Fig 2: Effect of AWE on the expression of Type II collagen, MMP-1, and MMP-13 in the SW1353 cell. (A) The protein expression levels of COL2A1, MMP-1, and MMP-13 were analyzed using Western blot, with β-actin serving as internal reference. (B) Quantification analysis. Data represent the mean ± SEM. ### p < 0.001 vs. untreated control. * p < 0.05; ** p < 0.01; *** p < 0.001 vs. IL-1β -induced group.

Fig 3: BAPTA-AM administration alleviated DMM-induced OA. The mice were divided into DMM, DMM + BAPTA-AM (1.5 μg/kg), and DMM + BAPTA-AM (15 μg/kg) groups. After a week of DMM surgery, 10 μl of BAPTA-AM solution or PBS was intra-articularly injected weekly. Images of Safranin O/Fast green staining (A) and (B) H&E staining (Linear scale = 200 µm). (C) The OARSI scores analysis for cartilage degeneration (n = 10). (D) 3D reconstruction images and the tibial plateau transverse sectional images (Linear scale = 1 mm). (E) Quantitation of maximum osteophyte outgrowth (n = 10). (F) H&E staining of synovium and (G) the quantitative analysis of synovitis scores, the black arrow indicates synovial lining cells (Linear scale = 200 µm, n = 10). (H) IHC images (Linear scale = 100 µm) and (I) quantitative analysis of Aggrecan, COL2A1, MMP13, COX2, ADAMTS5, and iNOS (n = 10). (J) The graphic illustration of this study. Data are mean ± SEM. p values are from the Kruskal-Wallis test followed by Dunn’s post hoc test (C, I), and the one-way ANOVA test followed by Tukey’s post hoc test (E, G).

Fig 4: The levels of TRPM2 expression in OA cartilage and primary murine chondrocytes. The volcano plot analysis (A), KEGG analysis (B), and heat map analysis (C) were conducted to compare the Ctrl and IL-1β-treated groups. The concentration of IL-1β used in this study was 5 ng/ml. (D) H&E and IHC staining of TRPM2 in the cartilage of the OA group and control group (linear scales: 400 μm for H&E staining and 200 μm for IHC staining). (E) H&E and IHC staining of TRPM2 in murine cartilage from the Sham and DMM group (linear scales: 200 μm for H&E staining and 100 μm for IHC staining). (F) Quantitative analysis of TRPM2-positive chondrocytes in murine cartilage (n = 10). (G) Quantitative IHC analysis of TRPM2-positive chondrocytes within the human cartilage (Ctrl, n = 7; OA, n = 12). (H) RT-qPCR analyzed the mRNA levels of Trpm2 in IL-1β-induced chondrocytes. (I) The TRPM2 expression in IL-1β-induced chondrocytes and (J) statistical protein expression analysis. (K) IF staining results of TRPM2 expression and distribution in IL-1β-induced chondrocytes (linear scale: 20 µm). Data are presented as the mean ± SEM, and p values are from two-tailed unpaired t-tests (F, G, H, J).