Leptin and urinary leukotriene E4 and 9α,11ß-prostaglandin F2 release after exercise challenge.

ABSTRACT

BACKGROUND: Leptin-related effects on inflammation and bronchial hyperresponsiveness (BHR) in the human airway have not been demonstrated. OBJECTIVES: To investigate the relationship between the levels of serum leptin and BHR and urinary leukotriene E4 (LTE4) and 9α,11ß-prostaglandin F2 (9α,11ß-PGF(2)) release after exercise challenge in asthmatic children. METHODS: Eighty-six prepubertal children between 6 and 10 years old were enrolled and divided into 4 groups 19 obese asthmatic children, 25 normal-weight asthmatic children, 21 obese nonasthmatic children, and 21 healthy controls. We measured serum leptin levels and urinary LTE4 and 9α,11ß-PGF2 levels in children before and 30 minutes after the exercise challenge. RESULTS: Serum leptin levels were significantly higher in obese asthmatic children compared with normal-weight asthmatic children. Significant increases in urinary levels of LTE4 and 9α,11ß-PGF2 were observed in obese asthmatic children after the exercise challenge. Although smaller than in obese asthmatic children, significant increases in the urinary levels of LTE4 and 9α,11ß-PGF2 were also observed in the normal-weight. Asthmatic children Logarithmic serum leptin values were significantly associated with the logarithmic maximum percentage change in forced expiratory volume in 1 second, the logarithmic urinary LTE4 change, and the logarithmic urinary 9α,11ß-PGF2 change from baseline to after exercise in both obese and normal-weight asthmatic children. CONCLUSION: The serum levels of leptin were significantly associated with BHR and urinary LTE4 and 9α,11ß-PGF2 release induced by exercise challenge in asthmatic children.