Figure 2.

Kartogenin treatment reduces IL-1β stimulation of proteoglycan release from articular cartilage explant cultures. Bovine articular cartilage disks were cultured as explants in serum free media the in the absence (−) or presence (+) of 100 µM kartogenin (KGN) for 48 hours and then treated and treated without (−) or with (+) 10 ng/mL IL-1β for 24 hours. The medium samples were collected and analyzed for sulfated glycosaminoglycans. Data from 6 replicate disks (experiment A) and from 8 replicate disks (experiment B) show that KGN treatment alone did not change the release of sulfated glycosaminoglycans from the cartilage explants while IL-1β treatment did; however, the enhanced release of sulfated glycosaminoglycans was inhibited by co-treatment with KGN and IL-1β. (A, n = 6, P = 0.060; B, n = 8, P = 0.010.)