社会时差在儿童青少年肥胖发生中的作用及其相关机制研究

Insufficient sleep is associated with adverse physical and psychological consequences in children, and is identified as high risk factor of obesity. School-aged children and adolescents tend to compensate for weekday sleep deficit by increasing weekend sleep duration, however weekend sleep compensation inevitably causes irregular circadian rhythm which is defined as social jetlag. Animal studies indicated that the disruption of the circadian rhythm can lead to derangement of metabolism, thus predisposing to metabolic disorders such as obesity. But very little work has been conducted in humans, especially for children and adolescents. This study is designed to focus on children and adolescents whose social jetlag are most acute, and explore the independent effect of social jetlag on obesity indices through an epidemiological study. Meanwhile, sleep intervention study with self comparison cross-over study design is launched to investigate the association between social jetlag and metabolic indices such as leptin and ghrelin, further the functional MRI scan is used to explore the mechanism of the effect of social jetlag on the function of energy regulation center in the brain. These research results are expected to stress the importance effect of sleep rhythm on metabolism, and integrate a new strategy on healthy sleep as well as early onset obesity prevention and treatment program.

睡眠不足对儿童身心健康有显著影响，也是儿童肥胖发生的高危因素。针对平时睡眠不足的现状，儿童青少年通常采取周末补偿睡眠的方法，但补偿睡眠的同时却会导致明显的社会时差，即生物节律紊乱的存在。动物实验研究已证实生物节律紊乱直接影响机体代谢水平进而引发肥胖，但基于人群尤其是儿童青少年的研究仍非常缺乏。本研究拟聚焦社会时差问题最突出的儿童青少年人群，通过流行病学研究探索社会时差对儿童青少年肥胖发生的独立影响；同时采用自身对照、交叉实验设计，通过睡眠干预实验研究社会时差对瘦素、胃泌素等代谢指标的直接影响，并利用功能性磁共振成像进一步探索社会时差对大脑摄食中枢及相关脑区功能的影响。本研究将进一步揭示睡眠节律性在维持机体代谢稳定中的重要性，其结果将为儿童青少年健康睡眠指导及肥胖干预提供新的理论依据。

睡眠不足对儿童身心健康有显著影响，也是儿童肥胖发生的高危因素。针对平时睡眠不足的现状，儿童青少年通常采取周末补偿睡眠的方法，但补偿睡眠的同时却会导致明显的社会时差，即生物节律紊乱的存在。动物实验研究已证实生物节律紊乱直接影响机体代谢水平进而引发肥胖，但基于人群尤其是儿童青少年的研究仍非常缺乏。本研究聚焦社会时差问题最突出的儿童青少年人群，通过多阶段整群抽样抽取初中生和高中生，探索社会时差对儿童青少年肥胖发生的独立影响，研究发现社会时差在青少年较为普遍，社会时差1.20±0.91h，且社会时差对儿童青少年的肥胖存在显著作用，独立于睡眠时间、睡眠质量和睡眠类型，具体表现在社会时差≥2h的青少年发生肥胖的几率是社会时差＜1h的青少年的1.68倍；此外静息-活动节律参数如日内变异性、夜间L5水平、相对振幅、M10启动时间对BMI水平也具有独立的效应。通过睡眠干预实验研究，利用功能性近红外光谱技术检查探索社会时差对大脑摄食中枢及相关脑区功能的影响，研究发现相比规律睡眠阶段，受试者社会时差阶段在看到高能量食物、低能量食物时在前额叶表现出较低水平的激活。本研究结果揭示了睡眠节律性在维持机体代谢稳定中的重要性，为儿童青少年健康睡眠指导及肥胖干预提供新的理论依据。