oak mushrooms for 4 weeks. To assess the effects of the supplemented diets, we evaluated femur density and length, bone histology, the expression of active calcium transport genes, and serum calcium levels. Mice fed with low calcium and vitamin D3-deficient diet developed osteoporosis-like symptoms within 4 weeks. Femur density and tibia thickness were significantly higher in mice fed calcium plus vitamin D2-enhanced mushrooms, and the expression of duodenal and renal calcium transport genes was significantly induced. These results indicate that in mice, vitamin D2 and/or calcium derived from irradiated oak mushrooms may improve bone mineralization through a direct effect on the bone, and by inducing the expression of calcium-absorbing genes in the duodenum and kidney.
KeywordsL. edodes active calcium transporting genes osteoporosis vitamin D2
This work was supported by a grant (Code #20070401034011) from BioGreen 21 Program, Rural Development Administration and Ministry of Agriculture and Forestry.
- 3.Association of Official Analytical Chemists (2000) Official method of analysis of AOAC intl., 17th edn. AOAC International, Maryland, pp 40–49Google Scholar
- 11.Hoenderop JG, Nilius B, Bindels RJ (2003) Epithelial calcium channels: from identification to function and regulation. Pflugers Arch 446:304–308Google Scholar
- 15.Kumar R, Wieben E, Beecher SJ (1989) The molecular cloning of the complementary deoxyribonucleic acid for bovine vitamin D-dependent calcium-binding protein: structure of the full-length protein and evidence for homologies with other calcium-binding proteins of the troponin-C superfamily of proteins. Mol Endocrinol 3:427–432CrossRefGoogle Scholar
- 22.Mattila P, Suonpaa K, Piironen V (2000) Functional properties of edible mushrooms. Nutrition (Burbank, Los Angeles County Calif) 16:694–696Google Scholar
- 25.Peng JB, Chen XZ, Berger UV, Vassilev PM, Brown EM, Hediger MA (2000) A rat kidney-specific calcium transporter in the distal nephron. J Biol Chem 275:28186–28194Google Scholar
- 28.Roche C, Bellaton C, Pansu D, Miller A 3rd, Bronner F (1986) Localization of vitamin D-dependent active Ca2+ transport in rat duodenum and relation to CaBP. Am J Physiol 251:G314–G320Google Scholar
- 30.Trang HM, Cole DE, Rubin LA, Pierratos A, Siu S, Vieth R (1998) Evidence that vitamin D3 increases serum 25-hydroxyvitamin D more efficiently than does vitamin D2. Am J Clin Nutr 68:854–858Google Scholar
- 31.Van Cromphaut SJ, Rummens K, Stockmans I, Van Herck E, Dijcks FA, Ederveen AG, Carmeliet P, Verhaeghe J, Bouillon R, Carmeliet G (2003) Intestinal calcium transporter genes are upregulated by estrogens and the reproductive cycle through vitamin D receptor-independent mechanisms. J Bone Miner Res 18:1725–1736CrossRefGoogle Scholar
- 32.van den Berg H (1997) Bioavailability of vitamin D. Eur J Clin Nutr 51(Suppl 1):S76–S79Google Scholar
- 34.Wasserman RH, Fullmer CS (1989) On the molecular mechanism of intestinal calcium transport. Adv Exp Med Biol 249:45–65Google Scholar