Loss of natural killer cell activity after murine tumor transplantation appears as a consequence of dietary lipid administration

It is generally assumed that unsaturated fatty acids are important biologic al mediators that may be applied in the treatment of patients suffering fro m autoimmune disorders, in the modulation of tumorigenic processes or in th e induction or inhibition of apoptosis. In this study, mice divided into th ree groups were fed dietary lipids; olive oil (20% w/w), fish oil (20% w/w) or hydrogenated coconut oil (20% w/w) for four weeks. Then, survival perce ntage, natural killer (NK) cell activity and lipid peroxidation were measur ed after murine lymphoma (LSTRA) transplantation. Survival percentage showe d a reduced resistance to LSTRA tumor in mice fed fish oil diet and general y loss of NK cell activity was observed after lymphoma transplantation. Lip id peroxidation from mice fed dietary lipids was measured in the presence o f both phospholipase and cyclooxygenase inhibitors. In general, the data co ntained in this paper point to a detrimental effect caused by dietary lipid s in mice transplanted with a lymphoma.