Nanotoxicology最新文献

Understanding the biokinetics of nanoparticles will support the identification of target organs for toxicological endpoints. We investigated the biokinetics of poorly soluble nanomaterials carbon black, multi-walled carbon nanotubes (MWCNT), cerium oxide (CeO₂), titanium dioxide (TiO₂), crystalline silica (SiO₂) in inhalation studies in rodents (the soluble amorphous silica was also included). By reviewing research papers on the inhalation of these substances, we collected physico-chemical data and elemental distribution to organs, urine, and feces. Carbon black, MWCNT, cerium, and titanium accumulated during exposure and persisted in the lung post-exposure (still present at >3000 h). For silica, the amorphous form resulted in silicon accumulation in the lungs. Silicon was increased in the blood. Lymph node accumulation was observed for MWCNT, cerium, and titanium. Liver accumulation was observed for cerium and titanium. Cerium and silicon were increased in the spleen. Titanium accumulated and remained in the spleen (>4000 h). MWCNT were increased in several organs, some of which had a persistent presence of this material. In conclusion, we collected data on the biodistribution of five nanomaterials that, except for amorphous silica, are poorly soluble. The poorly soluble materials or their elements were persistent in the lungs but also showed persistence in other organs. In addition, the data on lung content supports Haber's rule, with titanium being deposited to a greater extent at exposure end than the other materials. Lung deposition seems relatively linear for the collected MMAD values, indicating size may be less important than previously suggested regarding alveolar deposition of the sub-2-micrometer size.

Successful implementation of Safe and Sustainable by Design (SSbD) and grouping approaches requires simple, reliable, and cost-effective assays to facilitate hazard screening at early stages of product development. Especially for nanomaterials (NMs), which exist in many different forms, efficient hazard screening is of utmost importance. Oxidative potential (OP), which is the ability of a substance to induce reactive oxygen species (ROS), is an important indicator of the potential to induce oxidative damage and oxidative stress. A frequently used assay to measure OP of NMs is the ferric reducing ability of serum (FRAS) assay. Although the widely used cuvette-based FRAS protocol is considered a robust assay, its low throughput makes the screening of multiple materials challenging. Here, we adapt the original cuvette-based FRAS assay protocol, into a 96-well format and thereby improve its user-friendliness, simplicity, and screening capacity. The adapted protocol allows for the screening of multiple NMs per plate, and multiple plates per day, where the original protocol allows for the screening of one NM dose-range per day. When comparing the two protocols, the adapted protocol showed slightly decreased assay precision as compared to the original protocol. The results obtained with the adapted protocol were compared using eight reference NMs in an interlaboratory study and showed acceptably low intra- and interlaboratory variation. We conclude that the adapted FRAS assay protocol is suitable to be used for hazard screening to facilitate SSbD and grouping approaches.

Carbon nanomaterials have been widely applied for cutting edge therapeutic applications as they offer tunable physio-chemical properties with economic scale-up options. Nuclear delivery of cancer drugs has been of prime focus since it controls important cellular signaling functions leading to greater anti-cancer drug efficacies. Better cellular drug uptake per unit drug injection drastically reduces severe side-effects of cancer therapies. Similarly, carbon dots (CDs) uptaken by the nucleus can also be used to set-up cutting edge nano delivery systems. In an earlier paper, we showed the cellular uptake and plasma membrane impact of combustion generated yellow luminescing CDs produced by our group from fuel rich combustion reactors in a one-step tunable production. In this paper, we aim to specifically study the nucleus by establishing the uptake kinetics of these combustion-generated yellow luminescing CDs. At sub-lethal doses, after crossing the plasma membrane, they impact the actin and microtubule mesh, affecting cell adhesion and migration; enter nucleus by diffusion processes; modify the overall appearance of the nucleus in terms of morphology; and alter chromatin condensation. We thus establish how this one-step produced, cost and bulk production friendly carbon dots from fuel rich combustion flames can be innovatively repurposed as potential nano delivery agents in cancer cells.

Zinc oxide (ZnO) and nickel oxide (NiO) nanoparticles (NPs) are widely used in various industries due to their distinctive physico-chemical and biological properties. However, concerns have been raised about their potential toxicity in humans. While many studies have reviewed their effects on visceral organs upon ingestion, inhalation, or skin contact, limited reviews are available regarding their adverse consequences on the liver and kidneys resulting from intraperitoneal administration in rats. Hence, this systematic review is the first to uniquely address this issue. A systematic search was performed on PubMed and Google scholar to identify articles that explored the toxic effects of ZnO-NPs and NiO-NPs in rats following intraperitoneal injection. The quality of the articles was assessed using SYCLE's risk of bias tool, leading to the selection of 16 articles; 14 for ZnO-NPs, 1 for NiO-NPs and 1 for both NPs. This review revealed that ZnO-NPs induces an acute toxicity in liver and kidney that is dose dependent. The impairments were marked by changes in organs functional markers, lipid and glucose levels and antioxidant deficiencies and lipid peroxidation. NiO-NPs also showed considerable toxicity, despite the limited studies. Further, variability of physico-chemical properties among studies complicated the toxicity assessment. To conclude, this study provides a novel contribution by summarizing the literature findings that suggest potential adverse intraperitoneal hepatorenal toxic outcomes associated with ZnO-NPs and NiO-NPs. Future research should focus on long-term effects and standardizing protocols to ensure the safe use of ZnO-NPs and NiO-NPs in industrial and clinical practices.

Immunostimulation caused by nanoparticles may be beneficial or adverse depending on their intended application. Activation of immune cells is beneficial for indications targeting the immune system for therapeutic purposes, such as tumor microenvironment reprogramming, immunotherapy, and vaccines. When it is unwanted, however, immunostimulation may lead to excessive inflammation, cytokine storm, and hypersensitivity reactions. The increasing use of silica nanoparticles (SiNPs) for the delivery of drugs, imaging agents, and antigens warrants preclinical studies aimed at understanding carrier-mediated effects on the number, activation status, and function of immune cell subsets. Herein, we present an in vitro study utilizing primary human peripheral blood mononuclear cells (PBMC) to investigate the proinflammatory properties of four types of SiNPs varying in size and porosity. Cytokine analysis was performed in resting and LPS-primed PBMC cultures to understand the ability of silica nanoparticles to induce de novo and exaggerate preexisting inflammation, respectively. Changes in the number and activation status of lymphoid and myeloid cells were studied by flow cytometry to gain further insight into SiNP-mediated immunostimulation. Nonporous SiNPs were found to be more proinflammatory than mesoporous SiNPs, and larger-sized particles induced greater cytokine response. LPS-primed PBMC resulted in increased susceptibility to SiNPs. Immunophenotyping analysis of SiNP-treated PBMC resulted in T and B lymphocyte, natural killer cell, and dendritic cell activation. Additionally, a loss of regulatory T cells and an increase in γδ TCR T cell population were observed with all particles. These findings have implications for the utility of SiNPs for the delivery of drugs and imaging agents.

Silica nanoparticles are increasingly considered for drug delivery applications. These applications require an understanding of their biocompatibility, including their interactions with the immune system. However, systematic studies for silica nanoparticle immunological safety profiles are lacking. To fill this gap, we conducted an in vitro study investigating various aspects of silica nanoparticles' interactions with blood and immune cells. Four types of silica nanoparticles with variations in size and porosity were studied. These included nonporous Stöber silica nanoparticles with average diameters of approximately 50 and 100 nm (SNP50 and SNP100), mesoporous silica nanoparticles of approximately 100 nm (Meso100), and hollow mesoporous silica nanoparticles of approximately 100 nm (HMSNP100) in diameter, respectively. The hematological compatibility was assessed using hemolysis, complement activation, platelet aggregation, and plasma coagulation assays. The effects of nanoparticles on immune cell function were studied using in vitro phagocytosis, chemotaxis, natural killer cell cytotoxicity, leukocyte proliferation, human lymphocyte activation, colony-forming unit granulocyte-macrophage, and leukocyte procoagulant activity assays. The in vitro findings suggest that at high concentrations, corresponding to the in vivo human dose of 40 mg/kg, silica nanoparticles demonstrated an array of immunotoxic effects that depended on their physicochemical properties. However, all types of silica nanoparticles studied were not immunotoxic at concentrations corresponding to lower doses (≤ 8 mg/kg) comparable to that of nanocarriers in other nanomedicines currently used in the clinic. These findings are promising for using silica nanoparticles for the systemic delivery of bioactive and imaging agents.

A critical review of the current state-of-the-science for the physiologically based pharmacokinetic (PBPK) modeling of metal nanoparticles and their application to human health risk assessment for inhalation exposures was conducted. A systematic literature search was used to identify four model groups (defined as a primary publication along with multiple supplementary publications) subject to review. Using a recent guideline document from the Organization for Economic Cooperation and Development (OECD) for PBPK model evaluation, these model groups were critically peer-reviewed by an independent panel of experts to identify those to be considered for modeling and simulation application. Based upon the expert panel input, model confidence scores for the four model groups ranged from 30 to 41 (out of a maximum score of 50). The three highest-scoring model groups were then applied to compare predictions to a different metal nanoparticle (i.e. not specifically used to parameterize the original models) using a recently published data set for tissue burdens in rats, as well as predicting human tissue burdens expected for corresponding occupational exposures. Overall, the rat models performed reasonably well in predicting the lung but tended to overestimate systemic tissue burdens. Data needs for improving the state-of-the-science, including quantitative particle characterization in tissues, nanoparticle-corona data, long-term exposure data, interspecies extrapolation methods, and human biomonitoring/toxicokinetic data are discussed.

Nano-sized titanium dioxide particles (TiO₂ NPs) are a high-production volume nanomaterial widely used in the paints, cosmetics, food and photovoltaics industry. However, the potential carcinogenic effects of TiO₂ NPs in the lung are still unclear despite the vast number of in vitro and in vivo studies investigating TiO₂ NPs. Here, we systematically reviewed the existing in vitro and in vivo mechanistic evidence of TiO₂ NP lung carcinogenicity using the ten key characteristics of carcinogens for identifying and classifying carcinogens. A total of 346 studies qualified for the quality and reliability assessment, of which 206 were considered good quality. Using a weight-of-evidence approach, these studies provided mainly moderate to high confidence for the biological endpoints regarding genotoxicity, oxidative stress and chronic inflammation. A limited number of studies investigated other endpoints important to carcinogenesis, relating to proliferation and transformation, epigenetic alterations and receptor-mediated effects. In summary, TiO₂ NPs might possess the ability to induce chronic inflammation and oxidative stress, but it was challenging to compare the findings in the studies due to the wide variety of TiO₂ NPs differing in their physicochemical characteristics, formulation, exposure scenarios/test systems, and experimental protocols. Given the limited number of high-quality and high-reliability studies identified within this review, there is a lack of good enough mechanistic evidence for TiO₂ NP lung carcinogenicity. Future toxicology/carcinogenicity research must consider including positive controls, endotoxin testing (where necessary), statistical power analysis, and relevant biological endpoints, to improve the study quality and provide reliable data for evaluating TiO₂ NP-induced lung carcinogenicity.