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Brief Background:

Nucleotides are most familiar as the building blocks of DNA and RNA. However nucleotides are by themselves or in combination with other molecules involved in almost all the activities of the cell, including catalysis, transfer of energy and mediation of hormone signals. Nucleotides are also essential for protein synthesis and tissue repair.
 

DNA

Deoxyribonucleic acid, DNA, which makes up the genetic material in cells, is comprised of units called nucleotides.

A nucleotide consists of a base, a sugar and a phosphate group. The major bases in DNA are the purines adenine (A) and guanine and the pyrimidines cytosine (C) and thymine (T). The sugar moiety of the nucleotide is 2'-deoxyribose.

The body has an on-going demand for new cell production, and must create cells at a rate as fast as that at which its cells die. To do this, a typical cell must double its mass and duplicate all of it contents in order to produce the two new daughter cells. This multiplication of a cell starts with the doubling of the information, namely the DNA. This is the ‘inter-phase’. A normal DNA consists of 3 billion nucleotides. Only after the multiplication of the DNA can the M-Phase start, which is where the two cell nuclei are formed and the cells starts to divide in two separate cells. Providing dietary sources of nucleotides has been shown to speed up the multiplication of certain cells.
 

RNA

Ribosenucleic acid, RNA, which is more abundant in active tissues than DNA by about an order of magnitude, is also comprised of nucleotide units. In the case of RNA, the major bases are again the purines adenine (A) and guanine (G), and the pyrimidines are cytosine (C) and uracil (U).

One of the major differences between DNA and RNA is the presence of uracil (U) in RNA and of thymine (T) in DNA. The other major difference is in the sugar moiety. In RNA, the sugar moiety of the nucleotide is ribose, whereas in DNA it is deoxyribose.
 

Other functions

Obviously nucleotides are an integral part of the structure of DNA and RNA and are essential compounds in the energy transfer system (i.e. in ATP, NADP, NADH)1,2, thus it has been assumed that they play an important role in carbohydrate, lipid, protein and nucleic acid metabolism3,4.

Other reported functions of nucleotides include:

  • Modification of intestinal microflora5
  • Influencing lymphocyte maturation, activation6 and proliferation7
  • Improvement of gastrointestinal tract repair after damage8
  • Enhance macrophage phagocytosis6
  • Facilitating liver recovery from ischaemia or surgery9
  • As a Component of co-enzymes10  

References:

  1. Carver, J. D. (1999). Dietary nucleotides: effects on the immune and gastrointestinal  systems. Acta Paediatr Suppl. 88:430,  83-8.

  2. Cosgrove, M. (1998). Perinatal and infant nutrition: Nucleotides. Nutrition 14 :7, 48-51.

  3. Yu, V. Y. H. (2002). Scientific rational and benefits of nucleotide supplementation of infant formula.

  4. Grimble, G. K. and Westwood, O. M. (2001). Nucleotides as immunomodulators in clinical nutrition. Curr Opin Clin Nutr Metab Care. 4:1, 57-64.

  5. Balmer, S. E., Hanvey, L. S. and Wharton, B. A. (1994). Diet and faecal flora in the newborn: nucleotides. Archives of Disease in Childhood - Fetal and Neonatal Edition 70, F137-F140.

  6. Gil, A. (2002). Modulation of the immune response mediated by dietary nucleotides. European Journal of Clinical Nutrition 56:S 3, S1-S4.

  7. Grimble, R.F. (2001). Nutritional modulation of immune function. Proc. Nutr. Soc. 60: 3, 389-397.

  8. Sukumar, P., Loo, A., Magur, E., Nandi, J., Oler, A. and Levine, R. A. (1997). Dietary supplementation of nucleotides and arginine promotes healing of small bowel ulcers in experimental ulcerative ileitis. Gastroenterology 42: 1530-1536.

  9. Palombo, J. D., Bowers, J. L., Clouse, M. E., McCullough, A., Forse, R. A. and Bistrian, B. R. (1993). Hepatic utilization of exogenous nucleotide precursors for restoration of ATP after cold ischemia in rats. Am. J. Clin. Nutr. 57, 420-7.

  10. Lerner, A. and Shamir, R. (2000). Nucleotides in Infant Nutrition: A Must or an Option. Israel Medical Association Journal 10: 2, 772-774.

See the Publictions section for our full archive of Nucleotide related scientific papers and references