PUFAs and Their Newly Discovered Roles

Dietary linoleic acid (18 2, u-6) A precursor of AA, an essential component of cell membranes, is the substrate for the 2-series eicosanoida, which ate the most biologically potent eicosanoids. 

Arachidonic acid (20 4, i -6) Small amounts of this are consumed in the diet in the form of meat It is a precursor for the 2-series eicosanoids. 

Linolenic acid (18 3, o -3) A precursor (rf EPA and DHA. DHAisan essential conqxment of neural membranes. EPA is the substrate for the series-3 eicosanoids, which are relatively less active compared to those from AA. 

Eicosiq entaaioic acid (20 5, (, -3) The precursor for die series-3 eicosanoids. It replaces AA in membrane phospholipids. EPA is selectively incorporated into the eicosanoid precursor pool of phospholipids. Like AA, it is released from membrane phospholipids. It competes wtdi AA fiir oxygenases. 

On the other hand, the increased GPx activity (possibly via protein synthesis) might be associated with an oxidative stress induced by DHA (22 6, i)-3) and/or AA (20 4,0-6) released fixnn a platelet endogenous pool in the course of the DHA (22 6, o-3) enrichment (97). Similar to the findings in our laboratory, DHA (22 6, u -3) estoified to tri ycerides is rapidly redistributed within blood lipxqnioteins. The DHA (22 6, w-6) bound and circulate with the albumin fraction not only inhibit platelet aggregation but also influences its uptake into phospholipid species by target tissues (98). DHA therefore seems to impact platelet fatty acid metabolism through unique and novel mechanisms. 

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