title: Antioxidant tert-butylhydroquinone ameliorates arsenic-induced intracellular damages and apoptosis through induction of Nrf2-dependent antioxidant responses as well as stabilization of anti-apoptotic factor Bcl-2 in human keratinocytes.
abstract: Human skin is a known target site of inorganic arsenic with effects ranging from hyperkeratosis to dermal malignancies. Tert-butylhydroquinone (tBHQ), approved food-grade phenolic antioxidant, is demonstrated to induce remarkable antioxidant activity in a variety of cells and tissues. The present study aimed at the protective effects of tBHQ on arsenic-induced cytotoxicity and apoptosis in human keratinocytes. Our results demonstrated that tBHQ antagonized arsenic-induced decrease of cell viability, generation of reactive oxygen species (ROS) and lipid peroxidation, as well as reduction of antioxidative enzymes superoxide dismutase (SOD) and catalase (CAT) activities. We also found that tBHQ relieved the G2/M phase arrest by arsenic exposure, which was associated with altering the expression of cell cycle regulators cyclin D1 and CDK4. tBHQ treatment further reduced the numbers of arsenic-induced mitochondrial-mediated apoptotic cells, which occurred concomitantly with the effective recovery of mitochondrial membrane potential (ΔΨm) depolarization, the release of cytochrome c releasing from the mitochondrial as well as the survival signal related factor caspase 3 activation. Our experiments then confirmed that tBHQ activated nuclear factor E2-related factor 2 (NRF2) pathway by increasing NRF2 protein in both nucleus and cytoplasm and upregulating NRF2 downstream targets
  
  
  
  quinine oxidoreductase 1 (NQO1) and heme oxygenase-1 (HO-1). More interestingly, arsenic-induced decrease of anti-apoptotic factor B-cell lymphoma-2 (Bcl-2) and increase of pro-apoptotic factor Bcl-2-associated X protein (Bax) could all be reversed by tBHQ pretreatment. These results suggested together that tBHQ could ameliorate arsenic-induced cytotoxicity and apoptosis, which might be linked with the induction of Nrf2-dependent antioxidant responses as well as stabilization of anti-apoptotic factor Bcl-2 in human keratinocytes.
authors.affiliation: Department of Occupational and Environmental Health, Key Laboratory of Arsenic-related Biological Effects and Prevention and Treatment in Liaoning Province, School of Public Health, China Medical University, No. 77 Puhe Road, Shenyang North New Area, Shenyang, Liaoning Province 110013, China.
authors.forename: Xiaoxu
authors.initials: X
authors.lastname: Duan
authors.affiliation: Department of Occupational and Environmental Health, Key Laboratory of Arsenic-related Biological Effects and Prevention and Treatment in Liaoning Province, School of Public Health, China Medical University, No. 77 Puhe Road, Shenyang North New Area, Shenyang, Liaoning Province 110013, China.
authors.forename: Jinlong
authors.initials: J
authors.lastname: Li
authors.affiliation: Health Care Department, Maternal and Child Health Care Center of Cangzhou, Cangzhou 061000, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Li
authors.affiliation: Student Office, China Medical University, Shenyang 110013, China.
authors.forename: Xiaoyue
authors.initials: X
authors.lastname: Xing
authors.affiliation: Department of Occupational and Environmental Health, Key Laboratory of Arsenic-related Biological Effects and Prevention and Treatment in Liaoning Province, School of Public Health, China Medical University, No. 77 Puhe Road, Shenyang North New Area, Shenyang, Liaoning Province 110013, China.
authors.forename: Yang
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: Department of Occupational and Environmental Health, Key Laboratory of Arsenic-related Biological Effects and Prevention and Treatment in Liaoning Province, School of Public Health, China Medical University, No. 77 Puhe Road, Shenyang North New Area, Shenyang, Liaoning Province 110013, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Li
authors.affiliation: Department of Occupational and Environmental Health, Key Laboratory of Arsenic-related Biological Effects and Prevention and Treatment in Liaoning Province, School of Public Health, China Medical University, No. 77 Puhe Road, Shenyang North New Area, Shenyang, Liaoning Province 110013, China.
authors.forename: Lu
authors.initials: L
authors.lastname: Zhao
authors.affiliation: Environment and Non-Communicable Diseases Research Center, School of Public Health, China Medical University, Shenyang 110013, China.
authors.forename: Guifan
authors.initials: G
authors.lastname: Sun
authors.affiliation: Department of Dermatology, No. 1 Hospital of China Medical University, Shenyang 110001, China. Electronic address: Gaobarry@hotmail.com.
authors.forename: Xing-Hua
authors.initials: XH
authors.lastname: Gao
authors.affiliation: Department of Occupational and Environmental Health, Key Laboratory of Arsenic-related Biological Effects and Prevention and Treatment in Liaoning Province, School of Public Health, China Medical University, No. 77 Puhe Road, Shenyang North New Area, Shenyang, Liaoning Province 110013, China. Electronic address: libing@mail.cmu.edu.cn.
authors.forename: Bing
authors.initials: B
authors.lastname: Li
mesh_terms: D000975:Antioxidants / Q000008:administration & dosage*; D017209:Apoptosis / Q000187:drug effects; D001151:Arsenic / Q000633:toxicity; D002374:Catalase / Q000378:metabolism; D002470:Cell Survival / Q000187:drug effects; D019938:Cyclin D1 / Q000378:metabolism; D051358:Cyclin-Dependent Kinase 4 / Q000378:metabolism; D003593:Cytoplasm / Q000187:drug effects / Q000378:metabolism / Q000473:pathology; D051547:Heme Oxygenase-1 / Q000378:metabolism; D006801:Humans; D006873:Hydroquinones / Q000008:administration & dosage*; D015603:Keratinocytes / Q000187:drug effects / Q000378:metabolism; D008928:Mitochondria / Q000187:drug effects / Q000378:metabolism / Q000473:pathology; D016660:NAD(P)H Dehydrogenase (Quinone) / Q000235:genetics* / Q000378:metabolism; D051267:NF-E2-Related Factor 2 / Q000235:genetics* / Q000378:metabolism; D018384:Oxidative Stress / Q000187:drug effects; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000235:genetics* / Q000378:metabolism; D017382:Reactive Oxygen Species / Q000378:metabolism; D013482:Superoxide Dismutase / Q000378:metabolism; D051028:bcl-2-Associated X Protein / Q000378:metabolism
chemical_list: D000975:Antioxidants; C494826:BAX protein, human; D006873:Hydroquinones; D051267:NF-E2-Related Factor 2; C495635:NFE2L2 protein, human; D019253:Proto-Oncogene Proteins c-bcl-2; D017382:Reactive Oxygen Species; D051028:bcl-2-Associated X Protein; D019938:Cyclin D1; C018855:2-tert-butylhydroquinone; D002374:Catalase; C496541:HMOX1 protein, human; D051547:Heme Oxygenase-1; D013482:Superoxide Dismutase; D016660:NAD(P)H Dehydrogenase (Quinone); C447479:NQO1 protein, human; C495900:CDK4 protein, human; D051358:Cyclin-Dependent Kinase 4; D001151:Arsenic
keywords: Apoptosis; Arsenic; Bcl-2; Human keratinocytes; NRF2; Oxidative stress; tBHQ