Department of Integrative Physiology, University of Colorado, Boulder, USA.
Am J Hypertens. 2012 Oct;25(10):1050-4. doi: 10.1038/ajh.2012.70. Epub 2012 Jun 7.
We performed a pilot study to test the hypothesis that acute oral ingestion of tetrahydrobiopterin (BH(4)), a key cofactor modulating vascular nitric oxide (NO) synthase activity, improves large elastic artery stiffness with aging in men.
Healthy older (63 ± 2 years; n = 8) and young (age 25 ± 1 years; n = 6) men were studied 3 h after ingestion of BH(4) (10 mg·kg(-1) body weight) or placebo on separate days in a randomized, placebo-controlled, double-blind study.
Baseline carotid artery compliance was 37% lower (0.17 ± 0.02 vs. 0.22 ± 0.02 mm/mm Hg·10(-1)) and β-stiffness was 42% higher (7.3 ± 1.1 vs. 4.2 ± 0.5 AU) in the older men (both P < 0.05). BH(4) ingestion markedly increased circulating BH(4) concentrations in both groups (17-19-fold, P < 0.05), but increased compliance (+39% to 0.23 ± 0.02 mm/mm Hg·10(-1), P < 0.01) and decreased β-stiffness index (-27% to 5.3 ± 0.7 AU, P < 0.01) only in the older men. BH(4) also reduced carotid systolic blood pressure (SBP) in the older men (P < 0.05).
These preliminary results support the possibility that limited BH(4) bioavailability contributes to impaired carotid artery compliance in healthy older men. Further studies are needed to determine if increasing BH(4) bioavailability though oral BH(4) supplementation may have therapeutic efficacy for improving large elastic artery compliance and reducing central SBP with aging.
我们进行了一项初步研究，以检验以下假设，即急性口服四氢生物蝶呤（BH 4 ），一种调节血管一氧化氮合酶活性的关键辅助因子，可以改善男性随年龄增长导致的大动脉弹性硬度。
在一项随机、安慰剂对照、双盲研究中，分别于 3 小时后，在健康的老年男性（63 ± 2 岁，n = 8）和年轻男性（年龄 25 ± 1 岁，n = 6）中，测试了 BH 4 （10 mg·kg -1 体重）或安慰剂的口服摄入对颈动脉顺应性的影响。
老年男性的基础颈动脉顺应性低 37%（0.17 ± 0.02 比 0.22 ± 0.02 mm/mm Hg·10 -1 ），β 硬度高 42%（7.3 ± 1.1 比 4.2 ± 0.5 AU）（两者 P < 0.05）。BH 4 摄入使两组的循环 BH 4 浓度显著增加（17-19 倍，P < 0.05），但仅在老年男性中增加了顺应性（增加 39%，至 0.23 ± 0.02 mm/mm Hg·10 -1 ，P < 0.01）和降低了 β 硬度指数（减少 27%，至 5.3 ± 0.7 AU，P < 0.01）。BH 4 还降低了老年男性的颈动脉收缩压（SBP）（P < 0.05）。
这些初步结果支持这样一种可能性，即有限的 BH 4 生物利用度可能导致健康老年男性颈动脉顺应性受损。需要进一步研究来确定通过口服 BH 4 补充增加 BH 4 生物利用度是否可以改善大动脉弹性顺应性并随着年龄增长降低中心 SBP 从而具有治疗效果。
