Long-term administration of PUFA is known to modulate immune functions and apoptotic pathways depending on the respective amount of n-6 and
n-3 fatty acids (FA). Data on short-term effects on apoptotic pathways are rare. Apoptosis of splenic lymphocytes is the hallmark of detrimental
sepsis. Therefore, we aimed to compare the immediate effects of parenterally administered n-6-enriched soyabean oil (SO)- and n-3-enriched
fish oil (FO)-based
lipid emulsions after
laparotomy (LAP;
sham procedure) and after induction of acute,
severe sepsis by caecal
ligation and incision. After 390 min of observation time, plasma was analysed for IL-1β,
IL-6 and
NEFA. Apoptosis in splenic lymphocytes was quantified by
Annexin-V expression. After LAP, infusion of both FO and SO did not change
cytokine concentrations.
Sepsis increased both
cytokines. FO but not SO further augmented the rise. After LAP, SO increased
NEFA, and both
lipid emulsions reduced free
arachidonic acid (AA).
Sepsis resulted in a dramatic decrease in
NEFA and AA. The drop in
NEFA and AA was prevented by both SO and FO. In addition, FO resulted in an increased concentration of n-3 FA under both conditions. Infusion of both
lipid emulsions induced apoptosis in splenic lymphocytes after LAP.
Sepsis-induced apoptosis was not further enhanced by FO or SO. The present study shows that short-term administration of FO as opposed to SO caused pro-inflammatory effects during
sepsis. Moreover, short-term administration of both SO and FO suffices to induce apoptosis in splenic lymphocytes. Finally, SO and FO do not further enhance
sepsis-induced splenic apoptosis.