Dual use of e-cigarettes and combustible cigarettes elevates salivary DKK1 levels similar to exclusive smoking.
5 affiliations
- 1Pneumogenomics Laboratory, Instituto Nacional de Enfermedades Respiratorias Ismael Cosío Villegas, Mexico City, Mexico.
- 2Laboratorio de Inmunología Integrativa, Instituto Nacional de Enfermedades Respiratorias Ismael Cosío Villegas, Mexico City, Mexico.
- 3Facultad de Medicina, Unidad de Medicina Experimental, Universidad Nacional Autónoma de México, Mexico City, Mexico.
- 4Médica Sur Clinic & Foundation, Mexico City, Mexico.
- 5Escuela Militar de Medicina, Universidad del Ejército y Fuerza Aérea, Mexico City, Mexico.
Abstract
Background
Animal models and in vitro studies have demonstrated that the use of electronic cigarettes causes inflammation, oxidative stress, and cell death. This study aimed to quantify molecules associated with cell death in the saliva of dual electronic cigarette users and to compare these levels with those observed in users of combustible cigarettes.Methodology
We included three groups: (1) e-cigarette users who additionally smoke combustible cigarettes, "dual users" (DU users, n = 56), combustible cigarette smokers (CCS, n = 23), and non-smokers (NS, n = 40). We evaluated 10 molecules using a multiplex assay.Results
Dual users of e-cigarettes showed elevated cotinine levels and higher scores on the Fagerström Test for Nicotine Dependence (FTND), indicating greater nicotine dependence compared to combustible cigarette smokers. The dual-user group had significantly higher levels of Dickkopf-1 (DKK1) than the non-smoker group (220.6 pg./mL vs. 0, p = 0.030). Positive correlations were identified between DKK1 and 70-kilodalton heat shock protein (HSP70) (rho = 0.298, p = 0.042). A negative correlation was also found between HSP70 and the age of vaping initiation (rho = -0.289, p = 0.043), and a positive correlation with the duration of vaping sessions (rho = 0.292, p = 0.042), indicating that starting vaping at a young age and prolonging sessions may increase the expression of this protein.Conclusion
Dual users of electronic cigarettes exhibit elevated salivary DKK1 levels and significant correlations with HSP70; these results suggest that chronic use may alter the inflammatory process. The pattern of e-cigarette consumption and the age of initiation modify salivary HSP70 levels. These proteins are involved in cellular stress and inflammatory mechanisms.
Related
- Scientific assessment of oral nicotine pouches and associated risk reduction in comparison to combustible cigarettes
- International best practice in the cessation of vaping and non-combustible nicotine use, and barriers, facilitators and treatment preferences: A rapid review
- Comparative HPHC Emission Profiles of Combustible and Alternative Nicotine Products in South Africa: Development of a Relative HPHC Emission Index
- Estimating price and expenditure elasticities of demand for cigarettes, beer and soda in Uganda: evidence from eight waves of the Uganda National Panel Survey using the Deaton approach
- CD38 inhibition increases neuronal survival and reduces α-synuclein in vitro, elevates brain NAD+, and reduces motor deficits in a Parkinson’s disease model
BibTeX
@article{vazquezlopez2026dual,
title = {{Dual use of e-cigarettes and combustible cigarettes elevates salivary DKK1 levels similar to exclusive smoking.}},
author = {Nayeli Itzel Vázquez-López and Ramcés Falfán-Valencia and Leslie Chavez-Galan and Ingrid Fricke-Galindo and Espiridión Ramos-Martínez and Raúl Sansores and Alejandra Ramirez Venegas and Cristina Rivera-González and Gloria Pérez-Rubio},
journal = {Frontiers in public health},
year = {2026},
month = oct,
doi = {10.3389/fpubh.2026.1951458},
url = {https://europepmc.org/article/MED/42903173},
note = {CC BY},
}
RIS
TY - JOUR
TI - Dual use of e-cigarettes and combustible cigarettes elevates salivary DKK1 levels similar to exclusive smoking.
AU - Nayeli Itzel Vázquez-López
AU - Ramcés Falfán-Valencia
AU - Leslie Chavez-Galan
AU - Ingrid Fricke-Galindo
AU - Espiridión Ramos-Martínez
AU - Raúl Sansores
AU - Alejandra Ramirez Venegas
AU - Cristina Rivera-González
AU - Gloria Pérez-Rubio
PY - 2026
DA - 2026/10/06
JO - Frontiers in public health
DO - 10.3389/fpubh.2026.1951458
UR - https://europepmc.org/article/MED/42903173
AB - Background Animal models and in vitro studies have demonstrated that the use of electronic cigarettes causes inflammation, oxidative stress, and cell death. This study aimed to quantify molecules associated with cell death in the saliva of dual electronic cigarette users and to compare these levels with those observed in users of combustible cigarettes.Methodology We included three groups: (1) e-cigarette users who additionally smoke combustible cigarettes, "dual users" (DU users, n = 56), combustible cigarette smokers (CCS, n = 23), and non-smokers (NS, n = 40). We evaluated 10 molecules using a multiplex assay.Results Dual users of e-cigarettes showed elevated cotinine levels and higher scores on the Fagerström Test for Nicotine Dependence (FTND), indicating greater nicotine dependence compared to combustible cigarette smokers. The dual-user group had significantly higher levels of Dickkopf-1 (DKK1) than the non-smoker group (220.6 pg./mL vs. 0, p = 0.030). Positive correlations were identified between DKK1 and 70-kilodalton heat shock protein (HSP70) (rho = 0.298, p = 0.042). A negative correlation was also found between HSP70 and the age of vaping initiation (rho = -0.289, p = 0.043), and a positive correlation with the duration of vaping sessions (rho = 0.292, p = 0.042), indicating that starting vaping at a young age and prolonging sessions may increase the expression of this protein.Conclusion Dual users of electronic cigarettes exhibit elevated salivary DKK1 levels and significant correlations with HSP70; these results suggest that chronic use may alter the inflammatory process. The pattern of e-cigarette consumption and the age of initiation modify salivary HSP70 levels. These proteins are involved in cellular stress and inflammatory mechanisms.
SN - 2296-2565
ER -