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- Bonefeld-Jorgensen, Eva C, et al.
(författare)
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Xenoestrogenic activity in blood of European and Inuit populations
- 2006
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Ingår i: Environmental Health. - 1476-069X. ; 5:12
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Human exposure to persistent organic pollutants (POPs) is ubiquitous and found in all individuals. Studies have documented endocrine disrupting effects and impact on reproduction. The aim of the present study was to compare the level of xenoestrogenic activity in serum of groups with varying POP exposure, and to evaluate correlations to the POP biomarkers, 2,2',4,4',5,5'-hexachlorobiphenyl (CB-153) and 1,1-dichloro-2,2-bis (p-chlorophenyl)-ethylene (p,p'-DDE). METHODS: The study included 358 men: Greenlandic Inuit's, Swedish fishermen, and Warsaw (Poland) and Kharkiv (Ukraine) inhabitants. Xenoestrogenicity of serum extracts alone (XER) and XER competitive (XERcomp) effect on 17beta-estradiol induced estrogen receptor (ER) transactivity were assessed in the hormone free, lipophilic serum fraction containing the POPs using the MVLN human breast cancer cell line. RESULTS: No agonistic XER activity was exhibited for Inuit serum samples, while 12 - 24% of the European samples had detectable agonistic XER activity. On the contrary, 71% of Inuit serum samples antagonized XERcomp compared to 7 - 30 % in the other regions. XER and XERcomp were not or weakly correlated to the two POP markers. XER activity of Inuit samples was negatively associated to levels of CB-153 and p,p'-DDE. For the Warsaw group a positive and negative correlation between XER and p,p'-DDE and estradiol equivalence level and CB-153 levels was found. CONCLUSION: No strong consistent association between xenoestrogenic net activity and the two POP markers was found. The results showed that the selected POP markers alone can not predict the integrated xenoestrogenic serum activity. Correlations to the POP markers were found at the extreme edge; the Inuit's and Warsaw study groups eliciting high frequency of samples with ER antagonistic and agonistic activity, respectively. We suggest that the variation in xenoestrogenic serum activity reflects differences in POP exposure mixture, genetic factors and/or life style factors.
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- Bungum, Mona, et al.
(författare)
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Sperm chromatin structure assay parameters measured after density gradient centrifugation are not predictive for the outcome of ART
- 2008
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Ingår i: Human Reproduction. - : Oxford University Press (OUP). - 0268-1161 .- 1460-2350. ; 23:1, s. 41374-41374
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND The sperm chromatin structure assay (SCSA) parameter DNA fragmentation index (DFI) has been shown to predict in vivo and in vitro fertility. So far most SCSA studies have been based on SCSA analysis performed on neat semen. The aim of this study is to assess whether SCSA analysis of sperm prepared by density gradient centrifugation (DGC) could add more information in regard to the prediction of treatment outcome. METHODS The study included 510 assisted reproductive technique (ART) cycles. SCSA was performed in neat semen and post DGC. SCSA results were expressed in terms of DFI and high DNA stainability (HDS) cell fractions. The outcome parameter was clinical pregnancy (CP). RESULTS Scatter-plot diagrams demonstrated that for DGC samples, no DFI cut-off values could be set for in vivo or in vitro fertility. In intrauterine insemination, IVF and ICSI groups the mean difference (95% CI) in DFI post DGC between those who achieved CP and those who did not was 0.2% (-1.7 to 2.0%), 0.4% (-1.9 to 2.8%) and 1.3% (-3.1 to 5.9%), respectively, none of these being statistically significant. The corresponding differences for HDS were 0.1% (-1.3 to 1.5%), 0.1% (-0.7 to 0.9%) and 0.6% (-1.6 to 2.7%), respectively (all P-values >0.6). CONCLUSIONS SCSA performed in semen prepared by DGC cannot predict the outcome of ART.
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- Consales, Claudia, et al.
(författare)
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Exposure to persistent organic pollutants and sperm DNA methylation changes in Arctic and European populations.
- 2016
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Ingår i: Environmental and Molecular Mutagenesis. - : Wiley. - 1098-2280 .- 0893-6692. ; 57:3, s. 200-209
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Tidskriftsartikel (refereegranskat)abstract
- Persistent organic pollutants (POPs), such as PCBs (polychlorinated biphenyls) and DDT [1,1,1-trichloro-2,2-bis(4-chlorophenyl)ethane], are environmental contaminants with potential endocrine disrupting activity. DNA methylation levels in peripheral blood lymphocytes have been associated with serum concentrations of POPs in Greenland Inuit and Korean populations. Greenland Inuits are characterized by the highest worldwide POP levels. In this cross-sectional study we evaluated the relationship between serum POP concentrations and DNA methylation levels in sperm of non-occupationally exposed fertile men from Greenland, Warsaw (Poland), and Kharkiv (Ukraine). Serum levels of PCB-153 [1,2,4-trichloro-5-(2,4,5-trichlorophenyl)benzene], as a proxy of the total PCBs body burden, and of p,p'-DDE [1,1-dichloro-2,2-bis(4-chlorophenyl)ethylene], the main metabolite of DDT were measured. Sperm DNA methylation level was assessed globally by flow cytometric (FCM) immunodetection of 5-methyl-cytosines and at specific repetitive DNA sequences (Alu, LINE-1, Satα) by PCR-pyrosequencing after bisulfite conversion. Multivariate linear regression analysis was applied to investigate correlations between serum POP concentrations and DNA methylation. No consistent associations between exposure to POPs and sperm DNA methylation at repetitive DNA sequences were detected. A statistically significant global decrease in methylation was associated with exposure to either POP by FCM analysis. This is the first study to investigate environmental exposure to POPs and DNA methylation levels considering sperm as the target cells. Although POP exposure appears to have a limited negative impact on sperm DNA methylation levels in adult males, the global hypomethylation detected by one of the methods applied suggests that further investigation is warranted. Environ. Mol. Mutagen., 2015. © 2015 Wiley Periodicals, Inc.
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- Giwercman, Aleksander, et al.
(författare)
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Androgen receptor gene CAG repeat length as a modifier of the association between persistent organohalogen pollutant exposure markers and semen characteristics
- 2007
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Ingår i: Pharmacogenetics & Genomics. - : Ovid Technologies (Wolters Kluwer Health). - 1744-6872. ; 17:6, s. 391-401
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Tidskriftsartikel (refereegranskat)abstract
- Objectives Exposure to persistent organohalogen pollutants was suggested to impair male reproductive function. A gene-environment interaction has been proposed. No genes modifying the effect of persistent organohalogen pollutants on reproductive organs have yet been identified. We aimed to investigate whether the CAG and GGN polymorphisms in the androgen receptor gene modify the effect of persistent organohalogen pollutant exposure on human sperm characteristics. Methods Semen and blood from 680 men [mean (SD) age 34 (10) years] from Greenland, Sweden, Warsaw (Poland) and Kharkiv (Ukraine) were collected. Persistent organohalogen pollutant exposure was assessed by measuring serum levels of 2,2,4,4,5,5'-hexachlorobiphenyl (CB-153) and dichlorodiphenyl dichloroethene (p,p'-DDE). Semen characteristics (volume, sperm concentration, total count proportion of progressively motile and morphology) and DNA fragmentation index (DFI) were determined. CAG and GGN repeat lengths were determined by direct sequencing of leukocyte DNA. Results A statistically significant interaction was found between the CB-153 group and CAG repeat category in relation to sperm concentration and total sperm count (P=0.03 and 0.01, respectively). For p,p'-DDE, in the European cohorts a significant interaction was found in relation to DFI (P=0.01). For CAG<20, sperm concentration and total sperm count were 35 and 42% lower, respectively, when the group with CB-153 exposure above median was compared with that below the median. DF1 was 40% higher in the high p,p'-DDE exposure group for CAG < 21. Conclusions This study indicated that the androgen receptor CAG repeat length might modify the susceptibility of an individual to the adverse effects of persistent organohalogen pollutant exposure on semen quality. Other studies regarding this matter are warranted.
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| 10. |
- Giwercman, Aleksander, et al.
(författare)
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Sperm chromatin structure assay as an independent predictor of fertility in vivo: a case-control study.
- 2010
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Ingår i: International Journal of Andrology. - : Wiley. - 1365-2605 .- 0105-6263. ; 33, s. 221-227
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Tidskriftsartikel (refereegranskat)abstract
- Summary Standard sperm parameters have a limited power for prediction of the chance of natural conception. Recent studies have indicated that the sperm chromatin structure assay (SCSA) DNA fragmentation index (DFI), a measure for the fraction of sperms with DNA damage, is associated with fertility in vivo. The aim of this study was to evaluate the value of this parameter for prediction of infertility. One hundred and twenty-seven men from infertile couples with no known female factor and 137 men with proven fertility were included. Semen analysis was performed as recommended by the WHO. DFI was assessed using SCSA. Logistic binary regression was used to compute the odds ratios (OR) for infertility. As compared with men with a DFI <10%, men with a DFI between 10% and 20% had an increased risk for infertility (OR 2.5, 95% CI: 1.0-6.1). This was also true for men with a DFI >20% (OR 8.4; 95% CI: 3.0-23). In men with normal standard semen parameters (sperm concentration, motility and morphology) the OR for infertility was increased with DFI >20% (OR 5.1, 95% CI: 1.2-23), whereas if one of the standard semen parameters was abnormal, the OR for infertility was increased already at DFI above 10% (OR 16, 95% CI: 4.2-60). We conclude that SCSA DFI adds to the value of semen analysis in prediction of the chance of natural conception.
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