氧化低密度脂蛋白对血管平滑肌细胞TLR4和Emilinl表达的影响

目的 观察氧化低密度脂蛋白(ox-LDL)对大鼠血管平滑肌细胞(VSMCs)TLR4和Emilinl表达的影响及转化生长因子-β(TGF-β)在其中所起的作用.方法 将传至2～4代的大鼠VSMCs,用不同浓度的OX-LDL(20、50、80、100μg/ml)干预,采用RT-PCR检测TLR4和Emilinl mRNA表达变化.另设100μg/ml ox-LDL+TGF-B(0.01、0.1、1、10μg/1)培养24h,采用RT-PCR检测TLR4 mRNA表达.结果 (1)用四种不同浓度梯度的ox-LDL作用后的VSMCs,TLR4和Emilinl在mRNA水平均比空白对照组表达增加,并且呈浓度依赖性.(2)不同浓度TGF-B(0.01、0.1、1、10μg/1)作用后的ox-LDL组(100μg/ml)TLR4 mRNA表达明显下降,且呈浓度依赖性.结论 ox-LDL可诱导大鼠VSMCs TLR4和Emilinl的表达,促进炎症的发展,ox-LDL可通过使VSMCs Emilinl表达增高途径抑制TGF-β的表达,最终达到促进TLR4高表达的目的 .ox-LDL对TGF-β的抑制作用是上调VSMCs TLR4表达的重要途径之一.

Effects of oxidized-low density lipoprotein on expressions of Toll-like receptor 4 and Emilinl in vascular smooth muscle cells

Objective To examine the effects of oxidized -low density lipoprotein (ox - LDL) and transforming growth factor - on expressions of Toll -like receptor 4(TLR4) and Emiinl in cultured rat vascular smith muscle cells (VSMCs). Methods Rat VSMCs were incubated with different concentrations of ox - LDL(20,50,80,100μg/ml) ,TLR4 and Emilinl mRNA expressions were detected by RT-PCR. The second group was incubated with different concentrtions of TGF - βSand ox - LDL(100μg/ml). Results The mRNA expressions of TLR4 and Emilinl were concentration - dependently increased "after VSMCs were stimulated by diferent concentrations of ox - LDL for 24h ,and the mRNA expressions of TLR4 were concentration - dependently decreased after VSMCs were stimulated by diferent concentrations of TGF -βand ox - LDL(100μg/ml) for 24h. Conclusions Ox - LDL could increase the expression activities of TLR4 and Emilinl promotes the inflanmmtory progress. It decreases the TGFβexpression,then up -regulates the expression of TLR4 by increasing the expression of Emilinl, which is a main path for un - regulating VSMCs TLR4's expression.