维生素E和β胡萝卜素对巨噬细胞氧化修饰低密度脂蛋白的影响

EFFECTS OF α-TOCOPHEROL AND β-CAROTENE ON OXIDATION OF LOW DENSITY LIPOPROTEIN BY MONOCYTE DERIVED MACROPHAGES

目的 : 研究维生素 E(VE)、β胡萝卜素 (βC)对巨噬细胞 (MΦ )介导的低密度脂蛋白 (LDL)氧化修饰能力的影响。方法 : 于培养成熟的 MΦ中分别加入不同剂量的 VE(40、1 0 0、2 0 0 μmol/L)和 βC(0 .5、1 .0、2 .0 μmol/L) 37℃孵育 2 4 h,通过测定培养物上清液中硫代巴比妥酸反应物 (TBARS)、荧光物质 (Lipofusin)、LDL电泳迁移率 (Rf)及共轭二烯 (Dienes)的形成 ,反映LDL的氧化修饰程度。结果 : 体外补充 VE可以显著降低培养物上清液中 TBARS、荧光物质以及共轭二烯的形成 ,明显抑制 LDL的电泳迁移率 ,随剂量增大作用加强 ;βC低剂量组 (0 .5μmol/L)可显著降低培养物上清液中 TBARS、荧光物质以及共轭二烯的形成 ,明显抑制 LDL的电泳迁移率 ,其余各组无明显影响。结论 : VE、βC均可抑制 MΦ介导 LDL氧化修饰的能力 ,并具一定的量效关系 ,提示在 MΦ氧化修饰 LDL的可调节因子中 。

Objective: To examine the effects of β carotene and α tocopherol on LDL oxidation by monocyte derived macrophages from SD rats (in DMEM medium). [WT5FZ]Methods: Macrophages were incubated with LDL in DMEM in which freshly dissoved VE (40,100,200 μmol/L) and βC (0.5,1.0,2.0 μmol/L) had been added. After incubating for 24 h, the mediums were centrifuged to determine TBARS and lipofusin and dienes. [WT5FZ]Results: Supplementation of α tocopherol significantly decreased TBARS, lipofusin and conjugated dienes production and electrophoretic mobility. Supplementation of β carotene at 0.5 μmol/L significantly decreased TBARS, lipofusin and conjugated dienes production and electrophoretic mobility, but other levels showed no effect. Increasing β carotene concentration to 2.0 μmol/L in the system increased the lipofusin production compared with control group. α tocopherol at 200 μmol/L and β carotene at 0.5 μmol/L were the most effective in all dose groups. [WT5FZ]Conclusion: Cell mediated oxidation of LDL can be regulated by antioxidants such as α tocopherol and β carotene.