Fridman Osvaldo, Porcile Rafael, Vanasco Virginia, Junco Mariano N, Gariglio Luis, Potenzoni Miguel A, Bañes Isabel, Morales Analía
Centro de Altos Estudio en Ciencias de la Salud, Universidad Abierta Interamericana (UAI), Ciudad Autónoma de Buenos Aires, Argentina.
Clin Exp Hypertens. 2008 Oct;30(7):574-84. doi: 10.1080/10641960802251958.
The substitution of cytosine (C) by thymine (T) at nucleotide 677 of the methylenetetrahydrofolate reductase (MTHFR) gene, which converts an alanine to a valine residue, is a frequent polymorphism with reduced specific activity, associated with moderate increase in plasma homocysteine levels (tHcy) and risk of vascular diseases.
This study was designed to investigate an association of this polymorphism with tHcy and vascular risk factors.
We used a cross-sectional study on subjects affiliated to three health centers from Buenos Aires city. The diagnosis of hypertension was ascertained by patients' clinical history. Only subjects under long-term antihypertensive treatment were included.
Samples from 138 physically active individuals (44 men and 94 women) randomly selected were included. The mean tHcy was significantly higher amongst hypertensives (HT) than normotensives (NT). The risk of hypertension was compared in subjects with CC genotype and the combined number of subjects with at least one T allele (CT/TT). There was no significant difference regarding the risk of hypertension between NT and HT groups in the overall sample. However, as obesity is considered a risk factor for hypertension development, when only HT (n = 29) and NT (n = 66) subjects with body mass index below 30 kg/m(2) (BMI<30) were compared, subjects bearing CT/TT presented a significantly higher risk of hypertension than those bearing the CC genotype and significantly higher concentration of tHcy.
Our results indicate an association of hyper-tHcy and MTHFR C677T mutation with hypertension. MTHFR C677T mutation may contribute to hypertension or affect the development of hypertension through hyperhomocysteinemia.
亚甲基四氢叶酸还原酶（MTHFR）基因第677位核苷酸处胞嘧啶（C）被胸腺嘧啶（T）取代，导致丙氨酸残基转变为缬氨酸残基，这是一种常见的多态性，其特定活性降低，与血浆同型半胱氨酸水平（tHcy）适度升高及血管疾病风险相关。
本研究旨在调查这种多态性与tHcy及血管危险因素之间的关联。
我们对来自布宜诺斯艾利斯市三个健康中心的受试者进行了横断面研究。高血压的诊断通过患者的临床病史确定。仅纳入长期接受抗高血压治疗的受试者。
纳入了随机选择的138名身体活跃个体（44名男性和94名女性）的样本。高血压患者（HT）的平均tHcy显著高于血压正常者（NT）。比较了CC基因型受试者与至少携带一个T等位基因（CT/TT）的受试者组合发生高血压的风险。在整个样本中，NT组和HT组之间高血压风险没有显著差异。然而，由于肥胖被认为是高血压发生的危险因素，当仅比较体重指数低于30 kg/m²（BMI<30）的HT受试者（n = 29）和NT受试者（n = 66）时，携带CT/TT的受试者发生高血压的风险显著高于携带CC基因型的受试者，且tHcy浓度显著更高。
我们的结果表明高tHcy和MTHFR C677T突变与高血压有关。MTHFR C677T突变可能通过高同型半胱氨酸血症导致高血压或影响高血压的发展。
