Plasma ghrelin levels and hunger scores in humans initiating meals voluntarily without time- and food-related cues
Plasma ghrelin levels and hunger scores in humans initiating meals voluntarily without time- and food-related cues
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DOI：
10.1152/ajpendo.00582.2003
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发表时间：
2004-08-01
影响因子：
5.1
通讯作者：
Chapelot, D
中科院分区：
文献类型：
--
作者：
Cummings, DE;Frayo, RS;Chapelot, D
Ghrelin是一种促食欲激素，与进餐有关，部分原因是餐前循环水平升高。由于先前的人类研究已经检查了按已知时间表进食的受试者，因此观察到的餐前生长激素释放肽增加可能是进餐预期的次要后果。胃饥饿素在进餐开始中的因果作用将得到更好的支持，如果餐前增加发生在自发开始进餐之前，而不是由外部线索提示。我们测量了在没有与时间或食物相关的线索的情况下自愿开始进餐的人类受试者的血浆ghrelin水平。在预定的午餐和自由要求的晚餐之间每5分钟抽取样品，并使用视觉模拟量表获得饥饿评分。胰岛素、葡萄糖、脂肪酸、瘦素和甘油三酯也进行了测量。所有受试者的Ghrelin水平在第一餐后不久下降。除一名受试者外，所有受试者的餐前增加发生在广泛的餐间间隔（IMI; 320-425分钟）内。饥饿分数和ghrelin水平显示出相似的时间分布和相似的相对差异，在午餐和晚餐之间的幅度。1例受试者显示餐前胃饥饿素未增加，也是唯一一个餐间胰岛素水平未恢复至基线的个体。这一发现，沿着生长激素释放肽和胰岛素曲线下面积值之间的相关性，表明胰岛素在生长激素释放肽调节中的作用。我们观察到，在没有时间或食物相关线索的情况下，自愿开始进餐的人餐前胃饥饿素水平增加，这些水平和饥饿评分之间的重叠与胃饥饿素在进餐开始中的作用一致。
Ghrelin is an orexigenic hormone that is implicated in meal initiation, in part because circulating levels rise before meals. Because previous human studies have examined subjects fed on known schedules, the observed preprandial ghrelin increases could have been a secondary consequence of meal anticipation. A causal role for ghrelin in meal initiation would be better supported if preprandial increases occurred before spontaneously initiated meals not prompted by external cues. We measured plasma ghrelin levels among human subjects initiating meals voluntarily without cues related to time or food. Samples were drawn every 5 min between a scheduled lunch and a freely requested dinner, and hunger scores were obtained using visual analog scales. Insulin, glucose, fatty acids, leptin, and triglycerides were also measured. Ghrelin levels decreased shortly after the first meal in all subjects. A subsequent preprandial increase occurred over a wide range of intermeal intervals (IMI; 320-425 min) in all but one subject. Hunger scores and ghrelin levels showed similar temporal profiles and similar relative differences in magnitude between lunch and dinner. One subject displayed no preprandial ghrelin increase and was also the only individual whose insulin levels did not return to baseline between meals. This finding, along with a correlation between area-under-the-curve values of ghrelin and insulin, suggests a role for insulin in ghrelin regulation. The preprandial increase of ghrelin levels that we observed among humans initiating meals voluntarily, without time- or food-related cues, and the overlap between these levels and hunger scores are consistent with a role for ghrelin in meal initiation.