同型半胱氨酸致动脉粥样硬化的机制研究

目的通过观察不同浓度同型半胱氨酸(Homocysteine,Hcy)干预对人脐静脉血管内皮细胞(HumanUmbilical Vein Endothelial Cells,HUVEC)和氧化应激的影响,探讨其在动脉粥样硬化(Atherosclerosis,AS)中的作用。方法体外培养HUVEC,将其分为正常对照组(Hcy 0μmol·L-1)、Hcy干预组(浓度分别为50、100、200、500μmol·L-1)、100μM Hcy+叶酸+VitB12治疗组,每个浓度组再分为24、48、72h三个时间组。MTT法检测各组细胞增殖抑制率,测定各浓度Hcy干预HUVEC 72h的氧化应激损伤指标。结果各浓度Hcy干预组随着Hcy浓度增高及干预时间延长HUVEC的细胞增殖抑制率增加,500μM Hcy 72h干预组最明显(P<0.05)。HUVEC内H2O2和MDA含量随Hcy浓度的增加而增加,Hcy100～500μM组与对照组比较差异均有统计学意义(P<0.01);Hcy100～500μM组HUVEC内SOD活性和T-AOC活性均较对照组降低(P<0.01),并且Hcy的浓度越高降低程度越明显。100μM Hcy+叶酸+VitB12治疗组与对照组比较上述各指标的差异均无统计学意义(P>0.05)。结论 Hcy抑制HUVEC增殖的作用呈剂量依赖关系,病理水平Hcy可以增强氧化应激损伤反应,而叶酸和VitB12对Hcy所致氧化应激损伤有一定的拮抗作用。

Induced Hyperhommocysteinemia in the Study of the Mechanisms of Otherosclerosis

Objective To observe the effects of different concentrations of homocysteine(Homocysteine,Hcy) intervention on human umbilical vein endothelial cells(Human umbilical vein endothelial cells,HUVEC) and the effect of oxidative stress,and to explore its mechanisms in atherosclerosis(Atherosclerosis,AS) in rats.Methods HUVEC were cultured in vitro,which could be divided into the normal control group(Hcy 0μmol·L-1),Hcy group(concentrations were 50,100,200,500 μmol·L-1),100 μM Hcy+VitB12 of folic acid treatment group.The concentration of each group was further divided into 24h,48h,72h group.Cell proliferation inhibition was detected by MTT.Results HUVEC cell proliferation inhibition rate increased,500 μM Hcy 72h group was the most(P<0.05) while the concentration of Hcy group with the Hcy concentration increased and intervention time prolonged.HUVEC H2O2 and MDA content increased as the concentration of Hcy increased(P<0.01);Hcy100 ~ 500μM group HUVEC SOD activity and T-AOC activity were lower than those in control group(P<0.01).100 μM Hcy+ VitB12 of folic acid treatment group compared with the control group the differences of each index were not statistically significant(P>0.05).Conclusion The Hcy inhibit HUVEC proliferation showed a dose dependent relationship.Pathological levels of Hcy could enhance oxidative stress response to injury.Folic acid and VitB12 has certain antagonism against Hcy induced oxidative stress injury.