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1.
Nanomedicine ; 40: 102486, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34748960

RESUMO

Overexpression of P-glycoprotein (P-gp) on cancer cells is a major hurdle to effectively treat tumors with multidrug resistance (MDR). The current study aimed to explore anticancer drug and P-gp inhibitor delivery as a promising strategy to efficiently treat colorectal cancer with MDR. To this end, a multidrug-loaded all-in-one nanosponge (ANS) was developed to simultaneously deliver doxorubicin (DOX), paclitaxel (PTX), and the P-gp inhibitor tetrandrine (TET), referred to as DOX/PTX/TET@ANS, without chemical conjugation. ANS with high loading content and efficiency facilitated a pH-dependent and controlled release with different profiles. Compared to free drugs and DOX/PTX@ANS, DOX/PTX/TET@ANS exhibited more effective anticancer effects on P-gp-overexpressing colorectal cancer cells and solid tumor mouse xenografts, without major toxicity. Notably, ANS composed of pluronic shell induced in vitro P-gp inhibition compared to TET, implying a synergistic anticancer effect. These findings suggest that ANS can encapsulate multiple drugs to efficiently deliver chemotherapy, particularly in MDR tumors.


Assuntos
Neoplasias , Poloxâmero , Membro 1 da Subfamília B de Cassetes de Ligação de ATP , Animais , Linhagem Celular Tumoral , Doxorrubicina/farmacologia , Doxorrubicina/uso terapêutico , Resistência a Múltiplos Medicamentos , Resistencia a Medicamentos Antineoplásicos , Humanos , Camundongos , Poloxâmero/farmacologia
2.
Bioconjug Chem ; 31(10): 2456-2464, 2020 10 21.
Artigo em Inglês | MEDLINE | ID: mdl-33034448

RESUMO

An inverse-electron-demand Diels-Alder (IEDDA) reaction using genetically encoded tetrazine variants enables rapid bioconjugation for diverse applications in vitro and in cellulo. However, in vivo bioconjugation using genetically encoded tetrazine variants is challenging, because the IEDDA coupling reaction competes with rapid elimination of reaction partners in vivo. Here, we tested the hypothesis that a genetically encoded phenylalanine analogue containing a hydrogen-substituted tetrazine (frTet) would increase the IEDDA reaction rate, thereby allowing for successful bioconjugation in vivo. We found that the in vitro IEDDA reaction rate of superfolder green fluorescent protein (sfGFP) containing frTet (sfGFP-frTet) was 12-fold greater than that of sfGFP containing methyl-substituted tetrazine (sfGFP-Tet_v2.0). Additionally, sfGFP variants encapsulated with chitosan-modified, pluronic-based nanocarriers were delivered into nude mice or tumor-bearing mice for in vivo imaging. The in vivo-delivered sfGFP-frTet exhibited almost complete fluorescence recovery upon addition of trans-cyclooctene via the IEDDA reaction within 2 h, whereas sfGFP-Tet_v2.0 did not show substantial fluorescence recovery. These results demonstrated that the genetically encoded frTet allows an almost complete IEDDA reaction in vivo upon addition of trans-cyclooctene, enabling temporal control of in vivo bioconjugation in a very high yield.


Assuntos
Reação de Cicloadição/métodos , Ciclo-Octanos/química , Corantes Fluorescentes/química , Proteínas de Fluorescência Verde/química , Compostos Heterocíclicos com 1 Anel/química , Fenilalanina/análogos & derivados , Animais , Elétrons , Proteínas de Fluorescência Verde/genética , Masculino , Camundongos , Camundongos Nus , Fenilalanina/genética
3.
Biomacromolecules ; 17(5): 1811-7, 2016 05 09.
Artigo em Inglês | MEDLINE | ID: mdl-27050863

RESUMO

Polyethylene glycol (PEG) has been widely used as a serum half-life extender of therapeutic proteins. However, due to immune responses and low degradability of PEG, developing serum half-life extender alternatives to PEG is required. Human serum albumin (HSA) has several beneficial features as a serum half-life extender, including a very long serum half-life, good degradability, and low immune responses. In order to further evaluate the efficacy of HSA, we compared the extent of serum half-life extension of a target protein, superfolder green fluorescent protein (sfGFP), upon HSA conjugation with PEG conjugation side-by-side. Combination of site-specific incorporation of p-azido-l-phenylalanine into sfGFP and copper-free click chemistry achieved the site-specific conjugation of a single HSA, 20 kDa PEG, or 30 kDa PEG to sfGFP. These sfGFP conjugates exhibited the fluorescence comparable to or even greater than that of wild-type sfGFP (sfGFP-WT). In mice, HSA-conjugation to sfGFP extended the serum half-life 9.0 times compared to that of unmodified sfGFP, which is comparable to those of PEG-conjugated sfGFPs (7.3 times for 20 kDa PEG and 9.5 times for 30 kDa PEG). These results clearly demonstrated that HSA was as effective as PEG in extending the serum half-life of a target protein. Therefore, with the additional favorable features, HSA is a good serum half-life extender of a (therapeutic) protein as an alternative to PEG.


Assuntos
Proteínas de Fluorescência Verde/química , Proteínas de Fluorescência Verde/metabolismo , Fenilalanina/química , Polietilenoglicóis/química , Albumina Sérica/química , Animais , Meia-Vida , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C
4.
Biomacromolecules ; 16(2): 497-506, 2015 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-25539413

RESUMO

An in situ heparin-based forming hydrogel that cures under visible-light is formulated using eosin Y as a photoinitiator with triethanolamine as an electron donor to initiate reaction of thiolated-heparin with acrylate-ended poly(ethylene glycol). Formulations and irradiation conditions are presented for control of heparin content (1.6 to 3.3% w/v), modulus (100-10,000 Pa), and gelation time (30-600 s). Encapsulation of 3T3 fibroblasts in the hydrogel gave over 96% viability for all conditions examined. In vitro characterization of epidermal growth factor released from the hydrogel confirmed that the growth factor remains bioactive. The ability to deliver growth factors, fast gelation kinetics under visible light, and independent control of physical and biochemical properties makes this system a promising candidate for use in regenerative medicine. In particular, irradiation conditions that achieve gelation in 150s are compatible with the stringent light exposure limits of the retina, which affords a wide safety margin for use with other tissues.


Assuntos
Acrilatos/efeitos da radiação , Heparina/efeitos da radiação , Hidrogéis/efeitos da radiação , Luz , Compostos de Sulfidrila/efeitos da radiação , Acrilatos/química , Acrilatos/farmacologia , Animais , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Reagentes de Ligações Cruzadas/química , Reagentes de Ligações Cruzadas/farmacologia , Reagentes de Ligações Cruzadas/efeitos da radiação , Heparina/química , Heparina/farmacologia , Hidrogéis/química , Hidrogéis/farmacologia , Camundongos , Células NIH 3T3 , Polimerização , Compostos de Sulfidrila/química , Compostos de Sulfidrila/farmacologia
5.
Nanomedicine ; 11(2): 359-68, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25262581

RESUMO

In this study, we prepared iron oxide nanoparticle and doxorubicin-loaded multifunctional nano-carrier (IONP/DOX-MFNC), capable of simultaneous cancer targeting via a herceptin monoclonal antibody, controlled anticancer drug delivery, as well as imaging modalities of magnetic resonance imaging (MRI) and near-infrared fluorescence (NIRF) imaging. IONP and DOX were efficiently loaded into the nano-carrier, and a desirable pH-responsive release of DOX was achieved by MFNC. The nano-carrier showed much higher cellular uptake and stronger cytotoxicity to HER2 overexpressed SK-BR-3 (human breast cancer cells) than MCF-7, a negative control cell, suggesting specific cancer targeting via HER2 receptor. In an in vivo tumor xenograft model, IONP/DOX-MFNC showed higher tumor uptake and significantly enhanced tumor regression than the nano-carrier without the antibody. Thus, DOX-loaded, multi-functional nano-carrier with HER2 antibody was effective for both imaging and therapy, showing the potential for early stage cancer diagnosis and simultaneous therapy. FROM THE CLINICAL EDITOR: In this study, efficacy -both for imaging and treatment - was demonstrated on a doxorubicin and iron oxide nanoparticle loaded multifunctional nano-carrier with HER2 antibody to show the potential for early stage cancer diagnosis and simultaneous therapy.


Assuntos
Anticorpos Monoclonais Humanizados/administração & dosagem , Neoplasias da Mama/tratamento farmacológico , Doxorrubicina/administração & dosagem , Sistemas de Liberação de Medicamentos , Compostos Férricos/administração & dosagem , Animais , Anticorpos Monoclonais/administração & dosagem , Anticorpos Monoclonais/química , Anticorpos Monoclonais Humanizados/química , Antineoplásicos , Neoplasias da Mama/patologia , Meios de Contraste , Doxorrubicina/química , Feminino , Compostos Férricos/química , Humanos , Células MCF-7 , Imageamento por Ressonância Magnética , Nanopartículas Metálicas/administração & dosagem , Nanopartículas Metálicas/química , Camundongos , Receptor ErbB-2/imunologia , Receptor ErbB-2/uso terapêutico , Trastuzumab , Ensaios Antitumorais Modelo de Xenoenxerto
6.
RSC Adv ; 14(3): 1866-1874, 2024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-38192324

RESUMO

Osseointegration remains one of the major challenges in the success of bone-related implants. Recently, polyetheretherketone (PEEK) has emerged as an alternative material in orthopedic and dental applications due to its bone-mimicking mechanical properties. However, its bioinertness resulting in poor osseointegration has limited its potential application. So, the surface modification of PEEK with bone morphogenetic protein-2 (BMP-2) can be a potential approach for improving osseointegration. In this study, we proposed the chemical modification of heparin onto PEEK through an environmentally benign method to exploit the BMP-2 binding affinity of heparin. The heparin was successfully functionalized on the PEEK surface via a combination of ozone and UV treatment without using organic solvents or chemicals. Furthermore, BMP-2 was efficiently immobilized on PEEK and exhibited a sustained release of BMP-2 compared to the pristine PEEK with enhancement of bioactivity in terms of proliferation as well as osteogenic differentiation of MG-63. The significant synergistic effect of BMP-2 and heparin grafting on osteogenic differentiation of MG-63 was observed. Overall, we demonstrated a relatively safe method where no harsh chemical reagent or organic solvent was involved in the process of heparin grafting onto PEEK. The BMP-2 loaded, heparin-grafted PEEK could serve as a potential platform for osseointegration improvement of PEEK-based bone implants.

7.
Biophys Rev (Melville) ; 5(2): 021306, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38846007

RESUMO

Over the past few decades, extensive research has explored the development of supportive scaffold materials for in vitro hepatic cell culture, to effectively mimic in vivo microenvironments. It is crucial for hepatic disease modeling, drug screening, and therapeutic evaluations, considering the ethical concerns and practical challenges associated with in vivo experiments. This review offers a comprehensive perspective on hepatic cell culture using bioscaffolds by encompassing all stages of hepatic diseases-from a healthy liver to fibrosis and hepatocellular carcinoma (HCC)-with a specific focus on matrix stiffness. This review begins by providing physiological and functional overviews of the liver. Subsequently, it explores hepatic cellular behaviors dependent on matrix stiffness from previous reports. For hepatic cell activities, softer matrices showed significant advantages over stiffer ones in terms of cell proliferation, migration, and hepatic functions. Conversely, stiffer matrices induced myofibroblastic activation of hepatic stellate cells, contributing to the further progression of fibrosis. Elevated matrix stiffness also correlates with HCC by increasing proliferation, epithelial-mesenchymal transition, metastasis, and drug resistance of HCC cells. In addition, we provide quantitative information on available data to offer valuable perspectives for refining the preparation and development of matrices for hepatic tissue engineering. We also suggest directions for further research on this topic.

8.
ACS Appl Mater Interfaces ; 16(3): 3031-3041, 2024 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-38224063

RESUMO

This research presents a simple but general method to prepare water-soluble-polymer-based superabsorbent hydrogels with predefined microscale geometries and controlled swelling properties. Unlike conventional hydrogel preparation methods based on bulk solution-phase cross-linking, poly(vinyl alcohol) is homogeneously mixed with polymer-based cross-linkers in the solution phase and thermally cross-linked in the solid phase after drying; the degree of cross-linking is modulated by controlling the cross-linker concentration, pH, and/or thermal annealing conditions. After the shape definition process, cross-linked films or electrospun nanofibers are treated with sulfuric acid to weaken hydrogen bonds and introduce sulfate functionality in polymer crystallites. The resultant superabsorbent hydrogels exhibit an isotropic expansion of the predefined geometry and tunable swelling properties. Particularly, hydrogel microfibers exhibit excellent optical transparency, good biocompatibility, large porosity, and controlled cell adhesion, leading to versatile 3D cell culture scaffolds that not only support immortalized cell lines and primary neurons but also enable stiffness-modulated cell adhesion studies.

9.
Adv Healthc Mater ; : e2400693, 2024 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-38795005

RESUMO

Collagen is a complex, large protein molecule that presents a challenge in delivering it to the skin due to its size and intricate structure. However, conventional collagen delivery methods are either invasive or may affect the protein's structural integrity. This study introduces a novel approach involving the encapsulation of collagen monomers within zwitterionic nanoliposomes, termed Lip-Cols, and the controlled formation of collagen fibrils through electric fields (EF) stimulation. The results reveal the self-assembly process of Lip-Cols through electroporation and a pH gradient change uniquely triggered by EF, leading to the alignment and aggregation of Lip-Cols on the electrode interface. Notably, Lip-Cols exhibit the capability to direct the orientation of collagen fibrils within human dermal fibroblasts. In conjunction with EF, Lip-Cols can deliver collagen into the dermal layer and increase the collagen amount in the skin. The findings provide novel insights into the directed formation of collagen fibrils via electrical stimulation and the potential of Lip-Cols as a non-invasive drug delivery system for anti-aging applications.

10.
Biomater Res ; 27(1): 28, 2023 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-37038209

RESUMO

BACKGROUND: Cellular infiltration and angiogenesis into implanted biomaterial scaffolds are crucial for successful host tissue integration and tissue regeneration. Cellulose nanocrystal (CNC) is a nano-sized cellulose derivative, which can form an injectable physical gel with salts. Sulfate groups of sulfated CNC (CNC-S) can act as a binding domain to various growth factors and cytokines with a heparin-binding domain for sustained release of them. Vascular endothelial growth factor (VEGF) can promote the proliferation of endothelial cells and angiogenesis. In this study, VEGF-loaded CNC-S hydrogel was evaluated as an injectable scaffold that can induce cellular infiltration and angiogenesis. METHODS: CNC-S was hydrolyzed to get desulfated CNC (CNC-DS), which was used as a negative control group against CNC-S. Both CNC-S and CNC-DS hydrogels were prepared and compared in terms of biocompatibility and VEGF release. The hydrogels with or without VEGF loading were subcutaneously injected into mice to evaluate the biocompatibility, cellular infiltration, and angiogenesis induction of the hydrogels. RESULTS: Both hydrogels possessed similar stability and shear-thinning behavior to be applicable as injectable hydrogels. However, CNC-S hydrogel showed sustained release (until 8 weeks) of VEGF whereas CNC-DS showed a very fast release of VEGF with a large burst. Subcutaneously injected CNC-S hydrogel showed much enhanced cellular infiltration as well as better biocompatibility with milder foreign body response than CNC-DS hydrogel. Furthermore, VEGF-loaded CNC-S hydrogel induced significant angiogenesis inside the hydrogel whereas VEGF-loaded CNC-DS did not. CONCLUSION: CNC-S possesses good properties as a biomaterial including injectability, biocompatibility, and allowing cellular infiltration and sustained release of growth factors. VEGF-loaded CNC-S hydrogel exhibited efficient angiogenesis inside the hydrogel. The sulfate group of CNC-S was a key for good biocompatibility and the biological activities of VEGF-loaded CNC hydrogel.

11.
Adv Drug Deliv Rev ; 203: 115119, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37898338

RESUMO

Inflammation is prevalent and inevitable in daily life but can generally be accommodated by the immune systems. However, incapable self-healing and persistent inflammation can progress to chronic inflammation, leading to prevalent or fatal chronic diseases. This review comprehensively covers the topic of emerging drug delivery systems (DDSs) for the treatment of chronic inflammatory diseases (CIDs). First, we introduce the basic biology of the chronic inflammatory process and provide an overview of the main CIDs of the major organs. Next, up-to-date information on various DDSs and the associated strategies for ensuring targeted delivery and stimuli-responsiveness applied to CIDs are discussed extensively. The implementation of traditional routes of drug administration to maximize their therapeutic effects against CIDs is then summarized. Finally, perspectives on future DDSs against CIDs are presented.


Assuntos
Sistemas de Liberação de Medicamentos , Inflamação , Humanos , Inflamação/tratamento farmacológico , Doença Crônica
12.
ACS Appl Mater Interfaces ; 15(33): 39117-39126, 2023 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-37551880

RESUMO

Conjugated polymer nanoparticles (CP NPs) that could absorb the first near-infrared (NIR-I) window have emerged as highly desirable therapeutic nanomaterials. Here, a quinoidal-conjugated polymer (QCP), termed PQ, was developed as a novel class of therapeutic agents for photothermal therapy (PTT). Owing to its intrinsic quinoid structure, PQ exhibits molecular planarity and π-electron overlap along the conjugated backbone, endowing it with a narrow band gap, NIR-I absorption, and diradical features. The obtained PQ was coated with a poly(ethylene glycol) (PEG) moiety, affording nanosized and water-dispersed PQ nanoparticles (PQ NPs), which consequently show a high photothermal conversion efficiency (PCE) of 63.2%, good photostability, and apparent therapeutic efficacy for both in vitro and in vivo PTTs under an 808 nm laser irradiation. This study demonstrates that QCPs are promising active agents for noninvasive anticancer therapy using NIR-I light.


Assuntos
Nanopartículas , Fototerapia , Linhagem Celular Tumoral , Polímeros/farmacologia , Polímeros/química , Nanopartículas/uso terapêutico , Nanopartículas/química
13.
Carbohydr Polym ; 316: 121088, 2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37321716

RESUMO

Nanozymes have prominent catalytic activities with high stability as a substitute for unstable and expensive natural enzymes. However, most nanozymes are metal/inorganic nanomaterials, facing difficulty in clinical translation due to their unproven biosafety and limited biodegradability issues. Hemin, an organometallic porphyrin, was newly found to possess superoxide dismutase (SOD) mimetic activity along with previously known catalase (CAT) mimetic activity. However, hemin has poor bioavailability due to its low water solubility. Therefore, a highly biocompatible and biodegradable organic-based nanozyme system with SOD/CAT mimetic cascade reaction activity was developed by conjugating hemin to heparin (HepH) or chitosan (CS-H). Between them, Hep-H formed a smaller (<50 nm) and more stable self-assembled nanostructure and even possessed much higher and more stable SOD and CAT activities as well as the cascade reaction activity compared to CS-H and free hemin. Hep-H also showed a better cell protection effect against reactive oxygen species (ROS) compared to CS-H and hemin in vitro. Furthermore, Hep-H was selectively delivered to the injured kidney upon intravenous administration at the analysis time point (24 h) and exhibited excellent therapeutic effects on an acute kidney injury model by efficiently removing ROS, reducing inflammation, and minimizing structural and functional damage to the kidney.


Assuntos
Injúria Renal Aguda , Hemina , Humanos , Catalase , Hemina/química , Espécies Reativas de Oxigênio , Heparina , Antioxidantes , Superóxido Dismutase , Injúria Renal Aguda/induzido quimicamente , Injúria Renal Aguda/tratamento farmacológico
14.
Biomedicines ; 11(5)2023 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-37239107

RESUMO

This study explores the therapeutic efficacy of heparin-based hydrogel micropatches containing human adipose-derived stem cells (hASCs) in treating neuropathic pain caused by nerve damage. Our results showed that hASCs exhibited neuroregenerative and pain-relieving effects when used with heparin-based hydrogel micropatches in the neuropathic pain animal model. The use of this combination also produced enhanced cell viability and nerve regeneration. We conducted various neurological behavioral tests, dynamic plantar tests, histological examinations, and neuroelectrophysiological examinations to confirm the therapeutic effect. Our findings suggest that this approach could maximize therapeutic efficacy and improve the quality of life for patients suffering from neuropathic pain.

15.
Mater Today Bio ; 22: 100774, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37664795

RESUMO

Ferrocene-based nanoparticles have garnered interest as reactive oxygen species (ROS)-responsive nanocarriers of anticancer drugs and imaging agents. However, their biomedical applications remain limited due to their poor physiological stability. PEGylation of nanocarriers improves their stability and biocompatibility. In this study, we aimed to develop novel PEG-ferrocene nanoparticles (PFNPs) with enhanced stability and ROS responsiveness for the delivery of paclitaxel (PTX) and imaging agents. PEGylation improved the stability of ferrocene nanoparticles, inhibiting their ROS-responsive destruction. Several PEG-ferrocene polymers containing different molar ratios of methacrylic acid and poly (ethylene glycol) methyl ether methacrylate was designed for optimization. ROS-responsive polymers with optimal monomer ratios were self-assembled into PFNPs with enhanced stability. The PFNPs distended, effectively releasing encapsulated PTX and imaging agents within 8 h in the presence of ROS. Furthermore, they remained stable, with no changes in their hydrodynamic diameters or polydispersity indexes after storage in an aqueous solution and biological buffer. The accumulation of PFNPs in a tumor model in vivo was 15-fold higher than a free dye. PTX-loaded PFNPs showed a substantial tumor-suppression effect, reducing tumor size to approximately 18% of that in the corresponding control group. These findings suggest a promising application of ROS-responsive PFNPs in tumor treatment as biocompatible nanocarriers of anticancer drugs and imaging agents.

16.
Biomacromolecules ; 13(8): 2287-98, 2012 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-22758918

RESUMO

Delivering isolated chondrocytes with matrix is a promising approach to promote the cartilage repair. The present study attempted to combine the advantages of porous scaffold and hydrogel in delivering chondrocytes to partial-thickness cartilage defects. An electrospun, gelatin-incorporated PLCL scaffold mechanically similar to natural cartilage was fabricated, and chondrocytes were seeded using an injectable heparin-based hydrogel for efficient cell seeding. The scaffold/hydrogel composite showed more enhanced expression of chondrogenic genes and production of GAGs than those prepared without hydrogel. In addition, significant cartilage formation showing good integration with surrounding, similar to natural cartilage, was observed by scaffold/hydrogel composite system in partial-thickness defects of rabbit knees while no regeneration was observed in control defects. Although no exogenous chondrogenic factors were added, it was evident that the scaffold/hydrogel composite system was highly effective and better than the scaffold alone system without hydrogel for cartilage regeneration both in vitro and in vivo.


Assuntos
Heparina/química , Cartilagem Hialina/fisiologia , Hidrogéis/síntese química , Poliésteres/química , Próteses e Implantes , Regeneração , Alicerces Teciduais , Animais , Proliferação de Células , Células Cultivadas , Condrócitos/metabolismo , Condrócitos/fisiologia , Condrócitos/transplante , Colágeno Tipo II/genética , Colágeno Tipo II/metabolismo , Força Compressiva , Expressão Gênica , Glicosaminoglicanos/metabolismo , Cartilagem Hialina/patologia , Articulação do Joelho/metabolismo , Articulação do Joelho/patologia , Articulação do Joelho/fisiopatologia , Nanofibras/química , Porosidade , Coelhos , Engenharia Tecidual , Fator de Crescimento Transformador beta1/metabolismo
17.
Anal Bioanal Chem ; 402(5): 1847-56, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22203370

RESUMO

This paper describes a novel platform that utilizes micropatterning and electrochemistry to release cells-on-hydrogel microstructures from conductive indium tin oxide (ITO) substrates. In this approach, UV photopolymerization was employed to micropattern heparin-based hydrogels onto glass substrates containing ITO electrodes. ITO/glass substrates were first functionalized with acrylated silane to promote attachment of hydrogel structures. The surfaces containing hydrogel micropatterns were further functionalized with poly(ethylene glycol) thiol, rendering the regions around the hydrogel structures non-fouling to proteins and cells. After incubating surfaces with collagen (I), primary rat hepatocytes were shown to selectively attach on top of the hydrogel and not on surrounding glass/ITO regions. Electrical activation of specific ITO electrodes (-1.8 V vs. Ag/AgCl reference) was then used to release cells-on-hydrogel microstructures from the substrate. Immunostaining and reverse transcription polymerase chain reaction analysis of albumin, an important indicator of hepatic function, showed that the hepatocyte-on-hydrogel microstructures released from the surface maintained their function at levels similar to hepatocytes remaining on the culture substrate. In the future, switchable conductive substrates described here may be to collect cell samples at different time points and may also be used for harvesting cell-carrying vehicles for transplantation studies.


Assuntos
Eletroquímica/métodos , Hepatócitos , Hidrogéis/química , Compostos de Estanho/química , Eletrodos , Vidro , Células Hep G2 , Heparina/química , Humanos , Polietilenoglicóis/química , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Propriedades de Superfície , Raios Ultravioleta
18.
Carbohydr Polym ; 280: 119026, 2022 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-35027128

RESUMO

Cell microencapsulation is a process to entrap viable and functional cells within a biocompatible and semi-permeable matrix to provide a favorable microenvironment to the cells. Cellulose nanofiber (CNF), a low-cost and sustainable cellulose-derived natural polymer, has been studied as a matrix for 3D stem cell culture in the form of a bulk hydrogel. Here, the preparation of CNF microbeads for the long-term 3D culture of human adipose-derived stem cells (hADSCs) was demonstrated. Furthermore, hyaluronic acid (HA) was physically incorporated into the stem cell encapsulated CNF microbeads with various molecular weights and concentrations to investigate its potential in enhancing the cellular bioactivities. The beneficial effects of HA incorporation on encapsulated cells were significant compared to CNF microbeads, especially with 700 kDa molecular weight and 0.2% in concentration in terms of cell proliferation (~2 times) and VEGF secretion (~2 times) while maintaining their stemness. All the results demonstrated that the HA-incorporated CNF microbeads could serve as a promising microencapsulation matrix for hADSCs.


Assuntos
Encapsulamento de Células , Celulose , Ácido Hialurônico/química , Células-Tronco Mesenquimais/fisiologia , Microesferas , Nanofibras , Adipogenia , Técnicas de Cultura de Células , Proliferação de Células , Forma Celular , Sobrevivência Celular , Células Cultivadas , Humanos , Hidrogéis , Células-Tronco Mesenquimais/citologia , Peso Molecular , Fator A de Crescimento do Endotélio Vascular/metabolismo
19.
Mater Sci Eng C Mater Biol Appl ; 135: 112671, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35581060

RESUMO

Glycosaminoglycans (GAGs) are essential for cell-cell and cell-ECM interactions. Unique structures of GAGs provide high affinities to specific cell receptors. Especially, hyaluronic acid (HA), chondroitin sulfate (CS), and heparin are known to have affinities to the liver sinusoidal endothelial cells (LSECs), so they have been utilized as a ligand for liver targeting nanoparticle systems. In this study, we compared different GAGs as a targeted cell delivery ligand by using lipid-conjugated GAGs. Conjugated lipids of GAGs could provide a stable coating over 2 days on the surface of human adipose-derived stem cells (hADSCs) by physical insertion. The hADSCs coated by different GAGs were intravenously injected into mice, and the biodistribution of cells was analyzed by an In Vivo Imaging System (IVIS) to compare the effect of various GAGs on the modulation of biodistribution of stem cells. The results showed that all three GAGs could provide less entrapment in the lung but enhanced accumulation in the liver and spleen. Especially, HA- and heparin coating on hADSCs showed a 1.5-fold higher accumulation than CS-coating on hADSCs in the liver and spleen. Thus, lipid-conjugated HA and heparin are potentially useful coating materials for the liver or spleen-targeted delivery system of therapeutic stem cells.


Assuntos
Células Endoteliais , Glicosaminoglicanos , Administração Intravenosa , Animais , Sulfatos de Condroitina/química , Sulfatos de Condroitina/farmacologia , Glicosaminoglicanos/química , Heparina/química , Heparina/farmacologia , Humanos , Ácido Hialurônico/química , Ácido Hialurônico/farmacologia , Ligantes , Lipídeos , Camundongos , Células-Tronco , Distribuição Tecidual
20.
J Control Release ; 344: 160-172, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35247490

RESUMO

Nanoreactors for scavenging reactive oxygen species (ROS), a major factor in inflammatory diseases, can reduce overproduced ROS, and thus can prevent further progress of the diseases or facilitate the regeneration of damaged inflamed tissues. Herein, we designed a pluronic-based nanocarrier loaded with dual antioxidant enzymes present in vivo (superoxide dismutase (SOD) and catalase (CAT)) as a nanoreactor system for the regeneration of inflammatory tissue. The catalytic activity of each enzyme was enhanced by loading it into the nanocarrier. More importantly, the nanocarrier could enhance the cascade reaction between SOD and CAT, which converts the superoxide anion to oxygen. The synergistic anti-inflammatory effect of the nanoreactor based on the cascade reaction was verified in vitro. Furthermore, in an inflammatory bowel disease (IBD) mouse model, the dual enzyme (SOD/CAT)-loaded nanocarrier could result in significantly enhanced tissue regeneration and notably alleviated inflammation activities upon intravenous administration of them compared to other control groups, including single enzyme (SOD or CAT)-loaded nanocarrier and the free mixture of both enzymes without the nanocarrier. Thus, the efficacy of the nanoreactor for the cascade reaction on tissue regeneration in vivo was proved. Accordingly, the nanoreactor could be applied for tissue regeneration therapy against various inflammatory diseases.


Assuntos
Antioxidantes , Nanotecnologia , Regeneração , Superóxido Dismutase , Animais , Catalase , Camundongos , Espécies Reativas de Oxigênio
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