Distribution and Biodiscrimination of α-Tocopherol Stereoisomers

Abstract

We investigated the distribution and bio-discrimination of α-tocopherol stereoisomers in rats using a newly revised HPLC method. According to the results, we suggest that α-tocopherol stereoisomers are absorbed from the small intestine without discriminating. After uptake into intestinal cells, a-tocopherol stereoisomers are secreted into chylomicrons. Chylomicrons are catabolized in the circulation by the lipoprotein lipase, which forms the chylomicron remnants. After uptake of chylomicron remnants by the liver, α-tocopherol stereoisomers are discriminated in the liver, and RRR-α-tocopherol (rather than SRR-α-tocopherol) is preferentially transported to each tissue. The SRR-α-tocopherol remaining in the liver is metabolized in time and secreted into the bile acids.