Monday, July 30, 2007

Air Pollution the Culprit in Cardiovascular Disease

A new scientific study, published in the July 26th edition of the online journal Genome Biology, shows how fine particles in air pollution conspire with artery-clogging fats to switch on the genes that cause blood vessel inflammation and that lead to cardiovascular disease. This UCLA team links diesel exhaust to hardening of the arteries, which significantly increases one’s risk for heart attack and stroke. If you are one of the millions with high cholesterol, you might want to stay away from air pollution.

There's a hidden synergy behind these diesel exhaust particles and artery-clogging fats; together, they have a much larger effect than individually when they switch on the genes that cause blood vessel inflammation and eventually cardiovascular disease. The combination wreaks cardiovascular havoc far beyond what’s caused by the diesel or cholesterol alone.

The researchers set up a scenario to investigate the interaction between diesel exhaust particles and the fatty acids found in low-density lipoprotein (LDL) cholesterol — the “bad” type of cholesterol that leads to artery blockage.

“Diesel particles are coated in chemicals containing free radicals, and the fatty acids in LDL cholesterol generate free radicals during metabolism in the cells,” said first author Ke Wei Gong, a UCLA cardiology researcher. “We wanted to measure what happens when these two sources of oxidation come into contact.”

The scientists combined the pollutants and oxidized fats and cultured them with cells from the inner lining of human blood vessels. A few hours later, the team extracted DNA from the cells for genetic analysis. They saw that the diesel particles and oxidized fats had worked in tandem to activate the genes that promote cellular inflammation — a major risk factor for atherosclerosis. It is vascular inflammation that leads to cholesterol deposits and clogged arteries, which can give rise to blood clots that trigger heart attack or stroke.

For anyone experiencing high cholesterol, getting out of traffic and into the country would be a very, very healthy idea. Although it wasn't mentioned in the article, their research seems to suggest that anti-oxidants in supplement form would be beneficial.

Another research report on the same topic, this one from Germany and published in the journal Circulation is linked to the headline of today's topic.