Visualization of sphingolipids and phospholipids in the fundic gland mucosa of human stomach using imaging mass spectrometry

摘要

AIM:To analyze the lipid distribution in gastric mucosae.METHODS:Imaging mass spectrometry(MS)is a useful tool to survey the distribution of biomolecules in surgical specimens.Here we used the imaging MS apparatus named i MScope to identify the dominant molecules present in the human gastric mucosa near the fundic glands.Five gastric specimens were subjected to iM Scope analysis.These specimens were also analyzed by immunohistochemistry using MUC5 AC,H(+)-K(+)-ATPaseβ Claudin18 antibodies.RESULTS:Three major molecules with m/z 725.5,780.5,and 782.5 detected in the gastric mucosa were identified as sphingomyelin(SM)(d18:1/16:0),phosphatidylcholine(PC)(16:0/18:2),and PC(16:0/18:1),respectively,through MS/MS analyses.Using immunohistological staining,SM(d18:1/16:0)signals were mainly colocalized with the foveolar epithelium marker MUC5 AC.In contrast,PC(16:0/18:2)signals were observed in the region testing positive for the fundic gland marker H(+)-K(+)-ATPaseβ.PC(16:0/18:1)signals were uniformly distributed throughout the mucosa.CONCLUSION:Our basic data will contribute to the studies of lipid species in physical and pathological conditions of the human stomach.