Figure 6.

Catabolic function elicits a dimorphic response. Chondrocytes were treated with 10 ng/ml IL-1β for 24 hours to provoke an inflammatory response and activate the catabolic function. No differences were detected in the expression of COL2A1, ACAN, SOX9 (A-C), COL10A1, and COL11A (D-E). COL6A1 decreased similarly for males and females (F), but COL9A1 and DCN decreased, resulting in the same trend observed for basal conditions (G-H). No dimorphism was found for HSPG2 (I). All proteases tested increased with treatment (J-O), but dimorphism was observed only in ADAMTS4 and MMP1. No significant differences were detected in TIMP1 and TIMP2 expression (P-Q). The pro-inflammatory cytokines IL-1β and IL-6 increased with treatment; however, no dimorphism was detected (R-S). Data are presented as mean ± SD of relative quantity to normalizer (geometric mean of 18S and GAPDH). Cells from 6♂ + 6♀ were used in passage 0. MMP = metalloprotease; ADAMTS = a disintegrin and metalloproteinase with thrombospondin motifs; DCN = decorin; TIMP = tissue inhibitor of metalloproteases; ACAN = agreccan; COL = collagen; SOX9 = SRY (sex determining region Y)-Box 9; HSPG2 = heparan sulfate proteoglycan 2 (perlecan); GAPDH = glyceraldehyde-3-phosphate dehydrogenase.