Model membrane and cellular detergent extraction studies show (n-3) PUFA predominately incorporate into nonrafts;
thus, we hypothesized (n-3)...
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Model membrane and cellular detergent extraction studies show (n-3) PUFA predominately incorporate into nonrafts;
thus, we hypothesized (n-3) PUFA could disrupt nonraft organization. The first objective of this study was to determine
whether (n-3) PUFA disrupted nonrafts of EL4 cells, an extension of our previous work in which we discovered an (n-3)
PUFA diminished raft clustering. EPA or DHA treatment of EL4 cells increased plasma membrane accumulation of the
nonraft probe 1,19-dilinoleyl-3,3,39,39-tetramethylindocarbocyanine perchlorate by ;50–70% relative to a BSA control.
Fo¨ rster resonance energy transfer imaging showed EPA and DHA also disrupted EL4 nanometer scale nonraft
organization by increasing the distance between nonraft molecules by ;25% compared with BSA. However, changes in
nonrafts were due to an increase in cell size; under conditions where EPA or DHA did not increase cell size, nonraft
organization was unaffected. We next translated findings on EL4 cells by testing if (n-3) PUFA administered to mice
disrupted nonrafts and rafts. Imaging of B cells isolated from mice fed low- or high-fat (HF) (n-3) PUFA diets showed no
change in nonraft organization compared with a control diet (CD). However, confocal microscopy revealed the HF (n-3)
PUFA diet disrupted lipid raft clustering and size by ;40% relative to CD. Taken together, our data from 2 different model
systems suggest (n-3) PUFA have limited effects on nonrafts. The ex vivo data, which confirm previous studies with EL4
cells, provide evidence that (n-3) PUFA consumed through the diet disrupt B cell lipid raft clustering.
