Adipose-Derived Stem Cells Cocultured with Chondrocytes Promote the Proliferation of Chondrocytes

Figure 6

Mechanisms of promoting effect of ADSCs on chondrocytes investigated by western blot ((a), (b), (e), and (f)), real-time PCR ((c),(g)), and ELISA kit (d). Chondrocytes were cultured in control medium (chondrocytes), ADSCs cocultured system (coculture), TGF-β1-containing medium (TGF-β1), and ADSCs cocultured system plus TGF-β1 inhibitor (coculture + in) for 5 days. Both western blot ((a), (b), (e), and (f)) and real-time PCR ((c), (g)) results indicated that TGF-β1 level in chondrocytes either cocultured with ADSCs or cultured with TGF-β1-containing medium was upregulated. Furthermore, chondrocytes produced more the following proteins and genes including SOX-9, collagen type II (α1), and PGC-1α when they were cultured with either TGF-β1-containing medium or ADSCs cocultured system. In addition, the production of glycosaminoglycan (GAG) in chondrocytes cocultured with ADSCs was also increased. However, after adding TGF-β1 inhibitor to ADSCs cocultured system, the production of GAG in chondrocytes was decreased (d). Furthermore, all the above-mentioned proteins and genes were decreased in chondrocytes cultured with ADSCs plus TGF-β1 inhibitor ((e), (f) and (g)). Data are shown as mean ± SEM. versus chondrocytes group.

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