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171.
Sahin E Gümüşlü S 《Comparative biochemistry and physiology. Toxicology & pharmacology : CBP》2007,144(4):342-347
We determined the effects of immobilization stress on antioxidant status, protein oxidation and lipid peroxidation in brain, liver, kidney, heart and stomach of rats. Sixteen male Wistar rats (3 months old) were divided into controls (C) and immobilization stress group (IS). IS rats were immobilized for 180 min/day for 15 days. Plasma corticosterone levels were increased in IS group. Copper,zinc-superoxide dismutase activities were increased in brain, liver and kidney, but decreased in the heart and stomach after immobilization. Catalase activities were increased in brain, kidney and heart, and decreased in liver and stomach. Selenium-dependent glutathione peroxidase activities were decreased in brain and kidney, but increased in heart and stomach. Reduced glutathione levels were decreased, while protein carbonyl, conjugated dienes and thiobarbituric acid-reactive substances levels were increased in all tissues. Our results showed that the response of antioxidant defense system to stress differs for each tissue, and protein oxidation and lipid peroxidation is induced by immobilization stress in peripheral tissues. 相似文献
172.
Karakaya Songul Göger Gamze Bona Gülnur Ekşi Yuca Hafize Aydın Bilge Tekman Enes Şahin Aydan Acar Pınar Nur Münevver Güvenalp Zühal 《Protoplasma》2022,259(6):1493-1506
Protoplasma - Colchicum speciosum Steven species is a perennial stemless plant. C. speciosum is a flowering herb native to mountainous regions of northern Turkey, the Caucasus, and northern Iran.... 相似文献
173.
Kuşçu Gökçe Ceren Gürel Çevik Buhur Aylin Oltulu Fatih Akman Levent Köse Timur Yavaşoğlu Nefise Ülkü Karabay Yavaşoğlu Altuğ 《Molecular biology reports》2022,49(3):1721-1729
Molecular Biology Reports - Polycystic ovary syndrome (PCOS) is a metabolic disease that causes infertility due to anovulation in women in reproductive age. It is known that clomiphene citrate (CC)... 相似文献
174.
Üstündağ Fümet Duygu Ünal İsmail Üstündağ Ünsal Veli Cansız Derya Beler Merih Karagöz Atakan Kara Subaşat Hülya Alturfan A. Ata Mega Tiber Pınar Emekli-Alturfan Ebru 《Neurochemical research》2022,47(6):1553-1564
Neurochemical Research - Parkinson’s disease (PD) is one of the most common forms of neurodegenerative diseases and research on potential therapeutic agents for PD continues. Rotenone is a... 相似文献
175.
176.
Kinetic models for the dynamical behavior of polyacrylamide (PAAm)–κ-carrageenan (κC) composite gels
A fluorescence method was employed for studying the drying and swelling of PAAm–κC composite gels, which were formed from acrylamide (AAm) and N, N’- methylenebisacrylamide (BIS) with various κ–carrageenan (κC) contents by free radical crosslinking copolymerization in water. Composite gels were prepared at 80 °C with pyranine (Py) as a fluorescence probe. Scattered light, Isc, and fluorescence emission intensities, Iem, were monitored during drying and swelling of these gels. The fluorescence intensity of pyranine increased and decreased as drying and swelling time are increased, respectively, for all gel samples. The Stern–Volmer equation combined with moving boundary and Li-Tanaka models were used to explain the behavior of Iem during drying and swelling processes respectively. It is found that the desorption coefficient Dd decreased as κC contents were increased for a given temperature during drying. However, the cooperative diffusion coefficient, Ds presented exactly the opposite case. Conventional gravimetrical and volumetric experiments were also carried out during drying and swelling of PAAm–κC composite gels. It was observed that Dd and Ds values measured with the fluorescence method were found to be much larger than they were measured with the conventional methods. 相似文献
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178.
Carbon tetrachloride (CCl4) is widely used to induce liver toxicity in in vitro/in vivo models. Lipid peroxidation (LPO) begins with toxicity and affects cell viability. Recently, the beneficial effects of melatonin and Vitamin D on cell proliferation in human normal and cancer cells were found. This study was planned to evaluate antioxidant and cytoprotective activity of melatonin and Vitamin D in CCl4 induced cytotoxicity in HepG2 and Hep3B hepatoma cell lines. Based on the cytotoxicity assay, melatonin and Vitamin D were evaluated for cytotoprotective potential against CCl4 induced toxicity in HepG2 and Hep3B liver cell lines by monitoring cell viability, LPO and glutathione (GSH) level. Different dosages of CCl4 (0.1, 0.2, 0.3 and 0.4 % v/v) were applied to HepG2 and Hep3B cells in order to determine the most toxic dosage of it in a time dependent manner. The same experiments were repeated with exogenously applied melatonin (MEL) and Vitamin D to groups treated with/without CCL4. Cell viability was determined with MTT measurements at the 2nd, 24th and 48th h. GSH content and Malondialdehyde levels were measured from the cell lysates. As a result, both melatonin and Vitamin D administration during CCl4 exposure protected liver cells from CCl4 induced cell damage. Increase in LPO and decrease in GSH were found in the CCl4 groups of both cells. Contrary to these results administration of MEL and Vitamin D on cells exhibited results similar to the control groups. Therefore, melatonin and Vitamin D might be a promising therapeutic agent in several toxic hepatic diseases. 相似文献
179.
Didem Turgut Coşan Faruk Saydam Cansu Özbayer Fulya Doğaner Ahu Soyocak Hasan Veysi Güneş İrfan Değirmenci Hülyam Kurt Mehmet Cengiz Üstüner Cengiz Bal 《Cytotechnology》2015,67(1):97-105
Hypertension is a major health problem with increasing prevalence around the world. Tannic acid is water-soluble polyphenol that is present in tea, green tea, coffee, red wine, nuts, fruits and many plant foods. It has been reported to serve as an antioxidant or a pro-oxidant depending on the type of cells and its concentration. The purpose of our study was to evaluate the effect of tannic acid on systolic blood pressure, oxidative stress and some urinary parameters in the rat model of essential hypertension. Blood pressures of all rats were measured using the tail-cuff method. The nitric oxide synthase inhibitor N (omega)-nitro-L-arginine was administered orally at a dose of 0.5 g/l/day for 15 days to rats in order to create an animal model of hypertension. Tannic acid was intraperitoneally injected at a dose of 50 mg/kg for 15 days. Superoxide dismutase, catalase activity and the concentration of malondialdehyde (MDA) were determined in blood plasma and homogenates of heart, liver and kidney. In order to evaluate renal functions, urine pH, urine volume, urine creatine, uric acid, and urea nitrogen values were measured. Compared with the hypertension group, a decrease in MDA concentrations of heart tissue (p < 0.01), urea nitrogen values (p < 0.01) and urine volumes (p < 0.001) were established in hypertension + tannic acid group. There was also a decrease in blood pressure values (20th and 30th days) of this group, but there was no a statistical difference according to hypertension group. The findings of our research show the effect of tannic acid in lowering blood pressure in hypertensive rats. 相似文献
180.
The southwestern Carpathians as an ancient centre of diversity of freshwater gammarid amphipods: insights from the Gammarus fossarum species complex
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Gammarus fossarum is a diverse species complex of epigean freshwater amphipods throughout Europe. Due to their poor dispersal capabilities and ubiquity, these crustaceans may serve as a model for investigating the influence of historical factors on the contemporary distribution and diversity patterns of freshwater macrozoobenthos. Here, we investigate the fine‐scale phylogeographic structure of this complex across its range in the southwestern Carpathian Mountains, which comprises two areas that are geographically isolated from its main European distribution area as well as from each other. Given the Tertiary age of many freshwater Gammarus species, we hypothesize that the southwestern Carpathian populations reflect a relict distribution pattern. We used two mitochondrial and three nuclear markers from 32 localities to reconstruct phylogenetic relationships and estimate the timings of divergence among southwestern Carpathian and non‐Carpathian lineages. Cryptic diversity was evaluated from mitochondrial markers by employing phylogenetic and distance‐based methods. We distinguished at least 16 cryptic microendemic taxa, some of them coexisting, distributed in the southwestern Carpathians in a mosaic‐like pattern. These lineages form a monophyletic group together with several lineages from southeastern Europe. Estimated divergence times indicate a Middle Miocene origin of this clade, with many deep splits dating back to more than 10 Ma. This time frame corresponds with a period of intense geological subsidence in the region that gave birth to the Pannonian Basin. We conclude that subsidence could have been an important driver of diversification in freshwater Gammarus and that the southwestern Carpathians represent an ancient centre of diversity for these crustaceans. 相似文献