Effects of Vitamin E on the Osteoblast Differentiation

抄録

Vitamin E is thought to affect bone formation and bone remodeling. In this study, we investigated the effects of vitamin E (α-tocopherol and δ-tocopherol) on the osteoblasts isolated from rat calvariae. At 4 and 7 days (Day 4 and 7) after induction of osteoblastic differentiation, treatment of α-tocopherol (100 and 200 μM) and δ-tocopherol (2 and 20 μM) for 3 days significantly decreased alkaline phophatase activity of the cultured osteoblasts. At Day 14, however, no significant change was detected in ALP activity and expression of bone sialoprotein mRNA in the osteoblasts treated with α-tocopherol or δ-tocopherol for 3 days. Expression of osteocalcin mRNA was decreased by treatment of α-tocopherol (100 and 200 μM) and δ-tocopherol (2 and 20 μM) at Day 4 and 7. At Day 14, expression of osteocalcin mRNA was decreased only with treatment of 200 μM α-tocopherol. In addition, the noncalcified nodules were decreased by treatment of α-tocopherol (200 μM) and δ-tocopherol (20 μM) at Day 7. However, treatment of α-tocopherol and δ-tocopherol showed no significant change of formation of calcified nodules at Day 14. These results indicate that vitamin E inhibits differentiation of osteoblasts especially from early stage to osteoid-producing stage.