Lung production of platelet-activating factor acetylhydrolase in oleic acid-induced acute lung injury.
Platelet-activating factor (PAF) is a proinflammatory mediator that plays a central role in acute lung injury (ALI). PAF- acetylhydrolases (PAF-AHs) terminate PAF's signals and regulate inflammation. In this study, we describe the kinetics of plasma and bronchoalveolar lavage (BAL) PAF-AH in the early phase of ALI. Six pigs with oleic acid induced ALI and two healthy controls were studied. Plasma and BAL samples were collected every 2h and immunohistochemical analysis of PAF-AH was performed in lung tissues. PAF-AH activity in BAL was increased at the end of the experiment (BAL PAF-AH Time 0=0.001+/-0.001 nmol/ml/min/g vs Time 6=0.031+/-0.018 nmol/ml/min/g, p=0.04) while plasma activity was not altered. We observed increased PAF-AH staining of macrophages and epithelial cells in the lungs of animals with ALI but not in healthy controls. Our data suggest that increases in PAF-AH levels are, in part, a result of alveolar production. PAF-AH may represent a modulatory strategy to counteract the excessive pro-inflammatory effects of PAF and PAF-like lipids in lung inflammation.
Salluh
Jorge I
JI
Immunopharmacology Laboratory, Department of Physiology and Pharmacodynamics, Fundação Oswaldo Cruz, Rio de Janeiro, RJ, Brazil. jorgesalluh@yahoo.com.br
Pino
Alexandre V
AV
Silva
Adriana R
AR
Gomes
Rachel N
RN
Souza
Heitor S
HS
e Silva
Jose Roberto Lapa
JR
Jandre
Frederico C
FC
Giannella-Neto
Antonio
A
Zimmerman
Guy A
GA
Stafforini
Diana M
DM
Prescott
Stephen M
SM
Castro-Faria-Neto
Hugo C
HC
Bozza
Patrícia T
PT
Bozza
Fernando A
FA
D043203:1-Alkyl-2-acetylglycerophosphocholine Esterase / Q000096:biosynthesis* / Q000097:blood; D000818:Animals; D001992:Bronchoalveolar Lavage Fluid / Q000737:chemistry; D005260:Female; D007150:Immunohistochemistry; D007700:Kinetics; D008168:Lung / Q000201:enzymology* / Q000378:metabolism; D019301:Oleic Acid; D012128:Respiratory Distress Syndrome / Q000139:chemically induced / Q000201:enzymology*; D013552:Swine; D013997:Time Factors
D019301:Oleic Acid; D043203:1-Alkyl-2-acetylglycerophosphocholine Esterase