Extended Data Fig. 1: FGF21 has no obvious effects on GSIS.
From: β-Klotho promotes glycolysis and glucose-stimulated insulin secretion via GP130
a, Illustration of the experimental design for the effects of recombinant mouse FGF21 (rmFGF21) protein on GSIS in islets isolated from 20-week-old male C57BL/6J lean, diet-induced obese (DIO, fed with a high-fat diet for 12 weeks) and db/db mice. b, Insulin secretion capacities of isolated islets treated with 50 nM rmFGF21 protein for 0-72 h under 2.8 mM or 16.7 mM glucose condition (n = 6 mice). c, Insulin secretion capacities of isolated islets treated with rmFGF21 protein at 0, 50, 100 nM for 48 h under 2.8 mM or 16.7 mM glucose condition (n = 6 mice). d, Islets isolated from lean, DIO and db/db mice were fasted for 12 h and treated with 0, 50, 100 nM rmFGF21 protein for 10 min, followed by examination of p-Erk (Thr202/Tyr204) and t-Erk protein levels by Western blot. Similar results were obtained from three independent experiments. e, Rat INS-1E (n = 6 independent cultures) and mouse MIN6 β-cells (n = 7 independent cultures) were treated with 0, 50, 100 nM rmFGF21 protein for 48 h before exposure to 2.8 mM or 16.7 mM glucose for 30 min. Insulin concentration in the conditioned medium was measured and normalized to cell protein concentrations. f-g, Blood glucose levels (f) and serum insulin levels (g) in male 14-week-old WT (FGF21+/+) and Fgf21 KO (FGF21-/-) mice under feeding or fasting conditions (n = 8 mice). h-i, GTT (h, n = 8 mice) and GSIS (i, n = 6 mice) were performed in male FGF21+/+ and FGF21-/- mice on regular diet for 12 weeks and the values of area under curve (AUC) were quantified. j, Dynamic insulin secretion under basal or high glucose condition was measured in cultured islets isolated from male FGF21+/+ and FGF21-/- mice on regular diet for 12 weeks (n = 6 mice). Data are presented as mean ± SEM.
