Exposure to persistent ligands of aryl hydrocarbon receptor (AhR) has been found to cause lung cancer in experimental animals, and lung adenocarcinomas are often associated with enhanced AhR expression and aberrant AhR activation. In order to better understand the action of toxic AhR ligands in lung epithelial cells, we performed global gene expression profiling and analyze TCDD-induced changes in A549 transcriptome, both sensitive and non-sensitive to CH223191 co-treatment. Comparison of our data with results from previously reported microarray and ChIP-seq experiments enabled us to identify candidate genes, which expression status reflects exposure of lung cancer cells to TCDD, and to predict processes, pathways (e.g. ER stress, Wnt/β-cat, IFNɣ, EGFR/Erbb1), putative TFs (e.g. STAT, AP1, E2F1, TCF4), which may be implicated in adaptive response of lung cells to TCDD-induced AhR activation. Importantly, TCDD-like expression fingerprint of selected genes was observed also in A549 cells exposed acutely to both toxic (benzo[a]pyrene, benzo[k]fluoranthene) and endogenous AhR ligands (2-(1H-Indol-3-ylcarbonyl)-4-thiazolecarboxylic acid methyl ester and 6-formylindolo[3,2-b]carbazole). Overall, our results suggest novel cellular candidates, which could help to improve monitoring of AhR-dependent transcriptional activity during acute exposure of lung cells to distinct types of environmental pollutants.
- MeSH
- aktivace transkripce účinky léků MeSH
- azosloučeniny toxicita MeSH
- benzopyren toxicita MeSH
- buňky A549 MeSH
- časové faktory MeSH
- fluoreny toxicita MeSH
- genetická transkripce účinky léků MeSH
- genové regulační sítě účinky léků MeSH
- indoly toxicita MeSH
- karbazoly toxicita MeSH
- látky znečišťující životní prostředí toxicita MeSH
- lidé MeSH
- ligandy MeSH
- nádory plic genetika metabolismus MeSH
- polychlorované dibenzodioxiny toxicita MeSH
- pyrazoly toxicita MeSH
- receptory aromatických uhlovodíků agonisté metabolismus MeSH
- regulace genové exprese u nádorů účinky léků MeSH
- sekvenční analýza hybridizací s uspořádaným souborem oligonukleotidů MeSH
- signální transdukce účinky léků MeSH
- stanovení celkové genové exprese metody MeSH
- thiazoly toxicita MeSH
- transkripční faktory bHLH agonisté metabolismus MeSH
- transkriptom účinky léků MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
OBJECTIVES: The generation of reactive oxygen species (ROS) by phagocytes is one of the irreplaceable microbicidal tools of innate immunity. It has been reported in our previous studies that short-term treatment by carvedilol ex vivo inhibits ROS generation. The purpose of this study was to investigate the long-term effect of carvedilol on phagocytes. METHODS: Human leukemia HL-60 cells differentiated into granulocyte-like cells were used as the model. Final concentrations of carvedilol were 0.1-100 micromol/l. The production of ROS by HL-60 cells was measured using luminol-enhanced chemiluminescence (CL). RESULTS: Carvedilol in concentrations 0.1-10 micromol/l did not exhibit any toxic effect on cells (measured using bioluminescent bacteria Photorhabdus luminescens subsp. thracensis). One hour's treatment with 10 micromol/l carvedilol significantly decreased both spontaneous and activated CL of cells. Conversely, no inhibitory effects on CL were observed in 10 micromol/l carvedilol after 48 h incubation; lower concentrations of carvedilol even slightly increased the CL activity of HL-60 cells. A significant increase in spontaneous CL activity was detected in cells incubated with 10 micromol/l carvedilol in comparison with the control. Powerful antioxidative properties of carvedilol against peroxyl radical (ORAC assay) were proved. No scavenging of nitric oxide (electrochemical method) was observed. CONCLUSIONS: Long-term influence of carvedilol can induce an increase in the generation of phagocyte-derived ROS and potentially also other inflammatory mediators. The increased ROS production is compensated for by antioxidative properties of carvedilol although the increased production of inflammatory mediators could affect the proper function of immune system.
- MeSH
- adenosintrifosfát metabolismus MeSH
- beta blokátory farmakologie toxicita MeSH
- buněčná diferenciace účinky léků MeSH
- fagocyty účinky léků MeSH
- fluorometrie MeSH
- granulocyty účinky léků MeSH
- HL-60 buňky MeSH
- karbazoly farmakologie toxicita MeSH
- lidé MeSH
- luminiscence MeSH
- oxid dusnatý metabolismus MeSH
- peroxidy metabolismus MeSH
- proliferace buněk účinky léků MeSH
- propanolaminy farmakologie toxicita MeSH
- reaktivní formy kyslíku metabolismus MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- práce podpořená grantem MeSH
Immature liver progenitor cells have been suggested to be an important target of hepatotoxins and hepatocarcinogens. The goal of the present study was to assess the impact of 7H-dibenzo[c,g]carbazole (DBC) and its tissue-specific carcinogenic N-methyl (N-MeDBC) and 5,9-dimethyl (DiMeDBC) derivatives on rat liver epithelial WB-F344 cells, in vitro model of liver progenitor cells. We investigated the cellular events associated with both tumor initiation and promotion, such as activation of aryl hydrocarbon receptor (AhR), changes in expression of enzymes involved in metabolic activation of DBC and its derivatives, effects on cell cycle, cell proliferation/apoptosis and inhibition of gap junctional intercellular communication (GJIC). N-MeDBC, a tissue-specific sarcomagen, was only a weak inhibitor of GJIC or inducer of AhR-mediated activity, and it did not affect either cell proliferation or apoptosis. DBC was efficient GJIC inhibitor, while DiMeDBC manifested the strongest AhR inducing activity. Accordingly, DiMeDBC was also the most potent inducer of cytochrome P450 1A1 (CYP1A1) and CYP1A2 expression among the three compounds tested. Both DBC and DiMeDBC induced expression of CYP1B1 and aldo-keto reductase 1C9 (AKR1C9). N-MeDBC failed to significantly upregulate CYP1A1/2 and it only moderately increased CYP1B1 or AKR1C9. Only the potent liver carcinogens, DBC and DiMeDBC, caused a significant increase of p53 phosphorylation at Ser15, an increased accumulation of cells in S-phase and apoptosis at micromolar concentrations. In addition, DiMeDBC was found to stimulate cell proliferation of contact-inhibited WB-F344 cells at 1 microM concentration, which is a mode of action that might further contribute to its hepatocarcinogenicity. The present data seem to suggest that the AhR activation, induction of enzymes involved in metabolic activation, inhibition of GJIC or stimulation of cell proliferation might all contribute to the hepatocarcinogenic effects of DBC and DiMeDBC.
- MeSH
- aromatické hydroxylasy genetika MeSH
- buněčná smrt účinky léků MeSH
- cytochrom P-450 CYP1A1 genetika MeSH
- cytochrom P-450 CYP1A2 genetika MeSH
- DNA primery MeSH
- epitelové buňky patologie účinky léků MeSH
- financování organizované MeSH
- játra cytologie účinky léků MeSH
- karbazoly toxicita MeSH
- karcinogeny toxicita MeSH
- krysa rodu rattus MeSH
- metylace MeSH
- molekulární struktura MeSH
- mutageny MeSH
- polymerázová řetězová reakce s reverzní transkripcí MeSH
- potkani inbrední F344 MeSH
- sekvence nukleotidů MeSH
- zvířata MeSH
- Check Tag
- krysa rodu rattus MeSH
- zvířata MeSH
