Expressions of matrix metalloproteinase-16, autophagy-related gene 5 and autophagy-related gene 7 in children with bronchial asthma and their correlations with pulmonary function

  Objective  To investigate the correlations of expression levels of matrix metalloproteinase-16 (MMP-16), autophagy-related gene 5 ( ATG5 ) and autophagy-related gene 7( ATG7 ) in peripheral blood mononuclear cells with pulmonary function in children with bronchial asthma.

  Methods  Eighty children with asthma were selected as observation group, and eighty healthy children were selected as control group. Blood samples were collected from the observation group and control group, the forced expiratory volume in the first second as a percentage of the predicted value (FEV₁%), forced vital capacity (FVC) and maximum peak expiratory flow as a percentage of the predicted value (PEF%) were detected, and ratio of forced expiratory volume in the first second to forced vital capacity (FEV₁/FVC) was calculated. Real-time fluorescent quantitative PCR (qRT-PCR) method was used to detect the levels of MMP-16 mRNA, ATG5 mRNA and ATG7 mRNA in peripheral blood mononuclear cells; Pearson method was used to analyze the correlations of MMP-16 mRNA, ATG5 mRNA and ATG7 mRNA with pulmonary function indexes in children with acute asthma.

  Results  The levels of MMP-16 mRNA, ATG5 mRNA and ATG7 mRNA were significantly and successively increased in the control group and the children with clinical remission and acute attack in the observation group (P<0.05); FEV₁%, FEV₁/FVC and PEF% were significantly and successively reduced in the control group and the children with clinical remission and acute attack in the observation group (P<0.05). There were significant positive correlations between MMP-16 mRNA and ATG5 mRNA, MMP-16 mRNA and ATG7 mRNA, and ATG5 mRNA and ATG7 mRNA in peripheral blood mononuclear cells of children with acute asthma (r=0.536, 0.542, 0.534, P<0.05), and MMP-16 mRNA, ATG5 mRNA, ATG7 mRNA were negatively correlated with FEV₁%, FEV₁/FVC and PEF% (P<0.05). Compared with the mild group, the levels of MMP-16 mRNA, ATG5 mRNA and ATG7 mRNA in peripheral blood mononuclear cells of the moderate to severe group were significantly higher, while the FEV₁%, FEV₁/FVC and PEF% were significantly lower (P<0.05).

  Conclusion  The levels of MMP-16 mRNA, ATG5 mRNA and ATG7 mRNA in peripheral blood mononuclear cells of children with asthma are higher, and these indexes are closely related to pulmonary function.