Figure 11.

Effects of e-cigarette vape (ECV) or tobacco cigarette smoking (TCS) exposure on superoxide generation in aortic and heart tissues. Animals from all groups were euthanized, and aorta and heart tissue were excised and embedded in OCT for fluorescence assay of superoxide generation using dihydroethidium (DHE), which reacts with superoxide to form a red fluorescent product. A and B: representative images from transverse sections of thoracic aortic for each exposure group at 16 and 60 wk of exposure, respectively. Superoxide dismutase mimetic (SODm; 100 µM) was used to confirm that the fluorescence was derived from superoxide as shown at rightmost column for TCS. C and D: representative images in heart tissues at 16 and 60 wk, respectively. E and F: quantitation of fluorescence intensity in thoracic aortic and heart tissues of each exposure group, respectively. Values are shown as %air-exposed control. Data are expressed as means ± SE of 7–9 aortic sections from 4 mice in each group. In ECV and TCS groups, superoxide production was increased in both aortic and heart tissues at week 16, with further increase at 60 wk of exposure, compared with tissue from air-control. ECV-0, ECV with 0 mg/mL NIC; ECV-6, 6 mg/mL NIC; ECV-24, 24 mg/mL NIC; NIC, nicotine. *Significant difference from air-exposed control at P < 0.05; +significant difference from TCS-exposed group at P < 0.05.