Unknown,Transcriptomics,Genomics,Proteomics

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Lungs of mice exposed to subtoxic doses of nano-titanium dioxide particles by inhalation

ABSTRACT: 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 Female C57BL/6 mice were exposed to 40 mg nanoTiO2/m3 for one hour/day for 11 consecutive days and were sacrificed 5 days following the last exposure. Left lung lobes and liver were removed and flash frozen. Total RNA was isolated from a small random part of the frozen lung and liver and was hybridized against universal mouse reference RNA to Agilent Oligo DNA microarrays (Agilent Technologies) containing 44,000 transcripts. Microarrays were normalized using a global LOWESS approach and analyzed by MAANOVA 2.0 and SAM. Microarray results were validated by real time RT-PCR. Impact of alteration in expression of select genes was further validated by analysing their total protein levels in lung tissue homogenates.

ORGANISM(S): Mus musculus

SUBMITTER: Andrew Williams

PROVIDER: E-GEOD-19487 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress

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Lungs of mice exposed to subtoxic doses of nano-titanium dioxide particles by inhalation

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