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Öğe Attenuation of ischemia/reperfusion-induced ovarian damage in rats: Does edaravone offer protection?(S. Karger AG, 2013) Ergenoglu M.; Erbaş O.; Akdemir A.; Yeniel A.O.; Yildirim N.; Oltulu F.; Aktug H.; Taskiran D.Aim: The aim of this study was to investigate whether prophylactic treatment with edaravone prevents ischemia/reperfusion (I/R)-induced ovarian damage during pneumoperitoneum in an experimental rat model. Methods: Twenty-eight female Sprague Dawley rats were allocated randomly to 4 groups. The sham group (group 1) was only subjected to catheter insertion, not to pneumoperitoneum. Group 2 received a 1 mg/kg dose of 0.9% sodium chloride by the intraperitoneal route for 10 min before pneumoperitoneum. Groups 3 and 4 received 6 and 12 mg/kg edaravone, respectively, by the intraperitoneal route for 10 min before pneumoperitoneum. After 60 min of pneumoperitoneum, the gas was deflated. Immediately after the reperfusion period, both ovaries were excised for histological scoring, caspase-3 immunohistochemistry and biochemical evaluation including glutathione (GSH) and malondialdehyde (MDA) levels. Also, total antioxidant capacity (TAC) was measured in plasma samples to evaluate the antioxidant effect of edaravone. Results: Ovarian sections in the saline group revealed higher scores for follicular degeneration and edema (p < 0.0001) when compared with the sham group. Administration of different doses of edaravone in rats significantly prevented degenerative changes in the ovary (p < 0.0001). Caspase-3 expression was only detected in the ovarian surface epithelium in all groups, and there was a significant difference between the treatment groups and the saline group (p < 0.0001). Treatment of rats with edaravone reduced caspase-3 expression in a dose-dependent manner. Moreover, biochemical measurements of oxidative stress markers (MDA, GSH and TAC) revealed that prophylactic edaravone treatment attenuated oxidative stress induced by I/R injury. Conclusion: These results indicate that prophylactic treatment with edaravone prevents I/R-induced ovarian damage during pneumoperitoneum in an experimental rat model. © 2013 S. Karger AG, Basel.Öğe Comparison of montelukast and cabergoline for prevention of ovarian hyperstimulation syndrome: In an experimental rat model(Informa Healthcare, 2015) Akman L.; Sahin G.; Erbas O.; Aktug H.; Akdogan A.; Goker E.N.T.; Taskiran D.; Tavmergen E.Ovarian hyperstimulation syndrome (OHSS) is a serious iatrogenic complication that can occur during assisted reproductive techniques. The aim of this study is to investigate the effects of the leukotriene receptor antagonist (montelukast) treatment in prevention of OHSS and compare to cabergoline treatment. Twenty-four immature female Wistar rats were assigned to four groups. Group 1 was the control group. In the remaning three groups, OHSS was induced through ovarian stimulation with gonadotropins. No treatment was given to Group 2. Group 3 was administered a low-dose 100 mg/kg cabergoline treatment and Group 4 was received 20 mg/kg montelukast. Body weight, ovarian weight, vasculary permability (VP), peritoneal fluid vascular endothelial growth factor (VEGF) values and VEGF immune-expression were compared between the groups. Both cabergoline and montelukast prevented progression of OHSS compared to the OHSS group. Body weight, ovarian weight, VP, peritoneal fluid VEGF values and VEGF expression were significantly lower in both cabergoline- and montelukast-treated rats than in those not treated OHSS group. In conclusion, montelukast is an effective option for prevention of OHSS, as well as cabergoline. Montelukast may be a new treatment option to prevent and control the OHSS. © 2015 Informa UK Ltd. All rights reserved: reproduction in whole or part not permitted.Öğe Cytotoxicity in astrocyte cultures due to pH changes and protection by glutathione [Astrosit hücre kültürlerinde pH degiş ikliginin yarattigi toksisite ve glutatyonun koruyucu etkisi](2010) Yilmaz O.; Taskiran D.Background: It is well known that extracellular and intracellular pH changes have cytotoxic effects on astrocytes and neurons. In the present study, we aimed to evaluate the cytotoxic effects of acidosis on astrocyte cultures by measuring cell death and oxidative stress parameters. We also investigated the protective effects of ascorbic acid and gluthatione as antioxidants against toxicity due to pH changes in the cultures. Materials and Methods: Primary astrocyte cultures were prepared from 1-2 day old neonatal rats. Astrocytes were incubated in media with or without pH 5,5 ± 0,1 for 2 h and treated with ascorbic acid (AA, 1 mM) and glutathione (GSH, 1 mM). The effects of acidosis and antioxidants were assessed by measuring lactate dehydrogenase (LDH), superoxide dismutase (SOD) and catalase activities and nitrite levels in the cultures. Results: LDH activity, nitrite levels and antioxidant enzyme activities were found significantly elevated in the acidosis group than the control (p< 0.0005). Treatment of the astrocytes with GSH decreased cell death, nitrite levels and antioxidant enzyme activities compare to the acidosis group. Although the treatment of the cultures with AA lowered antioxidant enzyme activities and ntirite levels, there was no protective effect on astrocyte viability. Conclusions: Our results demonstrated that decreased of pH levels may effect astrocyte viability and antioxidant enzyme activities. Treatment of the astrocytes with GSH may protect them from cytotoxicity and oxidative stress. Overall, these results support that acidosis and oxidative stress closely interact with each other and may trigger cell damage in brain.Öğe Effect of oxytocin treatment on explant size, plasma and peritoneal levels of MCP-1, VEGF, TNF-? and histopathological parameters in a rat endometriosis model(Elsevier Ireland Ltd, 2014) Yeniel A.Ö.; Erbas O.; Ergenoglu A.M.; Aktug H.; Taskiran D.; Yildirim N.; Ulukus M.Objective: To determine the effects of oxytocin (OT) on surgically induced endometriosis in a rat model. Study design: Twelve female Sprague-Dawley rats were included. After the implantation and establishment of autologous endometrium onto the abdominal wall peritoneum, the rats were randomly divided into two groups, treated with intramuscular oxytocin (OT group, 160 µg kg/day, n = 6) or isotonic NaCl solution (control group, 1 mL kg/day, n = 6) for 28 days. To evaluate the therapeutic effects of OT, the explant volumes were calculated and the levels of vascular endothelial growth factor (VEGF), monocyte chemotactic protein-1, and TNF-? were measured in plasma and peritoneal fluid. Endometriotic explants were examined histologically by semiquantitative analysis. Results: After treatment, the mean endometriotic explant volume was decreased in the OT group (p = 0.016). The histopathological score and VEGF immunoexpression of endometriotic explants were significantly lower in the OT group (p = 0.007) than in controls (p = 0.000). Inflammatory cytokine levels in plasma and peritoneal fluid were considerably decreased in the OT group. Moreover, TUNEL immunohistochemistry clearly demonstrated more apoptotic changes in the mononuclear cells of the OT group compared with controls. Conclusion: We suggest that oxytocin might be considered as a potential candidate therapeutic agent for endometriosis. © 2014 Elsevier Ireland Ltd. All rights reserved.Öğe Effects of resveratrol on ovarian morphology, plasma anti-mullerian hormone, IGF-1 levels, and oxidative stress parameters in a rat model of polycystic ovary syndrome(SAGE Publications Inc., 2015) Ergenoglu M.; Yildirim N.; Yildirim A.G.S.; Yeniel O.; Erbas O.; Yavasoglu A.; Taskiran D.; Karadadas N.Objective: To evaluate the effects of resveratrol in a rat model of polycystic ovarian syndrome (PCOS). Study Design: After PCOS model was formed by subcutaneous dihydrotestosterone pellets, rats were randomly divided into 2 groups. The first group (n = 7) was treated with 1 mL/kg/d isotonic saline and the second group (n = 7) was treated with 10 mg/kg/d resveratrol. Seven rats were taken as controls without any medication. Results: Our results showed (1) significant reduction in the number of antral follicle counts (P < .01); (2) significantly decreased plasma anti-Mullerian hormone and insulin-like growth factor 1 levels (P < .01 and P < .05, respectively); (3) significantly lower superoxide dismutase activity (P < .05); and (4) significantly increased glutathione peroxidase content (P < .01) following resveratrol treatment. Conclusion: Resveratrol appears to be effective in the treatment of PCOS due to its antioxidant properties. Future clinical studies with different dosages might provide useful implementations to our practice. © The Author(s) 2015.Öğe Estradiol protects adipose tissue-derived stem cells against H2O2-induced toxicity(2012) Taskiran D.; Evren V.Oxidative stress is associated with various pathophysiological processes, including cell survival, adhesion, apoptosis, and cancer. In the present study, we aimed to evaluate the effects of H2O2-induced toxicity on adipose tissue-derived stem cells (ADSCs) and whether 17ß-estradiol (E2) has protective effects on these cells. ADSCs derived from adult Sprague-Dawley rats were pretreated with different doses of E2 for 24 h and then exposed to 200 µM H2O2 for 4 h. Incubation of ADSCs with H2O2-decreased cell viability in a concentration-dependent fashion (p < 0.0001), whereas pretreatment of these cells with E2 significantly reversed toxicity (p < 0.05), inhibited apoptotic changes, and decreased lipid peroxidation (p < 0.0005). Our findings suggest that E2 protects ADSCs from oxidative-induced cell death, and therefore, it may be used to improve the survival rate and regenerative capacity of stem cells. © 2012 Wiley Periodicals, Inc.Öğe The investigation of the antitumor agent toxicity and capsaicin effect on the electron transport chain enzymes, catalase activities and lipid peroxidation levels in lung, heart and brain tissues of rats(MDPI AG, 2018) Kursunluoglu G.; Taskiran D.; Kayali H.A.Cisplatin is one of the most active cytotoxic agents in cancer treatment. To clarify the interaction with mitochondria, we hypothesize that the activities of mitochondrial electron transport chain (ETC) enzymes succinate dehydrogenase (SDH) and cytochrome c oxidase (COX), nucleotide levels, as well as levels of catalase (CAT) enzyme and membrane lipid peroxidation (LPO) can be affected by cisplatin. There was a significant decrease of both SDH and COX activities in the lung, heart, and brain tissues at the 1st day after cisplatin exposure, and the observed decreased levels of adenosine triphosphate (ATP) and adenosine diphosphate (ADP) in comparison with the control could be because of cisplatin-induced mitochondrial dysfunction. The investigations suggested that cisplatin inhibits SDH, COX, and ATP synthase. The higher LPO level in the studied tissues after 1 and 4 days post-exposure to cisplatin compared to control can be inferred to be a result of elevated electron leakage from the ETC, and reactive oxygen species (ROS) can lead to wide-ranging tissue damage such as membrane lipid damage. Consequently, it was observed that capsaicin may have a possible protective effect on ETC impairment caused by cisplatin. The activities of SDH and COX were higher in heart and brain exposed to cisplatin + capsaicin compared to cisplatin groups, while LPO levels were lower. The investigated results in the cisplatin + capsaicin groups suggested that the antioxidant capacity of capsaicin scavenges ROS and prevents membrane destruction. © 2018 by the authors.Öğe Oxytocin improves follicular reserve in a cisplatin-induced gonadotoxicity model in rats(Hindawi Publishing Corporation, 2014) Erbaş O.; Akman L.; Yavaşoglu A.; Terek M.C.; Akman T.; Taskiran D.Cisplatin (CP), an antitumor agent, has been shown to cause ovarian injury and dysfunction in both animal and human studies. The present study was conducted to investigate the protective effect of oxytocin (OT) on CP-induced ovarian toxicity in rats. Twenty-one adult female rats were included in the study. Fourteen rats were administered intraperitoneally CP (2 mg/kg/day) twice a week for 5 weeks. Control group (n = 7) did not receive any treatment. Following treatment, CP-received rats were randomly divided into two groups and treated with either saline (1 mL/kg/day, n = 7) or OT (160 g/kg/day, n = 7) for 5 weeks. Then, ovarian toxicity and effects of OT were evaluated by histomorphological and biochemical analysis. Our findings revealed a significant reduction in the number of follicles at each grade in saline-treated group. AMH level was significantly lower in saline group compared to control (P < 0.0005). OT treatment significantly attenuated CP toxicity in ovaries and increased AMH levels compared to saline group (P < 0.005). Also, administration of OT lessened lipid peroxidation and prevented glutathione depletion in CP-treated rats (P < 0.05). These results indicated that OT could lessen the CP-induced ovarian damage and improve follicular reserve by preventing oxidative damage. © 2014 Oytun Erbaş et al.Öğe The preventive effect of oxytocin to cisplatin-induced neurotoxicity: An experimental rat model(Hindawi Limited, 2015) Akman T.; Akman L.; Erbas O.; Terek M.C.; Taskiran D.; Ozsaran A.Peripheral neurotoxicity is a frequent dose-limiting side effect of the chemotherapeutic agent cisplatin. This study was conducted to investigate the preventive effect of oxytocin (OT) on cisplatin-induced neurotoxicity in rats. Forty-four adult female rats were included in the study. Thirty-six rats were administered intraperitoneally (i.p.) single dose cisplatin 10 mg/kg and divided in to 3 groups. The first group (n=12) received saline i.p., whereas the second group (n=12) and the third group (n=12) were injected with 80 µg/kg and 160 µg/kg OT, respectively, for 10 days. The remaining 8 rats served as the control group. Electromyography (EMG) studies were recorded and blood samples were collected for the measurement of plasma lipid peroxidation (malondialdehyde; MDA), tumor necrosis factor (TNF)-?, and glutathione (GSH) levels. EMG findings revealed that compound muscle action potential amplitude was significantly decreased and distal latency was prolonged in the nontreated cisplatin-injected rats compared with the control group (P<0.005). Also, nontreated cisplatin-injected rats showed significantly higher TNF-? and MDA levels and lower GSH level than control group. The administration of OT significantly ameliorated the EMG alterations, suppressed oxidative stress and inflammatory parameters, and increased antioxidative capacity. We suggest that oxytocin may have beneficial effects against cisplatin-induced neurotoxicity. © 2015 Tulay Akman et al.Öğe Protective effect of edaravone against manganese-induced toxicity in cultured rat astrocytes(Elsevier, 2015) Evren V.; Apaydin M.; Khalilnezhad A.; Erbas O.; Taskiran D.Manganese (Mn), a trace metal, is essential for maintaining the normal regulation of many biochemical and cellular processes. However, accumulation of Mn due to excessive environmental exposure leads to neurological impairment, referred to as manganism. Edaravone (EDA) is a potent free radical scavenger that has been clinically shown to reduce the neuronal injury after cerebral ischemia. In the present study, we aimed to examine the protective effects of EDA against Mn toxicity in astrocyte cultures. Astrocyte cultures were prepared from cerebral cortices of newborn Sprague-Dawley rats. The experiments were performed between 16 and 18 days of cultures. Astrocytes were treated in DMEM medium containing Mn (1-1000. µM) for 24. h to test Mn toxicity. In order to assess the effect of EDA, cells were pre-treated with different doses of EDA (10, 100 and 1000. µM) 6. h before Mn treatment. Cell viability (MTT), apoptotic cell death (Hoechst test) and lipid peroxide levels were evaluated in cultures. Our results showed that Mn significantly and dose-dependently reduced cell viability in astrocyte cultures. The apoptotic cell death and lipid peroxides were significantly higher in Mn treated cultures. Treatment of astrocytes with EDA successfully suppressed oxidative stress and cell death due to Mn exposure. The findings of the present study suggest that Mn cytotoxicity is mainly associated with ROS generation and apoptotic cell death. Besides, EDA may have beneficial effects against Mn toxicity. However, further studies are needed to elucidate the molecular mechanisms underlying protective effect of EDA. © 2015 Elsevier B.V.Öğe Regression of endometrial implants by resveratrol in an experimentally induced endometriosis model in rats(2013) Ergenoglu A.M.; Yeniel A.O.; Erbaş O.; Aktug H.; Yildirim N.; Ulukuş M.; Taskiran D.Objective: To evaluate the effect of resveratrol on an experimentally induced endometriosis rat model. Study design: After endometriotic implants were surgically formed, rats were randomly divided into 2 groups as control group (saline treated, n = 6) and resveratrol group (10 mg/kg/d, n = 6). The inflammatory markers and histopathological changes were assessed at the end of the treatment period. Results Our results showed (1) significant reduction in the implant size (P < .0005); (2) significantly decreased levels of vascular endothelial growth factor (VEGF) in the peritoneal fluid and plasma (P < .005); and monocyte chemotactic protein 1 (MCP-1) in the peritoneal fluid (P < .05), (3) highly significant suppression of VEGF expression in the endometriotic tissue (P < .0005); and (4) considerable histological changes in the endometriotic foci following resveratrol treatment. Conclusion: Resveratrol appears to be effective on the development of endometriosis through its antiangiogenic and anti-inflammatory properties. Future studies with different doses of resveratrol might provide more comprehensive results regarding the treatment of endometriosis. © The Author(s) 2013.Öğe The role of nitric oxide in proteoglycan turnover by bovine articular cartilage organ cultures(1996) Stefanovic-Racic M.; Morales T.I.; Taskiran D.; McIntyre L.A.; Evans C.H.Monolayer cultures of articular chondrocytes synthesize large amounts of nitric oxide (NO) following exposure to IL-1. The latter has antianabolic and procatabolic activities on these cells, but little is known about the role, if any, of NO in the integrated metabolic pathways of the chondrocyte. In the present study, the role of endogenously produced NO in both the synthesis and degradation of proteoglycans was investigated for the first time. Bovine articular cartilage slices exposed to 20 U/ml human rIL-1ß (hrIL-1ß) synthesized large amounts of NO for 1 to 2 days, after which production fell to a steady state level ~20% of the peak value for the remainder of the 14- day incubation. The NO synthase inhibitor, N-monomethyl L-arginine (L-NMA, 1 mM), blocked NO production and enhanced the acute catabolic effects of hrIL- 1ß in cartilage derived from both calves and adult animals. However, in late cultures, release of proteoglycans was reduced in the presence of L-NMA. The proteolytic activity in conditioned medium of these cultures (measured as caseinolytic activity) was enhanced by L-NMA; however, this inhibitor did not affect the rates of synthesis of proteoglycans. Although NO is widely assumed to be a mediator of cartilage catabolism, our data suggest that it may instead have an acute protective effect. Whether this effect is maintained chronically is less clear.Öğe Stimulatory effect of 17ß-estradiol on osteogenic differentiation potential of rat adipose tissue-derived stem cells(2011) Taskiran D.; Evren V.Adipose tissue-derived stem cells (ADSCs) are considered as a potential cell source for regenerative medicine and tissue engineering. Although ADSCs have greater proliferation capacity than bone marrow stem cells (BMSCs), lower differentiation ability of these cells limits their utility in experimental and clinical studies. The purpose of this study was to investigate whether 17ß-estradiol (E2) has a stimulatory effect on osteogenic differentiation potential of ADSCs in vitro. ADSCs were isolated from visceral adipose tissues of rats and treated with different concentrations of E 2 in osteogenic medium (OM) for 21 days. The differences in osteogenic differentiation potential of the cultures were assessed by von Kossa staining, measurement of alkaline phosphatase (ALP) activity and calcium levels. ADSCs cultured in OM supplemented with E2 showed greater bone-like nodule formation and mineral deposition in comparing with the cells grown in OM. In addition, ALP activity and calcium levels also were significantly higher in the cultures exposed to E2 than the cells treated only with OM (p < 0.005, n = 5). Our results suggest that E2 may stimulate the osteogenic differentiation of ADSCs and therefore, can be used as an inducing agent to improve the efficiency of these cells in in vitro and in vivo studies.
