Vitamin C Research Today is a free monthly online journal that collates and summarizes the latest research about Vitamin C, including details on benefits, dosage, supplements, information. | ||||||||
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Ascorbic acid promotes osteoclastogenesis from embryonic stem cells.Tsuneto M, Yamazaki H, Yoshino M, Yamada T, Hayashi S Division of Immunology, Department of Molecular and Cellular Biology, School of Life Science, Faculty of Medicine, Tottori University, Yonago, Tottori 683-8503, Japan. tsune13@grape.med.tottori-u.ac.jp Ascorbic acid (AA) is known to regulate cell differentiation; however, the effects of AA on osteoclastogenesis, especially on its early stages, remain unclear. To examine the effects of AA throughout the process of osteoclast development, we established a culture system in which tartrate-resistant acid phosphate (TRAP)-positive osteoclasts were induced from embryonic stem cells without stromal cell lines. In this culture system, the number of TRAP-positive cells was strongly increased by the addition of AA during the development of osteoclast precursors, and reducing agents, 2-mercaptoethanol, monothioglycerol, and dithiothreitol, failed to substitute for AA. The effect of AA was stronger when it was added during the initial 4 days during the development of mesodermal cells than when it was added during the last 4 days. On day 4 of the culture period, AA increased the total cell recovery and frequency of osteoclast precursors. Magnetic cell sorting using anti-Flk-1 antibody enriched osteoclast precursors on day 4, and the proportion of Flk-1-positive cells but not that of platelet-derived growth factor receptor alpha-positive cells was increased by the addition of AA. These results suggest that AA might promote osteoclastogenesis of ES cells through increasing Flk-1-positive cells, which then give rise to osteoclast precursors. Published 30 August 2005 in Biochem Biophys Res Commun, 335(4): 1239-46.
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