Vitamin E in Human Health

Principal Investigator: Maret G. Traber, Ph.D.

Our laboratory investigates vitamin E. Why do we need it? How much do we need? What is the best way to consume it? Are there adverse effects from consuming too much? Nearly 100 years after the discovery of vitamin E, we recognize that α-tocopherol is required for human life, functions as a potent fat-soluble antioxidant, and is regulated by the human body. A protein in the liver, the α-tocopherol transfer protein (α-TTP), is critical to maintain adequate vitamin E concentrations in the body. We have discovered that this protein is also necessary in the developing brain, likely to deliver vitamin E as the brain is forming. To do these studies we use the zebrafish because its genes are similar to many of those in humans. Using the zebrafish model, we are now seeking to better define the functional role of α-tocopherol by studying vitamin E deficiency.

At the other extreme, we also study vitamin E excess. We have found that vitamin E metabolism serves to prevent excess accumulation of vitamin E in the body. We are currently investigating how these mechanisms might have adverse effects with respect to vitamin K metabolism. Overall, the assessment of the delivery and function of vitamin E in humans has lagged because previously we lacked the appropriate tools. We are in the process of developing an intravenous preparation of vitamin E labeled with deuterium to be able, for the first time, to measure the absorption, biokinetics, and bioavailability of vitamin E in humans.