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1.
Viruses ; 15(10)2023 09 29.
Artículo en Inglés | MEDLINE | ID: mdl-37896801

RESUMEN

(1) Background: Epigallocatechin gallate (EGCG) has been recognized as a flavonoid showing antiviral activity against various types of DNA and RNA viruses. In this work, we tested if EGCG-modified silver nanoparticles (EGCG-AgNPs) can become novel microbicides with additional adjuvant properties to treat herpes infections. (2) Methods: The anti-HSV and cytotoxic activities of EGCG-AgNPs were tested in human HaCaT and VK-2-E6/E7 keratinocytes. HSV-1/2 titers and immune responses after treatment with EGCG-AgNPs were tested in murine models of intranasal HSV-1 infection and genital HSV-2 infection. (3) Results: EGCG-AgNPs inhibited attachment and entry of HSV-1 and HSV-2 in human HaCaT and VK-2-E6/E7 keratinocytes much better than EGCG at the same concentration. Infected mice treated intranasally (HSV-1) or intravaginally (HSV-2) with EGCG-AgNPs showed lower virus titers in comparison to treatment with EGCG alone. After EGCG-AgNPs treatment, mucosal tissues showed a significant infiltration in dendritic cells and monocytes in comparison to NaCl-treated group, followed by significantly better infiltration of CD8+ T cells, NK cells and increased expression of IFN-α, IFN-γ, CXCL9 and CXCL10. (4) Conclusions: Our findings show that EGCG-AgNPs can become an effective novel antiviral microbicide with adjuvant properties to be applied upon the mucosal tissues.


Asunto(s)
Herpes Genital , Herpes Simple , Herpesvirus Humano 1 , Nanopartículas del Metal , Animales , Humanos , Ratones , Plata/farmacología , Herpes Simple/tratamiento farmacológico , Herpes Genital/tratamiento farmacológico , Herpesvirus Humano 2 , Antivirales/farmacología
2.
Materials (Basel) ; 16(14)2023 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-37512387

RESUMEN

The described research aimed to develop the properties of the conductive composite /poly(3,4-ethylenedioxy-thiophene-poly(4-lithium styrenesulfonic acid)/chitosan-AuNPs-glutaraldehyde/ (/PEDOT-PSSLi/chit-AuNPs-GA/) and to develop an electrochemical enzyme sensor based on this composite material and glassy carbon electrodes (GCEs). The composite was created via electrochemical production of an /EDOT-PSSLi/ layer on a glassy carbon electrode (GCE). This layer was covered with a glutaraldehyde cross-linked chitosan and doped with AuNPs. The influence of AuNPs on the increase in the electrical conductivity of the chitosan layers and on facilitating the oxidation of polyphenols in these layers was demonstrated. The enzymatic sensor was obtained via immobilization of the laccase on the surface of the composite, with glutaraldehyde as the linker. The investigation of the surface morphology of the GCE/PEDOT-PSSLi/chit-AuNPs-GA/Laccase sensor was carried out using SEM and AFM microscopy. Using EDS and Raman spectroscopy, AuNPs were detected in the chitosan layer and in the laccase on the surface of the sensor. Polyphenols were determined using differential pulse voltammetry. The biosensor exhibited catalytic activity toward the oxidation of polyphenols. It has been shown that laccase is regenerated through direct electron transfer between the sensor and the enzyme. The results of the DPV tests showed that the developed sensor can be used for the determination of polyphenols. The peak current was linearly proportional to the concentrations of catechol in the range of 2-90 µM, with a limit of detection (LOD) of 1.7 µM; to those of caffeic acid in the range of 2-90 µM, LOD = 1.9 µM; and to those of gallic acid in the range 2-18 µM, LOD = 1.7 µM. Finally, the research conducted in order to determine gallic acid in a natural sample, for which white wine was used, was described.

3.
Int J Mol Sci ; 23(21)2022 Oct 28.
Artículo en Inglés | MEDLINE | ID: mdl-36361890

RESUMEN

Metallic nanoparticles exhibit broad-spectrum activity against bacteria, fungi, and viruses. The antiviral activity of nanoparticles results from the multivalent interactions of nanoparticles with viral surface components, which result from the nanometer size of the material and the presence of functional compounds adsorbed on the nanomaterial surface. A critical step in the virus infection process is docking and entry of the virus into the host cell. This stage of the infection can be influenced by functional nanomaterials that exhibit high affinity to the virus surface and hence can disrupt the infection process. The affinity of the virus to the nanomaterial surface can be tuned by the specific surface functionalization of the nanomaterial. The main purpose of this work was to determine the influence of the ligand type present on nanomaterial on the antiviral properties against herpes simplex virus type 1 and 2. We investigated the metallic nanoparticles (gold and silver) with different sizes (5 nm and 30 nm), coated either with polyphenol (tannic acid) or sulfonates (ligands with terminated sulfonate groups). We found that the antiviral activity of nano-conjugates depends significantly on the ligand type present on the nanoparticle surface.


Asunto(s)
Herpesvirus Humano 1 , Nanopartículas del Metal , Nanopartículas , Polifenoles/farmacología , Ligandos , Antivirales/farmacología , Alcanosulfonatos
4.
Materials (Basel) ; 15(21)2022 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-36363278

RESUMEN

The present paper describes the effect of the concentration of two graphene oxides (with different oxygen content) in the modifier layer on the electrochemical and structural properties of noble metal disk electrodes used as working electrodes in voltammetry. The chemistry of graphene oxides was tested using EDS, FTIR, UV-Vis spectroscopy, and combustion analysis. The structural properties of the obtained modifier layers were examined by means of scanning electron and atomic force microscopy. Cyclic voltammetry was employed for comparative electrochemical studies.

5.
Microorganisms ; 10(11)2022 Oct 31.
Artículo en Inglés | MEDLINE | ID: mdl-36363754

RESUMEN

Neuroinfections caused by herpesviruses, mainly by HHV-1, represent a significant problem for modern medicine due to the small number of therapeutic substances available in the pharmaceutical sector. Furthermore, HHV-1 infection has been linked to neurodegenerative processes such as Alzheimer's disease, which justifies the search for new effective therapies. The development of nanotechnology opens up new possibilities for the treatment of neuroinflammation. Gold and silver nanoparticles are gaining popularity, and the number of clinical trials involving metallic nanoparticles is constantly increasing. This paper reviews the research on gold and silver nanoparticles and their potential use in the treatment of herpesvirus neuroinfection.

6.
Pharmaceutics ; 14(9)2022 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-36145610

RESUMEN

Lactoferrin is an iron-binding glycoprotein with multiple functions in the body. Its activity against a broad spectrum of both DNA and RNA viruses as well as the ability to modulate immune responses have made it of interest in the pharmaceutical and food industries. The mechanisms of its antiviral activity include direct binding to the viruses or its receptors or the upregulation of antiviral responses by the immune system. Recently, much effort has been devoted to the use of nanotechnology in the development of new antivirals. In this review, we focus on describing the antiviral mechanisms of lactoferrin and the possible use of nanotechnology to construct safe and effective new antiviral drugs.

7.
Molecules ; 27(11)2022 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-35684448

RESUMEN

The clinical performance of a dental restoration is strongly influenced by the complex and dynamically-changing oral environment; however, no standard procedure exists to evaluate this lifetime. This research provides an in-depth analysis of the effect of different aging procedures on the flexural strength (FS), diametral tensile strength (DTS) and hardness (HV) of selected dental materials (Resin F, Flow-Art and Arkon). Material structure was evaluated by scanning electron microscopy. It was found that each aging protocol had some influence on the tested properties, with continual erosion and degradation being observed. Greater mechanical degradation was observed for Resin F (neat resin) after the applied aging protocols, suggesting that a resin matrix is more susceptible for degradation. The most aggressive aging protocol was Protocol 5: 0.1 M NaOH, seven days, 60 °C. Further studies on the effect of artificial aging on dental materials should include a study of the thermal and chemical factors. A standardized aging procedure is crucial for improving the resistance of dental resin composite to oral conditions and their clinical performance.


Asunto(s)
Resinas Compuestas , Resinas Compuestas/química , Dureza , Ensayo de Materiales , Microscopía Electrónica de Rastreo , Estrés Mecánico , Propiedades de Superficie , Resistencia a la Tracción
8.
Molecules ; 27(11)2022 Jun 02.
Artículo en Inglés | MEDLINE | ID: mdl-35684515

RESUMEN

At this time, the development of advanced elastic dielectric materials for use in organic devices, particularly in organic field-effect transistors, is of considerable interest to the scientific community. In the present work, flexible poly(dimethylsiloxane) (PDMS) specimens cross-linked by means of ZnCl2-bipyridine coordination with an addition of 0.001 wt. %, 0.0025 wt. %, 0.005 wt. %, 0.04 wt. %, 0.2 wt. %, and 0.4 wt. % of gold nanoparticles (AuNPs) were prepared in order to understand the effect of AuNPs on the electrical properties of the composite materials formed. The broadband dielectric spectroscopy measurements revealed one order of magnitude decrease in loss tangent, compared to the coordinated system, upon an introduction of 0.001 wt. % of AuNPs into the polymeric matrix. An introduction of AuNPs causes damping of conductivity within the low-temperature range investigated. These effects can be explained as a result of trapping the Cl- counter ions by the nanoparticles. The study has shown that even a very low concentration of AuNPs (0.001 wt. %) still brings about effective trapping of Cl- counter anions, therefore improving the dielectric properties of the investigated systems. The modification proposed reveals new perspectives for using AuNPs in polymers cross-linked by metal-ligand coordination systems.


Asunto(s)
Oro , Nanopartículas del Metal , Dimetilpolisiloxanos/química , Oro/química , Ligandos , Nanopartículas del Metal/química , Polímeros/química
9.
Nanomedicine ; 43: 102558, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35390524

RESUMEN

The aim of the study was to investigate in vivo whether the application of immobilized superoxide dismutase (SOD) and catalase (CAT) could enhance DNA repairing systems and reduce level of CPD (cyclobutane pyrimidine dimers) and 6-4PP ((6-4) pyrimidine-pyrimidone photoproducts), and whether the immobilization on gold (AuNPs) and silver (AgNPs) nanoparticles affects the outcome. The study presents secondary analysis of our previous research. Three-day application of SOD and CAT in all forms of solution decreased the levels of CPD and 6-4PP boosted by UV irradiation. The mRNA expression level of the nucleotide excision repair (NER) system genes (XPA, XPC, ERCC1, ERCC2, ERCC3, LIG1) increased after application of immobilized and free enzymes. Increased by UV irradiation, p53 mRNA expression level normalized with the enzyme application. In conclusion, application of free and immobilized antioxidant enzymes accelerates removal of harmful effects of UV radiation in the rat skin by increasing expression level of NER genes.


Asunto(s)
Nanopartículas del Metal , Rayos Ultravioleta , Animales , Antioxidantes , ADN/genética , Daño del ADN , Reparación del ADN , Oro , ARN Mensajero , Ratas , Plata/farmacología , Superóxido Dismutasa/genética , Superóxido Dismutasa/metabolismo
10.
Molecules ; 27(6)2022 Mar 17.
Artículo en Inglés | MEDLINE | ID: mdl-35335318

RESUMEN

New functionalization methods of meta- and para-aramid fabrics with silver nanowires (AgNWs) and two silanes (3-aminopropyltriethoxysilane (APTES)) and diethoxydimethylsilane (DEDMS) were developed: a one-step method (mixture) with AgNWs dispersed in the silane mixture and a two-step method (layer-by-layer) in which the silanes mixture was applied to the previously deposited AgNWs layer. The fabrics were pre-treated in a low-pressure air radio frequency (RF) plasma and subsequently coated with polydopamine. The modified fabrics acquired hydrophobic properties (contact angle ΘW of 112-125°). The surface free energy for both modified fabrics was approximately 29 mJ/m2, while for reference, meta- and para-aramid fabrics have a free energy of 53 mJ/m2 and 40 mJ/m2, respectively. The electrical surface resistance (Rs) was on the order of 102 Ω and 104 Ω for the two-step and one-step method, respectively. The electrical volume resistance (Rv) for both modified fabrics was on the order of 102 Ω. After UV irradiation, the Rs did not change for the two-step method, and for the one-step method, it increased to the order of 1010 Ω. The specific strength values were higher by 71% and 63% for the meta-aramid fabric and by 102% and 110% for the para-aramid fabric for the two-step and one-step method, respectively, compared to the unmodified fabrics after UV radiation.


Asunto(s)
Nanocables , Plata , Interacciones Hidrofóbicas e Hidrofílicas , Silanos , Plata/química , Textiles
11.
Microorganisms ; 10(1)2022 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-35056558

RESUMEN

(1) Background: Lactoferrin has been recognized as a potent inhibitor of human herpetic viruses, such as herpes simplex type 1 (HSV-1) and 2 (HSV-2). In this work, we tested if silver and gold nanoparticles modified with lactoferrin (LF-Ag/AuNPs) can become novel microbicides with additional adjuvant properties to treat genital herpes infection. (2) Methods: The antiviral and cytotoxic activities of LF-Ag/AuNPs were tested in human skin HaCaT and vaginal VK-2-E6/E7 keratinocytes. Viral titers and immune responses after treatment with LF-Ag/AuNPs were tested in murine vaginal HSV-2 infection. (3) Results: LF-Ag/AuNPs inhibited attachment and entry of HSV-2 in human keratinocytes much better than lactoferrin. Furthermore, pretreatment with LF-AgNPs led to protection from infection. Infected mice treated intravaginally with LF-Ag/AuNPs showed lower virus titers in the vaginal tissues and spinal cords in comparison to treatment with lactoferrin. Following treatment, vaginal tissues showed a significant increase in CD8+/granzyme B + T cells, NK cells and dendritic cells in comparison to NaCl-treated group. LF-Ag/AuNPs-treated animals also showed significantly better expression of IFN-γ, CXCL9, CXCL10, and IL-1ß in the vaginal tissues. (4) Conclusions: Our findings show that LF-Ag/AuNPs could become effective novel antiviral microbicides with immune-stimulant properties to be applied upon the mucosal tissues.

12.
RSC Adv ; 11(7): 4174-4185, 2021 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-35424341

RESUMEN

Since silver nanowires (AgNWs) show high infrared reflectance many studies present their applicability as thermal management products for various wearable textiles. However, their use for practical purposes is only partially evaluated, without focusing on improving their low atmospheric and liquid stability. This report describes a new approach for the topic and proposes a facile method of Ag nanowire passivation with a SnO2 layer for high environmental stability and retention of high infrared reflectance. The one-step passivation process of AgNWs was carried out in the presence of sodium stannate in an aqueous solution at 100 °C, and resulted in the formation of core/shell Ag/SnO2 nanowires. This study presents the morphological, chemical, and structural properties of Ag/SnO2NWs formed with a 14 nm thick SnO2 shell, consisting of 7 nm rutile-type crystals, covering the silver metallic core. The optical properties of the AgNWs changed significantly after shell formation, and the longitudinal and transverse modes in the surface plasmon resonance spectrum were red shifted as a result of the surrounding media dielectric constant changes. The passivation process protected the AgNWs from decomposition in air for over 4 months, and from dissolution in a KCN solution at concentrations up to 0.1 wt%. Moreover, the report shows the microwave irradiation effect on the shell synthesis and previously synthesised Ag/SnO2NWs. The post-synthesis irradiation, as well as the SnO2 shell obtained by microwave assistance, did not allow long-term stability to be achieved. The microwave-assisted synthesis process was also not fast enough to inhibit the formation of prismatic silver structures from the nanowires. The Ag/SnO2NWs with a shell obtained by a simple hydrolysis process, apart from showing high infra-red reflectance on the para-aramid fabric, are highly environmentally stable. The presented SnO2 shell preparation method can protect the AgNW's surface from dissolution or decomposition and facilitate the designing of durable smart wearable thermal materials for various conditions.

13.
Parasit Vectors ; 13(1): 624, 2020 Dec 22.
Artículo en Inglés | MEDLINE | ID: mdl-33353560

RESUMEN

BACKGROUND: Free-living amoebae of the genus Acanthamoeba are cosmopolitan, widely distributed protozoans that cause a severe, vision-threatening corneal infection known as Acanthamoeba keratitis (AK). The majority of the increasing number of AK cases are associated with contact lens use. Appropriate eye hygiene and effective contact lens disinfection are crucial in the prevention of AK because of the lack of effective therapies against it. Currently available multipurpose contact lens disinfection systems are not fully effective against Acanthamoeba trophozoites and cysts. There is an urgent need to increase the disinfecting activity of these systems to prevent AK infections. Synthesized nanoparticles (NPs) have been recently studied and proposed as a new generation of anti-microbial agents. It is also known that some plant metabolites, including tannins, have anti-parasitic activity. The aim of this study was to evaluate the anti-amoebic activity and cytotoxicity of tannic acid-modified silver NPs (AgTANPs) conjugated with selected multipurpose contact lens solutions. METHODS: The anti-amoebic activities of pure contact lens care solutions, and NPs conjugated with contact lens care solutions, were examined in vitro by a colorimetric assay based on the oxido-reduction of alamarBlue. The cytotoxicity assays were performed using a fibroblast HS-5 (ATCC CRL-11882) cell line. The results were statistically analysed by ANOVA and Student-Newman-Keuls test using P < 0.05 as the level of statistical significance. RESULTS: We show that the NPs enhance the anti-Acanthamoeba activities of the tested contact lens solutions without increasing their cytotoxicity profiles. The activities are enhanced within the minimal disinfection time recommended by the manufacturers. CONCLUSIONS: The conjugation of the selected contact lens solutions with AgTANPs might be a novel and promising approach for the prevention of AK infections among contact lens users.


Asunto(s)
Queratitis por Acanthamoeba/prevención & control , Acanthamoeba castellanii/efectos de los fármacos , Soluciones para Lentes de Contacto/farmacología , Nanopartículas del Metal/química , Plata/farmacología , Taninos/farmacología , Animales , Humanos
14.
Int J Nanomedicine ; 15: 4969-4990, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32764930

RESUMEN

BACKGROUND: Polyphenols possess antioxidant, anti-inflammatory and antimicrobial properties and have been used in the treatment of skin wounds and burns. We previously showed that tannic acid-modified AgNPs sized >26 nm promote wound healing, while tannic acid-modified AgNPs sized 13 nm can elicit strong local inflammatory response. In this study, we tested bimetallic Au@AgNPs sized 30 nm modified with selected flavonoid and non-flavonoid compounds for wound healing applications. METHODS: Bimetallic Au@AgNPs were obtained by growing an Ag layer on AuNPs and further modified with selected polyphenols. After toxicity tests and in vitro scratch assay in HaCaT cells, modified lymph node assay as well as the mouse splint wound model were further used to access the wound healing potential of selected non-toxic modifications. RESULTS: Tannic acid, gallic acid, polydatin, resveratrol, catechin, epicatechin, epigallocatechin, epicatechin gallate, epigallocatechin gallate and procyanidin B2 used to modify Au@AgNPs exhibited good toxicological profiles in HaCaT cells. Au@AgNPs modified with 15 µM tannic acid, 200 µM resveratrol, 200 µM epicatechin gallate, 1000 µM gallic acid and 200 µM procyanidin B2 induced wound healing in vivo and did not lead to the local irritation or inflammation. Tannic acid-modified Au@AgNPs induced epithelial-to-mesenchymal transition (EMT) - like re-epithelialization, while other polyphenol modifications of Au@AgNPs acted through proliferation and wound closure. CONCLUSION: Bimetallic Au@AgNPs can be used as a basis for modification with selected polyphenols for topical uses. In addition, we have demonstrated that particular polyphenols used to modify bimetallic nanoparticles may show different effects upon different stages of wound healing.


Asunto(s)
Oro/química , Nanopartículas del Metal/química , Polifenoles/química , Polifenoles/farmacología , Plata/química , Cicatrización de Heridas/efectos de los fármacos , Animales , Antioxidantes/química , Antioxidantes/farmacología , Biflavonoides/química , Catequina/análogos & derivados , Catequina/química , Ratones , Proantocianidinas/química , Taninos/química
15.
Toxicol In Vitro ; 65: 104774, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-31954849

RESUMEN

The aim of this study was to assess whether silver nanoparticles (AgNP) or selected cosmetic ingredients may modify functions of various immunocompetent cell populations. To this end, the effect of two AgNP (size of 15 nm or 45 nm), alone and in combination with aluminium chloride, butyl paraben, di-n-butyl phthalate or diethyl phthalate was assessed on: (1) migration and invasion of MDA-MB-231 human breast cancer cells; (2) M1/M2 polarization of phorbol 12-myristate 13-acetate (PMA)-differentiated THP-1 macrophages (M0) and (3) activation/maturation of monocyte-derived dendritic cells (DCs). The results of this study showed that neither any of the test chemicals alone nor the mixtures significantly changed the migration or invasion ability of MDA-MB-231 cells following, both 72-h and 21-day exposure. Analysis of the expression of marker genes for both M1 (IL-1B, CXCL9, TNF) and M2 (DCSIGN, MRC1) polarization revealed that the chemicals/mixtures did not activate M1/M2 differentiation of the M0 macrophages. In addition, no significant changes were observed in the expression of CD86, HLA-DR and CD54 surface markers and phagocytic activity of DCs following 48-h exposure to AgNP alone or in combination with test compounds. Our study suggests that AgNP alone or in combination with tested cosmetic ingredients do not alter function of immunocompetent cells studied.


Asunto(s)
Cloruro de Aluminio/administración & dosificación , Neoplasias de la Mama/inmunología , Cosméticos/administración & dosificación , Nanopartículas del Metal/administración & dosificación , Parabenos/administración & dosificación , Ácidos Ftálicos/administración & dosificación , Plata/administración & dosificación , Neoplasias de la Mama/genética , Línea Celular Tumoral , Movimiento Celular/efectos de los fármacos , Células Dendríticas/efectos de los fármacos , Células Dendríticas/fisiología , Interacciones Farmacológicas , Expresión Génica , Humanos , Macrófagos/efectos de los fármacos , Macrófagos/inmunología , Monocitos/citología , Fagocitosis/efectos de los fármacos
16.
RSC Adv ; 10(63): 38424-38436, 2020 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-35517546

RESUMEN

This study describes a new method for passivating Ag nanoparticles (AgNPs) with SnO2 layer and their further treatment by microwave irradiation. The one-step process of SnO2 layer formation was carried out by adding sodium stannate to the boiling aqueous AgNPs solution, which resulted in the formation of core@shell Ag@SnO2 nanoparticles. The coating formation was a tunable process, making it possible to obtain an SnO2 layer thickness in the range from 2 to 13 nm. The morphology, size, zeta-potential, and optical properties of the Ag@SnO2NPs were studied. The microwave irradiation significantly improved the environmental resistance of Ag@SnO2NPs, which remained stable in different biological solutions such as NaCl at 150 mM and 0.1 M, Tris-buffered saline buffer at 0.1 M, and phosphate buffer at pH 5.6, 7.0, and 8.0. Ag@SnO2NPs after microwave irradiation were also stable at biologically relevant pH values, both highly acidic (1.4) and alkaline (13.2). Moreover, AgNPs covered with a 13 nm-thick SnO2 layer were resistant to cyanide up to 0.1 wt%. The microwave-treated SnO2 shell can facilitate the introduction of AgNPs in various solutions and extend their potential application in biological environments by protecting the metal nanostructures from dissolution and aggregation.

17.
Nanomedicine (Lond) ; 15(1): 23-39, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31868116

RESUMEN

Aim: Superoxide dismutase (SOD) and catalase (CAT) immobilized on gold nanoparticles (AuNP) and silver nanoparticles (AgNP) nanoparticles were used to reduce UV radiation-induced oxidative stress in rat skin. Materials & methods: The antioxidant influence of the enzymes was investigated on level of malondialdehyde, 8-hydroksy-2'deoksyguanozine, myeloperoxidase, total antioxidant capacity, SOD2 and CAT activity and expression, and glutathione and glutathione peroxidase activity. Results: The application of immobilized SOD and CAT on UV-irradiated skin reduced malondialdehyde and 8-hydroksy-2'deoksyguanozine levels also SOD and CAT activity and expression increased. The tested enzymes influence glutathione peroxidase activity and level of total antioxidant capacity and glutathione. Conclusion: Immobilized enzymes increased the antioxidative potential of skin following UV irradiation.


Asunto(s)
Antioxidantes/farmacología , Enzimas Inmovilizadas/farmacología , Estrés Oxidativo/efectos de los fármacos , Protectores contra Radiación/farmacología , Piel/efectos de los fármacos , Animales , Antioxidantes/química , Catalasa/química , Catalasa/farmacología , Enzimas Inmovilizadas/química , Glutatión/química , Oro/química , Humanos , Malondialdehído/química , Nanopartículas del Metal/química , Protectores contra Radiación/química , Ratas , Especies Reactivas de Oxígeno/metabolismo , Piel/patología , Piel/efectos de la radiación , Superóxido Dismutasa/química , Superóxido Dismutasa/farmacología , Rayos Ultravioleta/efectos adversos
18.
Colloids Surf B Biointerfaces ; 177: 19-24, 2019 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-30690426

RESUMEN

Plant extracts are known for their antihyperglycemic, antioxidant, antimutagenic, antifungal, anti-inflammatory, antiviral and antibacterial properties. These biological properties make plant extracts interesting surface modifiers of nanoparticles (NPs), which are also known for their unique features. Plant extracts can play a multifunctional role in the synthesis of NPs (i.e. can act as a reducing agent, stabiliser and bioactive compound), which gives additional properties to the final hybrid material. The combination of an extract of natural origin with NPs results in bioconjugates with unique final properties that often may not be obvious. The properties of a bioconjugate depend on both the plant extract (chemical composition, amount, a method of conjugation to NP surface, etc.) and the NPs (type, size, shape, polydispersity, etc.). Syntheses of NPs with plant extract usually lead to polydisperse particles with heterogeneous properties that are difficult to control from a biological point of view. In this paper, we present a synthesis protocol to obtain monodisperse silver nanoparticles (AgNPs) with plant extract. Cacao beans and grape seed extracts were selected as natural sources of polyphenols having biomedical importance (e.g. catechin, tannic acid, epicatechin gallate) and used to synthesise using a chemical reduction method. Syntheses were carried out with different molar ratios of reagents to find the best conditions for obtaining AgNPs that are homogeneous in size and shape. The colloids obtained were characterised with ultraviolet-visible (UV-Vis) spectroscopy, scanning transmission electron microscopy (STEM) and dynamic light scattering (DLS). It was found that syntheses carried out only with plant extract resulted in unstable colloids containing polydisperse nanoparticles. Stable colloids containing spherical monomodal particles were obtained by the incorporation of sodium citrate as an additional reagent in the synthesis mixture. The results obtained clearly indicate the crucial role of sodium citrate in the synthesis of spherical AgNPs of controlled size using plant extracts for biological applications.


Asunto(s)
Nanopartículas del Metal/química , Extractos Vegetales/química , Plata/química , Cacao/química , Semillas/química , Vitis/química
19.
Appl Biochem Biotechnol ; 187(4): 1551-1568, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-30284207

RESUMEN

Superoxide dismutase (SOD) is one of the best characterized enzyme maintaining the redox state in the cell. A bacterial expression system was used to produce human recombinant manganese SOD with a His-tag on the C-end of the protein for better purification. In addition, gold and silver nanoparticles were chemically synthesized in a variety of sizes, and then mixed with the enzyme for immobilization. Analysis by dynamic light scattering and scanning transmission electron microscopy revealed no aggregates or agglomerates of the obtained colloids. After immobilization of the protein on AuNPs and AgNPs, the conjugates were analyzed by SDS-PAGE. It was determined that SOD was adsorbed only on the gold nanoparticles. Enzyme activity was analyzed in colloids of the gold and silver nanoparticles bearing SOD. The presence of a nanoparticle did not affect enzyme activity; however, the amount of protein and size of the gold nanoparticle did influence the enzymatic activity of the conjugate. Our findings confirm that active recombinant human superoxide dismutase can be produced using a bacterial expression system, and that the enzyme can be immobilized on metal nanoparticles. The interaction between enzymes and metal nanoparticles requires further investigation.


Asunto(s)
Oro/química , Oro/farmacología , Nanopartículas del Metal/química , Proteínas Recombinantes/metabolismo , Plata/química , Plata/farmacología , Superóxido Dismutasa/metabolismo , Humanos , Estrés Oxidativo/efectos de los fármacos , Tamaño de la Partícula , Transporte de Proteínas/efectos de los fármacos
20.
Viruses ; 10(10)2018 09 26.
Artículo en Inglés | MEDLINE | ID: mdl-30261662

RESUMEN

(1) Background: Tannic acid is a plant-derived polyphenol showing antiviral activity mainly because of an interference with the viral adsorption. In this work, we tested whether the modification of silver nanoparticles with tannic acid (TA-AgNPs) can provide a microbicide with additional adjuvant properties to treat genital herpes infection. (2) Methods: The mouse model of the vaginal herpes simplex virus 2 (HSV-2) infection was used to test immune responses after treatment of the primary infection with TA-AgNPs, and later, after a re-challenge with the virus. (3) Results: The mice treated intravaginally with TA-AgNPs showed better clinical scores and lower virus titers in the vaginal tissues soon after treatment. Following a re-challenge, the vaginal tissues treated with TA-AgNPs showed a significant increase in the percentages of IFN-gamma+ CD8+ T-cells, activated B cells, and plasma cells, while the spleens contained significantly higher percentages of IFN-gamma+ NK cells and effector-memory CD8+ T cells in comparison to NaCl-treated group. TA-AgNPs-treated animals also showed significantly better titers of anti-HSV-2 neutralization antibodies in sera; and (4) Conclusions: Our findings suggest that TA-AgNPs sized 33 nm can be an effective anti-viral microbicide to be applied upon the mucosal tissues with additional adjuvant properties enhancing an anti-HSV-2 immune response following secondary challenge.


Asunto(s)
Antivirales/farmacología , Genitales Femeninos/virología , Herpes Genital/tratamiento farmacológico , Herpesvirus Humano 2/inmunología , Plata/farmacología , Taninos/farmacología , Taninos/uso terapéutico , Animales , Anticuerpos Neutralizantes/inmunología , Antivirales/química , Antivirales/uso terapéutico , Femenino , Herpes Genital/inmunología , Herpes Genital/virología , Herpesvirus Humano 2/química , Inmunidad Mucosa/inmunología , Nanopartículas del Metal/química , Nanopartículas del Metal/uso terapéutico , Ratones , Ratones Endogámicos C57BL , Plata/química , Taninos/química
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