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Cengiz O, Baran M, Balcioglu E, Suna PA, Bilgici P, Goktepe O, Onder GO, Goc R, Yay A. Use of selenium to ameliorate doxorubicin induced hepatotoxicity by targeting pro-inflammatory cytokines. Biotech Histochem 2020; 96:67-75. [PMID: 32400214 DOI: 10.1080/10520295.2020.1760353] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Doxorubicin (DOX) is a widely used drug for the treatment of cancer,but its clinical use is limited by its liver toxicity. Administering DOX with an antioxidant has become a strategy for preventing the side effects of DOX. Although selenium (Se) is an important trace mineral, data concerning the effect of Se on DOX induced liver tissue are lacking. We investigated the mechanism of DOX hepatotoxicity and the protective effect of different doses of Se on Dox induced liver damage. Female Wistar albino rats were divided into eight equal groups. Se was injected intraperitoneally (i.p.) to rats at doses of 0.5, 1, and 2 mg 0.5 h after injection i.p. of 5 mg/kg DOX on days 1, 7, 14, 21 and 28. Liver histopathology was assessed to determine the dose at which Se may best inhibit Dox induced liver toxicity. Also, tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β) expression levels and proliferating cell nuclear antigen (PCNA) activity were determined using immunohistochemistry. We found that DOX caused liver damage and increased TNF-α, IL-1β and PCNA levels. Se prevented structural damage to liver tissues. Our findings reinforce the protective effects of Se in rat liver.
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Affiliation(s)
- Ozge Cengiz
- Faculty of Medicine, Department of Histology and Embryology, Erciyes University , Kayseri, Turkey
| | - Munevver Baran
- Department of Pharmaceutical Basic Science, Faculty of Pharmacy, Erciyes University , Kayseri, Turkey
| | - Esra Balcioglu
- Faculty of Medicine, Department of Histology and Embryology, Erciyes University , Kayseri, Turkey.,Genome and Stem Cell Center (GENKOK), Erciyes University , Kayseri, Turkey
| | - Pinar Alisan Suna
- Faculty of Medicine, Department of Histology and Embryology, Erciyes University , Kayseri, Turkey
| | - Pınar Bilgici
- Faculty of Medicine, Department of Histology and Embryology, Erciyes University , Kayseri, Turkey
| | - Ozge Goktepe
- Faculty of Medicine, Department of Histology and Embryology, Erciyes University , Kayseri, Turkey
| | - Gozde Ozge Onder
- Faculty of Medicine, Department of Histology and Embryology, Erciyes University , Kayseri, Turkey
| | - Rumeysa Goc
- Faculty of Medicine, Department of Histology and Embryology, Erciyes University , Kayseri, Turkey
| | - Arzu Yay
- Faculty of Medicine, Department of Histology and Embryology, Erciyes University , Kayseri, Turkey.,Genome and Stem Cell Center (GENKOK), Erciyes University , Kayseri, Turkey
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Aydin S, Erkekoglu P, Başaran N, Kocer-Gumusel B. Impact of selenium status on Aroclor 1254-induced DNA damage in sperm and different tissues of rats. Toxicol Mech Methods 2017; 28:252-261. [DOI: 10.1080/15376516.2017.1397234] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Affiliation(s)
- Sevtap Aydin
- Department of Pharmaceutical Toxicology, Faculty of Pharmacy, Hacettepe University, Ankara, Turkey
| | - Pinar Erkekoglu
- Department of Pharmaceutical Toxicology, Faculty of Pharmacy, Hacettepe University, Ankara, Turkey
| | - Nurşen Başaran
- Department of Pharmaceutical Toxicology, Faculty of Pharmacy, Hacettepe University, Ankara, Turkey
| | - Belma Kocer-Gumusel
- Department of Pharmaceutical Toxicology, Faculty of Pharmacy, Hacettepe University, Ankara, Turkey
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3
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Song L, Guo L, Li Z. Molecular mechanisms of 3,3'4,4',5-pentachlorobiphenyl-induced epithelial-mesenchymal transition in human hepatocellular carcinoma cells. Toxicol Appl Pharmacol 2017; 322:75-88. [PMID: 28284859 DOI: 10.1016/j.taap.2017.03.003] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2016] [Revised: 02/28/2017] [Accepted: 03/04/2017] [Indexed: 02/07/2023]
Abstract
Polychlorinated biphenyls (PCBs) are classic persistent organic pollutants (POPs). Many studies have found a positive association between the progression of hepatocellular carcinoma (HCC) and PCBs exposure. However, the influence of PCBs on epithelial-mesenchymal transition (EMT) of HCC remains to be unclear. In this study, we explored the effect of PCB126 on EMT in HCC cells and its underlying mechanisms. The data showed that PCB126, exposing both Bel-7402 and SMMC-7721 cells for 48h, promoted EMT that was demonstrated by E-cadherin repression, up-regulation of N-cadherin and vimentin, and morphological alteration. We found that signal transducer and activator of transcription 3 (STAT3)/Snail1 signaling was activated after PCB126 exposure, and the addition of STAT3 inhibitor WP1066 blocked PCB126-induced down-regulation of E-cadherin as well as up-regulation of N-cadherin and vimentin. Moreover, PCB126 exposure increased pyruvate kinase M2 (PKM2) expression and its nuclear translocation, whereas treatment with PKM2 shRNA suppressed the activation of STAT3/Snail1 signaling and the alternation of EMT-related molecules (E-cadherin, N-cadherin and vimentin). Furthermore, this study indicated estrogen receptor (ER) and aryl hydrocarbon receptor (AhR) were involved in PCB126-induced effects on PKM2, STAT3/Snail1 signaling and EMT by according treatment using ER inhibitor ICI and AhR shRNA. Notably, PCB126-increased reactive oxygen species (ROS) production via AhR is associated with activation of PKM2/STAT3/Snail1 cascades and contributes to EMT. Taken together, these results indicated that PCB126 promotes EMT process of HCC cells via PKM2/STAT3/Snail1 signaling which is mediated by ER and AhR.
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Affiliation(s)
- Li Song
- Institute of Biotechnology, Key Laboratory of Chemical Biology and Molecular Engineering of National Ministry of Education, Shanxi University, Taiyuan 030006, China
| | - Linlin Guo
- Institute of Biotechnology, Key Laboratory of Chemical Biology and Molecular Engineering of National Ministry of Education, Shanxi University, Taiyuan 030006, China
| | - Zhuoyu Li
- Institute of Biotechnology, Key Laboratory of Chemical Biology and Molecular Engineering of National Ministry of Education, Shanxi University, Taiyuan 030006, China; College of Life Science, Zhejiang Chinese Medical University, Hangzhou 310053, China.
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4
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Coactivation of the PI3K/Akt and ERK signaling pathways in PCB153-induced NF-κB activation and caspase inhibition. Toxicol Appl Pharmacol 2014; 277:270-8. [DOI: 10.1016/j.taap.2014.03.027] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2014] [Revised: 03/11/2014] [Accepted: 03/28/2014] [Indexed: 12/21/2022]
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5
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Shen H, Li M, Wang B, Lai IK, Robertson LW, Ludewig G. Dietary antioxidants (selenium and N-acetylcysteine) modulate paraoxonase 1 (PON1) in PCB 126-exposed rats. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2014; 21:6384-99. [PMID: 23644946 PMCID: PMC3769429 DOI: 10.1007/s11356-013-1690-1] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/11/2013] [Accepted: 03/26/2013] [Indexed: 05/10/2023]
Abstract
Environmental pollutants polychlorinated biphenyls (PCBs), especially dioxin-like PCBs, cause oxidative stress and associated toxic effects, including cancer and possibly atherosclerosis. We previously reported that PCB 126, the most potent dioxin-like PCB congener, not only decreases antioxidants such as hepatic selenium (Se), Se-dependent glutathione peroxidase, and glutathione (GSH) but also increases levels of the antiatherosclerosis enzyme paraoxonase 1 (PON1) in liver and serum. To probe the interconnection of these three antioxidant systems, Se, GSH, and PON1, we examined the influence of varying levels of dietary Se and N-acetylcysteine (NAC), a scavenger of reactive oxygen species (ROS) and precursor for GSH synthesis, on PON1 in the absence and presence of PCB 126 exposure. Male Sprague-Dawley rats, fed diets with differing Se levels (0.02, 0.2, or 2 ppm) or NAC (1%), were treated with a single intraperitoneal injection of corn oil or various doses of PCB 126 and euthanized 2 weeks later. PCB 126 significantly increased liver PON1 mRNA, protein level and activity, and serum PON1 activity in all dietary groups but did not consistently increase thiobarbituric acid levels (thiobarbituric acid reactive substances, TBARS), an indicator of lipid oxidation and oxidative stress, in liver or serum. Inadequate (high or low) dietary Se decreased baseline and PCB 126-induced aryl hydrocarbon receptor (AhR) expression but further increased PCB 126-induced cytochrome P450 1A1 (CYP1A1) expression, the enzyme believed to be the cause for PCB 126-induced oxidative stress. In addition, a significant inverse relationship was observed not only between dietary Se levels and PON1 mRNA and PON1 activity but also with TBARS levels in the liver, suggesting significant antioxidant protection from dietary Se. NAC lowered serum baseline TBARS levels in controls and increased serum PON1 activity but lowered liver PON1 activities in animals treated with 1 μmol/kg PCB 126, suggesting antioxidant activity by NAC primarily in serum. These results also show an unexpected predominantly inverse relationship between Se or NAC and PON1 during control and PCB 126 exposure conditions. These interactions should be further explored in the development of dietary protection regimens.
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Affiliation(s)
- Hua Shen
- Interdisciplinary Graduate Program in Human Toxicology, The University of Iowa, Iowa City, Iowa
| | - Miao Li
- Interdisciplinary Graduate Program in Human Toxicology, The University of Iowa, Iowa City, Iowa
| | - Bingxuan Wang
- Interdisciplinary Graduate Program in Human Toxicology, The University of Iowa, Iowa City, Iowa
| | - Ian K. Lai
- Interdisciplinary Graduate Program in Human Toxicology, The University of Iowa, Iowa City, Iowa
| | - Larry W. Robertson
- The University of Iowa Department of Occupational & Environmental Health, The University of Iowa, Iowa City, Iowa
- Interdisciplinary Graduate Program in Human Toxicology, The University of Iowa, Iowa City, Iowa
| | - Gabriele Ludewig
- The University of Iowa Department of Occupational & Environmental Health, The University of Iowa, Iowa City, Iowa
- Interdisciplinary Graduate Program in Human Toxicology, The University of Iowa, Iowa City, Iowa
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Kasaikina MV, Turanov AA, Avanesov A, Schweizer U, Seeher S, Bronson RT, Novoselov SN, Carlson BA, Hatfield DL, Gladyshev VN. Contrasting roles of dietary selenium and selenoproteins in chemically induced hepatocarcinogenesis. Carcinogenesis 2013; 34:1089-95. [PMID: 23389288 DOI: 10.1093/carcin/bgt011] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
Selenium (Se) has long been known for its cancer prevention properties, but the molecular basis remains unclear. The principal questions in assessing the effect of dietary Se in cancer are whether selenoproteins, small molecule selenocompounds, or both, are involved, and under which conditions and genotypes Se may be protective. In this study, we examined diethylnitrosamine-induced hepatocarcinogenesis in mice lacking a subset of selenoproteins due to expression of a mutant selenocysteine tRNA gene (Trsp (A37G) mice). To uncouple the effects of selenocompounds and selenoproteins, these animals were examined at several levels of dietary Se. Our analysis revealed that tumorigenesis in Trsp (A37G) mice maintained on the adequate Se diet was increased. However, in the control, wild-type mice, both Se deficiency and high Se levels protected against tumorigenesis. We further found that the Se-deficient diet induced severe neurological phenotypes in Trsp A37G mice. Surprisingly, a similar phenotype could be induced in these mice at high dietary Se intake. Overall, our results show a complex role of Se in chemically induced hepatocarcinogenesis, which involves interaction among selenoproteins, selenocompounds and toxins, and depends on genotype and background of the animals.
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Affiliation(s)
- Marina V Kasaikina
- Division of Genetics, Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, MA 02115, USA
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7
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N-acetylcysteine (NAC) diminishes the severity of PCB 126-induced fatty liver in male rodents. Toxicology 2012; 302:25-33. [PMID: 22824115 DOI: 10.1016/j.tox.2012.07.007] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2012] [Revised: 07/09/2012] [Accepted: 07/15/2012] [Indexed: 01/15/2023]
Abstract
Potent aryl hydrocarbon receptor agonists like PCB 126 (3,3',4,4',5-pentachlorobiphenyl) cause oxidative stress and liver pathology, including fatty liver. Our question was whether dietary supplementation with N-acetylcysteine (NAC), an antioxidant, can prevent these adverse changes. Male Sprague-Dawley rats were fed a standard AIN-93G diet (sufficient in cysteine) or a modified diet supplemented with 1.0% NAC. After one week, rats on each diet were exposed to 0, 1, or 5μmol/kg body weight PCB 126 by i.p. injection (6 rats per group) and euthanized two weeks later. PCB-treatment caused a dose-dependent reduction in growth, feed consumption, relative thymus weight, total glutathione and glutathione disulfide (GSSG), while relative liver weight, glutathione transferase activity and hepatic lipid content were dose-dependently increased with PCB dose. Histologic examination of liver tissue showed PCB 126-induced hepatocellular steatosis with dose dependent increase in lipid deposition and distribution. Dietary NAC resulted in a reduction in hepatocellular lipid in both PCB groups. This effect was confirmed by gravimetric analysis of extracted lipids. Expression of CD36, a scavenger receptor involved in regulating hepatic fatty acid uptake, was reduced with high dose PCB treatment but unaltered in PCB-treated rats on NAC-supplemented diet. These results demonstrate that NAC has a protective effect against hepatic lipid accumulation in rats exposed to PCB 126. The mechanism of this protective effect appears to be independent of NAC as a source of cysteine/precursor of glutathione.
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8
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Lai IK, Chai Y, Simmons D, Watson WH, Tan R, Haschek WM, Wang K, Wang B, Ludewig G, Robertson LW. Dietary selenium as a modulator of PCB 126-induced hepatotoxicity in male Sprague-Dawley rats. Toxicol Sci 2011; 124:202-14. [PMID: 21865291 DOI: 10.1093/toxsci/kfr215] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
Homeostasis of selenium (Se), a critical antioxidant incorporated into amino acids and enzymes, is disrupted by exposure to aryl hydrocarbon receptor (AhR) agonists. Here we examined the importance of dietary Se in preventing the toxicity of the most toxic polychlorinated biphenyl congener, 3,3',4,4',5-pentachlorobiphenyl (PCB 126), a potent AhR agonist. Male Sprague-Dawley rats were fed a modified AIN-93 diet with differing dietary Se levels (0.02, 0.2, and 2 ppm). Following 3 weeks of acclimatization, rats from each dietary group were given a single ip injection of corn oil (vehicle), 0.2, 1, or 5 μmol/kg body weight PCB 126, followed 2 weeks later by euthanasia. PCB exposure caused dose-dependent increases in liver weight and at the highest PCB 126 dose decreases in whole body weight gains. Hepatic cytochrome P-450 (CYP1A1) activity was significantly increased even at the lowest dose of PCB 126, indicating potent AhR activation. PCB exposure diminished hepatic Se levels in a dose-dependent manner, and this was accompanied by diminished Se-dependent glutathione peroxidase activity. Both these effects were partially mitigated by Se supplementation. Conversely, thioredoxin (Trx) reductase activity and Trx oxidation state, although significantly diminished in the lowest dietary Se groups, were not affected by PCB exposure. In addition, PCB 126-induced changes in hepatic copper, iron, manganese, and zinc were observed. These results demonstrate that supplemental dietary Se was not able to completely prevent the toxicity caused by PCB 126 but was able to increase moderately the levels of several key antioxidants, thereby maintaining them roughly at normal levels.
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Affiliation(s)
- Ian K Lai
- Interdisciplinary Graduate Program in Human Toxicology, College of Public Health, University of Iowa, Iowa City, Iowa 52242, USA
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9
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Glauert HP, Calfee-Mason K, Stemm DN, Tharappel JC, Spear BT. Dietary antioxidants in the prevention of hepatocarcinogenesis: a review. Mol Nutr Food Res 2010; 54:875-96. [PMID: 20512789 DOI: 10.1002/mnfr.200900482] [Citation(s) in RCA: 71] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
In this review, the role of dietary antioxidants in the prevention of hepatocarcinogenesis is examined. Both human and animal models are discussed. Vitamin C, vitamin E, and selenium are antioxidants that are essential in the human diet. A number of non-essential chemicals also contain antioxidant activity and are consumed in the human diet, mainly as plants or as supplements, including beta-carotene, ellagic acid, curcumin, lycopene, coenzyme Q(10), epigallocatechin gallate, N-acetyl cysteine, and resveratrol. Although some human and animal studies show protection against carcinogenesis with the consumption of higher amounts of antioxidants, many studies show no effect or an enhancement of carcinogenesis. Because of the conflicting results from these studies, it is difficult to make dietary recommendations as to whether consuming higher amounts of specific antioxidants will decrease the risk of developing hepatocellular carcinoma.
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Affiliation(s)
- Howard P Glauert
- Graduate Center for Nutritional Sciences, University of Kentucky, Lexington, KY 40506-0054, USA.
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10
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Lai I, Chai Y, Simmons D, Luthe G, Coleman MC, Spitz D, Haschek WM, Ludewig G, Robertson LW. Acute toxicity of 3,3',4,4',5-pentachlorobiphenyl (PCB 126) in male Sprague-Dawley rats: effects on hepatic oxidative stress, glutathione and metals status. ENVIRONMENT INTERNATIONAL 2010; 36:918-23. [PMID: 19969354 PMCID: PMC2891598 DOI: 10.1016/j.envint.2009.11.002] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/06/2009] [Revised: 10/18/2009] [Accepted: 11/12/2009] [Indexed: 05/02/2023]
Abstract
Although polychlorinated biphenyl (PCBs) production, and new uses for PCBs, was halted in the 1970s in the United States, PCBs continue to be used in closed systems and persist in the environment, accumulating in fatty tissues. PCBs are efficacious inducers of drug metabolism and may increase oxidative events and alter many other biochemical and morphologic parameters within cells and tissues. The goal of the present study was to evaluate the effects of a single, very low dose of PCB 126 (3,3',4,4',5-pentachlorobiphenyl), a coplanar, dioxin-like PCB congener and aryl hydrocarbon receptor (AhR) agonist, on redox status, metals homeostasis, antioxidant enzymes, and cellular morphology. To examine these parameters, male Sprague-Dawley rats were fed a purified AIN-93 basal diet containing 0.2 ppm selenium for two weeks, then administered a single i.p. injection of corn oil (5 ml/kg body weight) or 1µmol PCB 126/kg body weight (326µg/kg body weight) in corn oil. Rats were maintained on the diet for an additional two weeks before being euthanized. This dose of PCB 126 did not alter feed intake or growth, but significantly increased liver weight (42%) and hepatic microsomal cytochrome P-450 (CYP1A) enzyme activities (10-40-fold increase). Hepatic zinc, selenium, and glutathione levels were significantly decreased 15%, 30%, and 20%, respectively, by PCB 126. These changes were accompanied by a 60% decrease in selenium-dependent glutathione peroxidase activity. In contrast, hepatic copper levels were increased 40% by PCB 126. PCB 126-induced pathology was characterized by hepatocellular hypertrophy and mild steatosis in the liver and a mild decrease in cortical T-cells in the thymus. This controlled study in rats fed a purified diet shows that even a single, very low dose of PCB 126 that did not alter feed intake or growth, significantly perturbed redox and metals homeostasis and antioxidant and enzyme levels in rodent liver.
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Affiliation(s)
- Ian Lai
- Interdisciplinary Graduate Program in Human Toxicology, University of Iowa
- Department of Occupational & Environmental Health, University of Iowa
| | - Yingtao Chai
- University Hygienic Laboratory, University of Iowa
| | - Don Simmons
- University Hygienic Laboratory, University of Iowa
| | - Gregor Luthe
- Interdisciplinary Graduate Program in Human Toxicology, University of Iowa
- Department of Occupational & Environmental Health, University of Iowa
| | - Mitchell C. Coleman
- Free Radical and Radiation Biology Program, Department of Radiation Oncology, University of Iowa
| | - Douglas Spitz
- Interdisciplinary Graduate Program in Human Toxicology, University of Iowa
- Free Radical and Radiation Biology Program, Department of Radiation Oncology, University of Iowa
| | - Wanda M. Haschek
- Department of Pathobiology, University of Illinois, Urbana, IL 61802
| | - Gabriele Ludewig
- Interdisciplinary Graduate Program in Human Toxicology, University of Iowa
- Department of Occupational & Environmental Health, University of Iowa
| | - Larry W. Robertson
- Interdisciplinary Graduate Program in Human Toxicology, University of Iowa
- Department of Occupational & Environmental Health, University of Iowa
- Free Radical and Radiation Biology Program, Department of Radiation Oncology, University of Iowa
- Address Correspondence to Larry W. Robertson: Larry W. Robertson, Ph.D., M.P.H., Professor, Department of Occupational and Environmental Health, The University of Iowa, College of Public Health, 100 Oakdale Campus #219 IREH, Iowa City, Iowa 52242-5000, Phone: 319-335-4554, Fax: 319-335-4290,
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Tuzcu M, Sahin N, Ozercan I, Seren S, Sahin K, Kucuk O. The effects of selenium supplementation on the spontaneously occurring fibroid tumors of oviduct, 8-hydroxy-2'-deoxyguanosine levels, and heat shock protein 70 response in Japanese quail. Nutr Cancer 2010; 62:495-500. [PMID: 20432170 DOI: 10.1080/01635580903441303] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Oxidative stress is known to be an important contributing factor in many chronic diseases. Spontaneously occurring benign oviduct leiomyomas are common tumors of the Japanese quail (Coturnix coturnix japonica), which makes it a good animal model for screening potential agents for testing in the prevention and treatment of human myoma uteri. Since dietary intake of selenium has been associated with a reduced risk of a variety of human cancers, we investigated the effects of selenium supplementation on the development of leiomyomas in the Japanese quail. Potential mechanisms of action of selenium include its antioxidant properties and modulation of heat shock protein 70 (Hsp70); therefore, we measured levels of 8-hydroxy-2'-deoxyguanosine (8-OHdG), 8-isoprostane levels, and Hsp70 expression in tissue specimens obtained from the quails. One hundred and eighty quails (8 mo old) were assigned to 3 treatment groups consisting of 60 birds in each group. Birds were fed either a basal diet containing 0.048 mg Se per kg or the basal diet supplemented with 0.2 mg or 0.4 mg of selenium (Selenomax, yeast-bound l-selenomethionine, 60%) per kg of diet. The animals were sacrificed after 250 days, and the tumors were identified. Selenium supplementation did not affect the number of leiomyomas as compared to control subjects (P > 0.05). However, the tumors in selenium fed birds were smaller than those found in control birds (P = 0.01). Serum Se increased (P = 0.01), whereas MDA and 8-isoprostane, 8-OHdG concentrations decreased (P = 0.01) with selenium supplementation (P = 0.01). Selenium supplementation decreased Hsp70 in the tissue of birds. The results indicate that dietary supplementation with selenium reduces the size of spontaneously occurring leiomyoma of the oviduct in the Japanese quail.
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Affiliation(s)
- Mehmet Tuzcu
- Faculty of Science, Firat University, Elazig, Turkey
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12
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Effect of antioxidant phytochemicals on the hepatic tumor promoting activity of 3,3',4,4'-tetrachlorobiphenyl (PCB-77). Food Chem Toxicol 2008; 46:3467-74. [PMID: 18796325 DOI: 10.1016/j.fct.2008.08.023] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2008] [Revised: 08/08/2008] [Accepted: 08/22/2008] [Indexed: 12/12/2022]
Abstract
Polychlorinated biphenyls (PCBs) have promoting activity in the liver, which may be brought about in part by the induction of oxidative stress. In this study we examined the effects of several antioxidant phytochemicals on the tumor promoting activity of 3,3',4'4-tetrachlorobiphenyl (PCB-77). Female Sprague Dawley rats were first injected with diethylnitrosamine (DEN, 150 mg/kg) and one week later the rats were fed an AIN-93 based purified diet or the same diet containing ellagic acid (0.4%), beta-carotene (0.5%), curcumin (0.5%), N-acetyl cysteine (NAC, 1.0%), coenzyme CoQ10 (CoQ10, 0.4%), resveratrol (0.005%), lycopene (10% as Lycovit, which contains 10% lycopene), or a tea extract (1%, containing 16.5% epigallocatechin-3-gallate [EGCG] and 33.4% total catechins). Rats were fed the diets for the remainder of the study. After three weeks, 2/3 of the control rats and all of the antioxidant diet-fed rats were injected i.p. with PCB-77 (300 micromol/kg) every other week for four injections. All rats were euthanized ten days after the last PCB injection. The rats that received PCB-77 alone showed an increase in the number and size of placental glutathione S-transferase (PGST)-positive foci in the liver. Lycopene significantly decreased the number of foci, while curcumin and CoQ10 decreased the size of the foci. In contrast, ellagic acid increased the number but decreased the size of the foci. All of the other phytochemicals showed only slight or no effects. Compared with the PCB-77 group, CoQ10 increased cell proliferation in normal hepatocytes, whereas the other antioxidants had no effect in either normal or PGST-positive hepatocytes. These findings show that none of the antioxidant phytochemicals produced a clear decrease in the promoting activity of PCB-77.
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