title: [Effects of dexamethasone on 15-lipoxygenase expression in lungs of asthmatic rats].
abstract: OBJECTIVE
  15-lipoxygenase (15-LO) is a prooxidant enzyme which is expressed in asthmatic lungs leading to formation of pro- and anti-inflammatory mediators. Gene expression profiling studies show the association between 15-LO and allergic asthma. This study was designed to observe the expression of 15-LO in lungs of asthmatic rats and examine the effects of dexamethasone on 15-lipoxygenase expression.
  
  
  METHODS
  Twenty-seven male Sprague-Dawley (SD) rats were randomly divided into three groups: control, asthma and dexamethasone (DXM) intervention. An asthma model was prepared by sensitization and challenging with ovalbumin. The production of 15-LO in lung tissue homogenates was measured using ELISA.The expression of 15-LO mRNA in lungs was determined by reverse transcription-polymerase chain reaction (RT-PCR).
  
  
  RESULTS
  The levels of 15-LO mRNA and protein in the asthma group (0.51 ± 0.14 and 2080 ± 73 μg/mL, respectively) were lower than those in the control group (0.76 ± 0.15 and 2472 ± 106 μg/mL, respectively; P<0.01). DXM intervention increased significantly the levels of 15-LO mRNA and protein (1.02 ± 0.34 and 2562 ± 218 μg/mL) compared with the asthma group (P<0.01).
  
  
  CONCLUSIONS
  The production of 15-LO in lung tissues is reduced in asthmatic rats. DXM can increase the expression of 15-LO in lung tissues and thus might provide anti-inflammatory effects in asthmatic rats.
authors.affiliation: Department of Respiratory Diseases, Yuying Children's Hospital of Wenzhou Medical College, Wenzhou, Zhejiang 325027, China.
authors.forename: Li-Sha
authors.initials: LS
authors.lastname: Ge
authors.forename: Chang-Chong
authors.initials: CC
authors.lastname: Li
authors.forename: Wei-Xi
authors.initials: WX
authors.lastname: Zhang
authors.forename: Ya-Feng
authors.initials: YF
authors.lastname: Liang
authors.forename: He
authors.initials: H
authors.lastname: Zhang
mesh_terms: D000818:Animals; D000893:Anti-Inflammatory Agents / Q000494:pharmacology*; D001093:Arachidonate 15-Lipoxygenase / Q000032:analysis / Q000235:genetics*; D001249:Asthma / Q000188:drug therapy / Q000201:enzymology*; D003907:Dexamethasone / Q000494:pharmacology*; D008168:Lung / Q000201:enzymology* / Q000473:pathology; D008297:Male; D011897:Random Allocation; D051381:Rats; D017207:Rats, Sprague-Dawley
chemical_list: D000893:Anti-Inflammatory Agents; D003907:Dexamethasone; D001093:Arachidonate 15-Lipoxygenase