Fig. 6
Transplantation of SAT from WT to FGF21KO mice improves insulin sensitivity. a Schematic diagram of transplantation strategy. After 8-week HFD induction, a total of 0.85g-subcutaneous fat from WT or FGF21KO donor mice was transplanted into the inguinal area of FGF21KO host mice (KO→KO and WT→KO groups). WT Sham and FGF21KO Sham groups had surgery in the same area, but no fat was transplanted. Eighteen days after fat transplantations, various measurements were carried out. n = 6. These results were reproduced in three independent experiments. b Evans blue i.v. injection into host mice to prove vascularization of the fat grafts at 2 weeks after transplantation. c Hematoxylin and eosin-stained fat grafts showed normal morphology of adipocytes. Scale bar = 50 μM. d–f GTT (d), AUC analysis of GTT (e) and ITT performed in all four groups including WT Sham, KO Sham, KO→KO and WT→KO (f). *comparison of WT Sham, vs. KO Sham, #comparison of KO Sham vs. WT→KO. g Whole-body insulin sensitivity as quantified by GIR. h–l HGP in the basal and clamp state (h), insulin-stimulated 2-[14C]DG uptake in inguinal SAT (i), epiVAT (j), muscle (k) and BAT among all four groups (l). (m) Immunoblot of in vivo insulin-stimulated SAT in transplantation cohort. n = 6. Representative immunoblots showing phospho (S473) and total Akt in the endogenous SAT of all four groups. The tissues were collected at 10 min after single i.v. injection of insulin (1 U kg−1). The bar chart shows densitometric analysis of phosphorylation levels. n,o Change of serum adiponectin (n) and adiponectin expression in different fat depots (SAT and VAT) in the WT Sham, KO Sham, KO→KO and WT→KO groups at 18th day after fat transplantation (o). n = 6. These results were reproduced in three independent experiments. Data are presented as mean ± s.e.m. Significance was determined by Student’s t-test analysis (h), one-way ANOVA (e, g, i–o) and two-way ANOVA with Bonferroni multiple-comparison analysis (d, f). * or # P < 0.05, ** or ## P < 0.01, ***P < 0.001, NS non-significance
