Search results for "vitamin e"

Oxidative stress after moderate to extensive burning in humans.

2000

Lipid peroxidation products, lipid antioxidants, and hematologic and blood chemistry changes were evaluated in plasma of patients after acute burning injury involving 10% (n=8), 20% (n=8), and 40% (n=5) of total body surface area (TBSA), 24 h after burning (baseline) up to 30 days after. Markedly increased plasma levels of malondialdehyde (MDA) were observed at baseline in all patients, according to the extent of the injury, then the values declined progressively. However, levels of MDA remained above normal up to 30 days even in less injured patients. On the other hand, the plasma level of conjugated diene lipid hydroperoxides was only slightly higher than control at the baseline, then dro…

Molecular bases of the treatment of Alzheimer's disease with antioxidants: prevention of oxidative stress

2004

Alzheimer's disease is associated with a systemic oxidative stress situation which can be followed in vivo by determining biomarkers such as plasma lipoperoxides and TBARS levels and the oxidation degree of glutathione in red blood cells. It has been observed that Alzheimer's patients show an increased level of plasma TBARS, which indicates a higher free radical oxidation of plasma unsaturated phospholipids, and an increased oxidation of red blood cells glutathione, which indicates oxidative stress in peripheral cells. This latter, glutathione oxidation, was found to correlate statistically with the cognitive status of the patients. Treatment with vitamin E resulted in an improved cognitive…

Assessment of Vitamin E Intake in Relation to Tolerable Upper Intake Levels

2018

Antioxidant Pathways in Alzheimers Disease: Possibilities of Intervention

2011

Alzheimer's disease (AD) is closely related to the occurrence of oxidative stress. It was claimed that all pathophysiological mechanisms involved in the onset and progression of AD are related to oxidative stress. Thus, it is important to evaluate if there is oxidative stress as well as the mechanism by which this happens in AD patients as well as in animal models of AD. Extracellular plaques of amyloid b peptides (Aβ), a hallmark of the disease, have been postulated to be more protective than damaging in terms of oxidative stress because they may be chemical sinks in which heavy metals are placed. More than a decade ago we reasoned that damage due to Ab might be caused not by extracellular…

Is the chromanol head group of vitamin E nature's final truth on chain-breaking antioxidants?

2012

AbstractTocopherol is believed to be the most potent naturally occurring chain-breaking antioxidant. Hence, its refined phenolic head group chromanol may represent an optimum evolutionary solution to the problem of free-radical chain reactions in the lipid bilayer. To test the universal validity of this assumption beyond phenolic head groups, we have synthesized aromatic amine analogues of vitamin E and trolox with otherwise closely matching physicochemical properties: NH-toc and NH-trox. We have found that NH-toc and NH-trox were significantly more potent free radical scavengers, lipid peroxidation inhibitors and cytoprotective agents than their phenolic templates, tocopherol and trolox. I…

Functional food science and defence against reactive oxidative species

1998

This paper assesses critically the science base that underpins the argument that oxidative damage is a significant causative factor in the development of human diseases and that antioxidants are capable of preventing or ameliorating these disease processes. The assessment has been carried out under a number of headings, and some recommendations for future research are made based on the present day knowledge base. The knowledge database (1) Consideration of the basic science that underlies understanding of the role of free radicals in causing cellular pathologies, and the role of antioxidants in preventing this, shows that an imbalance of reactive oxygen species and antioxidant defence syste…

Biothiols, taurine, and lipid-soluble antioxidants in the edible pulp of Sicilian cactus pear (Opuntia ficus-indica) fruits and changes of bioactive …

2005

Biothiols, taurine, and flavonols, as well as tocopherols and carotenoids have been assessed in the edible pulp of Sicilian red (Sanguigna), yellow (Surfarina), and white (Muscaredda) cultivars of cactus pear. The yellow cultivar has the highest level of reduced glutathione (GSH, 8.1 +/- 0.78 mg/100 g pulp), whereas the white cultivar showed the highest amount of cysteine (1.21 +/- 0.12 mg/100 g pulp). Taurine accounted for 11.7 +/- 1.0 mg/100 g in the yellow pulp, while lower levels were measured in the others. With the exception of kaempferol in the yellow cultivar (2.7 +/- 0.2 microg/100 g pulp), the edible pulp of cactus pear was not a source of flavonols. Very low amounts of lipid-solu…

Antioxidant Activity of Sicilian Pistachio (Pistacia veraL. Var. Bronte) Nut Extract and Its Bioactive Components

2007

Pistacia vera L. is the only species of Pistacia genus producing edible nuts. This paper investigates the antioxidant potential of a Sicilian variety of pistachio nut by chemical as well as biological assays and measured antioxidant vitamins and a number of antioxidant polyphenols in either the hydrophilic and/or the lipophilic nut extract. In accordance with the majority of foods, the total antioxidant activity, measured as a TAA test, was much higher (50-fold) in the hydrophilic than in the lipophilic extract. Substantial amounts of total phenols were measured. The hydrophilic extract inhibited dose-dependently both the metal-dependent and -independent lipid oxidation of bovine liver micr…

Vitamin E supplements in standard rodent diets do not affect antioxidant intervention trials in apo-/-mice: failure of vitamin E to inhibit atherogen…

2001

Low and very low density lipoprotein composition and resistance to copper-induced oxidation are not notably modified in smokers.

1997

To study whether tobacco use was associated with oxidative phenomena affecting lipoproteins, we estimated susceptibility of LDL and VLDL to an in vitro copper-mediated oxidation, and measured serum autoantibody titers against oxidized LDL in 45 middle-age healthy nonsmokers, 35 smokers and 37 ex-smokers of both sexes, taking into account the detailed lipid composition of the lipoproteins. VLDL from female smokers had higher triglyceride, phospholipid, apolipoprotein E and alpha-tocopherol content and showed a higher rate of copper-induced oxidation in comparison with those from nonsmokers (P < or = 0.05) whereas the relative composition of these particles in saturated, mono- or poly-unsatur…