Eldibany Mohamed M, Caprini Joseph A
Department of Pathology and Laboratory Medicine, Evanston Northwestern Healthcare, Northwestern University Feinberg School of Medicine, Evanston, IL 60201, USA.
Arch Pathol Lab Med. 2007 Jun;131(6):872-84. doi: 10.5858/2007-131-872-HATAO.
Homocysteine, a sulfur-containing amino acid, absent in natural diets, is a metabolic intermediary in transmethylation and transsulfuration reactions. Such reactions are essential to normal cellular growth, differentiation, and function. Excess homocysteine is associated with vascular disease and related disorders.
To review homocysteine metabolism, the pathogenesis and classification of hyperhomocysteinemia, and the published literature investigating the association of homocysteine and methylenetetrahydrofolate reductase defects with arterial and venous thromboembolism and related disorders. The role of vitamin supplementation in patients with hyperhomocysteinemia is addressed.
Published medical and scientific literature. Articles addressing the objectives were selected and reviewed. Pertinent studies and conclusions were summarized, grouped, and contrasted.
The association of hyperhomocysteinemia and arterial and venous thrombosis is controversial. Severe hyperhomocysteinemia is associated with atherosclerosis. The effect of mild hyperhomocysteinemia is less certain. Coinheritance of methylenetetrahydrofolate reductase defects and factor V Leiden is likely to increase the risk of venous thromboembolism. The association of methylenetetrahydrofolate reductase defects combined with no additional thrombophilic risk factors with venous thrombosis is less clear. High doses of folic acid to lower homocysteine levels might not be necessary.
同型半胱氨酸是一种含硫氨基酸，天然饮食中不存在，是转甲基化和转硫反应中的代谢中间体。此类反应对正常细胞生长、分化及功能至关重要。同型半胱氨酸过多与血管疾病及相关病症有关。
综述同型半胱氨酸代谢、高同型半胱氨酸血症的发病机制与分类，以及已发表的关于同型半胱氨酸和亚甲基四氢叶酸还原酶缺陷与动脉和静脉血栓栓塞及相关病症关联的文献。探讨维生素补充剂在高同型半胱氨酸血症患者中的作用。
已发表的医学和科学文献。选取并综述了涉及这些目标的文章。对相关研究及结论进行了总结、归类和对比。
高同型半胱氨酸血症与动脉和静脉血栓形成的关联存在争议。严重高同型半胱氨酸血症与动脉粥样硬化有关。轻度高同型半胱氨酸血症的影响尚不确定。亚甲基四氢叶酸还原酶缺陷与凝血因子V Leiden共同遗传可能会增加静脉血栓栓塞的风险。亚甲基四氢叶酸还原酶缺陷与无其他血栓形成风险因素共同存在与静脉血栓形成的关联尚不清楚。可能无需大剂量叶酸来降低同型半胱氨酸水平。
