Vitamin C Treatment Rescues Prelamin A-Induced Premature Senescence of Subchondral Bone Mesenchymal Stem Cells

Figure 5

VC alleviated premature senescence in MSC/PLA. Representative images (a) and quantification (b) of SA-β-Gal-positive cells in MSC/PLA treated with different concentrations of VC. Data are represented as , , , , . The significant differences between means were calculated by ANOVA. Scale bar: 100 μm. (c) Immunoblots demonstrated the significant decreased prelamin A in protein level after VC treatment. (d) The decrease in expression of TNFα and IL1β in mRNA level compared MSC/PLA with or without VC treatment (). (e) Representative confocal images of the expression of Ki67 in MSC/PLA treated with or without VC treatment. (f) VC restored decreased expression of TERF1, POT1, and RAP1A in MSC/PLA (). (g) Quantitative RT-PCR illuminated the increase in expression of collagen I and collagen III in MSC/PLA treated with VC (, ). (h) P21 downregulated after VC treatment in MSC/PLA (). (i) VC rescued the expression of CDK2 and CCNE at the mRNA level and partly ameliorated cell cycle arrest in MSC/PLA (, ). (j) Quantitative RT-PCR illuminated decreased levels of the apoptotic Bcl2/BAX ratio after VC treatment (). (k) Representative pictures of limb survival of PBS, MSC/GFP, MSC/PLA, and MSC/PLA+VC groups. (l) Representative Laser-Doppler flow images (left) postischemia at days 0, 7, 14, and 21 of PBS, MSC/GFP, MSC/PLA, and MSC/PLA+VC. Quantitative evaluation of blood flow (right) expressed as a ratio of ischemic to normal limb demonstrated significantly enhanced limb blood perfusion in MSC/GFP compared with PBS and MSC/PLA (MSC/GFP vs. PBS, , ; MSC/PLA vs. PBS, ^&; MSC/GFP vs. MSC/PLA, ^$; MSC/PLA vs. MSC/PLA+VC ^~; MSC/PLA+VC vs. PBS, ^#).

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