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Updated: Jul 15, 2026
12:15
Quantification of three DNA Lesions by Mass Spectrometry and Assessment of Their Levels in Tissues of Mice Exposed to Ambient Fine Particulate Matter
Published on: May 29, 2019
Hydrogen sulfide induces direct radical-associated DNA damage
Matias S Attene-Ramos1, Elizabeth D Wagner, H Rex Gaskins
1Department of Animal Sciences, Institute for Genomic Biology, University of Illinois at Urbana-Champaign, 364 NSRC, 1101 West Peabody Drive, Urbana, IL 61801, USA.
Molecular Cancer Research : MCR
|May 4, 2007
Summary
Hydrogen sulfide (H2S), produced by gut bacteria, directly damages DNA in mammalian cells. This genotoxicity, mediated by free radicals, may contribute to colorectal cancer development.
Area of Science:
- Gastroenterology
- Molecular Biology
- Toxicology
Background:
- Hydrogen sulfide (H2S) is produced by intestinal sulfate-reducing bacteria.
- H2S and these bacteria are circumstantially linked to ulcerative colitis and colorectal cancer.
- Previous studies indicated sulfide induces genomic DNA damage in mammalian cells.
Purpose of the Study:
- To determine if sulfide is directly genotoxic or requires cellular metabolism.
- To investigate if sulfide genotoxicity involves free radicals and DNA base oxidation.
Main Methods:
- Treatment of naked nuclei from Chinese hamster ovary cells with sulfide.
- Assessment of DNA damage induction by sulfide.
- Evaluation of damage quenching by butylhydroxyanisole.
- Measurement of oxidized DNA bases using formamidopyrimidine [fapy]-DNA glycosylase.
Main Results:
- Sulfide induced DNA damage at concentrations as low as 1 micromol/L.
- Butylhydroxyanisole quenched the sulfide-induced DNA damage.
- Sulfide treatment increased the number of oxidized DNA bases.
Conclusions:
- Sulfide is directly genotoxic to mammalian cells.
- Sulfide-induced genotoxicity is mediated by free radicals and involves DNA base oxidation.
- Sulfide may act as an environmental insult contributing to genomic instability and colorectal cancer.
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