The protective role of Coenzyme Q10 in metallothionein-3 expression in liver and kidney upon rats’ exposure to lead acetate

Molecular Biology Reports - Metallothionein-3 (MT3) is an antioxidant protein that alters after exposure to heavy metals. In this study, we investigated the hepatic and renal expression of MT3 gene...     

Study of resistance components of some promising wheat lines to yellow rust disease in the seedling stage

The most reliable method to control the wheat yellow rust disease is cultivation of resistance cultivars. To provide resistance, it is necessary to be aware of the amount and the quality of pathogenesis of disease factors and resistant specifications. In this study, 82 wheat promising lines with Bolani susceptible cultivar in randomised complete block design were tested in the seedling stage. This experiment was carried out in greenhouse condition, and it was assessed by two races: 166E254A+Yr27+ and 6E150A+, which were more and less pathogenic, respectively. The attributes of resistance were measured for infection type (IT), latent period (LP), pustule size (PS) and density. Results of variance analysis relating two races between wheat genotypes for these four attributes of resistance showed that there is a difference in the probability at 1% level. The statistical analyses for these components of resistance indicated that there is negative and high solidarity between IT and LP, and also among the number and density of pustules. The correlation between IT and LP and both races were -0.90 and -0.98, respectively. Cluster analysis of lines to each race was classified as resistant, semi-resistant and susceptible. The first group of the resistant lines were 27 lines in which their ITs of 0–2, mean LP of 18?days PS of 2.8 and pustule density of 1.1 were recorded.     

Evaluation of expression CXCL8 chemokine and its relationship with oocyte maturation and embryo quality in the intracytoplasmic sperm injection method

Molecular Biology Reports - The present study aimed to evaluate the expression of the chemokine CXCL8 in both mRNA and protein levels in the serum, follicular fluid (FF), and cumulus cells (CCs)...     

Protein refolding assisted by molecular tube based α-cyclodextrin as an artificial chaperone

In this study, we evaluated, for the first time, the application of molecular tube based alpha-cyclodextrin for improving the refolding yields of two different enzymes: carbonic anhydrase and alkaline phosphatase. Our results indicate that under the optimal developed refolding environments, the denatured carbonic anhydrase and alkaline phosphatase were refolded with a yield of 51 and 61% using 15 and 5 mg/ml of the molecular tube, respectively. Regardless of lower refolding yields compared with liquid-phase artificial chaperone assisted approach, the new technique (solid-phase artificial chaperone assisted refolding) benefits from easier and faster separation of the refolded product from the refolding environment, recycling of the stripping agent, and finally, significantly less environmental effect at the industrial levels. However, further improvements in solid-phase artificial chaperone assisted technique are needed either through synthesizing better stripping agents or by optimizing and defining better refolding environments.     

Spectroscopic characterization of furosemide binding to human carbonic anhydrase II

This study reports the interaction between furosemide and human carbonic anhydrase II (hCA II) using fluorescence, UV-vis and circular dichroism (CD) spectroscopy. Fluorescence data indicated that furosemide quenches the intrinsic fluorescence of the enzyme via a static mechanism and hydrogen bonding and van der Walls interactions play the major role in the drug binding. The binding average distance between furosemide and hCA II was estimated on the basis of the theory of F?rster energy transfer. Decrease of protein surface hydrophobicity was also documented upon furosemide binding. Chemical modification of hCA II using N-bromosuccinimide indicated decrease of the number of accessible tryptophans in the presence of furosemide. CD results suggested the occurance of some alterations in α-helical content as well as tertiary structure of hCA II upon drug binding.     

Appraisal of casein's inhibitory effects on aggregation accompanying carbonic anhydrase refolding and heat-induced ovalbumin fibrillogenesis

It is well accepted that whole casein and its purified major components, due to their chaperone-like activity, are able to suppress the thermal and chemical aggregation of several substrate proteins. In this study, we set out to determine whether whole and β-casein are able to prevent (or attenuate) aggregation accompanying refolding of chemically denatured carbonic anhydrase or to recover lost biological activity after its denaturation. Additionally, we showed attenuated heat-induced fibrillar aggregation of egg white ovalbumin in the presence of these commonly occurring unfolded proteins, as molecular chaperones. Also, the extent, rate and order of aggregation, in the presence and absence of aggregation suppressors, were compared. Although β-casein did not prevent aggregation as strong as whole casein, both chaperones were efficient not only in suppressing the aggregation extent of denatured carbonic anhydrase, but also in delaying elongation process of amyloid fibril formation with no effect on nucleation phase.     

Synthesis, in vitro antibacterial and carbonic anhydrase II inhibitory activities of N-acylsulfonamides using silica sulfuric acid as an efficient catalyst under both solvent-free and heterogeneous conditions

Silica sulfuric acid catalyzes efficiently the reaction of sulfonamides with both carboxylic acid anhydrides and chlorides under solvent-free and heterogeneous conditions. All the reactions were done at room temperature and the N-acylsulfonamides were obtained with high yields and purity via an easy work-up procedure. This method is attractive and is in a close agreement with green chemistry. These compounds were also investigated for antibacterial activity, including Gram-positive cocci and Gram-negative bacilli, and carbonic anhydrase II inhibitory activity.     

Synthesis,Characterization, Molecular Modeling,and DNA Interaction Studies of Copper Complex Containing Food Additive Carmoisine Dye

A copper complex of carmoisine dye; [Cu(carmoisine)₂(H₂O)₂]; was synthesized and characterized by using physico-chemical and spectroscopic methods. The binding of this complex with calf thymus (ct) DNA was investigated by circular dichroism, absorption studies, emission spectroscopy, and viscosity measurements. UV-vis results confirmed that the Cu complex interacted with DNA to form a ground-state complex and the observed binding constant (2× 10⁴ M^?1) is more in keeping with the groove bindings with DNA. Furthermore, the viscosity measurement result showed that the addition of complex causes no significant change on DNA viscosity and it indicated that the intercalation mode is ruled out. The thermodynamic parameters are calculated by van't Hoff equation, which demonstrated that hydrogen bonds and van der Waals interactions played major roles in the reaction. The results of circular dichroism (CD) suggested that the complex can change the conformation of DNA from B-like form toward A-like conformation. The cytotoxicity studies of the carmoisine dye and its copper complex indicated that both of them had anticancer effects on HT-29 (colon cancer) cell line and they may be new candidates for treatment of the colon cancer.     

Heme, as a chaperone, binds to amyloid fibrils and forms peroxidase in vitro: Possible evidence on critical role of non-specific peroxidase activity in neurodegenerative disease onset/progression using the α-crystallin-based experimental system

We report that heme not only displays high binding affinity to the aggregates of crystallin, but also it is effectively able to interfere with this type of aggregation. In the present study, the influence of heme concentration on the crystallin fibrillogenesis was also investigated and experimental evidence of heme’s prevention of crystallin aggregation was provided with the help of spectroscopic measurements. Significantly, using α-crystallin-based experimental system, we proposed that elevated levels of peroxidase activity may have a determinant role in amyloid pathogenesis. The substantial peroxidase activity of “crystallin aggregate-heme” may partially explain the acceleration of oxidative damage in several amyloid-affected neurodegenerative diseases. The present study also suggests that lipid peroxidation accompanying amyloidogenesis may be considered as a major cause in the pathogenesis of amyloid disorders. Since the consequence of heme-amyloid interaction has yet to be identified, additional data on it may help us to manage amyloid aggregation processes.     

Nonlinear modeling of the atrioventricular node physiology in atrial fibrillation

A nonlinear model of the atrioventricular (AV) node physiology in atrial fibrillation (AF) is proposed based on three assumptions: (1) normal distribution of atrial impulses, (2) right-skewed distribution of R-R intervals, (3) increase in the refractory period of the AV node due to rapid bombardment from the atria. Simulation resulted in the following conclusions, all of which are in agreement with previous experience: (1) the entry speed of atrial impulses into the AV node in AF is inversely proportional to the ventricular rate, (2) the autocorrelation function of R-R intervals is zero at all delays, (3) a newly introduced index, sign of first difference, has a negative autocorrelation function at the first delay and zero ones at all others. In spite of its simplicity, the model is able to explain what happens in atrial premature complexes, sinus tachycardia and sinus bradycardia. Different rhythms, some of which rarely seen clinically, can be reproduced by changing input patterns or by slightly manipulating the model parameters. In order to make possible a long irregular time series of R-R interval, aperiodic changes in atrial signals are shown to be necessary. In conclusion, we proposed a simple model for the AV node physiology capable of explaining the previously known facts about AF as well as predicting interesting properties of some other supraventricular arrhythmias.