Fig. 6

AA injection slows down cartilage degeneration in rat OA model. a Schematic of the ACLT-induced rat knee OA model. ACLT-induced rats treated with intra-articular (IA) injection of either vehicle or AA (2.5 μg/mL), and cartilage was isolated at 4 and 8 weeks. b Macroscopic appearance of cartilage from tibial plateaus of rats (n = 2 for each group). The arrow in the ACLT group at 4 weeks indicates cartilage hyperplasia, and the arrow in the ACLT group and ACLT+AA group at 8 weeks indicates eroded cartilage. c Safranin O/Fast Green stained sections of knee joints (n = 3 for each group). d Immunohistochemistry analysis of COL-II in sections of tibial plateau of knee joints (n = 3 for each group). e The macroscopic observation scores of knee joints (n = 2 for each group). f Cartilage degeneration evaluated with the Osteoarthritis Research Society International (OARSI) scoring system (n = 3 for each group). One-way ANOVA, *P < 0.05, **P < 0.01, ****P < 0.0001. Boxed regions in the bottom panels are shown in the top panels