Figure 2.

Collagen type II protects human NP cells from IL-1β-induced metabolic disturbance. Human NP cells were treated with or without vehicle (0.05 M acetic acid), 10 ng/ml IL-1β and/or 100 µg/ml purified collagen type II for 48 h, as indicated. (A) mRNA and (B) protein expression levels of MMP13, ADAMTS4, ACAN, and COL2A1 were detected by reverse transcription-quantitative polymerase chain reaction and western blotting, respectively. Data are presented as means ± standard deviation of three independent experiments. *P<0.05, with comparisons indicated by brackets. NP, nucleus pulposus; IL, interleukin; MMP13, matrix metalloproteinase 13; ADAMTS4, a disintegrin and metalloproteinase with thrombospondin motifs 4; ACAN, aggrecan; COL2A1, collagen type II α 1.