Insulin resistance of arteries of mice appears to accelerate atherosclerosis.

Earlier studies showed that in the context of systemic insulin resistance, blood vessels become resistant, too. Doctors also knew that insulin resistance and the high insulin levels to which it leads are independent risk factors for vascular disease. But it wasn't clear if arteries become diseased because they can't respond to insulin or because they get exposed to too much of it.

Now comes evidence in favor of the former explanation. Rask-Madsen along with George King and their colleagues find that mice prone to atherosclerosis fare much worse when the linings of their arteries can't respond to insulin. The animals' insulin-resistant arteries develop plaques that are twice the size of those on normal arteries.

Insulin-resistant blood vessels don't open up as well, and levels of a protein known as VCAM-1 go up in them, too.

VCAM-1 belongs to a family of adhesion molecules, Rask-Madsen explained. "It sits on the endothelium and binds white blood cells." Those cells can enter the artery wall, where they start taking up cholesterol, and an early plaque is born.

"The results provide definitive evidence that loss of insulin signaling in the endothelium, in the absence of competing systemic risk factors, accelerates atherosclerosis," the researchers conclude.

Take a glance at the risk factors for type II insulin-resistant diabetes and consider steps you can take to reduce your risks. The risk factors are very similar to the risk factors for heart disease and stroke.

Also seem my recent related post on how aging blood vessels lose the ability to dilate in response to increased insulin and how that probably causes elderly muscle loss.