Part 3. Assessment of genotoxicity and oxidative damage in rats after chronic exposure to new-technology diesel exhaust in the ACES bioassay.

柴油 柴油机排气 遗传毒性 微粒 柴油机 废物管理 环境科学 化学 工程类 汽车工程 毒性 有机化学
作者
Lance Hallberg,Jonathan B. Ward,Caterina M. Hernandez,Bill T. Ameredes,Jeffrey K. Wickliffe
出处
期刊:PubMed 卷期号: (184): 87-71 被引量:13
链接
标识
摘要

In 2001, the U.S. Environmental Protection Agency (EPA*) and the California Air Resources Board (CARB) adopted new standards for diesel fuel and emissions from heavy-duty diesel engines. By 2007, diesel engines were required to meet these new standards for particulate matter (PM), with other standards to follow. Through a combination of advanced compression-ignition engine technology, development of exhaust aftertreatment systems, and reformulated fuels, stringent standards were introduced. Before the 2007 standards were put in place by the EPA, human health effects linked to diesel exhaust (DE) exposure had been associated with diesel-fuel solvent and combustion components. In earlier research, diesel engine exhaust components were, in turn, linked to increased mutagenicity in cultures of Salmonella typhimurium and mammalian cells (Tokiwa and Ohnishi 1986). In addition, DE was shown to increase both the incidence of tumors and the induction of 8-hydroxy-deoxyguanosine (8-OHdG) adducts in rodents (Ichinose et al. 1997) and total DNA adducts in rats (Bond et al. 1990). Furthermore, DE is composed of a complex mixture of polycyclic aromatic hydrocarbons (PAHs) and particulates. One such PAH, 3-nitrobenzanthrone (3-NBA), is also found in urban air. 3-NBA has been observed to induce micronucleus formation in the DNA of human hepatoma cells (Lamy et al. 2004). The current study is part of the Advanced Collaborative Emissions Study (ACES), a multidisciplinary program carried out by the Health Effects Institute and the Coordinating Research Council. Its purpose was to determine whether recent improvements in the engineering of heavy-duty diesel engines reduce the toxicity associated with exposure to DE components. To this end, we evaluated potential genotoxicity and induction of oxidative stress in bioassays of serum and tissues from Wistar Han rats chronically exposed--for up to 24 months--to DE from a 2007-compliant diesel engine (new-technology diesel exhaust, or NTDE). Genotoxicity was measured as DNA strand breaks in lung tissue, using an alkaline-modified comet assay. As a correlate of possible DNA damage evaluated in the comet assay, concentrations of the free DNA adduct 8-OHdG were evaluated in serum by a competitive enzyme-linked immunosorbent assay (ELISA). The 8-OHdG fragment found in the serum is a specific biomarker for the repair of oxidative DNA damage. In addition, an assay for thiobarbituric acid reactive substances (TBARS) was used to assess oxidative stress and damage in the form of lipid peroxidation in the hippocampus region of the brains of the DE-exposed animals. These endpoints were evaluated at 1, 3, 12, and 24 months of exposure to DE or to a control atmosphere (filtered air). At the concentrations of DE evaluated, there were no significant effects of exposure in male or female rats after 1, 3, 12, or 24 months in any measure of DNA damage in the comet assay (%DNA in tail, tail length, tail moment, or olive moment). The comparison of exposure groups versus control and the comparison of groups by sex for 1 and 3 months of exposure showed no significant differences in serum 8-OHdG concentrations (P > 0.05). The concentrations of 8-OHdG in all exposure groups at 3 months were higher than those in exposure groups at any other time point (P < 0.05). Looking at the levels of 8-OHdG in serum in the 12-month and 24-month groups, we saw a significant difference from control in the 12-month group at the mid and high levels (P < 0.05), as well as some other scattered changes. Sex differences were noted in the 12-month high-level group (P < 0.05). However, these differences did not follow an exposure-dependent pattern. All other comparisons were not significant (P > 0.05). Hippocampal concentrations of TBARs, measured as malondialdehyde (MDA), showed some small and scattered changes in groups exposed to different levels of DE and at different time points, but we did not consider these to be exposure-related. We concluded that exposure to DE in these rats did not produce any significant increase in oxidative damage to lipids or damage to DNA in the form of strand breaks.

科研通智能强力驱动
Strongly Powered by AbleSci AI
更新
PDF的下载单位、IP信息已删除 (2025-6-4)

科研通是完全免费的文献互助平台,具备全网最快的应助速度,最高的求助完成率。 对每一个文献求助,科研通都将尽心尽力,给求助人一个满意的交代。
实时播报
流星雨完成签到 ,获得积分10
2秒前
222发布了新的文献求助10
4秒前
6秒前
zhang完成签到 ,获得积分10
7秒前
zokor完成签到 ,获得积分0
7秒前
斯文败类应助激情的依凝采纳,获得10
8秒前
思源应助静默向上采纳,获得10
9秒前
英吉利25发布了新的文献求助20
10秒前
11秒前
Skywalk满天星完成签到,获得积分10
11秒前
Tin发布了新的文献求助10
11秒前
12秒前
12秒前
kelly完成签到,获得积分10
13秒前
smile完成签到,获得积分10
15秒前
韭菜盒子发布了新的文献求助10
17秒前
19秒前
刘刘完成签到,获得积分10
19秒前
等待的幼晴完成签到,获得积分10
19秒前
水本无忧87完成签到,获得积分10
19秒前
20秒前
所所应助韭菜盒子采纳,获得10
22秒前
xieyuanxing完成签到,获得积分10
23秒前
25秒前
25秒前
白鹭立雪完成签到,获得积分10
26秒前
书生完成签到,获得积分10
27秒前
刘佳敏完成签到 ,获得积分10
27秒前
mhy完成签到 ,获得积分10
27秒前
28秒前
Chiuchiu完成签到,获得积分10
30秒前
3366ll完成签到 ,获得积分10
30秒前
铎铎铎完成签到 ,获得积分10
30秒前
迷人的天抒应助清修采纳,获得10
31秒前
划水完成签到,获得积分10
31秒前
英吉利25发布了新的文献求助10
32秒前
11完成签到 ,获得积分10
32秒前
静默向上发布了新的文献求助10
34秒前
韭菜盒子完成签到,获得积分20
34秒前
34秒前
高分求助中
A new approach to the extrapolation of accelerated life test data 1000
Cognitive Neuroscience: The Biology of the Mind 1000
Technical Brochure TB 814: LPIT applications in HV gas insulated switchgear 1000
Immigrant Incorporation in East Asian Democracies 600
Nucleophilic substitution in azasydnone-modified dinitroanisoles 500
不知道标题是什么 500
A Preliminary Study on Correlation Between Independent Components of Facial Thermal Images and Subjective Assessment of Chronic Stress 500
热门求助领域 (近24小时)
化学 材料科学 医学 生物 工程类 有机化学 生物化学 物理 内科学 纳米技术 计算机科学 化学工程 复合材料 遗传学 基因 物理化学 催化作用 冶金 细胞生物学 免疫学
热门帖子
关注 科研通微信公众号,转发送积分 3968578
求助须知:如何正确求助?哪些是违规求助? 3513393
关于积分的说明 11167478
捐赠科研通 3248836
什么是DOI,文献DOI怎么找? 1794499
邀请新用户注册赠送积分活动 875131
科研通“疑难数据库(出版商)”最低求助积分说明 804664