脂多糖对肠黏膜微血管内皮细胞表达TLR2和TLR4的影响

Effect of Lipopolysaccharide on the Expression of TLR2 and TLR4 in Intestinal Mucosa Microvascular Endothelial Cells

为研究TLR2、TLR4在脂多糖(lipopolysaccharide,LPS)致肠黏膜微血管内皮细胞(RIMECs)损伤中的作用,以体外培养的肠黏膜微血管内皮细胞为模型,用浓度为1、5、10μg/m L的LPS刺激RIMECs3、6、9、12、24 h后,采用半定量RT-PCR法检测细胞表面TLR2和TLR4的表达情况;再以浓度为1、5、10μg/m L的LPS刺激RIMECs 9 h后,半定量RT-PCR法检测细胞TLR2和TLR4的表达情况。结果发现:与对照组比较,不同浓度LPS刺激均能引起RIMECs表面TLR2和TLR4 m RNA表达增加。不同浓度LPS刺激不同时间后,RIMECs表面TLR2和TLR4 m RNA表达基本均在9 h达到峰值,且无时间依赖性。用LPS刺激RIMECs 9 h,5μg/m L的LPS对细胞表达TLR2 m RNA作用最强且无剂量依赖性,10μg/m L LPS对细胞表达TLR4 m RNA作用最强且呈剂量依赖性。TLR2和TLR4在LPS损伤RIMECs的过程中起到重要作用。

The aim of the study was to investigate the role of TLR2, TLR4 in injury of rat intestinal mucosamicrovascular endothelial cells（RIMECs） induced by lipopolysaccharide（LPS）. Rat intestinal mucosamicrovascular endothelial cell in vitro was taken as a model, and different concentrations of LPS（1, 5, 10 μg/m L）were used to stimulate RIMECs for different times（3, 6, 9, 12, 24 h）. Expressions of TLR2 and TLR4 on cellsurface were detected by semi quantitative RT-PCR method. LPS at different concentrations（1, 5, 10 g/m L）were used to stimulate RIMECs for 9 h. Then expressions of TLR2 and TLR4 cells were detected by semiquantitative RT-PCR method. The results showed that expression of TLR2 and TLR4 increased when RIMECswere stimulated by LPS compared with the control group. Moreover, after stimulation with differentconcentrations of LPS for different times, expression of TLR2 m RNA and TLR4 m RNA basically reached thepeak at 9 h, and the expression was time-independent. Expression of TLR2 m RNA was the highest when theconcentration of LPS was 5 μg/m L after 9 h, and the expression was dose-independent. LPS at a concentrationof 10 μg/m L stimulating RIMECs had the strongest effect in the expression of TLR4 m RNA, and was dosedependent. The results demonstrated that TLR2 and TLR4 played an important role in the process of LPSdamaging RIMECs.