Sayer Ji
Founder of GreenMedInfo.com

Subscribe to our informative Newsletter & get Nature's Evidence-Based Pharmacy

Our newsletter serves 500,000 with essential news, research & healthy tips, daily.

Download Now

500+ pages of Natural Medicine Alternatives and Information.

Abstract Title:

Oxidative DNA damage and apoptosis induced by benzene metabolites.

Abstract Source:

Cancer Res. 1996 Nov 15;56(22):5172-8. PMID: 8912853

Abstract Author(s):

Y Hiraku, S Kawanishi

Article Affiliation:

Department of Public Health, Graduate School of Medicine, Kyoto University, Japan.

Abstract:

Benzene is a widely recognized human carcinogen. The mechanism of DNA damage induced by major benzene metabolites 1,4-benzoquinone (1,4-BQ) and hydroquinone (1,4-HQ) was investigated in relation to apoptosis and carcinogenesis. Pulsed-field gel electrophoresis showed that cellular DNA strand breakage was induced by benzene metabolites. Internucleosomal DNA fragmentation and morphological changes of apoptotic cells were observed at higher concentrations of benzene metabolites. Flow cytometry showed an increase of peroxides in cultured cells treated with benzene metabolites. 1,4-BQ induced these changes at a much lower concentration than 1,4-HQ. Damage to DNA fragments obtained from the c-Ha-ras-1 proto-oncogene was investigated by a DNA sequencing technique. 1,4-BQ + NADH and 1,4-HQ induced piperidine-labile sites frequently at thymine residues in the presence of Cu(II). Catalase and bathocuproine inhibited DNA damage, suggesting that H2O2 reacts with Cu(I) to produce active species causing DNA damage. Electron spin resonance studies showed that semiquinone radical was produced by NADH-mediated reduction of 1,4-BQ and autoxidation of 1,4-HQ, suggesting that benzene metabolites produce O2- and H2O2 via the formation of semiquinone radical. These results suggest that these benzene metabolites cause DNA damage through H2O2 generation in cells, preceding internucleosomal DNA fragmentation leading to apoptosis. The fates of the cells to apoptosis or mutation might be dependent on the intensity of DNA damage and the ability to repair DNA.

Study Type : In Vitro Study

Print Options


Sayer Ji
Founder of GreenMedInfo.com

Subscribe to our informative Newsletter & get Nature's Evidence-Based Pharmacy

Our newsletter serves 500,000 with essential news, research & healthy tips, daily.

Download Now

500+ pages of Natural Medicine Alternatives and Information.

This website is for information purposes only. By providing the information contained herein we are not diagnosing, treating, curing, mitigating, or preventing any type of disease or medical condition. Before beginning any type of natural, integrative or conventional treatment regimen, it is advisable to seek the advice of a licensed healthcare professional.

© Copyright 2008-2019 GreenMedInfo.com, Journal Articles copyright of original owners, MeSH copyright NLM.