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1.
Int J Biol Macromol ; 267(Pt 2): 131410, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38582484

RESUMO

A complex illness with a current global hazard, colon cancer has many different manifestations. The efficacy of colon cancer therapy can be affected by the bacteria in the digestive tract. It is hypothesised that novel prebiotics like Gum Odina is emerging as preventative therapy to fight chronic gut illnesses by gut microbiota modulatory therapy when compared to traditional intervention. The first-line chemotherapy drug for colon cancer, capecitabine, lacks a carrier that can extend its half-life. Here, we use the prebiotic gum odina - sodium alginate conjugate to create a capecitabine loaded biopolymeric microspheres, which were previously established as excellent tools for colon cancer therapy. The accelerated stability study exhibited that the alteration in physicochemical properties was found to be negligible. When administered orally to mice with colon cancer, capecitabine raises intra-tumoral capecitabine concentration and slows drug elimination in the blood. Optimized formulation improves anti-tumor immunity over free capecitabine and decrease the tumor volume from 8 ±â€¯6.59 mm3 to 5.21 ±â€¯2.79 mm3. This prebiotics based microsphere combine's gut microbiota manipulation with chemotherapy to offer a potentially effective colon cancer treatment.


Assuntos
Capecitabina , Neoplasias do Colo , Microbioma Gastrointestinal , Microesferas , Prebióticos , Animais , Capecitabina/farmacologia , Camundongos , Neoplasias do Colo/tratamento farmacológico , Neoplasias do Colo/patologia , Microbioma Gastrointestinal/efeitos dos fármacos , Alginatos/química , Alginatos/farmacologia , Biopolímeros/química , Biopolímeros/farmacologia , Portadores de Fármacos/química
2.
Int J Biol Macromol ; 257(Pt 2): 128594, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38056744

RESUMO

Natural polymers and its mixtures in the form of films, sponges and hydrogels are playing a major role in tissue engineering and regenerative medicine. Hydrogels have been extensively investigated as standalone materials for drug delivery purposes as they enable effective encapsulation and sustained release of drugs. Biopolymers are widely utilised in the fabrication of hydrogels due to their safety, biocompatibility, low toxicity, and regulated breakdown by human enzymes. Among all the biopolymers, polysaccharide-based polymer is well suited to overcome the limitations of traditional wound dressing materials. Pectin is a polysaccharide which can be extracted from different plant sources and is used in various pharmaceutical and biomedical applications including cartilage regeneration. Pectin itself cannot be employed as scaffolds for tissue engineering since it decomposes quickly. This article discusses recent research and developments on pectin polysaccharide, including its types, origins, applications, and potential demands for use in AI-mediated scaffolds. It also covers the materials-design process, strategy for implementation to material selection and fabrication methods for evaluation. Finally, we discuss unmet requirements and current obstacles in the development of optimal materials for wound healing and bone-tissue regeneration, as well as emerging strategies in the field.


Assuntos
Neoplasias , Engenharia Tecidual , Humanos , Engenharia Tecidual/métodos , Pectinas/farmacologia , Neoplasias/tratamento farmacológico , Alicerces Teciduais , Cartilagem , Polissacarídeos/uso terapêutico , Polissacarídeos/farmacologia , Cicatrização , Biopolímeros/farmacologia , Polímeros/farmacologia , Hidrogéis/farmacologia , Materiais Biocompatíveis/farmacologia
3.
Chemosphere ; 328: 138587, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37019400

RESUMO

Synthesis and fabrication of naturally sourced biopolymers, especially chitosan, grafted with renewable small molecules have recently attracted attention as efficient antimicrobial agents and are highly desired for sustainable material development. Advantageous inherent functionalities in biobased benzoxazine extend the possibility of crosslinking with chitosan which holds immense potential. Herein, a low-temperature, greener facile methodology is adopted for the covalent confinement of benzoxazine monomers bearing aldehyde and disulfide linkages within chitosan to form benzoxazine-grafted-chitosan copolymer films. The association of benzoxazine as Schiff base, hydrogen bonding, and ring-opened structures enabled the exfoliation of chitosan galleries, and such host-guest mediated interactions demonstrated outstanding properties like hydrophobicity, good thermal, and solution stability due to the synergistic effects. Furthermore, the structures empowered excellent bactericidal properties against both E. coli and S. aureus as investigated by GSH loss, live/dead fluorescence microscopy, and morphological alteration on the cell surface by SEM. The work provides the benefits of disulfide-linked benzoxazines on chitosan, offering a promising avenue for general and eco-friendly usage in wound-healing and packaging material.


Assuntos
Anti-Infecciosos , Quitosana , Benzoxazinas/farmacologia , Quitosana/farmacologia , Quitosana/química , Staphylococcus aureus , Escherichia coli , Anti-Infecciosos/farmacologia , Antibacterianos/farmacologia , Antibacterianos/química , Biopolímeros/farmacologia , Biopolímeros/química
4.
Macromol Biosci ; 23(7): e2300057, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37097091

RESUMO

The major drawbacks of metal-based implants are weak osseointegration and post-operational infections. These limitations restrict the long-term use of implants that may cause severe tissue damage and replacement of the implant. Recent strategies to enhance the osseointegration process require an elaborate fabrication process and suffer from post-operative complications. To address the current challenges taking inspiration from the extracellular matrix (ECM), the current study is designed to establish enhanced osseointegration with lowered risk of infection. Natural biopolymer pectin, peptide amphiphiles, and enzyme-mimicking fullerene moieties are governed to present an ECM-like environment around the implant surfaces. This multifunctional approach promotes osseointegration via inducing biomineralization and osteoblast differentiation. Application of the biopolymer-based composite to the metal surfaces significantly enhances cellular attachment, supports the mineral deposition, and upregulates osteoblast-specific gene expression. In addition to the osteoinductive properties of the constructed layers, the inherent antimicrobial properties of multilayer coating are also used to prevent infection possibility. The reported biopolymer-artificial enzyme composite demonstrates antimicrobial activity against Escherichia coli and Bacillus subtilis as a multifunctional surface coating.


Assuntos
Anti-Infecciosos , Implantes Dentários , Osseointegração , Peptídeos/farmacologia , Anti-Infecciosos/farmacologia , Biopolímeros/farmacologia , Titânio/farmacologia , Propriedades de Superfície , Materiais Revestidos Biocompatíveis/farmacologia , Materiais Revestidos Biocompatíveis/química
5.
Int J Biol Macromol ; 234: 122944, 2023 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-36549625

RESUMO

The purpose of the current investigation was to produce a novel functional composite biodegradable film by Gellan (Gla) and Carboxymethyl cellulose (CMC) biopolymers containing rosemary essential oils (REO) and evaluate their physicochemical and antimicrobial features. The film containing 5 % REO, due to its better mechanical properties (UTS = 13.44 ± 0.30 Mpa and SB = 21.14 ± 1.15 %) compared to other emulsified samples containing REO, was selected as the optimal film. Furthermore, it had less water vapor permeability (WVP = 6.60 ± 0.31 (g/mhPa) × 10-8) in comparison to control sample (8.21 ± 0.10 (g/mhPa) × 10-8) and the best color properties among the samples. The Scanning Electron Microscopy (SEM) images didn't show the phenomenon of agglomeration and point accumulation of REO. Also, 5 % of REO contributed to the increased compactness of the film in comparison to the film without the REO. Based on the results of Fourier-transform infrared spectroscopy (FTIR) spectra, no new chemical bonds were created by adding REO to the biopolymer substrate, and the REO was well dispersed and distributed among the Gla-CMC chains throughout the film substrate. Adding 5 % REO showed antioxidant effects. Considering the antimicrobial tests, all films containing REO had antimicrobial effects against the Staphylococcus aureus, Escherichia coli, Salmonella typhimurium, and Pseudomonas fluorescens bacterial strains.


Assuntos
Anti-Infecciosos , Óleos Voláteis , Rosmarinus , Antibacterianos/farmacologia , Antibacterianos/química , Carboximetilcelulose Sódica/química , Anti-Infecciosos/farmacologia , Anti-Infecciosos/química , Biopolímeros/farmacologia , Escherichia coli , Óleos Voláteis/farmacologia , Óleos Voláteis/química , Embalagem de Alimentos/métodos
6.
Int J Mol Sci ; 23(1)2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-35008918

RESUMO

Over the years, natural-based scaffolds have presented impressive results for bone tissue engineering (BTE) application. Further, outstanding interactions have been observed during the interaction of graphene oxide (GO)-reinforced biomaterials with both specific cell cultures and injured bone during in vivo experimental conditions. This research hereby addresses the potential of fish gelatin/chitosan (GCs) hybrids reinforced with GO to support in vitro osteogenic differentiation and, further, to investigate its behavior when implanted ectopically. Standard GCs formulation was referenced against genipin (Gp) crosslinked blend and 0.5 wt.% additivated GO composite (GCsGp/GO 0.5 wt.%). Pre-osteoblasts were put in contact with these composites and induced to differentiate in vitro towards mature osteoblasts for 28 days. Specific bone makers were investigated by qPCR and immunolabeling. Next, CD1 mice models were used to assess de novo osteogenic potential by ectopic implantation in the subcutaneous dorsum pocket of the animals. After 4 weeks, alkaline phosphate (ALP) and calcium deposits together with collagen synthesis were investigated by biochemical analysis and histology, respectively. Further, ex vivo materials were studied after surgery regarding biomineralization and morphological changes by means of qualitative and quantitative methods. Furthermore, X-ray diffraction and Fourier-transform infrared spectroscopy underlined the newly fashioned material structuration by virtue of mineralized extracellular matrix. Specific bone markers determination stressed the osteogenic phenotype of the cells populating the material in vitro and successfully differentiated towards mature bone cells. In vivo results of specific histological staining assays highlighted collagen formation and calcium deposits, which were further validated by micro-CT. It was observed that the addition of 0.5 wt.% GO had an overall significant positive effect on both in vitro differentiation and in vivo bone cell recruitment in the subcutaneous region. These data support the GO bioactivity in osteogenesis mechanisms as being self-sufficient to elevate osteoblast differentiation and bone formation in ectopic sites while lacking the most common osteoinductive agents.


Assuntos
Biopolímeros/farmacologia , Diferenciação Celular , Grafite/farmacologia , Osteogênese , Células 3T3 , Fosfatase Alcalina/metabolismo , Animais , Diferenciação Celular/efeitos dos fármacos , Forma Celular/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Masculino , Camundongos , Osteogênese/efeitos dos fármacos , Porosidade , Espectroscopia de Infravermelho com Transformada de Fourier , Tela Subcutânea/efeitos dos fármacos , Alicerces Teciduais/química , Difração de Raios X , Microtomografia por Raio-X
7.
ACS Appl Bio Mater ; 4(1): 229-251, 2021 01 18.
Artigo em Inglês | MEDLINE | ID: mdl-34250454

RESUMO

Polymeric biomaterials have been used in a variety of applications, like cargo delivery and tissue scaffolding, because they are easily synthesized and can be adapted to many systems. However, there is still a need to further enhance and improve their functions to progress their use in the biomedical field. A promising solution is to modify the polymer surfaces with peptides that can increase biocompatibility, cellular interactions, and receptor targeting. In recent years, peptide modifications have been used to overcome many challenges to polymer biomaterial development. This review discusses recent progress in developing peptide-modified polymers for therapeutic applications including cell-specific targeting and tissue engineering. Furthermore, we will explore some of the most frequently studied base components of these biomaterials.


Assuntos
Biopolímeros/química , Peptídeos/química , Animais , Células Apresentadoras de Antígenos/citologia , Células Apresentadoras de Antígenos/metabolismo , Biopolímeros/metabolismo , Biopolímeros/farmacologia , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Neoplasias Encefálicas/diagnóstico por imagem , Humanos , Nanopartículas/química , Nanopartículas/metabolismo , Engenharia Tecidual , Alicerces Teciduais/química
8.
Molecules ; 26(9)2021 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-33921976

RESUMO

Self-crosslinking of Tannic acid (TA) was accomplished to obtain poly(tannic acid) (p(TA)) particles in single step, surfactant free media using sodium periodate (NaIO4) as an oxidizing agent. Almost monodisperse p(TA) particles with 981 ± 76 nm sizes and -22 ± 4 mV zeta potential value with ellipsoidal shape was obtained. Only slight degradation of p(TA) particles with 6.8 ± 0.2% was observed at pH 7.4 in PBS up to 15 days because of the irreversible covalent formation between TA units, suggesting that hydrolytic degradation is independent from the used amounts of oxidation agents. p(TA) particles were found to be non-hemolytic up to 0.5 mg/mL concentration and found not to affect blood clotting mechanism up to 2 mg/mL concentration. Antioxidant activity of p(TA) particles was investigated by total phenol content (TPC), ferric reducing antioxidant potential (FRAP), trolox equivalent antioxidant capacity (TEAC), total flavanoid content (TFC), and Fe (II) chelating activity. p(TA) particles showed strong antioxidant capability in comparison to TA molecules, except FRAP assay. The antibacterial activity of p(TA) particles was investigated by micro-dilution technique on E. coli as Gram­negative and S. aureus as Gram-positive bacteria and found that p(TA) particles are more effective on S. aureus with over 50% inhibition at 20 mg/mL concentration attained.


Assuntos
Biopolímeros/química , Biopolímeros/farmacologia , Taninos/química , Taninos/farmacologia , Antibacterianos/química , Antibacterianos/farmacologia , Antioxidantes/química , Antioxidantes/farmacologia , Materiais Biocompatíveis/química , Hidrólise , Testes de Sensibilidade Microbiana , Estrutura Molecular , Nanopartículas/química , Nanopartículas/ultraestrutura , Tamanho da Partícula , Espectroscopia de Infravermelho com Transformada de Fourier , Relação Estrutura-Atividade
9.
Int J Biol Macromol ; 178: 193-228, 2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-33631269

RESUMO

Although nanotechnology-driven drug delivery systems are relatively new, they are rapidly evolving since the nanomaterials are deployed as effective means of diagnosis and delivery of assorted therapeutic agents to targeted intracellular sites in a controlled release manner. Nanomedicine and nanoparticulate drug delivery systems are rapidly developing as they play crucial roles in the development of therapeutic strategies for various types of cancer and malignancy. Nevertheless, high costs, associated toxicity and production of complexities are some of the critical barriers for their applications. Green nanomedicines have continually been improved as one of the viable approaches towards tumor drug delivery, thus making a notable impact on which considerably affect cancer treatment. In this regard, the utilization of natural and renewable feedstocks as a starting point for the fabrication of nanosystems can considerably contribute to the development of green nanomedicines. Nanostructures and biopolymers derived from natural and biorenewable resources such as proteins, lipids, lignin, hyaluronic acid, starch, cellulose, gum, pectin, alginate, and chitosan play vital roles in the development of cancer nanotherapy, imaging and management. This review uncovers recent investigations on diverse nanoarchitectures fabricated from natural and renewable feedstocks for the controlled/sustained and targeted drug/gene delivery systems against cancers including an outlook on some of the scientific challenges and opportunities in this field. Various important natural biopolymers and nanomaterials for cancer nanotherapy are covered and the scientific challenges and opportunities in this field are reviewed.


Assuntos
Biopolímeros , Portadores de Fármacos , Nanomedicina/métodos , Nanoestruturas , Neoplasias/tratamento farmacológico , Biopolímeros/farmacologia , Biopolímeros/uso terapêutico , Portadores de Fármacos/química , Humanos , Nanoestruturas/química , Nanoestruturas/uso terapêutico
10.
Signal Transduct Target Ther ; 6(1): 63, 2021 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-33589586

RESUMO

Novel biocompatible and brush copolymers have been developed for cancer treatment using its controlled drug-release potential. Polyurethane graft on linear dextrin has been synthesized to control the hydrophilic-hydrophobic balance for regulated drug delivery. The properties of the graft copolymers have been tuned through graft density. The prepared grafts are thermally stable and mechanically strong. An injectable hydrogel has been developed by embedding the drug-loaded brush copolymers in methyl cellulose to better control the release for a prolonged period, importantly by keeping the drug release at a constant rate. Cellular studies indicate the biocompatible nature of the brush copolymers whose controlled and slow release of drug exhibit significant cytotoxic effects on cancer cells. Endocytosis of drug tagged contrast agent indicates greater transport of biologically active material inside cell as observed through cellular uptake studies. In vivo studies on melanoma mice exhibit the real efficacy of the controlled drug release from the injectable hydrogel with significant melanoma suppression without any side effects as opposed to severe toxic effects observed in conventional chemotherapy. Special application method of drug-loaded hydrogel just beneath the tumor makes this system incredibly effective through confinement. Thus, brush copolymer injectable hydrogel is a promising vehicle for control release of drug for cancer treatment in future.


Assuntos
Biopolímeros/farmacologia , Hidrogéis/farmacologia , Melanoma Experimental/tratamento farmacológico , Melanoma/tratamento farmacológico , Biopolímeros/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Meios de Contraste/farmacologia , Dextrinas/química , Sistemas de Liberação de Medicamentos , Endocitose/efeitos dos fármacos , Células HeLa , Humanos , Hidrogéis/química , Melanoma/patologia , Melanoma Experimental/genética , Poliuretanos/química
11.
Angew Chem Int Ed Engl ; 60(16): 8938-8947, 2021 04 12.
Artigo em Inglês | MEDLINE | ID: mdl-33543529

RESUMO

Ferroptosis is a new form of regulated cell death that shows promise for tumor treatment. Most current ferroptosis tumor therapies are based on the intrinsic pathological features of the malignancies, and it would be of clinical significance to develop ferroptosis-inducing strategies with improved tumor specificity and modulability. Here we report a polydopamine-based nanoplatform (FeII PDA@LAP-PEG-cRGD) for the efficient loading of Fe2+ and ß-lapachone (LAP), which could readily initiate ferroptosis in tumor cells upon treatment with near-infrared light. PDA nanostructures could generate mild hyperthermia under NIR irritation and trigger the release of the ferroptosis-inducing Fe2+ ions. The NIR-actuated photothermal effect would also activate cellular heat shock response and upregulate the downstream NQO1 via HSP70/NQO1 axis to facilitate bioreduction of the concurrently released ß-lapachone and enhance intracellular H2 O2 formation to promote the Fe2+ -mediated lipid peroxidation.


Assuntos
Antineoplásicos/farmacologia , Biopolímeros/farmacologia , Ferroptose/efeitos dos fármacos , Quelantes de Ferro/farmacologia , Nanopartículas/química , Naftoquinonas/farmacologia , Animais , Antineoplásicos/química , Biopolímeros/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Raios Infravermelhos , Quelantes de Ferro/química , Camundongos , Naftoquinonas/química , Tamanho da Partícula , Fototerapia , Propriedades de Superfície
12.
J Tissue Viability ; 30(1): 59-66, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33386237

RESUMO

AIM: Cell-based therapy has emerged as promising strategy for chronic and impaired wounds treatment. Current research is focused on developing biomaterial systems that act as a niche for mesenchymal stem cells (MSCs) to promote wound healing through paracrine molecular cascading. This study was aimed to evaluate the wound healing potential of Velgraft, a ready-to-use biodegradable artificial skin substitute, on excision wound in goats. MATERIALS AND METHODS: Twelve male goats were randomized divided in to three groups of four animals each. After infliction of surgical wound, Velgraft and Soframycin were applied on wounds of the animals of Groups II and III while Group I (sham operated) served as control. Wound diameters were measured at pre-defined time-points for determination of progressive wound healing up to 28 days. Skin sections were stained using Hematoxylin and eosin (H&E) for examining the histoarchitectural changes, Masson trichome staining for ascertaining collagen synthesis and immunohistochemistry for expression of CD31, VEGF and TGF-ß1 proteins to determine post-treatment angiogenesis in the inflicted wounds. RESULTS: Velgraft application appreciably enhanced wound closure by day 21 which was confirmed through restoration of the normal skin architecture as evident based on histopathological examination and characterized by complete regeneration of epidermal layers, collagen fibers, blood capillaries and hair follicular formation. Stimulation of angiogenesis markers was also observed at different time-points post-Velgraft application; which is suggestive of the improved angiogenesis and vasculogenesis. CONCLUSION: Velgraft facilitates wound healing by augmenting early wound closure, enhancing collagen synthesis and deposition, trichosis development and promoting revascularization and epidermal layers restoration.


Assuntos
Biopolímeros/farmacologia , Quitosana/farmacologia , Gelatina/farmacologia , Células-Tronco Mesenquimais/metabolismo , Cicatrização/efeitos dos fármacos , Análise de Variância , Animais , Biopolímeros/uso terapêutico , Quitosana/metabolismo , Quitosana/uso terapêutico , Modelos Animais de Doenças , Gelatina/metabolismo , Gelatina/uso terapêutico , Cabras , Masculino , Molécula-1 de Adesão Celular Endotelial a Plaquetas/análise , Fator de Crescimento Transformador beta1/análise , Fator A de Crescimento do Endotélio Vascular/análise
13.
Ecotoxicol Environ Saf ; 208: 111666, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33396176

RESUMO

The chemical ecology of rotifers has been little studied. A yet unknown property is presented within some monogonant rotifers, namely the ability to produce an exogenic filamentous biopolymer, named 'Rotimer'. This rotifer-specific viscoelastic fiber was observed in six different freshwater monogonants (Euchlanis dilatata, Lecane bulla, Lepadella patella, Itura aurita, Colurella adriatica and Trichocerca iernis) in exception of four species. Induction of Rotimer secretion can only be achieved by mechanically irritating rotifer ciliate with administering different types (yeast cell skeleton, denatured BSA, epoxy, Carmine or urea crystals and micro-cellulose) and sizes (approx. from 2.5 to 50 µm diameter) of inert particles, as inductors or visualization by adhering particles. The thickness of this Rotimer is 33 ± 3 nm, detected by scanning electron microscope. This material has two structural formations (fiber or gluelike) in nano dimension. The existence of the novel adherent natural product becomes visible by forming a 'Rotimer-Inductor Conglomerate' (RIC) web structure within a few minutes. The RIC-producing capacity of animals, depends on viability, is significantly modified according to physiological- (depletion), drug- (toxin or stimulator) and environmental (temperature, salt content and pH) effects. The E. dilatata-produced RIC is affected by protein disruptors but is resistant to several chemical influences and its Rotimer component has an overwhelming cell (algae, yeast and human neuroblastoma) motility inhibitory effect, associated with low toxicity. This biopolymer-secretion-capacity is protective of rotifers against human-type beta-amyloid aggregates.


Assuntos
Biopolímeros/metabolismo , Rotíferos/metabolismo , Peptídeos beta-Amiloides/farmacologia , Animais , Biopolímeros/química , Biopolímeros/farmacologia , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Água Doce/microbiologia , Humanos , Rotíferos/classificação , Rotíferos/efeitos dos fármacos , Temperatura
14.
Adv Mater ; 33(3): e2004559, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33296110

RESUMO

Surgical resection is the first-line therapy for colorectal cancer (CRC). However, for advanced CRC, the curative effect of surgical resection is limited due to either local recurrence or distal metastasis. Postoperative in situ immunotherapy, presents a promising option for preventing tumor recurrence and metastasis, owing to the fact that surgeons have unique opportunities and direct access to the surgical site. Herein, a designed biopolymer immune implant for CRC post-surgical therapy, characterized with tissue adhesion, sustained drug release, and sequential elicitation of innate immunity, adaptive immunity, and immune memory effects, is reported. With gradual release of the loaded resiquimod (R848) and anti-OX40 antibody (aOX40), the immune implant can eradicate residual tumors post-surgery (with no tumor recurrence in 150 days), inhibit the growth of distal tumors and elicit immune memory effects to resist tumor re-challenge. Immunological analysis reveal that the biopolymer immune plant treatment leads to a two-stage action, with enhanced natural killer cells (NK cells) infiltration and activation of dendritic cells (DCs) in the first several days, then a greatly increased population of infiltrating T cells, and finally immune memory effects are established. The reported biopolymer immune implants provide a valuable and clinically-relevant option for post-surgical CRC management.


Assuntos
Imunidade Adaptativa/efeitos dos fármacos , Biopolímeros/farmacologia , Neoplasias Colorretais/imunologia , Neoplasias Colorretais/terapia , Imunidade Inata/efeitos dos fármacos , Próteses e Implantes , Biopolímeros/uso terapêutico , Células Dendríticas/efeitos dos fármacos , Células Dendríticas/imunologia , Humanos , Células Matadoras Naturais/imunologia , Período Pós-Operatório
15.
Molecules ; 25(24)2020 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-33317120

RESUMO

The main objectives of this study were to evaluate the chemical constitution and allergenic potential of red propolis extract (RPE). They were evaluated, using high performance liquid chromatography (HPLC) and the release of ß-hexosaminidase, respectively. A plethora of biologically active polyphenols and the absence of allergic responses were evinced. RPE inhibited the release of ß-hexosaminidase, suggesting that the extract does not stimulate allergic responses. Additionally, the physicochemical properties and antibacterial activity of hydrogel membranes loaded with RPE were analyzed. Bio-polymeric hydrogel membranes (M) were obtained using 5% carboxymethylcellulose (M1 and M2), 1.0% of citric acid (M3) and 10% RPE (for all). Their characterization was performed using thermal analysis, Fourier transform infrared (FTIR), total phenolic content, phenol release test and, antioxidant activity through 2,2-diphenyl-1-picrylhydrazyl radical (DPPH) and Ferric Reducing Antioxidant Power (FRAP). The latter appointed to the similar antioxidant capacity of the M1, M2 and M3. The degradation profiles showed higher thermostability to M3, followed by M2 and M1. The incorporation of RPE into the matrices and the crosslinking of M3 were evinced by FTIR. There were differences in the release of phenolic compounds, with a higher release related to M1 and lower in the strongly crosslinked M3. The degradation profiles showed higher thermostability to M3, followed by M2 and M1. The antibacterial activity of the membranes was determined using the disc diffusion assay, in comparison with controls, obtained in the same way, without RPE. The membranes elicited antibacterial activity against Staphylococcus aureus and Staphylococcus epidermidis, with superior performance over M3. The hydrogel membranes loaded with RPE promote a physical barrier against bacterial skin infections and may be applied in the wound healing process.


Assuntos
Própole/química , Administração Tópica , Alérgenos/química , Animais , Antibacterianos/administração & dosagem , Antibacterianos/química , Antibacterianos/farmacologia , Antioxidantes/administração & dosagem , Antioxidantes/química , Antioxidantes/farmacologia , Bandagens , Materiais Biocompatíveis/administração & dosagem , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Biopolímeros/administração & dosagem , Biopolímeros/química , Biopolímeros/farmacologia , Brasil , Linhagem Celular , Fenômenos Químicos , Cromatografia Líquida de Alta Pressão , Composição de Medicamentos , Estabilidade de Medicamentos , Humanos , Hidrogéis , Técnicas In Vitro , Mastócitos/efeitos dos fármacos , Mastócitos/enzimologia , Mastócitos/imunologia , Membranas Artificiais , Fenóis/química , Própole/administração & dosagem , Própole/farmacologia , Ratos , Espectroscopia de Infravermelho com Transformada de Fourier , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus epidermidis/efeitos dos fármacos , Termogravimetria , beta-N-Acetil-Hexosaminidases/metabolismo
16.
J Basic Microbiol ; 60(11-12): 938-949, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33022819

RESUMO

The production of extracellular polysaccharides (EPS) by haloarchaeal members, with novel and unusual physicochemical properties, is of special importance and has the potential for extensive biotechnological exploitation. An extremely halophilic archaeon, Haloferax sp. BKW301 (GenBank Accession No. KT240044) isolated from a solar saltern of Baksal, West Bengal, India has been optimized for the production of EPS under batch culture. It produced a considerable amount (5.95 g/L) of EPS in the medium for halophiles with 15% NaCl, 3% glucose, 0.5% yeast extract, and 6% inoculum under shake flask culture at 120 rpm. The purified EPS, a homopolymer of galactose as revealed by chromatographic methods and Fourier-transform infrared spectroscopy, is noncrystalline (CIxrd , 0.82), amorphous, and could emulsify hydrocarbons like kerosene, petrol, xylene, and so forth. Moreover, the polymer is highly thermostable (up to 420°C) and displayed pseudoplastic rheology. Biologically, the EPS was able to scavenge DPPH (2,2-diphenyl-1-picrylhydrazyl) radical efficiently and inhibit the proliferation of the Huh-7 cell line at an IC50 value of 6.25 µg/ml with a Hill coefficient of 0.844. Large-scale production of this thermostable, pseudoplastic homopolysaccharide, therefore, could find suitable applications in industry and biotechnology.


Assuntos
Haloferax/metabolismo , Polissacarídeos Bacterianos/metabolismo , Técnicas de Cultura Celular por Lotes , Biopolímeros/química , Biopolímeros/isolamento & purificação , Biopolímeros/metabolismo , Biopolímeros/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Meios de Cultura , Emulsificantes , Sequestradores de Radicais Livres , Galactose , Haloferax/classificação , Haloferax/genética , Temperatura Alta , Humanos , Índia , Filogenia , Polissacarídeos Bacterianos/química , Polissacarídeos Bacterianos/isolamento & purificação , Polissacarídeos Bacterianos/farmacologia , Reologia
17.
Rev Peru Med Exp Salud Publica ; 37(2): 246-252, 2020.
Artigo em Espanhol, Inglês | MEDLINE | ID: mdl-32876212

RESUMO

OBJECTIVE: To evaluate the antitumor activity of the raw extract from biopolymers isolated from the Vibrio sp. marine bacteria in breast cancer induced by N-Methyl-N-nitrosourea (MNU) in rats. MATERIALS AND METHODS: The Vibrio sp. marine bacteria was cultured for seven days, then the raw supernatant was filtered, precipitated and concentrated. MNU was administered in a single dose of 50 mg/kg to 39 Holtzman rats and were daily treated for 9 weeks orally: G1 (n = 13): 0.1 mL/100 g of saline solution; G2 (n = 13): 20 mg/kg of raw extract from Vibrio sp. biopolymers; G3 (n = 13): 100 mg/kg of tamoxifen; G4 (n = 11) received no MNU and only 0.1 mL/100 g of saline solution. Body weight and the appearance of breast tumors identified by palpation were assessed weekly, as well as histopathological examination at the end of treatment. RESULTS: Seventy-seven percent of the rats in the G1 group developed tumors from week 7 onwards in an average of 2.2 tumors per animal; in contrast to the group treated with the raw biopolymer extract and tamoxifen; where only one rat (8%) in each group developed tumors after week nine of induction (p = 0.001). The histopathological results support that all the removed tumors correspond to breast ductal adenocarcinoma with different patterns: solid, papillary and cystic. Likewise, necrotic foci were evidenced in 30% of the tumors of the G1 group. CONCLUSION: The raw extract of biopolymers isolated from Vibrio sp. present antitumor effect in breast cancer induced in rats.


OBJETIVO: Evaluar la actividad antitumoral del extracto crudo de biopolímeros aislados de la bacteria marina Vibrio sp. en cáncer de mama inducido por N-Methyl-N-nitrosourea (MNU) en ratas. MATERIALES Y MÉTODOS: Se cultivó la bacteria marina Vibrio sp. durante siete días, luego se filtró, precipitó y concentró el sobrenadante crudo. Se administró una dosis única de MNU 50 mg/kg a 39 ratas Holtzman y fueron tratadas diariamente durante nueve semanas por vía oral: G1 (n = 13): suero fisiológico 0,1 mL/100 g; G2 (n = 13): extracto crudo de biopolímeros de Vibrio sp. 20 mg/kg; G3 (n = 13): tamoxifeno 100 mg/kg. El G4 (n = 11) solo recibió suero fisiológico 0,1 mL/100 g. Se valoró semanalmente el peso corporal y la aparición de tumores mamarios identificados mediante palpación; así como el examen histopatológico al final del tratamiento. RESULTADOS: El 77% de las ratas del grupo G1 desarrollaron tumores a partir de la séptima semana en un promedio de 2,2 tumores por cada animal; en contraste al grupo tratado con el extracto crudo de biopolímeros y tamoxifeno; donde solo una rata (8%) en cada grupo desarrolló tumores y posterior a la semana nueve de la inducción (p = 0,001). Los resultados histopatológicos sostienen que todos los tumores extirpados corresponden a adenocarcinoma ductal de mama con distintos patrones: sólido, papilar y quístico. Asimismo, se evidenciaron focos necróticos en el 30% de los tumores del grupo G1. CONCLUSIÓN: El extracto crudo de biopolímeros aislados de Vibrio sp. presentan efecto antitumoral en cáncer de mama inducido en ratas.


Assuntos
Antineoplásicos , Biopolímeros , Neoplasias Mamárias Experimentais , Vibrio , Animais , Antineoplásicos/farmacologia , Biopolímeros/isolamento & purificação , Biopolímeros/farmacologia , Feminino , Neoplasias Mamárias Experimentais/induzido quimicamente , Neoplasias Mamárias Experimentais/tratamento farmacológico , Metilnitrosoureia/toxicidade , Ratos , Ratos Sprague-Dawley , Vibrio/classificação , Vibrio/metabolismo
18.
Food Res Int ; 136: 109327, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32846526

RESUMO

Biopolymers have generated mounting interest among researchers and industrialists over the recent past. Rising consciousness on the use of eco-friendly materials as green alternatives for fossil-based biopolymers has shifted the research focus towards biopolymers. Advances in technologies have opened up new windows of opportunities to explore the potential of biopolymers. In this context, this review presents a critique on applications of biopolymers in relation to antioxidant and antimicrobial activities. Some biopolymers are reported to contain inherent antioxidant and antimicrobial properties, whereas, some biopolymers, which do not possess such inherent properties, are used as carriers for other biopolymers or additives having these properties. Modifications are often performed in order to improve the properties of biopolymers to suit them for different applications. This review aims at presenting an overview on recent advances in the use of biopolymers with special reference to their antioxidant and antimicrobial applications in various fields.


Assuntos
Anti-Infecciosos , Antioxidantes , Biopolímeros , Animais , Biodegradação Ambiental , Tecnologia Biomédica , Biopolímeros/química , Biopolímeros/farmacologia , Conservação dos Recursos Naturais , Tecnologia de Alimentos , Plantas , Tecnologia Farmacêutica
19.
Carbohydr Res ; 494: 108068, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32590200

RESUMO

Among other polysaccharides, levan is a fructan with great potential in biotechnological applications due to its functional properties. The levan has only been available in small quantities because of its high cost. Here, a levan-producing microorganism was isolated from soil and identified as Pseudomonas mandelii. TGA, SEM, FTIR, 1H NMR, 13C NMR and Zetasizer analyses were used to characterize thermal properties and the morphology of the levan. It is the first time, the levan synthesized from P. mandelii is reported as nano sized. The culture conditions were optimized. It is the most comprehensive optimization study regarding levan production of P. mandelii up to the present. The optimum conditions found for levan production were 37 °C, at pH 8, under static conditions, with 15% sucrose and 1.5% mannitol as the C sources and yeast extract as the N source. In addition, the levan production yield was calculated at optimum conditions. Antibacterial activity of levan was evaluated against bacteria and the largest zone of inhibition was observed against E. coli at a concentration of 1000 µg/mL. Antibiofilm activity of levan was evaluated, and we found that all levan concentrations inhibited biofilm formation of all microorganisms in the study. We have shown that the levan from Pseudomonas mandelii induce cytotoxicity breast (MCF-7) cells in a dose-dependent manner.


Assuntos
Antibacterianos/farmacologia , Antineoplásicos/farmacologia , Bactérias/efeitos dos fármacos , Biofilmes/efeitos dos fármacos , Biopolímeros/farmacologia , Frutanos/farmacologia , Nanopartículas/química , Antibacterianos/química , Antineoplásicos/química , Biopolímeros/química , Proliferação de Células/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Frutanos/química , Humanos , Células MCF-7 , Células Tumorais Cultivadas
20.
Rev. peru. med. exp. salud publica ; 37(2): 246-252, abr.-jun. 2020. tab, graf
Artigo em Espanhol | LILACS | ID: biblio-1127148

RESUMO

RESUMEN Objetivo: Evaluar la actividad antitumoral del extracto crudo de biopolímeros aislados de la bacteria marina Vibrio sp. en cáncer de mama inducido por N-Methyl-N-nitrosourea (MNU) en ratas. Materiales y métodos: Se cultivó la bacteria marina Vibrio sp. durante siete días, luego se filtró, precipitó y concentró el sobrenadante crudo. Se administró una dosis única de MNU 50 mg/kg a 39 ratas Holtzman y fueron tratadas diariamente durante nueve semanas por vía oral: G1 (n=13): suero fisiológico 0,1 mL/100g; G2 (n=13): extracto crudo de biopolímeros de Vibrio sp. 20 mg/kg; G3 (n=13): tamoxifeno 100 mg/kg. El G4 (n=11) solo recibió suero fisiológico 0,1 mL/100g. Se valoró semanalmente el peso corporal y la aparición de tumores mamarios identificados mediante palpación; así como el examen histopatológico al final del tratamiento. Resultados: El 77% de las ratas del grupo G1 desarrollaron tumores a partir de la séptima semana en un promedio de 2,2 tumores por cada animal; en contraste al grupo tratado con el extracto crudo de biopolímeros y tamoxifeno; donde solo una rata (8%) en cada grupo desarrolló tumores y posterior a la semana nueve de la inducción (p=0,001). Los resultados histopatológicos sostienen que todos los tumores extirpados corresponden a adenocarcinoma ductal de mama con distintos patrones: sólido, papilar y quístico. Asimismo, se evidenciaron focos necróticos en el 30% de los tumores del grupo G1. Conclusión: El extracto crudo de biopolímeros aislados de Vibrio sp. presentan efecto antitumoral en cáncer de mama inducido en ratas.


ABSTRACT Objective: To evaluate the antitumor activity of the raw extract from biopolymers isolated from the Vibrio sp. marine bacteria in breast cancer induced by N-Methyl-N-nitrosourea (MNU) in rats. Materials and methods: The Vibrio sp. marine bacteria was cultured for seven days, then the raw supernatant was filtered, precipitated and concentrated. MNU was administered in a single dose of 50 mg/kg to 39 Holtzman rats and were daily treated for 9 weeks orally: G1 (n = 13): 0.1 mL/100 g of saline solution; G2 (n = 13): 20 mg/kg of raw extract from Vibrio sp. biopolymers; G3 (n = 13): 100 mg/kg of tamoxifen; G4 (n = 11) received no MNU and only 0.1 mL/100 g of saline solution. Body weight and the appearance of breast tumors identified by palpation were assessed weekly, as well as histopathological examination at the end of treatment. Results: Seventy-seven percent of the rats in the G1 group developed tumors from week 7 onwards in an average of 2.2 tumors per animal; in contrast to the group treated with the raw biopolymer extract and tamoxifen; where only one rat (8%) in each group developed tumors after week nine of induction (p = 0.001). The histopathological results support that all the removed tumors correspond to breast ductal adenocarcinoma with different patterns: solid, papillary and cystic. Likewise, necrotic foci were evidenced in 30% of the tumors of the G1 group. Conclusion: The raw extract of biopolymers isolated from Vibrio sp. present antitumor effect in breast cancer induced in rats.


Assuntos
Animais , Ratos , Ratos , Vibrio , Biopolímeros , Neoplasias da Mama , Neoplasias Mamárias Experimentais , Antineoplásicos , Palpação , Vibrio/classificação , Vibrio/metabolismo , Biopolímeros/isolamento & purificação , Biopolímeros/farmacologia , Mama , Ratos Sprague-Dawley , Neoplasias Mamárias Experimentais/induzido quimicamente , Neoplasias Mamárias Experimentais/tratamento farmacológico , Metilnitrosoureia , Metilnitrosoureia/toxicidade , Antineoplásicos/farmacologia
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