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1.
Chem Biol Interact ; 312: 108814, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31509734

RESUMO

Nanotechnology is a growing science that may provide several new applications for medicine, food preservation, diagnostic technologies, and sanitation. Despite its beneficial applications, there are several questions related to the safety of nanomaterials for human use. The development of nanotechnology is associated with some concerns because of the increased risk of carcinogenesis following exposure to nanomaterials. The increased levels of reactive oxygen species (ROS) that are due to exposure to nanoparticles (NPs) are primarily responsible for the genotoxicity of metal NPs. Not all, but most metal NPs are able to directly produce free radicals through the release of metal ions and through interactions with water molecules. Furthermore, the increased production of free radicals and the cell death caused by metal NPs can stimulate reduction/oxidation (redox) reactions, leading to the continuous endogenous production of ROS in a positive feedback loop. The overexpression of inflammatory mediators, such as NF-kB and STATs, the mitochondrial malfunction and the increased intracellular calcium levels mediate the chronic oxidative stress that occurs after exposure to metal NPs. In this paper, we review the genotoxicity of different types of metal NPs and the redox mechanisms that amplify the toxicity of these NPs.


Assuntos
Nanopartículas Metálicas/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Animais , Cálcio/metabolismo , Dano ao DNA/efeitos dos fármacos , Aditivos Alimentares/química , Humanos , Nanopartículas Metálicas/química , Nanopartículas Metálicas/uso terapêutico , Neoplasias/tratamento farmacológico , Oxirredução , Espécies Reativas de Oxigênio/metabolismo
2.
Int J Nanomedicine ; 14: 5147-5157, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31371953

RESUMO

Background: Kaempferol (K) is a recognized anticancer drug that can conjugate with small-size gold nanoclusters (AuNCs). Materials and methods: K-AuNCs were synthesized and their use as an anticancer drug was explored using A549 lung cancer cells. Colony formation and cell migration assays were carried out. The morphology of the K-AuNCs treated A549 cells was explored using bio-atomic force microscopy. Results: The K-AuNCs were 1-3 nm in diameter and emitted strong fluorescent at 650 nm following excitation at 550 nm. The stretching and bending nature of the K-AuNCs were analyzed by the Fourier transform infrared spectroscopy. The presence of kaempferol in the AuNCs were confirmed by the PL spectroscopy. Conclusion: The synthesized K-AuNCs mainly targeted and damaged the nuclei of the cancer cells. This composite nanocluster was less toxicity to the normal human cell and higher toxicity to the A549 lunch cancer cell and these material is potential for anticancer drug delivery and bio imaging applications.


Assuntos
Antineoplásicos/uso terapêutico , Ouro/química , Quempferóis/uso terapêutico , Neoplasias Pulmonares/tratamento farmacológico , Nanopartículas Metálicas/química , Células A549 , Antineoplásicos/química , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Núcleo Celular/efeitos dos fármacos , Núcleo Celular/patologia , Proliferação de Células/efeitos dos fármacos , Forma Celular/efeitos dos fármacos , Humanos , Quempferóis/farmacologia , Nanopartículas Metálicas/toxicidade , Nanopartículas Metálicas/ultraestrutura , Fenômenos Ópticos , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
3.
J Photochem Photobiol B ; 197: 111541, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31272033

RESUMO

Here, we report the novel fabrication of ZnO nanoparticles using the Costus igneus leaf extract. Gas chromatography-mass spectrometry (GC-MS) and proton nuclear magnetic resonance (1H NMR) spectroscopy to determine the bioactive components present in the plant extract. The synthesis of Ci-ZnO NPs (C. igneus- coated zinc oxide nanoparticles) was accomplished using a cost-effective and simple technique. Ci-ZnO NPs were specified using UV-visible spectroscopy, FTIR, XRD, and TEM. Ci-ZnO NPs was authenticated by UV-Vis and exhibited a peak at 365 nm. The XRD spectra proved the crystalline character of the Ci-ZnO NPs synthesized as hexagonal wurtzite. The FTIR spectrum illustrated the presence of possible functional groups present in Ci-ZnO NPs. The TEM micrograph showed evidence of the presence of a hexagonal organization with a size of 26.55 nm typical of Ci-ZnO NPs. The α-amylase and α-glucosidase inhibition assays demonstrated antidiabetic activity of Ci-ZnO NPs (74 % and 82 %, respectively), and the DPPH [2,2-diphenyl-1-picrylhydrazyl hydrate] assay demonstrated the antioxidant activity of the nanoparticles (75%) at a concentration of 100 µg/ml. The Ci-ZnO NPs exhibited promising antibacterial and biofilm inhibition activity against the pathogenic bacteria Streptococcus mutans, Lysinibacillus fusiformis, Proteus vulgaris, and Vibrio parahaemolyticus. Additionally, the Ci-ZnO NPs showed biocompatibility with mammalian RBCs with minimum hemolytic activity (0.633 % ±â€¯0.005 %) at a concentration of 200 µg/ml.


Assuntos
Antibacterianos/farmacologia , Antioxidantes/química , Biofilmes/efeitos dos fármacos , Nanopartículas Metálicas/química , Extratos Vegetais/química , Óxido de Zinco/química , Antibacterianos/síntese química , Antibacterianos/química , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Costus/química , Costus/metabolismo , Eritrócitos/citologia , Eritrócitos/efeitos dos fármacos , Eritrócitos/metabolismo , Cromatografia Gasosa-Espectrometria de Massas , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Negativas/fisiologia , Bactérias Gram-Positivas/efeitos dos fármacos , Bactérias Gram-Positivas/fisiologia , Química Verde , Hemólise/efeitos dos fármacos , Humanos , Insulina/química , Nanopartículas Metálicas/toxicidade , Testes de Sensibilidade Microbiana , Tamanho da Partícula , Extratos Vegetais/metabolismo , Folhas de Planta/química , Folhas de Planta/metabolismo , alfa-Amilases/antagonistas & inibidores , alfa-Amilases/metabolismo
4.
Chem Commun (Camb) ; 55(61): 9039-9042, 2019 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-31292589
5.
J Photochem Photobiol B ; 197: 111556, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31326842

RESUMO

Facile green synthesis of copper nanoparticles from different biological procedures has been indicated, but among all, biosynthesis of copper nanoparticles from medicinal plants is considered as the most suitable method. The use of medicinal plant material increases the therapeutical effects of copper nanoparticles. The aim of this study was green synthesis of copper nanoparticles from aqueous extract of Falcaria vulgaris leaf (CuNPs) and assessment of their cytotoxicity, antioxidant, antifungal, antibacterial, and cutaneous wound healing properties. These nanoparticles were characterized by X-ray diffraction (XRD), fourier-transform infrared spectroscopy (FT-IR), ultraviolet-visible spectroscopy (UV), transmission electron microscopy (TEM), and field emission scanning electron microscopy (FE-SEM) analysis. The synthesized CuNPs had great cell viability dose-dependently (Investigating the effect of the CuNPs on human umbilical vein endothelial cell (HUVEC) line) and indicated this method was nontoxic. Also, 2,2-diphenyl-1-picrylhydrazyl (DPPH) test was done to assess the antioxidant activities, which indicated similar antioxidant potentials for CuNPs and butylated hydroxytoluene. In part of cutaneous wound healing property of CuNPs, after creating the cutaneous wound, the rats were randomly divided into six groups: treatment with 0.2% CuNPs ointment, treatment with 0.2% CuSO4 ointment, treatment with 0.2% F. vulgaris ointment, treatment with 3% tetracycline ointment, treatment with Eucerin basal ointment, and untreated control. These groups were treated for 10 days. Treatment with CuNPs ointment remarkably increased (p ≤ .01) the wound contracture, vessel, hexosamine, hydroxyl proline, hexuronic acid, fibrocyte, and fibrocytes/fibroblast rate and substantially reduced (p ≤ .01) the wound area, total cells, neutrophil, and lymphocyte compared to other groups. In antibacterial and antifungal parts of this research, the concentration of CuNPs with minimum dilution and no turbidity was considered minimum inhibitory concentration (MIC). To determine minimum fungicidal concentration (MFC) and minimum bactericidal concentration (MBC), 60 µL MIC and three preceding chambers were cultured on Sabouraud Dextrose Agar and Muller Hinton Agar, respectively. The minimum concentration with no fungal and bacterial growth were considered MFC and MBC, respectively. CuNPs inhibited the growth of all fungi at 2-4 mg/mL concentrations and removed them at 4-8 mg/mL concentrations (p ≤ .01). In case of antibacterial effects of CuNPs, they inhibited the growth of all bacteria at 2-8 mg/mL concentrations and removed them at 4-16 mg/mL concentrations (p ≤ .01). The results of XRD, FT-IR, UV, TEM, and FE-SEM confirm that the aqueous extract of F. vulgaris leaf can be used to yield copper nanoparticles with notable amount of antioxidant, antifungal, antibacterial, and cutaneous wound healing potentials without any cytotoxicity. Further clinical trials are necessary for confirmation these therapeutical effects of CuNPs in human.


Assuntos
Apiaceae/química , Cobre/química , Nanopartículas Metálicas/química , Extratos Vegetais/química , Animais , Antibacterianos/síntese química , Antibacterianos/química , Antibacterianos/farmacologia , Antifúngicos/síntese química , Antifúngicos/química , Antifúngicos/farmacologia , Antioxidantes/química , Apiaceae/metabolismo , Candida/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Química Verde , Células Endoteliais da Veia Umbilical Humana , Humanos , Masculino , Nanopartículas Metálicas/toxicidade , Testes de Sensibilidade Microbiana , Folhas de Planta/química , Folhas de Planta/metabolismo , Ratos , Pele/efeitos dos fármacos , Pele/patologia , Cicatrização/efeitos dos fármacos
6.
J Photochem Photobiol B ; 197: 111536, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31326846

RESUMO

The latent utilization of biomaterials that are osteo-conducive in the advancement of healing bone fracture has fascinated extensive consideration. This work includes the synthesis of silver nanoparticles (AgNPs) with the help of a Bauhinia acuminate plant flower extract through an ecofriendly synthetic process without any use of harmful reductants. In the fabrication of AgNPs, Bauhinia acuminate plant flower extract bio constituents acts as both stabilizing and reducing agent. The studies of Fourier transform infrared (FTIR) and X-ray diffraction (XRD) techniques confirmed the formation of AgNPS. TEM images revealed that AgNPs are uniform with average particle size of 17 nm. Further, this work explored if silver nanoparticles (AgNPs) might endorse the osteogenesis and proliferation of mesenchymal stem cells (MSCs) and advance the curing of bone fractures. We also exhibited that the prepared AgNPs could promote the in -vitro osteogenic differentiation and proliferation of MSCs'. Also, the prepared AgNps could stimulate the proliferation of mMSCs at specific concentrations of 6-20 µM. Further, cell viability studies showed that AgNPs exhibited no reduction in mouse mesenchymal stem cell viability at <4 µM. Further, these results indicated the induction effects of AgNPs on osteogenic differentiation and proliferation on MSCs, as well as the advancement of meniscus injury healing.


Assuntos
Bauhinia/química , Nanopartículas Metálicas/química , Osteogênese , Extratos Vegetais/química , Prata/química , Animais , Bauhinia/metabolismo , Diferenciação Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Flores/química , Flores/metabolismo , Consolidação da Fratura/efeitos dos fármacos , Química Verde , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Células-Tronco Mesenquimais/metabolismo , Nanopartículas Metálicas/toxicidade , Camundongos , Microscopia Eletrônica de Transmissão , Osteogênese/efeitos dos fármacos , Espectroscopia de Infravermelho com Transformada de Fourier
7.
Int J Nanomedicine ; 14: 4723-4739, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31308655

RESUMO

Background: Much consideration has been paid to the toxicological assessment of nanoparticles prior to clinical and biological applications. While in vitro studies have been expanding continually, in vivo investigations of nanoparticles have not developed a cohesive structure. This study aimed to assess the acute toxicity of different concentrations of chitosan-coated silver nanoparticles (Ch-AgNPs) in main organs, including liver, kidneys, and spleen. Materials and methods: Twenty-eight male albino rats were used and divided into 4 groups (n=7). Group 1 was kept as a negative control group. Groups 2, 3, and 4 were treated intraperitoneally with Ch-AgNPs each day for 14 days at doses of 50, 25, and 10 mg/kg body weight (bwt) respectively. Histopathological, morphometric and immunohistochemical studies were performed as well as oxidative stress evaluations, and specific functional examinations for each organ were elucidated. Results: It was revealed that Ch-AgNPs induced dose-dependent toxicity, and the repeated dosing of rats with 50 mg/kg Ch-AgNPs induced severe toxicities. Histopathological examination showed congestion, hemorrhage, cellular degeneration, apoptosis and necrosis in hepatic and renal tissue as well as lymphocytic depletion with increasing tangible macrophages in the spleen. The highest levels of malondialdehyde, alanine aminotransferase, aspartate aminotransferase (MDA, ALT, AST) and the lowest levels of reduced glutathione, immunoglobulin G, M and total protein (GSH, IgG, IgM, TP) were observed in this group. On the other hand, repeated dosing with 25 mg/kg induced mild to moderate disturbance in the previous parameters, while there was no significant difference in results of pathological examination and biochemical tests between the control group and those treated with 10 mg/kg bwt Ch-AgNPs. Conclusion: Chitosan-coated silver nanoparticles induce dose-dependent adverse effects on rats.


Assuntos
Quitosana/química , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Nanopartículas Metálicas/toxicidade , Prata/toxicidade , Alanina Transaminase/sangue , Animais , Aspartato Aminotransferases/sangue , Nitrogênio da Ureia Sanguínea , Caspase 3/metabolismo , Creatinina/sangue , Glutationa/metabolismo , Rim/efeitos dos fármacos , Fígado/efeitos dos fármacos , Fígado/patologia , Masculino , Malondialdeído/metabolismo , Nanopartículas Metálicas/ultraestrutura , Estresse Oxidativo/efeitos dos fármacos , Antígeno Nuclear de Célula em Proliferação/metabolismo , Ratos Wistar , Baço/efeitos dos fármacos , Baço/patologia
8.
Int J Nanomedicine ; 14: 4801-4816, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31308659

RESUMO

Background: Silver nanoparticles (AgNPs) inhibit the proliferation of various fungi; however, their mechanisms of action remain poorly understood. To better understand the inhibitory mechanisms, we focused on the early events elicited by 5 nm AgNPs in pathogenic Candida albicans and non-pathogenic Saccharomyces cerevisiae. Methods: The effect of 5 nm and 100 nm AgNPs on fungus cell proliferation was analyzed by growth kinetics monitoring and spot assay. We examined cell cycle progression, reactive oxygen species (ROS) production, and cell death using flow cytometry. Glucose uptake was assessed using tritium-labeled 2-deoxyglucose. Results: The growth of both C. albicans and S. cerevisiae was suppressed by treatment with 5 nm AgNPs but not with 100 nm AgNPs. In addition, 5 nm AgNPs induced cell cycle arrest and a reduction in glucose uptake in both fungi after 30 minutes of culture in a dose-dependent manner (P<0.05). However, in C. albicans only, an increase in ROS production was detected after exposure to 5 nm AgNPs. Concordantly, an ROS scavenger blocked the effect of 5 nm AgNPs on the cell cycle and glucose uptake in C. albicans only. Furthermore, the growth-inhibition effect of 5 nm AgNPs was not greater in S. cerevisiae mutant strains deficient in oxidative stress response genes than it was in wild type. Finally, 5 nm AgNPs together with a glycolysis inhibitor, 3-bromopyruvate, synergistically enhanced cell death in C. albicans (P<0.05) but not in S. cerevisiae. Conclusion: AgNPs exhibit antifungal activity in a manner that may or may not be ROS dependent, according to the fungal species. The combination of AgNPs with 3-bromopyruvate may be more useful against infection with C. albicans.


Assuntos
Candida albicans/citologia , Ciclo Celular/efeitos dos fármacos , Nanopartículas Metálicas/toxicidade , Piruvatos/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Saccharomyces cerevisiae/citologia , Prata/farmacologia , Antifúngicos/farmacologia , Candida albicans/efeitos dos fármacos , Candida albicans/crescimento & desenvolvimento , Morte Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Parede Celular/efeitos dos fármacos , Parede Celular/genética , Depuradores de Radicais Livres/farmacologia , Fase G1/efeitos dos fármacos , Genes Fúngicos , Glucose/metabolismo , Glicólise/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Estresse Oxidativo/genética , Saccharomyces cerevisiae/efeitos dos fármacos , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/crescimento & desenvolvimento
9.
J Phys Chem Lett ; 10(15): 4185-4191, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31295998

RESUMO

The treatment of massive bone defects is still a significant challenge for orthopedists. Here we have engineered synthetic porous AuPd alloy nanoparticles (pAuPds) as a hyperthermia agent for in situ bone regeneration through photothermal therapy (PTT). After being swallowed by cells, pAuPds produced a mild localized heat (MLH) (40-43 °C) under the irradiation of a near-infrared laser, which can greatly accelerate cell proliferation and bone regeneration. Almost 97% of the cranial defect area (8 mm in diameter) was covered by the newly formed bone after 6 weeks of PTT. RNA sequencing analysis was used to obtain insight into the molecular mechanism of the MLH on cell proliferation and bone formation. These results demonstrated that the Wnt signaling pathway was involved in the MLH. This Letter provides a unique strategy with mild heat stimulation and high efficiency for in situ bone regeneration.


Assuntos
Ligas/química , Regeneração Óssea , Ouro/química , Nanopartículas Metálicas/química , Paládio/química , Animais , Materiais Biocompatíveis/química , Linhagem Celular , Proliferação de Células , Sobrevivência Celular , Hipertermia Induzida , Raios Infravermelhos , Nanopartículas Metálicas/administração & dosagem , Nanopartículas Metálicas/toxicidade , Camundongos , Fototerapia , Porosidade , Ratos , Crânio/patologia
10.
Environ Monit Assess ; 191(8): 497, 2019 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-31312907

RESUMO

A few studies had determined the effects of silver nanoparticles on the development of Drosophila melanogaster. However, none had addressed its genotoxic effects on specific larval cells of the fly in details. This study was conducted to determine the effects of silver nanoparticle on the development of D. melanogaster with simultaneous evaluation of its genotoxic potential on specific larval cell types that play important roles in immunological defenses as well as growth and development. Five male and five female flies were maintained in standard Drosophila melanogaster culture medium containing varying concentrations of silver nanoparticles, i.e., 25, 50, 100, 200, and 300 mg/l with control culture medium containing no nanoparticle. Total time needed for stage-specific development, population yield, and genotoxic effects on third instar larval polytene chromosomes, hemocytes, and neuroblasts was determined. Body pigmentation of pupae and young adults was examined visually. In comparison with control, silver nanoparticles dose dependently inhibited the metamororphosis and population yields of pupae and young adults of Drosophila melanogaster. Every concentration of the nanoparticles inhibited pupa to adult conversion, with huge reduction under the influence of nanoparticle concentration of 100 mg/ml and above. Developmental inhibition was accompanied by dose-dependent and significant structural aberrations of larval polytene chromosomes and deformities of hemocytes and neuroblasts. Pupae and young adults also exhibited gradual discoloration of body with the increase in exposure to nanoparticle concentration.


Assuntos
Dano ao DNA , Drosophila melanogaster/efeitos dos fármacos , Larva/efeitos dos fármacos , Nanopartículas Metálicas/toxicidade , Células-Tronco Neurais/efeitos dos fármacos , Prata/toxicidade , Animais , Relação Dose-Resposta a Droga , Drosophila melanogaster/genética , Drosophila melanogaster/crescimento & desenvolvimento , Monitoramento Ambiental , Feminino , Larva/genética , Larva/crescimento & desenvolvimento , Masculino , Pupa/efeitos dos fármacos , Pupa/genética , Pupa/crescimento & desenvolvimento
11.
Ecotoxicol Environ Saf ; 181: 60-68, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31174108

RESUMO

The widespread use of microplastics and nanomaterials resulting in environmental contamination is of high concern. Microplastics have been found to modulate the toxicity of other environmental contaminants. Thus, the hypothesis that microplastics increase the toxicity of gold nanoparticles to the marine microalgae Tetraselmis chuii was tested. In a laboratory bioassay, T. chuii cultures were exposed for 96 h to ∼5 nm diameter gold nanoparticles (AuNP) and to virgin 1-5 µm diameter microplastics (MP), alone and in mixture. The treatments were: control; citrate-control; AuNP alone (0.1, 0.3 and 3 mg/L); MP alone (0.3, 0.9 and 4 mg/L) and mixture of the two substances in three different concentrations (0.1 mg/L AuNP + 0.3 mg/L MP; 0.3 mg/L AuNP + 0.9 mg/L MP; 3 mg/l AuNP + 4 mg/L MP). The effect criterion was the inhibition of the average specific growth rate. AuNP alone and MP alone did not cause significant decrease of T. chui average specific growth rate up to 3 mg/L and 4 mg/L, respectively. The mixture containing 3 mg/L AuNP + 4 mg/L MP significantly reduced the average specific growth rate of the microalgae. Therefore, this mixture was more toxic to T. chuii than its components individually. Overall, the results of the present study indicated that the MP and AuNP tested have a relatively low toxicity to T. chuii, but the toxicity increases when they are in mixtures containing high concentrations of both substances. These proof-of-concept findings stress the need of more research on the toxicity of mixtures containing microplastics and nanomaterials.


Assuntos
Clorófitas/efeitos dos fármacos , Ouro/toxicidade , Nanopartículas Metálicas/toxicidade , Microalgas/efeitos dos fármacos , Plásticos/toxicidade , Poluentes Químicos da Água/toxicidade , Bioensaio , Modelos Teóricos
12.
J Photochem Photobiol B ; 197: 111531, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31212244

RESUMO

Environment friendly methods for the synthesis of copper nanoparticles have become a valuable trend in the current scenario. The utilization of phytochemicals from plant extracts has become a unique technology for the synthesis of nanoparticles, as they possess dual nature of reducing and capping agents to the nanoparticles. In the present investigation we have synthesized copper nanoparticles (CuNPs) using a rare medicinal plant Cissus arnotiana and evaluated their antibacterial activity against gram negative and gram positive bacteria. The morphology and characterization of the synthesized CuNPs were studied and done using UV-Visible spectroscopy at a wavelength range of 350-380 nm. XRD studies were performed for analyzing the crystalline nature; SEM and TEM for evaluating the spherical shape within the size range of 60-90 nm and AFM was performed to check the surface roughness. The biosynthesized CuNPs showed better antibacterial activity against the gram-negative bacteria, E. coli with an inhibition zone of 22.20 ±â€¯0.16 mm at 75 µg/ml. The antioxidant property observed was comparatively equal with the standard antioxidant agent ascorbic acid at a maximum concentration of 40 µg/ ml. This is the first study reported on C. arnotiana mediated biosynthesis of copper nanoparticles, where we believe that the findings can pave way for a new direction in the field of nanotechnology and nanomedicine where there is a significant potential for antibacterial and antioxidant activities. We predict that, these could lead to an exponential increase in the field of biomedical applications, with the utilization of green synthesized CuNPs, due to its remarkable properties. The highest antibacterial property was observed with gram-negative strains mainly, E. coli, due to its thin peptidoglycan layer and electrostatic interactions between the bacterial cell wall and CuNPs surfaces. Hence, CuNPs can be potent therapeutic agents in several biomedical applications, which are yet to be explored in the near future.


Assuntos
Antibacterianos/química , Antioxidantes/química , Cissus/química , Cobre/química , Nanopartículas Metálicas/química , Extratos Vegetais/química , Antibacterianos/síntese química , Antibacterianos/farmacologia , Cissus/metabolismo , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Química Verde , Nanopartículas Metálicas/toxicidade , Testes de Sensibilidade Microbiana , Eletricidade Estática
13.
J Photochem Photobiol B ; 197: 111529, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31220803

RESUMO

The therapeutic molecules recovered from the marine biological origin are widely used for the treatment of diverse levels of infections caused by microbial pathogens. In addition, the eco-friendly preparations of nanomaterials together with the secondary metabolites' producing active microbial strains effectively suppress the spreading of the pathogenic bacteria. Considering their importance, the present study evaluated the environmental friendly synthesis of Silver nitrate nanomaterials (SNM) from the active marine Streptomyces strain Al-Dhabi-91 isolated from the Dammam region of Saudi Arabia. The obtained SNM was chemically characterized by various spectroscopic techniques such as UV, XRD, FTIR, SEM, TEM and EDAX; and its biological applications such as antimicrobial properties and antioxidant potential were recorded by DPPH methods. Biochemical and micromorphological studies together with the molecular techniques confirmed that the isolate Al-Dhabi-91 belonged to Streptomyces species. The characterization techniques confirmed that the UV spectrum showed maximum absorption peak at 305 nm indicating the plasmodium characteristics. SEM and TEM analyses evidenced 5-2 nm which are agglomerated, cool to form porous asymmetrical networks. Additionally, the FTIR spectrum showed maximum peak at 1194 cm-1 and 1394 cm-1, confirming the presence of aromatic CH bending and aromatic CC bending in the SNM. SNM exhibited prolific antibacterial activity against Gram negative pathogens, K. pneumoniae (28.33 mm) and E. coli (21.66 mm) respectively. The MIC values of SNM were significant with respect to E. faecalis (125 µg/ml), S. aureus (250 µg/ml), P. aeruginosa (125 µg/ml), K. pneumoniae (500 µg/ml) and E. coli (250 µg/ml) respectively. In addition, the antioxidant potential of the SNM was another value added importance. Especially 50 µg/ml of the nanoparticles showed 33% antioxidant potential; similarly in nitric oxide radical inhibition assay the concentration of 50 µg/ml nanoparticles showed 33% of inhibition potential. Overall, the eco-friendly synthesis of SNM from the marine Streptomyces strain Al-Dhabi-91 was an ideal active source for the treatment of infectious disease and health associated disorders.


Assuntos
Anti-Infecciosos/química , Antioxidantes/química , Sedimentos Geológicos/microbiologia , Nanopartículas Metálicas/química , Prata/química , Streptomyces/química , Anti-Infecciosos/farmacologia , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Química Verde , Nanopartículas Metálicas/toxicidade , Testes de Sensibilidade Microbiana , Filogenia , Arábia Saudita , Streptomyces/classificação , Streptomyces/isolamento & purificação
14.
J Photochem Photobiol B ; 197: 111519, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31228688

RESUMO

Gold nanoparticles of comparable size were synthetized using honey mediated green method (AuNPs@honey) and citrate mediated Turkevich method (AuNPs@citrate). Their colloidal behavior in two cell media DMEM and RPMI, both supplemented with 10% FBS, was systematically investigated with different characterization techniques in order to evidence how the composition of the media influences their stability and the development of protein/NP complex. We revealed the formation of the protein corona which individually covers the nanoparticles in RPMI media, like a dielectric spacer according to UV-Vis spectroscopy, while DMEM promotes more abundant agglomerations, clustering together the nanoparticles, according to TEM investigations. In order to evaluate the biological impact of nanoparticles, B16 melanoma and L929 mouse fibroblasts cells were used to carry out the viability assays. Generally, the L929 cells were more sensitive than B16 cells to the presence of gold nanoparticles. Measurements of cell viability, proliferation and apoptotic activities of B16 cells indicated that the effects induced by AuNPs@honey were slightly similar to those induced by AuNPs@citrate, however, the toxic response improved in the L929 fibroblast cells following the treatment with AuNPs@honey within the same concentration range from 1 µg/ml to 15 µg/ml for 48 h. Results showed that honey mediated synthesis generates nanoparticles with reduced toxicity trends depending on the cell type, concentration of nanoparticles and exposure time toward various biomedical applications.


Assuntos
Citratos/química , Ouro/química , Mel/análise , Nanopartículas Metálicas/química , Animais , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Nanopartículas Metálicas/toxicidade , Camundongos , Tamanho da Partícula , Espectroscopia de Infravermelho com Transformada de Fourier , Ressonância de Plasmônio de Superfície
15.
Bratisl Lek Listy ; 120(6): 397-409, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31223019

RESUMO

Copper is a biogenic metal having multiple functions in basic processes in organisms and it is common in all kingdoms of life. Limited intake of copper is a problem; however, doses of copper exceeding the recommended alimentary source are problematic as well and toxicity is soon manifested. Impact of copper nanoparticles on human health is another serious issue taken into consideration in this review. Regarding to copper toxicity, neurodegenerative disorders including Alzheimer and Parkinson diseases are suspected to be linked to copper toxicity or copper can contribute to their progression. Wilson and Menke diseases are also described as examples of copper intolerance. This paper is focused on the description, literature survey and discussion of the current knowledge about copper and copper nanoparticles toxicity and their involvement in various pathological processes (Tab. 6, Fig. 2, Ref. 171). Keywords: reactive oxygen species; Alzheimer disease; acetylcholinesterase; copper; Fenton reaction; disorder; heavy metal; pollution; nanoparticle.


Assuntos
Cobre , Nanopartículas Metálicas , Doença de Alzheimer , Cobre/toxicidade , Humanos , Nanopartículas Metálicas/toxicidade , Doença de Parkinson , Espécies Reativas de Oxigênio
16.
Aquat Toxicol ; 213: 105221, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31207537

RESUMO

Engineered nanomaterials (ENMs) tend to precipitate in saline waters so the majority of aquatic toxicity studies have focused on freshwaters, where bioavailability is presumed to be higher. Recent studies have illustrated that some ENM formulations are bioavailable and bioactive in salt water and that their effects are more pronounced at the physiological than biochemical level. These findings raise concerns regarding the effects of ENMs on marine organisms. Therefore, our goal was to characterize the effects of polyvinylpyrolidone-functionalized silver ENMs (nAg) on aerobic performance in the killifish (Fundulus heteroclitus), a common euryhaline teleost. Fish were exposed to 80 µg L-1 of 5 nm nAg for 48 h in brackish water (12 ppt) and routine (MO2min) and maximum (MO2max) rates of oxygen consumption were quantified. Silver dissolution was minimal and nAg remained well dispersed in brackish water, with a hydrodynamic diameter of 21.0 nm, compared to 19.3 in freshwater. Both MO2min and MO2max were significantly lower (by 53 and 30%, respectively) in killifish exposed to nAg and a reduction in MO2 variability suggested spontaneous activity was suppressed. Neither gill Na+/K+-ATPase activity, nor various other biochemical markers were affected by nAg exposure. The results illustrate that a common ENM formulation is bioactive in salt water and, as in previous studies on functionalized copper ENMs, that effects are more pronounced at the whole animal than the biochemical level.


Assuntos
Água Doce , Fundulidae/fisiologia , Nanopartículas Metálicas/toxicidade , Prata/toxicidade , Testes de Toxicidade , Acetilcolinesterase/metabolismo , Aerobiose , Animais , Metabolismo Basal/efeitos dos fármacos , Metabolismo Energético/efeitos dos fármacos , Fundulidae/sangue , Brânquias/efeitos dos fármacos , Brânquias/ultraestrutura , Hidrocortisona/sangue , Fígado/metabolismo , Nanopartículas Metálicas/ultraestrutura , Consumo de Oxigênio/efeitos dos fármacos , ATPase Trocadora de Sódio-Potássio/metabolismo , Poluentes Químicos da Água/toxicidade
17.
Sci Total Environ ; 685: 19-27, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31170592

RESUMO

Few data are available about the effect of dimethylated forms (DMA) on aquatic organisms. As rarely a contaminant occurs alone, studies evaluating the combined effect of different contaminants in aquatic organisms are needed. In fact, the presence of nanomaterials, such as titanium dioxide nanoparticles (nTiO2), in the aquatic environment is now a reality due to its intensive production and use. So, this study evaluated the toxicological effects of DMA in an acute exposure condition and considered the potential influence of nTiO2 on the effects induced by DMA in the polychaete, Laeonereis culveri. The animals were exposed over 48 h to DMA (50 and 500 µg/l) alone or in combination with nTiO2 (1 mg/l). Biochemical parameters such as concentration of reactive oxygen species (ROS), glutathione-S-transferase (GST) activity, levels of reduced glutathione levels (GSH) and macromolecular (lipid and DNA) damage were evaluated, as well the DNA repair system. In addition, the accumulation of total As and the chemical speciation of the metalloid in the organisms was determined. The results showed that: (1) only the group exposed to 500 µg of DMA/l accumulated As and when co-exposed to nTiO2, this accumulation was not observed. (2) The levels of ROS increased in the group exposed to 50 µg/l of DMA alone and the effect was reversed when this group was co-exposed to nTiO2 (3) None of the treatments showed altered GST activity or GSH levels. (4) All groups that received nTiO2 (alone or in combination with DMA) showed lipid peroxidation. (5) The exposure to DMA (both concentrations) alone or in combination with nTiO2 induced DNA damage in L. culveri. These results showed that DMA exhibits a genotoxic effect and that co-exposure to nTiO2 had an influence on its toxicity. So the occurrence of both contaminants simultaneously can represent a threat to aquatic biota.


Assuntos
Ácido Cacodílico/toxicidade , Nanopartículas Metálicas/toxicidade , Poliquetos/fisiologia , Titânio/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Glutationa/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Estresse Oxidativo
18.
Environ Sci Pollut Res Int ; 26(22): 22529-22550, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31161543

RESUMO

Widespread application of silver nanoparticles (AgNPs), due to their antibacterial and antifungal properties, increases their release into the environment and potential detrimental impact on living organisms. Plants may serve as a potential pathway for AgNPs bioaccumulation and a route into the food chain, hence investigation of AgNP phytotoxic effects are of particular importance. Since proteins are directly involved in stress response, studies of their abundance changes can help elucidate the mechanism of the AgNP-mediated phytotoxicity. In this study, we investigated proteomic changes in tobacco (Nicotiana tabacum) exposed to AgNPs and ionic silver (AgNO3). A high overlap of differently abundant proteins was found in root after exposure to both treatments, while in leaf, almost a half of the proteins exhibited different abundance level between treatments, indicating tissue-specific responses. Majority of the identified proteins were down-regulated in both tissues after exposure to either AgNPs or AgNO3; in roots, the most affected proteins were those involved in response to abiotic and biotic stimuli and oxidative stress, while in leaf, both treatments had the most prominent effect on photosynthesis-related proteins. However, since AgNPs induced higher suppression of protein abundance than AgNO3, we conclude that AgNP effects can, at least partially, be attributed to nanoparticle form.


Assuntos
Nanopartículas Metálicas/toxicidade , Prata/toxicidade , Tabaco/fisiologia , Íons , Estresse Oxidativo/efeitos dos fármacos , Folhas de Planta/metabolismo , Proteoma/metabolismo , Proteômica , Nitrato de Prata/toxicidade , Tabaco/metabolismo
19.
Chemosphere ; 233: 579-589, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31195263

RESUMO

Complex interactions have been established between nanoparticles (NPs) and heavy metals in real environments. Herein we used zebrafish embryos to investigate the influence of titanium dioxide NPs (n-TiO2) on the uptake, bioconcentration, and depuration, and toxicity of Pb. The formation of n-TiO2-Pb complexes was confirmed in an exposure suspension. An increase in Pb bioconcentration was observed in zebrafish embryos upon co-exposure to n-TiO2 and Pb; moreover, n-TiO2-Pb complexes could be found in the embryos, indicating the bioavailability of NPs. However, there was no difference in the depuration rates of Pb in the presence of n-TiO2. Metallothionein (MT) content was significantly increased upon exposure to Pb alone, and the content significantly increased even further upon co-exposure. A downregulation in the expression levels of the neurodevelopment-related genes gfap, syn2α, and elavl3 was observed in the embryos, and we also noted a reduction in the swimming speed of and the total distance traveled by the larvae. To summarize, our results indicate that n-TiO2 can act as an effective carrier of Pb to enhance its uptake, bioavailability, and toxicity in zebrafish embryos.


Assuntos
Embrião não Mamífero/fisiologia , Chumbo/toxicidade , Nanopartículas Metálicas/toxicidade , Titânio/toxicidade , Poluentes Químicos da Água/toxicidade , Peixe-Zebra/embriologia , Animais , Disponibilidade Biológica , Embrião não Mamífero/efeitos dos fármacos , Embrião não Mamífero/metabolismo , Larva/metabolismo , Metalotioneína/metabolismo , Nanopartículas/toxicidade , Peixe-Zebra/metabolismo
20.
Aquat Toxicol ; 212: 47-53, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31071656

RESUMO

The increasing production of engineered inorganic nanoparticles (EINPs) elevates their release into aquatic ecosystems raising concerns about associated environmental risks. Numerous investigations indicate sediments as the final sink, facilitating the exposure of benthic species to EINPs. Although reports of sub-lethal EINP effects on benthic species are increasing, the importance of exposure pathways (either waterborne or dietary) is poorly understood. This study investigates the influence of two EINPs, namely titanium dioxide (nTiO2) and silver (nAg), on the benthic model organism Gammarus fossarum specifically addressing the relative relevance of these pathways. For each type of EINP an individual 30-day long bioassay was conducted, applying a two-factorial test design. The factors include the presence or absence of the EINPs (nTiO2: ∼80 nm, 4 mg/L or nAg: ∼30 nm, 0.125 mg/L; n = 30) in the water phase (waterborne), combined with a preceding 6-day long aging of their diet (black alder leaves) also in presence or absence of the EINPs (dietary). Response variables were mortality, food consumption, feces production and energy assimilation. Additionally, the physiological fitness was examined using lipid content and dry weight of the organisms as measures. Results revealed a significantly reduced energy assimilation (up to ∼30%) in G. fossarum induced by waterborne exposure towards nTiO2. In contrast, the dietary exposure towards nAg significantly increased the organisms' energy assimilation (up to ∼50%). Hence, exposure pathway dependent effects of EINPs cannot be generalized and remain particle specific resting upon their intrinsic properties affecting their potential to interact with the surrounding environment. As a result of the different properties of the EINPs used in this study, we clearly demonstrated variations in type and direction of observed effects in G. fossarum. The results of the present study are thus supporting current approaches for nano-specific grouping that might enable an enhanced accuracy in predicting EINP effects facilitating their environmental risk assessment.


Assuntos
Anfípodes/efeitos dos fármacos , Exposição Ambiental , Nanopartículas Metálicas/toxicidade , Prata/toxicidade , Titânio/toxicidade , Animais , Biomassa , Metabolismo Energético/efeitos dos fármacos , Fezes , Comportamento Alimentar/efeitos dos fármacos , Lipídeos/análise , Tamanho da Partícula , Folhas de Planta/metabolismo , Poluentes Químicos da Água/toxicidade
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