E-cigarette Aerosol Condensate leads to Impaired Coronary Endothelial Cell Health and Restricted Angiogenesis

Cardiovascular disease (CVD) is a leading cause of mortality worldwide, with cigarette smoking being a major preventable risk factor. Smoking cessation can be difficult due to the addictive nature of nicotine and the withdrawal symptoms following cessation. Electronic cigarettes (e-Cigs) have emerged as an alternative smoking cessation device, which has been increasingly used by non-smokers; however, the cardiovascular effects surrounding the use of e-Cigs remains unclear. This study aimed to investigate the effects of e-Cig aerosol condensate (EAC) (0mg and 18mg nicotine) in-vitro on human coronary artery endothelial cells (HCAEC) and in-vivo on the cardiovascular system using a mouse model of ‘e-vaping’. The results show a decrease in cell viability of HCAEC when exposed to EAC either directly or after exposure to conditioned lung cell media ( p  < 0.005). Reactive oxygen species and ICAM-1 expression were increased in HCAEC when exposed to EAC directly ( p  < 0.0005). ICAM-1 mRNA expression was increased (18mg vs control, p <  0.05), and immunostaining revealed upregulated anti-angiogenic markers, FKBPL, and endothelial cell marker, CD31, in murine hearts following exposure to electronic cigarette aerosol treatment. This study showed that even though e-Cigs are widely used for tobacco smoking cessation, these can negatively impact on endothelial cell health with a potential to lead to the development of cardiovascular disease. This process is visualised in Supplementary File 1.