Melatonin Improves the Resistance of Oxidative Stress-Induced Cellular Senescence in Osteoporotic Bone Marrow Mesenchymal Stem Cells

Figure 6

Evaluation of the antisenescence properties of BMMSCs derived from melatonin-treated rats. BMMSCs were isolated from untreated and melatonin-treated (MT) sham-op or OVX rats and then exposed to H₂O₂ (100 μM) for 2 h. (a, b) Senescent cells were labeled by senescence-associated β-galactosidase (SA-β-gal) staining.  μm. (c) The cell viability of OVX BMMSCs was determined by CCK-8 assays. (d, e) The protein levels of SIRT1, P16, P21, and P53 were determined using Western blot assays. (f) After exposure to H₂O₂, BMMSCs were induced toward osteogenic differentiation. Matrix mineralization was determined by Alizarin Red S (ARS) staining.  μm. (g) The stained mineral layers were quantified. The values were normalized to those of the sham group. (h) The mRNA levels of osteoblast-specific marker genes, including Runx2, Sp7, and Bglap were quantified using qRT-PCR with Gapdh serving as the internal reference gene for normalization. Values are presented as the of six independent experiments () in SA-β-gal staining, eight independent experiments () in cell viability assays, four independent experiments () in ARS assays, three independent experiments () in Western blot assays, and four independent experiments () in qRT-PCR experiments. Statistically significant differences are indicated by or between the indicated groups; ^# or ^## versus the sham group.

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