E-cigarette flavored pods are increasing in use among young adults. Although marketed as a safer alternative to conventional cigarettes, the health effects of e-cigarette flavored pods are unknown. We hypothesized that e-cigarette flavored pods would cause oxidative stress, barrier dysfunction, and an inflammatory response in monocytes and lung epithelial cells. JUUL pod flavors (Fruit Medley, Virginia Tobacco, Cool Mint, Crème Brulee, Cool Cucumber, Mango, and Classic Menthol) and similar pod flavors (Just Mango-Strawberry Coconut and Caffé Latte) were tested. These pod flavors generated significant amounts of acellular ROS and induced significant mitochondrial superoxide production in bronchial epithelial cells (16-HBE). Lung epithelial cells (16-HBE, BEAS-2B) and monocytes (U937) exposed to various pod aerosols resulted in increased inflammatory mediators, such as IL-8 or PGE2. JUUL pod flavors, Crème Brulee and Cool Cucumber, caused epithelial barrier dysfunction in 16-HBE cells. Moreover, tested flavors also showed DNA damage upon exposure in monocytes. We determined the chemical constituents present in various flavors. Our data suggest that these constituents in flavored pods induce oxidative stress, inflammation, epithelial barrier dysfunction, and DNA damage in lung cells. These data provide insights into the regulation of e-cigarette flavored pods, as well as constituents in these flavors.

The Centers for Disease Control declared e-cigarette, or vaping, product use-associated lung injury (EVALI) a national outbreak due to the high incidence of emergency department admissions and deaths. We have identified chemical constituents in e-cig counterfeit cartridges and compared these to medical-grade and CBD containing cartridges. Apart from vitamin E acetate (VEA) and tetrahydrocannabinol (THC), other potential toxicants were identified including solvent-derived hydrocarbons, silicon conjugated compounds, various terpenes, pesticides/plasticizers/polycaprolactones, and metals. This study provides additional insights into the chemicals associated with EVALI cartridges and thus may contribute to the underlying disease mechanism of acute lung injury.

The placenta is the principal regulator of the in utero environment, and disruptions to this environment can result in adverse offspring health outcomes. To better characterize the impact of in utero perturbations, we assessed the influence of known environmental pollutants on the expression of microRNA (miRNA) in placental samples collected from the National Children's Study (NCS) Vanguard birth cohort. This study analyzed the expression of 654 miRNAs in 110 term placentas. Environmental pollutants measured in these placentas included dichlorodiphenyldichloroethylene (DDE), bisphenol A (BPA), polybrominated diphenyl ethers (PBDEs), polychlorinated biphenyls (PCBs), arsenic (As), mercury (Hg), lead (Pb), and cadmium (Cd). A moderated t-test was used to identify a panel of differentially expressed miRNAs, which were further analyzed using generalized linear models. We observed 112 miRNAs consistently expressed in >70% of the samples. Consistent with the literature, miRNAs located within the imprinted placenta-specific C19MC cluster, specifically mir-517a, mir-517c, mir-522, and mir-23a, are among the top expressed miRNA in our study. We observed a positive association between PBDE 209 and miR-188-5p and an inverse association between PBDE 99 and let-7c. Both PCBs and Cd were positively associated with miR-1537 expression level. In addition, multiple let-7 family members were downregulated with increasing levels of Hg and Pb. We did not observe DDE or BPA levels to be associated with placental miRNA expression. This is the first birth cohort study linking environmental pollutants and placental expression of miRNAs. Our results suggest that placental miRNA profiles may signal in utero exposures to environmental chemicals.

Electronic cigarette (e-cig) usage has risen dramatically worldwide over the past decade. While they are touted as a safe alternative to cigarettes, recent studies indicate that high levels of nicotine and flavoring chemicals present in e-cigs may still cause adverse health effects. We hypothesized that an e-liquid containing a mixture of tobacco, coconut, vanilla, and cookie flavors would induce senescence and disrupt wound healing processes in pulmonary fibroblasts. To test this hypothesis, we exposed pulmonary fibroblasts (HFL-1) to e-liquid at varying doses and assessed cytotoxicity, inflammation, senescence, and myofibroblast differentiation. We found that e-liquid exposure caused cytotoxicity, which was accompanied by an increase in IL-8 release in the conditioned media. E-liquid exposure resulted in elevated senescence-associated beta-galactosidase (SA-β-gal) activity. Transforming growth factor-β1 (TGF-β1) induced myofibroblast differentiation was inhibited by e-liquid exposure, resulting in decreased α-smooth muscle actin and fibronectin protein levels. Together, our data suggest that an e-liquid containing a mixture of flavors induces inflammation, senescence and dysregulated wound healing responses.

The effects of tetrahydrocannabinol (THC) on several parameters of macrophage function in vitro were assessed. Delta 9 THC added to cultures of normal mouse peritoneal cells in vitro affected the ability of the cells to spread on glass surfaces and also had some effect on their ability to phagocytize yeast. These effects were dose related. A concentration of 20 micrograms of THC almost completely inhibited macrophage spreading, but it also decreased viability and the total number of these cells. Doses of 10 or 5 micrograms of THC also inhibited spreading but had little effect on cell viability or number. A dose of 1.0 microgram of THC had some inhibitory effect on spreading and the lowest dose affecting spreading appeared to be about 0.05 micrograms per culture. Higher doses of THC were necessary to inhibit phagocytosis of yeast particles as determined by direct microscopic examination or use of radiolabeled yeast as the test particles. These results indicate that several readily measured functions of macrophages may be suppressed by THC.