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In this study, the interaction mechanism and native conformational variation of trypsin (Try) affected by CeO2 nanoparticles (NPs) were systematically studied via various spectroscopic methods. The results of fluorescence spectroscopy revealed that CeO2 NPs markedly quenched the endogenous fluorescence of Try via the mechanism of static quenching. The main forces that contributed to the binding of Try and CeO2 NPs were van der Waals forces, hydrogen bonds, and electrostatic forces, as observed by the binding constants and significant thermodynamic characteristics of the two substances. The incorporation of CeO2 NPs lead to a slight change in the structure of Try, as shown by synchronized fluorescence spectroscopy, three-dimensional fluorescence spectroscopy and circular dichroism (CD) spectroscopy. Moreover, the enzyme activity of Try decreased with the addition of CeO2 NPs. This study is highly important for fully evaluating the use of CeO2 NPs in biomedical sciences and is helpful for clarifying the mechanism between Try and CeO2 NPs at the molecular level.

RESUMEN

General anesthetics exposure, particularly prolonged or repeated exposure, is a crucial cause of neurological injuries. Notably, isoflurane (ISO), used in pediatric anesthesia practice, is toxic to the developing brain. The relatively weak antioxidant system at early ages needs antioxidant support to protect the brain against anesthesia. Cerium oxide nanoparticles (CeO2-NPs, nanoceria) are nano-antioxidants and stand out due to their unique surface chemistry, high stability, and biocompatibility. Although CeO2-NPs have been shown to exhibit neuroprotective and cognitive function-facilitating effects, there are no reports on their protective effects against anesthesia-induced neurotoxicity and cognitive impairments. Herein, Wistar albino rat pups were exposed to ISO (1.5 %, 3-h) at postnatal day (P)7+P9+P11, and the protective properties of CeO2-NP pretreatment (0.5 mg/kg, intraperitoneal route) were investigated for the first time. The control group at P7+9+11 received 50 % O2 (3-h) instead of ISO. Exposure to nanoceria one-hour before ISO protected hippocampal neurons of the developing rat brain against apoptosis [determined by hematoxylin-eosin (HE) staining, immunohistochemistry (IHC) analysis with caspase-3, and immunoblotting with Bax/Bcl2, cleaved caspase-3 and PARP1] oxidative stress, and inflammation [determined by immunoblotting with 4-hydroxynonenal (4HNE), nuclear factor kappa-B (NF-κB), and tumor necrosis factor-alpha (TNF-α)]. CeO2-NP pretreatment also reduced ISO-induced learning (at P28-32) and memory (at P33) deficits evaluated by Morris Water Maze. However, memory deficits and thigmotactic behaviors were detected in the agent-control group; elimination of these harmful effects will be possible with dose studies, thus providing evidence supporting safer use. Overall, our findings support pretreatment with nanoceria application as a simple strategy that might be used for pediatric anesthesia practice to protect infants and children from ISO-induced cell death and learning and memory deficits.

RESUMEN

The frequency, duration, and intensity of heat waves (HWs) within terrestrial ecosystems are increasing, posing potential risks to agricultural production. Cerium dioxide nanoparticles (CeO2 NPs) are garnering increasing attention in the field of agriculture because of their potential to enhance photosynthesis and improve stress tolerance. In the present study, CeO2 NPs decreased the grain yield, grain protein content, and amino acid content by 16.2, 23.9, and 10.4%, respectively, under HW conditions. Individually, neither the CeO2 NPs nor HWs alone negatively affected rice production or triggered stomatal closure. However, under HW conditions, CeO2 NPs decreased the stomatal conductance and net photosynthetic rate by 67.6 and 33.5%, respectively. Moreover, stomatal closure in the presence of HWs and CeO2 NPs triggered reactive oxygen species (ROS) accumulation (increased by 32.3-57.1%), resulting in chloroplast distortion and reduced photosystem II activity (decreased by 9.4-36.4%). Metabolic, transcriptomic, and quantitative real-time polymerase chain reaction (qRT-PCR) analyses revealed that, under HW conditions, CeO2 NPs activated a stomatal closure pathway mediated by abscisic acid (ABA) and ROS by regulating gene expression (PP2C, NCED4, HPCA1, and RBOHD were upregulated, while CYP707A and ALMT9 were downregulated) and metabolite levels (the content of γ-aminobutyric acid (GABA) increased while that of gallic acid decreased). These findings elucidate the mechanism underlying the yield and nutritional losses induced by stomatal closure in the presence of CeO2 NPs and HWs and thus highlight the potential threat posed by CeO2 NPs to rice production during HWs.

Asunto(s)

Cerio , Calor , Nanopartículas , Oryza , Estomas de Plantas , Oryza/metabolismo , Oryza/efectos de los fármacos , Oryza/crecimiento & desarrollo , Cerio/química , Cerio/farmacología , Estomas de Plantas/metabolismo , Estomas de Plantas/efectos de los fármacos , Nanopartículas/química , Especies Reactivas de Oxígeno/metabolismo , Fotosíntesis/efectos de los fármacos

RESUMEN

In this study, the interaction effects of NaAsO2 (1 and 5 µM), SiO2 NPs (10 and 100 mg/L) and CeO2 NPs (10 and 100 mg/L) were assessed in Vigna mungo (Blackgram). The treatment of NaAsO2, SiO2, CeO2-NPs and combinations of NPs & As were applied to blackgram plants under hydroponic conditions. After its application, the morpho-physiological, antioxidant activity, and phytochemical study were evaluated. At 10 and 100 mg/L of SiO2 and CeO2-NPs, there was an increase in antioxidative enzymatic activity (p < 0.05) and reactive oxygen species (ROS). However, substantial ROS accumulation was observed at 1 and 5 µM NaAsO2 and 100 mg/L SiO2 NPs (p < 0.05). Additionally, at such concentrations, there is a substantial reduction in photosynthetic pigments, nitrogen fixation, chlorosis, and plant development when compared to controls (p < 0.05). The combination of SiO2 and CeO2 NPs (10 and 100 mg/L) with NaAsO2 decreased superoxide radical and hydrogen peroxide and improved SOD, CAT, APX, GR, and chlorophyll pigments (p < 0.05). Further FTIR results were evaluated for documenting elemental and phytochemical analysis.

Asunto(s)

Arsénico , Cerio , Nanopartículas , Dióxido de Silicio , Vigna , Dióxido de Silicio/química , Vigna/efectos de los fármacos , Cerio/química , Nanopartículas/química , Antioxidantes , Especies Reactivas de Oxígeno/metabolismo

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INTRODUCTION: Green synthesis offers a fast, simple, and economical method for producing metallic nanoparticles.The basis of this method is to obtain nanoparticles using natural materials, such as plants, fungi, and bacteria, instead of harmful and expensive chemical-reducing agents. In this study, CeO2NPs were produced using Alhagi maurorum extract, and their anticancer and antibacterial activities were evaluated. METHODS: Alhagi maurorum extract was prepared according to a previously described protocol, and CeO2NPs were synthesized from the salt of this extract. The resulting nanoparticles were characterized using Transmission electron microscopy (TEM), scanning electron microscope (SEM), and X-ray diffraction (XRD) techniques. The antibacterial and cytotoxic effects of the nanoparticles were measured by MIC, MBC, and MTT assays, respectively. The results were analyzed using one-way analysis of variance (ANOVA) using Prism software. RESULTS: The MTT assay on breast cancer cell lines showed that the cytotoxic effect of CeO2NPs on cell lines was concentration-dependent. In addition, this nanoparticle was more effective against Gram-positive bacteria. CONCLUSION: These nanoparticles can be used as cancer drug delivery systems with specific targeting at low concentrations in addition to anticancer treatments. It can also have biological and medicinal applications, such as natural food preservation and wound dressing.

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Antibacterianos , Neoplasias de la Mama , Cerio , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Pruebas de Sensibilidad Microbiana , Extractos Vegetales , Hojas de la Planta , Humanos , Cerio/química , Cerio/farmacología , Antibacterianos/farmacología , Antibacterianos/química , Antibacterianos/síntesis química , Hojas de la Planta/química , Extractos Vegetales/farmacología , Extractos Vegetales/química , Extractos Vegetales/aislamiento & purificación , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/patología , Proliferación Celular/efectos de los fármacos , Nanopartículas/química , Nanopartículas del Metal/química , Antineoplásicos Fitogénicos/farmacología , Antineoplásicos Fitogénicos/química , Antineoplásicos Fitogénicos/síntesis química , Antineoplásicos Fitogénicos/aislamiento & purificación , Relación Estructura-Actividad , Antineoplásicos/farmacología , Antineoplásicos/química , Antineoplásicos/síntesis química , Supervivencia Celular/efectos de los fármacos , Femenino , Bacterias Grampositivas/efectos de los fármacos , Línea Celular Tumoral , Tamaño de la Partícula

RESUMEN

Nanozymes with core@shell nanostructure are considered promising biolabeling materials for their multifunctional properties. In this work, a simple one-pot strategy has been proposed for scalable synthesis of gold@cerium dioxide core@shell nanoparticles (Au@CeO2 NPs) with strong localized surface plasmon resonance (LSPR) absorption and high peroxidase-like catalytic activity by redox reactions of Ce3+ ions and AuCl4- ions in diluted ammonia solution under room temperature. A colorimetric lateral flow immunochromatographic assay (LFIA) has been successfully fabricated for sensitive detection of heart-type fatty acid binding protein (H-FABP, an early cardiac biomarker) by using the Au@CeO2 NPs as reporters. The as-developed LFIA with Au@CeO2 NP reporter (termed as Au@CeO2-LFIA) exhibits a dynamic range of nearly two orders of magnitude, and a limit of detection (LOD) as low as 0.35 ng mL-1 H-FABP with nanozyme-triggered 3,3',5,5'-tetramethylbenzidine (TMB) colorimetric amplification. Furthermore, the practicality of Au@CeO2-LFIA has been demonstrated by profiling the concentrations of H-FABP in 156 blood samples of acute myocardial infarction (AMI) patients, and satisfactory results are obtained.

Asunto(s)

Colorimetría , Nanopartículas del Metal , Humanos , Colorimetría/métodos , Proteína 3 de Unión a Ácidos Grasos , Peroxidasa/química , Inmunoensayo/métodos , Iones , Oro/química , Nanopartículas del Metal/química

RESUMEN

A novel carbon catalyst was created based on plant metallurgy strategy for organic pollutants removal. Plants rich in CeO2 NPs in water were used as carbon precursors and pyrolyzed with urea to obtain Ce/N co-doped carbon catalysts, which were used in the degradation of sulfamethoxazole (SMX) by active peroxymonosulfate (PMS). The results showed that the Ce/N @BC/PMS system achieved to 94.5% degradation of SMX in 40 min at a rate constant of 0.0602 cm-1. The activation center of PMS is widely dispersed Ce oxide nanocrystals, and CeO2 NPs promote the formation of oxygen centered PFR with enhanced catalytic ability and longer half-life. In addition, N-doping facilitates the transfer of π-electrons within the sp2 carbon of biochar, increasing active sites and thus improving PMS activation efficiency. The degradation process was contributed to by both radical and non-radical activation mechanisms including 1O2 and direct electron transfer, with O2•- serving as 1O2's precursor. Through the DFT calculations, LC-MS and toxicological analyses, the degradation pathway of pollutants and the toxicity changes throughout the entire degradation process were further revealed, indicating that the degradation of SMX could effectively reduce ecological toxicity.

Asunto(s)

Contaminantes Ambientales , Sulfametoxazol , Sulfametoxazol/química , Peróxidos/química , Oxígeno

RESUMEN

This work presents the effect of CeO2 nanoparticles (CeO2-NPs) on Cu-50Ni-5Al alloys on morphological, microstructural, degradation, and electrochemical behavior at high temperatures. The samples obtained by mechanical alloying and spark plasma sintering were exposed to a molten eutectic mixture of Li2CO3-K2CO3 for 504 h. The degradation of the materials was analyzed using gravimetry measurements and electrochemical impedance spectroscopy. Different characterization techniques, such as X-ray diffraction and scanning electron microscopy, were used to investigate the phase composition, parameter lattice, and microstructure of Cu-Ni-Al alloys reinforced with CeO2-NPs. The hardness of the composite was also examined using the Vickers hardness test. Gravimetry measurements revealed that the sample with 1 wt.% CeO2-NPs presented the best response to degradation with a less drastic mass variation. Impedance analysis also revealed that by adding 1 wt.% CeO2-NPs, the impedance modulus increased, which is related to a lower porosity of the oxide film or a thicker oxide layer. The microhardness also significantly increased, incorporating 1 wt.% CeO2-NPs, which reduced with higher CeO2-NPs content, which is possibly associated with a more uniform distribution using 1 wt.% CeO2-NPs in the Cu-Ni-Al matrix that avoided the aggregation phenomenon.

RESUMEN

BACKGROUND: Chlorpyrifos (CPF) is a widely used insecticide that causes toxicity to living organisms through the production of free radicals. Cerium oxide nanoparticles (CeO2NPs) are a new antioxidant agent that has proved therapeutic effects. We evaluated the effect of CeO2NPs on CPF hepatotoxicity. METHODS: Forty rats were randomized into four groups. Group I: rats received 1 ml corn oil by gastric tube once daily and 0.5 ml PBS by intra-peritoneal injection twice a week for 4 weeks. Group II: received CeO2NPs 0.5 mg/kg in PBS by i.p. injection, twice weekly for four weeks. Group III: were treated with oral administration of CPF 13.5 mg/kg in corn oil daily for 4 weeks. Group IV: received CPF as in group III, then each animal received CeO2NPs twice weekly for four weeks as in group II. Twenty-four hours after the last dose, rats were anesthetized and sera were collected for liver enzymes assessment. Afterwards, rats were sacrificed, livers were excised, the right lobe of each liver was fixed for immunohistochemical studies, and the left lobe was homogenized for oxidative profile assessment and molecular analysis. RESULTS: CPF group showed significant increase in liver transaminases, disturbance of the oxidative profile with up-regulation of BAX expression and down-regulation in the Bcl-2, Gadd45 and NFE2L2. CPF caused severe histopathological liver damage as well as significant increase in anti-Caspase 3 and TNF immunostaining. The CeO2NPs treated group revealed significant improvement of all previous parameters. CONCLUSION: CeO2NPs could alleviate CPF hepatoxicity through decreasing expression of the inflammatory and apoptotic proteins and increasing the activity of antioxidant enzymes.

Asunto(s)

Enfermedad Hepática Inducida por Sustancias y Drogas , Cloropirifos , Nanopartículas , Ratas , Animales , Cloropirifos/toxicidad , Antioxidantes/farmacología , Aceite de Maíz/farmacología , Estrés Oxidativo , Nanopartículas/uso terapéutico , Enfermedad Hepática Inducida por Sustancias y Drogas/tratamiento farmacológico

RESUMEN

In recent times, significant attention has been directed toward the synthesis and application of nanoparticles (NPs) in agriculture sector. In current study, nanoceria (CeO2 NPs) synthesized by green method were employed to address cadmium (Cd) accumulation in wheat (Triticum aestivum L.) cultivated in field with excess Cd. The application of CeO2 NPs was carried out through foliar spraying, performed twice during the growth of T. aestivum. Four levels of CeO2 NPs were used: T0, T1, T2, and T3 as 0, 50, 75, and 100 mgL-1, respectively. Results highlighted the positive effects of CeO2 NPs on various growth parameters, including plant height, spike length, photosynthetic related attributes, as well as straw and grain of grains in comparison to T1 (control group). Furthermore, CeO2 NPs led to a reduction in oxidative stress in the leaves and enhanced in enzyme activities in comparison to T1. Notably, Cd concentrations in straw, roots, and grains exhibited a decline following the treatment with CeO2 NPs, in contrast to the control group. In terms of health implications, the calculated health risk index associated with dietary consumption of grains by adults remained below the defined threshold with supply of nanoparticles. Foliar application of CeO2 NPs proved to be an effective approach in reducing cadmium content in wheat grains. This reduction holds significant potential for minimizing the risk of cadmium exposure to human health through the food chain. Employing the green synthesis method amplifies the potential for extensive production and a wide array of environmental applications for CeO2 NPs. This dual capacity makes them proficient in tackling environmental stresses while concurrently mitigating adverse ecological effects.

Asunto(s)

Cadmio , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos , Adulto , Humanos , Triticum , Transporte Biológico , Dieta

RESUMEN

Sodium alginate based (SA) hydrogel supplemented Cerium Oxide nanoparticles (CeO2NPs) was produced to fabricate an antimicrobial thin film using an aqueous extract of G. salicornia (Gs). The Gs-CeO2NPs were characterized via SEM, FT-IR, EDX, XRD and DLS, the particle size was 200 nm, agreed with XRD. Gs-SA powder was extracted and incorporated with CeO2NPs. The Gs-SA and its composite thin film (Gs-CeO2NPs-SATF) were characterized including viscosity, FT-IR, TGA, and SEM. The adhesion of Gs-SA coating around Gs-CeO2NPs confirmed via FTIR. The antimicrobial properties of Gs-CeO2NPs and CeO2NPs-SATF were proved in MICs for E. coli and Candida albicans at 62.5 and 250.0 µg/mL. The biofilm inhibition efficiency of CeO2NPs-SATF was 74.67 ± 0.98% and 65.45 ± 0.40% for E. coli and Candida albicans. The CeO2NPs-SATF was polydisperse in nature and film structure gets fluctuated with NPs concentration. Increased NPs into SATF enhances pore size of gel and corroborated with viscous behaviour. The cytotoxicity of Gs-CeO2NP-SA in Artemia salina at higher concentration 100 µg/mL provides less lethal effect into the adult. The antioxidant activity of Gs-CeO2NP-SA in DPPH assay was noticed at 0.6 mg ml-1 with radical scavenging activity at 65.85 ± 0.81%. Thus the Gs-CeO2NP-SATF would be suitable in antimicrobial applications.

Asunto(s)

Antiinfecciosos , Gracilaria , Nanopartículas del Metal , Nanopartículas , Hidrogeles , Escherichia coli , Espectroscopía Infrarroja por Transformada de Fourier , Antiinfecciosos/farmacología , Nanopartículas/química

RESUMEN

BACKGROUND: In a significant proportion of cancers, point mutations of TP53 gene occur within the DNA-binding domain, resulting in an abundance of mutant p53 proteins (mutp53) within cells, which possess tumor-promoting properties. A potential and straightforward strategy for addressing p53-mutated cancer involves the induction of autophagy or proteasomal degradation. Based on the previously reported findings, elevating oxidative state in the mutp53 cells represented a feasible approach for targeting mutp53. However, the nanoparticles previous reported lacked sufficient specificity of regulating ROS in tumor cells, consequently resulted in unfavorable toxicity in healthy cells. RESULTS: We here in showed that cerium oxide CeO2 nanoparticles (CeO2 NPs) exhibited an remarkable elevated level of ROS production in tumor cells, as compared to healthy cells, demonstrating that the unique property of CeO2 NPs in cancer cells provided a feasible solution to mutp53 degradation. CeO2 NPs elicited K48 ubiquitination-dependent degradation of wide-spectrum mutp53 proteins in a manner that was dependent on both the dissociation of mutp53 from the heat shock proteins Hsp90/70 and the increasing production of ROS. As expected, degradation of mutp53 by CeO2 NPs abrogated mutp53-manifested gain-of-function (GOF), leading to a reduction in cell proliferation and migration, and dramatically improved the therapeutic efficacy in a BxPC-3 mutp53 tumor model. CONCLUSIONS: Overall, CeO2 NPs increasing ROS specifically in the mutp53 cancer cells displayed a specific therapeutic efficacy in mutp53 cancer and offered an effective solution to address the challenges posed by mutp53 degradation, as demonstrated in our present study.

Asunto(s)

Cerio , Nanopartículas , Neoplasias Pancreáticas , Humanos , Proteína p53 Supresora de Tumor/genética , Proteína p53 Supresora de Tumor/metabolismo , Genes p53 , Línea Celular Tumoral , Proteínas Mutantes/genética , Proteínas Mutantes/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Neoplasias Pancreáticas/tratamiento farmacológico , Neoplasias Pancreáticas/genética

RESUMEN

BACKGROUND: The biological effects of cerium dioxide nanoparticles (CeO2NPs), a novel material in the biomedical field, have attracted widespread attention. Our previous study confirmed that exposure to CeO2NPs during pregnancy led to abnormal trophoblast invasion during early placental development, thereby impairing placental development. The potential mechanisms may be related to low-quality decidualization triggered by CeO2NPs exposure, such as an imbalance in trophoblast invasion regulators secreted by decidual cells. However, the intermediate link mediating the "dialogue" between decidual cells and trophoblasts during this process remains unclear. As an important connection between cells, exosomes participate in the "dialogue" between endometrial cells and trophoblasts. Exosomes transfer bioactive microRNA into target cells, which can target and regulate the level of mRNA in target cells. RESULTS: Here, we constructed a mice primary uterine stromal cell-induced decidualization model in vitro, and detected the effect of CeO2NPs exposure on the expression of decidual-derived exosomal miRNAs by high-throughput sequencing. Bioinformatics analysis and dual-luciferase reporter assays were performed to identify target genes of the screened key miRNAs in regulating trophoblast invasion. Finally, the role of the screened miRNAs and their target genes in regulating trophoblast (HTR-8/SVneo cells) invasion was confirmed. The results showed that CeO2NPs exposure inhibited trophoblast invasion by promoting miR-99a-5p expression in decidual-derived exosomes, and Ppp2r5a is a potential target gene for miR-99a-5p to inhibit trophoblast invasion. CONCLUSIONS: This study revealed the molecular mechanism by which CeO2NPs exposure inhibits trophoblast invasion from the perspective of decidual derived exosomal miRNAs. These results will provide an experimental basis for screening potential therapeutic targets for the negative biological effects of CeO2NPs exposure and new ideas for studying the mechanism of damage to trophoblast cells at the decidual-foetal interface by harmful environmental or occupational factors.

Asunto(s)

MicroARNs , Trofoblastos , Animales , Ratones , Embarazo , Femenino , Trofoblastos/metabolismo , Placenta/metabolismo , MicroARNs/genética , MicroARNs/metabolismo , Movimiento Celular , Proliferación Celular

RESUMEN

In this study, soil-grown pakchoi after 2 weeks seedling cultivation were exposed to CeO2 nanoparticles (CeO2 NPs) at 0.7, 7, 70, and 350 mg kg-1 for 30 days. Results showed that chlorophyll content and photosynthetic assimilation rate were decreased significantly under all treatments with the largest decrease of 34.16% (0.7 mg kg-1 CeO2 NPs), however, sub-stomatal CO2 was increased dramatically under low dose of CeO2 NPs (0.7 mg kg-1). There were 4576, 3548, 2787, and 2514 genes up/down regulated significantly by 0.7, 7, 70, and 350 mg kg-1 CeO2 NPs, respectively, and 767 genes affected under all treatments. In addition, 0.7 mg kg-1 CeO2 NPs up-regulated 10 chlorophyll synthesis genes, 20 photosynthesis genes, and 10 carbon fixation enzyme genes; while 350 mg kg-1 CeO2 NPs down-regulated 5 photosynthesis genes and 28 auxin-activated genes. Among the key genes of photosynthesis, Ferredoxin-NADP reductase (PetH) was upregulated in 0.7, 7 and 70 mg kg-1 treatments, while Photosystem II lipoprotein (Psb27) was downregulated under 7, 70 and 350 mg kg-1 treatments. Top 20 metabolic pathways affected by CeO2 NPs including plant hormone, amino acids, and glutathione, and carbon metabolism These results provide information about utilizing CeO2 NPs more safely and effectively in the future.

Asunto(s)

Brassica , Nanopartículas , Transcriptoma , Fotosíntesis , Nanopartículas/toxicidad , Clorofila

RESUMEN

Objective To investigate the effects of CeO2 NP subacute exposure on body weight,organ structures,and redox indicators in male mice.Methods Thirty-five male ICR mice were randomly divided into five groups with seven mice in each group.Normal control and CeO2 NP(100,500,1000 and 5000 μg/kg)groups were included.Mice were injected with CeO2 NPs intraperitoneally every other day for 28 days.Results Compared with the control group,no significant difference was found in weight gain(P>0.05),but significant differences were observed in the liver coefficient,epididymal coefficient,and sperm survival rate(P<0.01).In the 5000 μg/kg group,CeO2 NPs were deposited in the liver and spleen,and granuloma was found SOD and GSH-Px activities in serum of the 100 μg/kg group were increased,while MDA content was decreased,which indicated the antioxidant effect of CeO2 NPs.With the increase in dose,oxidative stress induced by CeO2 NPs was enhanced.Conclusions Low-dose-CeO2 NPs are safe and exert an antioxidant effect.With the increase in dose,the toxicity of CeO2 NPs also increases gradually.

RESUMEN

Soil salinization is a common environmental problem that seriously threatens crop yield and food security, especially through its impact on seed germination. Nanoparticle priming, an emerging seed treatment method, is receiving increasing attention in improving crop yield and stress resistance. This study used alfalfa seeds as materials to explore the potential benefits of cerium oxide nanoparticle (CeO2NP) priming to promote seed germination and improve salt tolerance. CeO2NPs at concentrations up to 500 mg/L were able to significantly alleviate salt stress in alfalfa seeds (200 mM), with 50 mg/L of CeO2NP having the best effect, significantly (P< 0.05) increasing germination potential (from 4.0% to 51.3%), germination rate (from 10.0% to 62.7%), root length (from 8.3 cm to 23.1 cm), and seedling length (from 9.8 cm to 13.7 cm). Priming treatment significantly (P< 0.05) increased seed water absorption by removing seed hardness and also reducing abscisic acid and jasmonic acid contents to relieve seed dormancy. CeO2NP priming increased α-amylase activity and osmoregulatory substance level, decreased reactive oxygen species and malonaldehyde contents and relative conductivity, and increased catalase enzyme activity. Seed priming regulated carotenoid, zeatin, and plant hormone signal transduction pathways, among other metabolic pathways, while CeO2NP priming additionally promoted the enrichment of α-linolenic acid and diterpenoid hormone metabolic pathways under salt stress. In addition, CeO2NPs enhanced α-amylase activity (by 6.55%) in vitro. The optimal tested concentration (50 mg/L) of CeO2NPs was able to improve the seed vigor, enhance the activity of α-amylase, regulate the osmotic level and endogenous hormone levels, and improve the salt tolerance of alfalfa seeds. This study demonstrates the efficacy of a simple seed treatment strategy that can improve crop stress resistance, which is of great importance for reducing agricultural costs and promoting sustainable agricultural development.

RESUMEN

Introduction: Kochiae Fructus has been widely used in Chinese Herbal medicine to treat various diseases. We report a rapid and eco-friendly approach for cerium oxide (CeO2) nanoparticles (NPs) synthesis using the extract of medicinally important plant "Kochiae Fructus", and the synthesized NPs were named KF-CeO2 NPs. Methods: Various spectroscopic approaches such as transmission electron microscope (TEM), powder X-ray diffraction (XRD), and energy-dispersive X-Ray (EDX) were used to characterize the KF-CeO2 NPs effectively. The antibacterial and biofilm inhibition activity of KF-CeO2 NPs against Gram-positive and Gram-negative multi-drug resistant (MDR) bacteria was determined using the serial dilution method and XTT assay. KF-CeO2 NPs were assessed for anticancer activity against HeLa cancer cells using an MTT assay. Cytobiocompatibility was determined in two normal cell lines (3T3 and hMSC). Results and Discussion: The average size of the KF-CeO2 NPs was 11.3 ± 3.9 nm with spherical morphology. KF-CeO2 NPs demonstrated a greater than 95% bactericidal efficacy against MDR microorganisms. In addition, KF-CeO2 NPs strongly suppressed (more than 79%) the biofilms of MDR bacteria, indicating their potential for addressing antibiotic resistance issues. Compared to Kochiae Fructus extract and CH-CeO2 NPs, they exhibited significant cytotoxic effects (35.60% cell viability) on HeLa cancer cells. In addition, the KF-CeO2 NPs were shown to be highly biocompatible with hMSC and 3T3 cell lines (85.13% and 81.17% cell viability, respectively), suggesting that they may be employed in biological systems. Conclusion: These data indicate that KF-CeO2 NPs synthesized using Kochiae Fructus extract are promising alternative treatments for MDR. In addition, this study will give the potential for the sustained development of biocompatible NPs with enhanced biological capabilities derived from vital pharmaceutical plants.

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Extractos Vegetales , Extractos Vegetales/farmacología

RESUMEN

Nanoparticles have a promising future in biomedical applications and knowing whether they affect ex vivo vascular reactivity is a necessary step before their use in patients. In this study, we have evaluated the vascular effect of cerium dioxide nanoparticles (CeO2NPs) on the human saphenous vein in response to relaxing and contractile agonists. In addition, we have measured the protein expression of key enzymes related to vascular homeostasis and oxidative stress. We found that CeO2NPs increased expression of both SOD isoforms, and the consequent reduction of superoxide anion would enhance the bioavailability of NO explaining the increased vascular sensitivity to sodium nitroprusside in the presence of CeO2NPs. The NOX4 reduction induced by CeO2NPs may lead to lower H2O2 synthesis associated with vasodilation through potassium channels explaining the lower vasodilation to bradykinin. In addition, we showed for the first time, that CeO2NPs increase the expression of ACE2 in human saphenous vein, and it may be the cause of the reduced contraction to angiotensin II. Moreover, we ruled out that CeO2NPs have effect on the protein expression of eNOS, sGC, BKca channels and angiotensin II receptors or modify the vascular response to noradrenaline, endothelin-1 and TXA2 analogue. In conclusion, CeO2NPs show antioxidant properties, and together with their vascular effect, they could be postulated as adjuvants for the treatment of cardiovascular diseases.

Asunto(s)

Nanopartículas , Vena Safena , Humanos , Antioxidantes/farmacología , Angiotensina II , Peróxido de Hidrógeno

RESUMEN

For environmental preservation, it is crucial to effectively remove organic waste from water. Several approaches have been put forth, but photocatalysis stands out as a quick and effective solution. In this study, some hybrid polymeric structures that were created by photopolymerizing cellulose acetate/castor oil urethane methacrylates with embedded CeO2 nanoparticles (NPs) and in situ photogenerated noble metal nanoparticles (Ag, Au, Pd) are characterized, and photochemically thoroughly evaluated. The effective modification of cellulose acetate with urethane methacrylate sequences and the degree of functionalization were first observed using 1H NMR and FTIR spectra. Additionally, scanning and transmission electron microscopy, X-ray diffraction, FT-IR and UV-visible spectroscopy were utilized to analyse the resultant nanocomposites. The homogeneous dispersion of CeO2 NPs (10-40 nm) into an organic matrix with the suitable functionalities, namely urethane and hydroxyl groups, favour the interfacial charge transfer reducing the Eg up to 2.85 eV. Moreover, noble metal nanoparticles (5-15 nm), such as Ag, Au and Pd introduction in nanocomposites, significantly lowered the Eg: 2.1 eV for CeAg samples, 1.7 eV for CeAu films and 1.5 eV for CePd films, respectively. This opens up new avenues for the creation of flexible cellulose-based photocatalysts that are active in visible light.

Asunto(s)

Nanopartículas del Metal , Espectroscopía Infrarroja por Transformada de Fourier , Nanopartículas del Metal/química , Luz , Celulosa/química , Uretano

RESUMEN

Background: Cerium dioxide nanoparticles (CeO2 NPs) are increasingly used as diesel additive, causing a lot of concern about their toxic effects when released into the atmosphere. To date, there is little knowledge about the toxic effects of CeO2 NPs on the female reproductive system. Methods: The morphology and size distribution of CeO2 NPs was observed by transmission electronic microscope (TEM) and Zetasizer Nano, respectively. The uptake of CeO2 NPs by cells was also observed by TEM after treatment. The cytotoxicity of CeO2 NPs was studied by Cell Counting Kit-8 (CCK-8), the cellular invasive and migratory ability was examined by transwell assay, the cell apoptosis and reactive oxygen species (ROS) were studied by flow cytometry (FCM), and the mRNAs and proteins expressions were revealed by quantitative real-time PCR (qRT-PCR) and western blotting. The cytoskeletons and autophagy levels were revealed by immunofluorescence. The target regulation of miR-99 to mammalian target of rapamycin (mTOR) was proved by dual luciferase reporter assay after transfection. Results: We studied the cytotoxic effects of CeO2 NPs on human trophoblastic cells (HTR-8/Svneo) and found that the invasive and migratory abilities of HTR-8/SVneo cells were decreased after CeO2 NPs exposure. Immunofluorescence assays showed that the cellular microtubule networks and microfilament arrangement were obviously altered, and although the expression of cytoskeleton proteins (α-tubulin, ß-tubulin, actin) did not change, the protein levels of invasion- and migration-related factors [matrix metalloproteinase 2 (MMP2), protein kinases B (AKT), mTOR] were decreased in exposed cells. Accordingly, the expression level of miR-99 family members (miR-99a, miR-99b, miR-100), which can regulate mTOR, was significantly increased after CeO2 NPs exposure. Dual luciferase reporter assay indicated that the miR-99 family members directly targeted mTOR. Conclusions: CeO2 NPs impaired the invasive and migratory abilities, which play an important role in embryo implantation, as well as determining placental function and embryonic development.