Abstract: To observe the effect of icariin on human periodontal ligament cells (hPDLCs) differentiation to osteoblast gene expression. Methods: The fifth generation of the cultured hPDLCs was added with the concentration of 0.01 mg/L icariin, and the added osteogenic medium used as blank control group, alizarin red staining of icariin on human periodontal ligament cells was observed for 21 days; the 2, 4, and 6 days of Q-PCR quantitative analysis of icariin on human periodontal ligament cells were made for osteogenesis gene alkaline phosphatase (ALP), type I collagen and osteocalcin (OC) gene expression. Results: For the 21 days, alizarin red staining icariin group formed more mineralized nodules; on the 2^nd, 4^th, and 6^th days, the group of icariin promoted the expression of ALP and OC mRNA, reached the peak value on day 6, compared with the control group with significant difference (20.15±6.67 vs. 7.90±0.71, 4.13±0.56 vs. 3.55±0.08, P<0.01). The second day, the highest expression of type Ⅰ collagen appeared, then decreased gradually after, statistically compared with the control group (P<0.05). Conclusion: Icariin can promote the human periodontal ligament cells differentiation to osteoblast, and promote the osteogenesis gene expression.

Key words: Icariin, Periodontal ligament, Cell Differentiation, Osteogenesis