TABLE 2.
13C enrichments (mole percent enrichment) of intracellular amino acids in normal and T2D human islets
Data are presented as mean ± S.E. G 5 and G 25 represent 5 and 25 mm glucose, respectively.
| G 5 |
G 25 |
|||||
|---|---|---|---|---|---|---|
| Controls (n = 5) | T2D-αGR (n = 3) | T2D-αNGR (n = 3) | Controls (n = 5) | T2D-αGR (n = 3) | T2D-αNGR (n = 3) | |
| Alanine | ||||||
| M + 2 | 5 ± 1 | 8 ± 4 | 20 ± 8 | 11 ± 1a | 11 ± 4 | 23 ± 9 |
| M + 3 | 1 ± 0.1b | 3 ± 1 | 7 ± 3c | 3 ± 0.3d,e | 2 ± 1 | 8 ± 3 |
| Sum | 6 ± 1 | 11 ± 5 | 27 ± 11 | 14 ± 2a | 14 ± 4 | 31 ± 12 |
| Aspartate | ||||||
| M + 2 | 8 ± 1 | 8 ± 2 | 5 ± 3 | 10 ± 1 | 8 ± 2 | 7 ± 3 |
| M + 3 | 11 ± 2 | 12 ± 4 | 7 ± 4 | 20 ± 2a,e | 18 ± 4 | 9 ± 4 |
| M + 4 | 8 ± 2 | 8 ± 3 | 4 ± 3 | 16 ± 2a,b | 15 ± 3 | 7 ± 3 |
| Sum | 27 ± 5 | 28 ± 8 | 16 ± 9 | 46 ± 5a | 40 ± 9 | 23 ± 11 |
| GABA | ||||||
| M + 2 | 12 ± 2 | 13 ± 5 | 7 ± 3 | 16 ± 1a | 13 ± 3 | 7 ± 4 |
| M + 3 | 8 ± 2 | 9 ± 4 | 5 ± 3 | 14 ± 2a | 10 ± 2 | 6 ± 3 |
| M + 4 | 6 ± 2 | 8 ± 4 | 3 ± 2 | 23 ± 2d,e | 17 ± 4 | 7 ± 4c |
| Sum | 26 ± 5 | 30 ± 13 | 15 ± 8 | 54 ± 4d | 41 ± 9 | 20 ± 10c |
| Glutamate | ||||||
| M + 2 | 13 ± 2 | 13 ± 3 | 10 ± 3 | 15 ± 1 | 14 ± 1 | 13 ± 2 |
| M + 3 | 13 ± 2 | 13 ± 4 | 13 ± 2 | 17 ± 1 | 16 ± 2 | 14 ± 2 |
| M + 4 | 13 ± 3 | 15 ± 5 | 13 ± 2 | 23 ± 2a,e | 23 ± 3 | 15 ± 3 |
| M + 5 | 9 ± 2 | 10 ± 4 | 10 ± 4 | 19 ± 3a | 22 ± 3 | 13 ± 6 |
| Sum | 47 ± 9 | 51 ± 14 | 45 ± 7 | 75 ± 7a | 75 ± 8 | 56 ± 9 |
| Glutamine | ||||||
| M + 2 | 3 ± 1 | 1 ± 0 | 4 ± 2 | 4 ± 2 | 2 ± 1 | 5 ± 1 |
| M + 3 | 2 ± 1 | 4 ± 1 | 2 ± 1 | 5 ± 1 | 7 ± 2 | 3 ± 1 |
| M + 4 | 2 ± 0 | 4 ± 1 | 1 ± 1 | 3 ± 1 | 6 ± 2 | 2 ± 0 |
| M + 5 | 1 ± 0 | 2 ± 1 | 1 ± 0 | 2 ± 0 | 3 ± 1 | 1 ± 0 |
| Sum | 8 ± 1 | 10 ± 3 | 9 ± 4 | 14 ± 3 | 18 ± 5 | 11 ± 1 |
a Versus 5 mm glucose, p < 0.05.
b Versus M + 2, p < 0.05.
c Versus controls, p < 0.05.
d Versus 5 mm glucose, p < 0.01.
e Versus M + 2, p < 0.01.