The case of young people who use e-cigarettes infrequently: Who is this population? What becomes of them?

BACKGROUND: Emerging data indicate that many adolescents and young adults ("youth") engage in infrequent, or occasional, e-cigarette use. However, little is known about this population as they are often subsumed into the broader "any past-30-day use" category used to define youth "current use." This study aimed to focus on infrequent e-cigarette use by youth, examining its correlates and transitional outcomes. METHODS: Participants were from a prospective cohort study of youth (aged 15-24 at baseline). Among youth who had used e-cigarettes, we classified "infrequent use" as using e-cigarettes ≤5 days in the last 30 days (n=273) and "frequent use" as using e-cigarettes ≥6 days in the last 30 days (n=278). Descriptive statistics, Markov modeling, and logistic regression were utilized. RESULTS: By the 12-month follow-up, 76.8% of those using infrequently at baseline remained in the "infrequent use" category, 6.3% reported no recent use, and 16.8% had escalated to the "frequent use" category. Among the youth using infrequently at baseline, those who did (vs. did not) escalate to frequent use by follow-up had higher baseline nicotine dependence and were more likely to have family members who used tobacco. CONCLUSIONS: Infrequent e-cigarette use is extremely common, and often fairly stable, among young people. Prevention efforts must certainly attempt to reduce escalation and attend to both individual and interpersonal factors (e.g., nicotine dependence, family use). Yet prevention efforts must additionally attend to the case of continued infrequent use, given the high prevalence of people in this category and their regular exposure to e-cigarette harms.

Guidelines for in vivo models of developmental programming of cardiovascular disease risk.

Research using animals depends on the generation of offspring for use in experiments or for the maintenance of animal colonies. Although not considered by all, several different factors preceding and during pregnancy, as well as during lactation, can program various characteristics in the offspring. Here, we present the most common models of developmental programming of cardiovascular outcomes, important considerations for study design, and provide guidelines for producing and reporting rigorous and reproducible cardiovascular studies in offspring exposed to normal conditions or developmental insult. These guidelines provide considerations for the selection of the appropriate animal model and factors that should be reported to increase rigor and reproducibility while ensuring transparent reporting of methods and results.

Nicotine information disclosed online by e-cigarette brands popular with young people.

INTRODUCTION: E-cigarette use is most prevalent among adolescents and young adults - and there are often misperceptions about product risk. The purpose of this study was to determine what nicotine information is provided on e-cigarette brand websites. METHODS: Based on national and local surveys, we identified 44 e-cigarette brands commonly used in the US by adolescents and young adults. For each of these brands, their associated websites were analyzed for disclosed nicotine information. Specifically, for each brand's website, we coded whether there was information on nicotine concentration (recorded if a numerical value was provided such as '5% nicotine'), nicotine form (free-base, nicotine salts, or not stated), and nicotine type (tobacco-derived, synthetically derived, or not stated). Coding allowed for both lay (e.g. 'nic salts') as well as scientific (e.g. 'isomers') terms. RESULTS: Of the 44 brands examined, all provided basic information on nicotine concentration (e.g. '5% nicotine'). However, 23% of brands did not disclose information on nicotine form (i.e. nicotine salt vs free-base), and 66% of brands did not disclose information on nicotine type (i.e. synthetic vs tobacco-derived). CONCLUSIONS: Overall, these results suggest that the e-cigarette industry is not fully informing its consumers about the nicotine in their products. Given that nicotine form and type have implications for e-cigarette addiction potential, these findings highlight a public health concern. There is a need for more comprehensive national regulations for mandating product constituents and emissions disclosures.

Maternal exercise preserves offspring cardiovascular health via oxidative regulation of the ryanodine receptor.

OBJECTIVE: The intrauterine environment during pregnancy is a critical factor in the development of obesity, diabetes, and cardiovascular disease in offspring. Maternal exercise prevents the detrimental effects of a maternal high fat diet on the metabolic health in adult offspring, but the effects of maternal exercise on offspring cardiovascular health have not been thoroughly investigated. METHODS: To determine the effects of maternal exercise on offspring cardiovascular health, female mice were fed a chow (C; 21% kcal from fat) or high-fat (H; 60% kcal from fat) diet and further subdivided into sedentary (CS, HS) or wheel exercised (CW, HW) prior to pregnancy and throughout gestation. Offspring were maintained in a sedentary state and chow-fed throughout 52 weeks of age and subjected to serial echocardiography and cardiomyocyte isolation for functional and mechanistic studies. RESULTS: High-fat fed sedentary dams (HS) produced female offspring with reduced ejection fraction (EF) compared to offspring from chow-fed dams (CS), but EF was preserved in offspring from high-fat fed exercised dams (HW) throughout 52 weeks of age. Cardiomyocytes from HW female offspring had increased kinetics, calcium cycling, and respiration compared to CS and HS offspring. HS offspring had increased oxidation of the RyR2 in cardiomyocytes coupled with increased baseline sarcomere length, resulting in RyR2 overactivity, which was negated in female HW offspring. CONCLUSIONS: These data suggest a role for maternal exercise to protect against the detrimental effects of a maternal high-fat diet on female offspring cardiac health. Maternal exercise improved female offspring cardiomyocyte contraction, calcium cycling, respiration, RyR2 oxidation, and RyR2 activity. These data present an important, translatable role for maternal exercise to preserve cardiac health of female offspring and provide insight on mechanisms to prevent the transmission of cardiovascular diseases to subsequent generations.

Demographic and Behavioral Differences Between Adolescents and Young Adults Who Use E-Cigarettes at Low and High Frequency.

BACKGROUND: Among adolescents and young adults (AYAs), "current use" of electronic cigarettes (e-cigarettes) is commonly defined as any use in the past 30 days. However, few studies have examined differences among those within this broad category. This study examined characteristics of AYAs who used e-cigarettes at a low frequency (within the last 3 months but <6 days out of the past 30 days) and those who used e-cigarettes at a high frequency (6+ days out of the past 30 days). METHODS: We conducted cross-sectional analyses among 551 Ohio AYAs (15- to 24-year-olds) who reported using an e-cigarette to vape nicotine in the past 3 months. We used descriptive statistics and logistic regression to characterize those using e-cigarettes at a low frequency and a high frequency. RESULTS: Among our sample of AYAs who reported past 3-month e-cigarette use, about half (50.8%) reported using an e-cigarette 6 or more days out of the past 30 days (ie, high frequency). In the multivariable analysis, reported nicotine dependence (Odds Ratio [OR]: 7.0, 95% CI: 4.8, 10.3) and current other tobacco product use (OR: 1.8, 95% CI: 1.1, 2.9) were associated with high-frequency e-cigarette use. CONCLUSION: Our results suggest that frequency of use is an important characteristic in understanding AYA e-cigarette use. Any use in the past 30 days may not be sensitive enough to understand dependence and tobacco-use behaviors. Further characterizing "current" e-cigarette use by frequency of use may provide meaningful information for public health professionals to better target intervention and cessation efforts to AYAs.

MicroRNA-1 Deficiency Is a Primary Etiological Factor Disrupting Cardiac Contractility and Electrophysiological Homeostasis.

BACKGROUND: MicroRNA-1 (miR1), encoded by the genes miR1-1 and miR1-2, is the most abundant microRNA in the heart and plays a critical role in heart development and physiology. Dysregulation of miR1 has been associated with various heart diseases, where a significant reduction (>75%) in miR1 expression has been observed in patient hearts with atrial fibrillation or acute myocardial infarction. However, it remains uncertain whether miR1-deficiency acts as a primary etiological factor of cardiac remodeling. METHODS: miR1-1 or miR1-2 knockout mice were crossbred to produce 75%-miR1-knockdown (75%KD; miR1-1+/-:miR1-2-/- or miR1-1-/-:miR1-2+/-) mice. Cardiac pathology of 75%KD cardiomyocytes/hearts was investigated by ECG, patch clamping, optical mapping, transcriptomic, and proteomic assays. RESULTS: In adult 75%KD hearts, the overall miR1 expression was reduced to ≈25% of the normal wild-type level. These adult 75%KD hearts displayed decreased ejection fraction and fractional shortening, prolonged QRS and QT intervals, and high susceptibility to arrhythmias. Adult 75%KD cardiomyocytes exhibited prolonged action potentials with impaired repolarization and excitation-contraction coupling. Comparatively, 75%KD cardiomyocytes showcased reduced Na+ current and transient outward potassium current, coupled with elevated L-type Ca2+ current, as opposed to wild-type cells. RNA sequencing and proteomics assays indicated negative regulation of cardiac muscle contraction and ion channel activities, along with a positive enrichment of smooth muscle contraction genes in 75%KD cardiomyocytes/hearts. miR1 deficiency led to dysregulation of a wide gene network, with miR1's RNA interference-direct targets influencing many indirectly regulated genes. Furthermore, after 6 weeks of bi-weekly intravenous tail-vein injection of miR1 mimics, the ejection fraction and fractional shortening of 75%KD hearts showed significant improvement but remained susceptible to arrhythmias. CONCLUSIONS: miR1 deficiency acts as a primary etiological factor in inducing cardiac remodeling via disrupting heart regulatory homeostasis. Achieving stable and appropriate microRNA expression levels in the heart is critical for effective microRNA-based therapy in cardiovascular diseases.

What do young people know about the nicotine in their e-cigarettes?

INTRODUCTION: In recent years, the nicotine in e-cigarettes has been available in either a 'free-base' (unprotonated) or 'nicotine salt' (protonated) form. Additionally, e-cigarette nicotine can be either 'synthetic' or 'tobacco-derived'. These dimensions of nicotine have implications for nicotine absorption, bioavailability and sensory experiences. However, it is unclear if the young people using e-cigarettes are aware of these nicotine dimensions. METHODS: Data came from a cohort of Ohio youth (aged 15-24) who reported using an e-cigarette in the past 4 months (N=271). Participants were enrolled and provided background information in 2021; their 12-month follow-up survey asked about the presence, form and type of nicotine in their usual e-cigarette. Individuals who reported that they could distinguish between tobacco-derived and synthetic nicotine were additionally asked to describe the difference. RESULTS: Of the 247 youth who reported that there was nicotine in their usual e-cigarette, 71.7% did not know whether it was free-base or nicotine salt and 75.7% did not know whether it was synthetic or tobacco-derived. Awareness was higher among youth who were using e-cigarettes at a greater frequency and quantity. The majority reported that they could not detect a difference between the experience of using synthetic vs tobacco-derived nicotine. CONCLUSIONS: These findings indicate the generally limited awareness about nicotine among youth who used e-cigarettes. Improvements in health communications and requirements for e-cigarette industry disclosures are necessary to ensure that consumers are better informed about the dimensions-and the risks-of the nicotine they are consuming.

Sex-specific lung inflammation and mitochondrial damage in a model of electronic cigarette exposure in asthma.

The prevalence of electronic cigarette (EC) use among adult with asthma has continued to increase over time, in part due to the belief of being less harmful than smoking. However, the extent of their toxicity and the involved mechanisms contributing to the deleterious impact of EC exposure on patients with preexisting asthma have not been delineated. In the present project, we tested the hypothesis that EC use contributes to respiratory damage and worsening inflammation in the lungs of patients with asthma. To define the consequences of EC exposure in established asthma, we used a mouse model with/without preexisting asthma for short-term exposure to EC aerosols. C57/BL6J mice were sensitized and challenged with a DRA (dust mite, ragweed, Aspergillus fumigates, 200 µg/mL) mixture and exposed daily to EC with nicotine (2% nicotine in 30:70 propylene glycol: vegetable glycerin) or filtered air for 2 wk. The mice were evaluated at 24 h after the final EC exposure. After EC exposure in asthmatic mice, lung inflammatory cell infiltration and goblet cell hyperplasia were increased, whereas EC alone did not cause airway inflammation. Our data also show that mitochondrial DNA (mtDNA) content and a key mtDNA regulator, mitochondrial transcription factor A (TFAM), are reduced in asthmatic EC-exposed mice in a sex-dependent manner. Together, these results indicate that TFAM loss in lung epithelium following EC contributes to male-predominant sex pathological differences, including mitochondrial damage, inflammation, and remodeling in asthmatic airways.NEW & NOTEWORTHY Respiratory immunity is dysregulated in preexisting asthma, and further perturbations by EC use could exacerbate asthma severity. However, the extent of their toxicity and the involved mechanisms contributing to the deleterious impact of EC exposure on patients with preexisting asthma have not been delineated. We found that EC has unique biological impacts in lungs and potential sex differences with loss of TFAM, a key mtDNA regulator, in lung epithelial region from our animal EC study.

E-cigarettes and arrhythmogenesis: a comprehensive review of pre-clinical studies and their clinical implications.

Electronic cigarette use has grown exponentially in recent years, and while their popularity has increased, the long-term effects on the heart are yet to be fully studied and understood. Originally designed as devices to assist with those trying to quit traditional combustible cigarette use, their popularity has attracted use by teens and adolescents who traditionally have not smoked combustible cigarettes. Acute effects on the heart have been shown to be similar to traditional combustible cigarettes, including increased heart rate and blood pressure. The main components of electronic cigarettes that contribute to these arrhythmic effects are found in the e-liquid that is aerosolized and inhaled, comprised of nicotine, flavourings, and a combination of vegetable glycerin (VG) and propylene glycol (PG). Nicotine can potentially induce both ventricular and atrial arrhythmogenesis, with both the atrial and ventricular effects resulting from the interactions of nicotine and the catecholamines they release via potassium channels. Atrial arrhythmogenesis, more specifically atrial fibrillation, can also occur due to structural alterations, which happens because of nicotine downregulating microRNAs 133 and 590, both post-transcriptional growth factor repressors. Liquid flavourings and the combination of PG and VG can possibly lead to arrhythmic events by exposing users to acrolein, an aldehyde that stimulates TRPA1 that in turn causes a change towards sympathetic activation and autonomic imbalance. The design of these electronic delivery devices is constantly changing; therefore, it has proven extremely difficult to study the long-term effects on the heart caused by electronic cigarettes but will be important to understand given their rising popularity. The arrhythmic effects of electronic cigarettes appear similar to traditional cigarettes as well; however, a comprehensive review has not been compiled and is the focus of this article.

Enhancing Partnerships of Institutions and Journals to Address Concerns About Research Misconduct: Recommendations From a Working Group of Institutional Research Integrity Officers and Journal Editors and Publishers.

Importance: Institutions and journals strive to promote and protect the integrity of the research record, and both groups are equally committed to ensuring the reliability of all published data. Observations: Three US universities coordinated a series of virtual meetings from June 2021 to March 2022 for a working group composed of senior, experienced US research integrity officers (RIOs), journal editors, and publishing staff who are familiar with managing issues of research integrity and publication ethics. The goal of the working group was to improve the collaboration and transparency between institutions and journals to ensure that research misconduct and publication ethics are managed properly and efficiently. Recommendations address the following: identifying proper contacts at institutions and journals, specifying information to share between institutions and journals, correcting the research record, reconsideration of some fundamental research misconduct concepts, and journal policy changes. The working group identified 3 key recommendations to be adopted and implemented to change the status quo for better collaboration between institutions and journals: (1) reconsideration and broadening of the interpretation by institutions of the need-to-know criteria in federal regulations (ie, confidential or sensitive information and data are not disclosed unless there is a need for an individual to know the facts to perform specific jobs or functions), (2) uncoupling the evaluation of the accuracy and validity of research data from the determination of culpability and intent of the individuals involved, and (3) initiating a widespread change for the policies of journals and publishers regarding the timing and appropriateness for contacting institutions, either before or concurrently under certain conditions, when contacting the authors. Conclusions and Relevance: The working group recommends specific changes to the status quo to enable effective communication between institutions and journals. Using confidentiality clauses and agreements to impede sharing does not benefit the scientific community nor the integrity of the research record. However, a careful and informed framework for improving communications and sharing information between institutions and journals can foster better working relationships, trust, transparency, and most importantly, faster resolution to data integrity issues, especially in published literature.

Long-Term Impact of Daily E-cigarette Exposure on the Lungs of Asthmatic Mice.

INTRODUCTION: Although the greater popularity of electronic cigarettes (EC) among asthmatics is alarming, there is limited knowledge of the long-term consequences of EC exposure in asthmatics. AIMS AND METHODS: Mild asthmatic C57/BL6J adult male and female mice were established by intranasal insufflation with three combined allergens. The asthmatic and age and sex-matched' naïve mice were exposed to air, nicotine-free (propylene glycol [PG]/vegetable glycerin [VG]-only), or PG/VG+Nicotine, 4 hours daily for 3 months. The effects of EC exposure were accessed by measuring cytokines in bronchoalveolar lavage, periodic acid-schiff (PAS) staining, mitochondrial DNA copy numbers (mtCN), and the transcriptome in the lung. Significance was false discovery rate <0.2 for transcriptome and 0.05 for the others. RESULTS: In asthmatic mice, PG/VG+Nicotine increased PAS-positive cells and IL-13 compared to mice exposed to air and PG/VG-only. In naïve mice exposed to PG/VG+Nicotine and PG/VG-only, higher INF-γ was observed compared to mice exposed only to air. PG/VG-only and PG/VG+Nicotine had significantly higher mtCN compared to air exposure in asthmatic mice, while the opposite pattern was observed in non-asthmatic naïve mice. Different gene expression patterns were profoundly found for asthmatic mice exposed to PG/VG+Nicotine compared to PG/VG-only, including genes involved in mitochondrial dysfunction, oxidative phosphorylation, and p21-activated kinase (PAK) signaling. CONCLUSIONS: This study provides experimental evidence of the potential impact of nicotine enhancement on the long-term effects of EC in asthmatics compared to non-asthmatics. IMPLICATIONS: The findings from this study indicate the potential impact of EC in asthmatics by addressing multiple biological markers. The long-term health outcomes of EC in the susceptible group can be instrumental in supporting policymaking and educational campaigns and informing the public, healthcare providers, and EC users about the underlying risks of EC use.

Electronic Nicotine Delivery Systems and Cardiovascular/Cardiometabolic Health.

The use of electronic nicotine delivery systems, specifically electronic cigarettes (e-cig), has risen dramatically within the last few years; the demographic purchasing these devices is now predominantly adolescents that are not trying to quit the use of traditional combustible cigarettes, but rather are new users. The composition and appearance of these devices has changed since their first entry into the market in the late 2000s, but they remain composed of a battery and aerosol delivery system that is used to deliver breakdown products of propylene glycol/vegetable glycerin, flavorings, and potentially nicotine or other additives. Manufacturers have also adjusted the type of nicotine that is used within the liquid to make the inhalation more palatable for younger users, further affecting the number of youth who use these devices. Although the full spectrum of cardiovascular and cardiometabolic consequences of e-cig use is not fully appreciated, data is beginning to show that e-cigs can cause both short- and long-term issues on cardiac function, vascular integrity and cardiometabolic issues. This review will provide an overview of the cardiovascular, cardiometabolic, and vascular implications of the use of e-cigs, and the potential short- and long-term health effects. A robust understanding of these effects is important in order to inform policy makers on the dangers of e-cigs use.

Engineered Extracellular Vesicles Derived from Dermal Fibroblasts Attenuate Inflammation in a Murine Model of Acute Lung Injury.

Acute respiratory distress syndrome (ARDS) represents a significant burden to the healthcare system, with ≈200 000 cases diagnosed annually in the USA. ARDS patients suffer from severe refractory hypoxemia, alveolar-capillary barrier dysfunction, impaired surfactant function, and abnormal upregulation of inflammatory pathways that lead to intensive care unit admission, prolonged hospitalization, and increased disability-adjusted life years. Currently, there is no cure or FDA-approved therapy for ARDS. This work describes the implementation of engineered extracellular vesicle (eEV)-based nanocarriers for targeted nonviral delivery of anti-inflammatory payloads to the inflamed/injured lung. The results show the ability of surfactant protein A (SPA)-functionalized IL-4- and IL-10-loaded eEVs to promote intrapulmonary retention and reduce inflammation, both in vitro and in vivo. Significant attenuation is observed in tissue damage, proinflammatory cytokine secretion, macrophage activation, influx of protein-rich fluid, and neutrophil infiltration into the alveolar space as early as 6 h post-eEVs treatment. Additionally, metabolomics analyses show that eEV treatment causes significant changes in the metabolic profile of inflamed lungs, driving the secretion of key anti-inflammatory metabolites. Altogether, these results establish the potential of eEVs derived from dermal fibroblasts to reduce inflammation, tissue damage, and the prevalence/progression of injury during ARDS via nonviral delivery of anti-inflammatory genes/transcripts.

In Utero Exposure to Maternal Electronic Nicotine Delivery System use Demonstrate Alterations to Craniofacial Development.

OBJECTIVE: Develop a model for the study of Electronic Nicotine Device (ENDS) exposure on craniofacial development. DESIGN: Experimental preclinical design followed as pregnant murine dams were randomized and exposed to filtered air exposure, carrier exposure consisting of 50% volume of propylene glycol and vegetable glycine (ENDS Carrier) respectively, or carrier exposure with 20 mg/ml of nicotine added to the liquid vaporizer (ENDS carrier with nicotine). SETTING: Preclinical murine model exposure using the SciReq exposure system. PARTICIPANTS: C57BL6 adult 8 week old female pregnant mice and exposed in utero litters. INTERVENTIONS: Exposure to control filtered air, ENDS carrier or ENDS carrier with nicotine added throughout gestation at 1 puff/minute, 4 h/day, five days a week. MAIN OUTCOME MEASURES: Cephalometric measures of post-natal day 15 pups born as exposed litters. RESULTS: Data suggests alterations to several facial morphology parameters in the developing offspring, suggesting electronic nicotine device systems may alter facial growth if used during pregnancy. CONCLUSIONS: Future research should concentrate on varied formulations and exposure regimens of ENDS to determine timing windows of exposures and ENDS formulations that may be harmful to craniofacial development.

E-cigarette vapor exposure in utero causes long-term pulmonary effects in offspring.

The in utero environment is sensitive to toxicant exposure, altering the health and growth of the fetus, and thus sensitive to contaminant exposure. Though recent clinical data suggest that e-cigarette use does no further harm to birth outcomes than a nicotine patch, this does not account for the effects of vaping during pregnancy on the long-term health of offspring. Pregnant mice were exposed to: 1) e-cigarette vapor with nicotine (PV + Nic; 2% Nic in 50:50 propylene glycol: vegetable glycerin), 2) e-cigarette vapor without nicotine [PV; (50:50 propylene glycol:vegetable glycerin)], or 3) HEPA filtered air (FA). Dams were removed from exposure upon giving birth. At 5 mo of age, pulmonary function tests on the offspring revealed female and male mice from the PV group had greater lung stiffness (Ers) and alveolar stiffness (H) compared with the FA group. Furthermore, baseline compliance (Crs) was reduced in female mice from the PV group and in male mice from the PV and PV + Nic groups. Lastly, female mice had decreased forced expiratory volume (FEV0.1) in the PV group, but not in the male groups, compared with the FA group. Lung histology revealed increased collagen deposition around the vessels/airways and in alveolar tissue in PV and PV + Nic groups. Furthermore, goblet hyperplasia was observed in PV male and PV/PV + Nic female mice. Our work shows that in utero exposure to e-cigarette vapor, regardless of nicotine presence, causes lung dysfunction and structural impairments that persist in the offspring to adulthood.

CLIC4 localizes to mitochondrial-associated membranes and mediates cardioprotection.

Mitochondrial-associated membranes (MAMs) are known to modulate organellar and cellular functions and can subsequently affect pathophysiology including myocardial ischemia-reperfusion (IR) injury. Thus, identifying molecular targets in MAMs that regulate the outcome of IR injury will hold a key to efficient therapeutics. Here, we found chloride intracellular channel protein (CLIC4) presence in MAMs of cardiomyocytes and demonstrate its role in modulating ER and mitochondrial calcium homeostasis under physiological and pathological conditions. In a murine model, loss of CLIC4 increased myocardial infarction and substantially reduced cardiac function after IR injury. CLIC4 null cardiomyocytes showed increased apoptosis and mitochondrial dysfunction upon hypoxia-reoxygenation injury in comparison to wild-type cardiomyocytes. Overall, our results indicate that MAM-CLIC4 is a key mediator of cellular response to IR injury and therefore may have a potential implication on other pathophysiological processes.