Studies on the interaction between polyunsaturated fatty acids and antioxidants, with special reference to dietary supplementation

This study is a PhD-project for MSc Mette Thorn with Klaus Bukhave and Gunhild Hølmer as supervisors
The level of polyunsaturated fatty acids (PUFA) in cellular membranes reflects the dietary composition of fatty acids, where high levels of PUFA are supposed to have favorable effects on our immune defense, in addition to prophylactic effects in a wide range of diseases i.e. cardiovascular diseases and inflammatory disorders, acute as well as chronic.
PUFA are, however sensitive to oxidation, which may lead to the formation a number of potentially noxious compounds like free radicals, peroxides, and carbonylic compounds. Formation of these agents represents serious problems for industrial processing and storage of food stuffs with high contents of PUFA, but may also be a risk factor in consumption of diet rich in PUFA or by increasing PUFA intake through dietary supplementation.
The danish population comsumps a relatively large amount of n-3 PUFA capsules as dietary supplementation, why it is important to clarify whether this intake is matched by the intake of dietary antioxidants to antagonize the potentially noxious effects.
The present project is designed, therefore, to investigate how the intake of PUFA affects the immune defense as judged from already established in vitro systems viz. proliferation assays, cytokin formation, and natural killer activity in mononuclear cells from human blood obtained before and following dietary supplementation med PUFA. At the same time experiments will be performed to elucidate how the intake of PUFA matches the intake of natural antioxidants like for instance vitamin C, vitamin E, and flavonoids, in order to evaluate the correlation between the intake of PUFA and the oxidative defense mechanisms in vivo.
Finally, it will be elucidated how the intake of PUFA affects the capacity and profile of eicosanoid formation by the mononuclear cells in vitro, in preparation for in vivo determinations later on.