title: Polychlorinated biphenyl quinone induces mitochondrial-mediated and caspase-dependent apoptosis in HepG2 cells.
abstract: Polychlorinated biphenyl (PCB) quinones are known to cause toxic effects, but their mechanisms are quite unclear. In this study, we examined whether 2,3,5-trichloro-6-phenyl-[1,4]benzoquinone, PCB29-pQ, induces cell death via apoptosis pathway. Our result showed PCB29-pQ exposure decreased HepG2 cell viability in a time-dependent manner. Lactate dehydrogenase leakage assay also implied the cytotoxicity of PCB29-pQ. 4',6-Diamidino-2-phenylindole dihydrochloride staining and flow cytometry assays both confirmed PCB29-pQ caused dose-dependent apoptotic cell death in HepG2 cells. Furthermore, we found that PCB29-pQ exposure increased cellular reactive oxygen species (ROS) level, decreased mitochondrial membrane potential and induced the translocation of cytochrome c from mitochondria into cytosol in HepG2 cells. Moreover, PCB29-pQ exposure induced B-cell lymphoma 2 (Bcl-2) downregulation and Bcl-2-associated X (Bax) upregulation, poly(ADP-ribose) polymerase cleavage, accompanied with the increased caspase-3/9 and p53 expressions. Taking together, these results suggested PCB29-pQ induced HepG2 cells apoptosis through a ROS-driven, mitochondrial-mediated and caspase-dependent pathway.
authors.affiliation: Key Laboratory of Luminescence and Real-Time Analysis, College of Pharmaceutical Sciences, Ministry of Education, Southwest University, Chongqing, 400715, People's Republic of China.
authors.forename: Demei
authors.initials: D
authors.lastname: Xu
authors.affiliation: Key Laboratory of Luminescence and Real-Time Analysis, College of Pharmaceutical Sciences, Ministry of Education, Southwest University, Chongqing, 400715, People's Republic of China.
authors.forename: Lingrui
authors.initials: L
authors.lastname: Li
authors.affiliation: Key Laboratory of Luminescence and Real-Time Analysis, College of Pharmaceutical Sciences, Ministry of Education, Southwest University, Chongqing, 400715, People's Republic of China.
authors.forename: Lichao
authors.initials: L
authors.lastname: Liu
authors.affiliation: Key Laboratory of Luminescence and Real-Time Analysis, College of Pharmaceutical Sciences, Ministry of Education, Southwest University, Chongqing, 400715, People's Republic of China.
authors.forename: Hui
authors.initials: H
authors.lastname: Dong
authors.affiliation: Key Laboratory of Luminescence and Real-Time Analysis, College of Pharmaceutical Sciences, Ministry of Education, Southwest University, Chongqing, 400715, People's Republic of China.
authors.forename: Qin
authors.initials: Q
authors.lastname: Deng
authors.affiliation: Key Laboratory of Luminescence and Real-Time Analysis, College of Pharmaceutical Sciences, Ministry of Education, Southwest University, Chongqing, 400715, People's Republic of China.
authors.forename: Xiaojia
authors.initials: X
authors.lastname: Yang
authors.affiliation: Key Laboratory of Luminescence and Real-Time Analysis, College of Pharmaceutical Sciences, Ministry of Education, Southwest University, Chongqing, 400715, People's Republic of China.
authors.forename: Erqun
authors.initials: E
authors.lastname: Song
authors.affiliation: Key Laboratory of Luminescence and Real-Time Analysis, College of Pharmaceutical Sciences, Ministry of Education, Southwest University, Chongqing, 400715, People's Republic of China.
authors.forename: Yang
authors.initials: Y
authors.lastname: Song
mesh_terms: D017209:Apoptosis / Q000187:drug effects*; D016227:Benzoquinones / Q000737:chemistry / Q000633:toxicity*; D053148:Caspase 3 / Q000378:metabolism*; D053453:Caspase 9 / Q000378:metabolism; D045304:Cytochromes c / Q000378:metabolism; D056945:Hep G2 Cells; D006801:Humans; D053078:Membrane Potential, Mitochondrial / Q000187:drug effects; D008928:Mitochondria / Q000378:metabolism*; D011065:Poly(ADP-ribose) Polymerases / Q000378:metabolism; D011078:Polychlorinated Biphenyls / Q000737:chemistry / Q000633:toxicity*; D017382:Reactive Oxygen Species / Q000378:metabolism; D016159:Tumor Suppressor Protein p53 / Q000378:metabolism; D015854:Up-Regulation / Q000187:drug effects; D051028:bcl-2-Associated X Protein / Q000378:metabolism
chemical_list: C587734:2,3,5-trichloro-6-phenyl-(1,4)benzoquinone; D016227:Benzoquinones; D017382:Reactive Oxygen Species; D016159:Tumor Suppressor Protein p53; D051028:bcl-2-Associated X Protein; D045304:Cytochromes c; D011078:Polychlorinated Biphenyls; D011065:Poly(ADP-ribose) Polymerases; D053148:Caspase 3; D053453:Caspase 9
keywords: PCB; apoptosis; caspase; mitochondrial; quinone