title: Corticosteroid administration reduces the concentration of hyaluronan in bronchoalveolar lavage in a murine model of eosinophilic airway inflammation.
abstract: 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.
  
  
  METHODS
  Untreated-mice or mice treated with 1 μg/g/day betamethasone (Bm) or 0.25 μg/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 < 0.01) 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.
  
  
  CONCLUSIONS
  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.
authors: Department of Immunology, Faculty of Pharmacy and Biochemistry, IDEHU, UBA-CONICET, University of Buenos Aires, Junin 956 4th floor, 1113 Buenos Aires, Argentina. glenda.uba@gmail.com
authors: Glenda
authors: G
authors: Ernst
authors: Silvina
authors: S
authors: Lompardía
authors: Rosalía
authors: R
authors: Cordo Russo
authors: Virginia
authors: V
authors: Gentilini
authors: Stella
authors: S
authors: Venturiello
authors: Fernando
authors: F
authors: Galíndez
authors: Pedro
authors: P
authors: Grynblat
authors: Silvia E
authors: SE
authors: Hajos
mesh_terms: D000485:Allergens; D000818:Animals; D000893:Anti-Inflammatory Agents / Q000494:pharmacology; D039741:Antigens, Dermatophagoides; D001623:Betamethasone / Q000494:pharmacology*; D001992:Bronchoalveolar Lavage Fluid / Q000737:chemistry / Q000276:immunology; D019819:Budesonide / Q000494:pharmacology*; D004195:Disease Models, Animal; D004802:Eosinophilia / Q000276:immunology*; D048049:Extracellular Signal-Regulated MAP Kinases / Q000276:immunology; D005260:Female; D005938:Glucocorticoids / Q000494:pharmacology*; D014453:Glucuronosyltransferase / Q000235:genetics; D000076002:Hyaluronan Synthases; D006820:Hyaluronic Acid / Q000276:immunology*; D051379:Mice; D008807:Mice, Inbred BALB C; D011014:Pneumonia / Q000276:immunology*; D051057:Proto-Oncogene Proteins c-akt / Q000276:immunology
chemical_list: D000485:Allergens; D000893:Anti-Inflammatory Agents; D039741:Antigens, Dermatophagoides; D005938:Glucocorticoids; D019819:Budesonide; D006820:Hyaluronic Acid; D001623:Betamethasone; D014453:Glucuronosyltransferase; D000076002:Hyaluronan Synthases; D051057:Proto-Oncogene Proteins c-akt; D048049:Extracellular Signal-Regulated MAP Kinases