BT and CS inhibited the IL-32 or LPS-induced TSLP production and mRNA expression through the inhibition of caspase-1 and NF-κB activation. THP-1 cells (3 × 105) were treated with BT (100 μg/ml) and CS (0.1, 1, and 10 μg/ml) for 2 h and then stimulated with LPS (10 ng/ml, (A) or IL-32 (0.1 μg/ml, (B) for 24 h. The production of TSLP in the supernatant was measured by the ELISA method. (C and D) THP-1 cells (3 × 106) were treated with BT or CS for 5 h. The mRNA expressions of TSLP were measured by the RT-PCR method. THP-1 cells (3 × 106) were treated with BT (100 μg/ml) and CS (0.1, 1, and 10 μg/ml) for 2 h and then stimulated with IL-32 (0.1 μg/ml) or LPS (10 ng/ml) for 2 h. (E and F) Caspase-1 and NF-κB were determined by Western blot analysis. (G and H) Caspase-1 activity was determined by a colorimetric kit. *P < 0.05; significantly different from the unstimulated cells' value, **P < 0.05; significantly different from the IL-32 or LPS-stimulated cells' value. BT, BaekJeol-Tang; CS, chondroitin sulfate; ELISA, enzyme-linked immunosorbent assay; IL, interleukin; LPS, lipopolysaccharide; NF-κB, nuclear factor-κB; RT-PCR, reverse transcriptase polymerase chain reaction; TSLP, thymic stromal lymphopoietin.
Jeong et al. Arthritis Research & Therapy 2012 14:R259 doi:10.1186/ar4104