Document Detail


GSTT2, a phase II gene induced by apple polyphenols, protects colon epithelial cells against genotoxic damage.
MedLine Citation:
PMID:  19753610     Owner:  NLM     Status:  MEDLINE    
Abstract/OtherAbstract:
The potential protective effect of a polyphenol-rich diet for colon carcinogenesis is of great scientific and medical interest. Apples are a main source of polyphenols, and apple juice has been shown to attenuate chemically induced colon carcinogenesis in animal models. In addition to an antioxidant and antiproliferative activity, apple polyphenols have been shown to elevate expression of the phase II gene glutathione S-transferase T2 (GSTT2) in colon epithelial cells. We hypothesized that apple polyphenols may thereby provide protection against oxidant-induced DNA damage. Using GSTT2 promoter constructs and luciferase reporter assays, we found that polyphenolic apple extracts (AE) can directly enhance GSTT2 promoter activity. Comet assays demonstrated that the genotoxicity of the GSTT2 substrate cumene hydroperoxide (CumOOH) was significantly reduced when HT29 colon epithelial cells were pretreated with AE. Overexpression of GSTT2 in HT29 cells significantly reduced CumOOH induced DNA damage, whereas shRNA mediated knockdown of GSTT2 gene expression resulted in higher damage. Our results causally link GSTT2 levels with protection from genotoxic stress, and provide evidence that the antigenotoxic effects of apple polyphenols in vitro are at least in part due to an induction of GSTT2 expression. Induction of phase II genes may contribute to primary chemoprevention of colon cancer by apple polyphenols.
Authors:
Astrid Petermann; Claudia Miene; Gabriele Schulz-Raffelt; Katja Palige; Jana H?lzer; Michael Glei; Frank-D B?hmer
Publication Detail:
Type:  Journal Article; Research Support, Non-U.S. Gov't    
Journal Detail:
Title:  Molecular nutrition & food research     Volume:  53     ISSN:  1613-4133     ISO Abbreviation:  Mol Nutr Food Res     Publication Date:  2009 Oct 
Date Detail:
Created Date:  2009-10-07     Completed Date:  2010-02-17     Revised Date:  -    
Medline Journal Info:
Nlm Unique ID:  101231818     Medline TA:  Mol Nutr Food Res     Country:  Germany    
Other Details:
Languages:  eng     Pagination:  1245-53     Citation Subset:  IM    
Affiliation:
Center for Molecular Biomedicine, Institute of Molecular Cell Biology, Friedrich-Schiller-University Jena, Germany.
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MeSH Terms
Descriptor/Qualifier:
Anticarcinogenic Agents / pharmacology*
Benzene Derivatives / toxicity
Cell Line
Colon / drug effects,  metabolism
Comet Assay
DNA Damage*
Flavonoids / pharmacology*
Fruit / chemistry
Gene Expression Regulation, Enzymologic
Gene Knockdown Techniques
Genes, Reporter
Glutathione Transferase / biosynthesis,  genetics*,  metabolism
HT29 Cells
Humans
Hydrogen Peroxide / analysis
Intestinal Mucosa / drug effects,  metabolism*
Malus / chemistry*
Oxidants / toxicity
Phenols / pharmacology*
Plant Extracts / pharmacology*
Promoter Regions, Genetic
RNA, Small Interfering
Chemical
Reg. No./Substance:
0/Anticarcinogenic Agents; 0/Benzene Derivatives; 0/Flavonoids; 0/Oxidants; 0/Phenols; 0/Plant Extracts; 0/RNA, Small Interfering; 0/polyphenols; 7722-84-1/Hydrogen Peroxide; 80-15-9/cumene hydroperoxide; EC 2.5.1.-/GSTT2 protein, human; EC 2.5.1.18/Glutathione Transferase

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine


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