A new study from researchers at the University of Bristol’s Medical Research Council Integrative Epidemiology Unit (MRC IEU) revealed that there are significant differences in how the human heart reacts to e-cigarette smoke and conventional tobacco (cigarette) smoke.
The study titled “Cigarette smoke but not electronic cigarette aerosol activates a stress response in human coronary artery endothelial cells in culture” was published on April 2016 in the journal Drug and Alcohol Dependence. The research studied how human coronary artery endothelial cells (HCAEC) – cells found in the arteries of the heart – responded when exposed to either e-cigarette aerosol or conventional cigarette smoke.
Cigarette smoking is the most significant preventable cause of premature death in the U.S., accounting for over 440,000 of the nearly 2.4 million annual deaths. Cigarette smokers have higher risks of developing chronic disorders, including several types of cancer, and chronic obstructive pulmonary disease (COPD). Atherosclerosis, which is a buildup of fatty substances in the arteries, is the top life-threatening condition associated with smoking, and many studies showed that cigarette smoking is a major cause of coronary heart disease.
The study tested cigarette smoke extract (CSE) from a conventional cigarette and electronic cigarette aerosol extract (eCAE) from an e-cigarette. Both extracts were passed through a culture of heart cells. Subsequently, gene expression patterns in these cells were examined to determine if cells showed any stress response to cigarette smoke or e-cigarette aerosol.
“The past few years have seen a rapid growth in the use of e-cigarettes, which deliver nicotine via inhaled aerosol. It’s thought that e-cigarettes are unlikely to be as harmful as conventional cigarettes, but little data exists to show their relative harms, or the long term effects of e-cigarette use. Therefore, research into these biological effects is critical. Our study looked at the stress response in heart cells in response to cigarette smoke and e-cigarette aerosol,” said Professor Marcus Munafò, co-author of the study, in a press release.
The team found evidence suggesting that the use of e-cigarettes as a substitute for conventional cigarettes is likely to reduce immediate tobacco-related harm, at least in terms of cardiovascular harm.
“We found the cells showed a stress response from the cigarette smoke extract, but not from the electronic cigarette aerosol extract. This result suggests tobacco smokers may be able to reduce immediate tobacco-related harm by switching from conventional cigarettes to e-cigarettes,” concluded Professor Munafò.