Effects of ascorbic acid and ascorbic acid 2‐phosphate, a long‐acting vitamin C derivative, on the proliferation and differentiation of human osteoblast‐like cells

Abstract

In order to investigate the effect of ascorbic acid (AsA) and ascorbic acid 2‐phosphate (Asc 2‐P), a long‐acting vitamin C derivative, on the growth and differentiation of human osteoblast‐like cells, we supplemented the culture medium of MG‐63 cells with various concentrations (0.25 to 1 mM) of these factors. Asc 2‐P significantly stimulated nascent cell growth at all concentrations in the presence of fetal bovine serum (FBS). On the other hand, AsA showed a growth repressive effect depending on its concentration, and that of FBS. Asc 2‐P also increased expression of osteoblast differentiation markers, such as collagen synthesis and alkaline phosphatase (ALP) activity. These stimulative activities of Asc 2‐P were attenuated by inhibitors of collagen synthesis, indicating that these effects were dependent on collagen synthesis. Electron micrographs of the cells showed the formation of a three‐dimensional tissue‐like structure endowed with a mature extracellular matrix in the presence of Asc 2‐P.