The naturally occurring α-tocopherol stereoisomer RRR-α-tocopherol is predominant in the human infant brain

@article{Kuchan2016TheNO,
  title={The naturally occurring $\alpha$-tocopherol stereoisomer RRR-$\alpha$-tocopherol is predominant in the human infant brain},
  author={Matthew J. Kuchan and S{\o}ren Krogh Jensen and Elizabeth J Johnson and Jacqueline C. Lieblein-Boff},
  journal={British Journal of Nutrition},
  year={2016},
  volume={116},
  pages={126 - 131}
}
Abstract α-Tocopherol is the principal source of vitamin E, an essential nutrient that plays a crucial role in maintaining healthy brain function. Infant formula is routinely supplemented with synthetic α-tocopherol, a racaemic mixture of eight stereoisomers with less bioactivity than the natural stereoisomer RRR-α-tocopherol. α-Tocopherol stereoisomer profiles have not been previously reported in the human brain. In the present study, we analysed total α-tocopherol and α-tocopherol… 

RRR-α-Tocopherol Is the Predominant Stereoisomer of α-Tocopherol in Human Milk

RRR-α-T is the predominant stereoisomer in human milk, concentrations of synthetic 2R stereoisomers were notable, and the relation between milk total α-T and stereoisome profile is complex.

Distribution of α-tocopherol stereoisomers in mink (Mustela vison) organs varies with the amount of all-rac-α-tocopheryl acetate in the diet

The results did reveal the liver’s role as the major organ for accumulation of Σ2S α-tocopherol stereoisomers, and the liver had the highest proportion of ΢2S stereoisomer, and lowest proportion of RRR-α-tocopheryl acetate.

Brain α-Tocopherol Concentration and Stereoisomer Profile Alter Hippocampal Gene Expression in Weanling Mice.

In weanling mouse hippocampi, a network of genes involved in transcription regulation and synapse formation was differentially affected by dam diet αT concentration and source: all rac- αT or RRR-αT.

Supplementation with RRR- or all-rac-α-Tocopherol Differentially Affects the α-Tocopherol Stereoisomer Profile in the Milk and Plasma of Lactating Women.

The α-tocopherol supplementation strategy differentially affected the α-atechopherol milk and plasma stereoisomer profile in lactating women, with RRR-α-tocaperol increased milk and Plasma percentage RRR, whereas all-rac- α-tropopherol acetate reduced these percentages.

Infant Rhesus Macaque Brain α-Tocopherol Stereoisomer Profile Is Differentially Impacted by the Source of α-Tocopherol in Infant Formula

Consumption of infant formulas with natural (NAT-F) αT compared with synthetic (SYN-F), differentially impacted brain αT stereoisomer profiles in infant rhesus macaques, and αT profiles were not explained by α-TTP mRNA or protein expression.

Synthetic α-Tocopherol, Compared with Natural α-Tocopherol, Downregulates Myelin Genes in Cerebella of Adolescent Ttpa-null Mice.

High-dose syntheticα-T compared with natural α-T alters myelin gene expression in the adolescent mouse cerebellum, which could lead to morphological and functional abnormalities later in life.

The Subcellular Distribution of Alpha-Tocopherol in the Adult Primate Brain and Its Relationship with Membrane Arachidonic Acid and Its Oxidation Products

Novel data is reported on α-tocopherol accumulation in primate brain regions and membranes and evidence is provided that α-ocopherol and AA are similarly distributed in PFC and ST membranes, which may reflect a protective effect of α-tropopherol against AA oxidation.

Natural and Synthetic α-Tocopherol Modulate the Neuroinflammatory Response in the Spinal Cord of Adult Ttpa-null Mice

Natural and synthetic α-T supplementation normalized neuroinflammatory markers in neural tissues of 10-mo-old Ttpa−/− mice, which may prevent severe morphological changes during late adulthood.

Effects of dietary RRR &agr;-tocopherol vs all-racemic &agr;-tocopherol on health outcomes

Of the 8 vitamin E analogues, RRR α-tocopherol likely has the greatest effect on health outcomes. Two sources of α-tocopherol, naturally sourced RRR α-tocopherol and synthetic all-racemic

Simultaneous Determination of Alpha-Tocopherol and Alpha-Tocopheryl Acetate in Dairy Products, Plant Milks and Health Supplements by Using SPE and HPLC Method

A solid phase extraction technique for sample cleanup and extraction of α-tocopherol and α-tocopheryl acetate is described and applied to their simultaneous HPLC analysis in dairy products,

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Although specific pathways and specific molecular targets have been sought in a variety of studies, the most likely explanation as to why humans require vitamin E is that it is a fat-soluble antioxidant.

Vitamin E is essential for Purkinje neuron integrity