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4.
J Photochem Photobiol B ; 203: 111748, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31918235

RESUMEN

Nanotechnology is an emerged field to develop the plant mediated metal based nanodrugs by green method. In this current study, the zinc oxide metal based nanoparticles were developed using (Clausena lansium (Lour.) Skeels) Peel aqueous extracts and zinc nitrate. The C.L extract zinc nanoparticleswere indicated by the sharp peak seen at 350 nm utilizing the Ultraviolet-Visible spectroscopy (UV-Vis). The high peaks indicate the presence of phytochemicals and its functional groups in ZnONPs were studied by the Fourier Transform Infrared Spectroscopy (FT-IR). The X-Ray Diffraction analysis (XRD) explores the pattern and structure of ZnONPs as spherical and base-centered monoclinic crystalline shapes. The C.L extract with Zn nanoparticles were spherical in nature and the size of the synthesized particles were about 28.42 nm respectively. The autophagy (Beclin-1, LC3-I, LC3-II and ATG4B) and apoptotic (Bax, Bcl-2 and Caspase-3) proteins were regulated by the treatment with ZnONPs in SH-SY5Y neuroblastoma cells. The DNA loss or damage was occurred in the ZnONPs treatment and it was performed using Comet assay. The ZnONPs treatment generates the ROS in the cells and decreased its stability and viability. Addition of NAC prevents ROS in the cultured SH-SY5Y cells and prevents the cells from the apoptosis. We concluded that the ZnONPs potentially kills the neuroblastoma cells by producing the intracellular ROS.


Asunto(s)
Antineoplásicos/farmacología , Autofagia/efectos de los fármacos , Nanopartículas del Metal/química , Óxido de Zinc/química , Antineoplásicos/química , Apoptosis/efectos de los fármacos , Beclina-1/metabolismo , Caspasa 3/metabolismo , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Clausena/química , Clausena/metabolismo , Daño del ADN/efectos de los fármacos , Tecnología Química Verde , Humanos , Nanopartículas del Metal/toxicidad , Neuroblastoma/metabolismo , Neuroblastoma/patología , Extractos Vegetales/química , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Especies Reactivas de Oxígeno/metabolismo
5.
Chemosphere ; 242: 125286, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31896186

RESUMEN

Bisphenol-B (BPB), an analogue of bisphenol-A is used in the plastic industry. It has been found to leach from plastic containers leading to its contamination in canned food products. Moreover, it has also been detected in human samples such as sera and urine. BPB is recognized as a potential endocrine disrupting chemical owing to its estrogenic and anti-androgenic nature. Therefore, it was pertinent to study the effect of BPB exposure during the adolescence age (5-6 weeks old) in male mice. Weekly intraperitoneal injections of 5, 10 and 15% LD50 of BPB were given for 2 weeks to acute exposure groups and for 4 weeks to sub-acute exposure groups. BPB exposure induces change in enzymatic and non-enzymatic oxidative stress markers in sperm samples. DNA damage was also observed in sperm cells on acute and sub-acute exposures. Furthermore, BPB exposure led to a marked decline in sperm count and compromised sperm morphology. Computer assisted sperm analysis (CASA) revealed a significant decrease in sperm quality and progressive motility. Thus, both the acute and sub-acute exposures of adolescent male mice to BPB adversely affect the sperms' quality, functions and morphology.


Asunto(s)
Compuestos de Bencidrilo/toxicidad , Daño del ADN , Disruptores Endocrinos/toxicidad , Contaminantes Ambientales/toxicidad , Estrés Oxidativo/efectos de los fármacos , Fenoles/toxicidad , Espermatozoides/efectos de los fármacos , Factores de Edad , Animales , Humanos , Masculino , Ratones , Oxidación-Reducción , Recuento de Espermatozoides , Espermatozoides/patología , Pruebas de Toxicidad Aguda , Pruebas de Toxicidad Subaguda
6.
Toxicol Lett ; 322: 20-31, 2020 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-31923465

RESUMEN

Particulate matter (PM) from combustion processes has been associated with oxidative stress to DNA, whereas effects related to telomere dysfunction are less investigated. We collected air-borne PM from a passenger cabin of a diesel-propelled train and at a training facility for smoke diving exercises. Effects on oxidative stress biomarkers, genotoxicity measured by the comet assay and telomere length in PM-exposed A549 cells were compared with the genotoxicity and telomere length in peripheral blood mononuclear cells (PBMCs) from human volunteers exposed to the same aerosol source. Although elevated levels of DNA strand breaks and oxidatively damaged DNA in terms of Fpg-sensitive sites were observed in PBMCs from exposed humans, the PM collected at same locations did not cause genotoxicity in the comet assay in A549 cells. Nevertheless, A549 cells displayed telomere length shortening after four weeks exposure to PM. This is in line with slightly shorter telomere length in PBMCs from exposed humans, although it was not statistically significant. In conclusion, the results indicate that genotoxic potency measured by the comet assay of PM in A549 cells may not predict genotoxicity in exposed humans, whereas telomere length measurements may be a novel indicator of genotoxic stress in cell cultures and humans.


Asunto(s)
Daño del ADN , Exposición por Inhalación/efectos adversos , Material Particulado/toxicidad , Humo/efectos adversos , Homeostasis del Telómero/efectos de los fármacos , Emisiones de Vehículos/toxicidad , Células A549 , Contaminantes Ocupacionales del Aire/toxicidad , Supervivencia Celular/efectos de los fármacos , Bomberos , Humanos , Exposición por Inhalación/análisis , Leucocitos Mononucleares/efectos de los fármacos , Leucocitos Mononucleares/patología , Exposición Profesional/efectos adversos , Exposición Profesional/análisis , Estrés Oxidativo/efectos de los fármacos , Estrés Oxidativo/genética , Tamaño de la Partícula , Homeostasis del Telómero/genética
7.
Adv Exp Med Biol ; 1217: 225-239, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31898231

RESUMEN

DNA damage occurs in a human cell at an average frequency of 10,000 incidences per day by means of external and internal culprits, damage that triggers sequential cellular responses and stalls the cell cycle while activating specific DNA repair pathways. Failure to remove DNA lesions would compromise genomic integrity, leading to human diseases such as cancer and premature aging. If DNA damage is extensive and cannot be repaired, cells undergo apoptosis. DNA damage response (DDR) often entails posttranslational modifications of key DNA repair and DNA damage checkpoint proteins, including phosphorylation and ubiquitination. Cullin-RING ligase 4 (CRL4) enzyme has been found to target multiple DDR proteins for ubiquitination. In this chapter, we will discuss key repair and checkpoint proteins that are subject to ubiquitin-dependent regulation by members of the CRL4 family during ultraviolet light (UV)-induced DNA damage.


Asunto(s)
Daño del ADN , Reparación del ADN , Ubiquitina-Proteína Ligasas/metabolismo , Ubiquitina/metabolismo , Ubiquitinación , Envejecimiento/genética , Envejecimiento/patología , Animales , Apoptosis , Humanos , Neoplasias/genética , Neoplasias/patología
8.
Forensic Sci Int ; 306: 110077, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31821940

RESUMEN

Forensic samples are commonly influenced by various environmental factors, including ultraviolet (UV) irradiation; thus, forensic applications of DNA repair (e.g., PreCR™, Restorase®) have been investigated, focusing on short tandem repeat typing. However, current DNA-based examinations are used for both human and body fluid identification. This study thus aims to clarify the efficacy of a DNA repair approach for Streptococcus salivarius DNA-based identification of saliva from UV-damaged samples. Artificial UV-damaged genomic DNA of S. salivarius, drop saliva stains, and buccal swabs were used to evaluate the effects of DNA repair on S. salivarius DNA detection by using PreCR™ repair reagent. To evaluate forensic applications, we prepared mock forensic samples by exposing them to environmental conditions. Melting curve analysis following real-time PCR was applied for qualitatively detecting S. salivarius DNA with a specific melting peak of 80.5°C±0.4°C (n=10, mean ± 3SD). Single PCR was used for quantitative and qualitative analyses, whereas dual PCR was used for S. salivarius DNA qualitative detection. DNA repair experiments using artificial UV-damaged samples revealed a significant increase of only the quantitative value of genomic DNA samples by DNA repair. Moreover, significant quantitative DNA repair effects were not observed in all mock forensic samples, indicating the limitations of DNA repair for actual cell-derived DNA samples. Whereas, differences of qualitative results (with or without detection) were generated for mock forensic samples; thus, we consider the DNA repair strategy as an additional approach for S. salivarius DNA-based identification of saliva from environmentally damaged evidence.


Asunto(s)
Reparación del ADN , Saliva/microbiología , Streptococcus salivarius/genética , Rayos Ultravioleta/efectos adversos , Daño del ADN , ADN Bacteriano/genética , Humanos , Indicadores y Reactivos , Repeticiones de Microsatélite , Reacción en Cadena en Tiempo Real de la Polimerasa
9.
J Photochem Photobiol B ; 202: 111699, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31756585

RESUMEN

In this work, we propose a novel application of ERIC-PCR technique to study DNA damage after ultraviolet radiation (UV) and peracetic acid (PAA) treatment for water disinfection purpose. The efficacy of both treatments on E. coli suspension was evaluated by two approaches: through monitoring of inactivation by conventional culture technique, and by analyzing DNA damage with ERIC-PCR. All the experiments were carried out in a batch reactor, using three intensities of UV-C radiation (10.5, 4.2 and 2.1 mW/cm2) and different PAA concentrations (4 to 16 ppm). Both treatments produced bacterial inactivation in a dose-response fashion. Based on the results of bacterial count we obtained an index of inactivation (INACI). For each sample, DNA extraction was performed and evaluated by ERIC-PCR. Qualitative modifications were observed in ERIC-PCR band patterns for all the UV-C radiation intensities used, but no changes were detected at any of the PAA concentrations. The banding pattern modifications observed are consequence of the interruption of Taq polymerase enzyme amplification-activity, caused by the presence of alterations on the DNA structure (dimer and hydrates formation). Furthermore, an index was proposed to measure DNA damage (DNADI) regarding the changes in the relative optical density values of the amplification products. A linear correlation was obtained with a high correspondence between the inactivation index (INACI) and the DNA damage index (DNADI), that was expressed as DNADI = 0.05881×INACI. This approach proves that ERIC-PCR is a feasible and valuable tool for detecting and quantifying DNA damage and it may provide a useful strategy for bacterial identification, tracking changes in DNA and providing reliable and reproducible data.


Asunto(s)
Daño del ADN , Enterobacteriaceae/genética , Purificación del Agua/métodos , Daño del ADN/efectos de los fármacos , Daño del ADN/efectos de la radiación , ADN Bacteriano/química , ADN Bacteriano/metabolismo , Desinfección/métodos , Ácido Peracético/farmacología , Reacción en Cadena de la Polimerasa , Rayos Ultravioleta
10.
Cell Mol Life Sci ; 77(1): 3-18, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31748913

RESUMEN

Homologous recombination (HR) is a pathway to faithfully repair DNA double-strand breaks (DSBs). At the core of this pathway is a DNA recombinase, which, as a nucleoprotein filament on ssDNA, pairs with homologous DNA as a template to repair the damaged site. In eukaryotes Rad51 is the recombinase capable of carrying out essential steps including strand invasion, homology search on the sister chromatid and strand exchange. Importantly, a tightly regulated process involving many protein factors has evolved to ensure proper localisation of this DNA repair machinery and its correct timing within the cell cycle. Dysregulation of any of the proteins involved can result in unchecked DNA damage, leading to uncontrolled cell division and cancer. Indeed, many are tumour suppressors and are key targets in the development of new cancer therapies. Over the past 40 years, our structural and mechanistic understanding of homologous recombination has steadily increased with notable recent advancements due to the advances in single particle cryo electron microscopy. These have resulted in higher resolution structural models of the signalling proteins ATM (ataxia telangiectasia mutated), and ATR (ataxia telangiectasia and Rad3-related protein), along with various structures of Rad51. However, structural information of the other major players involved, such as BRCA1 (breast cancer type 1 susceptibility protein) and BRCA2 (breast cancer type 2 susceptibility protein), has been limited to crystal structures of isolated domains and low-resolution electron microscopy reconstructions of the full-length proteins. Here we summarise the current structural understanding of homologous recombination, focusing on key proteins in recruitment and signalling events as well as the mediators for the Rad51 recombinase.


Asunto(s)
Daño del ADN , Mapas de Interacción de Proteínas , Reparación del ADN por Recombinación , Animales , Proteínas de la Ataxia Telangiectasia Mutada/química , Proteínas de la Ataxia Telangiectasia Mutada/metabolismo , Proteína BRCA1/química , Proteína BRCA1/metabolismo , Proteína BRCA2/química , Proteína BRCA2/metabolismo , ADN/química , ADN/genética , Humanos , Modelos Moleculares , Conformación Proteica , Recombinasa Rad51/química , Recombinasa Rad51/metabolismo
11.
J Photochem Photobiol B ; 202: 111685, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31810035

RESUMEN

Surface tailored GaAu loaded mesoporous silica nanoparticles are considered as an important nanomaterial for biomedical applications such as diagnosis and cancer treatment. In this study, we used GaAu loaded mesoporous silica nanoparticles (Ga-Au@mSiO2) for the photothermal treatment of two prostate cancer cell lines. We systematically examined the nanocomposite form by various spectroscopic (UV-Vis, TGA and DTA) and electroscopic techniques (TEM and SEM including the elemental mapping analysis). After careful evaluation of the nanocomposite form, we performed cancer cell growth inhibition properties of the prostate cancer cell lines (DU145 and LNCaP). Also, we performed the photothermal effects of these nanocomposites on cell proliferation and apoptosis using different biochemical staining and flow cytometry. Our in vitro investigational datas are established Ga-Au@mSiO2 effectively exhibited and also with Ga-Au@mSiO2 + NIR the photothermal conversion therapy improved prostate cancer cells abolishing the prostate cancer cells. Interestingly, Ga-Au@mSiO2 + NIR was found to surpass the activity of Ga-Au@mSiO2 in all the cancer cells tested a topnotches. Hence, our current results demonstrated that surface tailored GaAu loaded mesoporous silica nanoparticles significantly inhibited the growth of prostate cancer cell lines and shown prominent antitumor effect in vitro. Thus, our study suggests that Ga-Au@mSiO2 + NIR could be used as impending anticancer candidate for photothermal ablation of prostate cancer cells. Further examinations of the mechanism indicated that anticancer activity was accomplished by inducing apoptosis in cancer cells, which is suggesting that these Ga-Au@mSiO2 + NIR nanocomposite can be used as promising candidates for nursing care cancer therapy.


Asunto(s)
Galio/química , Oro/química , Rayos Infrarrojos , Nanocompuestos/química , Neoplasias de la Próstata/terapia , Apoptosis/efectos de los fármacos , Apoptosis/efectos de la radiación , Puntos de Control del Ciclo Celular/efectos de los fármacos , Puntos de Control del Ciclo Celular/efectos de la radiación , Línea Celular Tumoral , Daño del ADN/efectos de los fármacos , Daño del ADN/efectos de la radiación , Humanos , Masculino , Nanocompuestos/uso terapéutico , Nanocompuestos/toxicidad , Atención de Enfermería , Fototerapia , Porosidad , Neoplasias de la Próstata/patología , Dióxido de Silicio/química
12.
Toxicol Lett ; 319: 102-110, 2020 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-31706006

RESUMEN

Crizotinib is a multi-target receptor tyrosine kinase inhibitor which is of great importance for the management of ALK-rearranged non-small cell lung cancer (NSCLC) patients. Serious erythroderma and toxic epidermal necrolysis have been reported associated with crizotinib treatment. The underlying mechanisms have not been examined. In this study, we tested the toxicity of crizotinib on immortal human keratinocytes (HaCaT) and human primary keratinocytes. We found that crizotinib directly cause cytotoxic on these two cells, which could be the explanation of the clinical characteristic of pathology. Apoptosis was observed and Z-VAD-FMK, a pan-caspase inhibitor can almost totally reverse the apoptosis induction effect of crizotinib. However, mitochondrial dysfunction and DNA damage were not involved in crizotinib-induced apoptosis, indicating the intrinsic apoptosis pathway have no connection with this cutaneous toxicity. Further studies showed that crizotinib significantly increased cleaved-caspase-8, a signaling protein of extrinsic apoptosis pathway, in a concentration and time-dependent manner. Moreover, we found the targets of crizotinib were not involved in HaCaT cells apoptosis. Collectively, our findings first report keratinocytes apoptosis is the key cause of crizotinib-induced cutaneous toxicity. We also reveal crizotinib induce apoptosis through the extrinsic apoptosis pathway due to detected up-regulated cleaved-caspase-8. Meanwhile, the apoptosis is independent of mitochondrial dysfunction, DNA damage and related drug targets inhibition.


Asunto(s)
Antineoplásicos/toxicidad , Apoptosis/efectos de los fármacos , Crizotinib/toxicidad , Dermatitis Exfoliativa/inducido químicamente , Queratinocitos/efectos de los fármacos , Clorometilcetonas de Aminoácidos/farmacología , Caspasa 8/metabolismo , Inhibidores de Caspasas/farmacología , Línea Celular , Daño del ADN , Dermatitis Exfoliativa/patología , Humanos , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Cultivo Primario de Células , Especies Reactivas de Oxígeno/metabolismo , Transducción de Señal/efectos de los fármacos
13.
Gene ; 726: 144135, 2020 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-31589958

RESUMEN

Lon is a major ATP-dependent protease of E. coli involved in degradation of abnormal misfolded proteins and specific regulatory proteins. Absence of Lon in E. coli results in sensitivity to DNA damaging agents and over-production of capsular polysaccharide due to accumulation of Lon substrates, SulA (cell division inhibitor induced upon DNA damage) and RcsA (activator of cps genes), respectively. In a previous study, we identified that a G232D mutation, termed faa (for function affecting alternative-lon-protease), in the E. coli co-chaperone DnaJ, results in suppression of lon mutant phenotypes. Additionally, inactivation of the trans-translation system was found to have an additive effect on faa activity. In the present work, we employed random mutagenesis approach to isolate novel mutations in dnaJ which could phenotypically compensate the absence of Lon. Using a lacZ-based Lon reporter strain, we were able to isolate two new mutations in dnaJ as lon suppressors. These mutations, namely, flm-1 (H33Y) and flm-2 (P34S), affected the highly conserved HPD motif of DnaJ. Both mutations suppressed lon phenotypes to variable extent and the suppression was also differentially modulated by mutations in ssrA that affect trans-translation. We show that ClpYQ protease up-regulated in both mutants should degrade SulA, since inactivation of clpQ abolished the resistance to DNA damaging agents. On the other hand, we found suppression of capsule overproduction phenotype was independent of ClpYQ in both mutants but resulted due to down-regulation of rcsA in flm-1. Thus, our findings highlight the intricate redundancy of cellular proteolysis networks in bacteria which can compensate the absence of Lon via distinct mechanisms.


Asunto(s)
Daño del ADN/genética , Endopeptidasa Clp/genética , Proteínas de Escherichia coli/genética , Escherichia coli/genética , Proteínas del Choque Térmico HSP40/genética , Mutación/genética , Proteasa La/genética , Regulación hacia Abajo/genética , Fenotipo , Proteolisis , Regulación hacia Arriba/genética
14.
HNO ; 68(1): 8-13, 2020 Jan.
Artículo en Alemán | MEDLINE | ID: mdl-31511908

RESUMEN

BACKGROUND: While an abundant number of studies concerning tobacco smoke and chewing tobacco show carcinogenic potential, there is little data on the consequences of snuff, especially on the cellular level. Therefore, the mutagenic effect of snuff is difficult to estimate and the WHO assessment of snuff being not carcinogenic is based on very limited data. OBJECTIVES: This paper investigates the potential cytotoxic and genotoxic effects of snuff on human lymphocytes and nasal mucosa cells. MATERIALS AND METHODS: Two types of snuff were used: one without menthol and one with a high degree of menthol. The necessary nasal mucosa cells and lymphocytes were collected from 10 subjects undergoing nasal obstruction surgery and incubated for one hour with a snuff-DMSO mixture (range 0.01-2000 µg/ml). Methods included the trypan blue test, the comet assay, and the micronucleus test. RESULTS: The trypan blue test showed no decrease in cell viability for either cell type. The comet assay revealed a significant increase in the Olive Tail Moment for lymphocytes starting at 100 µg/ml and at 1000 µg/ml for nasal mucosa cells. There was no significant increase in micronuclei according to the micronucleus test. No differences between these two types of tobacco were observed. CONCLUSION: The present study demonstrated genotoxic damage, such as DNA strand breaks, which may be repaired, but no non-repairable elevated micronuclei. The present findings cast doubts on the WHO assessment that snuff is not carcinogenic. However, for a sound assessment of the risk potential of snuff, further research on various genotoxic endpoints in human cells is warranted.


Asunto(s)
Linfocitos , Mucosa Nasal , Tabaco sin Humo , Ensayo Cometa , Daño del ADN , Humanos , Linfocitos/efectos de los fármacos , Mucosa Nasal/efectos de los fármacos , Tabaco sin Humo/efectos adversos
15.
Toxicol Lett ; 319: 58-65, 2020 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-31730884

RESUMEN

This study proposes the application of the comet assay for the evaluation of DNA damage from frozen human whole blood samples that could be readily used in human biomonitoring and epidemiological studies. It was done on simply frozen whole blood samples collected from male volunteers (N = 60) aliquoted in small volumes and stored at -80 °C without the addition of cryopreservatives for a period of 5 years. To test the applicability of the alkaline comet assay for the evaluation of DNA damage in frozen whole blood, samples were quickly thawed at 37 °C and immediately embedded in an agarose matrix followed by an alkaline comet assay procedure. We concluded that the whole blood freezing and prolonged storage do not severely affect comet assay values, although background values were higher compared to our historical control data from the fresh whole blood. Even the influence of the variables tested, such as age, body mass index, smoking habit and alcohol consumption were in agreement with our previous data using fresh blood. The obtained results suggest that the comet assay could be applied to frozen blood samples, if properly stored, even for decades, which would certainly facilitate large-scale human biomonitoring and long-term epidemiological studies.


Asunto(s)
Conservación de la Sangre/efectos adversos , Sangre , Ensayo Cometa/métodos , Daño del ADN , Adolescente , Adulto , Factores de Edad , Anciano , Índice de Masa Corporal , Criopreservación , Congelación , Humanos , Estilo de Vida , Masculino , Persona de Mediana Edad , Monitoreo Fisiológico , Adulto Joven
16.
Cell Mol Life Sci ; 77(1): 19-33, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31754726

RESUMEN

DNA damage response (DDR) relies on swift and accurate signaling to rapidly identify DNA lesions and initiate repair. A critical DDR signaling and regulatory molecule is the posttranslational modification poly(ADP-ribose) (PAR). PAR is synthesized by a family of structurally and functionally diverse proteins called poly(ADP-ribose) polymerases (PARPs). Although PARPs share a conserved catalytic domain, unique regulatory domains of individual family members endow PARPs with unique properties and cellular functions. Family members PARP-1, PARP-2, and PARP-3 (DDR-PARPs) are catalytically activated in the presence of damaged DNA and act as damage sensors. Family members tankyrase-1 and closely related tankyrase-2 possess SAM and ankyrin repeat domains that regulate their diverse cellular functions. Recent studies have shown that the tankyrases share some overlapping functions with the DDR-PARPs, and even perform novel functions that help preserve genomic integrity. In this review, we briefly touch on DDR-PARP functions, and focus on the emerging roles of tankyrases in genome maintenance. Preservation of genomic integrity thus appears to be a common function of several PARP family members, depicting PAR as a multifaceted guardian of the genome.


Asunto(s)
Daño del ADN , Reparación del ADN , Inestabilidad Genómica , Poli(ADP-Ribosa) Polimerasas/metabolismo , Animales , Humanos , Modelos Moleculares , Poli(ADP-Ribosa) Polimerasas/química , Dominios Proteicos , Tanquirasas/química , Tanquirasas/metabolismo
17.
Chemosphere ; 240: 124910, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31561159

RESUMEN

The micronucleus test has been applied for more than three decades in tadpoles, generating an early warning of environmental quality. In this study, we reviewed 48 articles on the micronucleus test in tadpoles, published between 1987 and 2018. The findings reveal that pesticides have been the main topic discussed in the induction of micronucleus and other nuclear abnormalities in anuran larvae to the detriment of the widespread use of compounds used in agriculture. In addition to pesticides, a number of other xenobiotic agents have been targeted for genotoxic damage, such as heavy metals, radiation and wastewater. An appeal is reported to environmental contaminants, which when released naturally into the environment or because of human activities may contaminate aquatic habitats, threatening populations of tadpoles that depend on these environments for their survival. Larvae can bioaccumulate these contaminants that cause progressive impacts, ranging from DNA damage to metamorphosis delays, as well as malformations. We found that Argentina is the main driving force for the application of this test in anuran larvae along with Brazil. Different erythrocyte malformations have been reported for the erythrocyte nuclear abnormalities test, binucleated cells, nuclear buds, notched, lobed, reniform, nuclear bebbled, anucleated, picnotic and apoptotic cells are the most cited. In summary, the presence of chemical or physical agents, along with other disturbances of the habitat, can have a significant impact on the life history of the species, contributing to the decline of anuran populations.


Asunto(s)
Anuros/genética , Ecotoxicología/tendencias , Eritrocitos/efectos de los fármacos , Larva/efectos de los fármacos , Larva/genética , Pruebas de Micronúcleos , Agricultura , Animales , Argentina , Brasil , Daño del ADN , Ecosistema , Monitoreo del Ambiente/métodos , Contaminación Ambiental , Eritrocitos/patología , Eritrocitos/fisiología , Metales Pesados/toxicidad , Metamorfosis Biológica/efectos de los fármacos , Publicaciones Seriadas , Contaminantes Químicos del Agua/toxicidad
18.
Chemosphere ; 240: 124919, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31726585

RESUMEN

Ionic liquids (ILs) are regarded as green solvents and are frequently used in the chemical industry. However, ILs may impact plant growth if they are present in the soil environment. To compare toxicity of ILs with different anions in soil, three imidazolium-based ionic liquids (1-hexyl-3-methylimidazolium bromide, 1-hexyl-3-methylimidazolium nitrate, 1-hexyl-3-methylimidazolium tetrafluoroborate) were used to assess impact on Vicia faba. Following 10 d of exposure to these three ILs from 0 to 2500 mg kg-1, shoot length, root length and dry weight of Vicia faba were determined. Pot trials revealed that ILs inhibited Vicia faba growth and according to EC50 values, [C6mim]BF4 was the most toxic one. In addition, physiological indicators of Vicia faba were determined following 10 d of exposure at selected IL concentrations (0, 1, 10, 100 and 500 mg kg-1). ILs led to the generation of reactive oxygen species and then caused oxidative damage, including lipid peroxidation, protein damage and DNA damage, which triggered an increase in antioxidant content and enzyme activity. The experimental results indicated that oxidative stress may be the primary underlying toxic mechanism for Vicia faba. Furthermore, based on the data of physiological experiment, integrated biomarker response (IBR) was calculated to compare the toxicity of the three ILs and toxic order was: [C6mim]NO3<[C6mim]Br<[C6mim]BF4.


Asunto(s)
Líquidos Iónicos/toxicidad , Vicia faba/efectos de los fármacos , Aniones/química , Antioxidantes/metabolismo , Biomarcadores/metabolismo , Boratos/toxicidad , Bromuros , Daño del ADN , Imidazoles/toxicidad , Peroxidación de Lípido , Nitratos/metabolismo , Estrés Oxidativo , Especies Reactivas de Oxígeno/metabolismo , Plantones/metabolismo , Suelo/química , Contaminantes del Suelo/metabolismo , Solventes/metabolismo , Pruebas de Toxicidad , Vicia faba/crecimiento & desarrollo
19.
Chemosphere ; 238: 124616, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31466003

RESUMEN

The Alagados Reservoir (Southern Brazil) is used as water supply, and since 2002 there have been reports with a presence of cyanobacterial blooms and cyanotoxins. In order to assess the water quality and the ecological integrity of the reservoir, we evaluated biochemical, genotoxic and osmoregulatory biomarkers in the freshwater cichlid fish (Geophagus brasiliensis) that were exposed to PSTs. The fish were sampled in the Alagados Reservoir in February 2016 (Summer) and were divided in three groups: 1) Reservoir group (RES): fish were collected immediately after sampling; 2) Depuration group (DEP): fish were submitted to the depuration experiment for 90 days in the laboratory; and 3) Reproduction group (REP): fish were kept in the laboratory until the fertilization and the chemical analyses were performed on the offspring (F1 generation). In the RES and DEP the blood, brain, muscle, liver and gills were collected for biochemical, genotoxic and osmoregulatory biomarkers analysis. Our results showed that the fish from the Alagados Reservoir (RES) presented oxidative stress and DNA damage; and after 90 days (DEP), the antioxidant system and DNA damage were recovered. Although PSTs were considered a risk to the ecological integrity of this water body; PSTs concentrations were not found in the tissues of the F1 generation. In addition, the biomarkers used were useful tools to evaluate the effects of environment contamination. Therefore, it is necessary to develop new technologies and monitoring programs in order to reduce cyanobaterial blooms, cyanotoxins and human activities that cause the contamination in aquatic environments.


Asunto(s)
Biomarcadores/análisis , Cíclidos/metabolismo , Daño del ADN/efectos de los fármacos , Alimentos Marinos/análisis , Toxinas Biológicas/análisis , Contaminantes Químicos del Agua/análisis , Animales , Cíclidos/crecimiento & desarrollo , Monitoreo del Ambiente , Humanos , Toxinas Biológicas/toxicidad , Contaminantes Químicos del Agua/toxicidad
20.
Chemosphere ; 240: 124880, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31542581

RESUMEN

Microginins (MGs) are bioactive metabolites mainly produced by Microcystis spp., (Cyanobacteria) commonly found in eutrophic environments. In this study, the cytotoxic and genotoxic activities of four MG congeners (MG FR3, MG GH787, cyanostatin B, MGL 402) and a well characterized cyanobacterial extract B-14-01 containing these metabolites were evaluated in the human hepatocellular carcinoma (HepG2) cell line. The cytotoxicity was measured with the MTT assay, while genotoxicity was studied with the comet, γH2AX and cytokinesis block (CBMN) micronucleus assays. The viability of cells after 24 h was significantly affected only by the extract, whereas after 72 h a concentration dependent decrease in cell proliferation was observed for the extract and tested microginins, with MGL 402 being the most potent and MG FR3 the least potent congener. The extract and all tested congeners induced DNA strand breaks after 4 and 24 h exposure. The most potent was the extract, which induced concentration and time dependent increase in DNA damage at concentrations ≥0.01 µg mL-1. Among microginins the most potent was MGL 402 (increase in DNA strand breaks at ≥ 0.01 µg mL-1) and MG FR3 was the least potent (increase in DNA strand breaks at ≥ 1 µg mL-1). However, no induction of DNA double strand breaks was observed after 24 and 72-h exposure to the cyanobacterial extract or MGs. Induction of genomic instability was observed in cells exposed to MG GH787, cyanostatin B and the extract B-14-01. This study is the first to provide the evidence that microginins exert genotoxic activity.


Asunto(s)
Carcinoma Hepatocelular/patología , Cianobacterias/metabolismo , Daño del ADN/genética , Inestabilidad Genómica , Neoplasias Hepáticas/patología , Oligopéptidos/farmacología , Carcinoma Hepatocelular/genética , Ensayo Cometa , Daño del ADN/efectos de los fármacos , Células Hep G2 , Humanos , Neoplasias Hepáticas/genética , Pruebas de Micronúcleos
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