COLUMBUS, Ohio Insulin resistance, the hallmark of type 2 diabetes and a condition often associated with obesity, is paradoxically also an apparent contributor to muscle wasting and severe fat loss that accompanies some cancers, according to new research.
And in an animal study, a diabetes drug that promotes insulin sensitivity slowed the progression of muscle wasting and fat loss, the main consequences of a syndrome called cachexia, in mice with colon cancer tumors.
Though it remains unknown whether that drug, rosiglitazone, has potential to prevent cachexia in humans with cancer, the finding led researchers to believe that curbing insulin resistance in cancer patients could improve their quality of life.
Research suggests that cachexia is responsible for between one-fifth and one-third of all cancer deaths.
The insulin resistance and cachexia both appear to be connected to inflammation induced either by tumors themselves or by secretions from tumors that activate an immune response, the researchers say.
"Insulin resistance usually follows obesity. In this case, it precedes uncontrollable fat loss," said Martha Belury, senior author of the study and a professor of human nutrition at Ohio State University. "The insulin resistance is the process we've identified that occurs soon after tumors form. So if we can change that part of the disease, we might be able to change the progression and trajectory of how fast fat and muscle are lost as well. That's our goal."
The research appears online and is scheduled for future print publication in the International Journal of Cancer.
Belury and colleagues conducted two experiments. In the first, the researchers sought to demonstrate that animals developed insulin resistance shortly after they developed cancer and before muscle and fat loss became evident. In the second, they tested the effectiveness of the insulin sensitizing drug rosiglitazone again
|Contact: Martha Belury|
Ohio State University