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Medical AI Inquiry: You was designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.  Labels: BACKGROUND, METHODS, RESULTS. Meshes: Animals, Antioxidants, Arachidonic Acid, Carcinoma, Hepatocellular, Cell Death, Cell Survival, DNA, Neoplasm, L-Lactate Dehydrogenase, Lipid Peroxidation, Liver Neoplasms, Experimental, Oxidative Stress, Phosphatidylcholines, Rats, Tumor Cells, Cultured.
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Is dilinoleoylphosphatidylcholine the active antioxidant of polyenylphosphatidylcholine? Context: Polyenylphosphatidylcholine, a mixture of polyunsaturated phospholipids, prevents the fibrosis induced by alcohol in baboons and by CCl4 in rats and opposes the associated oxidative stress. To determine the responsible phosphatidylcholine species, a Morris hepatoma cell line (RH 7777) was incubated with 100 mumol/L arachidonate supplemented with 20 mumol/L dilinoleoylphosphatidylcholine or 20 mumol/L palmitoyllinoleoylphosphatidylcholine which comprise 42% and 24% of polyenylphosphatidylcholine, respectively or with equivalent amounts of polyenylphosphatidylcholine. Distearoylphosphatidylcholine, the saturated analog of dilinoleoylphosphatidylcholine, also was used for comparison. Two markers of lipid peroxidation (4-hydroxynonenal and F2-isoprostanes) were measured by GC/MS. Arachidonate caused 8- and 11-fold rises of cellular 4-hydroxynonenal and F2-isoprostanes, respectively; these increases were reduced more than 50% by polyenylphosphatidylcholine and dilinoleoylphosphatidylcholine. By contrast, palmitoyllinoleoylphosphatidylcholine and distearoylphosphatidylcholine had no significant effect. Lipid peroxidation was associated with a striking exacerbation of cell death, observed microscopically, and documented by a 2.5-fold decrease in cellular DNA and a 2- to 3-fold increase in lactic dehydrogenase leakage. Dilinoleoylphosphatidylcholine and polyenylphosphatidylcholine decreased the release of lactic dehydrogenase (47% and 67%, respectively); whereas, palmitoyllinoleoylphosphatidylcholine had no effect.
assistant
An in vitro system of oxidative stress revealed that polyenylphosphatidylcholine is a potent antioxidant and that dilinoleoylphosphatidylcholine is mainly responsible for this protective effect; whereas, its saturated counterpart distearoylphosphatidylcholine is inactive. Final Decision: yes