New study examines e-cigarette vapour effects on vascular barrier cells

A new open-access paper in Respiratory Research has examined how nicotine-containing e-cigarette vapour affected endothelial barrier function in laboratory models.

The study, published on 26 September, used human umbilical vein endothelial cells and an isolated ventilated mouse-lung model. The authors reported that nicotine-containing e-cigarette vapour extract increased angiopoietin-2 secretion and transcription in cells after 24 hours, and made the endothelial barrier more susceptible to lipopolysaccharide challenge in vitro. In the isolated mouse-lung model, intratracheal nicotine-containing vapour exposure was associated with increased endothelial permeability and oedema formation.

The paper also tested PMC-403, a synthetic Tie-2 agonist, in these models. The authors reported reduced barrier dysfunction in the experimental settings, framing the compound as a potential research route for acute lung injury contexts. That should not be read as consumer advice or as evidence that a treatment exists for harms from vaping.

How to read the finding

This is mechanistic research, not a study of real-world disease rates in adult vapers. It used cell and ex vivo animal-lung models, acute exposures and a specific experimental setup. It does not tell readers how a particular UK product, liquid, flavour or device will perform in everyday use.

For UK readers, the wider context remains nuanced. NHS advice says nicotine vaping is less harmful than smoking for adult smokers who switch completely, but also stresses that vaping is not risk-free and that children and non-smokers should never vape. The 2022 English evidence update likewise concluded that vaping carries a small fraction of the short- and medium-term risks of smoking, while highlighting uncertainty about long-term effects and the need for better evidence.

The useful takeaway is cautious rather than dramatic: the study adds to biological research on possible pathways of harm, but it does not overturn existing harm-reduction guidance for adult smokers considering a complete switch away from cigarettes.