Vitamin E (CAS 59-02-9) is the common name given to a group of eight compounds that include four isomers of tocopherol and four isomers of tocotrienol. The compounds are fat soluble and are relevant in a number of biological processes including the reduction of oxidative stress during fatty acid oxidation, as well as functions in gene processing and cell signalling. The most active of the compounds in human is alpha-tocopherol, which is why it is subsequently the most intensely studied of the compounds.
Known Vitamin E Functions
Vitamin E has mainly been studied as a reducer of oxidative stress due to its reactivity with free radicals, as it binds to them and is subsequently reduced by a hydrogen donor and returns to the original form. As vitamin E is fat-soluble, it is primarily found in cell membranes and acts as the first line of defence against external oxidative stress.
Vitamin E, particularly alpha-tocopherol, has been shown to inhibit protein kinase C and stimulate protein phosphatase 2A, which suggests a role in smooth muscle growth. The compounds also have an effect on gene expression of CTGF, a gene coding for connective tissue growth factor, which is a factor responsible for the repair of wounds and regeneration of damaged tissue.
Vitamin E Deficiency in Humans
As vitamin E is important in the development of connective tissue, vitamin E deficiency has been associated with poor neural conduction, leading to neurological issues such as myopathy and spinocerubellar ataxia. Vitamin E deficiency can also lead to blood issues such as anaemia due to the damage to red blood cells as well as poor immune response
Vitamin E Supplementation and Overdose in Humans
To date, studies that have examined additional supplementation with vitamin E has no significant effect in the well-being and health of humans. Supplementation does not increase longevity, does not decrease the risk of stroke or heart disease and does not impact blood sugar levels. In fact, studies are emerging that suggest that supplementation with vitamin E may contribute to prostate cancer development in men and osteoporosis in women.
An overdose of vitamin E, exceeding 1500 IU per day, has been shown to lead to a decrease in the ability of blood to coagulate, which may aggravate existing problems in patients using warfarin or aspirin. An excess of vitamin E may also lead to a deficiency of vitamin K, the compound responsible for blood clotting.
The possible effects of over and underdosing of Vitamin E, medical practices utilize external analytical labs for Mass Spectrometry-focused testing in order to determine the right treatment protocol. These labs utilize stable isotope labeled Vitamin E in order to complete the analysis. IsoSciences offers unlabeled vitamin E and the isotope labeled vitamin E (d6) form.