Figure 7.

In Vivo APLN, OSM, and POSTN Loss-of-Function Experiments during Skeletal Muscle Regeneration

Tibialis anterior muscles were injected with cardiotoxin. APLN receptor inhibitor (16 μM) and anti-OSM blocking antibodies (5 μg) were injected intramuscularly at days 2 and 3 post injury, while anti-POSTN blocking antibodies (5 μg) were injected intramuscularly at days 3 and 4 post injury. Muscles were recovered at day 8. The following criteria were evaluated: (A) number of myogenin^pos cells/mm² (in pictures myogenin is green); (B) number of nuclei/fiber (in pictures laminin is green); (C) number of embyronic myosin heavy chain (MyH3)^pos fibers (in pictures MyH3 is red); (D) number of Pax7^pos (SCs)/fiber (in pictures Pax7 is green [arrowheads] and laminin is red); (E) cross-sectional area (CSA) of the regenerating myofibers (H&E staining); (F) number of vessels/myofiber (in pictures CD31 is red and laminin is green). Blue, Hoechst. Bars, 50 μm. Mann-Whitney test was performed versus PBS for Ab-OSM and Ab-POSTN and versus PBS-DMSO for Inh-APLN: ^∗p < 0.05; ^∗∗p < 0.01; ^∗∗∗p < 0.001. Results are means ± SEM of six independent experiments.