高糖对人脐静脉内皮细胞TLR4表达的影响

Influence of high glucose to the expression of toll-like receptor 4 in human umbilical vein endothelial cells

目的观察高糖对人脐静脉内皮细胞TLR4表达的影响,比较加用脂多糖后不同浓度的高糖培养下对人脐静脉内皮细胞TLR4表达水平变化。方法将体外培养人脐静脉内皮细胞株分对照组(5mmol/LGS)、高糖组(10mmol/LGS、20mmol/LGS、40mmol/LGS)、高糖+LPS组(10mmol/LGS、20mmol/LGS、40mmol/LGS/+100ng/LLPS),培养24h后,用ELISA法检测各组上清IL-6水平,实时定量PCR检测各组细胞TLR4及MyD88基因表达水平。结果 (1)高糖培养能促使人脐静脉内皮细胞产生IL-6水平增加,具有统计学意义(P<0.05),在LPS诱导下高糖能进一步促进该细胞产生IL-6,具有统计学意义(P<0.05)。(2)随着葡萄糖浓度增高,从5mmol/L到20mmol/L,人脐静脉内皮细胞产生的IL-6逐渐增多,具有统计学意义(P<0.05),但再增高糖浓度(到40mmol/L),该细胞产生IL-6水平不再继续增加(P>0.05)。(3)在LPS存在的前提下,高糖能诱导人脐静脉内皮细胞TLR4和MyD88基因表达增加,具有统计学意义(P<0.05),但仅高糖培养对该细胞TLR4和MyD88基因表达无影响(P>0.05)。结论高糖能刺激人脐静脉内皮细胞炎症反应,使炎症因子IL-6产生增多,但对TLR4和MyD88表达无明显增高;而高糖联合LPS培养能诱导人脐静脉内皮细胞TLR4和MyD88表达上调,说明高糖在LPS存在前提下可能激发TLR4信号通路。

Objective To explore the influence on the expression of toll-like receptor 4（TLR4） in human umbilical vein endothelial cells（HUVEC） treated with high glucose,and to compare the different expression of TLR4 in HUVEC treated with different concentrations of glucose in the presence or absence of lipopolysaccharide（LPS）.Methods The HUVEC cultured in vitro were divided into groups as follows：normal control groups（5mmol/L GS）,groups cultured with different concentrations of high glucose（10mmol/L GS,20mmol/L GS,40mmol/L GS）and groups cocultured with high glucose and LPS（10mmol/L GS＋100ng/L LPS,20mmol/L GS＋100ng/L LPS,40mmol/L GS＋100ng/L LPS）.After cultured 24 hours,to detect the level of IL-6 in supernatant by ELISA,and the gene expression of TLR4 and MyD88 by real-time PCR of each group.Results（1）High glucose stimulates the production of IL-6 in HU VEC,and the effect goes further when cultured together with LPS（P0.05）.（2）The production of IL-6 is increasing when the glucose concentration upgrades from 5mmol/L to 20mmol/L（P〈0.05）,after then,upgrade the glucose such as to 40mmol/L,the production of IL6 does not increase further（P〈0.05）.（3）High glucose induces increase of the expression of TLR4 and MyD88 in HUVEC with the presence of LPS（P〉0.05）,however,only treated with high glucose makes no difference on the expression of TLR4 and MyD88（P〈0.05）.Conclusion High glucose can stimulate inflammatory reaction and increase the production of IL-6,but it makes no difference on the expression of TLR4 and MyD88,however the expression of TLR4 and MyD88 is up-regulated by together cocultured with high glucose and LPS.It shows that high concentration glucose may activated TLR4 signaling pathways on the basic of LPS.