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1.
Cell Death Dis ; 15(6): 419, 2024 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-38879621

RESUMEN

TRPV6 calcium channel is a prospective target in prostate cancer (PCa) since it is not expressed in healthy prostate while its expression increases during cancer progression. Despite the role of TRPV6 in PCa cell survival and apoptotic resistance has been already established, no reliable tool to target TRPV6 channel in vivo and thus to reduce tumor burden is known to date. Here we report the generation of mouse monoclonal antibody mAb82 raised against extracellular epitope of the pore region of the channel. mAb82 inhibited TRPV6 currents by 90% at 24 µg/ml in a dose-dependent manner while decreasing store-operated calcium entry to 56% at only 2.4 µg/ml. mAb82 decreased PCa survival rate in vitro by 71% at 12 µg/ml via inducing cell death through the apoptosis cascade via activation of the protease calpain, following bax activation, mitochondria enlargement, and loss of cristae, Cyt C release, pro-caspase 9 cleavage with the subsequent activation of caspases 3/7. In vivo, mice bearing either PC3Mtrpv6+/+ or PC3Mtrpv6-/-+pTRPV6 tumors were successfully treated with mAb82 at the dose as low as 100 µg/kg resulting in a significant reduction tumor growth by 31% and 90%, respectively. The survival rate was markedly improved by 3.5 times in mice treated with mAb82 in PC3Mtrpv6+/+ tumor group and completely restored in PC3Mtrpv6-/-+pTRPV6 tumor group. mAb82 showed a TRPV6-expression dependent organ distribution and virtually no toxicity in the same way as mAbAU1, a control antibody of the same Ig2a isotype. Overall, our data demonstrate for the first time the use of an anti-TRPV6 monoclonal antibody in vitro and in vivo in the treatment of the TRPV6-expressing PCa tumors.


Asunto(s)
Anticuerpos Monoclonales , Apoptosis , Canales de Calcio , Neoplasias de la Próstata , Canales Catiónicos TRPV , Masculino , Canales Catiónicos TRPV/metabolismo , Neoplasias de la Próstata/patología , Neoplasias de la Próstata/tratamiento farmacológico , Neoplasias de la Próstata/metabolismo , Apoptosis/efectos de los fármacos , Humanos , Animales , Anticuerpos Monoclonales/farmacología , Anticuerpos Monoclonales/uso terapéutico , Ratones , Canales de Calcio/metabolismo , Línea Celular Tumoral , Ensayos Antitumor por Modelo de Xenoinjerto , Calpaína/metabolismo , Calcio/metabolismo
2.
ACS Appl Mater Interfaces ; 15(31): 37327-37336, 2023 Aug 09.
Artículo en Inglés | MEDLINE | ID: mdl-37505220

RESUMEN

Solar-driven interfacial evaporation is an eco-friendly solution for tackling the impending water scarcity the world is facing in our century. In this work, a solar-driven interfacial evaporator was prepared from cigarette butts loaded with petroleum coke powder (Filter-PetCoke), a by-product of the oil refinery processes, for the improvement of the absorption of the incident solar light. A comparison between a flat 2D and a 3D evaporator with a surface composed of orderly patterned protrusions of 2.1 cm was carried out to assess the influence of the evaporator configuration on the evaporation performance. The 3D evaporator (3D Filter-PetCoke) achieved by far the best performance (evaporation rate: 1.97 ± 0.08 kg m-2 h-1 and solar conversion efficiency: 93.2 ± 5.4%) among the prepared samples (3D Filter-PetCoke, 3D Filter, 2D Filter-PetCoke, and 2D Filter). In addition, this configuration seems to be adaptable for real and more massive operation because of the geometry of the evaporator. The high efficiency was ascribed to the good heat generation of the petroleum coke and the excellent heat management of the 3D structure of the evaporator. Moreover, this evaporator was resistant to multiple repeated usages without significant efficiency loss and capable of producing drinking water from seawater and Escherichia coli (E. coli)-contaminated water. The findings in this work indicate that this evaporator is pertinent to real situations to supply safe freshwater very efficiently from chemically/biologically contaminated water.

3.
Cells ; 12(6)2023 03 20.
Artículo en Inglés | MEDLINE | ID: mdl-36980281

RESUMEN

Improvement of insulin secretion by pancreatic ß-cells and preservation of their mass are the current challenges that future antidiabetic drugs should meet for achieving efficient and long-term glycemic control in patients with type 2 diabetes (T2D). The successful development of glucagon-like peptide 1 (GLP-1) analogues, derived from the saliva of a lizard from the Helodermatidae family, has provided the proof of concept that antidiabetic drugs directly targeting pancreatic ß-cells can emerge from venomous animals. The literature reporting on the antidiabetic effects of medicinal plants suggests that they contain some promising active substances such as polyphenols and alkaloids, which could be active as insulin secretagogues and ß-cell protectors. In this review, we discuss the potential of several polyphenols, alkaloids and venom peptides from snake, frogs, scorpions and cone snails. These molecules could contribute to the development of new efficient antidiabetic medicines targeting ß-cells, which would tackle the progression of the disease.


Asunto(s)
Alcaloides , Diabetes Mellitus Tipo 2 , Animales , Hipoglucemiantes/farmacología , Hipoglucemiantes/uso terapéutico , Hipoglucemiantes/química , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Polifenoles/farmacología , Polifenoles/uso terapéutico , Ponzoñas/farmacología , Ponzoñas/uso terapéutico , Péptidos/farmacología , Alcaloides/farmacología , Alcaloides/uso terapéutico
4.
Nanoscale ; 14(39): 14683-14694, 2022 Oct 13.
Artículo en Inglés | MEDLINE | ID: mdl-36165351

RESUMEN

Pancreatic islet amyloid deposition is a pathological hallmark of Type 2 diabetes (T2D), contributing to reduced functional ß-cell mass. Islet amyloids result not only from the aggregation and fibrillation of human islet amyloid polypeptide (hIAPP), but also from beta-amyloid 42 (Aß42), the key amyloidogenic peptide linked to Alzheimer's disease. Importantly, Aß42 and hIAPP aggregates (IAPP:Aß42) can interact with each other and form some harmful heterocomplex fibrils. While it is well-documented that hIAPP aggregation occurs only when islets are exposed to a diabetic environment, including hyperglycemia and/or elevated concentrations of saturated fatty acids (SFAs), it remains unclear if hIAPP and IAPP:Aß42 heteromer fibrillations are directly or indirectly triggered by this environment. In this study, we show the interplay between high glucose concentrations and palmitate as the SFA in the aggregation of hIAPP. In addition, we outline that the interaction of hIAPP and Aß42 leads to the formation of complex protein aggregates, which are toxic to ß-cells. Carbon nanocolloids in the form of positively charged carbon quantum dots (CQD-pos) efficiently prevent single amyloid aggregation and the formation of IAPP:Aß42 heterocomplexes. We provide clear evidence with this study that the diabetogenic environment of islets could directly contribute to the formation of homomeric and heteromeric amyloid aggregates and fibrils in T2D. We also propose carbon nanocolloids as biocompatible nanomaterials for developing innovative therapeutic strategies that prevent the decline of functional ß-cell mass.


Asunto(s)
Diabetes Mellitus Tipo 2 , Puntos Cuánticos , Amiloide/química , Péptidos beta-Amiloides/metabolismo , Proteínas Amiloidogénicas , Carbono , Diabetes Mellitus Tipo 2/metabolismo , Ácidos Grasos , Glucosa , Humanos , Polipéptido Amiloide de los Islotes Pancreáticos/química , Palmitatos , Agregado de Proteínas , Puntos Cuánticos/toxicidad
5.
Int J Mol Sci ; 23(12)2022 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-35743115

RESUMEN

In the fight against prostate cancer (PCa), TRPM8 is one of the most promising clinical targets. Indeed, several studies have highlighted that TRPM8 involvement is key in PCa progression because of its impact on cell proliferation, viability, and migration. However, data from the literature are somewhat contradictory regarding the precise role of TRPM8 in prostatic carcinogenesis and are mostly based on in vitro studies. The purpose of this study was to clarify the role played by TRPM8 in PCa progression. We used a prostate orthotopic xenograft mouse model to show that TRPM8 overexpression dramatically limited tumor growth and metastasis dissemination in vivo. Mechanistically, our in vitro data revealed that TRPM8 inhibited tumor growth by affecting the cell proliferation and clonogenic properties of PCa cells. Moreover, TRPM8 impacted metastatic dissemination mainly by impairing cytoskeleton dynamics and focal adhesion formation through the inhibition of the Cdc42, Rac1, ERK, and FAK pathways. Lastly, we proved the in vivo efficiency of a new tool based on lipid nanocapsules containing WS12 in limiting the TRPM8-positive cells' dissemination at metastatic sites. Our work strongly supports the protective role of TRPM8 on PCa progression, providing new insights into the potential application of TRPM8 as a therapeutic target in PCa treatment.


Asunto(s)
Neoplasias de la Próstata , Canales Catiónicos TRPM , Animales , Carcinogénesis/metabolismo , Línea Celular Tumoral , Movimiento Celular , Proliferación Celular , Humanos , Masculino , Proteínas de la Membrana/metabolismo , Ratones , Metástasis de la Neoplasia/patología , Próstata/patología , Neoplasias de la Próstata/metabolismo , Canales Catiónicos TRPM/genética , Canales Catiónicos TRPM/metabolismo
6.
Nanomaterials (Basel) ; 11(9)2021 Aug 24.
Artículo en Inglés | MEDLINE | ID: mdl-34578471

RESUMEN

The synthesis of multifunctional photothermal nanoagents for antibiotic loading and release remains a challenging task in nanomedicine. Herein, we investigated a simple, low-cost strategy for the preparation of CuS-BSA nanoparticles (NPs) loaded with a natural enzyme, lysozyme, as an antibacterial drug model under physiological conditions. The successful development of CuS-BSA NPs was confirmed by various characterization tools such as transmission electron microscopy (TEM), X-ray diffraction (XRD), Raman spectroscopy, and X-ray photoelectron spectroscopy (XPS). Lysozyme loading onto CuS-BSA NPs was evaluated by UV/vis absorption spectroscopy, Fourier-transform infrared spectroscopy (FTIR), zeta potential, and dynamic light scattering measurements. The CuS-BSA/lysozyme nanocomposite was investigated as an effective means for bacterial elimination of B. subtilis (Gram-positive) and E. coli (Gram-negative), owing to the combined photothermal heating performance of CuS-BSA and lysozyme release under 980 nm (0.7 W cm-2) illumination, which enhances the antibiotic action of the enzyme. Besides the photothermal properties, CuS-BSA/lysozyme nanocomposite possesses photodynamic activity induced by NIR illumination, which further improves its bacterial killing efficiency. The biocompatibility of CuS-BSA and CuS-BSA/Lysozyme was elicited in vitro on HeLa and U-87 MG cancer cell lines, and immortalized human hepatocyte (IHH) cell line. Considering these advantages, CuS-BSA NPs can be used as a suitable drug carrier and hold promise to overcome the limitations of traditional antibiotic therapy.

7.
Cells ; 9(3)2020 03 23.
Artículo en Inglés | MEDLINE | ID: mdl-32209981

RESUMEN

BACKGROUND: The main goals of cancer treatment are not only to eradicate the tumor itself but also to elicit a specific immune response that overcomes the resistance of tumor cells against chemo- and radiotherapies. Hyperthermia was demonstrated to chemo- and radio-sensitize cancerous cells. Many reports have confirmed the immunostimulatory effect of such multi-modal routines. METHODS: We evaluated the interaction of graphene oxide (GO) nanosheets; its derivatives reduced GO and PEGylated rGO, with components of peripheral blood and evaluated its thermal conductivity to induce cell death by localized hyperthermia. RESULTS: We confirmed the sterility and biocompatibility of the graphene nanomaterials and demonstrated that hyperthermia applied alone or in the combination with radiotherapy induced much more cell death in tumor cells than irradiation alone. Cell death was confirmed by the release of lactate dehydrogenase from dead and dying tumor cells. CONCLUSION: Biocompatible GO and its derivatives can be successfully used in graphene-induced hyperthermia to elicit tumor cell death.


Asunto(s)
Materiales Biocompatibles/química , Fenómenos Químicos , Grafito/química , Hipertermia Inducida , Nanopartículas/química , Neoplasias/patología , Muerte Celular , Supervivencia Celular , Humanos , Leucocitos/metabolismo , Ensayo de Materiales , Melanoma Experimental/patología , Nanopartículas/ultraestructura , Activación Plaquetaria
8.
ACS Appl Mater Interfaces ; 11(46): 42964-42974, 2019 Nov 20.
Artículo en Inglés | MEDLINE | ID: mdl-31633330

RESUMEN

Therapeutic options for the highly pathogenic human coronavirus (HCoV) infections are urgently needed. Anticoronavirus therapy is however challenging, as coronaviruses are biologically diverse and rapidly mutating. In this work, the antiviral activity of seven different carbon quantum dots (CQDs) for the treatment of human coronavirus HCoV-229E infections was investigated. The first generation of antiviral CQDs was derived from hydrothermal carbonization of ethylenediamine/citric acid as carbon precursors and postmodified with boronic acid ligands. These nanostructures showed a concentration-dependent virus inactivation with an estimated EC50 of 52 ± 8 µg mL-1. CQDs derived from 4-aminophenylboronic acid without any further modification resulted in the second-generation of anti-HCoV nanomaterials with an EC50 lowered to 5.2 ± 0.7 µg mL-1. The underlying mechanism of action of these CQDs was revealed to be inhibition of HCoV-229E entry that could be due to interaction of the functional groups of the CQDs with HCoV-229E entry receptors; surprisingly, an equally large inhibition activity was observed at the viral replication step.


Asunto(s)
Antivirales , Carbono , Coronavirus Humano 229E/fisiología , Infecciones por Coronavirus , Puntos Cuánticos , Replicación Viral/efectos de los fármacos , Antivirales/farmacología , Carbono/química , Carbono/farmacología , Línea Celular Tumoral , Infecciones por Coronavirus/tratamiento farmacológico , Infecciones por Coronavirus/metabolismo , Infecciones por Coronavirus/patología , Humanos , Puntos Cuánticos/química , Puntos Cuánticos/uso terapéutico
9.
Photochem Photobiol Sci ; 17(11): 1651-1674, 2018 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-30022180

RESUMEN

In this review, the use of mesoporous silica nanoparticles for photodynamic therapy (PDT) applications is described for the year 2017. Since the pioneering work in 2009, nanosystems involving mesoporous silica nanoparticles have gained in complexity with a sophisticated core-shell system able to perform multi-imaging and multi-therapies, not only for cancer diseases but also for anti-microbial therapy, atherosclerosis, or Alzheimer disease. Near-infrared, excitation light based on up-converting systems, X-rays or persistent luminescent systems are described for deeper tissue treatments.


Asunto(s)
Nanopartículas/química , Neoplasias/tratamiento farmacológico , Fotoquimioterapia , Fármacos Fotosensibilizantes/farmacología , Dióxido de Silicio/farmacología , Enfermedad de Alzheimer/tratamiento farmacológico , Aterosclerosis/tratamiento farmacológico , Bacterias/efectos de los fármacos , Tamaño de la Partícula , Fármacos Fotosensibilizantes/química , Porosidad , Dióxido de Silicio/química , Propiedades de Superficie
10.
Colloids Surf B Biointerfaces ; 170: 347-354, 2018 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-29940501

RESUMEN

In the last years, carbon-based nanomaterials have attracted considerable attention in a wide range of fields, particularly in biomedicine, owing to their remarkable photo-physical and chemical properties. In this study, we demonstrate that amine-terminated carbon dots (CDs-NH2) functionalized with ampicillin (AMP) offer a new perspective for antibacterial treatment. The amine-functionalized carbon dots were used as a carrier for immobilization and delivery of ampicillin (CDs-AMP) and as a visible light-triggered antibacterial material. Additionally, AMP immobilization on the CDs-NH2 surface improves its stability in solution as compared to free AMP. The AMP conjugated CDs platform combines the antibacterial function of AMP and conserves the intrinsic theranostic properties of CDs-NH2. Therefore, the AMP immobilized onto CDs-NH2 surface together with the generation of moderate quantities of reactive oxygen species under visible light illumination are very effective to inactivate the growth of Escherichia coli.


Asunto(s)
Aminas/farmacología , Ampicilina/farmacología , Antibacterianos/farmacología , Carbono/farmacología , Escherichia coli K12/efectos de los fármacos , Luz , Puntos Cuánticos/química , Adulto , Aminas/síntesis química , Aminas/química , Ampicilina/química , Antibacterianos/síntesis química , Antibacterianos/química , Carbono/química , Muerte Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Escherichia coli K12/citología , Femenino , Células HeLa , Humanos , Pruebas de Sensibilidad Microbiana , Fotoquimioterapia , Relación Estructura-Actividad , Células Tumorales Cultivadas
11.
J Mater Chem B ; 6(37): 5949-5963, 2018 Oct 07.
Artículo en Inglés | MEDLINE | ID: mdl-32254715

RESUMEN

Photodynamic therapy (PDT) has developed into a new clinical and non-invasive treatment for cancer over the past 30 years. By the combination of three non-toxic partners, i.e. a photosensitizer (PS), molecular oxygen (O2) and light, cytotoxic reactive oxygen species (ROS) are locally produced leading to irreversible vascular and cellular damage. In the present study, we report for the first time that the combination of two photosensitizers (2 PSs: Protoporphyrin IX, PpIX and Hypericin, Hy) loaded in the same lipid nanocapsules (LNCs) leads to enhanced photodynamic therapy efficiency when compared with previously reported systems. The 2 PS-loaded LNCs are shown to increase the in vitro phototoxicity at the nanomolar range (IC50 = 274 and 278 nM on HeLa and MDA-MB-231 cell lines, respectively), whereas the corresponding single PS-loaded LNCs at the same concentration exhibit a phototoxicity two times lower. Intracellular localization in HeLa cells indicates a subcellular asymmetry of PpIX and Hy, in the plasma, ER membranes and round internal structures. The biodistribution of LNCs was studied upon different routes of injection into Swiss nude mice; based on the obtained data, LNCs were injected intratumorally and used to slow the growth of xenograft tumors in mice. The results obtained in this study suggest that the combination of two or more PSs may be a promising strategy to improve the efficacy of conventional photodynamic therapy as well as to reduce dark toxicity.

12.
ACS Appl Mater Interfaces ; 9(39): 34194-34203, 2017 Oct 04.
Artículo en Inglés | MEDLINE | ID: mdl-28905618

RESUMEN

Materials based on reduced graphene oxide (rGO) have shown to be amenable to noncovalent functionalization through hydrophobic interactions. The scaffold, however, does not provide sufficient covalent linkage given the low number of reactive carboxyl and alcohol groups typically available on the rGO. The integration of clickable groups, particularly the ones that can undergo efficient conjugation without any metal catalyst, would allow facile functionalization of these materials. This study reports on the noncovalent association of a maleimide-containing catechol (dopa-MAL) surface anchor onto the rGO. Thiol-maleimide chemistry allows thereafter the facile attachment of thiol-containing molecules under ambient metal-free conditions. Although the attachment of glutathione and 6-(ferrocenyl)hexanethiol was used as model thiols, the attachment of a cancer cell targeting cyclic peptide, c(RGDfC), opened the possibility of using the dopa-MAL-modified rGO as a targeted drug delivery system for doxorubicin (DOX). Although free DOX showed to be more effective at killing the human cervical cancer cells (HeLa) over human breast adenocarcinoma cancer cells (MDA-MB-231), the DOX-loaded rGO/dopa-MAL-c (RGDfC) nanostructure showed an opposite effect being notably more effective at targeting and killing the MDA-MB-231 cells. The effect is enhanced upon laser irradiation for 10 min at 2 W cm-2. The facile fabrication and functionalization to readily obtain a functional material in a modular fashion make this clickable-rGO construct an attractive platform for various applications.


Asunto(s)
Grafito/química , Sistemas de Liberación de Medicamentos , Humanos , Maleimidas , Compuestos de Sulfhidrilo
13.
J Mater Chem B ; 5(32): 6557-6565, 2017 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-32264417

RESUMEN

Despite the advantages of an electrochemical control for drug release, only a handful of electrochemical-based release systems have been developed so far. We report herein on the development of an electrochemically activatable platform for on-demand delivery of drugs. It is based on flexible gold thin film electrodes coated with porous reduced graphene oxide (prGO) nanosheets onto which the drug of interest has been integrated beforehand. Two different drugs are investigated here: ondansetron hydrochloride (ODS), a selective 5-HT3 receptor antagonist used for preventing nausea and vomiting caused by chemotherapy and radiotherapy, and ampicillin (AMP), an antibiotic to prevent and treat a number of bacterial infections such as respiratory tract infections, urinary tract infections, and meningitis. In the case of ODS, application of a negative potential bias of -0.8 V results in a sustained slow ODS release with an ODS flux of 47 µg cm-2 h-1. In the case of AMP, we show that polyethyleneimine modified prGO (prGO/PEI) is an extremely efficient matrix. Upon the application of +0.8 V, 24% of AMP could be released from the electrical interface in a time span of 2 h. The released AMP kept its antibacterial activity as demonstrated by antimicrobial tests. These examples illustrate the major benefits of the developed approach for biomedical applications.

14.
Molecules ; 20(8): 14051-81, 2015 Aug 03.
Artículo en Inglés | MEDLINE | ID: mdl-26247927

RESUMEN

Multivalent interactions are omnipresent in biology and confer biological systems with dramatically enhanced affinities towards different receptors. Such multivalent binding interactions have lately been considered for the development of new therapeutic strategies against bacterial and viral infections. Multivalent polymers, dendrimers, and liposomes have successfully targeted pathogenic interactions. While a high synthetic effort was often needed for the development of such therapeutics, the integration of multiple ligands onto nanostructures turned to be a viable alternative. Particles modified with multiple ligands have the additional advantage of creating a high local concentration of binding molecules. This review article will summarize the different nanoparticle-based approaches currently available for the treatment of viral infections.


Asunto(s)
Nanoestructuras/uso terapéutico , Virosis/tratamiento farmacológico , Portadores de Fármacos , Modelos Biológicos , Proteínas del Envoltorio Viral/química , Replicación Viral
15.
Nanoscale ; 7(6): 2325-35, 2015 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-25559389

RESUMEN

Recent advances in nanotechnology have seen the development of a number of microbiocidal and/or anti-adhesive nanoparticles displaying activity against biofilms. In this work, trimeric thiomannoside clusters conjugated to nanodiamond particles (ND) were targeted for investigation. NDs have attracted attention as a biocompatible nanomaterial and we were curious to see whether the high mannose glycotope density obtained upon grouping monosaccharide units in triads might lead to the corresponding ND-conjugates behaving as effective inhibitors of E. coli type 1 fimbriae-mediated adhesion as well as of biofilm formation. The required trimeric thiosugar clusters were obtained through a convenient thiol-ene "click" strategy and were subsequently conjugated to alkynyl-functionalized NDs using a Cu(I)-catalysed "click" reaction. We demonstrated that the tri-thiomannoside cluster-conjugated NDs (ND-Man3) show potent inhibition of type 1 fimbriae-mediated E. coli adhesion to yeast and T24 bladder cells as well as of biofilm formation. The biofilm disrupting effects demonstrated here have only rarely been reported in the past for analogues featuring such simple glycosidic motifs. Moreover, the finding that the tri-thiomannoside cluster (Man3N3) is itself a relatively efficient inhibitor, even when not conjugated to any ND edifice, suggests that alternative mono- or multivalent sugar-derived analogues might also be usefully explored for E. coli-mediated biofilm disrupting properties.


Asunto(s)
Biopelículas , Diamante/química , Escherichia coli/metabolismo , Fimbrias Bacterianas/metabolismo , Manósidos/química , Nanopartículas/química , Adhesión Bacteriana , Materiales Biocompatibles/química , Carbohidratos/química , Línea Celular Tumoral , Cromatografía en Capa Delgada , Dimerización , Glicósidos/química , Proteínas Fluorescentes Verdes/metabolismo , Humanos , Espectroscopía de Resonancia Magnética , Nanoconjugados , Nanotecnología , Tamaño de la Partícula , Espectroscopía de Fotoelectrones , Solventes/química
16.
Nanoscale ; 7(4): 1392-402, 2015 Jan 28.
Artículo en Inglés | MEDLINE | ID: mdl-25502878

RESUMEN

The search for viral entry inhibitors that selectively target viral envelope glycoproteins has attracted increasing interest in recent years. Amongst the handful of molecules reported to show activity as hepatitis C virus (HCV) entry inhibitors are a variety of glycan-binding proteins including the lectins, cyanovirin-N (CV-N) and griffithsin. We recently demonstrated that boronic acid-modified nanoparticles are able to reduce HCV entry through a similar mechanism to that of lectins. A major obstacle to any further development of these nanostructures as viral entry inhibitors is their only moderate maximal inhibition potential. In the present study, we report that lipid nanocapsules (LNCs), surface-functionalized with amphiphilic boronic acid (BA) through their post-insertion into the semi-rigid shell of the LNCs, are indeed far superior as HCV entry inhibitors when compared with previously reported nanostructures. These 2(nd) generation particles (BA-LNCs) are shown to prevent HCV infection in the micromolar range (IC50 = 5.4 µM of BA moieties), whereas the corresponding BA monomers show no significant effects even at the highest analyzed concentration (20 µM). The new BA-LNCs are the most promising boronolectin-based HCV entry inhibitors reported to date and are thus observed to show great promise in the development of a pseudolectin-based therapeutic agent.


Asunto(s)
Ácidos Borónicos/química , Hepacivirus/fisiología , Nanocápsulas/química , Anticuerpos/inmunología , Carbocianinas/química , Línea Celular , Supervivencia Celular/efectos de los fármacos , Humanos , Microscopía Fluorescente , Nanocápsulas/toxicidad , Tamaño de la Partícula , Polietilenglicoles/química , Triglicéridos/química , Proteínas del Envoltorio Viral/inmunología , Proteínas del Envoltorio Viral/metabolismo , Internalización del Virus/efectos de los fármacos
17.
Nanoscale ; 6(13): 7379-90, 2014 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-24871584

RESUMEN

The paper reports on the preparation of lipid nanocapsules (LNCs) functionalized with poly(ethyleneimine) (PEI) moieties and their successful use as drug and gene delivery systems. The cationic LNCs were produced by a phase inversion process with a nominal size of 25 nm and subsequently modified with PEI chains using a transacylation reaction. The functionalization process allowed good control over the nanoscale particle size (26.2 ± 3.9 nm) with monodisperse size characteristics (PI < 0.2) and positive surface charge up to +18.7 mV. The PEI-modified LNCs (LNC25-T) displayed good buffering capacity. Moreover, the cationic LNC25-T were able to condense DNA and form complexes via electrostatic interactions in a typical weight ratio-dependent relationship. It was found that the mean diameter of LNC25-T/pDNA complexes increased to ∼40-50 nm with the LNC25-T/pDNA ratio from 1 to 500. Gel electrophoresis and cell viability experiments showed that the LNC25-T/pDNA complexes had high stability with no cytotoxicity due to the anchored PEI polymers on the surface of LNCs. Finally, the transfection efficiency of the LNC25-T/pDNA complexes was studied and evaluated on HEK cell lines in comparison with free PEI/pDNA polyplexes. The combination of cationic LNCs with pDNA exhibited more than a 2.8-fold increase in transfection efficiency compared to the standard free PEI/pDNA polyplexes at the same PEI concentrations. Moreover, we have demonstrated that LNC25-T/pDNA loaded with a hydrophobic drug, paclitaxel, showed high drug efficacy. The high transfection efficiency combined with the potential of simultaneous co-delivery of hydrophobic drugs, relatively small size of LNC25-T/pDNA complexes, and fluorescence imaging can be crucial for gene therapy, as small particle sizes may be more favorable for in vivo studies.


Asunto(s)
Portadores de Fármacos/química , Lípidos/química , Nanocápsulas/química , Plásmidos/metabolismo , Polietileneimina/química , Antineoplásicos Fitogénicos/química , Antineoplásicos Fitogénicos/toxicidad , Apoptosis/efectos de los fármacos , Células HEK293 , Humanos , Microscopía Confocal , Paclitaxel/química , Paclitaxel/toxicidad , Tamaño de la Partícula , Transfección
18.
Nanoscale ; 5(21): 10562-72, 2013 Nov 07.
Artículo en Inglés | MEDLINE | ID: mdl-24056802

RESUMEN

Hypericin (Hy), a naturally occurring photosensitizer (PS), is extracted from Hypericum perforatum plants, commonly known as St. John's wort. The discovery of the in vitro and in vivo photodynamic activities of hypericin as a photosensitizer generated great interest, mainly to induce a very potent antitumoral effect. However, this compound belongs to the family of naphthodianthrones which are known to be poorly soluble in physiological solutions and produce non-fluorescent aggregates (A. Wirz et al., Pharmazie, 2002, 57, 543; A. Kubin et al., Pharmazie, 2008, 63, 263). These phenomena can reduce its efficiency as a photosensitizer for the clinical application. In the present contribution, we have prepared, characterized, and studied the photochemical properties of Hy-loaded lipid nanocapsule (LNC) formulations. The amount of singlet oxygen ((1)O2) generated was measured by the use of p-nitroso-dimethylaniline (RNO) as a selective scavenger under visible light irradiation. Our results showed that Hy-loaded LNCs suppressed aggregation of Hy in aqueous media, increased its apparent solubility, and enhanced the production of singlet oxygen in comparison with free drug. Indeed, encapsulation of Hy in LNCs led to an increase of (1)O2 quantum yield to 0.29-0.44, as compared to 0.02 reported for free Hy in water. Additionally, we studied the photodynamic activity of Hy-loaded LNCs on human cervical carcinoma (HeLa) and Human Embryonic Kidney (HEK) cells. The cell viability decreased radically to 10-20% at 1 µM, reflecting Hy-loaded LNC25 phototoxicity.


Asunto(s)
Lípidos/química , Nanocápsulas/química , Perileno/análogos & derivados , Fármacos Fotosensibilizantes/química , Fármacos Fotosensibilizantes/farmacología , Antracenos , Línea Celular , Supervivencia Celular/efectos de los fármacos , Portadores de Fármacos/síntesis química , Portadores de Fármacos/química , Células HeLa , Humanos , Hypericum/química , Hypericum/metabolismo , Luz , Microscopía por Video , Neoplasias/tratamiento farmacológico , Tamaño de la Partícula , Perileno/química , Perileno/farmacología , Perileno/uso terapéutico , Fotoquimioterapia , Fármacos Fotosensibilizantes/uso terapéutico , Oxígeno Singlete/metabolismo , Espectrofotometría Ultravioleta
19.
Food Chem ; 139(1-4): 796-803, 2013 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-23561175

RESUMEN

The seed composition of four varieties of Opuntia ficus-indica growing in Algeria was investigated. Seeds ground into a fine powder were first, subjected to oil extraction and fatty acids analysis. The phenolic compounds were then extracted from the defatted powder of seeds in order to be quantified and characterised by liquid chromatography coupled to mass spectrometry (LC-MS(n)) and to nuclear magnetic resonance (LC-NMR) approaches. In addition, an evaluation of the antioxidant activity of the phenolic extracts was investigated. Gas chromatography analysis of the seed oil showed high percentages of linoleic acid in the four varieties ranging from 58% to 63%. The phenolic profile of the Opuntia ficus-indica seeds displayed a high complexity, with more than 20 compounds detected at 330 nm after the LC separation. Among them, three isomers of feruloyl-sucrose were firmly identified and another was strongly supposed to be a sinapoyl-diglycoside. High correlations were found between phenolic content in the defatted seed extracts and their antioxidant activity. The data indicate that the defatted cactus seed wastes still contain various components that constitute a source for natural foods.


Asunto(s)
Opuntia/química , Fenoles/química , Extractos Vegetales/química , Aceites de Plantas/química , Semillas/química , Cromatografía de Gases , Ácidos Grasos/química , Espectrometría de Masas
20.
Nanoscale ; 5(7): 2692-702, 2013 Apr 07.
Artículo en Inglés | MEDLINE | ID: mdl-23420060

RESUMEN

The synthesis of multifunctional magnetic nanoparticles (MF-MPs) is one of the most active research areas in advanced materials as their multifunctional surfaces allow conjugation of biological and chemical molecules, thus making it possible to achieve target-specific diagnostic in parallel to therapeutics. We report here a simple strategy to integrate in a one-step reaction several reactive sites onto the particles. The preparation of MF-MPs is based on their simultaneous modification with differently functionalized dopamine derivatives using simple solution chemistry. The formed MF-MPs show comparable magnetic properties to those of naked nanoparticles with almost unaltered particle size of around 25 nm. The different termini, amine, azide and maleimide functions, enable further functionalization of MF-MPs by the grafting-on approach. Michael addition, Cu(i) catalyzed « click ¼ chemistry and amidation reactions are performed on the MF-MPs integrating subsequently 6-(ferrocenyl)-hexanethiol, horseradish peroxidase (HRP) and mannose.


Asunto(s)
Dopamina/química , Compuestos Férricos/química , Nanopartículas de Magnetita/química , Alquinos/síntesis química , Alquinos/química , Alquinos/farmacología , Azidas/síntesis química , Azidas/química , Azidas/farmacología , Catálisis , Enlace de Hidrógeno , Magnetismo/instrumentación , Magnetismo/métodos , Maleimidas/química , Maleimidas/farmacología , Tamaño de la Partícula , Propiedades de Superficie
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