不饱和脂肪酸影响HepG-2细胞PAI-1表达的机制初探  

Mechanism of unsaturated fatty acids influencing plasminogen activator inhibitor-1 expression in HepG-2 cells

作　　者：贺艳丽[1] 叶平[2] 周新[3] 方红[3] 王琼[4] 刘永学[4] 

机构地区：[1]华中科技大学协和医院干细胞研究中心,湖北武汉430022 [2]解放军总医院老年心内科,北京100853 [3]武汉大学中南医院基因诊断中心,湖北武汉430071 [4]北京放射医学研究所药理毒理室,北京100850

出　　处：《中国病理生理杂志》2005年第3期436-440,共5页Chinese Journal of Pathophysiology

基　　金：国家自然科学基金资助项目 (No .39970 30 1)

摘　　要：目的 :探讨不饱和脂肪酸对HepG - 2细胞纤溶酶原激活物抑制剂 - 1(PAI- 1)表达的影响及其机制。方法 :以发色底物法检测PAI- 1活性 ,RT -PCR法检测PAI- 1mRNA水平 ;构建两个含不同片段缺失的PAI- 1启动子序列控制表达的氯霉素转移乙酰酶 (CAT)报告基因质粒 ,转染HepG - 2细胞 ,ELISA法检测CAT表达量。结果 :油酸、亚油酸诱导下HepG - 2细胞PAI- 1mRNA表达及蛋白活性显著高于对照组 ;共转染过氧化体增殖物激活型受体表达质粒 (PPARα -pSG5 )PAI- 1转录活性显著增加 ;转染NF -κB样蛋白结合序列缺失的重组质粒 ,亚油酸诱导下PAI- 1转录活性显著增加 ,而转染VLDL/脂肪酸反应元件缺失的重组质粒则无显著变化。结论 :不饱和脂肪酸增强HepG - 2细胞PAI- 1mRNA表达及活性 ;PPARα可能是其上调PAI- 1表达所涉及的转录因子之一 ,且VLDL/脂肪酸反应元件在该调控中具有重要作用 ,但可能并不涉及NF -κB信号转导途径。AIM: To investigate the influence and mechanisms of unsaturated fatty acid on PAI-1 expression in HepG-2 cells. METHODS: PAI-1 activity and mRNA expression were determined by colorimetric assay and RT-PCR, respectively. Two types of CAT reporter gene plasmid containing different deletions in PAI-1 promoter were constructed and transfected into HepG-2 cells, respectively. The transcriptional activity of PAI-1 was demonstrated by the CAT's expression. RESULTS: The mRNA and activity of PAI-1 significantly increased in the groups of oleic acid and linoleic acid compared with the control. When co-transfected with PPARα-pSG5, the level of PAI-1 transcription was significantly increased. In the HepG-2 cells transfected with NF-κB-like sequence-deletion-pCAT construct linoleic acid, the PAI-1 transcriptional activity increased, and no significant change was observed when transfected with VLDL/fatty acid response element-deletion-pCAT construct. CONCLUSIONS: Unsaturated fatty acids induce PAI-1 activity and mRNA expression in HepG-2 cells. PPARα may be one of transcription factors playing a role in the regulation of PAI-1 gene expression. The VLDL/fatty acid response element in the PAI-1 promoter may play an important role in the regulation, but not the NF-κB-like sequence.

关 键 词：脂肪酸类 不饱和 纤溶酶原激活物抑制物1 HEPG-2细胞 

分 类 号：R363[医药卫生—病理学]