Summary
Introduction:
This article, "Evaluation of secondary electronic cigarette inhalation on lipid metabolism in C57BL/6J mice using indirect calorimetry" published in Metabolism Open, investigates the impact of electronic cigarette (e-cigarette) inhalation on the metabolism of C57BL/6J mice. The study used indirect calorimetry to measure the respiratory exchange ratio (RER) to determine the shift in metabolism from carbohydrate to lipid metabolism in mice exposed to e-cigarette vapor. The study also assessed the effect of e-cigarette inhalation on blood glucose levels.
Key Points:
* The study used C57BL/6J mice, a strain known for its unique longevity and susceptibility to metabolic dysfunction, making it ideal for examining metabolic dynamics.
* Mice were exposed to room air (control) or e-cigarette vapor for 15 minutes in a 1L chamber over four consecutive days.
* The study measured the RER, which is the ratio of CO2 produced to O2 consumed per minute, to determine the predominant metabolic pathway. a lower RER indicates lipid metabolism, while a higher RER indicates carbohydrate metabolism.
* The study found that e-cigarette inhalation reduces the RER, indicating a shift towards lipid metabolism.
* The magnitude of the effect was influenced by gender, age, and time of day.
* The study also found that blood glucose concentrations were higher after e-cigarette inhalation compared with controls, but this difference was not significant.
* The study used binary logistic regression and Random Forests to evaluate the effect of independent variables on the treatment (control or e-cigarette) group.
Main Message:
The study suggests that e-cigarette inhalation promotes lipid metabolism, and the magnitude of the effect is influenced by gender, age, and time of day. The finding that e-cigarette inhalation reduces the RER, indicating a shift towards lipid metabolism, is consistent with the shift to lipid metabolism that is predicted with cigarette use. The study also found that blood glucose concentrations were higher after e-cigarette inhalation compared with controls, although this difference was not significant. These findings suggest that e-cigarette use may have metabolic consequences, and more long-term studies are needed to inform future policies regarding the potential health risks from e-cigarette use and how changes manifest over time. The study's findings are significant as they contribute to the growing body of evidence that e-cigarette use may have negative health consequences and highlight the need for further research in this area.
Citation
Crawford DL, Phillips aR, Williams TR. Evaluation of secondary electronic cigarette inhalation on lipid metabolism in C57BL/6J mice using indirect calorimetry. Metabolism open. 2021;12:100150. doi:10.1016/j.metop.2021.100150
