Oxidative DNA damage is involved in cigarette smoke-induced lung injury in rats.

Abstract

OBJECTIVE:

Reactive oxygen species (ROS) induced by exogenous toxicants are suggested to be involved in carcinogenesis by oxidative modification of DNA. 8-Hydroxyl-2-deoxyguanosine (8-OHdG) has been considered as a reliable biomarker for oxidative DNA damage both in vivo and in vitro studies. But the effect of smoking on oxidative damage has not yet been fully elucidated.

METHODS:

Wistar rats were exposed to cigarette smoke at concentrations of 20 and 60 % for 30 min, twice/day for 45 weeks. Then the histopathology of lung tissues, levels of ROS, 8-OHdG, and total antioxidant (T-AOC), expression of DNA repair enzymes, e.g. 8-oxyguaine DNA glycosylase (OGG1), and MutThomolog 1 (Oxidized Purine Nucleoside Triphosphatase, MTH1) were determined in urine, peripheral blood lymphocytes, and lung tissue.

RESULTS:

The results showed that long-term cigarette smoke exposure can cause obvious damages of lung tissue in rats. In addition, a significant and cigarette smoke concentration-dependent increase in ROS and 8-OHdG were observed compared with the non-exposed control rats. In contrast, the expression of OGG1 and MTH1, and T-AOC levels were obviously decreased after long-term exposure to cigarette smoke.

CONCLUSION:

These findings indicate that long-term exposure to cigarette smoker increases ROS levels, decreases total antioxidant capacity, and interferes DNA repair capacity that eventually induces oxidative DNA damage, which appears to play an important role in cigarette smoke-induced lung injury in rats, and determination of 8-OHdG levels might be a useful method for monitoring oxidative damage in cigarette smokers.

• Authors: Zhihai Chen, Dapeng Wang, Xing Liu, Weiwei Pei, Jianxiang Li, Yi Cao, Jie Zhang, Yan An, Jihua Nie, Jian Tong
• Journal: Environmental health and preventive medicine (Environ Health Prev Med) Vol. 20 Issue 5 Pg. 318-24 (Sep 2015) ISSN: 1347-4715 [Electronic] Japan
• PMID: 25967734 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Antioxidants
• Biomarkers
• Reactive Oxygen Species
• Smoke
• 8-Hydroxy-2'-Deoxyguanosine
• DNA Glycosylases
• OGG1 protein, rat
• DNA Repair Enzymes
• Deoxyguanosine

Topics

• 8-Hydroxy-2'-Deoxyguanosine
• Animals
• Antioxidants (metabolism)
• Biomarkers (blood, metabolism, urine)
• DNA Damage
• DNA Glycosylases (blood, metabolism, urine)
• DNA Repair Enzymes (blood, metabolism, urine)
• Deoxyguanosine (analogs & derivatives, blood, metabolism, urine)
• Dose-Response Relationship, Drug
• Lung Injury (chemically induced)
• Lymphocytes (drug effects)
• Oxidation-Reduction
• Rats
• Rats, Wistar
• Reactive Oxygen Species (blood, metabolism, urine)
• Smoke (adverse effects)
• Tobacco Products (toxicity)