Fig 1: Rehmannia delays OA degeneration. Representative images of H&E, safranin O-fast green staining, and Col-II immunohistochemistry (A). Original magnification × 100. Quantitative analysis of the relative protein expression of aggrecan (B), MMP-3 (C), MMP-9 (D), MMP-13 (E), ADAMTS-4 (F), and ADAMTS-5 (G) in cartilage. GAPDH was used as a loading control. Values indicate mean ± standard deviation (SD), where SD is shown as vertical bars. Data represent the mean of three independent experiments. *P < 0.05 and **P < 0.01 compared with the OA group.