Fig. 1

Effect of 4-methylumbelliferone (4-MU) on the anterior cruciate ligament (ACL)-derived cells stimulated with interleukin (IL)-1β. ACL-derived cells were treated with 0 to 10 ng/mL of IL-1β for 12 h. (A) To examine cytotoxicity of 4-MU, ACL-derived cells were treated with different concentrations of 4-MU for 12 h and cytotoxicity LDH Assay was performed (n = 3). (B) qRT-PCR was performed to determine the mRNA expression of matrix metalloproteinase 1 (MMP-1), MMP-3, and IL-6 (n = 3). ACL-derived cells were treated with or without 0.1 ng/mL IL-1β in the presence or absence of different concentrations of 4-MU for 12 h. (C) qRT-PCR (n = 6) and (D) capillary western immunoassay (n = 3) were performed to determine the MMP-1, MMP-3, and IL-6 mRNA and MMP-1, MMP-3, and IL-6 protein expression, respectively. (E) Statistical quantification of each protein expression. The values are presented as mean ± SD. *p < 0.05; **p < 0.01. n.s., not significant