Table 3.
The vitamin E concentrations and pharmacokinetic parameters.
| Intervention | ||||
|---|---|---|---|---|
| Plasma | Baseline | Vitamin C | Paired t-Test | |
| α-Tocopherol | Average concentration (µmol/L plasma) | 12.5 ± 5.9 | 12.1 ± 5.5 | NS |
| γ-Tocopherol | 0.52 ± 0.38 | 0.60 ± 0.51 | NS | |
| α-CEHC * | Average concentration (µmol/L plasma) | 0.12 ± 0.09 | 0.19 ±0.08 | NS |
| γ-CEHC | 0.47 ± 0.53 | 0.59 ± 0.80 | NS | |
| d6-α-Tocopherol 1 | Cmax (µmol/L) | 0.27 ± 0.15 | 0.32 ± 0.13 | NS |
| Tmax (h) | 19.5 ± 7.0 | 17.5 ± 7.5 | NS | |
| Disappearance rate (pools per day) |
0.65 ± 0.14 | 0.50 ± 0.10 | p = 0.0263 | |
| AUC | 9.78 ± 5.57 | 12.04 ± 4.38 | NS | |
| d2-γ-Tocopherol | Cmax (µmol/L) | 0.20 ± 0.10 | 0.30 ± 0.22 | NS |
| Tmax (h) | 15.5 ± 6.7 | 11.5 ± 1.2 | NS | |
| Disappearance rate (pools per day) |
1.54 ± 0.50 | 1.42 ± 0.55 | NS | |
| AUC | 4.59 ± 3.14 | 5.66 ± 2.77 | NS | |
| d2-γ-CEHC n = 5 |
Cmax (µmol/L) | 0.20 ± 0.14 | 0.22 ± 0.10 | NS |
| Tmax (h) | 16.2 ±7.2 | 12.0 ± 0 | NS | |
| Disappearance rate (pools per day) |
1.25 ± 0.72 | 1.61 ± 0.79 | NS | |
The data shown is calculated from n = 6 participants. Plasma labeled and unlabeled α- and γ-tocopherols were measured simultaneously in the same sample. Plasma labeled and unlabeled α- and γ-CEHCs were measured simultaneously in a separate analysis from the tocopherols. * Unlabeled γ-CEHC was detectable in all subjects’ samples. No d6-α-CEHC was detected in any plasma sample and several samples had no detectable unlabeled α-CEHC. During the baseline trial, α-CEHC was undetectable at multiple times in subjects 1 (once), 5 (at all times) and 6 (twice); while during the vitamin C trial α-CEHC was undetectable in all plasma samples in subjects 1, 5, and 6. During the baseline trial, subject 1 had no detectable d2-γ-CEHC, so this subject’s data is not included for d2-γ-CEHC averages shown in the table (n = 5). 1 The d2-γ- and d6-α-tocopherol disappearance rates were different (p < 0.001) from each other in each trial, while the Cmax were not different, indicating similar absorption, but faster disposition of d2-γ-tocopherol. The fast disposition was also supported by the d2-γ-CEHC disappearance rates, which were similar to those of d2-γ-tocopherol.