TY - JOUR
T1 - Impairment of airway mucociliary transport by Pseudomonas aeruginosa products
T2 - Role of oxygen radicals
AU - Seybold, Z. V.
AU - Abraham, W. M.
AU - Gazeroglu, H.
AU - Wanner, A.
PY - 1992
Y1 - 1992
N2 - We previously showed that the supernatant of a Pseudomonas aeruginosa (PA) culture and its constituents pyocyanin and 1-hydroxyphenazine inhibit ciliary activity of dispersed tracheal epithelial cells in vitro via the generation of oxygen radicals by phagocytes. In the present study, we wished to determine if tracheal mucus velocity (TMV) is also impaired by PA supernatant and if oxygen radicals have a mediating role. In conscious sheep, TMV (measured with a radiographic method) was determined before and serially following aerosol challenge with the cell-free supernatant of a PA culture or unconditioned culture medium (control). TMV decreased from a mean (± SEM) baseline of 6.7 ± 1.1 mm/min (n = 6) by 29, 35, and 25% at 0.5, 3, and 24 h after challenge, respectively (p < 0.05), and returned to baseline 1 wk later (-6%, p = NS). Control medium had no effect on TMV (maximum decrease by 15% at 0.5 h). Aerosolized catalase blunted the effect of PA supernatant on TMV. To determine if the impairment of TMV involved ciliary inhibition, tissues were mounted in a chamber and ciliary beat frequency (CBF) and surface liquid velocity (SLV) were measured with a microscopic method. PA supernatant decreased both CBF (maximum mean decrease 12%; n = 5, p < 0.05) and SLV (maximum mean decrease 78%; n = 5, p < 0.05) in a dose-dependent fashion, with a correlation between the two parameters; these effects were blocked by catalase. We conclude that (1) short-term exposure to PA products decrease airway mucociliary clearance in vivo in part by a pathway involving oxygen radicals, (2) the impairment persists for at least 24 h but less than a week, and (3) cilioinhibition has a role in the PA-induced decrease in mucociliary clearance.
AB - We previously showed that the supernatant of a Pseudomonas aeruginosa (PA) culture and its constituents pyocyanin and 1-hydroxyphenazine inhibit ciliary activity of dispersed tracheal epithelial cells in vitro via the generation of oxygen radicals by phagocytes. In the present study, we wished to determine if tracheal mucus velocity (TMV) is also impaired by PA supernatant and if oxygen radicals have a mediating role. In conscious sheep, TMV (measured with a radiographic method) was determined before and serially following aerosol challenge with the cell-free supernatant of a PA culture or unconditioned culture medium (control). TMV decreased from a mean (± SEM) baseline of 6.7 ± 1.1 mm/min (n = 6) by 29, 35, and 25% at 0.5, 3, and 24 h after challenge, respectively (p < 0.05), and returned to baseline 1 wk later (-6%, p = NS). Control medium had no effect on TMV (maximum decrease by 15% at 0.5 h). Aerosolized catalase blunted the effect of PA supernatant on TMV. To determine if the impairment of TMV involved ciliary inhibition, tissues were mounted in a chamber and ciliary beat frequency (CBF) and surface liquid velocity (SLV) were measured with a microscopic method. PA supernatant decreased both CBF (maximum mean decrease 12%; n = 5, p < 0.05) and SLV (maximum mean decrease 78%; n = 5, p < 0.05) in a dose-dependent fashion, with a correlation between the two parameters; these effects were blocked by catalase. We conclude that (1) short-term exposure to PA products decrease airway mucociliary clearance in vivo in part by a pathway involving oxygen radicals, (2) the impairment persists for at least 24 h but less than a week, and (3) cilioinhibition has a role in the PA-induced decrease in mucociliary clearance.
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U2 - 10.1164/ajrccm/146.5_Pt_1.1173
DO - 10.1164/ajrccm/146.5_Pt_1.1173
M3 - Article
C2 - 1443866
AN - SCOPUS:0026440863
VL - 146
SP - 1173
EP - 1176
JO - American Journal of Respiratory and Critical Care Medicine
JF - American Journal of Respiratory and Critical Care Medicine
SN - 1073-449X
IS - 5
ER -