Comparative toxicity of oleic acid and linoleic acid on Jurkat cells

Background: Lipid emulsions for parenteral nutrition commercially available are mainly composed of long-chain triacylglycerol containing a high proportion of omega-6 polyunsaturated fatty acids or omega-9 monounsaturated fatty acids. The immunological impact of such therapy is particularly important because parenteral and enteral diets are often administered to critical ill patients. The comparative toxicity of oleic acid and linoleic acid on Jurkat cells, a human T lymphocyte cell line, and the type of cell death induced by these fatty acids were determined. Methods: Cell death was investigated by cytometry: decrease in cell volume, increase of granularity, DNA fragmentation, phosphatidylserine externalization, mitochondrial depolarization, lipid accumulation; by fluorescence microscopy: chromatin condensation and acridine orange/ethidium bromide assay; and by RTPCR: mRNA expression of apoptotic genes. Results: Evidence is presented herein that oleic acid is much less toxic to Jurkat cells than linoleic acid. Both fatty acids promote apoptosis and necrosis of these cells. The mechanism of cell death induced by these fatty acids seem to involve with mitochondrial depolarization, lipid accumulation and the levels of C-MYC and P53 mRNA expression. Conclusion: Therefore, oleic acid may offer an immunological less harmful alternative to linoleic acid for parenteral and enteral diets preparation. (C) 2003 Elsevier Ltd. All rights reserved.