a balanced diet is necessary for proper entrainment signals of the mouse liver clock均衡的饮食是必要的适当的夹带小鼠肝脏的信号时钟.pdfVIP

A Balanced Diet Is Necessary for Proper Entrainment Signals of the Mouse Liver Clock 1,2 1 2 1 Akiko Hirao , Yu Tahara , Ichiro Kimura , Shigenobu Shibata * 1 Laboratory of Physiology and Pharmacology, School of Advanced Science and Engineering, Waseda University, Shinjuku-ku, Tokyo, Japan, 2 Laboratory of Developmental Biology, School of Human Sciences, Waseda University, Saitama, Japan Abstract Background: The peripheral circadian clock in mice is entrained not only by light-dark cycles but also by daily restricted feeding schedules. Behavioral and cell culture experiments suggest an increase in glucose level as a factor in such feeding- induced entrainment. For application of feeding-induced entrainment in humans, nutrient content and dietary variations should be considered. Principal Finding: To elucidate the food composition necessary for dietary entrainment, we examined whether complete or partial substitution of dietary nutrients affected phase shifts in liver clocks of mice. Compared with fasting mice or ad libitum fed mice, the liver bioluminescence rhythm advanced by 3–4 h on the middle day in Per2::luciferase knock-in mice that were administered a standard mouse diet, i.e. AIN-93M formula [0.6–0.85 g/10 g mouse BW] (composition: 14% casein, 47% cornstarch, 15% gelatinized cornstarch, 10% sugar, 4% soybean oil, and 10% other [fiber, vitamins, minerals, etc.]), for 2 days. When each nutrient was tested alone (100% nutrient), an insignificant weak phase advance was found to be induced by cornstarch and soybean oil, but almost no phase advance was induced by gelatinized cornstarch, high-amylose cornstarch, glucose, sucrose, or casein. A combination of glucose and casein without oil, vitamin