Figure 1.
Body weight and cumulative food consumption in sedentary and wheel-running mice.
(A) Body weight in mice housed in a sedentary condition (SED; unfilled circles) or given free-access to a running-wheel (RW; filled circles) throughout experimental period. Mice were weighed weekly between ZT2 and ZT3 and data are shown as means ± SEM (n = 28). (B) Cumulative food consumption during light (ZT0–12) and dark (ZT12–24) period in SED (unfilled bar) and RW (filled bar) mice. Food consumption by mice was measured daily during the fourth week of access to running-wheels. Data are shown as means ± SEM (n = 14). *P < 0.01, significant differences between RW and SED mice. ZT, Zeitgeber time.
Table 1.
Relative weight of liver, white and brown adipose tissue, skeletal muscle, heart and lungs of sedentary and wheel-running mice.
Figure 2.
Circadian rhythm of behavioral activity, core body temperature and food intake in sedentary and wheel-running mice.
(A) Representative actogram in mice housed with access to running-wheels (RW) for four weeks. Light/dark cycles are shown as white/black bars, respectively. (B) Hourly distance of wheel-running by RW mice over 24 h calculated based on numbers of revolutions/h during fourth week of experiment and running-wheel diameter. Gray shading indicates dark period. Data are shown as means ± SEM (n = 3–4). (C) Core body temperature (Tb) rhythm for 24 h under 12 h light-12 h dark cycle. Mice were housed under sedentary (SED; red line) conditions or given free access to running-wheels (RW; blue line) for four weeks and Tb was measured during fourth week. Data are shown as means ± SEM (n = 4–5). Gray shading indicates dark period. (D) Circadian rhythm of food intake for 24 h under 12 h light-12 h dark cycle. Food intake was measured every 30 min during fourth week of the experiment in SED (unfilled circles) and RW (filled circles) mice. Data are shown as means ± SEM (n = 3–4). Gray shading indicates dark period. *P < 0.05 and **P < 0.01, significant differences between SED and RW mice at corresponding Zeitgeber times (ZT).
Figure 3.
Plasma hormone concentrations in sedentary and wheel-running mice.
Plasma corticosterone (A), leptin (B) and ghrelin (C) concentrations at indicated times in mice housed under sedentary (SED; unfilled circles) conditions or given free access to running-wheels (RW; filled circle). Gray shading indicates dark period. Data are shown as means ± SEM (n = 4–5). *P < 0.05 and **P < 0.01, significant differences between SED and RW mice at corresponding Zeitgeber times (ZT).
Figure 4.
Circadian expression of clock and clock-controlled genes in sedentary and wheel-running mice.
Messenger RNA expression of clock and clock-controlled genes in liver (A), white (B) and brown (C) adipose tissue and skeletal muscle (D) from mice housed under sedentary (SED; unfilled circles) conditions or given free-access to running-wheels (RW; filled circles). Gray shading indicates dark period. Data are shown as means ± SEM (n = 4–5). *P < 0.05 and **P < 0.01, significant differences between SED and RW mice at corresponding Zeitgeber time (ZT).
Table 2.
Cosinor analysis of clock gene expression in liver, white and brown adipose tissues and skeletal muscle of sedentary and wheel-running mice.
Figure 5.
Circadian expression of clock-controlled metabolism-related genes in the liver.
Messenger RNA expression of glucose (A) and lipid (B) metabolism-related genes in livers of mice housed under sedentary conditions (SED; unfilled circles) or given free access to running-wheels (RW; filled circles). Gray shading indicates dark period. Data are shown as means ± SEM (n = 4–5). *P < 0.05 and **P < 0.01, significant differences between SED and RW mice at corresponding Zeitgeber time (ZT).