Figure 6.

Lipid peroxidation was increased in pulmonary arterial hypertension and NDUFA4L2 silencing‐mediated inhibition of hypoxia‐induced oxidative stress and mitochondrial dysfunction. A, Plasma 4‐HNE levels were determined by ELISA (n = 6); (B) After knockdown of NDUFA4L2 in HPASMCs in vitro, ELISA was detected the expression of lipid peroxidation metabolites 4‐HNE and MDA in different groups of Nor‐siNC, Hyp‐siNC and Hyp‐siNDUFA4L2 (n = 6); (C) Immunofluorescence was analysed the ROS release after interference with siNDUFA4L2 in HPASMCs (n = 6); (D) Representative images of six independent experiments showing MitoSOX intensity as a measure of mitochondrial superoxide levels (n = 6); ROS production was increased in hypoxia‐treated NC, which was reversed by silencing of NDUFA4L2; (E) Complex I activity was measured in HPASMCs transfected with siNC or NDUFA4L2 siRNA, then exposed to normoxic or hypoxic (3% O₂) conditions for 24 h (n = 6); (F) Oxygen consumption ratio in siNC or NDUFA4L2 siRNA, then exposed to normoxic or hypoxic (3% O₂) conditions for 24 h (n = 3). NC, negative control; Nor, normoxia; Hyp, hypoxia. *P < .05 vs donor or normoxia group; ^* P < .05, ^** P < .01, ^## P < .01, Scale bar = 100 μm. All of the values are denoted as mean ± SEM