Fig. 1.

Ferroptosis and TRPM7 in chondrocytes are tightly associated with the progression of RA. (A) Genome-wide RNA-Seq data from GSE10024 and GSE12860 (Ctrl = 4, RA = 4). (B) Gene set enrichment analysis (GSEA) and (C) heatmap analysis showing the profile of ferroptosis markers in the RA versus Ctrl group. (D) Venn diagram showing the union of two clusters (GSE10024 and GSE12860). (E) Canonical pathway analysis of GSE10024 and GSE12860. (F) Representative safranin O/fast green staining, toluidine blue staining and TEM images of human normal and RA cartilages. Orange triangles indicate mitochondria. (G) IHC staining for TRPM7, NOX4 and ACSL4 on undamaged and RA cartilages. (H) The expression level of TRPM7 and ferroptosis-related proteins GPX4, ACSL4 and NOX4 in human normal and RA cartilages were determined by Western blot analysis (Normal = 5, RA = 7). Data are means ± SEM. *P < 0.05, **P < 0.01. (I) Representative H&E staining, TEM images of cartilages from normal and AA rats (n = 6 rats). Orange triangles indicate mitochondria. (J) IHC staining for TRPM7, GPX4, COX2 and NOX4 on cartilages from normal and AA rats (n = 6 rats). (For interpretation of the references to colour in this figure legend, the reader is referred to the Web version of this article.)