Got high cholesterol? You might want to stay away from air pollution.
Thats the message of a new UCLA study linking diesel exhaust to atherosclerosis, or hardening of the arteries, which significantly increases ones risk for heart attack and stroke. Published in the July 26 edition of the online journal Genome Biology, the findings are the first to explain how fine particles in air pollution conspire with artery-clogging fats to switch on the genes that cause blood vessel inflammation and lead to cardiovascular disease.
When you add one plus one, it normally totals two, said principal investigator Dr. Andr Nel, chief of nanomedicine at the David Geffen School of Medicine at UCLA and a researcher at UCLAs California NanoSystems Institute. But we found that adding diesel particles to cholesterol fats equals three. Their combination creates a dangerous synergy that wreaks cardiovascular havoc far beyond whats 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.
In particular, the team was interested in how oxidation cell and tissue damage resulting from exposure to molecules known as free radicals contributes to inflammation and artery disease. Free radicals enter the body through small particles present in polluted air and are also byproducts of normal processes, such as the metabolic conversion of food into energy.
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.