BACKGROUND There is no consensus in the field regarding the optimal method for the expression of metabolic flux data, such as glucose disposal rates during hyperinsulinemic-euglycemic clamp experiments. Several normalization methods are in use today, but their impact on study outcomes is rarely discussed. METHODS We illustrate this issue using clamp data from 92 lean and 66 obese subjects. Glucose kinetics and insulin sensitivity were determined during hyperinsulinemic-euglycemic clamp studies using [6,6-2H2]glucose. From this single dataset, we calculated 21 expression methods for the glucose disposal rate during hyperinsulinemic conditions. RESULTS AND DISCUSSION With most normalization methods, the obese subjects demonstrated reduced insulin-stimulated glucose disposal as compared to the lean subjects. However, depending on the normalization method, glucose disposal rates in obese subjects ranged from 26 ± 1% to 207 ± 10% of glucose disposal rates in lean subjects. We conclude that data normalization methods greatly impacted metabolic flux outcomes in our dataset of lean and obese subjects. There is no compelling evidence to select one method over the other, but we encourage authors in the metabolic arena to think about, and provide a rationale for, the best normalization method for their specific research questions.

中文翻译：

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人体钳位研究期间代谢通量数据的标准化。

背景技术在关于代谢通量数据的表达的最佳方法（例如在高胰岛素-正常血糖钳制实验中的葡萄糖处置率）方面，尚无共识。今天使用了几种归一化方法，但是很少讨论它们对研究结果的影响。方法我们使用来自92位瘦弱和66位肥胖受试者的钳位数据来说明此问题。在高胰岛素-正常血糖钳夹研究中，使用[6,6-2H2]葡萄糖测定了葡萄糖动力学和胰岛素敏感性。从这个单一的数据集中，我们计算了高胰岛素状态下葡萄糖处置率的21种表达方法。结果与讨论与正常人相比，大多数正常化方法显示，肥胖人的胰岛素刺激的葡萄糖处置减少。然而，根据标准化方法的不同，肥胖受试者中的葡萄糖处置率介于瘦者中的葡萄糖处置率的26±1％到207±10％之间。我们得出结论，数据标准化方法极大地影响了我们肥胖和肥胖受试者数据集中的代谢通量结果。没有令人信服的证据选择一种方法来替代另一种方法，但是我们鼓励代谢领域的作者考虑针对他们的特定研究问题的最佳归一化方法，并为其提供理论依据。