Figure 1

Ferroptosis occurs in OA cartilage in a region-specific manner. (A) Representative immunohistochemical (IHC) staining of NC (Negative Control), GPX4, ACSL4, MMP13, and COL2A1 in paired intact and damaged human OA cartilages. Scale bars: 100 μm (top) and 20 μm (bottom). (B) Quantification of immunohistochemical analysis (n = 3). (C) RT-qPCR was used to detect the mRNA expression of MMP13, COL2A1, GPX4, ACSL4 in human OA cartilage (n = 3). (D) Representative immunofluorescence staining and quantification analysis of GPX4 in human OA cartilage (n = 3). Scale bar: 50 μm. (E) Representative immunofluorescence analysis of ACSL4 in human OA cartilage (n = 3). Scale bar: 50 μm. (F) JC-1 staining was performed to monitor mitochondrial membrane potential (Δψm). The ratio of the red/green fluorescence indicated the degrees of mitochondrial damage (n = 3). Scale bar: 50 μm. Data are expressed as means + SD. For all experiments p-values calculated by unpaired two-tailed Student’s t test, p < 0.05, a statistically significant difference.