Fig. 4: Intact skeletal muscle glucose uptake and cellular signalling during exercise in homozygous TBC1D4 p.Arg684Ter variant carriers.
a, Graphical representation of the one-legged knee-extensor exercise model. b, Leg glucose uptake during 1 h of knee-extensor exercise and 3 h recovery. Leg glucose uptake in a rested leg before exercise: 6.7 ± 3.5 (controls) and 6.4 ± 1.8 (carriers) μmol min−1 kg−1 LLM. Average leg glucose uptake in a rested leg in exercise recovery: 4.3 ± 1.4 (controls) and 5.5 ± 1.4 (carriers) μmol min−1 kg−1 LLM. c,d, Skeletal muscle glycogen content (c) and GS activity (d) in a rested leg (rest) and exercised leg (exercise). e–l, Skeletal muscle protein phosphorylation of GS site 2 + 2a (Ser7 + Ser10) (e), AMPKα Thr172 (f), ACC Ser221 (g), P38 Thr180/Tyr182 (h), TBC1D1 Ser237 (i), PDH site 1 (Ser293) (j), p70S6K Thr389 (k) and TBC1D4 Ser704 (l). m, Representative immunoblots. ‡Different from basal (time 0) and rest in both groups (main effects). n = 5 in controls and in TBC1D4 carriers. Data are means ± s.e.m. Data were analysed using a two-way repeated ANOVA test (two-factor repeated) and two-tailed Student–Newman–Keuls post hoc analyses for multiple comparisons. Graphics in a created using BioRender.com. a.u., arbitrary units.
