Urinary conjugated α-tocopheronolactone--a biomarker of oxidative stress in children with type 1 diabetes.

Increased oxidative stress has been implicated in both the onset and the progression of diabetes mellitus and its complications. The development of easy to measure biomarkers of oxidative stress would, therefore, help in determining in a prospective manner the impact of glycemic control on oxidative stress and macrovascular disease in patients with diabetes. We report the development and validation of a novel method to directly measure the urinary concentrations of the conjugated metabolites of vitamin E (α-tocopherol) and investigate whether the oxidized metabolite α-tocopheronolactone (α-TL) could be used as a biomarker of oxidative stress in children with type 1 diabetes.

Vitamin E and neurological function.

The clinical, neuropathological and electrophysiological evidence that vitamin E (alpha-tocopherol) is essential for normal neurological function will be reviewed. The possible reasons why neural tissues should be particularly affected by a deficiency of this fat-soluble vitamin and the mechanism(s) involved will be considered.

Supplementation with antioxidants and folinic acid for children with Down's syndrome: randomised controlled trial.

Objectives: To assess whether supplementation with antioxidants, folinic acid, or both improves the psychomotor and language development of children with Down's syndrome.

Design: Randomised controlled trial with two by two factorial design.

Setting: Children living in the Midlands, Greater London, and the south west of England.

Effects on neural function of repleting vitamin E-deficient rats with alpha-tocopherol.

A severe and chronic deficiency of vitamin E (alpha-tocopherol) is associated with a characteristic neurological syndrome with typical "clinical," neuropathological, and electrophysiological abnormalities in both humans and experimental animals. Repletion of vitamin E-deficient human subjects with alpha-tocopherol typically halts the progression of the neural signs and symptoms, and in some cases, can result in objective improvement. Electrophysiological parameters provide an objective measure of neural and visual function and improvement of some of these measures has been reported after repletion with vitamin E in humans.

Dietary lipids and vascular function: UK Food Standards Agency workshop report.

The UK Food Standards Agency convened a group of expert scientists to review current research investigating the effect of dietary lipids on vascular function. The workshop highlighted the need for intervention studies to be sufficiently powered for these measures and that they should be corroborated with other, more validated, risk factors for CVD. Work presented at the workshop suggested a beneficial effect of long-chain n-3 PUFA and a detrimental effect of trans fatty acids.

Synthesis and analysis of conjugates of the major vitamin E metabolite, alpha-CEHC.

Glucuronide and sulphate conjugates of 2,5,7,8-tetramethyl-2-(2'-carboxyethyl)-6-hydroxychroman (alpha-CEHC), the major metabolite of alpha-tocopherol (vitamin E), have been synthesized and used for the first direct analysis of conjugated urinary vitamin E metabolites. The metabolites of vitamin E (alpha-tocopherol) could be useful as markers of the function(s) of vitamin E in vivo. A number of methods have been described for the analysis of urinary vitamin E metabolites but these have relied on either acid or enzymatic deconjugation of the metabolites prior to analysis by high performance liquid chromatography or gas chromatography/mass spectrometry.