Differential cytotoxicity of copper ferrite nanoparticles in different human cells

Argyreia nervosa-driven biosynthesis of Cu-Ag bimetallic nanoparticles from plant leaves extract unveils enhanced antibacterial properties

Our study specifically explores the biosynthesis of copper-silver bimetallic nanoparticles (Cu-Ag BMNPs) using Argyreia nervosa (AN) plant leaf green extract as a versatile agent for capping, reducing, and stabilizing. This biosynthesis method is characterized by its simplicity and cost-effectiveness, utilizing silver nitrate (AgNO3) and cupric oxide (CuO) as precursor materials. Our comprehensive characterization of the Cu-Ag BMNPs, employing techniques such as X-ray diffraction (XRD), UV-Vis spectrometry, scanning electron microscopy (SEM), Zetasizer, and Fourier transformed infrared spectrometry (FTIR). FTIR analysis reveals biofunctional groups and chemical bands, while SEM and XRD analyses provide morphological and structural details. To evaluate the antimicrobial properties of the Cu-Ag BMNPs, we conducted disc diffusion and minimum inhibitory concentration (MIC) assays against Escherichia coli (E. coli), with results compared to the standard gentamicin antibiotic. It is observed that the 2% and 5% CuO concentrations of AN Cu-Ag BMNPs exhibit substantial antibacterial activity in comparison to AN extract when tested on EPEC. Among these, the Cu-Ag BMNPs at a 2% concentration demonstrate higher antibacterial activity, potentially attributed to the enhanced dispersion of BMNPs facilitated by the lower CuO doping concentration. These two assays showcased the improved antimicrobial activity of Cu-Ag BMNPs, highlighting their synergistic effect, characterized by high MIC values and a broad zone of inhibition in the disc diffusion tests against E. coli. These results emphasize the significant antibacterial potential of the synthesized BMNPs, with a medicinal plant AN leaf extract playing a pivotal role in enhancing antibacterial activity.

Investigating the biocompatibility, flexural strength, and surface roughness of denture base resin containing copper oxide nanoparticles: An in vitro study

Aim

This study aimed to evaluate the biocompatibility, flexural strength, and surface roughness of polymethyl methacrylate (PMMA) containing Copper Oxide Nanoparticles (CuO NPs) at different concentrations.

Methods

25 heat-polymerized PMMA wax patterns fabricated in 5 groups containing 0.5, 5, 50, and 500 μg/ml CuO NPs and nanoparticle (NP)-free PMMA discs were prepared. 5 growth mediums (DMEM with 10% FBS and 1% penicillin-streptomycin) without disks were also incubated similarly to serve as the control groups. The cytotoxicity of the discs was measured by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assay on cultured Human Gingival Fibroblasts. The number of 1.3 × 104 cells were seeded in each well of 96-well plates (5 wells for the extract of each specimen). Days 1, 3, 5, and 7 were the intervals that the culture media were in direct contact with the PMMA discs for either 24 or 72 h. After that, a total of 40 specimens with 65 × 10 × 2.5 mm dimensions were prepared in five groups (n = 8). The specimens were subjected to a rugosimeter for the evaluation of surface roughness. The flexural strength test was performed using a universal testing machine. Microscopic evaluation was performed for the dispersion of the NPs. Non-parametric Kruskal-Wallis test and parametric one-way ANOVA test were used for data analysis.

Results

The samples containing 500 μg/ml NPs showed the lowest percentage of cell viability at all incubation periods, while the highest cell viability was observed in NP-free PMMA 24 h after the seventh day of incubation. NPs at 50 and 500 μg/ml concentrations showed strongly significant differences in cytotoxicity compared to the 0 concentration and the control group (p < 0.001). Although all the samples demonstrated an increasing pattern of cell viability on the third, fifth, and seventh days, the percentage of cell viability was significantly lower after 72 h than after 24 h in all incubation periods (p < 0.001). NPs significantly increased flexural strength (p = 0.005) but did not affect the surface roughness of the PMMA discs (p = 0.396).

Significance

The CuO NPs were cytotoxic only when applied in high concentrations, but presented a descending trend over time. No cytotoxic effect was observed in the experimental groups after seven days of incubation. Furthermore, CuO NPs increased flexural strength, but the surface roughness of the PMMA discs was not affected.

Fabrication and biological investigation of a novel star polymer based on magnetic cyclic aromatic polyimide chains

Herein, a novel nanostructure based on cyclic aromatic polyimide with statistical star polymer structure was synthesized via the functionalization of the CuFe₂O₄ MNPs surface. The polymerization process on the functionalized surface of CuFe₂O₄ MNPs was performed with pyromellitic dianhydride and phenylenediamine derivatives. All analytical methods such as Fourier-transform infrared (FT-IR) spectroscopy, thermogravimetric (TG) analysis, X-ray diffraction (XRD) pattern, energy-dispersive X-ray (EDX), field-emission scanning electron microscope (FE-SEM), vibrating-sample magnetometer (VSM) were performed to characterize the structure of CuFe₂O₄@SiO₂-polymer nanomagnetic. The cytotoxicity of CuFe₂O₄@SiO₂-Polymer was investigated for biomedical application by MTT test. The results proved that this nanocmposite was biocompatible with HEK293T healthy cells. Also, the evaluation antibacterial property of CuFe₂O₄@SiO₂-Polymer showed that its MIC in Gram-negative and Gram-positive bacteria were 500-1000 µg/mL, so it had antibacterial activity.

Khalaf AA, R. Zaki A, Mansour Khalifa M, A. Ibrahim M, M. Mekkawy A, E. Abdelrahman R, Farghali A, A. Noshy P. Hesperidin protects rats’ liver and kidney from oxidative damage and physiological disruption induced by nickel oxide nanoparticles

Background: Nickel oxide nanoparticles (NiO-NPs) have recently been utilized in various advanced industrial fields like lithium-ion micro batteries, nanofibers, electrochromic devices, and several biomedical applications. NiO-NPs are classified as extremely toxic substances as they can cause long-term harm to the environment and aquatic life. Moreover, frequent and prolonged exposure can affect human and animal health, causing skin allergies and major toxic consequences, such as hepatorenal toxicity. Hesperidin (HSP) has been proven to possess anti-inflammatory, antioxidant, and free radical scavenging activities.

Objective: This study aimed to investigate the underlying protective mechanisms and effects of HSP against NiO-NPs-induced hepatorenal toxicities in rats.

Materials and Methods: Forty male Wistar rats were randomly divided into four groups (n = 10 in each). The first group served as a Control group. For 8 weeks, the second group was administered NiO-NPs (100 mg/kg/day), and the third group was given HSP (100 mg/kg/day) via oral gavage for both groups. The fourth group received NiO-NPs and HSP concurrently in the same oral daily doses and duration as the second and third groups.

Results: NiO-NPs administration revealed a significant increase in plasma biomarkers of nephrotoxicity (urea, creatinine) and hepatotoxicity (ALT, AST) in NiO-NPs group compared to Control group (p < 0.05). In addition, NiO-NPs administration resulted in a substantial increase in malondialdehyde levels with a significant drop in catalase activity and GSH content in Group II. Also, a significant decreased expression of Nrf-2 and Bcl-2 mRNA levels and upregulation of TNF-α, NF-kβ and BAX in the liver and kidney of NiO-NPs group were also detected. Histologically, the liver and kidney of rats of NiO-NPs group showed significant histopathological disturbances, with a substantial increase in the proliferating cell nuclear antigen (PCNA) positive hepatocytes and renal tubular cells in the NiO-NPs group compared to Control and HSP groups (p < 0.05). In contrast, concomitant administration of HSP with NiO-NPs in group IV showed a significant biochemical, histopathological, and immunohistochemical improvement compared to NiO-NPs group.

Conclusion: Co-administration of HSP with NiO-NPs significantly ameliorated most of the NiO-NPs-induced hepatorenal toxicities in male rats.

Neodymium oxide nanostructures and their cytotoxic evaluation in human cancer cells

Neodymium oxide exhibits a unique property, which facilitates and largely utilized as an industrial applications. A number of cytotoxic study is available but very limited information is available to understand their biological activity with neodymium oxide at a very low conc- entration of the material. The present work was designed to understand the cytotoxicity against liver (HepG-2) and lung (A-549) cancer cells. Initially, Neodymium oxides (Nd₂O₃) were prepared and characterized with various instruments. The crystallinity and morphology of Nd₂O₃ powder were examined with instruments such as X-Ray Diffraction (XRD), scanning electron microscope (SEM), Transmission electron microscopy (TEM), Energy Dispersive X-Ray Analysis (EDX) respectively, revealed the size of curved nanostructure are ~140 ± 2 in diameter whereas length goes upto ~700 nm with elemental composition. The cytotoxicity study was conducted with MTT, NRU assay with genotoxicity study via ROS, cell cycle and qPCR analysis. The cells cytotoxic assessment were analysed via MTT(3-(4,5-Dimethylthiazol-2-yl)- 2,5-Diphenyl tetra zolium Bromide) and Neutral Red Uptake (NRU) assay with neodymium oxide (Nd₂O₃), which indicates the reduction in cell viability. Additionally, cell-cycle analysis showed an increase in the apoptotic peak after a 24-h. Quantitative real-time PCR (RT-PCR) data revealed that apoptotic genes such as p53, bax, and caspase-3 were up regulated, whereas bcl-2, an anti-apoptotic gene, was down regulated; therefore, apoptosis was mediated through ROS and genotoxicity pathways. The experiments of cytotoxicity was tested and concludes that the Nd₂O₃ express a moderate and dose dependent effect on cancer cells. The ROS, cell cycle analysis and qPCR showed that Nd₂O₃ exhibit the capability to cells death via ROS generation and genotoxicity study pathways.

Biosynthesis of Zn-doped CuFe2O4 nanoparticles and their cytotoxic activity

Zn-doped CuFe2O4 nanoparticles (NPs) were eco-friendly synthesized using plant extract. These nanoparticles were characterized by X-ray diffraction, Fourier-transform infrared spectroscopy, scanning electron microscope (SEM), energy-dispersive X-ray spectroscopy and thermal gravimetric analysis (TGA). SEM image showed spherical NPs with size range less than 30 nm. In the EDS diagram, the elements of zinc, copper, iron, and oxygen are shown. The cytotoxicity and anticancer properties of Zn-doped CuFe2O4 NPs were evaluated on macrophage normal cells and A549 lung cancer cells. The cytotoxic effects of Zn-doped CuFe2O4 and CuFe2O4 NPs on A549 cancer cell lines were analyzed. The Zn-doped CuFe2O4 and CuFe2O4 NPs demonstrated IC50 values 95.8 and 278.4 µg/mL on A549 cancer cell, respectively. Additionally, Zn-doped CuFe2O4 and CuFe2O4 NPs had IC80 values of 8.31 and 16.1 µg/mL on A549 cancer cell, respectively. Notably, doping Zn on CuFe2O4 NPs displayed better cytotoxic effects on A549 cancer cells compared with the CuFe2O4 NPs alone. Also spinel nanocrystals of Zn-doped CuFe2O4 (~ 13 nm) had a minimum toxicity (CC50 = 136.6 µg/mL) on macrophages J774 Cell Line.

Strontium-Doped Nickel Oxide Nanoparticles: Synthesis, Characterization, and Cytotoxicity Study in Human Lung Cancer A549 Cells

In this manuscript, the grown and annealed strontium-doped nickel oxide nanoparticles (SrNiONPs) were synthesized using a precipitation method with nickel nitrate and strontium nitrate as precursor agents with trisodium citrate. Various characterization techniques, including X-ray diffraction pattern (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), UV-visible, and zeta sizer, were used to thoroughly examine the samples. The XRD pattern (21 nm) was used to calculate the size, phases, and crystallinity of the material (SrNiONPs). In addition to characterization, the material was tested for cytotoxicity in lung cancer cells (A549). The viability test in A549 cells was performed using [3-(4, 5-dimethylthiazol-2-yl)-2, 5 diphenyltetrazolium bromide] (MTT) and Neutral Red Uptake (NRU) assay with SrNiONPs concentration ranging from 1 to 100 μg/mL. According to the MTT and NRU data, the toxicity studies are dose-dependent. SrNiONPs also increased reactive oxygen species (ROS) and were involved in apoptosis (A549 cells). Furthermore, quantitative PCR (qPCR) data revealed that the mRNA levels of apoptotic genes marker like p53, bax, and caspase-3 were upregulated, whereas bcl-2, an anti-apoptotic gene, was downregulated. As a result, apoptosis was mediated by the p53, bax, caspase3, and bcl-2 pathways, implying a potential mechanism by which SrNiONPs mediate their toxicity.

Copper ferrite nanoparticles induced cytotoxicity and oxidative stress in Channel catfish ovary cells

Nanomaterials are the sixth most emerging contaminants that are entering into aquatic habitat posing a risk to the inhabiting organisms. Nanoparticles of copper ferrite have been extensively used in biomedical applications. However, very limited studies are available on the cytotoxicity evaluation of copper ferrite nanoparticles (CuFe₂O₄NPs) on different cell lines. The current work investigates on the cytotoxicity, oxidative stress and morphological variations triggered by CuFe₂O₄NPs in Channel catfish ovary (CCO) cells using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazoliumbromide (MTT), neutral red uptake (NRU), lipid peroxidation (LPO), catalase (CAT), reduced glutathione (GSH), glutathione sulfotransferase (GST) and glutathione peroxidase (GPX) assays after 24 h of treatment. Dose dependent decline in cell survival was noticed in MTT and NRU assays. A significant increase in LPO, GST and GPX was observed in CCO cells exposed to CuFe₂O₄NPs after 24 h of treatment. However, the CAT and GSH levels in CCO cells exposed to CuFe₂O₄NPs decreased significantly after 24 h. The CCO cells exposed to 10 μg/mL concentration of CuFe₂O₄NPs for 24 h showed remarkable changes in their morphology. Further, the study also describes the detailed mechanism of toxicity of CuFe₂O₄NPs in other model cell lines to probe the risk of inhabiting organisms.

Characterization of toxicological effects of complex nano-sized metal particles using in vitro human cell and whole blood model systems

Metal oxide fumes form at high temperatures, for instance, during welding or firing ammunition. Inhalation exposure to high levels of airborne metal oxide particles can cause metal fume fever, cardiovascular effects, and lung damage in humans, but the associated underlying pathological mechanisms are still not fully understood. Using human alveolar epithelial cells, vascular endothelial cells, and whole blood model systems, we aimed to elucidate the short-term effects of well-characterized metal particles emitted while firing pistol ammunition. Human lung epithelial cells exposed to gunshot smoke particles (0.1-50 μg/ml) produced reactive oxygen species (ROS) and pro-inflammatory cytokines (interleukin 8 (IL-8), granulocyte-macrophage colony-stimulating factor (GM-CSF)) that activate and recruit immune cells. Particles comprising high copper (Cu) and zinc (Zn) content activated human endothelial cells via a non-ROS-mediated mechanism that triggered immune activation (IL-8, GM-CSF), leukocyte adhesion to the endothelium (soluble intercellular adhesion molecule 1 (sICAM-1)), and secretion of regulators of the acute-phase protein synthesis (interleukin 6 (IL-6)). In human whole blood, metal oxides in gunshot smoke demonstrated intrinsic properties that activated platelets (release of soluble cluster of differentiation 40 ligand (sCD40L), platelet-derived growth factor B-chain homodimer(PDGF-BB), and vascular endothelial growth factor A (VEGF-A)) and blood coagulation and induced concomitant release of pro-inflammatory cytokines from blood leukocytes that further orchestrate thrombogenesis. The model systems applied provide useful tools for health risk assessment of particle exposures, but more studies are needed to further elucidate the mechanisms of metal fume fever and to evaluate the potential risk of long-term cardiovascular diseases.

Reduced graphene oxide mitigates cadmium-induced cytotoxicity and oxidative stress in HepG2 cells

Numerous applications of reduced graphene oxide (RGO) and pervasive cadmium (Cd) have led concern about their co-exposure to the environment and human. We studied the combined effects of RGO and Cd in human liver (HepG2) cells. Initially, we found that RGO (up to 50 μg/ml) did not harm to HepG2 cells while Cd induced dose-dependent (1-10 μg/ml) cytotoxicity. Exciting observations were that a non-cytotoxic concentration of RGO (25 μg/ml) effectively mitigates the toxic effects of Cd (2 μg/ml) such as cell viability reduction, lactate dehydrogenase release, and irregular cell morphology. Cd-induced cell cycle arrest, induction of caspases (3 and 9) enzymes activity, and loss of mitochondrial membrane potential were also significantly alleviated by RGO co-exposure. Moreover, generation of pro-oxidants (reactive oxygen species and hydrogen peroxide levels) and depletion of antioxidants (glutathione level and superoxide dismutase activity) due to Cd exposure was effectively attenuated by RGO co-exposure. Mitigating effect of RGO could be due to strong adsorption of Cd on the large surface area of RGO sheets, which decrease the cellular uptake and bioavailability of Cd for HepG2 cells. This study warrants future research on potential mechanisms of mitigating effects of RGO against Cd-induced toxicity in animal models.

Intraperitoneal injections of copper ferrite nanoparticles disturb blood, plasma, and antioxidant parameters of Wistar rats in a sex-specific manner

The present study was designed to report the synthesis and characterization of copper ferrite nanoparticles (CF NPs) and their biocompatibility in Wistar rats. Coprecipitation method was used to generate CF NPs having average diameter of 14.06 nm. NPs were characterized by scanning electron microscopy and X-ray diffraction. Six-week-old Wistar rats of both sexes intraperitoneally received 10 mg/ml saline/Kg body weight of CF NPs for 14 days. Control groups were maintained in parallel that received saline solution for 14 days through same route. Open field and novel object recognition tests, complete blood count, selected plasma parameters, antioxidants, and copper concentration in vital organs were determined in all treatments. Female rats treated with CF NPs had significantly higher platelet count (P = 0.05) and platelet crit (P = 0.05) and decreased plasma triglyceride concentration levels (P = 0.02) than control group. Female rats had significantly increased levels of superoxide dismutase (P = 0.01), catalase (P = 0.05), and malonaldehyde (P = 0.05) in the kidney, while male rats had significantly elevated levels of superoxide dismutase in the lungs (P = 0.01) as compared with respective control groups. Copper concentrations in the liver were significantly higher in both female (P = 0.04) and male (P = 0.05) rats exposed to CF NPs than control group. All other studied parameters of behavioral tests, blood biochemistry, antioxidant, and copper concentrations in the brain varied nonsignificantly (P > 0.05) when compared between CF NPs treated and untreated rats of both sexes. Intraperitoneal supplementation of CF NPs for 14 days disturbed the platelet count, plasma triglyceride concentration, copper levels in the liver, and antioxidant concentrations in the kidney of female Wistar rats. These parameters remained unaffected in male subjects.

Cytotoxicity of NiO and Ni(OH)2 Nanoparticles Is Mediated by Oxidative Stress-Induced Cell Death and Suppression of Cell Proliferation

The use of nanomaterial-based products continues to grow with advancing technology. Understanding the potential toxicity of nanoparticles (NPs) is important to ensure that products containing them do not impose harmful effects to human or environmental health. In this study, we evaluated the comparative cytotoxicity between nickel oxide (NiO) and nickel hydroxide (Ni(OH)₂) in human bronchoalveolar carcinoma (A549) and human hepatocellular carcinoma (HepG2) cell lines. Cellular viability studies revealed cell line-specific cytotoxicity in which nickel NPs were toxic to A549 cells but relatively nontoxic to HepG2 cells. Time-, concentration-, and particle-specific cytotoxicity was observed in A549 cells. NP-induced oxidative stress triggered dissipation of mitochondrial membrane potential and induction of caspase-3 enzyme activity. The subsequent apoptotic events led to reduction in cell number. In addition to cell death, suppression of cell proliferation played an essential role in regulating cell number. Collectively, the observed cell viability is a function of cell death and suppression of proliferation. Physical and chemical properties of NPs such as total surface area and metal dissolution are in agreement with the observed differential cytotoxicity. Understanding the properties of NPs is essential in informing the design of safer materials.

The antimicrobial and cytotoxic effects of a copper-loaded zinc oxide phosphate cement

Objectives

Evidence about modifications of dental luting materials to minimize biological failure at the “marginal gap” between teeth and fixed prosthodontics is scarce. We compared a copper-modified (Co-ZOP) and a conventional zinc oxide phosphate cement (ZOP) in terms of antimicrobial and cytotoxic potentials in vitro and in vivo.

Materials and methods

Specimens of ZOP and Co-ZOP were characterized by the mean arithmetic roughness (Ra) and surface free energy (SFE). Powder components were examined using scanning electron microscopy (SEM). Energy-dispersive X-ray spectroscopy (EDX) showed elemental material compositions. In vitro microbial adhesion was shown using SEM, luminescence, and fluorescence assays. CCK-8 assays of mouse fibroblasts (L929) and human gingival fibroblasts (GF-1) were performed after 6, 24, and 48 h of specimen incubation. In vivo, ZOP and Co-ZOP specimens were applied intraorally for 12 h; biofilm accumulation was shown using SEM.

Results

Ra of ZOP and Co-ZOP showed no significant differences; SFE was significantly higher for Co-ZOP. EDX exhibited minor copper radiation for Co-ZOP, none for ZOP. In vitro fungal adhesion to Co-ZOP was significantly higher than to ZOP; in vitro streptococcal adhesion, cytotoxicity, and in vivo biofilm formation were not significantly different.

Conclusions

Co-ZOP showed low surface allocations of copper with no improved antimicrobial properties compared with conventional ZOP in vitro or in vivo.

Clinical relevance

Antimicrobial effects and low cytotoxicity of biomaterials are important for the clinical outcome. Based on our in vitro and in vivo results, no clinical recommendation can be given for the tested Co-ZOP.

Spinel ferrite nanoparticles and nanocomposites for biomedical applications and their toxicity

This review focuses on the biomedical applications and toxicity of spinel ferrite nanoparticles (SFNPs) with more emphasis on the recently published work. A critical review is provided on recent advances of SFNPs applications in biomedical areas. The novelty of SFNPs in addressing the bottleneck problems encountered in the areas of health; in particular, for diagnosis and treatment of tumour cells are well reviewed. Furthermore, research gaps, toxicity of SFNPs and areas which still need more attention are highlighted. Based on the result of this review, the SFNPs have unlimited capacity in cancer treatment, disease diagnosis, magnetic resonance imaging, drug delivery and release. Overall, stepping out of the conventional way of treatment is difficult but also essential in bringing long lasting solution for cancer and other diseases treatment. In fact, the toxicity study and commercialisation of the SFNPs based cancer treatment options are the main challenges and need further study, in order to reduce unforeseen consequences.

The pro-inflammatory stimulus of zinc- and copper-containing welding fumes in whole blood assay via protein tyrosine phosphatase 1B inhibition

An asymptomatic systemic inflammation after exposure to zinc- and copper-containing welding fumes has been described as mild form of metal fume fever in recent studies. Since chronic systemic inflammation leads to a higher cardiovascular risk, examining the inflammation with the underlying pathomechanism is necessary to estimate and hopefully prevent long-term effects of welding. We established a whole blood assay to investigate the effects of zinc- and copper-containing welding fume particles on the blood immune response. Increased levels of IL-6, IL-8, TNFα and IL-1β determined after 24 hours of exposure indicated an acute systemic inflammatory reaction. In vitro increases of IL-6 were comparable to in vivo increases of serum IL-6 levels in a study with welding fume exposure of human subjects. Inhibition of PTP1B was identified as one pathway responsible for the effects of zinc- and copper-containing welding fumes and therefore welding fume fever. In conclusion, the whole blood assay is a reliable and feasible method to investigate effects of zinc- and copper-containing welding fumes on the immune system and as a surrogate for systemic inflammation and welding fume fever. Future research can utilize whole blood assays to reduce and partially replace human exposure studies for further investigations of welding fume fever.

Necrotic, apoptotic and autophagic cell fates triggered by nanoparticles

Nanomaterials have gained a rapid increase in use in a variety of applications that pertain to many aspects of human life. The majority of these innovations are centered on medical applications and a range of industrial and environmental uses ranging from electronics to environmental remediation. Despite the advantages of NPs, the knowledge of their toxicological behavior and their interactions with the cellular machinery that determines cell fate is extremely limited. This review is an attempt to summarize and increase our understanding of the mechanistic basis of nanomaterial interactions with the cellular machinery that governs cell fate and activity. We review the mechanisms of NP-induced necrosis, apoptosis and autophagy and potential implications of these pathways in nanomaterial-induced outcomes. Abbreviations: Ag, silver; CdTe, cadmium telluride; CNTs, carbon nanotubes; EC, endothelial cell; GFP, green fluorescent protein; GO, graphene oxide; GSH, glutathione; HUVECs, human umbilical vein endothelial cells; NP, nanoparticle; PEI, polyethylenimine; PVP, polyvinylpyrrolidone; QD, quantum dot; ROS, reactive oxygen species; SiO2, silicon dioxide; SPIONs, superparamagnetic iron oxide nanoparticles; SWCNT, single-walled carbon nanotubes; TiO2, titanium dioxide; USPION, ultra-small super paramagnetic iron oxide; ZnO, zinc oxide.

Effect of size and silica coating on structural, magnetic as well as cytotoxicity properties of copper ferrite nanoparticles

Copper ferrite nanoparticles, synthesized by conventional sol-gel method were calcined at different temperatures. The magnetic, structural, morphological and cytotoxicity analyses of the uncalcined and calcined nanoparticles (NPs) were investigated and compared. Formation of tetragonal structure of CuFe₂O₄ NPs was observed in XRD patterns. On increasing the temperature, better crystallinity and increased crystallite size were also observed. In the FTIR spectra, bonds corresponding to CH, OH and carboxylate groups gradually disappeared with increasing temperature, while peak corresponding to FeO existed more prominently. NPs calcined at 300 °C (Cu3) exhibited the highest magnetic saturation and lowest retentivity, thereby indicating its superparamagnetic behaviour. Concentration-dependent cytotoxicity values were obtained by invitro MTT (3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide, a tetrazole) assay, Cell Titer assay and Cell Flow Cytometry with Propidium Iodide. NPs calcined at 300 °C, 500 °C and 700 °C exhibited non-toxicity at all the concentrations. Based on magnetic and biocompatibility analyses, Cu3 NPs were found to be the most suitable one to investigate the influence of silica coating on its surface. Presence of silica was confirmed by XRD pattern, FTIR spectrum, SEM and HRTEM micrographs as well as SAED pattern. In M-H curve, superparamagnetic behaviour of the CuFe₂O₄ core was retained but with reduced magnetic saturation due to magnetically dead layer of silica. An increase in cellular viability was witnessed in case of silica coated CuFe₂O₄ NPs as compared to uncoated NPs, thus reflecting on its enhanced biocompatibility. Nanosized, superparamagnetic and highly biocompatible characteristics make silica coated CuFe₂O₄ NPs a potential claimant for biomedical applications.

Different cytotoxic and apoptotic responses of MCF-7 and HT1080 cells to MnO2 nanoparticles are based on similar mode of action

Manganese (IV) oxide nanoparticles (MnO₂ NPs) are increasingly used in numerous applications. Multiple applications of MnO₂ NPs, however, increase the human exposure and thus potential risk related to their toxicity. There is little information regarding the toxicity mechanisms of MnO₂ NPs in human cells. In this study, we explored the toxic potential of MnO₂ NPs in human breast cancer epithelial (MCF-7) and human fibrosarcoma epithelial (HT1080) cells in order to examine whether epithelial cells of different origins showed similar responses. Results demonstrated that MnO₂ NPs induced cell viability reduction and membrane damage in both MCF-7 and HT1080 cells in a dose-dependent manner. MnO₂ NPs were also found to induce pro-oxidants generation and antioxidants depletion in both cells. We further observed that MnO₂ NPs induce apoptosis in both MCF-7 and HT1080 cells evident by altered regulation of apoptotic genes (p53, bax & bcl-2), cell cycle arrest and low mitochondrial membrane potential. Interestingly, we noticed that HT1080 cells were more susceptible to MnO₂ NPs exposure than those of MCF-7 cells. This could be due to higher level of MnO₂ NPs uptake into HT1080 cells as compared to MCF-7 cells. However, the mechanism of toxicity induced by MnO₂ NPs in both MCF-7 and HT1080 cells was highly similar. This study warrants further research to delineate the underlying mechanisms of MnO₂ NPs toxicity at in vivo level.

Evaluation of the cytotoxic and genotoxic effects of mycotoxin fusaric acid

Fusaric acid (FA) is produced by several Fusarium species and is commonly found in grains. This investigation was performed to evaluate the cytotoxic and genotoxic effects of FA either in human cervix carcinoma (HeLa) cell line using 3-(4,5-dimethylthiazolyl-2)-2,5 diphenyltetrazolium bromide (MTT) assay and in human lymphocytes using chromosome aberrations (CAs), sister chromatid exchanges (SCEs), micronuclei (MN) as well as comet assay in vitro. The cells were treated with 0.78, 1.56, 3.125, 6.25, 12.50, 25, 50, 100, 200, and 400 µg/mL concentrations of FA. It has potent cytotoxic effect on HeLa cell line measured by MTT assay especially at higher concentrations (200, 400 µg/mL). The half of inhibitory concentration (IC₅₀) evidenced by FA in the HeLa cells was 200 μg/mL at 24 h and between 200 and 400 μg/mL at 48 h. It was also observed that FA produced a significant decrease in mitotic index (MI) at 12.50 µg/mL compared to solvent control. Furthermore, it indicated a cytotoxic effect at the concentrations ranging from 25 to 400 μg/mL in human lymphocytes. The results of this research point out that being exposed to FA at high concentrations show cytotoxicity. Besides FA induced comet tail intensity at 3.125, 6.25, and 12.50 µg/mL concentrations in isolated human lymphocytes. On the other hand, no genotoxic effects were seen in human lymphocytes in vitro using CA, SCE and MN assays.

The effects of zinc- and copper-containing welding fumes on murine, rat and human precision-cut lung slices

Recently, the pro-inflammatory effects of metal inert gas brazing welding fumes containing zinc and copper have been demonstrated in humans. Here, murine, rat and human precision cut lung slices (PCLS) were incubated in welding fume containing media with 0.1, 1, 10 and 100 μg/ml for 24 or 48 h. 24 h incubation were determined either by incubation for the total time or for only 6 h followed by a 18 h post-incubation phase. Cytotoxicity, proliferation and DNA repair rates, and cytokine levels were determined. Welding fume particle concentrations of 0.1 and 1 μg/ml showed no toxic effects on PCLS of all three species, while for 10 and 100 μg/ml a concentration-dependent toxicity occurred. Proliferation and DNA repair rates were reduced for all tested concentrations and incubation times. Additionally, the cytokine levels in the supernatants were markedly reduced, while after 6 h of exposure with 18 h of post-incubation time a trend towards increased cytokine levels occurred. PCLS are a reliable and feasible method to assess and offer a prediction of toxic effects of welding fume particles on human lungs. Rat PCLS showed similar responses compared to human PCLS and are suitable for further evaluation of toxic effects exerted by welding fume particles.

Oxidative stress mediated cytotoxicity of tin (IV) oxide (SnO2) nanoparticles in human breast cancer (MCF-7) cells

Due to unique optical and electronic properties tin oxide nanoparticles (SnO₂ NPs) have shown potential for various applications including solar cell, catalyst, and biomedicine. However, there is limited information concerning the interaction of SnO₂ NPs with human cells. In this study, we explored the potential mechanisms of cytotoxicity of SnO₂ NPs in human breast cancer (MCF-7) cells. Results demonstrated that SnO₂ NPs induce cell viability reduction, lactate dehydrogenase leakage, rounded cell morphology, cell cycle arrest and low mitochondrial membrane potential in dose- and time-dependent manner. SnO₂ NPs were also found to provoke oxidative stress evident by generation of reactive oxygen species (ROS), hydrogen peroxide (H₂O₂) and lipid peroxidation, while depletion of glutathione (GSH) level and lower activity of several antioxidant enzymes. Remarkably, we observed that ROS generation, GSH depletion, and cytotoxicity induced by SnO₂ NPs were effectively abrogated by antioxidant N-acetylcycteine. Our data have shown that SnO₂ NPs induce toxicity in MCF-7 cells via oxidative stress. This study warrants further research to explore the genotoxicity of SnO₂ NPs in different types of cancer cells.

Ag-doping regulates the cytotoxicity of TiO2 nanoparticles via oxidative stress in human cancer cells

We investigated the anticancer potential of Ag-doped (0.5-5%) anatase TiO2 NPs. Characterization study showed that dopant Ag was well-distributed on the surface of host TiO2 NPs. Size (15 nm to 9 nm) and band gap energy (3.32 eV to 3.15 eV) of TiO2 NPs were decreases with increasing the concentration of Ag dopant. Biological studies demonstrated that Ag-doped TiO2 NP-induced cytotoxicity and apoptosis in human liver cancer (HepG2) cells. The toxic intensity of TiO2 NPs was increases with increasing the amount of Ag-doping. The Ag-doped TiO2 NPs further found to provoke reactive oxygen species (ROS) generation and antioxidants depletion. Toxicity induced by Ag-doped TiO2 NPs in HepG2 cells was efficiently abrogated by antioxidant N-acetyl-cysteine (ROS scavenger). We also found that Ag-doped TiO2 NPs induced cytotoxicity and oxidative stress in human lung (A549) and breast (MCF-7) cancer cells. Interestingly, Ag-doped TiO2 NPs did not cause much toxicity to normal cells such as primary rat hepatocytes and human lung fibroblasts. Overall, we found that Ag-doped TiO2 NPs have potential to selectively kill cancer cells while sparing normal cells. This study warranted further research on anticancer potential of Ag-doped TiO2 NPs in various types of cancer cells and in vivo models.

Copper doping enhanced the oxidative stress-mediated cytotoxicity of TiO2 nanoparticles in A549 cells

Physicochemical properties of titanium dioxide nanoparticles (TiO₂ NPs) can be tuned by doping with metals or nonmetals. Copper (Cu) doping improved the photocatalytic behavior of TiO₂ NPs that can be applied in various fields such as environmental remediation and nanomedicine. However, interaction of Cu-doped TiO₂ NPs with human cells is scarce. This study was designed to explore the role of Cu doping in cytotoxic response of TiO₂ NPs in human lung epithelial (A549) cells. Characterization data demonstrated the presence of both TiO₂ and Cu in Cu-doped TiO₂ NPs with high-quality lattice fringes without any distortion. The size of Cu-doped TiO₂ NPs (24 nm) was lower than pure TiO₂ NPs (30 nm). Biological results showed that both pure and Cu-doped TiO₂ NPs induced cytotoxicity and oxidative stress in a dose-dependent manner. Low mitochondrial membrane potential and higher caspase-3 enzyme (apoptotic markers) activity were also observed in A549 cells exposed to pure and Cu-doped TiO₂ NPs. We further observed that cytotoxicity caused by Cu-doped TiO₂ NPs was higher than pure TiO₂ NPs. Moreover, antioxidant N-acetyl cysteine effectively prevented the reactive oxygen species generation, glutathione depletion, and cell viability reduction caused by Cu-doped TiO₂ NPs. This is the first report showing that Cu-doped TiO₂ NPs induced cytotoxicity and oxidative stress in A549 cells. This study warranted further research to explore the role of Cu doping in toxicity mechanisms of TiO₂ NPs.

Silica nanoparticles induced intrinsic apoptosis in neuroblastoma SH-SY5Y cells via CytC/Apaf-1 pathway

The present study was to investigate effects of Silica nanoparticles (SiNPs) on nervous system and explore potential mechanisms in human neuroblastoma cells (SH-SY5Y). Cytotoxicity was detected by cell viability and Lactate dehydrogenase (LDH) release. Flow cytometry analysis was applied to assess mitochondrial membrane potential (MMP) loss, intracellular Ca²⁺ and apoptosis. To clarify the mechanism of SiNPs-induced apoptosis, intrinsic apoptosis-related proteins were detected. Our results showed that SiNPs caused cytotoxicity, cell membrane damage and Ca²⁺ increase in a dose-dependent manner in SH-SY5Y cells. Both the mitochondrial membrane potential (MMP) loss and potential mitochondria damage resulted in Cyt C release to the cytoplasm. The elevated Cyt C and Apaf1 further triggered intrinsic apoptosis via executive molecular caspase-9 and caspase-3. The present study confirmed that SiNPs induced intrinsic apoptosis in neuroblastoma SH-SY5Y cells via CytC/Apaf-1 pathway and provided a better understanding of the potential toxicity induced by SiNPs on human neurocyte.

Phytotoxic effects of seaweed mediated copper nanoparticles against the harmful alga: Lyngbya majuscula

In this study, copper nanoparticles (Cu-NPs) were synthesized using Corallina officinalis Linnaeus and Corallina mediterranea Areschoug aqueous extracts. Transmission Electron microscope indicated that the biosynthesized Cu-NPs averaged 12.7 nm and 13.6 nm for C. Officinalis and C. mediterranea, respectively. As reported by the FT-IR analyses, the algal extracts contain phyto-chemicals such as proteins, carboxylic acids, complex carbohydrates; these compounds will act as encapsulating agents and be reduced from copper sulphate to Cu-NPs. Energy-dispersive analyses X-ray (EDX) confirmed the copper composition in the synthesized Cu-NPs. The biosynthesized Cu-NPs arrested the growth of Lyngbya majuscula and presented in time and concentration dependent trends. At a concentration of 2 μg/mL, Cu-NPs, synthesized by C. officinalis exerted 85 ± 4% reduction of the algae dry weight. Increasing Cu-NPs concentration led to excellent reduction, which is a very promising result. Cupper-NPs synthesized by C. mediterranea produced moderate effects on L. majuscula. The results also indicated that there were sharp decreases in chlorophyll a content in L. majuscula with the increase in Cu-NPs concentrations. Using 4 μg/mL of Cu-NPs derived from C. officinalis, chlorophyll a decreased by 48 ± 5%. On the other hand, lower reductions in chlorophyll a were recorded upon using Cu-NPs synthesized using C. mediterranea (36 ± 3% and 41 ± 5% reductions at concentrations of 2 μg/mL and 4 μg/mL, respectively). The results of this study suggested that the bioactive and allelopathic compounds derived from the two algal extracts coating the (Cu2+) together with (Cu2+) are responsible for the inhibitive impacts of Cu-NPs on L. majuscula.

Pitfalls and Challenges in Nanotoxicology: A Case of Cobalt Ferrite (CoFe2O4) Nanocomposites

Nanotechnology is developing at a rapid pace with promises of a brilliant socio-economic future. The apprehensions of vivid future involvement with nanotechnology make nanoobjects ubiquitous in the macroscopic world of humans. Nanotechnology helps us to visualize the new mysterious horizons in engineering, sophisticated electronics, environmental remediation, biosensing, and nanomedicine. In all these hotspots, cobalt ferrite (CoFe) nanoparticles (NPs) are outstanding contestants because of their astonishing controllable physicochemical and magnetic properties with ease of synthesis methods. The extensive use of CoFe NPs may result in CoFe NPs easily penetrating the human body unintentionally by ingestion, inhalation, adsorption, etc. and intentionally being instilled into the human body during biomedical diagnostics and treatment. After being housed in the human body, it might induce oxidative stress, cytotoxicity, genotoxicity, inflammation, apoptosis, and developmental, metabolic and hormonal abnormalities. In this review, we compiled the toxicity knowledge of CoFe NPs aimed to provide the safe usage of this breed of nanomaterials.

Can CuO nanoparticles lead to epigenetic regulation of antioxidant enzyme system?

Copper has been used from ancient time in various applications. Scientists have exploited its means of exposure and consequences to living organisms. The peculiar property of nanomaterials that is a high surface to volume ratio has increased the range of application in products. Copper oxide nanoparticles (CuO NPs) are widely used in industrial applications such as semiconductor devices, gas sensor, batteries, solar energy converter, microelectronics, heat transfer fluids and consumer products. In contrast, acute toxicity of CuO NPs has also been reported. Subsequently, human and environmental health may be at a high risk. Their frequent use can also contaminate ecosystems. Therefore, the toxicity of CuO NPs needs to be thoroughly understood. In this review, we have tried to discuss the recent facts and mechanism that have been explored for CuO NPs-induced toxicity at a cellular, in vivo and ecotoxicological level. Accordingly, the main cause for induction of toxicity by CuO NPs is the generation of reactive oxygen species (ROS) followed by the mitochondrial destruction that leads to apoptosis via the intrinsic pathway or under the condition such as hypoxia cell on exposure to CuO NPs may commit to necrosis. Moreover, CuO NPs also result in activation of MAPK pathways, ERKs and JNK/SAPK thus play an important role in the activation of AP-1. Furthermore, CuO NPs also leads to up-regulation of p53 and caspase three genes. Therefore, careful measures are required to explore omic technology to understand the molecular mechanism of the deleterious effects caused by CuO NPs. Copyright © 2016 John Wiley & Sons, Ltd.

In vitro and in vivo evaluation of the toxicities induced by metallic nickel nano and fine particles

Nickel nanoparticles (Ni NPs) have been applied in various fields along with the rapid development of nanotechnology. However, the potential adverse health effects of the Ni NPs are unclear. To investigate the cyto- and genotoxicity and compare the differences between the Ni NPs and the nickel fine particles (Ni FPs), Sprague-Dawley (SD) rats and A549 cells were treated with different doses of Ni NPs or FPs. Intra-tracheal instillation of Ni NPs and FPs caused acute toxicity in the lungs, liver and kidneys of the SD rats. Even though the histology of the lungs showed hyperplastic changes and the protein expression of HO-1 and Nrf2 detected by western blot showed lung burden overload, no significant increase was observed to the expression level of oncoprotein C-myc. The results from cell titer-Glo assay and comet assay indicated that Ni NPs were more potent in causing cell toxicity and genotoxicity in vitro than Ni FPs. In addition, Ni NPs increased the expression of C-myc in vitro, but these increases may not have been due to oxidative stress since no significant dose-dependent changes were seen in HO-1 and Nrf2 expressions. Although Ni NPs have the potential to cause DNA damage in A549 cells in vitro, the molecular mechanisms that led to these changes and their tumorigenic potential is still debatable. In short, Ni NPs were more potent in causing cell toxicity and genotoxicity in vitro than Ni FPs, and intra-tracheal instillation of Ni NPs and FPs caused toxicity in organs of the SD rats, while it showed similar to the effects for both particle types. These results suggested that both Ni NPs and FPs have the potential to be harmful to human health, and Ni NPs may have higher cyto- and genotoxic effects than Ni FPs under the same treatment dose.

In vitro and in vivo evaluation of the toxicities induced by metallic nickel nano and fine particles

Nickel nanoparticles (Ni NPs) have been applied in various fields along with the rapid development of nanotechnology. However, the potential adverse health effects of the Ni NPs are unclear. To investigate the cyto- and genotoxicity and compare the differences between the Ni NPs and the nickel fine particles (Ni FPs), Sprague-Dawley (SD) rats and A549 cells were treated with different doses of Ni NPs or FPs. Intra-tracheal instillation of Ni NPs and FPs caused acute toxicity in the lungs, liver and kidneys of the SD rats. Even though the histology of the lungs showed hyperplastic changes and the protein expression of HO-1 and Nrf2 detected by western blot showed lung burden overload, no significant increase was observed to the expression level of oncoprotein C-myc. The results from cell titer-Glo assay and comet assay indicated that Ni NPs were more potent in causing cell toxicity and genotoxicity in vitro than Ni FPs. In addition, Ni NPs increased the expression of C-myc in vitro, but these increases may not have been due to oxidative stress since no significant dose-dependent changes were seen in HO-1 and Nrf2 expressions. Although Ni NPs have the potential to cause DNA damage in A549 cells in vitro, the molecular mechanisms that led to these changes and their tumorigenic potential is still debatable. In short, Ni NPs were more potent in causing cell toxicity and genotoxicity in vitro than Ni FPs, and intra-tracheal instillation of Ni NPs and FPs caused toxicity in organs of the SD rats, while it showed similar to the effects for both particle types. These results suggested that both Ni NPs and FPs have the potential to be harmful to human health, and Ni NPs may have higher cyto- and genotoxic effects than Ni FPs under the same treatment dose.