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| Predicate | Object |
|---|---|
| rdf:type | |
| lifeskim:mentions | |
| pubmed:issue |
1
|
| pubmed:dateCreated |
1995-4-27
|
| pubmed:abstractText |
The Total Radical-Trapping Antioxidant Parameter (TRAP) of 10 freshly prepared human plasmas was measured by a new fluorometric assay. In this method, the rate of peroxidation induced by 2,2'-diazobis (2-amidinopropane) dihydrochloride (ABAP) was monitored through the loss of fluorescence of the protein R-Phycoerythrin (R-PE). The lag-phase induced by plasma was compared to that induced by 6-hydroxy-2,5,7,8-tetramethylchroman-2- carboxylic acid (Trolox, a water-soluble analogue of vitamin E). Proteins (but not their sulphydryl groups) interfere with the analysis, partially protecting R-PE when all plasma antioxidants are exhausted. A Trolox-induced lag-phase must therefore be measured on each plasma sample. We found that ascorbate (2.5-5.3%), alpha-tocopherol (2.9-8.5%), urate (19.6-61.0), and thiol groups (17.3-42.3%) jointly explain up to 70% of TRAP. Thus, either other compounds present in plasma are likely to exert antioxidant action, or a marked synergistic action between antioxidants should be postulated to exist. This latter hypothesis is supported by the finding that the simultaneous inactivation of ascorbate and thiol groups produces a loss in antioxidant capacity of plasma greater (26%) than the sum of the decreases produced by the separate inactivation of each of the two compounds. The proposed method appears simple, reliable, and allows the rapid handling of a reasonable number of freshly prepared plasma samples. Given the rapid loss of TRAP upon storage, the latter characteristic is crucial in studies on humans, involving a large number of subjects.
|
| pubmed:language |
eng
|
| pubmed:journal | |
| pubmed:citationSubset |
IM
|
| pubmed:chemical |
http://linkedlifedata.com/resource/pubmed/chemical/2,2'-azobis(2-amidinopropane),
http://linkedlifedata.com/resource/pubmed/chemical/6-hydroxy-2,5,7,8-tetramethylchroman...,
http://linkedlifedata.com/resource/pubmed/chemical/Amidines,
http://linkedlifedata.com/resource/pubmed/chemical/Antioxidants,
http://linkedlifedata.com/resource/pubmed/chemical/Ascorbic Acid,
http://linkedlifedata.com/resource/pubmed/chemical/Chromans,
http://linkedlifedata.com/resource/pubmed/chemical/Free Radicals,
http://linkedlifedata.com/resource/pubmed/chemical/Peroxides,
http://linkedlifedata.com/resource/pubmed/chemical/Phycoerythrin,
http://linkedlifedata.com/resource/pubmed/chemical/Sulfhydryl Compounds,
http://linkedlifedata.com/resource/pubmed/chemical/Uric Acid,
http://linkedlifedata.com/resource/pubmed/chemical/Vitamin E,
http://linkedlifedata.com/resource/pubmed/chemical/perhydroxyl radical
|
| pubmed:status |
MEDLINE
|
| pubmed:month |
Jan
|
| pubmed:issn |
0891-5849
|
| pubmed:author | |
| pubmed:issnType |
Print
|
| pubmed:volume |
18
|
| pubmed:owner |
NLM
|
| pubmed:authorsComplete |
Y
|
| pubmed:pagination |
29-36
|
| pubmed:dateRevised |
2006-11-15
|
| pubmed:meshHeading |
pubmed-meshheading:7896168-Adult,
pubmed-meshheading:7896168-Amidines,
pubmed-meshheading:7896168-Antioxidants,
pubmed-meshheading:7896168-Ascorbic Acid,
pubmed-meshheading:7896168-Chromans,
pubmed-meshheading:7896168-Free Radicals,
pubmed-meshheading:7896168-Humans,
pubmed-meshheading:7896168-Peroxides,
pubmed-meshheading:7896168-Phycoerythrin,
pubmed-meshheading:7896168-Spectrometry, Fluorescence,
pubmed-meshheading:7896168-Sulfhydryl Compounds,
pubmed-meshheading:7896168-Uric Acid,
pubmed-meshheading:7896168-Vitamin E
|
| pubmed:year |
1995
|
| pubmed:articleTitle |
A fluorescence-based method for measuring total plasma antioxidant capability.
|
| pubmed:affiliation |
National Institute of Nutrition, Rome, Italy.
|
| pubmed:publicationType |
Journal Article,
Research Support, Non-U.S. Gov't
|