Synthetic biology in various cellular and molecular fields: applications,limitations, and perspective

Molecular Biology Reports - Synthetic biology breakthroughs have facilitated genetic circuit engineering to program cells through novel biological functions, dynamic gene expressions, as well as...     

Melatonin,a toll-like receptor inhibitor: Current status and future perspectives

Toll-like receptors (TLRs) are crucial activators of inflammatory responses, they are considered immune receptors. TLRs are of fundamental importance in the pathophysiology of disorders related to inflammation including neurodegenerative diseases and cancer. Melatonin is a beneficial agent in the treatment of inflammatory and immune disorders. Melatonin is potent anti-inflammatory hormone that regulates various molecular pathways. Withal, limited studies have evaluated the inhibitory role of melatonin on TLRs. This review summarizes the current knowledge related to the effects of melatonin on TLRs in some common inflammatory and immunity disorders.     

Direct electrical stimulation enhances osteogenesis by inducing Bmp2 and Spp1 expressions from macrophages and preosteoblasts

The capability of electrical stimulation (ES) in promoting bone regeneration has already been addressed in clinical studies. However, its mechanism is still being investigated and discussed. This study aims to investigate the responses of macrophages (J774A.1) and preosteoblasts (MC3T3-E1) to ES and the faradic by-products from ES. It is found that pH of the culture media was not significantly changed, whereas the average hydrogen peroxide concentration was increased by 3.6 and 5.4 µM after 1 and 2 hr of ES, respectively. The upregulation of Bmp2 and Spp1 messenger RNAs was observed after 3 days of stimulation, which is consistent among two cell types. It is also found that Spp1 expression of macrophages was partially enhanced by faradic by-products. Osteogenic differentiation of preosteoblasts was not observed during the early stage of ES as the level of Runx2 expression remains unchanged. However, cell proliferation was impaired by the excessive current density from the electrodes, and also faradic by-products in the case of macrophages. This study shows that macrophages could respond to ES and potentially contribute to the bone formation alongside preosteoblasts. The upregulation of Bmp2 and Spp1 expressions induced by ES could be one of the mechanisms behind the electrically stimulated osteogenesis.     

Gender differences in inflammatory proteins and pathways in seasonal allergic rhinitis

In model organisms, thousands of genes differ in expression between females and males. It is not known if differences on a similar scale are found in humans nor how this relates to disease. However, in allergic disease gender differences in the levels of both inflammatory cells and proteins have been shown. In this study, we found lower nasal fluid allergen-specific IgE in women than men with seasonal allergic rhinitis (SAR). This led to genome-wide analyses of gene expression in allergen-challenged CD4⁺ cells from patients with SAR before and after treatment with cortisone. Before treatment, 975 genes differed in expression between women and men: 337 were higher in women. After treatment only 428 genes and one pathway differed in expression. The genes that differed in expression between women and men were over-represented in 10 pathways. Five of the pathways regulated chemotaxis. All five were less active in women. One of the pathways was induced by the eosinophilic chemokine CCL4. Analysis of nasal fluid CCL4 protein confirmed lower levels in women with seasonal allergic rhinitis, before and during the pollen season. By contrast, nasal fluid CCL3 levels did not differ between the genders. In summary, this study shows gender differences in specific inflammatory pathways and proteins in patients with seasonal allergic rhinitis. Further studies are warranted to examine if such differences have diagnostic and therapeutic implications in allergic diseases.     

A module-based analytical strategy to identify novel disease-associated genes shows an inhibitory role for interleukin 7 Receptor in allergic inflammation

Background  

The identification of novel genes by high-throughput studies of complex diseases is complicated by the large number of potential genes. However, since disease-associated genes tend to interact, one solution is to arrange them in modules based on co-expression data and known gene interactions. The hypothesis of this study was that such a module could be a) found and validated in allergic disease and b) used to find and validate one ore more novel disease-associated genes.     

Hyperinsulinemia: effect on cardiac mass/function, angiotensin II receptor expression, and insulin signaling pathways

To investigate the association between hyperinsulinemia and cardiac hypertrophy, we treated rats with insulin for 7 wk and assessed effects on myocardial growth, vascularization, and fibrosis in relation to the expression of angiotensin II receptors (AT-R). We also characterized insulin signaling pathways believed to promote myocyte growth and interact with proliferative responses mediated by G protein-coupled receptors, and we assessed myocardial insulin receptor substrate-1 (IRS-1) and p110 alpha catalytic and p85 regulatory subunits of phospatidylinositol 3 kinase (PI3K), Akt, MEK, ERK1/2, and S6 kinase-1 (S6K1). Left ventricular (LV) geometry and performance were evaluated echocardiographically. Insulin decreased AT1a-R mRNA expression but increased protein levels and increased AT2-R mRNA and protein levels and phosphorylation of IRS-1 (Ser374/Tyr989), MEK1/2 (Ser218/Ser222), ERK1/2 (Thr202/Tyr204), S6K1 (Thr421/Ser424/Thr389), Akt (Thr308/Thr308), and PI3K p110 alpha but not of p85 (Tyr508). Insulin increased LV mass and relative wall thickness and reduced stroke volume and cardiac output. Histochemical examination demonstrated myocyte hypertrophy and increases in interstitial fibrosis. Metoprolol plus insulin prevented the increase in relative wall thickness, decreased fibrosis, increased LV mass, and improved function seen with insulin alone. Thus our data demonstrate that chronic hyperinsulinemia decreases AT1a-to-AT2 ratio and increases MEK-ERK1/2 and S6K1 pathway activity related to hypertrophy. These changes might be crucial for increased cardiovascular growth and fibrosis and signs of impaired LV function.     

Histological and histochemical studies of the gall bladder of the graylag goose (Anser anser)

ABSTRACT

We investigated the histological structure of the graylag goose (Anser anser) gall bladder. Sections of the gall bladder were stained with hematoxylin and eosin (H & E), Alcian blue (pH 2.5) for acid mucopolysaccharides, Gomori’s method for reticular fibers, Masson’s trichrome, periodic acid-Schiff (PAS) and Verhoeff’s elastin stain. The goose gall bladder was composed of a tunica mucosa, tunica muscularis and tunica adventitia or tunica serosa. The tunica mucosa formed regularly distributed simple isometric folds plus larger, less numerous, branched folds. The luminal surface was lined by tall columnar epithelial cells that stained for both acid and neutral mucopolysaccharides. The epithelial cells formed a discontinuous striated border of interdigitating microvilli on the luminal surface. Neither a lamina muscularis nor goblet cells were observed in the tunica mucosa. Unusual findings included branched mucosal folds, discontinuous microvilli and absence of an outer longitudinal layer in the tunica muscularis. No marked sex-associated differences were found. The general histochemical and histological structures of the graylag goose gall bladder are similar to those of birds such as chukar partridge and quail, but with some unique elements that may reflect differences in organ function.     

The role of S477N mutation in the molecular behavior of SARS-CoV-2 spike protein: An in-silico perspective

The attachment of SARA-CoV-2 happens between ACE2 and the receptor binding domain (RBD) on the spike protein. Mutations in this domain can affect the binding affinity of the spike protein for ACE2. S477N, one of the most common mutations reported in the recent variants, is located in the RBD. Today's computational approaches in biology, especially during the SARS-CoV-2 pandemic, assist researchers in predicting a protein's behavior in contact with other proteins in more detail. In this study, we investigated the interactions of the S477N-hACE2 in silico to find the impact of this mutation on its binding affinity for ACE2 and immunity responses using dynamics simulation, protein–protein docking, and immunoinformatics methods. Our computational analysis revealed an increased binding affinity of N477 for ACE2. Four new hydrogen and hydrophobic bonds in the mutant RBD-ACE2 were formed (with S19 and Q24 of ACE2), which do not exist in the wild type. Also, the protein spike structure in this mutation was associated with an increase in stabilization and a decrease in its fluctuations at the atomic level. N477 mutation can be considered as the cause of increased escape from the immune system through MHC-II.     

The formation of lipid droplets: possible role in the development of insulin resistance/type 2 diabetes

Neutral lipids are stored in so-called lipid droplets, which are formed as small primordial droplets at microsomal membranes and increase in size by a fusion process. The fusion is catalyzed by the SNARE proteins SNAP23, syntaxin-5 and VAMP4. SNAP23 is involved in the insulin dependent translocation of GLUT4 to the plasma membrane, and has an important role in the development of insulin resistance. Thus fatty acids relocalize SNAP23 from the plasma membrane (and the translocation of GLUT 4) to the interior of the cell giving rise to insulin resistance. Moreover this relocalization is seen in skeletal muscles biopsies from patients with type 2 diabetes compared to matched control. Thus a missorting of SNAP23 is essential for the development of insulin resistance.