KLF2 Protects against Osteoarthritis by Repressing Oxidative Response through Activation of Nrf2/ARE Signaling In Vitro and In Vivo

Figure 5

KLF2 protects against MIA-induced osteoarthritis in vivo. (a) Schematic depiction of the time of treatment. (b) Rats subjected to IA injection with sterile saline or MIA were IA-injected with Ad-C as a control or Ad-KLF2 to overexpress KLF2 in cartilage tissues (per group). Cartilage destruction was determined by safranin O staining and evaluated by OARSI grade. The scale bar represents 200 μm. (c) Detection and quantitation of apoptotic chondrocytes in cartilage by TUNEL staining. The scale bar represents 100 μm. (d) Expression of KLF2 and MMP13 was evaluated by immunohistochemical staining. The scale bar represents 50 μm. (e) Quantification of the immunohistochemical staining of KLF2 and MMP13. (f) Expression of Nrf2 was evaluated by immunohistochemical staining. Black arrowheads indicate the cells with markedly increased expression levels of nuclear Nrf2. The scale bar represents 10 μm. (g) Rats subjected to IA injection with MIA were IA-injected with Ad-C as a control or Ad-KLF2 to overexpress KLF2 in cartilage tissues with or without IA injection of ML385 ( per group). Detection and quantitation of apoptotic chondrocytes in cartilage by TUNEL staining. The scale bar represents 100 μm. (h) Expression of MMP13 was evaluated by immunohistochemical staining. The scale bar represents 50 μm. All data are expressed as the . , , and .

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