Person: YALÇIN, AHMET SUHA
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YALÇIN
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AHMET SUHA
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Publication Metadata only Comparison of antioxidant capacity, protein profile and carbohydrate content of whey protein fractions(ELSEVIER SCI LTD, 2014) YALÇIN, AHMET SUHA; Onay-Ucar, Evren; Arda, Nazli; Pekmez, Murat; Yilmaz, Ayse Mine; Boke-Sarikahya, Nazli; Kirmizigul, Suheyla; Yalcin, A. SuhaWhey is used as an additive in food industry and a dietary supplement in nutrition. Here we report a comparative analysis of antioxidant potential of whey and its fractions. Fractions were obtained by size exclusion chromatography, before and after enzymatic digestion with pepsin or trypsin. Superoxide radical scavenging, lipid peroxidation inhibition and cupric ion reducing activities of different fractions were checked. Peptides were detected by SDS-PAGE and GC-MS was used to determine carbohydrate content of the fractions. All samples showed antioxidant activity and the second fraction of the trypsin hydrolysate showed the highest superoxide radical scavenging activity. CUPRAC value of this fraction was two-times higher than that of whey filtrate. The first fraction of the pepsin hydrolysate was the most effective inhibitor of lipid peroxidation. Each sample exhibited a different polypeptide profile. Different percentages of carbohydrates were identified in whey filtrate and in all second fractions, where galactose was the major component. (C) 2013 Elsevier Ltd. All rights reserved.Publication Metadata only Effect of different culture media on isolation and differentiation of dendritic cells(WALTER DE GRUYTER GMBH, 2015) YALÇIN, AHMET SUHA; Yilmaz, Ayse Mine; Altundag, Ergul Mutlu; Gedik, Gulsah; Kocturk, Semra; Yalcin, A. Suha; Taga, YavuzObjective: Dendritic cells (DCs) are members of the mammalian immune system and are considered to be the most powerful antigen presenting cells. They are responsible for the induction of T-cells or T-cell dependent immunity and tolerance. In this study we have investigated the effect of different serum supplements on generation and yield of mature dendritic cells isolated from peripheral blood mononuclear cells. Methods: Three different serum supplements (10% Fetal Bovine Serum, 1% Human Serum Albumin and 1% autologous serum) were compared with serum-free media to identify the role and importance of serum supplements on DC cultivation. Effect of different media on maturation signs (CD40, CD80, CD86, CD209a) and cytokine release (TNF-alpha, IL-10, IL-12, IL-6) was examined. Results: DCs generated in serum-free media was similar to those of cells in medium with autologous serum. Few dendritic-like cells were observed in fetal bovine serum and human serum albumin. The effect of different media on maturation of DCs was compared phenotypically and increased expression of CD80, CD86 and CD209a identified maturation and yield of DCs. Conclusion: Our results suggest that serum free media can be used to overcome potential drawbacks associated with different serum containing supplements.Publication Metadata only Redox Regulation and Cancer Therapy(BENTHAM SCIENCE PUBL LTD, 2018) YALÇIN, AHMET SUHA; Yalcin, A. Suha; Karademir, BetulPublication Metadata only Dietary whey supplementation in experimental models of wound healing(VERLAG HANS HUBER, 2008) YALÇIN, AHMET SUHA; Ogunc, Ayliz Velioglu; Manukyan, Manuk; Cingi, Asim; Eksioglu-Demiralp, Emel; Aktan, A. Odemir; Yalcin, A. SuhaWhey is a dairy product containing milk serum proteins with diverse biological effects. In this study, the effect of dietary whey supplementation on wound healing was investigated. Rats were fed a standard or whey-supplemented diet for three weeks. Wound healing parameters, glutathione, and lipid peroxide levels were determined three days after the application of two different models of wound healing, i.e. laparotomy and colonic anastomosis. Dietary whey supplementation significantly increased glutathione levels and suppressed lipid peroxidation after experimental laparotomy and colonic anastomosis. Bursting pressures, hydroxyproline, and cytokine levels were not changed. Our results show that dietary whey supplementation increases glutathione synthesis and cellular antioxidant defense. Long-term effects of whey feeding on wound healing remains to be investigated.Publication Metadata only Emerging therapeutic potential of whey proteins and peptides(BENTHAM SCIENCE PUBL LTD, 2006) YALÇIN, AHMET SUHA; Yalcin, A. SuhaWhey is a natural by-product of cheese making process. Bovine milk has about 3.5% protein, 80% of which are caseins and the remaining 20% are whey proteins. Whey proteins contain all the essential amino acids and have the highest protein quality rating among other proteins. Advances in processing technologies have led to the industrial production of different products with varying protein contents from liquid whey. These products have different biological activities and functional properties. Also recent advances in processing technologies have expanded the commercial use of whey proteins and their products. As a result, whey proteins are used as common ingredients in various products including infant formulas, specialized enteral and clinical protein supplements, sports nutrition products, products specific to weight management and mood control. This brief review intends to focus on scientific evidence and recent findings related to the therapeutic potential of whey proteins and peptides.Publication Metadata only Synergistic Induction of Apoptosis by Quercetin and Curcumin in Chronic Myeloid Leukemia (K562) Cells: II. Signal Transduction Pathways Involved(ROUTLEDGE JOURNALS, TAYLOR & FRANCIS LTD, 2021) YALÇIN, AHMET SUHA; Altundag, Ergul Mutlu; Yilmaz, Ayse Mine; Serdar, Belgin Sert; Jannuzzi, Ayse Tarbin; Kocturk, Semra; Yalcin, A. SuhaFlavonoids are phenolic substances with chemo-preventive and chemotherapeutic properties. They are widely found in fruits and vegetables. The polyphenols quercetin and curcumin have antioxidant, anti-inflammatory, anti-carcinogenic, and pro-apoptotic properties. They were successfully used against different human cancers, especially chronic myeloid leukemia cancer cells. We have previously investigated anti-proliferative and apoptotic effects of quercetin and curcumin combination in K562 cells. Our data showed that they had beneficial synergistic effects. Based on these findings, we aimed to clarify signaling pathways involved in synergistic combination treatment with quercetin and curcumin in these cells. Proteins were investigated by Western blotting and by confocal microscopy. Changes in several genes in 10 different pathways related to cell proliferation, apoptosis, cell cycle, inflammation, hypoxia and oxidative stress were observed. Combination of quercetin and curcumin was effective on genes that were particularly related to p53, NF-kappa B and TGF-alpha pathways. Down-regulatory (CDKN1B, AKT1, IFN-gamma) and up-regulatory (BTG2, CDKN1A, FAS) effects on genes and related protein expressions may provide a multi-targeted therapy potential for chronic myeloid leukemia cancer cells without affecting healthy cells.Publication Metadata only Antioxidant activity of whey protein fractions isolated by gel exclusion chromatography an protease treatment(ELSEVIER SCIENCE BV, 2008) YALÇIN, AHMET SUHA; Bayram, Tugba; Pekmez, Murat; Arda, Nazli; Yalcin, A. SuehaWhey proteins were isolated from whey powder by a combination of gel exclusion chromatography and protease (pepsin or trypsin) treatment. Whey solution (6 g/dl) was applied to Sephadex G-200 column chromatography and three fractions were obtained. Gel electrophoresis (SDS-PAGE) was used to identify the fractions; the first one contained immunooglobulins and bovine serum albumin, the second contained P-lactoglobulin and a-lactalbumin whereas the third fraction contained small peptides. We have also subjected the whey filtrate to proteases (pepsin and trypsin). Treatment with proteases showed that P-lactoglobulin can be obtained after hydrolysis of the second fraction with pepsin. When the whey filtrate was treated with pepsin and then applied to Sephadex G-200 column chromatography three fractions were obtained; the first one was bovine serum albumin, the second was beta-lactoglobulin and the third fraction contained small peptides. After trypsin treatment only two fractions were obtained; the first one was serum albumin and the second fraction was an alpha-lactalbumin rich fraction. We have determined the antioxidant activity of the fractions using an assay based on the measurement of superoxide radical scavenging activity. Our results showed that among the three fractions, the first fraction had the highest superoxide radical scavenging activity. Also, protease treatment of the second fraction resulted in an increase in the antioxidant activity. (c) 2007 Elsevier B.V. All rights reserved.Publication Metadata only The potential use of natural products to negate hepatic, renal and neuronal toxicity induced by cancer therapeutics(PERGAMON-ELSEVIER SCIENCE LTD, 2020) YALÇIN, AHMET SUHA; Prsa, Patrik; Karademir, Betul; Bicim, Gokhan; Mahmoud, Hatem; Dahan, Inbal; Yalcin, A. Suha; Mahajna, Jamal; Milisav, IrinaDifferent types of chemotherapeutics are used for cancer treatment. These drugs act on several signal pathways, lead to programmed cell death, and damage cancer cells. Although many specific mechanisms of action have been suggested for chemotherapeutics, there are still gaps in understanding their effects. They may affect different components of the cell, particularly proteins with specific functions, such as enzymes. Recently, targeted and immuno therapies were introduced for treatment of different cancers. However, many cancer patients still depend on traditional and well-known drugs. Doxorubicin and platinum-based drugs are among the most frequently used chemotherapeutics. They are highly cytotoxic for cancer cells, but they also act on healthy cells. Hence, it is crucial to understand the mechanisms involved in order to decrease their side effects. Natural products, many of which are also available over-the-counter, may be considered to decrease various cancer drug-induced side effects. This review focuses on the use of these compounds to overcome side effects of chemotherapeutics, primarily doxorubicin and cisplatin, in the liver, kidney, and neuronal systems.Publication Metadata only Whey Protein Versus Whey Protein Hydrolyzate for the Protection of Azoxymethane and Dextran Sodium Sulfate Induced Colonic Tumors in Rats(SPRINGER, 2012) YALÇIN, AHMET SUHA; Attaallah, Wafi; Yilmaz, Ayse Mine; Erdogan, Nusret; Yalcin, A. Suha; Aktan, A. OzdemirRecent studies have shown that whey protein has many useful effects including its anti-cancer effect. In this study we have compared the protective effect of dietary whey protein with whey protein hydrolyzate against azoxymethane and dextran sodium sulfate induced colon cancer in rats. We used a rat model of the colon cancer induced by administration of azoxymethane followed by repeated dextran sodium sulfate ingestion which causes multiple tumor development. Colon tissues were analyzed histologically in addition to biochemical analyses performed by measuring lipid peroxidation, protein oxidation and glutathione levels in both of colon and liver tissues of rats after sacrification. Macroscopic and microscopic tumors were identified in all groups that received azoxymethane followed by repeated dextran sodium sulfate. Group fed with whey protein hydrolyzate showed significantly less macroscopic and microscopic tumor development compared with group fed with whey protein. The protocol applied to generate an appropriate model of colon cancer was successful. Whey protein hydrolyzate was found to be more effective in preventing colon tumor development compared with whey protein.Publication Metadata only The role of reactive oxygen species and apoptosis in the pathogenesis of varicocele in a rat model and efficiency of vitamin E treatment(WILEY, 2004) YALÇIN, AHMET SUHA; Cam, K; Simsek, F; Yuksel, M; Turker, L; Haklar, G; Yalcin, S; Akdas, AWe investigated role of reactive oxygen species (ROS) and apoptosis in the pathogenesis of infertility in experimental model of varicocele. The protective effect of vitamin E was also examined. Three groups of rats were constructed as the first group had sham operation, experimental varicoceles were established by partial ligation of the left renal vein in later two groups. Third group had received vitamin E. Production of ROS was determined by chemiluminescence assay (CL). The in situ end labelling technique was utilized to investigate apoptosis. Tissue vitamin E levels were measured by high performance liquid chromatography. The differences between luminol enhanced CL levels of groups were not statistically significant. However, the difference between CL levels of lucigenin probe in left testicles of sham and varicocele groups were statistically significant (p = 0.0007). Similarly, the results of the third group receiving vitamin E significantly differed from the varicocele group (p = 0.0025). The difference of apoptotic index was also statistically significant between sham and varicocele groups (p = 0.0038). Although the values of apoptotic index detected in the vitamin E group were lower compared with the varicocele group, the difference was not significant. This study proposes that ROS production and apoptosis in the testicles were induced with experimental varicocele. Vitamin E had a protective role. An increased rate of apoptosis with experimental varicocele suggests a molecular alteration, which may involve ROS overproduction as the triggering mechanism. Consequently, this study indicates an association between varicocele and infertility at molecular level through stimulation of ROS and apoptosis.