Renal Cytotoxicity of the E-Vaping Flavoring Agent Menthol

Abstract ID 129161 Poster Board 414 E-cigarette and vaping device use has increased especially in teenagers and young adults. The health effects from exposure to the various components is not well understood. Menthol is a flavoring agent contained in vaping products and menthol is detectable in plasma following vaping. The purpose of this project was to evaluate the effect of menthol on renal proximal tubular epithelial cells. The overall hypothesis was that menthol is cytotoxic to HK-2 cells by impairing mitochondrial function. Human HK-2 cells were plated and equilibrated for 48 h. Cells were then exposed to 0-1500 uM menthol for 24 h. Studies were conducted as 4 independent experiments with different cell passages. Differences between groups were evaluated using ANOVA followed by a post hoc test. Cytotoxicity was assessed using the MTT assay after the 24 h exposure. MTT in viable cells was converted to formazan. No change in MTT occurred for cells exposed to 0-200 uM menthol. Further studies examined 0-1500 uM menthol. Menthol was cytotoxic between 200-1500uM compared to vehicle control (p<0.05). Studies examined autophagy markers LC3BII and II by western blot which showed no difference between groups exposed to 0-200 uM menthol. LC3BII was increased by 1500 uM menthol. Additional studies examined mitochondrial function following a 24 h exposure to menthol. In summary, menthol impaired cell function in HK-2 cells within 24 h. In summary, menthol impaired cell function in HK-2 cells within 24 h. Mitochondrial impairment occurred at lower concentrations than impacted by MTT and cell membrane integrity. (Supported by NIH Grant P20GM103434). Supported by NIH Grant P20GM103434.