Department of Chemical Pathology, National Health Laboratory Service and Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa.
Medical Research Council/Wits Developmental Pathways for Health Research Unit, Department of Paediatrics, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa.
Metabolomics. 2020 Oct 8;16(10):108. doi: 10.1007/s11306-020-01734-7.
Studies have shown that systemic levels of branched-chain amino acids (BCAAs) and aromatic amino acids (AAAs) are elevated in cardiometabolic diseases (CMDs) in populations resident in high income countries. However, little is known about the association of BCAAs and AAAs with metabolic syndrome and its components in Asian Indian (AI) and Black African (BA) populations.
The aim of this study was to describe the association of BCAAs and AAAs with the metabolic syndrome, its individual components and insulin resistance in AI and BA populations.
Serum samples collected from AI (n = 349) and BA (n = 369) subjects were used to measure levels of BCAAs and AAAs by ultra-pressure liquid chromatography tandem mass spectrometry (UPLC-MS/MS). Anthropometric, demographic and cardiometabolic variables were measured in all subjects.
The sum of BCAAs and AAAs was higher in AIs compared to BAs. The BCAAs and AAAs were positively associated with insulin resistance, metabolic syndrome and its individual components. This was particularly the case for AI subjects, in unadjusted regression models. However, these associations were non-significant after adjusting for co-variates, particularly visceral adipose tissue (VAT). Triglyceride levels were significantly associated with valine and leucine levels in BAs even after adjustment for co-variates. Lastly, we found that fasting circulatory BCAA and AAA levels are strongly correlated with VAT in both populations.
This study identified specific associations of serum valine and leucine levels with triglycerides in BAs. The association of amino acids with CMDs was observed in AIs, but was found to be the result of confounding by VAT. Further studies are required to determine whether BCAAs and AAAs are aetiological factors in CMDs and how VAT modulates their serum levels.
研究表明，在高收入国家的居民中，患有心血管代谢疾病（CMD）的人群其支链氨基酸（BCAA）和芳香族氨基酸（AAA）的系统水平升高。然而，关于支链氨基酸和芳香族氨基酸与亚洲印度人（AI）和黑人非洲人（BA）人群代谢综合征及其组成部分的关联知之甚少。
本研究旨在描述支链氨基酸和芳香族氨基酸与 AI 和 BA 人群代谢综合征、其各个组成部分和胰岛素抵抗的关系。
使用来自 AI（n=349）和 BA（n=369）受试者的血清样本，通过超高压液相色谱串联质谱（UPLC-MS/MS）测量支链氨基酸和芳香族氨基酸的水平。对所有受试者进行人体测量、人口统计学和心血管代谢变量的测量。
与 BA 相比，AI 中的支链氨基酸和芳香族氨基酸总和更高。支链氨基酸和芳香族氨基酸与胰岛素抵抗、代谢综合征及其各个组成部分呈正相关。在未调整的回归模型中，这一点尤其适用于 AI 受试者。然而，这些关联在调整协变量，特别是内脏脂肪组织（VAT）后变得不显著。在调整协变量后，BA 中的甘油三酯水平与缬氨酸和亮氨酸水平仍显著相关。最后，我们发现，在这两个群体中，空腹循环支链氨基酸和芳香族氨基酸水平与 VAT 密切相关。
本研究确定了血清缬氨酸和亮氨酸水平与 BA 中甘油三酯的特定关联。在 AI 中观察到氨基酸与 CMD 的关联，但发现这是由 VAT 引起的混杂因素所致。需要进一步的研究来确定支链氨基酸和芳香族氨基酸是否是 CMD 的病因因素，以及 VAT 如何调节它们的血清水平。
