Transcriptomic analysis reflects the different lung injury patterns of E-cigarette components VEA and PG in mice

Recently, thousands of cases of E-cigarette or vaping product use-associated lung injury (EVALI) were reported. But the lung toxicity of each E-cigarette components were still poorly defined. Major components of E-cigarette were nicotine, flavoring, vitamin E acetate (VEA), propylene glycol (PG) and vegetable glycerin (VG). In our previous study, we determine the different lung injury patterns in PG and VEA exposed mice; fibrotic injury in PG and asthmatic injury in VEA. In this study, we performed the transcriptomic analysis that could reflect different lung injury patterns caused by PG and VEA in lung tissues using RNS-Sequencing and bioinformatics tools. A combination of P-value <0.05 and fold change ≥1.5 was used to identify differently expressed genes (DEGs). Gene-expression data showed different gene-alteration patterns in the PG and VEA groups. Supervised analysis revealed that 1,193 PG and 1,795 VEA induced-specific genes, and functional analysis revealed that PG-specific genes were involved in TNC-related chronic obstructive pulmonary diseases, whereas VEA-specific genes were involved in asthma-related chronic lung injury. The results of transcriptomic analysis were consistent with lung histopathology results. These findings indicated that E-cigarette component-specific changes in gene expression closely reflected E-cigarette component pathological changes in E-cigarette component-induced lung injury. C57BL/6, 826 and 1,100 mg/mL of Propylene glycol (Sigma, P4347), 3.12, 6.25 and 12.5 mg/mL of Vitamin E acetate (Sigma, T3376), Intratracheal instillation, 50 uL/1time, 1time/1day, 14day-repeated treatment, Secrificed at day 15, RNA extraction form lung tissue after BALF