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1.
Antioxidants (Basel) ; 12(4)2023 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-37107352

RESUMO

Obesity is a global health issue, in which modifications in gut microbiota composition have a key role. Different therapeutic strategies are being developed in combination with diet and exercise, including the use of plant extracts, such as those obtained from Morus alba L. leaves. Recent studies have revealed their anti-inflammatory and antioxidant properties. The aim of the present work was to evaluate whether the beneficial effects of M. alba L. leaf extract in high-fat diet-induced obesity in mice is correlated with its impact on gut microbiota. The extract reduced body weight gain and attenuated lipid accumulation, as well as increased glucose sensitivity. These effects were associated with an amelioration of the obesity-associated inflammatory status, most probably due to the described antioxidant properties of the extract. Moreover, M. alba L. leaf extract mitigated gut dysbiosis, which was evidenced by the restoration of the Firmicutes/Bacteroidota ratio and the decrease in plasma lipopolysaccharide (LPS) levels. Specifically, the extract administration reduced Alistipes and increased Faecalibaculum abundance, these effects being correlated with the beneficial effects exerted by the extract on the obesity-associated inflammation. In conclusion, anti-obesogenic effects of M. alba L. leaf extract may be mediated through the amelioration of gut dysbiosis.

2.
Molecules ; 27(24)2022 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-36557924

RESUMO

During the last decade there has been growing interest in the formulation of new cosmetic, food and pharmaceutical products containing natural compounds with antioxidant activity and other beneficial properties. Aromatic and medicinal plants have always been the major source of bioactive compounds, especially, wild thyme (Thymbra capitata L.), which has been used since ancient times for its valuable health benefits that could be attributed to the richness of polyphenolic compounds. This study was undertaken with the following aims: to estimate the total polyphenolic content (TPC); to evaluate the antioxidant activity; to identify and quantify the phenolic compounds of post-distilled residues of Tunisian thyme, and their contribution to the antioxidant activity. The TPC, as determined by the Folin−Ciocalteu method, was found to reach the values of 126.7 and 107.84 mg gallic acid equivalent/g plant dry weight (mg GAE/g PDW). The antioxidant activity, which is assessed by DPPH and FRAP assays, reached the values of 42.97−45.64 µg/mL and 42.22−50.21 mMFe2+/mg PDW, respectively. HPLC analysis revealed the presence of fourteen polyphenolic compounds, of which diosmin and rosmarinic acid were found to be the most abundant (24.26 to 33.80 and 22.0.1 to 26.29 mg/g PDW, respectively). An important correlation was found between the antioxidant activity and several identified phenolic compounds (p < 0.05). The findings revealed that thyme post-distilled residues have an effective natural antioxidant potential due to their high concentration of bioactive molecules, and they appear to be useful in the pharmaceutical, cosmetic, and food industries, with beneficial effects on human health. Therefore, supplementing a balanced diet with herbs may have beneficial health effects.


Assuntos
Lamiaceae , Plantas Medicinais , Thymus (Planta) , Humanos , Antioxidantes/química , Fenóis/química , Extratos Vegetais/química , Ácido Gálico/análise , Plantas Medicinais/química , Lamiaceae/química
3.
Soft Matter ; 18(26): 4973-4982, 2022 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-35748816

RESUMO

Silk gut fibers were produced from the silkworm Samia cynthia ricini silk glands by the usual procedure of immersion in a mildly acidic solution and subsequent stretching. The morphology of the silk guts was assessed by scanning electron microscopy, and their microstructure was assessed by infrared spectroscopy and X-ray diffraction. It was found that both naturally spun and Samia silk guts share a common semicrystalline microstructure. The mechanical characterization of the silk guts revealed that these fibers show an elastomeric behavior when tested in water, and exhibit a genuine ground state to which the fiber may revert independently of its previous loading history. In spite of its large cross-sectional area compared with naturally spun silk fibers, Samia silk guts show values of work to fracture up to 160 MJ m-3, much larger than those of most of their natural counterparts, and establish a new record value for this parameter in silk guts.


Assuntos
Bombyx , Seda , Animais , Seda/química , Espectrofotometria Infravermelho , Difração de Raios X
4.
Polymers (Basel) ; 14(3)2022 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-35160487

RESUMO

In recent years, silk fibroin nanoparticles (SFNs) have been consolidated as drug delivery systems (DDSs) with multiple applications in personalized medicine. The design of a simple, inexpensive, and scalable preparation method is an objective pursued by many research groups. When the objective is to produce nanoparticles suitable for biomedical uses, their sterility is essential. To achieve sufficient control of all the crucial stages in the process and knowledge of their implications for the final characteristics of the nanoparticles, the present work focused on the final stage of sterilization. In this work, the sterilization of SFNs was studied by comparing the effect of different available treatments on the characteristics of the nanoparticles. Two different sterilization methods, gamma irradiation and autoclaving, were tested, and optimal conditions were identified to achieve the sterilization of SFNs by gamma irradiation. The minimum irradiation dose to achieve sterilization of the nanoparticle suspension without changes in the nanoparticle size, polydispersity, or Z-potential was determined to be 5 kiloGrays (kGy). These simple and safe methods were successfully implemented for the sterilization of SFNs in aqueous suspension and facilitate the application of these nanoparticles in medicine.

5.
Int J Pharm ; 606: 120935, 2021 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-34310954

RESUMO

Inflammatory bowel disease (IBD) is a chronic and idiopathic inflammatory disorder affecting the gastrointestinal tract. The pharmacological treatments used currently for its treatment lack efficacy, so new therapeutic strategies should be developed. In this context, flavonoids loaded in biopolymeric nanoparticles can be considered as novel promising candidates. The aim of the present study was to evaluate the intestinal anti-inflammatory effects of quercetin when is administered loaded in silk fibroin nanoparticles (QSFN) in the dextran sulphate sodium experimental model of mouse colitis, which displays some similarities to human IBD. Previously characterized quercetin-loaded silk fibroin nanoparticles (QSFN). QSFN showed a reversible aggregation profile induced by the acidification of the solution but did not affect the loaded quercetin. Daily administration of QSFN significantly reduced disease activity index values compared to the control colitic group. This beneficial effect was not only corroborated by the histological examination of the colonic specimens but also the improvement of the colonic expression of the different proinflammatory cytokines (Tnf-α, Il-1ß, Il-6, Mcp-1, Icam-1, Nlrp3 and iNOS). Therefore, these data suggest that QSFN could be a promising alternative to current treatments as a drug delivery system for IBD treatment.


Assuntos
Colite , Fibroínas , Nanopartículas , Animais , Colite/induzido quimicamente , Colite/tratamento farmacológico , Colo , Citocinas , Sulfato de Dextrana , Modelos Animais de Doenças , Camundongos , Camundongos Endogâmicos C57BL , Quercetina
6.
Lab Chip ; 21(3): 608-615, 2021 02 07.
Artigo em Inglês | MEDLINE | ID: mdl-33404577

RESUMO

In optical biosensing, silk fibroin (SF) appears as a promising alternative where other materials, such as paper, find limitations. Besides its excellent optical properties and unmet capacity to stabilize biomacromolecules, SF in test strips exhibits additional functions, i.e. capillary pumping activity of 1.5 mm s-1, capacity to filter blood cells thanks to its small, but tuneable, porosity and enhanced biosensing sensitivity. The bulk functionalization of SF with the enzymes glucose oxidase and peroxidase and the mediator ABTS produces colourless and transparent SF films that respond to blood glucose increasing 2.5 times the sensitivity of conventional ABTS-based assays. This enhanced sensitivity results from the formation of SF-ABTS complexes, where SF becomes part of the bioassay. Additionally, SF films triple the durability of most stable cellulose-based sensors. Although demonstrated for glucose, SF microfluidic test strips may incorporate other optical bioassays, e.g. immunoassays, with the aim of transferring them from central laboratories to the place of patient's care.


Assuntos
Glicemia/análise , Fibroínas , Nanoporos , Ação Capilar , Humanos
7.
Sci Rep ; 10(1): 18471, 2020 10 28.
Artigo em Inglês | MEDLINE | ID: mdl-33116211

RESUMO

Spider mites constitute an assemblage of well-known pests in agriculture, but are less known for their ability to spin silk of nanoscale diameters and high Young's moduli. Here, we characterize silk of the gorse spider mite Tetranychus lintearius, which produces copious amounts of silk with nano-dimensions. We determined biophysical characteristics of the silk fibres and manufactured nanoparticles and biofilm derived from native silk. We determined silk structure using attenuated total reflectance Fourier transform infrared spectroscopy, and characterized silk nanoparticles using field emission scanning electron microscopy. Comparative studies using T. lintearius and silkworm silk nanoparticles and biofilm demonstrated that spider mite silk supports mammalian cell growth in vitro and that fluorescently labelled nanoparticles can enter cell cytoplasm. The potential for cytocompatibility demonstrated by this study, together with the prospect of recombinant silk production, opens a new avenue for biomedical application of this little-known silk.


Assuntos
Materiais Biocompatíveis , Teste de Materiais , Nanopartículas/química , Seda/química , Tetranychidae/química , Animais , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacocinética , Materiais Biocompatíveis/farmacologia , Linhagem Celular , Módulo de Elasticidade , Camundongos , Microscopia Eletrônica de Varredura , Nanopartículas/ultraestrutura
8.
Antioxidants (Basel) ; 9(8)2020 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-32796677

RESUMO

Increased levels of reactive oxygen species (ROS) and a low-grade chronic inflammation in multiple organs have been demonstrated in obesity. Morus alba leaves extracts (MAEs) have been used in traditional medicine as anti-inflammatory agents. In this work, the bioactive compounds of different genotypes of M. alba L. (Filipina, Valenciana Temprana, Kokuso, and Italia) were analyzed not only by reverse phase high performance liquid chromatography-electrospray ionization-time of flight-mass spectrometry (RP-HPLC-ESI-TOF-MS) and hydrophilic interaction chromatography-electrospray ionization-time of flight-mass spectrometry (HILIC-ESI-TOF-MS), but also screened for in vitro and in vivo antioxidant activity by means of DPPH· radical scavenging assay and Caenorhabditis elegans model. These MAEs were administered daily in a model of diet-induced obesity in mice. Filipina and Italia genotypes significantly reduced weight gain, the glycemic levels in high fat diet, as well as, levels of LDL-cholesterol and triglycerides. Filipina and Italia MAEs also reduced the expression of proinflammatory mediators such as Tnf-α, Il-1ß, Il-6 and increased the levels of adiponectin and AMPK, which exert anti-inflammatory effects. Moreover, Italia genotype ameliorated the intestinal barrier function. In conclusion, Filipina and Italia methanolic extracts show the highest antioxidant and anti-inflammatory effect, due to the presence of compounds such as protocatechuic acid or quercetin-3-glucoside, and they could be developed as a complementary treatment for obesity and metabolic disorders.

9.
Carbohydr Polym ; 237: 116107, 2020 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-32241442

RESUMO

This work aims to design biocompatible aerogel sponges that can host and control the release of stromal cell-derived factor-1α (SDF-1α or CXCL12), a key protein for applications ranging from regenerative medicine to cancer therapy (notably for neural tissues). Miscibility of silk fibroin (SF) and hyaluronic acid (HA) was investigated by means of fluorescence and scanning electron microscopy to identify processing conditions. Series of freeze-dried sponges were prepared by associating and cross-linking within the same 3D structure, HA, SF, poly-l-lysine (PLL) and heparin (hep). Aerogel sponges presented high swelling degree and porosity (∼90 %), adequate mean pore diameter (ca. 60 µm) and connectivity for welcoming cells, and a soft texture close to that of the brain (6-13 kPa Young's Modulus). Addition of SF yielded sponges with slower biodegradation. SF-HA and SF-HA-hep sponges retained 75 % and 93 % of the SDF-1α respectively after 7 days and were found to be cytocompatible in vitro.


Assuntos
Materiais Biocompatíveis/química , Géis , Engenharia Tecidual , Alicerces Teciduais/química , Animais , Materiais Biocompatíveis/síntese química , Quimiocina CXCL12/química , Fibroínas/química , Géis/síntese química , Géis/química , Heparina/química , Ácido Hialurônico/química , Camundongos , Células NIH 3T3 , Porosidade
10.
Antioxidants (Basel) ; 9(1)2020 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-31963913

RESUMO

OBJECTIVE: the objective of the present work is to study the effectiveness of treatment with silk fibroin nanoparticles loaded with resveratrol in experimental periodontitis in a diabetic rat model. INTRODUCTION: Periodontitis is an inflammatory pathology highly related to other diseases, such as type II diabetes. Both diseases have a specific inflammatory condition, with Interleukin (IL)-6, IL-1ß and Transforming Grow Factor (TGF)-1ß being the most relevant proinflammatory factors. Silk fibroin (SF) nanoparticles loaded with resveratrol (Res-SFN) are a new alternative as a treatment. METHODS: 40 diabetic Sprague Dawley male rats were used and periodontitis was induced by ligation. The animals were divided into 5 treatment groups, and 1 mL of treatment was administered once a day for 4 weeks. The groups were: I: Carboxymethyl cellulose (CMC) 0.8%, II: CMC 0.8% + SF 1%, III: CMC 0.8% + RES-SFN 3 mg/mL, IV: CMC 0.8% + SF 1% + RES-SFN 3 mg/mL, V: Water. A peripheral blood sample was taken every week to quantify the inflammatory profile by ELISA (IL-6, IL-1ß and TGF-1ß). After 4 weeks the sacrifice was carried out and biopsies of the gum were taken. RESULTS: Treatment with SF and RES-SFN reduced the amount of chemical inflammation mediators (with the exception of IL-1ß in comparisons I-IV and II-IV (p > 0.05)), as well as the anatomopathological variables linked to it, in a significant way (p < 0.05). CONCLUSION: treatment with RES-SFN has reduced local inflammation in this experimental periodontitis model.

11.
ACS Biomater Sci Eng ; 6(6): 3299-3309, 2020 06 08.
Artigo em Inglês | MEDLINE | ID: mdl-33463164

RESUMO

This work aims to provide an effective and novel dual tool for the biodistribution studies of biopolimeric nanoparticles by using modified silk fibroin nanoparticles as a model. This is an indispensable step in the evaluation of the applicability of biopolymeric nanoparticles as drug delivery systems. In this work, we report a new facile method for radiolabeling silk fibroin nanoparticles conjugated to the chelating agent diethylenetriamine pentaacetic acid and tagged with fluorescein isothiocyanate. Nanoparticles were characterized by means of dynamic light scattering, scanning electron microscopy, and infrared and fluorescence spectroscopy. The in vitro studies included stability in biological media and evaluation of the cytotoxicity of the nanoparticles in a cell culture. The in vivo study was focused on a scintigraphic study over 24 h conducted on New Zealand rabbits, after intra-articular injection of [111In]In-nanoparticles containing 8.03 ± 0.42 MBq. Biodistribution of the nanoparticles was also assessed ex vivo by fluorescence microscopy of post mortem biopsied organs. This radiolabeling method was reproducible and robust with high radiolabeling efficiency (∼80%) and high specific activity suitable for in vivo studies. Radiolabeled nanoparticles, having a hydrodynamic radius of 113.2 ± 2.3 nm, a polydispersity index of 0.101 ± 0.015, and a Z-potential of -30.1 ± 2.0 mV, showed an optimum retention in the articular space, without activity clearance up to 24 h post injection. Thus, an easy and robust radiolabeling method has been developed, and its applicability is demonstrated in vitro and in vivo studies, showing its value for future investigation of silk fibroin nanoparticles as versatile and stable (steady) local drug delivery systems for consideration as a therapeutic option, particularly in the treatment of joint disorders.


Assuntos
Fibroínas , Nanopartículas , Animais , Sistemas de Liberação de Medicamentos , Ácido Pentético , Coelhos , Distribuição Tecidual
12.
Polymers (Basel) ; 11(12)2019 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-31835438

RESUMO

Several studies have stated that the process used for sericin removal, or degumming, from silk cocoons has a strong impact in the silk fibroin integrity and consequently in their mechanical or biochemical properties after processing it into several biomaterials (e.g. fibers, films or scaffolds) but still, there is a lack of information of the impact on the features of silk nanoparticles. In this work, silk cocoons were degummed following four standard methods: autoclaving, short alkaline (Na2CO3) boiling, long alkaline (Na2CO3) boiling and ultrasounds. The resultant silk fibroin fibers were dissolved in the ionic liquid 1-ethyl-3-methylimidazolium acetate and used for nanoparticle synthesis by rapid desolvation in polar organic solvents. The relative efficiencies of the degumming processes and the integrity of the resulting fibroin fibers obtained were analyzed by mass loss, optical microscopy, thermogravimetric analysis, infrared spectroscopy and SDS-PAGE. Particle sizes and morphology were analyzed by Dynamic Light Scattering and Field Emission Scanning Electronic Microscopy. The results showed that the different treatments had a remarkable impact on the integrity of the silk fibroin chains, as confirmed by gel electrophoresis, which can be correlated with particle mean size and size distribution changes. The smallest nanoparticles (156 ± 3 nm) and the most negative Z potential (-30.2 ± 1.8 mV) were obtained with the combination of long treatment (2 h) of boiling in alkaline solution (Na2CO3 0.02 eq/L). The study confirms that parameters of the process, such as composition of the solution and time of the degumming step, must be controlled in order to reach an optimum reproducibility of the nanoparticle production.

13.
Soft Matter ; 15(14): 2960-2970, 2019 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-30901019

RESUMO

Tubuliform silk glands were dissected from Nephila clavipes spiders, and silk gut fibers were produced by immersing the glands in a mild acid solution and subsequent stretching. The tensile properties of the as produced fibers were obtained through tensile tests, and the stress-strain curves were compared with those of naturally spun tubuliform silk fibers. The influence on the mechanical properties of the fibers after immersion in water and drying was also discerned. The microstructure of the silk guts was obtained by X-ray diffraction (XRD) and infrared spectroscopy (FTIR). It was found that the stress-strain curves of the stretched tubuliform silk guts concur with those of their natural counterparts (tubuliform silk fibers).


Assuntos
Seda/química , Aranhas/química , Animais , Resistência à Tração
14.
Int J Pharm ; 527(1-2): 115-125, 2017 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-28539234

RESUMO

Regenerative medicine seeks advanced solutions for bone repair in the form of bioactive synthetic scaffolds by using simple and reproducible processing techniques. In this work, poly-ε-caprolactone (PCL)-based porous scaffolds with improved osteoconductive and osteoinductive properties were processed by supercritical foaming through a careful tuning of components and processing conditions. Composite scaffolds were prepared from various combinations of PCL, silk fibroin and nano-hydroxyapatite (nHA). The green and cost-effective supercritical CO2 foaming method applied rendered solid scaffolds with 67-70% porosity. The incorporation of fibroin and nHA in the scaffolds increased the compressive modulus, cellular adhesion and calcium deposition. The composite scaffolds were tested in vivo in a large-scale calvarial defect model, and bone regeneration was evaluated for up to 14 weeks after implantation. Histomorphometric results showed that all implanted constructs gave rise to the endochondral bone formation and unveiled the synergistic effect of silk fibroin and nHA on the bone repair extent. The information gathered may shed light on the design and processing criteria of bioactive bone scaffolds.


Assuntos
Regeneração Óssea , Durapatita/química , Fibroínas/química , Engenharia Tecidual , Alicerces Teciduais , Células 3T3 , Animais , Química Verde , Masculino , Camundongos , Poliésteres , Porosidade , Ratos Sprague-Dawley
15.
J Craniofac Surg ; 28(4): 939-943, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28230598

RESUMO

Among various biomaterials used as scaffolds in tissue engineering, silk fibroin is a highly attractive material. A scaffold should be biocompatible and nontoxic, with optimal physical features and mechanical properties. For this reason, tissue-engineering approaches in regenerative medicine have focused on investigating the biocompatibility of possible biomaterials by analyzing cell-scaffold interaction properties. The aim of the present study was to examine the biocompatibility of silk fibroin as a film (two-dimensional [2D]) and a scaffold (three-dimensional [3D]) after being cellularized with human dental pulp stem cells (hDPSCs). Human dental pulp stem cells were isolated from healthy patients aged between 18 and 31 years. Further, silk fibroin-based 2D films and 3D scaffolds were prepared. Human dental pulp stem cells were directly seeded onto the biomaterial surfaces and their proliferation, adherence, and cell morphology were analyzed after 24, 120, and 168 hours. Additionally, the characteristics of the silk fibroin 2D films and 3D scaffolds before and after cell seeding were analyzed by scanning electron microscopy. After the initial 24 hours, silk fibroin-based 3D scaffolds displayed more adhered cells with a suitable fibroblastic morphology than those displayed on the 2D films. After longer culture times, hDPSCs proliferated sufficiently to cover the entire surface of the 3D silk fibroin scaffold, whereas the 2D films were only partially covered. Our results indicate the good in vitro biocompatibility of silk fibroin-based biomaterials, especially when 3D scaffolds rather than 2D films are used.


Assuntos
Células-Tronco Adultas/fisiologia , Materiais Biocompatíveis , Adesão Celular , Polpa Dentária/citologia , Fibroínas , Engenharia Tecidual/métodos , Alicerces Teciduais , Adolescente , Adulto , Células-Tronco Adultas/citologia , Animais , Proliferação de Células , Humanos , Adulto Jovem
16.
Int J Pharm ; 518(1-2): 11-19, 2017 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-28012995

RESUMO

This article describes how silk fibroin nanoparticles (SFNs) are capable of adsorbing and releasing quercetin (Q) and how its integrity is highly preserved, as confirmed by antioxidant activity assays. Q loading onto SFNs was optimized in terms of the Q/SFN ratio (w/w), time of adsorption and solvent mixture. Quercetin-loaded silk fibroin nanoparticles (QSFNs) were characterized using the dynamic light scattering technique to measure the diameter (Z-Average) and Z-potential (ζ). Loaded particles were slightly bigger than the SFNs, while their ζ was less negative. The antioxidant activity against DPPH showed that the Q loaded in QSFNs not only retains the antioxidant activity but also has a synergistic scavenging activity due the intrinsic antioxidant activity of the SF. The drug loading content (DLC) and the encapsulation efficiency (EE) varied with the relation between Q and SFN in the loading solution. The sustained release of Q occurred throughout the experiment both in phosphate buffer saline (pH 7.4) and simulated intestinal fluid (pH 6.8). The results point to SFNs as promising candidates for Q loading, transport and gastrointestinal delivery with potential applications in nanomedicine, while retaining their nano-size and their antioxidant properties.


Assuntos
Antioxidantes/química , Sistemas de Liberação de Medicamentos , Fibroínas/química , Nanopartículas/química , Quercetina/química , Adsorção , Compostos de Bifenilo/química , Liberação Controlada de Fármacos , Fibroínas/ultraestrutura , Microscopia Eletrônica de Varredura , Nanopartículas/ultraestrutura , Picratos/química
17.
Int J Nanomedicine ; 11: 5945-5958, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27877040

RESUMO

BACKGROUND: Current treatment of inflammatory bowel disease is based on the use of immunosuppressants or anti-inflammatory drugs, which are characterized by important side effects that can limit their use. Previous research has been performed by administering these drugs as nanoparticles that target the ulcerated intestinal regions and increase their bioavailability. It has been reported that silk fibroin can act as a drug carrier and shows anti-inflammatory properties. PURPOSE: This study was designed to enhance the interaction of the silk fibroin nanoparticles (SFNs) with the injured intestinal tissue by functionalizing them with the peptide motif RGD (arginine-glycine-aspartic acid) and to evaluate the intestinal anti-inflammatory properties of these RGD-functionalized silk fibroin nanoparticles (RGD-SFNs) in the trinitrobenzenesulfonic acid (TNBS) model of rat colitis. MATERIALS AND METHODS: SFNs were prepared by nanoprecipitation in methanol, and the linear RGD peptide was linked to SFNs using glutaraldehyde as the crosslinker. The SFNs (1 mg/rat) and RGD-SFNs (1 mg/rat) were administered intrarectally to TNBS-induced colitic rats for 7 days. RESULTS: The SFN treatments ameliorated the colonic damage, reduced neutrophil infiltration, and improved the compromised oxidative status of the colon. However, only the rats treated with RGD-SFNs showed a significant reduction in the expression of different pro-inflammatory cytokines (interleukin [IL]-1ß, IL-6, and IL-12) and inducible nitric oxide synthase in comparison with the TNBS control group. Moreover, the expression of both cytokine-induced neutrophil chemoattractant-1 and monocyte chemotactic protein-1 was significantly diminished by the RGD-SFN treatment. However, both treatments improved the intestinal wall integrity by increasing the gene expression of some of its markers (trefoil factor-3 and mucins). CONCLUSION: SFNs displayed intestinal anti-inflammatory properties in the TNBS model of colitis in rats, which were improved by functionalization with the RGD peptide.


Assuntos
Colite/tratamento farmacológico , Fibroínas/química , Fibroínas/farmacologia , Intestinos/efeitos dos fármacos , Nanopartículas/química , Oligopeptídeos/química , Ácido Trinitrobenzenossulfônico/farmacologia , Animais , Anti-Inflamatórios/química , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Colite/induzido quimicamente , Colite/imunologia , Colite/metabolismo , Citocinas/metabolismo , Modelos Animais de Doenças , Feminino , Fibroínas/uso terapêutico , Mucosa Intestinal/metabolismo , Intestinos/imunologia , Nanomedicina , Infiltração de Neutrófilos/efeitos dos fármacos , Óxido Nítrico Sintase Tipo II/metabolismo , Ratos , Ratos Wistar
18.
Stem Cells Dev ; 25(22): 1742-1754, 2016 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-27503546

RESUMO

Graphene represents one of the most interesting additions to the tissue engineering toolbox. Novel graphene-based composites are required to improve the beneficial graphene properties in terms of tridimensional polymeric structure, conferring a higher mechanical strength and favoring the differentiation of human mesenchymal stem cells. Here, we have demonstrated in a wide range of composite combinations, the successful use of graphene and silk-fibroin constructs for future bioengineering applications in the field of clinical regenerative dentistry using human periodontal ligament stem cells. Our results provide exciting new data for the development of suitable scaffolds that allow good cell engrafting, preservation of cell viability and proliferation, promotion of spontaneous osteoblastic differentiation, and importantly, stimulation of a higher cementum physiological synthesis than using other different available biomaterials.


Assuntos
Materiais Biocompatíveis/farmacologia , Diferenciação Celular/efeitos dos fármacos , Cemento Dentário/citologia , Fibroínas/farmacologia , Grafite/farmacologia , Osteoblastos/citologia , Ligamento Periodontal/citologia , Células-Tronco/citologia , Calcificação Fisiológica/efeitos dos fármacos , Calcificação Fisiológica/genética , Adesão Celular/efeitos dos fármacos , Adesão Celular/genética , Morte Celular/efeitos dos fármacos , Morte Celular/genética , Diferenciação Celular/genética , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/genética , Forma Celular/efeitos dos fármacos , Forma Celular/genética , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/genética , Células Cultivadas , Cemento Dentário/efeitos dos fármacos , Cemento Dentário/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Células-Tronco Mesenquimais/metabolismo , Osteoblastos/efeitos dos fármacos , Osteoblastos/metabolismo , Fenótipo , Células-Tronco/efeitos dos fármacos , Células-Tronco/ultraestrutura
19.
Int J Mol Sci ; 17(7)2016 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-27438824

RESUMO

This work describes a new approach to the delivery of light in deeper tissues, through a silk filament that is implantable, biocompatible, and biodegradable. In the present work, silkworm gut fibers (SGFs) of Bombyx mori L., are made by stretching the silk glands. Morphological, structural, and optical properties of the fibers have been characterized and the stimulatory effect of red laser light diffused from the fiber was assayed in fibroblast cultures. SGFs are formed by silk fibroin (SF) mainly in a ß-sheet conformation, a stable and non-soluble state in water or biological fluids. The fibers showed a high degree of transparency to visible and infrared radiation. Using a red laser (λ = 650 nm) as source, the light was efficiently diffused along the fiber wall, promoting a significant increment in the cell metabolism 5 h after the irradiation. SGFs have shown their excellent properties as light-diffusing optical fibers with a stimulatory effect on cells.


Assuntos
Materiais Biocompatíveis/química , Bombyx/metabolismo , Trato Gastrointestinal/metabolismo , Luz , Próteses e Implantes , Seda/química , Resistência à Tração/efeitos da radiação , Animais , Materiais Biocompatíveis/metabolismo , Proliferação de Células/efeitos da radiação , Células Cultivadas , Fibroblastos/citologia , Fibroblastos/metabolismo , Fibroblastos/efeitos da radiação , Camundongos , Seda/metabolismo
20.
Angew Chem Int Ed Engl ; 54(23): 6790-4, 2015 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-25951010

RESUMO

The current technology of air-filtration materials for protection against highly toxic chemicals, that is, chemical-warfare agents, is mainly based on the broad and effective adsorptive properties of hydrophobic activated carbons. However, adsorption does not prevent these materials from behaving as secondary emitters once they are contaminated. Thus, the development of efficient self-cleaning filters is of high interest. Herein, we report how we can take advantage of the improved phosphotriesterase catalytic activity of lithium alkoxide doped zirconium(IV) metal-organic framework (MOF) materials to develop advanced self-detoxifying adsorbents of chemical-warfare agents containing hydrolysable P-F, P-O, and C-Cl bonds. Moreover, we also show that it is possible to integrate these materials onto textiles, thereby combining air-permeation properties of the textiles with the self-detoxifying properties of the MOF material.


Assuntos
Substâncias para a Guerra Química/química , Substâncias para a Guerra Química/isolamento & purificação , Filtração/métodos , Compostos Organometálicos/química , Hidrolases de Triester Fosfórico/metabolismo , Têxteis , Zircônio/química , Adsorção , Biocatálise , Substâncias para a Guerra Química/toxicidade , Estrutura Molecular , Compostos Organometálicos/metabolismo , Zircônio/metabolismo
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