Hassan Fazelinejad; Nayyereh Keighobadi
Abstract
One of the main features of neurodegenerative disorders such as Alzheimer's disease (AD) is the amyloid aggregation of specific proteins in the brain tissue. Inhibition of protein misfolding and aggregation is results of utmost importance in the prevention and treatment of such diseases. In the experimental ...
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One of the main features of neurodegenerative disorders such as Alzheimer's disease (AD) is the amyloid aggregation of specific proteins in the brain tissue. Inhibition of protein misfolding and aggregation is results of utmost importance in the prevention and treatment of such diseases. In the experimental present study the possible effects of Portulaca oleracea extract on amyloid fibrillation of hen egg white lysozyme (HEWL) as a protein model and possible its role in treatment of amyloidosis diseases were explored. Lysozymal amyloid was prepared in the harsh condition such as acidic pH and high temperature and confirmed by various techniques including Congo red (CR), Thioflavin T (ThT) binding assays and atomic force microscopy. Data were analyzed through SPSS 16 using descriptive statistics as well as independent t-test. The collected and dried Portulaca oleracea was first dechlorophyllized and then its hydroalcoholic extract was obtained. The extract was concentrated and dried for 48 h, then stored at -20º. This studies by ThT showed that, amyloid formation in the presence of Portulaca oleracea extract significantly (p˂0.05) in a concentration-dependent manner was inhibited. The Amyloid formation inhibition in presence of the extract also were confirmed by Congo red assay and AFM images. Both Intrinsic and ANS fluorescence showed that inhibition effect of the extract is not due to stabilization of native structure of the protein. The results suggested that aromatic compounds in the extract may directly insert into amyloidogenic core of aggregates and disrupt pi-pi stacking interactions and thus inhibit amyloid fibril formation. These results may ultimately find applications in the development of potential inhibitors against amyloid fibril formation and its biologically adverse effects.
Paria Akbary; Saeide Biabani; Khaled Soleimani Far
Abstract
Abstract Different fish species tolerate starvation periods using distinct strategies of activating adaptive biochemical and physiological mechanisms that enable them to cope with the adverse condition. The present study was investigated the effect of starvation on growth, chemical compositions and non- ...
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Abstract Different fish species tolerate starvation periods using distinct strategies of activating adaptive biochemical and physiological mechanisms that enable them to cope with the adverse condition. The present study was investigated the effect of starvation on growth, chemical compositions and non- specific immune parameters in grunters (Terapon jarbua) fry. In this study, 180 fry of T.jarbua studied with mean length 4.46± 0.21 cm and weight 1.98± 0.30 g that included fed and starved groups each with three replicates (30 fish per replicate) in a 60 – liter plastic tanks. Sampling of fish was performed at 10, 20 and 30 days of food deprivation. The results showed that specific growth ratio (SGR) and increased weight gain (growth parameters), protein and fat (chemical compositions) levels were significantly lower in starved group than in fed group (P
Fisheries
Bita Seraj; Mesbah Mehrzad; Paria Akbari
Abstract
In this study, in addition to the LC50 and the maximum allowable concentration, effects of silver nanoparticles on several of immune and blood serum enzymes parameters of Barbus grypus were determined For this purpose, 240 shirbut, to investigate the effects of sub lethal toxicity were divided as follows-control ...
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In this study, in addition to the LC50 and the maximum allowable concentration, effects of silver nanoparticles on several of immune and blood serum enzymes parameters of Barbus grypus were determined For this purpose, 240 shirbut, to investigate the effects of sub lethal toxicity were divided as follows-control treatment (G1), the concentration LC50 1% (0.012 mg/L AgNP) (G2), concentration LC50 2% (0.025 mg/L AgNP) (G3) and concentration LC50 4% (0.05 MG/L AgNP) (G4) and concentration LC50 8% (0.1 Mg/ L AgNP) (G5). Then on days zero, 7, 14 and 21 immune responses and serum enzymes (ALT, LDH, SGOP, SGPT) in Barbus grypus were measured. In the study, WBC counts increased significantly (P<0.05) in G2, G3, G4 and G5 treatments compared to control (G1). Serum anti-bacterial activity was enhanced in G3 in twenty first day and G4 and G5 in 14th and 21s days in compared to control. Serum lysozyme activity enhanced significantly (P<0.05) in (G4) in 14th and (G5) 14th and 21s in days compared to control. ALT and LDH Level decreased significantly in (G2), (G3), (G4) and (G5) treatments in 21s day compared to control. SGPT level decreased significantly in (G2), (G3), (G4) and (G5) in 21s day compared to control. SGOT level decreased significantly in (G3), (G4) and (G5) treatments in 21s day compared to control. According to the results of this study concentrations toxicity of nano silver increased immune responses and serum enzymes.
Lida Momeni; Sadegh Farhadian; Behzad Shareghi
Volume 4, Issue 4 , May 2016, , Pages 1-9
Abstract
Abstract Adsorption of proteins on inorganic surfaces may lead to structural and functional changes that are dependent on both the nature of the adsorbed proteins and the physicochemical properties of the inorganic surfaces. Chicken egg white lysozyme (E.C 3.2.1.17, MW=14.6 kDa) is a small globular protein, ...
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Abstract Adsorption of proteins on inorganic surfaces may lead to structural and functional changes that are dependent on both the nature of the adsorbed proteins and the physicochemical properties of the inorganic surfaces. Chicken egg white lysozyme (E.C 3.2.1.17, MW=14.6 kDa) is a small globular protein, that consists of 129 amino acid residues with four disulfide bonds. The aim of this study was the survey of the stability and structure of Chicken egg white lysozyme against ZnO nano through thermal stability, fluorescence and spectroscopy and enzyme activity assay in the absence or presence of ZnO nano particle at pH 7.0. The obtained results indicated that thermal stability and activity of lysozyme decreased with increase in ZnO nanoparticles concentration. Moreover, it was observed that ZnO Nano particle quenched the intrinsic fluorescence of lysozyme. The interaction studies of ZnO nanoparticles and lysozyme show that not only water and solvent molecules can effect on 3D structure of lysozyme and protein but also play an important role in adsorption nanoparticles.
