Browsing by Author "Özerkan D."
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Scopus CHARACTERIZATION AND ISOLATION OF VERY SMALL EMBRYONIC-LIKE (VSEL) STEM CELLS OBTAINED FROM HUMAN PERIPHERAL BLOOD(2019-01-01) Erdem Kuruca S.; Çelik D.D.; Demirel G.; Özerkan D.Objective: Stem cell transplantation is considered to be one of the available treatments for malign or hereditary blood diseases and bone marrow failure. Peripheral blood progenitor cells (PBPC) are widely used for this technique. Recently a new type of stem cell with a pluripotent potential has been identified. These cells, called very small embryonic-like (VSEL) stem cells, are thought to be found in peripheral blood (PB) in adult individuals. The aim of this study was to obtain and identify VSEL stem cells using a peripheral blood source. Material and Method: VSEL cells were isolated from mononuclear and erythrocyte layers obtained by using lysis and ficoll gradient methods from the materials taken from donors. The presence of NANOG, OCT4, SSEA-4 and CXCR-4 embryonal stem cell markers by flow cytometry and immunofluorescence staining was investigated. The presence of NANOG and OCT4 proteins was investigated using the Western blot method. Results: According to the flow cytometry results, the number of cells carrying the VSEL marker was higher in the debris layer than in the CD45-population. Western and immunofluorescence results showed high levels of OCT4 and NANOG expression. It was also determined that these proteins are present in both the cytoplasm and the nucleus. Conclusions: High expression of these proteins, known as pluripotent stem cell markers, in adult peripheral blood brings to mind the question of how they work in differentiated tissues. These findings strengthen the thesis of a new stem cell population that have pluripotent markers in peripheral blood and provide the basis for future clinical studies about this point.Scopus Characterization and Isolation of Very Small Embryonic-like (VSEL) Stem Cells Obtained from Various Human Hematopoietic Cell Sources(2019-10-01) Kuruca S.E.; Çelik D.D.; Özerkan D.; Erdemir G.Stem cell transplantation is one of the available treatments for leukemia, lymphoma, hereditary blood diseases and bone marrow failure. Bone marrow (BM), peripheral blood progenitor cells (PBPC), and cord blood (CB) are the predominant sources of stem cells. Recently a new type of stem cell with a pluripotent potential has been identified. These cells were named “very small embryonic like stem cells (VSELs)”. It is claimed that VSEL stem cells can be found in adult BM, peripheral blood (PB), CB and other body tissues. This study is designed to characterize and isolate VSEL stem cells from different human hematopoietic sources; CB, PB and apheresis material (PBPC). VSEL stem cells were isolated from MNC and erythrocyte layers for all materials by using centrifugation and ficoll gradient method. We determined embryonic markers by flow cytometry, immunofluorescence and western blotting methods. Results from western blotting and immunofluorescence show high level of NANOG and OCT4 protein expression in PB, apheresis material and CB. Immunofluorescence images showed cytoplasmic and nuclear presence of these proteins. Flow cytometry results exhibited a higher expression of VSELs markers on debris area than CD45- population and higher expression on CB than PB. As a result, these findings have shown that it is necessary to investigate the function of pluripotent stem cell markers in differentiated adult cells. We further conclude that erythrocyte lysis method had the highest cell recovery amount among erythrocyte lysis and ficoll gradient methods. Consequently, this study gives us new information and viewpoints about expression of pluripotent stem cell (PSC) markers in adult tissues.Scopus Comparison of Selenic Acid and Pyruvic Acid-Loaded Silver Nanocarriers Impact on Colorectal Cancer Viability(2023-01-01) Erdemir G.; Danişman-Kalindemirtaş F.; Kariper İ.A.; Kuruca D.S.; Özerkan D.Scopus Novel palladium (II) complexes with tetradentate thiosemicarbazones. Synthesis, characterization, in vitro cytotoxicity and xanthine oxidase inhibition(2019-12-01) Özerkan D.; Ertik O.; Kaya B.; Kuruca S.E.; Yanardag R.; Ülküseven B.In vitro cytotoxicity and xanthine oxidase inhibition capabilities were investigated for five palladium (II) chelate complexes. The palladium complexes were synthesized by starting from S-alkyl-thiosemicarbazones where the alkyl component is methyl, ethyl, propyl or butyl. The solid complexes are characterized by elemental analysis and spectroscopic techniques (UV-visible, IR and 1H NMR). In order to be able to verify the N2O2-type thiosemicarbazidato ligand (L2−) structure in the square planar geometry, complex 1 has been studied as a representative by using single crystal X-ray crystallography. The in vitro cytotoxic activity measurements were carried out in HepG2 and Hep3B hepatocellular carcinomas, HCT116 colorectal carcinoma, and 3 T3 mouse fibroblast cell lines. The palladium complexes exhibited notable cytotoxic activities in all cell lines at lower μM concentrations compared to the standard chemicals, cisplatin and allopurinol. IC50 values were determined between 0.42 ± 0.01 and 12.01 ± 0.37 μg/ml in examining the antixanthine oxidase abilities of the complexes. Two complexes with S-methyl group exhibited a high inhibition activity on the xanthine oxidase. The results indicated that these complexes could be used as active pharmaceutical ingredients.Scopus Protective effects of cytokine combinations against the apoptotic activity of glucocorticoids on CD34 + hematopoietic stem/progenitor cells(2019-02-15) Erdem Kuruca S.; Çetin M.B.; Akgün Dar K.; Özerkan D.Haematopoietic stem cells can self-renew and produce progenitor cells, which have a high proliferation capacity. Chemotherapeutic drugs are toxic to normal cells as well as cancer cells, and glucocorticoids (GCs), which are essential drugs for many chemotherapeutic protocols, efficiently induce apoptosis not only in malignant cells but also in normal haematopoietic cells. Studies have shown that haematopoietic cytokines can prevent the apoptosis induced by chemotherapy and decrease the toxic effects of these drugs. However, the apoptosis induction mechanism of GCs in CD34 + haematopoietic cells and the anti-apoptotic effects of cytokines have not been well elucidated. In this study, we investigated the apoptotic effects of GCs on CD34 + , a haematopoietic stem/progenitor cell (HSPC) population, and demonstrated the protective effects of haematopoietic cytokines. We used a cytokine cocktail containing early-acting cytokines, namely, interleukin-3 (IL-3), thrombopoietin, stem cell factor and flt3/flk2 ligand, and dexamethasone and prednisolone were used as GCs. Apoptotic mechanisms were assessed by immunohistochemical staining and quantified using H-scoring. Dexamethasone and prednisolone induced apoptosis in CD34 + HSPCs. GC treatment caused a significant increase in apoptotic Fas, caspase-3, cytochrome c and Bax, but a significant decrease in anti-apoptotic Bcl-2. Furthermore, as expected, cytokines caused a significant decrease in all apoptotic markers and a significant increase in Bcl-2. Thus, our findings suggest that CD34 + HSPCs are an extremely sensitive target for GCs and that cytokines protect these cells from GC-induced apoptosis.Scopus Some Bryophytes Trigger Cytotoxicity of Stem Cell-like Population in 5-Fluorouracil Resistant Colon Cancer Cells(2022-01-01) Özerkan D.; Erol A.; Altuner E.M.; Canlı K.; Kuruca D.S.Colorectal cancer is the third most common cancer worldwide. Cancer stem cells are known to play an important role in relapse, and metastases of the disease after chemotherapy. Investigation of new drugs, and their combinations targeting these cells and thus eliminating cancer is one of the most urgent needs of today’s chemotherapy. The aim of the present study was to evaluate the effects of Bryophytes like Abietinella abietina (AA), Homolothecium sericeum (HS), Tortella tortuosa (TT), Syntrichia ruralis (SR), and Bryoerythrophyllum rubrum (BR) species extracted with ethyl alcohol on 5-fluorouracil(5-FU) resistant colorectal cancer cell lines (HCT116 and HT29). After extraction, stock solutions of bryophytes were prepared, and IC50 values were detected in drug-resistant cells obtained with 5-FU application. CD24+, CD44+/CD133+ surface markers and P‐glycoprotein (P-gp) mediated efflux were isolated from both 5-FU treated cells and analyzed using the flow cytometry. In all bryophyte-treated groups, the binding Rho123low (low Rho fluorescence) and Rhohigh (high Rho fluorescence) were sorted from 5-FU resistant HCT116, and HT-29 cells. All types of bryophytes were found cytotoxic. Bryophyte extract reduced the percentage of Rholow cells in cultures incubated with 5-FU. In summary, the implementation of these bryophytes might be regarded as an effective approach for treatment of colorectal cancer due to their cytotoxic effect that decreases the recurrence of the disease. Supplemental data for this article is available online at https://doi.org/10.1080/01635581.2021.1933098.Scopus Synthesis and Anticancerogenic Effect of New Generation Ruthenium-Based Nanoparticle from Homalothecium sericeum with Eco-Friendly Method(2023-01-01) Samir N.; Özerkan D.; Danışman-Kalındemirtaş F.; Kariper İ.A.; Bulut H.; Kuruca D.S.; Altuner E.M.; Ulukaya E.Background: Green synthesis is a simple, inexpensive, and highly efficient method for the preparation of nanoparticles. In this study, ethanol extracts of Homalothecium sericeum (HOM) moss were used as reducing agents for the synthesis of biocompatible ruthenium nanoparticles (RuNPs). The ruthenium-based green synthesis method has not been used in any other work in the literature. UV–visible spectrophotometer (UV–Vis), Zetasizer, FTIR, and EDX-SEM were used to characterize the RuNPs synthesized by the green synthesis method, and their efficacy on cell viability was tested on HCT116 human colon cancer cells. Methods: UV spectroscopic measurements were used to study the release of HOM-RuNPs. Apoptosis was assessed by measuring protein expression of p53, Bax, and Bcl-2 by Western blotting. The presence of apoptosis was confirmed by double staining with Hoechst dye/propidium iodide under a fluorescence microscope. HOM-RuNPs were also tested for BCRP/ABCG2 expression to check for drug resistance. Results: HOM-RuNPs with a size of 70–80 nm were found to be most effective at a dosage of 5.71 µg/ml and induced cell death by increasing the ratio of Bax/Bcl-2 and p53 expression. It was also shown to reduce multidrug resistance protein (ABCG2), suggesting that it may be useful against multidrug resistance. Conclusion: Ruthenium-based nanoparticles synthesized by a green synthesis technique may be a candidate for anticancer drugs in the pharmaceutical industry and deserve further attention for proof-of-concept studies.Scopus The Determination of Cisplatin and Luteolin Synergistic Effect on Colorectal Cancer Cell Apoptosis and Mitochondrial Dysfunction by Fluorescence Labelling(2023-01-01) Özerkan D.Despite the initial success of chemotherapy in the treatment of colorectal carcinoma (CRC), the recurrence of the disease shows that the tumor response is limited by the formation of drug resistance and cannot be kept under control. These drawbacks are associated with the cytostatic chemotherapeutic agent cisplatin (Cis). Combination treatment with different anticancer drugs could increase the therapeutic efficacy of combined therapies by allowing the use of lower, less toxic doses to achieve more efficient destruction of cancer cells. Luteolin (LU) has been studied with other anticancer drugs due to its anticancer cell inhibitory properties and has been shown to sensitize the cytotoxicity induced by various anticancer drugs in several cancer cells. Therefore, in this work, the CompuSyn system was used to investigate different Cis + LU combinations in HCT116 colorectal cancer cells. Immunofluorescence was used to measure mitochondrial membrane potential (MMP) and cell death. As a result, a synergistic effect was observed in 5 of the 7 doses tested. Apoptosis/necrosis resulting from chemotherapy resistance was confirmed by Hoechst/ PI -double staining and mitochondrial dysfunction were determined by Rodamine123 (Rho123). Luteolin could thus be used in medicine to provide more effective cancer therapy in appropriate doses, which promises a promising future in clinical application.Publication The Determination of Cisplatin and Luteolin Synergistic Effect on Colorectal Cancer Cell Apoptosis and Mitochondrial Dysfunction by Fluorescence Labelling.(2023-01-18T00:00:00Z) Özerkan, Dilşad; Ozerkan, DDespite the initial success of chemotherapy in the treatment of colorectal carcinoma (CRC), the recurrence of the disease shows that the tumor response is limited by the formation of drug resistance and cannot be kept under control. These drawbacks are associated with the cytostatic chemotherapeutic agent cisplatin (Cis). Combination treatment with different anticancer drugs could increase the therapeutic efficacy of combined therapies by allowing the use of lower, less toxic doses to achieve more efficient destruction of cancer cells. Luteolin (LU) has been studied with other anticancer drugs due to its anticancer cell inhibitory properties and has been shown to sensitize the cytotoxicity induced by various anticancer drugs in several cancer cells. Therefore, in this work, the CompuSyn system was used to investigate different Cis + LU combinations in HCT116 colorectal cancer cells. Immunofluorescence was used to measure mitochondrial membrane potential (MMP) and cell death. As a result, a synergistic effect was observed in 5 of the 7 doses tested. Apoptosis/necrosis resulting from chemotherapy resistance was confirmed by Hoechst/ PI -double staining and mitochondrial dysfunction were determined by Rodamine123 (Rho123). Luteolin could thus be used in medicine to provide more effective cancer therapy in appropriate doses, which promises a promising future in clinical application.Scopus The Novel 5-Fluorouracil Loaded Ruthenium-based Nanocarriers Enhanced Anticancer and Apoptotic Efficiency while Reducing Multidrug Resistance in Colorectal Cancer Cells(2023-01-01) Danişman-Kalindemirtaş F.; Özerkan D.; Kariper İ.A.; Bulut H.Recently, nanocarriers have been made to eliminate the disadvantages of chemotherapeutic agents by nanocarriers. Nanocarriers show their efficacy through their targeted and controlled release. In this study, 5-fluorouracil (5FU) was loaded into ruthenium (Ru)-based nanocarrier (5FU-RuNPs) for the first time to eliminate the disadvantages of 5FU, and its cytotoxic and apoptotic effects on HCT116 colorectal cancer cells were compared with free 5FU. 5FU-RuNPs with a size of approximately 100 nm showed a 2.61-fold higher cytotoxic effect compared to free 5FU. Apoptotic cells were detected by Hoechst/propidium iodide double staining, and the expression levels of BAX/Bcl-2 and p53 proteins, in which apoptosis occurred intrinsically, were revealed. In addition, 5FU-RuNPs was also found to reduce multidrug resistance (MDR) according to BCRP/ABCG2 gene expression levels. When all the results were evaluated, the fact that Ru-based nanocarriers alone did not cause cytotoxicity proved that they were ideal nanocarriers. Moreover, 5FU-RuNPs did not show any significant effect on the cell viability of normal human epithelial cell lines BEAS-2B. Consequently, the 5FU-RuNPs synthesized for the first time may be ideal candidates for cancer treatment because they can minimize the potential drawbacks of free 5FU.Scopus The protective effect of vitamin D against carbon tetrachloride damage to the rat liver(2017-10-03) Özerkan D.; Özsoy N.; Akbulut K.G.; Güney; Öztürk G.We investigated the protective effect of vitamin D against liver damage caused by carbon tetrachloride (CCl4). Twenty-four male rats were divided into four equal groups: G1, untreated controls; G2, administered CCl4; G3, administered both CCl4 and vitamin D for 10 weeks; G4, administered CCl4 for 10 weeks and vitamin D for 12 weeks. At the end of experiment, intracardiac blood samples were taken and liver samples were removed. Hepatic damage due to CCl4 was assessed using biochemistry and histopathology. Glutathione (GSH) levels decreased, while malondialdehyde (MDA) levels increased in liver tissues of G2. Alanine transaminase (ALT), alkaline phosphatase (ALP), and gamma-glutamyl-transaminase (GGT) levels increased, while albumin (ALB) levels decreased. Hepatocyte degeneration, lobular disorder, sinusoid dilation, focal necrotic areas, hyperemia, and glycogen loss were observed. Hepatic fibrosis was observed around portal areas and central veins. Bridging fibrous septa were formed between portal veins. By immunohistochemistry, both matrix metalloproteinase-9 (MMP-9) and desmin reactivity were increased. All aspects of liver damage were at least partially prevented in rats treated with vitamin D. Vitamin D appears to act as an antioxidant and anti-fibrotic to protect the rat liver against damage.Scopus Vitamin D and melatonin protect the cell’s viability and ameliorate the CCl4 induced cytotoxicity in HepG2 and Hep3B hepatoma cell lines(2014-07-06) Özerkan D.; Özsoy N.; Yılmaz E.Carbon tetrachloride (CCl4) is widely used to induce liver toxicity in in vitro/in vivo models. Lipid peroxidation (LPO) begins with toxicity and affects cell viability. Recently, the beneficial effects of melatonin and Vitamin D on cell proliferation in human normal and cancer cells were found. This study was planned to evaluate antioxidant and cytoprotective activity of melatonin and Vitamin D in CCl4 induced cytotoxicity in HepG2 and Hep3B hepatoma cell lines. Based on the cytotoxicity assay, melatonin and Vitamin D were evaluated for cytotoprotective potential against CCl4 induced toxicity in HepG2 and Hep3B liver cell lines by monitoring cell viability, LPO and glutathione (GSH) level. Different dosages of CCl4 (0.1, 0.2, 0.3 and 0.4 % v/v) were applied to HepG2 and Hep3B cells in order to determine the most toxic dosage of it in a time dependent manner. The same experiments were repeated with exogenously applied melatonin (MEL) and Vitamin D to groups treated with/without CCL4. Cell viability was determined with MTT measurements at the 2nd, 24th and 48th h. GSH content and Malondialdehyde levels were measured from the cell lysates. As a result, both melatonin and Vitamin D administration during CCl4 exposure protected liver cells from CCl4 induced cell damage. Increase in LPO and decrease in GSH were found in the CCl4 groups of both cells. Contrary to these results administration of MEL and Vitamin D on cells exhibited results similar to the control groups. Therefore, melatonin and Vitamin D might be a promising therapeutic agent in several toxic hepatic diseases.