Navigation Links
Researchers show how air pollution can cause heart disease

New York University School of Medicine researchers provide some of the most compelling evidence yet that long-term exposure to air pollution--even at levels within federal standards--causes heart disease. Previous studies have linked air pollution to cardiovascular disease but until now it was poorly understood how pollution damaged the body's blood vessels.

In a well-designed mouse study, where animals breathed air as polluted as the air in New York City, the researchers pinpointed specific mechanisms and showed that air pollution can be particularly damaging when coupled with a high-fat diet, according to new research published in the December 21 issue of JAMA.

"We established a causal link between air pollution and atherosclerosis," says Lung Chi Chen, Ph.D., Associate Professor of Environmental Medicine at NYU School of Medicine and a lead author of the study. Atherosclerosis--the hardening, narrowing, and clogging of the arteries--is an important component of cardiovascular disease.

The study, done in collaboration with the Mount Sinai School of Medicine and University of Michigan, looked at the effects of airborne particles measuring less than 2.5 microns, referred to as PM2.5, the size linked most strongly with cardiovascular disease. The emissions arise primarily from power plants and vehicle exhaust. The US Environmental Protection Agency (EPA) has regulated PM2.5 since 1997, limiting each person's average exposure per year to no more than 15 micrograms per cubic meter. These tiny particles of dust, soot, and smoke lead to an estimated 60,000 premature deaths every year in the United States.

Dr. Chen and his colleagues divided 28 mice, which were genetically prone to developing cardiovascular disease, into two groups eating either normal or high-fat diets. For the next six months, half of the mice in each feeding group breathed doses of either particle-free filtered air or concentrated air containing PM2.5 at levels that ave raged out to 15.2 micrograms per cubic meter. This amount is within the range of annual EPA limits and equivalent to air quality in urban areas such as New York City.

The researchers then conducted an array of tests to measure whether the PM2.5 exposure had any impact on the mice's cardiovascular health. Overall, mice who breathed polluted air fared worse than those inhaling filtered air. But when coupled with a high-fat diet, the impact of PM2.5 exposure was even more dramatic. The results added up to a clear cause and effect relationship between PM2.5 exposure and atherosclerosis, according to the study.

On the whole, mice breathing polluted air had far more plaque than those breathing filtered air. In cross sections taken from the largest artery in the body--the aorta--mice on normal diets and exposed to PM2.5 had arteries 19.2 percent filled with plaque, the fatty deposits that clog arteries. The arteries of those breathing particle-free air were 13.2 percent obstructed. Among high-fat diet mice, those exposed to PM2.5 had arteries that were 41.5 percent obstructed by plaque, whereas the arteries of the pollution-free mice were 26.2 percent clogged. In both normal and high-fat diet mice, PM2.5 exposure increased cholesterol levels, which are thought to exacerbate plaque buildup.

Though findings for increased plaque among mice eating normal diets were not statistically significant, Dr. Chen believes that future research on larger numbers of animals will solidify the trend. "Even with the low-fat diet, there's still something there. So that is something to think about," he says. He suspects that PM2.5 exposure could also greatly affect even people who do not eat high-fat diets.

Mice exposed to PM2.5 also appeared prone to developing high blood pressure, another element of cardiovascular disease, because their arteries had become less elastic. To measure tension in the arteries, the researchers tested how the neurotransmitters sero tonin and acetylcholine affected the aortic arches of PM2.5-exposed mice differently than those of controls. The arteries taken from exposed mice were less elastic than the control group, constricting more in the presence of serotonin and relaxing less in response to acetylcholine. Once again, the mice fed high-fat diets suffered the most pronounced effects from breathing polluted air.

Finally, the researchers also examined various measures of vascular inflammation, which is involved in atherosclerosis on a number of levels. In the aortas of PM2.5–exposed mice, for example, they found increased levels of macrophages, immune cells that are an important ingredient in plaque deposits and also active participants in a biochemical pathway related to inflammation. The study revealed several signs that this pathway was more active, strengthening the connection between airborne particles and cardiovascular disease.


'"/>

Source:New York University Medical Center and School of Medicine


Related biology news :

1. Researchers discover way to make cells in the eye sensitive to light
2. Researchers find how protein allows insects to detect and respond to pheromones
3. Researchers Uncover Key Step In Manufacture of Memory Protein
4. Researchers reveal the infectious impact of salmon farms on wild salmon
5. Researchers identify target for cancer drugs
6. Researchers discover molecule that causes secondary stroke
7. Researchers find missing genes of ancient organism
8. Researchers trace evolution to relatively simple genetic changes
9. Researchers add new tool to tumor-treatment arsenal
10. UF Researchers Map Bacterial Proteins That Cause Tooth Loss
11. VCU Researchers Identify Networks Of Genes Responding To Alcohol In The Brain
Post Your Comments:
*Name:
*Comment:
*Email:


(Date:12/16/2016)... Dec. 16, 2016   IdentyTechSolutions America LLC ... products and solutions and a cutting-edge manufacturer of ... it is offering seamless, integrated solutions that comprise ... products. The solutions provide IdentyTech,s customers with combined ... facilities from crime and theft. "We ...
(Date:12/15/2016)... Dec 15, 2016 ... Research and Markets has announced the addition of ... The report forecasts the global military biometrics market to ... The report has been prepared based on an in-depth market analysis ... its growth prospects over the coming years. The report also includes a ...
(Date:12/8/2016)... Research Future published a half cooked research report on Mobile Biometric ... Market is expected to grow over the CAGR of ~35% during ... ... Mobile Biometric Security and Service Market is increasing at a ... security from unwanted cyber threats. The increasing use of mobile device ...
Breaking Biology News(10 mins):
(Date:1/19/2017)... , Jan. 18, 2017 Acupath Laboratories, ... announces the formation of an Executive Committee that will ... beyond. John Cucci , a 15-year ... from Director of Business Development to Chief Sales ... Mr. Cucci served in senior sales leadership roles at ...
(Date:1/18/2017)... Portland, OR (PRWEB) , ... January 18, 2017 ... ... modules that provide essential device-to-computer interconnect using USB or PCI Express, announced the ... Altera Cyclone V E FPGA into a compact business-card sized form factor suitable ...
(Date:1/18/2017)... , Jan. 18, 2017   Boston Biomedical ... compounds designed to target cancer stemness pathways, will feature ... compound, napabucasin, at the 2017 ASCO Gastrointestinal Cancers Symposium, ... . Napabucasin is an orally-administered ... targeting STAT3. i Cancer stem cells (CSCs) possess ...
(Date:1/18/2017)... Jan. 18, 2017   Parent Project Muscular Dystrophy ... end Duchenne muscular dystrophy (Duchenne) , today announced ... Jersey Institute of Technology (NJIT) and Talem Technologies (Talem) ... robotic technology to assist people living with Duchenne. ... technology – an embedded computer, software, a force sensor ...
Breaking Biology Technology: