Figure 1

Effect of vitamin D depletion on food intake and morphological parameters in old rats. (A) Food intake of control and vitamin D-depleted rats throughout the experimental period (n = 7 for control group and n = 9 for depleted group). Food intake was similar between the two groups except at week 20. Data presented are means ± SEM; *p < 0.05. (B) Body weight was measured throughout the experiment (n = 7 for control group and n = 9 for depleted group). Body weight of vitamin D-depleted rats increased throughout the experiment and became significantly different in comparison with their control counterparts after 13 weeks. Data presented are means ± SEM; *p < 0.05. At the beginning (C) and the end (D) of the depletion period, rats from each group were subjected to magnetic resonance imaging (MRI) using Echo MRI to determine body composition. Fat mass (FM) and lean mass (LM) were expressed as percentage of body weight (n = 7 for control group and n = 9 for depleted group). At the beginning of the experiment, body composition of D-depleted and control rat was similar. In contrast, percent fat mass was significantly increased by 43% (p < 0.05) whereas percent lean mass was reduced by 12% (p < 0.001) in D-depleted rats compared to controls at the end of the experiment. Data presented are means ± SEM; *p < 0.05 and **p < 0.01. (E) Body composition of rats from each group was determined at the beginning and the end of the experimental period, allowing us to calculate variation in fat mass (Δ FM) and lean mass (Δ LM) throughout the experiment (n = 7 for control group and n = 9 for depleted group). The loss of LM was greater and the gain of FM tended to be more important in vitamin-D depleted rats compared to control rats. Data presented are means ± SEM; *p < 0.05.