Abstract:

Objective This study~carried out to investigate the effects of insulin-like growth factor- II (IGF- II)and basic fibroblast growth factor (bFGF) on osteoprotegerin (OPG) secretion of periodontal ligament cells(PDLCs).Methods Healthy human premolars extracted for orthodontic reasons from 12一14 years old donators were obtained, and periodontal tissues were col- lected and cultured to obtain PDL cells. Primary or first passage PDLCs were cloned场means of limited dilutions. PDLCs with，- teoblastic phenotypes were characterized as follows; Alkaline phosphatase activity, collagen班production and bone-like nodules formation. IGF- I1 and bFGF~added into culture media and their effects on PDLCs proliferation and OPG secretion were ob- served. The OPG concentrations in cell culture supernatants were detected by sandwich ELISA. Living cell numbers were demon- strated by MTIT test. The average levels of OPG secretion场a single cell were calculated饰dividing OPG concentration with MTT- test result. Results Both IGF- II and bFGF upregulated the mtt values(P<0.05)，but IGF-II downregulated the opg/mtt val- ues(P<0.05)，whereas bFGF had no significant effect on opg/mtt values(P>0.05).Conclusion IGF-II enhances the pro- liferation of PDL cells but prohibits OPG secretion. Although bFGF has the same effect on the proliferation of PDL cells, it has no effect on OPG secretion. Before cytokines were used to enhance periodontal regeneration, their effects on local bone balance should also be studied.

Key words: periodontium, cell-cultured, basic fibroblast growth factor, insulin-like growth factor