Abstract:

Objective  A study was conducted to investigate the effects of Porphyromonas gingivalis lipopolysaccharide (Pg-LPS) on the expression of regulated upon activation normal T-cell expressed and secreted (RANTES) and fractalkine in human umbilical vein endothelial cells (HUVECs). Methods  HUVECs were incubated with different concentrations of Pg-LPS (200, 500, and 1 000 ng·mL⁻¹) for 1, 6, 12, and 24 h, respectively. Then real time quantitative polymerase chain reaction (RT-PCR) and enzyme-linked immunosorbent method (ELISA) were adopted to detect the protein levels and mRNA levels of RANTES and fractalkine. Results  The RANTES protein levels and mRNA levels, as well as fractalkine mRNA levels, were significantly higher in all experimental groups of 1, 6, and 12 h than in the control group (P<0.05), except the expression of RANTES mRNA in 200 ng·mL⁻¹ group of 12 h and RANTES protein in 200 ng·mL⁻¹ group of 1 h. The expression levels of RANTES mRNA and fractalkine mRNA were highest in 1 000 ng·mL⁻¹ group of 6 h and were 4.88- and 6.20-fold higher, respectively, than those in the control group. The expression levels of RANTES protein, mRNA, and fractalkine mRNA decreased 6 h after stimulation, and were significantly higher than those in the control group (P<0.05) in the 500 ng·mL⁻¹ group of 24 h. There was a significant difference between the expression of fractalkine mRNA in 1 000 ng·mL⁻¹ group of 6 and 12 h than in the control group (P<0.05). Conclusion  Pg-LPS infection might up-regulate the expression of RANTES and fractalkine in HUVEC, and such expression is important in the development of atherosclerosis.

Key words: atherosclerosis, periodontitis, chemokines, Porphyromonas gingivalis, lipopolysacchearide