Fig. 6

p38α/β MAPKi treatment augments MuSC-mediated muscle production in mini-MEndR assay. A Schematic of the mini-MEndR assay workflow. MuSCs from YFP transgenic mice are isolated using the adapted magnetic assisted cell sorting (MACS) protocol and then engrafted onto the mini-myotube templates on day 6 of differentiation, followed by drug treatments and cardiotoxin-induced tissue injury. B Detailed experimental timeline for the mini-MEndR assay workflow. C,D; left Representative confocal images of MuSC-mediated (YFP⁺) myotube production in the injured mini-myotube templates produced with 18M (C) 19F (D) in response to treatment with DMSO or p38α/β MAPKi harvested at 7 DPI. Scale bar, 500 \(\upmu\)m. C,D; right Quantification of the MuSC-mediated regeneration (%YFP coverage) in the injured mini-myotube templates generated with 18M (C) or 19F (D) cell line harvested at 7 DPI or 10 DPI. Graphs display mean ± s.e.m; Unpaired two-tailed T-test with Welch’s correction was conducted for each condition. * p < 0.05, ** p < 0.001, **** p, n = 9–12 tissues from N = 3–4 independent experiments per cell line