1. The kinetics of the depletion of alpha-tocopherol in human low-density lipoprotein (LDL) were measured during macrophage-mediated and cell-free oxidation. The formation of oxidatively modified, high-uptake species of LDL in these systems was not detectable until all of the endogenous alpha-tocopherol had been consumed. 2. Supplementation of the alpha-tocopherol content of LDL by loading in v...

Glomerulosclerosis and tubulointerstitial injury are characteristic features seen in the subtotal (5/6) nephrectomy remnant kidney model in the rat. Oxidative stress from renal mass reduction contributes to the glomerular and tubular injury. Previous studies have clearly demonstrated the prevention or inhibition of such injury by an antioxidant such as alpha-tocopherol. However, few data are av...

OBJECTIVE This study aimed to establish reference ranges of serum concentrations of copper, zinc, retinol, alpha-tocopherol, copper:caeruloplasmin and copper:zinc ratios in a group of healthy Omani men and women. MATERIALS AND METHODS Assay techniques employed were atomic absorption spectrophotometry (copper and zinc), reverse-phase high-pressure liquid chromatography with isocratic elution (...

This study is concerned with differences between breast-fed and bottle-fed infants in plasma and red blood cell (RBC)-levels and pattern of tocopherol analogues. Tocopherol levels were determined by High-Performance Liquid Chromatography (HPLC). The results were as follows: 1. In breast-fed infants the plasma contained larger amounts of the alpha and smaller amounts of the gamma form of tocophe...

Tocopherols are amphipathic antioxidants synthesized exclusively by photosynthetic organisms. Tocopherol levels change significantly during plant growth and development and in response to stress, likely as a consequence of the altered expression of pathway-related genes. Homogentisate phytyltransferase (HPT) is a key enzyme limiting tocopherol biosynthesis in unstressed Arabidopsis leaves (E. C...

Alpha-Tocopherol is a classical lipophilic antioxidant well known as a scavenger of free radicals in a hydrophobic milieu. However, it can develop both anti- and prooxidant activity in isolated low density lipoprotein (LDL). It is unknown how these activities are balanced in vivo in human plasma. We studied oxidation of plasma and LDL isolated from healthy donors or from a patient with familial...

Antioxidants such as vitamin E may act differently on skin cells depending on the age of the skin and the level of oxidative damage induced. The effects of alpha-tocopherol (ATF) on H(2)O(2)-induced DNA damage and telomere shortening of normal human skin fibroblast cells derived from young and old individual donors were determined. Fibroblasts were divided into five groups; untreated control, H...

BACKGROUND In adults, RRR-alpha-tocopheryl acetate (natural vitamin E) has approximately twice the biological activity of all-rac-alpha-tocopherol (synthetic vitamin E). Similar studies have not been done in term infants. OBJECTIVE We evaluated the vitamin E and antioxidant status of term infants fed formulas differing in the amount and form of vitamin E acetate. DESIGN A controlled, blinde...

gamma-Tocopherol, the major form of dietary vitamin E, is absorbed in the intestine and is secreted in chylomicrons, which are then transferred to liver lysosomes. Most gamma-tocopherol is transferred to liver microsomes and is catabolized by cytochrome p450. Due to the hydrophobicity of gamma-tocopherol, a binding and transfer protein is plausible, but none have yet been isolated and character...

objective(s): multiple sclerosis (ms) is a serious neurological autoimmune disease, it commonly affects young adults. vitamin e (vit e) is an important component of human diet with antioxidant activity, which protects the body’s biological systems. in order to assess the effect of vit e treatment on this autoimmune disease, we established experimental autoimmune encephalomyelitis (eae), the ani...