Too sweet for your own good

Author: John Monczunski

A spoonful of sugar may make the medicine go down, but when too much glucose is afloat in the bloodstream bad things happen. Renal failure and blindness, for instance, which can result from diabetes, has been associated with so-called “non-enzymatic glycated proteins,” in which glucose has been added willy-nilly to the protein.

“Normally the body uses a system of enzymes to regulate how sugars are added to certain proteins,” explains Notre Dame professor of chemistry Anthony Serriani. "But when there is an overload of glucose in the blood, it is uncontrolled by the enzyme system and gets added by accident with disastrous effects.

“The excess glucose in the bloodstream reacts with certain amino acid groups on the surface of the protein to form what chemists call an ‘Amadori adduct,’ a condensation between the sugar and the protein,” Serianni says. “This then can morph into a host of unregulated structures that negatively affect the protein’s normal function.” Where the protein is situated in the body determines what problem may occur. For instance, in the eye, it can be blindness; in the liver, liver damage.

Working with scientists from Vanderbilt University, Serianni is using an analytical technique known as NMR spectroscopy to determine precisely what happens to glucose after it attaches to protein molecules. The ultimate goal, he says, is to use that knowledge to develop a drug which can interfere with the process, preventing the bodily damage.