Characterization of ceramide generation kinetics in a lung injury model induced by lipopolysaccharide

Background: Ceramide participate in various pathophysiologic events in ARDS and can be formed through several pathways. The specific pathways leading to ceramide formation in ARDS are not yet elucidated. Objectives: To characterize the kinetics of the enzymes regulating ceramide formation in both de novo [serine palmitoyl transferase (SPT) and dihydroceramide synthase (DS)] and sphingomyelinase [acid (ASM) and neutral sphingomyelinase (NSM)] pathways in a LPS-induced injury model. Methods: The ethics committee on animal use of our University approved the study (code: IBCCF 140). 36 male C57BL/6 mice, 6-8 wks (23-25 g) were intratracheally (i.t.) instilled with 2 mg/kg LPS/50 µL saline and euthanized at 0, 2, 4, 6, 12 and 24 hours after exposure. The lungs were removed and homogenized. Dynamic expression of ASM, NSM, SPT and DS were determined in the homogenate at these different times by western blotting. Results: The figure displays the kinetics of SPT, DS, ASM and NSM enzymes by Western blotting at 0,2,4,6,12 and 24 hours after LPS challenge . All the enzymes expressions had increased compared to control group until 4 hours after LPS challenge. ![Figure][1] Conclusions: LPS can activate both ceramide-generating pathways in a short time after LPS challenge. [1]: pending:yes