Vitamin E, pharmacology

Treatment Nonpharmacologic treatments of muscle cramping that occurs during hemodialysis include decreasing the ultrafiltration rate and accurately determining the dry weight. Pharmacologic measures include vitamin E, which is administered at doses of 400 IU daily. Other options that are not as well studied include oxazepam and prazosin. 

There are no approved pharmacologic treatments for atrophic AMD. The Age-Related Eye Disease Study showed that a supplement containing ascorbic acid 500 mg, vitamin E 400 IU, beta carotene 15 mg, zinc oxide 80 mg, and cupric oxide 2 mg reduced the rate of clinical progression of all types of AMD by 28% in patients with at least intermediate macular degeneration. No benefit was seen in patients with earlier stages of age-related maculopathy however, the duration of the study may have been insufficient to detect this benefit.25... 

Shvedova, A.A. et al. (2007) Vitamin E deficiency enhances pulmonary inflammatory response and oxidative stress induced by single-walled carbon nanotubes in C57BL/6 mice. Toxicology and Applied Pharmacology, 221 (3), 339-348. 

It should be noted that pharmacological vitamin E is not a free natural RRR-a-tocopherol or synthetic All rac a-tocopherol but its acetate ester. a-Tocopheryl acetate has the phenolic hydroxyl group blocked and therefore, is not a genuine antioxidant, but this compound is very rapidly hydrolyzed in vivo into a-tocopherol. It is interesting that the biological activity of a-tocopheryl acetate is the same as that of a-tocopherol in humans but significantly lower in rats [30]. ( A man is not a rat Professor KU Ingold.)... 

Since glutathione is synthesized in cells in relatively huge amounts, it is seldom applied as pharmacological antioxidant. Furthermore, the mechanism of its antioxidant activity is not so simple as that of vitamins E and C. The major reason is that the GS radical formed during scavenging of free radicals by GSH does not disappear by dimerization but participates in the chain reaction, producing superoxide (Reactions (20)-(23)). Furthermore, it has recently been shown that contrary to previous findings the rate constant for the reaction of GSH with superoxide is relatively small (200-1000 lmol-1 s-1) [211,223],... 

Clinical investigations of the use of vitamin E in treating vascular disorders associated with hypoxia have been more successful [194]. In intermittent claudication, Boyd, Ratcliffe, Jepson and James [195] reported a 78% improvement over a 6 month trial period, while Haeger [ 196, 197] observed significant increases in walking distance in patients with intermittent claudication receiving 300 mg a-tocopherol acetate per day for 2-5 years. This condition currently represents the most potentially useful clinical area for administration of the vitamin in pharmacological doses. 

The hypothesis that hypoxia receptors exist, and can be stimulated by vitamin E and agents in the body which have a structural similarity to the vitamin but which are not necessarily antioxidants, might be useful as a way of investigating the body s physiological and biochemical response to hypoxia. The mechanism of this response could also offer a pharmacological perspective in which new anti-hypoxia drugs could be generated. 

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