Selenium is an essential trace element in the diet, required for maintenance of health and growth; however, its toxicity could cause serious damage depending on dose and chemical form. Selenium nanoparticles (SeNPs) represent what we believe to be a novel prospect for nutritional supplementation because of their lower toxicity and ability to gradually release selenium after ingestion. In this review, we discuss various forms and types of SeNPs, as well as the way they are synthesized. We also discuss absorption and bioavailability of nanoparticles within the organism. SeNPs demonstrate anticancer and antimicrobial properties that may contribute to human health, not only as dietary supplements, but also as therapeutic agents.

• Klíčová slova
• Antimicrobial activity, Cancer, Diet, Nanoselenium, Supplementation, Toxicity,
• MeSH
• antiinfekční látky farmakologie   MeSH
• lidé MeSH
• nanočástice * MeSH
• potravní doplňky * MeSH
• protinádorové látky farmakologie   MeSH
• selen aplikace a dávkování   farmakologie   MeSH
• stopové prvky aplikace a dávkování   farmakologie   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• přehledy MeSH
• Názvy látek
• antiinfekční látky MeSH
• protinádorové látky MeSH
• selen MeSH
• stopové prvky MeSH

Selenium is an essential compound which can influence the fertility of boars by a greater margin. In past decades, research was mainly focused on a bioavailability of various selenium forms and the effect on semen quality. Recently, nanotechnology has expanded the possibilities of selenium supplementation research. Twenty-one Duroc boars (three groups with seven boars each) were included in this experiment with the first group being a control group with no selenium supplementation, and the second group being supplemented with 0.3 mg Se/kg of selenium in inorganic form of Na2SeO3. The third group was supplemented with selenium nanoparticles (100 nm) at the same dose as that of the second group. The experiment lasted for 126 days (three spermatogenesis cycles of boars) and the antioxidant parameters of boar semen were analysed at 42, 84 and 126 days, respectively. The antioxidant parameters (DPPH, FRAP, DMPD, GSH, GSSG) were not influenced by both Se2NO3 and selenium nanoparticle supplementation during this experiment. At the end of the monitored period, significantly higher (p < 0.004) antioxidant readings were observed by using the ABTS method but not the DPPH, DMPD and FRAP methods on the supplemented groups compared to the control. Moreover, selenium-nanoparticle-supplemented groups showed elevated glutathione peroxidase activity in the seminal fluid (p < 0.008). However, the selenium nanoparticle supplementation has not shown an improving effect on sperm quality. This could be considered as a safe alternative to inorganic selenium as well as having a potential to enhance the antioxidant properties of the semen of boars.

• Klíčová slova
• antioxidants, boars, nanoparticles, selenium, semen,
• Publikační typ
• časopisecké články MeSH

BACKGROUND: Selenium is an essential element; however, at higher doses, it can be toxic. Therefore, alternative nanotechnological solutions are required to overcome toxicological issues, rather than conventional alternatives. Nanoparticles show new and promising properties that may be able to suppress toxicity while maintaining the positive effects of selenium on an organism. The aim of the experiment was to determine the influence of sodium selenite and selenium nanoparticles (SeNPs) on the antioxidant status of rats. METHODS: The males of the outbreed rat strain Wistar albino were selected as a model organism. Animals were fed different forms of selenium. The control group was given a mixture without selenium addition, whereas other groups were fed a mixture containing sodium selenite, Se-49, and Se-100 SeNPs respectively. The duration of the trial was 30 days. RESULTS: Analysis of blood and liver was performed where the concentration of reduced (GSH) and oxidised (GSSG) glutathione, and total selenium content were measured. In the liver, a significant reduction in GSSG was found for all experiment groups. Blood samples showed a significant reduction in GSH and an increase in GSSG. DISCUSSION: These results show that SeNPs may be an alternative to dietary selenium for animal organisms.

• Klíčová slova
• Animal nutrition, Antioxidant, Glutathione, Rat, Selenium nanoparticles,
• Publikační typ
• časopisecké články MeSH

Interactions of silver phosphate nanoparticles (SPNPs) and selenium nanoparticles (SeNPs) with Staphylococcus aureus cultures have been studied at the cellular, molecular and protein level. Significant antibacterial effects of both SPNPs and SeNPs on S. aureus were observed. At a concentration of 300 μM, SPNPs caused 37.5% inhibition of bacterial growth and SeNPs totally inhibited bacterial growth. As these effects might have been performed due to the interactions of nanoparticles with DNA and proteins, the interaction of SPNPs or SeNPs with the amplified zntR gene was studied. The presence of nanoparticles decreased the melting temperatures of the nanoparticle complexes with the zntR gene by 23% for SeNPs and by 12% for SPNPs in comparison with the control value. The concentration of bacterial metallothionein was 87% lower in bacteria after application of SPNPs (6.3 μg mg(-1) protein) but was increased by 29% after addition of SeNPs (63 μg mg(-1) protein) compared with the S. aureus control (49 μg mg(-1) protein). Significant antimicrobial effects of the nanoparticles on bacterial growth and DNA integrity provide a promising approach to reducing the risk of bacterial infections that cannot be controlled by the usual antibiotic treatments.

• Klíčová slova
• antimicrobial effect, growth, inhibition, nanotechnology,
• MeSH
• antibakteriální látky farmakologie   MeSH
• fosfáty farmakologie   MeSH
• mikrobiální testy citlivosti MeSH
• nanočástice * MeSH
• selen farmakologie   MeSH
• sloučeniny stříbra farmakologie   MeSH
• stafylokokové infekce prevence a kontrola   MeSH
• Staphylococcus aureus účinky léků   růst a vývoj   MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• antibakteriální látky MeSH
• fosfáty MeSH
• selen MeSH
• silver phosphate MeSH Prohlížeč
• sloučeniny stříbra MeSH

Selenium is an essential trace element that is crucial for cellular antioxidant defense against reactive oxygen species (ROS). Recently, many selenium-containing compounds have exhibited a wide spectrum of biological activities that make them promising scaffolds in Medicinal Chemistry, and, in particular, in the search for novel compounds with anticancer activity. Similarly, certain tellurium-containing compounds have also exhibited substantial biological activities. Here we provide an overview of the biological activities of seleno- and tellurocompounds including chemopreventive activity, antioxidant or pro-oxidant activity, modulation of the inflammatory processes, induction of apoptosis, modulation of autophagy, inhibition of multidrug efflux pumps such as P-gp, inhibition of cancer metastasis, selective targeting of tumors and enhancement of the cytotoxic activity of chemotherapeutic drugs, as well as overcoming tumor drug resistance. A review of the chemistry of the most relevant seleno- or tellurocompounds with activity against resistant cancers is also presented, paying attention to the synthesis of these compounds and to the preparation of bioactive selenium or tellurium nanoparticles. Based on these data, the use of these seleno- and tellurocompounds is a promising approach in the development of strategies that can drive forward the search for novel therapies or adjuvants of current therapies against drug-resistant cancers.

• Klíčová slova
• Apoptosis, Autophagy, Cancer, Drug combination, Drug development, Efflux pumps, Free radicals, Inflammation, Multidrug resistance (MDR), Selenium, Tellurium,
• MeSH
• chemorezistence MeSH
• lidé MeSH
• mnohočetná léková rezistence MeSH
• nádory * farmakoterapie   MeSH
• nanočástice * MeSH
• protinádorové látky * chemie   farmakologie   terapeutické užití   MeSH
• reaktivní formy kyslíku MeSH
• selen * chemie   farmakologie   terapeutické užití   MeSH
• telur chemie   farmakologie   terapeutické užití   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• přehledy MeSH
• Názvy látek
• protinádorové látky * MeSH
• reaktivní formy kyslíku MeSH
• selen * MeSH
• telur MeSH

Previous studies of green synthesized selenium nanoparticles (SeNPs) showed their unique properties such as antibacterial activity, biocompatibility, and antioxidant properties. This study aimed to use traditional Zambian medicinal herbs (Azadirachta indica, Moringa oleifera Gliricidia sepium, Cissus quadrangularis, Aloe barbadensis, Kigelia Africana, and Bobgunnia madagascariensis) to synthesize SeNPs and examine their potential to enhance the endogenous antioxidant system of model eukaryote. For SeNP characterization, dynamic light scattering, scanning electron microscopy, Fourier transform infrared spectroscopy,and absorbance spectra were used. Their minimal inhibitory concentration was investigated on Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli) bacteria. The antioxidant potential of SeNPs was examined on Saccharomyces cerevisiae (S. cerevisiae). Cell viability, total antioxidant capacity, and activity of superoxide dismutase, catalase, and glutathione peroxidase were evaluated. SeNPs did not show antimicrobial activity against E. coli, only mild activity against S. aureus. Experimental data suggested that SeNPs didn´t inhibit Saccharomyces cerevisiae growth while plant extracts and sodium selenite had an inhibitory effect. All tested plant extracts and SeNPs resulted in a significant decrease in superoxide dismutase activity compared to the control. Catalase activity significantly increased only in treatments with plant extracts or sodium selenite alone. Glutathione peroxidase activity remained the same for all studied SeNPs and plant extracts. These findings provide evidence of a complex influence of SeNPs or plant extracts on the cellular antioxidant system in S. cerevisiae. From the point of view of overall effectiveness, Azadirachta indica, Moringa oleifera, Aloe barbadensis, and Cissus quadrangularis SeNPs are promising, green-synthetized nanoparticles for combating oxidative stress in living organisms.

• MeSH
• antiinfekční látky * farmakologie   chemie   MeSH
• antioxidancia * farmakologie   chemie   MeSH
• Escherichia coli účinky léků   MeSH
• kovové nanočástice * chemie   MeSH
• léčivé rostliny * chemie   MeSH
• mikrobiální testy citlivosti MeSH
• nanočástice * chemie   MeSH
• rostlinné extrakty chemie   farmakologie   MeSH
• Saccharomyces cerevisiae účinky léků   růst a vývoj   MeSH
• selen * chemie   farmakologie   MeSH
• Staphylococcus aureus účinky léků   MeSH
• superoxiddismutasa metabolismus   MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• antiinfekční látky * MeSH
• antioxidancia * MeSH
• rostlinné extrakty MeSH
• selen * MeSH
• superoxiddismutasa MeSH

In this study, we tested the ability of lactobacilli and bifidobacteria strains to accumulate and biotransform sodium selenite into various selenium species, including selenium nanoparticles (SeNPs). Selenium tolerance and cytotoxicity of selenized strains towards human adenocarcinoma Caco-2 and HT29 cells were determined for all tested strains. Furthermore, the influence of selenium enrichment on the antioxidant activity of selenized strains and hydrophobicity of the bacterial cell surfaces were evaluated. Both hydrophobicity and antioxidant activity increased significantly in the selenized L. paracasei strain and decreased significantly in the selenized L. helveticus strain. The concentrations of 5 and 10 mg/L Na2SeO3 in the growth media were safer for Caco-2 and HT29 cell growth than higher concentrations. At higher concentrations (30, 50, and 100 mg/L), the cell viability was reduced. All the tested strains showed differences in antioxidant potential and hydrophobicity after selenium enrichment. In addition to selenocystine ​​and selenomethionine, the tested bacterial strains produced significant amounts of SeNPs. Our results show that the tested bacterial strains can accumulate and biotransform inorganic selenium, which allows them to become a potential source of selenium.

• Klíčová slova
• Bioaccumulation, Cytotoxicity, Functional foods, Nanoparticles, Selenium,
• MeSH
• antioxidancia MeSH
• Caco-2 buňky MeSH
• Lactobacillus metabolismus   MeSH
• lidé MeSH
• potravní doplňky MeSH
• selen * metabolismus   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• antioxidancia MeSH
• selen * MeSH

This paper reviews the current understanding of the toxicity of selenium (Se) to terrestrial mammalian and aquatic organisms. Adverse biological effects occur in the case of Se deficiencies, associated with this element having essential biological functions and a narrow window between essentiality and toxicity. Several inorganic species of Se (-2, 0, +4, and +6) and organic species (monomethylated and dimethylated) have been reported in aquatic systems. The toxicity of Se in any given sample depends not only on its speciation and concentration, but also on the concomitant presence of other compounds that may have synergistic or antagonistic effects, affecting the target organism as well, usually spanning 2 or 3 orders of magnitude for inorganic Se species. In aquatic ecosystems, indirect toxic effects, linked to the trophic transfer of excess Se, are usually of much more concern than direct Se toxicity. Studies on the toxicity of selenium nanoparticles indicate the greater toxicity of chemically generated selenium nanoparticles relative to selenium oxyanions for fish and fish embryos while oxyanions of selenium have been found to be more highly toxic to rats as compared to nano-Se. Studies on polymer coated Cd/Se quantum dots suggest significant differences in toxicity of weathered vs. non-weathered QD's as well as a significant role for cadmium with respect to toxicity.

• Klíčová slova
• Biological selenium, Metals, Nanoparticles, Organisms, Quantum dots, Toxicity,
• MeSH
• ekosystém MeSH
• krysa rodu Rattus MeSH
• kvantové tečky toxicita   MeSH
• látky znečišťující životní prostředí toxicita   MeSH
• lidé MeSH
• organoselenové sloučeniny toxicita   MeSH
• skot MeSH
• sloučeniny kadmia toxicita   MeSH
• sloučeniny selenu toxicita   MeSH
• synergismus léků MeSH
• vodní organismy účinky léků   růst a vývoj   MeSH
• zvířata MeSH
• Check Tag
• krysa rodu Rattus MeSH
• lidé MeSH
• skot MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• přehledy MeSH
• Názvy látek
• cadmium selenide MeSH Prohlížeč
• látky znečišťující životní prostředí MeSH
• organoselenové sloučeniny MeSH
• sloučeniny kadmia MeSH
• sloučeniny selenu MeSH

In a biological system, nanoparticles (NPs) may interact with biomolecules. Specifically, the adsorption of proteins on the nanoparticle surface may influence both the nanoparticles' and proteins' overall bio-reactivity. Nevertheless, our knowledge of the biocompatibility and risk of exposure to nanomaterials is limited. Here, in vitro and ex ovo biocompatibility of naturally based crosslinked freeze-dried 3D porous collagen/chitosan scaffolds, modified with thermostable fibroblast growth factor 2 (FGF2-STAB®), to enhance healing and selenium nanoparticles (SeNPs) to provide antibacterial activity, were evaluated. Biocompatibility and cytotoxicity were tested in vitro using normal human dermal fibroblasts (NHDF) with scaffolds and SeNPs and FGF2-STAB® solutions. Metabolic activity assays indicated an antagonistic effect of SeNPs and FGF2-STAB® at high concentrations of SeNPs. The half-maximal inhibitory concentration (IC50) of SeNPs for NHDF was 18.9 µg/ml and IC80 was 5.6 µg/ml. The angiogenic properties of the scaffolds were monitored ex ovo using a chick chorioallantoic membrane (CAM) assay and the cytotoxicity of SeNPs over IC80 value was confirmed. Furthermore, the positive effect of FGF2-STAB® at very low concentrations (0.01 µg/ml) on NHDF metabolic activity was observed. Based on detailed in vitro testing, the optimal concentrations of additives in the scaffolds were determined, specifically 1 µg/ml of FGF2-STAB® and 1 µg/ml of SeNPs. The scaffolds were further subjected to antimicrobial tests, where an increase in selenium concentration in the collagen/chitosan scaffolds increased the antibacterial activity. This work highlights the antimicrobial ability and biocompatibility of newly developed crosslinked collagen/chitosan scaffolds involving FGF2-STAB® and SeNPs. Moreover, we suggest that these sponges could be used as scaffolds for growing cells in systems with low mechanical loading in tissue engineering, especially in dermis replacement, where neovascularization is a crucial parameter for successful skin regeneration. Due to their antimicrobial properties, these scaffolds are also highly promising for tissue replacement requiring the prevention of infection.

• Klíčová slova
• 3D porous scaffold, Chitosan, Collagen, Fibroblast growth factor 2, Selenium nanoparticles,
• MeSH
• antibakteriální látky MeSH
• biokompatibilní materiály farmakologie   MeSH
• buněčné linie MeSH
• chitosan farmakologie   MeSH
• fibroblastový růstový faktor 2 farmakologie   MeSH
• fibroblasty účinky léků   MeSH
• hojení ran MeSH
• kolagen farmakologie   MeSH
• lidé MeSH
• nanočástice chemie   terapeutické užití   MeSH
• poréznost MeSH
• selen chemie   farmakologie   MeSH
• testování materiálů MeSH
• tkáňové inženýrství metody   MeSH
• tkáňové podpůrné struktury * MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• antibakteriální látky MeSH
• biokompatibilní materiály MeSH
• chitosan MeSH
• fibroblastový růstový faktor 2 MeSH
• kolagen MeSH
• selen MeSH

Parylene-based implants or coatings introduce surfaces suffering from bacteria colonization. Here, we synthesized polyvinylpyrrolidone-stabilized selenium nanoparticles (SeNPs) as the antibacterial agent, and various approaches are studied for their reproducible adsorption, and thus the modification of parylene-C-coated glass substrate. The nanoparticle deposition process is optimized in the nanoparticle concentration to obtain evenly distributed NPs on the flat parylene-C surface. Moreover, the array of parylene-C micropillars is fabricated by the plasma etching of parylene-C on a silicon wafer, and the surface is modified with SeNPs. All designed surfaces are tested against two bacterial pathogens, Escherichia coli (Gram-negative) and Staphylococcus aureus (Gram-positive). The results show no antibacterial effect toward S. aureus, while some bacteriostatic effect is observed for E. coli on the flat and microstructured parylene. However, SeNPs did not enhance the antibacterial effect against both bacteria. Additionally, all designed surfaces show cytotoxic effects toward mesenchymal stem cells at high SeNP deposition. These results provide valuable information about the potential antibacterial treatment of widely used parylene-C in biomedicine.

• Klíčová slova
• antimicrobial, biocompatibility, micropillars, parylene-C, selenium nanoparticles,
• Publikační typ
• časopisecké články MeSH