Abstract: Objective To investigate the potential effect of adiponectin/ AMP-activated protein (AMPK ) signaling pathway on the airway inflammation and airway hyperreactivity in obesity-related asthma. Methods Forty male C57BL/6 mice were randomly divided into four groups, which were designed as control group(A), asthma group(B) ,obese group(C) and obese asthma group(D). The mice in group A were fed with normal diet , sensitized and challenged with saline. The mice in group B were sensitized and challenged with ovalbumin(OVA) and fed with normal diet. The mice in group C and D were fed with high fat diet, the mice in group D were sensitized and challenged with OVA and the mice in group C used saline instead. After 12 weeks, airway resistances(RL) were determined and the histopathologies of lung tissues were observed .Real-time PCR was used to detect the expressions of adiponectin mRNA、AdipoR1 mRNA and AMPKα mRNA and Westem blotting was used to detect the expressions of adiponectin、phosphor-AMPKα(pAMPKα) and AMPKα proteins．Results The mean weight of high fat food feeding mice was 20% higher than mice feeding with normal diet and achieved the standard of obesity at the 12 weeks after feeding, the difference was significant(P＜0.01). Compared to group A, the expression level of adiponectin mRNA,AdipoR1 mRNA as well as the adiponectin protein and pAMPKα protein in lung were significantly decreased in the other three groups with group D most obviously(P<0.05).Conclusions The airway responsiveness was higher in obesity-related asthma, which may partly due to the down-regulation of Adipo/AMPK signaling pathway.

Key words: asthma, obesity, adiponectin, AMPK