Purpose

The daily circadian cycle is known to modulate both feeding behavior and metabolism. As such, the timing of food consumption can play a role in regulating overall health. The purpose of this study is to determine whether fasting at different times of the day alters subsequent food consumption and levels of PYY_3–36, a hormone secreted after a meal which inhibits appetite.

Methods

Separate groups of mice were fasted at different times of the day: (1) start of the day, (2) middle of the day, (3) start of the night, and (4) middle of the night, and either injected with vehicle or PYY_3–36 to assess their subsequent food consumption patterns, PYY_3–36 levels, and glucose and insulin levels. We also investigated whether light exposure during the night would alter food consumption and PYY_3–36 levels after fasting.

Results

Mice fasted during the start of the daytime exhibited increased food consumption post-fast compared to mice fasted during the night. Injections of PYY_3–36 during the night were more effective in reducing food consumption compared to PYY_3–36 administration during the day. Constant light exposure suppressed food consumption after fasting and increased fasting PYY_3–36 levels.

Conclusions

These results indicate that mice exhibit distinct food consumption patterns after being presented with a fast at different times of the day. Light exposure also modulates both food consumption after a fast and levels of PYY_3–36.

中文翻译：

---

禁食时间导致夜间小鼠的食物消耗和 PYY3-36 水平不同。

目的

已知每天的昼夜节律周期调节摄食行为和新陈代谢。因此，食物消费的时间可以在调节整体健康方面发挥作用。本研究的目的是确定在一天中的不同时间禁食是否会改变随后的食物消耗和 PYY _{3-36 的}水平，PYY _3-36是一种在餐后分泌的抑制食欲的激素。

方法

不同组的小鼠在一天的不同时间禁食：（1）一天的开始，（2）一天的中间，（3）晚上的开始，和（4）半夜，并且要么注射载体或 PYY _3-36以评估其随后的食物消费模式、PYY _3-36水平以及葡萄糖和胰岛素水平。我们还调查了夜间光照是否会改变禁食后的食物消耗和 PYY _3-36水平。

结果

与夜间禁食的小鼠相比，在白天开始禁食的小鼠在禁食后表现出增加的食物消耗。PYY的注射_3-36在夜间均相比于PYY减少食物的消耗更有效_3-36白天管理。持续光照抑制禁食后的食物消耗并增加禁食 PYY _{3-36 的}水平。

结论

这些结果表明，小鼠在一天中的不同时间禁食后表现出不同的食物消耗模式。光照还可以调节禁食后的食物消耗和 PYY _{3-36 的}水平。