ABSTRACT
Objective To investigate whether the metabolite of benzene, 1, 4-benzoquinone (1, 4-BQ) , can activate PINK1/Parkin-mediated mitocphagy and the role of reactive oxygen species (ROS) in 1, 4-BQ induced mitophagy in vitro. Methods Human promyelocytic leukemia cells HL60 were used as the test cells, and were divided into control group, 1, 4-BQ group (10 μM 1, 4-BQ treated cells for 24 h), NAC group (5 mM antioxidant N-acetyl cysteine treated cells for 24 h) and 1, 4-BQ+NAC group (5 mM NAC preincubated for 1 h prior to the treatment with 10 μM 1, 4-BQ for 24 h) . The ultra structure of the cells were observed by transmission electron microscopy (TEM), and the expression of mitophagy related protein LC3, PINK1 and Parkin were detected by Western blot, and the intracellular ROS content was determined by DCFH-DA staining. Results The mitochondria in the control group showed a normal rod-shaped structure with clear mitochondrial cristae, while in the 1, 4-BQ group, the mitochondria showed a swollen structure with less mitochondrial cristae, and typical double-membrane mitophagosomes were observed. LC3-Ⅱ/LC3-Ⅰ ratio, the expression of PINK1, Parkin protein and ROS content in 1, 4-BQ group were increased compared with the control group (P <0.05) , and this increase was markedly blocked by the co-treatment of 1, 4-BQ and NAC (P <0.05) . Conclusion The 1, 4-BQ can induce PINK1/Parkin-mediated mitophagy and ROS plays a significant role in 1, 4-BQ-induced mitophagy.