Sci Transl Med：夜节律失步为糖尿病创造条件

4月11日，根据国际著名杂志Science Translational Medicine上的一项新的研究披露，对国际旅行者、晚夜班员工或其他身体时钟失步的人来说，昼夜节律的破坏可损害身体制造胰岛素的能力，并潜在地为糖尿病的发生创造条件。这些发现帮助人们解释先前的对男性夜班工人有着较高的罹患肥胖症和糖尿病风险的研究。Orfeu Buxton及其同事们将21名实验参与者保持在受到控制的实验室环境中近乎6个星期，并在保持饮食和活动水平恒定的同时模拟对睡眠及昼夜节律的干扰。这些受试者在3个星期中在每个24小时的时段中只得到5.6小时的睡眠，并同时经历28个小时的昼夜节律天——这一状态类似于每天积累了4小时的飞行时差。

该团队发现，长期扰乱正常睡眠和昼夜节律会影响病人的分泌胰岛素的胰腺细胞，导致葡萄糖在其血液中的积聚（在某些情况下处于一个被认为是糖尿病前期的水平）。参与者还显示出代谢率的下降，它可转化为每年体重增加10磅以上。令人惊奇的是，研究人员发现，该试验的有害影响在经过9天的稳定的昼夜节律重新调整及恢复睡眠之后可大部分地被逆转。人们一般认为，从慢性睡眠丧失中恢复需要不止一个晚上，甚至需要一个周末，在旅行至一个新的时区后昼夜节律系统的重新同步化速度大约为一天一小时。

然而，研究人员不能确定在经过许多年的不稳定的昼夜节律扰乱及睡眠缺乏并已经造成损害之后如何才能可靠地改善健康。文章的作者提出，减少换班次的频率可使轮班工作者的昼夜节律干扰降至最低。每月改变一次的轮班工作可能比每隔几天改变一次或不规则改变的班次较少干扰昼夜节律。重要的是，人们注意到，这些参与者在试验期间没有得到任何的运动——人们需要做进一步的研究来探讨睡眠、运动和饮食之间的相互作用。（生物谷Bioon.com）

doi:10.1126/scitranslmed.3003200
PMC:
PMID:

Adverse Metabolic Consequences in Humans of Prolonged Sleep Restriction Combined with Circadian Disruption

Orfeu M. Buxton1,2,*, Sean W. Cain1,2, Shawn P. O’Connor1, James H. Porter1, Jeanne F. Duffy1,2, Wei Wang1,2, Charles A. Czeisler1,2 and Steven A. Shea1,2

Epidemiological studies link short sleep duration and circadian disruption with higher risk of metabolic syndrome and diabetes. We tested the hypotheses that prolonged sleep restriction with concurrent circadian disruption, as can occur in people performing shift work, impairs glucose regulation and metabolism. Healthy adults spent >5 weeks under controlled laboratory conditions in which they experienced an initial baseline segment of optimal sleep, 3 weeks of sleep restriction (5.6 hours of sleep per 24 hours) combined with circadian disruption (recurring 28-hour “days”), followed by 9 days of recovery sleep with circadian re-entrainment. Exposure to prolonged sleep restriction with concurrent circadian disruption, with measurements taken at the same circadian phase, decreased the participants’ resting metabolic rate and increased plasma glucose concentrations after a meal, an effect resulting from inadequate pancreatic insulin secretion. These parameters normalized during the 9 days of recovery sleep and stable circadian re-entrainment. Thus, in humans, prolonged sleep restriction with concurrent circadian disruption alters metabolism and could increase the risk of obesity and diabetes.