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The Toxicologist - Society of Toxicology

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characterized mouse hepatoma cell line, Hepa1c1c7, was chosen as a cellular<br />

model. In a first step, two concentrations (50 nM and 5 μM) and four time points<br />

(2, 4, 12 and 24 h) were used for comprehensive transcriptome analysis. Thus,<br />

RNA was isolated and applied to Affymetrix exon arrays. Analysis showed a total <strong>of</strong><br />

2000 genes to be significantly regulated either by concentration or by time and<br />

concentration. About 89 regulated genes are transcription factors, raising the possibility<br />

<strong>of</strong> transcription factor cross-talk in BaP signalling. Genes related to transcription/translation,<br />

cell adhesion and DNA repair are among the regulated genes.<br />

Some <strong>of</strong> the robustly regulated genes are those encoding for cytochrome P450 enzymes<br />

and the TCDD-inducible poly(ADP-ribose) polymerase, Tiparp. <strong>The</strong>se are<br />

known targets <strong>of</strong> the aryl hydrocarbon receptor (AhR), which is activated by BaP.<br />

To start to link these regulations in the transcriptome to the cellular phenotype,<br />

changes in cell number were explored over 48 hours <strong>of</strong> exposure to up to 5 μM BaP.<br />

Indeed, cell number increased over time with no apparent differences up to 500<br />

nM BaP. At 5 μM BaP, however, cell number stayed constant over the entire exposure<br />

time, thereby indicating disruption <strong>of</strong> the cell cycle. Our next goal is to identify<br />

how cellular functions change if Tiparp is knocked down.<br />

1600 TRANSCRIPTOMICS ANALYSIS OF NANOPARTICLE-<br />

CONTAINING HAIR DYES.<br />

D. A. Sarigiannis, G. Cimino Reale, E. Marafante, B. Casati, R. Brustio and A.<br />

Collotta. Institute for Health and Consumer Protection, European Commission - Joint<br />

Research Centre, Ispra, Varese, Italy. Sponsor: L. Birnbaum.<br />

<strong>The</strong> overall objective <strong>of</strong> this study was to explore the applicability <strong>of</strong> transcriptomics<br />

for risk assessment <strong>of</strong> mixtures <strong>of</strong> chemicals in consumer products such as<br />

cosmetics and in particular hair dyes so as to develop a systems toxicology framework<br />

for consumer product risk assessment. In particular, this approach is expected<br />

to identify genetic biomarkers <strong>of</strong> exposure and early effects related to chronic exposure<br />

to low doses <strong>of</strong> commercially relevant hair dye preparations. According to the<br />

study design these biomarkers would be identified through the use <strong>of</strong> whole<br />

genome gene expression micro-arrays and corroborated with quantitative PCR<br />

using micro-fluidic cards for specific gene families and biological processes.<br />

<strong>The</strong> study comprised in vivo analysis on urinary bladder and on skin from rat for<br />

the identification <strong>of</strong> gene expression patterns in target organs, and quantitative<br />

PCR using micro-fluidic cards for specific inflammation genes.<br />

Comparison was made with formulations including reactants usually applied in the<br />

products application (e.g. p-phenylendiamine and atninophenol). Three different<br />

formulations were tested: the active substance (p-phenylendiamine, PPD); a commercial<br />

hair dye formulation using PPD as its principal active ingredient (HD); a<br />

similar commercial hair dye using nanoparticle-bound PPD for better dyeing and<br />

duration effects (HD nano).<br />

<strong>The</strong> chemicals were applied both on the skin and on the hair <strong>of</strong> the treated rats. A<br />

number <strong>of</strong> biological processes that were significantly induced compared to the<br />

controls after treatment are characteristic <strong>of</strong> specific products. Blood circulation,<br />

clotting and vesicular transport were induced by HD nano only, suggesting that the<br />

overall chemical mixture in the HD nano preparation behaves differently than the<br />

conventional HD preparation. Blood circulation features should be tested when assessing<br />

the toxic potency <strong>of</strong> HD nano. Moreover, several metabolic processes were<br />

induced after treatment with HD nano, including fatty acid, cholesterol, amino<br />

acid and nitrogen metabolism.<br />

1601 A TOXICOGENOMIC COMPARISON OF PRIMARY<br />

VERSUS PHOTOCHEMICALLY ALTERED AIR<br />

POLLUTANTS IN HUMAN LUNG CELLS.<br />

J. E. Rager 1 , K. G. Sexton 1 , L. Smeester 1 , I. Jaspers 2 and R. C. Fry 1 .<br />

1 Environmental Sciences and Engineering, Gillings School <strong>of</strong> Global Public Health,<br />

University <strong>of</strong> North Carolina, Chapel Hill, NC and 2 Center for Environmental<br />

Medicine, Asthma, and Lung Biology, School <strong>of</strong> Medicine, University <strong>of</strong> North<br />

Carolina, Chapel Hill, NC.<br />

Outdoor air pollution contributes significantly to global increases in mortality, particularly<br />

within urban environments. Studies have investigated lung responses<br />

caused by single pollutants, such as individual gases or particulate matter. <strong>The</strong>re is,<br />

however, limited knowledge on the mechanisms underlying health effects resulting<br />

from exposure to pollutant mixtures. Toxicogenomic analyses can increase our<br />

mechanistic understanding through the study <strong>of</strong> gene expression alterations and associated<br />

molecular pathways. Here, we set out to compare and contrast responses <strong>of</strong><br />

lung cells exposed to primary pollutants relative to photochemically altered (PCA)<br />

pollutant mixtures found in urban atmospheres. We hypothesized that lung cells<br />

exposed to PCA pollutants would show increased modulation <strong>of</strong> inflammatory-associated<br />

genes and pathways relative to primary air pollutants. Human lung epithelial<br />

cells were exposed to either primary or PCA air mixtures. mRNA expression<br />

changes were assessed using microarrays and confirmed using RT-PCR on a subset<br />

344 SOT 2011 ANNUAL MEETING<br />

<strong>of</strong> genes. <strong>The</strong>re was a massive difference in cell response with primary air pollutants<br />

altering the expression levels <strong>of</strong> 19 genes, while PCA pollutants altered 709 genes.<br />

Functional and molecular analyses <strong>of</strong> the altered genes showed that pollutant exposure<br />

modifies the signaling <strong>of</strong> pathways associated with cancer and inflammation.<br />

To confirm the altered inflammatory response, protein was collected and interleukin-8<br />

was measured at significantly increased levels. Our study shows for the first<br />

time that photochemically produced secondary pollutants initiate significantly<br />

more robust changes in gene expression patterns in comparison to primary components<br />

<strong>of</strong> air pollution. This difference may, in part, explain the health effects related<br />

to air pollutant exposure.<br />

1602 UNCOVERING TRANSCRIPTIONAL REGULATORS OF<br />

KIDNEY INJURY MOLECULE-1 IN CISPLATIN-<br />

INDUCED KIDNEY TOXICITY.<br />

M. P. Wagoner, J. Milano, D. Brott, D. Thurman, Y. Dragan, L. B. Kinter and<br />

B. Jeffy. Safety Assessment U.S., AstraZeneca, Wilmington, DE.<br />

Kidney Injury Molecule 1 (KIM-1) is emerging as an important biomarker for drug<br />

induced histologically defined renal tubular injury (DIKI), as it is a more sensitive<br />

and more accurate measure <strong>of</strong> DIKI than current clinically available tests.<br />

Nephrotoxic compounds such as cisplatin or gentamicin increase both tubular<br />

KIM-1 mRNA and urinary KIM-1 protein. While it is understood that urinary<br />

KIM-1 protein levels are driven by increased KIM-1 transcription, the transcription<br />

factors responsible are as <strong>of</strong> yet unknown. We used an acute dose model <strong>of</strong> cisplatin<br />

induced nephrotoxicity to identify putative KIM-1-inducing transcription factors,<br />

examining kidney transcriptional pr<strong>of</strong>iles from 54 rats from 3 different strains following<br />

varying doses <strong>of</strong> cisplatin. Genes induced by cisplatin in a manner resembling<br />

KIM-1 expression patterns were identified implying that these genes may<br />

have common transcriptional regulators (Pearson correlation p

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