Mutagenesis最新文献

{"title":"Cobalt oxide (Co3O4) nanoparticles induced genotoxicity in Chinese hamster lung fibroblast (V79) cells through modulation of reactive oxygen species.","authors":"Onila Lugun, Jagreeti Singh, R. Thakur, A. Pandey","doi":"10.1093/mutage/geac005","DOIUrl":"https://doi.org/10.1093/mutage/geac005","url":null,"abstract":"Incessant production, pervasive applications in different fields, and eventually unintended exposure of cobalt oxide nanoparticles (Co3O4 NPs) lead to rise in their toxicity studies toward human health. However, the information regarding the potential toxicity mechanisms of Co3O4 NPs especially genotoxicity is still sparse with missing interconnections. So far, only solitary reports on Co3O4 NPs are at hand, bearing witness to reactive oxygen species (ROS)-mediated DNA damage in lung cells. To address this, we evaluated the Co3O4 NP-induced cytotoxic and genotoxic potential in Chinese hamster lung fibroblast cell line (V79). Our preliminary results demonstrate that Co3O4 NPs at concentrations of 20-100 µg/ml induced moderate mortality after 24-h exposure. However, these low concentrations caused a significant reduction in various organelles' activity in a concentration-dependent manner. Mitochondrial activity and membrane potential were found to be compromised due to NP exposure in a concentration-dependent manner. The study affirms that Co3O4 NPs inhibited lysosomal activity in V79 cells. In addition to this, Co3O4 NPs are also found to stimulate free oxygen radical generation. Genotoxicity studies revealed a potent and dose-dependent effect of non-cytotoxic concentrations of Co3O4 NPs in the induction of DNA lesions. Interestingly, N-acetylcysteine, a free oxygen radical scavenger (5, 10 mM, pretreatment) inhibited the progression of free oxygen radicals and induction of Co3O4 NP-mediated DNA lesions. This suggests the ROS-mediated genotoxic potential of Co3O4 NPs.","PeriodicalId":18889,"journal":{"name":"Mutagenesis","volume":"1 1","pages":""},"PeriodicalIF":2.7,"publicationDate":"2022-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"60857442","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Obituary for David G. Gatehouse (1951–2021)","authors":"","doi":"10.1093/mutage/geac002","DOIUrl":"https://doi.org/10.1093/mutage/geac002","url":null,"abstract":"<span></span>","PeriodicalId":18889,"journal":{"name":"Mutagenesis","volume":"67 1 1","pages":""},"PeriodicalIF":2.7,"publicationDate":"2022-02-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138518400","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Primary mesenchymal stromal cells in co-culture with leukaemic HL-60 cells are sensitised to cytarabine-induced genotoxicity, while leukaemic cells are protected.","authors":"Liana E Gynn,&nbsp;Elizabeth Anderson,&nbsp;Gareth Robinson,&nbsp;Sarah A Wexler,&nbsp;Gillian Upstill-Goddard,&nbsp;Christine Cox,&nbsp;Jennifer E May","doi":"10.1093/mutage/geab033","DOIUrl":"https://doi.org/10.1093/mutage/geab033","url":null,"abstract":"<p><p>Tumour microenvironments are hallmarked in many cancer types. In haematological malignancies, bone marrow (BM) mesenchymal stromal cells (MSC) protect malignant cells from drug-induced cytotoxicity. However, less is known about malignant impact on supportive stroma. Notably, it is unknown whether these interactions alter long-term genotoxic damage in either direction. The nucleoside analogue cytarabine (ara-C), common in haematological therapies, remains the most effective agent for acute myeloid leukaemia, yet one-third of patients develop resistance. This study aimed to evaluate the bidirectional effect of MSC and malignant cell co-culture on ara-C genotoxicity modulation. Primary MSC, isolated from patient BM aspirates for haematological investigations, and malignant haematopoietic cells (leukaemic HL-60) were co-cultured using trans-well inserts, prior to treatment with physiological dose ara-C. Co-culture genotoxic effects were assessed by micronucleus and alkaline comet assays. Patient BM cells from chemotherapy-treated patients had reduced ex vivo survival (P = 0.0049) and increased genotoxicity (P = 0.3172) than untreated patients. It was shown for the first time that HL-60 were protected by MSC from ara-C-induced genotoxicity, with reduced MN incidence in co-culture as compared to mono-culture (P = 0.0068). Comet tail intensity also significantly increased in ara-C-treated MSC with HL-60 influence (P = 0.0308). MSC sensitisation to ara-C genotoxicity was also demonstrated following co-culture with HL60 (P = 0.0116), which showed significantly greater sensitisation when MSC-HL-60 co-cultures were exposed to ara-C (P = 0.0409). This study shows for the first time that malignant HSC and MSC bidirectionally modulate genotoxicity, providing grounding for future research identifying mechanisms of altered genotoxicity in leukaemic microenvironments. MSC retain long-term genotoxic and functional damage following chemotherapy exposure. Understanding the interactions perpetuating such damage may inform modifications to reduce therapy-related complications, such as secondary malignancies and BM failure.</p>","PeriodicalId":18889,"journal":{"name":"Mutagenesis","volume":"36 6","pages":"419-428"},"PeriodicalIF":2.7,"publicationDate":"2021-11-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8633936/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"39403608","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"UCTD and SLE patients show increased levels of oxidative and DNA damage together with an altered kinetics of DSB repair.","authors":"Consuelo Micheli,&nbsp;Alice Parma,&nbsp;Chiara Tani,&nbsp;Domenica Di Bello,&nbsp;Aurora Falaschi,&nbsp;Anna Chiaramonte,&nbsp;Serena Testi,&nbsp;Marta Mosca,&nbsp;Roberto Scarpato","doi":"10.1093/mutage/geab036","DOIUrl":"https://doi.org/10.1093/mutage/geab036","url":null,"abstract":"Immunological tolerance is a critical feature of the immune system; its loss might lead to an abnormal response of lymphocytes causing autoimmune diseases. One of the most important groups belonging to autoimmune disorders is the connective tissue diseases (CTD). CTD are classified among systemic rheumatic diseases and include pathologies such as systemic lupus erythematosus (SLE), and undifferentiated CTD (UCTD). In this study, we evaluated oxidative and genome damage in peripheral blood lymphocytes from patients with SLE and UCTD, further classified on the basis of disease activity and the presence/absence of a serological profile. Oxidative damage was evaluated in cell membrane using the fluorescent fatty acid analogue BODIPY 581/591 C11. The percentage of oxidised lymphocytes in both SLE and UCTD patients was higher than in the control group, and the oxidative stress correlated positively with both disease activity and autoantibody profile. The γH2AX focus assay was used to quantify the presence of spontaneous double strand breaks (DSBs), and to assess the abilities of DSBs repair system after T cells were treated with mitomycin C (MMC). Subjects with these autoimmune disorders showed a higher number of γH2AX foci than healthy controls, but no correlation with diseases activity and presence of serological profile was observed. In addition, patients displayed an altered response to MMC-induced DSBs, which led their peripheral cells to greatly increase apoptosis. Taken together our results confirmed an interplay among oxidative stress, DNA damage and impaired DNA repair, which are directly correlated to the aggressiveness and clinical progression of the diseases. We propose the evaluation of these molecular markers to better characterize SLE and UCTD, aiming to improve the treatment plan and the quality of the patients' life.","PeriodicalId":18889,"journal":{"name":"Mutagenesis","volume":"36 6","pages":"429-436"},"PeriodicalIF":2.7,"publicationDate":"2021-11-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"39445586","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"In vitro and integrated in vivo strategies to reduce animal use in genotoxicity testing.","authors":"Katherine Groff,&nbsp;Stephen J Evans,&nbsp;Shareen H Doak,&nbsp;Stefan Pfuhler,&nbsp;Raffaella Corvi,&nbsp;Samantha Saunders,&nbsp;Gilly Stoddart","doi":"10.1093/mutage/geab035","DOIUrl":"https://doi.org/10.1093/mutage/geab035","url":null,"abstract":"<p><p>Scientific, financial, and ethical drivers have led to unprecedented interest in implementing human-relevant, mechanistic in vitro and in silico testing approaches. Further, as non-animal approaches are being developed and validated, researchers are interested in strategies that can immediately reduce the use of animals in toxicology testing. Here, we aim to outline a testing strategy for assessing genotoxicity beginning with standard in vitro methods, such as the bacterial reverse mutation test and the in vitro micronucleus test, followed by a second tier of in vitro assays including those using advanced 3D tissue models. Where regulatory agencies require in vivo testing, one demonstrated strategy is to combine genotoxicity studies traditionally conducted separately into a single test or to integrate genotoxicity studies into other toxicity studies. Standard setting organisations and regulatory agencies have encouraged such strategies, and examples of their use can be found in the scientific literature. Employing approaches outlined here will reduce animal use as well as study time and costs.</p>","PeriodicalId":18889,"journal":{"name":"Mutagenesis","volume":"36 6","pages":"389-400"},"PeriodicalIF":2.7,"publicationDate":"2021-11-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"39442062","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Genotoxicity of advanced glycation end products in vitro is influenced by their preparation temperature, purification and cell exposure time.","authors":"Emma L Jaunay,&nbsp;Varinderpal S Dhillon,&nbsp;Susan J Semple,&nbsp;Bradley S Simpson,&nbsp;Maulik Ghetia,&nbsp;Permal Deo,&nbsp;Michael Fenech","doi":"10.1093/mutage/geab037","DOIUrl":"https://doi.org/10.1093/mutage/geab037","url":null,"abstract":"<p><p>Advanced glycation end products (AGEs) are formed via non-enzymatic reactions between amino groups of proteins and the carbonyl groups of reducing sugars. Previous studies have shown that highly glycated albumin prepared using a glucose-bovine serum albumin (Glu-BSA) model system incubated at 60°C for 6 weeks induces genotoxicity in WIL2-NS cells at 9 days of exposure measured by the cytokinesis-block micronucleus cytome (CBMNcyt) assay. However, this AGE model system is not physiologically relevant as normal body temperature is 37°C and the degree of glycation may exceed the extent of albumin modification in vivo. We hypothesised that the incubation temperature and purification method used in these studies may cause changes to the chemical profile of the glycated albumin and may influence the extent of genotoxicity observed at 3, 6 and 9 days of exposure. We prepared AGEs generated using Glu-BSA model systems incubated at 60°C or 37°C purified using trichloroacetic acid (TCA) precipitation or ultrafiltration (UF) and compared their chemical profile (glycation, oxidation, and aggregation) and genotoxicity in WIL2-NS cells using the CBMNcyt assay after 3, 6 and 9 days of exposure. The number of micronuclei (MNi) was significantly higher for cells treated with Glu-BSA incubated at 60°C and purified via TCA (12 ± 1 MNi/1000 binucleated cells) compared to Glu-BSA incubated at 37°C and purified using UF (6 ± 1 MNi/1000 binucleated cells) after 9 days (P < 0.0001). The increase in genotoxicity observed could be explained by a higher level of protein glycation, oxidation, and aggregation of the Glu-BSA model system incubated at 60°C relative to 37°C. This study highlighted that the incubation temperature, purification method and cell exposure time are important variables to consider when generating AGEs in vitro and will enable future studies to better reflect in vivo situations of albumin glycation.</p>","PeriodicalId":18889,"journal":{"name":"Mutagenesis","volume":"36 6","pages":"445-455"},"PeriodicalIF":2.7,"publicationDate":"2021-11-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"39491125","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Biomarkers of DNA damage response improve in vitro micronucleus assays by revealing genotoxic mode of action and reducing the occurrence of irrelevant positive results.","authors":"Svetlana Avlasevich,&nbsp;Tina Pellegrin,&nbsp;Manali Godse,&nbsp;Steven Bryce,&nbsp;Jeffrey Bemis,&nbsp;Peter Bajorski,&nbsp;Stephen Dertinger","doi":"10.1093/mutage/geab039","DOIUrl":"https://doi.org/10.1093/mutage/geab039","url":null,"abstract":"<p><p>We have previously described two flow cytometry-based in vitro genotoxicity tests: micronucleus (MN) scoring (MicroFlow®) and a multiplexed DNA damage response biomarker assay (MultiFlow®). Here, we describe a strategy for combining the assays in order to efficiently supplement MN analyses with a panel of biomarkers that comment on cytotoxicity (i.e. relative nuclei count, relative increased nuclei count, cleaved PARP-positive chromatin and ethidium monoazide-positive chromatin) and genotoxic mode of action (MoA; i.e. γH2AX, phospho-histone H3, p53 activation and polyploidy). For these experiments, human TK6 cells were exposed to each of 32 well-studied reference chemicals in 96-well plates for 24 continuous hours. The test chemicals were evaluated over a range of concentrations in the presence and absence of a rat liver S9-based metabolic activation system. MultiFlow assay data were acquired at 4 and 24 h, and micronuclei were scored at 24 h. Testing 32 chemicals in two metabolic activation arms translated into 64 a priori calls: 42 genotoxicants and 22 non-genotoxicants. The MN assay showed high sensitivity and moderate specificity (90% and 68%, respectively). When a genotoxic call required significant MN and MultiFlow responses, specificity increased to 95% without adversely affecting sensitivity. The dose-response data were analysed with PROAST Benchmark Dose (BMD) software in order to calculate potency metrics for each endpoint, and ToxPi software was used to synthesise the resulting lower and upper bound 90% confidence intervals into visual profiles. The BMD/ToxPi combination was found to represent a powerful strategy for synthesising multiple BMD confidence intervals, as the software output provided MoA information as well as insights into genotoxic potency.</p>","PeriodicalId":18889,"journal":{"name":"Mutagenesis","volume":"36 6","pages":"407-418"},"PeriodicalIF":2.7,"publicationDate":"2021-11-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8633886/pdf/geab039.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"39577106","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Evaluation of the liver and blood micronucleus, and comet assay end points in a 14-day repeated-dose study with methyl carbamate and 1,3-propane sultone.","authors":"Honggang Tu,&nbsp;Chunrong Yu,&nbsp;Wen Tong,&nbsp;Changhui Zhou,&nbsp;Ruowan Li,&nbsp;Pengcheng Huang,&nbsp;Qingli Wang,&nbsp;Yan Chang","doi":"10.1093/mutage/geab034","DOIUrl":"https://doi.org/10.1093/mutage/geab034","url":null,"abstract":"<p><p>The repeated-dose liver micronucleus (RDLMN) assay is a novel method for detecting genotoxic chemicals. Two carcinogens methyl carbamate (MC) and 1,3-propane sultone (PS) were evaluated for the liver micronucleus in a 14-day repeated-dose study with Crl: CD (SD) IGS rats. Additionally, micronucleated reticulocytes (MN-RET) in peripheral blood and DNA damage (alkaline comet assay) in the liver were also assessed in the same animals. Ten groups of five male Crl: CD (SD) IGS rats were treated once daily with MC (300, 600 or 1200 mg/kg/day), PS (37.5, 75 or 150 mg/kg/day), negative control or three positive controls by oral gavage for 15 days. Blood samples were collected at 3 h after the last administration for determining MN-RET frequencies (%MN-RET), and the livers were sampled for determining the frequency of micronuclei and DNA damage. MC was negative in the comet assay, liver micronucleus assay and reticulocyte micronucleus assay, while PS was positive in all three assays. These results are consistent with the previous genotoxic findings of MC and PS. Therefore, the liver micronucleus assay can be effectively integrated into repeated-dose studies in animals. Moreover, integration of multiple genotoxicity end points into one study can reduce the number of animals, boost the experimental efficiency, and provides a comprehensive evaluation of the genotoxic potential of chemicals.</p>","PeriodicalId":18889,"journal":{"name":"Mutagenesis","volume":"36 6","pages":"401-406"},"PeriodicalIF":2.7,"publicationDate":"2021-11-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"39412116","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Upregulation of mNEIL3 in Ogg1-null cells is a potential backup mechanism for 8-oxoG repair.","authors":"Ellen B Higgs,&nbsp;Roger Godschalk,&nbsp;Sabine A S Langie,&nbsp;Frederik-Jan van Schooten,&nbsp;Nikolas J Hodges","doi":"10.1093/mutage/geab038","DOIUrl":"https://doi.org/10.1093/mutage/geab038","url":null,"abstract":"<p><p>Reactive oxygen species formation and resultant oxidative damage to DNA are ubiquitous events in cells, the homeostasis of which can be dysregulated in a range of pathological conditions. Base excision repair (BER) is the primary repair mechanism for oxidative genomic DNA damage. One prevalent oxidised base modification, 8-oxoguanine (8-oxoG), is recognised by 8-oxoguanine glycosylase-1 (OGG1) initiating removal and repair via BER. Surprisingly, Ogg1 null mouse embryonic fibroblasts (mOgg1-/- MEFs) do not accumulate 8-oxoG in the genome to the extent expected. This suggests that there are backup repair mechanisms capable of repairing 8-oxoG in the absence of OGG1. In the current study, we identified components of NER (Ercc1, Ercc4, Ercc5), BER (Lig1, Tdg, Nthl1, Mpg, Mgmt, NEIL3), MMR (Mlh1, Msh2, Msh6) and DSB (Brip1, Rad51d, Prkdc) pathways that are transcriptionally elevated in mOgg1-/- MEFs. Interestingly, all three nucleotide excision repair genes identified: Ercc1 (2.5 ± 0.2-fold), Ercc4 (1.5 ± 0.1-fold) and Ercc5 (1.7 ± 0.2-fold) have incision activity. There was also a significant functional increase in NER activity (42.0 ± 7.9%) compared to WT MEFs. We also observed upregulation of both Neil3 mRNA (37.9 ± 1.6-fold) and protein in mOgg1-/- MEFs. This was associated with a 3.4 ± 0.4-fold increase in NEIL3 substrate sites in genomic DNA of cells treated with BSO, consistent with the ability of NEIL3 to remove 8-oxoG oxidation products from genomic DNA. In conclusion, we suggest that in Ogg1-null cells, upregulation of multiple DNA repair proteins including incision components of the NER pathway and Neil3 are important compensatory responses to prevent the accumulation of genomic 8-oxoG.</p>","PeriodicalId":18889,"journal":{"name":"Mutagenesis","volume":"36 6","pages":"437-444"},"PeriodicalIF":2.7,"publicationDate":"2021-11-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"39514086","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Erratum to: The effect of chronic dosing and p53 status on the genotoxicity of pro-oxidant chemicals in vitro.","authors":"Emrah Dural, Ume-Kulsoom Shah, Demi Pritchard, Katherine Emma Chapman, Shareen Heather Doak, Gareth James Scott Jenkins","doi":"10.1093/mutage/geab029","DOIUrl":"10.1093/mutage/geab029","url":null,"abstract":"","PeriodicalId":18889,"journal":{"name":"Mutagenesis","volume":"36 5","pages":"388"},"PeriodicalIF":2.7,"publicationDate":"2021-10-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"9474768","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}