Figure 2

Real-time reverse transcription-polymerase chain reaction gene expression profile. The messenger RNA (mRNA) expression of target gene normalized to glyceraldehyde 3-phosphate dehydrogenase (GAPDH) is represented by fold change in the loaded relative to unloaded disc (control value = 1). *P < 0.05 when compared between loaded and unloaded conditions. ^†P < 0.05 when compared between different time points. (a) Relative mRNA expression at 0, 7, 28, and 56 days of: catabolic matrix metalloproteinase (MMP)-1a = 0.9, 1.6, 3.6, 6.1, respectively; MMP-2 = 1.2, 0.8, 3.4, 10.8, respectively; MMP-3 = 1.0, 5.0, 6.0, 9.8, respectively; MMP-7 = 1.0, 1.4, 1.9, 2.0, respectively; MMP-9 = 1.1, 1.3, 1.5, 1.5, respectively; MMP-13 = 1.0, 1.3, 1.5, 1.4, respectively; a disintegrin and metalloproteinase with thrombospondin motifs (ADAMTS)-4 = 1.0, 1.6, 1.9, 1.9, respectively; ADAMTS-5 = 1.0, 1.1, 1.1, 1.1, respectively. (b) Relative mRNA expression at 0, 7, 28, and 56 days of: anti-catabolic tissue inhibitor of metalloproteinases (TIMP)-1 = 1.0, 1.2, 1.4, 1.4, respectively; TIMP-2 = 0.9, 0.5, 1.2, 1.4, respectively; TIMP-3 = 1.0, 0.6, 0.7, 0.8, respectively. (c) Relative mRNA expression at 0, 7, 28, and 56 days of: extracellular matrix aggrecan-1 = 1.0, 0.3, 0.3, 0.5, respectively; collagen type 1-α1 = 0.9, 0.8, 1.6, 3.0, respectively; collagen type 2-α1 = 0.9, 0.6, 0.3, 0.2, respectively. (d) Relative mRNA expression at 0, 7, 28, and 56 days of: pro-inflammatory cytokine tumor necrosis factor (TNF)-α = 1.0, 1.9, 2.2, 2.0, respectively; interleukin (IL)-1α = 1.0, 0.7, 0.8, 0.9, respectively; IL-1β = 1.1, 1.1, 1.1, 1.2, respectively; IL-6 = 0.9, 1.0, 1.2, 1.2, respectively.