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1.
Ecotoxicol Environ Saf ; 203: 111001, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32888585

RESUMO

Environmental nanomaterials contamination is a great concern for organisms including human. Copper oxide nanoparticles (CuO NPs) are widely used in a huge range of applications which might pose potential risk to organisms. This study investigated the in vivo transgenerational toxicity on development and reproduction with parental CuO NPs exposure in the nematode Caenorhabditis elegans. The results showed that CuO NPs (150 mg/L) significantly reduced the body length of parental C. elegans (P0). Only about 1 mg/L Cu2+ (~0.73%) were detected from 150 mg/L CuO NPs in 0.5X K-medium after 48 h. In transgenerational assays, CuO NPs (150 mg/L) parental exposure significantly induced developmental and reproductive toxicity in non-exposed C. elegans progeny (CuO NPs free) on body length (F1) and brood size (F1 and F2), respectively. In contrast, parental exposure to Cu2+ (1 mg/L) did not cause transgenerational toxicity on growth and reproduction. This suggests that the transgenerational toxicity was mostly attributed to the particulate form of CuO NPs. Moreover, qRT-PCR results showed that the mRNA levels of met-2 and spr-5 genes were significantly decreased at P0 and F1 upon only maternal exposure to CuO NPs (150 mg/L), suggesting the observed transgenerational toxicity was associated with possible epigenetic regulation in C. elegans.


Assuntos
Caenorhabditis elegans/efeitos dos fármacos , Cobre/toxicidade , Epigênese Genética/efeitos dos fármacos , Nanopartículas/toxicidade , Animais , Caenorhabditis elegans/genética , Caenorhabditis elegans/crescimento & desenvolvimento , Caenorhabditis elegans/fisiologia , Feminino , Humanos , Exposição Materna/efeitos adversos , Reprodução/efeitos dos fármacos , Reprodução/genética
2.
J Environ Pathol Toxicol Oncol ; 39(3): 201-212, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32865912

RESUMO

Acute and chronic effects of ultraviolet radiation (UVR) on human health have long been a concern. It is well known that acute UVR causes epidermal hyperplasia, erythema, delayed tanning, pigment darkening, and free-radical formation. Apart from acute effects of UVR, its chronic effects involve immunosuppression, photoaging, exacerbation, photodermatoses, and photocarcinogenesis. To protect skin from harmful effects of UVR, UV filters were developed. But these may cause harmful effects in humans and on the environment; adverse effects of these chemicals have been evaluated for > 20 yr. Studies show that UV filters may lead to endocrine disruption, hepatotoxicity, mutagenicity, and systemic toxicity. Literature on environmental effects of UV filters suggests that they are bioaccumulative, pseudopersistent, and possibly toxic to aquatic ecosystems. The objective of this review is to summarize toxic effects and safety concerns of organic UV filters on human beings and the environment. We focus on UV filters' organic endocrine-disrupting effects by reviewing both in vivo and in vitro studies.


Assuntos
Disruptores Endócrinos/toxicidade , Compostos Orgânicos/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Reprodução/efeitos dos fármacos , Protetores Solares/toxicidade , Animais , Biotransformação , Disruptores Endócrinos/química , Disruptores Endócrinos/farmacocinética , Humanos , Estrutura Molecular , Compostos Orgânicos/química , Compostos Orgânicos/farmacocinética , Protetores Solares/química , Protetores Solares/farmacocinética
3.
Ecotoxicol Environ Saf ; 205: 111338, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-32956867

RESUMO

Lead (Pb) is well-recognized for its great hazards to human and wildlife health. It has negative influences on multiple organs and systems of birds. Especially, lead exposure caused adverse impacts on bird reproduction. In this study, one week old female Japanese quails were randomly allocated into four groups and each group was respectively fed with 0, 50 ppm, 500 ppm and 1000 ppm Pb in drinking water for 36 days to determine the effects of chronic lead exposure on ovarian development and function. The results showed that Pb did accumulate in the ovary and ovarian development was delayed by high dose lead exposure (500 ppm and 1000 ppm). Moreover, high Pb dosage induced ovarian histopathological damages characterized by granulosa cells disorganization, follicle atresia and interstitial cell degeneration. Meanwhile, the concentration of estradiol (E2) was significantly decreased and mRNA levels of genes involved with ovarian steroidogenesis were significantly down-regulated by high concentration Pb. In addition, Pb exposure caused increasing cell apoptosis and significant changes of the expression of genes involved with cell death in the ovary. High dose Pb exposure also inhibited thyroid hormone release and disrupted ovarian thyroid deiodination apart from causing thyroid histopathological injury such as follicular deformation and atrophy. The study indicated that Pb might cause ovarian malfunction by inducing ovary and thyroid microstructural damages, thyroid hormone and estrogen release inhibition and ovarian steroidogenesis disruption.


Assuntos
Coturnix/metabolismo , Poluentes Ambientais/toxicidade , Estradiol/metabolismo , Expressão Gênica/efeitos dos fármacos , Chumbo/toxicidade , Ovário/efeitos dos fármacos , Hormônios Tireóideos/metabolismo , Adolescente , Animais , Apoptose/efeitos dos fármacos , Coturnix/genética , Coturnix/crescimento & desenvolvimento , Relação Dose-Resposta a Droga , Poluentes Ambientais/metabolismo , Estradiol/genética , Feminino , Células da Granulosa/efeitos dos fármacos , Células da Granulosa/patologia , Humanos , Chumbo/metabolismo , Folículo Ovariano/efeitos dos fármacos , Folículo Ovariano/patologia , Ovário/crescimento & desenvolvimento , Ovário/metabolismo , Ovário/patologia , Distribuição Aleatória , Reprodução/efeitos dos fármacos , Reprodução/genética , Glândula Tireoide/efeitos dos fármacos , Glândula Tireoide/metabolismo , Glândula Tireoide/patologia , Hormônios Tireóideos/genética
4.
Aquat Toxicol ; 227: 105592, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32891020

RESUMO

International shipping is responsible for the release of numerous contaminants to the air and the marine environment. In order to reduce airborne emissions, a global 0.5 % sulphur limit for marine fuels was implemented in January 2020. Recently, a new generation of so-called hybrid fuels that meet these new requirements have appeared on the market. Studies have shown that these fuels have physical properties that make conventional clean-up methods difficult, but few have studied their effects on marine life. We conducted short and long-term microcosm experiments with natural mesozooplankton communities exposed to the water accommodated fractions (WAFs) of the hybrid fuel RMD80 (0.1 % sulphur) and a Marine Gas Oil (MGO). We compared the toxicity of both fuel types in 48h short-term exposures, and studied the effects of the hybrid fuel on community structure over two generations in a 28-day experiment. The F0 generation was exposed for eight days and the F1 generation was raised for 22 days without exposure. GC-MS and GC-FID analysis of the WAFs revealed that the hybrid fuel was dominated by a mixture of volatile organic compounds (VOCs) and poly aromatic hydrocarbons (PAHs), whereas the MGO was mainly composed of VOCs. We observed significant short-term effects on copepod egg production from exposure to 25 % hybrid fuel WAF, but no effects from the MGO WAF at equivalent WAF dilution. In the long-term experiment with RMD80, the feeding rate was initially increased after exposure to 0.5-1.1 % hybrid fuel WAF, but this did not increase the copepod egg production. Significant change in community structure was observed after eight days in the F0 community at 0.5-3.3 % WAF. Indications of further alterations in species abundances was observed in the F1 community. Our results demonstrate that the MGO is a less toxic low-sulphur alternative to the hybrid fuel for marine zooplankton, and that a hybrid fuel spill could result in altered diversity of future generations of copepod communities.


Assuntos
Copépodes/efeitos dos fármacos , Óleos Combustíveis/toxicidade , Hidrocarbonetos Aromáticos/toxicidade , Enxofre/toxicidade , Poluentes Químicos da Água/toxicidade , Zooplâncton/efeitos dos fármacos , Animais , Copépodes/fisiologia , Relação Dose-Resposta a Droga , Óleos Combustíveis/análise , Hidrocarbonetos Aromáticos/química , Modelos Teóricos , Reprodução/efeitos dos fármacos , Navios , Enxofre/química , Fatores de Tempo , Poluentes Químicos da Água/química , Zooplâncton/fisiologia
5.
Aquat Toxicol ; 227: 105569, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32916319

RESUMO

Pharmaceuticals are widespread contaminants across the aquatic systems and despite the role that these compounds play in society today, little is known about their effects in aquatic organisms once they are released into the environment. This study aims to provide quantitative insight on the effects of antidepressants on the reproduction of fish and crustaceans with a multilevel meta-analysis. A systematic literature search identified 19 studies investigating effects of antidepressant exposure in fish or crustaceans' reproduction, according to specific selection criteria. Heterogeneity analysis was performed and the moderating effect of the range of exposure concentrations, exposure time, organism group and toxicant was tested. Additionally, publication bias was also addressed. The results showed that, overall, there is no significant association between antidepressant exposure and the reproduction of fish and crustaceans, however, moderator analysis revealed that the range of concentrations is a significant moderator for fish and crustacean fecundity, showing contrary results between the two groups. Antidepressant concentration had a small, yet positive effect on fish fecundity, meaning that increased concentrations resulted in increased fish fecundity, whilst a negative effect on crustaceans' fecundity was apparent with increasing concentrations. This difference could be related to data artifacts, or, more likely, evidencing a hormetic dose-response curve, with different ranges of exposure concentrations considered in studies on fish and crustaceans. Antidepressants have shown effects on reproductive outcomes in aquatic organisms, based on individual studies and narrative reviews. However, our results show that other factors can have an important role. Additionally, data available for a quantitative assessment is scarce, focusing mainly on a few freshwater species, low concentration ranges and one SSRI compound, fluoxetine. Thus, more research on the subject is needed since meta-analysis are only as statistically powerful as the number of, good quality, studies they include.


Assuntos
Antidepressivos/toxicidade , Organismos Aquáticos/efeitos dos fármacos , Fluoxetina/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Organismos Aquáticos/fisiologia , Crustáceos/efeitos dos fármacos , Peixes/crescimento & desenvolvimento , Água Doce/química , Reprodução/efeitos dos fármacos
6.
J Toxicol Sci ; 45(8): 411-422, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32741894

RESUMO

Lanthanum oxide (La2O3) nanoparticles (NPs) have been widely used in photoelectric and catalytic applications. However, their exposure and reproductive toxicity is unknown. In this study, the effect of the intragastric administration of two different-sized La2O3 particles in the testes of mice for 60 days was investigated. Although the body weight of mice treated or not treated with La2O3 NPs was not different and La2O3 NPs were distributed in the organs including the testis, liver, kidney, spleen, heart and brain. La2O3 NPs accumulate more than micro-sized La2O3 (MPs) in mice testes. The histopathological evaluation showed that moderate reproductive toxicity induced by La2O3 NPs in the testicle tissues. Furthermore, increased MDA, 8-OHdG levels and decreased SOD activities were detected in the La2O3 NP-treated groups. Moreover, qRT-PCR and western blotting data indicated that La2O3 NPs affecting the blood-testis barrier (BTB)-related genes in mice testes. Taken together, these findings suggested that La2O3 NPs activated inflammation responses and cross the BTB in the murine testes. This study provided useful information for risk analysis and regulation of La2O3 NPs by administrative agencies.


Assuntos
Lantânio/administração & dosagem , Lantânio/toxicidade , Nanopartículas Metálicas/toxicidade , Óxidos/administração & dosagem , Óxidos/toxicidade , Tamanho da Partícula , Reprodução/efeitos dos fármacos , Testículo/efeitos dos fármacos , Administração Oral , Animais , Barreira Hematotesticular/metabolismo , Desoxiadenosinas/metabolismo , Expressão Gênica/efeitos dos fármacos , Inflamação , Lantânio/metabolismo , Masculino , Malondialdeído/metabolismo , Nanopartículas Metálicas/administração & dosagem , Camundongos , Óxidos/metabolismo , Superóxido Dismutase/metabolismo , Testículo/metabolismo , Distribuição Tecidual
7.
Int J Nanomedicine ; 15: 5227-5237, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32801688

RESUMO

Background: Large-scale production and application of amorphous silica nanoparticles (SiNPs) have enhanced the risk of human exposure to SiNPs. However, the toxic effects and the underlying biological mechanisms of SiNPs on Caenorhabditis elegans remain largely unclear. Purpose: This study was to investigate the genome-wide transcriptional alteration of SiNPs on C. elegans. Methods and Results: In this study, a total number of 3105 differentially expressed genes were identified in C. elegans. Among them, 1398 genes were significantly upregulated and 1707 genes were notably downregulated in C. elegans. Gene ontology analysis revealed that the significant change of gene functional categories triggered by SiNPs was focused on locomotion, determination of adult lifespan, reproduction, body morphogenesis, multicellular organism development, endoplasmic reticulum unfolded protein response, oocyte development, and nematode larval development. Meanwhile, we explored the regulated effects between microRNA and genes or signaling pathways. Pathway enrichment analysis and miRNA-gene-pathway-network displayed that 23 differential expression microRNA including cel-miR-85-3p, cel-miR-793, cel-miR-241-5p, and cel-miR-5549-5p could regulate the longevity-related pathways and inflammation signaling pathways, etc. Additionally, our data confirmed that SiNPs could disrupt the locomotion behavior and reduce the longevity by activating ins-7, daf-16, ftt-2, fat-5, and rho-1 genes in C. elegans. Conclusion: Our study showed that SiNPs induced the change of the whole transcriptome in C. elegans, and triggered negative effects on longevity, development, reproduction, and body morphogenesis. These data provide abundant clues to understand the molecular mechanisms of SiNPs in C. elegans.


Assuntos
Caenorhabditis elegans/efeitos dos fármacos , Caenorhabditis elegans/genética , Regulação da Expressão Gênica/efeitos dos fármacos , Nanopartículas/toxicidade , Animais , Proteínas de Caenorhabditis elegans/genética , Redes Reguladoras de Genes/efeitos dos fármacos , Genoma Helmíntico , Humanos , Longevidade/efeitos dos fármacos , MicroRNAs/genética , Testes de Mutagenicidade/métodos , Nanopartículas/química , Reprodução/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Dióxido de Silício/química , Dióxido de Silício/toxicidade , Transcriptoma , Resposta a Proteínas não Dobradas/genética
8.
J Environ Radioact ; 222: 106365, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32750598

RESUMO

Concentration of uranium (U), a naturally encountered radioactive element in earth's crust, can be enhanced in freshwater ecosystems (µg.L-1 - mg.L-1) due to various anthropogenic activities. The consequent aquatic organism exposure to U leads to its accumulation in all organs, particularly in the gonad, and in subcellular fractions (mainly the cytosol); then it is known to affect fish at several biological levels, and more particularly, at a reproduction endpoint, with a decrease in the total number of eggs, spawn events and larvae survival. The understanding of U reprotoxicity requires the fine knowledge of its speciation at molecular level, i.e., its interaction with cytosolic biomolecules. In this study, we focus on the U-protein interactions in gonads. A non-denaturating extraction protocol combined with size exclusion chromatography (SEC) allowed the separation of metal-protein complexes in ovaries of U-contaminated wild roaches before their elemental detection (ICP MS). This enables unprecedented information to be obtained about U distribution in ovaries of autochthonous fish, Rutilus rutilus, which is different in some points from that obtained in the model species, Danio rerio under controlled laboratory conditions at a similar concentration level. Finally, the ability to transpose results from model to autochthonous fish was briefly discussed.


Assuntos
Monitoramento de Radiação , Reprodução , Urânio , Poluentes Radioativos da Água , Animais , Cyprinidae , Ecossistema , Feminino , Ovário/química , Reprodução/efeitos dos fármacos , Urânio/farmacocinética , Urânio/toxicidade , Poluentes Radioativos da Água/farmacocinética , Poluentes Radioativos da Água/toxicidade , Peixe-Zebra
9.
J Med Life ; 13(2): 138-143, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32742504

RESUMO

Treatment with anticancer drugs such as cyclophosphamide can harm the male reproductive system. Vitamin C and zinc are micronutrients with antioxidant activity and are the essential components of semen. Therefore, this study aimed to evaluate whether cyclophosphamide-exposed mice can recover from fertility with vitamin C and zinc therapy. In this experimental study, fifty male mice were divided into five groups. Groups 1-4 received cyclophosphamide (100 mg/kg, once a week for eight weeks). Also, group 2 received zinc (200 mg/kg), group 3 received vitamin C (300 mg/kg), group 4 received zinc and vitamin C (200 mg/kg and 300 mg/kg, respectively), five times per week for eight weeks, and group 5 received normal saline once a week and water five days a week for eight weeks. The data collected were statistically analyzed using SPSS 22. Results showed a significant increase in mount latency and a significant decrease in the number of sperms in the cyclophosphamide group compared to the control group. However, mount latency has been significantly decreased in mice treated with cyclophosphamide plus zinc compared to the cyclophosphamide group. The study also showed that the sperm count in the group that received cyclophosphamide and zinc had been increased compared to the cyclophosphamide group; the other treatments have decreased mount latency and increased the sperm count compared to the group treated with cyclophosphamide but not significantly. The Tubule Differentiation Index showed an increase in the cyclophosphamide-Zinc-Vitamin C group in comparison with the cyclophosphamide group. The current study showed that zinc could improve cyclophosphamide-induced toxicity of the reproductive system in male mice.


Assuntos
Antineoplásicos/efeitos adversos , Antioxidantes/farmacologia , Ácido Ascórbico/farmacologia , Substâncias Protetoras/farmacologia , Reprodução/efeitos dos fármacos , Zinco/farmacologia , Animais , Ácido Ascórbico/administração & dosagem , Ciclofosfamida/efeitos adversos , Hormônios/metabolismo , Humanos , Masculino , Camundongos , Comportamento Sexual Animal/efeitos dos fármacos , Contagem de Espermatozoides , Motilidade Espermática/efeitos dos fármacos , Espermatozoides/efeitos dos fármacos
10.
Chemosphere ; 260: 127594, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32673874

RESUMO

Salinization of freshwater ecosystems caused by human activities and climate change is a global problem that threatens freshwater resources and aquatic organisms. The aggravation of salinization and the presence of cyanobacterial blooms may pose a serious threat to crustacean zooplankton Daphnia. To test the consequences of these effects, we exposed Daphnia magna to the combined treatments of different chloride concentrations and three food compositions (100% Chlorella pyrenoidosa, 90% C. pyrenoidosa + 10% toxic Microcystis aeruginosa, 80% C. pyrenoidosa + 20% toxic M. aeruginosa) for 21 days, recorded relevant life history indicators, and fitted them using Sigmoidal and Gaussian model if appropriate. Results showed that both increased chloride and the presence of toxic M. aeruginosa in the food had significantly negative effects on key life history traits and clearance rate, and the two factors also had a significant interaction on the survival, development, and reproduction of D. magna. The maximum values of the key life-history traits and clearance rate, the median effect chloride concentrations, and the optimal chloride concentrations derived from the models showed that the survival, reproduction, and clearance rate of D. magna were threatened by high chloride concentrations, which were exacerbated by the presence of toxic M. aeruginosa, but lower concentration of chloride was beneficial to D. magna to resist toxic M. aeruginosa. In conclusion, the combined effects of increasing chloride concentration and cyanobacterial blooms have severely adverse impacts on cladocerans, which may cause cladocera population to decline more rapidly and potentially disrupt the food webs of aquatic ecosystems.


Assuntos
Adaptação Fisiológica/efeitos dos fármacos , Daphnia/efeitos dos fármacos , Água Doce/química , Microcystis/crescimento & desenvolvimento , Cloreto de Sódio/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Chlorella/crescimento & desenvolvimento , Daphnia/crescimento & desenvolvimento , Daphnia/fisiologia , Ecossistema , Cadeia Alimentar , Humanos , Traços de História de Vida , Reprodução/efeitos dos fármacos
11.
Chemosphere ; 259: 127221, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32615454

RESUMO

Due to its unique properties, graphene oxide (GO) has potential for biomedical and electronic applications, however environmental contamination including aquatic ecosystem is inevitable. Moreover, potential risks of GO in aquatic life are inadequately explored. Present study was designed to evaluate GO as an endocrine disrupting chemical (EDC) using the model Japanese medaka (Oryzias latipes). GO was injected intraperitoneally (25-200 µg/g) once to breeding pairs and continued pair breeding an additional 21 days. Eggs laid were analyzed for fecundity and the fertilized eggs were evaluated for developmental abnormalities including hatching. Histopathological evaluation of gonads, liver, and kidneys was made 21 days post-injection. LD50 was found to be sex-dependent. Fecundity tended to reduce in a dose-dependent manner during early post-injection days; however, the overall evaluation showed no significant difference. The hatchability of embryos was reduced significantly in the 200 µg/g group; edema (yolk and cardiovascular) and embryo-mortality remained unaltered. Histopathological assessment identified black particles, probably agglomerated GO, in the gonads of GO-treated fish. However, folliculogenesis in stromal compartments of ovary and the composition of germinal elements in testis remained almost unaltered. Moreover, granulosa and Leydig cells morphology did not indicate any significant EDC-related effects. Although liver and kidney histopathology did not show GO as an EDC, some GO-treated fish accumulated proteinaceous fluid in hepatic vessels and induced hyperplasia in interstitial lymphoid cells (HIL) located in kidneys. GO agglomerated in medaka gonads after 21-days post-injection. However, gonad histopathology including granulosa and Leydig cells alterations were associated with GO toxicity rather than EDC effects.


Assuntos
Grafite/toxicidade , Oryzias/fisiologia , Reprodução/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Animais , Ecossistema , Disruptores Endócrinos/toxicidade , Feminino , Fertilidade/efeitos dos fármacos , Gônadas/efeitos dos fármacos , Fígado/efeitos dos fármacos , Masculino , Ovário/efeitos dos fármacos , Testículo/efeitos dos fármacos
12.
Aquat Toxicol ; 225: 105553, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32622090

RESUMO

Endocrine disrupting chemicals (EDCs) can induce abnormalities in organisms via alteration of molecular pathways and subsequent disruption of endocrine functions. Bisphenol A (BPA) and 17α-ethinylestradiol (EE2) are ubiquitous EDCs in the environment. Many aquatic organisms, including fish, are often exposed to varying concentrations of BPA and EE2 throughout their lifespan. Both BPA and EE2 can activate estrogenic signaling pathways and cause adverse effects on reproduction via alteration of pathways associated with steroidogenesis. However, transcriptional pathways that are affected by chronic exposure to these two ubiquitous environmental estrogens during embryonic, larval, and juvenile stages are not clearly understood. In the present study, we examined transcriptional alterations in the testis of medaka fish (Oryzias latipes) chronically exposed to a low concentration of BPA or EE2. Medaka were exposed to BPA (10 µg/L) or EE2 (0.01 µg/L) from 8 h post-fertilization (as embryos) to adulthood 50 days post fertilization (dpf), and transcriptional alterations in the testis were examined by RNA sequencing (RNA-seq). Transcriptomic profiling revealed 651 differentially expressed genes (DEGs) between BPA-exposed and control testes, while 1475 DEGs were found between EE2-exposed and control testes. Gene ontology (GO) analysis showed a significant enrichment of "intracellular receptor signaling pathway", "response to steroid hormone" and "hormone-mediated signaling pathway" in the BPA-induced DEGs, and of "cilium organization", "microtubule-based process" and "organelle assembly" in the EE2-induced DEGs. Pathway analysis showed significant enrichment of "integrin signaling pathway" in both treatment groups, and of "cadherin signaling pathway", "Alzheimer disease-presenilin pathway" in EE2-induced DEGs. Single nucleotide polymorphism (SNP) and insertion-deletion (Indel) analysis found no significant differences in mutation rates with either BPA or EE2 treatments. Taken together, global gene expression differences in testes of medaka during early stages of gametogenesis were responsive to chronic BPA and EE2 exposure.


Assuntos
Compostos Benzidrílicos/toxicidade , Etinilestradiol/toxicidade , Oryzias/fisiologia , Fenóis/toxicidade , Testículo/fisiologia , Poluentes Químicos da Água/toxicidade , Animais , Disruptores Endócrinos/metabolismo , Estrogênios/metabolismo , Etinilestradiol/metabolismo , Feminino , Perfilação da Expressão Gênica , Larva/efeitos dos fármacos , Masculino , Reprodução/efeitos dos fármacos , Testículo/efeitos dos fármacos
13.
Aquat Toxicol ; 226: 105556, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32652413

RESUMO

Ribosomal (r)DNA is a highly dynamic, conserved, multigene family whose sequence homogeneity is thought to be maintained by intra- and interchromosomal recombination, which are capable of changing rDNA copy number. It is generally not known how environmental stress such as sublethal exposure to environmentally relevant concentrations of metals impacts rDNA copy number. To determine how chronic metal exposure affects rDNA, we measured copy number of the 18S rRNA gene in 355 copper and nickel-exposed samples and 132 metal-free samples derived from 325 mutation accumulation (MA) lines of two genetically distinct Daphnia pulex lineages. The MA lines were sampled at four time points over 100+ generations of clonal propagation. The copy number of rDNA was also measured in 15 individuals sampled from a metal-free non-MA control population established from the same progenitor as one of the MA lineages. We found that mean rDNA copy number fluctuated across lines exposed to metals with a tendency to decrease over time. In contrast, mean rDNA copy number in the metal-free control lines and the non-MA population remained stable over time. It is generally accepted that extreme rDNA loss results in the loss of organism fitness. Thus, fluctuations in rDNA copy number, including losses, could affect the long-term viability of natural populations of Daphnia in metal-contaminated habitats.


Assuntos
Variações do Número de Cópias de DNA/efeitos dos fármacos , DNA Ribossômico/genética , Daphnia/efeitos dos fármacos , Metais Pesados/toxicidade , Acúmulo de Mutações , Poluentes Químicos da Água/toxicidade , Animais , Cobre/toxicidade , Daphnia/genética , Níquel/toxicidade , RNA Ribossômico 18S/genética , Reprodução/efeitos dos fármacos , Reprodução/genética
14.
Chemosphere ; 258: 127383, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32559491

RESUMO

The application of pesticides typically leads to lethal and sublethal exposure of non-target insects. Whereas our current understanding of these sublethal effects typically focuses on reproductive and physiological parameters, recent works emphasize that sublethal effects on behaviors such as maternal care could be of major importance in non-target species. However, it remained unknown whether these sublethal effects occur in insects. Here, we tested if exposure to sublethal doses of deltamethrin - a pyrethroid insecticide commonly used in crops - alters the expression of maternal egg care in females of the European earwig Forficula auricularia, a predator insect and pest control. Our results first reveal that deltamethrin exposure impaired the expression of three forms of maternal egg care: It decreased the likelihood of mothers to gather their otherwise scattered clutch of eggs, increased the time during which the female abandoned the clutch after a predator attack and reduced egg grooming duration. These sublethal effects did not reflect a lower activity of deltamethrin-exposed females, as these females increased their expression of self-grooming, and deltamethrin exposure did not affect females' exploration and mobility. Finally, we found that the negative effects of deltamethrin on egg care did not modify egg development, hatching rate and juvenile weight, possibly due to the transient effects of deltamethrin on maternal behaviors. Overall, our results reveal that sublethal exposure to a pesticide may diminish maternal egg care in a natural pest control and call for the integration of this measurement in assays on pesticides application.


Assuntos
Comportamento Animal/efeitos dos fármacos , Insetos/efeitos dos fármacos , Inseticidas/toxicidade , Comportamento Materno/efeitos dos fármacos , Nitrilos/toxicidade , Óvulo/crescimento & desenvolvimento , Piretrinas/toxicidade , Animais , Relação Dose-Resposta a Droga , Feminino , Insetos/fisiologia , Reprodução/efeitos dos fármacos
15.
Toxicol Appl Pharmacol ; 401: 115077, 2020 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-32479917

RESUMO

Triclocarban (TCC) is an antimicrobial compound, widely used in personal care products, such as soaps, toothpaste, and shampoo. This agent is incompletely removed by wastewater treatment and represents an environmental contaminant. Studies show that TCC has been associated with some endocrine disruptions. In vitro, TCC demonstrated potent androgen-augmenting activity and aromatase inhibition. In this sense, exposure during critical periods of development (gestation and lactation) could lead to some adverse health outcomes in offspring. Therefore, the present study evaluated if maternal exposure to three different doses of TCC could interfere in the reproductive parameters of male offspring. Pregnant female Wistar rats were separated into four groups: vehicle Control (CTR); TCC 0.3 mg/kg (TCC 0.3); TCC 1.5 mg/kg (TCC 1.5); TCC 3.0 mg/kg (TCC 3.0). Dams were treated daily by oral gavage from gestational day 0 to lactational day 21. The males were evaluated in different timepoint: infancy (PND 21), puberty (PND 50) and adult life (PND 90-120). The histomorphometric analysis of testis and testosterone level were assessed on PND 21, 50, 120; sexual behavior and sperm parameters at adulthood. In the TCC 3.0 group, a decrease in the testis interstitial volume and an increase in testosterone levels were observed on PND 21. Moreover, there was a decrease in the diameter of the seminiferous tubules on PND 50, and a decrease in sexual competency in adulthood. These results suggest that exposure to a human relevant dose of TCC may interfere with reproduction and could have implications for human health.


Assuntos
Anti-Infecciosos Locais/toxicidade , Carbanilidas/toxicidade , Lactação/efeitos dos fármacos , Efeitos Tardios da Exposição Pré-Natal/induzido quimicamente , Reprodução/efeitos dos fármacos , Comportamento Sexual Animal/efeitos dos fármacos , Fatores Etários , Animais , Feminino , Lactação/fisiologia , Masculino , Gravidez , Efeitos Tardios da Exposição Pré-Natal/sangue , Efeitos Tardios da Exposição Pré-Natal/patologia , Ratos , Ratos Wistar , Reprodução/fisiologia , Comportamento Sexual Animal/fisiologia , Testículo/efeitos dos fármacos , Testículo/patologia , Testosterona/sangue
16.
Ecotoxicol Environ Saf ; 201: 110813, 2020 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-32544745

RESUMO

The bioaccumulation potential and toxic effects of engineered nanomaterials (ENMs) to earthworms are poorly understood. Two studies were conducted following OECD TG 222 on Eisenia fetida to assess the effects of CdTe QDs with different coatings and soil ageing respectively. Earthworms were exposed to carboxylate (COOH), ammonium (NH4+), or polyethylene glycol (PEG) coated CdTe QDs, or a micron scale (bulk) CdTe material, at nominal concentrations of 50, 500 and 2000 mg CdTe QD kg-1 dry weight (dw) for 28 days in Lufa 2.2 soil. In the fresh soil study, earthworms accumulated similar amounts of Cd and Te in the CdTe-bulk exposures, while the accumulation of Cd was higher than Te during the exposures to CdTe QDs. However, neither the total Cd, nor Te concentrations in the earthworms, were easily explained by the extractable metal fractions in the soil or particle dissolution. There were no effects on survival, but some retardation of growth was observed at the higher doses. Inhibition of Na+/K+-ATPase activity with disturbances to tissue electrolytes, as well as tissue Cu and Mn were observed, but without depletion of total glutathione in the fresh soil experiment. Additionally, juvenile production was the most sensitive endpoint, with estimated nominal EC50 of values >2000, 108, 65, 96 mg CdTe kg-1 for bulk, PEG-, COOH- and NH4+-coated CdTe QDs, respectively. In the aged soil study, the accumulation of Cd and Te was higher than in the fresh soil study in all CdTe QD exposures. Survival of the adult worms was reduced in the top CdTe-COOH and -NH4+ QD exposures by 55 ±â€¯5 and 60 ±â€¯25%, respectively; and with decreases in growth. The nominal EC50 values for juvenile production in the aged soil were 165, 88, 78 and 63 mg CdTe kg-1 for bulk, PEG-, COOH- and NH4+-coated CdTe QDs, respectively. In conclusion, exposure to nanoscale CdTe QDs, regardless of coating, caused more severe toxic effects that the CdTe bulk material and the toxicity increased after soil ageing. There were some coating-mediated effects, likely due to differences in the metal content and behaviour of the materials.


Assuntos
Compostos de Cádmio/toxicidade , Oligoquetos/efeitos dos fármacos , Pontos Quânticos/toxicidade , Poluentes do Solo/toxicidade , Solo/química , Telúrio/toxicidade , Animais , Bioacumulação , Compostos de Cádmio/química , Compostos de Cádmio/metabolismo , Modelos Teóricos , Oligoquetos/metabolismo , Tamanho da Partícula , Pontos Quânticos/química , Pontos Quânticos/metabolismo , Reprodução/efeitos dos fármacos , Poluentes do Solo/química , Poluentes do Solo/metabolismo , Propriedades de Superfície , Telúrio/química , Telúrio/metabolismo , Fatores de Tempo
17.
Bull Environ Contam Toxicol ; 105(2): 244-249, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32556691

RESUMO

The aim of the study was to assess the effects of silver nanoparticles (AgNPs1 = 2.7 d·nm, AgNPs2 = 6.5 d·nm) and silver nitrate (AgNO3) on Enchytraeus crypticus and Folsomia candida using toxicity tests (OECD Guideline 220, 232). A 28-day chronic toxicity study was performed to evaluate the reproduction and mortality rate. E. crypticus reproduction was more sensitive to AgNO3 with a 28dEC50 of 86.40 (62.52-119.4) mg·kg-1 dry weight (d.w.) compared to AgNPs1 (28dEC50 = 119.3 (60.4-235.6) mg·kg-1 d.w). Similarly, the reproduction of F. candida was inhibited the most by AgNO3 with a 28dEC50 of 126.2 (104.2-152.9) mg·kg-1 d.w. followed by AgNPs1 (28dEC50 = 158.7 (64.05-393.2) mg·kg-1 d.w.) and AgNPs2 (28dEC50 = 206.4 (181.9-234.1) mg·kg-1 d.w.). No mortalities were observed for tested soil invertebrates exposed to AgNPs at concentrations up to 166 mg·kg-1 d.w. of AgNPs1 and 300 mg·kg-1 d.w. of AgNPs2, respectively. It was found that silver ions are more toxic in comparison with AgNPs.


Assuntos
Artrópodes/efeitos dos fármacos , Nanopartículas Metálicas/toxicidade , Oligoquetos/efeitos dos fármacos , Nitrato de Prata/toxicidade , Prata/toxicidade , Poluentes do Solo/toxicidade , Animais , Íons , Nanopartículas Metálicas/química , Reprodução/efeitos dos fármacos , Prata/química , Solo/química , Solo/normas , Poluentes do Solo/química , Testes de Toxicidade Crônica
18.
Ecotoxicol Environ Saf ; 201: 110712, 2020 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-32502905

RESUMO

Exposure to manganese (Mn) can cause male reproductive damage and lead to abnormal secretion of sex hormones. Gonadotropin-releasing hormone (GnRH) plays an important role in the neuromodulation of vertebrate reproduction. Astrocytes can indirectly regulate the secretion of GnRH by binding paracrine prostaglandin E2 (PGE2) specifically to the EP1 and EP2 receptors on GnRH neurons. Prior studies assessed the abnormal secretion of GnRH caused by Mn exposure, but the specific mechanism has not been reported in detail. This study investigated the effects of Mn exposure on the reproductive system of male mice to clarify the role of PGE2 in the abnormal secretion of GnRH in the hypothalamus caused by exposure to Mn. Our data demonstrate that antagonizing the EP1 and EP2 receptors of PGE2 can restore abnormal levels of GnRH caused by Mn exposure. Mn exposure causes reduced sperm count and sperm shape deformities. These findings suggest that EP1 and EP2, the receptors of PGE2, may be the key to abnormal GnRH secretion caused by Mn exposure. Antagonizing the PGE2 receptors may reduce reproductive damage caused by Mn exposure.


Assuntos
Hormônio Liberador de Gonadotropina/metabolismo , Hipotálamo/efeitos dos fármacos , Manganês/toxicidade , Receptores de Prostaglandina E Subtipo EP1/metabolismo , Receptores de Prostaglandina E Subtipo EP2/metabolismo , Reprodução/efeitos dos fármacos , Animais , Hipotálamo/metabolismo , Masculino , Manganês/metabolismo , Camundongos , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Receptores de Prostaglandina E Subtipo EP1/antagonistas & inibidores , Receptores de Prostaglandina E Subtipo EP2/antagonistas & inibidores
19.
Int J Nanomedicine ; 15: 3415-3431, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32523341

RESUMO

Purpose: Lanthanum oxide (La2O3) nanoparticles (NPs) have been widely used in catalytic and photoelectric applications, but the reproductive toxicity is still unclear. This study evaluated the reproductive toxicity of two different-sized La2O3 particles in the testes. Materials and Methods: Fifty Kunming mice were randomly divided into five groups. Mice were treated with La2O3 NPs by repeated intragastric administration for 90 days (control, nano-sized with 5, 10, 50 mg/kg BW and micro-sized with 50 mg/kg BW). Mice in the control group were treated with de-ionised water without La2O3 NPs. Sperm parameters, testicular histopathology, TEM assessment, hormone assay and nuclear factor erythroid 2-related factor 2 (Nrf-2) pathway were performed and evaluated. Results: The body weight of mice treated with La2O3 NPs or not had no difference; sperm parameters and histological assessment showed that La2O3 NPs could induce reproductive toxicity in the testicle. Serum testosterone and gonadotropin-releasing hormone (GnRH) in the NH (nano-sized with 50 mg/kg BW) group were markedly decreased relative to control group, and an increase of luteinizing hormone (LH) in NH group was detected . Additionally, transmission electron microscopy revealed that the ultrastructural abnormalities induced by La2O3 NPs were more severe than La2O3 MPs in the testes. Furthermore, La2O3 NPs treatment inhibited the translocation of nuclear factor erythroid 2-related factor 2 (Nrf-2) from the cytoplasm into the nucleus as well as the expression of downstream genes NAD(P)H quinone oxidoreductase1 (NQO1), hemeoxygenase 1 (HO-1) and (glutathione peroxidase) GSH-Px, thus abrogating Nrf-2-mediated defense mechanisms against oxidative stress. Conclusions: The results of this study demonstrated that La2O3 NPs improved the spermatogenesis defects in mice. La2O3 NPs inhibited Nrf-2/ARE signaling pathway that resulted in apoptosis in the mice testes.


Assuntos
Elementos de Resposta Antioxidante/genética , Lantânio/toxicidade , Fator 2 Relacionado a NF-E2/metabolismo , Nanopartículas/toxicidade , Óxidos/toxicidade , Reprodução/efeitos dos fármacos , Transdução de Sinais , Animais , Apoptose/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Concentração de Íons de Hidrogênio , Inflamação/patologia , Lantânio/sangue , Masculino , Camundongos , Nanopartículas/ultraestrutura , Estresse Oxidativo/efeitos dos fármacos , Óxidos/sangue , Transdução de Sinais/efeitos dos fármacos , Espermatozoides/efeitos dos fármacos , Espermatozoides/metabolismo , Testículo/efeitos dos fármacos , Testículo/metabolismo , Testículo/patologia , Testículo/ultraestrutura , Testosterona/biossíntese , Testosterona/metabolismo
20.
Bull Environ Contam Toxicol ; 105(1): 62-66, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32556375

RESUMO

The various uses of copper or copper compounds in industrial, biocidal or pesticidal products lead to inputs of the metal into aquatic environments. To assess effects of copper ions on non-target organisms, the freshwater snail Theodoxus fluviatilis was used as test organism for a three-week laboratory experiment. Snails were exposed to four copper concentrations ranging from 4 to 39 µg Cu2+/L, and besides mortality, several sublethal parameters were evaluated. Concerning survival, an aqueous copper concentration of 6 µg/L was determined as NOEC, and 16 (± 0.1) µg/L as LC50. Negative sublethal effects on reproduction, activity and pathological modifications in the snails were detected in the treatment with an aqueous copper concentration of 15 µg/L. Our results using T. fluviatilis as a mere grazer exclusively feeding on biofilms contribute to findings that field relevant copper concentrations have a significant effect on non-target organisms in aquatic environments.


Assuntos
Cobre/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Água Doce , Íons , Reprodução/efeitos dos fármacos , Caramujos/efeitos dos fármacos
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