Table 3.
Effect of age on the absolute synthesis rate of targeted articular cartilage matrix proteins.
| Protein name | Fold-change (90 wk:25 wk) | Mean difference ( ) |
95% CI of difference ( ) |
P-value | |
|---|---|---|---|---|---|
| Proteoglycans | |||||
| ACAN | 0.09 | -2.58 | [-2.88, -2.27] | <0.0001# | |
| ASPN* | 2.29 | 0.16 | [0.07, 0.25] | 0.0022# | |
| BGN* | 0.50 | -2.67 | [-3.35, -2.01] | <0.0001# | |
| DCN* | 0.65 | -36.8 | [-57.2, -9.85] | 0.0011# | |
| FMOD* | 0.27 | -1.07 | [-1.20, -0.94] | <0.0001# | |
| FN1 | 0.83 | -2.94 | [-6.65, 0.08] | 0.1129 | |
| LUM* | 0.88 | -5.85 | [-19.0, 7.25] | 0.3585 | |
| OGN* | 0.01 | -0.69 | [-0.81, -0.56] | <0.0001# | |
| PRELP | 0.38 | -11.5 | [-13.6, -9.46] | <0.0001# | |
| PRG4 | 1.18 | 3.96 | [-2.34, 10.3] | 0.2006 | |
| Collagens | |||||
| COL1A1 | 0.02 | -2.05 | [-2.23, -1.87] | <0.0001# | |
| COL2A1 | 0 | -0.053 | [-0.059, -0.045] | <0.0001# | |
| COL6A1 | 0.98 | -0.00 042 | [-0.0059, 0.0050] | 0.8726 | |
| COL6A2 | 0.51 | -0.018 | [-0.024, -0.012] | <0.0001# | |
| COL6A3 | 0.54 | -0.165 | [-0.23, -0.10] | <0.0001# | |
| COL9A1 | – | – | – | – | |
| COL11A1 | – | – | – | – | |
| COL12A1 | 0 | -0.0069 | [-0.0075, -0.0063] | <0.0001# | |
| ECM-related | |||||
| CHAD | 0.17 | -1.20 | [-1.37, -0.02] | <0.0001# | |
| CHIL3 | 0.35 | -4.01 | [-5.78, -2.29] | <0.0001# | |
| CILP | 0.35 | -1.21 | [-1.43, -1.00] | <0.0001# | |
| CLU | 0.81 | -1.96 | [-3.86, -0.06] | 0.0432 | |
| COMP | 0.26 | -40.4 | [-46.1, -34.7] | <0.0001# | |
| LMNA | 0.82 | -1.20 | [-2.78, 0.38] | 0.1279 | |
| MATN1 | – | – | – | – | |
| MATN3 | 0.38 | -1.30 | [-1.74, -0.21] | <0.0001# | |
| MFGE8 | 0.55 | -16.7 | [-20.7, -12.6] | <0.0001# | |
| SPP1 | 0 | -0.017 | [-0.019, -0.016] | <0.0001# | |
| THBS1 | 0.20 | -3.25 | [-3.72, -2.78] | <0.0001# | |
| VTN | 0.39 | -4.10 | [-5.13, -3.06] | <0.0001# |
Protein absolute synthesis was calculated by dividing protein concentration [pmol/mg total protein] by protein half-life [days]. Mean difference was calculated as 90 wk minus 25 wk values. Comparison between groups was performed using paired t-test (two-tailed) with Welch's correction.
*
Small leucine-rich proteoglycans (SLRPs).
#
P<<0.05i > following Benjamini-Hochberg FDR correction for multiple comparisons.