Figure 3.

Loss of hepatic FGF21 impairs glucose uptake into BAT in vivo. Plasma glucose area under the curve (AUC) (A), plasma insulin levels (B), and rates of glucose uptake (C) in unanesthetized male WT and FGF21 LivKO fed HFD for 6 weeks. All mice were administered [³H]2-deoxyglucose after an overnight fast; glucose uptake was measured in BAT, eWAT, subcutaneous WAT, heart, and skeletal muscle (tibialis anterior) (n = 5–7/group). Glucose uptake assays in primary brown adipocytes (D) and primary white adipocytes (E) treated with vehicle (Veh), insulin (100 nmol/L), FGF21 (1 µg/mL), or FGF21 plus insulin. Experiments were performed in triplicate twice. Data are presented as mean ± SEM. Different lowercase letters represent statistical significance (a, P < 0.05; b, P < 0.01; d, P < 0.001).