Secretory phospholipases A 2 (sPLA 2 ) have functions relevant to asthmatic inflammation, including eicosanoid synthesis and effects on dendritic cells and T cells. The aim of this study was to measure sPLA 2 activity in patients with stable and acute asthma and to assess potential associations with body mass index (BMI), and plasma cholesterol and vitamin C concentrations. Methods: Plasma sPLA 2 activity and concentrations of cholesterol and vitamin C were measured in 23 control subjects and

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... subjects with stable asthma (42 mild to moderate, 19 severe). In addition, sPLA 2 activity was measured in 36 patients experiencing acute asthma and in 22 of these patients after recovery from the acute attack. Results: sPLA 2 activity was not significantly greater in severe (499.9 U; 95% confidence interval (CI) 439.4 to 560.4) compared with mild to moderate asthmatic subjects (464.8; 95% CI 425.3 to 504.3) or control subjects (445.7; 95% CI 392.1 to 499.4), although it was higher in patients with acute asthma (581.6; 95% CI 541.2 to 622.0; p,0.001). Male gender, high plasma cholesterol, increased BMI and atopy were associated with increased sPLA 2 activity, while plasma vitamin C was inversely correlated with sPLA 2 activity in patients with stable asthma and in control subjects. There were significant interactions between gender and plasma cholesterol and between gender and vitamin C in relation to sPLA 2 activity. Conclusions: Plasma sPLA 2 may provide a biological link between asthma, inflammation, increased BMI, lipid metabolism and antioxidants. Interactions among these factors may be pertinent to the pathophysiology and increasing prevalence of both asthma and obesity. METHODS Subjects Patients with stable asthma were recruited from the databases of the Lung Institute of Western