New Link Between Body Fat and Heart Disease
C-Reactive Protein Produced by Body Fat Raises Heart Disease Risk
Sept. 19, 2005 - A protein produced by human fat cells may explain why
overweight people face a higher risk of heart disease and stroke as well as
shed new light on the link between inflammation and these disorders.
A new study shows body fat cells produce a protein called C-reactive protein
(CRP) in response to inflammatory substances.
Researchers say CRP has previously been found only in the liver or within
blood vessel walls where it is produced in response to inflammatory triggers.
But these results suggest that body fat may also be capable of producing the
protein, which has been linked to an increased risk of heart disease and
"This study is the first to show how body fat participates in the
inflammatory process that leads to cardiovascular disease," says researcher
Edward T. H. Yeh, MD, chairman of the department of cardiology at the
University of Texas M.D. Anderson Cancer Center, in a news release.
Body Fat's Role in Heart Disease
Researchers say overweight people generally have elevated CRP levels, but
until now it hasn't been clear why.
In the study, published in the Journal of the American College of
Cardiology, researchers looked at whether body fat cells could produce
C-reactive protein under a variety of conditions in the lab.
The results showed that the fat cells produced inflammatory substances known
as cytokines, which resulted in inflammation and then triggered the production
of high levels of C-reactive protein.
In addition, researchers found resistin, a hormone produced by body fat
cells associated with diabetes and insulin resistance, also triggered the
production of CRP.
"If fat cells by themselves produce inflammatory signals that trigger
cells to produce CRPs, and if CRPs also produce biological effects on vascular
walls, that could explain the higher risk of cardiovascular disease," says
Drugs May Block Fat's Effect on CRP
Researchers then exposed the body fat cells that were producing C-reactive
protein to drugs used to treat heart disease, including aspirin and
cholesterol-lowering statins, and the diabetes drug Rezulin.
The results showed that treatment with these drugs significantly reduced the
production of C-reactive protein.
"We knew from studying patients that these drugs can reduce C-reactive
proteins, but now we have direct proof of their benefit," says Yeh.
Researchers say it's still not clear why body fat produces an inflammatory
response and what CRP's role in that process is.
"Inflammation is a very complicated phenomenon, but at least we now have
a few more clues as to what it does and how the damage it produces can be