ALBERT

Description:    Oxidative stress caused by reactive oxygen species (ROS) induces DNA base modifications and DNA strand breaks. In this study, the protective effect of baicalein against H 2 O 2 -induced DNA damage was investigated in V79-4 Chinese hamster fibroblast cells. H 2 O 2 treatment increased the levels of intracellular ROS and DNA double-strand breaks (DSBs) and decreased the level of Ku70 protein and the phosphorylation (activation) of DNA-dependent protein kinase catalytic subunit (DNA-PKcs), which are involved in the repair of DSBs by nonhomologous end joining. Baicalein effectively scavenged intracellular ROS induced by H 2 O 2 , reduced DSBs, and rescued Ku70 protein level and phosphorylation of DNA-PKcs. In cellular response to DNA base damage, 8-oxoguanine DNA glycosylase 1 (OGG1) plays a vital role in the removal of 8-oxoguanine (8-OxoG), which is formed mainly by oxidative stress. Baicalein significantly decreased the levels of 8-OxoG induced by H 2 O 2 , and this correlated with increases in OGG1 promoter activity and OGG1 mRNA and protein expression. The phosphorylated form of Akt kinase, which is a regulator of OGG1, was sharply decreased by H 2 O 2 , but was prevented by baicalein. A specific Akt inhibitor abolished the cytoprotective effects of baicalein, suggesting that OGG1 induction by baicalein involves the Akt pathway. In conclusion, baicalein exerted protective effects against DNA damage induced by oxidative stress by activating DNA repair systems and scavenging ROS. Content Type Journal Article Category Original Research Pages 1-13 DOI 10.1007/s10565-012-9233-y Authors Ki Cheon Kim, School of Medicine and Applied Radiological Science Research Institute, Jeju National University, Jeju, 690-756 Republic of Korea In Kyung Lee, Department of Obstetrics and Gynecology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, 138-736 Republic of Korea Kyoung Ah Kang, School of Medicine and Applied Radiological Science Research Institute, Jeju National University, Jeju, 690-756 Republic of Korea Hye Sun Kim, Cancer Research Institute, College of Medicine, Seoul National University, Seoul, 110-799 Republic of Korea Sam Sik Kang, College of Pharmacy, Seoul National University, Seoul, 151-742 Republic of Korea Jin Won Hyun, School of Medicine and Applied Radiological Science Research Institute, Jeju National University, Jeju, 690-756 Republic of Korea Journal Cell Biology and Toxicology Online ISSN 1573-6822 Print ISSN 0742-2091

Description:    We explored if epigenetic mechanisms could be involved in the down-regulated expression of catalase gene ( CAT) in the doxorubicin-resistant acute myelogenous leukemia (AML)-2/DX100 cells. Down-regulated CAT expression in AML-2/DX100 cells was completely recovered after treatment of hydrogen peroxide (H 2 O 2 ) and histone deacetylase inhibitor, trichostatin A (TSA) but was increased slightly by the treatment of DNA methylation inhibitor, 5-aza-2′-deoxycytidine (5-AdC). Bisulfite-sequencing PCR revealed that a CpG island of CAT was not methylated in AML-2/DX100 cells. Chromatin immunoprecipitation assay confirmed that acetylation of histone H4 in AML-2/DX100 cells significantly decreased as compared with that in AML-2/WT cells, which was significantly increased by TSA more than 5-AdC. Meanwhile, overexpression of other up-regulated peroxidase genes appears to make compensation for decreased H 2 O 2 -scavenging activity for the down-regulated CAT expression in AML-2/DX100 cells. These results suggest that histone H4 deacetylation is responsible for the down-regulated CAT expression in AML-2/DX100 cells, which are well adapted to oxidative stress. Content Type Journal Article Category Original Research Pages 11-18 DOI 10.1007/s10565-011-9201-y Authors Tae-Bum Lee, Research Center for Resistant Cells, Chosun University Medical School, Chosun University, Gwangju, 501-759 Republic of Korea Young-Sook Moon, Research Center for Resistant Cells, Chosun University Medical School, Chosun University, Gwangju, 501-759 Republic of Korea Cheol-Hee Choi, Research Center for Resistant Cells, Chosun University Medical School, Chosun University, Gwangju, 501-759 Republic of Korea Journal Cell Biology and Toxicology Online ISSN 1573-6822 Print ISSN 0742-2091 Journal Volume Volume 28 Journal Issue Volume 28, Number 1

Description:    The pseudo-tumoral expansion of fibroblast-like synoviocytes is a hallmark of rheumatoid arthritis (RA), and targeting rheumatoid arthritis fibroblast-like synoviocytes (RAFLSs) may have therapeutic potentials in this disease. Andrographolide, a diterpenoid compound isolated from the herb Andrographis paniculata , has been reported to have potent anti-inflammatory activity. In the present study, we aimed to investigate the effects of andrographolide on human RAFLSs and the underlying molecular mechanism(s). RAFLSs were isolated from patients with RA and treated with or without various concentrations (i.e., 10, 20, and 30 μM) of andrographolide for 48 h. 3-[4,5-Dimethyl-2-yl]-2,5-diphenyl tetrazolium bromide assay revealed that andrographolide treatment decreased the proliferation of RAFLSs in a dose-dependent manner. Cell cycle analysis using propidium iodide (PI) staining showed a G0/G1 cell cycle arrest in andrographolide-treated RAFLSs. Immunoblotting analysis of key cell cycle regulators demonstrated that andrographolide treatment caused a dose-dependent increase in the expression of cell-cycle inhibitors p21 and p27 and a concomitant reduction of cyclin-dependent kinase 4. Exposure to andrographolide-induced apoptosis of RAFLSs measured by annexin V/PI double staining, which was coupled with promotion of cytochrome C release from mitochondria and activation of caspase-3. Moreover, andrographolide-treated RAFLSs displayed a significant decrease in the Bcl-2/Bax ratio compared to untreated cells. In conclusion, our data demonstrate that andrographolide exerts anti-growth and pro-apoptotic effects on RAFLSs, thus may have therapeutic potential for the treatment of RA. Content Type Journal Article Pages 47-56 DOI 10.1007/s10565-011-9204-8 Authors Jie Yan, Faculty of Forensic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030 China Yang Chen, Faculty of Forensic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030 China Chao He, Faculty of Forensic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030 China Zhen-zhen Yang, Faculty of Forensic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030 China Cheng Lü, Faculty of Forensic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030 China Xin-shan Chen, Faculty of Forensic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030 China Journal Cell Biology and Toxicology Online ISSN 1573-6822 Print ISSN 0742-2091 Journal Volume Volume 28 Journal Issue Volume 28, Number 1

Description:    Selenium is an essential trace element for mammals. Through selenoproteins, this mineral participates in various biological processes such as antioxidant defence, thyroid hormone production, and immune responses. Some reports indicate that a human organism deficient in selenium may be prone to certain diseases. Adverse health effects following selenium overexposure, although very rare, have been found in animals and people. Contrary to selenium, arsenic and cadmium are regarded as toxic elements. Both are environmental and industrial pollutants, and exposure to excessive amounts of arsenic or cadmium can pose a threat to many people’s health, especially those living in polluted regions. Two other elements, vanadium and chromium(III) in trace amounts are believed to play essential physiological functions in mammals. This review summarizes recent studies on selenium interactions with arsenic and cadmium and selenium interactions with vanadium and chromium in mammals. Human studies have demonstrated that selenium may reduce arsenic accumulation in the organism and protect against arsenic-related skin lesions. Selenium was found to antagonise the prooxidant and genotoxic effects of arsenic in rodents and cell cultures. Also, studies on selenium effects against oxidative stress induced by cadmium in various animal tissues produced promising results. Reports suggest that selenium protection against toxicity of arsenic and cadmium is mediated via sequestration of these elements into biologically inert conjugates. Selenium-dependent antioxidant enzymes probably play a secondary role in arsenic and cadmium detoxification. So far, few studies have evaluated selenium effects on chromium(III) and vanadium actions in mammals. Still, they show that selenium may interact with these minerals. Taken together, the recent findings regarding selenium interaction with other elements extend our understanding of selenium biological functions and highlight selenium as a potential countermeasure against toxicity induced by arsenic and cadmium. Content Type Journal Article Pages 31-46 DOI 10.1007/s10565-011-9203-9 Authors Iwona Zwolak, Department of Cell Biology, Institute of Environmental Protection, John Paul II Catholic University of Lublin, Kraśnicka Ave. 102, 20-718 Lublin, Poland Halina Zaporowska, Department of Cell Biology, Institute of Environmental Protection, John Paul II Catholic University of Lublin, Kraśnicka Ave. 102, 20-718 Lublin, Poland Journal Cell Biology and Toxicology Online ISSN 1573-6822 Print ISSN 0742-2091 Journal Volume Volume 28 Journal Issue Volume 28, Number 1

Description:    Sensitivity of baker’s yeast to disulfiram (DSF) and hypersensitivity of a mutant devoid of Cu, Zn-superoxide dismutase to this compound is reported, demonstrating that yeast may be a simple convenient eukaryotic model to study the mechanism of DSF toxicity. DSF was found to induce oxidative stress in yeast cells demonstrated by increased superoxide production and decrease of cellular glutathione content. Anoxic atmosphere and hydrophilic antioxidants (ascorbate, glutathione, dithiothreitol, cysteine, and N -acetylcysteine) ameliorated DSF toxicity to yeast indicating that oxidative stress plays a critical role in the cellular action of DSF. Content Type Journal Article Category Original Research Pages 1-9 DOI 10.1007/s10565-011-9200-z Authors Magdalena Kwolek-Mirek, Department of Biochemistry and Cell Biology, University of Rzeszow, ul. Zelwerowicza 4, 35-601 Rzeszow, Poland Renata Zadrag-Tecza, Department of Biochemistry and Cell Biology, University of Rzeszow, ul. Zelwerowicza 4, 35-601 Rzeszow, Poland Grzegorz Bartosz, Department of Biochemistry and Cell Biology, University of Rzeszow, ul. Zelwerowicza 4, 35-601 Rzeszow, Poland Journal Cell Biology and Toxicology Online ISSN 1573-6822 Print ISSN 0742-2091 Journal Volume Volume 28 Journal Issue Volume 28, Number 1

Description:    This laboratory has generated a series of seven cadmium (Cd +2 )- and six arsenite (As +3 )-transformed urothelial cancer cell lines by exposure of parental UROtsa cells to each agent under similar conditions of exposure. In this study, the seven Cd +2 -transformed cell lines were characterized for the expression of keratin 6, 16, and 17 while the six As +3 cell lines were assessed for the expression of keratin 7 and 19. The results showed that the series of Cd +2 -transformed cell lines and their respective transplants all had expression of keratin 6, 16, and 17 mRNA and protein. The expression of keratin 6, 16, and 17 was also correlated with areas of the urothelial tumor cells that had undergone squamous differentiation. The results also showed that four of the six As +3 -transformed cell lines had expression of keratin 7 and 19 mRNA and protein and produced subcutaneous tumors with intense focal staining for keratin 7 and 19. The other two As +3 -transformed cell lines had very low expression of keratin 7 mRNA and protein and produced subcutaneous tumors having no immunoreactivity for keratin 7; although keratin 19 expression was still present. The peritoneal tumors produced by one of these two cell lines regained expression of keratin 7 protein. The present results, coupled with previous studies, indicate that malignant transformation of UROtsa cells by Cd +2 or As +3 produce similar patterns of keratin 6, 7, 16, 17, and 19 in the resulting series of cell lines and their respective tumors. Content Type Journal Article Pages 381-396 DOI 10.1007/s10565-010-9169-z Authors Seema Somji, Department of Pathology, School of Medicine and Health Sciences, University of North Dakota, 501 N. Columbia Road, Grand Forks, ND 58202, USA Ling Cao, Department of Pathology, School of Medicine and Health Sciences, University of North Dakota, 501 N. Columbia Road, Grand Forks, ND 58202, USA Aaron Mehus, Department of Pathology, School of Medicine and Health Sciences, University of North Dakota, 501 N. Columbia Road, Grand Forks, ND 58202, USA Xu Dong Zhou, Department of Pathology, School of Medicine and Health Sciences, University of North Dakota, 501 N. Columbia Road, Grand Forks, ND 58202, USA Mary Ann Sens, Department of Pathology, School of Medicine and Health Sciences, University of North Dakota, 501 N. Columbia Road, Grand Forks, ND 58202, USA Jane R. Dunlevy, Department of Anatomy and Cell Biology, School of Medicine and Health Sciences, University of North Dakota, Grand Forks, ND 58202, USA Scott H. Garrett, Department of Pathology, School of Medicine and Health Sciences, University of North Dakota, 501 N. Columbia Road, Grand Forks, ND 58202, USA Yun Zheng, Department of Pathology, School of Medicine and Health Sciences, University of North Dakota, 501 N. Columbia Road, Grand Forks, ND 58202, USA Jennifer L. Larson, Department of Anatomy and Cell Biology, School of Medicine and Health Sciences, University of North Dakota, Grand Forks, ND 58202, USA Donald A. Sens, Department of Pathology, School of Medicine and Health Sciences, University of North Dakota, 501 N. Columbia Road, Grand Forks, ND 58202, USA Journal Cell Biology and Toxicology Online ISSN 1573-6822 Print ISSN 0742-2091 Journal Volume Volume 27 Journal Issue Volume 27, Number 6

Description:    The main objectives of this work were to evaluate the effects of hydrogen sulfide on oxidative stress and cytotoxicity parameters in HepG2 cells and to assess the extent to which cytochrome P450 2E1 (CYP2E1) activity modulates the effects of hydrogen sulfide on oxidative stress and cytotoxicity. Sodium hydrosulfide (NaHS) caused time- and concentration-dependent cytotoxicity in both non-P450-expressing HepG2 cells (C34 cells) and CYP2E1-overexpressing HepG2 cells (E47 cells); however, NaHS-dependent cytotoxicity was higher in E47 than C34 cells. Cytotoxicity by NaHS in C34 and E47 cells was mainly necrotic in nature and associated with an early decrease in mitochondrial membrane potential. NaHS caused increased oxidation of lipophilic (C11-BODIPY 581/591 ) and hydrophilic (DCFH-DA) probes only in E47 cells, at a time point prior to overt cytotoxicity. Trolox, an amphipathic antioxidant, partially inhibited both the cytotoxicity and the increased oxidative stress detected in E47 cells exposed to NaHS. Cell-permeable iron chelators and CYP2E1 inhibitors significantly inhibited the oxidation of C11-BODIPY 581/591 in E47 cells in the presence of NaHS. NaHS produced lipid peroxidation and cytotoxicity in E47 cells supplemented with a representative polyunsaturated fatty acid (docosahexaenoic acid) but not in C34 cells; these effects were inhibited by α-tocopherol, a lipophilic antioxidant. These data suggest that CYP2E1 enhances H 2 S-dependent cytotoxicity in HepG2 cells through the generation of iron-dependent oxidative stress and lipid peroxidation. Content Type Journal Article Pages 439-453 DOI 10.1007/s10565-011-9198-2 Authors Andres A. Caro, Chemistry Department, Hendrix College, 1600 Washington Avenue, Conway, AR 72032, USA Sarah Thompson, Chemistry Department, Hendrix College, 1600 Washington Avenue, Conway, AR 72032, USA Jonathan Tackett, Chemistry Department, Hendrix College, 1600 Washington Avenue, Conway, AR 72032, USA Journal Cell Biology and Toxicology Online ISSN 1573-6822 Print ISSN 0742-2091 Journal Volume Volume 27 Journal Issue Volume 27, Number 6

Description: Introduction   Cytochrome P450 epoxygenases metabolize arachidonic acid to epoxyeicosatrienoic acids (EETs), which in turn are converted to dihydroxyeicosatrienoic acids (DHETs) by soluble epoxide hydrolase (sEH). EETs are known to modulate a number of vascular and renal functions, but the exact signaling mechanism(s) of these EET-mediated effects remains unknown. Purpose   The purpose of this study is to investigate the role of EETs and DHETs in regulating cyclic adenosine monophosphate (cAMP) production via adenylyl cyclase in a human embryonic kidney cell line (HEK293). Method   HEK293 cells were treated with vehicle, forskolin, epinephrine, 11,12-EET, 11,12-DHET, as well as potential pathway and G-protein inhibitors to assess changes in cAMP production. Results   Co-administering 11,12-EET with forskolin effectively eliminated the increased cAMP levels observed in cells treated with forskolin alone. The inhibitory effect of EETs on forskolin-mediated cAMP production was abolished when cells were treated with a sEH inhibitor ( t AUCB). 11,12-DHET also negated the effects of forskolin, suggesting that the inhibitory effect observed in EET-treated cells could be attributed to the downstream metabolites, DHETs. In contrast, inhibition of phosphodiesterase IV (PDE4) with rolipram eliminated the effects of EETs or DHETs, and inhibition of Gαi with pertussis toxin also resulted in enhanced cAMP production. Conclusion   Our data suggest that DHETs regulate cAMP production via PDE4 and Gαi protein. Moreover, they provide novel evidence as to how EET-mediated signaling may alter G-protein coupling in HEK293 cells. Content Type Journal Article Pages 321-332 DOI 10.1007/s10565-011-9190-x Authors Mohamed Abukhashim, Faculty of Pharmacy and Pharmaceutical Sciences, University of Alberta, Edmonton, AB T6G 2N8, Canada Glenis J. Wiebe, Faculty of Pharmacy and Pharmaceutical Sciences, University of Alberta, Edmonton, AB T6G 2N8, Canada John M. Seubert, Faculty of Pharmacy and Pharmaceutical Sciences, University of Alberta, Edmonton, AB T6G 2N8, Canada Journal Cell Biology and Toxicology Online ISSN 1573-6822 Print ISSN 0742-2091 Journal Volume Volume 27 Journal Issue Volume 27, Number 5

Description:    We describe a Saccharomyces cerevisiae bioluminescence assay for UV and arsenate in which bacterial luciferase genes are regulated by the promoter of the yeast gene, UFO1 . UFO1 encodes the F-box subunit of the Skp1–Cdc53–F-box protein ubiquitin ligase complex and is induced by DNA damage and by arsenate. We engineered the UFO1 promoter into an existing yeast bioreporter that employs human genes for detection of steroid hormone-disrupting compounds in water bodies. Our analysis indicates that use of an endogenous yeast promoter in different mutant backgrounds allows discrimination between different environmental signals. The UFO1 -engineered yeast give a robust bioluminescence response to UVB and can be used for evaluating UV protective sunscreens. They are also effective in detecting extremely low concentrations of arsenate, particularly in pdr5Δ mutants that lack a mechanism to extrude toxic chemicals; however, they do not respond to cadmium or mercury. Combined use of endogenous yeast promoter elements and mutants of stress response pathways may facilitate development of high-specificity yeast bioreporters able to discriminate between closely related chemicals present together in the environment. Content Type Journal Article Pages 227-236 DOI 10.1007/s10565-011-9184-8 Authors Anya Bakhrat, Department of Life Sciences, Faculty of Natural Sciences, Ben-Gurion University of the Negev, Beersheba, 84105 Israel Evgeni Eltzov, Unit of Environmental Engineering, Ben-Gurion University of the Negev, Beersheba, 84105 Israel Yishay Finkelstein, Department of Life Sciences, Faculty of Natural Sciences, Ben-Gurion University of the Negev, Beersheba, 84105 Israel Robert S. Marks, Department of Biotechnology Engineering, Faculty of Engineering Science, Ben-Gurion University of the Negev, Beersheba, 84105 Israel Dina Raveh, Department of Life Sciences, Faculty of Natural Sciences, Ben-Gurion University of the Negev, Beersheba, 84105 Israel Journal Cell Biology and Toxicology Online ISSN 1573-6822 Print ISSN 0742-2091 Journal Volume Volume 27 Journal Issue Volume 27, Number 3

Description:    Several asbestos-like mineral fibres, including fluoro-edenite, may cause lung cancer and/or other lung diseases. However, biological and molecular mechanisms linked to cancer development after mineral fibre exposure have not been fully investigated. In the present study, human non-malignant mesothelial (MeT-5A) and human bronchoalveolar alveolar epithelial (A549) cell lines were incubated with rising concentrations of fluoro-edenite to evaluate the expression of retinoblastoma (Rb) protein, which has been demonstrated to play an important role in cell cycle control and tumour progression. Intriguingly, these results show that Rb expression was unchanged, while the level of the phosphorylated protein increased significantly in a dose-dependent manner, suggesting an involvement of this regulator protein in the pathogenesis of the lung diseases induced by mineral fibres. In conclusion, fluoro-edenite regulates the expression of phospho-retinoblastoma to trigger a network of signals strictly connected with cell proliferation and neoplastic cell transformation. Content Type Journal Article Pages 217-225 DOI 10.1007/s10565-011-9183-9 Authors Giuseppe Musumeci, Department of Anatomy, Diagnostic Pathology, Forensic Medicine, Hygiene and Public Health, University of Catania, Via S. Sofia 87, 95123 Catania, Italy Venera Cardile, Department of Physiological Sciences, University of Catania, Via Andrea Doria 6, 95123 Catania, Italy Concettina Fenga, Section of Occupational Medicine, Department of Social and Environmental Medicine, University of Messina, Via Consolare Valeria, Gazzi, 98124 Messina, Italy Silvia Caggia, Department of Physiological Sciences, University of Catania, Via Andrea Doria 6, 95123 Catania, Italy Carla Loreto, Department of Anatomy, Diagnostic Pathology, Forensic Medicine, Hygiene and Public Health, University of Catania, Via S. Sofia 87, 95123 Catania, Italy Journal Cell Biology and Toxicology Online ISSN 1573-6822 Print ISSN 0742-2091 Journal Volume Volume 27 Journal Issue Volume 27, Number 3