Figure 4.

CL82198 prevents and decelerates MLI-induced osteoarthritis progression. Meniscal-ligamentous injury (MLI) and sham surgeries were performed on 10-week-old wild type mice. CL82198 was administered to wild type mice beginning one day after surgery by intraperitoneal injection every other day for 12 weeks at doses of 10 mg/kg body weight. Normal saline was used as a vehicle control. (A) Safranin O/Fast green staining was performed to assess proteoglycan content. Proteoglycan loss was reduced following CL82198 treatment. (B) Immunohistochemistry (IHC) of type II collagen (Col2) was performed to assess its protein level. Col2 loss was reduced following CL82198 treatment. (C) IHC of ColX was performed to assess its protein level. Type X collagen (ColX) induction was reduced following CL82198 treatment. (D) Terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) staining (in green) and 4',6-diamidino-2-phenylindole (DAPI) nuclear counterstaining (in blue) were performed to assess chondrocyte apoptosis. Chondrocyte apoptosis was reduced following CL82198 treatment. (E) Quantification of TUNEL staining positive cells was performed to assess chondrocyte apoptosis.