Mechanisms of sulfur mustard analog 2-chloroethyl ethyl sulfide-induced DNA damage in skin epidermal cells and fibroblasts.

Abstract

Employing mouse skin epidermal JB6 cells and dermal fibroblasts, here we examined the mechanisms of DNA damage by 2-chloroethyl ethyl sulfide (CEES), a monofunctional analog of sulfur mustard (SM). CEES exposure caused H2A.X and p53 phosphorylation as well as p53 accumulation in both cell types, starting at 1h, that was sustained for 24h, indicating a DNA-damaging effect of CEES, which was also confirmed and quantified by alkaline comet assay. CEES exposure also induced oxidative stress and oxidative DNA damage in both cell types, measured by an increase in mitochondrial and cellular reactive oxygen species and 8-hydroxydeoxyguanosine levels, respectively. In the studies distinguishing between oxidative and direct DNA damage, 1h pretreatment with glutathione (GSH) or the antioxidant Trolox showed a decrease in CEES-induced oxidative stress and oxidative DNA damage. However, only GSH pretreatment decreased CEES-induced total DNA damage measured by comet assay, H2A.X and p53 phosphorylation, and total p53 levels. This was possibly due to the formation of GSH-CEES conjugates detected by LC-MS analysis. Together, our results show that CEES causes both direct and oxidative DNA damage, suggesting that to rescue SM-caused skin injuries, pleiotropic agents (or cocktails) are needed that could target multiple pathways of mustard skin toxicities.

• Authors: Swetha Inturi, Neera Tewari-Singh, Mallikarjuna Gu, Sangeeta Shrotriya, Joe Gomez, Chapla Agarwal, Carl W White, Rajesh Agarwal
• Journal: Free radical biology & medicine (Free Radic Biol Med) Vol. 51 Issue 12 Pg. 2272-80 (Dec 15 2011) ISSN: 1873-4596 [Electronic] United States
• PMID: 21920433 (Publication Type: Journal Article, Research Support, N.I.H., Extramural)
• Copyright: Copyright © 2011 Elsevier Inc. All rights reserved.

Chemical References

• Chromans
• H2AX protein, mouse
• Histones
• Reactive Oxygen Species
• Tumor Suppressor Protein p53
• 2-chloroethyl ethyl sulfide
• Glutathione
• 6-hydroxy-2,5,7,8-tetramethylchroman-2-carboxylic acid
• Mustard Gas

Topics

• Animals
• Cell Line
• Chromans (pharmacology)
• DNA Damage
• Dose-Response Relationship, Drug
• Fibroblasts (drug effects, metabolism)
• Glutathione (pharmacology)
• Histones (metabolism)
• Mice
• Mice, Hairless
• Mustard Gas (analogs & derivatives, pharmacology)
• Oxidation-Reduction
• Phosphorylation
• Reactive Oxygen Species (metabolism)
• Skin (cytology, drug effects, metabolism)
• Structure-Activity Relationship
• Tumor Suppressor Protein p53 (metabolism)