Effect of Dexamethasone on the Expression of Interleukin?6 and Interleukin?8 in Human Periodontal Ligament Cells / 中国医科大学学报

ABSTRACT

Objective To explore the effect of dexamethasone(Dex)treatment on the expression of interleukin(IL)?6 and IL?8 in human peri?odontal ligament cells(hPDLCs). Methods hPDLCs were subjected to one of the following treatments for 24 h or 48 h10-9 mol/L Dex;10-6 mol/L Dex;10μg/mL Porphyromonas gingivalis(P. g)?lipopolysaccharide(LPS);10-9 mol/L Dex+10μg/mL P. g?LPS;10-6 mol/L Dex+10μg/mL P. g?LPS;or 0.1%absolute ethyl alcohol(control). Protein and mRNA expression was detected using ELISA and real?time PCR ,respectively. Results At 24 h and at 48 h,IL?6 and IL?8 protein expression in the 10-9 mol/L Dex?and 10-6 mol/L Dex?treated groups was significantly lower than that in the control group(P<0.05). At 48 h,IL?6 mRNA expression in the 10-9 mol/L Dex?and 10-6 mol/L Dex?treated groups was signifi?cantly lower than that in the control group(P<0.05),while IL?8 mRNA expression in the 10-6 mol/L Dex?treated group was significantly higher than that in the control group(P<0.05). At 24 h and at 48 h,IL?6 protein and mRNA expression in the 10-9 mol/L Dex+10μg/mL P. g?LPS?treated group and the 10-6 mol/L Dex+10μg/mL P. g?LPS?treated group was significantly lower than that in the 10μg/mL P. g?LPS?treated group (P<0.05). At 24 h,IL?8 protein expression in the 10-9 mol/L Dex+10μg/mL P. g?LPS?treated group and the 10-6 mol/L Dex+10μg/mL P. g?LPS?treated group was significantly lower than that in the 10μg/mL P. g?LPS?treated group(P<0.05),while no such significant difference exist?ed at 48 h. At 48 h,IL?8 mRNA expression in the 10-6 mol/L Dex+10μg/mL P. g?LPS?treated group was significantly higher than that in the 10μg/mL P. g?LPS?treated group(P<0.05). Conclusion Dex inhibits the innate and P. g?LPS?induced expression of IL?6 in hPDLCs. However, Dex exerts profound effects on IL?8 expression,and treatment with high doses of Dex may promote IL?8 expression over an extended period.