[Effect of tobacco extracts on human gingival fibroblasts' proliferation and fibronectin expression]

To investigate the influence and mechanism of smokeless tobacco (ST) extracts on proliferation and fibronectin expression of human gingival fibroblasts (HGFs) adhered to titanium plates.

The cultured primary HGFs with ST of different concentrations for a period of 2h and 2, 4, 6, 8 d was separately conducted; the cell proliferation and the adhesion was assayed using CCK-8 method; enzyme-linked immunosorbent assay was used to determine the content of supernatant fibronectin (FN) at different times. The data was analyzed with SPSS 19.0 software package.

With the increase of ST concentration, the cell adherence rate decreased accordingly. With ST concentration of 5.0 g/L and 10 g/L, the adhesion rate was (34.316±7.725)% and (25.478±10.651)%, respectively, which was significantly lower than that of the control group (100%) (P<0.01). Cell proliferation on the titanium plate started at 2 d and 4 d and the cell abundance of the control group was significantly greater than that of ST group (P<0.05) with concentrations of 2.5, 5.0, 10 g/L; The cell abundance of the control group was significantly greater than that of ST group (P<0.05) with concentrations of 0.625-10 g/L on the 6th and 8th day. In 0.625, 1.25, 2.5 g/L ST group, FN concentration was (69.352±31.640), (23.595±8.625) and (7.292±2.865) ng/mL, respectively, which was significantly lower than that of the control group (142.188 ± 28.126) ng/mL (P<0.05).

ST can significantly inhibit the proliferation and adhesion of HGFs on pure titanium surface, and the mechanism may be related to decrease of FN secreted by HGFs.