But it is becoming increasingly clear that we should also think of type 2 diabetes in the context of immune function, Harvard scientists assert.
Guo-Ping Shi, Biochemist from the Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, began to suspect such a connection when, in a previous study, he found mast cells present in a variety of inflammatory vascular diseases.
Mast cells are immune cells that facilitate healing in wounded tissue, primarily by increasing blood flow to the site. However, in certain conditions mast cells build up to levels far beyond what the body needs. As a result these cells become unstable and eventually, like punctured trash bags, leak molecular "garbage" into the tissue. This can result in chronic inflammation that causes asthma and certain allergies.
As Shi and postdoctoral research fellow Jian Liu discovered, mast cells were far more abundant in fat tissue from obese and diabetic humans and mice than they were in normal weight fat tissue. This led to an obvious question: by regulating mast cells, could we then control the symptoms?
To find out, Shi and colleagues took a group of obese and diabetic mice and, for a period of two months, treated them with either ketotifen fumarate (also called Zaditor) or cromolyn, both over-the-counter allergy drugs.
"We knew from published research that both cromolyn and Zaditor help stabilize mast cells in people suffering from allergy or asthma," said Shi. "It's almost as if the drugs place an extra layer of plastic on the ripped trash bag. So it seemed like a logical place to begin."
The mice were divided into four groups. The first was the control group; the second group was simply switched to a healthy diet; the third was given cromolyn or ketoti
|Contact: David Cameron|
Harvard Medical School