Yazar "Talas, Zeliha Selamoglu" seçeneğine göre listele
Listeleniyor 1 - 15 / 15
Sayfa Başına Sonuç
Sıralama seçenekleri
Öğe 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, YetkinThe 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.Öğe Antioxidative role of selenium against the toxic effect of heavy metals (Cd+2 Cr+3 on liver of rainbow trout (Oncorhynchus mykiss Walbaum 1792)(Springer, 2008) Talas, Zeliha Selamoglu; Orun, Ibrahim; Ozdemir, Ilknur; Erdogan, Kenan; Alkan, Aysel; Yilmaz, IsmetThe main purpose of this study is to discuss the effect of Cd+2, Cr+3 and Se metals on biochemical parameters in liver tissue of Oncorhynchus mykiss. The rainbow trout were exposed to heavy metal stress ( Cd+2, Cr+3) at 2 ppm dosage. The present study was undertaken to determine the protective effect of selenium treatment at the same dosage ( 2 ppm) on some biochemical parameters. The activity of catalase ( CAT), glutathione peroxidase ( GSH-Px), superoxide dismutase ( SOD) and the changes in levels of malondialdehyde ( MDA) from biochemical parameters were determined in liver tissue of the fish groups exposed to heavy metals, especially for the selenium-applied groups. Results of this study showed that the activities of CAT, GSH-Px and SOD in the tissues of fish exposed to the stress of Cd+2 and Cr+3 were significantly lower than the control groups ( P < 0.05). Meanwhile, the closer values to the control groups were obtained in selenium-added groups ( Cr+3 + Se+4, Cd+2 + Se+4). For the level of MDA, the last production of lipid peroxidation showed increases ( P < 0.05) in the groups exposed to the metal stress, whereas significant decreases were obtained in selenium-applied groups. The result of the statistical evaluation showed that the negative effects occurring in the biochemical parameters of the applied groups exposed to the toxicity of heavy metal were significantly eliminated ( P < 0.05) as a result of selenium treatment.Öğe Antioxidative role of selenium on some tissues of (Cd2+, Cr3+)-induced rainbow trout(Academic Press Inc Elsevier Science, 2008) Orun, Ibrahim; Talas, Zeliha Selamoglu; Ozdemir, IlKnur; Alkan, Aysel; Erdogan, KenanChemical toxic pollutants (especially heavy metals) are important sources of reactive oxygen species (ROS) in biological systems. Membrane phospholipids of aerobic organisms are continually subjected to oxidant challenges from endogenous and exogenous sources, while peroxidized membranes and lipid peroxidation products represent constant threats to aerobic cells. The primary antioxidant protection against free radical and ROS is provided by the enzymes glutathione peroxidase (GSH-Px), superoxide dismutase (SOD) and catalase (CAT), respectively. The trace element selenium has been implicated in chemo-prevention and drug-resistance through reduction of oxidative stress. Selenium could prevent damage to the unsaturated fatty acid Of subcellular membranes by lipid peroxidation induced by free radicals. The results reported here show that sodium selenite has an important contribution to antioxidative defense for the spleen and heart of rainbow trout. The ability of sodium selenite to prevent the oxidative stress induced by heavy metals (Cd2+, Cr3+) in fish was rationalized. (C) 2007 Elsevier Inc. All rights reserved.Öğe 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, IsmetThe 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.Öğe Effects of sodium selenite on some biochemical and hematological parameters of rainbow trout (Oncorhynchus mykiss Walbaum, 1792) exposed to Pb2+ and Cu2+(Springer, 2008) Ates, Burhan; Orun, Ibrahim; Talas, Zeliha Selamoglu; Durmaz, Gokhan; Yilmaz, IsmetThis study was carried out to understand the preventive effect of selenium (Se4+) on heavy metal stress induced by lead and copper in rainbow trout (Oncorhynchus mykiss). Variation in glutathione peroxidase (Se-GSH-Px) and superoxide dismutase (SOD) activity, and in malondialdehyde (MDA) levels in liver, spleen, heart, and brain tissues of rainbow trout after 72 h of exposure to Pb2+ and Cu2+ were investigated in the presence and absence of Se4+. In the presence of Se4+, Se-GSH-Px activity and SOD activity were found to be higher and MDA levels were lower compared with in its absence. Hematological parameters were also determined and it has been observed that total leukocyte count (WBC), mean cell volume (MCV), and mean cell hemoglobin (MCH) were increased and erythrocyte number (RBC), hemoglobin (Hb), and hematocrit value (Hct; P < 0.05) were decreased in fish exposed to heavy metals in the absence of selenium. Selenium presence recovered hematological parameters to normal levels. In the light of our findings, it could be stated that Pb2+ and Cu2+ lead to dramatic changes in biochemical and hematological parameters and selenium caused these parameters to converge to control levels when it was administered concurrently with these heavy metals.Öğe 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, IsmetDMBA (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.Öğe 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, IbrahimDMBA (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.Öğe MODULATING EFFECT OF SELENIUM ON GILLS OF FISH EXPOSED TO HEAVY METALS(Parlar Scientific Publications (P S P), 2011) Orun, Ibrahim; Talas, Zeliha Selamoglu; Alkan, AyselThe present study was performed to understand the preventive effect of selenium (Se4+) on heavy metal stress induced by Cd2+ and Cr3+ in rainbow trout. Changes in glutathione peroxidase (GSH-Px), catalase (CAT) and superoxide dismutase (SOD) activity, and in malondialdehyde (MDA) level in gill tissue of rainbow trout after 7 days of exposure to Cd2+ and Cr3+ were investigated in the presence and absence of Se4+. Heavy metals treated groups exhibited significant decreases (P<0.05) in GSH-Px, CAT, SOD activities of gill, and an increase (P<0.05) in MDA levels, compared to the control. In the presence of Se4+, GSH-Px activity and SOD activity were found to be higher and MDA levels were lower compared with in its absence. In the light of our findings, it could be stated that Cd2+ and Cr3+ lead to dramatic changes in biochemical parameters and selenium caused these parameters to converge to control levels when it was administered concurrently with these heavy metals. Selenium fully or partially restored enzyme activities. Lipid peroxidation was also decreased in selenium treated groups.Öğe 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, IsmetObjective: 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.Öğe Role of propolis on biochemical parameters in kidney and heart tissues against L-NAME induced oxidative injury in rats(Taylor & Francis Inc, 2014) Talas, Zeliha Selamoglu; Ozdemir, Ilknur; Ciftci, Osman; Cakir, Oguz; Gulhan, Mehmet Fuat; Pasaoglu, Oguz MuratNitric oxide (NO), produced by endothelial NO synthase, is recognised as a central antiinflammatory and antiatherogenic principle in the vasculature. Epidemiological and clinical studies have demonstrated that a growing list of natural products, as components of the daily diet or phytomedical preparations, may improve vascular function by enhancing NO bioavailability. In this article, we investigated antioxidant effects of propolis on biochemical parameters in kidney and heart tissues of acute NO synthase inhibited rats by N-omega-nitro-L-arginine methyl ester (L-NAME). There was increase (p < 0.001) in the activities of catalase and malondialdehyde levels in the L-NAME treatment groups when compared with control rats, but NO levels were decreased in both kidney and heart tissues. There were statistically significant changes (p < 0.001) in these parameters of L-NAME + propolis treated rats as compared with L-NAME-treated group. In summary, propolis may influence endothelial NO production.Öğe Role of Propolis on Oxidative Stress in Fish Brain(Iran Univ Medical Sciences, 2013) Kakoolaki, Shapour; Talas, Zeliha Selamoglu; Cakir, Oguz; Ciftci, Osman; Ozdemir, IlknurIntroduction: Cypermethrin causes its neurotoxic effect through voltage-dependent sodium channels and integral protein ATPases in the neuronal membrane. Brain and nerve damage are often associated with low residual level of pesticides. In vitro and in vivo studies have also shown that pesticides cause free radical-mediated tissue damage in brain. Propolis has antioxidant properties. The main chemical classes found in propolis are flavonoids and phenolics. Bioflavonoids are antioxidant molecules that play important roles in scavenging free radicals, which are produced in neurodegenerative diseases and aging. Methods: To determine the protective role of propolis, rainbow trouts were treated with cypermethrin, followed by biochemical analyses of brain tissue. Fish were divided into four groups: control, propolis-treated, cypermethrin-treated, and cypermethrin+propolis-treated. Results: In fish brains, catalase (CAT) activity decreased (P=0.001) and malondialdehyde (MDA) level increased (P=0.001) in cypermethrin-treated group compared to control group. In cypermethrin+propolis-treated group CAT activity increased (P=0.001) and MDA level decreased (P=0.001) compared to cypermethrin group. Discussion: The results demonstrated that the negative effects, observed as a result of cypermethrin treatment, could be reversed by adding supplementary propolis. Propolis may improve some biochemical markers associated with oxidative stress in fish brain, after exposure to cypermethrin.Öğe Role of Propolis on Tyrosine Hydroxylase Activity and Blood Pressure in Nitric Oxide Synthase-Inhibited Hypertensive Rats(Taylor & Francis Inc, 2012) Gogebakan, Ayse; Talas, Zeliha Selamoglu; Ozdemir, Ilknur; Sahna, EnginReduction in the synthesis or bioavailability of nitric oxide plays a significant role in the development of hypertension. Propolis is a resinous product collected by honeybees from various plant sources. Tyrosine hydroxylase (TH) is the rate-limiting enzyme in the biosynthesis of catecholamines. The aim of this study was to examine the effect of propolis on blood pressure (BP), TH, and total RNA levels in the adrenal medulla, heart, and hypothalamus tissues in chronic nitric oxide synthase (NOS)-inhibited rats by N-w-nitro-L-arginine methyl ester (L-NAME). Rats received NOS inhibitor (L-NAME) for 15 days to produce hypertension and propolis for the last 5 days. TH activity and total RNA levels significantly increased in adrenal medulla, heart, and hypothalamus tissues in L-NAME-treated groups (P < .05). TH activity and total RNA levels of L-NAME+propolis-treated rats reduced (P < .05) compared with L-NAME-treated groups. TH activity in propolis-treated rats was reduced to the control values. L-NAME led to a significant increase in BP compared with the control group. Propolis administration to L-NAME-treated rats reduced BP but this was not statistically significant compared to L-NAME-treated groups. These results suggest that propolis decreases TH activity in NOS-inhibited hypertensive rats and thereby may modulate the synthesis of catecholamine and BP.Öğe Role of selenium compounds on tyrosine hydroxylase activity, adrenomedullin and total RNA levels in hearts of rats(Elsevier, 2010) Talas, Zeliha Selamoglu; Ozdemir, Ilknur; Gok, Yetkin; Ates, Burhan; Yilmaz, IsmetSynthetic 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.Öğe Role of Synthesized Organoselenium Compounds on Protection of Rat Erythrocytes from DMBA-Induced Oxidative Stress(Springernature, 2009) Talas, Zeliha Selamoglu; Yilmaz, Ismet; Ozdemir, Ilknur; Ates, Burhan; Gok, Yetkin; Cetinkaya, BekirFormation 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.Öğe 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, IsmetThe 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.
