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2.
Rev Med Liege ; 76(2): 105-110, 2021 Feb.
Artículo en Francés | MEDLINE | ID: mdl-33543856

RESUMEN

Endocrine disruptors are chemicals or natural molecules able to interfere with the hormonal system of living organisms. These pollutants can promote the emergence of diseases of the endocrine system in humans or animals. In this publication, we will focus on certain families of endocrine disrupting chemicals that may contribute to the development of type 2 diabetes, a disease whose prevalence is increasing strongly in the world.


Asunto(s)
Diabetes Mellitus Tipo 2 , Disruptores Endocrinos , Contaminantes Ambientales , Animales , Diabetes Mellitus Tipo 2/inducido químicamente , Diabetes Mellitus Tipo 2/epidemiología , Disruptores Endocrinos/toxicidad , Sistema Endocrino , Contaminantes Ambientales/toxicidad , Humanos
3.
Adv Exp Med Biol ; 1300: 205-229, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33523436

RESUMEN

Environmental endocrine-disrupting chemicals (EDCs) are xenobiotic compounds that are frequently contacted in daily life. With the species and quantity of substances created and utilized by human beings significantly surpassing the self-purification capacity of nature, a large number of hazardous substances are enriched in the human body through the respiratory tract, digestive tract, and skin. Some of these compounds cause many problems endangering female reproductive health by simulating/antagonizing endogenous hormones or affecting the synthesis, metabolism, and bioavailability of endogenous hormones, including reproductive disorders, fetal birth defects, fetal developmental abnormalities, endocrine and metabolic disorders, and even gynecological malignancies. Therefore, the study of the relationship between environmental EDCs and female reproductive diseases and related mechanisms is of considerable significance to women, children health care, and improve the quality of the population.


Asunto(s)
Disruptores Endocrinos , Contaminantes Ambientales , Niño , Disruptores Endocrinos/toxicidad , Sistema Endocrino , Exposición a Riesgos Ambientales/efectos adversos , Contaminantes Ambientales/toxicidad , Femenino , Hormonas/farmacología , Humanos , Reproducción , Salud Reproductiva
4.
Toxicol Lett ; 340: 43-51, 2021 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-33440227

RESUMEN

In France, part of the population is overexposed to cadmium by the diet. In our work, we first revised the tolerable daily intake (TDI) of 0.36 µg Cd.kg bw.d.-1 proposed by the European Food Safety Authority (EFSA), derived from effects on kidneys and based on the critical urinary Cd concentration of 1.0 µg Cd.g-1 creatinine for humans. After reviewing the epidemiological data on Cd toxicity published after 2011, bone effects were selected as the critical effects. Body burden data of 0.5 µg.g-1 creatinine was chosen for the critical threshold for human urinary cadmium concentrations. To be used for the derivation of the new oral toxicological reference value, we used a modified physiologically based pharmacokinetic model (PBPK). The reverse calculation on the PBPK model gave a TDI of 0.35 µg Cd.kg bw-1.day-1. This TDI is compatible with a urinary Cd concentrations not exceeding 0.5 µg Cd.g-1 creatinine, in a 60 year-old adult, assuming that ingestion is the only source of exposure to Cd at 60 years. After implementing the PBPK model with French physiological data, Cd biological reference values as a function of age were modelled so as to remain below the revised health-based guidance values.


Asunto(s)
Cadmio/toxicidad , Exposición a Riesgos Ambientales/estadística & datos numéricos , Contaminantes Ambientales/administración & dosificación , Contaminantes Ambientales/toxicidad , Carga Corporal (Radioterapia) , Dieta , Contaminación de Alimentos , Inocuidad de los Alimentos , Francia , Humanos , Medición de Riesgo
5.
Ecotoxicol Environ Saf ; 208: 111610, 2021 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-33396130

RESUMEN

Hepatic oxidative stress, as one important mechanism of cadmium (Cd)-induced hepatic toxicity, could, as known, be ameliorated by vitamin E (VE). However, the underlying mechanism remains to be elucidated. To investigate whether the antioxidant vitamin E can protect against Cd-induced sub-chronic liver injury associated with oxidative stress and nuclear factor erythrocyte 2-related factor 2 (Nrf2) pathway, male Sprague-Dawley rats (nine-week-old) were randomly divided into four groups (eight rats/group), namely, control, VE (100 mg/kg VE), Cd (5 mg/kg CdCl2) and VE+Cd (100 mg/kg VE+5 mg/kg CdCl2), and received intragastric administration of Cd and/or VE for four weeks. Cd-exposure alone resulted in reduced liver weight, liver histological alteration and oxidative stress, accumulation of Cd in the liver, elevated ALT and AST concentrations in serum together with decreased mRNA and protein expressions of Nrf2 pathway related molecules (Nrf2, HO-1, NQO-1, GCLC, GCLM and GST). However, the co-treatment of Cd and VE significantly ameliorated the changes mentioned above, and promoted the expression of genes and proteins of Nrf2 pathway related molecules in comparison to the Cd-exposure alone. Our results indicate that the protective effect of VE against Cd-induced sub-chronic hepatic damage in rats is associated with the inhibition of oxidative stress and activation of Nrf2 pathway.


Asunto(s)
Antioxidantes/farmacología , Cadmio/toxicidad , Enfermedad Hepática Inducida por Sustancias y Drogas/prevención & control , Contaminantes Ambientales/toxicidad , Factor 2 Relacionado con NF-E2/metabolismo , Estrés Oxidativo/efectos de los fármacos , Vitamina E/farmacología , Animales , Antioxidantes/metabolismo , Enfermedad Hepática Inducida por Sustancias y Drogas/metabolismo , Enfermedad Hepática Inducida por Sustancias y Drogas/patología , Hígado/efectos de los fármacos , Hígado/metabolismo , Hígado/patología , Pruebas de Función Hepática , Masculino , Tamaño de los Órganos/efectos de los fármacos , Ratas , Ratas Sprague-Dawley , Transducción de Señal
6.
Ecotoxicol Environ Saf ; 208: 111697, 2021 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-33396028

RESUMEN

Owing to the unique properties and useful applications in numerous fields, nanomaterials (NMs) received a great attention. The mass production of NMs has raised major concern for the environment. Recently, some altered growth patterns in plants have been reported due to the plant-NMs interactions. However, for NMs safe applications in agriculture and medicine, a comprehensive understanding of bio-nano interactions is crucial. The main goal of this review article is to summarize the results of the toxicological studies that have shown the in vitro and in vivo interactions of NMs with plants. The toxicity mechanisms are briefly discussed in plants as the defense mechanism works to overcome the stress caused by NMs implications. Indeed, the impact of NMs on plants varies significantly with many factors including physicochemical properties of NMs, culture media, and plant species. To investigate the impacts, dose metrics is an important analysis for assaying toxicity and is discussed in the present article to broadly open up different aspects of nanotoxicological investigations. To access reliable quantification and measurement in laboratories, standardized methodologies are crucial for precise dose delivery of NMs to plants during exposure. Altogether, the information is significant to researchers to describe restrictions and future perspectives.


Asunto(s)
Ecotoxicología/normas , Contaminantes Ambientales/toxicidad , Nanoestructuras/toxicidad , Plantas/efectos de los fármacos , Agricultura , Ecotoxicología/tendencias , Contaminantes Ambientales/química , Humanos , Nanoestructuras/química , Desarrollo de la Planta/efectos de los fármacos , Plantas/clasificación , Plantas/metabolismo , Especificidad de la Especie , Estrés Fisiológico/efectos de los fármacos
7.
Ecotoxicol Environ Saf ; 208: 111699, 2021 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-33396030

RESUMEN

Extensive industrial activities have led to an increase of the content of chromium in the environment, which causes serious pollution to the surrounding water, soil and atmosphere. The enrichment of chromium in the environment through the food chain ultimately affects human health. Therefore, the remediation of chromium pollution is crucial to development of human society. A lot of scholars have paid attention to bioremediation technology owing to its environmentally friendly and low-cost. Previous reviews mostly involved pure culture of microorganisms and rarely discussed the optimization of bioreduction conditions. To make up for these shortcomings, we not only introduced in detail the conditions that affect microbial reduction but also innovatively introduced consortium which may be the cornerstone for future treatment of complex field environments. The aim of this study is to summary chromium toxicity, factors affecting microbial remediation, and methods for enhancing bioremediation. However, the actual application of bioremediation technology is still facing a major challenge. This study also put forward the current research problems and proposed future research directions, providing theoretical guidance and scientific basis for the application of bioremediation technology.


Asunto(s)
Biodegradación Ambiental , Cromo/aislamiento & purificación , Contaminantes Ambientales/aislamiento & purificación , Cromo/metabolismo , Cromo/toxicidad , Contaminantes Ambientales/metabolismo , Contaminantes Ambientales/toxicidad , Humanos , Consorcios Microbianos/fisiología
8.
Ecotoxicol Environ Saf ; 208: 111611, 2021 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-33396131

RESUMEN

Fluoride is a widespread environmental pollutant that at high levels exerts numerous deleterious effects on human health. The toxic effects of fluoride are a matter of serious concern since many countries have regions of endemic fluorosis. The main source of fluoride exposure for humans is intake of contaminated groundwater. Fluoride is absorbed from the gastrointestinal tract and enters the circulating blood, where the abundant red blood cells (RBC) are an early and major target of fluoride toxicity. Chronic fluoride exposure generates free radicals, reactive species which leads to redox imbalance, cytotoxicity and hematological damage. This study aimed to determine the effect of sodium fluoride (NaF) on human RBC under in vitro conditions. Isolated RBC were incubated with different concentrations of NaF (10-500 µM) for 8 h at 37 °C. Several biochemical parameters were determined in hemolysates or whole cells. Treatment of RBC with NaF enhanced the generation of reactive oxygen and nitrogen species. This increased the oxidation of hemoglobin to yield methemoglobin and oxoferrylhemoglobin, which are inactive in oxygen transport. NaF treatment increased the degradation of heme causing release of free iron from its porphyrin ring. Cellular antioxidant power was significantly decreased in NaF-treated RBC, lowering the metal reducing and free radical quenching ability of cells. The two pathways of glucose metabolism in RBC i.e. glycolysis and hexose monophosphate shunt, were inhibited. NaF also inhibited the plasma membrane redox system, and its associated ascorbate free radical reductase, to disrupt transmembrane electron transport. These results suggest that fluoride generates reactive species that cause extensive oxidative modifications in human RBC.


Asunto(s)
Antioxidantes/metabolismo , Contaminantes Ambientales/toxicidad , Eritrocitos/efectos de los fármacos , Hemoglobinas/metabolismo , Potenciales de la Membrana/efectos de los fármacos , Especies de Nitrógeno Reactivo/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Fluoruro de Sodio/toxicidad , Adulto , Células Cultivadas , Transporte de Electrón , Recuento de Eritrocitos , Eritrocitos/metabolismo , Humanos , Hierro/metabolismo , Oxidación-Reducción , Estrés Oxidativo/efectos de los fármacos , Oxidorreductasas/metabolismo
9.
Ecotoxicol Environ Saf ; 208: 111564, 2021 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-33396094

RESUMEN

Ammonia (NH3) is a major pollutant in livestock houses and atmospheric environment. It has been demonstrated that NH3 can cause a series of damage to animals and human. However, toxicity evaluation of NH3 on farm animals was rarely reported, especially in the intestinal microflora. Therefore, in this study, twenty-four 125-day-old fattening pigs were randomly divided into 4 groups: control group, NH3 group (88.2 mg m-3 < NH3 concentration < 90.4 mg m-3), Se group (Se content: 0.5 mg kg-1), and NH3 + Se group (88.2 mg m-3 < NH3 concentration < 90.4 mg m-3, Se content: 0.5 mg kg-1), and the effects of NH3 and L-Selenomethionine on the microbiota composition in the jejunum and the levels of inflammatory markers in feces of fattening pigs were examined by 16S rDNA and ELISA, respectively. Our results showed that the content of Matrix metalloproteinase-9 (MMP-9), Myeloperoxidase (MPO), Lactoferrin (LTF) and Calprotectin in the ammonia group (A group) were significantly elevated compared to the control group, and the content of MMP-9, MPO, LTF and Calprotectin in the A + Se group were significantly reduced. A significant difference in microbiota composition in the phylum, class, family and genus levels was found in the A group and the NH3 + Se group. There was a negative correlation between Streptococcus and Calprotectin. Our results indicated that excessive NH3 inhalation could cause changes in inflammatory markers and beta diversity of intestinal microflora in fattening pigs. We found there was a positive correlation between MPO and Pseudomonas. In addition, we first proposed that L-Selenomethionine could improve the imbalance of microbial flora and the inflammatory injury caused by NH3. Changes in intestinal microflora and inflammatory markers can be used as important indicators to evaluate NH3 toxicity, and studying changes in intestinal microflora is also an important mechanism to reveal NH3 toxicity.


Asunto(s)
Amoníaco/toxicidad , Contaminantes Ambientales/toxicidad , Microbioma Gastrointestinal/efectos de los fármacos , Animales , Antioxidantes , Biomarcadores , Inflamación/genética , Porcinos
10.
Ecotoxicol Environ Saf ; 208: 111570, 2021 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-33396099

RESUMEN

Traditional brominated flame retardants (BFRs) negatively affect the environment and human health, especially in the sensitive (developing) nervous system. Considering the physicochemical similarities between novel brominated flame retardants (NBFRs) and BFRs, more and more evidence reveals the neurotoxic effects of NBFRs. We reviewed the neuro(endocrine) toxic effects of NBFRs in vivo and in vitro and discussed their action mechanisms based on the available information. The neurotoxic potential of NBFRs has been demonstrated through direct neurotoxicity and disruption of the neuroendocrine system, with adverse effects on neurobehavioral and reproductive development. Mechanistic studies have shown that the impact of NBFRs is related to the complex interaction of neural and endocrine signals. From disrupting the gender differentiation of the brain, altering serum thyroid/sex hormone levels, gene/protein expression, and so on, to interfere with the feedback effect between different levels of the HPG/HPT axis. In this paper, the mechanism of neurotoxic effects of NBFRs is explored from a new perspective-neuro and endocrine interactions. Gaps in the toxicity data of NBFRs in the neuroendocrine system are supplemented and provide a broader dataset for a complete risk assessment.


Asunto(s)
Sistema Endocrino/efectos de los fármacos , Contaminantes Ambientales/toxicidad , Retardadores de Llama/toxicidad , Monitoreo del Ambiente , Éteres Difenilos Halogenados/análisis , Humanos , Hidrocarburos Bromados/análisis , Síndromes de Neurotoxicidad/metabolismo , Medición de Riesgo , Hormonas Tiroideas
11.
Ecotoxicol Environ Saf ; 208: 111581, 2021 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-33396104

RESUMEN

Lead (Pb) stress affects hormone-mediated responses (e.g., reproduction) in insects. In this study, the effects of Pb stress (12.5-50 mg Pb/kg in larval artificial diets) on the reproduction of the common cutworm Spodoptera litura (Lepidoptera: Noctuidae) were investigated after 7 generations. The results showed that Pb stress did not reduce the longevity of adult females, but 50 mg Pb/kg significantly reduced the longevity of adult males, regardless of the generation. After 50 mg Pb/kg stress for one or 7 generations, the peak time of egg-laying was delayed, and egg production and hatchability were decreased significantly. The vitellin content in eggs was significantly inhibited by Pb stress. The S. litura vitellogenin (Vg) gene promoter was cloned and analyzed. Multiple putative transcription factors were predicted for the 2321 bp Vg promoter region, including the TATA box, GATA, basic helix-loop-helix (bHLH) transcription factor, Broad-Complex (BR-C) binding sites, etc. The fragment from -2222 to -211 bp of the Vg promoter was the activation domain for Vg, whereas the region from -211 to -55 bp repressed the activity of the Vg promoter. The construct promoter (-782/+76) in Trichoplusia ni (Hi5) cells significantly improved Vg expression, which was not affected by Pb stress (1 or 10 mg/ml). Therefore, Pb stress significantly inhibited the reproduction of S. litura but not by regulating the Vg promoter.


Asunto(s)
Contaminantes Ambientales/toxicidad , Plomo/toxicidad , Spodoptera/fisiología , Vitelogeninas/genética , Animales , Dieta , Contaminantes Ambientales/metabolismo , Femenino , Larva/efectos de los fármacos , Plomo/metabolismo , Longevidad , Masculino , Mariposas Nocturnas , Oviposición/efectos de los fármacos , Reproducción/efectos de los fármacos , Spodoptera/efectos de los fármacos , Vitelogeninas/metabolismo
12.
Ecotoxicol Environ Saf ; 208: 111625, 2021 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-33396145

RESUMEN

Data for US adults aged ≥20 years from National Health and Nutrition Examination Survey for the years 2003-2014 were analyzed to evaluate how adjusted (N = 8481) and unadjusted (N = 9080) levels of selected perfluoroalkyl acids (PFAA) vary across the different stages of glomerular function (GF) among those who did not have diabetes, anemia, or albuminuria as compared to those who had diabetes only, anemia only, and albuminuria only. PFAAs selected for analyses were: perfluorooctanoic acid (PFOA), perfluorooctane sulfonic acid (PFOS), perfluorodecanoic acid (PFDA), perfluorohexane sulfonic acid (PFHxS), and perfluorononanoic acid (PFNA). Irrespective of GF stage, there was no noticeable evidence to suggest that adjusted levels of PFAA for those with diabetes only are any lower than those with no diabetes, no anemia, and no albuminuria. Those who had anemia only were found to have lower adjusted levels of at least PFOA, PFOS, PFDA, and PFHxS than those who had no diabetes, no anemia, and no albuminuria. These results were seen in the presence (eGFR < 60 mL/min/1.73 m2) as well as the absence of chronic kidney disease. For GF-1 (eGFR > 90 mL/min/1.73 m2), GF-2 (60 ≤ eGFR ≤ 90 mL/min/1.73 m2), and GF-3B/4 (15 < eGFR ≤ 45 mL/min/1.73 m2), those who had albuminuria only had lower adjusted levels of PFOA, PFOS, and PFHxS than those who had no diabetes, no anemia, and no albuminuria. In general, adjusted levels of those who had albuminuria only were lower than those who had anemia only at GF-3 and more often than not at GF-1 and GF-2. Rise in adjusted levels of PFAA from GF-1 to GF-3A (45 < eGFR < 60 mL/min/1.73 m2) was faster for those with anemia only than any other comparison group for the total population and females.


Asunto(s)
Exposición a Riesgos Ambientales/estadística & datos numéricos , Contaminantes Ambientales/toxicidad , Fluorocarburos/toxicidad , Riñón/fisiología , Adulto , Albuminuria/epidemiología , Ácidos Alcanesulfónicos/toxicidad , Anemia/epidemiología , Biomarcadores/metabolismo , Caprilatos/toxicidad , Ácidos Decanoicos/toxicidad , Diabetes Mellitus/epidemiología , Femenino , Humanos , Riñón/efectos de los fármacos , Masculino , Persona de Mediana Edad , Encuestas Nutricionales , Ácidos Sulfónicos
13.
Ecotoxicol Environ Saf ; 208: 111683, 2021 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-33396015

RESUMEN

The possibility of detecting the damaging effect of cadmium salts on red blood cells (RBC) membrane by atomic force microscopy and light microscopy was studied. White wistar rats RBC were incubated with cadmium chloride in concentrations of 1 µg/l, 10 µg/l, 100 µg/l, and 1000 µg/l for the research. A comparison of sample preparation methods proposed by other authors in previous studies is made. The optimal method that does not significantly affect the change in the morphological features of the cell is selected. The quantitative assessment of damaged and destroyed RBC depending on the concentration of cadmium was performed by optical microscopy. The study showed that CdCl2 has a damaging effect on the RBC membrane, which leads to the formation of non-specific cell forms. A comparative assessment was made between the methods of optical microscopy and atomic force microscopy for the suitability of studying the morphological characteristics of abnormal forms of the RBC. It is shown that the method of atomic force microscopy allows registering morphological changes in the RBC that cannot be registered by optical microscopy. It is pointed that CdCl2 has effect on destruction of the RBC and the formation of specific bulges on the RBC membrane. Influence of CdCl2 on the RBC mechanical properties was studied using atomic force microscopy. The possibility of using atomic force microscopy in studies of morphology and mechanical properties of the RBC under toxicity effect of cadmium is shown.


Asunto(s)
Cloruro de Cadmio/toxicidad , Contaminantes Ambientales/toxicidad , Membrana Eritrocítica/efectos de los fármacos , Eritrocitos/efectos de los fármacos , Microscopía de Fuerza Atómica/métodos , Animales , Relación Dosis-Respuesta a Droga , Membrana Eritrocítica/patología , Eritrocitos/citología , Eritrocitos/metabolismo , Humanos , Metalotioneína/metabolismo , Ratas , Ratas Wistar , Especies Reactivas de Oxígeno/metabolismo
14.
Ecotoxicol Environ Saf ; 208: 111686, 2021 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-33396018

RESUMEN

Human exposure to mercury is a major public health concern, causing neurological outcomes such as motor and visual impairment and learning disabilities. Currently, human exposure in the Amazon is among the highest in the world. A recent systematic review (doi:10.1016/j.jtemb.2018.12.001), however, highlighted the lack of high-quality studies on mercury-associated neurotoxicity. There is, therefore, a need to improve research and much to still learn about how exposure correlates with disease. In this review, we discuss studies evaluating the associations between neurological disturbances and mercury body burden in Amazonian populations, to generate recommendations for future studies. A systematic search was performed during July 2020, in Pubmed/Medline, SCOPUS and SCIELO databases with the terms (mercury*) and (Amazon*). Four inclusion criteria were used: original article (1), with Amazonian populations (2), quantifying exposure (mercury levels) (3), and evaluating neurological outcomes (4). The extracted data included characteristics (as year or origin of authorship) and details of the research (as locations and type of participants or mercury levels and neurological assessments). Thirty-four studies, most concentrated within three main river basins (Tapajós, Tocantins, and Madeira) and related to environmental exposure, were found. Mercury body burden was two to ten times higher than recommended and main neurological findings were cognitive, vision, motor, somatosensory and emotional deficits. Important insights are described that support novel approaches to researching mercury exposure and intoxication, as well as prevention and intervention strategies. As a signatory country to the Minamata Convention, Brazil has the opportunity to play a central role in improving human health and leading the research on mercury intoxication.


Asunto(s)
Exposición a Riesgos Ambientales/efectos adversos , Contaminantes Ambientales/toxicidad , Intoxicación del Sistema Nervioso por Mercurio/etiología , Mercurio/toxicidad , Ríos/química , Carga Corporal (Radioterapia) , Brasil , Exposición a Riesgos Ambientales/análisis , Contaminantes Ambientales/análisis , Femenino , Cabello/química , Humanos , Masculino , Mercurio/análisis , Intoxicación del Sistema Nervioso por Mercurio/epidemiología , Intoxicación del Sistema Nervioso por Mercurio/metabolismo
15.
Ecotoxicol Environ Saf ; 208: 111687, 2021 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-33396019

RESUMEN

Manganese (Mn) is demonstrated to be essential for plants. Ion homeostasis is maintained in plant cells by specialized transporters. PbMTP8.1, which encodes a putative Mn-CDF transporter in Pyrus bretschneideri Rehd, was expressed mainly in leaves and complemented the Mn hypersensitivity of the Mn-sensitive yeast mutant △pmr1 in previous research conducted by our laboratory. In the present study, we report that the expression of PbMTP8.1 can enhance Mn tolerance and accumulation in Saccharomyces cerevisiae. Subcellular localization analysis of the PbMTP8.1-GFP fusion protein indicated that PbMTP8.1 was targeted to the pre-vacuolar compartment (PVC). In addition, the overexpression of PbMTP8.1 in Arabidopsis thaliana conferred increased resistance to plants under toxic Mn levels, as indicated by increased fresh and dry weights of shoots and roots. Mn accumulation in vacuoles of PbMTP8.1-overexpressing plants was significantly increased when compared with that in wild-type plants under Mn stress. This suggests that a considerable proportion of Mn enters into the vacuoles through a PbMTP8.1-dependent mechanism. Taken together, these results indicate PbMTP8.1 is a Mn-specific transporter that is localized to the PVC, and confers Mn tolerance by sequestering Mn into the vacuole.


Asunto(s)
Arabidopsis/metabolismo , Proteínas de Transporte de Catión/genética , Contaminantes Ambientales/toxicidad , Manganeso/toxicidad , Pyrus/metabolismo , Saccharomyces cerevisiae/metabolismo , Adaptación Biológica/genética , Arabidopsis/genética , Contaminantes Ambientales/metabolismo , Manganeso/metabolismo , Células Vegetales/metabolismo , Hojas de la Planta/genética , Hojas de la Planta/metabolismo , Raíces de Plantas/genética , Raíces de Plantas/metabolismo , Pyrus/genética , Saccharomyces cerevisiae/genética , Vacuolas/metabolismo
16.
Ecotoxicol Environ Saf ; 210: 111850, 2021 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-33421715

RESUMEN

Lead (Pb) is a pervasive global contaminant that interferes with sensitive windows for neurological development and causes oxidative damage to tissues. The effects of moderate and high exposure to Pb have been well-studied in birds, but whether low-level early-life exposure to Pb influences adult phenotype remains unclear. Female songbirds use a male's song and coloration to discriminate between high- and low-quality males. Therefore, if early-life exposure to Pb disrupts song learning ability or shifts the allocation of antioxidant pigments away from colorful secondary sexual traits, male birds exposed to Pb may be less attractive to females. We exposed developing zebra finches (Taeniopygia guttata) to Pb-contaminated drinking water (100 or 1000 parts per billion [ppb]) after hatching (days 0-100). Once male finches reached adulthood (120-150 days post hatch), we measured song learning ability, coloration of bill and cheek patches, and volume of song nuclei in the brain. We also measured female preference for Pb-exposed males relative to control males. Finally, we measured motoric and spatial cognitive performance in male and female finches to assess whether cognitive traits differed in their sensitivity to Pb exposure. Male zebra finches exposed to 1000 ppb Pb had impaired song learning ability, reduced volume of song nuclei, bills with less redness and received less attention from females. Additionally, Pb exposure impaired motoric performance in both male and female finches but did not affect performance in a spatial cognitive task. Adult finches exposed to Pb-contaminated water had higher blood-Pb levels, though in all cases blood-Pb levels were below 7.0 µg dL-1. This study suggests that low-level exposure to Pb contributes to cognitive deficits that persist into adulthood and may indirectly influence fitness by altering secondary sexual traits and reducing male attractiveness.


Asunto(s)
Contaminantes Ambientales/toxicidad , Pinzones/fisiología , Plomo/toxicidad , Animales , Atención , Cognición/efectos de los fármacos , Femenino , Aprendizaje/efectos de los fármacos , Masculino , Fenotipo , Pigmentación/efectos de los fármacos , Vocalización Animal/efectos de los fármacos
17.
Ecotoxicol Environ Saf ; 208: 111637, 2021 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-33396157

RESUMEN

Polycyclic Aromatic Hydrocarbons (PAH) are a class of organic pollutants normally found as mixtures with effects often hard to predict, which poses a major challenge for risk assessment. In this study, we address the effects of Phenanthrene (Phe), benzo[b]fluoranthene (B[b]F) and their mixtures (2 Phe:1 B[b]F; 1 Phe: 1 B[b]F; 1 Phe: 2 B[b]F) over glutathione (GSH) synthesis and function in HepG2 cells. We analyzed the effects on cellular viability, ROS production, glutathione (GSH) levels, protein-S-glutathionylation (PSSG), the activity of glutathione peroxidase (GPx), glutathione-S-transferases (GST) and glutathione reductase (GR). Transcript (mRNA) levels of glutathione synthesis enzymes - glutathione cysteine ligase catalytical (GCLC) and modifying (GCLM) sub-units and glutathione synthetase (GS) - and Nrf2 translocation to the nucleus were analyzed. Phe showed a higher cytotoxicity (IC50 = 130 µM after 24 h) than B[b]F related to a higher ROS production (up-to 50% for Phe). In agreement, GSH levels were significantly increased (up-to 3-fold) by B[b]F and were accompanied by an increase in the levels of PSSG, which is a mechanism that protect proteins from oxidative damage. The upregulation of GSH was the consequence of Nrf2 signaling activation and increased levels of GCLC, GCLM and GS mRNA observed after exposure to B[b]F, but not during exposure to Phe. Most interestingly, all mixtures showed higher cytotoxicity than individual compounds, but intriguingly it was the 1 Phe: 1B[b]F mixture showing the highest cytotoxicity and ROS production. GSH levels were not significantly upregulated not even in the mixture enriched in B[b]F. These results point to the role of GSH as a central modulator of PAH toxicity and demonstrate the idiosyncratic behavior of PAH mixtures even when considering only two compounds in varying ratios.


Asunto(s)
Contaminantes Ambientales/toxicidad , Fluorenos/toxicidad , Glutatión/biosíntesis , Hepatocitos/efectos de los fármacos , Fenantrenos/toxicidad , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Hepatocitos/metabolismo , Humanos , Estrés Oxidativo/efectos de los fármacos , Hidrocarburos Policíclicos Aromáticos/toxicidad
18.
Ecotoxicol Environ Saf ; 208: 111638, 2021 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-33396158

RESUMEN

The flame retardant decabrominated diphenyl ether (BDE-209) is a widely used chemical in a variety of products and exists extensively in the environment. BDE-209 has been reported to induce kidney injury and dysfunction. However, the causes and mechanisms of its nephrotoxicity are still under investigation. In this study, 150 male broilers were exposed to BDE-209 concentrations of 0, 0.004, 0.04, 0.4, 4.0 g/kg for 42 days. The relative kidney weight, histopathology, markers of renal injury, oxidative stress, inflammation, apoptosis and the expression of MAPK signaling pathways-related proteins were assessed. The results showed that the concentrations of blood urea nitrogen (BUN), creatinine (CRE) and the neutrophil gelatinase-associated lipocalin (NGAL), significantly increased after exposure to BDE-209 with the doses more than 0.04 g/kg. Similarly, severe damage of renal morphology was observed, including atrophy and necrosis of glomeruli, and swelling and granular degeneration of the renal tubular epithelium. In the renal homogenates, the oxidative stress was evidenced by the elevated concentrations of MDA and NO, and decreased levels of GSH-Px, GSH and SOD. Due to the inflammatory response, the level of NF-κB and the pro-inflammatory cytokines TNF-α, IL-1ß, IL-18 were remarkably upregulated, while the content of the anti-inflammatory cytokine IL-10 decreased. Additionally, the apoptotic analysis showed notable upregulations of Bax/Bcl-2 ratio, the relative expression of p-ERK1/2 and p-JNK1/2, and the expression of Bax, cytochrome c and caspase 3. The present study indicates that BDE-209 exposure can cause nephrotoxicity in broilers through oxidative stress and inflammation, which activate the phosphorylation of key proteins of the MAPK signaling pathways, and subsequently induce mitochondria-mediated kidney apoptosis.


Asunto(s)
Lesión Renal Aguda/inducido químicamente , Contaminantes Ambientales/toxicidad , Retardadores de Llama/toxicidad , Éteres Difenilos Halogenados/toxicidad , Lesión Renal Aguda/metabolismo , Lesión Renal Aguda/patología , Animales , Apoptosis/efectos de los fármacos , Pollos , Inflamación/inducido químicamente , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Masculino , Estrés Oxidativo/efectos de los fármacos
19.
Ecotoxicol Environ Saf ; 211: 111938, 2021 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-33476844

RESUMEN

Melamine cyanuric acid (MCA) is a flame retardant linked by hydrogen bonds between melamine and cyanuric acid. MCA is used in an excellent series of phosphorus and nitrogen flame retardants. MCA can harm the kidney, liver, testis, and spleen cells. However, the effects of MCA on the emotions and behaviour of adolescent mice have not yet been investigated. In this article, male mice were exposed to MCA at 10, 20, and 40 mg/kg for four weeks. MCA exposure resulted in enhanced mouse locomotor and nocturnal activity. We also observed anxiety-like and depression-like behaviours. Moreover, after MCA exposure, the serum concentrations of thyroid-related hormones were changed, and the mRNA levels were affected. In short, MCA exposure can cause behavioural and emotion disorders.


Asunto(s)
Conducta Animal/efectos de los fármacos , Contaminantes Ambientales/toxicidad , Triazinas/toxicidad , Animales , Retardadores de Llama , Riñón , Masculino , Ratones , Bazo , Testículo
20.
Ecotoxicol Environ Saf ; 211: 111919, 2021 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-33476853

RESUMEN

The aim of this study was to elucidate the effect of pH on bacterial resistance mechanisms to copper (Cu) stress by genomic and transcriptomic analysis. Klebsiella michiganensis cells were exposed to 0.5 mM CuCl2 at pH 4 and 5. Lower pH (pH < 4) strongly inhibited K. michiganensis growth, while Cu stress and higher pH (pH > 5) induced Cu precipitation in the medium. Transcriptomic analyses indicated that two groups of genes related to quorum sensing (QS) systems (lsrABCDFGKR) and type II secretion systems (T2SS) (gspCDEFGHIJKLM) were significantly up-regulated at pH 4 only. These results suggest that T2SS may be induced and controlled by QS, thereby contributing to the formation of extracellular polymeric substances (EPS) and the secretion of proteins to prevent Cu ions from entering cells. Six Cu resistance genes (cusABF, copA, cueO, and gene05308) were more significantly up-regulated at pH 4 than at pH 5. In addition, the relative expression (log2|FC=) of the sulfur assimilation genes cysHJIK was relatively higher at pH 4 than at pH 5, while the gene encoding organic sulfur metabolism, tauB, was also significantly up-regulated at only pH 4. These results indicate that the Cu efflux system can remove intracellular Cu ions from cells, and that the sulfur assimilation system is related to the detoxification of Cu ions. Furthermore, increased free Cu ions at lower pH (4) could induce communication signals among cells, thereby stimulating the response of T2SS-related genes in K. michiganensis to tolerate Cu stress. Consequently, the resistance of K. michiganensis to Cu stress is a multisystem collaborative process composed of intracellular and extracellular components.


Asunto(s)
Cobre/toxicidad , Contaminantes Ambientales/toxicidad , Klebsiella/fisiología , Transcriptoma/fisiología , Cobre/metabolismo , Perfilación de la Expresión Génica , Iones , Klebsiella/genética
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