Browsing by Author "Yalin, Serap"

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Association Between Pon1 L55m Polymorphism and Pon1 Enzyme Activity in Patients With Leukemia
(Akad Doktorlar Yayinevi, 2017) Eras, Nazan; Tombak, Anil; Tiftik, Naci; Yalin, Serap; Berkoz, Mehmet; Kul, Seval; Akbas, Etem
Paraoxonase 1 (PON1) is an important antioxidant enzyme which has a role in preventing the effects of systemic oxidative stress. The purpose of our study was to investigate the possible association between PON1 L55M polymorphism and leukemia development and to determine the relationship between PON1 genotypes and PON1 enzyme activities. Genotypes of 102 cases and 112 healthy controls were determined by PCR-RFLP. PON1 enzyme activity was determined according to Eckerson's method. The ratio of MM genotype belonging to PON1 L55M polymorphism in control group was 6.3% and was 7.8% in patients with leukemia (p= 0.39). PON1 enzyme activity was 118.8 +/- 115.1 U/mL in control group, while decreased to 75.6 +/- 64.4 U/mL in patients with leukemia (p= 0.004). PON1 enzyme activities of the individuals with MM genotypes belonging to PON1 L55M polymorphism was 57.43 21.61 U/ mL in control group and decreased to 39.18 +/- 45.61 U/mL in leukemic patients. Our results suggest that, PON1 L55M polymorphism genotype ratios do not affect leukemia development. However, reduced PON1 enzyme activity and also the combination of PON1 L55M polymorphism with reduced PON1 enzyme activity are associated with the increased risk of leukemia. Furthermore, older age may be a risk factor for developing leukemia.
Can Juniperus Communis L. Oil Improve Nephropathy in Diabetic Rats
(Marmara Univ, inst Health Sciences, 2020) Kahraman, Tahir; Berkoz, Mehmet; Allahverdiyev, Oruc; Mahmood, Evan Abdulkarim; Yildirim, Metin; Yalin, Serap
Objective: Juniperus communis L. (J. communis) is a shrub belonging to family Cupressaceae L. mainly growth in Eurasia. The antioxidant and antidiabetic activity of aqueous extract of J. communis L. berries indicated benefits as a potent antidiabetic in streptozotocin induced diabetic albino rats. This study was carried out to determine whether J. communis L. oil supplement will effectively manage renal dysfunction in diabetic rats. Methods: Twenty eight rats were divided into 4 equal groups as follows; control group, diabetic group (45 mg/kg, i.p. streptozotocin), J. communis L. oil (200 mg/kg) treated group, and diabetic+J. communis L. oil (200 mg/kg) treated group. At the end of the experimental period, all rats were sacrificed and renal function parameters such as kidney antioxidant and lipid peroxidation markers and serum glucose, HbA1c, creatinine, serum urea, blood urea nitrogen (BUN), and serum total protein levels were measured in all groups. Results: HbA1c, serum glucose, urea, creatinine, BUN and, kidney lipid peroxidation levels increased (p<0.05), but serum total protein and antioxidant levels decreased in diabetic group comparing with control group (p<0.05). Furthermore, HbA1c, serum glucose, urea, creatinine and BUN and, kidney lipid peroxidation levels decreased and also, serum total protein and antioxidant levels increased in diabetic group treated with J. communis L. oil comparing with diabetic group (p<0.05). Conclusion: This study has provided that J. communis L. oil provide a protective effect on the kidney as evidenced by an improvement of the renal function tests as well as reduction in oxidative stress parameters in experimental diabetic nephropathy model.
Effects of Dietary Nucleotide Yeast on Immune Responses and Antioxidant Enzyme Activities of Rainbow Trout Juveniles (Oncorhynchus Mykiss)
(Israeli Journal of Aquaculture-bamidgeh, 2016) Ozluer-Hunt, Arzu; Ozkan-Yilmaz, Ferbal; Berkoz, Mehmet; Engin, Kenan; Gunduz, Suna Gul; Yalin, Serap
This study aimed at demonstrating the effects of dietary supplementation of nucleotide yeast base protein (Nu-Pro (R)) (NP) on the antioxidant enzyme activities and immune response in liver and blood tissues of rainbow trout (Oncorhynchus mykiss). Fish with an average initial weight of 27.75 +/- 0.26 g were randomly assigned to four groups with three replicates. Throughout the 60 day grow-out period the control group was fed a fish meal based basal diet, and three other groups were fed diets in which 20 (NP 20), 40 (NP 40) and 60 % (NP 60) fish meal was substituted with nucleotide (Nu-Pro (NP) yeast). There were no significant changes of superoxide dismutase (SOD) and catalase (CAT) activities in liver among the experimental groups. A significant decrease (P<0.05) in malondialdehyde (MDA) level of tissue was observed in all nucleotide supplemented groups when compared to the control group. Serum lysozyme (LYZ) and myeloperoxidase (MPO) activities and nitric oxide (NO) level of liver tissue were significantly (P<0.05) increased in fish fed with nucleotide yeast based protein diets. The results showed that the fish in all nucleotide supplemented groups showed significantly better antioxidant activity and immune responses.
Effects of Dietary Selenium of Organic Form Against Lead Toxicity on the Antioxidant System in Cyprinus Carpio
(Springer, 2014) Ozkan-Yilmaz, Ferbal; Ozluer-Hunt, Arzu; Gunduz, Suna Gul; Berkoz, Mehmet; Yalin, Serap
In this study was evaluated potential protective effect of organic selenium (Se) on heavy metal stress induced by lead (Pb) in Cyprinus carpio. For this reason, C. carpio was exposed to sublethal concentration of Pb (1.5 mg/L Pb(NO3)(2)) for 14 days. The fish were fed a basal (control; measured 0.55 mg/kg Se) diet or a basal diet supplemented with 2.50 mg/kg (measured 2.92 mg/kg Se) organic Se (Sel-Plex(A (R))) during the experiment period. The variations in glutathione peroxidase (GSH-Px), glutathione S-transferase (GST) activities, and levels of reduced glutathione (GSH) with malondialdehyde (MDA) in liver and brain tissues of C. carpio were investigated in experimental groups. GSH levels in liver and brain tissues were significantly decreased by exposure to Pb. GST activity was significantly increased (p < 0.05) in liver tissue, but decreased in brain of treated fish by exposure to Pb. Also, GSH-Px activity was significantly increased in liver tissue, but decreased in brain of Pb-treated fish. Levels of MDA were increased in liver and brain of Pb-treated fish. The organic Se treatment for Pb-intoxicated animals improved activities of GSH-Px, GST and levels of MDA within normal limits. Supplemented Se could be able to improve Pb-induced oxidative stress by decreasing lipid peroxidation and regulating antioxidant defense system in tissues.
Effects of Fenbutatin Oxide on Antioxidant System of Different Tissues in Cyprinus Carpio (L., 1758)
(Parlar Scientific Publications (p S P), 2017) Ozkan-Yilmaz, Ferbal; Ozluer-Hunt, Arzu; Gunduz, Suna Gul; Berkoz, Mehmet; Yalin, Serap; Yildirim, Metin
In this study, effects of sublethal concentrations of fenbutatin oxide on catalase (CAT) and superoxide dismutase (SOD) activities and lipid peroxidation in muscle, liver, kidney and brain tissues of Cyprinus carpio were investigated. The 96-hours LC50 value for fenbutatin oxide was determined as 1.544 mg/L for C. carpio in this study. 0.15 mg/L (1/10 of LC50) and 0.30 mg/L (1/5 of LC50) sublethal concentrations were applied for 96 h (4 days) in this experiment. The CAT activities in tissues were increased relation to doses applied. The SOD activities were decreased by 0.30 mg/L. The tissue MDA levels were significantly increased in relation to dose applied.
The Effects of Fish Meal Replacement by Yeast Based Nucleotides on Growth, Body Composition and Digestive Enzyme Activity in Rainbow Trout Juveniles (Onchorchyncus Mykiss)
(Israeli Journal of Aquaculture-bamidgeh, 2014) Hunt, Arzu Ozluer; Yilmaz, Ferbal Ozkan; Engin, Kenan; Berkoz, Mehmet; Gunduz, Suna Gul; Yalin, Serap; Sahin, Nefise Ozlen
This 60 day study investigated the effects of organically certified nucleotide yeast-derived protein source (Nu-Pro (R)) on growth, feed efficiency, fillet proximate composition and digestive enzymes in rainbow trout (Onchorhyncus mykiss). Diets were isonitrogenous and isocaloric. Three experimental diets wherein 20%, 40% and 60% of the fish meal content was replaced by Nu-Pro (R), were compared to the control diet in which the crude protein content was anchovy fish meal and corn gluten meal. The rainbow trout (initial weight 27 g/fish) were fed twice daily in 200-l Aqaria. Live weight gain increase ranged from 125-195% in fish fed the experimental diets. Results indicated that up to 40% fish meal protein can be replaced by Nu-Pro (R) without compromising growth rates, feed efficiency or the fillet biochemical composition in the rainbow trout. The effect of the dietary Nu-Pro (R) supplementation on digestion was partly observed by assaying the activity of pepsin, intestinal amylase, trypsin and lipase. Apart from amylase activity, results indicated that dietary supplementation of nucleotides is beneficial and may also have differential effects upon digestive enzyme activities.
Effects of Methidathion on Antioxidant System and Expression of Heat Shock Protein 70 (Hsp70) Gene in the Liver of Oreochromis Niloticus L. 1758
(Parlar Scientific Publications (p S P), 2015) Ozkan-Yilmaz, Ferbal; Ozluer-Hunt, Arzu; Gunduz, Suna Gul; Berkoz, Mehmet; Yalin, Serap; Sahin, Nefise Ozler
In this study, effects of sublethal concentrations of methidathion on catalase (CAT), superoxide dismutase (SOD), glutathion peroxidase (GSH-Px) activities and lipid peroxidation with expression of heat shock protein (HSP70) gene in liver tissues of Oreochromis niloticus were investigated. The 96-h LC50 value for methidathion was determined as 0.1045 mg/L for O. niloticus in this study. 0.013 (1/8 of LC50) and 0.026 mg/L (1/4 of LC50) sublethal concentrations were applied for 4 and 10 days in this experiment. CAT and GSH-Px activities in liver tissue were increased, in relation to both the time and doses applied. SOD activities were increased under the influence of both concentrations at the 4th day, but on 10th day, it was decreased with influence of 0.026 mg/L methidathion concentration. The tissue MDA levels were significantly increased in relation to both the time and dose applied. The relative mRNA levels of the HSP70 gene were detected by real time polymerase chain reaction (RT-PCR). The mRNA levels of HSP70 gene by methidathion increased significantly on 4th days compared to control, but decreased significantly on 10th days.
Influence of Sublethal Chlorpyrifos Exposure on Oxidative Stress and Acetylcholinesterase Activity in Common Carp (Cyprinus Carpio)
(Parlar Scientific Publications (p S P), 2019) Berkoz, Mehmet; Ozkan-Yilmaz, Ferbal; Ozluer-Hunt, Arzu; Gunduz, Suna Gul; Yildirim, Metin; Yalin, Serap
The commonly used pesticides in agriculture cause enzyme inactivation and DNA damage via reacting with macromolecules and may also initiate peroxidation of poly-unsaturated fatty acids (PUFA) by generating of the reactive oxygen species (ROS), as a consequence they can lead to the oxidative stress. The objective of this study was to determine the oxidative and neurotoxic potential of sublethal chlorpyrifos in the brain tissue of Cyprinus carpio (C. carpio) for a period of 96 and 240 hours, respectively. Therefore, the levels of malondialdehyde (MDA), glutathione (GSH), advanced oxidation protein products (AOPP), protein carbonyl, and 8-hydroxydeoxyguanosine (8-OHdG) levels and activities of superoxide dismutase (SOD), catalase, glutathione peroxidase (GSH-Px) and acetylcholinesterase (AChE) were investigated in order to determine the neurotoxic effect in brain tissue of C. carpio exposed to chlorpyrifos. Administration of chlorpyrifos at 0.26 and 0.52 mg/L concentrations caused a significant increase in MDA levels at the 240th hour (p<0.05), the latter concentration increased the GSH level but decreased SOD, GSH-Px, and CAT activities at the 240th hour (p<0.05). Only 0.52 mg/L of chlorpyrifos administration increased protein carbonyl but not AOPP levels at the 240th hour (p<0.05). 0.26 and 0.52 mg/L of chlorpyrifos concentrations caused a significant increase 8-OHdG levels at the 96th and the 240th hours (p<0.05). Chlorpyrifos statistically significantly reduced the AChE levels in both periods and at all administered concentrations (p<0.05). We observed an enhanced oxidative stress and inhibited AChE activity in the brain tissue of C. carpio after exposure to chlorpyrifos. These findings show that sublethal concentration of chloropyrifos leads to significant toxicity in the brain tissues of C. carpio.
Investigation of Effects of Palb2 Genetic Variations on Breast Cancer Predisposition
(Cukurova Univ, Fac Medicine, 2020) Bilen, Muge Yuksel; Berkoz, Mehmet; Yalin, Ali Erdinc; Calikusu, Zuleyha; Eroglu, Pelin; Comelekoglu, Ulku; Yalin, Serap
Purpose: In this study, the effects of three different single nucleotide polymorphisms (rs249954, rs249935, and rs16940342) of partner and localizer of breast cancer gene 2 (PALB2) on breast cancer predisposition have been investigated. Materials and Methods: For this purpose, 150 patients diagnosed to have breast cancer and 150 healthy individuals have been included. By using real time polymerase chain reaction (PCR) method isolated deoxyribonucleic acid (DNA) from each case has been investigated for the PALB2 genetic variations. Results: The distribution of homozygote wild type (AA) and heterozygote (AG) genotypes at rs16940342 polymorphism has been observed to be 44.7% and 55.3% in breast cancer group and 32.7% and 67.3% in control group. The homozygote polymorphic (GG) genotype was not observed in both groups. The discrepancy between the groups in terms of genotype distribution regarding rs16940342 polymorphism has been found statistically significant. However, there was no significant difference in the frequencies of rs249954 and rs249935 polymorphisms comparing both groups. Conclusion: These results show that rs16940342 polymorphism may be an important determinant in terms of breast cancer predisposition in the Turkish population.
Investigation of the Association Between Chronic Hepatitis B and C Infections and Tnf-Α( Gene Polymorphism
(Ankara Microbiology Soc, 2016) Borekci, Gulay; Aras, Nurcan; Kandemir, Ozlem; Yalin, Serap; Celik, Sevim Karakas; Berkoz, Mehmet
Cytokines and genetic factors play important roles in the pathogenesis of chronic hepatitis B (CHB) and chronic hepatitis C (CHC) infections. Variations in cytokine genes may effect the gene expression and may lead to changes in the clinical manifestations of diseases. One of the single nucleotide polymorphisms in the promoter region of tumor necrosis factor-alpha (TNF-alpha) gene is the polymorphism at -308. position which was investigated in many studies by means of its relationship between CHB and CHC infections, however their results are incompatible. Furthermore, there is no sufficient data on this subject in our country. This study was aimed to determine the relationship between TNF-a(-308) gene polymorphism with CHB and CHC infections. A total of 271 patients with chronic hepatitis and 181 healthy subjects were included in the study. Of them 167 were CHB cases (67 female, 100 male; age range 18-74 years, mean age: 40.23 +/- 13.09) and 95 controls for CHB group (46 female, 49 male; mean age: 36.41 +/- 15.0 years), while 104 were CHC cases (63 female, 41 male; age range: 25-79 years, mean age: 52.8 +/- 12.6) and 86 controls for CHC group (41 female, 45 male; mean age: 36.4 +/- 14.9 years). After the isolation of genomic DNA from blood samples of the patient and control groups, TNF-alpha(-308)G/A (rs 1800629) polymorphism was investigated by using the real-time polymerase chain reaction from the obtained DNAs. Among CHB group, TNF-alpha(-308) GG, GA, AA genotypes were detected in 126 (75.4%), 38 (22.8%) and 3 (1.8%) of the patients, respectively, while these numbers were 84 (88.4%), 11 (11.6%) and 0 (0%) in control group, respectively. Among CHC group, TNF-a(-308) GG, GA, AA genotypes were detected in 37 (35.6%), 28 (26.9%) and 39 (37.5%) of the patients, respectively, while these numbers were 38 (44.2%), 8 (9.3%) and 40 (46.5%) in control group, respectively. The frequency of GA genotype was significantly higher in both patient groups compared to the control groups (p=0.024 for CHB and p= 0.006 for CHC). When the distribution of allele frequencies of TNF-alpha(-308)G/A polymorphism was evaluated in the patients and control groups, it was noted that G allele was found to be high in CHB patients comparing with controls (94.2% vs 86.8%), however A allele was identified to be lower than controls (5.8% vs 13.2%) (p= 0.008). In contrast, there was no significant difference in terms of allele frequency compared with CHC patients and the control group (p= 0.969). In conclusion, our data in accordance with the results of many studies in literature, determined that TNF-alpha(-308) polymorphisms can influence the chronicity of hepatitis B and C infections. Further studies on this subject would contribute to the elucidation of the molecular mechanisms of chronic hepatitis B and C diseases.
An Investigation of the Relation Between Catalase C262t Gene Polymorphism and Catalase Enzyme Activity in Leukemia Patients
(Termedia Publishing House Ltd, 2021) Eras, Nazan; Turkoz, Gozde; Tombak, Anil; Tiftik, Naci; Yalin, Serap; Berkoz, Mehmet; Akbas, Etem
Introduction: Catalase (CAT), an antioxidant enzyme, catalyzes conversion of hydrogen peroxide to water and molecular oxygen, protecting cells against oxidative stress. The aim of this study was to investigate the possible association between CAT C262T polymorphism in the promoter region of the CAT gene and leukemia risk and to determine the relationship between CAT genotypes and CAT enzyme activities. Material and methods: Genotypes of 102 cases and 112 healthy controls' genotypes were determined by polymerase chain reaction-restriction fragment length polymorphism methods. Catalase activity was measured with the method of Aebi. Results: The frequencies of the T allele among the cases and controls were 28.4% and 25.9%, respectively (p = 0.75). The frequencies of CC, CT, and TT among cases were 57.8%, 27.4%, and 14.7%, respectively, while in controls, the frequencies of CC, CT, and TT were 54.4%, 39.3%, and 6.3%, respectively, which were not significantly different. Although CAT enzyme activity was lower in leukemia patients with TT genotypes than in controls, this did not reach statistical significance (p = 0.37). Conclusions: This is the first report showing that CAT C262T polymorphism is not a genetic predisposing factor for the risk of leukemia in the Turkish population. However, additional research is needed to confirm these findings.
Myricetin Inhibits Angiotensin Converting Enzyme and Induces Nitric Oxide Production in Huvec Cell Line
(General Physiol and Biophysics, 2020) Berkoz, Mehmet; Yildirim, Metin; Yalin, Serap; Ilhan, Mert; Yunusoglu, Oruc
Nitric oxide is known as relaxing factor because it acts as a vasodilator, increases blood flow, and inhibits platelet aggregation and adhesion, on the other hand nitric oxide can modulate cellular and physiological processes to limit oxidative injury, limiting processes such as leukocyte adhesion. As the complete mechanism of myricetin and its cardiovascular benefits is not completely understood, the aim of this study was to investigate the antihypertensive activity of myricetin in human umbilical vein endothelial cell (HUVEC). Angiotensin converting enzyme (ACE) activity, nitric oxide production, reactive oxygen species (ROS) scavenger activity, cellular calcium concentration, and endothelial nitric oxide synthase (eNOS) activity and protein expression was investigated in HUVEC treated with different concentration of myricetin (1-60 mu M). Myricetin increased nitric oxide production in HUVEC through decreased ROS levels and increased nitric oxide production and eNOS activation. Activation of eNOS enzyme was achieved by an increase of cellular calcium concentration. At the same examined concentration of myricetin, the activity of ACE was significantly inhibited. These findings indicate that myricetin may be helpful for lowering blood pressure; this could be achieved through dietary intervention or by the production of new antihypertensive treatments from a natural product.
Protective Effect of Myricetin, Apigenin, and Hesperidin Pretreatments on Cyclophosphamide-Induced Immunosuppression
(Taylor & Francis Ltd, 2021) Berkoz, Mehmet; Yalin, Serap; Ozkan-Yilmaz, Ferbal; Ozluer-Hunt, Arzu; Krosniak, Miroslaw; Francik, Renata; Yildirim, Metin
Aim: Major side effects of cyclophosphamide administration are immunosuppression and myelosuppression. The immunomodulatory effects of plant bioactive compounds on chemotherapy drug-induced immunosuppression may have significant effects in cancer treatment. For this reason, we investigated the immunomodulatory effect of myricetin, apigenin, and hesperidin in cyclophosphamide-induced immunosuppression in rats. Methods: In our study, a total of 64 rats were used, and divided into eight equal groups. These groups were: control, cyclophosphamide, cyclophosphamide+myricetin (100mg/kg), cyclophosphamide+myricetin (200mg/kg), cyclophosphamide+apigenin (100mg/kg), cyclophosphamide+apigenin (200mg/kg), cyclophosphamide+hesperidin (100mg/kg), and cyclophosphamide+hesperidin (200mg/kg). Myricetin, apigenin, and hesperidin pretreatments were performed for 14d, while cyclophosphamide application (200mg/kg) was performed only on the 4th day of the study. Levels of humoral antibody production, quantitative hemolysis, macrophage phagocytosis, splenic lymphocyte proliferation, and natural killer cell cytotoxicity were determined. In addition, we measured pro-inflammatory cytokines, and followed lipid peroxidation and antioxidant markers and examined the histology of bone marrow, liver and spleen in all groups. Results: During cyclophosphamide treatment, all three phytochemicals increased the levels of humoral antibody production, quantitative hemolysis, macrophage phagocytosis, splenic lymphocyte proliferation, antioxidant markers, and natural killer cell cytotoxicity. Moreover, the agents decreased the levels of pro-inflammatory cytokines and mediators, reduced lipid peroxidation markers, and reduced tissue damage in liver, spleen, and bone marrow. Conclusion: Our study demonstrated that myricetin, apigenin, and hesperidin can reduce the immunosuppressive effect of cyclophosphamide by enhancing both innate and adaptive immune responses, and these compounds may be useful immunomodulatory agents during cancer chemotherapy.
Protective Roles of Some Natural and Synthetic Aromatase Inhibitors in Testicular Insufficiency Caused by Bisphenol a Exposure
(Taylor & Francis Ltd, 2025) Berkoz, Mehmet; Yalin, Serap; Tuerkmen, Omer
In our study, the protective role of synthetic aromatase inhibitors anastrozole (ANS), letrozole (LTZ) and exemestane (EXM) and natural aromatase inhibitors resveratrol (RSV) and apigenin (APG) against testicular failure caused by exposure to Bisphenol A (BPA) was investigated. The epididymal sperm concentration, sperm motility and sperm morphology were determined. Oxidative stress and inflammatory response parameters were examined and histological examinations were performed in testicular tissues. Our results revealed that BPA exposure decreased serum testosterone and estrogen levels, increased FSH and LH levels (p < 0.05). BPA has been found to increase oxidative stress and inflammatory response and disrupt the histological structure. Also, BPA exposure decreased testicular weight, epididymal sperm concentration and motility, and increased abnormal sperm rate (p < 0.05). These results show that ANS, LTZ and RSV treatments reduce the BPA-induced testicular damage.
Thymoquinone Reduces the Inflammatory Response in Adipocytes
(Wiley-blackwell, 2016) Berkoz, Mehmet; Allahverdiyev, Oruc; Yildirim, Metin; Yalin, Serap