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111.
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
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Aysegul Bayramoglu Meral Urhan Kucuk Halıl Ibrahim Guler Okay Abaci Yunus Kucukkaya Ertugrul Colak 《Cytotechnology》2015,67(1):115-122
The current study was conducted to determine whether there is a relation between hypertension and two different polymorphisms, including C1562T of the Matrix metalloproteinase-9 (MMP-9) gene and C677T of the methylenetetrahydrofolate reductase (MTHFR) gene. Genomic DNA obtained from 224 persons (125 patients with hypertension and 99 healthy controls) were used in the study. Polymorphisms were determined by using polymerase chain reaction-restriction fragment length polymorphism and electrophoresis. The results were statistically analyzed and were found to be statistically significant. The frequencies of the C1562T genotypes were found to be, in controls CC 75.8 % and CT 24.2 % and in patients CC 71.2 %, and CT 28.8 %. The frequencies of C677T genotype were found to be, in controls CC 56.6 %, CT 38.4 and TT 5.1 % in controls and in patients CC 52 %, CT 30.4 % and TT 17.6 %. In conclusion, we may suggest that there is no relation between the essential hypertension and C1562T polymorphism of MMP-9 gene; on the other hand C677T polymorphism (genotype TT) of MTHFR gene can be regarded as a genetic indicator for the development of essential hypertension. 相似文献
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Protective Effects of Caffeic Acid Phenethyl Ester on Cyclophosphamide‐Induced Hemorrhagic Cystitis in Rats 下载免费PDF全文
Ersin Uysal H. Ramazan Yılmaz Yunus Ugan Atila Altuntas Atalay Dogru Ali Kutlucan Sevket Ercan Tunc 《Journal of biochemical and molecular toxicology》2015,29(12):559-563
We investigated the protective effect of caffeic acid phenethyl ester (CAPE) on cyclophosphamide‐induced hemorrhagic cystitis in rats in comparison with 2‐mercaptoethane sulfonate (MESNA). Forty male rats were randomized into four groups: group 1 (control), group 2 (cyclophosphamide), group 3 (cyclophosphamide + MESNA), group 4 (cyclophosphamide + CAPE). Cyclophosphamide injection increased malondialdehyde levels indicating oxidative stress, whereas CAPE and MESNA ameliorated malondialdehyde levels in the bladder (p < 0.05). Only catalase activities were decreased significantly in both groups (cyclophosphamide + MESNA and cyclophosphamide + CAPE, p < 0.05). Pretreatment with CAPE (p < 0.01) resulted in a significant decrease in nitric oxide levels when compared with the cyclophosphamide group. When we consider the studies that show the critical importance of increased nitric oxide levels in pathogenesis of cyclophosphamide‐induced hemorrhagic cystitis, we suggest that it would be more beneficial to use MESNA with CAPE to prevent histological damage. 相似文献
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F(ab) fragments imprinted surface plasmon resonance (SPR) chip was prepared for the real-time detection of human immunoglobulin G (IgG). In order to attach polymerization precursor on SPR chip, the SPR chip surface was modified with allyl mercaptan. F(ab) fragments of the IgG molecules were prepared by papain digestion procedure and collected by fast protein liquid chromatography (FPLC) system using Hi-Trap_r Protein A FF column. The collected F(ab) fragments were complexed with histidine containing specific monomer, N-methacryloyl-l-histidine methyl ester (MAH). Molecular imprinted polymeric nanofilm was prepared on SPR chip in the presence of ethylene glycol dimethacrylate and 2-hydroxyethylmethacrylate. The template molecules, F(ab) fragments, were removed from the polymeric nanofilm using 1M NaCl solution (pH: 7.4, phosphate buffer system). The molecular imprinted SPR chip was characterized by contact angle, atomic force microscopy and Fourier transform infrared spectroscopy. By the real-time IgG detection studies carried out using aqueous IgG solutions in different concentrations, the kinetics and isotherm parameters of the molecular imprinted SPR chip-IgG system were calculated. To show selectivity and specificity of the molecular imprinted SPR chip, competitive kinetic analyses were performed using bovine serum albumin (BSA), IgG, F(ab) and F(c) fragments in singular and competitive manner. As last step, IgG detection studies from human plasma were performed and the measured IgG concentrations were well matched with the results determined by enzyme-linked immunosorbent assay (ELISA). The results obtained with the molecular imprinted SPR chip were well fitted to Langmuir isotherm and the detection limit was found as 56 ng/mL. In the light of the results, we can conclude that the proposed molecular imprinted SPR chip can detect IgG molecules from both aqueous solutions and complex natural samples. 相似文献
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The study investigated the effect of feeding regime and sludge age on starch utilization. For this purpose, parallel sequencing batch reactors were operated with pulse and continuous feeding of soluble starch at sludge ages of 8 and 2 days. Pulse feeding induced almost complete conversion of starch to glycogen, while storage was lowered and accompanied with direct growth under continuous feeding, regardless of sludge age. Low sludge age did not alter simultaneous storage and utilization for direct growth but it slightly favoured direct utilization due to faster growing biomass. Experimental results suggested adsorption of starch onto biomass as a preliminary removal mechanism prior to hydrolysis at sludge age of 8 days. Adsorption was not noticeable as substrate removal, glycogen generation and dissolved oxygen decrease were synchronous at sludge age of 2 days. Bacterial community always included fractions storing glycogen although sludge age only affected the relative magnitude of filamentous growth. 相似文献
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The present work proposes the use of Pleurotus ostreatus immobilized on Amberlite XAD-4 as new biosorbent in trace metal determination. The effects of experimental parameters, such as “pH and flow rate of sample solution, amount of solid phase, eluent type, and concentration” on the recovery of the metal ions were investigated. Maximum adsorption of Cr(III), Cd(II) and Cu(II) ions took place in the pH range 4-5. These metal ions can be desorbed with 1 M HCl (recovery 95-100%). 0.2 g adsorbent amount and 2.5 mL min−1 flow rate was found to be optimum of all preconcentration experiments. The sorption capacity after 10 cycles of sorption and desorption does not vary more than 2.0%. The influences of the contaminant ions on the retentions of the analytes were also examined. The results showed that P. ostreatus immobilized on Amberlite XAD-4 can be considered as very promising material in trace metal determination. 相似文献