Gene expression profile of immunoregulatory cytokines secreted from bone marrow and adipose derived human mesenchymal stem cells in early and late passages

Molecular Biology Reports - Mesenchymal Stem Cells (MSCs) have therapeutic potential in a variety of diseases; however, the safety and efficacy of their use remain ambiguous. Clinical applications...     

Exploring the interactions of a Tb(III)–quercetin complex with serum albumins (HSA and BSA): spectroscopic and molecular docking studies

Serum albumins (human serum albumin (HSA) and bovine serum albumin (BSA), two main circulatory proteins), are globular and monomeric macromolecules in plasma that transport many drugs and compounds. In the present study, we investigated the interactions of the Tb(III)–quercetin (Tb–QUE) complex with HSA and BSA using common spectroscopic techniques and a molecular docking study. Fluorescence data revealed that the inherent fluorescence emission of HSA and BSA was markedly quenched by the Tb–QUE complex through a static quenching mechanism, confirming stable complex formation (a ground‐state association) between albumins and Tb–QUE. Binding and thermodynamic parameters were obtained from the fluorescence spectra and the related equations at different temperatures under biological conditions. The binding constants (K_b) were calculated to be 0.8547 × 10³ M^?1 for HSA and 0.1363 × 10³ M^?1 for BSA at 298 K. Also, the number of binding sites (n) of the HSA/BSA–Tb–QUE systems was obtained to be approximately 1. Thermodynamic data calculations along with molecular docking results indicated that electrostatic interactions have a main role in the binding process of the Tb–QUE complex with HSA/BSA. Furthermore, molecular docking outputs revealed that the Tb–QUE complex has high affinity to bind to subdomain IIA of HSA and BSA. Binding distances (r) between HSA–Tb–QUE and BSA–Tb–QUE systems were also calculated using the Forster (fluorescence resonance energy transfer) method. It is expected that this study will provide a pathway for designing new compounds with multiple beneficial effects on human health from the phenolic compounds family such as the Tb–QUE complex.     

Designing of a Novel Fusion Protein Vaccine Candidate Against Human Visceral Leishmaniasis (VL) Using Immunoinformatics and Structural Approaches

Leishmaniasis is caused by an obligate intracellular protozoan parasite. The clinical forms of leishmaniasis differ from cutaneous leishmaniasis, mucocutaneous leishmaniasis and visceral leishmaniasis (VL) which depend on the parasite species and the host’s immune responses. There are significant challenges to the available anti-leishmanial drug therapy, particularly in severe forms of disease, and the rise of drug resistance has made it more difficult. Currently, no licensed vaccines have been introduced to the market for the control and elimination of VL. A potential target for use in candidate vaccines against leishmaniasis has been shown to be leishmania Kinetoplastid membrane protein-11 (KMP-11) antigen. In this study, we chose KMP-11 antigen as target antigen in our vaccine construct. In addition, B-type flagellin (fliC) was used as an adjuvant for enhancing vaccine immunogenicity. The GSGSGSGSGSG linker was applied to link the KMP-11 antigen and fliC (KMP-11-fliC) to construct our fusion protein. Bioinformatics approaches such as; 3D homology modeling, CTL, B-cell, MHC class I and II epitopes prediction, allergenicity, antigenicity evaluations, molecular docking, fast simulations of flexibility of docked complex and in silico cloning were employed to analysis and evaluation of various properties of the designed fusion construct. Computational results showed that our engineered structure has the potential for proper stimulation of cellular and humoral immune responses against VL. Consequently, it could be proposed as a candidate vaccine against VL according to these data and after verifying the efficacy of the candidate vaccine through in vivo and in vitro immunological tests.

     

Design and In Silico Evaluation of a Novel Cyclic Disulfide-Rich anti-VEGF Peptide as a Potential Antiangiogenic Drug

International Journal of Peptide Research and Therapeutics - The vascular endothelial growth factor (VEGF) signaling pathway has a crucial role in regulating tumor angiogenesis. VEGF-A shows...     

Energy-aware routing considering load balancing for SDN: a minimum graph-based Ant Colony Optimization

Software-Defined Network (SDN) technology is a network management approach that facilitates a high level of programmability and centralized manageability. By leveraging the control and data plane separation, an energy-aware routing model could be easily implemented in the networks. In the present paper, we propose a two-phase SDN-based routing mechanism that aims at minimizing energy consumption while providing a certain level of QoS for the users’ flows and realizing the link load balancing. To reduce the network energy consumption, a minimum graph-based Ant Colony Optimization (ACO) approach is used in the first phase. It prunes and optimizes the network tree by turning unnecessary switches off and providing an energy-minimized sub-graph that is responsible for the network existing flows. In the second phase, an innovative weighted routing approach is developed that guarantees the QoS requirements of the incoming flows and routes them so that to balance the loads on the links. We validated our proposed approach by conducting extensive simulations on different traffic patterns and scenarios with different thresholds. The results indicate that the proposed routing method considerably minimizes the network energy consumption, especially for congested traffics with mice-type flows. It can provide effective link load balancing while satisfying the users’ QoS requirements.

     

Monitored whole gene in vitro evolution of an anti-hRaf-1 affibody molecule towards increased binding affinity

The use of library technologies for the generation of affinity proteins often includes an affinity maturation step, based on the construction of secondary libraries from which second generation variants with improved affinities are selected. Here, we describe for the first time the affinity maturation of affibody molecules based on step-wise in vitro molecular evolution, involving cycles of error-prone PCR (epPCR) amplification for the introduction of diversity over the entire 58-residue three-helix bundle structure and ribosome display (RD) for the selection of improved variants. The model affibody molecule for the process was Z(RAF322), binding with a 1.9μm equilibrium dissociation constant (K(D)) to human Raf-1 (hRaf-1), a protein kinase of central importance in the MAPK/ERK proliferation pathway. The molecular evolution process was followed on both gene and protein levels via DNA sequencing and a biosensor-based binding analysis of pools of selected variants. After two cycles of diversification and selection, a significant increase in binding response of selected pools was seen. DNA sequencing showed that a dominant alanine to valine substitution had been effectively enriched, and was found in 83% of all selected clones, either alone or in combination with other enriched substitutions. The evolution procedure resulted in variants showing up to 26-fold increases in affinity to the hRaf-1 target. Noteworthy, for the two variants showing the highest affinities, substitutions were also found in affibody framework positions, corresponding to regions of the protein domain not addressed by traditional affibody molecule affinity maturation strategies. Interestingly, thermal melting point (T(m)) analyses showed that an increased affinity could be associated with both higher and lower T(m) values. All investigated variants showed excellent refolding properties and selective binding to hRaf-1, as analysed using a multiplexed bead-based binding assay, making them potentially valuable affinity reagents for cell biology studies.     

Alkyl esters of hydroxycinnamic acids with improved antioxidant activity and lipophilicity protect PC12 cells against oxidative stress

Hydroxycinnamic acids (HCAs) are phenolic compounds present in dietary plants, which possess considerable antioxidant activity. In order to increase the lipophilicity of HCAs, with the aim of improving their cellular absorption and expansion of their use in lipophilic media, methyl, ethyl, propyl and butyl esters of caffeic acid and ferulic acid have been synthesized. All caffeate esters had a slightly lower DPPH IC(50) (13.5-14.5 μM) and higher ferric reducing antioxidant power (FRAP) values (1490-1588 mM quercetin/mole [mMQ/mole]) compared to caffeic acid (16.6 μM and 1398 mMQ/mole, respectively) in antioxidant assays. In contrast, ferulate esters were less active in DPPH (56.3-74.7 μM) and FRAP assays (193-262 mMQ/mole) compared to ferulic acid (44.6 μM and 324 mMQ/mole, respectively). Redox properties of HCAs were in line with their antioxidant capacities, so that compounds with higher antioxidant activities had lower oxidation potentials. Measurement of partition coefficients disclosed the higher lipophilicity of the esters compared to parent compounds. All esters of caffeic acid significantly inhibited hydrogen peroxide-induced neuronal PC12 cell death assessed by MTT assay at 5 and 25 μM. However, caffeic acid, ferulic acid and ferulate esters were not able to protect the cells. In conclusion, these findings suggest that alkyl esterification of some HCAs augments their antioxidant properties as well as their lipophilicity and as a consequence, improves their cell protective activity against oxidative stress. These compounds could have useful applications in conditions where oxidative stress plays a pathogenic role.     

Effects of long-term cortisol treatments on gonadal development, sex steroids levels and ovarian cortisol content in cultured great sturgeon Huso huso

The objective of this study was to examine the effect of cortisol implantations on gonadal development, sex steroid levels, and ovarian cortisol content in cultured great sturgeon Huso huso. Three groups of 5 fish for each treatment were considered. The experimental groups included: control (capsules containing cocoa butter alone), low cortisol (C(5); 5mg cortisol/kg body mass+cocoa butter) and, high cortisol (C(50); 50mg cortisol/kg body mass+cocoa butter). The capsules containing hormones and cocoa butter were intraperitoneally implanted into 3-year-old female fish at pre-vitellogenic stage (mean initial body mass 6809.7 ± 73 g) every 6 weeks over a 6-month period from January to June. The serum levels of cortisol, glucose, cholesterol and sex steroids (testosterone and 17β-estradiol) were determined at the initial time and three weeks after each implantation. Oocyte histological characteristics (the diameter and area of the oocyte, the diameter and area of the nucleus and the ratio of the nucleus area to the oocyte area) were measured at the end of the experiment and compared to those at the initial time. Ovarian cortisol content was measured at the end of the experiment. The results showed that serum cortisol levels varied in a dose-independent manner, so that the highest cortisol concentrations were observed in C(5)-treated fish throughout the experiment. Serum glucose levels were significantly higher in cortisol-treated groups than those in the control group. The high dose of cortisol elicited a significant constant increase in serum cholesterol concentrations. Fish implanted with the high cortisol dose showed significant declines in serum testosterone and 17β-estradiol concentrations throughout the experiment. No significant differences were found in oocyte histological characteristics among experimental groups. The cortisol implants elicited a dose-dependent increase in ovarian cortisol content. At the end of trial, body-growth indices were the lowest in C(50)-implanted fish, while the low cortisol dose had no effect on growth relative to the controls. These results indicated that chronic stress induced by cortisol implantation in great sturgeon suppressed gonadal steroidogenesis and somatic growth but had no effect on ovarian growth and development.