The function of selected C20 PUFA a

The function of selected C20 PUFA as precursors of eicosanoids
for the synthesis of leukotrienes and PG may also play
a role. This is in concordance with the effects of borage oil.
GLA may be elongated to DGLA, which is metabolized to
PG of the series 1 and to 15-hydroxyeicosatrienoic acid.
Products of these eicosanoids mediate anti-inflammatory and
antiproliferative effects(11). However, ALA cannot be metabolized
to anti-inflammatory eicosanoids in tissues lacking
desaturases(11). Thus, other mechanisms are likely operative.
Long-chain n-3 fatty acids decrease the generation of inflammatory
cytokines, the expression of adhesion molecules and
probably the generation of reactive oxygen species(22). The
influence of ALA in these pathways is unclear. A study with
murine macrophages has shown that ALA down-regulates
inflammatory inducible nitric oxide synthase, cyclooxygenase-
2 and TNF-a gene expression interfering with NF-kB