Trace identification of cysteine enantiomers based on an electrochemical sensor assembled from CuxS@SOD zeolite.

The nonchiral sensor concept based on a sodalite (SOD) zeolite loaded CuxS (CuxS@SOD) catalyst is proposed as a sensing platform for chiral cysteine (Cys) determination. Chiral Cys is analyzed by the difference of binding capacity between CuxS catalysts. The observed current in amperometric i-t curve (A i-t C) is always positive for the L-cysteine (L-Cys), while it is negative for the D-cysteine (D-Cys). Under differential pulse voltammetry (DPV) method, the characteristic current peak for the CuxS@SOD moves to right (positive potential position) with the addition of L-Cys while it moves to left (negative potential direction) with the addition of D-Cys, respectively. Cyclic voltammetry (CV) is consistent with DPV and discusses the diffusion control mechanism. In this work, the ultra-trace determination of cysteine enantiomers reaches the limit of detection (LOD) of 0.70 fM and 0.60 fM by the highly efficient CuxS catalyst restrained in the nanosized SOD zeolite cages of the opening window pores, respectively. The sensor opens up a novel potential prospect for achiral composite in the field of chiral recognition through electrochemical methods with extra-low concentration.

Photothermal and Acid-Responsive Fucoidan-CuS Bubble Pump Microneedles for Combined CDT/PTT/CT Treatment of Melanoma.

Transdermal cancer therapy faces great challenges in clinical practice due to the low drug transdermal efficiency and the unsatisfactory effect of monotherapy. Herein, we develop a novel bubble pump microneedle system (BPMN-CuS/DOX) by embedding sodium bicarbonate (NaHCO3) into hyaluronic acid microneedles (MNs) loaded with fucoidan-based copper sulfide nanoparticles (Fuc-CuS NPs) and doxorubicin (DOX). BPMN-CuS/DOX can generate CO2 bubbles triggered by an acidic tumor microenvironment for deep and rapid intradermal drug delivery. Fuc-CuS NPs exhibit excellent photothermal effect and Fenton-like catalytic activity, producing more reactive oxygen species (ROS) by photothermal therapy (PTT) and chemodynamic therapy (CDT), which enhances the antitumor efficacy of DOX and reduces the dosage of its chemotherapy (CT). Simultaneously, DOX increases intracellular hydrogen peroxide (H2O2) supplementation and promotes the sustained production of ROS. BPMN-CuS/DOX significantly inhibits melanoma both in vitro and in vivo by the combination of CDT, PTT, and CT. In short, our study significantly enhances the effectiveness of transdermal drug delivery by constructing BPMNs and provides a promising novel strategy for transdermal cancer treatment with multiple therapies.

Engineering Cu2-xS-conjugated upconverting nanocomposites for NIR-II light-induced enhanced chemodynamic/photothermal therapy of cancer.

The integration of chemodynamic therapy (CDT) and photothermal therapy (PTT) has played a huge role in improved anticancer treatments. Here, a novel multifunctional nanoplatform based on Cu2-xS conjugated NaYF4:Yb/Er@NaYF4:Yb upconversion nanoparticles (UCNPs) was proposed and designed. In the UCNPs-Cu2-xS nanocomposites, UCNPs with excellent luminescent properties and a high X-ray attenuation coefficient can serve as an upconversion luminescence (UCL) and computer tomography (CT) imaging contrast agent; meanwhile, Cu(II) in the Cu2-xS nanodots enables the nanocomposites to have a magnetic resonance imaging (MRI) ability owing to the presence of unpaired electrons. Moreover, the Cu2-xS nanodots with a strong absorbance in the NIR II biowindow not only could be employed as a stable photothermal agent under NIR laser irradiation, but also could be used as a photothermal-enhanced Fenton nanocatalyst to respond to over-expressed H2O2 in the tumor microenvironment (TME) and generate toxic hydroxyl radicals (˙OH) to effectively kill cancer cells. Furthermore, the UCNPs-Cu2-xS nanocomposites possess negligible cytotoxicity and a high photothermal conversion efficiency (43.8%) in the NIR-II biowindow (1064 nm), indicating that they possess great potential for the UCL/CT/MR multi-modal imaging guided synergistic enhanced CDT/PTT of cancer.

Guided screen for synergistic three-drug combinations.

Combinations of three or more drugs are routinely used in various medical fields such as clinical oncology and infectious diseases to prevent resistance or to achieve synergistic therapeutic benefits. The very large number of possible high-order drug combinations presents a formidable challenge for discovering synergistic drug combinations. Here, we establish a guided screen to discover synergistic three-drug combinations. Using traditional checkerboard and recently developed diagonal methods, we experimentally measured all pairwise interactions among eight compounds in Erwinia amylovora, the causative agent of fire blight. Showing that synergy measurements of these two methods agree, we predicted synergy/antagonism scores for all possible three-drug combinations by averaging the synergy scores of pairwise interactions. We validated these predictions by experimentally measuring 35 three-drug interactions. Therefore, our guided screen for discovering three-drug synergies is (i) experimental screen of all pairwise interactions using diagonal method, (ii) averaging pairwise scores among components to predict three-drug interaction scores, (iii) experimental testing of top predictions. In our study, this strategy resulted in a five-fold reduction in screen size to find the most synergistic three-drug combinations.

Clearable Black Phosphorus Nanoconjugate for Targeted Cancer Phototheranostics.

Therapeutic efficacy of synergistic photodynamic therapy (PDT) and photothermal therapy (PTT) is limited by complex conjugation chemistry, absorption wavelength mismatch, and inadequate biodegradability of the PDT-PTT agents. Herein, we designed biocompatible copper sulfide nanodot anchored folic acid-modified black phosphorus nanosheets (BP-CuS-FA) to overcome these limitations, consequently enhancing the therapeutic efficiency of PDT-PTT. In vitro and in vivo assays reveal good biocompatibility and commendable tumor inhibition efficacy of the BP-CuS-FA nanoconjugate because of the synergistic PTT-PDT mediated by near-infrared laser irradiation. Importantly, folic acid unit could target folate receptor overexpressed cancer cells, leading to enhanced cellular uptake of BP-CuS-FA. BP-CuS-FA also exhibits significant contrast effect for photoacoustic imaging, permitting its in vivo tracking. The photodegradable character of BP-CuS-FA is associated with better renal clearance after the antitumor therapy in vivo. The present research may facilitate further development on straightforward approaches for targeted and imaging-guided synergistic PDT-PTT of cancer.

Synthesis of DNA-templated copper nanoparticles with enhanced fluorescence stability for cellular imaging.

Fluorescence of DNA-templated copper nanoparticles (DNA-CuNPs) is not stable over time which limits applications in cellular imaging. This is due to the presence of oxygen during synthesis which oxidizes Cu(0) to Cu(II) and also produces the free hydroxyl radical. The authors have prepared DNA-CuNPs with enhanced temporal stability of fluorescence by optimizing the reaction conditions so as to minimize the deleterious effects of oxygen. The operational lifetime of DNA-CuNPs was increased from 25 min to 200 min. Fluorescence spectra of DNA-CuNPs in optimized condition show an emission peak at 650 nm when excited at 340 nm. DNA-CuNPs synthesized in this manner were used for cell imaging. As a proof of concept, the nucleus of a human colon cell line (HCT116) was stained. The method does not involve any chemicals other that copper sulfate and ascorbate. This new approach for generating DNA-CuNPs improves imaging of biological processes and provides a basis for developing other types of DNA-templated nanomaterials. Graphical abstract Schematic presentation of the formation of fluorescent DNA-templated copper nanoparticles (DNA-CuNPs). A large amount of ascorbate provides long operational lifetime for cellular imaging under the condition exposed to oxygen. *Asc- and **DHA stand for ascorbate and dehydroascorbic acid.

Photodegradation of 17ß-estradiol on silica gel and natural soil by UV treatment.

This paper evaluates the UV photodegradation of 17ß-estradiol (E2) on silica gel and in natural soil with different soil components. Silica gel was chosen as a stable and pure support to simulate the photochemical behavior of E2 on the surface of natural soil. Ultraviolet light, rather than visible light, was confirmed to play a decisive role in the photodegradation of E2 on silica gel. The effect of three soil components, including humic acid (HA), inorganic salts, and relative humidity (RH), on the photochemical behavior of E2 on silica gel or soil under UV irradiation was then evaluated. Two HA concentrations (10 and 20 mg g-1) and three salts (ferric sulfate, copper sulfate and sodium carbonate) were observed to obviously inhibit the degradation of E2 on silica gel. Interestingly, nitrate was found to obviously improve the removal efficiency of E2. Both too-dry and too-wet conditions obviously reduced the removal rate of E2, and the optimum relative humidity (RH) value was found to be approximately about 35% (30 °C). Furthermore, twenty intermediate products and two major pathways were proposed to describe the transformation processes of E2 treated by UV irradiation, among which oligomers were found to be the major intermediate products before complete mineralization. The efficient UV removal of E2 on silica gel and natural soil suggested a feasible strategy to remediate E2 contaminated soil.

3D-printing porosity: A new approach to creating elevated porosity materials and structures.

We introduce a new process that enables the ability to 3D-print high porosity materials and structures by combining the newly introduced 3D-Painting process with traditional salt-leaching. The synthesis and resulting properties of three 3D-printable inks comprised of varying volume ratios (25:75, 50:50, 70:30) of CuSO4 salt and polylactide-co-glycolide (PLGA), as well as their as-printed and salt-leached counterparts, are discussed. The resulting materials are comprised entirely of PLGA (F-PLGA), but exhibit porosities proportional to the original CuSO4 content. The three distinct F-PLGA materials exhibit average porosities of 66.6-94.4%, elastic moduli of 112.6-2.7 MPa, and absorbency of 195.7-742.2%. Studies with adult human mesenchymal stem cells (hMSCs) demonstrated that elevated porosity substantially promotes cell adhesion, viability, and proliferation. F-PLGA can also act as carriers for weak, naturally or synthetically-derived hydrogels. Finally, we show that this process can be extended to other materials including graphene, metals, and ceramics. STATEMENT OF SIGNIFICANCE: Porosity plays an essential role in the performance and function of biomaterials, tissue engineering, and clinical medicine. For the same material chemistry, the level of porosity can dictate if it is cell, tissue, or organ friendly; with low porosity materials being far less favorable than high porosity materials. Despite its importance, it has been difficult to create three-dimensionally printed structures that are comprised of materials that have extremely high levels of internal porosity yet are surgically friendly (able to handle and utilize during surgical operations). In this work, we extend a new materials-centric approach to 3D-printing, 3D-Painting, to 3D-printing structures made almost entirely out of water-soluble salt. The structures are then washed in a specific way that not only extracts the salt but causes the structures to increase in size. With the salt removed, the resulting medical polymer structures are almost entirely porous and contain very little solid material, but the maintain their 3D-printed form and are highly compatible with adult human stem cells, are mechanically robust enough to use in surgical manipulations, and can be filled with and act as carriers for biologically active liquids and gels. We can also extend this process to three-dimensionally printing other porous materials, such as graphene, metals, and even ceramics.

The impact of the oxygen scavenger on the dose-rate dependence and dose sensitivity of MAGIC type polymer gels.

Recent developments in radiation therapy aimed at more precise dose delivery along with higher dose gradients (dose painting) and more efficient dose delivery with higher dose rates e.g. flattening filter free (FFF) irradiation. Magnetic-resonance-imaging based polymer gel dosimetry offers 3D information for precise dose delivery techniques. Many of the proposed polymer gels have been reported to exhibit a dose response, measured as relaxation rate ΔR2(D), which is dose rate dependent. A lack of or a reduced dose-rate sensitivity is very important for dosimetric accuracy, especially with regard to the increasing clinical use of FFF irradiation protocols with LINACs at high dose rates. Some commonly used polymer gels are based on Methacrylic-Acid-Gel-Initiated-by-Copper (MAGIC). Here, we report on the dose sensitivity (ΔR2/ΔD) of MAGIC-type gels with different oxygen scavenger concentration for their specific dependence on the applied dose rate in order to improve the dosimetric performance, especially for high dose rates. A preclinical x-ray machine ('Yxlon', E = 200 kV) was used for irradiation to cover a range of dose rates from low [Formula: see text] min = 0.6 Gy min-1 to high [Formula: see text] max = 18 Gy min-1. The dose response was evaluated using R2-imaging of the gel on a human high-field (7T) MR-scanner. The results indicate that all of the investigated dose rates had an impact on the dose response in polymer gel dosimeters, being strongest in the high dose region and less effective for low dose levels. The absolute dose rate dependence [Formula: see text] of the dose response in MAGIC-type gel is significantly reduced using higher concentrations of oxygen scavenger at the expense of reduced dose sensitivity. For quantitative dose evaluations the relative dose rate dependence of a polymer gel, normalized to its sensitivity is important. Based on this normalized sensitivity the dose rate sensitivity was reduced distinctly using an increased oxygen scavenger concentration with reference to standard MAGIC-type gel formulation at high dose rate levels. The proposed gel composition with high oxygen scavenger concentration exhibits a larger linear active dose response and might be used especially in FFF-radiation applications and preclinical dosimetry at high dose rates. We propose in general to use high dose rates for calibration and evaluation as the change in relative dose sensitivity is reduced at higher dose rates in all of the investigated gel types.

Sub-lethal effects of waterborne exposure to copper nanoparticles compared to copper sulphate on the shore crab (Carcinus maenas).

The toxicity of soluble copper (Cu) to marine organisms is reasonably well described. However, the hazard of Cu engineered nanomaterial (ENMs) is poorly understood. The aim of the present study was to compare the toxicity of Cu ENMs to Cu as CuSO4 in the shore crab, Carcinus maenas. The crabs were exposed via the water using a semi-static approach to 0.2 or 1mgL-1 of Cu ENMs or 1mgL-1 of Cu as CuSO4. Gills, hepatopancreas, chela muscle and haemolymph were collected at days 0, 4 and 7 for the body burden of Cu, histology and biochemical analysis [thiobarbituric acid reactive substances (TBARS) and total glutathione (GSH)]. Nominal exposure concentrations of both the ENMs and the metal salt were maintained at over 80% in each treatment throughout the experiment. By day 7, 54% mortality was recorded in the 1mgL-1 CuSO4 treatment, compared to just 21% in the 1mgL-1 Cu ENM-exposed crabs. The target organs for Cu accumulation were similar for both forms of Cu with highest concentrations in the gills, particularly the posterior gills; followed by the hepatopancreas, and with the lowest concentrations in the chela muscle. No changes were observed in the osmolarity of the haemolymph (ANOVA, P>0.05). TBARS were measured as an indicator of lipid peroxidation and showed the greatest change in the anterior and posterior gills and hepatopancreas of animals exposed to 1mgL-1 Cu ENMs (ANOVA or Kruskal-Wallis, P<0.05). No statistically significant changes in total GSH were observed (ANOVA, P>0.05; n=6 crabs per treatment). Histological analysis revealed organ injuries in all treatments. The types of pathologies observed in the Cu ENM treatments were broadly similar to those of the Cu as CuSO4 treatment. Overall, the target organs and Cu accumulation from Cu ENMs were comparable to that following exposure to Cu as CuSO4, and although there were some differences in the sub-lethal effects, the metal salt was more acutely toxic.

Fungal Pretreatment of Sweet Sorghum Bagasse with Combined CuSO4-Gallic Acid Supplement for Improvement in Lignin Degradation, Selectivity, and Enzymatic Saccharification.

Sweet sorghum (Sorghum sp.) has high biomass yield. Hydrolysis of lignocellulosic sweet sorghum bagasse (SSB) to fermentable sugar could be useful for manufacture of biofuel or other fermentation products. Pretreatment of lignocellulosic biomass to degrade lignin before enzymatic hydrolysis is a key step. Fungal pretreatment of SSB with combined CuSO4-gallic acid supplements in solid-state fermentation (SSF) to achieve higher lignin degradation, selectivity value (SV), and enzymatic hydrolysis to sugar was studied. Coriolus versicolor was selected due to high activities of ligninolytic enzymes laccase, lignin peroxidase (LiP), manganese peroxidase (MnP), polyphenol oxidase (PPO), and arylalcohol oxidase (AAO) and low activities of cellulolytic enzymes CMCase, FPase, and ß-glucosidase with high lignin degradation and SV in 20 days. CuSO4/gallic acid increased the activities of ligninolytic enzymes resulting in enhanced lignin degradations and SVs. Cumulative/synergistic effect of combined supplements further increased the activities of laccase, LiP, MnP, PPO, and AAO by 7.6, 14.6, 2.67, 2.06, and 2.15-folds, respectively (than control), resulting in highest lignin degradation 31.1 ± 1.4% w/w (1.56-fold) and SV 2.33 (3.58-fold). Enzymatic hydrolysis of pretreated SSB yielded higher (~2.2 times) fermentable sugar. The study showed combined supplements can improve fungal pretreatment of lignocellulosic biomass. XRD, SEM, FTIR, and TGA/DTG of SSB confirmed the results.

Copper oxide nanoparticles and copper sulphate act as antigenotoxic agents in drosophila melanogaster.

The biological reactivity of metal and metal oxide nanomaterials is attributed to their redox properties, which would explain their pro- or anti-cancer properties depending on exposure circumstances. In this sense, copper oxide nanoparticles (CuONP) have been proposed as a potential anti-tumoral agent. The aim of this study was to assess if CuONP can exert antigenotoxic effects using Drosophila melanogaster as an in vivo model. Genotoxicity was induced by two well-known genotoxic compounds, namely potassium dichromate (PD) and ethyl methanesulfonate (EMS). The wing-spot assay and the comet assay were used as biomarkers of genotoxic effects. In addition, changes in the expression of Ogg1 and Sod genes were determined. The effects of CuONP cotreatment were compared with those induced by copper sulfate (CS), an agent releasing copper ions. Using the wing-spot assay, CuONP and CS were not able to reduce the genotoxic effects of EMS exposure, but had the ability to decrease the effects induced by PD, reducing the frequency of mutant twin-spots that arise from mitotic recombination. In addition, CuONP and CS were able to reduce the DNA damage induced by PD as determined by the comet assay. In general, similar qualitative antigenotoxic effects were obtained with both copper compounds. The antigenotoxic effects of environmentally relevant and non-toxic doses of CuONP and CS may be explained by their ability to partially restore the expression levels of the repair gene Ogg1 and the antioxidant gene Cu,ZnSod, both of which are inhibited by PD treatment. Environ. Mol. Mutagen. 58:46-55, 2017. © 2016 Wiley Periodicals, Inc.

CuSO4/H2O2-Triggered Polydopamine/Poly(sulfobetaine methacrylate) Coatings for Antifouling Membrane Surfaces.

Mussel-inspired polydopamine (PDA) coatings have been broadly exploited for constructing functional membrane surfaces. One-step codeposition of PDA with antifouling polymers, especially zwitterionic polymers, has been regarded as a promising strategy for fabricating antifouling membrane surfaces. However, one challenge is that the codeposition is usually a slow process over 10 h or even several days. Herein, we report that CuSO4/H2O2 is able to notably accelerate the codeposition process of PDA with poly(sulfobetaine methacrylate) (PSBMA). In our case, PSBMA is facilely anchored to the polypropylene microporous membrane (PPMM) surfaces within 1 h with the assistance of PDA because of its strong interfacial adhesion. The PDA/PSBMA-coated PPMMs show excellent surface hydrophilicity, high water permeation flux (7506 ± 528 L/m2·h at 0.1 MPa), and an outstanding antifouling property. Moreover, the antifouling property is maintained after the membranes are treated with acid and alkali solutions as well as organic solvents. To recap, it provides a facile, universal, and time-saving strategy for exploiting high-efficiency and durable antifouling membrane surfaces.

Copper nanoclusters trigger muscle cell apoptosis and atrophy in vitro and in vivo.

Copper nanoclusters (CuNCs) are increasingly being used in nanomedicine owing to their utility in cellular imaging and as catalysts. Additionally, nanotoxicology research of CuNCs is gaining attention. We report here the synthesis and characterization of CuNCs and their cytotoxic impact on muscle cells. A simple protein-directed synthesis of stable CuNCs was prepared, using bovine serum albumin as the stabling agent. Physicochemical characterization of the synthesized CuNCs was performed using transmission electron microscopy. To evaluate the in vitro cytotoxicity, C2C12 cells were exposed to increasing doses (from 0.1 to 50 µg ml(-1)) of CuNCs. CuNCs affected the viability of C2C12 cells in a dose-dependent manner, as detected by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide and a lactate dehydrogenase release assay. Further studies indicated that CuNCs induced the formation of reactive oxygen species and decreased the activities of catalase and glutathione. CuNC treatment decreased the mitochondrial membrane potential and induced apoptosis, accompanied by an increase in the protein expression ratio of Bax/Bcl-2 and caspase-3/9 activity in C2C12 cells. CuNCs treatment resulted in atrophy of the C2C12 myotubes, which was characterized by the increased expression of atrophy-related genes, such as atrogin-1 and MuRF1. Finally, CuNCs induce morphological atrophy of primary muscle cells and mouse gastrocnemius muscle. Taken together, these results suggest that exposure to CuNCs may be a risk factor for the skeletal muscle system.

Generation of Scalable, Metallic High-Aspect Ratio Nanocomposites in a Biological Liquid Medium.

The goal of this protocol is to describe the synthesis of two novel biocomposites with high-aspect ratio structures. The biocomposites consist of copper and cystine, with either copper nanoparticles (CNPs) or copper sulfate contributing the metallic component. Synthesis is carried out in liquid under biological conditions (37 °C) and the self-assembled composites form after 24 hr. Once formed, these composites are highly stable in both liquid media and in a dried form. The composites scale from the nano- to micro- range in length, and from a few microns to 25 nm in diameter. Field emission scanning electron microscopy with energy dispersive X-ray spectroscopy (EDX) demonstrated that sulfur was present in the NP-derived linear structures, while it was absent from the starting CNP material, thus confirming cystine as the source of sulfur in the final nanocomposites. During synthesis of these linear nano- and micro-composites, a diverse range of lengths of structures is formed in the synthesis vessel. Sonication of the liquid mixture after synthesis was demonstrated to assist in controlling average size of the structures by diminishing the average length with increased time of sonication. Since the formed structures are highly stable, do not agglomerate, and are formed in liquid phase, centrifugation may also be used to assist in concentrating and segregating formed composites.

Formation of copper nanoparticles on poly(thymine) through surface-initiated enzymatic polymerization and its application for DNA detection.

Poly(thymine) (polyT) and double-stranded DNA (dsDNA) can act as efficient templates for the formation of copper nanoparticles (CuNPs) at a low concentration of CuSO4, and the formed CuNPs emit excellent fluorescence. In this work, we demonstrated a new and facile strategy for the highly sensitive and selective detection of DNA on streptavidin-functionalized magnetic beads (SA-MB) using DNA-templated CuNPs as the fluorescent probe. Target DNA (tDNA) was hybridized with the capture DNA that was immobilized on the surface of SA-MB. Surface initiated enzymatic polymerization (SIEP) was employed as the signal amplification method to generate the polyT at the 3' end of tDNA for the formation of CuNPs. The incorporation of polyT by SIEP resulted in ∼35.7 fold signal amplification compared to the dsDNA after hybridization without SIEP. A dose-response curve for detection of DNA was obtained, with a linear dynamic range of 0.1 nM to 10 nM. We showed that this method has a low pM limit of detection (LOD 98.2 pM) and it is also very sensitive to the mismatch type in a specific DNA sequence. In addition, it avoids rigorously controlled temperature, complex synthesis of the fluorescent probe and prelabeling of DNA strands and eliminates the use of sophisticated experimental techniques and equipment. Armed with these intriguing properties, the proposed system could provide an efficient tool for early diagnosis and risk assessment of malignancy.

Modeling the retention mechanism for high-performance liquid chromatography with a chiral ligand mobile phase and enantioseparation of mandelic acid derivatives.

The chromatographic retention mechanism describing relationship between retention factor and concentration of Cu(2+) (l-phenylalanine)2 using chiral ligand mobile phase was investigated and eight mandelic acid derivatives were enantioseparated by chiral ligand exchange chromatography. The relationship between retention factor and concentration of the Cu(2+) (l-phenylalanine)2 complex was proven to be in conformity with chromatographic retention mechanism in which chiral discrimination occurred both in mobile and stationary phase. Different copper(II) salts, chiral ligands, organic modifier, pH of aqueous phase, and conventional temperature on retention behavior were optimized. Eight racemates were successfully enantioseparated on a common reversed-phase column with an optimized mobile phase composed of 6 mmol/L of l-phenylalanine or N,N-dimethyl-l-phenylalanine and 3 mmol/Lof copper(II) acetate or copper(II) sulfate aqueous solution and methanol.

Nanoparticles of copper stimulate angiogenesis at systemic and molecular level.

Copper is a key element affecting blood vessel growth and muscle development. However, the ions released from Cu salts are toxic. Given their specific physicochemical properties, nanoparticles of Cu (NanoCu) may have different bioactivity and affect the development of blood vessel and muscles in a different manner than Cu salts. The objective of the study was to evaluate the influence of NanoCu on embryo development and angiogenesis at the systemic and molecular level, in experiments using a chick embryo model. Fertilized chicken eggs were divided into a control group, and groups injected with a placebo, CuSO4 or NanoCu. Embryo development at the whole body level and molecular indices using an embryo chorioallantoic membrane model were measured during embryogenesis. The present study indicated for the first time that NanoCu have pro-angiogenic properties at the systemic level, to a greater degree than CuSO4 salt. The properties of NanoCu were confirmed at the molecular level, demonstrating significant effects on mRNA concentration and on mRNA gene expression of all pro-angiogenic and pro-proliferative genes measured herein.

Effect of Copper Sulfate on Expression of Endogenous L1 Retrotransposons in HepG2 Cells (Hepatocellular Carcinoma).

The long interspersed element-1 (LINE-1 or L1) constitutes approximately 17% of human genome. The expression of these elements is deregulated upon exposure to environmental exposures resulting to genomic instability and cancer promotion. The effect of copper as essential elements in regulation of L1 expression remained to be elucidated. Using non-cytotoxic concentrations of the copper, the expression of endogenous L1 was analyzed by qPCR after 6 days of copper pretreatment in human hepatocellular carcinoma cells (HepG2). The results indicated that the expression of active L1 elements are significantly downregulated at concentrations of 12.5, 25, and 50 µM (p < 0.005). Our data imply that low-level copper exposure may have a protective effect to suppress the induction of L1 activity and decrease incidence of cancer-associated L1 mutagenesis. If this achievement is confirmed by further studies, it can be applied in the long-term goals of cancer prevention.