The Effects of Smoking on Levels of Endothelial Progenitor Cells and Microparticles in the Blood of Healthy Volunteers

Abstract

BackgroundCigarette smoking, both active and passive, is one of the leading causes of morbidity and mortality in cardiovascular disease. To assess the impact of brief smoking on the vasculature, we determined levels of circulating endothelial progenitor cells (EPCs) and circulating microparticles (MPs) following the smoking of one cigarette by young, healthy intermittent smokers.Materials and Methods12 healthy volunteers were randomized to either smoking or not smoking in a crossover fashion. Blood sampling was performed at baseline, 1, 4 and 24 hours following smoking/not smoking. The numbers of EPCs and MPs were determined by flow cytometry. MPs were measured from platelets, leukocytes and endothelial cells. Moreover, MPs were also labelled with anti-HMGB1 and SYTO 13 to assess the content of nuclear molecules.ResultsActive smoking of one cigarette caused an immediate and significant increase in the numbers of circulating EPCs and MPs of platelet-, endothelial- and leukocyte origin. Levels of MPs containing nuclear molecules were increased, of which the majority were positive for CD41 and CD45 (platelet- and leukocyte origin). CD144 (VE-cadherin) or HMGB1 release did not significantly change during active smoking.ConclusionBrief active smoking of one cigarette generated an acute release of EPC and MPs, of which the latter contained nuclear matter. Together, these results demonstrate acute effects of cigarette smoke on endothelial, platelet and leukocyte function as well as injury to the vascular wall.

Extracellular vesicles released in response to respiratory exposures: implications for chronic disease

“…The same CSE-EV were less potent inducers of monocyte adhesion to endothelial cells than EV secreted by unexposed cells , questioning a role of CSE-induced EV in immune cell recruitment. Several human and animal studies that assessed in vivo effects of respiratory exposures were not able to link changes in circulating EV to alterations in inflammatory markers (Emmerechts et al 2012a(Emmerechts et al , 2012bLevanen et al 2013;Mobarrez et al 2014). Several investigators even found that smokers displayed decreased concentrations of circulating PS + EV compared to nonsmokers (Badrnya, Baumgartner, and Assinger 2014;Enjeti et al 2017;Grant et al 2011).…”

“…Several investigators even found that smokers displayed decreased concentrations of circulating PS + EV compared to nonsmokers (Badrnya, Baumgartner, and Assinger 2014;Enjeti et al 2017;Grant et al 2011). In part, the failure to detect proinflammatory changes in EV in response to respiratory toxicants in vivo may be due to (1) use of relatively mild and acute exposures (Levanen et al 2013;Mobarrez et al 2014) or (2) the fact that current methods are not sensitive enough to detect subtle changes in EV and inflammatory mediators in study populations without clinical disease.…”

“…Another potential explanation is that all in vitro studies investigated the effect of a single acute CS exposure, whereas exposure in human smokers is repeated over a long time, and adaptation may take place in healthy individuals. To elucidate whether acute human CS exposure results in increased circulating PS+ EV, PS+ EV should be analyzed in acute exposure studies such as those performed by Heiss et al (2008) and Mobarrez et al (2014). Finally, slower centrifugation speeds were used for EV isolation in the in vivo studies (10,000 × g) than in the in vitro experiments (approximately 100,000 × g), which may have resulted in analysis of different EV subpopulations.…”

“…Several investigators found that respiratory exposures are associated with increased circulating platelet-derived EV (Emmerechts et al 2012a;Mobarrez et al 2014;Pergoli et al 2017;Xu et al 2013), which are thought to reflect platelet activation and promote coagulation. Exposure to occupational and environmental PM was reported to produce changes in circulating EV microRNA cargo that were predicted to promote coagulation based upon bioinformatics analyses (Pavanello et al 2016;Pergoli et al 2017).…”

“…CS exposure of mice and rats enhanced circulating endothelial-derived EV levels (Liu et al 2014;Serban et al 2016). Transient exposure of healthy humans to second-hand or mainstream CS, and chronic smoking are associated with elevated numbers of circulating endothelial-derived EV (Gordon et al 2011;Heiss et al 2008;Mobarrez et al 2014). Smoking cessation reverts the rise in endothelial-derived EV, but only in individuals in whom lung damage has not yet been established (Strulovici-Barel et al 2016).…”