Nicotine and Microvascular Responses in Skeletal Muscle from Acute Exposure to Cigarettes and Vaping.

Despite claims of safety or harm reduction for electronic cigarettes (E-cig) use (also known as vaping), emerging evidence indicates that E-cigs are not likely safe, or necessarily safer than traditional cigarettes, when considering the user's risk of developing vascular dysfunction/disease. E-cigs are different from regular cigarettes in that E-cig devices are highly customizable, and users can change the e-liquid composition (such as the base solution, flavors, and nicotine level). Since the effects of E-cigs on the microvascular responses in skeletal muscle are poorly understood, we used intravital microscopy with an acute (one-time 10 puff) exposure paradigm to evaluate the individual components of e-liquid on vascular tone and endothelial function in the arterioles of the gluteus maximus muscle of anesthetized C57Bl/6 mice. Consistent with the molecular responses seen with endothelial cells, we found that the peripheral vasoconstriction response was similar between mice exposed to E-cig aerosol or cigarette smoke (i.e., 3R4F reference cigarette); this response was not nicotine dependent, and endothelial cell-mediated vasodilation was not altered within this acute exposure paradigm. We also report that, regardless of the base solution component [i.e., vegetable glycerin (VG)-only or propylene glycol (PG)-only], the vasoconstriction responses were the same in mice with inhalation exposure to 3R4F cigarette smoke or E-cig aerosol. Key findings from this work reveal that some component other than nicotine, in inhaled smoke or aerosol, is responsible for triggering peripheral vasoconstriction in skeletal muscle, and that regardless of one's preference for an E-cig base solution composition (i.e., ratio of VG-to-PG), the acute physiological response to blood vessels appears to be the same. The data suggest that vaping is not likely to be 'safer' than smoking towards blood vessels and can be expected to produce and/or result in the same adverse vascular health outcomes associated with smoking cigarettes.

Maternal electronic cigarette use during pregnancy affects long-term arterial function in offspring.

Vaping, or electronic cigarette (ecig) use, is prevalent among pregnant women, although little is known about the effects of perinatal ecig use on cardiovascular health of the progeny (even when using nicotine-free e-liquid). Maternal toxicant inhalation may adversely affect vital conduit vessel development. We tested the hypothesis that perinatal exposure to maternal vaping would lead to a dose-dependent dysfunction that would persist into later life of offspring. Pregnant Sprague-Dawley rats were exposed to either nicotine-free (ecig0) or nicotine-containing ecig aerosol (18 mg/mL, ecig18) starting on gestational day 2 and continued until pups were weaned (postnatal day 21). Pups were never directly exposed. Conduit artery function (stiffness and reactivity) and structure were assessed in 3- and 7-mo-old offspring. At 3 mo, pulse wave velocity (PWV) in the ecig0 and ecig18 offspring was significantly higher than controls in both the 20 puffs/day (6.6 ± 2.1 and 4.8 ± 1.3 vs. 3.2 ± 0.7 m/s, respectively, P < 0.05, means ± SD) and in 60 puffs/day exposure cohort (7.5 ± 2.8 and 7.5 ± 2.5 vs. 3.2 ± 0.5 m/s, respectively, P < 0.01). Wire myography revealed (range of 23%-31%) impaired aortic relaxation in all ecig exposure groups (with or without nicotine). Incubation of vessels with TEMPOL or Febuxostat reversed the aortic dysfunction, implicating the involvement of reactive oxygen species. Nearly identical changes and pattern was seen in vascular outcomes of 7-mo-old offspring. The take-home message from this preclinical study is that maternal vaping during pregnancy, with or without nicotine, leads to maladaptations in vascular (aortic) development that persist into adult life of offspring.NEW & NOTEWORTHY We observe a significant alteration in arterial structure and function in adolescent and adult offspring due to developmental exposure to toxicants resulting from perinatal maternal vaping. Taken together with previous work that described lasting dysfunction in cerebral microvasculature in offspring, these data underscore the adverse consequences of maternal exposure to electronic cigarette aerosol in conduit and resistance vessels alike, irrespective of nicotine content.

College Students' Perceptions About Prescription Drug Misuse Among Peers.

BACKGROUND: Prescription drug misuse is an escalating public health problem that is prevalent among college students. Various factors, such as sex, age, race, mental health conditions, and fraternity and sorority membership, increase the risk for prescription drug misuse. Peer influences may also pose significant risks for starting prescription drug misuse, because peers are the primary source of misused prescription drugs among college students. OBJECTIVES: To examine college students' beliefs about prescription drug misuse among their peers and to understand their beliefs about the available and potential intervention efforts to reduce prescription drug misuse. METHOD: We conducted a cross-sectional survey of 312 college students aged 18 to 30 years who were enrolled in a large midwestern US university. The survey included questions about the responders' demographic characteristics, beliefs, and perceptions regarding prescription drug misuse among their peers and potential reduction programs for prescription drug misuse. RESULTS: The respondents' mean age was 21 years, and most (65%) respondents were women. A majority (90%) of the respondents were enrolled in the university as full-time students. More than 60% of the respondents reported knowing someone with prescription drug misuse in the past 12 months. Fraternity or sorority members were more likely to report peer prescription drug misuse than nonmembers (83% vs 60%, respectively; P = .017). Stimulants were the most misused drug class, accounting for 75% of all reported peer prescription drug misuse. Approximately 60% of the misused prescription drugs were sourced from peers, which included friends, roommates, and classmates. A total of 73% of respondents said that prescription drug misuse was a problem among college students and 67% agreed that interventions were needed to reduce prescription drug misuse. The perceived need for interventions varied by peer prescription drug misuse. A total of 90% of students whose peers did not misuse prescription drugs said that interventions were needed, but only 67% of those with peer prescription drug misuse thought that interventions were needed. CONCLUSION: Our findings indicate that peer prescription drug misuse is very common among college students, and the most misused drug class is stimulants. Survey respondents perceived that the current interventions used to address prescription drug misuse are not very effective or may not be targeting the right population. Peer prescription drug misuse influences college students' perceptions about the risks and harms of prescription drug misuse, as well as the need for interventions.

Waterpipe tobacco smoking: what is the evidence that it supports nicotine/tobacco dependence?

OBJECTIVE: Waterpipe tobacco smoking (WTS) involves passing tobacco smoke through water prior to inhalation, and has spread worldwide. This spread becomes a public health concern if it is associated with tobacco-caused disease and if WTS supports tobacco/nicotine dependence. A growing literature demonstrates that WTS is associated with disability, disease and death. This narrative review examines if WTS supports nicotine/tobacco dependence, and is intended to help guide tobacco control efforts worldwide. DATA SOURCES: PUBMED search using: (("waterpipe" or "narghile" or "arghile" or "shisha" or "goza" or "narkeela" or "hookah" or "hubble bubble")) AND ("dependence" or "addiction"). STUDY SELECTION: Excluded were articles not in English, without original data, and that were not topic-related. Thirty-two articles were included with others identified by inspecting reference lists and other sources. DATA SYNTHESIS: WTS and the delivery of the dependence-producing drug nicotine were examined, and then the extent to which the articles addressed WTS-induced nicotine/dependence explicitly, as well as implicitly with reference to criteria for dependence outlined by the WHO. CONCLUSIONS: WTS supports nicotine/tobacco dependence because it is associated with nicotine delivery, and because some smokers experience withdrawal when they abstain from waterpipe, alter their behaviour in order to access a waterpipe and have difficulty quitting, even when motivated to do so. There is a strong need to support research investigating measurement of WTS-induced tobacco dependence, to inform the public of the risks of WTS, which include dependence, disability, disease and death, and to include WTS in the same public health policies that address tobacco cigarettes.