Promise for Diabetics Seen in Newly Found Chemical

Rockefeller University researchers believe they have discovered a chemical that may prevent one type of blood vessel problem that causes serious kidney damage in diabetics.

The research team, headed by Dr. Michael Brownlee, called the chemical compound an “exciting clinical possibility” but cautioned that the potential therapy is based on laboratory and experimental animal studies that may not have application to humans for years.

Kidney damage, like one kind of blindness that is also a complication of diabetes, is the consequence of damage that occurs in a particular layer of cells forming the blood vessels that serve the kidneys. According to the American Diabetes Assn., diabetes-caused kidney failure accounts for about 25% of all patients on kidney dialysis.

Chemical Complex Formation

For many years the Rockefeller team has been exploring the possibility that excessive sugar in the blood of diabetics joins with proteins to form chemical complexes that lodge in a layer of the vessel wall called the basement membrane. There, they accumulate over the life of the patient.

The same process is believed to occur with normal aging, except at a much slower rate than in diabetics. It is believed that this process is one reason why vessel walls become less elastic with aging.

The Rockefeller scientists report in today’s issue of the journal Science that a chemical called aminoguanidine prevents the sugar-protein complexes from forming in tiny kidney blood vessels of diabetic rats.

They said the chemical inhibits a sequence of events that begins with the high sugar level and ends with a blockage of the blood vessels.

Brownlee is scheduled to present a report on the research Monday at the scientific sessions of the annual meeting of the American Diabetes Assn. in Anaheim.

‘Very Preliminary’

Dr. John Colwell, a Medical University of South Carolina expert who is vice president of the American Diabetes Assn., called the research “very interesting but very preliminary as far as application in man” is concerned.

In a telephone interview from Anaheim, Colwell said the big picture of blood vessel damage is more complex than that part caused by sugar-protein complexes.

He said other causes of vessel damage probably would still remain a threat even if a way is found to prevent damage due to the sugar-protein complexes.

Brownlee, however, said the researchers plan to apply for Food and Drug Administration approval of human trials with the drug within a year.