The Effects of Minocycline on Cultured Human Periodontal Ligament Fibroblasts

Objectives:Minocycline is an effective antimicrobial as well as an ideal root conditioner. Moreover, evidence suggests that minocycline can influence cellular activity of periodontal mesenchymal cells and gingival epithelial cells. The purpose of this present study was to evaluate the modulation of human periodontal ligament(HPDL) cells proliferation, protein synthesis and DNA synthesis by minocycline. Methods:HPDL cells were cultured and increasing concentrations of minocycline(1,5,20,100,500,2500ug/ml) were individually added to the medium. After cultured for 2 days,cells were then assayed for proliferation and biosynthesis .Results: At doses not exceeding 100ug/ml, cell morphology was normal. Meanwhile, minocycline promoted HPDL cells proliferation, protein synthesis and DNA synthesis in a dose-dependent manner over a concentration range of 5 to 100ug/ml, with a maximal response at a concentration of 100ug/ml, which enhanced cellular activity significantly higher than control group(P©‚0.01). However, higher concentrations of minocycline resulted in a cytocidal effect. Conclusions:This study demonstrates that at concentrations not beyond 100ug/ml, minocycline could promote periodontal connective tissue repair and regeneration by stimulating HPDL cells bioactivity.