Lipid Composition of the Plasma Membrane Isolated from Hyperplastic Nodules of Rat Liver1

Abstract

Hyperplastic nodules and hepatomas were induced in livers of rats fed a diet containing 0.05% N-2-fluorenylacetamide (2-FAA). The lipid contents, and phospholipid and fatty acid compositions were analyzed in plasma membranes (PM's) isolated from these tissues and normal rat liver, and the following trends were observed. The molar ratio of cholesterol to phospholipid-phosphorus (phospholipid-P) increased in the order: hepatoma less than normal liver less than hyperplastic nodules. The molar percentage of plasmalogen to phospholipid-P decreased in the order: hepatoma = hyperplastic nodules greater than normal liver. The percentages of choline phosphoglycerides (sum of phosphatidylcholine and lysophosphatidylcholine) and ethanolamine phosphoglycerides (sum of phosphatidylethanolamine and lysophosphatidylethanolamine) both decreased in the order: hepatoma greater than hyperplastic nodules greater than normal liver. On the other hand, the percentages of sphingomyelin and phosphatidylserine both increased in the order: hepatoma less than hyperplastic nodules less than normal liver. As regards fatty acid composition, the percentages of both 18:1 and 18:2 decreased in the order: hepatoma greater than hyperplastic nodules greater than normal liver. Those of 18:0 and 20:4 increased in the order: hepatoma less than hyperplastic nodules less than normal liver. These results suggested that the lipid bilayer in PM of hyperplastic nodules has characteristics roughly intermediate between those of hepatoma and liver PM's, although the molar ratio of cholesterol to phospholipid-P in hyperplastic nodules PM was not intermediate.

Metabolism and pharmacokinetics of a novel polyphenol fatty acid ester phloridzin docosahexaenoate in Balb/c female mice

“…Since the accumulation of PZ, DHA, and PZ-DHA are similar in malignant and non-malignant cells, the selective cytotoxic action is unlikely due to altered drug uptake and/or efflux. However, it is possible that PZ-DHA binds to the inner leaflet of the phospholipid bi-layer of the cell membrane and does not move into the cell interior of non-malignant cells because of differences in lipid and fatty acid composition of the phospholipid bi-layer of malignant and non-malignant cell membranes [34][35][36] . Interestingly, PZ-DHA uptake was not statistically different between all tested cell lines, suggesting that PZ-DHA uptake is not cell type-dependent.…”