Person: ÖZSAVCI, DERYA
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ÖZSAVCI
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DERYA
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Publication Metadata only Exogenous L-Arginine and HDL Can Alter LDL and ox-LDL-Mediated Platelet Activation: Using Platelet P-Selectin Receptor Numbers(SAGE PUBLICATIONS INC, 2011) ŞENER, AZİZE; Sener, Azize; Enc, Elif; Ozsavci, Derya; Vanizor-Kural, Birgul; Yanikkaya-Demirel, Gulderen; Oba, Rabia; Uras, Fikriye; Demir, MuzafferThe aim of this study is to investigate the effects of exogenous L-arginine and HDL on LDL and oxidized LDL (ox-LDL)-mediated platelet activation. Adenosine diphosphate (ADP)-activated platelets have been incubated with lipoproteins with or without L-arginine. P-selectin receptor numbers per platelet have been measured by flow cytometry. After incubation with only L-arginine (without lipoproteins), platelet nitric oxide (NO) levels and P-selectin receptor numbers significantly increased compared to the controls (P < .05). After incubation with LDL or ox-LDL, receptor numbers of P-selectin significantly increased (P < .001). However, P-selectin receptor numbers in platelets treated with L-arginine + LDL or L-arginine + ox-LDL decreased compared to the levels in platelets treated with only LDL or ox-LDL (P < .01, P < .001, respectively). Addition of HDL to L-arginine + ox-LDL caused significant reduction in P-selectin receptor numbers as in the control values (P < .001). We have concluded that L-arginine causes enhanced platelet NO levels and blocks the effects of LDL or ox-LDL on platelet P-selectin receptor numbers and HDL also strengthens this effect of L-arginine.Publication Metadata only Synthesis of Diflunisal Thiazolidinones as Anticancer Agents(BENTHAM SCIENCE PUBL LTD, 2016) ŞENER, AZİZE; Senkardes, Sevil; Ozakpinar, Ozlem B.; Ozsavci, Derya; Sener, Azize; Cevik, Ozge; Kucukguzel, S. GunizA series of diflunisal 4-thiazolidinones were synthesized. Some selected compounds were determined at one dose towards the full panel of 60 human cancer cell lines by National Cancer Institute. 2',4'-Difluoro-4-hydroxy-N-[4-oxo-2-(thiophen-2-yl)-1,3-thiazolidin-3-yl]biphenyl-3-carboxamide (4a) demonstrated the most marked effect on K-562 cancer cell line with 58.59 % growth inhibition at 10 mu M. Compound 4a was evaluated in vitro using the MTT colorimetric method against human leukemia cell line K-562 and mouse embryonic fibroblasts cell line NIH-3T3 at different doses for cell viability and growth inhibition. Compound 4a exhibited anticancer activity with IC50 value of 5.2 mu M against K-562 cells and did not display cytotoxicity towards NIH-3T3 cells compared with diflunisal. In addition, this compound could be an interesting prototype as an antiproliferative agent.Publication Metadata only Synthesis and antiproliferative evaluation of novel 2-(4H-1,2,4-triazole-3-ylthio)acetamide derivatives as inducers of apoptosis in cancer cells(ELSEVIER FRANCE-EDITIONS SCIENTIFIQUES MEDICALES ELSEVIER, 2016) ÖZSAVCI, DERYA; Kulabas, Necla; Tatar, Esra; Ozakpinar, Ozlem Bingol; Ozsavci, Derya; Pannecouque, Christophe; De Clercq, Erik; Kucukguzel, IlkayIn this study, a series of thiosemicarbazide derivatives 12-14, 1,2,4-triazol-3-thione derivatives 15-17 and compounds bearing 2-(4H-1,2,4-triazole-3-ylthio)acetamide structure 18-32 have been synthesized starting from phenolic compounds such as 2-naphthol, paracetamol and thymol. Structures and purity of the target compounds were confirmed by the use of their chromatographic and spectral data besides microanalysis. All of the synthesized new compounds 12-32 were evaluated for their anti-HIV activity. Among these compounds, three representatives 18, 19 and 25 were selected and evaluated by the National Cancer Institute (NCI) against the full panel of 60 human cancer cell lines derived from nine different cancer types. Antiproliferative effects of the selected compounds were demonstrated in human tumor cell lines K-562, A549 and PC-3. These compounds inhibited cell growth assessed by MTT assay. Compound 18,19 and 25 exhibited anti-cancer activity with IC50 values of 5.96 mu M (PC-3 cells), 7.90 mu M (A549/ATCC cells) and 7.71 mu M (K-562 cells), respectively. After the cell viability assay, caspase activation and Bcl-2 activity of the selected compounds were measured and the loss of mitochondrial membrane potential (MMP) was detected. Compounds 18, 19 and 25 showed a significant increase in caspase-3 activity in a dose-dependent manner. This was not observed for caspase-8 activity with compound 18 and 25, while compound 19 was significantly elevated only at the dose of 50 mu M. In addition, all three compounds significantly decreased the mitochondrial membrane potential and expression of Bcl-2. (C) 2016 Elsevier Masson SAS. All rights reserved.Publication Metadata only Synthesis of Tolmetin Hydrazide-Hydrazones and Discovery of a Potent Apoptosis Inducer in Colon Cancer Cells(WILEY-V C H VERLAG GMBH, 2015) ÖZSAVCI, DERYA; Kucukguzel, S. Guniz; Koc, Derya; Cikla-Suzgun, Pelin; Ozsavci, Derya; Bingol-Ozakpinar, Ozlem; Mega-Tiber, Pinar; Orun, Oya; Erzincan, Pinar; Sag-Erdem, Safiye; Sahin, FikrettinTolmetin hydrazide and a novel series of tolmetin hydrazide-hydrazones 4a-l were synthesized in this study. The structures of the new compounds were determined by spectral (FT-IR, H-1 NMR) methods. N-[(2,6-Dichlorophenyl)methylidene]-2-[1-methyl-5-(4-methylbenzoyl)-1H-pyrrol-2-yl]acetohydrazide (4g) was evaluated in vitro using the MTT colorimetric method against the colon cancer cell lines HCT-116 (ATCC, CCL-247) and HT-29 (ATCC, HTB-38) to determine growth inhibition and cell viability at different doses. Compound 4g exhibited anti-cancer activity with an IC50 value of 76M against colon cancer line HT-29 (ATCC, HTB-38) and did not display cytotoxicity toward control NIH3T3 mouse embryonic fibroblast cells compared to tolmetin. In addition, this compound was evaluated for caspase-3, caspase-8, caspase-9, and annexin-V activation in the apoptotic pathway, which plays a key role in the treatment of cancer. We demonstrated that the anti-cancer activity of this compound was due to the activation of caspase-8 and caspase-9 involved in the apoptotic pathway. In addition, in this study, we investigated the catalytical effect of COX on the HT-29 cancer line, the apoptotic mechanism, and the moleculer binding of tolmetin and compound 4g on the COX enzyme active site.Publication Metadata only Synthesis and Anticancer Activity of Some Novel Tolmetin Thiosemicarbazides(MARMARA UNIV, FAC PHARMACY, 2015) ÖZSAVCI, DERYA; Dadas, Yakup; Coskun, Goknil Pelin; Bingol-Akpinar, Ozlem; Ozsavci, Derya; Kucukguzel, S. GunizA novel series of new ten tolmetin hydrazide derivatives, N-Alkyl/Arylsubstituted-2-{[1-methyl-5-(4-methylbenzoyl)-1H- pyrrol-2-yl]acetyl}hydrazinecarbothioamides [4a-j] have been synthesized in this study. The structures of the new compounds were determined by spectral (FT-IR, H-1-NMR, C-13-NMR and 2D-NMR) methods and their purity were proven by elemental analysis and TLC. Tolmetin [1] and N-(4-fluorophenyl)-2-{[1-methyl-5-(4-methylbenzoyl)-1H-pyrrol-2- yl] acetyl}hydrazinecarbothioamide [4d] were evaluated for in vitro using the MTT colorimetric method for anticancer activity. Androjen-independed human prostate cancer cell line PC-3 (ATCC, CRL-1435), human colon cancer cell lines HCT-116 (ATCC, CCL-247) and HT-29 (ATCC, HTB-38) were used in this study. Compound 4d exhibited anticancer activity against PC-3 whereas Tolmetin showed minor activity comparing to compound 4d.Publication Metadata only Functional and structural changes of the urinary bladder following spinal cord injury; treatment with alpha lipoic acid(WILEY, 2017) VELİOĞLU ÖĞÜNÇ, AYLİZ; Ekiz, Arif; Ozdemir-Kumral, Zarife Nigar; Ersahin, Mehmet; Tugtepe, Halil; Ogunc, Ayliz Velioglu; Akakin, Dilek; Kiran, Demir; Ozsavci, Derya; Biber, Necat; Hakan, Tayfun; Yegen, Berrak C.; Sener, Goksel; Toklu, Hale Z.BACKGROUND & AIMAlpha lipoic acid (LA) was shown to exert neuroprotection in trauma-induced spinal cord injury (SCI), which is frequently associated with urinary bladder complaints in patients with SCI. Accordingly, the protective effects of LA on biochemical and histological changes in bladder as well as functional studies were assessed. METHODSWistar albino rats were divided as control, SCI, and LA (50mg/kg/day, ip) treated SCI groups (SCI+LA). The standard weight-drop (100g/cm force at T10) method was used to induce a moderately severe SCI. One week after the injury, neurological examination was performed and the rats were decapitated. Bladder samples were taken for histological examination, functional (isolated tissue bath) studies, and for the measurement of biochemical parameters (malondialdehyde, MDA; gluthathione, GSH; nerve growth factor, NGF; caspase-3, luminol and lucigenin chemiluminescences). RESULTSSCI caused a significant (P<0.001) increase in the detrusor muscle thickness. It increased the contractility responses to carbachol and relaxation responses to papaverine (P<0.05-0.001). There were also significant alterations in MDA, caspase-3, luminol, and lucigenin chemiluminescences with concomitant decreases in NGF and GSH (P<0.05). LA treatment reversed histological and functional (contraction and relaxation responses) changes induced by SCI (P<0.05-0.001), but no significant recovery was observed in the impaired neurological functions. CONCLUSIONThese results indicate that LA have a beneficial effect in improving the bladder tonus via its antioxidant and anti-inflammatory actions following SCI.Publication Metadata only Flow cytometric assay of platelet glycoprotein receptor numbers in hypercholesterolemia(TAYLOR & FRANCIS INC, 2002) ÖZSAVCI, DERYA; Ozsavci, D; Yardimci, T; Demirel, GY; Demiralp, E; Uras, F; Onder, EIn this study, platelet glycoprotein (Gp) receptor numbers were measured by a flow cytometric assay using Cytoquant Gp in seven hypercholesterolemic and five normal subjects. Thrombin receptor agonist peptide (TRAP) was used to activate platelets. In hypercholesterolemia the Gp receptor numbers per resting platelet were found to be: 38 629 +/- 8538 (GpIIb/IIIa), 22 269 +/- 5628 (GpIb), 37 037 +/- 9810 (GpIIIa), 224 +/- 504 (CD62-P). After activation, receptor numbers were determined to be: 56 399 +/- 9003 (GpIIb/ IIIa), 10 970 +/- 5319 (GpIb), 50 715 +/- 7904 (GpIIIa), 1222 +/- 687 (P-selectin). In the normal group before the activation, receptor numbers were: 43 828 +/- 8862 (GpIIb/ IIIa), 22 166 +/- 3847 (GpIb), 42 351 +/- 1049 (GpIIIa), 62 +/- 139 (CD62-P), After activation, receptor numbers were determined to be: 60 573 +/- 4294 (GpIIb/ IIIa), 13 003 +/- 4118 (GpIb), 52 067 +/- 1039 (GpIIIa), 3608 +/- 1508 (CD62-P). In hypercholesterolemic subjects, GpIIb/ IIIa and GpIIIa receptor numbers on activated platelets increased significantly, whereas P-selectin numbers remained unchanged. However, the GpIb levels decreased significantly. In the control group, after activation, GpIIb/ IIIa and P-selectin receptors increased significantly, GpIIIa receptor numbers did not change significantly, whereas GpIb receptor numbers decreased significantly. When the GpIIb/ IIIa, GpIb, GpIIIa receptor numbers of the control group and hypercholesterolemic group were compared before and after activation, no significant changes were observed (P>0.05). But P-selectin receptor numbers were significantly decreased in hypercholesterolemic patients compared to normals following TRAP activation (P<0.05). In this study, the effect of hypercholesterolemia on platelet function was observed. The striking observation about present study was the marked decrease in P-selectin expression after activation in the hypercholesterolemics compared to normals. This finding suggests some sort of platelet dysfunction in these individuals.Publication Metadata only Melatonin protects against ischemic heart failure in rats(WILEY-BLACKWELL, 2013) ÖZSAVCI, DERYA; Sehirli, Ahmet Ozer; Koyun, Derya; Tetik, Sermin; Ozsavci, Derya; Yiginer, Omer; Cetinel, Sule; Tok, Olgu Enis; Kaya, Zehra; Akkiprik, Mustafa; Kilic, Ertugrul; Sener, GokselIschemic injury, which occurs as a result of sympathetic hyperactivity, plays an important role in heart failure. Melatonin is thought to have antiatherogenic, antioxidant, and vasodilatory effects. In this study, we investigated whether melatonin protects against ischemic heart failure (HF). In Wistar albino rats, HF was induced by left anterior descending (LAD) coronary artery ligation and rats were treated with either vehicle or melatonin (10 mg/kg) for 4 weeks. At the end of this period, echocardiographic measurements were recorded and the rats were decapitated to obtain plasma and cardiac tissue samples. Lactate dehydrogenase, creatine kinase, aspartate aminotransferase, alanine aminotransferase, and lysosomal enzymes (beta-D-glucuronidase, beta-galactosidase, beta-D-N-acetyl-glucosaminidase, acid phosphatase, and cathepsin-D) were studied in plasma samples, while malondialdehyde and glutathione levels and Na+, K+-ATPase, caspase-3 and myeloperoxidase activities were determined in the cardiac samples. Sarco/endoplasmic reticulum calcium ATPase (SERCA) and caveolin-3 levels in cardiac tissues were evaluated using Western blot analyses. Furthermore, caveolin-3 levels were also determined by histological analyses. In the vehicle-treated HF group, cardiotoxicity resulted in decreased cardiac Na+, K+-ATPase and SERCA activities, GSH contents and caveolin-3 levels, while plasma LDH, CK, and lysosomal enzyme activities and cardiac MDA and Myeloperoxidase (MPO) activities were found to be increased. On the other hand, melatonin treatment reversed all the functional and biochemical changes. The present results demonstrate that Mel ameliorates ischemic heart failure in rats. These observations highlight that melatonin is a promising supplement for improving defense mechanisms in the heart against oxidative stress caused by heart failure.Publication Metadata only Synthesis, Cytotoxicity, and Pro-Apoptosis Activity of Etodolac Hydrazide Derivatives as Anticancer Agents(WILEY-V C H VERLAG GMBH, 2013) ŞENER, AZİZE; Cikla, Pelin; Ozsavci, Derya; Bingol-Ozakpinar, Ozlem; Sener, Azize; Cevik, Ozge; Ozbas-Turan, Suna; Akbuga, Julide; Sahin, Fikrettin; Kucukguzel, S. GunizEtodolac hydrazide and a novel series of etodolac hydrazide-hydrazones 315 and etodolac 4-thiazolidinones 1626 were synthesized in this study. The structures of the new compounds were determined by spectral (FT-IR, 1H NMR, 13C NMR, HREI-MS) methods. Some selected compounds were determined at one dose toward the full panel of 60 human cancer cell lines by the National Cancer Institute (NCI, Bethesda, USA). 2-(1,8-Diethyl-1,3,4,9-tetrahydropyrano[3,4-b]indole-1-yl)acetic acid[(4-chlorophenyl)methylene]hydrazide 9 demonstrated the most marked effect on the prostate cancer cell line PC-3, with 58.24% growth inhibition at 105M (10 mu M). Using the MTT colorimetric method, compound 9 was evaluated in vitro against the prostate cell line PC-3 and the rat fibroblast cell line L-929, for cell viability and growth inhibition at different doses. Compound 9 exhibited anticancer activity with an IC50 value of 54 mu M (22.842 mu g/mL) against the PC-3 cells and did not display any cytotoxicity toward the L-929 rat fibroblasts, compared to etodolac. In addition, this compound was evaluated for caspase-3 and Bcl-2 activation in the apoptosis pathway, which plays a key role in the treatment of cancer.Publication Metadata only Do platelet apoptosis, activation, aggregation, lipid peroxidation and platelet-leukocyte aggregate formation occur simultaneously in hyperlipidemia?(PERGAMON-ELSEVIER SCIENCE LTD, 2005) ŞENER, AZİZE; Sener, A; Ozsavci, D; Oba, R; Demirel, Y; Uras, F; Yardimci, KTObjectives: The circulating lipoproteins may cause some abnormalities in platelet composition and function in hypercholesterolemia. The aim Of this Study was to investigate whether platelet apoptosis, platelet activation, platelet aggregation, platelet-leukocyte aggregate (PLA) formation and lipid peroxidation occur simultaneously in hyperlipidemia. Design and methods: Expression of GpIIb/IIIa (CD41a), P-selectin (CD62-P), platelet-bound fibrinogen (antifibrinogen), platelet membrane phosphatidylserine (PS), platelet-monocyte aggregates (mono-PLA) and platelet-neutrophil aggregates (neut-PLA) was measured in eight hyperlipidemic and eight normal subjects using flow cytometry. ADP (10 mu M) was used to activate platelets. Furthermore, ADP induced platelet aggregation responses, platelet malondialdehyde (MDA) and glutathione (GSH) levels were determined. Results: Before platelet activation, platelet CD62-P, anti Fibrinogen, annexin-V, mono-PLA, neut-PLA and platelet MDA levels as well as platelet aggregation responses in the hyperlipidemics were significantly higher than those in the controls (P < 0.01, P < 0.01, P < 0.01, P < 0.001, P < 0.001, P < 0.01, P < 0.001, respectively), whereas GpIIb/IIIa expression and GSH levels were not different significantly (P > 0.05). In the control group, CD62-P, antifibrinogen and annexin-V levels increased significantly after ADP activation (P < 0.05, P < 0.05, P < 0.01, respectively). In hyperlipidemic Subjects, annexin-V expression increased significantly after activation (P < 0.01), whereas expression of GpIIb/ IIIa, CD62-P and anti fibrinogen remained unchanged (P > 0.05). The levels of total cholesterol (T-CHO), low density lipoprotein cholesterol (LDL-C), serum fibrinogen (S-FGN) and high density lipoprotein cholesterol (HDL-C) in patients were found to be correlated with platelet CD62-P, anti Fibrinogen, annexin-V, mono-PLA and MDA. Conclusions: In conclusion, it seems that in hyperlipidemia, some platelets are in an activated state in circulation, and that increased lipid peroxidation, early apoptosis, platelet-leukocytes aggregate formation and platelet aggregation altogether accompany this process. (C) 2005 The Canadian Society of Clinical Chemists. All rights reserved.