Oxidative phosphorylation (OXPHOS) complexes expression in wild-type (WT) and DJ-1 knockout (KO) mice exposed to e-cigarette aerosol. A: mice were exposed to e-cigarette aerosol as described in materials and methods. COX IV, NDUFS1, ATP5A, SDHB, UQCRC2 and ND1 expression in murine lung tissue by Western blotting. B: protein expression was normalized to β-actin and densitometric quantification is also shown (e-cig, e-cigarette aerosol; *P < 0.05, **P < 0.001, n = 7 mice per group).