Autophagy Protects Advanced Glycation End Product-Induced Apoptosis and Expression of MMP-3 and MMP-13 in Rat Chondrocytes

Figure 4

Autophagy plays a protective role in AGE-induced MMP-3 and MMP-13 expression in chondrocytes. (a) MMP-3 and MMP-13 protein levels were measured by Western blot assay after treatment with 100 μg/mL AGEs for 0, 3, 6, 12, and 24 h. (b, c) Protein densitometric quantification of MMP-3 and MMP-13. (d) Chondrocytes were treated with 100 μg/mL AGEs for 6 h with or without pretreatment of 3-MA (5 mM) or RA (5 μM) for 1 h. The protein levels of MMP-3 and MMP-13 are determined by Western blot analysis. (e, f) Protein densitometric quantification of MMP-3 and MMP-13. All results are the mean ± SD of three independent experiments. , , and versus the control group. and versus AGE-treated cells.

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