Can an aspirin a day keep atherosclerosis at bay?

September 03, 2002

(Philadelphia, PA) - The original miracle drug, aspirin, continues to surprise medical scientists. While studies have proven that aspirin can prevent a second heart attack by thinning the blood, researchers at the University of Pennsylvania School of Medicine have shown that aspirin can also prevent heart attacks and stroke through an entirely different mechanism. Using laboratory models, the Penn researchers demonstrated that aspirin also lessens the inflammation associated with atherosclerosis and stabilizes athersclerotic plaque. Their findings are presented in the current issue of Circulation.

"The past decade has seen a lot of research indicating that atherosclerosis is a chronic inflammatory disease," said Domenico Praticò, MD, assistant professor in Penn's Department of Pharmacology. "Our findings show that aspirin not only decreases inflammation in the arteries and the growth of the atherosclerotic plaque, but it also beneficially alters the consistency of the plaque that remains."

Atherosclerosis, also known as hardening of the arteries, is a main cause of heart attacks and strokes, two leading causes of death in the United States. A variety of factors, including genetics and diet, spur the disease, which occurs as cholesterol-rich cells of the immune system accumulate inside of blood vessels. As these plaques grow, they cause the blood vessels to narrow. If a portion of the plaque breaks off it can induce the formation of a thrombus, a blood clot that could completely obstruct blood flow and cause a heart attack. Likewise, a portion of the thrombus could also travel through the bloodstream to the brain, where it could cause a stroke.

The Penn researchers found that low-dose aspirin leads to a change in the composition of the plaque, turning it from a soft foamy material to a harder material that is less likely to rupture.

"After aspirin, we find more collagen and smooth muscle cells in arterial plaque and significantly less cholesterol-rich cells," said Praticò. "Of course, it is better to have no plaque at all, but if you have plaque in your arteries, you would prefer it to stay put - where it will do the least harm."

Although the exact causes of atherosclerosis are unclear, researchers have known that the inflammation found in atherosclerosis is associated with increased levels of cellular inflammatory signals called cytokines. Plaque formation is also associated with increased levels in the aorta of a protein called NF-?B that controls the formation of these cytokines, stimulates the growth of immune cells and the accumulation of low-density lipoproteins (LDL) - also known as the 'bad' cholesterol. The Penn researchers have found that aspirin lowers the amount of both cytokines in the blood stream and the NF-?B in the aorta, suggesting a potent anti-inflammatory action of the drug.

Praticò and his colleagues hypothesize that these novel effects of low-dose of aspirin are independent from its known function as blood thinner.

Aspirin directly inhibits the cycloxygenase (COX) enzyme, which allows platelets in the blood to form clots. After aspirin blocks COX, it enables this enzyme to produce powerful anti-inflammatory molecules such as lipoxins, which in turn could inhibit the formation of cytokines - the very molecules that may stimulate atherosclerosis.

While Praticò recognizes more research needs to be done, aspirin could provide a potent, and inexpensive way to fight atherosclerosis. Low-dose aspirin has already been proven effective in preventing a second heart attack. There is a danger, however, taking large doses of aspirin, which can lead to gastrointestinal bleeding.

So, what constitutes a low-dose?

"Generally, we consider between 80mg and 250mg of aspirin to be 'low-dosages' - about the amount you would find in children's aspirin," said Praticò. "Of course, anyone considering taking a regimen of low-dose aspirin should consult a physician first." The research detailed in this study was supported by grants from the American Heart Association and the National Institutes of Health.
-end-


University of Pennsylvania School of Medicine

Related Heart Attack Articles from Brightsurf:

Top Science Tip Sheet on heart failure, heart muscle cells, heart attack and atrial fibrillation results
Newly discovered pathway may have potential for treating heart failure - New research model helps predict heart muscle cells' impact on heart function after injury - New mass spectrometry approach generates libraries of glycans in human heart tissue - Understanding heart damage after heart attack and treatment may provide clues for prevention - Understanding atrial fibrillation's effects on heart cells may help find treatments - New research may lead to therapy for heart failure caused by ICI cancer medication

Molecular imaging identifies link between heart and kidney inflammation after heart attack
Whole body positron emission tomography (PET) has, for the first time, illustrated the existence of inter-organ communication between the heart and kidneys via the immune system following acute myocardial infarction.

Muscle protein abundant in the heart plays key role in blood clotting during heart attack
A prevalent heart protein known as cardiac myosin, which is released into the body when a person suffers a heart attack, can cause blood to thicken or clot--worsening damage to heart tissue, a new study shows.

New target identified for repairing the heart after heart attack
An immune cell is shown for the first time to be involved in creating the scar that repairs the heart after damage.

Heart cells respond to heart attack and increase the chance of survival
The heart of humans and mice does not completely recover after a heart attack.

A simple method to improve heart-attack repair using stem cell-derived heart muscle cells
The heart cannot regenerate muscle after a heart attack, and this can lead to lethal heart failure.

Mount Sinai discovers placental stem cells that can regenerate heart after heart attack
Study identifies new stem cell type that can significantly improve cardiac function.

Fixing a broken heart: Exploring new ways to heal damage after a heart attack
The days immediately following a heart attack are critical for survivors' longevity and long-term healing of tissue.

Heart patch could limit muscle damage in heart attack aftermath
Guided by computer simulations, an international team of researchers has developed an adhesive patch that can provide support for damaged heart tissue, potentially reducing the stretching of heart muscle that's common after a heart attack.

How the heart sends an SOS signal to bone marrow cells after a heart attack
Exosomes are key to the SOS signal that the heart muscle sends out after a heart attack.

Read More: Heart Attack News and Heart Attack Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.