Dietary Nucleotides in Neurodegenerative Diseases

There has been an explosion of scientific interest in the health enhancing role of specific foods or physiologically-active food components, the so-called functional foods. It is believed that diet play an important role against neurodegenerative diseases and some functional foods can help to prevent the onset of the disease or reduce the degree of progression, once established. The nutritional recommendations for most neurodegenerative diseases are an adequate intake of energy and protein, as well as vitamin E, for its antioxidant character, and vitamins of the B group (folic acid, B6, B12, choline), for its ability to prevent the accumulation of homocysteine. Other physiologically-active food components such as polyunsaturated fatty acids and gangliosides have been postulated.

During the last three decades numerous evidences of the benefits of dietary nucleotides have accumulated. Exogenous nucleotides, which are absorbed as nucleosides, are incorporated into the intracellular pool and thereby increase the availability of metabolites involved in the generation of energy (ATP GTP, etc.) and in many biosynthetic processes (CDP-choline, UDP-glucose, etc.). On the other hand, the nucleotide pool is closely related to rRNA and in lesser extent mRNA pools and the lack of dietary nucleotides originates a metabolic deactivation. In addition, nucleotides have an active role as modulators of gene expression, not only of the elements involved in its metabolism (enzymes, transporters, etc.), but a variety of genes not related (for example with the expression of genes of the inflammation and apoptosis), by a mechanism that involves changes in many transcription factors. Of especial importance are the functions as signaling molecules, the so call purinome or nucleotidome, is a complex interplay among ligands, degrading enzymes, receptors and transporters not fully characterized yet . Through the above mechanisms, dietary nucleotides play an important role in the development of the immune system and are also important for proliferation and tissue development, particularly for tissues with a rapid turnover, as the skin, intestinal mucosa, bone marrow cells and lymphocytes. They have been considered as semi-essential nutrients and food supplemented with them considered as functional food. Currently, there are numerous preparations containing nucleotides for infant and parenteral nutrition.