Influence of leptin on Th1/Th2 balance in obese children with asthma / 中国免疫学杂志

ABSTRACT

Objective:To investigate the levels of serum leptin and their effect on Th 1/Th2 balance and the association between serum leptin levels and clinical manifestations in obese children with asthma.Methods: All 56 children with physician-diagnosed moderate-to-severe persistent asthma and 56 healthy controls were included.The children with asthma and without asthma were divided into two groups,obese (n=28) and non-obese (n=28) by body mass index,respectively.Asthma severity was assessed by the asthma symptom score.Peripheral blood samples were collected to determine the levels of leptin , IFN-gamma and IL-4.The results were correlated with the parameters studied.Results:Serum leptin levels were significantly higher in the obese asthma group than in the non -obese asthma group ,as well as being significantly higher in the children with asthma than in the controls ( P<0.01 ) , whereas IFN-gamma levels were significantly higher and IL-4 levels were significantly lower in the obese asthma group than in the non-obese asthma group( P<0.01 ).In addition, the obese asthma group showed higher asthma symptom scores and significantly lower FEV 1 (% of predicted) than did the non-obese asthma group(P<0.01).There was a significantly positive correlation between leptin ,IFN-gamma and IL-4 levels only in the obese asthma group ( P<0.01 ).Conclusion:Leptin is involved in the pathogenesis of asthma in obese and non-obese children ,and its effect is more pronounced in the former.In the presence of high leptin levels , only obese children with asthma exhibited Th1 polarization,with higher IFN-gamma levels and greater asthma severity.