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.
GE Li-Sha,LI Chang-Chong,ZHANG Wei-Xi et al. Effects of dexamethasone on 15-lipoxygenase expression in lungs of asthmatic rats[J]. CJCP, 2011, 13(3): 227-230.
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