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Öğe Cardioprotective Effect of Empagliflozin in Rats with IsoproterenolInduced Myocardial Infarction: Evaluation of Lipid Profile, Oxidative Stress, Inflammation, DNA Damage, and Apoptosis(PLEIADES PUBLISHING INC, 2022-11-13) Ekici, Mehmet; Güngör, Hüseyin; Karayiğit, Mehmet Önder; Turgut, Nergiz Hacer; Koçkaya, Mustafa; Karataş, Özhan; Üner, Aykut Göktürk—The antidiabetic drug empagliflozin is reported to have many cardioprotective effects. However, no studies have investigated the protective effects of empagliflozin (EMPA) in isoprenaline (ISO)-induced cardiac oxidative damage-a model mimicking the harmful effects of excess catecholamines on the heart. Therefore, in this study, we aimed to reveal the protective effect of EMPA in isoproterenol ISO-induced myocardial infarction in rats. We induced myocardial infarction by subcutaneously injecting ISO (100 mg/kg). To determine the protective effects of EMPA on the myocardial damage, we administered two different doses (10 and 20 mg/kg) by gavage for 14 days. Here we have shown that a 20 mg/kg dose of EMPA completely rescues rats from myocardial infarction by normalizing the following: elevated ST-segment, increased heart rate, decreased R amplitude, prolongation of the QT interval, and shortened RR interval. In addition, EMPA (20 mg/kg) ameliorates ISO-induced changes in serum cTnI, CK, ischemia-modified albumin (IMA), LDH, AST, ALT levels, and heart index. It improves serum lipid profile by decreasing cholesterol, triglycerides, LDL, and VLDL levels, and by increasing HDL levels. Moreover, EMPA (20 mg/kg) alleviates increased myocardial oxidative stress and inflammation by decreasing MDA, TNF-α, and IL-6 levels and increasing SOD and GPx levels. Furthermore, 20 mg/kg EMPA leads to reductions in DNA damage and apoptosis by downregulating of 8-OHdG and caspase-3 expressions. Collectively, EMPA exerts its protective effects on myocardial damage by improving oxidative stress, apoptosis, lipid profile and oxidative DNA damage in ISO-induced experimental myocardial infarction in rats.Öğe Immunohistochemical expression of MMP–2 and MMP–9 in the brain tissue of sheep naturally infected with Listeria monocytogenes and relationship with cell death in the Listerial encephalitis(2024/10/24) Karayiğit, Mehmet Önder; Halıgür, Mehmet; Ekici, MehmetListeria monocytogenes is an intracellular, food–borne bacterium. Silage is an important source of this pathogen causing listeriosis. Listeriosis is an important health problem for both animals and humans in the world. The disease comprises three clinical syndromes: meningoencephalitis, septicemia and metritis with abortion. Encephalitis is frequently observed and the factors that play a role in its pathogenesis are the subject of research. In this study, the immunohistochemical expression of MMP–2 and MMP–9 together with TUNEL staining was investigated in the pathogenesis of meningoencephalitis in sheep naturally infected with L. monocytogenes. The brains of 25 sheep with Listerial meningoencephalitis were used in this study. Brain material from 10 sheep provided from the slaughterhouse was also used as a control. Tissue sections were stained immunohistochemically with L. monocytogenes, MMP–2 and MMP–9 antibodies. Additionally, TUNEL staining was performed to determine apoptosis in the disease. As a result of the study, it was observed that TUNEL staining in neurons and glial cells, MMP–2 and MMP–9 expressions in vascular endothelial cells, inflammatory cells, microglia and especially neurons in the infected brain tissue were significantly increased compared to controls. These results suggested that MMP–2 and MMP–9 play an active role in the neurodegeneration and cell death that occur in Listerial encephalitis.Öğe Nitric oxide synthase expression in naturally infected sheep brain with listeria monocytogenes and relationship with cell death(Universidade Federal do Rio Grande do Sul, 2018) Karayiğit, Mehmet ÖnderBackground: Nitric oxide is synthesized from L-arginine and catalyzed by a family of NOS. There are three different NOS isoforms: neuronal (nNOS), inducible (iNOS) and endothelial (eNOS). Nitric oxide is an important apoptosis regulator in mammalian system that can induce and prevent apoptosis depending on levels of NO production and environmental conditions of the cell. NOS expression and its relationship with apoptosis has not been well elucidated in listerial meningoencephalitis in sheep. The aim of this study was to investigate eNOS and iNOS expressions in the brain of sheep with natural listeriosis and to compare them with apoptosis which is shaped in the region. Materials, Methods & Results: In the study, formalin fixed and paraffin embedded brainstem tissue from 25 sheep naturally infected with LM were used from archives. Five ?m-thick section was taken from each block. Histopathologically, sections were stained with H&E. Five normal sheep brain tissues were used as control. At the end of the study, Histopathologically in brainstem tissue infected with LM, multifocal microabscesses in different sizes mixed with neutrophils and macrophages were detected and perivascular mononuclear cell infiltration and meningitis characterized by mononuclear cell infiltration were found. All sections were also immunohistochemically stained with LM, eNOS and iNOS antibodies. In addition, TUNEL method was used to determine apoptosis in brain tissues. As a result of immunostaining, listeria immunoreactivity was observed in microabscesses. The Listeria antigens were detected mainly in the cytoplasm of the neutrophils and macrophages and located extracellulary in microabscesses. Both eNOS and iNOS immunoreactivity were observed in very few neurons and glial cells in normal control sheep. Neurons and glial cells in brain tissues of infected animals stained with eNOS and iNOS. But, eNOS and iNOS expressions in listeriosis animals more higher than in control and the this difference was statistically significant (P < 0.05). At the same time, TUNEL immunopositivity was observed mainly in the nuclei of neuron and glial cells and this findings was found to be significantly increased compared to the control group (P < 0.05). Discussion: The pathogenesis of listerial meningoencephalitis depends on many factors and is still a subject of research. NO is a pluripotent regulator of diverse cellular functions. NOS can trigger cellular damage. However, there are studies suggesting that it can prevent oxidative stress. eNOS and iNOS expressions may vary depending on disease and animal species. Increased levels of NO have been reported to induce apoptosis in many diseases. However, there are studies indicating that NO is able to prevent apoptosis according to the isoform in which it is synthesized. eNOS and iNOS have not been reported together expressions and with their relationship apoptosis in sheep brain with listerial meningoencephalitis. This is the first study of eNOS and iNOS expression and and its relation to cell death in sheep brain infected with LM. Our findings are consistent with previous studies suggesting that NO expression is effective on the pathogenesis of some disease in the central nervous system. However, there are studies that do not match the findings of the present study. This suggests that the role of NO synthesis in the pathogenesis of diseases may vary according to the amount of expression, type of disease and tissue, or animal species. In the present study showed that the expression of both eNOS and iNOS with increased TUNEL positive cells was statistically significant in the listeriosis compared the control brain tissue. These results suggests that eNOS and iNOS can be expressed by diverse brain cells in the pathogenesis of listeriosis in sheep. In addition this, synthesis of NO can induce the apoptosis in sheep brain with listerial meningoencephalitis. © 2018 Universidade Federal do Rio Grande do Sul. All rights reserved.Öğe PARVOVİRUS İLE DOĞAL ENFEKTE KÖPEKLERDE MATRİKS METALLOPROTEİNAZ-9 EKSPRESYONU(2018) Karayiğit, Mehmet Önder; Karataş, ÖzhanKöpek parvoviral enteritis 1978 yılında ortaya çıktığındanbu zamana kadar genç köpeklerde yaygın olarakgörülmektedir. Sindirim yolu ile alındıktan sonra sindirimkanalında ve kemik iliğinde mitotik aktivitesi yüksekhücreleri tercih ederek şiddetli kusma, ishal, ateş,dehidrasyon ve halsizliğe sebep olur. MMP’lerembriyonik gelişim, farklılaşma, proliferasyon ve dokurejenerasyonunda önemli rol oynarlar. Bununla birlikteMMP’leri aktive ve kontrol eden faktörler arasında birdengesizlik oluştuğunda bağırsak yangısı, artrit,ateroskleroz veya kanser dahil bir çok hastalık ile sonuçlanır.Önemli olarak, MMP-9'un ekspresyon seviyesibağırsak yangı modellerinde ve Crohn hastalığı veyaülseratif kolit gibi yangısal bağırsak hastalıkları olaninsanlarda daha yüksektir. Bu çalışmanın amacı, MMP9'unparvovirus ile enfekte köpeklerin bağırsak enfeksiyonlarıüzerindeki rolünü araştırmaktır. Bu çalışmada,parvovirus ile doğal enfekte 21 köpek bağırsak dokusuMMP-9 antikoru ile boyandı ve beş adet normal sağlıklıköpek dokusu kontrol olarak kullanıldı. Sonuç olarakparvovirus ile enfekte köpeklerin bağırsak dokularındanMMP-9 ekspresyonu gerçekleşirken kontrol dokulardaekspresyon gözlenmedi. Bu sonuçlar köpeklerdeparvovirüs ile oluşan enteritisin patogenezinde MMP-9ekspresyonunun etkisinin olabileceğini işaret etmektedir.Öğe Ratlarda Deneysel Oluşturulan Yara Modelinde M.Alba Ekstraktının Etkinliğinin Belirlenmesi(Sivas Cumhuriyet University, 2020) Kara, Haki; Şahin, Mahmut; Güngör, Hüseyin; Kumru, Alper Serhat; Yılmaz, Gökhan; Karayiğit, Mehmet ÖnderAntik çağlardan beri bitkiler çeşitli hastalıkların tedavisinde kullanılmaktadırlar. Morus alba da eskiden beri başta diabet olmak üzere karaciğer, dalak, immun sistem ve kardiyovasküler sistem kaynaklı pek çok hastalığın tedavisinde geleneksel olarak kullanılmaktadır. Bu çalışmada Morus albanın yara iyileşmesi üzerindeki etkileri araştırılmıştır. Çalışmada Wistar cinsi erkek ratlarda oluşturulan yara modelinde kontrol, dekspantenol (%2,5 ve %5) ve Morus alba ekstraktı (%2,5 ve %5) uygulanmıştır. Çalışma süresince 3, 6, 9, 12 ve 15. günlerde kaliper ile ölçümler yapılıp 15. Günde ratlar ötanazi edilerek histopatolojik değerlendirmeler yapılmıştır. Elde edilen veriler ışığında Morus Alba ekstraktlarının kontrol ve dekspantenol verilenlere göre daha hızlı yara iyileşmesi hızı sağladığını göstermiştir. Sonuç olarak Morus alba ekstraktının yara iyileşmesinde kullanılabileceği kanaatine varılmıştır.
