miR-142-5p as a CXCR4-Targeted MicroRNA Attenuates SDF-1-Induced Chondrocyte Apoptosis and Cartilage Degradation via Inactivating MAPK Signaling Pathway

Figure 5

miR-142-5p regulated MAPK signaling pathways in SDF-1-induced chondrocytes. (a–e) Primary human OA chondrocytes were transfected with the indicated miRNA mimics and plasmids. At 48 h after transfection, cells were then treated with SDF-1 (100 ng/ml) for another 24 h. The protein expressions of key molecules in the MAPK (JNK, p38, ERK, p-JNK, p-p38, and p-ERK) signaling pathway were then measured by Western blot assays. Representative bands images of molecules in the MAPK (a) signaling pathways are shown. The relative bands intensity of CXCR4 (b) and the ratios of p-p38/p38 (c), p-ERK/ERK (d), and p-JNK/JNK (e) were summarized. Data are presented as the mean ± SEM (n = 3). ; . miRNAs, microRNAs; SDF-1, stromal cell-derived factor 1; NC, negative control; ERK, extracellular regulated protein kinases; p-ERK, phosphorylated extracellular regulated protein kinases; JNK, c-Jun N-terminal kinase; p-JNK, phosphorylated c-Jun N-terminal kinase; Gapdh, glyceraldehyde‐3‐phosphate dehydrogenase.

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