Multiplexed High Content Screening Analysis Reveals Reduced Toxicity Of A Prototypic Modified Risk Tobacco Product (pMRTP) As Compared To A Conventional Cigarette
Presented at SOT 2014 Annual Meeting
Exposure to Cigarette Smoke (CS) causes lung toxicity and increases the risk of developing Chronic Obstructive Pulmonary Disease and Cancer. Gaining insight into the cellular processes impacted upon exposure would be very useful to understand CS toxicity and aid the development of MRTP products. The aim of the study was to investigate the biological impact of a smoke condensate from a pMRTP product, compared to the reference cigarette 3R4F. For this purpose, we performed a High Content Screening (HCS) analysis on normal human bronchial epithelial cells. 13 multi-parametric indicators of cellular toxicity were measured over range of condensate concentrations and at different time points. Exposure to 3R4F resulted in increased cytotoxicity after 24h. Moreover, compared to vehicle control, 3R4F induced a dose-dependent increase in DNA damage at 4h and 24h. Genotoxicity was accompanied by cell growth arrest, consistent with activation of DNA repair, as well as dose-dependent responses on markers of cellular stress (ROS production, C-Jun activation and glutathione depletion), mitochondrial health (mitochondrial membrane potential and mitochondrial mass) and cellular integrity (cellular membrane permeability). Compared to 3R4F, exposure to a pMRTP product resulted in significant decreases in all tested endpoints at 4h and 24h and more than 90% decrease in cytotoxicity after 24h. In summary, we provide mechanistic insight into the mode of action of CS on lung cells, and how, by lessening the biological impact on key cellular processes, exposure to a pMRTP reduces overall toxicity when compared to CS. Moreover, the ability to detect biological perturbations at sub lethal doses strongly supports the use of HCS-based approaches for toxicological assessment.