Preferential induction of CYP1A1 and CYP1B1 in CCSP-positive cells
| Autor: | Louis W. Chang, Pinpin Lin, Ya-Hsin Cheng, Wen-Tin Tsai, Han Chang, Ming-Xian Tsai |
|---|---|
| Rok vydání: | 2005 |
| Předmět: |
Male
Cell type Polychlorinated Dibenzodioxins CYP1B1 Immunocytochemistry Gene Expression Respiratory Mucosa Toxicology Rats Sprague-Dawley Western blot medicine Benzo(a)pyrene Cytochrome P-450 CYP1A1 Animals Humans Uteroglobin RNA Messenger Receptor Lung medicine.diagnostic_test biology Reverse Transcriptase Polymerase Chain Reaction Epithelial Cells respiratory system Aryl hydrocarbon receptor Molecular biology In vitro respiratory tract diseases Rats Cell culture Enzyme Induction Cytochrome P-450 CYP1B1 biology.protein Aryl Hydrocarbon Hydroxylases |
| Zdroj: | Toxicological sciences : an official journal of the Society of Toxicology. 89(1) |
| ISSN: | 1096-6080 |
| Popis: | Both benzo[a]pyrene (BaP) and 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) are potent ligands of aryl hydrocarbon receptors (AhR). Although animal studies indicate that both compounds induce pathological changes in the peripheral lung, the specific cell type involved remains unclear. Clara cells, expressing Clara cell specific protein (CCSP) and abundant in cytochrome P450, are nonciliated bronchiolar epithelial cells in the peripheral lung. Here we explore the hypothesis that CCSP-positive Clara cells are highly responsive to AhR ligands and are the primary cell type involved in BaP- and TCDD-induced toxicities. The responsiveness to AhR ligands was evaluated by measuring the respective mRNA and protein levels of cytochrome P450 1A1 (CYP1A1) and 1B1 (CYP1B1) using real-time RT-PCR and immunocytochemistry assays. Two in vitro models were used: primary cultures of human small airway epithelial (SAE) cells and rat lung slice cultures. In the presence of calcium, human SAE cells differentiated into CCSP-positive cells. BaP- and TCDD-induced mRNA and protein levels of CYP1A1 and CYP1B1 levels were significantly elevated in CCSP-positive cell cultures. Similarly, AhR mRNA and protein levels were increased in CCSP-positive cell cultures, as determined by real-time RT-PCR and Western blot analysis. When rat lung slice cultures were treated with BaP or TCDD for 24 h, CYP1A1 and CYP1B1 proteins were strongly induced in Clara cells. These results indicate that, in the peripheral lung of both rats and humans, CCSP-positive cells (Clara cells) may be more sensitive to AhR ligands than other cell types. |
| Databáze: | OpenAIRE |
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