牙髓卟啉单胞菌脂多糖对小鼠成骨细胞增殖和分化的抑制作用

目的 观察牙髓卟啉单胞菌(Porphyromonas endodontalis,Pe)脂多糖(lipopolysaccharides,LPS)对成骨细胞MC3T3-E1增殖、碱性磷酸酶(alkaline phosphatase,ALP)活性和白细胞介素(IL)-6分泌情况的影响,探讨Pe-LPS在成骨细胞增殖与分化过程...

Inhibitory effects of Porphyromonas endodontalis lipopolysaccharides on proliferation and differentiation of mouse osteoblast

Objective To observe the effect of lipopolysaccharides (LPS) extracted from Porphyromonas endodontalis (Pe) on osteoblast cell proliferation and the activity of alkaline phosphatase (ALP) and interleukin (IL)-6 secretion and to investigate the role of Pe-LPS in osteoblast proliferation and differentiation. Methods MC3T3-E1 cells were treated with different concentrations of Pe-LPS ( 10, 25,50 mg/L)respectively. The relative growth rate(RGR) was detected by methyl thiazolyl tetrazolium (MTT)at different time point ( 12,24,48,72 h). MC3T3-E1 cells were also stimulated with 10,25 or 50 mg/L PeLPS for 6,12,24 and 48 h. The activity of ALP was detected by enzyme kinetics assay and the secretion of IL-6 was detected by enzyme-linked immunosorbent assay ( ELISA ). Results After the stimulation with 25 or 50 mg/L Pe-LPS for 72 h, the RGR of MC3T3-E1 cells descend to 87.46% and 71.12%. The ALP activities of MC3T3-El cells were inhibited obviously ( P ＜ 0. 05 ) after the stimulation of different concentrations( 10, 25, 50 mg/L) Pe-LPS for more than 24 hours. ELISA result showed that IL-6 increased to 32. 21 ng/L treated with the 25 mg/L Pe-LPS for 6 h, 25 mg/L Pe-LPS gradually increased the expression of IL-6 from the ELISA results. Conclusions Pe-LPS can induce the secretion of IL-6 in MC3T3-E1 and decrease the ALP activities of MC3T3-E1, the differentiation of osteoblasts was inhibited. with the long-time toxicity action of Pe-LPS, the proliferation rate of MC3T3-E1 also markedly decreased.