Fig. 3
From: A two-strata energy flux system driven by a stress hormone prioritizes cardiac energetics
FGF21 restoration improves heart dysfunction under stress by promoting mitochondrial energy flux and macronutrient flexibility. a Effects of increased energy flux via a high-fat diet (HFD) and rhFGF21 on heart rate (HR) in Fgf21-/- (n = 12) vs WT (n = 12) mice. w, week. See Fig. S7a. b Area-under-curve (AUC) analysis of HR changes in a. See Fig. S7b. c, d Changes in EF and CO in the same groups as in a. See Fig. S7c. e, f Changes in serum triglycerides (TG) and free fatty acids (FFA) in Fgf21-/- (n = 6) vs WT (n = 6) mice as in a, as well as after 3-week rhFGF21 treatment. For other hepatic and serum metabolic parameters, see Fig. S8a–g. For the HFD effects on cardiac mitochondria, see Fig. S8h. For glucose intolerance status, see Fig. S8i, j. g Time courses of the effects of FGF21 restoration on HR via AAV-mediated overexpression in Fgf21-/- (n = 12) vs AAV control (n = 12) mice. See Fig. S9a for experimental scheme and Fig. S9b for HR excursion curves. h, i Time-dependent changes in MEE, EF and LVESD after FGF21 restoration in Fgf21-/- mice (n = 31). See Fig. S9c–e. j, k Energy expenditure (RER, VCO2, HEAT) by indirect calorimetry under basal conditions, after 48 hours of starvation, and after 24 hours of refeeding in the mouse groups as in g. See Fig. S10a for experimental design and Fig. S10b–i for other analyses. For changes in energy expenditure parameters between the Fgf21-/- and WT mice under similar conditions, see Fig. S11a–d. CN, control vector. SV, starvation. Left, excursion curves. Right, AUC of the respective curve. The AUC plot without a title indicates total (light + dark) AUC. l n = 18 per group. m n = 6 per group. l–p Changes in food intake and water consumption in the same groups and conditions as in j–k. Data are means ± s.e.m.s; (e–p) two-tailed unpaired Student’s t test; (a–d) ordinary one-way ANOVA followed by Tukey’s test
