生殖支原体脂质相关膜蛋白激活核因子κB诱导人单核细胞表达前炎症细胞因子及凋亡

Mycoplasma genitalium lipid-associated membrane proteins induce human monocytic cell express proinflammatory cytokines and apoptosis by activating nuclear factor κB

摘要:

为了解生殖支原体(Mg)潜在的致病性及其脂质相关膜蛋白(LAMPs)诱导人单核细胞(THP-1)凋亡及表达前炎症细胞因子(CKs)的分子机制,用Mg提取的LAMPs刺激THP-1细胞,以ELISA法和RT-PCR方法分析CKs产生和其mRNA的表达。不同试实验组的细胞经AnnexinV联合PI染色后通过流式细胞仪检测细胞凋亡。采用EMSA方法检测LAMPs处理的THP-1细胞中核转录因子kappaB(NF-κB)的激活,并分析NF-κB抑制剂二硫代氨基甲酸吡咯烷(pyrrolidine dithiocoarbamate,PDTC)对LAMPs处理的THP-1细胞产生CKs的量和其mRNA表达及细胞凋亡的影响。LAMPs能以时间和剂量依赖方式刺激THP-1细胞产生TNF-α、IL-1β和IL-6,且能激活NF-κB诱导THP-1细胞表达CKs的mRNA及发生凋亡,PDTC能显著抑制CKs的mRNA表达水平和细胞凋亡。由于LAMPs能激活NF-κB诱导THP-1细胞表达CKs及产生细胞凋亡,因而可能是一个重要的致病因素。

Abstract:

Designed to investigate the potential pathogenicity of Mycoplasma genitalium (M. genitalium) and its molecular mechanisms responsible for the induction of proinflammatory cytokines gene expression in human monocytic cells (THP-1) stimulated by lipid-associated membrane proteins (LAMPs) prepared from M. genitalium. THP-1 cells were stimulated with LAMPs to analyze the production of proinflammatory cytokines and the expression of mRNA was detected by RT-PCR. Cell apoptosis was detected in THP-1 cells by Annexin V-propidium iodide staining. The activity of transcriptional factors, NF-κB, was examined in THP-1 cells treated with LAMPs by EMSA. The effects of pyrrolidine dithiocarbamate (PDTC), an inhibitor of NF-κB, on the production of proinflammatory cytokines, the expression of mRNA and apoptosis were also examined in THP-1 cells treated with LAMPs. M.genitalium LAMPs stimulate THP-1 cells to produce TNF-α、IL-1β and IL-6 in dose- and time-dependent manner. The mRNA levels and cell apoptosis are also downregulated in response to LAMPs stimulation and inhibited by PDTC treatment. M.genitalium LAMPs are found to trigger NF-κB activation, a possible mechanism for the induction of mRNA expression and the cell apoptosis. This study demonstrated that M.genitalium may be an important etiological factor of certain disease due to the ability of LAMPs to stimulated the expression of mRNA and apoptosis, which is probably mediated through the activation of NF-κB.