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Nishimura-Danjobara Y, Oyama K, Oyama TM, Yokoigawa K, Oyama Y. Modification of cell vulnerability to oxidative stress by N-(3-oxododecanoyl)-L-homoserine-lactone, a quorum sensing molecule, in rat thymocytes. Chem Biol Interact 2019; 302:143-148. [PMID: 30779908 DOI: 10.1016/j.cbi.2019.02.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2018] [Revised: 01/23/2019] [Accepted: 02/08/2019] [Indexed: 11/18/2022]
Abstract
N-(3-oxododecanoyl)-l-homoserine-lactone (ODHL), a quorum sensing molecule, affects intracellular Zn2+ concentration ([Zn2+]i) and cellular levels of nonprotein thiols ([NPT]i) of rat thymic lymphocytes, both of which are assumed to affect cell vulnerability to oxidative stress. Therefore, it is interesting to examine the effects of ODHL on the cells under oxidative stress. ODHL augmented the cytotoxicity of H2O2, but not calcium ionophore A23187. ODHL potentiated the H2O2-induced elevation of [Zn2+]i, wherein, it greatly attenuated the H2O2-induced increase in intracellular Ca2+ concentration. ODHL did not affect [NPT]i in the presence of H2O2. Therefore, we conclude that the elevation of [Zn2+]i is involved in the ODHL-induced potentiation of H2O2 cytotoxicity. Our findings suggest that ODHL modifies cell vulnerability to oxidative stress in host cells.
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Affiliation(s)
| | - Keisuke Oyama
- Sakai City Medical Center, Sakai, Osaka, 593-8304, Japan.
| | | | - Kumio Yokoigawa
- Bioscience and Bioindustry, Tokushima University, Tokushima, 770-8513, Japan.
| | - Yasuo Oyama
- Bioscience and Bioindustry, Tokushima University, Tokushima, 770-8513, Japan.
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2
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Inoue T, Kinoshita M, Oyama K, Kamemura N, Oyama Y. Captan-induced increase in the concentrations of intracellular Ca 2+ and Zn 2+ and its correlation with oxidative stress in rat thymic lymphocytes. ENVIRONMENTAL TOXICOLOGY AND PHARMACOLOGY 2018; 63:78-83. [PMID: 30172959 DOI: 10.1016/j.etap.2018.08.017] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/18/2018] [Revised: 08/19/2018] [Accepted: 08/26/2018] [Indexed: 06/08/2023]
Abstract
Captan, a phthalimide fungicide, is considered to be relatively nontoxic to mammals. There is a possibility that captan affects membrane and cellular parameters of mammalian cells, resulting in adverse effects, because of high residue levels. To test the possibility, we examined the effects of captan on rat thymic lymphocytes using flow-cytometry with appropriate fluorescent probes. Treatment with 10 and 30 μM captan induced apoptotic and necrotic cell death. Before cell death occurred, captan elevated the intracellular concentrations of Ca2+ and Zn2+ and decreased the concentration of cellular thiol compounds. These captan-induced phenomena are shown to cause cell death and are similar to those caused by oxidative stress. Captan also elevated the cytotoxicity of hydrogen peroxide. Results indicate that 10 and 30 μM captan cause cytotoxic effects on mammalian cells. Despite no report on the significant environmental toxicity hazard of captan in humans, it may exhibit adverse effects, described above, on wild organisms.
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Affiliation(s)
- Tomomi Inoue
- Faculty of Bioscience and Bioindustry, Tokushima University, Tokushima 770-8513, Japan
| | - Maika Kinoshita
- Faculty of Bioscience and Bioindustry, Tokushima University, Tokushima 770-8513, Japan
| | | | - Norio Kamemura
- Faculty of Life Sciences, Tokushima Bunri University, Tokushima 770-8514, Japan
| | - Yasuo Oyama
- Faculty of Bioscience and Bioindustry, Tokushima University, Tokushima 770-8513, Japan.
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3
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Ae M, Imura N, Inubushi T, Abe S, Yusuke B, Sugimoto M, Kamemura N. Biphenyl-induced cytotoxicity is mediated by an increase in intracellular Zn 2. Drug Chem Toxicol 2018; 42:430-435. [PMID: 30203682 DOI: 10.1080/01480545.2018.1499771] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
Biphenyl is found both in natural and anthropogenic sources and is used as a fungistat in the packaging of citrus fruits. Acute exposure to high levels of biphenyl has been observed to cause skin irritation and toxic effects on the liver and kidneys. However, the mechanisms of cytotoxicity induced by biphenyl are not yet well understood. In the present study, the cytotoxicity of biphenyl was studied by flow cytometry with fluorescent probes. Biphenyl at 100 μM significantly increased cell lethality after 3 h in rat thymocytes. In addition, biphenyl at 100 μM or more elevated intracellular Zn2+ levels. N,N,N',N'-Tetrakis(2-pyridylmethyl)ethylenediamine (TPEN), an intracellular and extracellular Zn2+ chelator, but not diethylenetriamine-N,N,N',N″,N″-pentaacetic acid (DTPA), a membrane-impermeable Zn2+ chelator, attenuated the biphenyl-induced increase in intracellular Zn2+ levels and cell death. These results suggested that biphenyl-induced cytotoxicity caused an increase in intracellular Zn2+ levels, which was dependent on internal Zn2+. Moreover, biphenyl led to an increase in sensitivity to oxidative stress, while TPEN inhibited this biphenyl-induced increase. Our findings revealed that biphenyl caused an increase in the intracellular free Zn2+ concentration, inducing cytotoxicity, cell death, and an increase in sensitivity to oxidative stress.
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Affiliation(s)
- Masamichi Ae
- a a Division of Bioscience and Bioindustry , Tokushima University , Tokushima , Japan
| | - Naohiro Imura
- a a Division of Bioscience and Bioindustry , Tokushima University , Tokushima , Japan
| | - Tomoko Inubushi
- b Faculty of Life Science , Tokushima Bunri University , Tokushima , Japan
| | - Shin Abe
- a a Division of Bioscience and Bioindustry , Tokushima University , Tokushima , Japan
| | - Bekki Yusuke
- c Faculty of Medicine , Tokushima University , Tokushima , Japan
| | - Mayumi Sugimoto
- d Institute of Biomedical Sciences , Tokushima University Graduate School , Tokushima , Japan
| | - Norio Kamemura
- a a Division of Bioscience and Bioindustry , Tokushima University , Tokushima , Japan
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4
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Miura Y, Chen X, Yamada S, Sugihara A, Enkhjargal M, Sun Y, Kuroda K, Satoh M, Oyama Y. Triclocarban-induced change in intracellular Ca²⁺ level in rat thymocytes: cytometric analysis with Fluo-3 under Zn²⁺-free conditions. ENVIRONMENTAL TOXICOLOGY AND PHARMACOLOGY 2014; 37:563-570. [PMID: 24562054 DOI: 10.1016/j.etap.2014.01.013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/31/2013] [Revised: 12/28/2013] [Accepted: 01/20/2014] [Indexed: 06/03/2023]
Abstract
Triclocarban (TCC) is an antimicrobial used in personal hygiene products. Recent health concerns arose after TCC was detected in the blood of human subjects who showered with soap containing TCC. In this study, the effect of TCC on intracellular Ca(2+) concentration in rat thymocytes was examined using Fluo-3, an indicator of intracellular Ca(2+). TCC at concentrations ranging from 0.1 μM to 3 μM increased intracellular Ca(2+) concentration biphasically: first by releasing Ca(2+) from intracellular Ca(2+) stores and then inducing Ca(2+) influx through store-operated Ca(2+) channels. The threshold TCC concentration to increase intracellular Ca(2+) concentration in this study was lower than the maximum TCC concentrations reported in human blood samples. Therefore, we anticipate that TCC at concentrations reported in human blood samples might disturb intracellular Ca(2+) signaling in human lymphocytes.
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Affiliation(s)
- Yukari Miura
- Laboratory of Cellular Signaling, Graduate School of Integrated Arts and Sciences, The University of Tokushima, Tokushima 770-8502, Japan
| | - Xiaohui Chen
- Laboratory of Cellular Signaling, Graduate School of Integrated Arts and Sciences, The University of Tokushima, Tokushima 770-8502, Japan
| | - Saki Yamada
- Laboratory of Cellular Signaling, Graduate School of Integrated Arts and Sciences, The University of Tokushima, Tokushima 770-8502, Japan
| | - Aya Sugihara
- Laboratory of Cellular Signaling, Graduate School of Integrated Arts and Sciences, The University of Tokushima, Tokushima 770-8502, Japan
| | - Molomjamts Enkhjargal
- Laboratory of Cellular Signaling, Graduate School of Integrated Arts and Sciences, The University of Tokushima, Tokushima 770-8502, Japan
| | - Yuanzhi Sun
- Laboratory of Cellular Signaling, Graduate School of Integrated Arts and Sciences, The University of Tokushima, Tokushima 770-8502, Japan
| | - Keiko Kuroda
- Laboratory of Cellular Signaling, Graduate School of Integrated Arts and Sciences, The University of Tokushima, Tokushima 770-8502, Japan
| | - Masaya Satoh
- Laboratory of Cellular Signaling, Graduate School of Integrated Arts and Sciences, The University of Tokushima, Tokushima 770-8502, Japan
| | - Yasuo Oyama
- Laboratory of Cellular Signaling, Graduate School of Integrated Arts and Sciences, The University of Tokushima, Tokushima 770-8502, Japan.
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Dórea JG, Farina M, Rocha JBT. Toxicity of ethylmercury (and Thimerosal): a comparison with methylmercury. J Appl Toxicol 2013; 33:700-11. [PMID: 23401210 DOI: 10.1002/jat.2855] [Citation(s) in RCA: 86] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2012] [Revised: 12/10/2012] [Accepted: 12/11/2012] [Indexed: 12/18/2022]
Abstract
Ethylmercury (etHg) is derived from the metabolism of thimerosal (o-carboxyphenyl-thio-ethyl-sodium salt), which is the most widely used form of organic mercury. Because of its application as a vaccine preservative, almost every human and animal (domestic and farmed) that has been immunized with thimerosal-containing vaccines has been exposed to etHg. Although methylmercury (meHg) is considered a hazardous substance that is to be avoided even at small levels when consumed in foods such as seafood and rice (in Asia), the World Health Organization considers small doses of thimerosal safe regardless of multiple/repetitive exposures to vaccines that are predominantly taken during pregnancy or infancy. We have reviewed in vitro and in vivo studies that compare the toxicological parameters among etHg and other forms of mercury (predominantly meHg) to assess their relative toxicities and potential to cause cumulative insults. In vitro studies comparing etHg with meHg demonstrate equivalent measured outcomes for cardiovascular, neural and immune cells. However, under in vivo conditions, evidence indicates a distinct toxicokinetic profile between meHg and etHg, favoring a shorter blood half-life, attendant compartment distribution and the elimination of etHg compared with meHg. EtHg's toxicity profile is different from that of meHg, leading to different exposure and toxicity risks. Therefore, in real-life scenarios, a simultaneous exposure to both etHg and meHg might result in enhanced neurotoxic effects in developing mammals. However, our knowledge on this subject is still incomplete, and studies are required to address the predictability of the additive or synergic toxicological effects of etHg and meHg (or other neurotoxicants).
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Affiliation(s)
- José G Dórea
- Department of Nutrition, Faculty of Health Sciences, Universidade de Brasilia, 70919-970, Brasilia, DF, Brazil.
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Xu M, Yang L, Wang Q. Chemical interactions of mercury species and some transition and noble metals towards metallothionein (Zn7MT-2) evaluated using SEC/ICP-MS, RP-HPLC/ESI-MS and MALDI-TOF-MS. Metallomics 2013; 5:855-60. [DOI: 10.1039/c3mt00016h] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Morita J, Teramachi A, Sanagawa Y, Toyson S, Yamamoto H, Oyama Y. Elevation of intracellular Zn2+ level by nanomolar concentrations of triclocarban in rat thymocytes. Toxicol Lett 2012; 215:208-13. [PMID: 23099084 DOI: 10.1016/j.toxlet.2012.10.012] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2012] [Revised: 10/14/2012] [Accepted: 10/15/2012] [Indexed: 12/16/2022]
Abstract
It was recently reported that nanomolar concentrations of triclocarban, an antimicrobial agent, were detected in human blood after the use of soap containing triclocarban. Due to the widespread use of triclocarban in adult and infant personal care products, the report prompted us to study its cytotoxicity. The cytotoxicity of triclocarban was examined in rat thymocytes by using a cytometric technique with propidium iodide for examining cell lethality, FluoZin-3-AM for monitoring the intracellular Zn(2+) level, and 5-chloromethylfluorescencein diacetate for estimating the cellular content of non-protein thiol. The incubation with triclocarban at nanomolar concentrations (50-500nM) for 1h did not affect cell lethality but significantly elevated the intracellular Zn(2+) level. The elevation of the intracellular Zn(2+) level by triclocarban was not significantly dependent on external Zn(2+) level. There was a negative correlation (r=-0.9225) between the effect on the intracellular Zn(2+) level and that on the cellular content of non-protein thiol. These results suggest that nanomolar concentrations of triclocarban decrease the cellular content of non-protein thiol, leading to intracellular Zn(2+) release. Since zinc plays physiological roles in mammalian cells, the percutaneous absorption of triclocarban from soap may, therefore, affect some cellular functions.
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Affiliation(s)
- Junpei Morita
- Division of Environmental Symbiosis Studies, Graduate School of Integrated Arts and Sciences, The University of Tokushima, Tokushima 770-8502, Japan
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Tamura I, Kanbara Y, Saito M, Horimoto K, Satoh M, Yamamoto H, Oyama Y. Triclosan, an antibacterial agent, increases intracellular Zn(2+) concentration in rat thymocytes: its relation to oxidative stress. CHEMOSPHERE 2012; 86:70-75. [PMID: 22000841 DOI: 10.1016/j.chemosphere.2011.09.009] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/22/2011] [Revised: 08/31/2011] [Accepted: 09/02/2011] [Indexed: 05/31/2023]
Abstract
Triclosan is used as an antibacterial agent in household items and personal care products. Since this compound is found in maternal milk of humans and bodies of wild animals, there is growing concern among some consumer groups and scientific community that triclosan is adverse for humans and wild animals. In order to estimate adverse actions of triclosan, the effects of triclosan on intracellular Zn(2+) concentration and cellular thiol content were studied in rat thymocytes by the use of flow cytometer with appropriate fluorescent probes. Triclosan at 1-3 μM (sublethal concentrations) increased the intensity of FluoZin-3 fluorescence (intracellular Zn(2+) concentration) and decreased the intensity of 5-chloromethylfluorescein (5-CMF) fluorescence (cellular thiol content). Negative correlation (r=-0.985) between triclosan-induced changes in FluoZin-3 and 5-CMF fluorescences was found. Removal of external Zn(2+) did not significantly affect the triclosan-induced augmentation of FluoZin-3 fluorescence, suggesting an intracellular Zn(2+) release by triclosan. These actions of triclosan were similar to those of H(2)O(2) and triclosan significantly potentiated the cytotoxicity of H(2)O(2). Therefore, the results may suggest that triclosan at sublethal concentrations induces oxidative stress that decreases cellular thiol content, resulting in an increase in intracellular Zn(2+) concentration by Zn(2+) release from intracellular store(s). Since recent studies show many physiological roles of intracellular Zn(2+) in cellular functions, the triclosan-induced disturbance of cellular Zn(2+) homeostasis may induce adverse actions on the cells.
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Affiliation(s)
- Ikumi Tamura
- Division of Environmental Symbiosis Studies, Graduate School of Integrated Arts and Sciences, The University of Tokushima, Tokushima 770-8502, Japan
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9
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Kinazaki A, Chen H, Koizumi K, Kawanai T, Oyama TM, Satoh M, Ishida S, Okano Y, Oyama Y. Putative role of intracellular Zn(2+) release during oxidative stress: a trigger to restore cellular thiol content that is decreased by oxidative stress. J Physiol Sci 2011; 61:403-9. [PMID: 21744294 PMCID: PMC10717562 DOI: 10.1007/s12576-011-0160-0] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2011] [Accepted: 06/19/2011] [Indexed: 12/21/2022]
Abstract
Although the ability of zinc to retard the oxidative process has been recognized for many years, zinc itself has been reported to induce oxidative stress. In order to give some insights into elucidating the role of intracellular Zn(2+) in cells suffering from oxidative stress, the effects of N-ethylmaleimide (NEM) and ZnCl(2) on cellular thiol content and intracellular Zn(2+) concentration were studied by use of 5-chloromethylfluorescein diacetate (5-CMF-DA) and FluoZin-3 pentaacetoxymethyl ester (FluoZin-3-AM) in rat thymocytes. The treatment of cells with NEM attenuated 5-CMF fluorescence and augmented FluoZin-3 fluorescence in a dose-dependent manner. These NEM-induced phenomena were observed under external Zn(2+)-free conditions. Results suggest that NEM decreases cellular thiol content and induces intracellular Zn(2+) release. Micromolar ZnCl(2) dose-dependently augmented both FluoZin-3 and 5-CMF fluorescences, suggesting that the elevation of intracellular Zn(2+) concentration increases cellular thiol content. Taken together, it is hypothesized that intracellular Zn(2+) release during oxidative stress is a trigger to restore cellular thiol content that is decreased by oxidative stress.
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Affiliation(s)
- Akio Kinazaki
- Graduate School of Pharmaceutical Sciences, Tokushima Bunri University, Tokushima, Japan
| | - Hongqin Chen
- Faculty of Integrated Arts and Sciences, The University of Tokushima, Tokushima, 770-8502 Japan
| | - Kazuki Koizumi
- Faculty of Integrated Arts and Sciences, The University of Tokushima, Tokushima, 770-8502 Japan
| | - Takuya Kawanai
- Faculty of Integrated Arts and Sciences, The University of Tokushima, Tokushima, 770-8502 Japan
| | - Tomohiro M. Oyama
- Hakata Clinic, Medical Co. LTA Clinical Pharmacology Center, Fukuoka, Japan
| | - Masaya Satoh
- Faculty of Integrated Arts and Sciences, The University of Tokushima, Tokushima, 770-8502 Japan
| | - Shiro Ishida
- Graduate School of Pharmaceutical Sciences, Tokushima Bunri University, Tokushima, Japan
| | - Yoshiro Okano
- Graduate School of Pharmaceutical Sciences, Tokushima Bunri University, Tokushima, Japan
| | - Yasuo Oyama
- Faculty of Integrated Arts and Sciences, The University of Tokushima, Tokushima, 770-8502 Japan
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Zinc at clinically-relevant concentrations potentiates the cytotoxicity of polysorbate 80, a non-ionic surfactant. Toxicol In Vitro 2010; 24:737-44. [PMID: 20079827 DOI: 10.1016/j.tiv.2010.01.004] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2009] [Revised: 12/09/2009] [Accepted: 01/11/2010] [Indexed: 11/23/2022]
Abstract
Polysorbate 80, a non-ionic surfactant, is used in the formula of water-insoluble anticancer agents for intravenous application. In our recent studies, this surfactant decreased cellular thiol content and the chemicals decreasing cellular thiol content increased intracellular Zn(2+) concentration. In this study using rat thymocytes, the effect of polysorbate 80 on FluoZin-3 fluorescence, an indicator for intracellular Zn(2+), and the influence of ZnCl(2) on cytotoxicity of polysorbate 80 were examined in order to test the possibility that Zn(2+) is involved in cytotoxic action of polysorbate 80. The surfactant at concentrations of 10 microg/ml or more significantly augmented FluoZin-3 fluorescent in a concentration-dependent manner, indicating an increase in intracellular Zn(2+) concentration. The increase by polysorbate 80 was also observed after removing extracellular Zn(2+), suggesting an intracellular Zn(2+) release. The simultaneous application of polysorbate 80 (30 microg/ml) and ZnCl(2) (10-30 microM) significantly increased cell lethality. The simultaneous application of ZnCl(2) accelerated the process of cell death induced by polysorbate 80 and the combination increased oxidative stress. Results may indicate that the cytotoxicity of polysorbate 80 at clinical concentrations is modified by micromolar zinc. Although there is no clinical report that polysorbate 80 and zinc salt are simultaneously applied to human as far as our knowledge, it may be speculated that zinc induces some diverse actions in cancer treatment with water-insoluble anticancer agent including nanoparticle drug of which the solvent is polysorbate 80.
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Methylmercury elicits intracellular Zn2+ release in rat thymocytes: Its relation to methylmercury-induced decrease in cellular thiol content. Toxicol Lett 2009; 191:231-5. [DOI: 10.1016/j.toxlet.2009.09.003] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2009] [Revised: 09/03/2009] [Accepted: 09/03/2009] [Indexed: 11/24/2022]
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Oyama TB, Oyama K, Kawanai T, Oyama TM, Hashimoto E, Satoh M, Oyama Y. Tri-n-butyltin increases intracellular Zn(2+) concentration by decreasing cellular thiol content in rat thymocytes. Toxicology 2009; 262:245-9. [PMID: 19559746 DOI: 10.1016/j.tox.2009.06.016] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2009] [Revised: 06/11/2009] [Accepted: 06/17/2009] [Indexed: 10/20/2022]
Abstract
Effect of tri-n-butyltin (TBT), an environmental pollutant, on intracellular Zn(2+) concentration was tested in rat thymocytes to reveal one of cytotoxic profiles of TBT at nanomolar concentrations using a flow cytometer and appropriate fluorescent probes. TBT at concentrations of 30 nM or more (up to 300 nM) significantly increased the intensity of FluoZin-3 fluorescence, an indicator for intracellular Zn(2+) concentration, under external Ca(2+)- and Zn(2+)-free condition. Chelating intracellular Zn(2+) completely attenuated the TBT-induced augmentation of FluoZin-3 fluorescence. Result suggests that nanomolar TBT releases Zn(2+) from intracellular store site. Oxidative stress induced by hydrogen peroxide also increased the FluoZin-3 fluorescence intensity. The effects of TBT and hydrogen peroxide on the fluorescence were additive. TBT-induced changes in the fluorescence of FluoZin-3 and 5-chloromethylfluorescein, an indicator for cellular thiol content, were correlated with a coefficient of -0.962. Result suggests that the intracellular Zn(2+) release by TBT is associated with TBT-induced reduction of cellular thiol content. However, chelating intracellular Zn(2+) potentiated the cytotoxicity of TBT. Therefore, the TBT-induced increase in intracellular Zn(2+) concentration may be a type of stress responses to protect the cells.
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Affiliation(s)
- Toshihisa B Oyama
- Laboratory of Cellular Signaling, Faculty of Integrated Arts and Sciences, The University of Tokushima, Tokushima 770-8502, Japan
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