Figure 9

Effect of high glucose (glc) on MD10-F2 pulp cell proliferation and differentiation. (a) Proliferation assay. Cells were plated in complete α-MEM that contains 5.5 mM D-glucose (normal glucose control). After 24 h, cells were placed in α-MEM with 2% FCS and incubated in the presence and absence of high D-glucose (15 or 30 mM). L-glucose (15 or 30 mM) was used as an osmotic control. Cell numbers were counted on day 4. Bar graph shows that high D-glucose (30 mM) inhibited pulp cell proliferation compared with 5 mM D-glucose (cont) and L-glucose-treated controls. Data represents three separate experiments, each performed in triplicate wells. Mean ±s.e., ^*P<0.05, D-glc (30 mM) vs Cont and L-glc controls. (b) Differentiation assay. Cultures were incubated in differentiation medium containing 5 mM D-glucose or in differentiation medium with high D-glucose or high D-glucose (15 or 30 mM). As a control, cultures were incubated without differentiation medium. Medium was changed every 2 days and, on day 12, cultures were stained with von Kossa. Control wells lack nodule formation, whereas cultures incubated in differentiation medium containing either 5 mM D-glucose or L-glucose show mineralized nodules (black color). Compared with L-glucose controls, D-glucose dramatically inhibited mineralized nodule formation. Representative of three separate experiments, each performed in triplicate wells.