脑梗死患者同型半胱氨酸、5,10-亚甲基四氢叶酸还原酶基因多态性与颈动脉粥样硬化的相关性

Relationship between homocysteine,polymorphism of methylenetetrahydrofolate reductase gene and carotid artherosclerosis in patients with cerebral infarction

目的探讨脑梗死患者急性期血清同型半胱氨酸（homocysteine,Hcy）、5,10-亚甲基四氢叶酸还原酶（methylenetetrahydrofolate,MTHFR）基因多态性与颈动脉粥样硬化之间的相关性。方法研究共纳入90例急性脑梗死患者和40例正常人,用循环酶法测定血清Hcy水平;用彩色多普勒超声检查颈动脉颅外段;采用聚合酶链反应-限制性内切酶片段长度多态性方法检测MTHFR基因型多态性。结果病例组颈总动脉（CCA）及颈内动脉（ICA）内中膜厚度（IMT）较对照组显著增厚（1.07±0.30）mm vs（0.87±0.33）mm,（1.00±0.31）mm vs（0.65±0.16）mm（均P〈0.01）。病例组较对照组颈动脉斑块发生率显著增高（74.4%vs 45.0%,P〈0.01）。病例组中不稳定斑块占所有斑块的比例较对照组中有增高的趋势,但差异无统计学意义（P〉0.05）。C/C、C/T、及T/T基因型人群血清Hcy水平分别为12.95（9.50~16.58）μoml/L,19.08（12.05~25.63）μoml/L,28.32（18.00~36.80）μoml/L,呈递增趋势,各组间差异有统计学意义（均P〈0.05）。Logistic回归分析显示在校正了传统的危险因素后,Hcy仍然是颈动脉粥样硬化的独立危险因素（P〈0.01）;MTHFRC677T基因多态性未进入回归方程。结论血清Hcy升高是脑梗死独立危险因素;MTHFRC677T基因多态性与颈动脉粥样硬化无相关性。

Objective To investigate the relationship of homocysteine（Hcy） level and genetic polymorphisms of methylenetetrahydrofolate reductase（MTHFR） C677T related to homocysteine metabolism with carotid artherosclerosis in acute cerebral infarction patients.Methods Serum Hcy levels of 90 cerebral infarction patients and 40 healthy people were measured by cyclophorase assay;carotid artherosclerosis was determined by use of the duplex ultrasonography;MTHFR genetic C677T polymorphism was determined by polymerase chain reaction and restriction digestion with Hinf I to distinguish mutant from wild-type alleles.Results The intima-media thickness（IMT） of common carotid artery（CCA） and internal carotid artery（ICA） in patients group was thicker than that in control group,（1.07±0.30） mm vs（0.87±0.33） mm and（1.00±0.31） mm vs（0.65±0.16）mm（both P〈0.01）.The incidence of carotid plaque in patients group was higher than that in control group（74.4% vs 45.0%,P〈0.01）.The ratio of unstable plaque was higher than that of stable plaque in patients group.The Hcy concentration in the population with TT genotype was significantly higher than in that with CC or CT genotype,12.95（9.50-16.58） μmol/L vs 19.08（12.05-25.63） μmol/L vs 28.32（18.00-36.80） μoml/L.Hcy was still an independent factor to carotid artherosclerosis after the correction of other traditional risk factors（P〈0.01）.MTHFR polymorphism did not enter into the regression equation.Conclusion Serum Hcy was an independent risk factor for the carotid artherosclerosis in cerebral infarction patients.Genetic mutations of MTHFRC677T did not show the correlation with carotid artherosclerosis.