Interaction of Cationic Carbosilane Dendrimers and Their siRNA Complexes with MCF-7 Cells

The application of siRNA in gene therapy is mainly limited because of the problems with its transport into cells. Utilization of cationic dendrimers as siRNA carriers seems to be a promising solution in overcoming these issues, due to their positive charge and ability to penetrate cell membranes. The following two types of carbosilane dendrimers were examined: CBD-1 and CBD-2. Dendrimers were complexed with pro-apoptotic siRNA (Mcl-1 and Bcl-2) and the complexes were characterized by measuring their zeta potential, circular dichroism and fluorescence of ethidium bromide associated with dendrimers. CBD-2/siRNA complexes were also examined by agarose gel electrophoresis. Both dendrimers form complexes with siRNA. Moreover, the cellular uptake and influence on the cell viability of the dendrimers and dendriplexes were evaluated using microscopic methods and XTT assay on MCF-7 cells. Microscopy showed that both dendrimers can transport siRNA into cells; however, a cytotoxicity assay showed differences in the toxicity of these dendrimers.     

Conjugation with Phospholipids as a Modification Increasing Anticancer Activity of Phenolic Acids in Metastatic Melanoma—In Vitro and In Silico Studies

Phenolic acids possess many beneficial biological activities, including antioxidant and anti-inflammatory properties. Unfortunately, their low bioavailability restricts their potential medical uses, as it limits the concentration of phenolic acids achievable in the organism. The conjugation with phospholipids constitutes one of the most effective strategies to enhance compounds bioavailability in biological systems. In the present study, the conjugates of anisic (ANISA) and veratric acid (VA) with phosphatidylcholine (PC) were investigated. Since both ANISA and VA are inhibitors of tyrosinase, a melanocyte enzyme, the expression of which increases during tumorigenesis, anticancer potential of the conjugates was tested in several metastatic melanoma cell lines. The conjugates proved to be antiproliferative, apoptosis-inducing and cell-cycle-affecting agents, selective for cancerous cells and not affecting normal fibroblasts. The conjugates substituted by ANISA and VA, respectively, at both the sn-1 and sn-2 positions of PC, appeared the most promising, since they were effective against the vast majority of metastatic melanoma cell lines. Additionally, the conjugation of phenolic acids to PC increased their antioxidant activity. Molecular modeling was employed for the first time to estimate the features of the investigated conjugates relevant to their anticancer properties and membrane permeation. Again, the conjugates substituted by phenolic acid at both the sn-1 and sn-2 positions of PC seemed to be presumably most bioavailable.     

Diminazene Aceturate Stabilizes Atherosclerotic Plaque and Attenuates Hepatic Steatosis in apoE-Knockout Mice by Influencing Macrophages Polarization and Taurine Biosynthesis

Atherosclerosis and nonalcoholic fatty liver disease are leading causes of morbidity and mortality in the Western countries. The renin–angiotensin system (RAS) with its two main opposing effectors, i.e., angiotensin II (Ang II) and Ang-(1–7), is widely recognized as a major regulator of cardiovascular function and body metabolic processes. Angiotensin-converting enzyme 2 (ACE2) by breaking-down Ang II forms Ang-(1–7) and thus favors Ang-(1–7) actions. Therefore, the aim of our study was to comprehensively evaluate the influence of prolonged treatment with ACE2 activator, diminazene aceturate (DIZE) on the development of atherosclerotic lesions and hepatic steatosis in apoE^−/− mice fed a high-fat diet (HFD). We have shown that DIZE stabilized atherosclerotic lesions and attenuated hepatic steatosis in apoE^−/− mice fed an HFD. Such effects were associated with decreased total macrophages content and increased α-smooth muscle actin levels in atherosclerotic plaques. Moreover, DIZE changed polarization of macrophages towards increased amount of anti-inflammatory M2 macrophages in the atherosclerotic lesions. Interestingly, the anti-steatotic action of DIZE in the liver was related to the elevated levels of HDL in the plasma, decreased levels of triglycerides, and increased biosynthesis and concentration of taurine in the liver of apoE^−/− mice. However, exact molecular mechanisms of both anti-atherosclerotic and anti-steatotic actions of DIZE require further investigations.     

Green TPUs from Prepolymer Mixtures Designed by Controlling the Chemical Structure of Flexible Segments

This study concerns green thermoplastic polyurethanes (TPU) obtained by controlling the chemical structure of flexible segments. Two types of bio-based polyether polyols—poly(trimethylene glycol)s—with average molecular weights ca. 1000 and 2700 Da were used (PO3G1000 and PO3G2700, respectively). TPUs were prepared via a two-step method. Hard segments consisted of 4,4′-diphenylmethane diisocyanates and the bio-based 1,4-butanodiol (used as a chain extender and used to control the [NCO]/[OH] molar ratio). The impacts of the structure of flexible segments, the amount of each type of prepolymer, and the [NCO]/[OH] molar ratio on the chemical structure and selected properties of the TPUs were verified. By regulating the number of flexible segments of a given type, different selected properties of TPU materials were obtained. Thermal analysis confirmed the high thermal stability of the prepared materials and revealed that TPUs based on a higher amount of prepolymer synthesized from PO3G2700 have a tendency for cold crystallization. An increase in the amount of PO3G1000 at the flexible segments caused an increase in the tensile strength and decrease in the elongation at break. Melt flow index results demonstrated that the increase in the amount of prepolymer based on PO3G1000 resulted in TPUs favorable in terms of machining.     

The Obscure Effect of Tribulus terrestris Saponins Plus Inulin on Liver Morphology,Liver Fatty Acids,Plasma Glucose,and Lipid Profile in SD Rats with and without Induced Type 2 Diabetes Mellitus

Diabetes is a predictor of nonalcoholic fatty liver disease (NAFLD). There are data suggesting that Tribulus terrestris (TT) saponins act as antidiabetic agents and protect against NAFLD. The effect of saponins may be increased by fermentable fibers such as inulin. The aim of the present study was to investigate the influence of TT saponins and TT saponins plus inulin on the plasma lipid profile and liver fatty acids of rats with induced diabetes mellitus type 2 (T2DM). The study was performed on 36 male Sprague–Dawley rats divided into two main groups: control and diabetic. Animals of the diabetic (DM) group were fed a high-fat diet and injected with streptozotocin (low doses). Animals of the control group (nDM) were on a regular diet and were injected with buffer. After the injections, the animals were split into subgroups: three non-diabetic (nDM): (i) control (c-C); (ii) saponin-treated rats (C-Sap); (iii) rats treated with saponins + inulin (C-Sap + IN), and three diabetic subgroups (DM): (iv) control (c-DM); (v) saponin-treated rats (DM-Sap); (vi) rats treated with saponins + inulin (DM-Sap + IN). Liver fatty acids were extracted and analyzed by gas chromatography, and plasma glucose and lipids were measured. The study showed significant changes in liver morphology, liver fatty acids, plasma lipid profile, and plasma glucose. In summary, supplementation with TT saponins or saponins with inulin for one month decreased the level of steatosis in rats with induced type 2 diabetes. Moreover, there were favorable effects on the plasma lipid profile in the rats. However, additional supplementation with inulin had a negative effect on liver morphology (with a microvesicular type of steatosis) in the non-diabetes group. Moreover, supplementation with inulin had a negative effect on plasma glucose in both diabetic and non-diabetic rats. These data show that a diet enriched with fermentable fibers reveals different effects in different organisms, and not all sources and forms of fiber are beneficial to health.     

Sustainable synthesis of cyclic carbonates from bio‐based polyether polyol: the structure characterization,rheological behaviour and thermal properties

The cycloaddition of CO₂ to epoxides represents a green efficient method to form bis(cyclic carbonate)s. The main purpose of the work reported in this paper was to examine the effect of the gas flow rate (20, 40, 60 and 100 mL min^–1) during carbonation on the conversion yield, chemical structure, rheological behaviour and thermal properties of the prepared compounds. A series of new bis(cyclic carbonate)s was obtained from bio‐based polyether polyol. The syntheses were performed in the absence of toxic solvents and the process did not require the use of elevated pressure. The progressive structural changes and the presence of characteristic chemical groups were monitored by attenuated total reflection Fourier transform infrared spectroscopy. The characterization of the structure by ¹H NMR and ¹³C NMR also confirmed the formation of cyclic carbonate moieties. The non‐Newtonian behaviour and the optimal mathematical model (Herschel–Bulkley) were verified by rheological measurements. The materials obtained could be used as a chemical intermediate to synthesize advanced materials based upon polyurethanes without using isocyanates. © 2019 Society of Chemical Industry     

Nonlinear Absorption of Submicrometer Grain‐Size Cobalt‐Doped Magnesium Aluminate Transparent Ceramics

Transparent cobalt‐doped magnesium aluminate spinel (Co:MgAl₂O₄) ceramics with a submicrometer grain size were prepared by spark plasma sintering. For the first time, the nonlinear absorption of Co:MgAl₂O₄ transparent ceramics was experimentally demonstrated. Both ground state absorption (σ_GSA) and excited state absorption (σ_ESA) were estimated using the solid‐state slow saturable absorber model based on absorption saturation measurements performed at 1.535 μm. σ_GSA and σ_ESA for 0.03 at.% Co:MgAl₂O₄ were found to be 4.1 × 10^?19 cm² and 4.0 × 10^?20 cm², respectively. In the case of 0.06 at.% Co:MgAl₂O₄ ceramics, σ_GSA = 2.6 × 10^?19 cm² and σ_ESA= 5.3 × 10^?20 cm² were determined.     

In Search of Concerted Strategies for Competitive and Resilient Regions

The European space-economy represents a complex system with a great internal heterogeneity, intensive socioeconomic interactions and differential growth trajectories among countries and regions. The present study aims to investigate the connectivity between spatial competitiveness and resilience in Europe and seeks to design an operational framework for concerted strategies of competitive and resilient regions. To assess the linkage between resilience and competitiveness, we have developed a new measure, viz. the Resilience and Competitiveness Index (RACI) as a function of two constituent sub-indices: Resilience and Competitiveness. This approach is tested on the basis of detailed data on European regions. The empirical results from 268 EU NUTS2 regions offer a solid anchor point for the proposed operational framework for concerted development strategies of competitive and resilient regions. Our research distinguishes and proposes several systematic types of concerted regional strategies according to the performance of a region measured by Resilience and Competiveness sub-indices. A key result of the study is the design of an operational constellation for strategic regional policy evaluation, with a major added value for policy- and decision-making purposes. The use of official data from Eurostat and of standard indicators in our research assures continuity and consistency with the official Regional Competitiveness Index (RCI) classification and measurement, so that policy makers are able to compare the performance of their regions over time and to develop proper concerted strategies accordingly. The clear evidence of a connectivity between regional competitiveness and resilience may help to develop a governance approach that balances competitiveness (mainly represented by productive assets) with resilience (mainly represented by sustainability and ecological awareness) and thus to deal with the complexity in socioeconomic systems.

     

Untargeted metabolomics reveals links between Tiger nut (Cyperus esculentus L.) and its geographical origin by metabolome changes associated with membrane lipids

Tiger nuts and tiger nut milk are well-known Valencian products, and step-by-step these tubers and the tuber-based beverage are becoming more and more relevant products in international markets. However, the increasing demand and success of Valencian tiger nuts did not allow protected designation of origin (PDO) tuber to supply the domestic and international markets. Therefore, the verification of the geographical origin is highly required. In this research, the main objective was to combine an advance analytical method and chemometrics tools in order to decipher the geographical origin of 45 tiger nut samples from (i) ‘Xufa de València’ PDO and (ii) African samples. The analytical method, based on solid-liquid extraction followed by ultra-high performance liquid chromatography coupled to high resolution tandem mass spectrometry (UHPLC-HRMS) metabolomics approach, highlighted sensitivity and wide linear dynamic range in order to simultaneously analyse polar and non-polar metabolites. After data processing, a pronounced sample clustering according to the geographical origin was clearly observed using unsupervised models, and supervised models revealed that tiger nuts lipidome was associated with the geographical origin. As a result, African samples highlighted an overexpression of phospholipids, such as phosphatidylethanolamine 34:1, and triacylgricerols crosslinked to environmental stress and alteration of membrane lipid compositions.