Effects of short-term dietary administration of marginal levels of vitamin B6 and fish oil on lipid composition and antioxidant defences in rat tissues

Previous reports have shown that vitamin B-6 deficiency leads to peroxidative stress in rat organs. In this paper, we evaluated the effects on lipid peroxidation of short-term (six weeks) dietary administration of marginal contents of vitamin B-6. A further risk factor of susceptibility to peroxidation was the presence of fish oil with higher contents of n-3 polyunsaturated fatty acid (LCPUFA). The contemporaneous vitamin B-6 deficiency and presence of fish oil caused a C18:2 increase, a C20:4 decrease, and replacement of some n-6 LCPUFA with n-3 LCPUFA, without changes in the unsaturation index. In liver,TBARS production did not show any differences between dietary conditions, whereas the activities of glutathione-dependent enzymes were stimulated. In heart, fish oil increased lipid peroxidation, especially in the vitamin B-6-deficient group. (C) 2001 Harcourt Publishers Ltd.