Centre for Research Excellence in Translating Nutritional Sciences to Good Health, Adelaide Medical School, The University of Adelaide, Adelaide 5000, Australia.
Department of Clinical Biochemistry, Bispebjerg and Frederiksberg Hospital, Copenhagen, Denmark.
Peptides. 2023 Mar;161:170941. doi: 10.1016/j.peptides.2023.170941. Epub 2023 Jan 6.
Gastric emptying (GE) is a major determinant of the postprandial glycemic and insulinemic responses in health and type 2 diabetes (T2D). However, the effect of GE on the postprandial glucagon response, which is characteristically augmented in T2D, is unknown. This study examined the relationship between plasma glucagon and GE of a standardized mixed meal in individuals with well-controlled T2D. 89 individuals with T2D (HbA1c 6.6 ± 0.1%) consumed a mashed potato meal labeled with 100 µL C-octanoic acid between 0 and 5 min. Venous blood was sampled frequently over 4 h for measurements of blood glucose and plasma glucagon. The gastric half-emptying time (T50) was calculated by quantification of C in the breath. Blood glucose peaked at t = 90 min after the meal. Plasma glucagon increased to a peak at t = 30 min and then decreased to a nadir at t = 180 min. The T50 was 68.3 ± 1.6 min. The incremental area under the plasma glucagon curve between t = 0-30 min (glucagon iAUC) was related inversely to the T50 (r = -0.23, P = 0.029), while the increase in blood glucose at t = 30 min was related directly to the plasma glucagon iAUC (r = 0.25, P = 0.018). Accordingly, individuals with relatively faster GE exhibited higher postprandial glucagon and glucose levels (ANOVA: P<0.01 for each). In well-controlled T2D, the early postprandial glucagon response to a mixed meal is related to the rate of GE, and predictive of the initial glycemic response. These observations suggest that a reduction in plasma glucagon may contribute to the effect of dietary and pharmacological strategies which reduce postprandial glycemia in T2D by slowing GE.
胃排空（GE）是健康和 2 型糖尿病（T2D）患者餐后血糖和胰岛素反应的主要决定因素。然而，对于餐后胰高血糖素反应的影响尚不清楚，而这种反应在 T2D 中通常会增强。本研究旨在研究 2 型糖尿病患者中标准化混合餐的胃排空与血浆胰高血糖素之间的关系。89 名 T2D 患者（HbA1c 6.6±0.1%）在 0 至 5 分钟之间摄入含有 100µL C-辛酸的土豆泥餐。在 4 小时内频繁采集静脉血样，以测量血糖和血浆胰高血糖素。通过呼吸中 C 的定量计算胃排空的半衰期（T50）。餐后 90 分钟时血糖达到峰值。餐后 30 分钟时，血浆胰高血糖素升高至峰值，然后在 180 分钟时降至最低点。T50 为 68.3±1.6 分钟。餐后 0 至 30 分钟（胰高血糖素 iAUC）的血浆胰高血糖素曲线下面积增量与 T50 呈负相关（r=-0.23，P=0.029），而 30 分钟时血糖的增加与血浆胰高血糖素 iAUC 呈正相关（r=0.25，P=0.018）。因此，胃排空较快的个体表现出更高的餐后胰高血糖素和血糖水平（方差分析：每个 P<0.01）。在控制良好的 T2D 中，混合餐后的早期胰高血糖素反应与 GE 速度有关，并可预测初始血糖反应。这些观察结果表明，降低血浆胰高血糖素可能有助于通过减缓 GE 来降低 T2D 餐后血糖的饮食和药物策略的效果。
