The effect of Fe2O3 and ZnO nanoparticles on cytotoxicity and glucose metabolism in lung epithelial cells

Metallic nanoparticles (NPs) have potential applications in industry and medicine, but they also have the potential to cause many chronic pulmonary diseases. Mechanisms for their cytotoxicity, glucose and energy metabolism responses need to be fully explained in lung epithelial cells after treatment with metallic nanoparticles. In our study, two different metallic nanoparticles (Fe₂O₃ and ZnO) and two cell‐based assays (BEAS‐2B and A549 cell lines) were used. Our findings demonstrate that ZnO nanoparticles, but not Fe₂O₃ nanoparticles, induce cell cycle arrest, cell apoptosis, reactive oxygen species (ROS) production, mitochondrial dysfunction and glucose metabolism perturbation, which are responsible for cytotoxicity. These results also suggest that the glucose metabolism and bioenergetics had a great potential in evaluating the cytotoxicity and thus were very helpful in understanding their underlying molecular mechanisms. Copyright © 2015 John Wiley & Sons, Ltd.     

纳米二氧化硅致心肌线粒体损伤作用的研究

目的 研究纳米二氧化硅对心肌细胞线粒体的毒性作用及机制。方法 采用非暴露式气管内滴注的染 毒方式对 Balb/c 小鼠进行 3 种浓度（7、 21 和 35 mg/kg）粒径为 40 nm 左右的纳米二氧化硅暴露, 另设对照组滴注等 体积生理盐水。通过透射电子显微镜对小鼠心肌线粒体超微结构进行观察。通过对三磷酸腺苷 （ATP） 浓度的检测, 评价纳米二氧化硅对心肌线粒体功能的影响。通过对心肌组织抗 O2-·能力的检测, 评价心肌细胞线粒体抗氧化能 力。采用 Western blot 法对心肌组织中细胞色素 c 氧化酶 1 （COX1） 和琥珀酸脱氢酶 A （SDHA） 蛋白表达水平进行检 测, 从而阐明纳米二氧化硅对心肌细胞线粒体生物合成的影响。结果 与对照组相比, 高剂量的纳米二氧化硅可导 致线粒体结构的损伤, 主要表现为线粒体肿胀、 线粒体嵴排列紊乱甚至消失及线粒体融合。中、 高剂量的纳米二氧 化硅可导致心肌细胞线粒体功能下降。低、 中剂量的纳米二氧化硅可引起心脏组织抗 O2-·能力应激性升高, 而高剂 量的纳米二氧化硅则可导致心脏组织抗 O2-·能力下降。中剂量的纳米二氧化硅可应激性诱导线粒体的生物合成, 而 高剂量的纳米二氧化硅则抑制线粒体的生物合成。结论 高剂量的纳米二氧化硅可通过诱导线粒体内 O2-·的产生、 降低线粒体抗氧化能力, 从而导致线粒体结构和功能的损伤, 并抑制线粒体的生物合成。     

药用纳米SiO2对人正常肺细胞的氧化损伤

目的：探讨药用纳米SiO2对人正常肺细胞MRC-5的生长抑制与氧化损伤作用。方法：纳米SiO2暴露于MRC-5细胞48h后,以MTT法测定其对细胞增殖的影响,HE染色观察细胞的形态学变化,并检测暴露后细胞内活性氧（ROS）和还原型谷胱甘肽（GSH）含量以及超氧化物歧化酶（SOD）活性的改变,分析纳米材料对MRC-5细胞的氧化损伤作用。结果：两种尺度（粒径21.6、48.6nm）纳米SiO2暴露浓度分别达到0.4mg/mL与1.0mg/mL以上时,细胞存活率随暴露剂量的增加而降低,IC50分别为0.8mg/mL和1.9mg/mL。细胞形态皱缩,核质凝聚。细胞内活性氧明显升高（P〈0.01）,GSH含量和SOD活性显著降低（P〈0.05）,且呈现明显的剂量效应关系。结论：较高浓度纳米SiO2直接暴露可抑制人正常肺细胞MRC-5的增殖,其机理与细胞的氧化损伤有关。     

Iron oxide nanoparticles induced cytotoxicity,oxidative stress and DNA damage in lymphocytes

Over the past few decades nanotechnology and material science has progressed extremely rapidly. Iron oxide nanoparticles (IONPs) owing to their unique magnetic properties have a great potential for their biomedical and bioengineering applications. However, there is an inevitable need to address the issue of safety and health effects of these nanoparticles. Hence, the present study was aimed to assess the cytotoxic effects of IONPs on rats' lymphocytes. Using different assays, we studied diverse parameters including mitochondrial membrane potential, intracellular accumulation of reactive oxygen species (ROS), lactate dehydrogenase activity, antioxidant enzymes activity and DNA damage measurements. Intracellular metal uptake and ultrastructure analysis were also carried out through inductively coupled plasma atomic emission spectroscopy, transmission electron microscopy respectively. The results show that the IONP‐induced oxidative stress was concentration‐dependent in nature, with significant (P < 0.05) increase in ROS levels, lipid peroxidation level as well as depletion of antioxidant enzymes and glutathione. Moreover, we observed morphological changes in the cell after intracellular uptake and localization of nanoparticles in cells. From the findings of the study, it may be concluded that IONPs induce ROS‐mediated cytotoxicity in lymphocytes. Copyright © 2017 John Wiley & Sons, Ltd.     

A549细胞对壳寡糖及其纳米粒的摄取作用

目的研究壳寡糖及其纳米粒的A549肺上皮细胞摄取作用,探讨壳寡糖纳米粒作为药物载体的可能性。方法溶剂扩散法制备壳寡糖纳米粒,以A549肺上皮细胞评价壳寡糖及其纳米粒的细胞毒性,由荧光倒置显微镜、流式细胞仪研究A549细胞对壳寡糖及其纳米粒的摄取作用。结果壳寡糖及其纳米粒的细胞毒性均较低,IC₅₀分别为944.36和643.16 mg·L^-1。壳寡糖及其纳米粒的细胞摄取作用与其浓度及细胞孵育时间相关;在同一孵育时间壳寡糖纳米粒的摄取量比等浓度的壳寡糖增加0.49～13.9倍。结论壳寡糖及其纳米粒的细胞毒性较低。壳寡糖形成纳米粒后,可显著增加A549细胞的摄取作用。     

Cytotoxic effects of thioxanthone derivatives as photoinitiators on isolated rat hepatocytes

Thioxanthone and its analogues, 2- or 4-isopropylthioxanthone, 2-chlorothioxanthone , 2,4-diethylthioxanthone (DETX) and xanthone, are used as photoinitiators of ultraviolet (UV) light-initiated curable inks. As these photoinitiators were found in numerous food/beverage products packaged in cartons printed with UV-cured inks, the cytotoxic effects and mechanisms of these compounds were studied in freshly isolated rat hepatocytes. The toxicity of DETX was greater than that of other compounds. DETX elicited not only concentration (0–2.0 mm )- and time (0–3 hours)-dependent cell death accompanied by the depletion of cellular adenosine triphosphate (ATP), and reduced glutathione (GSH) and protein thiol levels, but also the accumulation of GSH disulfide and malondialdehyde. Pretreatment of hepatocytes with either fructose at a concentration of 10 mm or N-acetyl-l -cysteine (NAC) at a concentration of 5.0 mm ameliorated DETX (1 mm )-induced cytotoxicity. Further, the exposure of hepatocytes to DETX resulted in the induction of reactive oxygen species (ROS) and loss of mitochondrial membrane potential, both of which were partially prevented by the addition of NAC. These results indicate that: (1) DETX-induced cytotoxicity is linked to mitochondrial failure and depletion of cellular GSH; (2) insufficient cellular ATP levels derived from mitochondrial dysfunction were, at least in part, ameliorated by the addition of fructose; and (3) GSH loss and/or ROS formation was prevented by NAC. Taken collectively, these results suggest that the onset of toxic effects caused by DETX may be partially attributable to cellular energy stress as well as oxidative stress.     

Cellular uptake and toxicity effects of silver nanoparticles in mammalian kidney cells

The rapid progress and early commercial acceptance of silver‐based nanomaterials is owed to their biocidal activity. Besides embracing the antimicrobial potential of silver nanoparticles (AgNPs), it is imperative to give special attention to the potential adverse health effects of nanoparticles owing to prolonged exposure. Here, we report a detailed study on the in vitro interactions of citrate‐coated AgNPs with porcine kidney (Pk15) cells. As uncertainty remains whether biological/cellular responses to AgNPs are solely as a result of the release of silver ions or whether the AgNPs themselves have toxic effects, we investigated the effects of Ag⁺ on Pk15 cells for comparison. Next, we investigated the cellular uptake of both AgNPs and Ag⁺ in Pk15 cells at various concentrations applied. The detected Ag contents in cells exposed to 50 mg l^?1 AgNPs and 50 mg l^?1 Ag⁺ were 209 and 25 µg of Ag per 10⁶ cells, respectively. Transmission electron microscopy (TEM) images indicated that the Pk15 cells internalized AgNPs by endocytosis. Both forms of silver, nano and ionic, decreased the number of viable Pk15 cells after 24 h in a dose‐dependent manner. In spite of a significant uptake into the cells, AgNPs had only insignificant toxicity at concentrations lower than 25 mg l^?1, whereas Ag⁺ exhibited a significant decrease in cell viability at one‐fifth of this concentration. The Comet assay suggested that a rather high concentration of AgNP (above 25 mg l^?1) is able to induce genotoxicity in Pk15 cells. Further studies must seek deeper understanding of AgNP behavior in biological media and their interactions with cellular membranes. Copyright © 2014 John Wiley & Sons, Ltd.     

Toxic response of nickel nanoparticles in human lung epithelial A549 cells

Nickel nanoparticle (Ni NP) is increasingly used in modern industries such as catalysts, sensors and electronic applications. Due to wide-spread industrial applications the inhalation is the primary source of exposure to Ni NPs. However, data demonstrating the effect of Ni NPs on the pulmonary system remain scarce. The present study was designed to examine the toxic effect of human lung epithelial A549 cells treated with well characterized Ni NPs at the concentrations of 0, 1, 2, 5, 10 and 25 μg/ml for 24 and 48 h. Mitochondrial function (MTT assay), membrane leakage of lactate dehydrogenase (LDH assay), reduced glutathione (GSH), reactive oxygen species (ROS), membrane lipid peroxidation (LPO) and caspase-3 activity were assessed as toxicity end points. Results showed that Ni NPs reduced mitochondrial function and induced the leakage of LDH in dose and time-dependent manner. Ni NPs were also found to induce oxidative stress in dose and time-dependent manner indicated by depletion of GSH and induction of ROS and LPO. Further, activity of caspase-3 enzyme, marker of apoptosis was significantly higher in treated cells with time and Ni NPs dosage. The results exhibited significant toxicity of Ni NPs in human lung epithelial A549 cells which is likely to be mediated through oxidative stress. This study warrants more careful assessment of Ni NPs before their industrial applications.     

Impact of silver nanoparticles on human cells: Effect of particle size

Abstract

This work investigated the cytotoxicities of three silver nanoparticles (SNPs) SNP-5, SNP-20 and SNP-50 with different sizes (～ 5 nm, ～ 20 nm and ～ 50 nm) using four human cell models (A549, SGC-7901, HepG2 and MCF-7). Endpoints included cell morphology, cell viability, cellular membrane integrity, oxidative stress and cell cycle progression. Observable deleterious effects on the cell morphologies and membrane integrity were induced by SNP-5 and SNP-20. SNPs elevated the ROS levels in cells and arrested the cells at S phase. Apoptosis occurred for 4–9% of the exposed cells. All these cellular responses as well as EC50 values were found to be size-dependent for the tested SNPs. Ultrastructural observations confirmed the presence of SNPs inside cells. Elemental analysis of silver in cells by ICP-MS showed that smaller nanoparticles enter cells more easily than larger ones, which may be the cause of higher toxic effects. The findings may assist in the design of SNP applications and provide insights into their toxicity.     

Comparison of in vitro toxicity of silver ions and silver nanoparticles on human hepatoma cells

Scientific information on the potential harmful effects of silver nanoparticles (AgNPs) on human health severely lags behind their exponentially growing applications in consumer products. In assessing the toxic risk of AgNP usage, liver, as a detoxifying organ, is particularly important. The aim of this study was to explore the toxicity mechanisms of nano and ionic forms of silver on human hepatoblastoma (HepG2) cells. The results showed that silver ions and citrate‐coated AgNPs reduced cell viability in a dose‐dependent manner. The IC50 values of silver ions and citrate‐coated AgNPs were 0.5 and 50 mg L^?1, respectively. The LDH leakage and inhibition of albumin synthesis, along with decreased ALT activity, indicated that treatment with either AgNP or Ag ions resulted in membrane damage and reduced the cell function of human liver cells. Evaluation of oxidative stress markers demonstrating depletion of GSH, increased ROS production, and increased SOD activity, indicated that oxidative stress might contribute to the toxicity effects of nano and ionic forms of silver. The observed toxic effect of AgNP on HepG2 cells was substantially weaker than that caused by ionic silver, while the uptake of nano and ionic forms of silver by HepG2 cells was nearly the same. © 2014 Wiley Periodicals, Inc. Environ Toxicol 31: 679–692, 2016.     

Toxic effects of silver nanoparticles and nanowires on erythrocyte rheology

Rapid developments in the food applications of silver nanomaterials (Ag-NMs) have resulted in concerns related to the risk of overexposure of human blood. We investigated the effect of size and aspect ratio of Ag-NMs on rheological characteristics of human erythrocytes, including hemolysis, deformability, aggregation, and morphological changes. Red blood cells (RBCs) were exposed to two different sizes of spherical particles (d ∼ 30 nm or 100 nm) or nanowires (d ∼ 40 nm, l–2 μm in length) at a range of concentrations and incubation times. The concentrations of Ag-NMs were carefully chosen to avoid any hemorheological alteration due to hemolysis. Rheological properties were measured using microfluidic-laser diffractometry and aggregometry. RBC deformability apparently decreased after treatment with a low concentration of Ag-NPs for a short exposure time. However, RBC aggregation was significantly altered after treatment with a low concentration of either Ag-NWs or large Ag-NPs compared to small Ag-NPs. Additional experiments with Ag ions confirmed that the observed rheological changes were mainly caused by the Ag-NMs rather than the Ag ions. These hemorheological findings provide a better understanding of the interaction between RBCs and Ag-NMs and will help in assessing the risk of nanomaterial toxicity in blood.     

Comparative cytotoxicity of dolomite nanoparticles in human larynx HEp2 and liver HepG2 cells

Dolomite is a natural mineral of great industrial and commercial importance. With the advent of nanotechnology, natural minerals including dolomite in the form of nanoparticles (NPs) are being utilized in various applications to improve the quality of products. However, safety or toxicity information of dolomite NPs is largely lacking. This study evaluated the cytotoxicity of dolomite NPs in two widely used in vitro cell culture models: human airway epithelial (HEp2) and human liver (HepG2) cells. Concentration‐dependent decreased cell viability and damaged cell membrane integrity revealed the cytotoxicity of dolomite NPs. We further observed that dolomite NPs induce oxidative stress in a concentration‐dependent manner, as indicated by depletion of glutathione and induction of reactive oxygen species (ROS) and lipid peroxidation. Quantitative real‐time PCR data demonstrated that the mRNA level of tumor suppressor gene p53 and apoptotic genes (bax, CASP3 and CASP9) were up‐regulated whereas the anti‐apoptotic gene bcl‐2 was down‐regulated in HEp2 and HepG2 cells exposed to dolomite NPs. Moreover, the activity of apoptotic enzymes (caspase‐3 and caspase‐9) was also higher in both kinds of cells treated with dolomite NPs. It is also worth mentioning that HEp2 cells seem to be marginally more susceptible to dolomite NPs exposure than HepG2 cells. Cytotoxicity induced by dolomite NPs was efficiently prevented by N‐acetyl cysteine treatment, which suggests that oxidative stress is primarily responsible for the cytotoxicity of dolomite NPs in both HEp2 and HepG2 cells. Toxicity mechanisms of dolomite NPs warrant further investigations at the in vivo level. Copyright © 2015 John Wiley & Sons, Ltd.     

Toxicological effects of three types of silver nanoparticles and their salt precursors acting on human U-937 and HL-60 cells

The growing popularity of nanomaterials requires a systematic study of their effects on the human body. Silver nanoparticles (AgNPs), due to their antiseptic properties, are used in almost every area of life. The purpose of the study was to examine whether the precursor used for the synthesis of nanoparticles affects their bio-influence and modifies their impact on cells of the human immune system. To compare the effects of precursor silver salts (AgNO₃, CH₃COOAg and AgClO₄) and corresponding nanoparticles (TAN TAA and TAC) cytotoxicity study was conducted on two cell lines U-937 and HL-60. For both cell lines, silver salts are more toxic than the corresponding nanoparticles. Cell viability after treatment with the two forms of silver (salt/particle) is dependent on silver dose and degree of cells differentiation. Addition of the silver salt of doses greater than 5?mg/L results in decreased cell viability by over 60%, whereas nanoparticles’ addition reduces cell viability on average by 30%. On the basis of the determined LD₅₀ values it can be stated that for the tested cells the most toxic are AgClO₄ and TAC. Production of nitric oxide, which is a mediator of inflammation, is the greatest after treatment of the cells by TAC. Different interactions of studied nanoparticles with albumin has been found and it was shown that addition of albumin to the cells treated by nanoparticles reduces their toxic effects. Obtained by us highly purified, mono-disperse AgNPs exhibit diverse effects relative to the biological systems, depending on the precursor salt used.     

Influence of the surface coating on the cytotoxicity,genotoxicity and uptake of gold nanoparticles in human HepG2 cells

The toxicological profile of gold nanoparticles (AuNPs) remains controversial. Significant efforts to develop surface coatings to improve biocompatibility have been carried out. In vivo biodistribution studies have shown that the liver is a target for AuNPs accumulation. Therefore, we investigated the effects induced by ~20 nm spherical AuNPs (0–200 μM Au) with two surface coatings, citrate (Cit) compared with 11‐mercaptoundecanoic acid (11‐MUA), in human liver HepG2 cells. Cytotoxicity was evaluated using the 3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyltetrazolium bromide (MTT) reduction and lactate dehydrogenase (LDH) release assays after 24 to 72 h of incubation. DNA damage was assessed by the comet assay, 24 h after incubation with the capped AuNPs. Uptake and subcellular distribution of the tested AuNPs was evaluated by quantifying the gold intracellular content by graphite furnace atomic absorption spectrometry (GFAAS) and transmission electron microscopy (TEM), respectively. The obtained results indicate that both differently coated AuNPs did not induce significant cytotoxicity. An inverse concentration‐dependent increase in comet tail intensity and tail moment was observed in Cit‐AuNPs‐ but not in MUA‐AuNPs‐exposed cells. Both AuNPs were internalized in a concentration‐dependent manner. However, no differences were found in the extent of the internalization between the two types of NPs. Electron‐dense deposits of agglomerates of Cit‐ and MUA‐AuNPs were observed either inside endosomes or in the intercellular spaces. In spite of the absence of cytotoxicity, DNA damage was observed after exposure to the lower concentrations of Cit‐ but not to MUA‐AuNPs. Thus, our data supports the importance of the surface properties to increase the biocompatibility and safety of AuNPs. Copyright © 2013 John Wiley & Sons, Ltd.     

Comparative study of ZnO and TiO2 nanoparticles: physicochemical characterisation and toxicological effects on human colon carcinoma cells

Abstract

Despite human gastrointestinal exposure to nanoparticles (NPs), data on NPs toxicity in intestinal cells are quite scanty. In this study we evaluated the toxicity induced by zinc oxide (ZnO) and titanium dioxide (TiO₂) NPs on Caco-2 cells. Only ZnO NPs produced significant cytotoxicity, evaluated by two different assays. The presence of foetal calf serum in culture medium significantly reduced ZnO NPs toxicity as well as ion leakage and NP-cell interaction. The two NPs increased the intracellular amount of reactive oxygen species (ROS) after 6 h treatment. However, only ZnO NPs increased ROS and induced IL-8 release both after 6 and 24 h. Experimental data indicate a main role of chemical composition and solubility in ZnO NPs toxicity. Moreover our results suggest a key role of oxidative stress in ZnO NPs cytotoxicity induction related both to ion leakage and to cell interaction with NPs in serum-free medium.     

Proteomic analysis of zearalenone toxicity on mouse thymic epithelial cells

Zearalenone (ZEA) is one of the most major food contaminants in cereal crops worldwide, risking health of both livestock and humans. This study aimed to assess the cytotoxicity and the underlying mechanism of ZEA on thymic epithelial cells. By using proteomics analysis, we identified 596 differentially expressed proteins in MTEC1 cells upon zearalenone exposure, of which 245 were upregulated and 351 were downregulated. Gene ontology (GO) analysis suggested that differentially expressed proteins were participated in protein synthesis, oxidative phosphorylation, and ATP binding. KEGG pathway enrichment analysis showed that differentially expressed proteins were mainly related to mitochndrial metabolism, such as citrate cycle (TCA cycle) and oxidative phosphorylation. We demonstrated that ZEA treatment was able to increase the intracellular reactive oxygen species (ROS) level, to decrease ΔΨm, ATP level, and the copy number of mtDNA, leading to necrotic cell death. Moreover, we showed that ZEA treatment inhibited cell proliferation and induced G2/M phase arrest by downregulation of proliferation-associated proteins ERK, p-ERK, CDK1, and p-CHK1. Taken together, we found that the toxicity of ZEA on thymic epithelial cells is mainly caused by the inhibition of mitochondrial dysfunction and cell proliferation. Our study might open new avenues for treatment strategies.     

ZnO nanoparticles induced inflammatory response and genotoxicity in human blood cells: A mechanistic approach

The wide application of zinc oxide nanoparticles (ZnO NPs) in cosmetics, paints, biosensors, drug delivery, food packaging and as anticancerous agents has increased the risk of human exposure to these NPs. Earlier in vitro and in vivo studies have demonstrated a cytotoxic and genotoxic potential of ZnO NPs. However, there is paucity of data regarding their immunomodulatory effects. Therefore, the present study was aimed to investigate the immunotoxic potential of ZnO NPs using human monocytic cell line (THP-1) as model to understand the underlying molecular mechanism. A significant (p < 0.01) increase in pro-inflammatory cytokines (TNF-α and IL-1β) and reactive oxygen species (ROS) was observed with a concomitant concentration dependent (0.5, 1, 5, 10, 15 and 20 μg/mL) decrease in the glutathione (GSH) levels as compared to control. The expression levels of mitogen activated protein kinase (MAPK) cascade proteins such as p-ERK1/2, p-p38 and p-JNK were also significantly (p < 0.05, p < 0.01) induced. Also, at the concentration tested, NPs induced DNA damage as assessed by the Comet and micronucleus assays. Our data demonstrated that ZnO NPs induce oxidative and nitrosative stress in human monocytes, leading to increased inflammatory response via activation of redox sensitive NF-κB and MAPK signalling pathways.