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Introduction to Glyconutritionals. Bill H. McAnalley, Ph.D. and Eileen Vennum, RAC. Science and medicine have long tried to break the biocode by which the cells of the body communicate with one another.
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Introduction to Glyconutritionals Bill H. McAnalley, Ph.D. and Eileen Vennum, RAC
Science and medicine have long tried to break the biocode by which the cells of the body communicate with one another.
The four major classes of biomolecules are proteins, nucleic acids, lipids (fats) and carbohydrates. For many years, scientists focused on proteins as the primary communication molecules.
In the 1960s, research first began to appear on glycoproteins*, protein molecules bound with carbohydrate molecules. *“Glyco” means “sweet” and refers to sugars, or carbohydrates.
Glycoprotein molecules coat the surface of every cell with a nucleus in the human body.
Glycolipids, carbohydrate molecules bound with lipid (fat) molecules, are another kind of glycoform, or glycoconjugate, found on cell surfaces
We now know that nature uses the carbohydrates on cell surface glycoconjugates as communication molecules.
Scientists have identified eight sugars found on human cell surface glycoforms that are involved in cellular recognition processes.* * Murray RK. Glycoproteins. In Murray RK, et al. (eds): Harper’s Biochemistry. Stamford, Appleton and Lange; 2000:677.
Just as four different shapes can be combined to make many letters, the different carbohydrate molecules combine within our bodies to make many cellular recognition “words”.
The significance of these sugar components of glycoproteins is well illustrated by the different blood types.
What raw materials does the body use to build the sugars to make glycoforms?The plants in our diet are the primary building blocks for the sugar portion of these molecules.
Enzymes are the tools the body uses to build the “glyco” portion of glycoforms. Figure E illustrates the enzymes needed to convert one form of sugar to another in the body.
The effectiveness of the enzymatic conversion system to create the needed sugar molecules is not absolute. Some individuals have inborn errors of metabolism. The conversion process also requires specific vitamins at certain steps, and these vitamins may be missing.
Until now, the fields of glycobiology and nutrition have never been adequately investigated together.
Although current nutrition textbooks stress the importance of essential vitamins, minerals, proteins (amino acids) and fats in great detail, sugars are currently recognized only as a source of energy.
Of the required eight sugars named in Harper’s Biochemistry, only glucose and galactose are addressed in the classic nutrition texts.
Glyconutritionals are dietary supplements designed to provide substrates for the body to use in building the “glyco” portion of glycoconjugates on cell surfaces. Glyconutritionals are designed to make the necessary sugars available to cells quicker and in greater quantity.
A November 1998 review concluded that disorders in glycosylation are much more common than originally thought. The author stated: “There is scant information on the availability of mannose in food, but dietary mannose is probably insufficient to supply all glycosylation.* *Freeze HH. Disorders in protein glycosylation and potential therapy: tip of an iceberg? J.Pediatr. 1998;133:593-600
We have only just begun to understand the biochemical story written in the sweet language of life, but what an exciting language to learn!
