[Effect of lipopolysaccharides extracted from Porphyromonas endodontalis on the expression of p38 and ERK1/2 in osteoblast].

Purpose: To investigate the effect of lipopolysaccharides (LPS) extracted from Porphyromonas endodontalis(P.e) on the expression of p38 and ERK1/2 in osteoblast.

Methods: MC3T3-E1 cells were stimulated with 10 μg/mL P.e-LPS for 0,5,15,30,60,180 min. The phosphorylation of p38 and ERK1/2 was measured by Western blot. Statistical analysis was performed using one- way ANOVA and Dunnett t test with SPSS11.0 software package.

Results: 10 μg/mL LPS could significantly activate p38 MAPK. The peak of phosphorylated p38 was detected at 5 to 30 min(P<0.01) and returned to baseline within 60 min; the level of phosphorylated ERK1/2 increased after the stimulation of LPS for 5 min and reached maximum at 15 min (P<0.01) and declined after 30 min.

Conclusions: P.e-LPS can induce the expression of p38 and ERK1/2 in osteoblast MC3T3-E1, which indicates that P.e-LPS may play an important role in osteoblast through p38 and ERK1/2.