| 1. |
- Hochstenbach, Kevin, et al.
(författare)
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Global gene expression analysis in cord blood reveals gender specific differences in response to carcinogenic exposure in utero
- 2012
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Ingår i: Cancer Epidemiology, Biomarkers and Prevention. - 1055-9965 .- 1538-7755. ; 21:10, s. 1756-1767
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Tidskriftsartikel (refereegranskat)abstract
- Background: It has been suggested that fetal carcinogenic exposure might lead to predisposition to develop cancer during childhood or in later life possibly through modulation of the fetal transcriptome. Because gender effects in the incidence of childhood cancers have been described, we hypothesized differences at the transcriptomic level in cord blood between male and female newborns as a consequence of fetal carcinogenic exposure. The objective was to investigate whether transcriptomic responses to dietary genotoxic and nongenotoxic carcinogens show gender-specific mechanisms-of-action relevant for chemical carcinogenesis. Methods: Global gene expression was applied in umbilical cord blood samples, the CALUX-assay was used for measuring dioxin(-like), androgen(-like), and estrogen(-like) internal exposure, and acrylamide-hemoglobin adduct levels were determined by mass spectrometry adduct-FIRE-procedure (TM). To link gene expression to an established phenotypic biomarker of cancer risk, micronuclei frequencies were investigated. Results: While exposure levels did not differ between sexes at birth, important gender-specific differences were observed in gene expressions associated with these exposures linked with cell cycle, the immune system and more general cellular processes such as posttranslation. Moreover, oppositely correlating leukemia/lymphoma genes between male and female newborns were identified in relation to the different biomarkers of exposure that might be relevant to male-specific predisposition to develop these cancers in childhood. Conclusions/Impact: This study reveals different transcriptomic responses to environmental carcinogens between the sexes. In particular, male-specific TNF-alpha-NF-kB signaling upon dioxin exposure and activation of the Wnt-pathway in boys upon acrylamide exposure might represent possible mechanistic explanations for gender specificity in the incidence of childhood leukemia.
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| 2. |
- Merlo, Domenico Franco, et al.
(författare)
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Micronuclei in Cord Blood Lymphocytes and Associations with Biomarkers of Exposure to Carcinogens and Hormonally Active Factors, Gene Polymorphisms, and Gene Expression : The NewGeneris Cohort
- 2014
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Ingår i: Journal of Environmental Health Perspectives. - : Environmental Health Perspectives. - 0091-6765 .- 1552-9924. ; 122:2, s. 193-200
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Tidskriftsartikel (refereegranskat)abstract
- Background: Leukemia incidence has increased in recent decades among European children, -suggesting that early-life environmental exposures play an important role in disease development. Objectives: We investigated the hypothesis that childhood susceptibility may increase as a result of in utero exposure to carcinogens and hormonally acting factors. Using cord blood samples from the NewGeneris cohort, we examined associations between a range of biomarkers of carcinogen exposure and hormonally acting factors with micronuclei (MN) frequency as a proxy measure of cancer risk. Associations with gene expression and genotype were also explored. Methods: DNA and protein adducts, gene expression profiles, circulating hormonally acting factors, and GWAS (genome-wide association study) data were investigated in relation to genomic damage measured by MN frequency in lymphocytes from 623 newborns enrolled between 2006 and 2010 across Europe. Results: Malondialdehyde DNA adducts (M(1)dG) were associated with increased MN frequency in binucleated lymphocytes (MNBN), and exposure to androgenic, estrogenic, and dioxin-like compounds was associated with MN frequency in mononucleated lymphocytes (MNMONO), although no monotonic exposure-outcome relationship was observed. Lower frequencies of MNBN were associated with a 1-unit increase expression of PDCD11, LATS2, TRIM13, CD28, SMC1A, IL7R, and NIPBL genes. Gene expression was significantly higher in association with the highest versus lowest category of bulky and M(1)dG-DNA adducts for five and six genes, respectively. Gene expression levels were significantly lower for 11 genes in association with the highest versus lowest category of plasma AR CALUX (R) (chemically activated luciferase expression for androgens) (8 genes), ER alpha CALUX (R) (for estrogens) (2 genes), and DR CALUX (R) (for dioxins). Several SNPs (single-nucleotide polymorphisms) on chromosome 11 near FOLH1 significantly modified associations between androgen activity and MNBN frequency. Polymorphisms in EPHX1/ 2 and CYP2E1 were associated with MNBN. Conclusion: We measured in utero exposure to selected environmental carcinogens and circulating hormonally acting factors and detected associations with MN frequency in newborns circulating T lymphocytes. The results highlight mechanisms that may contribute to carcinogen-induced leukemia and require further research.
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| 3. |
- Bradshaw, Clare, et al.
(författare)
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Effects of benthos, temperature and dose on the fate of HBCDD in experimental coastal ecosystems
- 2015
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Ingår i: Environmental Toxicology and Chemistry. - : Wiley. - 0730-7268 .- 1552-8618. ; 34:6, s. 1246-1257
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Tidskriftsartikel (refereegranskat)abstract
- We studied the fate of the brominated flame retardant hexabromocyclododecane (HBCDD) added in a particulate suspension to experimental ecosystems assembled from brackish (Baltic Sea) coastal bays. Two experiments examined how A) benthic macrofauna (over 21 d), and B) increased temperature (14 d), affected HBCDD concentrations and fractionation of α, β and γ diastereomers in the water, sediment and biota. A third experiment (C) run over three seasons (231 d), studied the effect of HBCDD dose on the same endpoints. In all treatments of the three experiments, HBCDD partitioned mainly to the sediment, and this proportion increased with time. Presence of macrofauna tended to increase the HBCDD concentration in the sediment and decreased its concentration in the water. Increased temperature (+5 °C) decreased the amount of HBCDD in sediment and water but not in the filter- and deposit-feeding infaunal bivalves (Macoma balthica). The partitioning between water, sediment and biota was not concentration dependent. In all treatments, sediment became enriched in γ-HBCDD, M. balthica in α-HBCDD and water in α- and β-HBCDD. Bioaccumulation of HBCDD in M. balthica was high in all experiments (logBSAF > 1.25), the α diastereomer contributing the most (logBSAF 2.1 to 5.2). There is a risk of trophic transfer of HBCDD from benthic to pelagic food webs, and secondary poisoning of marine consumers. This article is protected by copyright. All rights reserved.
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| 4. |
- Bradshaw, Clare, et al.
(författare)
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Effects of benthos, temperature, and dose on the fate of hexabromocyclododecane in experimental coastal ecosystems
- 2015
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Ingår i: Environmental Toxicology and Chemistry. - : Wiley. - 0730-7268 .- 1552-8618. ; 34:6, s. 1246-1257
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Tidskriftsartikel (refereegranskat)abstract
- The authors studied the fate of the brominated flame retardant hexabromocyclododecane (HBCDD) added in a particulate suspension to experimental ecosystems assembled from brackish (Baltic Sea) coastal bays. Two experiments examined how benthic macrofauna (over 21 d) and increased temperature (14 d) affected HBCDD concentrations and fractionation of , , and diastereomers in the water, sediment, and biota. A third experiment run over 3 seasons (231 d), studied the effect of HBCDD dose on the same endpoints. In all treatments of the 3 experiments, HBCDD partitioned mainly to the sediment, and this proportion increased with time. Presence of macrofauna tended to increase the HBCDD concentration in the sediment and decreased its concentration in the water. Increased temperature (+5 degrees C) decreased the amount of HBCDD in sediment and water but not in the filter- and deposit-feeding infaunal bivalves (Macoma balthica). The partitioning between water, sediment, and biota was not concentration dependent. In all treatments, sediment became enriched in -HBCDD, M. balthica in -HBCDD, and water in - and -HBCDD. Bioaccumulation of HBCDD in M. balthica was high in all experiments (log biota-sediment accumulation factor [BSAF] > 1.25), the diastereomer contributing the most (log BSAF 2.1-5.2). There is a risk of trophic transfer of HBCDD from benthic to pelagic food webs, as well as secondary poisoning of marine consumers. Environ Toxicol Chem 2015;34:1246-1257.
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| 5. |
- Carlsson, Henrik, et al.
(författare)
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LC–MS/MS Screening Strategy for Unknown Adducts to N-Terminal Valine in Hemoglobin Applied to Smokers and Nonsmokers
- 2014
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Ingår i: Chemical Research in Toxicology. - : American Chemical Society (ACS). - 0893-228X .- 1520-5010. ; 27:12, s. 2062-2070
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Tidskriftsartikel (refereegranskat)abstract
- Electrophilically reactive compounds have the ability to form adducts with nucleophilic sites in DNA and proteins, constituting a risk for toxic effects. Mass spectrometric detection of adducts to N-terminal valine in hemoglobin (Hb) after detachment by modified Edman degradation procedures is one approach for in vivo monitoring of exposure to electrophilic compounds/metabolites. So far, applications have been limited to one or a few selected reactive species, such as acrylamide and its metabolite glycidamide. This article presents a novel screening strategy for unknown Hb adducts to be used as a basis for an adductomic approach. The method is based on a modified Edman procedure, FIRE, specifically developed for LC-MS/MS analysis of N-terminal valine adducts in Hb detached as fluorescein thiohydantoin (FTH) derivatives. The aim is to detect and identify a priori unknown Hb adducts in human blood samples. Screening of valine adducts was performed by stepwise scanning of precursor ions in small mass increments, monitoring four fragments common for the FTH derivative of valine with different N-substitutions in the multiple-reaction mode, covering a mass range of 135 Da (m/z 503-638). Samples from six smokers and six nonsmokers were analyzed. Control experiments were performed to compare these results with known adducts and to check for artifactual formation of adducts. In all samples of smokers and nonsmokers, seven adducts were identified, of which six have previously been studied. Nineteen unknown adducts were observed, and 14 of those exhibited fragmentation patterns similar to earlier studied FTH derivatives of adducts to valine. Identification of the unknown adducts will be the focus of future work. The presented methodology is a promising screening tool using Hb adducts to indicate exposure to potentially toxic electrophilic compounds and metabolites.
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| 6. |
- Duarte-Salles, Talita, et al.
(författare)
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Dietary Acrylamide Intake during Pregnancy and Fetal Growth-Results from the Norwegian Mother and Child Cohort Study (MoBa)
- 2013
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Ingår i: Journal of Environmental Health Perspectives. - : Environmental Health Perspectives. - 0091-6765 .- 1552-9924. ; 121:3, s. 374-379
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Acrylamide has shown developmental and reproductive toxicity in animals, as well as neurotoxic effects in humans with occupational exposures. Because it is widespread in food and can pass through the human placenta, concerns have been raised about potential developmental effects of dietary exposures in humans. OBJECTIVES: We assessed associations of prenatal exposure to dietary acrylamide with small for gestational age (SGA) and birth weight. METHODS: This study included 50,651 women in the Norwegian Mother and Child Cohort Study (MoBa). Acrylamide exposure assessment was based on intake estimates obtained from a food frequency questionnaire (FFQ), which were compared with hemoglobin (Hb) adduct measurements reflecting acrylamide exposure in a subset of samples (n = 79). Data on infant birth weight and gestational age were obtained from the Medical Birth Registry of Norway. Multivariable regression was used to estimate associations between prenatal acrylamide and birth outcomes. RESULTS: Acrylamide intake during pregnancy was negatively associated with fetal growth. When women in the highest quartile of acrylamide intake were compared with women in the lowest quartile, the multivariable-adjusted odds ratio (OR) for SGA was 1.11 (95% CI: 1.02, 1.21) and the coefficient for birth weight was -25.7 g (95% CI: -35.9, -15.4). Results were similar after excluding mothers who smoked during pregnancy. Maternal acrylamide-and glycidamide-Hb adduct levels were correlated with estimated dietary acrylamide intakes (Spearman correlations = 0.24; 95% CI: 0.02, 0.44; and 0.48; 95% CI: 0.29, 0.63, respectively). CONCLUSIONS: Lowering dietary acrylamide intake during pregnancy may improve fetal growth.
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| 7. |
- Gutzkow, K. B., et al.
(författare)
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Enhanced susceptibility of obese mice to glycidamide-induced sperm chromatin damage without increased oxidative stress
- 2016
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Ingår i: Andrology. - : Wiley. - 2047-2919 .- 2047-2927. ; 4:6, s. 1092-1114
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Tidskriftsartikel (refereegranskat)abstract
- Diet-induced obesity is known to impair male reproduction and may aggravate the male reproductive toxicity of the food contaminant acrylamide. Exposure of male mice to acrylamide induces paternally mediated pre- and post-implantation losses because of spermatozoal toxicity and these effects are potentiated in mice fed a high-fat diet. Glycidamide - an acrylamide metabolite - is the primary mediator of reproductive effects in males. The mechanisms causing the interaction between diet and acrylamide are not clear. However, diet-induced obesity is associated with oxidative stress in male reproductive tissues which might contribute to increased germ cell susceptibility. In this study, we investigated whether a moderate diet-induced obesity regimen could interfere with glycidamide-induced spermatozoal toxicity and increase oxidative stress. For this purpose, sperm chromatin integrity, oxidised DNA and protein levels, transcript levels of oxidative stress responsive genes and glycidamide-induced DNA and haemoglobin adducts were analysed in samples from male mice exposed to a high-fat diet for 6 weeks in combination with a single glycidamide exposure 7 days prior to sacrifice. We found that glycidamide-induced sperm DNA fragmentation was markedly higher in obese than in lean mice. However, the levels of oxidised DNA and/or protein in blood, liver and testicular tissue was lower in obese than in lean mice. Accompanying the reduced level of oxidised macromolecules, the transcript levels of several oxidative stress-related genes were altered in the liver and testis from obese mice suggesting induction of an antioxidant response in these animals. The haemoglobin-glycidamide adduct levels were higher in obese than in lean animals, whereas obesity did not seem to increase the level of glycidamide-induced DNA adducts. These findings show that a moderate diet-induced obesity regimen may potentiate glycidamide-induced sperm cells toxicity and suggest that the increase in glycidamide-induced sperm toxicity observed in obese mice does not depend on overt oxidative stress.
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| 8. |
- Milton, Freja, et al.
(författare)
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Zinks spridning i miljön - En litteraturstudie
- 2018
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Zinc is one of our most common and most occurring metals. The metal is very useful and is used to prevent corrosion. Zinc is toxic for water living organisms when it occurs in concentrations over 20 μg/l. The metal affects the aquatic organism’s reproduction, survival and growth negatively. It is especially young individuals and embryos who will be affected by enhanced concentrations of zinc. The toxicity for zinc is determined by its bioavailability and is affected by its metal form, pH, redox ratio, DOC etc.The largest emissions of zinc occur to water followed by emissions to air. Within both categories diffuse emission is most dominated. The biggest zinc emission source is leakages from wooded ground followed by atmospheric deposition on the water surface. Industries is the greatest point source. The leakage from wooded ground is derived from atmospheric deposition of zinc.This report has chosen to focus and examine three types of human activities who causes zinc emissions. The activities which has been chosen for more extensive studies are artificial turfs with rubber granulates, traffic related emissions and emissions from goods. The traffic causes zinc emissions around the roads and the pollutant is usually not spread far from the road. Locally high levels of zinc along the roadside can therefore occur. Galvanized goods are believed to be a major secondary emission source even in places other than the traffic environment.Negative effects on aquatic or soil environment due to enhanced concentrations of zinc in Sweden is considered low. Generally, the chemical status in surface water in watercourses are good. Despite this, the risk of environment impact due to zinc should not be underestimated. Zinc have been accumulated in the soil for a long time. If the soil or sediments characteristics changes it could lead to devastating effects on nearby recipients.
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| 9. |
- O'Callaghan-Gordo, Cristina, et al.
(författare)
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Maternal diet during pregnancy and micronuclei frequency in peripheral blood T lymphocytes in mothers and newborns (Rhea cohort, Crete)
- 2018
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Ingår i: European Journal of Nutrition. - : Springer Science and Business Media LLC. - 1436-6207 .- 1436-6215. ; 57:1, s. 209-218
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Tidskriftsartikel (refereegranskat)abstract
- Purpose The study assessed whether diet and adherence to cancer prevention guidelines during pregnancy were associated with micronucleus (MN) frequency in mothers and newborns. MN is biomarkers of early genetic effects that have been associated with cancer risk in adults. Methods A total of 188 mothers and 200 newborns from the Rhea cohort (Greece) were included in the study. At early-mid pregnancy, we conducted personal interviews and a validated food frequency questionnaire was completed. With this information, we constructed a score reflecting adherence to the World Cancer Research Fund/American Institute for Cancer Research cancer prevention guidelines on diet, physical activity and body fatness. At delivery, maternal and/or cord blood was collected to measure DNA and hemoglobin adducts of dietary origin and frequencies of MN in binucleated and mononucleated T lymphocytes (MNBN and MNMONO). Results In mothers, higher levels of red meat consumption were associated with increased MNBN frequency [2nd tertile IRR = 1.34 (1.00, 1.80), 3rd tertile IRR = 1.33 (0.96, 1.85)] and MNMONO frequency [2nd tertile IRR = 1.53 (0.84, 2.77), 3rd tertile IRR = 2.69 (1.44, 5.05)]. The opposite trend was observed for MNBN in newborns [2nd tertile IRR = 0.64 (0.44, 0.94), 3rd tertile IRR = 0.68 (0.46, 1.01)], and no association was observed with MNMONO. Increased MN frequency in pregnant women with high red meat consumption is consistent with previous knowledge. Conclusions Our results also suggest exposure to genotoxics during pregnancy might affect differently mothers and newborns. The predictive value of MN as biomarker for childhood cancer, rather than adulthood, remains unclear. With few exceptions, the association between maternal carcinogenic exposures during pregnancy and childhood cancer or early biologic effect biomarkers remains poorly understood.
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| 10. |
- Pedersen, Marie, et al.
(författare)
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Birth Weight, Head Circumference, and Prenatal Exposure to Acrylamide from Maternal Diet : The European Prospective Mother-Child Study (NewGeneris)
- 2012
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Ingår i: Journal of Environmental Health Perspectives. - : Environmental Health Perspectives. - 0091-6765 .- 1552-9924. ; 120:12, s. 1739-1745
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Acrylamide is a common dietary exposure that crosses the human placenta. It is classified as a probable human carcinogen, and developmental toxicity has been observed in rodents. OBJECTIVES: We examined the associations between prenatal exposure to acrylamide and birth outcomes in a prospective European mother child study. METHODS: Hemoglobin (Hb) adducts of acrylamide and its metabolite glycidamide were measured in cord blood (reflecting cumulated exposure in the last months of pregnancy) from 1,101 singleton pregnant women recruited in Denmark, England, Greece, Norway, and Spain during 2006-2010. Maternal diet was estimated through food-frequency questionnaires. RESULTS: Both acrylamide and glycidamide Hb adducts were associated with a statistically significant reduction in birth weight and head circumference. The estimated difference in birth weight for infants in the highest versus lowest quartile of acrylamide Hb adduct levels after adjusting for gestational age and country was -132 g (95% CI: -207, -56); the corresponding difference for head circumference was -0.33 cm (95% CI: -0.61, -0.06). Findings were similar in infants of nonsmokers, were consistent across countries, and remained after adjustment for Factors associated with reduced birth weight. Maternal consumption of foods rich in acrylamide, such as fried potatoes, was associated with cord blood acrylamide adduct levels and with reduced birth weight. CONCLUSIONS: Dietary exposure to acrylamide was associated with reduced birth weight and head circumference. Consumption of specific foods during pregnancy was associated with higher acrylamide exposure in utero. IF confirmed, these findings suggest that dietary intake of acrylamide should be reduced among pregnant women.
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| 11. |
- Pedersen, Marie, et al.
(författare)
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Bulky DNA Adducts in Cord Blood, Maternal Fruit-and-Vegetable Consumption, and Birth Weight in a European Mother-Child Study (NewGeneris)
- 2013
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Ingår i: Journal of Environmental Health Perspectives. - : Environmental Health Perspectives. - 0091-6765 .- 1552-9924. ; 121:10, s. 1200-1206
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Tidskriftsartikel (refereegranskat)abstract
- Background: Tobacco-smoke, airborne, and dietary exposures to polycyclic aromatic-hydrocarbons (PAHs) have been associated with reduced prenatal growth. Evidence from -biomarker-based studies of low-exposed populations is limited. Bulky DNA adducts in cord blood reflect the prenatal effective dose to several genotoxic agents including PAHs. Objectives: We estimated the association between bulky DNA adduct levels and birth weight in a multicenter study and examined modification of this association by maternal intake of fruits and vegetables during pregnancy. Methods: Pregnant women from Denmark, England, Greece, Norway, and Spain were recruited in 2006-2010. Adduct levels were measured by the 32P-postlabeling technique in white blood cells from 229 mothers and 612 newborns. Maternal diet was examined through questionnaires. Results: Adduct levels in maternal and cord blood samples were similar and positively correlated (median, 12.1 vs. 11.4 adducts in 108 nucleotides; Spearman rank correlation coefficient = 0.66, p < 0.001). Cord blood adduct levels were negatively associated with birth weight, with an estimated difference in mean birth weight of -129 g (95% CI: -233, -25 g) for infants in the highest versus lowest tertile of adducts. The negative association with birth weight was limited to births in Norway, Denmark, and England, the countries with the lowest adduct levels, and was more pronounced in births to mothers with low intake of fruits and vegetables (-248 g; 95% CI: -405, -92 g) compared with those with high intake (-58 g; 95% CI: -206, 90 g). Conclusions: Maternal exposure to genotoxic agents that induce the formation of bulky DNA adducts may affect intrauterine growth. Maternal fruit and vegetable consumption may be protective.
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| 12. |
- Rydberg, Per, et al.
(författare)
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LC/MS/MS analysis of N-terminal protein adducts with improved sensitivity : A comparison of selected Edman isothiocyanate reagents.
- 2009
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Ingår i: International Journal of Analytical Chemistry. - : Hindawi Limited. - 1687-8779 .- 1687-8760.
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Tidskriftsartikel (refereegranskat)abstract
- This study provides a basis for a new and straightforward method for LC/MS/MS-based screening of N-terminal protein adducts. This procedure is denoted the “FIRE procedure” as fluorescein isothiocyanate (FITC) gave superior sensitivity by LC/MS/MS when measuring adducts (R) of electrophilic compounds with a modified Edman procedure. The principles of the FIRE-procedure are that adducts to N-terminal amino acids selectively are detached and measured from of proteins after derivatisation by isothiocyanate Edman reagents. In this study, FITC, 4-N,N-dimethylaminoazobenzene 4′-isothiocyanate (DABITC) and 4-dimethylamino-1-naphthyl isothiocyanate (DNITC) were used to synthesize thiohydantoin analytes from valine and N-methylvaline. The sensitivity by LC/MS/MS was enhanced by up to three orders of magnitude as compared to phenyl isothiocyanate and higher as compared to pentafluorophenyl isothiocyanate. The FITC reagent will enable measurements of low background adduct levels. Synthesized analytes were characterised with, for example, 1H NMR, 13C NMR, LC/MS/MS, and UV.
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| 13. |
- von Stedingk, Hans, et al.
(författare)
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A new modified Edman procedure for analysis of N-terminal valine adducts in hemoglobin by LC-MS/MS
- 2010
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Ingår i: Journal of chromatography. B. - : Elsevier BV. - 1570-0232 .- 1873-376X. ; 878:27, s. 2483-2490
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Tidskriftsartikel (refereegranskat)abstract
- A rapid and sensitive method using liquid chromatography-tandem mass spectrometry (LC-MS/MS) for simultaneous determination of adducts from acrylamide, glycidamide and ethylene oxide to N-terminal valines in hemoglobin (Hb) was developed. This new procedure is based on the same principles as the N-alkyl Edman procedure for analysis of adducts from electrophilic agents to N-terminal valines in Hb. The N-substituted valines can be detached, enriched and measured selectively as thiohydantoins by the use of an Edman reagent, in this case fluorescein isothiocyanate (FITC). This procedure is denoted as the "adduct FIRE procedure" as the FITC reagent is used for measurement of adducts ((R) under bar) formed from electrophilic compounds with a modified Edman procedure. In this study, fluorescein thiohydantoin (FTH) analytes of N-substituted valines from acrylamicle, glycidamide and ethylene oxide, as well as their corresponding hepta- and tri-deuterium-substituted analogues, were synthesized. These analytes (n = 8) were then characterized by LC-MS/MS (ESI, positive ion mode) and obtained product ions were interpreted. A considerable work with optimization of the FIRE procedure (TM), resulted in a procedure in which low background levels of the studied adducts could be measured from 250 mu L lyzed whole blood samples (human non-smokers). The analytes were enriched and purified with solid phase extraction columns and analyzed by LC-MS/MS with LOQ clown to 1 pmol adduct/g Hb. Compared to other procedures for determination of N-terminal Hb adducts, the introduction of FITC has led to a simplified procedure, where whole blood also can be used, giving new opportunities and reduced hand on time with increased sample throughput.
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| 14. |
- von Stedingk, Hans, 1978-, et al.
(författare)
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Analysis of hemoglobin adducts from acrylamide, glycidamide and ethylene oxide in paired mother/cordblood samples from Denmark
- 2011
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Ingår i: Chemical Research in Toxicology. - : American Chemical Society (ACS). - 0893-228X .- 1520-5010. ; 24:11, s. 1957-1965
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Tidskriftsartikel (refereegranskat)abstract
- The knowledge about fetal exposure to acrylamide/glycidamide from the maternal exposure through food is limited. Acrylamide, glycidamide, and ethylene oxide are electrophiles and form adducts with hemoglobin (Hb), which could be used for in vivo dose measurement. In this study, a method for analysis of Hb adducts by liquid chromatography–mass spectrometry, the adduct FIRE procedure, was applied to measurements of adducts from these compounds in maternal blood samples (n = 87) and umbilical cord blood samples (n = 219). The adduct levels from the three compounds, acrylamide, glycidamide, and ethylene oxide, were increased in tobacco smokers. Highly significant correlations were found between cord and maternal blood with regard to measured adduct levels of the three compounds. The mean cord/maternal hemoglobin adduct level ratios were 0.48 (range 0.27–0.86) for acrylamide, 0.38 (range 0.20–0.73) for glycidamide, and 0.43 (range 0.17–1.34) for ethylene oxide. In vitro studies with acrylamide and glycidamide showed a lower (0.38–0.48) rate of adduct formation with Hb in cord blood than with Hb in maternal blood, which is compatible with the structural differences in fetal and adult Hb. Together, these results indicate a similar life span of fetal and maternal erythrocytes. The results showed that the in vivo dose in fetal and maternal blood is about the same and that the placenta gives negligible protection of the fetus to exposure from the investigated compounds. A trend of higher levels of the measured adducts in cord blood with gestational age was observed, which may reflect the gestational age-related change of the cord blood Hb composition toward a higher content of adult Hb. The results suggest that the Hb adduct levels measured in cord blood reflect the exposure to the fetus during the third trimester. The evaluation of the new analytical method showed that it is suitable for monitoring of background exposures of the investigated electrophilic compounds in large population studies.
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| 15. |
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| 16. |
- von Stedingk, Hans, 1978-, et al.
(författare)
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Hemoglobin adducts
- 2011
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Ingår i: Biomarkers and Human Biomonitoring. Vol. 2 : Selected biomarkers of current interest. - Cambridge : Royal Society of Chemistry. - 9781849732420 - 1849732426 ; , s. 1-22
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Bokkapitel (övrigt vetenskapligt/konstnärligt)
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| 17. |
- von Stedingk, Hans, 1978-
(författare)
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Methodology for hemoglobin adduct measurement : Fetal exposures to acrylamide and other genotoxic agents
- 2011
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- There is increasing evidence that exposure to toxic chemicals during the prenatal period constitute a higher health risk than exposure during adulthood. To characterize exposure and identify risk factors, sensitive methods for analysis of chemicals in vivo with biomarker methods are needed. Adducts to hemoglobin (Hb) have been shown useful as biomarkers of dose in blood of reactive compounds/metabolites, which are toxic due to reactions with biomacromolecules. The aim of this thesis was to develop a new method for the analysis of Hb adducts suitable for analysis of large sample series, and then to apply the method for measurements of Hb adducts from exposure to acrylamide, glycidamide and ethylene oxide in mother/cord blood samples from five European countries. A new method for measurements of N-terminal Hb adducts, denoted the adduct FIRE procedure, was developed using the fluorescein isothiocyanate Edman reagent. With the new procedure, optimized for LC/MS analysis, a high sensitivity and reproducibility was achieved. The new method made it possible to perform measurements of low exposures to the studied genotoxic compounds in approximately 1350 maternal and cord blood samples. The results show that the fetus is exposed to a similar in vivo dose of the studied compounds as the mother. The measured Hb adduct levels show that acrylamide exposure from food intake is higher for the participating mothers fromUK compared to the mothers from the other countries. The measured Hb adduct levels form a basis for evaluations of relationships between exposure and health risks, and ongoing studies indicate associations between acrylamide Hb adduct levels and birth weight. The developed method was also used for identification of an unknown Hb adduct, which was shown to originate from methyl vinyl ketone (MVK), a highly reactive and toxic compound. The identity of the adduct was confirmed with synthesized standards. There exist both natural and anthropogenic sources to MVK, and to what extent the MVK-adduct reflects exogenous exposure is yet not clarified.
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| 18. |
- von Stedingk, Hans, et al.
(författare)
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Methyl vinyl ketone – identification and quantification of adduct to N-terminal valine in human haemoglobin
- 2010
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Ingår i: Journal of chromatography. B. - : Elsevier BV. - 1570-0232 .- 1873-376X. ; 878:27, s. 2491-2496
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Tidskriftsartikel (refereegranskat)abstract
- Adducts to N-terminal valines in Hb have been shown useful as biomarkers of exposure to electrophilic compounds. Adducts from many compounds have earlier been measured with a modified Edman degradation method using a GC–MS/MS method. A recently developed method, the adduct FIRE procedure™, adopted for analysis by LC–MS/MS, has been applied in this study. With this method a fluorescein isothiocyanate (FITC) reagent is used to measure adducts (R) from electrophiles with a modified Edman procedure. By using LC–MS/MS in product ion scan mode, a new peak was identified and the obtained MS data indicated that this adduct could originate from methyl vinyl ketone (MVK). Incubation of human-, sheep- and bovine blood with MVK increased the signal of the identified peak. By comparing the LC–MS/MS data from the unknown background peak with data obtained from synthesized fluorescein thiohydantoin (FTH) standards of the MVK adduct to valine and d8-valine, the identity of this adduct was confirmed. The MVK adduct was shown present in human blood (35 pmol/g globin, n = 3) and only just above LOD in bovine blood, n = 1 (LOD = 2 pmol/g globin). MVK reacts, in similarity with acrylamide, via Michael addition. MVK is known to occur in the environment and has earlier been observed in biological samples, which means that there are possible natural and anthropogenic exposure sources. Analysis of an Hb adduct from MVK in humans has to our knowledge not been described before.
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| 19. |
- von Stedingk, Hans, et al.
(författare)
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Validation of a novel procedure for quantification of the formation of phosphoramide mustard by individuals treated with cyclophosphamide
- 2014
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Ingår i: Cancer Chemotherapy and Pharmacology. - : Springer Science and Business Media LLC. - 0344-5704 .- 1432-0843. ; 74:3, s. 549-558
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Tidskriftsartikel (refereegranskat)abstract
- Use of the patient's body surface area (mg m(-2)) as a basis for dosing does not take individual variation in metabolic capacity and rate of clearance into account. Here, we evaluated a novel approach for individual monitoring of short-lived cytotoxic agents formed from cytostatic drugs such as cyclophosphamide (CP). The accumulated blood dose of the cytotoxic active agent phosphoramide mustard (PAM) formed from CP was measured as a reaction product with hemoglobin (Hb adduct). This adduct, N-[2-(2-oxazolidonyl)ethyl]-valyl Hb (OzVal-Hb), was detached from Hb with the adduct FIRE procedure (TM), and the formed analyte was quantified using LC-MS/MS. This dose biomarker for PAM and the analytical procedure was evaluated in accordance with the guidelines on bioanalytical method validation formulated by the European Medicine Agency. The evaluated method was applied to quantify blood dose levels of PAM in female breast cancer patients (n = 12) before and after three cycles of polychemotherapy regimes containing CP. OzVal-Hb, a specific and stable biomarker, could be measured with great sensitivity (lower limit of quantification = 33 pmol g(-1) Hb), high accuracy (within +/- 20 %) and good repeatability (CV < 20 %). The inter-individual variability in the blood level of this adduct in women with breast cancer (n = 12) who received three doses of CP in combination with one or two other cytostatic drugs was 250 % following the first dose and approximately 150 % after each subsequent dose. Measurement of the biomarker OzVal-Hb can be used to quantify the short-lived cytotoxic agent PAM in a single blood sample drawn several days after therapy. This procedure may aid in individualizing doses of CP, thereby improving efficacy while both reducing the risk of and increasing the predictability of side-effects.
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