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Updated: Aug 19, 2026

Quantitative Analysis of Dietary Vitamin A Metabolites in Murine Ocular and Non-Ocular Tissues Using High-Performance Liquid Chromatography
Published on: December 27, 2024
Characterization of cellular uptake and distribution of vitamin E
Yoshiro Saito1, Yasukazu Yoshida, Keiko Nishio
1Human Stress Signal Research Center, National Institute of Advanced Industrial Science and Technology, 1-8-31 Midorigaoka, Ikeda, Osaka 563-8577 Japan. yoshiro-saito@aist.go.jp
Abstract:
We previously reported that tocotrienols acted as more potent inhibitors against selenium deficiency-induced cell death than the corresponding tocopherol isoforms (J. Biol. Chem. 2003;278:39428-39434). In the present study, we first compared the differences in the cellular uptake between alpha-tocopherol (alpha-Toc) and alpha-tocotrienol (alpha-Toc-3). The initial rate of cellular uptake of alpha-Toc-3 was 70-fold higher than that of alpha-Toc. Subcellular fractionation analysis of alpha-Toc-3 and alpha-Toc-fortified cells showed similar cellular distribution of these antioxidants, which was directly proportional to the lipid distribution. The cells containing similar amounts of alpha-Toc-3 and alpha-Toc showed similar resistance against the oxidative stress caused by peroxides. These results suggest that the apparent higher cytoprotective effect of alpha-Toc-3 than alpha-Toc is primarily ascribed to its higher cellular uptake.
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