Serum sphingosine-1-phosphate levels and Sphingosine-1-Phosphate gene polymorphisms in acute respiratory distress syndrome: a multicenter prospective study

Background Sphingosine-1-phosphate (S1P) is a signaling phospholipid involved in pathophysiologic progression of acute respiratory distress syndrome (ARDS) through its roles in endothelial barrier function and immune modulation. We hypothesized that decreased serum S1P level is associated with the clinical outcomes of ARDS and polymorphisms in the S1P gene are associated with serum S1P levels. Methods This multicenter prospective study includes ARDS patients and healthy blood donors as controls. Serum S1P levels were quantified using enzyme-linked immunosorbent assays. Eight tag single nucleotide polymorphisms (SNPs) in the S1P gene were detected, and their associations with S1P levels were evaluated. Results A total of 121 ARDS patients and 100 healthy individuals were enrolled. Serum S1P levels were lower in ARDS patients than in controls (P