Samples were analyzed immediately after the final loading cycle in each group for mRNA expression of SOX9 (A), ACAN (B), and COL2A1 (C), calculated as fold change over free-swelling controls, normalized to GAPDH. Data are shown as mean ± s.d. with individual data points. ANOVA with Tukey’s post-hoc tests were used to determine significance (* p < 0.05, ** p < 0.01). Immunohistochemistry for Col2a1 (D) with hematoxylin counterstain (scale bar = 100 μm). N = 4 per group.