In Vitro Exposure to Vaped Tetrahydrocannabinol Increases Candida albicans (SC5314) Growth, Metabolic Activity, Biofilm Formation, and the Expression of Virulence Genes

Vaping tetrahydrocannabinol (THC), a cannabis derivative, using electronic cigarettes (e-cigarettes) could deregulate oral health and lead to oral candidiasis. This study aimed to investigate the effects of vaped THC on <i>Candida albicans</i> growth, metabolic activity, biofilm formation, and the expression of virulence genes. Exposure to e-cigarette aerosol with or without nicotine and with or without 10% or 15% THC increased <i>C. albicans</i> growth and metabolic activity; the effects were more pronounced when THC was present in the e-cigarette aerosol. Biofilm analyses showed that e-cigarette aerosol with THC significantly promoted <i>C. albicans</i> biofilm formation, with the higher THC concentration (15%) having the greater effect. Consistently, e-cigarette aerosol with THC increased the expression of the virulence genes <i>EAP1</i>, <i>SAP2</i>, <i>SAP4</i>, and <i>SAP9</i>. These findings suggested that exposure to vaped THC could contribute to the pathogenesis of oral candidiasis, which may lead to oral health problems.