Figure 1: Satellite cell myogenic potential and muscle regeneration by RSV in STZ-treated control mice. (A) Satellite cells were prepared from tibialis anterior (TA) and gastrocnemius (Gastroc) muscle of control, STZ-treated mice (STZ), and RSV-treated STZ mice (STZ/RSV) at 3 days post-injury (DPI), cultured in growth medium for 24 h and then switched to differentiation medium for 48 h. Formation of de-novo eMyHC+ myotubes (red) and BrdU+ nuclei (green) were assayed by immunofluorescence. Hoechst (blue) labels all nuclei. Scale bar, 100 μm. (B) The percent of nuclei in eMyHC+ myotubes to total nuclei (black bars), the percent of BrdU+ nuclei in myotubesto total nuclei (white bars), and the percent of eMyHC+ myotubes with more than two nuclei to total nuclei (gray bars)were quantified. n=3 with more than three independent experiments; P<0.001 control as compared to STZ-treated mice, and P<0.01 STZ/RSV as compared to STZtreated mice. Data are mean ± SD. (C) Assessment of muscle regeneration in vivo was performed by hematoxylin and eosin (H&E) histological analysis and by immunodetection of de-novo eMyHC+ myofibers (Red) in 10 μm cryosections of TA and Gastroc muscles that were isolated at 5 DPI. Scale bar, 100 μm. (D) Numbers of de-novo myofibers per mm2 of injured muscle (covering the entire injury site) were quantified. n=3 with more than three independent experiments; P<0.01 control as compared to STZ-treated mice, and P<0.05 STZ/RSV as compared to STZ treated mice. Data are mean ± SD.