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1.
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
2.
Food Chem Toxicol ; 135: 110906, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31669603

RESUMO

Zinc oxide nanoparticles (ZnONPs) have been widely used in food storage containers and food additives in daily life. However, the impact of oral intake of ZnONPs on nervous system is extremely limited, especially on children and adolescents. In this study, four weeks old mice were treated with either vehicle or ZnONPs suspension solution at 26 mg/kg by intragastric administration for 30 days. Our results demonstrated that oral ZnONPs exposure could induce pathological changes in gut and abnormal excitement of enteric neurons. Interestingly, we found that ZnONPs caused enhancement of 5-hydroxytryptamine (5-HT) in gut by activation of its biosynthesis, transport and receptors, and subsequently resulting in increased level of 5-HT in brain via gut-brain communication by blood. Our data also showed that there were no apparent changes on the expressions of interleukin (Il)-6, Il-1ß, C-C motif chemokine ligand 2 (Ccl2), tumor necrosis factor (Tnf) in gut and zinc chelator Mt2 in gut and cortex. Meanwhile, no significant changes were observed on the expressions of tryptophan hydroxylase type 1, 5-HT receptor 3A (Htr3a) and Htr4 in hippocampus and cortex. Our study indicate that oral ZnONPs exposure causes hyperfunction of 5-HT in gut in young mice which may further spread to brain via gut-brain communication.


Assuntos
Sistema Nervoso Entérico/efeitos dos fármacos , Hipocampo/efeitos dos fármacos , Nanopartículas Metálicas/química , Serotonina/metabolismo , Óxido de Zinco/farmacologia , Administração Oral , Animais , Sistema Nervoso Entérico/metabolismo , Hipocampo/metabolismo , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/metabolismo , Masculino , Nanopartículas Metálicas/administração & dosagem , Camundongos Endogâmicos C57BL , Serotonina/sangue , Junções Íntimas/efeitos dos fármacos , Óxido de Zinco/administração & dosagem
3.
J Appl Oral Sci ; 28: e20190105, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31800873

RESUMO

Calcium aluminate cement (CAC) has been highlighted as a promising alternative for endodontic use aiming at periapical tissue repair. However, its effects on dental pulp cells have been poorly explored. OBJECTIVE: This study assessed the impact of calcium chloride (CaCl2) and bismuth oxide (Bi2O3) or zinc oxide (ZnO) additives on odontoblast cell response to CAC. METHODOLOGY: MDPC-23 cells were exposed for up to 14 d: 1) CAC with 2.8% CaCl2 and 25% ZnO (CACz); 2) CAC with 2.8% CaCl2 and 25% Bi2O3 (CACb); 3) CAC with 10% CaCl2 and 25% Bi2O3 (CACb+); or 4) mineral trioxide aggregate (MTA), placed on inserts. Non-exposed cultures served as control. Cell morphology, cell viability, gene expression of alkaline phosphatase (ALP), bone sialoprotein (BSP), and dentin matrix protein 1 (DMP-1), ALP activity, and extracellular matrix mineralization were evaluated. Data were compared using ANOVA (α=5%). RESULTS: Lower cell density was detected only for MTA and CACb+ compared with Control, with areas showing reduced cell spreading. Cell viability was similar among groups at days one and three (p>0.05). CACb+ and MTA showed the lowest cell viability values at day seven (p>0.05). CACb and CACb+ promoted higher ALP and BSP expression compared with CACz (p<0.05); despite that, all cements supported ALP activity. Matrix mineralization were enhanced in CACb+ and MTA. CONCLUSION: In conclusion, CAC with Bi2O3, but not with ZnO, supported the expression of odontoblastic phenotype, but only the composition with 10% CaCl2 promoted mineralized matrix formation, rendering it suitable for dentin-pulp complex repair.


Assuntos
Compostos de Alumínio/química , Compostos de Alumínio/farmacologia , Compostos de Cálcio/química , Compostos de Cálcio/farmacologia , Cimentos Dentários/química , Cimentos Dentários/farmacologia , Polpa Dentária/citologia , Polpa Dentária/efeitos dos fármacos , Fosfatase Alcalina/análise , Fosfatase Alcalina/efeitos dos fármacos , Animais , Bismuto/química , Bismuto/farmacologia , Cloreto de Cálcio/química , Cloreto de Cálcio/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Combinação de Medicamentos , Expressão Gênica/efeitos dos fármacos , Teste de Materiais , Camundongos , Odontoblastos/efeitos dos fármacos , Óxidos/química , Óxidos/farmacologia , Reprodutibilidade dos Testes , Silicatos/química , Silicatos/farmacologia , Fatores de Tempo , Óxido de Zinco/química , Óxido de Zinco/farmacologia
4.
Arch Oral Biol ; 111: 104640, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31884336

RESUMO

OBJECTIVE: Streptococcus mutans (S. mutans), the main pathogen of dental caries, could be well killed by Ag/ZnO nanocomposite. However, effects on virulence factors remain to be elucidated. This study investigated effects of Ag/ZnO at sub-minimum inhibitory concentrations (sub-MICs) on virulence factors of S. mutans and related genes expressions. DESIGN: Effects of Ag/ZnO on the growth of S. mutans was investigated by growth curves and MTT staining method. The influence of Ag/ZnO at sub-MICs on biofilm formation was measured by the crystal violet staining method and observed by a scanning electron microscopy. Adherence, cell-surface hydrophobicity, acidogenicity and extracellular polysaccharides (EPS) of S. mutans after treatment by Ag/ZnO at sub-MICs were also investigated. Virulence factors related genes expressions after treated by Ag/ZnO at 1/2 MIC was conducted by the quantitative real-time PCR (qRT-PCR) method. RESULTS: Sub-MICs of Ag/ZnO exhibited a dose-dependent inhibition on the virulence factors of S. mutans. Specially, Ag/ZnO at 1/2 MIC decreased 69.00 % biofilm formation, 31.78 % sucrose-independent and 48.08 % sucrose-dependent adherence, 69.44 % cell-surface hydrophobicity and 72.45 % water-soluble and 90.60 % water-insoluble EPS. Furthermore, the expression of virulence factors related genes was significantly suppressed by Ag/ZnO at 1/2 MIC. CONCLUSIONS: Ag/ZnO at sub-MICs inhibited multiple virulence factors of S. mutans through downregulating the related genes. Ag/ZnO nanocomposite could be used for prevention of dental caries at low dosage.


Assuntos
Antibacterianos/farmacologia , Prata/farmacologia , Streptococcus mutans/efeitos dos fármacos , Fatores de Virulência/metabolismo , Óxido de Zinco/farmacologia , Biofilmes , Testes de Sensibilidade Microbiana , Nanocompostos
5.
Int J Food Microbiol ; 312: 108375, 2020 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-31669767

RESUMO

Recently, oxo-biodegradable polymers have attracted much attention due to taking less time to break down after disposal in comparison to ordinary polymers. Polyvinyl alcohol/gelatin (PVA/G) nanocomposite films, containing ZnO, TiO2 or ZnO/TiO2 nanoparticles supported on 4A zeolite (4A z), are novel active packaging that can control the release of antimicrobial compounds. The present study assessed the efficacy of PVA/G nanocomposite films with 1.5% (w/w) ZnO/4A z (treatment 1), 1.5% (w/w) TiO2/4A z (treatment 2), or 1% (w/w) ZnO, TiO2/4A z (treatment 3) in controlling the microbial load and maintaining the sensory qualities of white shrimp during storage at 4 ±â€¯1 °C. Firstly, the optimum concentration of each material for addition to the film was determined by micro-dilution and disc diffusion. Secondly, the specimens were checked for total viable count (TVC), as well as the counts of each of Pseudomonas spp., Enterobacteriaceae, Shewanella putrefaciens, inoculated Staphylococcus aureus, Listeria monocytogenes, and Escherichia coli O157:H7. According to the results, the PVA/G nanocomposite films containing treatments 1-3 significantly decreased the number of bacteria in the treatment group in comparison to the control group (P < .05). The results of the antimicrobial activity of the three treatments by using the disc diffusion method revealed that the inhibition zone varied from 8.11 ±â€¯0.02 to 12.63 ±â€¯0.04 mm. Also it should be noted that, the finding of micro-dilution test varied from 1 ±â€¯0.01 to 3 ±â€¯0.01. The ZnO, TiO2/4A z nanocomposite had a significantly greater antimicrobial impact against Gram-negative bacteria compared to Gram-positive bacteria (P < .05). Finally, the microbiological and sensory investigation of the efficacy of the PVA/G nanocomposite films as active packaging materials revealed a considerable improvement in shrimp shelf life (12 days) in comparison to the control (6 days). Therefore, these nanocomposite films can be used as novel active packaging in the maintenance of the microbial load and sensory qualities of shrimp.


Assuntos
Antibacterianos/farmacologia , Embalagem de Alimentos/métodos , Armazenamento de Alimentos/métodos , Penaeidae/microbiologia , Titânio/farmacologia , Zeolitas/farmacologia , Óxido de Zinco/farmacologia , Animais , Carga Bacteriana/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Gelatina/farmacologia , Listeria monocytogenes/efeitos dos fármacos , Nanocompostos , Nanopartículas , Álcool de Polivinil/farmacologia , Refrigeração , Staphylococcus aureus/efeitos dos fármacos
6.
Food Chem ; 309: 125566, 2020 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-31706674

RESUMO

Nanostructured coatings made with chitosan (100%Q), alginate (100%A) and blends of 50%Q-50%A; 90%Q-10%A and 90%A-10%Q, were added with (1%v/vgel) of nanoZnO and applied to guavas (Psidium guajava L.). After the coating application, fruits were stored for 15 days at 21 ±â€¯1 °C and 80 ±â€¯2% RH. To determine the effect on ripening process, fruits were submitted to water loss, texture, color, rot index, and physic-chemical assays. The results showed that coatings are able to prevent rot appearance in every sample, corroborating with the antibacterial action of nanoZnO. Coatings made with alginate and 90%A did not delay the maturation process, however, chitosan matrices (100%Q or 90%Q) protected fruits against excessive mass loss and retarded physic-chemical changes related to maturation. The experiment or study showed that it is possible to extend guava shelf life with ZnO nanostructured coatings with 100%Q or 90%Q-10%A for up to twenty days versus seven days of uncoated fruits.


Assuntos
Antibacterianos/farmacologia , Conservação de Alimentos/métodos , Frutas , Psidium , Alginatos/farmacologia , Quitosana/farmacologia , Nanopartículas/química , Óxido de Zinco/farmacologia
8.
Photochem Photobiol Sci ; 19(1): 66-70, 2020 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-31845952

RESUMO

Photoprotection, including the use of sunscreen, has been shown to decrease the development of keratinocyte cancers and melanoma. Due to concerns about the environmental effects of some organic UVR filters, several locations across the world have begun to pass legislation banning the use of these ingredients in sunscreens. Furthermore, the health effects of several organic UVR filters have also been called into question and a recent proposal by the US FDA has resulted in public confusion about the safety of sunscreens. The aim of this article is to discuss FDA regulation of sunscreens and to review the environmental and health effects of oxybenzone and octinoxate. Ultimately, as dermatologists, our recommendations are to continue to encourage people to practice proper photoprotection including photoprotective clothing, staying in the shade while outdoors, and applying sunscreen to exposed areas. For those concerned about the potential environmental and health effects of organic UVR filters, inorganic/mineral UVR filter (namely, zinc oxide and titanium dioxide)-based sunscreens can be used.


Assuntos
Protetores Solares/legislação & jurisprudência , United States Food and Drug Administration/legislação & jurisprudência , Benzofenonas/farmacologia , Cinamatos/farmacologia , Humanos , Protetores Solares/farmacologia , Titânio/farmacologia , Estados Unidos , Óxido de Zinco/farmacologia
9.
Int J Nanomedicine ; 14: 9395-9410, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31819439

RESUMO

The inappropriate use of antimicrobials has resulted in the selection of resistant strains. Thus, a great number of studies have focused on the investigation of new antimicrobial agents. The use of zinc oxide nanoparticles (ZnO NPs) to optimise the fight against microbial resistance has been receiving increased attention due to the non-specific activity of inorganic antimicrobial agents. The small particle size and the high surface area of ZnO NPs can enhance antimicrobial activity, causing an improvement in surface reactivity. In addition, surface modifiers covering ZnO NPs can play a role in mediating antimicrobial activity since the surface properties of nanomaterials alter their interactions with cells; this may interfere with the antimicrobial effect of ZnO NPs. The possibility of using surface modifiers with groups toxic to microorganisms can improve the antimicrobial activity of ZnO NPs. Understanding the exact toxicity mechanisms is crucial to elucidating the antimicrobial activity of ZnO NPs in bacteria and fungi. Therefore, this review aims to describe the mechanisms of ZnO NPs toxicity against fungi and bacteria and how the different structural and physical-chemical characteristics of ZnO NPs can interfere in their antimicrobial activity.


Assuntos
Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Nanopartículas Metálicas/química , Óxido de Zinco/farmacologia , Bactérias/efeitos dos fármacos , Fungos/efeitos dos fármacos , Relação Estrutura-Atividade
10.
Life Sci ; 239: 117011, 2019 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-31669241

RESUMO

Diabetes mellitus (DM) is a multifaceted and costly disease, which requires serious attention. Finding a cheaper anti-diabetic alternative that can act on multiple disease-related targets and pathways is the ultimate treatment goal for DM. Nanotechnology has offered some exciting possibilities in biomedical and drug delivery applications. Zinc oxide nanoparticles (ZnO-NPs), a novel agent to deliver zinc, have great implications in many disease therapies including DM. This review summarizes the pharmacological mechanisms by which ZnO-NPs alleviate DM and diabetic complications. Research implications and future perspectives were also discussed.


Assuntos
Diabetes Mellitus/tratamento farmacológico , Hipoglicemiantes/uso terapêutico , Nanopartículas Metálicas/uso terapêutico , Óxido de Zinco/uso terapêutico , Animais , Complicações do Diabetes/tratamento farmacológico , Sistemas de Liberação de Medicamentos , Humanos , Hipoglicemiantes/farmacologia , Óxido de Zinco/farmacologia
11.
Int J Nanomedicine ; 14: 7809-7822, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31576125

RESUMO

Introduction: Nanoparticles (NPs) can be toxic due to their nano-range sizes. Zinc oxide (ZnO) has good biocompatibility and is commercially used in cosmetics. Moreover, ZnO NPs have potential biomedical uses, but their safety remains unclear. Methods: A range of doped ZnO NPs was evaluated for antileishmanial activity and in vitro toxicity in brine shrimp and human macrophages, and N-doped ZnO NPs were evaluated for in vivo toxicity in male BALB/C mice. N-doped ZnO NPs were administered via two routes: intra-peritoneal injection and topically as a paste. The dosages were 10, 50, and 100 mg/kg/day for 14 days. Results: Topical administration was safe at all dosages, but intra-peritoneal injection displayed toxicity at higher doses, namely, 50 and 100 mg/kg/day. The pathological results for the i.p. dose groups were mild to severe degenerative changes in parenchyma cells, increases in Kupffer cells, disappearance of hepatic plates, increases in cell size, ballooning, cytoplasmic changes, and nuclear pyknosis in the liver. Kidney histology was also altered in the i.p. administration group (dose 100 mg/kg/day), with inflammatory changes in the focal area. We associate pathological abnormalities with the presence of doped ZnO NPs at the diseased site, which was verified by PIXE analysis of the liver and kidney samples of the treated and untreated mice groups. Conclusion: The toxicity of the doped ZnO NPs can serve as an essential determinant for the effects of ZnO NPs on environmental toxicity and can be used for guidelines for safer use of ZnO-based nanomaterials in topical treatment of leishmaniasis and other biomedical applications.


Assuntos
Anti-Helmínticos/farmacologia , Nanopartículas/toxicidade , Óxido de Zinco/farmacologia , Óxido de Zinco/toxicidade , Animais , Artemia/efeitos dos fármacos , Morte Celular/efeitos dos fármacos , Humanos , Concentração Inibidora 50 , Rim/efeitos dos fármacos , Rim/patologia , Leishmania/efeitos dos fármacos , Fígado/efeitos dos fármacos , Fígado/patologia , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Masculino , Camundongos Endogâmicos BALB C
12.
Int J Nanomedicine ; 14: 8195-8208, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31632027

RESUMO

Background: Zinc oxide nanoparticles (ZnO NPs) are used in modern cancer therapy based on their specific target, efficacy, low toxicity and biocompatibility. The photocatalytic performance of Zinc oxide (ZnO) nanocomposites with hyaluronic acid (HA) was used to study anticancer properties against various human cancer cell lines. Methods: Zinc oxide (ZnO) nanocomposites functionalized by hyaluronic acid (HA) were prepared by a co-precipitation method (HA-ZnONcs). The submicron-flower-shaped nanocomposites were further functionalized with ginsenoside Rh2 by a cleavable ester bond via carbodiimide chemistry to form Rh2HAZnO. The physicochemical behaviors of the synthesized ZnO nanocomposites were characterized by various analytical and spectroscopic techniques. We carried out 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyl tetrazolium bromide (MTT) assay to evaluate the toxicity of Rh2HAZnO in various human cancer cells (A549, MCF-7, and HT29). Furthermore, to confirm the apoptotic effects of Rh2HAZnO and to determine the role of the Caspase-9/p38 MAPK pathways by various molecular techniques such as RT-PCR and Western blotting. Furthermore, Rh2HAZnO induced morphological changes of these cell lines, mainly intracellular reactive oxygen species (ROS) were observed by ROS staining and nucleus by Hoechst staining. Results: We confirmed that Rh2HAZnO exhibits the anti-cancer effects on A549 lung cancer, HT29 colon cancer, and MCF7 breast cancer cells. Moreover, intracellular reactive oxygen species (ROS) were observed in three cancer cell lines. Rh2HAZnO induced apoptotic process through p53-mediated pathway by upregulating p53 and BAX and downregulating BCL2. Specifically, Rh2HAZnO induced activation of cleaved PARP (Asp214) in A549 lung cancer cells and upregulated Caspase-9/phosphorylation of p38 MAPK in other cell lines (HT29 and MCF-7). Furthermore, Rh2HAZnO induced morphological changes in the nucleus of these cell lines. Conclusion: These results suggest that the potential anticancer activity of novel Rh2HAZnO nanoparticles might be linked to induction of apoptosis through the generation of ROS by activation of the Caspase-9/p38 MAPK pathway.


Assuntos
Apoptose/efeitos dos fármacos , Caspase 9/metabolismo , Ginsenosídeos/farmacologia , Ácido Hialurônico/farmacologia , Luminescência , Nanopartículas/química , Óxido de Zinco/farmacologia , Células A549 , Linhagem Celular Tumoral , Núcleo Celular/efeitos dos fármacos , Núcleo Celular/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Dano ao DNA , Humanos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Nanopartículas/ultraestrutura , Espécies Reativas de Oxigênio/metabolismo , Óxido de Zinco/química , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
13.
Mater Sci Eng C Mater Biol Appl ; 105: 110077, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31546450

RESUMO

Although silver based nanofibers possess excellent bactericidal and bacteriostatic characteristics. However, excess release/contact with silver may induce harmful side-effects including carcinoma, argyria, argyrosis and allergies. Similarly, silver depletion may limit prolonged antibacterial activities as well. Thus present research proposes electrospun CA/ZnO/AgNPs composite nanofibers for biologically safer and sustained antibacterial applications. The ZnO/AgNPs were synthesized using dopamine hydrochloride (Dopa) as reducing agent to immobilize AgNPs on ZnO nanoparticles. A simple solution-mixing procedure effectively generated AgNPs on ZnO nanoparticles. Strong adhesive characteristics of Dopa initiate adsorption of silver ions on ZnO nanoparticle surfaces and its metal ion reducing properties generate AgNPs. Additionally, the Dopa mediation generates strongly adhered AgNPs. The ZnO/AgNPs were used to fabricate CA/ZnO/AgNPs nanofibers. Characterization techniques, XRD, XPS, TEM, FTIR and SEM confirmed synthesis of nanocomposites. Crystallite sizes of ZnO and AgNPs calculated by Debye-Scherrer equation were 17.85 nm and 11.68 nm respectively. Antibacterial assays confirmed CA/ZnO/AgNP's effectiveness in growth inhibition of E. coli and S. aureus strains on agar plate and in liquid medium. The nanofiber composites demonstrated 100% bactericidal properties against both the test strains. Bacterial growth inhibition in LB medium for 108 h indicated suitability of CA/ZnO/AgNPs composite nanofibers in sustained antibacterial applications such as antibacterial wound dressings and other applications demanding sustained antimicrobial properties.


Assuntos
Antibacterianos , Escherichia coli/crescimento & desenvolvimento , Nanopartículas Metálicas/química , Nanofibras/química , Prata , Staphylococcus aureus/crescimento & desenvolvimento , Óxido de Zinco , Antibacterianos/química , Antibacterianos/farmacologia , Prata/química , Prata/farmacologia , Óxido de Zinco/química , Óxido de Zinco/farmacologia
14.
Mater Sci Eng C Mater Biol Appl ; 104: 109968, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31500003

RESUMO

This is a report on the antibacterial activity of ZnO and CuO nanoparticles synthesized via sol-gel method. The studies were performed on Gram-positive Staphylococcus aureus and Gram-negative Escherichia coli and Pseudomonas aeruginosa bacteria using disc and well diffusion methods, bioluminescence and optical density analysis. The results show a strong decline of bacterial strains after a short contact with nanoparticles. The modelling allowed clarifying the bacterial sensitivity of toxic agents at different stages of their population evolution kinetics. It was concluded that the bacterial suppression is most effective at the exponential growth phase while it is of a lower effectiveness at the lag and stationary phases. The CuO and ZnO nanoparticles showed comparable effectiveness at the exponential growth phase. In the same time, ZnO was almost inactive at the lag phase and of lower effectiveness at the stationary phase, at which CuO conserved a significant activity.


Assuntos
Antibacterianos/farmacologia , Cobre/farmacologia , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Nanopartículas Metálicas/química , Óxido de Zinco/farmacologia , Testes de Sensibilidade Microbiana/métodos , Tamanho da Partícula
15.
J Trace Elem Med Biol ; 56: 169-177, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31479800

RESUMO

BACKGROUND: Zinc is an essential trace element which is involved in controlling oxidative stress, growth and immune system by regulating inflammatory cytokines. Gouty arthritis is the inflammation of joints and tissues caused by the accumulation of monosodium urate crystals. METHOD AND OBJECTIVE: This study involved the oral administration of zinc oxide nanoparticles at a various concentration (5 ppm, 10 ppm, and 20 ppm) and study their antioxidant and anti-gout effects on Balb/C mice. Various parameters such as ROS, superoxide, peroxide, catalase, TBARS, RFTs, LFTs, lipid profile and blood count were studied. RESULTS: ZnO nanoparticles at the concentrations of 10 and 20 ppm were significant (P < 0.001) in reducing serum uric acid concentration thus treating gouty arthritis. Reactive oxygen species and thiobarbituric acid reactive substances were significantly increased in comparison to zinc oxide nanoparticles treated groups. Furthermore, blood count and LFTs also showed the effectiveness of zinc oxide in the reduction of hyperuricemia. Histopathological analysis showed no apparent changes in liver, kidney and muscles tissues. CONCLUSION: Zinc oxide nanoparticles can be effective in reducing oxidative stress and the treatment of gouty arthritis.


Assuntos
Antioxidantes/uso terapêutico , Artrite Gotosa/tratamento farmacológico , Nanopartículas/administração & dosagem , Óxido de Zinco/administração & dosagem , Óxido de Zinco/uso terapêutico , Administração Oral , Animais , Antioxidantes/farmacologia , Artrite Gotosa/sangue , Rim/fisiopatologia , Lipídeos/sangue , Fígado/fisiopatologia , Camundongos Endogâmicos BALB C , Nanopartículas/ultraestrutura , Especificidade de Órgãos , Difração de Raios X , Zinco/sangue , Óxido de Zinco/farmacologia
16.
J Mater Sci Mater Med ; 30(9): 101, 2019 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-31473826

RESUMO

Diabetes mellitus is the most common metabolic disorder with a high mortality and morbidity rate. A new promising strategy to treat DM is pancreatic tissue engineering. We described a 3D culture system accompanied by signaling factors to differentiate hEnSCs into IPCs in the presence of nZnO. We isolated EnSCs and cultured it in DMEM/F12 medium. Nanofibrous PLA/Cs scaffold was prepared through the electrospinning method. The morphological properties of the scaffolds and cells were evaluated by SEM. MTT assay was used to investigate the metabolic activity of the hEnSCs cultured on the scaffolds and a four-stage protocol was applied to differentiate hEnSCs. The differentiated cells were tested for pancreatic markers by immunocytochemistry, qRT-PCR and DTZ staining. The results of this study revealed that hEnSCs cultured on PLA/Cs scaffold and treated with nZnO can efficiently differentiate into IPCs. The examination of differentiated cell morphology showed their near similarity with pancreatic islet cells, and DTZ staining emphasized the presence of insulin granules inside their cytoplasm. Moreover, qRT-PCR and immunofluorescent staining results showed the efficient expression of specific gene markers of IPCs in resultant differentiated cells. Moreover, PLA/CS and nZnO were able to provide a good nanoenvironment for the differentiation of hEnSCs into IPCS the in presence of other molecules.


Assuntos
Transdiferenciação Celular/efeitos dos fármacos , Endométrio/citologia , Células Secretoras de Insulina/efeitos dos fármacos , Nanofibras/química , Células-Tronco/efeitos dos fármacos , Tecidos Suporte/química , Óxido de Zinco/farmacologia , Células Cultivadas , Feminino , Humanos , Insulina/metabolismo , Células Secretoras de Insulina/fisiologia , Teste de Materiais , Nanopartículas Metálicas/química , Transdução de Sinais/efeitos dos fármacos , Células-Tronco/citologia , Células-Tronco/fisiologia , Engenharia Tecidual/métodos , Óxido de Zinco/química
17.
J Biomed Sci ; 26(1): 70, 2019 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-31500628

RESUMO

BACKGROUND: Currently available anti-influenza drugs are often associated with limitations such as toxicity and the appearance of drug-resistant strains. Therefore, there is a pressing need for the development of novel, safe and more efficient antiviral agents. In this study, we evaluated the antiviral activity of zinc oxide nanoparticles (ZnO-NPs) and PEGylated zinc oxide nanoparticles against H1N1 influenza virus. METHODS: The nanoparticles were characterized using the inductively coupled plasma mass spectrometry, x-ray diffraction analysis, and electron microscopy. MTT assay was applied to assess the cytotoxicity of the nanoparticles, and anti-influenza activity was determined by TCID50 and quantitative Real-Time PCR assays. To study the inhibitory impact of nanoparticles on the expression of viral antigens, an indirect immunofluorescence assay was also performed. RESULTS: Post-exposure of influenza virus with PEGylated ZnO-NPs and bare ZnO-NPs at the highest non-toxic concentrations could be led to 2.8 and 1.2 log10 TCID50 reduction in virus titer when compared to the virus control, respectively (P < 0.0001). At the highest non-toxic concentrations, the PEGylated and unPEGylated ZnO-NPs led to inhibition rates of 94.6 and 52.2%, respectively, which were calculated based on the viral loads. There was a substantial decrease in fluorescence emission intensity in viral-infected cell treated with PEGylated ZnO-NPs compared to the positive control. CONCLUSIONS: Taken together, our study indicated that PEGylated ZnO-NPs could be a novel, effective, and promising antiviral agent against H1N1 influenza virus infection, and future studies can be designed to explore the exact antiviral mechanism of these nanoparticles.


Assuntos
Antivirais/farmacologia , Vírus da Influenza A Subtipo H1N1/efeitos dos fármacos , Nanopartículas Metálicas , Polietilenoglicóis/farmacologia , Óxido de Zinco/farmacologia , Testes de Sensibilidade Microbiana , Nanomedicina
18.
Chemosphere ; 237: 124359, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31394455

RESUMO

The effect of zinc oxide nanoparticles (ZnO NPs) and zinc sulfide nanoparticles (ZnS NPs) on the toxicity of sewage sludges in sewage sludge-amended soils was investigated with respect to plant- (Lepidium sativum) and soil- (Folsomia candida) species. The toxicity of porewater obtained from the tested soils towards Vibrio fischeri (Microtox®) was also investigated. Two sewage sludges (SSL1 and SSL2) with different organic matter content were amended with nanoparticles. Depending on the type of biotest and the type of sewage sludge, different effects of ZnO or ZnS NPs on the toxicity of sewage sludge-amended soil were observed. In general, ZnO and ZnS NPs stimulated root growth for SSL1 or reduced the harmful impact of SSL2 on the root growth of L. sativum roots. Greater stimulation or inhibition of root growth was observed for the ZnO than ZnS NPs. The unfavorable effect of ZnO/ZnS NPs on F. candida mortality and reproduction was observed at a concentration of ZnO/ZnS in sewage sludge ≥250 mg/kg. Generally, there were no significant differences between ZnO and ZnS NPs toxicity towards F. candida. Aging for 45 days of sewage sludge-amended soil containing NPs affected ZnO and ZnS NPs toxicity to all tested organisms. In the most cases, the toxicity decreased after 45 days of aging for plant (L. sativum) and invertebrates (F. candida). The toxicity of porewater to V. fischeri from sewage sludge-amended soil contains ZnO NPs did not change, while in the case of ZnS NPs, the toxicity increased after 45 days of aging.


Assuntos
Bactérias/efeitos dos fármacos , Invertebrados/efeitos dos fármacos , Nanopartículas/química , Plantas/efeitos dos fármacos , Solo/química , Aliivibrio fischeri/efeitos dos fármacos , Animais , Artrópodes/efeitos dos fármacos , Lepidium sativum/efeitos dos fármacos , Esgotos , Poluentes do Solo/análise , Sulfetos/farmacologia , Compostos de Zinco/farmacologia , Óxido de Zinco/farmacologia
19.
J Appl Microbiol ; 127(5): 1391-1402, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31386785

RESUMO

AIMS: This work aimed to evaluate the antimicrobial activity of pure (ZnO) and doped (ZnMgO) zinc oxide (ZnO) nanoparticles on bacterial pathogens and Saccharomyces cerevisiae to confirm their applicability as an alternative to antibiotics and to estimate their biocompatibility. METHODS AND RESULTS: Microbial growth inhibition on agar plates, microbial viability and adaptation tests in broth with ZnO nanoparticles, spore germination, random amplified polymorphic DNA and SDS-PAGE analysis were conducted to evaluate the effects of ZnO nanoparticles on cell morphology, viability, DNA damage and protein production. For this purpose, Escherichia coli, Salmonella, Listeria monocytogenes, Staphylococcus aureus, Bacillus subtilis and S. cerevisiae were studied after the addition of ZnO nanoparticles to the growth media. The contact with ZnO nanoparticles produced changes in morphology, shape, viability, DNA arrangement (DNA fingerprints) and protein content (SDS-PAGE) in treated cells. CONCLUSIONS: As reported in this study, ZnO nanoparticles have an antimicrobial effect on both prokaryotic and eukaryotic cells. Before using ZnO nanoparticles as antimicrobial agents, it is important to evaluate the target because their effect depends on their composition, size and dose. SIGNIFICANCE AND IMPACT OF THE STUDY: We believe that the results obtained can help to optimize manufactured metal oxide nanoparticles in terms of their composition, size and working concentration. The parameters obtained directly define the applicability and biocompatibility of ZnO nanoparticles and thus are essential for any utilization in food, medicine and industry where pathogen control is crucial.


Assuntos
Anti-Infecciosos/farmacologia , Bacillus subtilis/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Nanopartículas/toxicidade , Saccharomyces cerevisiae/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos , Óxido de Zinco/farmacologia , Anti-Infecciosos/química , Bacillus subtilis/crescimento & desenvolvimento , Escherichia coli/crescimento & desenvolvimento , Listeria monocytogenes/efeitos dos fármacos , Listeria monocytogenes/crescimento & desenvolvimento , Testes de Sensibilidade Microbiana , Viabilidade Microbiana/efeitos dos fármacos , Nanopartículas/química , Saccharomyces cerevisiae/crescimento & desenvolvimento , Staphylococcus aureus/crescimento & desenvolvimento , Óxido de Zinco/química
20.
ACS Appl Mater Interfaces ; 11(34): 31411-31420, 2019 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-31373785

RESUMO

Cutaneous hemorrhage often occurs in daily life which may cause infection and even amputation. This research aims to develop a novel chitosan dressing impregnated with ZnO/N-halamine hybrid nanoparticles for quick antibacterial performance, outstanding hemostatic potential, high porosity, and favorable swelling property through combining sonication and lyophilization processing. After 30 days of storage, about 90% bacterial cell viability loss could be observed toward both Gram-positive Staphylococcus aureus and Gram-negative Escherichia coli O157:H7 within 30 min of contact by colony counting method. The hybrids assembled much more platelet and red blood cell as compared with pure chitosan control. Moreover, the lower blooding clotting index value gave evidence that these composites could control hemorrhaging and reduce the probability of wound infection. No potential skin irritation and toxicity were detected using in vitro cytocompatibility and a skin stimulation test. Therefore, this work demonstrated a facile and cost-effective approach for the preparation of N-halamine-based hybrid sponges which show promising application for wound dressings.


Assuntos
Antibacterianos , Bandagens , Escherichia coli O157/crescimento & desenvolvimento , Staphylococcus aureus/crescimento & desenvolvimento , Óxido de Zinco , Animais , Antibacterianos/química , Antibacterianos/farmacologia , Coagulação Sanguínea/efeitos dos fármacos , Viabilidade Microbiana/efeitos dos fármacos , Coelhos , Óxido de Zinco/química , Óxido de Zinco/farmacologia
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