Repeated pulmonary exposures to zinc ions enhance inflammatory responses to subsequent metal exposures
| Autor: | Joseph D. Brain, Priscila de Moura Queiroz, Ramon M. Molina, Sylvia Rodrigues, Thomas C. Donaghey, Christa Watson-Wright |
|---|---|
| Rok vydání: | 2018 |
| Předmět: |
Pulmonary and Respiratory Medicine
medicine.medical_treatment Clinical Biochemistry Physiology Inflammation Lung injury medicine.disease_cause Article 03 medical and health sciences chemistry.chemical_compound 0302 clinical medicine Chlorides Air Pollution Medicine Animals 030212 general & internal medicine Dosing Molecular Biology Saline Sensitization Inhalation Exposure medicine.diagnostic_test business.industry Glutathione Cerium Pneumonia 030210 environmental & occupational health Rats Oxidative Stress medicine.anatomical_structure Bronchoalveolar lavage chemistry Metals Zinc Compounds medicine.symptom business Oxidative stress |
| Zdroj: | Experimental lung research. 44(4-5) |
| ISSN: | 1521-0499 |
| Popis: | AIM OF STUDY: Metal contaminants contribute to adverse human health effects via acute and chronic exposures. Acute metal exposures followed by prolonged secondary metal exposures may elicit exaggerated inflammatory responses in certain individuals. The aim of this study is to determine whether repeated pulmonary exposures to zinc chloride (ZnCl(2)) alters subsequent responses to zinc or cerium exposures. MATERIALS AND METHODS: Rats were intratracheally (IT) instilled with physiologic saline (n=24) or 0.05 mg/kg ZnCl(2) (n=16) twice weekly for 4 weeks. Four days after last dosing, the saline group was divided into 3 subgroups, each IT-instilled with either saline, ZnCl(2) or CeCl(3) (both at 0.1 mg/kg). The ZnCl(2) pre-instilled rats were divided into 2 subgroups, each instilled with 0.1 mg/kg ZnCl(2) or CeCl(3). Biomarkers of lung injury/inflammation were assessed in bronchoalveolar lavage (BAL) fluid collected 24 hours later. Oxidative stress was evaluated as total and reduced glutathione in BAL. RESULTS: Increases in inflammatory cells, LDH, albumin, leptin, MCP-1, IP-10, fractalkine, TNFα and RANTES were observed in rats instilled with multiple PBS and then with 0.1 mg/kg ZnCl(2) and CeCl(3). However, rats pre-exposed repeatedly to 0.05 mg/kg ZnCl(2) and then challenged with 0.1 mg/kg ZnCl(2) or CeCl(3) showed even more eosinophils, lymphocytes, and increased concentrations of hemoglobin and MIP-1α. Significant reduction in GSH/GSSG ratios in BAL in response to all ZnCl(2) or CeCl(3) exposures indicated oxidative stress. CONCLUSION: Previous exposure to zinc ions increases responsiveness to subsequent exposures to zinc and cerium ions. These findings suggest enhanced sensitization possibly due to a reduction in antioxidant defenses. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|
| Nepřihlášeným uživatelům se plný text nezobrazuje | K zobrazení výsledku je třeba se přihlásit. |