(a) Scheme illustration of NIR light-modulated cellular behaviors of muscle satellite cells in vivo using NIR-DA system. (b) The procedure for acute muscle injury animal model. (c) The photothermal effect of NIR light in living mice. Infrared thermal imaging of the mouse with or without the injection of AuNRs@DAMET (1.0 nM) were irradiated under 808 nm laser (1.00 W/cm2) for different periods. (d) The injured mice were injected with AuNRs@DAMET (1.0 nM) and irradiated with or without NIR light. Left: immunofluorescent analysis of p-MET in the sections from injured mice at 0.5 h post the injury, scale bar indicates 50 μm; Middle: immunofluorescence analysis of Pax7, Ki67 and MHC protein in the sections from the injured mice at 3 days post the injury; Right: histology by H&E staining of the sections from the injured mice at 3 days post the injury, scale bar indicates 500 μm. Quantification of average fluorescence intensity per cell of p-MET (e), Pax7 (f), Ki67(g), and MHC (h) at randomly selected high-power field (HPF) in the section from injured mice. Data are presented as mean ± SD (n = 5), and the statistical significance was determined using Student’s non-paired t-test, *p<0.05.