PT  - JOURNAL ARTICLE
AU  - Stephan J. Schliessmann
AU  - Sanja Cicko
AU  - Jan Thomassen
AU  - Timur Anlasik
AU  - Tobias Müller
AU  - Marco Idzko
AU  - Gernot Zissel
AU  - Stephan U. Sixt
TI  - Acute smoke exposure decreases bronchial extracellular proteasome concentration
DP  - 2011 Sep 01
TA  - European Respiratory Journal
PG  - p737
VI  - 38
IP  - Suppl 55
4099  - http://erj.ersjournals.com/content/38/Suppl_55/p737.short
4100  - http://erj.ersjournals.com/content/38/Suppl_55/p737.full
SO  - Eur Respir J2011 Sep 01; 38
AB  - Existence of repair mechanisms resulting in bronchial and alveolar protein degradation induced by smoke exposure are largely unknown.In the alveolar space the presence of an extracellular, biologically active 20S proteasome is recently reported [1,2]. The proteasome is involved in protein degradation and is able to degrade proteins at a high rate, possibly to minimize oncotic pressure [1].We tested whether the 20S proteasome in the bronchoalveolar space of healthy subjects is influenced by inhalation of tobacco smoke.Twelve healthy adult subjects underwent bronchoalveolar lavage (BAL) before and after cigarette smoking. To separate bronchiolar and alveolar proteasome concentration, first and second portion of lavage fluid were evaluated separately. Extracellular proteasome concentration was measured by an established in-house ELISA [2] targeting the 20S proteasome subunit a6 (HC2) in cell-free BAL fluid. For statistical evaluation the Wilcoxon signed rank test was applied.Acute smoke induces a significant decrease in extracellular 20S proteasome concentration in the bronchiolar space (94±55 to 65±50 ng/mL; p<0.05), but no change in the alveolar space (87±48 to 93±55 ng/mL).Unchanged proteasome concentration in the alveolar fluid showed no artificial elution of the proteasomes by the pre-smoking lavage.Tobacco smoke inhalation reduces the concentration of extracellular proteasome in the bronchial space and suggests less bronchiolar protein degradation in the acute phase after smoke exposure.References:1. Sixt, S.U. et al. Am J Physiol Lung Cell Mol Physiol 2007; 292:L1280-8.2. Sixt, S.U. et al. Am J Respir Crit Care Med 2009; 179:1098-106.