Research Paper Volume 11, Issue 22 pp 10513—10531

Astaxanthin protects against osteoarthritis via Nrf2: a guardian of cartilage homeostasis

Figure 3. Effects of Ast on OA chondrocytes. Chondrocytes were pretreated with or without Ast (5, 10, and 20 μM) for 2 h and then exposed to IL-1β (5 ng/ml) for 24 h. Then, (AC) the expression of Collagen II, ADAMTS5, MMP3, and MMP13 was examined by RT-PCR and western blotting and quantified. Chondrocytes were treated with the vehicle or with increasing concentrations of Ast for 2 h followed by (5 ng/ml) TNF-α stimulation. (D, E) The expression of Collagen II, ADAMTS5, MMP3, and MMP13 were determined by western blotting and quantified. After the cells were treated with the vehicle or Ast (5, 10, and 20 μM) for 2 h, and stimulated with 100 μM TBHP, (F, G) the expression of Collagen II, ADAMTS5, and MMP13 was investigated by western blotting and quantified. The data are presented as dot plots from three independent experiments. Significant differences among different groups are indicated as **p<0.01 vs. control; ***p<0.001 vs. control; ****p<0.0001 vs. control. #p < 0.05 vs. IL-1β or TNF-α or TBHP group; ##p < 0.01 vs. IL-1β or TNF-α or TBHP group; ###p < 0.001 vs. IL-1β or TNF-α or TBHP group; ####p < 0.0001 vs. IL-1β or TNF-α or TBHP group.