The role of vitamin K2 on osteoblastic functions by using stem cell model.

Vitamin K2 (MK4) functions were investigated by using the induced skin cell into osteoblast compared with the control media. The real time PCR measured gene expression in both cultures at the fourth, seventh, fourteenth, twenty first, twenty eighth, thirty fifth and forty second days of culture. The gene expressions of osteocalcin, osteonectin, osteopontin, bone sialoprotein, CBFA1, Interleukin-6, Estrogen receptors and collagen type) were monitored by real time PCR. MK4 had strong power to stimulate gene expression of osteocalcin and osteonectin after one week of culture but MK4 showed weak action on gene of osteopontin, bone sialoprotein and interleukin-6. The gene of estrogens showed the marked expression of estrogen receptor beta at the fourteenth day of culture while estrogen receptor alpha did not respond. MK4 could stimulate genes of RANKL and collagen type 1. This study supported the action of vitamin K2 for enhancing the bone matrix.