摘要
目的研究不同浓度抵抗素对动脉粥样硬化形成过程中巨噬细胞脂质吞噬功能的影响。方法利用荧光定量聚合酶链反应(PCR)检测氧化型低密度脂蛋白(ox-DDL)对原代巨噬细胞抵抗素mRNA表达的影响。尼罗红染色观察抵抗素对THP-1分化的巨噬细胞脂质含量的影响。同时采用荧光定量PCR检测清道夫受体A型(SRA)、CD36 mRNA表达的变化;Western blot及流式细胞仪检测相关蛋白表达。结果ox-LDL明显促进巨噬细胞中抵抗素mRNA表达,4 h达到高峰,表达量约为非氧化LDL(nLDL)处理组的4倍(P< 0．001)。100 ng／mL抵抗素可使巨噬细胞内脂质荧光染色强度显著增加,表明促使脂质成分的吞噬。同时,抵抗素以时间和剂量依赖性在mRNA及蛋白水平促进清道夫Ⅱ型受体CD36和TLR4的表达,面对清道夫Ⅰ型受体SRA的表达无显著影响。结论ox-LDL诱导巨噬细胞表达抵抗素;后者通过上调清道夫受体CD36的表达,促进巨噬细胞吞噬脂质颗粒,从而增加其胞内脂质含量,在泡沫细胞形成中发挥作用。
Objective To study the influence of different concentrations of resistin on macrophagic lipid phagocytic function during atherosclerosis process. Mathods By using fluorescent quantitative polymerase chain reaction, we examined the mRNA level of resistin in the monocyte-derived macrophages（MDMs） that were treated with ox-LDL. Monocyte cell line THP-1 was selected for analyzing the changes of cholesterol ester by staining with Nile red, a vital dye specific for intracellular lipid droplets, when the THP-1-derived macrophages（THP-1 M） was treated with resistin. Real-time PCR, Western blot and flow cytometry were also used to reveal the expression patterns of SRA, CD36 in mRNA and protein levels for resistin-treated THP-1 M. Results It was found that ox-LDL at concentration 50 μg/mL was able to up-regulate gene expression of resistin in MDM and reached its peak level on 4 h, given a 4-fold expression as compared with that in the control treated with non-oxidized LDL（nLDL）. However, the Nile red staining showed that exogenous resistin at 100 ng/mL increased significantly the fluorescence intensity of lipid in THP-1 M cells. Resistin also promoted expressions of CD36, a type 2 scavenger receptor, in a timeand dose-dependent manner but not for expression of type 1 scavenger receptor SRA. Conclusion The expression of resistin in MDM could be promoted by stimulating with ox-LDL. Exogenous resistin is able to up-regulate CD36 expression at mRNA and protein levels, and to increase the lipid phagocytic power of macrophages resulting in lipids accumulation and formation of foam cells which seems to be related to the initiation and progression of atherosclerosis. （Shanghai Med J, 2006, 29：702-707）
出处
《上海医学》
CAS
CSCD
北大核心
2006年第10期702-707,F0003,共7页
Shanghai Medical Journal
