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

Figure 1

KLF2 expression is suppressed during osteoarthritis pathogenesis. (a) Microarray analysis of KLF2, MMP13, and COL2A1 expression in OA cartilage () and normal cartilage () based on GSE114007. (b) Real-time PCR analysis was used to assess the mRNA levels of KLF2 in normal and OA cartilage from human patients ( per group). (c) Representative images of safranin O/fast green staining and immunohistochemical staining with antibodies against KLF2 in normal and OA cartilage from human knee joints ( per group). The scale bar represents 200 μm. The right panels show the quantification of KLF2 immunohistochemical staining. (d) Representative images of immunohistochemical staining with antibodies against MMP13 and COL2A1 in normal and OA cartilage from human knee joints ( per group). The scale bar represents 200 μm. The right panels show the quantification of the immunohistochemical staining of MMP13 and COL2A1. (e) RNA was isolated from smooth and damaged regions of OA cartilage from the same patient (), and the levels of KLF2 mRNA were evaluated by real-time PCR. (f) Representative X-rays of different stages of OA graded by the Kellgren-Lawrence scale system. (g) RNA was isolated from grade 1-4 OA patients, and KLF2 mRNA expression was evaluated by real-time PCR ( per group). All data are expressed as the . and .

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