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1.
Talanta ; 235: 122809, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34517666

RESUMO

The 8-oxoguanine (8-oxoG) represents the most common DNA damage type, and it has been regarded as the oxidative stress biomarker, but the reported 8-oxoguanine assays are limited by poor specificity and low sensitivity. Herein, we demonstrate the construction of damage site-specific fluorescent biosensor for 8-oxoG assay by integrating single-molecule detection with hyperbranched signal amplification. In this assay, the 8-oxoG damages in DNA can generate free 3' OH with the assistance of formamidopyrimidine DNA glycosylase (Fpg) and polynucleotide kinase (PNK), which subsequently triggers the incorporation of abundant Cy5-labeled dUTPs via terminal deoxynucleotidyl transferase (TDT)-mediated site-specific hyperbranched nucleic acid amplification. After digestion of amplification products with nuclease treatment, abundant mononucleotide Cy5-dUTPs are produced, which will be easily monitored via single-molecule imaging and detection. The introduction of hyperbranched nucleic acid amplification and single-molecule detection can greatly improve the sensitivity to achieve a detection limit of 7.62 × 10-18 M. This biosensor is highly specific with the capability of discriminating 0.001% 8-oxoG target from the DNA mixture. Moreover, it can be applied for quantitative detection of 8-oxoG damage in genomic DNAs with a detection limit of 0.0017 ng, and even accurately quantifies the absolute number (7025 - 8506) of 8-oxoG damage base in single HeLa cell treated with 150 µM H2O2. Importantly, this biosensor can measure the 8-oxoG damage level in different cancer cell lines, facilitating the oxidative damage-associated biomedical researches and clinical diagnosis.


Assuntos
Técnicas Biossensoriais , Peróxido de Hidrogênio , Dano ao DNA , DNA-Formamidopirimidina Glicosilase , Feminino , Células HeLa , Humanos
2.
Nat Commun ; 12(1): 5217, 2021 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-34471116

RESUMO

Lethal hit delivery by cytotoxic T lymphocytes (CTL) towards B lymphoma cells occurs as a binary, "yes/no" process. In non-hematologic solid tumors, however, CTL often fail to kill target cells during 1:1 conjugation. Here we describe a mechanism of "additive cytotoxicity" by which time-dependent integration of sublethal damage events, delivered by multiple CTL transiting between individual tumor cells, mediates effective elimination. Reversible sublethal damage includes perforin-dependent membrane pore formation, nuclear envelope rupture and DNA damage. Statistical modeling reveals that 3 serial hits delivered with decay intervals below 50 min discriminate between tumor cell death or survival after recovery. In live melanoma lesions in vivo, sublethal multi-hit delivery is most effective in interstitial tissue where high CTL densities and swarming support frequent serial CTL-tumor cell encounters. This identifies CTL-mediated cytotoxicity by multi-hit delivery as an incremental and tunable process, whereby accelerating damage magnitude and frequency may improve immune efficacy.


Assuntos
Citotoxicidade Imunológica , Melanoma/terapia , Perforina/metabolismo , Linfócitos T Citotóxicos/imunologia , Animais , Apoptose/imunologia , Morte Celular , Linhagem Celular Tumoral , Dano ao DNA , Feminino , Humanos , Cinética , Células MCF-7 , Masculino , Camundongos Endogâmicos C57BL , Perforina/genética
3.
Nat Commun ; 12(1): 5205, 2021 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-34471128

RESUMO

Molecular mechanisms associated with human germ cell aplasia in infertile men remain undefined. Here we perform single-cell transcriptome profiling to highlight differentially expressed genes and pathways in each somatic cell type in testes of men with idiopathic germ cell aplasia. We identify immaturity of Leydig cells, chronic tissue inflammation, fibrosis, and senescence phenotype of the somatic cells, as well markers of chronic inflammation in the blood. We find that deregulated expression of parentally imprinted genes in myoid and immature Leydig cells, with relevant changes in the ratio of Lamin A/C transcripts and an active DNA damage response in Leydig and peritubular myoid cells are also indicative of senescence of the testicular niche. This study offers molecular insights into the pathogenesis of idiopathic germ cell aplasia.


Assuntos
Envelhecimento/fisiologia , Dano ao DNA , Inflamação , Testículo/metabolismo , Envelhecimento/genética , Comunicação Celular , Quimiocinas , Perfilação da Expressão Gênica , Células Germinativas , Humanos , Inflamação/patologia , Células Intersticiais do Testículo , Masculino , Fenótipo , Alinhamento de Sequência , Espermatogênese/genética , Espermatogênese/fisiologia , Espermatogônias/metabolismo , Transcriptoma
4.
J Hazard Mater ; 416: 125903, 2021 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-34492839

RESUMO

Copper is considered as an indispensable trace element for living organisms. However, over-exposure to Cu can lead to adverse health effects on human. In this study, CuSO4 decreased sperm concentration and motility, increased sperm malformation rate. Concurrently, testicular damage including testicular histopathological aberrations and reduction of testis relative weight were observed. Then, the mechanism underlying Cu-induced testicular toxicity was explored. According to the results, CuSO4 elevated ROS production while reducing antioxidant function. Additionally, CuSO4 induced apoptosis which was featured by MMP depolarization and up-regulated levels of cleaved-caspase-3, cleaved-caspase-8, cleaved-caspase-9, caspase-12, cleaved-PARP and Bax, whereas down-regulated Bcl-2 expression. Meanwhile, CuSO4 caused testis DNA damage (up-regulation of γ-H2AX protein expression) and suppressed DNA repair pathways including BER, NER, HR, MMR, together with the NHEJ repair pathways, yet did not affect MGMT. To investigate the role of oxidative stress in CuSO4-induced apoptosis and DNA damage, the antioxidant NAC was co-treated with CuSO4. NAC attenuated CuSO4-induced ROS production, inhibited apoptosis and DNA damage. Furthermore, the spermatogenesis disorder was also abolished in the co-treatment with CuSO4 and NAC group. Altogether, abovementioned results indicated that CuSO4-induced spermatogenesis disorder is related to oxidative stress-mediated DNA damage and germ cell apoptosis, impairing male reproductive function.


Assuntos
Estresse Oxidativo , Espermatogênese , Apoptose , Dano ao DNA , Humanos , Masculino , Espermatozoides , Testículo/metabolismo
5.
J Hazard Mater ; 416: 126053, 2021 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-34492893

RESUMO

Various genotoxic substances in household effluents have not been sufficiently studied. The purpose of this study is to evaluate them using the umu test after dividing them based on the acid-base properties of their functional groups by solid-phase extraction cartridges. The results of the samples concentrated with reverse-phase cartridges showed that the substances with acid functional groups had stronger genotoxicity as 4.1-12.1 ng-4-NQO/mL without S9 enzyme and 17.4-51.8 ng-2-AA/mL with S9 enzyme, while the basic substances also showed a certain degree of toxicity. The results of dividing the effluents by acid-base properties using ion-exchange cartridges showed that chemical substances with strong acid functional groups did not demonstrate genotoxicity. It was found that the genotoxicity of chemicals with functional groups of weak acids was half of that of the total amount. The genotoxicity of the neutral substance was not strong, and the genotoxicity of the weak basic substances was negligible. The zwitterions and substances with strong basic functional groups showed about half the total genotoxicity. This is the first report that has investigated the genotoxicity of zwitterions in effluents.


Assuntos
Poluentes Químicos da Água , Dano ao DNA , Testes de Mutagenicidade , Mutagênicos/toxicidade , Extração em Fase Sólida , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade
6.
Nanoscale ; 13(34): 14525-14537, 2021 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-34473816

RESUMO

Radiotherapy (RT) is one of the main treatments for men with prostate cancer (PCa). To date, numerous sophisticated nano-formulations as radiosensitizers have been synthesized with inspiring therapeutic effects both in vitro and in vivo; however, almost all the attention has been paid on the enhanced dose deposition effect by secondary electrons of nanomaterials with high atomic numbers (Z); despite this, cell-cycle arrest, DNA damage, and also reactive oxygen species (ROS) production are critical working mechanisms that account for radiosensitization. Herein, an 'all-purpose' nanostrategy based on dose deposition enhancement, cell cycle arrest, and ROS production as prostate cancer radiosensitizer for potential clinical translation was proposed. The rather simple structure of docetaxel-loaded Au nanoparticles (NPs) with prostate specific membrane antigen (PSMA) ligand conjugation have been successfully synthesized. Enhanced cellular uptake achieved via the selective internalization of the NPs by PCa cells with positive PSMA expression could guarantee enhanced dose deposition. Moreover, the as-synthesized nanosystem could effectively arrest the cell cycle at G2/M phases, which would reduce the ability of DNA damage repair for more irradiation sensitive of the PCa cells. Moreover, the G2/M phase arrest would further promote cascade retention and the enrichment of NPs within the cells. Furthermore, ROS generation and double strand breaks greatly promoted by NPs under irradiation (IR) could also provide an underlying basis for effective radiosensitizers. In vitro and in vivo investigations confirmed the as-synthesized NPs as an effective nano-radiosensitizer with ideal safety. More importantly, all moieties within the present nanosystem have been approved by FDA for the purpose of PCa treatment, thus making it highly attractive for clinical translation.


Assuntos
Nanopartículas Metálicas , Neoplasias da Próstata , Pontos de Checagem do Ciclo Celular , Dano ao DNA , Ouro , Humanos , Masculino , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/genética , Neoplasias da Próstata/radioterapia , Espécies Reativas de Oxigênio
7.
Braz J Biol ; 83: e248022, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34468531

RESUMO

Previous studies have suggested that arsenic crosses the placenta and affects the fetus development. The study under consideration aims to show comparative ameliorative effect of Moringa oleifera leaf and flower extracts against sodium arsenate induced fetus toxicity of mice. Pregnant mice (N=44) were kept in lab and divided into eleven group from (A to K) and were orally administered the doses 6 mg/kg, 12 mg/kg for sodium arsenate, 150 mg/kg and 300 mg/kg for Moringa oleifera leaf extracts (MOLE) and 150 mg/kg and 300 mg/kg for Moringa oleifera flower extracts (MOFE) comparing with control. The investigation revealed evident reduction in the fetuses weight, hind limb, fore limb, tail and snout length, crown rump and head circumferences well as malformations in tail, feet, arms, legs, skin and eyes in the negative control group (only administered with sodium arsenate). Co-administration of sodium arsenate with MOLE and MOFE ameliorate the reversed effect of sodium arsenate on the shape, length, body weight and DNA damage of fetus significantly at 95% confidence interval. However, Moringa oleifera leaf extract showed more significant results in comparison to Moringa oleifera flower extract. Hence concluded that Moringa oleifera leaf extract ameliorated the embryo toxic effects of sodium arsenate and can be used against environmental teratogens.


Assuntos
Moringa oleifera , Animais , Arseniatos , Dano ao DNA , Camundongos , Extratos Vegetais/farmacologia , Folhas de Planta
8.
Georgian Med News ; (316-317): 154-158, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34511463

RESUMO

Malignant tumors are one of the leading courses of mortality in the world, and it is believed that 19% of malignant tumors are associated with environmental risk factors. The aim of the study was to establish the spectrum of distributions of an informative biomarker of the unfavorable (genotoxic) effect of the external environment on the body by determining the level of micronuclei (LMN) in buccal epithelium cells in populations of villages of the Sachkhera region (Georgia). In the inhabitants of the Sachkhere district (both sexes, 50-65 years old) living in the villages of Sareki, Sairkhe, and Chorvila, LMN was determined in the cells of the buccal epithelium. The statistical significance of the difference in LML between the village population was assessed using the analysis of variance (ANOVA). Dixon's Q test was used to identify abnormal micronuclei. The χ2 criterion was used to assess the normality of LMN distributions among residents of the villages. The distribution of the population by LMN indicators in each individual village was described as the distribution of a two-component mixture. The statistical significance of the difference between the Gaussian means of the mixture components was assessed using the Z-test. To analyze the data and visualize the results, the SPSS and Open BUGS software packages were used. Differences in the LMN of the buccal epithelium in the studied populations were revealed, which may be due to the influence of external environmental factors: in Sareki, the effect of a certain (unidentified) clearly expressed genotoxic factor (both in terms of intensity and scale of exposure) was revealed, which is accompanied by a sharp increase in LMN, while in Chorvila and Sairkhe the presence of an inducing factor is not recorded and LMN remained practically within the norms. The identification of the causal relationship between the nature of the distributions of the used biomarkers and the specificity of the incidence of the population in the villages, as well as the possible contribution of unfavorable environmental factors, is the subject of further research.


Assuntos
Dano ao DNA , Mucosa Bucal , Idoso , Teorema de Bayes , Biomarcadores , Feminino , República da Geórgia , Humanos , Masculino , Pessoa de Meia-Idade
9.
Anticancer Res ; 41(9): 4203-4210, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34475039

RESUMO

AIM: The aim of this review was to evaluate the scientific literature regarding the cytogenetic damage in oral exfoliated cells of adult patients submitted to panoramic X-ray. MATERIALS AND METHODS: An extensive search of the literature was conducted on PubMed, Scopus and Web of Science databases for all studies published until April 2021 using combinations of the following keywords: "panoramic X-ray," "DNA damage," "genetic damage", "genotoxicity", "mutagenicity", cytotoxicity", "buccal cells", "oral mucosa", "tongue", "gingiva", "micronucleus assay", according to the PRISMA guidelines. All clinical studies in English language were included in the study. A total of 10 studies were identified. RESULTS: As expected, the results regarding the cytogenetic damage induced by panoramic X-ray are conflicting. Some authors have demonstrated that panoramic X-ray induces mutagenesis in oral cells, whereas others did not. After reviewing the 10 studies, two were classified as strong, four were considered moderate, and four were considered weak, according to the quality assessment components of the Effective Public Health Practice Project (EPHPP). Meta-analysis data revealed a negative response related to mutagenicity in oral cells by panoramic X-ray. CONCLUSION: Taken together, this review failed to demonstrate the association between micronucleus frequency and panoramic X-ray.


Assuntos
Análise Citogenética/métodos , Mucosa Bucal/química , Radiografia Panorâmica/efeitos adversos , Dano ao DNA , Humanos , Testes para Micronúcleos , Mucosa Bucal/efeitos dos fármacos , Mutação
10.
Anticancer Res ; 41(9): 4343-4351, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34475054

RESUMO

BACKGROUND/AIM: Ally lisothiocyanate (AITC), a constituent of naturally occurring isothiocyanates (ITCs) found in some Brassica vegetables, has been previously demonstrated to have anti-carcinogenic activity. However, there is no available information showing that AITC induces DNA damage and alters DNA damage repair proteins in human breast cancer MCF-7 cells. MATERIALS AND METHODS: In the present study, we investigated the effects of AITC on DNA damage and repair responses in human breast cancer MCF-7 cells in vitro. Cell viability was measured by flow cytometric assay. DNA condensation (apoptotic cell death) and DNA fragmentation (laddered DNA) were assayed by DAPI staining and DNA gel electrophoresis assays, respectively. Furthermore, DNA damage (comet tail) was measured by the comet assay. Western blotting was used to measure the expression of DNA damage- and repair-associated proteins. RESULTS: AITC decreased cell viability in a dose-dependent and induced apoptotic cell death (DNA condensation and fragmentation) and DNA damage in MCF-7 cells. AITC increased p-ATMSer1981, p-ATRSer428, p53, p-p53Ser15, p-H2A.XSer139, BRCA1, and PARP at 10-30 µM at 24 and 48 h treatments. However, AITC decreased DNA-PK at 24 and 48 h treatment, and decreased MGMT at 48 h in MCF-7 cells. CONCLUSION: AITC induced cytotoxic effects (decreased viable cell number) through induction of DNA damage and condensation and altered DNA damage and repair associated proteins in MCF-7 cells in vitro.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Neoplasias da Mama/genética , Reparo do DNA/efeitos dos fármacos , Isotiocianatos/farmacologia , Neoplasias da Mama/metabolismo , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Dano ao DNA , Relação Dose-Resposta a Droga , Feminino , Redes Reguladoras de Genes/efeitos dos fármacos , Humanos , Células MCF-7
11.
BMC Genomics ; 22(1): 669, 2021 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-34535077

RESUMO

BACKGROUND: DNA damage repair (DDR) system is vital in maintaining genome stability and survival. DDR consists of over 160 genes in 7 different pathways to repair specific type of DNA damage caused by external and internal damaging factors. The functional importance of DDR system implies that evolution could play important roles in maintaining its functional intactness to perform its function. Indeed, it has been observed that positive selection is present in BRCA1 and BRCA2 (BRCA), which are key genes in homologous recombination pathway of DDR system, in the humans and its close relatives of chimpanzee and bonobos. Efforts have been made to investigate whether the same selection could exist for BRCA in other mammals but found no evidence so far. However, as most of the studies in non-human mammals analyzed only a single or few individuals in the studied species, the observation may not reflect the true status in the given species. Furthermore, few studies have studied evolution selection in other DDR genes except BRCA. In current study, we used laboratory mouse C57BL/6 J as a model to address evolution selection on DDR genes in non-primate mammals by dynamically monitoring genetic variation across 30 generations in C57BL/6 J. RESULTS: Using exome sequencing, we collected coding sequences of 169 DDR genes from 44 C57BL/6 J individual genomes in 2018. We compared the coding sequences with the mouse reference genome sequences derived from 1998 C57BL/6 J DNA, and with the mouse Eve6B reference genome sequences derived from 2003 C57BL/6 J DNA, covering 30 generations of C57BL/6 J from 1998 to 2018. We didn't identify meaningful coding variation in either Brca1 or Brca2, or in 167 other DDR genes across the 30 generations. In the meantime, we did identify 812 coding variants in 116 non-DNA damage repair genes during the same period, which served as a quality control to validate the reliability of our analytic pipeline and the negative results in DDR genes. CONCLUSIONS: DDR genes in laboratory mouse strain C57BL/6 J were not under positive selection across its 30-generation period, highlighting the possibility that DDR system in rodents could be evolutionarily stable.


Assuntos
Dano ao DNA , Reparo do DNA , Animais , Dano ao DNA/genética , Reparo do DNA/genética , Instabilidade Genômica , Camundongos , Camundongos Endogâmicos C57BL , Reprodutibilidade dos Testes
12.
Curr Protoc ; 1(8): e216, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34399037

RESUMO

Exposure of bone marrow to genotoxic stress such as ionizing radiation (IR) results in a rapid decline of peripheral blood cells and stimulates entry of the normally quiescent hematopoietic stem cells (HSCs) into the cell cycle to reconstitute the hematopoietic system. While several protocols have employed flow cytometry analysis of bone marrow cells to study changes in specific cell populations with respect to cell cycle proliferation and/or expression of γ-H2AX, a marker of DNA damage, these parameters were examined in separate panels. Here, we describe a flow cytometry-based method specifically designed to examine cell cycle distribution using Ki-67 and FXCycle violet in combination with γ-H2AX in HSCs and hematopoietic progenitor cells (HPCs) within the same sample. This method is very useful, particularly in studies involving genotoxic stresses such as IR, which substantially reduce the absolute numbers of HSCs and HPCs available for staining. Additionally, we describe several important considerations for the analysis of markers of HSCs in irradiated versus unirradiated samples. Examples include the use of fluorescence minus one (FMO) controls, the gating strategy for markers whose expression is typically impacted by IR such as Sca1, tips for staining of intracellular antigens like Ki67, and ensuring the detection of signal from at least 500 events in each gate to ensure robustness of the results. © 2021 Wiley Periodicals LLC. Basic Protocol: Immunostaining protocol for bone marrow mononuclear cells using a multi-fluorophore panel.


Assuntos
Dano ao DNA , Células-Tronco Hematopoéticas , Animais , Medula Óssea , Ciclo Celular , Citometria de Fluxo , Humanos , Camundongos
13.
J Enzyme Inhib Med Chem ; 36(1): 1916-1921, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34461785

RESUMO

An earlier described three-component variant of the Castagnoli-Cushman reaction employing homophthalic anhydrides, carbonyl compound and ammonium acetate was applied towards the preparation of 1-oxo-3,4-dihydroisoquinoline-4-carboxamides with variable substituent in position 3. These compounds displayed inhibitory activity towards poly(ADP-ribose) polymerase (PARP), a clinically validated cancer target. The most potent compound (PARP1/2 IC50 = 22/4.0 nM) displayed the highest selectivity towards PARP2 in the series (selectivity index = 5.5), more advantageous ADME prameters compared to the clinically used PARP inhibitor Olaparib.


Assuntos
Acetatos/química , Antineoplásicos/química , Inibidores de Poli(ADP-Ribose) Polimerases/química , Poli(ADP-Ribose) Polimerases/metabolismo , Quinolonas/química , Acetatos/farmacologia , Sequência de Aminoácidos , Antineoplásicos/farmacologia , Sítios de Ligação , Dano ao DNA/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , NAD/metabolismo , Ftalazinas/farmacologia , Piperazinas/farmacologia , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia , Ligação Proteica , Conformação Proteica , Relação Estrutura-Atividade
14.
BMC Genomics ; 22(1): 600, 2021 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-34362292

RESUMO

BACKGROUND: Nucleotide excision repair is the primary DNA repair mechanism that removes bulky DNA adducts such as UV-induced pyrimidine dimers. Correspondingly, genome-wide mapping of nucleotide excision repair with eXcision Repair sequencing (XR-seq), provides comprehensive profiling of DNA damage repair. A number of XR-seq experiments at a variety of conditions for different damage types revealed heterogenous repair in the human genome. Although human repair profiles were extensively studied, how repair maps vary between primates is yet to be investigated. Here, we characterized the genome-wide UV-induced damage repair in gray mouse lemur, Microcebus murinus, in comparison to human. RESULTS: We derived fibroblast cell lines from mouse lemur, exposed them to UV irradiation, and analyzed the repair events genome-wide using the XR-seq protocol. Mouse lemur repair profiles were analyzed in comparison to the equivalent human fibroblast datasets. We found that overall UV sensitivity, repair efficiency, and transcription-coupled repair levels differ between the two primates. Despite this, comparative analysis of human and mouse lemur fibroblasts revealed that genome-wide repair profiles of the homologous regions are highly correlated, and this correlation is stronger for highly expressed genes. With the inclusion of an additional XR-seq sample derived from another human cell line in the analysis, we found that fibroblasts of the two primates repair UV-induced DNA lesions in a more similar pattern than two distinct human cell lines do. CONCLUSION: Our results suggest that mouse lemurs and humans, and possibly primates in general, share a homologous repair mechanism as well as genomic variance distribution, albeit with their variable repair efficiency. This result also emphasizes the deep homologies of individual tissue types across the eukaryotic phylogeny.


Assuntos
Dano ao DNA , Dímeros de Pirimidina , Animais , Dano ao DNA/genética , Reparo do DNA/genética , Genoma Humano , Humanos , Primatas/genética , Raios Ultravioleta
15.
Front Public Health ; 9: 701878, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34368064

RESUMO

The effect of the reportedly low ionizing radiation doses, such as those very often delivered to patients in interventional cardiology, remains ambiguous. As interventional cardiac procedures may have a significant impact on total collective effective dose, there are radiation protection concerns for patients and physicians regarding potential late health effects. Given that very low doses (<100 mSv) are expected to be delivered during these procedures, the purpose of this study was to assess the potency and suitability of current genotoxicity biomarkers to detect and quantitate biological effects essential for risk estimation in interventional cardiology. Specifically, the biomarkers γ-H2AX foci, dicentric chromosomes, and micronuclei, which underpin radiation-induced DNA damage, were studied in blood lymphocytes of 25 adult patients before and after interventional cardiac procedures. Even though the mean values of all patients as a group for all three endpoints tested show increased yields relative to baseline following medical exposure, our results demonstrate that only the γ-H2AX biomarker enables detection of statistically significant differences at the individual level (p < 0.001) for almost all patients (91%). Furthermore, 24 h after exposure, residual γ-H2AX foci were still detectable in irradiated lymphocytes. Their decline was found to vary significantly among the individuals and the repair kinetics of γ-H2AX foci was found to range from 25 to 95.6% of their maximum values obtained.


Assuntos
Cardiologia , Lesões por Radiação , Adulto , Biomarcadores , Dano ao DNA , Relação Dose-Resposta à Radiação , Histonas/genética , Humanos
16.
Nature ; 596(7870): 43-53, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34349292

RESUMO

The genomes of virtually all organisms contain repetitive sequences that are generated by the activity of transposable elements (transposons). Transposons are mobile genetic elements that can move from one genomic location to another; in this process, they amplify and increase their presence in genomes, sometimes to very high copy numbers. In this Review we discuss new evidence and ideas that the activity of retrotransposons, a major subgroup of transposons overall, influences and even promotes the process of ageing and age-related diseases in complex metazoan organisms, including humans. Retrotransposons have been coevolving with their host genomes since the dawn of life. This relationship has been largely competitive, and transposons have earned epithets such as 'junk DNA' and 'molecular parasites'. Much of our knowledge of the evolution of retrotransposons reflects their activity in the germline and is evident from genome sequence data. Recent research has provided a wealth of information on the activity of retrotransposons in somatic tissues during an individual lifespan, the molecular mechanisms that underlie this activity, and the manner in which these processes intersect with our own physiology, health and well-being.


Assuntos
Envelhecimento/genética , Envelhecimento/patologia , Doença/genética , Retroelementos/genética , Animais , Dano ao DNA , Inativação Gênica , Genoma Humano/genética , Genômica , Humanos , Imunidade Inata
17.
Nat Commun ; 12(1): 4750, 2021 08 06.
Artigo em Inglês | MEDLINE | ID: mdl-34362907

RESUMO

Budding yeast Dpb4 (POLE3/CHRAC17 in mammals) is a highly conserved histone fold protein that is shared by two protein complexes: the chromatin remodeler ISW2/hCHRAC and the DNA polymerase ε (Pol ε) holoenzyme. In Saccharomyces cerevisiae, Dpb4 forms histone-like dimers with Dls1 in the ISW2 complex and with Dpb3 in the Pol ε complex. Here, we show that Dpb4 plays two functions in sensing and processing DNA double-strand breaks (DSBs). Dpb4 promotes histone removal and DSB resection by interacting with Dls1 to facilitate the association of the Isw2 ATPase to DSBs. Furthermore, it promotes checkpoint activation by interacting with Dpb3 to facilitate the association of the checkpoint protein Rad9 to DSBs. Persistence of both Isw2 and Rad9 at DSBs is enhanced by the A62S mutation that is located in the Dpb4 histone fold domain and increases Dpb4 association at DSBs. Thus, Dpb4 exerts two distinct functions at DSBs depending on its interactors.


Assuntos
Quebras de DNA de Cadeia Dupla , DNA Polimerase II/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/metabolismo , Adenosina Trifosfatases/metabolismo , Montagem e Desmontagem da Cromatina , DNA/metabolismo , Dano ao DNA , Reparo do DNA , Histonas/metabolismo , Mutação , Fatores de Transcrição
18.
Ecotoxicol Environ Saf ; 223: 112598, 2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-34388657

RESUMO

Oocyte quality is critical for fertilization and early embryo development. Fumonisin B1 (FB1) is a Fusarium mycotoxin and it is commonly found in contaminated food and feedstuff, posing a potential health hazard to both animals and human. FB1 is reported to have hepatotoxicity, neurotoxicity, nephrotoxicity, immunotoxicity and embryotoxicity. However, the effects of FB1 on mouse oocyte quality are still unknown. Here, we explored the toxic effects and potential mechanisms of FB1 on oocyte maturation quality in mice. FB1 exposure inhibited the first polar body extrusion at concentrations of 30 µM and 50 µM, which further induced oocyte meiotic arrest. Besides, disrupted spindle structure was found in oocytes after FB1 exposure. Our results also showed that FB1 exposure impaired mitochondria dysfunction, which further induced oxidative stress and early apoptosis. In addition, we reported that FB1 exposure induced the accumulation of lysosome and occurrence of autophagy. Aberrant ER distribution and ER stress were also found in FB1-exposed oocytes. Moreover, DNA damage was also observed. These results together suggested that FB1 exposure affected oocyte quality by destroying spindle structure, leading to mitochondria, lysosome and ER dysfunction, which further induced oxidative stress, apoptosis, autophagy and DNA damage in mouse oocytes.


Assuntos
Fumonisinas , Animais , Apoptose , Dano ao DNA , Fumonisinas/toxicidade , Camundongos , Mitocôndrias/metabolismo , Oócitos/metabolismo , Estresse Oxidativo
19.
Nutrients ; 13(8)2021 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-34444947

RESUMO

Chronic obstructive pulmonary disease (COPD) is a respiratory disease associated with airways inflammation and lung parenchyma fibrosis. The primary goals of COPD treatment are to reduce symptoms and risk of exacerbations, therefore pulmonary rehabilitation is considered the key component of managing COPD patients. Oxidative airway damage, inflammation and reduction of endogenous antioxidant enzymes are known to play a crucial role in the pathogenesis of COPD. Recently, also natural antioxidants have been considered as they play an important role in metabolism, DNA repair and fighting the effects of oxidative stress. In this paper we evaluated the response of 105 elderly COPD patients to pulmonary rehabilitation (PR), based on high or low vegetable consumption, by analyzing clinical parameters and biological measurements at baseline and after completion of the three weeks PR. We found that daily vegetable intake in normal diet, without any specific intervention, can increase the probability to successfully respond to rehabilitation (65.4% of responders ate vegetables daily vs. 40.0% of non-responders, p = 0.033). The association was especially evident in subjects ≥ 80 year of age (OR = 17.0; p < 0.019). Three weeks of pulmonary rehabilitation are probably too short to reveal a reduction of the oxidative stress and DNA damage, but are enough to show an improvement in the patient's inflammatory state.


Assuntos
Dieta Saudável/métodos , Ingestão de Alimentos/fisiologia , Fenômenos Fisiológicos da Nutrição do Idoso/fisiologia , Doença Pulmonar Obstrutiva Crônica/reabilitação , Verduras , Administração por Inalação , Corticosteroides/administração & dosagem , Idoso , Idoso de 80 Anos ou mais , Broncodilatadores/administração & dosagem , Dano ao DNA/fisiologia , Inquéritos sobre Dietas , Feminino , Humanos , Inflamação , Pulmão/metabolismo , Masculino , Estresse Oxidativo/fisiologia , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Resultado do Tratamento
20.
Int J Mol Sci ; 22(16)2021 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-34445206

RESUMO

UV-induced DNA damage response and repair are extensively studied processes, as any malfunction in these pathways contributes to the activation of tumorigenesis. Although several proteins involved in these cellular mechanisms have been described, the entire repair cascade has remained unexplored. To identify new players in UV-induced repair, we performed a microarray screen, in which we found SerpinB10 (SPB10, Bomapin) as one of the most dramatically upregulated genes following UV irradiation. Here, we demonstrated that an increased mRNA level of SPB10 is a general cellular response following UV irradiation regardless of the cell type. We showed that although SPB10 is implicated in the UV-induced cellular response, it has no indispensable function in cell survival upon UV irradiation. Nonetheless, we revealed that SPB10 might be involved in delaying the duration of DNA repair in interphase and also in S-phase cells. Additionally, we also highlighted the interaction between SPB10 and H3. Based on our results, it seems that SPB10 protein is implicated in UV-induced stress as a "quality control protein", presumably by slowing down the repair process.


Assuntos
Dano ao DNA , Reparo do DNA/efeitos da radiação , Fase S/efeitos da radiação , Serpinas/metabolismo , Raios Ultravioleta/efeitos adversos , Linhagem Celular Tumoral , Humanos , Serpinas/genética
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