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Urinary excretion of 2,7,8-trimethyl-2-(β-carboxyethyl)-6-hydroxychroman is a major route of elimination of γ-tocopherol in humans
Open accessAbstract
Little is known of the post-absorptive, metabolic fate of gamma-tocopherol, the major form of vitamin E in North American diets. The objective of this study was to determine the extent of urinary excretion of 2,7, 8-trimethyl-2-(beta-carboxyethyl)-6-hydroxychroman (gamma-CEHC), a recently identified metabolite of gamma-tocopherol. A method for measurement of urinary gamma-CEHC was developed, using gas chromatography-mass spectrometry (GC-MS) with a deuterated internal standard, 2,7,8-trimethyl-2-(beta-carboxyethyl)-(3, 4-2H2)-6-hydroxychroman (d2-gamma-CEHC). This standard was synthesized by dehydrogenation of 6-acetyl-gamma-CEHC followed by deuteration of the resulting 3,4-double bond. The use of d2-gamma-CEHC resulted in accurate determinations of the concentration of d0-gamma-CEHC in human urine. Urine samples containing added d2-gamma-CEHC were treated with beta-glucuronidase, extracted with an organic solvent, and analyzed by GC-MS. Analysis of 24-h urine pools from healthy subjects revealed gamma-CEHC concentrations, normalized against creatinine, ranging from 2.5 to 31.5 micromol/g creatinine, or a total of 4.6 to 29.8 micromol per day. These results correspond to 2-12 mg gamma-tocopherol excreted daily as gamma-CEHC in the urine. Given an estimated mean intake of gamma-tocopherol of 20 mg/day, catabolism of gamma-tocopherol to gamma-CEHC, followed by glucuronide conjugation and urinary excretion, is a major pathway for elimination of gamma-tocopherol in humans.
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Cited by
γ-Tocopherol, the major form of vitamin E in the US diet, deserves more attention
Jiang, Q., Christen, S., Shigenaga, M. K., & Ames, B. N. (2001) · The American Journal of Clinical Nutrition · doi:10.1093/ajcn/74.6.714 · Cited by 776
The European perspective on vitamin E: current knowledge and future research
Brigelius-Flohé, R., Kelly, F. J., Salonen, J. T., Neuzil, J., Zingg, J.-M., & Azzi, A. (2002) · The American Journal of Clinical Nutrition · doi:10.1093/ajcn/76.4.703 · Cited by 585
Vitamin E: Emerging aspects and new directions
Galli, F., Azzi, A., Birringer, M., Cook-Mills, J. M., Eggersdorfer, M., Frank, J., Cruciani, G., Lorkowski, S., & Özer, N. K. (2017) · Free Radical Biology and Medicine · doi:10.1016/j.freeradbiomed.2016.09.017 · Cited by 448
Vitamin E: action, metabolism and perspectives
Herrera, E., & Barbas, C. (2001) · Journal of Physiology and Biochemistry · doi:10.1007/bf03179812 · Cited by 401
Bioavailability and metabolism
Stahl, W. (2002) · Molecular Aspects of Medicine · doi:10.1016/s0098-2997(02)00016-x · Cited by 286
Metadata
- Authors
- Swanson, J. E., Ben, R. N., Burton, G. W., & Parker, R. S.
- Venue
- Journal of Lipid Research
- Publisher
- Elsevier BV
- Published
- 1999-04
- Volume
- 40
- Issue
- 4
- Pages
- 665-671
- ISSN
- 0022-2275 (ISSN-L)
- OpenAlex
- W2119052069
- Cited by
- 197
- References
- 0
- FWCI
- 7.59
- Type
- journal article
- Language
- en
- Open access
- hybrid
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- CoChat. (2026). Citation check: Urinary excretion of 2,7,8-trimethyl-2-(β-carboxyethyl)-6-hydroxychroman is a major route of elimination of γ-tocopherol in humans. https://app.cochat.ai/papers/10.1016/s0022-2275(20)32145-3
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- Swanson, J. E., Ben, R. N., Burton, G. W., & Parker, R. S. (1999). Urinary excretion of 2,7,8-trimethyl-2-(β-carboxyethyl)-6-hydroxychroman is a major route of elimination of γ-tocopherol in humans. Journal of Lipid Research. https://doi.org/10.1016/s0022-2275(20)32145-3
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Contains information from the Semantic Scholar Academic Graph Datasets, made available under the ODC Attribution License (ODC-BY 1.0).
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