Extended Data Fig. 8: DLL4 blockade prevents atrophy of human skeletal myotubes.
From: The endothelial Dll4–muscular Notch2 axis regulates skeletal muscle mass
a–i, Effect of coculture of human skeletal muscle myotubes with human umbilical vein endothelial cells (HUVECs) in the transwell culture system. a, Schematic of the transwell culture system. HUVECs were transfected with control siRNA (si-Cont) or siRNA against DLL4 (si-DLL4) 1 day before coculture with myotubes. b, DLL4 protein expression in si-Cont- and si-DLL4-transfected HUVEC lysates and supernatants (Sup) of those culture media. Immunodetection for β-tubulin and ponceau staining served as internal controls. c, Representative images of MyHC-positive myotubes (scale bar, 50 µm). d,e, Quantitative data of myotube diameters (d) and fusion index (e) (n = 4 well per condition, myotubes in more than 3 field of view (10×)/well were measured). f, Effects of treatment with 500 ng ml−1 anti-DLL4 neutralizing antibody (αDLL4) or control antibody (αCont) on human myotubes–HUVECs co-culture. g, Representative images of MyHC-positive myotubes (scale bar, 50 µm). h,i, Quantitative data of myotube diameters (h) and fusion index (i) (n = 4 well per condition, myotubes in more than 3 field of view (10×)/well were measured). Data represent the mean ± s.e.m., and points are individual mice. ***P < 0.001, NS (not significant) as determined by two-way repeated-measures ANOVA followed by Tukey’s multiple comparisons post-hoc test (d,h).
