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.
(January 2005)
