Search results for "Vitamin E"

Supercritical Fluid Extraction and Supercritical Fluid Chromatography of Vitamin E in Pharmaceutical Preparations

1999

Application of ACC method to synchronous luminiscence: determination of alpha-tocopherol and alpha-tocopheryl acetate in beverages.

2001

A new method based on the Q parameter, that permits the determination of the C(compound A)/C(compound B) ratio without preparing calibration graphs of the two compounds, is proposed. This method has been applied to signals obtained by synchronous luminiscence. Simultaneous determination of alpha-tocopherol and alpha-tocopheryl acetate in beverages using synchronous fluorescence has been carried out. To isolate the compounds from samples, liquid extraction with n-hexane as the organic phase was employed. The presence of interferences was tested using the apparent content curves (ACC) method and the C(alpha-tocopherol)/C(alpha-tocopheryl acetate) ratio was calculated using the Q parameter. Th…

Vegetable and Fruit Intakes Are Associated with hs-CRP Levels in Pre-Pubertal Girls

2017

The influence of diet on inflammation in children remains unclear. We aimed to analyze the influence of diet on high-sensitivity C-reactive protein (hs-CRP) levels in a pre-pubertal population free of other influences that may affect hs-CRP levels. We determined hs-CRP levels in 571 six- to eight-year-old children using an hs-CRP ELISA kit. Information on food and nutrient intake was obtained through a food-frequency questionnaire. Overall dietary quality was assessed using the Healthy Eating Index (HEI). We found that girls in the highest tertile of hs-CRP levels had a higher intake of saturated fatty acid, and lower intakes of fiber and vitamin E and a lower HEI score when compared to tho…

The Effectiveness of Vitamin E Treatment in Alzheimer’s Disease

2019

Vitamin E was proposed as treatment for Alzheimer’s disease many years ago. However, the effectiveness of the drug is not clear. Vitamin E is an antioxidant and neuroprotector and it has anti-inflammatory and hypocholesterolemic properties, driving to its importance for brain health. Moreover, the levels of vitamin E in Alzheimer’s disease patients are lower than in non-demented controls. Thus, vitamin E could be a good candidate to have beneficial effects against Alzheimer’s. However, evidence is consistent with a limited effectiveness of vitamin E in slowing progression of dementia; the information is mixed and inconclusive. The question is why does vitamin E fail to tre…

‘Threshold effect’ of increasing tocopherol ingestion upon the microsomal epoxide hydrolase activity of rat liver

1990

Impact of high-pressure processing on vitamin E (α-, γ-, and δ-tocopherol), vitamin D (cholecalciferol and ergocalciferol), and fatty acid profiles i…

2012

In the present study, four high-pressure (HP) treatments (100, 200, 300, and 400 MPa) of 9 min duration were evaluated to assess their effect on the lipid fraction (fat-soluble vitamins and fatty acid profile) of an orange juice-milk and a vegetable beverage. After HP treatment, nonsignificant changes in vitamin D(2) and D(3) contents were observed for both beverages. An increase in vitamin E activity was observed in HP beverages when pressures >100 MPa were applied, mainly due to an increase in α-tocopherol content. Only a small reduction in fat content was found for the orange juice-milk beverage, but no changes were observed for the vegetable beverage. A significant decrease in SFA level…

Bioavailability and metabolism.

2002

Aβ and tau toxicities in Alzheimer’s are linked via oxidative stress-induced p38 activation: Protective role of vitamin E

2014

AbstractOxidative stress is a hallmark of Alzheimer’s disease (AD). We propose that rather than causing damage because of the action of free radicals, oxidative stress deranges signaling pathways leading to tau hyperphosphorylation, a hallmark of the disease. Indeed, incubation of neurons in culture with 5 µM beta-amyloid peptide (Aβ) causes an activation of p38 MAPK (p38) that leads to tau hyperphosphorylation. Inhibition of p38 prevents Aβ-induced tau phosphorylation. Aβ-induced effects are prevented when neurons are co-incubated with trolox (the water-soluble analog of vitamin E).We have confirmed these results in vivo, in APP/PS1 double transgenic mice of AD. We have found that APP/PS1 …

Oxidation resistance of LDL is correlated with vitamin E status in beta-thalassemia intermedia.

1998

The alteration of the oxidant/antioxidant balance may affect the susceptibility of low density lipoproteins (LDL) to oxidation in haemolytic disorders such as thalassemia. Thirty patients affected by beta-thalassemia intermedia were examined, and compared with age-matched healthy controls. The mean amount of vitamin E in the thalassemic LDL was lower than control (p0.0001), either when it was calculated on the base of LDL protein (61% decrease) or cholesterol (25% decrease). The LDL resistance to Cu2+-induced oxidation, evaluated as the length of the lag phase before the onset of conjugated diene (CD) lipid hydroperoxide production, was 20% lower than control. Other parameters of LDL suscep…

Biopolyester-based systems containing naturally occurring compounds with enhanced thermooxidative stability

2016

Background This work presents a sustainable approach for the stabilization of polylactic acid (PLA) against thermo-oxidative aging. Methods Naturally occurring phenolic and polyphenolic compounds, such as ferulic acid (FerAc), vanillic acid (VanAc), quercetin (Querc) and vitamin E (VitE), were introduced into PLA. Results The preliminary characterization of the systems formulated containing different amounts of natural stabilizers showed that all compounds used acted as plasticizers, leading to a decrease in rheological functions with respect to neat PLA, without significantly modifying the crystallinity of the raw material. The study of the thermo-oxidative behavior of neat PLA and PLA/nat…