Fig. 4.

mTOR silencing restored the 29-kDa FN-f-suppressed LC3-II level and HMGB1 in primary chondrocytes. (A) Chondrocytes were transfected with control siRNA (si-con) and small interfering mTOR RNA (si-mTOR); 48 h later chondrocytes were stimulated with 29-kDa FN-f for 24 h. The protein levels were measured using western blot analysis. β-actin served as loading controls. (B) Schematic diagram of mechanism leading to 29-kDa FN-f–suppressed HMGB1-dependent autophagy pathway in primary chondrocytes.