Temporal patterns of circulating leptin levels in lean and obese adolescents: Relationships to insulin, growth hormone, and free fatty acids rhythmicity
Temporal patterns of circulating leptin levels in lean and obese adolescents: Relationships to insulin, growth hormone, and free fatty acids rhythmicity
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DOI：
10.1210/jc.86.1.90
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发表时间：
2001-01-01
影响因子：
5.8
通讯作者：
Caprio, S
中科院分区：
文献类型：
--
作者：
Heptulla, R;Smitten, A;Caprio, S
营养状况的变化，如肥胖，显著影响胰岛素、瘦素、生长激素分泌和游离脂肪酸(FFA)水平。我们连续24小时测量瘦身和肥胖青少年的循环瘦素、胰岛素、生长激素和游离脂肪酸水平，以确定：1)青少年肥胖对瘦素浓度日变化的影响；2)循环瘦素水平的昼夜模式与胰岛素、生长激素和游离脂肪酸水平之间的时间关系。在青春期，我们发现循环血浆瘦素水平的24小时曲线遵循双峰模式，最低浓度出现在下午早些时候，夜间升高从午夜开始，并在清晨达到顶峰。肥胖青少年瘦素水平日变化的时间进程与瘦身对照组无明显差异。然而，值得注意的是，肥胖女孩的瘦素24小时游和瘦素昼夜比率低于瘦女孩。在肥胖青少年中，平均生长激素水平在白天和晚上的变化明显小于瘦身对照组。白天，瘦和肥胖青少年的FFA水平在餐前和餐后都有明显的升高和下降，而午夜后FFA水平都有所上升。瘦身和肥胖男女儿童0800h~2000h平均胰岛素水平与瘦素峰值呈显著正相关(r=0.63P<；0.001)。各组瘦素峰值与夜间生长激素水平下面积呈负相关(r=-0.31P<；0.0003)，与游离脂肪酸夜间峰值呈正相关(r=0.45P<；0.004)。综上所述，我们报告了肥胖的青春期女孩的瘦素水平的相对昼夜漂移。这种异常的节律性可能在一定程度上解释了他们的瘦素抵抗状态。夜间瘦素水平的上升与生长激素和游离脂肪酸水平的夜间上升是平行的。还需要更多的研究来测试脂肪衍生的多肽和人类生长激素轴之间的潜在联系。
Alterations in nutritional status, such as obesity, markedly influence insulin, leptin, GH secretion, and free fatty acid (FFA) levels. We measured every hour for 24 h circulating leptin, insulin, GH, and FFA levels in lean and obese adolescents to determine: 1) the impact of adolescent obesity on the diurnal changes in leptin concentrations; and 2) the temporal relationships between the diurnal patterns of circulating leptin levels and insulin, GH, and FFA levels. During puberty, we found that the 24-h profile of circulating plasma leptin levels follows a bimodal pattern with minimal concentrations occurring early in the afternoon and a nocturnal elevation starting after midnight and culminating early morning. The time course of the diurnal variation in leptin levels in the obese adolescents was not different from that in lean controls. Of note, however, in obese girls leptin 24-h excursion and leptin night to day ratio were lower than those found in lean girls. in obese adolescents, mean GH levels Varied significantly less during the day and night than lean controls. During the day, there were distinct preprandial increases and postprandial decreases in FFA levels, whereas after midnight FFA levels rose in both lean and obese adolescents. A significant positive correlation was found between mean plasma insulin levels between 0800 h and 2000 h and peak in leptin in lean and obese girls and boys (r = 0.63, P < 0.001). Peak leptin was inversely correlated with the area under the nocturnal GH levels in all groups (r = -0.31, P < 0.0003), whereas it was positively correlated with the nocturnal peak in FFA levels (r = 0.45, P < 0.004). In summary, we report in obese adolescent girls a blunted relative diurnal excursion in leptin levels. This abnormal rhythmicity may, in part, explain their leptin resistance state. The nocturnal rise in leptin was paralleled by a nocturnal rise in GH and FFA levels. Additional studies are needed to test the potential link between the adipose-derived peptide and GH axis in humans.