Phoenix Epidemiology and Clinical Research Branch, Phoenix, AZ 85016, USA.
Institute of Diabetes and Clinical Metabolic Research, 24195 Kiel, Germany.
J Clin Endocrinol Metab. 2022 Aug 18;107(9):e3769-e3780. doi: 10.1210/clinem/dgac353.
A greater decrease in 24-hour energy expenditure (24hEE) during short-term fasting is indicative of a thrifty phenotype.
As ghrelin and the growth hormone (GH)/insulin-like growth factor 1 (IGF-1) axis are implicated in the regulation of energy intake and metabolism, we investigated whether ghrelin, GH, and IGF-1 concentrations mediate the fasting-induced decrease in 24hEE that characterizes thriftiness.
In 47 healthy individuals, 24hEE was measured in a whole-room indirect calorimeter both during 24-hour eucaloric and fasting conditions. Plasma total ghrelin, GH, and IGF-1 concentrations were measured by enzyme-linked immunosorbent assay after an overnight fast the morning before and after each 24-hour session.
During 24-hour fasting, on average 24hEE decreased by 8.0% (P < .001), GH increased by ~5-fold (P < .001), whereas ghrelin (mean +23 pg/mL) and IGF-1 were unchanged (both P ≥ .19) despite a large interindividual variability in ghrelin change (SD 150 pg/mL). Greater fasting-induced increase in ghrelin was associated with a greater decrease in 24hEE during 24-hour fasting (r = -0.42, P = .003), such that individuals who increased ghrelin by 200 pg/mL showed an average decrease in 24hEE by 55 kcal/day.
Short-term fasting induced selective changes in the ghrelin/GH/IGF-1 axis, specifically a ghrelin-independent GH hypersecretion that did not translate into increased IGF-1 concentrations. Greater increase in ghrelin after 24-hour fasting was associated with greater decrease in 24hEE, indicating ghrelin as a novel biomarker of increased energy efficiency of the thrifty phenotype.
短期禁食期间 24 小时能量消耗（24hEE）的更大降幅表明存在节俭表型。
由于 ghrelin 和生长激素（GH）/胰岛素样生长因子 1（IGF-1）轴参与了能量摄入和代谢的调节，我们研究了 ghrelin、GH 和 IGF-1 浓度是否介导了节俭表型特征的禁食诱导的 24hEE 降低。
在 47 名健康个体中，使用整个房间间接热量计在 24 小时能量平衡和禁食条件下测量 24hEE。在每个 24 小时会话之前和之后的清晨，在隔夜禁食后通过酶联免疫吸附测定法测量血浆总 ghrelin、GH 和 IGF-1 浓度。
在 24 小时禁食期间，平均 24hEE 下降 8.0%（P<0.001），GH 增加约 5 倍（P<0.001），而 ghrelin（平均增加 23 pg/mL）和 IGF-1 不变（两者 P≥.19），尽管 ghrelin 变化的个体间差异很大（SD 150 pg/mL）。禁食诱导的 GH 增加越大，24 小时禁食期间 24hEE 的下降越大（r = -0.42，P=0.003），因此 ghrelin 增加 200 pg/mL 的个体平均每天 24hEE 减少 55 千卡。
短期禁食引起了 ghrelin/GH/IGF-1 轴的选择性变化，特别是 ghrelin 独立的 GH 过度分泌，而没有转化为 IGF-1 浓度的增加。24 小时禁食后 ghrelin 的增加与 24hEE 的更大降幅相关，表明 ghrelin 是节俭表型能量效率增加的新生物标志物。
