Bradykinin inducible receptor is essential to lipopolysaccharide-induced acute lung injury in mice.
Lipopolysaccharides from gram-negative bacteria are amongst the most common causative agents of acute lung injury, which is characterized by an inflammatory response, with cellular infiltration and the release of mediators/cytokines. There is evidence that bradykinin plays a role in lung inflammation in asthma but in other types of lung inflammation its role is less clear. In the present study we evaluated the role of the bradykinin B1 receptor in acute lung injury caused by lipopolysaccharide inhalation and the mechanisms behind bradykinin actions participating in the inflammatory response. We found that in C57Bl/6 mice, the bradykinin B1 receptor expression was up-regulated 24h after lipopolysaccharide inhalation. At this time, the number of cells and protein concentration were significantly increased in the bronchoalveolar lavage fluid and the mice developed airway hyperreactivity to methacholine. In addition, there was an increased expression of tumor necrosis factor-alpha, interleukin-1 beta and interferon-gamma and chemokines (monocytes chemotactic protein-1 and KC) in the bronchoalveolar lavage fluid and in the lung tissue. We then treated the mice with a bradykinin B1 receptor antagonist, R-954 (Ac-Orn-[Oic2, alpha-MePhe5, D-betaNal7, Ile8]desArg9-bradykinin), 30 min after lipopolysaccharide administration. We observed that this treatment prevented the airway hyperreactivity as well as the increased cellular infiltration and protein content in the bronchoalveolar lavage fluid. Moreover, R-954 inhibited the expression of cytokines/chemokines. These results implicate bradykinin, acting through B1 receptor, in the development of acute lung injury caused by lipopolysaccharide inhalation.
Laboratory of Transplantation Immunobiology, Department of Immunology, University of São Paulo, Av. Prof. Lineu Prestes, 1730, ICB IV, 05508-900, São Paulo, SP, Brazil.
Gabriela
G
Campanholle
Richardt G
RG
Landgraf
Erica
E
Borducchi
Patricia
P
Semedo
Pamela H M
PH
Wang
Mariane T
MT
Amano
Momtchilo
M
Russo
Alvaro
A
Pacheco-Silva
Sonia
S
Jancar
Niels O S
NO
Camara
D055371:Acute Lung Injury / Q000139:chemically induced / Q000378:metabolism* / Q000473:pathology / Q000517:prevention & control; D000280:Administration, Inhalation; D000818:Animals; D001920:Bradykinin / Q000008:administration & dosage / Q000031:analogs & derivatives / Q000627:therapeutic use; D065169:Bradykinin B1 Receptor Antagonists; D001992:Bronchoalveolar Lavage Fluid; D016207:Cytokines / Q000032:analysis / Q000096:biosynthesis; D004195:Disease Models, Animal; D018836:Inflammation Mediators / Q000008:administration & dosage / Q000378:metabolism / Q000502:physiology; D008070:Lipopolysaccharides / Q000008:administration & dosage / Q000633:toxicity*; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D043783:Receptor, Bradykinin B1 / Q000008:administration & dosage / Q000096:biosynthesis* / Q000502:physiology*
C476306:Ac-Orn-(Oic2, alpha-MePhe5, D-betaNal7, Ile8)desArg9-bradykinin; D065169:Bradykinin B1 Receptor Antagonists; D016207:Cytokines; D018836:Inflammation Mediators; D008070:Lipopolysaccharides; D043783:Receptor, Bradykinin B1; D001920:Bradykinin