Figure 8. Cardiac inflammation induced by inhaled LPS challenge is increased in the setting of 3 months of JUUL aerosol inhalation.

Hearts were harvested, and RNA was extracted from the left ventricle and qPCR was performed to quantify the gene expression of different cytokines, chemokines and fibrosis-associated genes. Cytokines include Tnfa at (A) 1 month and (B) 3 months, Il1b at (C) 1 month and (D) 3 months, Il6 at (E) 1 month and (F) 3 months, and Il18 at (G) 1 month and (H) 3 months. Chemokines include Ccl2 at (I) 1 month and (J) 3 months, Ccl3 at (K) 1 month and (L) 3 months, Cxcl1 at (M) 1 month and (N) 3 months, and Cxcl2 at (O) 1 month and (P) 3 months. Fibrosis-associated genes include Col1a1 at (Q) 1 month and (R) 3 months, Col3a1 at (S) 1 month and (T) 3 months, Postn at (U) 1 month and (V) 3 months, and Tlr4 at (W) 1 month and (X) 3 months. Changes in expression levels are relative to Air controls. Data are presented as individual data points ± SEM with n = 5–11 mice per group. *p < 0.05, **p < 0.01, ***p < 0.001 and ****p < 0.0001.

Figure 8—figure supplement 1. Inflammatory gene expression changes in the hearts of mice exposed to JUUL Mango and JUUL Mint and challenged with inhaled LPS.

Mice exposed to JUUL Mint aerosols three times daily (60 min total) for 1 month prior to LPS challenge had increased expression of Tnfa, Il1b, Ccl2, Ccl3, Cxcl1, and Cxcl2, and decreased Postn, relative to air controls, while mice exposed to JUUL Mango aerosols for 1 month had increased Ccl2 and decreased Postn. After 3 months of JUUL Mint exposure, cardiac tissue had increased Il1b, Ccl2, Il1b, Ccl2, and Col3a1 in the setting of LPS challenge, while JUUL Mango had increased Il1b. Data were analyzed with one-way ANOVA with Holm-Sidak multiple comparisons for each gene of interest. Data are presented as individual data points ± SD with n = 5–6 mice per group. *p < 0.05, **p < 0.01, *** p < 0.001, and ****p < 0.0001.