Figure 1.

Increased fat content and reduced energy expenditure on MFD in SIRT1^+/− mice. A, Time course of body weight gain. Body weight (BW) was determined every 3–5 wk after 12 wk of age. B, Fat mass. C, Lean mass. The fat and lean mass were determined using NMR. D, Food intake. Food intake was monitored daily for 3 d. Average daily food intake (g) was converted into kilocalories and normalized with body weight (kg) and time (hours). E, TAG in feces of MFD-fed mice. F, Energy expenditure in SIRT1^+/− mice. Energy expenditure was examined in the mice at 13 wk of age using the metabolic chamber. The unit is kilocalories per kilogram of lean body mass. G, Carbohydrate (CHO) and fatty acid oxidation at night time normalized with the lean body mass. H, Substrate preference. It was expressed by RER, which is a volume ratio of oxygen consumed vs. CO₂ exhaled. I, Western blot of SIRT1 protein in liver tissue. Values are the means ± se (n = 7). *, P ≤ 0.05.