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AKBAY, TUĞBA

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AKBAY

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TUĞBA

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Open Access
Effects of Exercise and Calorie Restriction on Brain_x000D_ and Testis in Natural Aging Model
(2021-04-25) YARAT, AYŞEN; Umay HAKGÜDER;Hazal İPEKÇİ;Tuğba TUNALI AKBAY;Ayşen YARAT;Ebru Emekli ALTURFAN;Ünsal Veli ÜSTÜNDAĞ;Burçin ALEV;Nevin GENC KAHRAMAN;Reyhan ÖZÇELİK;Göksel ŞENER
The aim of our study was to examine the effects of exercise and calorie_x000D_ restriction on various tissue damage and antioxidant parameters_x000D_ in the brain and testis of rats in a natural aging model. For this_x000D_ purpose, male Sprague-Dawley rats were the control group (C),_x000D_ the elderly (A), the elderly with calorie restriction (ACR), the elderly_x000D_ who were exercised (AE) and the elderly who were exercised with_x000D_ calorie restriction (ACRE), they were divided into 5 groups. The control_x000D_ group was composed of three-month-old animals. The other_x000D_ group consisted of 15-month-old rats. Exercise and calorie restriction_x000D_ were applied for 6 weeks. At the end of the experiment, lipid_x000D_ peroxidation (LPO), nitric oxide (NO), glutathione (GSH) levels and_x000D_ superoxide dismutase (SOD), catalase (CAT), glutathione-S-transferase_x000D_ (GST) and tissue factor (TF) were determined in brain and_x000D_ testicular tissues homogenates. As a result of the study, the A_x000D_ group’s brain and testis LPO, NO levels and TF activity increased,_x000D_ GSH levels and SOD, CAT and GST activities decreased, when compared_x000D_ to the C group. As a result of our study, an increase in oxidant_x000D_ damage was observed with TF activity in the brain and testis in the_x000D_ natural aging model, and positive effects of exercise and calorie_x000D_ restriction on the antioxidant levels in the brain were determined,_x000D_ especially in aging.
Open Access
Protective effects ofGinkgo biloba extract against mercury(II)-induced cardiovascular oxidative damage in rats
(2007-01) YARAT, AYŞEN; Tunali-Akbay, Tugba; Sener, Goksel; Salvarli, Hanife; Sehirli, Ozer; Yarat, Aysen
Open Access
Antiproliferative activity of whey and casein bioactive peptides on breast cancer: an in vitro and in silico study
(2022-07-01) AKBAY, TUĞBA; Sahna K. O., Cakir B., Tunali-Akbay T.
Bioactive peptides from milk proteins are dietary components with various biological properties and therapeutic effects in a variety of health conditions, including cancer. In this study, the effects of goat milk proteins and bioactive peptides on the MCF-7 breast cancer cell line were investigated. Milk was separated into casein and Whey fractions and treated with either pepsin or trypsin enzymes. Peptides of the hydrolyzed fractions were identified with LC-QTOFF/MS. After identification, the hydrolyzed Whey and casein fractions were incubated with MCF-7 breast cancer cells at various concentrations. The in vitro cytotoxicity of hydrolyzed fractions against MCF-7 cells was tested using MTT assay and flow cytometry analysis. The dead MCF-7 cells were analyzed with LC-Q-TOF/MS. In dead MCF-7 cells, the pyruvate kinase M2, mucin 1-C, glycogen synthase kinase 3-beta, and L-lactate dehydrogenase B were found to be downregulated in the LC-Q-TOF/MS analysis, while receptor-interacting serine/ threonine-protein kinase 1 was found to be up-regulated. These enzymes and mucin-1C also interacted with the milk-derived bioactive peptides in silico. The goat milk bioactive peptides exhibited high binding affinity with these enzymes and mucin-1C. The 5 mu g mL(-1) trypsin-treated casein fraction caused the highest MCF-7 cell death. In conclusion, the bioactive peptides of the pepsin-treated casein fraction and trypsin-treated Whey fraction of goat milk may inhibit the survival of breast cancer cells and exert their effects via multiple mechanisms. The results of this study are novel, suggesting that goat milk-based specific bioactive peptides may have potential as an anti-tumour agent in the treatment of breast cancer.
Open Access
The effect of whey proteins on the brain and small intestine nitric oxide levels: protein profiles in methotrexate-induced oxidative stress
(2022-12-01) ÖZBEYLİ, DİLEK; AKBAY, TUĞBA; YILMAZ KARAOĞLU S., Tufan E., Sivas G. G., Gürel Gökmen B., Dursun E., ÖZBEYLİ D., ŞENER G., AKBAY T.
Objectives: The aim of this study was to determine the effects of whey proteins on methotrexate (MTX)-induced brain and small intestine damage. Materials and Methods: 30 Sprague Dawley rats (200-300 g) were divided into four groups: Control, control + whey, MTX, and MTX+whey. MTX was administered at 20 mg/kg (single dose) intraperitoneally to the MTX group rats, and 2 mg/kg of whey protein were administered by oral gavage for 10 days to the whey groups. Lipid peroxidation, glutathione, and nitric oxide (NO) levels, as well as glutathione-Stransferase and superoxide dismutase activities were measured in the brain and small intestine. SDS-polyacrylamide gel electrophoresis of the brain and intestine tissues were also carried out. Results: While MTX treatment caused oxidative damage in the brain and small intestine, whey protein administration ameliorated MTXinduced oxidative stress. MTX administration did not change the brain’s NO level, while an increase in intestinal NO level was detected. Conclusion: MTX induced oxidative stress in the brain and small intestine changed the protein metabolism in these tissues regardless of reduced food intake. Consecutive 10-day administration of whey proteins has shown its therapeutic effect on MTX-induced brain and small intestine oxidative damage
Open Access
Chard extract increased gastric sialic acid and ameliorated oxidative stress in valproic acid-administered rats
(2023-04-01) ALTURFAN, EBRU IŞIK; AKBAY, TUĞBA; YARAT, AYŞEN; ALEV B., TUNALI S., ÜSTÜNDAĞ Ü. V., İPEKÇİ H., ALTURFAN E. E., AKBAY T. T., YANARDAG R., YARAT A.
Valproic acid, one of the most used drugs for epilepsy patients, has some known side effects. Chard extract has many pharmacological activities. The study aims to evaluate whether valproic acid might interfere with oxidative metabolism in gastric tissue and whether chard ameliorates these effects. The Sprague Dawley rats were divided into four groups (n=8); control, chard-given control, valproic acid, and chard-given valproic acid. The aqueous extracts of chard leaves were given 1 h before the administration of valproic acid for 7 days. On the 8th day, the animals were sacrificed under anesthesia and gastric tissues were homogenized. When compared to the control group, valproic acid significantly increased malondialdehyde and catalase activity, while superoxide dis- mutase activity decreased. Chard administration increased glutathione and, sialic acid levels and decreased malondialdehyde levels and superoxide dismutase activity in the valproic acid group. Based on these findings, since chard increased gastric sialic acid levels, we may suggest that chard may protect gastric mucosa may be through its antioxidant effects.
Open Access
Candida albicans effects the tissue factor activity of blood cells in Type II Diabetes Mellitus
(2015-01-07) YARAT, AYŞEN
Open Access
Edaravone Ameliorates Valproate-Induced Gingival Toxicity by Reducing Oxidative-Stress, Inflammation and Tissue Damage
(MARMARA UNIV, FAC MEDICINE, 2016-05-10) YARAT, AYŞEN; Oktay, Sehkar; Alev, Burcin; Koc Ozturk, Leyla; Tunali, Sevim; Demirel, Sezin; Emekli Alturfan, Ebru; Tunali-Akbay, Tugba; Akyuz, Serap; Yanardag, Refiye; Yarat, Aysen
Valproic acid (2-n-propylpentanoic acid, VPA), the most widely used antiepileptic drug, has potential adverse effects and it can disrupt the oxidant and antioxidant balance. Edaravone (3-methyl-1-phenyl-2-pyrazoline-5-one, EDA) is a potent free radical scavenger. In this study, the effect of EDA on gingiva in VPA induced toxicity was investigated. Female Sprague Dawley rats were randomly divided into four groups: control group, EDA (30 mg/kg/day) given group, VPA (0.5 g/kg/day) given group, and VPA+EDA (in same dose and time) given group. EDA and VPA were given intraperitoneally for seven days. Total protein, lipid peroxidation (LPO), sialic acid (SA) and reduced glutathione (GSH) levels and catalase (CAT), glutathione-S-transferase (GST), glutathione peroxidase (GPx), superoxide dismutase (SOD), myeloperoxidase (MPO), alkaline phosphatase (ALP), acid phosphatase (ACP), sodium potassium ATPase (Na+/K+-ATPase) and tissue factor (TF) activities were determined in gingiva homogenates. The VPA-induced increases were statistically significant for MPO (p<0.01), ACP (p<0.01), Na+/K+-ATPase (p<0.05) and TF (p<0.01) activities, but not for LPO level and ALP activities. EDA treatment markedly blunted all such elevated anomalies. Conclusively, VPA induced oxidative and inflammatory gingival tissue damage, reactions that were appreciably reversed by concurrent administration of EDA.
Open Access
Lactose hydrolyzing activity of the lactase immobilized polycaprolactone and silk fibroin-based nanofiber and nitrocellulose membrane
(2022-10-01) AKBAY, TUĞBA; Yılmaz-Karaoğlu S., Gürel-Gökmen B., AKBAY T.
© 2022 Elsevier LtdThis study aimed to investigate the activity of lactase immobilized polycaprolactone and silk fibroin (PCL/SF)-based nanofiber and nitrocellulose membrane for the preparation of lactose-reduced milk. PCL/SF -based nanofiber was prepared by using the electrospinning method. The lactase enzyme was immobilized using the physical adsorption method on both surfaces, and then the optimum operating temperature and pH of the immobilized enzymes were determined. The efficiency of the immobilized lactase enzyme was determined in both goat and cow milk. The nutrient content of milk was also analyzed before and after the incubation of nanofiber and membrane with milk. The lactose hydrolysis efficiency of the lactase immobilized nitrocellulose membrane was found to be higher than the lactase immobilized PCL/SF -based nanofiber. Lactose was hydrolyzed 59% in cow milk and 87% in goat milk by using lactase immobilized nitrocellulose membrane. 42% of lactose was also hydrolyzed in cow milk and 21% was hydrolyzed in goat milk by using lactase immobilized PCL/SF-based nanofiber. However, the use of these two bioactive surfaces did not change the fat and protein composition of both cow and goat milk. In conclusion, lactase immobilized nitrocellulose membrane was found to be more advantageous in the production of lactose-reduced milk than the lactase immobilized polycaprolactone/silk fibroin nanofiber.
Open Access
Morphological and biochemical investigation of the protective effects of panax ginseng on methotrexate-induced testicular damage
(2023-06-01) AKBAY, TUĞBA; ERCAN, FERİHA; Karakaya F. B., Macit Ç., Sivas G. G., Akbay T., Şeber G., Ercan F.
Objective: Methotrexate (MTX) is a chemotherapeutic agent that causes testicular toxicity used in the cure of various types ofcancer. The anti-oxidant and anti-cancer effects of Panax ginseng (PxG) have been reported in both experimental and clinical studies. This study aims to examine the healing effect of PxG on testicular damage induced by MTX.Materials and Methods: Sprague Dawley male rats (8-week-olds) were used in the study. A single dose ofMTXdissolved in saline(20 mg/kg) was given to MTX and MTX+PxG groups by intraperitoneal injection. PxG dissolved in saline (100 mg/kg) was given by orogastric gavage once a day for 5 days to the MTX+PxG group. Saline was given to the control and MTX groups orally during the experiments. After decapitation, the testis sampleswere obtained. Seminiferous tubules and basement membranewere evaluated histopathologically. Seminiferous tubule diameter and germinal epithelium thickness were measured. Furthermore, oxidative stress parameters such as malondialdehyde, glutathione, superoxide dismutase, and glutathione-S-transferase were measured.Results: MTX treatment caused seminiferous tubule degeneration with a decrease in Johnsen’s score, the seminiferous tubule’sdiameter, and the germinal epithelium’s thickness. Parallel with the histopathological results increased testicular oxidative stress with an increase in malondialdehyde level and a decrease of endogenous anti-oxidant activity with a decrease in glutathione level and glutathione-S-transferase and superoxide dismutase activities. PxG treatment improved these histological and biochemical parameters in MTX-induced testis cytotoxicity.Conclusion: MTX treatment causes testicular damage via the oxidative processes. PxG treatment ameliorates MTX-inducedtesticular damage by inhibiting oxidative stress.
Open Access
Investigation of beta-lactoglobulin derived bioactive peptides against SARS-CoV-2 (COVID-19): In silico analysis
(ELSEVIER, 2021-01) OKUYAN, BETÜL; Cakir, Bilal; Okuyan, Betul; Sener, Goksel; Tunali-Akbay, Tugba
The coronavirus disease of 2019 (COVID-19) outbreak caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which started in late 2019 in Wuhan, China spread to the whole world in a short period of time, and thousands of people have died due to this epidemic. Although scientists have been searching for methods to manage SARS-CoV-2, there is no specific medication against COVID-19 as of yet. Two main approaches should be followed in the treatment of SARS-CoV-2; one of which is to neutralize the virus, and the other is to inhibit the host cell membrane receptors, where SARS-CoV-2 will bind. In this study, peptides derived from beta-lactoglobulin, which inactivates both the virus and its receptors in the host cell, were identified using computer-based in silico analysis. The beta-lactoglobulin derived peptides used in this study were obtained by the treatment of goat milk whey fraction with trypsin. The structure of the peptides was characterized by the liquid chromatography quadrupole time-of-flight mass spectrometry (LC-Q-TOF/MS), and six beta-lactoglobulin derived peptides were selected as candidate peptides. Subsequently, the effects of peptides on SARS-CoV-2 and host cells were identified using virtual screening. According to the results of this in silico analysis, Ala-Leu-Pro-Met-His-Ile-Arg (ALMPHIR) and Ile-Pro-Ala-Val-Phe-Lys (IPAVFK) peptides were evaluated as potential candidates to be used in the treatment of SARS-CoV-2 after the future in vitro and in vivo studies.