Parathyroid hormone enhances osteoblast differentiation from human skin derived precursor cells in vitro.

Parathyroid hormone (PTH), a new effective treatment for osteoporosis patients which promotes the anabolic effect in vivo, can enhance the differentiation of osteoblasts derived from the human skin-derived precursor cells (hSKPs) in vitro culture. This research investigated the effects of PTH by studying the gene expressions and other markers of osteoblast differentiation along with the induction of hSKPs to osteoblast in two experiment groups, i.e. the osteogenic induction medium (OM) only and the OM plus PTH (OM + PTH). The results of each type were compared between these two groups. Both groups expressed the Cbfa1 gene, a regulator of osteoblasts and also one of the most osteoblast specific genes. The findings were that the OM + PTH group showed more intense alkaline phosphatase staining than the other. The gene expressions of protein showing the mature osteoblasts like osteocalcin (OCN) and bone sialoprotein (BSP) in the OM + PTH group expressed higher and faster (Day 14) than the OM group. Moreover, the gene expression of osteoprotegerin (OPG) possessing the protein produced by the mature osteoblasts showed a higher level in the OM + PTH group on the same day as OCN and BSP occurred. This protein performs a function in inhibiting osteoclast maturation. The present study found that PTH enhanced the differentiation of osteoblasts derived from hSKPs by promoting the maturation of osteoblasts in vitro. It possibly concerns with the anabolic effect of PTH in a treatment for osteoporosis patients. Additionally, hSKPs are the interesting sources for osteoporosis treatments when combining with PTH.