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Frontiers in Biology

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, Volume 12 Issue 5 Previous Issue   
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REVIEW
Epigenetic regulators sculpt the plastic brain
Ji-Song Guan, Hong Xie, San-Xiong Liu
Front. Biol.. 2017, 12 (5): 317-332.   DOI: 10.1007/s11515-017-1465-z
Abstract   HTML   PDF (559KB)

BACKGROUND: Epigenetic regulation is a level of transcriptional regulation that occurs in addition to the genetic programming found in biological systems. In the brain, the epigenetic machinery gives the system an opportunity to adapt to a given environment to help not only the individual but also the species survive and expand. However, such a regulatory system has risks, as mutations resulting from epigenetic regulation can cause severe neurological or psychiatric disorders.

OBJECTIVE: Here, we review the most recent findings regarding the epigenetic mechanisms that control the activity-dependent gene transcription leading to synaptic plasticity and brain function and the defects in these mechanisms that lead to neurological disorders.

METHODS: A search was carried out systematically, searching all relevant publications up to June 2017, using the PubMed search engine. The following keywords were used: “activity induced epigenetic,” “gene transcription,” and “neurological disorders.”

RESULTS: A wide range of studies focused on the roles of epigenetics in transgenerational inheritance, neural differentiation, neural circuit assembly and brain diseases. Thirty-one articles focused specifically on activity-induced epigenetic modifications that regulated gene transcription and memory formation and consolidation.

CONCLUSION: Activity-dependent epigenetic mechanisms of gene expression regulation contribute to basic neuronal physiology, and defects were associated with an elevated risk for brain disorders.

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Production, purification, characterization, immobilization, and application of Serrapeptase: a review
Selvarajan Ethiraj, Shreya Gopinath
Front. Biol.. 2017, 12 (5): 333-348.   DOI: 10.1007/s11515-017-1461-3
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BACKGROUND: Serrapeptase is a proteolytic enzyme with many favorable biological properties like anti-inflammatory, analgesic, anti-bacterial, fibrinolytic properties and hence, is widely used in clinical practice for the treatment of many diseases. Although Serrapeptase is widely used, there are very few published papers and the information available about the enzyme is very meagre. Hence this review article compiles all the information about this important enzyme Serrapeptase.

METHODS: A literature search against various databases and search engines like PubMed, SpringerLink, Scopus etc. was performed.

RESULTS: We gathered and highlight all the published information regarding the molecular aspects, properties, sources, production, purification, detection, optimizing yield, immobilization, clinical studies, pharmacology, interaction studies, formulation, dosage and safety of the enzyme Serrapeptase.

CONCLUSION:Serrapeptase is used in many clinical studies against various diseases for its anti-inflammatory, fibrinolytic and analgesic effects. There is insufficient data regarding the safety of the enzyme as a health supplement. Data about the anti-atherosclerotic activity, safety, tolerability, efficacy and mechanism of action of the Serrapeptase are still required.

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The value of using polymorphisms in anti-platelet therapy
Habib Haybar, Zeinab Deris Zayeri
Front. Biol.. 2017, 12 (5): 349-356.   DOI: 10.1007/s11515-017-1456-0
Abstract   HTML   PDF (408KB)

OBJECTIVES and BACKGROUNDS: Cardiovascular events occure as a result of various risk factors, such as uric acid (UA), inflammation, hormones and other materials that induce C- reactive protein (CRP) expression. These factors lead to complement activation, and endothelial damages. Damaged endothelial cells release heparan sulfate which inhibits tissue factor activity and von Willed brand factor (VWVF) and causes aggregation. Finally this cascade of events cause platelets aggregation and leads to heart ischemia and cardiovascular events.

DISCUSSION:Anti-platelet therapy is an interesting premise. Anti-platelet resistance patients and bleeding as a result of using ticagrelor and prasugrel should be considered in this treatment methods. Anti-platelet drugs such as clopidogrel are prescribed in cardiovascular events. Platelets have VWF receptors and P2Y12 receptors on their surface, and thus, targeting these receptors can be useful in treatment. The active metabolites of clopidogrel bind to P2Y12R and inhibit ADP binding; thus, clopidogrel inhibits aggregation by interfering in several events as a result of the inhibition of ADP attachment to P2Y12R of the platelet. However, the polymorphisms of P2Y12 and other genes mentioned in Table 1 showed treatment resistance in anti-platelet therapy, highlighting that these SNPs can be helpful in anti-platelet therapy.

CONCLUSION: The knowledge of these SNPs may decrease the number of unwanted effects that endanger patients with cardiovascular diseases and avoids ineffective anti-platelet therapy in several patients. Clopidogrel, ticagrelor, prasugrel, and aspirin and CYP2C19 and their SNPs are very important subjects in anti-platelet therapy. To present the importance of using pharmacogenetics in anti-platelet therapy, we discuss here the association between these drugs and the SNPs for therapeutic resistance.

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RESEARCH ARTICLE
Analysis of p53 expression in partial hydatidiform mole and hydropic abortion
Parvin Kheradmand, Maede Goudarzi, Mina Tavakoli
Front. Biol.. 2017, 12 (5): 357-360.   DOI: 10.1007/s11515-017-1462-2
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BACKGROUND: Gestational trophoblastic disease (GTD) is a heterogeneous group of disorders characterized by abnormal trophoblast tissue. Molar and non-molar hydropic placental changes are the most common forms of GTD. Differential diagnosis of GTD is sometimes problematic. Recently, p53 expression was identified as a good marker for distinguishing GTD types.

AIMS:Comparison of p53 expression in partial hydatidiform mole (PHM) and hydropic abortion.

METHODS: In this prospective cross-sectional study, molar and non-molar hydropic pregnancy specimens were collected. Immunohistochemical staining, based on the Labeled Streptavidin Biotin (LSAB) technique, was carried out on multiple 4mm paraffin block sections prepared from formalin-fixed trophoblastic tissues. Polymer-based Envision was used to assess p53 tumor suppressor protein immunoreactivity. p53 expression was then compared between both groups.

RESULTS: In the study, 40 patients were included: 20 with confirmed PHM and 20 with hydropic pregnancy. p53 protein was positive in 60% of patients with PHM and 25% of patients with hydropic pregnancy. The p53 positive rate was significantly higher in patients with PHM (p = 0.027). Moreover, patients with PHM had a significantly high grade of staining (p<0.001).

CONCLUSION: Our findings indicate that immunohistochemical analysis of p53 protein can be used to distinguish PHM and hydropic pregnancy.

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Evaluation of miR-21 and miR-150 expression in immune thrombocytopenic purpura pathogenesis: a case-control study
Elahe Khodadi, Ali Amin Asnafi, Javad Mohammadi-Asl, Seyed Ahmad Hosseini, Amal Saki Malehi, Najmaldin Saki
Front. Biol.. 2017, 12 (5): 361-369.   DOI: 10.1007/s11515-017-1466-y
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BACKGROUND: Immune thrombocytopenic purpura (ITP) is a common autoimmune disorder diagnosed with thrombocytopenia and bleeding symptoms due to production of autoantibodies (Abs) against platelets. Nowadays, microRNAs are known as novel biomarkers for diagnosis of diseases. The aim of this study was to investigate the expression levels of miR-21 and miR-150 in ITP patients and determine the role of these miRNAs in ITP pathogenesis.

MATERIALS and METHODS:Thirty newly diagnosed patients with acute ITP and 30 healthy subjects( age and sex matched) as controls were enrolled in this study. The expression level of miR-21 and miR-150 was investigated using Real-time-PCR. Comparison of demographic characteristics of the cases was done using independentt-test and chi-square test. Comparison of the expression level of miR-21 and miR-150 with the related parameters was done using independentt-test or Mann–Whitney and Kruskal–Wallis test. Spearman rho correlation coefficient was used to investigate the relationship between the expression of miR-21 and miR-150 with demographic characteristics.

RESULTS: The expression of miR-21, 150 in the patients was not different compared with the control group in general. A significant relationship between the expression of miR-21 with hemoglobin, hematocrit and red blood cell hemoglobin concentration was observed.

DISCUSSION: Expression of miR-21 and miR-150 is not associated with pathogenesis of acute ITP and can involve the synergistic role of other miRNAs. Investigation of miR-21 and miR-150 expression along with other miRNAs and cytokines can be helpful in diagnosis and pathogenesis of ITP.

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Inhibitory effects of YCW and MOS from Saccharomyces cerevisiae on Escherichia coli and Salmonella pullorum adhesion to Caco-2 cells
Xiaoqing Xu, Yu Qiao, Qing Peng, Long Gao, Bo Shi
Front. Biol.. 2017, 12 (5): 370-375.   DOI: 10.1007/s11515-017-1464-0
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BACKGROUND: For many years, yeast cell walls (YCW) and mannan oligosaccharides (MOS) have been used as alternatives to antibiotics and health feed additives to enhance the growth performance and health of food animals. In the present study, the inhibitory effects of YCW and MOS on the adhesion of enteropathogenic bacteria to intestinal epithelial cells were tested.

METHODS: YCW and MOS were extracted from Saccharomyces cerevisiae (XM 0315), and the morphology of YCW and MOS bound to pathogenic bacteria was observed by scanning electron microscopy (SEM). Real-time fluorescent quantitative PCR was used to quantitatively analyze the effects of YCW and MOS on the adhesion ofEscherichia coli (CVCC3367) and Salmonella pullorum (CVCC520) to Caco-2 cells.

RESULTS: The results showed that YCW inhibited E. coli and S. pullorum binding to Caco-2 cells by 95% and 74%, respectively, whereas MOS prevented E. coli and S. pullorum binding by 67% and 50%, respectively.

CONCLUSIONS: These data suggest that YCW has a stronger ability than MOS to inhibit pathogenic bacteria from adhering to Caco-2 cellsin vitro.

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Strain improvement, optimization and purification studies for enhanced production of streptokinase from Streptococcus uberis TNA-M1
Teetam Ghosal, Nikita Augustine, Ashwini Siddapur, Vaishnavi Babu, Merlyn Keziah Samuel, Subathra Devi Chandrasekaran
Front. Biol.. 2017, 12 (5): 376-384.   DOI: 10.1007/s11515-017-1467-x
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BACKGROUND: Screening of isolates for their potency to produce streptokinase was an important criterion of this research. The current study emphasizes the strain improvement, optimization and purification studies for enhanced production of streptokinase fromStreptococcus uberisTNA-M1 isolated from bovine milk.

METHODS: The study was carried out on samples collected from milk sample. Primary screening and characterization is used as an excellent source for the isolation of β-hemolytic organisms. Strain improvement was done by both physical & chemical mutagenesis. The enzyme activity was checked by clot lysis assay and confirmed by fibrin plate method. The partially purified and crude enzyme were analysed by high-performance liquid chromatography. Molecular weight & enzyme purity was checked by SDS –PAGE, further confirmed by fibrin zymography.

RESULTS: Out of the 3 isolated strains, only one isolate expressed β-haemolysis with streptokinase (SK) activity. Based on the results of radial caseinolytic assay and blood clot dissolving assay, isolate TNA-M1 demonstrated the highest streptokinase activity. Based on morphological , biochemical and molecular characterization, it was identified asStreptococcus uberis and the strain was named as Streptococcus uberis TNA-M1. The results indicated that ultra-violet (UV) and ethyl methane sulfonate (EMS) were effective mutagenic agents for strain improvement ofStreptococcus uberis TNA-M1 and enhanced SK productivity. HPLC analysis was performed in order to confirm the presence of streptokinase with the similar retention time (0.875 min) with its standard (0.854) min. SDS-PAGE of the enzyme showed protein band of approximately 47 kDa and confirmed by fibrin zymography. It exhibited fibrinolytic activity, which was more potent than other fibrinolytic enzymes. Glucose and peptone were recorded to be the optimum carbon and nitrogen sources respectively.

CONCLUSION: Thus this study presents its novelty by highlighting the potential ofStreptococcus uberisTNA-M1 as a significant source for the production of fibrinolytic enzymes.

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