Linked Life Data

20708679

Source:http://linkedlifedata.com/resource/pubmed/id/20708679

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
9
pubmed:dateCreated
2010-9-30
pubmed:abstractText
The beneficial health effects of (-)-epigallocatechin-3-gallate (EGCG), the main catechin of green tea, have been attributed to complex interactions with a focus on antioxidative properties. Susceptibility to autoxidation and production of cytotoxic reactive oxygen species (ROS), mostly H(2)O(2), have been suggested to occur in vitro but also in vivo. In this study, we address whether autoxidation-derived H(2)O(2) may be involved in the cytoprotective effects of EGCG. To that end we investigated keratinocyte-derived HaCat and HL-60 promyelocytic leukemia cells with significantly different sensitivities to H(2)O(2) (IC(50) 117.3 versus 58.3 ?M, respectively) and EGCG (134.1 versus 84.1 ?M). HaCat cells significantly resisted cytotoxicity and DNA damage based on enhanced H(2)O(2) clearance, improved DNA repair, and reduced intracellular ROS generation. Cumulative versus bolus EGCG and H(2)O(2) treatment and H(2)O(2) pretreatment before subsequent high-dose EGCG and vice versa significantly reduced DNA damage and cytotoxicity in HaCat cells only. Addition of catalase abolished the protective activities of low-dose H(2)O(2) and EGCG. In summary, our data suggest that autoxidative generation of low-dose H(2)O(2) is a significant player in the cell-type-specific cytoprotection mediated by EGCG and support the hypothesis that regular green tea consumption can contribute as a pro-oxidant to increased resistance against high-dose oxidative stressors.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Nov
pubmed:issn
1873-4596
pubmed:author
pubmed:copyrightInfo
Copyright © 2010 Elsevier Inc. All rights reserved.
pubmed:issnType
Electronic
pubmed:day
15
pubmed:volume
49
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1444-52
pubmed:meshHeading
pubmed:year
2010
pubmed:articleTitle
Hydrogen peroxide mediates EGCG-induced antioxidant protection in human keratinocytes.
pubmed:affiliation
Institute of Cancer Research, Department of Medicine I, Medical University of Vienna, 1090 Vienna, Austria. leonilla.elbling@meduniwien.ac.at
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't