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1.
Nanomaterials (Basel) ; 10(8)2020 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-32708042

RESUMO

In this work, we exploit the versatile function of cationic phosphonium-conjugated polythiophenes to develop multifunctional platforms for imaging and combined therapy (siRNA delivery and photodynamic therapy). The photophysical properties (absorption, emission and light-induced generation of singlet oxygen) of these cationic polythiophenes were found to be sensitive to molecular weight. Upon light irradiation, low molecular weight cationic polythiophenes were able to light-sensitize surrounding oxygen into reactive oxygen species (ROS) while the highest were not due to its aggregation in aqueous media. These polymers are also fluorescent, allowing one to visualize their intracellular location through confocal microscopy. The most promising polymers were then used as vectors for siRNA delivery. Due to their cationic and amphipathic features, these polymers were found to effectively self-assemble with siRNA targeting the luciferase gene and deliver it in MDA-MB-231 cancer cells expressing luciferase, leading to 30-50% of the gene-silencing effect. In parallel, the photodynamic therapy (PDT) activity of these cationic polymers was restored after siRNA delivery, demonstrating their potential for combined PDT and gene therapy.

2.
Biomater Sci ; 8(13): 3678-3684, 2020 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-32469353

RESUMO

Porphyrin-based periodic mesoporous organosilica nanoparticles (PMO) synthesized from a large functional octatriethoxysilylated porphyrin precursor and allowing two-photon excitation photodynamic therapy (TPE-PDT) and NIR imaging were synthesized. These PMO were grafted with polyethylene glycol (PEG) moieties and an analogue of mannose 6-phosphate functionalized at the anomeric position (AMFA). AMFAs are known to efficiently target mannose 6-phosphate receptors (M6PRs) which are over-expressed in various cancers. Here, we demonstrated for the first time that M6PRs were over-expressed in rhabdomyosarcoma (RMS) cells and could be efficiently targeted with PMO-AMFA allowing TPE imaging and TPE-PDT of RMS cells. The comparison with healthy myoblasts demonstrated an absence of biological effects, suggesting a cancer cell specificity in the biomedical action observed.

3.
J Am Chem Soc ; 142(22): 10184-10197, 2020 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-32368907

RESUMO

In addition to the already described ligand L4a, two pyclen-based lanthanide chelators, L4b and L4c, bearing two specific picolinate two-photon antennas (tailor-made for each targeted metal) and one acetate arm arranged in a dissymmetrical manner, have been synthesized, to form a complete family of lanthanide luminescent bioprobes: [EuL4a], [SmL4a], [YbL4b], [TbL4c], and [DyL4c]. Additionally, the symmetrically arranged regioisomer L4a' was also synthesized as well as its [EuL4a'] complex to highlight the astonishing positive impact of the dissymmetrical N-distribution of the functional chelating arms. The investigation clearly shows the high performance of each bioprobe, which, depending on the complexed lanthanide, could be used in various applications. Each presents high brightness, quantum yields, and lifetimes. Staining of the complexes into living human breast cancer cells was observed. In addition, in vivo two-photon microscopy was performed for the first time on a living zebrafish model with [EuL4a]. No apparent toxicity was detected on the growth of the zebrafish, and images of high quality were obtained.

4.
Inorg Chem ; 59(7): 4567-4575, 2020 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-32149510

RESUMO

We report the postsynthetic functionalization of Prussian blue (PB) nanoparticles by two different luminophores (2-aminoanthracene and rhodamine B). We show that the photoluminescence properties of the fluorophores are modified by a confinement effect upon adsorption and demonstrate that such multifunctional nanosized systems could be used for in vitro imaging.

5.
J Mater Chem B ; 8(7): 1472-1480, 2020 02 19.
Artigo em Inglês | MEDLINE | ID: mdl-31995094

RESUMO

Herein hybrid silica nanoparticles have been engineered to direct the sequential delivery of multiple chemotherapeutic drugs in response to external stimuli such as variations in pH. The nanocarriers consist of conventional MCM-41-type nanoparticles, which have been functionalised with an organic ligand (or stalk) grafted onto the external surface. The stalk is designed to "recognise" a complementary molecule, which serves as a "cap" to block the pores of the nanoparticles. First, camptothecin is introduced into the pores by diffusion prior to capping the pore apertures via molecular recognition. The cap, which is a derivative of 5-fluorouracil, serves as a second cytotoxic drug for synergistic chemotherapy. In vitro tests revealed that negligible release of the drugs occurred at pH 7.4, thus avoiding toxic side effects in the blood stream. In contrast, the stalk/cap complex is destabilised within the endolysosomal compartment (pH 5.5) of cancer cells, where release of the drugs was demonstrated. Furthermore, this environmentally responsive system exhibited a synergistic effect of the two drugs, where the pH-triggered release of the cytotoxic cap followed by diffusion-controlled release of the drug cargo within the pores led to essentially complete elimination of breast cancer cells.

6.
Carbohydr Polym ; 232: 115764, 2020 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-31952581

RESUMO

A new fully biodegradable "reverse" oligosaccharide-based amphiphilic graft copolymer structure with a hydrophobic backbone and hydrophilic side chains, poly(ε-caprolactone)-g-dextran (PCL-g-Dex) was synthetized. For this purpose, "clickable" propargylated PCL (PCL-yne) and azido-dextran (Dex-N3) were prepared to further synthesize PCL-g-Dex copolymer by a Huisgen's cycloaddition. This "reverse" copolymer architecture self-assembled in biodegradable nano-carriers, in the shape of dynamic polymeric micelles, and were loaded with doxorubicin (Dox) anti-cancer drug. Dox-loaded micelles showed different drug releases depending on the pH. Cytotoxicity tests showed that Dox-loaded micelles can selectively kill colon cancer cells (HCT-116) while they have no cytotoxic effect towards healthy cells (CCD-45SK). Fluorescent micelles based on FITC-labelled PCL-g-Dex copolymer were used for fluorescence imaging and flow cytometry assays. These experiments proved the effective and specific internalization of micelles by cancer cells, whereas healthy cells showed a very poor uptake. These results show that PCL-g-Dex micelles may be a promising Dox nano-carrier in cancer chemotherapy.


Assuntos
Antibióticos Antineoplásicos/farmacologia , Dextranos/química , Doxorrubicina/farmacologia , Nanopartículas/química , Poliésteres/química , Antibióticos Antineoplásicos/química , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Doxorrubicina/química , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos , Ensaios de Seleção de Medicamentos Antitumorais , Células HCT116 , Humanos , Micelas , Estrutura Molecular , Tamanho da Partícula , Relação Estrutura-Atividade , Propriedades de Superfície
7.
Molecules ; 24(22)2019 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-31717490

RESUMO

(1) Background: Nanomedicine has recently emerged as a promising field, particularly for cancer theranostics. In this context, nanoparticles designed for imaging and therapeutic applications are of interest. We, therefore, studied the encapsulation of upconverting nanoparticles in mesoporous organosilica nanoparticles. Indeed, mesoporous organosilica nanoparticles have been shown to be very efficient for drug delivery, and upconverting nanoparticles are interesting for near-infrared and X-ray computed tomography imaging, depending on the matrix used. (2) Methods: Two different upconverting-based nanoparticles were synthesized with Yb3+-Er3+ as the upconverting system and NaYF4 or BaLuF5 as the matrix. The encapsulation of these nanoparticles was studied through the sol-gel procedure with bis(triethoxysilyl)ethylene and bis(triethoxysilyl)ethane in the presence of CTAB. (3) Results: with bis(triethoxysilyl)ethylene, BaLuF5: Yb3+-Er3+, nanoparticles were not encapsulated, but anchored on the surface of the obtained mesoporous nanorods BaLuF5: Yb3+-Er3+@Ethylene. With bis(triethoxysilyl)ethane, BaLuF5: Yb3+-Er3+ and NaYF4: Yb3+-Er3+nanoparticles were encapsulated in the mesoporous cubic structure leading to BaLuF5: Yb3+-Er3+@Ethane and NaYF4: Yb3+-Er3+@Ethane, respectively. (4) Conclusions: upconversion nanoparticles were located on the surface of mesoporous nanorods obtained by hydrolysis polycondensation of bis(triethoxysilyl)ethylene, whereas encapsulation occurred with bis(triethoxysilyl)ethane. The later nanoparticles NaYF4: Yb3+-Er3+@Ethane or BaLuF5: Yb3+-Er3+@Ethane were promising for applications with cancer cell imaging or X-ray-computed tomography respectively.


Assuntos
Nanopartículas/química , Compostos de Organossilício/química , Sistemas de Liberação de Medicamentos/métodos , Érbio/química , Etano/química , Fluoretos/química , Hidrólise , Nanomedicina/métodos , Nanotubos/química , Tecnologia Farmacêutica/métodos , Itérbio/química , Ítrio/química
8.
Bioconjug Chem ; 30(10): 2533-2538, 2019 10 16.
Artigo em Inglês | MEDLINE | ID: mdl-31538768

RESUMO

The 300 kDa cation-independent M6P receptor (CI-MPR) mediates ligand internalization and trafficking to the endolysosomal compartments. Because of its endocytotic nature, it has been recognized as a promising class of receptors for target component delivery. Its cellular uptake involves the simultaneous binding of two protein units resulting in the formation of receptor dimers. While many multivalent glycoconjugates have been reported to date, little is known about the topological requests to induce an effective recruitment of CI-MPRs. We herein describe the synthesis and cell uptake ability of a set of highly organized glycoclusters bearing one to three saccharide units. The spatial arrangement of carbohydrate ligands is ensured by a heterocyclic γ-peptide central core.

9.
Chem Commun (Camb) ; 55(81): 12231-12234, 2019 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-31553001

RESUMO

The photophysical properties of a new series of fluorenyl porphyrins bearing water-solubilising oligoethyleneglycol chains are described. These biocompatible compounds present very good two-photon absorption and singlet oxygen generation properties, while retaining some fluorescence in water. After testing in vitro on breast cancer cells, some of them were shown to be efficient non-toxic two-photon photosensitisers allowing for fluorescence imaging, thus demonstrating their theranostic potential.


Assuntos
Fluorenos/química , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/química , Porfirinas/química , Materiais Biocompatíveis/química , Permeabilidade da Membrana Celular , Sobrevivência Celular/efeitos dos fármacos , Humanos , Raios Infravermelhos , Células MCF-7 , Microscopia de Fluorescência por Excitação Multifotônica/métodos , Estrutura Molecular , Imagem Óptica/métodos , Polietilenoglicóis/química , Oxigênio Singlete/química , Relação Estrutura-Atividade
10.
Chem Commun (Camb) ; 55(77): 11619-11622, 2019 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-31501844

RESUMO

Mesoporous organosilica nanoparticles (PHT-PMO) have been prepared from an octa-triethoxysilylated Zn phthalocyanine precursor. These PHT-PMO nanoparticles had no dark toxicity but high phototoxicity when irradiated at 650 nm, and remarkable near-infrared phototoxicity when excited at 760 and 810 nm. The PHT-PMO were then aminated to promote electrostatic complexation with siRNA. Transfection experiments were performed upon NIR irradiation and photochemical internalization was very efficient, leading to 65% luciferase extinction in MCF-7 cancer cells expressing stable luciferase.


Assuntos
Indóis/química , Nanopartículas/química , Compostos Organometálicos/química , Fotoquimioterapia/métodos , RNA Interferente Pequeno/química , Silanos/química , Sobrevivência Celular , Cetrimônio/química , Humanos , Raios Infravermelhos , Luciferases/genética , Células MCF-7 , Processos Fotoquímicos , Porosidade , RNA Interferente Pequeno/metabolismo , Eletricidade Estática , Propriedades de Superfície
11.
Inorg Chem ; 58(18): 12395-12406, 2019 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-31522505

RESUMO

Recently, gold(III) porphyrins have gained great interest as anticancer drugs not only for the stability of gold(III) but also for the functionalization of the porphyrin to allow bridging with another metal such as platinum(II). We report here, for the first time, the synthesis of three new bimetal compounds containing a gold(III) porphyrin conjugated to a platinum diamine moiety through malonate bridging to obtain enhanced cytotoxicity from both metals combined with the phototoxicity of the porphyrin. The three complexes differ in the type of diamine ligand around platinum(II): ammonia (NH3), cyclohexanediamine (CyDA), and pyridylmethylamine (Py). The synthesis was carried out using the complexation of activated malonic acid derivatives with aquadiaminoplatinum(II) complexes, and the products were characterized by IR, NMR, mass spectra, and elementary analysis. The cytotoxic activity of the conjugates was screened in both healthy cell lines and cancer cell lines, human fibroblast cells (FS-68) and human breast cancer cells (MCF-7), and was compared to that of the corresponding platinum(II) complexes. The cyclohexyldiamine (CyDA) derivative exhibited the greatest cytotoxic effect among the series. The results showed that Au(III)/Pt(II) conjugates are more potent by 2-5.6-fold than the corresponding platinum complexes. Moreover, the dyad AuP-PtCyDA is 18% more potent and also more selective toward cancer cells than the parent gold porphyrin substituted with malonic acid. On the other hand, the IC50 of the dyad AuP-PtCyDA is 43% lower than that of AuTPP but is more selective toward healthy cells. Singlet oxygen measurements indicated that gold(III) porphyrin derivatives are poor oxygen sensitizers and cell death occurred potentially due to generation of other reactive oxygen species (ROS) upon reductive quenching of the gold porphyrin excited state. In addition, the increase in cancer cell death obtained after light irradiation is totally absent in healthy cells, demonstrating the specificity of this PDT treatment on cancer cells. Our findings imply that the incorporation of two different cytotoxic metals in the same molecule represents a remarkable cytotoxic effect in comparison to traditional homometallic Pt(II) drugs.

12.
Int J Pharm ; 569: 118585, 2019 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-31376467

RESUMO

In this work, we implemented a supramolecular approach in order to combine photodynamic therapy (PDT) with gene therapy. We made use of a simple cationic guanidylated porphyrin (H2­PG) with the hypothesis that porphyrin aggregates should be capable of complexing siRNA through multivalent interactions and thus contribute to its intracellular delivery, while remaining active photosensitizers for PDT. The PDT effect of H2­PG was shown by incubating human breast cancer cells (MDA-MB-231) with H2­PG followed by light-irradiation at 405 nm. On the other hand, while siRNA do not enter cells alone, we showed, by fluorescence confocal microscopy and flow cytometry, that H2­PG promotes the internalization of Atto-488 siRNA. Finally, studying the combined PDT and delivery of siRNA directed against inhibitory apoptotic protein (IAP) family, we found an additive effect of the two therapies, thereby demonstrating that H2­PG is capable of acting both as a photosensitizer and supramolecular siRNA vector.


Assuntos
Inativação Gênica , Fotoquimioterapia , Fármacos Fotossensibilizantes/administração & dosagem , Porfirinas/administração & dosagem , RNA Interferente Pequeno/administração & dosagem , Linhagem Celular Tumoral , Terapia Genética , Humanos , Proteínas Inibidoras de Apoptose/genética , Fármacos Fotossensibilizantes/química , Porfirinas/química , RNA Interferente Pequeno/química
13.
J Cell Mol Med ; 23(9): 6499-6503, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31293082

RESUMO

In the search of a better enzyme therapy in Pompe disease, the conjugation of mannose 6-phosphonates to the recombinant enzyme appeared as an enhancer of its efficacy. Here, we demonstrated that the increased efficacy of the conjugated enzyme is partly due to a higher intracellular maturation because of its insensitiveness to acid phosphatases during the routing to lysosomes.

14.
Int J Mol Sci ; 20(11)2019 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-31181759

RESUMO

The aim of the present work is the development of highly efficient targeting molecules to specifically address mesoporous silica nanoparticles (MSNs) designed for the photodynamic therapy (PDT) of prostate cancer. We chose the strategy to develop a novel compound that allows the improvement of the targeting of the cation-independent mannose 6-phosphate receptor, which is overexpressed in prostate cancer. This original sugar, a dimannoside-carboxylate (M6C-Man) grafted on the surface of MSN for PDT applications, leads to a higher endocytosis and thus increases the efficacy of MSNs.


Assuntos
Fotoquimioterapia/métodos , Neoplasias da Próstata/metabolismo , Receptor IGF Tipo 2/metabolismo , Linhagem Celular Tumoral , Endocitose , Humanos , Masculino , Manosefosfatos/administração & dosagem , Manosefosfatos/química , Manosefosfatos/farmacologia , Nanopartículas/administração & dosagem , Nanopartículas/química , Nanopartículas/metabolismo , Dióxido de Silício/química
15.
Chemistry ; 25(38): 9026-9034, 2019 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-30972809

RESUMO

Two trispicolinate 1,4,7-triazacyclonane (TACN)-based ligands bearing three picolinate biphotonic antennae were synthetized and their Yb3+ and Gd3+ complexes isolated. One series differs from the other by the absence (L1 )/presence (L2 ) of bromine atoms on the antenna backbone, offering respectively improved optical and singlet-oxygen generation properties. Photophysical properties of the ligands, complexes and micellar Pluronic suspensions were investigated. Complexes exhibit high two-photon absorption cross-section combined either with NIR emission (Yb) or excellent 1 O2 generation (Gd). The very large intersystem crossing efficiency induced by the combination of bromine atom and heavy rare-earth element was corroborated with theoretical calculations. The 1 O2 generation properties of L2 Gd micellar suspension under two-photon activation leads to tumour cell death, suggesting the potential of such structures for theranostic applications.

16.
Molecules ; 24(2)2019 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-30658511

RESUMO

(1) Background: Nanomedicine has recently emerged as a new area of research, particularly to fight cancer. In this field, we were interested in the vectorization of pepstatin A, a peptide which does not cross cell membranes, but which is a potent inhibitor of cathepsin D, an aspartic protease particularly overexpressed in breast cancer. (2) Methods: We studied two kinds of nanoparticles. For pepstatin A delivery, mesoporous silica nanoparticles with large pores (LPMSNs) and hollow organosilica nanoparticles (HOSNPs) obtained through the sol⁻gel procedure were used. The nanoparticles were loaded with pepstatin A, and then the nanoparticles were incubated with cancer cells. (3) Results: LPMSNs were monodisperse with 100 nm diameter. HOSNPs were more polydisperse with diameters below 100 nm. Good loading capacities were obtained for both types of nanoparticles. The nanoparticles were endocytosed in cancer cells, and HOSNPs led to the best results for cancer cell killing. (4) Conclusions: Mesoporous silica-based nanoparticles with large pores or cavities are promising for nanomedicine applications with peptides.


Assuntos
Neoplasias da Mama/metabolismo , Sistemas de Liberação de Medicamentos , Nanopartículas/química , Pepstatinas/administração & dosagem , Dióxido de Silício/química , Linhagem Celular Tumoral , Feminino , Humanos , Nanopartículas/ultraestrutura , Pepstatinas/química , Porosidade
17.
Chemistry ; 25(14): 3637-3649, 2019 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-30620107

RESUMO

The synthesis and the photophysical properties of a new class of fully organic monodisperse nanoparticles for combined two-photon imaging and photodynamic therapy are described. The design of such nanoparticles is based on the covalent immobilization of a dedicated quadrupolar dye that combines excellent two-photon absorbing (2PA) properties, fluorescence and singlet oxygen generation ability, in a phosphorous-based dendrimeric architecture. First, a bifunctional quadrupolar dye bearing two different grafting moieties, a phenol function and an aldehyde function, was synthesized. It was then covalently grafted through its phenol function to a phosphorus-based dendrimer scaffold of generation 1. The remaining aldehyde functions were then used to continue the dendrimer synthesis up to generation 2, introducing finally 24 water-solubilizing triethyleneglycol chains at its periphery. A dendrimer confining 12 photoactive quadrupolar units in its inner scaffold and showing water solubility was thus obtained. Interestingly, the G1 and G2 dendrimers retain some fluorescence as well as significant singlet oxygen production efficiencies while they were found to show very high 2PA cross-sections in a broad range of the NIR biological spectral window. Hydrophilic dendrimer G2 was tested in vitro on breast cancer cells, first in one- and two-photon microscopy, which allowed for visualization of their cell internalization, then in two-photon photodynamic therapy. While being nontoxic in the dark and, more importantly, under exposure to daylight, dendrimer G2 proved to be a very efficient cell-death inducer only under two-photon irradiation in the NIR.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/tratamento farmacológico , Dendrímeros/farmacologia , Corantes Fluorescentes/farmacologia , Nanopartículas/química , Fármacos Fotossensibilizantes/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Dendrímeros/química , Feminino , Corantes Fluorescentes/química , Humanos , Interações Hidrofóbicas e Hidrofílicas , Células MCF-7 , Imagem Óptica/métodos , Fotoquimioterapia/métodos , Fótons , Fármacos Fotossensibilizantes/química , Nanomedicina Teranóstica/métodos
18.
Cancer Rep (Hoboken) ; 2(5): e1186, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32721109

RESUMO

BACKGROUND: Bridged silsesquioxane nanoparticles (BSNs) recently described represent a new class of nanoparticles exhibiting versatile applications and particularly a strong potential for nanomedicine. AIMS: In this work, we describe the synthesis of BSNs from an octasilylated functional porphyrin precursor (PORBSNs) efficiently obtained through a click reaction. These innovative and very small-sized nanoparticles were functionalized with PEG and mannose (PORBSNs-mannose) in order to target breast tumors in vivo. METHODS AND RESULTS: The structure of these nanoparticles is constituted of porphyrins J aggregates that allow two-photon spatiotemporal excitation of the nanoparticles. The therapeutic potential of such photoactivable nanoparticles was first studied in vitro, in human breast cancer cells in culture and then in vivo on zebrafish embryos bearing human tumors. These animal models were intravenously injected with 5 nL of a solution containing PORBSNs-mannose. An hour and half after the injection of photoactivable and targeted nanoparticles, the tumor areas were excited for few seconds with a two-photon beam induced focused laser. We observed strong tumor size decrease, with the involvement of apoptosis pathway activation. CONCLUSION: We demonstrated the high targeting, imaging, and therapeutic potential of PORBSNs-mannose injected in the blood stream of zebrafish xenografted with human tumors.

20.
Chemistry ; 24(44): 11426-11432, 2018 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-29846978

RESUMO

Sugars play key roles in many molecular and cellular communication processes involving a family of proteins named lectins. The low affinity associated with sugar recognition is generally counterbalanced by the multivalent nature of the interaction. While many polyglycosylated architectures have been described, only a few studies focused on the impact of topology variations of the multivalent structures on the interaction with lectin proteins. One major interest of our group concerns the design of new highly predictable and stable molecular pseudo-peptide architectures for therapeutic applications. In such a context, we described a class of constrained heterocyclic γ-amino acids built around a thiazole ring, named ATCs. ATC oligomers are helical molecules resulting from the formation of a highly stable C9 hydrogen-bonding pattern. Following our program, we herein address the potential of ATC oligomers as tunable scaffolds for the development of original multivalent glycoclusters.

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