a mouse model for chronic intermittent electronic cigarette exposure exhibits nicotine pharmacokinetics resembling human vapers.

Introduction:
This text describes a study conducted to develop a mouse model for chronic intermittent electronic cigarette (E-cig) exposure that exhibits nicotine pharmacokinetics resembling human vapers. The study aimed to establish an E-cig aerosol generation and exposure system for rodents and a chronic intermittent delivery method that simulates E-cig users who vape episodically during wakefulness and abstain during sleep. The researchers assessed the body weight, food intake, and locomotor activity of apolipoprotein E null (apoE-/-) mice exposed to chronic intermittent E-cig aerosol. The study's key points and main message are summarized below.

Key Points:

* The study developed an E-cig aerosol generation and exposure system for rodents and a chronic intermittent delivery method.
* Mice were exposed to E-cig aerosol in a programmed schedule at various doses defined by the duration of each puff, number of puffs per delivery episode, and frequency of episodes in the dark phase of a 12/12-h circadian cycle for 9 consecutive days.
* Plasma nicotine and cotinine levels were positively correlated with exposure doses and showed a circadian variation.
* Chronic E-cig exposure to apoE-/- mice decreased body weight, food intake, and increased locomotion.
* The methodologies are essential tools for in vivo studies of the health impacts of E-cig exposure on the CNS, cardiovascular, pulmonary, hepatic systems, metabolism, and carcinogenesis.

Main Message:
The study successfully developed an E-cig aerosol generation and exposure system and a chronic intermittent delivery method that yield clinically relevant nicotine pharmacokinetics associated with behavioral and metabolic changes in mice. The methodologies can serve as essential tools for in vivo studies of the health impacts of E-cig exposure on various systems and diseases. The study highlights the importance of developing relevant animal models to study the health effects of E-cig exposure and the potential impact on public health.

Shao XM, Lopez B, Nathan D, et al. a mouse model for chronic intermittent electronic cigarette exposure exhibits nicotine pharmacokinetics resembling human vapers. Journal of neuroscience methods. 2019;326:108376. doi:10.1016/j.jneumeth.2019.108376