Heated tobacco products — Lower toxicity than combustible cigarettes but induce cell aging

A research group including Vice-president Akihito Ishigami at the Tokyo Metropolitan Institute for Geriatrics and Gerontology, along with Associate Professor Ayami Sato and Graduate Student Satsuki Kasahara at Toyo University, has announced that aerosols from heated tobacco products affect the expression of aging-related genes in lung fibroblasts differently than combustible cigarettes. These findings are expected to contribute to the evaluation of health risks associated with heated tobacco. The results were published in Geriatrics & Gerontology International on March 8.

In recent years, heated tobacco products, which generate an aerosol by heating tobacco leaves without burning them, have become widely popular, yet their effects on the human body have not been fully understood.

To address this, the research team focused on "cell aging," which is linked to the development of respiratory diseases, and investigated how heated tobacco aerosol components influence the expression of genes related to cell aging.

The effects of exposure to heated tobacco aerosol extracts and combusted tobacco smoke extracts were analyzed using fibroblasts derived from human lungs. The results confirmed that heated tobacco aerosol is less cytotoxic than combustible cigarette smoke.

On the other hand, repeated exposure to heated tobacco aerosol prepared at a high concentration (10-fold) increased the expression of genes involved in cellular senescence (CDKN2A, IL1B, MMP1, etc.) as in combustible cigarettes. These changes resembled the patterns found in models of replicative aging and drug-induced aging.

Additionally, while some changes in gene expression were common to both heated and combustible tobacco, other changes were unique to heated tobacco.

The study also revealed that repeated exposure to heated tobacco aerosols causes more significant changes in gene expression than a single exposure, a trend also observed with combustible cigarettes.

Ishigami stated: "Heated tobacco has been considered less toxic than conventional cigarettes, but this study suggests an impact on gene expression related to cellular senescence. We believe it is important to accumulate long-term, molecular-level studies to assess health effects."

Journal Information
Publication: Geriatrics & Gerontology International
Title: Effects of Aerosol Extract From Heated Tobacco Products on Senescence-Associated Gene Expression in Human Lung Fibroblasts
DOI: 10.1111/ggi.70436