Exogenous sphingomyelinase causes impaired intestinal epithelial barrier function

Figure 4 A: Lipid analysis by tandem mass spectrometry revealed a rapid accumulation of ceramide in preparations of DIGs after incubation with 0. 25 U/mL SMase for 10 or 30 min whereas the increase of ceramide in the cell lysate was only small in comparison (^bP < 0.01); B: The content of sphingomyelin in DIGs decreased at the same time with a relative reduction comparable to the generation of ceramide (^dP < 0.01); C: Cholesterol also decreased in DIGs whereas the concentration in the cell lysate remained constant (^eP < 0.05 and ^fP < 0.01).