Corticosteroid administration reduces the concentration of hyaluronan in bronchoalveolar lavage in a murine model of eosinophilic airway inflammation

ERNST, G; LOMPARDÍA S; CORDO RUSSO R; GENTILINI V; VENTURIELLO S; GALINDEZ F; GRYNBLAT P; HAJOS S E

INFLAMMATION RESEARCH

BIRKHAUSER VERLAG AG

Lugar: BASEL; Año: 2012

1023-3830

Objective To analyze the effect of corticosteroid administration on the concentration of hyaluronan (HA) in bronchoalveolar lavage (BAL) in a murine model of eosinophilic airway inflammation and to study the mechanisms involved. Materials and methods Untreated-mice or mice treated with 1 lg/g/day betamethasone (Bm) or 0.25 lg/g/day-1 budesonide (Bd) were sensitized and challenged with Dermatophagoides pteronyssinus (Dp) or saline (control group). The concentration of HA in BAL was determined by ELISA. In vitro migration assays were performed using a Boyden chamber and the expression of HA synthases (HAS) was analyzed by RT-PCR. Results We found a significant increase (P�.01) in the levels of HA in BAL from Dp-treated mice that was prevented by Bm or Bd. Corticosteroids also inhibited the increase in HAS expression, and the phosphorylation of Akt and ERK in the lungs of challenged mice. Finally, we found that low molecular weight HA induces the chemotaxis of BAL cells in vitro through a mechanism mediated by CD44. Conclusion We conclude that corticosteroids prevent the increase in HA in BAL from Dp-challenged mice. This effect is associated with reduced expression of HAS and reduced phosphorylation of Akt and ERK in the lungs of challenged mice.