Studies on the correlation between antioxidants and PUFA-oxidation in vivo, possible relations to LDL-oxidation and platelet activation

Dietary fat is believed to play a role in development of atherosclerosis and cancer. The composition and distribution of the lipoproteins transporting the dietary fat to the tissues is a factor in determining the potential atherogenicity of the diet. Much interest has been focused on the protection against atherosclerosis of antioxidants present in the low-density lipoproteins (LDL). However, high-density lipoprotein (HDL) and very low-density lipoprotein (VLDL) may also play important roles in protection against coronary artery disease.
Dietary supplements of antioxidants are popular among the population, as well as supplements of fish oil containing high amounts of polyunsaturated fatty acids (PUFAs). The PUFAs are, in addition to their beneficial effects of total plasma lipid levels, vulnerable to oxidation when transported in the lipoproteins, and increase the demand for antioxidative protection.
The importance of classical antioxidants as vitamin E and C is well recognized, but recent studies have questioned whether the recommended intake is sufficient to match present dietary intakes of PUFA. Other redox-active components, such as various carotenoids and coenzyme Q10 must be included in such a validation.
The issues to be studied include:
Basic examinations of the co-operative effect of antioxidants present in LDL and HDL
Formation of oxidation products which can be used as biochemical markers, such as lipid hydroperoxides, the redox status of coenzyme Q or formation of so-called "core aldehydes".
Supplemented coenzyme Q and vitamin E are absorbed but distributed differently within lipoprotein classes. Vitamin E follows PUFA thus providing optimal protection against oxidation.