title: Vitamin C-sulfate inhibits mineralization in chondrocyte cultures: a caveat.
abstract: Differentiating chick limb-bud mesenchymal cell micro-mass cultures routinely mineralize in the presence of 10% fetal calf serum, antibiotics, 4 mM inorganic phosphate (or 2.5 mM beta-glycerophosphate), 0.3 mg/ml glutamine and either 25 microg/ml vitamin C or 5-12 microg/ml vitamin C-sulfate. The failure of these cultures to produce a mineralized matrix (assessed by electron microscopy, 45Ca uptake and Fourier transform infrared microscopy) led to the evaluation of each of these additives. We report here that the "stable" vitamin C-sulfate (ascorbic acid-2-sulfate) causes increased sulfate incorporation into the cartilage matrix. Furthermore, the release of sulfate from the vitamin C derivative appears to be responsible for the inhibition of mineral deposition, as demonstrated in cultures with equimolar amounts of vitamin C and sodium sulfate.
authors.affiliation: Mineralized Tissues Research Section, Research Division, The Hospital for Special Surgery, 535 East 70th Street, New York, NY 10021, USA. boskeya@hss.edu
authors.forename: A L
authors.initials: AL
authors.lastname: Boskey
authors.forename: R D
authors.initials: RD
authors.lastname: Blank
authors.forename: S B
authors.initials: SB
authors.lastname: Doty
mesh_terms: D000469:Alkaline Phosphatase / Q000378:metabolism; D000818:Animals; D001205:Ascorbic Acid / Q000031:analogs & derivatives* / Q000378:metabolism* / Q000494:pharmacology; D002113:Calcification, Physiologic / Q000187:drug effects / Q000502:physiology*; D002478:Cells, Cultured; D002642:Chick Embryo; D019902:Chondrocytes / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D006909:Hydroxyproline / Q000378:metabolism; D011509:Proteoglycans / Q000378:metabolism
chemical_list: D011509:Proteoglycans; C001956:ascorbic acid 2-sulfate; D000469:Alkaline Phosphatase; D001205:Ascorbic Acid; D006909:Hydroxyproline