The toxic effects of electronic cigarette aerosol and cigarette smoke on cardiovascular, gastrointestinal and renal systems in mice

Electronic cigarette (EC) has been suggested to be less harmful than cigarette smoking, but the research on the full extent of their harm reduction potential is still lacking. This study aimed to evaluate the influence of EC aerosol and cigarette smoke (CS) on cardiovascular, gastrointestinal, and renal functions in mice after prolonged exposure. Forty-eight C57BL/6J male mice were randomly grouped and then exposed to fresh air (control), mung bean-flavored EC aerosol with low and high dose (EC1L, 6 mg/kg; EC1H, 12 mg/kg), watermelon-flavored EC aerosol with low and high dose (EC2L, 6 mg/kg; EC2H, 12 mg/kg), and finally a cigarette smoke (CS, 6 mg/kg), respectively. After 10 weeks of exposure, the heart rate increased for both the EC and CS groups, and the effect of CS on blood oxygen saturation was significantly higher than that of the EC group (P < 0.01). Proteomic analysis of the heart tissue showed that the overlapped differential expression protein from the EC and CS exposures was Crip2. For the gastrointestinal system, oral mucosa was significantly damaged in CS group. Compare with CS, EC had significantly fewer negative effects on most of the indictors which focused on in this study.