Research Paper Volume 12, Issue 20 pp 20226—20234

Aerobic exercise induces tumor suppressor p16INK4a expression of endothelial progenitor cells in human skeletal muscle

Figure 2. Massive increases of senescent endothelial progenitor cells in human skeletal muscle 3 h after aerobic exercise (70% V̇O2max). Approximately 21-fold increases in senescent endothelial progenitor cells occurred 3 h after 1-h cycling exercise (70% V̇O2max), while Rg1 supplementation advances the increase immediately after exercise (~3-fold) and decline to baseline 3 h after exercise (A, C). Total endothelial progenitor cells (CD34+) surrounding myofibers were unaltered after exercise for both trials (B, D). Approximately 60% of elevated senescent endothelial progenitor cells was contributed by endothelial progenitor cells (p16INK4a+ / CD34+) (E, G), while the rest of 40% was contributed by infiltrated nucleated cells (p16INK4a+ / CD34-) (F, H). Scale bar = 30 μm. Data are expressed as mean and SEM. * Significant difference against Pre (Baseline), P < 0.01; † Significant difference against Placebo, P < 0.01. Abbreviation: PLA, Placebo.