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Table 7 Skeletal muscle metabolic intermediate concentrations

From: Molecular alterations in skeletal muscle in rheumatoid arthritis are related to disease activity, physical inactivity, and disability

  Rheumatoid arthririts (n = 51) Controls (n = 50)
Mean SD Mean SD
Amino acids
 Glycine 1012.669 304.568 1042.875 360.089
 Alanine 2781.241 876.247 2735.464 820.802
 Serine 773.987 190.246 777.726 286.455
 Proline 502.861 179.5 528.023 222.984
 Valine 291.82 75.004 300.739 99.003
 Leucine/isoleucine 659.544 197.996 663.116 233.404
 Methionine 54.167 14.36 55.372 17.48
 Histidine 488.821 164.605 548.187 276.048
 Phenylalanine 77.739 22.414 80.155 27.759
 Tyrosine 80.962 23.249 88.815 32.052
 Aspartate/asparagine 100.518 62.088 144.672 198.704
 Glutamate/glutamine 2096.524 658.272 2359.04 878.482
 Ornithine 212.338 85.775 184.849 69.873
 Citrulline 69.446 39.718 75.05 50.441
 Arginine 431.024 182.215 394.565 149.594
Organic acids
 Lactate 22862.683 9246.29 20956.576 8926.553
 Pyruvate 1168.544* 604.675 803.474 539.098
 Succinate 48.143 35.538 41.793 29.968
 Fumarate 70.313 26.403 62.708 25.253
 Malate 521.019 205.905 476.648 198.079
 alphaKetoglutarate 144.24 143.952 113.438 118.669
 Citrate 41.677 33.591 36.853 24.096
Acylcarnitines
 Free carnitine: C0 3369.034 1006.646 3631.978 1243.598
 C2 455.175 288.39 485.702 312.966
 C3 5.206 2.024 5.019 2.018
 C4/Ci4 3.541 4.994 3.008 2.594
 C5:1 1.033 0.397 1.03 0.41
 C5 1.667 1.15 2.246 5.666
 C4OH 2.789 2.231 2.378 1.778
 C6 3.58 3.882 2.956 2.855
 C5OH 0.676 0.363 0.65 0.343
 C3DC 0.793 0.356 0.809 0.292
 C4DC/Ci4DC 2.439 1.424 2.547 1.192
 C8:1 0.531 0.328 0.532 0.252
 C8 0.942 0.904 0.826 0.694
 C5DC 1.528 1.043 1.43 0.727
 C8:1OH/C6:1 DC 0.216 0.129 0.204 0.123
 C6DC/C8OH 0.353 0.239 0.388 0.226
 C10:3 0.067 0.047 0.067 0.034
 C10:2 0.05 0.03 0.063 0.041
 C10:1 0.261 0.253 0.239 0.164
 C10 0.655 0.6 0.58 0.48
 C7DC 0.108 0.079 0.088 0.049
 C8:1 DC 0.087 0.073 0.093 0.051
 C10OH:C8DC 0.305 0.253 0.31 0.21
 C12:2 0.052 0.034 0.052 0.035
 C12:1 0.364 0.281 0.366 0.287
 C12 1.359 1.073 1.31 1.125
 C12:2OH/C10:2 DC 0.075 0.045 0.064 0.04
 C12:1OH/C10:1 DC 0.224 0.178 0.202 0.114
 C12OH/C10DC 0.441 0.472 0.417 0.382
 C14:3 0.078 0.052 0.073 0.054
 C14:2 1.126 1.025 0.902 0.83
 C14:1 2.726 2.354 2.449 2.232
 C14 4.156 3.277 3.781 3.373
 C14:3OH/C12:3 DC 0.032 0.025 0.028 0.022
 C14:2OH/C12:2 DC 0.174 0.121 0.143 0.081
 C14:1OH/C12:1 DC 0.704 0.538 0.701 0.431
 C14OH/C12DC 0.502 0.525 0.487 0.381
 C16:3 0.198 0.164 0.157 0.103
 C16:2 1.533 1.201 1.199 0.948
 C16:1 6.736 5.227 5.751 3.973
 C16 20.041 15.253 17.878 12.497
 C16:3OH/C14:3-DC 0.053 0.038 0.045 0.024
 C16:2OH/C14:2 DC 0.477 0.336 0.412 0.248
 C16:1OH/C14:1 DC 1.306 1.077 1.256 0.834
 C16OH/C14DC 1.18 1.265 1.229 1.059
 C18:3 1.463 0.982 1.354 0.925
 C18:2 20.561 15.909 17.722 13.495
 C18:1 46.521 37.117 40.451 28.311
 C18 11.278 8.401 10.817 8.203
 C18:3OH/C16:3 DC 0.186 0.158 0.168 0.101
 C18:2OH/C16:2 DC 1.357 1.235 1.323 1.177
 C18:1OH/C16:1 DC 2.683 2.889 2.844 2.749
 C18OH/C16DC 0.695 0.68 0.732 0.523
 C20:4 2.023 1.801 1.778 1.872
 C20:3 0.63 0.597 0.57 0.431
 C20:2 0.308 0.271 0.261 0.164
 C20:1 0.554 0.484 0.485 0.409
 C20 0.369 0.4 0.329 0.308
 C20:3OH/C18:3 DC 0.075 0.059 0.074 0.056
 C20:2OH/C18:2 DC 0.053 0.034 0.05 0.03
 C20:1OH/C18:1 DC 0.071 0.062 0.062 0.046
 C20OHC18DC/C22:6 0.212 0.248 0.198 0.206
 C22:5 0.264 0.299 0.247 0.277
 C22:4 0.241 0.279 0.193 0.158
 C22:3 0.064 0.057 0.056 0.044
 C22:2 0.051 0.035 0.044 0.025
 C22:1 0.069 0.05 0.065 0.038
 C22 0.059 0.049 0.062 0.046
  1. Data are shown as means and standard deviations (pmol/mg tissue). Metabolic intermediates were measured in muscle homogenates. Group comparisons between muscle from patients with rheumatoid arthritis and from controls were performed using logarithmically transformed metabolic intermediates and mixed models. Prefix C denotes acylcarnitines followed by carbon number and degree of unsaturation. Suffixes OH and DC denote hydroxyl and dicarboxyl groups, respectively. *P < 0.05 for comparison with matched controls