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Öğe Apoptotic and cytotoxic effect of origanum minutiflorum on NB2A neuroblastoma cells(University of Ankara, 2020) Sari, Ismail; Donmez Arat, Gonca; Ozkan, Oktay; Aydemir, Isil; Ozbey, Caner; Tu?lu, M. IbrahimObjective: The aim of the present study is to investigate the cytotoxic and apoptotic effects of oregano oil from Origanum minutiflorum, which is an endemic medicinal plant in Turkey, on NB2a neuroblastoma cells. Material and Method: Cell proliferation, apoptosis, and expression of inducible and endothelial nitric oxide synthase have been determined by MTT, TUNEL, and immunohistochemistry, respectively. Result and Discussion: The cell viability was significantly decreased gradually in NB2a cells when the concentrations of both oregano oil and doxorubicin were increased. IC50doses were found to be10.75 ?l/ml for oregano oil and 5?M for doxorubicin. Furthermore, expression of inducible and endothelial nitric oxide synthase, also the number of apoptotic cells was significantly enhanced in NB2a cells after treatment with oregano oil and doxorubicin. There was a remarkable increase in inducible and endothelial nitric oxide synthase expression levels and in the number of apoptotic cells by the dual application of these agents. In addition, oregano oil enhanced the apoptotic effect of doxorubicin. In conclusion, our results indicated that oregano oil of O. minutiflorum has a cytotoxic and apoptotic effect on NB2a cells and these effects may be related to its enhancing effects on inducible and endothelial nitric oxide synthase levels. © 2020 University of Ankara. All rights reserved.Öğe Effect of Oreganum onites L. Aromatic Water Supplemented to Whole Milk on Performance, Blood Metabolites and Oxidative Status of Holstein Calves During the Pre-Weaning Period(Zoological Soc Pakistan, 2023) Ozkaya, Serkan; Ozkan, Oktay; Erbas, Sabri; Yalcin, Isa Gokhan; Piwczynski, Dariusz; Neja, WojciechIn intensive growing systems, the growth and yield of livestock are suppressed due to the oxidative stress to which they are also exposed. In the present study, it was investigated whether Oreganum onites L. aromatic water (OW) could serve as an agent of reducing the effects of oxidative stress while improving the growth performance of suckling Holstein calves. Twenty-eight newborn calves (n=7, in each group) were randomly selected and assigned to the following four treatments: Control, 40, 60 and 80 ml OW supplemented whole milk (WM) per day. The applied 60 and 80 ml OW tended to improve the antioxidative stress mechanism of calves while supporting their growth (e.g., total and daily weight gain, body measurements). The findings of the present study showed that Oreganum onites L. aromatic water, a by-product, can be used safely in alleviating the problems such as oxidative stress that may occur in intensive growing systems.Öğe Effect of supplementing milk replacer with aromatic oregano (Oreganum onites L.) water on performance, immunity and general health profiles of Holstein calves(Csiro Publishing, 2018) Ozkaya, Serkan; Erbas, Sabri; Ozkan, Oktay; Baydar, Hasan; Aksu, TaylanThe purpose of this study was to examine the effects of supplementing milk replacer (MR) with aromatic oregano (Origanum onite L.) water on weaning age, performance during the pre- and post-weaning periods, immune systems, blood parameters and general health of 40 Holstein Friesian calves. The calves fed with oregano water (OW)supplemented MR were weaned earlier than those in the Control group. There were no statistical differences in the liveweight and body measurements among the groups at the weaning age and post-weaning period. The feed intake of the calves fed with OW was higher than that of calves in the Control group in the pre-weaning period. The OW supplementation significantly increased the faecal firmness of calves (P < 0.05). It also decreased the number of E. coli, Coliforms and Enterobacteriaceae pathogens, but only the amount of Enterobacteriaceae was significantly decreased (P < 0.05). Non-pathogens, such as Lactic acid bacteria, were not affected by OW supplementation. The OW supplementation had no significant effect on hematologic and biochemical blood values. There was significant interaction between age and groups in gamma-glutamyl transpeptidase (P < 0.05). The immunoglobulins (IgA, IgG and IgM) values of calves were steadily higher than those of the calves in the Control group. The general health profiles of the calves improved. It can be concluded that MR containing 1-2% OW fed to calves in the early weaning period is a promising treatment to improve their wellbeing and shorten the weaning period.Öğe Effects of Allium tuncelianum on hyperglycemia and oxidative stress in the kidney and liver tissues in rats with diabetes mellitus induced by streptozotocin(Ankara Univ Press, 2019) Atila, Gozde; Bilgili, Ali; Uslu, Hamit; Erdag, Dincer; Ozkan, OktayIn this study, it was aimed to investigate the effects of Allium tuncelianum extract on hyperglycemia and oxidative stress in the kidney and liver tissues in rats with diabetes mellitus induced by streptozotocin. The rats were randomly divided into 4 groups with 10 animals in each group: Control group (C) was intraperitoneally (i.p.) treated with physiological saline solution, diabetic control (DC) group i.p. with a single dose of 50 mg/kg streptozotocin (STZ), diabetic + insulin (D+I) group i.p. with a single dose of 50 mg/kg STZ and subcutaneously (s.c.) with 2 IU insulin for 28 days (Levemir Flexpen), diabetic + Allium tuncelianum extract (D+AT) group i.p. with a single dose of 50 mg/kg STZ and orally with 250 mg/kg Allium tuncelianum extract for 28 days. The serum glycated hemoglobin (HbA1c), insulin levels and the kidney and liver thiobarbituric acid reactive substances (TBARS), superoxide dismutase (SOD), and catalase (CAT) activities were determined by using ELISA kits. Increased blood glucose levels (p<0.001), increased TBARS levels (p<0.001, p<0.01 respectively), and decreased SOD and CAT activities (p<0.001) in the kidney and liver tissue homogenates were determined in diabetic control group compared to control group. Allium tuncelianum extract had potent antioxidant activities in the diabetic rats, and demonstrated improvement effects by increasing insulin levels, decreasing glycated hemoglobin levels, and attenuating oxidative stress in the diabetic rats. This study suggests that Allium tuncelianum extract may have therapeutic potential for patients with diabetes.Öğe In vitro antimicrobial and antibiofilm-forming activities of Origanum munzurense plant extract on some foodborne gram-negative bacteria(Tubitak Scientific & Technological Research Council Turkey, 2023) Yalcin, Halil; Zeybek, Esra; Ozkan, Oktay; Kart, AsimPlants are an important source for the discovery of antimicrobial formulations due to the many biologically active components they contain. In this study, in vitro antimicrobial and antibiofilm forming activities of ethanolic extract of Origanum munzurense were investigated against some strains of foodborne pathogenic bacteria. To investigate the antimicrobial activity, the minimal inhibitory concentration values against the selected bacteria and antibiofilm-forming activity were tested with the liquid microdilution method and microplate method, respectively. MICs of Origanum munzurense extract against the bacteria tested are 32 mg/mL for Escherichia coli O157: H7 ATCC 35150, 32 mg/mL for Escherichia coli O157: H7 ATCC 43895, 16 mg/mL for Salmonella enteritidis ATCC 13076, 16 mg/mL for Salmonella typhimurium ATCC 700408, 32 mg/mL for S. typhimurium ATCC 14028, and 2 mg/mL for Pseudomonas fluorescens ATCC 13525. Origanum munzurense showed the best antibacterial effect on Pseudomonas fluorescens ATCC 13525 strain. The least antibacterial effect was shown on E. coli O157:H7 ATCC 35150, E. coli O157:H7 ATCC 43895, and Salmonella typhimurium ATCC 14028. Origanum munzurense extract inhibited biofilm formation on Salmonella enteritidis ATCC 13076 strain at a concentration of 16 mg/mL. Antibiofilm formation was not observed for other bacteria. Total phenolic content of Origanum munzurense was 539 mg of gallic acid equivalent (GAE)/L. 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging capacity O.of munzurense extract was determined to be 18 & mu;g/L. In conclusion, Origanum munzurense ethanol extract has a range of antibacterial effects on the selected foodborne pathogenic bacteria and showed antibiofilm-forming activity especially for S. enteritidis ATCC 13076. In addition, the plant has the prominent amount of phenolic content with antioxidant and radical scavenging activity.Öğe IN VIVO HEPATOPROTECTIVE EFFECTS OF Hypericum crenulatum BOISS ON NIMESULIDE-INDUCED TOXICITY IN MICE(Parlar Scientific Publications (P S P), 2022) Ozkan, Oktay; Ozbey, Caner; Arat, Gonca Donmez; Kart, Asim; Sari, Ismail; Aydemir, IsilPlants of Hypericaceae family including many species have been used for the treatment of various dieases such as melancholia, abdominal pain, wound, tumor and oxidative stress in folk medicine. Hypericum crenulatum Boiss is a member of this family and is found throughout Bolkar mount from Meydan Yayla to San Tepe. It is an endemic herbaceous perennial plant. It is aimed to investigate in this study whether this plant specie have a hepatoprotective properties against nimesulide-induced liver injury in mice. According to the results of the study, methanolic extract of Hypericum crenulatum Boiss showed significant differences on serum ALP and liver histopathology. However, serum AST and ALT values, TAS, TOS and OSI were not altered. Hypericum crenulatum Boiss significant improvement Boiss extract at low dose provided a in nimesulide-induced acute liver toxicity. The data indicate that methanolic extract of Hypericum crenulatum Boiss is considered to be effective against liver toxicity.Öğe Inhibitory Effect of Valsartan on Pterygium Fibroblasts(Lippincott Williams & Wilkins, 2020) Kucuk, Erkut; Aydemir, Isil; Zor, Kursad Ramazan; Ozkan, OktayPurpose: Angiotensin receptor blockers (ARBs) were shown to have antifibrotic properties in ocular and systemic diseases. In this study, our aim was to investigate the effect of an angiotensin receptor blocker, valsartan, on pterygium fibroblasts and compare this effect with that of mitomycin C (MMC). Methods: Pterygium tissue samples were obtained from 3 patients during surgical excision. Primary cultured pterygium fibroblasts and L929 cell cultures were treated with different concentrations of MMC and valsartan. Results: The cell viability decreased with increasing concentrations of valsartan at 48 hours for both cell types. MMC inhibited the proliferation of both cell types at 48 hours. Both agents significantly decreased the cell migration of the 2 cell types, although it was more prominent in the MMC-treated group. Conclusions: Valsartan inhibited the proliferation and migration of pterygium fibroblasts. The known favorable safety profile of these drugs and the results of this study showing inhibitory effect on pterygium fibroblasts make valsartan a potential therapeutic agent for pterygium treatment.Öğe Investigation of the effects of bisphenol-A exposure on lymphoid system in prenatal stage(Sage Publications Inc, 2020) Aydemir, Isil; Ozbey, Caner; Ozkan, Oktay; Tuglu, Mehmet Ibrahim; Kum, SadiyeBisphenol-A (BPA) used in the production of plastic materials is a temperature-soluble agent. It also has a steroid hormone-like activity; therefore, it poses a danger to human health. In our study, we aimed to investigate the effects of BPA on lymph node and spleen in male rats exposed to this agent during prenatal stage. The pregnant female rats were divided into four groups: control, sham, low dose (300 mu g/kg BPA), and high dose (900 mu g/kg BPA). BPA was dissolved in 1 mL of corn oil and administered to the pregnant rats every day during pregnancy. On the 21st and 45th day after the birth, male rats' lymph node and spleen samples were taken and histopathological examination was performed. Samples were stained with hematoxylin and eosin to determine the general histological appearance, and with CD3 and CD20 immunohistochemically. The results of staining were evaluated by H-score, and statistical analysis was performed. In the samples, BPA applications were not found to cause significant tissue damage. But there was a significant decrease in the immunoreactivities of CD3 and CD20 after BPA applications in both 21st and 45th day samples. After high dose BPA administration, decreased CD3 immunoreactivity was statistically significant. It is thought that BPA does not cause histologically significant tissue damage, but it may impair organ function at cellular level. The investigation of molecules involved in organ function will be useful in revealing the mechanisms that will cause dysfunction.
