Yusuf Kalender
Gazi University
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Food and Chemical Toxicology | 2009
Fatma Gokce Uzun; Suna Kalender; Dilek Durak; Filiz Demir; Yusuf Kalender
Sexually mature male Wistar rats (weighing 300-320 g and each group 6 animals) were given malathion (27 mg/kg; 1/50 of the LD(50) for an oral dose) and/or vitamin C (200mg/kg)+vitamin E (200mg/kg) daily via gavage for 4 weeks. The sperm counts, sperm motility, sperm morphology, FSH, LH, and testosterone levels, and histopathological changes in the testes of these rats, were investigated at the end of the 4th week. By the end of 4th week, rats given malathion alone, or in combination with vitamins C and E, had significantly lower sperm counts and sperm motility, and significantly higher abnormal sperm numbers, than the untreated control rats. The rats given malathion alone or in combination with vitamins also had significantly lower plasma FSH, LH and testosterone levels than the control rats. Co-treatment of malathion-exposed rats with vitamins E and C had a protective effect on sperm counts, sperm motility and abnormal sperm numbers, but not on plasma FSH, LH and testosterone levels. Light microscopic investigations revealed that 4 weeks of malathion exposure was associated with necrosis and edema in the seminiferous tubules and interstitial tissues. Degenerative changes in the seminiferous tubules were also observed in the rats which received malathion and supplemented with vitamins C and E, but milder histopathological changes were observed in the interstitial tissues. Thus, it appears that vitamins C and E ameliorate malathion testicular toxicity but are not completely protective.
Environmental Toxicology and Pharmacology | 2006
Yusuf Kalender; Meltem Uzunhisarcikli; Ayse Ogutcu; Fatma Açikgoz; Suna Kalender
Diazinon (DZN) is an organophosphate insecticide has been used in agriculture and domestic for several years. Vitamin E (200mg/kg, twice a week), diazinon (10mg/kg, per day) and Vitamin E (200mg/kg, twice a week)+diazinon (10mg/kg, per day) combination were given to rats orally via gavage for 7 weeks. Pseudocholinesterase in serum and haematological indices were investigated at the end of the 1st, 4th and 7th weeks comparatively with control group. At the end of 1st, 4th and 7th weeks, statistically significant decrease of pseudocholinesterase activity in serum were detected when diazinon- and Vitamin E+diazinon-treated groups compared to control group. When diazinon- and Vitamin E+diazinon-treated groups were compared to each other there were no significant changes. When diazinon-treated group was compared to control group, body weight decreased significantly at the end of the 4th and 7th weeks. It was observed that at the end of 1st, 4th and 7th weeks, there was a statistically significance in haematological indices except mean corpuscular hemoglobin (MCH) when diazinon-treated group was compared to control group. At the end of 1st week increase of thrombocyte, at the end of the 4th week increase of hemoglobin and thrombocyte and at the end of the 7th week increase of red blood cell (RBC), hemoglobin, hematocrit, mean corpuscular hemoglobin concentration (MCHC) and thrombocyte were observed statistically significant when Vitamin E+diazinon treated group was compared with diazinon treated group. According to the present study, we conclude that Vitamin E reduces diazinon toxicity, but it does not protect completely.
Food and Chemical Toxicology | 2010
Suna Kalender; Fatma Gokce Uzun; Dilek Durak; Filiz Demir; Yusuf Kalender
Mature male Wistar rats (weighing 300-320 g and each group six animals) were given malathion (27 mg/kg; 1/50 of the LD50 for an oral dose), vitamin C (200 mg/kg)+vitamin E (200 mg/kg), or both daily via gavage for 4 weeks. At the end of the fourth week, the malathion-treated group and the malathion plus vitamin-treated group both had significantly higher white blood cell (WBC) and thrombocyte counts than the control group. Compared to the control group, the two groups also had significantly higher serum total cholesterol, alkaline phosphatase (ALP), alanine aminotransferase (ALT), aspartate aminotransferase (AST), and lactate dehydrogenase (LDH) levels, and significantly lower triglyceride and very low density lipoprotein (VLDL) levels. The malathion-treated rats also had significantly lower serum total protein and albumin levels, but the malathion plus vitamin-treated group did not differ from the control group in terms of these parameters. Moreover, concomitant vitamin treatment significantly normalized, at least partially, all of the other hematological and biochemical parameters that were altered by malathion. Light microscopic analyses revealed that both the malathion-treated and malathion plus vitamin-treated groups exhibited histopathological changes in liver tissues, although some pathological features were only observed in the malathion-treated group. Thus, vitamins C and E can reduce malathion hepatotoxicity, although the degree of protection they provide is limited.
Environmental Toxicology and Pharmacology | 2008
Ayse Ogutcu; Zekiye Suludere; Yusuf Kalender
Dichlorvos is an organophosphate insecticide that is widely used in pest control. Vitamin C (200mg/kg)+vitamin E (200mg/kg), dichlorvos (1.6mg/kg), or a combination of vitamin C (200mg/kg)+vitamin E (200mg/kg)+dichlorvos (1.6mg/kg) was given to rats via oral gavage for 7 weeks. When rats of the dichlorvos-treated group and the vitamins+dichlorvos-treated group were compared with the control group, body weights were decreased and liver weights were increased significantly at the end of the 4th and 7th week. Serum total protein, albumin, triglyceride, low density lipoprotein-cholesterol (VLDL-cholesterol) levels were decreased, and serum alkaline phosphatase (ALP), alanine aminotransferase (ALT), aspartate aminotransferase (AST), γ-glutamyl-transferase (GGT), lactate dehydrogenase (LDH), and total cholesterol levels were increased significantly at the end of the 4th and 7th week in the dichlorvos- and vitamins+dichlorvos-treated rats. There was a statistically significant difference for all biochemical parameters when the vitamins+dichlorvos-treated group was compared with the dichlorvos-treated group at the end of the 4th and 7th week. In an electron microscopic investigation, swelling of mitochondria and dilatation of endoplasmic reticulum were observed in liver cells of the dichlorvos- and vitamins+dichlorvos-treated rats at the end of the 4th and 7th week. As a result, vitamins C and E reduced dichlorvos hepatotoxicity, but vitamins C and E did not confer complete protection.
Environmental Toxicology and Pharmacology | 2012
Yusuf Kalender; Sinan Kaya; Dilek Durak; Fatma Gokce Uzun; Filiz Demir
Mature male Wistar rats were given chlorpyrifos (5.4 mg/kg, 1/25 of the oral LD(50)), catechin (20 mg/kg),quercetin (20 mg/kg), catechin plus chlorpyrifos, and quercetin plus chlorpyrifos daily via gavage for four weeks. No statistical differences were found in the catechin-only and quercetin-only groups compared with the control group. By the end of the fourth week, chlorpyrifos alone increased the levels of malondialdehyde (MDA), superoxide dismutase (SOD), catalase (CAT), while decreased glutathione peroxidase (GPx) and glutathione-S-transferase (GST) activities compared with the control group in rat testis tissues. In the catechin-plus-chlorpyrifos and quercetin-plus-chlorpyrifos groups, there were statistically significantly decreased MDA levels, SOD and CAT activities, while increased GPx and GST activities compared with the chlorpyrifos-only group. Light microscopic analyses revealed that chlorpyrifos-only induced numerous histopathological changes in the testis tissues. Milder pathological alterations were observed in rats catechin-plus-chlorpyrifos, and quercetin-plus-chlorpyrifos. Thus, it appears that catechin and quercetin ameliorate chlorpyrifos induced toxicity except histopathological changes in rat testis tissues.
Environmental Toxicology | 2009
Dilek Durak; Fatma Gokce Uzun; Suna Kalender; Ayse Ogutcu; Meltem Uzunhisarcikli; Yusuf Kalender
Malathion is an organophosphate (OP) pesticide that has been shown to induce oxidative stress in erythrocytes through the generation of free radicals and alteration of the cellular antioxidant defense system. We examined the effect of several different doses of malathion (25, 75, 200 μM), or malathion in combination with vitamin C (VC; 10 μM) or vitamin E (VE; 30 μM), on the levels of malondialdehyde (MDA), and superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx) activities in human erythrocytes in vitro. Erythrocytes were incubated under various treatment conditions (malathion alone, vitamins alone, or malathion plus vitamin) at 37°C for 60 min, and the levels of MDA, and SOD, CAT and GPx activities, were determined. Treatment with malathion alone increased the levels of MDA and decreased SOD, CAT, and GPx activities in erythrocytes (P < 0.05). There were no statistical differences among VC‐treated, VE‐treated, or VC + VE‐treated erythrocyes, as compared with nontreated control cells. Treatment of cells with malathion + VC, malathion + VE, or a combination of all three agents prevented malathion‐induced changes in antioxidant enzyme activity and lipid peroxidation. However, this effect was seen only at low concentrations of malathion (25 and 75 μM), and the combination of VC + VE had a more protective effect than VC or VE alone. These results indicated that the presence of vitamins at concentrations that are similar to the levels found in plasma have no effect on malathion‐induced toxicity in erythrocytes at a concentration of malathion (200 μM) that is typically used in pesticides.
Food and Chemical Toxicology | 2013
Fatma Gokce Uzun; Yusuf Kalender
Chlorpyrifos is an organophosphorus insecticide which is widely used throughout in the world and it caused toxic effects on nontarget organisms especially mammalian. In the present study, catechin, quercetin, chlorpyrifos, catechin+chlorpyrifos, quercetin+chlorpyrifos were given to male rats through gavage for 4weeks. Serum total protein, albumin, aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase, lactate dehydrogenase, trigliceride, total cholesterol levels, hematological changes, superoxide dismutase, catalase, glutathione peroxidase, glutathione-S-transferase activities and malondialdehyde content in liver tissues and also histopathological changes of liver were investigated in the rats compared to control group. No significant differences in all investigated parameters were observed between control, catechin and quercetin groups. There were statistically significantly changes in liver function tests, some hematological parameters, antioxidant enzyme activities and malondialdehyde levels in chlorpyrifos treated group compared to control group. In catechin+chlorpyrifos treated group and quercetin+chlorpyrifos treated group we observed the protective effects of catechin and quercetin on examining parameters but not completely. While some histopathological changes detected in liver tissues in chlorpyrifos treated group, less histopathological changes were observed in catechin+chlorpyrifos and quercetin+chlorpyrifos treated groups at the end of the 4thweek. As a result, catechin and quercetin significantly reduce chlorpyrifos induced hepatotoxicity in rats.
Food and Chemical Toxicology | 2010
Fatma Gokce Uzun; Filiz Demir; Suna Kalender; Hatice Baş; Yusuf Kalender
The mature male Wistar rats (n=36, 300-320 g) were divided into six groups having six animals, i.e., Group I (control), Group II (catechin, 20 mg/kg bw), Group III (quercetin, 20 mg/kg bw), Group IV (chlorpyrifos 5.4 mg/kg, 1/25 LD50), Group V (catechin+chlorpyrifos) and Group VI (quercetin+chlorpyrifos). Rats were given chlorpyrifos, catechin and quercetin daily via gavage for 4 weeks. Chlorpyrifos increased the levels of malondialdehyde (MDA), superoxide dismutase (SOD), and catalase (CAT), and decreased glutathione peroxidase (GPx) and glutathione-S-transferase (GST) activities in lung tissues compared to the control group. In the catechin plus chlorpyrifos- and quercetin plus chlorpyrifos-treated groups, there were statistically significant increases in CAT and SOD activities, while no statistically significant changes were observed in MDA, GST and GPx activities relative to the control. Compared to the chlorpyrifos-treated group, however, the catechin plus chlorpyrifos- and quercetin plus chlorpyrifos-treated groups showed significantly increased GST and GPx activity, while the activity of MDA, SOD and CAT was significantly decreased. Light microscopic investigations revealed that 4 weeks of chlorpyrifos exposure induced numerous histopathological alterations in the lung. Milder histopathological changes were observed in animals co-treated with catechin plus chlorpyrifos or quercetin plus chlorpyrifos. Thus, it appears that catechin and quercetin ameliorate chlorpyrifos-induced lung toxicity but are not completely protective.
Brazilian Journal of Medical and Biological Research | 2002
Suna Kalender; Yusuf Kalender; A. Ates; Mustafa Yel; E. Olcay; Selami Candan
Idarubicin is an anthracycline antibiotic extensively used in acute leukemia. In the present study we investigated whether vitamin E and catechin can reduce the toxic effects of idarubicin. Vitamin E (200 IU kg(-1) week(-1)), catechin (200 mg kg(-1) week(-1)), idarubicin (5 mg kg(-1) week(-1)), idarubicin + vitamin E (200 IU kg(-1) week(-1)), and idarubicin + catechin (200 mg kg(-1) week(-1)) combinations were given to male Sprague-Dawley rats weighing 210 to 230 g (N = 6/group). Idarubicin-treated animals exhibited a decrease in body and heart weight, a decrease in myocardial contractility, and changes in ECG parameters (P<0.01). Catechin + idarubicin- and vitamin E + idarubicin-treated groups exhibited similar alterations, but changes were attenuated in comparison to those in cardiac muscle of idarubicin-treated rats (P<0.05). Superoxide dismutase and catalase activity was reduced in the idarubicin-treated group (P<0.05). Glutathione peroxidase levels were decreased in the idarubicin-treated group (P<0.05) and reached maximum concentrations in the catechin- and catechin + idarubicin-treated groups compared to control (P<0.01). Malondialdehyde activity was decreased in the catechin + idarubicin-treated groups compared to control and increased in the other groups, reaching maximum concentrations in the vitamin E-treated group (P<0.01). In electron microscopy studies, swelling of the mitochondria and dilatation of the sarcoplasmic reticulum of myocytes were observed in the idarubicin-treated groups. In groups that were given idarubicin + vitamin E and idarubicin + catechin, the only morphological change was a weak dilatation of the sarcoplasmic reticulum. We conclude that catechin and vitamin E significantly reduce idarubicin-induced cardiotoxicity in rats.
Folia Biologica | 2005
Ayoe Ogutcu; Zekiye Suludere; Meltem Uzunhisarcikli; Yusuf Kalender
In this study effects of Bacillus thuringiensis kurstaki (Btk) on Malpighian tubule cells of Thaumetopoea pityocampa (Lepidoptera: Thaumetopoeidae) larvae was investigated by electron microscopy. 3 mg/l Btk was given with food. After Btk administration, the Malpighian tubule cells were investigated and compared with a control group. 3 and 6 hrs after Btk administration swelling in Malpighian tubule cells was observed. Swelling of mitochondria and separation of their cristae was seen after 12 hrs. After 24 hrs dissolution of the basal cytoplasm, swelling and vacuolization of all mitochondria, partial dissolution of the nucleoplasm, and swelling and separation ofmicrovilli was documented. A membrane-body in the nucleus was seen after 48 hrs. The nucleoplasm was completely dissolved after 72 hrs and after 96 hrs large vacuoles appeared in the cytoplasm and shortening of microvilli was observed.Compared to current treatments including surgery, radiation therapy, and chemotherapy, PDT offers the advantage of an effective and selective method of destroying diseased tissues without damaging surrounding healthy tissues. One of the aspects of antitumour effectiveness of PDT is related to the distribution of photosensitizing drugs. The localization of photosensitizers in cytoplasmic organelles during PDT plays a major role in the cell destruction; therefore, intracellular localization of Ph in malignant and normal cells was investigated. The cell lines used throughout the study were: human malignant A549, MCF-7, Me45 and normal endothelial cell line HUV-EC-C. After incubation with Ph cells were examined using fluorescence and confocal microscopy to visualize the photosensitizer accumulation. For cytoplasm and mitochondria identification, cells were stained with CellTracker Green and MitoTracker Green, respectively. Distribution of Ph was different in malignant and normal cells and dependent on the incubation time. The maximal concentration of Ph in two malignant cell lines (A549 and MCF-7) was observed after 4 hours of incubation, and the most intensive signal was observed around the nuclear envelope. Intracellular distribution of Ph in the Me45 cell line showed that the fluorescence emitted by Ph overlaid that from MitoTracker. This indicates preferential accumulation of the sensitizer in mitochondria. Our results based on the mitochondrial localization support the idea that PDT can contribute to elimination of malignant cells by inducing apoptosis, which is of physiological significance.