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1.
Sci Total Environ ; 739: 140261, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32758962

RESUMO

The accumulation of anthropogenic chemical substances in aquatic organisms is an immensely important issue from the point of view of environmental protection. In the context of the increasing number and variety of compounds that may potentially enter the environment, there is a need for efficient and reliable solutions to assess the risks. However, the classic approach of testing with fish or other animals is not sufficient. Due to very high costs, significant time and labour intensity, as well as ethical concerns, in vivo methods need to be replaced by new laboratory-based tools. So far, many models have been developed to estimate the bioconcentration potential of chemicals. However, most of them are not sufficiently reliable and their predictions are based on limited input data, often obtained with doubtful quality. The octanol-water partition coefficient is still often used as the main laboratory tool for estimating bioconcentration. However, according to current knowledge, this method can lead to very unreliable results, both for neutral species and, above all, for ionic compounds. It is therefore essential to start using new, more advanced and credible solutions on a large scale. Over the last years, many in vitro methods have been newly developed or improved, allowing for a much more adequate estimation of the bioconcentration potential. Therefore, the aim of this work was to review the most recent laboratory methods for assessing the bioconcentration potential and to evaluate their applicability in further research.


Assuntos
Organismos Aquáticos , Poluentes Químicos da Água/análise , Animais , Bioacumulação , Peixes , Xenobióticos
2.
Chemosphere ; 257: 127060, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32505945

RESUMO

The aim of the present work is to evaluate the ability of 'fungi' for the biodegradation of recalcitrant xenobiotic compound, 'Atrazine' in batch liquid cultures. Different parameters like pH (2.0-8.0) temperature (16-32 °C), biomass (1-5 g), and concentration (25-100 ppm) were optimized for the efficient degradation of atrazine. The decomposition behavior of atrazine is analyzed with the help of Fourier Transform Infrared (FTIR) spectroscopy. Herein, we have reported that the Bjerkandera adusta possess high removal efficiency of the xenobiotic compound (atrazine) up to 92%. The fungal strain investigated could prove to be a valuable active pesticide degrading micro-organism, with high detoxification values. These results are useful for improved understanding and prediction of the behavior and fate of B. adusta in the bio-purification of wastewater contaminated with xenobiotics. Thus providing a new and green approach for the remediation of toxicants without altering the environmental components.


Assuntos
Atrazina/metabolismo , Coriolaceae/fisiologia , Xenobióticos/metabolismo , Biodegradação Ambiental , Biomassa , Coriolaceae/metabolismo , Águas Residuárias
3.
Ecotoxicol Environ Saf ; 201: 110811, 2020 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-32544744

RESUMO

Xenobiotic mediated renal toxicity is one of the major health concerns to the organisms, including humans. New chemicals with nephrotoxic potential are continuously being added to the list of existing nephrotoxicants. To predict the nephrotoxicity of these new chemicals, reliable and cost-effective alternative animal models are required. It is a prerequisite for the identification and assessment of these compounds as potential nephrotoxicants to prevent renal toxicity in the exposed population. Drosophila melanogaster, a genetically tractable invertebrate animal model, has a renal system functionally analogous to humans. The Malpighian tubules (MTs) of D. melanogaster are similar to the tubular part of nephron of the human kidney. Besides, it recapitulates the renal toxicity hallmark with mammals when exposed to known nephrotoxicants. In this study, first instar larvae of D. melanogaster (Oregon R) were exposed to different concentrations of two well-known nephrotoxicants, cadmium (Cd) and mercury (Hg). Akin to higher organisms, Cd and Hg exposure to D. melanogaster produce similar phenotypes. MTs of exposed D. melanogaster larvae exhibited increased oxidative stress, activated cellular antioxidant defense mechanism, GSH depletion, increased cleaved caspase-3 expression, increased DEVDase activity and increased cell death. The functional status of MTs was assessed by fluid secretion rate (FSR), efflux activity of transporter protein, mitochondrial membrane potential (MMP), ATP level and expression of junctional protein (Dlg). All the phenotypes observed in MTs of D. melanogaster larvae recapitulate the phenotypes observed in higher organisms. Increased uric acid level, the hallmark of renal dysfunction, was also observed in exposed larvae. Taken together, the study suggests that MTs of D. melanogaster may be used as a functional model to evaluate xenobiotic mediated nephrotoxicity.


Assuntos
Alternativas aos Testes com Animais , Cádmio/toxicidade , Drosophila melanogaster/efeitos dos fármacos , Rim/efeitos dos fármacos , Túbulos de Malpighi/efeitos dos fármacos , Mercúrio/toxicidade , Animais , Antioxidantes/metabolismo , Transporte Biológico , Cádmio/metabolismo , Humanos , Rim/metabolismo , Larva/efeitos dos fármacos , Túbulos de Malpighi/metabolismo , Mercúrio/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Xenobióticos/metabolismo , Xenobióticos/toxicidade
4.
Sci Total Environ ; 740: 139894, 2020 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-32562984

RESUMO

The development of multitarget and/or suspect screening methods for the analysis of xenobiotics in fish samples is compulsory due to the lack of works in the literature where a deep evaluation of the variables affecting extraction and clean-up steps is performed. The aim of the present work was to optimize and validate a multitarget (180 compounds) method for the analysis of priority and emerging xenobiotics in fish muscle using focused ultrasound-assisted solid-liquid extraction. From the different extraction solvents studied, a single extraction in cold acetonitrile rendered the best consensus results in terms of absolute recoveries and the number of target compounds extracted. Matrix effect was minimized using commercially available Captiva ND-Lipid filters, which provided clean extracts and satisfactory repeatability compared to other approaches. Absolute recoveries were corrected using matrix-matched calibration and apparent recoveries in the 43%-105%, 73%-131% and 78%-128% ranges were obtained at low (20 ng g-1), medium (100 ng g-1), and high (200 ng g-1) spiking levels, respectively. A 60% of the xenobiotics showed limits of identification lower than 20 ng g-1. The developed method was successfully applied to the quantification and suspect screening of samples bought in a local market (hake, gilt-head bream, sea bass and prawn) and fished (thicklip grey mullet) at the Urdaibai estuary (north of Spain). Food additives, antiparasitic drugs and PFOS were quantified at ng g-1 level. Moreover, the targeted method was extended to the suspect screening, revealing the presence of plastic related products (caprolactam, phthalates, polyethylenglycols), pharmaceutical products (albendazole, mebendazole, valpromide) and pesticides or insect repellents (icaridin, myristyl sulfate, nootkatone). Therefore, FUSLE in cold acetonitrile combined with Captiva ND-Lipid filters and liquid chromatography tandem high-resolution mass spectrometry (LC-q-Orbitrap) were successfully applied to both multitarget quantitative analysis and suspect screening of approx. 17,800 compounds.


Assuntos
Peixes , Músculos/química , Espectrometria de Massas em Tandem , Poluentes Químicos da Água/análise , Xenobióticos/análise , Animais , Extração em Fase Sólida , Espanha
5.
Sci Total Environ ; 741: 140058, 2020 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-32599397

RESUMO

Tetrahymena is a single-cell eukaryotic organism present in all aquatic environments and can easily be maintained in laboratory conditions in a cost-effective manner. This review gives a brief description of the physiology of Tetrahymena, culture handling, and maintenance of Tetrahymena species. The review article focuses on various toxicological bioassays at different biological organizational (biochemical, individual, population, and community) levels. Furthermore, some techniques such as single cell gel electrophoresis (SCGE) and microcalorimetry assay are also available to investigate the effect of xenobiotics on the integrity of DNA and metabolic state of Tetrahymena species respectively. The article also discusses how the general physiology, behavioural activities and different organelles of Tetrahymena could be useful in toxicological studies. The strength and limitations of Tetrahymena over other model organisms are also discussed. This article also provides suggestions to overcome some problems related to toxicity assessment. Various aspects associated with variability in results, toxicity endpoints, characteristics of organisms and responses against xenobiotic substances (old and new emerging toxicants) are considered.


Assuntos
Tetrahymena , Xenobióticos
6.
Phytochemistry ; 176: 112421, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32505862

RESUMO

The exponential industrial growth we see today rides on the back of large scale production of chemicals, explosives and pharmaceutical products. However, the effluents getting released from their manufacturing units are greatly compromising the sustainability of our environment. With greater awareness of the imperative for environmental clean-up, a promising approach that is attracting increasing research interests is biodegradation of xenobiotics. In this approach, biotransformation has proven to be one of the most effective tools. While many different model frameworks have been used to study different aspects of biotransformation, hairy roots (HRs) have been found to be exceptionally valuable. HR cultures are preferred over other in-vitro model systems due to their biochemical stability and hormone-autotrophy. In addition, the multi-enzyme biosynthetic potential of HRs which is similar to the parent plant and their relatively low-cost cultural requirements further characterize their suitability for biotransformation. The recent progress observed in scale-up of HR cultures and understanding of functional genomics has opened up new dimensions providing valuable insights for industrial application. This review article summarizes the potential of HR cultures in the biotransformation of xenobiotics, their limitations in the application on a large scale and current strategies to alleviate them. Advancement in bioreactors engineering enabling large scale cultivation and modern gene technologies improving biotransformation efficiency promises to extend laboratory results to industrial applications.


Assuntos
Raízes de Plantas , Xenobióticos , Biodegradação Ambiental , Reatores Biológicos , Biotransformação
7.
Aquat Toxicol ; 225: 105542, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32585539

RESUMO

Visual system is increasingly recognized as a sensitive target of xenobiotics in aquatic ecosystems. Various environmental pollutants of distinct physicochemical properties are able to impair the retinal development and function of teleost fishes, including dioxin-like pollutants, flame retardants, pesticides, perfluoroalkyl acids, retinoic acids and metals. Considering the availability of developmental and functional database, zebrafish has been the most frequently used as the teleost model to study aquatic visual toxicology. A diversity of visual deficits has been displayed for fishes across multiple levels of biological organizations (e.g., molecule, cell, histology, physiology and behavior). Covering sensitive developmental windows of eyes during early embryogenesis, acute or chronic exposure to xenobiotics can disturb the expressions of visual gene and protein markers, which affect the retinal neurogenesis and induce degeneration of neurons. Morphological structures and physiological responses of retina and optic tectum are then disorganized, eventually compromising the performance of visually-mediated behaviors and recruitment of individuals. Environmental pollutants can cross the blood-retina barrier and accumulate in eyes, which might impact visual system directly. In addition, pollutants are very likely to interrupt retinal development and function indirectly by disturbing the signaling of retinoids and thyroid. However, exact mechanisms of visual toxicity are largely unknown currently. In this review, the development and structure of retina and available tools for studying visual science are described briefly. Advances in visual toxicology are summarized in detail and outlooks for future visual toxicity studies are discussed.


Assuntos
Ecossistema , Poluentes Químicos da Água/toxicidade , Animais , Desenvolvimento Embrionário , Olho , Retardadores de Chama/toxicidade , Humanos , Neurogênese , Praguicidas , Xenobióticos , Peixe-Zebra
8.
Ecotoxicol Environ Saf ; 201: 110835, 2020 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-32563159

RESUMO

The activation of the aryl hydrocarbon receptor (AHR) occurs through the binding of dioxin-like compounds (DLCs) or natural ligands. In this pathway, the AHR-ARNT (AHR nuclear translocator) heterodimer serves to regulate critical physiological functions, such as immune responses and the metabolism of xenobiotics. Birds have three AHR isoforms (AHR1, AHR1ß, and AHR2) and two ARNT isoforms (ARNT1 and ARNT2). However, how AHR and ARNT dimerization pair in birds regulates the AHR signaling pathway in an isoform-specific manner remains unknown. In this study, we initially sought to clarify the major chicken AHR-ARNT (ckAHR-ckARNT) pairs by estimating the mRNA tissue distributions of various ckAHR and ckARNT isoforms. Our results indicated that the ckAHR1-ckARNT1 represented the major dimerization pair in most tissues except the brain. We then measured the transactivation potencies of various ckAHR-ckARNT pairs by natural ligands and 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), in in vitro reporter gene assays using COS-7 and LMH cell lines. Our results from the in vitro assays demonstrated that the ckAHR1-ckARNT1 pair was strongly activated by the five natural ligands, namely, 6-formylindolo [3,2-b]carbazole, L-kynurenin, kynurenic acid, indoxyl-3-sulfate, and 1,3,7-tribromodibenzo-p-dioxin, but not by TCDD. In in silico ligand docking simulations with ckAHR1 homology models, all the natural ligands showed a interaction pattern that was distinct from that observed with anthropogenic DLCs, including TCDD. In conclusion, our findings indicate that the ckAHR1-ckARNT1 may be the most important dimerization pair in most tissues for regulating the physiological functions driven by natural ligands, although it was less reactive to TCDD.


Assuntos
Translocador Nuclear Receptor Aril Hidrocarboneto/metabolismo , Galinhas/metabolismo , Dibenzodioxinas Policloradas/metabolismo , Multimerização Proteica , Receptores de Hidrocarboneto Arílico/metabolismo , Xenobióticos/metabolismo , Animais , Translocador Nuclear Receptor Aril Hidrocarboneto/genética , Células COS , Linhagem Celular Tumoral , Chlorocebus aethiops , Simulação por Computador , Ligantes , Simulação de Acoplamento Molecular , Ligação Proteica , Isoformas de Proteínas , Receptores de Hidrocarboneto Arílico/genética , Transdução de Sinais , Especificidade da Espécie , Transfecção
9.
Aquat Toxicol ; 225: 105540, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32569997

RESUMO

The zebrafish (Danio rerio) embryo has increasingly been used as an alternative model in human and environmental toxicology. Since the cytochrome P450 (CYP) system is of fundamental importance for the understanding and correct interpretation of the outcome of toxicological studies, constitutive and xenobiotic-induced 7-methoxycoumarin-O-demethylase (MCOD), i.e. 'mammalian CYP2-like', activities were monitored in vivo in zebrafish embryos via confocal laser scanning microscopy. In order to elucidate molecular mechanisms underlying the MCOD induction, dose-dependent effects of the prototypical CYP inducers ß-naphthoflavone (aryl hydrocarbon receptor (AhR) agonist), rifampicin (pregnane X receptor (PXR) agonist), carbamazepine and phenobarbital (constitutive androstane receptor (CAR) agonists) were analyzed in zebrafish embryos of varying age. Starting from 36 h of age, all embryonic stages of zebrafish could be shown to have constitutive MCOD activity, albeit with spatial variation and at distinct levels. Whereas carbamazepine, phenobarbital and rifampicin had no effect on in vivo MCOD activity in 96 h old zebrafish embryos, the model aryl hydrocarbon receptor agonist ß-naphthoflavone significantly induced MCOD activity in 96 h old zebrafish embryos at 46-734 nM, however, without a clear concentration-effect relationship. Induction of MCOD activity by ß-naphthoflavone gradually decreased with progression of embryonic development. By in vivo characterization of constitutive and xenobiotic-induced MCOD activity patterns in 36, 60, 84 and 108 h old zebrafish embryos, this decrease could primarily be attributed to an age-related decline in the induction of MCOD activity in the cardiovascular system. Results of this study provide novel insights into the mechanism and extent, by which specific CYP activities in early life-stages of zebrafish can be influenced by exposure to xenobiotics. The study thus lends further support to the view that zebrafish embryos- at least from an age of 36 h - have an elaborate and inducible biotransformation system.


Assuntos
Sistema Enzimático do Citocromo P-450/biossíntese , Embrião não Mamífero/efeitos dos fármacos , Oxirredutases O-Desmetilantes/biossíntese , Poluentes Químicos da Água/toxicidade , Peixe-Zebra/metabolismo , Animais , Biotransformação , Indutores das Enzimas do Citocromo P-450/toxicidade , Embrião não Mamífero/enzimologia , Desenvolvimento Embrionário/efeitos dos fármacos , Receptores de Hidrocarboneto Arílico/metabolismo , Xenobióticos/toxicidade , Proteínas de Peixe-Zebra/metabolismo , beta-Naftoflavona/toxicidade
10.
Food Chem Toxicol ; 141: 111418, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: covidwho-345861

RESUMO

Occupational, residential, dietary and environmental exposures to mixtures of synthetic anthropogenic chemicals after World War II have a strong relationship with the increase of chronic diseases, health cost and environmental pollution. The link between environment and immunity is particularly intriguing as it is known that chemicals and drugs can cause immunotoxicity (e.g., allergies and autoimmune diseases). In this review, we emphasize the relationship between long-term exposure to xenobiotic mixtures and immune deficiency inherent to chronic diseases and epidemics/pandemics. We also address the immunotoxicologic risk of vulnerable groups, taking into account biochemical and biophysical properties of SARS-CoV-2 and its immunopathological implications. We particularly underline the common mechanisms by which xenobiotics and SARS-CoV-2 act at the cellular and molecular level. We discuss how long-term exposure to thousand chemicals in mixtures, mostly fossil fuel derivatives, exposure toparticle matters, metals, ultraviolet (UV)-B radiation, ionizing radiation and lifestyle contribute to immunodeficiency observed in the contemporary pandemic, such as COVID-19, and thus threaten global public health, human prosperity and achievements, and global economy. Finally, we propose metrics which are needed to address the diverse health effects of anthropogenic COVID-19 crisis at present and those required to prevent similar future pandemics.


Assuntos
Poluentes Atmosféricos/toxicidade , Betacoronavirus , Infecções por Coronavirus/epidemiologia , Praguicidas/toxicidade , Pneumonia Viral/epidemiologia , Xenobióticos/toxicidade , Animais , Antivirais/uso terapêutico , Infecções por Coronavirus/tratamento farmacológico , Infecções por Coronavirus/fisiopatologia , Dieta , Epidemias , Humanos , Sistema Imunitário/efeitos dos fármacos , Pandemias , Pneumonia Viral/tratamento farmacológico , Pneumonia Viral/fisiopatologia , Prevalência , Receptores de Hidrocarboneto Arílico/metabolismo , Fatores de Risco , Transdução de Sinais/efeitos dos fármacos , Tempo
11.
Science ; 368(6491): 604-607, 2020 05 08.
Artigo em Inglês | MEDLINE | ID: mdl-32381716

RESUMO

Molecules from symbiotic microorganisms pervasively infiltrate almost every organ system of a mammalian host, marking the initiation of microbial-host mutualism in utero, long before the newborn acquires its own microbiota. Starting from in utero development, when maternal microbial molecules can penetrate the placental barrier, we follow the different phases of adaptation through the life events of birth, lactation, and weaning, as the young mammal adapts to the microbes that colonize its body surfaces. The vulnerability of early-life mammals is mitigated by maternal detoxification and excretion mechanisms, the protective effects of maternal milk, and modulation of neonatal receptor systems. Host adaptations to microbial exposure during specific developmental windows are critical to ensure organ function for development, growth, and immunity.


Assuntos
Bactérias/metabolismo , Feto/imunologia , Feto/microbiologia , Interações entre Hospedeiro e Microrganismos/imunologia , Troca Materno-Fetal/imunologia , Microbiota , Adaptação Fisiológica/imunologia , Animais , Dieta , Feminino , Humanos , Imunidade Inata , Lactação/imunologia , Exposição Materna , Fenômenos Fisiológicos da Nutrição Materna , Camundongos , Placentação , Gravidez , Xenobióticos/toxicidade
12.
Environ Sci Pollut Res Int ; 27(23): 28679-28694, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32447734

RESUMO

Industries continuously emit xenobiotics into the environment, which increases risks of exposing humans and other biota to xenobiotics. Though various conventional and modern environmental remediation technologies are being employed, some of them are ineffective in removing xenobiotics, while others are costly and not feasible for large-scale utilization. Maize stover (MS) and rice husks (RH) are produced in abundance globally, which make them ideal and cost-effective feedstocks for large-scale biochar production for environmental remediation. Since either type of pristine MS and RH biochar may not be effective in removing some xenobiotics, the incorporation of modifiers into MS/RH biochars can help to form composite MS/RH biochar which in turn can better decontaminate water and soil. Thus, this review paper provides a comprehensive overview of the preparation, characterization, and environmental remediation using pristine and composite MS/RH biochar. Possible areas for composite MS/RH biochar applications and future perspectives of the technology in reducing xenobiotics are also proposed in this paper.


Assuntos
Oryza , Poluentes do Solo , Carvão Vegetal , Descontaminação , Solo , Água , Xenobióticos , Zea mays
13.
Chemosphere ; 253: 126753, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32464781

RESUMO

Graphene oxide (GO) is an engineered nanomaterial which was demonstrated to have outstanding capacity for adsorption of organic pollutants such as polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs), the ligands and activators of the aryl hydrocarbon receptor (AhR). Due to the partially overlapping ligand capacity of AhR and pregnane X receptor (PXR), we tested the impact of GO particles on their signalling. While reporter gene assay revealed potentiating effect of GO on ligand-activated AhR-dependent luciferase activity, there was no effect for PXR. However, inducible target genes for AhR (CYP1A1) or PXR (ABCB1) were decreased at mRNA as well as protein levels by the presence of GO in HepG2 (for AhR), LS180 (for PXR) or primary human hepatocytes (both receptors). Moreover, the presence of GO diminished PXR and AhR protein levels in primary cultures of human hepatocytes. This was partially reversed by proteasome inhibitor MG132 for AhR but not for PXR. In conclusion, GO decreases ligand-stimulated activities of AhR and PXR in human cells.


Assuntos
Grafite/química , Xenobióticos/metabolismo , Biotransformação , Citocromo P-450 CYP1A1/metabolismo , Genes Reporter , Hepatócitos/efeitos dos fármacos , Humanos , Receptor de Pregnano X , RNA Mensageiro/metabolismo , Receptores de Hidrocarboneto Arílico/metabolismo , Receptores de Esteroides/genética , Transdução de Sinais , Xenobióticos/química
14.
Food Chem Toxicol ; 141: 111418, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32437891

RESUMO

Occupational, residential, dietary and environmental exposures to mixtures of synthetic anthropogenic chemicals after World War II have a strong relationship with the increase of chronic diseases, health cost and environmental pollution. The link between environment and immunity is particularly intriguing as it is known that chemicals and drugs can cause immunotoxicity (e.g., allergies and autoimmune diseases). In this review, we emphasize the relationship between long-term exposure to xenobiotic mixtures and immune deficiency inherent to chronic diseases and epidemics/pandemics. We also address the immunotoxicologic risk of vulnerable groups, taking into account biochemical and biophysical properties of SARS-CoV-2 and its immunopathological implications. We particularly underline the common mechanisms by which xenobiotics and SARS-CoV-2 act at the cellular and molecular level. We discuss how long-term exposure to thousand chemicals in mixtures, mostly fossil fuel derivatives, exposure toparticle matters, metals, ultraviolet (UV)-B radiation, ionizing radiation and lifestyle contribute to immunodeficiency observed in the contemporary pandemic, such as COVID-19, and thus threaten global public health, human prosperity and achievements, and global economy. Finally, we propose metrics which are needed to address the diverse health effects of anthropogenic COVID-19 crisis at present and those required to prevent similar future pandemics.


Assuntos
Poluentes Atmosféricos/toxicidade , Betacoronavirus , Infecções por Coronavirus/epidemiologia , Praguicidas/toxicidade , Pneumonia Viral/epidemiologia , Xenobióticos/toxicidade , Animais , Antivirais/uso terapêutico , Infecções por Coronavirus/tratamento farmacológico , Infecções por Coronavirus/fisiopatologia , Dieta , Epidemias , Humanos , Sistema Imunitário/efeitos dos fármacos , Pandemias , Pneumonia Viral/tratamento farmacológico , Pneumonia Viral/fisiopatologia , Prevalência , Receptores de Hidrocarboneto Arílico/metabolismo , Fatores de Risco , Transdução de Sinais/efeitos dos fármacos , Tempo
15.
Pestic Biochem Physiol ; 164: 221-227, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32284130

RESUMO

τ-Fluvalinate (fluvalinate) is a highly selective pyrethroid insecticide compound used for controlling ectoparasitic mites that cause major damages in honey bee colonies. Although honey bees have resistance and low toxicity to this xenobiotic chemical, little is known about the effects of this chemical on sensory modulation and behaviors in honey bees. Here we addressed the effect on olfactory cognition at the behavioral, molecular, and neurophysiological levels. First, we found that topical application of fluvalinate to honeybee abdomen elicited somewhat severe toxicity to honey bees. Furthermore, honeybees treated with sublethal doses of fluvalinate showed a significant decrease in olfactory responses. At the molecular level, there was no change in gene expression levels of odorant receptor co-receptor (Orco), which is important for electrical conductivity induced by odorant binding in insects. Rather, small neuropeptide F (sNPF) signaling pathway was involved in olfactory fluctuation after treatment of fluvalinate. This indicates that olfactory deficits by abdominal contact of fluvalinate may stem from various internal molecular pathways in honey bees.


Assuntos
Piretrinas , Abdome , Animais , Abelhas , Nitrilos , Xenobióticos
16.
Toxicol Lett ; 328: 19-27, 2020 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-32320775

RESUMO

Oxidative stress is defined as an imbalance between the production and elimination of reactive oxygen species (ROS) are associated with various inflammation-related human disease. ROS can oxidize lipids, which subsequently undergo fragmentation to produce F2-isoprostanes (F2-IsoPs). Eight-isoprostane is one of the most extensively studied F2-IsoPs and the most commonly used biomarker for the assessment of oxidative stress in human studies. This urinary biomarker is quantified using either chemical or immunological techniques. A "physiological" range for 8-isoprostanes is needed to use this biomarker as a measure of excess oxidative stress originating from occupational exposures. However, ranges reported in the literature are inconsistent. We designed a standardized protocol of a systematic review and meta-analysis to assess baseline values for 8-isoprostane concentrations in urine of healthy adults and identify determinants of their inter- and intra-individual variability. We searched PubMed from journal inception and up to April 2019, and screened articles for studies containing F2-IsoPs concentrations in urine for healthy adult participants. We grouped studies in three biomarker groups: "8-isoprostane", "Isoprostanes" "15- F2t-Isoprostane". We computed geometric mean (GM) and geometric standard deviation (GSD) as the basis for the meta-analysis. Of the initial 1849 articles retrieved, 63 studies were included and 107 subgroups within these study populations were identified. We stratified the subgroups analyzed with the chemical methods by body mass index (BMI) reported. We provide pooled GM values for urinary 8-isoprostane concentrations in healthy adults, separately for chemical and immunological analysis in this review. The interquartile range (IQR) in subgroups with a mean BMI below 25 measured using chemical methods was 0.18 to 0.40 µg/g creatinine. We show that there is a significant positive association between BMI and urinary 8-isoprostane concentrations. We recommend adjusting urinary 8-isoprostane concentrations in spot urine with creatinine, quantifying 8-isoprostane with chemical analytical methods, and reporting results as median and quartiles. This will help in comparing results across studies.


Assuntos
Dinoprosta/análogos & derivados , Estresse Oxidativo , Adulto , Biomarcadores/urina , Dinoprosta/urina , Exposição Ambiental/análise , Humanos , Estresse Oxidativo/efeitos dos fármacos , Fumar/urina , Xenobióticos/toxicidade
17.
Bioresour Technol ; 309: 123315, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32315914

RESUMO

Japanese knotweed (JK) is considered one of the most problematic invasive plants. Great attention was paid to research any possibilities of reducing its occurrence. This work deals with possibilities of easy transformation of JK into carbon adsorbent (AC), which is usable for sorption of diclofenac and paracetamol. Activated carbons were prepared by microwave heating using H3PO4, NaOH and sodium methanolate as the chemical agents. Characterization of AC's was carried out using BET, ATR-FTIR, SEM, adsorption equilibrium and kinetics experiments. The pseudo-second-order model showed the best similarity criteria for all studied systems adsorbent/adsorbate. The sorption efficiency was influenced by the choice of activating agent, where the π-π interactions between the planes of the obtained adsorbent and the aromatic rings of adsorbate and the interactions between the adsorbate and AC functional groups of the surface played an important role. AC-H3PO4 exhibited highest adsorption capacity for both diclofenac (87.09 mg.g-1) and paracetamol (136.61 mg.g-1).


Assuntos
Carvão Vegetal , Poluentes Químicos da Água , Adsorção , Concentração de Íons de Hidrogênio , Cinética , Água , Xenobióticos
18.
Ecotoxicol Environ Saf ; 197: 110587, 2020 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-32325327

RESUMO

The persistence and bioaccumulation of environmental pollutants in water bodies, soils and living tissues remain alarmingly related to environmental protection and ecosystem restoration. Adsorption-based techniques appear highly competent in sequestering several environmental pollutants. In this review, the recent research findings reported on the assessments of composts and compost-amended soils as adsorbents of heavy metal ions, dye molecules and xenobiotics have been appraised. This review demonstrates clearly the high adsorption capacities of composts for umpteen environmental pollutants at the lab-scale. The main inferences from this review are that utilization of composts for the removal of heavy metal ions, dye molecules and xenobiotics from aqueous environments and soils is particularly worthwhile and efficient at the laboratory scale, and the adsorption behaviors and effectiveness of compost-type adsorbents for agrochemicals (e.g. herbicides and insecticides) vary considerably because of variabilities in structure, topology, bond connectivity, distribution of functional groups and interactions of xenobiotics with the active humic substances in composts. Compost-based field-scale remediation of environmental pollutants is still sparse and arguably much challenging to implement if, furthermore, real-world soil and water contamination issues are to be addressed effectively. Hence, significant research and process development efforts should be promptly geared and intensified in this direction by extrapolating the lab-scale findings in a cost-effective manner.


Assuntos
Corantes/química , Compostagem , Poluentes Ambientais/química , Metais Pesados/química , Xenobióticos/química , Adsorção , Agroquímicos/química , Recuperação e Remediação Ambiental , Substâncias Húmicas
19.
J Appl Microbiol ; 129(2): 319-334, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32118335

RESUMO

AIMS: This research was conducted to investigate the biocatalytic remediation of xenobiotics polluted seawater using two biocatalysts; whole bacterial cells of facultative aerobic halotolerant Corynebacterium variabilis Sh42 and its extracted crude enzymes. METHODS AND RESULTS: One-Factor-at-A-Time technique and statistical analysis were applied to study the effect of initial substrate concentrations, pH, temperature, and initial biocatalyst concentrations on the batch biocatalytic degradation of three xenobiotic pollutants (2-hydroxybiphenyl (2-HBP), catechol and benzoic acid) in artificial seawater (salinity 3·1%). HPLC and gas-chromatography mass spectroscopy analyses were utilized to illustrate the quantitative removal of the studied aromatic xenobiotic pollutants and their catabolic pathway. The results revealed that the microbial and enzymatic cultures followed substrate inhibition kinetics. Yano and Koga's equation showed the best fit for the biokinetic degradation rates of 2-HBP and benzoic acid, whereas Haldane biokinetic model adequately expressed the specific biodegradation rate of catechol. The biokinetic results indicated the good efficiency and tolerance of crude enzyme for biocatalytic degradation of extremely high concentrations of aromatic pollutants than whole C. variabilis Sh42 cells. The monitored by-products indicated that the catabolic degradation pathway followed an oxidation mechanism via a site-specific monooxygenase enzyme. Benzoic acid and catechol were identified as major intermediates in the biodegradation pathway of 2-HBP, which were then biodegraded through meta-cleavage to 2-hydroxymuconic semialdehyde. With time elapsed, the semialdehyde product was further biodegraded to acetaldehyde and pyruvic acid, which would be further metabolized via the bacterial TCA cycle. CONCLUSION: The batch enzymatic bioreactors performed superior-specific biocatalytic degradation rates for all the studied xenobiotic pollutants. SIGNIFICANCE AND IMPACT OF THE STUDY: The enzymatic system of C. variabilis Sh42 is tolerable for toxic xenobiotics and different physicochemical environmental parameters. Thus, it can be recommended as an effective biocatalyst for biocatalytic remediation of xenobiotics polluted seawater.


Assuntos
Água do Mar/química , Poluentes Químicos da Água/metabolismo , Xenobióticos/metabolismo , Biocatálise , Biodegradação Ambiental , Reatores Biológicos , Corynebacterium/metabolismo , Cinética , Redes e Vias Metabólicas
20.
PLoS One ; 15(2): e0228623, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32084152

RESUMO

Hepatopancreatic necrosis disease (HPND) is a newly emerging disease in the Chinese mitten crab, Eriocheir sinensis, which has resulted in large economic losses. However, the underlying cause of this disease remains unclear. To better understand the pathogenesis and pathogenic mechanism of HPND, we compared the transcriptome differences of the hepatopancreas of E. sinensis with and without HPND. The analysis yielded > 30 million reads for each sample of three test (with HPND) and three control groups (without HPND). We observed 978 downregulated genes and 644 upregulated genes. Among the gene ontology categories "biological process," "cellular component," and "molecular function", the subcategories cellular process, single-organism process, biological regulation, metabolic process, cell part, organelle, organelle part, binding, and catalytic were enriched. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis showed that "metabolism of xenobiotics by cytochrome P450," "drug metabolism-cytochrome P450," "chemical carcinogenesis," and "material metabolism" were the "five" most significantly enriched pathways in the hepatopancreas of E. sinensis with HPND. The results revealed that material metabolic abnormalities and drug effects from the external environment might be associated with HPND in the Chinese mitten crab. Considering the wide use of pyrethroids for pond cleaning in Xinghua city, we speculated that pyrethroids might cause HPND in the Chinese mitten crab. Our study provided useful information about the cause and pathogenetic mechanisms of HPND and could help to prevent this disease in production practice.


Assuntos
Braquiúros/genética , Hepatopâncreas/metabolismo , Transcriptoma , Animais , Braquiúros/metabolismo , Sistema Enzimático do Citocromo P-450/genética , Sistema Enzimático do Citocromo P-450/metabolismo , Hepatopâncreas/efeitos dos fármacos , Hepatopâncreas/patologia , Necrose , Xenobióticos/metabolismo , Xenobióticos/toxicidade
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