维生素E对氧化低密度脂蛋白诱导的单核细胞/内皮细胞粘附的干预作用

Effect of vitamin E on ox-LDL-induced monocyte/endothelium adhesion

目的 :观察ox-LDL在体外对兔单核细胞与血管内皮细胞粘附的影响及维生素E的干预作用 ,初步探讨其机制。方法 :培养兔主动脉内皮细胞。密度梯度离心法分离健康兔单核细胞。沉淀法制备人LDL ,硫酸铜氧化制备ox-LDL。用Kim等[1] 方法并略加改良观察ox -LDL对内皮细胞 /单核细胞粘附的影响及维生素E的干预。Northernblot检测内皮细胞VCAM - 1mRNA的表达。结果 :ox -LDL浓度为 2 5mg/L、5mg/L、10mg/L时 ,每个视野粘附的单核细胞数分别为 132 8± 2 0 2、35 0 0± 37 2、5 0 2 6± 78 8,而正常对照组为 5 1 2± 7 7,相差非常显著 (P <0 0 1)。在加ox -LDL( 10mg/L)前加维生素E干预 ,当维生素E浓度为 10 μmol/L、2 0 μmol/L、4 0 μmol/L时 ,粘附单核细胞数分别为 4 2 2 3± 32 2、2 98 0± 2 1 7、2 0 5 2± 36 6 ,均低于ox -LDL对照组的 5 0 2 6± 78 8,维生素E浓度为 10μmol/L组与对照组相差不显著 (P >0 0 5 ) ,其余两组与ox-LDL对照组相差非常显著 (P <0 0 1)。ox -LDL对照组内皮细胞VCAM - 1mRNA表达高于维生素E( 4 0 μmol/L)干预组 ( 0 4 9± 0 0 9vs 0 33± 0 10 ,P <0 0 5 )。 结论 :ox -LDL促进兔主动脉内皮细胞与单核细胞的粘附 ,其机制与其促进内皮细胞表达VCAM - 1有关。?

AIM: To observe the role of ox-LDL in rabbit endothelium/circulating monocyte adhesion in vitro and the effect of vitamin E. METHODS: Cultured rabbit's endothelial cells were incubated with different concentrations of ox-LDL, then incubated with rabbit's monocytes to observe cell's adhesion. With Northern blotting, endothelial VCAM-1 mRNA expression was measured. By using vitamin E incubation before ox-LDL, above steps were repeated to observe the effect of vitamin E. RESULTS: When ox-LDL concentrations were 2 5 mg/L, 5 mg/L, 10 mg/L, monocytes adhesive to endothelium per microscope field were 132 8±20 2, 350 0±37 2, 502 6±78 8, respectively They were all significantly higher than that of control group (51 2±7 7, P< 0 01) Addition of vitamin E at comcentration of 10 μmol/L, 20 μmol/L, 40 μmol/L respectively before ox-LDL incubation yield fewer adhesive monocytes as follow: 422 3±32 2, 296 0±21 7, 205 2±36 6, respectively, but only the last two concentrations had significant effects ( P< 0 01) Endothelial VCAM-1 mRNA expression in ox-LDL group was higher than that in vitamin E group (0 49±0 09 vs 0 33±0 10, P< 0 05) CONCLUSIONS: ox-LDL directly enhances rabbit's endothelium/monocyte adhesion by inducing expression of VCAM-1 in endothelium. Vitamin E inhibites these effects of ox-LDL.