Vaping additives cannabinoid oil and vitamin E acetate adhere to and damage the human airway epithelium

Summary & key facts

Researchers put human airway cells grown in the lab under e-cigarette aerosols that contained cannabinoid oil from cannabis (CBD oil), vitamin E acetate, or the common e-liquid base ingredients. After three days, CBD oil caused lots more airway cells to die, and CBD plus vitamin E acetate caused even more cell death. The team also saw the oils sticking to the airway surface and building up inside cells, and they measured protein changes that match cell stress and injury. These results help explain how vaping cannabis oils and vitamin E acetate might damage the airways, but this was a lab study on cells and not a direct test in people.

Key facts:

• The study used human bronchial airway cells grown in the lab and exposed them to e-cigarette aerosols that included CBD oil, vitamin E acetate, or the common e-liquid base propylene glycol and vegetable glycerin with and without nicotine.
• After three days of exposure, CBD oil caused a large increase in cell death compared with the common e-liquid base, and the combination of CBD oil plus vitamin E acetate caused even more cell death.
• Microscope images showed cannabinoid oil and vitamin E acetate stuck to the surface of the airway cells and cannabinoid material built up inside some cells before those cells died.
• Protein analysis of the fluid from the cell cultures showed increases in enzymes that handle foreign chemicals, signs of oxidative stress, and markers linked to cell damage and death.
• The authors suggest that sticky deposits from CBD oil and the uptake of both CBD oil and vitamin E acetate into cells raise metabolic stress, which likely contributes to higher cell death in airway epithelium.
• Because this work was done on cells in the lab, it shows a possible way vaping cannabis oil and vitamin E acetate can harm airway tissue, but it does not prove the same effects occur in people under all real-world vaping conditions.

Abstract

E-cigarette, or vaping product use-associated lung injury (EVALI), is a severe respiratory disorder that caused a sudden outbreak of hospitalized young people in 2019. Using cannabis oil containing vaping products, including vitamin E acetate contaminants, was found to be strongly associated with EVALI. However, the underlying tissue impacts of the condition are still largely unknown. Here, we focused on the vehicle cannabinoid oil (CBD oil) and contaminant vitamin E acetate (VEA) effects on airway epithelial cells. Primary human bronchial epithelial (HBE) cultures were exposed to e-liquid aerosols that contained CBD oil and VEA in combination or the common e-liquid components PG/VG with and without nicotine. Cell viability analysis indicated dramatically increased cell death counts after 3 days of CBD exposure, and this effect was even higher after CBD + VEA exposure. Microscopic examination of the cultures revealed cannabinoid and VEA depositions on the epithelial surfaces and cannabinoid accumulation in exposed cells, followed by cell death. These observations were supported by proteomic analysis of the cell secretions that exhibited increases in known markers of airway epithelial toxicity, such as xenobiotic enzymes, factors related to oxidative stress response, and cell death indicators. Overall, our study provides insights into the association between cannabinoid oil and vitamin E acetate vaping and lung injury. Collectively, our results suggest that the adherent accumulation of CBD oil on airway surfaces and the cellular uptake of both CBD oil- and VEA-containing condensates cause elevated metabolic stress, leading to increased cell death rates in human airway epithelial cultures.

Topics

Chronic Obstructive Pulmonary Disease (COPD) Research Neuroscience of respiration and sleep Respiratory and Cough-Related Research

Categories

Endocrine and Autonomic Systems Life Sciences Neuroscience

Tags

Airway Anesthesia Chemistry Epithelium Medicine Pathology Pharmacology Respiratory epithelium

Substances

Cannabis