RESUMEN
An expert panel was assembled to evaluate reproductive toxicology study data and their application to health risk assessment to provide input on the data quality, interpretation, and application of data from three multi-generation reproductive toxicity studies of N-methylpyrrolidone (NMP). Panelists were engaged using a double-blinded, modified Delphi format that consisted of three rounds. Key studies were scored using the U.S. Environmental Protection Agency's (EPA) questions and general considerations to guide the evaluation of experimental animal studies for systematic review. The primary conclusions of the panel are that one of the studies (Exxon, 1991) is not a high-quality study due to several design flaws that includes: (1) exceedance of the maximum tolerable dose in the high dose group; (2) failure to adjust feed concentrations of NMP during the lactation period, resulting in NMP doses that were 2- to 3-fold higher than nominal levels; and/or (3) underlying reproductive performance problems in the strain of rats used. For these reasons, the panel recommended that this study should not be considered for quantitative risk assessment of NMP. Exclusion of this study, and its corresponding data for male fertility and female fecundity, from the quantitative risk assessment results in a change in the identification of the most sensitive endpoint. Instead, changes in rat fetal/pup body weight, an endpoint previously selected by EPA, was identified as an appropriate basis for human health risk assessment based on a consideration of the best available science and weight of scientific evidence supported by the NMP toxicity database.
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Pirrolidinonas , Reproducción , Humanos , Ratas , Masculino , Animales , Femenino , Pirrolidinonas/toxicidad , Peso Fetal , Medición de RiesgoRESUMEN
n-Methyl-2-pyrrolidone (NMP) is a widely used solvent with a mild amine-like odor that can exist in a vapor or aerosol at moderate temperatures. In humans, NMP was reported to induce weak and transient eye irritation and headache. NMP was not a dermal sensitizer and has a low acute toxicity via oral, dermal, and inhalation routes. NMP was not genotoxic/mutagenic in a battery of in vitro and in vivo studies. Furthermore, NMP was not carcinogenic in rats although species-specific liver tumors were identified in mice. Chronic studies in the rat provided a NOAEL of 10 ppm (40 mg/m3) causing only minor effects in males (slightly reduced mean body weight) at 100 ppm (400 mg/m3). Developmental toxicity was considered the critical endpoint (decreased fetal body weights at non-maternally toxic doses). Benchmark dose and PBPK models were utilized to derive an internal dose of 350-470 mg·h/L as a NOAEL for this response and a human equivalent air concentration of 350-490 ppm. With the application of adjustment factors, an 8-h time-weighted average WEEL value of 15 ppm (60 mg/m3) was derived and is expected to provide a significant margin of safety against any potential adverse health effects in workers. To address the potential for respiratory irritation, a short-term exposure level of 30 ppm (120 mg/m3) was derived, and a skin notation is assigned because of the contribution of dermal absorption to the systemic toxicity of NMP.
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Exposición a Riesgos Ambientales , Lugar de Trabajo , Animales , Masculino , Ratones , Nivel sin Efectos Adversos Observados , Pirrolidinonas/toxicidad , RatasRESUMEN
Flurochloridone (FLC), a wildly used herbicide, could induce hepatotoxicity after long-term exposure to male rat, in addition to its reactive oxygen species (ROS)-dependent reproductive toxicity. The hepatotoxicity effect and mechanism was investigeted using 1, 10 and 100 µmolâ¯L-1 FLC treated BRL-3A liver cell in this study. The function of mitochondrial respiration, glycolysis rate and real time ATP production rate are determined by seahorse XF analyzer, and the bio-transformers of FLC, intermediates of TCA cycle and glycolysis, and related amino acids are determined and identified by [U-13C] Glucose metabolic flux technology based on UPLC-HRMS. The mRNA expression of cytochrome P450s and the key regulatory enzymes of glucose metabolism and γ- glutamyl cycle pathway. The protein expressions of protein kinase B (AKT) and glycogen synthase kinase-3 beta (GSK-3ß) were determined. The results show dechlorination and glutathione (GSH) conjugate products of FLC are predominant bio-transformmers after 24â¯h treatment in BRL-3A cell. FLC could enhance glycolysis function and inhibit mitochondrial aerobic respiratory, which is accompanied by the decreased total ATP level and ATP produced rate. Increased glucose-6-phosphate, fructose-6-phosphate, pyruvate and lactate levels, and elevated level of GSH and its precursor 5-glutamate-cysteine (γ-Glu-Cys) are observed in FLC treated cells, which indicates that energy metabolism dysfunction and GSH accumulation could be potentially mediated by activating γ- Glutamyl cycle pathway. Conclusively, FLC induced hepatotoxicity could be potentially related to some free radical reactions, including inhibiting mitochondrial function, glucose metabolism via glycolysis, regulating γ- glutamyl cycle pathway to promote reactive oxygen species (ROS) level, and then induced cell apoptosis by inhibiting AKT/GSK-3ß signal.
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Enfermedad Hepática Inducida por Sustancias y Drogas , Metabolismo Energético , Proteínas Proto-Oncogénicas c-akt , Pirrolidinonas , Adenosina Trifosfato/metabolismo , Animales , Línea Celular , Metabolismo Energético/efectos de los fármacos , Glucosa/metabolismo , Glutatión/metabolismo , Glucógeno Sintasa Quinasa 3 beta/metabolismo , Masculino , Proteínas Proto-Oncogénicas c-akt/metabolismo , Pirrolidinonas/toxicidad , Ratas , Especies Reactivas de Oxígeno/metabolismoRESUMEN
Flurochloridone (FLC), as a novel herbicide, has been widely used in many countries since 1980s. Current studies have shown that FLC has toxic effects on male reproduction and its target organ is testis, while the underlying mechanism is still unknown. Mouse testis Sertoli cell line TM4 cells were used as an in vitro model and treated with FLC at different doses (40, 80, 160 µM) for different times (6, 12, 24 h). Cell viability, cytotoxicity and apoptotic cells were detected by CCK-8 assay, LDH leakage assay and flow cytometry. The protein levels of GRP78, phosphorylated-eIF2α, ATF4, ATF6, CHOP, Bim and Bax were observed by Western Blot and Immunofluorescence staining. FLC inhibited cell viability and induced cytotoxicity in dose-dependent way in TM4 cells. The percentage of apoptotic cells were 6.2% ± 0.6%, 7.3% ± 0.3%, 9.8% ± 0.4%, 13.2% ± 0.2%, respectively. The expression levels of ER stress and UPR related proteins were activated over dose. Meanwhile, the pro-apoptotic proteins (Bim and Bax) were also up-regulated in dose-dependent. After pretreated with ISRIB, the inhibitor of eIF2α phosphorylation, the elevated expression of GRP78, phosphorylated-eIF2α, ATF4, ATF6, CHOP and Bim was down to normal level accordingly. In conclusion, FLC induced apoptosis in TM4 cells mediated by UPR signaling pathways.
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Estrés del Retículo Endoplásmico , Factor 2 Eucariótico de Iniciación , Pirrolidinonas , Factor de Transcripción Activador 6/metabolismo , Factor de Transcripción Activador 6/farmacología , Animales , Apoptosis , Estrés del Retículo Endoplásmico/efectos de los fármacos , Factor 2 Eucariótico de Iniciación/metabolismo , Factor 2 Eucariótico de Iniciación/farmacología , Masculino , Ratones , Pirrolidinonas/farmacología , Pirrolidinonas/toxicidad , Células de Sertoli/metabolismo , Transducción de Señal , Proteína X Asociada a bcl-2RESUMEN
N-vinyl pyrrolidone (NVP) is produced up to several thousand tons per year as starting material for the production of polymers to be used in pharmaceutics, cosmetics and food technology. Upon inhalation NVP was carcinogenic in the rat, liver tumor formation is starting already at the rather low concentration of 5 ppm. Hence, differentiation whether NVP is a genotoxic carcinogen (presumed to generally have no dose threshold for the carcinogenic activity) or a non-genotoxic carcinogen (with a potentially definable threshold) is highly important. In the present study, therefore, the existing genotoxicity investigations on NVP (all showing consistently negative results) were extended and complemented with investigations on possible alternative mechanisms, which also all proved negative. All tests were performed in the same species (rat) using the same route of exposure (inhalation) and the same doses of NVP (5, 10 and 20 ppm) as had been used in the positive carcinogenicity test. Specifically, the tests included an ex vivo Comet assay (so far not available) and an ex vivo micronucleus test (in contrast to the already available micronucleus test in mice here in the same species and by the same route of application as in the bioassay which had shown the carcinogenicity), tests on oxidative stress (non-protein-bound sulfhydryls and glutathione recycling test), mechanisms mediated by hepatic receptors, the activation of which had been shown earlier to lead to carcinogenicity in some instances (Ah receptor, CAR, PXR, PPARα). No indications were obtained for any of the investigated mechanisms to be responsible for or to contribute to the observed carcinogenicity of NVP. The most important of these exclusions is genotoxicity. Thus, NVP can rightfully be regarded and treated as a non-genotoxic carcinogen and threshold approaches to the assessment of this chemical are supported. However, the mechanism underlying the carcinogenicity of NVP in rats remains unclear.
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Carcinógenos/toxicidad , Neoplasias Hepáticas/inducido químicamente , Pirrolidinonas/toxicidad , Animales , Pruebas de Carcinogenicidad , Ensayo Cometa , Relación Dosis-Respuesta a Droga , Femenino , Neoplasias Hepáticas/patología , Masculino , Pruebas de Micronúcleos , Pruebas de Mutagenicidad , Estrés Oxidativo/efectos de los fármacos , Ratas , Ratas WistarRESUMEN
N-methyl pyrrolidone (NMP) is an FDA approved molecule used as an excipient in pharmaceutical industry. Besides having a central role in formulation of drugs, the most important function of any excipient is to guarantee the safety of the medicine during and after its administration. Several studies have shown that exposure to NMP and especially in rats produce a gonadotoxic effect leading to infertility. However, the mechanisms underlying the effect of NMP on male reproduction are unknown. The aim of this study was to assess the reproductive toxicity of NMP in male rats and to elucidate the underlying mechanism. Male Sprague Dawley rats were injected intraperitoneally, twice/ week, at a dose of 108 mg/ 100 g of body weight with NMP. Analysis of reproductive parameters revealed testicular atrophy in NMP treated animals compared to control animals. Germ cell composition within the seminiferous tubules was disturbed and manifested in an increase in number of cells with fragmented DNA. A subsequent decrease in number of spermatocytes and spermatids was observed. Alpha screen assay shows that NMP acts at the concentrations we applied in vivo as a low affinity inhibitor for BRDT (testis specific bromodomain protein). BRDT inhibition is mirrored by a significant decrease in the expression of early stage spermatocyte markers (lmna, aurkc and ccna1), during which BRDT expression predominates. A significant decrease in testosterone levels was also observed. Since NMP interferes with spermatogenesis on various levels, its use in humans must be carefully monitored.
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Proteínas Cromosómicas no Histona/antagonistas & inhibidores , Proteínas Cromosómicas no Histona/metabolismo , Pirrolidinonas/toxicidad , Espermatogénesis/efectos de los fármacos , Teratógenos/toxicidad , Animales , Relación Dosis-Respuesta a Droga , Hormona Folículo Estimulante/sangre , Masculino , Unión Proteica/efectos de los fármacos , Unión Proteica/fisiología , Ratas , Ratas Sprague-Dawley , Espermatogénesis/fisiología , Testosterona/sangreRESUMEN
N-methyl-2-pyrrolidone (NMP) and γ-hydroxybutyrate acid (GHB) are synthetic solvents detected in the recreational drug market. GHB has sedative/hypnotic properties and is used for criminal purposes to compromise reaction ability and commit drug-facilitated sexual assaults and other crimes. NMP is a strong solubilizing solvent that has been used alone or mixed with GHB in case of abuse and robberies. The aim of this experimental study is to compare the acute pharmaco-toxicological effects of NMP and GHB on neurological signs (myoclonia, convulsions), sensorimotor (visual, acoustic, and overall tactile) responses, righting reflex, thermoregulation, and motor activity (bar, drag, and accelerod test) in CD-1 male mice. Moreover, since cardiorespiratory depression is one of the main adverse effects related to GHB intake, we investigated the effect of NMP and GHB on cardiorespiratory changes (heart rate, breath rate, oxygen saturation, and pulse distension) in mice. The present study demonstrates that NMP inhibited sensorimotor and motor responses and induced cardiorespiratory depression, with a lower potency and efficacy compared to GHB. These results suggest that NMP can hardly be used alone as a substance to perpetrate sexual assault or robberies.
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Drogas Ilícitas/toxicidad , Locomoción/efectos de los fármacos , Desempeño Psicomotor/efectos de los fármacos , Pirrolidinonas/toxicidad , Reflejo de Sobresalto/efectos de los fármacos , Oxibato de Sodio/toxicidad , Adyuvantes Anestésicos/toxicidad , Animales , Relación Dosis-Respuesta a Droga , Hipnóticos y Sedantes/toxicidad , Locomoción/fisiología , Masculino , Ratones , Ratones Endogámicos ICR , Modelos Animales , Desempeño Psicomotor/fisiología , Violación , Reflejo de Sobresalto/fisiología , Insuficiencia Respiratoria/inducido químicamente , Insuficiencia Respiratoria/fisiopatologíaRESUMEN
BACKGROUND: Fluorochloridone (FLC), a selective pyrrolidone herbicide, has been recognized as a potential endocrine disruptor and reported to induce male reproductive toxicity, but the underlying mechanism is unclear. The aim of this study was to investigate the mechanism of FLC-induced reproductive toxicity on male mice with particular emphasis on the role of autophagy in mice' TM4 Sertoli cells. METHODS: Adult C57BL/6 mice were divided into one control group (0.5% sodium carboxymethyl cellulose), and four FLC-treated groups (3,15,75,375 mg/kg). The animals (ten mice per group) received gavage for 28 days. After treatment, histological analysis, sperm parameters, the microstructure of autophagy and the expression of autophagy-associated proteins in testis were evaluated. Furthermore, to explore the autophagy mechanism, TM4 Sertoli cells were treated with FLC (0,40,80,160 µM) in vitro for 24 h. Cell activity and cytoskeletal changes were measured by MTT assay and F-actin immunofluorescence staining. The formation of autophagosome, accumulation of reactive oxygen species (ROS), expression of autophagy marker proteins (LC3, Beclin-1 and P62) and AKT-related pathway proteins (AKT, mTOR) were observed. The ROS scavenger N-acetylcysteine (NAC) and AKT agonist (SC79) were used to treat TM4 cells to observe the changes of AKT-mTOR pathway and autophagy. RESULTS: In vivo, it showed that FLC exposure caused testicular injuries, abnormality in epididymal sperm. Moreover, FLC increased the formation of autophagosomes, the accumulation of LC3II/LC3I, Beclin-1 and P62 protein, which is related to the degradation of autophagy. In vitro, FLC triggered TM4 cell autophagy by increasing the formation of autophagosomes and upregulating of LC3II/LC3I, Beclin-1 and P62 levels. In addition, FLC induced ROS production and inhibited the activities of AKT and mTOR kinases. The Inhibition of AKT/mTOR signaling pathways and the activation of autophagy induced by FLC could be efficiently reversed by pretreatment of NAC. Additionally, decreased autophagy and increased cell viability were observed in TM4 cells treated with SC79 and FLC, compared with FLC alone, indicating that FLC-induced autophagy may be pro-death. CONCLUSION: Taken together, our study provided the evidence that FLC promoted autophagy in TM4 Sertoli cells and that this process may involve ROS-mediated AKT/mTOR signaling pathways.
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Autofagia/efectos de los fármacos , Disruptores Endocrinos/farmacología , Herbicidas/farmacología , Proteínas Proto-Oncogénicas c-akt/fisiología , Pirrolidinonas/farmacología , Células de Sertoli/efectos de los fármacos , Transducción de Señal/fisiología , Serina-Treonina Quinasas TOR/fisiología , Acetatos/farmacología , Acetilcisteína/farmacología , Animales , Autofagia/fisiología , Benzopiranos/farmacología , Forma de la Célula , Herbicidas/toxicidad , Masculino , Ratones , Ratones Endogámicos C57BL , Pirrolidinonas/toxicidad , Distribución Aleatoria , Especies Reactivas de Oxígeno , Células de Sertoli/citología , Células de Sertoli/metabolismo , Espermatozoides/efectos de los fármacos , Espermatozoides/ultraestructuraRESUMEN
Glyphosate (GLY)-dicamba (DIC) and GLY-flurochloridone (FLC) are herbicide mixtures which are widely used for treating fallow containing glyphosate resistant weeds. The aim of this study was to evaluate the acute toxic effects and the prevailing interactions on stage 36 tadpoles of the anuran species Rhinella arenarum when exposed to equitoxic and non-equitoxic combinations of these herbicide combinations. Experiments were realized using the following combinations of commercial formulations: 48% GLY-based Credit® + 57.71% DIC-based Banvel® and 48% GLY-based Credit® + 25% FLC-based Twin Pack Gold®. GLY-DIC and GLY-FLC equitoxic mixtures were assayed mixing each constituent with an equivalent individual toxicity able to induce the same lethality effect. After 96 h of exposure, GLY-DIC and GLY-FLC equitoxic mixtures presented toxic unit 50 values (TU50 96h) of 1.74 (confidence interval: 1.58-1.92) and 1.54 (confidence interval: 1.46-1.62) respectively, indicating the presence of a weak antagonistic interaction as TU values were greater than 1. For their part, most non-equitoxic combinations of GLY-DIC and GLY-FLC tested did not significantly differ from additivity, the only exception being when DIC and FLC were fixed at 0.33 TUs, where a weak antagonism was observed. Overall, results indicate that the toxicity of both GLY-DIC and GLY-FLC mixtures to R. arenarum tadpoles vary from additive to slightly antagonistic, depending on the proportion of constituting herbicide formulations present in the mixture.
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Bufonidae , Dicamba/toxicidad , Glicina/análogos & derivados , Herbicidas/toxicidad , Larva/efectos de los fármacos , Animales , Anuros , Mezclas Complejas/toxicidad , Antagonismo de Drogas , Glicina/toxicidad , Pirrolidinonas/toxicidad , GlifosatoRESUMEN
Flurochloridone (FLC) is a widely used herbicide in developing countries. Although the testes are a target organ for FLC in rats, the adverse effects of FLC on testes have not been fully elucidated. To clarify them, we performed RNA-seq analysis using the testes of FLC-treated rats from our previous subchronic toxicity tests. Unilateral testes of three male rats from solvent control groupand three FLC-treated groups (3 mg/kg, 31.25 mg/kg and 125 mg/kg) were used for RNA extraction. A poly A selection protocol coupled with an Illumina TruSeq RNA-Seq library protocol was used to construct RNA-Seq libraries. Principal component analysis (PCA), differentially expressed gene (DEG) analysis, and hierarchical clustering analysis (HCA) were conducted using R. Gene Ontology (GO) term enrichment analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis were performed to understand the biological characteristics of the DEGs using the Database for Annotation, Visualization and Integrated Discovery (DAVID). The results indicated that many up-regulated DEGs were enriched in pathways associated with testicular injury, such as mitogen-activated protein kinase (MAPK) signaling, lysosome and focal adhesion. Many down-regulated DEGs were enriched in pathways associated with testicular reproduction function, such as sexual reproduction, spermatogenesis and germ cell development. Moreover, we confirmed the oral no-observed-adverse-effect level (NOAEL) of 3 mg/kg in subchronic toxicity test, because the overall testicular gene expression in 3 mg/kg FLC-treated group was similar to that of the solvent control group. In 31.25 mg/kg and 125 mg/kg groups, DEGs revealed that testicular injury was related to oxidative stress.
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Herbicidas/toxicidad , Pirrolidinonas/toxicidad , Análisis de Secuencia de ARN , Testículo/efectos de los fármacos , Animales , Perfilación de la Expresión Génica , Masculino , Ratas , Ratas Wistar , Especies Reactivas de Oxígeno/metabolismo , Transducción de Señal/efectos de los fármacos , Testículo/metabolismo , Proteína p53 Supresora de Tumor/fisiologíaRESUMEN
As a new and efficient selective pre-emergence herbicide, flurochloridone (FLC) has been widely promoted in recent years but readily results in residues in nature. As the primary producers and restorers of the water environment, aquatic plants are at risk of FLC exposure. In the present research, we studied the phytotoxicity of FLC in Lemna minor and Ceratophyllum demersum. The physiological and growth responses of these two aquatic plants exposed to different concentrations of FLC (0, 20, 100, 300, 1000, and 2000 µg/L) were measured. The results showed that FLC (≥ 20 µg/L) could cause serious photosynthesis pigment damage and bleaching in C. demersum and L. minor. Significant oxidative damage was observed in L. minor at 20 µg/L FLC, while there was no severe oxidative damage in C. demersum. At 100-300 µg/L FLC, peroxidase (POD) and superoxide dismutase (SOD) were activated to scavenge free radicals in L. minor, while POD acted as a protective enzyme in C. demersum. At higher concentrations of FLC (≥ 1000-2000 µg/L), L. minor reached less than healthy stability through the regulation of the antioxidant enzyme system and the chlorophyll a/b value. POD, SOD, and protein content returned to normal levels, and the growth parameters increased. However, in C. demersum, the enzymes POD and SOD and soluble protein were damaged, and oxidative stress reached the highest level at 1000-2000 µg/L FLC. Taken together, our results suggested that when treated with FLC, L. minor was more sensitive at lower doses (20 µg/L) and more adaptive at higher doses (1000-2000 µg/L) than C. demersum.
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Araceae , Herbicidas , Pirrolidinonas , Araceae/efectos de los fármacos , Clorofila A , Herbicidas/toxicidad , Pirrolidinonas/toxicidadRESUMEN
BACKGROUND: Fluorochloridone (FLC) is a widely used herbicide, and its target organs are testes and epididymides. The Globally Harmonized System of Classification and Labelling of Chemicals classified FLC as Level 2-possibly cause fertility or fetal damage (no relevant data support). The maximum residue levels of FLC in processed crops have been reviewed in the latest European Food Safety Authority (EFSA) report in 2018. However, the toxic effect of FLC on fertility and early embryonic development is limited, and the health risk assessment of FLC needs further consideration. This study investigated the potential effects of FLC on fertility and early embryonic development in rats. METHODS: One hundred rats of each sex were divided into four groups including three FLC-treated groups at doses of 2 mg/kg, 5 mg/kg and 15 mg/kg, and a vehicle control group (0.5% (w/v) sodium carboxymethyl cellulose). Male and female rats were dosed for 9 and 2 consecutive weeks, intragastrically, prior to cohabitation and lasted throughout the mating period for males and continued until Gestation Day 7 (GD7) for females. Parameters such as weights and coefficients of reproductive organs, epididymal sperm number and motility, indexes of copulation, fecundity and fertility indexes, mating period, estrous cycle, corporalutea number, implantations, live, dead and resorbed fetuses, preimplantation loss rate, and postimplantation loss rate were observed in this study. RESULTS: Obvious toxicity of male reproductive system was found at the dose of 15 mg/kg including decreases in testicular and epididymal weight, also in sperm motility rate. Whereas the increase in sperm abnormality rate was observed. However, no significant effects of FLC were found on lutea count, implantations count, fetuses count and weight, live fetuses count (rate), dead fetuses count (rate), resorbed fetuses count (rate), placentas weight, fetuses gender, preimplantation loss (rate) and postimplantation loss (rate). Furthermore, FLC had no adverse effects on fertility and early embryonic development in rats. CONCLUSION: The no-observable-adverse-effect level (NOAEL) of FLC on fertility and early embryonic development in rats was considered to be 5 mg/kg/day.
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Desarrollo Embrionario/efectos de los fármacos , Fertilidad/efectos de los fármacos , Genitales Masculinos/efectos de los fármacos , Herbicidas/toxicidad , Pirrolidinonas/toxicidad , Animales , Femenino , Masculino , Tamaño de los Órganos , Ratas , Motilidad Espermática/efectos de los fármacos , Testículo/efectos de los fármacos , Testículo/patologíaRESUMEN
This study focused on defining the in vitro behavior of amphiphilic poly-N-vinylpyrrolidone (Amph-PVP) nanoparticles toward whole blood, blood plasma and blood cells in order to assess nanoparticle blood compatibility. In addition, possible effects on endothelium cell growth/viability were evaluated. The Amph-PVP nanoparticles were formed via self-assembling in aqueous media and composed of a hydrophobic alkyl core and a hydrophilic PVP outer shell. Their blood compatibility was evaluated by investigating their effect on red blood cells (RBCs) or erythrocytes, white blood cells (WBCs) or leukocytes, platelets (PLTs) and on complement system activation. Our results clearly demonstrate that the Amph-PVP nanoparticles are stable in presence of blood serum, have no significant effects on the function of RBCs, WBCs, PLTs and complement system activation. The Amph-PVP nanoparticles did not show considerable hemolytic or inflammatory effect, neither influence on platelet aggregation, coagulation process, or complement activation at the tested concentration range of 0.05-0.5â¯mg/ml. The Amph-PVP nanoparticles did not exhibit any significant effect on HMEC-1 microvascular skin endothelial cells' growth in in vitro experiments. The excellent blood compatibility of the Amph-PVP nanoparticles and the lack of effect on endothelium cell growth/viability represent a crucial feature dictating their further study as novel drug delivery systems.
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Materiales Biocompatibles , Plaquetas/efectos de los fármacos , Eritrocitos/efectos de los fármacos , Leucocitos/efectos de los fármacos , Nanopartículas/toxicidad , Pirrolidinonas/toxicidad , Línea Celular , Células Endoteliales/efectos de los fármacos , Endotelio Vascular/efectos de los fármacos , Humanos , Técnicas In Vitro , Nanopartículas/química , Pirrolidinonas/química , Piel/irrigación sanguínea , Piel/citologíaRESUMEN
Spirocyclic tetramic acids are widely used in controlling phytophagous mite species throughout the world. the data set is incomplete and provides insufficient evidence for drawing the same conclusion for fish. To fill the gap whether these acaricides alter lipid metabolism on vertebrates, zebrafish embryos exposed to a series concentration of pesticides, the developmental effects, enzyme activities and levels of gene expression were assessed, battery of biomarker utilized by the integrated biomarker response (IBRv2) model. The 96 h-LC50 of spirodiclofen, spiromesifen and spirotetramat were 0.14, 0.12 and 5.94â¯mg/L, respectively. Yolk sac deformity, pericardial edema, spinal curvature and tail malformation were observed. Three spirocyclic acids were unfavouring the lipid accumulation of by inhibited the acetyl-CoA carboxylase (ACC), fatty acid synthesis (FAS), fatty acid binding proteins (FABP2) and lipoprotein lipase (LPL) activity. The total cholesterol (TCHO) level significantly decreased in the 0.072â¯mg/L spirodiclofen group and 0.015 and 0.030â¯mg/L in the spiromesifen groups. No expected change in spirotetramat group on the TCHO and triglycerides (TGs) levels for any of the treatments. The mRNA levels of the genes related to lipid metabolism also significantly altered. In both spirodiclofen and spiromesifen, ACC achieved the highest scores among a battery of biomarkers using integrated biomarker response (IBRv2). The results suggest that spiromesifen was the most toxic for embryos development and spirodiclofen was the most toxic for lipid metabolism in embryos. The 0.07â¯mg/L of spirodiclofen, 0.05â¯mg/L of spiromesifen and 2.00â¯mg/L would cause malformation on zebrafish embryos. This study will provide new insight that fatty acid metabolism may be a suitable biomarker for the spirocyclic tetramic acids in fish species.
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Acaricidas/toxicidad , Embrión no Mamífero/efectos de los fármacos , Metabolismo de los Lípidos/efectos de los fármacos , Pirrolidinonas/toxicidad , Contaminantes Químicos del Agua/toxicidad , Pez Cebra/metabolismo , 4-Butirolactona/análogos & derivados , 4-Butirolactona/toxicidad , Animales , Compuestos Aza/toxicidad , Relación Dosis-Respuesta a Droga , Embrión no Mamífero/metabolismo , Proteínas de Unión a Ácidos Grasos/metabolismo , Compuestos de Espiro/toxicidad , Pruebas de Toxicidad , Proteínas de Pez Cebra/metabolismoRESUMEN
The toxicokinetics of N-ethyl-2-pyrrolidone (NEP), an embryotoxic organic solvent, has been studied in Sprague-Dawley rats after oral exposure. NEP and its metabolites 5-hydroxy-N-ethyl-2-pyrrolidone (5-HNEP) and 2-hydroxy-N-ethylsuccinimide (2-HESI) were measured in plasma of pregnant and non-pregnant rats, and fetuses after NEP administration by gavage for 14 consecutive days at 50 mg/kg/day, and in plasma of non-pregnant rats after a single NEP administration. Additionally, amniotic fluid and 24-h urine samples of the pregnant rats were analyzed for NEP metabolites. Furthermore, 24-h urine samples from a repeated dose 28-day oral toxicity study in female (non-pregnant) and male rats administered developmentally non-toxic (0, 5, and 50 mg/kg/day) or toxic (250 mg/kg/day) doses of NEP were analyzed. Median peak plasma concentrations in non-pregnant rats after a single dose and repeated doses were 551 and 611 (NEP), 182 and 158 (5-HNEP), and 63.8 and 108 µmol/L (2-HESI), respectively; whereas in pregnant rats and fetuses 653 and 619 (NEP), 80.5 and 91.7 (5-HNEP) and 77.3 and 45.7 µmol/L (2-HESI) were detected. Times to reach maximum plasma concentrations for NEP, 5-HNEP, and 2-HESI were 1, 4, and 8 h, respectively, and were comparable to N-methyl-2-pyrrolidone (NMP) and its corresponding metabolites. In pregnant rats, plasma elimination of NEP and metabolite formation/elimination was much slower compared to non-pregnant rats and efficient placental transfer of NEP was observed. Our data, overall, suggest differences in the toxicokinetics of chemicals between pregnant and non-pregnant rats which need to be addressed in risk assessment, specifically when assessing developmental toxicants such as NEP.
Asunto(s)
Líquido Amniótico/química , Sustancias Peligrosas , Placenta/metabolismo , Pirrolidinonas , Administración Oral , Animales , Relación Dosis-Respuesta a Droga , Femenino , Sustancias Peligrosas/sangre , Sustancias Peligrosas/toxicidad , Sustancias Peligrosas/orina , Masculino , Intercambio Materno-Fetal , Placenta/efectos de los fármacos , Embarazo , Pirrolidinonas/sangre , Pirrolidinonas/toxicidad , Pirrolidinonas/orina , Ratas Sprague-Dawley , ToxicocinéticaRESUMEN
A ninety-day toxicity and toxicokinetics of flurochloridone (FLC) were studied in male Wistar rats with oral administration at doses of 3 mg/kg and 10 mg/kg respectively, following the previous study. Apparent toxicity to reproductive system of male rats was still observed at the dose of 10 mg/kg, trace amounts of FLC were still detected 24 hours after administration, testicular weight, epididymal weight and serum testosterone were significantly reduced and sperm abnormalities in epididymis were significantly increased. No abnormalities were found in 3 mg/kg group, it indicated that no-observed-adverse-effect level (NOAEL) of FLC in male rats was 3 mg/kg/day, far below the dose of 20 mg/kg/day reported by European Food Safety Authority (EFSA). Therefore, more attention should be paid to this herbicide.
Asunto(s)
Relación Dosis-Respuesta a Droga , Nivel sin Efectos Adversos Observados , Tamaño de los Órganos/efectos de los fármacos , Pirrolidinonas/toxicidad , Testículo/efectos de los fármacos , Administración Oral , Animales , Femenino , Masculino , Ratas , Ratas Sprague-Dawley , Ratas Wistar , Pruebas de Toxicidad SubcrónicaRESUMEN
The wide use of Ag nanoparticles (Ag NPs) as antimicrobial agents has resulted in a massive release of Ag NPs into environment, such as water and soil. As bryophytes live ubiquitously in water and soil, their tolerance and response to Ag NPs could be employed as an indicator for the harm of Ag NPs to the environment. Herein, we report the study on the physiological and biochemical responses of bryophytes to Ag NPs with different surface coatings at the gametophyte stages: protonema and leafy gametophyte, by using Physcomitrella patens as a model system. We found that Ag NPs, including AgNPs-B (Ag NPs without surface coating), AgNPs-PVP (Ag NPs coated with poly (N-vinyl-2-pyrrolidone)) and AgNPs-Cit (Ag NPs coated with citrate), were toxic to P. patens in terms of growth and development of the gametophyte. The toxicity was closely related to the concentration and surface coating of Ag NPs, and the growth stage of P. patens. The protonema was more sensitive to Ag NPs than the leafy gametophyte. Ag NPs inhibited the growth of the protonema following the trend of AgNPs-Bâ¯>â¯AgNPs-Citâ¯>â¯AgNPs-PVP. Ag NPs changed the thylakoid and chlorophyll contents, but did not affect the contents of essential elements in the protonema. At the leafy gametophyte stage, Ag NPs inhibited the growth of P. patens following a different order: AgNPs-Citâ¯>â¯AgNPs-Bâ¯≈â¯AgNPs-PVP. Ag NPs decreased the chlorophyll b content and disturbed the balance of some important essential elements in the leafy gametophytes. Both the dissolved fraction of Ag NPs and Ag NPs per se contributed to the toxicity. This study for the first time reveals the effects of Ag NPs on bryophytes at different growth stages, which calls for more attention to the nanoecotoxicology of Ag NPs.
Asunto(s)
Bryopsida/efectos de los fármacos , Nanopartículas del Metal/toxicidad , Plata/toxicidad , Antiinfecciosos/química , Antiinfecciosos/toxicidad , Bryopsida/química , Clorofila/análisis , Ácido Cítrico/química , Nanopartículas del Metal/química , Metales Pesados/química , Metales Pesados/toxicidad , Desarrollo de la Planta/efectos de los fármacos , Pirrolidinonas/química , Pirrolidinonas/toxicidad , Plata/química , Pruebas de ToxicidadRESUMEN
There are reports of fluorochloridone (FLC)-induced male reproductive toxicity, but the underlying toxicological mechanisms remain unknown. In this study, we looked at how FLC exposure affected the integrity of the blood-testis barrier (BTB) and the Sertoli cell barrier and studied the molecular mechanisms. Male rats received gavage administration of FLC (30â¯mg/kg/d) for 14 consecutive days with sample collection at the 7th and 14th day; and primary cultured Sertoli cells were treated with 0-10⯵M FLC in vitro for 24â¯h. Our in vivo findings revealed that FLC exposure caused time-dependent testicular injuries, sperm quality decrease as well as adverse changes in BTB integrity, F-actin organization, and expressions of claudin-11 and Arp3. In Sertoli cells isolated from FLC-treated rat testis, Sertoli cell barrier tightness was increased. In Sertoli cells in vitro exposed to FLC, abnormal changes in the barrier permeability were also observed, and the protein expressions of occludin, claudin-11, ZO-1, connexin-43, and Arp3 were significantly decreased in a dose- and time-dependent manner. Furthermore, the FLC-induced adverse changes in Sertoli cell barrier and F-actin were partly alleviated by the induction of Arp3 overexpression. In conclusion, our findings revealed that FLC perturbed BTB/Sertoli cell barrier function through Arp3-mediated F-actin disorganization.
Asunto(s)
Citoesqueleto de Actina/efectos de los fármacos , Proteína 3 Relacionada con la Actina/metabolismo , Actinas/metabolismo , Contaminantes Ocupacionales del Aire/toxicidad , Barrera Hematotesticular/efectos de los fármacos , Pirrolidinonas/toxicidad , Reproducción/efectos de los fármacos , Células de Sertoli/efectos de los fármacos , Citoesqueleto de Actina/metabolismo , Citoesqueleto de Actina/patología , Proteína 3 Relacionada con la Actina/genética , Animales , Barrera Hematotesticular/metabolismo , Barrera Hematotesticular/patología , Células Cultivadas , Relación Dosis-Respuesta a Droga , Masculino , Permeabilidad , Ratas Sprague-Dawley , Medición de Riesgo , Células de Sertoli/metabolismo , Células de Sertoli/patología , Transducción de Señal/efectos de los fármacos , Proteínas de Uniones Estrechas/metabolismo , Uniones Estrechas/efectos de los fármacos , Uniones Estrechas/metabolismo , Uniones Estrechas/patología , Factores de TiempoRESUMEN
Fluorochloridone (FLC) is a widely used pyrrolidone selective herbicide and reported to induce testis injuries in male rats, but the underlying mechanism is largely unknown. In the present study, primary-cultured Sertoli cells were exposed to FLC at the concentration of 0-10.00µM to study the mechanism of FLC-induced apoptosis. The roles of ROS, intracellular calcium, endoplasmic reticulum (ER), and ERK1/2 were looked at with ROS scavenger N-acetyl-cysteine (NAC), intracellular calcium chelator BAPTA-AM, ER calcium depleting agent thapsigargin (TG), and ERK1/2 inhibitor U0126, respectively. FLC induced dose-dependent apoptosis increase as well as the elevation in levels of ROS, intracellular calcium, and ERK1/2 activation. FLC treatment led to constantly increasing apoptotic rates and ERK1/2 activation over time, while inversed-V shaped change tendencies of ROS and intracellular calcium levels were observed. FLC-induced ROS generation disrupted the intracellular calcium homeostasis by attacking the ER, and the elevated intracellular calcium levels resulted in ERK1/2 over-phosphorylation and consequently promoted Sertoli cell apoptosis. Taken together, ROS and intracellular calcium-mediated ERK1/2 activation led to FLC-induced Sertoli cell apoptosis.
Asunto(s)
Apoptosis/efectos de los fármacos , Señalización del Calcio/efectos de los fármacos , Herbicidas/toxicidad , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Pirrolidinonas/toxicidad , Especies Reactivas de Oxígeno/metabolismo , Células de Sertoli/efectos de los fármacos , Animales , Antioxidantes/farmacología , Quelantes del Calcio/farmacología , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Retículo Endoplásmico/efectos de los fármacos , Retículo Endoplásmico/enzimología , Retículo Endoplásmico/metabolismo , Activación Enzimática/efectos de los fármacos , Inhibidores Enzimáticos/farmacología , Hormesis , Masculino , Fosforilación/efectos de los fármacos , Inhibidores de Proteínas Quinasas/farmacología , Procesamiento Proteico-Postraduccional/efectos de los fármacos , Ratas Sprague-Dawley , ATPasas Transportadoras de Calcio del Retículo Sarcoplásmico/antagonistas & inhibidores , ATPasas Transportadoras de Calcio del Retículo Sarcoplásmico/metabolismo , Células de Sertoli/citologíaRESUMEN
Owing to the recent declines in honey bee (Apis mellifera L.) populations, there is a need for field and laboratory studies to investigate threats to pollinator health. This study examines the hypothesis that the organophosphate alternative, Rimon 0.83EC, can have consequences to honey bee health by combining newly acquired field residue data, laboratory bioassays, and colony level feeding studies. Following label rate applications of Rimon 0.83EC to apple trees, average residue concentrations of the active ingredient, novaluron, were found to be 3.38 ppm in tree-collected pollen. Residues of the major co-formulant in Rimon 0.83EC, N-methyl-2-pyrrolidone (NMP), were below the limit of detection in the field, but a growth chamber study described here found that NMP can persist in pollen for up to 7 d with average concentrations of 69.3 ppm. Concurrent larval rearing studies found novaluron and NMP to be toxic to developing honey bees at doses as low as 100 ppb and 100 ppm, respectively. Nucleus colony feeding studies found that chronic exposure to Rimon 0.83EC at doses as low as 200 ppm (18.6 ppm novaluron) can result in interruptions to brood production that can last for up to 2 wk after exposure. Taken together, these data indicate the use of Rimon 0.83EC on blooming flowers is a significant threat to honey bee reproduction, and suggest the need for more strict and clear usage guidelines.