This study investigated the effect of dietary
fish oil on systemic
inflammation and hepatic injury in mice with polymicrobial
sepsis. Male ICR mice were assigned to a control group (C,
n=30) and a
fish oil group (FO,
n=30). Mice in the C group were fed a semi-purified diet with 10%
soybean oil, and those in the FO group were fed a
fish oil diet (2.5% fish oil+7.5%
soybean oil; w/w). Three weeks later,
sepsis was induced by cecal
ligation and
puncture (CLP), and mice were sacrificed at 0, 6 and 24 h after CLP, respectively. Results showed that compared with C group, the FO group had lower plasma levels of
tumor necrosis factor (TNF)-α,
interleukin (IL)-6,
IL-10, and
nitrite at 6 and 24 h after CLP. Also, peritoneal lavage fluid concentrations of TNF-α and
prostaglandin (PG) E2 were significantly lower at 24 h in the FO than in the C group. The FO group had lower
myeloperoxidase activities at 6 h after CLP in various organs. Plasma
aminotransferase and
alanine aminotransferase activities revealed significantly decreased in the FO group. The
DNA-binding activity of
peroxisome proliferators-activated receptor gamma (PPARγ) and
mRNA expression of I kappaB alpha (IκBα) were up-regulated while nuclear factor (NF)-κB p65
DNA-binding activity,
inducible nitric oxide synthase protein expression and the concentration of
nitrotyrosine were significantly decreased in the FO group in liver after CLP. These results indicate that dietary
fish oil administration may attenuate systemic
inflammation and up-regulate hepatic PPARγ
DNA-binding activity, which may consequently have ameliorated liver injury in these septic mice.