Figure 8.

Low-dose efficacy of nanodrug on protein expression of cytokines and MMPs in TNF-α-stimulated FLS.

Notes: (A–C) FLS cells were pretreated with 0.25 μg/mL DEX-PEG-coated CNT (PEG-coated CNT: 1 μg/mL, DEX: 1 μg/mL) for 2 h, and then stimulated with TNF-α (20 ng/mL) for 24 h. The levels of TNF-α, IL-1β, and IL-6 were measured in the culture medium by ELISA. All data represent mean ± SEM. *P<0.05, **P<0.05, and ***P<0.01 compared to the TNF-α-stimulated positive control. The data are presented as mean ± SEM (n=3). (D) Changes in protein levels of MMP-1 and MMP-3 were analyzed by Western blot analysis. Cells were pretreated with DEX (1 μg/mL), PEG-coated CNT (0.04 μg/mL), and DEX-PEG-coated CNT (0.25 μg/mL) 20 min before stimulation with TNF-α (20 ng/mL) for 24 min. β-actin was used as a loading control.

Abbreviations: CNT, carbon nanotube; DEX, dexamethasone; ELISA, enzyme-linked immunosorbent assay; FLS, fibroblast-like synoviocytes; IL-β, interleukin-β; IL-6, interleukin-6; MMP, matrix metalloproteinase; PEG, polyethylene-glycol; SEM, standard error of the mean; TNF-α, tumor necrosis factor-α.