Zinc is a common metal in most ambient particulate matter (PM), and has been proposed to be a causative component in PM-induced adverse cardiovascular health effects. Zinc is also an essential metal and has the potential to induce many physiological and nonphysiological changes. Most toxicological studies employ high levels of zinc. We hypothesized that subchronic inhalation of environmentally relevant levels of zinc would cause cardiac changes in healthy rats. To address this question, healthy male WKY rats (12 wks age) were exposed via nose only inhalation to filtered air or 10, 30 or 100 ug/m3 of aerosolized Zn in sulfate form, 5 h/d, 3 d/wk for 16 wks. Necropsies occurred 48 h after the last exposure to ensure effects were due to chronic exposure rather than the last exposure. No significant changes were observed in neutrophil or macrophage count, total lavageable cells, or enzyme activity levels (lactate dehydrogenase, n-acetyl ?-D-glucosaminidase, ?-glutamyl transferase) in bronchoalveolar lavage fluid, indicating minimal pulmonary effect. In the heart, cytosolic glutathione peroxidase activity decreased, while mitochondrial ferritin levels increased and succinate dehydrogenase activity decreased, suggesting a mitochondria-specific effect. Although no cardiac pathology was seen, cardiac gene array analysis indicated changes in genes involved in cell signaling, a pattern concordant with known zinc effects. These data indicate that inhalation of zinc at environmentally relevant levels may induce cardiac effects. While changes are small in healthy rats, these may be especially relevant in individuals with pre-existent cardiovascular disease.
Subchronic inhalation of zinc sulfate induces cardiac changes in healthy rats.
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View SamplesDEP exposure is linked to increases in cardiovascular effects. This effect is enhanced in individuals with pre-existing disease. Animal models of cardiovascular disease are used to study this susceptibility. The heart is rich in mitochondria, which produce high levels of free radicals, leading to inactivation of tricarboxylic acid cycle enzymes. We hypothesized that a 4-wk DEP inhalation would result in strain-related structural impairment of cardiac mitochondria and changes in these enzyme activities in WKY and SHR. Male rats (12-14 wks age) were exposed whole body to air or 0.5 or 2.0 mg/m3 DEP for 6h/d, 5 d/wk for 4 wks. Neutrophilic influx was noted in the bronchoalveolar lavage fluid in both strains. A slightly lower level of baseline cardiac mitochondrial aconitase activity was seen in SHR than WKY. Aconitase activity appeared to be decreased in an exposure related manner in both strains. Significantly higher baseline levels of cardiac cytosolic ferritin and aconitase activity were seen in the SHR than WKY. No exposure-related changes were noted in either of these measures. Mitochondrial succinate and isocitrate dehydrogenase activities were not changed following DEP exposure in either strain. Transmission electron microscopy images of the heart indicated abnormalities in cardiac mitochondria of control SHR but not control WKY. No exposure related ultrastructural changes were induced by DEP in either strain. In conclusion, strain differences in cardiac biomarkers of oxidative stress and structure of mitochondria exist between SHR and WKY. DEP exposure results in small changes in cardiac mitochondrial and cytosolic markers of oxidative stress. (Abstract does not represent USEPA policy.)
One-month diesel exhaust inhalation produces hypertensive gene expression pattern in healthy rats.
Specimen part
View SamplesZinc (Zn) is a major elemental component of respirable ambient particulate matter (PM) detected often at alarming levels in urban air. Exposure to PM has been widely associated with increased cardiovascular morbidity and mortality, however, it is not known what components or sources of PM are causative. We recently demonstrated that long-term episodic inhalation of combustion PM, having similar amount of Zn found in urban PM, caused myocardial lesions in rats. We further demonstrated that a single pulmonary exposure to Zn at high concentration is associated with disturbances in cardiac mitochondrial function, ion channel regulation, calcium homeostasis, and cell signaling. Therefore, in this study we investigated the role of PM-associated Zn in cardiac injury using multiple exposure scenarios. Male Wistar-Kyoto (WKY) rats of 12-14 wks age were intratracheally exposed (once per wk x 8 or16 wks) to either (1) saline (control); (2) PM having no soluble Zn; (3) combustion PM suspension containing 14.5 ug/mg water-soluble Zn at high and (4) low dose levels, (5) the aqueous fraction of this suspension devoid of solid insoluble particulate fraction (14.5 ug/mg soluble Zn), or (6) Zn sulfate. Zn concentrations were identical in groups 3, 5 and 6. Pulmonary toxicity was apparent in all exposure groups when compared to saline as determined by recovery of cells in bronchoalveolar lavage fluid. Long-term exposure to PM with or without soluble Zn, or Zn sulfate caused distinct myocardial lesions characterized by subepicardial and randomly distributed myocardial inflammation, degeneration, and fibrosis. The lesion severity was higher in those groups receiving Zn PM. Because cardiac mitochondria are likely the primary target of inhaled metal or other absorbed PM components, we analyzed mitochondrial DNA damage using QPCR and found that all exposure groups except those exposed to PM without Zn caused variable degree of damage. Aconitase activity, sensitive to inhibition by oxidative stress was inhibited slightly but significantly in rats receiving zinc sulfate. Although modest, microarray (Affymetrix) analysis revealed expression changes in the heart reflective of effects on cell signaling, inflammation/oxidative stress, mitochondrial fatty acid metabolisms and cell cycle regulation in rats exposed to zinc sulfate. However, these changes were minimal following exposure to PM devoid of soluble metals. We demonstrate that episodic subchronic pulmonary exposure to zinc sulfate causes cardiac injury and mitochondrial DNA damage. Thus, water-soluble PM-associated zinc may be one of the PM components responsible for cardiovascular morbidity.
The role of particulate matter-associated zinc in cardiac injury in rats.
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View SamplesMurine healthy tissue samples, DCIS and invasive mammary tumors were analyzed in order to identify marker genes which show enhanced expresssion in DCIS and invasive ductal carcinomas.
Identification of early molecular markers for breast cancer.
Specimen part
View SamplesHuman healthy tissue samples, DCIS and invasive mammary tumors were analyzed in order to identify marker genes which show enhanced expresssion in DCIS and invasive ductal carcinomas.
Identification of early molecular markers for breast cancer.
Specimen part, Disease, Disease stage
View SamplesWNT-induced secreted protein 1 (WISP1/CCN4), a member of the CCN protein family, acts as a downstream factor of the canonical WNT-signaling pathway. A dysregulated expression of WISP1 often reflects its oncogenic potential by inhibition of apoptosis, a necessary form of cell death that protect cell populations for transformation into malignant phenotypes. WISP1-signaling is also known to affect proliferation and differentiation of human mesenchymal stem cells (hMSCs), which are fundamental for the constitution and maintenance of the musculoskeletal system. Our study emphasizes the importance of WISP1-signaling for cell survival of primary human cells. Therefore, we established a successful down-regulation of endogenous WISP1 transcripts through gene silencing in hMSCs. We were able to demonstrate the consequence of cell death immediately after WISP1 down-regulation took place. Bioinformatical analyses of subsequent performed microarrays from WISP1 down-regulated vs. control samples confirmed this observation. We uncovered several clusters of differential expressed genes important for cellular apoptosis induction and immuno-regulatory processes, thereby indicating TRAIL-induced and p53-mediated apoptosis as well as IFNbeta-signaling. Since all of them act as potent inhibitors for malignant cell growth, in vitro knowledge about the connection with WISP1-signaling could help to find new therapeutic approaches concerning cancerogenesis and tumor growth in musculoskeletal tissues.
WISP 1 is an important survival factor in human mesenchymal stromal cells.
Specimen part, Treatment
View SamplesPurpose: Seek for differential gene expression in vemurafenib-resistant A375 tumors vs. untreated controls to provide a rationale for resistance mechanism Methods: mRNA profiles of vemurafenib-resistant A375 tumors and untreated control tumors were generated by transcriptome sequencing of A375 melanoma bearing mice. Since our xenograft samples contain a mixture of human and mouse RNAs we mapped RNASeq reads against a hybrid human/mouse genome. We than removed reads of potential mouse origin by taking only reads that map uniquely to human chromosomes. On average 23% of reads were removed as potential mouse reads. We than took the remaining reads (on average 77% per sample) to determine the gene expression levels for each sample. Normalized expression levels of 5 resistant samples were compared to 4 untreated control samples to detect differnetially regulated genes which may contribute to vemurfenib resistance Results: Expression levels of several genes were consistently altered in all resistant samples. Expression of e.g. genes encoding SPRY2, SPRY4, DUSP6, CCND1, PIK3R3, FGFR1, EPHA4, MCL1, and IGF1R was down-regulated, whereas expression of PDGFC, VEGFC, ABCB9 and KITLG was increased. Conclusions: Our study reports several differentially expressed genes which may contribute to vemurafenib resistance in A375 tumor bearing mice Overall design: RNA sequencing of genes expressed in A375 tumors bearing mice treated with vemurafenib until in vivo resistance appeared vs. untreated A375 tumors
A Novel RAF Kinase Inhibitor with DFG-Out-Binding Mode: High Efficacy in BRAF-Mutant Tumor Xenograft Models in the Absence of Normal Tissue Hyperproliferation.
No sample metadata fields
View SamplesCyclosporin A induces expression of proapoptotic factors when cells are challenged by increased tonicity
Cyclosporin-A induced toxicity in rat renal collecting duct cells: interference with enhanced hypertonicity induced apoptosis.
Specimen part, Treatment
View SamplesIn this study we analyzed the myeloma cell contact-mediated changes on the transcriptome of skeletal precursor cells. Therefore, human mesenchymal stem cells (MSC) and osteogenic precursor cells (OPC) were co-cultured with the representative myeloma cell line INA-6 for 24 h. Afterwards, MSC and OPC were separated from INA-6 cells by fluorescence activated cell sorting. Total RNA of MSC and OPC fractions was used for whole genome array analysis.
Contact of myeloma cells induces a characteristic transcriptome signature in skeletal precursor cells -Implications for myeloma bone disease.
Sex, Age, Specimen part, Disease stage
View SamplesGenome-wide association studies (GWAS) have identified dozens of genomic loci, whose single nucleotide polymorphisms (SNPs) predispose to prostate cancer (PCa). However, the biological functions of these common genetic variants and the mechanisms to increase disease risk are largely unknown. We integrated chromatin-IP coupled sequencing (ChIP-seq) and microarray expression profiling in the TMPRSS2-ERG gene rearrangement positive DuCaP cell model with the NHGRI GWAS PCa risk SNPs catalog, in an attempt to identify disease susceptibility SNPs localized within functional androgen receptor binding sites (ARBSs). Among the 48 GWAS index SNPs and 2,702 linked SNPs defined by the 1000G project 104 were found to be localized in the AR ChIP-seq peaks. Of these risk SNPs, rs11891426 T/G in the 7th intron of its host gene melanophilin (MLPH) was found located within a putative auxiliary ARE motif, which we found enriched in the neighborhood of canonical ARE motifs. Exchange of T to G attenuated the transcriptional activity of the MLPH-ARBS in a reporter gene assay. The expression of MLPH protein in tissue samples from prostate cancer patients was significantly lower in those with the G compared to the T allele. Moreover, a significant positive correlation of AR and MLPH protein expression levels was also confirmed in tissue samples. These results unravel a hidden link between AR and a functional PCa risk SNP rs11891426, whose allele alteration affects androgen regulation of its host gene MLPH. This study shows the power of integrative studies to pin down functional risk SNPs and justifies further investigations.
Putative Prostate Cancer Risk SNP in an Androgen Receptor-Binding Site of the Melanophilin Gene Illustrates Enrichment of Risk SNPs in Androgen Receptor Target Sites.
Cell line, Treatment, Time
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