Fig. 2

Metformin attenuates cartilage degeneration in the destabilization of the medial meniscus mice model. A Safranin O-fast green staining with arrows indicating cartilage proteoglycan loss (scale bar, 100 µm and 50 µm) and E OARSI score. B H&E staining (scale bar, 100 µm), black arrows indicate HC thickness and white arrows indicate CC thickness, and thickness of F HC and G CC. C MMP 13 and D Col II immunohistochemical staining (scale bar, 100 µm), arrows indicate positive cells, and H MMP13 and I Col II positive cell proportions. One-way ANOVA and Tukey’s multiple comparison tests were used to compare the data. Nonparametric data (OARSI scores) were analyzed using the Kruskal–Wallis H test followed by Dunn’s test. ***P < 0.001