同型半胱氨酸及其代谢酶基因多态性与脑梗死相关性研究进展

摘要

同型半胱氨酸(Hcy)是细胞内蛋氨酸代谢产生的一种含硫基的氨基酸,存在于人体多数组织内,多种原因均可导致 Hcy 在体内蓄积。 Hcy 是动脉粥样硬化的危险因素之一,且与脑梗死的发病密切相关。 Hcy 代谢的关键酶如5,10-亚甲基四氢叶酸还原酶(MTHFR)和蛋氨酸合酶(MS)、胱硫醚合成酶(CBS)以及蛋氨酸合成酶还原酶(MSR)等的突变及多态性均可导致 Hcy 水平的变化,进而影响脑梗死的发生。 MTHFR 和 CBS 基因错义突变是引起其酶缺乏或活性降低的主要机制,常见的突变位点有 MTHFR C677T、A1298C,CBS T833C、G919A、844ins68等。目前国内外关于 Hcy 及其代谢酶基因多态性与脑梗死的相关性仍存在争议,还需要更多、更深入的研究。%Hyperhomocysteine(Hcy) produced by methionine metabolism is a kind of amino acids containing sulfhydryl group,which exists in the most human body tissues. Many reasons can cause Hcy accumulation in body. Hcy has been proved to be one of the independent risk factors for atherosclerosis,closely associated with the progression of stroke. The key enzymes of gene mutation and polymorphism of Hcy metabolisms such as methylenete-trahydrofolate reductase gene(MTH-FR),methionine synthetase(MS),cystathionine β-synthase gene(CBS) and methionine synthase reductase(MSR) can lead to Hcy levels change,and influence the occurrence of stroke. The missense mutation of MTHFR and CBS gene are the main mechanisms of the enzyme deficiency or reduced activity,and the common mutations are MTHFR C677T,A1298C and CBS T833C,G919A and 844ins68. Now the correlation of enzyme gene polymorphism and cerebral infarction is still controversial and needs further studies both at home and abroad.