Extended Data Fig. 9: Effects of αDll4 or Fc-fused Dll4 recombinant protein on muscle atrophy.

a–c, Effect of treatment with EC-conditioned media (EC-CM) on myofibres. a, Primary ECs were isolated from hindlimb muscle tissues. Concentrated EC-CM were added into culture media containing wild-type EDL myofibres. Myofibres were then cultured with the addition of 500 ng ml⁻¹ anti-Dll4 neutralising antibody (αDll4) or control antibody (αCont) for 48 hours. b, Representative images of myofibres (scale bar, 50 µm). c, Quantitative data of myofibre diameters (n = 4 mice per condition, >15 individual myofibres per mouse were measured). d–f, Effect of treatment with Fc-fused Dll4 recombinant protein (rDll4-Fc) on myofibres co-cultured with primary ECs. d, Wild-type EDL myofibres were co-cultured with ECs isolated from hindlimb muscle tissues with the addition of 500 ng ml⁻¹ rDll4-Fc for 48 hours. e, Representative images of myofibres (scale bar, 50 µm). f, Quantitative data of myofibre diameters (n = 4 mice per condition, >15 individual myofibres per mouse were measured). g–i, Effect of rDll4-Fc administration on diabetic muscle atrophy in vivo. g, Wild-type mice were intraperitoneally injected with STZ (150 mg kg⁻¹ body weight; DM) or vehicle (Veh) and analysed 14 days after the injection. Mice were administered with rDll4-Fc at day 7, 9, 11, and 13 following the STZ infusion. PBS was used as a control. h, Blood glucose levels 14 days after STZ infusion (n = 5). i, Muscle weight normalised to body weight. Data represent the means ± s.e.m., and points indicate individual mice. *P < 0.05, **P < 0.01, ***P < 0.001 NS (not significant) as determined by two-way ANOVA followed by Tukey’s multiple comparisons post-hoc test (c,f,h,i).