Division of Endocrinology and Metabolism, Department of Internal Medicine, Shuang Ho Hospital, School of Medicine, College of Medicine, Taipei Medical University, Taiwan, ROC.
Diabetes Res Clin Pract. 2013 Jun;100(3):391-7. doi: 10.1016/j.diabres.2013.03.022. Epub 2013 Apr 13.
The aim of this study was to evaluate the relative importance of insulin sensitivity (SI), and the first (1st ISEC) and second phase insulin secretion (2nd ISEC) in the development of type 2 diabetes (T2D) in Chinese subjects.
A total of 96 subjects, including 19 with normal fasting glucose, 21 with pre-diabetes, and 56 with T2D were enrolled. Subjects underwent a modified low dose graded glucose infusion (M-LDGGI; a simplified version of Polonsky's method) and frequently sampled intravenous glucose tolerance test. The results were interpreted as the slope of the changes of plasma insulin against the glucose levels. By observing the respective percentage reduction, the deterioration rate of each parameter was compared.
As fasting plasma glucose (FPG) levels increased, SI decreased mildly and non-significantly, while the 1st and 2nd ISECs decreased more dramatically and significantly. More importantly, the decrease of the 1st ISEC from baseline was greater than that of the 2nd ISEC.
Since the 1st ISEC decreased the most with increasing FPG levels, it is concluded that the 1st ISEC is the key trigger of T2D development. On the contrary, the 2nd ISEC remained more stable across increasing FPG levels. This latter finding may explain the effectiveness of insulin secretagogues during the early stage of T2D. The results of this study can be helpful in the development of interventions aimed at stopping the progression and/or treating T2D in Chinese populations.
本研究旨在评估胰岛素敏感性（SI）、第一时相胰岛素分泌（1st ISEC）和第二时相胰岛素分泌（2nd ISEC）在中国人中 2 型糖尿病（T2D）发展中的相对重要性。
共纳入 96 例受试者，包括 19 例空腹血糖正常者、21 例糖尿病前期者和 56 例 T2D 患者。受试者接受改良低剂量分级葡萄糖输注（M-LDGGI；简化版 Polonsky 法）和频繁采样静脉葡萄糖耐量试验。结果解读为胰岛素与血糖水平变化的斜率。通过观察各自的百分比降低，比较每个参数的恶化率。
随着空腹血糖（FPG）水平的升高，SI 轻度且无显著下降，而 1st 和 2nd ISECs 则显著下降。更重要的是，从基线开始，1st ISEC 的下降幅度大于 2nd ISEC。
由于 1st ISEC 随着 FPG 水平的升高而下降最多，因此可以得出结论，1st ISEC 是 T2D 发展的关键触发因素。相反，2nd ISEC 在 FPG 水平升高时保持更稳定。这一发现可能解释了胰岛素促分泌剂在 T2D 早期阶段的有效性。本研究的结果有助于制定针对中国人群阻止 T2D 进展和/或治疗 T2D 的干预措施。
