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VELİOĞLU ÖĞÜNÇ, AYLİZ

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VELİOĞLU ÖĞÜNÇ

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AYLİZ

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  • Publication
    Acetaminophen-induced toxicity is prevented by beta-D-glucan treatment in mice
    (ELSEVIER SCIENCE BV, 2006) VELİOĞLU ÖĞÜNÇ, AYLİZ; Toklu, Hale Z.; Sehirli, A. Ozer; Velioglu-Ogunc, Ayliz; Cetinel, Sule; Sener, Goksel
    The protective effect of beta-glucan against oxidative injury caused by acetaminophen was studied in mice liver. BALB-c mice (25-30 g) were pretreated with beta-D-glucan (50 mg/kg, p.o.) for 10 days and on the 11th day they received an overdose of acetaminophen (900 mg/kg, i.p.). Four hours after the acetaminophen injection, mice were decapitated and their blood was taken to determine serum aspartate aminotransferase (AST), alanine aminotransferase (ALT), lactate dehydrogenase (LDH) and tumor necrosis factor-alpha (TNF-alpha) levels. Tissue samples of the liver were taken for histological examination or for the determination of levels of malondialdehyde, an end product of lipid peroxidation; glutathione (GSH), a key antioxidant; and myeloperoxidase activity, an index of tissue neutrophil infiltration. The formation of reactive oxygen species in hepatic tissue samples was monitored by using the chemilummescence technique with luminol and lucigenin probes. Acetaminophen caused a significant decrease in the GSH level of the tissue, which was accompanied with significant increases in the hepatic luminol and lucigenin chemiluminescence values, malondialdehyde level, MPO activity and collagen content. Similarly, serum ALT, AST levels, as well as LDH and TNF-alpha, were elevated in the acetaminophen-treated group when compared with the control group. On the other hand, P-D-glucan treatment reversed all these biochemical indices, as well as histopathological alterations that were induced by acetaminophen. In conclusion, these results suggest that beta-D-glucan exerts cytoprotective effects against oxidative injury through its antioxidant properties and may be of therapeutic use in preventing acetaminophen toxicity. (c) 2006 Elsevier B.V. All rights reserved.
  • Publication
    Protective effects of resveratrol against acetaminophen-induced toxicity in mice
    (WILEY, 2006) VELİOĞLU ÖĞÜNÇ, AYLİZ; Sener, Goksel; Toklu, Hale Z.; Sehirli, A. Ozer; Velioglu-Ogunc, Ayliz; Cetinel, Sule; Gedik, Nursal
    This investigation elucidates the role of free radicals in acetaminophen (AA)-induced toxicity and the possible protection by resveratrol (RVT). BALB-c mice were injected with a single dose of 900 mg/kg AA to induce toxicity, while RVT administred in a dose of 30 mg/kg i.p. following AA. Mice were sacrificed 4 h after AA injection to determine serum ALT, AST and tumor necrosis factor-alpha (TNF-alpha) levels in blood, and glutathione (GSH), malondialdehyde (MDA) levels, myeloperoxidase (MPO) activity and collagen contents in liver tissues. Formation of reactive oxygen species in hepatic tissue samples was monitored by using chemiluminescence (CL) technique with luminol and lucigenin probe. ALT, AST levels and TNF-alpha were increased significantly after AA treatment, and reduced with RVT. AA caused a significant decrease in GSH levels while MDA levels and MPO activity were increased in liver tissues. On the other hand when RVT administered following AA, depletion of GSH and accumulation of MDA and neutrophil infiltration were reversed back to control. Furthermore increased luminol and lucigenin CL levels in the AA group reduced by RVT treatment. Our results implicate that AA causes oxidative damage in hepatic tissues and RVT, by its potent antioxidant effects protects the liver tissue. These data suggest that RVT may be of therapeutic use in preventing hepatic oxidative injury due to AA toxicity. (c) 2006 Elsevier Ireland Ltd. All rights reserved.
  • Publication
    The effects of spironolactone in preventing bile duct ligation-induced hepatitis in a rat model
    (Iranian Journal of Pharmaceutical Research, 2021) VELİOĞLU ÖĞÜNÇ, AYLİZ; Özer Şehirli A., Kökeş A., Velioğlu-öğünç A., Tetik Ş., Özkan N., Çetinel Ş., Sayıner S., Dülger G.
    Cholestasis is associated with the accumulation of bile acids and bilirubin in the hepatocytes and leads to liver injury. Pregnane X Receptor (PXR) coordinates protective hepatic responses to toxic stimuli, and this receptor was reported to stimulate bile secretion by increasing MRP2 expression. Since PXR activators were reported to be anti-inflammatory in the liver, PXR was proposed as a drug target for the treatment of chronic inflammatory liver diseases. We investigated the potential protective effect of spironolactone (SPL), an enzyme inducer, in hepatotoxicity induced by bile duct ligation in rats. Wistar Albino (250-300 g) rats were divided into the control group and the bile duct ligated (BDL) group. BDL group was divided into three subgroups; following BDL, for 3 days, the first group received propylene glycol (vehicle of SPL) (blinded), the second subgroup received spironolactone (SPL) (200 mg/kg oral), and the third subgroup received SPL for 3 days, starting 3 days after the bile duct ligation, in order to investigate if it has a healing effect after hepatitis had developed. The control group was sham-operated and received saline. At the end of the experiment, blood and tissue samples were collected. Serum TNF-α, NF-ĸB, bilirubin, IL-6 levels, ALT, AST, ALP activities and tissue MPO activity and oxidant damage increased after the bile duct ligation was significantly decreased following SPL administration. PXR and MRP2 activity showed an increase in the hepatocytes as a result of the treatment. In conclusion, it was observed that SPL administration significantly decreases liver inflammation and damage related to BDL. © 2021, Iranian Journal of Pharmaceutical Research. All rights reserved.
  • Publication
    Oxytocin alleviates oxidative renal injury in pyelonephritic rats via a neutrophil-dependent mechanism
    (ELSEVIER SCIENCE INC, 2006) VELİOĞLU ÖĞÜNÇ, AYLİZ; Biyikli, Nese Karaaslan; Tugtepe, Halil; Sener, Goksel; Velioglu-Ogunc, Ayliz; Cetinel, Sule; Midillioglu, Sukru; Gedik, Nursal; Yegen, Berrak C.
    Background: Urinary tract infection (UTI) may cause inflammation of the renal parenchyma and may lead to impairment in renal function and scar formation. Oxidant injury and reactive oxygen species (ROS) have been found responsible in the pathogenesis of UTI. The neurohypophyseal hormone oxytocin (OT) facilitates wound healing and is involved in the modulation of immune and inflammatory processes. We investigated the possible therapeutic effects of OT against Eschericia coli induced pyelonephritis in rats both in the acute and chronic setting. Methods: Twenty-four Wistar rats were injected 0.1 ml solution containing E. coli ATCC 25922 10(10) colony forming units/ml into left renal medullae. Six rats were designed as sham group and were given 0.1 ml 0.9% NaCl. Pyelonephritic rats were treated with either saline or OT immediately after surgery and at daily intervals. Half of the pyelonephritic rats were decapitated at the 24th hour of E. coli infection, and the rest were followed for 7 days. Renal function tests (urea, creatinine), systemic inflammation markers [lactate dehydrogenase (LDH) and tumor necrosis factor alpha (TNF-alpha)] and renal tissue malondialdehyde (MDA) as an end product of lipid peroxidation, glutathione (GSH) as an antioxidant parameter and myeloperoxidase (MPO) as an indirect index of neutrophil infiltration were studied. Results: Blood urea, creatinine, and TNF-a levels were increased, renal tissue MDA and MPO levels were elevated and GSH levels were decreased in both of the pyelonephritic (acute and chronic) rats. All of these parameters and elevation of LDH at the late phase were all reversed to normal levels by OT treatment. Conclusion: OT alleviates oxidant renal injury in pyelonephritic rats by its anti-oxidant actions and by preventing free radical damaging cascades that involves excessive infiltration of neutrophils. (c) 2006 Elsevier Inc. All rights reserved.
  • Publication
    Resveratrol protects against irradiation-induced hepatic and ileal damage via its anti-oxidative activity
    (TAYLOR & FRANCIS LTD, 2009) VELİOĞLU ÖĞÜNÇ, AYLİZ; Velioglu-Ogunc, Ayliz; Sehirli, Ozer; Toklu, Hale Z.; Ozyurt, Hazan; Mayadagli, Alpaslan; Eksioglu-Demiralp, Emel; Erzik, Can; Cetinel, Sule; Yegen, Berrak C.; Sener, Goeksel
    The present study was undertaken to determine whether resveratrol (RVT) could ameliorate ionizing radiation-induced oxidative injury. After a 10-days pre-treatment with RVT (10 mg/kg/day p.o.), rats were exposed to whole-body IR (800 cGy) and the RVT treatment was continued for 10 more days after the irradiation. Irradiation caused a significant decrease in glutathione level, while malondialdehyde levels, myeloperoxidase activity and collagen content were increased in the liver and ileum tissues. Similarly, plasma lactate dehydrogenase and pro-inflammatory cytokine levels, 8-hydroxy-2'-deoxyguanosine and leukocyte apoptosis were elevated, while antioxidant-capacity was reduced in the irradiated rats as compared with the control group. Furthermore, Na-1, K-1 -ATPase activity was inhibited and DNA fragmentation was increased in the ileal tissues. Resveratrol treatment reversed all these biochemical indices, as well as histopathological alterations induced by irradiation. In conclusion, supplementing cancer patients with adjuvant therapy of resveratrol may have some benefit for a more successful radiotherapy.
  • PublicationOpen Access
    Protective effects of St. John's wort in the hepatic ischemia/reperfusion injury in rats
    (AVES, 2018-09-28) VELİOĞLU ÖĞÜNÇ, AYLİZ; Atalay, Suleyman; Soylu, Belkis; Aykac, Asli; Ogunc, Ayliz Velioglu; Cetinel, Sule; Ozkan, Naziye; Erzik, Can; Sehirli, Ahmet Ozer
    Objectives: The purpose of this study was to investigate possible protective effects of St. John's wort in the hepatic ischemia/reperfusion injury. Material and Methods: The hepatic artery, portal vein, and bile duct were all clamped for 45 minutes to induce ischemia in rats, and after that reperfusion for 1 hour. SJW was administrated orally, once a day for 3 days before ischemia/reperfusion. The aspartate aminotransferase, alanine aminotransferase, tumor necrosis factor, and interleukin levels were measured in the serum samples. Luminol chemiluminescence, lucigenin luminol chemiluminescence levels; myeloperoxidase. The sodium-potassium ATPase (Na+/K+ ATPase) activity was determined in the liver tissue, and caspase-3 and caspase-9 activity with the bcl-2/bax ratio were measured by the western blot analysis. Results: The St. John's wort administration recovered the aspartate aminotransferase, alanine aminotransferase, tumor necrosis factor, and IL-1 beta levels serum parameters meaningfully, while ischemia/reperfusion caused an increase in luminol chemiluminescence, lucigenin luminol chemiluminescence, myeloperoxidase, caspase-3, and caspase-9 activity and led to a decrease in the B-cell lymphoma-2/bcl-2-associated X protein (bcl-2/bax) ratio and the Na+/K+ ATPase activity. Conclusion: The obtained results indicate protective effects of St. John's wort on the ischemia/reperfusion injury through various mechanisms, and we are able to suggest that St. John's wort can clinically create a new therapeutic principle.
  • PublicationOpen Access
    Protective Effect of Nigella Sativa Oil Against Indomethacin-Related Small Intestine and Gastric Mucosal Damage in Rats
    (AVES, 2021-04-26) VELİOĞLU ÖĞÜNÇ, AYLİZ; Gunay, Emre; Ozkan, Erkan; Abuoglu, Haci Hasan; Aykac, Asli; Ogunc, Ayliz Velioglu; Karanlik, Buse; Cetinel, Sule; Sehirli, Ahmet Ozer
    BACKGROUND/AIMS The aim of this study was to investigate the effects of Nigella sativa (NS) oil form on reducing the damage caused by indomethacin in the stomach and duodenum of rats owing to their antioxidant and anti-inflammatory properties. MATERIAL and METHODS The rats were divided into 4 groups: group 1, saline-treated control group; group 2, NS-treated control group; group 3, saline-treated ulcer group and ulcers caused by indomethacin (30 mg/kg) and administration of physiological serum; group 4, NS-treated ulcer group, which is the group receiving NS oil after administration of indomethacin. At the end of the study, blood samples collected from animals were examined for tumor necrosis factor alpha (TNF-alpha), interleukin-1 beta (IL-1 beta), and glutathione (GSH), malondialdehyde (MDA) levels and myeloperoxidase (MPO),and Na+/K+-ATPase activities in gastric and intestinal tissue samples. RESULTS Levels of TNF-alpha and IL-1 beta in serum and MDA and MPO values in tissue were found to be higher in the saline-treated ulcer group than in the saline-treated control group. In addition, tissue GSH and Na+/K+-ATPase levels were found to be lower. These values were found to be reversed when comparing NS-treated ulcer group to saline-treated ulcer group. Histopathological findings showed epithelial regeneration and improvement instead of dense tissue damage. CONCLUSION The strong antioxidant and anti-inflammatory effects of NS against potential small intestine and gastric damage were shown using an experimental indomethacin-induced ulcer model in rats. Hence, our study suggests that NS used together with indomethacin can prevent gastrointestinal damage; thus, this agent can create a new clinical therapeutic principle.
  • Publication
    Ginkgo biloba extract ameliorates ischemia reperfusion-induced renal injury in rats
    (ACADEMIC PRESS LTD ELSEVIER SCIENCE LTD, 2005) VELİOĞLU ÖĞÜNÇ, AYLİZ; Sener, G; Sener, E; Sehirli, O; Ogunc, AV; Cetinel, S; Gedik, N; Sakarcan, A
    There is increasing evidence to suggest that reactive oxygen metabolites (ROMs) play a role in the pathogenesis of ischemia/reperfusion injury (I/R) in the kidney. This study was designed to determine the possible protective effect of Ginkgo biloba extract (EGb) on renal ischemia/reperfusion (I/R) injury. Wistar albino rats were unilaterally nephrectomized, and 15 days later they were subjected to 45 min of renal pedicle occlusion followed by 6h of reperfusion. Ginkgo biloba extract (EGb) (50mg kg(-1) day(-1)) or saline was administered twice, 15 min prior to ischemia and immediately before the reperfusion period. At the end of the treatment period, all rats were decapitated. Kidney samples were taken for histological examination or detennination of the renal malondialdehyde (MDA) and glutathione (GSH) levels, myeloperoxidase (MPO) activity and collagen content. Production of reactive oxidants was monitored by chemiluminescence (CL) assay. Creatinine and urea concentrations in blood were measured for the evaluation of renal function. Tumor necrosis factor-alpha (TNF-alpha) and lactate dehydrogenase (LDH) were also assayed in serum samples. Ischemia/reperfusion caused a significant decrease in GSH level, which was accompanied with significant increases in MDA level, MPO activity and collagen content of kidney tissues. Similarly, serum BUN and creatinine levels, as well as LDH and TNF-alpha, were elevated in the I/R group as compared to control group. On the other hand, EGb treatment reversed all these biochemical indices, as well as histopathological alterations, which were induced by I/R. The findings imply that ROMs play a causal role in I/R-induced renal injury and EGb exerts renoprotective effects probably by the radical scavenging and antioxidant activities. (c) 2005 Elsevier Ltd. All rights reserved.
  • Publication
    The Anti-Inflammatory and Neuroprotective Effects of Ghrelin in Subarachnoid Hemorrhage-Induced Oxidative Brain Damage in Rats
    (MARY ANN LIEBERT, INC, 2010) VELİOĞLU ÖĞÜNÇ, AYLİZ; Ersahin, Mehmet; Toklu, Hale Z.; Erzik, Can; Cetinel, Sule; Akakin, Dilek; Velioglu-Ogunc, Ayliz; Tetik, Sermin; Ozdemir, Zarife N.; Sener, Goeksel; Yegen, Berrak C.
    To elucidate the putative neuroprotective effects of ghrelin in subarachnoid hemorrhage (SAH)- induced brain injury, Wistar albino rats (n=54) were divided into sham-operated control, saline-treated SAH, and ghrelin-treated (10 mu g/kg/d IP) SAH groups. The rats were injected with blood (0.3mL) into the cisterna magna to induce SAH, and were sacrificed 48 h after the neurological examination scores were recorded. In plasma samples, neuron-specific enolase (NSE), S-100 beta protein, TNF-alpha, and IL-1 beta levels were evaluated, while forebrain tissue samples were taken for the measurement of malondialdehyde (MDA), glutathione (GSH), reactive oxygen species levels, myeloperoxidase (MPO), Na+-K+-ATPase activity, and DNA fragmentation ratio. Brain tissue samples containing the basilar arteries were obtained for histological examination, while cerebrum and cerebellum were removed for the measurement of blood-brain barrier (BBB) permeability and brain water content. The neurological scores were impaired at 48 h after SAH induction, and SAH caused significant decreases in brain GSH content and Na+-K+-ATPase activity, and increases in chemiluminescence, MDA levels, and MPO activity. Compared with the control group, the protein levels of NSE, S-100 beta, TNF-alpha, and IL-1 beta in plasma were also increased, while ghrelin treatment prevented all SAH-induced alterations observed both biochemically and histopathologically. The results demonstrate that ghrelin alleviates SAH-induced oxidative brain damage, and exerts neuroprotection by maintaining a balance in oxidant-antioxidant status, by inhibiting proinflammatory mediators, and preventing the depletion of endogenous antioxidants evoked by SAH.
  • Publication
    Oxidative renal damage in pyelonephritic rats is ameliorated by montelukast, a selective leukotriene CysLT1 receptor antagonist
    (ELSEVIER SCIENCE BV, 2007) VELİOĞLU ÖĞÜNÇ, AYLİZ; Tugtepe, Halil; Sener, Goksel; Cetinel, Sule; Velioglu-Ogunc, Ayliz; Yegen, Berrak C.
    Urinary tract infections may induce severe inflammation, transient impairment in renal function and scar formation, ranging in severity from acute symptomatic pyelonephritis to chronic pyelonephritis, which have a potential to lead to renal failure and death. The present study aimed to investigate the possible protective effect of montelukast, a selective antagonist of cysteinyl leukotriene receptor I (leukotriene CysLT1), against Escherichia coli-induced oxidative injury and scarring in renal tissue. Wistar rats were injected 0.1 ml of E. coli (ATCC 25922 10(10) cfu/ml) or saline into left renal medullae. Six rats were assigned as the sham group and were given 0.1 ml 0.9% NaCl. Pyelonephritic rats were treated with either saline or montelukast immediately after surgery and at daily intervals. Twenty-four hours or one week after E. coli injection, rats were decapitated and the kidney samples were taken for histological examination or determination of renal malondialdehyde, glutathione (GSH) levels, myeloperoxidase (MPO) activity, and collagen contents. Formation of reactive oxygen species in renal tissue samples was monitored by using chemiluminescence technique with luminol and lucigenin probes. Creatinine, blood urea nitrogen and lactate dehydrogenase (LDH) activity were measured in the serum samples. E. coli inoculation caused significant increases in malondialdehyde level, MPO activity, chemiluminescence levels and collagen content, while GSH level was decreased in the renal tissues (p < 0.05-0.001). On the other hand, serum TNF-alpha, LDH, blood urea nitrogen and serum creatinine levels were elevated in the pyelonephritic rats as compared to control group. Leukotriene CysLT1 receptor antagonist montelukast reversed all these biochemical indices, as well as histopathological alterations, that were induced by acute pyelonephritis. It seems likely that montelukast protects kidney tissue by inhibiting neutrophil infiltration, balancing oxidant-antioxidant status, and regulating the generation of inflammatory mediators suggesting a future role for leukotriene CysLT1 receptor antagonists in the treatment of pyclonephritis. (c) 2006 Elsevier B.V. All rights reserved.