Department of Internal Medicine, University of Maryland Medical Center, 22 S Greene St, N3E09, Baltimore, MD, MD 21201, USA; Division of Cardiovascular Medicine, Department of Medicine, University of Maryland School of Medicine, 110 S Paca St, Suite 7-124, Baltimore, MD 21201, USA.
Department of Internal Medicine, University of Maryland Medical Center, 22 S Greene St, N3E09, Baltimore, MD, MD 21201, USA; Division of Cardiovascular Medicine, Department of Medicine, University of Maryland School of Medicine, 110 S Paca St, Suite 7-124, Baltimore, MD 21201, USA; Department of Epidemiology and Public Health, University of Maryland School of Medicine, Baltimore, MD, USA.
Nutr Metab Cardiovasc Dis. 2019 May;29(5):513-517. doi: 10.1016/j.numecd.2019.02.003. Epub 2019 Feb 22.
Dietary nutrient intake and its metabolism by the gut microbiome have recently been implicated in cardiovascular disease (CVD) risk. In particular, trimethylamine N-oxide (TMAO), a metabolite of the gut microbiota, has been shown to be a predictor of incident CVD events. Elevated levels of branched-chain amino acids (BCAA) have also been associated with an increased propensity for insulin resistance.
To study the association of dietary intake with systemic TMAO, its nutrient precursors, and BCAA levels on fasting plasma levels of TMAO and its nutrient precursors and BCAA, we conducted an exploratory post-hoc analysis of 3 popular diets - high fat (Atkins), Mediterranean (South Beach), and very low fat (Ornish) - using plasma samples from a prior randomized, crossover study, with each isocaloric dietary phase lasting 4 weeks. Metabolites were quantified using stable isotope dilution HPLC with on-line tandem mass spectrometry.
Compared to the low fat Ornish phase, the high fat Atkins dietary phase was characterized by increased levels of TMAO (3.3 vs. 1.8 μM, p = 0.01), and the BCAA valine (272.8 vs. 235.8 μM, p = 0.005) and leucine (105.9 vs. 96.4 μM, p = 0.01). The high fat Atkins dietary phase was also associated with higher levels of TMAO (3.3 vs 1.6 μM, p = 0.04), valine (272.8 vs. 240.7 μM, p = 0.004), and leucine (105.9 vs. 96.4 μM, p = 0.01) compared to baseline.
These data suggest that over a 4-week interval, a saturated fat diet that is predominantly animal-based, compared to an isocaloric, low fat, predominantly plant-based diet, is associated with heightened risk for cardiometabolic derangements, as monitored by a higher plasma levels of both TMAO and BCAA.
膳食营养素的摄入及其在肠道微生物群中的代谢最近与心血管疾病 (CVD) 风险有关。特别是，肠道微生物群的代谢产物三甲胺 N-氧化物 (TMAO) 已被证明是 CVD 事件的预测因子。支链氨基酸 (BCAA) 水平升高也与胰岛素抵抗的易感性增加有关。
为了研究饮食摄入与系统 TMAO、其营养前体和 BCAA 水平与空腹血浆 TMAO 及其营养前体和 BCAA 水平之间的关系，我们对三种流行的饮食方式（高脂肪（阿特金斯）、地中海（南滩）和极低脂肪（奥尼什））进行了探索性事后分析，使用来自先前随机交叉研究的血浆样本，每个等热量饮食阶段持续 4 周。使用稳定同位素稀释 HPLC 结合在线串联质谱法定量代谢物。
与低脂肪的奥尼什饮食阶段相比，高脂肪的阿特金斯饮食阶段的 TMAO 水平升高（3.3 与 1.8 μM，p = 0.01），BCAA 缬氨酸（272.8 与 235.8 μM，p = 0.005）和亮氨酸（105.9 与 96.4 μM，p = 0.01）。高脂肪的阿特金斯饮食阶段也与 TMAO（3.3 与 1.6 μM，p = 0.04）、缬氨酸（272.8 与 240.7 μM，p = 0.004）和亮氨酸（105.9 与 96.4 μM，p = 0.01）水平升高相关。
这些数据表明，在 4 周的时间内，与等热量、低脂肪、主要以植物为基础的饮食相比，以饱和脂肪为主的动物饮食与心脏代谢紊乱的风险增加有关，这可以通过更高的血浆 TMAO 和 BCAA 水平来监测。
