Hyperosmolarity-induced lipid droplet formation depends on ceramide production by neutral sphingomyelinase 2.

ABSTRACT: Hyperosmolarity (HO) imposes a remarkable stress on membranes, especially in tissues in direct contact with the external environment. Our efforts were focused on revealing stress-induced lipid changes that precede the inflammatory cytokine response in human corneal epithelial cells exposed to increasing osmolarity. We used a lipidomic analysis that detected significant and systematic changes in the lipid profile, highly correlated with sodium concentrations in the medium. Ceramides and triglycerides (TGs) were the most-responsive lipid classes, with gradual increases of up to 2- and 3-fold, respectively, when compared with control. The source of ceramide proved to be sphingomyelin hydrolysis, and neutral sphingomyelinase 2 (NSM2) activity showed a 2-fold increase 1 h after HO stress, where

SUBMITTER: Robciuc A 

PROVIDER: S-EPMC3465998 | biostudies-literature | 2012 Nov

REPOSITORIES: biostudies-literature