Lutein and β-Cryptoxanthin Inhibit Inflammatory Mediators in Human Chondrosarcoma Cells Induced with IL-1β

ABSTRACT

Studies have shown that lutein (Lu) and β-cryptoxanthin (βCr) may down-regulate factors involved in inflammation associated with osteoarthritis and rheumatoid arthritis. We studied the possible protective effects of Lu and βCr in vitro against human chondrocyte dysfunction using a human chondrosarcoma cell line.

SW-1353 human chondrosarcoma cells were cultured for 24 hr in supplemented medium containing 0, 0.01, 0.1 or 1.0 μmol/L of Lu or βCr and subsequently stressed for 24 hr in the presence of 10 μg/L IL-1β. The resulting conditioned medium was analyzed for matrix-metalloproteinase-13 (MMP-13), cytokines (IL-1α, IL-2, IL-4, IL-10, IFN-γ , IL- 6, IL-8, and TNF-α), and PGE2. Nuclear extract from the harvested cells was analyzed for NFκB.

Lu (1.0 μmol/L; P<0.05) but not βCr decreased MMP-13. Both Lu (1.0 μmol/L; P<0.05) and βCr (0.1 and 0.01 μmol/L; P<0.01) inhibited PGE₂ production. All concentrations of βCr suppressed (P<0.05) IL-1α, IL-2 and IFN-γ production while Lu increased concentrations of these cytokines. Lu increased (P<0.05) while βCr decreased IL-4 and IL-10 concentrations. NFκB p50 production was suppressed (P<0.01) by both Lu and βCr, with Lu being more inhibitory.

Therefore, Lu and βCr protected against IL-1β-induced chondrocyte dysfunction by down-regulating NFκB activation and inhibiting inflammatory response, albeit through somewhat different pathways.