AIMS: Accumulation of advanced glycation end products (AGEs) plays a pivotal role in the mechanism by which aging contributes to osteoarthritis (OA). In the present study, we examined the effect of curcumin, a pharmacologically safe phytochemical agent, on AGE-induced tumor necrosis factor-α (TNF-α) and matrix metalloproteinase-13 (MMP-13) in rabbit chondrocytes. METHODS: Chondrocytes were derived from rabbit articular cartilage by enzymatic digestion. TNF-α and MMP-13 mRNA was monitored by RT-PCR. TNF-α protein was determined using cytokine-specific ELISA. The reactive oxygen species was determined by the fluorescent probe 29,79-dichlorofluorescein diacetate. The phosphorylation and nuclear translocation of the nuclear factor-ĸB (NF-ĸB) system were studied by Western blot and immunofluorescence respectively. RESULTS: Curcumin significantly decreased AGE-stimulated TNF-α and MMP-13 mRNA and suppressed the NF-ĸB activation via inhibition of ĸBα (I-ĸBα) phosphorylation, I-ĸBα degradation and p65 nuclear translocation. CONCLUSIONS: These novel pharmacological actions of curcumin on AGE-stimulated chondrocytes provide new suggestions that curcumin has nutritional potential as a naturally occurring anti-inflammatory agent for treating OA.
AIMS: Accumulation of advanced glycation end products (AGEs) plays a pivotal role in the mechanism by which aging contributes to osteoarthritis (OA). In the present study, we examined the effect of curcumin, a pharmacologically safe phytochemical agent, on AGE-induced tumor necrosis factor-α (TNF-α) and matrix metalloproteinase-13 (MMP-13) in rabbit chondrocytes. METHODS: Chondrocytes were derived from rabbit articular cartilage by enzymatic digestion. TNF-α and MMP-13 mRNA was monitored by RT-PCR. TNF-α protein was determined using cytokine-specific ELISA. The reactive oxygen species was determined by the fluorescent probe 29,79-dichlorofluorescein diacetate. The phosphorylation and nuclear translocation of the nuclear factor-ĸB (NF-ĸB) system were studied by Western blot and immunofluorescence respectively. RESULTS:Curcumin significantly decreased AGE-stimulated TNF-α and MMP-13 mRNA and suppressed the NF-ĸB activation via inhibition of ĸBα (I-ĸBα) phosphorylation, I-ĸBα degradation and p65 nuclear translocation. CONCLUSIONS: These novel pharmacological actions of curcumin on AGE-stimulated chondrocytes provide new suggestions that curcumin has nutritional potential as a naturally occurring anti-inflammatory agent for treating OA.