For Heart Health, Mixed Tocopherols Superior to Alpha-Tocopherol Alone

UPPSALA, Sweden--Mixed tocopherols may be superior at inhibiting lipid peroxidation, and thereby atherosclerotic cardiovascular disease, than alpha-tocopherol alone, according to an in vitro study printed in the May issue of the Journal of Cardiovascular Pharmacology (39, 5:714-21, 2002) (www.cardiovascularpharm.com). Investigators from the University of Uppsala began with the hypothesis that mixed tocopherols have been linked with preventing cardiovascular disease, although studies utilizing alpha-tocopherol alone have shown little to no effect in clinical trials.

Researchers incubated human erythrocytes (cells in the blood that carry hemoglobin and other gasses through the body) with different concentrations of alpha-tocopherol or mixed tocopherols (consisting of gamma-, delta- and alpha-tocopherols) and then exposed them to hydrogen peroxide, which induced oxidative damage. The hydrogen peroxide also increased lipid peroxidation and decreased polyunsaturated fatty acids in the erythrocytes.

Through high-performance liquid chromatography (HPLC), researchers learned that both alpha-tocopherol and the tocopherol mixture protected the cells from lipid peroxidation, although the mixture was more potent than alpha-tocopherol alone. In addition, it was noted that the erythrocytes in the mixed tocopherol solution exhibited increased tocopherol concentrations, with greater uptake of gamma- and delta-tocopherols than alpha-tocopherol. Researchers concluded that a mixture of tocopherols is more protective against lipid peroxidation in human erythrocytes than alpha-tocopherol alone, due to the higher uptake of gamma- and delta-tocopherols in the cells.

"When we think of vitamin E, we think of alpha-tocopherol," said Dick Beitel, vice president of sales for Kearny, N.J.-based Pharmachem Laboratories Inc. "But alpha-tocopherol is only one of eight isomers of vitamin E. The industry has suddenly started to look at moving from just one of the isomers--alpha-tocopherol--to a mixed tocopherol, which is actually alpha-, beta-, delta- and gamma-tocopherol. However, that is only half of the equation. Really to get the total nature of vitamin E, development should continue to go forth to include all eight isomers: alpha-, beta-, delta- and gamma-tocopherol and the same double bond for alpha-, beta-, delta- and gamma-tocotrienol."