Project description:The toxicity and toxicogenomics of selected anatase and rutile nanoparticles (NP) and bulk titanium dioxide (TiO2) particles were evaluated in the soil nematode Caenorhabditis elegans. Results indicated that bulk or nano-TiO2 particles were slightly toxic to soil nematode C. elegans, as measured by reproduction EC50 values ranging from 4 to 32 mg/L. Whole-genome microarray results indicated that the regulation of glutathione-S-transferase gst-3, cytochrome P450 cypp33-c11, stress resistance regulator scl-1, oxidoreductase wah-1, and embryonic development pod-2 genes were significantly affected by nano-sized and bulk TiO2 particles. More specifically, it was determined that anatase particles exerted a greater effect on metabolic pathways, whereas rutile particles had a greater effect on developmental processes. The up-regulation of the pod-2 gene corroborated the phenotypic effect observed in the reproduction test. Our results demonstrated that C. elegans is a good genomic model for nano-TiO2 toxicity assessment.
2014-07-17 | GSE59470 | GEO
Project description:soil microbial ecology response to Nano particles
Project description:RNA microarray was performed to evaluate the efficacy of silicon nano-particles on renal transcriptomes of rats against ischemia reperfusion injury. We compared the transcriptomes of ischemia reperfusion injury model rats with or without oral administration of silicon nano-particles. We also tried to check whether the oral silicon nano-particles intake downregulated the biological processes related to oxidative stress.
Project description:Acute phase reactants serum amyloid A-1, 3 and micro RNA-135b, -449a, and -1 are induced in lungs of mice exposed to subtoxic doses of nano-titanium dioxide particles by inhalation In the present study we investigate pulmonary mRNA and miRNA profiles of mice exposed to subtoxic dose of nano-titanium dioxide particles by inhalation. We show dramatic induction of acute phase reactants, chemoattractants, immune and host defence related genes. We also demonstrate for the first time changes in miRNA profiles in the lungs in response to nanoTiO2. Keywords: Toxicology, disease state analysis, biomarkers of health effects
Project description:Amorphous calcium carbonate (ACC) is a non-crystalline form of calcium carbonate, which is composed of aggregated nano-size primary particles. Here, we wanted to evaluate how ACC affects gene expression in a human lung cancer cell line (A549).
Project description:To screen for novel toxicological endpoints of nano-particles, we conducted an in vitro expression profiling study using human lung epithelial cells (A549). To identify effects that are specific to size or chemical origin, we compared gene expression of A549 cells treated with nano-sized and micro-sized particulates of two chemical origins (carbon and silica) to the control (untreated) cells.
Project description:The toxicity of silver and zinc oxide nanoparticles is hypothesised to be mediated by dissolved metal ions and cerium dioxide nanoparticles (CeO2 NPs) are hypothesised to induce toxicity specifically by oxidative stress dependant on their surface redox state. To test these hypotheses, RNAseq was applied to characterise the molecular responses of cells to metal nanoparticle and metal ion exposures. The human epithelial lung carcinoma cell line A549 was exposed to different CeO2 NPs with different surface charges, micron-sized and nano-sized silver particles and silver ions, micron-sized and nano-sized zinc oxide particles and zinc ions, or control conditions, for 1 hour, 6 hours and 24 hours. Concentrations were the lower of either EC20 or 128 micrograms/mL. Transcriptional responses were characterised by RNAseq transcriptomics using an Illumina HiSeq2500 .
Project description:Using a macrophage cell line, we demonstrate the ability of amorphous silica particles to stimulate inflammatory protein secretion and induce cytotoxicity. Whole genome microarray analysis of early gene expression changes induced by 10nm and 500nm particles showed that the magnitude of change for the majority of genes correlated more tightly with particle surface area than either particle mass or number. Gene expression changes that were size-specific were also identified, however the overall biological processes represented by all gene expression changes were nearly identical, irrespective of particle diameter. Our results suggest that on an equivalent nominal surface area basis, common biological modes of action are expected for nano- and supranano-sized silica particles. Keywords: Dose-response study
