Protein Fe-S Centers as a Molecular Target of Toxicity of a Complex Transition Metal Oxide Nanomaterial with Downstream Impacts on Metabolism and Growth

Optical Chemosensors Synthesis and Appplication for Trace Level Metal Ions Detection in Aqueous Media: A Review

In recent years, the development of optical chemosensors for the sensitive and selective detection of trace level metal ions in aqueous media has garnered significant attention within the scientific community. This review article provides a comprehensive overview of the synthesis strategies and applications of optical chemosensors dedicated to the detection of metal ions at low concentrations in water-based environments. The discussion encompasses a wide range of metal ions, including but not limited to heavy metals, transition metals, and rare earth elements, emphasizing their significance in environmental monitoring, industrial processes, and biological systems. The review explores into the synthesis methodologies employed for designing optical chemosensors, discovering diverse materials like organic dyes, nanoparticles, polymers, and hybrid materials. Special attention is given to the design principles that enable the selective recognition of specific metal ions, highlighting the role of ligand chemistry, coordination interactions, and structural modifications. Furthermore, the article thoroughly surveys the analytical performance of optical chemosensors in terms of sensitivity, selectivity, response time, and detection limits. Real-world applications, including water quality assessment, environmental monitoring, and biomedical diagnostics, are extensively covered to underscore the practical relevance of these sensing platforms. Additionally, the review sheds light on emerging trends, challenges, and future prospects in the field, providing insights into potential advancements and innovations. By synthesizing the current state of knowledge on optical chemosensors for trace level metal ions detection. The collective information presented herein not only offers a comprehensive understanding of the existing technologies but also inspires future research endeavors to address the evolving demands in the realm of trace metal ion detection.

α-tocopherol ameliorates copper II oxide nanoparticles-induced cytotoxic, biochemical, apoptotic, and genotoxic damages in the rainbow trout gonad cells-2 (RTG-2) culture

We investigated the effects of α-tocopherol on oxidative stress-caused damage caused by copper II oxide nanoparticles (CuO NPs) on Oncorhynchus mykiss gonadal cells (RTG-2) for 24 and 48 h. α-Tocopherol reversed the cell death and alterations in the expressions of genes such as sod1, gpx1a, gpx4b, and igf2 caused by CuO NPs; it also supported the expressions of cat, igf1, and gapdh genes caused by CuO NPs for 24 h and promoted alterations in the expressions of the sod2, gh1, and igf1 genes for 48 h. Additionally, α-tocopherol reversed the caspase 3/7 activity increased by CuO NPs for 24 h and supported it's decrease for 48 h. α-Tocopherol supported the increase in tail DNA (%) affected by CuO NPs for 24 h and reversed it for 48 h. Therefore, α-tocopherol may have the potential to protect against cellular alterations induced by CuO NPs in a time-dependent manner.

Influences of l-ascorbic acid on cytotoxic, biochemical, and genotoxic damages caused by copper II oxide nanoparticles in the rainbow trout gonad cells-2

In parallel with the raising use of copper oxide nanoparticles (CuO NPs) in various industrial and commercial practices, scientific reports on their release to the environment and toxicity are increasing. The toxicity of CuO NPs is mostly based on their oxidative stress. Therefore, it is necessary to investigate the efficacy of well-known therapeutic agents as antioxidants against CuO NPs damage. This study aimed to investigate the mechanism of this damage and to display whether l-ascorbic acid could preserve against the cell toxicities induced by CuO NPs in the rainbow trout gonad cells-2 (RTG-2). While CuO NPs treatment significantly diminished cell viability, the l-ascorbic acid supplement reversed this. l-ascorbic acid treatment reversed the changes in expressions of sod1, sod2, gpx1a, and gpx4b genes while playing a supportive role in the changes in the expression of the cat gene induced by CuO NPs treatment. Moreover, CuO NPs treatment caused an upregulation in the expressions of growth-related genes (gh1, igf1, and igf2) and l-ascorbic acid treatment further increased these effects. CuO NPs treatment significantly up-regulated the expression of the gapdh gene (glycolytic enzyme gene) compared to the control group, and l-ascorbic acid treatment significantly down-regulated the expression of the gapdh gene compared to CuO NPs treatment. The genotoxicity test demonstrated that l-ascorbic acid treatment increased the genotoxic effect caused by CuO NPs by acting as a co-mutagen. Based on the findings, l-ascorbic acid has the potential to be sometimes inhibitory and sometimes supportive of cellular mechanisms caused by CuO NPs.

Cross-species transcriptomic signatures identify mechanisms related to species sensitivity and common responses to nanomaterials

Physico-chemical characteristics of engineered nanomaterials are known to be important in determining the impact on organisms but effects are equally dependent upon the characteristics of the organism exposed. Species sensitivity may vary by orders of magnitude, which could be due to differences in the type or magnitude of the biochemical response, exposure or uptake of nanomaterials. Synthesizing conclusions across studies and species is difficult as multiple species are not often included in a study, and differences in batches of nanomaterials, the exposure duration and media across experiments confound comparisons. Here three model species, Danio rerio, Daphnia magna and Chironomus riparius, that differ in sensitivity to lithium cobalt oxide nanosheets are found to differ in immune-response, iron-sulfur protein and central nervous system pathways, among others. Nanomaterial uptake and dissolution does not fully explain cross-species differences. This comparison provides insight into how biomolecular responses across species relate to the varying sensitivity to nanomaterials.

Expression Patterns of Energy-Related Genes in Single Cells Uncover Key Isoforms and Enzymes That Gain Priority Under Nanoparticle-Induced Stress

Cellular responses to nanoparticles (NPs) have been largely studied in cell populations, providing averaged values that often misrepresent the true molecular processes that occur in the individual cell. To understand how a cell redistributes limited molecular resources to achieve optimal response and survival requires single-cell analysis. Here we applied multiplex single molecule-based fluorescence in situ hybridization (fliFISH) to quantify the expression of 10 genes simultaneously in individual intact cells, including glycolysis and glucose transporter genes, which are critical for restoring and maintaining energy balance. We focused on individual gill epithelial cell responses to lithium cobalt oxide (LCO) NPs, which are actively pursued as cathode materials in lithium-ion batteries, raising concerns about their impact on the environment and human health. We found large variabilities in the expression levels of all genes between neighboring cells under the same exposure conditions, from only a few transcripts to over 100 copies in individual cells. Gene expression ratios among the 10 genes in each cell uncovered shifts in favor of genes that play key roles in restoring and maintaining energy balance. Among these genes are isoforms that can secure and increase glycolysis rates more efficiently, as well as genes with multiple cellular functions, in addition to glycolysis, including DNA repair, regulation of gene expression, cell cycle progression, and proliferation. Our study uncovered prioritization of gene expression in individual cells for restoring energy balance under LCO NP exposures. Broadly, our study gained insight into single-cell strategies for redistributing limited resources to achieve optimal response and survival under stress.

Energy Starvation in Daphnia magna from Exposure to a Lithium Cobalt Oxide Nanomaterial

Growing evidence across organisms points to altered energy metabolism as an adverse outcome of metal oxide nanomaterial toxicity, with a mechanism of toxicity potentially related to the redox chemistry of processes involved in energy production. Despite this evidence, the significance of this mechanism has gone unrecognized in nanotoxicology due to the field's focus on oxidative stress as a universal─but nonspecific─nanotoxicity mechanism. To further explore metabolic impacts, we determined lithium cobalt oxide's (LCO's) effects on these pathways in the model organism Daphnia magna through global gene-expression analysis using RNA-Seq and untargeted metabolomics by direct-injection mass spectrometry. Our results show that a sublethal 1 mg/L 48 h exposure of D. magna to LCO nanosheets causes significant impacts on metabolic pathways versus untreated controls, while exposure to ions released over 48 h does not. Specifically, transcriptomic analysis using DAVID indicated significant enrichment (Benjamini-adjusted p ≤0.0.5) in LCO-exposed animals for changes in pathways involved in the cellular response to starvation (25 genes), mitochondrial function (70 genes), ATP-binding (70 genes), oxidative phosphorylation (53 genes), NADH dehydrogenase activity (12 genes), and protein biosynthesis (40 genes). Metabolomic analysis using MetaboAnalyst indicated significant enrichment (γ-adjusted p <0.1) for changes in amino acid metabolism (19 metabolites) and starch, sucrose, and galactose metabolism (7 metabolites). Overlap of significantly impacted pathways by RNA-Seq and metabolomics suggests amino acid breakdown and increased sugar import for energy production. Results indicate that LCO-exposed Daphnia respond to energy starvation by altering metabolic pathways, both at the gene expression and metabolite levels. These results support altered energy production as a sensitive nanotoxicity adverse outcome for LCO exposure and suggest negative impacts on energy metabolism as an important avenue for future studies of nanotoxicity, including for other biological systems and for metal oxide nanomaterials more broadly.