Mechanisms involved in Jurkat cell death induced by oleic and linoleic acids.

Background & Aims: Previous study from our laboratory showed the toxicity of oleic (OA) and linoleic acids (LA) on Jurkat and Raji cells and human lymphocytes in vitro. The mechanisms involved in the toxicity induced by OA and LA on Jurkat cells were determined in vitro.
Methods: Jurkat cells were treated in the presence of OA and LA (25, 50, 100 and 200muM). The parameters investigated were: triglycerides and cholesterol ester concentrations determined by enzymatic assay, activation of peroxisome proliferator activated receptor (PPAR) by electrophoretic mobility shift assay, caspase 3, 6 and 8 activities by spectrofluorometric assay, tumor necrosis factor-alpha (TNF-alpha) and interferon-gamma production by enzyme linked absorbent assay (ELISA), expression of pro- (Bax) and anti- (Bcl-2) apoptotic genes by real time polymerase chain reaction and expression of pleiotropic genes by macroarray technique
Results: Evidence is presented herein that the increase in triglycerides concentrations induced by OA is more pronounced than that caused by LA in Jurkat cells. Importantly, triglycerides accumulation may be a mechanism to protect lymphocytes against the toxicity induced by fatty acids. Both fatty acids raised PPAR activation, caspase 3 and 6 activities and TNF-alpha production. LA in toxic concentrations modulated the expression of genes related to cell cycle, apoptosis, proliferation, oxidative stress, and cytokine receptors.
Conclusion: The findings reported herein support the cell death induced by OA and LA involved triglycerides accumulation, PPAR activation, caspase 3 and 6 activities and TNF-alpha production.