Abstract:
OBJECTIVE To analyze the expression levels and significance of peripheral blood miR-33 a, miR-222-3 p and miR-492 in children with asthma induced by
Mycoplasma pneumonia(MP) infection.
METHODS Total of 345 children with MP infection admitted to Three Gorges Hospital Affiliated to Chongqing University were enrolled in this study. According to the presence or absence of asthma, the children were divided into the induction group and non-induction group. The expression levels of peripheral blood miR-33 a, miR-222-3 p and miR-492 were compared between the two groups. The expression levels of miR-33 a, miR-222-3 p miR-492 in children with different MP-IgM titer at different stages of asthmatic attack in the induction group were compared. The correlation between above indicators and the stage of asthmatic attack and MP-IgM titer were analyzed. Logistics regression analysis was performed to screen independent risk factors for MP-induced asthma.
RESULTS The expression level of peripheral blood miR-33 a in the induction group was significantly lower than that in the non-induction group, while expression levels of miR-222-3 p and miR-492 were significantly higher than those in the non-induction group(
P<0.05). Among children with asthma induced by MP infection, miR-33 a in children with high MP-IgM titer was lower than that with low and medium titer, while miR-222-3 p and miR-492 were significantly higher than those with low and medium titer. The differences in the levels of miR-33 a, miR-222-3 p and miR-492 between children with low and medium titer were significant(
P<0.05). The level of miR-33 a in asthma children during acute attack stage was significantly lower than that during remission stage, while levels of miR-222-3 p and miR-492 were significantly higher than those during remission stage(
P<0.05). It was found by correlation analysis that miR-33 a level was negatively correlated with MP-IgM titer and acute asthma attack, while levels of 222-3 p and miR-492 were positively correlated with them(
P<0.05). The allergic history, family history of rhinitis/asthma, nebulization treatment, miR-222-3 p and miR-492 were independent risk factors for MP-induced asthma, while high level of miR-33 a was a protective factor(
P<0.05).
CONCLUSION The miR-33 a is lowly expressed, while miR-222-3 p and miR-492 are highly expressed in children with asthma induced by MP infection. The three factors are related to MP-IgM titer and stages of asthma attack.