JScholar Publishers Water-Soluble C60-(OH)24 Fullerene Hydroxide Protects against the Catabol- ic Stress-Induce Downregulation of Chondrocyte Activity in Osteoarthritis

Recently, attention has been attracted to the roles of oxidative stress and related chondrocyte aging in the pathogen-esis of osteoarthritis (OA). To prevent the degeneration of articular cartilage in OA, we focused on water-soluble fullerene hydroxide C60(OH)24, a novel and strong free radical scavenger, as an anti-oxidative agent. Water-soluble C60(OH)24 was studied for its potential as a protective agent against catabolic stress-induced degenera-tion of articular cartilage in vitro. In the presence or absence of C60(OH)24 (1.0 nM, 10.0 nM, 100.0 nM), human chondro-cytes were incubated with IL-1 β (1.0 ng/ml). After the 24-hour incubation period, chondrocyte activity was analyzed. Results indicated that C60(OH)24 inhibited the OA-relating catabolic responses (IL-1β-induced production of carti-lage degrading enzyme, IL-1β-induced down regulation of proteoglycan production and glucose metabolism) in OA chon-drocytes. C60(OH)24 also reduced the IL-1β-induced upregulation DNA repair enzyme, apurinic/apyrimidinic endonuclease 2 (Apex 2), in OA chondrocytes. Our findings suggest that C60(OH)24 may have a potential to protect against the IL-1β-induced downregulation of chondrocyte activity in OA. These data provide a novel pathogenic mechanism linking oxidant-mediated DNA damage an