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Levels of AdG3, the acrolein-dG adduct, in aortic DNA from acrolein-exposed cockerels on day 1 and day 10 after single 6-hr inhalation exposures to 1 ppm and 10 ppm acrolein. Values are expressed as a percentage of the respective control values at day 1 and day 10.
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Recent reports indicate that many of the cytotoxic and health-threatening components of environmental tobacco smoke (ETS) reside in the vapor phase of the smoke. We have reported previously that inhalation of 1,3-butadiene, a prominent vapor phase component of ETS, accelerates arteriosclerotic plaque development in cockerels. In this study we asked...
Contexts in source publication
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... cockerels in the two exposure groups survived the single 6-hr exposures without any apparent deleterious health effects, according to observation of the animals and gross inspection of internal organs at necropsy. The exposure results (Figure 3) reveal that a single 6-hr inhalation exposure to a steady-state of 1 ppm acrolein in HEPA-filtered air was sufficient to increase acrolein-dG adduct levels in aortic DNA by about 5 times over background levels. Adduct levels in the 10 ppm group were slightly but not significantly increased (p > 0.05) over Figure 2. Typical HPLC chromatograms showing co-migration of the single purified radioactive peak, cor- responding to AdG3, the cyclic acrolein-dG adduct, from aortic DNA of an acrolein-exposed cockerel (B) with AdG3 in the authentic UV standard (A). ...
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... of acrolein-DNA adducts. Ten days after the single 6-hr exposure to either level of acrolein, adduct levels in acrolein-exposed cockerels were reduced to levels comparable to those in control cock- erels (Figure 3). There were no differences (p > 0.05) in adduct levels between the three groups. ...
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... the results suggest a dose response for adduct formation resulting from inhaled acrolein, and, if anything, they overestimate the acrolein levels neces- sary to elicit damage to vascular wall DNA. Because the mean adduct levels are both elevated and so similar in the 1 ppm and 10 ppm groups (Figure 3), the results strongly suggest that high adduct levels would be registered at acrolein levels even below 1 ppm. Although a single 6-hr exposure to 10 ppm acrolein produced no obvious adverse health effects on the cockerels, 6-hr expo- sures to 5 and 10 ppm acrolein for 3 con- secutive days caused significant morbidity and mortality, respectively (data not pre- sented). ...
Citations
... Therefore, a role for acrolein in smoking-related respiratory tract diseases seems to be probable (US Food and Drug Administration Tobacco Product Constituents Subcommittee of the Tobacco Products Scientific Advisory Committee, 2010). A role for smoking-related cardiovascular disease is considered equivocal, as laboratory animal experiments (Conklin et al., 2009;Sithu et al., 2010;Srivastava et al., 2011;Wheat et al., 2011;Hazari et al., 2009;Penn et al., 2001) have shown such activity although the systemic availability of inhaled acrolein is questionable. In the complex matrix of cigarette smoke, acrolein has been discussed to worsen the toxicity of other constituents by depleting GSH-dependent defense pathways (Muller and Gebel, 1998), but this has actually rarely been shown. ...
Tobacco smoke is a complex mixture with over 8700 identified constituents. Smoking causes many diseases including lung cancer, cardiovascular disease, and chronic obstructive pulmonary disease. However, the mechanisms of how cigarette smoke impacts disease initiation or progression are not well understood and individual smoke constituents causing these effects are not generally agreed upon. The studies reported here were part of a series of investigations into the contributions of selected smoke constituents to the biological activity of cigarette smoke. In vitro cytotoxicity measured by the neutral red uptake (NRU) assay and in vitro mutagenicity determined in the Ames bacterial mutagenicity assay (BMA) were selected because these assays are known to produce reproducible, quantitative results for cigarette smoke under standardized exposure conditions. In order to determine the contribution of individual cigarette smoke constituents, a fingerprinting method was developed to semi-quantify the mainstream smoke yields. For cytotoxicity, 90% of gas vapor phase (GVP) cytotoxicity of the Kentucky Reference cigarette 1R4F was explained by 3 aldehydes and 40% of the 1R4F particulate phase cytotoxicity by 10 smoke constituents, e.g., hydroquinone. In the microsuspension version of the BMA, 4 aldehydes accounted for approximately 70% of the GVP mutagenicity. Finally, the benefits of performing such studies along with the difficulties in interpretation in the context of smoking are discussed.
... After inhalation exposure to acrolein (1 and 10 ppm over 6 h) higher acrolein-guanine adduct levels were detected in the abdominal aorta of cockerels. Ten days after the single acrolein exposure, the DNA adduct levels had been repaired and returned to normal values [53]. Data on DNA adduct levels after an oral acrolein exposure in animal tests are not available. ...
... Concerning inhalation intake it was shown by animal experiment that premutagenic DNA adducts develop in the aorta at levels that were five times higher than for the controls. After 10 days the adduct levels returned to normal by DNA repair [53]. The detection of in vivo adducts means, however, that a certain systemic distribution should be expected, at least after inhalation intake. ...
Acrolein is an α,β-unsaturated aldehyde formed by thermal treatment of animal and vegetable fats, carbohydrates and amino acids. In addition it is generated endogenously. As an electrophile, acrolein forms adducts with gluthathione and other cellular components and is therefore cytotoxic. Mutagenicity was shown in some in vitro tests. Acrolein forms different DNA adducts in vivo, but mutagenic and cancerogenous effects have not been demonstrated for oral exposure. In subchronic oral studies, local lesions were detected in the stomach of rats. Systemic effects have not been reported from basic studies. A WHO working group established a tolerable oral acrolein intake of 7.5 μg/kg body weight/day. Acrolein exposure via food cannot be assessed due to analytical difficulties and the lack of reliable content measurements. Human biomonitoring of an acrolein urinary metabolite allows rough estimates of acrolein exposure in the range of a few μg/kg body weight/day. High exposure could be ten times higher after the consumption of certain foods. Although the estimation of the dietary acrolein exposure is associated with uncertainties, it is concluded that a health risk seems to be unlikely.
... While evidence obtained supports lipid peroxidation as an endogenous source for the formation of Acr-dG adducts and other cyclic adducts, the levels of these adducts in tissues can increase upon heavy environmental exposure such as cigarette smoking [16]. Following exposure to high concentrations of Acr in filtered air, a significant increase in Acr-dG adduct formation in the aorta DNA of cockerels was reported [17]. Using the HPLC-based 32 P-postlabeling method, γ-OH-Acr-dG was detected as the major isomer in vivo, and the level of α-OH-Acr-dG was often too low to be detected or quantified [14,15]. ...
Acrolein (Acr), a hazardous air pollutant, reacts readily with deoxyguanosine (dG) in DNA to produce cyclic 1, N2-propanodeoxyguanosine adducts (Acr-dG). Studies demonstrate that these adducts are detected in vivo and may play a role in mutagenesis and carcinogenesis. In the study described here, a quantitative 32P-postlabeling/solid-phase extraction/HPLC method was developed by optimizing the solid-phase extraction and the 32P-postlabeling conditions for analysis of Acr-dG in DNA samples with a detection limit of 0.1 fmol. It was found that Acr-dG can form as an artifact during the assay. Evidence obtained from mass spectrometry indicates that the Acr in water used in the assay is a likely source of artifact formation of Acr-dG. The formation of Acr-dG as an artifact can be effectively blocked by adding glutathione (GSH) to the DNA sample to be analyzed. In addition, Acr-dG was detected as a contaminant in the commercial dG and dT 3'-monophosphate samples. Finally, this method was used to detect Acr-dG in calf thymus and human colon HT29 cell DNA with an excellent linear quantitative relationship.
... Other studies using single components of cigarette smoke have shown that the volatile components, such as acrolein, acetaldehyde, and 1,3-butadiene, are cytotoxic to cells of the vessel wall (Ambalavanan et al., 2001;Penn et al., 2001). Chronic exposure to cigarette smoke has been shown to result in the acceleration of plaque development in humans (Howard et al., 1998b) and experimental animals (Penn and Snyder, 1993;Penn et al., 1994), even in the absence of high fat and/or high cholesterol intake. ...
... After exposure to high concentrations of Acr though inhalation, Acr-dGuo levels in aortic DNA of cockerels increased by 5 fold, however, 10 days after inhalation, adduct levels decreased to those in the control group (174). Another 32 P-postlabeling method was developed by Eder et al., and Cro-dGuo adducts were only found in F344 rats after single gavages of high doses of Cro or repeated gavages of low does, but not in untreated animals (175,176). ...
A large variety of oxidized or newly formed compounds found in both frying fats and fried foods have been evaluated for their toxicological properties. This chapter discusses the details of some of these products. The first products of triacylglycerols (TAGs) are hydroperoxides, epoxides, and hydroperoxides. Acrylamide is metabolized very rapidly after ingestion and moves into the blood and urine, from where it is excreted. After metabolic activation with S‐9 mix, heterocyclic aromatic amines (HAAs) can be assigned to the group of the most strongly mutagenic compounds. The carcinogenic effects of HAAs could be demonstrated in animal trials with rats and mice. A normal antioxidant prevents oxidation of frying medium or frying foods. A pro‐oxidant enhances the oxidation during frying. Thus, pro‐oxidants are not suitable for use during frying. There is no proper guideline for the disposal of fried foods, so procedures for general solid foods are followed.
A stable method, using isotope dilution liquid chromatography-tandem mass spectrometry (LC–MS/MS), to simultaneously determine six aldehyde-DNA adducts was developed and applied to the analysis of human salivary DNA samples. The detection limit of these six DNA adducts was in the range of 0.006–0.014 ng/mL and that of the quantification limit was 0.017–0.026 ng/mL. The intra-day and inter-day precision of all aldehyde-DNA adducts was <10%. The analysis was completed within 25 min. Additionally, a noninvasive technique was used to collect the DNA samples from human saliva. The new method was successfully applied for the analysis of salivary DNA of nonsmokers and smokers. Five aldehyde-DNA adducts were detected in both smoker and nonsmoker salivary DNA, while α-Acr-dG was not detected in all the samples. Among these detected DNA adducts, no significant differences were found between smoker and nonsmoker (p > 0.05). This may due to the individual detoxifying differences or environmental and endogenous exposure. Our study provides a rapid and selective method to simultaneously detect six aldehyde-DNA adducts and to assess potential DNA damage induced by aldehydes
Exposure to tobacco smoke, which contains several harmful and potentially harmful constituents such as acrolein increases cardiovascular disease (CVD) risk. Although high acrolein levels induce pervasive cardiovascular injury, the effects of low-level exposure remain unknown and sensitive biomarkers of acrolein toxicity have not been identified. Identification of such biomarkers is essential to assess the toxicity of acrolein present at low levels in the ambient air or in new tobacco products such as e-cigarettes. Hence, we examined the systemic effects of chronic (12 week) acrolein exposure at concentrations similar to those found in tobacco smoke (0.5 or 1 ppm). Acrolein exposure in mice led to a 2- to 3-fold increase in its urinary metabolite 3-hydroxypropyl mercapturic acid (3-HPMA) with an attendant increase in pulmonary levels of the acrolein-metabolizing enzymes, glutathione S-transferase P and aldose reductase, as well as several Nrf2-regulated antioxidant proteins. Markers of pulmonary endoplasmic reticulum stress and inflammation were unchanged. Exposure to acrolein suppressed circulating levels of endothelial progenitor cells (EPCs) and specific leukocyte subsets (e.g. GR-1+ cells, CD19+ B-cells, CD4+ T-cells; CD11b+ monocytes) whilst other subsets (e.g., CD8+ cells, NK1.1+ cells, Ly6C+ monocytes) were unchanged. Chronic acrolein exposure did not affect systemic glucose tolerance, platelet-leukocyte aggregates or microparticles in blood. These findings suggest that circulating levels of EPCs and specific leukocyte populations are sensitive biomarkers of inhaled acrolein injury and that low-level (<0.5 ppm) acrolein exposure (e.g., in secondhand smoke, vehicle exhaust, e-cigarettes) could increase CVD risk by diminishing endothelium repair or by suppressing immune cells or both.
This chapter reviews studies on the link between smoking and cardiovascular disease. The smoking of tobacco is a major independent risk factor for life-threatening diseases in all four principal arterial territories. The totality of the evidence indicates that this relationship goes beyond statistical association to one of cause-and-effect. Most importantly, compared with other factors such as hypertension, hypercholesterolaemia, and lack of physical activity, cessation of smoking requires a once-only change on the part of the individual, and a change to non-smoking is followed by a rapid and complete disappearance of the excess risk of ischaemic heart disease and stroke, the two most common fatal manifestations of arterial disease.
Acrolein, a mutagenic aldehyde, is produced endogenously by lipid peroxidation and exogenously by combustion of organic materials, including tobacco products. Acrolein reacts with DNA bases forming exocyclic DNA adducts, such as γ-hydroxy-1,N2-propano-2'-deoxyguanosine (γ-HOPdG) and γ-hydroxy-1,N6-propano-2'-deoxyadenosine (γ-HOPdA). The bulky γ-HOPdG adduct blocks DNA synthesis by replicative polymerases but can be bypassed by translesion synthesis polymerases in the nucleus. Although acrolein-induced adducts are likely to be formed and persist in mitochondrial DNA, animal cell mitochondria lack specialized TLS polymerases to tolerate these lesions. Thus, it is important to understand how pol γ, the sole mitochondrial DNA polymerase in human cells, acts on acrolein-adducted DNA. To address this question, we investigated the ability of pol γ to bypass the minor-groove γ-HOPdG and major-groove γ-HOPdA adducts using single nucleotide incorporation and primer extension analyses. The efficiency of pol γ-catalyzed bypass of γ-HOPdG was low and surprisingly, pol γ preferred to incorporate purine nucleotides opposite the adduct. Pol γ also exhibited ~2-fold lower rates of excision of the misincorporated purine nucleotides opposite γ-HOPdG compared to the corresponding nucleotides opposite dG. Extension of primers from the termini opposite γ-HOPdG was accomplished only following error-prone purine nucleotide incorporation. However, pol γ preferentially incorporated dT opposite the γ-HOPdA adduct and efficiently extended primers from the correctly paired terminus, indicating that γ-HOPdA is probably non-mutagenic. In summary, our data suggest that acrolein-induced exocyclic DNA lesions can be bypassed by mitochondrial DNA polymerase but in the case of the minor-groove γ-HOPdG adduct, at the cost of unprecedentedly high mutation rates.
