Toxicity of Fe2 O3 nanoparticles on human blood lymphocytes

Toxicity mechanism of engineered nanomaterials: Focus on mitochondria

With the rapid development of nanotechnology, engineered nanomaterials (ENMs) are widely used in various fields. This has exacerbated the environmental pollution and human exposure of ENMs. The study of toxicity of ENMs and its mechanism has become a hot research topic in recent years. Mitochondrial damage plays an important role in the toxicity of ENMs. This paper reviews the structural damage, dysfunction, and molecular level perturbations caused by different ENMs to mitochondria, including ZnO NPs, Ag NPs, TiO2 NPs, iron oxide NPs, cadmium-based quantum dots, CuO NPs, silica NPs, carbon-based nanomaterials. Among them, mitochondrial quality control plays an important role in mitochondrial damage. We further summarize the cellular level outcomes caused by mitochondrial damage, mainly including, apoptosis, ferroptosis, pyroptosis and inflammation response. In addition, we concluded that reducing mitochondrial damage at source as well as accelerating recovery from mitochondrial damage through ENMs modification and pharmacological intervention are two feasible strategies. This review further provides new insights into the mitochondrial toxicity mechanisms of ENMs and provides a new foothold for predicting human health and environmental risks of ENMs.

Modification of insulating oils and oil-based titanium dioxide nanofluids for transformers: a review

In the last decade, oil-based titanium dioxide nanofluids (TiO2 NFs) have gained immense interest due to their unique insulating properties and excellent thermal performance, which endow them with the potential for application in the field of modified insulating oils. A timely comparison, analysis and summary of recent advances in the preparation, characterization, and properties of different oil-based TiO2 NFs for oil-immersed power transformers will contribute to provide a useful reference for the subsequent development of such materials. Preparation methods are reviewed along with their merits and demerits. Characterization techniques including scanning electron microscopy (SEM), transmission electron microscopy (TEM), optical microscopy (OM), X-ray diffraction (XRD), energy-dispersive X-ray spectroscopy (EDX), dynamic light scattering (DLS), Fourier transform infrared (FTIR) spectroscopy, thermally stimulated current (TSC), pulse electroacoustic technique (PEA), finite element analysis (FEA), fluorescence spectroscopy, Raman spectroscopy and zeta potential analysis are all applied to determine the crystal structure, particle size, surface function, surface charge and stability. Stabilization mechanisms are also discussed in detail. Some critical properties of oil-based TiO2 NFs under the application of different influencing factors such as base oils, crystal structure, size of nanoparticles, surface modifiers, mixing percentage, and aging environment are highlighted. Finally, the existing challenges and perspectives are presented for future research.

Recent Advances in the Gastrointestinal Fate of Organic and Inorganic Nanoparticles in Foods

Inorganic or organic nanoparticles are often incorporated into foods to enhance their quality, stability, nutrition, or safety. When they pass through the gastrointestinal environment, the properties of these nanoparticles are altered, which impacts their biological effects and potential toxicity. Consequently, there is a need to understand how different kinds of nanoparticles behave within the gastrointestinal tract. In this article, the current understanding of the gastrointestinal fate of nanoparticles in foods is reviewed. Initially, the fundamental physicochemical and structural properties of nanoparticles are discussed, including their compositions, sizes, shapes, and surface chemistries. Then, the impact of food matrix effects and gastrointestinal environments on the fate of ingested nanoparticles is discussed. In particular, the influence of nanoparticle properties on food digestion and nutraceutical bioavailability is highlighted. Finally, future research directions are highlighted that will enable the successful utilization of nanotechnology in foods while also ensuring they are safe.

Toxicity of Hydrogen Sulfide on Rat Brain Neurons

Hydrogen sulfide (H₂S) is a toxic compound known as a member of the gasotransmitter family. H₂S has the ability to inhibit the cytochrome c oxidase enzyme in the mitochondrial respiratory chain. Mitochondria play an important role in energy production and the brain needs energy for normal function. Mitochondrial dysfunction is associated with neurodegenerative diseases. This study investigated the mechanisms of cytotoxicity induced by H₂S in brain neurons. thioacetamide has been used to produce H₂S in water solutions. The results of the study showed that thioacetamide at concentrations of 116, 232 and 464 µg/ml was able to increase the level of reactive oxygen species (ROS), collapse in mitochondrial membrane potential (MMP), damage to the lysosomal membrane, increase in the level of oxidized glutathione (GSSG) and decrease in the level of reduced glutathione (GSH) in brain neurons. The results of the study suggested that H₂S causes damage to mitochondria and lysosomes in brain neurons that could be associated with neurodegenerative diseases.

Protective Effect of Lactobacillus rhamnosus GG on TiO2 Nanoparticles-Induced Oxidative Stress Damage in the Liver of Young Rats

The potential toxicity of titanium dioxide nanoparticles (TiO₂ NPs) to mammals has become a widespread concern. Young individuals exposed to TiO₂ NPs have a higher risk than adults. In this study, the protective effects of Lactobacillus rhamnosus GG (LGG) on liver toxicity in young rats induced by TiO₂ NPs were explored. Results show that the four-week-old rats that underwent LGG after the oral intake of TiO₂ NPs could prevent weight loss, reduce hematological indicators (WBC and NEUT) and serum biochemical indicators (AST, ALT, AST/ALT, and ALP). Moreover, it alleviated the pathological damage of the liver (as indicated by the disordered hepatocytes, more eosinophilic, ballooning degeneration, and accompany with blood cells), but it did not reduce the Ti contents in the liver. In addition, RT-qPCR results indicated that LGG restored the expression of anti-oxidative stress-related genes, such as SOD1, SOD2, CAT, HO-1, GSH, GCLC, and GCLM in the liver. In summary, the hepatotoxicity of TiO₂ NPs in young rats is closely related to oxidative stress, and the antioxidant effect of LGG might protect the harmful effects caused by TiO₂ NPs.

Selective anticancer activity of superparamagnetic iron oxide nanoparticles (SPIONs) against oral tongue cancer using in vitro methods: The key role of oxidative stress on cancerous mitochondria

Today, it has been proven that the nanoparticles such as superparamagnetic iron oxide nanoparticles (SPIONs) have widespread use in biomedical applications, for instance, in magnetic resonance imaging and targeted delivery of drugs. Despite many studies on SPIONs in diagnosing some diseases like cancer, it has not been investigated on the oral tongue squamous cell carcinoma (OTSCC) detection by the NPs. Hence, the present study has been designed to assess the in vitro cytotoxicity of SPIONs on the isolated mitochondria of OTSCC by mitochondrial tests. Isolated mitochondria were removed from the separated cancer and control tissues from the squamous cells of tango in male Wistar rats (6 or 8 weeks) and exposed to the different concentrations of SPIONs (30, 60, and 120 nM). A rise in the production of reactive oxygen species is one of the significant mechanisms of this study, followed by a collapse of mitochondrial membrane potential, the escape of mitochondrial cytochrome c, and mitochondrial swelling in the exposed isolated mitochondria of OTSCC with SPIONs. Furthermore, our results indicated that the exposure to the SPIONs reduced the activity of succinate dehydrogenase in complex II of the mitochondria obtained from cancerous oral tongue squamous. So the SPIONs can induce selective cytotoxicity on the OTSCC mitochondria without significant effects on the control mitochondria. Based on the results and further studies about in vivo experiments in this regard, it is concluded the SPIONs may be a hopeful therapeutic candidate for the treatment of OTSCC.