Simvastatin Impairs the Inflammatory and Repair Phases of the Postinjury Skeletal Muscle Regeneration

Figure 4

Effect of SIM on the repair phase of the postinjury skeletal muscle regeneration. To assess this effect, the mean numbers of muscle precursor cells (MPCs) (a), myotubes (b), and young myofibres (c) were evaluated in the BPVC-injured muscles of nontreated (control) and SIM-treated animals. The results represent the mean scores (±SDs) from six sites of muscle injury derived from three animals (two independent muscle injuries per single animal) per group per day. The P values (P < 0.05, P < 0.01, and P < 0.001) indicate the significance of the differences between the groups at the same time point. Representative immunohistochemistry of the myofibre regeneration sites after injury. Day 2: markedly numerous MyoD1-positive MPCs were detected in the control group, and numerous MyoD1-positive MPCs were found in the SIM-treated group. Day 4: numerous desmin-positive myotubes and not numerous young myofibres were found in the control group, and numerous desmin-positive MPCs and not numerous myotubes were detected in the SIM-treated group. Day 10: numerous desmin-positive young myofibres were observed in the control group. Not numerous desmin-positive myotubes and numerous young myofibres were found in the SIM-treated group. All sections were counterstained with haematoxylin (d).

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