Double lipoxygenation of polyunsaturated fatty acids of nutritional interest.

Double lipoxygenation of polyunsaturated fatty acids having at least three methylene-interrupted double bonds can be made by two lipoxygenases, e.g. 5- and 12-LOX, or 15-LOX only, followed by reduction of the hydroperoxide products through the glutathione peroxidase action.

Biological relevance of double lipoxygenase products of polyunsaturated fatty acids, especially within blood vessels and brain.

The double lipoxygenation of polyunsaturated fatty acids (PUFA) is possible with PUFA having at least three methylene-interrupted double bonds. Several PUFA of the omega-3/n-3 and -6 families may be converted through this route, and the products show interesting inhibitory effects on blood platelet function and cyclooxygenase activities. This review focuses on two main omega-3 PUFA of nutritional interest, namely docosahexaenoic acid (DHA/22:6n-3) and alpha linolenic acid (ALA/18:3n-3).

Oxygenation of polyunsaturated fatty acids and oxidative stress within blood platelets.

The oxygenation metabolism of arachidonic acid (ArA) has been early described in blood platelets, in particular with its conversion into the potent labile thromboxane A that induces platelet aggregation and vascular smooth muscle cells contraction. In addition, the primary prostaglandins D and E have been mainly reported as inhibitors of platelet function. The platelet 12-lipoxygenase (12-LOX) product, i.

Moderate intake of docosahexaenoic acid raises plasma and platelet vitamin E levels in cystic fibrosis patients.

Patients with cystic fibrosis have increased oxidative stress and impaired antioxidant systems. Moderate intake of docosahexaenoic acid (DHA) may favor the lowering of oxidative stress. In this randomized, double-blind, cross-over study, DHA or placebo capsules, were given daily to 10 patients, 5mg/kg for 2 weeks then 10mg/kg DHA for the next 2 weeks (or placebo).

In vitro and in vivo bimodal effects of docosahexaenoic acid supplements on redox status and platelet function.

Docosahexaenoic acid (DHA) is a prominent nutrient of marine lipids. Together with eicosapentaenoic acid, it is recognized as a protective molecule against atherosclerosis and thrombosis through the regulation of blood cell functions, especially platelets. Its high unsaturation index may however make it prone to peroxidation, which is usually considered as deleterious.