Aging Induced p53/p21 in Genioglossus Muscle Stem Cells and Enhanced Upper Airway Injury

Figure 5

Hypoxia enhanced the inhibitory effect of aging on GG MuSC proliferation. (a) The GG MuSCs from 1-month-old and 12-month-old were treated with 0 μM and 200 μM CoCl₂ for 3 days. The cell number was decreased to approximately 40% that of untreated cells. (b) Immunofluorescence staining for Pax7 and HIF-1α in MuSCs treated with or without CoCl₂ for 3 days. (c) Ki67-positive cells in GG MuSCs under normoxia and hypoxia. Ki67 was observed by immunofluorescence staining. (d) The control experiment of IF. Statistical significance is marked as follows: represents difference between same CoCl₂ and 1-month-old vs. 12-month-old; , , and . @ represents the difference in 1-month-old and 0 vs. 200 μM CoCl₂; ^@ and ^@@. # represents the difference in 12-month-old and 0 vs. 200 μM CoCl₂; ^#, ^##, and ^###. Scale bars are 100 μm.

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