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  1. Article ; Online: MosSCI-mediated exogenous gene expression is modulated by genomic positioning.

    Chen, Yuzhi / Arlt, Volker M / Stürzenbaum, Stephen R

    Biotechnology journal

    2023  Volume 18, Issue 9, Page(s) e2300062

    Abstract: Although the Mos1-mediated single-copy insertion (MosSCI) technique has been widely used to generate stable transgenic Caenorhabditis elegans strains, the link between stability of expression and integration site still needs to be explored. Here, ... ...

    Abstract Although the Mos1-mediated single-copy insertion (MosSCI) technique has been widely used to generate stable transgenic Caenorhabditis elegans strains, the link between stability of expression and integration site still needs to be explored. Here, experimental evidence is provided that transgenes are not able to match the level of transcription of their native counterpart, and that insertions at certain locations can result in an external stress-mediated increase in expression. Insertion site ttTi5605 on chromosome II was shown to be a superior location, at least when introducing reproduction related genes. Thus, this study provides a reference for the selection of an optimal site for MosSCI which provides acceptable expression performance whilst minimizing undesirable secondary effects.
    MeSH term(s) Animals ; Animals, Genetically Modified/genetics ; Mutagenesis, Insertional ; Genome ; Transgenes/genetics ; Caenorhabditis elegans/genetics ; Caenorhabditis elegans/metabolism ; Genomics ; Gene Expression
    Language English
    Publishing date 2023-05-22
    Publishing country Germany
    Document type Journal Article
    ZDB-ID 2221885-3
    ISSN 1860-7314 ; 1860-6768
    ISSN (online) 1860-7314
    ISSN 1860-6768
    DOI 10.1002/biot.202300062
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  2. Article ; Online: Stage-specific exposure of Caenorhabditis elegans to cadmium identifies unique transcriptomic response cascades and an uncharacterised cadmium responsive transcript.

    Almutairi, Norah / Khan, Naema / Harrison-Smith, Alexandra / Arlt, Volker M / Stürzenbaum, Stephen R

    Metallomics : integrated biometal science

    2024  

    Abstract: Age/stage sensitivity is considered a significant factor in toxicity assessments. Previous studies investigated cadmium (Cd) toxicosis in Caenorhabditis elegans, and a plethora of metal-responsive genes/proteins have been identified and characterised in ... ...

    Abstract Age/stage sensitivity is considered a significant factor in toxicity assessments. Previous studies investigated cadmium (Cd) toxicosis in Caenorhabditis elegans, and a plethora of metal-responsive genes/proteins have been identified and characterised in fine detail; however, most of these studies neglected age sensitivity and stage-specific response to toxicants at the molecular level. This present study compared the transcriptome response between C. elegans L3 vs L4 larvae exposed to 20 µM Cd to explore the transcriptional hallmarks of stage sensitivity. The results showed that the transcriptome of the L3 stage, despite being exposed to Cd for a shorter period, was more affected than the L4 stage, as demonstrated by differences in transcriptional changes and magnitude of induction. Additionally, T08G5.1, a hitherto uncharacterised gene located upstream of metallothionein (mtl-2), was transcriptionally hyperresponsive to Cd exposure. Deletion of one or both metallothioneins (mtl-1 and/or mtl-2) increased T08G5.1 expression, suggesting that its expression is linked to the loss of metallothionein. The generation of an extrachromosomal transgene (PT08G5.1:: GFP) revealed that T08G5.1 is constitutively expressed in the head neurons and induced in gut cells upon Cd exposure, not unlike mtl-1 and mtl-2. The low abundance of cysteine residues in T08G5.1 suggests, however, that it may not be involved directly in Cd sequestration to limit its toxicity like metallothionein, but might be associated with a parallel pathway, possibly an oxidative stress response.
    Language English
    Publishing date 2024-03-28
    Publishing country England
    Document type Journal Article
    ZDB-ID 2474317-3
    ISSN 1756-591X ; 1756-5901
    ISSN (online) 1756-591X
    ISSN 1756-5901
    DOI 10.1093/mtomcs/mfae016
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  3. Article ; Online: 32

    Phillips, David H / Arlt, Volker M

    Methods in molecular biology (Clifton, N.J.)

    2020  Volume 2102, Page(s) 291–302

    Abstract: ... ...

    Abstract 32
    MeSH term(s) Animals ; Carcinogens/chemistry ; Carcinogens/toxicity ; Chromatography, High Pressure Liquid/methods ; DNA Adducts/analysis ; DNA Adducts/chemistry ; DNA Adducts/genetics ; DNA Damage/drug effects ; Fungal Proteins ; Humans ; Isotope Labeling/methods ; Mutagens/chemistry ; Mutagens/toxicity ; Oxidative Stress/genetics ; Phosphorus Radioisotopes ; Phosphotransferases ; Single-Strand Specific DNA and RNA Endonucleases ; Workflow
    Chemical Substances Carcinogens ; DNA Adducts ; Fungal Proteins ; Mutagens ; Phosphorus Radioisotopes ; Phosphotransferases (EC 2.7.-) ; Nuclease P1, Penicillium citrinum (EC 3.1.30.1) ; Single-Strand Specific DNA and RNA Endonucleases (EC 3.1.30.1)
    Language English
    Publishing date 2020-01-17
    Publishing country United States
    Document type Journal Article
    ISSN 1940-6029
    ISSN (online) 1940-6029
    DOI 10.1007/978-1-0716-0223-2_16
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  4. Article ; Online: Benzo[a]pyrene and Caenorhabditis elegans: defining the genotoxic potential in an organism lacking the classical CYP1A1 pathway.

    Abbass, Mustafa / Chen, Yuzhi / Arlt, Volker M / Stürzenbaum, Stephen R

    Archives of toxicology

    2021  Volume 95, Issue 3, Page(s) 1055–1069

    Abstract: Benzo[a]pyrene (BaP) is bioactivated in most organisms by the cytochrome P450 (CYP) enzymes, mainly CYP1A1, ultimately resulting in the reactive metabolite BaP-7,8-dihydrodiol-9,10-epoxide (BPDE) capable of covalently binding to DNA and forming adducts. ... ...

    Abstract Benzo[a]pyrene (BaP) is bioactivated in most organisms by the cytochrome P450 (CYP) enzymes, mainly CYP1A1, ultimately resulting in the reactive metabolite BaP-7,8-dihydrodiol-9,10-epoxide (BPDE) capable of covalently binding to DNA and forming adducts. This step has been defined as the key process in cancer initiation in humans. However, limited knowledge is available about the consequences of BaP exposure in organisms lacking this classical CYP1A1 pathway, one example is the model nematode Caenorhabditis elegans. The aim of this study was to define the genotoxic potential of BaP in C. elegans and to advance our understanding of xenobiotic processing in the absence of the CYP1A1 pathway. Exposure to high concentrations of BaP (0-40 µM) significantly affected life cycle endpoints of C. elegans, which were manifested by a reduced reproductive output and shortened life span. An optimised comet assay revealed that DNA damage increased in a dose-dependent manner; however, no bulky DNA adducts (dG-N
    MeSH term(s) Animals ; Benzo(a)pyrene/administration & dosage ; Benzo(a)pyrene/metabolism ; Benzo(a)pyrene/toxicity ; Caenorhabditis elegans/drug effects ; Caenorhabditis elegans/genetics ; Caenorhabditis elegans Proteins/genetics ; Comet Assay ; Cytochrome P-450 CYP1A1/metabolism ; Cytochrome P-450 Enzyme System/genetics ; DNA Damage/drug effects ; Disease Models, Animal ; Dose-Response Relationship, Drug ; Mutagenicity Tests ; Mutagens/administration & dosage ; Mutagens/toxicity
    Chemical Substances CYP35 protein, C elegans ; Caenorhabditis elegans Proteins ; Mutagens ; Benzo(a)pyrene (3417WMA06D) ; Cytochrome P-450 Enzyme System (9035-51-2) ; Cytochrome P-450 CYP1A1 (EC 1.14.14.1)
    Language English
    Publishing date 2021-01-09
    Publishing country Germany
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 124992-7
    ISSN 1432-0738 ; 0340-5761
    ISSN (online) 1432-0738
    ISSN 0340-5761
    DOI 10.1007/s00204-020-02968-z
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  5. Article ; Online: Organoids for toxicology and genetic toxicology: applications with drugs and prospects for environmental carcinogenesis.

    Caipa Garcia, Angela L / Arlt, Volker M / Phillips, David H

    Mutagenesis

    2021  Volume 37, Issue 2, Page(s) 143–154

    Abstract: Advances in three-dimensional (3D) cell culture technology have led to the development of more biologically and physiologically relevant models to study organ development, disease, toxicology and drug screening. Organoids have been derived from many ... ...

    Abstract Advances in three-dimensional (3D) cell culture technology have led to the development of more biologically and physiologically relevant models to study organ development, disease, toxicology and drug screening. Organoids have been derived from many mammalian tissues, both normal and tumour, from adult stem cells and from pluripotent stem cells. Tissue organoids can retain many of the cell types and much of the structure and function of the organ of origin. Organoids derived from pluripotent stem cells display increased complexity compared with organoids derived from adult stem cells. It has been shown that organoids express many functional xenobiotic-metabolising enzymes including cytochrome P450s (CYPs). This has benefitted the drug development field in facilitating pre-clinical testing of more personalised treatments and in developing large toxicity and efficacy screens for a range of compounds. In the field of environmental and genetic toxicology, treatment of organoids with various compounds has generated responses that are close to those obtained in primary tissues and in vivo models, demonstrating the biological relevance of these in vitro multicellular 3D systems. Toxicological investigations of compounds in different tissue organoids have produced promising results indicating that organoids will refine future studies on the effects of environmental exposures and carcinogenic risk to humans. With further development and standardised procedures, advancing our understanding on the metabolic capabilities of organoids will help to validate their use to investigate the modes of action of environmental carcinogens.
    MeSH term(s) Animals ; Carcinogenesis ; Cell Culture Techniques ; Humans ; Mammals ; Models, Biological ; Organoids ; Pluripotent Stem Cells
    Language English
    Publishing date 2021-06-19
    Publishing country England
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 632903-2
    ISSN 1464-3804 ; 0267-8357
    ISSN (online) 1464-3804
    ISSN 0267-8357
    DOI 10.1093/mutage/geab023
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  6. Article ; Online: Environmental carcinogen benzo[a]pyrene alters neutral lipid storage via a cyp-35A2 mediated pathway in Caenorhabditis elegans.

    Chen, Yuzhi / Abbass, Mustafa / Brock, Trisha / Hobbs, Gian / Ciufo, Leonardo A / Hopkins, Christopher / Arlt, Volker M / Stürzenbaum, Stephen R

    Environmental pollution (Barking, Essex : 1987)

    2023  Volume 339, Page(s) 122731

    Abstract: Polycyclic aromatic hydrocarbons (PAHs), in particular benzo [a]pyrene (BaP), have been identified as carcinogenic components of tobacco smoke. In mammals, the toxicological response to BaP-diol-epoxide is driven by cytochrome P450 (CYP1A1), a pathway ... ...

    Abstract Polycyclic aromatic hydrocarbons (PAHs), in particular benzo [a]pyrene (BaP), have been identified as carcinogenic components of tobacco smoke. In mammals, the toxicological response to BaP-diol-epoxide is driven by cytochrome P450 (CYP1A1), a pathway which is absent in Caenorhabditis elegans. In contrast, in worms prominently the CYP-35 enzyme family seems to be induced after BaP exposure. In C. elegans, BaP exposure reduces the accumulation of lysosomal neutral lipids in a dose dependent manner and the deletion of cyp-35A2 results in a significant elevation of neutral lipid metabolism. A cyp-35A2:mCherry;unc-47:GFP dual-labelled reporter strain facilitated the identification of three potential upstream regulators that drive BaP metabolism in worms, namely elt-2, nhr-49 and fos-1. This newly described reporter line is a powerful resource for future large-scale RNAi regarding toxicology and lipid metabolism screens.
    MeSH term(s) Animals ; Benzo(a)pyrene/toxicity ; Benzo(a)pyrene/metabolism ; Caenorhabditis elegans/metabolism ; Carcinogens, Environmental ; Cytochrome P-450 Enzyme System/metabolism ; Cytochrome P-450 CYP1A1/metabolism ; Lipids ; Mammals/metabolism ; Caenorhabditis elegans Proteins/genetics ; Caenorhabditis elegans Proteins/metabolism ; Vesicular Inhibitory Amino Acid Transport Proteins
    Chemical Substances Benzo(a)pyrene (3417WMA06D) ; Carcinogens, Environmental ; Cytochrome P-450 Enzyme System (9035-51-2) ; Cytochrome P-450 CYP1A1 (EC 1.14.14.1) ; Lipids ; unc-47 protein, C elegans ; Caenorhabditis elegans Proteins ; Vesicular Inhibitory Amino Acid Transport Proteins
    Language English
    Publishing date 2023-10-13
    Publishing country England
    Document type Journal Article
    ZDB-ID 280652-6
    ISSN 1873-6424 ; 0013-9327 ; 0269-7491
    ISSN (online) 1873-6424
    ISSN 0013-9327 ; 0269-7491
    DOI 10.1016/j.envpol.2023.122731
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  7. Article ; Online: Tissue Organoid Cultures Metabolize Dietary Carcinogens Proficiently and Are Effective Models for DNA Adduct Formation.

    Caipa Garcia, Angela L / Kucab, Jill E / Al-Serori, Halh / Beck, Rebekah S S / Bellamri, Madjda / Turesky, Robert J / Groopman, John D / Francies, Hayley E / Garnett, Mathew J / Huch, Meritxell / Drost, Jarno / Zilbauer, Matthias / Arlt, Volker M / Phillips, David H

    Chemical research in toxicology

    2024  Volume 37, Issue 2, Page(s) 234–247

    Abstract: Human tissue three-dimensional (3D) organoid cultures have the potential to ... ...

    Abstract Human tissue three-dimensional (3D) organoid cultures have the potential to reproduce
    MeSH term(s) Humans ; DNA Adducts ; Carcinogens/toxicity ; Carcinogens/metabolism ; Neoplasms ; Liver/metabolism ; Organoids/metabolism
    Chemical Substances DNA Adducts ; Carcinogens
    Language English
    Publishing date 2024-01-17
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 639353-6
    ISSN 1520-5010 ; 0893-228X
    ISSN (online) 1520-5010
    ISSN 0893-228X
    DOI 10.1021/acs.chemrestox.3c00255
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  8. Article ; Online: Enhanced DNA adduct formation by benzo[a]pyrene in human liver cells lacking cytochrome P450 oxidoreductase.

    Reed, Lindsay / Jarvis, Ian W H / Phillips, David H / Arlt, Volker M

    Mutation research

    2020  Volume 852, Page(s) 503162

    Abstract: Diet is a major source of human exposure to polycyclic aromatic hydrocarbons (PAHs), of which benzo[a]pyrene (BaP) is the most commonly studied and measured. BaP has been considered to exert its genotoxic effects after metabolic activation by cytochrome ... ...

    Abstract Diet is a major source of human exposure to polycyclic aromatic hydrocarbons (PAHs), of which benzo[a]pyrene (BaP) is the most commonly studied and measured. BaP has been considered to exert its genotoxic effects after metabolic activation by cytochrome P450 (CYP) enzymes whose activity can be modulated by cytochrome P450 oxidoreductase (POR), the electron donor to CYP enzymes. Previous studies showed that BaP-DNA adduct formation was greater in the livers of Hepatic Reductase Null (HRN) mice, in which POR is deleted specifically in hepatocytes, than in wild-type (WT) mice. In the present study we used human hepatoma HepG2 cells carrying a knockout (KO) in the POR gene as a human in vitro model that can mimic the HRN mouse model. Treatment to BaP for up to 48 h caused similar cytotoxicity in POR KO and WT HepG2 cells. However, levels of BaP activation (i.e. BaP-7,8-dihydrodiol formation) were higher in POR KO HepG2 cells than in WT HepG2 cells after 48 h. This also resulted in substantially higher BaP-DNA adduct formation in POR KO HepG2 cells indicating that BaP metabolism is delayed in POR KO HepG2 cells thereby prolonging the effective exposure of cells to unmetabolized BaP. As was seen in the HRN mouse model, these results suggest that cytochrome b
    MeSH term(s) Benzo(a)pyrene/chemistry ; Benzo(a)pyrene/metabolism ; Benzo(a)pyrene/toxicity ; Carcinogens/toxicity ; Cell Survival/drug effects ; Cytochrome P-450 Enzyme System/deficiency ; Cytochrome P-450 Enzyme System/genetics ; DNA Adducts/agonists ; DNA Adducts/chemistry ; DNA Adducts/metabolism ; DNA Damage ; Dose-Response Relationship, Drug ; Gene Expression ; Gene Knockout Techniques ; Hep G2 Cells ; Humans
    Chemical Substances Carcinogens ; DNA Adducts ; POR protein, human ; benzo(a)pyrene-DNA adduct ; Benzo(a)pyrene (3417WMA06D) ; Cytochrome P-450 Enzyme System (9035-51-2)
    Language English
    Publishing date 2020-02-22
    Publishing country Netherlands
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 206607-5
    ISSN 1873-135X ; 1383-5718 ; 0027-5107 ; 0165-1110 ; 0165-1161 ; 0165-7992 ; 0921-8777 ; 0165-1218 ; 1383-5726 ; 0167-8817 ; 0921-8734 ; 1383-5742
    ISSN (online) 1873-135X
    ISSN 1383-5718 ; 0027-5107 ; 0165-1110 ; 0165-1161 ; 0165-7992 ; 0921-8777 ; 0165-1218 ; 1383-5726 ; 0167-8817 ; 0921-8734 ; 1383-5742
    DOI 10.1016/j.mrgentox.2020.503162
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  9. Article ; Online: The Impact of p53 on Aristolochic Acid I-Induced Gene Expression In Vivo.

    Sborchia, Mateja / Keun, Hector C / Phillips, David H / Arlt, Volker M

    International journal of molecular sciences

    2019  Volume 20, Issue 24

    Abstract: Exposure to aristolochic acid (AA) is linked to kidney disease and urothelial cancer in humans. The major carcinogenic component of the AA plant extract is aristolochic acid I (AAI). The tumour suppressor p53 is frequently mutated in AA-induced tumours. ... ...

    Abstract Exposure to aristolochic acid (AA) is linked to kidney disease and urothelial cancer in humans. The major carcinogenic component of the AA plant extract is aristolochic acid I (AAI). The tumour suppressor p53 is frequently mutated in AA-induced tumours. We previously showed that p53 protects from AAI-induced renal proximal tubular injury, but the underlying mechanism(s) involved remain to be further explored. In the present study, we investigated the impact of p53 on AAI-induced gene expression by treating
    MeSH term(s) Animals ; Aristolochic Acids/pharmacology ; Genotype ; Kidney/drug effects ; Kidney/metabolism ; Male ; Mice ; Proteomics/methods ; Signal Transduction/drug effects ; Signal Transduction/genetics ; Tumor Suppressor Protein p53/genetics ; Tumor Suppressor Protein p53/metabolism
    Chemical Substances Aristolochic Acids ; Tumor Suppressor Protein p53 ; aristolochic acid I (94218WFP5T)
    Language English
    Publishing date 2019-12-06
    Publishing country Switzerland
    Document type Journal Article
    ZDB-ID 2019364-6
    ISSN 1422-0067 ; 1422-0067 ; 1661-6596
    ISSN (online) 1422-0067
    ISSN 1422-0067 ; 1661-6596
    DOI 10.3390/ijms20246155
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  10. Article ; Online: The role of cytochrome P450 enzymes in carcinogen activation and detoxication: an in vivo-in vitro paradox.

    Reed, Lindsay / Arlt, Volker M / Phillips, David H

    Carcinogenesis

    2018  Volume 39, Issue 7, Page(s) 851–859

    Abstract: Many chemical carcinogens require metabolic activation via xenobiotic-metabolizing enzymes in order to exert their genotoxic effects. Evidence from numerous in-vitro studies, utilizing reconstituted systems, microsomal fractions and cultured cells, ... ...

    Abstract Many chemical carcinogens require metabolic activation via xenobiotic-metabolizing enzymes in order to exert their genotoxic effects. Evidence from numerous in-vitro studies, utilizing reconstituted systems, microsomal fractions and cultured cells, implicates cytochrome P450 enzymes as being the predominant enzymes responsible for the metabolic activation of many procarcinogens. With the development of targeted gene disruption methodologies, knockout mouse models have been generated that allow investigation of the in-vivo roles of P450 enzymes in the metabolic activation of carcinogens. This review covers studies in which five procarcinogens representing different chemical classes, benzo[a]pyrene, 4-aminobiphenyl (4-ABP), 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine, 2-amino-9H-pyrido[2,3-b]indole and 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone, have been administered to different P450 knockout mouse models. Paradoxically, while in-vitro studies using subcellular fractions enriched with P450 enzymes and their cofactors have been widely used to determine the pathways of activation of carcinogens, there is evidence from the in-vivo studies of cases where these same enzyme systems appear to have a more predominant role in carcinogen detoxication rather than activation.
    MeSH term(s) Animals ; Benzo(a)pyrene/metabolism ; Butanones/metabolism ; Carcinogens/metabolism ; Cytochrome P-450 Enzyme System/metabolism ; Humans ; Inactivation, Metabolic/physiology ; Signal Transduction/physiology
    Chemical Substances Butanones ; Carcinogens ; Benzo(a)pyrene (3417WMA06D) ; Cytochrome P-450 Enzyme System (9035-51-2)
    Language English
    Publishing date 2018-05-05
    Publishing country England
    Document type Journal Article ; Research Support, Non-U.S. Gov't ; Review
    ZDB-ID 603134-1
    ISSN 1460-2180 ; 0143-3334
    ISSN (online) 1460-2180
    ISSN 0143-3334
    DOI 10.1093/carcin/bgy058
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