Analysis and subcellular localization of lipid in alcoholic liver disease.
The nature and subcellular distribution of lipids in alcoholic liver disease have been little studied. Micro-methods for lipid analysis were applied to needle biopsy homogenates and their subcellular fractions. Alcoholic fatty liver was accompanied by a major increase (up to 50 fold) in triglyceride and a smaller (2-3 fold) increase in cholesteryl ester: there was no significant change in the free cholesterol, free fatty acid or phospholipid content. Homogenates were fractionated into macro- and micro-droplets and membrane fractions by differential centrifugation. The subcellular location of the membrane lipids were determined by sucrose density gradient centrifugation in a vertical pocket reorientating rotor. In fatty liver, although there was a 2-3 fold increase in macro-droplet and micro-droplet (tentatively identified as VLDL) lipid, the major increase was in the membrane-bound triglyceride (8-10 fold). Sucrose density gradient centrifugation demonstrated that these membranes had an equilibrium density of 1.12 g/ml, clearly separated from droplet lipid, density less than 1.04 g/ml. The membrane fraction was tentatively identified as Golgi in origin and it is suggested that alcoholic fatty liver in man is due to impaired Golgi secretion of triglyceride-rich lipid complexes.
D001707:Biopsy, Needle; D002458:Cell Fractionation; D005234:Fatty Liver / Q000473:pathology; D006801:Humans; D008055:Lipids / Q000032:analysis*; D008099:Liver / Q000648:ultrastructure*; D008108:Liver Diseases, Alcoholic / Q000473:pathology*; D008832:Microchemistry; D008855:Microscopy, Electron, Scanning; D013347:Subcellular Fractions / Q000032:analysis*; D014018:Tissue Distribution; D014280:Triglycerides / Q000032:analysis
D008055:Lipids; D014280:Triglycerides