Enzyme Study Links Fatty Diets to Diabetes

Diets high in fat can disrupt blood sugar levels and trigger diabetes, researchers said Wednesday in a study that helps explain the link between obesity and a disease typically linked to sugar.

Fatty foods can suppress an enzyme crucial to the production of insulin, which regulates sugar in the blood, scientists at UC San Diego said.

Obesity has long been linked to Type 2 diabetes, the most common form of the disease, in which the body does not make enough insulin or cannot properly use it.

In the United States, two out of three adults are overweight or obese. Experts have said obese people are up to 80 times more likely to develop diabetes, and both conditions are on the rise.

The findings, published in the journal Cell, offer another explanation of exactly how the two are linked.

“We have discovered ... a molecular trigger which begins the chain of events leading from hyperglycemia to insulin resistance and Type 2 diabetes,” said Jamey Marth, a professor of cellular and molecular medicine.

“This finding suggests new approaches to the prevention and treatment of diabetes,” said Marth, an investigator with the nonprofit Howard Hughes Medical Institute, which helped fund the research.

Marth and his colleagues studied the glycosyltransferase enzyme, which helps the pancreas sense how much sugar is in the blood and release enough insulin to help process it.

In a study of normal mice that were fed a fatty diet, researchers found that the enzyme was repressed, leaving pancreatic cells unable to sense sugar levels and leading to diabetes.

“Our findings suggest that the current human epidemic in Type 2 diabetes may be a result of GnT-4a enzyme deficiency,” said Marth, adding that people who inherit a faulty gene may also be vulnerable to diabetes.

It may also play a role in the early onset of Type 2 diabetes in children and teenagers, according to the study, which was also sponsored by the National Institutes of Health.