Down‐regulated surfactant protein B in obese asthmatics

摘要

Abstract Background Obesity is a common comorbid condition in adult asthmatics and known as a feature of asthma severity. However, the molecular mechanism under obesity‐induced inflammation has not yet been fully understood. Objective Considering the essential role of hydrophobic surfactant protein B (SP‐B) in lung function, SP‐B was targeted to examine its involvement in the development of obesity‐induced airway inflammation in asthmatics. Methods The aim was to examine an alteration in circulating SP‐B according to obesity in adult asthmatics, 129 asthmatics were enrolled and classified into 3?groups (obese, overweight and normal‐weight groups) according to body mass index (BMI). Circulating SP‐B levels were determined by enzyme‐linked immunosorbent assay. Four single nucleotide polymorphisms of SFTPB gene were genotyped. Serum ceramide levels were measured by liquid chromatography‐tandem mass spectrometry. Results Significantly lower serum SP‐B levels were noted in the obese group than in the overweight or normal‐weight group (p?=?.002). The serum SP‐B level was significantly correlated with serum levels of C18:0 ceramide and transforming growth factor beta?1 as well as BMI (r?=??0.200; r?=??0.215; r?=??0.332, p?G to the obese and overweight groups was noted. Conclusion Obesity altered ceramide metabolism leading to pulmonary surfactant dysfunction and impaired?resolution of airway inflammation, finally contributing to the phenotypes of obese asthmatics.