Figure 10

Possible mechanism underlying degenerative joint disease in MPS VI. As MPS VI articular chondrocytes age, they accumulate and release excess amounts of dermatan sulfate-containing glycosaminoglycans. These cells eventually undergo apoptosis, caused by either the accumulating dermatan sulfate itself or cytokine-induced NO production resulting from mechanical stress on the MPS joints. The resulting MPS articular cartilage has an abnormal matrix composition that eventually causes functional deficits of the articular surfaces.