Smoking impairs blood vessel repair

Smokers are less able to repair damage to blood vessels because stem cells in their blood age more quickly, according to new research. The findings shed light on why tobacco use is linked to a higher risk of heart and circulatory disease, which is the leading cause of death worldwide, killing over 7 million people in 2011 alone. The study, published in Stem Cells , and funded by the Wellcome Trust , looked at stem cells called endothelial progenitor cells (EPCs), which circulate in the blood. These cells can develop into endothelial cells, which line our blood vessels. The role of EPCs is to repair damage to the vessels, which can otherwise lead to cardiovascular disease. The study found that EPCs were dysfunctional in both smokers and in patients with a smoking-linked inflammatory lung disorder called chronic obstructive pulmonary disease (COPD). Their EPCs had aged prematurely and showed damage in their DNA.