Figure 3.

Intermittent fasting induced adipose-VEGF expression and angiogenesis depend on liver FGF21 signaling. Mice were fed with HFD ad libitum or time-restricted access to food for 16 weeks. HA means WT mice eating a high-fat diet with ad libitum, HT means WT mice eating a high-fat diet with time-restricted access to food, KOHA means FGF21 LKO mice eating a high-fat diet with ad libitum, KOHT means FGF21 LKO mice eating a HFD with time-restricted access to food. (A) Schematic illustration of the experimental design. (B) Body weight. (C) Representative HT mice were remarkably leaner than the HA mice. (D) Body composition was evaluated by EchoMRI. (E) Serum FGF21 levels as determined by enzyme-linked immunosorbent assay. (F) A representative macroscopic image illustrating increased vascularization in iWAT of HT mice, compared to HA mice but not in FGF21 LKO mice. (G) Real-time quantitative PCR analysis for mRNA expression levels of Vegfa in eWAT and iWAT. Representative protein levels for VEGF in eWAT (G) and iWAT (I). (J) Immunofluorescence staining of CD31 (scale bar, 100 mm) in eWAT and iWAT, illustrating IF increased vascularization in WT mice but not in FGF21 LKO mice. Data are mean ± SEM; n = 6–8/group. Statistical significance was evaluated by the 2-way ANOVA test and the Tukey’s test for multiple comparisons to determine differences between each group. HA vs HT, *P < 0.05, **P < 0.01; labeled means without a common letter differ, P < 0.05.