Increased oxidant resistance of alveolar epithelial type II cells. Isolated from rats following repeated exposure to cadmium aerosols
| Autor: | J.D. Eneman, B.A. Hart, C.C. Durieux-lu, Q. Gong |
|---|---|
| Rok vydání: | 1995 |
| Předmět: |
Male
Antioxidant medicine.medical_treatment Glutathione reductase Toxicology medicine.disease_cause Administration Inhalation medicine Extracellular Animals Metallothionein Aerosols Hyperoxia Glutathione Peroxidase biology Chemistry Hydrogen Peroxide General Medicine Catalase Oxidants Immunohistochemistry Molecular biology In vitro Rats Pulmonary Alveoli Glutathione Reductase Biochemistry Rats Inbred Lew biology.protein medicine.symptom Oxidative stress Cadmium |
| Zdroj: | Toxicology Letters. 81:131-139 |
| ISSN: | 0378-4274 |
| Popis: | Alveolar epithelial type II cells (AEIIC) were isolated from male Lewis rats following repeated in vivo cadmium aerosol exposure and were subsequently evaluated for their oxidant resistance in vitro. AEIIC from Cd-adapted animals removed a greater proportion of hydrogen peroxide from the extracellular milieu and incurred less oxidant-induced cytotoxicity than AEIIC from air controls. This altered response to oxidants occurred coincident with changes in cellular resistance factors. A two-fold increase in glutathione peroxidase activity and a 1.5-fold increase in the activities of glutathione reductase and catalase were observed in Cd-adapted AEIIC compared to control cells. These cells also exhibited a dramatic induction of metallothionein (MT), a thiol-rich protein known to scavenge free radicals in vitro. MT concentration increased as a function of exposure number. MT was localized within the nucleus and cytoplasm of AEIIC by immunocytochemical techniques. MT positive cells showed a wide variation of MT content, particularly in the nucleus. The biochemical and physiological features of these AEIIC may explain, in part, why animals pretreated with Cd aerosols develop cross-tolerance to hyperoxia. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|
Full Text from ScienceDirect