同型半胱氨酸对单核细胞NF-κB活化及巨噬细胞炎性蛋白-1α表达的影响  

Homocysteine induces macrophage inflammatory protein-1α expression by activating NF-κB in THP-1 monocytes

作　　者：邢玮[1] 邓仲端[1] 瞿智玲[1] 倪娟[1] 

机构地区：[1]华中科技大学同济医学院病理学系,武汉430030

出　　处：《中华病理学杂志》2005年第2期101-104,共4页Chinese Journal of Pathology

基　　金：国家自然科学基金资助项目(39730220)

摘　　要：目的　探讨同型半胱氨酸对体外培养的人单核细胞株THP -1核因子-κB(NF -κB)、抑制因子(IκB- α)活性的影响及其与巨噬细胞炎性蛋白-1α(MIP- 1α)表达上调的关系。方法　THP -1单核细胞分别用同型半胱氨酸和NF- κB抑制剂PDTC预处理后,应用Northernblot和流式细胞术分别检测MIP- 1αmRNA和蛋白的表达,并应用Western蛋白印迹进一步检测核蛋白NF -κB蛋白含量和胞质IκB -α含量。结果　与未加任何处理因素的对照组比较,MIP- 1αmRNA和蛋白在0. 1mmol/L同型半胱氨酸处理后明显增加,分别为对照组的3 .69倍和1 .16倍(P<0 .01),同时NF κBP65亚基核转位亦增加。而加入100μmol/LNF κB抑制剂PDTC预处理30min后,再用同样浓度的同型半胱氨酸刺激,则MIP -1αmRNA和蛋白表达受到明显的抑制,NF- κBP65核转位增加。单独加入PDTC对MIP -1αmRNA、蛋白表达及NF -κBP65核转位无明显影响。此外,同型半胱氨酸( 0 .1mmol/L)处理THP- 1可引起IκB -α蛋白水平显著降低, 120min后有所回升。结论　同型半胱氨酸在病理浓度可促进NF -κB活化,发生核转位,进而促进THP -1细胞表达MIP 1αmRNA和蛋白,这种作用与IκB -α蛋白磷酸化降解有关。Objective To investigate the effect of homocysteine (HCY) on activation of nuclear factor (NF-κB) and inhibitory factor IκB-α in human monocyte cell line THP-1, as well as its association with macrophage inflammatory protein (MIP-1α) upregulation. Methods THP-1 monocytes were incubated with HCY, with and without NF-κB inhibitor pyrolidine dithiocarbamate (PDTC) pretreatment. Northern blot analysis and flow cytometry were used to detect MIP-1α mRNA and protein respectively. The nuclear protein NF-κB P65 subunit and the inhibitory protein IκB-α were analyzed by Western blotting. Results Compared with controls, HCY, at a concentration of 0.1 mmol/L, was able to enhance the expression of MIP-1α mRNA (up to 3.69-fold) and protein (1.16-fold) in THP-1 monocytes, as well as enhance NF-κB P65 transcription to nuclear proteins. These actions were significantly suppressed after pretreatment with 100 μmol/L PDTC for 30 minutes before HCY incubation; whereas incubation of THP-1 monocytes with PDTC only had no effect on both the expression of MIP-1α and nuclear transcription of NF-κB P65. Moreover, the level of IκB-α protein in THP-1 monocytes decreased after a 30-minute incubation with HCY, which gradually increased after 120 minutes. Conclusions Homocysteine at a pathologic concentration stimulates MIP-1α expression in THP-1 monocytes, probably via NF-κB activation. Such activation may be caused by enhanced phosphorylation and degradation of the inhibitor protein IκB-α.

关 键 词：同型半胱氨酸 NF-ΚB活化 MIP-1Α IΚB-Α 表达 PDTC THP-1 RNA 核转位 蛋白磷酸化 

分 类 号：R543[医药卫生—心血管疾病]