Immunonutrition - nutrients with immunomodulating action, part 2: Nucleotides and polyunsaturated fatty acids

Nucleotides and nucleotide components are multifunctional with regard to th e immune system. A deficiency of these substrates is therefore associated w ith a general dysfunction of immunocompetent cells. In healthy adults, endo genous synthesis is sufficient; supply with food is not required. In certai n clinical situations and in phases of heavy growth, however, the increased need of nucleotides is not always met endogenously; in these cases, nucleo tides and their components become indispensable nutrients which should be s upplied with food. Polyunsaturated fatty acids of the omega-3- and omega-6 family regulate the immune response in different ways. As part of cell membrane phospholipids, they influence membrane fluidity and thus the activity of receptors and tr ansport systems. As precursors of partly antagonistic eicosanoids, they con tribute to the regulation of inflammatory processes, platelet aggregation a nd vascular tone. A certain ratio of omega-3- to omega-6 Fatty acids in the daily diet (ca. 5 : 1) is recommended for both preventive and therapeutica l purposes.