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1.
Int J Food Microbiol ; 344: 109116, 2021 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-33676332

RESUMO

Staphylococcus aureus is among the most common zoonotic pathogens originating from animals consumed as food, especially raw chicken meat (RCM). As far as we know, this might be the first report that explores the efficacy of metal oxide nanoparticles (MONPs), such as zinc peroxide nanoparticles (ZnO2-NPs), zinc oxide nanoparticles (ZnO-NPs), and titanium dioxide nanoparticles (TiO2-NPs) against multidrug resistant (MDR) and/or pandrug resistant (PDR) S. aureus strains with a strong biofilm-producing ability isolated from RCM and giblets. The overall prevalence of coagulase-positive staphylococci was 21%, with a contamination level range between 102 and 104 CFU/g. The incidence of virulence genes See (21/36), pvl (16/36), clfA (15/36), sec (12/36), tst (12/36), and sea (11/36) among S. aureus strains were relatively higher those of seb, sed, fnbA, and fnbB. For antimicrobial resistance gene distribution, most strains harbored the blaZ gene (25/36), aacA-aphD gene (24/36), mecA gene (22/36), vanA gene (20/36), and apmA gene (20/36) confirmed the prevalence of MDR among S. aureus of RCM products. However, cfr (11/36), spc (9/36), and aadE (7/36) showed a relatively lower existence. The data of antibiogram resistance profiles was noticeably heterogeneous (25 patterns) with 32 MDR and four PDR S. aureus strains. All tested strains had a very high MAR index value (>0.2) except the P11 pattern (GEN, MXF, PMB), which showed a MAR index of 0.19. Among the strong biofilm-producing ability (BPA), 14 (70%) strains were isolated from wet markets, while only six strong BPA strains were isolated from supermarkets. The mean values of BPA ranged from 2.613 ± 0.04 to 11.013 ± 0.05. Clearly, ZnO2-NPs show significant inhibitory activity against S. aureus strains compared with those produced by the action of ZnO-NPs and TiO2-NPs. The results of anti-inflammatory activity suggest ZnO2-NPs as a lead compound for designing an alternative antimicrobial agent against drug-resistant and strong biofilm-producing S. aureus isolates from retail RCM and giblets.


Assuntos
Antibacterianos/farmacologia , Contaminação de Alimentos/prevenção & controle , Staphylococcus aureus/crescimento & desenvolvimento , Titânio/farmacologia , Óxido de Zinco/farmacologia , Animais , Biofilmes/efeitos dos fármacos , Biofilmes/crescimento & desenvolvimento , Galinhas/microbiologia , Farmacorresistência Bacteriana Múltipla/genética , Contaminação de Alimentos/análise , Microbiologia de Alimentos , Carne/microbiologia , Nanopartículas Metálicas , Testes de Sensibilidade Microbiana , Infecções Estafilocócicas/epidemiologia , Infecções Estafilocócicas/prevenção & controle , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/isolamento & purificação , Virulência/genética
2.
Plant Physiol Biochem ; 160: 341-351, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33548801

RESUMO

The present study is the first attempt to demonstrate the beneficiary effects of seed priming with zinc oxide nanoparticles (ZnO NPs) in wheat cultivar H-I 1544. Wheat seeds primed with ZnO NPs (10 mg/L) showed a significant positive influence on seed germination performance and vigour index as compared to unprimed (control) and hydroprimed seeds. Furthermore, nanopriming also enhanced seed water uptake resulting in enhanced α-amylase activity. Content of photosynthetic pigments in nanoprimed plants (chlorophyll a, chlorophyll b and total chlorophyll content) was significantly enhanced. Chlorophyll a fluorescence measurements were performed 30 days after cultivation of nanoprimed seeds to investigate the effect of nanopriming on plant photosynthetic performance. Results suggested that ZnO NPs affects the overall primary photochemistry by enhancing the performance of water splitting complex at donor side of PSII (Fv/Fo). The numbers of active reaction centres (RC) per chlorophyll molecule were increased in nanoprimed plants followed by increase in the absorption (ABS), efficiency of excitation energy trapping (TR) and electron transport (ET) from active reaction centres. The impact of nanopriming on oxidative status of plants was also studied by measuring the activity enzymes like peroxidase (POD), catalase (CAT), superoxide dismutase (SOD) and degree of lipid peroxidation. A prominent decrease in the activity of these enzymes was observed which may be attributed to low reactive oxygen species (ROS) levels in nanoprimed plants as compared to control. This is the first report showing ZnO NPs as a promising seed priming agent to improve germination as well as photosynthetic performance of wheat seeds.


Assuntos
Germinação/efeitos dos fármacos , Nanopartículas , Fotossíntese/efeitos dos fármacos , Triticum/fisiologia , Óxido de Zinco , Clorofila , Triticum/efeitos dos fármacos , Óxido de Zinco/farmacologia
3.
Arch Oral Biol ; 122: 105031, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33412420

RESUMO

OBJECTIVE: This study evaluates the antibacterial activity against mono and multispecies bacterial models and the cytotoxic effects of zinc oxide and copper nanoparticles(ZnO-NPs/Cu-NPs) in cell cultures of human gingival fibroblasts(HGFs). DESIGN: The antibacterial activities of ZnO-NPs and Cu-NPs against 4 bacteria species were tested according to their minimum inhibitory concentrations(MICs) and against mature multispecies anaerobic model by spectral confocal laser scanning microscopy. The viabilities and cytotoxic effects of ZnO-NPs and Cu-NPs to HGFs cell cultures were tested by MTT, LDH assays, production of ROS, and the activation of caspase-3. The results were analyzed using one-way ANOVA followed by Tukey tests, considering p < 0.05 as statistically significant. RESULTS: For all strains, MICs of ZnO-NPs and Cu-NPs were in the range of 78.3 µg/mL-3906 µg/mL and 125 µg/mL-625 ug/mL, respectively. In a multispecies model, a significant decrease in the total biomass volume(µ3) was observed in response to exposure to 125 µg/mL of each NPs for which there was bactericidal activity. Significant differences were found between the volumes of viable and nonviable biomass exposed to nanostructures with Cu-NPs compared to ZnO-NPs. Both NPs induced mitochondrial dose-dependent cytotoxicity, ZnO-NPs increases LDH release and intracellular ROS generation. Cu-NPs at a concentration of 50 µg/mL induced production of cleaved caspase-3, activating the apoptotic pathway early and at low doses. CONCLUSIONS: After 24 h, ZnO-NPs are biocompatible between 78-100 µg/mL and Cu-NPs below 50 µg/mL. Antibacterial activity in a monospecies model is strain dependent, and in a multispecies model was a lower doses after 10 min of exposure.


Assuntos
Antibacterianos/farmacologia , Cobre/farmacologia , Implantes Dentários , Desinfetantes/farmacologia , Nanopartículas , Óxido de Zinco/farmacologia , Antibacterianos/toxicidade , Células Cultivadas , Cobre/toxicidade , Desinfetantes/toxicidade , Fibroblastos/citologia , Gengiva/citologia , Humanos , Testes de Sensibilidade Microbiana , Nanopartículas/toxicidade , Óxido de Zinco/toxicidade
4.
Int J Nanomedicine ; 16: 89-104, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33447029

RESUMO

Background: Therapeutic selectivity and drug resistance are critical issues in cancer therapy. Currently, zinc oxide nanoparticles (ZnO NPs) hold considerable promise to tackle this problem due to their tunable physicochemical properties. This work was designed to prepare SnO2-doped ZnO NPs/reduced graphene oxide nanocomposites (SnO2-ZnO/rGO NCs) with enhanced anticancer activity and better biocompatibility than those of pure ZnO NPs. Materials and Methods: Pure ZnO NPs, SnO2-doped ZnO (SnO2-ZnO) NPs, and SnO2-ZnO/rGO NCs were prepared via a facile hydrothermal method. Prepared samples were characterized by field emission transmission electron microscopy (FETEM), energy dispersive spectroscopy (EDS), field emission scanning electron microscopy (FESEM), X-ray diffraction (XRD), ultraviolet-visible (UV-VIS) spectrometer, and dynamic light scattering (DLS) techniques. Selectivity and anticancer activity of prepared samples were assessed in human breast cancer (MCF-7) and human normal breast epithelial (MCF10A) cells. Possible mechanisms of anticancer activity of prepared samples were explored through oxidative stress pathway. Results: XRD spectra of SnO2-ZnO/rGO NCs confirmed the formation of single-phase of hexagonal wurtzite ZnO. High resolution TEM and SEM mapping showed homogenous distribution of SnO2 and rGO in ZnO NPs with high quality lattice fringes without any distortion. Band gap energy of SnO2-ZnO/rGO NCs was lower compared to SnO2-ZnO NPs and pure ZnO NPs. The SnO2-ZnO/rGO NCs exhibited significantly higher anticancer activity against MCF-7 cancer cells than those of SnO2-ZnO NPs and ZnO NPs. The SnO2-ZnO/rGO NCs induced apoptotic response through the upregulation of caspase-3 gene and depletion of mitochondrial membrane potential. Mechanistic study indicated that SnO2-ZnO/rGO NCs kill cancer cells through oxidative stress pathway. Moreover, biocompatibility of SnO2-ZnO/rGO NCs was also higher against normal breast epithelial (MCF10A cells) in comparison to SnO2-ZnO NPs and ZnO NPs. Conclusion: SnO2-ZnO/rGO NCs showed enhanced anticancer activity and better biocompatibility than SnO2-ZnO NPs and pure ZnO NPs. This work suggested a new approach to improve the selectivity and anticancer activity of ZnO NPs. Studies on antitumor activity of SnO2-ZnO/rGO NCs in animal models are further warranted.


Assuntos
Antineoplásicos/farmacologia , Grafite/síntese química , Grafite/farmacologia , Nanocompostos/química , Estresse Oxidativo , Compostos de Estanho/síntese química , Óxido de Zinco/síntese química , Óxido de Zinco/farmacologia , Apoptose/efeitos dos fármacos , Difusão Dinâmica da Luz , Grafite/química , Humanos , Células MCF-7 , Nanocompostos/ultraestrutura , Nanopartículas/química , Fenômenos Ópticos , Estresse Oxidativo/efeitos dos fármacos , Espectrometria por Raios X , Compostos de Estanho/farmacologia , Difração de Raios X , Óxido de Zinco/química
5.
Food Chem ; 334: 127605, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-32738726

RESUMO

Chitosan (Ch) and zinc oxide nanoparticles loaded gallic-acid films, (Ch-ZnO@gal) have been prepared aiming for their exploitation as environmentally benign food packaging material. The chitosan films with varying quantities of zinc oxide nanoparticles loaded gallic-acid (ZnO@gal) content were synthesized in order to evaluate the effect of ZnO@gal on their optimum mechanical and biological potential. The characteristic results have shown that the incorporation of ZnO@gal into chitosan films remarkably enhanced the desired mechanical property of the chitosan films. Other noticeable physical properties such as oxygen and water vapor permeability (WVP), swelling, water solubility and UV-vis light transmittance have also been found to improve positively. SEM analysis of the films indicates a good material compatibility between chitosan and ZnO@gal matrices. Ch-ZnO@gal films possess significant antibacterial potential and strong antioxidant behavior compared to pristine chitosan. The overall results suggested that the prepared biocomposite chitosan films may be considered for active food packaging applications.


Assuntos
Quitosana/química , Embalagem de Alimentos/métodos , Ácido Gálico/química , Nanopartículas/química , Óxido de Zinco/química , Antibacterianos/química , Antioxidantes/química , Bacillus subtilis/efeitos dos fármacos , Materiais Biocompatíveis/química , Escherichia coli/efeitos dos fármacos , Embalagem de Alimentos/instrumentação , Permeabilidade , Solubilidade , Vapor , Resistência à Tração , Raios Ultravioleta , Óxido de Zinco/farmacologia
6.
PLoS One ; 15(12): e0243802, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33326476

RESUMO

Zinc oxide (ZnO) NP is considered as a nanoscale chemotherapeutic. Thus, the drug delivery of this inorganic NP is of considerable importance. Ras mutations are common in cancer and the activation of this signaling pathway is a hallmark in carcinoma, melanoma and many other aggressive malignancies. Thus, here we examined the binding and delivery of Ras binding domain (RBD), a model cancer-relevant protein and effector of Ras by ZnO NP. Shifts in zeta potential in water, PBS, DMEM and DMEM supplemented with FBS supported NP interaction to RBD. Fluorescence quenching of the NP was concentration-dependent for RBD, Stern-Volmer analysis of this data was used to estimate binding strength which was significant for ZnO-RBD (Kd < 10-5). ZnO NP interaction to RBD was further confirmed by pull-down assay demonstrated by SDS-PAGE analysis. The ability of ZnO NP to inhibit 3-D tumor spheroid was demonstrated in HeLa cell spheroids-the ZnO NP breaking apart these structures revealing a significant (>50%) zone of killing as shown by light and fluorescence microscopy after intra-vital staining. ZnO 100 nm was superior to ZnO 14 nm in terms of anticancer activity. When bound to ZnO NP, the anticancer activity of RBD was enhanced. These data indicate the potential diagnostic application or therapeutic activity of RBD-NP complexes in vivo which demands further investigation.


Assuntos
Antineoplásicos/metabolismo , Antineoplásicos/farmacologia , Nanopartículas , Óxido de Zinco/metabolismo , Óxido de Zinco/farmacologia , Proteínas ras/metabolismo , Animais , Antineoplásicos/química , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Camundongos , Ligação Proteica , Óxido de Zinco/química , Proteínas ras/química
7.
Int J Nanomedicine ; 15: 7901-7921, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33116508

RESUMO

Introduction: Zinc oxide nanoparticles (ZnO NPs) have recently attracted attention as potential anti-cancer agents. To the best of our knowledge, the toxicity of ZnO NPs against human chronic myeloid leukemia cells (K562 cell line) has not been studied using transcriptomics approach. Objective: The goals of this study were to evaluate the capability of ZnO NPs to induce apoptosis in human chronic myeloid leukemia cells (K562 cells) and to investigate the putative mechanisms of action. Methods: We used viability assay and flowcytometry coupled with Annexin V-FITC and propidium iodide to investigate the toxicity of ZnO NPs on K562 cells and normal peripheral blood mononuclear cells. Next we utilized a DNA microarray-based transcriptomics approach to characterize the ZnO NPs-induced changes in the transcriptome of K562 cells. Results: ZnO NPs exerted a selective toxicity (mainly by apoptosis) on the leukemic cells (p≤0.005) and altered their transcriptome; 429 differentially expressed genes (DEGs) with fold change (FC)≥4 and p≤0.008 with corrected p≤0.05 were identified in K562 cells post treatment with ZnO NPs. The over-expressed genes were implicated in "response to zinc", "response to toxic substance" and "negative regulation of growth" (corrected p≤0.05). In contrast, the repressed genes positively regulated "cell proliferation", "cell migration", "cell adhesion", "receptor signaling pathway via JAK-STAT" and "phosphatidylinositol 3-kinase signaling" (corrected p≤0.05). Lowering the FC to ≥1.5 with p≤0.05 and corrected p≤0.1 showed that ZnO NPs over-expressed the anti-oxidant defense system, drove K562 cells to undergo mitochondrial-dependent apoptosis, and targeted NF-κB pathway. Conclusion: Taken together, our findings support the earlier studies that reported anti-cancer activity of ZnO NPs and revealed possible molecular mechanisms employed by ZnO NPs to induce apoptosis in K562 cells.


Assuntos
Antineoplásicos/química , Antineoplásicos/farmacologia , Perfilação da Expressão Gênica , Leucemia Mielogênica Crônica BCR-ABL Positiva/patologia , Nanopartículas , Óxido de Zinco/química , Óxido de Zinco/farmacologia , Apoptose/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Humanos , Células K562 , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos
8.
Int J Nanomedicine ; 15: 8045-8057, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33116517

RESUMO

Purpose: To study the cytotoxic evaluation, antimicrobial and confocal analysis of zinc oxide nanoparticles (ZnO NPs) obtained from a novel plant product fennel (Foeniculum vulgare Mill.) seed extract (FSE). Methods: ZnO NPs were analyzed using UV-Vis spectroscopy, XRD, FTIR, TEM and EDX techniques. The MTT cell cytotoxicity assay measured the proliferation and survival of MCF-7 cells treated at different concentrations of FSE-derived ZnO NPs. The antimicrobial activity towards pathogenic bacteria and yeast strains was investigated. Results: The UV-Vis spectra showed two peaks at 438 nm and 446 nm, confirming nanoparticle formation. The SEM morphology results showed porous ranging from 23-51 nm. The antitumor activity value (IC50) was at 50 µg/mL and 100 µg/mL. Besides, morphological changes of MCF-7, cells treated at different concentrations of FSE of ZnO NPs were observed in cell cultures transfected with a transient pCMV6-XL4-GFP-expressing vector containing C-terminal domain GFP-tagged proteins, which resulted in an apoptotic effect. Antimicrobial IZ ranged up No Inhibition to 18.00 ± 0.4. The IZ revealed at the highest concentration was E. faecium VRE and yeast Cryptococcus sp. (18.00 ± 0.4. mm), followed by S. aureus (17.00 ± 0.2 mm) and P. aeruginosa and the yeast C. parapsilosis (16 ± 0.4 mm). The IZ was equal to that caused by the nystatin to Cryptococcus sp., which was significantly highest than ampicillin treatments of S. aureus, P. aeruginosa, C. albicans, and C. parapsilosis. The MIC value of the FSE-derived ZnO NPs tested against E.faecium and C.albicans was 6.00 µg/mL (E. faecium and C. albicans). It was 32.00 µg/mL (S. aureus, S. typhimurium and Cryptococcus sp.), 64.00 µg/mL (P. aeruginosa), and 128 µg/mL (C. parapsilosis). Conclusion: As far as it is to our knowledge, this study established, for the first time, the biological activities of biosynthesized ZnO NPs from FSE and their synergistic therapeutic potential.


Assuntos
Foeniculum/química , Química Verde/métodos , Nanopartículas Metálicas/química , Extratos Vegetais/química , Sementes/química , Óxido de Zinco/farmacologia , Antibacterianos/farmacologia , Morte Celular/efeitos dos fármacos , Forma Celular/efeitos dos fármacos , Humanos , Células MCF-7 , Nanopartículas Metálicas/ultraestrutura , Testes de Sensibilidade Microbiana , Staphylococcus aureus/efeitos dos fármacos , Difração de Raios X
9.
J Biomed Nanotechnol ; 16(4): 456-466, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-32970978

RESUMO

Among different forms of metallic nanoparticles (NPs), zinc oxide (ZnO) NPs with a very special bandgap of 3.37 eV and considerable binding energy of excitation (60 meV at room temperature), have been classified as high-tech nanoparticles. This study aimed to synthesize ZnO NPs using the extract from Salvia hispanica leaves. The synthesized nanoparticles were fully characterized and the photocatalytic activity was evaluated through the degradation of methylene blue. Additionally, the potential in vitro biological activities of such ZnO NPs in terms of their antibacterial activity were determined, as well as their antioxidant (30 minutes), antiviral (48 hours) and mammalian cell viability properties (48 and 72 hours). This study is the first investigation into the synthesis of such green ZnO NPs mediated by this plant extract, in which both photocatalytic and biomedical properties were found to be promising. The IC50 values for the antibacterial activities were found to be around 17.4 µg mL-1 and 28.5 µg mL-1 for S. aureus and E. coli, respectively, and the antioxidant activity was comparable with the standard BHT. However, the H1N1 inhibition rate using the present green ZnO NPs was lower than oseltamivir (up to about 40% for ZnO NPs and above 90% for oseltamivir) which was expected since it is a drug, but was higher than many synthetic nanoparticles reported in the literature. In addition, the mammalian cell viability assay showed a higher than 80% cellular viability in the presence of 5, 10 and 20 µg mL-1 nanoparticles, and showed a higher than 50% cellular viability in the presence of 50 and 75 µg mL-1 nanoparticles. In this manner, this study showed that these green ZnO NPs should be studied for a wide range of medical applications.


Assuntos
Vírus da Influenza A Subtipo H1N1 , Nanopartículas Metálicas , Salvia , Animais , Antibacterianos/farmacologia , Antioxidantes/farmacologia , Sobrevivência Celular , Escherichia coli , Química Verde , Mamíferos , Testes de Sensibilidade Microbiana , Staphylococcus aureus , Difração de Raios X , Óxido de Zinco/farmacologia
10.
Dental Press J Orthod ; 25(4): 51-58, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32965387

RESUMO

OBJECTIVE: To investigate the effect of ZnO nanocoating on mechanical properties of NiTi orthodontic wires and antibacterial activity. METHODS: 0.016 x 0.022-in NiTi orthodontic wires were coated with ZnO nanoparticles using an electrochemical deposition method with three electrodes system in 0.1M Zn(NO3)2. Mechanical properties and frictional resistance of the coated wires were investigated using an universal testing machine. Antibacterial effect of ZnO coating was also investigated. RESULTS: A stable adhered ZnO nanocoating on NiTi wires was obtained. The coated wires have a significant antibacterial activity against S. aureus, S. pyogens and E. coli, and a reduction of frictional forces by 34%. CONCLUSION: ZnO nanocoating may improve the antibacterial effects of NiTi wires and reduce the frictional resistance. Coating may be implanted in orthodontic practice for faster and safer treatment.


Assuntos
Óxido de Zinco/farmacologia , Antibacterianos/farmacologia , Ligas Dentárias , Escherichia coli , Teste de Materiais , Níquel , Fios Ortodônticos , Staphylococcus aureus , Propriedades de Superfície , Titânio/farmacologia , Zinco
11.
Int J Food Microbiol ; 334: 108838, 2020 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-32896745

RESUMO

White brined cheese may serve as an ideal medium for the growth of foodborne pathogens including E. coli O157:H7. The objectives of this study were i) to evaluate the inhibitory effects of zinc oxide (ZnO) nanoparticles against E. coli O157:H7 at 10 or 37 °C using broth dilution; ii) to address the post-process contamination of white brined cheese with E. coli O157:H7 by using chitosan coating with or without ZnO nanoparticles during storage for 28 d at 4 and 10 °C; and iii) to study the physicochemical characteristics of chitosan coating containing ZnO nanoparticles. ZnO nanoparticles at ≥0.0125% inhibited the growth of three E. coli O157:H7 strains at both 37 and 10 °C. The chitosan coating with or without ZnO nanoparticles significantly reduced the initial numbers of E. coli O157:H7 in white brined cheese by 2.5 and 2.8 log CFU/g, respectively, when stored at 4 °C or by 1.9 and 2.1 log CFU/g, respectively, when stored at 10 °C. The chitosan-ZnO nanoparticle coating was not significantly different (p > 0.05) but was slightly better than chitosan alone as an active, smart packaging material in food applications.


Assuntos
Anti-Infecciosos/farmacologia , Queijo/microbiologia , Quitosana/química , Escherichia coli O157/efeitos dos fármacos , Óxido de Zinco/química , Anti-Infecciosos/química , Quitosana/farmacologia , Contagem de Colônia Microbiana , Escherichia coli O157/crescimento & desenvolvimento , Microbiologia de Alimentos , Armazenamento de Alimentos , Nanopartículas/química , Sais/análise , Temperatura , Óxido de Zinco/farmacologia
12.
Int J Nanomedicine ; 15: 6247-6262, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32903812

RESUMO

Prosthesis-associated infections and aseptic loosening are major causes of implant failure. There is an urgent need to improve the antibacterial ability and osseointegration of orthopedic implants. Zinc oxide nanoparticles (ZnO-NPs) are a common type of zinc-containing metal oxide nanoparticles that have been widely studied in many fields, such as food packaging, pollution treatment, and biomedicine. The ZnO-NPs have low toxicity and good biological functions, as well as antibacterial, anticancer, and osteogenic capabilities. Furthermore, ZnO-NPs can be easily obtained through various methods. Among them, green preparation methods can improve the bioactivity of ZnO-NPs and strengthen their potential application in the biological field. This review discusses the antibacterial abilities of ZnO-NPs, including mechanisms and influencing factors. The toxicity and shortcomings of anticancer applications are summarized. Furthermore, osteogenic mechanisms and synergy with other materials are introduced. Green preparation methods are also briefly reviewed.


Assuntos
Antibacterianos/farmacologia , Nanopartículas Metálicas/química , Osteogênese/efeitos dos fármacos , Óxido de Zinco/farmacologia , Animais , Antibacterianos/química , Antineoplásicos/efeitos adversos , Antineoplásicos/química , Antineoplásicos/farmacologia , Condrogênese/efeitos dos fármacos , Química Verde , Humanos , Nanopartículas Metálicas/efeitos adversos , Nanopartículas Metálicas/uso terapêutico , Osteogênese/fisiologia , Próteses e Implantes , Óxido de Zinco/efeitos adversos , Óxido de Zinco/toxicidade
13.
PLoS One ; 15(9): e0232729, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32915786

RESUMO

Zinc ions (Zn2+) are important messenger molecules involved in various physiological functions. To maintain the homeostasis of cytosolic Zn2+ concentration ([Zn2+]c), Zrt/Irt-related proteins (ZIPs) and Zn2+ transporters (ZnTs) are the two families of proteins responsible for decreasing and increasing the [Zn2+]c, respectively, by fluxing Zn2+ across the membranes of the cell and intracellular compartments in opposite directions. Most studies focus on the cytotoxicity incurred by a high concentration of [Zn2+]c and less investigate the [Zn2+]c at physiological levels. Zinc oxide-nanoparticle (ZnO-NP) is blood brain barrier-permeable and elevates the [Zn2+]c to different levels according to the concentrations of ZnO-NP applied. In this study, we mildly elevated the [Zn2+]c by ZnO-NP at concentrations below 1 µg/ml, which had little cytotoxicity, in cultured human neuroblastoma SH-SY5Y cells and characterized the importance of Zn2+ transporters in 6-hydroxy dopamine (6-OHDA)-induced cell death. The results show that ZnO-NP at low concentrations elevated the [Zn2+]c transiently in 6 hr, then declined gradually to a basal level in 24 hr. Knocking down the expression levels of ZnT1 (located mostly at the plasma membrane) and ZIP8 (present in endosomes and lysosomes) increased and decreased the ZnO-NP-induced elevation of [Zn2+]c, respectively. ZnO-NP treatment reduced the basal levels of reactive oxygen species and Bax/Bcl-2 mRNA ratios; in addition, ZnO-NP decreased the 6-OHDA-induced ROS production, p53 expression, and cell death. These results show that ZnO-NP-induced mild elevation in [Zn2+]c activates beneficial effects in reducing the 6-OHDA-induced cytotoxic effects. Therefore, brain-delivery of ZnO-NP can be regarded as a potential therapy for neurodegenerative diseases.


Assuntos
Proteínas de Transporte de Cátions/metabolismo , Nanopartículas Metálicas , Óxido de Zinco/farmacologia , Zinco/metabolismo , Apoptose/efeitos dos fármacos , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular , Expressão Gênica/efeitos dos fármacos , Humanos , Oxidopamina/metabolismo , Espécies Reativas de Oxigênio/metabolismo
14.
Int J Nanomedicine ; 15: 4755-4762, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32753864

RESUMO

Aim: This study was conducted to evaluate the effects of three nanoparticle solutions used as dentin pretreatments on the microshear bond strength (µSBS) of a conventional glass ionomer cement (GIC) to dentin. Materials and Methods: Ninety intact human molars were used after sectioning their occlusal surfaces to expose flat dentin surfaces. The specimens were randomly assigned to nine groups (n = 10). Group A was the control group (without using the cavity disinfectant). In groups B, C, D, and E, the prepared dentin surfaces were treated with 1 cc 2% chlorhexidine (CHX), 0.1% silver nanoparticle (SNP), 0.1% titanium dioxide nanoparticle (TNP), and 0.1% zinc oxide nanoparticle (ZNP) solutions for 1 minute, respectively, before applying the conditioner. CHX, SNPs, TNPs, and ZNPs were applied for 1 minute after applying the conditioner in groups F, G, H, and I, respectively. The specimens were restored with a conventional GIC and underwent µSBS testing after 24 hours. The data were analyzed using the one-way analysis of variance and Tukey's test (p=0.05). Results: The applications of the nanoparticles (SNP, TNP, and ZNP) after the conditioner were associated with significantly greater µSBS values compared to that of the control group (p values < 0.05). Significantly higher µSBS values were observed when TNP or ZNP was applied after the conditioner compared to their applications before the conditioner (p values < 0.05). The highest µSBS values were observed when TNP was applied after the conditioner. Conclusion: Dentin pretreatment with the nanoparticles after applying the conditioner enhanced the bond strength of the GIC to dentin compared with the control group. The best results were obtained for the TNPs applied after the conditioner.


Assuntos
Colagem Dentária , Dentina/efeitos dos fármacos , Cimentos de Ionômeros de Vidro/farmacologia , Nanopartículas Metálicas/química , Prata/farmacologia , Titânio/farmacologia , Óxido de Zinco/farmacologia , Clorexidina/farmacologia , Cimentos de Ionômeros de Vidro/química , Humanos , Teste de Materiais , Propriedades de Superfície
15.
PLoS One ; 15(7): e0230464, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32645102

RESUMO

The current study focuses on the usage of bio synthesized zinc oxide nanoparticles to increase the tissue culture efficiency of important forage grass Panicum virgatum. Zinc being a micronutrient enhanced the callogenesis and regeneration efficiency of Panicum virgatum at different concentrations. Here, we synthesized zinc oxide nanoparticles through Cymbopogon citratus leaves extract to evaluate the effect of zinc oxide nanoparticles on plant regeneration ability in switchgrass. X-ray diffraction (XRD) and attenuated total reflectance-Fourier transform infrared (ATR-FTIR) validate phase purity of green synthesize Zinc oxide nanoparticles whereas, electron microscopy (SEM) has illustrated the average size of particle 50±4 nm with hexagonal rod like shape. Energy dispersive spectroscopy X-ray (EDS) depicted major peaks of Zn (92.68%) while minor peaks refer to Oxygen (7.32%). ZnO-NPs demonstrated the incredibly promising results against callogenesis. Biosynthesized ZnO-NPs at optimum concentration showed very promising effect on plant regeneration ability. Both the explants, seeds and nodes showed dose dependent response and upon high doses exceeding 40 mg/L the results were recorded negative, whereas at 30 mg/L both explants demonstrated 70% and 76% regeneration frequency. The results conclude that ZnO-NPs enhance the plant growth and development and tailored the nutritive properties at nano-scale. Furthermore, eco-friendly approach of ZnO-NPs synthesis is strongly believed to improve in vitro regeneration frequencies in several other monocot plants.


Assuntos
Nanopartículas Metálicas , Panicum/efeitos dos fármacos , Panicum/crescimento & desenvolvimento , Técnicas de Cultura de Tecidos , Óxido de Zinco/farmacologia , Cymbopogon , Nanopartículas Metálicas/ultraestrutura , Regeneração , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X , Óxido de Zinco/síntese química
16.
Appl Environ Microbiol ; 86(16)2020 08 03.
Artigo em Inglês | MEDLINE | ID: mdl-32561578

RESUMO

Phloem-limited bacterial "Candidatus Liberibacter" species are associated with incurable plant diseases worldwide. Antimicrobial treatments for these pathogens are challenging due to the difficulty of reaching the vascular tissue they occupy at bactericidal concentrations. Here, in vitro antimicrobial mechanisms of Zinkicide TMN110 (ZnK), a nonphytotoxic zinc oxide (ZnO)-based nanoformulation, were compared to those of bulk ZnO (b-ZnO) using as a model the only culturable species of the genus, Liberibacter crescens Minimum bactericidal concentration (MBC) determination and time-kill assays showed that ZnK has a bactericidal effect against L. crescens, whereas b-ZnO is bacteriostatic. When ZnK was used at the MBC (150 ppm), its antimicrobial mechanisms included an increase in Zn solubility, generation of intracellular reactive oxygen species, lipid peroxidation, and cell membrane disruption; all of these were of greater intensity than those of b-ZnO. Inhibition of biofilms, which are important during insect vector colonization, was stronger by ZnK than by b-ZnO at concentrations between 2.5 and 10 ppm in batch cultures; however, neither ZnK nor b-ZnO removed L. crescens preformed biofilms when applied between 100 and 400 ppm. In microfluidic chambers simulating source-to-sink phloem movement, ZnK significantly outperformed b-ZnO in Zn mobilization and bactericidal activity against L. crescens planktonic cells in sink reservoirs. In microfluidic chamber assays assessing antibiofilm activity, ZnK displayed a significantly enhanced bactericidal activity against L. crescens individual attached cells as well as preformed biofilms compared to that of b-ZnO. The superior mobility and antimicrobial activity of ZnK in microenvironments make this formulation a promising product to control plant diseases caused by "Candidatus Liberibacter" species and other plant vascular pathogens.IMPORTANCE "Candidatus Liberibacter" species are associated with incurable plant diseases that have caused billions of dollars of losses for United States and world agriculture. Chemical control of these pathogens is complicated, because their life cycle combines intracellular vascular stages in plant hosts with transmission by highly mobile insect vectors. To date, "Candidatus Liberibacter" species are mostly unculturable, except for Liberibacter crescens, a member of the genus that has been used as a model for in vitro assays. Here, we evaluated the potential of Zinkicide (ZnK) as an antimicrobial against "Candidatus Liberibacter" species in batch cultures and under flow conditions, using L. crescens as a biological model. ZnK displayed bactericidal activity against L. crescens in batch cultures and showed increased mobility and bactericidal activity in microfluidic devices resembling "Candidatus Liberibacter" species natural habitats. ZnK performance observed here against L. crescens makes this compound a promising candidate to control plant diseases caused by vascular pathogens.


Assuntos
Antibacterianos/farmacologia , Citrus/microbiologia , Nanopartículas Metálicas , Floema/microbiologia , Doenças das Plantas/prevenção & controle , Rhizobiaceae/efeitos dos fármacos , Óxido de Zinco/farmacologia , Técnicas de Cultura Celular por Lotes , Microfluídica , Doenças das Plantas/microbiologia
17.
J Med Microbiol ; 69(6): 874-880, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32459619

RESUMO

Introduction. Biological adhesives and effective topical therapeutic agents that improve wound healing are urgently required for the treatment of chronic ulcers. A biodegradable adhesive based on a carbohydrate polymer with zinc oxide (CPZO) was shown to possess anti-inflammatory activity and enhance wound healing, but its bactericidal activity was unknown.Aim. To investigate the bactericidal activity of CPZO against bacteria commonly present as infectious agents in chronic wounds.Methodology. We examined the bactericidal activity of CPZO against three biofilm-producing bacteria (Staphylococcus aureus, Escherichia coli and Pseudomonas aeruginosa) through three strategies: bacterial suspension, biofilm disruption and in vitro wound biofilm model.Results. In suspension cultures, CPZO had direct, potent bactericidal action against S. aureus within 24 h, whereas E. coli took 7 days to be eliminated. By contrast, P. aeruginosa survived up to 14 days with CPZO. CPZO had biofilm disruption activity against clinical isolates of S. aureus in the anti-biofilm test. Finally, in the in vitro wound biofilm model, CPZO dramatically reduced the bacterial viability of S. aureus and P. aeruginosa.Conclusions. Together with its previously shown anti-inflammatory properties, the bactericidal activity of CPZO gives it the potential to be a first-line therapeutic option for chronic various ulcers and, possibly, other chronic ulcers, preventing or controlling microbial infections, and leading to the healing of such complicated chronic ulcers.


Assuntos
Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Infecções Bacterianas/tratamento farmacológico , Carboidratos/farmacologia , Polímeros/farmacologia , Cicatrização/efeitos dos fármacos , Óxido de Zinco/farmacologia , Infecções Bacterianas/microbiologia , Biofilmes/efeitos dos fármacos , Humanos , Testes de Sensibilidade Microbiana/métodos
18.
Int J Nanomedicine ; 15: 1457-1468, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32184598

RESUMO

Purpose: Zinc oxide nanoparticles (nZnO) have been widely used in the medicine field. Numerous mechanistic studies for nZnO's anticancer effects are merely performed under high concentration exposure. However, possible anticancer mechanisms of epigenetic dysregulation induced by low doses of nZnO are unclear. Methods: nZnO were characterized and bladder cancer T24 cells were treated with nZnO for 48 hrs at different exposure concentrations. Cell cycle, apoptosis, cell migration and invasion were determined. We performed qRT-PCR, Western blot and chromatin immunoprecipitation to detect the mRNA and protein levels of signaling pathway cascades for histone modification. Results: In this study, we investigated the potential anticancer effects and mechanisms of nZnO on histone modifications in bladder cancer T24 cells upon low-dose exposure. Our findings showed that low concentrations of nZnO resulted in cell cycle arrest at S phase, facilitated cellular late apoptosis, repressed cell invasion and migration after 48 hrs exposure. These anticancer effects could be attributed to increased RUNX3 levels resulting from reduced H3K27me3 occupancy on the RUNX3 promoter, as well as decreased contents of histone methyltransferase EZH2 and the trimethylation of histone H3K27. Our findings reveal that nZnO are able to enter into the cytoplasm and nucleus of T24 cells. Additionally, both particles and ions from nZnO may jointly contribute to the alteration of histone methylation. Moreover, sublethal nZnO-conducted anticancer effects and epigenetic mechanisms were not associated with oxidative stress or DNA damage. Conclusion: We reveal a novel epigenetic mechanism for anticancer effects of nZnO in bladder cancer cells under low-dose exposure. This study will provide experimental basis for the toxicology and cancer therapy of nanomaterials.


Assuntos
Antineoplásicos/farmacologia , Metilação de DNA/efeitos dos fármacos , Histonas/metabolismo , Nanopartículas Metálicas/uso terapêutico , Neoplasias da Bexiga Urinária/tratamento farmacológico , Óxido de Zinco/farmacologia , Antineoplásicos/administração & dosagem , Linhagem Celular Tumoral , Subunidade alfa 3 de Fator de Ligação ao Core/genética , Subunidade alfa 3 de Fator de Ligação ao Core/metabolismo , Relação Dose-Resposta a Droga , Epigênese Genética/efeitos dos fármacos , Humanos , Lisina/metabolismo , Nanopartículas Metálicas/administração & dosagem , Nanopartículas Metálicas/química , Estresse Oxidativo/efeitos dos fármacos , Regiões Promotoras Genéticas , Neoplasias da Bexiga Urinária/genética , Neoplasias da Bexiga Urinária/metabolismo , Óxido de Zinco/administração & dosagem
19.
Tumour Biol ; 42(3): 1010428320909999, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32129155

RESUMO

Cancer is the leading cause of death and exhausts human and economic resources for treatment and protection. Zinc oxide nanoparticles play an effective role in tumor treatment but with some cautions, such as overexpression of cytochrome P450, hepatic overload, and the mammalian target of rapamycin pathway resistance. Although lanthanides have antitumor activity, their use is limited. Therefore, the current study aims to improve the effectiveness of zinc oxide nanoparticle via doping with lanthanides, such as samarium. In vitro study revealed that samarium doped with zinc oxide showed more antitumor activity than the other lanthanides, and the antitumor activity depends on the concentration of samarium in the nanocomposite. The in vivo experiment on mice bearing Ehrlich solid tumor revealed that intramuscular injection of samarium/zinc oxide downregulates the expressions of CXCR4 and PI3K/Akt/mammalian target of rapamycin pathway in respect to Ehrlich solid tumor group. Regarding the apoptotic biomarkers, samarium/zinc oxide upregulates the apoptotic biomarker; Bax accompanied with the mitotic catastrophe which was indicated by cell cycle arrest in G2 phase. Moreover, samarium:zinc oxide nanoparticles exhibited minimum toxicity which was indicated by suppressed activities of cytochrome P450 and hepatic enzymes, including alanine transaminase and aspartate transaminase. In addition, the histopathological finding, as well as immunophenotyping results, appreciated the biochemical finding. Therefore, samarium:zinc oxide might be offered a new approach to improve the effectiveness of zinc oxide nanoparticles along with lower toxic effect. Also, samarium:zinc oxide nanoparticles can be a candidate as a new antitumor compound to detect its mode of action.


Assuntos
Antineoplásicos/farmacologia , Inibidores das Enzimas do Citocromo P-450/farmacologia , Receptores CXCR4/antagonistas & inibidores , Samário/farmacologia , Óxido de Zinco/farmacologia , Animais , Regulação para Baixo , Feminino , Camundongos , Nanopartículas , Receptores CXCR4/genética , Samário/efeitos adversos , Óxido de Zinco/efeitos adversos
20.
J Appl Microbiol ; 128(6): 1764-1775, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32027448

RESUMO

AIMS: The purpose of this study was to isolate Lactobacillus from gastrointestinal tract of healthy postweaning piglets and investigate its synergistic antimicrobial and probiotic effects with ZnO nanoparticles (nZnO). METHODS AND RESULTS: Of the 128 isolates, Lactobacillus plantarum BLPL03 was selected based on its excellent acid and bile salt tolerance properties. Lactobacillus plantarum BLPL03 was sensitive to ß-lactams, macrolides, amphenicols and cephalosporins, whereas it displayed the steady resistance to aminoglycosides, tetracyclines, quinolones and peptide antibiotics. In vitro analysis of antibacterial activities showed that L. plantarum BLPL03 inhibited the four common food-borne pathogenic bacteria including Escherichia coli O157:H7 CMCC 44828, Salmonella Typhimurium ATCC 13311, Staphylococcus aureus CMCC 26003 and Listeria monocytogenes CMCC 54007 in synergy with nZnO. Furthermore, the quantitative polymerase chain reaction test demonstrated that the combined administration of L. plantarum BLPL03 fermentation liquor (LFL) and nZnO synergistically elevated the faecal number of Bifidobacterium by 73·19-fold, and reduced the two potential enteropathogenic bacteria Enterobacteriaceae and Clostridium perfringens in mice challenged with Salm. Typhimurium. Finally, dietary supplementation with low dose of nZnO (20 mg kg-1 ) when combined with LFL administration enhanced final body weight, fur appearance and average daily gain, and decreased feed conversion ratio and diarrhoea incidence in weaned piglets. The faecal Bifidobacterium and Lactobacillus of piglets were dramatically enhanced by 81·96- and 3·15-fold, respectively, after administration of a mixture of nZnO and LFL. Meanwhile, combination of nZnO with LFL resulted in low levels of Bacteroides, Enterococcus, and Enterobacteriaceae. CONCLUSIONS: A combination of nZnO and LFL exhibits potential health-benefit properties for the control of gut microbial composition by their synergistic antimicrobial and probiotic effects. SIGNIFICANCE AND IMPACT OF THE STUDY: This study may provide a potential nutritional strategy to improve performance and gut health of animals with gut microbiota disorders caused by pathogen infections and weanling, and so on.


Assuntos
Antibacterianos/farmacologia , Lactobacillus plantarum/isolamento & purificação , Lactobacillus plantarum/fisiologia , Probióticos/farmacologia , Óxido de Zinco/farmacologia , Animais , Antibacterianos/administração & dosagem , Suplementos Nutricionais , Sinergismo Farmacológico , Fezes/microbiologia , Microbioma Gastrointestinal/efeitos dos fármacos , Trato Gastrointestinal/microbiologia , Lactobacillus plantarum/efeitos dos fármacos , Camundongos , Nanopartículas/administração & dosagem , Nanopartículas/química , Probióticos/administração & dosagem , Suínos/microbiologia , Desmame , Óxido de Zinco/administração & dosagem , Óxido de Zinco/química
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