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    Antioxidative effects of novel synthetic organoselenium compound in rat lung and kidney
    (ACADEMIC PRESS INC ELSEVIER SCIENCE, 2009) Talas, Zeliha Selamoglu; Ozdemir, Ilknur; Yilmaz, Ismet; Gok, Yetkin
    The effects of environmental chemicals, drugs, and physical agents on the developing lung and kidney are influenced by the state of development and maturation. Selenium is an essential element with physiological nonenzymatic antioxidant properties. Therefore, we undertook the present study to evaluate the antioxidant potential of the novel synthetic organoselenium compounds (Se I and Se II). In this study, adult female Wistar rats were treated with DMBA and the novel organoselenium compounds [1-isopropyl-3-methylbenzimidazole-2-selenone (Se I) and 1,3-di-p-methoxybenzylpyrimidine-2-selenone (Se II)] in the determined doses. The protective effects of novel synthetic organoselenium compounds (Se I and Se II) against DMBA-induced changes in levels of some [superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), and glutathione reductase (GR) activities and total glutathione (GSH), malonedialdehyde (MDA)] parameters in rat lung and kidney were investigated. As a result, it was found that both Se I and Se II had provided the antioxidant effects against DMBA-induced oxidative stress in rat lung and kidney and lipid peroxidation had also been decreased by these organoselenium compounds. (c) 2007 Elsevier Inc. All rights reserved.
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    CHANGES IN TYROSINE HYDROXYLASE ACTIVITY, ADRENOMEDULLIN (ADM) AND TOTAL RNA LEVELS BY TREATMENT OF ORGANOSELENIUM COMPOUNDS IN RAT HYPOTHALAMUS EXPOSED TO 7,12-DIMETHYLBENZANTHRACENE (DMBA)
    (PARLAR SCIENTIFIC PUBLICATIONS (P S P), 2010) Ozdemir, Ilknur; Talas, Zeliha Selamoglu; Gok, Yetkin; Ates, Burhan; Yilmaz, Ismet
    The effects of synthetic organoselenium compounds (Se I and Se II) on the activity of tyrosine hydroxylase (TH), the rate-limiting enzyme in catecholamine synthesis as well as adrenomedullin (ADM) and total RNA levels were determined in the hypothalamus of adult rats exposed to DMBA (7,12-dimethylbenz[a]anthracene). DMBA, an organic environmental pollutant, is a polycyclic aromatic hydrocarbon that can induce a range of toxic effects and stress in rats. Selenium is an essential trace element, which interacts with antioxidants, and has anticancer and antihypertensive properties. TH is an aromatic amino acid hydroxylase whose activity is elevated in response to a range of stress inducers. TH activity is normally regulated by negative feedback in catecholamine biosynthesis. ADM is an abundantly present peptide in a broad range of normal tissues including adrenal medulla, lungs, kidneys and brain. Plasma ADM levels are elevated in a number of diseases including essential hyptertension and chronic renal failure. The antioxidant properties of ADM offer protection against organ damage induced by high blood pressure, ischemia and aging. DMBA treatment increased the TH activity and ADM level in the hypothalamus. These increases were found to be inhibited by Se I and Se II treatments. These studies demonstrate that synthetic organoselenium compounds can suppress DMBA-induced stress-related changes in the rat hypothalamus. Therefore, the antioxidant and antihypertensive effects of Se I and Se II may have important effects in the maintainance of homeostasis.
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    Modulating effects of selenium in adrenal medulla of rats exposed to 7,12-dimethylbenz[a]anthracene
    (SAGE PUBLICATIONS INC, 2013) Talas, Zeliha Selamoglu; Ozdemir, Ilknur; Ates, Burhan; Gok, Yetkin; Yilmaz, Ismet
    Objective: The aim of this study was to evaluate the chemopreventive potential of organoselenium compounds (Se I and Se II) in the well-established rat model treated with 7,12-dimethylbenz[a]anthracene (DMBA), by monitoring the extent of tyrosine hydroxylase (TH) activity, adrenomedullin (ADM) level and total RNA level in adrenal medulla. Organic pollutants are the most important environmental factor for the biologic systems. DMBA exposure appears to be associated with a number of physiological disease processes. Methods: The effects of Se I and Se II compounds were investigated on TH activity, ADM and total RNA levels in adrenal medulla of rats exposed to DMBA. Results: TH activity, ADM and total RNA levels were found to be increased significantly due to the effect of DMBA (p < 0.05). This increase was restricted in the Se I-and Se II-treated groups (p < 0.05). Conclusion: The present data showed that the organoselenium compounds may have important effects in the maintainance of homeostasis against stress induced by DMBA.
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    Role of selenium compounds on tyrosine hydroxylase activity, adrenomedullin and total RNA levels in hearts of rats
    (ELSEVIER SCIENCE BV, 2010) Talas, Zeliha Selamoglu; Ozdemir, Ilknur; Gok, Yetkin; Ates, Burhan; Yilmaz, Ismet
    Synthetic organoselenium compounds can be tailored to achieve greater chemopreventive efficacy with minimal toxic side effects by structural modifications. Two organoselenium compounds (Se I and Se II) were synthesized and evaluated for their antihypertensive and therapeutic properties by adrenomedullin (ADM) levels and tyrosine hydroxylase (TH) activity assays in rat heart tissue. 7,12-Dimethylbenz[a]anthracene (DMBA) is known to generate DNA-reactive species during their metabolism, which may enhance oxidative stress in cells. TH is thought to be a rate-limiting enzyme in the biosynthesis of catecholamines. ADM, a potent endogenous vasodilating and natriuretic peptide, may play an important role in the pathophysiology of chronic heart failure. The effects of Se I and Se II were investigated on TH activity, ADM and total RNA levels in the hearts of albino Wistar rats. TH activity was found to be increased significantly by the effect of DMBA (P < 0.05). This increase was restricted in the Se I and Se H treated groups. ADM level was found to be decreased insignificantly by the effect of DMBA (P > 0.05). Total RNA level was found to be decreased significantly by the effect of DMBA (P < 0.05). This study demonstrates that synthetic organoselenium compounds can regulate DMBA-induced stress related changes in rat heart. (C) 2009 Elsevier B.V. All rights reserved.
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    Role of Synthesized Organoselenium Compounds on Protection of Rat Erythrocytes from DMBA-Induced Oxidative Stress
    (HUMANA PRESS INC, 2009) Talas, Zeliha Selamoglu; Yilmaz, Ismet; Ozdemir, Ilknur; Ates, Burhan; Gok, Yetkin; Cetinkaya, Bekir
    Formation of free radicals is not limited to normal cellular process but also occur upon exposure to certain chemicals (polycyclic aromatic hydrocarbon, cadmium, lead, etc.), cigarette smoke, radiation, and high-fat diet. Free-radical damage is an important factor in many pathological and toxicological processes. Selenium, an essential micronutrient, is a associated with antioxidant functions, physiological defense mechanisms against different diseases including several types of cancers. Search for new selenium compounds with more chemopreventive activities and less toxicities are in progress. In addition, there has been a growing interest in the synthesis of organoselenium compounds with respect to their use in enzymology and bioorganic chemistry. In the present study, adult female Wistar rats were treated with 7,12-dimethylbenz[a]anthracene (DMBA) and the organoselenium compounds [1-isopropyl-3-methylbenzimidazole-2-selenone (Se I) and 1, 3-di-p-methoxybenzylpyrimidine-2-selenone (Se II)] in determined doses. The protective effects of synthetic organoselenium compounds (Se I and Se II) against DMBA-induced changes in antioxidant enzyme (superoxide dismutase, glutathione peroxidase (GSH-Px), catalase (CAT), glutathione reductase (GR)) activities, total GSH, and malondialdehyde (MDA) levels of rat erythrocyte were investigated. The DMBA-treated group exhibited significant decreases in the levels of erythrocyte GSH-Px, CAT, and GR activities, an increase in MDA levels, and a decrease in total GSH level compared to the control. Se I and Se II fully or partially restored enzyme activity. Lipid peroxidation was also decreased in Se-I- and Se-II-treated groups.
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    Synthesis, antioxidant and anti-microbial properties of two organoselenium compounds
    (UNIV KARACHI, 2015) Talas, Zeliha Selamoglu; Gok, Yetkin; Ozdemir, Ilknur; Ates, Burhan; Gunal, Selami; Yilmaz, Ismet
    The aim of this study is synthesis of two different series of organoselenium compounds and available in vitro antioxidant and antimicrobial properties of thee synthetic compounds. The synthetic compounds were identified by H-1-NMR (300 MHz), C-13-NMR (75.5 MHz), FT-IR spectroscopic techniques and micro analysis. Antioxidant properties of two synthetic organoselenium compounds were determined by 1,1- dipheny1-2-picrylhydrazyl (DPPH) radical method, reducing power assay and beta-carotene bleaching method as in vitro. Antimicrobial effects of samples were assessed by the agar dilution procedure and using gram positive and gram-negative bacteria and yeast strains. Although 1,3-di-pmethoxybenzylpyrimidine-2-selenone showed better antiradical activity in DPPH test and higher protective activity on beta-carotene, 1-isopropyl-3-methylbenzimidazole-2-selenone was found to be better in reducing power and antimicrobial activity.
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    The effects of synthetic organoselenium compounds on nitric oxide in DMBA - induced rat liver
    (TRIVENI ENTERPRISES, 2009) Talas, Zeliha Selamoglu; Bayraktar, Nihayet; Ozdemir, Ilknur; Gok, Yetkin; Yilmaz, Ismet
    DMBA (7,12-dimethylbenz[a]anthracene) is known to generate DNA-reactive species during their metabolism, which may enhance oxidative stress in cells. Since selenium is known as a non-enzymic antioxidant, health problems induced by many environmental pollutants, have stimulated the evaluation of relative antioxidant potential of selenium and synthetic organoselenium compounds. Therefore, we aimed to evaluate chemopreventive potential of synthetic organoselenium compounds by monitoring level of liver nitric oxide. In this study, adult female Wistar rats were treated with DMBA and the novel organoselenium compounds (Se I) and (Se II) in the determined doses. DMBA-induced in rats, the effects of organoselenium compounds on nitric oxide levels in rat liver was studied. In this study, it has been observed a statistically significant increase in (Nitric Oxide) levels for the liver of rat exposed to DMBA (p<0.05). However with administration of Se I and Se II there was a statistically significant decrease in NO levels (p<0.05). The ability of the organoselenium compounds to prevent oxidative damage induced by DMBA in rat livers was rationalized. Protection against nitric oxide measured in Se I and Sell treated groups were provided by synthesized organoselenium compounds. Se I and Sell both provided chemoprevention against DMBA-induced oxidative stress in rat liver.
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    The effects of synthetic organoselenium compounds on nitric oxide in DMBA - Induced rat liver
    (Triveni Enterprises, 2009) Talas, Zeliha Selamoglu; Bayraktar, Nihayet; Ozdemir, Ilknur; Gok, Yetkin; Yilmaz, Ismet
    DMBA (7,12-dimethylbenz[a]anthracene) is known to generate DNA-reactive species during their metabolism, which may enhance oxidative stress in cells. Since selenium is known as a non-enzymic antioxidant, health problems induced by many environmental pollutants, have stimulated the evaluation of relative antioxidant potential of selenium and synthetic organoselenium compounds. Therefore, we aimed to evaluate chemopreventive potential of synthetic organoselenium compounds by monitoring level of liver nitric oxide. In this study, adult female Wistar rats were treated with DMBA and the novel organoselenium compounds (Se I) and (Se II) in the determined doses. DMBA-induced in rats, the effects of organoselenium compounds on nitric oxide levels in rat liver was studied. In this study, it has been observed a statistically significant increase in (Nitric Oxide) levels for the liver of rat exposed to DMBA (p<0.05). However with administration of Se I and Se II there was a statistically significant decrease in NO levels (p<0.05). The ability of the organoselenium compounds to prevent oxidative damage induced by DMBA in rat livers was rationalized. Protection against nitric oxide measured in Se I and Se II treated groups were provided by synthesized organoselenium compounds. Se I and Se II both provided chemoprevention against DMBA-induced oxidative stress in rat liver. © Triveni Enterprises.
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    The investigation of the antioxidative properties of the novel synthetic organoselenium compounds in some rat tissues
    (SAGE PUBLICATIONS LTD, 2008) Talas, Zeliha Selamoglu; Ozdemir, Ilknur; Yilmaz, Ismet; Gok, Yetkin; Orun, Ibrahim
    DMBA (7,12-dimethylbenz[a]anthracene) is a polycyclic aromatic hydrocarbon (PAH) known to cause tumors in rats. Selenium is an essential element with physiological nonenzymatic antioxidant properties. Because of the health problems induced by many environmental pollutants, many efforts have been undertaken in evaluating the relative antioxidant potential of selenium and synthetic organoselenium compounds. In this study, adult female Wistar rats were treated with DMBA and the novel organoselenium compounds (1-isopropyl-3-methylbenzimidazole-2-selenone [Sel] and 1,3di-p-methoxybenzylpyrimidine-2-selenone [Sell]) in the determined doses. The protective effects of novel synthetic organoselenium compounds (Sel and Sell) against DMBA-induced changes in superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), and glutathione reductase (GR) activities and total glutathione (GSH) and malonedialdehyde (MDA) levels of rat heart and brain were investigated. It was determined that Sel and Sell fully or partially restored enzyme activity. It was also found that lipid peroxidation was also decreased in Sel and Sell treated groups. Consequently, it was determined that novel synthetic organoselenium compounds (Sel and Sell) provided protection of antioxidant activity, and protection against lipid peroxidation measured as MDA in Sel and Sell treated groups was provided by novel synthesized organoselenium compounds. The ability of the organoselenium compounds to prevent oxidative damage induced by DMBA in rats was rationalized.