| 1. |
- Aad, G., et al.
(författare)
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- 2011
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swepub:Mat__t (refereegranskat)
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| 2. |
- Bogdanska, Jasna, et al.
(författare)
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Tissue distribution of (35)S-labelled perfluorooctane sulfonate in adult mice after oral exposure to a low environmentally relevant dose or a high experimental dose
- 2011
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Ingår i: Toxicology. - : Elsevier BV. - 0300-483X .- 1879-3185. ; 284:1-3, s. 54-62
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Tidskriftsartikel (refereegranskat)abstract
- The widespread environmental pollutant perfluorooctane sulfonate (PFOS), detected in most animal species including the general human population, exerts several effects on experimental animals, e.g., hepatotoxicity, immunotoxicity and developmental toxicity. However, detailed information on the tissue distribution of PFOS in mammals is scarce and, in particular, the lack of available information regarding environmentally relevant exposure levels limits our understanding of how mammals (including humans) may be affected. Accordingly, we characterized the tissue distribution of this compound in mice, an important experimental animal for studying PFOS toxicity. Following dietary exposure of adult male C57/BL6 mice for 1-5 days to an environmentally relevant (0.031 mg/kg/day) or a 750-fold higher experimentally relevant dose (23 mg/kg/day) of (35)S-PFOS, most of the radioactivity administered was recovered in liver, bone (bone marrow), blood, skin and muscle, with the highest levels detected in liver, lung, blood, kidney and bone (bone marrow). Following high daily dose exposure, PFOS exhibited a different distribution profile than with low daily dose exposure, which indicated a shift in distribution from the blood to the tissues with increasing dose. Both scintillation counting (with correction for the blood present in the tissues) and whole-body autoradiography revealed the presence of PFOS in all 19 tissues examined, with identification of thymus as a novel site for localization for PFOS and bone (bone marrow), skin and muscle as significant body compartments for PFOS. These findings demonstrate that PFOS leaves the bloodstream and enters most tissues in a dose-dependent manner.
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| 3. |
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| 4. |
- Dunham, I, et al.
(författare)
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The DNA sequence of human chromosome 22
- 1999
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Ingår i: Nature. - : Springer Science and Business Media LLC. - 0028-0836 .- 1476-4687. ; 402:6761, s. 489-495
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Tidskriftsartikel (refereegranskat)
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| 5. |
- Kretova, Miroslava, et al.
(författare)
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TGF-beta/NF1/Smad4-mediated suppression of ANT2 contributes to oxidative stress in cellular senescence
- 2014
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Ingår i: Cellular Signalling. - : Elsevier BV. - 0898-6568 .- 1873-3913. ; 26:12, s. 2903-2911
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Tidskriftsartikel (refereegranskat)abstract
- Oxidative stress and persistent activation of DNA damage response (DDR) are causally involved in the development of cellular senescence, a phenomenon implicated in fundamental (patho)physiological processes such as aging, fetal development and tumorigenesis. Here, we report that adenine nucleotide translocase-2 (ANT2) is consistently down-regulated in all three major forms of cellular senescence: replicative, oncogene-induced and drug-induced, in both normal and cancerous human cells. We previously reported formation of novel NF1/Smad transcription repressor complexes in growth-arrested fibroblasts. Here we show that such complexes form in senescent cells. Mechanistically, binding of the NF1/Smad complexes to the NF1-dependent repressor elements in the ANT2 gene promoter repressed ANT2 expression. Etoposide-induced formation of these complexes and repression of ANT2 were relatively late events co-incident with production and secretion of, and dependent on, TGF-beta. siRNA-mediated knock-down of ANT2 in proliferating cells resulted in increased levels of reactive oxygen species (ROS) and activation of the DDR. Knock-down of ANT2, together with etoposide treatment, further intensified ROS production and DNA damage signaling, leading to enhanced apoptosis. Together, our data show that TGF-beta-mediated suppression of ANT2 through NF1/Smad4 complexes contributes to oxidative stress and DNA damage during induction of cellular senescence.
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| 6. |
- Qazi, Mousumi Rahman, et al.
(författare)
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Characterization of the Hepatic and Splenic Immune Status and Immunoglobulin Synthesis in Aged Male Mice Lacking the Peroxisome Proliferator-Activated Receptor-Alpha (PPAR alpha)
- 2011
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Ingår i: Scandinavian Journal of Immunology. - : Wiley. - 0300-9475 .- 1365-3083. ; 73:3, s. 198-207
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Tidskriftsartikel (refereegranskat)abstract
- It is now well established that the nuclear receptor peroxisome proliferator-activated receptor-alpha (PPAR alpha) is expressed in different types of immune cells and plays a pivotal role in the regulation of age-related production of inflammatory cytokines. However, the role(s) of this receptor in the regulation of immune cell homoeostasis in ageing non-lymphoid and lymphoid organs has not yet been resolved. We examine this issue here by evaluating the hepatic and splenic immune status and immunoglobulin (Ig) production in male PPAR alpha-null mice and their wild-type littermates at one and 2 years of age. In comparison with the age-matched control animals, PPAR alpha-null mice exhibited age-related elevations in the numbers of total, as well as of phenotypically distinct subpopulations of intrahepatic immune cells (IHIC) and splenocytes. Moreover, at 2 years of age, these alterations in hepatic immune cells were accompanied by significant increases in hepatic levels of the pro-inflammatory cytokines tumour necrosis factor-alpha (TNF-alpha), interleukin-6 (IL-6) and interferon-gamma (IFN-gamma), in combination with the development of hepatic inflammatory loci containing mixtures of leucocytes. Alterations in splenocytes of old PPAR alpha-null mice were also accompanied by increases in cellularity of both white and red pulps of the spleen. Furthermore, these same animals exhibited pronounced increases in the numbers of splenic plasma cells and enhanced production of Ig of different isotypes, including IgG1, IgG2a and IgE. Thus, our findings indicate that upon ageing, PPAR alpha plays a crucial role in regulating the total numbers, compositions and functions of immune cells in both lymphoid and non-lymphoid immune organs of mice.
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| 7. |
- Qazi, Mousumi Rahman, et al.
(författare)
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High-dose dietary exposure of mice to perfluorooctanoate or perfluorooctane sulfonate exerts toxic effects on myeloid and B-lymphoid cells in the bone marrow and these effects are partially dependent on reduced food Consumption
- 2012
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Ingår i: Food and Chemical Toxicology. - : Elsevier BV. - 0278-6915 .- 1873-6351. ; 50:9, s. 2955-2963
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Tidskriftsartikel (refereegranskat)abstract
- It is well established that exposure of mice to perfluorooctanoate (PFOA) or perfluorooctane sulfonate (PFOS) exerts adverse effects on the thymus and spleen. Here, we characterize the effects of a 10-day dietary treatment with these compounds (0.001-0.02%, w/w) on the bone marrow (BM) of mice. At a dose of 0.02%, both compounds reduced food consumption and caused atrophy of the thymus and spleen. At this same dose, histopathological and flow cytometric analysis revealed that (i) the total numbers of BM as well as the numbers of myeloid, pro/pre B, immature B and early mature B cells were all reduced significantly; and (ii) these adverse effects were reversed either partially or completely 10 days after withdrawal of these compounds. At the lower dose of 0.002%, only PFOA reduced the B-lymphoid cell population. Finally, mice fed an amount of diet equivalent to that consumed by the animals exposed to 0.02% PFOA also exhibited atrophy of the thymus and spleen, and a reduction in the number of B-lymphoid population, without affecting myeloid cells. Thus, in mice, immunotoxic doses of PFOA or PFOS induce adverse effects on the myeloid and B-lymphoid cells in the BM, in part as a consequence of reduced food consumption.
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