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1.
Pharmaceutics ; 16(4)2024 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-38675224

RESUMO

Lipid nanoparticles (LNPs) have established their position as nonviral vectors for gene therapy. Tremendous efforts have been made to modulate the properties of LNPs to unleash their full clinical potential. Among the strategies being pursued, the layer-by-layer (LbL) technique has gained considerable attention in the biomedical field. Illuminated by our previous work, here we investigate if the LbL approach could be used to modify the LNP cores formulated with three different ionizable lipids: DODMA, MC3, and DODAP. Additionally, we wondered if more than three layers could be loaded onto LNPs without disrupting their gene transfection ability. Taking advantage of physicochemical analysis, as well as uptake and gene silencing studies, we demonstrate the feasibility of modifying the surface of LNPs with the LbL assembly. Precisely, we successfully modified three different LNPs using the layer-by-layer strategy which abrogated luciferase activity in vitro. Additionally, we constructed a 5×-layered HA-LNP containing the MC3 ionizable lipid which outperformed the 3×-layered counterpart in transfecting miRNA-181-5p to the pediatric GBM cell line, as a proof-of-concept in vitro experiment. The method used herein has been proven reproducible, of easy modification to adapt to different ionizable lipid-containing LNPs, and holds great potential for the translation of RNA-based therapeutic strategies.

2.
Biomaterials ; 302: 122341, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37778056

RESUMO

Glioblastoma multiforme (GBM) is the most common and lethal primary brain cancer. Current pharmacological interventions marginally increase the 12-month overall survival of patients with GBM. Among the novel therapeutic strategies being pursued, micro-RNAs, a class of non-coding RNAs, are receiving considerable attention for their regulation of several pathways implicated in tumorigenesis and survival. Notably, microRNA-181a-5p (miR-181a) has consistently been reported to be downregulated in GBM clinical samples, and its overexpression negatively affects tumor growth both in vitro and in vivo. To improve the delivery of miR-181a to GBM cells, we sought to develop a modified lipid-based nanocarrier capable of encapsulating and delivering miR-181a to GBM cells in vitro and in vivo. Optimized ionizable-lipid containing lipid nanoparticles (LNP) were constructed by covering the miR-181a-loaded LNP with alternating layers of miR-181a, poly-l-arginine and hyaluronic acid through the layer-by-layer technique. The resulting hyaluronan-decorated lipid nanoparticles (HA-LNP) targeted GBM cells more efficiently than non-modified LNP and mediated siRNA and miRNA transfection in vitro. Finally, delivery of miR-181a by HA-LNP induced significant cellular death of U87 GBM cells in vitro and delayed tumor growth in an in vivo subcutaneous tumor model.


Assuntos
Glioblastoma , MicroRNAs , Humanos , Glioblastoma/genética , Glioblastoma/terapia , Glioblastoma/metabolismo , Ácido Hialurônico , Linhagem Celular Tumoral , MicroRNAs/genética , MicroRNAs/metabolismo , Lipídeos , Proliferação de Células
3.
Sci Rep ; 13(1): 16443, 2023 09 30.
Artigo em Inglês | MEDLINE | ID: mdl-37777587

RESUMO

Neuroblastoma, the most common type of pediatric extracranial solid tumor, causes 10% of childhood cancer deaths. Despite intensive multimodal treatment, the outcomes of high-risk neuroblastoma remain poor. We urgently need to develop new therapies with safe long-term toxicity profiles for rapid testing in clinical trials. Drug repurposing is a promising approach to meet these needs. Here, we investigated disulfiram, a safe and successful chronic alcoholism treatment with known anticancer and epigenetic effects. Disulfiram efficiently induced cell cycle arrest and decreased the viability of six human neuroblastoma cell lines at half-maximal inhibitory concentrations up to 20 times lower than its peak clinical plasma level in patients treated for chronic alcoholism. Disulfiram shifted neuroblastoma transcriptome, decreasing MYCN levels and activating neuronal differentiation. Consistently, disulfiram significantly reduced the protein level of lysine acetyltransferase 2A (KAT2A), drastically reducing acetylation of its target residues on histone H3. To investigate disulfiram's anticancer effects in an in vivo model of high-risk neuroblastoma, we developed a disulfiram-loaded emulsion to deliver the highly liposoluble drug. Treatment with the emulsion significantly delayed neuroblastoma progression in mice. These results identify KAT2A as a novel target of disulfiram, which directly impacts neuroblastoma epigenetics and is a promising candidate for repurposing to treat pediatric neuroblastoma.


Assuntos
Dissulfiram , Neuroblastoma , Animais , Criança , Humanos , Camundongos , Dissuasores de Álcool/farmacologia , Dissuasores de Álcool/uso terapêutico , Linhagem Celular Tumoral , Dissulfiram/farmacologia , Dissulfiram/uso terapêutico , Regulação para Baixo , Reposicionamento de Medicamentos , Emulsões/uso terapêutico , Histona Acetiltransferases/efeitos dos fármacos , Neuroblastoma/tratamento farmacológico , Neuroblastoma/genética
4.
Langmuir ; 39(34): 12235-12247, 2023 08 29.
Artigo em Inglês | MEDLINE | ID: mdl-37581531

RESUMO

We compared different biofunctionalization strategies for immobilizing trastuzumab, an IgG targeting the HER2 biomarker, onto 100 nm spherical gold nanoparticles because of the E/K coiled-coil peptide heterodimer. First, Kcoil peptides were grafted onto the gold surface while their Ecoil partners were genetically encoded at the C-terminus of trastuzumab's Fc region, allowing for a strong and specific interaction between the antibodies and the nanoparticles. Gold nanoparticles with no Kcoil peptides on their surface were also produced to immobilize Ecoil-tagged trastuzumab antibodies via the specific adsorption of their negatively charged Ecoil tags on the positively charged gold surface. Finally, the nonspecific adsorption of wild-type trastuzumab on the gold surface was also assessed, with and without Kcoil peptides grafted on it beforehand. We developed a thorough workflow to systematically compare the immobilization strategies regarding the stability of nanoparticles, antibody coverage, and ability to specifically bind to HER2-positive breast cancer cells. All nanoparticles were highly monodisperse and retained their localized surface plasmon resonance properties after biofunctionalization. A significant increase in the amount of immobilized antibodies was observed with the two oriented coil-based strategies compared to nonspecific adsorption. Finally, all biofunctionalization strategies allowed for the detection of HER2-positive breast cancer cells, but among the investigated approaches, we recommend using the E/K coiled-coil-based strategy for gold nanoparticle biofunctionalization because it allows for the qualitative and quantitative detection of HER2-positive cells with a higher contrast compared to HER2-negative cells.


Assuntos
Neoplasias da Mama , Nanopartículas Metálicas , Trastuzumab , Feminino , Humanos , Neoplasias da Mama/diagnóstico , Ouro/química , Nanopartículas Metálicas/química , Peptídeos/química , Trastuzumab/química
5.
MAbs ; 15(1): 2218951, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37300397

RESUMO

Long-term delivery is a successful strategy used to reduce the adverse effects of monoclonal antibody (mAb)-based treatments. Macroporous hydrogels and affinity-based strategies have shown promising results in sustained and localized delivery of the mAbs. Among the potential tools for affinity-based delivery systems, the de novo designed Ecoil and Kcoil peptides are engineered to form a high-affinity, heterodimeric coiled-coil complex under physiological conditions. In this study, we created a set of trastuzumab molecules tagged with various Ecoil peptides and evaluated their manufacturability and characteristics. Our data show that addition of an Ecoil tag at the C-termini of the antibody chains (light chains, heavy chains, or both) does not hinder the production of chimeric trastuzumab in CHO cells or affect antibody binding to its antigen. We also evaluated the influence of the number, length, and position of the Ecoil tags on the capture and release of Ecoil-tagged trastuzumab from macroporous dextran hydrogels functionalized with Kcoil peptide (the Ecoil peptide-binding partner). Notably, our data show that antibodies are released from the macroporous hydrogels in a biphasic manner; the first phase corresponding to the rapid release of residual, unbound trastuzumab from the macropores, followed by the affinity-controlled, slow-rate release of antibodies from the Kcoil-functionalized macropore surface.


Assuntos
Anticorpos Monoclonais , Dextranos , Animais , Cricetinae , Hidrogéis/química , Cricetulus , Peptídeos/química , Trastuzumab/química
6.
J Colloid Interface Sci ; 641: 929-941, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36989819

RESUMO

Polymer-metal nanocomposites have widespread applications in biomedical fields such as imaging, catalysis, and drug delivery. These particles are characterized by combined organic and inorganic properties. Specifically, photothermal nanocomposites incorporating polymeric and plasmonic nanoparticles (NPs) have been designed for both triggered drug release and as imaging agents. However, the usual design of nanocomposites confers characteristic issues, among which are the decrease of optical properties and resulting low photothermal efficiency, as well as interactions with loaded drugs. Herein, we report the design of a core-satellite polymer-metal nanocomposite assembled by coiled-coil peptides and its superior photothermal efficiency compared to electrostatic-driven nanocomposites which is the standard design. We also found that the orientation of gold nanorods on the surface of polymeric NPs is of importance in the final photothermal efficiency and could be exploited for various applications. Our findings provide an alternative to current wrapping and electrostatic assembly of nanocomposites with the help of coiled-coil peptides and an improvement of the control over core-satellite assemblies with plasmonic NPs. It paves the way to highly versatile assemblies due to the nature of coiled-coil peptides to be easily modified and sensitive to pH or temperature.


Assuntos
Nanocompostos , Nanopartículas , Polímeros , Sistemas de Liberação de Medicamentos , Peptídeos/química , Ouro/química , Nanocompostos/química
7.
ACS Appl Bio Mater ; 6(2): 865-873, 2023 02 20.
Artigo em Inglês | MEDLINE | ID: mdl-36625035

RESUMO

Synergistic interactions between 3,4-dihydroxyphenylalanine (Dopa, Y*), cationic residues, and the aromatic rings have been recently highlighted as influential factors that enhance the underwater adhesion strength of mussel foot proteins and their derivatives. In this study, we report the first ever evidence of a cation-catechol-benzene ternary synergy between Y*, lysine (Lys, K), and phenylalanine (Phe, F) in adhesive peptides. We synthesized three hexapeptides containing a different combination of Y*, K, and F, i.e., (KY*)3, (KF)3, and (KY*F)2, respectively, exploring the relationship between the cohesive performance and molecular architecture of peptides. The peptide with the (KY*F)2 sequence displays the strongest underwater cohesion energy of 10.3 ± 0.3 mJ m-2 from direct nanoscale surface force measurements. Combined with molecular dynamics simulation, we demonstrated that there are more bonding interactions (including cation-π, π-π, and hydrogen bond interactions) in (KY*F)2 compared to the other two peptides. In addition, peptide (KY*F)2 still shows the strongest cohesive energies of 7.6 ± 0.7 and 3.7 ± 0.5 mJ m-2 in acidic and high-ionic strength environments, respectively, although the cohesive energy decreases compared to the value in pure water. Our results further explain the underwater cohesion mechanisms combining multiple interactions and offer insights on designing Dopa containing underwater adhesives.


Assuntos
Di-Hidroxifenilalanina , Lisina , Lisina/química , Di-Hidroxifenilalanina/química , Peptídeos/química , Proteínas/química , Adesivos/química , Cátions
8.
J Colloid Interface Sci ; 635: 50-58, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36577355

RESUMO

This study presents novel adhesive materials that use cation-π interactions to achieve highly specific cohesive interaction under water. The materials are short length peptides based on the FKF motif flanked by different side groups. Using the surface forces apparatus, we show that the composition of the side group allows to finely tune the strength of the cohesive and adhesive energies of the peptide and its specificity, meaning its capacity to bind strongly only to substrates bearing the same peptide. The interfacial properties of these adhesive peptides are shown to strongly depend on the composition of the deposition solvent, with DMSO being the solvent of choice to achieve high cohesive and adhesive energies. This result was correlated with the supramolecular structure of the peptide film and confirmed that needle-like structures can significantly enhance the adhesion of the material. Altogether, we showed that cation-π interaction can be used efficiently to create adhesive materials that incorporate features already known for underwater adhesives such as activation via solvent displacement, as well as new ones such as specificity and supramolecular structure enhanced adhesion.


Assuntos
Adesivos , Peptídeos , Peptídeos/química , Adesivos/química , Cátions/química , Solventes
9.
Acta Biomater ; 153: 190-203, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36113720

RESUMO

Macroporous hydrogels possess a vast potential for various applications in the biomedical field. However, due to their large pore size allowing for unrestricted diffusion in the macropore network, macroporous hydrogels alone are not able to efficiently capture and release biomolecules in a controlled manner. There is thus a need for biofunctionalized, affinity-based gels that can efficiently load and release biomolecules in a sustained and controlled manner. For this purpose, we report here the use of a E/K coiled-coil affinity pair for the controlled capture and delivery of growth factors from highly interconnected, macroporous dextran hydrogels. By conjugating the Kcoil peptide to the dextran backbone, we achieved controlled loading and release of Ecoil-tagged Epidermal and Vascular Endothelial Growth Factors. To finely tune the behavior of the gels, we propose four control parameters: (i) macropore size, (ii) Kcoil grafting density, (iii) Ecoil valency and (iv) E/K affinity. We demonstrate that Kcoil grafting can produce a 20-fold increase in passive growth factor capture by macroporous dextran gels. Furthermore, we demonstrate that our gels can release as little as 20% of the loaded growth factors over one week, while retaining bioactivity. Altogether, we propose a versatile, highly tunable platform for the controlled delivery of growth factors in biomedical applications. STATEMENT OF SIGNIFICANCE: This work presents a highly tunable platform for growth factor capture and sustained delivery using affinity peptides in macroporous, fully interconnected dextran hydrogels. It addresses several ongoing challenges by presenting: (i) a versatile platform for the delivery of a wide range of stable, bioactive molecules, (ii) a passive, affinity-based loading of growth factors in the platform, paving the way for in situ (re)loading of the device and (iii) four different control parameters to finely tune growth factor capture and release. Altogether, our macroporous dextran hydrogels have a vast potential for applications in controlled delivery, tissue engineering and regenerative medicine.


Assuntos
Dextranos , Hidrogéis , Hidrogéis/farmacologia , Hidrogéis/química , Dextranos/química , Engenharia Tecidual , Peptídeos e Proteínas de Sinalização Intercelular , Peptídeos
10.
iScience ; 23(5): 101044, 2020 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-32334415

RESUMO

Amyloid are protein aggregates formed by cross ß structures assemblies. Inhibiting amyloid aggregation or facilitating its disassembly are considered to be two major effective therapeutic strategies in diseases involving peptide or protein fibrillation such Alzheimer's disease or diabetes. Using thioflavin-T fluorescence, far-UV circular dichroism spectroscopy, and atomic force microscopy, we found nontoxic and biocompatible black phosphorus quantum dots (BPQDs) appear to have an exceptional capacity to inhibit insulin aggregation and to disassemble formed mature fibrils, even at an ultralow concentration (100 ng/mL). The inhibition of fibrillation persists at all stages of insulin aggregation and increases PC12 cells survival when exposed to amyloid fibrils. Molecular dynamics simulations suggest that BPQDs are able to stabilize the α-helix structure of insulin and obliterate the ß-sheet structure to promote the fibril formation. These characteristics make BPQDs be promising candidate in preventing amyloidosis, disease treatment, as well as in the storage and processing of insulin.

11.
Int J Pharm ; 578: 119078, 2020 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-31988037

RESUMO

Gene therapy is a promising tool for the treatment of various cancers but is hindered by the physico-chemical properties of siRNA and needs a suitable vector for the delivery of siRNA to the target tissue. Bile acid-based block copolymers offers certain advantages for the loading and delivery of siRNA since they can efficiently complex siRNA and bile acids are biocompatible endogenous molecules. In this study, we demonstrate the use of lipids as co-surfactants for the preparation of mixed micelles to improve the siRNA delivery of cholic acid-based block copolymers. Poly(allyl glycidyl ether) (PAGE) and poly(ethylene glycol) (PEG) were polymerized on the surface of cholic acid to afford a star-shaped block copolymer with four arms (CA-PAGE-b-PEG)4. The allyl groups of PAGE were functionalized to bear primary or tertiary amines and folic acid was grafted onto the PEG chain end to increase cell uptake. (CA-PAGE-b-PEG)4 functionalized with either primary or tertiary amines show high siRNA complexation with close to 100% complexation at N/P ratio of 8. Uniform aggregates with diameters between 181 and 188 nm were obtained. DOPE, DSPE-PEG2k, and DSPE-PEG5k lipids were added as co-surfactants to help stabilize the nanoparticles in the cell culture media. Mixed micelles had high siRNA loading with close to 100% functionalization at N/P ratio of 16 and diameters ranging from 153 to 221 nm. The presence of lipids in the mixed micelles improved cell uptake with a concomitant siRNA transfection in HeLa and HeLa-GFP model cells, respectively.


Assuntos
Ácido Cólico/administração & dosagem , Micelas , RNA Interferente Pequeno/administração & dosagem , Ácido Cólico/química , Compostos de Epóxi/administração & dosagem , Compostos de Epóxi/química , Terapia Genética , Proteínas de Fluorescência Verde/genética , Células HeLa , Humanos , Nanopartículas/administração & dosagem , Nanopartículas/química , Fosfatidiletanolaminas/administração & dosagem , Fosfatidiletanolaminas/química , Polietilenoglicóis/administração & dosagem , Polietilenoglicóis/química , RNA Interferente Pequeno/química
12.
Biomacromolecules ; 20(5): 1926-1936, 2019 05 13.
Artigo em Inglês | MEDLINE | ID: mdl-30951296

RESUMO

Affinity-based systems represent a promising solution to control the delivery of therapeutics using hydrogels. Here, we report a hybrid system that is based on the peptidic E/K coiled coil affinity pair to mediate the release of gold nanoparticles (NPs) from alginate scaffolds. On one hand, the gold NPs were functionalized with the Ecoil-tagged epidermal growth factor (EGF). The bioactivity of the grafted EGF and the bioavailability of the Ecoil moiety were confirmed by EGF receptor phosphorylation assays and by capturing the functionalized NPs on a Kcoil-derivatized surface. On the other hand, alginate chains were modified with azido-homoalanine Kcoil (Aha-Kcoil) by azide-alkyne click chemistry. The hybrid system was formed by dispersing NPs functionalized with the Ecoil-tagged EGF in alginate hydrogels containing either 0, 10, or 20% of Kcoil-modified alginate (Alg-Kcoil). With 20% of Alg-Kcoil, the release of Ecoil-functionalized NPs was reduced by half when compared to the release of NPs without Ecoil, whereas little to no differences were noticed with either 0 or 10% of Alg-Kcoil. Differential dynamic microscopy was used to determine the diffusion coefficient of the NPs, and the results showed a decrease in the diffusion coefficient of Ecoil-functionalized NPs, when compared to bare PEGylated NPs. Altogether, our data demonstrated that the E/K coiled coil system can control the release of NPs in a high Kcoil content alginate gel, opening diverse applications in drug delivery.


Assuntos
Alginatos/química , Hidrogéis/química , Nanopartículas Metálicas/química , Linhagem Celular Tumoral , Liberação Controlada de Fármacos , Fator de Crescimento Epidérmico/química , Fator de Crescimento Epidérmico/metabolismo , Receptores ErbB/metabolismo , Ouro/química , Humanos , Ligação Proteica
13.
Mol Pharm ; 16(1): 60-70, 2019 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-30422668

RESUMO

Drugs and proteins with poor intestinal permeability have a limited oral bioavailability. To remediate this problem, a receptor-mediated endocytosis and transcytosis approach was explored. Indeed, the nontoxic ß subunit of cholera toxin (CTB) can cross the intestinal barrier by binding to receptor GM1. In this study, we explored the use of GM1-binding peptides and CTB as potential covalent carriers of poorly permeable molecules. GM1-binding peptides (G23, P3) and CTB were conjugated to poorly permeable fluorescent probes such as fluorescein isothiocyanate (FITC) and albumin-FITC using triethylene glycol spacers and click chemistry. The affinity of the peptide conjugates with receptor GM1 was confirmed by isothermal titration calorimetry or microscale thermophoresis, and the results suggested the involvement of nonspecific interactions. Conjugating the model drugs to G23 and P3 improved the internalization into Caco-2 and T84 cells, although the process was not dependent on the amount of GM1 receptor. However, conjugation of bovine serum albumin FITC to CTB increased the internalization in the same cells in a GM1-dependent pathway. Peptide conjugates demonstrated a limited permeability through a Caco-2 monolayer, whereas G23 and CTB conjugates slightly enhanced permeability through a T84 cell monolayer compared to model drugs alone. Since CTB can improve the permeability of large macromolecules such as albumin, it is an interesting carrier for the improvement of oral bioavailability of various other macromolecules such as heparins, proteins, and siRNAs.


Assuntos
Toxina da Cólera/metabolismo , Mucosa Intestinal/metabolismo , Peptídeos/metabolismo , Animais , Células CACO-2 , Linhagem Celular Tumoral , Citometria de Fluxo , Fluoresceína-5-Isotiocianato/análogos & derivados , Fluoresceína-5-Isotiocianato/química , Humanos , Ligação Proteica , Soroalbumina Bovina/química
14.
Bioconjug Chem ; 29(11): 3866-3876, 2018 11 21.
Artigo em Inglês | MEDLINE | ID: mdl-30350572

RESUMO

Thiol(-click) chemistry has been extensively investigated to conjugate (bio)molecules to polymers. Handling of cysteine-containing molecules may however be cumbersome, especially in the case of fast-oxidizing coiled-coil-forming peptides. In the present study, we investigated the practicality of a one-pot process to concomitantly reduce and conjugate an oxidized peptide to a polymer. Three thiol-based conjugation chemistries (vinyl sulfone (VS), maleimide, and pyridyldithiol) were assayed along with three reducing agents (tris(2-carboxyethyl)phosphine (TCEP), dithiothreitol, and ß-mercaptoethanol). Seven out of the nine possible combinations significantly enhanced the conjugation yield, provided that an adequate concentration of reductant was used. Among them, the coincubation of an oxidized peptide with TCEP and a VS-modified polymer displayed the highest level of conjugation. Our results also provide insights into two topics that currently lack consensus: TCEP is stable in 10 mM phosphate buffered saline and it reacts with thiol-alkylating agents at submillimolar concentrations, and thus should be carefully used in order to avoid interference with thiol-based conjugation reactions.


Assuntos
Química Click/métodos , Peptídeos/química , Polímeros/química , Substâncias Redutoras/química , Compostos de Sulfidrila/química , Alquilação , Maleimidas/síntese química , Maleimidas/química , Oxirredução , Peptídeos/síntese química , Polímeros/síntese química , Substâncias Redutoras/síntese química , Compostos de Sulfidrila/síntese química , Sulfonas/síntese química , Sulfonas/química
15.
Talanta ; 186: 124-132, 2018 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-29784339

RESUMO

A method to explore the stability of two anti-inflammatory peptides in human synovial fluid (HSF) has been developed and validated using liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS). The two peptides are BQ123 Cyclo(-D-Trp-D-Asp-L-Pro-D-Val-L-Leu, Mw = 610.7) and R-954 (AcOrn[Oic2, (αMe)Phe5, DßNal7, Ile8]desArg9-bradykinin, Mw = 1194.4). Human synovial fluid samples were analyzed after a protein precipitation step with acetonitrile and dilution with mobile phase. DMSO was used as anti-adsorptive agent. We used an octyl silane column with formic acid (0.1%, v/v) in water as the aqueous mobile phase and acetonitrile isopropanol-formic acid (20:80, 0.1 v/v) as the organic mobile phase and 0.7 mL/min flow rate. The peptides CY-771 and pepstatin A were used as internal standards. Selective detection was performed by tandem mass spectrometry with a heated electrospray source (HESI), operated in positive ionization mode and in selected reaction monitoring acquisition (SRM). The method limit of quantification (injection volume = 10 µL) was 0.17 ng and 1.2 ng, corresponding to 28 and 102 nmol L-1 for BQ123 and R-954 respectively in human synovial fluid. Calibration curves obtained using matrix-matched calibration standards and internal standard were linear from 20 to 1000 nmol L-1. Precision values (%R.S.D.) were ≤ 14% in the entire linear range. Accuracy measured at a low and a high concentration level ranged from 93.1% to 102%. The recoveries (at 800 nmol L-1) were 96.4% for BQ123 and 102.0% for R-954. The method was successfully applied to follow the degradation kinetics of both peptides in human synovial fluid from arthritic patients during 72 h.


Assuntos
Peptídeos/análise , Líquido Sinovial/química , Cromatografia Líquida , Humanos , Espectrometria de Massas em Tandem
16.
Mol Pharm ; 15(3): 1266-1276, 2018 03 05.
Artigo em Inglês | MEDLINE | ID: mdl-29378128

RESUMO

Doxorubicin (Dox) is a drug of choice in the design of drug delivery systems directed toward breast cancers, but is often limited by loading and control over its release from polymer micelles. Bile acid-based block copolymers present certain advantages over traditional polymer-based systems for drug delivery purposes, since they can enable a higher drug loading via the formation of a reservoir through their aggregation process. In this study, hydrophobic and electrostatic interactions are compared for their influence on Dox loading inside cholic acid based block copolymers. Poly(allyl glycidyl ether) (PAGE) and poly(ethylene glycol) (PEG) were grafted from the cholic acid (CA) core yielding a star-shaped block copolymer with 4 arms (CA-(PAGE- b-PEG)4) and then loaded with Dox via a nanoprecipitation technique. A high Dox loading of 14 wt % was achieved via electrostatic as opposed to hydrophobic interactions with or without oleic acid as a cosurfactant. The electrostatic interactions confer a pH responsiveness to the system. 50% of the loaded Dox was released at pH 5 in comparison to 12% at pH 7.4. The nanoparticles with Dox loaded via hydrophobic interactions did not show such a pH responsiveness. The systems with Dox loaded via electrostatic interactions showed the lowest IC50 and highest cellular internalization, indicating the pre-eminence of this interaction in Dox loading. The blank formulations are biocompatible and did not show cytotoxicity up to 0.17 mg/mL. The new functionalized star block copolymers based on cholic acid show great potential as drug delivery carriers.


Assuntos
Antibióticos Antineoplásicos/administração & dosagem , Doxorrubicina/administração & dosagem , Portadores de Fármacos/química , Composição de Medicamentos/métodos , Antibióticos Antineoplásicos/farmacocinética , Neoplasias da Mama/tratamento farmacológico , Ácido Cólico/química , Doxorrubicina/farmacocinética , Liberação Controlada de Fármacos , Compostos de Epóxi/química , Feminino , Células HeLa , Humanos , Concentração de Íons de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Micelas , Nanopartículas/química , Polietilenoglicóis/química
17.
Biomacromolecules ; 17(1): 88-97, 2016 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-26619081

RESUMO

Using the surface forces apparatus (SFA), interaction forces between supported lipid bilayers were measured in the presence of polyethylene glycol and two other commercially available pegylated triblock polymers, Pluronic F68 and F127. Pluronic F68 has a smaller central hydrophobic block compared to F127 and therefore is more hydrophilic. The study aimed to unravel the effects of polymer architecture and composition on the interactions between the bilayers. Our keys findings show that below the critical aggregation concentration (CAC) of the polymers, a soft, weakly anchored, polymer layer is formed on the surface of the bilayers. The anchoring strength of this physisorbed layer was found to increase significantly with the size of the hydrophobic block of the polymer, and was strongest for the more hydrophobic polymer, F127. Above the CAC, a dense polymer layer, exhibiting gel-like properties, was found to rapidly grow on the bilayers even after mechanical disruption. The cohesive interaction maintaining the gel layer structure was found to be stronger for F127, and was also found to promote the formation of highly structured aggregates on the bilayers.


Assuntos
Bicamadas Lipídicas/química , Polietilenoglicóis/química , Polímeros/química , Interações Hidrofóbicas e Hidrofílicas , Cinética , Fenômenos Mecânicos , Poloxâmero/química , Polietilenos/química , Polipropilenos/química , Propriedades de Superfície
18.
Eur J Pharm Biopharm ; 96: 409-20, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26409200

RESUMO

We developed a nanoparticles (NPs) library from poly(ethylene glycol)-poly lactic acid comb-like polymers with variable amount of PEG. Curcumin was encapsulated in the NPs with a view to develop a delivery platform to treat diseases involving oxidative stress affecting the CNS. We observed a sharp decrease in size between 15 and 20% w/w of PEG which corresponds to a transition from a large solid particle structure to a "micelle-like" or "polymer nano-aggregate" structure. Drug loading, loading efficacy and release kinetics were determined. The diffusion coefficients of curcumin in NPs were determined using a mathematical modeling. The higher diffusion was observed for solid particles compared to "polymer nano-aggregate" particles. NPs did not present any significant toxicity when tested in vitro on a neuronal cell line. Moreover, the ability of NPs carrying curcumin to prevent oxidative stress was evidenced and linked to polymer architecture and NPs organization. Our study showed the intimate relationship between the polymer architecture and the biophysical properties of the resulting NPs and sheds light on new approaches to design efficient NP-based drug carriers.


Assuntos
Antioxidantes/química , Curcumina/química , Lactatos/química , Modelos Químicos , Nanopartículas/química , Neurônios/efeitos dos fármacos , Fármacos Neuroprotetores/química , Polietilenoglicóis/química , Antioxidantes/administração & dosagem , Antioxidantes/efeitos adversos , Antioxidantes/farmacologia , Fenômenos Biofísicos/efeitos dos fármacos , Barreira Hematoencefálica/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Doenças do Sistema Nervoso Central/tratamento farmacológico , Curcumina/administração & dosagem , Curcumina/efeitos adversos , Curcumina/farmacologia , Difusão , Composição de Medicamentos , Sistemas de Liberação de Medicamentos/efeitos adversos , Liberação Controlada de Fármacos , Estabilidade de Medicamentos , Humanos , Lactatos/efeitos adversos , Conformação Molecular , Nanopartículas/efeitos adversos , Nanopartículas/ultraestrutura , Fármacos Neuroprotetores/administração & dosagem , Fármacos Neuroprotetores/efeitos adversos , Fármacos Neuroprotetores/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Tamanho da Partícula , Polietilenoglicóis/efeitos adversos , Propriedades de Superfície
19.
Bioconjug Chem ; 19(10): 2030-9, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18803413

RESUMO

New active particulate polymeric vectors based on branched polyester copolymers of hydroxy-acid and allyl glycidyl ether were developed to target drugs to the inflammatory endothelial cell surface. The hydroxyl and carboxyl derivatives of these polymers allow grafting of ligand molecules on the polyester backbones at different densities. A known potent nonselective selectin ligand was selected and synthesized using a new scheme. This synthesis allowed the grafting of the ligand to the polyester polymers, preserving its binding activity as assessed by docking simulations. Selectin expression on human umbilical cord vascular endothelial cells (HUVEC) was induced with the pro-inflammatory bacterial lipopolysaccharide (LPS) or with the nonselective inhibitor of nitric oxide synthase L-NAME. Strong adhesion of the ligand decorated nanoparticles was evidenced in vitro on activated HUVEC. Binding of nanoparticles bearing ligand molecules could be efficiently inhibited by prior incubation of cells with free ligand, demonstrating that adhesion of the nanoparticles is mediated by specific interaction between the ligand and the selectin receptors. These nanoparticles could be used for specific drug delivery to the activated vascular endothelium, suggesting their application in the treatment of diseases with an inflammatory component such as rheumatoid arthritis and cancer.


Assuntos
Portadores de Fármacos/metabolismo , Células Endoteliais/metabolismo , Selectinas/metabolismo , Animais , Ácidos Carboxílicos/química , Linhagem Celular , Membrana Celular/metabolismo , Portadores de Fármacos/síntese química , Portadores de Fármacos/química , Portadores de Fármacos/toxicidade , Células Endoteliais/citologia , Células Endoteliais/efeitos dos fármacos , Humanos , Ácido Láctico/química , Ligantes , Modelos Moleculares , Nanopartículas/química , Especificidade de Órgãos , Poliésteres , Polímeros/química , Ratos , Especificidade por Substrato , Propriedades de Superfície
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