Folic acid improves endothelial function in coronary artery disease via mechanisms largely independent of homocysteine lowering
Folic acid improves endothelial function in coronary artery disease via mechanisms largely independent of homocysteine lowering
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DOI：
10.1161/hc0102.101388
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发表时间：
2002-01-01
期刊：
影响因子：
37.8
通讯作者：
Goodfellow, J
中科院分区：
文献类型：
--
作者：
Doshi, SN;McDowell, IFW;Goodfellow, J
背景-同型半胱氨酸是冠状动脉疾病(CAD)的危险因素，尽管因果关系仍有待证实。确定直接因果关系的重要性在于这样一个事实，即用叶酸可以安全且廉价地将血浆同型半胱氨酸降低25%。这种减少最大的剂量是0.4 mg/d。大剂量叶酸(5 mg/d)可以改善冠心病的内皮功能，尽管其机制存在争议。已经提出通过减少总同型半胱氨酸(THcy)或游离(非蛋白结合)同型半胱氨酸(FHcy)来改善病情。在冠心病患者同型半胱氨酸改变之前，我们研究了叶酸对血管内皮功能的影响。方法和结果：33例患者进行了为期6周的随机、安慰剂对照研究。于用药前、用药后2小时、4小时及用药6周后，用血流介导的扩张法测定血管内皮功能。血浆叶酸在1小时后显著升高(200与25.8nmol/L比较；P
Background-Homocysteine is a risk factor for coronary artery disease (CAD), although a causal relation remains to be proven. The importance of determining direct causality rests in the fact that plasma homocysteine can be safely and inexpensively reduced by 25% with folic acid. This reduction is maximally achieved by doses of 0.4 mg/d. High-dose folic acid (5 mg/d) improves endothelial function in CAD, although the mechanism is controversial. It has been proposed that improvement occurs through reduction in total (tHcy) or free (non-protein bound) homocysteine (fHcy). We investigated the effects of folic acid on endothelial function before a change in homocysteine in patients with CAD.Methods and Results-A randomized, placebo-controlled study of folic acid (5 mg/d) for 6 weeks was undertaken in 33 patients. Endothelial function, assessed by flow-mediated dilatation (FMD), was measured before, at 2 and 4 hours after the first dose of folic acid, and after 6 weeks of treatment. Plasma folate increased markedly by 1 hour (200 compared with 25.8 nmol/L; P