牙髓卟啉单胞菌内毒素诱导成骨细胞表达炎症因子的信号通路研究

Study of signal transduction pathway in the expression of inflammatory factors stimulated by lipopolysaccharides from Porphyromonas endodontalis in osteoblasts

目的检测细胞外信号调节激酶(ERK)1/2和p38丝裂原活化蛋白激酶抑制剂对牙髓卟啉单胞菌内毒素(LPS)诱导成骨细胞白细胞介素(IL)-1β mRNA和IL-6 mRNA的影响,探讨根尖周病变牙槽骨吸收的可能病理机制。方法成骨细胞MG-63经PD98059和SB203580预处理1h后,加入牙髓卟啉单胞菌LPS作用6h,应用逆转录聚合酶链反应(RT-PCR)检测IL-1β mRNA和IL-6 mRNA的表达水平。结果PD98059预处理后,牙髓卟啉单胞菌LPS诱导MG-63表达IL-1β mRNA的水平下降。SB203580预处理后,牙髓卟啉单胞菌LPS诱导MG-63表达IL-1β mRNA和IL-6 mRNA水平均下降。结论牙髓卟啉单胞菌LPS诱导MG-63细胞表达IL-1β mRNA依赖ERK1/2和p38MAPK信号转导通路,表达IL-6 mRNA依赖p38MAPK信号转导通路。

Objective To quantify the interleukin（IL）-1β mRNA and IL-6 mRNA expression induced by lipopolysaccharides（LPS） extracted from Porphyromonas endodontalis（P.endodontalis） in osteoblasts, and to relate P. endodontalis LPS to the bone resorptive pathogenesis in the lesions of chronic apical periodontitis. Methods MG63 cells was pretreated with PD98059 or SB203580 for 1 h and then treated with P.endodontalis LPS for 6 h. The expression of IL-1β mRNA and IL-6 mRNA were detected by reverse transcription polymerase chain reaction（RT-PCR） technique. Results The production of IL-1β mRNA induced by P.endodontalis LPS decreased in osteoblasts pretreated with PD98059. Both of the production of IL-1β mRNA and IL-6 mRNA induced by P.endodontalis LPS decreased in osteoblasts pretreated with SB203580. Conclusion The synthesis of IL-1β mRNA stimulated by P.endodontalis LPS in MG63 probably occur via extracellular signal-regulated kinase（ERK） 1/2 and p38 mitogen activated protein kinase（MAPK） signal transduction system. The synthesis of IL-6 mRNA stimulated by P.endodontalis LPS in MG63 probably occur via p38MAPK signal transduction system.