Fig. 8

A potential molecular mechanism underlying BIG-induced inhibition of apoptosis and autophagy in chondrocytes in OA. Chondrocytes secrete inflammatory factors, including IL-1β, IL-6, TNF-α, and AGEs, which inhibit the expression of CH25H and CYP7B1 and cause dysregulation of cholesterol metabolism. However, BIG binds to the active domain of c-MYC, and activated c-MYC stimulates CH25H as well as increased CYP7B1 expression, which regulates cholesterol metabolism and promotes the cell cycle of chondrocytes, thus inhibiting chondrocyte apoptosis and autophagy