Exposure to Electronic Waterpipes Increases the Risk of Occlusive Cardiovascular Disease in C57BL/6J Mice

Abstract ID 93701 Poster Board 272 It is well documented that cardiovascular disease (CVD) is the leading cause of death in the United States and worldwide, with smoking being the most preventable cause. Additionally, most smokers die from thrombotic-based diseases, in which platelets play a major role. To this end, because of the proven harm of smoking, several novel tobacco products such as electronic(e)-waterpipe have been gaining popularity among different sectors of the population, partly due to the "false" safety claims. While many investigators have focused on the negative health effects of traditional cigarettes and e-cigarettes on the cardiovascular system, virtually little or nothing is known about e-waterpipes, which we explored. Thus, to investigate their occlusive CVD effects, we employed a whole-body mouse exposure model of e-waterpipe vape, and exposed C57BL/6J male mice (starting at 7 weeks of age) for one month, whereas the controls were exposed to clean air. Exposures took place seven times a week, according to the well-known Beirut protocol, which has been employed in many studies as it mimics real-life scenarios; specifically, 171 puffs of 530 ml volume of the e-liquid at 2.6s puff duration and 17s puff interval. Our in-vivo results showed that the e-waterpipe exposed mice had shortened bleeding, specifically an average of 83.75 relative to 244.6 seconds in the clean air control exposed mice. Moreover, the occlusion times were also reduced as a result of the e-waterpipe exposure, averaging 206.3 seconds, in comparison to 373.4 seconds in the controls, which indicates a prothrombotic phenotype. Cotinine, the metabolite for nicotine was only detected, as expected, in the e-waterpipe mice, at levels of 642 ng/ml, which are comparable to those seen in other ENDS in human users. As for the mechanism underlying this phenotype, we found that e-waterpipe exposed platelets exhibited enhanced agonist-triggered aggregation and dense granule secretion. Also, flow cytometry analysis of surface markers of platelet activation showed that both P-selectin and integrin GPIIb-IIIa activation were potentiated in the e-waterpipe exposed platelets, relative to the controls. With regard to inhibitory signaling, our data also showed that exposed platelets are more resistant to inhibition by prostacyclin. Finally, platelet spreading was also more pronounced in the exposed mice. Therefore, our findings document, for the first time, that e-waterpipe exposure does exert negative health effects in the context of thrombosis-based CVD, in part, via promoting platelet hyperreactivity. This work was supported by the National Institute of Environmental Health Sciences, the National Heart, Lung, And Blood Institute and the Eunice Kennedy Shriver National Institute of Child Health and Human Development of the National Institutes of Health under Awards Number R03ES030486, R01HL145053, R21ES029345, R56HL158730, R21HD105187, R21ES034512 and. The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health. This research was also supported by startup funds provided by the School of Pharmacy, Texas A&M University (to Khasawneh and Alshbool).