The dual behavior of heat shock protein 70 and asymmetric dimethylarginine in relation to serum CRP levels in type 2 diabetes

Background

Experimental evidence suggests that heat shock proteins (HSP) and asymmetric dimethylarginine (ADMA) are induced in the state of chronic inflammation and stress conditions. They are both inhibitors of nitric oxide synthase (NOS). The aim of this study was to evaluate the correlation between ADMA and HSP70, in patients with type 2 diabetes with respect to serum levels of C reactive protein (CRP).

Methods

We quantified serum HSP70, ADMA and CRP in 80 newly-diagnosed patients with type 2 diabetes plus 80 age-, sex and BMI-matched healthy controls. The patients and controls were also stratified into groups of high and low CRP levels (cut-point: 2.5 mg/ml).

Results

Patients with type 2 diabetes had significantly higher serum HSP70 (0.52 [0.51–0.66] vs. 0.27 [0.26–0.36], p < 0.001), ADMA (0.86 [0.81–0.92] vs. 0.72 [0.71–0.85], p < 0.05) and CRP (2.9 [1.7–3.4] vs. 1.6[1.2–2.3], p < 0.05) compared with healthy controls. Serum HSP70 and ADMA levels were significantly correlated in patients with high CRP levels (r = 0.89, p < 0.01), whereas there were no correlation in patients with low CRP (r = − 0.37, p = 0.07) and controls. This correlation was significant (r = 0.77, p < 0.001) in patients with high CRP and also in patients with low CRP levels (r = − 0.51, p < 0.05), after multiple adjustments for LDL and HDL levels.

Discussion

We showed that, in a state of high inflammation; serum levels of ADMA parallel the HSP70 levels. However in low inflammation, they are negatively correlated. The duality in HSP70 and ADMA correlation may be related to the duality of NOS function in low and high CRP levels.     

Cytokine gene polymorphism and asthma susceptibility, progress and control level

Asthma is a multifactor inflammatory disorder, and its management requires understanding of its various pathogenesis and control mechanisms. Cytokines and other inflammatory mediators are important factors in asthma pathophysiology. In this study, we evaluated the role of cytokine polymorphisms in the asthma susceptibility, progress, control, and lung functions. IL-4-C590T polymorphism by PCR-RFLP method, IFN-γ T+874A, TNF-α-A308G, IL-6 G−174C and TGF-β T+869C variants by ARMS-PCR method and IgE serum level by ELISA technique were determined in 81 asthmatic patients and 124 normal subjects. Asthma diagnosis, treatment and control levels were considered using standard schemes and criteria. TNF-α−308GA genotype was more frequent in asthmatics (P = 0.025, OR 3.352), and polymorphisms between different asthma control levels (P > 0.05) were not different. IFN-γ+874AT genotype had a positive correlation with the familial history of asthma (P = 0.034, OR 2.688). IL-6−174C allele (P = 0.045), TNF-α−308GG genotype (P = 0.002) and TNF-α−308G allele (P = 0.004) showed reduced values, and TNF-α−308GA genotype (P = 0.002) increased FEF25-75 value in asthmatics. IFN-γ+874AA genotype caused a decrease in FVC factor (P = 0.045). This study showed that TNF-α−308GA is a risk factor for asthma, but cytokine gene variants do not affect asthma control and IgE serum levels. Variants producing lower levels of IL-6, TNF-α and IFN-γ are associated with reduced pulmonary capacities. To achieve an appropriate schema for asthma management, further studies with consideration of different aspects in a larger group of patients would be more elucidative.     

Synthesis and characterization of pyruvate-isoniazid analogs and their copper complexes as potential ICL inhibitors

Currently used anti-tubercular drugs target actively growing Mycobacterium tuberculosis (Mtb) but there are no current therapies targeting persistent mycobacteria. Isocitrate lyase (ICL) is an important enzyme of the glyoxylate shunt pathway used by Mtb for sustaining intracellular infection in inflammatory macrophages under conditions of stress such as nutrient depletion and anaerobic metabolism. Since the humans do not possess this enzyme it constitutes an attractive target for selective drug design. Present work describes synthesis and structural characterization of pyruvate-isoniazid conjugates and their copper complexes with potent anti-tubercular activities against M. tuberculosis H37Rv.     

Disruption of tubulin polymerization and cell proliferation by 1-naphthylarsonic acid

Arsenical compounds exhibit a differential toxicity to cancer cells. Microtubules are a primary target of a number of anticancer drugs, such as arsenical compounds. The interaction of 1-NAA (1-naphthylarsonic acid) has been investigated on microtubule polymerization under in vitro and cellular conditions. Microtubules were extracted from sheep brain. Transmission electron microscopy was used to show microtubule structure in the presence of 1-NAA. Computational docking method was applied for the discovery of ligand-binding sites on the microtubular proteins. Proliferation of HeLa cells and HF2 (human foreskin fibroblasts) was measured by the MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide] assay method following their incubation with 1-NAA. Fluorescence microscopic labelling was done with the help of α-tubulin monoclonal antibody and Tunel kit was used to investigate the apoptotic effects of 1-NAA on the HeLa cells. 1-NAA inhibits the tubulin polymerization by the formation of abnormal polymers having high affinity to the inner cell wall.     

Immunization with M2e-Displaying T7 Bacteriophage Nanoparticles Protects against Influenza A Virus Challenge

Considering the emergence of highly pathogenic influenza viruses and threat of worldwide pandemics, there is an urgent need to develop broadly-protective influenza vaccines. In this study, we demonstrate the potential of T7 bacteriophage-based nanoparticles with genetically fused ectodomain of influenza A virus M2 protein (T7-M2e) as a candidate universal flu vaccine. Immunization of mice with non-adjuvanted T7-M2e elicited M2e-specific serum antibody responses that were similar in magnitude to those elicited by M2e peptide administered in Freund’s adjuvant. Comparable IgG responses directed against T7 phage capsomers were induced following vaccination with wild type T7 or T7-M2e. T7-M2e immunization induced balanced amounts of IgG₁ and IgG_2a antibodies and these antibodies specifically recognized native M2 on the surface of influenza A virus-infected mammalian cells. The frequency of IFN-γ-secreting T cells induced by T7-M2e nanoparticles was comparable to those elicited by M2e peptide emulsified in Freund’s adjuvant. Emulsification of T7-M2e nanoparticles in Freund’s adjuvant, however, induced a significantly stronger T cell response. Furthermore, T7-M2e-immunized mice were protected against lethal challenge with an H1N1 or an H3N2 virus, implying the induction of hetero-subtypic immunity in our mouse model. T7-M2e-immunized mice displayed considerable weight loss and had significantly reduced viral load in their lungs compared to controls. We conclude that display of M2e on the surface of T7 phage nanoparticles offers an efficient and economical opportunity to induce cross-protective M2e-based immunity against influenza A.     

Comparative modeling of DszC, an enzyme in biodesulfurization, and performing in silico point mutation for increasing tendency to oil

Desulfurization protein named DszC from Rhodococcus erythropolis is the key enzyme for biodesulforization of dibenzothiophene (DBT) in 4S pathway, which is a pathway with four enzymes. DszC enzyme biodesulfurizes DBT and its derivatives in oil components and biphasic systems. It functions well at the oil- water interface. In this study point mutation performed in DszC enzyme regarding to increase protein hydrophobicity and stability for application in immobilized form. 3D model of DszC predicted using Phyre2, SAM-T08 and M4t servers. I-Mutant 2 server used to determine potential spots for point mutation, and Molegro Virtual Docker (MVD) used for performing point mutation on 3D model. Hydrophobicity plots generated by Bioedit version 7.0.8.0 in Kyte-Doolittle scale indicated that protein hydrophobicity is increased after mutation. Also protein stability increased 26.11 units in scale of DDC2.     

Homology modeling and molecular dynamics simulation of odonthubuthus doriae (Od1) scorpion toxin in comparison to the BmK M1

All of the α-subgroups share similarity in their sequence and structure but different in the toxicity to various voltage-gated sodium channels (VGSCs). We modeled the first 3D structural model of the Od1 based on BmK M1 using homology modeling. The reliability of model for more investigation and compare to BmK M1 has been examined and confirmed. Then the model structure is further refined by energy minimization and molecular dynamics methods. The purpose of this modeling and simulation is comparison toxicity of two mentioned toxins by investigation structural feature of functional regions including core domain, 5-turn and C-terminal which make NC domain. In the one hand, it is intriguing that Od1 in comparison to BmK M1 shows same solvent accessible surface area (SASA) in 5-turn region but a little more exposed and feasibility (more SASA) in C-terminal region and key functional residues of C-terminal such as positive residues Arg58, lys62 and Arg (His)64. These data suggested that Od1 has similarity with BmK M1 but has more toxicity to sodium channel. In the other hand 5-turn proximity of C-terminal to 5-turn in BmK M1with cis peptide bond is less than Od1 without cis peptide bond which is a confirmation with experimental data about BmK M1.A better understanding of the 3-D structure of Od1and comparison to BmK M1 will be helpful for more investigation of functional characters action of natural toxins with a specialized role for VGSCs.     

Prediction of membrane protein types by means of wavelet analysis and cascaded neural networks

In this study, membrane proteins were classified using the information hidden in their sequences. It was achieved by applying the wavelet analysis to the sequences and consequently extracting several features, each of them revealing a proportion of the information content present in the sequence. The resultant features were made normalized and subsequently fed into a cascaded model developed in order to reduce the effect of the existing bias in the dataset, rising from the difference in size of the membrane protein classes. The results indicate an improvement in prediction accuracy of the model in comparison with similar works. The application of the presented model can be extended to other fields of structural biology due to its efficiency, simplicity and flexibility.     

Molecular phylogenetic study of the Iranians based on polymorphic markers

The application of polymorphic markers in construction of phylogenetic trees has been documented. Five polymorphic markers located in the PAH gene region including PAH-BglII, PAH-PvuII(A), PAH-EcoRI, PAH-MspI and PAH-STR were selected for analysis of phylogenetic relationships of the Iranians with 15 other populations of the world. The lowest genetic distance was observed between the Iranians and populations residing in Adygei (an ethnic group of the Russian Caucasus), Russia and Druze (a Middle Eastern group). However, East Asian populations including Han, Japanese and Cambodians, Khmer or the Oceanians (Melanesian, Nasioi) showed high genetic distance with the Iranians. The data suggested that the Iranians might have relatively close evolutionary history with the populations residing in Russia rather than East Asian populations. This study provided the first new molecular insight into the evolutionary history of the Iranian population.