A new study shows how and why a high-fat
diet and obesity are linked to type 2 diabetes.
Researchers at the University of California, San Diego
have found a molecular connection between the high-fat
Western-style diet and the disruption of insulin production.
A single enzyme, called GnT-4a, enables the beta cells
in the pancreas to sense blood glucose levels and produce
the appropriate amount of insulin.
Studies with mice show that this enzyme is suppressed
by a high-fat diet, resulting in diabetes, the researchers
said.
The study appears in the Dec. 29 issue of the journal
Cell.
Early in the disease, diabetes patients produce insufficient
insulin that results in hyperglycemia, or elevated blood
glucose. Beta cells overcompensate and produce too much
insulin, resulting in full-blown type 2 diabetes. More
than 200 million people worldwide have been diagnosed
with the disease, 20 million in the United States alone.
"In fact, the likelihood that obesity will lead to diabetes
is so common that this epidemic is sometimes referred
to as 'diabesity,' " Jamey Marth, a professor of cellular
and molecular medicine at UCSD and an investigator with
the Howard Hughes Medical Institute, said in a prepared
statement.
High levels of insulin have also been implicated in contributing
to other diseases such as cancer, cardiovascular disease
and stroke. The researchers said new forms of treatment
may include inhibiting the GnT-4a gene to reduce insulin
production.
