Fig. 1. Disruption of ceramide-sphingosine balance in cystic fibrosis. In healthy cells and in individuals, a low ceramide and high sphingosine level maintains a balance. In contrast, abnormally high ceramide and low sphingosine levels activate several signaling pathways, such as integrin accumulation, CD95 activation, and proinflammatory and anti-inflammatory cytokines, in the airways of cystic fibrosis patients or cells.