Inhibitory Role of β-Casein on the α-Synuclein Aggregation Associated with Parkinson’s Disease In Vitro

Large soluble oligomeric species are observed as probable intermediates during fibril formation in aggregations of Parkinson’s disease (PD). Fibrillar deposits occur in PD. Amyloid forms α-Synuclein is one of the main compounds aggregations. β-Casein, a member of the Casein family, has been demonstrated to inhibit α-Synuclein aggregation by chaperone-like activity. In this study, we investigated the effect of chaperone activity of β-Casein in preventing the aggregation of α-Synuclein protein. We have examined the effect of β-Casein in preventing α-Synuclein aggregation by using from Thioflavin T-binding assay, transmission electron microscopy, ANS-binding assay, circular dichroism spectroscopy and FTIR spectroscopy. Results from the ThT binding assay demonstrated an increase in the ThT fluorescence intensity of α-Synuclein incubated in absence of β-Casein but in its presence fluorescence intensity is decreased. Electron microscopy data also indicated that β-Casein decreased the aggregation content of α-Synuclein. ANS results also showed that β-Casein significantly decreased the the hydrophobic area in α-Synuclein incubated. Circular dichroism spectroscopy (CD) results also showed that β-sheet structures of α-Synuclein incubated change to structural α-helical and β-turn in presence of β-Casein. FTIR spectroscopy indicates the presence of β-sheet structures in α-Synuclein incubated in absence of β-Casein and β-sheet structures decreased in its presence. Thus, our results suggest that in vitro, β-Casein interacts with α-Synuclein fibrils, changes the α-Synuclein structure and prevents amyloid fibril formation. This means that β-Casein could be essential for therapies inhibiting aggregation and to be an important therapeutic drug against PD.     

Effect of long-term exposure to mobile phone radiation on alpha-Int1 gene sequence of Candida albicans

Over the last decade, communication industries have witnessed a tremendous expansion, while, the biological effects of electromagnetic waves have not been fully elucidated. Current study aimed at evaluating the mutagenic effect of long-term exposure to 900-MHz radiation on alpha-Int1 gene sequences of Candida albicans. A standard 900 MHz radiation generator was used for radiation. 10 ml volumes from a stock suspension of C. albicans were transferred into 10 polystyrene tubes. Five tubes were exposed at 4 °C to a fixed magnitude of radiation with different time periods of 10, 70, 210, 350 and 490 h. The other 5 tubes were kept far enough from radiation. The samples underwent genomic DNA extraction. PCR amplification of alpha-Int1 gene sequence was done using one set of primers. PCR products were resolved using agarose gel electrophoresis and the nucleotide sequences were determined. All samples showed a clear electrophoretic band around 441 bp and further sequencing revealed the amplified DNA segments are related to alpha-Int1 gene of the yeast. No mutations in the gene were seen in radiation exposed samples. Long-term exposure of the yeast to mobile phone radiation under the above mentioned conditions had no mutagenic effect on alpha-Int1 gene sequence.     

Genetics and rheumatoid arthritis susceptibility in Iran

Rheumatoid arthritis (RA) is an autoimmune disorder with a number of risk factors, including both genetic and environmental. A number of RA risk associated genomic loci has been identified. In this review, we summarize the association of genetic factors with RA reported in population studies in Iran. No significant association was found between the majority of genetic factors identified in other populations and risk for RA in the Iranian subjects. This conflicting result could be due to the ethnic differences and diversity that are present in Iran. We conclude that there is a need to investigate larger groups of Iranian subjects, encompassing different regions of Iran, to either prove or refute these initial findings.     

In Silico Design of Multimeric HN-F Antigen as a Highly Immunogenic Peptide Vaccine Against Newcastle Disease Virus

Application of molecular biology techniques to the production of new vaccines against different strains of the Newcastle disease virus (NDV) has been the subject of recent research reports. Development of improved techniques for genome sequencing has led to the recognition of protective mechanisms and the identification of possible candidate antigens. Such procedures could generate meaningful results regarding the virulence determinants of NDV. This study proposed an in silico approach by assembling potential and conserved epitopic regions of hemagglutinin–neuraminidase (HN) and fusion (F) glycoproteins of NDV to induce multiepitopic responses against the virus. Epitope predictions showed that the hypothetical synthetic construct could induce immature B and T cell epitopes that expect a high immune response because of their location in four distinct parts of the construct, namely the head, stalk and the heptad repeated regions known as the HRA and HRB domains. Most regions of the chimeric construct were found to have high antigenic propensity and surface accessibility, which further confirmed the strategy for selection of precise continuous and discontinuous epitopes of HN and F antigens. Thermodynamic folding of mRNA structures revealed correct folding of the RNA construct, indicating good stability of the mRNA to increase the efficiency of translation in the target host. The three-dimensional structure of the native HN-F chimeric protein was successfully generated and validated as a proper model which may define reliability, structural quality and conformation.     

Pyrolysis of Mixed Date Stones and Pistachio Shells: Identification of Bio-Oil and Utilization of Bio-Char as Activated Carbon Precursor

Thermal pyrolysis of mixed date stones and pistachio shells in a semi-batch reactor was addressed in this study. The highest yield of liquids (51.20 %) was produced at 500 °C, 90 min, 20 °C/min heating rate, and 50 mesh particle size. Under these conditions, yield of liquid from date stones and pistachio shells separately was 49.12 % and 47.67 %, respectively. The FT-IR results confirmed the presence of multiple oxygen-containing compounds in the bio-oil. Results from GC–MS declared that it was predominately composed of acids (57.57 %), esters (21.35 %), phenols (4.63 5), and alcohols (3.49 5). The obtained biochar was transformed into activated carbon (AC) by the optimized ZnCl₂ activation method. The ideal AC was synthesized at 600 °C for 60 min using a 2 : 1 ZnCl₂: biochar impregnation ratio. FESEM and XRD measurements showed that the AC was amorphous. The prepared AC was effective in eliminating dibenzothiophene (DBT) from model fuel (200 ppm DBT/hexane) with a maximum performance 95.26 % at 40 °C for 1h using 0.35 g of the AC. The exhausted AC was regenerated and reutilized 4 times, and removal efficiency reached 88.23 % in the 4^th cycle under ideal working conditions.     

Effect of mesenchymal stem cells-derived exosomes on tumor microenvironment: Tumor progression versus tumor suppression

Mesenchymal stem cells (MSCs) are multipotent cells with the potential to differentiate into different cell types. Owing to their immunosuppressive and anti-inflammatory properties, they are widely used in regenerative medicine, but they have a dual effect on cancer progression and exert both growth-stimulatory or -inhibitory effects on different cancer types. It has been proposed that these controversial effects of MSC in tumor microenvironment (TME) are mediated by their polarization to proinflammatory or anti-inflammatory phenotype. In addition, they can polarize the immune system cells that in turn influence tumor progression. One of the mechanisms involved in the TME communications is extracellular vesicles (EVs). MSCs, as one of cell populations in TME, produce a large amount of EVs that can influence tumor development. Similar to MSC, MSC-EVs can exert both anti- or protumorigenic effects. In the current study, we will investigate the current knowledge related to MSC role in cancer progression with a focus on the MSC-EV content in limiting tumor growth, angiogenesis, and metastasis. We suppose MSC-EVs can be used as safe vehicles for delivering antitumor agents to TME.     

Comparison of the properties of rare variants of alpha1-proteinase inhibitor expressed in COS-1 cells and assessment of their potential as risk factors in human disease

Among the more than 75 known variants of alpha(1)-proteinase inhibitor, a sub-population of rare, point mutations causing single amino acid replacements have been identified and classified as "at risk" alleles for development of pulmonary disease. In most cases, it is not clear how the amino acid replacements typical of these variants change the properties of the inhibitor to increase risk of disease in the affected individuals. To begin to address this question, we mutagenized a wild type alpha(1)-proteinase inhibitor cDNA to encode a panel of eight different point mutants reported to be associated with increased risk for development of pulmonary disease. These variants were then expressed in COS-l cells transiently transfected with plasmids containing the altered cDNAs. The effects of the mutations on the rates of secretion, cellular location, intracellular degradation, activity, stability, and tendency to aggregate were determined. Results of these studies show that, in some cases, the mutations affect the rate of secretion, the activity or both of these properties of alpha(1)-proteinase inhibitor in a manner consistent with its designation as an "at-risk" allele. In other cases, the mutations do not significantly change the properties of the inhibitor, suggesting that these may be normal variants and that their expression may not increase the risk of disease.     

Genetic diversity of Iranian clinical isolates of Mycobacterium tuberculosis

In the current study we aimed to execute a rather less complicated molecular tying method, i.e. the random amplification of polymorphic DNA (RAPD) analysis to find the heterogeneity of Iranian strains of Mycobacterium tuberculosis. The isolates comprised a total of 96 strains of M. tuberculosis collected from clinical specimens of patients in Isfahan and Tehran. The isolates were assigned to the species M. tuberculosis by the key conventional and molecular methods. They were then subjected to RAPD analysis by four arbitrary primers, namely, the primers 27F, 1525R, MS- GF and INS-2. They were then evaluated for the number and intensity of the band patterns. The RAPD profiles of the Iranian isolates showed a degree of heterogeneity which varied based on the primer used. However, analysis of the isolates by primer INS-2 revealed the highest degree of diversity yielding 31 distinguishable RAPD types. RAPD analysis provides a rapid and easy means of identifying heterogeneity among the M. tuberculosis isolates. This typing system might be considered a valuable alternative molecular typing for countries with limited resources provided that the reproducibility and reliability of the method is carefully assured.     

The effect of Candida cell wall beta-glucan on treatment-resistant LL/2 cancer cell line: in vitro evaluation

Candida albicans (C. albicans) cell wall beta-glucan has been considered as a potential agent in the treatment of cancers due to its anti-tumor properties. Therefore, in the present study, we investigated the anti-cancer effects of Candida cell wall beta-glucan on Lewis lung carcinoma cell line (LL/2) cells. Beta-glucan of C. albicans cell wall was extracted. LL/2 cell line was cultured, then sphere cells and parental cells were exposed to the different concentrations of beta-glucan extracted from C. albicans (10–6000 μg/ml), for 24, 48 and 72 h. Cytotoxicity of beta-glucan was assayed by MTT test, then RNA extracted from cells population (treated and untreated cells), cDNA synthetized and expression level of Sox2, Oct4, C-myc, Nanog genes were also investigated using Real-time methods. At optimal concentrations of 800 and 1000 μg/ml, the extracted beta-glucan showed a significant cytotoxic effect on both parental and sphere cell populations (p?<?0.05). Real-time PCR analysis revealed a decreased expression of Oct4 and Sox2 genes in treatment of cells with beta-glucan compared with control group. Since the extracted beta-glucan showed an inhibitory effect on the expression of Oct4 and Sox2 genes involved in LL/2 metastasis, therefore, beta-glucan can be considered as an anti-tumor agent because of its anti-metastatic properties, however, more in vitro and in vivo studies are needed to provide further evidence on this topic in the future.

     

The stability evaluation of mesenchymal stem cells differentiation toward endothelial cells by chemical and mechanical stimulation

Adipose-derived mesenchymal stem cells (ADSCs) are adult multipotent cells able to differentiate into several cell lineages. Vascular endothelial growth factor (VEGF) and the shear stress associated with blood flow are considered as the most important chemical and mechanical cues that play major roles in endothelial differentiation. However, the stability of endothelial-specific gene expression has not been completely addressed yet. ADSCs in passage 3 were cultured inside the tubular silicon tubes and then exposed to VEGF or shear stress produced in a perfusion bioreactor. To investigate the differentiation, the expression levels of Flk-1, von Willebrand factor (vWF), and vascular endothelial-cadherin (VE-cadherin) were studied using Real-Time PCR. For studying the endothelial differentiation stability, mRNA levels of the genes were evaluated in certain time intervals after completion of the tests so as to determine whether the expression level of each gene in different time points was stable and remained constant or not. Application of VEGF and shear stress caused an elevation in endothelial cells’ specific genes. Although there are some changes following the days after application of mechanical and chemical stimuli, the gene expression results depicted significantly higher gene expression between sequential chemically and mechanically incited groups. In conclusion, stress alone can be a differentiating factor, by itself. Our results verified the efficient stable differentiation ability of the chemical and mechanical factors.