Readers may recall our previous posts about research linking some vape flavoring additives with adverse health consequences. Now a new first of its kind study using endothelial stem cells* has been published specifically linking some vape flavoring additives (esp. menthol and cinnamon) with a potential increased risk for heart problems.
*Endothelial cells are the main type of cell found in the inside lining of blood vessels, lymph vessels and the heart.
Study methods overview
Endothelial stem cells were derived from three healthy individuals and a subject population consisting of five healthy non-smokers, five active cigarette smokers, two dual users of e-cigarettes and cigarettes, and two sole users of e-cigarettes. All subjects were healthy individuals free of other major cardiovascular risk factors.
In laboratory dishes, researchers grew cells that normally line healthy human blood vessels. They exposed the cells to six different e-cigarette flavorings, testing if the flavors — and not just the nicotine — caused any effects.
They also tracked what happened when those cells were bathed in blood taken from people right after they had an e-cigarette, the way chemicals from vaping would make their way to the cardiovascular system. They also compared the cells’ exposure to blood from nonsmokers and people who smoked a regular cigarette.
Study results overview
Vaping and some flavorings, even without nicotine, triggered blood vessel dysfunction that can increase the risk of heart disease. All six flavored e-liquids tested** had varying effects on cell survival and the presence of pro-inflammatory markers that are known to play a critical role in the development of vascular disease…Cinnamon and menthol appeared to be the most toxic. Overall, cells showed signs of damage and were inflamed, less able to form new blood vessels or heal wounds.
**Fruit-flavored, sweet tobacco with undertones of caramel and vanilla-flavored, tobacco-flavored Red Oak Tennessee Cured, and sweet-flavored Butter Scotch all had moderate toxic effects on the cells, with the strongest toxic effect coming from the cinnamon-flavored Marcado. They also found menthol tobacco-flavored Tundra had a strong toxic effect at 1 percent dose of concentration with or without nicotine.
Journal Reference: Wu, J.C. et al. (2019) Modeling Cardiovascular Risks of E-Cigarettes With Human-Induced Pluripotent Stem Cell–Derived Endothelial Cells. Journal of the American College of Cardiology.