Figure 7. Knockdown of hsa_circ_0032131 attenuated OA symptoms in vivo. (A) Rats were sacrificed and cartilage tissues were collected. Next, OA symptoms in the cartilage tissues were observed by hematoxylin and eosin (H&E) and representative safranin O staining, and by examining the cartilage subchondral bone. (B) Subchondral bone thickness was calculated. (C) Synovitis scores of cartilage tissues in rats were evaluated. (D) The Osteoarthritis Research Society International (OARSI) scores of cartilage tissues were evaluated. The levels of (E) IL-1β and (F) TNF-α in the plasma of rats were detected by enzyme-linked immunosorbent assay (ELISA). (G) The level of hsa_circ_0032131 in rat tissues was measured by RT-qPCR. **p < 0.01 compared with the control. ##p < 0.01 compared with OA.