高密度脂蛋白亚类抗脂多糖作用的研究

目的:探讨不同的高密度脂蛋白(HDL)亚类抗脂多糖(LPS)作用。方法:转染NF-κB-luc报告质粒至HepG2细胞,分析HDL各亚类对经LPS刺激的转染细胞荧光素酶表达的影响、HDL亚类与转染细胞孵育对LPS诱导的荧光素酶表达的影响以及HDL与LPS孵育对LPS诱导的荧光素酶表达的影响;运用逆转录-多聚酶链反应(RT-PCR)技术,分析HDL亚类与LPS孵育对LPS诱导的TNF-α mRNA表达的影响。结果:大颗粒HDL2孵育的细胞荧光素酶表达显著受到抑制;HDL3孵育的细胞荧光素酶表达略有降低;preβ1-HDL孵育的细胞荧光素酶表达未见改变;LPS-HDL2复合物刺激的细胞荧光素酶表达显著受到抑制;LPS-HDL2复合物刺激的细胞TNF-α mRNA的表达也显著降低。结论:成熟的大颗粒HDL2能够显著抑制LPS诱导的荧光素酶活性以及TNF-α mRNA的表达,表明HDL2具有较强的结合和中和LPS的能力。

Study on the protective effect of HDL subclasses against lipopolysaccharide

AIM: To elucidate the anti-LPS effect of high-density lipoprotein (HDL) subclasses. METHODS: The pNF-kappaB-luc plasmid was transfected into HepG2 cells and the luciferase expression was obtained by the optimization of cell density, incubation time of transfected cells and stimulating concentration of LPS. The luciferase expression was examined in the cells treated with various stimulus including LPS, mixtures of HDL subclasses and LPS. The expression of TNF-alpha mRNA was detected RT-PCR. RESULTS: After LPS stimulation, HDL subclasses did not show obvious influence on the effect of LPS to stimulate the luciferase production. However, pre-incubation of cells or pre-incubation of LPS with large-sized HDL(2) strongly inhibited the effect of LPS to stimulate the luciferase production. When LPS was incubated with increased concentration of HDL(2), the LPS effect was decreased to a greater extent. Pre-incubation of LPS with HDL(2) before addition to the cells resulted in a significant decrease in the mRNA level of TNF-alpha. CONCLUSION: The largest HDL(2) has strong LPS-binding capacity and can inhibit the LPS induced TNF-alpha release in HepG2 cells; HDL(3) shows weak anti-LPS effect; small-sized prebeta(1)-HDL does not show anti-LPS effect.