Fig. 2.

Exosomes attenuated IL-1β-induced downregulation of anabolic markers and upregulation of catabolic markers in cartilage degradation. a mRNA levels of MMP13, ADAMTS5, COL2A1, and ACAN were determined by RT-PCR. b Western blot analysis of protein levels of COL2A1 and MMP13. c Immunofluorescence staining of COL2A1 and MMP13. Rat chondrocytes were seeded at a density of 1 × 10⁴ cells/well in the glass bottom culture dishes. Five fields were randomly selected from each sample for quantification. All experiments were repeated independently at least three biological replicates. Scale bar = 50 μm. *< 0.05, **< 0.01, ***< 0.001, compared with the control group. ^#< 0.05, ^##< 0.01, ^###< 0.001, compared with the IL-1β group